Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 12/26/14
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
1134 PM CST TUE DEC 23 2014
.AVIATION...
CLOUDS WILL CONTINUE OVER THE AREA TONIGHT AND MUCH OF WEDNESDAY.
THE UPPER LEVEL LOW CONTINUES WEST OF ARKANSAS AND WILL SLOWLY MOVE
EAST. LIGHT RAIN WILL REDEVELOP OVERNIGHT AND CONTINUE SPORADICALLY
THROUGH THE FIRST HALF OF WEDNESDAY. CLOUDS WILL BREAK UP LATE IN
THE AFTERNOON AND EVENING. VFR CONDITIONS WILL BECOME MVFR TO LIFR.
&&
.PREV DISCUSSION... /ISSUED 814 PM CST TUE DEC 23 2014/
DISCUSSION...
MOISTURE CHANNEL IMAGERY REVEALS THE LOCATION OF THE MID LEVEL
TROUGH QUITE EASILY AS IT ROTATES THROUGH THE CENTRAL AND SOUTHERN
PLAINS. ANOTHER ROUND OF RAIN IS EXPECTED OVER MAINLY THE EASTERN
HALF OF THE STATE TONIGHT AS THE TROUGH LIFTS THROUGH. STILL
LOOKING AT A LITTLE MIX ON THE TAIL END OF THE SYSTEM AS IT PULLS
OUT BUT LITTLE IF ANY ACCUMULATION EXPECTED.
FORECAST IN GOOD SHAPE BUT WEATHER/POP GRIDS WERE REWORKED TO
REFLECT CURRENT TRENDS AND HRRR SOLUTION. ALL OTHER FORECAST
ELEMENTS LEFT AS IS AND ALL UPDATES ARE OUT.
PREV DISCUSSION... /ISSUED 556 PM CST TUE DEC 23 2014/
AVIATION...
AN UPPER TROUGH REMAINS JUST WEST OF ARKANSAS THIS EVENING. CLOUDS
WILL CONTINUE ACROSS THE AREA AND CEILINGS WILL LOWER OVERNIGHT.
RAIN CHANCES WILL ALSO INCREASE OVERNIGHT AND CONTINUE INTO
WEDNESDAY MORNING. CLOUDS COULD BREAK UP LATE IN THE PERIOD. LIFR
TO MVFR CONDITIONS ARE MAINLY EXPECTED.
PREV DISCUSSION... /ISSUED 255 PM CST TUE DEC 23 2014/
SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT
UPR LVL TROF RMND SITUATED TO THE W OF AR THIS AFTN. THIS RESULTING
SWLY FLOW ALOFT WAS BRINGING ANOTHER SHRTWV THRU THE FA WITH ASSOCD
RAINFALL NOW WORKING ACRS CNTRL AR. SUBSIDENCE BEHIND THE SHRTWV HAS
RESULTED IN SOME BINOVC OVR PARTS OF WRN AR AT MID AFTN.
MEANWHILE...CDFNT WAS LOCATED WELL E OF THE AREA WITH N/NWLY WINDS
ALLOWING COOLER AIR TO ADVECT INTO THE STATE.
THE AFOREMENTIONED SHRTWV WL CONT TO LIFT NEWD OUT OF THE AREA THIS
EVENING. ANTICIPATE A LULL IN THE PRECIP THIS EVENING AND PLAN TO
ADJUST EVENING POPS BASED ON RADAR TRENDS. BY LATER TNGT AND ON
WED...THE MAIN UPR TROF WL SHIFT EWD THRU THE MID SOUTH. ANOTHER
ROUND OF RAIN WL ACCOMPANY THIS SYS...WITH THE HIGHEST POPS
MENTIONED FOR THE ERN HALF OF THE FA.
RAIN CHCS WL DIMINISH FM THE SW ON WED AS THE UPR LVL SYS AND ASSOCD
SFC LOW LIFT NEWD AWAY FM THE FA. CURRENT FCST TRENDS STILL LOOK
GOOD INDCG SMALL POPS ACRS NRN AR WED AFTN. ONE CONCERN STILL
LINGERS REGARDING THE CHC OF SOME WET SNOW ACRS PARTS OF WRN AND NRN
AR LATE TNGT AND WED MRNG AS COLDER AIR ALOFT /ASSOCD WITH THE UPR
TROF/ MOVES OVR THE AREA. MODEL DATA CONT TO SHOW THAT SFC TEMPS WL
STAY ABV FRZG IN MOST LOCATIONS FOR MUCH IN THE WAY OF ANY SNOW
ACCUMULATION. HOWEVER...SOME OF THE HIGHER ELEVATIONS COULD SEE A
BURST OF WET SNOW BEFORE ENDING...WITH POSSIBLY SOME MINOR
ACCUMULATION ON GRASSY SURFACES.
THE STORM SYS WL CONT TO PULL AWAY FM THE REGION WED NGT AND THU...
WITH DRIER CONDS RETURNING. THIS WL BE SHORT LIVED THOUGH AS YET
ANOTHER FAST MOVG STORM SYS WL BRING RAIN CHCS BACK THE NATURAL
STATE FRI AND FRI NGT.
LONG TERM...SATURDAY THROUGH TUESDAY
ON SATURDAY A STORM SYSTEM AND COLD FRONT WILL BE MOVING THROUGH THE
REGION...AND FORECAST HAS A GOOD CHANCE OF RAIN. MAINLY A SHOWER
EVENT...WHILE THE GFS CONTINUES TO BE FASTER THEN THE EURO. HAVE
TRENDED TO THE SLOWER EURO AND KEEP MORE PRECIP OVER AR THROUGH
SUNDAY...THEN THE PRECIP GRADUALLY MOVING OUT OF AR LATER SUNDAY.
THE UPPER LOW PRESSURE TROUGH LAGS THE SURFACE SYSTEM AND HENCE
HOLDING OF THE PRECIP ON SUNDAY BEFORE MOVING EAST. IN THE OVERNIGHT
AND EARLY MORNING PERIODS...SOME LOW CHANCES OF A WINTRY MIX WILL BE
POSSIBLE...MAINLY OVER WEST CENTRAL...TO THE NORTHERN HALF OF
AR...AS TEMPS LOWER TO AROUND THE FREEZING MARK. LITTLE TO NO
SIGNIFICANT AMOUNTS ARE EXPECTED. DRY AND COOL MONDAY...BUT SOME
CLOUDS WILL STILL BE SEEN UNTIL THE UPPER TROUGH TOTALLY EXISTS
EAST. TUESDAY MAY SEE A REINFORCING SHOT OF COLD AIR BUT SOME
UNCERTAINTY DOES EXIST IN THE FORECAST THIS FAR OUT IN THE FORECAST.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 50 38 44 31 / 60 60 40 10
CAMDEN AR 52 38 47 31 / 60 50 20 0
HARRISON AR 52 34 39 28 / 20 30 40 10
HOT SPRINGS AR 49 37 45 30 / 60 40 20 0
LITTLE ROCK AR 51 39 46 31 / 60 50 20 0
MONTICELLO AR 56 41 47 33 / 60 60 20 0
MOUNT IDA AR 51 35 43 28 / 60 30 20 0
MOUNTAIN HOME AR 50 36 41 29 / 30 40 40 10
NEWPORT AR 49 39 45 31 / 60 60 40 10
PINE BLUFF AR 51 40 47 32 / 60 60 20 0
RUSSELLVILLE AR 51 37 44 28 / 50 40 20 0
SEARCY AR 50 39 45 29 / 60 60 30 10
STUTTGART AR 50 40 46 31 / 60 60 30 0
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AVIATION...65
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
512 AM PST WED DEC 24 2014
...LOCALLY BLUSTERY CONDITIONS NEAR THE COAST AND IN THE HILLS TONIGHT
THROUGH CHRISTMAS MORNING...
...MUCH COOLER WEATHER BY CHRISTMAS DAY...
.SYNOPSIS...A COLD FRONT WILL SWEEP ACROSS THE REGION TODAY
LEADING TO AREAS OF LIGHT RAIN. BRISK NORTHWEST WINDS WILL DEVELOP
BEHIND THE COLD FRONT BY LATE IN THE AFTERNOON. LOCALLY STRONG
AND GUSTY WINDS WILL OCCUR ALONG THE COAST AND IN THE HILLS
TONIGHT INTO CHRISTMAS MORNING. OTHERWISE CHRISTMAS DAY WILL BE DRY AND
COOL WITH DRY WEATHER EXPECTED TO CONTINUE THROUGH NEXT WEEK.
FREEZING OVERNIGHT LOW TEMPERATURES ARE LIKELY FOR SOME INLAND
VALLEYS LATE IN THE WEEK AND INTO THE WEEKEND.
&&
.DISCUSSION...AS OF 3:00 AM PST WEDNESDAY...SIMILAR TO THE PAST
FEW MORNINGS PATCHY FOG HAS DEVELOPED ACROSS PORTIONS OF OUR
CWA...IN PARTICULAR OVER THE NORTH BAY PLUS AROUND SF BAY. SOME
REPORTS OF VERY LOW VISIBILITIES IN A FEW SPOTS. IN FACT OAKLAND
HAS DROPPED DOWN TO AN EIGHT OF A MILE AND A SPOTTER IN THE
BERKELEY AREA REPORTED VERY LOW VALUES AS WELL. OUTSIDE OF THE FOG
ALSO WORTH NOTING THAT TEMPS ARE RUNNING 2 TO 5 DEGREES COOLER
THAN YESTERDAY IN MOST SPOTS ALONG WITH DEW POINTS RUNNING ABOUT
THE SAME AMOUNT LOWER.
ONCE THE FOG BURNS OFF THE MAIN STORY FOR TODAY WILL BE A COLD
FRONT THAT WILL SWEEP THROUGH OUR AREA AND PROVIDE ANOTHER ROUND
OF RAIN ESPECIALLY FOR THE NORTHERN THIRD OF THE CWA. LATEST
GUIDANCE IN IS IN FAIRLY GOOD AGREEMENT THAT RAIN WILLS START OVER
THE NORTH BAY LATE IN THE MORNING TO EARLY AFTERNOON AND PROGRESS
DOWN TO THE SF BAY REGION OVER THE AFTERNOON AND THEN DISSIPATE BY
THE EVENING AS IT ENTERS THE MONTEREY BAY REGION. RAINFALL AMOUNTS
WILL BE VERY LIGHT COMPARED TO RECENT STORMS HOWEVER LOCALLY MORE
THAN A QUARTER OF AN INCH IS POSSIBLE ESPECIALLY ALONG THE COAST
FROM SAN MATEO COUNTY TO THE NORTH. URBAN LOCATIONS WILL LIKELY BE
CLOSER TO A TENTH OF AN INCH. WORTH NOTING THAT THE NEWEST RUN OF
THE HRRR JUST IN HAS BACKED OFF A BIT WITH THE QPF.
WHAT WILL LIKELY BE A BIGGER STORY OUT OF THE SYSTEM GOING THROUGH
TODAY WILL BE WIND AND COOLER TEMPERATURES. WINDS WILL PICK UP AS
THE FRONT GOES THROUGH AND COLDER AIR MOVES INTO THE AREA. 850 MB
SPEEDS PICK UP TO THE 35 TO 50 KT RANGE WITH MODEL SOUNDINGS
KEEPING THE STRONGER SPEEDS GENERALLY ABOVE THE 1000 FT LEVEL
SUGGESTING THAT THE BIGGEST IMPACTS WILL BE OVER THE HILLS. DUE TO
RECENT RAIN WOULD EXPECT TO GET REPORTS OF TREES BEING TOPPLED
ESPECIALLY FOR ANY SPOTS ALONG RIDGES THAT HAVE A NW EXPOSURE.
LOCAL GUSTS TO 40 MPH CAN BE EXPECTED ABOVE 2000 FEET.
TEMPERATURES WILL DECREASE BOTH DURING THE DAY AND AT NIGHT OVER
THE NEXT COUPLE OF DAYS AND MUCH COOLER AND DRIER AIR SETTLES
ACROSS THE CWA. BIGGEST CONCERN WILL BE THE OVERNIGHT LOWS
ESPECIALLY BY THURSDAY AND FRIDAY NIGHT. BOTH OF THESE WILL LIKELY
HAVE SOME OF OUR COOLEST READINGS IN QUITE SOME TIME WITH INTERIOR
SPOTS FORECAST TO DROP INTO THE 30S WITH EVEN SOME UPPER 20S NOT
OUT OF THE QUESTION. COASTAL SPOTS WILL STAY A BIT MILDER THANKS
IN LARGE PART TO SEA SURFACE TEMPERATURES STILL RUNNING WELL ABOVE
NORMAL.
THE COOLER AND DRY WEATHER WILL CONTINUE INTO NEXT WEEK AS THE
OVERALL FLOW REMAINS FROM THE NW. OUTSIDE OF THE CHANCE OF RAIN
TODAY NO SIGN OF PRECIPITATION OUT THROUGH NEXT FRIDAY.
&&
.AVIATION...AS OF 5:00 AM PST WEDNESDAY...LOW CIGS WITH PATCHY
DENSE FOG IS PRESENT AGAIN THIS MORNING AROUND THE SFO BAY AREA.
OAK VSBY HAS BEEN 1/8 TO 1/4 MILE OVERNIGHT. SO THE POSSIBILITY
EXISTS THAT SFO VSBYS MAY DROP TO 1/4 TO 1/2 MILE BETWEEN 14Z AND
18Z. COMPLICATING THINGS IS THE APPROACHING FRONTAL SYSTEM WHICH
MAY PROVIDE ENOUGH MIXING TO KEEP FOG OUT OF SFO. WINDS WILL BE
LIGHT THIS MORNING BUT WILL BECOME A FACTOR WHEN THE FRONT
ARRIVES IN THE SFO BAY AREA AFTER 22Z. NORTHWEST WINDS EXPECTED TO
INCREASE TO 15-20 KT WITH GUSTS 25-30 KT.
VICINITY OF KSFO...IFR CIGS WITH VSBYS POSSIBLY LOWERING TO 1/4 TO
1/2 BETWEEN 14Z AND 18Z. BY 19Z CIGS WILL LIFT TO MVFR RANGE BUT
APPROACHING FRONT LIKELY TO KEEP THESE CIGS IN THROUGH THE REST OF
THE DAY. A BRIEF PERIOD OF LIGHT RAIN IS EXPECTED 22Z-02Z WITH
RAPID CLEARING AFTER THAT AS THIS IS A QUICK MOVING SYSTEM. WINDS
INCREASING TO NORTHWEST 15-20 KT WITH GUSTS 25-30 KT AFTER 22Z.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...PATCHY IFR CIGS AROUND MRY THROUGH
15-16Z. MVFR CIGS AFTER 23Z WITH OCCASIONAL LIGHT RAIN THROUGH 03Z.
SOUTHEAST WINDS TO 10 KT THIS MORNING WITH STRONGEST WINDS THROUGH
THE SALINAS VALLEY. WINDS SWITCHING TO NORTHWEST 10-15 KT WITH
GUSTS AS HIGH AS 20 KT AFTER 21Z.
&&
.MARINE...AS OF 3:00 AM PST WEDNESDAY...A FAST MOVING TROUGH AND COLD
FRONT WILL MOVE SOUTHEAST OVER THE AREA THIS AFTERNOON AND
EVENING. STRONG NORTHWEST WINDS WILL DEVELOP OVER THE COASTAL
WATERS TONIGHT AND THURSDAY AFTER THE FRONT PASSES WITH GALE FORCE
WINDS OVER THE OUTER WATERS.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...GLW...PT ARENA TO PT REYES 10-60 NM FROM 1 PM
GLW...PT REYES TO PIGEON PT 10-60 NM FROM 1 PM
GLW...PIGEON PT TO PT PINOS 10-60 NM FROM 4 PM
SCA...PT ARENA TO PT REYES 0-10 NM FROM 1 PM
SCA...PT REYES TO PIGEON PT 0-10 NM FROM 4 PM
SCA...ROUGH BAR ADVISORY FOR SF BAR FROM 4 PM
&&
$$
PUBLIC FORECAST: BELL
AVIATION/MARINE: W PI
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
307 AM PST WED DEC 24 2014
...LOCALLY BLUSTERY CONDITIONS NEAR THE COAST AND IN THE HILLS TONIGHT
THROUGH CHRISTMAS MORNING...
...MUCH COOLER WEATHER BY CHRISTMAS DAY...
.SYNOPSIS...A COLD FRONT WILL SWEEP ACROSS THE REGION TODAY
LEADING TO AREAS OF LIGHT RAIN. BRISK NORTHWEST WINDS WILL DEVELOP
BEHIND THE COLD FRONT BY LATE IN THE AFTERNOON. LOCALLY STRONG
AND GUSTY WINDS WILL OCCUR ALONG THE COAST AND IN THE HILLS
TONIGHT INTO CHRISTMAS MORNING. OTHERWISE CHRISTMAS DAY WILL BE DRY AND
COOL WITH DRY WEATHER EXPECTED TO CONTINUE THROUGH NEXT WEEK.
FREEZING OVERNIGHT LOW TEMPERATURES ARE LIKELY FOR SOME INLAND
VALLEYS LATE IN THE WEEK AND INTO THE WEEKEND.
&&
.DISCUSSION...AS OF 3:00 AM PST WEDNESDAY...SIMILAR TO THE PAST
FEW MORNINGS PATCHY FOG HAS DEVELOPED ACROSS PORTIONS OF OUR
CWA...IN PARTICULAR OVER THE NORTH BAY PLUS AROUND SF BAY. SOME
REPORTS OF VERY LOW VISIBILITIES IN A FEW SPOTS. IN FACT OAKLAND
HAS DROPPED DOWN TO AN EIGHT OF A MILE AND A SPOTTER IN THE
BERKELEY AREA REPORTED VERY LOW VALUES AS WELL. OUTSIDE OF THE FOG
ALSO WORTH NOTING THAT TEMPS ARE RUNNING 2 TO 5 DEGREES COOLER
THAN YESTERDAY IN MOST SPOTS ALONG WITH DEW POINTS RUNNING ABOUT
THE SAME AMOUNT LOWER.
ONCE THE FOG BURNS OFF THE MAIN STORY FOR TODAY WILL BE A COLD
FRONT THAT WILL SWEEP THROUGH OUR AREA AND PROVIDE ANOTHER ROUND
OF RAIN ESPECIALLY FOR THE NORTHERN THIRD OF THE CWA. LATEST
GUIDANCE IN IS IN FAIRLY GOOD AGREEMENT THAT RAIN WILLS START OVER
THE NORTH BAY LATE IN THE MORNING TO EARLY AFTERNOON AND PROGRESS
DOWN TO THE SF BAY REGION OVER THE AFTERNOON AND THEN DISSIPATE BY
THE EVENING AS IT ENTERS THE MONTEREY BAY REGION. RAINFALL AMOUNTS
WILL BE VERY LIGHT COMPARED TO RECENT STORMS HOWEVER LOCALLY MORE
THAN A QUARTER OF AN INCH IS POSSIBLE ESPECIALLY ALONG THE COAST
FROM SAN MATEO COUNTY TO THE NORTH. URBAN LOCATIONS WILL LIKELY BE
CLOSER TO A TENTH OF AN INCH. WORTH NOTING THAT THE NEWEST RUN OF
THE HRRR JUST IN HAS BACKED OFF A BIT WITH THE QPF.
WHAT WILL LIKELY BE A BIGGER STORY OUT OF THE SYSTEM GOING THROUGH
TODAY WILL BE WIND AND COOLER TEMPERATURES. WINDS WILL PICK UP AS
THE FRONT GOES THROUGH AND COLDER AIR MOVES INTO THE AREA. 850 MB
SPEEDS PICK UP TO THE 35 TO 50 KT RANGE WITH MODEL SOUNDINGS
KEEPING THE STRONGER SPEEDS GENERALLY ABOVE THE 1000 FT LEVEL
SUGGESTING THAT THE BIGGEST IMPACTS WILL BE OVER THE HILLS. DUE TO
RECENT RAIN WOULD EXPECT TO GET REPORTS OF TREES BEING TOPPLED
ESPECIALLY FOR ANY SPOTS ALONG RIDGES THAT HAVE A NW EXPOSURE.
LOCAL GUSTS TO 40 MPH CAN BE EXPECTED ABOVE 2000 FEET.
TEMPERATURES WILL DECREASE BOTH DURING THE DAY AND AT NIGHT OVER
THE NEXT COUPLE OF DAYS AND MUCH COOLER AND DRIER AIR SETTLES
ACROSS THE CWA. BIGGEST CONCERN WILL BE THE OVERNIGHT LOWS
ESPECIALLY BY THURSDAY AND FRIDAY NIGHT. BOTH OF THESE WILL LIKELY
HAVE SOME OF OUR COOLEST READINGS IN QUITE SOME TIME WITH INTERIOR
SPOTS FORECAST TO DROP INTO THE 30S WITH EVEN SOME UPPER 20S NOT
OUT OF THE QUESTION. COASTAL SPOTS WILL STAY A BIT MILDER THANKS
IN LARGE PART TO SEA SURFACE TEMPERATURES STILL RUNNING WELL ABOVE
NORMAL.
THE COOLER AND DRY WEATHER WILL CONTINUE INTO NEXT WEEK AS THE
OVERALL FLOW REMAINS FROM THE NW. OUTSIDE OF THE CHANCE OF RAIN
TODAY NO SIGN OF PRECIPITATION OUT THROUGH NEXT FRIDAY.
&&
.AVIATION...AS OF 9:17 PM PST TUESDAY...LIGHT WINDS...CLEAR SKIES
AND RADIATIONAL COOLING TONIGHT WILL ALLOW AIR TEMPERATURES TO
COOL CLOSE TO THE DEWPOINT TEMPERATURES ONCE AGAIN. THEREFORE FOG
PATCHES MAY BE A LITTLE MORE EXTENSIVE IN COVERAGE BY EARLY
WEDNESDAY. IT`S A MODERATE TO HIGH CONFIDENCE VFR FORECAST FOR
THE EVENING BUT CONFIDENCE IN THE FORECASTS LOWERS LATE AT NIGHT
DUE TO POSSIBLE FOG DEVELOPMENT.
ON WEDNESDAY A FAST MOVING TROUGH ACCOMPANIED BY A COLD FRONTAL
PASSAGE WILL RESULT IN ENOUGH LIGHT RAIN TO PRODUCE WET RUNWAYS
AND THE POTENTIAL FOR AREAS OF GUSTY W-NW WINDS BY LATE MORNING
AND EARLY AFTERNOON. A BRIEF INCREASE IN THE WINDS IS ALSO
POSSIBLE WEDNESDAY OVER THE NORTH CENTRAL COAST.
VICINITY OF KSFO...VFR IS FORECAST THROUGH THE EVENING. SOME FOG
PATCHES ARE POSSIBLE BY EARLY WEDNESDAY. EARLIER COORDINATION WITH
CWSU OFFICE LED TO DECISION TO GO FORECAST TEMPO IFR CIGS 13Z-17Z
WITH CEILINGS RAPIDLY LIFTING TO MVFR BY MID-LATE MORNING. WEATHER
CHANGES ARE GOING TO BE RAPID WEDNESDAY AS THIS IS A QUICKLY MOVING
WEATHER SYSTEM.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...LOW TO MODERATE CONFIDENCE VFR HOLDS
FOR THE EVENING. LOCAL IFR INCREASINGLY LIKELY AFTER MIDNIGHT AS THE
SURFACE TEMPS COOL OFF AND LIGHT WINDS ALLOW FOR A FEW FOG PATCHES OR
LOW CEILINGS. CLOUDS INCREASE BY AFTERNOON WITH LIGHT RAIN ARRIVING
CLOSE TO 00Z.
&&
.MARINE...AS OF 3:00 AM PST WEDNESDAY...A FAST MOVING TROUGH AND COLD
FRONT WILL MOVE SOUTHEAST OVER THE AREA THIS AFTERNOON AND
EVENING. STRONG NORTHWEST WINDS WILL DEVELOP OVER THE COASTAL
WATERS TONIGHT AND THURSDAY AFTER THE FRONT PASSES WITH GALE FORCE
WINDS OVER THE OUTER WATERS.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...GLW...PT ARENA TO PT REYES 10-60 NM FROM 1 PM
GLW...PT REYES TO PIGEON PT 10-60 NM FROM 1 PM
GLW...PIGEON PT TO PT PINOS 10-60 NM FROM 4 PM
SCA...PT ARENA TO PT REYES 0-10 NM FROM 1 PM
SCA...PT REYES TO PIGEON PT 0-10 NM FROM 4 PM
SCA...ROUGH BAR ADVISORY FOR SF BAR FROM 4 PM
&&
$$
PUBLIC FORECAST: BELL
AVIATION: CANEPA
MARINE: W PI
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AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
832 PM MST THU DEC 25 2014
.UPDATE...
ISSUED AT 832 PM MST THU DEC 25 2014
WEATHER SCENARIO EVOLVING MUCH AS EXPECTED AS THE CENTER OF THE
UPPER LOW PROGRESSES TOWARD THE FOUR-CORNERS AND EASTERN COLORADO
LIES UNDER THE DIFFLUENT REGION DOWNSTREAM FROM THE UPPER TROUGH.
AT THE SURFACE...MODEST UPSLOPE FLOW CONTINUES AS THE MAIN SURFACE
LOW HOLDS ITS POSITION OVER THE SOUTHEAST CORNER OF THE STATE.
SNOW ACCUMULATIONS OF 2 TO 5 INCHES HAVE BEEN REPORTED UP AND DOWN
THE FRONT RANGE SO FAR THIS EVENING. FARTHER TO THE
NORTHEAST...WINDS ARE A BIT STRONGER...CAUSING SOME BLOWING AND
DRIFTING SNOW IN LOGAN...SEDGWICK AND PHILLIPS COUNTIES.
MODEL SOUNDINGS FROM THIS EVENINGS NAM RUN SHOW THAT A MID-LEVEL
INVERSION WILL BE DEVELOPING BY 06Z WHICH SHOULD CHANGE THE
CHARACTERISTICS OF THE SNOWFALL FOR THE LATTER HALF OF TONIGHT.
QPF FORECASTS FROM THE RAP AND HRRR MODELS ALSO SHOW THAT
INTENSITY WILL BE FALLING OFF IN THE NEXT FEW HOURS. THE CURRENT
SET OF HIGHLIGHTS AND SNOWFALL FORECASTS LOOK LIKE THEY WILL
HANDLE THE SITUATION WELL ENOUGH...SO NO CHANGES ARE FORTHCOMING.
THE EVENING RUN OF THE NAM NOW SHOWS THAT THE UPPER LOW IS NOT
GOING TO CLEAR OUT OF THE STATE UNTIL FRIDAY EVENING. WILL
INCREASE THE POPS THROUGH FRIDAY AFTERNOON. EXPECTED SNOW
ACCUMULATIONS THROUGH THE DAYLIGHT HOURS ON FRIDAY SHOULD BE LESS
THAN AN INCH OR TWO...GIVEN THAT MODEL SOUNDINGS ARE SHOWING THE
MID-LEVEL INVERSION WITH SOME DRYING ALOFT CONTINUING THROUGH THE
DAY.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 314 PM MST THU DEC 25 2014
THE MAIN STORM SYSTEM CONTINUES TO DIG SOUTHEAST INTO UTAH THIS
AFTERNOON. NORTHEASTERLY UPSLOPE FLOW HAS SPREAD ACROSS THE
PLAINS BEHIND THIS MORNINGS COLD FRONT...WITH LIGHT SNOW BEGINNING
TO PUSH SOUTH. THE HEAVIER SNOW OCCURRING ALONG THE WYOMING
BORDER TODAY IS EXPECTED TO BEGIN TO PUSH SOUTH AS ANOTHER SURGE
PUSHES INTO THE STATE. THE AREAS ARE MOSTLY COVERED UNDER
ADVISORIES AND WARNINGS...EXCEPT LOGAN...MORGAN...PHILLIPS AND
SEDGWICK COUNTIES WHERE 3-5 INCHES ARE EXPECTED TO FALL OVERALL.
CURRENT RADAR AND HI-RES MODEL TRENDS ARE HITTING WELD COUNTY
MORE...MAY NEED TO UPGRADE EASTERN WELD TO A WARNING. HOWEVER WITH
THE MORE NORTHERLY PUSH EXPECTED THIS EVENING...MORE THAN LIKELY
THE NORTHERN FRONT RANGE URBAN CORRIDOR AND PLAINS WILL HAVE SNOW
GREATLY DECREASE AS DOWNSLOPING OCCURS OFF THE CHEYENNE RIDGE.
MAIN PUSH STILL EXPECTED TO OCCUR BETWEEN 5PM AND MIDNIGHT WITH
HEAVIER SNOWFALL RATES ALONG AND EAST OF THE DIVIDE AND FRONT
RANGE MOUNTAINS. QG VERTICAL VELOCITIES ARE WEAK UPWARD WHICH IS
NOT FAVORED FOR HIGH SNOW AMOUNTS...BUT GOOD ENOUGH UPSLOPE FLOW
WITH THE AVAILABLE MOISTURE AND COLD ADVECTION SHOULD HELP IT OUT.
WEST OF THE DIVIDE...SNOW HAS TAKEN A WHILE TO GET GOING IN THE
UNFAVORED SOUTH TO SOUTHWESTERLY FLOW. THIS EVENING...OROGRAPHICS
ARE NOT THE BEST BUT UPWARD QG VERTICAL VELOCITIES INCREASE...WILL
ALLOW THE ADVISORIES TO CARRY ON.
THE UPPER LOW WILL MOVE OVER THE FOUR CORNERS EARLY TOMORROW
MORNING THEN WEAKEN AND BECOME AN OPEN TROUGH FRIDAY AFTERNOON.
AS THIS HAPPENS...QG VERTICAL VELOCITIES WILL INCREASE UPWARD.
HIGH SURFACE PRESSURE OVER THE GREAT NORTHERN PLAINS WILL KEEP
NORTH TO NORTHEASTERLY UPSLOPE FLOW OVER THE FRONT RANGE
MOUNTAINS...FOOTHILLS AND PLAINS. OVERALL THE SPEED OF THE LOW HAS
SLOWED DOWN OVER PAST RUNS WHICH WILL PROVIDE A MORE FAVORABLE
ENVIRONMENT FOR SNOW TO CONTINUE THROUGH TOMORROW. HAVE INCREASED
CHANCES OF PRECIPITATION AND PRECIP AMOUNTS AS WELL. SNOW AMOUNTS
OVER THE MOUNTAINS WILL BE LIGHT. BY AFTERNOON...UPSLOPE
FLOW DECREASES WHICH WILL START CLEARING IN AND NEAR THE
FOOTHILLS THEN SPREAD EAST.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 314 PM MST THU DEC 25 2014
GFS AND A MAJORITY OF ITS ENSEMBLE MEMBERS...NAM AND ECMWF ALL SHOW
THE 500 MB LOW TRACKING NORTHEASTWARD OVER NORTHEAST COLORADO BY
00Z/SAT. THE CANADIAN GEM HOWEVER STILL HAS THE UPPER LOW OVER S-
CNTRL COLORADO AT THAT TIME. OVERALL MODELS INDICATE GRADUAL
WEAKENING OF THE UPPER LOW AND RISING HEIGHTS AS THE TROUGH LIFTS
OVER WRN NEBRASKA FRIDAY EVENING. IN ADDITION 10-20KT N-NELY 850-
700MB FLOW OVER NERN COLORADO GRADUALLY BECOMES NWLY OVERNIGHT WITH
QG VV FIELDS INDICATING INCREASING DOWNWARD MOTION OVER THE CWA
AFTER MIDNIGHT. MOISTURE ALSO THINS OUT OVERNIGHT ACCORDING TO MODEL
CROSS SECTIONS WITH THE SHIFT TO A FLOW OFF THE CHEYENNE RIDGE.
HOWEVER RH FIELDS AND CROSS SECTIONS INDICATE SLOW CLEARING
CONSEQUENTLY PREVENTING TEMPERATURES FROM CRASHING WITH COLD POOL
ALOFT PASSING BY. ANY ADDITIONAL SNOW ACCUMULATION WILL BE MINIMAL
AND LARGELY CONFINED TO HIGHER ELEVATIONS OF THE FRONT RANGE AND OUT
NEAR THE NERN CORNER OF THE STATE. REDUCED POPS FRIDAY EVENING LOOK
GOOD BUT NOT AS LOW AS EARLIER THOUGHT.
FOR SATURDAY...WEAK MID-LEVEL INSTABILITY AND MOISTURE SWING DOWN
FROM WRN WYOMING SATURDAY MORNING WHICH COULD GENERATE A FEW LIGHT
SNOW SHOWERS OVER HIGHER ELEVATIONS. OTHERWISE DRYING WILL BE
UNDERWAY WITH DAYTIME TEMPERATURES WARMING SEVERAL DEGREES ABOVE
THOSE ON FRIDAY. DURING THE LATE AFTERNOON AND EVENING HOURS MTN TOP
STABLE LAYER INTENSIFIES WITH WARMING ALOFT. MODELS CROSS SECTIONS
SHOW WELL DEVELOP MTN WAVE FORMING OVER AND ALONG THE FRONT RANGE
WITH A 45-50KT CROSS BARRIER WIND COMPONENT AFTER 06Z/SUNDAY. CROSS
SECTIONS SHOW THIS MOMENTUM MOVING DOWN THE EAST FACE OF THE FRONT
RANGE POSSIBLY RESULTING IN 30-40KT WIND GUSTS IN THE LOWER
FOOTHILLS TOWARDS MORNING. THIS WILL BE A WARMING WIND SO LATE NIGHT
AND MORNING TEMPERATURES ALONG THE BASE OF THE FOOTHILLS WILL BE
QUITE MILD FOR THIS TIME OF YEAR.
ON SUNDAY...ATTENTION SHIFTS TO THE EXTENSIVE ARCTIC AIRMASS POOLING
TO THE WEST THROUGH NORTH OF COLORADO. ALSO WATCHING A PROGRESSIVE
UPPER TROUGH ON THE NOSE OF A POWERFUL PACIFIC JET DIVING OUT OF THE
PACIFIC NORTHWEST. MODELS SHOW THIS TROUGH AND THIS ARCTIC AIRMASS
SETTLING IN OVER THE CENTRAL ROCKY MTN REGION LATE SUNDAY INTO
MONDAY SETTING THE STAGE FOR WHAT PROMISES TO BE A VERY COLD AND
POSSIBLY SNOWY COUPLE OF DAYS EARLY NEXT WEEK. TEMPERATURES BY
MONDAY NIGHT AND TUESDAY COULD BE AS MUCH AS 35-40 DEGS F BELOW
AVERAGE...ESPLY EAST OF THE MTNS. SNOW CHANGES ALSO LIKELY TO GO UP
WITH A WEST-EAST ELONGATED UPPER TROUGH ANCHORING OVER THE GREAT
BASIN AND CENTRAL ROCKY MTN REGION. WITH THE AIRMASS AS COLD AS IT
MAY BE...SNOWFALL FOR THE MOST PART SHOULD BE A LIGHT FLUFFY SORT
OF SNOW.
DRIER AND WARMER CONDITIONS POSSIBLY RETURN FOR MIDWEEK WITH THE
UPPER TROUGH NOSING SWWRD OVER SRN CALIFORNIA.&&
.AVIATION...(FOR THE TAFS THROUGH 00Z FRIDAY LATE AFTERNOON)
ISSUED AT 314 PM MST THU DEC 25 2014
LIGHT SNOW OVER THE AREA AIRPORTS WITH MVFR CONDITIONS...EXPECTED
TO GET DOWN INTO THE IFR CATEGORY SOON. BEST CHANCE FOR HEAVIER
SNOW WILL HOLD OFF UNTIL AFTER 00Z WITH A SECONDARY COLD PUSH.
THEN EXPECT AN INCREASE IN COVERAGE AND INTENSITY THRU THE EARLY
EVENING HOURS. SNOW INTENSITY WILL DECREASE BY MIDNIGHT...BUT WILL
CONTINUE TO SEE LIGHT SNOW...WITH PERIODS OF MODERATE...THROUGH
FRIDAY EVENING. CEILINGS/VIS WILL LIKELY STAY IFR THROUGH THEN AS
WELL. RIGHT NOW WILL GO WITH ACCUMULATIONS IN THE 4 TO 6 INCH
RANGE FOR DIA...6 TO 9 INCH RANGE FOR KBJC AND KAPA THROUGH 00Z
FRIDAY EVENING.
NORTHERLY WINDS EXPECTED TO CONTINUE THROUGH THE EVENING WITH
DECREASING SPEEDS AFTER 06Z. NORTHERLY WINDS OVERNIGHT WILL TREND
NORTHEAST FRIDAY AFTERNOON.
&&
.AVIATION...(FOR THE TAFS THROUGH 06Z FRIDAY EVENING)
ISSUED AT 832 PM MST THU DEC 25 2014
IFR CONDITIONS ARE EXPECTED THROUGH MUCH OF THE NEXT 24 HOURS AS
THE WINTER STORM SLOWLY CROSSES OVER THE STATE. MOST OF THE SNOW
ACCUMULATIONS SHOULD BE IN THE NEXT FEW HOURS...WITH UP TO 3 MORE
INCHES...THEN ONLY AN INCH OR TWO FROM MIDNIGHT THROUGH FRIDAY
AFTERNOON. WINDS WILL BE NORTHERLY...BUT WITHOUT ANY STRONG
GUSTS...SO BLOWING SNOW IS NOT ANTICIPATED.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL NOON MST FRIDAY FOR COZ035-036-039-
041.
WINTER WEATHER ADVISORY UNTIL NOON MST FRIDAY FOR COZ031-033-034-
040-045-046.
WINTER STORM WARNING UNTIL 8 AM MST FRIDAY FOR COZ038.
WINTER WEATHER ADVISORY UNTIL 8 AM MST FRIDAY FOR COZ042-043.
&&
$$
UPDATE...DANKERS
SHORT TERM...KRIEDERMAN
LONG TERM...BAKER
AVIATION...DANKERS
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
1017 AM EST WED DEC 24 2014
.DISCUSSION...
COLD FRONT AND PRECEDING SQUALL LINE WILL CONTINUE EASTWARD
THROUGH THE EASTERN GULF INTO LATE MORN AND AFT. PROJECTED MOTION
HAS THIS BAND REACHING LAKE/INLAND VOLUSIA COUNTIES TOWARD SUNSET
IF NOT A LITTLE AFTER INTO THE EARLY EVE. THIS TIMING MATCHES WELL
WITH LATEST HRRR AND LOCAL WRF MODEL TRENDS. WILL MAINTAIN POPS UP
TO 60-70% OVER THIS REGION FOR THE EXPECTED LATE DAY INCREASE IN
SHOWER/STORM COVERAGE. ELSEWHERE WILL KEEP CHANCE POPS IN THE
FORECAST AS IT IS NOT OUT OF THE QUESTION TO SEE SHOWERS OR A FEW
STORMS DEVELOP OUT AHEAD OF THIS MAIN LINE INTO THE AFTERNOON.
SUFFICIENT HEATING...DEWPOINTS IN THE UPPER 60S/LOW 70S AND STRONG
LOW/MID LEVEL WINDS WILL SUPPORT SOME STRONGER STORMS AS THIS
SQUALL LINE INITIALLY MOVES INTO THE REGION WITH THE MAIN THREAT
BEING STRONG TO ISOLATED SEVERE WIND GUSTS. CONVECTIVE BAND WILL
THEN WEAKEN AS IT GRADUALLY PUSHES SOUTHEAST ACROSS THE REGION
TONIGHT.
LOWER CLOUDS OVER NORTHERN AREAS WILL BREAK UP INTO LATE MORNING
WITH PARTLY CLOUDY SKIES EXPECTED FOR MUCH OF THE AFTERNOON.
BREEZY CONDS EXPECTED TODAY WITH HIGHS FORECAST TO REACH THE LOW
TO MID 80S.
&&
.AVIATION...LOW CLOUDS PRODUCING MVFR CIGS WILL BREAK UP INTO THE
LATE MORNING WITH VFR CONDS GENERALLY EXPECTED INTO MUCH OF THE
AFTERNOON. BREEZY SOUTHERLY WINDS EXPECTED TODAY WITH SUSTAINED
WINDS 15-18 KTS AND GUSTS 20-25 KTS.
APPROACHING SQUALL LINE OVER THE EASTERN GULF NOT EXPECTED TO
REACH LAKE COUNTY UNTIL AFT 21-22Z. TEMPO IFR/MVFR CONDS WILL
OCCUR WITH THIS BAND OF SHOWERS/STORMS AS IT SHIFTS SOUTHEAST AND
WEAKENS INTO TONIGHT. HOWEVER AS BAND INITIALLY PUSHES INTO AREAS
ALONG AND WEST OF I-4 STRONG WIND GUSTS WILL BE POSSIBLE WITH ANY
STORMS.
&&
.MARINE...
TODAY-TONIGHT...POOR TO HAZARDOUS BOATING CONDITIONS WILL CONTINUE
OVER THE COASTAL WATERS OUT AHEAD OF AN APPROACHING COLD FRONT AND
PRECEDING BAND OF CONVECTION. SOUTHERLY WINDS UP TO 15-20 KNOTS
NEARSHORE AND AROUND 20 KNOTS OFFSHORE WITH SEAS UP TO 5 TO 6
FEET. THE SMALL CRAFT ADVISORY FOR WINDS WILL CONTINUE INTO THIS
EVENING WITH SMALL CRAFT EXERCISE CAUTION HEADLINES STILL NEEDED
NEARSHORE.
BAND OF CONVECTION WILL MOVE INTO THE COASTAL WATERS THIS EVENING
AND OVERNIGHT AND MAY BE ABLE TO PRODUCE STRONG GUSTY WINDS AS
THEY MOVE OFFSHORE. SOUTH TO SOUTHWEST WINDS BECOME NORTHWEST
TOWARD SUNRISE AS THE FRONTAL LINE MOVES DOWN THE PENINSULA.
BORDERLINE SCA/SCEC CONDITIONS EXPECTED OVERNIGHT OFFSHORE.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 PM EST THIS EVENING FOR
WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE 20
TO 60 NM OFFSHORE-WATERS FROM SEBASTIAN INLET TO JUPITER
INLET 20 TO 60 NM OFFSHORE-WATERS FROM VOLUSIA BREVARD
COUNTY LINE TO SEBASTIAN INLET 20 TO 60 NM OFFSHORE.
&&
$$
WEITLICH/CRISTALDI
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
141 AM EST WED DEC 24 2014
.PREV DISCUSSION... /ISSUED 748 PM EST TUE DEC 23 2014/
UPDATE...
LINE OF STRONG TO SEVERE THUNDERSTORMS ACROSS CENTRAL AL CONTINUES
EASTWARD THIS EVENING. THE LINE IS HOLDING STEADY AND IS EXPECTED
TO REACH THE AL/GA STATE LINE AROUND 10 PM. THE HRRR BEGINS TO
WEAKEN THE LINE RIGHT ALONG THE INTERSTATE 85 CORRIDOR RIGHT
AROUND OR JUST AFTER MIDNIGHT. GRADUAL WEAKENING OF THE LINE WOULD
OCCUR IF THE WEDGE CONTINUED TO HOLD STRONG EAST OF 85.
HOWEVER...STORMS SHOULD BECOME ELEVATED ACROSS THE EASTERN
PORTIONS OF THE CWFA. DO THINK SOME CONTINUED EROSION ON THE WEST
SIDE OF THE WEDGE IS LIKELY...BUT NOT CONFIDENCE ON EXACTLY HOW
MUCH.
HAVE MADE SOME TIMING TWEAKS FOR TSRA WITHIN THE GRIDS. IN
ADDITION...TWEAKED THE HOURLY TEMP/DEW GRIDS ACCORDING TO THE
POSITION OF THE WARM FRONT.
PREV DISCUSSION... /ISSUED 622 PM EST TUE DEC 23 2014/
PREV DISCUSSION... /ISSUED 244 PM EST TUE DEC 23 2014/
SEVERE STORMS REMAIN POSSIBLE TONIGHT AND WEDNESDAY...
HEAVY RAINFALL AND MINOR FLOODING LIKELY TONIGHT AND
WEDNESDAY...
SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
OVERALL FCST IN GOOD SHAPE. WARM FRONT STILL VERY SLOW TO MOVE
NORTH BUT SHOULD MARCH SLOWLY NORTH TONIGHT.
MONITORING SEVERE STORM IN NW GA THAT HAS HISTORY OF PRODUCING
DAMAGING WINDS. STORM MAY HAVE TRAVELED ALONG WRN PERIPHERY OF
WEDGE. WILL BE A FEW HOURS BEFORE NORTH GA SEES ANOTHER ROUND OF
POSSIBLE SVR STORMS. AS MENTIONED IN PREV DISCUSSION /SEE UPDATE
SECTION BELOW/ INGREDIENTS REMAIN IN PLACE FOR SVR STORMS TONIGHT
AND WED MORNING...GREATEST THREAT 03Z-15Z OR SO.
AS FRONT SWEEPS THRU WED AFTERNOON...SHOULD SEE RAPID END TO PRECIP
AND ERODING OF LOW CLOUDS. NOT MUCH CHC FOR WINTER PRECIP WED NIGHT
EVEN IN HIGHER ELEVATIONS. SOME IN ELEV ABOVE 2500FT MAY SEE A BRIEF
MIX OF LIGHT RAIN WITH SNOW FLURRIES BUT NO IMPACTS EXPECTED.
SNELSON
UPDATE...
/ISSUED AT 129 PM EST TUE DEC 23 2014/
FCST GRIDS UPDATED EARLIER THIS MORNING TO ACCOUNT FOR OBSERVED
TRENDS. 12Z MODELS...PARTICULARLY GFS...TOO QUICK LIFTING WARM
FRONT WHICH IS CURRENTLY LOCATED FROM AROUND COLUMBUS TO VIDALIA.
TEMPS WILL LIKELY REMAIN IN THE 40S IN NORTH GA AND 50S TO 60S
OVER MIDDLE GA.
COVERAGE OF RAINFALL OVER AL A LITTLE LESS THAN WHAT 12Z HIRES
MODELS INDICATING...POSSIBLY DUE TO LARGE EXPANDING AREA OF
CONVECTION OVER SRN AL AND SW GA. NEW 18Z CYCLE WPC QPF GUIDANCE
INDICATING ABOUT 1-2 INCHES OVER AREAS NORTH OF COLUMBUS TO MACON.
WILL REVIEW THIS BEFORE RELEASING FINAL FORECAST. BASED ON PREV
FCST AND ALREADY SOME REPORTS OF NUISANCE/MINOR FLOODING HAVE
ISSUED FLOOD WATCH FOR ALL OF CWA.
THREAT FOR SEVERE WX STILL IN PLACE THOUGH CONCERNED ABOUT
POSSIBLE UPSTREAM CONVECTION MENTIONED EARLIER DISRUPTING VERTICAL
WIND SHEAR AND INSTABILITY. THAT SAID...STILL SEEING FAIRLY STRONG
ISOLATED CELLS IN NRN/WRN AL ATTM WHERE MLCAPE VALUES TRYING TO
CREEP UP TO 250-500 J/KG. 0-1KM BULK SHEAR ONLY 20-30KTS IN AL.
12Z MODEL VALUES FOR TONIGHT SILL FAVORABLE FOR HIGH SHEAR LOW
CAPE CONVECTION AND QLCS MODES. NAM STILL HIGHER THAN GFS FOR
SHEAR AND MLCAPE...AVERAGING AROUND 100-300 J/KG MLCAPE AND 35-45
FOR 0-1KM BULK SHEAR. SHEAR DROPS SOME DURING DAY ON WED SO
TORNADO THREAT MAY LOWER ACCORDINGLY.
CONTINUING TO MONITOR.
SNELSON
LONG TERM /THURSDAY THROUGH TUESDAY/...
BEHIND A COLD FRONT THAT PUSHES EAST OF THE AREA EARLY THURSDAY
MORNING... WRAP AROUND CLOUDS AND MOISTURE MAY BE A BIT SLOW TO
CLEAR FROM WEST TO EAST THURSDAY MORNING DUE TO A LAGGING STRONG
UPPER DISTURBANCE THAT DOES NOT PUSH EAST OF THE STATE UNTIL EARLY
THURSDAY AFTERNOON. OTHERWISE... EXPECT DRY HIGH PRESSURE TO BUILD
OVER THE AREA THURSDAY AFTERNOON WITH CLEARING CONDITIONS AND HIGH
TEMPERATURES MOSTLY IN THE 50S. THE COOLEST TEMPERATURES WILL BE
FELT FRIDAY MORNING WITH LOWS MOSTLY IN THE 30S. THEN MODELS AGREE
ON THE SURFACE RIDGE SHIFTING EAST ON FRIDAY...AND ESTABLISHING A
WARMING...MOIST SOUTHERLY FLOW GOING INTO THE WEEKEND. THIS AHEAD OF
ANOTHER LOW PRESSURE SYSTEM THAT SHOULD BRING RAIN CHANCES TO THE
AREA OVER THE WEEKEND. LONG RANGE MODELS STILL SHOW SOME TIMING
DIFFERENCES... WITH THE FASTER GFS SPREADING SHOWERS INTO THE AREA
ON SATURDAY...AND HOLDING RAIN CHANCES ACROSS THE AREA INTO MONDAY
WHEN A SLOW MOVING COLD FRONT FINALLY TRAVERSES THE AREA. THE SLOWER
ECMWF HOLD RAIN CHANCES OFF UNTIL MAINLY SUNDAY...BUT THEN DOES SHOW
A COLD FRONT PUSHING ACROSS THE AREA MONDAY NIGHT-EARLY TUESDAY...
WITH BOTH SHOWING HIGH PRESSURE AND DRIER CONDITIONS IN CONTROL BY
TUESDAY. AT THIS TIME... LACK OF INSTABILITY AND STRONG UPPER
FORCING WARRANTS ONLY SHOWERS SO FAR WITH THIS SYSTEM... HOWEVER
THIS COULD CHANGE SO STAY TUNED.
39
HYDROLOGY...
DECIDED TO PLAY IT SAFE AND POST A FLOOD WATCH FOR MOST OF NORTH
AND CENTRAL GA THROUGH 8 PM WEDNESDAY DUE TO THE EXPECTED 2 TO 3
INCHES OF ADDITIONAL RAINFALL THROUGH WEDNESDAY AFTERNOON AHEAD OF
A COLD FRONT. ISOLATED HIGHER AMOUNTS ARE ALMOST CERTAIN... AND
WITH NEARLY 100 PERCENT RUNOFF OF ANY RAINFALL INTO CREEKS...
STREAMS AND RIVERS THIS TIME OF YEAR... RAPID RISES ARE
EXPECTED...THAT COULD RESULT IN FLOODING. IN ADDITION TO RIVER
FLOODING... ISOLATED FLASH FLOODING IS ALSO POSSIBLE DUE TO FALL
VEGETATION AND OTHER DEBRIS CLOGGING DRAINAGE SYSTEMS OR NARROWS
ALONG CREEKS AND STREAMS. ALL INTEREST ACROSS NORTH AND CENTRAL GA
SHOULD MONITOR CONDITIONS CLOSELY AND BE ALERT FOR POSSIBLE FLOOD
WARNINGS. THOSE LIVING IN AREAS PRONE TO FLOODING SHOULD BE
PREPARED TO TAKE ACTION SHOULD FLOODING DEVELOP. THE RAINFALL
SHOULD END FROM WEST TO EAST WEDNESDAY AFTERNOON AND GREATLY
LESSON THE THREAT OF FLOODING BY WEDNESDAY EVENING.
&&
.AVIATION...
06Z UPDATE...
MAIN LINE OF CONVECTION SWEEPING THROUGH THE AREA THIS MORNING
WITH SHOWERS CONTINUING BEHIND IT. WILL CONTINUE TO SEE SHOWERS
OFF AND ON IN THE ATL AREA THROUGH MIDDAY. WINDS ARE CURRENTLY OUT
OF THE EAST. THEY WILL TURN TO THE SE THEN SW AND EVENTUALLY WEST
THROUGH THIS TAF PERIOD. WIND SPEEDS EXPECTED TO INCREASE THIS
AFTERNOON AFTER THE FRONT PASSES THROUGH WITH 10KTS GUSTING TO
20KT. THE GUST WILL SUBSIDE OVER NIGHT. CEILINGS EXPECTED TO STAY
FAIRLY LOW THROUGH THE PERIOD LIFTING TO VFR BY THE VERY END OF
THIS TAF SET.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM TO HIGH CONFIDENCE ON ALL ELEMENTS.
01
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 66 40 55 32 / 100 30 5 0
ATLANTA 65 39 53 36 / 80 10 0 0
BLAIRSVILLE 58 35 49 29 / 80 30 5 0
CARTERSVILLE 64 37 51 29 / 80 10 0 0
COLUMBUS 66 40 56 34 / 80 10 5 0
GAINESVILLE 61 39 53 34 / 90 30 0 0
MACON 68 41 58 31 / 100 20 5 0
ROME 62 37 51 28 / 70 10 0 0
PEACHTREE CITY 66 37 54 28 / 80 10 0 0
VIDALIA 71 47 59 37 / 100 30 5 0
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH THROUGH THIS EVENING FOR THE FOLLOWING ZONES:
BALDWIN...BANKS...BARROW...BARTOW...BIBB...BLECKLEY...BUTTS...
CARROLL...CATOOSA...CHATTAHOOCHEE...CHATTOOGA...CHEROKEE...
CLARKE...CLAYTON...COBB...COWETA...CRAWFORD...CRISP...DADE...
DAWSON...DE KALB...DODGE...DOOLY...DOUGLAS...EMANUEL...FANNIN...
FAYETTE...FLOYD...FORSYTH...GILMER...GLASCOCK...GORDON...
GREENE...GWINNETT...HALL...HANCOCK...HARALSON...HARRIS...HEARD...
HENRY...HOUSTON...JACKSON...JASPER...JEFFERSON...JOHNSON...
JONES...LAMAR...LAURENS...LUMPKIN...MACON...MADISON...MARION...
MERIWETHER...MONROE...MONTGOMERY...MORGAN...MURRAY...MUSCOGEE...
NEWTON...NORTH FULTON...OCONEE...OGLETHORPE...PAULDING...PEACH...
PICKENS...PIKE...POLK...PULASKI...PUTNAM...ROCKDALE...SCHLEY...
SOUTH FULTON...SPALDING...STEWART...SUMTER...TALBOT...
TALIAFERRO...TAYLOR...TELFAIR...TOOMBS...TOWNS...TREUTLEN...
TROUP...TWIGGS...UNION...UPSON...WALKER...WALTON...WARREN...
WASHINGTON...WEBSTER...WHEELER...WHITE...WHITFIELD...WILCOX...
WILKES...WILKINSON.
TORNADO WATCH UNTIL 7 AM EST THIS MORNING FOR THE FOLLOWING
ZONES: CRISP...DODGE...DOOLY...MACON...MONTGOMERY...PULASKI...
SCHLEY...SUMTER...TELFAIR...WHEELER...WILCOX.
&&
$$
SHORT TERM...01
LONG TERM....BDL
AVIATION...01
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1151 PM CST TUE DEC 23 2014
.SHORT TERM /TONIGHT/...
ISSUED AT 313 PM CST TUE DEC 23 2014
PRECIP TRENDS WILL REMAIN THE PRIMARY FOCUS AGAIN TONIGHT. LIGHT
SNOW CONTINUES TO DRIFT NE-SW ACROSS THE NW HALF OF IA DRIVEN
MAINLY BY MID LEVEL KINEMATIC FORCING WITH WEAK DEFORMATION AND
DIFFERENTIAL POSITIVE VORTICITY ADVECTION NORTH OF IA PV ANOMALY
NOTED IN RAP ANALYSIS AND SUGGESTED BY PIVOT POINT IN WATER VAPOR
IMAGERY. THERE IS LITTLE THERMODYNAMIC COMPONENT AT THIS POINT.
PRECIP IS QUITE LIGHT WITH WEAK REFLECTIVITY...EVEN IN LONG
PULSE/VCP 31. WEBCAMS SHOW CURRENT VISIBILITY RESTRICTIONS ARE AS
MUCH DUE TO FOG AS SNOW WITH LITTLE SNOW NOTED. THIS WEAK FORCING
WILL REMAIN ESSENTIALLY STEADY STATE AS IT DRIFTS SLOWLY SOUTH AND
EAST THROUGH THE NIGHT BEFORE THE NEXT SHORT WAVE/PV ANOMALY
ROUNDS THE BASE OF THE TROUGH AND RE-ENERGIZES SYSTEM AGAIN TO OUR
SOUTH AND EAST TOWARD 12Z. SE FRINGE OF PRECIP SHIELD WILL BE A
RAIN/SNOW MIX WITH RAIN/SNOW LINE DRIFTING SE. ONLY LIGHT QPF
AMOUNTS AND TEMPERED SNOW RATIOS WILL RESULT ANY ADDITIONAL ACCUMS
BEING UNDER AN INCH AND MAINLY ON GRASSY OR ELEVATED SURFACES.
ROAD TEMPS REMAIN WET AND 35F PLUS SO MUCH OF SNOW WILL MELT ON
ROADS. MID LEVEL MOISTURE WILL BE LACKING SE WITH LITTLE ICE
INTRODUCTION SO PRECIP WILL GENERALLY REMAIN LIQUID/DRIZZLE SOUTH
AND EAST OF DES MOINES.
.LONG TERM /WEDNESDAY THROUGH TUESDAY/...
ISSUED AT 313 PM CST TUE DEC 23 2014
THE LONG TERM PORTION OF THE FCST PD WILL BE CHARACTERIZED BY
MINIMAL PRECIPITATION...ALONG WITH ABOVE NORMAL TEMPERATURES LATE
THIS WEEK FOLLOWED BY TEMPERATURES GOING BELOW NORMAL BEGINNING
THIS WEEKEND AND CONTINUING INTO NEXT WEEK.
MODELS IN GOOD AGREEMENT WITH THE CENTRAL CONUS SHORTWAVE ENERGY
DEVELOPING A SFC LOW ACROSS THE SOUTHERN U.S. TONIGHT...BRINGING
IT NORTH-NORTHEAST INTO THE EASTERN GREAT LAKES AND DEEPENING BY
THURSDAY. GREATEST SYNOPTIC FORCING AND MOISTURE WILL REMAIN TO
THE EAST OF THE CWA. MODELS SHOWING REMNANT AREA OF WEAK LIFT AND
MOISTURE IN E/SE CWA THRU WED MORNING...SO HAVE KEPT CHC/SLIGHT
CHANCE POPS THERE. PCPN IS EXPECTED TO BE LIGHT.
ATTENTION THEN TURNS TO THE NEXT WX SYSTEM TO AFFECT OUR REGION.
CENTRAL U.S. SHORTWAVE LIFTS OUT AND ANOTHER SHORTWAVE ENTERS THE
WESTERN U.S. BY THURSDAY. MODELS BEGIN DIVERGING ON THE SPEED AND
STRENGTH OF THIS SHORTWAVE ONCE IT ARRIVES. GFS PRESENTS A FASTER
AND WEAKER SOLUTION...WITH THE ECMWF HOLDING THE ENERGY BACK FOR
LONGER. THE DIVERGING SOLUTIONS IMPACT SFC FEATURES AS WELL...WITH
THE GFS BRINGING A STRONGER SFC SYSTEM THROUGH OUR REGION AND
FASTER VS. THE ECMWF. HAVE TRENDED SLOWER THAN THE GFS GIVEN ITS
RECENT PERFORMANCE...BRINGING -SN INTO THE CWA BEGINNING 12Z FRI.
PRIOR TO THE PRECIP/S ARRIVAL...THOUGH...STRONG WAA WILL PUSH
THURSDAY/S MAXES INTO THE MIDDLE 30S AND 40S. ATTM THE BULK OF THE
PRECIP IS EXPECTED TO REMAIN NW OF THE CWA...WITH BEST COMBINATION
OF FORCING AND MOISTURE MOVING ACROSS THE CWA FRI AFTN AND FRIDAY
NIGHT. ALTHOUGH POPS ARE RELATIVELY LOW...THERE IS THE POTENTIAL
FOR A BRIEF PERIOD OF LIFT TO COINCIDE WITH ELEVATED RH LEVELS
WITHIN THE DGZ ESPECIALLY ACROSS NW IOWA.
MODEL SOLUTIONS DIVERGE FURTHER WITH TIME INTO THE WEEKEND SO
FORECAST CONFIDENCE DECREASES. GFS KEEPS OUR REGION IN CYCLONIC
FLOW WITH WEAK SHORTWAVES WHILE THE ECMWF BRINGS MORE FOCUSED
SHORTWAVE ENERGY THROUGH OUR REGION MONDAY. HAVE TENDED TOWARD THE
ECMWF AND HAVE SLIGHT CHANCE POPS FOR THIS TIME PD. LITTLE IF ANY
SNOWFALL ACCUMULATIONS ARE AGAIN EXPECTED GIVEN THE BEST FORCING
BEING OUT OF PHASE WITH ELEVATED MOISTURE LEVELS. TEMPERATURES
WILL BEGIN A DOWNWARD TEND AS NORTHWEST FLOW ALOFT PREVAILS.
&&
.AVIATION...24/06Z
ISSUED AT 1146 PM CST TUE DEC 23 2014
BAND OF LIFR CONDITIONS IN SNOW AND STRATUS WILL CONTINUE TO SINK
SOUTHEAST WITH CONDITIONS BECOMING MVFR FROM THE NORTHWEST LATE
TONIGHT AND WED. VFR CONDITIONS WILL REACH THE FAR WEST LATE IN
THE TAF PERIOD AS HIGH PRESSURE RIDGE AXIS REACHES CENTRAL IA.
OUTLOOK...VFR CONDITIONS WILL OVERSPREAD THE AREA WEDNESDAY NIGHT
AND CHRISTMAS DAY WITH VFR CONTINUING INTO FRIDAY.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...SMALL
LONG TERM...ZOGG
AVIATION...MS DEC 14
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1145 PM CST TUE DEC 23 2014
.UPDATE...
ISSUED AT 943 PM CST TUE DEC 23 2014
BAND OF SNOW CONTINUES FROM PORTIONS OF NORTHEAST-CENTRAL-SOUTHWEST
IA WITHIN ZONE OF WEAK ISENTROPIC LIFT ON BACKSIDE OF UPPER TROUGH
AXIS. THIS LIFT DEPICTED WELL ON 295K SFC OF NAM AND RAP MODELS
AND IS SHOWN TO GRADUALLY WEAKEN OVERNIGHT REMAINING MAINLY WEST OF
CWA ALTHOUGH POSSIBLY BRUSHING FAR WEST SECTIONS... ALONG/W OF
IIB-VTI-OOA LINE WITH FLURRIES OR VERY LIGHT SNOW. OTHERWISE...SOME
PATCHY DRIZZLE WAS NOTED ALONG MISSISSIPPI RIVER AHEAD OF FRONT
AND THIS MAY CONTINUE NEXT FEW HOURS BEFORE SHIFTING EAST WITH THE
FRONT... THEN ASIDE FROM FAR WESTERN CWA REST OF THE NIGHT APPEARS
TO BE MAINLY DRY. AS RESULT... HAVE UPDATED TO REMOVE ANY MEASURABLE
POPS REST OF TONIGHT. ALSO...WITH CONSIDERABLE CLOUDS AND FAIRLY
WEAK COLD ADVECTION HAVE NUDGED UP MINS WITH MOST AREAS STAYING AT
OR ABOVE 32F.
AS FOR TOMORROW /CHRISTMAS EVE/ SYSTEM... SOME OF THE LATEST MODEL
GUIDANCE OF RAP...NAM AND GFS MODELS TAKE THE STORM SLIGHTLY
FURTHER EAST AND SUGGEST MAY NOT EVEN SEE FAR EAST BRUSHED BY ANY
SNOW. MAY SEE SOME FLURRIES AND POSSIBLY FEW SNOW SHOWERS IF
SUFFICIENT MOISTURE DEPTH BUT ASIDE FROM BRIEF REDUCTION IN VSBY
(SHOULD THE SNOW SHOWERS OCCUR) NO IMPACTS EXPECTED WITH TEMPS ABOVE
32F. HAVING SAID THAT... ANYONE WITH TRAVEL INTERESTS TO OUR EAST
TOMORROW WILL WANT TO STAY UPDATED AS POSSIBILITY OF IMPACTS TO TRAVEL
FROM WET/SLUSHY ROADS AND LIMITED VISBILITIES AT TIMES.
&&
.SYNOPSIS...
ISSUED AT 312 PM CST TUE DEC 23 2014
SYNOPSIS...AT 3 PM CST..A WEAK COLD FRONT BISECTED THE DVN CWA.
THICK OVERCAST WAS OBSERVED TO THE NW OF THE BOUNDARY WITH TEMPS
IN THE MID TO UPPER 30S. TO THE SE...IN A SOUTHWEST SFC WIND FLOW
SKIES WERE SCT TO BKN AND TEMPS WERE IN THE LOWER TO MIDDLE
40S...AND A LIGHT RAIN SHOWERS WAS LOCATED NEAR IOWA CITY. A
DEVELOPING SFC LOW PRESSURE SYSTEM WILL MOVE NORTHEASTWARD ON
WEDNESDAY AFTN AND NIGHT...BUT WILL REMAIN WELL EAST OF E IOWA AND
W ILLINOIS. THERE IS A CHANCE FOR LIGHT SNOW ACCUMULATIONS ACROSS
THE FAR EASTERN CWA WITH THIS SYSTEM. HOWEVER HIGH TEMPS IN THE
MID 30S SHOULD LIMIT THE OVERALL IMPACT FROM ANY SNOW THAT FALLS.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 312 PM CST TUE DEC 23 2014
TONIGHT...AS THE COLD FRONT SLIDES EAST OF THE AREA AFTER MIDNIGHT
SFC WINDS WILL VEER FROM THE SW TO THE NW AND THE STRATUS WILL
OVERSPREAD THE ENTIRE CWA. NAM FORECAST SFC DEWPOINT DEPRESSIONS ARE
NEAR 1-2 F OVERNIGHT BUT NW FLOW WILL LEAD TO SLOWLY DECREASING
MOISTURE THROUGH THE NIGHT SO NOT EXPECTING MUCH FOR FOG. A FEW
LIGHT RAIN/SNOW SHOWERS WILL BE POSSIBLE AS THE 850 MB TROUGH AXIS
SWINGS THROUGH BUT MANY AREAS WILL REMAIN DRY. NO SNOW ACCUMULATION
IS EXPECTED.
WEDNESDAY...PROMINENT LONGWAVE TROUGH ACROSS THE CENTRAL U.S.
DIPPING ALL THE WAY DOWN TO THE GULF OF MEXICO ALONG WITH A
STRENGTHENING JET STREAK ON ITS EASTERN FLANK AND BURGEONING
CONVECTION ACROSS THE SOUTHERN U.S. WILL INDUCE AN AREA OF
CYCLOGENESIS IN THE WESTERN OHIO VALLEY/GREAT LAKES. THE SFC LOW
IS FORECAST TO TRACK FROM N LOUISIANA TO N LOWER MICHIGAN.
MODEL DISCREPANCIES...12.23/12Z NAM AND GFS WERE THE FURTHEST WEST
WITH THE LOW TRACK FROM NE INDIANA TO NE LOWER MICHIGAN AND HAVE
THE GREATEST POTENTIAL FOR A PERIOD OF SNOW IN MY EASTERN CWA. THE
ECMWF AND GEM ARE FURTHER EAST WITH THE TRACK AND BRING VERY LIGHT
SNOW POTENTIAL WITH LESS THAN 0.10 INCHES OF QPF IN MY EASTERN
COUNTIES. THE HI-RES WRF-NMM HAS THE STEADY PRECIP DEFORMATION
BAND AFFECTING EASTERN BUREAU AND ALL OF PUTNAM COUNTY WITH STRONG
700-500 MB FRONTOGENESIS. THE 18Z NAM HAS NOW SHIFTED SLIGHTLY
EAST SO MODELS OVERALL IN FAIRLY GOOD AGREEMENT AT THIS POINT.
CWA IMPACTS...BEST CHANCES FOR ACCUMULATING SNOW WILL BE IN BUREAU
AND PUTNAM COUNTIES. A FEW FACTORS TO CONSIDER ARE THE RELATIVELY
WARM GROUND WITH THE PROLONGED PERIOD OF TEMPS IN THE 40S THE LAST
FEW DAYS AND FORECAST MAX TEMPS ABOVE FREEZING TOMORROW AFTN.
SINCE THERE IS NO COLD AIR IN PLACE...DYNAMIC COOLING IS NECESSARY
FOR SNOW TO OCCUR. BEST FORECAST AT THIS TIME IS FOR PERIOD OF
LIGHT SNOW TO IMPACT THE FAR EAST DURING THE AFTN WITH
ACCUMULATIONS POSSIBLY UP TO AN INCH OR TWO OF WET SNOW WITH SLRS
AT 9:1 OR SLIGHTLY LOWER...AND FLURRIES OR SCT SNOW SHOWERS
POSSIBLE ELSEWHERE.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 245 PM CST TUE DEC 23 2014
MAIN FORECAST CONCERN IN THE EXTENDED PERIOD IS THE NEXT SYSTEM
THAT WILL AFFECT THE AREA ON FRIDAY AND INTO SATURDAY MORNING.
THIS SYSTEM LOOKS TO BRING US A CHANCE OF RAIN AND SNOW MIXED IN
FOR FRIDAY NIGHT INTO SATURDAY.
CHRISTMAS DAY IS A DRY DAY BETWEEN TWO STORM SYSTEMS. UNFORTUNATELY
AT THIS TIME...IT LOOKS LIKE WE WILL HAVE A BROWN CHRISTMAS AND IT
DOES NOT LOOK LIKE WE WILL HAVE ANY APPRECIABLE SNOW IN THE
EXTENDED. WE COULD SEE THE SUN LATER IN THE DAY ON CHRISTMAS EVE.
USED CONSRAW AS A STARTING POINT FOR TEMPERATURES SINCE BOI VERIFY
SUGGESTED IT HAS VERIFIED THE BEST RECENTLY.
FRIDAY...WARM AIR RETURNS TO THE AREA AS A LOW PRESSURE SYSTEM
PASSES TO OUR NORTH. TEMPERATURES SHOULD BE IN THE HIGH 40S. CLOUDS
RETURN LATER IN THE DAY ON FRIDAY AS ANOTHER STORM SYSTEM MAKES ITS
WAY INTO THE AREA. MODELS DIFFER ON THE TIMING OF PRECIP. THE GFS
HAS PRECIP ENTER THE CWA BEFORE 00Z SATURDAY. THE GFS APPEARS TO BE
FASTER THAN ALL OF THE MODELS...THIS IS THE CASE IN RESPECT TO THE
GEFS AS WELL. THE GEM AND ECMWF ARE CLOSER TO THE GEFS MEANS. SO
DECIDED TO EXCLUDE THE GFS FORECAST FOR PRECIP DURING THIS TIME.
LOOKS LIKE PRECIP MAKES ITS WAY IN AS A COLD FRONT APPROACHES THE
AREA. H92 TEMPS AND MODEL SOUNDINGS FROM THE GFS SUGGEST SNOW AT 03Z
ACROSS THE AREA...HOWEVER THE ECMWF WHICH HAS A MORE REASONABLE
SOLUTION SUGGESTS RAIN ACROSS EASTERN PORTIONS OF THE CWA FROM 00Z
TO 03Z WITH A RASN LINE MOVING EAST THROUGH THAT TIME. BY 12Z MOST
OF THE PRECIP WILL BE SNOW...WITH A FEW AREAS IN FAR EASTERN ZONES
STILL A RASN MIX.
LOOKING TOWARDS THE END OF THE EXTENDED PERIOD. A POLAR AIRMASS IS
FORECAST TO OCCUPY THE AREA TOWARDS NEW YEARS EVE. MODELS AGREE
THAT FLOW WILL BE OUT OF THE NW...SO TEMPS SHOULD BE COOLER THE
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1135 PM CST TUE DEC 23 2014
ANTICIPATE WIDESPREAD IFR TO LIFR CONDITIONS OVERNIGHT INTO WED AM
WITH ARRIVAL OF COLDER AIR AND ABUNDANT LOW LEVEL MOISTURE. SOME
IMPROVEMENT TO MVFR EXPECTED WED PM AND POSSIBLY INTO VFR WEST OF
THE MISSISSIPPI RIVER WED EVE. AN UPPER LEVEL TROUGH WILL MOVE
ACROSS THE REGION ON WED AND MAY BRING FLURRIES AND A FEW SNOW
SHOWERS TO THE AREA... BUT ENOUGH UNCERTAINTY WITH MOISTURE DEPTH
AND FORCING DUE TO DEEPENING LOW PASSING WELL EAST OF THE TERMINALS
PRECLUDES ANY MENTION MORE THAN JUST FEW FLURRIES ATTIM. TIGHTENING
PRESSURE GRADIENT WILL RESULT IN INCREASING NORTHWEST WINDS 10-15+
KTS AND GUSTY BY WED PM.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...05
SYNOPSIS...UTTECH
SHORT TERM...UTTECH
LONG TERM...GIBBS
AVIATION...05
AREA FORECAST DISCUSSION
NWS TOPEKA KS
543 PM CST Thu Dec 25 2014
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Friday)
Issued at 236 PM CST THU DEC 25 2014
This afternoon the winds begin to diminish with the loss of
daytime heating. This should occur some time right around sunset
therefore kept the wind advisory as it stands. During the evening
hours there may be occasional gusts as the boundary layer tries to
decouple over southeast portions of the forecast area. This is
where the pressure gradient remains the strongest relatively
speaking. Further west in central KS a front approaches from the
northwest leading to a lesser gradient there. The front slides
through the area overnight tonight causing a brief period of light
winds. Low temperatures tonight dip into the upper 20s in north
central KS behind the front, and only drop into the upper 30s in
east central KS.
The front should be exiting the forecast area shortly after
sunrise tomorrow. During the day tomorrow a lead shortwave will
eject from the Central Rockies, which will bring precip into north
central KS in the late afternoon hours. Ahead of the system gulf
moisture surges north into eastern KS where it will advect over
the front to our south. Type of precipitation is tricky, with
surface temperatures very near the freezing mark. Precipitation
should start out as rain or drizzle early afternoon, but may cross
over to a light freezing drizzle in the north central counties for
a few hours in the late afternoon as the front deepens, and before
saturation in the snow growth layer occurs. Across eastern KS the
soundings indicate that most of the lift will be located in the
low levels leading to more of a light rain or drizzle with temps
above freezing. Do not expect much measurable precip before 00Z
Sat. In fact the NAM indicates that most locations could receive
mainly drizzle during the afternoon hours.
.LONG TERM...(Friday Night through Thursday)
Issued at 236 PM CST THU DEC 25 2014
Friday evening into Saturday...Think precipitation will switch
over to a light snow by the evening hours. Piece of stronger
energy clips these NW counties in the overnight hours, and may
bring an inch of snow to that area, with decreasing amount to the
south and east. Expect only a trace to possibly a dusting south of
the interstate. Precipitation moves eastward quickly as the wave
opens and lifts to the northeast, leaving highs in the upper 20s
to low 30s, with lows falling into the teens Saturday night.
Sunday bring a day with high temperatures near normal before the
next strong cold front sweeps into the area on Monday. Monday may
also see some high temperatures reach back up into the middle 30s
before the front drives through in the afternoon hours. GFS
solution is faster, and would cool down quicker. Overnight Monday
into Tuesday brings a chance for another brief round of snow as
the strong high continues to slide down the front range. Chances
are slightly better in the western counties where better moisture
and lift are present. Highs drop to single digits to teens, with
highs on Tuesday in the teens most areas save the far southeast.
Very cold lows in the single digits settle in for Tuesday night as
1041mb high centers over western Kansas.
Larger scale pattern drops energy southwestward over southern
California with a broad large scale upper trof over the eastern
North American coast. This leaves the area under generally
westerly flow and surface temperatures try to moderate back into
the 20s on Wednesday and 30s for Thursday.
&&
.AVIATION...(For the 00Z TAFs through 00Z Friday Evening)
Issued at 543 PM CST THU DEC 25 2014
VFR expected through 14Z Friday with cigs becoming mvfr 15Z-18Z at
the terminals behind surface cold front. Surface winds decoupling
and backing to a southerly direction at 00Z, however latest 00Z raob
winds show winds near 2kft from the southwest at 47kts. RUC soundings
show winds near 2kft to increase to near 50 kts through 06Z before
weakening. Will include llws for TOP and FOE terminals through
06Z.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Sanders/67
LONG TERM...67
AVIATION...53
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
158 PM EST WED DEC 24 2014
.UPDATE...
ISSUED AT 158 PM EST WED DEC 24 2014
THE COLD FRONT IS MOVING INTO OUR AREA...NOW LOCATED NEAR KEKQ AND
JUST WEST OF KLEX. TEMPERATURES HAVE SOARED INTO THE UPPER 60S OUT
AHEAD OF THE BOUNDARY...THANKS TO SOME HOLES IN THE PRECEDING MID AND
HIGH LEVEL CLOUD DECK. A NICE BAND OF SHOWERS HAVE CONTINUED TO
DEVELOP ALONG AND BEHIND THE COLD FRONT. HAVE TAKEN POPS UP TO
CATEGORICAL IN THE WEST...AND THEN ALLOWED FOR A GRADUAL DIMINISHMENT
AS THE LINE COMES EAST AS THE FRONT STARTS TO SHEAR OUT WITH TIME.
UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 1103 AM EST WED DEC 24 2014
THE COLD FRONT IS CURRENTLY ALIGNED FROM IN/OH BORDER DOWN THROUGH
NEAR CENTRAL KENTUCKY...HAVING JUST PASSED THROUGH BWG...BUT STILL
SLIGHTLY WEST OF SDF. PLENTY OF SHOWER ACTIVITY IS FILLING IN ALONG
AND BEHIND THE FRONT...AND HAVE BEEFED UP POPS TO LIKELY FOR MOST AS
IT MAKES IT WAY TOWARDS EASTERN KENTUCKY THIS AFTERNOON. ALSO ADDED A
FEW MORE COUNTIES TO THE WIND ADVISORY...MAINLY HIGHLIGHTING
ELEVATIONS ABOVE 1500 FEET...CLOSER TO THE STRONGER WINDS OCCURRING
ALOFT. SPC STILL HIGHLIGHTS A MARGINAL THREAT OF STRONGER WIND GUSTS
ASSOCIATED WITH MORE INTENSE SHOWERS OR ISOLATED THUNDERSTORMS...SO
WILL CONTINUE TO ADVERTISE THIS POSSIBILITY ACROSS MUCH OF THE AREA
AS WELL IN THE HWO. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 648 AM EST WED DEC 24 2014
UPDATED TO LOWER POPS THIS MORNING AS SOUTHEAST FLOW CONTINUES TO
STRENGTHEN WITH CLOUD HEIGHTS CONTINUING TO GO UP. THEY ARE NOW OVER
10KFT. THUS...CHANCES FOR MEASURABLE RAIN ARE DECREASING THROUGH THE
MORNING HOURS. BEST CHANCE OF RAIN STILL LOOKS TO COME WITH THE COLD
FRONT AS IT CROSSES THE AREA THIS AFTERNOON. LATEST HI-RES MODELS
CONTINUE TO SHOW THE POSSIBILITY OF A FEW THUNDERSTORMS AS THE FRONT
PUSHES ACROSS OUR AREA. SHOULD WARM UP NICELY GIVEN THE SOUTHEAST
FLOW AND LIMITED LOW CEILINGS THIS MORNING. WOULDN`T BE SURPRISED TO
SEE US GET EVEN WARMER THAN THE FORECAST CURRENTLY REFLECTS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 316 AM EST WED DEC 24 2014
AREA OF LOW PRESSURE IS NOW STARTING TO MAKE ITS MOVE NORTH ACROSS
CENTRAL KENTUCKY...AND WILL END UP OVER SOUTHEAST MICHIGAN BY THIS
EVENING. STRONG LIFT ASSOCIATED WITH THE LOW PRESSURE SYSTEM WILL
SPREAD ACROSS THE AREA THROUGH DAYBREAK WITH RAIN BECOMING WIDESPREAD
ONCE AGAIN AFTER A BRIEF LULL OVER THE PAST FEW HOURS. HRRR AND RAP
ARE IN GOOD AGREEMENT THAT THIS LIFT WILL EXIT TO THE NORTH BY 9 OR
10 AM...WITH ANOTHER LULL IN PRECIPITATION EXPECTED THROUGH MIDDAY.
WITH THE MIDDAY LULL IN PRECIPITATION...HIGHS WILL WARM INTO THE 60S
FOR ONE MORE DAY.
FINALLY AS THE LOW SHIFTS NORTH THOUGH...A STRONG COLD FRONT WILL
PUSH EAST ACROSS THE AREA THIS AFTERNOON. WITH THE MILD
TEMPERATURES...WE MAY GENERATE SOME WEAK INSTABILITY TO SUPPORT
CONVECTIVE SHOWERS DEVELOPING ALONG THE FRONT AS IT PUSHES ACROSS THE
AREA. WHILE THUNDER CHANCES REMAIN LOW...CANNOT RULE OUT SOME THUNDER
WITH THE STRONGER CELLS...ESPECIALLY ACROSS NORTHERN KENTUCKY. GIVEN
THE ABUNDANCE OF MID LEVEL DRY AIR...AND STRONG 850MB WINDS AROUND 45
KNOTS...WE COULD SEE THE POTENTIAL FOR SOME HIGHER WINDS TO GET MIXED
DOWN WITH THE SHOWERS. HOWEVER...EVEN WITHOUT THE CONVECTIVE SUPPORT
FOR WINDS...THE SYNOPTIC SETUP BEHIND THE FRONT SHOULD SUPPORT 40+
MPH WINDS...ESPECIALLY ACROSS THE NORTHERN HALF OF THE AREA.
THUS...WILL GO AHEAD WITH A WIND ADVISORY FOR THE NORTHERN HALF OF
THE AREA. CONDITIONS ARE MORE MARGINAL FARTHER SOUTH...BUT A WIND
ADVISORY FOR THE HIGH TERRAIN NEAR THE VIRGINIA BORDER ALSO SEEMS IN
ORDER GIVEN THE STRONG WINDS AT 850MB. BEST THREAT FOR THE HIGHER
WINDS WILL BE AFTER 17Z AND BEFORE 03Z TONIGHT.
CONDITIONS WILL QUITE DOWN SOME THIS EVENING AS SUBSIDENCE SPREADS IN
BEHIND THE DEPARTING FRONT. HOWEVER...A SHORTWAVE TROUGH WILL PUSH
EAST ACROSS THE AREA LATE TONIGHT...WITH THE MOISTURE DEPTH
INCREASING TO SUPPORT SOME LIGHT RAIN/DRIZZLE. COLDER AIR WILL ALSO
BE SPILLING INTO THE AREA TONIGHT BEHIND THE FRONT. WHILE MOST AREAS
WILL STAY MILD ENOUGH FOR JUST RAIN...THE HIGHER TERRAIN IN THE
SOUTHEAST WILL SUPPORT SOME SNOW CHANCES. IN FACT...CONDITIONS ALIGN
GOOD ENOUGH TONIGHT WE COULD SEE A LIGHT COATING OF SNOW ON THE HIGH
TERRAIN ABOVE 2500 FEET LATE TONIGHT.
HEIGHTS WILL BE QUICK TO BUILD BACK ACROSS THE AREA ON CHRISTMAS.
CLOUDS MAY BE STUBBORN THROUGH THE FIRST HALF OF THE DAY...BUT WE
SHOULD DEFINITELY SEE A DECREASING TREND THROUGH THE AFTERNOON AND
EVENING AS THE RIDGE CENTERS ITSELF OVER THE REGION. HIGHS WILL
STRUGGLE TO WARM GIVEN THE ABUNDANCE OF CLOUDS THROUGH THE FIRST HALF
OF THE DAY...SO PLAN TO KEEP HIGHS LIMITED TO THE LOW TO MID 40S WITH
30S ON THE HIGHER TERRAIN IN THE SOUTHEAST.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 420 AM EST WED DEC 24 2014
THE PERIOD IS EXPECTED TO BEGIN WITH A CLOSED UPPER LOW CONTINUING TO
DEPART TO THE NORTHEAST OF THE REGION WITH UPPER LEVEL RIDGING
BUILDING ACROSS THE AREA AT THE START OF THE PERIOD. FURTHER TO THE
WEST A TROUGH IS EXPECTED TO EXTEND FROM THE NORTHERN PLAINS SOUTH
INTO THE SOUTHERN ROCKIES AND NORTHERN MEXICO. SFC AND UPPER LEVEL
RIDGING WILL GRADUALLY WORK ACROSS THE AREA FOR THU NIGHT INTO FRIDAY
AND THEN DEPART TO THE EAST FRIDAY NIGHT INTO SATURDAY. MEANWHILE A
SHORTWAVE TROUGH IS ANTICIPATED TO EJECT FROM THE WESTERN TROUGH
ACROSS THE PLAINS TOWARD THE GREAT LAKES FROM FRIDAY INTO SATURDAY.
THIS WILL LEAD TO GRADUALLY LOWERING HEIGHTS ACROSS THE GREAT LAKES
AND OH VALLEY AND A COLD FRONT DROPPING TOWARD THE REGION TO START
THE WEEKEND. THIS SHOULD BEGIN THE START OF AN UNSETTLED PERIOD.
OVER TIME...A RATHER BROAD TROUGH IS EXPECTED TO DEVELOP FROM CENTRAL
CANADA SOUTH INTO THE ROCKIES AND THEN EAST INTO THE EASTERN CONUS.
MODELS VARY FROM RUN TO RUN AND MODEL TO MODEL WITH THE HANDLING OF
INDIVIDUAL SHORTWAVES IN WEST SOUTH TO SOUTHWEST FLOW DURING THIS
PERIOD AND THE INTERACTION WITH A BAROCLINIC ZONE...THE FRONT THAT
MOVES INTO THE AREA EARLY IN THE WEEKEND...RESULTING IN SFC WAVES
DEVELOPING ALONG THE FRONT. THE ECMWF IS GENERALLY SLOWER BRINGING
THIS FRONT ACROSS THE AREA AND IS ALSO STRONGER AND FURTHER SOUTHEAST
WITH A SFC WAVE SUN NIGHT INTO MONDAY. AS THIS LAST SYSTEM DEPARTS AN
ARCTIC BOUNDARY SHOULD APPROACH THE AREA TUE OR WED.
DUE TO AN OVERALL LACK OF COLDER AIR FOR MOST OF THE PERIOD...MUCH OF
THE PRECIPITATION SHOULD FALL AS RAIN...ALTHOUGH SOME SNOW MAY MIX IN
ON SUNDAY NIGHT INTO EARLY ON MONDAY IN THE HIGHEST TERRAIN AND NORTH
OF THE MTN PARKWAY. A MIX OF RAIN AND SNOW WILL REMAIN POSSIBLE INTO
THE DAY ON TUESDAY AS WE HELD ONTO SLIGHT CHANCE POPS TO ACCOUNT FOR
THE ECMWF RUN. BOTH THE GFS AND ECMWF RUNS SUPPORT A WET END TO THE
WEEKEND.
AS FOR TEMPERATURES...THE PATTERN FAVORS A RIDGE VALLEY TEMPERATURE
SPLIT ON THU NIGHT AS SKIES WILL HAVE CLEARED OR SHOULD BE CLEARING
AS SFC AND UPPER LEVEL RIDGING WORK INTO THE AREA. A RELATIVELY DRY
AIR MASS AND A DOWNSLOPE COMPONENT SHOULD LEAD TO A RATHER MILD DAY
ON FRIDAY...ESPECIALLY FOR VALLEYS NEAR THE VA BORDER. THE DEPARTING
RIDGE SHOULD AGAIN FAVOR MILDER LOWS ON FRI NIGHT...BUT YET ANOTHER
RIDGE/VALLEY SPLIT. SATURDAY SHOULD AGAIN BE MILD AHEAD OF THE
BOUNDARY. WITH THE BAROCLINIC ZONE OVER OR NEAR THE REGION A
GENERALLY NW TO SOUTH OR SOUTHEAST GRADIENT IN TEMPERATURES IS
ANTICIPATED FOR THE REMAINDER OF THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 158 PM EST WED DEC 24 2014
VFR CONDITIONS OUT AHEAD OF THE COLD FRONT WILL QUICKLY CRASH TO MVFR
AND EVENTUALLY IFR FROM WEST TO EAST THROUGH THE REST OF THIS
AFTERNOON...WITH A 2-3 HOUR PERIOD OF SHOWERS. SUSTAINED SOUTH TO
SOUTHWEST WINDS OF 10 TO 15 KTS...WITH GUSTS UP TO 25 KTS...WILL TURN
TO THE WEST AT 10 TO 25 KTS...WITH GUSTS IN THE 25 TO KTS RANGE.
THESE HIGHER WINDS WILL LAST AN HOUR OR SO BEFORE THE GUSTS SETTLE
BACK DOWN TO AROUND 20 KTS THROUGH THIS EVENING. ONCE THE FRONTAL
SHOWERS EXIT OFF TO THE EAST THIS EVENING...SOME LIGHTER PRECIPTATION
WILL BE POSSIBLE OVERNIGHT. WSW WINDS WILL DIMINISH TOWARDS
DAWN...WITH IFR CEILINGS LIKELY IMPROVING TOWARDS MVFR AS WELL.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 10 PM EST THIS EVENING FOR KYZ044-050>052-
058>060-068-069-088-104-106>120.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...KAS
LONG TERM...JP
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1103 AM EST WED DEC 24 2014
.UPDATE...
ISSUED AT 1103 AM EST WED DEC 24 2014
THE COLD FRONT IS CURRENTLY ALIGNED FROM IN/OH BORDER DOWN THROUGH
NEAR CENTRAL KENTUCKY...HAVING JUST PASSED THROUGH BWG...BUT STILL
SLIGHTLY WEST OF SDF. PLENTY OF SHOWER ACTIVITY IS FILLING IN ALONG
AND BEHIND THE FRONT...AND HAVE BEEFED UP POPS TO LIKELY FOR MOST AS
IT MAKES IT WAY TOWARDS EASTERN KENTUCKY THIS AFTERNOON. ALSO ADDED A
FEW MORE COUNTIES TO THE WIND ADVISORY...MAINLY HIGHLIGHTING
ELEVATIONS ABOVE 1500 FEET...CLOSER TO THE STRONGER WINDS OCCURRING
ALOFT. SPC STILL HIGHLIGHTS A MARGINAL THREAT OF STRONGER WIND GUSTS
ASSOCIATED WITH MORE INTENSE SHOWERS OR ISOLATED THUNDERSTORMS...SO
WILL CONTINUE TO ADVERTISE THIS POSSIBILITY ACROSS MUCH OF THE AREA
AS WELL IN THE HWO. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 648 AM EST WED DEC 24 2014
UPDATED TO LOWER POPS THIS MORNING AS SOUTHEAST FLOW CONTINUES TO
STRENGTHEN WITH CLOUD HEIGHTS CONTINUING TO GO UP. THEY ARE NOW OVER
10KFT. THUS...CHANCES FOR MEASURABLE RAIN ARE DECREASING THROUGH THE
MORNING HOURS. BEST CHANCE OF RAIN STILL LOOKS TO COME WITH THE COLD
FRONT AS IT CROSSES THE AREA THIS AFTERNOON. LATEST HI-RES MODELS
CONTINUE TO SHOW THE POSSIBILITY OF A FEW THUNDERSTORMS AS THE FRONT
PUSHES ACROSS OUR AREA. SHOULD WARM UP NICELY GIVEN THE SOUTHEAST
FLOW AND LIMITED LOW CEILINGS THIS MORNING. WOULDN`T BE SURPRISED TO
SEE US GET EVEN WARMER THAN THE FORECAST CURRENTLY REFLECTS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 316 AM EST WED DEC 24 2014
AREA OF LOW PRESSURE IS NOW STARTING TO MAKE ITS MOVE NORTH ACROSS
CENTRAL KENTUCKY...AND WILL END UP OVER SOUTHEAST MICHIGAN BY THIS
EVENING. STRONG LIFT ASSOCIATED WITH THE LOW PRESSURE SYSTEM WILL
SPREAD ACROSS THE AREA THROUGH DAYBREAK WITH RAIN BECOMING WIDESPREAD
ONCE AGAIN AFTER A BRIEF LULL OVER THE PAST FEW HOURS. HRRR AND RAP
ARE IN GOOD AGREEMENT THAT THIS LIFT WILL EXIT TO THE NORTH BY 9 OR
10 AM...WITH ANOTHER LULL IN PRECIPITATION EXPECTED THROUGH MIDDAY.
WITH THE MIDDAY LULL IN PRECIPITATION...HIGHS WILL WARM INTO THE 60S
FOR ONE MORE DAY.
FINALLY AS THE LOW SHIFTS NORTH THOUGH...A STRONG COLD FRONT WILL
PUSH EAST ACROSS THE AREA THIS AFTERNOON. WITH THE MILD
TEMPERATURES...WE MAY GENERATE SOME WEAK INSTABILITY TO SUPPORT
CONVECTIVE SHOWERS DEVELOPING ALONG THE FRONT AS IT PUSHES ACROSS THE
AREA. WHILE THUNDER CHANCES REMAIN LOW...CANNOT RULE OUT SOME THUNDER
WITH THE STRONGER CELLS...ESPECIALLY ACROSS NORTHERN KENTUCKY. GIVEN
THE ABUNDANCE OF MID LEVEL DRY AIR...AND STRONG 850MB WINDS AROUND 45
KNOTS...WE COULD SEE THE POTENTIAL FOR SOME HIGHER WINDS TO GET MIXED
DOWN WITH THE SHOWERS. HOWEVER...EVEN WITHOUT THE CONVECTIVE SUPPORT
FOR WINDS...THE SYNOPTIC SETUP BEHIND THE FRONT SHOULD SUPPORT 40+
MPH WINDS...ESPECIALLY ACROSS THE NORTHERN HALF OF THE AREA.
