Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/01/14
AREA FORECAST DISCUSSION
NWS MIAMI FL
1038 AM EST MON DEC 30 2013
.UPDATE...
NO SIGNIFICANT CHANGES TO THE SHORT TERM FORECAST. REGIONAL
OBSERVATIONS AND SATELLITE IMAGERY CONTINUES TO INDICATE LOW
STRATUS AND MOSTLY CLOUDY CONDITIONS ACROSS THE REGION WITH
ISOLATED SHOWERS MAINLY OBSERVED ACROSS THE OFF SHORE ATLANTIC
WATERS. CURRENT GUIDANCE INDICATES ABUNDANT LOW LEVEL MOISTURE AND
MOSTLY CLOUDY SKIES CONTINUING TONIGHT INTO TUESDAY AS THE FRONTAL
BOUNDARY STALLS ACROSS THE REGION...WITH PERIODS OF LOW STRATUS
ALSO CONTINUING TONIGHT INTO TUESDAY. PERIODIC ISOLATED SHOWERS
ARE ALSO POSSIBLE THROUGH THIS PERIOD AND INDICATED IN THE
FORECAST.
60
&&
.PREV DISCUSSION... /ISSUED 630 AM EST MON DEC 30 2013/
AVIATION...
A SLOW MOVING BOUNDARY, STILL JUST TO THE NORTH OF LAKE
OKEECHOBEE, WILL CONTINUE TO BRING A MID DECK OF CLOUDS TO SOUTH
FLORIDA TODAY. THERE WILL ALSO BE SOME LINGERING FOG AND LOW CIGS
FOR THE FIRST COUPLE OF HOURS AFTER SUNRISE. OTHERWISE, EXPECTING
MVFR TO VFR CONDITIONS. THERE IS ALSO A SLIGHT CHANCE OF SOME
RAIN SHOWERS THROUGH THE TAF PERIOD, NOT INCLUDED IN THE TAFS DUE
TO THE PROBABLE LIGHT NATURE OF THE SHOWERS. WINDS WILL BE VARIABLE FOR A
GOOD PART OF THE DAY AS WELL. THEY DO SEEM TO FAVOR THE NORTHEAST
LATER TONIGHT.
PREV DISCUSSION... /ISSUED 306 AM EST MON DEC 30 2013/
SHORT TERM (TODAY-WEDNESDAY)...
A LARGE SCALE MID/UPPER LEVEL TROUGH COVERS MOST OF EASTERN NORTH
AMERICA AT THIS TIME WITH A WEAKENING COLD FRONT NEAR OR JUST
SOUTH OF LAKE OKEECHOBEE EARLY THIS MORNING. THIS FRONT WILL ONLY
SAG VERY SLOWLY SOUTH AND STALL ACROSS EXTREME SOUTH FLORIDA LATER
TODAY. THIS IS DUE TO THE FACT THAT THE SUBTROPICAL RIDGE WILL
REMAIN ANCHORED ACROSS THE CARIBBEAN AND EXTEND NORTHEAST OVER
EASTERN CUBA AND INTO THE CENTRAL ATLANTIC. SOME PATCHY DENSE FOG
AND A LOW STRATUS DECK HAVE DEVELOPED ACROSS MUCH OF SOUTH FLORIDA
THIS MORNING AS A SURFACE BASED INVERSION HAS FORMED ALONG AND
AHEAD OF THE FRONT. EVEN AS THESE CLOUDS MIX OUT SHORTLY AFTER
SUNRISE, ABUNDANT MID LEVEL CLOUDS WILL LINGER WITH THE STALLING
FRONT AND POSSIBLY A FEW SHOWERS. THE NAM IS SUFFERING FROM ITS
TYPICAL MESOSCALE BIAS AND ITS HIGH POPS SEEM WAY OUT OF LINE AND
WENT MUCH CLOSER TO THE GFS AND ECMWF SOLUTIONS. THE HRRR ALSO
WAS NOT SHOWING MUCH SHOWER ACTIVITY THROUGH 16Z ALTHOUGH IT HAS
NOT RUN SINCE 01Z. STRONGER HIGH PRESSURE WILL BUILD OVER THE
SOUTHEAST STATES ON TUESDAY AS THE REMAINS OF AN ARCTIC COLD FRONT
MOVE INTO NORTH FLORIDA AND IT TOO WILL RAPIDLY BECOME DIFFUSE AS
THE RIDGE TO OUR SOUTH MOVES LITTLE. THIS WILL CREATE BREEZY
CONDITIONS ALONG OR NEAR THE ATLANTIC COAST WITH A FEW POSSIBLE
SHOWERS MOVING ONSHORE. BY NEW YEARS` DAY, A MID LEVEL TROUGH THAT
IS CURRENTLY OVER NORTHERN MEXICO WILL LIFT TO THE NORTHEAST INTO
THE SOUTHERN TIER OF STATES GENERATING A SURFACE LOW IN THE GULF
OF MEXICO. THE MODELS HAD BEEN INDICATING THE BAND OF MOISTURE
WOULD LINGER ACROSS SOUTH FLORIDA THROUGH THIS PERIOD BUT NOW SHOW
THE MOISTURE FIELD SHIFTING NORTHWARD ON WEDNESDAY. THE NAM IS THE
MOST AGGRESSIVE WITH SIGNIFICANT DRYING OCCURRING AND IT SHOWS PWAT
DROPPING TO UNDER AN INCH WHEREAS THE GFS AND ECMWF HAVE THE PWAT
HOVERING IN THE 1.25 TO 1.5 INCH RANGE. SO THERE COULD STILL BE A
FEW SHOWERS BUT IF THE NAM VERIFIES THERE WILL BE LITTLE IN THE
WAY OF CLOUD COVER.
LONG TERM (THURSDAY-SUNDAY)...
THE MOST SIGNIFICANT CHANGE IN THE LONG TERM CONTINUES TO BE THE
THREAT OF A STRONGER COLD FRONT. ALL MODELS ARE IN GOOD AGREEMENT
THAT A STRONG MID LEVEL TROUGH WILL MOVE INTO NEW ENGLAND EARLY
FRIDAY WITH ITS TRAILING COLD FRONT MOVING THROUGH SOUTH FLORIDA.
HOWEVER, THERE ALSO CONTINUES TO BE SOME DISCREPANCY AS TO HOW
COOL IT WILL GET BEHIND THE FRONT. THE ECMWF IS STILL THE MOST
AGGRESSIVE AND SHOWING MUCH COOLER TEMPERATURES FOR THE REGION
FRIDAY AND SATURDAY MORNING THAN THE OPERATIONAL GFS WHICH IS THE
WARMER MODEL WITH A RANGE ON SATURDAY MORNING FROM THE MID TO
UPPER 40S WEST OF LAKE OKEECHOBEE TO THE MID 60S ALONG THE
SOUTHEAST COAST. BUT THE GFS ENSEMBLE RUN HAS A 15-20 DEGREE RANGE
BETWEEN THE COOLEST AND WARMEST PERTURBATIONS ACROSS SOUTH FLORIDA
WITH POSSIBLE UPPER 30S OVER GLADES AND HENDRY COUNTIES. SO AT
THIS TIME, IT CONTINUES TO BE A WAIT AND SEE APPROACH AND WILL
STAY CLOSE TO THE MEX NUMBERS UNTIL THE MODEL HAS SOME MORE
CONSISTENCY BETWEEN RUNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 80 68 78 69 / 20 20 20 20
FORT LAUDERDALE 79 70 77 72 / 20 20 20 20
MIAMI 81 70 78 71 / 20 20 20 20
NAPLES 77 64 76 64 / 20 20 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...60/BD
AVIATION/RADAR...71/JE
AREA FORECAST DISCUSSION
NWS MIAMI FL
630 AM EST MON DEC 30 2013
.AVIATION...
A SLOW MOVING BOUNDARY, STILL JUST TO THE NORTH OF LAKE
OKEECHOBEE, WILL CONTINUE TO BRING A MID DECK OF CLOUDS TO SOUTH
FLORIDA TODAY. THERE WILL ALSO BE SOME LINGERING FOG AND LOW CIGS
FOR THE FIRST COUPLE OF HOURS AFTER SUNRISE. OTHERWISE, EXPECTING
MVFR TO VFR CONDITIONS. THERE IS ALSO A SLIGHT CHANCE OF SOME
RAIN SHOWERS THROUGH THE TAF PERIOD, NOT INCLUDED IN THE TAFS DUE
TO THE PROBABLE LIGHT NATURE OF THE SHOWERS. WINDS WILL BE VARIABLE FOR A
GOOD PART OF THE DAY AS WELL. THEY DO SEEM TO FAVOR THE NORTHEAST
LATER TONIGHT.
&&
.PREV DISCUSSION... /ISSUED 306 AM EST MON DEC 30 2013/
SHORT TERM (TODAY-WEDNESDAY)...
A LARGE SCALE MID/UPPER LEVEL TROUGH COVERS MOST OF EASTERN NORTH
AMERICA AT THIS TIME WITH A WEAKENING COLD FRONT NEAR OR JUST
SOUTH OF LAKE OKEECHOBEE EARLY THIS MORNING. THIS FRONT WILL ONLY
SAG VERY SLOWLY SOUTH AND STALL ACROSS EXTREME SOUTH FLORIDA LATER
TODAY. THIS IS DUE TO THE FACT THAT THE SUBTROPICAL RIDGE WILL
REMAIN ANCHORED ACROSS THE CARIBBEAN AND EXTEND NORTHEAST OVER
EASTERN CUBA AND INTO THE CENTRAL ATLANTIC. SOME PATCHY DENSE FOG
AND A LOW STRATUS DECK HAVE DEVELOPED ACROSS MUCH OF SOUTH FLORIDA
THIS MORNING AS A SURFACE BASED INVERSION HAS FORMED ALONG AND
AHEAD OF THE FRONT. EVEN AS THESE CLOUDS MIX OUT SHORTLY AFTER
SUNRISE, ABUNDANT MID LEVEL CLOUDS WILL LINGER WITH THE STALLING
FRONT AND POSSIBLY A FEW SHOWERS. THE NAM IS SUFFERING FROM ITS
TYPICAL MESOSCALE BIAS AND ITS HIGH POPS SEEM WAY OUT OF LINE AND
WENT MUCH CLOSER TO THE GFS AND ECMWF SOLUTIONS. THE HRRR ALSO
WAS NOT SHOWING MUCH SHOWER ACTIVITY THROUGH 16Z ALTHOUGH IT HAS
NOT RUN SINCE 01Z. STRONGER HIGH PRESSURE WILL BUILD OVER THE
SOUTHEAST STATES ON TUESDAY AS THE REMAINS OF AN ARCTIC COLD FRONT
MOVE INTO NORTH FLORIDA AND IT TOO WILL RAPIDLY BECOME DIFFUSE AS
THE RIDGE TO OUR SOUTH MOVES LITTLE. THIS WILL CREATE BREEZY
CONDITIONS ALONG OR NEAR THE ATLANTIC COAST WITH A FEW POSSIBLE
SHOWERS MOVING ONSHORE. BY NEW YEARS` DAY, A MID LEVEL TROUGH THAT
IS CURRENTLY OVER NORTHERN MEXICO WILL LIFT TO THE NORTHEAST INTO
THE SOUTHERN TIER OF STATES GENERATING A SURFACE LOW IN THE GULF
OF MEXICO. THE MODELS HAD BEEN INDICATING THE BAND OF MOISTURE
WOULD LINGER ACROSS SOUTH FLORIDA THROUGH THIS PERIOD BUT NOW SHOW
THE MOISTURE FIELD SHIFTING NORTHWARD ON WEDNESDAY. THE NAM IS THE
MOST AGGRESSIVE WITH SIGNIFICANT DRYING OCCURRING AND IT SHOWS PWAT
DROPPING TO UNDER AN INCH WHEREAS THE GFS AND ECMWF HAVE THE PWAT
HOVERING IN THE 1.25 TO 1.5 INCH RANGE. SO THERE COULD STILL BE A
FEW SHOWERS BUT IF THE NAM VERIFIES THERE WILL BE LITTLE IN THE
WAY OF CLOUD COVER.
LONG TERM (THURSDAY-SUNDAY)...
THE MOST SIGNIFICANT CHANGE IN THE LONG TERM CONTINUES TO BE THE
THREAT OF A STRONGER COLD FRONT. ALL MODELS ARE IN GOOD AGREEMENT
THAT A STRONG MID LEVEL TROUGH WILL MOVE INTO NEW ENGLAND EARLY
FRIDAY WITH ITS TRAILING COLD FRONT MOVING THROUGH SOUTH FLORIDA.
HOWEVER, THERE ALSO CONTINUES TO BE SOME DISCREPANCY AS TO HOW
COOL IT WILL GET BEHIND THE FRONT. THE ECMWF IS STILL THE MOST
AGGRESSIVE AND SHOWING MUCH COOLER TEMPERATURES FOR THE REGION
FRIDAY AND SATURDAY MORNING THAN THE OPERATIONAL GFS WHICH IS THE
WARMER MODEL WITH A RANGE ON SATURDAY MORNING FROM THE MID TO
UPPER 40S WEST OF LAKE OKEECHOBEE TO THE MID 60S ALONG THE
SOUTHEAST COAST. BUT THE GFS ENSEMBLE RUN HAS A 15-20 DEGREE RANGE
BETWEEN THE COOLEST AND WARMEST PERTURBATIONS ACROSS SOUTH FLORIDA
WITH POSSIBLE UPPER 30S OVER GLADES AND HENDRY COUNTIES. SO AT
THIS TIME, IT CONTINUES TO BE A WAIT AND SEE APPROACH AND WILL
STAY CLOSE TO THE MEX NUMBERS UNTIL THE MODEL HAS SOME MORE
CONSISTENCY BETWEEN RUNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 80 68 78 69 / 20 20 20 20
FORT LAUDERDALE 79 70 77 72 / 20 20 20 20
MIAMI 81 70 78 71 / 20 20 20 20
NAPLES 77 64 76 64 / 20 20 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...30/KOB
AVIATION/RADAR...13/SI
AREA FORECAST DISCUSSION
NWS MIAMI FL
306 AM EST MON DEC 30 2013
.SHORT TERM (TODAY-WEDNESDAY)...
A LARGE SCALE MID/UPPER LEVEL TROUGH COVERS MOST OF EASTERN NORTH
AMERICA AT THIS TIME WITH A WEAKENING COLD FRONT NEAR OR JUST
SOUTH OF LAKE OKEECHOBEE EARLY THIS MORNING. THIS FRONT WILL ONLY
SAG VERY SLOWLY SOUTH AND STALL ACROSS EXTREME SOUTH FLORIDA LATER
TODAY. THIS IS DUE TO THE FACT THAT THE SUBTROPICAL RIDGE WILL
REMAIN ANCHORED ACROSS THE CARIBBEAN AND EXTEND NORTHEAST OVER
EASTERN CUBA AND INTO THE CENTRAL ATLANTIC. SOME PATCHY DENSE FOG
AND A LOW STRATUS DECK HAVE DEVELOPED ACROSS MUCH OF SOUTH FLORIDA
THIS MORNING AS A SURFACE BASED INVERSION HAS FORMED ALONG AND
AHEAD OF THE FRONT. EVEN AS THESE CLOUDS MIX OUT SHORTLY AFTER
SUNRISE, ABUNDANT MID LEVEL CLOUDS WILL LINGER WITH THE STALLING
FRONT AND POSSIBLY A FEW SHOWERS. THE NAM IS SUFFERING FROM ITS
TYPICAL MESOSCALE BIAS AND ITS HIGH POPS SEEM WAY OUT OF LINE AND
WENT MUCH CLOSER TO THE GFS AND ECMWF SOLUTIONS. THE HRRR ALSO
WAS NOT SHOWING MUCH SHOWER ACTIVITY THROUGH 16Z ALTHOUGH IT HAS
NOT RUN SINCE 01Z. STRONGER HIGH PRESSURE WILL BUILD OVER THE
SOUTHEAST STATES ON TUESDAY AS THE REMAINS OF AN ARCTIC COLD FRONT
MOVE INTO NORTH FLORIDA AND IT TOO WILL RAPIDLY BECOME DIFFUSE AS
THE RIDGE TO OUR SOUTH MOVES LITTLE. THIS WILL CREATE BREEZY
CONDITIONS ALONG OR NEAR THE ATLANTIC COAST WITH A FEW POSSIBLE
SHOWERS MOVING ONSHORE. BY NEW YEARS` DAY, A MID LEVEL TROUGH THAT
IS CURRENTLY OVER NORTHERN MEXICO WILL LIFT TO THE NORTHEAST INTO
THE SOUTHERN TIER OF STATES GENERATING A SURFACE LOW IN THE GULF
OF MEXICO. THE MODELS HAD BEEN INDICATING THE BAND OF MOISTURE
WOULD LINGER ACROSS SOUTH FLORIDA THROUGH THIS PERIOD BUT NOW SHOW
THE MOISTURE FIELD SHIFTING NORTHWARD ON WEDNESDAY. THE NAM IS THE
MOST AGGRESSIVE WITH SIGNIFICANT DRYING OCCURRING AND IT SHOWS PWAT
DROPPING TO UNDER AN INCH WHEREAS THE GFS AND ECMWF HAVE THE PWAT
HOVERING IN THE 1.25 TO 1.5 INCH RANGE. SO THERE COULD STILL BE A
FEW SHOWERS BUT IF THE NAM VERIFIES THERE WILL BE LITTLE IN THE
WAY OF CLOUD COVER.
.LONG TERM (THURSDAY-SUNDAY)...
THE MOST SIGNIFICANT CHANGE IN THE LONG TERM CONTINUES TO BE THE
THREAT OF A STRONGER COLD FRONT. ALL MODELS ARE IN GOOD AGREEMENT
THAT A STRONG MID LEVEL TROUGH WILL MOVE INTO NEW ENGLAND EARLY
FRIDAY WITH ITS TRAILING COLD FRONT MOVING THROUGH SOUTH FLORIDA.
HOWEVER, THERE ALSO CONTINUES TO BE SOME DISCREPANCY AS TO HOW
COOL IT WILL GET BEHIND THE FRONT. THE ECMWF IS STILL THE MOST
AGGRESSIVE AND SHOWING MUCH COOLER TEMPERATURES FOR THE REGION
FRIDAY AND SATURDAY MORNING THAN THE OPERATIONAL GFS WHICH IS THE
WARMER MODEL WITH A RANGE ON SATURDAY MORNING FROM THE MID TO
UPPER 40S WEST OF LAKE OKEECHOBEE TO THE MID 60S ALONG THE
SOUTHEAST COAST. BUT THE GFS ENSEMBLE RUN HAS A 15-20 DEGREE RANGE
BETWEEN THE COOLEST AND WARMEST PERTURBATIONS ACROSS SOUTH FLORIDA
WITH POSSIBLE UPPER 30S OVER GLADES AND HENDRY COUNTIES. SO AT
THIS TIME, IT CONTINUES TO BE A WAIT AND SEE APPROACH AND WILL
STAY CLOSE TO THE MEX NUMBERS UNTIL THE MODEL HAS SOME MORE
CONSISTENCY BETWEEN RUNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 80 68 78 69 / 20 20 20 20
FORT LAUDERDALE 79 70 77 72 / 20 20 20 20
MIAMI 81 70 78 71 / 20 20 20 20
NAPLES 77 64 76 64 / 20 20 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR FAR SOUTH
MIAMI DADE-INLAND BROWARD-INLAND COLLIER-INLAND MIAMI DADE-
METRO BROWARD.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...30/KOB
AVIATION/RADAR...13/SI
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
936 PM CST TUE DEC 31 2013
.UPDATE...
ISSUED AT 915 PM CST TUE DEC 31 2013
JUST SENT AN UPDATED WSW AND GRIDS REMOVING EASTERN IOWA COUNTIES
FROM TONIGHTS WSW. THE ADVISORY CONTINUES FROM DUBUQUE...JACKSON
AND CLINTON COUNTIES EAST.
THE FGEN FORCED SNOW THAT HAD BEEN ONGOING ALONG THE HIGHWAY 20
CORRIDOR THIS EVENING HAS SHIFTED EAST AND DEVELOPED FURTHER
SOUTH. SHORT RANGE MODELS INCLUDING THE 00Z/RAP13 AND HRRR HAVE
CAPTURED THIS TREND AND SUPPORT LITTLE IF ANY ADDITIONAL SO
TONIGHT FURTHER WEST. ADDITIONAL ACCUMULATIONS FOR MOST OF THE
AREA WHERE THE ADVISORY REMAINS IN EFFECT WILL PROBABLY BE LESS
THAN AN INCH. HOWEVER WITH THE BANDED NATURE OF THE SNOW...THERE
WILL LIKELY BE SOME NARROW SWATHS OF AN INCH OR TWO ADDITIONAL
SNOWFALL BY 12Z WEDNESDAY.
NO CHANGES WERE MADE TO THE WEDNESDAYS GRIDS INCLUDING SNOWFALL
WITH THE 00Z NAM STILL SUPPORTING A DECENT SNOW FALL CENTRAL AND
SOUTH NEW YEARS DAY.
&&
.SYNOPSIS...
ISSUED AT 304 PM CST TUE DEC 31 2013
THE NARROW AXIS OF MODERATE SNOW IS POSITIONED IN THE NORTHERN 1/4
OF THE CWA BY MID AFTERNOON. BY OBSERVATIONS...WEBCAMS AND
CALLS...THERE HAS BEEN ROUGHLY 1 INCH PER HOUR FALLING IN THIS AREA
SINCE AROUND NOON. FARTHER SOUTH...A STRONG STATIONARY FRONT IS
LOCATED NEAR THE IOWA/MISSOURI BORDER...EASILY SEEN IN OBS THAT
RANGE FROM THE MID 30S TO THE MID TEENS IN A FEW TENS OF MILES IN
OUR SOUTH. STRONG FRONTOGENESIS IS CAUSING THE SNOW TO THE NORTH OF
THE FRONT...AND THIS TYPE OF FORCING WILL ALSO DOMINATE TOMORROW.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 304 PM CST TUE DEC 31 2013
FRONTOGENESIS WILL CONTINUE THROUGH AROUND 9 PM IN THE NORTH...THEN
WILL SLOWLY SETTLE SOUTH IN A WEAKENING FASHION. THIS SHOULD LEAD TO
LIGHTER SNOWS AFTER MID EVENING...BUT WITH 3 TO 5 ALREADY ON THE
GROUND IN THE NORTH...WILL CONTINUE THE ADVISORY THROUGH 12Z.
FARTHER SOUTH ALONG THE HIGHWAY 30 TO INTERSTATE 80 CORRIDORS...THE
BEST CHANCE FOR MEASUREABLE SNOW WILL HOLD OFF UNTIL THIS FORCING
ARRIVES FROM THE NORTH MID EVENING. OVERNIGHT SNOW TOTALS SHOULD BE
1 TO 2 INCHES NORTHEAST TO AN INCH OR INTO THE CENTRAL CWA.
ANOTHER...ARGUABLY STRONGER ROUND OF FRONTOGENESIS ARRIVES EARLY
WEDNESDAY MORNING...LIKELY CONTINUING ALL DAY AS IS GRADUALLY
SETTLES SOUTH. THIS TOO SHOULD HAVE SNOW RATIOS OF 15 TO 20:1...AND
AMOUNTS OF SNOW WILL BE RATHER FLUFFY. THE NAM AND GEM BOTH CARRIED
THIS IDEA IN PAST RUNS AND CURRENT...BUT IS NOW SUPPORTED BY THE 12Z
GFS...12Z ECMWF...12Z UKMET...NMM EAST...SPC WRF AND LAST HOURS OF
THE RAP RUNS. THUS...WE HAVE HIGH ENOUGH CONFIDENCE ISSUE A WINTER
WEATHER ADVISORY SNOW OVER CENTRAL CWA FROM 6 AM WEDNESDAY TO 6 PM
WEDNESDAY. WE ARE GENERALLY LOOKING FOR 3 TO 4 INCHES OF SNOW IN A 6
HOUR WINDOW OF TIME. THIS SUPPORTS ADVISORY ISSUANCE. SHOULD THE
MESOCALE MODELS BE CORRECT ON THE STRENGTH OF FORCING...WE COULD BE
LOOKING AT AMOUNTS WITHIN THE BAND FROM OTTUMWA TO THE QUAD CITIES
IN THE 4 TO 7 INCH RANGE. HOWEVER...CONFIDENCE IS HIGHER FOR TOTALS
IN THE 3 TO 4 INCH RANGE. TEMPERATURES WILL BE VERY COLD AGAIN
TONIGHT AND WEDNESDAY...AS WINDS FROM THE NORTHEAST DRAW IN THE SAME
AIRMASS WE HAD YESTERDAY. THE WARMTH IN THE FAR SOUTH JUST IS NOT
COMING OUR WAY IN THIS FORECAST.
ERVIN
.LONG TERM...(WEDNESDAY NIGHT THROUGH NEXT TUESDAY)
ISSUED AT 304 PM CST TUE DEC 31 2013
WEDNESDAY NIGHT AND THURSDAY...LATEST 12Z RUN MODELS HAVE COME
AROUND WITH RESPECT TO EXTENT OF FORCING ACRS AND SOUTH OF THE CWA
WED EVENING AS UPPER VORT PIVOTS IN TROF BASE ACRS SOUTHEAST IA.
DECENT ELEVATED FRONTOGENESIS RIBBON ALONG AND NORTH OF CENTRAL IL
INTO SOUTHEASTERN PLAINS SFC FRONT...ALONG WITH ISENTROPIC LIFT
ANALYSIS ON 285K SFC SHOULD LAY DOWN AN ADDITIONAL 0.5 UP TO OVER AN
INCH IN THE SOUTHEASTERN QUARTER OF THE DVN CWA FROM 00Z-03Z OR SO
AND WORRIED IT MAY BE MORE TAKING INTO ACCOUNT USED 17:1 OR
HIGHER LSR/S. BUT FOR NOW WILL ALLOW THE ADVISORY END AT 00Z
COORDINATING WITH THE ABOVE SHORT TERM DISCUSSION. THUS EVEN THE
HWY 34 CORRIDOR AND AREAS TO THE SOUTH MAY END UP WITH 1-3 INCHES BY
MIDNIGHT THU NIGHT TAKING INTO ACCOUNT SNOWFALL LATE WED AFTERNOON
AND INTO THE EVENING. THEN AS L/W PHASING PROCESS SHIFTS OFF TO THE
EAST/SOUTHEAST OF THE REGION...ANOTHER BOUT OR INCOMING ARCTIC
HIGH PRESSURE TO DEAL WITH...WITH THE PRESSURE GRADIENT INDUCING OR
MAINTAINING 7-11KT WINDS INTO THU MORNING. SIDING WITH THE COOLER
MAV BUT GOING ABOVE IT TAKING INTO ACCOUNT MIXING WINDS AND
LINGERING CLOUD COVER...STILL MANY SUBZERO READINGS WILL OCCUR OVER
THE NORTHWESTERN THIRD OF THE CWA IN DEEPER SNOWPACK...MAY NOT BE
GOING COLD ENOUGH ALONG THE I80 CORRIDOR. THESE COLD AMBIENT TEMPS
WHEN COMBINED WITH THE WINDS WILL PROBABLY MAKE FOR WIND CHILL
ADVISORY CRITERIA EARLY THU MORNING. BOTH THE 12Z GFS AND ECMWF
SLIDE MAIN SFC RIDGE AXIS ACRS CENTRAL INTO EASTERN IA BY 00Z FRI
MAKING FOR SOME CLOUD CLEAR OUT AS THU PROGRESSES. HIGHS ONLY TO
RECOVER INTO THE SINGLE DIGITS ABOVE ZERO IN MUCH OF THE CWA. THEN
THE STAGE WILL BE SET FOR A NEAR RECORD COLD ARCTIC NIGHT THU NIGHT
INTO FRI MORNING AND AGAIN WILL SIDE WITH THE MUCH COLDER MAV MOS
GUIDANCE VALUES. CID MAY HAVE THE BEST CHC OF BREAKING IT/S RECORD
FOR THE 3RD OF JAN BEING -15F. ALTHOUGH THE WINDS SHOULD BE
DECOUPLING...EVEN 5 KT WINDS WILL PRODUCE SOLID WIND CHILL ADVISORY
AND POSSIBLE EVEN SOME WIND CHILL WARNING CRITERIA LATE THU NIGHT
AFTER 06Z INTO MID FRI MORNING.
FRIDAY THROUGH SUNDAY...ARCTIC RIDGE PROGGED TO MIGRATE OFF TO THE
EAST ON FRI WHICH WILL ALLOW RATHER ROBUST LLVL SOUTHERLY RETURN FLOW
TO BRING ABOUT A SUBSTANTIAL SFC TEMP MODERATION. AFTER SUCH A
FRIGID START TO THE MORNING...12 HR HIGHS WILL OCCUR AT AROUND 00Z
SAT...AND 24 HR HIGHS PROBABLY THROUGH MIDNIGHT FRI NIGHT. THE
LATEST RUN MEDIUM RANGE SOLUTIONS THEN SUGGEST TEMPORARY
FLATTENING FLOW PATTERN TO USHER A MORE VIGOROUS WAVE ACRS THE
NORTHERN PLAINS INTO THE NORTHWESTERN GRT LKS INTO SAT MORNING. WAA
SHIELD OF PRECIP ASSOCIATED WITH THIS FEATURE SHOULD STAY TO THE
NORTH OF THE CWA FRI NIGHT. DISCREPANCIES POP UP WITH THIS SYSTEM/S
SFC FROPA THROUGH THE CWA BY SAT AFTERNOON. THE 12Z ECMWF MAINTAINS
A DRY FROPA...WHILE THE 12Z GFS HAS TRENDED WETTER WITH POST FRONTAL
BAN OF SNOWS ACRS AT LEAST THE NORTHWESTERN THIRD OF THE CWA SAT
AFTERNOON...POSSIBLY 1-3 INCHES OF SNOW ACCUM BY EARLY SAT
EVENING. WILL KEEP SLIGHT CHC TO CHC POPS GOING FOE EXPECTING THE
ECMWF TO TREND WETTER AND PRODUCE SOME PRECIP IN THE CWA. BEFORE
FROPA...MILDEST DAY IN THE PERIOD SAT WITH HIGHS IN THE MID 20S IN
THE NORTH...TO THE LOWER 30S IN THE SOUTH. WOULD BE WARMER IF IT
WERE NOT FOR THE SNOWPACK. RE-ESTABLISHING L/W TROF BASE SOMEWHERE
ACRS THE MID CONUS AND PROBABLY WEST OF OF THE MS RVR VALLEY...AND
WAVE ENERGY EJECTING OUT OF THE DEEP PLAINS LATE SAT NIGHT AND INTO
SUNDAY WILL BE A WINDOW TO WATCH FOR FURTHER NORTHWEST PULL OUT
PATHWAY. RIGHT NOW THE LATEST GFS/ECMWF AND ENSEMBLES JUST CLIP THE
FAR SOUTHERN AND SOUTHEASTERN CWA WITH 1-2+ INCHES BY SUNDAY
AFTERNOON. NORTHERLY LLVL COLD CONVEYOR WRAPPING IN AROUND THIS
FEATURE TO BRING ABOUT COLDER TEMPS AGAIN SAT NIGHT AND SUNDAY.
THEN BULK OF THE MEDIUM RANGE MODELS CONTINUE TO ADVERTISE A HUGELY
NEGATIVE ANOMALY IN THEIR L/W TROF FORMATION ACRS THE UPPER AND MID
MS RVR VALLEY BY 12Z MON. SEEMS THE POLAR VORTEX GYRATING ACRS THE
SOUTHERN HUDSON BAY REGION REMAINS TRAPPED AND ACTING AS A TYPE OF
BLOCK FOR RIDGING OFF THE COASTS.
NEXT MONDAY AND TUESDAY...THE 12Z GFS HAD AN INCREDIBLY INTENSE SFC
HIGH OF 1058 MB INTO NORTH CENTRAL MT BY 12Z MON...WITH THE RIDGE
CENTER THEN MODERATING TO THE LOWER 1040S AS IT SLIDES SOUTHEASTWARD
ACRS THE REGION FOR MON NIGHT INTO TUE MORNING. THE EURO NOT QUITE
SO STRONG WITH A 1045 MB HIGH...BUT THEY BOTH ADVERTISE ARCTIC DOME
OF AIR TO SURGE ACRS THE CWA/FROPA AS MONDAY PROGRESSES. SHARPLY
DROPPING TEMPS...AND IF THE MODEL PROGGED -26C TO -28C H85 MB
AIRMASS VERIFIES AND MAKE IT ACRS THE CWA...COULD BE SOME -15 TO
-25F LOW TEMPS BY TUE MORNING IN PORTIONS OF THE DVN CWA. INCREDIBLE
COLD. WILL IT MODERATE THEN MID TO LATE NEXT WEEK AS BULK OF THE
MEDIUM RANGE SOLUTIONS SUGGEST...OR THEY CONTINUE TO MISHANDLE SUCH
A NEG ANOMALY REGIME AND OPEN THE REGION/MIDWEST BACK TO MORE ARCTIC
DUMPS AFTER NEXT WED. ..12..
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 915 PM CST TUE DEC 31 2013
UPDATED THE NORTHERN TAFS FOR MORE OPTIMISTIC CONDITIONS FOR THE
REST OF THE EVENING AND EARLY WEDNESDAY MORNING. THE SNOW OVER
NORTHWEST ILLINOIS INTO EASTERN IOWA CONTINUES TO DIMINISH WEST OF
THE MISSISSIPPI RIVER. SHORT RANGE MODELS SUGGEST THIS TREND WILL
CONTINUE FOR MOST OF THE NIGHT. KDBQ/KCID TAFS WERE AMENDED FOR
MAINLY VFR CONDITIONS UNTIL THE PRE-DAWN HOURS OF WEDNESDAY. MORE
SNOW WILL SPREAD OVER THE AREA LATE TONIGHT AND WILL CONTINUE
WEDNESDAY. THE BULK OF THIS SNOW SHOULD FALL ALONG AND SOUTH OF I80
AND HAVE INDICATED THIS IN THE TAFS WITH CONDITIONS AT KMLI AND
KBRL DETERIORATING TO IFR AND LIFR BY LATE WEDNESDAY MORNING.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WINTER WEATHER ADVISORY UNTIL 6 AM CST WEDNESDAY FOR DUBUQUE-
JACKSON.
WINTER WEATHER ADVISORY FROM 6 AM TO 6 PM CST WEDNESDAY FOR
CEDAR-DES MOINES-HENRY IA-IOWA-JEFFERSON-JOHNSON-KEOKUK-
LOUISA-MUSCATINE-SCOTT-WASHINGTON.
WINTER WEATHER ADVISORY UNTIL 6 PM CST WEDNESDAY FOR CLINTON.
IL...WINTER WEATHER ADVISORY UNTIL 6 AM CST WEDNESDAY FOR JO DAVIESS-
STEPHENSON.
WINTER WEATHER ADVISORY FROM 6 AM TO 6 PM CST WEDNESDAY FOR
BUREAU-HENRY IL-MERCER-PUTNAM-ROCK ISLAND.
WINTER WEATHER ADVISORY UNTIL 6 PM CST WEDNESDAY FOR CARROLL-
WHITESIDE.
MO...NONE.
&&
$$
UPDATE...DLF
SYNOPSIS...ERVIN
SHORT TERM...ERVIN
LONG TERM...12
AVIATION...DLF
AREA FORECAST DISCUSSION
NWS GRAY ME
1154 PM EST SUN DEC 29 2013
.SYNOPSIS...
LOW PRESSURE WILL MOVE RAPIDLY THROUGH THE GULF OF MAINE OVERNIGHT
AND BE LOCATED NEAR HALIFAX NOVA SCOTIA BY MONDAY MORNING. HIGH
PRESSURE WILL BUILD OVER THE REGION MONDAY. WEAK LOW PRESSURE WILL
MOVE THROUGH CENTRAL NEW ENGLAND TUESDAY AFTERNOON. HIGH PRESSURE
WILL BUILD OVER THE REGION WEDNESDAY. LOW PRESSURE WILL GATHER
STRENGTH OVER THE MID ATLANTIC STATES THURSDAY AND MOVE NORTHEAST
SOUTH OF CAPE COD FRIDAY. HIGH PRESSURE WILL BUILD OVER THE
NORTHEAST SATURDAY AND MOVE SOUTHEAST OF THE REGION SUNDAY.
&&
.NEAR TERM /UNTIL 7 AM MONDAY MORNING/...
1150 PM...SNOW WAS ENDING RAPIDLY FROM SOUTHWEST TO NORTHEAST
ACROSS THE FORECAST AREA. ALL WINTER WEATHER HEADLINES FROM THE
PORTLAND AREA AND POINTS WEST AND SOUTHWEST WERE DROPPED WITH THIS
ESTF UPDATE.
PREV DISC...
UPDATED TO DROP THE WINTER WX HEADLINES FOR COASTAL CUMBERLAND AND
COASTAL YORK COUNTIES IN SW MAINE AND FOR INTERIOR ROCKINGHAM
COUNTY IN SE NH. PRCP HAS BEEN MOSTLY RAIN WITH SOME MIX OR CHANGE
OVER TO SN BUT ANY ACCUMULATIONS HAVE BEEN AN OR OR LESS FOR THESE
AREAS WITH PERHAPS A COUPLE INCHES WELL AWAY FROM THE COAST. ANY
ADDITIONAL SNOW ACCUMULATIONS WILL GIVE TOTALS NO MORE THAN 2-4
INCHES IN THESE AREAS...WITH EVEN LESS ALONG THE SHORE LINE.
PREVIOUS DISCUSSION...
UPDATED TO INPUT LATEST OBSERVED DATA. STILL SEEING MIXED PRCP OR
RAIN SRN NH AND COASTAL INTO ADJACENT INTERIOR AREAS THIS EVE.
BACK EDGE OF PRCP ALREADY MOVING INTO NY STATE AS SUPPORTED BY
MODELS MOVING SYSTEM THRU REAL FAST...BY 06Z IT`S OVER FOR ALL BUT
MAYBE EXTREME ERN ZONES. WILL BE TOUGH TO GET HIGH SNOW TOTALS...
ESPECIALLY WITH RAIN AND MIXED AT THIS TIME WHICH WILL CUT INTO
TOTAL QPF AMOUNTS AVBL FOR PRODUCING SNOW. WON`T BACK OFF ON
HEADLINES YET...BUT WILL BE UPDATING THIS EVE AS THINGS PROGRESS.
PREVIOUS DISCUSSION...
COLD FRONT HAS PUSHED SOUTH THROUGH THE MIDCOAST AND IS NOW
LOCATED FROM WISCASSET TO LEWISTON BEFORE GETTING HUNG UP IN THE
HILL COUNTRY NEAR RUMFORD. TEMPERATURES BEHIND THE FRONT HAVE BEEN
FALLING INTO THE MID 20S AS NOTED OVER THE PAST FEW HOURS AT
BANGOR AND WATERVILLE. THIS FRONT MAY PLAY A KEY ROLE IN
DETERMINING PRECIPITATION TYPE ACROSS THE MIDCOAST REGION TONIGHT.
LOW PRESSURE CURRENTLY JUST SOUTHEAST OF PHILADELPHIA WILL TRACK
QUICKLY NORTHEAST ACROSS CAPE COD AND TO NOVA SCOTIA TONIGHT.
LARGE AREA OF PRECIPITATION HAS SPREAD NORTHWARD AHEAD OF THIS
LOW... NOW SPREADING ACROSS ALL OF SOUTHERN NEW ENGLAND AND
PUSHING INTO SOUTHERN NEW HAMPSHIRE. THIS PRECIPITATION WILL
CONTINUE TO SPREAD NORTHEAST ACROSS NEW HAMPSHIRE AND MAINE
OVERNIGHT... BRINGING A QUICK... BUT HEAVY... ROUND OF
PRECIPITATION BEFORE EXITING JUST AFTER MIDNIGHT.
PRECIPITATION TYPE CONTINUES TO BE A COMPLEX PICTURE WITH THIS
STORM... AS TEMPERATURES THROUGH THE LOWEST FEW THOUSAND FEET WILL
BE NEAR FREEZING ACROSS MUCH OF SOUTHERN NEW HAMPSHIRE AND COASTAL
MAINE. NAM AND HRRR MODELS CONTINUE TO SHOW A COLDER SOLUTION...
WITH TEMPERATURES AT OR JUST BELOW FREEZING AS PRECIPITATION FALLS
THIS EVENING. IT IS EXPECTED THAT AS PRECIPITATION BEGINS TO
INTENSIFY... TEMPERATURES WITHIN THE ATMOSPHERIC PROFILE WILL COOL
AND ALLOW A HEAVY WET SNOW TO FALL. LOTS OF MOISTURE AND GOOD
DYNAMICS WITH THIS SYSTEM WILL ALLOW INTENSE PRECIPITATION
RATES... WITH TOTAL QPF TONIGHT RANGING FROM 0.75 TO 1.00 INCH.
SNOW RATIOS WILL BE NEAR 10 TO 1 DUE TO THE LARGE ISOTHERMAL LAYER
IN THE LOW LEVELS ESPECIALLY OVER SOUTHERN AND CENTRAL NEW
HAMPSHIRE EXTENDING TO THE MAINE COAST. NORTH OF THE PREVIOUSLY
MENTIONED COLD FRONT... TEMPERATURES WILL BE A BIT COLDER...
LEADING TO MORE CERTAINTY THAT PRECIPITATION WILL FALL IN THE FORM
OF SNOW AND ALLOW SNOW RATIOS TO BE A BIT HIGHER... POSSIBLY 13 TO
1.
THERE IS A GOOD AMOUNT OF CONFIDENCE THAT A BAND OF 6 TO 10 INCHES
OF SNOW WILL FALL... THOUGH THE TRANSITION TO RAIN NEAR THE COAST
IS STILL THE BIGGEST QUESTION MARK. IT IS POSSIBLE THAT THE
IMMEDIATE COASTLINE MAY SEE ONLY AN INCH OR TWO OF SNOW WHILE
AREAS JUST INLAND COULD SEE 6 TO 10. WITH THE COLDER FORECAST...
THE WINTER STORM WARNINGS HAVE BEEN EXTENDED TO THE COAST FROM
PORTLAND EASTWARD. THIS AREA WAS ALSO HIT HARD BY THE ICE STORM
LAST WEEKEND AND THE TREES ARE LIKELY STILL SUPPORTING A LOAD OF
ICE FROM THIS. WITH THE ADDITIONAL STICKY... WET SNOW EXPECTED...
THIS COULD CAUSE ADDITIONAL POWER OUTAGES EVEN IF THE 6 INCH
WARNING CRITERIA IS NOT MET.
SNOWFALL RATES WILL LIKELY BE QUITE INTENSE THIS EVENING... WITH 1
TO 2 INCHES PER HOUR COMMON AND RATES UP TO 3 INCHES PER HOUR
POSSIBLE. THIS WILL MAKE IT MORE DIFFICULT FOR ROAD CREWS TO KEEP
UP WITH SNOW REMOVAL DURING THE HEAVIEST PERIOD OF SNOW... CAUSING
EVEN GREATER IMPACTS ON TRAVEL. ALL THESE FACTORS WERE CONSIDERED
IN THE PLACING OF WINTER STORM WARNINGS AND WINTER WEATHER ADVISORIES.
FURTHER TO THE NORTH... THERE WILL LIKELY BE A SHARP CUT OFF IN
SNOWFALL AMOUNTS INLAND OF THE HEAVIEST BAND. LOCATIONS NEAR THE
CANADIAN BORDER MAY NOT SEE MUCH SNOW AT ALL... AND NORTHERN COOS
COUNTY HAS BEEN DROPPED FROM THE ADVISORY AS FORECAST SNOWFALL
AMOUNTS IN THIS REGION ARE ONLY 1 TO 2 INCHES. THE NORTHERN ZONES
IN WESTERN MAINE WERE LEFT IN AS THE SOUTHERN PORTION OF THESE
ZONES STILL HAS A THREAT FOR HIGHER TOTALS.
&&
.SHORT TERM /7 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
AS LOW PRESSURE MOVES EAST... A COLD FRONT WILL PUSH SOUTHEAST
ACROSS NEW ENGLAND ON MONDAY. A VERY COLD AIR MASS HAS BEEN
LURKING BEHIND THIS FRONT... AND THIS WILL BE FELT IN FULL FORCE
BY MONDAY AFTERNOON. TEMPERATURES WILL LIKELY BE FALLING THROUGH
THE DAY AS COLD ADVECTION TAKES OVER. WINDS COULD GUST TO 25 MPH
AS COLD ADVECTION ALLOWS GOOD MIXING TO TAKE PLACE.
TEMPERATURES FALL TO NEAR OR BELOW ZERO ACROSS THE ENTIRE FORECAST
AREA MONDAY NIGHT. READINGS AS COLD AS 20 BELOW ARE POSSIBLE TO
THE NORTH OF THE MOUNTAINS WHERE COLD AIR WILL BE EVEN MORE
INTENSE. WIND CHILL ADVISORIES OR WARNINGS MAY BE NEEDED AS WIND
CHILLS COULD REACH 30 BELOW.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
MODELS IN AGREEMENT THROUGH THE PERIOD FOR A COLD WEEK. A WEAK SHORT
WAVE WILL MOVE THROUGH NEW HAMPSHIRE AND MAINE TUESDAY AFTERNOON
WITH ASSOCIATED SNOW SHOWERS AND USHER IN EVEN COLDER AIR. WIND
CHILL ADVISORIES MAY BE NEEDED TUESDAY NIGHT AND WEDNESDAY. HIGH
PRESSURE CRESTS OVERHEAD WEDNESDAY. LATE IN THE DAY CLOUDS STREAM
EAST. LIGHT SNOW DEVELOPS THURSDAY AS LOW PRESSURE DEVELOPS SOUTH
OF LONG ISLAND NEW YORK. GFS AND ECMWF SIMILAR IN THE TRACK AND
LINGER SNOW INTO FRIDAY. SEVERAL INCHES OF SNOW POSSIBLE WITH THIS
SYSTEM. ANOTHER ARCTIC SHOT OF AIR ARRIVES FRIDAY AFTERNOON AND
SATURDAY. A WARM FRONT WILL MOVE NORTH SUNDAY.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
SHORT TERM /THROUGH THURSDAY NIGHT/...VARIABLE CONDITIONS BUT
MOSTLY LIFR THIS EVE...IMPROVE FROM SW TO NE AROUND MIDNIGHT AS
PRCP COMES TO AN END FAIRLY QUICKLY FROM THIS FAST MOVING SYSTEM.
PRCP TYPE WILL BE PROBLEMATIC WITH MIXED WINTRY PRCP EXPECTED
ALONG WITH PRCP CHANGING FROM RAIN OR MIXED TO MIXED OR SNOW
BEFORE ENDING. IMPROVING TO VFR EXCEPT MVFR N/MT ZONES LATER TNGT
AND MONDAY. GUSTY NW WINDS PSBL MONDAY. VFR MONDAY NGT.
LONG TERM...POSSIBLE MVFR IN SNOW SHOWERS TUESDAY AND WEDNESDAY.
IFR MOVES IN THURSDAY AFTERNOON AND MOVES OUT FRIDAY. VFR
SATURDAY AND SUNDAY.
&&
.MARINE...
SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...UPDATED TO INPUT
LATEST OBSERVED DATA. WILL CONT HEADLINES...INCREASED WINDS PER
LATEST BUOY REPORTS. WINDS PICKING UP AS LOW HAS INTENSIFIED MORE
THAN WHAT MODELS HAD PREDICTED.
PREVIOUS DISCUSSION...
LOW PRESSURE MOVING FROM CAPE COD TO NOVA SCOTIA WILL BRING A
BRIEF PERIOD OF NORTHEAST WINDS WHICH COULD GUST TO GALE FORCE.
WINDS SHIFT TO NORTHWEST BY MORNING. A COLD FRONT PUSHING THROUGH
THE GULF OF MAINE ON MONDAY WILL BRING STRONG COLD ADVECTION AND
THE POTENTIAL FOR MORE GALE FORCE GUSTS THROUGH MONDAY EVENING.
LONG TERM...SMALL CRAFT WINDS TUESDAY AND WEDNESDAY. GALE FORCE
WINDS POSSIBLE THURSDAY AFTERNOON INTO SATURDAY MORNING.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER STORM WARNING UNTIL 4 AM EST MONDAY FOR MEZ013-014-
020>022-026>028.
WINTER WEATHER ADVISORY UNTIL 4 AM EST MONDAY FOR MEZ008-009.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 9 PM EST MONDAY FOR ANZ151-153.
GALE WARNING UNTIL 9 PM EST MONDAY FOR ANZ150-152-154.
&&
$$
ES
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
516 PM EST MON DEC 30 2013
.UPDATE...
ISSUED AT 512 PM EST MON DEC 30 2013
DESPITE DRY/STABLE NATURE OF ARCTIC AIRMASS SHOWN ON THE 12Z INL
RAOB AND RELATIVELY POOR SN GROWTH PARAMETERS...ISSUED A LK EFFECT
SN WARNING FOR NRN HOUGHTON COUNTY PER SFC REPORTS OF SN FALL RATES
OVER AN INCH/HR UNDER A HEAVY SN BAND SHOWN ON VSBL STLT IMAGERY
STREAMING FM THE BAYFIELD PENINSULA INTO THE N HALF OF HOUGHTON
COUNTY. THIS BAND APPEARS TO BE FOCUSED IN THE LLVL CNVGC BTWN A MORE
NW FLOW OBSVD AT THE MARINE SITES ON ISLE ROYALE AND WSW LAND BREEZE
FLOW TO THE S WITHIN VERY COLD ARCTIC AIRMASS OVER UPR MI. THE 18Z
CNDN MODEL APPEARS TO HAVE THE BEST HANDLE ON THE LOCATION OF THIS
FEATURE AND INDICATES THE FOCUSED LLVL CNVGC/HEAVY SN BAND WL SHIFT
ONLY SLOWLY S THRU THE NGT BEFORE DIMINISHING TOWARD 12Z. GIVEN OBS
AND POTENTIAL LONGER RESIDENCE TIME OF THE HEAVIER SN...OPTED TO GO
WITH WRNG THRU 12Z TUE AS TWO SPOTTERS IN CALUMET HAVE ALREADY
REPORTED 6 INCHES OF SN BTWN NOON AND 4-5PM.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 430 PM EST MON DEC 30 2013
MOST OF UPPER MICHIGAN IS QUIET BUT COLD THIS AFTERNOON...AS THE
AREA IS UNDER LINGERING AFFECTS OF THE HIGH PRESSURE RIDGE THAT
MOVED THROUGH LAST NIGHT INTO THIS MORNING. THIS HAS LED TO WINDS
BACKING TO THE WEST-SOUTHWEST IN THE BOUNDARY LAYER AND FOCUSED THE
REMAINING LAKE EFFECT OVER THE KEWEENAW AND RIGHT ALONG THE
SHORELINE NEAR GRAND MARAIS. CALLS TO THE KEWEENAW THIS AFTERNOON
INDICATE THAT THE FINE FLAKE LES IS STILL IN PLACE. WHILE THIS IS
GOOD AT REDUCING VISIBILITIES...ACCUMULATIONS HAVE BEEN LIGHT AND
UNDER A COUPLE INCHES. OVER THE WEST...TEMPERATURES HAVE STRUGGLE
TO EVEN REACH ZERO DEGREES THIS AFTERNOON...WHICH WILL PAVE THE WAY
FOR ANOTHER NIGHT WILL COLD WIND CHILLS. FARTHER TO THE
SOUTHWEST...A SHORTWAVE IS SLIDING EAST-SOUTHEAST THROUGH MINNESOTA
AT THIS TIME AND IS LEADING TO LIGHT SNOW SHOWERS. THESE -SHSN
SHOULD MISS MUCH OF THE AREA...BUT COULD LEAD TO A FEW FLURRIES
ALONG THE WISCONSIN BORDER.
A WEAK SURFACE TROUGH OVER CENTRAL/SOUTHERN LAKE SUPERIOR AT THIS
TIME WILL BE THE FOCUS FOR THE LAKE EFFECT TONIGHT INTO TUESDAY
MORNING. ALL THE HIGH RESOLUTION MODELS SHOW A MESO-LOW DEVELOPING
OVER THE SOUTHEASTERN LAKE THIS EVENING. A LOOK AT THE MONTREAL
RIVER RADAR THIS AFTERNOON DOESN/T INDICATE ANY CIRCULATION AT THIS
POINT...BUT IT SHOULD BE DEVELOPING THIS EVENING. IN ADDITION...THE
LAKE EFFECT SNOW WILL BE ENHANCED BY A SHORTWAVE MOVING THROUGH THIS
EVENING. THIS WAVE PROVIDES A LITTLE MORE MOISTURE AND MID LEVEL
UPWARD MOTION...ALONG WITH COOLING ALOFT TO WEAKEN THE INVERSION
CURRENTLY AROUND 6-8KFT AND ALLOWS IT TO RISE TO 10-12KFT OVER THE
EASTERN CWA. ALSO...IT HELPS INTENSIFY THE SURFACE TROUGH OR
MESO-LOW OVER THE EASTERN LAKE BEFORE IT SLIDES SOUTHEAST LATE
TONIGHT INTO TUESDAY MORNING (BUT STILL LEAVES A TROUGH OVER THE
EASTERN LAKE). SINCE THIS HAS BEEN SHOWN FOR SEVERAL DAYS
NOW...FAIRLY CONFIDENT ON ITS OCCURRENCE...THE QUESTION COMES DOWN
TO EXACT LOCATION OF THE HEAVIEST BAND AND WHAT THE SNOW RATIOS WILL
BE. LATEST TRENDS IN THE MODELS SHOW A SLIGHTLY LATER ARRIVAL OF
THE STRONG LES BAND ON THE WEST SIDE OF THE MESO-LOW...LIKELY
CLOSER TO 04-06Z. UNFORTUNATELY THE LOCATION IS ALL OVER
THE MAP...WITH SOME HAVE IT HITTING PICTURED ROCKS (AND
NEARLY MUNISING - RAP AND A COUPLE 15Z HOPWRF MEMBERS) WHILE OTHERS
THE FAR NORTHEAST PART OF LUCE COUNTY (2.5 AND 10KM REGIONAL GEMS).
OPTED TO FOCUS ON THE MIDDLE GROUND WHICH WAS SIMILAR TO THE
PREVIOUS FORECAST AND HAVE THE STRONG BAND COME ONSHORE AROUND THE
GRAND MARAIS AREA. PINNING DOWN THIS LOCATION WILL MAKE OR BREAK
SNOWFALL AMOUNTS AND THE POTENTIAL OF REACHING WARNING SNOWFALL
AMOUNTS. ONCE THIS BAND COMES ON SHORE EXPECT A TRANSITION TO A
GENERAL NORTHWEST FLOW LES THROUGH THE DAY ON TUESDAY. WITH A
WEAK SURFACE TROUGH LINGERING OVER THE FAR EASTERN LAKE...MODELS
ARE INDICATING SOME ENHANCED CONVERGENCE TO LEAD TO A STRONGER BAND
AFFECTING NORTHERN LUCE COUNTY...ALTHOUGH THERE WILL BE SOME
WAVERING EXPECTED.
AS FOR SNOW RATIOS AND AMOUNTS...ARCTIC AIR MASS WILL LIKELY BE
MODIFIED SOMEWHAT FROM THE CIRCULATION AND MOISTURE/HEAT FLUX OFF
THE LAKE...WHICH WILL TRY TO PUT SOME OF THE CLOUD INTO THE DGZ.
THUS...WOULD EXPECT SOME HIGHER RATIOS TONIGHT AS THE BAND
COMES ON SHORE AND BEFORE SLIGHTLY COOLER AIR ARRIVES ON
TUESDAY AND TRANSITION BACK TO MORE OF A FINER FLAKE SNOW THAT
WE HAVE SEEN THE LAST 24-48HRS. ON TO AMOUNTS...PREVIOUS FORECAST
WAS RIGHT ON THE EDGE OF BOTH 12/24HR AMOUNTS AND HAVE SIMILAR IF
NOT SLIGHTLY LOWER VALUES FOR THIS FORECAST. THINK THERE WILL BE A
GOOD BURST WITH THAT STRONG BAND TONIGHT INTO TUESDAY MORNING OF 3
TO 7 INCHES. THEN THE TRANSITION TO MORE NORTHWEST WINDS AND
SLIGHTLY LOWER RATIOS SHOULD LEAD TO ANOTHER PERIOD OF 2-6 INCHES
FROM MID MORNING INTO THE EARLY EVENING (BUT LIKELY FOCUSED FARTHER
EAST INTO LUCE COUNTY). THIS IS JUST PUTS THE FORECAST JUST UNDER
BOTH THE 12/24HR WARNING AMOUNTS AND WITH THE UNCERTAINTY IN THE
EXACT LOCATION OF THE HEAVIEST SNOW...WILL ISSUE A STRONGLY WORDED
ADVISORY FOR ALGER/LUCE AND NORTHERN SCHOOLCRAFT FOR TONIGHT INTO
TUESDAY. THAT WAY WE CAN HOPEFULLY GET ONE MORE LOOK AT HIGH RES
RUNS AND IF THERE IS A BETTER HANDLE ON LOCATION AND CONFIDENCE
GROWS ON WARNING AMOUNTS...CAN UPGRADE THIS EVENING OR TONIGHT FOR
THE MORE SPECIFIC LOCATION. WITH ALL OF THE LOCATION
DIFFERENCES...WOULD HATE TO ISSUE A WARNING FOR LUCE AND THEN HAVE
IT STAY MAINLY IN ALGER OR VICE-VERSA.
OVER THE WEST...A SURFACE TROUGH STRETCHED WEST ACROSS SOUTHERN
LAKE SUPERIOR WILL SLOWLY PUSH THE MAIN BAND AFFECTING THE KEWEENAW
SOUTH TONIGHT INTO THE ONTONAGON AND SOUTHERN PORTIONS OF HOUGHTON
COUNTY AREA TONIGHT. AS THIS OCCURS...THE REST OF THE KEWEENAW WILL
TRANSITION TO MORE OF A NW FLOW LAKE EFFECT SCENARIO WHICH WILL
CONTINUE INTO TUESDAY. LESS RESIDENCE TIME OVER WESTERN LAKE
SUPERIOR WILL LIMIT THE ARCTIC AIR MASS MODERATION AND SHOULD KEEP
MOST OF THE CLOUD LAYER ABOVE THE DGZ. THUS...WOULD EXPECT THE
SMALLER SNOW FLAKES AND RATIOS TO CONTINUE THERE AND LIMIT
ACCUMULATIONS. INVERSION HEIGHTS ARE GREATER THAN THE PAST 24HRS
(7-9KFT) WHICH WILL LEAD TO SLIGHTLY STRONGER SHOWERS...BUT ALL OF
THAT CLOUD LAYER WILL BE WELL ABOVE THE DGZ. CURRENT THOUGHT IS
THERE BEING AN INCREASE IN SNOW ACCUMULATION THIS EVENING...BEFORE
COLDER 850MB TEMPS MOVE IN BEHIND THE SHORTWAVE (FALLING TO ALMOST
-26C BY 12Z TUESDAY) AND PUSH ALL OF THE CLOUD ABOVE THE DGZ.
ALTHOUGH TOTAL AMOUNTS OVER THE 24 HOUR PERIOD MAY REACH THE 3-6INCH
RANGE...THINK 12HR AMOUNTS WILL BE HARD PRESSED TO REACH THE 4 INCH
AMOUNT NEEDED FOR A LES ADVISORY.
A COLD START TO THE DAY AND A TIGHTENING SURFACE GRADIENT WITH THE
SURFACE DROPPING SOUTH INTO NORTHERN UPPER MICHIGAN TONIGHT WILL
LEAD TO ANOTHER NIGHT OF VERY COLD WIND CHILLS. THINK THE SCATTERED
HIGH CLOUDS AND SLIGHTLY HIGHER WINDS WILL KEEP TEMPS SLIGHTLY
WARMER THAN LAST NIGHT. BUT THIS WILL ALSO KEEP WIND CHILLS LOW AND
SIMILAR TO LAST NIGHT. THEREFORE...HAVE ISSUED A WIND CHILL
ADVISORY FOR THE SAME LOCATIONS AS LAST NIGHT AND HAVE IT RUNNING
THROUGH LATE TUESDAY MORNING. ONCE AGAIN...TEMPERATURES WILL
STRUGGLE TO REBOUND TOMORROW AND SOME LOCATIONS OUT WEST WILL STAY
IN THE SINGLE DIGITS BELOW ZERO.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 430 PM EST MON DEC 30 2013
MODELS ARE CONSISTENT IN SHOWING THE 500MB CLOSED LOW OVER QUEBEC
WEDNESDAY MOVING OFF INTO THE ATLANTIC THURSDAY. THE GFS /AS USUAL/
IS MORE PROGRESSIVE THAN THE ECWMF WITH THE LONGWAVE TROUGH IN THE
WAKE OF THE LOW...BRINGING THE TROUGH THROUGH THE GREAT LAKES ON
THURSDAY AFTERNOON. THE ECMWF IS SLOWER AND DEEPER WITH THIS
TROUGH...WITH IT BEING MAINLY OVER WI ON THURSDAY AFTERNOON.
GUIDANCE SUGGESTS THAT THE ECMWF HAS BEEN ERRING ON THE DEEPER AND
MORE AMPLIFIED SIDE LATELY...HOWEVER...AND THIS MAY BE THE CASE.
OVERALL WENT MIDDLE OF THE ROAD FOR THE FORECAST AT THIS
POINT...LEANING MORE TOWARDS THE ECMWF. AS FAR AS WHAT THIS MEANS
FOR THE SURFACE...LOW PRESSURE DEVELOPS IN THE CENTRAL PLAINS AND
RIDES NORTHEASTWARD ALONG THE TROUGH...WHICH BRINGS AN INVERTED
SURFACE TROUGH INTO UPPER MI FOR WEDNESDAY NIGHT-THURSDAY AFTERNOON.
TUESDAY NIGHT WINDS REMAIN OUT OF THE WEST NORTHWEST THROUGH
MIDNIGHT...BEFORE GRADUALLY VEERING TO THE NORTH AND EVEN NORTHEAST
AS THE INVERTED TROUGH SHIFTS WESTWARD. THIS MOVES THE HIGHEST POPS
FROM THE FAR NORTHEASTERN PORTIONS OF THE COUNTY TOWARDS MUNISING
THROUGH THE NIGHT. BY WEDNESDAY AFTERNOON...CONVERGENCE FOCUSES
BETWEEN MARQUETTE AND MUNISING...WHICH IS WHERE HIGHEST POPS ARE
SITUATED IN THE GRIDS. WHILE THIS REMAINS THE CASE THROUGH THURSDAY
AFTERNOON...TOTAL ACCUMULATIONS ARE GENERALLY EXPECTED TO BE ON THE
ORDER OF 2 TO 4 INCHES BETWEEN SHOT POINT AND MUNISING. GIVEN THAT
MOST OF THE BANDS ARE SHIFTING FROM WEST-NORTHWEST INTO A MORE
NORTH-NORTHEAST PATTERN THROUGH THE PERIOD...NOT REALLY EXPECTING
ANY ONE LOCATION TO RECEIVE TOO MUCH ACCUMULATION. ALSO...BEYOND
WEDNESDAY MORNING...WINDS AT 850-925MB BECOME SOMEWHAT MISALIGNED
WITH THE SURFACE WINDS...WHICH IS TYPICALLY LESS SUITABLE FOR MORE
STRUCTURED BANDS. THOUGH INVERSION HEIGHTS ARE HIGHER WITH COLDER
850MB TEMPS...GENERALLY UP TO 6-8KFT...THE DGZ IS LOW AND SO EXPECT
THE SAME SMALL SIZED FLAKES-AND LOW ACCUMULATIONS LIKE THOSE
OBSERVED ACROSS UPPER MI ALL WEEK/DESPITE SIMILAR INVERSION HEIGHTS.
THE NAM HINTS AT SOME HIGHER SNOW RATIOS OCCURRING IN THE
EAST...HOWEVER...THE NAM HAS BEEN TRENDING HIGHER THROUGH THIS PAST
WEEK THAN WHAT IS BEING OBSERVED. OVERALL...WEVE SEEN AROUND 18-20:1
RATIOS...AND THIS IS WHAT WAS USED FOR THE FORECAST. USING THE
NAM...THE BEST LIFT COLLOCATED WITH THE DGZ IS BETWEEN 6Z AND 15Z
WEDNESDAY AROUND MUNISING...AND SOME BIGGER FLAKES MAY BE SEEN
DURING THIS TIME. OTHERWISE...EXPECT ACCUMULATIONS TO RANGE FROM 1-3
INCHES NEAR THE LAKE FROM 6Z WEDNESDAY TO 12Z THURSDAY.
FRIDAY INTO SATURDAY LOW PRESSURE SLIDING OVER THE CANADIAN PRAIRIE
WILL SWING WINDS AROUND TO THE SOUTH ACROSS UPPER MI...PUSHING ALL
LAKE EFFECT SNOW BANDS OFF INTO LAKE SUPERIOR. 850MB TEMPS WARM AS
WELL...WITH THE ECMWF HINTING AT -8C TO -10C FOR BOTH DAYS. THE COLD
FRONT PASSES ON SATURDAY NIGHT. THE ARCTIC PUSH BEHIND THIS TROUGH
IS NOT TOO BAD...AS TEMPS 850MB TEMPS ARE SOMEWHAT RESCUED BY A
BRIEF RIDGE MOVING FROM THE NORTHERN PLAINS INTO THE GREAT LAKES
THROUGH SUNDAY AFTERNOON. KEPT BROAD CHANCE POPS ACROSS THE CWA FOR
MUCH OF THE FORECAST AREA THROUGH SATURDAY NIGHT. ON SUNDAY...TEMPS
ARE COLD ENOUGH AND WINDS OUT OF THE WEST-NORTHWEST...SO KEPT CHANCE
POPS CONFINED TO LAKE SUPERIOR.
THE MAIN DIFFERENCES BETWEEN MODELS LIE ON MONDAY...WITH THE ECMWF
AND THE GFS BOTH HINTING AT A VERY COLD ARCTIC PUSH OF AIR SLIDING
THROUGH...WITH 850MB TEMPS AS LOW AS -35C OVER UPPER MI. THOUGH THE
GFS IS NOT QUITE AS LOW...IT HAS 850MB TEMPS AT -25C TO -30C FOR THE
AREA. WILL TREND LOWER WITH TEMPS DURING THIS TIME PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1223 PM EST MON DEC 30 2013
KIWD...A DISTURBANCE MOVING THROUGH WISCONSIN WILL LEAD TO
INCREASING MID LEVEL CLOUDS THIS AFTERNOON. BEHIND THE DISTURBANCE
WINDS WILL SHIFT BACK OFF LAKE SUPERIOR AND LEAD TO LAKE EFFECT
SNOW SHOWERS. HAVE KEPT THINGS AT MVFR AT THIS TIME...SINCE THE
BEST CONVERGENCE AND STRONGEST BAND WILL LIKELY STAY NORTH OF THE
TAF SITE.
KCMX...MAIN QUESTION IS IF THE BAND CURRENTLY OVER THE SITE WILL
MOVE NORTH AND BRING A SHORT PERIOD OF MVFR AND MAYBE VFR
CONDITIONS. BASED OFF CURRENT RADAR/SATELLITE TRENDS...THAT IDEA
SEEMS REASONABLE AND HAVE TRENDED TAF TOWARDS THAT. THAT WILL BE
SHORT LIVED...AS NORTHWEST WINDS WILL PUSH THE BAND BACK SOUTH
EARLY THIS EVENING AND LEAD TO ALTERNATE LANDING MINS FOR MUCH OF
THE REST OF THE PERIOD.
KSAW...VFR CONDITIONS SHOULD PREVAIL THROUGH MUCH OF THE PERIOD
WITH THE DISTURBANCE SOUTH OF THE AREA AND UNFAVORABLE WINDS FOR
LAKE EFFECT. WINDS VEER AROUND TO MORE OF A NORTHWEST DIRECTION
OVERNIGHT INTO TUESDAY MORNING...WHICH WILL BRING CLOUDS ON THE LOW
END OF VFR.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 430 PM EST MON DEC 30 2013
WEST-NORTHWEST WINDS WILL VEER TO THE NORTHWEST TONIGHT AND BE IN
THE 15-25KT RANGE. THERE COULD BE SOME GUSTS TO 30KTS OVER THE
EASTERN LAKE AS A MESO-LOW DEVELOPS. THESE WINDS WILL CONTINUE TO
PRODUCE SOME AREAS OF HEAVY FREEZING SPRAY AND WILL CONTINUE THE
HEAVY FREEZING SPRAY WARNING INTO WEDNESDAY MORNING OVER THE EAST.
OTHERWISE...LIGHTER WINDS ARE EXPECTED WEDNESDAY AND THURSDAY
BEFORE AN INCREASE OUT OF THE SOUTHWEST ON FRIDAY AND FRIDAY NIGHT.
THERE COULD BE A FEW GALE FORCE GUSTS TO 35KTS WHEN THIS OCCURS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL ADVISORY UNTIL 11 AM EST /10 AM CST/ TUESDAY FOR
MIZ002-004-005-009>011-084.
LAKE EFFECT SNOW ADVISORY FROM 10 PM THIS EVENING TO 7 PM EST
TUESDAY FOR MIZ006-007-085.
LAKE EFFECT SNOW WARNING UNTIL 7 AM EST TUESDAY FOR MIZ003.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST WEDNESDAY FOR LSZ266.
HEAVY FREEZING SPRAY WARNING FROM 6 AM TUESDAY TO 4 AM EST
WEDNESDAY FOR LSZ248-265.
HEAVY FREEZING SPRAY WARNING FROM 10 PM THIS EVENING TO 1 AM EST
WEDNESDAY FOR LSZ243-244-264.
HEAVY FREEZING SPRAY WARNING FROM 10 PM EST /9 PM CST/ THIS
EVENING TO 10 PM EST /9 PM CST/ TUESDAY FOR LSZ241-242-263.
HEAVY FREEZING SPRAY WARNING FROM 10 PM THIS EVENING TO 4 AM EST
WEDNESDAY FOR LSZ249-250.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...KC
SHORT TERM...SRF
LONG TERM...MCD
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
431 PM EST MON DEC 30 2013
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 430 PM EST MON DEC 30 2013
MOST OF UPPER MICHIGAN IS QUIET BUT COLD THIS AFTERNOON...AS THE
AREA IS UNDER LINGERING AFFECTS OF THE HIGH PRESSURE RIDGE THAT
MOVED THROUGH LAST NIGHT INTO THIS MORNING. THIS HAS LED TO WINDS
BACKING TO THE WEST-SOUTHWEST IN THE BOUNDARY LAYER AND FOCUSED THE
REMAINING LAKE EFFECT OVER THE KEWEENAW AND RIGHT ALONG THE
SHORELINE NEAR GRAND MARAIS. CALLS TO THE KEWEENAW THIS AFTERNOON
INDICATE THAT THE FINE FLAKE LES IS STILL IN PLACE. WHILE THIS IS
GOOD AT REDUCING VISIBILITIES...ACCUMULATIONS HAVE BEEN LIGHT AND
UNDER A COUPLE INCHES. OVER THE WEST...TEMPERATURES HAVE STRUGGLE
TO EVEN REACH ZERO DEGREES THIS AFTERNOON...WHICH WILL PAVE THE WAY
FOR ANOTHER NIGHT WILL COLD WIND CHILLS. FARTHER TO THE
SOUTHWEST...A SHORTWAVE IS SLIDING EAST-SOUTHEAST THROUGH MINNESOTA
AT THIS TIME AND IS LEADING TO LIGHT SNOW SHOWERS. THESE -SHSN
SHOULD MISS MUCH OF THE AREA...BUT COULD LEAD TO A FEW FLURRIES
ALONG THE WISCONSIN BORDER.
A WEAK SURFACE TROUGH OVER CENTRAL/SOUTHERN LAKE SUPERIOR AT THIS
TIME WILL BE THE FOCUS FOR THE LAKE EFFECT TONIGHT INTO TUESDAY
MORNING. ALL THE HIGH RESOLUTION MODELS SHOW A MESO-LOW DEVELOPING
OVER THE SOUTHEASTERN LAKE THIS EVENING. A LOOK AT THE MONTREAL
RIVER RADAR THIS AFTERNOON DOESN/T INDICATE ANY CIRCULATION AT THIS
POINT...BUT IT SHOULD BE DEVELOPING THIS EVENING. IN ADDITION...THE
LAKE EFFECT SNOW WILL BE ENHANCED BY A SHORTWAVE MOVING THROUGH THIS
EVENING. THIS WAVE PROVIDES A LITTLE MORE MOISTURE AND MID LEVEL
UPWARD MOTION...ALONG WITH COOLING ALOFT TO WEAKEN THE INVERSION
CURRENTLY AROUND 6-8KFT AND ALLOWS IT TO RISE TO 10-12KFT OVER THE
EASTERN CWA. ALSO...IT HELPS INTENSIFY THE SURFACE TROUGH OR
MESO-LOW OVER THE EASTERN LAKE BEFORE IT SLIDES SOUTHEAST LATE
TONIGHT INTO TUESDAY MORNING (BUT STILL LEAVES A TROUGH OVER THE
EASTERN LAKE). SINCE THIS HAS BEEN SHOWN FOR SEVERAL DAYS
NOW...FAIRLY CONFIDENT ON ITS OCCURRENCE...THE QUESTION COMES DOWN
TO EXACT LOCATION OF THE HEAVIEST BAND AND WHAT THE SNOW RATIOS WILL
BE. LATEST TRENDS IN THE MODELS SHOW A SLIGHTLY LATER ARRIVAL OF
THE STRONG LES BAND ON THE WEST SIDE OF THE MESO-LOW...LIKELY
CLOSER TO 04-06Z. UNFORTUNATELY THE LOCATION IS ALL OVER
THE MAP...WITH SOME HAVE IT HITTING PICTURED ROCKS (AND
NEARLY MUNISING - RAP AND A COUPLE 15Z HOPWRF MEMBERS) WHILE OTHERS
THE FAR NORTHEAST PART OF LUCE COUNTY (2.5 AND 10KM REGIONAL GEMS).
OPTED TO FOCUS ON THE MIDDLE GROUND WHICH WAS SIMILAR TO THE
PREVIOUS FORECAST AND HAVE THE STRONG BAND COME ONSHORE AROUND THE
GRAND MARAIS AREA. PINNING DOWN THIS LOCATION WILL MAKE OR BREAK
SNOWFALL AMOUNTS AND THE POTENTIAL OF REACHING WARNING SNOWFALL
AMOUNTS. ONCE THIS BAND COMES ON SHORE EXPECT A TRANSITION TO A
GENERAL NORTHWEST FLOW LES THROUGH THE DAY ON TUESDAY. WITH A
WEAK SURFACE TROUGH LINGERING OVER THE FAR EASTERN LAKE...MODELS
ARE INDICATING SOME ENHANCED CONVERGENCE TO LEAD TO A STRONGER BAND
AFFECTING NORTHERN LUCE COUNTY...ALTHOUGH THERE WILL BE SOME
WAVERING EXPECTED.
AS FOR SNOW RATIOS AND AMOUNTS...ARCTIC AIR MASS WILL LIKELY BE
MODIFIED SOMEWHAT FROM THE CIRCULATION AND MOISTURE/HEAT FLUX OFF
THE LAKE...WHICH WILL TRY TO PUT SOME OF THE CLOUD INTO THE DGZ.
THUS...WOULD EXPECT SOME HIGHER RATIOS TONIGHT AS THE BAND
COMES ON SHORE AND BEFORE SLIGHTLY COOLER AIR ARRIVES ON
TUESDAY AND TRANSITION BACK TO MORE OF A FINER FLAKE SNOW THAT
WE HAVE SEEN THE LAST 24-48HRS. ON TO AMOUNTS...PREVIOUS FORECAST
WAS RIGHT ON THE EDGE OF BOTH 12/24HR AMOUNTS AND HAVE SIMILAR IF
NOT SLIGHTLY LOWER VALUES FOR THIS FORECAST. THINK THERE WILL BE A
GOOD BURST WITH THAT STRONG BAND TONIGHT INTO TUESDAY MORNING OF 3
TO 7 INCHES. THEN THE TRANSITION TO MORE NORTHWEST WINDS AND
SLIGHTLY LOWER RATIOS SHOULD LEAD TO ANOTHER PERIOD OF 2-6 INCHES
FROM MID MORNING INTO THE EARLY EVENING (BUT LIKELY FOCUSED FARTHER
EAST INTO LUCE COUNTY). THIS IS JUST PUTS THE FORECAST JUST UNDER
BOTH THE 12/24HR WARNING AMOUNTS AND WITH THE UNCERTAINTY IN THE
EXACT LOCATION OF THE HEAVIEST SNOW...WILL ISSUE A STRONGLY WORDED
ADVISORY FOR ALGER/LUCE AND NORTHERN SCHOOLCRAFT FOR TONIGHT INTO
TUESDAY. THAT WAY WE CAN HOPEFULLY GET ONE MORE LOOK AT HIGH RES
RUNS AND IF THERE IS A BETTER HANDLE ON LOCATION AND CONFIDENCE
GROWS ON WARNING AMOUNTS...CAN UPGRADE THIS EVENING OR TONIGHT FOR
THE MORE SPECIFIC LOCATION. WITH ALL OF THE LOCATION
DIFFERENCES...WOULD HATE TO ISSUE A WARNING FOR LUCE AND THEN HAVE
IT STAY MAINLY IN ALGER OR VICE-VERSA.
OVER THE WEST...A SURFACE TROUGH STRETCHED WEST ACROSS SOUTHERN
LAKE SUPERIOR WILL SLOWLY PUSH THE MAIN BAND AFFECTING THE KEWEENAW
SOUTH TONIGHT INTO THE ONTONAGON AND SOUTHERN PORTIONS OF HOUGHTON
COUNTY AREA TONIGHT. AS THIS OCCURS...THE REST OF THE KEWEENAW WILL
TRANSITION TO MORE OF A NW FLOW LAKE EFFECT SCENARIO WHICH WILL
CONTINUE INTO TUESDAY. LESS RESIDENCE TIME OVER WESTERN LAKE
SUPERIOR WILL LIMIT THE ARCTIC AIR MASS MODERATION AND SHOULD KEEP
MOST OF THE CLOUD LAYER ABOVE THE DGZ. THUS...WOULD EXPECT THE
SMALLER SNOW FLAKES AND RATIOS TO CONTINUE THERE AND LIMIT
ACCUMULATIONS. INVERSION HEIGHTS ARE GREATER THAN THE PAST 24HRS
(7-9KFT) WHICH WILL LEAD TO SLIGHTLY STRONGER SHOWERS...BUT ALL OF
THAT CLOUD LAYER WILL BE WELL ABOVE THE DGZ. CURRENT THOUGHT IS
THERE BEING AN INCREASE IN SNOW ACCUMULATION THIS EVENING...BEFORE
COLDER 850MB TEMPS MOVE IN BEHIND THE SHORTWAVE (FALLING TO ALMOST
-26C BY 12Z TUESDAY) AND PUSH ALL OF THE CLOUD ABOVE THE DGZ.
ALTHOUGH TOTAL AMOUNTS OVER THE 24 HOUR PERIOD MAY REACH THE 3-6INCH
RANGE...THINK 12HR AMOUNTS WILL BE HARD PRESSED TO REACH THE 4 INCH
AMOUNT NEEDED FOR A LES ADVISORY.
A COLD START TO THE DAY AND A TIGHTENING SURFACE GRADIENT WITH THE
SURFACE DROPPING SOUTH INTO NORTHERN UPPER MICHIGAN TONIGHT WILL
LEAD TO ANOTHER NIGHT OF VERY COLD WIND CHILLS. THINK THE SCATTERED
HIGH CLOUDS AND SLIGHTLY HIGHER WINDS WILL KEEP TEMPS SLIGHTLY
WARMER THAN LAST NIGHT. BUT THIS WILL ALSO KEEP WIND CHILLS LOW AND
SIMILAR TO LAST NIGHT. THEREFORE...HAVE ISSUED A WIND CHILL
ADVISORY FOR THE SAME LOCATIONS AS LAST NIGHT AND HAVE IT RUNNING
THROUGH LATE TUESDAY MORNING. ONCE AGAIN...TEMPERATURES WILL
STRUGGLE TO REBOUND TOMORROW AND SOME LOCATIONS OUT WEST WILL STAY
IN THE SINGLE DIGITS BELOW ZERO.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 430 PM EST MON DEC 30 2013
MODELS ARE CONSISTENT IN SHOWING THE 500MB CLOSED LOW OVER QUEBEC
WEDNESDAY MOVING OFF INTO THE ATLANTIC THURSDAY. THE GFS /AS USUAL/
IS MORE PROGRESSIVE THAN THE ECWMF WITH THE LONGWAVE TROUGH IN THE
WAKE OF THE LOW...BRINGING THE TROUGH THROUGH THE GREAT LAKES ON
THURSDAY AFTERNOON. THE ECMWF IS SLOWER AND DEEPER WITH THIS
TROUGH...WITH IT BEING MAINLY OVER WI ON THURSDAY AFTERNOON.
GUIDANCE SUGGESTS THAT THE ECMWF HAS BEEN ERRING ON THE DEEPER AND
MORE AMPLIFIED SIDE LATELY...HOWEVER...AND THIS MAY BE THE CASE.
OVERALL WENT MIDDLE OF THE ROAD FOR THE FORECAST AT THIS
POINT...LEANING MORE TOWARDS THE ECMWF. AS FAR AS WHAT THIS MEANS
FOR THE SURFACE...LOW PRESSURE DEVELOPS IN THE CENTRAL PLAINS AND
RIDES NORTHEASTWARD ALONG THE TROUGH...WHICH BRINGS AN INVERTED
SURFACE TROUGH INTO UPPER MI FOR WEDNESDAY NIGHT-THURSDAY AFTERNOON.
TUESDAY NIGHT WINDS REMAIN OUT OF THE WEST NORTHWEST THROUGH
MIDNIGHT...BEFORE GRADUALLY VEERING TO THE NORTH AND EVEN NORTHEAST
AS THE INVERTED TROUGH SHIFTS WESTWARD. THIS MOVES THE HIGHEST POPS
FROM THE FAR NORTHEASTERN PORTIONS OF THE COUNTY TOWARDS MUNISING
THROUGH THE NIGHT. BY WEDNESDAY AFTERNOON...CONVERGENCE FOCUSES
BETWEEN MARQUETTE AND MUNISING...WHICH IS WHERE HIGHEST POPS ARE
SITUATED IN THE GRIDS. WHILE THIS REMAINS THE CASE THROUGH THURSDAY
AFTERNOON...TOTAL ACCUMULATIONS ARE GENERALLY EXPECTED TO BE ON THE
ORDER OF 2 TO 4 INCHES BETWEEN SHOT POINT AND MUNISING. GIVEN THAT
MOST OF THE BANDS ARE SHIFTING FROM WEST-NORTHWEST INTO A MORE
NORTH-NORTHEAST PATTERN THROUGH THE PERIOD...NOT REALLY EXPECTING
ANY ONE LOCATION TO RECEIVE TOO MUCH ACCUMULATION. ALSO...BEYOND
WEDNESDAY MORNING...WINDS AT 850-925MB BECOME SOMEWHAT MISALIGNED
WITH THE SURFACE WINDS...WHICH IS TYPICALLY LESS SUITABLE FOR MORE
STRUCTURED BANDS. THOUGH INVERSION HEIGHTS ARE HIGHER WITH COLDER
850MB TEMPS...GENERALLY UP TO 6-8KFT...THE DGZ IS LOW AND SO EXPECT
THE SAME SMALL SIZED FLAKES-AND LOW ACCUMULATIONS LIKE THOSE
OBSERVED ACROSS UPPER MI ALL WEEK/DESPITE SIMILAR INVERSION HEIGHTS.
THE NAM HINTS AT SOME HIGHER SNOW RATIOS OCCURRING IN THE
EAST...HOWEVER...THE NAM HAS BEEN TRENDING HIGHER THROUGH THIS PAST
WEEK THAN WHAT IS BEING OBSERVED. OVERALL...WEVE SEEN AROUND 18-20:1
RATIOS...AND THIS IS WHAT WAS USED FOR THE FORECAST. USING THE
NAM...THE BEST LIFT COLLOCATED WITH THE DGZ IS BETWEEN 6Z AND 15Z
WEDNESDAY AROUND MUNISING...AND SOME BIGGER FLAKES MAY BE SEEN
DURING THIS TIME. OTHERWISE...EXPECT ACCUMULATIONS TO RANGE FROM 1-3
INCHES NEAR THE LAKE FROM 6Z WEDNESDAY TO 12Z THURSDAY.
FRIDAY INTO SATURDAY LOW PRESSURE SLIDING OVER THE CANADIAN PRAIRIE
WILL SWING WINDS AROUND TO THE SOUTH ACROSS UPPER MI...PUSHING ALL
LAKE EFFECT SNOW BANDS OFF INTO LAKE SUPERIOR. 850MB TEMPS WARM AS
WELL...WITH THE ECMWF HINTING AT -8C TO -10C FOR BOTH DAYS. THE COLD
FRONT PASSES ON SATURDAY NIGHT. THE ARCTIC PUSH BEHIND THIS TROUGH
IS NOT TOO BAD...AS TEMPS 850MB TEMPS ARE SOMEWHAT RESCUED BY A
BRIEF RIDGE MOVING FROM THE NORTHERN PLAINS INTO THE GREAT LAKES
THROUGH SUNDAY AFTERNOON. KEPT BROAD CHANCE POPS ACROSS THE CWA FOR
MUCH OF THE FORECAST AREA THROUGH SATURDAY NIGHT. ON SUNDAY...TEMPS
ARE COLD ENOUGH AND WINDS OUT OF THE WEST-NORTHWEST...SO KEPT CHANCE
POPS CONFINED TO LAKE SUPERIOR.
THE MAIN DIFFERENCES BETWEEN MODELS LIE ON MONDAY...WITH THE ECMWF
AND THE GFS BOTH HINTING AT A VERY COLD ARCTIC PUSH OF AIR SLIDING
THROUGH...WITH 850MB TEMPS AS LOW AS -35C OVER UPPER MI. THOUGH THE
GFS IS NOT QUITE AS LOW...IT HAS 850MB TEMPS AT -25C TO -30C FOR THE
AREA. WILL TREND LOWER WITH TEMPS DURING THIS TIME PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1223 PM EST MON DEC 30 2013
KIWD...A DISTURBANCE MOVING THROUGH WISCONSIN WILL LEAD TO
INCREASING MID LEVEL CLOUDS THIS AFTERNOON. BEHIND THE DISTURBANCE
WINDS WILL SHIFT BACK OFF LAKE SUPERIOR AND LEAD TO LAKE EFFECT
SNOW SHOWERS. HAVE KEPT THINGS AT MVFR AT THIS TIME...SINCE THE
BEST CONVERGENCE AND STRONGEST BAND WILL LIKELY STAY NORTH OF THE
TAF SITE.
KCMX...MAIN QUESTION IS IF THE BAND CURRENTLY OVER THE SITE WILL
MOVE NORTH AND BRING A SHORT PERIOD OF MVFR AND MAYBE VFR
CONDITIONS. BASED OFF CURRENT RADAR/SATELLITE TRENDS...THAT IDEA
SEEMS REASONABLE AND HAVE TRENDED TAF TOWARDS THAT. THAT WILL BE
SHORT LIVED...AS NORTHWEST WINDS WILL PUSH THE BAND BACK SOUTH
EARLY THIS EVENING AND LEAD TO ALTERNATE LANDING MINS FOR MUCH OF
THE REST OF THE PERIOD.
KSAW...VFR CONDITIONS SHOULD PREVAIL THROUGH MUCH OF THE PERIOD
WITH THE DISTURBANCE SOUTH OF THE AREA AND UNFAVORABLE WINDS FOR
LAKE EFFECT. WINDS VEER AROUND TO MORE OF A NORTHWEST DIRECTION
OVERNIGHT INTO TUESDAY MORNING...WHICH WILL BRING CLOUDS ON THE LOW
END OF VFR.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 430 PM EST MON DEC 30 2013
WEST-NORTHWEST WINDS WILL VEER TO THE NORTHWEST TONIGHT AND BE IN
THE 15-25KT RANGE. THERE COULD BE SOME GUSTS TO 30KTS OVER THE
EASTERN LAKE AS A MESO-LOW DEVELOPS. THESE WINDS WILL CONTINUE TO
PRODUCE SOME AREAS OF HEAVY FREEZING SPRAY AND WILL CONTINUE THE
HEAVY FREEZING SPRAY WARNING INTO WEDNESDAY MORNING OVER THE EAST.
OTHERWISE...LIGHTER WINDS ARE EXPECTED WEDNESDAY AND THURSDAY
BEFORE AN INCREASE OUT OF THE SOUTHWEST ON FRIDAY AND FRIDAY NIGHT.
THERE COULD BE A FEW GALE FORCE GUSTS TO 35KTS WHEN THIS OCCURS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY FROM 10 PM THIS EVENING TO 7 PM EST
TUESDAY FOR MIZ006-007-085.
WIND CHILL ADVISORY FROM 8 PM EST /7 PM CST/ THIS EVENING TO 11
AM EST /10 AM CST/ TUESDAY FOR MIZ002-004-005-009>011-084.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST WEDNESDAY FOR LSZ266.
HEAVY FREEZING SPRAY WARNING FROM 6 AM TUESDAY TO 4 AM EST
WEDNESDAY FOR LSZ248-265.
HEAVY FREEZING SPRAY WARNING FROM 10 PM THIS EVENING TO 1 AM EST
WEDNESDAY FOR LSZ243-244-264.
HEAVY FREEZING SPRAY WARNING FROM 10 PM EST /9 PM CST/ THIS
EVENING TO 10 PM EST /9 PM CST/ TUESDAY FOR LSZ241-242-263.
HEAVY FREEZING SPRAY WARNING FROM 10 PM THIS EVENING TO 4 AM EST
WEDNESDAY FOR LSZ249-250.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...MCD
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
418 PM EST MON DEC 30 2013
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 417 PM EST MON DEC 30 2013
MOST OF UPPER MICHIGAN IS QUIET BUT COLD THIS AFTERNOON...AS THE
AREA IS UNDER LINGERING AFFECTS OF THE HIGH PRESSURE RIDGE THAT
MOVED THROUGH LAST NIGHT INTO THIS MORNING. THIS HAS LED TO WINDS
BACKING TO THE WEST-SOUTHWEST IN THE BOUNDARY LAYER AND FOCUSED THE
REMAINING LAKE EFFECT OVER THE KEWEENAW AND RIGHT ALONG THE
SHORELINE NEAR GRAND MARAIS. CALLS TO THE KEWEENAW THIS AFTERNOON
INDICATE THAT THE FINE FLAKE LES IS STILL IN PLACE. WHILE THIS IS
GOOD AT REDUCING VISIBILITIES...ACCUMULATIONS HAVE BEEN LIGHT AND
UNDER A COUPLE INCHES. OVER THE WEST...TEMPERATURES HAVE STRUGGLE
TO EVEN REACH ZERO DEGREES THIS AFTERNOON...WHICH WILL PAVE THE WAY
FOR ANOTHER NIGHT WILL COLD WIND CHILLS. FARTHER TO THE
SOUTHWEST...A SHORTWAVE IS SLIDING EAST-SOUTHEAST THROUGH MINNESOTA
AT THIS TIME AND IS LEADING TO LIGHT SNOW SHOWERS. THESE -SHSN
SHOULD MISS MUCH OF THE AREA...BUT COULD LEAD TO A FEW FLURRIES
ALONG THE WISCONSIN BORDER.
A WEAK SURFACE TROUGH OVER CENTRAL/SOUTHERN LAKE SUPERIOR AT THIS
TIME WILL BE THE FOCUS FOR THE LAKE EFFECT TONIGHT INTO TUESDAY
MORNING. ALL THE HIGH RESOLUTION MODELS SHOW A MESO-LOW DEVELOPING
OVER THE SOUTHEASTERN LAKE THIS EVENING. A LOOK AT THE MONTREAL
RIVER RADAR THIS AFTERNOON DOESN/T INDICATE ANY CIRCULATION AT THIS
POINT...BUT IT SHOULD BE DEVELOPING THIS EVENING. IN ADDITION...THE
LAKE EFFECT SNOW WILL BE ENHANCED BY A SHORTWAVE MOVING THROUGH THIS
EVENING. THIS WAVE PROVIDES A LITTLE MORE MOISTURE AND MID LEVEL
UPWARD MOTION...ALONG WITH COOLING ALOFT TO WEAKEN THE INVERSION
CURRENTLY AROUND 6-8KFT AND ALLOWS IT TO RISE TO 10-12KFT OVER THE
EASTERN CWA. ALSO...IT HELPS INTENSIFY THE SURFACE TROUGH OR
MESO-LOW OVER THE EASTERN LAKE BEFORE IT SLIDES SOUTHEAST LATE
TONIGHT INTO TUESDAY MORNING (BUT STILL LEAVES A TROUGH OVER THE
EASTERN LAKE). SINCE THIS HAS BEEN SHOWN FOR SEVERAL DAYS
NOW...FAIRLY CONFIDENT ON ITS OCCURRENCE...THE QUESTION COMES DOWN
TO EXACT LOCATION OF THE HEAVIEST BAND AND WHAT THE SNOW RATIOS WILL
BE. LATEST TRENDS IN THE MODELS SHOW A SLIGHTLY LATER ARRIVAL OF
THE STRONG LES BAND ON THE WEST SIDE OF THE MESO-LOW...LIKELY
CLOSER TO 04-06Z. UNFORTUNATELY THE LOCATION IS ALL OVER
THE MAP...WITH SOME HAVE IT HITTING PICTURED ROCKS (AND
NEARLY MUNISING - RAP AND A COUPLE 15Z HOPWRF MEMBERS) WHILE OTHERS
THE FAR NORTHEAST PART OF LUCE COUNTY (2.5 AND 10KM REGIONAL GEMS).
OPTED TO FOCUS ON THE MIDDLE GROUND WHICH WAS SIMILAR TO THE
PREVIOUS FORECAST AND HAVE THE STRONG BAND COME ONSHORE AROUND THE
GRAND MARAIS AREA. PINNING DOWN THIS LOCATION WILL MAKE OR BREAK
SNOWFALL AMOUNTS AND THE POTENTIAL OF REACHING WARNING SNOWFALL
AMOUNTS. ONCE THIS BAND COMES ON SHORE EXPECT A TRANSITION TO A
GENERAL NORTHWEST FLOW LES THROUGH THE DAY ON TUESDAY. WITH A
WEAK SURFACE TROUGH LINGERING OVER THE FAR EASTERN LAKE...MODELS
ARE INDICATING SOME ENHANCED CONVERGENCE TO LEAD TO A STRONGER BAND
AFFECTING NORTHERN LUCE COUNTY...ALTHOUGH THERE WILL BE SOME
WAVERING EXPECTED.
AS FOR SNOW RATIOS AND AMOUNTS...ARCTIC AIR MASS WILL LIKELY BE
MODIFIED SOMEWHAT FROM THE CIRCULATION AND MOISTURE/HEAT FLUX OFF
THE LAKE...WHICH WILL TRY TO PUT SOME OF THE CLOUD INTO THE DGZ.
THUS...WOULD EXPECT SOME HIGHER RATIOS TONIGHT AS THE BAND
COMES ON SHORE AND BEFORE SLIGHTLY COOLER AIR ARRIVES ON
TUESDAY AND TRANSITION BACK TO MORE OF A FINER FLAKE SNOW THAT
WE HAVE SEEN THE LAST 24-48HRS. ON TO AMOUNTS...PREVIOUS FORECAST
WAS RIGHT ON THE EDGE OF BOTH 12/24HR AMOUNTS AND HAVE SIMILAR IF
NOT SLIGHTLY LOWER VALUES FOR THIS FORECAST. THINK THERE WILL BE A
GOOD BURST WITH THAT STRONG BAND TONIGHT INTO TUESDAY MORNING OF 3
TO 7 INCHES. THEN THE TRANSITION TO MORE NORTHWEST WINDS AND
SLIGHTLY LOWER RATIOS SHOULD LEAD TO ANOTHER PERIOD OF 2-6 INCHES
FROM MID MORNING INTO THE EARLY EVENING (BUT LIKELY FOCUSED FARTHER
EAST INTO LUCE COUNTY). THIS IS JUST PUTS THE FORECAST JUST UNDER
BOTH THE 12/24HR WARNING AMOUNTS AND WITH THE UNCERTAINTY IN THE
EXACT LOCATION OF THE HEAVIEST SNOW...WILL ISSUE A STRONGLY WORDED
ADVISORY FOR ALGER/LUCE AND NORTHERN SCHOOLCRAFT FOR TONIGHT INTO
TUESDAY. THAT WAY WE CAN HOPEFULLY GET ONE MORE LOOK AT HIGH RES
RUNS AND IF THERE IS A BETTER HANDLE ON LOCATION AND CONFIDENCE
GROWS ON WARNING AMOUNTS...CAN UPGRADE THIS EVENING OR TONIGHT FOR
THE MORE SPECIFIC LOCATION. WITH ALL OF THE LOCATION
DIFFERENCES...WOULD HATE TO ISSUE A WARNING FOR LUCE AND THEN HAVE
IT STAY MAINLY IN ALGER OR VICE-VERSA.
OVER THE WEST...A SURFACE TROUGH STRETCHED WEST ACROSS SOUTHERN
LAKE SUPERIOR WILL SLOWLY PUSH THE MAIN BAND AFFECTING THE KEWEENAW
SOUTH TONIGHT INTO THE ONTONAGON AND SOUTHERN PORTIONS OF HOUGHTON
COUNTY AREA TONIGHT. AS THIS OCCURS...THE REST OF THE KEWEENAW WILL
TRANSITION TO MORE OF A NW FLOW LAKE EFFECT SCENARIO WHICH WILL
CONTINUE INTO TUESDAY. LESS RESIDENCE TIME OVER WESTERN LAKE
SUPERIOR WILL LIMIT THE ARCTIC AIR MASS MODERATION AND SHOULD KEEP
MOST OF THE CLOUD LAYER ABOVE THE DGZ. THUS...WOULD EXPECT THE
SMALLER SNOW FLAKES AND RATIOS TO CONTINUE THERE AND LIMIT
ACCUMULATIONS. INVERSION HEIGHTS ARE GREATER THAN THE PAST 24HRS
(7-9KFT) WHICH WILL LEAD TO SLIGHTLY STRONGER SHOWERS...BUT ALL OF
THAT CLOUD LAYER WILL BE WELL ABOVE THE DGZ. CURRENT THOUGHT IS
THERE BEING AN INCREASE IN SNOW ACCUMULATION THIS EVENING...BEFORE
COLDER 850MB TEMPS MOVE IN BEHIND THE SHORTWAVE (FALLING TO ALMOST
-26C BY 12Z TUESDAY) AND PUSH ALL OF THE CLOUD ABOVE THE DGZ.
ALTHOUGH TOTAL AMOUNTS OVER THE 24 HOUR PERIOD MAY REACH THE 3-6INCH
RANGE...THINK 12HR AMOUNTS WILL BE HARD PRESSED TO REACH THE 4 INCH
AMOUNT NEEDED FOR A LES ADVISORY.
A COLD START TO THE DAY AND A TIGHTENING SURFACE GRADIENT WITH THE
SURFACE DROPPING SOUTH INTO NORTHERN UPPER MICHIGAN TONIGHT WILL
LEAD TO ANOTHER NIGHT OF VERY COLD WIND CHILLS. THINK THE SCATTERED
HIGH CLOUDS AND SLIGHTLY HIGHER WINDS WILL KEEP TEMPS SLIGHTLY
WARMER THAN LAST NIGHT. BUT THIS WILL ALSO KEEP WIND CHILLS LOW AND
SIMILAR TO LAST NIGHT. THEREFORE...HAVE ISSUED A WIND CHILL
ADVISORY FOR THE SAME LOCATIONS AS LAST NIGHT AND HAVE IT RUNNING
THROUGH LATE TUESDAY MORNING. ONCE AGAIN...TEMPERATURES WILL
STRUGGLE TO REBOUND TOMORROW AND SOME LOCATIONS OUT WEST WILL STAY
IN THE SINGLE DIGITS BELOW ZERO.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 506 AM EST MON DEC 30 2013
TAKING A LOOK AT THE LARGE SCALE PATTERN...THE UPPER GREAT LAKES
WILL REMAIN DOMINATED BY A TROUGH AT 500MB THROUGH THURSDAY. EVEN
WHEN THE MAIN 500MB LOW DOES EXIT OFF THE NE CANADIAN COAST ON
SATURDAY...ANOTHER LOW SITUATED OVER N CENTRAL CANADA FRIDAY NIGHT
LOOKS TO DIVE ACROSS S CENTRAL CANADA FOR THE LATTER HALF OF THE
WEEKEND. THE ONLY DAYS WHERE THE MERCURY MAY RISE AT OR ABOVE 20F
LOOKS TO BE SATURDAY...AND TO A LESSER EXTENT SUNDAY.
VERY COLD TUESDAY NIGHT...
GIVEN THE COLD AIR LOCKED IN PLACE...ANY MODERATE OR STRONG WINDS
WILL RESULT IN DANGEROUS WIND CHILLS. WIND CHILL VALUES WILL LIKELY
FALL TO THESE DANGEROUS VALUES TUESDAY NIGHT AS STRONG/COLD HIGH
PRESSURE SURGES IN AGAIN FROM THE NW. HOWEVER...WITH WINDS IN THE
COLDEST LOCATIONS LESS THAN OUR 10MPH WIND CHILL ADVISORY/WARNING
CRITERIA...HEADLINES MAY NOT BE POSTED /ALTHOUGH NAM GUIDANCE IS
NEAR/. WE WILL CONTINUE TO HIGHLIGHT THE DANGER HERE...IN THE
HWO...AND WITH SOCIAL MEDIA. THE GFS-MOS CAME IN WITH A FCST LOW OF
-22F AT CHAMPION/VAN RIPER...WITH -17F AT BOTH BERGLAND DAM AND IWD.
CONTINUED LAKE EFFECT SNOW SHOWERS THROUGH THURSDAY...MODERATE TO
HEAVY LES MAY BE ONGOING FOR MAINLY E ALGER/N SCHOOLCRAFT/N LUCE
COUNTIES TUESDAY MORNING. CONTINUED NW FLOW ON COLD AIR AVERAGING
-20 TO -23C AT 850MB WILL BE THE RULE UNTIL APPROX 6Z WEDNESDAY WHEN
THE WINDS BECOME DISRUPTED AS THE SFC TROUGH/LOW STUCK OVER SE LAKE
SUPERIOR WEAKENS AND BECOMES ABSORBED BY THE HIGH SET UP TO OUR NW.
WITH A MESO-LOW LIKELY DEVELOPING IT WILL BE DIFFICULT TO PIN POINT
WHERE AND FOR HOW LONG A DOMINANT BAND OF SNOW MAY
DEVELOP...ANYWHERE FROM NEAR MUNISING TO EAST OF GRAND MARAIS. WILL
WAIT FOR NEAR TERM MODELS TO COME INTO BETTER AGREEMENT BEFORE
REDUCING WATCH TO ADVISORIES...OR HOISTING LES WARNINGS FOR ALGER
AND LUCE COUNTIES.
LES WILL CONTINUE WEDNESDAY INTO THURSDAY...MAINLY ON THE N AND NE
SNOWBELTS. LATEST GUIDANCE INDICATES THE POTENTIAL FOR 3-8IN OF SNOW
ACROSS THE HURON MOUNTAINS FROM LATE WEDNESDAY MORNING THROUGH EARLY
THURSDAY MORNING. HEADLINES MAY BE NEEDED AS THE TIME NEARS.
WARMER AIR THIS WEEKEND...
AS NOTED PREVIOUSLY A SURGE OF RELATIVELY WARM AIR IS FIGURED FOR
THE UPCOMING WEEKEND. THE 30/00Z RUN OF THE GFS INCREASED THE 850MB
WINDS BY APPROX 5-10KTS...WITH THE ECMWF AND GFS SHOWING BETWEEN 40
AND 65KT SW TO W LLJ FROM ROUGHLY 00-18Z SATURDAY. THIS WILL ALLOW
850MB TEMPS TO RISE UP TO -4 TO -8C. AHEAD OF THE SFC LOW SET UP
FROM THE PLAINS STATES THROUGH W ONTARIO...RISING OVERNIGHT TEMPS
WILL BE LIKELY FRIDAY NIGHT INTO SATURDAY. THERE OF COURSE ARE SOME
TIMING DIFFERENCES...WITH THE LOW AND ITS ASSOCIATED COLD FRONT
BEING 6-12HRS QUICK OFF THE LATEST GFS. THE SLOWER ECMWF SOLUTION IS
BACKED UP AT LEAST EARLY SATURDAY BY THE CANADIAN AND DGEX.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1223 PM EST MON DEC 30 2013
KIWD...A DISTURBANCE MOVING THROUGH WISCONSIN WILL LEAD TO
INCREASING MID LEVEL CLOUDS THIS AFTERNOON. BEHIND THE DISTURBANCE
WINDS WILL SHIFT BACK OFF LAKE SUPERIOR AND LEAD TO LAKE EFFECT
SNOW SHOWERS. HAVE KEPT THINGS AT MVFR AT THIS TIME...SINCE THE
BEST CONVERGENCE AND STRONGEST BAND WILL LIKELY STAY NORTH OF THE
TAF SITE.
KCMX...MAIN QUESTION IS IF THE BAND CURRENTLY OVER THE SITE WILL
MOVE NORTH AND BRING A SHORT PERIOD OF MVFR AND MAYBE VFR
CONDITIONS. BASED OFF CURRENT RADAR/SATELLITE TRENDS...THAT IDEA
SEEMS REASONABLE AND HAVE TRENDED TAF TOWARDS THAT. THAT WILL BE
SHORT LIVED...AS NORTHWEST WINDS WILL PUSH THE BAND BACK SOUTH
EARLY THIS EVENING AND LEAD TO ALTERNATE LANDING MINS FOR MUCH OF
THE REST OF THE PERIOD.
KSAW...VFR CONDITIONS SHOULD PREVAIL THROUGH MUCH OF THE PERIOD
WITH THE DISTURBANCE SOUTH OF THE AREA AND UNFAVORABLE WINDS FOR
LAKE EFFECT. WINDS VEER AROUND TO MORE OF A NORTHWEST DIRECTION
OVERNIGHT INTO TUESDAY MORNING...WHICH WILL BRING CLOUDS ON THE LOW
END OF VFR.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 417 PM EST MON DEC 30 2013
WEST-NORTHWEST WINDS WILL VEER TO THE NORTHWEST TONIGHT AND BE IN
THE 15-25KT RANGE. THERE COULD BE SOME GUSTS TO 30KTS OVER THE
EASTERN LAKE AS A MESO-LOW DEVELOPS. THESE WINDS WILL CONTINUE TO
PRODUCE SOME AREAS OF HEAVY FREEZING SPRAY AND WILL CONTINUE THE
HEAVY FREEZING SPRAY WARNING INTO WEDNESDAY MORNING OVER THE EAST.
OTHERWISE...LIGHTER WINDS ARE EXPECTED WEDNESDAY AND THURSDAY
BEFORE AN INCREASE OUT OF THE SOUTHWEST ON FRIDAY AND FRIDAY NIGHT.
THERE COULD BE A FEW GALE FORCE GUSTS TO 35KTS WHEN THIS OCCURS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY FROM 10 PM THIS EVENING TO 7 PM EST
TUESDAY FOR MIZ006-007-085.
WIND CHILL ADVISORY FROM 8 PM EST /7 PM CST/ THIS EVENING TO 11
AM EST /10 AM CST/ TUESDAY FOR MIZ002-004-005-009>011-084.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST WEDNESDAY FOR LSZ266.
HEAVY FREEZING SPRAY WARNING FROM 6 AM TUESDAY TO 4 AM EST
WEDNESDAY FOR LSZ248-265.
HEAVY FREEZING SPRAY WARNING FROM 10 PM THIS EVENING TO 1 AM EST
WEDNESDAY FOR LSZ243-244-264.
HEAVY FREEZING SPRAY WARNING FROM 10 PM EST /9 PM CST/ THIS
EVENING TO 10 PM EST /9 PM CST/ TUESDAY FOR LSZ241-242-263.
HEAVY FREEZING SPRAY WARNING FROM 10 PM THIS EVENING TO 4 AM EST
WEDNESDAY FOR LSZ249-250.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...KF
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1225 PM EST MON DEC 30 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 540 AM EST MON DEC 30 2013
WV IMAGERY AND RUC ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW FROM
CENTRAL CANADA INTO THE NRN GREAT LAKES AROUND THE POLAR VORTEX OVER
HUDSON BAY. ONE IN A SERIES OF CLIPPER SHORTWAVE TROUGHS OVER THE
NRN PLAINS SUPPORTED AN AREA OF LIGHT SNOW OVER THE DAKOTAS. AT THE
SFC...DIMINISHING WNW WINDS PREVAILED ACROSS THE REGION AHEAD
OF THE ARCTIC HIGH PRES RIDGE EXTENDING FROM NRN ALBERTA INTO THE
UPPER MS VALLEY. RADAR INDICATED WEAK MULTIPLE WIND PARALLEL LES
BANDS INTO UPPER MICHIGAN FROM MUNISING EASTWARD. ALTHOUGH 850 MB
TEMPS REMAINED AROUND -23C...INVERSION HEIGHTS AROUND 5K FT AND THE
VERY DRY UPSTREAM AIRMASS HAS LIMITED LES INTENSITY WITH LIGHT
SNOWFALL RATES OF SMALLER SNOWFLAKES. SATELLITE...SFC OBS AND WEB
CAMS ALSO INDICATED PERSIST LIGHT LES INTO THE WEST. IN AREAS WHERE
SKIES HAD CLEARED...INLAND TEMPS HAVE FALLEN OFF TO -10F TO -20F.
EVEN WITH RELATIVELY LIGHT WINDS OF 5 TO 10 MPH...WIND CHILL VALUES
HAD DROPPED INTO THE ADVISORY (-25 TO -30) RANGE.
TODAY...THE MODELS WERE CONSISTENT IN KEEPING THE LIGHT SNOW
ASSOCIATED WITH THE STRONGER FORCING AND ISENTROPIC LIFT ASSOCIATED
WITH THE SHRTWV SOUTH OF UPPER MI. HOWEVER...THE SHRTWV WILL BRING
BACKING WINDS TOWARD WRLY THAT WILL PUSH THE LES OVER THE EAST
OFFSHORE. THE BACKING TREND MAY ALSO RESULT IN ENHANCED LOW LEVEL
CONV IN THE KEWEENAW AND A PERIOD OF SLIGHTLY HEAVIER LES.
OTHERWISE...DIURNAL WARMING SHOULD BRING MODERATING WIND CHILL
VALUES BY MID MORNING. MAINLY JUST HIGH CLOUDS ARE EXPECTED OVER
MUCH OF THE CWA WITH TEMPS CLIMBING TO 0F TO 5F WEST AND CLOSER TO
10F ALONG LAKE SUPERIOR AND EAST.
TONIGHT...WITH A TROUGH ACROSS SRN LAKE SUPERIOR...THE HIGHER RES
MODELS SUGGEST A MESO-LOW MAY DEVELOP OVER THE SE PORTION OF THE LAKE
THAT MAY DROP INTO THE NE CWA EAST OF MUNISING OVERNIGHT AS WINDS
VEER AND INCREASE BEHIND THE SHRTWV. THIS COULD PRODUCE A PERIOD OF
HEAVY SNOW AS STRONGER MOISTURE/HEAT FLUX OFF THE LAKE IN THE CLOSED
CIRCULATION BRING THE DGZ INTO THE CONVECTIVE LAYER WITH POTENTIALLY
INTENSE LES BANDS. HOWEVER...AS EXPECTED WITH MESOSCALE
FEATURES...THERE IS STILL SIGNIFICANT UNCERTAINTY WITH THE
TIMING/LOCATION/DURATION OF ANY HEAVIER SNOW. SO...THE LES WATCH WAS
RETAINED. THE GREATEST ACCUMULATIONS ARE LIKELY FROM PICTURED ROCKS
AND GRAND MARAIS INTO NRN LUCE COUNTY. ALTHOUGH TEMPS ARE NOT
EXPECTED TO DROP AS MUCH TONIGHT WITH GREATER CLOUD COVER...SLIGHTLY
STRONGER WINDS MAY PUSH WIND CHILLS BACK INTO THE ADVISORY RANGE OVER
THE THE INTERIOR WEST HALF.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 506 AM EST MON DEC 30 2013
TAKING A LOOK AT THE LARGE SCALE PATTERN...THE UPPER GREAT LAKES
WILL REMAIN DOMINATED BY A TROUGH AT 500MB THROUGH THURSDAY. EVEN
WHEN THE MAIN 500MB LOW DOES EXIT OFF THE NE CANADIAN COAST ON
SATURDAY...ANOTHER LOW SITUATED OVER N CENTRAL CANADA FRIDAY NIGHT
LOOKS TO DIVE ACROSS S CENTRAL CANADA FOR THE LATTER HALF OF THE
WEEKEND. THE ONLY DAYS WHERE THE MERCURY MAY RISE AT OR ABOVE 20F
LOOKS TO BE SATURDAY...AND TO A LESSER EXTENT SUNDAY.
VERY COLD TUESDAY NIGHT...
GIVEN THE COLD AIR LOCKED IN PLACE...ANY MODERATE OR STRONG WINDS
WILL RESULT IN DANGEROUS WIND CHILLS. WIND CHILL VALUES WILL LIKELY
FALL TO THESE DANGEROUS VALUES TUESDAY NIGHT AS STRONG/COLD HIGH
PRESSURE SURGES IN AGAIN FROM THE NW. HOWEVER...WITH WINDS IN THE
COLDEST LOCATIONS LESS THAN OUR 10MPH WIND CHILL ADVISORY/WARNING
CRITERIA...HEADLINES MAY NOT BE POSTED /ALTHOUGH NAM GUIDANCE IS
NEAR/. WE WILL CONTINUE TO HIGHLIGHT THE DANGER HERE...IN THE
HWO...AND WITH SOCIAL MEDIA. THE GFS-MOS CAME IN WITH A FCST LOW OF
-22F AT CHAMPION/VAN RIPER...WITH -17F AT BOTH BERGLAND DAM AND IWD.
CONTINUED LAKE EFFECT SNOW SHOWERS THROUGH THURSDAY...MODERATE TO
HEAVY LES MAY BE ONGOING FOR MAINLY E ALGER/N SCHOOLCRAFT/N LUCE
COUNTIES TUESDAY MORNING. CONTINUED NW FLOW ON COLD AIR AVERAGING
-20 TO -23C AT 850MB WILL BE THE RULE UNTIL APPROX 6Z WEDNESDAY WHEN
THE WINDS BECOME DISRUPTED AS THE SFC TROUGH/LOW STUCK OVER SE LAKE
SUPERIOR WEAKENS AND BECOMES ABSORBED BY THE HIGH SET UP TO OUR NW.
WITH A MESO-LOW LIKELY DEVELOPING IT WILL BE DIFFICULT TO PIN POINT
WHERE AND FOR HOW LONG A DOMINANT BAND OF SNOW MAY
DEVELOP...ANYWHERE FROM NEAR MUNISING TO EAST OF GRAND MARAIS. WILL
WAIT FOR NEAR TERM MODELS TO COME INTO BETTER AGREEMENT BEFORE
REDUCING WATCH TO ADVISORIES...OR HOISTING LES WARNINGS FOR ALGER
AND LUCE COUNTIES.
LES WILL CONTINUE WEDNESDAY INTO THURSDAY...MAINLY ON THE N AND NE
SNOWBELTS. LATEST GUIDANCE INDICATES THE POTENTIAL FOR 3-8IN OF SNOW
ACROSS THE HURON MOUNTAINS FROM LATE WEDNESDAY MORNING THROUGH EARLY
THURSDAY MORNING. HEADLINES MAY BE NEEDED AS THE TIME NEARS.
WARMER AIR THIS WEEKEND...
AS NOTED PREVIOUSLY A SURGE OF RELATIVELY WARM AIR IS FIGURED FOR
THE UPCOMING WEEKEND. THE 30/00Z RUN OF THE GFS INCREASED THE 850MB
WINDS BY APPROX 5-10KTS...WITH THE ECMWF AND GFS SHOWING BETWEEN 40
AND 65KT SW TO W LLJ FROM ROUGHLY 00-18Z SATURDAY. THIS WILL ALLOW
850MB TEMPS TO RISE UP TO -4 TO -8C. AHEAD OF THE SFC LOW SET UP
FROM THE PLAINS STATES THROUGH W ONTARIO...RISING OVERNIGHT TEMPS
WILL BE LIKELY FRIDAY NIGHT INTO SATURDAY. THERE OF COURSE ARE SOME
TIMING DIFFERENCES...WITH THE LOW AND ITS ASSOCIATED COLD FRONT
BEING 6-12HRS QUICK OFF THE LATEST GFS. THE SLOWER ECMWF SOLUTION IS
BACKED UP AT LEAST EARLY SATURDAY BY THE CANADIAN AND DGEX.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1223 PM EST MON DEC 30 2013
KIWD...A DISTURBANCE MOVING THROUGH WISCONSIN WILL LEAD TO
INCREASING MID LEVEL CLOUDS THIS AFTERNOON. BEHIND THE DISTURBANCE
WINDS WILL SHIFT BACK OFF LAKE SUPERIOR AND LEAD TO LAKE EFFECT
SNOW SHOWERS. HAVE KEPT THINGS AT MVFR AT THIS TIME...SINCE THE
BEST CONVERGENCE AND STRONGEST BAND WILL LIKELY STAY NORTH OF THE
TAF SITE.
KCMX...MAIN QUESTION IS IF THE BAND CURRENTLY OVER THE SITE WILL
MOVE NORTH AND BRING A SHORT PERIOD OF MVFR AND MAYBE VFR
CONDITIONS. BASED OFF CURRENT RADAR/SATELLITE TRENDS...THAT IDEA
SEEMS REASONABLE AND HAVE TRENDED TAF TOWARDS THAT. THAT WILL BE
SHORT LIVED...AS NORTHWEST WINDS WILL PUSH THE BAND BACK SOUTH
EARLY THIS EVENING AND LEAD TO ALTERNATE LANDING MINS FOR MUCH OF
THE REST OF THE PERIOD.
KSAW...VFR CONDITIONS SHOULD PREVAIL THROUGH MUCH OF THE PERIOD
WITH THE DISTURBANCE SOUTH OF THE AREA AND UNFAVORABLE WINDS FOR
LAKE EFFECT. WINDS VEER AROUND TO MORE OF A NORTHWEST DIRECTION
OVERNIGHT INTO TUESDAY MORNING...WHICH WILL BRING CLOUDS ON THE LOW
END OF VFR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 540 AM EST MON DEC 30 2013
WEST NORTHWEST WINDS TO 25 KNOTS ARE EXPECTED TO SLOWLY
DIMINISH...REDUCING THE POTENTIAL FOR FREEZING SPRAY OVER THE LAKE BY
THIS AFTERNOON. AS THE LINGERING SURFACE TROUGH OVER EASTERN LAKE
SUPERIOR STRENGTHENS TONIGHT AND SHIFTS EAST ON
TUESDAY...NORTHWESTERLY WINDS WILL INCREASE WITH SOME GUSTS TO 30KTS
OVER THE EASTERN LAKE TUESDAY AFTERNOON AND EVENING. THIS WILL ALSO
BRING AN INCREASED OPPORTUNITY FOR HEAVY FREEZING SPRAY THROUGH
TUESDAY NIGHT OVER THE EASTERN HALF OF LAKE SUPERIOR. ALTHOUGH THERE
STILL WILL BE A LINGERING TROUGH OVER EASTERN LAKE SUPERIOR INTO
WEDNESDAY...HIGH PRESSURE BUILDING OVER THE UPPER MISSISSIPPI VALLEY
WILL LEAD TO LIGHTER NORTHWESTERLY WINDS FOR WEDNESDAY AND
THURSDAY...BRINGING AN END TO THE POTENTIAL FOR HEAVY FREEZING SPRAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ006-007.
LAKE EFFECT SNOW WATCH FROM 10 PM EST THIS EVENING THROUGH
TUESDAY EVENING FOR MIZ006-007.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST WEDNESDAY FOR LSZ266.
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
LSZ265.
HEAVY FREEZING SPRAY WARNING FROM 10 PM THIS EVENING TO 1 AM EST
WEDNESDAY FOR LSZ264.
HEAVY FREEZING SPRAY WARNING FROM 10 PM THIS EVENING TO 4 AM EST
WEDNESDAY FOR LSZ248>250.
HEAVY FREEZING SPRAY WARNING FROM 10 PM EST /9 PM CST/ THIS
EVENING TO 10 PM EST /9 PM CST/ TUESDAY FOR LSZ241>244.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...SRF
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
644 AM EST MON DEC 30 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 540 AM EST MON DEC 30 2013
WV IMAGERY AND RUC ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW FROM
CENTRAL CANADA INTO THE NRN GREAT LAKES AROUND THE POLAR VORTEX OVER
HUDSON BAY. ONE IN A SERIES OF CLIPPER SHORTWAVE TROUGHS OVER THE
NRN PLAINS SUPPORTED AN AREA OF LIGHT SNOW OVER THE DAKOTAS. AT THE
SFC...DIMINISHING WNW WINDS PREVAILED ACROSS THE REGION AHEAD
OF THE ARCTIC HIGH PRES RIDGE EXTENDING FROM NRN ALBERTA INTO THE
UPPER MS VALLEY. RADAR INDICATED WEAK MULTIPLE WIND PARALLEL LES
BANDS INTO UPPER MICHIGAN FROM MUNISING EASTWARD. ALTHOUGH 850 MB
TEMPS REMAINED AROUND -23C...INVERSION HEIGHTS AROUND 5K FT AND THE
VERY DRY UPSTREAM AIRMASS HAS LIMITED LES INTENSITY WITH LIGHT
SNOWFALL RATES OF SMALLER SNOWFLAKES. SATELLITE...SFC OBS AND WEB
CAMS ALSO INDICATED PERSIST LIGHT LES INTO THE WEST. IN AREAS WHERE
SKIES HAD CLEARED...INLAND TEMPS HAVE FALLEN OFF TO -10F TO -20F.
EVEN WITH RELATIVELY LIGHT WINDS OF 5 TO 10 MPH...WIND CHILL VALUES
HAD DROPPED INTO THE ADVISORY (-25 TO -30) RANGE.
TODAY...THE MODELS WERE CONSISTENT IN KEEPING THE LIGHT SNOW
ASSOCIATED WITH THE STRONGER FORCING AND ISENTROPIC LIFT ASSOCIATED
WITH THE SHRTWV SOUTH OF UPPER MI. HOWEVER...THE SHRTWV WILL BRING
BACKING WINDS TOWARD WRLY THAT WILL PUSH THE LES OVER THE EAST
OFFSHORE. THE BACKING TREND MAY ALSO RESULT IN ENHANCED LOW LEVEL
CONV IN THE KEWEENAW AND A PERIOD OF SLIGHTLY HEAVIER LES.
OTHERWISE...DIURNAL WARMING SHOULD BRING MODERATING WIND CHILL
VALUES BY MID MORNING. MAINLY JUST HIGH CLOUDS ARE EXPECTED OVER
MUCH OF THE CWA WITH TEMPS CLIMBING TO 0F TO 5F WEST AND CLOSER TO
10F ALONG LAKE SUPERIOR AND EAST.
TONIGHT...WITH A TROUGH ACROSS SRN LAKE SUPERIOR...THE HIGHER RES
MODELS SUGGEST A MESO-LOW MAY DEVELOP OVER THE SE PORTION OF THE LAKE
THAT MAY DROP INTO THE NE CWA EAST OF MUNISING OVERNIGHT AS WINDS
VEER AND INCREASE BEHIND THE SHRTWV. THIS COULD PRODUCE A PERIOD OF
HEAVY SNOW AS STRONGER MOISTURE/HEAT FLUX OFF THE LAKE IN THE CLOSED
CIRCULATION BRING THE DGZ INTO THE CONVECTIVE LAYER WITH POTENTIALLY
INTENSE LES BANDS. HOWEVER...AS EXPECTED WITH MESOSCALE
FEATURES...THERE IS STILL SIGNIFICANT UNCERTAINTY WITH THE
TIMING/LOCATION/DURATION OF ANY HEAVIER SNOW. SO...THE LES WATCH WAS
RETAINED. THE GREATEST ACCUMULATIONS ARE LIKELY FROM PICTURED ROCKS
AND GRAND MARAIS INTO NRN LUCE COUNTY. ALTHOUGH TEMPS ARE NOT
EXPECTED TO DROP AS MUCH TONIGHT WITH GREATER CLOUD COVER...SLIGHTLY
STRONGER WINDS MAY PUSH WIND CHILLS BACK INTO THE ADVISORY RANGE OVER
THE THE INTERIOR WEST HALF.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 506 AM EST MON DEC 30 2013
TAKING A LOOK AT THE LARGE SCALE PATTERN...THE UPPER GREAT LAKES
WILL REMAIN DOMINATED BY A TROUGH AT 500MB THROUGH THURSDAY. EVEN
WHEN THE MAIN 500MB LOW DOES EXIT OFF THE NE CANADIAN COAST ON
SATURDAY...ANOTHER LOW SITUATED OVER N CENTRAL CANADA FRIDAY NIGHT
LOOKS TO DIVE ACROSS S CENTRAL CANADA FOR THE LATTER HALF OF THE
WEEKEND. THE ONLY DAYS WHERE THE MERCURY MAY RISE AT OR ABOVE 20F
LOOKS TO BE SATURDAY...AND TO A LESSER EXTENT SUNDAY.
VERY COLD TUESDAY NIGHT...
GIVEN THE COLD AIR LOCKED IN PLACE...ANY MODERATE OR STRONG WINDS
WILL RESULT IN DANGEROUS WIND CHILLS. WIND CHILL VALUES WILL LIKELY
FALL TO THESE DANGEROUS VALUES TUESDAY NIGHT AS STRONG/COLD HIGH
PRESSURE SURGES IN AGAIN FROM THE NW. HOWEVER...WITH WINDS IN THE
COLDEST LOCATIONS LESS THAN OUR 10MPH WIND CHILL ADVISORY/WARNING
CRITERIA...HEADLINES MAY NOT BE POSTED /ALTHOUGH NAM GUIDANCE IS
NEAR/. WE WILL CONTINUE TO HIGHLIGHT THE DANGER HERE...IN THE
HWO...AND WITH SOCIAL MEDIA. THE GFS-MOS CAME IN WITH A FCST LOW OF
-22F AT CHAMPION/VAN RIPER...WITH -17F AT BOTH BERGLAND DAM AND IWD.
CONTINUED LAKE EFFECT SNOW SHOWERS THROUGH THURSDAY...MODERATE TO
HEAVY LES MAY BE ONGOING FOR MAINLY E ALGER/N SCHOOLCRAFT/N LUCE
COUNTIES TUESDAY MORNING. CONTINUED NW FLOW ON COLD AIR AVERAGING
-20 TO -23C AT 850MB WILL BE THE RULE UNTIL APPROX 6Z WEDNESDAY WHEN
THE WINDS BECOME DISRUPTED AS THE SFC TROUGH/LOW STUCK OVER SE LAKE
SUPERIOR WEAKENS AND BECOMES ABSORBED BY THE HIGH SET UP TO OUR NW.
WITH A MESO-LOW LIKELY DEVELOPING IT WILL BE DIFFICULT TO PIN POINT
WHERE AND FOR HOW LONG A DOMINANT BAND OF SNOW MAY
DEVELOP...ANYWHERE FROM NEAR MUNISING TO EAST OF GRAND MARAIS. WILL
WAIT FOR NEAR TERM MODELS TO COME INTO BETTER AGREEMENT BEFORE
REDUCING WATCH TO ADVISORIES...OR HOISTING LES WARNINGS FOR ALGER
AND LUCE COUNTIES.
LES WILL CONTINUE WEDNESDAY INTO THURSDAY...MAINLY ON THE N AND NE
SNOWBELTS. LATEST GUIDANCE INDICATES THE POTENTIAL FOR 3-8IN OF SNOW
ACROSS THE HURON MOUNTAINS FROM LATE WEDNESDAY MORNING THROUGH EARLY
THURSDAY MORNING. HEADLINES MAY BE NEEDED AS THE TIME NEARS.
WARMER AIR THIS WEEKEND...
AS NOTED PREVIOUSLY A SURGE OF RELATIVELY WARM AIR IS FIGURED FOR
THE UPCOMING WEEKEND. THE 30/00Z RUN OF THE GFS INCREASED THE 850MB
WINDS BY APPROX 5-10KTS...WITH THE ECMWF AND GFS SHOWING BETWEEN 40
AND 65KT SW TO W LLJ FROM ROUGHLY 00-18Z SATURDAY. THIS WILL ALLOW
850MB TEMPS TO RISE UP TO -4 TO -8C. AHEAD OF THE SFC LOW SET UP
FROM THE PLAINS STATES THROUGH W ONTARIO...RISING OVERNIGHT TEMPS
WILL BE LIKELY FRIDAY NIGHT INTO SATURDAY. THERE OF COURSE ARE SOME
TIMING DIFFERENCES...WITH THE LOW AND ITS ASSOCIATED COLD FRONT
BEING 6-12HRS QUICK OFF THE LATEST GFS. THE SLOWER ECMWF SOLUTION IS
BACKED UP AT LEAST EARLY SATURDAY BY THE CANADIAN AND DGEX.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 643 AM EST MON DEC 30 2013
IWD...ALTHOUGH SOME LIGHT SNOW IN ADVANCE OF ANOTHER DISTURBANCE MAY
ARRIVE LATE THIS AFTERNOON...CONDITIONS ARE LIKELY TO REMAIN VFR AS
THIS SYSTEM WILL BE MOISTURE DEPRIVED AND THE STRONGER DYNAMICS WILL
REMAIN TO THE SOUTH. A WIND SHIFT TO THE WNW IN ITS WAKE MAY
BRING A RETURN OF LK EFFECT -SHSN AND MVFR CONDITIONS DURING THE
EVNG.
CMX...WITH A SLOWLY BACKING NW TO W FLOW OF ARCTIC AIR...EXPECT LAKE
EFFECT -SHSN AND PREDOMINANT IFR VSBYS TO PERSIST THRU THE FCST
PERIOD. SHARPENING LOW LEVEL CONVERGENCE COINCIDENT WITH THE PASSAGE OF A
STRONGER DISTURBANCE/ACCOMPANYING LOW PRES TROF PASSAGE MAY BRING A
PERIOD OF HEAVIER SHSN/LIFR CONDITIONS LATE THIS AFTERNOON OR
EVENING.
SAW...WITH A DOWNSLOPE W WIND FLOW OF DRY ARCTIC AIR...EXPECT VFR
CONDITIONS TO DOMINATE THIS LOCATION THE ENTIRE FCST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 540 AM EST MON DEC 30 2013
WEST NORTHWEST WINDS TO 25 KNOTS ARE EXPECTED TO SLOWLY
DIMINISH...REDUCING THE POTENTIAL FOR FREEZING SPRAY OVER THE LAKE BY
THIS AFTERNOON. AS THE LINGERING SURFACE TROUGH OVER EASTERN LAKE
SUPERIOR STRENGTHENS TONIGHT AND SHIFTS EAST ON
TUESDAY...NORTHWESTERLY WINDS WILL INCREASE WITH SOME GUSTS TO 30KTS
OVER THE EASTERN LAKE TUESDAY AFTERNOON AND EVENING. THIS WILL ALSO
BRING AN INCREASED OPPORTUNITY FOR HEAVY FREEZING SPRAY THROUGH
TUESDAY NIGHT OVER THE EASTERN HALF OF LAKE SUPERIOR. ALTHOUGH THERE
STILL WILL BE A LINGERING TROUGH OVER EASTERN LAKE SUPERIOR INTO
WEDNESDAY...HIGH PRESSURE BUILDING OVER THE UPPER MISSISSIPPI VALLEY
WILL LEAD TO LIGHTER NORTHWESTERLY WINDS FOR WEDNESDAY AND
THURSDAY...BRINGING AN END TO THE POTENTIAL FOR HEAVY FREEZING SPRAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL ADVISORY UNTIL 10 AM EST /9 AM CST/ THIS MORNING FOR
MIZ002-004-005-009>011-084.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST THIS MORNING FOR MIZ085.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ006-007.