THUS...WILL GO AHEAD WITH A WIND ADVISORY FOR THE NORTHERN HALF OF
THE AREA. CONDITIONS ARE MORE MARGINAL FARTHER SOUTH...BUT A WIND
ADVISORY FOR THE HIGH TERRAIN NEAR THE VIRGINIA BORDER ALSO SEEMS IN
ORDER GIVEN THE STRONG WINDS AT 850MB. BEST THREAT FOR THE HIGHER
WINDS WILL BE AFTER 17Z AND BEFORE 03Z TONIGHT.
CONDITIONS WILL QUITE DOWN SOME THIS EVENING AS SUBSIDENCE SPREADS IN
BEHIND THE DEPARTING FRONT. HOWEVER...A SHORTWAVE TROUGH WILL PUSH
EAST ACROSS THE AREA LATE TONIGHT...WITH THE MOISTURE DEPTH
INCREASING TO SUPPORT SOME LIGHT RAIN/DRIZZLE. COLDER AIR WILL ALSO
BE SPILLING INTO THE AREA TONIGHT BEHIND THE FRONT. WHILE MOST AREAS
WILL STAY MILD ENOUGH FOR JUST RAIN...THE HIGHER TERRAIN IN THE
SOUTHEAST WILL SUPPORT SOME SNOW CHANCES. IN FACT...CONDITIONS ALIGN
GOOD ENOUGH TONIGHT WE COULD SEE A LIGHT COATING OF SNOW ON THE HIGH
TERRAIN ABOVE 2500 FEET LATE TONIGHT.
HEIGHTS WILL BE QUICK TO BUILD BACK ACROSS THE AREA ON CHRISTMAS.
CLOUDS MAY BE STUBBORN THROUGH THE FIRST HALF OF THE DAY...BUT WE
SHOULD DEFINITELY SEE A DECREASING TREND THROUGH THE AFTERNOON AND
EVENING AS THE RIDGE CENTERS ITSELF OVER THE REGION. HIGHS WILL
STRUGGLE TO WARM GIVEN THE ABUNDANCE OF CLOUDS THROUGH THE FIRST HALF
OF THE DAY...SO PLAN TO KEEP HIGHS LIMITED TO THE LOW TO MID 40S WITH
30S ON THE HIGHER TERRAIN IN THE SOUTHEAST.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 420 AM EST WED DEC 24 2014
THE PERIOD IS EXPECTED TO BEGIN WITH A CLOSED UPPER LOW CONTINUING TO
DEPART TO THE NORTHEAST OF THE REGION WITH UPPER LEVEL RIDGING
BUILDING ACROSS THE AREA AT THE START OF THE PERIOD. FURTHER TO THE
WEST A TROUGH IS EXPECTED TO EXTEND FROM THE NORTHERN PLAINS SOUTH
INTO THE SOUTHERN ROCKIES AND NORTHERN MEXICO. SFC AND UPPER LEVEL
RIDGING WILL GRADUALLY WORK ACROSS THE AREA FOR THU NIGHT INTO FRIDAY
AND THEN DEPART TO THE EAST FRIDAY NIGHT INTO SATURDAY. MEANWHILE A
SHORTWAVE TROUGH IS ANTICIPATED TO EJECT FROM THE WESTERN TROUGH
ACROSS THE PLAINS TOWARD THE GREAT LAKES FROM FRIDAY INTO SATURDAY.
THIS WILL LEAD TO GRADUALLY LOWERING HEIGHTS ACROSS THE GREAT LAKES
AND OH VALLEY AND A COLD FRONT DROPPING TOWARD THE REGION TO START
THE WEEKEND. THIS SHOULD BEGIN THE START OF AN UNSETTLED PERIOD.
OVER TIME...A RATHER BROAD TROUGH IS EXPECTED TO DEVELOP FROM CENTRAL
CANADA SOUTH INTO THE ROCKIES AND THEN EAST INTO THE EASTERN CONUS.
MODELS VARY FROM RUN TO RUN AND MODEL TO MODEL WITH THE HANDLING OF
INDIVIDUAL SHORTWAVES IN WEST SOUTH TO SOUTHWEST FLOW DURING THIS
PERIOD AND THE INTERACTION WITH A BAROCLINIC ZONE...THE FRONT THAT
MOVES INTO THE AREA EARLY IN THE WEEKEND...RESULTING IN SFC WAVES
DEVELOPING ALONG THE FRONT. THE ECMWF IS GENERALLY SLOWER BRINGING
THIS FRONT ACROSS THE AREA AND IS ALSO STRONGER AND FURTHER SOUTHEAST
WITH A SFC WAVE SUN NIGHT INTO MONDAY. AS THIS LAST SYSTEM DEPARTS AN
ARCTIC BOUNDARY SHOULD APPROACH THE AREA TUE OR WED.
DUE TO AN OVERALL LACK OF COLDER AIR FOR MOST OF THE PERIOD...MUCH OF
THE PRECIPITATION SHOULD FALL AS RAIN...ALTHOUGH SOME SNOW MAY MIX IN
ON SUNDAY NIGHT INTO EARLY ON MONDAY IN THE HIGHEST TERRAIN AND NORTH
OF THE MTN PARKWAY. A MIX OF RAIN AND SNOW WILL REMAIN POSSIBLE INTO
THE DAY ON TUESDAY AS WE HELD ONTO SLIGHT CHANCE POPS TO ACCOUNT FOR
THE ECMWF RUN. BOTH THE GFS AND ECMWF RUNS SUPPORT A WET END TO THE
WEEKEND.
AS FOR TEMPERATURES...THE PATTERN FAVORS A RIDGE VALLEY TEMPERATURE
SPLIT ON THU NIGHT AS SKIES WILL HAVE CLEARED OR SHOULD BE CLEARING
AS SFC AND UPPER LEVEL RIDGING WORK INTO THE AREA. A RELATIVELY DRY
AIR MASS AND A DOWNSLOPE COMPONENT SHOULD LEAD TO A RATHER MILD DAY
ON FRIDAY...ESPECIALLY FOR VALLEYS NEAR THE VA BORDER. THE DEPARTING
RIDGE SHOULD AGAIN FAVOR MILDER LOWS ON FRI NIGHT...BUT YET ANOTHER
RIDGE/VALLEY SPLIT. SATURDAY SHOULD AGAIN BE MILD AHEAD OF THE
BOUNDARY. WITH THE BAROCLINIC ZONE OVER OR NEAR THE REGION A
GENERALLY NW TO SOUTH OR SOUTHEAST GRADIENT IN TEMPERATURES IS
ANTICIPATED FOR THE REMAINDER OF THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 648 AM EST WED DEC 24 2014
DRY AIR HAS INVADED THE AREA THANKS TO SOUTHEAST DOWNSLOPING FLOW OFF
THE HIGH TERRAIN. THIS HAS PUSHED CEILINGS UP TO OVER 10KFT. THIS
SHOULD REMAIN THE CASE THIS MORNING. COLD FRONT WILL BRING LOWER CIGS
LATER THIS AFTERNOON AND EVENING...EVENTUALLY REACHING MVFR LATE THIS
AFTERNOON. SOME SHOWERS WILL STILL BE POSSIBLE AS THE FRONT CROSSES
THE AREA. THE BIGGER STORY WILL BE THE POTENTIAL FOR STRONG GUSTY
WINDS AS THE FRONT BLOWS ACROSS HERE TODAY. WIND GUSTS UP TO 40 KNOTS
WILL BE POSSIBLE WITH THE HIGHEST READINGS EXPECTED ACROSS NORTHERN
KENTUCKY. WINDS WILL SLOWLY SUBSIDE THIS EVENING...BUT SHOULD REMAIN
SOMEWHAT GUSTY THROUGH THE NIGHT. A CHANCE OF RAIN WILL RETURN LATE
TONIGHT AS DEEPER MOISTURE SPREADS ACROSS THE AREA.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 10 PM EST THIS EVENING FOR KYZ044-050>052-
058>060-068-069-088-104-106>120.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...KAS
LONG TERM...JP
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
648 AM EST WED DEC 24 2014
.UPDATE...
ISSUED AT 648 AM EST WED DEC 24 2014
UPDATED TO LOWER POPS THIS MORNING AS SOUTHEAST FLOW CONTINUES TO
STRENGTHEN WITH CLOUD HEIGHTS CONTINUING TO GO UP. THEY ARE NOW OVER
10KFT. THUS...CHANCES FOR MEASURABLE RAIN ARE DECREASING THROUGH THE
MORNING HOURS. BEST CHANCE OF RAIN STILL LOOKS TO COME WITH THE COLD
FRONT AS IT CROSSES THE AREA THIS AFTERNOON. LATEST HI-RES MODELS
CONTINUE TO SHOW THE POSSIBILITY OF A FEW THUNDERSTORMS AS THE FRONT
PUSHES ACROSS OUR AREA. SHOULD WARM UP NICELY GIVEN THE SOUTHEAST
FLOW AND LIMITED LOW CEILINGS THIS MORNING. WOULDN`T BE SURPRISED TO
SEE US GET EVEN WARMER THAN THE FORECAST CURRENTLY REFLECTS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 316 AM EST WED DEC 24 2014
AREA OF LOW PRESSURE IS NOW STARTING TO MAKE ITS MOVE NORTH ACROSS
CENTRAL KENTUCKY...AND WILL END UP OVER SOUTHEAST MICHIGAN BY THIS
EVENING. STRONG LIFT ASSOCIATED WITH THE LOW PRESSURE SYSTEM WILL
SPREAD ACROSS THE AREA THROUGH DAYBREAK WITH RAIN BECOMING WIDESPREAD
ONCE AGAIN AFTER A BRIEF LULL OVER THE PAST FEW HOURS. HRRR AND RAP
ARE IN GOOD AGREEMENT THAT THIS LIFT WILL EXIT TO THE NORTH BY 9 OR
10 AM...WITH ANOTHER LULL IN PRECIPITATION EXPECTED THROUGH MIDDAY.
WITH THE MIDDAY LULL IN PRECIPITATION...HIGHS WILL WARM INTO THE 60S
FOR ONE MORE DAY.
FINALLY AS THE LOW SHIFTS NORTH THOUGH...A STRONG COLD FRONT WILL
PUSH EAST ACROSS THE AREA THIS AFTERNOON. WITH THE MILD
TEMPERATURES...WE MAY GENERATE SOME WEAK INSTABILITY TO SUPPORT
CONVECTIVE SHOWERS DEVELOPING ALONG THE FRONT AS IT PUSHES ACROSS THE
AREA. WHILE THUNDER CHANCES REMAIN LOW...CANNOT RULE OUT SOME THUNDER
WITH THE STRONGER CELLS...ESPECIALLY ACROSS NORTHERN KENTUCKY. GIVEN
THE ABUNDANCE OF MID LEVEL DRY AIR...AND STRONG 850MB WINDS AROUND 45
KNOTS...WE COULD SEE THE POTENTIAL FOR SOME HIGHER WINDS TO GET MIXED
DOWN WITH THE SHOWERS. HOWEVER...EVEN WITHOUT THE CONVECTIVE SUPPORT
FOR WINDS...THE SYNOPTIC SETUP BEHIND THE FRONT SHOULD SUPPORT 40+
MPH WINDS...ESPECIALLY ACROSS THE NORTHERN HALF OF THE AREA.
THUS...WILL GO AHEAD WITH A WIND ADVISORY FOR THE NORTHERN HALF OF
THE AREA. CONDITIONS ARE MORE MARGINAL FARTHER SOUTH...BUT A WIND
ADVISORY FOR THE HIGH TERRAIN NEAR THE VIRGINIA BORDER ALSO SEEMS IN
ORDER GIVEN THE STRONG WINDS AT 850MB. BEST THREAT FOR THE HIGHER
WINDS WILL BE AFTER 17Z AND BEFORE 03Z TONIGHT.
CONDITIONS WILL QUITE DOWN SOME THIS EVENING AS SUBSIDENCE SPREADS IN
BEHIND THE DEPARTING FRONT. HOWEVER...A SHORTWAVE TROUGH WILL PUSH
EAST ACROSS THE AREA LATE TONIGHT...WITH THE MOISTURE DEPTH
INCREASING TO SUPPORT SOME LIGHT RAIN/DRIZZLE. COLDER AIR WILL ALSO
BE SPILLING INTO THE AREA TONIGHT BEHIND THE FRONT. WHILE MOST AREAS
WILL STAY MILD ENOUGH FOR JUST RAIN...THE HIGHER TERRAIN IN THE
SOUTHEAST WILL SUPPORT SOME SNOW CHANCES. IN FACT...CONDITIONS ALIGN
GOOD ENOUGH TONIGHT WE COULD SEE A LIGHT COATING OF SNOW ON THE HIGH
TERRAIN ABOVE 2500 FEET LATE TONIGHT.
HEIGHTS WILL BE QUICK TO BUILD BACK ACROSS THE AREA ON CHRISTMAS.
CLOUDS MAY BE STUBBORN THROUGH THE FIRST HALF OF THE DAY...BUT WE
SHOULD DEFINITELY SEE A DECREASING TREND THROUGH THE AFTERNOON AND
EVENING AS THE RIDGE CENTERS ITSELF OVER THE REGION. HIGHS WILL
STRUGGLE TO WARM GIVEN THE ABUNDANCE OF CLOUDS THROUGH THE FIRST HALF
OF THE DAY...SO PLAN TO KEEP HIGHS LIMITED TO THE LOW TO MID 40S WITH
30S ON THE HIGHER TERRAIN IN THE SOUTHEAST.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 420 AM EST WED DEC 24 2014
THE PERIOD IS EXPECTED TO BEGIN WITH A CLOSED UPPER LOW CONTINUING TO
DEPART TO THE NORTHEAST OF THE REGION WITH UPPER LEVEL RIDGING
BUILDING ACROSS THE AREA AT THE START OF THE PERIOD. FURTHER TO THE
WEST A TROUGH IS EXPECTED TO EXTEND FROM THE NORTHERN PLAINS SOUTH
INTO THE SOUTHERN ROCKIES AND NORTHERN MEXICO. SFC AND UPPER LEVEL
RIDGING WILL GRADUALLY WORK ACROSS THE AREA FOR THU NIGHT INTO FRIDAY
AND THEN DEPART TO THE EAST FRIDAY NIGHT INTO SATURDAY. MEANWHILE A
SHORTWAVE TROUGH IS ANTICIPATED TO EJECT FROM THE WESTERN TROUGH
ACROSS THE PLAINS TOWARD THE GREAT LAKES FROM FRIDAY INTO SATURDAY.
THIS WILL LEAD TO GRADUALLY LOWERING HEIGHTS ACROSS THE GREAT LAKES
AND OH VALLEY AND A COLD FRONT DROPPING TOWARD THE REGION TO START
THE WEEKEND. THIS SHOULD BEGIN THE START OF AN UNSETTLED PERIOD.
OVER TIME...A RATHER BROAD TROUGH IS EXPECTED TO DEVELOP FROM CENTRAL
CANADA SOUTH INTO THE ROCKIES AND THEN EAST INTO THE EASTERN CONUS.
MODELS VARY FROM RUN TO RUN AND MODEL TO MODEL WITH THE HANDLING OF
INDIVIDUAL SHORTWAVES IN WEST SOUTH TO SOUTHWEST FLOW DURING THIS
PERIOD AND THE INTERACTION WITH A BAROCLINIC ZONE...THE FRONT THAT
MOVES INTO THE AREA EARLY IN THE WEEKEND...RESULTING IN SFC WAVES
DEVELOPING ALONG THE FRONT. THE ECMWF IS GENERALLY SLOWER BRINGING
THIS FRONT ACROSS THE AREA AND IS ALSO STRONGER AND FURTHER SOUTHEAST
WITH A SFC WAVE SUN NIGHT INTO MONDAY. AS THIS LAST SYSTEM DEPARTS AN
ARCTIC BOUNDARY SHOULD APPROACH THE AREA TUE OR WED.
DUE TO AN OVERALL LACK OF COLDER AIR FOR MOST OF THE PERIOD...MUCH OF
THE PRECIPITATION SHOULD FALL AS RAIN...ALTHOUGH SOME SNOW MAY MIX IN
ON SUNDAY NIGHT INTO EARLY ON MONDAY IN THE HIGHEST TERRAIN AND NORTH
OF THE MTN PARKWAY. A MIX OF RAIN AND SNOW WILL REMAIN POSSIBLE INTO
THE DAY ON TUESDAY AS WE HELD ONTO SLIGHT CHANCE POPS TO ACCOUNT FOR
THE ECMWF RUN. BOTH THE GFS AND ECMWF RUNS SUPPORT A WET END TO THE
WEEKEND.
AS FOR TEMPERATURES...THE PATTERN FAVORS A RIDGE VALLEY TEMPERATURE
SPLIT ON THU NIGHT AS SKIES WILL HAVE CLEARED OR SHOULD BE CLEARING
AS SFC AND UPPER LEVEL RIDGING WORK INTO THE AREA. A RELATIVELY DRY
AIRMASS AND A DOWNSLOPE COMPONENT SHOULD LEAD TO A RATHER MILD DAY ON
FRIDAY...ESPECIALLY FOR VALLEYS NEAR THE VA BORDER. THE DEPARTING
RIDGE SHOULD AGAIN FAVOR MILDER LOWS ON FRI NIGHT...BUT YET ANOTHER
RIDGE/VALLEY SPLIT. SATURDAY SHOULD AGAIN BE MILD AHEAD OF THE
BOUNDARY. WITH THE BAROCLINIC ZONE OVER OR NEAR THE REGION A GENERALLY
NW TO SOUTH OR SOUTHEAST GRADIENT IN TEMPERATURES IS ANTICIPATED FOR
THE REMAINDER OF THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 648 AM EST WED DEC 24 2014
DRY AIR HAS INVADED THE AREA THANKS TO SOUTHEAST DOWNSLOPING FLOW OFF
THE HIGH TERRAIN. THIS HAS PUSHED CEILINGS UP TO OVER 10KFT. THIS
SHOULD REMAIN THE CASE THIS MORNING. COLD FRONT WILL BRING LOWER CIGS
LATER THIS AFTERNOON AND EVENING...EVENTUALLY REACHING MVFR LATE THIS
AFTERNOON. SOME SHOWERS WILL STILL BE POSSIBLE AS THE FRONT CROSSES
THE AREA. THE BIGGER STORY WILL BE THE POTENTIAL FOR STRONG GUSTY
WINDS AS THE FRONT BLOWS ACROSS HERE TODAY. WIND GUSTS UP TO 40 KNOTS
WILL BE POSSIBLE WITH THE HIGHEST READINGS EXPECTED ACROSS NORTHERN
KENTUCKY. WINDS WILL SLOWLY SUBSIDE THIS EVENING...BUT SHOULD REMAIN
SOMEWHAT GUSTY THROUGH THE NIGHT. A CHANCE OF RAIN WILL RETURN LATE
TONIGHT AS DEEPER MOISTURE SPREADS ACROSS THE AREA.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM NOON TODAY TO 10 PM EST THIS EVENING FOR
KYZ044-050>052-058>060-068-069-088-104-106>112-114-118>120.
&&
$$
UPDATE...KAS
SHORT TERM...KAS
LONG TERM...JP
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
454 AM EST WED DEC 24 2014
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 316 AM EST WED DEC 24 2014
AREA OF LOW PRESSURE IS NOW STARTING TO MAKE ITS MOVE NORTH ACROSS
CENTRAL KENTUCKY...AND WILL END UP OVER SOUTHEAST MICHIGAN BY THIS
EVENING. STRONG LIFT ASSOCIATED WITH THE LOW PRESSURE SYSTEM WILL
SPREAD ACROSS THE AREA THROUGH DAYBREAK WITH RAIN BECOMING WIDESPREAD
ONCE AGAIN AFTER A BRIEF LULL OVER THE PAST FEW HOURS. HRRR AND RAP
ARE IN GOOD AGREEMENT THAT THIS LIFT WILL EXIT TO THE NORTH BY 9 OR
10 AM...WITH ANOTHER LULL IN PRECIPITATION EXPECTED THROUGH MIDDAY.
WITH THE MIDDAY LULL IN PRECIPITATION...HIGHS WILL WARM INTO THE 60S
FOR ONE MORE DAY.
FINALLY AS THE LOW SHIFTS NORTH THOUGH...A STRONG COLD FRONT WILL
PUSH EAST ACROSS THE AREA THIS AFTERNOON. WITH THE MILD
TEMPERATURES...WE MAY GENERATE SOME WEAK INSTABILITY TO SUPPORT
CONVECTIVE SHOWERS DEVELOPING ALONG THE FRONT AS IT PUSHES ACROSS THE
AREA. WHILE THUNDER CHANCES REMAIN LOW...CANNOT RULE OUT SOME THUNDER
WITH THE STRONGER CELLS...ESPECIALLY ACROSS NORTHERN KENTUCKY. GIVEN
THE ABUNDANCE OF MID LEVEL DRY AIR...AND STRONG 850MB WINDS AROUND 45
KNOTS...WE COULD SEE THE POTENTIAL FOR SOME HIGHER WINDS TO GET MIXED
DOWN WITH THE SHOWERS. HOWEVER...EVEN WITHOUT THE CONVECTIVE SUPPORT
FOR WINDS...THE SYNOPTIC SETUP BEHIND THE FRONT SHOULD SUPPORT 40+
MPH WINDS...ESPECIALLY ACROSS THE NORTHERN HALF OF THE AREA.
THUS...WILL GO AHEAD WITH A WIND ADVISORY FOR THE NORTHERN HALF OF
THE AREA. CONDITIONS ARE MORE MARGINAL FARTHER SOUTH...BUT A WIND
ADVISORY FOR THE HIGH TERRAIN NEAR THE VIRGINIA BORDER ALSO SEEMS IN
ORDER GIVEN THE STRONG WINDS AT 850MB. BEST THREAT FOR THE HIGHER
WINDS WILL BE AFTER 17Z AND BEFORE 03Z TONIGHT.
CONDITIONS WILL QUITE DOWN SOME THIS EVENING AS SUBSIDENCE SPREADS IN
BEHIND THE DEPARTING FRONT. HOWEVER...A SHORTWAVE TROUGH WILL PUSH
EAST ACROSS THE AREA LATE TONIGHT...WITH THE MOISTURE DEPTH
INCREASING TO SUPPORT SOME LIGHT RAIN/DRIZZLE. COLDER AIR WILL ALSO
BE SPILLING INTO THE AREA TONIGHT BEHIND THE FRONT. WHILE MOST AREAS
WILL STAY MILD ENOUGH FOR JUST RAIN...THE HIGHER TERRAIN IN THE
SOUTHEAST WILL SUPPORT SOME SNOW CHANCES. IN FACT...CONDITIONS ALIGN
GOOD ENOUGH TONIGHT WE COULD SEE A LIGHT COATING OF SNOW ON THE HIGH
TERRAIN ABOVE 2500 FEET LATE TONIGHT.
HEIGHTS WILL BE QUICK TO BUILD BACK ACROSS THE AREA ON CHRISTMAS.
CLOUDS MAY BE STUBBORN THROUGH THE FIRST HALF OF THE DAY...BUT WE
SHOULD DEFINITELY SEE A DECREASING TREND THROUGH THE AFTERNOON AND
EVENING AS THE RIDGE CENTERS ITSELF OVER THE REGION. HIGHS WILL
STRUGGLE TO WARM GIVEN THE ABUNDANCE OF CLOUDS THROUGH THE FIRST HALF
OF THE DAY...SO PLAN TO KEEP HIGHS LIMITED TO THE LOW TO MID 40S WITH
30S ON THE HIGHER TERRAIN IN THE SOUTHEAST.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 420 AM EST WED DEC 24 2014
THE PERIOD IS EXPECTED TO BEGIN WITH A CLOSED UPPER LOW CONTINUING TO
DEPART TO THE NORTHEAST OF THE REGION WITH UPPER LEVEL RIDGING
BUILDING ACROSS THE AREA AT THE START OF THE PERIOD. FURTHER TO THE
WEST A TROUGH IS EXPECTED TO EXTEND FROM THE NORTHERN PLAINS SOUTH
INTO THE SOUTHERN ROCKIES AND NORTHERN MEXICO. SFC AND UPPER LEVEL
RIDGING WILL GRADUALLY WORK ACROSS THE AREA FOR THU NIGHT INTO FRIDAY
AND THEN DEPART TO THE EAST FRIDAY NIGHT INTO SATURDAY. MEANWHILE A
SHORTWAVE TROUGH IS ANTICIPATED TO EJECT FROM THE WESTERN TROUGH
ACROSS THE PLAINS TOWARD THE GREAT LAKES FROM FRIDAY INTO SATURDAY.
THIS WILL LEAD TO GRADUALLY LOWERING HEIGHTS ACROSS THE GREAT LAKES
AND OH VALLEY AND A COLD FRONT DROPPING TOWARD THE REGION TO START
THE WEEKEND. THIS SHOULD BEGIN THE START OF AN UNSETTLED PERIOD.
OVER TIME...A RATHER BROAD TROUGH IS EXPECTED TO DEVELOP FROM CENTRAL
CANADA SOUTH INTO THE ROCKIES AND THEN EAST INTO THE EASTERN CONUS.
MODELS VARY FROM RUN TO RUN AND MODEL TO MODEL WITH THE HANDLING OF
INDIVIDUAL SHORTWAVES IN WEST SOUTH TO SOUTHWEST FLOW DURING THIS
PERIOD AND THE INTERACTION WITH A BAROCLINIC ZONE...THE FRONT THAT
MOVES INTO THE AREA EARLY IN THE WEEKEND...RESULTING IN SFC WAVES
DEVELOPING ALONG THE FRONT. THE ECMWF IS GENERALLY SLOWER BRINGING
THIS FRONT ACROSS THE AREA AND IS ALSO STRONGER AND FURTHER SOUTHEAST
WITH A SFC WAVE SUN NIGHT INTO MONDAY. AS THIS LAST SYSTEM DEPARTS AN
ARCTIC BOUNDARY SHOULD APPROACH THE AREA TUE OR WED.
DUE TO AN OVERALL LACK OF COLDER AIR FOR MOST OF THE PERIOD...MUCH OF
THE PRECIPITATION SHOULD FALL AS RAIN...ALTHOUGH SOME SNOW MAY MIX IN
ON SUNDAY NIGHT INTO EARLY ON MONDAY IN THE HIGHEST TERRAIN AND NORTH
OF THE MTN PARKWAY. A MIX OF RAIN AND SNOW WILL REMAIN POSSIBLE INTO
THE DAY ON TUESDAY AS WE HELD ONTO SLIGHT CHANCE POPS TO ACCOUNT FOR
THE ECMWF RUN. BOTH THE GFS AND ECMWF RUNS SUPPORT A WET END TO THE
WEEKEND.
AS FOR TEMPERATURES...THE PATTERN FAVORS A RIDGE VALLEY TEMPERATURE
SPLIT ON THU NIGHT AS SKIES WILL HAVE CLEARED OR SHOULD BE CLEARING
AS SFC AND UPPER LEVEL RIDGING WORK INTO THE AREA. A RELATIVELY DRY
AIRMASS AND A DOWNSLOPE COMPONENT SHOULD LEAD TO A RATHER MILD DAY ON
FRIDAY...ESPECIALLY FOR VALLEYS NEAR THE VA BORDER. THE DEPARTING
RIDGE SHOULD AGAIN FAVOR MILDER LOWS ON FRI NIGHT...BUT YET ANOTHER
RIDGE/VALLEY SPLIT. SATURDAY SHOULD AGAIN BE MILD AHEAD OF THE
BOUNDARY. WITH THE BAROCLINIC ZONE OVER OR NEAR THE REGION A GENERALLY
NW TO SOUTH OR SOUTHEAST GRADIENT IN TEMPERATURES IS ANTICIPATED FOR
THE REMAINDER OF THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 228 AM EST WED DEC 24 2014
MVFR CIGS HAVE DISSIPATED OVERNIGHT AS DOWNSLOPING FLOW HAS TAKEN
OVER IN THE PRESENT WEAKLY FORCED ENVIRONMENT. ONE MORE ROUND OF
SHOWERS WILL PUSH NORTH LATE TONIGHT INTO THE MORNING HOURS AND MAY
BRING SOME MVFR CIGS AND VISIBILITIES. HOWEVER...AGAIN THIS SHOULD
NOT BE PERSISTENT. A COLD FRONT WILL THEN SURGE EAST ACROSS THE AREA
THIS AFTERNOON AND EVENING...WITH A PERIOD OF GUSTY SOUTHWEST WINDS
ANTICIPATED. THIS MAY ALSO BRING A FEW SHOWERS WITH IT. IN THE WAKE
OF THE FRONT...CIGS SHOULD LOWER BACK TO MVFR AND CONTINUE INTO
TONIGHT...POSSIBLY BORDERING ON IFR CONDITIONS AT TIMES. AFTER A LULL
IN PRECIPITATION INTO THE LATE EVENING HOURS...RAIN WILL REDEVELOP
LATE TONIGHT...WITH SOME SNOW POSSIBLY MIXING IN ABOVE 2500 FEET.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM NOON TODAY TO 10 PM EST THIS EVENING FOR
KYZ044-050>052-058>060-068-069-088-104-106>112-114-118>120.
&&
$$
SHORT TERM...KAS
LONG TERM...JP
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
316 AM EST WED DEC 24 2014
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 316 AM EST WED DEC 24 2014
AREA OF LOW PRESSURE IS NOW STARTING TO MAKE ITS MOVE NORTH ACROSS
CENTRAL KENTUCKY...AND WILL END UP OVER SOUTHEAST MICHIGAN BY THIS
EVENING. STRONG LIFT ASSOCIATED WITH THE LOW PRESSURE SYSTEM WILL
SPREAD ACROSS THE AREA THROUGH DAYBREAK WITH RAIN BECOMING WIDESPREAD
ONCE AGAIN AFTER A BRIEF LULL OVER THE PAST FEW HOURS. HRRR AND RAP
ARE IN GOOD AGREEMENT THAT THIS LIFT WILL EXIT TO THE NORTH BY 9 OR
10 AM...WITH ANOTHER LULL IN PRECIPITATION EXPECTED THROUGH MIDDAY.
WITH THE MIDDAY LULL IN PRECIPITATION...HIGHS WILL WARM INTO THE 60S
FOR ONE MORE DAY.
FINALLY AS THE LOW SHIFTS NORTH THOUGH...A STRONG COLD FRONT WILL
PUSH EAST ACROSS THE AREA THIS AFTERNOON. WITH THE MILD
TEMPERATURES...WE MAY GENERATE SOME WEAK INSTABILITY TO SUPPORT
CONVECTIVE SHOWERS DEVELOPING ALONG THE FRONT AS IT PUSHES ACROSS THE
AREA. WHILE THUNDER CHANCES REMAIN LOW...CANNOT RULE OUT SOME THUNDER
WITH THE STRONGER CELLS...ESPECIALLY ACROSS NORTHERN KENTUCKY. GIVEN
THE ABUNDANCE OF MID LEVEL DRY AIR...AND STRONG 850MB WINDS AROUND 45
KNOTS...WE COULD SEE THE POTENTIAL FOR SOME HIGHER WINDS TO GET MIXED
DOWN WITH THE SHOWERS. HOWEVER...EVEN WITHOUT THE CONVECTIVE SUPPORT
FOR WINDS...THE SYNOPTIC SETUP BEHIND THE FRONT SHOULD SUPPORT 40+
MPH WINDS...ESPECIALLY ACROSS THE NORTHERN HALF OF THE AREA.
THUS...WILL GO AHEAD WITH A WIND ADVISORY FOR THE NORTHERN HALF OF
THE AREA. CONDITIONS ARE MORE MARGINAL FARTHER SOUTH...BUT A WIND
ADVISORY FOR THE HIGH TERRAIN NEAR THE VIRGINIA BORDER ALSO SEEMS IN
ORDER GIVEN THE STRONG WINDS AT 850MB. BEST THREAT FOR THE HIGHER
WINDS WILL BE AFTER 17Z AND BEFORE 03Z TONIGHT.
CONDITIONS WILL QUITE DOWN SOME THIS EVENING AS SUBSIDENCE SPREADS IN
BEHIND THE DEPARTING FRONT. HOWEVER...A SHORTWAVE TROUGH WILL PUSH
EAST ACROSS THE AREA LATE TONIGHT...WITH THE MOISTURE DEPTH
INCREASING TO SUPPORT SOME LIGHT RAIN/DRIZZLE. COLDER AIR WILL ALSO
BE SPILLING INTO THE AREA TONIGHT BEHIND THE FRONT. WHILE MOST AREAS
WILL STAY MILD ENOUGH FOR JUST RAIN...THE HIGHER TERRAIN IN THE
SOUTHEAST WILL SUPPORT SOME SNOW CHANCES. IN FACT...CONDITIONS ALIGN
GOOD ENOUGH TONIGHT WE COULD SEE A LIGHT COATING OF SNOW ON THE HIGH
TERRAIN ABOVE 2500 FEET LATE TONIGHT.
HEIGHTS WILL BE QUICK TO BUILD BACK ACROSS THE AREA ON CHRISTMAS.
CLOUDS MAY BE STUBBORN THROUGH THE FIRST HALF OF THE DAY...BUT WE
SHOULD DEFINITELY SEE A DECREASING TREND THROUGH THE AFTERNOON AND
EVENING AS THE RIDGE CENTERS ITSELF OVER THE REGION. HIGHS WILL
STRUGGLE TO WARM GIVEN THE ABUNDANCE OF CLOUDS THROUGH THE FIRST HALF
OF THE DAY...SO PLAN TO KEEP HIGHS LIMITED TO THE LOW TO MID 40S WITH
30S ON THE HIGHER TERRAIN IN THE SOUTHEAST.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 316 AM EST WED DEC 24 2014
LONG TERM DISCUSSION WILL FOLLOW SHORTLY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 228 AM EST WED DEC 24 2014
MVFR CIGS HAVE DISSIPATED OVERNIGHT AS DOWNSLOPING FLOW HAS TAKEN
OVER IN THE PRESENT WEAKLY FORCED ENVIRONMENT. ONE MORE ROUND OF
SHOWERS WILL PUSH NORTH LATE TONIGHT INTO THE MORNING HOURS AND MAY
BRING SOME MVFR CIGS AND VISIBILITIES. HOWEVER...AGAIN THIS SHOULD
NOT BE PERSISTENT. A COLD FRONT WILL THEN SURGE EAST ACROSS THE AREA
THIS AFTERNOON AND EVENING...WITH A PERIOD OF GUSTY SOUTHWEST WINDS
ANTICIPATED. THIS MAY ALSO BRING A FEW SHOWERS WITH IT. IN THE WAKE
OF THE FRONT...CIGS SHOULD LOWER BACK TO MVFR AND CONTINUE INTO
TONIGHT...POSSIBLY BORDERING ON IFR CONDITIONS AT TIMES. AFTER A LULL
IN PRECIPITATION INTO THE LATE EVENING HOURS...RAIN WILL REDEVELOP
LATE TONIGHT...WITH SOME SNOW POSSIBLY MIXING IN ABOVE 2500 FEET.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM NOON TODAY TO 10 PM EST THIS EVENING FOR
KYZ044-050>052-058>060-068-069-088-104-106>112-114-118>120.
&&
$$
SHORT TERM...KAS
LONG TERM...JP
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
228 AM EST WED DEC 24 2014
.UPDATE...
ISSUED AT 228 AM EST WED DEC 24 2014
UPDATED TO REFINE POPS THROUGH THE REMAINDER OF THE NIGHT. IT LOOKS
LIKE ONE MORE BETTER SURGE OF MOISTURE WILL PUSH ACROSS THE AREA
STARTING FROM THE SOUTH AROUND 10Z...THEN PUSH NORTHWARD THROUGH THE
EARLY MORNING HOURS. THIS TIME AROUND IT SHOULD NOT PERSIST AS LONG
AND WE MAY ACTUALLY SEE A PRETTY GOOD BREAK FROM PRECIPITATION BY MID
MORNING...BEFORE THE COLD FRONT PUSHES EAST ACROSS THE AREA IN THE
AFTERNOON...BRINGING THE THREAT OF SCATTERED SHOWERS BACK TO THE
AREA.
UPDATE ISSUED AT 1116 PM EST TUE DEC 23 2014
LIGHTNING IN OUR AREA ENDED EARLY IN THE EVENING...WITH CONVECTIVE
SYSTEMS DOMINATING OVER THE DEEP SOUTH. THE NAM IS SUGGESTING A
RESURGENCE OF INSTABILITY MOVING IN FROM THE SW ON WEDNESDAY MORNING
AS LOW PRESSURE MOVES NORTH THROUGH CENTRAL KY AND ITS TRAILING COLD
FRONT APPROACHES. HAVE REMOVED THUNDER FOR TONIGHT...BUT KEPT A
POTENTIAL ON WEDNESDAY AHEAD OF THE FRONT.
UPDATE ISSUED AT 618 PM EST TUE DEC 23 2014
WIDESPREAD PRECIP HAS OCCURRED MOST OF THE FORECAST AREA...WITH THE
EXCEPTION OF THE FAR EAST. RAIN WILL CONTINUE AND SHOULD EVENTUALLY
AFFECT EVEN THE EASTERN PART OF THE AREA TONIGHT. PREVIOUS FORECAST
OF CATEGORICAL POPS STILL LOOKS ON TRACK. HAVE UPDATED TEMPS BASED ON
LATEST OBS AND MODEL DATA...BUT OVERALL THE CHANGES WERE MINIMAL.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 353 PM EST TUE DEC 23 2014
THIS AFTERNOON SHOWERS AND THUNDERSTORMS ARE SPREADING ACROSS
PORTIONS OF EASTERN KY. WSR-88D SHOWING BEST CONCENTRATION OF SHOWERS
AND THUNDERSTORMS GENERALLY ALONG AND JUST EAST OF THE WESTERN CWA
BORDER. SHOWERS HAVE BEEN MOVING NE ALONG THIS AREA WITH SOME AREAS
SEEING AROUND A QUARTER OF A INCH WITH HIGHER AMTS POSSIBLE IN
HEAVIER STORMS. HRRR GUIDANCE SEEMS TO HAVE A DECENT HANDLE ON THESE
BANDS OF SHOWERS AND THUNDERSTORMS AND HAS THESE BANDS ACROSS
PORTIONS OF THE TN VALLEY PROGRESSING NORTH ACROSS EASTERN KY THIS
EVENING INTO TONIGHT. 18Z SURFACE ANALYSIS SHOWS LOW PRESSURE
CONTINUING TO DEVELOP ALONG THE LA COAST LINE THIS AFTERNOON. THIS
AREA OF LOW PRESSURE IS EXPECTED TO CONTINUE TO MOVE NORTH AND EAST
OVERNIGHT INTO WEDNESDAY. THIS WILL CONTINUE TO SPREAD RAIN ACROSS
THE REGION. THIS SURFACE LOW WILL ALSO BRING A STRONG COLD FRONT
ACROSS EASTERN KY TOMORROW AFTERNOON THIS WILL PROVIDE GOOD LIFTING
MECHANISM FOR SHOWERS AND THUNDERSTORMS WITH GUSTY WINDS POSSIBLE.
BEHIND THIS FRONT WOULD EXPECT THERE TO CONTINUE TO BE GUSTY WINDS
PARTICULARLY ACROSS THE HIGHER TERRAIN AND NW PORTIONS OF THE CWA.
MOVING INTO WEDNESDAY NIGHT LOW PRESSURE IS FORECAST TO MOVE NORTH
INTO THE GREAT LAKES REGION AND WE WILL QUICKLY GET INTO THE DRY
SLOT. THEREFORE MOISTURE DOES GET CUTOFF AND LOOKING AT FORECAST
SOUNDINGS THIS WOULD LEAD TO LITTLE IF ANY ICE ALOFT. DID OPT TO KEEP
A SLIGHT CHANCE OF RAIN MIXED WITH SNOW AND MAYBE SOME DRIZZLE ACROSS
THE HIGHER TERRAIN...HOWEVER CONFIDENCE IN ANY SNOW CONTINUES TO
DECREASE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 429 PM EST TUE DEC 23 2014
THE MODELS ARE GENERALLY IN GOOD AGREEMENT WITH AN AMPLIFIED LONG
WAVE PATTERN TO CONTINUE THROUGH THE PERIOD ACROSS THE CONUS. MODEL
DIFFERENCES CONTINUE HOWEVER TOWARDS THE LATTER HALF OF THE
PERIOD...AND HAVE SIDED MORE WITH THE ECMWF/CANADIAN SOLUTION GIVEN
THE OVERALL BETTER CONTINUITY.
DEEPER TROUGHING WILL BE MOVING OFF TO THE EAST ON THURSDAY...WITH
ANY LIGHT PRECIPITATION COMING TO AN END ACROSS EASTERN KENTUCKY BY
THE MORNING HOURS. DRY WEATHER WILL RETURN FROM THURSDAY AFTERNOON
THROUGH EARLY SATURDAY MORNING...AS RIDGING TAKES HOLD ACROSS THE
OHIO AND TENNESSEE VALLEYS. MEANWHILE...TROUGHING WILL BE REASSERT
ITSELF ACROSS THE ROCKIES...WITH A COLD FRONT MOVING INTO THE AREA
FOR THE WEEKEND.
THE GFS REMAINS PROGRESSIVE WITH THIS BOUNDARY...WHILE THE
ECMWF/CANADIAN ARE SLOWER AND ALLOW FOR MORE SOUTHERN STREAM
INTERACTION...PROLONGING THE PRECIPITATION CHANCES ALL THE WAY INTO
EARLY NEXT WEEK. AGAIN...AM INCLINED TO LEAN TOWARDS THE
ECMWF/CANADIAN SOLUTION AS THE GFS HAS TRENDED MORE AMPLIFIED WITH
THE UPPER LEVEL PATTERN FROM 24 HOURS AGO. AS SUCH...HAVE FOLLOWED
SUIT WITH THE GIVEN BLENDED GUIDANCE AND ALLOWED FOR LIKELY POPS
BY SUNDAY...AND THEN LOWER CHANCES INTO EARLY NEXT UNTIL SOME OF THE
DETAILS CAN BE IRONED OUT. THE FORECAST TEMPERATURE PROFILES SUPPORT
MORE RAIN THEN SNOW THROUGH WEEKEND...AND THEN PERHAPS A SNOWIER
FINISH AS WE HEAD INTO TUESDAY DEPENDING HOW MUCH COLDER AIR ACTUALLY
MAKES IT IN.
FOR TEMPERATURES...GENERALLY ABOVE NORMAL READINGS LOOK ON TAP
THROUGH THE WEEKEND...WITH NEAR TO COOLER THAN NORMAL VALUES BY EARLY
NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 228 AM EST WED DEC 24 2014
MVFR CIGS HAVE DISSIPATED OVERNIGHT AS DOWNSLOPING FLOW HAS TAKEN
OVER IN THE PRESENT WEAKLY FORCED ENVIRONMENT. ONE MORE ROUND OF
SHOWERS WILL PUSH NORTH LATE TONIGHT INTO THE MORNING HOURS AND MAY
BRING SOME MVFR CIGS AND VISIBILITIES. HOWEVER...AGAIN THIS SHOULD
NOT BE PERSISTENT. A COLD FRONT WILL THEN SURGE EAST ACROSS THE AREA
THIS AFTERNOON AND EVENING...WITH A PERIOD OF GUSTY SOUTHWEST WINDS
ANTICIPATED. THIS MAY ALSO BRING A FEW SHOWERS WITH IT. IN THE WAKE
OF THE FRONT...CIGS SHOULD LOWER BACK TO MVFR AND CONTINUE INTO
TONIGHT...POSSIBLY BORDERING ON IFR CONDITIONS AT TIMES. AFTER A LULL
IN PRECIPITATION INTO THE LATE EVENING HOURS...RAIN WILL REDEVELOP
LATE TONIGHT...WITH SOME SNOW POSSIBLY MIXING IN ABOVE 2500 FEET.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...DJ
LONG TERM...GEOGERIAN
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
1116 PM EST TUE DEC 23 2014
.UPDATE...
ISSUED AT 1116 PM EST TUE DEC 23 2014
LIGHTNING IN OUR AREA ENDED EARLY IN THE EVENING...WITH CONVECTIVE
SYSTEMS DOMINATING OVER THE DEEP SOUTH. THE NAM IS SUGGESTING A
RESURGENCE OF INSTABILITY MOVING IN FROM THE SW ON WEDNESDAY MORNING
AS LOW PRESSURE MOVES NORTH THROUGH CENTRAL KY AND ITS TRAILING COLD
FRONT APPROACHES. HAVE REMOVED THUNDER FOR TONIGHT...BUT KEPT A
POTENTIAL ON WEDNESDAY AHEAD OF THE FRONT.
UPDATE ISSUED AT 618 PM EST TUE DEC 23 2014
WIDESPREAD PRECIP HAS OCCURRED MOST OF THE FORECAST AREA...WITH THE
EXCEPTION OF THE FAR EAST. RAIN WILL CONTINUE AND SHOULD EVENTUALLY
AFFECT EVEN THE EASTERN PART OF THE AREA TONIGHT. PREVIOUS FORECAST
OF CATEGORICAL POPS STILL LOOKS ON TRACK. HAVE UPDATED TEMPS BASED ON
LATEST OBS AND MODEL DATA...BUT OVERALL THE CHANGES WERE MINIMAL.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 353 PM EST TUE DEC 23 2014
THIS AFTERNOON SHOWERS AND THUNDERSTORMS ARE SPREADING ACROSS
PORTIONS OF EASTERN KY. WSR-88D SHOWING BEST CONCENTRATION OF SHOWERS
AND THUNDERSTORMS GENERALLY ALONG AND JUST EAST OF THE WESTERN CWA
BORDER. SHOWERS HAVE BEEN MOVING NE ALONG THIS AREA WITH SOME AREAS
SEEING AROUND A QUARTER OF A INCH WITH HIGHER AMTS POSSIBLE IN
HEAVIER STORMS. HRRR GUIDANCE SEEMS TO HAVE A DECENT HANDLE ON THESE
BANDS OF SHOWERS AND THUNDERSTORMS AND HAS THESE BANDS ACROSS
PORTIONS OF THE TN VALLEY PROGRESSING NORTH ACROSS EASTERN KY THIS
EVENING INTO TONIGHT. 18Z SURFACE ANALYSIS SHOWS LOW PRESSURE
CONTINUING TO DEVELOP ALONG THE LA COAST LINE THIS AFTERNOON. THIS
AREA OF LOW PRESSURE IS EXPECTED TO CONTINUE TO MOVE NORTH AND EAST
OVERNIGHT INTO WEDNESDAY. THIS WILL CONTINUE TO SPREAD RAIN ACROSS
THE REGION. THIS SURFACE LOW WILL ALSO BRING A STRONG COLD FRONT
ACROSS EASTERN KY TOMORROW AFTERNOON THIS WILL PROVIDE GOOD LIFTING
MECHANISM FOR SHOWERS AND THUNDERSTORMS WITH GUSTY WINDS POSSIBLE.
BEHIND THIS FRONT WOULD EXPECT THERE TO CONTINUE TO BE GUSTY WINDS
PARTICULARLY ACROSS THE HIGHER TERRAIN AND NW PORTIONS OF THE CWA.
MOVING INTO WEDNESDAY NIGHT LOW PRESSURE IS FORECAST TO MOVE NORTH
INTO THE GREAT LAKES REGION AND WE WILL QUICKLY GET INTO THE DRY
SLOT. THEREFORE MOISTURE DOES GET CUTOFF AND LOOKING AT FORECAST
SOUNDINGS THIS WOULD LEAD TO LITTLE IF ANY ICE ALOFT. DID OPT TO KEEP
A SLIGHT CHANCE OF RAIN MIXED WITH SNOW AND MAYBE SOME DRIZZLE ACROSS
THE HIGHER TERRAIN...HOWEVER CONFIDENCE IN ANY SNOW CONTINUES TO
DECREASE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 429 PM EST TUE DEC 23 2014
THE MODELS ARE GENERALLY IN GOOD AGREEMENT WITH AN AMPLIFIED LONG
WAVE PATTERN TO CONTINUE THROUGH THE PERIOD ACROSS THE CONUS. MODEL
DIFFERENCES CONTINUE HOWEVER TOWARDS THE LATTER HALF OF THE
PERIOD...AND HAVE SIDED MORE WITH THE ECMWF/CANADIAN SOLUTION GIVEN
THE OVERALL BETTER CONTINUITY.
DEEPER TROUGHING WILL BE MOVING OFF TO THE EAST ON THURSDAY...WITH
ANY LIGHT PRECIPITATION COMING TO AN END ACROSS EASTERN KENTUCKY BY
THE MORNING HOURS. DRY WEATHER WILL RETURN FROM THURSDAY AFTERNOON
THROUGH EARLY SATURDAY MORNING...AS RIDGING TAKES HOLD ACROSS THE
OHIO AND TENNESSEE VALLEYS. MEANWHILE...TROUGHING WILL BE REASSERT
ITSELF ACROSS THE ROCKIES...WITH A COLD FRONT MOVING INTO THE AREA
FOR THE WEEKEND.
THE GFS REMAINS PROGRESSIVE WITH THIS BOUNDARY...WHILE THE
ECMWF/CANADIAN ARE SLOWER AND ALLOW FOR MORE SOUTHERN STREAM
INTERACTION...PROLONGING THE PRECIPITATION CHANCES ALL THE WAY INTO
EARLY NEXT WEEK. AGAIN...AM INCLINED TO LEAN TOWARDS THE
ECMWF/CANADIAN SOLUTION AS THE GFS HAS TRENDED MORE AMPLIFIED WITH
THE UPPER LEVEL PATTERN FROM 24 HOURS AGO. AS SUCH...HAVE FOLLOWED
SUIT WITH THE GIVEN BLENDED GUIDANCE AND ALLOWED FOR LIKELY POPS
BY SUNDAY...AND THEN LOWER CHANCES INTO EARLY NEXT UNTIL SOME OF THE
DETAILS CAN BE IRONED OUT. THE FORECAST TEMPERATURE PROFILES SUPPORT
MORE RAIN THEN SNOW THROUGH WEEKEND...AND THEN PERHAPS A SNOWIER
FINISH AS WE HEAD INTO TUESDAY DEPENDING HOW MUCH COLDER AIR ACTUALLY
MAKES IT IN.
FOR TEMPERATURES...GENERALLY ABOVE NORMAL READINGS LOOK ON TAP
THROUGH THE WEEKEND...WITH NEAR TO COOLER THAN NORMAL VALUES BY EARLY
NEXT WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 813 PM EST TUE DEC 23 2014
ALTHOUGH RAIN WAS FALLING AT MOST LOCATIONS...CONDITIONS WERE MAINLY
VFR OVER ALL BUT THE SW AND FAR WESTERN PORTIONS OF THE JKL FORECAST
AREA AT THE START OF THE PERIOD...WITH DOWNSLOPE FLOW FROM THE SOUTH
SOUTHEAST HELPING TO MITIGATE LOW CLOUDS AND FOG. MVFR VISIBILITY WAS
COMMON FROM MIDDLESBORO AND LONDON WESTWARD. ALTHOUGH SOME
FLUCTUATIONS CAN BE EXPECTED TONIGHT...THIS GENERAL SCENARIO SHOULD
CONTINUE. DURING THE DAY ON WEDNESDAY A COLD FRONT WILL MOVE IN FROM
THE WEST AND BRING A POTENTIAL INCREASE IN SHOWER INTENSITY BEFORE IT
PASSES...WITH A RISK OF THUNDERSTORMS TOO. AS THE FRONT PASSES...
WINDS WILL VEER TOWARD THE SW AND THE DOWNSLOPE COMPONENT WILL BE
LOST. AS THIS HAPPENS...CEILINGS SHOULD DROP TO MVFR AND IFR.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...DJ
LONG TERM...GEOGERIAN
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
259 PM EST WED DEC 24 2014
.SYNOPSIS...
STRONG LOW PRESSURE AND ITS ASSOCIATED COLD FRONT WILL CROSS THE
REGION TODAY INTO TONIGHT BRINGING SHOWERS...A FEW THUNDERSTORMS...
AND STRONG WINDS THIS EVENING.
&&
.NEAR TERM /THROUGH TONIGHT/...
EARLIER REMOVAL OF POPS DUE TO LACK OF FORCING WITHIN THE QUASI-WARM
SECTOR (EXCEPT FOR THE PA/WV/MD RIDGES) HAS PLAYED OUT WELL WITH
NOTHING MORE THAN A FEW SPITS. THIS TREND SHOULD CONTINUE FOR THE
NEXT SEVERAL HOURS WITH JUST A FEW BRIEF SHOWERS ACROSS MOST OF THE
CWA...AND STEADIER RAINS ACROSS THE LAUREL HIGHLANDS AND POINTS
SOUTH.
MEANWHILE...A DEEPENING AND INCREASINGLY NEGATIVE TILT MID LEVEL
TROUGH WAS BEGINNING TO ACCELERATE NORTHEAST THROUGH ILLINOIS THIS
AFTERNOON. LARGE SCALE ASCENT...ASSOCIATED WITH STRONG MID LEVEL
HEIGHT FALLS...WAS BEGINNING TO OVERTAKE THE WARM SECTOR...AND
CONFIRMED BY VISIBLE SATELLITE IMAGERY WITH A RECENT INCREASE IN
SW-NE ORIENTED LOW-TOPPED CONVECTIVE BANDS. THIS FORCED ASCENT IS
OCCURRING WEST OF THE PRONOUNCED MID-HIGH LEVEL MOIST PLUME WHICH
HAS ENVELOPED THE REGION...AND THUS ITS EVOLUTION OVER THE NEXT
SEVERAL HOURS IS AN INTERESTING FORECAST CHALLENGE.
DYNAMICALLY FORCED CONVECTION...MOST OF WHICH WILL BE ALONG AND POST
SFC FRONTAL...WILL REACH THE WESTERN CWA AROUND 22Z AND EXIT THE
EASTERN RIDGES AROUND 05Z. AN AXIS OF MODEST INSTABILITY...ON THE
ORDER OF 100-200 J/KG MUCAPE...WILL GRADUALLY SHIFT NORTHEAST ACROSS
THE ENTIRE CWA THIS EVENING...EVEN WITH THE LOSS OF DAYLIGHT. IN
FACT...AREAS OF NW PA AND THE LAUREL HIGHLANDS...WHICH HAVE BEEN
EITHER NORTH OF THE WARM FRONT OR EAST OF THE DAMMING WEDGE
FRONT...WILL LIKELY SEE A SPIKE IN TEMPERATURES/DEWPOINTS EARLY THIS
EVENING AS A PRE-FRONTAL TROUGH EFFECTIVELY SCOURS THE AREA AND
SHIFTS WINDS INTO THE SOUTHWEST. PRECIPITATION LOOKS TO BE NEARLY
CERTAIN...SO THE QUESTION PRIMARILY FOCUSES ON THUNDER
CHANCES. GIVEN THE MID LEVEL SUBSIDENCE WITHIN THE SYNOPTIC DRY
SLOT...SURFACE BASED CONVECTIVE CLOUD TOPS WILL LIKELY BE LIMITED TO
AROUND 16-18KFT PER SOUNDING ANALYSIS...MAKING LIGHTNING GENERATION
DIFFICULT BUT CERTAINLY NOT IMPOSSIBLE. HAVE RETAINED "ISOLATED
THUNDER" WORDING FOR EARLY THIS EVENING.
REGARDING THE WIND ADVISORY...THE WINDOW FOR STRONG GUSTS IS MUCH
SMALLER THAN THE EXISTING ADVISORY WOULD SUGGEST...OWING TO A
NATURALLY POOR THERMAL CONTRAST ASSOCIATED WITH PROGRESSIVE NEGATIVE
TILT TROUGHS. IN THE ABSENCE OF STRONG COLD ADVECTION AND A SIZABLE
POST-FRONTAL SURFACE HIGH...THE STRONG LOW LEVEL PRESSURE GRADIENT
WILL BE CO-LOCATED BENEATH THE MID LEVEL JET AXIS...WHICH ITSELF
WILL MOVE SWIFTLY THROUGH THE AREA. THIS LIMITS THE WINDOW OF
OPPORTUNITY FOR STRONG WIND GUSTS TO FRONTAL CONVECTION AND ONLY A
FEW HOURS BEHIND THE FRONT. THE EXCEPTION WILL BE OVER THE SOUTHEAST
RIDGES WHERE THE EFFECTS OF STRONGER WINDS ALOFT WILL LINGER
OVERNIGHT. DOWNWARD MOMENTUM TRANSPORT FROM PRECIPITATION WILL
LIKELY YIELD MOST OF THE STRONGER GUSTS...NORTHEAST CELL MOVEMENT
(PARALLEL TO MID LEVEL FLOW VECTORS) WOULD SUGGEST THAT STRONGER
CONVECTIVE CELLS COULD YIELD SOME RATHER IMPRESSIVE GUSTS. GIVEN THE
STRONG LINEAR FORCING UNDERWAY...WOULD NOT BE SURPRISED TO SEE A
NARROW COLD-FRONTAL SQUALL LINE DEVELOP OVER OHIO/KENTUCKY OVER THE
NEXT SEVERAL HOURS. DESPITE THE SPARSE LIGHTNING YIELD EXPECTED...
ANY SHORT-FUSE THREAT FOR DAMAGING WINDS WOULD BE HANDLED BY SEVERE
THUNDERSTORM WARNINGS.
WIND ADVISORY IS IN THE PROCESS OF BEING MODIFIED AS FOLLOWS:
OH/WV PANHANDLE: 22-04Z
PA/WV (EXCEPT THE RIDGES): 00Z-06Z
PA/WV/MD RIDGES: 03Z-09Z
OTHERWISE...LARGE SCALE ASCENT ENDS QUICKLY FROM WEST TO EAST AFTER
06Z...AND ALTHOUGH A CHANGE-OVER FROM RAIN TO SNOW IS
DEPICTED...ONLY FLURRIES OR EVEN DRIZZLE ARE ANTICIPATED.
BOOKBINDER
&&
.SHORT TERM /CHRISTMAS DAY INTO CHRISTMAS NIGHT/...
SOUTHWEST WINDS WILL DIMINISH QUICKLY TOMORROW MORNING...AND A
ONE-SHOT DAY OF COLD AIR WILL ARRIVE WITH TEMPERATURES STRUGGLING TO
GET BACK TO 40 DEGREES UNDER CLOUD SKIES. ENOUGH RESIDUAL LIFT
AROUND THE DEPARTING CYCLONE WILL PERSIST IN THE MORNING TO GENERATE
SOME SCATTERED SNOW SHOWERS...ALTHOUGH THE MOISTURE DEPTH IS SO
SHALLOW THAT IT MAY AGAIN BE MORE OF A DRIZZLE/SNIZZLE. DO NOT
ANTICIPATE MORE THAN A LIGHT DUSTING UP TOWARD/NORTH OF I-80. ACROSS
THE RIDGES...A STRONGER UPSLOPE WIND COMPONENT IS DEPICTED BY THE
MODELS SO PERHAPS A SPARSE INCH COULD FALL ACROSS THE MD/WV RIDGES.
BOOKBINDER
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
AS IS TYPICAL WITH PROGRESSIVE NEGATIVE TILT TROUGHS...THE BRIEF
SHOT OF COLD AIR WILL DEPART AS THE SYSTEM LIFTS INTO THE CANADIAN
MARITIMES...ALLOWING FOR A TEMPORARY RETURN TO ZONAL AND/OR DAMPENED
MID LEVEL RIDGING OVER THE EASTERN CONUS FRIDAY AND
SATURDAY...FEATURING MUCH ABOVE NORMAL TEMPERATURES.
A PROGRESSIVE WAVE WILL SETTLE ACROSS THE AREA SATURDAY NIGHT AND
EARLY SUNDAY BRINGING A CHANCE FOR PRECIPITATION...AND BETTER ACCESS
TO MORE SEASONABLY COLD AIR IN ITS WAKE.
BOOKBINDER
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
WITH THE FORECAST AREA STILL MOSTLY IN THE WARM SECTOR...VFR
CONDITIONS TO START FOR MOST TERMINALS. WITH THE EASTERN RIDGES ON
THE FRINGE OF CONTINUED DAMMING...LOWER CLOUDS AND EVEN SOME FOG
LINGER THERE. LLWS GROUPS INCLUDED AS SSW WINDS OF 40-50 LIE JUST
A COUPLE THOUSAND FEET OFF THE SURFACE.
WELL-ADVERTISED COLD FRONT WILL PUSH THROUGH DURING THE EVENING
HOURS BETWEEN 22Z AND 04Z. BAND OF LOW-TOPPED CONVECTION STILL
BEING FORECAST BY HRRR AND OTHER MODELS AND HAVE HANDLED THIS WITH
TWO HOUR TEMPO GROUPS IN EACH TAF. CIGS WILL DROP BACK TO MVFR AS
THE FRONT APPROACHES AND PASSES. MAIN ISSUE WILL BE THE
WIND...WITH S/SW GUSTS TO 40-45 KNOTS POSSIBLE WITH
CONVECTION..AND IMMEDIATELY FOLLOWING FROPA. WINDS WILL SLOWLY
DIMINISH WITH TIME OVERNIGHT BUT STILL EXPECT AT LEAST 20-30 KNOT
GUSTS THROUGH THE REMAINDER OF THE TAF PERIOD. MVFR CIGS WILL
CONTINUE...PERHAPS LOWERING TO IFR BY 12Z CLOSER TO LAKE ERIE.
LINGERING PRECIP WILL CHANGE OVER TO SNOW SHOWERS BY 12Z
AREAWIDE...BUT SIGNIFICANT RESTRICTIONS FROM SNOW ARE NOT FORECAST.
OUTLOOK.../WEDNESDAY NIGHT THROUGH MONDAY/...
CIG/VIS RESTRICTIONS THROUGH THURSDAY WILL IMPROVE TO VFR FRIDAY
AND CONTINUE UNTIL ANOTHER FRONTAL SYSTEM CROSSES THE REGION
SATURDAY AFTERNOON.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WIND ADVISORY FROM 9 PM THIS EVENING TO 4 AM EST THURSDAY
FOR MDZ001.
OH...WIND ADVISORY UNTIL 11 PM EST THIS EVENING FOR OHZ039>041-
048>050-057>059-068-069.
PA...WIND ADVISORY FROM 7 PM THIS EVENING TO 1 AM EST THURSDAY FOR
PAZ007>009-013>016-020>023-029-031-073-075.
WIND ADVISORY FROM 9 PM THIS EVENING TO 4 AM EST THURSDAY FOR
PAZ074-076.
WV...WIND ADVISORY UNTIL 11 PM EST THIS EVENING FOR WVZ001>004-012.
WIND ADVISORY FROM 7 PM THIS EVENING TO 1 AM EST THURSDAY FOR
WVZ021-022.
WIND ADVISORY FROM 9 PM THIS EVENING TO 4 AM EST THURSDAY FOR
WVZ023-041.
&&
$$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
223 PM EST WED DEC 24 2014
.SYNOPSIS...
LOW PRESSURE STRENGTHENS WEST OF THE MOUNTAINS TODAY...AND . AN
ASSOCIATED COLD FRONT WILL CROSS THE AREA TONIGHT. HIGH PRESSURE
BUILDS BACK IN FROM THE SOUTHWEST CHRISTMAS DAY THROUGH FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
LATEST WX ANALYSIS CONTINUES TO FEATURE A DYNAMIC SYSTEM
TAKING SHAPE OVER THE DEEP SOUTH INTO THE TENNESSEE VALLEY AT
MIDDAY. LOCALLY...A RESIDUAL COOL-WEDGE AIRMASS IS HANGING TOUGH
ACROSS THE PIEDMONT, KEEPING TEMPS IN THE MID/UPPER 40S TO LOW 50S
ALONG AND W OF THE RIC METRO AREA. MEANWHILE, SFC WARM/COASTAL
FRONT IS MOVING ONSHORE WITH TEMPERATURES NOW WELL INTO THE
60S OVER SE VA & NE NC. WV SAT IMAGERY SHOWING BROAD SWATH OF WARM
CONVEYOR BELT MOISTURE LIFTING NORTH FROM THE EAST CENTRAL GULF
COAST ACROSS THE LOCAL AREA.
SFC LOW OVER THE SE CONUS WILL DEEPEN AND TRACK NNE INTO THE OHIO
VALLEY THROUGH THIS EVENING. BROAD SWATH OF MOISTURE WILL LIFT ENE
ACROSS THE REGION THROUGH THE BALANCE OF THE DAY, WITH PERIODIC
SHOWERS CONTINUING OVER THE PIEDMONT. THE NEW NAM/ARW IS A BIT
CLOSER IN HRRR DEPICTION OF BRIEF LULL IN PCPN BY LATE AFTN ON
INTO THE EARLY EVENING AS MID-LEVEL DRY SLOT, CURRENTLY LIFTING
ACROSS THE MID SOUTH INTO THE WESTERN CAROLINAS, SWINGS ACROSS
THE REGION. HOWEVER, PLENTY OF LLVL MOISTURE TO KEEP OVC WORDING
THROUGHOUT.
REGARDING CONVECTIVE POTENTIAL, HAVE CONFINED THUNDER WORDING TO
THE SE COASTAL PLAIN AFTER 20Z AS TEMPERATURES AND DEWPOINTS
CONTINUE TO RISE. SPC HAS ADDED THE SE IN A SLIGHT SEVERE RISK FOR
TONIGHT IN THE PRESENCE OF A WARM AND MOISTURE RICH AIRMASS AND A
STRONG 925-700MB WIND FIELD. DESPITE MEAGER SFC BASED INSTABILITY
WITH LACK OF CLOUD COVER, MID LVL SHEAR/HELICITY PARAMETERS WOULD
ARGUE FOR A CONTINUED THUNDER MENTION OVER THE COASTAL AREAS.
THUS, WL RETAIN SLIGHT CHC T OVER THE COASTAL PLAIN, MAINLY FOR
THE LATE AFTN AND EVENING HOURS.
THE COLD FRONT ARRIVES FROM THE W LATE THIS EVENING AND MOVES W-E
ACROSS THE AREA BETWEEN 03-06Z TONIGHT. DROPPED POPS OFF DURING
AFOREMENTIONED LULL PERIOD EARLY THIS EVENING, WITH MORE SCATTERED
RAIN SHRAS TO PERSIST LATER IN THE EVENING AND AFTER
MIDNIGHT...RAPIDLY DIMINISHING BEHIND THE FRONT AFTER 06Z TOWARDS
DAWN CHRISTMAS MORNING.
BY LATE AFTERNOON, EXPECT TEMPS TO RANGE FROM THE LOW TO MID 50S
WELL INLAND...MID/UPPER 60S FOR CENTRAL PORTIONS TO AROUND 70 SE.
THESE HIGHS WILL BE NEAR DAILY RECORDS...SEE THE CLIMATE SECTION
BELOW FOR DETAILS. GIVEN ONLY WEAK CAA, EXPECT TEMPS TO BE SLOW TO
DROP OFF OVERNIGHT, LIKELY LINGERING IN THE 50S AND 60S FOR MUCH
OF THE NIGHT.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
DRIER AIR ARRIVES CHRISTMAS MORNING AS HIGH PRESSURE BUILDS IN FROM
THE W. A SLOWER FRONTAL PASSAGE WILL RESULT IN A MILD CHRISTMAS
MORNING WITH LOWS RANGING FROM THE MID 40S FAR W...TO THE MID/UPPER
50S SE. THE SKY SHOULD BECOME MAINLY SUNNY WITH SCT AFTERNOON CU
ALONG WITH BREEZY WESTERLY FLOW BY MID/LATE MORNING CHRISTMAS DAY.
HIGHS SHOULD RANGE FROM THE MID 50S TO LOWER 60S CHRISTMAS DAY AS
CAA IS WEAK AND WILL BE OFFSET BY DOWNSLOPE WARMING (AND DUE TO A
WARM BEGINNING).
CLEAR/SEASONABLE THURSDAY NIGHT WITH LOWS IN THE UPPER 20S TO MID
30S. SURFACE HIGH PRESSURE SETTLES IMMEDIATELY OFF THE COAST FRIDAY
RESULTING IN LIMITED MIXING/LIGHT WINDS AND SUNNY CONDITIONS. HIGHS
SHOULD GENERALLY BE IN THE 50S.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE MODELS ARE IN GOOD AGREEMENT TO BEGIN THE PERIOD FRIDAY NIGHT
WITH THE STRONG RIDGING OVER THE SOUTHEASTERN US AND HIGH PRESSURE
OVER THE SOUTHEAST...CENTERED OVER EASTERN VA/NC. BUT THE MODELS
STRUGGLE WITH THE BREAKING DOWN OF THE RIDGE WITH THE GFS BREAKING
IT DOWN MUCH MORE QUICKLY THAN THE ECMWF. THE GFS ALLOW THE NEXT
COLD FRONT TO DROP INTO THE ARE SAT NIGHT AND MOVES IT SOUTH OF
THE REGION BY SUNDAY MORNING...SETTING UP AN OVERRUNNING PATTERN
SUNDAY AFTERNOON INTO MONDAY MORNING. THE ECMWF...AND THE 12Z IS
FURTHER NORTH WITH FEATURES THAN 00Z RUN...KEEPS THE RIDGE MUCH
STRONGER OVER THE SE AND DOES NOT ALLOW THE COLD FRONT TO MOVE
THROUGH THE AREA SAT NIGHT. IT STALLS THE FRONT OVER THE AREA ON
SUNDAY AND AS A WAVE OF LOW PRESSURE FORMS ALONG THE BOUNDARY AND
LIFTS NE INTO THE CENTRAL APPALACHIANS...IT PUSHES GULF MOISTURE
INTO THE AREA. THE 00Z ECMWF PUSHED THE WAVE OFF THE COAST BY
MONDAY...BUT THE 12Z RUN LIFTS THE LOW TO THE NORTH AND DRAGS A
COLD FRONT ACROSS THE REGION ON TUESDAY.
SO FOR NOW WITH THE GREAT SPREAD IN THE MODELS...HAVE TRENDED
TOWARD HPC/WPC GUIDANCE...WHICH IS SIMILAR TO THE 00Z ECMWF AND
BROUGHT THE WAVE INTO THE REGION ON SUNDAY AFTERNOON AND EVENING
WITH IT EXITING BY MONDAY AFTERNOON. HAVE INCREASED POPS TO 50%
FOR THAT PERIOD...KEEPING SATURDAY DRY. HAVE ALSO GONE DRY ON
MONDAY NIGHT INTO TUESDAY. THE BIG DIFFERENCE COMES TO
TEMPERATURES AS THE GFS WOULD ALLOW MUCH COLD AIR INTO THE REGION
BEGINNING ON SUNDAY THROUGH TUESDAY. THIS COULD ALSO POTENTIALLY
LEAD TO SOME WINTRY PCPN WITH WAVE ON SUNDAY NIGHT. FOR NOW HAVE
KEPT TEMPERATURES ABOVE FREEZING AND ALL RAIN WITH THE COLD AIR
BEING KEPT MORE TO THE NORTH. FOR TEMPERATURES HAVE ALLOW FOR A
GRADUAL COOL DOWN THROUGH THE PERIOD WITH THE COLDEST AIR ARRIVING
ON TUESDAY WITH HIGHS IN THE 40S.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
COMPLEX WEATHER SYSTEM ACROSS THE REGION THIS AFTERNOON AS WARM FRONTAL
BOUNDARY AS MOVED INTO THE AREA FROM THE EAST...STRETCHING FROM
NEAR DOV SW TO JUST NORTH OF XSA TO NEAR RIC AND THEN SW TO RDU.
EAST OF THE FRONT...THE WINDS HAVE TURNED SOUTHERLY AND THE
CEILINGS ARE BOUNCING FROM LIFR IN SHOWERS TO VFR WITH
VISIBILITIES ONLY BEING REDUCED IN THE SHOWERS. WEST OF THE
FRONT...THE LOW LIFR CLOUDS AND IFR TO LIFR VISIBILITIES LINGER.
THE FRONT.
THE LOW PRESSURE SYSTEM ASSOCIATED WITH THE FRONT WILL LIFT FROM
THE OHIO VALLEY NORTHEASTWARD INTO SERN CANADA AND PULL AN
ASSOCIATED COLD FRONT ACROSS THE REGION. THE WEDGE OF COOLER AIR
THAT IS WEST OF THE WARM FRONT AT THIS TIME WILL BE HARD TO
DISLODGE...BUT EVENTUALLY EXPECT THIS TO BREAK AND ALLOW CEILINGS
TO LIFT. SO FOR RIC DO SHOW SOME CEILING IMPROVEMENT LATER THIS
AFTERNOON AND EARLY THIS EVENING. THE REST OF THE SITES ARE ALL
EAST OF THE FRONT AND WHILE SOME IFR CEILINGS ARE STILL
AROUND...THE MAJORITY OF THE CEILINGS ARE MVFR OR HIGHER WITH THE
WIND BLOWING 10 TO 15 KT WITH HIGHER GUST.
THE COLD FRONT WILL ARRIVE THIS EVENING BETWEEN 3Z AND 9Z. AHEAD
OF THE FRONT ANOTHER LINE OF SHOWERS IS EXPECTED...ALTHOUGH WITH
THE DEEPER MOISTURE EAST OF THE AREA BY THEN IT MAY BE A SMALLER
NARROWER LINE. CURRENTLY ALLOWED FOR ABOUT 3 - 4 HOUR WINDOW OF
MVFR CONDITIONS WITH THE SHOWERS BUT IT MAY BE LESS THAN THAT.
BEHIND THE FRONT...THE AIR DRIES QUICKLY WITH VFR CONDITIONS
RETURNING BY 12Z FOR MOST AREAS.
OUTLOOK...HIGH PRESSURE DOMINATES THURSDAY AFTERNOON THROUGH
SATURDAY WITH DRY WEATHER. A CHC FOR RAIN RETURNS SUNDAY AS LOW
PRESSURE APPROACHES FROM THE WEST.
&&
.MARINE...
WINDS HAVE INCREASED TO 15 TO 20 KT OVER THE WATERS WITH THE WARM
FRONT LIFTING NORTH OF THE AREA. AS A RESULT...THE FOG THAT HAD
BEEN PLAGUING THE REGION HAS LIFTED AND THE ADVISORY HAS BEEN
CANCELLED.
PREV DISCUSSION....
DENSE FOG ADVISORY IS IN EFFECT FOR THE MARINE AREA THROUGH LATE
THIS AFTERNOON AS WARM MOIST AIR MOVES OVER THE RELATIVELY COOL
WATERS.
AS OF 11Z...WINDS WERE BEGINNING TO INCREASE FROM THE SE. SCA
STARTED AT 15Z FOR THE MOUTH OF THE BAY AS WAVES WILL SOON REACH 4
FT IN THE CHANNEL.
PREVIOUS DISCUSSION...
AS OF 08Z...WINDS REMAIN LIGHT OVER THE MARINE AREA BUT ARE FORECAST
TO INCREASE FROM THE SE AND THEN S THIS MORNING AS A WARM FRONT
MOVES N THROUGH THE WATERS AND LOW PRESSURE DEEPENS OVER THE OHIO
VALLEY. SCA IS IN EFFECT FOR ALL THE WATERS EXCEPT THE RIVERS SAVE
THE LOWER JAMES. SCA CONDITIONS OVER INLAND WATERS MAY BE MINIMAL
AT FIRST DUE TO LIMITED MIXING BUT WILL BECOME MORE FAVORABLE
THURSDAY MORNING. HAVE ADDED THE LOWER JAMES WITH TIMES STAGGERED
SLIGHTLY FROM THE BAY (STARTING AT 21Z TODAY AND ENDING 3 HOURS
EARLIER THURSDAY). LATER SHIFTS MAY NEED TO CONSIDER SCA BEHIND
THE COLD FRONT FOR OTHER RIVER ZONES ON THURSDAY MORNING.
SCA IS ALREADY IN EFFECT N OF PARRAMORE ISLAND. SEAS ARE EXPECTED TO
BUILD TO 5 FT OR HIGHER BY 18Z S OF THERE AND DECIDED TO BEGIN SCA S
OF PARRAMORE ISLAND AT 15Z TO ALLOW SUFFICIENT CUSHION.
HIGH PRESSURE THEN BUILDS INTO THE REGION ON THURSDAY NIGHT AND
LINGERS THROUGH SATURDAY AS A STRONG UPPER LEVEL RIDGE BUILDS INTO
THE SOUTHEASTERN US AND KEEPS STRONG HIGH PRESSURE AT THE SURFACE
OVER THE REGION THROUGH SATURDAY. LOW PRESSURE APPROACHES FROM THE
SW SUNDAY AND MOVES ACROSS THE REGION MONDAY. PRELIMINARY
INDICATIONS DO NOT INDICATE THAT A SCA WILL BE NEEDED WITH THIS
SYSTEM.
&&
.TIDES/COASTAL FLOODING...
WATER LEVELS AT BISHOPS HEAD AND CAMBRIDGE ARE EXPECTED TO
APPROACH MINOR FLOODING LATE TODAY AND EARLY THIS EVENING.
&&
.CLIMATE...
RECORD HIGHS FOR CHRISTMAS EVE/WED 12/24:
RICHMOND.......71 F (1988)
NORFOLK........75 F (1891)
SALISBURY......67 F (1990)
ELIZ CITY NC...75 F (1990)
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...COASTAL FLOOD ADVISORY UNTIL 8 PM EST THIS EVENING FOR
MDZ021>023.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST THURSDAY FOR ANZ630>634-
650-652-654-656-658.
SMALL CRAFT ADVISORY UNTIL 1 PM EST THURSDAY FOR ANZ638.
&&
$$
SYNOPSIS...AJZ/ALB
NEAR TERM...AJZ/MAM
SHORT TERM...AJZ/LKB
LONG TERM...ESS
AVIATION...ESS
MARINE...LSA/ESS
TIDES/COASTAL FLOODING...
CLIMATE...
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1246 PM EST WED DEC 24 2014
.SYNOPSIS...
STRONG LOW PRESSURE AND ITS ASSOCIATED COLD FRONT WILL CROSS THE
REGION TODAY INTO TONIGHT BRINGING SHOWERS AND STRONG WINDS.
&&
.NEAR TERM /THROUGH TONIGHT/...
NO CHANGES MADE THIS MORNING AS THE NEAR TERM LOOKS TO BE IN GOOD
SHAPE.
**NOTE** THERE WAS AN ERROR OVERNIGHT THAT RESULTED IN HIGH SNOW
AMOUNTS MAKING IT INTO THE FORECAST FOR TOMORROW MORNING. WE ARE
CURRENTLY WORKING ON THE ISSUE...BUT IN THE MEANTIME PLEASE
DISMISS HIGHER AMOUNTS. PREV DISCUSSION BELOW..
DEEPENING LOW PRES AND ITS ASSOCIATED CDFNT WL TRACK FM THE
OH VLY INTO THE GT LKS RGN TDA INTO TNGT. PERIODIC SHWRS WL CONT
TDA INTO TNGT AS MSTR STREAMS IN FM THE GULF IN SW FLOW AHD OF THE
ADVNG SYSTEM...AND AS FROPA OCCURS. AS COLD ADVCTN SETS UP A FEW
SNW SHWRS ARE PSBL OVRNGT. PROGRESSION AND A LACK OF SUSTAINED
CNVRGNC SHOULD LMT BASIN AVG RAIN TOTALS TO ARND A HALF INCH FOR
THE PD.
THE POTENTIAL FOR STRONG WINDS WITH PASSAGE OF...AND IMMEDIATELY
BEHIND THE CDFNT IS EXPD WED EVE INTO ERLY THU. IN ADDN...ELEVATED
INSTBY COULD RESULT IN A FEW TSTMS ALG THE CDFNT LT TDA AND THIS
EVE...SOME OF WHICH COULD MIX DOWN DAMAGING WNDS. THESE DAMAGING
WND GUSTS COULD BE HANDLED BY CNVCTV WRNGS IF THIS POTENTIAL
MATERIALIZES. UNTIL THEN...STRONG WARM ADVCTN WL CAP THE SFC
TDA...INHIBITING MIXING/GUSTS.
ISSUED A WND ADVY FOR GUSTS 45 TO 50 MPH ASSOCIATED WITH THE
SYNOPTIC PRES GRADIENT WNDS LT TDA INTO ERLY THU. THE ADVY MAY BE
AUGMENTED BY STORM PREDICTION CENTER PARTICIPATION IN A SHALLOW
CONVECTIVE EVENT AS MNTND ABV.
TEMPS ARE EXPD TO AVG ARND 20 TO 25 DEG ABV SEASONAL LVLS TDA.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
CONTD GUSTY WNDS ARE EXPD INTO ERLY THU ESP ESP ACRS WRN PA AND IN
THE RIDGES. WKNG PRES GRADIENT SHOULD ALLOW FOR DCRG WND GUSTS
THRU THE DAY. SNW SHWR CHCS ARE EXPD THU MRNG INTO ERLY AFTN WITH
AN ADVNG UPR TROF...THOUGH LACK OF DEEP MSTR AND MARGINAL TEMPS
SHOULD ALLOW FOR LTL IF ANY ACCUMS MAINLY N OF I 80 AND IN THE
RIDGES. BLDG HIGH PRES IS PROGGED TO BRING DRY WEA LTR THU INTO
FRI NGT. ANOTHER ADVNG GT LKS SHRTWV WL RTN RAIN SHWR CHCS SAT.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
SOUTHWESTERLY FLOW ALOFT WILL REMAIN IN PLACE THROUGH THE EXTENDED
AS SEVERAL SHORTWAVES DIVE SOUTH ACROSS THE INTERMOUNTAIN WEST AND
REINFORCE LONGWAVE TROUGHING. MODELS CONTINUE TO SHOW POOR
CONSENSUS IN HANDLING DETAILS...MAINLY WITH PLACEMENT RATHER THAN
TIME. A MORE BROADBRUSH WAS CONTINUED GIVE NT HIGH UNCERTAINTY BUT
IN GENERAL..FRONTAL SYSTEMS ARE PROGGED TO IMPACT THE REGION OVER
THE WEEKEND AND AGAIN LATE MONDAY / TUESDAY.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
WITH THE FORECAST AREA STILL MOSTLY IN THE WARM SECTOR...VFR
CONDITIONS TO START FOR MOST TERMINALS. WITH THE EASTERN RIDGES ON
THE FRINGE OF CONTINUED DAMMING...LOWER CLOUDS AND EVEN SOME FOG
LINGER THERE. LLWS GROUPS INCLUDED AS SSW WINDS OF 40-50 LIE JUST
A COUPLE THOUSAND FEET OFF THE SURFACE.
WELL-ADVERTISED COLD FRONT WILL PUSH THROUGH DURING THE EVENING
HOURS BETWEEN 22Z AND 04Z. BAND OF LOW-TOPPED CONVECTION STILL
BEING FORECAST BY HRRR AND OTHER MODELS AND HAVE HANDLED THIS WITH
TWO HOUR TEMPO GROUPS IN EACH TAF. CIGS WILL DROP BACK TO MVFR AS
THE FRONT APPROACHES AND PASSES. MAIN ISSUE WILL BE THE
WIND...WITH S/SW GUSTS TO 40-45 KNOTS POSSIBLE WITH
CONVECTION..AND IMMEDIATELY FOLLOWING FROPA. WINDS WILL SLOWLY
DIMINISH WITH TIME OVERNIGHT BUT STILL EXPECT AT LEAST 20-30 KNOT
GUSTS THROUGH THE REMAINDER OF THE TAF PERIOD. MVFR CIGS WILL
CONTINUE...PERHAPS LOWERING TO IFR BY 12Z CLOSER TO LAKE ERIE.
LINGERING PRECIP WILL CHANGE OVER TO SNOW SHOWERS BY 12Z
AREAWIDE...BUT SIGNIFICANT RESTRICTIONS FROM SNOW ARE NOT FORECAST.
OUTLOOK.../WEDNESDAY NIGHT THROUGH MONDAY/...
CIG/VIS RESTRICTIONS THROUGH THURSDAY WILL IMPROVE TO VFR FRIDAY
AND CONTINUE UNTIL ANOTHER FRONTAL SYSTEM CROSSES THE REGION
SATURDAY AFTERNOON.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WIND ADVISORY FROM 7 PM THIS EVENING TO 9 AM EST THURSDAY FOR
MDZ001.
DENSE FOG ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR MDZ001.
OH...WIND ADVISORY FROM 4 PM THIS AFTERNOON TO 4 AM EST THURSDAY
FOR OHZ039>041-048>050-057>059-068-069.
PA...WIND ADVISORY FROM 7 PM THIS EVENING TO 9 AM EST THURSDAY FOR
PAZ007>009-013>016-020>023-029-031-073>076.
WV...WIND ADVISORY FROM 4 PM THIS AFTERNOON TO 4 AM EST THURSDAY
FOR WVZ001>004-012.
WIND ADVISORY FROM 7 PM THIS EVENING TO 9 AM EST THURSDAY FOR
WVZ021>023-041.
DENSE FOG ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR WVZ023-
041.
&&
$$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1214 PM EST WED DEC 24 2014
.SYNOPSIS...
LOW PRESSURE STRENGTHENS WEST OF THE MOUNTAINS TODAY...AND . AN
ASSOCIATED COLD FRONT WILL CROSS THE AREA TONIGHT. HIGH PRESSURE
BUILDS BACK IN FROM THE SOUTHWEST CHRISTMAS DAY THROUGH FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
LATEST WX ANALYSIS CONTINUES TO FEATURE A DYNAMIC SYSTEM
TAKING SHAPE OVER THE DEEP SOUTH INTO THE TENNESSEE VALLEY AT
MIDDAY. LOCALLY...A RESIDUAL COOL-WEDGE AIRMASS IS HANGING TOUGH
ACROSS THE PIEDMONT, KEEPING TEMPS IN THE MID/UPPER 40S TO LOW 50S
ALONG AND W OF THE RIC METRO AREA. MEANWHILE, SFC WARM/COASTAL
FRONT IS MOVING ONSHORE WITH TEMPERATURES NOW WELL INTO THE
60S OVER SE VA & NE NC. WV SAT IMAGERY SHOWING BROAD SWATH OF WARM
CONVEYOR BELT MOISTURE LIFTING NORTH FROM THE EAST CENTRAL GULF
COAST ACROSS THE LOCAL AREA.
SFC LOW OVER THE SE CONUS WILL DEEPEN AND TRACK NNE INTO THE OHIO
VALLEY THROUGH THIS EVENING. BROAD SWATH OF MOISTURE WILL LIFT ENE
ACROSS THE REGION THROUGH THE BALANCE OF THE DAY, WITH PERIODIC
SHOWERS CONTINUING OVER THE PIEDMONT. THE NEW NAM/ARW IS A BIT
CLOSER IN HRRR DEPICTION OF BRIEF LULL IN PCPN BY LATE AFTN ON
INTO THE EARLY EVENING AS MID-LEVEL DRY SLOT, CURRENTLY LIFTING
ACROSS THE MID SOUTH INTO THE WESTERN CAROLINAS, SWINGS ACROSS
THE REGION. HOWEVER, PLENTY OF LLVL MOISTURE TO KEEP OVC WORDING
THROUGHOUT.
REGARDING CONVECTIVE POTENTIAL, HAVE CONFINED THUNDER WORDING TO
THE SE COASTAL PLAIN AFTER 20Z AS TEMPERATURES AND DEWPOINTS
CONTINUE TO RISE. SPC HAS ADDED THE SE IN A SLIGHT SEVERE RISK FOR
TONIGHT IN THE PRESENCE OF A WARM AND MOISTURE RICH AIRMASS AND A
STRONG 925-700MB WIND FIELD. DESPITE MEAGER SFC BASED INSTABILITY
WITH LACK OF CLOUD COVER, MID LVL SHEAR/HELICITY PARAMETERS WOULD
ARGUE FOR A CONTINUED THUNDER MENTION OVER THE COASTAL AREAS.
THUS, WL RETAIN SLIGHT CHC T OVER THE COASTAL PLAIN, MAINLY FOR
THE LATE AFTN AND EVENING HOURS.
THE COLD FRONT ARRIVES FROM THE W LATE THIS EVENING AND MOVES W-E
ACROSS THE AREA BETWEEN 03-06Z TONIGHT. DROPPED POPS OFF DURING
AFOREMENTIONED LULL PERIOD EARLY THIS EVENING, WITH MORE SCATTERED
RAIN SHRAS TO PERSIST LATER IN THE EVENING AND AFTER
MIDNIGHT...RAPIDLY DIMINISHING BEHIND THE FRONT AFTER 06Z TOWARDS
DAWN CHRISTMAS MORNING.
BY LATE AFTERNOON, EXPECT TEMPS TO RANGE FROM THE LOW TO MID 50S
WELL INLAND...MID/UPPER 60S FOR CENTRAL PORTIONS TO AROUND 70 SE.
THESE HIGHS WILL BE NEAR DAILY RECORDS...SEE THE CLIMATE SECTION
BELOW FOR DETAILS. GIVEN ONLY WEAK CAA, EXPECT TEMPS TO BE SLOW TO
DROP OFF OVERNIGHT, LIKELY LINGERING IN THE 50S AND 60S FOR MUCH
OF THE NIGHT.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
DRIER AIR ARRIVES CHRISTMAS MORNING AS HIGH PRESSURE BUILDS IN FROM
THE W. A SLOWER FRONTAL PASSAGE WILL RESULT IN A MILD CHRISTMAS
MORNING WITH LOWS RANGING FROM THE MID 40S FAR W...TO THE MID/UPPER
50S SE. THE SKY SHOULD BECOME MAINLY SUNNY WITH SCT AFTERNOON CU
ALONG WITH BREEZY WESTERLY FLOW BY MID/LATE MORNING CHRISTMAS DAY.
HIGHS SHOULD RANGE FROM THE MID 50S TO LOWER 60S CHRISTMAS DAY AS
CAA IS WEAK AND WILL BE OFFSET BY DOWNSLOPE WARMING (AND DUE TO A
WARM BEGINNING).
CLEAR/SEASONABLE THURSDAY NIGHT WITH LOWS IN THE UPPER 20S TO MID
30S. SURFACE HIGH PRESSURE SETTLES IMMEDIATELY OFF THE COAST FRIDAY
RESULTING IN LIMITED MIXING/LIGHT WINDS AND SUNNY CONDITIONS. HIGHS
SHOULD GENERALLY BE IN THE 50S.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE MODELS ARE IN GOOD AGREEMENT TO BEGIN THE PERIOD FRIDAY NIGHT
WITH THE STRONG RIDGING OVER THE SOUTHEASTERN US AND HIGH PRESSURE
OVER THE SOUTHEAST...CENTERED OVER EASTERN VA/NC. BUT THE MODELS
STRUGGLE WITH THE BREAKING DOWN OF THE RIDGE WITH THE GFS BREAKING
IT DOWN MUCH MORE QUICKLY THAN THE ECMWF. THE GFS ALLOW THE NEXT
COLD FRONT TO DROP INTO THE ARE SAT NIGHT AND MOVES IT SOUTH OF
THE REGION BY SUNDAY MORNING...SETTING UP AN OVERRUNNING PATTERN
SUNDAY AFTERNOON INTO MONDAY MORNING. THE ECMWF...AND THE 12Z IS
FURTHER NORTH WITH FEATURES THAN 00Z RUN...KEEPS THE RIDGE MUCH
STRONGER OVER THE SE AND DOES NOT ALLOW THE COLD FRONT TO MOVE
THROUGH THE AREA SAT NIGHT. IT STALLS THE FRONT OVER THE AREA ON
SUNDAY AND AS A WAVE OF LOW PRESSURE FORMS ALONG THE BOUNDARY AND
LIFTS NE INTO THE CENTRAL APPALACHIANS...IT PUSHES GULF MOISTURE
INTO THE AREA. THE 00Z ECMWF PUSHED THE WAVE OFF THE COAST BY
MONDAY...BUT THE 12Z RUN LIFTS THE LOW TO THE NORTH AND DRAGS A
COLD FRONT ACROSS THE REGION ON TUESDAY.
SO FOR NOW WITH THE GREAT SPREAD IN THE MODELS...HAVE TRENDED
TOWARD HPC/WPC GUIDANCE...WHICH IS SIMILAR TO THE 00Z ECMWF AND
BROUGHT THE WAVE INTO THE REGION ON SUNDAY AFTERNOON AND EVENING
WITH IT EXITING BY MONDAY AFTERNOON. HAVE INCREASED POPS TO 50%
FOR THAT PERIOD...KEEPING SATURDAY DRY. HAVE ALSO GONE DRY ON
MONDAY NIGHT INTO TUESDAY. THE BIG DIFFERENCE COMES TO
TEMPERATURES AS THE GFS WOULD ALLOW MUCH COLD AIR INTO THE REGION
BEGINNING ON SUNDAY THROUGH TUESDAY. THIS COULD ALSO POTENTIALLY
LEAD TO SOME WINTRY PCPN WITH WAVE ON SUNDAY NIGHT. FOR NOW HAVE
KEPT TEMPERATURES ABOVE FREEZING AND ALL RAIN WITH THE COLD AIR
BEING KEPT MORE TO THE NORTH. FOR TEMPERATURES HAVE ALLOW FOR A
GRADUAL COOL DOWN THROUGH THE PERIOD WITH THE COLDEST AIR ARRIVING
ON TUESDAY WITH HIGHS IN THE 40S.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 12Z...ANOTHER BAND OF RAIN WAS PROGRESSING INTO THE CWA FROM
THE SW. CIGS AND VSBYS WILL CONTINUE TO BE VARIABLE BUT ARE
EXPECTED TO BE PREDOMINANTLY IFR OR LOWER THIS MORNING. A BIT OF
IMPROVEMENT IS EXPECTED THIS AFTERNOON AS THE AREA BECOMES WARM
SECTORED BUT THE TAF SITES SHOULD BE MAINLY IFR IS STILL EXCEPT AT
ORF AND ECG. CONFIDENCE IN THE DEGREE OF IMPROVEMENT IS MARGINAL.