LAKE EFFECT SNOW WATCH FROM THIS EVENING THROUGH TUESDAY EVENING
FOR MIZ006-007.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST THIS MORNING FOR
LSZ248>251-264-267.
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST WEDNESDAY FOR LSZ266.
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
LSZ265.
HEAVY FREEZING SPRAY WARNING FROM 10 PM THIS EVENING TO 1 AM EST
WEDNESDAY FOR LSZ264.
HEAVY FREEZING SPRAY WARNING FROM 10 PM THIS EVENING TO 4 AM EST
WEDNESDAY FOR LSZ248>250.
HEAVY FREEZING SPRAY WARNING FROM 10 PM EST /9 PM CST/ THIS
EVENING TO 10 PM EST /9 PM CST/ TUESDAY FOR LSZ241>244.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
543 AM EST MON DEC 30 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 540 AM EST MON DEC 30 2013
WV IMAGERY AND RUC ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW FROM
CENTRAL CANADA INTO THE NRN GREAT LAKES AROUND THE POLAR VORTEX OVER
HUDSON BAY. ONE IN A SERIES OF CLIPPER SHORTWAVE TROUGHS OVER THE
NRN PLAINS SUPPORTED AN AREA OF LIGHT SNOW OVER THE DAKOTAS. AT THE
SFC...DIMINISHING WNW WINDS PREVAILED ACROSS THE REGION AHEAD
OF THE ARCTIC HIGH PRES RIDGE EXTENDING FROM NRN ALBERTA INTO THE
UPPER MS VALLEY. RADAR INDICATED WEAK MULTIPLE WIND PARALLEL LES
BANDS INTO UPPER MICHIGAN FROM MUNISING EASTWARD. ALTHOUGH 850 MB
TEMPS REMAINED AROUND -23C...INVERSION HEIGHTS AROUND 5K FT AND THE
VERY DRY UPSTREAM AIRMASS HAS LIMITED LES INTENSITY WITH LIGHT
SNOWFALL RATES OF SMALLER SNOWFLAKES. SATELLITE...SFC OBS AND WEB
CAMS ALSO INDICATED PERSIST LIGHT LES INTO THE WEST. IN AREAS WHERE
SKIES HAD CLEARED...INLAND TEMPS HAVE FALLEN OFF TO -10F TO -20F.
EVEN WITH RELATIVELY LIGHT WINDS OF 5 TO 10 MPH...WIND CHILL VALUES
HAD DROPPED INTO THE ADVISORY (-25 TO -30) RANGE.
TODAY...THE MODELS WERE CONSISTENT IN KEEPING THE LIGHT SNOW
ASSOCIATED WITH THE STRONGER FORCING AND ISENTROPIC LIFT ASSOCIATED
WITH THE SHRTWV SOUTH OF UPPER MI. HOWEVER...THE SHRTWV WILL BRING
BACKING WINDS TOWARD WRLY THAT WILL PUSH THE LES OVER THE EAST
OFFSHORE. THE BACKING TREND MAY ALSO RESULT IN ENHANCED LOW LEVEL
CONV IN THE KEWEENAW AND A PERIOD OF SLIGHTLY HEAVIER LES.
OTHERWISE...DIURNAL WARMING SHOULD BRING MODERATING WIND CHILL
VALUES BY MID MORNING. MAINLY JUST HIGH CLOUDS ARE EXPECTED OVER
MUCH OF THE CWA WITH TEMPS CLIMBING TO 0F TO 5F WEST AND CLOSER TO
10F ALONG LAKE SUPERIOR AND EAST.
TONIGHT...WITH A TROUGH ACROSS SRN LAKE SUPERIOR...THE HIGHER RES
MODELS SUGGEST A MESO-LOW MAY DEVELOP OVER THE SE PORTION OF THE LAKE
THAT MAY DROP INTO THE NE CWA EAST OF MUNISING OVERNIGHT AS WINDS
VEER AND INCREASE BEHIND THE SHRTWV. THIS COULD PRODUCE A PERIOD OF
HEAVY SNOW AS STRONGER MOISTURE/HEAT FLUX OFF THE LAKE IN THE CLOSED
CIRCULATION BRING THE DGZ INTO THE CONVECTIVE LAYER WITH POTENTIALLY
INTENSE LES BANDS. HOWEVER...AS EXPECTED WITH MESOSCALE
FEATURES...THERE IS STILL SIGNIFICANT UNCERTAINTY WITH THE
TIMING/LOCATION/DURATION OF ANY HEAVIER SNOW. SO...THE LES WATCH WAS
RETAINED. THE GREATEST ACCUMULATIONS ARE LIKELY FROM PICTURED ROCKS
AND GRAND MARAIS INTO NRN LUCE COUNTY. ALTHOUGH TEMPS ARE NOT
EXPECTED TO DROP AS MUCH TONIGHT WITH GREATER CLOUD COVER...SLIGHTLY
STRONGER WINDS MAY PUSH WIND CHILLS BACK INTO THE ADVISORY RANGE OVER
THE THE INTERIOR WEST HALF.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 506 AM EST MON DEC 30 2013
TAKING A LOOK AT THE LARGE SCALE PATTERN...THE UPPER GREAT LAKES
WILL REMAIN DOMINATED BY A TROUGH AT 500MB THROUGH THURSDAY. EVEN
WHEN THE MAIN 500MB LOW DOES EXIT OFF THE NE CANADIAN COAST ON
SATURDAY...ANOTHER LOW SITUATED OVER N CENTRAL CANADA FRIDAY NIGHT
LOOKS TO DIVE ACROSS S CENTRAL CANADA FOR THE LATTER HALF OF THE
WEEKEND. THE ONLY DAYS WHERE THE MERCURY MAY RISE AT OR ABOVE 20F
LOOKS TO BE SATURDAY...AND TO A LESSER EXTENT SUNDAY.
VERY COLD TUESDAY NIGHT...
GIVEN THE COLD AIR LOCKED IN PLACE...ANY MODERATE OR STRONG WINDS
WILL RESULT IN DANGEROUS WIND CHILLS. WIND CHILL VALUES WILL LIKELY
FALL TO THESE DANGEROUS VALUES TUESDAY NIGHT AS STRONG/COLD HIGH
PRESSURE SURGES IN AGAIN FROM THE NW. HOWEVER...WITH WINDS IN THE
COLDEST LOCATIONS LESS THAN OUR 10MPH WIND CHILL ADVISORY/WARNING
CRITERIA...HEADLINES MAY NOT BE POSTED /ALTHOUGH NAM GUIDANCE IS
NEAR/. WE WILL CONTINUE TO HIGHLIGHT THE DANGER HERE...IN THE
HWO...AND WITH SOCIAL MEDIA. THE GFS-MOS CAME IN WITH A FCST LOW OF
-22F AT CHAMPION/VAN RIPER...WITH -17F AT BOTH BERGLAND DAM AND IWD.
CONTINUED LAKE EFFECT SNOW SHOWERS THROUGH THURSDAY...MODERATE TO
HEAVY LES MAY BE ONGOING FOR MAINLY E ALGER/N SCHOOLCRAFT/N LUCE
COUNTIES TUESDAY MORNING. CONTINUED NW FLOW ON COLD AIR AVERAGING
-20 TO -23C AT 850MB WILL BE THE RULE UNTIL APPROX 6Z WEDNESDAY WHEN
THE WINDS BECOME DISRUPTED AS THE SFC TROUGH/LOW STUCK OVER SE LAKE
SUPERIOR WEAKENS AND BECOMES ABSORBED BY THE HIGH SET UP TO OUR NW.
WITH A MESO-LOW LIKELY DEVELOPING IT WILL BE DIFFICULT TO PIN POINT
WHERE AND FOR HOW LONG A DOMINANT BAND OF SNOW MAY
DEVELOP...ANYWHERE FROM NEAR MUNISING TO EAST OF GRAND MARAIS. WILL
WAIT FOR NEAR TERM MODELS TO COME INTO BETTER AGREEMENT BEFORE
REDUCING WATCH TO ADVISORIES...OR HOISTING LES WARNINGS FOR ALGER
AND LUCE COUNTIES.
LES WILL CONTINUE WEDNESDAY INTO THURSDAY...MAINLY ON THE N AND NE
SNOWBELTS. LATEST GUIDANCE INDICATES THE POTENTIAL FOR 3-8IN OF SNOW
ACROSS THE HURON MOUNTAINS FROM LATE WEDNESDAY MORNING THROUGH EARLY
THURSDAY MORNING. HEADLINES MAY BE NEEDED AS THE TIME NEARS.
WARMER AIR THIS WEEKEND...
AS NOTED PREVIOUSLY A SURGE OF RELATIVELY WARM AIR IS FIGURED FOR
THE UPCOMING WEEKEND. THE 30/00Z RUN OF THE GFS INCREASED THE 850MB
WINDS BY APPROX 5-10KTS...WITH THE ECMWF AND GFS SHOWING BETWEEN 40
AND 65KT SW TO W LLJ FROM ROUGHLY 00-18Z SATURDAY. THIS WILL ALLOW
850MB TEMPS TO RISE UP TO -4 TO -8C. AHEAD OF THE SFC LOW SET UP
FROM THE PLAINS STATES THROUGH W ONTARIO...RISING OVERNIGHT TEMPS
WILL BE LIKELY FRIDAY NIGHT INTO SATURDAY. THERE OF COURSE ARE SOME
TIMING DIFFERENCES...WITH THE LOW AND ITS ASSOCIATED COLD FRONT
BEING 6-12HRS QUICK OFF THE LATEST GFS. THE SLOWER ECMWF SOLUTION IS
BACKED UP AT LEAST EARLY SATURDAY BY THE CANADIAN AND DGEX.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1247 AM EST MON DEC 30 2013
IWD...AS THE LLVL FLOW BACKS SLOWLY TOWARD THE WSW THRU THE NGT...
EXPECT LINGERING -SHSN/CLDS TO SHIFT TO THE N...WITH A TREND TOWARD
PREDOMINANT VFR WX. ALTHOUGH SOME LGT SN IN ADVANCE OF ANOTHER
DISTURBANCE MAY ARRIVE LATE MON AFTN...CONDITIONS ARE LIKELY TO
REMAIN VFR AS THIS SYS WL BE MSTR DEPRIVED AND THE SHARPER DYNAMICS
WL REMAIN TO THE S. A WSHFT TOWARD THE WNW IN ITS WAKE MAY BRING A
RETURN OF LK EFFECT -SHSN AND MVFR CONDITIONS DURING THE EVNG.
CMX...WITH A SLOWLY BACKING NW TO W FLOW OF ARCTIC AIR...EXPECT LK
EFFECT -SHSN AND PREDOMINANT IFR VSBYS TO PERSIST THRU THE FCST
PERIOD. SHARPENING LLVL CNVGC COINCIDENT WITH THE PASSAGE OF A
STRONGER DISTURBANCE/ACCOMPANYING LO PRES TROF PASSAGE MAY BRING A
PERIOD OF HEAVIER SHSN/LIFR CONDITIONS THIS EVNG.
SAW...WITH A DOWNSLOPE W WIND FLOW OF DRY ARCTIC AIR...EXPECT VFR
CONDITIONS TO DOMINATE THIS LOCATION THE ENTIRE FCST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 540 AM EST MON DEC 30 2013
WEST NORTHWEST WINDS TO 25 KNOTS ARE EXPECTED TO SLOWLY
DIMINISH...REDUCING THE POTENTIAL FOR FREEZING SPRAY OVER THE LAKE BY
THIS AFTERNOON. AS THE LINGERING SURFACE TROUGH OVER EASTERN LAKE
SUPERIOR STRENGTHENS TONIGHT AND SHIFTS EAST ON
TUESDAY...NORTHWESTERLY WINDS WILL INCREASE WITH SOME GUSTS TO 30KTS
OVER THE EASTERN LAKE TUESDAY AFTERNOON AND EVENING. THIS WILL ALSO
BRING AN INCREASED OPPORTUNITY FOR HEAVY FREEZING SPRAY THROUGH
TUESDAY NIGHT OVER THE EASTERN HALF OF LAKE SUPERIOR. ALTHOUGH THERE
STILL WILL BE A LINGERING TROUGH OVER EASTERN LAKE SUPERIOR INTO
WEDNESDAY...HIGH PRESSURE BUILDING OVER THE UPPER MISSISSIPPI VALLEY
WILL LEAD TO LIGHTER NORTHWESTERLY WINDS FOR WEDNESDAY AND
THURSDAY...BRINGING AN END TO THE POTENTIAL FOR HEAVY FREEZING SPRAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL ADVISORY UNTIL 10 AM EST /9 AM CST/ THIS MORNING FOR
MIZ002-004-005-009>011-084.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST THIS MORNING FOR MIZ085.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ006-007.
LAKE EFFECT SNOW WATCH FROM THIS EVENING THROUGH TUESDAY EVENING
FOR MIZ006-007.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST THIS MORNING FOR
LSZ248>251-264-267.
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST WEDNESDAY FOR LSZ266.
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
LSZ265.
HEAVY FREEZING SPRAY WARNING FROM 10 PM THIS EVENING TO 1 AM EST
WEDNESDAY FOR LSZ264.
HEAVY FREEZING SPRAY WARNING FROM 10 PM THIS EVENING TO 4 AM EST
WEDNESDAY FOR LSZ248>250.
HEAVY FREEZING SPRAY WARNING FROM 10 PM EST /9 PM CST/ THIS
EVENING TO 10 PM EST /9 PM CST/ TUESDAY FOR LSZ241>244.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
507 AM EST MON DEC 30 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 424 PM EST SUN DEC 29 2013
ARCTIC AIR AND CONTINUED LAKE EFFECT OFF LAKE SUPERIOR WILL BE THE
MAIN CONCERNS FOR THE SHORT TERM PERIOD.
THE SURFACE LOW THAT BROUGHT THE SURGE OF COLD AIR CONTINUES TO
SLIDE EAST OF THE AREA...WHILE HIGH PRESSURE HAS BUILT INTO THE
NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY. THE EXITING LOW HAS
LEFT A SURFACE TROUGH OVER EASTERN LAKE SUPERIOR. ALOFT...AREA IS
UNDER AN UPPER TROUGH THAT COVERS MUCH OF THE EASTERN CONUS AND HAS
LED TO ARCTIC AIR SPILLING SOUTHEAST OVER THE UPPER GREAT LAKES LAST
NIGHT. THIS COLD AIR HAS BEEN PRODUCING LAKE EFFECT SNOW SHOWERS IN
THE NORTH-NORTHWEST WIND LOCATIONS TODAY. LATEST RADAR/SATELLITE
DATA INDICATES THE BEST BANDS OVER FAR EASTERN MARQUETTE COUNTY
AND ALGER COUNTIES...WHERE RADAR RETURNS HAVE BEEN REACHING
7KFT. HAVE STARTED SEEING THE LOW LEVEL WINDS BACKING ASSOCIATED
WITH THE HIGH PRESSURE RIDGE OVER THE LAST FEW HOURS...ESPECIALLY
OVER THE WESTERN LAKE...AND THAT HAS STARTED TO PUSH THE BANDS OVER
MARQUETTE COUNTY EASTWARD. WITH AT LEAST HALF OF THE CLOUD BEING
ABOVE THE DGZ BASED ON RAP INITIAL SOUNDINGS...CALLS TO SPOTTERS
HAS INDICATED JUST A COUPLE INCHES OF ADDITIONAL SNOW
ACCUMULATION TODAY. THE BIGGEST ISSUE HAS BEEN THE SMALL FLAKES
REDUCING VISIBILITIES...ALONG WITH GUSTY WINDS TO 30-35MPH EAST
OF MARQUETTE...AND CAUSING BRIEF WHITEOUTS ALONG M-28 IN ALGER
COUNTY. A CALL TO THE ALGER COUNTY SHERIFF INDICATED SEVERAL
ACCIDENTS ON THAT STRETCH...WITH THEM ENCOURAGING TRAVEL ALONG
M-94 INSTEAD.
WITH THE COLD AIR IN PLACE AND SOME LOW LEVEL MOISTURE...EXPECT THE
LAKE EFFECT TO CONTINUE THROUGH THE SHORT TERM PERIOD. THE
LOCATION OF THE SNOW WILL BE DETERMINED BY BOUNDARY LAYER WINDS.
SINCE THE HIGH OVER SOUTHEAST SOUTH DAKOTA WILL DRIFT TO THE
SOUTHEAST THROUGH THE NIGHT...IT WILL PUSH A RIDGE INTO THE
SOUTHWEST HALF OF UPPER MICHIGAN. THIS RIDGE WILL DO TWO
THINGS...BACK THE WINDS TO MORE OF A WEST-NORTHWEST DIRECTION AND
CONTINUE TO PROVIDE DRY AIR AND SUBSIDENCE ABOVE 850MB. THOSE
BACKING WINDS WILL ALSO BE AIDED BY A SHORTWAVE DEPARTING THE
CANADIAN ROCKIES AND MOVING INTO THE NORTHERN PLAINS ON
MONDAY. THIS WILL LEAD TO WINDS TRANSITIONING FROM THE
NORTH-NORTHWEST LATE THIS AFTERNOON TO THE NORTHWEST THIS EVENING
AND EVENTUALLY NEARLY WESTERLY BY 18Z MONDAY. THEREFORE...WOULD
EXPECT THE PURE LAKE EFFECT BANDS (NO SHORTWAVE HELP) TO FOLLOW
SUIT. 850MB TEMPS WILL REMAIN FAIRLY STEADY THROUGH MONDAY AND
AROUND -23C...LEADING TO DELTA-T VALUES AROUND THE MID 20S. BUT
THIS COLD AIR WILL LEAD TO MUCH OF THE CLOUD BEING AT THE HIGH END
OF THE DGZ OR ABOVE IT...SO WOULD EXPECT SNOW RATIOS TO BE ON THE
LOWER END FOR LAKE EFFECT AND IN MOST SITUATIONS BELOW 20 TO 1. IN
THE STRONGEST BANDS OVER THE EAST AND THE BETTER LAKE
MODIFICATION...DID KEEP SOME LOW 20S IN THE FORECAST. AS SEEN ON
SATELLITE NEAR IRONWOOD THIS AFTERNOON...THE STRONGEST BANDS
WILL BE ON THE SOUTHWEST EDGE OF THE LES DUE TO THE ENHANCED
CONVERGENCE FROM THE BACKING WINDS. ALTHOUGH THIS WILL STRENGTHEN
THE BANDS...THINK THE CONSISTENT BACKING FLOW (ALONG WITH THE LOWER
RATIOS) WILL BE ENOUGH TO KEEP AMOUNTS GENERALLY LIGHT. HAVE KEPT
AMOUNTS FAIRLY SIMILAR TO WHAT WAS SEEN DURING THE DAY TODAY IN THE
LES LOCATIONS (1-2.5IN)...BUT DO HAVE SLIGHTLY HIGHER AMOUNTS
(APPROACHING 4) OVER THE EAST WITH THE SLOWER BACKING TREND. THE
LONGER FETCH WITH THE WEST TO WEST-SOUTHWEST WINDS OVER WESTERN
LAKE SUPERIOR COULD LEAD TO AN INCREASE IN INTENSITY OF THE MAIN
LAKE EFFECT BAND OVER THE KEWEENAW PENINSULA (NORTH OF HOUGHTON).
LAKE INDUCED EQUILIBRIUM LEVELS STILL AROUND 7KFT AND MUCH OF THE
CLOUDS IS AT HIGH END OF DGZ OR ABOVE SO WON/T GO TOO HIGH ON
AMOUNTS IN THE LATE MORNING AND INTO THE AFTERNOON...BUT COULD NEAR
LOW END ADVISORY AMOUNTS.
AS FOR SNOW HEADLINES...CANCELLED BARAGA AND SOUTHERN HOUGHTON
EARLY AND WILL ALLOW THE REST OF THE WESTERN AREAS EXPIRE AT 00Z AS
WINDS WILL DIMINISH AND JUST LIGHT SNOW WILL REMAIN. OVER THE
EAST...HAVE KEPT THEM AS IS WITH THE BAD CONDITIONS REPORTED ALONG
M-28 IN ALGER COUNTY...ALTHOUGH MOST LOCATIONS TONIGHT WILL
STRUGGLE TO REACH THE 4 INCH IN 12HR AMOUNTS DUE TO THE SMALLER
FLAKES.
AS FOR THE WIND CHILL HEADLINES...CLOUDS WILL DETERMINE THE LOWS
TONIGHT. UNFORTUNATELY IT COMES DOWN TO THE DIMINISHING LAKE
EFFECT CLOUDS OVER THE WEST AND THEN HIGH CLOUDS STREAMING IN LATE
TONIGHT AHEAD OF THE NEXT WAVE IN THE UPPER TROUGH SLIDING SOUTHEAST
THROUGH THE NORTHERN PLAINS. 12Z GFS/ECMWF ARE THE MOST AGGRESSIVE
WITH THESE HIGH CLOUD...COVERING THE WESTERN HALF OF THE CWA BY
12Z. WITH THE COLD AIR IN PLACE...THINK THAT TEMPS WILL COOL
FAIRLY QUICKLY IN AREAS THAT SKIES CLEAR. THE REGIONAL
GEM...WHICH TRADITIONALLY DOES WELL IN THESE CASES ONLY HAS LOWS
IN THE LOW TEENS BELOW ZERO ALONG THE WISCONSIN BORDER AND SINGLE
DIGITS ELSEWHERE. THIS PROVIDES SOME CONCERN TO THE GOING FORECAST
AND TWEAKED VALUES SLIGHTLY HIGHER. ON THE OTHER SIDE...18Z HRRR/RAP
FORECASTS HAVE LOWS AROUND -20 TO -23 TONIGHT...BUT IN MOST
SITUATIONS THEY ARE TOO LOW. EVEN WITH THE SLIGHT TWEAKS...WIND
CHILL ADVISORY LOOKS GOOD FOR AREAS NEAR THE WISCONSIN BORDER AND
HAVE LEFT IT AS IS. A LITTLE CONCERNED ON LAKE CLOUDS LINGERING
OVER MARQUETTE/BARAGA...BUT LOCATIONS WELL INLAND SHOULD CLEAR OUT
LATE AND ALLOW FOR TEMPS TO FALL. FINALLY...MAY NEED TO MONITOR
MENOMINEE COUNTY...AS GOING FORECAST HAS WIND CHILLS NEARING -25
OVER THE WESTERN REACHES OF THE COUNTY.
THE PREVIOUSLY MENTIONED MID/HIGH CLOUDS WILL MOVE ACROSS THE REST
OF THE CWA DURING THE DAY ON MONDAY AND LEAD TO A FILTERED SUNSHINE
AWAY FROM THE LAKE EFFECT. THERE COULD EVEN BE A FEW SNOW SHOWERS
NEAR IRONWOOD LATE MONDAY AFTERNOON ON THE NORTH EDGE OF THE WAVE
MOVING INTO WISCONSIN ON MONDAY EVENING. HIGHS ON MONDAY WILL BE
15-20 DEGREES BELOW NORMAL AND IN THE SINGLE DIGITS ABOVE ZERO FOR
MOST LOCATIONS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 506 AM EST MON DEC 30 2013
TAKING A LOOK AT THE LARGE SCALE PATTERN...THE UPPER GREAT LAKES
WILL REMAIN DOMINATED BY A TROUGH AT 500MB THROUGH THURSDAY. EVEN
WHEN THE MAIN 500MB LOW DOES EXIT OFF THE NE CANADIAN COAST ON
SATURDAY...ANOTHER LOW SITUATED OVER N CENTRAL CANADA FRIDAY NIGHT
LOOKS TO DIVE ACROSS S CENTRAL CANADA FOR THE LATTER HALF OF THE
WEEKEND. THE ONLY DAYS WHERE THE MERCURY MAY RISE AT OR ABOVE 20F
LOOKS TO BE SATURDAY...AND TO A LESSER EXTENT SUNDAY.
VERY COLD TUESDAY NIGHT...
GIVEN THE COLD AIR LOCKED IN PLACE...ANY MODERATE OR STRONG WINDS
WILL RESULT IN DANGEROUS WIND CHILLS. WIND CHILL VALUES WILL LIKELY
FALL TO THESE DANGEROUS VALUES TUESDAY NIGHT AS STRONG/COLD HIGH
PRESSURE SURGES IN AGAIN FROM THE NW. HOWEVER...WITH WINDS IN THE
COLDEST LOCATIONS LESS THAN OUR 10MPH WIND CHILL ADVISORY/WARNING
CRITERIA...HEADLINES MAY NOT BE POSTED /ALTHOUGH NAM GUIDANCE IS
NEAR/. WE WILL CONTINUE TO HIGHLIGHT THE DANGER HERE...IN THE
HWO...AND WITH SOCIAL MEDIA. THE GFS-MOS CAME IN WITH A FCST LOW OF
-22F AT CHAMPION/VAN RIPER...WITH -17F AT BOTH BERGLAND DAM AND IWD.
CONTINUED LAKE EFFECT SNOW SHOWERS THROUGH THURSDAY...MODERATE TO
HEAVY LES MAY BE ONGOING FOR MAINLY E ALGER/N SCHOOLCRAFT/N LUCE
COUNTIES TUESDAY MORNING. CONTINUED NW FLOW ON COLD AIR AVERAGING
-20 TO -23C AT 850MB WILL BE THE RULE UNTIL APPROX 6Z WEDNESDAY WHEN
THE WINDS BECOME DISRUPTED AS THE SFC TROUGH/LOW STUCK OVER SE LAKE
SUPERIOR WEAKENS AND BECOMES ABSORBED BY THE HIGH SET UP TO OUR NW.
WITH A MESO-LOW LIKELY DEVELOPING IT WILL BE DIFFICULT TO PIN POINT
WHERE AND FOR HOW LONG A DOMINANT BAND OF SNOW MAY
DEVELOP...ANYWHERE FROM NEAR MUNISING TO EAST OF GRAND MARAIS. WILL
WAIT FOR NEAR TERM MODELS TO COME INTO BETTER AGREEMENT BEFORE
REDUCING WATCH TO ADVISORIES...OR HOISTING LES WARNINGS FOR ALGER
AND LUCE COUNTIES.
LES WILL CONTINUE WEDNESDAY INTO THURSDAY...MAINLY ON THE N AND NE
SNOWBELTS. LATEST GUIDANCE INDICATES THE POTENTIAL FOR 3-8IN OF SNOW
ACROSS THE HURON MOUNTAINS FROM LATE WEDNESDAY MORNING THROUGH EARLY
THURSDAY MORNING. HEADLINES MAY BE NEEDED AS THE TIME NEARS.
WARMER AIR THIS WEEKEND...
AS NOTED PREVIOUSLY A SURGE OF RELATIVELY WARM AIR IS FIGURED FOR
THE UPCOMING WEEKEND. THE 30/00Z RUN OF THE GFS INCREASED THE 850MB
WINDS BY APPROX 5-10KTS...WITH THE ECMWF AND GFS SHOWING BETWEEN 40
AND 65KT SW TO W LLJ FROM ROUGHLY 00-18Z SATURDAY. THIS WILL ALLOW
850MB TEMPS TO RISE UP TO -4 TO -8C. AHEAD OF THE SFC LOW SET UP
FROM THE PLAINS STATES THROUGH W ONTARIO...RISING OVERNIGHT TEMPS
WILL BE LIKELY FRIDAY NIGHT INTO SATURDAY. THERE OF COURSE ARE SOME
TIMING DIFFERENCES...WITH THE LOW AND ITS ASSOCIATED COLD FRONT
BEING 6-12HRS QUICK OFF THE LATEST GFS. THE SLOWER ECMWF SOLUTION IS
BACKED UP AT LEAST EARLY SATURDAY BY THE CANADIAN AND DGEX.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1247 AM EST MON DEC 30 2013
IWD...AS THE LLVL FLOW BACKS SLOWLY TOWARD THE WSW THRU THE NGT...
EXPECT LINGERING -SHSN/CLDS TO SHIFT TO THE N...WITH A TREND TOWARD
PREDOMINANT VFR WX. ALTHOUGH SOME LGT SN IN ADVANCE OF ANOTHER
DISTURBANCE MAY ARRIVE LATE MON AFTN...CONDITIONS ARE LIKELY TO
REMAIN VFR AS THIS SYS WL BE MSTR DEPRIVED AND THE SHARPER DYNAMICS
WL REMAIN TO THE S. A WSHFT TOWARD THE WNW IN ITS WAKE MAY BRING A
RETURN OF LK EFFECT -SHSN AND MVFR CONDITIONS DURING THE EVNG.
CMX...WITH A SLOWLY BACKING NW TO W FLOW OF ARCTIC AIR...EXPECT LK
EFFECT -SHSN AND PREDOMINANT IFR VSBYS TO PERSIST THRU THE FCST
PERIOD. SHARPENING LLVL CNVGC COINCIDENT WITH THE PASSAGE OF A
STRONGER DISTURBANCE/ACCOMPANYING LO PRES TROF PASSAGE MAY BRING A
PERIOD OF HEAVIER SHSN/LIFR CONDITIONS THIS EVNG.
SAW...WITH A DOWNSLOPE W WIND FLOW OF DRY ARCTIC AIR...EXPECT VFR
CONDITIONS TO DOMINATE THIS LOCATION THE ENTIRE FCST PERIOD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 PM EST SUN DEC 29 2013
NORTHWESTERLY WINDS OF 15 TO 25 KNOTS WILL CONTINUE INTO THIS
EVENING BEFORE BACKING TO THE WEST-NORTHWEST LATE TONIGHT INTO
MONDAY. WINDS WILL WEAKEN SLIGHTLY AS THIS OCCURS AND SLOWLY
DIMINISH THE POTENTIAL FOR FREEZING SPRAY OVER THE LAKE BY MONDAY
AFTERNOON. AS THE LINGERING SURFACE TROUGH OVER EASTERN LAKE
SUPERIOR STRENGTHENS ON MONDAY NIGHT AND SHIFTS EAST ON
TUESDAY...NORTHWESTERLY WINDS WILL INCREASE WITH SOME GUSTS TO 30KTS
OVER THE EASTERN LAKE TUESDAY AFTERNOON AND EVENING. THIS WILL ALSO
BRING AN INCREASED OPPORTUNITY FOR HEAVY FREEZING SPRAY THROUGH
TUESDAY NIGHT OVER THE EASTERN HALF OF LAKE SUPERIOR. ALTHOUGH
THERE STILL WILL BE A LINGERING TROUGH OVER EASTERN LAKE SUPERIOR
INTO WEDNESDAY...HIGH PRESSURE BUILDING OVER THE UPPER MISSISSIPPI
VALLEY WILL LEAD TO LIGHTER NORTHWESTERLY WINDS FOR WEDNESDAY AND
THURSDAY...BRINGING AN END TO THE POTENTIAL FOR HEAVY FREEZING
SPRAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL ADVISORY UNTIL 10 AM EST /9 AM CST/ THIS MORNING FOR
MIZ002-004-005-009>011-084.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST THIS MORNING FOR MIZ085.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ006-007.
LAKE EFFECT SNOW WATCH FROM THIS EVENING THROUGH TUESDAY EVENING
FOR MIZ006-007.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST THIS MORNING FOR
LSZ248>251-264-267.
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST WEDNESDAY FOR LSZ266.
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
LSZ265.
HEAVY FREEZING SPRAY WARNING FROM 10 PM THIS EVENING TO 1 AM EST
WEDNESDAY FOR LSZ264.
HEAVY FREEZING SPRAY WARNING FROM 10 PM THIS EVENING TO 4 AM EST
WEDNESDAY FOR LSZ248>250.
HEAVY FREEZING SPRAY WARNING FROM 10 PM EST /9 PM CST/ THIS
EVENING TO 10 PM EST /9 PM CST/ TUESDAY FOR LSZ241>244.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...KF
AVIATION...KC
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1252 AM EST MON DEC 30 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 424 PM EST SUN DEC 29 2013
ARCTIC AIR AND CONTINUED LAKE EFFECT OFF LAKE SUPERIOR WILL BE THE
MAIN CONCERNS FOR THE SHORT TERM PERIOD.
THE SURFACE LOW THAT BROUGHT THE SURGE OF COLD AIR CONTINUES TO
SLIDE EAST OF THE AREA...WHILE HIGH PRESSURE HAS BUILT INTO THE
NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY. THE EXITING LOW HAS
LEFT A SURFACE TROUGH OVER EASTERN LAKE SUPERIOR. ALOFT...AREA IS
UNDER AN UPPER TROUGH THAT COVERS MUCH OF THE EASTERN CONUS AND HAS
LED TO ARCTIC AIR SPILLING SOUTHEAST OVER THE UPPER GREAT LAKES LAST
NIGHT. THIS COLD AIR HAS BEEN PRODUCING LAKE EFFECT SNOW SHOWERS IN
THE NORTH-NORTHWEST WIND LOCATIONS TODAY. LATEST RADAR/SATELLITE
DATA INDICATES THE BEST BANDS OVER FAR EASTERN MARQUETTE COUNTY
AND ALGER COUNTIES...WHERE RADAR RETURNS HAVE BEEN REACHING
7KFT. HAVE STARTED SEEING THE LOW LEVEL WINDS BACKING ASSOCIATED
WITH THE HIGH PRESSURE RIDGE OVER THE LAST FEW HOURS...ESPECIALLY
OVER THE WESTERN LAKE...AND THAT HAS STARTED TO PUSH THE BANDS OVER
MARQUETTE COUNTY EASTWARD. WITH AT LEAST HALF OF THE CLOUD BEING
ABOVE THE DGZ BASED ON RAP INITIAL SOUNDINGS...CALLS TO SPOTTERS
HAS INDICATED JUST A COUPLE INCHES OF ADDITIONAL SNOW
ACCUMULATION TODAY. THE BIGGEST ISSUE HAS BEEN THE SMALL FLAKES
REDUCING VISIBILITIES...ALONG WITH GUSTY WINDS TO 30-35MPH EAST
OF MARQUETTE...AND CAUSING BRIEF WHITEOUTS ALONG M-28 IN ALGER
COUNTY. A CALL TO THE ALGER COUNTY SHERIFF INDICATED SEVERAL
ACCIDENTS ON THAT STRETCH...WITH THEM ENCOURAGING TRAVEL ALONG
M-94 INSTEAD.
WITH THE COLD AIR IN PLACE AND SOME LOW LEVEL MOISTURE...EXPECT THE
LAKE EFFECT TO CONTINUE THROUGH THE SHORT TERM PERIOD. THE
LOCATION OF THE SNOW WILL BE DETERMINED BY BOUNDARY LAYER WINDS.
SINCE THE HIGH OVER SOUTHEAST SOUTH DAKOTA WILL DRIFT TO THE
SOUTHEAST THROUGH THE NIGHT...IT WILL PUSH A RIDGE INTO THE
SOUTHWEST HALF OF UPPER MICHIGAN. THIS RIDGE WILL DO TWO
THINGS...BACK THE WINDS TO MORE OF A WEST-NORTHWEST DIRECTION AND
CONTINUE TO PROVIDE DRY AIR AND SUBSIDENCE ABOVE 850MB. THOSE
BACKING WINDS WILL ALSO BE AIDED BY A SHORTWAVE DEPARTING THE
CANADIAN ROCKIES AND MOVING INTO THE NORTHERN PLAINS ON
MONDAY. THIS WILL LEAD TO WINDS TRANSITIONING FROM THE
NORTH-NORTHWEST LATE THIS AFTERNOON TO THE NORTHWEST THIS EVENING
AND EVENTUALLY NEARLY WESTERLY BY 18Z MONDAY. THEREFORE...WOULD
EXPECT THE PURE LAKE EFFECT BANDS (NO SHORTWAVE HELP) TO FOLLOW
SUIT. 850MB TEMPS WILL REMAIN FAIRLY STEADY THROUGH MONDAY AND
AROUND -23C...LEADING TO DELTA-T VALUES AROUND THE MID 20S. BUT
THIS COLD AIR WILL LEAD TO MUCH OF THE CLOUD BEING AT THE HIGH END
OF THE DGZ OR ABOVE IT...SO WOULD EXPECT SNOW RATIOS TO BE ON THE
LOWER END FOR LAKE EFFECT AND IN MOST SITUATIONS BELOW 20 TO 1. IN
THE STRONGEST BANDS OVER THE EAST AND THE BETTER LAKE
MODIFICATION...DID KEEP SOME LOW 20S IN THE FORECAST. AS SEEN ON
SATELLITE NEAR IRONWOOD THIS AFTERNOON...THE STRONGEST BANDS
WILL BE ON THE SOUTHWEST EDGE OF THE LES DUE TO THE ENHANCED
CONVERGENCE FROM THE BACKING WINDS. ALTHOUGH THIS WILL STRENGTHEN
THE BANDS...THINK THE CONSISTENT BACKING FLOW (ALONG WITH THE LOWER
RATIOS) WILL BE ENOUGH TO KEEP AMOUNTS GENERALLY LIGHT. HAVE KEPT
AMOUNTS FAIRLY SIMILAR TO WHAT WAS SEEN DURING THE DAY TODAY IN THE
LES LOCATIONS (1-2.5IN)...BUT DO HAVE SLIGHTLY HIGHER AMOUNTS
(APPROACHING 4) OVER THE EAST WITH THE SLOWER BACKING TREND. THE
LONGER FETCH WITH THE WEST TO WEST-SOUTHWEST WINDS OVER WESTERN
LAKE SUPERIOR COULD LEAD TO AN INCREASE IN INTENSITY OF THE MAIN
LAKE EFFECT BAND OVER THE KEWEENAW PENINSULA (NORTH OF HOUGHTON).
LAKE INDUCED EQUILIBRIUM LEVELS STILL AROUND 7KFT AND MUCH OF THE
CLOUDS IS AT HIGH END OF DGZ OR ABOVE SO WON/T GO TOO HIGH ON
AMOUNTS IN THE LATE MORNING AND INTO THE AFTERNOON...BUT COULD NEAR
LOW END ADVISORY AMOUNTS.
AS FOR SNOW HEADLINES...CANCELLED BARAGA AND SOUTHERN HOUGHTON
EARLY AND WILL ALLOW THE REST OF THE WESTERN AREAS EXPIRE AT 00Z AS
WINDS WILL DIMINISH AND JUST LIGHT SNOW WILL REMAIN. OVER THE
EAST...HAVE KEPT THEM AS IS WITH THE BAD CONDITIONS REPORTED ALONG
M-28 IN ALGER COUNTY...ALTHOUGH MOST LOCATIONS TONIGHT WILL
STRUGGLE TO REACH THE 4 INCH IN 12HR AMOUNTS DUE TO THE SMALLER
FLAKES.
AS FOR THE WIND CHILL HEADLINES...CLOUDS WILL DETERMINE THE LOWS
TONIGHT. UNFORTUNATELY IT COMES DOWN TO THE DIMINISHING LAKE
EFFECT CLOUDS OVER THE WEST AND THEN HIGH CLOUDS STREAMING IN LATE
TONIGHT AHEAD OF THE NEXT WAVE IN THE UPPER TROUGH SLIDING SOUTHEAST
THROUGH THE NORTHERN PLAINS. 12Z GFS/ECMWF ARE THE MOST AGGRESSIVE
WITH THESE HIGH CLOUD...COVERING THE WESTERN HALF OF THE CWA BY
12Z. WITH THE COLD AIR IN PLACE...THINK THAT TEMPS WILL COOL
FAIRLY QUICKLY IN AREAS THAT SKIES CLEAR. THE REGIONAL
GEM...WHICH TRADITIONALLY DOES WELL IN THESE CASES ONLY HAS LOWS
IN THE LOW TEENS BELOW ZERO ALONG THE WISCONSIN BORDER AND SINGLE
DIGITS ELSEWHERE. THIS PROVIDES SOME CONCERN TO THE GOING FORECAST
AND TWEAKED VALUES SLIGHTLY HIGHER. ON THE OTHER SIDE...18Z HRRR/RAP
FORECASTS HAVE LOWS AROUND -20 TO -23 TONIGHT...BUT IN MOST
SITUATIONS THEY ARE TOO LOW. EVEN WITH THE SLIGHT TWEAKS...WIND
CHILL ADVISORY LOOKS GOOD FOR AREAS NEAR THE WISCONSIN BORDER AND
HAVE LEFT IT AS IS. A LITTLE CONCERNED ON LAKE CLOUDS LINGERING
OVER MARQUETTE/BARAGA...BUT LOCATIONS WELL INLAND SHOULD CLEAR OUT
LATE AND ALLOW FOR TEMPS TO FALL. FINALLY...MAY NEED TO MONITOR
MENOMINEE COUNTY...AS GOING FORECAST HAS WIND CHILLS NEARING -25
OVER THE WESTERN REACHES OF THE COUNTY.
THE PREVIOUSLY MENTIONED MID/HIGH CLOUDS WILL MOVE ACROSS THE REST
OF THE CWA DURING THE DAY ON MONDAY AND LEAD TO A FILTERED SUNSHINE
AWAY FROM THE LAKE EFFECT. THERE COULD EVEN BE A FEW SNOW SHOWERS
NEAR IRONWOOD LATE MONDAY AFTERNOON ON THE NORTH EDGE OF THE WAVE
MOVING INTO WISCONSIN ON MONDAY EVENING. HIGHS ON MONDAY WILL BE
15-20 DEGREES BELOW NORMAL AND IN THE SINGLE DIGITS ABOVE ZERO FOR
MOST LOCATIONS.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 425 PM EST SUN DEC 29 2013
BIGGEST CONCERNS IN THE EXTENDED FOCUS ON THE POTENTIAL FOR HEAVY
LAKE EFFECT SNOW OVER THE NE CWA MON NIGHT INTO TUESDAY AND ALSO
ADVISORY LEVEL WIND CHILLS FOR SOME AREAS INTO MIDWEEK.
MON NIGHT INTO TUE...AS THE POLAR VORTEX SLOWLY SHIFTS SE FROM
HUDSON BAY...THE MODELS SUGGEST A SHORTWAVE TROUGH WILL MOVE THROUGH
THE UPPER MS VALLEY TOWARD THE UPPER GREAT LAKES. THE BEST ISENTROPIC
LIFT NEAR THE 850 MB FRONT AND POTENTIAL FOR WIDESPREAD LIGHT SNOW
IS EXPECTED TO REMAIN TO THE SOUTH OF UPPER MI. AS THE LOW LEVEL
WINDS BACK W OR WSW AHEAD OF THE SHRTWV ON MONDAY...THE LES OVER THE
NE CWA WILL GRADUALLY LIFT TO THE NORTH AND POSSIBLY MOVE OFFSHORE
BY LATE IN THE DAY. VEERING WINDS IN THE WAKE OF THE SHRTWV WILL
PUSH THE LES BACK INTO AREAS FAVORED BY NW FLOW BY LATE EVENING.
LAKE INDUCED TROUGHING IS EXPECTED TO FOCUS THE STRONGEST LOW LEVEL
CONV BACK INTO THE NE PORTION OF THE CWA FROM P53 EASTWARD. NAM FCST
SOUNDINGS ALSO INDICATE THAT THE DGZ WILL BE MORE FAVORABLY PLACED
IN THE CONVECTIVE LAYER TO BOOST SLR VALUES AND OVERALL SNOWFALL
POTENTIAL. USING A BLEND OF THE NAM AND LOCAL WRF-ARW QPF WITH
LIKELY CONSERVATIVE SLR VALUES AROUND 20/1...CAME UP WITH TOTAL
SNOWFALL ACCUMULATION EXCEEDING A FOOT OVER ERN ALGER AND NRN LUCE
COUNTIES FOR THE MON NIGHT THROUGH TUE TIME FRAME. THUS...HAVE
DECIDED TO ISSUE A LAKE EFFECT SNOW WATCH FOR ALGER AND LUCE
COUNTIES OVER THIS TIME FRAME. NRN SCHOOLCRAFT WILL LIKELY SEE
PERIODS OF HEAVY LES AS WELL...BUT LOW-LVL CONVERGENCE WILL NOT BE
AS PERSISTENT THERE SO WILL KEEP THEM OUT OF THE WATCH...BUT FEEL
PRETTY CERTAIN THEY WILL EVENTUALLY NEED AN LES ADVISORY.
EVEN THOUGH TEMPS MAY NOT BE AS COLD EARLY TUE...SLIGHTLY STRONGER
WINDS IN THE WAKE OF THE SHORTWAVE WILL AGAIN PUSH WIND CHILLS INTO
THE -25 TO -35 ADVISORY RANGE OVER THE WEST.
WED INTO THU...THE NEXT SIGNIFICANT SHORTWAVE TROUGH IS EXPECTED TO
REMAIN WELL TO THE SOUTH BRINGING SNOW TO MAINLY IA/NRN IL/SRN WI
AND THE SOUTHERN GREAT LAKES. GREAT LAKES AGGREGATE TROUGHING WILL
INFLUENCE GENERALLY LIGHT LOW LEVEL WIND FIELDS AND THE RESULTING LES
INTO UPPER MI AS 850 MB TEMPS REMAIN IN THE -22C TO -26C RANGE. IT
APPEARS NOW THE MAIN FOCUS FOR LES ACCUMULATIONS MAY BE OVER THE
WEST AND NCNTRL PORTIONS OF THE CWA AS A N-NE FLOW IS EXPECTED TO
DEVELOP WED NIGHT INTO THU ON THE BACKSIDE OF SFC LOW PASSING SOUTH
AND THEN EAST OF THE REGION. WITH MODEL SNDGS SHOWING COMPRESSION OF
THE DGZ WITHIN THE LOWEST 2KFT OF THE ATMOSPHERE ALONG WITH
INVERSION HGTS AROUND 5 KFT...THE EXPECTED SMALLER FLAKE SIZE SHOULD
GENERALLY KEEP ACCUMULATION LIGHT FOR THE MOST PART.
FRI-SUN...MODELS WERE IN GENERAL AGREEMENT WITH TREND TOWARD A LESS
AMPLIFIED PATTERN. AS SFC HIGH PRESSURE SLIDES EAST LATE IN THE
WEEK...THE ECMWF AND GFS DEVELOP AREA OF LIGHT SNOW IN REGION OF
WAA/ISENTROPIC ASCENT AHEAD OF A SHRTWV MOVING THROUGH NW ONTARIO.
THIS SNOW LOOKS TO SPREAD INTO UPPER MI LATE FRI INTO SAT MORNING
WITH ANOTHER BAND OF SYNOPTIC SNOW ALONG COLD FRONTAL PASSAGE SAT
AFTERNOON/SAT NIGHT. EXPECT LES TO DEVELOP LATE SATURDAY NIGHT INTO
SUNDAY WITH INCREASING CAA IN NNW FLOW IN THE WAKE OF THE COLD
FRONT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1247 AM EST MON DEC 30 2013
IWD...AS THE LLVL FLOW BACKS SLOWLY TOWARD THE WSW THRU THE NGT...
EXPECT LINGERING -SHSN/CLDS TO SHIFT TO THE N...WITH A TREND TOWARD
PREDOMINANT VFR WX. ALTHOUGH SOME LGT SN IN ADVANCE OF ANOTHER
DISTURBANCE MAY ARRIVE LATE MON AFTN...CONDITIONS ARE LIKELY TO
REMAIN VFR AS THIS SYS WL BE MSTR DEPRIVED AND THE SHARPER DYNAMICS
WL REMAIN TO THE S. A WSHFT TOWARD THE WNW IN ITS WAKE MAY BRING A
RETURN OF LK EFFECT -SHSN AND MVFR CONDITIONS DURING THE EVNG.
CMX...WITH A SLOWLY BACKING NW TO W FLOW OF ARCTIC AIR...EXPECT LK
EFFECT -SHSN AND PREDOMINANT IFR VSBYS TO PERSIST THRU THE FCST
PERIOD. SHARPENING LLVL CNVGC COINCIDENT WITH THE PASSAGE OF A
STRONGER DISTURBANCE/ACCOMPANYING LO PRES TROF PASSAGE MAY BRING A
PERIOD OF HEAVIER SHSN/LIFR CONDITIONS THIS EVNG.
SAW...WITH A DOWNSLOPE W WIND FLOW OF DRY ARCTIC AIR...EXPECT VFR
CONDITIONS TO DOMINATE THIS LOCATION THE ENTIRE FCST PERIOD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 PM EST SUN DEC 29 2013
NORTHWESTERLY WINDS OF 15 TO 25 KNOTS WILL CONTINUE INTO THIS
EVENING BEFORE BACKING TO THE WEST-NORTHWEST LATE TONIGHT INTO
MONDAY. WINDS WILL WEAKEN SLIGHTLY AS THIS OCCURS AND SLOWLY
DIMINISH THE POTENTIAL FOR FREEZING SPRAY OVER THE LAKE BY MONDAY
AFTERNOON. AS THE LINGERING SURFACE TROUGH OVER EASTERN LAKE
SUPERIOR STRENGTHENS ON MONDAY NIGHT AND SHIFTS EAST ON
TUESDAY...NORTHWESTERLY WINDS WILL INCREASE WITH SOME GUSTS TO 30KTS
OVER THE EASTERN LAKE TUESDAY AFTERNOON AND EVENING. THIS WILL ALSO
BRING AN INCREASED OPPORTUNITY FOR HEAVY FREEZING SPRAY THROUGH
TUESDAY NIGHT OVER THE EASTERN HALF OF LAKE SUPERIOR. ALTHOUGH
THERE STILL WILL BE A LINGERING TROUGH OVER EASTERN LAKE SUPERIOR
INTO WEDNESDAY...HIGH PRESSURE BUILDING OVER THE UPPER MISSISSIPPI
VALLEY WILL LEAD TO LIGHTER NORTHWESTERLY WINDS FOR WEDNESDAY AND
THURSDAY...BRINGING AN END TO THE POTENTIAL FOR HEAVY FREEZING
SPRAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL ADVISORY UNTIL 10 AM EST /9 AM CST/ THIS MORNING FOR
MIZ002-009>011-084.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST THIS MORNING FOR MIZ085.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ006-007.
LAKE EFFECT SNOW WATCH FROM THIS EVENING THROUGH TUESDAY EVENING
FOR MIZ006-007.
WIND CHILL ADVISORY FROM 4 AM TO 10 AM EST THIS MORNING FOR
MIZ004-005.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST THIS MORNING FOR
LSZ248>251-264-267.
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST WEDNESDAY FOR LSZ266.
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
LSZ265.
HEAVY FREEZING SPRAY WARNING UNTIL 1 AM EST /MIDNIGHT CST/ EARLY
THIS MORNING FOR LSZ240>245-263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...VOSS
AVIATION...KC
MARINE...SRF
AREA FORECAST DISCUSSION...UPDATED
NWS HASTINGS NE
1153 AM CST MON DEC 30 2013
.UPDATE...
ISSUED AT 1146 AM CST MON DEC 30 2013
UPDATE COMING SHORTLY WITH SOME MINOR TWEAKS. TEMPERATURES
SHOOTING UP PRETTY QUICK WITH WARM FRONTAL/TROF PASSAGE WORKING
EAST ACROSS THE CWFA. HAVE INCREASED TEMPERATURES MOST IN THE
NORTH WITH ORD ALREADY NEAR 40...HOWEVER RAP MODEL SUGGESTS
NEUTRAL/COLD ADVECTION THIS AFTERNOON SO HAVE GONE WITH LOWER
40S AS A HIGHS UP THERE. SLIGHT INCREASES OTHER AREAS AS WELL.
WINDS NEARING ADVISORY IN NORTH CENTRAL NEBRASKA...AND HAVE
INCREASED WIND SPEEDS ACROSS OUR FORECAST AS A RESULT. CLOUDS
ALSO LOOK LESS AND LESS BOTHERSOME. THOUGH A BIT BRISK...TEMPS
10+ DEGREES ABOVE AREN/T TOO BAD FOR DECEMBER 30TH.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 518 AM CST MON DEC 30 2013
UPPER AIR AND SATELLITE DATA SHOW THE REGION UNDER NORTHWESTERLY
FLOW...THANKS TO A LOW PRESSURE SYSTEM OVER THE HUDSON BAY AREA
WITH ITS MAIN TROUGH AXIS EXTENDING SOUTH THROUGH THE CONUS EAST
OF THE MISSOURI RIVER...AND AN AREA OF HIGH PRESSURE SITTING OFF
THE SRN COAST OF CALIFORNIA. A WEAKER PIECE OF SHORTWAVE ENERGY
ASSOCIATED WITH THAT HUDSON BAY LOW IS STARTING TO MAKE ITS WAY
INTO THE REGION FROM THE NW...AND IS CURRENTLY BRINGING PLENTY OF
MID/UPPER LEVEL CLOUD COVER TO THE ENTIRE CWA...AS WELL AS SOME
FLURRIES OR LIGHT SNOW TO NRN PORTIONS OF THE CWA. AT THE
SURFACE...THE CWA SITS BETWEEN HIGH PRESSURE EXTENDING FROM THE
GREAT LAKES TO TX...WITH LOW PRESSURE OVER THE HIGH PLAINS. WINDS
THIS MORNING ARE OUT OF THE SOUTH...AND OCCASIONALLY ON THE GUSTY
SIDE...WHILE WESTERLY WINDS ARE IN PLACE BEHIND A WARM FRONTAL
BOUNDARY OVER WRN NEB.
THE MAIN STORY TODAY LIES WITH THIS DISTURBANCE MOVING
THROUGH...AND THE WARM UP IN TEMPERATURES EXPECTED. THROUGH THE
EARLY/MID MORNING HOURS...WILL CONTINUE TO CARRY THE MENTION OF
SCTRD FLURRIES ACROSS THE NRN HALF OF THE CWA...BUT NO
ACCUMULATION IS EXPECTED WITH ANYTHING THAT DOES FALL. KEPT THE
AFTERNOON HOURS PRECIP FREE...THOUGH THE 4KM WOULD SUGGEST ANOTHER
CHANCE FOR SOME LIGHT PRECIP DIGGING FAR ENOUGH SOUTH TO AFFECT
OUR NORTH AGAIN. ITS BASICALLY THE ONLY MODEL SHOWING THIS SO WILL
KEEP ANY MENTION OUT...BUT WILL BE SOMETHING FOR THE DAY SHIFT TO
MONITOR.
WINDS WILL START TO TURN MORE TO THE SW THEN EVENTUALLY NW BY
MID/LATE MORNING...AND BY MIDDAY THE FRONTAL BOUNDARY IS EXPECTED
TO BE AT LEAST HALFWAY THROUGH THE CWA. W/NW WINDS LOOK TO BE IN
PLACE ACROSS THE ENTIRE CWA BY MID AFTERNOON...WITH SUSTAINED
SPEEDS IN THE 15 TO 25 MPH RANGE AND GUSTS OVER 30 MPH
EXPECTED...WITH THE STRONGER WINDS ACROSS THE W/NWRN HALF OF THE
CWA.
LOOKING AT TEMPERATURES...AS EXPECTED TEMPS OVERNIGHT HAVE BEEN
STEADY/ON THE INCREASE AS WARMER AIR ALOFT IS GRADUALLY ADVECTING
INTO THE AREA...A TREND WHICH WILL CONTINUE INTO THE DAYTIME
HOURS. ALONG WITH THE DOWNSLOPING COMPONENT OF THE W/NWRLY
WINDS...WILL SEE A NICE BUMP UP IN TEMPERATURES COMPARED TO
SUNDAY...WITH SOME LOCATIONS LOOKING TO BE 20+ DEGREES WARMER.
KEPT TEMPS TRENDED TOWARD THE RAP/HRRR...AND THE FORECAST CALLS
FOR LOWER 40S IN THE FAR NRN CWA...WITH NEAR 50 IN THE
ROOKS/PHILLIPS COUNTY KS AREA.
THIS EVENING/TONIGHT REMAINS DRY...WITH SURFACE HIGH PRESSURE
SETTLING INTO THE AREA...BRINGING DIMINISHING WINDS BEFORE
SWITCHING TO THE SOUTH ONCE AGAIN TOWARD 12Z. SHOULD CONTINUE TO
SEE A FEW CLOUDS AROUND THE AREA...WITH OVERNIGHT LOWS EXPECTED TO
FALL INTO THE MID/UPPER TEENS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 518 AM CST MON DEC 30 2013
THE BIGGEST CHALLENGES WILL BE DETERMINING THE TIMING AND
PLACEMENT OF A SURFACE FRONT ON TUESDAY AND HOW FAR SOUTHWEST
COLD AIR MAKES IT BY WEDNESDAY. ALSO A CHALLENGE IS DETERMINING
CHANCE OF PRECIPITATION CHANCES AND TYPE FOR WEDNESDAY.
WE BEGIN THE LONG TERM TUESDAY UNDER NORTHWEST FLOW...BETWEEN A
MID-LEVEL CLOSED LOW OVER SOUTHERN HUDSON BAY AND A CLOSED LOW
OVER WESTERN MEXICO. HIGH TEMPERATURES COULD BE
TRICKY...DEPENDING ON WHERE A SURFACE FRONT ENDS UP TUESDAY. FOR
NOW...IT APPEARS THAT PERHAPS ONLY THE EXTREME NORTHEASTERN CWA
WILL FAIL TO CLIMB TO MILD TEMPERATURES FOR THIS TIME OF
YEAR...JUDGING BY SOLUTIONS WITH THE MOST CONSISTENCY.
A WAVE WILL MOVE INTO THE NORTHWESTERN UNITED STATES WITH AN
ASSOCIATED JET DIVING SOUTH ON THE WEST SIDE OF THE TROUGH. THE
AXIS OF THIS DIGGING TROUGH WILL ENTER THE CENTRAL PLAINS ON
WEDNESDAY...WITH THE TROUGH CROSSING THE CWA NEAR 00Z THURSDAY.
PRECIPITATION COULD START AS EARLY AS LATE TUESDAY NIGHT AND LAST
INTO MOST OF THE DAY ON WEDNESDAY...AT LEAST UNTIL THE TROUGH AXIS
CLEARS THE CWA AT THE END OF THE DAY. THERE ARE SOME MODEL
SOLUTIONS THAT INDICATE THERE MAY BE A WARM NOSE OF AIR ABOVE THE
SURFACE THAT COULD GIVE US SOME POTENTIAL FOR FREEZING RAIN/SLEET
AT THE ONSET OF PRECIPITATION. I AM NOT VERY CONFIDENT WITH THIS
PRECIPITATION TYPE AND HAVE KEPT THIS OUT OF THE FORECAST AS THERE
IS DEFINITELY NOT ANY SORT OF WIDESPREAD AGREEMENT HERE. WAS
RELUCTANT TO GO TOO COLD IN THE SOUTHWEST FOR WEDNESDAY...UNSURE
OF HOW MUCH OF A DOWNSLOPE COMPONENT TO THE WIND WILL HOLD ON
BEFORE THE WIND NUDGES FROM NORTHWEST TO NORTH. ACTUALLY RAISED
TEMPERATURES IN THE SOUTHWESTERN CWA COMPARED TO THE PREVIOUS
FORECAST...DESPITE A COLD FRONT MOVING SOUTH WITH THE MID-UPPER
LEVEL TROUGH ENTERING OUR REALM. I ALSO INCREASED WIND SPEEDS
BEHIND THE FRONT WEDNESDAY...AS THE SURFACE PRESSURE GRADIENT WILL
BE QUITE STRONG. I RAISED CHANCES OF PRECIPITATION FOR WEDNESDAY A
BIT...ESPECIALLY IN THE NORTHEAST AS MODELS ARE A BIT MORE
CONSISTENT WITH GETTING SOME PRECIPITATION...ESPECIALLY IN THE
NORTHEAST. LOWERED LOW TEMPERATURES FOR THURSDAY MORNING A BIT FOR
SOME AREAS AS WIND SPEEDS DIMINISH...ESPECIALLY IN THE WEST. IN
OUR EAST...WIND SPEEDS MIGHT BE UP JUST ENOUGH TO ALLOW OUR FAR
NORTHEASTERN TIP OF THE CWA TO BE IN OR NEAR POTENTIAL WIND CHILL
CONCERNS...BUT QUITE ENOUGH OF AN AREA TO INCLUDE THIS POTENTIAL
FOR WHAT LOOKS VERY MARGINAL AT BEST AS IT IS.
A RIDGE QUICKLY THEN MAKES OUR TEMPERATURES RELATIVELY MILD FOR
THURSDAY AND FRIDAY BEFORE ANOTHER SHOT AIR MOVES IN FOR THE
WEEKEND WITH AN EVEN DEEPER AND LONGER WAVELENGTH THAN THE ONE
COMING MID-WEEK. THERE COULD BE ANOTHER SHOT AT SOME
PRECIPITATION...MOST LIKELY SOME LIGHT SNOW.
AS FOR SNOW AMOUNTS FOR MID-WEEK...NOTHING INDICATES HUGE
NUMBERS...AND NOTHING ABOVE AN INCH AS OF YET AS THERE WILL NOT BE
A LOT OF MOISTURE TO WORK WITH.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1146 AM CST MON DEC 30 2013
VFR CONDITIONS ARE FORECAST FOR THE KGRI AREA. SOME MID CLOUDS
EARLY ON IN THE FORECAST WILL SCATTERED OUT BY EVENING. HOWEVER
MVFR CEILINGS APPEAR AS THOUGH THEY WILL RETURN OVERNIGHT WITH
A SOUTH/SOUTHEAST FLOW RETURNING. WINDS WILL BE INCREASING
QUICKLY EARLY THIS AFTERNOON WITH 20-30KT NORTHWEST WINDS
THE REST OF THE AFTERNOON. NO VISIBILITY RESTRICTIONS ARE
EXPECTED...AND WINDS WILL QUICKLY DIE BETWEEN SUNSET AND
MID EVENING.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...NOAA/NWS/MORITZ
SHORT TERM...ADO
LONG TERM...HEINLEIN
AVIATION...NOAA/NWS/MORITZ
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
137 AM EST MON DEC 30 2013
.SYNOPSIS...
SURFACE LOW PRESSURE WILL MOVE INTO NEW ENGLAND TONIGHT AND INTO
EASTERN CANADA BY MONDAY...WHILE A SHARP ARCTIC COLD FRONT PUSHES
ACROSS THE NORTH COUNTRY ON MONDAY MORNING. A MIX OF RAIN AND SNOW
WILL GRADUALLY END TONIGHT WITH SOME MODERATE SNOW ACCUMULATION
LIKELY ACROSS THE HIGHER TERRAIN OF CENTRAL AND SOUTHERN VERMONT.
ADDITIONAL SNOW SHOWERS WILL BE POSSIBLE ASSOCIATED WITH THE
ARCTIC BOUNDARY ON MONDAY MORNING...WITH A FLASH FREEZE
LIKELY...CREATING A HAZARDOUS COMMUTE.
&&
.NEAR TERM /UNTIL 10 AM THIS MORNING/...
AS OF 1221 AM EST MONDAY...CANCELLED ALL ADVISORIES/WARNINGS AS
STEADY PRECIPITATION HAS RAPIDLY EXITED THE REGION. SNOW/ICE
REPORTS ARE AVAILABLE IN PUBLIC INFORMATION STATEMENT. SOME FOG
HAS DEVELOPED IN THE WAKE OF THE DEPARTING PRECIP...AND THIS WILL
CONTINUE UNTIL SCOURED OUT BY THE PASSAGE OF THE ARCTIC FRONT
LATER TONIGHT. STILL LOOKING AT A BRIEF PERIOD OF SNOW SHOWERS AS
THE FRONT CROSSES THE REGION...WITH PERHAPS A SMALL WINDOW FOR
SOME UPSLOPE ENHANCEMENT IN THE MOUNTAINS...BUT THE ATMOSPHERE
DRIES OUT QUICKLY MONDAY MORNING...SO ONLY A DUSTING-2" EXPECTED
AT MOST. WILL SEE TEMPERATURES DROP FROM THE LOW 30S THROUGH THE
20S AND INTO THE TEENS QUITE RAPIDLY MONDAY MORNING SO A QUICK
FREEZE-UP OF ANY RESIDUAL WATER OR SLUSH IS POSSIBLE.
PREVIOUS DISCUSSION FROM 922 PM SUNDAY...
QUICK HITTING WINTER STORM NOW WINDING DOWN ACROSS THE REGION AS
STRENGTHENING LOW PRESSURE CENTERED NEAR NANTUCKET MOVES
NORTHEASTWARD OVER CAPE COD AND TO A POSITION OVER NOVA SCOTIA BY
MONDAY MORNING. HEAVIEST PRECIPITATION NOW OVER SOUTHEASTERN
VERMONT WITH LIGHT-MODERATE PRECIP STILL BACK INTO THE CHAMPLAIN
VALLEY. BACK EDGE HAS CLEARED PLATTSBURGH AND WILL PUSH THROUGH
BURLINGTON WITHIN THE HOUR. PRECIP WILL TAPER OFF FAIRLY QUICKLY
OVER THE NEXT 2-3 HOURS FOR ENTIRE REGION. MOST PRECIP HAS FALLEN
AS SNOW WHERE IT HAS BEEN HEAVY DUE TO DYNAMIC COOLING...AT RATES
OF 1-3 INCHES PER HOUR IN SE VT. REPORTS ACROSS SOUTHERN AND
EASTERN VERMONT GENERALLY RANGE BETWEEN 3 AND 9 INCHES SO FAR.
HOWEVER...WHERE IT HAS REMAINED LIGHTER ALLOWING THE WARM BOUNDARY
LAYER TO HANG ON...IT HAS BEEN IN THE FORM OF A RAIN/SNOW MIX. LOW
LEVEL COLD AIR HAD ALSO SUNK SOUTHWARD INTO THE CHAMPLAIN
VALLEY...DELIVERING LIGHT FREEZING RAIN/SLEET (FROM BTV NORTHWARD)
WITH WARM LAYER STILL REMAINING AT AROUND 925-MB. LOCAL BTV WRF
AND HRRR MODELS HANDLING THERMAL PROFILES AND DEPICTION OF
PRECIPITATION THE BEST SO HAVE LEANED HEAVILY TOWARDS THEM FOR THE
REST OF TONIGHT.
ARCTIC FRONT THEN BRINGS AN ADDITIONAL CHANCE OF SNOW SHOWERS
TOWARDS MORNING...WITH RAPIDLY FALLING TEMPERATURES AND THREAT OF
FREEZING WATER/SLUSH ON ROADWAYS.
TOTALS GENERALLY 4-8" LOCALLY 10" IN ORANGE/WINDSOR/EASTERN RUTLAND
COUNTIES...DUSTING-4" HIGHLY DEPENDENT ON PRECIP INTENSITY AND
ELEVATION ACROSS MUCH OF THE REST OF VERMONT OUTSIDE OF THE
CHAMPLAIN VALLEY...AND A DUSTING-2" ELSEWHERE. ICE ACCUMULATIONS
IN THE CPV GENERALLY A FEW HUNDRETHS...ENOUGH TO CAUSE HAZARDOUS
TRAVEL AND ACCIDENTS.
&&
.SHORT TERM /10 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 322 PM EST SUNDAY...WITH UPSLOPE SNOW SHOWERS ACROSS THE
HIGHER TERRAIN EFFECTIVELY COMING TO AN END EARLY MONDAY
NIGHT...THE FOCUS THEN SHIFTS TO A PERIOD OF VERY COLD
TEMPERATURES BEGINNING MONDAY NIGHT AND CONTINUING INTO THE FIRST
FEW DAYS OF 2014.
ARCTIC COLD FRONT MOVES ACROSS THE REST OF THE NORTH COUNTRY EARLY
MONDAY NIGHT ALLOWING FOR 850 TEMPS TO FALL TO AROUND -16 TO -18C.
WITH DEEP-LAYER DRYING TAKING PLACE AS HIGH PRESSURE BUILDS INTO THE
REGION OVERNIGHT TEMPERATURES MONDAY WILL BE QUITE COLD. ASIDE FROM
SOUTHERN VERMONT...MOST LOCATIONS WILL SEE LOWS THAT ARE BELOW ZERO
EVEN IN THE CHAMPLAIN VALLEY. I THINK THE COLDEST SPOT MONDAY NIGHT
WILL BE IN THE NORTHEAST KINGDOM AS THAT AREA IS FURTHEST REMOVED
FROM MID-LEVEL WARM ADVECTION CLOUDINESS WHICH IS PROJECTED TO SPILL
INTO NORTHERN NEW YORK LATE MONDAY NIGHT.
INCREASING CLOUDS THEN SPREAD ACROSS THE REST OF THE NORTH COUNTRY
TUESDAY AHEAD OF A MOISTURE-STARVED CLIPPER SYSTEM. DESPITE THE
FACT THAT MOISTURE WILL BE LIMITED WITH THE CLIPPER...ACCOMPANYING
ISENTROPIC LIFT AND RATHER HIGH SNOW/LIQUID RATIOS (15-20:1) DUE TO
COLD AIRMASS IN PLACE SHOULD ALLOW FOR AT LEAST A MODEST POWDERY
SNOW ACCUMULATION OF 1-3". THE ASSOCIATED COLD FRONT WILL THEN
USHER IN ANOTHER SHOT OF EVEN COLDER AIR TUESDAY NIGHT. NORTHWEST
WINDS WILL ALSO BE IN THE 15 TO 20 MPH RANGE WITH GUSTS TO 30 MPH
AS WELL FROM STRONGER MIXING. IT WOULDN`T BE SURPRISING IF SOME
LOCALES IN THE NORTHEAST KINGDOM AND NORTHERN NEW YORK HIT WIND
CHILL ADVISORY CRITERIA...WHICH WILL NEED TO BE MONITORED WITH LATER
SHIFTS. LOWS TUESDAY NIGHT MAY BE A FEW DEGREES WARMER THAN MONDAY
NIGHT (RANGING FROM THE LOWER SINGLE DIGITS TO 10 BELOW ZERO)...BUT
IT CERTAINLY WON`T FEEL THAT WAY GIVEN THE WINDS.
A RIDGE OF ARCTIC HIGH PRESSURE WILL EXTEND ACROSS THE NORTHERN
HALF OF THE NORTH COUNTRY ON WEDNESDAY...SEPERATING A DEVELOPING
EAST-WEST WARM FRONTAL BOUNDARY EXTENDING FROM A DISTURBANCE IN THE
GREAT LAKES. THE NORTH COUNTRY REMAINS ON THE COLD SIDE OF THIS
BOUNDARY THROUGHOUT WEDNESDAY...AND HAVE SHOWN INCREASING POPS FROM
SOUTH TO NORTH WEDNESDAY INTO WEDNESDAY NIGHT. I DO THINK THAT
THERE WILL PROBABLY BE A SHARP NORTH-SOUTH GRADIENT IN
PRECIPITATION GIVEN THE INFLUENCE OF THE ARCTIC HIGH WITH THE
HIGHEST POPS (CHANCE) CONFINED TO CENTRAL AND SOUTHERN VERMONT.
TEMPERATURES REMAIN COLD WITH HIGHS IN THE SINGLE DIGITS TO LOW
TEENS AND LOWS 0 TO 15 BELOW (COLDEST NORTH).
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 322 PM EST SUNDAY...CONSISTENCY IS GOOD AMONGST GLOBAL
MODELS INTO THURSDAY WITH SOME DIFFERENCES IN POSITION AND TRACK
OF A POTENTIAL COASTAL SYSTEM APPROACHING SOUTHERN NEW ENGLAND AND
ADJACENT COASTAL WATERS. THEME OF COLD TEMPERATURES CONTINUES
EARLY IN THIS PERIOD WITH AN INCREASING TREND TOWARD MORE ACTIVE
WEATHER FOR LATE IN THE WEEK.
LIGHT SNOWS SHOULD BE ONGOING TO OPEN THE EXTENDED WITH THE NORTH
COUNTRY ON THE NORTHERN SIDE OF A QUASI-STATIONARY BOUNDARY OVER
CENTRAL/SOUTHERN NEW ENGLAND. MEANWHILE...A MID-LEVEL SHORTWAVE
TROUGH MOVING ACROSS THE LOWER OHIO VALLEY WILL HELP TO ENERGIZE A
DEVELOPING COASTAL LOW NEAR THE CHESAPEAKE BAY AREA EARLY THURSDAY
MORNING. THE GFS TAKES THE DEVELOPING COASTAL NEAR OR JUST
SOUTHEAST OF THE 40N/70W BENCHMARK...WHILE THE ECMWF IS STRONGER
AND DECIDEDLY MORE INSIDE THE BENCHMARK. THOUGH BOTH MODELS SHOW A
DIFFERING CENTER TRACK...THE SOLUTIONS ARE AT LEAST CONSISTENT WITH
THEIR PRIOR COUPLE OF RUNS. BOTH GFS AND ECMWF SHOW A GOOD EASTERN
UPSLOPE PRECIPITATION ENHANCEMENT SIGNATURE AND HAVE SHOWN THE
HIGHEST POPS (LOW LIKELY) TOWARD THE EAST-FACING SLOPE AREAS FOR
THURSDAY NIGHT. LINGERING SNOWS CONTINUE INTO EARLY FRIDAY BEFORE
TAPERING THEREAFTER. IT`S STILL A LITTLE EARLY TO PROJECT SNOW
AMOUNTS WITH MORE SPECIFIC DETAILS WHICH STILL BE IRONED OUT...BUT
IT`S PROBABLY FAIR TO SAY THAT THERE WOULD BE SOME POTENTIAL IMPACT
FROM THIS COASTAL FOR THE NORTH COUNTRY. HIGHS THURSDAY AND FRIDAY
WILL STAY IN THE SINGLE DIGITS.
A LARGE-AMPLITUDE UPPER-LEVEL TROUGH THEN LINGERS OVER THE NORTH
COUNTRY FRIDAY NIGHT INTO SATURDAY WHICH WILL MAINTAIN CONTINUED
BITTER COLD. 850 TEMPS OF -24 TO -26C ALONG WITH AT LEAST PARTLY
CLOUDY SKIES SHOULD RESULT IN LOWS FRIDAY NIGHT AROUND -8 TO -16
BELOW. SOME INDICATION BY LATER IN THE WEEKEND THAT THE VERY COLD
TEMPERATURES FINALLY BEGIN TO MODERATE.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
THROUGH 06Z TUESDAY...THE LOW PRESSURE AREA THAT BROUGHT
RAIN...FREEZING RAIN AND SNOW TO THE REGION SUNDAY NIGHT IS NOW
OVER WESTERN NOVA SCOTIA AT 06Z MONDAY. PRECIPITATION ACROSS THE REGION
HAS ENDED FOR THE MOST PART...WITH MAINLY FOG/MIST AND POCKETS OF
FREEZING DRIZZLE AT 06Z MONDAY. IFR/MVFR CEILINGS/VISIBILITIES
WILL IMPROVE TO VFR BY 18Z MONDAY WITH CLEARING SKIES DEVELOPING
ACROSS THE REGION AS A SURFACE RIDGE OF HIGH PRESSURE BUILDS
SOUTHEAST FROM CANADA. THIS HIGH PRESSURE AREA WILL BE CENTERED
OVER THE REGION BY 06Z TUESDAY.
OUTLOOK 06Z TUESDAY THROUGH FRIDAY...
06Z TUESDAY-12Z TUESDAY...VFR WITH LIGHT WINDS WITH ARCTIC AIR.
TUE...BECMG IFR IN PM LIGHT SNOW WITH LOW PRESSURE CLIPPER SYSTEM.
WED...MAINLY VFR UNDER ARCTIC HIGH PRESSURE.
THU-FRI...BECMG IFR IN SNOW WITH LOW PRESSURE OFF THE COAST.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...TABER
NEAR TERM...MUCCILLI
SHORT TERM...LOCONTO
LONG TERM...LOCONTO
AVIATION...WGH/SISSON
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1229 AM EST MON DEC 30 2013
.SYNOPSIS...
SURFACE LOW PRESSURE WILL MOVE INTO NEW ENGLAND TONIGHT AND INTO
EASTERN CANADA BY MONDAY...WHILE A SHARP ARCTIC COLD FRONT PUSHES
ACROSS THE NORTH COUNTRY ON MONDAY MORNING. A MIX OF RAIN AND SNOW
WILL GRADUALLY END TONIGHT WITH SOME MODERATE SNOW ACCUMULATION
LIKELY ACROSS THE HIGHER TERRAIN OF CENTRAL AND SOUTHERN VERMONT.
ADDITIONAL SNOW SHOWERS WILL BE POSSIBLE ASSOCIATED WITH THE
ARCTIC BOUNDARY ON MONDAY MORNING...WITH A FLASH FREEZE
LIKELY...CREATING A HAZARDOUS COMMUTE.
&&
.NEAR TERM /UNTIL 10 AM THIS MORNING/...
AS OF 1221 AM EST MONDAY...CANCELLED ALL ADVISORIES/WARNINGS AS
STEADY PRECIPITATION HAS RAPIDLY EXITED THE REGION. SNOW/ICE
REPORTS ARE AVAILABLE IN PUBLIC INFORMATION STATEMENT. SOME FOG
HAS DEVELOPED IN THE WAKE OF THE DEPARTING PRECIP...AND THIS WILL
CONTINUE UNTIL SCOURED OUT BY THE PASSAGE OF THE ARCTIC FRONT
LATER TONIGHT. STILL LOOKING AT A BRIEF PERIOD OF SNOW SHOWERS AS
THE FRONT CROSSES THE REGION...WITH PERHAPS A SMALL WINDOW FOR
SOME UPSLOPE ENHANCEMENT IN THE MOUNTAINS...BUT THE ATMOSPHERE
DRIES OUT QUICKLY MONDAY MORNING...SO ONLY A DUSTING-2" EXPECTED
AT MOST. WILL SEE TEMPERATURES DROP FROM THE LOW 30S THROUGH THE
20S AND INTO THE TEENS QUITE RAPIDLY MONDAY MORNING SO A QUICK
FREEZE-UP OF ANY RESIDUAL WATER OR SLUSH IS POSSIBLE.
PREVIOUS DISCUSSION FROM 922 PM SUNDAY...
QUICK HITTING WINTER STORM NOW WINDING DOWN ACROSS THE REGION AS
STRENGTHENING LOW PRESSURE CENTERED NEAR NANTUCKET MOVES
NORTHEASTWARD OVER CAPE COD AND TO A POSITION OVER NOVA SCOTIA BY
MONDAY MORNING. HEAVIEST PRECIPITATION NOW OVER SOUTHEASTERN
VERMONT WITH LIGHT-MODERATE PRECIP STILL BACK INTO THE CHAMPLAIN
VALLEY. BACK EDGE HAS CLEARED PLATTSBURGH AND WILL PUSH THROUGH
BURLINGTON WITHIN THE HOUR. PRECIP WILL TAPER OFF FAIRLY QUICKLY
OVER THE NEXT 2-3 HOURS FOR ENTIRE REGION. MOST PRECIP HAS FALLEN
AS SNOW WHERE IT HAS BEEN HEAVY DUE TO DYNAMIC COOLING...AT RATES
OF 1-3 INCHES PER HOUR IN SE VT. REPORTS ACROSS SOUTHERN AND
EASTERN VERMONT GENERALLY RANGE BETWEEN 3 AND 9 INCHES SO FAR.
HOWEVER...WHERE IT HAS REMAINED LIGHTER ALLOWING THE WARM BOUNDARY
LAYER TO HANG ON...IT HAS BEEN IN THE FORM OF A RAIN/SNOW MIX. LOW
LEVEL COLD AIR HAD ALSO SUNK SOUTHWARD INTO THE CHAMPLAIN
VALLEY...DELIVERING LIGHT FREEZING RAIN/SLEET (FROM BTV NORTHWARD)
WITH WARM LAYER STILL REMAINING AT AROUND 925-MB. LOCAL BTV WRF
AND HRRR MODELS HANDLING THERMAL PROFILES AND DEPICTION OF
PRECIPITATION THE BEST SO HAVE LEANED HEAVILY TOWARDS THEM FOR THE
REST OF TONIGHT.
ARCTIC FRONT THEN BRINGS AN ADDITIONAL CHANCE OF SNOW SHOWERS
TOWARDS MORNING...WITH RAPIDLY FALLING TEMPERATURES AND THREAT OF
FREEZING WATER/SLUSH ON ROADWAYS.
TOTALS GENERALLY 4-8" LOCALLY 10" IN ORANGE/WINDSOR/EASTERN RUTLAND
COUNTIES...DUSTING-4" HIGHLY DEPENDENT ON PRECIP INTENSITY AND
ELEVATION ACROSS MUCH OF THE REST OF VERMONT OUTSIDE OF THE
CHAMPLAIN VALLEY...AND A DUSTING-2" ELSEWHERE. ICE ACCUMULATIONS
IN THE CPV GENERALLY A FEW HUNDRETHS...ENOUGH TO CAUSE HAZARDOUS
TRAVEL AND ACCIDENTS.
&&
.SHORT TERM /10 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 322 PM EST SUNDAY...WITH UPSLOPE SNOW SHOWERS ACROSS THE
HIGHER TERRAIN EFFECTIVELY COMING TO AN END EARLY MONDAY
NIGHT...THE FOCUS THEN SHIFTS TO A PERIOD OF VERY COLD
TEMPERATURES BEGINNING MONDAY NIGHT AND CONTINUING INTO THE FIRST
FEW DAYS OF 2014.
ARCTIC COLD FRONT MOVES ACROSS THE REST OF THE NORTH COUNTRY EARLY
MONDAY NIGHT ALLOWING FOR 850 TEMPS TO FALL TO AROUND -16 TO -18C.
WITH DEEP-LAYER DRYING TAKING PLACE AS HIGH PRESSURE BUILDS INTO THE
REGION OVERNIGHT TEMPERATURES MONDAY WILL BE QUITE COLD. ASIDE FROM
SOUTHERN VERMONT...MOST LOCATIONS WILL SEE LOWS THAT ARE BELOW ZERO
EVEN IN THE CHAMPLAIN VALLEY. I THINK THE COLDEST SPOT MONDAY NIGHT
WILL BE IN THE NORTHEAST KINGDOM AS THAT AREA IS FURTHEST REMOVED
FROM MID-LEVEL WARM ADVECTION CLOUDINESS WHICH IS PROJECTED TO SPILL
INTO NORTHERN NEW YORK LATE MONDAY NIGHT.
INCREASING CLOUDS THEN SPREAD ACROSS THE REST OF THE NORTH COUNTRY
TUESDAY AHEAD OF A MOISTURE-STARVED CLIPPER SYSTEM. DESPITE THE
FACT THAT MOISTURE WILL BE LIMITED WITH THE CLIPPER...ACCOMPANYING
ISENTROPIC LIFT AND RATHER HIGH SNOW/LIQUID RATIOS (15-20:1) DUE TO
COLD AIRMASS IN PLACE SHOULD ALLOW FOR AT LEAST A MODEST POWDERY
SNOW ACCUMULATION OF 1-3". THE ASSOCIATED COLD FRONT WILL THEN
USHER IN ANOTHER SHOT OF EVEN COLDER AIR TUESDAY NIGHT. NORTHWEST
WINDS WILL ALSO BE IN THE 15 TO 20 MPH RANGE WITH GUSTS TO 30 MPH
AS WELL FROM STRONGER MIXING. IT WOULDN`T BE SURPRISING IF SOME
LOCALES IN THE NORTHEAST KINGDOM AND NORTHERN NEW YORK HIT WIND
CHILL ADVISORY CRITERIA...WHICH WILL NEED TO BE MONITORED WITH LATER
SHIFTS. LOWS TUESDAY NIGHT MAY BE A FEW DEGREES WARMER THAN MONDAY
NIGHT (RANGING FROM THE LOWER SINGLE DIGITS TO 10 BELOW ZERO)...BUT
IT CERTAINLY WON`T FEEL THAT WAY GIVEN THE WINDS.
A RIDGE OF ARCTIC HIGH PRESSURE WILL EXTEND ACROSS THE NORTHERN
HALF OF THE NORTH COUNTRY ON WEDNESDAY...SEPERATING A DEVELOPING
EAST-WEST WARM FRONTAL BOUNDARY EXTENDING FROM A DISTURBANCE IN THE
GREAT LAKES. THE NORTH COUNTRY REMAINS ON THE COLD SIDE OF THIS
BOUNDARY THROUGHOUT WEDNESDAY...AND HAVE SHOWN INCREASING POPS FROM
SOUTH TO NORTH WEDNESDAY INTO WEDNESDAY NIGHT. I DO THINK THAT
THERE WILL PROBABLY BE A SHARP NORTH-SOUTH GRADIENT IN
PRECIPITATION GIVEN THE INFLUENCE OF THE ARCTIC HIGH WITH THE
HIGHEST POPS (CHANCE) CONFINED TO CENTRAL AND SOUTHERN VERMONT.
TEMPERATURES REMAIN COLD WITH HIGHS IN THE SINGLE DIGITS TO LOW
TEENS AND LOWS 0 TO 15 BELOW (COLDEST NORTH).
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 322 PM EST SUNDAY...CONSISTENCY IS GOOD AMONGST GLOBAL
MODELS INTO THURSDAY WITH SOME DIFFERENCES IN POSITION AND TRACK
OF A POTENTIAL COASTAL SYSTEM APPROACHING SOUTHERN NEW ENGLAND AND
ADJACENT COASTAL WATERS. THEME OF COLD TEMPERATURES CONTINUES
EARLY IN THIS PERIOD WITH AN INCREASING TREND TOWARD MORE ACTIVE
WEATHER FOR LATE IN THE WEEK.
LIGHT SNOWS SHOULD BE ONGOING TO OPEN THE EXTENDED WITH THE NORTH
COUNTRY ON THE NORTHERN SIDE OF A QUASI-STATIONARY BOUNDARY OVER
CENTRAL/SOUTHERN NEW ENGLAND. MEANWHILE...A MID-LEVEL SHORTWAVE
TROUGH MOVING ACROSS THE LOWER OHIO VALLEY WILL HELP TO ENERGIZE A
DEVELOPING COASTAL LOW NEAR THE CHESAPEAKE BAY AREA EARLY THURSDAY
MORNING. THE GFS TAKES THE DEVELOPING COASTAL NEAR OR JUST
SOUTHEAST OF THE 40N/70W BENCHMARK...WHILE THE ECMWF IS STRONGER
AND DECIDEDLY MORE INSIDE THE BENCHMARK. THOUGH BOTH MODELS SHOW A
DIFFERING CENTER TRACK...THE SOLUTIONS ARE AT LEAST CONSISTENT WITH
THEIR PRIOR COUPLE OF RUNS. BOTH GFS AND ECMWF SHOW A GOOD EASTERN
UPSLOPE PRECIPITATION ENHANCEMENT SIGNATURE AND HAVE SHOWN THE
HIGHEST POPS (LOW LIKELY) TOWARD THE EAST-FACING SLOPE AREAS FOR
THURSDAY NIGHT. LINGERING SNOWS CONTINUE INTO EARLY FRIDAY BEFORE
TAPERING THEREAFTER. IT`S STILL A LITTLE EARLY TO PROJECT SNOW
AMOUNTS WITH MORE SPECIFIC DETAILS WHICH STILL BE IRONED OUT...BUT
IT`S PROBABLY FAIR TO SAY THAT THERE WOULD BE SOME POTENTIAL IMPACT
FROM THIS COASTAL FOR THE NORTH COUNTRY. HIGHS THURSDAY AND FRIDAY
WILL STAY IN THE SINGLE DIGITS.
A LARGE-AMPLITUDE UPPER-LEVEL TROUGH THEN LINGERS OVER THE NORTH
COUNTRY FRIDAY NIGHT INTO SATURDAY WHICH WILL MAINTAIN CONTINUED
BITTER COLD. 850 TEMPS OF -24 TO -26C ALONG WITH AT LEAST PARTLY
CLOUDY SKIES SHOULD RESULT IN LOWS FRIDAY NIGHT AROUND -8 TO -16
BELOW. SOME INDICATION BY LATER IN THE WEEKEND THAT THE VERY COLD
TEMPERATURES FINALLY BEGIN TO MODERATE.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
THROUGH 18Z MONDAY...IFR/MVFR AS LOW PRESSURE TRACKS ACROSS
SOUTHEAST NEW ENGLAND BY MIDNIGHT AND WITH ARCTIC FRONT DRAPED
KMSS-KBTV.
PRECIPITATION TYPE IS TRICKY AS CURRENT TEMPS RANGING FROM 25 AT
KMSS TO ABOUT FREEZING OTHER SITES. MIXED PRECIP AT KBTV/KPBG/KSLK
AND SNOW AT KRUT/KMPV AND COMING DOWN MODERATLY. THIS WILL BE A QUICK
HITTER AS PRECIP TAPERS OFF BY AROUND MIDNIGHT LEAVING SOME
RESIDUAL -DZ -FZDZ DEPENDING UPON TEMPS WHICH WILL BE EITHER SIDE
OF 32.
EARLY TOMORROW MORNING, BASICALLY 06Z KMSS TO 09Z KBTV TO 11Z
KRUT/MPV, ARCTIC FRONTAL PASSAGE EXPECTED WITH SCATTERED BRIEF
HEAVIER SNOW SHOWER OR TWO, MOST PERSISTENT IN THE HIGHER
ELEVATIONS. TEMPS WILL FALL 20 DEGREES IN A COUPLE HOURS AND WINDS
WILL GUST AS HIGH AS 25 KTS PERHAPS 30KT SO WILL BE A QUICK ICE UP
OF RUNWAYS AND SOME DRIFTING.
EXPECTING IMPROVING CONDITIONS 15-21Z AS DRIER AIR MOVES IN AND
WINDS SETTLE DOWN SOMEWHAT.
OUTLOOK 00Z TUESDAY THROUGH FRIDAY...
MON NIGHT...VFR WITH LIGHT WINDSWITH ARCTIC AIR.
TUE...BECMG IFR IN PM LIGHT SNOW WITH LOW PRESSURE CLIPPER
SYSTEM.
WED...MAINLY VFR UNDER ARCTIC HIGH PRESSURE.
THU-FRI...BECMG IFR IN SNOW WITH LOW PRESSURE OFF THE COAST.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...TABER
NEAR TERM...MUCCILLI
SHORT TERM...LOCONTO
LONG TERM...LOCONTO
AVIATION...SISSON
AREA FORECAST DISCUSSION
NWS BISMARCK ND
935 PM CST TUE DEC 31 2013
.UPDATE...
ISSUED AT 934 PM CST TUE DEC 31 2013
LIGHT SNOW CONTINUES TO DISSIPATE AS IT MOVES EAST ACROSS CENTRAL
NORTH DAKOTA. UPDATED POPS BASED ON LATEST RADAR TRENDS...KEEPING
HIGHER CHANCE TO LIKELY POPS FROM AROUND THE HARVEY AREA SOUTHEAST
THROUGH ELLENDALE THROUGH 06 UTC...THEN CHANCE POPS DIMINISHING TO
SLIGHT CHANCE OVER EASTERN PORTIONS OF THE CWA THROUGH MID MORNING
WEDNESDAY. IN THE WEST...KNOCKED BACK POPS TO SLIGHT CHANCE
THROUGH AROUND 08 UTC. THEN BROUGHT A CHANCE OF LIGHT SNOW TO THE
FAR SOUTHWEST FROM 08-15 UTC. LATEST RAP AND HRRR MESOSCALE MODELS
AND THE NEW 01 JAN 14 00 UTC NAM CLIP THE SOUTHWEST WITH LIGHT QPF
ASSOCIATED WITH ANOTHER IMPULSE CURRENTLY DROPPING FORM
ALBERTA/SASKATCHEWAN INTO NORTH CENTRAL MONTANA. WILL CANCEL THE
REMAINING PORTION OF THE WINTER WEATHER ADVISORY. ANY ADDITIONAL
SNOWFALL TONIGHT IS EXPECTED TO BE LIGHT AND WILL NOT ARRIVE UNTIL
THE CURRENT HAZARD ENDS.
UPDATE ISSUED AT 627 PM CST TUE DEC 31 2013
LATEST SATELLITE SHOWS AN IMPULSE MOVING FROM NORTHEAST MONTANA
INTO WESTERN NORTH DAKOTA. LIGHT SNOW CONTINUES TO FALL OVER FAR
SOUTHWEST AND SOUTH CENTRAL NORTH DAKOTA...BUT HAS PRETTY MUCH
ENDED OVER THE NORTHWEST AND WEST CENTRAL FOR NOW. WILL UPDATE THE
WSW TO CANCEL THE ADVISORY FOR PORTIONS OF WEST CENTRAL AND
SOUTHWEST NORTH DAKOTA...MAINLY WATFORD CITY...TROTTERS...
KILLDEER...BEACH AND DICKINSON.
ADJUSTED EVENING POPS BASED ON LATEST RADAR IMAGERY AND THE 23 UTC
RAP. BRINGING HIGH CHANCE LOW QPF SNOWS THE FAR SOUTHWEST AND
CENTRAL THIS EVENING...THEN MOVING SLOWLY EAST AND TAPERING LATE
THIS EVENING AND OVERNIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 305 PM CST TUE DEC 31 2013
MAIN HIGHLIGHTS IN THE SHORT TERM PERIOD ARE THE WINTER WEATHER
ADVISORY SOUTHWEST AND WIND CHILL ADVISORY NORTH AND EAST CENTRAL.
ONLY SUBTLE CHANGES TO PREVIOUS FORECASTS AS THE MAIN IDEAS
MENTIONED ABOVE REMAIN NEARLY THE SAME.
LATEST WATER VAPOR IMAGERY/RADAR LOOP/SURFACE OBSERVATIONS
CONTINUE TO SUPPORT A COUPLE MINOR SHORTWAVES UPSTREAM IN ALBERTA
AND WESTERN SASKATCHEWAN INTERACTING WITH A QUASI-STATIONARY
FRONT IN EASTERN MONTANA AND INTO WESTERN SOUTH DAKOTA. AN INVERTED
SURFACE TROUGH IS FORECAST TO SHIFT ACROSS EASTERN MONTANA EARLY
TONIGHT AND INTO WESTERN NORTH DAKOTA BY 12Z WEDNESDAY...THEN
CONTINUE INTO CENTRAL NORTH DAKOTA BY AROUND 18Z WEDNESDAY. IN
DOING SO...EXPECT A WINDSHIFT TO THE NORTHWEST WHICH WILL
TEMPORARILY SQUASH THE OVERRUNNING PATTERN AND FORCE THE TIGHTEST
PORTION OF THE BAROCLINIC ZONE FARTHER SOUTHWEST. THUS WITH THE
SURFACE TROUGH APPROACHING OVERNIGHT IN COMBINATION WITH THE
AFOREMENTIONED SHORTWAVES AND WEAK FORCING...A HIGH POP/LOW QPF
EVENT WILL BE MAINTAINED IN THE GRIDDED FORECAST. EXPECT A GRADUAL
TRANSITION OF LIGHT SNOW FROM WEST TO EAST OVERNIGHT INTO WEDNESDAY
MORNING ALONG AND AHEAD OF THE SURFACE TROUGH. SNOWFALL AMOUNTS OF
ANOTHER HALF INCH OR SO POSSIBLE THROUGH THE OVERNIGHT PERIOD.
WILL ALLOW THE WINTER WEATHER ADVISORY TO CONTINUE THROUGH TUESDAY
EVENING AS SCHEDULED IN THE SOUTHWEST.
THE WIND CHILL ADVISORY WILL BE MAINTAINED THROUGH 17Z WEDNESDAY
FOR PORTIONS OF NORTH AND EAST CENTRAL NORTH DAKOTA WITH WIND
CHILL TEMPERATURES AS LOW AS 30 BELOW.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 305 PM CST TUE DEC 31 2013
FORECAST CONCERNS AGAIN WILL FOCUS ON THE ARCTIC INTRUSION FORECAST
THIS COMING WEEKEND INTO EARLY NEXT WEEK. WHILE MODEL DIFFERENCES
EXIST...THE MAIN SCENARIO THIS WEEK WILL BE A COLD WEDNESDAY
NIGHT...A WARM UP THURSDAY AND FRIDAY AHEAD OF A POTENTIALLY VIGOROUS
ARCTIC FRONT...AND THE ARRIVAL OF ARCTIC AIR LATE IN THE WEEKEND.
WEDNESDAY NIGHT WILL SEE AN ARCTIC HIGH OVER THE EASTERN DAKOTAS
WITH A WARM FRONT TROUGH IN THE LEE OF THE ROCKIES. A COLD NIGHT
MOST AREAS...WITH LOWS AROUND 15 TO 25 BELOW NORTH AND
CENTRAL...WITH ZERO TO 15 BELOW SOUTHWEST.
SOME MILD AIR ACROSS THE EASTERN PACIFIC WILL BE MOVE ACROSS THE
ROCKIES INTO THE NORTHERN PLAINS THURSDAY...THURSDAY NIGHT...AND
FRIDAY. ON THURSDAY HIGH TEMPERATURES WILL LIKELY BE AROUND ZERO
OVER EASTERN PORTIONS OF CENTRAL NORTH DAKOTA...BUT THE WARM FRONT
WILL NUDGE INTO THE WEST AND FAR WESTERN NORTH DAKOTA SHOULD SEE
TEMPERATURES RISING INTO THE 20S TO AROUND 30 ABOVE BY LATE
AFTERNOON/EVENING THURSDAY. RISING TEMPERATURES ARE ANTICIPATED
THURSDAY NIGHT...AND FRIDAY SHOULD SEE HIGHS IN THE 30S ACROSS ALL
OF WESTERN AND CENTRAL NORTH DAKOTA. ON FRIDAY THERE SHOULD BE A
CHANCE OF RAIN AND SNOW ACROSS THE SOUTHWEST AND PARTS OF THE SOUTH
CENTRAL WITH A CHANCE OF SNOW ELSEWHERE.
THE LEADING EDGE OF COLD ARCTIC AIR WILL ENTER THE NORTHWEST PORTION
OF THE STATE FRIDAY AFTERNOON. RAISED WINDS FROM THE ALLBLEND
GUIDANCE FRIDAY AND FRIDAY NIGHT. THIS FIRST BATCH OF COLD
AIR WILL BE MORE MODERATE...WITH THE MODELS SAVING THE COLDEST AIR
FOR SUNDAY AND MONDAY. LOWS SUNDAY NIGHT SHOULD BE IN THE 15 TO 25
BELOW RANGE...WITH HIGHS MONDAY 5 TO 15 BELOW...AND LOWS MONDAY
NIGHT AGAIN IN THE 15 TO 25 BELOW ZERO RANGE. WIND CHILLS ARE
FORECAST TO REACH DANGEROUS ADVISORY AND WARNING CRITERIA SATURDAY
NIGHT THROUGH TUESDAY - WITH THE LOWEST READINGS EXPECTED SUNDAY
NIGHT THROUGH MONDAY MORNING LIKELY IN THE WARNING CATEGORY (-40 AND
BELOW) ACROSS THE REGION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 934 PM CST TUE DEC 31 2013
MAINLY VFR CEILINGS AND VISIBILITIES ARE EXPECTED THROUGH THE
FORECAST PERIOD. AN IMPULSE WILL BRING LOWER CEILINGS AND
VISIBILITIES TO SOUTHWEST NORTH DAKOTA LATE TONIGHT THROUGH EARLY
MORNING WEDNESDAY TO MAINLY SOUTHWEST NORTH DAKOTA INCLUDING KDIK.
WINDS WILL REMAIN LIGHT AND VARIABLE THROUGH THE FORECAST
PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 11 AM CST WEDNESDAY FOR NDZ002>005-
011>013-022-023-025-036-037-047-048-050-051.
&&
$$
UPDATE...TWH
SHORT TERM...KS
LONG TERM...JV
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1140 PM CST SUN DEC 29 2013
.UPDATE...
ISSUED AT 1137 PM CST SUN DEC 29 2013
ADJUSTED TEMPERATURES ACROSS THE WESTERN FA TO GENERALLY STEADY
VALUES OVERNIGHT. ALSO ADJUSTED CLOUD TRENDS SLIGHTLY AND AGAIN
DELAYED POPS SLIGHTLY ACROSS THE WEST.
UPDATE ISSUED AT 934 PM CST SUN DEC 29 2013
WITH SURFACE RIDGE AXIS ACROSS WESTERN MN RESULTING IN LIGHT WINDS AND
ADVANCING CLOUDS FROM THE WEST ALLOWING TEMPERATURES TO MODERATE
HAVE CANCELLED THE WIND ADVISORY ACROSS THE FORECAST AREA. MADE
SOME MINOR TEMPERATURE ADJUSTMENTS ACROSS THE WEST OTHERWISE
MINIMUMS SEEM REASONABLE. BASED ON CURRENT RADAR TRENDS AND
MESOSCALE MODEL GUIDANCE HAVE DELAYED MOVING -SN INTO THE W-SW FA
UNTIL AFTER MIDNIGHT.
UPDATE ISSUED AT 628 PM CST SUN DEC 29 2013
NO CHANGES PLANNED THIS UPDATE PERIOD. APPARENT TEMPERATURES NOT
VERY IMPRESSIVE AT THIS POINT WITH LIGHT WINDS BUT WILL MONITOR.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 248 PM CST SUN DEC 29 2013
FORECAST CHALLENGE TONIGHT WILL BE EASTWARD EXTEND OF CLOUDS OVER
CENTRAL NORTH DAKOTA AND THEIR IMPACT ON TEMPS AND WIND CHILL
HEADLINES. OVERALL CLOUDS ADVECTING EAST QUICKER THAN INITIALLY
THOUGHT...AND MAY MAKE DEVILS LAKE BY 00Z. MODELS HAVE STRUGGLED
TO WITH PICKING UP ON THE MOISTURE...MAINLY HIGHLIGHTING THE
HIGHER CLOUDS OVER MINOT AND WEST. USING MAINLY SATELLITE TRENDS
FOR THE NEAR TERM AND MORE OF A ECMWF/NAM BLEND FOR THE EARLY PART
OF THE WEEK.
TONIGHT...CLOUDS WILL SLOWLY SPREAD INTO EASTERN ND AND APPROACH
THE RRV BY MIDNIGHT. A RATHER BULLISH CROSS SECTION FROM RUGBY TO
GRAND FORKS BRINGS CLOUDS INTO GFK BY 03Z..WHICH I THINK IS A BIT
TOO FAST. AS STATED PREVIOUSLY...MODELS ARE STRUGGLING WITH
ESPECIALLY THE LOWER CLOUDS THAT WERE PRESENT EARLY THIS MORNING.
THE RAP AVIATION FLIGHT RULES PRODUCT BRINGS THE LOW CLOUDS INTO
THE VALLEY AROUND THE 06Z/07Z TIME FRAME...BUT MID CLOUD SHOULD
ARRIVE PRIOR TO THAT. SO THE QUESTION BECOMES HOW FAST WILL TEMPS
DROP OFF AS THE SUN ANGLE DECREASES IN THE LATE AFTN...AND THEIR
IS ENOUGH WIND TO KEEP US IN ADVISORY CRITERIA THROUGH CURRENTLY
ADVERTISED TIMES. WILL NOT MAKE ANY CHANGES TO HEADLINES AT THIS
POINT BUT MAY SEE ADVISORY CANCELLED ACROSS EASTERN ND WELL AHEAD
OF SCHEDULE IF CLOUDS CAN LEVEL OFF THE TEMP CURVE QUICK ENOUGH.
OTHER ISSUE IS THAT WINDS ARE RATHER LIGHT...BUT ONLY TAKES 2 TO 3
KNOTS IN THE COLDEST AIR TO GET APPARENT TEMPS IN ADVISORY
CRITERIA. AGAIN...WILL KEEP HEADLINES IN PLACE AS IT IS GOING TO
BE DARN COLD TONIGHT WITHIN AND EAST OF THE VALLEY.
TOMORROW AND TOMORROW NIGHT...A WEAK WAVE WILL MOVE ACROSS CENTRAL
DAKOTAS AND SHOULD RESULT IN A BAND OF VERY DRY FLUFF ACROSS THE
CENTRAL PART OF THE STATE. THIS MAY CLIP THE SHEYENNE
VALLEY...WITH THE BEST CHANCES FOR UP TO TWO INCHES OF FLUFF BEING
FROM EDDY DOWN TO RANSOM/SARGENT COUNTIES. EXPECT SNOWFALL TO BE
INTO MAINLY WEST CENTRAL MN AFTER NOON...AND OUT OF THE REGION BY
EARLY MONDAY EVENING.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 248 PM CST SUN DEC 29 2013
TUESDAY AND WEDNESDAY...A SERIES OF WAVES EMBEDDED IN THE NW FLOW
PATTERN WILL BRING MORE CHANCES OF LIGHT SNOW MAINLY IN THE FAR
WEST ON TUE AND WED. THE WED SYSTEM...ALTHOUGH WEAKER AND
DRIER...SHOULD GIVE OUR CWA A LITTLE BETTER CHANCE AS THE UPPER
PATTERN SHIFTS EAST AND THE TRACK OF THE WAVES MOVES FROM THE
CENTRAL TO THE EASTERN DAKOTAS. EACH WAVE WILL GENERALLY BE MORE
DRY FLUFF THAT MAY ACCUMULATE AN INCH OR TWO DUE TO HIGH SNOWFALL
RATIOS WITH VERY LITTLE LIQUID EQUIVALENT.
WEDNESDAY NIGHT-SUNDAY...MODELS ARE IN GOOD AGREEMENT. THE PERIOD
STARTS WITH THE REGION IN NORTHWEST FLOW ALOFT...ALONG WITH HIGH
PRESSURE AND VERY COLD TEMPERATURES. THE UPPER PATTERN THEN
DEAMPLIFIES...ALLOWING ZONAL FLOW BY THE WEEKEND. THIS WILL LEAD TO
MUCH WARMER TEMPERATURES ON FRIDAY. A SYSTEM WILL MOVE THROUGH
SOUTHERN CANADA...SENDING A COLD FRONT THROUGH THE FA LATE FRIDAY OR
EARLY SATURDAY. LIGHT SNOW AND WINDY CONDITIONS POSSIBLE WITH THIS
FEATURE...ALTHOUGH DETAILS ARE FUZZY. TEMPERATURES WILL BE A BIT
COOLER FOR THE WEEKEND (COMPARED TO FRIDAY). MODELS SHOW A MUCH
STRONGER COLD FRONT POSSIBLE FOR LATER SUNDAY OR EARLY MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1137 PM CST SUN DEC 29 2013
MAINTAINED VFR CIGS ACROSS THE FA THROUGH THE FORECAST PERIOD.
LIGHT SNOW WILL SPREAD INTO THE SW THIRD OF THE FA BY SUNRISE.
COULD SEE SOME MVFR VSBY CLIP THE FAR TAF SITE DURING THE AM.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...VOELKER
SHORT TERM...SPEICHER
LONG TERM...TG/SPEICHER
AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1246 PM EST MON DEC 30 2013
.SYNOPSIS...
WEAK HIGH PRESSURE WILL BUILD ACROSS THE AREA TODAY AND TUESDAY AS
A COLDER AIRMASS SETTLES INTO THE REGION. A DEVELOPING LOW
PRESSURE SYSTEM WILL MOVE ACROSS THE REGION THROUGH MID WEEK...BRINGING
A BETTER CHANCE OF PRECIPITATION WEDNESDAY NIGHT INTO THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HAVE UPDATED FORECAST TO INCLUDE SCATTERED SNOW SHOWERS WHICH HAVE
DEVELOPED IN A COLD AND SOMEWHAT MOIST NORTHWEST FLOW. RAP MODEL
SOUNDINGS SHOW INSTABILITY AND MOISTURE UP TO ABOUT 4000 FT
AGL...WHICH IS APPARENTLY DEEP ENOUGH TO ALLOW SNOW SHOWER
FORMATION. EXPECT A DUSTING OF ACCUMULATION. LOW LEVEL FLOW WILL
QUICKLY BACK THROUGH LATE MORNING AND AS IT DOES...EXPECT
REMAINING PCPN CHANCES TO TAPER OFF. LOW LEVEL CAA WILL PERSIST
THROUGH THE MORNING BEFORE TAPERING OFF THIS AFTERNOON. EXPECT
HIGHS GENERALLY RANGING FROM THE MID 20S NORTHWEST TO LOWER 30S
SOUTHEAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
A SERIES OF WEAK UPPER LEVEL DISTURBANCES WILL PUSH EAST ACROSS THE
GREAT LAKES TONIGHT INTO WEDNESDAY. THE BEST FORCING WITH THESE
WILL REMAIN OFF TO OUR NORTH...BUT OUR FAR NORTHERN COUNTIES WILL
REMAIN ON THE SOUTHERN FRINGE. WILL THEREFORE INCLUDE SOME 20
POPS FOR LIGHT SNOW ACROSS OUR FAR NORTH LATE TONIGHT AND AGAIN
LATER TUESDAY NIGHT INTO WEDNESDAY. A BETTER CHANCE FOR
PRECIPITATION WILL BEGIN TO DEVELOP THROUGH WEDNESDAY AFTERNOON
ACROSS THE NORTH AS A STRONGER SHORT WAVE APPROACHES THE AREA FROM
THE WEST. TEMPERATURES WILL SLOWLY MODERATE THROUGH MID WEEK.
HIGHS ON TUESDAY WILL BE IN THE UPPER 20S TO MID 30S WITH LOWER 30S
TO LOWER 40S EXPECTED ON WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
THE MODELS PHASE SRN AND NRN STREAM ENERGY ACROSS THE ERN U.S.
WEDNESDAY NIGHT INTO THURSDAY. AS THIS OCCURS PCPN OVERSPREADS THE
THE FA THURSDAY NIGHT. THE ECMWF REMAINS THE MOST WOUND UP AND
SLOW WITH ITS SFC LOW. WENT WITH A MORE BLENDED SOLUTION. THIS
KEEPS THE N ALL SNOW AND A RAIN/SNOW MIX IN THE S BEFORE CHANGING
OVER TO ALL SNOW.
AS THE LOW PULLS E THURSDAY NIGHT...A STRONG NLY FLOW WILL BRING A
BLAST OF ARCTIC AIR INTO THE REGION. COULD SEE LINGERING SNOW
SHOWERS INTO FRIDAY. HIGH PRESSURE THEN BUILDS IN FRIDAY NIGHT.
BY SUNDAY WAA ISENTROPIC LIFT AHEAD OF A FNT LIFTING OUT OF THE
MIDDLE OF THE COUNTRY WILL SPREAD MORE PCPN INTO THE FA. THICKNESSES
ARE COLD ENUF FOR THE PCPN TO BEGIN AS SNOW...BUT THEN CHANGE TO
RAIN DURING THE DAY ON SUNDAY.
THURSDAY COULD SEE HIGHS DURING THE LATE MORNING HOURS BEFORE
TEMPERATURES FALL AS THE LOW PRESSURE HEADS E. AFTER LOWS FRIDAY
MORNING IN THE SINGLE DIGITS IN THE NW TO THE TEENS ACROSS THE
S...HIGHS WILL ONLY MAKE THE 20S FRIDAY AFTN. SATURDAY SHOULD SEE
A LITTLE WARMUP WITH EVERYONE MAKING THE 30S. SUNDAY COULD SEE SRN
LOCATIONS REACHING THE 40S AGAIN.
&&
.AVIATION /18Z MONDAY THROUGH FRIDAY/...
MVFR CEILINGS AND SNOW FLURRIES WILL PERSIST FOR A FEW MORE HOURS
UNTIL A WEAK RIDGE BUILDS IN THIS EVENING. VFR IS EXPECTED
TONIGHT. MVFR CEILINGS ASSOCIATED WITH A WEAK TROUGH ARE FORECAST
FOR TUESDAY. VFR SHOULD RETURN TO CVG AFTER 18Z TUESDAY AS ANOTHER
WEAK RIDGE MOVES IN. WINDS SHIFTING TO WEST WILL INCREASE WITH A
TIGHTENING PRESSURE GRADIENT ON TUESDAY...WITH GUSTS OVER 20 KNOTS
LIKELY.
OUTLOOK...MVFR CEILINGS POSSIBLE WEDNESDAY NIGHT INTO THURSDAY
EVENING. MVFR TO IFR VISIBILITIES POSSIBLE THURSDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...JGL
NEAR TERM...CONIGLIO/JGL
SHORT TERM...JGL
LONG TERM...SITES
AVIATION...CONIGLIO
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
956 AM EST MON DEC 30 2013
.SYNOPSIS...
WEAK HIGH PRESSURE WILL BUILD ACROSS THE AREA TODAY AND TUESDAY AS
A COLDER AIRMASS SETTLES INTO THE REGION. A DEVELOPING LOW
PRESSURE SYSTEM WILL MOVE ACROSS THE REGION THROUGH MID WEEK...BRINGING
A BETTER CHANCE OF PRECIPITATION WEDNESDAY NIGHT INTO THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HAVE UPDATED FORECAST TO INCLUDE SCATTERED SNOW SHOWERS WHICH HAVE
DEVELOPED IN A COLD AND SOMEWHAT MOIST NORTHWEST FLOW. RAP MODEL
SOUNDINGS SHOW INSTABILITY AND MOISTURE UP TO ABOUT 4000 FT
AGL...WHICH IS APPARENTLY DEEP ENOUGH TO ALLOW SNOW SHOWER
FORMATION. EXPECT A DUSTING OF ACCUMULATION. LOW LEVEL FLOW WILL
QUICKLY BACK THROUGH LATE MORNING AND AS IT DOES...EXPECT
REMAINING PCPN CHANCES TO TAPER OFF. LOW LEVEL CAA WILL PERSIST
THROUGH THE MORNING BEFORE TAPERING OFF THIS AFTERNOON. EXPECT
HIGHS GENERALLY RANGING FROM THE MID 20S NORTHWEST TO LOWER 30S
SOUTHEAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
A SERIES OF WEAK UPPER LEVEL DISTURBANCES WILL PUSH EAST ACROSS THE
GREAT LAKES TONIGHT INTO WEDNESDAY. THE BEST FORCING WITH THESE
WILL REMAIN OFF TO OUR NORTH...BUT OUR FAR NORTHERN COUNTIES WILL
REMAIN ON THE SOUTHERN FRINGE. WILL THEREFORE INCLUDE SOME 20
POPS FOR LIGHT SNOW ACROSS OUR FAR NORTH LATE TONIGHT AND AGAIN
LATER TUESDAY NIGHT INTO WEDNESDAY. A BETTER CHANCE FOR
PRECIPITATION WILL BEGIN TO DEVELOP THROUGH WEDNESDAY AFTERNOON
ACROSS THE NORTH AS A STRONGER SHORT WAVE APPROACHES THE AREA FROM
THE WEST. TEMPERATURES WILL SLOWLY MODERATE THROUGH MID WEEK.
HIGHS ON TUESDAY WILL BE IN THE UPPER 20S TO MID 30S WITH LOWER 30S
TO LOWER 40S EXPECTED ON WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
THE MODELS PHASE SRN AND NRN STREAM ENERGY ACROSS THE ERN U.S.
WEDNESDAY NIGHT INTO THURSDAY. AS THIS OCCURS PCPN OVERSPREADS THE
THE FA THURSDAY NIGHT. THE ECMWF REMAINS THE MOST WOUND UP AND
SLOW WITH ITS SFC LOW. WENT WITH A MORE BLENDED SOLUTION. THIS
KEEPS THE N ALL SNOW AND A RAIN/SNOW MIX IN THE S BEFORE CHANGING
OVER TO ALL SNOW.
AS THE LOW PULLS E THURSDAY NIGHT...A STRONG NLY FLOW WILL BRING A
BLAST OF ARCTIC AIR INTO THE REGION. COULD SEE LINGERING SNOW
SHOWERS INTO FRIDAY. HIGH PRESSURE THEN BUILDS IN FRIDAY NIGHT.
BY SUNDAY WAA ISENTROPIC LIFT AHEAD OF A FNT LIFTING OUT OF THE
MIDDLE OF THE COUNTRY WILL SPREAD MORE PCPN INTO THE FA. THICKNESSES
ARE COLD ENUF FOR THE PCPN TO BEGIN AS SNOW...BUT THEN CHANGE TO
RAIN DURING THE DAY ON SUNDAY.
THURSDAY COULD SEE HIGHS DURING THE LATE MORNING HOURS BEFORE
TEMPERATURES FALL AS THE LOW PRESSURE HEADS E. AFTER LOWS FRIDAY
MORNING IN THE SINGLE DIGITS IN THE NW TO THE TEENS ACROSS THE
S...HIGHS WILL ONLY MAKE THE 20S FRIDAY AFTN. SATURDAY SHOULD SEE
A LITTLE WARMUP WITH EVERYONE MAKING THE 30S. SUNDAY COULD SEE SRN
LOCATIONS REACHING THE 40S AGAIN.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
SNOW FLURRIES WILL SPREAD ACROSS THE AREA THIS MORNING UNDER MOIST
NORTHWESTERLY FLOW OFF THE GREAT LAKES WITH MVFR CIGS EXPECTED.
BY THE LATE MORNING...LOW LEVEL FLOW WILL BEGIN TO BACK...WHICH
SHOULD END THE CHANCE FOR FLURRIES. CIGS ARE EXPECTED TO GRADUALLY
RAISE TO VFR DURING THE DAY WITH SOME BREAKS DEVELOPING IN THE
CLOUD COVER AS WELL. WEAK HIGH PRESSURE WILL PASS ACROSS THE
REGION BY THE EARLY EVENING WHICH WILL ALLOW WINDS TO BECOME
LIGHT. OVERNIGHT TONIGHT...A DISTURBANCE PASSING TO THE NORTH OF
THE AREA WILL BRING AN INCREASE IN WESTERLY WINDS UP TO 10 KT AS
WELL AS ADDITIONAL VFR CLOUD COVER. LIGHT SNOW ASSOCIATED WITH
THIS DISTURBANCE IS EXPECTED TO STAY NORTH OF OUR TERMINALS
TONIGHT.
OUTLOOK...MVFR CEILINGS POSSIBLE WEDNESDAY NIGHT INTO THURSDAY
EVENING. MVFR TO IFR VISIBILITIES POSSIBLE THURSDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...JGL
NEAR TERM...CONIGLIO/JGL
SHORT TERM...JGL
LONG TERM...SITES
AVIATION...LATTO
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
820 PM MST TUE DEC 31 2013
.UPDATE...
ISSUED AT 814 PM MST TUE DEC 31 2013
03Z SURFACE ANALYSIS HAD FRONTAL BOUNDARY FROM CENTRAL MT INTO
SOUTHEAST WY. RADAR SHOWING STRIPE OF -SN FROM NORTHEAST WY INTO
SOUTH CENTRAL SD. DUAL-POL SIGNATURES SUGGEST MIXED PRECIPITATION
IS LARGELY OVER GIVEN LIFT PAST SEVERAL HOURS ERASING ABOVE 0C
LAYER ON 00Z KUNR SOUNDING. WILL REMOVE MIXED PRECIPITATION FROM
FORECAST. 00Z RAP/NAM SHOW INITIAL WAVE WITH BAND OF -SN HEADING
SOUTH THIS EVENING AND SLOWLY WANING. NEXT UPSTREAM WAVE OVER MT
WILL BRING ANOTHER ROUND OF -SN TO SOUTHWEST PORTIONS OF CWA LATER
TONIGHT INTO WEDNESDAY MORNING. HAVE ADJUSTED POPS/WEATHER TO
MATCH LATEST THINKING.
WILL LEAVE HEADLINES IN PLACE GIVEN LIGHT SNOW ON TOP OF SLUSHY
ROADS FROM PREVIOUS MIXED PRECIPITATION.
UPDATE ISSUED AT 530 PM MST TUE DEC 31 2013
DUAL-POL RADAR DATA SHOWING SOME SLEET FROM STURGIS TOWARD
PHILIP...SUPPORTED BY 00Z KUNR SOUNDING...SO WILL ADD TO UPDATED
FORECAST. 00Z KUNR SOUNDING AND LATEST RAP GUIDANCE SUPPORTS
CHANGEOVER TO ALL SNOW BY MID-EVENING. UPDATED FORECAST WILL ALSO
RAISE POPS TO BETTER MATCH LATEST RADAR LOOPS.
UPDATE ISSUED AT 353 PM MST TUE DEC 31 2013
CALL TO AREA SPOTTERS SHOWED A BAND OF SLEET/FREEZING RAIN FROM
SOUTHEAST MT INTO WESTERN MEADE COUNTY...INCLUDING THE I-90
CORRIDOR FROM STURGIS TO SPEARFISH TO MOORCROFT. 21Z RAP SHOWED
NARROW BAND OF MIXED PRECIPITATION POTENTIAL FOR THESE AREAS
THROUGH ABOUT 04Z...WHEN EVERYTHING SHOULD SHIFT TO -SN. HAVE
INTRODUCED THESE ELEMENTS TO FORECAST AND ISSUED HEADLINES FOR THE
APPROPRIATE AREAS.
&&
.SHORT TERM...THIS EVENING THROUGH WEDNESDAY NIGHT
ISSUED AT 208 PM MST TUE DEC 31 2013
UPPER LEVEL ANALYSIS SHOWS NORTHWEST FLOW OVER THE
NORTHERN PLAINS. SURFACE MAP HAS AN ARCTIC BOUNDARY STRETCHING FROM
MONTANA THROUGH THE CWA INTO NEBRASKA. WARMER TEMPS TO THE SOUTH OF
THE BOUNDARY ARE IN THE 30S...WITH TEMPS TO THE NORTH IN THE SINGLE
DIGITS. LOW STRATUS COVERS MUCH OF THE REGION...WITH RADAR
DISPLAYING SOME LIGHT SNOW SHOWERS. WINDS ARE LIGHT AND VARIABLE.
AS THE ARCTIC BOUNDARY SPREADS SOUTH TONIGHT AND A SHORTWAVE
APPROACHES FROM THE WEST...LIGHT SNOW WILL TRANSITION SOUTH WITH THE
BEST FRONTOGENESIS. GENERALLY A COUPLE ADDITIONAL INCHES OR LESS OF
SNOW IS EXPECTED TONIGHT...WITH THE GREATER AMOUNTS OVER PARTS OF
NORTHEAST WYOMING AND THE NORTHERN BLACK HILLS. LOWS WILL RANGE FROM
AROUND 5 BELOW ZERO ACROSS CENTRAL SD TO ABOUT 20 ABOVE ZERO FARTHER
WEST.
SURFACE HIGH PRESSURE WILL SLIDE ACROSS ND ON NEW YEAR`S DAY...AND THE
PRESSURE GRADIENT WILL TIGHTEN A LITTLE...CAUSING BREEZY NORTHWEST
WINDS ACROSS NORTHWEST SD. LIGHT SNOW WILL CONTINUE THROUGH MUCH OF
THE DAY...WITH MINIMAL ACCUMULATIONS MOST PLACES. THE FROUDE NUMBER
AROUND 1.5 INDICATES THE POSSIBILITY FOR UPSLOPE-ENHANCED SNOW OVER
THE NORTHERN HILLS...ACCUMULATING ANOTHER INCH OR TWO THERE. HIGHS
WILL RANGE FROM THE TEENS ACROSS CENTRAL SD TO THE LOWER 30S IN
SOUTHWEST SD AND NORTHEAST WY.
SNOW WILL DIMINISH AND SKIES WILL BEGIN TO CLEAR WEDNESDAY NIGHT.
LOWS WILL BE AROUND 10 BELOW TO 15 ABOVE ZERO.
&&
.LONG TERM...THURSDAY THROUGH TUESDAY
ISSUED AT 208 PM MST TUE DEC 31 2013
POWERFUL NORTHERN STREAM WILL CONTINUE TO DOMINATE THE
WEATHER IN THE PERIOD. MEAN CENTRAL CANADIAN POLAR VORTEX
WILL DRIVE ANOTHER SURGE OF ARCTIC AIR INTO THE REGION BY
SUNDAY...AS A LONG WAVE TROUGH ADVECTS ACROSS THE NW CONUS AND
PHASES WITH A PORTION OF THE POLAR LOW. PROGRESSIVE FLOW OVER THE
WESTERN ATLANTIC WILL SUPPORT ONLY A BRIEF STAY OF ARCTIC AIR
LOCALLY AS SEMI-ZONAL FLOW DEVELOPS ONCE AGAIN EARLY NEXT WEEK. MEAN
MODEL SOLUTIONS ARE SUGGESTING A POTENTIAL PATTERN CHANGE BY THE
MIDDLE OF NEXT WEEK WITH BREAKDOWN OF THE EASTERN PAC UPPER
RIDGE...ALLOWING A RETURN TO PROGRESSIVE FLOW OVER MUCH OF
NOAM...WITH THE POTENTIAL FOR A WARMER PATTERN AFTERWARD.
THUR-FRI...DEEP LAYER RIDGING AHEAD OF THE ADVECTING UPPER TROUGH
WILL SUPPORT STAUNCH WAA WITH WESTERLY FLOW SPREADING OVER THE
REGION. HAVE ADJUSTED TEMPS BOTH DAYS...WITH MILD CONDITIONS
EXPECTED OVER NE WY AND BH THUR...ALL PLACES FRIDAY AS FLOW
INCREASES AND MIXING SPREADS ACROSS THE SD PLAINS. 40S WILL BE
COMMON FRI...WITH 50S EXPECTED IN THE LEE OF THE BLACK
HILLS...INCLUDING RAPID CITY. THE RIDGE WILL SHIFT EAST FRIDAY
AFTERNOON...WITH A STRONG UPPER IMPULSE EXPECTED INTO THE
REGION...BRINGING INCREASING CHANCES FOR PRECIP...RAIN POSSIBLY AT
FIRST THEN TRANSITIONING TO SNOW FRIDAY EVENING. CONTINUED POP
MENTION IN THE PERIOD...OPTING FOR A MORNING MENTION OVER WY. ARCTIC
FRONT AND ASSOCIATED IMPULSE WILL ARRIVE SUN...WITH A CONTINUED POP
MENTION THEN. ALTHOUGH MOISTURE WILL BE SIGNIFICANTLY LACKING WITH
THIS SYSTEM...BEST CHANCES FOR ANY SNOW ACCUMS WILL BE OVER NE WY
AND THE NORTHERN BH. ARCTIC AIR WILL SURGE SOUTH ACROSS THE REGION
SUNDAY INTO MONDAY WITH VERY COLD TEMPS EXPECTED. MADE A SLIGHT DOWN
ADJUSTMENT TO TEMPS GIVEN BETTER MODEL AGREEMENT...ALTHOUGH CONCERNS
LINGER ON THE DEGREE OF CAA. WAA LOOKS TO ENSUE AS EARLY AS MON
AFTERNOON PER THE ECMWF...WITH A SLOW WARMUP ON TRACK THROUGH THE
MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 814 PM MST TUE DEC 31 2013
IFR CIGS/VSBYS EXPECTED THROUGH WEDNESDAY MORNING WITH -SN WITH
LOCAL LIFR CONDITIONS OVER THE BLACK HILLS. MVFR CIGS EXPECTED
OUTSIDE OF -SN. CONDITIONS WILL SLOWLY IMPROVE WEDNESDAY
AFTERNOON/EVENING.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL 5 AM MST WEDNESDAY FOR SDZ012-024-
025-072.
WY...WINTER WEATHER ADVISORY UNTIL 5 AM MST WEDNESDAY FOR WYZ056-057-
071.
&&
$$
UPDATE...HELGESON
SHORT TERM...POJORLIE
LONG TERM...JC
AVIATION...HELGESON
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
914 PM CST TUE DEC 31 2013
.UPDATE...
ISSUED AT 842 PM CST TUE DEC 31 2013
WHILE THE OVERALL THINKING OF THE FORECAST IN TERMS OF
DYNAMICS/FORCING REMAINS SIMILAR TO WHAT IS DISCUSSED
BELOW...HAVE MADE SOME CHANGES IN RESPONSE TO LATEST MODEL RUNS
AND CURRENT WEATHER. FIRST OF ALL...DID GO AHEAD AN ISSUE A WIND
CHILL ADVISORY FOR PORTIONS OF THE HIGHWAY 14 CORRIDOR/MOST OF
SOUTHWEST MINNESOTA AND INTO THE IOWA GREAT LAKES AREA FOR THE
REMAINDER OF TONIGHT INTO WEDNESDAY MORNING. THE REASONING BEHIND
THIS IS THAT TEMPERATURES HAVE BEEN DROPPING QUICKER THAN THOUGHT
OVER THAT AREA...AND WINDS HAVE REMAINED A LITTLE STRONGER THAN
FORECASTED. STILL ANTICIPATE THAT WINDS WILL TAPER DOWN LATER IN
THE NIGHT AS THE GRADIENT RELAXES A BIT...BUT EVEN SO...WITH
TEMPERATURES AROUND 10 BELOW ZERO OVER THAT AREA...WIND CHILL
VALUES OF 20 TO 25 BELOW ZERO WILL BE REALIZED OVERNIGHT.
OUR ATTENTION THEN TURNS TO THE SNOW POTENTIAL ACROSS MOST OF THE
AREA LATER TONIGHT INTO EARLY WEDNESDAY MORNING. STILL HAVING RUN
TO RUN DIFFERENCES IN THE MODELS...WITH THE 00Z NAM NOW TRENDING
BACK TO THE SOUTH. THIS ALIGNS IT WELL WITH MOST OTHER MODELS
PUTTING THE BRUNT OF THE PRECIPITATION THROUGH THE MISSOURI RIVER
CORRIDOR...OUTSIDE OF THE 12Z GEM WHICH TAKES IT FARTHER TO THE
NORTH. WHAT IS A LITTLE MORE DISTURBING IS THAT LATEST MODELS
CONTINUE TO COME IN A LITTLE WETTER. IN LIGHT OF THAT...UPPED QPF
AMOUNTS ACROSS THAT AREA...YIELDING SNOWFALL TOTALS CLOSER TO 3
INCHES. CANNOT RULE OUT LOCALIZED HIGHER AMOUNTS...PUSHING INTO
ADVISORY CRITERIA...BUT THINK THAT MOST OF THE EFFECTED AREA WILL
REMAIN JUST BELOW THAT. UPDATES ARE OUT.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 339 PM CST TUE DEC 31 2013
SNOW ASSOCIATED WITH TODAYS WAVE IS EXITING THE AREA...WITH JUST
SOME ISOLATED TO SCATTERED FLURRIES LINGERING. ANOTHER WAVE WILL RIDE
SOUTHEAST ALONG THE THERMAL GRADIENT TONIGHT. MODELS HAVE HAD GREAT
DIFFICULTY PINPOINTING WHERE THE BEST SNOW POTENTIAL WILL BE WITH
THIS WAVE...AND HOW MUCH QPF WILL FALL. THUS NEEDLESS TO SAY A LOW
CONFIDENCE FORECAST. BEST LARGE SCALE FORCING FROM THE WAVE SEEMS TO
GO TO OUR SOUTH. HOWEVER THE MID LEVEL FRONTAL BOUNDARY SHOULD BE
FURTHER NORTH...IN THE VICINITY OF THE MISSOURI RIVER VALLEY. LATEST
MODELS ARE TRENDING THE AREA OF SNOW FURTHER NORTH...CLOSER TO THE
REGION WHERE ISENTROPIC LIFT OVER THE MID LEVEL FRONT INTERACTS WITH
SOME OF THE LARGE SCALE FORCING. MODELS ALSO SHOWING SOME WEAK
INSTABILITY ABOVE THE FRONT...SUGGESTING WE COULD SEE SOME ENHANCED
BANDING. THE THERMAL PROFILE DOES FEATURE A DECENT SIZED AREA IN THE
DENDRITIC SNOW GROWTH ZONE...SUGGESTING RATIOS COULD END UP AROUND
15 TO 1. A CONSENSUS OF MODEL QPF VALUES SUGGEST 1 TO 2 INCHES IN
THE SNOW BAND...WITH ISOLATED AMOUNTS UP TO 3 INCHES IF RATIOS END
UP A BIT HIGHER. HOWEVER THE RUC...HRRR AND 18Z NAM ARE ALL MUCH
MORE AGGRESSIVE WITH QPF VALUES. THESE THREE WOULD SUGGEST A BAND OF
3 TO 5 INCHES. GIVEN THE LARGE SCALE FORCING...POTENTIAL BANDING AND
MODELS TRENDING UPWARD IN QPF...THIS CAN NOT BE COMPLETELY RULED
OUT. HOWEVER DO NOT WANT TO JUMP ON THIS AT THIS POINT GIVEN THE
REST OF THE GUIDANCE SUGGESTING LOWER AND THE MODEL INCONSISTENCY
FROM RUN TO RUN. THUS...TRENDED AMOUNTS UP...BUT ONLY TOWARDS MODEL
CONSENSUS...WHICH AT THIS TIME STILL SEEMS LIKE THE MORE LIKELY
SOLUTION.