A COLD FRONT APPROACHES FROM THE WEST TONIGHT WITH SHOWERS AND A
SLGT CHC OF THUNDER (THIS PCPN NOT INCLUDED IN THE TAF).
CONDITIONS IMPROVE FROM THE WEST IN THE MORNING AS WINDS TURN TO
WESTERLY.
OUTLOOK...HIGH PRESSURE DOMINATES THURSDAY AFTERNOON THROUGH
SATURDAY WITH DRY WEATHER. A CHC FOR RAIN RETURNS SUNDAY AS LOW
PRESSURE APPROACHES FROM THE WEST.
&&
.MARINE...
DENSE FOG ADVISORY IS IN EFFECT FOR THE MARINE AREA THROUGH LATE
THIS AFTERNOON AS WARM MOIST AIR MOVES OVER THE RELATIVELY COOL
WATERS.
AS OF 11Z...WINDS WERE BEGINNING TO INCREASE FROM THE SE. SCA
STARTED AT 15Z FOR THE MOUTH OF THE BAY AS WAVES WILL SOON REACH 4
FT IN THE CHANNEL.
PREVIOUS DISCUSSION...
AS OF 08Z...WINDS REMAIN LIGHT OVER THE MARINE AREA BUT ARE FORECAST
TO INCREASE FROM THE SE AND THEN S THIS MORNING AS A WARM FRONT
MOVES N THROUGH THE WATERS AND LOW PRESSURE DEEPENS OVER THE OHIO
VALLEY. SCA IS IN EFFECT FOR ALL THE WATERS EXCEPT THE RIVERS SAVE
THE LOWER JAMES. SCA CONDITIONS OVER INLAND WATERS MAY BE MINIMAL
AT FIRST DUE TO LIMITED MIXING BUT WILL BECOME MORE FAVORABLE
THURSDAY MORNING. HAVE ADDED THE LOWER JAMES WITH TIMES STAGGERED
SLIGHTLY FROM THE BAY (STARTING AT 21Z TODAY AND ENDING 3 HOURS
EARLIER THURSDAY). LATER SHIFTS MAY NEED TO CONSIDER SCA BEHIND
THE COLD FRONT FOR OTHER RIVER ZONES ON THURSDAY MORNING.
SCA IS ALREADY IN EFFECT N OF PARRAMORE ISLAND. SEAS ARE EXPECTED TO
BUILD TO 5 FT OR HIGHER BY 18Z S OF THERE AND DECIDED TO BEGIN SCA S
OF PARRAMORE ISLAND AT 15Z TO ALLOW SUFFICIENT CUSHION.
HIGH PRESSURE THEN BUILDS INTO THE REGION ON THURSDAY NIGHT AND
LINGERS THROUGH SATURDAY AS A STRONG UPPER LEVEL RIDGE BUILDS INTO
THE SOUTHEASTERN US AND KEEPS STRONG HIGH PRESSURE AT THE SURFACE
OVER THE REGION THROUGH SATURDAY. LOW PRESSURE APPROACHES FROM THE
SW SUNDAY AND MOVES ACROSS THE REGION MONDAY. PRELIMINARY
INDICATIONS DO NOT INDICATE THAT A SCA WILL BE NEEDED WITH THIS
SYSTEM.
&&
.TIDES/COASTAL FLOODING...
WATER LEVELS AT BISHOPS HEAD AND CAMBRIDGE ARE EXPECTED TO
APPROACH MINOR FLOODING LATE TODAY AND EARLY THIS EVENING.
&&
.CLIMATE...
RECORD HIGHS FOR CHRISTMAS EVE/WED 12/24:
RICHMOND.......71 F (1988)
NORFOLK........75 F (1891)
SALISBURY......67 F (1990)
ELIZ CITY NC...75 F (1990)
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...COASTAL FLOOD ADVISORY UNTIL 8 PM EST THIS EVENING FOR
MDZ021>023.
NC...NONE.
VA...NONE.
MARINE...DENSE FOG ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ630>638-
650-652-654-656-658.
SMALL CRAFT ADVISORY UNTIL 4 PM EST THURSDAY FOR ANZ633-634-
650-652-654-656-658.
SMALL CRAFT ADVISORY UNTIL 4 PM EST THURSDAY FOR ANZ630>632.
SMALL CRAFT ADVISORY UNTIL 1 PM EST THURSDAY FOR ANZ638.
&&
$$
SYNOPSIS...AJZ/ALB
NEAR TERM...AJZ/MAM
SHORT TERM...AJZ/LKB
LONG TERM...ESS
AVIATION...LSA
MARINE...LSA
TIDES/COASTAL FLOODING...
CLIMATE...
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
723 AM EST WED DEC 24 2014
.SYNOPSIS...
A WARM FRONT WILL LIFT NORTHWARD THROUGH THE AREA THROUGH THIS
MORNING AS A LOW PRESSURE SYSTEM STRENGTHENS WEST OF THE MOUNTAINS.
AN ASSOCIATED COLD FRONT WILL CROSS THE AREA TONIGHT. HIGH PRESSURE
BUILDS BACK IN FROM THE SOUTHWEST CHRISTMAS DAY THROUGH FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
A DYNAMIC SYSTEM CONTINUES TO DEVELOP OVER THE CENTRAL GULF COAST
STATES AND TENNESSEE VALLEY EARLY THIS MORNING. LOCALLY...A RESIDUAL
COOL-WEDGE AIRMASS LINGERS WITH TEMPERATURES IN THE MID/UPPER 40S
W OF THE BAY. A WARM FRONT/COASTAL FRONT IS MOVING ONSHORE WITH
TEMPERATURES RISING INTO THE LOW/MID 60S OVER COASTAL SE VA AND NE
NC. THE FIRST BATCH OF RA HAS LIFTED NE OF THE LOCAL AREA. VSBYS
HAVE FALLEN IN THE WAKE OF THAT BATCH OF RA. THE LOWEST VSBYS ARE
ON THE COOL SIDE OF THE BOUNDARY FROM SOUTH CENTRAL VA ACROSS THE
HAMPTON ROADS AND INTERIOR NE NC. AN SPS HAS BEEN ISSUED TO
ACCOUNT FOR THIS. VSBY SHOULD RISE AS THE NEXT BATCH OF RAIN
ARRIVES FROM THE SW. DENSE FOG IS LIKELY TO DEVELOP OVER THE
WATER OVER THE NEXT FEW HOURS AS A WARM/MOIST AIRMASS OFF THE GULF
STREAM OVERSPREADS COOLER WATER.
THE NEXT BATCH OF RA WILL OVERSPREAD THE REGION THROUGH THE MORNING.
THE WARM FRONT SHOULD STEADILY LIFT SE-NW ACROSS THE COASTAL PLAIN
AND INTO THE I-95 CORRIDOR THIS MORNING AS THE LOW DEEPENS TO THE
W AND TRACKS NNE INTO THE OHIO VALLEY. A BLEND OF THE HI-RES ARW
AND HRRR RESULTS IN TEMPERATURES RISING INTO THE MID 60S TO NEAR
70 BY MIDDAY ROUGHLY ALONG AND E OF AN AVC-RIC-CGE LINE...WITH THE
WEDGE AIRMASS HOLDING STRONG OVER THE NW PIEDMONT.
PERIODS OF RA SHOULD CONTINUE THROUGH THE AFTERNOON. AS TEMPERATURES
AND DEWPOINTS RISE THERE IS A CHC OF THUNDER BY AFTERNOON WHEN
COMBINED WITH A STRONG SYSTEM TO THE W. CLOUDS/RA SHOULD LIMIT
DESTABILIZATION...SO SPC HAS ONLY THE SE PORTION OF THE AREA IN A
MARGINAL SEVERE RISK DESPITE A WARM MOISTURE RICH AIRMASS AND A
STRONG 925-700MB WIND FIELD. BY LATE AFTERNOON HIGHS SHOULD RANGE
FROM THE MID/UPPER 60S FOR CENTRAL PORTIONS TO AROUND 70 SE...WITH
MID/UPPER 50S OVER THE FAR NW PIEDMONT. HIGHS WILL BE NEAR
RECORDS...SEE THE CLIMATE SECTION BELOW FOR DETAILS.
THE COLD FRONT ARRIVES FROM THE W THIS EVENING AND MOVES W-E ACROSS
THE AREA AFTER MIDNIGHT. HIGH POPS CONTINUE THROUGH THE
EVENING...AND THEN RAPIDLY DIMINISH AFTER MIDNIGHT. A MENTION OF
THUNDER WILL BE MAINTAINED FOR THE AREA THROUGH THE EVENING...AND
THROUGH THE EARLY OVERNIGHT HOURS FOR COASTAL PORTIONS.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
DRIER AIR ARRIVES CHRISTMAS MORNING AS HIGH PRESSURE BUILDS IN FROM
THE W. A SLOWER FRONTAL PASSAGE WILL RESULT IN A MILD CHRISTMAS
MORNING WITH LOWS RANGING FROM THE MID 40S FAR W...TO THE MID/UPPER
50S SE. THE SKY SHOULD BECOME MAINLY SUNNY WITH SCT AFTERNOON CU
ALONG WITH BREEZY WESTERLY FLOW BY MID/LATE MORNING CHRISTMAS DAY.
HIGHS SHOULD RANGE FROM THE MID 50S TO LOWER 60S CHRISTMAS DAY AS
CAA IS WEAK AND WILL BE OFFSET BY DOWNSLOPE WARMING (AND DUE TO A
WARM BEGINNING).
CLEAR/SEASONABLE THURSDAY NIGHT WITH LOWS IN THE UPPER 20S TO MID
30S. SURFACE HIGH PRESSURE SETTLES IMMEDIATELY OFF THE COAST FRIDAY
RESULTING IN LIMITED MIXING/LIGHT WINDS AND SUNNY CONDITIONS. HIGHS
SHOULD GENERALLY BE IN THE 50S.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE MODELS ARE IN GOOD AGREEMENT TO BEGIN THE PERIOD FRIDAY NIGHT
WITH THE STRONG RIDGING OVER THE SOUTHEASTERN US AND HIGH PRESSURE
OVER THE SOUTHEAST...CENTERED OVER EASTERN VA/NC. BUT THE MODELS
STRUGGLE WITH THE BREAKING DOWN OF THE RIDGE WITH THE GFS BREAKING
IT DOWN MUCH MORE QUICKLY THAN THE ECMWF. THE GFS ALLOW THE NEXT
COLD FRONT TO DROP INTO THE ARE SAT NIGHT AND MOVES IT SOUTH OF
THE REGION BY SUNDAY MORNING...SETTING UP AN OVERRUNNING PATTERN
SUNDAY AFTERNOON INTO MONDAY MORNING. THE ECMWF...AND THE 12Z IS
FURTHER NORTH WITH FEATURES THAN 00Z RUN...KEEPS THE RIDGE MUCH
STRONGER OVER THE SE AND DOES NOT ALLOW THE COLD FRONT TO MOVE
THROUGH THE AREA SAT NIGHT. IT STALLS THE FRONT OVER THE AREA ON
SUNDAY AND AS A WAVE OF LOW PRESSURE FORMS ALONG THE BOUNDARY AND
LIFTS NE INTO THE CENTRAL APPALACHIANS...IT PUSHES GULF MOISTURE
INTO THE AREA. THE 00Z ECMWF PUSHED THE WAVE OFF THE COAST BY
MONDAY...BUT THE 12Z RUN LIFTS THE LOW TO THE NORTH AND DRAGS A
COLD FRONT ACROSS THE REGION ON TUESDAY.
SO FOR NOW WITH THE GREAT SPREAD IN THE MODELS...HAVE TRENDED
TOWARD HPC/WPC GUIDANCE...WHICH IS SIMILAR TO THE 00Z ECMWF AND
BROUGHT THE WAVE INTO THE REGION ON SUNDAY AFTERNOON AND EVENING
WITH IT EXITING BY MONDAY AFTERNOON. HAVE INCREASED POPS TO 50%
FOR THAT PERIOD...KEEPING SATURDAY DRY. HAVE ALSO GONE DRY ON
MONDAY NIGHT INTO TUESDAY. THE BIG DIFFERENCE COMES TO
TEMPERATURES AS THE GFS WOULD ALLOW MUCH COLD AIR INTO THE REGION
BEGINNING ON SUNDAY THROUGH TUESDAY. THIS COULD ALSO POTENTIALLY
LEAD TO SOME WINTRY PCPN WITH WAVE ON SUNDAY NIGHT. FOR NOW HAVE
KEPT TEMPERATURES ABOVE FREEZING AND ALL RAIN WITH THE COLD AIR
BEING KEPT MORE TO THE NORTH. FOR TEMPERATURES HAVE ALLOW FOR A
GRADUAL COOL DOWN THROUGH THE PERIOD WITH THE COLDEST AIR ARRIVING
ON TUESDAY WITH HIGHS IN THE 40S.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AS OF 12Z...ANOTHER BAND OF RAIN WAS PROGRESSING INTO THE CWA FROM
THE SW. CIGS AND VSBYS WILL CONTINUE TO BE VARIABLE BUT ARE
EXPECTED TO BE PREDOMINANTLY IFR OR LOWER THIS MORNING. A BIT OF
IMPROVEMENT IS EXPECTED THIS AFTERNOON AS THE AREA BECOMES WARM
SECTORED BUT THE TAF SITES SHOULD BE MAINLY IFR IS STILL EXCEPT AT
ORF AND ECG. CONFIDENCE IN THE DEGREE OF IMPROVEMENT IS MARGINAL.
A COLD FRONT APPROACHES FROM THE WEST TONIGHT WITH SHOWERS AND A
SLGT CHC OF THUNDER (THIS PCPN NOT INCLUDED IN THE TAF).
CONDITIONS IMPROVE FROM THE WEST IN THE MORNING AS WINDS TURN TO
WESTERLY.
OUTLOOK...HIGH PRESSURE DOMINATES THURSDAY AFTERNOON THROUGH
SATURDAY WITH DRY WEATHER. A CHC FOR RAIN RETURNS SUNDAY AS LOW
PRESSURE APPROACHES FROM THE WEST.
&&
.MARINE...
DENSE FOG ADVISORY IS IN EFFECT FOR THE MARINE AREA THROUGH LATE
THIS AFTERNOON AS WARM MOIST AIR MOVES OVER THE RELATIVELY COOL
WATERS.
AS OF 11Z...WINDS WERE BEGINNING TO INCREASE FROM THE SE. SCA
STARTED AT 15Z FOR THE MOUTH OF THE BAY AS WAVES WILL SOON REACH 4
FT IN THE CHANNEL.
PREVIOUS DISCUSSION...
AS OF 08Z...WINDS REMAIN LIGHT OVER THE MARINE AREA BUT ARE FORECAST
TO INCREASE FROM THE SE AND THEN S THIS MORNING AS A WARM FRONT
MOVES N THROUGH THE WATERS AND LOW PRESSURE DEEPENS OVER THE OHIO
VALLEY. SCA IS IN EFFECT FOR ALL THE WATERS EXCEPT THE RIVERS SAVE
THE LOWER JAMES. SCA CONDITIONS OVER INLAND WATERS MAY BE MINIMAL
AT FIRST DUE TO LIMITED MIXING BUT WILL BECOME MORE FAVORABLE
THURSDAY MORNING. HAVE ADDED THE LOWER JAMES WITH TIMES STAGGERED
SLIGHTLY FROM THE BAY (STARTING AT 21Z TODAY AND ENDING 3 HOURS
EARLIER THURSDAY). LATER SHIFTS MAY NEED TO CONSIDER SCA BEHIND
THE COLD FRONT FOR OTHER RIVER ZONES ON THURSDAY MORNING.
SCA IS ALREADY IN EFFECT N OF PARRAMORE ISLAND. SEAS ARE EXPECTED TO
BUILD TO 5 FT OR HIGHER BY 18Z S OF THERE AND DECIDED TO BEGIN SCA S
OF PARRAMORE ISLAND AT 15Z TO ALLOW SUFFICIENT CUSHION.
HIGH PRESSURE THEN BUILDS INTO THE REGION ON THURSDAY NIGHT AND
LINGERS THROUGH SATURDAY AS A STRONG UPPER LEVEL RIDGE BUILDS INTO
THE SOUTHEASTERN US AND KEEPS STRONG HIGH PRESSURE AT THE SURFACE
OVER THE REGION THROUGH SATURDAY. LOW PRESSURE APPROACHES FROM THE
SW SUNDAY AND MOVES ACROSS THE REGION MONDAY. PRELIMINARY
INDICATIONS DO NOT INDICATE THAT A SCA WILL BE NEEDED WITH THIS
SYSTEM.
&&
.TIDES/COASTAL FLOODING...
WATER LEVELS AT BISHOPS HEAD AND CAMBRIDGE ARE EXPECTED TO
APPROACH MINOR FLOODING LATE TODAY AND EARLY THIS EVENING.
&&
.CLIMATE...
RECORD HIGHS FOR CHRISTMAS EVE/WED 12/24:
RICHMOND.......71 F (1988)
NORFOLK........75 F (1891)
SALISBURY......67 F (1990)
ELIZ CITY NC...75 F (1990)
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...DENSE FOG ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ630>638-
650-652-654-656-658.
SMALL CRAFT ADVISORY UNTIL 4 PM EST THURSDAY FOR ANZ633-634-
654-656-658.
SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 4 PM EST
THURSDAY FOR ANZ630>632.
SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 1 PM EST
THURSDAY FOR ANZ638.
SMALL CRAFT ADVISORY UNTIL 4 PM EST THURSDAY FOR ANZ650-652.
&&
$$
SYNOPSIS...AJZ/ALB
NEAR TERM...AJZ
SHORT TERM...AJZ/LKB
LONG TERM...ESS
AVIATION...LSA
MARINE...LSA
TIDES/COASTAL FLOODING...
CLIMATE...
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
701 AM EST WED DEC 24 2014
.SYNOPSIS...
A WARM FRONT WILL LIFT NORTHWARD THROUGH THE AREA THROUGH THIS
MORNING AS A LOW PRESSURE SYSTEM STRENGTHENS WEST OF THE MOUNTAINS.
AN ASSOCIATED COLD FRONT WILL CROSS THE AREA TONIGHT. HIGH PRESSURE
BUILDS BACK IN FROM THE SOUTHWEST CHRISTMAS DAY THROUGH FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
A DYNAMIC SYSTEM CONTINUES TO DEVELOP OVER THE CENTRAL GULF COAST
STATES AND TENNESSEE VALLEY EARLY THIS MORNING. LOCALLY...A RESIDUAL
COOL-WEDGE AIRMASS LINGERS WITH TEMPERATURES IN THE MID/UPPER 40S
W OF THE BAY. A WARM FRONT/COASTAL FRONT IS MOVING ONSHORE WITH
TEMPERATURES RISING INTO THE LOW/MID 60S OVER COASTAL SE VA AND NE
NC. THE FIRST BATCH OF RA HAS LIFTED NE OF THE LOCAL AREA. VSBYS
HAVE FALLEN IN THE WAKE OF THAT BATCH OF RA. THE LOWEST VSBYS ARE
ON THE COOL SIDE OF THE BOUNDARY FROM SOUTH CENTRAL VA ACROSS THE
HAMPTON ROADS AND INTERIOR NE NC. AN SPS HAS BEEN ISSUED TO
ACCOUNT FOR THIS. VSBY SHOULD RISE AS THE NEXT BATCH OF RAIN
ARRIVES FROM THE SW. DENSE FOG IS LIKELY TO DEVELOP OVER THE
WATER OVER THE NEXT FEW HOURS AS A WARM/MOIST AIRMASS OFF THE GULF
STREAM OVERSPREADS COOLER WATER.
THE NEXT BATCH OF RA WILL OVERSPREAD THE REGION THROUGH THE MORNING.
THE WARM FRONT SHOULD STEADILY LIFT SE-NW ACROSS THE COASTAL PLAIN
AND INTO THE I-95 CORRIDOR THIS MORNING AS THE LOW DEEPENS TO THE
W AND TRACKS NNE INTO THE OHIO VALLEY. A BLEND OF THE HI-RES ARW
AND HRRR RESULTS IN TEMPERATURES RISING INTO THE MID 60S TO NEAR
70 BY MIDDAY ROUGHLY ALONG AND E OF AN AVC-RIC-CGE LINE...WITH THE
WEDGE AIRMASS HOLDING STRONG OVER THE NW PIEDMONT.
PERIODS OF RA SHOULD CONTINUE THROUGH THE AFTERNOON. AS TEMPERATURES
AND DEWPOINTS RISE THERE IS A CHC OF THUNDER BY AFTERNOON WHEN
COMBINED WITH A STRONG SYSTEM TO THE W. CLOUDS/RA SHOULD LIMIT
DESTABILIZATION...SO SPC HAS ONLY THE SE PORTION OF THE AREA IN A
MARGINAL SEVERE RISK DESPITE A WARM MOISTURE RICH AIRMASS AND A
STRONG 925-700MB WIND FIELD. BY LATE AFTERNOON HIGHS SHOULD RANGE
FROM THE MID/UPPER 60S FOR CENTRAL PORTIONS TO AROUND 70 SE...WITH
MID/UPPER 50S OVER THE FAR NW PIEDMONT. HIGHS WILL BE NEAR
RECORDS...SEE THE CLIMATE SECTION BELOW FOR DETAILS.
THE COLD FRONT ARRIVES FROM THE W THIS EVENING AND MOVES W-E ACROSS
THE AREA AFTER MIDNIGHT. HIGH POPS CONTINUE THROUGH THE
EVENING...AND THEN RAPIDLY DIMINISH AFTER MIDNIGHT. A MENTION OF
THUNDER WILL BE MAINTAINED FOR THE AREA THROUGH THE EVENING...AND
THROUGH THE EARLY OVERNIGHT HOURS FOR COASTAL PORTIONS.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
DRIER AIR ARRIVES CHRISTMAS MORNING AS HIGH PRESSURE BUILDS IN FROM
THE W. A SLOWER FRONTAL PASSAGE WILL RESULT IN A MILD CHRISTMAS
MORNING WITH LOWS RANGING FROM THE MID 40S FAR W...TO THE MID/UPPER
50S SE. THE SKY SHOULD BECOME MAINLY SUNNY WITH SCT AFTERNOON CU
ALONG WITH BREEZY WESTERLY FLOW BY MID/LATE MORNING CHRISTMAS DAY.
HIGHS SHOULD RANGE FROM THE MID 50S TO LOWER 60S CHRISTMAS DAY AS
CAA IS WEAK AND WILL BE OFFSET BY DOWNSLOPE WARMING (AND DUE TO A
WARM BEGINNING).
CLEAR/SEASONABLE THURSDAY NIGHT WITH LOWS IN THE UPPER 20S TO MID
30S. SURFACE HIGH PRESSURE SETTLES IMMEDIATELY OFF THE COAST FRIDAY
RESULTING IN LIMITED MIXING/LIGHT WINDS AND SUNNY CONDITIONS. HIGHS
SHOULD GENERALLY BE IN THE 50S.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE MODELS ARE IN GOOD AGREEMENT TO BEGIN THE PERIOD FRIDAY NIGHT
WITH THE STRONG RIDGING OVER THE SOUTHEASTERN US AND HIGH PRESSURE
OVER THE SOUTHEAST...CENTERED OVER EASTERN VA/NC. BUT THE MODELS
STRUGGLE WITH THE BREAKING DOWN OF THE RIDGE WITH THE GFS BREAKING
IT DOWN MUCH MORE QUICKLY THAN THE ECMWF. THE GFS ALLOW THE NEXT
COLD FRONT TO DROP INTO THE ARE SAT NIGHT AND MOVES IT SOUTH OF
THE REGION BY SUNDAY MORNING...SETTING UP AN OVERRUNNING PATTERN
SUNDAY AFTERNOON INTO MONDAY MORNING. THE ECMWF...AND THE 12Z IS
FURTHER NORTH WITH FEATURES THAN 00Z RUN...KEEPS THE RIDGE MUCH
STRONGER OVER THE SE AND DOES NOT ALLOW THE COLD FRONT TO MOVE
THROUGH THE AREA SAT NIGHT. IT STALLS THE FRONT OVER THE AREA ON
SUNDAY AND AS A WAVE OF LOW PRESSURE FORMS ALONG THE BOUNDARY AND
LIFTS NE INTO THE CENTRAL APPALACHIANS...IT PUSHES GULF MOISTURE
INTO THE AREA. THE 00Z ECMWF PUSHED THE WAVE OFF THE COAST BY
MONDAY...BUT THE 12Z RUN LIFTS THE LOW TO THE NORTH AND DRAGS A
COLD FRONT ACROSS THE REGION ON TUESDAY.
SO FOR NOW WITH THE GREAT SPREAD IN THE MODELS...HAVE TRENDED
TOWARD HPC/WPC GUIDANCE...WHICH IS SIMILAR TO THE 00Z ECMWF AND
BROUGHT THE WAVE INTO THE REGION ON SUNDAY AFTERNOON AND EVENING
WITH IT EXITING BY MONDAY AFTERNOON. HAVE INCREASED POPS TO 50%
FOR THAT PERIOD...KEEPING SATURDAY DRY. HAVE ALSO GONE DRY ON
MONDAY NIGHT INTO TUESDAY. THE BIG DIFFERENCE COMES TO
TEMPERATURES AS THE GFS WOULD ALLOW MUCH COLD AIR INTO THE REGION
BEGINNING ON SUNDAY THROUGH TUESDAY. THIS COULD ALSO POTENTIALLY
LEAD TO SOME WINTRY PCPN WITH WAVE ON SUNDAY NIGHT. FOR NOW HAVE
KEPT TEMPERATURES ABOVE FREEZING AND ALL RAIN WITH THE COLD AIR
BEING KEPT MORE TO THE NORTH. FOR TEMPERATURES HAVE ALLOW FOR A
GRADUAL COOL DOWN THROUGH THE PERIOD WITH THE COLDEST AIR ARRIVING
ON TUESDAY WITH HIGHS IN THE 40S.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
LIFR CIGS WERE MOST PROMINENT ACRS THE CWA HOWEVER SOME TEMPORARY
IMPROVEMENT HAS DEVELOPED...ESPECIALLY IN THE VSBY AND MOST OFTEN IN
SE PORTIONS. THE WARM FRONT IS STILL JUST E OF HATTERAS DESPITE SE
WINDS AND INCREASING TEMPERATURES TOWARD COASTAL AREAS OF OUR CWA.
WITH THAT IN MIND...ANY IMPROVEMENT IN CIGS ARE EXPECTED TO BE
TEMPORARY. AN AREA OF RAIN...BRIEFLY HEAVY...WAS MOVING QUICKLY NE
THROUGH THE AREA. EXPECT THAT ONCE THE HEAVIER PCPN MOVES OUT THAT
CONDITIONS WILL BE MORE CONSISTENTLY IFR.
THE WARM FRONT IS EXPECTED TO LIFT TO THE NW/N WEDNESDAY MORNING.
DESPITE THE FACT THAT LAVMOS AND NAM MOS HAVE PERSISTENT IFR AT THE
TAF SITES...GFS MOS AND NAM DMO (DIRECT MODEL OUTPUT MOS) HAVE SOME
MODEST IMPROVEMENT BY EARLY AFTN AT ORF AND ECG AND POSSIBLY PHF.
WITH WARM SECTORING EXPECTED ESPECIALLY AT THESE LOCATIONS...HAVE
MVFR BY AROUND 18Z AT ORF AND ECG. HAVE TRIED TO APPLY IMPROVEMENT
CONSERVATIVELY. MODELS TEND TO IMPROVE WIDESPREAD IFR CONDS TOO FAST
BUT AT THE SAME TIME CAN BE TOO LOW IN WARM SECTOR SITUATIONS.
THEREFORE...CONFIDENCE IN THIS PART OF THE FORECAST IS LOW.
OUTLOOK...CURRENT FORECAST HAS WIDESPREAD PCPN WITH SLGT CHC FOR
THUNDER WEDNESDAY NIGHT AND EARLY THURSDAY MORNING. THE COLD FRONT
MOVES THROUGH THURSDAY MORNING SHIFTING WINDS TO WESTERLY.
CONDITIONS SHOULD IMPROVE RATHER QUICKLY FOLLOWING THE FRONTAL
PASSAGE. HIGH PRESSURE DOMINATES THROUGH SATURDAY WITH DRY WEATHER.
A CHC FOR RAIN RETURNS SUNDAY AS LOW PRESSURE APPROACHES FROM THE
WEST.
&&
.MARINE...
WILL CONTINUE TO MONITOR THE NEED FOR A DENSE FOG ADVISORY THIS
MORNING OVER THE MARINE AREA AS WARM MOIST AIR MOVES IN OVER
RELATIVELY COOL WATER.
AS OF 08Z...WINDS REMAIN LIGHT OVER THE MARINE AREA BUT ARE
FORECAST TO INCREASE FROM THE SE AND THEN S THIS MORNING AS A WARM
FRONT MOVES N THROUGH THE WATERS AND LOW PRESSURE DEEPENS OVER THE
OHIO VALLEY. SCA IS IN EFFECT FOR ALL THE WATERS EXCEPT THE RIVERS
SAVE THE LOWER JAMES. SCA CONDITIONS OVER INLAND WATERS MAY BE
MINIMAL AT FIRST DUE TO LIMITED MIXING BUT WILL BECOME MORE
FAVORABLE THURSDAY MORNING. HAVE ADDED THE LOWER JAMES WITH TIMES
STAGGERED SLIGHTLY FROM THE BAY (STARTING AT 21Z TODAY AND ENDING
3 HOURS EARLIER THURSDAY). LATER SHIFTS MAY NEED TO CONSIDER SCA
BEHIND THE COLD FRONT FOR OTHER RIVER ZONES ON THURSDAY MORNING.
SCA IS ALREADY IN EFFECT N OF PARRAMORE ISLAND. SEAS ARE EXPECTED TO
BUILD TO 5 FT OR HIGHER BY 18Z S OF THERE AND DECIDED TO BEGIN SCA S
OF PARRAMORE ISLAND AT 15Z TO ALLOW SUFFICIENT CUSHION.
HIGH PRESSURE THEN BUILDS INTO THE REGION ON THURSDAY NIGHT AND
LINGERS THROUGH SATURDAY AS A STRONG UPPER LEVEL RIDGE BUILDS INTO
THE SOUTHEASTERN US AND KEEPS STRONG HIGH PRESSURE AT THE SURFACE
OVER THE REGION THROUGH SATURDAY. LOW PRESSURE APPROACHES FROM THE
SW SUNDAY AND MOVES ACROSS THE REGION MONDAY. PRELIMINARY
INDICATIONS DO NOT INDICATE THAT A SCA WILL BE NEEDED WITH THIS
SYSTEM.
&&
.TIDES/COASTAL FLOODING...
WATER LEVELS AT BISHOPS HEAD AND CAMBRIDGE ARE EXPECTED TO
APPROACH MINOR FLOODING LATE TODAY AND EARLY THIS EVENING.
&&
.CLIMATE...
RECORD HIGHS FOR CHRISTMAS EVE/WED 12/24:
RICHMOND.......71 F (1988)
NORFOLK........75 F (1891)
SALISBURY......67 F (1990)
ELIZ CITY NC...75 F (1990)
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...DENSE FOG ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ630>638-
650-652-654-656-658.
SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 4 PM EST
THURSDAY FOR ANZ630>634.
SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 1 PM EST
THURSDAY FOR ANZ638.
SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 4 PM EST
THURSDAY FOR ANZ654-656-658.
SMALL CRAFT ADVISORY UNTIL 4 PM EST THURSDAY FOR ANZ650-652.
&&
$$
SYNOPSIS...AJZ/ALB
NEAR TERM...AJZ
SHORT TERM...AJZ/LKB
LONG TERM...ESS
AVIATION...LSA
MARINE...LSA
TIDES/COASTAL FLOODING...
CLIMATE...
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
325 PM CST Wed Dec 24 2014
.SHORT TERM: (Through Tonight)
Issued at 325 PM CST Wed Dec 24 2014
An area of light rain possibly mixed with a few wet snowflakes
currently centered through St. Louis was moving east around 25-30
kts. This precipitation is occuring in association with a trailing
vort max within the cyclonic flow on the backside of the exiting
upper trof. Present indications are it should have exited or just
about exited the eastern CWA counties in south central/southwest IL
at 00z. There might be some lingering patchy drizzle for a few hours
into early evening. Satellite imagery has stratus hanging tough and
still well back into eastern KS and eastern OK at 21z. Trends along
with the RAP and NAM 925 mb RH suggests the clearing trend will be
slow and won`t commence in our CWA until well after midnight, and
the back edge of clouds around 50 miles west of STL at 12z Thursday.
The clouds will help keep temperatures a tad warmer overnight than
the previous forecast.
Glass
.LONG TERM: (Thursday through Next Wednesday)
Issued at 325 PM CST Wed Dec 24 2014
(Thursday through Saturday)
Primary focus thru this period will be precip chances late in the
period.
Mdls remain in good agreement thru Fri. Sfc winds quickly become sly
by tomorrow as ridge quickly moves off to the E. Expect current
cloud deck to move ewd tonight and shud be along/near the MS River
around 12z Thurs. These clouds shud be on the ern boarder of the CWA
by 18z. However, mdls suggest these low clouds will probably be
replaced with CI which shud hinder heating somewhat. Have therefore
kept temps twd the cooler guidance, esp across ern portions of the
CWA will clouds will linger. For Fri, have trended slightly warmer
as strong sly winds will be in place. However, with questions
regarding cloud cover, did not go as high as warmer MOS for now.
Cut off low over srn Rockies begins to open and eject into the
Plains by Fri evening. However, the GEM is a slower soln and
actually redevelops an upper low after the initial s/w is reaching
the nrn Plains. As this soln is an outlier, have trended away from
this soln and twd the other mdls which remain in good agreement.
Have kept PoPs in lower chance category for now as mdl soundings
suggest much of the QPF may be more DZ than RA. Not to mention that
the NAM and local WRF suggest the precip bifurcating with a branch
to the N and one to the S. However, with the trof approaching and
some low level forcing, light RA will be possible. Question becomes
p-types on Sat and Sat night as the cold air filters into the
region. While the GFS soundings suggest precip will end as a brief
period of IP, then SN, setup is typical of this area where precip
will likely end as RA just ahead of the surge of cold air. This is
more likely given the sfc ridge center is currently progd to be over
wrn KS. Regardless, close attention shud be paid to this time period
as mdls come into better agreement.
(Sunday through Wednesday)
Focus quickly turns to temps thru this period.
Will continue trends twd a GFS/ECMWF compromise due to issues with
the GEM mentioned above. The DGEX also becomes a fast outlier as the
next trof ejects into the Plains sometime on Wed.
Relatively cold air moves in place behind the cdfnt on Sat. A
secondary cdfnt is expected to push thru the region Sun night into
Mon ahead of the next system approaching the region late Mon night
into Wed. Have trended temps twd cooler guidance for Tues and beyond
placing temps nearly 20 degrees below seasonal avg.
A number of questions arise with the system on Tues/Wed. The GFS
cuts off an upper low over the swrn U.S. which it is known to do.
The ECMWF ejects this trof into the Plains, but given the weakening
jet upstream of this trof, am not convinced this soln is correct.
With both mdls suggesting very low QPF, will keep only slight chance
PoPs going for now with plenty of time to adjust. The one item both
mdls do agree on is the precip is expected to be all SN.
Tilly
&&
.AVIATION: (For the 18z TAFs through 18z Thursday Afternoon)
Issued at 1135 AM CST Wed Dec 24 2014
The back edge of IFR flight conditions was near a KVFR-KFSW line
late this morning with MVFR conditions extending well west into
the Plains. IFR flight conditions with light rain/drizzle and
possibly a few snowflakes will be predominate through the afternoon
across eastern MO into western IL including the St. Louis area
terminals. Conditions will be improving to MVFR during the afternoon
in central MO including KCOU. MVFR conditions will prevail much of
tonight at all terminals with gradual clearing and improvement to
VFR from late tonight into just past daybreak on Thursday.
Specifics for KSTL:
IFR flight conditions with light rain/drizzle will prevail through
the afternoon. I can`t rule out a few snowflakes but nothing of
significance is currently anticipated. Conditions will be improving
to MVFR by early evening and then prevail tonight. Clearing and
improvement to VFR is currently expected just past daybreak on
Thursday with increasing southerly winds during the day on Thursday.
Glass
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 32 50 38 53 / 10 0 0 10
Quincy 29 46 36 49 / 10 0 0 10
Columbia 29 50 39 51 / 10 0 0 10
Jefferson City 30 51 39 52 / 10 0 0 10
Salem 33 45 36 50 / 30 0 0 10
Farmington 31 47 38 51 / 10 0 0 10
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1151 PM CST Tue Dec 23 2014
.UPDATE:
Issued at 821 PM CST Tue Dec 23 2014
Digesting the 00Z NAM and HRRR runs and combined they continue to
support the going forecast with a band of rain developing
overnight along and east of the Mississippi River, then mixing/changing
to snow from west to east during the morning hours. Accumulation
will be most likely under the heaviest and most persistent band of
snow which looks to roughly align from KBLV to KTAZ. Only minor
changes were made to the forecast as the placement of the
mesoscale snowband and final adjustments to the forecast will be
a nowcasting exercise by the next shift.
Issued at 650 PM CST Tue Dec 23 2014
Quick update this evening to lower POPs, as it appears that other
than some areas of drizzle across southwest Illinois, the better
shower activity will not develop until after midnight. Still
appears that the majority of the precipitation should fall as rain
tonight, perhaps mixing with snow very late on the western fringe
of the precipitation that develops overnight.
Hope to have another update out by 10 PM after some of the 00Z
model guidance arrives regarding any changes needed to the
snowfall forecast for tomorrow.
CVKING
&&
.SHORT TERM: (Tonight through Wednesday Night)
Issued at 251 PM CST Tue Dec 23 2014
The main forecast issue remains the impending storm system and
potential for accumulating snowfall. The models have come into
much better agreement with mass fields than they exhibited 24
hours ago. Yet, there are still some large issues with thermal
fields, qpf, and speed of the system that are resulting in lower
than normal confidence and higher than normal uncertainty.
The overall scenario is unchanged. The upper low is in the
development process within the southern portion of the deep
positively tilted trof across OK. The guidance is fairly well
clustered lifting the upper low northeast into southwest MO by
daybreak Wednesday to near St. Louis at 18z and into the lower
Great Lakes region by 00z. In response the surface low currently
located along the front in LA will deepen and move through the TN
and OH Vallies over the next 24 hours. Initially the warm conveyor
belt and mid level frontogenetical forcing will be the key players,
with rain presently across AR increasing in coverage and spreading
northeast into southeast Missouri this evening and northeastward
into far east central MO and southwest IL overnight. Model consensus
indicates the thermal profiles should begin cooling sufficiently
on the western fringe of the rain shield after 09z for the rain to
mix and begin changing to snow. After 12z Wednesday the large
scale forcing/ascent really ramps up in association with the
ejecting mid/upper low and this should result in an upswing in
coverage and intensity of precipitation from east central MO into
south central and central IL, and accelerated changeover to snow.
All of the CWA should be entirely snow by 18z, as the deformation
zone precipitation begins shifting away from the CWA. Snow amounts
are still a tough call and there is lots of room for error. The
mean track of the H85 low would place the most-favored axis of
highest precipitation from around Belleville to Decatur, but
during some of the time the rain will be changing to snow. Also
surface temperatures will be in the 32-35F range and SLRs are
expected to be lower than normal with a wet snow expected. The new
forecast has the highest amounts along the aforementioned corridor
with a general 2-3 inches. I wouldn`t be surprised to see locally higher
totals, especially as you head northeastward into central IL.
Given potential the impacts of slushy/slippery roads and reduced
visibility on holiday travel, we have gone ahead an issued a winter
weather advisory even though these amounts are generally below
those we typically consider for an advisory.
Some residual non-accumulating light snow/flurries may linger from
east central MO into IL during the first part of the evening,
however this will be a short window. The system continues its
quick departure with ridging aloft already by 12z Thursday and low
level warm advection underway after 06z.
Glass
.LONG TERM: (Thursday through Next Tuesday)
Issued at 251 PM CST Tue Dec 23 2014
Pronounced warm advection and backing flow aloft in response to
new upstream amplification will dominate Christmas day. The snow
cover will likely be short-lived as temperatures moderate above
normal Thursday into Friday.
A deep and slow progressive long wave trof will then dominate the
upper air pattern into the weekend featuring separate northern and
southern stream components. Present indications are we should see
a cold front passage on Friday night with an attendant threat of
precipitation. An overrunning pattern could then set-up Saturday
into Sunday with snow possible in the deeper cold air, however the
models are quite variable in their depictions of the important features.
Glass
&&
.AVIATION: (For the 06z TAFs through 06z Wednesday Night)
Issued at 1124 PM CST Tue Dec 23 2014
Tricky low confidence fcst for Wed. A cold front has pushed thru
all the terminals this evng. CIGs should slowly lower to IFR by
Wed mrng and then remain in place thru the end of the fcst prd. An
upper lvl disturbance will force a sfc low across the deep south
to strengthen overnight as it moves to the ern Grt Lks by tomorrow
evng. An area of precip will dvlp and move towards the STL metro
area late tonight. There is some uncertainty about how far west
the precip shield will extend. Current guidance indicates that the
precip should mix with and potentially change over to snow for a
few hours Wed mrng, though new model solutions this evng are
beginning to trend away from this scenario. There is some question
about when or where the changeover to snow will occur. It is
possible that KSUS may not see much precip at all while KCPS has
accumulating snow during the late mrng into early aftn. Am not
confident that any terminal in the STL metro area will see snow.
If that occurs, then VSBYs are too low. Am not inclined to change
the fcst until the precip dvlps. There is another upper lvl
disturbance that will track into cntrl MO Wed mrng and then push
east thru the aftn producing some addtnl VFR -RASN. Any precip
should come to an end by evng.
Specifics for KSTL:
An area of precip is expected to dvlp south of the area and move
north into the terminal prior to sunrise. Precip is expected to mix
with and potentially switch over to all snow during the late mrng.
Am not confident in this scenario as new model guidance this evng
has trended away from this solution but, am inclined to leave the
basic details intact until the precip dvlps and details become
better defined. If the switch over to snow does not occur then
VSBYs are too low tomorrow aftn. The main precip shield should
lift north of the terminal by early aftn. Occnl VFR -RASN should
continue thru the remainder of the aftn in the wake of this system
and as another upper level disturbance approaches from cntrl MO.
IFR CIGs should hang tough thru 6Z.
2%
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...WINTER WEATHER ADVISORY from 6 AM to 6 PM CST Wednesday FOR
Jefferson MO-St. Charles MO-St. Louis City MO-St. Louis MO.
IL...WINTER WEATHER ADVISORY from 6 AM to 6 PM CST Wednesday FOR Bond
IL-Clinton IL-Fayette IL-Greene IL-Jersey IL-Macoupin IL-
Madison IL-Marion IL-Monroe IL-Montgomery IL-St. Clair IL-
Washington IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BILLINGS MT
837 PM MST THU DEC 25 2014
.UPDATE...
FORECAST IN GOOD SHAPE TONIGHT AND ONLY SOME MINOR ADJUSTMENTS
MADE. SNOW IS TAPERING OFF THIS EVENING FROM BILLINGS SOUTH AS
THE SYSTEM CONTINUES TO SINK SOUTHWARD. HAVE LOWERED POPS OVER
MOST OF OUR SOUTHERN AREAS TONIGHT AS LITTLE IF ANY ADDITIONAL
ACCUMULATIONS ARE EXPECTED. HRRR IS INDICATING FOG POSSIBLE IN
SHERIDAN WYOMING AND EXTENDING NORTHEAST TO EKALAKA OVERNIGHT.
DEW POINT/TEMPERATURE SPREADS ARE AROUND 4 TO 6 DEGREES. DRIER
AIR IS MOVING INTO THE AREA AND DO NOT ANTICIPATE FOG DEVELOPING
ANYWHERE ELSE TONIGHT. REMAINDER OF THE FORECAST ON TRACK AND NO
OTHER CHANGES MADE. RICHMOND
&&
.SHORT TERM...VALID FOR FRI AND SAT...
SNOW CONTINUES TO WIND DOWN AS FORCING SINKS SOUTH. KBLX RADAR
STILL SHOWING SOME RETURNS SOUTH OF BILLINGS FROM FORT SMITH TO
SHERIDAN. WILL KEEP HIGHER POPS GOING IN THESE LOCATIONS BUT NOT
EXPECTING MUCH ACCUMULATION AS SHERIDAN WAS ONLY AT 3 MILES
REDUCTION IN LIGHT SNOW. WILL DROP ALL HIGHLIGHTS.
WEAK UPPER AND LOWER LEVEL FLOW TAKES OVER FOR TONIGHT.
TEMPERATURE/DEWPOINT SPREADS WERE NOT GREAT. BUFKIT SOUNDINGS
WERE SHOWING A SHALLOW LAYER OF MOISTURE HANGING ON THROUGH THE
NIGHT ONCE THE MID LEVEL CLOUDS CLEAR. CLOUDS WERE SHOWING SIGNS
OF BREAKING UP AS CLOUD TOPS WARM. LIGHT SURFACE FLOW AND FAIRLY
WET SNOWFALL MAY LEAD TO PATCH FOG FORMING THIS EVENING AND
OVERNIGHT...SO ADDED TO THE GRIDS. DRIER AIR WILL EVENTUALLY WIN
OUT LATE TONIGHT.
WEAK NORTHERLY FLOW FOR FRIDAY...SO WILL KEEP FORECAST HIGHS
BELOW SEASONAL AVERAGES. WEAK ENERGY MOVES DOWN AND PROVIDES SOME
WEAK QG FORCING SO KEPT LOW POPS IN PLACE. FLOW BACKS FOR FRIDAY
NIGHT AND SATURDAY AS STRONG ENERGY DIVES INTO THE PACIFIC
NORTHWEST COAST. THIS TRANSITION WILL TIGHTEN UP THE SURFACE
PRESSURE PATTERN ALONG THE EAST SLOPES AND PRODUCE INCREASING
WINDS FOR LIVINGSTON. BUMPED WINDS UP QUITE A BIT FOR THIS PERIOD.
MAY NEED TO ISSUE AN ADVISORY FOR THIS IN THE NEAR FUTURE.
TEMPERATURES WILL MODERATE SATURDAY WITH LOW LEVEL DOWNSLOPE
FLOW. FORCING ALOFT INCREASES OVER THE WEST HALF OF THE AREA
SATURDAY NIGHT AND RAISED POPS FOR THIS. THE WESTERN UPPER TROUGH
WILL PUSH INTO THE GREAT BASIN LATE SATURDAY NIGHT AND SET THE
STAGE FOR AN ARCTIC PUSH FOR SUNDAY. TWH
.LONG TERM...VALID FOR SUN...MON...TUE...WED...THU...
THE EXTENDED HAS NOT CHANGED MUCH. SUNDAY IS STILL LOOKING GOOD
FOR ANOTHER SHOT AT SNOWFALL. MODELS ARE STILL SHOWING SIMILAR
SOLUTIONS TO THE PAST SEVERAL DAYS. A COLD FRONT WILL MOVE QUICKLY
THROUGH THE AREA SUNDAY MORNING. BEHIND THE FRONT WILL BE NORTH
WINDS. THIS IS GOING BE A GOOD SETUP FOR ANOTHER UPSLOPE SNOW
EVENT. WITH COLDER TEMPERATURES THAN THIS PAST SYSTEM...SNOW
RATIOS WILL BE HIGHER. WHILE QPF IS SLIGHTLY LIGHTER...SNOW
AMOUNTS MAY BE SIMILAR TO WHAT HAS FALLEN OVERNIGHT. DIFFERENCES
IN THE MODEL QPF ARE SMALL...SO HAVE NOT CHANGE QPF OR SNOW
AMOUNTS MUCH.
GOING INTO MONDAY AND TUESDAY TEMPERATURES ARE GOING TO BE COLD.
PER THE MODEL DISCUSSION FROM WPC...HAVE WEIGHTED TEMPERATURES A
BIT MORE TO THE EC TEMPERATURES. DID NOT GO FULLY THAT DIRECTIONS
AS THE RAW GUIDANCE WAS GOING FOR TWENTIES BELOW FOR LOWS MONDAY
NIGHT INTO TUESDAY. MUCH OF THE TEMPERATURES NEXT WEEK WILL BE
DEPENDENT ON HOW MUCH SNOW IS ON THE GROUND...SO THAT WILL HAVE
TO MONITORED GOING FORWARD. TEMPERATURES BEGIN TO WARM UP SLIGHTLY
BY MIDWEEK...BUT WILL REMAIN BELOW NORMAL. REIMER
&&
.AVIATION...
A FEW SNOW SHOWERS ARE STILL LINGERING AROUND KSHR AND KBIL. THE
SNOW SHOULD DIMINISH IN THE NEXT FEW HOURS AND GIVE WAY TO SOME
CLOUDINESS DURING THE OVERNIGHT HOURS. SOME LOW LYING AREAS MAY
SEE SOME FOGGY CONDITIONS BY MORNING...MOST NOTABLY EASTERN
TERMINALS. SINGER
&&
.PRELIMINARY POINT TEMP/POPS...
FRI SAT SUN MON TUE WED THU
-----------------------------------------------------------
BIL 008/025 009/026 016/022 901/003 915/006 901/025 014/027
21/B 11/B 36/J 53/J 21/B 11/N 11/B
LVM 000/025 002/026 014/024 905/006 913/010 002/025 014/030
11/B 12/S 46/J 42/J 11/B 11/B 11/B
HDN 006/026 004/026 014/024 000/005 916/005 903/023 014/027
22/S 11/B 25/J 53/J 21/B 11/B 11/B
MLS 012/026 011/028 017/021 000/005 908/006 001/023 015/026
12/S 11/B 25/J 42/J 11/B 11/B 11/B
4BQ 009/024 007/026 013/024 000/005 912/002 903/022 013/027
22/S 10/B 14/J 53/J 11/B 11/B 11/B
BHK 009/022 010/026 013/018 904/001 908/003 902/020 012/024
11/B 11/B 14/J 32/J 11/B 11/B 11/E
SHR 000/022 902/025 010/024 000/007 913/010 903/026 014/030
51/B 10/B 15/J 63/J 21/B 11/B 11/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1131 PM CST TUE DEC 23 2014
.UPDATE...
ISSUED AT 1124 PM CST TUE DEC 23 2014
PERSISTENT DEFORMATION-BAND PRECIPITATION HAS BEEN SHOWING SIGNS
OF DECREASING IN INTENSITY AND AREAL COVERAGE OVER THE LAST COUPLE
OF HOURS...BUT RADAR RETURNS CONTINUE TO FLARE UP FROM TIME TO
TIME ACROSS WESTERN IOWA AND ROTATE INTO EASTERN NEBRASKA. EXPECT
THIS TREND TO CONTINUE FOR SEVERAL HOURS PAST MIDNIGHT. HOWEVER
TEMPERATURES REMAIN ABOVE FREEZING IN PRECIP AREAS...SO ANY
SNOWFALL SHOULD REMAIN MINIMAL. OTHERWISE NORTHWEST WINDS GUSTING
OVER 20 MPH WILL HELP TO DRY OUT ROADS OVERNIGHT...BUT COULD STILL
SEE A FEW SLICK SPOTS IN THE MORNING AS TEMPERATURES DROP BELOW
FREEZING.
&&
.SHORT TERM...(TONIGHT THROUGH FRIDAY)
ISSUED AT 300 PM CST TUE DEC 23 2014
BAND OF GENERALLY LIGHT MIXED PRECIP CONTINUES TO TRACK SLOWLY
SOUTH ACROSS SOUTHEAST NEBRASKA AND SOUTHWEST IOWA AT 20Z. THIS
TREND IS EXPECTED TO CONTINUE INTO THE EVENING AS UPPER TROUGH
MOVES SLOWLY EAST. TEMPERATURES ARE IN THE MID TO UPPER 30S SO
WHATEVER SNOW DOES FALL MELTS FAIRLY QUICKLY. NDOR WEB CAMS SHOW
LITTLE TO NO SNOW COVER SOUTH OF A COLUMBUS TO TEKAMAH LINE.
LATEST RAP MODEL INDICATES A DIMINISHING TREND TO THE PRECIP THIS
EVENING WITH ONLY MINOR ACCUMULATIONS EXPECTED AS TEMPERATURES
FALL TO NEAR 32 THROUGH 06Z. STRONGER DYNAMICS SHIFT WELL EAST OF
THE AREA TONIGHT TO THE TENNESSEE AND LOWER OHIO VALLEY WITH
SHORT WAVE RIDGING BUILDING INTO THE NORTHERN PLAINS.
FORECAST SOUNDINGS SUGGEST DECREASING CLOUDS ACROSS THE AREA FOR
WEDNESDAY ALTHOUGH EASTERN AREAS MAY BE LIMITED TO LATE AFTERNOON
FOR ANY POTENTIAL VIEWING OF SUNSHINE. CLEARING TREND CONTINUES
WEDNESDAY NIGHT INTO THURSDAY BEFORE CLOUDS INCREASE ONCE AGAIN
THURSDAY NIGHT AND FRIDAY BEHIND THE NEXT COLD FRONT AND
APPROACHING UPPER TROUGH. SOME LIGHT SNOW IS LIKELY AGAIN WITH
THIS SYSTEM ON FRIDAY BUT NO MAJOR IMPACT ON TRAVEL IS EXPECTED.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 300 PM CST TUE DEC 23 2014
SNOW MAY LINGER INTO FRIDAY NIGHT FOR SOUTHERN PARTS OF THE AREA
THEN DRY BUT COLD FOR THE WEEKEND. STRONG TROUGHING DEVELOPS OVER
THE CENTRAL PART OF THE NATION EARLY NEXT WEEK WITH MUCH COLDER
AIR ON TAP FOR THE END OF THE YEAR.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1124 PM CST TUE DEC 23 2014
MVFR CIGS WILL BE THE RULE THROUGH AT LEAST MID AFTERNOON AT
EASTERN AFTERNOON TAF SITES BEFORE WESTERLY WINDS BEGIN TO DRY LOW
LEVELS FROM WEST TO EAST. KLNK AND KOMA COULD SEE A BRIEF IFR
CIG/VSBY THROUGH ABOUT 10Z WHEN RAIN OR SNOW MOVES OVER THOSE
SITES. PRECIPITATION SHOULD BE EAST OF ALL TAF SITES BEFORE 12Z.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...DERGAN
SHORT TERM...FOBERT
LONG TERM...FOBERT
AVIATION...DERGAN
AREA FORECAST DISCUSSION
NWS ELKO NV
215 PM PST WED DEC 24 2014
.SYNOPSIS...ON THE LATEST SATELLITE IMAGE THERE IS A SHIELD OF
CLOUDS FROM UTAH TO THE PACIFIC OCEAN. THIS LOW PRESSURE SYSTEM WILL
DELIVER A BATCH OF WINTRY WEATHER THIS EVENING....OVER NIGHT AND
TOMORROW. THE BULK OF THE SNOW IS ANTICIPATED OVER NIGHT. IN
ADDITION TO SNOW...EXPECTING GUSTY WINDS...BLOWING SNOW AND BRUTALLY
COLD TEMPERATURES.
&&
.SHORT TERM...TONIGHT THROUGH SATURDAY. AS ADVERTISED...EXPECTING A
SIGNIFICANT WINTER WEATHER STORM THIS EVENING...OVER NIGHT AND INTO
TOMORROW. THE NAM...THE GFS AND THE RAP ARE PRETTY CONSISTENT
BRINGING THE QPF INTO THE LKN CWA AFTER 4 PM TODAY. THE GFS ENSEMBLE
MEMBERS ARE TIGHTLY CLUSTERED WITH THE PLACEMENT OF THE SURFACE LOW
OVER NE NV...WHEREAS THE ECMWF INDIVIDUAL MEMBERS ARE ROUGHLY 50 TO
100 MILES SOUTH OF THE GFS MEAN. LITTLE SUBTLE DIFFERENCES LIKE THIS
WILL MAKE THE DIFFERENCE IN FINAL SNOW TOTAL ACCUMULATIONS. THE NCEP
RMOP IS WELL INTO BLUE TERRITIORY EVEN AT 24 HRS. BUT THE DYNAMICS
ARE IN PLACE FOR A SNOW AND WIND EVENT. KEPT HEADLINES IN
PLACE...BUT ADDED AN NPW FOR NORTHERN NYE. IN THE WAKE OF THE
FRONTAL PASSAGE...EXPECTING CAA AND ROBUST NORTHERLY FLOW.
.LONG TERM...SATURDAY NIGHT THROUGH NEXT WEDNESDAY. EC AND GFS IN
FAIRLY GOOD AGREEMENT WITH THE OVERALL PATTERN. EXPECT VERY COLD
AND LARGELY DRY WEATHER ACROSS NEVADA THIS WEEKEND AND INTO NEXT
WEEK. COLD FRONT DROPPING SOUTH FROM CANADA WILL IS EXPECTED TO BE
JUST NORTH OF THE IDAHO-NEVADA BORDER SATURDAY NIGHT. THE VERY COLD
PART OF THE AIRMASS ASSOCIATED WITH AN ARCTIC AIRMASS BEGINS TO MOVE
INTO CWA DURING THE DAY SUNDAY. SINCE THE AIRMASS IS COLD AND WITH
SOME LOW LEVEL MOISTURE AVAILABLE...EXPECT JUST MAINLY LIGHT SNOW
WITH HEAVIEST AMOUNTS IN THE UPSLOPE FAVORABLE AREAS THROUGH MONDAY.
THE COLD AIRMASS IS REINFORCED AND CONTINUES TO PUSH SOUTH OVER THE
CWA AS THE 700 MB TEMPERATURES DROP NEAR -20C BY MONDAY AFTERNOON.
WITH SNOW COVER...DAYTIME TEMPERATURES MONDAY IS EXPECTED TO BE ONLY
IN THE LOW 20S AND TUESDAY WILL BE LUCKY TO MAKE IT TO THE 20 DEGREE
MARK. HAVE DROP LOW TEMPERATURES 5 TO 15 DEGREES NEXT TUESDAY AND
WEDNESDAY WITH LOWS SHOULD BE -15 BELOW ZERO TO NEAR ZERO MOST
LOCATIONS TUESDAY AND WEDNESDAY MORNINGS. JH
&&
.AVIATION...CIGS WILL LOWER THIS EVENING WITH COLD FRONT EXPECTED TO
PUSH INTO WMC AROUND 01-02Z...EKO 03-04Z AND AROUND ELY 05-06Z.
AHEAD OF THE COLD FRONT...S/SW WINDS OF 15 TO 25KTS WITH G40KTS AT
ALL TAF SITES...FOLLOWED BY SEVERAL HOURS OF IFR/LIFR IN SN/BLSN AT
KWMC...KEKO AND KELY BEHIND THE FRONT. AFTER THE FRONTAL PASSAGE
AROUND 05Z...STRONG GUSTY NE WINDS OF 35 TO 45 KNOTS AT TPH WILL
DEVELOP. THESE GUSTY WINDS WILL CONTINUE THROUGH AT LEAST THURSDAY
AFTERNOON.
ADDITIONALLY...THIS EVENING AND OVER NIGHT...EXPECTING SNOW TO
ACCUMULATE ON THE RUNWAYS OF KEKO. THIS IS A HIGH CONFIDENCE
EVENT...AND SNOW IS VISIBLE OVER NE NV ON THE LATEST RADAR IMAGE.
ADDITIONAL IMPACTS TO THE AVIATION CUSTOMERS WILL
INCLUDE...OBSCURED MT TOPS...LIGHT TO OCNL MODERATE TURBULENCE
AND LIGHT TO MODERATE ICING. THIS STORM WILL ALSO IMPACT SLC ON
THURSDAY/FRIDAY...POSSIBLY IMPACTING COMMERCIAL TRAFFIC BETWEEN
EKO AND SLC.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 4 PM PST
THURSDAY FOR NORTHERN ELKO COUNTY-SOUTH CENTRAL ELKO COUNTY-
SOUTHWEST ELKO COUNTY-WHITE PINE COUNTY.
WINTER WEATHER ADVISORY UNTIL 10 AM PST THURSDAY FOR HUMBOLDT
COUNTY-NORTHERN LANDER COUNTY AND NORTHERN EUREKA COUNTY-
SOUTHERN LANDER COUNTY AND SOUTHERN EUREKA COUNTY.
WIND ADVISORY FROM 1 AM TO 4 PM PST THURSDAY FOR SOUTHEASTERN
ELKO COUNTY.
WINTER STORM WARNING FROM 7 PM THIS EVENING TO 4 PM PST THURSDAY
FOR RUBY MOUNTAINS AND EAST HUMBOLDT RANGE.
WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 10 AM PST
THURSDAY FOR NORTHEASTERN NYE COUNTY-NORTHWESTERN NYE COUNTY.
WIND ADVISORY FROM 10 PM THIS EVENING TO 4 PM PST THURSDAY FOR
NORTHEASTERN NYE COUNTY-NORTHWESTERN NYE COUNTY.
&&
$$
97/87/87
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
320 PM EST WED DEC 24 2014
.SYNOPSIS...
A STORM SYSTEM OVER THE EASTERN GREAT LAKES WILL BRING RAIN TO
OUR REGION THROUGH TONIGHT. A COLD FRONT EARLY CHRISTMAS
MORNING WILL BRING RAIN SHOWERS AND EVEN A FEW THUNDERSTORMS WITH
GUSTY WINDS. IT WILL BE WINDY AND CHILLY FOR THE REMAINDER OF
CHRISTMAS DAY WITH A CHANCE OF RAIN AND SNOW SHOWERS. A RIDGE OF
HIGH PRESSURE WILL BRING FAIR WEATHER TO OUR REGION ON FRIDAY.
&&
.NEAR TERM /THROUGH THURSDAY/...
RADARS SHOW PLENTY OF LIGHT RAIN WITH SOME PATCHES OF HEAVIER RAIN
MAINLY ACRS THE ERN 1/2 OF PA AND E OF I-81 IN C NY. THE RAIN WILL
CONT TO TRACK N TO NORTHEASTWARD INTO THE EVENING AND THERE LIKELY
WILL BE A LULL IN THE PRECIPITATION FOR MOST OF OUR AREA BY 00Z
WITH JUST SOME SPOTTY LIGHT RAIN SHOWERS AT BEST. THIS INITIAL
SHOT OF PRECIPITATION WAS ASSOCIATED WITH A SHORT WAVE RIPPLING
NORTHEASTWARD ACRS NY/PA. THIS FEATURE WAS SEEN WELL IN THE 850 MB WIND
FIELDS SHOW A LOW LEVEL WIND MAX ACRS PA AND NY POINTING INTO THE
RIGHT ENTRANCE REGION OF AN UPPER LEVEL JET STREAK OVER OUR AREA.
ONCE THIS LIFTS NE OF THE REGION LATER THIS AFTERNOON...THERE WILL BE A
LULL IN THE PRECIP UNTIL THE COLD FRONT WHICH WAS PRESENTLY
EXTENDED FROM SERN LWR MI TO FAR WRN OH TO CNTRL KY RACES
EASTWARD IN ASSCTN WITH A STRG UPPER LEVEL WAVE THAT WILL PASS THRU
THE REGION LATER TONIGHT. THIS FEATURE WILL BE THE IMPETUS TO
FORCE THIS FRONT THRU BETWEEN 3 AND 9Z ACRS C NY AND NE PA.
AS THIS UPPER LEVEL FEATURE WORKS E...IT WILL ACCELERATE THE LOW-
LEVEL WINDS TO ARND 60 TO 65 KNOTS AT 850 MB AS PER THE NAM JUST
IN ADVANCE OF THE FRONT. INDEED THE WINDS FROM THE LOWER TO MIDDLE
TROPOSPHERE WILL BE RACING AHEAD OF THIS FRONT LEADING TO
IMPRESSIVE SHEAR PROFILES. THE 0-1 KM SHEAR WAS PROGGED TO BE AT
50 KNOTS...WITH THE 0-3 KM SHEAR AT ABT THE SAME OF 50 KNOTS WITH
THE 0-5 KM SHEAR (MODEL SOUNDINGS ONLY HAVE EQUILIBRIUM LEVELS AT
ABT 5 KM)...OF 75 TO 80 KNOTS. TRADITIONAL 0-6KM SHEAR WHICH MIGHT
NOT APPLY AS MUCH HERE WUD BE ALMOST 100 KNOTS. MAIN PROBLEM IS
HOW UNSTABLE WITH THE LOWER AMS GET IN ADVANCE OF THIS FRNT. THERE
WILL BE INTENSE LL MOISTURE ADVECTION BUT IT WILL BE FAIRLY WARM
ALOFT FOR THIS TIME OF THE YEAR. MODEL SOUNDINGS LOOK ALMOST MOIST
ADIABATIC AHEAD OF FRONT WITH CAPES GENERALLY LESS THAN 100 J/KG.
HIGH RES CONVECTION ALLOWING MODELS INCLUDING THE HRRR (UNTIL 7Z)
AND THE WRFNMM AND WRFARW THRU 12Z THU ARE NOT SHWG ANY
ORGANIZED LINEAR CONVECTION LIKE PREVIOUS RUNS. FOR NOW WILL
CONTINUE MENTION OF THUNDER AND GUSTY WINDS IN FORECASTS AND
MENTION IN HWO AS IT WUD NOT TAKE MUCH TO MIX STRG WINDS DOWN.
EVENING SHIFT WILL HAVE TO MONITOR FOR THE DEVELOPMENT. IF A
SQUALL LINE DOES DEVELOP AND RACES EAST IT CUD SPELL A LOT OF
TROUBLE WITH HIGH WINDS.
AFTER FROPA...GRADIENT WINDS WILL PICK UP AND WE WILL SEE
LINGERING RAIN SHOWERS IN THE BACKLASH MOISTURE ACRS C NY AND NE
PA THU AM. TEMPERATURES WILL SLOWLY FALL AND THE RAIN WILL MIX
WITH SOME SNOW AT TIMES LATER IN THE DAY. WILL CONTINUE WIND
ADVISORIES FOR CHRISTMASN DAY AS WE CAN EASILY SEE WIND GUSTS
BETWEEN 40 AND 50 MPH ACRS OUR NRN 1/2 OF OUR FORECAST AREA MAINLY
N OF BGM AND ELM.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY/...
FOR THURSDAY NIGHT WINDS DIE DOWN AND ANY LINGERING SNSH OFF LAKE
ONTARIO WILL DIE DOWN AS HIGH PRESSURE BUILDS SOUTH OF THE REGION
WITH RIDGING NOSING NORTHWARD. TEMPERATURES WILL REMAIN ABOVE
NORMAL AS OUR AREA REMAINS UNDER A PACIFIC AIRMASS.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
GFS/ECWMF HAVE COME INTO BETTER AGREEMENT WITH THE LATEST MODEL
RUNS... INDICATING A FRONTAL PASSAGE LATE SATURDAY NIGHT THROUGH
SUNDAY FOLLOWED BY A RATHER QUIET EXTENDED FORECAST PERIOD
DOMINATED BY CANADIAN HIGH PRESSURE. SATURDAY WILL FEATURE DRY AND
UNSEASONABLY WARM WEATHER WITH HIGH TEMPERATURES APPROACHING 50 IN
MANY PLACES. A COLD FRONT IS FORECAST TO CROSS THE AREA LATE
SATURDAY NIGHT OR SUNDAY MORNING ACCOMPANIED BY A FEW SHOWERS.
COLDER AIR WILL THEN GRADUALLY FILTER SOUTHEAST ACROSS THE AREA
SUNDAY THROUGH TUESDAY. 850 MB TEMPERATURES ARE FORECAST TO FALL
TO AROUND -10 TO -12 OVER LAKE ONTARIO BY MONDAY BUT THE FLOW WILL
BE STRONGLY ANTICYCLONIC IMPLYING LOTS OF DRY AIR AND LOW
INVERSION HEIGHTS WITH LAKE EFFECT SNOW POTENTIAL AT A MINIMUM.
MEANWHILE A SERIES OF WAVES ARE FOERCAST TO TRACK WELL SOUTH OF
OUR AREA WITH PRECIPITATION REMAINING SOUTH OF THE MASON-DIXON
LINE. IF THIS PATTERN IS REALIZED... A COOL MOSTLY DRY PERIOD CAN
BE EXPECTED WITH TEMPERATURES NEAR TO SLIGHTLY BELOW NORMAL.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
UPDATED AT 1 PM... PERIODS OF RAIN AND DRIZZLE WILL PERSIST THIS
AFTERNOON IN A MILD MOIST FLOW PATTERN ACROSS THE AREA. CONDITIONS
WILL BE MOSTLY MVFR WITH AREAS OF IFR MOST COMMON AT HILLTOP
AIRPORTS SUCH AS BGM. 40 KT SOUTHERLY WINDS AT 2000 FEET AGL WILL
ALSO RESULT IN LOW LEVEL WIND SHEAR. A PERIOD OF MOSTLY DRY
WEATHER CAN BE EXPECTED THIS EVENING WITH MOSTLY MVFR CIGS AND
VSBYS... THEN A COLD FRONT WILL MOVE ACROSS THE AREA FROM 04Z-08Z
WITH HEAVIER SHOWERS AND GUSTY WINDS SHIFTING TO THE WEST. AFTER A
BRIEF PERIOD OF CLEARING... CLOUDS WILL OVERSPREAD THE AREA AGAIN
CHRISTMAS MORNING WITH MVFR CIGS.
WINDS WILL BE LIGHT FROM THE SOUTH-EAST TODAY THROUGH THIS
EVENING. A COLD FRONTAL PASSAGE BETWEEN 04Z-08Z WILL BE
ACCOMPANIED BY A WIND SHIFT TO WESTERLY WITH GUSTS OF 30-35 KTS IN
HEAVIER SHOWERS... THEN WESTERLY WINDS WILL CONTINUE THROUGH
CHRISTMAS DAY AVERAGING 10 TO 20 KTS WITH GUSTS TO 30 KTS.
OUTLOOK...
THU...BECOMING VFR/MVFR. WINDY WITH RAIN SHOWERS.
FRI/SAT...VFR.
SAT NGT TO SUN...MVFR/IFR. CHC RAIN OR SNOW.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...WIND ADVISORY FROM 5 AM TO 7 PM EST THURSDAY FOR NYZ009-
015>018-022-023-025-036-037-044>046-057.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...MSE
AVIATION...MSE
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
140 PM EST WED DEC 24 2014
.SYNOPSIS...
A STORM SYSTEM OVER THE EASTERN GREAT LAKES WILL BRING RAIN TO
OUR REGION THROUGH TONIGHT. A COLD FRONT EARLY CHRISTMAS
MORNING WILL BRING RAIN SHOWERS AND EVEN A FEW THUNDERSTORMS WITH
GUSTY WINDS. IT WILL BE WINDY AND CHILLY FOR THE REMAINDER OF
CHRISTMAS DAY WITH A CHANCE OF RAIN AND SNOW SHOWERS. A RIDGE OF
HIGH PRESSURE WILL BRING FAIR WEATHER TO OUR REGION ON FRIDAY.
&&
.NEAR TERM /THROUGH THURSDAY/...
RADARS SHOW PLENTY OF LIGHT RAIN WITH SOME PATCHES OF HEAVIER RAIN
MAINLY ACRS THE ERN 1/2 OF PA AND E OF I-81 IN C NY. THE RAIN WILL
CONT TO TRACK N TO NORTHEASTWARD INTO THE EVENING AND THERE LIKELY
WILL BE A LULL IN THE PRECIPITATION FOR MOST OF OUR AREA BY 00Z
WITH JUST SOME SPOTTY LIGHT RAIN SHOWERS AT BEST. THIS INITIAL
SHOT OF PRECIPITATION WAS ASSOCIATED WITH A SHORT WAVE RIPPLING
NORTHEASTWARD ACRS NY/PA. THIS FEATURE WAS SEEN WELL IN THE 850 MB WIND
FIELDS SHOW A LOW LEVEL WIND MAX ACRS PA AND NY POINTING INTO THE
RIGHT ENTRANCE REGION OF AN UPPER LEVEL JET STREAK OVER OUR AREA.
ONCE THIS LIFTS NE OF THE REGION LATER THIS AFTERNOON...THERE WILL BE A
LULL IN THE PRECIP UNTIL THE COLD FRONT WHICH WAS PRESENTLY
EXTENDED FROM SERN LWR MI TO FAR WRN OH TO CNTRL KY RACES
EASTWARD IN ASSCTN WITH A STRG UPPER LEVEL WAVE THAT WILL PASS THRU
THE REGION LATER TONIGHT. THIS FEATURE WILL BE THE IMPETUS TO
FORCE THIS FRONT THRU BETWEEN 3 AND 9Z ACRS C NY AND NE PA.
AS THIS UPPER LEVEL FEATURE WORKS E...IT WILL ACCELERATE THE LOW-
LEVEL WINDS TO ARND 60 TO 65 KNOTS AT 850 MB AS PER THE NAM JUST
IN ADVANCE OF THE FRONT. INDEED THE WINDS FROM THE LOWER TO MIDDLE
TROPOSPHERE WILL BE RACING AHEAD OF THIS FRONT LEADING TO
IMPRESSIVE SHEAR PROFILES. THE 0-1 KM SHEAR WAS PROGGED TO BE AT
50 KNOTS...WITH THE 0-3 KM SHEAR AT ABT THE SAME OF 50 KNOTS WITH
THE 0-5 KM SHEAR (MODEL SOUNDINGS ONLY HAVE EQUILIBRIUM LEVELS AT
ABT 5 KM)...OF 75 TO 80 KNOTS. TRADITIONAL 0-6KM SHEAR WHICH MIGHT
NOT APPLY AS MUCH HERE WUD BE ALMOST 100 KNOTS. MAIN PROBLEM IS
HOW UNSTABLE WITH THE LOWER AMS GET IN ADVANCE OF THIS FRNT. THERE
WILL BE INTENSE LL MOISTURE ADVECTION BUT IT WILL BE FAIRLY WARM
ALOFT FOR THIS TIME OF THE YEAR. MODEL SOUNDINGS LOOK ALMOST MOIST
ADIABATIC AHEAD OF FRONT WITH CAPES GENERALLY LESS THAN 100 J/KG.
HIGH RES CONVECTION ALLOWING MODELS INCLUDING THE HRRR (UNTIL 7Z)
AND THE WRFNMM AND WRFARW THRU 12Z THU ARE NOT SHWG ANY
ORGANIZED LINEAR CONVECTION LIKE PREVIOUS RUNS. FOR NOW WILL
CONTINUE MENTION OF THUNDER AND GUSTY WINDS IN FORECASTS AND
MENTION IN HWO AS IT WUD NOT TAKE MUCH TO MIX STRG WINDS DOWN.
EVENING SHIFT WILL HAVE TO MONITOR FOR THE DEVELOPMENT. IF A
SQUALL LINE DOES DEVELOP AND RACES EAST IT CUD SPELL A LOT OF
TROUBLE WITH HIGH WINDS.
AFTER FROPA...GRADIENT WINDS WILL PICK UP AND WE WILL SEE
LINGERING RAIN SHOWERS IN THE BACKLASH MOISTURE ACRS C NY AND NE
PA THU AM. TEMPERATURES WILL SLOWLY FALL AND THE RAIN WILL MIX
WITH SOME SNOW AT TIMES LATER IN THE DAY. WILL CONTINUE WIND
ADVISORIES FOR CHRISTMASN DAY AS WE CAN EASILY SEE WIND GUSTS
BETWEEN 40 AND 50 MPH ACRS OUR NRN 1/2 OF OUR FORECAST AREA MAINLY
N OF BGM AND ELM.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY/...
FOR THURSDAY NIGHT WINDS DIE DOWN AND ANY LINGERING SNSH OFF LAKE
ONTARIO WILL DIE DOWN AS HIGH PRESSURE BUILDS SOUTH OF THE REGION
WITH RIDGING NOSING NORTHWARD. TEMPERATURES WILL REMAIN ABOVE
NORMAL AS OUR AREA REMAINS UNDER A PACIFIC AIRMASS.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
130 AM UPDATE...
LITTLE CHANGE. WPC GUIDANCE FOLLOWED THE SAME TUNE. TRICKY PART
WILL BE LOW LEVEL TEMPERATURES AND WHAT PRECIP TYPES EACH SYSTEM
WILL HAVE. TEMPERATURES WAVER AROUND FREEZING DEPENDING ON THE
STORM TRACKS. COOLING TUESDAY AND WEDNESDAY SO PROBABLY BY THEN
ALL SNOW AND BELOW NORMAL TEMPERATURES.
PREVIOUS DISCUSSION...
THE OVERALL 500 MB PATTERN DOES NOT CHANGE MUCH THROUGH THIS
PERIOD WITH A BROAD TROF RESIDENT OVER CENTRAL NORTH AMERICA WITH
RELATIVELY MILD SWLY FLOW ACROSS THE CNY/NEPA REGION. THIS WILL
KEEP US IN A RATHER ACTIVE PATTERN WITH TRANSIENT WEATHER SYSTEMS
MOVING THROUGH THE REGION.
MEDIUM RANGE MODEL CONSENSUS IS RATHER POOR...BUT IT DOES APPEAR
THE BEST CHANCE FOR PRECIPITATION WILL BE SAT NIGHT-SUN ASSOCIATED
WITH A COLD FRONT...AND THEN A MORE MARGINAL EVENT SLATED FOR
MONDAY AS LOW PRESSURE LIFTS THROUGH THE TN/OH VALLEY PER THE
ECMWF. THIS IS UNLESS THE GFS/GGEM CONTINUE TO TREND A FLATTER
WAVE OUT TO SEA TO OUR SOUTH MISSING US COMPLETELY. WPC GRIDS SEEM
TO BE HEAVY HANDED ON THE ECMWF SOLUTIONS...BUT GIVEN UNCERTAINTY
INTRODUCED BY GFS/GGEM...WE HAVE SOFTENED THEM TO CHANCE POPS IN
THIS AREA FROM SUN-MON NGT. BEYOND THEN...WEAK WAVES AND PASSING
FLURRIES POSSIBLE THROUGH MID-WEEK.
OVERALL...TEMPERATURES WITHIN THE BROAD SWLY FLOW WILL BE NEAR TO
ABOVE LATE DECEMBER NORMALS.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
UPDATED AT 1 PM... PERIODS OF RAIN AND DRIZZLE WILL PERSIST THIS
AFTERNOON IN A MILD MOIST FLOW PATTERN ACROSS THE AREA. CONDITIONS
WILL BE MOSTLY MVFR WITH AREAS OF IFR MOST COMMON AT HILLTOP
AIRPORTS SUCH AS BGM. 40 KT SOUTHERLY WINDS AT 2000 FEET AGL WILL
ALSO RESULT IN LOW LEVEL WIND SHEAR. A PERIOD OF MOSTLY DRY
WEATHER CAN BE EXPECTED THIS EVENING WITH MOSTLY MVFR CIGS AND
VSBYS... THEN A COLD FRONT WILL MOVE ACROSS THE AREA FROM 04Z-08Z
WITH HEAVIER SHOWERS AND GUSTY WINDS SHIFTING TO THE WEST. AFTER A
BRIEF PERIOD OF CLEARING... CLOUDS WILL OVERSPREAD THE AREA AGAIN
CHRISTMAS MORNING WITH MVFR CIGS.
WINDS WILL BE LIGHT FROM THE SOUTH-EAST TODAY THROUGH THIS
EVENING. A COLD FRONTAL PASSAGE BETWEEN 04Z-08Z WILL BE
ACCOMPANIED BY A WIND SHIFT TO WESTERLY WITH GUSTS OF 30-35 KTS IN
HEAVIER SHOWERS... THEN WESTERLY WINDS WILL CONTINUE THROUGH
CHRISTMAS DAY AVERAGING 10 TO 20 KTS WITH GUSTS TO 30 KTS.
OUTLOOK...
THU...BECOMING VFR/MVFR. WINDY WITH RAIN SHOWERS.
FRI/SAT...VFR.
SAT NGT TO SUN...MVFR/IFR. CHC RAIN OR SNOW.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...WIND ADVISORY FROM 5 AM TO 7 PM EST THURSDAY FOR NYZ009-
015>018-022-023-025-036-037-044>046-057.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...JAB/TAC
AVIATION...MSE/TAC
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
156 AM EST WED DEC 24 2014
.SYNOPSIS...
A STORM SYSTEM OVER THE EASTERN GREAT LAKES WILL BRING RAIN TO
OUR REGION INTO WEDNESDAY NIGHT. A COLD FRONT EARLY CHRISTMAS
MORNING WILL BRING RAIN SHOWERS AND EVEN A FEW THUNDERSTORMS WITH
GUSTY WINDS. IT WILL BE WINDY AND CHILLY FOR THE REMAINDER OF
CHRISTMAS DAY WITH A CHANCE OF RAIN AND SNOW SHOWERS. A RIDGE OF
HIGH PRESSURE WILL BRING FAIR WEATHER TO OUR REGION ON FRIDAY.
&&
.NEAR TERM /THROUGH TODAY/...
940 PM UPDATE...
CHANGED POP GRIDS OVERNIGHT TO REFLECT THE RAIN ADVANCING INTO THE
FA FROM THE WEST BETWEEN 7Z AND 11Z. STUCK TO CATEGORICAL POPS FOR
THE EARLY MORNING HOURS ONCE THE RAIN GETS ESTABLISHED NEAR SUNRISE.
ALSO REWORKED THE TEMPERATURE GRIDS AS IT APPEARS WE HAVE ALREADY
SEEN OUR MINS FOR THE NIGHT. TEMPERATURES ARE HOLDING STEADY OR
RISING ATTM. USING A BLEND OF THE HRRR AND LAMP, WE CAME UP WITH A
REALISTIC LOOKING HOURLY TEMPERATURE PROG FOR THE OVERNIGHT. THE
RAP INITIALIZED WAY TOO COLD AT THE SURFACE OVER THE EAST, SO WE
THREW IT OUT THIS RUN.
130 PM UPDATE...
RADARS SHOW AN AREA OF RAIN ACROSS NC AND ERN NY AND THE LATEST
HRRR HAS DONE A DECENT JOB OF SIMULATING THIS. THIS PRECIPITATION
WAS ASSCTD WITH A SHORT WAVE THAT WAS MAKING ITS WAY INTO NEW
ENGLAND. THE HRRR ADVECTS THIS RAIN EASTWARD BY 20-21Z W/ NE PA
AND C NY CONTINUING UNDER A VERY MOIST SERLY LOW-LEVEL FLO. THIS
MOIST FLO WILL CONT PATCHY AREAS OF LIGHT RAIN AND DRIZZLE INTO
THE EVENING AND OVERNIGHT HOURS AS OUR AREA WILL BE IN A LULL IN
THE HEAVIER RAINS. A MUCH MORE SIGNIFICANT AND LARGER PRECIPITATION
SHIELD WILL ARRIVE BTWN ABT 9 AND 12Z WED FROM S TO N ACRS NE PA/C
NY. THE DYNAMICS AND MOISTURE TRANSPORT WERE FAIRLY IMPRESSIVE
FOR WED/WED EVE.
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOWS A LARGE UPPER LEVEL
WAVE PRESENTLY OVER TEXAS MOVING INTO THE BASE OF A LONG WAVE
TROF. THE DYNAMIC TROPOPAUSE WAS DOWN TO ABT 530 MB WITH THIS
FEATURE. THIS WAVE WILL RIDE NE UP THRU THE MIDWEST WEDNESDAY AND
CLOSE OFF TO A 500 MB LOW BY 00Z THU OVER LWR MI. AS THIS OCCURS
OUR AREA COMES UNDER DEEP UPPER LEVEL DVRG AND AN ACCELERATING
S-SWRLY LOW-LEVEL FLOW WHICH PEAKS AT ABT 50 KNOTS AT 850 MB WED
AFTERNOON AND EVENING. ALL THE SYNOPTIC SCALE MODELS INDICATE A
MAX IN QPF EAST OF A LINE FROM ABT AVP TO ALB. THE FINGER LAKES
REGION TO WRN NY IS IN A LOCAL MINIMUM ON ALL SYNOPTIC MODELS
INCLUDING 12Z EURO...12Z GFS...12Z NAM AND 12Z CMC. THIS MAKES
SENSE AS THE LL FLOW IS S-SWRLY AND THE LLJ WHICH FOCUSES MOISTURE
AND PRECIPITATION WILL BE SPLIT BY THE APPLCNS. THE EURO...GFS AND
CMC ALL AGREE THAT THE MAXIMUM QPF IS BTWN 1 AND 1.5 INCHES MAINLY
ACRS AREAS E OF A LINE FROM AVP TO DELAWARE CO NY IN OUR FORECAST
AREA WITH .25 TO .5 INCHES QPF IN THE FINGER LAKES. THE NAM IS
HEAVY HANDED WITH THE QPF AND HAS OVER 2 INCHES IN OUR FAR ERN
ZONES AND .5 INCHES IN THE FINGER LAKES. ONLY LOCALLY CUD I SEE 2
INCHES IN THE CATSKILLS AND POCONOS...BUT NOT WIDESPREAD ENUF TO
CAUSE SIGNIFICANT HYDRO ISSUES. SNOWPACK WAS MINIMAL IN THESE
AREAS SO WE ARE EXPECTING RISES TO AT LEAST 1/2 TO 3/4 BANKFUL
ON MANY RIVERS AND TRIBUARTIES BUT NO FLOOD ISSUES OF SIGNIFICANCE
OTHER THAN URBAN FLOODING. SO NO FLOOD WATCH AT THIS TIME. PRECIP
WILL CONTINUE INTO WED EVE OFF AND ON. TEMPERATURES WILL HOLD
STEADY AND SLOWLY RISE THRU WEDNESDAY.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
FOR WEDNESDAY NIGHT...MAIN CONCERN IS THE POTENTIAL FOR A QLCS OR
NARROW COLD FRONTAL RAIN BAND ALONG THE COLD FRONT WHICH SWINGS
THRU THE REGION BY 4-8Z THU. TIMING OF THIS FRONT IS STILL UNCERTAIN
BUT IT APPEARS IT WILL COME THRU JUST AFTER MIDNIGHT OR SO. THE
DYNAMICS ARE VERY IMPRESSIVE AS ALL SYNOPTIC MODELS SHOW A STRG
UPPER LEVEL PV MAX SWINGING THRU WITH SRG DVRG ALOFT ERLY THU AM.
THE LOW TO MID LEVEL WINDS AT FROPA WERE VERY STRG WITH 0-1 KM
BULK SHEAR AT 45 KNOTS, 0-3 KM ARND 50-60 KNOTS AND 0-6 KM FROM 80
TO 100 KNOTS DEPENDING ON THE MODEL. 0-1 KM HELICITIES WERE
PROGGED CLOSE TO 300 M2/S2. CAPES WERE MARGINAL WHICH IS TO BE
EXPECTED... RUNNING POTENTIALLY UP TO 250 J/KG OR SO MAINLY IN OUR
ERN ZONES. DEWPOINTS ARE PROJECTED TO CLIMB ABV 50F IN THE SRLY
FLOW...ESPECIALLY ACRS NE PA TO EC NY. MODELS SHOW THAT THE DWPTS
AT 850 MB CLIMB ABV 10C WHICH IS 50F AS WELL ACRS ENTIRE AREA. WE
RAN OUR LOCAL SVR WX ANALOG CHECKLIST WHICH COMPARES FORECAST
PARAMETERS WITH HISTORICAL EVENTS AND IT RETURNED 4 OUT OF 5
EVENTS THAT HAD SIGNIFICANT WIND DAMAGE. 3 OF THE 5 EVENTS HAD
ISOLATED TORNADOES INCLUDING THE F2 OF DEC 2006 WHICH HIT NE PA.
FOR NOW HAVE MENTION OF THUNDERSTORMS WITH GUSTY WINDS IN GRIDS
WED NGT/ERLY THU. WILL HIGHLIGHT POTENTIAL FOR STRONG TO LOCALLY
SEVERE THUNDERSTORMS IN THE HWO AS SPC HAS SOME OF OUR AREA IN A
MARGINAL RISK.
AFTER FROPA ON CHRISTMAS DAY...IT WILL BE WINDY WITH PRESSURE
RISES OF ABT 10 TO 15 MB / 12 HOURS IN C NY WHICH IS CLOSE TO
ADVY CRITERIA. WILL MENTION POTENTIAL FOR WIND GUSTS TO 50 MPH IN
HWO FOR C NY...MAINLY FINGER LAKES REGION TO SYR/RME AREAS. THERE
WILL ALSO BE SCT RAIN AND SNOW SHOWERS ARND IN THE BACKLASH OF
THIS LARGE CYCLONE WHICH TAPERS OFF THU NGT.
FRIDAY WILL BE FAIR AND STILL MILD AS A RDG OF HIGH PRESSUIE
BUILDS ACRS THE REGION AS HGHTS RAPIDLY RISE.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
130 AM UPDATE...
LITTLE CHANGE. WPC GUIDANCE FOLLOWED THE SAME TUNE. TRICKY PART
WILL BE LOW LEVEL TEMPERATURES AND WHAT PRECIP TYPES EACH SYSTEM
WILL HAVE. TEMPERATURES WAVER AROUND FREEZING DEPENDING ON THE
STORM TRACKS. COOLING TUESDAY AND WEDNESDAY SO PROBABLY BY THEN
ALL SNOW AND BELOW NORMAL TEMPERATURES.
PREVIOUS DISCUSSION...
THE OVERALL 500 MB PATTERN DOES NOT CHANGE MUCH THROUGH THIS
PERIOD WITH A BROAD TROF RESIDENT OVER CENTRAL NORTH AMERICA WITH
RELATIVELY MILD SWLY FLOW ACROSS THE CNY/NEPA REGION. THIS WILL
KEEP US IN A RATHER ACTIVE PATTERN WITH TRANSIENT WEATHER SYSTEMS
MOVING THROUGH THE REGION.
MEDIUM RANGE MODEL CONSENSUS IS RATHER POOR...BUT IT DOES APPEAR
THE BEST CHANCE FOR PRECIPITATION WILL BE SAT NIGHT-SUN ASSOCIATED
WITH A COLD FRONT...AND THEN A MORE MARGINAL EVENT SLATED FOR
MONDAY AS LOW PRESSURE LIFTS THROUGH THE TN/OH VALLEY PER THE
ECMWF. THIS IS UNLESS THE GFS/GGEM CONTINUE TO TREND A FLATTER
WAVE OUT TO SEA TO OUR SOUTH MISSING US COMPLETELY. WPC GRIDS SEEM
TO BE HEAVY HANDED ON THE ECMWF SOLUTIONS...BUT GIVEN UNCERTAINTY
INTRODUCED BY GFS/GGEM...WE HAVE SOFTENED THEM TO CHANCE POPS IN
THIS AREA FROM SUN-MON NGT. BEYOND THEN...WEAK WAVES AND PASSING
FLURRIES POSSIBLE THROUGH MID-WEEK.
OVERALL...TEMPERATURES WITHIN THE BROAD SWLY FLOW WILL BE NEAR TO
ABOVE LATE DECEMBER NORMALS.
&&
.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
1230 AM UPDATE...
MILD MOIST CONDITIONS WILL REMAIN ACROSS THE AREA TONIGHT WITH
MVFR AND IFR CIGS AND MOSTLY MVFR TO VFR VSBYS. AS RAIN MOVES IN
FROM THE SW 8 TO 12Z CIGS SHOULD LOWER TO IFR MOST LOCATIONS AND
VSBYS WILL FALL TO MVFR. CONDITIONS WILL BE FAIRLY PERSISTENT INTO
THIS EVENING. SOME IMPROVEMENT POSSIBLE ELM TOWARD 04Z AND THE
FROPA.
OTHER PROBLEM A STRONG LOW LEVEL JET MOVING IN MIDDAY AND
REMAINING INTO TONIGHT. KEPT THE LLWS GROUP ALL SITES WITH A JET
OUT OF THE SOUTH AT 40 TO 45 KTS.
SFC WINDS E TO SE AT 10 KTS OR LESS. ELM SHIFTING TO S THIS EVE
AND REST CLOSER TO 6Z.
OUTLOOK...
WED NGT...IFR. PERIODS OF RAIN.
THU...BECOMING VFR/MVFR. WINDY WITH RAIN SHOWERS.
FRI/SAT...VFR.
SAT NGT TO SUN...MVFR/IFR. CHC RAIN OR SNOW.
&&
.HYDROLOGY...
WITH THE RAINFALL THE NEXT 3 DAYS RIVERS WILL RISE. IT SHOULD BE
SPREAD OUT ENOUGH THAT RIVER AND FLASH FLOODING IS NOT EXPECTED.