THE NEXT QUESTION IS EXACTLY WHERE THIS BAND SETS UP. RIGHT
NOW ALMOST ALL GUIDANCE SUGGESTS THE MISSOURI RIVER VALLEY IS THE
MOST LIKELY LOCATION...WITH DECREASING AMOUNTS AS YOU GET TOWARDS
INTERSTATE 90. HOWEVER THE GEM AND HRRR ARE FURTHER NORTH...PUTTING
THE HIGHER AMOUNTS CLOSER TO OR JUST SOUTH OF INTERSTATE 90. FOR
THIS FORECAST PACKAGE WILL GO WITH THE MORE LIKELY SOLUTION ALONG
THE MISSOURI RIVER...BUT GIVEN THE RECENT NORTHWARD TRENDS CAN NOT
COMPLETELY RULE OUT THE HRRR AND GEM SOLUTION. SO FOR NOW...WILL
STICK WITH THE 1 TO 3 INCHES ALONG THE MISSOURI RIVER...DECREASING
TO AROUND AN INCH IN SIOUX FALLS AND LESS TO THE NORTH...BUT AS
MENTIONED ABOVE...EVENING SHIFT WILL NEED TO MONITOR TRENDS AND SEE
IF ADJUSTMENTS ARE NEEDED. EXPECT SNOW TO START AROUND 10 PM IN OUR
WEST...APPROACH SIOUX FALLS AND SIOUX CITY CLOSER TO MIDNIGHT...AND
SPENCER TO STORM LAKE AROUND 2 AM.
IT WILL BE A COLD ONE TONIGHT AS WELL WITH LOWS IN THE SINGLE DIGITS
BELOW ZERO NORTH OF INTERSTATE 90 AND SINGLE DIGITS ABOVE TO THE
SOUTH. KEPT THE TREND OF STAYING ON THE WARMER SIDE OF GUIDANCE
THOUGH...GIVEN THE CLOUD COVER AND AT LEAST A WEAKLY MIXED BOUNDARY
LAYER. WIND CHILLS WILL BE AROUND THE 20 BELOW ZERO ADVISORY CRITERIA
IN OUR NORTH. HOWEVER DECIDED TO HOLD OFF ON ONE AT THIS TIME...AS
WINDS SHOULD DROP OFF AFTER SUNSET AND GENERALLY BE UNDER 10
MPH...AND IF WINDS STAY UP MORE...TEMPERATURES WILL PROBABLY STAY A
BIT WARMER THAN FORECAST. THUS FEEL LIKE WIND CHILLS WILL HOVER A
FEW DEGREES EITHER SIDE OF 20 BELOW...AND GIVEN OUR COLD WINTER THUS
FAR...WILL NOT ISSUE ANOTHER ADVISORY AT THIS TIME. SNOW SHOULD EXIT
THE AREA FROM NORTHWEST TO SOUTHEAST ON WEDNESDAY MORNING...GIVING
WAY TO A MOSTLY CLOUDY DAY WITH JUST SOME SCATTERED FLURRIES. HIGHS
WILL WILL ONLY BE IN THE SINGLE DIGITS ABOVE AND BELOW ZERO WITH
WIND CHILLS LIKELY STAYING BELOW ZERO THROUGH THE DAY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 339 PM CST TUE DEC 31 2013
CONTINUED COLD WEATHER PATTERN LOCKED IN PLACE FOR THE MAJORITY OF
THE MID AND LONG RANGE FORECAST. PREDOMINATE NORTHWEST UPPER LEVEL
FLOW WILL USHER IN SEVERAL WAVES THROUGH THE PERIOD WHICH WILL
PROVIDE REINFORCING SHOTS OF ARCTIC AIR. THE FIRST BLAST OF COLD AIR
CONTINUES TO SPREAD ACROSS THE REGION WEDNESDAY NIGHT. LIGHT
NORTHERLY WINDS AND DECREASING CLOUDS WILL LEAD TO EXTREMELY COLD
LOWS IN THE TEENS BELOW ZERO ACROSS THE BULK OF THE FORECAST
AREA...WITH THE SINGLE DIGITS BELOW CLOSER TO THE MISSOURI RIVER.
WIND CHILLS WILL BE BRUTALLY COLD AROUND 20 TO 30 BELOW FOR A LARGE
AREA...BUT WINDS SHOULD REMAIN WELL BELOW THE 10 MPH THRESHOLD FOR A
WIND CHILL HEADLINE.
THURSDAY WILL AGAIN BE VERY COLD WITH LIGHT WINDS TURNING A LITTLE
MORE SOUTHERLY IN THE AFTERNOON AS SURFACE HIGH PRESSURE SLIPS OFF
TO OUR EAST. MOSTLY CLEAR SKIES IN THE MORNING WILL SEE AN INCREASE
IN CLOUD COVER FROM THE WEST LATER IN THE DAY AHEAD OF THE NEXT
INCOMING SHORTWAVE. TEMPERATURES WILL NOT WARM MUCH...WITH MANY
LOCATIONS ONLY REACHING HIGHS AROUND ZERO. RETURN FLOW INCREASES
THURSDAY NIGHT AND FRIDAY...LEADING INTO THE ONLY MILD DAY OF THE
PERIOD. AFTER A SLIGHT DIP IN TEMPERATURES THURSDAY EVENING...
TEMPERATURES SHOULD BEGIN RISING OVERNIGHT WHILE CLOUDS INCREASE.
SOUTHERLY WINDS BECOME BREEZY ON FRIDAY...ESPECIALLY ACROSS OUR
EASTERN HALF...HOWEVER HIGHS ARE EXPECTED TO IMPROVE SOME 20 DEGREES
OR MORE FROM THURSDAY HIGHS. BLOWING AND DRIFTING OF THE RECENT
SNOWFALL COULD BE A CONCERN AS THE WINDS INCREASE ON FRIDAY.
STRONG COLD FRONT DIVES ACROSS THE REGION ON FRIDAY NIGHT...BRINGING
THE NEXT CHANCE OF SOME LIGHT SNOW ALONG AND BEHIND THE FRONT. UPPER
LEVEL TROUGH SINKS SOUTH OF THE FORECAST AREA LATE SATURDAY
NIGHT...USHERING IN ANOTHER ARCTIC BLAST FOLLOWED BY A REINFORCING
SHOT OF COLD AIR LATE SUNDAY AND SUNDAY NIGHT. LOW TEMPERATURES WILL
BE BACK INTO THE TEENS BELOW ZERO SUNDAY NIGHT AND MONDAY
NIGHT...WITH HIGHS EXPECTED TO BE BELOW ZERO FOR THE MAJORITY OF THE
FORECAST AREA. NORTHWEST WINDS ARE EXPECTED TO BE BREEZY SUNDAY
NIGHT INTO MONDAY WHICH PLACES NEARLY THE ENTIRE FORECAST AREA
SQUARELY INTO WIND CHILL WARNING TERRITORY AND AS COLD AS 35 TO 45
BELOW ZERO.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 524 PM CST TUE DEC 31 2013
GENERALLY EXPECTING VFR CONDITIONS PRIOR TO 06Z...THEN LIGHT SNOW
IS EXPECTED TO DEVELOP AND OVERSPREAD THE AREA AFTER THAT...WITH
CEILINGS LOWERING INTO THE MVFR RANGE. THE BETTER CHANCES OF SNOW
WILL BE SOUTH OF INTERSTATE 90...FOCUSED THROUGH THE MISSOURI
RIVER CORRIDOR INTO NORTHWESTERN IOWA...WHERE VISIBILITIES COULD
DROP INTO THE IFR RANGE IN HEAVIER SNOW ACTIVITY. LIGHT SNOW IS
EXPECTED TO TAPER OFF AFTER 12Z ON WEDNESDAY...THOUGH WILL MOST
LIKELY HOLD ON TO LOWER CEILINGS THROUGH THE DAY.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WIND CHILL ADVISORY UNTIL 9 AM CST WEDNESDAY FOR SDZ038>040-
054>056.
MN...WIND CHILL ADVISORY UNTIL 9 AM CST WEDNESDAY FOR MNZ071-072-080-
081-089-090-097.
IA...WIND CHILL ADVISORY UNTIL 9 AM CST WEDNESDAY FOR IAZ002-003-013-
014.
NE...NONE.
&&
$$
UPDATE...JM
SHORT TERM...CHENARD
LONG TERM...
AVIATION...JM
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
532 PM MST TUE DEC 31 2013
.UPDATE...
ISSUED AT 530 PM MST TUE DEC 31 2013
DUAL-POL RADAR DATA SHOWING SOME SLEET FROM STURGIS TOWARD
PHILIP...SUPPORTED BY 00Z KUNR SOUNDING...SO WILL ADD TO UPDATED
FORECAST. 00Z KUNR SOUNDING AND LATEST RAP GUIDANCE SUPPORTS
CHANGEOVER TO ALL SNOW BY MID-EVENING. UPDATED FORECAST WILL ALSO
RAISE POPS TO BETTER MATCH LATEST RADAR LOOPS.
UPDATE ISSUED AT 353 PM MST TUE DEC 31 2013
CALL TO AREA SPOTTERS SHOWED A BAND OF SLEET/FREEZING RAIN FROM
SOUTHEAST MT INTO WESTERN MEADE COUNTY...INCLUDING THE I-90
CORRIDOR FROM STURGIS TO SPEARFISH TO MOORCROFT. 21Z RAP SHOWED
NARROW BAND OF MIXED PRECIPITATION POTENTIAL FOR THESE AREAS
THROUGH ABOUT 04Z...WHEN EVERYTHING SHOULD SHIFT TO -SN. HAVE
INTRODUCED THESE ELEMENTS TO FORECAST AND ISSUED HEADLINES FOR THE
APPROPRIATE AREAS.
&&
.SHORT TERM...THIS EVENING THROUGH WEDNESDAY NIGHT
ISSUED AT 208 PM MST TUE DEC 31 2013
UPPER LEVEL ANALYSIS SHOWS NORTHWEST FLOW OVER THE
NORTHERN PLAINS. SURFACE MAP HAS AN ARCTIC BOUNDARY STRETCHING FROM
MONTANA THROUGH THE CWA INTO NEBRASKA. WARMER TEMPS TO THE SOUTH OF
THE BOUNDARY ARE IN THE 30S...WITH TEMPS TO THE NORTH IN THE SINGLE
DIGITS. LOW STRATUS COVERS MUCH OF THE REGION...WITH RADAR
DISPLAYING SOME LIGHT SNOW SHOWERS. WINDS ARE LIGHT AND VARIABLE.
AS THE ARCTIC BOUNDARY SPREADS SOUTH TONIGHT AND A SHORTWAVE
APPROACHES FROM THE WEST...LIGHT SNOW WILL TRANSITION SOUTH WITH THE
BEST FRONTOGENESIS. GENERALLY A COUPLE ADDITIONAL INCHES OR LESS OF
SNOW IS EXPECTED TONIGHT...WITH THE GREATER AMOUNTS OVER PARTS OF
NORTHEAST WYOMING AND THE NORTHERN BLACK HILLS. LOWS WILL RANGE FROM
AROUND 5 BELOW ZERO ACROSS CENTRAL SD TO ABOUT 20 ABOVE ZERO FARTHER
WEST.
SURFACE HIGH PRESSURE WILL SLIDE ACROSS ND ON NEW YEAR`S DAY...AND THE
PRESSURE GRADIENT WILL TIGHTEN A LITTLE...CAUSING BREEZY NORTHWEST
WINDS ACROSS NORTHWEST SD. LIGHT SNOW WILL CONTINUE THROUGH MUCH OF
THE DAY...WITH MINIMAL ACCUMULATIONS MOST PLACES. THE FROUDE NUMBER
AROUND 1.5 INDICATES THE POSSIBILITY FOR UPSLOPE-ENHANCED SNOW OVER
THE NORTHERN HILLS...ACCUMULATING ANOTHER INCH OR TWO THERE. HIGHS
WILL RANGE FROM THE TEENS ACROSS CENTRAL SD TO THE LOWER 30S IN
SOUTHWEST SD AND NORTHEAST WY.
SNOW WILL DIMINISH AND SKIES WILL BEGIN TO CLEAR WEDNESDAY NIGHT.
LOWS WILL BE AROUND 10 BELOW TO 15 ABOVE ZERO.
&&
.LONG TERM...THURSDAY THROUGH TUESDAY
ISSUED AT 208 PM MST TUE DEC 31 2013
POWERFUL NORTHERN STREAM WILL CONTINUE TO DOMINATE THE
WEATHER IN THE PERIOD. MEAN CENTRAL CANADIAN POLAR VORTEX
WILL DRIVE ANOTHER SURGE OF ARCTIC AIR INTO THE REGION BY
SUNDAY...AS A LONG WAVE TROUGH ADVECTS ACROSS THE NW CONUS AND
PHASES WITH A PORTION OF THE POLAR LOW. PROGRESSIVE FLOW OVER THE
WESTERN ATLANTIC WILL SUPPORT ONLY A BRIEF STAY OF ARCTIC AIR
LOCALLY AS SEMI-ZONAL FLOW DEVELOPS ONCE AGAIN EARLY NEXT WEEK. MEAN
MODEL SOLUTIONS ARE SUGGESTING A POTENTIAL PATTERN CHANGE BY THE
MIDDLE OF NEXT WEEK WITH BREAKDOWN OF THE EASTERN PAC UPPER
RIDGE...ALLOWING A RETURN TO PROGRESSIVE FLOW OVER MUCH OF
NOAM...WITH THE POTENTIAL FOR A WARMER PATTERN AFTERWARD.
THUR-FRI...DEEP LAYER RIDGING AHEAD OF THE ADVECTING UPPER TROUGH
WILL SUPPORT STAUNCH WAA WITH WESTERLY FLOW SPREADING OVER THE
REGION. HAVE ADJUSTED TEMPS BOTH DAYS...WITH MILD CONDITIONS
EXPECTED OVER NE WY AND BH THUR...ALL PLACES FRIDAY AS FLOW
INCREASES AND MIXING SPREADS ACROSS THE SD PLAINS. 40S WILL BE
COMMON FRI...WITH 50S EXPECTED IN THE LEE OF THE BLACK
HILLS...INCLUDING RAPID CITY. THE RIDGE WILL SHIFT EAST FRIDAY
AFTERNOON...WITH A STRONG UPPER IMPULSE EXPECTED INTO THE
REGION...BRINGING INCREASING CHANCES FOR PRECIP...RAIN POSSIBLY AT
FIRST THEN TRANSITIONING TO SNOW FRIDAY EVENING. CONTINUED POP
MENTION IN THE PERIOD...OPTING FOR A MORNING MENTION OVER WY. ARCTIC
FRONT AND ASSOCIATED IMPULSE WILL ARRIVE SUN...WITH A CONTINUED POP
MENTION THEN. ALTHOUGH MOISTURE WILL BE SIGNIFICANTLY LACKING WITH
THIS SYSTEM...BEST CHANCES FOR ANY SNOW ACCUMS WILL BE OVER NE WY
AND THE NORTHERN BH. ARCTIC AIR WILL SURGE SOUTH ACROSS THE REGION
SUNDAY INTO MONDAY WITH VERY COLD TEMPS EXPECTED. MADE A SLIGHT DOWN
ADJUSTMENT TO TEMPS GIVEN BETTER MODEL AGREEMENT...ALTHOUGH CONCERNS
LINGER ON THE DEGREE OF CAA. WAA LOOKS TO ENSUE AS EARLY AS MON
AFTERNOON PER THE ECMWF...WITH A SLOW WARMUP ON TRACK THROUGH THE
MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 353 PM MST TUE DEC 31 2013
PRECIPITATION WILL OVERSPREAD THE AREA TONIGHT LEADING TO IFR
CIGS/VSBYS IN -SN...LIFR CONDITIONS LIKELY IN THE STRONGEST AREAS
OF -SN AND BLACK HILLS AREA. -FZRA/PL POSSIBLE THIS EVENING FROM
NORTHEAST WY INTO WEST CENTRAL SD.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL 5 AM MST WEDNESDAY FOR SDZ012-024-
025-072.
WY...WINTER WEATHER ADVISORY UNTIL 5 AM MST WEDNESDAY FOR WYZ056-057-
071.
&&
$$
UPDATE...HELGESON
SHORT TERM...POJORLIE
LONG TERM...JC
AVIATION...HELGESON
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
530 PM CST TUE DEC 31 2013
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 339 PM CST TUE DEC 31 2013
SNOW ASSOCIATED WITH TODAYS WAVE IS EXITING THE AREA...WITH JUST
SOME ISOLATED TO SCATTERED FLURRIES LINGERING. ANOTHER WAVE WILL RIDE
SOUTHEAST ALONG THE THERMAL GRADIENT TONIGHT. MODELS HAVE HAD GREAT
DIFFICULTY PINPOINTING WHERE THE BEST SNOW POTENTIAL WILL BE WITH
THIS WAVE...AND HOW MUCH QPF WILL FALL. THUS NEEDLESS TO SAY A LOW
CONFIDENCE FORECAST. BEST LARGE SCALE FORCING FROM THE WAVE SEEMS TO
GO TO OUR SOUTH. HOWEVER THE MID LEVEL FRONTAL BOUNDARY SHOULD BE
FURTHER NORTH...IN THE VICINITY OF THE MISSOURI RIVER VALLEY. LATEST
MODELS ARE TRENDING THE AREA OF SNOW FURTHER NORTH...CLOSER TO THE
REGION WHERE ISENTROPIC LIFT OVER THE MID LEVEL FRONT INTERACTS WITH
SOME OF THE LARGE SCALE FORCING. MODELS ALSO SHOWING SOME WEAK
INSTABILITY ABOVE THE FRONT...SUGGESTING WE COULD SEE SOME ENHANCED
BANDING. THE THERMAL PROFILE DOES FEATURE A DECENT SIZED AREA IN THE
DENDRITIC SNOW GROWTH ZONE...SUGGESTING RATIOS COULD END UP AROUND
15 TO 1. A CONSENSUS OF MODEL QPF VALUES SUGGEST 1 TO 2 INCHES IN
THE SNOW BAND...WITH ISOLATED AMOUNTS UP TO 3 INCHES IF RATIOS END
UP A BIT HIGHER. HOWEVER THE RUC...HRRR AND 18Z NAM ARE ALL MUCH
MORE AGGRESSIVE WITH QPF VALUES. THESE THREE WOULD SUGGEST A BAND OF
3 TO 5 INCHES. GIVEN THE LARGE SCALE FORCING...POTENTIAL BANDING AND
MODELS TRENDING UPWARD IN QPF...THIS CAN NOT BE COMPLETELY RULED
OUT. HOWEVER DO NOT WANT TO JUMP ON THIS AT THIS POINT GIVEN THE
REST OF THE GUIDANCE SUGGESTING LOWER AND THE MODEL INCONSISTENCY
FROM RUN TO RUN. THUS...TRENDED AMOUNTS UP...BUT ONLY TOWARDS MODEL
CONSENSUS...WHICH AT THIS TIME STILL SEEMS LIKE THE MORE LIKELY
SOLUTION.
THE NEXT QUESTION IS EXACTLY WHERE THIS BAND SETS UP. RIGHT
NOW ALMOST ALL GUIDANCE SUGGESTS THE MISSOURI RIVER VALLEY IS THE
MOST LIKELY LOCATION...WITH DECREASING AMOUNTS AS YOU GET TOWARDS
INTERSTATE 90. HOWEVER THE GEM AND HRRR ARE FURTHER NORTH...PUTTING
THE HIGHER AMOUNTS CLOSER TO OR JUST SOUTH OF INTERSTATE 90. FOR
THIS FORECAST PACKAGE WILL GO WITH THE MORE LIKELY SOLUTION ALONG
THE MISSOURI RIVER...BUT GIVEN THE RECENT NORTHWARD TRENDS CAN NOT
COMPLETELY RULE OUT THE HRRR AND GEM SOLUTION. SO FOR NOW...WILL
STICK WITH THE 1 TO 3 INCHES ALONG THE MISSOURI RIVER...DECREASING
TO AROUND AN INCH IN SIOUX FALLS AND LESS TO THE NORTH...BUT AS
MENTIONED ABOVE...EVENING SHIFT WILL NEED TO MONITOR TRENDS AND SEE
IF ADJUSTMENTS ARE NEEDED. EXPECT SNOW TO START AROUND 10 PM IN OUR
WEST...APPROACH SIOUX FALLS AND SIOUX CITY CLOSER TO MIDNIGHT...AND
SPENCER TO STORM LAKE AROUND 2 AM.
IT WILL BE A COLD ONE TONIGHT AS WELL WITH LOWS IN THE SINGLE DIGITS
BELOW ZERO NORTH OF INTERSTATE 90 AND SINGLE DIGITS ABOVE TO THE
SOUTH. KEPT THE TREND OF STAYING ON THE WARMER SIDE OF GUIDANCE
THOUGH...GIVEN THE CLOUD COVER AND AT LEAST A WEAKLY MIXED BOUNDARY
LAYER. WIND CHILLS WILL BE AROUND THE 20 BELOW ZERO ADVISORY CRITERIA
IN OUR NORTH. HOWEVER DECIDED TO HOLD OFF ON ONE AT THIS TIME...AS
WINDS SHOULD DROP OFF AFTER SUNSET AND GENERALLY BE UNDER 10
MPH...AND IF WINDS STAY UP MORE...TEMPERATURES WILL PROBABLY STAY A
BIT WARMER THAN FORECAST. THUS FEEL LIKE WIND CHILLS WILL HOVER A
FEW DEGREES EITHER SIDE OF 20 BELOW...AND GIVEN OUR COLD WINTER THUS
FAR...WILL NOT ISSUE ANOTHER ADVISORY AT THIS TIME. SNOW SHOULD EXIT
THE AREA FROM NORTHWEST TO SOUTHEAST ON WEDNESDAY MORNING...GIVING
WAY TO A MOSTLY CLOUDY DAY WITH JUST SOME SCATTERED FLURRIES. HIGHS
WILL WILL ONLY BE IN THE SINGLE DIGITS ABOVE AND BELOW ZERO WITH
WIND CHILLS LIKELY STAYING BELOW ZERO THROUGH THE DAY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 339 PM CST TUE DEC 31 2013
CONTINUED COLD WEATHER PATTERN LOCKED IN PLACE FOR THE MAJORITY OF
THE MID AND LONG RANGE FORECAST. PREDOMINATE NORTHWEST UPPER LEVEL
FLOW WILL USHER IN SEVERAL WAVES THROUGH THE PERIOD WHICH WILL
PROVIDE REINFORCING SHOTS OF ARCTIC AIR. THE FIRST BLAST OF COLD AIR
CONTINUES TO SPREAD ACROSS THE REGION WEDNESDAY NIGHT. LIGHT
NORTHERLY WINDS AND DECREASING CLOUDS WILL LEAD TO EXTREMELY COLD
LOWS IN THE TEENS BELOW ZERO ACROSS THE BULK OF THE FORECAST
AREA...WITH THE SINGLE DIGITS BELOW CLOSER TO THE MISSOURI RIVER.
WIND CHILLS WILL BE BRUTALLY COLD AROUND 20 TO 30 BELOW FOR A LARGE
AREA...BUT WINDS SHOULD REMAIN WELL BELOW THE 10 MPH THRESHOLD FOR A
WIND CHILL HEADLINE.
THURSDAY WILL AGAIN BE VERY COLD WITH LIGHT WINDS TURNING A LITTLE
MORE SOUTHERLY IN THE AFTERNOON AS SURFACE HIGH PRESSURE SLIPS OFF
TO OUR EAST. MOSTLY CLEAR SKIES IN THE MORNING WILL SEE AN INCREASE
IN CLOUD COVER FROM THE WEST LATER IN THE DAY AHEAD OF THE NEXT
INCOMING SHORTWAVE. TEMPERATURES WILL NOT WARM MUCH...WITH MANY
LOCATIONS ONLY REACHING HIGHS AROUND ZERO. RETURN FLOW INCREASES
THURSDAY NIGHT AND FRIDAY...LEADING INTO THE ONLY MILD DAY OF THE
PERIOD. AFTER A SLIGHT DIP IN TEMPERATURES THURSDAY EVENING...
TEMPERATURES SHOULD BEGIN RISING OVERNIGHT WHILE CLOUDS INCREASE.
SOUTHERLY WINDS BECOME BREEZY ON FRIDAY...ESPECIALLY ACROSS OUR
EASTERN HALF...HOWEVER HIGHS ARE EXPECTED TO IMPROVE SOME 20 DEGREES
OR MORE FROM THURSDAY HIGHS. BLOWING AND DRIFTING OF THE RECENT
SNOWFALL COULD BE A CONCERN AS THE WINDS INCREASE ON FRIDAY.
STRONG COLD FRONT DIVES ACROSS THE REGION ON FRIDAY NIGHT...BRINGING
THE NEXT CHANCE OF SOME LIGHT SNOW ALONG AND BEHIND THE FRONT. UPPER
LEVEL TROUGH SINKS SOUTH OF THE FORECAST AREA LATE SATURDAY
NIGHT...USHERING IN ANOTHER ARCTIC BLAST FOLLOWED BY A REINFORCING
SHOT OF COLD AIR LATE SUNDAY AND SUNDAY NIGHT. LOW TEMPERATURES WILL
BE BACK INTO THE TEENS BELOW ZERO SUNDAY NIGHT AND MONDAY
NIGHT...WITH HIGHS EXPECTED TO BE BELOW ZERO FOR THE MAJORITY OF THE
FORECAST AREA. NORTHWEST WINDS ARE EXPECTED TO BE BREEZY SUNDAY
NIGHT INTO MONDAY WHICH PLACES NEARLY THE ENTIRE FORECAST AREA
SQUARELY INTO WIND CHILL WARNING TERRITORY AND AS COLD AS 35 TO 45
BELOW ZERO.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 524 PM CST TUE DEC 31 2013
GENERALLY EXPECTING VFR CONDITIONS PRIOR TO 06Z...THEN LIGHT SNOW
IS EXPECTED TO DEVELOP AND OVERSPREAD THE AREA AFTER THAT...WITH
CEILINGS LOWERING INTO THE MVFR RANGE. THE BETTER CHANCES OF SNOW
WILL BE SOUTH OF INTERSTATE 90...FOCUSED THROUGH THE MISSOURI
RIVER CORRIDOR INTO NORTHWESTERN IOWA...WHERE VISIBILITIES COULD
DROP INTO THE IFR RANGE IN HEAVIER SNOW ACTIVITY. LIGHT SNOW IS
EXPECTED TO TAPER OFF AFTER 12Z ON WEDNESDAY...THOUGH WILL MOST
LIKELY HOLD ON TO LOWER CEILINGS THROUGH THE DAY.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...CHENARD
LONG TERM...
AVIATION...JM
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
619 PM CST TUE DEC 31 2013
.DISCUSSION...HAVE INCREASED POPS FOR THIS EVENING...ESPECIALLY
ACROSS SOUTHERN AND EASTERN HALVES OF CWA. STILL EXPECTING BULK
OF PRECIP TO SHIFT EAST BY LATE EVENING AND OVERNIGHT. ALSO
INCREASED AMOUNT OF CLOUD COVER FOR TONIGHT AND ADJUSTED HOURLY
TEMPERATURES. UPDATED PRODUCTS ALREADY OUT WITH AN ADDITIONAL
UPDATE POSSIBLE LATER THIS EVENING.
&&
.PREV DISCUSSION... /ISSUED 609 PM CST TUE DEC 31 2013/
DISCUSSION...UPDATED FOR 00Z AVIATION.
AVIATION...SHIELD OF LIGHT RAIN CONTINUES TO MOVE OFF TO THE
EAST AND NORTHEAST. LEANED TOWARDS HRRR SOLUTION IN SHIFTING
PRECIP EAST OF THE TERMINALS BY 02Z/03Z. A TRANSITION TO MVFR
CEILINGS WILL THEN TAKE PLACE LATER TONIGHT...AND POSSIBLY NOT
UNTIL WEDNESDAY MORNING AT VCT. MIXED SIGNALS AMONG THE GUIDANCE
WRT TO CLOUD AS MODELS VARY BETWEEN IFR/LIFR AND MVFR. CONFIDENCE
IS NOT HIGH ENOUGH YET TO INCLUDE CEILINGS THAT LOW SO KEPT FLIGHT
CONDITIONS IN THE MVFR CATEGORY. LIGHT RAIN COULD BE POSSIBLE
AGAIN ON WEDNESDAY...ESPECIALLY AT ALI/CRP...BUT CONFIDENCE IS
ALSO NOT HIGH ENOUGH TO INCLUDE IN THE TAFS ATTM.
PREV DISCUSSION... /ISSUED 406 PM CST TUE DEC 31 2013/
SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...AN UPPER LEVEL
TROUGH/ASSOCIATED 700-300MB Q-VECTOR CONVERGENCE/ISENTROPIC LIFT
(300K LEVEL) IS EXPECTED TO MOVE ACRS THE CWA/MSA DRG THE PERIOD
AND CONTRIBUTE TO MAINLY STRATIFORM PCPN TONIGHT/WEDNESDAY BEFORE
CONDITIONS IMPROVE FROM WEST TO EAST WEDNESDAY EVENING/NIGHT. BASED
ON CONDENSATION PRESSURE DEFICITS...EXPECT THE BULK OF THE PCPN
TO OCCUR OVER THE ERN CWA/MSA LATE TONIGHT/WEDNESDAY. IN RESPONSE
TO A DISTURBANCE PROGD BY DETERMINISTIC OUTPUT TO DEVELOP/MOVE
ACRS THE ROCKIES/PLAINS DRG THE PERIOD...A COLD FRONT IS EXPECTED
TO ENTER THE CWA LATE WEDNESDAY NIGHT. DO NOT ANTICIPATE MUCH
ADDITIONAL PCPN ALONG THIS BOUNDARY OWING TO INCREASING
CONDENSATION PRESSURE DEFICITS LATE WEDNESDAY IN ADVANCE OF THE
FRONT. NAM DETERMINISTIC VISIBILITY OUTPUT SUGGEST FOG WEDNESDAY
NIGHT IN ADVANCE OF THE FRONT. WL ONLY INTRODUCE PATCHY FOG FOR
THE 06-12Z THURSDAY PERIOD.
LONG TERM (THURSDAY THROUGH MONDAY NIGHT)...BEGINNING OF LONG TERM
PERIOD WILL SEE QUIETER WEATHER DEVELOPING BEHIND A COLD FRONT
PASSING LATE IN THE SHORT TERM PERIOD. SOME DISCREPANCIES IN MODEL
GUIDANCE AS TO HOW FAST CLOUDS WILL CLEAR BEHIND THE FRONT. HAVE
GONE A LITTLE CLOSER TO THE QUICKER CLEARING ECMWF...SHOULD SEE A
MAINLY SUNNY DAY ON THURSDAY ACROSS SOUTH TEXAS. MIN TEMPS THURSDAY
NIGHT COULD REACH FREEZING FOR SOME INLAND LOCATIONS. WILL DEPEND
ENTIRELY ON ANY LINGERING CLOUD COVER. BEST OPPORTUNITY FOR FREEZING
TEMPS WOULD BE WEST AND NORTH. BIG DIFFERENCES IN MOS GUIDANCE MIN
TEMPS (5-10 DEGREES)...WITH GFS COOLER THAN THE NAM DUE TO
DISCREPANCIES IN LOW LEVEL MOISTURE. HAVE CONTINUED WITH A COOL
TEMPERATURE FORECAST...BUT A BIT WARMER THAN PREVIOUS. HIGH PRESSURE
BUILDS BACK FOR FRIDAY WITH ONSHORE FLOW RESUMING. COULD SEE MAX
TEMPS APPROACH CLIMO NORMALS ON SATURDAY...FOR ONE DAY. WILL SEE A
BIT OF MOISTURE RETURN...BUT NOT TOO MUCH BEFORE THE NEXT FRONT
COMES THROUGH ON SUNDAY. COULD SEE SOME STREAMER SHOWERS DEVELOP
SATURDAY AND SUNDAY...BUT NOT EXPECT TOO MUCH WITH PWAT ONLY GETTING
BACK TO AROUND 1 INCH. LAPSE RATES STEEP ENOUGH THOUGH THAT COULD
SEE SOMETHING.
SOME TIMING ISSUES CONTINUE WITH SUNDAY COLD FRONT...BUT GETTING
BETTER. ECMWF FASTEST OF THE MODELS WITH GFS A FEW HOURS
BEHIND...AND CANADIAN A FEW MORE HOURS BEHIND. GENERALLY WE`RE
LOOKING FOR A MID MORNING TO EARLY AFTERNOON TIME FRAME. WITH LITTLE
MOISTURE AHEAD OF THE FRONT NOT EXPECTING ANYTHING IN THE WAY OF
CONVECTION AT THIS TIME. COULD SEE A COASTAL TROUGH DEVELOP EARLY
NEXT WEEK THAT WOULD BRING SOME MOISTURE BACK TO COASTAL AREAS. WILL
LIKELY SEE SLIGHT CHANCE POPS RETURN BY MID WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 41 62 44 57 36 / 40 30 10 10 0
VICTORIA 40 62 40 56 32 / 30 20 10 10 0
LAREDO 42 63 43 58 33 / 20 10 10 0 0
ALICE 41 62 44 58 33 / 40 20 10 10 0
ROCKPORT 44 61 46 56 41 / 40 30 20 10 0
COTULLA 40 63 40 58 31 / 10 10 10 0 0
KINGSVILLE 41 62 46 58 35 / 40 30 10 10 0
NAVY CORPUS 45 61 48 58 41 / 40 30 20 10 0
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
UPDATE...HART/79
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
609 PM CST TUE DEC 31 2013
.DISCUSSION...UPDATED FOR 00Z AVIATION.
&&
.AVIATION...SHIELD OF LIGHT RAIN CONTINUES TO MOVE OFF TO THE
EAST AND NORTHEAST. LEANED TOWARDS HRRR SOLUTION IN SHIFTING
PRECIP EAST OF THE TERMINALS BY 02Z/03Z. A TRANSITION TO MVFR
CEILINGS WILL THEN TAKE PLACE LATER TONIGHT...AND POSSIBLY NOT
UNTIL WEDNESDAY MORNING AT VCT. MIXED SIGNALS AMONG THE GUIDANCE
WRT TO CLOUD AS MODELS VARY BETWEEN IFR/LIFR AND MVFR. CONFIDENCE
IS NOT HIGH ENOUGH YET TO INCLUDE CEILINGS THAT LOW SO KEPT FLIGHT
CONDITIONS IN THE MVFR CATEGORY. LIGHT RAIN COULD BE POSSIBLE
AGAIN ON WEDNESDAY...ESPECIALLY AT ALI/CRP...BUT CONFIDENCE IS
ALSO NOT HIGH ENOUGH TO INCLUDE IN THE TAFS ATTM.
&&
.PREV DISCUSSION... /ISSUED 406 PM CST TUE DEC 31 2013/
SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...AN UPPER LEVEL
TROUGH/ASSOCIATED 700-300MB Q-VECTOR CONVERGENCE/ISENTROPIC LIFT
(300K LEVEL) IS EXPECTED TO MOVE ACRS THE CWA/MSA DRG THE PERIOD
AND CONTRIBUTE TO MAINLY STRATIFORM PCPN TONIGHT/WEDNESDAY BEFORE
CONDITIONS IMPROVE FROM WEST TO EAST WEDNESDAY EVENING/NIGHT. BASED
ON CONDENSATION PRESSURE DEFICITS...EXPECT THE BULK OF THE PCPN
TO OCCUR OVER THE ERN CWA/MSA LATE TONIGHT/WEDNESDAY. IN RESPONSE
TO A DISTURBANCE PROGD BY DETERMINISTIC OUTPUT TO DEVELOP/MOVE
ACRS THE ROCKIES/PLAINS DRG THE PERIOD...A COLD FRONT IS EXPECTED
TO ENTER THE CWA LATE WEDNESDAY NIGHT. DO NOT ANTICIPATE MUCH
ADDITIONAL PCPN ALONG THIS BOUNDARY OWING TO INCREASING
CONDENSATION PRESSURE DEFICITS LATE WEDNESDAY IN ADVANCE OF THE
FRONT. NAM DETERMINISTIC VISIBILITY OUTPUT SUGGEST FOG WEDNESDAY
NIGHT IN ADVANCE OF THE FRONT. WL ONLY INTRODUCE PATCHY FOG FOR
THE 06-12Z THURSDAY PERIOD.
LONG TERM (THURSDAY THROUGH MONDAY NIGHT)...BEGINNING OF LONG TERM
PERIOD WILL SEE QUIETER WEATHER DEVELOPING BEHIND A COLD FRONT
PASSING LATE IN THE SHORT TERM PERIOD. SOME DISCREPANCIES IN MODEL
GUIDANCE AS TO HOW FAST CLOUDS WILL CLEAR BEHIND THE FRONT. HAVE
GONE A LITTLE CLOSER TO THE QUICKER CLEARING ECMWF...SHOULD SEE A
MAINLY SUNNY DAY ON THURSDAY ACROSS SOUTH TEXAS. MIN TEMPS THURSDAY
NIGHT COULD REACH FREEZING FOR SOME INLAND LOCATIONS. WILL DEPEND
ENTIRELY ON ANY LINGERING CLOUD COVER. BEST OPPORTUNITY FOR FREEZING
TEMPS WOULD BE WEST AND NORTH. BIG DIFFERENCES IN MOS GUIDANCE MIN
TEMPS (5-10 DEGREES)...WITH GFS COOLER THAN THE NAM DUE TO
DISCREPANCIES IN LOW LEVEL MOISTURE. HAVE CONTINUED WITH A COOL
TEMPERATURE FORECAST...BUT A BIT WARMER THAN PREVIOUS. HIGH PRESSURE
BUILDS BACK FOR FRIDAY WITH ONSHORE FLOW RESUMING. COULD SEE MAX
TEMPS APPROACH CLIMO NORMALS ON SATURDAY...FOR ONE DAY. WILL SEE A
BIT OF MOISTURE RETURN...BUT NOT TOO MUCH BEFORE THE NEXT FRONT
COMES THROUGH ON SUNDAY. COULD SEE SOME STREAMER SHOWERS DEVELOP
SATURDAY AND SUNDAY...BUT NOT EXPECT TOO MUCH WITH PWAT ONLY GETTING
BACK TO AROUND 1 INCH. LAPSE RATES STEEP ENOUGH THOUGH THAT COULD
SEE SOMETHING.
SOME TIMING ISSUES CONTINUE WITH SUNDAY COLD FRONT...BUT GETTING
BETTER. ECMWF FASTEST OF THE MODELS WITH GFS A FEW HOURS
BEHIND...AND CANADIAN A FEW MORE HOURS BEHIND. GENERALLY WE`RE
LOOKING FOR A MID MORNING TO EARLY AFTERNOON TIME FRAME. WITH LITTLE
MOISTURE AHEAD OF THE FRONT NOT EXPECTING ANYTHING IN THE WAY OF
CONVECTION AT THIS TIME. COULD SEE A COASTAL TROUGH DEVELOP EARLY
NEXT WEEK THAT WOULD BRING SOME MOISTURE BACK TO COASTAL AREAS. WILL
LIKELY SEE SLIGHT CHANCE POPS RETURN BY MID WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 41 62 44 57 36 / 30 30 10 10 0
VICTORIA 40 62 40 56 32 / 20 20 10 10 0
LAREDO 42 63 43 58 33 / 20 10 10 0 0
ALICE 41 62 44 58 33 / 20 20 10 10 0
ROCKPORT 44 61 46 56 41 / 30 30 20 10 0
COTULLA 40 63 40 58 31 / 10 10 10 0 0
KINGSVILLE 41 62 46 58 35 / 30 30 10 10 0
NAVY CORPUS 45 61 48 58 41 / 30 30 20 10 0
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
TB/78...AVIATION
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
124 PM EST MON DEC 30 2013
.SYNOPSIS...
A COLD FRONT WILL PASS THROUGH OUR AREA EARLY TODAY...BEFORE
STALLING OVER THE CAROLINAS TOMORROW. A WEAK AREA OF LOW PRESSURE
IS EXPECTED TO FORM ON THIS FRONT...BRINGING LIGHT PRECIPITATION
TO SOUTHSIDE OF VIRGINIA AND THE NORTHERN PIEDMONT OF NORTH
CAROLINA TONIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 AM EST MONDAY...
RADAR INDICATES LIGHT SNOW SHOWER ACTIVITY MOVING ACROSS CENTRAL
AND SOUTHEAST WEST VIRGINIA THIS MORNING...LIKELY WITH MORE
ACTIVITY OCCURRING BELOW THE RADAR BEAM. REGARDLESS...PHONE CALLS
MADE TO SPOTTERS ACROSS SOUTHEAST WEST VIRGINIA HAVE YIELDED
REPORTS OF ON AND OFF SHOWER ACTIVITY...WITH LITTLE ACCUMULATION.
RADAR DOES INDICATE MORE WIDESPREAD ACTIVITY ACROSS SOUTHERN
OHIO...BUT LATEST RAP AND LOCAL WRF MODELS DO NOT HOLD THIS
ACTIVITY TOGETHER MUCH INTO THE AFTERNOON BEFORE WINDS BACK AHEAD
OF OUR NEXT UPPER LEVEL TROUGH. AS SUCH...HAVE TAILORED
ACCUMULATING SNOWFALL TIGHTLY TO THE UPSLOPE AREAS...MAINLY WITH A
TENTH TO QUARTER INCH ACCUMULATIONS FOR THIS AFTERNOON...WITH
FLURRIES ELSEWHERE.
EXPECT VERY LITTLE WARMING...IF ANY...FOR PORTIONS OF SOUTHEAST
WEST VIRGINIA AND THE MOUNTAIN EMPIRE THIS AFTERNOON AS COLDER AIR
BUILDS IN FROM THE WEST. HOWEVER...WITH THE COLD FRONT MAKING ONLY
SLOW PROGRESS EASTWARD FROM THE BLUE RIDGE THIS MORNING...EXPECT
PORTIONS OF THE SOUTHSIDE AND NORTH CENTRAL NORTH CAROLINA TO WARM
INTO THE UPPER 40S...ESPECIALLY IN AREAS WHERE CLOUDS BREAK OUT
FOR A SHORT WHILE.
A WEAK...BUT FAST MOVING...SOUTHERN STREAM SYSTEM ZIPS THROUGH
NORTH CAROLINA AND FAR SOUTHERN VIRGINIA TONIGHT. GFS AND ECWMF
MODELS DEVELOP LIGHT PRECIP AS STRONG UPPER LEVEL DIVERGENCE
DEVELOPS ALONG WITH SOME MID LEVEL EQUIV POT VORTICITY. FORECAST
SOUNDINGS ARE QUITE DRY BELOW 5KT FEET...SO THERE STILL REMAINS
SOME DOUBT WHETHER ENOUGH SATURATION IN THE LOW LEVELS CAN OCCUR
FOR MEASURABLE PRECIP. CONTINUED SMALL POPS IN THE NORTHERN NC
PIEDMONT AND VA SOUTHSIDE TONIGHT WITH PRECIP MAINLY IN THE FORM
OF RAIN...BUT A FEW FLAKES OF SNOW MIXED IN ARE NOT OUT OF THE
QUESTION. WITH PLENTY OF MID/HIGH LEVEL CLOUDS...LEANED TOWARD THE
WARMER ECMWF FORECAST LOWS TONIGHT.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
AS OF 315 AM EST MONDAY...
AN INTENSE POLAR VORTEX WILL BE ANCHORED OVER THE JAMES BAY REGION
MUCH OF THE MID-WEEK PERIOD WITH BITTERLY COLD AIR LOCKED IN ACROSS
SOUTHERN CANADA INTO NORTHERN NEW ENGLAND. MEANWHILE THE LOCAL
FORECAST AREA WILL REMAIN WELL SOUTH OF THIS STRONG BAROCLINIC ZONE
WITH WESTERLY FLOW ALOFT AND WEAK SURFACE RIDGING AND ONLY MODIFIED
POLAR AIR ACROSS THE REGION. WEATHER SHOULD BE BASICALLY TRANQUIL
WITH TEMPS CLOSE TO OR SLIGHTLY ABOVE LATE DECEMBER CLIMO...THOUGH
SLIGHTLY WARMER ON WEDNESDAY. THURSDAY LOOKS TO BE A TRANSITION DAY
BUT STILL FAIRLY MILD AHEAD OF AN APPROACHING STRONG COLD FRONT.
SIGNIFICANT MODEL DIFFERENCES ARISE AT THIS TIME AS WELL WITH 00Z/30
EURO SHOWING A MUCH DEEPER UPPER TROUGH AND DIGGING SHORTWAVE ALL
THE WAY SOUTH INTO THE LOWER MISS VALLEY AND WINDING UP A DEEPER
SURFACE LOW SUBSTANTIALLY FURTHER SOUTH THAN 00Z/30 GFS OR THE
PREVIOUS EURO WHICH WERE BOTH MUCH LESS AMPLIFIED. FOR THIS PACKAGE
BASICALLY HELD TO MORE OF GFS AND THE 12Z EURO KEEPING WEAKER
SURFACE LOW AND DEFORMATION PRECIP ZONE WELL NORTH OF CWA. AS USUAL
WILL BE AWAITING NEW MODEL RUNS TO ASSESS CONSISTENCY OF SOLUTIONS.
TIMING OF THE COLD FRONT CROSSING THE MOUNTAINS APPEARS TO BE
SOMETIME THURSDAY EVENING BEHIND WHATEVER SURFACE LOW DOES DEVELOP
AND A PIECE OF AT LEAST MODIFIED ARCTIC AIR IS BRIEFLY PULLED SOUTH
INTO THE CENTRAL/SOUTHERN APPALACHIANS BY EARLY FRIDAY MORNING WITH
BOTH EURO/GFS SHOWING H8 TEMPS DOWN TO -16C OVER THE NW CWA BY 12Z
FRIDAY. OF COURSE UPSLOPE SNOW MACHINE WILL BE STARTING UP IN THOSE
FAVORED LOCATIONS.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 345 PM EST SUNDAY...
LONG RANGE MODELS ARE STILL IN THE PROCESS OF RESOLVING HOW THE
ARRIVAL AND PASSAGE OF THE UPPER LEVEL TROUGH WILL AFFECT OUR
WEATHER HEADING INTO THE END OF THE COMING WORKWEEK. BOTH THE GFS
AND ECMWF MODELS ARE SIMILAR IN DEVELOPING A SURFACE LOW OFF OF
THE SOUTHEAST COAST...THEN ADVANCING THE LOW RAPIDLY NORTHEAST.
HOWEVER...THE GFS MODEL IS FASTER IN DEVELOPING THE LOW...MOVING
IT TO UPPER NEW ENGLAND BY THURSDAY EVENING...WHILE THE ECMWF IS 6
TO 12 HOURS SLOWER ALONG A SIMILAR TRACK. BOTH MODELS ALSO DEVELOP
A SECOND LOW PASSING SOUTH OF THE GREAT LAKES...WITH THE
ASSOCIATED COLD FRONT USHERING A SHOT OF ARCTIC AIR SOMETIME
THURSDAY NIGHT. AT THIS POINT...PREFER THE SLOWER ECMWF TIMING OF
THIS SYSTEM AS THE GFS TENDS TO RUN FAST. THE COASTAL LOW APPEARS
FAR ENOUGH EAST THAT WE SHOULD NOT SEE MUCH ASSOCIATED MOISTURE
ACROSS OUR AREA. THE ARRIVAL OF THE ARCTIC AIR ON THE OTHER HAND
WILL USHER IN ANOTHER ROUND OF MOUNTAIN SNOW SHOWERS AND GUSTY
NORTHWEST WINDS.
SNOW SHOWERS WILL DIMINISH FRIDAY AFTERNOON AS HIGH PRESSURE
PASSES OVERHEAD. FRIDAY WILL CERTAINLY BE ON THE CHILLY SIDE AS
THE UPPER TROUGH PASSES OVERHEAD...AND DO NOT EXPECT MUCH OF OUR
AREA TO CLIMB ABOVE FREEZING FOR AFTERNOON HIGHS. HIGH PRESSURE
WILL BECOME WEDGED AGAINST THE EASTERN FACE OF THE APPALACHIANS
FOR SATURDAY. EXPECT SLIGHTLY WARMER TEMPERATURES FOR SATURDAY AS
THE UPPER TROUGH SLIDES EAST.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 115 PM EST MONDAY...
A FEW POCKETS OF SNOW SHOWER ACTIVITY EXIST IN SOUTHEAST WEST
VIRGINIA PER AREA METARS...HOWEVER MUCH OF WHATEVER IS OUT THERE
IS OCCURRING BELOW THE RADAR BEAM. AS SUCH...EXPECT TEMPORARY
REDUCTIONS IN VISIBILITY AT BLF AND OTHER NEARBY LOCAL AIRPORTS AS
THESE SHOWERS PASS OVERHEAD...WITH SNOW SHOWER ACTIVITY
DIMINISHING THROUGH EARLY EVENING.
GUSTY NORTHWESTERLY FLOW WILL ALSO MAINTAIN LOW STRATOCU ACROSS
THE MOUNTAINS THROUGH THE REMAINDER OF THE AFTERNOON...WITH
CEILINGS BELOW 1KFT AT BLF...AND IN THE 2KFT TO 3KFT RANGE AT BCB
AND LWB. CEILINGS INCREASE TO 4KFT OR HIGHER EAST OF THE BLUE
RIDGE. WHILE LOW CLOUDS WILL GRADUALLY DIMINISH THIS EVENING AS
HIGH PRESSURE BUILDS IN...MID AND HIGH CLOUDS WILL PERSIST AS AN
UPPER LEVEL TROUGH APPROACHES FROM THE WEST.
THE UPPER LEVEL TROUGH WILL TRIGGER A LIGHT/BRIEF RAIN AND SNOW
MIX OVERNIGHT MAINLY FOR DAN...POSSIBLY AS FAR NORTH AS ROA AND
LYH. MAY SEE A FEW REDUCTIONS IN VISIBILITY AT DAN AS THE
PRECIPITATION PASSES...BUT DO NOT EXPECT ANY ACCUMULATIONS.
PRECIPITATION IS EXPECTED TO BE EAST OF THE AREA BY SUNRISE
TUESDAY.
SKIES WILL CLEAR FOR TUESDAY AFTERNOON AS THE TROUGH PASSES
EAST...WITH GRADIENT WEST NORTHWEST WINDS PICKING UP DURING LATE
MORNING. EXPECT 20KT TO 25KT GUSTS DURING THE AFTERNOON MOST
LOCATIONS... APPROACHING 30KT AT ROA.
EXTENDED AVIATION DISCUSSION...A SERIES OF CLIPPER SYSTEMS AND
REINFORCING SHOTS OF ARCTIC AIR ARE EXPECTED IN THE DAYS FOLLOWING
THROUGH NEW YEARS AND THE END OF NEXT WEEK. EACH OF THESE SYSTEMS
WILL BRING MOUNTAIN UPSLOPE -SHSN...AFFECTING PRINCIPALLY BLF AND
LWB.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...PH
NEAR TERM...NF/PH
SHORT TERM...PC
LONG TERM...NF
AVIATION...NF/PH
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1051 AM EST MON DEC 30 2013
.SYNOPSIS...
A COLD FRONT WILL PASS THROUGH OUR AREA EARLY TODAY...BEFORE
STALLING OVER THE CAROLINAS TOMORROW. A WEAK AREA OF LOW PRESSURE
IS EXPECTED TO FORM ON THIS FRONT...BRINGING LIGHT PRECIPITATION
TO SOUTHSIDE OF VIRGINIA AND THE NORTHERN PIEDMONT OF NORTH
CAROLINA TONIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM EST MONDAY...
RADAR INDICATES LIGHT SNOW SHOWER ACTIVITY MOVING ACROSS CENTRAL
AND SOUTHEAST WEST VIRGINIA THIS MORNING...LIKELY WITH MORE
ACTIVITY OCCURRING BELOW THE RADAR BEAM. REGARDLESS...PHONE CALLS
MADE TO SPOTTERS ACROSS SOUTHEAST WEST VIRGINIA HAVE YIELDED
REPORTS OF ON AND OFF SHOWER ACTIVITY...WITH LITTLE ACCUMULATION.
RADAR DOES INDICATE MORE WIDESPREAD ACTIVITY ACROSS SOUTHERN
OHIO...BUT LATEST RAP AND LOCAL WRF MODELS DO NOT HOLD THIS
ACTIVITY TOGETHER MUCH INTO THE AFTERNOON BEFORE WINDS BACK AHEAD
OF OUR NEXT UPPER LEVEL TROUGH. AS SUCH...HAVE TAILORED
ACCUMULATING SNOWFALL TIGHTLY TO THE UPSLOPE AREAS...MAINLY WITH A
TENTH TO QUARTER INCH ACCUMULATIONS FOR THIS AFTERNOON...WITH
FLURRIES ELSEWHERE.
EXPECT VERY LITTLE WARMING...IF ANY...FOR PORTIONS OF SOUTHEAST
WEST VIRGINIA AND THE MOUNTAIN EMPIRE THIS AFTERNOON AS COLDER AIR
BUILDS IN FROM THE WEST. HOWEVER...WITH THE COLD FRONT MAKING ONLY
SLOW PROGRESS EASTWARD FROM THE BLUE RIDGE THIS MORNING...EXPECT
PORTIONS OF THE SOUTHSIDE AND NORTH CENTRAL NORTH CAROLINA TO WARM
INTO THE UPPER 40S...ESPECIALLY IN AREAS WHERE CLOUDS BREAK OUT
FOR A SHORT WHILE.
A WEAK...BUT FAST MOVING...SOUTHERN STREAM SYSTEM ZIPS THROUGH
NORTH CAROLINA AND FAR SOUTHERN VIRGINIA TONIGHT. GFS AND ECWMF
MODELS DEVELOP LIGHT PRECIP AS STRONG UPPER LEVEL DIVERGENCE
DEVELOPS ALONG WITH SOME MID LEVEL EQUIV POT VORTICITY. FORECAST
SOUNDINGS ARE QUITE DRY BELOW 5KT FEET...SO THERE STILL REMAINS
SOME DOUBT WHETHER ENOUGH SATURATION IN THE LOW LEVELS CAN OCCUR
FOR MEASURABLE PRECIP. CONTINUED SMALL POPS IN THE NORTHERN NC
PIEDMONT AND VA SOUTHSIDE TONIGHT WITH PRECIP MAINLY IN THE FORM
OF RAIN...BUT A FEW FLAKES OF SNOW MIXED IN ARE NOT OUT OF THE
QUESTION. WITH PLENTY OF MID/HIGH LEVEL CLOUDS...LEANED TOWARD THE
WARMER ECMWF FORECAST LOWS TONIGHT.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
AS OF 315 AM EST MONDAY...
AN INTENSE POLAR VORTEX WILL BE ANCHORED OVER THE JAMES BAY REGION
MUCH OF THE MID-WEEK PERIOD WITH BITTERLY COLD AIR LOCKED IN ACROSS
SOUTHERN CANADA INTO NORTHERN NEW ENGLAND. MEANWHILE THE LOCAL
FORECAST AREA WILL REMAIN WELL SOUTH OF THIS STRONG BAROCLINIC ZONE
WITH WESTERLY FLOW ALOFT AND WEAK SURFACE RIDGING AND ONLY MODIFIED
POLAR AIR ACROSS THE REGION. WEATHER SHOULD BE BASICALLY TRANQUIL
WITH TEMPS CLOSE TO OR SLIGHTLY ABOVE LATE DECEMBER CLIMO...THOUGH
SLIGHTLY WARMER ON WEDNESDAY. THURSDAY LOOKS TO BE A TRANSITION DAY
BUT STILL FAIRLY MILD AHEAD OF AN APPROACHING STRONG COLD FRONT.
SIGNIFICANT MODEL DIFFERENCES ARISE AT THIS TIME AS WELL WITH 00Z/30
EURO SHOWING A MUCH DEEPER UPPER TROUGH AND DIGGING SHORTWAVE ALL
THE WAY SOUTH INTO THE LOWER MISS VALLEY AND WINDING UP A DEEPER
SURFACE LOW SUBSTANTIALLY FURTHER SOUTH THAN 00Z/30 GFS OR THE
PREVIOUS EURO WHICH WERE BOTH MUCH LESS AMPLIFIED. FOR THIS PACKAGE
BASICALLY HELD TO MORE OF GFS AND THE 12Z EURO KEEPING WEAKER
SURFACE LOW AND DEFORMATION PRECIP ZONE WELL NORTH OF CWA. AS USUAL
WILL BE AWAITING NEW MODEL RUNS TO ASSESS CONSISTENCY OF SOLUTIONS.
TIMING OF THE COLD FRONT CROSSING THE MOUNTAINS APPEARS TO BE
SOMETIME THURSDAY EVENING BEHIND WHATEVER SURFACE LOW DOES DEVELOP
AND A PIECE OF AT LEAST MODIFIED ARCTIC AIR IS BRIEFLY PULLED SOUTH
INTO THE CENTRAL/SOUTHERN APPALACHIANS BY EARLY FRIDAY MORNING WITH
BOTH EURO/GFS SHOWING H8 TEMPS DOWN TO -16C OVER THE NW CWA BY 12Z
FRIDAY. OF COURSE UPSLOPE SNOW MACHINE WILL BE STARTING UP IN THOSE
FAVORED LOCATIONS.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 345 PM EST SUNDAY...
LONG RANGE MODELS ARE STILL IN THE PROCESS OF RESOLVING HOW THE
ARRIVAL AND PASSAGE OF THE UPPER LEVEL TROUGH WILL AFFECT OUR
WEATHER HEADING INTO THE END OF THE COMING WORKWEEK. BOTH THE GFS
AND ECMWF MODELS ARE SIMILAR IN DEVELOPING A SURFACE LOW OFF OF
THE SOUTHEAST COAST...THEN ADVANCING THE LOW RAPIDLY NORTHEAST.
HOWEVER...THE GFS MODEL IS FASTER IN DEVELOPING THE LOW...MOVING
IT TO UPPER NEW ENGLAND BY THURSDAY EVENING...WHILE THE ECMWF IS 6
TO 12 HOURS SLOWER ALONG A SIMILAR TRACK. BOTH MODELS ALSO DEVELOP
A SECOND LOW PASSING SOUTH OF THE GREAT LAKES...WITH THE
ASSOCIATED COLD FRONT USHERING A SHOT OF ARCTIC AIR SOMETIME
THURSDAY NIGHT. AT THIS POINT...PREFER THE SLOWER ECMWF TIMING OF
THIS SYSTEM AS THE GFS TENDS TO RUN FAST. THE COASTAL LOW APPEARS
FAR ENOUGH EAST THAT WE SHOULD NOT SEE MUCH ASSOCIATED MOISTURE
ACROSS OUR AREA. THE ARRIVAL OF THE ARCTIC AIR ON THE OTHER HAND
WILL USHER IN ANOTHER ROUND OF MOUNTAIN SNOW SHOWERS AND GUSTY
NORTHWEST WINDS.
SNOW SHOWERS WILL DIMINISH FRIDAY AFTERNOON AS HIGH PRESSURE
PASSES OVERHEAD. FRIDAY WILL CERTAINLY BE ON THE CHILLY SIDE AS
THE UPPER TROUGH PASSES OVERHEAD...AND DO NOT EXPECT MUCH OF OUR
AREA TO CLIMB ABOVE FREEZING FOR AFTERNOON HIGHS. HIGH PRESSURE
WILL BECOME WEDGED AGAINST THE EASTERN FACE OF THE APPALACHIANS
FOR SATURDAY. EXPECT SLIGHTLY WARMER TEMPERATURES FOR SATURDAY AS
THE UPPER TROUGH SLIDES EAST.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
AS OF 615 AM EST MONDAY...
VFR CONDITIONS WERE OBSERVED EAST OF THE BLUE RIDGE...WHILE MVFR
TO IFR CONDITIONS WERE FOUND AT KBCB...KLWB AND KBLF. PATCHY AREAS
OF LIGHT RAIN OR DRIZZLE WERE NOTED AHEAD OF A COLD FRONT IN THE
FAR WESTERN PORTION OF OUR AREA...AS THE FRONT PASSES THIS MORNING
AND STRONG COLD AIR ADVECTION FORMS IN ITS WAKE...PRECIPITATION
WILL CHANGE TO -SHSN ALONG THE WESTERN SLOPES AND CONTINUE INTO
THE AFTERNOON. FOR KROA...KLYH AND KDAN...HIGH AND MID LEVEL
CLOUDS WILL INCREASE LATE THIS AFTERNOON AND THIS EVENING AS A
SOUTHERN STREAM SYSTEM APPROACHES. NO MEASURABLE PRECIPITATION IS
EXPECTED WITH THIS SYSTEM.
WINDS ILL BE WNW THROUGH THE TAF VALID PERIOD...AND WILL BE GUSTY
AT TIMES THROUGH 18Z. GUSTS TO 20-20KTS WILL BE POSSIBLE.
AVERAGE.
MEDIUM CONFIDENCE IN CIGS THROUGH THE TAF VALID PERIOD. MEDIUM
CONFIDENCE IN VSBYS BLF AND LWB THROUGH THE TAF VALID
PERIOD...HIGH CONFIDENCE IN VFR VSBYS ELSEWHERE. HIGH CONFIDENCE
IN WIND SPD/DIR THROUGH THE TAF VALID PERIOD.
EXTENDED AVIATION DISCUSSION...A SERIES OF CLIPPER SYSTEMS AND
REINFORCING SHOTS OF ARCTIC AIR ARE EXPECTED IN THE DAYS FOLLOWING
THROUGH NEW YEARS AND THE END OF NEXT WEEK. EACH OF THESE SYSTEMS
WILL BRING MOUNTAIN UPSLOPE -SHSN...AFFECTING PRINCIPALLY BLF AND
LWB.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...PH
NEAR TERM...NF/PH
SHORT TERM...PC
LONG TERM...NF
AVIATION...PH/RAB
AREA FORECAST DISCUSSION
NWS SPOKANE WA
524 PM PST Tue Dec 31 2013
.SYNOPSIS...
Weak high pressure will move over the Inland Northwest through
Wednesday although a few lingering areas of light rain and snow
will remain possible mainly in the Idaho Panhandle. A stronger
storm system will pass through Thursday night bringing mainly rain
in the valleys and snow in the mountains. A cooler and drier
pattern is expected this weekend into early next week.
&&
.DISCUSSION...
Update: A shortwave disturbance has slid into the central ID
Panhandle early this evening. The RUC model seems to have a good
handle on this piece of energy and slides it southeast of the
region by 8:00 PM tonight. Radar imagery already shows showers
across the area winding down as drier air aloft filters into the
region behind this disturbance. I expect this drying trend to
continue and updated the forecast to trend down our precip chances
through tonight. The only area expected to see some light snow
will be in the Central Panhandle Mountains, but will not be of
much concern. Other forecast updates were to expend the fog threat
to the south a bit faster and to include the Palouse region. The
L-C Valley is a tougher call for fog tonight as their dew point
depression is still a bit high. With temperatures remaining around
the freezing mark, any dense fog that forms will have the potential
for creating slick travel conditions. /SVH
&&
.AVIATION...
00Z TAFS: Weak disturbance working its way down southeast through
the aviation area will primarily light snow through early evening.
Then the high pressure amplifies and pushes storm track to the
north and east and away from the aviation area. The result may
very well be a repeat/continuation of low clouds and fog overnight
and into tomorrow morning with associated lowering of ceilings and
visibilities into IFR/LIFR category. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 26 36 28 38 31 38 / 10 10 10 20 70 20
Coeur d`Alene 29 38 27 40 30 37 / 10 10 10 20 80 30
Pullman 30 40 29 41 32 39 / 10 10 0 10 70 40
Lewiston 31 41 31 45 35 45 / 10 10 0 10 50 40
Colville 25 33 27 33 29 35 / 10 20 30 30 60 20
Sandpoint 28 36 27 37 29 37 / 10 20 30 40 90 30
Kellogg 31 37 29 38 31 35 / 50 20 20 30 90 60
Moses Lake 22 35 26 36 25 40 / 0 0 10 10 20 10
Wenatchee 26 36 27 36 27 40 / 0 0 0 10 20 10
Omak 22 32 25 32 24 36 / 0 10 10 20 30 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...Air Stagnation Advisory until Noon PST Friday for East Slopes
Northern Cascades-Moses Lake Area-Northeast Mountains-
Okanogan Highlands-Okanogan Valley-Spokane Area-Upper
Columbia Basin-Waterville Plateau-Wenatchee Area.
&&
$$
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1256 AM MST WED JAN 1 2014
.UPDATE...LATEST DATA SHOWS A FRONTAL SURGE MAYBE ENHANCED BY
PRECIPITATION NOW ADVANCING SOUTH TOWARD THE CO/WYOMING BORDER. AS
A RESULT...THIS SURGE SHOULD BE THROUGH THE I-70 CORRIDOR BEFORE
DAYBREAK SO HAVE INCREASED POPS BASED ON RAP13 GUIDANCE. THIS
MODELS SEEMS TO BE DOING BEST SO FAR WITH THE PROGRESSION OF
PRECIPITATION ON THE PLAINS. THIS WOULD RESULT IN BETTER CHANCES
OF SNOW FOR THE DENVER AREA AS WELL WITH FAVORABLE JET POSITION AND
Q-G LIFT THROUGH EARLY WEDNESDAY MORNING.
ALSO ADDED A RAIN/SNOW MIX OVER THE PLAINS IN THE PRE-DAWN HOURS
GIVEN WARMTH OF LOW LEVELS AND MIXING BEFORE STRONGER COLD ADVECTION
OCCURS.
&&
.AVIATION...MAY HAVE TO SPEED UP SNOW ARRIVAL AS EARLY AS 12Z
BASED ON LATEST FRONTAL MOVEMENT AND RADAR TRENDS TO OUR NORTH.
BETTER CHANCE WE COULD SEE AN INCH OF SNOW ACCUMULATION EARLY
WEDNESDAY MORNING AT KDEN AND KAPA. STILL THREAT OF SNOW SHOWERS
THROUGH WEDNESDAY AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 917 PM MST TUE DEC 31 2013/
UPDATE...