RAINFALL AMOUNTS OF HALF INCH IN THE FAR W AND NW TO 1 TO 1.5
INCHES IN THE FAR SE. RAINFALL MAXES ALONG THE COAST OUTSIDE THE
CWA. HALF AN INCH TO AN INCH ACROSS THE HEADWATERS OF THE NORTH
BRANCH SUSQUEHANNA AND DELAWARE. THIS IS THE AREA TO WATCH WITH
SNOW STILL ON THE GROUND AND EXPECTED TO MELT WITH STRONG WINDS
AND HIGH DEWPOINTS. THIS WOULD ADD AN ANOTHER INCH OF RUNOFF FROM
SNOWMELT. MARFC HAS SEVERAL POINTS GETTING TO CAUTION STAGE BUT
NOT FLOOD. SEEMS REASONABLE. FLASH FLOOD NOT EXPECTED WITH LOW
RAINFALL RATES. HIGHEST RATES UNDER HALF AN INCH AN HOUR THIS AFTN
AND EVE AHEAD OF THE FRONT. ALMOST ALL THE RAIN WILL RUN OFF.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN/DJP
NEAR TERM...DJN/DJP
SHORT TERM...DJN
LONG TERM...JAB/TAC
AVIATION...TAC
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1210 PM EST WED DEC 24 2014
.SYNOPSIS...A WARM FRONT WILL LIFT NORTHWARD THROUGH THE CAROLINAS
TODAY AS A DEEPENING LOW PRESSURE SYSTEM TRACKS INTO THE TENNESSEE
VALLEY. A COLD FRONT WILL SURGE EAST ACROSS THE REGION TONIGHT AS
THE SURFACE LOW PROGRESSES NORTHWARD THROUGH THE OHIO VALLEY INTO
THE GREAT LAKES.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 1050 AM WEDNESDAY...
LARGE WARM CONVEYOR BELT PRECIP SHIELD STRETCHES FROM THE MID-
ATLANTIC COAST TO THE GULF OF MEXICO...WITH AN EMBEDDED QLCS FROM
SOUTH CAROLINA THROUGH THE FLORIDA PANHANDLE. MEANWHILE...THE WEDGE
AND COASTAL FRONTS CONTINUE THEIR RETREAT THROUGH THE COASTAL PLAIN
AND INTO THE PIEDMONT THIS MORNING...LEADING TO A STRONG BAROCLINIC
ZONE JUST EAST OF THE US-1 CORRIDOR. TEMPS ARE STILL IN THE MID 40S
NORTHWEST TO NOW UPPER 60S SOUTHEAST. THE BULK OF THE PRECIP WILL
CONTINUE TO SHIFT EAST THROUGH EARLY AFTERNOON IN CONCERT WITH THE
LOW-LEVEL JET....WITH SOME ENHANCEMENT ALONG THE AFOREMENTIONED
FRONTAL ZONE. A LULL IN PRECIP IS ANTICIPATED THIS AFTERNOON ON THE
HEELS OF THE LOW-LEVEL JET...WITH FORCING SOMEWHAT LIMITED GIVEN
THAT THE POSITIVELY TILTED UPPER TROUGH OVER THE MISSISSIPPI RIVER
VALLEY DOESNT MAKE ITS STRONG EASTWARD PUSH UNTIL TONIGHT. MOST OF
THE CAM`S SUPPORT THIS IDEA...WITH JUST ISOLATED TO WIDELY SCATTERED
SHOWERS AFTER 18Z. THE THREAT OF AN SEVERE WEATHER SHOULD REMAIN
CONFINED TO THE COASTAL PLAIN...WHERE MARGINAL CAPE AND STRONG
SHEAR PHASE THIS AFTERNOON. MODIFIED RAP SOUNDINGS SUGGEST 200-300
J/KG MLCAPE EAST OF I-95 IN THE TRUER WARM SECTOR... WITH 50-60KT
BULK SHEAR. HOWEVER...LOW-LEVEL HODOGRAPHS WILL BECOME MORE LINEAR
WITH TIME AS THE SURFACE WINDS CONTINUE TO VEER TO MORE
SOUTHWESTERLY....SO UNLESS THERE IS LOCAL BACKING IN RESPONSE TO
SOME PERTURBATION WITHIN THE FLOW...IT APPEARS THE CONDITIONAL
TORNADO THREAT WILL BE LIMITED TO THE SOUTHERN COASTAL PLAIN THROUGH
EARLY AFTERNOON.
CHANGES TO THE FORECAST ARE MOSTLY COSMETIC BASED ON TRENDS ON RADAR
AND OBS....WITH THE MAIN ADJUSTMENT TO THE NEAR TERM TEMPS AS
WARMING FROM THE TRIANGLE WESTWARD HAS BEEN A LITTLE SLOWER THAN
FORECAST. LATEST HRRR...WHICH HAS DONE A PRETTY GOOD JOB SO
FAR...SUGGESTS THE WEDGE MAY NOT BREAK IN THE FAR NORTHWEST PIEDMONT
UNTIL THE COLD FRONT ERODES THE AIRMASS LATER TONIGHT. HIGHS
ULTIMATELY END UP RANGING FROM 54-71 NORTHWEST TO SOUTHEAST. -BLS
PRECIP TONIGHT: PRECIPITATION MAY RE-DEVELOP IN THE FORM OF A NARROW
CONVECTIVE LINE LATER THIS EVENING (ROUGHLY 00-06Z) AS THE SFC COLD
FRONT SURGES EASTWARD THROUGH CENTRAL NC. CONFIDENCE IS LOWER THAN
NORMAL WITH REGARD TO THE EVOLUTION OF PRECIPITATION ALONG THE COLD
FRONT THIS EVENING...PARTICULARLY WITH REGARD TO PRE-FRONTAL THERMAL
PROFILES /INSTABILITY/ DUE TO THE WIDE VARIETY OF MECHANISMS AND
POSSIBLE INTERACTIONS DRIVING THE EVOLUTION THEREOF. BASED ON
PREVIOUS EXPERIENCE WITH SIMILAR SETUPS AND THE LATEST MODEL
GUIDANCE...EXPECT THE BEST POTENTIAL FOR ADDITIONAL PRECIPITATION
ALONG AND EAST OF HWY 1 IN THE 01-07Z TIME FRAME. FOR EXAMPLE...THE
HIGH-RES WRF-ARW SUGGESTS DRY CONDITIONS IN THE WESTERN PIEDMONT
WITH A NARROW LINE OF CONVECTION DEVELOPING IN VICINITY OF THE
TRIANGLE AROUND MIDNIGHT...EXITING THE COASTAL PLAIN BY 2-3 AM THU
MORNING.
WHETHER OR NOT CONVECTION WILL ACCOMPANY THE COLD FRONTAL PASSAGE
LATE THIS EVENING INTO TONIGHT ALSO REMAINS UNCLEAR. THE 00Z WRF-ARW
SUGGESTS THAT CONVECTION WILL DEVELOP ALONG THE FRONT AS IT
PROGRESSES FROM THE TRIANGLE INTO THE COASTAL PLAIN BETWEEN 01-07Z.
AN ISOLD SEVERE STORM CAPABLE OF PRODUCING DAMAGING WINDS CANNOT BE
RULED OUT IN THAT TIME FRAME...SHOULD CONVECTION DEVELOP. -VINCENT
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 255 AM WEDNESDAY...
THERE MAY BE A FEW SHOWERS IN THE PROCESS OF EXITING THE FAR EASTERN
ZONES CHRISTMAS MORNING... OTHERWISE EXPECT A WEST TO EAST CLEARING
TRENDING IN THE WAKE OF THE EXITING COLD FRONT.
ADDITIONALLY...DEEPENING SURFACE LOW LIFTING NEWD INTO SE CANADA
WILL RESULT IN BREEZY CONDITIONS ON CHRISTMAS DAY...WITH WEST-
NORTHWESTERLY WINDS GUSTING INTO THE UPPER TEENS TO LOWER
20S...STRONGEST DURING THE FIRST HALF OF THE DAY. WEAK CAA BEHIND
THE FRONT WILL STILL ALLOW FOR SEASONABLY MILD TEMPERATURES. HIGHS
IN THE MID 50S NW TO LOWER 60S SE. LOWS IN THE LOWER TO MID 30S.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 255 AM WEDNESDAY...
SATURDAY NIGHT INTO MONDAY...A PATTERN CHANGE WILL BEGIN TO OCCUR AS
THE UPPER RIDGE OVER THE SE STATES BREAKS DOWN AND A LARGE MID/UPPER
TROUGH DEVELOPS INTO THE WEST-CENTRAL THEN CENTRAL STATES. THE LEAD
COLD FRONT IS EXPECTED TO PUSH INTO NC FROM THE NORTH LATE SUNDAY OR
SUNDAY NIGHT. ALL BETS ARE OFF ON HOW FAR SOUTH THIS INITIAL FRONT
WILL BE ABLE TO SAG INTO NC OR SC. ABOUT HALF THE GFS ENSEMBLE
MEMBERS SUPPORT A STRONG ENOUGH SURFACE HIGH OVER A FAVORED GREAT
LAKES LOCATION TO PUSH THE FRONT INTO SC. THIS IS NOT SUPPORTED BY
THE LATEST OPERATIONAL EC AND HALF THE RELATED ENSEMBLES. THE
STRENGTH OF THE SURFACE WAVE SLATED TO DEVELOP OVER THE LOWER
MISSISSIPPI VALLEY AND THE SUBSEQUENT TRACK (EITHER JUST TO OUR WEST
AND NORTH... OR VERY NEAR OR OVER OUR REGION) IS ALSO CURRENTLY
DEBATABLE. WPC HAS SPLIT THE MIDDLE TAKING THE AVERAGE APPROACH
WHICH WOULD KEEP MOST OF OUR REGION IN THE WARM SECTOR INITIALLY
(UNTIL THE INITIAL WAVE OF LOW PRESSURE PASSES). THIS WOULD ENSURE
ALL RAIN AND MILDER TEMPERATURES THAN IF CAD WERE TO DEVELOP PER
SOME OF THE GFS MEMBERS. FOR NOW... WE WILL TREND A BIT COOLER AND
WETTER... AND TOWARD THE COOLER SOLUTIONS AND GIVE IT A FEW MORE
RUNS BEFORE COMMITTING EITHER WAY. THIS WOULD LEAD TO A CHANCE OF
RAIN LATE SUNDAY INTO MONDAY WITH LOWS IN THE MID 30S TO MID 40S AND
HIGHS IN THE MID 40S TO LOWER 60S N TO SE.
A TURN TO SHARPLY COLDER WEATHER IS EXPECTED BY MID NEXT WEEK WITH
LOWS BACK INTO THE 20S AND HIGHS IN THE 40S.
&&
.AVIATION /18Z WEDNESDAY THROUGH SUNDAY/...
AS OF 1210 PM WEDNESDAY...
PRIMARY AVIATION CONCERNS THIS PERIOD: IFR/LIFR CONDITIONS THROUGH
THIS EVENING... AND LOW LEVEL WIND SHEAR POTENTIAL THROUGH THIS
AFTERNOON.
PERIODS OF POOR AVIATION CONDITIONS WILL DOMINATE THROUGH THIS
EVENING. A WARM FRONT ORIENTED ROUGHLY NE TO SW THROUGH CENTRAL NC
WILL PUSH SLOWLY WNW TODAY THROUGH THIS EVENING... BEFORE A COLD
FRONT SWEEPS IN FROM THE WEST FROM LATE EVENING THROUGH THE
OVERNIGHT HOURS. THE WARM FRONT HAS ALREADY PUSHED WEST OF
FAY/RWI... WHERE SURFACE WINDS ARE MAINLY FROM THE SSW... AND THE
FRONT SHOULD MOVE THROUGH RDU THIS AFTERNOON. AT THESE LOCATIONS
(RDU/FAY/RWI)... VSBYS/CIGS WILL WAVER BETWEEN IFR/LIFR AND MVFR
THROUGH MIDNIGHT... WITH HIGH UNCERTAINTY AS TO WHICH CATEGORY WILL
DOMINATE. AT INT/GSO... THERE IS A GOOD CHANCE THE WARM FRONT WILL
NOT REACH THESE SITES... SO EXPECT THESE IFR/LIFR CONDITIONS TO
DOMINATE NEARLY CONTINUOUSLY THROUGH MID-LATE EVENING. STRONG WINDS
FROM THE SSW AT 30-50 KTS IN THE 800-1600 FT LAYER WILL BRING A RISK
OF LOW LEVEL WIND SHEAR THROUGH THIS AFTERNOON... WITH THE HIGHEST
LLWS POTENTIAL AT RDU WHERE THE VECTOR WIND DIFFERENCE BETWEEN THE
SURFACE AND AROUND 1000 FT AGL WILL BE GREATEST. COLD FRONT PASSAGE
THIS EVENING INTO THE OVERNIGHT HOURS WILL MEAN A RAPID W-TO-E TREND
OF CIGS FROM MAINLY IFR/LIFR TO VFR... MOST LIKELY AT INT/GSO
BETWEEN 02Z AND 04Z AND AT RDU/FAY/RWI BETWEEN 04Z AND 07Z... WITH A
SHIFT OF WINDS TO WSW THEN WNW. VFR CONDITIONS WILL THEN DOMINATE
FROM LATE TONIGHT THROUGH THE END OF THE TAF VALID PERIOD... AS HIGH
PRESSURE BUILDS IN FROM THE SW.
LOOKING BEYOND 18Z THU... VFR CONDITIONS ARE EXPECTED TO HOLD FROM
CHRISTMAS AFTERNOON INTO SUNDAY... ALTHOUGH SOME GROUND FOG IS
POSSIBLE EARLY SAT MORNING AT ALL CENTRAL NC TAF SITES. A STORM
SYSTEM WILL APPROACH FROM THE WEST AND SW ON SUN... BRINGING
INCREASING CHANCES FOR SUB-VFR CONDITIONS AND RAIN FOR LATE SUN
THROUGH MON. -GIH
&&
.HYDROLOGIC DISCUSSION /THROUGH THURSDAY/...
AS OF 210 PM TUESDAY...
THERE HAVE BEEN THREE FAIRLY SIGNIFICANT RAINFALL EVENTS OVER
CENTRAL NORTH CAROLINA DURING THE PAST TWO WEEKS...WITH HEAVIER
RAINFALL AMOUNTS (>1 INCH TOTAL) GENERALLY FROM THE TRIANGLE AND
FAYETTEVILLE AREAS EAST TO THE COAST. AS A RESULT...RELATIVE SOIL
MOISTURE IS UNIFORMLY HIGH THROUGH A 200 CM DEEP COLUMN...WHICH WILL
PROMOTE FASTER RUNOFF AS WELL AS A HIGHER PERCENTAGE OF RAINFALL-TO-
RUNOFF FROM THE UPCOMING EVENT TONIGHT THROUGH CHRISTMAS MORNING.
CURRENT QUANTITATIVE PRECIPITATION FORECASTS RANGE FROM 1.25 INCHES
TO NEARLY 2 INCHES...AND HAVE BEEN TRENDING DOWNWARD WITH SUCCESSIVE
MODEL RUNS. AT THIS TIME...OUR PREFERRED RAINFALL FORECAST IS FOR
WIDESPREAD AMOUNTS OF LESS THAN 1.5 INCHES...WHICH WILL CAUSE
MAINSTEM RIVERS TO RISE SEVERAL FEET FROM CHRISTMAS DAY INTO THE
WEEKEND...BUT RIVER FORECAST POINTS WOULD CREST BELOW MINOR FLOOD
STAGE. WIDESPREAD RAIN NEARER THE HIGH END OF THIS RANGE (1.75 TO
2 INCHES) WOULD LIKELY PRODUCE MINOR FLOODING ON EASTERN RIVERS...
PARTICULARLY THE HAW...NEUSE...AND TAR RIVERS.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT/BLS
SHORT TERM...BADGETT
LONG TERM...BADGETT
AVIATION...HARTFIELD
HYDROLOGY...BADGETT
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1151 AM EST WED DEC 24 2014
.SYNOPSIS...
LOW PRESSURE TO THE WEST OF THE APPALACHIANS WILL DEEPEN AND LIFT
NORTH TOWARD THE GREAT LAKES TODAY. THIS LOW WILL DRAG A COLD FRONT
THROUGH THE COASTAL CAROLINAS TONIGHT. DRY HIGH PRESSURE
WILL BUILD OVER THE SOUTHEAST CHRISTMAS DAY INTO FRIDAY BEFORE
MOVING OFF THE COAST SATURDAY. A COLD FRONT WILL DROP INTO THE
SOUTHEAST ON SUNDAY WITH A FEW WAVES OF LOW PRESSURE DEVELOPING
MONDAY THROUGH WEDNESDAY NEXT WEEK...LEAVING UNSETTLED WEATHER
ACROSS THE CAROLINAS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM WEDNESDAY...COMPLEX AND ACTIVE WEATHER ON TAP FOR MUCH
OF THE SOUTHEAST ON THIS CHRISTMAS EVE.
FULL LATITUDE UPPER TROUGH ALIGNED FROM THE WESTERN GREAT LAKES DOWN
INTO EASTERN TEXAS IS SLOWLY DRIFTING EAST THIS MORNING. BENEATH
THIS TROUGH...A STRENGTHENING SURFACE LOW IS MOVING NORTH INTO THE
GREAT LAKES...AND ALTHOUGH THIS WILL STAY WELL AWAY FROM THE
CWA...IT WILL DRIVE A STRONG COLD FRONT ACROSS THE REGION TONIGHT.
THE COMBINATION OF WAA AHEAD OF THE COLD FRONT...INCREASING THETA-E
RIDGING...AND DIFFLUENCE WITHIN AN UPPER JET WILL CREATE WIDESPREAD
SHOWERS WITH ISOLATED TSTMS TODAY. WHILE PRECIP WILL BE WIDESPREAD
AND HEAVY AT TIMES...TWO BIG QUESTION MARKS STILL REMAIN...AND THESE
ARE WHETHER SEVERE THUNDERSTORMS WILL DEVELOP...AND AT WHAT TIME THE
PRECIP WILL END TODAY.
KLTX IMAGERY THIS MORNING SHOWS AN AREA OF HEAVIER RAINFALL MOVING
ACROSS THE ILM NC COUNTIES...WITH SCATTERED BUT LESS INTENSE SHOWER
ACTIVITY TO THE SOUTHWEST. REGIONAL MOSAIC HAS A LINE OF CONVECTION
FROM WEST OF COLUMBIA, SC...TO VALDOSTA, GA. HIGH RES HRRR AND WRF
SUGGEST A LULL IN PRECIP FOR SEVERAL HOURS THIS AFTN AHEAD OF THE
FORCED LINE...AND HAVE TRIED TO SHOW POP TRENDS MIMICKING THIS IDEA.
THIS SEEMS PLAUSIBLE SINCE DIFFLUENCE THIS MORNING WILL WEAKEN AND
SOME SUBSIDENCE IS LIKELY IN THE WAKE OF THIS MORNINGS ACTION.
HOWEVER...ISOLATED THUNDER WILL STILL BE POSSIBLE THROUGH NOON OR
SO...ESPECIALLY IN PLACES WHERE TEMPS HIT 70-72F SINCE THAT WILL BE
CAPABLE OF TAPPING THE INSTABILITY ABOVE 950MB PRESENT ON THE 12Z
KCHS UA SOUNDING. HEAVY RAIN WILL BE THE PRIMARY THREAT THIS
MORNING...AND SOME PLACES MAY PICK UP A QUICK 1 INCH OF QPF IN
EMBEDDED TSTMS.
THEREAFTER...ATTN TURNS TO THE PRE-FRONTAL FORCED LINE AND ITS
ANTICIPATED IMPACTS LOCALLY. AS THE LOW PRESSURE MOVES NORTH...THE
EASTWARD PROGRESS OF THIS LINE WILL SLOW...AND THEREFORE BELIEVE THE
WRF IS TOO FAST IN ITS EVOLUTION...BUT STILL ACCURATE IN ITS OVERALL
DEPICTION. SPC SWODY1 HAS THE AREA IN A MARGINAL RISK...WITH A
SLIGHT RISK SOUTH OF MYRTLE BEACH...FOR POSSIBLE DAMAGING WINDS AND
ISOLATED TORNADOES AS THIS QLCS APPROACHES. LOCALLY THE TORNADO
THREAT SEEMS EXTREMELY LOW WITH MLCAPES OF 300 J/KG OR LESS AND
0-3KM SRH REACHING ONLY AS HIGH AS AROUND 200 M2/S2. AT THE SAME
TIME...LOW-LEVEL WINDS OF 50 KTS AT 2KFT WILL SLOWLY VEER MORE TO
THE SW THIS AFTN...ERODING EVEN FURTHER THE TORNADO THREAT...BUT
MAINTAINING A DAMAGING WIND POTENTIAL. WILL HAVE TO MONITOR
EVOLUTION OF THIS SQUALL LINE AS IT REACHES THE CWA...AND IT WILL
LIKELY DO SO IN A WEAKENING STATE...BUT CANNOT RULE OUT AN ISOLATED
DAMAGING WIND GUST THIS EVENING. A LARGE AREA OF TRAILING STRATIFORM
RAIN WILL PERSIST BEHIND THE SQUALL LINE...AND THUS EVEN THOUGH THE
COLD FRONT DOES NOT CROSS THE CWA UNTIL AFTER MIDNIGHT...IT WILL
HAVE DIFFICULTY DEVELOPING ANY CONVECTION OTHER THAN SHALLOW SHOWERY
TYPE PRECIP.
HIGHS TODAY WILL RISE INTO THE LOW 70S MOST AREAS EVEN WITHOUT ANY
SUNSHINE THANKS TO STRONG WAA. TEMPERATURES WILL BEGIN TO CRASH
BEHIND THE COLD FRONT AFTER MIDNIGHT...BUT ONLY A FEW HOURS OF
COOLING BEFORE DAYBREAK WILL LIMIT MINS TO AROUND 50 WELL
INLAND...AND NEAR 60 RIGHT ALONG THE COAST.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 AM WEDNESDAY...A COLD FRONT WILL BE PUSHING FARTHER OFF
SHORE THROUGH THURS AS HIGH PRESSURE BUILDS UP FROM GULF COAST.
ANY LINGERING PCP OR MOISTURE WILL BE SCOURED OUT AS MID TO UPPER
TROUGH MOVES EAST LEAVING A DEEP DRY AND COOLER W-NW FLOW BEHIND
IT. EXPECT PCP WATER VALUES DOWN FROM UP NEAR 2 INCHES THE NIGHT
BEFORE TO A QUARTER OF INCH BY THURS AFTERNOON AS COLUMN DRIES
OUT. OVERALL EXPECT CLEARING SKIES ON CHRISTMAS DAY WITH SUNSHINE
MAKING AN APPEARANCE FOR THE FIRST TIME IN SEVERAL DAYS. TEMPS
SHOULD NOT MOVE MUCH ON THURS AS A WARM START TO THE DAY WILL BE
FOLLOWED BY GUSTY W-NW WINDS BRINGING IN RELATIVELY COOLER AIR.
MODELS HAVE BEEN CONSISTENTLY BACKING OFF ON CAA BEHIND THE FRONT
WITH 850 TEMPS ONLY FALLING ABOUT 6 C BEHIND FRONT BEFORE LEVELING
OFF AND RISING SLIGHTLY THROUGH FRI. TEMPS THURS NIGHT SHOULD BE
DOWN IN THE 30S AND BASICALLY EXPECT SEASONABLE TO ABOVE NORMAL
TEMPS IN THE FORECAST AS HIGH PRESSURE BUILDS UP FROM THE GULF
COAST OVER THE SOUTHEAST THROUGH FRI.
THE CENTER OF THE HIGH ALMOST DIRECTLY OVERHEAD FRI AFTN WILL
SHIFT OFF SHORE BY FRI NIGHT LEAVING A LIGHT RETURN FLOW. THIS
WILL HELP TO CAUSE A SLIGHT RISE IN DEWPOINT TEMPS AND THEREFORE
WILL KEEP TEMP A BIT HIGHER THAN THE NIGHT BEFORE BUT THE WINDS
WILL BE LIGHT ENOUGH UNDER CLEAR SKIES TO PRODUCE DECENT
RADIATIONAL COOLING. THIS WILL BRING TEMPS DOWN CLOSER TO 40 FOR
FRI NIGHT.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 330 AM WEDNESDAY...RIDGE OF HIGH PRESSURE UP THE SOUTHEAST
COAST ON SATURDAY WILL SHIFT EAST THROUGH EARLY NEXT WEEK. THIS
WILL ALLOW A RETURN FLOW TO SET UP WITH SW-W WINDS THROUGH THE
LOW TO MID LEVELS OF THE ATMOSPHERE. INITIALLY SHOULD SEE A FAIR
AMOUNT OF SUNSHINE ON SATURDAY BUT A COLD FRONT WILL DROP SOUTH ON
SUNDAY LEAVING SHALLOW COOL AIR IN PLACE. SHOULD SEE CLOUDS AND
PCP SPREAD OVER THE CAROLINAS SAT NIGHT INTO SUNDAY AS COLD FRONT
DROPS SOUTH WITH SOME DECENT ISENTROPIC LIFT DEVELOPING. THE GFS
AND ECMWF SHOW A FEW WAVES OF LOW PRESSURE MOVING UP FROM THE
GULF COAST ALONG THIS FRONT THROUGH NEXT WEEK. MAY END UP WITH AN
EXTENDED PERIOD OF UNSETTLED WEATHER AS POSSIBLE WEDGE SETS UP.
TEMPS ON SAT INTO SUNDAY SHOULD REMAIN ON THE WARM SIDE WITH 60S
MOST PLACES. SOME UNCERTAINTY EXISTS WITH LOCATION OF COLD FRONT
AS ECMWF KEEPS IT NORTH AND SHOWS WAVES OF LOW PRESSURE MOVING
ALONG FRONT TO THE NORTH OF LOCAL AREA. THIS COULD KEEP LOCAL AREA
IN WARMER SW FLOW AT THE SURFACE WITH WEDGE HOLDING INLAND AND TO
OUR NORTH.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 18Z...MODERATE TO HEAVY PRECIP WILL OCCUR THROUGH MUCH OF THE
AFTERNOON WITH ISOLATED THUNDER. THE COASTAL TERMINALS ARE BOUNCING
FROM IFR TO MVFR WITH STRONG SOUTH SOUTHWESTERLY FLOW. MODELS ARE IN
REASONABLE AGREEMENT WITH THE HEAVIEST ACTIVITY THIS
AFTERNOON...FOLLOWED BY LIGHTER PRECIP ALONG THE FRONT THIS EVENING.
THE FRONT WILL REACH THE COAST THROUGH THE OVERNIGHT HOURS. LOOK FOR
A WIND SHIFT TO THE WEST...POST FRONTAL. SKIES SHOULD IMPROVE FAIRLY
RAPIDLY TO VFR BEHIND THE FRONT WITH GUSTY WEST WINDS DIMINISHING
SOMEWHAT SHORTLY AFTER DAYBREAK.
EXTENDED OUTLOOK...VFR THURSDAY THROUGH SATURDAY. RAIN RETURNING
SUNDAY AND POSSIBLY MONDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM WEDNESDAY...TROPICAL AIRMASS BEHIND A WARM FRONT NOW
SITUATED WELL INLAND IS ADVECTING INTO THE WATERS THIS
MORNING...WITH DEWPOINT TEMPERATURES APPROACHING 70...OR EVEN THE
LOW 70S. THESE DEWPOINT TEMPS ARE 15 DEGREES ABOVE THE COOL SHELF
WATER TEMPS...WHICH IS TYPICALLY A SIGNAL FOR SEA FOG. ATTM
HOWEVER...NO VSBY RESTRICTIONS HAVE BEEN NOTED AND IT MAY BE SIMPLY
DUE TO THE STRENGTH OF THE WIND FIELDS NOT ALLOWING FOR AMPLE PARCEL
RESIDENCE TIME. STILL...THE MARINE DENSE FOG ADVISORY REMAINS AND
WILL CONTINUE AS THERE REDUCED VISIBILITY IN MARINE FOG IS STILL
EXPECTED TO DEVELOP UNTIL THE COLD FRONTAL PASSAGE TONIGHT.
SHOWER ACTIVITY WILL BE SCATTERED THROUGH THE AFTN AND EVE...BEFORE
A MORE STRONGLY FORCED SQUALL LINE WILL CROSS THE WATERS THIS
EVENING AND TONIGHT. WINDS WILL BE GUSTY TODAY EVEN OUTSIDE OF
CONVECTION...AND THE CURRENT SCA REMAINS UNCHANGED FOR BOTH WINDS
AND SEAS...WHICH ARE ALREADY APPROACHING 7 FT AT WILMINGTON HARBOR
BUOY. A WIND SHIFT TO THE WEST WILL OCCUR WITH THE FROPA...WHICH IS
EXPECTED AFTER MIDNIGHT.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 AM WEDNESDAY...COLD FRONT WILL SHIFT FARTHER OFF SHORE ON
THURS AS HIGH PRESSURE BUILDS UP FROM THE GULF COAST. GUSTY W-SW
WINDS EARLY THURS WILL VEER AROUND BECOMING WEST THROUGH THE DAY.
SEAS UP AROUND 5 TO 7 FT SHOULD FALL BELOW SCA THRESHOLDS BY THURS
AFTN WITH HIGHEST SEAS GETTING PUSHED FARTHER OFF SHORE IN STRONGER
W-NW FLOW BEHIND FRONT. WINDS WILL VEER FURTHER TO THE NW AND
LIGHTEN UP LATE THURS INTO FRI AS CENTER OF HIGH SHIFTS CLOSER
OVERHEAD. SEAS WILL BE DOWN TO 2 TO 4 FT BY THURS NIGHT AND DOWN TO
3 FT OR LESS THROUGH FRI AS HIGH PRESSURE MOVES OVERHEAD WITH MORE
VARIABLE WINDS EXPECTED.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 330 AM WEDNESDAY...HIGH PRESSURE WILL SHIFT FARTHER OFF
SHORE ON SATURDAY WITH A RETURN FLOW S-SW 10 KTS OR LESS SETTING
UP. A COLD FRONT WILL DROP SOUTH SUN WITH POSSIBLE WEDGE
DEVELOPING WITH WINDS VEERING AROUND TO THE N-NE AS IT DROPS SOUTH
SUN NIGHT. THIS WILL PUSH SEAS UP A BIT BUT OVERALL BUT EXPECT
SEAS TO GENERALLY 3 FT OR LESS THROUGH THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...DENSE FOG ADVISORY UNTIL 6 PM EST THIS EVENING FOR AMZ250-252-
254-256.
SMALL CRAFT ADVISORY UNTIL NOON EST THURSDAY FOR AMZ250-252-
254-256.
&&
$$
NEAR TERM...17
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...43
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1050 AM EST WED DEC 24 2014
.SYNOPSIS...A WARM FRONT WILL LIFT NORTHWARD THROUGH THE CAROLINAS
TODAY AS A DEEPENING LOW PRESSURE SYSTEM TRACKS INTO THE TENNESSEE
VALLEY. A COLD FRONT WILL SURGE EAST ACROSS THE REGION TONIGHT AS
THE SURFACE LOW PROGRESSES NORTHWARD THROUGH THE OHIO VALLEY INTO
THE GREAT LAKES.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 1050 AM WEDNESDAY...
LARGE WARM CONVEYOR BELT PRECIP SHIELD STRETCHES FROM THE MID-
ATLANTIC COAST TO THE GULF OF MEXICO...WITH AN EMBEDDED QLCS FROM
SOUTH CAROLINA THROUGH THE FLORIDA PANHANDLE. MEANWHILE...THE WEDGE
AND COASTAL FRONTS CONTINUE THEIR RETREAT THROUGH THE COASTAL PLAIN
AND INTO THE PIEDMONT THIS MORNING...LEADING TO A STRONG BAROCLINIC
ZONE JUST EAST OF THE US-1 CORRIDOR. TEMPS ARE STILL IN THE MID 40S
NORTHWEST TO NOW UPPER 60S SOUTHEAST. THE BULK OF THE PRECIP WILL
CONTINUE TO SHIFT EAST THROUGH EARLY AFTERNOON IN CONCERT WITH THE
LOW-LEVEL JET....WITH SOME ENHANCEMENT ALONG THE AFOREMENTIONED
FRONTAL ZONE. A LULL IN PRECIP IS ANTICIPATED THIS AFTERNOON ON THE
HEELS OF THE LOW-LEVEL JET...WITH FORCING SOMEWHAT LIMITED GIVEN
THAT THE POSITIVELY TILTED UPPER TROUGH OVER THE MISSISSIPPI RIVER
VALLEY DOESNT MAKE ITS STRONG EASTWARD PUSH UNTIL TONIGHT. MOST OF
THE CAM`S SUPPORT THIS IDEA...WITH JUST ISOLATED TO WIDELY SCATTERED
SHOWERS AFTER 18Z. THE THREAT OF AN SEVERE WEATHER SHOULD REMAIN
CONFINED TO THE COASTAL PLAIN...WHERE MARGINAL CAPE AND STRONG
SHEAR PHASE THIS AFTERNOON. MODIFIED RAP SOUNDINGS SUGGEST 200-300
J/KG MLCAPE EAST OF I-95 IN THE TRUER WARM SECTOR... WITH 50-60KT
BULK SHEAR. HOWEVER...LOW-LEVEL HODOGRAPHS WILL BECOME MORE LINEAR
WITH TIME AS THE SURFACE WINDS CONTINUE TO VEER TO MORE
SOUTHWESTERLY....SO UNLESS THERE IS LOCAL BACKING IN RESPONSE TO
SOME PERTURBATION WITHIN THE FLOW...IT APPEARS THE CONDITIONAL
TORNADO THREAT WILL BE LIMITED TO THE SOUTHERN COASTAL PLAIN THROUGH
EARLY AFTERNOON.
CHANGES TO THE FORECAST ARE MOSTLY COSMETIC BASED ON TRENDS ON RADAR
AND OBS....WITH THE MAIN ADJUSTMENT TO THE NEAR TERM TEMPS AS
WARMING FROM THE TRIANGLE WESTWARD HAS BEEN A LITTLE SLOWER THAN
FORECAST. LATEST HRRR...WHICH HAS DONE A PRETTY GOOD JOB SO
FAR...SUGGESTS THE WEDGE MAY NOT BREAK IN THE FAR NORTHWEST PIEDMONT
UNTIL THE COLD FRONT ERODES THE AIRMASS LATER TONIGHT. HIGHS
ULTIMATELY END UP RANGING FROM 54-71 NORTHWEST TO SOUTHEAST. -BLS
PRECIP TONIGHT: PRECIPITATION MAY RE-DEVELOP IN THE FORM OF A NARROW
CONVECTIVE LINE LATER THIS EVENING (ROUGHLY 00-06Z) AS THE SFC COLD
FRONT SURGES EASTWARD THROUGH CENTRAL NC. CONFIDENCE IS LOWER THAN
NORMAL WITH REGARD TO THE EVOLUTION OF PRECIPITATION ALONG THE COLD
FRONT THIS EVENING...PARTICULARLY WITH REGARD TO PRE-FRONTAL THERMAL
PROFILES /INSTABILITY/ DUE TO THE WIDE VARIETY OF MECHANISMS AND
POSSIBLE INTERACTIONS DRIVING THE EVOLUTION THEREOF. BASED ON
PREVIOUS EXPERIENCE WITH SIMILAR SETUPS AND THE LATEST MODEL
GUIDANCE...EXPECT THE BEST POTENTIAL FOR ADDITIONAL PRECIPITATION
ALONG AND EAST OF HWY 1 IN THE 01-07Z TIME FRAME. FOR EXAMPLE...THE
HIGH-RES WRF-ARW SUGGESTS DRY CONDITIONS IN THE WESTERN PIEDMONT
WITH A NARROW LINE OF CONVECTION DEVELOPING IN VICINITY OF THE
TRIANGLE AROUND MIDNIGHT...EXITING THE COASTAL PLAIN BY 2-3 AM THU
MORNING.
WHETHER OR NOT CONVECTION WILL ACCOMPANY THE COLD FRONTAL PASSAGE
LATE THIS EVENING INTO TONIGHT ALSO REMAINS UNCLEAR. THE 00Z WRF-ARW
SUGGESTS THAT CONVECTION WILL DEVELOP ALONG THE FRONT AS IT
PROGRESSES FROM THE TRIANGLE INTO THE COASTAL PLAIN BETWEEN 01-07Z.
AN ISOLD SEVERE STORM CAPABLE OF PRODUCING DAMAGING WINDS CANNOT BE
RULED OUT IN THAT TIME FRAME...SHOULD CONVECTION DEVELOP. -VINCENT
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 255 AM WEDNESDAY...
THERE MAY BE A FEW SHOWERS IN THE PROCESS OF EXITING THE FAR EASTERN
ZONES CHRISTMAS MORNING... OTHERWISE EXPECT A WEST TO EAST CLEARING
TRENDING IN THE WAKE OF THE EXITING COLD FRONT.
ADDITIONALLY...DEEPENING SURFACE LOW LIFTING NEWD INTO SE CANADA
WILL RESULT IN BREEZY CONDITIONS ON CHRISTMAS DAY...WITH WEST-
NORTHWESTERLY WINDS GUSTING INTO THE UPPER TEENS TO LOWER
20S...STRONGEST DURING THE FIRST HALF OF THE DAY. WEAK CAA BEHIND
THE FRONT WILL STILL ALLOW FOR SEASONABLY MILD TEMPERATURES. HIGHS
IN THE MID 50S NW TO LOWER 60S SE. LOWS IN THE LOWER TO MID 30S.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 255 AM WEDNESDAY...
SATURDAY NIGHT INTO MONDAY...A PATTERN CHANGE WILL BEGIN TO OCCUR AS
THE UPPER RIDGE OVER THE SE STATES BREAKS DOWN AND A LARGE MID/UPPER
TROUGH DEVELOPS INTO THE WEST-CENTRAL THEN CENTRAL STATES. THE LEAD
COLD FRONT IS EXPECTED TO PUSH INTO NC FROM THE NORTH LATE SUNDAY OR
SUNDAY NIGHT. ALL BETS ARE OFF ON HOW FAR SOUTH THIS INITIAL FRONT
WILL BE ABLE TO SAG INTO NC OR SC. ABOUT HALF THE GFS ENSEMBLE
MEMBERS SUPPORT A STRONG ENOUGH SURFACE HIGH OVER A FAVORED GREAT
LAKES LOCATION TO PUSH THE FRONT INTO SC. THIS IS NOT SUPPORTED BY
THE LATEST OPERATIONAL EC AND HALF THE RELATED ENSEMBLES. THE
STRENGTH OF THE SURFACE WAVE SLATED TO DEVELOP OVER THE LOWER
MISSISSIPPI VALLEY AND THE SUBSEQUENT TRACK (EITHER JUST TO OUR WEST
AND NORTH... OR VERY NEAR OR OVER OUR REGION) IS ALSO CURRENTLY
DEBATABLE. WPC HAS SPLIT THE MIDDLE TAKING THE AVERAGE APPROACH
WHICH WOULD KEEP MOST OF OUR REGION IN THE WARM SECTOR INITIALLY
(UNTIL THE INITIAL WAVE OF LOW PRESSURE PASSES). THIS WOULD ENSURE
ALL RAIN AND MILDER TEMPERATURES THAN IF CAD WERE TO DEVELOP PER
SOME OF THE GFS MEMBERS. FOR NOW... WE WILL TREND A BIT COOLER AND
WETTER... AND TOWARD THE COOLER SOLUTIONS AND GIVE IT A FEW MORE
RUNS BEFORE COMMITTING EITHER WAY. THIS WOULD LEAD TO A CHANCE OF
RAIN LATE SUNDAY INTO MONDAY WITH LOWS IN THE MID 30S TO MID 40S AND
HIGHS IN THE MID 40S TO LOWER 60S N TO SE.
A TURN TO SHARPLY COLDER WEATHER IS EXPECTED BY MID NEXT WEEK WITH
LOWS BACK INTO THE 20S AND HIGHS IN THE 40S.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AS OF 730 AM WEDNESDAY...
24-HR TAF PERIOD: LIFR CONDITIONS ASSOCIATED WITH A PRONOUNCED COLD
AIR DAMMING WEDGE WILL PERSIST OVER CENTRAL NORTH CAROLINA THIS
MORNING AS WIDESPREAD PRECIPITATION OVERSPREADS THE REGION FROM THE
SOUTH/SW. GRADUAL IMPROVEMENT TO IFR AND PERHAPS LOW-END MVFR IS
EXPECTED FROM SOUTH/SE TO NORTH/NW LATE THIS MORNING INTO THIS
AFTERNOON AS A WARM FRONT LIFTS NORTHWARD THROUGH CENTRAL NC...
EARLIEST AT THE FAY TERMINAL AND LATEST AT THE INT/GSO TERMINALS.
SOUTHERLY LOW LEVEL WIND SHEAR WILL LOWER IN ALTITUDE (FROM ~1500 FT
AGL TO 500 FT AGL) THROUGH NOON AS A LOW PRESSURE SYSTEM DEEPENS
WEST OF THE MOUNTAINS AND THE COLD AIR DAMMING WEDGE GRADUALLY
SHALLOWS/ERODES. LOW LEVEL WIND SHEAR WILL END BY EARLY AFTERNOON AS
THE CAD WEDGE DISSIPATES AND VERTICAL MIXING INCREASES. IFR OR LOW-
END MVFR CONDITIONS...A CHANCE FOR SHOWERS/STORMS...AND A SOUTHERLY
BREEZE WILL PREVAIL THIS AFTERNOON AND EVENING...IN ADVANCE OF A
COLD FRONT APPROACHING FROM THE WEST. VFR CONDITIONS WILL RETURN
FROM WEST-EAST BETWEEN MIDNIGHT AND SUNRISE THURSDAY AS BREEZY
WEST/NW WINDS ADVECT A DRIER AIRMASS INTO THE REGION IN THE WAKE OF
THE COLD FRONT.
LOOKING AHEAD: VFR CONDITIONS WILL PREVAIL THURSDAY INTO THE WEEKEND
IN ASSOCIATION WITH HIGH PRESSURE OVER THE REGION. -VINCENT
&&
.HYDROLOGIC DISCUSSION /THROUGH THURSDAY/...
AS OF 210 PM TUESDAY...
THERE HAVE BEEN THREE FAIRLY SIGNIFICANT RAINFALL EVENTS OVER
CENTRAL NORTH CAROLINA DURING THE PAST TWO WEEKS...WITH HEAVIER
RAINFALL AMOUNTS (>1 INCH TOTAL) GENERALLY FROM THE TRIANGLE AND
FAYETTEVILLE AREAS EAST TO THE COAST. AS A RESULT...RELATIVE SOIL
MOISTURE IS UNIFORMLY HIGH THROUGH A 200 CM DEEP COLUMN...WHICH WILL
PROMOTE FASTER RUNOFF AS WELL AS A HIGHER PERCENTAGE OF RAINFALL-TO-
RUNOFF FROM THE UPCOMING EVENT TONIGHT THROUGH CHRISTMAS MORNING.
CURRENT QUANTITATIVE PRECIPITATION FORECASTS RANGE FROM 1.25 INCHES
TO NEARLY 2 INCHES...AND HAVE BEEN TRENDING DOWNWARD WITH SUCCESSIVE
MODEL RUNS. AT THIS TIME...OUR PREFERRED RAINFALL FORECAST IS FOR
WIDESPREAD AMOUNTS OF LESS THAN 1.5 INCHES...WHICH WILL CAUSE
MAINSTEM RIVERS TO RISE SEVERAL FEET FROM CHRISTMAS DAY INTO THE
WEEKEND...BUT RIVER FORECAST POINTS WOULD CREST BELOW MINOR FLOOD
STAGE. WIDESPREAD RAIN NEARER THE HIGH END OF THIS RANGE (1.75 TO
2 INCHES) WOULD LIKELY PRODUCE MINOR FLOODING ON EASTERN RIVERS...
PARTICULARLY THE HAW...NEUSE...AND TAR RIVERS.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT/BLS
SHORT TERM...BADGETT
LONG TERM...BADGETT
AVIATION...VINCENT
HYDROLOGY...BADGETT
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1042 AM EST WED DEC 24 2014
.SYNOPSIS...
LOW PRESSURE TO THE WEST OF THE APPALACHIANS WILL DEEPEN AND LIFT
NORTH TOWARD THE GREAT LAKES TODAY. THIS LOW WILL DRAG A COLD FRONT
THROUGH THE COASTAL CAROLINAS TONIGHT. DRY HIGH PRESSURE
WILL BUILD OVER THE SOUTHEAST CHRISTMAS DAY INTO FRIDAY BEFORE
MOVING OFF THE COAST SATURDAY. A COLD FRONT WILL DROP INTO THE
SOUTHEAST ON SUNDAY WITH A FEW WAVES OF LOW PRESSURE DEVELOPING
MONDAY THROUGH WEDNESDAY NEXT WEEK...LEAVING UNSETTLED WEATHER
ACROSS THE CAROLINAS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM WEDNESDAY...COMPLEX AND ACTIVE WEATHER ON TAP FOR MUCH
OF THE SOUTHEAST ON THIS CHRISTMAS EVE.
FULL LATITUDE UPPER TROUGH ALIGNED FROM THE WESTERN GREAT LAKES DOWN
INTO EASTERN TEXAS IS SLOWLY DRIFTING EAST THIS MORNING. BENEATH
THIS TROUGH...A STRENGTHENING SURFACE LOW IS MOVING NORTH INTO THE
GREAT LAKES...AND ALTHOUGH THIS WILL STAY WELL AWAY FROM THE
CWA...IT WILL DRIVE A STRONG COLD FRONT ACROSS THE REGION TONIGHT.
THE COMBINATION OF WAA AHEAD OF THE COLD FRONT...INCREASING THETA-E
RIDGING...AND DIFFLUENCE WITHIN AN UPPER JET WILL CREATE WIDESPREAD
SHOWERS WITH ISOLATED TSTMS TODAY. WHILE PRECIP WILL BE WIDESPREAD
AND HEAVY AT TIMES...TWO BIG QUESTION MARKS STILL REMAIN...AND THESE
ARE WHETHER SEVERE THUNDERSTORMS WILL DEVELOP...AND AT WHAT TIME THE
PRECIP WILL END TODAY.
KLTX IMAGERY THIS MORNING SHOWS AN AREA OF HEAVIER RAINFALL MOVING
ACROSS THE ILM NC COUNTIES...WITH SCATTERED BUT LESS INTENSE SHOWER
ACTIVITY TO THE SOUTHWEST. REGIONAL MOSAIC HAS A LINE OF CONVECTION
FROM WEST OF COLUMBIA, SC...TO VALDOSTA, GA. HIGH RES HRRR AND WRF
SUGGEST A LULL IN PRECIP FOR SEVERAL HOURS THIS AFTN AHEAD OF THE
FORCED LINE...AND HAVE TRIED TO SHOW POP TRENDS MIMICKING THIS IDEA.
THIS SEEMS PLAUSIBLE SINCE DIFFLUENCE THIS MORNING WILL WEAKEN AND
SOME SUBSIDENCE IS LIKELY IN THE WAKE OF THIS MORNINGS ACTION.
HOWEVER...ISOLATED THUNDER WILL STILL BE POSSIBLE THROUGH NOON OR
SO...ESPECIALLY IN PLACES WHERE TEMPS HIT 70-72F SINCE THAT WILL BE
CAPABLE OF TAPPING THE INSTABILITY ABOVE 950MB PRESENT ON THE 12Z
KCHS UA SOUNDING. HEAVY RAIN WILL BE THE PRIMARY THREAT THIS
MORNING...AND SOME PLACES MAY PICK UP A QUICK 1 INCH OF QPF IN
EMBEDDED TSTMS.
THEREAFTER...ATTN TURNS TO THE PRE-FRONTAL FORCED LINE AND ITS
ANTICIPATED IMPACTS LOCALLY. AS THE LOW PRESSURE MOVES NORTH...THE
EASTWARD PROGRESS OF THIS LINE WILL SLOW...AND THEREFORE BELIEVE THE
WRF IS TOO FAST IN ITS EVOLUTION...BUT STILL ACCURATE IN ITS OVERALL
DEPICTION. SPC SWODY1 HAS THE AREA IN A MARGINAL RISK...WITH A
SLIGHT RISK SOUTH OF MYRTLE BEACH...FOR POSSIBLE DAMAGING WINDS AND
ISOLATED TORNADOES AS THIS QLCS APPROACHES. LOCALLY THE TORNADO
THREAT SEEMS EXTREMELY LOW WITH MLCAPES OF 300 J/KG OR LESS AND
0-3KM SRH REACHING ONLY AS HIGH AS AROUND 200 M2/S2. AT THE SAME
TIME...LOW-LEVEL WINDS OF 50 KTS AT 2KFT WILL SLOWLY VEER MORE TO
THE SW THIS AFTN...ERODING EVEN FURTHER THE TORNADO THREAT...BUT
MAINTAINING A DAMAGING WIND POTENTIAL. WILL HAVE TO MONITOR
EVOLUTION OF THIS SQUALL LINE AS IT REACHES THE CWA...AND IT WILL
LIKELY DO SO IN A WEAKENING STATE...BUT CANNOT RULE OUT AN ISOLATED
DAMAGING WIND GUST THIS EVENING. A LARGE AREA OF TRAILING STRATIFORM
RAIN WILL PERSIST BEHIND THE SQUALL LINE...AND THUS EVEN THOUGH THE
COLD FRONT DOES NOT CROSS THE CWA UNTIL AFTER MIDNIGHT...IT WILL
HAVE DIFFICULTY DEVELOPING ANY CONVECTION OTHER THAN SHALLOW SHOWERY
TYPE PRECIP.
HIGHS TODAY WILL RISE INTO THE LOW 70S MOST AREAS EVEN WITHOUT ANY
SUNSHINE THANKS TO STRONG WAA. TEMPERATURES WILL BEGIN TO CRASH
BEHIND THE COLD FRONT AFTER MIDNIGHT...BUT ONLY A FEW HOURS OF
COOLING BEFORE DAYBREAK WILL LIMIT MINS TO AROUND 50 WELL
INLAND...AND NEAR 60 RIGHT ALONG THE COAST.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 AM WEDNESDAY...A COLD FRONT WILL BE PUSHING FARTHER OFF
SHORE THROUGH THURS AS HIGH PRESSURE BUILDS UP FROM GULF COAST.
ANY LINGERING PCP OR MOISTURE WILL BE SCOURED OUT AS MID TO UPPER
TROUGH MOVES EAST LEAVING A DEEP DRY AND COOLER W-NW FLOW BEHIND
IT. EXPECT PCP WATER VALUES DOWN FROM UP NEAR 2 INCHES THE NIGHT
BEFORE TO A QUARTER OF INCH BY THURS AFTERNOON AS COLUMN DRIES
OUT. OVERALL EXPECT CLEARING SKIES ON CHRISTMAS DAY WITH SUNSHINE
MAKING AN APPEARANCE FOR THE FIRST TIME IN SEVERAL DAYS. TEMPS
SHOULD NOT MOVE MUCH ON THURS AS A WARM START TO THE DAY WILL BE
FOLLOWED BY GUSTY W-NW WINDS BRINGING IN RELATIVELY COOLER AIR.
MODELS HAVE BEEN CONSISTENTLY BACKING OFF ON CAA BEHIND THE FRONT
WITH 850 TEMPS ONLY FALLING ABOUT 6 C BEHIND FRONT BEFORE LEVELING
OFF AND RISING SLIGHTLY THROUGH FRI. TEMPS THURS NIGHT SHOULD BE
DOWN IN THE 30S AND BASICALLY EXPECT SEASONABLE TO ABOVE NORMAL
TEMPS IN THE FORECAST AS HIGH PRESSURE BUILDS UP FROM THE GULF
COAST OVER THE SOUTHEAST THROUGH FRI.
THE CENTER OF THE HIGH ALMOST DIRECTLY OVERHEAD FRI AFTN WILL
SHIFT OFF SHORE BY FRI NIGHT LEAVING A LIGHT RETURN FLOW. THIS
WILL HELP TO CAUSE A SLIGHT RISE IN DEWPOINT TEMPS AND THEREFORE
WILL KEEP TEMP A BIT HIGHER THAN THE NIGHT BEFORE BUT THE WINDS
WILL BE LIGHT ENOUGH UNDER CLEAR SKIES TO PRODUCE DECENT
RADIATIONAL COOLING. THIS WILL BRING TEMPS DOWN CLOSER TO 40 FOR
FRI NIGHT.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 330 AM WEDNESDAY...RIDGE OF HIGH PRESSURE UP THE SOUTHEAST
COAST ON SATURDAY WILL SHIFT EAST THROUGH EARLY NEXT WEEK. THIS
WILL ALLOW A RETURN FLOW TO SET UP WITH SW-W WINDS THROUGH THE
LOW TO MID LEVELS OF THE ATMOSPHERE. INITIALLY SHOULD SEE A FAIR
AMOUNT OF SUNSHINE ON SATURDAY BUT A COLD FRONT WILL DROP SOUTH ON
SUNDAY LEAVING SHALLOW COOL AIR IN PLACE. SHOULD SEE CLOUDS AND
PCP SPREAD OVER THE CAROLINAS SAT NIGHT INTO SUNDAY AS COLD FRONT
DROPS SOUTH WITH SOME DECENT ISENTROPIC LIFT DEVELOPING. THE GFS
AND ECMWF SHOW A FEW WAVES OF LOW PRESSURE MOVING UP FROM THE
GULF COAST ALONG THIS FRONT THROUGH NEXT WEEK. MAY END UP WITH AN
EXTENDED PERIOD OF UNSETTLED WEATHER AS POSSIBLE WEDGE SETS UP.
TEMPS ON SAT INTO SUNDAY SHOULD REMAIN ON THE WARM SIDE WITH 60S
MOST PLACES. SOME UNCERTAINTY EXISTS WITH LOCATION OF COLD FRONT
AS ECMWF KEEPS IT NORTH AND SHOWS WAVES OF LOW PRESSURE MOVING
ALONG FRONT TO THE NORTH OF LOCAL AREA. THIS COULD KEEP LOCAL AREA
IN WARMER SW FLOW AT THE SURFACE WITH WEDGE HOLDING INLAND AND TO
OUR NORTH.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AS OF 12Z...MODERATE SHOWERS ARE TRAINING OVER THE WESTERN PORTION
OF THE REGION...WITH ANOTHER SLUG OF PRECIP MOVING UP THE COAST.
THIS BATCH WILL MOVE INTO THE MYRTLES IN ABOUT AN HOUR. THE HRRR
MODEL INITIALIZED FAIRLY WELL AND SHOWS THE PRECIP WEAKENING LATER
THIS MORNING. SOUTHERLY WINDS WILL INCREASE THIS MORNING...GUSTING
NEAR 20 KTS AT TIMES. ANOTHER BATCH OF PRECIP WILL EMERGE JUST AHEAD
OF THE COLD FRONT THIS AFTERNOON THROUGH THE EARLY EVENING HOURS.
REALLY DIFFICULT TO TIME EVERYTHING...SAFE TO SAY AVIATION
CONDITIONS TODAY WILL BE HIGHLY VARIABLE...WITH IFR CONDITIONS IN
THE HEAVIER PRECIP. COULD NOT RULE OUT THUNDER TODAY...BUT COVERAGE
WILL BE LIMITED AND EMBEDDED IN WIDESPREAD PRECIP. THERE WILL BE
WIND SHIFT LATE TONIGHT AS THE FRONT PUSHES TO THE COAST.
EXTENDED OUTLOOK...PRECIP ENDING NEAR THE COAST LATE TONIGHT WITH
THE COLD FRONT PUSHING TO THE COAST THURSDAY MORNING WITH GUSTY WEST
WINDS. VFR FRIDAY AND SATURDAY. RAIN RETURNING SUNDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM WEDNESDAY...TROPICAL AIRMASS BEHIND A WARM FRONT NOW
SITUATED WELL INLAND IS ADVECTING INTO THE WATERS THIS
MORNING...WITH DEWPOINT TEMPERATURES APPROACHING 70...OR EVEN THE
LOW 70S. THESE DEWPOINT TEMPS ARE 15 DEGREES ABOVE THE COOL SHELF
WATER TEMPS...WHICH IS TYPICALLY A SIGNAL FOR SEA FOG. ATTM
HOWEVER...NO VSBY RESTRICTIONS HAVE BEEN NOTED AND IT MAY BE SIMPLY
DUE TO THE STRENGTH OF THE WIND FIELDS NOT ALLOWING FOR AMPLE PARCEL
RESIDENCE TIME. STILL...THE MARINE DENSE FOG ADVISORY REMAINS AND
WILL CONTINUE AS THERE REDUCED VISIBILITY IN MARINE FOG IS STILL
EXPECTED TO DEVELOP UNTIL THE COLD FRONTAL PASSAGE TONIGHT.
SHOWER ACTIVITY WILL BE SCATTERED THROUGH THE AFTN AND EVE...BEFORE
A MORE STRONGLY FORCED SQUALL LINE WILL CROSS THE WATERS THIS
EVENING AND TONIGHT. WINDS WILL BE GUSTY TODAY EVEN OUTSIDE OF
CONVECTION...AND THE CURRENT SCA REMAINS UNCHANGED FOR BOTH WINDS
AND SEAS...WHICH ARE ALREADY APPROACHING 7 FT AT WILMINGTON HARBOR
BUOY. A WIND SHIFT TO THE WEST WILL OCCUR WITH THE FROPA...WHICH IS
EXPECTED AFTER MIDNIGHT.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 AM WEDNESDAY...COLD FRONT WILL SHIFT FARTHER OFF SHORE ON
THURS AS HIGH PRESSURE BUILDS UP FROM THE GULF COAST. GUSTY W-SW
WINDS EARLY THURS WILL VEER AROUND BECOMING WEST THROUGH THE DAY.
SEAS UP AROUND 5 TO 7 FT SHOULD FALL BELOW SCA THRESHOLDS BY THURS
AFTN WITH HIGHEST SEAS GETTING PUSHED FARTHER OFF SHORE IN STRONGER
W-NW FLOW BEHIND FRONT. WINDS WILL VEER FURTHER TO THE NW AND
LIGHTEN UP LATE THURS INTO FRI AS CENTER OF HIGH SHIFTS CLOSER
OVERHEAD. SEAS WILL BE DOWN TO 2 TO 4 FT BY THURS NIGHT AND DOWN TO
3 FT OR LESS THROUGH FRI AS HIGH PRESSURE MOVES OVERHEAD WITH MORE
VARIABLE WINDS EXPECTED.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 330 AM WEDNESDAY...HIGH PRESSURE WILL SHIFT FARTHER OFF
SHORE ON SATURDAY WITH A RETURN FLOW S-SW 10 KTS OR LESS SETTING
UP. A COLD FRONT WILL DROP SOUTH SUN WITH POSSIBLE WEDGE
DEVELOPING WITH WINDS VEERING AROUND TO THE N-NE AS IT DROPS SOUTH
SUN NIGHT. THIS WILL PUSH SEAS UP A BIT BUT OVERALL BUT EXPECT
SEAS TO GENERALLY 3 FT OR LESS THROUGH THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...DENSE FOG ADVISORY UNTIL 6 PM EST THIS EVENING FOR AMZ250-252-
254-256.
SMALL CRAFT ADVISORY UNTIL NOON EST THURSDAY FOR AMZ250-252-
254-256.
&&
$$
NEAR TERM...17
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...43
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1210 PM CST WED DEC 24 2014
.UPDATE...
ISSUED AT 1206 PM CST WED DEC 24 2014
REGIONAL RADAR MOSAIC CONTINUES TO SHOW LIGHT RETURNS ACROSS PARTS
OF NORTH DAKOTA INTO WESTERN MONTANA. MUCH OF THE PRECIPITATION
HAS NOT BEEN REACHING THE GROUND DUE TO DRY AIR IN THE LOW AND MID
LEVELS. WILL CONTINUE TO CARRY A SMALL CHANCE OF SNOW / RAIN THIS
AFTERNOON...WITH THE RAIN CHANCES MAINLY IN THE SOUTHWEST WHERE
H85 TEMPERATURES HAVE WARMED ABOVE ZERO DEGREES CELSIUS.
LOOKING AT TONIGHT INTO CHRISTMAS DAY...MODELS STILL SUPPORT LIGHT
SNOW ACCUMULATIONS ACROSS THE SOUTHWEST AND FAR SOUTHERN PART OF
THE STATE. THE LATEST WPC GUIDANCE PLACES AN INCH OR TWO IN THE
SOUTHWEST...WHICH IS IN LINE WITH THE GOING FORECAST.
UPDATE ISSUED AT 945 AM CST WED DEC 24 2014
UPDATE HAS BEEN ISSUED. OBSERVATIONS SHOW FOG CONTINUES IN PARTS
OF CENTRAL NORTH DAKOTA...SO EXTENDED PATCHY FOG FOR THE REMAINDER
OF THE MORNING HOURS. EARLY MORNING RADAR MOSAIC SHOWS WEAK ECHOES
MOVING ACROSS PARTS OF WESTERN AND CENTRAL NORTH DAKOTA...BUT
LITTLE TO NO PRECIPITATION HAS BEEN REACHING THE GROUND. A DRY
LAYER IS APPARENT FROM THE 24.12Z BISMARCK SOUNDING WHICH HAS BEEN
INHIBITING THE PRECIPITATION. THINK THE CURRENT SMALL POPS COVER
THIS SCENARIO. DEBATED THE POTENTIAL FOR A BRIEF PERIOD OF VERY
LIGHT FREEZING RAIN / SPRINKLES IN THE SOUTHWEST WHERE WARMER AIR
ALOFT HAS ARRIVED. DECIDED TO ADD IT INTO THE FORECAST FOR JUST A
COUPLE HOURS UNTIL SURFACE TEMPERATURES RISE ABOVE FREEZING.
UPDATE ISSUED AT 637 AM CST WED DEC 24 2014
THE MAIN CHANGE WITH THIS UPDATE WAS TO ADJUST HOURLY FORECAST TEMPS
TO MATCH OBSERVED VALUES IN CENTRAL AND EASTERN LOCATIONS WHERE
TEMPS WERE RUNNING ABOVE FORECAST VALUES DUE TO CLOUD COVER. THE
SAME AREA HAS NUMEROUS REPORTS OF FOG...THOUGH NO SIGNIFICANT
REDUCTIONS IN VISIBILITY AT THIS TIME...GENERALLY 3-5SM VIS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 339 AM CST WED DEC 24 2014
THE MAIN CONCERN IN THE SHORT WILL BE FOG THIS MORNING...THEN
ATTENTION TURNS TO CHANCES OF PRECIPITATION...WITH AND WEATHER TYPE
DURING THE DAY.
CURRENTLY...A WEAK SURFACE RIDGE AXIS EXTENDED ACROSS EASTERN NORTH
DAKOTA - BETWEEN A STRONG LOW PRESSURE SYSTEM OVER THE GREAT LAKES
AREA AND DEVELOPING LOW PRESSURE IN THE LEE OF THE ROCKIES. ALONG
AND EAST OF THIS RIDGE IS A LARGE STRATUS CLOUD FIELD EXTENDING FROM
THE EASTERN DAKOTAS TO THE GREAT LAKES. IN THE WESTERN DAKOTAS
CIRRUS CLOUDS COVERED MOST OF THE AREA...WITH PATCHY/OCCASIONAL FOG
REPORTED...SOMETIMES LIGHT FOG AND SOMETIMES VISIBILITIES DROP DOWN
TO 1/2 MILE OR LESS FOR SHORT PERIODS.
THE VARIOUS RUNS OF THE HRRR MODEL HAVE SUGGESTED THAT THE WESTERN
EDGE OF THE STRATUS DECK SHOULD ERODE WITH TIME...WITH PATCHY AREAS
OF DENSE FOG FORMING IN THE IMMEDIATE CLEARING OF THE STRATUS.
HOWEVER THE MODEL SUGGESTS THE DENSE FOG NOT LASTING/LINGERING IN
ANY ONE AREA. MEANWHILE INCREASING MID LEVEL CLOUDS MOVING IN FROM
EASTERN MONTANA SHOULD EVENTUALLY LIMIT ANY FOG FORMATION. THUS WILL
KEEP A MENTION OF PATCHY FOG OVER THE WESTERN HALF OF THE STATE
THROUGH AROUND 6 AM...THEN CONTINUE THE PATCHY FOG MENTION OVER ALL
OF CENTRAL NORTH DAKOTA UNTIL AROUND 9 AM.
THE NEXT WEATHER SYSTEM TO AFFECT NORTH DAKOTA IS OVER THE WESTERN
COAST OF NORTH AMERICA EARLY THIS MORNING. BROAD ZONAL FLOW WAS OVER
THE NORTHERN PLAINS AHEAD OF THE SYSTEM WITH LOW PRESSURE IN NORTH
CENTRAL CANADA. THE ZONAL FLOW CONTAINS SOME UPPER LEVEL IMPULSE
ENERGY THAT WAS ASSOCIATED WITH A MID-LEVEL DECK OF CLOUDS OVER
SASKATCHEWAN/MONTANA MOVING EASTWARD...WITH SOME LIGHT RADAR RETURNS
SEEN ON THE RADAR MOSAIC. SURFACE LOW PRESSURE IN THE LEE OF THE
ROCKIES THIS MORNING WILL MOVE EAST ACROSS THE DAKOTAS TODAY. WARM
ADVECTION AHEAD/ALONG THE SYSTEM WAS MOVING INTO WESTERN NORTH
DAKOTA THIS MORNING. THERE IS A SLIGHT CHANCE OF LIGHT PRECIPITATION
WITH THIS UPPER LEVEL ENERGY AS IT MOVES EAST ACROSS THE REGION. THE
MAIN QUESTION IS WHETHER FREEZING RAIN WILL BE AN ISSUE THIS
MORNING. THE APPROACH OF THE MID CLOUD DECK WILL MEAN THAT ICE
CRYSTALS WILL BE LIKELY AT MID AND UPPER LEVELS. SHOULD ANY OF THESE
ICE CRYSTALS FALL INTO LOWER LAYERS OF THE ATMOSPHERE...PROGGED
MODEL SOUNDINGS SUGGEST THAT INITIALLY THERE IS A WARM
LAYER/INVERSION - BUT THAT THE FROST POINT WITHIN THIS LAYER IS MUCH
COOLER THAN THE DRY BULB TEMPERATURE. THUS PARTICLES FALLING THROUGH
SHOULD COOL TOWARDS THE FROST POINT AND REMAIN COOL ENOUGH FOR ALL
SNOW. LATER IN THE DAY AS SURFACE TEMPERATURES WARM ABOVE FREEZING -
MAINLY IN THE WEST - PRECIPITATION WOULD CHANGE TO RAIN.
TONIGHT THE COLD FRONT PORTION OF THE WEATHER SYSTEM WILL MOVE
SOUTHEAST ACROSS THE STATE. AS THIS OCCURS...THE UPPER LEVEL FLOW
BECOMES MORE SOUTHWESTERLY ACROSS THE DAKOTAS - AND THE LEADING EDGE
OF A SERIES OF UPPER LEVEL ENERGY IMPULSES AND MID LEVEL MOISTURE
ARRIVES. BY THIS TIME ANY PRECIPITATION THAT FALLS SHOULD BE IN THE
FORM OF SNOW...OR AT LEAST CHANGING OVER FROM RAIN TO SNOW. MOST OF
THE SNOW SHOULD OCCUR OVER MONTANA AND NORTHERN WYOMING...WITH
SOUTHWESTERN NORTH DAKOTA AND NORTHWESTERN SOUTH DAKOTA RECEIVING
SOME LIGHT SNOW BY CHRISTMAS MORNING. ESTIMATES ARE THAT BY
CHRISTMAS MORNING SNOW AMOUNTS OF AROUND 1/2 INCH WOULD BE COMMON IN
THE SOUTHWEST...MAINLY FROM BEACH TO DICKINSON TO HETTINGER AND
POINTS SOUTH AND WEST.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 339 AM CST WED DEC 24 2014
MAIN FORECAST CHALLENGES INVOLVE LIGHT SNOW ACROSS SOUTHERN NORTH
DAKOTA CHRISTMAS DAY AND MUCH COLDER WEATHER BY FRIDAY AND
CONTINUING INTO NEXT WEEK. LATEST 00Z DETERMINISTIC MODELS AS WELL
AS SREF ARE IN GOOD AGREEMENT WITH KEEPING MEASURABLE PRECIP IN THE
FORM OF SNOW ALONG AND SOUTH OF THE ND/SD BORDER ON CHRISTMAS DAY.
THIS INCLUDES THE 00Z NAM WHICH HAS COME BACK IN LINE WITH OTHER
MODEL GUIDANCE WITH A MORE SOUTHWARD LOCATION OF SNOW. MAY SEE
AROUND AN INCH OF SNOW ACCUMULATION CLOSE TO THE STATE BORDER.
WHILE THE SURFACE LOW RESPONSIBLE FOR THIS SNOW MOVES NORTHEAST FROM
THE CENTRAL PLAINS TO THE GREAT LAKES REGION THURSDAY/FRIDAY...
NORTHERLY WINDS WILL ADVECT ARCTIC AIR ACROSS THE NORTHERN PLAINS.
HIGH TEMPS WILL BE IN THE TEENS AND 20S FRIDAY THROUGH THE WEEKEND
BEFORE A STRONGER ARCTIC FRONT PUSHES ACROSS THE REGION EARLY
SUNDAY. SOME DIFFERENCES IN HEIGHT FIELDS DEVELOP BETWEEN
GFS/ECMWF EARLY NEXT WEEK ALTHOUGH BOTH ARE IN AGREEMENT WITH
EXTENSIVE LONG WAVE TROUGH APPROXIMATELY FROM HUDSON BAY TO
INTERMOUNTAIN WEST. GFS HAS -30C CORE AT 850MB OVER NORTHEAST ND
ON TUESDAY WITH THE ECMWF SLIGHTLY WARMER. REGARDLESS...VERY COLD
CONDITIONS EXPECTED WITH WIND CHILLS REACHING DANGEROUS LEVELS
UNDER NORTHWEST FLOW MONDAY NIGHT AND TUESDAY NIGHT WITH 1050MB
SURFACE HIGH SETTING UP OVER WESTERN MONTANA. MAJORITY OF THE CWA
CURRENTLY LOOKS TO REACH WIND CHILL ADVISORY CRITERIA FOR THESE
TIME PERIODS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1206 PM CST WED DEC 24 2014
MANY LOCATIONS ACROSS WESTERN AND CENTRAL NORTH DAKOTA HAVE SEEN
CEILINGS IMPROVE TO VFR...WITH MVFR AND IFR BECOMING LESS
PRONOUNCED. KJMS IS STILL REPORTING IFR CEILINGS...BUT EXPECT
THOSE TO SLOWLY IMPROVE THIS AFTERNOON. A CHANCE OF LIGHT SNOW
WILL INCREASE TONIGHT...MAINLY FOR KDIK AS LOW PRESSURE GATHERS IN
SOUTHWEST SOUTH DAKOTA. COULD ALSO SEE MVFR CEILINGS LATER TONIGHT
AT THE REMAINDER OF THE AERODROMES...KISN..KMOT...KBIS AND KJMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CK
SHORT TERM...JV
LONG TERM...JNS
AVIATION...CK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
946 AM CST WED DEC 24 2014
.UPDATE...
ISSUED AT 945 AM CST WED DEC 24 2014
UPDATE HAS BEEN ISSUED. OBSERVATIONS SHOW FOG CONTINUES IN PARTS
OF CENTRAL NORTH DAKOTA...SO EXTENDED PATCHY FOG FOR THE REMAINDER
OF THE MORNING HOURS. EARLY MORNING RADAR MOSAIC SHOWS WEAK ECHOES
MOVING ACROSS PARTS OF WESTERN AND CENTRAL NORTH DAKOTA...BUT
LITTLE TO NO PRECIPITATION HAS BEEN REACHING THE GROUND. A DRY
LAYER IS APPARENT FROM THE 24.12Z BISMARCK SOUNDING WHICH HAS BEEN
INHIBITING THE PRECIPITATION. THINK THE CURRENT SMALL POPS COVER
THIS SCENARIO. DEBATED THE POTENTIAL FOR A BRIEF PERIOD OF VERY
LIGHT FREEZING RAIN / SPRINKLES IN THE SOUTHWEST WHERE WARMER AIR
ALOFT HAS ARRIVED. DECIDED TO ADD IT INTO THE FORECAST FOR JUST A
COUPLE HOURS UNTIL SURFACE TEMPERATURES RISE ABOVE FREEZING.
UPDATE ISSUED AT 637 AM CST WED DEC 24 2014
THE MAIN CHANGE WITH THIS UPDATE WAS TO ADJUST HOURLY FORECAST TEMPS
TO MATCH OBSERVED VALUES IN CENTRAL AND EASTERN LOCATIONS WHERE
TEMPS WERE RUNNING ABOVE FORECAST VALUES DUE TO CLOUD COVER. THE
SAME AREA HAS NUMEROUS REPORTS OF FOG...THOUGH NO SIGNIFICANT
REDUCTIONS IN VISIBILITY AT THIS TIME...GENERALLY 3-5SM VIS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 339 AM CST WED DEC 24 2014
THE MAIN CONCERN IN THE SHORT WILL BE FOG THIS MORNING...THEN
ATTENTION TURNS TO CHANCES OF PRECIPITATION...WITH AND WEATHER TYPE
DURING THE DAY.
CURRENTLY...A WEAK SURFACE RIDGE AXIS EXTENDED ACROSS EASTERN NORTH
DAKOTA - BETWEEN A STRONG LOW PRESSURE SYSTEM OVER THE GREAT LAKES
AREA AND DEVELOPING LOW PRESSURE IN THE LEE OF THE ROCKIES. ALONG
AND EAST OF THIS RIDGE IS A LARGE STRATUS CLOUD FIELD EXTENDING FROM
THE EASTERN DAKOTAS TO THE GREAT LAKES. IN THE WESTERN DAKOTAS
CIRRUS CLOUDS COVERED MOST OF THE AREA...WITH PATCHY/OCCASIONAL FOG
REPORTED...SOMETIMES LIGHT FOG AND SOMETIMES VISIBILITIES DROP DOWN
TO 1/2 MILE OR LESS FOR SHORT PERIODS.
THE VARIOUS RUNS OF THE HRRR MODEL HAVE SUGGESTED THAT THE WESTERN
EDGE OF THE STRATUS DECK SHOULD ERODE WITH TIME...WITH PATCHY AREAS
OF DENSE FOG FORMING IN THE IMMEDIATE CLEARING OF THE STRATUS.
HOWEVER THE MODEL SUGGESTS THE DENSE FOG NOT LASTING/LINGERING IN
ANY ONE AREA. MEANWHILE INCREASING MID LEVEL CLOUDS MOVING IN FROM
EASTERN MONTANA SHOULD EVENTUALLY LIMIT ANY FOG FORMATION. THUS WILL
KEEP A MENTION OF PATCHY FOG OVER THE WESTERN HALF OF THE STATE
THROUGH AROUND 6 AM...THEN CONTINUE THE PATCHY FOG MENTION OVER ALL
OF CENTRAL NORTH DAKOTA UNTIL AROUND 9 AM.
THE NEXT WEATHER SYSTEM TO AFFECT NORTH DAKOTA IS OVER THE WESTERN
COAST OF NORTH AMERICA EARLY THIS MORNING. BROAD ZONAL FLOW WAS OVER
THE NORTHERN PLAINS AHEAD OF THE SYSTEM WITH LOW PRESSURE IN NORTH
CENTRAL CANADA. THE ZONAL FLOW CONTAINS SOME UPPER LEVEL IMPULSE
ENERGY THAT WAS ASSOCIATED WITH A MID-LEVEL DECK OF CLOUDS OVER
SASKATCHEWAN/MONTANA MOVING EASTWARD...WITH SOME LIGHT RADAR RETURNS
SEEN ON THE RADAR MOSAIC. SURFACE LOW PRESSURE IN THE LEE OF THE
ROCKIES THIS MORNING WILL MOVE EAST ACROSS THE DAKOTAS TODAY. WARM
ADVECTION AHEAD/ALONG THE SYSTEM WAS MOVING INTO WESTERN NORTH
DAKOTA THIS MORNING. THERE IS A SLIGHT CHANCE OF LIGHT PRECIPITATION
WITH THIS UPPER LEVEL ENERGY AS IT MOVES EAST ACROSS THE REGION. THE
MAIN QUESTION IS WHETHER FREEZING RAIN WILL BE AN ISSUE THIS
MORNING. THE APPROACH OF THE MID CLOUD DECK WILL MEAN THAT ICE
CRYSTALS WILL BE LIKELY AT MID AND UPPER LEVELS. SHOULD ANY OF THESE
ICE CRYSTALS FALL INTO LOWER LAYERS OF THE ATMOSPHERE...PROGGED
MODEL SOUNDINGS SUGGEST THAT INITIALLY THERE IS A WARM
LAYER/INVERSION - BUT THAT THE FROST POINT WITHIN THIS LAYER IS MUCH
COOLER THAN THE DRY BULB TEMPERATURE. THUS PARTICLES FALLING THROUGH
SHOULD COOL TOWARDS THE FROST POINT AND REMAIN COOL ENOUGH FOR ALL
SNOW. LATER IN THE DAY AS SURFACE TEMPERATURES WARM ABOVE FREEZING -
MAINLY IN THE WEST - PRECIPITATION WOULD CHANGE TO RAIN.
TONIGHT THE COLD FRONT PORTION OF THE WEATHER SYSTEM WILL MOVE
SOUTHEAST ACROSS THE STATE. AS THIS OCCURS...THE UPPER LEVEL FLOW
BECOMES MORE SOUTHWESTERLY ACROSS THE DAKOTAS - AND THE LEADING EDGE
OF A SERIES OF UPPER LEVEL ENERGY IMPULSES AND MID LEVEL MOISTURE
ARRIVES. BY THIS TIME ANY PRECIPITATION THAT FALLS SHOULD BE IN THE
FORM OF SNOW...OR AT LEAST CHANGING OVER FROM RAIN TO SNOW. MOST OF
THE SNOW SHOULD OCCUR OVER MONTANA AND NORTHERN WYOMING...WITH
SOUTHWESTERN NORTH DAKOTA AND NORTHWESTERN SOUTH DAKOTA RECEIVING
SOME LIGHT SNOW BY CHRISTMAS MORNING. ESTIMATES ARE THAT BY
CHRISTMAS MORNING SNOW AMOUNTS OF AROUND 1/2 INCH WOULD BE COMMON IN
THE SOUTHWEST...MAINLY FROM BEACH TO DICKINSON TO HETTINGER AND
POINTS SOUTH AND WEST.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 339 AM CST WED DEC 24 2014
MAIN FORECAST CHALLENGES INVOLVE LIGHT SNOW ACROSS SOUTHERN NORTH
DAKOTA CHRISTMAS DAY AND MUCH COLDER WEATHER BY FRIDAY AND
CONTINUING INTO NEXT WEEK. LATEST 00Z DETERMINISTIC MODELS AS WELL
AS SREF ARE IN GOOD AGREEMENT WITH KEEPING MEASURABLE PRECIP IN THE
FORM OF SNOW ALONG AND SOUTH OF THE ND/SD BORDER ON CHRISTMAS DAY.
THIS INCLUDES THE 00Z NAM WHICH HAS COME BACK IN LINE WITH OTHER
MODEL GUIDANCE WITH A MORE SOUTHWARD LOCATION OF SNOW. MAY SEE
AROUND AN INCH OF SNOW ACCUMULATION CLOSE TO THE STATE BORDER.
WHILE THE SURFACE LOW RESPONSIBLE FOR THIS SNOW MOVES NORTHEAST FROM
THE CENTRAL PLAINS TO THE GREAT LAKES REGION THURSDAY/FRIDAY...
NORTHERLY WINDS WILL ADVECT ARCTIC AIR ACROSS THE NORTHERN PLAINS.
HIGH TEMPS WILL BE IN THE TEENS AND 20S FRIDAY THROUGH THE WEEKEND
BEFORE A STRONGER ARCTIC FRONT PUSHES ACROSS THE REGION EARLY
SUNDAY. SOME DIFFERENCES IN HEIGHT FIELDS DEVELOP BETWEEN
GFS/ECMWF EARLY NEXT WEEK ALTHOUGH BOTH ARE IN AGREEMENT WITH
EXTENSIVE LONG WAVE TROUGH APPROXIMATELY FROM HUDSON BAY TO
INTERMOUNTAIN WEST. GFS HAS -30C CORE AT 850MB OVER NORTHEAST ND
ON TUESDAY WITH THE ECMWF SLIGHTLY WARMER. REGARDLESS...VERY COLD
CONDITIONS EXPECTED WITH WIND CHILLS REACHING DANGEROUS LEVELS
UNDER NORTHWEST FLOW MONDAY NIGHT AND TUESDAY NIGHT WITH 1050MB
SURFACE HIGH SETTING UP OVER WESTERN MONTANA. MAJORITY OF THE CWA
CURRENTLY LOOKS TO REACH WIND CHILL ADVISORY CRITERIA FOR THESE
TIME PERIODS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 637 AM CST WED DEC 24 2014
WIDESPREAD MVFR/IFR WILL CONTINUE FROM KBIS-KMOT-KJMS THIS MORNING
IN CIGS WITH OCNL FOG. GRADUAL CLEARING FROM WEST TO EAST WILL REACH
KBIS-KMOT LINE AFTER 13Z-14Z...AND KJMS AROUND 18Z. INITIAL LOWERING
OF VSBY AND CIG AT THE WESTERN EDGE OF THE LOW STRATUS DECK.
KISN-KDIK EXPECTED TO BE VFR AT FIRST WITH MID CLOUDS MOVING IN FROM
THE WEST. NEXT SYSTEM MOVING IN FROM THE WEST EXPECTED TO BRING
LOWER CIGS AT KISN/KDIK AFT 00Z AND MAY BRING LIGHT SNOW TO KDIK.
DID NOT MENTION YET IN TAFS AS CONFIDENCE THAT EXTENT OF LIGHT SNOW
IN MONTANA/WYOMING WILL REACH KDIK. COLD FRONT ENTERS NORTHWESTERN
NORTH DAKOTA AROUND 00Z IN THE NORTHWEST...MOVES SOUTHEAST REACHING
KJMS AROUND 08Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CK
SHORT TERM...JV
LONG TERM...JNS
AVIATION...JV
AREA FORECAST DISCUSSION
NWS BISMARCK ND
637 AM CST WED DEC 24 2014
.UPDATE...
ISSUED AT 637 AM CST WED DEC 24 2014
THE MAIN CHANGE WITH THIS UPDATE WAS TO ADJUST HOURLY FORECAST TEMPS
TO MATCH OBSERVED VALUES IN CENTRAL AND EASTERN LOCATIONS WHERE
TEMPS WERE RUNNING ABOVE FORECAST VALUES DUE TO CLOUD COVER. THE
SAME AREA HAS NUMEROUS REPORTS OF FOG...THOUGH NO SIGNIFICANT
REDUCTIONS IN VISIBILITY AT THIS TIME...GENERALLY 3-5SM VIS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 339 AM CST WED DEC 24 2014
THE MAIN CONCERN IN THE SHORT WILL BE FOG THIS MORNING...THEN
ATTENTION TURNS TO CHANCES OF PRECIPITATION...WITH AND WEATHER TYPE
DURING THE DAY.
CURRENTLY...A WEAK SURFACE RIDGE AXIS EXTENDED ACROSS EASTERN NORTH
DAKOTA - BETWEEN A STRONG LOW PRESSURE SYSTEM OVER THE GREAT LAKES
AREA AND DEVELOPING LOW PRESSURE IN THE LEE OF THE ROCKIES. ALONG
AND EAST OF THIS RIDGE IS A LARGE STRATUS CLOUD FIELD EXTENDING FROM
THE EASTERN DAKOTAS TO THE GREAT LAKES. IN THE WESTERN DAKOTAS
CIRRUS CLOUDS COVERED MOST OF THE AREA...WITH PATCHY/OCCASIONAL FOG
REPORTED...SOMETIMES LIGHT FOG AND SOMETIMES VISIBILITIES DROP DOWN
TO 1/2 MILE OR LESS FOR SHORT PERIODS.
THE VARIOUS RUNS OF THE HRRR MODEL HAVE SUGGESTED THAT THE WESTERN
EDGE OF THE STRATUS DECK SHOULD ERODE WITH TIME...WITH PATCHY AREAS
OF DENSE FOG FORMING IN THE IMMEDIATE CLEARING OF THE STRATUS.
HOWEVER THE MODEL SUGGESTS THE DENSE FOG NOT LASTING/LINGERING IN
ANY ONE AREA. MEANWHILE INCREASING MID LEVEL CLOUDS MOVING IN FROM
EASTERN MONTANA SHOULD EVENTUALLY LIMIT ANY FOG FORMATION. THUS WILL
KEEP A MENTION OF PATCHY FOG OVER THE WESTERN HALF OF THE STATE
THROUGH AROUND 6 AM...THEN CONTINUE THE PATCHY FOG MENTION OVER ALL
OF CENTRAL NORTH DAKOTA UNTIL AROUND 9 AM.
THE NEXT WEATHER SYSTEM TO AFFECT NORTH DAKOTA IS OVER THE WESTERN
COAST OF NORTH AMERICA EARLY THIS MORNING. BROAD ZONAL FLOW WAS OVER
THE NORTHERN PLAINS AHEAD OF THE SYSTEM WITH LOW PRESSURE IN NORTH
CENTRAL CANADA. THE ZONAL FLOW CONTAINS SOME UPPER LEVEL IMPULSE
ENERGY THAT WAS ASSOCIATED WITH A MID-LEVEL DECK OF CLOUDS OVER
SASKATCHEWAN/MONTANA MOVING EASTWARD...WITH SOME LIGHT RADAR RETURNS
SEEN ON THE RADAR MOSAIC. SURFACE LOW PRESSURE IN THE LEE OF THE
ROCKIES THIS MORNING WILL MOVE EAST ACROSS THE DAKOTAS TODAY. WARM
ADVECTION AHEAD/ALONG THE SYSTEM WAS MOVING INTO WESTERN NORTH
DAKOTA THIS MORNING. THERE IS A SLIGHT CHANCE OF LIGHT PRECIPITATION
WITH THIS UPPER LEVEL ENERGY AS IT MOVES EAST ACROSS THE REGION. THE
MAIN QUESTION IS WHETHER FREEZING RAIN WILL BE AN ISSUE THIS
MORNING. THE APPROACH OF THE MID CLOUD DECK WILL MEAN THAT ICE
CRYSTALS WILL BE LIKELY AT MID AND UPPER LEVELS. SHOULD ANY OF THESE
ICE CRYSTALS FALL INTO LOWER LAYERS OF THE ATMOSPHERE...PROGGED
MODEL SOUNDINGS SUGGEST THAT INITIALLY THERE IS A WARM
LAYER/INVERSION - BUT THAT THE FROST POINT WITHIN THIS LAYER IS MUCH
COOLER THAN THE DRY BULB TEMPERATURE. THUS PARTICLES FALLING THROUGH
SHOULD COOL TOWARDS THE FROST POINT AND REMAIN COOL ENOUGH FOR ALL
SNOW. LATER IN THE DAY AS SURFACE TEMPERATURES WARM ABOVE FREEZING -
MAINLY IN THE WEST - PRECIPITATION WOULD CHANGE TO RAIN.
TONIGHT THE COLD FRONT PORTION OF THE WEATHER SYSTEM WILL MOVE
SOUTHEAST ACROSS THE STATE. AS THIS OCCURS...THE UPPER LEVEL FLOW
BECOMES MORE SOUTHWESTERLY ACROSS THE DAKOTAS - AND THE LEADING EDGE
OF A SERIES OF UPPER LEVEL ENERGY IMPULSES AND MID LEVEL MOISTURE
ARRIVES. BY THIS TIME ANY PRECIPITATION THAT FALLS SHOULD BE IN THE
FORM OF SNOW...OR AT LEAST CHANGING OVER FROM RAIN TO SNOW. MOST OF
THE SNOW SHOULD OCCUR OVER MONTANA AND NORTHERN WYOMING...WITH
SOUTHWESTERN NORTH DAKOTA AND NORTHWESTERN SOUTH DAKOTA RECEIVING
SOME LIGHT SNOW BY CHRISTMAS MORNING. ESTIMATES ARE THAT BY
CHRISTMAS MORNING SNOW AMOUNTS OF AROUND 1/2 INCH WOULD BE COMMON IN
THE SOUTHWEST...MAINLY FROM BEACH TO DICKINSON TO HETTINGER AND
POINTS SOUTH AND WEST.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 339 AM CST WED DEC 24 2014
MAIN FORECAST CHALLENGES INVOLVE LIGHT SNOW ACROSS SOUTHERN NORTH
DAKOTA CHRISTMAS DAY AND MUCH COLDER WEATHER BY FRIDAY AND
CONTINUING INTO NEXT WEEK. LATEST 00Z DETERMINISTIC MODELS AS WELL
AS SREF ARE IN GOOD AGREEMENT WITH KEEPING MEASURABLE PRECIP IN THE
FORM OF SNOW ALONG AND SOUTH OF THE ND/SD BORDER ON CHRISTMAS DAY.
THIS INCLUDES THE 00Z NAM WHICH HAS COME BACK IN LINE WITH OTHER
MODEL GUIDANCE WITH A MORE SOUTHWARD LOCATION OF SNOW. MAY SEE
AROUND AN INCH OF SNOW ACCUMULATION CLOSE TO THE STATE BORDER.
WHILE THE SURFACE LOW RESPONSIBLE FOR THIS SNOW MOVES NORTHEAST FROM
THE CENTRAL PLAINS TO THE GREAT LAKES REGION THURSDAY/FRIDAY...
NORTHERLY WINDS WILL ADVECT ARCTIC AIR ACROSS THE NORTHERN PLAINS.
HIGH TEMPS WILL BE IN THE TEENS AND 20S FRIDAY THROUGH THE WEEKEND
BEFORE A STRONGER ARCTIC FRONT PUSHES ACROSS THE REGION EARLY
SUNDAY. SOME DIFFERENCES IN HEIGHT FIELDS DEVELOP BETWEEN
GFS/ECMWF EARLY NEXT WEEK ALTHOUGH BOTH ARE IN AGREEMENT WITH
EXTENSIVE LONG WAVE TROUGH APPROXIMATELY FROM HUDSON BAY TO
INTERMOUNTAIN WEST. GFS HAS -30C CORE AT 850MB OVER NORTHEAST ND
ON TUESDAY WITH THE ECMWF SLIGHTLY WARMER. REGARDLESS...VERY COLD
CONDITIONS EXPECTED WITH WIND CHILLS REACHING DANGEROUS LEVELS
UNDER NORTHWEST FLOW MONDAY NIGHT AND TUESDAY NIGHT WITH 1050MB
SURFACE HIGH SETTING UP OVER WESTERN MONTANA. MAJORITY OF THE CWA
CURRENTLY LOOKS TO REACH WIND CHILL ADVISORY CRITERIA FOR THESE
TIME PERIODS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 637 AM CST WED DEC 24 2014
WIDESPREAD MVFR/IFR WILL CONTINUE FROM KBIS-KMOT-KJMS THIS MORNING
IN CIGS WITH OCNL FOG. GRADUAL CLEARING FROM WEST TO EAST WILL REACH
KBIS-KMOT LINE AFTER 13Z-14Z...AND KJMS AROUND 18Z. INITIAL LOWERING
OF VSBY AND CIG AT THE WESTERN EDGE OF THE LOW STRATUS DECK.
KISN-KDIK EXPECTED TO BE VFR AT FIRST WITH MID CLOUDS MOVING IN FROM
THE WEST. NEXT SYSTEM MOVING IN FROM THE WEST EXPECTED TO BRING
LOWER CIGS AT KISN/KDIK AFT 00Z AND MAY BRING LIGHT SNOW TO KDIK.
DID NOT MENTION YET IN TAFS AS CONFIDENCE THAT EXTENT OF LIGHT SNOW
IN MONTANA/WYOMING WILL REACH KDIK. COLD FRONT ENTERS NORTHWESTERN
NORTH DAKOTA AROUND 00Z IN THE NORTHWEST...MOVES SOUTHEAST REACHING
KJMS AROUND 08Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JNS
SHORT TERM...JV
LONG TERM...JNS
AVIATION...JV
AREA FORECAST DISCUSSION
NWS BISMARCK ND
339 AM CST WED DEC 24 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 339 AM CST WED DEC 24 2014
THE MAIN CONCERN IN THE SHORT WILL BE FOG THIS MORNING...THEN
ATTENTION TURNS TO CHANCES OF PRECIPITATION...WITH AND WEATHER TYPE
DURING THE DAY.
CURRENTLY...A WEAK SURFACE RIDGE AXIS EXTENDED ACROSS EASTERN NORTH
DAKOTA - BETWEEN A STRONG LOW PRESSURE SYSTEM OVER THE GREAT LAKES
AREA AND DEVELOPING LOW PRESSURE IN THE LEE OF THE ROCKIES. ALONG
AND EAST OF THIS RIDGE IS A LARGE STRATUS CLOUD FIELD EXTENDING FROM
THE EASTERN DAKOTAS TO THE GREAT LAKES. IN THE WESTERN DAKOTAS
CIRRUS CLOUDS COVERED MOST OF THE AREA...WITH PATCHY/OCCASIONAL FOG
REPORTED...SOMETIMES LIGHT FOG AND SOMETIMES VISIBILITIES DROP DOWN
TO 1/2 MILE OR LESS FOR SHORT PERIODS.
THE VARIOUS RUNS OF THE HRRR MODEL HAVE SUGGESTED THAT THE WESTERN
EDGE OF THE STRATUS DECK SHOULD ERODE WITH TIME...WITH PATCHY AREAS
OF DENSE FOG FORMING IN THE IMMEDIATE CLEARING OF THE STRATUS.
HOWEVER THE MODEL SUGGESTS THE DENSE FOG NOT LASTING/LINGERING IN
ANY ONE AREA. MEANWHILE INCREASING MID LEVEL CLOUDS MOVING IN FROM
EASTERN MONTANA SHOULD EVENTUALLY LIMIT ANY FOG FORMATION. THUS WILL
KEEP A MENTION OF PATCHY FOG OVER THE WESTERN HALF OF THE STATE
THROUGH AROUND 6 AM...THEN CONTINUE THE PATCHY FOG MENTION OVER ALL
OF CENTRAL NORTH DAKOTA UNTIL AROUND 9 AM.
THE NEXT WEATHER SYSTEM TO AFFECT NORTH DAKOTA IS OVER THE WESTERN
COAST OF NORTH AMERICA EARLY THIS MORNING. BROAD ZONAL FLOW WAS OVER
THE NORTHERN PLAINS AHEAD OF THE SYSTEM WITH LOW PRESSURE IN NORTH
CENTRAL CANADA. THE ZONAL FLOW CONTAINS SOME UPPER LEVEL IMPULSE
ENERGY THAT WAS ASSOCIATED WITH A MID-LEVEL DECK OF CLOUDS OVER
SASKATCHEWAN/MONTANA MOVING EASTWARD...WITH SOME LIGHT RADAR RETURNS
SEEN ON THE RADAR MOSAIC. SURFACE LOW PRESSURE IN THE LEE OF THE
ROCKIES THIS MORNING WILL MOVE EAST ACROSS THE DAKOTAS TODAY. WARM
ADVECTION AHEAD/ALONG THE SYSTEM WAS MOVING INTO WESTERN NORTH
DAKOTA THIS MORNING. THERE IS A SLIGHT CHANCE OF LIGHT PRECIPITATION
WITH THIS UPPER LEVEL ENERGY AS IT MOVES EAST ACROSS THE REGION. THE
MAIN QUESTION IS WHETHER FREEZING RAIN WILL BE AN ISSUE THIS
MORNING. THE APPROACH OF THE MID CLOUD DECK WILL MEAN THAT ICE
CRYSTALS WILL BE LIKELY AT MID AND UPPER LEVELS. SHOULD ANY OF THESE
ICE CRYSTALS FALL INTO LOWER LAYERS OF THE ATMOSPHERE...PROGGED
MODEL SOUNDINGS SUGGEST THAT INITIALLY THERE IS A WARM
LAYER/INVERSION - BUT THAT THE FROST POINT WITHIN THIS LAYER IS MUCH
COOLER THAN THE DRY BULB TEMPERATURE. THUS PARTICLES FALLING THROUGH
SHOULD COOL TOWARDS THE FROST POINT AND REMAIN COOL ENOUGH FOR ALL
SNOW. LATER IN THE DAY AS SURFACE TEMPERATURES WARM ABOVE FREEZING -
MAINLY IN THE WEST - PRECIPITATION WOULD CHANGE TO RAIN.
TONIGHT THE COLD FRONT PORTION OF THE WEATHER SYSTEM WILL MOVE
SOUTHEAST ACROSS THE STATE. AS THIS OCCURS...THE UPPER LEVEL FLOW
BECOMES MORE SOUTHWESTERLY ACROSS THE DAKOTAS - AND THE LEADING EDGE
OF A SERIES OF UPPER LEVEL ENERGY IMPULSES AND MID LEVEL MOISTURE
ARRIVES. BY THIS TIME ANY PRECIPITATION THAT FALLS SHOULD BE IN THE
FORM OF SNOW...OR AT LEAST CHANGING OVER FROM RAIN TO SNOW. MOST OF
THE SNOW SHOULD OCCUR OVER MONTANA AND NORTHERN WYOMING...WITH
SOUTHWESTERN NORTH DAKOTA AND NORTHWESTERN SOUTH DAKOTA RECEIVING
SOME LIGHT SNOW BY CHRISTMAS MORNING. ESTIMATES ARE THAT BY
CHRISTMAS MORNING SNOW AMOUNTS OF AROUND 1/2 INCH WOULD BE COMMON IN
THE SOUTHWEST...MAINLY FROM BEACH TO DICKINSON TO HETTINGER AND
POINTS SOUTH AND WEST.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 339 AM CST WED DEC 24 2014
MAIN FORECAST CHALLENGES INVOLVE LIGHT SNOW ACROSS SOUTHERN NORTH
DAKOTA CHRISTMAS DAY AND MUCH COLDER WEATHER BY FRIDAY AND
CONTINUING INTO NEXT WEEK. LATEST 00Z DETERMINISTIC MODELS AS WELL
AS SREF ARE IN GOOD AGREEMENT WITH KEEPING MEASURABLE PRECIP IN THE
FORM OF SNOW ALONG AND SOUTH OF THE ND/SD BORDER ON CHRISTMAS DAY.
THIS INCLUDES THE 00Z NAM WHICH HAS COME BACK IN LINE WITH OTHER
MODEL GUIDANCE WITH A MORE SOUTHWARD LOCATION OF SNOW. MAY SEE
AROUND AN INCH OF SNOW ACCUMULATION CLOSE TO THE STATE BORDER.
WHILE THE SURFACE LOW RESPONSIBLE FOR THIS SNOW MOVES NORTHEAST FROM
THE CENTRAL PLAINS TO THE GREAT LAKES REGION THURSDAY/FRIDAY...
NORTHERLY WINDS WILL ADVECT ARCTIC AIR ACROSS THE NORTHERN PLAINS.
HIGH TEMPS WILL BE IN THE TEENS AND 20S FRIDAY THROUGH THE WEEKEND
BEFORE A STRONGER ARCTIC FRONT PUSHES ACROSS THE REGION EARLY
SUNDAY. SOME DIFFERENCES IN HEIGHT FIELDS DEVELOP BETWEEN
GFS/ECMWF EARLY NEXT WEEK ALTHOUGH BOTH ARE IN AGREEMENT WITH
EXTENSIVE LONG WAVE TROUGH APPROXIMATELY FROM HUDSON BAY TO
INTERMOUNTAIN WEST. GFS HAS -30C CORE AT 850MB OVER NORTHEAST ND
ON TUESDAY WITH THE ECMWF SLIGHTLY WARMER. REGARDLESS...VERY COLD
CONDITIONS EXPECTED WITH WIND CHILLS REACHING DANGEROUS LEVELS
UNDER NORTHWEST FLOW MONDAY NIGHT AND TUESDAY NIGHT WITH 1050MB
SURFACE HIGH SETTING UP OVER WESTERN MONTANA. MAJORITY OF THE CWA
CURRENTLY LOOKS TO REACH WIND CHILL ADVISORY CRITERIA FOR THESE
TIME PERIODS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1236 AM CST WED DEC 24 2014
WIDESPREAD MVFR/IFR WILL CONTINUE FROM KBIS-KMOT-KJMS THIS MORNING
IN CIGS WITH OCNL FOG. GRADUAL CLEARING FROM WEST TO EAST WILL REACH
KBIS-KMOT LINE AFTER 10Z/4 AM CST. KISN-KDIK EXPECTED TO BE VFR WITH
OCNL MVFR IN FOG UNTIL AROUND 10Z-12Z WHEN MID CLOUDS SHOULD MOVE IN
FROM THE WEST AND BREAK UP PATCHY FOG. NEXT SYSTEM MOVING IN FROM
THE WEST EXPECTED TO BRING LOWER CIGS AT KISN/KDIK AFT 00Z AND MAY
BRING LIGHT SNOW TO KDIK. DID NOT MENTION YET IN TAFS AS CONFIDENCE
THAT EXTENT OF LIGHT SNOW IN MONTANA/WYOMING WILL REACH KDIK.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JV
LONG TERM...JNS
AVIATION...JV
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1236 AM CST WED DEC 24 2014
.UPDATE...
ISSUED AT 1236 AM CST WED DEC 24 2014
MAIN CONCERN THIS UPDATE IS HOW PATCHY/WIDESPREAD FOG WILL
MATERIALIZE. WESTERN NORTH DAKOTA IS MAINLY CLEAR EXCEPT WITH SOME
HIGH CIRRUS CLOUDS. THERE HAVE BEEN SOME REPORTS OF PATCHY FOG. A
MID CLOUD DECK IS FORECAST TO ENTER THE WEST LATER THIS MORNING
WHICH SHOULD LIMIT THE EXTENT/DENSENESS OF ANY FOG. HOWEVER CENTRAL
NORTH DAKOTA MAY SEE FOG AS THE WESTERN EDGE OF A LARGE LOW CLOUD
DECK CURRENTLY OVER THE EASTERN DAKOTAS/MINNESOTA ERODES/MOVES EAST.
WILL ADD MENTION OF PATCHY FOG OVER CENTRAL NORTH DAKOTA THIS
MORNING.
THE OTHER CONCERN IS TEMPERATURES. IN CLEARING AREAS TEMPERATURES
HAD DROPPED TO AROUND 10 TO 15 DEGREES...THE RISE BACK INTO THE 20S
AS CLOUDS MOVE OVER THE LOCALE. GOING FOR LOWS OF 10 TO 20 BUT
CONFIDENCE IS LOW DUE TO RANDOM CLEARING/FOG EXPECTED DURING THE
EARLY MORNING HOURS.
UPDATE ISSUED AT 932 PM CST TUE DEC 23 2014
CLEARING SKIES WEST RESULTING SOME PATCHY FOG. ADDED THIS TO THE
FORECAST. INCREASING HIGH CLOUDS LATER TONIGHT SHOULD LIMIT THE
EXTENT OF THE FOG HOWEVER. ALSO LOWERED MIN TEMPS ABOUT 5 - 7 DEGREES
SOUTHWEST.
UPDATE ISSUED AT 634 PM CST TUE DEC 23 2014
ADDED A SLIGHT CHANCE FOR SNOW AND FREEZING DRIZZLE ACROSS
NORTHWEST AND CENTRAL NORTH DAKOTA FOR THE EARLY EVENING HOURS.
RADAR RETURNS SUGGEST LIGHT PRECIP SHOWING UP BETWEEN BISMARCK AND
MINOT AS OF 630 PM CST. BUFKIT SOUNDINGS SHOW A LACK OF ICE
CRYSTALS TO ALLOWING SUPER COOLER WATER TO EXIST. THIS THROUGH 9
PM CST. REMAINDER OF THE FORECAST LOOKS GOOD.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 245 PM CST TUE DEC 23 2014
THE MAIN CONCERN IN THE SHORT WILL BE LINGERING LIGHT SNOW
CHANCES THIS AFTERNOON/EVENING...WITH CHANCES FOR RAIN OR SNOW ON
WEDNESDAY.
AFTERNOON REGIONAL RADAR MOSAIC SHOWS LIGHT SNOW ACROSS PARTS OF
WESTERN AND CENTRAL NORTH DAKOTA. THE SNOW HAS DIMINISHED IN
COVERAGE OVER THE PAST COUPLE HOURS...AND SHORT TERM MODELS
SUPPORT THAT TREND. WILL CARRY ONLY SMALL POPS WITH LITTLE TO NO
ADDITIONAL SNOW ACCUMULATION EXPECTED.
CONSIDERED ADDING PATCHY FOG IN THE WEST IN PROXIMITY TO A SURFACE
RIDGE AXIS. THE LATEST HRRR INDICATES THERE IS A CHANCE OF REDUCED
VISIBILITIES LATE TONIGHT INTO EARLY WEDNESDAY...BUT WAS NOT QUITE
CONFIDENT ENOUGH TO PUT IT IN YET. WILL LET LATER SHIFTS MONITOR
AND ADD IF NECESSARY.
H85 WARM AIR ADVECTION INCREASES WEDNESDAY WITH MODELS DIFFERING
IN REGARDS TO THE AREAL COVERAGE OF PRECIPITATION ASSOCIATED WITH
IT. THE SREF GENERALLY SUPPORTS KEEPING THE PRIMARY PRECIPITATION
CHANCES CONFINED TO NORTHERN PARTS OF THE STATE THROUGH WEDNESDAY
AFTERNOON...WHILE THE DETERMINISTIC NAM/GFS/ECMWF BRING CHANCES
FARTHER SOUTH. HAVE EXPANDED SLIGHT CHANCE POPS SOUTHWARD TO
ACKNOWLEDGE THE DETERMINISTIC SOLUTIONS...WHICH ALSO LINES UP WITH
THE H85 WARM AIR ADVECTION. PRECIPITATION TYPE WILL ALSO BE A
CONCERN WITH H85 TEMPERATURES RISING ABOVE ZERO DEGREES CELSIUS IN
THE SOUTHWEST. THE GOOD NEWS IS SURFACE TEMPERATURES ALSO WARM
ABOVE FREEZING IN THAT AREA...BUT IT WILL BE SOMETHING TO WATCH IN
REGARDS TO PRECIPITATION TYPE.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 245 PM CST TUE DEC 23 2014
FOCUS IN THE LONG TERM IS ON THE LARGE SCALE UPPER LEVEL TROUGH
MOVING ACROSS THE CENTRAL CONUS THURSDAY INTO THE WEEKEND AND THE
COOLING TREND COMING THIS WEEKEND.
THE 12 UTC MODEL GUIDANCE IS IN GOOD AGREEMENT ON THE LARGE SCALE
PATTERN...PROGRESSING A DEEP UPPER LEVEL TROUGH FROM THE ROCKIES
EARLY THURSDAY TO THE GREAT LAKES REGION SATURDAY. FOR THE NORTHERN
PLAINS THE 12 UTC MODEL GUIDANCE SHOWS THE MAJORITY OF PRECIPITATION
FALLING ACROSS SOUTHEASTERN MONTANA AS WELL AS NORTHERN AND WESTERN
SOUTH DAKOTA WEDNESDAY NIGHT THROUGH FRIDAY...WITH ONLY MINOR
ACCUMULATIONS ACROSS SOUTHERN NORTH DAKOTA. HOWEVER THE 12 UTC RUNS
OF THE NAM AND GEM-NHEM SHOW PRECIPITATION FALLING FURTHER NORTH
ALONG AND SOUTH OF THE I-94 CORRIDOR IN WESTERN AND CENTRAL NORTH
DAKOTA WEDNESDAY NIGHT THROUGH THURSDAY MORNING. WITH THAT SAID
THESE LATEST 12 UTC RUNS ARE OUTLIERS WITH PREVIOUS MODEL RUNS AND
THE CURRENT 12 UTC RUNS OF THE GFS AND ECMWF. WILL HAVE TO WATCH TO
SEE IF THE HEAVIER PRECIPITATION SOLUTIONS OF THE NAM AND GEM-NHEM
CONTINUE OVER THE NEXT FEW MODELS RUNS...AS THEY SUGGEST BETWEEN 2
AND 4 INCHES COULD FALL OVER THE PERIOD WHICH MAY PROMPT HEADLINES.
HOWEVER...AT THIS TIME WENT WITH A MODEL BLEND FOR THE FORECAST AND
THINKING ONLY AROUND AN INCH TO TWO OF SNOW IN THE SOUTHWEST WITH
GENERALLY LESS THAN AN INCH ELSEWHERE...WHICH DOES NOT REQUIRE ANY
HEADLINES.
PRECIPITATION TYPE WEDNESDAY NIGHT THROUGH FRIDAY APPEARS TO BE ALL
SNOW. MID LEVELS SHOULD BE MOIST ENOUGH FOR ICE CRYSTALS AND
TEMPERATURE PROFILES WILL BE BELOW FREEZING SO THAT NO MELTING
OCCURS. SOME FREEZING DRIZZLE IS POSSIBLE AT TIMES THURSDAY NIGHT AS
THE SYSTEM MOVES SOUTHEAST AND MID LEVELS DRY OUT...HOWEVER
ACCUMULATION WOULD BE MINOR AND ANY PERIOD OF FREEZING DRIZZLE WOULD
BE BRIEF. THUS ONLY MENTION OF SNOW IN THE GRIDS FOR NOW.
ARCTIC AIR WILL FILTER IN BEHIND THIS SYSTEM WITH HIGHS DROPPING
FROM THE 20S CHRISTMAS DAY TO THE SINGLE DIGITS NORTH ON FRIDAY AND
TEENS ELSEWHERE. WIND CHILLS SUNDAY NIGHT AND MONDAY NIGHT WILL BE
VERY COLD. CURRENT FORECAST HAS WIND CHILLS APPROACHING 25 BELOW
ZERO ACROSS THE NORTHERN HALF OF THE STATE EARLY MONDAY MORNING AND
DROPPING TO 25 BELOW ZERO TO 35 BELOW ZERO ACROSS MUCH OF THE STATE
MONDAY NIGHT INTO TUESDAY MORNING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1236 AM CST WED DEC 24 2014
WIDESPREAD MVFR/IFR WILL CONTINUE FROM KBIS-KMOT-KJMS THIS MORNING
IN CIGS WITH OCNL FOG. GRADUAL CLEARING FROM WEST TO EAST WILL REACH
KBIS-KMOT LINE AFTER 10Z/4 AM CST. KISN-KDIK EXPECTED TO BE VFR WITH
OCNL MVFR IN FOG UNTIL AROUND 10Z-12Z WHEN MID CLOUDS SHOULD MOVE IN
FROM THE WEST AND BREAK UP PATCHY FOG. NEXT SYSTEM MOVING IN FROM
THE WEST EXPECTED TO BRING LOWER CIGS AT KISN/KDIK AFT 00Z AND MAY
BRING LIGHT SNOW TO KDIK. DID NOT MENTION YET IN TAFS AS CONFIDENCE
THAT EXTENT OF LIGHT SNOW IN MONTANA/WYOMING WILL REACH KDIK.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JV
SHORT TERM...CK
LONG TERM...MM
AVIATION...JV
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1225 PM EST WED DEC 24 2014
.SYNOPSIS...
LOW PRESSURE WILL MOVE NORTH OUT OF THE TENNESSEE VALLEY TODAY TO
OHIO AND LAKE ERIE BY THIS EVENING. A TRAILING COLD FRONT WILL SWEEP
EAST ACROSS THE REGION THIS EVENING. STRONG GUSTY WINDS ARE EXPECTED
WITH THIS STORM SYSTEM ACROSS THE AREA. A RIDGE OF HIGH PRESSURE
WILL BUILD NORTH INTO THE REGION BY THURSDAY EVENING. LOW PRESSURE
WILL BUILD NORTHEAST INTO THE NORTHERN LAKES BY SATURDAY FOLLOWED BY
ANOTHER COLD FRONT SATURDAY NIGHT INTO SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ONLY MADE MINOR CHANGES TO THE FORECAST AT THIS TIME.
STRONG 5H JET MOVING UP THE OHIO RIVER VALLEY THIS MORNING. THE
LOW PRESSURE THAT IS OVER SOUTHERN INDIANA WILL CONTINUE TO DEEPEN
AS IT LIFTS NORTH-NORTHEAST THROUGH THE AFTERNOON. AT THIS POINT
THE BETTER LIFT ON THE LEFT FRONT QUAD OF THE JET HAS KEPT MOST OF
THE SHOWERS OVER INDIANA. IT STILL APPEARS THERE WILL BE A LINE OF
LOW TOPPED SHOWERS/THUNDERSTORMS THAT WILL RACE ACROSS THE AREA
NEAR THE COLD FRONT LATE THIS AFTERNOON INTO THE EVENING.
WE WILL CONTINUE TO MONITOR THE LOCATION OF THE LOW LEVEL JET
THAT SHOULD INCREASE THROUGH THE AFTERNOON AS IT LIFTS NORTHWARD
ACROSS CENTRAL OHIO. THE CORE OF THE LOW LEVEL JET LOOKS AS IF IT
WILL BE SLIGHTLY FURTHER EAST THAN PREVIOUS THINKING. WE WILL DIG
INTO THE NEW MODEL RUNS AS THEY ARRIVE AND TWEAK THE WIND
ADVISORY/WARNINGS IF NEEDED.
PREVIOUS DISCUSSION...
THE STORM SYSTEM THAT HAS BEEN ADVERTISED FOR THE LAST WEEK HAS
FINALLY ARRIVED. THE STORM SYSTEM IS PROGGED TO MOVE NORTH OUT OF
THE TENNESSEE VALLEY AREA INTO WESTERN OHIO AND WESTERN LAKE ERIE BY
THIS EVENING. THE MAIN PROBLEM WITH THE SYSTEM WILL BE THE STRONG
DAMAGING WINDS ASSOCIATED WITH THE SYSTEM. STRONG LOW LEVEL JET AND
PRESSURE RISE/FALL COUPLET ALONG THE COLD FRONT WILL ALLOW SOME OF
THE STRONGER WINDS ALOFT TO REACH THE SURFACE. THE WINDOW FOR THE
STRONG WINDS APPEARS THAT IT WILL BE A FAIRLY NARROW TIME FRAME FROM
LATE THIS AFTERNOON THROUGH THURSDAY MORNING. WINDS OF 20 TO 35 MPH
WITH GUSTS AS HIGH AS 60 MPH ARE EXPECTED IN THE WESTERN PORTIONS OF
THE FORECAST AREA AND ALONG THE NORTHEAST LAKE SHORE. SLIGHTLY LOWER
WINDS AND WIND GUSTS ARE EXPECTED ELSEWHERE. THEREFORE...A HIGH
WIND WARNING HAS BEEN ISSUED FOR THE WEST HALF AND IMMEDIATE LAKE
SHORE IN THE NORTHEAST. A WIND ADVISORY HAS BEEN ISSUED FOR THE
REST OF THE EASTERN AREAS.
NEXT PROBLEM IS HOW MUCH RAIN ARE WE GOING TO DEAL WITH. SOME
INDICATIONS ARE THAT THE SHOWERS MAY HOLD OFF UNTIL THIS EVENING
OVER MUCH OF THE AREA. HOWEVER...LATEST RADAR AND HRRR MODEL SUGGEST
SOME SCATTERED SHOWER ACTIVITY THROUGH THE DAY. STORM SYSTEM AND
COLD FRONT SHOULD BRING ANOTHER SWATH OF MOISTURE INTO THE REGION
THIS MORNING AND AGAIN THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
OVERALL UPPER LEVEL PATTERN IS PROGRESSIVE AND FAST MOVING. UPPER
LEVEL TROUGH THAT GENERATED THE CURRENT STORM SYSTEM WILL QUICKLY
CAUSE SURFACE LOW PRESSURE SYSTEM TO QUICKLY VACATE THE AREA ON
THURSDAY. ACTUALLY...SOME WARM AIR ADVECTION IS EXPECTED TO DEVELOP
LATER IN THE DAY ON THURSDAY. THIS SHOULD HELP TO BOOST THE
TEMPERATURES POSSIBLY BACK TO THE LOWER 40S.
SYNOPTIC PRECIPITATION FOR THE MOST PART IS EXPECTED TO PULL OUT TO
THE NORTHEAST FAIRLY QUICKLY WITH THE STORM SYSTEM ON THURSDAY. SOME
LINGERING LAKE EFFECT RAIN/SNOW SHOWERS IS POSSIBLE THURSDAY BEFORE
ENDING.
NEXT STORM SYSTEM APPROACHES THE AREA AND IT WILL MAKE ITS PRESENCE
KNOWN FAIRLY QUICKLY AS EARLY AS SATURDAY. A STORM SYSTEM WILL MOVE
EAST INTO THE WESTERN GREAT LAKES AND DRAG A COLD FRONT ACROSS THE
REGION BY SATURDAY NIGHT. MILD TEMPERATURES SHOULD KEEP
PRECIPITATION IN THE FORM OF RAIN THROUGH THE PERIOD. NOT EXPECTING
ANY MAJOR COOL DOWNS THROUGH MUCH OF THE UPCOMING LAST WEEK OF THE
NEW YEAR. HOWEVER...MODELS ARE HINTING AT A FAIRLY MAJOR COLD AIR
OUT BREAK JUST IN TIME FOR THE NEW YEAR TO ARRIVE. SO FAR THIS LOOKS
TO BE COLDEST AIR OF THE SEASON. DEPENDING ON WHICH MODEL YOU LOOK
AT...THE COLD AIR TAKES A GLANCING BLOW WHILE THE OTHER MODEL SLOWS
THE COLD AIR EXITING OUR AREA.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
THE EXTENDED IS NOT CLEAR CUT. ON SUNDAY THE THREAT OF SNOW SHOWERS
WILL BE ENDING FROM THE NORTH AS HIGH PRESSURE BUILDS IN. THE ECMWF
IS SLOWER WITH THE PRECIPITATION DECREASE AND WARMER TO START. AT
THIS TIME KEPT THE THREAT JUST SNOW SHOWERS BUT THIS WILL HAVE TO BE
WATCHED. LATE MONDAY INTO TUESDAY THE MODELS BRING A LOW UP INTO THE
OHIO VALLEY. THE POPS MAY HAVE TO BE RAISED IF THE MODELS KEEP
SHOWING THIS TREND. WENT CLOSE TO WPC GUIDANCE FOR THE TEMPERATURE
FORECAST.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
A STRONG AND DEEPENING LOW MOVES ALONG THE OHIO AND INDIANA
BORDER THIS AFTERNOON AND EVENING....LOOK FOR MOSTLY MVFR
CONDITIONS THIS AFTERNOON AND EVENING.
THE FRONT ASSOCIATED WITH THE LOW SWEEPS ACROSS THE AREA LATE
THIS EVENING. SOME SHOWERS AND ISOLATED THUNDERSTORMS COULD
ACCOMPANY THE FRONT...FOR SOME OF THE TAFS...I MENTIONED VCTS
FOR KMFD...KCAK AND KYNG AT THIS TIME.
SOME STRONG WINDS WILL OCCUR WITH THE FRONTAL PASSAGE AND THEN
WINDS WILL GUST TO 40 TO 45 KNOTS BEHIND THE FRONT FOR A FEW HOURS
WITH ISOLATED GUSTS TO 50 KNOTS WILL ALSO BE POSSIBLE. A DRY SLOT
WILL OCCUR AFTER THE FRONTAL PASSAGE AND THEN A NARROW BAND OF
MAINLY SNOW SHOWERS WILL OCCUR LATE TONIGHT. AT THIS TIME IT SEEMS
LIKELY IT WILL BE COLD ENOUGH FOR JUST SNOW TOWARDS MORNING. THE
VISIBILITY MAY DROP LOWER THEN 3SM FOR A BRIEF TIME.
.OUTLOOK...NON-VFR LIKELY THURSDAY. NON-VFR DEVELOPING AGAIN
SATURDAY AND CONTINUING SUNDAY.
&&
.MARINE...
WINDS WILL BE ON THE INCREASE ON THE LAKE ESPECIALLY THIS AFTERNOON
AFTER THE LOW MOVES NORTH AND THE COLD FRONT MOVES THROUGH. SOME
QUESTION ON THE EXACT TIMING OF WHEN THE GALE FORCE WINDS WILL
START. WILL HAVE THE GALE WARNING START ON THE WEST END AT 22Z AND
ON THE EAST END AT 02Z. WE ALSO COULD HAVE A SQUALL LINE MOVE
THROUGH LATE THIS AFTERNOON AND EVENING WITH HIGH WINDS. THE LOW
MOVES QUICK SO THIS WILL BE A QUICK SHOT OF GALE FORCE WINDS. SOME
CONCERN WITH THE 925 MB WINDS ON THE LAKE OVER 50 KNOTS...THE COLD
ADVECTION IS SOMEWHAT GRADUAL SO GOING WITH SUSTAINED OF 40 TO 45
KNOTS WITH HIGHER GUSTS. BECAUSE OF THE GALE FORCE WINDS THE WATER
LEVEL WILL DROP ON THE WEST END OF THE LAKE LATE THIS EVENING...A
LOW WATER ADVISORY WILL BE ISSUED. ONCE THE GALE DECREASE LATE
THURSDAY A SMALL CRAFT ADVISORY WILL BE NEEDED ON THE EAST END.
A MODERATE SOUTHWEST FLOW WILL CONTINUE ON THE LAKE FOR FRIDAY AND
SATURDAY. IT IS IN WARM ADVECTION SO WE MAY NOT NEED A SMALL CRAFT
ADVISORY ON THE LAKE. A COLD FRONT MOVES THROUGH LATE SATURDAY AND
WE MAY NEED A SMALL CRAFT ADVISORY ON THE EAST END OF THE LAKE IN
THE COLD ADVECTION. IT WILL BE SHORT LIVED AS HIGH PRESSURE BUILDS
IN QUICKLY ON SUNDAY. FOR EARLY NEXT WEEK THE FLOW ON THE LAKE WILL
BE EAST AND LIGHT AND LOW PRESSURE MOVES THROUGH THE OHIO VALLEY AND
HIGH PRESSURE IS OVER CANADA.
&&
.CLIMATE...
TEMPERATURES TODAY WILL ATTEMPT TO SURGE INTO THE 60S AND MAY
APPROACH RECORD LEVELS. THE CURRENT RECORDS ARE:
CLEVELAND 65 1964 AKRON-CANTON 63 1964
ERIE 66 1964 MANSFIELD 62 1964
TOLEDO 65 1889 YOUNGSTOWN 63 1982
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...HIGH WIND WARNING FROM 7 PM THIS EVENING TO 10 AM EST THURSDAY
FOR OHZ012-089.
WIND ADVISORY FROM 7 PM THIS EVENING TO 10 AM EST THURSDAY FOR
OHZ013-014-021>023-031>033-038.
HIGH WIND WARNING UNTIL 4 AM EST THURSDAY FOR OHZ003-006>011-
017>020-027>030-036-037-047.
PA...HIGH WIND WARNING FROM 7 PM THIS EVENING TO 10 AM EST THURSDAY
FOR PAZ001.
WIND ADVISORY FROM 7 PM THIS EVENING TO 10 AM EST THURSDAY FOR
PAZ002-003.
MARINE...GALE WARNING FROM 9 PM THIS EVENING TO 4 PM EST THURSDAY FOR
LEZ061-145>149-165>169.
LOW WATER ADVISORY FROM 9 PM THIS EVENING TO NOON EST THURSDAY
FOR LEZ142>144-162>164.
GALE WARNING FROM 5 PM THIS AFTERNOON TO 10 AM EST THURSDAY
FOR LEZ142>144-162>164.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...LOMBARDY/MULLEN
SHORT TERM...LOMBARDY
LONG TERM...KIELTYKA
AVIATION...BC
MARINE...KIELTYKA
CLIMATE...
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1014 AM EST WED DEC 24 2014
.SYNOPSIS...
LOW PRESSURE WILL MOVE NORTH OUT OF THE TENNESSEE VALLEY TODAY TO
OHIO AND LAKE ERIE BY THIS EVENING. A TRAILING COLD FRONT WILL SWEEP
EAST ACROSS THE REGION THIS EVENING. STRONG GUSTY WINDS ARE EXPECTED
WITH THIS STORM SYSTEM ACROSS THE AREA. A RIDGE OF HIGH PRESSURE
WILL BUILD NORTH INTO THE REGION BY THURSDAY EVENING. LOW PRESSURE
WILL BUILD NORTHEAST INTO THE NORTHERN LAKES BY SATURDAY FOLLOWED BY
ANOTHER COLD FRONT SATURDAY NIGHT INTO SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ONLY MADE MINOR CHANGES TO THE FORECAST AT THIS TIME.
STRONG 5H JET MOVING UP THE OHIO RIVER VALLEY THIS MORNING. THE
LOW PRESSURE THAT IS OVER SOUTHERN INDIANA WILL CONTINUE TO DEEPEN
AS IT LIFTS NORTH-NORTHEAST THROUGH THE AFTERNOON. AT THIS POINT
THE BETTER LIFT ON THE LEFT FRONT QUAD OF THE JET HAS KEPT MOST OF
THE SHOWERS OVER INDIANA. IT STILL APPEARS THERE WILL BE A LINE OF
LOW TOPPED SHOWERS/THUNDERSTORMS THAT WILL RACE ACROSS THE AREA
NEAR THE COLD FRONT LATE THIS AFTERNOON INTO THE EVENING.
WE WILL CONTINUE TO MONITOR THE LOCATION OF THE LOW LEVEL JET
THAT SHOULD INCREASE THROUGH THE AFTERNOON AS IT LIFTS NORTHWARD
ACROSS CENTRAL OHIO. THE CORE OF THE LOW LEVEL JET LOOKS AS IF IT
WILL BE SLIGHTLY FURTHER EAST THAN PREVIOUS THINKING. WE WILL DIG
INTO THE NEW MODEL RUNS AS THEY ARRIVE AND TWEAK THE WIND
ADVISORY/WARNINGS IF NEEDED.
PREVIOUS DISCUSSION...
THE STORM SYSTEM THAT HAS BEEN ADVERTISED FOR THE LAST WEEK HAS
FINALLY ARRIVED. THE STORM SYSTEM IS PROGGED TO MOVE NORTH OUT OF
THE TENNESSEE VALLEY AREA INTO WESTERN OHIO AND WESTERN LAKE ERIE BY
THIS EVENING. THE MAIN PROBLEM WITH THE SYSTEM WILL BE THE STRONG
DAMAGING WINDS ASSOCIATED WITH THE SYSTEM. STRONG LOW LEVEL JET AND
PRESSURE RISE/FALL COUPLET ALONG THE COLD FRONT WILL ALLOW SOME OF
THE STRONGER WINDS ALOFT TO REACH THE SURFACE. THE WINDOW FOR THE
STRONG WINDS APPEARS THAT IT WILL BE A FAIRLY NARROW TIME FRAME FROM
LATE THIS AFTERNOON THROUGH THURSDAY MORNING. WINDS OF 20 TO 35 MPH
WITH GUSTS AS HIGH AS 60 MPH ARE EXPECTED IN THE WESTERN PORTIONS OF
THE FORECAST AREA AND ALONG THE NORTHEAST LAKE SHORE. SLIGHTLY LOWER
WINDS AND WIND GUSTS ARE EXPECTED ELSEWHERE. THEREFORE...A HIGH
WIND WARNING HAS BEEN ISSUED FOR THE WEST HALF AND IMMEDIATE LAKE
SHORE IN THE NORTHEAST. A WIND ADVISORY HAS BEEN ISSUED FOR THE
REST OF THE EASTERN AREAS.
NEXT PROBLEM IS HOW MUCH RAIN ARE WE GOING TO DEAL WITH. SOME
INDICATIONS ARE THAT THE SHOWERS MAY HOLD OFF UNTIL THIS EVENING
OVER MUCH OF THE AREA. HOWEVER...LATEST RADAR AND HRRR MODEL SUGGEST
SOME SCATTERED SHOWER ACTIVITY THROUGH THE DAY. STORM SYSTEM AND
COLD FRONT SHOULD BRING ANOTHER SWATH OF MOISTURE INTO THE REGION
THIS MORNING AND AGAIN THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
OVERALL UPPER LEVEL PATTERN IS PROGRESSIVE AND FAST MOVING. UPPER
LEVEL TROUGH THAT GENERATED THE CURRENT STORM SYSTEM WILL QUICKLY
CAUSE SURFACE LOW PRESSURE SYSTEM TO QUICKLY VACATE THE AREA ON
THURSDAY. ACTUALLY...SOME WARM AIR ADVECTION IS EXPECTED TO DEVELOP
LATER IN THE DAY ON THURSDAY. THIS SHOULD HELP TO BOOST THE
TEMPERATURES POSSIBLY BACK TO THE LOWER 40S.
SYNOPTIC PRECIPITATION FOR THE MOST PART IS EXPECTED TO PULL OUT TO
THE NORTHEAST FAIRLY QUICKLY WITH THE STORM SYSTEM ON THURSDAY. SOME
LINGERING LAKE EFFECT RAIN/SNOW SHOWERS IS POSSIBLE THURSDAY BEFORE
ENDING.
NEXT STORM SYSTEM APPROACHES THE AREA AND IT WILL MAKE ITS PRESENCE
KNOWN FAIRLY QUICKLY AS EARLY AS SATURDAY. A STORM SYSTEM WILL MOVE
EAST INTO THE WESTERN GREAT LAKES AND DRAG A COLD FRONT ACROSS THE
REGION BY SATURDAY NIGHT. MILD TEMPERATURES SHOULD KEEP
PRECIPITATION IN THE FORM OF RAIN THROUGH THE PERIOD. NOT EXPECTING
ANY MAJOR COOL DOWNS THROUGH MUCH OF THE UPCOMING LAST WEEK OF THE
NEW YEAR. HOWEVER...MODELS ARE HINTING AT A FAIRLY MAJOR COLD AIR
OUT BREAK JUST IN TIME FOR THE NEW YEAR TO ARRIVE. SO FAR THIS LOOKS
TO BE COLDEST AIR OF THE SEASON. DEPENDING ON WHICH MODEL YOU LOOK
AT...THE COLD AIR TAKES A GLANCING BLOW WHILE THE OTHER MODEL SLOWS
THE COLD AIR EXITING OUR AREA.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
THE EXTENDED IS NOT CLEAR CUT. ON SUNDAY THE THREAT OF SNOW SHOWERS
WILL BE ENDING FROM THE NORTH AS HIGH PRESSURE BUILDS IN. THE ECMWF
IS SLOWER WITH THE PRECIPITATION DECREASE AND WARMER TO START. AT
THIS TIME KEPT THE THREAT JUST SNOW SHOWERS BUT THIS WILL HAVE TO BE
WATCHED. LATE MONDAY INTO TUESDAY THE MODELS BRING A LOW UP INTO THE
OHIO VALLEY. THE POPS MAY HAVE TO BE RAISED IF THE MODELS KEEP
SHOWING THIS TREND. WENT CLOSE TO WPC GUIDANCE FOR THE TEMPERATURE
FORECAST.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
THIS MORNING SOME PATCHES OF LOW CLOUDS...DRIZZLE AND FOG WILL BE
MOVING THROUGH AS A STRONG AND DEEPENING LOW MOVES ALONG THE OHIO
AND INDIANA BORDER THIS AFTERNOON. SOME QUESTION WHETHER CONDITIONS
IMPROVE TO JUST MVFR OR POSSIBLY VFR UNTIL THE FRONT ASSOCIATED
WITH THE LOW SWEEPS ACROSS THE AREA LATE THIS AFTERNOON AND
EVENING. WITH THE FRONT SOME SHOWERS AND ISOLATED THUNDERSTORMS
COULD ACCOMPANY IT. CONFIDENCE IT TOO LOW TO DECIDE WHICH TAF
SITES WOULD HAVE THE THUNDER. SOME STRONG WINDS COULD ALSO OCCUR
WITH THE FRONTAL PASSAGE AND THEN WINDS WILL GUST TO 40 TO 45
KNOTS BEHIND THE FRONT FOR A FEW HOURS WITH ISOLATED GUSTS TO 50
KNOTS WILL ALSO BE POSSIBLE. A DRY SLOT WILL OCCUR AFTER THE
FRONTAL PASSAGE AND THEN A NARROW BAND OF MAINLY SNOW SHOWERS WILL
OCCUR LATE TONIGHT. AT THIS TIME IT SEEMS LIKE IT WILL BE COLD
ENOUGH FOR JUST SNOW. THE VISIBILITY MAY DROP LOWER THEN 3SM FOR A
BRIEF TIME.
.OUTLOOK...NON-VFR LIKELY INTO THURSDAY. NON-VFR DEVELOPING AGAIN
SATURDAY AND CONTINUING SUNDAY.
&&
.MARINE...
WINDS WILL BE ON THE INCREASE ON THE LAKE ESPECIALLY THIS AFTERNOON
AFTER THE LOW MOVES NORTH AND THE COLD FRONT MOVES THROUGH. SOME
QUESTION ON THE EXACT TIMING OF WHEN THE GALE FORCE WINDS WILL
START. WILL HAVE THE GALE WARNING START ON THE WEST END AT 22Z AND
ON THE EAST END AT 02Z. WE ALSO COULD HAVE A SQUALL LINE MOVE
THROUGH LATE THIS AFTERNOON AND EVENING WITH HIGH WINDS. THE LOW
MOVES QUICK SO THIS WILL BE A QUICK SHOT OF GALE FORCE WINDS. SOME
CONCERN WITH THE 925 MB WINDS ON THE LAKE OVER 50 KNOTS...THE COLD
ADVECTION IS SOMEWHAT GRADUAL SO GOING WITH SUSTAINED OF 40 TO 45
KNOTS WITH HIGHER GUSTS. BECAUSE OF THE GALE FORCE WINDS THE WATER
LEVEL WILL DROP ON THE WEST END OF THE LAKE LATE THIS EVENING...A
LOW WATER ADVISORY WILL BE ISSUED. ONCE THE GALE DECREASE LATE
THURSDAY A SMALL CRAFT ADVISORY WILL BE NEEDED ON THE EAST END.
A MODERATE SOUTHWEST FLOW WILL CONTINUE ON THE LAKE FOR FRIDAY AND
SATURDAY. IT IS IN WARM ADVECTION SO WE MAY NOT NEED A SMALL CRAFT
ADVISORY ON THE LAKE. A COLD FRONT MOVES THROUGH LATE SATURDAY AND
WE MAY NEED A SMALL CRAFT ADVISORY ON THE EAST END OF THE LAKE IN
THE COLD ADVECTION. IT WILL BE SHORT LIVED AS HIGH PRESSURE BUILDS
IN QUICKLY ON SUNDAY. FOR EARLY NEXT WEEK THE FLOW ON THE LAKE WILL
BE EAST AND LIGHT AND LOW PRESSURE MOVES THROUGH THE OHIO VALLEY AND
HIGH PRESSURE IS OVER CANADA.
&&
.CLIMATE...
TEMPERATURES TODAY WILL ATTEMPT TO SURGE INTO THE 60S AND MAY
APPROACH RECORD LEVELS. THE CURRENT RECORDS ARE:
CLEVELAND 65 1964 AKRON-CANTON 63 1964
ERIE 66 1964 MANSFIELD 62 1964
TOLEDO 65 1889 YOUNGSTOWN 63 1982
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...HIGH WIND WARNING FROM 7 PM THIS EVENING TO 10 AM EST THURSDAY
FOR OHZ012-089.
WIND ADVISORY FROM 7 PM THIS EVENING TO 10 AM EST THURSDAY FOR
OHZ013-014-021>023-031>033-038.
HIGH WIND WARNING FROM 3 PM THIS AFTERNOON TO 4 AM EST
THURSDAY FOR OHZ003-006>011-017>020-027>030-036-037-047.
PA...HIGH WIND WARNING FROM 7 PM THIS EVENING TO 10 AM EST THURSDAY
FOR PAZ001.
WIND ADVISORY FROM 7 PM THIS EVENING TO 10 AM EST THURSDAY FOR
PAZ002-003.
MARINE...GALE WARNING FROM 9 PM THIS EVENING TO 4 PM EST THURSDAY FOR
LEZ061-145>149-165>169.
LOW WATER ADVISORY FROM 9 PM THIS EVENING TO NOON EST THURSDAY
FOR LEZ142>144-162>164.
GALE WARNING FROM 5 PM THIS AFTERNOON TO 10 AM EST THURSDAY
FOR LEZ142>144-162>164.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...LOMBARDY/MULLEN
SHORT TERM...LOMBARDY
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
CLIMATE...
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
658 AM EST WED DEC 24 2014
.SYNOPSIS...
LOW PRESSURE WILL MOVE NORTH OUT OF THE TENNESSEE VALLEY TODAY TO
OHIO AND LAKE ERIE BY THIS EVENING. A TRAILING COLD FRONT WILL SWEEP
EAST ACROSS THE REGION THIS EVENING. STRONG GUSTY WINDS ARE EXPECTED
WITH THIS STORM SYSTEM ACROSS THE AREA. A RIDGE OF HIGH PRESSURE
WILL BUILD NORTH INTO THE REGION BY THURSDAY EVENING. LOW PRESSURE
WILL BUILD NORTHEAST INTO THE NORTHERN LAKES BY SATURDAY FOLLOWED BY
ANOTHER COLD FRONT SATURDAY NIGHT INTO SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MINOR CHANGES TO REDUCE PRECIPITATION TO CHANCE POPS FOR THIS
MORNING. NEXT SURGE OF SHOWER ACTIVITY WILL COME THIS AFTERNOON
AS LOW PRESSURE SYSTEM PASSES OVER THE REGION AND COLD FRONT
SWEEPS EAST.
TEMPERATURES CONTINUE TO HOLD NEARLY STEADY AND SHOULD BEGIN TO
SLOWLY CLIMB AFTER SUNRISE.
PREVIOUS DISCUSSION...
THE STORM SYSTEM THAT HAS BEEN ADVERTISED FOR THE LAST WEEK HAS
FINALLY ARRIVED. THE STORM SYSTEM IS PROGGED TO MOVE NORTH OUT OF
THE TENNESSEE VALLEY AREA INTO WESTERN OHIO AND WESTERN LAKE ERIE BY
THIS EVENING. THE MAIN PROBLEM WITH THE SYSTEM WILL BE THE STRONG
DAMAGING WINDS ASSOCIATED WITH THE SYSTEM. STRONG LOW LEVEL JET AND
PRESSURE RISE/FALL COUPLET ALONG THE COLD FRONT WILL ALLOW SOME OF
THE STRONGER WINDS ALOFT TO REACH THE SURFACE. THE WINDOW FOR THE
STRONG WINDS APPEARS THAT IT WILL BE A FAIRLY NARROW TIME FRAME FROM
LATE THIS AFTERNOON THROUGH THURSDAY MORNING. WINDS OF 20 TO 35 MPH
WITH GUSTS AS HIGH AS 60 MPH ARE EXPECTED IN THE WESTERN PORTIONS OF
THE FORECAST AREA AND ALONG THE NORTHEAST LAKE SHORE. SLIGHTLY LOWER
WINDS AND WIND GUSTS ARE EXPECTED ELSEWHERE. THEREFORE...A HIGH
WIND WARNING HAS BEEN ISSUED FOR THE WEST HALF AND IMMEDIATE LAKE
SHORE IN THE NORTHEAST. A WIND ADVISORY HAS BEEN ISSUED FOR THE
REST OF THE EASTERN AREAS.
NEXT PROBLEM IS HOW MUCH RAIN ARE WE GOING TO DEAL WITH. SOME
INDICATIONS ARE THAT THE SHOWERS MAY HOLD OFF UNTIL THIS EVENING
OVER MUCH OF THE AREA. HOWEVER...LATEST RADAR AND HRRR MODEL SUGGEST
SOME SCATTERED SHOWER ACTIVITY THROUGH THE DAY. STORM SYSTEM AND
COLD FRONT SHOULD BRING ANOTHER SWATH OF MOISTURE INTO THE REGION
THIS MORNING AND AGAIN THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
OVERALL UPPER LEVEL PATTERN IS PROGRESSIVE AND FAST MOVING. UPPER
LEVEL TROUGH THAT GENERATED THE CURRENT STORM SYSTEM WILL QUICKLY
CAUSE SURFACE LOW PRESSURE SYSTEM TO QUICKLY VACATE THE AREA ON
THURSDAY. ACTUALLY...SOME WARM AIR ADVECTION IS EXPECTED TO DEVELOP
LATER IN THE DAY ON THURSDAY. THIS SHOULD HELP TO BOOST THE
TEMPERATURES POSSIBLY BACK TO THE LOWER 40S.
SYNOPTIC PRECIPITATION FOR THE MOST PART IS EXPECTED TO PULL OUT TO
THE NORTHEAST FAIRLY QUICKLY WITH THE STORM SYSTEM ON THURSDAY. SOME
LINGERING LAKE EFFECT RAIN/SNOW SHOWERS IS POSSIBLE THURSDAY BEFORE
ENDING.
NEXT STORM SYSTEM APPROACHES THE AREA AND IT WILL MAKE ITS PRESENCE
KNOWN FAIRLY QUICKLY AS EARLY AS SATURDAY. A STORM SYSTEM WILL MOVE
EAST INTO THE WESTERN GREAT LAKES AND DRAG A COLD FRONT ACROSS THE
REGION BY SATURDAY NIGHT. MILD TEMPERATURES SHOULD KEEP
PRECIPITATION IN THE FORM OF RAIN THROUGH THE PERIOD. NOT EXPECTING
ANY MAJOR COOL DOWNS THROUGH MUCH OF THE UPCOMING LAST WEEK OF THE
NEW YEAR. HOWEVER...MODELS ARE HINTING AT A FAIRLY MAJOR COLD AIR
OUT BREAK JUST IN TIME FOR THE NEW YEAR TO ARRIVE. SO FAR THIS LOOKS
TO BE COLDEST AIR OF THE SEASON. DEPENDING ON WHICH MODEL YOU LOOK
AT...THE COLD AIR TAKES A GLANCING BLOW WHILE THE OTHER MODEL SLOWS
THE COLD AIR EXITING OUR AREA.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
THE EXTENDED IS NOT CLEAR CUT. ON SUNDAY THE THREAT OF SNOW SHOWERS
WILL BE ENDING FROM THE NORTH AS HIGH PRESSURE BUILDS IN. THE ECMWF
IS SLOWER WITH THE PRECIPITATION DECREASE AND WARMER TO START. AT
THIS TIME KEPT THE THREAT JUST SNOW SHOWERS BUT THIS WILL HAVE TO BE
WATCHED. LATE MONDAY INTO TUESDAY THE MODELS BRING A LOW UP INTO THE
OHIO VALLEY. THE POPS MAY HAVE TO BE RAISED IF THE MODELS KEEP
SHOWING THIS TREND. WENT CLOSE TO WPC GUIDANCE FOR THE TEMPERATURE
FORECAST.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
THIS MORNING SOME PATCHES OF LOW CLOUDS...DRIZZLE AND FOG WILL BE
MOVING THROUGH AS A STRONG AND DEEPENING LOW MOVES ALONG THE OHIO
AND INDIANA BORDER THIS AFTERNOON. SOME QUESTION WHETHER CONDITIONS
IMPROVE TO JUST MVFR OR POSSIBLY VFR UNTIL THE FRONT ASSOCIATED
WITH THE LOW SWEEPS ACROSS THE AREA LATE THIS AFTERNOON AND
EVENING. WITH THE FRONT SOME SHOWERS AND ISOLATED THUNDERSTORMS
COULD ACCOMPANY IT. CONFIDENCE IT TOO LOW TO DECIDE WHICH TAF
SITES WOULD HAVE THE THUNDER. SOME STRONG WINDS COULD ALSO OCCUR
WITH THE FRONTAL PASSAGE AND THEN WINDS WILL GUST TO 40 TO 45
KNOTS BEHIND THE FRONT FOR A FEW HOURS WITH ISOLATED GUSTS TO 50
KNOTS WILL ALSO BE POSSIBLE. A DRY SLOT WILL OCCUR AFTER THE
FRONTAL PASSAGE AND THEN A NARROW BAND OF MAINLY SNOW SHOWERS WILL
OCCUR LATE TONIGHT. AT THIS TIME IT SEEMS LIKE IT WILL BE COLD
ENOUGH FOR JUST SNOW. THE VISIBILITY MAY DROP LOWER THEN 3SM FOR A
BRIEF TIME.
.OUTLOOK...NON-VFR LIKELY INTO THURSDAY. NON-VFR DEVELOPING AGAIN
SATURDAY AND CONTINUING SUNDAY.
&&
.MARINE...
WINDS WILL BE ON THE INCREASE ON THE LAKE ESPECIALLY THIS AFTERNOON
AFTER THE LOW MOVES NORTH AND THE COLD FRONT MOVES THROUGH. SOME
QUESTION ON THE EXACT TIMING OF WHEN THE GALE FORCE WINDS WILL
START. WILL HAVE THE GALE WARNING START ON THE WEST END AT 22Z AND
ON THE EAST END AT 02Z. WE ALSO COULD HAVE A SQUALL LINE MOVE
THROUGH LATE THIS AFTERNOON AND EVENING WITH HIGH WINDS. THE LOW
MOVES QUICK SO THIS WILL BE A QUICK SHOT OF GALE FORCE WINDS. SOME
CONCERN WITH THE 925 MB WINDS ON THE LAKE OVER 50 KNOTS...THE COLD
ADVECTION IS SOMEWHAT GRADUAL SO GOING WITH SUSTAINED OF 40 TO 45
KNOTS WITH HIGHER GUSTS. BECAUSE OF THE GALE FORCE WINDS THE WATER
LEVEL WILL DROP ON THE WEST END OF THE LAKE LATE THIS EVENING...A
LOW WATER ADVISORY WILL BE ISSUED. ONCE THE GALE DECREASE LATE
THURSDAY A SMALL CRAFT ADVISORY WILL BE NEEDED ON THE EAST END.
A MODERATE SOUTHWEST FLOW WILL CONTINUE ON THE LAKE FOR FRIDAY AND
SATURDAY. IT IS IN WARM ADVECTION SO WE MAY NOT NEED A SMALL CRAFT
ADVISORY ON THE LAKE. A COLD FRONT MOVES THROUGH LATE SATURDAY AND
WE MAY NEED A SMALL CRAFT ADVISORY ON THE EAST END OF THE LAKE IN
THE COLD ADVECTION. IT WILL BE SHORT LIVED AS HIGH PRESSURE BUILDS
IN QUICKLY ON SUNDAY. FOR EARLY NEXT WEEK THE FLOW ON THE LAKE WILL
BE EAST AND LIGHT AND LOW PRESSURE MOVES THROUGH THE OHIO VALLEY AND
HIGH PRESSURE IS OVER CANADA.
&&
.CLIMATE...
TEMPERATURES TODAY WILL ATTEMPT TO SURGE INTO THE 60S AND MAY
APPROACH RECORD LEVELS. THE CURRENT RECORDS ARE:
CLEVELAND 65 1964 AKRON-CANTON 63 1964
ERIE 66 1964 MANSFIELD 62 1964
TOLEDO 65 1889 YOUNGSTOWN 63 1982
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...HIGH WIND WARNING FROM 7 PM THIS EVENING TO 10 AM EST THURSDAY
FOR OHZ012-089.
WIND ADVISORY FROM 7 PM THIS EVENING TO 10 AM EST THURSDAY FOR
OHZ013-014-021>023-031>033-038.
HIGH WIND WARNING FROM 3 PM THIS AFTERNOON TO 4 AM EST
THURSDAY FOR OHZ003-006>011-017>020-027>030-036-037-047.
PA...HIGH WIND WARNING FROM 7 PM THIS EVENING TO 10 AM EST THURSDAY
FOR PAZ001.
WIND ADVISORY FROM 7 PM THIS EVENING TO 10 AM EST THURSDAY FOR
PAZ002-003.
MARINE...GALE WARNING FROM 9 PM THIS EVENING TO 4 PM EST THURSDAY FOR
LEZ061-145>149-165>169.
LOW WATER ADVISORY FROM 9 PM THIS EVENING TO NOON EST THURSDAY
FOR LEZ142>144-162>164.
GALE WARNING FROM 5 PM THIS AFTERNOON TO 10 AM EST THURSDAY
FOR LEZ142>144-162>164.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...LOMBARDY
SHORT TERM...LOMBARDY
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
CLIMATE...
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
418 AM EST WED DEC 24 2014
.SYNOPSIS...
LOW PRESSURE WILL MOVE NORTH OUT OF THE TENNESSEE VALLEY TODAY TO
OHIO AND LAKE ERIE BY THIS EVENING. A TRAILING COLD FRONT WILL SWEEP
EAST ACROSS THE REGION THIS EVENING. STRONG GUSTY WINDS ARE EXPECTED
WITH THIS STORM SYSTEM ACROSS THE AREA. A RIDGE OF HIGH PRESSURE
WILL BUILD NORTH INTO THE REGION BY THURSDAY EVENING. LOW PRESSURE
WILL BUILD NORTHEAST INTO THE NORTHERN LAKES BY SATURDAY FOLLOWED BY
ANOTHER COLD FRONT SATURDAY NIGHT INTO SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE STORM SYSTEM THAT HAS BEEN ADVERTISED FOR THE LAST WEEK HAS
FINALLY ARRIVED. THE STORM SYSTEM IS PROGGED TO MOVE NORTH OUT OF
THE TENNESSEE VALLEY AREA INTO WESTERN OHIO AND WESTERN LAKE ERIE BY
THIS EVENING. THE MAIN PROBLEM WITH THE SYSTEM WILL BE THE STRONG
DAMAGING WINDS ASSOCIATED WITH THE SYSTEM. STRONG LOW LEVEL JET AND
PRESSURE RISE/FALL COUPLET ALONG THE COLD FRONT WILL ALLOW SOME OF
THE STRONGER WINDS ALOFT TO REACH THE SURFACE. THE WINDOW FOR THE
STRONG WINDS APPEARS THAT IT WILL BE A FAIRLY NARROW TIME FRAME FROM
LATE THIS AFTERNOON THROUGH THURSDAY MORNING. WINDS OF 20 TO 35 MPH
WITH GUSTS AS HIGH AS 60 MPH ARE EXPECTED IN THE WESTERN PORTIONS OF
THE FORECAST AREA AND ALONG THE NORTHEAST LAKE SHORE. SLIGHTLY LOWER
WINDS AND WIND GUSTS ARE EXPECTED ELSEWHERE. THEREFORE...A HIGH
WIND WARNING HAS BEEN ISSUED FOR THE WEST HALF AND IMMEDIATE LAKE
SHORE IN THE NORTHEAST. A WIND ADVISORY HAS BEEN ISSUED FOR THE
REST OF THE EASTERN AREAS.
NEXT PROBLEM IS HOW MUCH RAIN ARE WE GOING TO DEAL WITH. SOME
INDICATIONS ARE THAT THE SHOWERS MAY HOLD OFF UNTIL THIS EVENING
OVER MUCH OF THE AREA. HOWEVER...LATEST RADAR AND HRRR MODEL SUGGEST
SOME SCATTERED SHOWER ACTIVITY THROUGH THE DAY. STORM SYSTEM AND
COLD FRONT SHOULD BRING ANOTHER SWATH OF MOISTURE INTO THE REGION
THIS MORNING AND AGAIN THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
OVERALL UPPER LEVEL PATTERN IS PROGRESSIVE AND FAST MOVING. UPPER
LEVEL TROUGH THAT GENERATED THE CURRENT STORM SYSTEM WILL QUICKLY
CAUSE SURFACE LOW PRESSURE SYSTEM TO QUICKLY VACATE THE AREA ON
THURSDAY. ACTUALLY...SOME WARM AIR ADVECTION IS EXPECTED TO DEVELOP
LATER IN THE DAY ON THURSDAY. THIS SHOULD HELP TO BOOST THE
TEMPERATURES POSSIBLY BACK TO THE LOWER 40S.
SYNOPTIC PRECIPITATION FOR THE MOST PART IS EXPECTED TO PULL OUT TO
THE NORTHEAST FAIRLY QUICKLY WITH THE STORM SYSTEM ON THURSDAY. SOME
LINGERING LAKE EFFECT RAIN/SNOW SHOWERS IS POSSIBLE THURSDAY BEFORE
ENDING.
NEXT STORM SYSTEM APPROACHES THE AREA AND IT WILL MAKE ITS PRESENCE
KNOWN FAIRLY QUICKLY AS EARLY AS SATURDAY. A STORM SYSTEM WILL MOVE
EAST INTO THE WESTERN GREAT LAKES AND DRAG A COLD FRONT ACROSS THE
REGION BY SATURDAY NIGHT. MILD TEMPERATURES SHOULD KEEP
PRECIPITATION IN THE FORM OF RAIN THROUGH THE PERIOD. NOT EXPECTING
ANY MAJOR COOL DOWNS THROUGH MUCH OF THE UPCOMING LAST WEEK OF THE
NEW YEAR. HOWEVER...MODELS ARE HINTING AT A FAIRLY MAJOR COLD AIR
OUT BREAK JUST IN TIME FOR THE NEW YEAR TO ARRIVE. SO FAR THIS LOOKS
TO BE COLDEST AIR OF THE SEASON. DEPENDING ON WHICH MODEL YOU LOOK
AT...THE COLD AIR TAKES A GLANCING BLOW WHILE THE OTHER MODEL SLOWS
THE COLD AIR EXITING OUR AREA.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
THE EXTENDED IS NOT CLEAR CUT. ON SUNDAY THE THREAT OF SNOW SHOWERS
WILL BE ENDING FROM THE NORTH AS HIGH PRESSURE BUILDS IN. THE ECMWF
IS SLOWER WITH THE PRECIPITATION DECREASE AND WARMER TO START. AT
THIS TIME KEPT THE THREAT JUST SNOW SHOWERS BUT THIS WILL HAVE TO BE
WATCHED. LATE MONDAY INTO TUESDAY THE MODELS BRING A LOW UP INTO THE
OHIO VALLEY. THE POPS MAY HAVE TO BE RAISED IF THE MODELS KEEP
SHOWING THIS TREND. WENT CLOSE TO WPC GUIDANCE FOR THE TEMPERATURE
FORECAST.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
THE LOWEST IFR CEILINGS AND VISIBILITIES WILL LIKELY OCCUR ACROSS
NORTHWEST OHIO THIS MORNING WITH AREAS IF IFR CEILINGS AND VSBY
ACROSS NE OH AND NW PA AS THE WARM FRONT SLOWLY LIFTS NORTH. WE
SHOULD BREAK INTO THE WARM SECTOR ON WEDNESDAY WITH AN INCREASING
SOUTH WIND AND CEILINGS AND VISIBILITIES SLOWLY IMPROVING. A STRONG
COLD FRONT WILL CROSS THE AREA FROM WEST TO EAST LATE WED
AFTERNOON/EVENING WITH SOUTH SOUTHWEST WIND GUSTS 35 TO 40 KNOTS
(OR MORE) INTO WEDNESDAY NIGHT.
.OUTLOOK...NON-VFR LIKELY INTO THURSDAY. NON-VFR DEVELOPING AGAIN
SATURDAY CONTINUING SUNDAY.
&&
.MARINE...
WINDS WILL BE ON THE INCREASE ON THE LAKE ESPECIALLY THIS AFTERNOON
AFTER THE LOW MOVES NORTH AND THE COLD FRONT MOVES THROUGH. SOME
QUESTION ON THE EXACT TIMING OF WHEN THE GALE FORCE WINDS WILL
START. WILL HAVE THE GALE WARNING START ON THE WEST END AT 22Z AND
ON THE EAST END AT 02Z. WE ALSO COULD HAVE A SQUALL LINE MOVE
THROUGH LATE THIS AFTERNOON AND EVENING WITH HIGH WINDS. THE LOW
MOVES QUICK SO THIS WILL BE A QUICK SHOT OF GALE FORCE WINDS. SOME
CONCERN WITH THE 925 MB WINDS ON THE LAKE OVER 50 KNOTS...THE COLD
ADVECTION IS SOMEWHAT GRADUAL SO GOING WITH SUSTAINED OF 40 TO 45
KNOTS WITH HIGHER GUSTS. BECAUSE OF THE GALE FORCE WINDS THE WATER
LEVEL WILL DROP ON THE WEST END OF THE LAKE LATE THIS EVENING...A
LOW WATER ADVISORY WILL BE ISSUED. ONCE THE GALE DECREASE LATE
THURSDAY A SMALL CRAFT ADVISORY WILL BE NEEDED ON THE EAST END.
A MODERATE SOUTHWEST FLOW WILL CONTINUE ON THE LAKE FOR FRIDAY AND
SATURDAY. IT IS IN WARM ADVECTION SO WE MAY NOT NEED A SMALL CRAFT
ADVISORY ON THE LAKE. A COLD FRONT MOVES THROUGH LATE SATURDAY AND
WE MAY NEED A SMALL CRAFT ADVISORY ON THE EAST END OF THE LAKE IN
THE COLD ADVECTION. IT WILL BE SHORT LIVED AS HIGH PRESSURE BUILDS
IN QUICKLY ON SUNDAY. FOR EARLY NEXT WEEK THE FLOW ON THE LAKE WILL
BE EAST AND LIGHT AND LOW PRESSURE MOVES THROUGH THE OHIO VALLEY AND
HIGH PRESSURE IS OVER CANADA.
&&
.CLIMATE...
TEMPERATURES TODAY WILL ATTEMPT TO SURGE INTO THE 60S AND MAY
APPROACH RECORD LEVELS. THE CURRENT RECORDS ARE:
CLEVELAND 65 1964 AKRON-CANTON 63 1964
ERIE 66 1964 MANSFIELD 62 1964
TOLEDO 65 1889 YOUNGSTOWN 63 1982
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...HIGH WIND WARNING FROM 7 PM THIS EVENING TO 10 AM EST THURSDAY
FOR OHZ012-089.
WIND ADVISORY FROM 7 PM THIS EVENING TO 10 AM EST THURSDAY FOR
OHZ013-014-021>023-031>033-038.
HIGH WIND WARNING FROM 3 PM THIS AFTERNOON TO 4 AM EST
THURSDAY FOR OHZ003-006>011-017>020-027>030-036-037-047.
PA...HIGH WIND WARNING FROM 7 PM THIS EVENING TO 10 AM EST THURSDAY
FOR PAZ001.
WIND ADVISORY FROM 7 PM THIS EVENING TO 10 AM EST THURSDAY FOR
PAZ002-003.
MARINE...GALE WARNING FROM 9 PM THIS EVENING TO 4 PM EST THURSDAY FOR
LEZ061-145>149-165>169.
LOW WATER ADVISORY FROM 9 PM THIS EVENING TO NOON EST THURSDAY
FOR LEZ142>144-162>164.
GALE WARNING FROM 5 PM THIS AFTERNOON TO 10 AM EST THURSDAY
FOR LEZ142>144-162>164.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...LOMBARDY
SHORT TERM...LOMBARDY
LONG TERM...KIELTYKA
AVIATION...KOSARIK
MARINE...KIELTYKA
CLIMATE...MULLEN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
515 PM EST WED DEC 24 2014
.SYNOPSIS...
AN INTENSIFYING STORM SYSTEM OVER WESTERN OHIO WILL MOVE UP
THROUGH THE EASTERN GREAT LAKES THIS EVENING...DRAGGING A COLD
FRONT THROUGH THE REGION OVERNIGHT. GUSTY WEST WINDS WILL DEVELOP
BEHIND THE FRONT LATE TONIGHT AND THURSDAY. ANOTHER LESS POTENT
COLD FRONT WILL MOVE ACROSS THE AREA THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
REGIONAL RADAR SHOWS A LARGE-DISORGANIZED SHIELD OF RAIN
EXTENDING ALL WAY DOWN INTO THE CAROLINAS. THE MAIN THRUST REMAINS
OFF TO THE NORTHEAST WITH THE LATEST HRRR SUGGESTING THE BEST
CHANCES FOR RAIN INTO THE EVENING BEING FROM CENTRAL PA
EASTWARD...WITH MORE IN THE WAY OF A SPOTTY LIGHT RAIN OR SHOWERS
EXPECTED OVER MY WESTERN ZONES. NOT MUCH REASON TO EXPECT OTHER
THAN A CONTINUATION OF A DREARY CHRISTMAS EVE WITH PERIODS OF RAIN
AND AREAS OF FOG.
THE COLD FRONT SHOULD BE ENTERING MY WESTERN ZONES BETWEEN ABOUT 6
AND 9 PM...AND THEN IS EXPECTED TO SPEED ACROSS THE FORECAST AREA
TO BE EXITING MY FAR EASTERN ZONES BY THE PRE DAWN HOURS OF
CHRISTMAS MORNING. THE FRONT WILL BE ACCOMPANIED BY SOME
MARGINALLY STEEP MID LEVEL LAPSE RATES WHICH COULD LEAD TO A
RUMBLE OR TWO OF THUNDER ACCOMPANYING THE SYSTEM AS IT RACES
THROUGH. EARLIER EXPECTATIONS OF SOME SORT OF NARROW COLD FRONTAL
RAIN BAND-SQUALL LINE FEATURE IS BEING DOWNPLAYED IN THE LATEST
HIGH RES MODEL GUIDANCE WHICH SHOWS A GENERAL AREA OF SHOWERS
MOVING ACROSS THE REGION THIS EVENING ALONG AND AHEAD OF THE
FRONT. THIS SHOULD DIMINISH THE THREAT OF STRONG WINDS ALOFT
BEING TRANSFERRED DOWN IN THE CONVECTION.
TEMPS WILL STAY STEADY OR EVEN CLIMB AS THE FRONT ENTERS THE
REGION THIS EVENING HELPING MIX UP THE COOL AIR DAMMED BOUNDARY
LAYER.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
CHRISTMAS DAY WILL BRING A TRANSITION INTO A PRETTY TYPICAL POST
FRONTAL COOL SEASON PATTERN...WITH CLOUDS AND BLUSTERY GUSTY
WESTERLY WINDS. HIGHER ELEVATIONS WILL LIKELY SEE WINDS AS HIGH AS
35-45 MPH...WITH THE REST OF US MAINLY EXPERIENCING WINDS IN THE
20-30 MPH RANGE.
THE USUAL SCATTERED MAINLY HIGHER ELEVATION SNOW SHOWERS WILL BE
THE FEATURED CONDITIONS...WITH THE CENTRAL RIDGE-VALLEY REGION
SEEING LITTLE MORE THAN A PASSING LIGHT RAIN OR SNOW SHOWER. THE
POST FRONTAL AIR IS NOT REALLY VERY COLD SO EVEN WHERE THE MAIN
PRECIPITATION TYPE IS EXPECTED TO BE SNOW...TEMPERATURES ABOVE
FREEZING WILL KEEP ANY ACCUMULATIONS ON THE INSIGNIFICANT SIDE.
TEMPS WILL BE STEADY OR SLOWLY FALLING FOR MUCH OF THE DAY
THURSDAY...AFTER THE INITIAL DROP OF 10F OR SO IMMEDIATELY
FOLLOWING THE CFROPA VERY EARLY ON.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
POTENT LONGWAVE UPPER TROF EXITING THE EAST COAST AT THE START OF
THE PERIOD WILL BE REPLACED BY UPPER RIDGING INTO THE WEEKEND. AS
LONGWAVE UPPER TROFFING IS FORECAST TO DEVELOP OVER THE WRN US
STARTING EARLY IN THE PD AND NRN STREAM ENERGY RETREATS INTO
EASTERN CANADA...MDT TO STRONG SWRLY FLOW ALOFT IS THEN FORECAST
TO DOMINATE THE EASTERN CONUS FROM LATE IN THE WEEKEND THROUGH THE
REMAINDER OF THE YEAR.
MEDIUM RANGE GUIDANCE IS FAIRLY CONSISTENT ESPECIALLY EARLY IN
THE PERIOD...BUT THEN SOME DIFFERENCES ARISE IN 500MB FLOW
PATTERN AFTER MONDAY AS THE ECMWF MOVES ENERGY EAST FASTER...WHILE
THE GFS CLOSES OFF AN UPPER LOW OVER THE DESERT SW.
A NORTHERN STREAM WAVE IS FORECAST TO SUPPORT A COLD FRONT MOVING
EAST ACROSS THE STATE LATE IN THE WEEKEND...POSSIBLY STALLING
NEAR THE MASON DIXON LINE INTO MONDAY AS IT ENCOUNTERS RESISTANCE
FROM THE BUILDING UPPER FLOW. THIS FRONT LOOKS TO BE THE MAIN
FOCUS FOR PCPN IN THE LONG TERM PERIOD. WITH SNOW TO THE NORTH AND
WEST...AND A MIX TO RAIN ACROSS THE SOUTH.
WITH RIDGING OR SWRLY FLOW ALOFT MUCH OF THE PERIOD WILL FEATURE
ABOVE NORMAL TEMPS...WITH A COOL DOWN TOWARD NORMAL BY NEW YEARS
EVE.
&&
.AVIATION /22Z WEDNESDAY THROUGH MONDAY/...
THE MAIN CONCERNS REMAIN LIFR TO MVFR CONDITIONS AND LLWS
THIS EVENING.
HOWEVER...WATCHING LINE OF STORMS WEST OF PA. SINCE WE ARE
AT LEAST 10 DEGREES COOLER AND DEWPOINTS LOWER...THINK ANY
REAL STRONG STORMS WILL WEAKEN AS THEY MOVE TOWARD CENTRAL
PA. WILL CONTINUE TO MONITOR.
21Z TAFS SENT.
EARLIER DISCUSSION BELOW.
WIDESPREAD MVFR/IFR WITH RAIN AND AREAS OF FOG WILL CONTINUE
INTO THE EVENING AS A STORM SYSTEM MOVES INTO THE EASTERN GREAT
LAKES THIS EVENING.
THE ASSOCIATED TRAILING COLD FRONT WILL PUSH THROUGH CENTRAL
PENNSYLVANIA TONIGHT. ISOLATED EMBEDDED THUNDERSTORMS CANNOT BE
RULED OUT ALONG THE FRONT. STRONG AND GUSTY WEST WINDS WILL
DEVELOP BEHIND THE FRONT TONIGHT AND THURSDAY.
INCLUDED LLWS FOR ALL TAF SITES AS WINDS ALOFT BEGIN TO INCREASE
AHEAD OF THE APPROACHING FRONTAL SYSTEM WHILE SFC WINDS REMAIN
RELATIVELY LIGHT OUT OF THE SE.
WESTERN HIGH TERRAIN TERMINALS WILL HOLD ONTO REDUCED CONDITIONS
THROUGH MUCH OF CHRISTMAS DAY AFTER WINDS SHIFT TO THE WEST
BEHIND THE COLD FRONT...WHILE CENTRAL AND EASTERN TERMINALS WILL
SEE CEILINGS IMPROVE TO THE 3000-5000` RANGE BY LATE TONIGHT OR
FAIRLY EARLY CHRISTMAS MORNING.
OUTLOOK...
FRI...FAIR AND MOSTLY VFR.
SAT...VFR.
SUN...MVFR TO IFR WITH SCATTERED RAIN SHOWERS.
MON...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL NOON EST THURSDAY FOR PAZ004>006-010>012-
017-018-024-033.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/GARTNER
AVIATION...LA CORTE/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
349 PM EST WED DEC 24 2014
.SYNOPSIS...
AN INTENSIFYING STORM SYSTEM OVER WESTERN OHIO WILL MOVE UP
THROUGH THE EASTERN GREAT LAKES THIS EVENING...DRAGGING A COLD
FRONT THROUGH THE REGION OVERNIGHT. GUSTY WEST WINDS WILL DEVELOP
BEHIND THE FRONT LATE TONIGHT AND THURSDAY. ANOTHER LESS POTENT
COLD FRONT WILL MOVE ACROSS THE AREA THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
REGIONAL RADAR SHOWS A LARGE-DISORGANIZED SHIELD OF RAIN
EXTENDING ALL WAY DOWN INTO THE CAROLINAS. THE MAIN THRUST REMAINS
OFF TO THE NORTHEAST WITH THE LATEST HRRR SUGGESTING THE BEST
CHANCES FOR RAIN INTO THE EVENING BEING FROM CENTRAL PA
EASTWARD...WITH MORE IN THE WAY OF A SPOTTY LIGHT RAIN OR SHOWERS
EXPECTED OVER MY WESTERN ZONES. NOT MUCH REASON TO EXPECT OTHER
THAN A CONTINUATION OF A DREARY CHRISTMAS EVE WITH PERIODS OF RAIN
AND AREAS OF FOG.
THE COLD FRONT SHOULD BE ENTERING MY WESTERN ZONES BETWEEN ABOUT 6
AND 9 PM...AND THEN IS EXPECTED TO SPEED ACROSS THE FORECAST AREA
TO BE EXITING MY FAR EASTERN ZONES BY THE PRE DAWN HOURS OF
CHRISTMAS MORNING. THE FRONT WILL BE ACCOMPANIED BY SOME
MARGINALLY STEEP MID LEVEL LAPSE RATES WHICH COULD LEAD TO A
RUMBLE OR TWO OF THUNDER ACCOMPANYING THE SYSTEM AS IT RACES
THROUGH. EARLIER EXPECTATIONS OF SOME SORT OF NARROW COLD FRONTAL
RAIN BAND-SQUALL LINE FEATURE IS BEING DOWNPLAYED IN THE LATEST
HIGH RES MODEL GUIDANCE WHICH SHOWS A GENERAL AREA OF SHOWERS
MOVING ACROSS THE REGION THIS EVENING ALONG AND AHEAD OF THE
FRONT. THIS SHOULD DIMINISH THE THREAT OF STRONG WINDS ALOFT
BEING TRANSFERRED DOWN IN THE CONVECTION.
TEMPS WILL STAY STEADY OR EVEN CLIMB AS THE FRONT ENTERS THE
REGION THIS EVENING HELPING MIX UP THE COOL AIR DAMMED BOUNDARY
LAYER.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
CHRISTMAS DAY WILL BRING A TRANSITION INTO A PRETTY TYPICAL POST
FRONTAL COOL SEASON PATTERN...WITH CLOUDS AND BLUSTERY GUSTY
WESTERLY WINDS. HIGHER ELEVATIONS WILL LIKELY SEE WINDS AS HIGH AS
35-45 MPH...WITH THE REST OF US MAINLY EXPERIENCING WINDS IN THE
20-30 MPH RANGE.
THE USUAL SCATTERED MAINLY HIGHER ELEVATION SNOW SHOWERS WILL BE
THE FEATURED CONDITIONS...WITH THE CENTRAL RIDGE-VALLEY REGION
SEEING LITTLE MORE THAN A PASSING LIGHT RAIN OR SNOW SHOWER. THE
POST FRONTAL AIR IS NOT REALLY VERY COLD SO EVEN WHERE THE MAIN
PRECIPITATION TYPE IS EXPECTED TO BE SNOW...TEMPERATURES ABOVE
FREEZING WILL KEEP ANY ACCUMULATIONS ON THE INSIGNIFICANT SIDE.
TEMPS WILL BE STEADY OR SLOWLY FALLING FOR MUCH OF THE DAY
THURSDAY...AFTER THE INITIAL DROP OF 10F OR SO IMMEDIATELY
FOLLOWING THE CFROPA VERY EARLY ON.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
POTENT LONGWAVE UPPER TROF EXITING THE EAST COAST AT THE START OF
THE PERIOD WILL BE REPLACED BY UPPER RIDGING INTO THE WEEKEND. AS
LONGWAVE UPPER TROFFING IS FORECAST TO DEVELOP OVER THE WRN US
STARTING EARLY IN THE PD AND NRN STREAM ENERGY RETREATS INTO
EASTERN CANADA...MDT TO STRONG SWRLY FLOW ALOFT IS THEN FORECAST
TO DOMINATE THE EASTERN CONUS FROM LATE IN THE WEEKEND THROUGH THE
REMAINDER OF THE YEAR.
MEDIUM RANGE GUIDANCE IS FAIRLY CONSISTENT ESPECIALLY EARLY IN
THE PERIOD...BUT THEN SOME DIFFERENCES ARISE IN 500MB FLOW
PATTERN AFTER MONDAY AS THE ECMWF MOVES ENERGY EAST FASTER...WHILE
THE GFS CLOSES OFF AN UPPER LOW OVER THE DESERT SW.
A NORTHERN STREAM WAVE IS FORECAST TO SUPPORT A COLD FRONT MOVING
EAST ACROSS THE STATE LATE IN THE WEEKEND...POSSIBLY STALLING
NEAR THE MASON DIXON LINE INTO MONDAY AS IT ENCOUNTERS RESISTANCE
FROM THE BUILDING UPPER FLOW. THIS FRONT LOOKS TO BE THE MAIN
FOCUS FOR PCPN IN THE LONG TERM PERIOD. WITH SNOW TO THE NORTH AND
WEST...AND A MIX TO RAIN ACROSS THE SOUTH.
WITH RIDGING OR SWRLY FLOW ALOFT MUCH OF THE PERIOD WILL FEATURE
ABOVE NORMAL TEMPS...WITH A COOL DOWN TOWARD NORMAL BY NEW YEARS
EVE.
&&
.AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
WIDESPREAD MVFR/IFR WITH RAIN AND AREAS OF FOG WILL CONTINUE
INTO THE EVENING AS A STORM SYSTEM MOVES INTO THE EASTERN GREAT
LAKES THIS EVENING.
THE ASSOCIATED TRAILING COLD FRONT WILL PUSH THROUGH CENTRAL
PENNSYLVANIA TONIGHT. ISOLATED EMBEDDED THUNDERSTORMS CANNOT BE
RULED OUT ALONG THE FRONT. STRONG AND GUSTY WEST WINDS WILL
DEVELOP BEHIND THE FRONT TONIGHT AND THURSDAY.
INCLUDED LLWS FOR ALL TAF SITES AS WINDS ALOFT BEGIN TO INCREASE
AHEAD OF THE APPROACHING FRONTAL SYSTEM WHILE SFC WINDS REMAIN
RELATIVELY LIGHT OUT OF THE SE.
WESTERN HIGH TERRAIN TERMINALS WILL HOLD ONTO REDUCED CONDITIONS
THROUGH MUCH OF CHRISTMAS DAY AFTER WINDS SHIFT TO THE WEST
BEHIND THE COLD FRONT...WHILE CENTRAL AND EASTERN TERMINALS WILL
SEE CEILINGS IMPROVE TO THE 3000-5000` RANGE BY LATE TONIGHT OR
FAIRLY EARLY CHRISTMAS MORNING.
OUTLOOK...
FRI...FAIR AND MOSTLY VFR.
SAT...VFR.
SUN...MVFR TO IFR WITH SCATTERED RAIN SHOWERS.
MON...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 8 PM THIS EVENING TO NOON EST THURSDAY FOR
PAZ004>006-010>012-017-018-024-033.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/GARTNER
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
151 PM EST WED DEC 24 2014
.SYNOPSIS...
AN INTENSIFYING STORM SYSTEM OVER WESTERN OHIO AROUND MID DAY WILL
MOVE UP THROUGH THE EASTERN GREAT LAKES THIS EVENING...DRAGGING A
COLD FRONT THROUGH THE REGION OVERNIGHT. GUSTY WEST WINDS WILL
DEVELOP BEHIND THE FRONT LATE TONIGHT AND THURSDAY. ANOTHER LESS
POTENT COLD FRONT WILL MOVE ACROSS THE AREA THIS WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
REGIONAL RADAR SHOWS A LARGE-DISORGANIZED SHIELD OF RAIN
EXTENDING ALL WAY DOWN INTO THE CAROLINAS. THE MAIN THRUST REMAINS
OFF TO THE NORTHEAST WITH THE LATEST HRRR SUGGESTING THE BEST
CHANCES FOR RAIN INTO THE EVENING BEING FROM CENTRAL PA
EASTWARD...WITH MORE IN THE WAY OF A SPOTTY LIGHT RAIN OR SHOWERS
EXPECTED OVER MY WESTERN ZONES. NOT MUCH REASON TO EXPECT OTHER
THAN A CONTINUATION OF A DREARY CHRISTMAS EVE WITH PERIODS OF RAIN
AND AREAS OF FOG.
THE COLD FRONT SHOULD BE ENTERING MY WESTERN ZONES BETWEEN ABOUT 6
AND 9 PM...AND THEN IS EXPECTED TO SPEED ACROSS THE FORECAST AREA
TO BE EXITING MY FAR EASTERN ZONES BY THE PRE DAWN HOURS OF
CHRISTMAS MORNING. THE FRONT WILL BE ACCOMPANIED BY SOME
MARGINALLY STEEP MID LEVEL LAPSE RATES WHICH COULD LEAD TO A
RUMBLE OR TWO OF THUNDER ACCOMPANYING THE SYSTEM AS IT RACES
THROUGH. EARLIER EXPECTATIONS OF SOME SORT OF NARROW COLD FRONTAL
RAIN BAND-SQUALL LINE FEATURE IS BEING DOWNPLAYED IN THE LATEST
HIGH RES MODEL GUIDANCE WHICH SHOWS A GENERAL AREA OF SHOWERS
MOVING ACROSS THE REGION THIS EVENING ALONG AND AHEAD OF THE
FRONT. THIS SHOULD DIMINISH THE THREAT OF STRONG WINDS ALOFT
BEING TRANSFERRED DOWN IN THE CONVECTION.
TEMPS WILL STAY STEADY OR EVEN CLIMB AS THE FRONT ENTERS THE
REGION THIS EVENING HELPING MIX UP THE COOL AIR DAMMED BOUNDARY
LAYER.
&&
.SHORT TERM /THURSDAY/...
CHRISTMAS DAY WILL BRING A TRANSITION INTO A PRETTY TYPICAL POST
FRONTAL COOL SEASON PATTERN...WITH CLOUDS AND BLUSTERY GUSTY
WESTERLY WINDS. HIGHER ELEVATIONS WILL LIKELY SEE WINDS AS HIGH AS
35-45 MPH...WITH THE REST OF US MAINLY EXPERIENCING WINDS IN THE
20-30 MPH RANGE.
THE USUAL SCATTERED MAINLY HIGHER ELEVATION SNOW SHOWERS WILL BE
THE FEATURED CONDITIONS...WITH THE CENTRAL RIDGE-VALLEY REGION
SEEING LITTLE MORE THAN A PASSING LIGHT RAIN OR SNOW SHOWER. THE
POST FRONTAL AIR IS NOT REALLY VERY COLD SO EVEN WHERE THE MAIN
PRECIPITATION TYPE IS EXPECTED TO BE SNOW...TEMPERATURES ABOVE
FREEZING WILL KEEP ANY ACCUMULATIONS ON THE INSIGNIFICANT SIDE.
TEMPS WILL BE STEADY OR SLOWLY FALLING FOR MUCH OF THE DAY
THURSDAY...AFTER THE INITIAL DROP OF 10F OR SO IMMEDIATELY
FOLLOWING THE CFROPA VERY EARLY ON.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
MORE TRANQUIL WEATHER DEVELOPING FOR THURSDAY NIGHT AND FRIDAY...
WITH SW FLOW.
DID UP TEMPS FRIDAY INTO SAT...GIVEN RISING HEIGHTS.
CUT BACK PCPN FOR LATE FRIDAY.
12Z EC RUN HAS SYSTEM FURTHER NW NOW...BUT FOR NOW WENT WITH
SLIGHT CHC OF SNOW FROM SUNDAY INTO EARLY MONDAY MORNING.
AGAIN WITH SPLIT FLOW...THERE COULD BE SOME CHANCE FOR A SOUTHERN
WAVE TO BRING SOME RAIN OR SNOW SHOWERS TO THE AREA AT TIMES...BUT
IT LOOKS LIKE ANYTHING WOULD BE FAST MOVING. PERHAPS A CHANGE
LATER NEXT WEEK...AS CROSS POLAR FLOW SETS UP.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
WIDESPREAD MVFR/IFR WITH RAIN AND AREAS OF FOG WILL CONTINUE
INTO THE EVENING AS A STORM SYSTEM MOVES INTO THE EASTERN GREAT
LAKES THIS EVENING.
THE ASSOCIATED TRAILING COLD FRONT WILL PUSH THROUGH CENTRAL
PENNSYLVANIA TONIGHT. ISOLATED EMBEDDED THUNDERSTORMS CANNOT BE
RULED OUT ALONG THE FRONT. STRONG AND GUSTY WEST WINDS WILL
DEVELOP BEHIND THE FRONT TONIGHT AND THURSDAY.
INCLUDED LLWS FOR ALL TAF SITES AS WINDS ALOFT BEGIN TO INCREASE
AHEAD OF THE APPROACHING FRONTAL SYSTEM WHILE SFC WINDS REMAIN
RELATIVELY LIGHT OUT OF THE SE.
WESTERN HIGH TERRAIN TERMINALS WILL HOLD ONTO REDUCED CONDITIONS
THROUGH MUCH OF CHRISTMAS DAY AFTER WINDS SHIFT TO THE WEST
BEHIND THE COLD FRONT...WHILE CENTRAL AND EASTERN TERMINALS WILL
SEE CEILINGS IMPROVE TO THE 3000-5000` RANGE BY LATE TONIGHT OR
FAIRLY EARLY CHRISTMAS MORNING.
OUTLOOK...
FRI...FAIR AND MOSTLY VFR.
SAT...VFR.
SUN...MVFR TO IFR WITH SCATTERED RAIN SHOWERS.
MON...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 8 PM THIS EVENING TO NOON EST THURSDAY FOR
PAZ004>006-010>012-017-018-024-033.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/MARTIN
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1153 PM EST TUE DEC 23 2014
.SYNOPSIS...
AN INTENSIFYING STORM SYSTEM WILL MOVE NORTHWARD FROM THE WESTERN
GULF COAST TO THE CENTRAL GREAT LAKES BY WEDNESDAY EVENING. THE
ASSOCIATED COLD FRONT WILL PUSH THROUGH CENTRAL PENNSYLVANIA
WEDNESDAY NIGHT. ANOTHER LESS POTENT COLD FRONT WILL MOVE ACROSS
THE AREA THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
DEEP SOUTHERLY FLOW IN ADVANCE OF TROUGH OVR THE PLAINS HAS DRAWN
A PLUME OF GULF OF MEX MOISTURE OVER THE EASTERN CONUS.
SATL-DERIVED PWAT IMAGERY AS OF THIS EVENING IS SHOWING ANOMALOUS
DEEP LYR MOISTURE VALUES ACROSS THE ENTIRE E COAST. FOR THIS
EVENING...WEAK FORCING IN THE FORM OF OROGRAPHIC LIFT WILL PRODUCE
NO MORE THAN DRIZZLE OVR MOST OF CENTRAL PA. HOWEVER...REGIONAL
RADAR LOOP AT 03Z SHOWS A LARGE AREA OF RAIN LIFTING NORTH TOWARD
PA IN ASSOC WITH LL JET AHEAD OF DEVELOPING SFC LOW ON THE GULF
COAST. AS LL JET FEATURE LIFTS NORTH...EXPECT A STEADY RAIN TO
OVERSPREAD THE REGION FROM THE SOUTH OVERNIGHT.
RADAR TRENDS AND LATEST HRRR OUTPUT SUGGEST THE STEADY RAIN WILL
REACH THE S TIER COUNTIES ARND MIDNIGHT AND THE N TIER BY ARND 09Z.
A CALM WIND HAS PROMOTED WIDESPREAD FOG THIS EVENING. HOWEVER...AS
A SERLY BREEZE DEVELOPS LATE TONIGHT...EXPECT THE FOCUS OF THE FOG
TO BE ON THE RIDGES...WITH IMPROVING VSBYS ACROSS THE SUSQ VALLEY.
TEMPS EXPECTED TO REMAIN NEARLY STEADY OVERNIGHT...AVERAGING IN
THE L40S MOST PLACES.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
A RIBBON OF HIGHER DEEP LAYER MOISTURE WILL LIKELY BRING SOAKING
RAINFALL TO CENTRAL PA EARLY IN THE DAY. BY AFTN...MDL DATA
INDICATES THE RAIN SHOULD TAPER OFF AS DRY SLOT WORKS IN FROM
THE SW. LATEST GUIDANCE CONTINUES TO TARGET THE LOWER SUSQ VALLEY
FOR THE HEAVIEST RAIN...WITH 1+ INCH AMTS LIKELY BASED ON 21Z SREF
AND BLEND OF EARLIER OPER RUNS. MUCH LIGHTER AMTS EXPECTED ACROSS
THE NW MTNS.
HI RES MODELS INDICATING A SQUALL LINE TO ACCOMPANY SFC COLD
FRONT LAGGING THE UPPER FRONTAL PASSAGE WEDNESDAY EVENING. EXTENT
OF SURFACE DESTABILIZATION WILL ULTIMATELY DETERMINE HOW STRONG
THIS SQUALL LINE CAN GET...AND HOW STRONG WIND GUSTS CAN BE AT THE
SURFACE...BUT SUFFICE TO SAY ONE OF THE BETTER SEVERE WEATHER
SETUPS FOR CHRISTMAS EVE IS IN STORE FROM EARLY WED EVENING
THROUGH JUST PAST MIDNIGHT ACROSS CENTRAL PA. AS PREVIOUSLY
MENTIONED...EVEN MINIMAL CAPE COMBINED WITH STRONG /DEEP-LAYER
WIND FIELDS A FEW TO SVRL KFT AGL OFTEN RESULTS IN A NCFRB WITH
LOCALIZED DOWNBURST DAMAGE OCCURRING BENEATH MINI BOWS IN THE
LINE. SPC HAS PLACED MUCH OF CENTRAL PA IN MARGINAL CATEGORY FOR
DAY 2 AS A RESULT. MORE DETAILS BELOW.
TEMPERATURES WILL CLIMB INTO THE 50S WED AFTERNOON INTO WED
NIGHT...AS STRONGER SOUTHERLY WINDS DEVELOP. HAVE LOWERED DAYTIME
TEMPS OVR MUCH OF THE AREA...BASED ON LATEST GUIDANCE WHICH
INDICATES PERSISTENT COLD AIR DAMMING. THE WARMEST READINGS OVR
MUCH OF THE AREA MAY NOT BE REACHED UNTIL AFTER DARK WED EVENING.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
ANOMALOUSLY STRONG SSWRLY UPPER JET OF 140-150 KTS WILL ACCOMPANY
THE CFROPA IN THE 04-10Z TIME PERIOD CHRISTMAS DAY. IN
ADDITION...THE UNSEASONABLY WARM AND MOIST AIR WILL HELP TO
PRODUCE A RIBBON OF CAPE UP TO A FEW HUNDRED J/KG.
FOR NOW...HAVE CHC OF THUNDER IN FOR WED EVENING. NORMALLY I WOULD
BE MORE CONCERN ABOUT STRONG TO SEVERE STORMS...BUT BEST FORCING
ACROSS THE OH VLY. ALSO TIME OF DAY NOT THE BEST. HOWEVER...HINTS
OF COLD AIR DAMMING STILL ACROSS CENTRAL ZONES. EITHER
WAY...NORMALLY LIKE TO SEE DEWPTS IN THE UPPER 50S.
STILL EXPECT SOME GUSTY WINDS LATE WED NIGHT INTO THU AM...MOST
LIKELY WILL NEED A WIND ADVISORY...BUT STILL THIRD PERIOD.
TOOK SNOW OUT OF FCST FOR CHRISTMAS...TEMPS NOT COLD ENOUGH.
FRIDAY LOOKS NICE...WITH SW FLOW.