SHORT TERM...WATCHING THE PROGRESSION OF THE NEXT UPPER LEVEL
WAVE NOW OVER THE NORTHERN ROCKY MOUNTAIN REGION. SURFACE COLD
FRONT OVER NORTHERN WYOMING WITH A WEAK PRESSURE RISE ACROSS
SOUTHERN MONTANA AS SOME OBSERVATIONS SITES ARE SHOWING SOME LIGHT
SNOW. HAVE DELAYED AND TRIMMED BACK SNOW CHANCES OVER THE
NORTHEAST PLAINS TONIGHT ESPECIALLY OVER THE URBAN CORRIDOR AND
SECTIONS SOUTH OVER THE PALMER DIVIDE. STILL SOME QUESTION ABOUT
SNOW CHANCES OVER THE FRONT RANGE ON WEDNESDAY AS MOISTURE WILL BE
FIGHTING THE DRYING...POTENTIAL DOWNSLOPE FLOW TRYING TO DEVELOP.
THE NAM IS MOST PRONOUNCED WITH DRIER OF THE MODELS. THE RAP WAS
DRY IN EARLIER RUNS WITH MORE DOWNSLOPE...BUT NOW IS SHOWING MORE
UPSLOPE AND MOISTURE. FORECAST SOUNDINGS DO SHOW SOME
INSTABILITY...WHILE QG FIELDS DO SHOW SOME MODEST UPWARD ASCENT
AND WITH THE JET AROUND...HARD TO GO TOO DRY. WILL CONTINUE TO
TWEAK TIMING AND SNOW CHANCES TO CURRENT GRIDS.
AVIATION...MAY HAVE TO ADJUST TIMING AGAIN FOR EARLIER CHANCES OF
SNOW FORM CURRENT TIMING BASED ON LATEST DATA. LATEST TIMING WITH
FRONT INTO DEN NOW AROUND 12-13Z AND POTENTIAL FOR SOME SNOW
BETWEEN 15-21Z. STILL LOOKS LIKE SNOW ACCUMULATION WOULD BE AN
INCH OR LESS...MAINLY AT DEN AND LESSER CHANCES AT BJC.
PREV DISCUSSION... /ISSUED 256 PM MST TUE DEC 31 2013/
SHORT TERM...THERE ARE NORTHWEST WINDS OVER MOST OF THE PLAINS
.WITH SOME GUSTS OVER THE NORTHEAST CORNER UP TO 25 KNOTS.
NEARLY ALL THE CWA EAST OF THE HIGH MOUNTAINS IS NEARLY CLEAR OF
CLOUD COVER. THE CLOUD SHIELD ASSOCIATED WITH THE NEXT STORM IS
JUST UPSTREAM ACCORDING THE CURRENT SATELLITE PICTURES. NEAR IN
THE IMMEDIATE UPSTREAM. MODELS BRING THE APPROACHING TROUGH AXIS
ACROSS THE CWA FROM ABOUT 12Z-18Z WEDNESDAY MORNING. A NORTH-
NORTHWESTERLY ORIENTED JET MAXIMUM IS PROGGED OVER THE CENTRAL CWA
AT 00Z LATE WEDNESDAY AFTERNOON. THE QG VERTICAL VELOCITY FIELDS
SHOW UPWARD MOTION FOR THE CWA THIS EVENING THROUGH WEDNESDAY
MORNING. IT IS PROGGED TO BE PRETTY STRONG AROUND 12Z WEDNESDAY
MORNING. IT IS STRONGER THAN THE LAST TWO DISTURBANCES...LAST
SATURDAY NIGHT AND LAST NIGHT. THE BOUNDARY LAYER FLOW IS PRETTY
DECENT DOWNSLOPE THIS EVENING...WITH A FRONT AND UPSLOPE BEHIND IT
TO MOVE SOUTHWARD FROM 09Z TO 12Z. THE UPSLOPE COVERS THE PLAINS
AND LOWER FOOTHILLS THROUGH 18Z TOMORROW ...WITH DOWNSLOPING
NORTHWESTERLIES AFTER THAT. THERE IS A BIT OF A INVERTED TROUGH
ALONG THE FOOTHILLS/PLAINS INTERFACE. FOR MOISTURE...IS BEST ON
THE GFS...BUT THE NAM AND ECMWF DO HAVE SOME. IT EXISTS QUICKLY
WEDNESDAY AFTERNOON AND THE FOOTHILLS AND IMMEDIATE PLAINS SEEM TO
LACK SOME FROM THE DOWNSLOPING. THE QPF FIELDS HAVE SOME
MEASURABLE SNOWFALL FOR THE MOUNTAINS TONIGHT AND WEDNESDAY...WITH
MINIMAL AMOUNTS OVER THE PLAINS FROM 12Z TO 00Z ON WEDNESDAY. FOR
POPS...WILL STAY THE COURSE FOR THE MOST PART AND KEEP THE
ADVISORIES GOING IN THE HIGH MOUNTAINS OVERNIGHT INTO WEDNESDAY.
FOR THE PLAINS...THE BEST POPS WILL BE OVER THE EASTERN TWO-
THIRDS OF THEM. WILL NOT GO "LIKELY"S OVER THE PLAINS WITH THE LOW
LEVEL WINDS NOT SHOWING DECENT ENOUGH AND LONG ENOUGH UPSLOPE. FOR
TEMPERATURES...WEDNESDAY`S HIGHS ARE 5 TO 10 C COLDER THAN THIS
AFTERNOON`S.
LONG TERM...A PERSISTENT NORTHWEST FLOW PATTERN WILL CONTINUE TO
BRING UNSETTLED WEATHER TO THE REGION. THE SYSTEM ON TUESDAY AND
WEDNESDAY WILL MOVE THROUGH AND WILL BE REPLACED BY SURFACE HIGH
PRESSURE AND RIDGING. TEMPERATURES WILL INCREASE AND BE WARMEST
THURSDAY AND FRIDAY. THE ECMWF BRINGS THE NEXT DISTURBANCE IN JUST
AHEAD OF THE GFS BUT HAS COLD AIR MOVING IN LATER IN THE DAY AND
HAS HIGHER SNOWFALL AMOUNTS OVER MUCH OF THE REGION. THE GFS HAS
PRECIP CENTERED MORE OVER THE MOUNTAINS AND PLAINS WITH THE FRONT
MOVING IN FROM THE EAST AND DOWNSLOPING RIGHT ALONG THE FOOTHILLS
HELPING TO KEEP MUCH OF THE SNOW AWAY FROM THE FRONT RANGE.
HOWEVER, I WOULD NOT COUNT OUT SNOW FOR THE FRONT RANGE FOOTHILLS
AS BANDED PRECIPITATION WILL BE POSSIBLE WITH THE PLACEMENT OF THE
UPPER LEVEL JET THAT COULD COUNTERACT THE DOWNSLOPE FLOW.
CONTINUED JET SUPPORT COMBINED WITH EMBEDDED DISTURBANCES WITHIN
THE FLOW WILL KEEP TEMPERATURES COOLER WITH HIGHS GETTING BACK
INTO THE UPPER 20S AND 40S THROUGH TUESDAY AS WELL AS A SLIGHT
CHANCE OF SNOW OVER THE REGION. INCREASED WINDS WITH THE NORTHWEST
FLOW WILL ALSO BE POSSIBLE ALONG THE NORTHERN MOUNTAINS AND
FOOTHILLS LATER IN THE PERIOD.
AVIATION...NORTHWESTERLIES ARE PRETTY GOOD NOW AT DIA. WE SHOULD
GO TO DRAINAGE SHORTLY AFTER SUNSET...THEN GET A BIT OF WESTERLY
COMPONENT TO THEM AFTER 05Z. WILL BRING UPSLOPE WIND SHIFT IN
ABOUT 11Z. CEILING WILL BECOME AN ISSUE BY 12Z. THEY COULD GET AS
LOW AS 1000 AGL. SNOW ONLY IN PROB30 GROUP NOW...BUT PERHAPS A
TEMPO GROUP WILL BE NEEDED. WOULD NOT PUT IT IN THE PREDOMINANT
PERIOD OF THE TAF AT THIS TIME.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON MST TODAY FOR COZ031-033-034.
&&
$$
SHORT TERM...BARJENBRUCH
LONG TERM....BOWEN
AVIATION...BARJENBRUCH
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
917 PM MST TUE DEC 31 2013
.UPDATE...
&&
.SHORT TERM...WATCHING THE PROGRESSION OF THE NEXT UPPER LEVEL
WAVE NOW OVER THE NORTHERN ROCKY MOUNTAIN REGION. SURFACE COLD
FRONT OVER NORTHERN WYOMING WITH A WEAK PRESSURE RISE ACROSS
SOUTHERN MONTANA AS SOME OBSERVATIONS SITES ARE SHOWING SOME LIGHT
SNOW. HAVE DELAYED AND TRIMMED BACK SNOW CHANCES OVER THE
NORTHEAST PLAINS TONIGHT ESPECIALLY OVER THE URBAN CORRIDOR AND
SECTIONS SOUTH OVER THE PALMER DIVIDE. STILL SOME QUESTION ABOUT
SNOW CHANCES OVER THE FRONT RANGE ON WEDNESDAY AS MOISTURE WILL BE
FIGHTING THE DRYING...POTENTIAL DOWNSLOPE FLOW TRYING TO DEVELOP.
THE NAM IS MOST PRONOUNCED WITH DRIER OF THE MODELS. THE RAP WAS
DRY IN EARLIER RUNS WITH MORE DOWNSLOPE...BUT NOW IS SHOWING MORE
UPSLOPE AND MOISTURE. FORECAST SOUNDINGS DO SHOW SOME
INSTABILITY...WHILE QG FIELDS DO SHOW SOME MODEST UPWARD ASCENT
AND WITH THE JET AROUND...HARD TO GO TOO DRY. WILL CONTINUE TO
TWEAK TIMING AND SNOW CHANCES TO CURRENT GRIDS.
.AVIATION...MAY HAVE TO ADJUST TIMING AGAIN FOR EARLIER CHANCES OF
SNOW FORM CURRENT TIMING BASED ON LATEST DATA. LATEST TIMING WITH
FRONT INTO DEN NOW AROUND 12-13Z AND POTENTIAL FOR SOME SNOW
BETWEEN 15-21Z. STILL LOOKS LIKE SNOW ACCUMULATION WOULD BE AN
INCH OR LESS...MAINLY AT DEN AND LESSER CHANCES AT BJC.
&&
.PREV DISCUSSION... /ISSUED 256 PM MST TUE DEC 31 2013/
SHORT TERM...THERE ARE NORTHWEST WINDS OVER MOST OF THE PLAINS
..WITH SOME GUSTS OVER THE NORTHEAST CORNER UP TO 25 KNOTS.
NEARLY ALL THE CWA EAST OF THE HIGH MOUNTAINS IS NEARLY CLEAR OF
CLOUD COVER. THE CLOUD SHIELD ASSOCIATED WITH THE NEXT STORM IS
JUST UPSTREAM ACCORDING THE CURRENT SATELLITE PICTURES. NEAR IN
THE IMMEDIATE UPSTREAM. MODELS BRING THE APPROACHING TROUGH AXIS
ACROSS THE CWA FROM ABOUT 12Z-18Z WEDNESDAY MORNING. A NORTH-
NORTHWESTERLY ORIENTED JET MAXIMUM IS PROGGED OVER THE CENTRAL CWA
AT 00Z LATE WEDNESDAY AFTERNOON. THE QG VERTICAL VELOCITY FIELDS
SHOW UPWARD MOTION FOR THE CWA THIS EVENING THROUGH WEDNESDAY
MORNING. IT IS PROGGED TO BE PRETTY STRONG AROUND 12Z WEDNESDAY
MORNING. IT IS STRONGER THAN THE LAST TWO DISTURBANCES...LAST
SATURDAY NIGHT AND LAST NIGHT. THE BOUNDARY LAYER FLOW IS PRETTY
DECENT DOWNSLOPE THIS EVENING...WITH A FRONT AND UPSLOPE BEHIND IT
TO MOVE SOUTHWARD FROM 09Z TO 12Z. THE UPSLOPE COVERS THE PLAINS
AND LOWER FOOTHILLS THROUGH 18Z TOMORROW ...WITH DOWNSLOPING
NORTHWESTERLIES AFTER THAT. THERE IS A BIT OF A INVERTED TROUGH
ALONG THE FOOTHILLS/PLAINS INTERFACE. FOR MOISTURE...IS BEST ON
THE GFS...BUT THE NAM AND ECMWF DO HAVE SOME. IT EXISTS QUICKLY
WEDNESDAY AFTERNOON AND THE FOOTHILLS AND IMMEDIATE PLAINS SEEM TO
LACK SOME FROM THE DOWNSLOPING. THE QPF FIELDS HAVE SOME
MEASURABLE SNOWFALL FOR THE MOUNTAINS TONIGHT AND WEDNESDAY...WITH
MINIMAL AMOUNTS OVER THE PLAINS FROM 12Z TO 00Z ON WEDNESDAY. FOR
POPS...WILL STAY THE COURSE FOR THE MOST PART AND KEEP THE
ADVISORIES GOING IN THE HIGH MOUNTAINS OVERNIGHT INTO WEDNESDAY.
FOR THE PLAINS...THE BEST POPS WILL BE OVER THE EASTERN TWO-
THIRDS OF THEM. WILL NOT GO "LIKELY"S OVER THE PLAINS WITH THE LOW
LEVEL WINDS NOT SHOWING DECENT ENOUGH AND LONG ENOUGH UPSLOPE. FOR
TEMPERATURES...WEDNESDAY`S HIGHS ARE 5 TO 10 C COLDER THAN THIS
AFTERNOON`S.
LONG TERM...A PERSISTENT NORTHWEST FLOW PATTERN WILL CONTINUE TO
BRING UNSETTLED WEATHER TO THE REGION. THE SYSTEM ON TUESDAY AND
WEDNESDAY WILL MOVE THROUGH AND WILL BE REPLACED BY SURFACE HIGH
PRESSURE AND RIDGING. TEMPERATURES WILL INCREASE AND BE WARMEST
THURSDAY AND FRIDAY. THE ECMWF BRINGS THE NEXT DISTURBANCE IN JUST
AHEAD OF THE GFS BUT HAS COLD AIR MOVING IN LATER IN THE DAY AND
HAS HIGHER SNOWFALL AMOUNTS OVER MUCH OF THE REGION. THE GFS HAS
PRECIP CENTERED MORE OVER THE MOUNTAINS AND PLAINS WITH THE FRONT
MOVING IN FROM THE EAST AND DOWNSLOPING RIGHT ALONG THE FOOTHILLS
HELPING TO KEEP MUCH OF THE SNOW AWAY FROM THE FRONT RANGE.
HOWEVER, I WOULD NOT COUNT OUT SNOW FOR THE FRONT RANGE FOOTHILLS
AS BANDED PRECIPITATION WILL BE POSSIBLE WITH THE PLACEMENT OF THE
UPPER LEVEL JET THAT COULD COUNTERACT THE DOWNSLOPE FLOW.
CONTINUED JET SUPPORT COMBINED WITH EMBEDDED DISTURBANCES WITHIN
THE FLOW WILL KEEP TEMPERATURES COOLER WITH HIGHS GETTING BACK
INTO THE UPPER 20S AND 40S THROUGH TUESDAY AS WELL AS A SLIGHT
CHANCE OF SNOW OVER THE REGION. INCREASED WINDS WITH THE NORTHWEST
FLOW WILL ALSO BE POSSIBLE ALONG THE NORTHERN MOUNTAINS AND
FOOTHILLS LATER IN THE PERIOD.
AVIATION...NORTHWESTERLIES ARE PRETTY GOOD NOW AT DIA. WE SHOULD
GO TO DRAINAGE SHORTLY AFTER SUNSET...THEN GET A BIT OF WESTERLY
COMPONENT TO THEM AFTER 05Z. WILL BRING UPSLOPE WIND SHIFT IN
ABOUT 11Z. CEILING WILL BECOME AN ISSUE BY 12Z. THEY COULD GET AS
LOW AS 1000 AGL. SNOW ONLY IN PROB30 GROUP NOW...BUT PERHAPS A
TEMPO GROUP WILL BE NEEDED. WOULD NOT PUT IT IN THE PREDOMINANT
PERIOD OF THE TAF AT THIS TIME.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO NOON MST
WEDNESDAY FOR COZ033-034.
WINTER WEATHER ADVISORY UNTIL NOON MST WEDNESDAY FOR COZ031.
&&
$$
SHORT TERM...ENTREKIN
LONG TERM....BOWEN
AVIATION...ENTREKIN
AREA FORECAST DISCUSSION
NWS ALBANY NY
433 AM EST WED JAN 1 2014
.SYNOPSIS...
AN APPROACHING STORM SYSTEM TODAY WILL REFORM OFF THE
EASTERN SEABOARD ON THURSDAY...ALLOWING FOR A PROLONGED PERIOD OF
SNOW ACROSS THE REGION FOR TONIGHT THROUGH FRIDAY MORNING. VERY COLD
AIR WILL ACCOMPANY THIS SNOW...ESPECIALLY ACROSS NORTHERN AND HIGH
TERRAIN PORTIONS OF THE REGION. DRY...BUT CONTINUED COLD WEATHER
WILL BE IN PLACE ON SATURDAY...BEFORE ANOTHER STORM THREATENS THE
REGION FOR SUNDAY INTO MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 430 AM EST...WITH HIGH PRESSURE SITUATED SOUTH OF THE AREA
OVER THE MID ATLANTIC STATES...SKIES ARE MAINLY CLEAR OVER THE
REGION THIS MORNING...ALONG WITH COLD TEMPERATURES. A BAND OF LAKE
EFFECT SNOW CONTINUES OFF LAKE ONTARIO...ALTHOUGH THE BULK OF THIS
ACTIVITY IS OCCURRING WELL WEST OF OUR AREA. SOME STRATOCU CLOUDS
FROM THIS LAKE EFFECT ACTIVITY ARE OVER WESTERN PARTS OF THE
AREA...ALONG WITH SOME LIGHT SNOW SHOWERS AND FLURRIES ACROSS
HERKIMER COUNTY. THE LATEST 07Z HRRR SHOWS LAKE EFFECT ACTIVITY TO
DIMINISH OVER THE NEXT FEW HOURS AS INVERSION HEIGHTS SLOWLY
LOWER...SO LITTLE ADDITIONAL LAKE EFFECT SNOWFALL IS EXPECTED TO
ACCUMULATE OVER HERKIMER COUNTY THIS MORNING.
AN UPPER LEVEL TROUGH WILL CONTINUE TO SHARPEN OVER THE
CENTRAL PLAINS TODAY AS IT MOVES EASTWARD TOWARDS THE OHIO
VALLEY. SURFACE LOW PRESSURE WILL START TO DEVELOP OVER THE
MISSISSIPPI VALLEY AND A SURFACE BOUNDARY WILL EXTEND ACROSS THE
OHIO VALLEY TOWARDS WESTERN PA.
BROAD SW FLOW OVER THIS FRONTAL BOUNDARY WILL ALLOW FOR
OVERRUNNING SNOWFALL TO DEVELOP ACROSS WESTERN AND CENTRAL NY TODAY.
MOST OF THE DAY LOOKS DRY ACROSS OUR REGION...BUT THIS SNOW WILL
START TO SPREAD TOWARDS OUR WESTERN ZONES BY LATE THIS AFTN AND
EARLY THIS EVENING. AS A RESULT...CLOUDS WILL INCREASE TODAY FROM
WEST TO EAST. WHILE THE DAY WILL START OFF WITH A GOOD DEAL OF
SUNSHINE...SKIES WILL BE MOSTLY CLOUDY BY THIS AFTN.
MAX TEMPS WILL RANGE FROM THE TEENS OVER THE ADIRONDACKS TO THE
20S ACROSS THE REMAINDER OF THE AREA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
WINTER STORM WATCHES HAVE BEEN ISSUED FOR THE ENTIRE AREA OUTSIDE
THE ADIRONDACKS/LAKE GEORGE/SARATOGA AREAS...FOR TONIGHT THROUGH
FRIDAY MORNING.
...A PROLONGED PERIOD OF SNOWFALL ACROSS OUR REGION WILL ALLOW FOR A
MODERATE TO HEAVY SNOWFALL FOR MUCH OF THE AREA...
WITH THE SURFACE BOUNDARY SITUATED SOUTH OF THE AREA...ISENTROPIC
LIFT/WARM AIR ADVECTION WILL ALLOW FOR LIGHT SNOW TONIGHT INTO
THURSDAY. AT THE SAME TIME...AN AREA OF SURFACE LOW PRESSURE WILL
DEVELOP OFF THE EASTERN SEABOARD ON THURSDAY...AND MOVE NORTHEAST
FOR THURSDAY NIGHT. THIS STORM WILL BE FAIRLY FAR OFF THE
COAST...BUT SHOULD STILL ALLOW FOR SOME ATLANTIC MOISTURE TO GET
THROWN BACK INTO OUR AREA. WITH THE STRONG UPPER TROUGH MOVING
TOWARDS OUR AREA FOR THURSDAY NIGHT...DEFORMATION WILL ALLOW FOR
ADDITIONAL SNOWFALL...BEFORE SNOWFALL TAPERS OFF EARLY FRIDAY
MORNING. SOME BANDING OF SNOWFALL COULD OCCUR ACROSS FAR EASTERN
PARTS OF OUR AREA THURSDAY NIGHT AS THE LOW PRESSURE STARTS TO
RAPIDLY DEEPEN. WHILE SNOW RATES AREN/T EXPECTED TO BE EXTREME AT
ANY POINT DURING THIS STORM...THE PROLONGED NATURE OF THE EVENT
WILL ALLOW FOR A SIGNIFICANT IMPACT ACROSS OUR AREA.
SNOW TO LIQUID RATIOS WILL BE VERY HIGH...GENERALLY 15:1 OR
HIGHER...AS STRONG OMEGA WILL BE MOVING THROUGH THE DENDRITIC
GROWTH ZONES /WHICH WILL BE VERY LOW TO THE GROUND DUE TO THE COLD
TEMPS IN PLACE/. THIS WILL ALLOW FOR A LIGHT AND FLUFFY SNOW TO
ADDS UP VERY EASILY TO OCCUR.
THE MAIN FORECAST QUESTION IS HOW MUCH QPF OCCURS. THE 00Z AND 06Z
NAM HAVE BEEN PERSISTENT IN SHOWING MUCH MORE QPF THAN THE OTHER
MODELS...WITH OVER 1.00 INCH LIQUID OVER CENTRAL/SOUTHERN PORTIONS OF
THE AREA. MEANWHILE..THE 00Z GFS/ECMWF/GGEM AND GEFS MEAN ARE
SHOWING AROUND 0.60 INCHES ACROSS MUCH OF THE AREA GIVE OR TAKE. THE
03Z SREF MEAN FOR KALB IS 0.84 INCHES. WE WILL KEEP THE FORECAST CLOSE
TO MODEL CONSENSUS FOR NOW...BUT CONTINUE TO MONITOR MODEL
TRENDS...AS THE NAM CAN SOMETIMES PICK UP ON MESOSCALE ASPECTS
THAT THE GLOBAL MODELS DO NOT. EVEN WITH THESE LESSER AMOUNTS...IT
STILL LOOKS LIKE WE WILL REACH WINTER STORM WARNING CRITERIA /9
INCHES IN 24 HOURS/ ACROSS CENTRAL/SOUTHERN AREAS DUE TO THE
EXPECTED HIGH RATIOS...WHICH IS WHY THE WATCH HAS BEEN ISSUED FOR
THESE AREAS. FURTHER NORTH ACROSS THE ADKS/LAKE GEORGE/SARATOGA
AREA...SNOWFALL AMOUNTS WILL BE SLIGHTLY LESS...BUT A PLOWABLE
SNOW IS STILL EXPECTED.
TEMPS WILL BE QUITE COLD DURING THE ENTIRE EVENT. AFTER TEMPS
REACH THE THEIR HIGH ON WEDNESDAY...THEY WILL BASICALLY HOLD
STEADY/SLOWLY FALL FOR WED NIGHT THROUGH THURSDAY INTO THURSDAY
NIGHT. TEMPS WILL BE IN THE TEENS TONIGHT/THURSDAY...AND FALL INTO
THE SINGLE DIGITS TO SINGLE DIGITS BELOW ZERO FOR THURSDAY NIGHT.
OVER THE ADIRONDACKS...TEMPS WILL FALL ZERO TO MINUS 20 FOR
THURSDAY NIGHT. WITH A N-NE WIND IN PLACE...THIS WILL ALLOW FOR VERY
COLD WIND CHILL VALUES OVER THE ADIRONDACKS. A WIND CHILL WATCH
HAS BEEN ISSUED FOR THE POTENTIAL FOR WIND CHILL VALUES OF -30 TO
-40 BELOW ZERO FOR LATE THURSDAY NIGHT INTO FRIDAY MORNING.
ELSEWHERE...WIND CHILL VALUES MAY REACH ADVISORY CRITERIA..AND
THIS WILL BE HIGHLIGHTED IN THE HWO.
ANY LINGERING SNOW SHOWERS WILL BE TAPERING OFF FRIDAY
MORNING...AND SKIES LOOK TO BECOME MOSTLY SUNNY BY FRI AFTN.
DESPITE THE RETURN OF THE SUN...IT WON/T DO ANYTHING FOR
TEMPS...WITH DAYTIME HIGHS ONLY IN THE SINGLE DIGITS. SOME AREAS
IN THE ADIRONDACKS AND UPPER MOHAWK VALLEY MAY NOT EVEN REACH ZERO
FOR HIGHS ON FRIDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
ANOTHER STORM SYSTEM FOR SUNDAY NIGHT INTO MONDAY.
WE WILL START OUT THE PERIOD WITH RIDGING BUILDING IN ALOFT WITH THE
SURFACE HIGH CRESTING OVER THE REGION LATE FRIDAY NIGHT INTO
SATURDAY MORNING. ALONG WITH A FRESH SNOW THIS WILL SET THE STAGE
FOR ANOTHER COLD NIGHT ACROSS THE REGION WITH LOWS EXPECTED TO BE
BELOW ZERO ACROSS THE ENTIRE FORECAST AREA.
THE SURFACE HIGH IS EXPECTED TO SHIFT EASTWARD OFF THE COAST
SATURDAY. DESPITE A SOUTHERLY FLOW DEVELOP IT WILL BE COLD WITH
THE FRESH SNOWPACK ON THE GROUND WITH HIGHS ONLY IN THE TEENS.
BROAD SOUTHWESTERLY FLOW WILL DEVELOP ACROSS THE EASTERN UNITED
STATES AS A POTENT SHORT WAVE MOVES INTO OVER PACIFIC NORTHWEST
DIGGING A DEEP TROUGH OVER THE CENTRAL CONUS OVER THE WEEKEND. IN
ADDITION...AN UPPER LEVEL LOW WILL STRENGTHEN AS IT MOVES SOUTHWARD
ACROSS CENTRAL CANADA TOWARDS THE GREAT LAKES REGION. PIECES OF
ENERGY ARE EXPECTED TO ROTATE ABOUT THIS LOW AS IT MOVES EASTWARD
ACROSS EASTERN CANADA AS WE HEAD INTO NEXT WEEK.
THERE IS GOOD AGREEMENT AMONGST THE MODEL GUIDANCE THAT THE LOW
PRESSURE SYSTEM ASSOCIATED WITH THE UPPER LOW WILL REMAIN WELL TO
OUR NORTHWEST. HOWEVER THERE ARE DIFFERENCES AND THE FORECAST GETS
COMPLICATED AS THE POTENT SHORT WAVE ROTATES THROUGH THE BASE OF THE
DEEP TROUGH OVER THE TENNESSEE VALLEY AND SPINNING UP A SURFACE LOW.
THE ECMWF CONTINUES TO DEVELOP AND TRACK THE LOW FARTHER TO THE WEST
PASSING THE LOW OVER THE OHIO VALLEY DUE TO THE POSITION OF THE
UPPER LOW BEING FARTHER TO WEST. WHILE THE GFS BRINGS THE LOW ACROSS
NEW YORK AND NEW ENGLAND SUNDAY NIGHT INTO MONDAY. THE OPERATIONAL
GFS IS ON THE WEST SIDE OF THE GFSENSEMBLE TRACKS. THE EXACT TRACK
OF THE LOW WILL DETERMINE THE THERMAL PROFILE AND THEREFORE P-TYPES.
HAVE USED GUIDANCE FROM THE WEATHER PREDICTION CENTER WHICH TOOK A
COMPROMISE TRACK THEN LEANED TOWARD THE GFS THE COLDER SCENARIO.
BASED ON THIS HAVE FORECASTED PRECIPITATION TO OVERSPREAD THE AREA
SUNDAY NIGHT THEN CONTINUE INTO MONDAY. WOULD EXPECT SNOW SUNDAY
NIGHT WITH A CHANGEOVER TO RAIN LIKELY ACROSS THE HUDSON VALLEY AND
LITCHFIELD ON MONDAY WITH RAIN POSSIBLE FARTHER NORTHWARD.
UNCERTAINTY IS THIS FORECAST IS HIGH AT THIS TIME.
FOLLOWING THIS STORM SYSTEM ANOTHER ROUND OF VERY COLD ARCTIC AIR IS
EXPECTED WITH DAYTIME HIGHS SIMILAR TO WHAT OUR NORMAL LOWS SHOULD
BE.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS ARE EXPECTED FOR MUCH OF THE TAF PERIOD WITH MVFR
CONDITIONS DEVELOPING BY 04Z-06Z/THURSDAY. SCATTERED LAKE EFFECT
CLOUDS ARE EXPECTED TO IMPACT THE TAFS THROUGH MUCH OF THE EARLY
MORNING HOURS. HIGH LEVEL CIRRUS CLOUDS IN ADVANCE OF A COMPLEX
STORM SYSTEM WILL BEGIN TO STREAM INTO THE REGION AFTER SUNRISE WITH
MID LEVEL CLOUDS FOLLOWING CLOSE BEHIND. CLOUDS WILL LOWER AND
THICKEN WITH LIGHT OVERRUNNING SNOW EXPECTED TO START BY LATE IN
THE EVENING.
SOUTHWEST TO WEST SURFACE WINDS AT GENERALLY LESS THAN 10 KNOTS
OVERNIGHT EXCEPT AT KPSF WHERE THEY WILL BE A BIT STRONGER WITH
GUSTS CONTINUING INTO THE EARLY MORNING HOURS. WIND WILL BE MORE
WESTERLY WEDNESDAY AND PICK UP IN SPEED A BIT WITH GUSTS EXPECTED AT
KALB AND KPSF. BY LATE AFTERNOON INTO THE EVENING WINDS WILL WEAKEN
AND SHIFT TOWARD THE NORTH.
OUTLOOK...
THU NIGHT: HIGH OPERATIONAL IMPACT. DEFINITE SN.
FRI: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
FRI NIGHT-SAT NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUN: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
&&
.HYDROLOGY...
NO WIDESPREAD HYDROLOGIC PROBLEMS ARE EXPECTED OVER THE NEXT FIVE DAYS.
A STORM SYSTEM WILL BRING SNOW TO THE REGION TONIGHT THROUGH
FRIDAY MORNING. VERY COLD TEMPERATURES ARE EXPECTED LATE THIS
WEEK...WHICH WILL CONTINUE TO ALLOW RIVER AND LAKE ICE TO FORM AND
THICKEN.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WINTER STORM WATCH FROM THIS EVENING THROUGH FRIDAY MORNING
FOR CTZ001-013.
NY...WINTER STORM WATCH FROM THIS EVENING THROUGH FRIDAY MORNING
FOR NYZ038>040-047>054-058>061-063>066.
WIND CHILL WATCH FROM THURSDAY EVENING THROUGH FRIDAY MORNING
FOR NYZ032-033-042.
MA...WINTER STORM WATCH FROM THIS EVENING THROUGH FRIDAY MORNING
FOR MAZ001-025.
VT...WINTER STORM WATCH FROM THIS EVENING THROUGH FRIDAY MORNING
FOR VTZ013>015.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS
SHORT TERM...FRUGIS
LONG TERM...IAA
AVIATION...IAA
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS ALBANY NY
1251 AM EST WED JAN 1 2014
.SYNOPSIS...
AS ARCTIC HIGH PRESSURE BUILDS INTO THE REGION
OVERNIGHT...EXPECT MAINLY DRY BUT COLD CONDITIONS ACROSS THE REGION
THROUGH NEW YEARS DAY. THE EXCEPTION WILL BE HEAVY LAKE EFFECT SNOW
SQUALLS WHICH WILL OCCUR TO THE EAST AND SOUTHEAST OF LAKE ONTARIO.
A POTENT MID LEVEL DISTURBANCE WILL COMBINE WITH ATLANTIC MOISTURE
TO BRING A PROLONGED PERIOD OF LIGHT TO MODERATE SNOW TO THE REGION
LATE WEDNESDAY NIGHT THROUGH EARLY FRIDAY. BITTER COLD ARCTIC AIR
WILL FOLLOW TO CLOSE OUT THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1251 AM EST...LAKE EFFECT SNOW OFF LAKE ONTARIO HAS WEAKENED
SOMEWHAT...BUT IS STILL IMPACTING THE WESTERN ADIRONDACKS. KTYX
RADAR SHOWS THE HEAVIEST SNOWFALL IS NOW WEST OF THE AREA OVER THE
TUG HILL PLATEAU. THE LATEST 03Z 3KM HRRR SHOWS THIS BAND SLOWLY
DRIFTING SOUTH OVER THE NEXT FEW HOURS...WITH THE HEAVIEST ECHOES
REMAINING WEST OF THE REGION AND CLOSER TO THE LAKE SHORE.
STILL...SINCE SOME SNOW WILL CONTINUE TO IMPACT THE WESTERN
ADIRONDACKS /ESP NORTHERN HERKIMER COUNTY AROUND THE OLD FORGE
AREA/ OVERNIGHT WE WILL KEEP THE CURRENT LAKE EFFECT HEADLINES IN
PLACE...BUT THEY MAY NOT BE NEEDED UNTIL THEIR CURRENT EXPIRATION
TIME OF 10 AM THIS MORNING. SNOW AMOUNTS WILL BE HIGHLY VARIABLE
DEPENDING ON HOW LONG THE BAND SITS OVER ONE LOCATION...BUT
LOCALIZED LAKE EFFECT STORM TOTAL SNOW AMOUNTS OF 7 TO 10 INCHES
LOOKS TO OCCUR SOMEWHERE NEAR THE OLD FORGE/INLET AREA.
ELSEWHERE...THERE IS A FAIRLY QUIET START TO 2014 WITH MAINLY
CLEAR SKIES...DRY CONDITIONS AND COLD TEMPERATURES. TEMPS ARE
CURRENTLY IN THE MID TEENS TO LOW 20S OVER THE VALLEY AREAS...AND
OVERNIGHT LOWS LOOK TO RANGE FROM NEAR ZERO IN THE ADIRONDACKS TO
THE LOW TO MID TEENS ACROSS THE REMAINDER OF THE AREA.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/...
THE LAKE EFFECT BAND OF LAKE ONTARIO WILL LINGER INTO THE EARLY
PORTION OF WEDNESDAY BEFORE IT FINALLY FALLS APART. AFTER
THAT...NEW YEAR`S DAY WILL START OFF DRY ACROSS THE REGION WITH
PERHAPS A LITTLE MORNING SUNSHINE.
HOWEVER...ANY SUNSHINE WILL BE SHORT LIVED. SHORT WAVE ENERGY
OVER THE PACIFIC NORTHWEST WILL DIG A TROUGH OVER THE PLAINS AND
THIS WILL BRING US OUR NEXT SNOW STORM BY THURSDAY. CLOUDS FROM THIS
DEVELOPING SYSTEM...WHICH INCLUDES MOISTURE OFF THE ATLANTIC AS WELL
AS INCREASING ISENTROPIC LIFT...WILL THICKEN LATE IN THE DAY. SOME
LIGHT SNOW OR FLURRIES COULD BREAK OUT BEFORE THE END OF THE DAY
WEDNESDAY. THE BEST CHANCE OF THIS HAPPENING WOULD BE ACROSS THE
CATSKILLS BUT OVERALL...MOST PLACES SHOULD REMAIN DRY THROUGH NEW
YEAR`S DAY. LOOK FOR HIGHS MAINLY IN THE 20S...LOWER 20S LOCALLY IN
THE CAPITAL REGION...BUT ONLY TEENS ACROSS THE ADIRONDACKS.
AN STEADY OVERRUNNING SNOW...MAINLY LIGHT...IS EXPECTED TO DEVELOP
AT NIGHT ESPECIALLY LATE WELL IN ADVANCE OF AN APPROACHING WARM
FRONT. ALOFT...IT LOOKS AS A FRONTOGENESIS BAND WILL SET UP OVER OUR
REGION WHICH WILL SERVE AS EXCELLENT CONVERGENCE/COLD CONVEYOR BELT
FOR ATLANTIC MOISTURE TO OVERRUN. THE SNOW COULD BE MODERATE AT
TIMES (ABOUT HALF AN INCH PER HOUR) BUT MUCH OF TIME THE SNOWFALL
RATE COULD BE A LITTLE LESS. THE SNOW TO LIQUID RATIO LOOKS TO BE A
A LITTLE HIGHER THAN THE CLIMATOLOGICAL NORMAL OF 13:1...PROBABLY
CLOSER TO 20:1. GIVEN THAT SNOW LOOKS TO FALL THROUGH
THURSDAY...TAPERING TO SNOW SHOWERS OR FLURRIES BY FRIDAY
MORNING...WE ARE LOOKING FOR A GENERAL 6-12 INCHES OF
SNOWFALL...WITH LOCALLY HIGHER AMOUNTS POSSIBLE ACROSS THE
CATSKILLS).
IT WILL BE VERY COLD WHEN IT IS SNOWING...WITH TEMPERATURES MAINLY
IN THE TEENS (AND EVEN SINGLE NUMBERS UP NORTH). THIS WILL MAKE IT
HARD FOR TREATED ROADS TO STAY WET. IT WILL ALSO INCREASE OF
RISK FROST BITE FOR THOSE NOT PROPERLY DRESSED TO REMOVE SNOW...OR
HAVING TO WALK FOR EXTENDED PERIODS OUTSIDE.
THE SNOW LOOKS TO FINALLY MOVE OUT ON FRIDAY. BY FRIDAY...ENERGY
FROM THIS SYSTEM LOOKS TO PHASE WITH AN OCEAN STORM WELL TO THE
SOUTH AND EAST OF OUR REGION. THIS STORM ORIGINALLY LOOKED TO BRING
MORE SNOW ON FRIDAY. HOWEVER...THAT THREAT IS NOW GONE.
WHAT IS NOT GONE HOWEVER...IS BITTERLY COLD AIR THAT WILL FOLLOW IN
THE WAY OF DISTURBANCE. THE OCEAN STORM...DESPITE BEING WELL
OFFSHORE...WILL HELP PINWHEEL AIR COLDER THAN -20C OVER OUR REGION
BY FRIDAY AFTERNOON ALONG WITH A BREEZE. HIGH TEMPERATURES ON FRIDAY
LOOK TO STAY IN THE SINGLE NUMBERS FROM THE CAPITAL REGION
NORTHWARD...TEENS SOUTH. IN FACT...MANY FOLKS ACROSS THE ADIRONDACKS
WILL REMAIN BELOW ZERO ALL DAY LONG. THE COMBINATION OF THESE
TEMPERATURES ALONG WITH A 10 TO 20 MPH NORTHWEST WIND WILL PRODUCE
POTENTIAL DANGEROUS WIND CHILLS IN THE -15 TO -25 RANGE...ONLY TO
GET EVEN LOWER FRIDAY NIGHT.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
WITH THE SYSTEM DEPARTING EARLY ON FRIDAY...EXPECT THE ARCTIC HIGH
PRESSURE SYSTEM TO CREST OVER THE REGION FRIDAY NIGHT. WITH FRESH
SNOW COVER...LIGHT WINDS AND MAINLY CLEAR SKIES EXPECT TEMPS TO
PLUMMET WITH LOWS FORECAST TO DROP TO BETWEEN 5 BELOW AND 20 BELOW
ZERO...WITH SOME PLACES IN THE ADIRONDACKS DROPPING TO AS LOW AS 25
BELOW ZERO.
THE HIGH WILL QUICKLY MOVE OFFSHORE ON SATURDAY AND A SOUTHERLY FLOW
WILL TAKE HOLD ACROSS THE REGION. ALTHOUGH TEMPS WILL RECOVER BY AS
MUCH AS 30 TO 40 DEGREES ON SATURDAY...IT WILL STILL BE COLD WITH
HIGHS ONLY IN THE MID TEENS TO LOWER 20S.
FAIR WEATHER WILL CONTINUE INTO SATURDAY NIGHT...BUT WITH A LIGHT
SOUTHERLY FLOW ACROSS THE REGION...IT WILL NOT BE NEARLY AS COLD
WITH LOWS BETWEEN 5 AND 15 DEGREES ABOVE ZERO.
FOR SUNDAY THROUGH MONDAY THERE IS A BIG DISCREPANCY REGARDING THE
NEXT STRONG LOW PRESSURE SYSTEM THAT WILL AFFECT THE REGION. ECMWF
HAS THE LOW TRACKING WELL TO THE WEST OF THE ALBANY FORECAST
AREA...WHILE THE GFS TRACKS THE LOW THROUGH SOUTHEAST NY. THE
RESULTANT WEATHER WOULD BE MAINLY RAIN BASED ON THE ECMWF...WITH
MAINLY SNOW OR MIXED PCPN WITH THE GFS. FOR NOW HAVE FAVORED A
COLDER SOLUTION...BUT MILD ENOUGH FOR A CHANGEOVER TO RAIN AT SOME
POINT OVER THE SOUTHEAST ZONES. HIGHS SUNDAY WILL BE IN THE UPPER
20S TO MID 30S. LOWS SUNDAY NIGHT IN THE 20S...HIGHS MONDAY IN THE
30S.
AFTER THE STORM GOES BY...BOTH THE GFS AND ECMWF BRING ANOTHER SURGE
OF COLD ARCTIC AIR INTO THE REGION. LOWS MONDAY NIGHT WILL BE 5 TO
15 ABOVE...WITH HIGHS TUESDAY ONLY IN THE MID TEENS TO LOWER 20S.
FRIGID TUESDAY NIGHT WITH LOWS BETWEEN 5 ABOVE AND 10 BELOW ZERO.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS ARE EXPECTED FOR MUCH OF THE TAF PERIOD WITH MVFR
CONDITIONS DEVELOPING BY 04Z-06Z/THURSDAY. SCATTERED LAKE EFFECT
CLOUDS ARE EXPECTED TO IMPACT THE TAFS THROUGH MUCH OF THE EARLY
MORNING HOURS. HIGH LEVEL CIRRUS CLOUDS IN ADVANCE OF A COMPLEX
STORM SYSTEM WILL BEGIN TO STREAM INTO THE REGION AFTER SUNRISE WITH
MID LEVEL CLOUDS FOLLOWING CLOSE BEHIND. CLOUDS WILL LOWER AND
THICKEN WITH LIGHT OVERRUNNING SNOW EXPECTED TO START BY LATE IN
THE EVENING.
SOUTHWEST TO WEST SURFACE WINDS AT GENERALLY LESS THAN 10 KNOTS
OVERNIGHT EXCEPT AT KPSF WHERE THEY WILL BE A BIT STRONGER WITH
GUSTS CONTINUING INTO THE EARLY MORNING HOURS. WIND WILL BE MORE
WESTERLY WEDNESDAY AND PICK UP IN SPEED A BIT WITH GUSTS EXPECTED AT
KALB AND KPSF. BY LATE AFTERNOON INTO THE EVENING WINDS WILL WEAKEN
AND SHIFT TOWARD THE NORTH.
OUTLOOK...
THU NIGHT: HIGH OPERATIONAL IMPACT. PDS SN.
FRI: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
FRI NIGHT-SAT NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUN: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED THIS WEEK. THE WEATHER
PATTERN WILL BE ACTIVE WITH PRECIPITATION EXPECTED TO BE IN THE FORM
OF SNOW. IT WILL BE VERY COLDER SO ICE FORMATION AND THICKENING WILL
OCCUR.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...LAKE EFFECT SNOW WARNING UNTIL 10 AM EST THIS MORNING FOR
NYZ032-033.
LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST THIS MORNING FOR
NYZ038.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS/HWJIV
NEAR TERM...FRUGIS
SHORT TERM...HWJIV
LONG TERM...GJM
AVIATION...IAA
HYDROLOGY...IAA/HWJIV
AREA FORECAST DISCUSSION...UPDATED
NWS MELBOURNE FL
418 AM EST WED JAN 1 2014
.DISCUSSION...
TODAY-TONIGHT...
LATEST SURFACE ANALYSIS SHOWS THAT A COASTAL TROUGH HAS ALREADY
SET UP AND WAS EVEN INLAND A LITTLE IN THE SOUTH. AS HIGH PRESSURE
TO THE NORTH PUSHES SEAWARD...A MORE SOUTHERLY WIND COMPONENT WILL
CAUSE THE TROUGH/WARM FRONT TO SHIFT NORTH OF THE AREA TONIGHT.
ISENTROPIC LIFT WAS ALREADY EVIDENT WITH PRECIP ALOFT STREAMING
ACROSS THE NORTH HALF OF THE AREA. A LOW LEVEL DRY LAYER WAS
INHIBITING MUCH RAIN AT THE SURFACE...BUT AS ISENTROP LIFT
CONTINUES TODAY THERE SHOULD BE A GOOD COVERAGE OF RAINFALL
BREAKING OUT ACROSS THE NORTH HALF.
THE 00Z GFS ALSO INDICATED AN AREA OF SHOWERS DEVELOPING NEAR THE
INVERTED TROUGH ALONG THE SPACE/TREASURE COAST THIS AFTERNOON.
SOME LOCAL HEAVY RAINFALL IS POSSIBLE WHERE LOW LEVEL CONVERGENCE
IS MAXIMIZED. MOS POPS TODAY RANGE FROM AROUND 60 PERCENT IN THE
SOUTH TO OVER 80 IN THE NORTH. HAVE ONLY MADE MINOR ADJUSTMENTS TO
THOSE VALUES.
WEAK LOW PRESSURE MOVING ALONG THE BOUNDARY IN THE GULF OF MEXICO
TONIGHT WILL INCREASE SOUTHERLY FLOW AND SHIFT THE WARM FRONT
NORTH OF THE AREA. POPS SHOULD STAY HIGH IN THE NORTH ESPECIALLY
FOR THE EARLY HALF OF THE NIGHT AND HAVE CONTINUED PREVIOUS
FORECAST FOR LIKELY POPS THERE. SOUTHERN SECTIONS WILL GET FULLY
INTO THE WARM SECTOR AND FORECAST SOUNDINGS SHOW DRYING ALOFT BUT
CANNOT RULE OUT A CHANCE OF SHOWERS IN MOIST SOUTHERLY LOW LEVEL
FLOW.
MOSTLY CLOUDY SKIES AND RAIN COOLING WILL CAUSE TEMPS TO STRUGGLE
TO REACH 70 IN THE NORTH. SOUTHERN AREAS MAY EXPERIENCE SOME BRIEF
SOLAR INSOLATION AND ALLOW TEMPS TO BRIEFLY REACH TO AROUND 80
DEGREES. MILD SOUTH FLOW TONIGHT WILL KEEP MINS IN THE 60S AND
POSSIBLY BE AROUND 70 IN THE FAR SOUTH.
THU-THU NIGHT...
AIDED BY A STRONG CONFLUENT H85-H30 FLOW OVER THE ERN CONUS...A
BROAD AREA OF LOW PRES OVER THE HIGH PLAINS WILL RACE INTO THE MID
ATLC BY DAYBREAK THU...THEN UP THE ERN SEABOARD AND INTO THE NW
ATLC. THIS SYSTEM WILL DRAG THE NEXT COLD FRONT THRU CENTRAL FL THRU
THE DAY...PROVIDING A RESPECTABLE CHANCE FOR PRECIP.
CURRENT AIRMASS WILL REQUIRE SOME TIME TO MODIFY AS THE KTBW/KXMR
SOUNDINGS SHOW A SUBSTANTIAL AMOUNT OF DRY AIR THRU THE H100-H70
LYR. DEEPER MOISTURE LURKS TO THE S AND SW...HOWEVER. THE KMFL
SOUNDING SHOWS THE AIRMASS OVER S FL NEARLY SATURATED THRU THE
H100-H60 LYR WHILE THE RUC ANALYSIS SHOWS H100-H70 MEAN RH VALUES
OVER 90PCT BLANKETING THE WRN GOMEX.
A STRONG SRLY FLOW WILL DVLP AHEAD OF THE FRONT THAT WILL GRADUALLY
VEER TO THE SW THRU THE DAY AS THE FRONTAL TROF PLOWS INTO A
MODERATELY STRONG HI PRES RIDGE OVER SW ATLC. THE RESULTING WARM AIR
ADVECTION PATTERN WILL PUSH MAX TEMPS INTO THE U70S/M80S...ABOUT
10-15F ABV AVG...DESPITE EXTENSIVE CLOUD COVER. THIS SHOULD PROVIDE
SUFFICIENT SFC LIFT TO KEEP THUNDER MENTIONED IN THE FCST.
HOWEVER...STRONG/SVR WX APPEARS UNLIKELY AS THE SE CONUS IS
DOMINATED BY A STRONG LIFTING H30-H20 JET THAT WILL PULL THE
MERIDIONAL JET DIGGING OUT OF WRN CANADA TO THE E...KEEPING ITS
ENERGY WELL N OF THE FL PENINSULA.
STRONG COLD AIR ADVECTION WILL DEVELOP OVERNIGHT AS WINDS VEER TO
THE NW BEHIND THE FRONT. GFS/ECMWF BOTH INDICATE THE 560DM THICKNESS
LINE PUSHING S OF THE I-4 CORRIDOR IN THE EARLY MORNING HRS...AND
BOTH MOS OUTPUTS DROP TEMPS INTO THE L/M40S NW OF I-4...M/U50S SPACE
AND TREASURE COASTS. THIS WOULD REPRESENT A 24HR TEMP SWING BTWN
25-30F.
FRI-FRI NIGHT...
STRONG POST FRONTAL HI PRES RIDGE WILL PUSH A DRY/STABLE ACRS
CENTRAL FL. DESPITE MSUNNY SKIES...A DEEP N/NWRLY FLOW WILL GENERATE
A COLD AIR ADVECTION PATTERN THAT WILL KEEP MAX TEMPS A SOLID 10-15F
BLO AVG...L/M50S N OF I-4 AND L/M60S ALONG THE COAST. THE COOL AIR
WILL BEGIN TO MODIFY FRI NIGHT AS WINDS VEER TO THE NE AND BEGIN TO
PUSH WARM OCEAN AIR BACK ONSHORE...MIN TEMPS IN THE M/U40S OVER THE
INTERIOR WILL BE NEAR AVG...M/U50S ALONG THE SPACE AND TREASURE
COASTS WILL BE SLIGHTLY ABV AVG.
SAT-MON...
PROGRESSIVE WX PATTERN WILL CONTINUE INTO THE WEEKEND AS THE SRN
BRANCH OF THE JET STREAM HOLDS ON TO A STRONG ZONAL COMPONENT. POST
FRONTAL RIDGE WILL PUSH INTO THE W ATLC ON SAT AND GRADAULLY
WEAKEN...ALLOWING WINDS TO VEER TO THE E ON SAT...THEN TO THE SE ON
SUN. WX PATTERN SHOULD REMAIN DRY THRU THE DAY ON SAT AS THE ONSHORE
FLOW STEADILY MODIFIES THE DRY AIR...BUT WILL NEED TO REINTRODUCE
POPS BACK TO THE FCST SAT NIGHT AS WINDS VEER TO THE SE...PUSHING
THE REMNANT FRONTAL BOUNDARY OVER THE FL STRAITS BACK TO THE N AS A
WARM FRONT.
PRECIP CHANCES WILL CONTINUE INTO EARLY NEXT WEEK AS THE WARM FRONT
STALLS ACRS CENTRAL FL AHEAD OF A NEW COLD FRONT FCST TO PUSH INTO
THE DEEP SOUTH ON SUN...THEN THRU CENTRAL FL ON MON. DESPITE
INCREASED CLOUD COVER AND PRECIP...THE WARM S/SERLY FLOW WILL PUSH
TEMPS BACK UP ABV AVG TO START THE WEEK. MINS IN THE M50S/L60S
INTERIOR...L/M60S ALONG THE COAST. MAX TEMPS IN THE U70S/M80S ON
SUN...DROPPING BACK INTO THE 70S AREAWIDE ON MON AS THE FRONT
APPROACHES.
ECMWF CONTINUES TO ADVERTISE THE COLDEST AIRMASS OF THE SEASON
PUSHING INTO CENTRAL FL BEHIND THIS NEW FRONT WITH PORTIONS OF THE
INTERIOR N OF I-4 DROPPING INTO THE M30S...M/U40S TREASURE COAST.
GFS MOS IS 5-10F WARMER ACRS THE BOARD WITH MINS NEAR CLIMO AVG.
HOWEVER...THE 01/00Z GFS RUN DID TREND IN THE DIRECTION OF THE
ECMWF...IF ONLY BY A FEW DEGS. STAY TUNED...
&&
.AVIATION...
DETERIORATING CONDITIONS WILL OCCUR TODAY AS WARM FRONT LIFTS
SLOWLY UP THE PENINSULA. THIS WILL CAUSE AREAS OF RAIN WITH LOW
MVFR CEILINGS DEVELOPING BY AFTERNOON...ESPECIALLY KISM-KMCO-KTIX
NORTHWARD. MOS HAS CEILINGS THERE A LITTLE BELOW 1000 FEET THIS
AFTERNOON AND BELOW 500 FEET TONIGHT. ITS NOT OUT OF THE QUESTION
TO HAVE LOW LEVEL WIND SHEAR THERE TOO OVERNIGHT. WITH AN INVERTED
TROUGH/WARM FRONT NEAR THE KMLB-KSUA CORRIDOR...THE PRECIP MAY BE
A LITTLE MORE CONVECTIVE IN NATURE BUT STILL EXPECT MVFR CEILINGS
WITH A CHANCE THEY COULD BE AS LOW AS FL015...ESPECIALLY IN
SHOWERS THAT DEVELOP IN THE AFTERNOON.
&&
.MARINE...
TODAY-TONIGHT...
OVERALL THE CONDITIONS LOOK RATHER POOR FOR BOATING. WITH RESPECT
TO WINDS...EAST/SOUTHEAST FLOW SEAWARD OF A COASTAL TROUGH SHOULD
BE AROUND 15 KNOTS. RIGHT NEAR THE COAST...NORTHEAST WINDS MIGHT
BE IN THE 5-10 KNOT RANGE ESPECIALLY FROM THE CAPE NORTHWARD. WITH
RESPECT TO PRECIP...RAIN IS LIKELY FROM THE CAPE NORTHWARD. SOUTH
OF THERE...THE AIR MASS WILL BE VERY MOIST AND SHOWERS ARE
EXPECTED TO DEVELOP WITH JUST A LITTLE DAYTIME HEATING. SOME HEAVY
DOWNPOURS ARE POSSIBLE ESPECIALLY FROM ABOUT SEBASTIAN INLET TO
CANAVERAL DURING THE AFTERNOON.
THU-THU NIGHT...
HAZARDOUS BOATING CONDITIONS. A FRESH TO STRONG SRLY BREEZE WILL
VEER TO THE SW BY LATE AFTN AS A BROAD STORM SYSTEM LIFTS UP THE
ERN SEABOARD...THEN TO THE NW OVERNIGHT AS THE SYSTEM PULLS ITS
COLD FRONT THROUGH CENTRAL FL...NMRS SHRAS AND ISOLD TSRAS
EXPECTED TO ACCOMPANY THE FRONTAL PASSAGE. THE OFFSHORE COMPONENT
WILL LIMIT SEA HEIGHTS BLO 7FT THRU THE DAY BUT ALSO WILL GENERATE
ROUGH WIND CHOP WITHIN SIGHT OF SHORE. SEAS BUILDING TO 5-7FT
NEARSHORE AND 7-9FT OFFSHORE AFT SUNSET AS WIND VEER TO THE NW.
FRI-FRI NIGHT...
LITTLE IMPROVEMENT TO LCL CONDITIONS AS A STRONG HIGH PRES RIDGE
BUILDS OVER THE ERN CONUS AND KEEPS THE COLD FRONT SUPPRESSED OVER
THE FL STRAITS. MODERATE TO FRESH NRLY BREEZE THRU THE
DAY...VEERING TO NE OVERNIGHT. THE OPPOSING NRLY WIND AND SRLY
GULFSTREAM COMPONENTS WILL GENERATE ROUGH SEAS BTWN 6-8FT
NEARSHORE AND 8-9FT OFFSHORE.
SAT-SUN...
WINDS WILL DIMINISH THRU THE WEEKEND AND VEER TO THE E ON SAT...THEN
TO THE SE ON SUN AS THE HI PRES RIDGE PUSHES INTO THE W ATLC AND
WEAKENS. THE SE BREEZE WILL PUSH THE STALLED FRONT BACK INTO
CENTRAL FL AS A WARM FRONT...RAISING THE PROSPECT OF ADDITIONAL
SHRA/TSRA ACTIVITY. ERLY SWELLS WILL IMPACT THE E FL COAST THRU
THE WEEKEND...KEEPING SEAS IN THE 4-6FT RANGE NEARSHORE AND 5-7FT
RANGE OFFSHORE.
&&
.CLIMATE...
RECORD HIGHS FOR JAN 2:
DAB 82 SET IN 2006
MCO 86 SET IN 1924
MLB 85 SET IN 1939
VRB 86 SET IN 1996
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 70 63 78 44 / 80 70 70 40
MCO 75 62 81 47 / 70 60 70 40
MLB 77 67 82 52 / 60 50 50 40
VRB 80 69 82 57 / 60 40 40 40
LEE 70 60 79 41 / 70 70 70 40
SFB 73 63 80 46 / 70 60 70 40
ORL 73 63 80 46 / 70 60 70 40
FPR 79 67 82 58 / 60 40 40 30
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM/AVIATION...LASCODY
LONG TERM/IMPACT WX...BRAGAW
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
341 AM EST WED JAN 1 2014
.DISCUSSION...
TODAY-TONIGHT...
LATEST SURFACE ANALYSIS SHOWS THAT A COASTAL TROUGH HAS ALREADY
SET UP AND WAS EVEN INLAND A LITTLE IN THE SOUTH. AS HIGH PRESSURE
TO THE NORTH PUSHES SEAWARD...A MORE SOUTHERLY WIND COMPONENT WILL
CAUSE THE TROUGH/WARM FRONT TO SHIFT NORTH OF THE AREA TONIGHT.
ISENTROPIC LIFT WAS ALREADY EVIDENT WITH PRECIP ALOFT STREAMING
ACROSS THE NORTH HALF OF THE AREA. A LOW LEVEL DRY LAYER WAS
INHIBITING MUCH RAIN AT THE SURFACE...BUT AS ISENTROP LIFT
CONTINUES TODAY THERE SHOULD BE A GOOD COVERAGE OF RAINFALL
BREAKING OUT ACROSS THE NORTH HALF.
THE 00Z GFS ALSO INDICATED AN AREA OF SHOWERS DEVELOPING NEAR THE
INVERTED TROUGH ALONG THE SPACE/TREASURE COAST THIS AFTERNOON.
SOME LOCAL HEAVY RAINFALL IS POSSIBLE WHERE LOW LEVEL CONVERGENCE
IS MAXIMIZED. MOS POPS TODAY RANGE FROM AROUND 60 PERCENT IN THE
SOUTH TO OVER 80 IN THE NORTH. HAVE ONLY MADE MINOR ADJUSTMENTS TO
THOSE VALUES.
WEAK LOW PRESSURE MOVING ALONG THE BOUNDARY IN THE GULF OF MEXICO
TONIGHT WILL INCREASE SOUTHERLY FLOW AND SHIFT THE WARM FRONT
NORTH OF THE AREA. POPS SHOULD STAY HIGH IN THE NORTH ESPECIALLY
FOR THE EARLY HALF OF THE NIGHT AND HAVE CONTINUED PREVIOUS
FORECAST FOR LIKELY POPS THERE. SOUTHERN SECTIONS WILL GET FULLY
INTO THE WARM SECTOR AND FORECAST SOUNDINGS SHOW DRYING ALOFT BUT
CANNOT RULE OUT A CHANCE OF SHOWERS IN MOIST SOUTHERLY LOW LEVEL
FLOW.
MOSTLY CLOUDY SKIES AND RAIN COOLING WILL CAUSE TEMPS TO STRUGGLE
TO REACH 70 IN THE NORTH. SOUTHERN AREAS MAY EXPERIENCE SOME BRIEF
SOLAR INSOLATION AND ALLOW TEMPS TO BRIEFLY REACH TO AROUND 80
DEGREES. MILD SOUTH FLOW TONIGHT WILL KEEP MINS IN THE 60S AND
POSSIBLY BE AROUND 70 IN THE FAR SOUTH.
THU-THU NIGHT...
AIDED BY A STRONG CONFLUENT H85-H30 FLOW OVER THE ERN CONUS...A
BROAD AREA OF LOW PRES OVER THE HIGH PLAINS WILL RACE INTO THE MID
ATLC BY DAYBREAK THU...THEN UP THE ERN SEABOARD AND INTO THE NW
ATLC. THIS SYSTEM WILL DRAG THE NEXT COLD FRONT THRU CENTRAL FL THRU
THE DAY...PROVIDING A RESPECTABLE CHANCE FOR PRECIP.
CURRENT AIRMASS WILL REQUIRE SOME TIME TO MODIFY AS THE KTBW/KXMR
SOUNDINGS SHOW A SUBSTANTIAL AMOUNT OF DRY AIR THRU THE H100-H70
LYR. DEEPER MOISTURE LURKS TO THE S AND SW...HOWEVER. THE KMFL
SOUNDING SHOWS THE AIRMASS OVER S FL NEARLY SATURATED THRU THE
H100-H60 LYR WHILE THE RUC ANALYSIS SHOWS H100-H70 MEAN RH VALUES
OVER 90PCT BLANKETING THE WRN GOMEX.
A STRONG SRLY FLOW WILL DVLP AHEAD OF THE FRONT THAT WILL GRADUALLY
VEER TO THE SW THRU THE DAY AS THE FRONTAL TROF PLOWS INTO A
MODERATELY STRONG HI PRES RIDGE OVER SW ATLC. THE RESULTING WARM AIR
ADVECTION PATTERN WILL PUSH MAX TEMPS INTO THE U70S/M80S...ABOUT
10-15F ABV AVG...DESPITE EXTENSIVE CLOUD COVER. THIS SHOULD PROVIDE
SUFFICIENT SFC LIFT TO KEEP THUNDER MENTIONED IN THE FCST.
HOWEVER...STRONG/SVR WX APPEARS UNLIKELY AS THE SE CONUS IS
DOMINATED BY A STRONG LIFTING H30-H20 JET THAT WILL PULL THE
MERIDIONAL JET DIGGING OUT OF WRN CANADA TO THE E...KEEPING ITS
ENERGY WELL N OF THE FL PENINSULA.
STRONG COLD AIR ADVECTION WILL DEVELOP OVERNIGHT AS WINDS VEER TO
THE NW BEHIND THE FRONT. GFS/ECMWF BOTH INDICATE THE 560DM THICKNESS
LINE PUSHING S OF THE I-4 CORRIDOR IN THE EARLY MORNING HRS...AND
BOTH MOS OUTPUTS DROP TEMPS INTO THE L/M40S NW OF I-4...M/U50S SPACE
AND TREASURE COASTS. THIS WOULD REPRESENT A 24HR TEMP SWING BTWN
25-30F.
FRI-FRI NIGHT...
STRONG POST FRONTAL HI PRES RIDGE WILL PUSH A DRY/STABLE ACRS
CENTRAL FL. DESPITE MSUNNY SKIES...A DEEP N/NWRLY FLOW WILL GENERATE
A COLD AIR ADVECTION PATTERN THAT WILL KEEP MAX TEMPS A SOLID 10-15F
BLO AVG...L/M50S N OF I-4 AND L/M60S ALONG THE COAST. THE COOL AIR
WILL BEGIN TO MODIFY FRI NIGHT AS WINDS VEER TO THE NE AND BEGIN TO
PUSH WARM OCEAN AIR BACK ONSHORE...MIN TEMPS IN THE M/U40S OVER THE
INTERIOR WILL BE NEAR AVG...M/U50S ALONG THE SPACE AND TREASURE
COASTS WILL BE SLIGHTLY ABV AVG.
SAT-MON...
UPDATE TO FOLLOW.
&&
.AVIATION...
DETERIORATING CONDITIONS WILL OCCUR TODAY AS WARM FRONT LIFTS
SLOWLY UP THE PENINSULA. THIS WILL CAUSE AREAS OF RAIN WITH LOW
MVFR CEILINGS DEVELOPING BY AFTERNOON...ESPECIALLY KISM-KMCO-KTIX
NORTHWARD. MOS HAS CEILINGS THERE A LITTLE BELOW 1000 FEET THIS
AFTERNOON AND BELOW 500 FEET TONIGHT. ITS NOT OUT OF THE QUESTION
TO HAVE LOW LEVEL WIND SHEAR THERE TOO OVERNIGHT. WITH AN INVERTED
TROUGH/WARM FRONT NEAR THE KMLB-KSUA CORRIDOR...THE PRECIP MAY BE
A LITTLE MORE CONVECTIVE IN NATURE BUT STILL EXPECT MVFR CEILINGS
WITH A CHANCE THEY COULD BE AS LOW AS FL015...ESPECIALLY IN
SHOWERS THAT DEVELOP IN THE AFTERNOON.
&&
.MARINE...
TODAY-TONIGHT...
OVERALL THE CONDITIONS LOOK RATHER POOR FOR BOATING. WITH RESPECT
TO WINDS...EAST/SOUTHEAST FLOW SEAWARD OF A COASTAL TROUGH SHOULD
BE AROUND 15 KNOTS. RIGHT NEAR THE COAST...NORTHEAST WINDS MIGHT
BE IN THE 5-10 KNOT RANGE ESPECIALLY FROM THE CAPE NORTHWARD. WITH
RESPECT TO PRECIP...RAIN IS LIKELY FROM THE CAPE NORTHWARD. SOUTH
OF THERE...THE AIR MASS WILL BE VERY MOIST AND SHOWERS ARE
EXPECTED TO DEVELOP WITH JUST A LITTLE DAYTIME HEATING. SOME HEAVY
DOWNPOURS ARE POSSIBLE ESPECIALLY FROM ABOUT SEBASTIAN INLET TO
CANAVERAL DURING THE AFTERNOON.