DID UP TEMPS FRIDAY INTO SAT...GIVEN RISING HEIGHTS.
CUT BACK PCPN FOR LATE FRIDAY.
12Z EC RUN HAS SYSTEM FURTHER NW NOW...BUT FOR NOW WENT WITH
SLIGHT CHC OF SNOW FROM SUNDAY INTO EARLY MONDAY MORNING.
AGAIN WITH SPLIT FLOW...THERE COULD BE SOME CHANCE FOR A SOUTHERN
WAVE TO BRING SOME RAIN OR SNOW SHOWERS TO THE AREA AT TIMES...BUT
IT LOOKS LIKE ANYTHING WOULD BE FAST MOVING. PERHAPS A CHANGE
LATER NEXT WEEK...AS CROSS POLAR FLOW SETS UP.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
WIDESPREAD REDUCTIONS IN FOG AND LOW CIGS WILL CONTINUE OVERNIGHT
WITH ENTIRE CWA REMAINING AT IFR/LIFR AS LOW LEVEL MOISTURE FEEDS
IN FROM THE SE FROM A WEAK SFC LOW EAST IF NEW JERSEY COAST...THEN
MAINTAINED AHEAD OF SRLY FLOW OF AN APPROACHING FRONTAL SYSTEM.
INCLUDED LLWS FOR ALL TAF SITES STARTING NEAR SUNRISE WED MORNING
AS WINDS ALOFT BEING TO INCREASE AHEAD OFF APPROACHING FRONTAL
SYSTEM OVER THE MIDWEST WHILE SFC WINDS REMAIN SERLY.
OUTLOOK...
WED...PERIODS OF RAIN ALONG WITH WIDESPREAD REDUCTIONS. SLGT CHC
TSTM NW. BREEZY. LLWS LIKELY.
THU...WINDY AND COLDER WITH SCT MVFR CIGS AND -SHSN. LLWS.
FRI...FAIR AND MOSTLY VFR.
SAT...FAIR AND MOSTLY VFR. SCT SHSN WITH LOCAL REDUCTIONS NW.
SUN...MVFR TO IFR WITH CHC RA/SN...ESP SOUTH.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR/MARTIN
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...MARTIN
AVIATION...GARTNER
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1150 AM CST WED DEC 24 2014
.UPDATE...
&&
.DISCUSSION...
&&
.PREV DISCUSSION... /ISSUED 1001 AM CST WED DEC 24 2014/
UPDATE...
CURRENT RADAR SHOWS RAIN/SHOWERS MOVING INTO NE PORTION OF OUR CWA.
WILL LOWER POPS OVER THE W/NW COUNTIES...BUT LATEST HRRR SUGGESTS
ONE MORE ROUND OF SCATTERED LIGHT SHOWERS THIS AFTERNOON SO WILL NOT
DROP POPS COMPLETELY. VISIBLE SATELLITE SHOWS A THIN ZONE OF
CLEARING APPROACHING WESTERN COUNTIES. CLEARING MAY BE SHORT-LIVED
AS ADDITIONAL CLOUD IS COVER WORKING ITS WAY EAST THROUGH ARKANSAS.
WILL MAKE MINOR ADJUSTMENTS TO SKY FOR THIS AFTERNOON. WILL HOLD OFF
ON ANY CHANGES TO LATER PERIODS UNTIL ALL 12Z GUIDANCE ARRIVES.
UPDATED FORECASTS/GRIDS OUT SHORTLY.
GW
PREV DISCUSSION... /ISSUED 318 AM CST WED DEC 24 2014/
DISCUSSION...
CURRENTLY A COLD FRONT WAS JUST EAST OF THE CWA WITH LIGHT
NORTHWEST WINDS AND TEMPERATURES GENERALLY IN THE MID AND UPPER
40S OVER THE AREA. RAIN...WITH A LIFTING SECOND WAVE IN THE
ARKLATEX...WAS BREAKING OUT OVER CENTRAL AND EASTERN
ARKANSAS. OTHERWISE POINTS EAST WERE CLOUDY WITH PATCHY FOG.
FOR TODAY AND TONIGHT...UPPER LEVEL TROUGH OVER THE OZARKS WILL
CONTINUE TO LIFT NORTHEAST THROUGH THE DAY AND SHEAR SOME AS IT
DOES. RAIN CHANCES WILL CONTINUE THIS MORNING THEN SLOWLY END FROM
SOUTHWEST TO NORTHEAST IN THE AFTERNOON. SKIES WILL BECOME PARTLY
CLOUDY LATE TONIGHT FROM WEST TO EAST. APPEARS THE GREATEST RISK
FOR PATCHY FOG WILL BE OVER THE EAST AFTER MIDNIGHT...WHERE
HEAVIER AMOUNTS OF RAIN FELL YESTERDAY.
CHRISTMAS DAY AND FRIDAY...NOT MUCH CHANGE NEEDED THIS PERIOD AS
MODELS SHOW THE UPPER FLOW STARTING OFF WESTERLY AND THEN QUICKLY
SHIFTING BACK SOUTHWESTERLY. LOW LEVELS WILL ALSO QUICKLY BECOME
SOUTHERLY WITH A FEW GUSTS STARTING CHRISTMAS AFTERNOON AND
PERSISTING THROUGH FRIDAY. A MIX OF CLOUDS AND SUN SHOULD BUMP
TEMPERATURES INTO THE 50S THURSDAY...AND WITH STRONGER WAA FRIDAY
MAYBE THE LOWER 60S FOR SOME. THOUGH THERE MAY BE A STRAY SHOWER
WEST OF THE MS RIVER FRIDAY AFTERNOON BETTER MOISTURE IS PROGGED
TO COME INTO THE MIDSOUTH FRIDAY NIGHT. LOWS WILL ALSO BE MILDER.
SATURDAY AND SUNDAY...THE EURO AND GFS BOTH SHOW A MOIST UPPER
LEVEL FLOW OVER A PASSING COLD FRONT. THUS TEMPERATURES WILL
BECOME COOL AGAIN...SKIES CLOUDY AND RAIN REMAINING IN THE
FORECAST. A DISTINCT SHORTWAVE MOVING IN THE FLOW ON SUNDAY MAY
SPARK A FEW HEAVIER SHOWERS SOUTH OF INTERSTATE FORTY...BUT FOR
NOW LEFT OUT ANY MENTION OF THUNDER AS BY THIS TIME LIFT ALONG THE
FRONT WILL BE WELL TO OUR SOUTHEAST.
MONDAY AND TUESDAY...PRECIPITATION CHANCES WILL DIMINISH SOME THIS
PERIOD AS DEEPER ARCTIC AIR MOVES SOUTHEAST OUT OF THE CENTRAL
PLAINS. HIGH TEMPERATURES WILL RUN APPROXIMATELY FIVE DEGREES
BELOW NORMAL MONDAY...AND CLOSER TO TEN DEGREES BY TUESDAY. A
DISTURBANCE LATE TUESDAY MAY TRIGGER A THREAT FOR LIGHT SNOW OVER
THE NORTHERN HALF OF THE AREA...BUT THERE IS PLENTY OF TIME TO SEE
IF THIS THREAT WILL MATERIALIZE INTO ANYTHING.
JAB
AVIATION...
18Z TAF CYCLE
CIGS SHOULD IMPROVE SHORTLY AT MEM AND JBR AND THEN BKN TO OVC
DECK TO SPREAD BACK OVER MEM AND JBR AND PERSIST INTO THE
EVENING. MKL AND TUP SHOULD REMAIN BKN/OVC THIS AFTERNOON. WINDS
SHOULD BE WESTERLY THIS AFTERNOON.
TONIGHT, EXPECT CLOUDS TO THIN OUT WHILE WINDS VEER MORE.
FOG TO BE AROUND LAT TONIGHT INTO EARLY TMR MORNING.
MAINLY CLEAR SKIES AND SOUTHERLY WINDS WILL BE AROUND
CHRISTMAS MORNING.
WER
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1001 AM CST WED DEC 24 2014
.UPDATE...
CURRENT RADAR SHOWS RAIN/SHOWERS MOVING INTO NE PORTION OF OUR CWA.
WILL LOWER POPS OVER THE W/NW COUNTIES...BUT LATEST HRRR SUGGESTS
ONE MORE ROUND OF SCATTERED LIGHT SHOWERS THIS AFTERNOON SO WILL NOT
DROP POPS COMPLETELY. VISIBLE SATELLITE SHOWS A THIN ZONE OF
CLEARING APPROACHING WESTERN COUNTIES. CLEARING MAY BE SHORT-LIVED
AS ADDITIONAL CLOUD IS COVER WORKING ITS WAY EAST THROUGH ARKANSAS.
WILL MAKE MINOR ADJUSTMENTS TO SKY FOR THIS AFTERNOON. WILL HOLD OFF
ON ANY CHANGES TO LATER PERIODS UNTIL ALL 12Z GUIDANCE ARRIVES.
UPDATED FORECASTS/GRIDS OUT SHORTLY.
GW
&&
.PREV DISCUSSION... /ISSUED 318 AM CST WED DEC 24 2014/
DISCUSSION...
CURRENTLY A COLD FRONT WAS JUST EAST OF THE CWA WITH LIGHT
NORTHWEST WINDS AND TEMPERATURES GENERALLY IN THE MID AND UPPER
40S OVER THE AREA. RAIN...WITH A LIFTING SECOND WAVE IN THE
ARKLATEX...WAS BREAKING OUT OVER CENTRAL AND EASTERN
ARKANSAS. OTHERWISE POINTS EAST WERE CLOUDY WITH PATCHY FOG.
FOR TODAY AND TONIGHT...UPPER LEVEL TROUGH OVER THE OZARKS WILL
CONTINUE TO LIFT NORTHEAST THROUGH THE DAY AND SHEAR SOME AS IT
DOES. RAIN CHANCES WILL CONTINUE THIS MORNING THEN SLOWLY END FROM
SOUTHWEST TO NORTHEAST IN THE AFTERNOON. SKIES WILL BECOME PARTLY
CLOUDY LATE TONIGHT FROM WEST TO EAST. APPEARS THE GREATEST RISK
FOR PATCHY FOG WILL BE OVER THE EAST AFTER MIDNIGHT...WHERE
HEAVIER AMOUNTS OF RAIN FELL YESTERDAY.
CHRISTMAS DAY AND FRIDAY...NOT MUCH CHANGE NEEDED THIS PERIOD AS
MODELS SHOW THE UPPER FLOW STARTING OFF WESTERLY AND THEN QUICKLY
SHIFTING BACK SOUTHWESTERLY. LOW LEVELS WILL ALSO QUICKLY BECOME
SOUTHERLY WITH A FEW GUSTS STARTING CHRISTMAS AFTERNOON AND
PERSISTING THROUGH FRIDAY. A MIX OF CLOUDS AND SUN SHOULD BUMP
TEMPERATURES INTO THE 50S THURSDAY...AND WITH STRONGER WAA FRIDAY
MAYBE THE LOWER 60S FOR SOME. THOUGH THERE MAY BE A STRAY SHOWER
WEST OF THE MS RIVER FRIDAY AFTERNOON BETTER MOISTURE IS PROGGED
TO COME INTO THE MIDSOUTH FRIDAY NIGHT. LOWS WILL ALSO BE MILDER.
SATURDAY AND SUNDAY...THE EURO AND GFS BOTH SHOW A MOIST UPPER
LEVEL FLOW OVER A PASSING COLD FRONT. THUS TEMPERATURES WILL
BECOME COOL AGAIN...SKIES CLOUDY AND RAIN REMAINING IN THE
FORECAST. A DISTINCT SHORTWAVE MOVING IN THE FLOW ON SUNDAY MAY
SPARK A FEW HEAVIER SHOWERS SOUTH OF INTERSTATE FORTY...BUT FOR
NOW LEFT OUT ANY MENTION OF THUNDER AS BY THIS TIME LIFT ALONG THE
FRONT WILL BE WELL TO OUR SOUTHEAST.
MONDAY AND TUESDAY...PRECIPITATION CHANCES WILL DIMINISH SOME THIS
PERIOD AS DEEPER ARCTIC AIR MOVES SOUTHEAST OUT OF THE CENTRAL
PLAINS. HIGH TEMPERATURES WILL RUN APPROXIMATELY FIVE DEGREES
BELOW NORMAL MONDAY...AND CLOSER TO TEN DEGREES BY TUESDAY. A
DISTURBANCE LATE TUESDAY MAY TRIGGER A THREAT FOR LIGHT SNOW OVER
THE NORTHERN HALF OF THE AREA...BUT THERE IS PLENTY OF TIME TO SEE
IF THIS THREAT WILL MATERIALIZE INTO ANYTHING.
JAB
&&
.AVIATION...
12Z TAF CYCLE
IFR CIGS SHOULD PERSIST THIS MORNING INTO EARLY AFTERNOON AT
KMEM...KMKL...AND KTUP. NUMEROUS RAIN SHOWERS WILL ALSO CONTINUE
AT ALL SITES. MVFR CIGS WILL BE COMMON THIS MORNING AT KJBR. THERE
WILL BE A GRADUAL IMPROVEMENT TO MVFR CIGS LATER THIS AFTERNOON AT
ALL SITES WHICH SHOULD CONTINUE INTO THIS EVENING. WINDS WILL PICK
UP FROM THE NORTHWEST AND WEST TODAY AND GUST AT ALL TAF SITES.
MVFR CIGS WILL EVENTUALLY SCATTER OUT OVERNIGHT WITH RAIN ENDING
AND WINDS DIMINISHING. THIS MAY SET THE STAGE FOR SOME MVFR/IFR
VSBYS IN FOG LATE TONIGHT AT KMKL AND KTUP.
JLH
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
937 PM CST THU DEC 25 2014
.UPDATE...
SEE DISCUSSION FOR EVENING UPDATE.
&&
.DISCUSSION...
CLOUD COVER HAS STARTED TO INCREASE TOWARDS THE CRP AREA THIS
EVENING AND IS STILL ON TRACK TO EXPAND IN COVERAGE ACROSS OUR
AREA THIS EVENING. A WEDGE OF VORTICITY EMBEDDED IN A SHORTWAVE
IS FORECASTED TO MOVE ACROSS THE WATERS TONIGHT AND MOVE OVER THE
TX/ LA BORDER TOMORROW MORNING. MOISTURE VALUES ARE STILL LIMITED
BUT LATEST HRRR RUN HAS A LINE OF SHOWERS FORMING THANKS TO THE
LIFT AND MOVING INLAND. GFS AND NAM FORECAST SOUNDINGS DO HAVE A
SATURATED LAYER UP TO AROUND 800 MB THOUGH. DUE TO THIS HAVE MADE
MINOR CHANGES TO POP GRIDS TO ACCOUNT FOR POTENTIAL OF SOME
SHOWERS FORMING THIS MORNING FROM THE SHORTWAVE. TOMORROW
AFTERNOON MODELS ARE AGAIN SHOWING STREAMER SHOWERS AND CURRENT
FORECAST HAS THIS COVERED. BESIDES MINOR CHANGES TO POP GRIDS FOR
THIS MORNING NO OTHER CHANGES REQUIRED AT THIS TIME. CURRENT
FORECAST IS ON TRACK. 23
&&
.PREV DISCUSSION... /ISSUED 544 PM CST THU DEC 25 2014/
DISCUSSION...
SEE THE 00Z AVIATION DISCUSSION BELOW.
40
AVIATION...
INCREASING MOISTURE ADVECTION AND THE DEVELOPMENT OF A LOW-LEVEL
JET WILL HELP MVFR CEILINGS TO FORM LATER TONIGHT AND FRIDAY
MORNING...MAINLY BETWEEN 08Z AND 12Z. THERE WILL ALSO BE A CHANCE
FOR ISOLATED SHOWERS MAINLY AFTER 17Z. THE NAMBUFR FORECAST
SOUNDINGS ARE SUGGESTING IFR CONDITIONS MAY DEVELOP LATE IN THE
AFTERNOON.
40
PREV DISCUSSION... /ISSUED 301 PM CST THU DEC 25 2014/
DISCUSSION...
CLOUDS WILL CONTINUE TO INCREASE OVERNIGHT AS LOW LEVEL MOISTURE
IS DRAWN BACK INTO SOUTHEAST TEXAS. SOUTHERLY WINDS...WINDS AND
CLOUD COVER WILL PRODUCE TEMPERATURES ABOUT 15 TO 20 DEGREES
WARMER THAN LAST NIGHT. PW VALUES INCREASE TO AROUND 1.1 INCHES OF
FRIDAY AND FCST SOUNDINGS SHOW A SATURATED LAYER UP TO AROUND 800
MB. PROBABLY GET SOME STREAMER SHOWERS BENEATH THE CAP. A WEAK
UPPER LEVEL DISTURBANCE WILL KEEP RAIN IN THE FCST ON FRIDAY
NIGHT. A COLD FRONT WILL APPROACH SE TX ON SATURDAY. STILL SOME
TIMING DIFFERENCES WITH THE FRONT BUT AT THIS TIME...IT APPEARS
THE FRONT WILL MOVE THRU KCLL AROUND 15Z...KIAH AROUND 20Z AND
KGLS AROUND 00Z. DYNAMICS ON SATURDAY LOOKING A BIT BETTER WITH
CAPE VALUES NEAR 1500...LI`S -3 TO -5...TT`S IN THE LOWER 50S AND
K INDEX IN THE UPPER 30S. HELICITY VALUES ARE AROUND 200 AS WELL.
SE TX WILL ALSO GET LIFT ENHANCED FROM A DEPARTING 140 KT RRQ.
RAISED POPS A BIT ON SATURDAY AND WOULD NOT BE SURPRISED IF SOME
OF THE STORMS ON SATURDAY BECOME STRONG TO SEVERE. THE GFS AND
ECMWF CONTINUE TO PUSH THE WEAK UPPER LEVEL TROUGH OVER SW TX TO
THE EAST FASTER THAN THE NAM AND CANADIAN. POST FRONTAL RAINS WILL
CONTINUE SATURDAY NIGHT INTO EARLY SUNDAY AS SOUTHWEST WINDS ALOFT
OVER RIDE COOLER N-NE SFC WINDS. THE NAM/CANADIAN DIVERGE FROM THE
GFS/ECMWF ON SUNDAY WITH THE NAM/CAN HOLDING THE UPPER TROUGH TO
THE WEST AND MAINTAINING THE SW FLOW ALOFT. THE GFS/EC MOVE THE
TROUGH EASTWARD AND THE UPPER FLOW BECOMES ZONAL ENDING THE
ISENTROPIC LIFT. HAVE LEANED TOWARD THE GFS/ECMWF SOLUTION AND
FEEL RAIN WILL DIMINISH BY SUNDAY AFTN.
THERE SHOULD BE SOME BRIEF CLEARING MON/MON NITE BEFORE CLOUDS
RETURN ON TUESDAY AS THE NEXT UPPER TROUGH DROPS SOUTH INTO AZ.
THE FLOW ALOFT WILL ONCE AGAIN BECOME SOUTHWEST AND A COASTAL LOW
WILL DEVELOP EAST OF KBRO. THE COMBINATION OF THESE FEATURES
COUPLED WITH ADDITIONAL LIFT FROM THE SLOW MOVING UPPER LEVEL
TROUGH SHOULD YIELD PATCHY LIGHT RAIN EACH DAY THROUGH FRIDAY.
TEMPERATURES WILL BE ON THE COLD SIDE AS A 1040 MB HIGH SLIDES
SOUTH INTO THE SOUTHERN PLAINS ON WEDNESDAY AND ANOTHER 1040 HIGH
APPROACHES THE AREA NEXT FRIDAY. DESPITE THE COLD TEMPERATURES...
AT LEAST FOR NOW...IT APPEARS ALL THE PRECIPITATION WILL REMAIN
LIQUID. 43
MARINE...
A DEVELOPING SURFACE LOW IN THE LEE OF THE ROCKY MOUNTAINS WILL
ENCOURAGE ELEVATED ONSHORE FLOW TO CONTINUE INTO FRIDAY
MORNING...AND MARINERS IN SMALL CRAFT SHOULD EXERCISE CAUTION OVER
THE COASTAL WATERS TONIGHT. TEMPERATURES OVER THE SHALLOWER SHELF
WATERS ARE CURRENTLY AROUND 61 TO 63 DEGREES. WITH ONSHORE FLOW
CONTINUING TO ADVECT WARM...MOIST AIR OVER THESE COOLER
WATERS...THE POSSIBILITY EXISTS FOR SEA FOG DEVELOPMENT LATE
FRIDAY NIGHT INTO SATURDAY MORNING. THE LIMITING FACTOR FOR THIS
WILL BE THE WARMER WATERS THAT ARE ALSO PUSHED CLOSER TO SHORE BY
THESE SOUTHERLY TO SOUTHEASTERLY WINDS...SO CONFIDENCE IS NOT HIGH
IN SEA FOG FORMATION AT THE MOMENT BUT WILL CONTINUE TO MONITOR
TRENDS.
AS THE AFOREMENTIONED SURFACE LOW EJECTS ACROSS THE CENTRAL PLAINS
SATURDAY...AN ATTENDANT COLD FRONT WILL PUSH INTO SOUTHEAST TEXAS
SATURDAY AFTERNOON AND REACH THE COAST SATURDAY NIGHT. ISOLATED
THUNDERSTORMS ASSOCIATED WITH THIS COLD FRONT WILL BE POSSIBLE OVER
THE BAYS AND COASTAL WATERS SATURDAY AND SUNDAY. ELEVATED OFFSHORE
WINDS BEHIND THE FRONT MAY WARRANT CAUTION FLAGS SUNDAY. A RETURN TO
ONSHORE FLOW AT THE BEGINNING OF NEXT WEEK WILL BE SHORT-
LIVED...WITH THE NEXT FRONTAL SYSTEM MOVING ACROSS THE COASTAL
WATERS BY MID-WEEK.
HUFFMAN
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 52 70 60 64 42 / 10 30 40 60 30
HOUSTON (IAH) 52 72 63 72 47 / 10 30 50 70 50
GALVESTON (GLS) 59 70 64 70 53 / 10 30 40 70 60
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 6 AM CST FRIDAY FOR
THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS
FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...
WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL 6 AM CST FRIDAY FOR THE FOLLOWING
ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL
20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO
60 NM.
&&
$$
DISCUSSION...23
YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
945 PM CST THU DEC 25 2014
.UPDATE...
SURFACE WINDS ARE BRIEFLY GUSTING TO 20-25 MPH AT TIMES AS 30-35
KNOT SW WINDS AROUND 500 FT OCCASIONALLY MIX DOWN. THESE WINDS
WILL EASE AS BAGGY GRADIENT AROUND WEAK SURFACE LOW REACHES THE
AREA EARLY FRIDAY MORNING. LATEST NAM KEEPING CWA DRY THROUGH 00Z
SATURDAY...WITH THE 00Z GFS BRINGING SOME LIGHT QPF TO NRN SECTIONS
BETWEEN 18Z FRI AND 00Z SAT. SOUNDINGS STILL INDICATE MOSTLY
DRIZZLE OR VERY LIGHT RAIN WITH ANY PRECIP THAT FALLS WITH THIS
FIRST SURFACE WAVE.
BETTER CHANCE OF PRECIP WITH SECOND WAVE FRIDAY NIGHT AND
SATURDAY. A MIX OF RAIN AND SNOW...AND POSSIBLY SOME FREEZING
RAIN UNTIL DENDRITE GROWTH ZONE SATURATES IN THE FAR NW....WITH
MOSTLY RAIN ELSEWHERE INTO SATURDAY AFTERNOON.
&&
.AVIATION/06Z TAFS/...
EXPECT VFR CONDITIONS...WITH SOME OCCASIONAL WIND GUSTS TO 20
KNOTS THROUGH THE OVERNIGHT. WILL HAVE TO WATCH FOR POTENTIAL OF
LOW-LEVEL WIND SHEAR FOR A TIME OVERNIGHT. WINDS EASE IN THE
EARLY TO MID MORNING AS GRADIENT GETS BAGGY WITH APPROACH AND
PASSAGE OF WEAK LOW...WITH MODELS SATURATING THE LOWER LEVELS FROM
WEST TO EAST LATER FRIDAY MORNING INTO THE AFTERNOON. EXPECT MVFR
CIGS TO RETURN. MODELS HINT AT CIGS RISING TO VFR FOR A TIME IN
THE LATE AFTERNOON AND EARLY EVENING BETWEEN THE DEPARTING WEAK
LOW TO THE NORTH AND AHEAD OF NEXT LOW APPROACHING FROM THE
SW...BUT HAVE CIGS GOING BACK DOWN TO BETWEEN 1500 AND 2000 FT BY
EARLY IN THE EVENING AT KMSN AND BY 03Z AT EASTERN TAF SITES.
&&
.MARINE...
ISSUED A SMALL CRAFT ADVISORY UNTIL 9 AM FRIDAY...MAINLY FOR
FREQUENT WIND SWLY GUSTS TO 25 KNOTS...THOUGH WAVES MAY REACH
CRITERIA BETWEEN PORT WASHINGTON AND SHEBOYGAN FOR A TIME
OVERNIGHT. RAP SOUNDINGS HAVE BEEN SHOWING 30-35 KNOT WINDS WITHIN
500 FT LASTING THROUGH MOST OF THE OVERNIGHT...WITH THE CURRENT
VAD WINDS ON THE MKX 88-D RADAR SHOWING 40 KNOTS DOWN TO 2000 FT.
LAKE SHORE OBS HAVE BEEN GUSTING TO 20 KNOTS BUT WITH SLIGHTLY
BETTER MIXING OVER THE WATERS EXPECT GUSTS TO REACH 25 KTS.
CHICAGO CRIB HAS BEEN GUSTING UP TO 28 KNOTS. WINDS NOT EXPECTED
TO BE STRONG FOR AS LONG NORTH OF PORT WASHINGTON...BUT INITIAL
SSW WIND DIRECTION WILL BUILD WAVES OF 3 TO 5 FEET...WITH THE
HIGHER WAVES TOWARD THE OPEN WATER.
WINDS WILL EASE TOWARD 12Z AS GRADIENT BECOMES BAGGY WITH APPROACH
AND PASSAGE OF WEAK SURFACE LOW.
&&
.PREV DISCUSSION... /ISSUED 334 PM CST THU DEC 25 2014/
TONIGHT AND FRIDAY...FORECAST CONFIDENCE IS HIGH.
EXPECTING MAINLY MID AND HIGH LEVEL CLOUDS TONIGHT UNDER SOME
WARM ADVECTION ALOFT. BETWEEN THE WARM ADVECTION...CLOUDS...AND
SOUTHERLY WINDS...SHOULD SEE LOW TEMPS IN THE LOW TO MID 30S.
THESE LOWS WILL BE A FEW DEGREES HIGHER THAN AVERAGE HIGHS FOR
THIS TIME OF YEAR.
MILD SOUTHERLY FLOW LOW LEVEL FLOW WILL CONTINUE FRIDAY. MODELS
SUGGEST THE LOW LEVELS WILL SATURATE WEST TO EAST FROM LATER IN
THE MORNING THROUGH THE AFTERNOON. THUS EXPECTING LOW CLOUDS TO
RETURN TO THE AREA. BETWEEN THE MILD SOUTHERLY FLOW AND MAYBE AT
LEAST MORNING BREAKS IN THE CLOUDS...LOOKS LIKE HIGHS MAY BE EVEN
A COUPLE DEGREES MILDER THAN TODAY.
FRIDAY NIGHT THROUGH SUNDAY...FORECAST CONFIDENCE IS MEDIUM.
MODELS ARE IN DECENT AGREEMENT WITH BRINGING SURFACE LOW NORTHEAST
FROM THE SOUTHERN PLAINS INTO AND THROUGH SOUTHERN WISCONSIN
FRIDAY NIGHT AND SATURDAY. THE NAM/GFS ARE QUICKER WITH THE LOW
TRACK THAN THE ECMWF/CANADIAN MODELS. ALL OF THE MODELS BRING A
SHOT OF WARM AIR ADVECTION AROUND 12Z SATURDAY...FOLLOWED BY THE
PASSAGE OF THE 850 MB TROUGH AT 18Z SATURDAY...THEN THE 500 MB
VORTICITY MAXIMUM SATURDAY AFTERNOON.
NAM/GFS BRING AREA OF LOW LEVEL FRONTOGENESIS RESPONSE THROUGH
THE AREA SATURDAY MORNING...WITH THE MID LEVEL FRONTOGENESIS
CLIPPING AND REMAINING MOSTLY JUST TO THE NORTHWEST OF THE AREA.
THIS IS THE BEST TIME PERIOD FOR UPWARD VERTICAL MOTION WITHIN A
SATURATED AIR COLUMN...PER AREA FORECAST SOUNDINGS.
THE NAM IS SOMEWHAT MILDER THAN THE GFS WITH TEMPERATURE
PROFILES...AND KEEPS MOST OF THE AREA ALL RAIN. THE GFS DOES COOL
THINGS DOWN ENOUGH FOR A MIX AND CHANGE TO LIGHT SNOW IN THE
NORTHWEST PORTIONS OF THE AREA SATURDAY MORNING. BLENDED THESE
SOLUTIONS WITH THE ECMWF AND CANADIAN...WHICH GIVE THIS MIX AND
CHANGE TO LIGHT SNOW IN THE NORTHWEST COUNTIES SATURDAY MORNING.
WENT WITH LIKELY POPS LATER FRIDAY NIGHT IN THE WEST...THEN ACROSS
ALL OF THE AREA SATURDAY MORNING. MIX IN THE NORTHWEST COUNTIES
LATER FRIDAY NIGHT SHOULD BECOME MAINLY LIGHT SNOW SATURDAY
MORNING...WITH ACCUMULATIONS OF UP TO AN INCH. THE REST OF THE
AREA SHOULD BE MILD ENOUGH FOR JUST RAIN OR A LIGHT MIX BEFORE
ENDING.
COLD AIR ADVECTION LATER SATURDAY INTO SATURDAY NIGHT WILL BRING
DRIER AIR INTO THE AREA. THE DRY CONDITIONS WILL LINGER INTO
SUNDAY. TEMPERATURES SHOULD BE MORE SEASONABLE FOR THIS TIME OF
YEAR ON SUNDAY.
SUNDAY NIGHT THROUGH THURSDAY...FORECAST CONFIDENCE IS MEDIUM.
THE GFS AND ECMWF ARE SHOWING THAT THE OVERALL 500 MB PATTERN MAY
SHIFT TO A MORE NORTHWESTERLY FLOW REGIME BY THE MIDDLE OF NEXT
WEEK. THIS SHOULD SIGNAL A TREND TOWARDS COLDER TEMPERATURES
DURING THIS PERIOD.
A PASSING 500 MB VORTICITY MAXIMUM AND SURFACE COLD FRONT MONDAY
INTO MONDAY NIGHT MAY BRING LIGHT SNOW...SO LEFT LOW POPS GOING
FOR NOW. ANOTHER SYSTEM ON NEW YEARS DAY MAY BRING SOME LIGHT
SNOW...AND LEFT POPS GOING THERE. CONSENSUS MODEL TEMPERATURES DO
TREND TO NEAR TO SLIGHTLY BELOW NORMAL BY THE MIDDLE OF THE WEEK.
AVIATION/00Z TAFS/...
VFR CONDITIONS HAVE FINALLY RETURNED TO SOUTHERN WISCONSIN. THINK
THE NAM BRINGS LOW CLOUDS BACK TOO QUICKLY TONIGHT...SO EXPECTING
VFR TO PERSIST THROUGH THE NIGHT.
MOST MODELS DO SHOW THE LOW LEVELS SATURATING WEST TO EAST FROM
LATER FRIDAY MORNING THROUGH THE AFTERNOON. THUS EXPECTING LOW
CLOUDS TO EVENTUALLY RETURN TO THE AREA.
MARINE...
WINDS CONTINUE TO SLOWLY EASE THIS AFTERNOON...WITH LIGHTER WINDS
EXPECTED TONIGHT INTO FRIDAY.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 9 AM CST FRIDAY FOR LMZ643>646.
&&
$$
UPDATE...REM
TONIGHT/FRIDAY AND AVIATION/MARINE...DDV
FRIDAY NIGHT THROUGH THURSDAY...WOOD
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1138 AM CST WED DEC 24 2014
.UPDATE...
ISSUED AT 1005 AM CST WED DEC 24 2014
WATER VAPOR SHOWS A SHORT WAVE TROUGH MOVING NORTH NORTHEAST
THROUGH CENTRAL ILLINOIS. THIS WAVE WILL HELP TO KEEP SOME WEAK
900 TO 800 MB FRONTOGENESIS ACROSS CENTRAL AND NORTH CENTRAL
WISCONSIN AND PARTS OF SOUTHWEST WISCONSIN. SOUNDINGS SHOW THAT
THERE WILL BE SOME ICE CRYSTAL SEEDING FROM ALOFT...SO EXPECT
MAINLY SNOW. LITTLE...IF ANY...ACCUMULATION IS EXPECTED. DUE TO
THIS...INCREASE THE SNOW CHANCES UP INTO THE 20 TO 30 PERCENT
RANGE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 326 AM CST WED DEC 24 2014
THE MAIN FOCUS FOR TODAY IS WITH THE CHANCES FOR SNOW/DRIZZLE.
CURRENTLY...A SHEARED OUT/POSITIVELY TILTED MID LEVEL CLOSED
TROUGH EXTENDS FROM THE UPPER MISSISSIPPI RIVER VALLEY ON DOWN TO
THE WESTERN GULF WITH THE SHEAR AXIS RIGHT OVER WEST CENTRAL
WISCONSIN/EASTERN IOWA. AT THE SURFACE...A LOW/TROUGH IS CENTERED
OVER SOUTHEAST WISCONSIN WITH NORTHWESTERLY FLOW RUNNING ACROSS
THE REGION ON THE BACK SIDE OF THIS SYSTEM. NOT MUCH IN THE WAY OF
COLD AIR BEHIND IT WITH 850MB TEMPERATURES AROUND -5C.
PRECIPITATION-WISE...DRIZZLE HAS DEVELOPED IN A BAND NORTHWEST OF
THE SURFACE LOW AND ALONG THE MID LEVEL SHEAR AXIS ALONG THE
TROUGH. 24.06Z RAP SOUNDINGS FROM ALONG THIS BAND SHOW THAT THERE
IS A LACK OF ICE ALOFT WITH SATURATED LOW LEVELS. THESE SOUNDINGS
SHOW SOME COOLING AROUND 700MB WHICH COULD PUSH THE SATURATED
LAYER DOWN INTO THE -8C RANGE AND PERHAPS CAUSE A CHANGE OVER TO
LIGHT SNOW. WITH FORCING WEAK...EXPECT THAT DRIZZLE WILL BE THE
MAIN PRECIPITATION TYPE WITH IMPACTS MINIMAL THANKS TO SURFACE
TEMPERATURES AT 32 TO 36F. THE 24.06Z HRRR/RAP TAKES THIS MAIN
BAND EASTWARD THROUGH THE MORNING AND DIMINISHING ALONG THE WAY.
AS THE TROUGH/LOW SHIFT OFF TO THE EAST TONIGHT...MID
LEVEL/SURFACE RIDGING WILL PUSH IN FROM THE WEST AND MAY OFFER A
BRIEF PERIOD WHERE SKIES CLEAR OUT LATE TONIGHT. HAVE PLAYED SKY
COVER ON THE PESSIMISTIC SIDE SINCE AS SOON AS THE LOW LEVEL
MOISTURE SHIFTS EAST...SOME HIGH LEVEL CLOUD COVER APPEARS TO MOVE
IN ACCORDING TO THE 24.00Z NAM/GFS. TEMPERATURES WILL NOT DIVE
MUCH TONIGHT WITH LOWS ONLY IN THE MID 20S.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 326 AM CST WED DEC 24 2014
THE FOCUS THEN SHIFTS TO PRECIPITATION CHANCES WITH THE NEXT
SYSTEM TO MOVE IN ON THURSDAY INTO FRIDAY NIGHT. RETURN SOUTHERLY
LOW LEVEL FLOW WILL BRING WARMER AIR UP FROM THE SOUTHERN PLAINS.
THERE HAS BEEN A FAIRLY CONSISTENT MESSAGE FROM THE 24.00Z AND
PREVIOUS MODELS RUNS THAT SHOW A 900-800MB FRONTOGENETIC BAND
DEVELOPING THURSDAY AFTERNOON ACROSS CENTRAL MINNESOTA INTO
NORTHERN WISCONSIN. LOCALLY...24.00Z NAM/GFS ARE SHOWING SOME LOW
LEVEL SATURATION WITH THE WARM AIR ADVECTION TAKING PLACE THURSDAY
NIGHT. IF FORCING WAS A BIT STRONGER IN THE LOW LEVELS...THERE
WOULD BE THE POTENTIAL TO GET SOME DRIZZLE TO FORM BUT AT THE
MOMENT IT LOOKS TOO WEAK.
BROAD MID LEVEL TROUGHING WILL MOVE INTO THE REGION FRIDAY/FRIDAY
NIGHT AND BRING THE NEXT BEST CHANCE FOR SOME SNOW AS IT COMES
THROUGH. AS THE DEEPER LIFT COMES IN WITH A MID LEVEL SHORT WAVE
TROUGH TRACKING THROUGH IOWA...SNOW SHOULD DEVELOP IN A SOUTHWEST
TO NORTHEAST BAND. WITH QPF AMOUNTS AROUND A TENTH OF AN INCH OR
LESS...EXPECT THAT ANY ACCUMULATIONS WILL BE MINOR AT AN INCH OR
LESS.
THE PASSING OF THIS TROUGH WILL MARK A PERIOD OF COLDER AIR
ADVANCING INTO THE REGION FROM CANADA. A VERY CONSISTENT SIGNAL IN
THE 24.00Z GFS/ECMWF IS WITH ANOTHER WAVE OF COLDER AIR MOVING
DOWN FROM NORTHERN CANADA FOR THE MIDDLE PART OF NEXT WEEK WITH
850MB TEMPERATURES FORECAST TO DROP TO -20C OR LOWER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1138 AM CST WED DEC 24 2014
AT TAF TIME...A SNOW SHOWER WAS REDUCING VISIBILITIES TO 1 3/4
MILES AT KRST. LOOKING AT THE RADAR...THIS SNOW SHOWER WILL MOVE
QUICKLY SOUTH OF TAF SITE AND NOT EXPECTING ANY ADDITIONAL ONES
SO DID NOT INCLUDE IT IN THE FORECAST. SOUNDINGS CONTINUE TO
SUGGEST THAT KRST CEILINGS WILL REMAIN IFR THROUGH 25.09Z AND
THEN BECOME MVFR. MEANWHILE KLSE WILL CONTINUE TO SEE MVFR
CEILINGS.
AS FAR AS CLOUD COVER ON CHRISTMAS MORNING...THE LAMP GUIDANCE
SUGGESTS THAT CEILINGS WILL BECOME VFR AFTER 25.11Z AT KRST AND
25.13Z AT KLSE. HOWEVER SOUNDINGS CONTINUE TO SHOW LOW LEVEL
MOISTURE TRAPPED BELOW THE SUBSIDENCE INVERSION. FOR NOW...JUST
STAYED PESSIMISTIC.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...BOYNE
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1005 AM CST WED DEC 24 2014
.UPDATE...THIS AFTERNOON
ISSUED AT 1005 AM CST WED DEC 24 2014
WATER VAPOR SHOWS A SHORT WAVE TROUGH MOVING NORTH NORTHEAST
THROUGH CENTRAL ILLINOIS. THIS WAVE WILL HELP TO KEEP SOME WEAK
900 TO 800 MB FRONTOGENESIS ACROSS CENTRAL AND NORTH CENTRAL
WISCONSIN AND PARTS OF SOUTHWEST WISCONSIN. SOUNDINGS SHOW THAT
THERE WILL BE SOME ICE CRYSTAL SEEDING FROM ALOFT...SO EXPECT
MAINLY SNOW. LITTLE...IF ANY...ACCUMULATION IS EXPECTED. DUE TO
THIS...INCREASE THE SNOW CHANCES UP INTO THE 20 TO 30 PERCENT
RANGE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 326 AM CST WED DEC 24 2014
THE MAIN FOCUS FOR TODAY IS WITH THE CHANCES FOR SNOW/DRIZZLE.
CURRENTLY...A SHEARED OUT/POSITIVELY TILTED MID LEVEL CLOSED
TROUGH EXTENDS FROM THE UPPER MISSISSIPPI RIVER VALLEY ON DOWN TO
THE WESTERN GULF WITH THE SHEAR AXIS RIGHT OVER WEST CENTRAL
WISCONSIN/EASTERN IOWA. AT THE SURFACE...A LOW/TROUGH IS CENTERED
OVER SOUTHEAST WISCONSIN WITH NORTHWESTERLY FLOW RUNNING ACROSS
THE REGION ON THE BACK SIDE OF THIS SYSTEM. NOT MUCH IN THE WAY OF
COLD AIR BEHIND IT WITH 850MB TEMPERATURES AROUND -5C.
PRECIPITATION-WISE...DRIZZLE HAS DEVELOPED IN A BAND NORTHWEST OF
THE SURFACE LOW AND ALONG THE MID LEVEL SHEAR AXIS ALONG THE
TROUGH. 24.06Z RAP SOUNDINGS FROM ALONG THIS BAND SHOW THAT THERE
IS A LACK OF ICE ALOFT WITH SATURATED LOW LEVELS. THESE SOUNDINGS
SHOW SOME COOLING AROUND 700MB WHICH COULD PUSH THE SATURATED
LAYER DOWN INTO THE -8C RANGE AND PERHAPS CAUSE A CHANGE OVER TO
LIGHT SNOW. WITH FORCING WEAK...EXPECT THAT DRIZZLE WILL BE THE
MAIN PRECIPITATION TYPE WITH IMPACTS MINIMAL THANKS TO SURFACE
TEMPERATURES AT 32 TO 36F. THE 24.06Z HRRR/RAP TAKES THIS MAIN
BAND EASTWARD THROUGH THE MORNING AND DIMINISHING ALONG THE WAY.
AS THE TROUGH/LOW SHIFT OFF TO THE EAST TONIGHT...MID
LEVEL/SURFACE RIDGING WILL PUSH IN FROM THE WEST AND MAY OFFER A
BRIEF PERIOD WHERE SKIES CLEAR OUT LATE TONIGHT. HAVE PLAYED SKY
COVER ON THE PESSIMISTIC SIDE SINCE AS SOON AS THE LOW LEVEL
MOISTURE SHIFTS EAST...SOME HIGH LEVEL CLOUD COVER APPEARS TO MOVE
IN ACCORDING TO THE 24.00Z NAM/GFS. TEMPERATURES WILL NOT DIVE
MUCH TONIGHT WITH LOWS ONLY IN THE MID 20S.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 326 AM CST WED DEC 24 2014
THE FOCUS THEN SHIFTS TO PRECIPITATION CHANCES WITH THE NEXT
SYSTEM TO MOVE IN ON THURSDAY INTO FRIDAY NIGHT. RETURN SOUTHERLY
LOW LEVEL FLOW WILL BRING WARMER AIR UP FROM THE SOUTHERN PLAINS.
THERE HAS BEEN A FAIRLY CONSISTENT MESSAGE FROM THE 24.00Z AND
PREVIOUS MODELS RUNS THAT SHOW A 900-800MB FRONTOGENETIC BAND
DEVELOPING THURSDAY AFTERNOON ACROSS CENTRAL MINNESOTA INTO
NORTHERN WISCONSIN. LOCALLY...24.00Z NAM/GFS ARE SHOWING SOME LOW
LEVEL SATURATION WITH THE WARM AIR ADVECTION TAKING PLACE THURSDAY
NIGHT. IF FORCING WAS A BIT STRONGER IN THE LOW LEVELS...THERE
WOULD BE THE POTENTIAL TO GET SOME DRIZZLE TO FORM BUT AT THE
MOMENT IT LOOKS TOO WEAK.
BROAD MID LEVEL TROUGHING WILL MOVE INTO THE REGION FRIDAY/FRIDAY
NIGHT AND BRING THE NEXT BEST CHANCE FOR SOME SNOW AS IT COMES
THROUGH. AS THE DEEPER LIFT COMES IN WITH A MID LEVEL SHORT WAVE
TROUGH TRACKING THROUGH IOWA...SNOW SHOULD DEVELOP IN A SOUTHWEST
TO NORTHEAST BAND. WITH QPF AMOUNTS AROUND A TENTH OF AN INCH OR
LESS...EXPECT THAT ANY ACCUMULATIONS WILL BE MINOR AT AN INCH OR
LESS.
THE PASSING OF THIS TROUGH WILL MARK A PERIOD OF COLDER AIR
ADVANCING INTO THE REGION FROM CANADA. A VERY CONSISTENT SIGNAL IN
THE 24.00Z GFS/ECMWF IS WITH ANOTHER WAVE OF COLDER AIR MOVING
DOWN FROM NORTHERN CANADA FOR THE MIDDLE PART OF NEXT WEEK WITH
850MB TEMPERATURES FORECAST TO DROP TO -20C OR LOWER.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 535 AM CST WED DEC 24 2014
A LINGERING TROUGH OF LOW PRESSURE IS PRODUCING AREAS OF -SN/-DZ
THIS MORNING. LOOKING FOR THIS TO END AT KRST AROUND 16Z AND AROUND
18Z FOR KLSE. OTHERWISE...IFR CIGS TO CONTINUE AT KRST THROUGH THE
PERIOD WITH KLSE EXPECTED TO BE ON THE BORDERLINE OF MVFR/IFR.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...BOYNE
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...DAS
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1002 AM CST WED DEC 24 2014
.UPDATE...
LATEST NAM AND HRRR CONTINUE TO SHOW LESS PRECIP FOR SOUTHERN
WISCONSIN TODAY. WITH SATURATION STRUGGLING UP TO AROUND
-10C...ANY PRECIP THAT DOES MOVE THROUGH WILL PROBABLY BE EITHER
LIGHT SNOW OR LIGHT RAIN. SEEING THIS MIX RIGHT NOW TO THE WEST.
AT THIS POINT...NO APPRECIABLE RAIN OR SNOW IS EXPECTED AS
DEEPENING LOW PRESSURE LIFTS NORTH WELL TO THE EAST OF THE
FORECAST AREA. WILL PROBABLY NEED TO CUT BACK ON POPS FOR THE
REMAINDER OF THE DAY. LIGHT PRECIP WILL WIND DOWN BY THE LATE
EVENING HOURS.
VISIBILITIES CONTINUE TO IMPROVE ACROSS THE FORECAST AREA THIS
MORNING...SO WILL ALLOW THE DENSE FOG ADVISORY TO EXPIRE AT 10 AM.
&&
.AVIATION/18Z TAFS/...
LATEST MODELS CONTINUE TO THE DOWNWARD TREND IN PRECIP
CHANCES...WITH NO APPRECIABLE RAIN OR SNOW EXPECTED THROUGH THE
REMAINDER OF THE DAY. STILL MAY SEE A LITTLE LIGHT SNOW OR RAIN AT
TIMES INTO THE EVENING HOURS AS THE UPPER THROUGH SWINGS THROUGH.
VISIBILITIES WILL CONTINUE TO IMPROVE THROUGH LATE
MORNING...THOUGH LOW CLOUDS WILL LIKELY PERSIST INTO TONIGHT.
SHOULD SEE A RETURN TO VFR CONDITIONS BY MID OR LATE THURSDAY
MORNING.
&&
.MARINE...
WILL FURTHER DELAY START OF SMALL CRAFT ADVISORY UNTIL 00Z.
FARTHER EAST TRACK OF LOW PRESSURE MOVING NORTHEAST TOWARD
THE CENTRAL GREAT LAKES DELAYING TIGHTENING PRESSURE GRADIENT OVER
LAKE MICHIGAN. HENCE NOT EXPECTING GUSTY NORTHWEST WINDS TO DEVELOP
UNTIL TONIGHT. SHIP REPORT EAST OF RACINE AT EDGE OF NEARSHORE
WATERS HAD SUSTAINED WINDS OF 12 KT.
&&
.PREV DISCUSSION... /ISSUED 342 AM CST WED DEC 24 2014/
SHORT TERM...
THE 00Z NAM/GFS AND ECMWF HAVE TRENDED EAST WITH LOW EXPECTED TO
TRACK ALONG IN/OH BORDER AND INTO SOUTHEAST MICHIGAN. RAPID
DEEPENING PHASE OF ABOUT 1 MB/HOUR EXPECTED TO START IN THE
MORNING IN OHIO VALLEY AND CONTINUES INTO THE EVENING AS STORM
CROSSES SOUTHEAST MICHIGAN AND BOUND FOR GEORGIAN BAY.
WILL CONTINUE THE PREVIOUS IDEA OF LOWERING THE ACCUMULATING SNOW
AND HAVE CANCELLED THE WINTER WEATHER ADVISORIES. NAM FORECAST
SOUNDINGS SHOW A FAIRLY DRY LAYER FROM 4 TO 13 THSD FT EARLY THIS
MORNING OVER THE FAR SOUTHEAST. THIS DIMINISHES...BUT DEEP
SATURATION IS RATHER BRIEF LATE THIS MORNING AND EARLY AFTERNOON
BEFORE DRYING OCCURS AROUND 10 THSD FT EARLY THIS EVENING. SNOW
RATIOS ARE RATHER LOW IN THE FAR EAST WHERE THE PRECIPITATION WOULD
BE MORE. THE 12Z ECMWF HAS LITTLE IF ANY MEASURABLE PRECIPITATION
OVER SOUTHEAST WISCONSIN. THE HRRR IS THE MOST AGGRESSIVE MESO MODEL
WITH AROUND 0.15 OF PRECIPITATION OVER THE LAKESHORE COUNTIES.
HOWEVER EVEN THIS WOULD BE LIMITED DUE TO THE CONSENSUS 6 TO 1 SNOW
RATIOS.
THE NEW 06Z NAM CONTIUES THE EASTWARD TREND AND NOW AGREES WITH THE
ECMWF WITH LITTLE IN THE WAY OF MEASURABLE PRECIPITATION OVER
EASTERN WISCONSIN.
CHRISTMAS DAY...FORECAST CONFIDENCE HIGH.
HIGH PRESSURE CENTERED OVER THE GULF COASTAL STATES WILL STRETCH ITS
AXIS UP INTO THE GREAT LAKES FOR CHRISTMAS...BRINGING A DRY AND
RATHER PLEASANT DAY WITH HIGHS IN THE MID TO UPPER 30S. WE MIGHT
EVEN SEE A LITTLE SUNSHINE.
LONG TERM...
FRIDAY THROUGH SATURDAY... FORECAST CONFIDENCE MEDIUM.
FRIDAY WEATHER WILL REMAIN QUIET AND MILD OVER SOUTHERN WI. HIGHS
ARE EXPECTED IN THE LOWER 40S WITH A SOUTHERLY BREEZE. THERE WILL
LIKELY BE LOW CLOUDS AROUND DUE TO THE LOW LEVEL MOISTURE SPREADING
BACK INTO THE REGION.
A WEAK SURFACE LOW PRESSURE TROUGH AND COLD FRONT WILL SLIDE THROUGH
SOUTHERN WI FRIDAY NIGHT. MEANWHILE... A 500MB SHORTWAVE WITHIN THE
LEFT EXIT REGION OF A STRENGTHENING UPPER JET WILL BE TRACKING
THROUGH CENTRAL AND NORTHERN WI. MODELS ARE SHOWING TWO AREAS OF
PRECIP ASSOCIATED WITH THIS SYSTEM... ONE MAINLY IN IL THAT CLIPS
SOUTHEAST WI AND THE OTHER OVER THE NORTHWEST HALF OF WI. THE MKX
FORECAST AREA WILL LAND BETWEEN THESE TWO FAVORED AREAS. THE GFS AND
NOW THE 06Z NAM SHOW THESE TWO AREAS CLEARLY IN THE QPF FIELD AND
THE ECMWF DOES TO A LESSER EXTENT.
TEMPERATURE PROFILES SHOW THAT MOST OF THE PRECIP IN SOUTHEAST WI
WILL FALL AS RAIN AND THEN GRADUALLY CHANGE OVER TO SNOW OVERNIGHT
INTO SATURDAY MORNING BEFORE ENDING. IN THE NORTHERN FORECAST
AREA... THE TEMP PROFILE IS COLDER AND WE ARE LOOKING AT A RAIN/SNOW
MIX CHANGING OVER TO SNOW BY MIDNIGHT. PRECIP AMOUNTS WILL BE
LIGHT... LESS THAN A TENTH OF AN INCH. ANY SNOW ACCUMULATION WOULD
BE LESS THAN A HALF INCH.
THE ECWMF HANGS ONTO THE LIGHT PRECIP LONGER IN SOUTHEAST WI THAN
THE GFS ON SATURDAY. COLD AIR ADVECTION AND CLOUDS WILL LEAD TO
STEADY TEMPS AROUND 30 THROUGH THE DAY.
SUNDAY THROUGH TUESDAY... FORECAST CONFIDENCE HIGH.
SURFACE HIGH PRESSURE AND DRY WEATHER WILL DOMINATE FOR SUNDAY AND
MONDAY... BUT TEMPERATURES WILL BE BELOW AVERAGE.
ANOTHER BROAD TROUGH WILL CROSS THE COUNTRY EARLY NEXT WEEK AND MAY
BRING SOME LIGHT SNOW ACROSS WISCONSIN ON A SHORTWAVE MONDAY NIGHT
INTO TUESDAY.
THEN A DEEPER UPPER LEVEL TROUGH IS FORECAST TO DROP DOWN FROM
CANADA THROUGH THE UPPER MIDWEST AND BRING JANUARY-LIKE TEMPERATURES
INTO THE REGION FOR THE NEW YEAR.
AVIATION/12Z TAFS/...
EXPECT IFR/LIFR CIGS OVER MUCH OF SOUTH CENTRAL AND PORTIONS OF
SOUTHEAST WISCONSIN. LIFR FOG EXPECTED TO PERSIST FOR A FEW HOURS
AFTER SUNRISE OVER PORTIONS OF SOUTH CENTRAL WISCONSIN.
OVER THE FAR SOUTHEAST IFR CIGS POSSIBLE LATER THIS MORNING AND
AFTERNOON. DUE TO THE EXPECTED MIX OF RAIN AND SNOW FAR EAST
TEMPERATURES IN THE MID TO UPPER 30S AT SURFACE MAY PREVENT
SIGNIFICANT CHANGEOVER AND PAVEMENT MAY REMAIN MAINLY WET THROUGH
THE PRECIPITATION DURATION. HOWEVER STILL SOME ACCUMULATIONS ARE
POSSIBLE.
MARINE...
RAPID DEEPENING LOW WILL RESULT IN BRISK NORTH AND THEN NORTHWEST
WINDS THIS AFTERNOON INTO EARLY THURSDAY. WITH THE LOW GOING FURTHER
EAST THE THREAT OF GALES IS DIMINISHING ON THE WEST SIDE OF LAKE
MICHIGAN SO CURRENT SMALL CRAFT ADVISORY SHOULD SUFFICE.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO NOON CST THURSDAY
FOR LMZ643>646
&&
$$
UPDATE...DDV/MBK
TODAY/TONIGHT AND AVIATION/MARINE...HENTZ
THURSDAY THROUGH TUESDAY...MRC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
535 AM CST WED DEC 24 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 326 AM CST WED DEC 24 2014
THE MAIN FOCUS FOR TODAY IS WITH THE CHANCES FOR SNOW/DRIZZLE.
CURRENTLY...A SHEARED OUT/POSITIVELY TILTED MID LEVEL CLOSED
TROUGH EXTENDS FROM THE UPPER MISSISSIPPI RIVER VALLEY ON DOWN TO
THE WESTERN GULF WITH THE SHEAR AXIS RIGHT OVER WEST CENTRAL
WISCONSIN/EASTERN IOWA. AT THE SURFACE...A LOW/TROUGH IS CENTERED
OVER SOUTHEAST WISCONSIN WITH NORTHWESTERLY FLOW RUNNING ACROSS
THE REGION ON THE BACK SIDE OF THIS SYSTEM. NOT MUCH IN THE WAY OF
COLD AIR BEHIND IT WITH 850MB TEMPERATURES AROUND -5C.
PRECIPITATION-WISE...DRIZZLE HAS DEVELOPED IN A BAND NORTHWEST OF
THE SURFACE LOW AND ALONG THE MID LEVEL SHEAR AXIS ALONG THE
TROUGH. 24.06Z RAP SOUNDINGS FROM ALONG THIS BAND SHOW THAT THERE
IS A LACK OF ICE ALOFT WITH SATURATED LOW LEVELS. THESE SOUNDINGS
SHOW SOME COOLING AROUND 700MB WHICH COULD PUSH THE SATURATED
LAYER DOWN INTO THE -8C RANGE AND PERHAPS CAUSE A CHANGE OVER TO
LIGHT SNOW. WITH FORCING WEAK...EXPECT THAT DRIZZLE WILL BE THE
MAIN PRECIPITATION TYPE WITH IMPACTS MINIMAL THANKS TO SURFACE
TEMPERATURES AT 32 TO 36F. THE 24.06Z HRRR/RAP TAKES THIS MAIN
BAND EASTWARD THROUGH THE MORNING AND DIMINISHING ALONG THE WAY.
AS THE TROUGH/LOW SHIFT OFF TO THE EAST TONIGHT...MID
LEVEL/SURFACE RIDGING WILL PUSH IN FROM THE WEST AND MAY OFFER A
BRIEF PERIOD WHERE SKIES CLEAR OUT LATE TONIGHT. HAVE PLAYED SKY
COVER ON THE PESSIMISTIC SIDE SINCE AS SOON AS THE LOW LEVEL
MOISTURE SHIFTS EAST...SOME HIGH LEVEL CLOUD COVER APPEARS TO MOVE
IN ACCORDING TO THE 24.00Z NAM/GFS. TEMPERATURES WILL NOT DIVE
MUCH TONIGHT WITH LOWS ONLY IN THE MID 20S.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 326 AM CST WED DEC 24 2014
THE FOCUS THEN SHIFTS TO PRECIPITATION CHANCES WITH THE NEXT
SYSTEM TO MOVE IN ON THURSDAY INTO FRIDAY NIGHT. RETURN SOUTHERLY
LOW LEVEL FLOW WILL BRING WARMER AIR UP FROM THE SOUTHERN PLAINS.
THERE HAS BEEN A FAIRLY CONSISTENT MESSAGE FROM THE 24.00Z AND
PREVIOUS MODELS RUNS THAT SHOW A 900-800MB FRONTOGENETIC BAND
DEVELOPING THURSDAY AFTERNOON ACROSS CENTRAL MINNESOTA INTO
NORTHERN WISCONSIN. LOCALLY...24.00Z NAM/GFS ARE SHOWING SOME LOW
LEVEL SATURATION WITH THE WARM AIR ADVECTION TAKING PLACE THURSDAY
NIGHT. IF FORCING WAS A BIT STRONGER IN THE LOW LEVELS...THERE
WOULD BE THE POTENTIAL TO GET SOME DRIZZLE TO FORM BUT AT THE
MOMENT IT LOOKS TOO WEAK.
BROAD MID LEVEL TROUGHING WILL MOVE INTO THE REGION FRIDAY/FRIDAY
NIGHT AND BRING THE NEXT BEST CHANCE FOR SOME SNOW AS IT COMES
THROUGH. AS THE DEEPER LIFT COMES IN WITH A MID LEVEL SHORT WAVE
TROUGH TRACKING THROUGH IOWA...SNOW SHOULD DEVELOP IN A SOUTHWEST
TO NORTHEAST BAND. WITH QPF AMOUNTS AROUND A TENTH OF AN INCH OR
LESS...EXPECT THAT ANY ACCUMULATIONS WILL BE MINOR AT AN INCH OR
LESS.
THE PASSING OF THIS TROUGH WILL MARK A PERIOD OF COLDER AIR
ADVANCING INTO THE REGION FROM CANADA. A VERY CONSISTENT SIGNAL IN
THE 24.00Z GFS/ECMWF IS WITH ANOTHER WAVE OF COLDER AIR MOVING
DOWN FROM NORTHERN CANADA FOR THE MIDDLE PART OF NEXT WEEK WITH
850MB TEMPERATURES FORECAST TO DROP TO -20C OR LOWER.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 535 AM CST WED DEC 24 2014
A LINGERING TROUGH OF LOW PRESSURE IS PRODUCING AREAS OF -SN/-DZ
THIS MORNING. LOOKING FOR THIS TO END AT KRST AROUND 16Z AND AROUND
18Z FOR KLSE. OTHERWISE...IFR CIGS TO CONTINUE AT KRST THROUGH THE
PERIOD WITH KLSE EXPECTED TO BE ON THE BORDERLINE OF MVFR/IFR.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...DAS
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
342 AM CST WED DEC 24 2014
.SHORT TERM...
THE 00Z NAM/GFS AND ECMWF HAVE TRENDED EAST WITH LOW EXPECTED TO
TRACK ALONG IN/OH BORDER AND INTO SOUTHEAST MICHIGAN. RAPID
DEEPENING PHASE OF ABOUT 1 MB/HOUR EXPECTED TO START IN THE
MORNING IN OHIO VALLEY AND CONTINUES INTO THE EVENING AS STORM
CROSSES SOUTHEAST MICHIGAN AND BOUND FOR GEORGIAN BAY.
WILL CONTINUE THE PREVIOUS IDEA OF LOWERING THE ACCUMULATING SNOW
AND HAVE CANCELLED THE WINTER WEATHER ADVISORIES. NAM FORECAST
SOUNDINGS SHOW A FAIRLY DRY LAYER FROM 4 TO 13 THSD FT EARLY THIS
MORNING OVER THE FAR SOUTHEAST. THIS DIMINISHES...BUT DEEP
SATURATION IS RATHER BRIEF LATE THIS MORNING AND EARLY AFTERNOON
BEFORE DRYING OCCURS AROUND 10 THSD FT EARLY THIS EVENING. SNOW
RATIOS ARE RATHER LOW IN THE FAR EAST WHERE THE PRECIPITATION WOULD
BE MORE. THE 12Z ECMWF HAS LITTLE IF ANY MEASURABLE PRECIPITATION
OVER SOUTHEAST WISCONSIN. THE HRRR IS THE MOST AGGRESSIVE MESO MODEL
WITH AROUND 0.15 OF PRECIPITATION OVER THE LAKESHORE COUNTIES.
HOWEVER EVEN THIS WOULD BE LIMITED DUE TO THE CONSENSUS 6 TO 1 SNOW
RATIOS.
THE NEW 06Z NAM CONTIUES THE EASTWARD TREND AND NOW AGREES WITH THE
ECMWF WITH LITTLE IN THE WAY OF MEASURABLE PRECIPITATION OVER
EASTERN WISCONSIN.
CHRISTMAS DAY...FORECAST CONFIDENCE HIGH.
HIGH PRESSURE CENTERED OVER THE GULF COASTAL STATES WILL STRETCH ITS
AXIS UP INTO THE GREAT LAKES FOR CHRISTMAS...BRINGING A DRY AND
RATHER PLEASANT DAY WITH HIGHS IN THE MID TO UPPER 30S. WE MIGHT
EVEN SEE A LITTLE SUNSHINE.
.LONG TERM...
FRIDAY THROUGH SATURDAY... FORECAST CONFIDENCE MEDIUM.
FRIDAY WEATHER WILL REMAIN QUIET AND MILD OVER SOUTHERN WI. HIGHS
ARE EXPECTED IN THE LOWER 40S WITH A SOUTHERLY BREEZE. THERE WILL
LIKELY BE LOW CLOUDS AROUND DUE TO THE LOW LEVEL MOISTURE SPREADING
BACK INTO THE REGION.
A WEAK SURFACE LOW PRESSURE TROUGH AND COLD FRONT WILL SLIDE THROUGH
SOUTHERN WI FRIDAY NIGHT. MEANWHILE... A 500MB SHORTWAVE WITHIN THE
LEFT EXIT REGION OF A STRENGTHENING UPPER JET WILL BE TRACKING
THROUGH CENTRAL AND NORTHERN WI. MODELS ARE SHOWING TWO AREAS OF
PRECIP ASSOCIATED WITH THIS SYSTEM... ONE MAINLY IN IL THAT CLIPS
SOUTHEAST WI AND THE OTHER OVER THE NORTHWEST HALF OF WI. THE MKX
FORECAST AREA WILL LAND BETWEEN THESE TWO FAVORED AREAS. THE GFS AND
NOW THE 06Z NAM SHOW THESE TWO AREAS CLEARLY IN THE QPF FIELD AND
THE ECMWF DOES TO A LESSER EXTENT.
TEMPERATURE PROFILES SHOW THAT MOST OF THE PRECIP IN SOUTHEAST WI
WILL FALL AS RAIN AND THEN GRADUALLY CHANGE OVER TO SNOW OVERNIGHT
INTO SATURDAY MORNING BEFORE ENDING. IN THE NORTHERN FORECAST
AREA... THE TEMP PROFILE IS COLDER AND WE ARE LOOKING AT A RAIN/SNOW
MIX CHANGING OVER TO SNOW BY MIDNIGHT. PRECIP AMOUNTS WILL BE
LIGHT... LESS THAN A TENTH OF AN INCH. ANY SNOW ACCUMULATION WOULD
BE LESS THAN A HALF INCH.
THE ECWMF HANGS ONTO THE LIGHT PRECIP LONGER IN SOUTHEAST WI THAN
THE GFS ON SATURDAY. COLD AIR ADVECTION AND CLOUDS WILL LEAD TO
STEADY TEMPS AROUND 30 THROUGH THE DAY.
SUNDAY THROUGH TUESDAY... FORECAST CONFIDENCE HIGH.
SURFACE HIGH PRESSURE AND DRY WEATHER WILL DOMINATE FOR SUNDAY AND
MONDAY... BUT TEMPERATURES WILL BE BELOW AVERAGE.
ANOTHER BROAD TROUGH WILL CROSS THE COUNTRY EARLY NEXT WEEK AND MAY
BRING SOME LIGHT SNOW ACROSS WISCONSIN ON A SHORTWAVE MONDAY NIGHT
INTO TUESDAY.
THEN A DEEPER UPPER LEVEL TROUGH IS FORECAST TO DROP DOWN FROM
CANADA THROUGH THE UPPER MIDWEST AND BRING JANUARY-LIKE TEMPERATURES
INTO THE REGION FOR THE NEW YEAR.
&&
.AVIATION/12Z TAFS/...
EXPECT IFR/LIFR CIGS OVER MUCH OF SOUTH CENTRAL AND PORTIONS OF
SOUTHEAST WISCONSIN. LIFR FOG EXPECTED TO PERSIST FOR A FEW HOURS
AFTER SUNRISE OVER PORTIONS OF SOUTH CENTRAL WISCONSIN.
OVER THE FAR SOUTHEAST IFR CIGS POSSIBLE LATER THIS MORNING AND
AFTERNOON. DUE TO THE EXPECTED MIX OF RAIN AND SNOW FAR EAST
TEMPERATURES IN THE MID TO UPPER 30S AT SURFACE MAY PREVENT
SIGNIFICANT CHANGEOVER AND PAVEMENT MAY REMAIN MAINLY WET THROUGH
THE PRECIPITATION DURATION. HOWEVER STILL SOME ACCUMULATIONS ARE
POSSIBLE.
&&
.MARINE...
RAPID DEEPENING LOW WILL RESULT IN BRISK NORTH AND THEN NORTHWEST
WINDS THIS AFTERNOON INTO EARLY THURSDAY. WITH THE LOW GOING FURTHER
EAST THE THREAT OF GALES IS DIMINISHING ON THE WEST SIDE OF LAKE
MICHIGAN SO CURRENT SMALL CRAFT ADVISORY SHOULD SUFFICE.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY FROM NOON TODAY TO NOON CST THURSDAY FOR
LMZ643>646.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...HENTZ
THURSDAY THROUGH TUESDAY...MRC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
326 AM CST WED DEC 24 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 326 AM CST WED DEC 24 2014
THE MAIN FOCUS FOR TODAY IS WITH THE CHANCES FOR SNOW/DRIZZLE.
CURRENTLY...A SHEARED OUT/POSITIVELY TILTED MID LEVEL CLOSED
TROUGH EXTENDS FROM THE UPPER MISSISSIPPI RIVER VALLEY ON DOWN TO
THE WESTERN GULF WITH THE SHEAR AXIS RIGHT OVER WEST CENTRAL
WISCONSIN/EASTERN IOWA. AT THE SURFACE...A LOW/TROUGH IS CENTERED
OVER SOUTHEAST WISCONSIN WITH NORTHWESTERLY FLOW RUNNING ACROSS
THE REGION ON THE BACK SIDE OF THIS SYSTEM. NOT MUCH IN THE WAY OF
COLD AIR BEHIND IT WITH 850MB TEMPERATURES AROUND -5C.
PRECIPITATION-WISE...DRIZZLE HAS DEVELOPED IN A BAND NORTHWEST OF
THE SURFACE LOW AND ALONG THE MID LEVEL SHEAR AXIS ALONG THE
TROUGH. 24.06Z RAP SOUNDINGS FROM ALONG THIS BAND SHOW THAT THERE
IS A LACK OF ICE ALOFT WITH SATURATED LOW LEVELS. THESE SOUNDINGS
SHOW SOME COOLING AROUND 700MB WHICH COULD PUSH THE SATURATED
LAYER DOWN INTO THE -8C RANGE AND PERHAPS CAUSE A CHANGE OVER TO
LIGHT SNOW. WITH FORCING WEAK...EXPECT THAT DRIZZLE WILL BE THE
MAIN PRECIPITATION TYPE WITH IMPACTS MINIMAL THANKS TO SURFACE
TEMPERATURES AT 32 TO 36F. THE 24.06Z HRRR/RAP TAKES THIS MAIN
BAND EASTWARD THROUGH THE MORNING AND DIMINISHING ALONG THE WAY.
AS THE TROUGH/LOW SHIFT OFF TO THE EAST TONIGHT...MID
LEVEL/SURFACE RIDGING WILL PUSH IN FROM THE WEST AND MAY OFFER A
BRIEF PERIOD WHERE SKIES CLEAR OUT LATE TONIGHT. HAVE PLAYED SKY
COVER ON THE PESSIMISTIC SIDE SINCE AS SOON AS THE LOW LEVEL
MOISTURE SHIFTS EAST...SOME HIGH LEVEL CLOUD COVER APPEARS TO MOVE
IN ACCORDING TO THE 24.00Z NAM/GFS. TEMPERATURES WILL NOT DIVE
MUCH TONIGHT WITH LOWS ONLY IN THE MID 20S.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 326 AM CST WED DEC 24 2014
THE FOCUS THEN SHIFTS TO PRECIPITATION CHANCES WITH THE NEXT
SYSTEM TO MOVE IN ON THURSDAY INTO FRIDAY NIGHT. RETURN SOUTHERLY
LOW LEVEL FLOW WILL BRING WARMER AIR UP FROM THE SOUTHERN PLAINS.
THERE HAS BEEN A FAIRLY CONSISTENT MESSAGE FROM THE 24.00Z AND
PREVIOUS MODELS RUNS THAT SHOW A 900-800MB FRONTOGENETIC BAND
DEVELOPING THURSDAY AFTERNOON ACROSS CENTRAL MINNESOTA INTO
NORTHERN WISCONSIN. LOCALLY...24.00Z NAM/GFS ARE SHOWING SOME LOW
LEVEL SATURATION WITH THE WARM AIR ADVECTION TAKING PLACE THURSDAY
NIGHT. IF FORCING WAS A BIT STRONGER IN THE LOW LEVELS...THERE
WOULD BE THE POTENTIAL TO GET SOME DRIZZLE TO FORM BUT AT THE
MOMENT IT LOOKS TOO WEAK.
BROAD MID LEVEL TROUGHING WILL MOVE INTO THE REGION FRIDAY/FRIDAY
NIGHT AND BRING THE NEXT BEST CHANCE FOR SOME SNOW AS IT COMES
THROUGH. AS THE DEEPER LIFT COMES IN WITH A MID LEVEL SHORT WAVE
TROUGH TRACKING THROUGH IOWA...SNOW SHOULD DEVELOP IN A SOUTHWEST
TO NORTHEAST BAND. WITH QPF AMOUNTS AROUND A TENTH OF AN INCH OR
LESS...EXPECT THAT ANY ACCUMULATIONS WILL BE MINOR AT AN INCH OR
LESS.
THE PASSING OF THIS TROUGH WILL MARK A PERIOD OF COLDER AIR
ADVANCING INTO THE REGION FROM CANADA. A VERY CONSISTENT SIGNAL IN
THE 24.00Z GFS/ECMWF IS WITH ANOTHER WAVE OF COLDER AIR MOVING
DOWN FROM NORTHERN CANADA FOR THE MIDDLE PART OF NEXT WEEK WITH
850MB TEMPERATURES FORECAST TO DROP TO -20C OR LOWER.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 1100 PM CST TUE DEC 23 2014
EXTENSIVE IFR/MVFR CLOUD SHIELD ACROSS THE REGION...AND DON/T EXPECT
MUCH CHANGE THROUGH WEDNESDAY. NAM RH FIELDS/BUFKIT SOUNDINGS
SUGGEST A BREAK CHRISTMAS NIGHT...BUT IT WOULD BE SHORT LIVED.
WITH THE AMPLE LOW LEVEL MOISTURE HOLDING FAST UNDER THE
INVERSION...COULD HAVE SOME VSBY REDUCTIONS FROM BR AND POTENTIALLY
-DZ. LITTLE EVIDENCE VIA LATEST SFC OBS/RADAR IMAGERY THOUGH. AFTER
12Z...HRRR/NAM12/GFS ALL SUGGEST ENOUGH THERMODYNAMIC/FRONTOGENETIC
LIFT WITH A SFC BOUNDARY TO SPARK AREAS OF LIGHT PCPN FOR WED
MORNING. ITS UNCLEAR IF THERE WILL BE ICE IN THE CLOUD...AS BUFKIT
SOUNDINGS HOVER CLOSE TO -10 C WITH CLOUD TOPS. DEPTH IS GOOD...AND
POTENTIALLY DEEP ENOUGH FOR -RA AS OPPOSED TO -DZ. IF IT WOULD BE
JUST SNOW...A BRIEF DIP TO 2SM WOULD BE POSSIBLE. MOST OF THIS
ACTIVITY SHOULD SHIFT EAST BY 18Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
405 AM CST FRI DEC 26 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 358 AM CST FRI DEC 26 2014
SATELLITE AND THE RUC INDICATE A CLOSED H500 MB LOW MOVING ACROSS
THE FOUR CORNERS. A DEFORMATION BAND OF SNOW EXTENDED FROM NRN
COLO INTO WY WHICH WAS SHOWING SIGNS OF WEAKENING. A NEW
DEFORMATION BAND WAS DEVELOPING ACROSS NRN NM AND THIS DISTURBANCE
IS FCST BY THE MODELS TO LIFT THROUGH THE FCST AREA TODAY AND
TONIGHT AFFECTING AREAS ALONG AND EAST OF A LINE FROM KIML-KOGA-
KTIF-KONL. THE MODEL CONSENSUS SUGGESTS THE BEST SNOWFALL...4 TO 6
INCHES...WOULD LIFT FROM HAYES CENTER TO NORTH PLATTE AND THEN
NORTHEAST THROUGH BURWELL AND ONEILL. ROCK AND HOLT COUNTY HAVE
BEEN ADDED TO THE WINTER WEATHER ADVISORY IN EFFECT UNTIL 06Z
TONIGHT.
THE MODEL QPF IS MOST TIGHTLY CLUSTERED OVER NORTH PLATTE AND MODEL
QPF SPREAD INCREASES EAST AND WEST OF THAT POINT. WE ARE EXPECTING
AROUND 0.25 TO 0.33 INCHES OF QPF FROM THIS DISTURBANCE. THE GFS WAS
THE FIRST MODEL TWO DAYS AGO TO INDICATE A SEMI CLOSED H700MB LOW
LIFTING NORTHEAST THROUGH THE FCST AREA. THE OTHER MODELS CARRIED
THIS DISTURBANCE EAST MOSTLY THROUGH KS AND SCNTL/ERN NEB. NOW ALL
THE MODELS ARE IN AGREEMENT LIFTING THIS LOW THROUGH THE FCST AREA.
THERE IS SOME WOBBLING GOING ON WHICH IS NORMAL. THE RAP IS A BIT
EAST OF THE MODEL CONSENSUS. BUT GIVEN THE PERFORMANCE OF THE MODELS
YESTERDAY FAVORING THE CNTL PANHANDLE VS THE RAP WITH THE CHEYENNE
DIVIDE...THE MODEL CONSENSUS WINS THE FCST. GIVEN THE MODEL
CONSENSUS AND A 15 TO 1 RATIO...4 TO 6 INCHES OF SNOW APPEARS
LIKELY. THE 06Z NAM CONTINUES TO INDICATE THESE AMOUNTS FROM
KIML-KLBF-KBUB-KONL BUT SHOWS 6 TO 8 INCHES FROM KBBW-KBUB-KONL.
THIS IS A TREND IN THE MODELS FOR SLOWER DEVELOPMENT AND THE NAM
ACTUALLY HAS A CLOSED H700MB LOW OVER KGRI AT 03Z THIS EVENING WHILE
THE MODEL CONSENSUS WAS SHOWS THIS LOW AS AN OPEN WAVE. IF THIS
TREND CONTINUES AND A CLOSED H700MB LOW WERE TO TRAVERSE THE FCST
AREA...THE CHANCE OF HEAVY SNOW WOULD INCREASE.
FOR NOW THE FCST IS FOR 3 TO 6 INCHES OF SNOW IN THE ADVISORY AREA.
THIS IS AN INCREASE OF 2 INCHES OVER THE PREVIOUS FORECAST.
PATCHY FREEZING DRIZZLE CONTINUES THIS MORNING ASSOCIATED WITH
TRAPPED MOISTURE BELOW A 700MB DRY INTRUSION. THIS DRIZZLE IS
EXPECTED TO CLEAR THE FCST AREA 12Z-15Z THIS MORNING AND A CHECK OF
THE NEDOR WEBSITE INDICATES ROADS IN CUSTER COUNTY ARE COMPLETELY
COVERED WITH ICE...UNTREATED AND NO TRAVEL IS ADVISED SO THE
ADVISORY WILL BEGIN EARLIER IN THIS AREA. WITH QUICKLY CHANGING
AND DETERIORATING CONDITIONS...WILL ADD ADDITIONAL COUNTIES TO THE
ADVISORY TO THE NORTHEAST AND ISSUE A FREEZING RAIN ADVISORY FOR
FAR NORTH CENTRAL NEBRASKA THROUGH THIS MORNING.
THE MODELS INDICATE DRY AIR WILL WORK EAST TO HIGHWAY 83 AFTER
MIDNIGHT ALLOWING FOR A FEW TO SEVERAL HOURS OF MODEST RADIATIONAL
COOLING. LOWS TONIGHT ALONG AND WEST OF HIGHWAY 83 SHOULD FALL TO
NEAR OR BELOW ZERO IN MANY AREAS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 358 AM CST FRI DEC 26 2014
PRIMARY FORECAST CONCERNS FOR THIS PERIOD DEALS WITH TEMPERATURES
AS A COLDER AIRMASS STAYS IN PLACE ACROSS THE REGION...THEN WITH
AN INTRUDING ARCTIC COLD FRONT EARLY NEXT WEEK WHICH BRINGS AN
AIRMASS INTO THE AREA THAT IS COLDER YET ALONG WITH CHANCES FOR
SNOW.
MODELS ARE IN FAIRLY GOOD AGREEMENT WITH THE EVOLUTION OF THE UPPER
LEVEL PATTERN THROUGH THE NEXT WEEK WHICH LEADS TO SLIGHTLY ABOVE
AVERAGE CONFIDENCE IN THE FORECAST. THAT BEING SAID...THERE ARE
DIFFERENCES IN DETAILS OF INDIVIDUAL SHORTWAVE TROUGHS MOVING ACROSS
THE AREA WHICH DOES PROVIDE SOME UNCERTAINTY FOR PORTIONS OF THE
FORECAST.
BY SATURDAY MORNING THE SHORTWAVE TROUGH THAT WILL PUSH UP THROUGH
KANSAS AND EASTERN NEBRASKA WILL BE ON ITS WAY EAST OF THE REGION
WHILE A WEAK SHORTWAVE COMING OUT OF THE NORTHERN STREAM WILL PASS
ACROSS THE FORECAST AREA THROUGH THE DAY SATURDAY. BEHIND THIS
SHORTWAVE SUBSIDENCE WILL BE INCREASING WHICH SHOULD LEAD TO
CLEARING SKIES THROUGH THE DAY. HIGH PRESSURE AT THE SURFACE WILL
DRIFT TO THE SOUTHEAST THROUGH THE DAY AND SATURDAY NIGHT. SO
LOOKING FOR DECREASING WINDS...BUT AS IT WILL BE CENTERED SOUTH AND
EAST OF THE LOCAL AREA THE PRESSURE GRADIENT MAY KEEP WINDS FROM
GOING CALM. EVEN WITH LIGHT WINDS...THE CLEAR SKIES WILL PROMOTE
RADIATIONAL COOLING SATURDAY NIGHT SO COULD GET FAIRLY
COLD...ESPECIALLY IN AREAS WHERE THERE IS FRESH SNOW COVER. MODIFIED
THE PRIOR FORECAST ONLY SLIGHTLY AS IT SEEMED TO HAVE A DECENT
HANDLE ON THE COLDER TEMPERATURES.
WEAK RIDGING BRINGS TEMPERATURES UP SLIGHTLY FOR SUNDAY...BUT WITH
THE AIRMASS REMAINING COLD WITH 850MB TEMPERATURES AT -1C TO -6C
TEMPERATURES WILL LIKELY STAY NEAR OR BELOW FREEZING. THE ONGOING
FORECAST WILL KEEP HIGHS IN THE MID TO UPPER 20S. LOOKING FOR THE
ARCTIC FRONT MENTIONED EARLIER TO START PUSHING INTO NORTHERN
NEBRASKA BY 12Z MONDAY MORNING. THIS IS WHERE SOME DIFFERENCES LIE
THOUGH...MAINLY WITH THE TIMING OF THE SHORTWAVES THROUGH THE AREA.
THE GFS IS A BIT QUICKER TO MOVE THINGS THROUGH AND TOOK A SLOWER
APPROACH WHICH IS SHOWN BY BOTH THE ECMWF AND GEM. THE SYSTEM IN
QUESTION IS CURRENTLY OVER THE NORTHERN PACIFIC...MOVING TOWARDS THE
GULF OF ALASKA. THE MODELS DO AGREE THAT THIS SYSTEM WILL MOVE INTO
THE PACIFIC NORTHWEST SATURDAY NIGHT THE WILL DIG DOWN THE PACIFIC
COAST AND BECOME CLOSED OFF TUESDAY NIGHT INTO WEDNESDAY. AS THIS
OCCURS AN ADDITIONAL SHORTWAVE TROUGH THAT IS CURRENTLY PART OF THE
ORIGINAL SYSTEM WILL GET CAUGHT UP IN THE NORTHERN STREAM AND WILL
MOVE DOWN THROUGH THE NORTHERN AND CENTRAL PLAINS TUESDAY. THE
INITIAL COLD FRONT WILL MOVE ACROSS THE FORECAST AREA MONDAY
MORNING...WHICH DROPS 850MB TEMPERATURES DOWN TO NEAR -15C BY 18Z
MONDAY. THE PRESSURE GRADIENT WILL TIGHTEN BEHIND THE FRONT SO
ANTICIPATING WINDS TO INCREASE FOR MONDAY. THERE WILL ALSO BE A
CHANCE FOR SNOW BEHIND THE FRONT...HOWEVER WITH A GENERAL LACK OF
MOISTURE NOT EXPECTING QPF AMOUNTS TO BE SIGNIFICANT. THE BEST LIFT
IS SEEN ACROSS THE NORTHERN PART OF THE FORECAST AREA SUNDAY
NIGHT...THEN WEAKENS ACROSS THE CENTRAL AND EASTERN PART OF THE
AREA. SO WILL KEEP THE TREND FOR HIGHER PRECIPITATION CHANCES OVER
THE NORTHERN ZONES FOR EARLY MONDAY MORNING THEN TRANSITION TO THE
WESTERN HALF ON MONDAY...THEN TO THE SOUTHERN PART OF THE FORECAST
AREA FOR MONDAY NIGHT. AGAIN...QPF AMOUNTS DON/T LOOK TO BE TOO MUCH
SO AT MOST EXPECT A COUPLE INCHES OF SNOW.
THE BIG PUSH OF COLDER AIR WILL COME WITH THE TUESDAY SHORTWAVE
TROUGH MOVES IN. MODELS AREN/T QUITE AS COLD AS PRIOR RUNS WERE BUT
STILL DROP 850MB TEMPERATURES DOWN TO -20C OR COLDER FOR TUESDAY.
LOOKING AT ENSEMBLE GUIDANCE...ITS COMING INTO BETTER AGREEMENT FROM
YESTERDAYS RUN...AS THE 26.00 RUN FROM THE GFS ENSEMBLE NOW IS ONLY
GIVING A SPREAD OF 10 DEGREES FOR HIGHS RATHER THAN 30 AS WAS SEEN
YESTERDAY. IT DOES STILL LOOK LIKE TUESDAY AND TUESDAY NIGHT WILL BE
THE COLDEST PERIODS OF THE WEEK...HOWEVER THERE IS CONSIDERABLE
DIFFERENCES IN GOING THROUGH THE WEEK IN HOW MUCH AND WHERE THE COLD
AIR WILL BE SO ALTHOUGH HAVE HIGH CONFIDENCE THAT TEMPERATURES WILL
BE COLD...AND BELOW NORMAL...HOW MUCH BELOW NORMAL WILL REMAIN IN
QUESTION AT THIS TIME AND HAVE JUST KEPT THE TEMPERATURE TREND GOING
DOWNWARD IN THE FORECAST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1133 PM CST THU DEC 25 2014
ONE UPPER LEVEL DISTURBANCE WILL LIFT NORTH OF THE FORECAST AREA
OVERNIGHT...AND A SECOND WILL APPROACH SOUTHWESTERN AND CENTRAL
NEBRASKA FRIDAY MORNING INTO FRIDAY EVENING. FOR THE KLBF
TERMINAL...SOME PATCHY FREEZING DRIZZLE AND FOG IS POSSIBLE
THROUGH 10Z. CIGS WILL BE AROUND 1200 FT AGL...HOWEVER...THEY MAY
DROP AS LOW AS 800 FT AGL WITH ANY DRIZZLE OR FOG. LIGHT SNOW IS
POSSIBLE AFTER 14Z FRIDAY...AND WILL PERSIST OFF AND ON THROUGH
FRIDAY EVENING. VISBYS WILL GENERALLY BE AROUND 3SM WITH
SNOW...HOWEVER SOME MODERATE INTENSITY SNOW IS POSSIBLE LATE
MORNING FRIDAY WITH VISBYS DOWN TO 1SM AND CIGS AS LOW AS 900 FT
AGL. A SECONDARY SHOT OF LIGHT TO MODERATE INTENSITY SNOW IS
POSSIBLE FRIDAY EVENING WITH VISBYS AS LOW AS 1.5SM WITH CIGS AS
LOW AS 1000 FT AGL. FOR THE KVTN TERMINAL...LIGHT SNOW IS POSSIBLE
OVERNIGHT WITH VISBYS DOWN TO 3SM AND CIGS AS LOW AS 1200 FT AGL.
ON FRIDAY...BROKEN TO OVERCAST CIGS OF 1500 TO 2000 FT AGL ARE
POSSIBLE BY FRIDAY AFTERNOON...LIGHT SNOW WILL BE POSSIBLE WITH
VISBYS AS LOW AS 2SM.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 9 AM CST /8 AM MST/ THIS MORNING TO
MIDNIGHT CST /11 PM MST/ TONIGHT FOR NEZ025-026-036-037-057>059-
069>071.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR
NEZ027>029-038.
FREEZING RAIN ADVISORY UNTIL 9 AM CST THIS MORNING FOR NEZ006-
007.
WINTER WEATHER ADVISORY UNTIL NOON CST /11 AM MST/ TODAY FOR
NEZ004-005-022>024-035-056-094.
WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR NEZ009-
010.
WINTER WEATHER ADVISORY FROM NOON TODAY TO MIDNIGHT CST TONIGHT
FOR NEZ009-010.
&&
$$
SHORT TERM...CDC
LONG TERM...BROOKS
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1137 PM CST THU DEC 25 2014
.DISCUSSION...
SEE THE 06Z AVIATION DISCUSSION BELOW.
40
&&
.AVIATION...
DECENT MOISTURE ADVECTION OFF OF THE GULF AND A DEVELOPING LOW-
LEVEL JET WILL HELP DEVELOP MVFR CEILINGS OVER THE INLAND SITES
BETWEEN 09Z AND 12Z. THE MODELS WERE ALSO INTRODUCING ISOLATED
SHOWERS GENERALLY AFTER 17Z. THERE WAS ONE DIFFERENCE FROM THE
PREVIOUS MODEL RUNS...THE 00Z NAMBUFR WAS FORECASTING SLIGHTLY
HIGHER CEILINGS FRIDAY AFTERNOON...AND FELT THAT THERE WAS A GOOD
ENOUGH CHANCE TO INTRODUCE VFR CEILINGS FOR MOST INLAND LOCATIONS
DURING THE AFTERNOON. HOWEVER...MVFR CONDITIONS WILL LIKELY
REDEVELOP BETWEEN 22Z AND 00Z WITH IFR CONDITIONS POSSIBLE AFTER
00Z. SEA FOG MAY DEVELOP ALONG THE COAST AS THE DEWPOINTS RISE
INTO THE LOWER 60S AND MOVE OVER THE FAIRLY COOL CONTINENTAL SHELF
WATERS NEAR THE COAST. WITH THIS IN MIND...INTRODUCED THE
POSSIBILITY TO THE KGLS SITE AT 02Z.
40
&&
.PREV DISCUSSION... /ISSUED 937 PM CST THU DEC 25 2014/
UPDATE...
SEE DISCUSSION FOR EVENING UPDATE.
DISCUSSION...
CLOUD COVER HAS STARTED TO INCREASE TOWARDS THE CRP AREA THIS
EVENING AND IS STILL ON TRACK TO EXPAND IN COVERAGE ACROSS OUR
AREA THIS EVENING. A WEDGE OF VORTICITY EMBEDDED IN A SHORTWAVE
IS FORECASTED TO MOVE ACROSS THE WATERS TONIGHT AND MOVE OVER THE
TX/ LA BORDER TOMORROW MORNING. MOISTURE VALUES ARE STILL LIMITED
BUT LATEST HRRR RUN HAS A LINE OF SHOWERS FORMING THANKS TO THE
LIFT AND MOVING INLAND. GFS AND NAM FORECAST SOUNDINGS DO HAVE A
SATURATED LAYER UP TO AROUND 800 MB THOUGH. DUE TO THIS HAVE MADE
MINOR CHANGES TO POP GRIDS TO ACCOUNT FOR POTENTIAL OF SOME
SHOWERS FORMING THIS MORNING FROM THE SHORTWAVE. TOMORROW
AFTERNOON MODELS ARE AGAIN SHOWING STREAMER SHOWERS AND CURRENT
FORECAST HAS THIS COVERED. BESIDES MINOR CHANGES TO POP GRIDS FOR
THIS MORNING NO OTHER CHANGES REQUIRED AT THIS TIME. CURRENT
FORECAST IS ON TRACK. 23
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 52 70 60 64 42 / 10 30 40 60 30
HOUSTON (IAH) 52 72 63 72 47 / 10 30 50 70 50
GALVESTON (GLS) 59 70 64 70 53 / 10 30 40 70 60
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 6 AM CST FRIDAY FOR
THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS
FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...
WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL 6 AM CST FRIDAY FOR THE FOLLOWING
ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL
20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO
60 NM.
&&
$$
DISCUSSION...23
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
357 AM CST FRI DEC 26 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 357 AM CST FRI DEC 26 2014
CHALLENGES SURROUND SNOW CHANCES AND AMOUNTS TONIGHT INTO
SATURDAY WITH THE NEXT LOW PRESSURE SYSTEM. 26.00Z MODEL SUITE IN
GOOD AGREEMENT WITH THE SURFACE LOW TRACK...BUT DIFFER SOMEWHAT ON
THE PLACEMENT AND TIMING OF THE HIGHEST QPF. WILL LEAN TOWARD A
NAM/ECMWF BLEND WITH SUPPORT FROM THE SREF WHICH BEST MATCH
PRECIPITATION PLACEMENT WITH THE STRONGEST MID-LEVEL FORCING.
MAJORITY OF PRECIPITATION TODAY WILL REMAIN NORTH OF THE FORECAST
AREA ALONG TIGHT 850 TO 700 HPA THERMAL GRADIENT. ANYTHING THAT
DOES CREEP FAR ENOUGH SOUTH WILL LIKELY FALL AS DRIZZLE GIVEN WEAK
LIFT AND A DRY PROFILE ABOVE 1 TO 2 KM. TODAY WILL BE THE LAST
RELATIVELY MILD DAY FOR AWHILE WITH TEMPERATURES IN THE MID 30S
TO LOWER 40S.