THU-THU NIGHT...
HAZARDOUS BOATING CONDITIONS. A FRESH TO STRONG SRLY BREEZE WILL
VEER TO THE SW BY LATE AFTN AS A BROAD STORM SYSTEM LIFTS UP THE
ERN SEABOARD...THEN TO THE NW OVERNIGHT AS THE SYSTEM PULLS ITS
COLD FRONT THROUGH CENTRAL FL...NMRS SHRAS AND ISOLD TSRAS
EXPECTED TO ACCOMPANY THE FRONTAL PASSAGE. THE OFFSHORE COMPONENT
WILL LIMIT SEA HEIGHTS BLO 7FT THRU THE DAY BUT ALSO WILL GENERATE
ROUGH WIND CHOP WITHIN SIGHT OF SHORE. SEAS BUILDING TO 5-7FT
NEARSHORE AND 7-9FT OFFSHORE AFT SUNSET AS WIND VEER TO THE NW.
FRI-FRI NIGHT...
LITTLE IMPROVEMENT TO LCL CONDITIONS AS A STRONG HIGH PRES RIDGE
BUILDS OVER THE ERN CONUS AND KEEPS THE COLD FRONT SUPPRESSED OVER
THE FL STRAITS. MODERATE TO FRESH NRLY BREEZE THRU THE
DAY...VEERING TO NE OVERNIGHT. THE OPPOSING NRLY WIND AND SRLY
GULFSTREAM COMPONENTS WILL GENERATE ROUGH SEAS BTWN 6-8FT
NEARSHORE AND 8-9FT OFFSHORE.
SAT-SUN...
WINDS WILL DIMINISH THRU THE WEEKEND AND VEER TO THE E ON SAT...THEN
TO THE SE ON SUN AS THE HI PRES RIDGE PUSHES INTO THE W ATLC AND
WEAKENS. THE SE BREEZE WILL PUSH THE STALLED FRONT BACK INTO
CENTRAL FL AS A WARM FRONT...RAISING THE PROSPECT OF ADDITIONAL
SHRA/TSRA ACTIVITY. ERLY SWELLS WILL IMPACT THE E FL COAST THRU
THE WEEKEND...KEEPING SEAS IN THE 4-6FT RANGE NEARSHORE AND 5-7FT
RANGE OFFSHORE.
&&
.CLIMATE...
RECORD HIGHS FOR JAN 2:
DAB 82 SET IN 2006
MCO 86 SET IN 1924
MLB 85 SET IN 1939
VRB 86 SET IN 1996
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 70 63 78 44 / 80 70 70 40
MCO 75 62 81 47 / 70 60 70 40
MLB 77 67 82 52 / 60 50 50 40
VRB 80 69 82 57 / 60 40 40 40
LEE 70 60 79 41 / 70 70 70 40
SFB 73 63 80 46 / 70 60 70 40
ORL 73 63 80 46 / 70 60 70 40
FPR 79 67 82 58 / 60 40 40 30
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM...LASCODY
LONG TERM....BRAGAW
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1142 PM CST TUE DEC 31 2013
.UPDATE...
ISSUED AT 1133 PM CST TUE DEC 31 2013
THE REMAINDER OF THE WINTER WEATHER ADVISORY FOR TONIGHT HAS BEEN
DROPPED. THE ADVISORY FOR MOST OF THE CENTRAL AND SOUTHERN
COUNTIES REMAINS IN EFFECT FOR WEDNESDAY.
THE SNOW OVER NORTHWEST IL HAS DIMINISHED AND LITTLE IF ANY
ADDITIONAL ACCUMULATION IS EXPECTED THE REST OF THE NIGHT. WE
SHOULD SEE SNOW FROM THE NEXT SYSTEM SPREADING INTO THE AREA LATE
TONIGHT. LATEST MODELS RUNS ARE SUGGESTING THE SNOW WILL SPREAD
INTO THE HIGHWAY 20 CORRIDOR EARLY TOMORROW AND THEN SAGE SOUTH
OVER THE REST OF THE AREA BY EARLY AFTERNOON.
UPDATE ISSUED AT 915 PM CST TUE DEC 31 2013
JUST SENT AN UPDATED WSW AND GRIDS REMOVING EASTERN IOWA COUNTIES
FROM TONIGHTS WSW. THE ADVISORY CONTINUES FROM DUBUQUE...JACKSON
AND CLINTON COUNTIES EAST.
THE FGEN FORCED SNOW THAT HAD BEEN ONGOING ALONG THE HIGHWAY 20
CORRIDOR THIS EVENING HAS SHIFTED EAST AND DEVELOPED FURTHER
SOUTH. SHORT RANGE MODELS INCLUDING THE 00Z/RAP13 AND HRRR HAVE
CAPTURED THIS TREND AND SUPPORT LITTLE IF ANY ADDITIONAL SO
TONIGHT FURTHER WEST. ADDITIONAL ACCUMULATIONS FOR MOST OF THE
AREA WHERE THE ADVISORY REMAINS IN EFFECT WILL PROBABLY BE LESS
THAN AN INCH. HOWEVER WITH THE BANDED NATURE OF THE SNOW...THERE
WILL LIKELY BE SOME NARROW SWATHS OF AN INCH OR TWO ADDITIONAL
SNOWFALL BY 12Z WEDNESDAY.
NO CHANGES WERE MADE TO THE WEDNESDAYS GRIDS INCLUDING SNOWFALL
WITH THE 00Z NAM STILL SUPPORTING A DECENT SNOW FALL CENTRAL AND
SOUTH NEW YEARS DAY.
&&
.SYNOPSIS...
ISSUED AT 304 PM CST TUE DEC 31 2013
THE NARROW AXIS OF MODERATE SNOW IS POSITIONED IN THE NORTHERN 1/4
OF THE CWA BY MID AFTERNOON. BY OBSERVATIONS...WEBCAMS AND
CALLS...THERE HAS BEEN ROUGHLY 1 INCH PER HOUR FALLING IN THIS AREA
SINCE AROUND NOON. FARTHER SOUTH...A STRONG STATIONARY FRONT IS
LOCATED NEAR THE IOWA/MISSOURI BORDER...EASILY SEEN IN OBS THAT
RANGE FROM THE MID 30S TO THE MID TEENS IN A FEW TENS OF MILES IN
OUR SOUTH. STRONG FRONTOGENESIS IS CAUSING THE SNOW TO THE NORTH OF
THE FRONT...AND THIS TYPE OF FORCING WILL ALSO DOMINATE TOMORROW.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 304 PM CST TUE DEC 31 2013
FRONTOGENESIS WILL CONTINUE THROUGH AROUND 9 PM IN THE NORTH...THEN
WILL SLOWLY SETTLE SOUTH IN A WEAKENING FASHION. THIS SHOULD LEAD TO
LIGHTER SNOWS AFTER MID EVENING...BUT WITH 3 TO 5 ALREADY ON THE
GROUND IN THE NORTH...WILL CONTINUE THE ADVISORY THROUGH 12Z.
FARTHER SOUTH ALONG THE HIGHWAY 30 TO INTERSTATE 80 CORRIDORS...THE
BEST CHANCE FOR MEASUREABLE SNOW WILL HOLD OFF UNTIL THIS FORCING
ARRIVES FROM THE NORTH MID EVENING. OVERNIGHT SNOW TOTALS SHOULD BE
1 TO 2 INCHES NORTHEAST TO AN INCH OR INTO THE CENTRAL CWA.
ANOTHER...ARGUABLY STRONGER ROUND OF FRONTOGENESIS ARRIVES EARLY
WEDNESDAY MORNING...LIKELY CONTINUING ALL DAY AS IS GRADUALLY
SETTLES SOUTH. THIS TOO SHOULD HAVE SNOW RATIOS OF 15 TO 20:1...AND
AMOUNTS OF SNOW WILL BE RATHER FLUFFY. THE NAM AND GEM BOTH CARRIED
THIS IDEA IN PAST RUNS AND CURRENT...BUT IS NOW SUPPORTED BY THE 12Z
GFS...12Z ECMWF...12Z UKMET...NMM EAST...SPC WRF AND LAST HOURS OF
THE RAP RUNS. THUS...WE HAVE HIGH ENOUGH CONFIDENCE ISSUE A WINTER
WEATHER ADVISORY SNOW OVER CENTRAL CWA FROM 6 AM WEDNESDAY TO 6 PM
WEDNESDAY. WE ARE GENERALLY LOOKING FOR 3 TO 4 INCHES OF SNOW IN A 6
HOUR WINDOW OF TIME. THIS SUPPORTS ADVISORY ISSUANCE. SHOULD THE
MESOCALE MODELS BE CORRECT ON THE STRENGTH OF FORCING...WE COULD BE
LOOKING AT AMOUNTS WITHIN THE BAND FROM OTTUMWA TO THE QUAD CITIES
IN THE 4 TO 7 INCH RANGE. HOWEVER...CONFIDENCE IS HIGHER FOR TOTALS
IN THE 3 TO 4 INCH RANGE. TEMPERATURES WILL BE VERY COLD AGAIN
TONIGHT AND WEDNESDAY...AS WINDS FROM THE NORTHEAST DRAW IN THE SAME
AIRMASS WE HAD YESTERDAY. THE WARMTH IN THE FAR SOUTH JUST IS NOT
COMING OUR WAY IN THIS FORECAST.
ERVIN
.LONG TERM...(WEDNESDAY NIGHT THROUGH NEXT TUESDAY)
ISSUED AT 304 PM CST TUE DEC 31 2013
WEDNESDAY NIGHT AND THURSDAY...LATEST 12Z RUN MODELS HAVE COME
AROUND WITH RESPECT TO EXTENT OF FORCING ACRS AND SOUTH OF THE CWA
WED EVENING AS UPPER VORT PIVOTS IN TROF BASE ACRS SOUTHEAST IA.
DECENT ELEVATED FRONTOGENESIS RIBBON ALONG AND NORTH OF CENTRAL IL
INTO SOUTHEASTERN PLAINS SFC FRONT...ALONG WITH ISENTROPIC LIFT
ANALYSIS ON 285K SFC SHOULD LAY DOWN AN ADDITIONAL 0.5 UP TO OVER AN
INCH IN THE SOUTHEASTERN QUARTER OF THE DVN CWA FROM 00Z-03Z OR SO
AND WORRIED IT MAY BE MORE TAKING INTO ACCOUNT USED 17:1 OR
HIGHER LSR/S. BUT FOR NOW WILL ALLOW THE ADVISORY END AT 00Z
COORDINATING WITH THE ABOVE SHORT TERM DISCUSSION. THUS EVEN THE
HWY 34 CORRIDOR AND AREAS TO THE SOUTH MAY END UP WITH 1-3 INCHES BY
MIDNIGHT THU NIGHT TAKING INTO ACCOUNT SNOWFALL LATE WED AFTERNOON
AND INTO THE EVENING. THEN AS L/W PHASING PROCESS SHIFTS OFF TO THE
EAST/SOUTHEAST OF THE REGION...ANOTHER BOUT OR INCOMING ARCTIC
HIGH PRESSURE TO DEAL WITH...WITH THE PRESSURE GRADIENT INDUCING OR
MAINTAINING 7-11KT WINDS INTO THU MORNING. SIDING WITH THE COOLER
MAV BUT GOING ABOVE IT TAKING INTO ACCOUNT MIXING WINDS AND
LINGERING CLOUD COVER...STILL MANY SUBZERO READINGS WILL OCCUR OVER
THE NORTHWESTERN THIRD OF THE CWA IN DEEPER SNOWPACK...MAY NOT BE
GOING COLD ENOUGH ALONG THE I80 CORRIDOR. THESE COLD AMBIENT TEMPS
WHEN COMBINED WITH THE WINDS WILL PROBABLY MAKE FOR WIND CHILL
ADVISORY CRITERIA EARLY THU MORNING. BOTH THE 12Z GFS AND ECMWF
SLIDE MAIN SFC RIDGE AXIS ACRS CENTRAL INTO EASTERN IA BY 00Z FRI
MAKING FOR SOME CLOUD CLEAR OUT AS THU PROGRESSES. HIGHS ONLY TO
RECOVER INTO THE SINGLE DIGITS ABOVE ZERO IN MUCH OF THE CWA. THEN
THE STAGE WILL BE SET FOR A NEAR RECORD COLD ARCTIC NIGHT THU NIGHT
INTO FRI MORNING AND AGAIN WILL SIDE WITH THE MUCH COLDER MAV MOS
GUIDANCE VALUES. CID MAY HAVE THE BEST CHC OF BREAKING IT/S RECORD
FOR THE 3RD OF JAN BEING -15F. ALTHOUGH THE WINDS SHOULD BE
DECOUPLING...EVEN 5 KT WINDS WILL PRODUCE SOLID WIND CHILL ADVISORY
AND POSSIBLE EVEN SOME WIND CHILL WARNING CRITERIA LATE THU NIGHT
AFTER 06Z INTO MID FRI MORNING.
FRIDAY THROUGH SUNDAY...ARCTIC RIDGE PROGGED TO MIGRATE OFF TO THE
EAST ON FRI WHICH WILL ALLOW RATHER ROBUST LLVL SOUTHERLY RETURN FLOW
TO BRING ABOUT A SUBSTANTIAL SFC TEMP MODERATION. AFTER SUCH A
FRIGID START TO THE MORNING...12 HR HIGHS WILL OCCUR AT AROUND 00Z
SAT...AND 24 HR HIGHS PROBABLY THROUGH MIDNIGHT FRI NIGHT. THE
LATEST RUN MEDIUM RANGE SOLUTIONS THEN SUGGEST TEMPORARY
FLATTENING FLOW PATTERN TO USHER A MORE VIGOROUS WAVE ACRS THE
NORTHERN PLAINS INTO THE NORTHWESTERN GRT LKS INTO SAT MORNING. WAA
SHIELD OF PRECIP ASSOCIATED WITH THIS FEATURE SHOULD STAY TO THE
NORTH OF THE CWA FRI NIGHT. DISCREPANCIES POP UP WITH THIS SYSTEM/S
SFC FROPA THROUGH THE CWA BY SAT AFTERNOON. THE 12Z ECMWF MAINTAINS
A DRY FROPA...WHILE THE 12Z GFS HAS TRENDED WETTER WITH POST FRONTAL
BAN OF SNOWS ACRS AT LEAST THE NORTHWESTERN THIRD OF THE CWA SAT
AFTERNOON...POSSIBLY 1-3 INCHES OF SNOW ACCUM BY EARLY SAT
EVENING. WILL KEEP SLIGHT CHC TO CHC POPS GOING FOE EXPECTING THE
ECMWF TO TREND WETTER AND PRODUCE SOME PRECIP IN THE CWA. BEFORE
FROPA...MILDEST DAY IN THE PERIOD SAT WITH HIGHS IN THE MID 20S IN
THE NORTH...TO THE LOWER 30S IN THE SOUTH. WOULD BE WARMER IF IT
WERE NOT FOR THE SNOWPACK. RE-ESTABLISHING L/W TROF BASE SOMEWHERE
ACRS THE MID CONUS AND PROBABLY WEST OF OF THE MS RVR VALLEY...AND
WAVE ENERGY EJECTING OUT OF THE DEEP PLAINS LATE SAT NIGHT AND INTO
SUNDAY WILL BE A WINDOW TO WATCH FOR FURTHER NORTHWEST PULL OUT
PATHWAY. RIGHT NOW THE LATEST GFS/ECMWF AND ENSEMBLES JUST CLIP THE
FAR SOUTHERN AND SOUTHEASTERN CWA WITH 1-2+ INCHES BY SUNDAY
AFTERNOON. NORTHERLY LLVL COLD CONVEYOR WRAPPING IN AROUND THIS
FEATURE TO BRING ABOUT COLDER TEMPS AGAIN SAT NIGHT AND SUNDAY.
THEN BULK OF THE MEDIUM RANGE MODELS CONTINUE TO ADVERTISE A HUGELY
NEGATIVE ANOMALY IN THEIR L/W TROF FORMATION ACRS THE UPPER AND MID
MS RVR VALLEY BY 12Z MON. SEEMS THE POLAR VORTEX GYRATING ACRS THE
SOUTHERN HUDSON BAY REGION REMAINS TRAPPED AND ACTING AS A TYPE OF
BLOCK FOR RIDGING OFF THE COASTS.
NEXT MONDAY AND TUESDAY...THE 12Z GFS HAD AN INCREDIBLY INTENSE SFC
HIGH OF 1058 MB INTO NORTH CENTRAL MT BY 12Z MON...WITH THE RIDGE
CENTER THEN MODERATING TO THE LOWER 1040S AS IT SLIDES SOUTHEASTWARD
ACRS THE REGION FOR MON NIGHT INTO TUE MORNING. THE EURO NOT QUITE
SO STRONG WITH A 1045 MB HIGH...BUT THEY BOTH ADVERTISE ARCTIC DOME
OF AIR TO SURGE ACRS THE CWA/FROPA AS MONDAY PROGRESSES. SHARPLY
DROPPING TEMPS...AND IF THE MODEL PROGGED -26C TO -28C H85 MB
AIRMASS VERIFIES AND MAKE IT ACRS THE CWA...COULD BE SOME -15 TO
-25F LOW TEMPS BY TUE MORNING IN PORTIONS OF THE DVN CWA. INCREDIBLE
COLD. WILL IT MODERATE THEN MID TO LATE NEXT WEEK AS BULK OF THE
MEDIUM RANGE SOLUTIONS SUGGEST...OR THEY CONTINUE TO MISHANDLE SUCH
A NEG ANOMALY REGIME AND OPEN THE REGION/MIDWEST BACK TO MORE ARCTIC
DUMPS AFTER NEXT WED. ..12..
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1133 PM CST TUE DEC 31 2013
THE SNOW OVER NORTHWEST ILLINOIS INTO EASTERN IOWA HAS DIMINISHED
AND LITTLE IF ANY REDEVELOPMENT IS EXPECTED THE REST OF THE NIGHT.
WE SHOULD SEE MAINLY VFR CONDITIONS WITH SOME PATCHY MVFR CIGS THE
REST OF TONIGHT. CONDITIONS WILL DETERIORATE WEDNESDAY MORNING AS MORE
SNOW SPREADS OVER THE AREA. IT STILL APPEARS THE
LOWERS...IFR/LIFR...CONDITIONS WILL OCCUR CENTRAL AND SOUTH. THIS
WAS INDICATED IN THE TAFS WITH CONDITIONS AT KMLI AND KBRL
DETERIORATING TO IFR AND LIFR BY LATE WEDNESDAY MORNING. THE SNOW
IS EXPECTED TO DIMINISH WITH IMPROVING FLIGHT CONDITIONS WEDNESDAY
EVENING.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WINTER WEATHER ADVISORY FROM 6 AM TO 6 PM CST WEDNESDAY FOR
CEDAR-CLINTON-DES MOINES-HENRY IA-IOWA-JEFFERSON-JOHNSON-
KEOKUK-LOUISA-MUSCATINE-SCOTT-WASHINGTON.
IL...WINTER WEATHER ADVISORY FROM 6 AM TO 6 PM CST WEDNESDAY FOR
BUREAU-CARROLL-HENRY IL-MERCER-PUTNAM-ROCK ISLAND-WHITESIDE.
MO...NONE.
&&
$$
UPDATE...DLF
SYNOPSIS...ERVIN
SHORT TERM...ERVIN
LONG TERM...12
AVIATION...DLF
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
353 AM CST Wed Jan 1 2014
...Updated for long term discussion...
.SYNOPSIS...
ISSUED AT 339 AM CST WED JAN 1 2014
Water vapor loop during the overnight hours showed a digging
shortwave trough across eastern Wyoming...reaching northern Colorado
as of 09Z. This shortwave trough encompassed a much larger scale
gyre that was centered over southeastern Hudson Bay. In the lower
troposphere, temperatures were fairly mild on the High Plains with
850mb temperatures from +8 to +10C. Meanwhile, the very sharp
baroclinic zone at 850mb was found from northeastern Montana through
northeastern Nebraska per 00Z RAOB and RAP analysis. Surface
temperatures across Nebraska on the 09Z analysis ranged from 35F at
Scottsbluff to +8F at O`Neill on the other side of the front. Below
zero temperatures (degF) were not too far away into southeastern
South Dakota.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 339 AM CST WED JAN 1 2014
As mentioned in the synopsis section, a sharp baroclinic zone was
found across Nebraska. As the mid-level shortwave trough moves
southeast into western Kansas today, some of this arctic air
residing in central Nebraska will advect southward on
northeast...and eventually due north winds. The problem in the
forecast for today is just how far southwest this arctic airmass
will reach. North-northwest winds at the surface near the Colorado
border will not be advecting in much of that arctic air at all (It
was still 31F in Douglas, WY and 35F in Scottsbluff, NE as of
09Z!). We foresee a fairly sharp temperature gradient across
western Kansas today. There is a rather high degree of uncertainty
in the temperature forecast west of Highway 283. The official
forecast will call for steady or falling temperatures through the
day northeast of roughly Dighton to Dodge City to Pratt. Northeast
of this line, there is a fairly high degree of confidence in the
temperature forecast...and that it will be very cold with
temperatures falling through the 20s...and into the mid to upper
teens potentially at Hays. Then there is the
Elkhart-Johnson-Syracuse corridor. This area, if they see any of
this arctic air at all, will be later in the day. This will allow
the Colorado border areas to warm well into the upper 30s to lower
40s. By early to mid afternoon, we could very well see a 30-degree
temperature gradient from southwest to northeast across the DDC
forecast area (from Elkhart to Hays).
Now on to the snow. Nothing much has really changed from previous
forecast thinking. The shortwave trough will be zipping southeast
quickly today, and there will only be a 2 to 4 hour period of light
to briefly moderate snow across the far northeastern zones (most
particularly, Hays-Victoria)...along the zone of strongest 700mb
frontogenesis. The best of this frontogenetic response at 700mb will
be just northeast of the DDC forecast area (across north-central
Kansas) as is indicated by the latest NAM12 and WRF runs. There
could be a brief period of some showery type snow along the Scott
City to Dodge City to Pratt corridor from midday to late afternoon
as a pocket of very slight potential instability develops in the mid
levels right near the 400-500mb potential vorticity anomaly. This
could put down a quickly quarter to half inch of snow in some
scattered spots along the Scott City-Dodge City-Pratt axis.
All of the snow and/or snow showers will be well east of the
southwest Kansas region by early this evening. Downslope
trajectories will resume overnight with a light westerly surface
wind developing especially along/west of Highway 83. Temperatures
should stabilize in the upper teens to lower 20s if not very slowly
rise toward 12Z. Across central Kansas, temperatures will likely
bottom out around +10F.
.LONG TERM...(Thursday through Tuesday)
ISSUED AT 348 AM CST WED JAN 1 2014
A warming trend will commence Thursday and Friday as the mid to
upper level flow becomes more zonal across the Rockies, and surface
pressures fall in the lee of the Rockies. Highs should make it
into the 40s in most places Thursday as the arctic air gets shunted
into eastern Kansas given the increasing low to mid level westerly
momentum. A progressive, positively tilted shortwave trough will
approach from the northwest by Saturday, and as one would expect with
a positively tilted system, a cold surge will pass through western
Kansas ahead of the feature. In spite of the cold advection, some
light snow is possible as the trough approaches, with only minor
accumulations of an inch or less expected. Then by Sunday, a lobe of
the polar vortex will rotate southeastward into the northern plains
and upper midwest. This will provide a glancing blow of arctic air
into Kansas for Sunday night into Monday, with moderating
temperatures by Tuesday and Wednesday into the 30s for highs as the
low level flow quickly becomes more westerly. The next upper
trough will approach Kansas by Wednesday and Thursday, but a lack
of deep moisture may preclude precipitation. However, if this
system is slower and more amplified, then some rain or snow would
be possible.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
ISSUED AT 1158 PM CST TUE DEC 31 2013
The next cold front is due between 10-12Z across the DDC, GCK, HYS
terminals. Behind the front, ceilings are expected to lower into
the MVFR range at anywhere from 1000 to 2000 foot broken or
overcast. Winds will the increase late morning and into the
afternoon from the north at 20 knots sustained with higher gusts.
The snow which is forecast will be light and be confined mainly to
the HYS terminal...where we will drop the visibility to about a
mile for a few hours during the heavier snow which really should
not accumulate much over an inch, if that.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 27 15 38 19 / 30 10 0 0
GCK 30 13 41 18 / 30 10 0 0
EHA 44 19 47 24 / 20 10 0 0
LBL 38 15 45 24 / 20 10 0 0
HYS 20 11 33 15 / 40 10 0 0
P28 30 15 36 17 / 30 40 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...Umscheid
SHORT TERM...Umscheid
LONG TERM...Finch
AVIATION...Umscheid
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
340 AM CST Wed Jan 1 2014
...Updated synopsis and short term sections...
.SYNOPSIS...
ISSUED AT 339 AM CST WED JAN 1 2014
Water vapor loop during the overnight hours showed a digging
shortwave trough across eastern Wyoming...reaching northern Colorado
as of 09Z. This shortwave trough encompassed a much larger scale
gyre that was centered over southeastern Hudson Bay. In the lower
troposphere, temperatures were fairly mild on the High Plains with
850mb temperatures from +8 to +10C. Meanwhile, the very sharp
baroclinic zone at 850mb was found from northeastern Montana through
northeastern Nebraska per 00Z RAOB and RAP analysis. Surface
temperatures across Nebraska on the 09Z analysis ranged from 35F at
Scottsbluff to +8F at O`Neill on the other side of the front. Below
zero temperatures (degF) were not too far away into southeastern
South Dakota.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 339 AM CST WED JAN 1 2014
As mentioned in the synopsis section, a sharp baroclinic zone was
found across Nebraska. As the mid-level shortwave trough moves
southeast into western Kansas today, some of this arctic air
residing in central Nebraska will advect southward on
northeast...and eventually due north winds. The problem in the
forecast for today is just how far southwest this arctic airmass
will reach. North-northwest winds at the surface near the Colorado
border will not be advecting in much of that arctic air at all (It
was still 31F in Douglas, WY and 35F in Scottsbluff, NE as of
09Z!). We foresee a fairly sharp temperature gradient across
western Kansas today. There is a rather high degree of uncertainty
in the temperature forecast west of Highway 283. The official
forecast will call for steady or falling temperatures through the
day northeast of roughly Dighton to Dodge City to Pratt. Northeast
of this line, there is a fairly high degree of confidence in the
temperature forecast...and that it will be very cold with
temperatures falling through the 20s...and into the mid to upper
teens potentially at Hays. Then there is the
Elkhart-Johnson-Syracuse corridor. This area, if they see any of
this arctic air at all, will be later in the day. This will allow
the Colorado border areas to warm well into the upper 30s to lower
40s. By early to mid afternoon, we could very well see a 30-degree
temperature gradient from southwest to northeast across the DDC
forecast area (from Elkhart to Hays).
Now on to the snow. Nothing much has really changed from previous
forecast thinking. The shortwave trough will be zipping southeast
quickly today, and there will only be a 2 to 4 hour period of light
to briefly moderate snow across the far northeastern zones (most
particularly, Hays-Victoria)...along the zone of strongest 700mb
frontogenesis. The best of this frontogenetic response at 700mb will
be just northeast of the DDC forecast area (across north-central
Kansas) as is indicated by the latest NAM12 and WRF runs. There
could be a brief period of some showery type snow along the Scott
City to Dodge City to Pratt corridor from midday to late afternoon
as a pocket of very slight potential instability develops in the mid
levels right near the 400-500mb potential vorticity anomaly. This
could put down a quickly quarter to half inch of snow in some
scattered spots along the Scott City-Dodge City-Pratt axis.
All of the snow and/or snow showers will be well east of the
southwest Kansas region by early this evening. Downslope
trajectories will resume overnight with a light westerly surface
wind developing especially along/west of Highway 83. Temperatures
should stabilize in the upper teens to lower 20s if not very slowly
rise toward 12Z. Across central Kansas, temperatures will likely
bottom out around +10F.
.LONG TERM...(Wednesday night through Tuesday)
ISSUED AT 136 PM CST TUE DEC 31 2013
Cold frontal passages will likely repeat around Saturday with another
chance for accumulating snow, although certainty at this time is
low.
Colder temperatures were forecast for Thursday morning. This was
mainly due to the great agreement in MOS guidance from the WRF
model, ECMWF and GFS as opposed to the warmer mesoscale models. If
widespread stratus develops temperatures may be significantly
warmer, but any stratus is difficult to time. Temperatures were
warmed around 5 degrees on Friday as downslope develops near the
surface trough over extreme eastern Colorado. Afternoon highs could
approach 60 degrees judging by the warm air advection at 850 mb and
ECMWF surface temperatures.
By Saturday, another synoptic scale trough will be rapidly
amplifying across the northern and central Rockies regions. Recent
runs have differed significantly on developing snow along or behind
the surface front. The latest GFS run this morning is more in line
with the ECMWF solution which produces on the order of a tenth of an
inch of QPF in southwest Kansas. Either model might easily produce
up to an inch or two of snow where rates are the best. This
assumption is based on the fact that there is no lower tropospheric
circulation, and the precipitation will be mainly caused by mid
level lift from deformation/frontogenesis, and sufficiently cold air
to produce efficient dendritic growth. Still this morning`s ensemble
forecasts exhibited quite a large range of solutions, the majority
of which left western and central Kansas completely dry. Beyond the
weekend, another surface anticyclone will probably slide south along
the front range Monday into Tuesday. This could play out as a dry
frontal passage or even widespread stratus with weak upslope
enhanced light snow or flurries along and behind the front around
Monday as the GFS/ECMWF indicate. The higher confidence part of the
forecast is falling temperatures heading into Tuesday, when single
digit lows will probably return.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
ISSUED AT 1158 PM CST TUE DEC 31 2013
The next cold front is due between 10-12Z across the DDC, GCK, HYS
terminals. Behind the front, ceilings are expected to lower into
the MVFR range at anywhere from 1000 to 2000 foot broken or
overcast. Winds will the increase late morning and into the
afternoon from the north at 20 knots sustained with higher gusts.
The snow which is forecast will be light and be confined mainly to
the HYS terminal...where we will drop the visibility to about a
mile for a few hours during the heavier snow which really should
not accumulate much over an inch, if that.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 27 16 44 21 / 20 10 0 0
GCK 31 18 45 20 / 20 10 0 0
EHA 46 21 49 26 / 10 10 0 0
LBL 39 21 47 26 / 10 10 0 0
HYS 20 11 34 17 / 80 10 0 0
P28 30 17 40 19 / 20 10 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...Umscheid
SHORT TERM...Umscheid
LONG TERM...Russell
AVIATION...Umscheid
AREA FORECAST DISCUSSION
NWS BISMARCK ND
100 AM CST WED JAN 1 2014
.UPDATE...
ISSUED AT 100 AM CST WED JAN 1 2014
CYCLONIC FLOW ALOFT WITH EMBEDDED ENERGY PASSING THROUGH THE
NORTHERN PLAINS IS COMBINING WITH CONTINUED ISENTROPIC LIFT EAST
OF A SFC TROUGH CURRENTLY POSITIONED OVER THE FAR WESTERN
DAKOTAS TO MAINTAIN EXTENSIVE CLOUDINESS ACROSS WEST AND CENTRAL
NORTH DAKOTA ALONG WITH AREAS OF LIGHT SNOW. INCREASED POPS AND
MAINTAINED HIGH SKY COVER THROUGH 12Z. ANY ADDITIONAL
ACCUMULATIONS WILL BE LIGHT. WHILE CLOUDS REMAIN...CHANCES FOR
LIGHT SNOW WILL DIMINISH FROM WEST TO EAST 09Z THROUGH 15Z AS
ENERGY ALOFT MOVES OUT OF THE REGION AND AS THE SFC TROUGH MOVES
SOUTH AND EAST DECREASING THE OVERRUNNING FLOW.
OVERNIGHT TEMPERATURES SHOULD REMAIN QUASI-STEADY THANKS TO AMPLE
CLOUD COVER AND THE LACK OF CAA. LOWS FROM 15 BELOW OVER MY
EASTERN COUNTIES TO THE SINGLE DIGITS ABOVE SOUTHWEST ARE
FORECAST. THE INHERITED MIN T FORECAST REQUIRED ONLY MINIMAL
TWEAKS...MAINLY TO ADJUST THE HOURLY TREND BASED ON LATEST
OBSERVATIONS.
UPDATE ISSUED AT 934 PM CST TUE DEC 31 2013
LIGHT SNOW CONTINUES TO DISSIPATE AS IT MOVES EAST ACROSS CENTRAL
NORTH DAKOTA. UPDATED POPS BASED ON LATEST RADAR TRENDS...KEEPING
HIGHER CHANCE TO LIKELY POPS FROM AROUND THE HARVEY AREA SOUTHEAST
THROUGH ELLENDALE THROUGH 06 UTC...THEN CHANCE POPS DIMINISHING TO
SLIGHT CHANCE OVER EASTERN PORTIONS OF THE CWA THROUGH MID MORNING
WEDNESDAY. IN THE WEST...KNOCKED BACK POPS TO SLIGHT CHANCE
THROUGH AROUND 08 UTC. THEN BROUGHT A CHANCE OF LIGHT SNOW TO THE
FAR SOUTHWEST FROM 08-15 UTC. LATEST RAP AND HRRR MESOSCALE MODELS
AND THE NEW 01 JAN 14 00 UTC NAM CLIP THE SOUTHWEST WITH LIGHT QPF
ASSOCIATED WITH ANOTHER IMPULSE CURRENTLY DROPPING FORM
ALBERTA/SASKATCHEWAN INTO NORTH CENTRAL MONTANA. WILL CANCEL THE
REMAINING PORTION OF THE WINTER WEATHER ADVISORY. ANY ADDITIONAL
SNOWFALL TONIGHT IS EXPECTED TO BE LIGHT AND WILL NOT ARRIVE UNTIL
THE CURRENT HAZARD ENDS.
UPDATE ISSUED AT 627 PM CST TUE DEC 31 2013
LATEST SATELLITE SHOWS AN IMPULSE MOVING FROM NORTHEAST MONTANA
INTO WESTERN NORTH DAKOTA. LIGHT SNOW CONTINUES TO FALL OVER FAR
SOUTHWEST AND SOUTH CENTRAL NORTH DAKOTA...BUT HAS PRETTY MUCH
ENDED OVER THE NORTHWEST AND WEST CENTRAL FOR NOW. WILL UPDATE THE
WSW TO CANCEL THE ADVISORY FOR PORTIONS OF WEST CENTRAL AND
SOUTHWEST NORTH DAKOTA...MAINLY WATFORD CITY...TROTTERS...
KILLDEER...BEACH AND DICKINSON.
ADJUSTED EVENING POPS BASED ON LATEST RADAR IMAGERY AND THE 23 UTC
RAP. BRINGING HIGH CHANCE LOW QPF SNOWS THE FAR SOUTHWEST AND
CENTRAL THIS EVENING...THEN MOVING SLOWLY EAST AND TAPERING LATE
THIS EVENING AND OVERNIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 305 PM CST TUE DEC 31 2013
MAIN HIGHLIGHTS IN THE SHORT TERM PERIOD ARE THE WINTER WEATHER
ADVISORY SOUTHWEST AND WIND CHILL ADVISORY NORTH AND EAST CENTRAL.
ONLY SUBTLE CHANGES TO PREVIOUS FORECASTS AS THE MAIN IDEAS
MENTIONED ABOVE REMAIN NEARLY THE SAME.
LATEST WATER VAPOR IMAGERY/RADAR LOOP/SURFACE OBSERVATIONS
CONTINUE TO SUPPORT A COUPLE MINOR SHORTWAVES UPSTREAM IN ALBERTA
AND WESTERN SASKATCHEWAN INTERACTING WITH A QUASI-STATIONARY
FRONT IN EASTERN MONTANA AND INTO WESTERN SOUTH DAKOTA. AN INVERTED
SURFACE TROUGH IS FORECAST TO SHIFT ACROSS EASTERN MONTANA EARLY
TONIGHT AND INTO WESTERN NORTH DAKOTA BY 12Z WEDNESDAY...THEN
CONTINUE INTO CENTRAL NORTH DAKOTA BY AROUND 18Z WEDNESDAY. IN
DOING SO...EXPECT A WINDSHIFT TO THE NORTHWEST WHICH WILL
TEMPORARILY SQUASH THE OVERRUNNING PATTERN AND FORCE THE TIGHTEST
PORTION OF THE BAROCLINIC ZONE FARTHER SOUTHWEST. THUS WITH THE
SURFACE TROUGH APPROACHING OVERNIGHT IN COMBINATION WITH THE
AFOREMENTIONED SHORTWAVES AND WEAK FORCING...A HIGH POP/LOW QPF
EVENT WILL BE MAINTAINED IN THE GRIDDED FORECAST. EXPECT A GRADUAL
TRANSITION OF LIGHT SNOW FROM WEST TO EAST OVERNIGHT INTO WEDNESDAY
MORNING ALONG AND AHEAD OF THE SURFACE TROUGH. SNOWFALL AMOUNTS OF
ANOTHER HALF INCH OR SO POSSIBLE THROUGH THE OVERNIGHT PERIOD.
WILL ALLOW THE WINTER WEATHER ADVISORY TO CONTINUE THROUGH TUESDAY
EVENING AS SCHEDULED IN THE SOUTHWEST.
THE WIND CHILL ADVISORY WILL BE MAINTAINED THROUGH 17Z WEDNESDAY
FOR PORTIONS OF NORTH AND EAST CENTRAL NORTH DAKOTA WITH WIND
CHILL TEMPERATURES AS LOW AS 30 BELOW.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 305 PM CST TUE DEC 31 2013
FORECAST CONCERNS AGAIN WILL FOCUS ON THE ARCTIC INTRUSION FORECAST
THIS COMING WEEKEND INTO EARLY NEXT WEEK. WHILE MODEL DIFFERENCES
EXIST...THE MAIN SCENARIO THIS WEEK WILL BE A COLD WEDNESDAY
NIGHT...A WARM UP THURSDAY AND FRIDAY AHEAD OF A POTENTIALLY VIGOROUS
ARCTIC FRONT...AND THE ARRIVAL OF ARCTIC AIR LATE IN THE WEEKEND.
WEDNESDAY NIGHT WILL SEE AN ARCTIC HIGH OVER THE EASTERN DAKOTAS
WITH A WARM FRONT TROUGH IN THE LEE OF THE ROCKIES. A COLD NIGHT
MOST AREAS...WITH LOWS AROUND 15 TO 25 BELOW NORTH AND
CENTRAL...WITH ZERO TO 15 BELOW SOUTHWEST.
SOME MILD AIR ACROSS THE EASTERN PACIFIC WILL BE MOVE ACROSS THE
ROCKIES INTO THE NORTHERN PLAINS THURSDAY...THURSDAY NIGHT...AND
FRIDAY. ON THURSDAY HIGH TEMPERATURES WILL LIKELY BE AROUND ZERO
OVER EASTERN PORTIONS OF CENTRAL NORTH DAKOTA...BUT THE WARM FRONT
WILL NUDGE INTO THE WEST AND FAR WESTERN NORTH DAKOTA SHOULD SEE
TEMPERATURES RISING INTO THE 20S TO AROUND 30 ABOVE BY LATE
AFTERNOON/EVENING THURSDAY. RISING TEMPERATURES ARE ANTICIPATED
THURSDAY NIGHT...AND FRIDAY SHOULD SEE HIGHS IN THE 30S ACROSS ALL
OF WESTERN AND CENTRAL NORTH DAKOTA. ON FRIDAY THERE SHOULD BE A
CHANCE OF RAIN AND SNOW ACROSS THE SOUTHWEST AND PARTS OF THE SOUTH
CENTRAL WITH A CHANCE OF SNOW ELSEWHERE.
THE LEADING EDGE OF COLD ARCTIC AIR WILL ENTER THE NORTHWEST PORTION
OF THE STATE FRIDAY AFTERNOON. RAISED WINDS FROM THE ALLBLEND
GUIDANCE FRIDAY AND FRIDAY NIGHT. THIS FIRST BATCH OF COLD
AIR WILL BE MORE MODERATE...WITH THE MODELS SAVING THE COLDEST AIR
FOR SUNDAY AND MONDAY. LOWS SUNDAY NIGHT SHOULD BE IN THE 15 TO 25
BELOW RANGE...WITH HIGHS MONDAY 5 TO 15 BELOW...AND LOWS MONDAY
NIGHT AGAIN IN THE 15 TO 25 BELOW ZERO RANGE. WIND CHILLS ARE
FORECAST TO REACH DANGEROUS ADVISORY AND WARNING CRITERIA SATURDAY
NIGHT THROUGH TUESDAY - WITH THE LOWEST READINGS EXPECTED SUNDAY
NIGHT THROUGH MONDAY MORNING LIKELY IN THE WARNING CATEGORY (-40 AND
BELOW) ACROSS THE REGION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 100 AM CST WED JAN 1 2014
VFR TO MVFR CIGS ARE EXPECTED THROUGH THE FORECAST PERIOD. WILL
SEE OCCASIONAL LIGHT SNOW AT ALL TERMINALS EXCEPT KDIK. SOUTHEAST
WINDS WILL SLOWLY TRANSITION TO NORTHWEST THIS MORNING INTO
WEDNESDAY EVENING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 11 AM CST THIS MORNING FOR NDZ002>005-
011>013-022-023-025-036-037-047-048-050-051.
&&
$$
UPDATE...NH
SHORT TERM...KS
LONG TERM...JV
AVIATION...NH
AREA FORECAST DISCUSSION
NWS PORTLAND OR
1145 PM PST TUE DEC 31 2013
.SYNOPSIS...STRENGTHENING HIGH PRESSURE TONIGHT WILL ALLOW MORE
VALLEY FOG AND LOW CLOUDS TO DEVELOP AND HANG WITH US THROUGH
THURSDAY MORNING. A STRONGER STORM SYSTEM WILL BRING WIDESPREAD RAIN
TO THE AREA THURSDAY EVENING WITH SNOW LEVELS DROPPING TO PASS LEVELS
LATER THURSDAY NIGHT...BUT ACCUMULATIONS WILL REMAIN LIGHT. HIGH
PRESSURE SHOULD BRING MORE DRY WEATHER TO THE AREA OVER THE WEEKEND
INTO EARLY NEXT WEEK.
&&
.LATE EVENING UPDATE...ISSUED A DENSE FOG ADVISORY FOR THE LOWLANDS.
VISIBILITIES HAVE ALREADY BEEN REPORTED TO BE WELL LESS THAN 1/4 NEAR
THE COLUMBIA RIVER...AND CAMERAS SHOW A CONTINUED LOWERING OF THE
LOW CLOUD DECK. FORECAST SOUNDINGS SUGGEST A CONTINUED STRENGTHENING
OF THE INVERSION WITH THE UPPER RIDGE GETTING CLOSER. GRADIENTS ARE
NEAR NIL THROUGH THE OVERNIGHT HOURS BEFORE AN OFFSHORE GRADIENT
DEVELOPS ON WEDNESDAY. THE HRRR SUGGEST THE LOWEST ELEVATIONS WILL
EVENTUALLY GO CALM WHICH WILL ALLOW THE DENSE FOG TO BECOME MORE
WIDESPREAD MORESO OVERNIGHT BEFORE OFFSHORE GRADIENTS INCREASE...BUT
WANTED TO GET THE HEADS UP FOR LATE NIGHT TRAVELERS THAT POCKETS OF
DENSE FOG HAVE ALREADY BEGUN. WHILE FREEZING FOG IS NOT A
WIDESPREAD CONCERN...TEMPERATURES IN CORVALLIS ARE ALREADY AT
FREEZING AND EUGENE IS CLOSE. TEMPERATURES ARE WARMER FARTHER NORTH
WHERE LESS CLEARING OCCURRED BEFORE FOG DEVELOPMENT AND WHERE
SIGNIFICANTLY HIGHER DEWPOINTS EXIST. /KMD
&&
.SHORT TERM...DISCUSSION UNCHANGED...
.TONIGHT THROUGH WEDNESDAY NIGHT...MAIN CHANGES TO THE FORECAST
PACKAGE THIS EVENING WILL CENTER AROUND TEMPERATURES OVERNIGHT. A
MILD AND MOIST AIR MASS IS SETTLING IN ACROSS THE DISTRICT...WITH
DEWPOINTS GENERALLY WITHIN A FEW DEGREES OF 40 F. SKIES HAVE MOSTLY
CLEARED SALEM SOUTHWARD WHICH HAS ALLOWED TEMPS/DEWPOINTS TO FALL
INTO THE MID TO UPPER 30S IN THE VALLEYS...BUT THIS WILL ONLY PROMOTE
FOG FORMATION OVERNIGHT. SUSPECT ONLY A FEW OUTLYING VALLEYS WILL
FALL BELOW FREEZING. FOG MAY BECOME RATHER DENSE OVERNIGHT IN THE
CENTRAL AND SOUTH WILLAMETTE VALLEY...LINGERING INTO NEW YEARS
MORNING.
WARMER AIR MOVING IN ALOFT WILL ONLY SERVE TO STRENGTHEN VALLEY
INVERSIONS OVER THE NEXT 24-36 HOURS. MEANWHILE LOW-LEVEL FLOW WILL
REMAIN LIGHT. AS A RESULT EXPECT THE VALLEY FOG AND LOW CLOUDS WHICH
FORM TONIGHT TO LINGER THROUGH MOST OF NEW YEARS DAY...THEN THICKEN
AGAIN WEDNESDAY NIGHT/EARLY THURSDAY. AREAS ABOVE THE VALLEY
INVERSIONS SHOULD SEE ANOTHER PARTLY TO MOSTLY SUNNY AND MILD NEW
YEARS DAY AS AN UPPER RIDGE STRENGTHENS OVER THE DISTRICT. ONLY
MINOR TWEAKS WERE MADE TO THE FORECAST THU/FRI...SO THE PREVIOUS
DISCUSSION REMAINS VALID.WEAGLE
.THURSDAY AND FRIDAY...A STRONG SHORTWAVE TROUGH WILL SLIDE EASTWARD
INTO WESTERN WASHINGTON LATE IN THE DAY. MODELS CONTINUE TO SUGGEST
THE BEST UPPER LEVEL DYNAMICS WILL REMAIN GENERALLY NORTH OF THE
COLUMBIA RIVER. HOWEVER...A TRAILING COLD FRONT WILL STILL PROVIDE
ENOUGH LIFT TO GENERATE WIDESPREAD PRECIPITATION OVER NORTHWEST
OREGON. HOWEVER...QPF AMOUNTS WILL GENERALLY BE LESS FARTHER SOUTH.
SNOW LEVELS WILL FALL BELOW PASS LEVELS...BUT AT THIS
POINT...INSTABILITY APPEARS IT WILL BE QUITE SHALLOW BEHIND THE COLD
FRONT. AS A RESULT...CASCADES PASSES SHOULD SEE LITTLE MORE THAN AN
INCH OR TWO OF SNOW LATE THURSDAY NIGHT. EXPECT SHOWERS TO GENERALLY
DECREASE FRIDAY...BUT THE EC DOES SUGGEST INSTABILITY MAY HANG WITH
US A BIT LONGER AS A SECONDARY SHORTWAVE TROUGH CLIPS OUR CASCADES.
/NEUMAN
.HYDROLOGY...THE HIGHEST TIDE OF THE 13/14 WINTER WILL BE ON NEW
YEARS DAY. WHILE RIVERS ARE LOW FOR THIS TIME OF YEAR AND TIDAL
ANOMALIES ARE NOTHING TO WRITE HOME ABOUT...THERE IS A CHANCE A FEW
ROADS ALONG THE COAST MAY HAVE AN ISSUE WITH FLOODING. THE MAIN AREA
OF CONCERN IS AROUND TILLAMOOK WHERE TILLAMOOK RIVER...FRASIER AND
BROUTON ROADS MAY BE VULNERABLE TO BRIEF FLOODING DURING HIGH TIDE ON
NEW YEARS DAY. /NEUMAN
.LONG TERM...SATURDAY THROUGH TUESDAY...MODELS GENERALLY AGREE A
SHORTWAVE RIDGE WILL SLOWLY SHIFT FROM WEST TO EAST ACROSS THE
REGION. THIS SHOULD ALLOW THE COAST...FOOTHILLS AND AREAS NEAR THE
COLUMBIA RIVER GORGE TO CLEAR. THE WILLAMETTE VALLEY WILL LIKELY SEE
MORE FOG AND LOW CLOUDS. SKY COVER WAS ADJUSTED ACCORDINGLY. A
SPLITTING STORM SYSTEM WILL BRING A CHANCE FOR PRECIPITATION
TUESDAY-ISH...BUT CONSIDERABLE UNCERTAINTY EXISTS. /NEUMAN
&&
.AVIATION...VARIABLE MID AND HIGH CLOUDS OVER REGION TONIGHT INTO
WED. WILL SEE MVFR OR POSSIBLY HIGH END IFR STRATUS WITH ONLY
PATCHY FOG REFORM N OF A KTMK TO KMMV TO KUAO LINE. TO SOUTH OF
THAT LINE MORE BREAKS IN CLOUD COVER WILL LEAD TO WIDESPREAD FOG
AND IFR STRATUS TO REFORM. ANY CLOUDS AND FOG WILL GRADUALLY LIFT
ON WED...BUT VFR NOT EXPECTED TIL AFTER 20Z. COASTAL AREA REMAIN
IN MOIST AIR MASS...SO EXPECT CONTINUED IFR TO LOW END MVFR CIGS
AND VIS.
KPDX AND APPROACHES...CURRENTLY VFR CONDITIONS...WITH CIGS 3500 TO
4500 FT. NOT MUCH CHANGE THROUGH WED AM...THOUGH WILL SEE CIGS
CLOSER 1000 TO 1500 FT FROM 08Z TO AT LEAST 18Z. WILL LIFT BACK TO
VFR CIGS WED AFTERNOON. ROCKEY.
&&
.MARINE...RATHER QUIET CONDITIONS CONTINUE NEXT FEW DAYS. SEAS
HOLDING 6 TO 7 FT...AND WILL CONTINUE TO SLOWLY SUBSIDE TONIGHT.
NEXT THREAT OF ENHANCED WINDS NOT UNTIL LATER THU NIGHT AND FRI
WHEN A FRONT WILL PUSH ACROSS THE REGION. THIS FRONT LIKELY TO POP
20 TO 25 KT S WINDS...WITH SEAS BUILDING BACK TO 10 FT ON FRI.
THEN HIGH PRESSURE IS EXPECTED TO REDEVELOP... KEEPING CONDITIONS
RATHER BENIGN ON SAT AND SUN. RAMHARTKEY
&&
.CLIMATE...AS 2013 COMES TO A CLOSE...IT WILL GO DOWN IN THE BOOKS
AS THE DRIEST CALENDAR YEAR IN RECORDED HISTORY FOR MANY LOCATIONS
ALONG THE WEST COAST OF THE UNITED STATES. OUR FORECAST AREA WILL BE
NO EXCEPTION...THE 21.19 INCHES OF RAIN RECORDED THIS YEAR IN EUGENE
WILL BREAK THE PREVIOUS RECORD BY MORE THAN 2 INCHES. IMPRESSIVE
CONSIDERING RECORDS FOR EUGENE GO ALL THE WAY BACK TO 1890.
SALEM...ANOTHER SITE WITH RECORDS DATING BACK TO THE LATE 19TH
CENTURY...WILL ALSO SEE 2013 GO DOWN AS THEIR DRIEST YEAR ON RECORD.
ANOTHER ODDITY OF 2013 IS THAT SEPTEMBER WAS THE WETTEST MONTH OF
THE YEAR FOR ALL OF OUR PRIMARY CLIMATE SITES. NORMALLY SEPTEMBER IS
ONE OF THE 4 DRIEST MONTHS OF THE YEAR ACROSS NORTHWEST OREGON.
A RECORD EVENT REPORT WILL BE SENT SHORTLY TO HIGHLIGHT THE HISTORIC
DRY WEATHER WE EXPERIENCED IN 2013.
HAPPY NEW YEAR TO ALL. I AM SURE MANY PEOPLE ALONG THE WEST COAST
ARE WISHING FOR MORE RAIN IN 2014...AND THE ODDS ARE HIGHLY IN THEIR
FAVOR.WEAGLE
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY FOR THE WILLAMETTE VALLEY AND PORTLAND METRO
AREA THROUGH 10 AM WEDNESDAY.
AIR STAGNATION ADVISORY UNTIL 4 PM PST THURSDAY FOR CENTRAL
WILLAMETTE VALLEY-SOUTH WILLAMETTE VALLEY.
WA...DENSE FOG ADVISORY FOR THE GREATER VANCOUVER METRO AREA THROUGH
10 AM WEDNESDAY.
PZ...SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM
2 AM TO 6 AM PST WEDNESDAY.
&&
$$
MORE WEATHER INFORMATION ONLINE AT..
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1028 PM CST TUE DEC 31 2013
.UPDATE...
ISSUED AT 842 PM CST TUE DEC 31 2013
WHILE THE OVERALL THINKING OF THE FORECAST IN TERMS OF
DYNAMICS/FORCING REMAINS SIMILAR TO WHAT IS DISCUSSED
BELOW...HAVE MADE SOME CHANGES IN RESPONSE TO LATEST MODEL RUNS
AND CURRENT WEATHER. FIRST OF ALL...DID GO AHEAD AN ISSUE A WIND
CHILL ADVISORY FOR PORTIONS OF THE HIGHWAY 14 CORRIDOR/MOST OF
SOUTHWEST MINNESOTA AND INTO THE IOWA GREAT LAKES AREA FOR THE
REMAINDER OF TONIGHT INTO WEDNESDAY MORNING. THE REASONING BEHIND
THIS IS THAT TEMPERATURES HAVE BEEN DROPPING QUICKER THAN THOUGHT
OVER THAT AREA...AND WINDS HAVE REMAINED A LITTLE STRONGER THAN
FORECASTED. STILL ANTICIPATE THAT WINDS WILL TAPER DOWN LATER IN
THE NIGHT AS THE GRADIENT RELAXES A BIT...BUT EVEN SO...WITH
TEMPERATURES AROUND 10 BELOW ZERO OVER THAT AREA...WIND CHILL
VALUES OF 20 TO 25 BELOW ZERO WILL BE REALIZED OVERNIGHT.
OUR ATTENTION THEN TURNS TO THE SNOW POTENTIAL ACROSS MOST OF THE
AREA LATER TONIGHT INTO EARLY WEDNESDAY MORNING. STILL HAVING RUN
TO RUN DIFFERENCES IN THE MODELS...WITH THE 00Z NAM NOW TRENDING
BACK TO THE SOUTH. THIS ALIGNS IT WELL WITH MOST OTHER MODELS
PUTTING THE BRUNT OF THE PRECIPITATION THROUGH THE MISSOURI RIVER
CORRIDOR...OUTSIDE OF THE 12Z GEM WHICH TAKES IT FARTHER TO THE
NORTH. WHAT IS A LITTLE MORE DISTURBING IS THAT LATEST MODELS
CONTINUE TO COME IN A LITTLE WETTER. IN LIGHT OF THAT...UPPED QPF
AMOUNTS ACROSS THAT AREA...YIELDING SNOWFALL TOTALS CLOSER TO 3
INCHES. CANNOT RULE OUT LOCALIZED HIGHER AMOUNTS...PUSHING INTO
ADVISORY CRITERIA...BUT THINK THAT MOST OF THE EFFECTED AREA WILL
REMAIN JUST BELOW THAT. UPDATES ARE OUT.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 339 PM CST TUE DEC 31 2013
SNOW ASSOCIATED WITH TODAYS WAVE IS EXITING THE AREA...WITH JUST
SOME ISOLATED TO SCATTERED FLURRIES LINGERING. ANOTHER WAVE WILL RIDE
SOUTHEAST ALONG THE THERMAL GRADIENT TONIGHT. MODELS HAVE HAD GREAT
DIFFICULTY PINPOINTING WHERE THE BEST SNOW POTENTIAL WILL BE WITH
THIS WAVE...AND HOW MUCH QPF WILL FALL. THUS NEEDLESS TO SAY A LOW
CONFIDENCE FORECAST. BEST LARGE SCALE FORCING FROM THE WAVE SEEMS TO
GO TO OUR SOUTH. HOWEVER THE MID LEVEL FRONTAL BOUNDARY SHOULD BE
FURTHER NORTH...IN THE VICINITY OF THE MISSOURI RIVER VALLEY. LATEST
MODELS ARE TRENDING THE AREA OF SNOW FURTHER NORTH...CLOSER TO THE
REGION WHERE ISENTROPIC LIFT OVER THE MID LEVEL FRONT INTERACTS WITH
SOME OF THE LARGE SCALE FORCING. MODELS ALSO SHOWING SOME WEAK
INSTABILITY ABOVE THE FRONT...SUGGESTING WE COULD SEE SOME ENHANCED
BANDING. THE THERMAL PROFILE DOES FEATURE A DECENT SIZED AREA IN THE
DENDRITIC SNOW GROWTH ZONE...SUGGESTING RATIOS COULD END UP AROUND
15 TO 1. A CONSENSUS OF MODEL QPF VALUES SUGGEST 1 TO 2 INCHES IN
THE SNOW BAND...WITH ISOLATED AMOUNTS UP TO 3 INCHES IF RATIOS END
UP A BIT HIGHER. HOWEVER THE RUC...HRRR AND 18Z NAM ARE ALL MUCH
MORE AGGRESSIVE WITH QPF VALUES. THESE THREE WOULD SUGGEST A BAND OF
3 TO 5 INCHES. GIVEN THE LARGE SCALE FORCING...POTENTIAL BANDING AND
MODELS TRENDING UPWARD IN QPF...THIS CAN NOT BE COMPLETELY RULED
OUT. HOWEVER DO NOT WANT TO JUMP ON THIS AT THIS POINT GIVEN THE
REST OF THE GUIDANCE SUGGESTING LOWER AND THE MODEL INCONSISTENCY
FROM RUN TO RUN. THUS...TRENDED AMOUNTS UP...BUT ONLY TOWARDS MODEL
CONSENSUS...WHICH AT THIS TIME STILL SEEMS LIKE THE MORE LIKELY
SOLUTION.
THE NEXT QUESTION IS EXACTLY WHERE THIS BAND SETS UP. RIGHT
NOW ALMOST ALL GUIDANCE SUGGESTS THE MISSOURI RIVER VALLEY IS THE
MOST LIKELY LOCATION...WITH DECREASING AMOUNTS AS YOU GET TOWARDS
INTERSTATE 90. HOWEVER THE GEM AND HRRR ARE FURTHER NORTH...PUTTING
THE HIGHER AMOUNTS CLOSER TO OR JUST SOUTH OF INTERSTATE 90. FOR
THIS FORECAST PACKAGE WILL GO WITH THE MORE LIKELY SOLUTION ALONG
THE MISSOURI RIVER...BUT GIVEN THE RECENT NORTHWARD TRENDS CAN NOT
COMPLETELY RULE OUT THE HRRR AND GEM SOLUTION. SO FOR NOW...WILL
STICK WITH THE 1 TO 3 INCHES ALONG THE MISSOURI RIVER...DECREASING
TO AROUND AN INCH IN SIOUX FALLS AND LESS TO THE NORTH...BUT AS
MENTIONED ABOVE...EVENING SHIFT WILL NEED TO MONITOR TRENDS AND SEE
IF ADJUSTMENTS ARE NEEDED. EXPECT SNOW TO START AROUND 10 PM IN OUR
WEST...APPROACH SIOUX FALLS AND SIOUX CITY CLOSER TO MIDNIGHT...AND
SPENCER TO STORM LAKE AROUND 2 AM.
IT WILL BE A COLD ONE TONIGHT AS WELL WITH LOWS IN THE SINGLE DIGITS
BELOW ZERO NORTH OF INTERSTATE 90 AND SINGLE DIGITS ABOVE TO THE
SOUTH. KEPT THE TREND OF STAYING ON THE WARMER SIDE OF GUIDANCE
THOUGH...GIVEN THE CLOUD COVER AND AT LEAST A WEAKLY MIXED BOUNDARY
LAYER. WIND CHILLS WILL BE AROUND THE 20 BELOW ZERO ADVISORY CRITERIA
IN OUR NORTH. HOWEVER DECIDED TO HOLD OFF ON ONE AT THIS TIME...AS
WINDS SHOULD DROP OFF AFTER SUNSET AND GENERALLY BE UNDER 10
MPH...AND IF WINDS STAY UP MORE...TEMPERATURES WILL PROBABLY STAY A
BIT WARMER THAN FORECAST. THUS FEEL LIKE WIND CHILLS WILL HOVER A
FEW DEGREES EITHER SIDE OF 20 BELOW...AND GIVEN OUR COLD WINTER THUS
FAR...WILL NOT ISSUE ANOTHER ADVISORY AT THIS TIME. SNOW SHOULD EXIT
THE AREA FROM NORTHWEST TO SOUTHEAST ON WEDNESDAY MORNING...GIVING
WAY TO A MOSTLY CLOUDY DAY WITH JUST SOME SCATTERED FLURRIES. HIGHS
WILL WILL ONLY BE IN THE SINGLE DIGITS ABOVE AND BELOW ZERO WITH
WIND CHILLS LIKELY STAYING BELOW ZERO THROUGH THE DAY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 339 PM CST TUE DEC 31 2013
CONTINUED COLD WEATHER PATTERN LOCKED IN PLACE FOR THE MAJORITY OF
THE MID AND LONG RANGE FORECAST. PREDOMINATE NORTHWEST UPPER LEVEL
FLOW WILL USHER IN SEVERAL WAVES THROUGH THE PERIOD WHICH WILL
PROVIDE REINFORCING SHOTS OF ARCTIC AIR. THE FIRST BLAST OF COLD AIR
CONTINUES TO SPREAD ACROSS THE REGION WEDNESDAY NIGHT. LIGHT
NORTHERLY WINDS AND DECREASING CLOUDS WILL LEAD TO EXTREMELY COLD
LOWS IN THE TEENS BELOW ZERO ACROSS THE BULK OF THE FORECAST
AREA...WITH THE SINGLE DIGITS BELOW CLOSER TO THE MISSOURI RIVER.
WIND CHILLS WILL BE BRUTALLY COLD AROUND 20 TO 30 BELOW FOR A LARGE
AREA...BUT WINDS SHOULD REMAIN WELL BELOW THE 10 MPH THRESHOLD FOR A
WIND CHILL HEADLINE.
THURSDAY WILL AGAIN BE VERY COLD WITH LIGHT WINDS TURNING A LITTLE
MORE SOUTHERLY IN THE AFTERNOON AS SURFACE HIGH PRESSURE SLIPS OFF
TO OUR EAST. MOSTLY CLEAR SKIES IN THE MORNING WILL SEE AN INCREASE
IN CLOUD COVER FROM THE WEST LATER IN THE DAY AHEAD OF THE NEXT
INCOMING SHORTWAVE. TEMPERATURES WILL NOT WARM MUCH...WITH MANY
LOCATIONS ONLY REACHING HIGHS AROUND ZERO. RETURN FLOW INCREASES
THURSDAY NIGHT AND FRIDAY...LEADING INTO THE ONLY MILD DAY OF THE
PERIOD. AFTER A SLIGHT DIP IN TEMPERATURES THURSDAY EVENING...
TEMPERATURES SHOULD BEGIN RISING OVERNIGHT WHILE CLOUDS INCREASE.
SOUTHERLY WINDS BECOME BREEZY ON FRIDAY...ESPECIALLY ACROSS OUR
EASTERN HALF...HOWEVER HIGHS ARE EXPECTED TO IMPROVE SOME 20 DEGREES
OR MORE FROM THURSDAY HIGHS. BLOWING AND DRIFTING OF THE RECENT
SNOWFALL COULD BE A CONCERN AS THE WINDS INCREASE ON FRIDAY.
STRONG COLD FRONT DIVES ACROSS THE REGION ON FRIDAY NIGHT...BRINGING
THE NEXT CHANCE OF SOME LIGHT SNOW ALONG AND BEHIND THE FRONT. UPPER
LEVEL TROUGH SINKS SOUTH OF THE FORECAST AREA LATE SATURDAY
NIGHT...USHERING IN ANOTHER ARCTIC BLAST FOLLOWED BY A REINFORCING
SHOT OF COLD AIR LATE SUNDAY AND SUNDAY NIGHT. LOW TEMPERATURES WILL
BE BACK INTO THE TEENS BELOW ZERO SUNDAY NIGHT AND MONDAY
NIGHT...WITH HIGHS EXPECTED TO BE BELOW ZERO FOR THE MAJORITY OF THE
FORECAST AREA. NORTHWEST WINDS ARE EXPECTED TO BE BREEZY SUNDAY
NIGHT INTO MONDAY WHICH PLACES NEARLY THE ENTIRE FORECAST AREA
SQUARELY INTO WIND CHILL WARNING TERRITORY AND AS COLD AS 35 TO 45
BELOW ZERO.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1024 PM CST TUE DEC 31 2013
LIGHT SNOW WILL CONTINUE TO DEVELOP AND OVERSPREAD THE AREA
OVERNIGHT WITH CEILINGS LOWERING INTO THE MVFR RANGE. THE BETTER
CHANCES OF SNOW WILL BE SOUTH OF INTERSTATE 90...FOCUSED THROUGH
THE MISSOURI RIVER CORRIDOR INTO NORTHWESTERN IOWA. VISIBILITIES
WILL DROP INTO THE IFR RANGE IN HEAVIER SNOW ACTIVITY. LIGHT SNOW
IS EXPECTED TO TAPER OFF AFTER 12Z ON WEDNESDAY...THOUGH WILL MOST
LIKELY HOLD ON TO LOWER CEILINGS THROUGH THE DAY.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WIND CHILL ADVISORY UNTIL 9 AM CST WEDNESDAY FOR SDZ038>040-
054>056.
MN...WIND CHILL ADVISORY UNTIL 9 AM CST WEDNESDAY FOR MNZ071-072-080-
081-089-090-097.
IA...WIND CHILL ADVISORY UNTIL 9 AM CST WEDNESDAY FOR IAZ002-003-013-
014.