PRECIPITATION EXPECTED TO DEVELOP RAPIDLY THIS EVENING AND
OVERNIGHT AS A SOUTHERN ROCKIES SHORT-WAVE MOVES INTO THE UPPER
MIDWEST AND INTERACTS WITH A SECONDARY WAVE DROPPING SOUTH ACROSS
THE SOUTHERN CANADIAN PRAIRIES. ASSOCIATED SURFACE LOW ACROSS
NORTHERN MO AT 27.06Z WILL RAPIDLY MOVE NORTH INTO SOUTHERN WI
SIX HOURS LATER. COLUMN TO QUICKLY SATURATE AND EXPECT DEFORMATION
PRECIPITATION AXIS FROM NORTHWEST IA INTO SOUTH-CENTRAL/SOUTHEAST
MN AND THEN INTO WEST-CENTRAL/NORTHERN WISCONSIN. THERMAL PROFILE
WILL BE COLD ENOUGH FOR ALL SNOW. LOWER SNOW RATIOS INITIALLY TO
RISE TO AROUND 14:1 BY SATURDAY MORNING WITH COOLING COLUMN. WITH
QPF AROUND TWO TO THREE TENTHS...EXPECT SNOW AMOUNTS TONIGHT
AROUND 1 TO 3 INCHES ALONG AND NORTHWEST OF A LINE FROM DODGE
CENTER TO WINONA TO WASSAU.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 357 AM CST FRI DEC 26 2014
LIGHT SNOW TO CONTINUE SATURDAY MORNING WITH AN ADDITIONAL 1 TO 2
INCHES POSSIBLE. WILL ISSUE A TWO-PART WINTER WEATHER ADVISORY FOR
2 TO 4 INCHES OF STORM TOTAL SNOW TONIGHT INTO SATURDAY. THE
FIRST PART INCLUDES DODGE/OLMSTED/WABASHA COUNTIES FROM 27.00Z TO
28.15Z AND THE SECOND PART FOR BUFFALO/TREMPALEAU/JACKSON/TAYLOR/
CLARK COUNTIES FROM 27.03Z TO 28.18Z. A TIGHT GRADIENT IN
SNOWFALL IS EXPECTED FROM NORTH TO SOUTH ACROSS THESE COUNTIES
WITH SLICK ROAD CONDITIONS POSSIBLE THROUGH THE EVENT. COLD FRONT
TO DROP ACROSS THE FORECAST AREA SATURDAY BEGINNING THE DECLINE IN
TEMPERATURES WITH HIGHS 5 TO 8 DEGREES COLDER THAN TODAY.
NORTHWEST WIND TO PICK-UP BEHIND THE FRONT WITH OCCASIONAL GUSTS
TO 20 MPH. LINGERING LIGHT SNOW TO EXIT THE AREA BY SATURDAY
EVENING.
SUNDAY THROUGH THURSDAY...SYNOPTIC REGIME SHIFTS TO DRIER
NORTHWEST FLOW ALOFT AS A BROAD TROUGH TAKES UP RESIDENCE ACROSS
HUDSON BAY. THIS BRINGS LOW SNOW CHANCES MONDAY AND AGAIN THURSDAY
AS SHORT-WAVES ROTATE AROUND THE PARENT TROUGH...BUT NOT EXPECTING
ANY SIGNIFICANT ACCUMULATIONS. BIGGER STORY WILL BE MUCH COLDER
CONDITIONS. TEMPERATURES TO DROP DAILY AND BOTTOM OUT ON TUESDAY
WITH HIGHS IN THE SINGLE DIGITS TO TEENS ABOVE ZERO. ASSUMING SOME
DEGREE OF CLEARING...MANY LOCATIONS TUESDAY/WEDNESDAY MORNINGS
LIKELY TO DROP BELOW ZERO. TEMPERATURES WILL MODERATE SOMEWHAT BY
LATE WEEK WITH HIGHS BACK INTO THE 20S AND LOWS IN THE SINGLE
DIGITS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1100 PM CST THU DEC 25 2014
A SFC TROUGH WILL TRACK SLOWLY EASTWARD ACROSS THE REGION
TONIGHT/FRIDAY...WITH AN UPPER LEVEL SHORTWAVE TROUGH SPINNING
ACROSS THE UPPER MISSISSIPPI RIVER VALLEY FRIDAY NIGHT. IFR-MVFR
CIGS ARE LOCATED POST THE SFC TROUGH...AND ANTICIPATE THESE WILL
SPREAD ACROSS KRST TOWARD 10Z...CLOSER TO 12Z FOR KLSE. DECENT
UPGLIDE ON THE LOW LEVEL ISENTROPIC SFCS COULD PRODUCED PATCHY AREAS
OF -DZ/FZDZ IN THE LOW CLOUD LAYER. NOT AS CONFIDENT AS EARLIER WITH
THIS OCCURRING THOUGH...WITH RAP BUFKIT SOUNDINGS AND EVEN THE NAM
NOT AS BULLISH ON THE POSSIBILITIES. WILL PULL MENTION AT KRST AS A
RESULT...AND LET SFC OBS/RADAR TRENDS DICTATE WHETHER IT NEEDS TO BE
ADDED BACK. NAM BUFKIT DOES SUGGEST -DZ COULD MOVE IN FOR THE
AFTERNOON. EXPECT SOME REDUCTIONS OF VSBY WITH LOW
CLOUDS...ESPECIALLY FOR THE HIGHER TERRAIN LOCATION OF KRST.
SNOW WILL SPREAD INTO THE REGION WITH THE SHORTWAVE FRIDAY
NIGHT...CONTINUING THROUGH SATURDAY MORNING. ANTICIPATED
ACCUMULATIONS FROM 1 TO 3 INCHES AT THIS TIME. VSBY RESTRICTIONS SUB
1-2SM WITH THE HEAVIER SNOWS. LIFR/IFR CIGS ALSO LIKELY FOR A PERIOD
BETWEEN 06-18Z SAT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO NOON CST
SATURDAY FOR WIZ017-029-032>034.
MN...WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 9 AM CST
SATURDAY FOR MNZ079-086-087.
IA...NONE.
&&
$$
SHORT TERM...ROGERS
LONG TERM...ROGERS
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1100 PM CST THU DEC 25 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 254 PM CST THU DEC 25 2014
MAIN FORECAST CONCERNS ARE ON LIGHT FREEZING DRIZZLE POTENTIAL
TONIGHT. FOCUS THEN TURNS TO SNOW ACCUMULATIONS FRIDAY NIGHT
THROUGH SATURDAY MORNING.
LIGHT FREEZING DRIZZLE OR SNOW IS POSSIBLE TONIGHT OVER PORTIONS OF
SOUTHEAST MINNESOTA INTO NORTH CENTRAL WISCONSIN. A MID LEVEL
TROUGH WILL PUSH EAST OUT OF THE DAKOTAS TONIGHT INTO FRIDAY
PRODUCING A BAND OF LIGHT SNOW AND POSSIBLY LIGHT FREEZING
DRIZZLE...MAINLY NORTHWEST OF THE FORECAST AREA. CONFIDENCE IS LOW
ON THE FREEZING DRIZZLE OCCURRING TONIGHT SO DECIDED TO KEEP IT
AS PROBABILITY INSTEAD OF COVERAGE. IF THE DRIZZLE DEVELOPS...SOME
VERY LIGHT ICING IS POSSIBLE ON UNTREATED ROADS AND ELEVATED
SURFACES. ALSO...MESOSCALE MODELS ARE SUGGESTING THE POTENTIAL FOR
SOME FOG TONIGHT RIGHT ALONG THE SURFACE TROUGH LATE TONIGHT INTO
FRIDAY MORNING. WILL HAVE TO KEEP AN EYE ON THIS DURING THE
EVENING AND OVERNIGHT HOURS. OTHERWISE PLAN ON LOWS FALLING INTO
THE UPPER 20S TO LOWER 30S TONIGHT.
ANOTHER TROUGH MOVES EAST OUT OF THE NORTHERN PLAINS FRIDAY AS A
SEPARATE TROUGH LIFTS NORTHEAST OUT OF THE SOUTHWEST CONUS. SNOW AND
RAIN LOOKS TO DEVELOP LATE FRIDAY AFTERNOON...INCREASING IN
COVERAGE GOING INTO FRIDAY NIGHT. OTHERWISE...PLAN ON MOSTLY
CLOUDY SKIES WITH AREAS OF DRIZZLE AND POSSIBLY SOME FOG ON FRIDAY
WITH HIGH TEMPERATURES RANGING FROM THE LOWER 30S OVER SOUTHEAST
MINNESOTA INTO NORTH CENTRAL WISCONSIN TO AROUND 40 ACROSS FAR
SOUTHWEST WISCONSIN.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 254 PM CST THU DEC 25 2014
BY FRIDAY EVENING...A BAND OF SNOW SHOULD BE IN PLACE FROM PORTIONS
OF NORTHEAST IOWA...SOUTHEAST MINNESOTA...INTO NORTH CENTRAL
WISCONSIN. A MIX OF RAIN OR SNOW IS EXPECTED ACROSS FAR NORTHEAST
IOWA INTO SOUTHWEST WISCONSIN. THERE IS UNCERTAINTY ON WHETHER OR
NOT THE SOUTHERN STREAM AND NORTHERN STREAM TROUGHS WILL INTERACT
ACROSS THE UPPER MISSISSIPPI RIVER VALLEY. THE NAM AND GFS OFFER
MORE PROGRESSIVE SOLUTIONS WHICH WOULD YIELD LIGHTER SNOWFALL
AMOUNTS. THE GEM AND ECMWF SOLUTIONS ARE MUCH STRONGER...AND
DEEPEN THE TROUGH OVER THE FORECAST AREA. IF THESE STRONGER
SOLUTIONS VERIFY...WE WOULD SEE SNOW ACCUMULATIONS IN THE 2 TO 4
INCH RANGE WITH HIGHER AMOUNTS POSSIBLE. EITHER WAY...TRAVEL WILL
BE IMPACTED BY THIS SYSTEM WITH SLIPPERY ROADS EXPECTED FRIDAY
NIGHT INTO SATURDAY MORNING. CONFIDENCE IS HIGH ON SEEING
ACCUMULATIONS IN THE 1 TO 2 INCH RANGE. LOW CONFIDENCE ON SEEING
AMOUNTS IN THE 2 TO 4 INCH PLUS RANGE AT THIS TIME.
THE STORM SYSTEM WILL EXIT THE REGION LATE SATURDAY AFTERNOON INTO
SATURDAY NIGHT WITH SEASONABLE TEMPERATURES EXPECTED THROUGH SUNDAY.
A MUCH COLDER AIRMASS THEN SWEEPS INTO THE REGION MONDAY AFTERNOON
INTO MONDAY NIGHT WITH TEMPERATURES PLUMMETING INTO THE SINGLE
DIGITS BELOW ZERO ACROSS MUCH OF THE REGION. SOME LIGHT SNOW IS
POSSIBLE MONDAY AFTERNOON MAINLY SOUTH OF INTERSTATE 90 AS A WEAK
SHORTWAVE MOVES THROUGH. OTHERWISE...THE MAIN FOCUS IS ON THE COLD
TEMPERATURES MOVING IN. HIGHS WILL ONLY BE IN THE SINGLE DIGITS
TO LOWER TEENS TUESDAY..WITH LOWS FALLING INTO THE SINGLE DIGITS
BELOW ZERO TUESDAY NIGHT. WIND CHILLS MAY ALSO BE A CONCERN MONDAY
NIGHT AND TUESDAY NIGHT OVER THE OPEN AREAS OF NORTHEAST IOWA...
SOUTHEAST MINNESOTA AND NORTH CENTRAL WISCONSIN WHERE WIND CHILL
VALUES COULD FALL TO AROUND -20.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1100 PM CST THU DEC 25 2014
A SFC TROUGH WILL TRACK SLOWLY EASTWARD ACROSS THE REGION
TONIGHT/FRIDAY...WITH AN UPPER LEVEL SHORTWAVE TROUGH SPINNING
ACROSS THE UPPER MISSISSIPPI RIVER VALLEY FRIDAY NIGHT. IFR-MVFR
CIGS ARE LOCATED POST THE SFC TROUGH...AND ANTICIPATE THESE WILL
SPREAD ACROSS KRST TOWARD 10Z...CLOSER TO 12Z FOR KLSE. DECENT
UPGLIDE ON THE LOW LEVEL ISENTROPIC SFCS COULD PRODUCED PATCHY AREAS
OF -DZ/FZDZ IN THE LOW CLOUD LAYER. NOT AS CONFIDENT AS EARLIER WITH
THIS OCCURRING THOUGH...WITH RAP BUFKIT SOUNDINGS AND EVEN THE NAM
NOT AS BULLISH ON THE POSSIBILITIES. WILL PULL MENTION AT KRST AS A
RESULT...AND LET SFC OBS/RADAR TRENDS DICTATE WHETHER IT NEEDS TO BE
ADDED BACK. NAM BUFKIT DOES SUGGEST -DZ COULD MOVE IN FOR THE
AFTERNOON. EXPECT SOME REDUCTIONS OF VSBY WITH LOW
CLOUDS...ESPECIALLY FOR THE HIGHER TERRAIN LOCATION OF KRST.
SNOW WILL SPREAD INTO THE REGION WITH THE SHORTWAVE FRIDAY
NIGHT...CONTINUING THROUGH SATURDAY MORNING. ANTICIPATED
ACCUMULATIONS FROM 1 TO 3 INCHES AT THIS TIME. VSBY RESTRICTIONS SUB
1-2SM WITH THE HEAVIER SNOWS. LIFR/IFR CIGS ALSO LIKELY FOR A PERIOD
BETWEEN 06-18Z SAT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM....WETENKAMP
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS PUEBLO CO
701 AM MST FRI DEC 26 2014
.UPDATE...
ISSUED AT 630 AM MST FRI DEC 26 2014
WHILE THE SNOW HAS BEEN SLOW TO DEVELOP OVER PORTIONS OF OUR
CWA...THE LOW PRESSURE SYSTEM IS JUST NOW MOVING INTO NW NM...JUST
SE OF THE 4 CORNERS REGION. LATEST HRRR GUIDANCE SHOWS A BAND OF
MODERATE SNOW MOVING UP FROM THE SOUTH BETWEEN 16Z AND 21Z THIS
MORNING AND AFTERNOON...COVERING MUCH OF THE SE PLAINS. SO...WILL
STAY THE COURSE DESPITE LACK OF ANY SIGNIFICANT ACCUMS AT THIS
POINT. ONE TO FOUR INCH ACCUMS STILL LOOK REASONABLE AT THIS
POINT. SOME 4 TO 6 INCH AMOUNTS POSSIBLE ESPECIALLY OVER THE
SANGRES AND SRN I-25 NR KTAD. KCOS MAY MISS OUT ON MUCH OF THE
SNOWFALL. ROSE
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 537 AM MST FRI DEC 26 2014
...COLD WITH SNOW SHOWERS TODAY...
UPPER LOW NOW OVER SRN UT IS SLOWLY TRANSLATING EWD THIS MORNING. AS
A REMINDER THAT DPROG DT IS NOT ALWAYS ON TARGET...THE TRACK AND
DEVELOPMENT OF THE LOW SEEMS TO BE REVERTING BACK TO MODEL RUNS FROM
SEVERAL DAYS AGO...BEFORE THE RECENT STRENGTHENING TREND IN THE
PROGS. SO...NOT EXPECTING ANY MAJOR SNOWFALL FROM THIS SYSTEM.
HOWEVER...ALL HI RES GUIDANCE CONTINUES TO SHOW A FAIRLY ROBUST BAND
OF SNOW DEVELOPING THROUGH THIS MORNING OVER THE SE PLAINS. IT LOOKS
LIKE THE HEAVIEST PRECIP WILL BE ASSOCIATED WITH A CONVERGENCE ZONE
ALONG AND TO THE SOUTH OF THE H7 LOW TRACK...WHICH IS EXPECTED TO BE
FROM AROUND KTAD MOVING NEWD TO S OF KITR BY LATE THIS AFTERNOON.
SO...BEST CHANCE OF DECENT SNOW ACCUMS WILL BE OUT OVER THE SE
PLAINS FROM AROUND 12Z TO 18Z...POSSIBLY LINGERING THROUGH THIS
AFTERNOON IF THE LOW CONTINUES TO STALL. NOT SEEING A PROLONGED
PERIOD OF UPSLOPE ALONG THE I-25 CORRIDOR...BUT COULD SEE A BRIEF
ROUND OF SOME MODT SNOW AS THE LOW TRACKS THROUGH ERN CO AND HT
WINDS BACK FOR A WHILE. AS MENTIONED IN AN EARLIER DISCUSSION...THE
INFAMOUS BROWN HOLE IN NRN PUEBLO AND SRN EL PASO COUNTIES MAY NOT
SEE MUCH SNOW...MAYBE ONLY AN INCH OR TWO IF THE BANDING DOESN`T
DEVELOP...BUT A FEW SPOTS FARTHER EAST AND SOUTH COULD STILL SEE
SOME DECENT ACCUMS IN THE 3-6 INCH RANGE. WILL JUST HAVE TO TAKE A
WAIT AND SEE APPROACH...BUT AT THIS TIME SEE NO REASON TO MAKE ANY
CHANGES TO THE ONGOING HIGHLIGHTS ESPECIALLY GIVEN THE POTENTIAL
HOLIDAY TRAVEL IMPACT ALONG ROUTES SUCH AS 50...160...AND 96.
OTHER STORY WILL BE THE MUCH COLDER AIR ARRIVING FROM THE NORTH.
LEADING EDGE OF THE MODIFIED ARCTIC AIR IS ARRIVING EARLY THIS
MORNING...AND H7 TEMPS WILL CONTINUE TO FALL FROM AROUND MINUS 10
THIS MORN TO MINUS 15 OR LOWER BY LATE AFTERNOON. SO...NOT EXPECTING
ANY REAL INCREASE IN TEMPS TODAY...IN FACT DEPENDING ON THE EXTENT
OF PRECIP WE COULD SEE FALLING TEMPS THROUGH THE DAY. HAVE CUT BACK
HIGH TEMPS OVER THE PLAINS BY A COUPLE DEGREES...AS WE WILL START
OUT CHILLY AND STAY THAT WAY TODAY. HIGH VALLEYS WILL SEE SIMILAR
HIGHS...IN THE 20S...ALONG WITH AREAS OF LIGHT TO MODT SNOW
THROUGHOUT THE CWA.
WILL START TO SEE PRECIP TAPER OFF AFTER 00Z THIS AFTERNOON...WITH
SOME LINGERING SN SHOWERS ESPECIALLY OVER THE HIGHER TRRN AND
PORTIONS OF THE SE PLAINS. MOST OF THE PRECIP SHOULD BE DONE BY 06Z
TONIGHT. COULD SEE SOME PARTIAL CLEARING BY EARLY SATURDAY
MORNING...AND IT WILL BE COLD...WITH LOWS TONIGHT IN THE SINGLE
DIGITS OVER THE PLAINS AND NEGATIVES FOR THE HIGH VALLEYS AND MT
AREAS. ROSE
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 537 AM MST FRI DEC 26 2014
PRIMARY LONGER TERM METEOROLOGICAL CONCERNS INCLUDE TEMPERATURES
AND POPS. LATEST REAL-TIME DATA...COMPUTER SIMULATIONS AND
FORECAST MODEL SOUNDINGS INDICATE THAT SYSTEM IMPACTING FORECAST
DISTRICT TODAY(FRIDAY) WILL BE DEPARTING THE CWFA SATURDAY
ALLOWING DRIER AND WARMER CONDITIONS(BUT STILL BELOW SEASONAL
TEMPERATURES) TO BE NOTED OVER THE MAJORITY OF SOUTHERN COLORADO
FROM SATURDAY INTO SUNDAY.
NEXT NORTHERLY TO NORTHEASTERLY COLD SURFACE SURGE(DRIVEN BY
1050+ MB SURFACE HIGH MOVING INTO NORTHERN MONTANA BY 00Z
TUESDAY) IS PROJECTED TO PRODUCE UNSEASONABLY COOL TO COLD
CONDITIONS...ESPECIALLY EASTERN SECTIONS...FROM MONDAY INTO AT
LEAST WEDNESDAY WITH SOME MODERATION IN TEMPERATURES ANTICIPATED
BY LATE WEEK.
IN ADDITION...UPPER DISTURBANCES IN COMBINATION WITH THE SURFACE
SURGE WILL BE CAPABLE OF PRODUCING UNSETTLED CONDITIONS(INCLUDING
THE POTENTIAL FOR ACCUMULATING SNOW) OVER MANY SECTIONS OF THE
FORECAST DISTRICT...ESPECIALLY FROM MONDAY INTO TUESDAY EVENING.
AS TOUCHED UPON BRIEFLY EARLIER...UNSEASONABLE COLD CONDITIONS ARE
ANTICIPATED FROM MONDAY INTO WEDNESDAY MORNING...WHERE MANY
LOCATIONS MAY STRUGGLE TO CLIMB OUT OF THE POSITIVE SINGLE DIGIT
TEMPERATURE READINGS DURING THIS TIME-FRAME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 657 AM MST FRI DEC 26 2014
HAVE MOVED UP TINING OF SHSN A BIT FOR THIS AFTERNOON. WITH THE
LOW PRESSURE SYSTEM MOVING A BIT SLOWER THAN EXPECTED. HEAVIEST
BAND OF SNOW SHOULD MOVE UP FROM THE SOUTH/RATON MESA AFTER
17Z...THEN IMPACT AREAS MAINLY S AND E OF KPUB. KPUB COULD BRIEFLY
GET INTO THE HEAVIER SHOWERS THIS AFTERNOON BEFORE THINGS MOVE E
AND DISSIPATE THIS EVE. SOME PRECIP STILL EXPECTED AT KCOS BUT
DOES NOT LOOK SIGNIFICANT...AND HAVE IMPROVED CONDITIONS SLIGHTLY
IN THE LATEST TAF AMD. KALS ALSO WILL LIKELY SEE PERIODS OF SHSN
THIS MORNING AND AFTERNOON...WITH MVFR-IFR CIGS AND VIS POSSIBLE.
ROSE
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 5 PM MST THIS AFTERNOON FOR
COZ058>067-069>080-083-085>089-093>099.
WINTER STORM WARNING UNTIL 5 PM MST THIS AFTERNOON FOR COZ068.
WINTER WEATHER ADVISORY UNTIL NOON MST TODAY FOR COZ081-082-084.
&&
$$
UPDATE...ROSE
AVIATION...ROSE
AREA FORECAST DISCUSSION
NWS PUEBLO CO
636 AM MST FRI DEC 26 2014
.UPDATE...
ISSUED AT 630 AM MST FRI DEC 26 2014
WHILE THE SNOW HAS BEEN SLOW TO DEVELOP OVER PORTIONS OF OUR
CWA...THE LOW PRESSURE SYSTEM IS JUST NOW MOVING INTO NW NM...JUST
SE OF THE 4 CORNERS REGION. LATEST HRRR GUIDANCE SHOWS A BAND OF
MODERATE SNOW MOVING UP FROM THE SOUTH BETWEEN 16Z AND 21Z THIS
MORNING AND AFTERNOON...COVERING MUCH OF THE SE PLAINS. SO...WILL
STAY THE COURSE DESPITE LACK OF ANY SIGNIFICANT ACCUMS AT THIS
POINT. ONE TO FOUR INCH ACCUMS STILL LOOK REASONABLE AT THIS
POINT. SOME 4 TO 6 INCH AMOUNTS POSSIBLE ESPECIALLY OVER THE
SANGRES AND SRN I-25 NR KTAD. KCOS MAY MISS OUT ON MUCH OF THE
SNOWFALL. ROSE
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 537 AM MST FRI DEC 26 2014
...COLD WITH SNOW SHOWERS TODAY...
UPPER LOW NOW OVER SRN UT IS SLOWLY TRANSLATING EWD THIS MORNING. AS
A REMINDER THAT DPROG DT IS NOT ALWAYS ON TARGET...THE TRACK AND
DEVELOPMENT OF THE LOW SEEMS TO BE REVERTING BACK TO MODEL RUNS FROM
SEVERAL DAYS AGO...BEFORE THE RECENT STRENGTHENING TREND IN THE
PROGS. SO...NOT EXPECTING ANY MAJOR SNOWFALL FROM THIS SYSTEM.
HOWEVER...ALL HI RES GUIDANCE CONTINUES TO SHOW A FAIRLY ROBUST BAND
OF SNOW DEVELOPING THROUGH THIS MORNING OVER THE SE PLAINS. IT LOOKS
LIKE THE HEAVIEST PRECIP WILL BE ASSOCIATED WITH A CONVERGENCE ZONE
ALONG AND TO THE SOUTH OF THE H7 LOW TRACK...WHICH IS EXPECTED TO BE
FROM AROUND KTAD MOVING NEWD TO S OF KITR BY LATE THIS AFTERNOON.
SO...BEST CHANCE OF DECENT SNOW ACCUMS WILL BE OUT OVER THE SE
PLAINS FROM AROUND 12Z TO 18Z...POSSIBLY LINGERING THROUGH THIS
AFTERNOON IF THE LOW CONTINUES TO STALL. NOT SEEING A PROLONGED
PERIOD OF UPSLOPE ALONG THE I-25 CORRIDOR...BUT COULD SEE A BRIEF
ROUND OF SOME MODT SNOW AS THE LOW TRACKS THROUGH ERN CO AND HT
WINDS BACK FOR A WHILE. AS MENTIONED IN AN EARLIER DISCUSSION...THE
INFAMOUS BROWN HOLE IN NRN PUEBLO AND SRN EL PASO COUNTIES MAY NOT
SEE MUCH SNOW...MAYBE ONLY AN INCH OR TWO IF THE BANDING DOESN`T
DEVELOP...BUT A FEW SPOTS FARTHER EAST AND SOUTH COULD STILL SEE
SOME DECENT ACCUMS IN THE 3-6 INCH RANGE. WILL JUST HAVE TO TAKE A
WAIT AND SEE APPROACH...BUT AT THIS TIME SEE NO REASON TO MAKE ANY
CHANGES TO THE ONGOING HIGHLIGHTS ESPECIALLY GIVEN THE POTENTIAL
HOLIDAY TRAVEL IMPACT ALONG ROUTES SUCH AS 50...160...AND 96.
OTHER STORY WILL BE THE MUCH COLDER AIR ARRIVING FROM THE NORTH.
LEADING EDGE OF THE MODIFIED ARCTIC AIR IS ARRIVING EARLY THIS
MORNING...AND H7 TEMPS WILL CONTINUE TO FALL FROM AROUND MINUS 10
THIS MORN TO MINUS 15 OR LOWER BY LATE AFTERNOON. SO...NOT EXPECTING
ANY REAL INCREASE IN TEMPS TODAY...IN FACT DEPENDING ON THE EXTENT
OF PRECIP WE COULD SEE FALLING TEMPS THROUGH THE DAY. HAVE CUT BACK
HIGH TEMPS OVER THE PLAINS BY A COUPLE DEGREES...AS WE WILL START
OUT CHILLY AND STAY THAT WAY TODAY. HIGH VALLEYS WILL SEE SIMILAR
HIGHS...IN THE 20S...ALONG WITH AREAS OF LIGHT TO MODT SNOW
THROUGHOUT THE CWA.
WILL START TO SEE PRECIP TAPER OFF AFTER 00Z THIS AFTERNOON...WITH
SOME LINGERING SN SHOWERS ESPECIALLY OVER THE HIGHER TRRN AND
PORTIONS OF THE SE PLAINS. MOST OF THE PRECIP SHOULD BE DONE BY 06Z
TONIGHT. COULD SEE SOME PARTIAL CLEARING BY EARLY SATURDAY
MORNING...AND IT WILL BE COLD...WITH LOWS TONIGHT IN THE SINGLE
DIGITS OVER THE PLAINS AND NEGATIVES FOR THE HIGH VALLEYS AND MT
AREAS. ROSE
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 537 AM MST FRI DEC 26 2014
PRIMARY LONGER TERM METEOROLOGICAL CONCERNS INCLUDE TEMPERATURES
AND POPS. LATEST REAL-TIME DATA...COMPUTER SIMULATIONS AND
FORECAST MODEL SOUNDINGS INDICATE THAT SYSTEM IMPACTING FORECAST
DISTRICT TODAY(FRIDAY) WILL BE DEPARTING THE CWFA SATURDAY
ALLOWING DRIER AND WARMER CONDITIONS(BUT STILL BELOW SEASONAL
TEMPERATURES) TO BE NOTED OVER THE MAJORITY OF SOUTHERN COLORADO
FROM SATURDAY INTO SUNDAY.
NEXT NORTHERLY TO NORTHEASTERLY COLD SURFACE SURGE(DRIVEN BY
1050+ MB SURFACE HIGH MOVING INTO NORTHERN MONTANA BY 00Z
TUESDAY) IS PROJECTED TO PRODUCE UNSEASONABLY COOL TO COLD
CONDITIONS...ESPECIALLY EASTERN SECTIONS...FROM MONDAY INTO AT
LEAST WEDNESDAY WITH SOME MODERATION IN TEMPERATURES ANTICIPATED
BY LATE WEEK.
IN ADDITION...UPPER DISTURBANCES IN COMBINATION WITH THE SURFACE
SURGE WILL BE CAPABLE OF PRODUCING UNSETTLED CONDITIONS(INCLUDING
THE POTENTIAL FOR ACCUMULATING SNOW) OVER MANY SECTIONS OF THE
FORECAST DISTRICT...ESPECIALLY FROM MONDAY INTO TUESDAY EVENING.
AS TOUCHED UPON BRIEFLY EARLIER...UNSEASONABLE COLD CONDITIONS ARE
ANTICIPATED FROM MONDAY INTO WEDNESDAY MORNING...WHERE MANY
LOCATIONS MAY STRUGGLE TO CLIMB OUT OF THE POSITIVE SINGLE DIGIT
TEMPERATURE READINGS DURING THIS TIME-FRAME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 537 AM MST FRI DEC 26 2014
IMPACT FOR THE TAF SITES IS NOT LOOKING QUITE AS GREAT
AS IT HAD EARLIER...BUT COULD STILL SEE SOME PERIODS OF MVFR TO IFR
ESPECIALLY AT KCOS...AND POTENTIALLY AT KPUB IF AREAS OF BANDED SNOW
TO THE E OF I-25 AND S OF HGWY 50 DRIFT A BIT FARTHER TO THE NW.
HIGHEST PRECIP CHANCES WILL BE IN THE 12Z-18Z TIME FRAME...THEN
PERIODS OF SHSN POSSIBLE THROUGH 03Z BEFORE GRADUAL IMPROVEMENT TO
VFR AFTER 06Z TONIGHT. ROSE
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 5 PM MST THIS AFTERNOON FOR
COZ058>067-069>080-083-085>089-093>099.
WINTER STORM WARNING UNTIL 5 PM MST THIS AFTERNOON FOR COZ068.
WINTER WEATHER ADVISORY UNTIL NOON MST TODAY FOR COZ081-082-084.
&&
$$
UPDATE...ROSE
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
718 AM CST FRI DEC 26 2014
.UPDATE...
ISSUED AT 715 AM CST FRI DEC 26 2014
THE SNOW HAS ENDED ACROSS WESTERN NEBRASKA. THE WINTER WEATHER
ADVISORY HAS BEEN CANCELLED IN THIS AREA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 358 AM CST FRI DEC 26 2014
SATELLITE AND THE RUC INDICATE A CLOSED H500 MB LOW MOVING ACROSS
THE FOUR CORNERS. A DEFORMATION BAND OF SNOW EXTENDED FROM NRN
COLO INTO WY WHICH WAS SHOWING SIGNS OF WEAKENING. A NEW
DEFORMATION BAND WAS DEVELOPING ACROSS NRN NM AND THIS DISTURBANCE
IS FCST BY THE MODELS TO LIFT THROUGH THE FCST AREA TODAY AND
TONIGHT AFFECTING AREAS ALONG AND EAST OF A LINE FROM KIML-KOGA-
KTIF-KONL. THE MODEL CONSENSUS SUGGESTS THE BEST SNOWFALL...4 TO 6
INCHES...WOULD LIFT FROM HAYES CENTER TO NORTH PLATTE AND THEN
NORTHEAST THROUGH BURWELL AND ONEILL. ROCK AND HOLT COUNTY HAVE
BEEN ADDED TO THE WINTER WEATHER ADVISORY IN EFFECT UNTIL 06Z
TONIGHT.
THE MODEL QPF IS MOST TIGHTLY CLUSTERED OVER NORTH PLATTE AND MODEL
QPF SPREAD INCREASES EAST AND WEST OF THAT POINT. WE ARE EXPECTING
AROUND 0.25 TO 0.33 INCHES OF QPF FROM THIS DISTURBANCE. THE GFS WAS
THE FIRST MODEL TWO DAYS AGO TO INDICATE A SEMI CLOSED H700MB LOW
LIFTING NORTHEAST THROUGH THE FCST AREA. THE OTHER MODELS CARRIED
THIS DISTURBANCE EAST MOSTLY THROUGH KS AND SCNTL/ERN NEB. NOW ALL
THE MODELS ARE IN AGREEMENT LIFTING THIS LOW THROUGH THE FCST AREA.
THERE IS SOME WOBBLING GOING ON WHICH IS NORMAL. THE RAP IS A BIT
EAST OF THE MODEL CONSENSUS. BUT GIVEN THE PERFORMANCE OF THE MODELS
YESTERDAY FAVORING THE CNTL PANHANDLE VS THE RAP WITH THE CHEYENNE
DIVIDE...THE MODEL CONSENSUS WINS THE FCST. GIVEN THE MODEL
CONSENSUS AND A 15 TO 1 RATIO...4 TO 6 INCHES OF SNOW APPEARS
LIKELY. THE 06Z NAM CONTINUES TO INDICATE THESE AMOUNTS FROM
KIML-KLBF-KBUB-KONL BUT SHOWS 6 TO 8 INCHES FROM KBBW-KBUB-KONL.
THIS IS A TREND IN THE MODELS FOR SLOWER DEVELOPMENT AND THE NAM
ACTUALLY HAS A CLOSED H700MB LOW OVER KGRI AT 03Z THIS EVENING WHILE
THE MODEL CONSENSUS WAS SHOWS THIS LOW AS AN OPEN WAVE. IF THIS
TREND CONTINUES AND A CLOSED H700MB LOW WERE TO TRAVERSE THE FCST
AREA...THE CHANCE OF HEAVY SNOW WOULD INCREASE.
FOR NOW THE FCST IS FOR 3 TO 6 INCHES OF SNOW IN THE ADVISORY AREA.
THIS IS AN INCREASE OF 2 INCHES OVER THE PREVIOUS FORECAST.
PATCHY FREEZING DRIZZLE CONTINUES THIS MORNING ASSOCIATED WITH
TRAPPED MOISTURE BELOW A 700MB DRY INTRUSION. THIS DRIZZLE IS
EXPECTED TO CLEAR THE FCST AREA 12Z-15Z THIS MORNING AND A CHECK OF
THE NEDOR WEBSITE INDICATES ROADS IN CUSTER COUNTY ARE COMPLETELY
COVERED WITH ICE...UNTREATED AND NO TRAVEL IS ADVISED SO THE
ADVISORY WILL BEGIN EARLIER IN THIS AREA. WITH QUICKLY CHANGING
AND DETERIORATING CONDITIONS...WILL ADD ADDITIONAL COUNTIES TO THE
ADVISORY TO THE NORTHEAST AND ISSUE A FREEZING RAIN ADVISORY FOR
FAR NORTH CENTRAL NEBRASKA THROUGH THIS MORNING.
THE MODELS INDICATE DRY AIR WILL WORK EAST TO HIGHWAY 83 AFTER
MIDNIGHT ALLOWING FOR A FEW TO SEVERAL HOURS OF MODEST RADIATIONAL
COOLING. LOWS TONIGHT ALONG AND WEST OF HIGHWAY 83 SHOULD FALL TO
NEAR OR BELOW ZERO IN MANY AREAS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 358 AM CST FRI DEC 26 2014
PRIMARY FORECAST CONCERNS FOR THIS PERIOD DEALS WITH TEMPERATURES
AS A COLDER AIRMASS STAYS IN PLACE ACROSS THE REGION...THEN WITH
AN INTRUDING ARCTIC COLD FRONT EARLY NEXT WEEK WHICH BRINGS AN
AIRMASS INTO THE AREA THAT IS COLDER YET ALONG WITH CHANCES FOR
SNOW.
MODELS ARE IN FAIRLY GOOD AGREEMENT WITH THE EVOLUTION OF THE UPPER
LEVEL PATTERN THROUGH THE NEXT WEEK WHICH LEADS TO SLIGHTLY ABOVE
AVERAGE CONFIDENCE IN THE FORECAST. THAT BEING SAID...THERE ARE
DIFFERENCES IN DETAILS OF INDIVIDUAL SHORTWAVE TROUGHS MOVING ACROSS
THE AREA WHICH DOES PROVIDE SOME UNCERTAINTY FOR PORTIONS OF THE
FORECAST.
BY SATURDAY MORNING THE SHORTWAVE TROUGH THAT WILL PUSH UP THROUGH
KANSAS AND EASTERN NEBRASKA WILL BE ON ITS WAY EAST OF THE REGION
WHILE A WEAK SHORTWAVE COMING OUT OF THE NORTHERN STREAM WILL PASS
ACROSS THE FORECAST AREA THROUGH THE DAY SATURDAY. BEHIND THIS
SHORTWAVE SUBSIDENCE WILL BE INCREASING WHICH SHOULD LEAD TO
CLEARING SKIES THROUGH THE DAY. HIGH PRESSURE AT THE SURFACE WILL
DRIFT TO THE SOUTHEAST THROUGH THE DAY AND SATURDAY NIGHT. SO
LOOKING FOR DECREASING WINDS...BUT AS IT WILL BE CENTERED SOUTH AND
EAST OF THE LOCAL AREA THE PRESSURE GRADIENT MAY KEEP WINDS FROM
GOING CALM. EVEN WITH LIGHT WINDS...THE CLEAR SKIES WILL PROMOTE
RADIATIONAL COOLING SATURDAY NIGHT SO COULD GET FAIRLY
COLD...ESPECIALLY IN AREAS WHERE THERE IS FRESH SNOW COVER. MODIFIED
THE PRIOR FORECAST ONLY SLIGHTLY AS IT SEEMED TO HAVE A DECENT
HANDLE ON THE COLDER TEMPERATURES.
WEAK RIDGING BRINGS TEMPERATURES UP SLIGHTLY FOR SUNDAY...BUT WITH
THE AIRMASS REMAINING COLD WITH 850MB TEMPERATURES AT -1C TO -6C
TEMPERATURES WILL LIKELY STAY NEAR OR BELOW FREEZING. THE ONGOING
FORECAST WILL KEEP HIGHS IN THE MID TO UPPER 20S. LOOKING FOR THE
ARCTIC FRONT MENTIONED EARLIER TO START PUSHING INTO NORTHERN
NEBRASKA BY 12Z MONDAY MORNING. THIS IS WHERE SOME DIFFERENCES LIE
THOUGH...MAINLY WITH THE TIMING OF THE SHORTWAVES THROUGH THE AREA.
THE GFS IS A BIT QUICKER TO MOVE THINGS THROUGH AND TOOK A SLOWER
APPROACH WHICH IS SHOWN BY BOTH THE ECMWF AND GEM. THE SYSTEM IN
QUESTION IS CURRENTLY OVER THE NORTHERN PACIFIC...MOVING TOWARDS THE
GULF OF ALASKA. THE MODELS DO AGREE THAT THIS SYSTEM WILL MOVE INTO
THE PACIFIC NORTHWEST SATURDAY NIGHT THE WILL DIG DOWN THE PACIFIC
COAST AND BECOME CLOSED OFF TUESDAY NIGHT INTO WEDNESDAY. AS THIS
OCCURS AN ADDITIONAL SHORTWAVE TROUGH THAT IS CURRENTLY PART OF THE
ORIGINAL SYSTEM WILL GET CAUGHT UP IN THE NORTHERN STREAM AND WILL
MOVE DOWN THROUGH THE NORTHERN AND CENTRAL PLAINS TUESDAY. THE
INITIAL COLD FRONT WILL MOVE ACROSS THE FORECAST AREA MONDAY
MORNING...WHICH DROPS 850MB TEMPERATURES DOWN TO NEAR -15C BY 18Z
MONDAY. THE PRESSURE GRADIENT WILL TIGHTEN BEHIND THE FRONT SO
ANTICIPATING WINDS TO INCREASE FOR MONDAY. THERE WILL ALSO BE A
CHANCE FOR SNOW BEHIND THE FRONT...HOWEVER WITH A GENERAL LACK OF
MOISTURE NOT EXPECTING QPF AMOUNTS TO BE SIGNIFICANT. THE BEST LIFT
IS SEEN ACROSS THE NORTHERN PART OF THE FORECAST AREA SUNDAY
NIGHT...THEN WEAKENS ACROSS THE CENTRAL AND EASTERN PART OF THE
AREA. SO WILL KEEP THE TREND FOR HIGHER PRECIPITATION CHANCES OVER
THE NORTHERN ZONES FOR EARLY MONDAY MORNING THEN TRANSITION TO THE
WESTERN HALF ON MONDAY...THEN TO THE SOUTHERN PART OF THE FORECAST
AREA FOR MONDAY NIGHT. AGAIN...QPF AMOUNTS DON/T LOOK TO BE TOO MUCH
SO AT MOST EXPECT A COUPLE INCHES OF SNOW.
THE BIG PUSH OF COLDER AIR WILL COME WITH THE TUESDAY SHORTWAVE
TROUGH MOVES IN. MODELS AREN/T QUITE AS COLD AS PRIOR RUNS WERE BUT
STILL DROP 850MB TEMPERATURES DOWN TO -20C OR COLDER FOR TUESDAY.
LOOKING AT ENSEMBLE GUIDANCE...ITS COMING INTO BETTER AGREEMENT FROM
YESTERDAYS RUN...AS THE 26.00 RUN FROM THE GFS ENSEMBLE NOW IS ONLY
GIVING A SPREAD OF 10 DEGREES FOR HIGHS RATHER THAN 30 AS WAS SEEN
YESTERDAY. IT DOES STILL LOOK LIKE TUESDAY AND TUESDAY NIGHT WILL BE
THE COLDEST PERIODS OF THE WEEK...HOWEVER THERE IS CONSIDERABLE
DIFFERENCES IN GOING THROUGH THE WEEK IN HOW MUCH AND WHERE THE COLD
AIR WILL BE SO ALTHOUGH HAVE HIGH CONFIDENCE THAT TEMPERATURES WILL
BE COLD...AND BELOW NORMAL...HOW MUCH BELOW NORMAL WILL REMAIN IN
QUESTION AT THIS TIME AND HAVE JUST KEPT THE TEMPERATURE TREND GOING
DOWNWARD IN THE FORECAST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 527 AM CST FRI DEC 26 2014
IFR/MVFR ALONG HIGHWAY 20 WEST OF VALENTINE AND HIGHWAY 2 WEST OF
THEDFORD MAY IMPROVE TO VFR THIS MORNING AS THE LAST SNOW LIFTS
NORTH AND HIGH PRESSURE BUILDS INTO THIS AREA. MVFR FROM KIML-
KANW/KONL IS EXPECTED TO LOWER TO IFR FROM SOUTH TO NORTH THIS
MORNING AND THIS AFTERNOON AS A DISTURBANCE ACROSS NM LIFTS
NORTHEAST THROUGH THE FCST AREA PRODUCING SNOW. IFR IS EXPECTED
THROUGH 03Z-06Z THIS EVENING ACROSS SWRN NEB INCLUDING KLBF WITH
AN IMPROVEMENT TO VFR BY 09Z. MVFR/IFR IS EXPECTED EAST OF HIGHWAY
83 TONIGHT AS SNOW CONTINUES IN THIS AREA.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST /11 PM MST/ TONIGHT
FOR NEZ025-026-036-037-057>059-069>071.
WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR NEZ009-
010.
WINTER WEATHER ADVISORY FROM NOON TODAY TO MIDNIGHT CST TONIGHT
FOR NEZ009-010.
FREEZING RAIN ADVISORY UNTIL 9 AM CST THIS MORNING FOR NEZ006-
007.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR
NEZ027>029-038.
&&
$$
UPDATE...CDC
SHORT TERM...CDC
LONG TERM...BROOKS
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
527 AM CST FRI DEC 26 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 358 AM CST FRI DEC 26 2014
SATELLITE AND THE RUC INDICATE A CLOSED H500 MB LOW MOVING ACROSS
THE FOUR CORNERS. A DEFORMATION BAND OF SNOW EXTENDED FROM NRN
COLO INTO WY WHICH WAS SHOWING SIGNS OF WEAKENING. A NEW
DEFORMATION BAND WAS DEVELOPING ACROSS NRN NM AND THIS DISTURBANCE
IS FCST BY THE MODELS TO LIFT THROUGH THE FCST AREA TODAY AND
TONIGHT AFFECTING AREAS ALONG AND EAST OF A LINE FROM KIML-KOGA-
KTIF-KONL. THE MODEL CONSENSUS SUGGESTS THE BEST SNOWFALL...4 TO 6
INCHES...WOULD LIFT FROM HAYES CENTER TO NORTH PLATTE AND THEN
NORTHEAST THROUGH BURWELL AND ONEILL. ROCK AND HOLT COUNTY HAVE
BEEN ADDED TO THE WINTER WEATHER ADVISORY IN EFFECT UNTIL 06Z
TONIGHT.
THE MODEL QPF IS MOST TIGHTLY CLUSTERED OVER NORTH PLATTE AND MODEL
QPF SPREAD INCREASES EAST AND WEST OF THAT POINT. WE ARE EXPECTING
AROUND 0.25 TO 0.33 INCHES OF QPF FROM THIS DISTURBANCE. THE GFS WAS
THE FIRST MODEL TWO DAYS AGO TO INDICATE A SEMI CLOSED H700MB LOW
LIFTING NORTHEAST THROUGH THE FCST AREA. THE OTHER MODELS CARRIED
THIS DISTURBANCE EAST MOSTLY THROUGH KS AND SCNTL/ERN NEB. NOW ALL
THE MODELS ARE IN AGREEMENT LIFTING THIS LOW THROUGH THE FCST AREA.
THERE IS SOME WOBBLING GOING ON WHICH IS NORMAL. THE RAP IS A BIT
EAST OF THE MODEL CONSENSUS. BUT GIVEN THE PERFORMANCE OF THE MODELS
YESTERDAY FAVORING THE CNTL PANHANDLE VS THE RAP WITH THE CHEYENNE
DIVIDE...THE MODEL CONSENSUS WINS THE FCST. GIVEN THE MODEL
CONSENSUS AND A 15 TO 1 RATIO...4 TO 6 INCHES OF SNOW APPEARS
LIKELY. THE 06Z NAM CONTINUES TO INDICATE THESE AMOUNTS FROM
KIML-KLBF-KBUB-KONL BUT SHOWS 6 TO 8 INCHES FROM KBBW-KBUB-KONL.
THIS IS A TREND IN THE MODELS FOR SLOWER DEVELOPMENT AND THE NAM
ACTUALLY HAS A CLOSED H700MB LOW OVER KGRI AT 03Z THIS EVENING WHILE
THE MODEL CONSENSUS WAS SHOWS THIS LOW AS AN OPEN WAVE. IF THIS
TREND CONTINUES AND A CLOSED H700MB LOW WERE TO TRAVERSE THE FCST
AREA...THE CHANCE OF HEAVY SNOW WOULD INCREASE.
FOR NOW THE FCST IS FOR 3 TO 6 INCHES OF SNOW IN THE ADVISORY AREA.
THIS IS AN INCREASE OF 2 INCHES OVER THE PREVIOUS FORECAST.
PATCHY FREEZING DRIZZLE CONTINUES THIS MORNING ASSOCIATED WITH
TRAPPED MOISTURE BELOW A 700MB DRY INTRUSION. THIS DRIZZLE IS
EXPECTED TO CLEAR THE FCST AREA 12Z-15Z THIS MORNING AND A CHECK OF
THE NEDOR WEBSITE INDICATES ROADS IN CUSTER COUNTY ARE COMPLETELY
COVERED WITH ICE...UNTREATED AND NO TRAVEL IS ADVISED SO THE
ADVISORY WILL BEGIN EARLIER IN THIS AREA. WITH QUICKLY CHANGING
AND DETERIORATING CONDITIONS...WILL ADD ADDITIONAL COUNTIES TO THE
ADVISORY TO THE NORTHEAST AND ISSUE A FREEZING RAIN ADVISORY FOR
FAR NORTH CENTRAL NEBRASKA THROUGH THIS MORNING.
THE MODELS INDICATE DRY AIR WILL WORK EAST TO HIGHWAY 83 AFTER
MIDNIGHT ALLOWING FOR A FEW TO SEVERAL HOURS OF MODEST RADIATIONAL
COOLING. LOWS TONIGHT ALONG AND WEST OF HIGHWAY 83 SHOULD FALL TO
NEAR OR BELOW ZERO IN MANY AREAS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 358 AM CST FRI DEC 26 2014
PRIMARY FORECAST CONCERNS FOR THIS PERIOD DEALS WITH TEMPERATURES
AS A COLDER AIRMASS STAYS IN PLACE ACROSS THE REGION...THEN WITH
AN INTRUDING ARCTIC COLD FRONT EARLY NEXT WEEK WHICH BRINGS AN
AIRMASS INTO THE AREA THAT IS COLDER YET ALONG WITH CHANCES FOR
SNOW.
MODELS ARE IN FAIRLY GOOD AGREEMENT WITH THE EVOLUTION OF THE UPPER
LEVEL PATTERN THROUGH THE NEXT WEEK WHICH LEADS TO SLIGHTLY ABOVE
AVERAGE CONFIDENCE IN THE FORECAST. THAT BEING SAID...THERE ARE
DIFFERENCES IN DETAILS OF INDIVIDUAL SHORTWAVE TROUGHS MOVING ACROSS
THE AREA WHICH DOES PROVIDE SOME UNCERTAINTY FOR PORTIONS OF THE
FORECAST.
BY SATURDAY MORNING THE SHORTWAVE TROUGH THAT WILL PUSH UP THROUGH
KANSAS AND EASTERN NEBRASKA WILL BE ON ITS WAY EAST OF THE REGION
WHILE A WEAK SHORTWAVE COMING OUT OF THE NORTHERN STREAM WILL PASS
ACROSS THE FORECAST AREA THROUGH THE DAY SATURDAY. BEHIND THIS
SHORTWAVE SUBSIDENCE WILL BE INCREASING WHICH SHOULD LEAD TO
CLEARING SKIES THROUGH THE DAY. HIGH PRESSURE AT THE SURFACE WILL
DRIFT TO THE SOUTHEAST THROUGH THE DAY AND SATURDAY NIGHT. SO
LOOKING FOR DECREASING WINDS...BUT AS IT WILL BE CENTERED SOUTH AND
EAST OF THE LOCAL AREA THE PRESSURE GRADIENT MAY KEEP WINDS FROM
GOING CALM. EVEN WITH LIGHT WINDS...THE CLEAR SKIES WILL PROMOTE
RADIATIONAL COOLING SATURDAY NIGHT SO COULD GET FAIRLY
COLD...ESPECIALLY IN AREAS WHERE THERE IS FRESH SNOW COVER. MODIFIED
THE PRIOR FORECAST ONLY SLIGHTLY AS IT SEEMED TO HAVE A DECENT
HANDLE ON THE COLDER TEMPERATURES.
WEAK RIDGING BRINGS TEMPERATURES UP SLIGHTLY FOR SUNDAY...BUT WITH
THE AIRMASS REMAINING COLD WITH 850MB TEMPERATURES AT -1C TO -6C
TEMPERATURES WILL LIKELY STAY NEAR OR BELOW FREEZING. THE ONGOING
FORECAST WILL KEEP HIGHS IN THE MID TO UPPER 20S. LOOKING FOR THE
ARCTIC FRONT MENTIONED EARLIER TO START PUSHING INTO NORTHERN
NEBRASKA BY 12Z MONDAY MORNING. THIS IS WHERE SOME DIFFERENCES LIE
THOUGH...MAINLY WITH THE TIMING OF THE SHORTWAVES THROUGH THE AREA.
THE GFS IS A BIT QUICKER TO MOVE THINGS THROUGH AND TOOK A SLOWER
APPROACH WHICH IS SHOWN BY BOTH THE ECMWF AND GEM. THE SYSTEM IN
QUESTION IS CURRENTLY OVER THE NORTHERN PACIFIC...MOVING TOWARDS THE
GULF OF ALASKA. THE MODELS DO AGREE THAT THIS SYSTEM WILL MOVE INTO
THE PACIFIC NORTHWEST SATURDAY NIGHT THE WILL DIG DOWN THE PACIFIC
COAST AND BECOME CLOSED OFF TUESDAY NIGHT INTO WEDNESDAY. AS THIS
OCCURS AN ADDITIONAL SHORTWAVE TROUGH THAT IS CURRENTLY PART OF THE
ORIGINAL SYSTEM WILL GET CAUGHT UP IN THE NORTHERN STREAM AND WILL
MOVE DOWN THROUGH THE NORTHERN AND CENTRAL PLAINS TUESDAY. THE
INITIAL COLD FRONT WILL MOVE ACROSS THE FORECAST AREA MONDAY
MORNING...WHICH DROPS 850MB TEMPERATURES DOWN TO NEAR -15C BY 18Z
MONDAY. THE PRESSURE GRADIENT WILL TIGHTEN BEHIND THE FRONT SO
ANTICIPATING WINDS TO INCREASE FOR MONDAY. THERE WILL ALSO BE A
CHANCE FOR SNOW BEHIND THE FRONT...HOWEVER WITH A GENERAL LACK OF
MOISTURE NOT EXPECTING QPF AMOUNTS TO BE SIGNIFICANT. THE BEST LIFT
IS SEEN ACROSS THE NORTHERN PART OF THE FORECAST AREA SUNDAY
NIGHT...THEN WEAKENS ACROSS THE CENTRAL AND EASTERN PART OF THE
AREA. SO WILL KEEP THE TREND FOR HIGHER PRECIPITATION CHANCES OVER
THE NORTHERN ZONES FOR EARLY MONDAY MORNING THEN TRANSITION TO THE
WESTERN HALF ON MONDAY...THEN TO THE SOUTHERN PART OF THE FORECAST
AREA FOR MONDAY NIGHT. AGAIN...QPF AMOUNTS DON/T LOOK TO BE TOO MUCH
SO AT MOST EXPECT A COUPLE INCHES OF SNOW.
THE BIG PUSH OF COLDER AIR WILL COME WITH THE TUESDAY SHORTWAVE
TROUGH MOVES IN. MODELS AREN/T QUITE AS COLD AS PRIOR RUNS WERE BUT
STILL DROP 850MB TEMPERATURES DOWN TO -20C OR COLDER FOR TUESDAY.
LOOKING AT ENSEMBLE GUIDANCE...ITS COMING INTO BETTER AGREEMENT FROM
YESTERDAYS RUN...AS THE 26.00 RUN FROM THE GFS ENSEMBLE NOW IS ONLY
GIVING A SPREAD OF 10 DEGREES FOR HIGHS RATHER THAN 30 AS WAS SEEN
YESTERDAY. IT DOES STILL LOOK LIKE TUESDAY AND TUESDAY NIGHT WILL BE
THE COLDEST PERIODS OF THE WEEK...HOWEVER THERE IS CONSIDERABLE
DIFFERENCES IN GOING THROUGH THE WEEK IN HOW MUCH AND WHERE THE COLD
AIR WILL BE SO ALTHOUGH HAVE HIGH CONFIDENCE THAT TEMPERATURES WILL
BE COLD...AND BELOW NORMAL...HOW MUCH BELOW NORMAL WILL REMAIN IN
QUESTION AT THIS TIME AND HAVE JUST KEPT THE TEMPERATURE TREND GOING
DOWNWARD IN THE FORECAST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 527 AM CST FRI DEC 26 2014
IFR/MVFR ALONG HIGHWAY 20 WEST OF VALENTINE AND HIGHWAY 2 WEST OF
THEDFORD MAY IMPROVE TO VFR THIS MORNING AS THE LAST SNOW LIFTS
NORTH AND HIGH PRESSURE BUILDS INTO THIS AREA. MVFR FROM KIML-
KANW/KONL IS EXPECTED TO LOWER TO IFR FROM SOUTH TO NORTH THIS
MORNING AND THIS AFTERNOON AS A DISTURBANCE ACROSS NM LIFTS
NORTHEAST THROUGH THE FCST AREA PRODUCING SNOW. IFR IS EXPECTED
THROUGH 03Z-06Z THIS EVENING ACROSS SWRN NEB INCLUDING KLBF WITH
AN IMPROVEMENT TO VFR BY 09Z. MVFR/IFR IS EXPECTED EAST OF HIGHWAY
83 TONIGHT AS SNOW CONTINUES IN THIS AREA.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 9 AM CST /8 AM MST/ THIS MORNING TO
MIDNIGHT CST /11 PM MST/ TONIGHT FOR NEZ025-026-036-037-057>059-
069>071.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR
NEZ027>029-038.
FREEZING RAIN ADVISORY UNTIL 9 AM CST THIS MORNING FOR NEZ006-
007.
WINTER WEATHER ADVISORY UNTIL NOON CST /11 AM MST/ TODAY FOR
NEZ004-005-022>024-035-056-094.
WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR NEZ009-
010.
WINTER WEATHER ADVISORY FROM NOON TODAY TO MIDNIGHT CST TONIGHT
FOR NEZ009-010.
&&
$$
SHORT TERM...CDC
LONG TERM...BROOKS
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS TULSA OK
1004 AM CST FRI DEC 26 2014
.DISCUSSION...
THE LATEST GUIDANCE FROM THE HRRR AND CURRENT OBSERVATIONS SUGGEST
HIGHS NEEDED UPWARD ADJUSTMENT IN SOME PLACES...AS LOW CLOUDS
HAVE BEEN SLOW TO PROGRESS NORTH INTO THE AREA. SOME BREAKS IN THE
CLOUDS ARE SHOWING UP ON SATELLITE...WHICH COULD ALLOW TEMPS TO
SHOOT UP INTO THE 60S IN SOME PLACES. STILL LOOKS LIKE THE BULK OF
ANY PRECIP WILL BE TONIGHT...POSSIBLY AS EARLY AS THIS AFTERNOON
IN THE SOUTH. THE FORECAST REFLECTS THIS AND WILL NOT BE ADJUSTED
AT THIS TIME.
LACY
&&
.PREV DISCUSSION... /ISSUED 546 AM CST FRI DEC 26 2014/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
CIGS 3-4K FEET EXPANDING NORTH ACROSS ENTIRE TAF AREA AND
LOWERING TO 15-25 HND FEET. SCATTERED RAIN BREAKING OUT THIS
AFTERNOON BECOMING MORE WIDESPREAD TONIGHT. ISOLATED THUNDER
LATE TONIGHT SOUTHEAST OK NOT EXPECTED TO IMPACT TAF SITES.
PREV DISCUSSION... /ISSUED 351 AM CST FRI DEC 26 2014/
DISCUSSION...
UPPER FLOW IS BACKING ACROSS THE AREA AHEAD OF THE DIGGING SYSTEM
NEAR THE FOUR CORNERS AREA. THE RESULT IS DEEP-LAYER SOUTHERLY
FLOW AND INCREASING MOISTURE. SATELLITE IMAGES SHOW LOW CLOUDS
DEVELOPING BENEATH THE STREAM OF HIGHER CLOUDS. THE COLD FRONT
ACROSS KANSAS IS EXPECTED TO MAKE RATHER SLOW PROGRESS SOUTHEAST
IN THIS SETUP AND WILL LIKELY NOT REACH OSAGE COUNTY UNTIL LATE
AFTERNOON. TEMPERATURES TODAY ARE TRICKY. IF THE CLOUDS THICKEN AS
EXPECTED THEN TEMPS WILL GENERALLY RISE 10 DEGREES OR LESS AND
STAY IN THE 50S. BUT ANY SIGNIFICANT SUN COULD PUSH READINGS
SEVERAL DEGREES HIGHER THAN THE CURRENT FORECAST.
SCATTERED PATCHES OF LIGHT RAIN WILL DEVELOP WITH TIME
TODAY...WITH FAIRLY WIDESPREAD RAIN IN THE AREA TONIGHT AS THE
COLD FRONT PUSHES THROUGH THE REGION. ELEVATED INSTABILITY
DEVELOPS AS FAR NORTH AS EXTREME SOUTHEAST OKLAHOMA TONIGHT AND AN
ISOLATED THUNDERSTORM IS POSSIBLE.
IT WILL BE A RACE BETWEEN THE ENDING PRECIP AND THE ARRIVAL OF
ENOUGH COLD AIR FOR A BRIEF WINTRY MIX. RIGHT NOW IT APPEARS THAT
A LITTLE SLEET OR A LITTLE SNOW COULD MIX WITH RAIN AS IT ENDS IN
FAR NORTHEAST OKLAHOMA VERY LATE TONIGHT OR EARLY ON SATURDAY
MORNING. THE BEST CHANCE OF ANY VERY LIGHT ACCUMULATION WOULD BE
IN FAR NORTHWEST OSAGE COUNTY...BUT GENERALLY NO ACCUMULATION IS
EXPECTED AT THIS TIME.
SEASONABLY COLD WEATHER WILL SETUP BEHIND THE CURRENT SYSTEM AND
PERSIST INTO MID NEXT WEEK.
TOWARD THE END OF NEXT WEEK...AROUND AND JUST AFTER THE FIRST OF
THE YEAR...MODEL GUIDANCE SHOWS A SIGNIFICANT SYSTEM CROSSING THE
MIDDLE OF THE COUNTRY WITH THE STORM TRACK OVER OR NEAR EASTERN
OKLAHOMA AND NORTHWEST ARKANSAS. THE CURRENT DATA SUGGESTS THAT
ENOUGH COULD AIR WILL BE IN PLACE FOR AT LEAST SOME WINTER WEATHER
POTENTIAL WITH THE BEGINNING OF THE PRECIPITATION. THE EVENTUAL
TRACK OF THE SYSTEM WILL DETERMINE HOW MUCH OF THE REGION GETS
INTO THE WARM SECTOR. OVERALL FORECAST CONFIDENCE IS VERY LOW AS
EXPECTED FOR A COMPLEX SYSTEM 7 DAYS AWAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 60 38 42 25 / 30 60 20 0
FSM 59 48 48 30 / 20 60 50 10
MLC 59 41 41 27 / 30 60 40 0
BVO 59 34 41 21 / 20 50 10 0
FYV 54 47 47 25 / 20 60 50 10
BYV 56 47 47 27 / 20 50 50 10
MKO 57 40 42 26 / 20 60 40 0
MIO 58 38 40 24 / 20 60 20 0
F10 56 38 42 25 / 20 50 30 0
HHW 58 48 48 30 / 30 70 40 10
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
SHORT TERM...30
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1044 AM MST FRI DEC 26 2014
.UPDATE...
ISSUED AT 1036 AM MST FRI DEC 26 2014
FORECAST REMAINS ON TRACK. UPPER LOW CENTER JUST NOW MOVING EAST
OF 4 CORNERS REGION...THROUGH NORTHWEST NEW MEXICO. SHOULD KEEP
ROUNDS OF LIGHT SNOW MOVING ACROSS THE REGION THROUGH THE
AFTERNOON. REINITIALIZED FRONT END GRIDS WITH LATEST OBSERVATIONS.
UPDATE ISSUED AT 630 AM MST FRI DEC 26 2014
WHILE THE SNOW HAS BEEN SLOW TO DEVELOP OVER PORTIONS OF OUR
CWA...THE LOW PRESSURE SYSTEM IS JUST NOW MOVING INTO NW NM...JUST
SE OF THE 4 CORNERS REGION. LATEST HRRR GUIDANCE SHOWS A BAND OF
MODERATE SNOW MOVING UP FROM THE SOUTH BETWEEN 16Z AND 21Z THIS
MORNING AND AFTERNOON...COVERING MUCH OF THE SE PLAINS. SO...WILL
STAY THE COURSE DESPITE LACK OF ANY SIGNIFICANT ACCUMULATIONS AT
THIS POINT. ONE TO FOUR INCH ACCUMULATIONS STILL LOOK REASONABLE
AT THIS POINT. SOME 4 TO 6 INCH AMOUNTS POSSIBLE ESPECIALLY OVER
THE SANGRES AND SRN I-25 NR KTAD. KCOS MAY MISS OUT ON MUCH OF THE
SNOWFALL. ROSE
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 537 AM MST FRI DEC 26 2014
...COLD WITH SNOW SHOWERS TODAY...
UPPER LOW NOW OVER SRN UT IS SLOWLY TRANSLATING EWD THIS MORNING. AS
A REMINDER THAT DPROG DT IS NOT ALWAYS ON TARGET...THE TRACK AND
DEVELOPMENT OF THE LOW SEEMS TO BE REVERTING BACK TO MODEL RUNS FROM
SEVERAL DAYS AGO...BEFORE THE RECENT STRENGTHENING TREND IN THE
PROGS. SO...NOT EXPECTING ANY MAJOR SNOWFALL FROM THIS SYSTEM.
HOWEVER...ALL HI RES GUIDANCE CONTINUES TO SHOW A FAIRLY ROBUST BAND
OF SNOW DEVELOPING THROUGH THIS MORNING OVER THE SE PLAINS. IT LOOKS
LIKE THE HEAVIEST PRECIP WILL BE ASSOCIATED WITH A CONVERGENCE ZONE
ALONG AND TO THE SOUTH OF THE H7 LOW TRACK...WHICH IS EXPECTED TO BE
FROM AROUND KTAD MOVING NORTHEASTWARD TO S OF KITR BY LATE THIS
AFTERNOON. SO...BEST CHANCE OF DECENT SNOW ACCUMULATIONS WILL BE
OUT OVER THE SE PLAINS FROM AROUND 12Z TO 18Z...POSSIBLY LINGERING
THROUGH THIS AFTERNOON IF THE LOW CONTINUES TO STALL. NOT SEEING A
PROLONGED PERIOD OF UPSLOPE ALONG THE I-25 CORRIDOR...BUT COULD
SEE A BRIEF ROUND OF SOME MODERATE SNOW AS THE LOW TRACKS THROUGH
ERN CO AND HT WINDS BACK FOR A WHILE. AS MENTIONED IN AN EARLIER
DISCUSSION...THE INFAMOUS BROWN HOLE IN NRN PUEBLO AND SRN EL PASO
COUNTIES MAY NOT SEE MUCH SNOW...MAYBE ONLY AN INCH OR TWO IF THE
BANDING DOESN`T DEVELOP...BUT A FEW SPOTS FARTHER EAST AND SOUTH
COULD STILL SEE SOME DECENT ACCUMULATIONS IN THE 3-6 INCH RANGE.
WILL JUST HAVE TO TAKE A WAIT AND SEE APPROACH...BUT AT THIS TIME
SEE NO REASON TO MAKE ANY CHANGES TO THE ONGOING HIGHLIGHTS
ESPECIALLY GIVEN THE POTENTIAL HOLIDAY TRAVEL IMPACT ALONG ROUTES
SUCH AS 50...160...AND 96.
OTHER STORY WILL BE THE MUCH COLDER AIR ARRIVING FROM THE NORTH.
LEADING EDGE OF THE MODIFIED ARCTIC AIR IS ARRIVING EARLY THIS
MORNING...AND H7 TEMPS WILL CONTINUE TO FALL FROM AROUND MINUS 10
THIS MORN TO MINUS 15 OR LOWER BY LATE AFTERNOON. SO...NOT EXPECTING
ANY REAL INCREASE IN TEMPS TODAY...IN FACT DEPENDING ON THE EXTENT
OF PRECIP WE COULD SEE FALLING TEMPS THROUGH THE DAY. HAVE CUT BACK
HIGH TEMPS OVER THE PLAINS BY A COUPLE DEGREES...AS WE WILL START
OUT CHILLY AND STAY THAT WAY TODAY. HIGH VALLEYS WILL SEE SIMILAR
HIGHS...IN THE 20S...ALONG WITH AREAS OF LIGHT TO MODERATE SNOW
THROUGHOUT THE CWA.
WILL START TO SEE PRECIP TAPER OFF AFTER 00Z THIS AFTERNOON...WITH
SOME LINGERING SN SHOWERS ESPECIALLY OVER THE HIGHER TERRAIN AND
PORTIONS OF THE SE PLAINS. MOST OF THE PRECIP SHOULD BE DONE BY 06Z
TONIGHT. COULD SEE SOME PARTIAL CLEARING BY EARLY SATURDAY
MORNING...AND IT WILL BE COLD...WITH LOWS TONIGHT IN THE SINGLE
DIGITS OVER THE PLAINS AND NEGATIVES FOR THE HIGH VALLEYS AND MT
AREAS. ROSE
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 537 AM MST FRI DEC 26 2014
PRIMARY LONGER TERM METEOROLOGICAL CONCERNS INCLUDE TEMPERATURES
AND POPS. LATEST REAL-TIME DATA...COMPUTER SIMULATIONS AND
FORECAST MODEL SOUNDINGS INDICATE THAT SYSTEM IMPACTING FORECAST
DISTRICT TODAY(FRIDAY) WILL BE DEPARTING THE CWA SATURDAY
ALLOWING DRIER AND WARMER CONDITIONS(BUT STILL BELOW SEASONAL
TEMPERATURES) TO BE NOTED OVER THE MAJORITY OF SOUTHERN COLORADO
FROM SATURDAY INTO SUNDAY.
NEXT NORTHERLY TO NORTHEASTERLY COLD SURFACE SURGE(DRIVEN BY
1050+ MB SURFACE HIGH MOVING INTO NORTHERN MONTANA BY 00Z
TUESDAY) IS PROJECTED TO PRODUCE UNSEASONABLY COOL TO COLD
CONDITIONS...ESPECIALLY EASTERN SECTIONS...FROM MONDAY INTO AT
LEAST WEDNESDAY WITH SOME MODERATION IN TEMPERATURES ANTICIPATED
BY LATE WEEK.
IN ADDITION...UPPER DISTURBANCES IN COMBINATION WITH THE SURFACE
SURGE WILL BE CAPABLE OF PRODUCING UNSETTLED CONDITIONS(INCLUDING
THE POTENTIAL FOR ACCUMULATING SNOW) OVER MANY SECTIONS OF THE
FORECAST DISTRICT...ESPECIALLY FROM MONDAY INTO TUESDAY EVENING.
AS TOUCHED UPON BRIEFLY EARLIER...UNSEASONABLE COLD CONDITIONS ARE
ANTICIPATED FROM MONDAY INTO WEDNESDAY MORNING...WHERE MANY
LOCATIONS MAY STRUGGLE TO CLIMB OUT OF THE POSITIVE SINGLE DIGIT
TEMPERATURE READINGS DURING THIS TIME-FRAME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1036 AM MST FRI DEC 26 2014
UPPER LOW JUST NOW MOVING EAST OF 4 CORNERS REGION THROUGH
NORTHWEST NEW MEXICO. SLOW MOVEMENT OF SYSTEM SHOULD KEEP THINGS
STATUS QUO THROUGH THE AFTERNOON INTO THE EVENING...WITH
IMPROVING CONDITIONS AFTER 06Z.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 5 PM MST THIS AFTERNOON FOR
COZ058>067-069>080-083-085>089-093>099.
WINTER STORM WARNING UNTIL 5 PM MST THIS AFTERNOON FOR COZ068.
WINTER WEATHER ADVISORY UNTIL NOON MST TODAY FOR COZ081-082-084.
&&
$$
UPDATE...LW
AVIATION...LW
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
401 PM CST FRI DEC 26 2014
.SHORT TERM...
238 PM CST
THROUGH SUNDAY...
AN UPPER LEVEL RIDGE AXIS STRETCHES FROM CUBA UP THE ATLANTIC COAST
WITH THE SURFACE HIGH OVER THE SOUTHEAST U.S. THE UPPER LEVEL RIDGE
SHIFTS VERY LITTLE THROUGH SATURDAY. A NARROW SURFACE TROUGH EXTENDS
FROM TEXAS THROUGH THE UPPER PENINSULA OF MICHIGAN THIS AFTERNOON. A
CLOSED LOW WILL FORM OVER THE MID MISSISSIPPI VALLEY TONIGHT AND
MOVE OVER NORTHERN IL LATE TONIGHT/EARLY SATURDAY MORNING BEFORE
MAKING IT TO QUEBEC SATURDAY EVENING. WEAK HIGH PRESSURE THEN
SPREADS OVER THE CWA SUNDAY.
TEMPERATURES CONTINUE TO CLIMB INTO THE UPPER 40S TO LOWER 50S THIS
AFTERNOON WITH THE MAJORITY OF THE CWA RECEIVING AMPLE SUNSHINE.
CLOUD COVER WILL INCREASE THIS EVENING AND OVERNIGHT AS THE LOW
TAKES SHAPE AND MOVES IN. WITH THE SURFACE LOW PASSING RIGHT
OVERHEAD...THINKING FOG OR DRIZZLE IS PROBABLE ESPECIALLY WEST OF A
MCHENRY TO JOLIET LINE. ONLY HAVE PATCHY FOG IN THE FORECAST...BUT
COULD SEE VSBYS IN SOME AREAS DROP TO AROUND OR LESS THAN ONE MILE
DUE TO FOG OR DRIZZLE.
RAIN/DRIZZLE MOVES IN FROM SOUTHWEST TO NORTHEAST LATE THIS
EVENING...AND LATEST RAP AND HRRR GUIDANCE INDICATE THE PRECIP WILL
MOVE IN QUICKER THAN PREVIOUSLY THOUGHT. IT LOOKS LIKE A GOOD HIGH
POP/LOW QPF SITUATION. HAVE AN INCREASING POP TREND FROM MIDNIGHT
THROUGH THE EARLY MORNING HOURS AS THE LOW MOVES OVERHEAD. LIGHT
RAIN SHIFTS EAST SATURDAY AFTERNOON AS THE LOW CONTINUES NORTHEAST.
GUSTY WEST WINDS ARE EXPECTED TOMORROW WITH GUSTS AROUND 30 MPH IN
THE AFTERNOON. TEMPERATURES WILL ALSO BE FALLING FROM THE LATE
MORNING HOURS ON BEHIND THE LOWS COLD FRONT. HOWEVER AREAS ALONG AND
EAST OF I-55 WILL SEE HIGH TEMPS IN THE MID 40S TO AROUND 50. TEMPS
FALL INTO THE 20S SATURDAY NIGHT.
LIGHT WINDS SHIFT TO OUT OF THE NORTHWEST OR NORTH SUNDAY WITH DRY
CONDITIONS EXPECTED. THE COOLER AIRMASS WILL KEEP HIGH TEMPS IN THE
30S...BUT WE SHOULD SEE SOME SUNSHINE.
JEE
&&
.LONG TERM...
238 PM CST
SUNDAY NIGHT THROUGH FRIDAY...
AN UPPER LEVEL LOW WILL SHIFT EAST OVER NORTHERN QUEBEC
SUNDAY...AND A VORTICITY STREAMER ASSOCIATED WITH THE LOW PUSHES
SOUTH THROUGH THE REGION MONDAY. ANOTHER TROUGH AXIS SWINGS THROUGH
WEDNESDAY. AT THE SURFACE...WEAK HIGH PRESSURE REMAINS OVER THE
REGION SUNDAY NIGHT. A COLD FRONT COINCIDED WITH THE VORT STREAMER
PUSHES THROUGH THE REGION MONDAY. ARCTIC HIGH PRESSURE FOLLOWS THE
COLD FRONT...AND FINALLY SHIFTS SOUTH TO THE GULF STATES THURSDAY.
CLOUDS INCREASE SUNDAY NIGHT AHEAD OF THE COLD FRONT WITH LOW TEMPS
IN THE 20S. FLURRIES AND LIGHT SNOW ARE EXPECTED ALONG THE COLD
FRONT AS MODELS CONTINUE TO FEATURE A LITTLE QPF. COLD AIR MASSES
SUCH AS THIS ONE CAN USUALLY SQUEEZE OUT ANY MOISTURE LINGERING IN
THE AIR SO HAVE HIGHER POPS WHERE MODELS FEATURED QPF AND FLURRIES
ACROSS THE REST OF THE CWA. NOT EXPECTING MUCH SNOW ACCUMULATION IF
ANY AT ALL. NORTH WINDS DOWN THE LAKE MAY RESULT IN LAKE EFFECT
SNOW OVER NW INDIANA MONDAY NIGHT INTO TUESDAY. COULD SEE A COUPLE
TENTHS OF AN INCH OF SNOW.
THE BIGGER IMPACT WILL BE TEMPERATURES. HIGH TEMPS WILL BE IN THE
LOWER 30S MONDAY THEN ONLY IN THE UPPER TEENS TO MID 20S TUESDAY.
LOW TEMPS TUESDAY WILL BE VARY FROM THE SINGLE DIGITS OVER NORTH
CENTRAL IL TO AROUND 10 DEGREES OVER NORTHWEST INDIANA. BRISK NW
WINDS WILL CREATE BELOW ZERO WINDCHILLS TUESDAY NIGHT INTO WEDNESDAY
MORNING. THE WHOLE CWA FEELS THE CHILL WEDNESDAY WITH HIGH TEMPS
AROUND 20 DEGREES BUT GUSTY WEST WINDS WILL MAKE IT FEEL LIKE IT IS
IN THE SINGLE DIGITS.
THE CENTER OF THE HIGH SHIFTS SOUTH OF THE REGION THURSDAY ALLOWING
TEMPS TO WARM SLIGHTLY INTO THE UPPER 20S THURSDAY. LONG RANGE
GUIDANCE THEN FEATURES A LOW PRESSURE SYSTEM MOVING UP THE OHIO
RIVER VALLEY LATE NEXT WEEK. GUIDANCE HAS THE SYSTEM BRINGING US
SNOW OVER THE WEEKEND...SO WILL KEEP AN EYE ON THIS SYSTEM.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* MVFR CIGS DEVELOPING THIS EVENING AND LOWERING TO IFR OVERNIGHT.
* CHANCE OF LIGHT RAIN OR DRIZZLE OVERNIGHT INTO SATURDAY MORNING.
* STRONG/GUSTY WESTERLY WINDS LATE SATURDAY MORNING INTO SATURDAY
AFTERNOON.
MDB
//DISCUSSION...UPDATED 22Z...
STREAKS OF MVFR STRATUS CONTINUE TO DEVELOP/EXPAND NORTHEASTWARD
INTO NORTHERN IL AND NORTHWEST IN. EXPECT INTERMITTENT SCT-BKN
COVERAGE AS THEY DEVELOP IN THE 025-030 RANGE OVER THE NEXT FEW
HOURS WITH EXPANSION TO MORE SOLID COVERAGE INTO THE EVENING WITH
BASES ALSO LOWERING.
MDB
FROM 18Z...
A WEAK FRONTAL BOUNDARY EXTENDS FROM NORTHEAST WISCONSIN SOUTHWEST
INTO THE PLAINS. AS THIS BOUNDARY SLOWLY MOVES EAST TODAY...NEW
LOW PRESSURE WILL DEVELOP OVER MISSOURI AND LIFT NORTHEAST ACROSS
NORTHWEST ILLINOIS SATURDAY MORNING AND THEN CONTINUE NORTHEAST
ACROSS LAKE MICHIGAN SATURDAY AFTERNOON. SOUTHERLY WINDS WILL
CONTINUE TODAY AND TONIGHT AHEAD OF THIS LOW WITH SOME GUSTS INTO
THE UPPER TEEN/LOWER 20KT RANGE POSSIBLE THIS AFTERNOON. WINDS
WILL SHIFT TO THE WEST AS THE LOW DEPARTS AND QUICKLY INCREASE
LATE SATURDAY MORNING INTO SATURDAY AFTERNOON...WHEN THERE COULD
BE A FEW HOUR PERIOD OF GUSTS TO 30 KT...BEFORE RELAXING BACK
INTO THE MID 20KT RANGE THROUGH SUNSET SATURDAY EVENING.
CIGS RANGING FROM 2KFT TO 4KFT ARE SPREADING NORTH INTO SOUTHERN
MISSOURI AND SOUTHERN ILLINOIS LATE THIS MORNING. THIS CLOUD COVER
IS EXPECTED TO CONTINUE NORTH ACROSS THE TERMINALS LATE THIS
AFTERNOON INTO THIS EVENING THEN SLOWLY LOWER...EVENTUALLY INTO
IFR OVERNIGHT. OVERALL CONFIDENCE IN THIS TREND IS HIGH BUT THE
TIMING AND SPECIFIC CIGS WILL LIKELY REQUIRE TWEAKS WITH LATER
FORECASTS. AS THE LOW APPROACHES...ITS POSSIBLE THAT CIGS COULD
LOWER INTO LIFR...ESPECIALLY AT RFD. CIGS WILL THEN LIFT INTO MVFR
AS THE LOW DEPARTS AND POSSIBLY BECOME VFR SATURDAY AFTERNOON.
CONFIDENCE REGARDING PRECIP OVERNIGHT INTO SATURDAY MORNING IS
SOMEWHAT LOW. PRECIP AMOUNTS LOOK FAIRLY LIGHT BUT COULD BE A
PERIOD OF VERY LIGHT RAIN OR DRIZZLE. OPTED TO MAINTAIN CURRENT
RAIN/DRIZZLE MENTION FOR NOW. VISIBILITIES WILL ALSO LIKELY LOWER
INTO MVFR AS LOW LEVEL MOISTURE INCREASES AND IF DRIZZLE BECOMES
PREVAILING...IN ADDITION TO THE APPROACHING LOW PRESSURE...VIS
COULD EASILY DROP TO 1-2SM WITH SOME DENSE FOG POSSIBLE. CMS
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* HIGH FOR CIG TRENDS...MEDIUM FOR TIMING AND SPECIFIC HEIGHTS.
* MEDIUM FOR LIGHT RAIN OR DRIZZLE OVERNIGHT/SATURDAY MORNING.
* HIGH FOR WINDS THRU THE PERIOD...MEDIUM FOR TIMING CHANGES.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...MVFR CIGS WITH BREEZY NW WINDS.
SUNDAY...VFR.
MONDAY...SCHC -SHSN. MVFR PSBL. N TO NE WINDS.
TUESDAY...VFR. GUSTY NW WINDS.
WEDNESDAY AND THURSDAY...VFR. BREEZY SW WINDS AT TIMES.
KMD
&&
.MARINE...
324 PM CST
A TROUGH OF LOW PRESSURE MOVING ACROSS THE REGION IS HELPING TO
PROVIDE SIGNIFICANT DIFFERENCES WITH WIND SPEED AND DIRECTION
ACROSS THE ENTIRE LAKE THIS AFTERNOON...AND EXPECT THESE
DIFFERENCES TO REMAIN IN PLACE TONIGHT INTO SATURDAY MORNING.
WHILE SOUTHERLY FLOW REMAINS IN PLACE OVER THE SOUTHERN HALF OF
THE LAKE...SOUTHERLY WINDS OVER THE NORTHERN HALF ARE ALREADY
SLOWLY BECOMING MORE NORTHERLY AS THIS TROUGH MOVES ACROSS THE
LAKE. THIS TREND WILL CONTINUE OVER THE NORTHERN HALF TONIGHT WITH
MORE NORTHERLY WINDS EXPECTED LATER TONIGHT...WHILE SOUTHERLY
WINDS PERSIST OVER THE SOUTHERN HALF. NEW LOW PRESSURE WILL THEN
DEVELOP ALONG THIS TROUGH/BOUNDARY EARLY SATURDAY MORNING AND MOVE
ACROSS THE LAKE SATURDAY. EXPECT SPEEDS TO INCREASE DURING THE DAY
AS WINDS BECOME MORE WESTERLY IN THE AFTERNOON...AND THEN
NORTHWEST IN THE EVENING. EXPECT SPEEDS TO THEN DIMINISH SATURDAY
NIGHT INTO SUNDAY AS THIS LOW DEPARTS AND HIGH PRESSURE BUILDS
ACROSS THE REGION.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ744-LMZ745...10 AM SATURDAY TO 4 AM
SUNDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743...10 AM
SATURDAY TO 10 PM SATURDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
324 PM CST FRI DEC 26 2014
.SHORT TERM...
238 PM CST
THROUGH SUNDAY...
AN UPPER LEVEL RIDGE AXIS STRETCHES FROM CUBA UP THE ATLANTIC COAST
WITH THE SURFACE HIGH OVER THE SOUTHEAST U.S. THE UPPER LEVEL RIDGE
SHIFTS VERY LITTLE THROUGH SATURDAY. A NARROW SURFACE TROUGH EXTENDS
FROM TEXAS THROUGH THE UPPER PENINSULA OF MICHIGAN THIS AFTERNOON. A
CLOSED LOW WILL FORM OVER THE MID MISSISSIPPI VALLEY TONIGHT AND
MOVE OVER NORTHERN IL LATE TONIGHT/EARLY SATURDAY MORNING BEFORE
MAKING IT TO QUEBEC SATURDAY EVENING. WEAK HIGH PRESSURE THEN
SPREADS OVER THE CWA SUNDAY.
TEMPERATURES CONTINUE TO CLIMB INTO THE UPPER 40S TO LOWER 50S THIS
AFTERNOON WITH THE MAJORITY OF THE CWA RECEIVING AMPLE SUNSHINE.
CLOUD COVER WILL INCREASE THIS EVENING AND OVERNIGHT AS THE LOW
TAKES SHAPE AND MOVES IN. WITH THE SURFACE LOW PASSING RIGHT
OVERHEAD...THINKING FOG OR DRIZZLE IS PROBABLE ESPECIALLY WEST OF A
MCHENRY TO JOLIET LINE. ONLY HAVE PATCHY FOG IN THE FORECAST...BUT
COULD SEE VSBYS IN SOME AREAS DROP TO AROUND OR LESS THAN ONE MILE
DUE TO FOG OR DRIZZLE.
RAIN/DRIZZLE MOVES IN FROM SOUTHWEST TO NORTHEAST LATE THIS
EVENING...AND LATEST RAP AND HRRR GUIDANCE INDICATE THE PRECIP WILL
MOVE IN QUICKER THAN PREVIOUSLY THOUGHT. IT LOOKS LIKE A GOOD HIGH
POP/LOW QPF SITUATION. HAVE AN INCREASING POP TREND FROM MIDNIGHT
THROUGH THE EARLY MORNING HOURS AS THE LOW MOVES OVERHEAD. LIGHT
RAIN SHIFTS EAST SATURDAY AFTERNOON AS THE LOW CONTINUES NORTHEAST.
GUSTY WEST WINDS ARE EXPECTED TOMORROW WITH GUSTS AROUND 30 MPH IN
THE AFTERNOON. TEMPERATURES WILL ALSO BE FALLING FROM THE LATE
MORNING HOURS ON BEHIND THE LOWS COLD FRONT. HOWEVER AREAS ALONG AND
EAST OF I-55 WILL SEE HIGH TEMPS IN THE MID 40S TO AROUND 50. TEMPS
FALL INTO THE 20S SATURDAY NIGHT.
LIGHT WINDS SHIFT TO OUT OF THE NORTHWEST OR NORTH SUNDAY WITH DRY
CONDITIONS EXPECTED. THE COOLER AIRMASS WILL KEEP HIGH TEMPS IN THE
30S...BUT WE SHOULD SEE SOME SUNSHINE.
JEE
&&
.LONG TERM...
238 PM CST
SUNDAY NIGHT THROUGH FRIDAY...
AN UPPER LEVEL LOW WILL SHIFT EAST OVER NORTHERN QUEBEC
SUNDAY...AND A VORTICITY STREAMER ASSOCIATED WITH THE LOW PUSHES
SOUTH THROUGH THE REGION MONDAY. ANOTHER TROUGH AXIS SWINGS THROUGH
WEDNESDAY. AT THE SURFACE...WEAK HIGH PRESSURE REMAINS OVER THE
REGION SUNDAY NIGHT. A COLD FRONT COINCIDED WITH THE VORT STREAMER
PUSHES THROUGH THE REGION MONDAY. ARCTIC HIGH PRESSURE FOLLOWS THE
COLD FRONT...AND FINALLY SHIFTS SOUTH TO THE GULF STATES THURSDAY.
CLOUDS INCREASE SUNDAY NIGHT AHEAD OF THE COLD FRONT WITH LOW TEMPS
IN THE 20S. FLURRIES AND LIGHT SNOW ARE EXPECTED ALONG THE COLD
FRONT AS MODELS CONTINUE TO FEATURE A LITTLE QPF. COLD AIR MASSES
SUCH AS THIS ONE CAN USUALLY SQUEEZE OUT ANY MOISTURE LINGERING IN
THE AIR SO HAVE HIGHER POPS WHERE MODELS FEATURED QPF AND FLURRIES
ACROSS THE REST OF THE CWA. NOT EXPECTING MUCH SNOW ACCUMULATION IF
ANY AT ALL. NORTH WINDS DOWN THE LAKE MAY RESULT IN LAKE EFFECT
SNOW OVER NW INDIANA MONDAY NIGHT INTO TUESDAY. COULD SEE A COUPLE
TENTHS OF AN INCH OF SNOW.
THE BIGGER IMPACT WILL BE TEMPERATURES. HIGH TEMPS WILL BE IN THE
LOWER 30S MONDAY THEN ONLY IN THE UPPER TEENS TO MID 20S TUESDAY.
LOW TEMPS TUESDAY WILL BE VARY FROM THE SINGLE DIGITS OVER NORTH
CENTRAL IL TO AROUND 10 DEGREES OVER NORTHWEST INDIANA. BRISK NW
WINDS WILL CREATE BELOW ZERO WINDCHILLS TUESDAY NIGHT INTO WEDNESDAY
MORNING. THE WHOLE CWA FEELS THE CHILL WEDNESDAY WITH HIGH TEMPS
AROUND 20 DEGREES BUT GUSTY WEST WINDS WILL MAKE IT FEEL LIKE IT IS
IN THE SINGLE DIGITS.
THE CENTER OF THE HIGH SHIFTS SOUTH OF THE REGION THURSDAY ALLOWING
TEMPS TO WARM SLIGHTLY INTO THE UPPER 20S THURSDAY. LONG RANGE
GUIDANCE THEN FEATURES A LOW PRESSURE SYSTEM MOVING UP THE OHIO
RIVER VALLEY LATE NEXT WEEK. GUIDANCE HAS THE SYSTEM BRINGING US
SNOW OVER THE WEEKEND...SO WILL KEEP AN EYE ON THIS SYSTEM.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* MVFR CIGS DEVELOPING THIS EVENING AND LOWERING TO IFR OVERNIGHT.
* CHANCE OF LIGHT RAIN OR DRIZZLE OVERNIGHT INTO SATURDAY MORNING.
* GUSTY SOUTH/SOUTHWEST WINDS THIS AFTERNOON.
* STRONG/GUSTY WESTERLY WINDS LATE SATURDAY MORNING INTO SATURDAY
AFTERNOON. CMS
//DISCUSSION...UPDATED 18Z...
A WEAK FRONTAL BOUNDARY EXTENDS FROM NORTHEAST WISCONSIN SOUTHWEST
INTO THE PLAINS. AS THIS BOUNDARY SLOWLY MOVES EAST TODAY...NEW
LOW PRESSURE WILL DEVELOP OVER MISSOURI AND LIFT NORTHEAST ACROSS
NORTHWEST ILLINOIS SATURDAY MORNING AND THEN CONTINUE NORTHEAST
ACROSS LAKE MICHIGAN SATURDAY AFTERNOON. SOUTHERLY WINDS WILL
CONTINUE TODAY AND TONIGHT AHEAD OF THIS LOW WITH SOME GUSTS INTO
THE UPPER TEEN/LOWER 20KT RANGE POSSIBLE THIS AFTERNOON. WINDS
WILL SHIFT TO THE WEST AS THE LOW DEPARTS AND QUICKLY INCREASE
LATE SATURDAY MORNING INTO SATURDAY AFTERNOON...WHEN THERE COULD
BE A FEW HOUR PERIOD OF GUSTS TO 30 KT...BEFORE RELAXING BACK
INTO THE MID 20KT RANGE THROUGH SUNSET SATURDAY EVENING.
CIGS RANGING FROM 2KFT TO 4KFT ARE SPREADING NORTH INTO SOUTHERN
MISSOURI AND SOUTHERN ILLINOIS LATE THIS MORNING. THIS CLOUD COVER
IS EXPECTED TO CONTINUE NORTH ACROSS THE TERMINALS LATE THIS
AFTERNOON INTO THIS EVENING THEN SLOWLY LOWER...EVENTUALLY INTO
IFR OVERNIGHT. OVERALL CONFIDENCE IN THIS TREND IS HIGH BUT THE
TIMING AND SPECIFIC CIGS WILL LIKELY REQUIRE TWEAKS WITH LATER
FORECASTS. AS THE LOW APPROACHES...ITS POSSIBLE THAT CIGS COULD
LOWER INTO LIFR...ESPECIALLY AT RFD. CIGS WILL THEN LIFT INTO MVFR
AS THE LOW DEPARTS AND POSSIBLY BECOME VFR SATURDAY AFTERNOON.
CONFIDENCE REGARDING PRECIP OVERNIGHT INTO SATURDAY MORNING IS
SOMEWHAT LOW. PRECIP AMOUNTS LOOK FAIRLY LIGHT BUT COULD BE A
PERIOD OF VERY LIGHT RAIN OR DRIZZLE. OPTED TO MAINTAIN CURRENT
RAIN/DRIZZLE MENTION FOR NOW. VISIBILITIES WILL ALSO LIKELY LOWER
INTO MVFR AS LOW LEVEL MOISTURE INCREASES AND IF DRIZZLE BECOMES
PREVAILING...IN ADDITION TO THE APPROACHING LOW PRESSURE...VIS
COULD EASILY DROP TO 1-2SM WITH SOME DENSE FOG POSSIBLE. CMS
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH FOR CIG TRENDS...MEDIUM FOR TIMING AND SPECIFIC HEIGHTS.
* MEDIUM FOR LIGHT RAIN OR DRIZZLE OVERNIGHT/SATURDAY MORNING.
* HIGH FOR WINDS THRU THE PERIOD...MEDIUM FOR TIMING CHANGES. CMS
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...MVFR CIGS WITH BREEZY NW WINDS.
SUNDAY...VFR.
MONDAY...SCHC -SHSN. MVFR PSBL. N TO NE WINDS.
TUESDAY...VFR. GUSTY NW WINDS.
WEDNESDAY AND THURSDAY...VFR. BREEZY SW WINDS AT TIMES.
KMD
&&
.MARINE...
324 PM CST
A TROUGH OF LOW PRESSURE MOVING ACROSS THE REGION IS HELPING TO
PROVIDE SIGNIFICANT DIFFERENCES WITH WIND SPEED AND DIRECTION
ACROSS THE ENTIRE LAKE THIS AFTERNOON...AND EXPECT THESE
DIFFERENCES TO REMAIN IN PLACE TONIGHT INTO SATURDAY MORNING.
WHILE SOUTHERLY FLOW REMAINS IN PLACE OVER THE SOUTHERN HALF OF
THE LAKE...SOUTHERLY WINDS OVER THE NORTHERN HALF ARE ALREADY
SLOWLY BECOMING MORE NORTHERLY AS THIS TROUGH MOVES ACROSS THE
LAKE. THIS TREND WILL CONTINUE OVER THE NORTHERN HALF TONIGHT WITH
MORE NORTHERLY WINDS EXPECTED LATER TONIGHT...WHILE SOUTHERLY
WINDS PERSIST OVER THE SOUTHERN HALF. NEW LOW PRESSURE WILL THEN
DEVELOP ALONG THIS TROUGH/BOUNDARY EARLY SATURDAY MORNING AND MOVE
ACROSS THE LAKE SATURDAY. EXPECT SPEEDS TO INCREASE DURING THE DAY
AS WINDS BECOME MORE WESTERLY IN THE AFTERNOON...AND THEN
NORTHWEST IN THE EVENING. EXPECT SPEEDS TO THEN DIMINISH SATURDAY
NIGHT INTO SUNDAY AS THIS LOW DEPARTS AND HIGH PRESSURE BUILDS
ACROSS THE REGION.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ744-LMZ745...10 AM SATURDAY TO 4 AM
SUNDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743...10 AM
SATURDAY TO 10 PM SATURDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
238 PM CST FRI DEC 26 2014
.SHORT TERM...
238 PM CST
THROUGH SUNDAY...
AN UPPER LEVEL RIDGE AXIS STRETCHES FROM CUBA UP THE ATLANTIC COAST
WITH THE SURFACE HIGH OVER THE SOUTHEAST U.S. THE UPPER LEVEL RIDGE
SHIFTS VERY LITTLE THROUGH SATURDAY. A NARROW SURFACE TROUGH EXTENDS
FROM TEXAS THROUGH THE UPPER PENINSULA OF MICHIGAN THIS AFTERNOON. A
CLOSED LOW WILL FORM OVER THE MID MISSISSIPPI VALLEY TONIGHT AND
MOVE OVER NORTHERN IL LATE TONIGHT/EARLY SATURDAY MORNING BEFORE
MAKING IT TO QUEBEC SATURDAY EVENING. WEAK HIGH PRESSURE THEN
SPREADS OVER THE CWA SUNDAY.
TEMPERATURES CONTINUE TO CLIMB INTO THE UPPER 40S TO LOWER 50S THIS
AFTERNOON WITH THE MAJORITY OF THE CWA RECEIVING AMPLE SUNSHINE.
CLOUD COVER WILL INCREASE THIS EVENING AND OVERNIGHT AS THE LOW
TAKES SHAPE AND MOVES IN. WITH THE SURFACE LOW PASSING RIGHT
OVERHEAD...THINKING FOG OR DRIZZLE IS PROBABLE ESPECIALLY WEST OF A
MCHENRY TO JOLIET LINE. ONLY HAVE PATCHY FOG IN THE FORECAST...BUT
COULD SEE VSBYS IN SOME AREAS DROP TO AROUND OR LESS THAN ONE MILE
DUE TO FOG OR DRIZZLE.
RAIN/DRIZZLE MOVES IN FROM SOUTHWEST TO NORTHEAST LATE THIS
EVENING...AND LATEST RAP AND HRRR GUIDANCE INDICATE THE PRECIP WILL
MOVE IN QUICKER THAN PREVIOUSLY THOUGHT. IT LOOKS LIKE A GOOD HIGH
POP/LOW QPF SITUATION. HAVE AN INCREASING POP TREND FROM MIDNIGHT
THROUGH THE EARLY MORNING HOURS AS THE LOW MOVES OVERHEAD. LIGHT
RAIN SHIFTS EAST SATURDAY AFTERNOON AS THE LOW CONTINUES NORTHEAST.
GUSTY WEST WINDS ARE EXPECTED TOMORROW WITH GUSTS AROUND 30 MPH IN
THE AFTERNOON. TEMPERATURES WILL ALSO BE FALLING FROM THE LATE
MORNING HOURS ON BEHIND THE LOWS COLD FRONT. HOWEVER AREAS ALONG AND
EAST OF I-55 WILL SEE HIGH TEMPS IN THE MID 40S TO AROUND 50. TEMPS
FALL INTO THE 20S SATURDAY NIGHT.
LIGHT WINDS SHIFT TO OUT OF THE NORTHWEST OR NORTH SUNDAY WITH DRY
CONDITIONS EXPECTED. THE COOLER AIRMASS WILL KEEP HIGH TEMPS IN THE
30S...BUT WE SHOULD SEE SOME SUNSHINE.
JEE
&&
.LONG TERM...
238 PM CST
SUNDAY NIGHT THROUGH FRIDAY...
AN UPPER LEVEL LOW WILL SHIFT EAST OVER NORTHERN QUEBEC
SUNDAY...AND A VORTICITY STREAMER ASSOCIATED WITH THE LOW PUSHES
SOUTH THROUGH THE REGION MONDAY. ANOTHER TROUGH AXIS SWINGS THROUGH
WEDNESDAY. AT THE SURFACE...WEAK HIGH PRESSURE REMAINS OVER THE
REGION SUNDAY NIGHT. A COLD FRONT COINCIDED WITH THE VORT STREAMER
PUSHES THROUGH THE REGION MONDAY. ARCTIC HIGH PRESSURE FOLLOWS THE
COLD FRONT...AND FINALLY SHIFTS SOUTH TO THE GULF STATES THURSDAY.
CLOUDS INCREASE SUNDAY NIGHT AHEAD OF THE COLD FRONT WITH LOW TEMPS
IN THE 20S. FLURRIES AND LIGHT SNOW ARE EXPECTED ALONG THE COLD
FRONT AS MODELS CONTINUE TO FEATURE A LITTLE QPF. COLD AIR MASSES
SUCH AS THIS ONE CAN USUALLY SQUEEZE OUT ANY MOISTURE LINGERING IN
THE AIR SO HAVE HIGHER POPS WHERE MODELS FEATURED QPF AND FLURRIES
ACROSS THE REST OF THE CWA. NOT EXPECTING MUCH SNOW ACCUMULATION IF
ANY AT ALL. NORTH WINDS DOWN THE LAKE MAY RESULT IN LAKE EFFECT
SNOW OVER NW INDIANA MONDAY NIGHT INTO TUESDAY. COULD SEE A COUPLE
TENTHS OF AN INCH OF SNOW.
THE BIGGER IMPACT WILL BE TEMPERATURES. HIGH TEMPS WILL BE IN THE
LOWER 30S MONDAY THEN ONLY IN THE UPPER TEENS TO MID 20S TUESDAY.
LOW TEMPS TUESDAY WILL BE VARY FROM THE SINGLE DIGITS OVER NORTH
CENTRAL IL TO AROUND 10 DEGREES OVER NORTHWEST INDIANA. BRISK NW
WINDS WILL CREATE BELOW ZERO WINDCHILLS TUESDAY NIGHT INTO WEDNESDAY
MORNING. THE WHOLE CWA FEELS THE CHILL WEDNESDAY WITH HIGH TEMPS
AROUND 20 DEGREES BUT GUSTY WEST WINDS WILL MAKE IT FEEL LIKE IT IS
IN THE SINGLE DIGITS.
THE CENTER OF THE HIGH SHIFTS SOUTH OF THE REGION THURSDAY ALLOWING
TEMPS TO WARM SLIGHTLY INTO THE UPPER 20S THURSDAY. LONG RANGE
GUIDANCE THEN FEATURES A LOW PRESSURE SYSTEM MOVING UP THE OHIO
RIVER VALLEY LATE NEXT WEEK. GUIDANCE HAS THE SYSTEM BRINGING US
SNOW OVER THE WEEKEND...SO WILL KEEP AN EYE ON THIS SYSTEM.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* MVFR CIGS DEVELOPING THIS EVENING AND LOWERING TO IFR OVERNIGHT.
* CHANCE OF LIGHT RAIN OR DRIZZLE OVERNIGHT INTO SATURDAY MORNING.
* GUSTY SOUTH/SOUTHWEST WINDS THIS AFTERNOON.
* STRONG/GUSTY WESTERLY WINDS LATE SATURDAY MORNING INTO SATURDAY
AFTERNOON. CMS
//DISCUSSION...UPDATED 18Z...
A WEAK FRONTAL BOUNDARY EXTENDS FROM NORTHEAST WISCONSIN SOUTHWEST
INTO THE PLAINS. AS THIS BOUNDARY SLOWLY MOVES EAST TODAY...NEW
LOW PRESSURE WILL DEVELOP OVER MISSOURI AND LIFT NORTHEAST ACROSS
NORTHWEST ILLINOIS SATURDAY MORNING AND THEN CONTINUE NORTHEAST
ACROSS LAKE MICHIGAN SATURDAY AFTERNOON. SOUTHERLY WINDS WILL
CONTINUE TODAY AND TONIGHT AHEAD OF THIS LOW WITH SOME GUSTS INTO
THE UPPER TEEN/LOWER 20KT RANGE POSSIBLE THIS AFTERNOON. WINDS
WILL SHIFT TO THE WEST AS THE LOW DEPARTS AND QUICKLY INCREASE
LATE SATURDAY MORNING INTO SATURDAY AFTERNOON...WHEN THERE COULD
BE A FEW HOUR PERIOD OF GUSTS TO 30 KT...BEFORE RELAXING BACK
INTO THE MID 20KT RANGE THROUGH SUNSET SATURDAY EVENING.
CIGS RANGING FROM 2KFT TO 4KFT ARE SPREADING NORTH INTO SOUTHERN
MISSOURI AND SOUTHERN ILLINOIS LATE THIS MORNING. THIS CLOUD COVER
IS EXPECTED TO CONTINUE NORTH ACROSS THE TERMINALS LATE THIS
AFTERNOON INTO THIS EVENING THEN SLOWLY LOWER...EVENTUALLY INTO
IFR OVERNIGHT. OVERALL CONFIDENCE IN THIS TREND IS HIGH BUT THE
TIMING AND SPECIFIC CIGS WILL LIKELY REQUIRE TWEAKS WITH LATER
FORECASTS. AS THE LOW APPROACHES...ITS POSSIBLE THAT CIGS COULD
LOWER INTO LIFR...ESPECIALLY AT RFD. CIGS WILL THEN LIFT INTO MVFR
AS THE LOW DEPARTS AND POSSIBLY BECOME VFR SATURDAY AFTERNOON.
CONFIDENCE REGARDING PRECIP OVERNIGHT INTO SATURDAY MORNING IS
SOMEWHAT LOW. PRECIP AMOUNTS LOOK FAIRLY LIGHT BUT COULD BE A
PERIOD OF VERY LIGHT RAIN OR DRIZZLE. OPTED TO MAINTAIN CURRENT
RAIN/DRIZZLE MENTION FOR NOW. VISIBILITIES WILL ALSO LIKELY LOWER
INTO MVFR AS LOW LEVEL MOISTURE INCREASES AND IF DRIZZLE BECOMES
PREVAILING...IN ADDITION TO THE APPROACHING LOW PRESSURE...VIS
COULD EASILY DROP TO 1-2SM WITH SOME DENSE FOG POSSIBLE. CMS
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH FOR CIG TRENDS...MEDIUM FOR TIMING AND SPECIFIC HEIGHTS.
* MEDIUM FOR LIGHT RAIN OR DRIZZLE OVERNIGHT/SATURDAY MORNING.
* HIGH FOR WINDS THRU THE PERIOD...MEDIUM FOR TIMING CHANGES. CMS
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...MVFR CIGS WITH BREEZY NW WINDS.
SUNDAY...VFR.
MONDAY...SCHC -SHSN. MVFR PSBL. N TO NE WINDS.
TUESDAY...VFR. GUSTY NW WINDS.
WEDNESDAY AND THURSDAY...VFR. BREEZY SW WINDS AT TIMES.
KMD
&&
.MARINE...
234 AM CST
HIGH PRESSURE OVER THE SOUTHEAST STRETCHING UP THE ATLANTIC SEABOARD
WILL REMAIN STATIONARY TODAY BEFORE SHIFTING OUT OVER THE ATLANTIC
ON SATURDAY. MEANWHILE A LOW PRESSURE TROUGH AXIS EXTENDS FROM THE
SOUTHERN HIGH PLAINS THROUGH WESTERN WISCONSIN. THE TROUGH AXIS WILL
SHIFT OVER THE NORTHERN HALF OF THE LAKE TODAY WHICH WILL EASE THE
CURRENT GRADIENT OVER THE LAKE THAT IS DRIVING SOME STRONGER
SOUTHERLIES...ESPECIALLY OVER THE SOUTHERN HALF OF THE
LAKE...WHERE WINDS TO 30 KT CAN BE EXPECTED THROUGH MID MORNING. A
SECONDARY LOW MOVING THROUGH THE TROUGH AXIS WILL REACH CENTRAL
LAKE MICHIGAN AFTER DAYBREAK SATURDAY THEN NORTHEAST OF LAKE
HURON SATURDAY NIGHT...DEEPENING AS IT DOES SO. MODEST HIGH
PRESSURE EMERGES BEHIND THIS SYSTEM...BUT WILL DRIVE A PERIOD OF
WESTERLY WINDS TO 30 KT WITH A MODIFIED COLD FRONT. STRONGER HIGH
PRESSURE WILL MOVE OUT OF CANADA BEYOND THIS TIME FRAME...BRINGING
COLDER NORTH- NORTHWESTERLY FLOW OVER THE LAKE WHICH MAY BECOME
GUSTY AT TIMES. BEFORE THE HIGH MOVES INTO THE NORTHERN PLAINS...A
WEAK TROUGH AND COLD FRONT WILL PASS OVER THE LAKE BY
MONDAY...FOLLOWED BY ANOTHER WEAK TROUGH MID-WEEK.
KMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ744-LMZ745...10 AM SATURDAY TO 4 AM
SUNDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743...10 AM
SATURDAY TO 10 PM SATURDAY.
&&
$$
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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS DODGE CITY KS
335 PM CST FRI DEC 26 2014
...UPDATE TO LONG TERM...
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 258 PM CST FRI DEC 26 2014
THE NAM MODEL SEEMED TO OUTPERFORM THE HRRR WITH RESPECT TO
PLACEMENT LATE THIS MORNING AND EARLY AFTERNOON. THE MODEL WILL
CONTINUE TO BE USED AS A GUIDE IN COMBINATION WITH CURRENT TRENDS TO
PLACE POPS AND QPF/SNOW AMOUNTS FOR THE REST AFTERNOON/EVENING. A
DECISION WILL NEED TO BE MADE WHETHER TO EXTEND EITHER IN TIME AND
AREAL COVERAGE OR DROP THE ADVISORY ALTOGETHER AT 4 PM. AT THIS
TIME, EXTENSION DOES NOT APPEAR TO BE LIKELY. THE NAM INDICATED AN
INTSENSIFICATION OF FRONTOGENESIS IN THE MID TO LATE AFTERNOON,
HOWEVER IT IS ASSOCIATED WITH NON FAVORABLE AGEOSTROPHIC FLOW FOR
VERTICAL MOTION. ONCE THE SNOW BEGINS TO WIND DOWN FROM THE
DISSIPATION OF VERTICAL MOTION, CLOUD CEILING HEIGHTS WILL BEGIN
TO INCREASE FROM WEST TO EAST THIS EVENING. FOG SHOULD NOT BE A
BIG CONCERN HEADING INTO THE OVERNIGHT AS SURFACE BOUNDARY LAYER
AIR SEES A BUMP IN DEW POINT TEMPERATURES (WHICH THE NAM SEEMS TO
REFLECT), AS SURFACE WINDS WILL BE WELL ENOUGH MIXED AND SLIGHTLY
DOWNSLOPED.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 327 PM CST FRI DEC 26 2014
MEDIUM RANGE MODELS INDICATE A POSITIVELY TILTED UPPER LEVEL TROUGH
OF LOW PRESSURE SHIFTING EASTWARD OUT OF THE DESERT SOUTHWEST INTO
THE SOUTH PLAINS SUNDAY BRINGING ABOUT A WESTERLY FLOW ALOFT TO THE
WESTERN HIGH PLAINS. A WEAKENING FLOW ALOFT COMBINED WITH A LACK OF
LOW/MID LEVEL MOISTURE WILL RESULT IN DRY CONDITIONS PREVAILING
ACROSS WESTERN KANSAS THROUGH LATE MONDAY MORNING. PRECIP CHANCES
WILL INCREASE A LITTLE MONDAY AFTERNOON AS DEEPENING UPPER LEVEL
TROUGH DROPS SOUTHWARD ACROSS THE PACIFIC NORTHWEST SETTING UP A
DIFLUENT FLOW ALOFT ACROSS THE WESTERN HIGH PLAINS. THIS WILL
CONINCIDE WITH ANOTHER STRONG COLD FRONT PUSHING SOUTHWARD ACROSS
WESTERN KANSAS AS THE FLOW ALOFT STRENGTHENS AFTER EXITING THE
TROUGH AXIS OUT WEST. AS A RESULT, SNOW IS LIKELY TO DEVELOP
ACROSS THE HIGH PLAINS OF COLORADO MONDAY WITH THE POTENTIAL FOR
SNOW SPREADING EASTWARD INTO PORTIONS OF WESTERN KANSAS FROM
MONDAY AFTERNOON THROUGH EARLY TUESDAY MORNING. ALTHOUGH IT IS TOO
EARLY TO DETERMINE SNOW AMOUNT POTENTIAL, WEAK QPF SIGNALS SUGGEST
LIGHTER AMOUNTS, IF ANY.
ALTHOUGH REBOUNDING SOMEWHAT, TEMPERATURES WILL REMAIN BELOW NORMAL
SUNDAY WITH COLDER AIR SLOW TO ERODE AS A LEE SIDE TROUGH OF LOW
PRESSURE DEVELOPS ACROSS EASTERN COLORADO. THE GFS/ECMWF SHOW THE
H85 0C ISOTHERM BEGINNING TO EDGE BACK TO THE NORTH BUT REMAINING
WELL SOUTH OF CENTRAL AND MUCH OF SOUTHWEST KANSAS. EVEN WITH
DECREASED CLOUD COVER EXPECTED, LOOK FOR HIGHS ONLY UP INTO THE
30S(F) SUNDAY AFTERNOON WITH NEAR 40F STILL A POSSIBILITY CLOSER TO
THE OKLAHOMA BORDER. THE GFS AND ECMWF CONTINUE TO PROJECT A
STRONG ARCTIC COLD FRONT PUSHING THROUGH WESTERN KANSAS MONDAY
BRINGING ANOTHER ROUND OF COLD AIR SURGING SOUTHWARD INTO THE
REGION EARLY NEXT WEEK. HIGHS COULD BE AS LOW AS THE TEENS(F)
TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1257 PM CST FRI DEC 26 2014
A BRIEF PERIOD OF -FZDZ OR MIX OF FZDZ/SN WILL OCCUR BEFORE
CONDITIONS ALOFT ARE COLD AND SATURATED ENOUGH TO PRODUCE CLOUD
SEEDING AND ALL SNOW PRECIPITATION TYPE. TAF MAY NEED OPT BE AMENDED
TO FOLLOW THIS TREND THIS AFTERNOON. CEILINGS WILL DROP TO AROUND
500 FEET DURING THE BRIEF SNOW EPISODE THROUGH THIS AFTERNOON MAINLY
AT ALL THE TERMINALS BEFORE INCREASING AGAIN TO AROUND 1000 FT OR
GREATER ONCE THE SNOW EPISODE ENDS THIS EVENING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 18 32 16 38 / 20 0 0 0
GCK 14 31 15 36 / 30 0 0 0
EHA 13 32 16 39 / 20 0 0 0
LBL 17 34 15 39 / 20 0 0 0
HYS 16 29 15 36 / 60 0 0 0
P28 21 38 18 41 / 20 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RUSSELL
LONG TERM...JJOHNSON
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
307 PM CST FRI DEC 26 2014
...UPDATED SHORT TERM...
.SYNOPSIS...
ISSUED AT 258 PM CST FRI DEC 26 2014
A BAND OF SNOW DEVELOPED EAST OF HUGOTON AND ULYSSES EXTENDING
NORTH THROUGH THE GARDEN CITY AREA AND JUST EAST OF SCOTT CITY
THOUGH LANE COUNTY LATE THIS MORNING AND EARLY THIS AFTERNOON.
PRECEDING THIS AREA OF ENHANCED FRONTOGENETIC FORCING IN THE
DENDRITIC GROWTH ZONE WAS A PERIOD OF VERY LIGHT FREEZING DRIZZLE
WITH GENERALLY LITTLE IMPACT ITSELF. BEST DUAL POL RADAR HOURLY
ESTIMATES CAME FROM NORTHERN FINNEY COUNTY AND SCOTT/LANE
COUNTIES, SUGGESTING HE BEST RATES OCCURRED IN THOSE AREAS THIS
AFTERNOON. HIGHWAY 83 NORTH FROM GARDEN CITY WAS COMPLETELY SNOW
COVERED. MOST RECENT CALLS TO THE TIGHTEN AREA INDICATED ONLY
UNDER AN INCH OF SNOW.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 258 PM CST FRI DEC 26 2014
THE NAM MODEL SEEMED TO OUTPERFORM THE HRRR WITH RESPECT TO
PLACEMENT LATE THIS MORNING AND EARLY AFTERNOON. THE MODEL WILL
CONTINUE TO BE USED AS A GUIDE IN COMBINATION WITH CURRENT TRENDS TO
PLACE POPS AND QPF/SNOW AMOUNTS FOR THE REST AFTERNOON/EVENING. A
DECISION WILL NEED TO BE MADE WHETHER TO EXTEND EITHER IN TIME AND
AREAL COVERAGE OR DROP THE ADVISORY ALTOGETHER AT 4 PM. AT THIS
TIME, EXTENSION DOES NOT APPEAR TO BE LIKELY. THE NAM INDICATED AN
INTSENSIFICATION OF FRONTOGENESIS IN THE MID TO LATE AFTERNOON,
HOWEVER IT IS ASSOCIATED WITH NON FAVORABLE AGEOSTROPHIC FLOW FOR
VERTICAL MOTION. ONCE THE SNOW BEGINS TO WIND DOWN FROM THE
DISSIPATION OF VERTICAL MOTION, CLOUD CEILING HEIGHTS WILL BEGIN
TO INCREASE FROM WEST TO EAST THIS EVENING. FOG SHOULD NOT BE A
BIG CONCERN HEADING INTO THE OVERNIGHT AS SURFACE BOUNDARY LAYER
AIR SEES A BUMP IN DEW POINT TEMPERATURES (WHICH THE NAM SEEMS TO
REFLECT), AS SURFACE WINDS WILL BE WELL ENOUGH MIXED AND SLIGHTLY
DOWNSLOPED.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 154 AM CST FRI DEC 26 2014
THE UPPER LEVEL TROUGH WILL SHIFT EASTWARD ACROSS THE PLAINS
DURING THE WEEKEND WITH A RIDGE OF HIGH PRESSURE BUILDING ACROSS
THE EASTERN PACIFIC. MID LEVELS OF THE ATMOSPHERE LOOK TO BE
FAIRLY DRY DURING THIS TIME PERIOD LEADING TO MOSTLY CLEAR SKIES
OVER WESTERN KANSAS. PRECIPITATION CHANCES THEN INCREASE EARLY
NEXT WEEK AS AN UPPER LEVEL TROUGH DIGS SOUTH ACROSS THE WESTERN
UNITED STATES AND SET UP A DIFLUENT FLOW ALOFT OVER THE THE HIGH
PLAINS. THIS FEATURE WILL ALSO HELP PUSH DOWN ANOTHER ARCTIC
AIRMASS AT THE SURFACE WITH BELOW NORMAL TEMPERATURES EXPECTED
THROUGH MID WEEK. TEMPERATURES LOOK TO BE COLD ENOUGH FOR ANY
PRECIPITATION THAT FALLS TO BE IN THE FORM OF SNOW. THE
AFOREMENTIONED UPPER LEVEL TROUGH INTENSIFIES AND BECOMES A LOW
ACROSS THE DESERT SOUTHWEST MID WEEK THEN EJECTS EASTWARD TOWARDS
THE PLAINS BY THE END OF THE WEEK. PARTLY CLOUDY SKIES AND DRY
CONDITIONS ARE EXPECTED AS THIS FEATURE APPROACHES WITH ANOTHER
CHANCE OF SNOW LATE IN THE WEEK AS THIS SYSTEM TREKS ACROSS THE
PLAINS. AS FOR TEMPERATURES, HIGHS THIS WEEKEND LOOK TO REACH INTO
THE 30S WITH LOWS IN THE UPPER TEENS AND LOWER 20S. HIGHS MONDAY
LOOK TO RANGE FROM AROUND 20 DEGREES ACROSS WEST CENTRAL KANSAS TO
MID 30S ACROSS SOUTH CENTRAL KANSAS. THIS IS DUE TO THE COLD FRONT
MOVING THROUGH THE AREA IN THE AFTERNOON. HIGHS IN THE TEENS ARE
THEN ANTICIPATED TUESDAY WITH LOWS DIPPING INTO THE SINGLE DIGITS
AND POSSIBLY EVEN BELOW ZERO ACROSS WEST CENTRAL KANSAS BY SUNRISE
WEDNESDAY. TEMPERATURES THEN SLOWLY REBOUND TO THE 30S BY FRIDAY
WITH LOWS INCREASING INTO THE TEENS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1257 PM CST FRI DEC 26 2014
A BRIEF PERIOD OF -FZDZ OR MIX OF FZDZ/SN WILL OCCUR BEFORE
CONDITIONS ALOFT ARE COLD AND SATURATED ENOUGH TO PRODUCE CLOUD
SEEDING AND ALL SNOW PRECIPITATION TYPE. TAF MAY NEED OPT BE AMENDED
TO FOLLOW THIS TREND THIS AFTERNOON. CEILINGS WILL DROP TO AROUND
500 FEET DURING THE BRIEF SNOW EPISODE THROUGH THIS AFTERNOON MAINLY
AT ALL THE TERMINALS BEFORE INCREASING AGAIN TO AROUND 1000 FT OR
GREATER ONCE THE SNOW EPISODE ENDS THIS EVENING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 18 32 16 38 / 30 0 0 0
GCK 14 31 15 36 / 40 0 0 0
EHA 13 32 16 39 / 30 0 0 0
LBL 17 34 15 39 / 30 0 0 0
HYS 16 29 15 36 / 90 0 0 0
P28 21 38 18 41 / 30 10 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 4 PM CST /3 PM MST/ THIS AFTERNOON
FOR KSZ043-044-061>063-074-075-084.
&&
$$
SYNOPSIS...RUSSELL
SHORT TERM...RUSSELL
LONG TERM...HOVORKA_42
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
518 PM EST FRI DEC 26 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 330 PM EST FRI DEC 26 2014
ONE MORE UNSEASONABLY MILD DAY IS IN STORE FOR SATURDAY AS A LOW
PRESSURE SYSTEM OVER MISSOURI TRACKS NORTHEAST THROUGH WISCONSIN AND
NORTHERN MICHIGAN.
MOISTURE STREAMING NORTH AHEAD OF THIS SYSTEM WILL BRING CLOUDS AND
OCCASIONAL LIGHT RAIN OR DRIZZLE BEGINNING LATE TONIGHT AND
CONTINUING THROUGH SATURDAY. THE RAIN MAY MIX WITH A LITTLE LIGHT
SNOW SATURDAY NIGHT BEFORE ENDING AS A COLD FRONT PASSES THROUGH.
WE WILL SEE SOME CHILLY AIR AND LIGHT LAKE EFFECT SNOW SHOWERS
ARRIVE THIS WEEK WITH HIGHS MAINLY IN THE 20S. NO SIGNIFICANT SNOW
ACCUMULATIONS ARE EXPECTED AT THIS TIME.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 330 PM EST FRI DEC 26 2014
NO MAJOR CHANGES IN THINKING TO THE GOING FORECAST. WIDESPREAD LOW
CLOUDS DEVELOP LATER THIS EVENING AS SFC DEW POINTS AROUND 40 STREAM
IN FROM THE SOUTHWEST. LATEST RUNS OF THE HRRR SHOW SCATTERED LIGHT
CONVECTIVE LOOKING RAIN SHOWERS DEVELOPING THIS EVENING ACROSS
MISSOURI AND ILLINOIS. THESE SHOULD WILL LIKELY TRACK INTO THE AREA
FROM THE SOUTHWEST OR DEVELOP OVERHEAD OVERNIGHT AND PERSIST
SATURDAY WITHIN THE WARM ADVECTION ZONE AHEAD OF THE APPROACHING SFC
LOW AND COLD FRONT. IN ADDITION TO THE CONVECTIVE RAIN SHOWERS...
SOME PATCHY DRIZZLE MAY BE SQUEEZED OUT OF THE LOW CLOUDS AT TIMES
LATE TONIGHT AND SATURDAY.
DEEPER MOISTURE MOVES EAST OF THE AREA AFTER 00Z SUNDAY ABOUT THE
TIME THE COLDER AIR IS ARRIVING. PRECIPITATION BEHIND THE SFC COLD
FRONT SHOULD TREND TOWARD JUST SOME VERY LIGHT MIXED RAIN AND SNOW
SHOWERS. NO SNOW ACCUMULATIONS EXPECTED LATE SATURDAY NIGHT INTO
EARLY SUNDAY DUE TO VERY SHALLOW MOISTURE PROFILES AND QUESTIONABLE
DGZ SATURATION. ADDITIONALLY...SURFACE RIDGING/ANTICYCLONIC FLOW IS
QUICK TO BUILD IN WHICH ACTUALLY LEADS TO DECENT PROSPECT FOR
SUNSHINE DEVELOPING SUNDAY AFTERNOON.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 330 PM EST FRI DEC 26 2014
WE CONTINUE TO EXPECT A TREND TOWARD COLDER WEATHER IN THE LONG TERM
WITH CHCS OF SNOW SHOWERS THROUGH THE PERIOD. SNOW ACCUMULATIONS DO
NOT LOOK TO BE ANYTHING SIGNIFICANT IN THE FCST PERIOD FOR NOW. WE
WILL CONTINUE TO MONITOR THIS POTENTIAL AS IT WOULD NOT TAKE MAJOR
CHANGES TO BRING A BETTER POTENTIAL OF LAKE EFFECT.
THE CHC OF SNOW FOR SW LOWER ON MON DOES NOT LOOK REAL GOOD AT THIS
TIME. A SHORT WAVE TROUGH WILL BE MOVING INTO THE GREAT LAKES REGION
FROM THE WNW ON MON. HOWEVER A STRONG 1050+ MB RIDGE TO OUR WEST
WILL BE IN CONTROL OF THE LOWER LEVELS HERE. NE FLOW AND AN
EXTENSION OF THE SFC RIDGE IN PLACE WILL LIMIT PCPN POTENTIAL.
THE PERIOD FROM TUE THROUGH THU THEN WILL FEATURE THE COLDEST TEMPS
OF THE LONG TERM. THE MON SHORT WAVE WILL COMPLETE THE TRANSITION OF
THE UPPER AIR PATTERN TO MORE OF A NW FLOW ALOFT OVER THE AREA.
COLDER AIR WILL CONTINUE TO FILTER IN ON THE NRLY AND EVENTUALLY NW
LOW LEVEL FLOW. THE AIR WILL BE PLENTY COLD ENOUGH FOR LAKE
EFFECT...HOWEVER WE WILL REMAIN ON THE SOUTH SIDE OF THE NRN BRANCH
OF THE JET. SHORT WAVES DIVING SE ARE EXPECTED TO REMAIN JUST NORTH
OF THE CWFA. THIS WILL LIMIT MOISTURE DEPTH SIGNIFICANTLY AND ALSO
THE DEEP LAYER INSTABILITY.
LAKE EFFECT COULD BE MORE ROBUST IF THE UPPER JET AND THE ASSOCIATED
SHORT WAVES ARE ABLE TO DIVE JUST A LITTLE FURTHER SOUTH. WE BELIEVE
THAT THE STRONG CUTOFF UPPER LOW ACROSS THE SW U.S. AND THE RIDGE
AHEAD OF IT WILL HOLD THE NRN BRANCH OF THE JET JUST NORTH OF THE
AREA.
WE COULD SEE THE INITIAL EFFECTS OF THE CUTOFF UPPER LOW START TO
MOVE IN AS EARLY AS NEXT FRI AS WARM AND MOISTURE ADVECTION AHEAD OF
IT STARTS TO OVERRUN THE COLDER AIR EXPECTED TO BE IN PLACE. THE
MODELS TYPICALLY EJECT THESE SYSTEMS OUT TOO QUICK...SO WE WILL KEEP
THE CHC OF PCPN LOW AT THIS TIME FOR NEXT FRI.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 518 PM EST FRI DEC 26 2014
ONCE AGAIN WARM AIR SURGING NORTHWARD WILL BRING IFR CONDITIONS TO
ALL OF THE TAF SITES MOST OF THE DAY TIME HOURS OF SATURDAY. THE
CLOUDS ARE ALREADY DEVELOPING NEAR SOUTH BEND AND ARE EXPANDING
NORTHWARD. BY 03Z ALL TAF SITES SHOULD HAVE MVFR CIGS....BY 12Z
IFR CIGS.
&&
.MARINE...
ISSUED AT 330 PM EST FRI DEC 26 2014
THE PRESSURE GRADIENT RELAXES TONIGHT SO WINDS AND WAVES ARE
EXPECTED TO SUBSIDE. HOWEVER THEY WILL RAMP UP AGAIN LATE SATURDAY
AND SATURDAY NIGHT AS A COLD FRONT PASSES ACROSS LK MI.
&&
.HYDROLOGY...
ISSUED AT 330 PM EST FRI DEC 26 2014
HAVE CANCELED THE ADVISORY FOR THE MAPLE RIVER AT MAPLE RAPIDS AS
LATEST FORECAST HAS IT CRESTING A HALF FOOT BELOW BANKFULL SUNDAY.
SYCAMORE CREEK AT HOLT CRESTED LAST NIGHT AND IS FALLING BELOW
BANKFULL AT THIS TIME. ABOUT A TENTH OF AN INCH OF PRECIPITATION IS
EXPECTED ON SATURDAY WHICH WILL NOT AFFECT THE RIVERS MUCH. A LACK
OF SIGNIFICANT PRECIPITATION INTO THE NEW YEAR WILL ALLOW THE LARGER
RIVERS TIME TO CREST AND FALL WITHOUT MUCH IMPACT.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR LMZ844>849.
&&
$$
SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...NJJ
AVIATION...WDM
HYDROLOGY...CAS
MARINE...MEADE
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
330 PM EST FRI DEC 26 2014
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/HYDRO/MARINE
.SYNOPSIS...
ISSUED AT 330 PM EST FRI DEC 26 2014
ONE MORE UNSEASONABLY MILD DAY IS IN STORE FOR SATURDAY AS A LOW
PRESSURE SYSTEM OVER MISSOURI TRACKS NORTHEAST THROUGH WISCONSIN AND
NORTHERN MICHIGAN.
MOISTURE STREAMING NORTH AHEAD OF THIS SYSTEM WILL BRING CLOUDS AND
OCCASIONAL LIGHT RAIN OR DRIZZLE BEGINNING LATE TONIGHT AND
CONTINUING THROUGH SATURDAY. THE RAIN MAY MIX WITH A LITTLE LIGHT
SNOW SATURDAY NIGHT BEFORE ENDING AS A COLD FRONT PASSES THROUGH.
WE WILL SEE SOME CHILLY AIR AND LIGHT LAKE EFFECT SNOW SHOWERS
ARRIVE THIS WEEK WITH HIGHS MAINLY IN THE 20S. NO SIGNIFICANT SNOW
ACCUMULATIONS ARE EXPECTED AT THIS TIME.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 330 PM EST FRI DEC 26 2014
NO MAJOR CHANGES IN THINKING TO THE GOING FORECAST. WIDESPREAD LOW
CLOUDS DEVELOP LATER THIS EVENING AS SFC DEW POINTS AROUND 40 STREAM
IN FROM THE SOUTHWEST. LATEST RUNS OF THE HRRR SHOW SCATTERED LIGHT
CONVECTIVE LOOKING RAIN SHOWERS DEVELOPING THIS EVENING ACROSS
MISSOURI AND ILLINOIS. THESE SHOULD WILL LIKELY TRACK INTO THE AREA
FROM THE SOUTHWEST OR DEVELOP OVERHEAD OVERNIGHT AND PERSIST
SATURDAY WITHIN THE WARM ADVECTION ZONE AHEAD OF THE APPROACHING SFC
LOW AND COLD FRONT. IN ADDITION TO THE CONVECTIVE RAIN SHOWERS...
SOME PATCHY DRIZZLE MAY BE SQUEEZED OUT OF THE LOW CLOUDS AT TIMES
LATE TONIGHT AND SATURDAY.
DEEPER MOISTURE MOVES EAST OF THE AREA AFTER 00Z SUNDAY ABOUT THE
TIME THE COLDER AIR IS ARRIVING. PRECIPITATION BEHIND THE SFC COLD
FRONT SHOULD TREND TOWARD JUST SOME VERY LIGHT MIXED RAIN AND SNOW
SHOWERS. NO SNOW ACCUMULATIONS EXPECTED LATE SATURDAY NIGHT INTO
EARLY SUNDAY DUE TO VERY SHALLOW MOISTURE PROFILES AND QUESTIONABLE
DGZ SATURATION. ADDITIONALLY...SURFACE RIDGING/ANTICYCLONIC FLOW IS
QUICK TO BUILD IN WHICH ACTUALLY LEADS TO DECENT PROSPECT FOR
SUNSHINE DEVELOPING SUNDAY AFTERNOON.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 330 PM EST FRI DEC 26 2014
WE CONTINUE TO EXPECT A TREND TOWARD COLDER WEATHER IN THE LONG TERM
WITH CHCS OF SNOW SHOWERS THROUGH THE PERIOD. SNOW ACCUMULATIONS DO
NOT LOOK TO BE ANYTHING SIGNIFICANT IN THE FCST PERIOD FOR NOW. WE
WILL CONTINUE TO MONITOR THIS POTENTIAL AS IT WOULD NOT TAKE MAJOR
CHANGES TO BRING A BETTER POTENTIAL OF LAKE EFFECT.
THE CHC OF SNOW FOR SW LOWER ON MON DOES NOT LOOK REAL GOOD AT THIS
TIME. A SHORT WAVE TROUGH WILL BE MOVING INTO THE GREAT LAKES REGION
FROM THE WNW ON MON. HOWEVER A STRONG 1050+ MB RIDGE TO OUR WEST
WILL BE IN CONTROL OF THE LOWER LEVELS HERE. NE FLOW AND AN
EXTENSION OF THE SFC RIDGE IN PLACE WILL LIMIT PCPN POTENTIAL.
THE PERIOD FROM TUE THROUGH THU THEN WILL FEATURE THE COLDEST TEMPS
OF THE LONG TERM. THE MON SHORT WAVE WILL COMPLETE THE TRANSITION OF
THE UPPER AIR PATTERN TO MORE OF A NW FLOW ALOFT OVER THE AREA.
COLDER AIR WILL CONTINUE TO FILTER IN ON THE NRLY AND EVENTUALLY NW
LOW LEVEL FLOW. THE AIR WILL BE PLENTY COLD ENOUGH FOR LAKE
EFFECT...HOWEVER WE WILL REMAIN ON THE SOUTH SIDE OF THE NRN BRANCH
OF THE JET. SHORT WAVES DIVING SE ARE EXPECTED TO REMAIN JUST NORTH
OF THE CWFA. THIS WILL LIMIT MOISTURE DEPTH SIGNIFICANTLY AND ALSO
THE DEEP LAYER INSTABILITY.
LAKE EFFECT COULD BE MORE ROBUST IF THE UPPER JET AND THE ASSOCIATED
SHORT WAVES ARE ABLE TO DIVE JUST A LITTLE FURTHER SOUTH. WE BELIEVE
THAT THE STRONG CUTOFF UPPER LOW ACROSS THE SW U.S. AND THE RIDGE
AHEAD OF IT WILL HOLD THE NRN BRANCH OF THE JET JUST NORTH OF THE
AREA.
WE COULD SEE THE INITIAL EFFECTS OF THE CUTOFF UPPER LOW START TO
MOVE IN AS EARLY AS NEXT FRI AS WARM AND MOISTURE ADVECTION AHEAD OF
IT STARTS TO OVERRUN THE COLDER AIR EXPECTED TO BE IN PLACE. THE
MODELS TYPICALLY EJECT THESE SYSTEMS OUT TOO QUICK...SO WE WILL KEEP
THE CHC OF PCPN LOW AT THIS TIME FOR NEXT FRI.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1233 PM EST FRI DEC 26 2014
AREA OF LOW CLOUDS CONTINUES TO PLAGUE THE N/NW PORTION OF THE
AREA EARLY THIS AFTERNOON...AFFECTING ONLY KMKG AT THIS TIME. SOME
ADDITIONAL CU IS FORMING JUST SOUTH OF THIS CLOUD COVER THAT WILL
AFFECT KGRR MORE THAN ANY OTHER LOCATION. WE EXPECT THE CLOUD
COVER TO HOLD IN AT KMKG EXCEPT FOR A FEW BREAKS AT TIMES. THE
CLOUD COVER WILL EXPAND ACROSS ALL AREAS TONIGHT AS THE NEXT
SYSTEM APPROACHES THE AREA FROM THE SW.
SHOWERS WILL BECOME POSSIBLE AFTER 08-09Z ACROSS THE WEST. THEY
WILL THEN EXPAND TO THE EAST THEREAFTER. CIGS WILL LOWER AND WILL
LIKELY END UP IFR FOR THE DAYLIGHT HOURS ON SAT AND CONTINUE
THROUGH THE END OF THIS FCST PERIOD. VSBYS ARE NOT EXPECTED TO BE
TOO BAD...MAINLY IN THE MVFR CATEGORY.
&&
.MARINE...
ISSUED AT 330 PM EST FRI DEC 26 2014
THE PRESSURE GRADIENT RELAXES TONIGHT SO WINDS AND WAVES ARE
EXPECTED TO SUBSIDE. HOWEVER THEY WILL RAMP UP AGAIN LATE SATURDAY
AND SATURDAY NIGHT AS A COLD FRONT PASSES ACROSS LK MI.
&&
.HYDROLOGY...
ISSUED AT 330 PM EST FRI DEC 26 2014
HAVE CANCELED THE ADVISORY FOR THE MAPLE RIVER AT MAPLE RAPIDS AS
LATEST FORECAST HAS IT CRESTING A HALF FOOT BELOW BANKFULL SUNDAY.
SYCAMORE CREEK AT HOLT CRESTED LAST NIGHT AND IS FALLING BELOW
BANKFULL AT THIS TIME. ABOUT A TENTH OF AN INCH OF PRECIPITATION IS
EXPECTED ON SATURDAY WHICH WILL NOT AFFECT THE RIVERS MUCH. A LACK
OF SIGNIFICANT PRECIPITATION INTO THE NEW YEAR WILL ALLOW THE LARGER
RIVERS TIME TO CREST AND FALL WITHOUT MUCH IMPACT.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR
LMZ844>849.
&&
$$
SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...NJJ
AVIATION...NJJ
HYDROLOGY...CAS
MARINE...MEADE
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1237 PM CST FRI DEC 26 2014
.UPDATE...
ISSUED AT 1142 AM CST FRI DEC 26 2014
UPDATED TO INCLUDE 18Z AVIATION DISCUSSION BELOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 340 AM CST FRI DEC 26 2014
MAIN ITEM OF CONCERN IN THE SHORT TERM IS WHAT IS LOOKING
INCREASING LIKELY TO BE A 3 TO 5 INCH BAND OF SNOW TONIGHT FROM
SW/SC MN INTO WC WI. IS SOME CONCERN THAT A NARROW STRIP WITHIN
THIS BAND COULD SEE TOTALS MORE IN THE 5-7 INCH RANGE. GIVEN THE
THREAT OF NEAR WARNING TYPE SNOW TOTALS ALONG WITH MODERATE TO
HIGH CONFIDENCE IN THE BAND OF 3 TO 5 INCHES OF SNOW
OCCURRING...WE DECIDED TO HOIST A WINTER WEATHER ADVY FOR TONIGHT
FOR ABOUT THE SE HALF OF THE MPX CWA.
WATER VAPOR IMAGERY SHOWS TWO FEATURES OF INTEREST IN THE SHORT
TERM. A CLOSED LOW DOWN IN THE 4 CORNERS REGION AND A NRN STREAM
SHORTWAVE WORKING SOUTHEAST INTO NRN MONTANA. THESE TWO FEATURES
WILL PHASE OVER THE PLAINS TONIGHT. THE 4 CORNERS WAVE WILL BE THE
DOMINATE PLAYER FOR PRECIP...THOUGH IT WILL BE LOSING ITS
AMPLIFICATION AS IT MERGES WITH THE NRN STREAM WAVE. AS THE
PREVIOUS LONG TERM DISCUSSION WENT OVER...CONVERGENCE BETWEEN
THESE TWO WAVES TONIGHT WILL RESULT IN A PRETTY SHARP GRADIENT ON
THE NW SIDE OF THE SNOW BAND...WITH AREAS NW OF A GRANITE FALLS TO
LITTLE FALLS LINE LIKELY SEEING NOTHING TONIGHT.
AT THE SFC...THERE IS A LEE SIDE LOW OVER ERN NEW MEXICO...WITH A
STATIONARY BOUNDARY EXTENDING ACROSS THE TX PANHANDLE UP INTO THE
SE TIP OF MN AND THE WRN U.P. OF MICHIGAN. ALSO OF IMPORTANCE
THIS MORNING IS THAT WE ARE ACTUALLY SEEING COLD AIR SPILLING
SOUTH BEHIND THIS BOUNDARY...WITH MOST LOCATION IN SASKATCHEWAN
CURRENTLY BELOW ZERO F. AS THE 4 CORNERS WAVE EJECTS NE...MODELS
ARE IN GOOD AGREEMENT IN A 1015 MB OR LOWER SFC LOW DEVELOPING
OVER NRN MO TONIGHT THAT WILL HEAD OFF INTO THE STRAITS OF
MACKINAC BY SAT AFTERNOON. THIS LOW WILL BE PULLING IN THE POLAR
AIR ACROSS SRN CANADA...WHICH WILL ALLOW FOR A HEALTHY DEFORMATION
BAND OF SNOW TO DEVELOP TO THE NW OF THE SFC LOW...WHICH WILL BE
AIDED BY A TROWAL THAT WILL BE WORKING IN ON THE COOL SIDE OF A
100+KT SWRLY MID LEVEL JET STREAK THAT WILL BE WORKING ACROSS ERN
IOWA TONIGHT.
FAVORED THIS FORECAST CLOSELY TO THE 26.00 GFS. WHEN COMPARING QPF
SWATHS OF VARIOUS PIECES OF GUIDANCE THROUGH 00Z TO THE
RAP...THE GFS QPF WAS PRETTY MUCH LAID DOWN RIGHT ON TOP OF WHAT
THE RAP HAS...SO FELT CONFIDENT IN RIDING THAT FORECAST FORWARD.
CONFIDENCE IN THIS COURSE WAS FURTHER BOOSTED BY THE 26.06
NAM...WHICH SHIFTED A BIT SE FROM ITS 26.00 RUN TO MORE OR LESS
FALL IN LINE WITH THE 26.00 GFS. THE GFS SHOWS THE TROP FOLD
GETTING DOWN BELOW 450 MB...SO THIS WILL HELP FORCE A RATHER
INTENSE DEFORMATION BAND OF PRECIP JUST TO THE NW OF ITS PATH. QPF
FROM THE GFS GETS UP INTO THE 0.3-0.35 RANGE...BUT THE NAM12 ALONG
WITH OTHER HIGHER RES MODELS SHOW STORM TOTAL QPFS CLIMBING OVER
0.4. FOR SNOW RATIOS...ROEBBER RATIO PROBABILITIES FOR TONIGHT
WERE SPLIT PRETTY EVENLY BETWEEN THE AVERAGE AND LIGHT
BINS...WHICH WOULD SUPPORT RATIOS BEING UP IN THE 14-15:1 RANGE.
0.3" OF QPF WITH THESE RATIOS WOULD PUSH SNOW TOTALS UP TO A
LITTLE OVER 4 INCHES...BUT IF WE SEE QPF UP CLOSER TO 0.45 LIKE
THE NAM HAS...THEN YOU ARE TALKING ABOUT SNOW TOTALS MORE IN THE
BALLPARK OF 6". LOOKING AT BUFR SOUNDINGS...LAPSE RATES ATOP THE
H8-H7 FGEN LAYER ARE UP AROUND 7 DEG C PER KM...SO WE SHOULD SEE A
WEAKLY STABLE ENVIRONMENT ATOP THE FGEN...WHICH WOULD FAVOR THE
DEVELOPMENT OF SOME CSI TYPE BANDING...AND SUPPORT THE HIGHER QPF
AMOUNTS THE HI-RES MODELS ARE HINTING AT. CURRENT EXPECTATIONS ARE
FOR A BAND OF 3+" TO FALL BETWEEN PLYMOUTH TO THE NORTH AND
ROCHESTER TO THE SOUTH WITH THE POTENTIAL FOR NOT MUCH MORE THAN A
20-30 MILE WIDE BAND OF 5-7" TO FALL WITHIN THIS BAND. AT THE
MOMENT...THE HIGHEST LIKELIHOOD FOR TOTALS LIKE THAT LOOKS TO
CENTERED NEAR A ST. JAMES/RED WING/CHIP FALLS LINE.
FOR THE REST OF THE FORECAST...TEMPERATURES WILL REMAIN STEADY
THROUGH THE DAY TODAY AS CLOUD COVER AND WEAK CAA HELP KEEP TEMPS
PARKED AT WHERE THEY CURRENTLY ARE UNTIL THE SFC LOW GETS GOING
OVER MO TONIGHT...WHICH WILL FINALLY HELP PULL COLDER AIR THIS
DIRECTION. WINDS WILL ALSO BE REMAINING OUT OF THE NORTH...BUT
SPEEDS WILL REMAIN UNDER 15MPH...SO NOT WORRIED ABOUT THERE BEING
BLOWING AND DRIFTING ISSUES WITH TONIGHTS SNOW.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 340 AM CST FRI DEC 26 2014
THE MOST NOTABLE WEATHER OVER THE NEXT WEEK BLEEDS INTO THE
BEGINNING OF THE LONG TERM FORECAST PERIOD...AND THEN BENIGN BUT
COLDER WEATHER MARKS THE REMAINDER OF THE FORECAST.
SNOW WILL BE ONGOING AT THE START OF THE PERIOD SATURDAY
MORNING...ALTHOUGH IT SHOULD TAPER OFF RATHER EFFICIENTLY FROM
WEST TO EAST ON SATURDAY MORNING AS DRIER AIR ASSOCIATED WITH THE
INCOMING SURFACE RIDGE WORKS INTO THE REGION. AN ADDITIONAL
DUSTING /MN/ TO ONE INCH /WI/ APPEARS POSSIBLE AFTER DAYBREAK
SATURDAY...BRINGING STORM TOTAL AMOUNTS TO THE GENERAL 2 TO 5 INCH
RANGE IN THE ADVISORY AREA.
TEMPERATURES OVER THE WEEKEND WON/T STRAY TOO FAR FROM NORMAL
VALUES FOR LATE DECEMBER...WITH HIGHS MAINLY IN THE 20S.
BY MONDAY...HOWEVER...H85 TEMPS DECLINE TO AROUND -18C...AND EVEN
FURTHER FOR TUESDAY...TO AROUND -20C. THIS WILL TRANSLATE TO
HIGHS IN THE SINGLE DIGITS /F/ AREA-WIDE BY TUESDAY...WITH SUB-
ZERO LOWS. WITH WINDS STAYING UP IN THE 5-10KT RANGE MONDAY AND
TUESDAY NIGHTS...WIND CHILLS WILL NEED TO BE MONITORED FOR THE
POTENTIAL FOR AN ADVISORY...PARTICULARLY OVER WEST CENTRAL MN
WHERE READINGS ARE FORECAST TO DIP NEAR 25 BELOW.
THE BAROCLINIC ZONE TIGHTENS JUST SOUTH OF THE FORECAST AREA ON
MONDAY. COULD SEE SOME RESULTANT LIGHT SNOW AS FAR NORTH AS
SOUTHERN MINNESOTA. HAVE INCLUDED SLIGHT CHANCE POPS ALONG THE
INTERSTATE 90 CORRIDOR FOR MONDAY...WHERE UP TO ONE INCH APPEARS
POSSIBLE.
TEMPERATURES MODERATE SLIGHTLY DURING THE MIDDLE OF THE UPCOMING
WEEK...WITH HIGHS IN THE 20S BY THURSDAY. HOWEVER...AN ARCTIC
FRONT IS FORECAST TO PUSH ACROSS THE AREA BY FRIDAY...CAUSING
TEMPERATURES TO RETREAT BACK BELOW NORMAL. THIS CLIPPER-LIKE
SYSTEM MAY BRING ACCUMULATING SNOW TO THE AREA LATE NEXT WEEK.
HAVE INCLUDED 20 POPS FOR THURSDAY...BUT TEMPORAL AND SPATIAL
AGREEMENT BETWEEN THE MODELS IS ADMITTEDLY NOT GREAT AT THIS
POINT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1142 AM CST FRI DEC 26 2014
ALL SITES EXPECTED TO LINGER IN THE LOWER-END MVFR RANGE FOR
CEILINGS THRU THIS AFTN THEN DROP INTO IFR RANGE THIS EVENING THRU
OVERNIGHT. BEST CHCS FOR -SN WILL BE ALONG AND EAST OF A KRWF-KMSP
LINE...SO THOSE TWO SITES PLUS THE TWO WI SITES ARE EXPCTED TO SEE
-SN DEVELOP SHORTLY AFTER 00Z...STARTING OUT WITH MVFR VSBY BUT
THEN DROPPING INTO IFR RANGE SHORTLY THEREAFTER FOR GENERALLY 4-6
HOURS. CONDS IMPROVE BEYOND 12Z TMRW MRNG. HAVE ONLY GONE DOWN TO
1SM FOR VSBY BUT GOING DOWN TO 1/2SM OR LOWER...ESP FOR KMSP-KRNH-
KEAU...CERTAINLY CANNOT BE RULED OUT. SAME AS HAVING CEILINGS /OR
VV/ DROPPING TO 500FT OR LOWER AT TIMES. WINDS WILL REMAIN
GENERALLY NLY THROUGHOUT THIS TAF SET...THEN BECOME MORE WNW BY
MIDDAY TMRW.
KMSP...CEILINGS TO REMAIN SUB-1700FT FOR THE START OF THE 26/18Z
TAF...BUT THERE IS A WINDOW OF TIME CEILINGS MAY NUDGE ABOVE THAT
LEVEL TO CLOSE TO 2 KFT. HOWEVER...AS -SN MOVES IN THIS EVENING...
CEILINGS DROP BACK DOWN AND MAY WELL HIT IFR LEVELS BY MIDNIGHT.
LITTLE TRICKY TO SEE HOW LONG THE IFR-VSBY -SN WILL LAST BUT HAVE
OPTED TO KEEP THE 6-HOURS-WORTH OF IFR CONDS ATTM. CONDS IMPROVE
AROUND DAYBREAK WITH MID-UPR RANGE MVFR CEILINGS VERY POSSIBLE SAT
AFTN.
/OUTLOOK FOR KMSP/
SUN...VFR...CHC MVFR CIGS. WINDS S 5 KTS...BCMG E.
MON...VFR. WINDS N 10 KTS.
TUE...VFR. WINDS NW 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 9 AM CST
SATURDAY FOR MNZ053-060>063-065>070-073>078-082>085-091>093.
WI...WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO NOON CST
SATURDAY FOR WIZ014>016-023>028.
&&
$$
UPDATE...JPC
SHORT TERM...MPG
LONG TERM...LS
AVIATION...JPC
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
339 PM CST Fri Dec 26 2014
.SHORT TERM: (Through Sunday Night)
Issued at 329 PM CST Fri Dec 26 2014
Low pressure will develop along the cold front currently over
northwest Missouri in response to shortwave trough ejecting out of
the base of mean trough over the western CONUS tonight. This low
will move northeast into the Great Lakes by tomorrow at the same
time that the shortwave moves into the the Upper Midwest. NAM and
GFS show that the cold front will enter the northwest part of the
CWA late tonight and exit the CWA by tomorrow afternoon. While
precipitation is currently limited on radar over the central CONUS,
expect rain chances to increase rapidly this evening as low level
moisture convergence increases ahead of shortwave trough. Latest
runs of the HRRR as well as the NSSL-WRF have depicted rain
developing throughout the evening hours with it becoming more
concentrated over southeast Missouri into southern Illinois after
midnight. Have continued going forecast trend of increasing
chance PoPs through the evening hours and with likely PoPs over
the southeast half of the CWA after midnight. Then concentrated
likely PoPs tomorrow morning over the southeast half of the CWA
when the GFS depicts increasing mid level frontogenesis associated
with the shortwave trough. Kept a chance of rain or snow going
over the far southeast part of the CWA tomorrow evening before
drier air and subsidence works into the area on Saturday evening.
Sunday and Sunday evening still looks dry at this point.
Kept with falling temperatures will frontal passage tomorrow.
Otherwise MOS guidance are in decent agreement and looks
reasonable.
Britt
.LONG TERM: (Monday through Next Friday)
Issued at 329 PM CST Fri Dec 26 2014
There is relatively good agreement in the global models in that a
positively tilted mean trough will stay established through at
least the first half of next week from central Canada into the
western CONUS. This will keep a relatively fast zonal flow over
MO/IL through most of the period. A large area of surface high
pressure will move under the zonal flow with no real notable
shortwaves troughs that would offer any precipitation chances at
least through Thursday. Model discrepancies show up by Friday as
the operational GFS is faster than it`s own ensemble mean in
ejecting the main upper low out of the southwest toward the
Midwest. While this is faster than the rest of the models, even
the ECMWF is showing precipitation developing over the area in a
broad warm air advection regime ahead of it bringing the upper low
through the area on Saturday. So with this said will go ahead and
introduce snow with some rain to the forecast on Friday.
Cold front will pass through the area on Monday and temperatures
will fall below normal on Tuesday and Wednesday before returning to
near normal for the start of a new year late in the week.
Britt
&&
.AVIATION: (For the 18z TAFs through 18z Saturday Afternoon)
Issued at 1203 PM CST Fri Dec 26 2014
MVFR SC deck over far southern Missouri to slowly develop and
slide north this afternoon as low level moisture is on the
increase ahead of next weather system. But movement/development is
a bit slower than originally thought, so backed off at taf sites
til early this evening. Otherwise, winds to remain from the south
til frontal passage which will be between 12z-15z Saturday, then winds
to veer to the west around 15kts. Precipitation will be limited
with it mainly occurring with frontal passage, except over
central, northeast MO, west central IL. Kept mention of light rain
for KCOU after 03z Saturday and around 06z for KUIN. Cigs to lower
but remain low end mvfr with frontal passage.
Specifics for KSTL:
MVFR SC deck over far southern Missouri to slowly develop and
slide north this afternoon as low level moisture is on the
increase ahead of next weather system. But movement/development is
a bit slower than originally thought, so backed off at KSTL til
after 00z Saturday. Otherwise, winds to remain from the south til frontal
passage which will be around 15z Saturday, then winds to veer to
the west around 15kts. Precipitation will be limited with it mainly
occurring with frontal passage. Cigs to lower but remain low end
mvfr with frontal passage.
Byrd
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1130 AM CST FRI DEC 26 2014
.UPDATE...
ISSUED AT 715 AM CST FRI DEC 26 2014
THE SNOW HAS ENDED ACROSS WESTERN NEBRASKA. THE WINTER WEATHER
ADVISORY HAS BEEN CANCELLED IN THIS AREA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 358 AM CST FRI DEC 26 2014
SATELLITE AND THE RUC INDICATE A CLOSED H500 MB LOW MOVING ACROSS
THE FOUR CORNERS. A DEFORMATION BAND OF SNOW EXTENDED FROM NRN
COLO INTO WY WHICH WAS SHOWING SIGNS OF WEAKENING. A NEW
DEFORMATION BAND WAS DEVELOPING ACROSS NRN NM AND THIS DISTURBANCE
IS FCST BY THE MODELS TO LIFT THROUGH THE FCST AREA TODAY AND
TONIGHT AFFECTING AREAS ALONG AND EAST OF A LINE FROM KIML-KOGA-
KTIF-KONL. THE MODEL CONSENSUS SUGGESTS THE BEST SNOWFALL...4 TO 6
INCHES...WOULD LIFT FROM HAYES CENTER TO NORTH PLATTE AND THEN
NORTHEAST THROUGH BURWELL AND ONEILL. ROCK AND HOLT COUNTY HAVE
BEEN ADDED TO THE WINTER WEATHER ADVISORY IN EFFECT UNTIL 06Z
TONIGHT.
THE MODEL QPF IS MOST TIGHTLY CLUSTERED OVER NORTH PLATTE AND MODEL
QPF SPREAD INCREASES EAST AND WEST OF THAT POINT. WE ARE EXPECTING
AROUND 0.25 TO 0.33 INCHES OF QPF FROM THIS DISTURBANCE. THE GFS WAS
THE FIRST MODEL TWO DAYS AGO TO INDICATE A SEMI CLOSED H700MB LOW
LIFTING NORTHEAST THROUGH THE FCST AREA. THE OTHER MODELS CARRIED
THIS DISTURBANCE EAST MOSTLY THROUGH KS AND SCNTL/ERN NEB. NOW ALL
THE MODELS ARE IN AGREEMENT LIFTING THIS LOW THROUGH THE FCST AREA.
THERE IS SOME WOBBLING GOING ON WHICH IS NORMAL. THE RAP IS A BIT
EAST OF THE MODEL CONSENSUS. BUT GIVEN THE PERFORMANCE OF THE MODELS
YESTERDAY FAVORING THE CNTL PANHANDLE VS THE RAP WITH THE CHEYENNE
DIVIDE...THE MODEL CONSENSUS WINS THE FCST. GIVEN THE MODEL
CONSENSUS AND A 15 TO 1 RATIO...4 TO 6 INCHES OF SNOW APPEARS
LIKELY. THE 06Z NAM CONTINUES TO INDICATE THESE AMOUNTS FROM
KIML-KLBF-KBUB-KONL BUT SHOWS 6 TO 8 INCHES FROM KBBW-KBUB-KONL.
THIS IS A TREND IN THE MODELS FOR SLOWER DEVELOPMENT AND THE NAM
ACTUALLY HAS A CLOSED H700MB LOW OVER KGRI AT 03Z THIS EVENING WHILE
THE MODEL CONSENSUS WAS SHOWS THIS LOW AS AN OPEN WAVE. IF THIS
TREND CONTINUES AND A CLOSED H700MB LOW WERE TO TRAVERSE THE FCST
AREA...THE CHANCE OF HEAVY SNOW WOULD INCREASE.
FOR NOW THE FCST IS FOR 3 TO 6 INCHES OF SNOW IN THE ADVISORY AREA.
THIS IS AN INCREASE OF 2 INCHES OVER THE PREVIOUS FORECAST.
PATCHY FREEZING DRIZZLE CONTINUES THIS MORNING ASSOCIATED WITH
TRAPPED MOISTURE BELOW A 700MB DRY INTRUSION. THIS DRIZZLE IS
EXPECTED TO CLEAR THE FCST AREA 12Z-15Z THIS MORNING AND A CHECK OF
THE NEDOR WEBSITE INDICATES ROADS IN CUSTER COUNTY ARE COMPLETELY
COVERED WITH ICE...UNTREATED AND NO TRAVEL IS ADVISED SO THE
ADVISORY WILL BEGIN EARLIER IN THIS AREA. WITH QUICKLY CHANGING
AND DETERIORATING CONDITIONS...WILL ADD ADDITIONAL COUNTIES TO THE
ADVISORY TO THE NORTHEAST AND ISSUE A FREEZING RAIN ADVISORY FOR
FAR NORTH CENTRAL NEBRASKA THROUGH THIS MORNING.
THE MODELS INDICATE DRY AIR WILL WORK EAST TO HIGHWAY 83 AFTER
MIDNIGHT ALLOWING FOR A FEW TO SEVERAL HOURS OF MODEST RADIATIONAL
COOLING. LOWS TONIGHT ALONG AND WEST OF HIGHWAY 83 SHOULD FALL TO
NEAR OR BELOW ZERO IN MANY AREAS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 358 AM CST FRI DEC 26 2014
PRIMARY FORECAST CONCERNS FOR THIS PERIOD DEALS WITH TEMPERATURES
AS A COLDER AIRMASS STAYS IN PLACE ACROSS THE REGION...THEN WITH
AN INTRUDING ARCTIC COLD FRONT EARLY NEXT WEEK WHICH BRINGS AN
AIRMASS INTO THE AREA THAT IS COLDER YET ALONG WITH CHANCES FOR
SNOW.
MODELS ARE IN FAIRLY GOOD AGREEMENT WITH THE EVOLUTION OF THE UPPER
LEVEL PATTERN THROUGH THE NEXT WEEK WHICH LEADS TO SLIGHTLY ABOVE
AVERAGE CONFIDENCE IN THE FORECAST. THAT BEING SAID...THERE ARE
DIFFERENCES IN DETAILS OF INDIVIDUAL SHORTWAVE TROUGHS MOVING ACROSS
THE AREA WHICH DOES PROVIDE SOME UNCERTAINTY FOR PORTIONS OF THE
FORECAST.
BY SATURDAY MORNING THE SHORTWAVE TROUGH THAT WILL PUSH UP THROUGH
KANSAS AND EASTERN NEBRASKA WILL BE ON ITS WAY EAST OF THE REGION
WHILE A WEAK SHORTWAVE COMING OUT OF THE NORTHERN STREAM WILL PASS
ACROSS THE FORECAST AREA THROUGH THE DAY SATURDAY. BEHIND THIS
SHORTWAVE SUBSIDENCE WILL BE INCREASING WHICH SHOULD LEAD TO
CLEARING SKIES THROUGH THE DAY. HIGH PRESSURE AT THE SURFACE WILL
DRIFT TO THE SOUTHEAST THROUGH THE DAY AND SATURDAY NIGHT. SO
LOOKING FOR DECREASING WINDS...BUT AS IT WILL BE CENTERED SOUTH AND
EAST OF THE LOCAL AREA THE PRESSURE GRADIENT MAY KEEP WINDS FROM
GOING CALM. EVEN WITH LIGHT WINDS...THE CLEAR SKIES WILL PROMOTE
RADIATIONAL COOLING SATURDAY NIGHT SO COULD GET FAIRLY
COLD...ESPECIALLY IN AREAS WHERE THERE IS FRESH SNOW COVER. MODIFIED
THE PRIOR FORECAST ONLY SLIGHTLY AS IT SEEMED TO HAVE A DECENT
HANDLE ON THE COLDER TEMPERATURES.
WEAK RIDGING BRINGS TEMPERATURES UP SLIGHTLY FOR SUNDAY...BUT WITH
THE AIRMASS REMAINING COLD WITH 850MB TEMPERATURES AT -1C TO -6C
TEMPERATURES WILL LIKELY STAY NEAR OR BELOW FREEZING. THE ONGOING
FORECAST WILL KEEP HIGHS IN THE MID TO UPPER 20S. LOOKING FOR THE
ARCTIC FRONT MENTIONED EARLIER TO START PUSHING INTO NORTHERN
NEBRASKA BY 12Z MONDAY MORNING. THIS IS WHERE SOME DIFFERENCES LIE
THOUGH...MAINLY WITH THE TIMING OF THE SHORTWAVES THROUGH THE AREA.
THE GFS IS A BIT QUICKER TO MOVE THINGS THROUGH AND TOOK A SLOWER
APPROACH WHICH IS SHOWN BY BOTH THE ECMWF AND GEM. THE SYSTEM IN
QUESTION IS CURRENTLY OVER THE NORTHERN PACIFIC...MOVING TOWARDS THE
GULF OF ALASKA. THE MODELS DO AGREE THAT THIS SYSTEM WILL MOVE INTO
THE PACIFIC NORTHWEST SATURDAY NIGHT THE WILL DIG DOWN THE PACIFIC
COAST AND BECOME CLOSED OFF TUESDAY NIGHT INTO WEDNESDAY. AS THIS
OCCURS AN ADDITIONAL SHORTWAVE TROUGH THAT IS CURRENTLY PART OF THE
ORIGINAL SYSTEM WILL GET CAUGHT UP IN THE NORTHERN STREAM AND WILL
MOVE DOWN THROUGH THE NORTHERN AND CENTRAL PLAINS TUESDAY. THE
INITIAL COLD FRONT WILL MOVE ACROSS THE FORECAST AREA MONDAY
MORNING...WHICH DROPS 850MB TEMPERATURES DOWN TO NEAR -15C BY 18Z
MONDAY. THE PRESSURE GRADIENT WILL TIGHTEN BEHIND THE FRONT SO
ANTICIPATING WINDS TO INCREASE FOR MONDAY. THERE WILL ALSO BE A
CHANCE FOR SNOW BEHIND THE FRONT...HOWEVER WITH A GENERAL LACK OF
MOISTURE NOT EXPECTING QPF AMOUNTS TO BE SIGNIFICANT. THE BEST LIFT
IS SEEN ACROSS THE NORTHERN PART OF THE FORECAST AREA SUNDAY
NIGHT...THEN WEAKENS ACROSS THE CENTRAL AND EASTERN PART OF THE
AREA. SO WILL KEEP THE TREND FOR HIGHER PRECIPITATION CHANCES OVER
THE NORTHERN ZONES FOR EARLY MONDAY MORNING THEN TRANSITION TO THE
WESTERN HALF ON MONDAY...THEN TO THE SOUTHERN PART OF THE FORECAST
AREA FOR MONDAY NIGHT. AGAIN...QPF AMOUNTS DON/T LOOK TO BE TOO MUCH
SO AT MOST EXPECT A COUPLE INCHES OF SNOW.
THE BIG PUSH OF COLDER AIR WILL COME WITH THE TUESDAY SHORTWAVE
TROUGH MOVES IN. MODELS AREN/T QUITE AS COLD AS PRIOR RUNS WERE BUT
STILL DROP 850MB TEMPERATURES DOWN TO -20C OR COLDER FOR TUESDAY.
LOOKING AT ENSEMBLE GUIDANCE...ITS COMING INTO BETTER AGREEMENT FROM
YESTERDAYS RUN...AS THE 26.00 RUN FROM THE GFS ENSEMBLE NOW IS ONLY
GIVING A SPREAD OF 10 DEGREES FOR HIGHS RATHER THAN 30 AS WAS SEEN
YESTERDAY. IT DOES STILL LOOK LIKE TUESDAY AND TUESDAY NIGHT WILL BE
THE COLDEST PERIODS OF THE WEEK...HOWEVER THERE IS CONSIDERABLE
DIFFERENCES IN GOING THROUGH THE WEEK IN HOW MUCH AND WHERE THE COLD
AIR WILL BE SO ALTHOUGH HAVE HIGH CONFIDENCE THAT TEMPERATURES WILL
BE COLD...AND BELOW NORMAL...HOW MUCH BELOW NORMAL WILL REMAIN IN
QUESTION AT THIS TIME AND HAVE JUST KEPT THE TEMPERATURE TREND GOING
DOWNWARD IN THE FORECAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1122 AM CST FRI DEC 26 2014
SNOW WILL CONTINUE FOR AREAS ALONG AND EAST OF A KSNY TO KTIF TO
KANW THIS AFTERNOON INTO THIS EVENING. WIDESPREAD MVFR AND LOCAL
IFR CONDITIONS CAN BE EXPECTED IN THESE AREAS. WEST OF THIS
LINE...LITTLE SNOW IS EXPECTED. CONDITIONS SHOULD BEGIN TO IMPROVE
IN ALL AREAS AFTER 06Z SATURDAY.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST /11 PM MST/ TONIGHT
FOR NEZ009-010-025>029-036>038-057>059-069>071.
&&
$$
UPDATE...CDC
SHORT TERM...CDC
LONG TERM...BROOKS
AVIATION...TAYLOR
AREA FORECAST DISCUSSION
NWS TULSA OK
1137 AM CST FRI DEC 26 2014
.DISCUSSION...
THE 18Z TAF DISCUSSION IS INCLUDED BELOW.
&&
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
GRADUALLY DETERIORATING CONDITIONS ARE EXPTD THRU THE PERIOD AS
LOW LVL MOIST RETURN OCCURS AHEAD OF AN APPROACHING STORM SYSTEM.
MVFR CIGS WILL SINK DOWN INTO THE IFR RANGE AND LIGHT RAIN AND/OR
DRIZZLE WILL BECOME MORE PREVALENT TONIGHT. A COLD FRONT WILL
BRING A WIND SHIFT TO THE NORTHWEST BY LATE TONIGHT OR EARLY
SATURDAY MORNING.
LACY
&&
.PREV DISCUSSION... /ISSUED 1004 AM CST FRI DEC 26 2014/
DISCUSSION...
THE LATEST GUIDANCE FROM THE HRRR AND CURRENT OBSERVATIONS SUGGEST
HIGHS NEEDED UPWARD ADJUSTMENT IN SOME PLACES...AS LOW CLOUDS
HAVE BEEN SLOW TO PROGRESS NORTH INTO THE AREA. SOME BREAKS IN THE
CLOUDS ARE SHOWING UP ON SATELLITE...WHICH COULD ALLOW TEMPS TO
SHOOT UP INTO THE 60S IN SOME PLACES. STILL LOOKS LIKE THE BULK OF
ANY PRECIP WILL BE TONIGHT...POSSIBLY AS EARLY AS THIS AFTERNOON
IN THE SOUTH. THE FORECAST REFLECTS THIS AND WILL NOT BE ADJUSTED
AT THIS TIME.
LACY
PREV DISCUSSION... /ISSUED 546 AM CST FRI DEC 26 2014/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
CIGS 3-4K FEET EXPANDING NORTH ACROSS ENTIRE TAF AREA AND
LOWERING TO 15-25 HND FEET. SCATTERED RAIN BREAKING OUT THIS
AFTERNOON BECOMING MORE WIDESPREAD TONIGHT. ISOLATED THUNDER
LATE TONIGHT SOUTHEAST OK NOT EXPECTED TO IMPACT TAF SITES.
PREV DISCUSSION... /ISSUED 351 AM CST FRI DEC 26 2014/
DISCUSSION...
UPPER FLOW IS BACKING ACROSS THE AREA AHEAD OF THE DIGGING SYSTEM
NEAR THE FOUR CORNERS AREA. THE RESULT IS DEEP-LAYER SOUTHERLY
FLOW AND INCREASING MOISTURE. SATELLITE IMAGES SHOW LOW CLOUDS
DEVELOPING BENEATH THE STREAM OF HIGHER CLOUDS. THE COLD FRONT
ACROSS KANSAS IS EXPECTED TO MAKE RATHER SLOW PROGRESS SOUTHEAST
IN THIS SETUP AND WILL LIKELY NOT REACH OSAGE COUNTY UNTIL LATE
AFTERNOON. TEMPERATURES TODAY ARE TRICKY. IF THE CLOUDS THICKEN AS
EXPECTED THEN TEMPS WILL GENERALLY RISE 10 DEGREES OR LESS AND
STAY IN THE 50S. BUT ANY SIGNIFICANT SUN COULD PUSH READINGS
SEVERAL DEGREES HIGHER THAN THE CURRENT FORECAST.
SCATTERED PATCHES OF LIGHT RAIN WILL DEVELOP WITH TIME
TODAY...WITH FAIRLY WIDESPREAD RAIN IN THE AREA TONIGHT AS THE
COLD FRONT PUSHES THROUGH THE REGION. ELEVATED INSTABILITY
DEVELOPS AS FAR NORTH AS EXTREME SOUTHEAST OKLAHOMA TONIGHT AND AN
ISOLATED THUNDERSTORM IS POSSIBLE.
IT WILL BE A RACE BETWEEN THE ENDING PRECIP AND THE ARRIVAL OF
ENOUGH COLD AIR FOR A BRIEF WINTRY MIX. RIGHT NOW IT APPEARS THAT
A LITTLE SLEET OR A LITTLE SNOW COULD MIX WITH RAIN AS IT ENDS IN
FAR NORTHEAST OKLAHOMA VERY LATE TONIGHT OR EARLY ON SATURDAY
MORNING. THE BEST CHANCE OF ANY VERY LIGHT ACCUMULATION WOULD BE
IN FAR NORTHWEST OSAGE COUNTY...BUT GENERALLY NO ACCUMULATION IS
EXPECTED AT THIS TIME.
SEASONABLY COLD WEATHER WILL SETUP BEHIND THE CURRENT SYSTEM AND
PERSIST INTO MID NEXT WEEK.
TOWARD THE END OF NEXT WEEK...AROUND AND JUST AFTER THE FIRST OF
THE YEAR...MODEL GUIDANCE SHOWS A SIGNIFICANT SYSTEM CROSSING THE
MIDDLE OF THE COUNTRY WITH THE STORM TRACK OVER OR NEAR EASTERN
OKLAHOMA AND NORTHWEST ARKANSAS. THE CURRENT DATA SUGGESTS THAT
ENOUGH COULD AIR WILL BE IN PLACE FOR AT LEAST SOME WINTER WEATHER
POTENTIAL WITH THE BEGINNING OF THE PRECIPITATION. THE EVENTUAL
TRACK OF THE SYSTEM WILL DETERMINE HOW MUCH OF THE REGION GETS
INTO THE WARM SECTOR. OVERALL FORECAST CONFIDENCE IS VERY LOW AS
EXPECTED FOR A COMPLEX SYSTEM 7 DAYS AWAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 60 38 42 25 / 30 60 20 0
FSM 59 48 48 30 / 20 60 50 10
MLC 59 41 41 27 / 30 60 40 0
BVO 59 34 41 21 / 20 50 10 0
FYV 54 47 47 25 / 20 60 50 10
BYV 56 47 47 27 / 20 50 50 10
MKO 57 40 42 26 / 20 60 40 0
MIO 58 38 40 24 / 20 60 20 0
F10 56 38 42 25 / 20 50 30 0
HHW 58 48 48 30 / 30 70 40 10
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...30
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1232 PM CST FRI DEC 26 2014
.DISCUSSION...
PLEASE SEE 18Z AVIATION DISCUSSION.
&&
.AVIATION...
ALL TERMINALS TO THE NORTH AND WEST OF HIGHWAY 59 ARE REPORTING
MVFR CIGS WITH THE MVFR CIG LINE CONTINUING TO SLOWLY MOVE
EASTWARD. AT THIS TIME MVFR CIGS ARE LIKELY AT KHOU AFTER 20Z AND
AT KLBX AND KGLZ BETWEEN 01 AND 02Z. THE MODELS ARE IN GOOD
AGREEMENT FOR LIGHT PRECIPITATION THIS AFTERNOON. WITH A STRONG
ON SHORE FLOW IN ADVANCE OF TOMORROW`S COLD FRONT...LIGHT STREAMER
SHOWERS SHOULD CONTINUE.
BIG QUESTION IS HOW LOW CIGS WILL GO OVER NIGHT. NUMERICAL
GUIDANCE IS IN GOOD AGREEMENT FOR PREVAILING IFR/LIFR
CIGS...HOWEVER I AM NOT READY TO BITE ON THIS SOLUTION BECAUSE THE
MODELS OVER FORECASTED IFR/LIFR CONDITIONS THIS MORNING. THERE
SHOULD BE ENOUGH MIXING IN THE LOWER LAYERS TO PREVENT WIDESPREAD
FOG. AT THIS TIME...I ANTICIPATE ENOUGH MIXING TO ONLY PRODUCE
MOSTLY SCATTERED CLOUDS BELOW 1000 FT.
TOMORROW MORNING...IFR CONDITIONS ARE MOST LIKELY RIGHT ALONG THE
COAST WHERE SEA FOG MAY HAVE AN INFLUENCE ON THE FORECAST.
OTHERWISE...THE COLD FRONT SHOULD PASS THROUGH KCLL AT 13Z...KCXO
BEWTEEN 15-18...AND KIAH AROUND 21Z. LIGHT RAIN AND DRIZZLE WILL
BE ASSOCIATED WITH THE FRONT AT INLAND LOCATIONS...HOWEVER
CHANCES FOR SHOWERS AND THUNDERSTORMS WILL IMPROVE AS THE FRONT
APPROACHES THE COAST TOMORROW AFTERNOON. 44
&&
.PREV DISCUSSION... /ISSUED 1029 AM CST FRI DEC 26 2014/
UPDATE...
THE COLD FRONT THAT WILL MAKE ITS WAY INTO SOUTHEAST TEXAS
SATURDAY WAS ANALYZED AS OF 10 AM JUST NORTH OF LUBBOCK STRETCHING
NORTHEAST TOWARDS WICHITA...KS. SCATTERED SHOWERS HAVE OCCURRED
OFF AND ON THIS MORNING COURTESY SOUTHEASTERLY SURFACE WINDS
PROMOTING MOISTURE ADVECTION...WITH ANOTHER AREA OF SHOWERS
MOVING NORTHEAST TOWARDS THE HOUSTON METRO FROM THE GULF. LATEST
HRRR AND RAP RUNS SHOW THIS ACTIVITY CONTINUING INTERMITTENTLY
THROUGHOUT THE DAY AND CURRENT FORECAST HANDLES THIS WELL.
TEMPERATURES WILL BE A BIT TRICKIER WITH CLOUDS THINNING OVER THE
NORTHEASTERN FORECAST AREA...BUT OVERALL TEMPERATURE TRENDS APPEAR
TO BE ON TRACK. NO CHANGES MADE TO ONGOING FORECAST AT THIS TIME.
HUFFMAN
PREV DISCUSSION... /ISSUED 406 AM CST FRI DEC 26 2014/
DISCUSSION...
30-35KT LLVL JET WILL CONTINUE TRANSPORTING GULF MOISTURE BACK
INTO THE REGION. FCST SOUNDINGS SHOW INCREASING SATURATION AS THE
DAY WEARS ON AND WOULD ANTICIPATE SOME STREAMER SHRA IN THIS TYPE
OF PATTERN. SIMILAR SITUATION TONIGHT WITH POSSIBILITY OF
INCREASED COVERAGE OF DRIZZLE/-RA (MAYBE AN EMBEDDED ISO TSTM OR
TWO). IF SFC WINDS ARE ABLE TO LAY DOWN ENOUGH PATCHY SEA FOG
CAN`T BE RULED OUT EITHER. WENT AHEAD AND NUDGED POPS UP A TOUCH
DURING BOTH PERIODS...MAYBE NOT ENOUGH...BUT OVERALL JUST NUISANCE
ACCUMULATIONS.
BETTER SHOT OF RAINFALL EXPECTED ON SAT AS COLD FRONT MOVES INTO
SE TX AND PROVIDES MORE OF A FOCUSING MECHANISM. BOUNDARY SHOULD
BE MOVING THRU CLL AREA MID/LATE MORNING AND OFF THE COAST SAT EVENING.
WE COULD SEE A FEW STRONG STORMS AHEAD OF THE FRONT SHOULD WE GET
ENOUGH INSTABILITY - HOWEVER THAT`S NOT LOOKING TOO PROMISING
ATTM. WILL CONTINUE TO KEEP AN EYE ON THINGS. DID ADVERTISE
FALLING DAYTIME TEMPS BEHIND THE FRONT IN THE HOURLY GRIDS SAT.
UPPER TROF LAGS TO THE WEST AND SW FLOW ALOFT & FAVORABLE JET
POSITION WILL KEEP RAIN CHANCES GOING INTO SUNDAY UNTIL THE TROF
AXIS FINALLY PUSHES OFF TO THE EAST LATER IN THE DAY.
1048MB+ ARCTIC AIRMASS MOVES INTO NORTHERN PLAINS EARLY NEXT WEEK.
LEADING EDGE OF THIS AIRMASS SHOULD BE MAKING ITS WAY SOUTHWARD
AND INTO SE TX AROUND THE 31ST. TRENDED TEMPS TOWARD THE LOWER
END OF GUIDANCE SUGGESTIONS AND SUSPECT WE MIGHT NEED TO LOWER
THEM FURTHER IN THE COMING DAYS IF/WHEN CONFIDENCE INCREASES.
PATTERN ALOFT AGAIN BECOMES SW DURING THIS TIME PERIOD AS S/W DIGS
DOWN WEST COAST WHICH WOULD FAVOR CONTINUING CLOUDS AND INCREASING
POPS POST FROPA JAN 1-2. SEE NOTHING TO INDICATE FROZEN PRECIP
ACROSS SE TX ATTM...JUST COLD RAIN. 47
MARINE...
LOW-LEVEL JET MAKING ITS PRESENCE KNOWN THIS MORNING WITH ELEVATED
WINDS/SEAS PREVAILING OVER THE COASTAL WATERS. THIS TIGHTENED GRAD-
IENT COULD PERSIST THROUGH THE AFTN HRS...BUT IS STILL EXPECTED TO
EASE UP TONIGHT/OVERNIGHT AS THE NEXT COLD FRONT BEGINS TO MOVE IN
(AND ACROSS) SE TX SAT MORNING/AFTN. THIS BOUNDARY SHOULD FINALLY
ENTER THE BAYS/NEARSHORE WATERS SAT EVE. HOWEVER SHORT TERM TRENDS
WITH THE MODELS HINTING THAT THE FRONT COULD BE A BIT SLOWER...AND
ITS PASSAGE INTO THE COASTAL WATERS MAY NOT BE UNTIL LATE SAT NITE
INTO EARLY SUN MORNING. IF THIS VERIFIES SEA FOG A SLIGHTLY BETTER
POSSIBILITY LATE TONIGHT/EARLY SAT MORN. THE CONTINUING WAA ACROSS
THE COOLER SHELF WATERS TO ALLOW FOR FAVORABLE CONDITIONS FOR FOG.
IN THE MEANTIME...WILL BE RAISING/EXTENDING SMALL CRAFT ADVISORIES
FOR OUR NEAR/OFFSHORE COASTAL WATERS THIS MORNING ON THROUGH NOON.
FOR NOW. MODERATE NLY WINDS BEHIND THE FRONT COULD BRIEFLY PRODUCE
SCEC OR MARGINAL SCA CONDITIONS SUN. 41
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 61 63 41 51 37 / 30 60 40 20 0
HOUSTON (IAH) 65 73 47 50 41 / 50 70 40 50 10
GALVESTON (GLS) 66 70 51 51 49 / 40 70 70 60 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 6 PM CST THIS EVENING FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...14
AVIATION/MARINE...44
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1029 AM CST FRI DEC 26 2014
.UPDATE...
THE COLD FRONT THAT WILL MAKE ITS WAY INTO SOUTHEAST TEXAS
SATURDAY WAS ANALYZED AS OF 10 AM JUST NORTH OF LUBBOCK STRETCHING
NORTHEAST TOWARDS WICHITA...KS. SCATTERED SHOWERS HAVE OCCURRED
OFF AND ON THIS MORNING COURTESY SOUTHEASTERLY SURFACE WINDS
PROMOTING MOISTURE ADVECTION...WITH ANOTHER AREA OF SHOWERS
MOVING NORTHEAST TOWARDS THE HOUSTON METRO FROM THE GULF. LATEST
HRRR AND RAP RUNS SHOW THIS ACTIVITY CONTINUING INTERMITTENTLY
THROUGHOUT THE DAY AND CURRENT FORECAST HANDLES THIS WELL.
TEMPERATURES WILL BE A BIT TRICKIER WITH CLOUDS THINNING OVER THE
NORTHEASTERN FORECAST AREA...BUT OVERALL TEMPERATURE TRENDS APPEAR
TO BE ON TRACK. NO CHANGES MADE TO ONGOING FORECAST AT THIS TIME.
HUFFMAN
&&
.PREV DISCUSSION... /ISSUED 406 AM CST FRI DEC 26 2014/
DISCUSSION...
30-35KT LLVL JET WILL CONTINUE TRANSPORTING GULF MOISTURE BACK
INTO THE REGION. FCST SOUNDINGS SHOW INCREASING SATURATION AS THE
DAY WEARS ON AND WOULD ANTICIPATE SOME STREAMER SHRA IN THIS TYPE
OF PATTERN. SIMILAR SITUATION TONIGHT WITH POSSIBILITY OF
INCREASED COVERAGE OF DRIZZLE/-RA (MAYBE AN EMBEDDED ISO TSTM OR
TWO). IF SFC WINDS ARE ABLE TO LAY DOWN ENOUGH PATCHY SEA FOG
CAN`T BE RULED OUT EITHER. WENT AHEAD AND NUDGED POPS UP A TOUCH
DURING BOTH PERIODS...MAYBE NOT ENOUGH...BUT OVERALL JUST NUISANCE
ACCUMULATIONS.
BETTER SHOT OF RAINFALL EXPECTED ON SAT AS COLD FRONT MOVES INTO
SE TX AND PROVIDES MORE OF A FOCUSING MECHANISM. BOUNDARY SHOULD
BE MOVING THRU CLL AREA MID/LATE MORNING AND OFF THE COAST SAT EVENING.
WE COULD SEE A FEW STRONG STORMS AHEAD OF THE FRONT SHOULD WE GET
ENOUGH INSTABILITY - HOWEVER THAT`S NOT LOOKING TOO PROMISING
ATTM. WILL CONTINUE TO KEEP AN EYE ON THINGS. DID ADVERTISE
FALLING DAYTIME TEMPS BEHIND THE FRONT IN THE HOURLY GRIDS SAT.
UPPER TROF LAGS TO THE WEST AND SW FLOW ALOFT & FAVORABLE JET
POSITION WILL KEEP RAIN CHANCES GOING INTO SUNDAY UNTIL THE TROF
AXIS FINALLY PUSHES OFF TO THE EAST LATER IN THE DAY.
1048MB+ ARCTIC AIRMASS MOVES INTO NORTHERN PLAINS EARLY NEXT WEEK.
LEADING EDGE OF THIS AIRMASS SHOULD BE MAKING ITS WAY SOUTHWARD
AND INTO SE TX AROUND THE 31ST. TRENDED TEMPS TOWARD THE LOWER
END OF GUIDANCE SUGGESTIONS AND SUSPECT WE MIGHT NEED TO LOWER
THEM FURTHER IN THE COMING DAYS IF/WHEN CONFIDENCE INCREASES.
PATTERN ALOFT AGAIN BECOMES SW DURING THIS TIME PERIOD AS S/W DIGS
DOWN WEST COAST WHICH WOULD FAVOR CONTINUING CLOUDS AND INCREASING
POPS POST FROPA JAN 1-2. SEE NOTHING TO INDICATE FROZEN PRECIP
ACROSS SE TX ATTM...JUST COLD RAIN. 47
MARINE...
LOW-LEVEL JET MAKING ITS PRESENCE KNOWN THIS MORNING WITH ELEVATED
WINDS/SEAS PREVAILING OVER THE COASTAL WATERS. THIS TIGHTENED GRAD-
IENT COULD PERSIST THROUGH THE AFTN HRS...BUT IS STILL EXPECTED TO
EASE UP TONIGHT/OVERNIGHT AS THE NEXT COLD FRONT BEGINS TO MOVE IN
(AND ACROSS) SE TX SAT MORNING/AFTN. THIS BOUNDARY SHOULD FINALLY
ENTER THE BAYS/NEARSHORE WATERS SAT EVE. HOWEVER SHORT TERM TRENDS
WITH THE MODELS HINTING THAT THE FRONT COULD BE A BIT SLOWER...AND
ITS PASSAGE INTO THE COASTAL WATERS MAY NOT BE UNTIL LATE SAT NITE
INTO EARLY SUN MORNING. IF THIS VERIFIES SEA FOG A SLIGHTLY BETTER
POSSIBILITY LATE TONIGHT/EARLY SAT MORN. THE CONTINUING WAA ACROSS
THE COOLER SHELF WATERS TO ALLOW FOR FAVORABLE CONDITIONS FOR FOG.
IN THE MEANTIME...WILL BE RAISING/EXTENDING SMALL CRAFT ADVISORIES
FOR OUR NEAR/OFFSHORE COASTAL WATERS THIS MORNING ON THROUGH NOON.
FOR NOW. MODERATE NLY WINDS BEHIND THE FRONT COULD BRIEFLY PRODUCE
SCEC OR MARGINAL SCA CONDITIONS SUN. 41
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 71 61 63 41 51 / 40 30 60 40 20
HOUSTON (IAH) 72 65 73 47 50 / 30 50 70 40 50
GALVESTON (GLS) 70 66 70 51 51 / 30 40 70 70 60
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 6 PM CST THIS EVENING FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT OUT 20 NM.
&&
$$