NE...NONE.
&&
$$
UPDATE...JM
SHORT TERM...CHENARD
LONG TERM...
AVIATION...JM
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1017 PM PST Tue Dec 31 2013
.SYNOPSIS...
Weak high pressure will move over the Inland Northwest through
Wednesday although a few lingering areas of light rain and snow
will remain possible mainly in the Idaho Panhandle. A stronger
storm system will pass through Thursday night bringing mainly rain
in the valleys and snow in the mountains. A cooler and drier
pattern is expected this weekend into early next week.
&&
.DISCUSSION...
Update: A shortwave disturbance has slid into the central ID
Panhandle early this evening. The RUC model seems to have a good
handle on this piece of energy and slides it southeast of the
region by 8:00 PM tonight. Radar imagery already shows showers
across the area winding down as drier air aloft filters into the
region behind this disturbance. I expect this drying trend to
continue and updated the forecast to trend down our precip chances
through tonight. The only area expected to see some light snow
will be in the Central Panhandle Mountains, but will not be of
much concern. Other forecast updates were to expend the fog threat
to the south a bit faster and to include the Palouse region. The
L-C Valley is a tougher call for fog tonight as their dew point
depression is still a bit high. With temperatures remaining around
the freezing mark, any dense fog that forms will have the potential
for creating slick travel conditions. /SVH
&&
.AVIATION...
06Z TAFS: Widespread low stratus and fog is filling its way
southward into the Upper Columbia Basin late this evening. KGEG,
KSFF, KCOE and KMWH will likely see IFR/LIFR cigs/vis through at
least the late morning hours on Wednesday. Confidence is lower at
how much these low clouds will impact KEAT, KPUW and KLWS taf
locations. Satellite imagery shows a southward and westward trend of
low clouds filling in toward KEAT and is anticipated that IFR cigs
will develop some time between 09-12Z. Easterly and southeasterly
flow is expected to keep much of the stratus north and west of KPUW
and LWS, but some shallow fog at either taf site can not be ruled
out. /SVH
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 26 36 28 38 31 38 / 10 10 10 20 70 20
Coeur d`Alene 29 38 27 40 30 37 / 10 10 10 20 80 30
Pullman 30 40 29 41 32 39 / 10 10 0 10 70 40
Lewiston 31 41 31 45 35 45 / 10 10 0 10 50 40
Colville 25 33 27 33 29 35 / 10 20 30 30 60 20
Sandpoint 28 36 27 37 29 37 / 10 20 30 40 90 30
Kellogg 31 37 29 38 31 35 / 50 20 20 30 90 60
Moses Lake 22 35 26 36 25 40 / 0 0 10 10 20 10
Wenatchee 26 36 27 36 27 40 / 0 0 0 10 20 10
Omak 22 32 25 32 24 36 / 0 10 10 20 30 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...Air Stagnation Advisory until Noon PST Friday for East Slopes
Northern Cascades-Moses Lake Area-Northeast Mountains-
Okanogan Highlands-Okanogan Valley-Spokane Area-Upper
Columbia Basin-Waterville Plateau-Wenatchee Area.
&&
$$
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1045 PM MST TUE DEC 31 2013
.UPDATE...
ISSUED AT 1040 PM MST TUE DEC 31 2013
WINDS REMAIN UP IN OUR WIND PRONE AREAS THIS EVENING...DESPITE
GUIDANCE SHOWING THESE WINDS SHOULD BE COMING DOWN NOW. WENT AHEAD
AND EXTENDED THE HIGH WIND WARNINGS TO 3 AM SO THE MID SHIFT CAN
REASSESS. UPDATES HAVE BEEN SENT.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 245 PM MST TUE DEC 31 2013
TONIGHT...PRIMARY CHALLENGES...AS ARE QUITE TYPICAL THIS TIME OF
YEAR...ARE WINDS AND SNOW.
WINDS AT BORDEAUX...ALONG INTERSTATE 25 IN PLATTE COUNTY...AND AT
ARLINGTON...ALONG INTERSTATE 80 IN EASTERN CARBON COUNTY...STILL
GUSTING NEAR 60 MPH AT MID AFTERNOON. SUSPECT WINDS AND WIND GUSTS
IN OUR HIGH WIND WARNING AREA...WILL CONTINUE TO SLOWLY DECREASE
THROUGH THE EARLY EVENING HOURS AT MID LEVEL HEIGHT GRADIENTS WEAKEN
AND 500-300 MB AND 700-500 MB QUASIGEOSTROPHIC RISING MOTION ADVECTS
ACROSS OUR COUNTIES...THUS WILL LEAVE THE HIGH WIND WARNING INTACT
AND LET THE EVENING FORECAST TEAM ASSESS THE APPROPRIATE TIME TO END
THE HIGH WIND WARNING.
AS FOR SNOW...INHERITED WINTER WEATHER ADVISORY FOR OUR SIERRA MADRE
AND SNOWY RANGES TONIGHT AND WEDNESDAY MORNING LOOKS QUITE PLAUSIBLE
AND ON TRACK. PROGRESSIVE POSITIVELY TILTED SHORTWAVE TROUGH ALOFT
SLIDES SOUTHEAST OVER OUR COUNTIES...WITH AN IMPRESSIVE 500-300 MB
AND 700-500 MB QUASIGEOSTROPHIC UPWARD VERTICAL MOTION COUPLET
MOVING ACROSS OUR COUNTIES BY LATE TONIGHT...WITH DOWNWARD MOTION
INDICATED IN THESE LEVELS WEST OF INTERSTATE 25 TOWARDS DAYBREAK.
FORTUNATELY...FOR TRAVEL PURPOSES ON THIS NEW YEARS EVE...LOOKS LIKE
THE BULK OF THE AREAL SNOW COVERAGE WILL NOT OCCUR UNTIL AFTER
MIDNIGHT TONIGHT.
BASED ON PROJECTED MOISTURE DEPTH...PROGRESSIVE TRACK OF THE
SHORTWAVE TROUGH...MODEL QPF FROM THE NAM...GFS AND ECMWF...FORECAST
WEATHER PREDICTION CENTER...WPC...QPF...THE WINTER WEATHER ADVISORY
WILL LIKELY PAN OUT WITH HIGHER SNOWFALL ACROSS THE SIERRA MADRE
RANGE...TO THE WEST OF THE SNOWY RANGE OVER SOUTHERN CARBON COUNTY.
A FEW OTHER LOWER ELEVATION LOCALES...WEST OF INTERSTATE 25...COULD
SEE 3 TO 4 INCHES OF SNOW...BUT BELIEVE AMOUNTS WILL BE PRIMARILY
LESS THAN 3 INCHES AT LOWER ELEVATIONS...THUS NO ADDITIONAL WINTER
WEATHER ADVISORIES WILL BE ISSUED. MODELS LOOK ERRONEOUSLY TOO LOW
WITH POPS...AND HAVE GONE WITH 50 TO 100 PERCENT POPS FOR LATE
TONIGHT CONSIDERING OUR FAVORED UPSLOPE AND OROGRAPHICALLY FAVORED
LOCALES.
NEW YEARS DAY...PROGRESSIVE SHORTWAVE TROUGH ALOFT MOVES SOUTHEAST
OF OUR COUNTIES...THUS EXPECT AREAL SNOW COVERAGE TO DECREASE...
THOUGH ENOUGH LOW AND MID LEVEL MOISTURE AND CYCLONIC CURVATURE
ALOFT TO KEEP AT LEAST A CHANCE OF LIGHT SNOW IN DURING THE
AFTERNOON HOURS SOUTH OF A RAWLINS TO CHADRON LINE. THE NEW YEAR
WILL DAWN WITH COLDER TEMPERATURES PER PROGGED 1000-500 MB
THICKNESSES AND 700 MB TEMPERATURES NEAR -14 CELSIUS.
WEDNESDAY NIGHT...DRY PERIOD WITH LACK OF LOW AND MID LEVEL MOISTURE
AND LIFT...THOUGH EXPECT BREEZY TO WINDY CONDITIONS WEST OF
INTERSTATE 25 DUE TO PROGGED LOW AND MID LEVEL GRADIENTS.
THURSDAY...ANOTHER MUCH WEAKER POSITIVELY TILTED SHORTWAVE TROUGH
ALOFT PROGGED TO SLIDE SOUTHEAST TO THE WESTERN DAKOTAS...THOUGH
WITH NO APPRECIABLE WEATHER EFFECTS OVER OUR COUNTIES EXCEPT TO
REINFORCE THE SURFACE LEE TROUGH ALONG THE EASTERN SLOPES OF THE
ROCKIES. THUS EXPECT A DRY DAY WITH TYPICAL BREEZY TO WINDY
CONDITIONS PER PROGGED LOW AND MID LEVEL GRADIENTS.
THURSDAY NIGHT...CONTINUED DRY DUE TO LACK OF LOW AND MID LEVEL
MOISTURE. ANOTHER HIGH WIND EVENT LOOKS QUITE LIKELY FOR OUR WIND
PRONE LOCATIONS SUCH AS BORDEAUX...ARLINGTON...ELK MOUNTAIN AND
VEDAUWOO BASED ON PROGGED SURFACE THROUGH 700 MB GRADIENTS. DECENT
MIXING WILL MAKE FOR A RELATIVELY MILD NIGHT ALONG THE SPINE OF THE
LARAMIE RANGE AND INTERSTATE 25 CORRIDOR FROM WHEATLAND TO THE
COLORADO STATE LINE.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 245 PM MST TUE DEC 31 2013
ONE MORE MILD DAY ON FRIDAY BEFORE CHANGES ENSUE. MODELS IN GOOD
AGREEMENT INITIALLY...BRINGING NEXT UPPER TROF ACROSS THE REGION
SATURDAY WHICH SHOULD BRING SOME LIGHT SNOWS AS WELL AS COLDER
TEMPERATURES. DISAGREEMENTS THEN BEGIN SUNDAY INTO EARLY NEXT WEEK
WITH THE HANDLING OF THE NEXT ARCTIC SURGE DROPPING SOUTHEAST OUT
OF CANADA. GFS IS STRONGER AND SLOWER WITH THIS...PRODUCING A MORE
EXTENDED PERIOD OF VERY COLD CONDITIONS OVER THE CWA ESPECIALLY
THE PLAINS WHILE THE EC IS LESS BULLISH WITH THE COLDER AIR AND
BRINGS IT DOWN QUICKER AND IN SEPARATE SURGES. FOR NOW WILL LEAN
TOWARDS THE EC AS IT TENDS TO PERFORM BETTER WITH THESE SCENARIOS
BUT WILL HAVE TO GO COLDER IF IT TRENDS TOWARDS THE GFS. OTHERWISE
SOME LIGHT SNOWS SHOULD BE ASSOCIATED WITH THIS COLD AIR MASS...
MOSTLY OVER THE NORTHEAST PART OF THE CWA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY EVENING)
ISSUED AT 1040 PM MST TUE DEC 31 2013
LATEST RADAR SHOWING AREA OF SNOW DROPPING SOUTH LATE THIS
EVENING. CHADRON ALREADY IFR AND LATEST HRRR FORECAST SHOWING THIS
IFR AREA DROPPING SOUTH INTO THE SOUTHERN PANHANDLE AS THE MORNING
PROGRESSES. SNOW ALSO IMPACTING KRWL AND KLAR AROUND THE 09Z
TIME FRAME AND CONTINUING THROUGH 18Z.
&&
.FIRE WEATHER...
ISSUED AT 245 PM MST TUE DEC 31 2013
MINIMAL FIRE WEATHER ISSUES BASED ON PROJECTED HUMIDITIES.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY UNTIL 11 AM MST WEDNESDAY FOR WYZ112-114.
HIGH WIND WARNING UNTIL 3 AM MST WEDNESDAY FOR WYZ106-110-116-
117.
NE...NONE.
&&
$$
UPDATE...CLAYCOMB
SHORT TERM...RUBIN
LONG TERM...RE
AVIATION...CLAYCOMB
FIRE WEATHER...RUBIN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
658 AM MST WED JAN 1 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 443 AM MST WED JAN 1 2014
THE UPPER LEVEL TROF WILL GLANCE THROUGH NORTHERN AND EASTERLY
COLORADO TODAY SENDING A COLD FRONT THROUGH THE REGION. MOUNTAINS
AREAS WILL SEE AT LEAST A SLIGHT CHANCE FOR SNOW...WITH THE CENTRAL
MOUNTAINS PICKING UP SOME LIGHT ACCUMULATIONS DUE TO BETTER PROXIMITY
TO DYNAMICS THIS MORNING...AND CONTINUED NORTHWESTERLY OROGRAPHIC
FLOW INTO THIS EVENING. MODELS ARE GIVING AN ADDITIONAL 1 TO 3
INCHES OF ACCUMULATION FOR THAT AREA. STILL A VARIETY OF SOLUTIONS FOR
THE SOUTHEAST PLAINS AS FAR AS PRECIPITATION GOES WITH NAM12 KEEPING
ALL THE SNOW TO THE NORTH OF THE FORECAST AREA. GFS AND ECMWF OFFER
UP MORE WIDESPREAD PRECIPITATION...ALBEIT LIGHT...ACROSS THE
SOUTHEAST MOUNTAINS AND PLAINS TODAY. RAP13 AND HRRR SEEM TO OFFER
A CONSENSUS SOLUTION WITH LOCATIONS MAINLY ACROSS NORTHERN EL PASO
COUNTY OUT TOWARDS KIOWA COUNTY PICKING UP SOME LIGHT SNOW. HAVE
INTRODUCED SOME SCATTERED POPS FOR THESE AREAS...EVEN A BRIEF LIKELY
POP FOR THE NORTHEAST UPSLOPE FAVORED REGIONS OF TELLER AND NRN EL
PASO RIGHT AROUND 15Z. ANY ACCUMULATIONS WILL PROBABLY REMAIN UNDER
AN INCH.
THE ASSOCIATED COLD FRONT WILL DROP THROUGH THE REGION EARLY THIS
MORNING BRINGING SOME GUSTY NORTH WINDS TO ALL OF THE SOUTHEAST
PLAINS...ALONG WITH COLDER TEMPERATURES. CAA WILL BE OFFSET SOME BY
THE GUSTY WINDS AND MIXING...SO HIGHS WILL PROBABLY TOP OUT AROUND
NOON...THEN STAY STEADY BEFORE FALLING AGAIN TOWARDS EVENING. HAVE
KEPT HIGHS IN THE 40S FOR THE PLAINS. MOUNTAIN AREAS WILL LARGELY
TOP OUT IN THE 20S AND LOWER 30S...THOUGH HIGHER PEAKS WILL ONLY
MAKE THE TEENS. OTHER CONUNDRUM WILL BE TEMPERATURES FOR ALAMOSA.
ON THE ONE HAND...THE UPPER TROF HAS THE POTENTIAL TO BRING SOME
MIXING TO THE SAN LUIS VALLEY ALLOWING TEMPERATURES TO WARM INTO THE
20S. ON THE OTHER HAND IF INVERSIONS ARE TOO STRONG THEN HIGHS
COULD REMAIN IN THE TEENS. HAVE GONE A LITTLE WARMER THAN YESTERDAY
ESPECIALLY ALONG VALLEY EDGES WHERE MIXING IS MORE LIKELY TO OCCUR.
TONIGHT...DRY AIR WILL SPREAD IN BEHIND THE DEPARTING SYSTEM
ALLOWING FOR EFFICIENT RADIATIONAL COOLING. MIN TEMPERATURES IN
KALS COULD APPROACH -20 BASED ON MET GUIDANCE...WHICH DOES NOT SEEM
TOO UNREASONABLE...THOUGH SPLIT THE DIFFERENCE BETWEEN MET AND
SLIGHTLY WARMER MAV GUIDANCE FOR NOW. ELSEWHERE...TEENS LOOK LIKELY
FOR THE LOWER ARKANSAS RIVER VALLEY WHILE LEE TROFING AND SOME
WESTERLY DRAINAGE WINDS SHOULD KEEP LOWS IN THE 20S ALONG THE LOWER
SLOPES OF THE SE MTS/ADJACENT PLAINS WEST OF I-25. GIVEN HOW DRY
THE ATMOS IS ABOVE THE SURFACE WILL REFRAIN FROM INTRODUCING FOG
INTO THE SAN LUIS VALLEY AS PROBABILITY LOOKS LOW AT THIS POINT. -KT
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 443 AM MST WED JAN 1 2014
.THURSDAY AND FRIDAY...FLOW ALOFT BECOMES MORE WESTERLY AHEAD OF
THE NEXT DISTURBANCE APPROACHING FROM THE NORTHWEST. TEMPERATURES
ALOFT WARM TO AROUND +2C BY FRIDAY. WITH LEE TROUGH DEVELOPING
OVER THE PLAINS...ANTICIPATE TEMPERATURES APPROACHING 60F ON THE
PLAINS ON FRIDAY. OVER THE MOUNTAINS AND HIGH VALLEYS...IT WILL BE DRY
WITH SOME LIGHT SNOW POSSIBLY REACHING THE MOUNTAINS OF LAKE
COUNTY BY LATE FRIDAY. TEMPERATURES WILL BE MILD...EXCEPT FOR THE
SAN LUIS VALLEY WHERE COLD AIR WILL REMAIN TRAPPED.
.SATURDAY THROUGH MONDAY...ONE DISTURBANCE PASSES OVER REGION ON
SATURDAY WITH A SECONDARY DISTURBANCE PASSING MOSTLY TO THE NORTHEAST
OF THE REGION ON MONDAY. THERE WILL BE A COLD ASSOCIATED WITH EACH
DISTURBANCE. THE REGION WILL BE ON THE WESTERN FRINGES OF SOME
ARCTIC AIR...AND THE MAIN CHALLENGE IS THE AMOUNT OF COOLING
BEHIND THE FRONT. MODELS HAVE GENERALLY BEEN TRENDING TOWARDS
HAVING THE CORE OF THE COLD AIR STAYING FURTHER TO THE NORTHEAST
OF THE REGION...AND ONLY WENT WITH MODEST COOLING BEHIND THE
FRONTS. IF THE COLD AIR MOVES SLIGHTLY FURTHER TO THE WEST...THEN
HIGHS COLD EASILY BE 10F COOLER THAN WHAT IS CURRENTLY IN THE
GRIDS. A POCKET OF COLD AIR ALOFT WILL ACCOMPANY THE FRONTAL
PASSAGE ON SATURDAY. WITH THE WEAK STABILITY...THERE IS A CHANCE
FOR THE LIGHT SNOW BEHIND THE COLD FRONT OVER THE PLAINS AND
EASTERN MOUNTAINS. OVER THE REMAINING MOUNTAINS AND HIGH
VALLEYS...LIGHT SNOW WILL MOSTLY LIKELY ON SATURDAY WITH THE BEST
CHANCES IN MOUNTAINS OF LAKE AND CHAFFEE COUNTIES. ANTICIPATE AMOUNTS
WILL STAY BELOW ADVISORY CRITERIA. THE DISTURBANCE ON MONDAY WILL
BE FURTHER TO THE NORTHEAST RESULTING IN LESSER CHANCES FOR SNOW.
THE SAN LUIS VALLEY MAY MIX OUT SATURDAY...BUT WITH COLDER AIR
ALOFT TEMPERATURES WILL NOT INCREASE MUCH.
.TUESDAY...SURFACE HIGH PRESSURE WILL MOVE EAST OF THE REGION WITH
A REBOUND IN TEMPERATURE ANTICIPATED. WITH A SHORTWAVE RIDGE OVER
THE REGION...CHANCES FOR MOUNTAIN SNOW ARE SMALL. --PGW--
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 656 AM MST WED JAN 1 2014
MID CLOUDS ARE HAMPERING FOG FORMATION AT KALS THIS MORNING SO
HAVE UPDATED TAF TO REMOVE FOG. PASSING SHOWERS AT KCOS HAVE
PROMPTED INCLUSION OF A VFR TEMPO GROUP FOR -SHSN. LITTLE TO NO
ACCUMULATION IS EXPECTED AT THE TERMINAL. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KT
LONG TERM...PGW
AVIATION...KT
AREA FORECAST DISCUSSION
NWS PUEBLO CO
444 AM MST WED JAN 1 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 443 AM MST WED JAN 1 2014
THE UPPER LEVEL TROF WILL GLANCE THROUGH NORTHERN AND EASTERLY
COLORADO TODAY SENDING A COLD FRONT THROUGH THE REGION. MOUNTAINS
AREAS WILL SEE AT LEAST A SLIGHT CHANCE FOR SNOW...WITH THE CENTRAL
MOUNTAINS PICKING UP SOME LIGHT ACCUMULATIONS DUE TO BETTER PROXIMITY
TO DYNAMICS THIS MORNING...AND CONTINUED NORTHWESTERLY OROGRAPHIC
FLOW INTO THIS EVENING. MODELS ARE GIVING AN ADDITIONAL 1 TO 3
INCHES OF ACCUMULATION FOR THAT AREA. STILL A VARIETY OF SOLUTIONS FOR
THE SOUTHEAST PLAINS AS FAR AS PRECIPITATION GOES WITH NAM12 KEEPING
ALL THE SNOW TO THE NORTH OF THE FORECAST AREA. GFS AND ECMWF OFFER
UP MORE WIDESPREAD PRECIPITATION...ALBEIT LIGHT...ACROSS THE
SOUTHEAST MOUNTAINS AND PLAINS TODAY. RAP13 AND HRRR SEEM TO OFFER
A CONSENSUS SOLUTION WITH LOCATIONS MAINLY ACROSS NORTHERN EL PASO
COUNTY OUT TOWARDS KIOWA COUNTY PICKING UP SOME LIGHT SNOW. HAVE
INTRODUCED SOME SCATTERED POPS FOR THESE AREAS...EVEN A BRIEF LIKELY
POP FOR THE NORTHEAST UPSLOPE FAVORED REGIONS OF TELLER AND NRN EL
PASO RIGHT AROUND 15Z. ANY ACCUMULATIONS WILL PROBABLY REMAIN UNDER
AN INCH.
THE ASSOCIATED COLD FRONT WILL DROP THROUGH THE REGION EARLY THIS
MORNING BRINGING SOME GUSTY NORTH WINDS TO ALL OF THE SOUTHEAST
PLAINS...ALONG WITH COLDER TEMPERATURES. CAA WILL BE OFFSET SOME BY
THE GUSTY WINDS AND MIXING...SO HIGHS WILL PROBABLY TOP OUT AROUND
NOON...THEN STAY STEADY BEFORE FALLING AGAIN TOWARDS EVENING. HAVE
KEPT HIGHS IN THE 40S FOR THE PLAINS. MOUNTAIN AREAS WILL LARGELY
TOP OUT IN THE 20S AND LOWER 30S...THOUGH HIGHER PEAKS WILL ONLY
MAKE THE TEENS. OTHER CONUNDRUM WILL BE TEMPERATURES FOR ALAMOSA.
ON THE ONE HAND...THE UPPER TROF HAS THE POTENTIAL TO BRING SOME
MIXING TO THE SAN LUIS VALLEY ALLOWING TEMPERATURES TO WARM INTO THE
20S. ON THE OTHER HAND IF INVERSIONS ARE TOO STRONG THEN HIGHS
COULD REMAIN IN THE TEENS. HAVE GONE A LITTLE WARMER THAN YESTERDAY
ESPECIALLY ALONG VALLEY EDGES WHERE MIXING IS MORE LIKELY TO OCCUR.
TONIGHT...DRY AIR WILL SPREAD IN BEHIND THE DEPARTING SYSTEM
ALLOWING FOR EFFICIENT RADIATIONAL COOLING. MIN TEMPERATURES IN
KALS COULD APPROACH -20 BASED ON MET GUIDANCE...WHICH DOES NOT SEEM
TOO UNREASONABLE...THOUGH SPLIT THE DIFFERENCE BETWEEN MET AND
SLIGHTLY WARMER MAV GUIDANCE FOR NOW. ELSEWHERE...TEENS LOOK LIKELY
FOR THE LOWER ARKANSAS RIVER VALLEY WHILE LEE TROFING AND SOME
WESTERLY DRAINAGE WINDS SHOULD KEEP LOWS IN THE 20S ALONG THE LOWER
SLOPES OF THE SE MTS/ADJACENT PLAINS WEST OF I-25. GIVEN HOW DRY
THE ATMOS IS ABOVE THE SURFACE WILL REFRAIN FROM INTRODUCING FOG
INTO THE SAN LUIS VALLEY AS PROBABILITY LOOKS LOW AT THIS POINT. -KT
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 443 AM MST WED JAN 1 2014
.THURSDAY AND FRIDAY...FLOW ALOFT BECOMES MORE WESTERLY AHEAD OF
THE NEXT DISTURBANCE APPROACHING FROM THE NORTHWEST. TEMPERATURES
ALOFT WARM TO AROUND +2C BY FRIDAY. WITH LEE TROUGH DEVELOPING
OVER THE PLAINS...ANTICIPATE TEMPERATURES APPROACHING 60F ON THE
PLAINS ON FRIDAY. OVER THE MOUNTAINS AND HIGH VALLEYS...IT WILL BE DRY
WITH SOME LIGHT SNOW POSSIBLY REACHING THE MOUNTAINS OF LAKE
COUNTY BY LATE FRIDAY. TEMPERATURES WILL BE MILD...EXCEPT FOR THE
SAN LUIS VALLEY WHERE COLD AIR WILL REMAIN TRAPPED.
.SATURDAY THROUGH MONDAY...ONE DISTURBANCE PASSES OVER REGION ON
SATURDAY WITH A SECONDARY DISTURBANCE PASSING MOSTLY TO THE NORTHEAST
OF THE REGION ON MONDAY. THERE WILL BE A COLD ASSOCIATED WITH EACH
DISTURBANCE. THE REGION WILL BE ON THE WESTERN FRINGES OF SOME
ARCTIC AIR...AND THE MAIN CHALLENGE IS THE AMOUNT OF COOLING
BEHIND THE FRONT. MODELS HAVE GENERALLY BEEN TRENDING TOWARDS
HAVING THE CORE OF THE COLD AIR STAYING FURTHER TO THE NORTHEAST
OF THE REGION...AND ONLY WENT WITH MODEST COOLING BEHIND THE
FRONTS. IF THE COLD AIR MOVES SLIGHTLY FURTHER TO THE WEST...THEN
HIGHS COLD EASILY BE 10F COOLER THAN WHAT IS CURRENTLY IN THE
GRIDS. A POCKET OF COLD AIR ALOFT WILL ACCOMPANY THE FRONTAL
PASSAGE ON SATURDAY. WITH THE WEAK STABILITY...THERE IS A CHANCE
FOR THE LIGHT SNOW BEHIND THE COLD FRONT OVER THE PLAINS AND
EASTERN MOUNTAINS. OVER THE REMAINING MOUNTAINS AND HIGH
VALLEYS...LIGHT SNOW WILL MOSTLY LIKELY ON SATURDAY WITH THE BEST
CHANCES IN MOUNTAINS OF LAKE AND CHAFFEE COUNTIES. ANTICIPATE AMOUNTS
WILL STAY BELOW ADVISORY CRITERIA. THE DISTURBANCE ON MONDAY WILL
BE FURTHER TO THE NORTHEAST RESULTING IN LESSER CHANCES FOR SNOW.
THE SAN LUIS VALLEY MAY MIX OUT SATURDAY...BUT WITH COLDER AIR
ALOFT TEMPERATURES WILL NOT INCREASE MUCH.
.TUESDAY...SURFACE HIGH PRESSURE WILL MOVE EAST OF THE REGION WITH
A REBOUND IN TEMPERATURE ANTICIPATED. WITH A SHORTWAVE RIDGE OVER
THE REGION...CHANCES FOR MOUNTAIN SNOW ARE SMALL. --PGW--
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 443 AM MST WED JAN 1 2014
GUSTY NORTH WINDS WILL SPREAD ACROSS THE SOUTHEAST PLAINS THIS
MORNING BEHIND A COLD FRONT WITH GUSTS TO 25 TO 30 KTS POSSIBLE.
THROUGH MID DAY AT BOTH THE KPUB AT KCOS TAF SITES. STRONGEST GUSTS WILL
BE IMMEDIATELY BEHIND THE FRONTAL PASSAGE THIS MORNING. SOME VFR
CIGS WITH -SHSN WILL SPREAD ACROSS NORTHERN SECTIONS OF THE
SOUTHEAST PLAINS THIS MORNING...THOUGH BEST CHANCE WILL BE NORTH OF
THE KCOS TERMINAL. IF LIGHT SNOW DOES AFFECT THE KCOS TERMINAL...
ACCUMULATIONS SHOULD REMAIN LESS THAN AN INCH. -SHSN WILL BE EVEN
LESS LIKELY FOR KPUB SO WILL NOT INCLUDE MENTION IN THE TAF. KALS
STILL HAS A SHOT FOR SEEING SOME PATCHY GROUND FOG BETWEEN 11Z AND
16Z...THOUGH IT SHOULD NOT BE AS WIDESPREAD OR AS PERSISTENT AS PAST
FEW DAYS. MEANWHILE...CENTRAL MOUNTAINS AND PIKES PEAK REGION WILL
SEE SOME SCATTERED -SHSN TODAY WITH IFR TO LIFR CIGS/VIS AND MTN
OBSCURATIONS AT TIMES.
CLEARING CONDITIONS EXPECTED THIS EVENING WITH RESIDUAL SNOW SHOWERS
ACROSS THE CENTRAL MOUNTAINS COMING TO AN END AROUND 09Z. FOG AT
KALS LOOKS LESS LIKELY TONIGHT DUE TO VERY DRY AIR ALOFT. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KT
LONG TERM...PGW
AVIATION...KT
AREA FORECAST DISCUSSION
NWS ALBANY NY
649 AM EST WED JAN 1 2014
.SYNOPSIS...
AN APPROACHING STORM SYSTEM TODAY WILL REFORM OFF THE
EASTERN SEABOARD ON THURSDAY...ALLOWING FOR A PROLONGED PERIOD OF
SNOW ACROSS THE REGION FOR TONIGHT THROUGH FRIDAY MORNING. VERY COLD
AIR WILL ACCOMPANY THIS SNOW...ESPECIALLY ACROSS NORTHERN AND HIGH
TERRAIN PORTIONS OF THE REGION. DRY...BUT CONTINUED COLD WEATHER
WILL BE IN PLACE ON SATURDAY...BEFORE ANOTHER STORM THREATENS THE
REGION FOR SUNDAY INTO MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 649 AM EST...WITH HIGH PRESSURE SITUATED SOUTH OF THE AREA
OVER THE MID ATLANTIC STATES...SKIES ARE MAINLY CLEAR OVER MUCH OF
THE REGION THIS MORNING...ALONG WITH COLD TEMPERATURES. A BAND OF
LAKE EFFECT SNOW CONTINUES OFF LAKE ONTARIO...ALTHOUGH THE BULK OF
THIS ACTIVITY IS OCCURRING WELL WEST OF OUR AREA. SOME STRATOCU
CLOUDS FROM THIS LAKE EFFECT ACTIVITY ARE OVER THE WESTERN
ADIRONDACKS...MOHAWK VALLEY AND CATSKILLS...ALONG WITH SOME LIGHT
SNOW SHOWERS AND FLURRIES ACROSS PARTS OF THE THESE AREAS AS WELL.
THE LATEST 09Z HRRR SHOWS SOME FLURRIES MAY CONTINUE TO IMPACT THE
MOHAWK VALLEY OVER THE NEXT FEW HOURS...BUT ANY ACCUMULATING SNOW
WILL REMAIN WELL WEST OF THE REGION CLOSER TO THE LAKE SHORE. BY
LATER THIS MORNING...LAKE EFFECT ACTIVITY WILL START TO WIND DOWN
AS INVERSION HEIGHTS LOWER...AS A STRONG AREA OF ARCTIC HIGH
PRESSURE MOVES ACROSS EASTERN ONTARIO.
AN UPPER LEVEL TROUGH WILL CONTINUE TO SHARPEN OVER THE
CENTRAL PLAINS TODAY AS IT MOVES EASTWARD TOWARDS THE OHIO
VALLEY. SURFACE LOW PRESSURE WILL START TO DEVELOP OVER THE
MISSISSIPPI VALLEY AND A SURFACE BOUNDARY WILL EXTEND ACROSS THE
OHIO VALLEY TOWARDS WESTERN PA.
BROAD SW FLOW OVER THIS FRONTAL BOUNDARY WILL ALLOW FOR
OVERRUNNING SNOWFALL TO DEVELOP ACROSS WESTERN AND CENTRAL NY TODAY.
MOST OF THE DAY LOOKS DRY ACROSS OUR REGION...BUT THIS SNOW WILL
START TO SPREAD TOWARDS OUR WESTERN ZONES BY LATE THIS AFTN AND
EARLY THIS EVENING. AS A RESULT...CLOUDS WILL INCREASE TODAY FROM
WEST TO EAST. WHILE THE DAY WILL START OFF WITH A PARTIAL TO
MOSTLY SUNNY SKY...SKIES WILL BE MOSTLY CLOUDY BY THIS AFTN.
AFTER A VERY COLD START...MAX TEMPS THIS AFTN WILL RANGE FROM THE
TEENS OVER THE ADIRONDACKS TO THE 20S ACROSS THE REMAINDER OF THE
AREA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
WINTER STORM WATCHES HAVE BEEN ISSUED FOR THE ENTIRE AREA OUTSIDE
THE ADIRONDACKS/LAKE GEORGE/SARATOGA AREAS...FOR TONIGHT THROUGH
FRIDAY MORNING.
...A PROLONGED PERIOD OF SNOWFALL ACROSS OUR REGION WILL ALLOW FOR
A MODERATE TO HEAVY SNOWFALL FOR MUCH OF THE AREA...
WITH THE SURFACE BOUNDARY SITUATED SOUTH OF THE AREA...ISENTROPIC
LIFT/WARM AIR ADVECTION WILL ALLOW FOR LIGHT SNOW TONIGHT INTO
THURSDAY. AT THE SAME TIME...AN AREA OF SURFACE LOW PRESSURE WILL
DEVELOP OFF THE EASTERN SEABOARD ON THURSDAY...AND MOVE NORTHEAST
FOR THURSDAY NIGHT. THIS STORM WILL BE FAIRLY FAR OFF THE
COAST...BUT SHOULD STILL ALLOW FOR SOME ATLANTIC MOISTURE TO GET
THROWN BACK INTO OUR AREA. WITH THE STRONG UPPER TROUGH MOVING
TOWARDS OUR AREA FOR THURSDAY NIGHT...DEFORMATION WILL ALLOW FOR
ADDITIONAL SNOWFALL...BEFORE SNOWFALL TAPERS OFF EARLY FRIDAY
MORNING. SOME BANDING OF SNOWFALL COULD OCCUR ACROSS FAR EASTERN
PARTS OF OUR AREA THURSDAY NIGHT AS THE LOW PRESSURE STARTS TO
RAPIDLY DEEPEN. WHILE SNOW RATES AREN/T EXPECTED TO BE EXTREME AT
ANY POINT DURING THIS STORM...THE PROLONGED NATURE OF THE EVENT
WILL ALLOW FOR A SIGNIFICANT IMPACT ACROSS OUR AREA.
SNOW TO LIQUID RATIOS WILL BE VERY HIGH...GENERALLY 15:1 OR
HIGHER...AS STRONG OMEGA WILL BE MOVING THROUGH THE DENDRITIC
GROWTH ZONES /WHICH WILL BE VERY LOW TO THE GROUND DUE TO THE COLD
TEMPS IN PLACE/. THIS WILL ALLOW FOR A LIGHT AND FLUFFY SNOW TO
ADDS UP VERY EASILY TO OCCUR.
THE MAIN FORECAST QUESTION IS HOW MUCH QPF OCCURS. THE 00Z AND 06Z
NAM HAVE BEEN PERSISTENT IN SHOWING MUCH MORE QPF THAN THE OTHER
MODELS...WITH OVER 1.00 INCH LIQUID OVER CENTRAL/SOUTHERN PORTIONS OF
THE AREA. MEANWHILE..THE 00Z GFS/ECMWF/GGEM AND GEFS MEAN ARE
SHOWING AROUND 0.60 INCHES ACROSS MUCH OF THE AREA GIVE OR TAKE. THE
03Z SREF MEAN FOR KALB IS 0.84 INCHES. WE WILL KEEP THE FORECAST CLOSE
TO MODEL CONSENSUS FOR NOW...BUT CONTINUE TO MONITOR MODEL
TRENDS...AS THE NAM CAN SOMETIMES PICK UP ON MESOSCALE ASPECTS
THAT THE GLOBAL MODELS DO NOT. EVEN WITH THESE LESSER AMOUNTS...IT
STILL LOOKS LIKE WE WILL REACH WINTER STORM WARNING CRITERIA /9
INCHES IN 24 HOURS/ ACROSS CENTRAL/SOUTHERN AREAS DUE TO THE
EXPECTED HIGH RATIOS...WHICH IS WHY THE WATCH HAS BEEN ISSUED FOR
THESE AREAS. FURTHER NORTH ACROSS THE ADKS/LAKE GEORGE/SARATOGA
AREA...SNOWFALL AMOUNTS WILL BE SLIGHTLY LESS...BUT A PLOWABLE
SNOW IS STILL EXPECTED.
TEMPS WILL BE QUITE COLD DURING THE ENTIRE EVENT. AFTER TEMPS
REACH THE THEIR HIGH ON WEDNESDAY...THEY WILL BASICALLY HOLD
STEADY/SLOWLY FALL FOR WED NIGHT THROUGH THURSDAY INTO THURSDAY
NIGHT. TEMPS WILL BE IN THE TEENS TONIGHT/THURSDAY...AND FALL INTO
THE SINGLE DIGITS TO SINGLE DIGITS BELOW ZERO FOR THURSDAY NIGHT.
OVER THE ADIRONDACKS...TEMPS WILL FALL ZERO TO MINUS 20 FOR
THURSDAY NIGHT. WITH A N-NE WIND IN PLACE...THIS WILL ALLOW FOR VERY
COLD WIND CHILL VALUES OVER THE ADIRONDACKS. A WIND CHILL WATCH
HAS BEEN ISSUED FOR THE POTENTIAL FOR WIND CHILL VALUES OF -30 TO
-40 BELOW ZERO FOR LATE THURSDAY NIGHT INTO FRIDAY MORNING.
ELSEWHERE...WIND CHILL VALUES MAY REACH ADVISORY CRITERIA..AND
THIS WILL BE HIGHLIGHTED IN THE HWO.
ANY LINGERING SNOW SHOWERS WILL BE TAPERING OFF FRIDAY
MORNING...AND SKIES LOOK TO BECOME MOSTLY SUNNY BY FRI AFTN.
DESPITE THE RETURN OF THE SUN...IT WON/T DO ANYTHING FOR
TEMPS...WITH DAYTIME HIGHS ONLY IN THE SINGLE DIGITS. SOME AREAS
IN THE ADIRONDACKS AND UPPER MOHAWK VALLEY MAY NOT EVEN REACH ZERO
FOR HIGHS ON FRIDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
ANOTHER STORM SYSTEM FOR SUNDAY NIGHT INTO MONDAY.
WE WILL START OUT THE PERIOD WITH RIDGING BUILDING IN ALOFT WITH THE
SURFACE HIGH CRESTING OVER THE REGION LATE FRIDAY NIGHT INTO
SATURDAY MORNING. ALONG WITH A FRESH SNOW THIS WILL SET THE STAGE
FOR ANOTHER COLD NIGHT ACROSS THE REGION WITH LOWS EXPECTED TO BE
BELOW ZERO ACROSS THE ENTIRE FORECAST AREA.
THE SURFACE HIGH IS EXPECTED TO SHIFT EASTWARD OFF THE COAST
SATURDAY. DESPITE A SOUTHERLY FLOW DEVELOP IT WILL BE COLD WITH
THE FRESH SNOWPACK ON THE GROUND WITH HIGHS ONLY IN THE TEENS.
BROAD SOUTHWESTERLY FLOW WILL DEVELOP ACROSS THE EASTERN UNITED
STATES AS A POTENT SHORT WAVE MOVES INTO OVER PACIFIC NORTHWEST
DIGGING A DEEP TROUGH OVER THE CENTRAL CONUS OVER THE WEEKEND. IN
ADDITION...AN UPPER LEVEL LOW WILL STRENGTHEN AS IT MOVES SOUTHWARD
ACROSS CENTRAL CANADA TOWARDS THE GREAT LAKES REGION. PIECES OF
ENERGY ARE EXPECTED TO ROTATE ABOUT THIS LOW AS IT MOVES EASTWARD
ACROSS EASTERN CANADA AS WE HEAD INTO NEXT WEEK.
THERE IS GOOD AGREEMENT AMONGST THE MODEL GUIDANCE THAT THE LOW
PRESSURE SYSTEM ASSOCIATED WITH THE UPPER LOW WILL REMAIN WELL TO
OUR NORTHWEST. HOWEVER THERE ARE DIFFERENCES AND THE FORECAST GETS
COMPLICATED AS THE POTENT SHORT WAVE ROTATES THROUGH THE BASE OF THE
DEEP TROUGH OVER THE TENNESSEE VALLEY AND SPINNING UP A SURFACE LOW.
THE ECMWF CONTINUES TO DEVELOP AND TRACK THE LOW FARTHER TO THE WEST
PASSING THE LOW OVER THE OHIO VALLEY DUE TO THE POSITION OF THE
UPPER LOW BEING FARTHER TO WEST. WHILE THE GFS BRINGS THE LOW ACROSS
NEW YORK AND NEW ENGLAND SUNDAY NIGHT INTO MONDAY. THE OPERATIONAL
GFS IS ON THE WEST SIDE OF THE GFSENSEMBLE TRACKS. THE EXACT TRACK
OF THE LOW WILL DETERMINE THE THERMAL PROFILE AND THEREFORE P-TYPES.
HAVE USED GUIDANCE FROM THE WEATHER PREDICTION CENTER WHICH TOOK A
COMPROMISE TRACK THEN LEANED TOWARD THE GFS THE COLDER SCENARIO.
BASED ON THIS HAVE FORECASTED PRECIPITATION TO OVERSPREAD THE AREA
SUNDAY NIGHT THEN CONTINUE INTO MONDAY. WOULD EXPECT SNOW SUNDAY
NIGHT WITH A CHANGEOVER TO RAIN LIKELY ACROSS THE HUDSON VALLEY AND
LITCHFIELD ON MONDAY WITH RAIN POSSIBLE FARTHER NORTHWARD.
UNCERTAINTY IS THIS FORECAST IS HIGH AT THIS TIME.
FOLLOWING THIS STORM SYSTEM ANOTHER ROUND OF VERY COLD ARCTIC AIR IS
EXPECTED WITH DAYTIME HIGHS SIMILAR TO WHAT OUR NORMAL LOWS SHOULD
BE.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS ARE EXPECTED THROUGH THE EVENING WITH CONDITIONS THEN
DETERIORATING OVERNIGHT AS LIGHT SNOW OVERSPREADS THE AREA. IN THE
MEANTIME LAKE EFFECT CLOUDS WILL CONTINUE TO EXTEND INTO THE AREA
MUCH OF THE DAY. CLOUDS ASSOCIATED WITH THE APPROACHING LOW PRESSURE
SYSTEM WILL BEGIN TO OVERSPREAD THE AREA THIS AFTERNOON...THEN LOWER
AND THICKEN TONIGHT AS THE LIGHT OVERRUNNING SNOW MOVES IN.
WESTERLY WINDS WILL PICK UP IN SPEED A BIT WITH GUSTS AT KALB AND
KPSF. BY LATE AFTERNOON INTO THE EVENING WINDS WILL WEAKEN AND SHIFT
TOWARD THE NORTH.
OUTLOOK...
THU NIGHT: HIGH OPERATIONAL IMPACT. DEFINITE SN.
FRI: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
FRI NIGHT-SAT NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUN: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
&&
.HYDROLOGY...
NO WIDESPREAD HYDROLOGIC PROBLEMS ARE EXPECTED OVER THE NEXT FIVE DAYS.
A STORM SYSTEM WILL BRING SNOW TO THE REGION TONIGHT THROUGH
FRIDAY MORNING. VERY COLD TEMPERATURES ARE EXPECTED LATE THIS
WEEK...WHICH WILL CONTINUE TO ALLOW RIVER AND LAKE ICE TO FORM AND
THICKEN.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WINTER STORM WATCH FROM THIS EVENING THROUGH FRIDAY MORNING
FOR CTZ001-013.
NY...WINTER STORM WATCH FROM THIS EVENING THROUGH FRIDAY MORNING
FOR NYZ038>040-047>054-058>061-063>066.
WIND CHILL WATCH FROM THURSDAY EVENING THROUGH FRIDAY MORNING
FOR NYZ032-033-042.
MA...WINTER STORM WATCH FROM THIS EVENING THROUGH FRIDAY MORNING
FOR MAZ001-025.
VT...WINTER STORM WATCH FROM THIS EVENING THROUGH FRIDAY MORNING
FOR VTZ013>015.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS
SHORT TERM...FRUGIS
LONG TERM...IAA
AVIATION...IAA
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1033 AM EST WED JAN 1 2014
.SYNOPSIS...
HIGH PRESSURE OVER THE DELMARVA SHIFTS OFFSHORE THIS AFTERNOON.
AN ARCTIC COLD FRONT STRETCHED FROM NORTHERN NEW ENGLAND TO TORONTO
AND INDIANAPOLIS WILL SETTLE SOUTHWARD TONIGHT. TWO LOW PRESSURE
SYSTEMS WILL DEVELOP BY THURSDAY, ONE ACROSS THE APPALACHIANS AND
A SECONDARY LOW OFF OF THE CAROLINA COAST. THESE WILL MERGE INTO
ONE LOW OFFSHORE ON FRIDAY AND INTENSIFY AS IT MOVES AWAY FROM OUR
REGION. HIGH PRESSURE WILL THEN BUILD IN FOR MOST OF THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
VARIABLE MOSTLY HIGH CLOUDS TODAY AND SEASONABLE TEMPS. ENJOY THIS
RELATIVE WARMTH!
THE 12Z HRRR AND NAM ARE BOTH FCSTG MEASURABLE SNOW TO MOVE INTO
NORTHERN MONROE AND NORTHERN SUSSEX COUNTIES THIS AFTERNOON (20-23Z)
IN THE WARM AIR ADVECTION AHEAD OF THE SWD MOVING ARCTIC BOUNDARY.
HALF AN INCH OR SO IS POSSIBLE LATE THIS AFTERNOON THERE. THE 12Z
RAP HAS TEMPORARILY BACKED OFF THIS POSSIBILITY. RADAR AT 15Z AND
ON-GOING LIGHT SNOW KIPT WWD HAS CONVINCED ME TO MAKE THE ADJUSTMENT.
POPS WERE RAISED TO 40-50 PCT IN THOSE TWO COUNTIES AND THE 0-12 HR
GRAPHIC NOW HAS 0.3" THERE.
OTRW THE 330 AM FCST WAS BASICALLY UNCHANGED IN THE 930AM AND 1017
AM ESTF UPDATES WITH THE STANDARD MINOR ADJUSTMENTS FOR REALITY
TEMPS/SKYCOVER.
TONIGHT...THE SPC WRF AND SOME OTHER MODELS ARE BREAKING OUT PCPN
FROM COASTAL NNJ THROUGH NW NJ. THIS SHALLOW WAA AT THE TOP OF THE
MOISTENING BOUNDARY LAYER SHOWS WEAK 3MB/SEC UVM PULSES NEAR 4000
FT. THIS COULD HAPPEN AS SNOW GRAINS OR LIGHT SNOW AND WILL
REEVALUATE FOR THE 330 PM PACKAGE.
&&
.SHORT TERM /THURSDAY/...
WE SAW THE SWD SHIFTED AND DRIER 12Z/1 NAM PUTTING A LITTLE LESS
EMPHASIS ON THE WESTWARD OF THE TWO SFC LOWS E OF THE MID ATLC
COAST.
THE 00Z/1 CYCLES WERE HIGHLY DIVERGENT ON THE UPCOMING EVENT WITH
THE ECMWF AND GFS QPF ABOUT 30 PCT OF THE NAM WHICH WAS MODELING
MUCH MORE EMPHASIS ON THE TRAILING SFC LOW NEAR THE COAST INSTEAD
OF THE PROBABLE PRIMARY FURTHER EAST OFF THE MID ATLC COAST....NEAR
38/70 BY DAYS END. THERE WILL BE TREMENDOUS CYCLONIC CURVATURE
LATE THU AFTN AND THE ARCTIC BOUNDARY SINKING SWD WILL PROVIDE
FURTHER LIFT IN THE I80 REGION NWD AS THE ARCTIC AIR BEGINS ITS
SWD INTRUSION.
ALL THE 00Z/1 CYCLE MODELS AS WELL AS THE 12Z/1 NAM HAVE A DRY WEDGE
BETWEEN ROUGHLY 800-650 MB THURSDAY MORNING/MIDDAY.
SO THE DAYTIME EVOLUTION IS STILL MUCH IN DOUBT THO THE SREF IMPLIES
1-3" OF NEW SNOW ACCUMULATION BETWEEN DAYBREAK THU AND SUNSET THU
I80 REGION OR NORTH OF THAT ACROSS NORTHERN MONROE AND NORTHERN
SUSSEX COUNTIES IN NJ. ELSEWHERE...ESPECIALLY S OF I78...ABOVE
FREEZING TEMPS AND LITTLE GOING ON DURING THE DAY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
OVERVIEW...THE PERIOD BEGINS WITH THE POLAR/ARCTIC JET INDUCING LOW
PRESSURE OVER THE CENTRAL APPALACHIANS WHILE A TON OF MOISTURE POOLS
NEAR A FRONT, A SURFACE LOW, AND THE SOUTHERN STREAM JET ACROSS THE
SOUTHEASTERN STATES. ON THURSDAY NIGHT, THE TWO LOWS BEGIN TO PHASE
OFFSHORE. COME FRIDAY, THE MERGED LOW DEEPENS WELL OFFSHORE. SURFACE
HIGH PRESSURE WITH A MID-LEVEL ZONAL FLOW SETS UP ON FRIDAY NIGHT.
THE HIGH DRIFTS OFFSHORE SATURDAY AND SATURDAY NIGHT OFFERING A
BRIEF RETURN FLOW. A COLD FRONT WILL APPROACH THE REGION, FROM THE
WEST, ON SUNDAY BEFORE MOVING THROUGH ON SUNDAY NIGHT, ALONG WITH A
WAVE OF LOW PRESSURE. THE REGION COULD EXPERIENCE SOME BREEZY
CONDITIONS ON MONDAY WITH LOW PRESSURE TO OUR EAST AND A HIGH TO OUR
WEST. HIGH PRESSURE WILL BUILD FURTHER EAST ON MONDAY NIGHT AND
TUESDAY.
TEMPERATURES...BELOW/WELL BELOW NORMAL THURSDAY NIGHT THROUGH
SATURDAY. ABOUT NORMAL SUNDAY AND MONDAY. BELOW/WELL BELOW NORMAL
ONCE AGAIN ON TUESDAY.
BITTERLY COLD TEMPERATURES ARE EXPECTED THURSDAY NIGHT/FRIDAY
MORNING AND AGAIN FRIDAY NIGHT/SATURDAY MORNING WITH THE LATTER DAY
THE COLDER OF THE TWO. THE LEHIGH VALLEY AND NORTHWESTERN NEW JERSEY
COULD SEE SUB-ZERO TEMPERATURE FRIDAY NIGHT AND SATURDAY MORNING
WITH SINGLE DIGITS JUST ABOUT EVERYWHERE ELSE.
WIND WILL BE A SIGNIFICANT FACTOR AS WELL. WHILE TEMPERATURES WON`T
BE AS COLD THURSDAY NIGHT/FRIDAY MORNING, WINDS WILL BE GUSTING
20-25 MPH. THIS WILL CREATE WIND CHILLS AS LOW AS -20F ACROSS THE
POCONOS, -10 TO -15F ACROSS THE LEHIGH VALLEY AND NORTHWEST NEW
JERSEY, 0 TO -10 ACROSS MOST EVERYWHERE ELSE. WITH LESS WIND FRIDAY
NIGHT/SATURDAY MORNING, WIND CHILLS WILL RANGE FROM 15 ABOVE TO -15.
PRECIPITATION...WHILE A MIX OF SNOW, SLEET AND RAIN SHOULD DEVELOP
LATER ON THURSDAY. THIS TURNS TO ALL SNOW ON THURSDAY NIGHT AND
STAYS THAT WAY ON FRIDAY BEFORE ENDING. SATURDAY REMAINS DRY. ON
SUNDAY, THE NEXT BATCH OF PRECIPITATION SHOULD ARRIVE WITH THE
COLD FRONT. THIS LOOKS MORE LIKE A MIXED AND/OR RAIN EVENT.
TUESDAY LOOKS DRY AT THIS TIME.
IMPACTS...WHILE SOME SNOW COULD BEGIN TO ACCUMULATE ON THURSDAY N
OF I80, SIGNIFICANT IMPACTS COULD BE FELT THURSDAY NIGHT INTO
FRIDAY. IMPACTS INCLUDE THE COMBINATION OF A BITTERLY COLD
AIRMASS, GUSTY WINDS PRODUCING DANGEROUS WIND CHILLS, LOW
VISIBILITIES DUE TO FALLING AND BLOWING SNOW. THE SNOW WILL BE
FLUFFY WITH 20- TO POTENTIALLY 30-1 RATIOS WHERE TEMPERATURES ARE
IN THE SINGLE DIGITS. 15-1 RATIOS SHOULD BE COMMON WHERE TEMPS
HANG OUT IN THE TEENS.
FURTHER COMPLICATING THIS TIME FRAME WILL BE THE POTENTIAL OF
COASTAL (TIDAL) FLOODING AND FREEZING SPRAY ON AND RIGHT NEXT TO
AREA WATERS. MORE ON THIS BELOW.
MORE IMPACTS COULD BE REALIZED ON SUNDAY AND SUNDAY NIGHT WITH THE
COLD FRONT, BUT LOOKS MORE CONFINED TO THE NORTH AND WEST ZONES.
HEADLINES...WINTER STORM WATCH I80 NORTH 23Z THURSDAY THROUGH 15Z
FRIDAY.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
REMAINDER OF TODAY...VFR WITH SCT-BKN AOA 10000 FT. WINDS GRADUALLY
BECOME LIGHT SOUTHWEST TO SOUTH.
TONIGHT...GENERALLY VFR CONDITIONS EXPECTED WITH LOWERING CIGS
ESPECIALLY VCNTY KABE KTTN. EASTERLY WINDS 5 TO 10 KNOTS.
THURSDAY...VFR LOWERING TO MVFR/IFR, ESPECIALLY KABE-KSMQ. GUSTY
ENE WIND DEVELOPING BY LATE IN THE DAY.
OUTLOOK...
THURSDAY NIGHT...MVFR TO IFR IN PERIODS OF SNOW. NORTHWEST WINDS
INCREASING OVERNIGHT THURSDAY.
FRIDAY AND FRIDAY NIGHT....CONDITIONS IMPROVING TO VFR. STRONG
NORTHWEST WINDS EXPECTED FRIDAY, DIMINISHING OVERNIGHT.
SATURDAY...VFR.
SUNDAY...POSSIBLE MVFR WITH LIGHT RAIN AND SNOW ON SUNDAY. POSSIBLE
IFR AT NIGHT WITH HEAVIER PRECIPITATION.
&&
.MARINE...
THE CALM BEFORE THE STORM TODAY AND TONIGHT AS SEAS AND WINDS ARE
EXPECTED TO REMAIN BELOW SCA CONDITIONS. WEST WINDS THIS
MORNING IN THE 10 TO 15 KNOT RANGE WILL BECOME SOUTHWEST, THEN
SOUTH, THEN SOUTHEAST LATE IN THE DAY ALL IN THE 5 TO 10 KNOT RANGE.
SOUTHEAST WINDS MAY INCREASE SLIGHTLY INTO THE 10 TO 15 KNOT RANGE
THIS EVENING.
TONIGHT...SUB-ADVISORY CONDITIONS ARE EXPECTED.
THURSDAY...WHILE SCA CONDITIONS ARE EXPECTED TO DEVELOP WITH STRENGTHENING
LOW PRESSURE TRACKING CLOSER TO THE REGION WE WILL PROBABLY OPT FOR
A STRAIGHT GALE THU NIGHT- FRI PER STRONG 03Z/1 SREF SIGNAL (40
PCT 34 KT SUSTAINED). WE MAY BEGIN THE GALE IN THE NNJ WATERS AT
4 PM THURSDAY.
OUTLOOK...
THURSDAY NIGHT-FRIDAY...GALE FORCE WIND GUSTS ARE LIKELY ALONG
WITH INCREASING SEAS. LIGHT FREEZING SPRAY IS ALSO EXPECTED...
ESPECIALLY THE NORTHERN NEW JERSEY WATERS FRIDAY MORNING. A GALE
WATCH HAS BEEN ISSUED.
FRIDAY NIGHT...SCA CONDITIONS ARE EXPECTED.
SATURDAY AND SUNDAY...SUB-ADVISORY CONDITIONS ARE EXPECTED.
&&
.TIDES/COASTAL FLOODING...
A LOW PRESSURE SYSTEM IS EXPECTED TO STRENGTHEN AS IT TRACKS
NORTHEAST OFF THE EASTERN SEABOARD THURSDAY INTO FRIDAY. THIS IN
CONJUNCTION WITH THE NEW MOON HAVING JUST OCCURRED ON WEDNESDAY WILL
LEAD TO AN INCREASE IN TOTAL TIDE LEVELS. THE THURSDAY MORNING AND
FRIDAY MORNING HIGH TIDE CYCLES WILL NEED TO BE MONITORED. MINOR
TIDAL FLOODING MAY BE APPROACHED WITH THE THURSDAY MORNING HIGH
TIDE FROM SANDY HOOK TO CAPE MAY AND ALSO AT LEWES, DELAWARE. THE
FRIDAY MORNING HIGH TIDE CYCLE IS OF GREATER CONCERN AS CURRENT
GUIDANCE INDICATES THE POTENTIAL FOR MODERATE COASTAL FLOODING,
WITH THE NORTHERN COAST OF NJ HAVING THE HIGHEST DEPARTURES,
INCLUDING THE COASTS OF MONMOUTH AND OCEAN COUNTIES AND INTO
RARITAN BAY. IN ADDITION, DELAWARE BAY WOULD ALSO BE AT RISK FOR
MODERATE COASTAL FLOODING WITH THE FRIDAY MORNING HIGH TIDE.
TRENDS WILL CONTINUE TO BE MONITORED AS WE GET CLOSER TO THE
EVENT.
ELSEWHERE, TIDAL FLOODING IS NOT EXPECTED AT THIS TIME INTO THE
TIDAL DELAWARE RIVER OR ALONG THE EASTERN SHORE OF CHESAPEAKE BAY,
BUT MODEL GUIDANCE WILL CONTINUE TO BE MONITORED.
&&
.CLIMATE...
FOR A PERSPECTIVE AT THIS FORECAST JUNCTURE...
THE COLD TEMPERATURES FORECAST SATURDAY MORNING WILL BE THE
COLDEST AT LEAST DATING BACK AS FOLLOWS:
OUR LATEST FORECAST FOR SATURDAY MORNING JANUARY 4, 2014:
KILG AROUND 7F. LAST TIME WAS 1/16-17/2009 AT 7 AND 5 RESPECTIVELY.
KPHL AROUND 7F. LAST TIME WAS JAN 17, 2009.
KABE AROUND 0F. LAST TIME THIS COLD WAS JAN 24, 2011.
FOR THOSE LOOKING AT RECORDS WITH A PROBABLE FRESH SNOW COVER TO
ASSIST MAGNIFYING THE INCOMING LATE WEEK COLD AIRMASS...
1/3 1/4
KACY...-2 1879 0 1918 POR 1874
KPHL...-3 1879 2 1918 POR 1872
KILG...+4 1918 -1 1918 POR 1894
KABE...+6 1945 -4 1981 POR 1922
KTTN...-4 1879 -1 1918 POR 1865
KGED...+8 1962 4 1979 POR 1948
KRDG...+1 1918 -5 1981 POR 1869
KMPO...-7 1904 -23 1981 POR 1901
POR = PERIOD OF RECORD.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WATCH FROM THURSDAY EVENING THROUGH FRIDAY
MORNING FOR PAZ054-055-062.
NJ...WINTER STORM WATCH FROM THURSDAY EVENING THROUGH FRIDAY
MORNING FOR NJZ001-007-008.
DE...NONE.
MD...NONE.
MARINE...GALE WATCH FROM LATE THURSDAY NIGHT THROUGH FRIDAY AFTERNOON
FOR ANZ430-431-452>455.
GALE WATCH FROM THURSDAY EVENING THROUGH FRIDAY AFTERNOON FOR
ANZ450-451.
&&
$$
SYNOPSIS...DRAG/KRUZDLO 1034A
NEAR TERM...DRAG 1034A
SHORT TERM...DRAG 1034A
LONG TERM...KRUZDLO
AVIATION...DRAG/KRUZDLO 1034A
MARINE...DRAG/KRUZDLO 1034A
TIDES/COASTAL FLOODING...
CLIMATE...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
850 AM EST WED JAN 1 2014
.SYNOPSIS...
HAPPY NEW YEAR! HIGH PRESSURE OVER THE DELMARVA SHIFTS OFFSHORE
THIS AFTERNOON. AN ARCTIC COLD FRONT STRETCHED FROM NORTHERN NEW
ENGLAND TO TORONTO AND INDIANAPOLIS WILL SETTLE SOUTHWARD TONIGHT.
TWO LOW PRESSURE SYSTEMS WILL DEVELOP BY THURSDAY, ONE ACROSS THE
APPALACHIANS AND A SECONDARY LOW OFF OF THE CAROLINA COAST. THESE
WILL MERGE INTO ONE LOW OFFSHORE ON FRIDAY AND INTENSIFY AS IT
MOVES AWAY FROM OUR REGION. HIGH PRESSURE WILL THEN BUILD IN FOR
MOST OF THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
VARIABLE MOSTLY HIGH CLOUDS TODAY. BOTH THE 11Z/1 HRRR AND RAP
MODELS ARE FCSTG MEASURABLE SNOW TO MOVE INTO NORTHERN MONROE
AND NORTHERN SUSSEX COUNTIES THIS AFTERNOON IN THE WARM AIR
ADVECTION AHEAD OF THE SWD MOVING ARCTIC BOUNDARY. HALF AN INCH
OR SO IS POSSIBLE LATE THIS AFTERNOON THERE AND PRESUMING THE 12Z
NAM CONFIRMS...WE WILL ENSURE THIS IS ACCOUNTED FOR THE 930 AM
UPDATE... SO THIS SMALL CHANGE IS PENDING THE 930AM UPDATE AND
RECEIPT OF THE FIRST 24 HRS OF THE 12Z/1 NAM. THAT WOULD MEAN POPS
INCREASED 40 PCT IN THOSE TWO COUNTIES AND SNOWFALL INCREASED BY
.4. THE 00Z/1 SPC WRF HAS NOT FCST THIS HRRR/RAP SOLN.
OTRW THE 330 AM FCST IS PROBABLY UNCHANGED AT 930 AM WITH THE
STANDARD MINOR ADJUSTMENTS FOR REALITY TEMPS/SKYCOVER.
TODAY`S TEMPS NORMAL TO SLIGHTLY BELOW NORMAL FOR THIS TIME OF
YEAR.
TONIGHT...THE SPC WRF AND SOME OTHER MODELS ARE BREAKING OUT PCPN
FROM COASTAL NNJ THROUGH NW NJ AFTER ROUGHLY 05Z. WE`LL MONITOR
THE MODELS FOR SNOW AND OR ICE AND CONSIDER FOR THE 330 PM
ISSUANCE A PRE STORM ADVY IF ICE?
&&
.SHORT TERM /THURSDAY/...
00Z CYCLES WERE HIGHLY DIVERGENT ON THE UPCOMING EVENT WITH THE
ECMWF AND GFS QPF ABOUT 30 PCT OF THE NAM WHICH WAS MODELING MUCH
MORE EMPHASIS ON THE TRAILING SFC LOW NEAR THE COAST INSTEAD OF
THE PROBABLE PRIMARY FURTHER EAST OFF THE MID ATLC COAST....NEAR
38/70 BY DAYS END. THERE WILL BE TREMENDOUS CYCLONIC CURVATURE
LATE THU AFTN AND THE ARCTIC BOUNDARY SINKING SWD WILL PROVIDE
FURTHER LIFT IN THE I80 REGION NWD AS THE ARCTIC AIR BEGINS ITS
SWD INTRUSION.
ALL THE 00Z/1 CYCLE MODELS HAVE A DRY WEDGE BETWEEN ROUGHLY
800-650 MB THURSDAY MORNING/MIDDAY.
SO THE DAYTIME EVOLUTION IS STILL MUCH IN DOUBT THO THE SREF
IMPLIES 1-3" OF NEW SNOW ACCUMULATION BETWEEN DAYBREAK THU AND
SUNSET THU I80 REGION OR NORTH OF THAT ACROSS NORTHERN MONROE AND
NORTHERN SUSSEX COUNTIES IN NJ. ELSEWHERE...ESPECIALLY S OF
I78...ABOVE FREEZING TEMPS AND LITTLE GOING ON DURING THE DAY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
OVERVIEW...THE PERIOD BEGINS WITH THE POLAR/ARCTIC JET INDUCING LOW
PRESSURE OVER THE CENTRAL APPALACHIANS WHILE A TON OF MOISTURE POOLS
NEAR A FRONT, A SURFACE LOW, AND THE SOUTHERN STREAM JET ACROSS THE
SOUTHEASTERN STATES. ON THURSDAY NIGHT, THE TWO LOWS BEGIN TO PHASE
OFFSHORE. COME FRIDAY, THE MERGED LOW DEEPENS WELL OFFSHORE. SURFACE
HIGH PRESSURE WITH A MID-LEVEL ZONAL FLOW SETS UP ON FRIDAY NIGHT.
THE HIGH DRIFTS OFFSHORE SATURDAY AND SATURDAY NIGHT OFFERING A
BRIEF RETURN FLOW. A COLD FRONT WILL APPROACH THE REGION, FROM THE
WEST, ON SUNDAY BEFORE MOVING THROUGH ON SUNDAY NIGHT, ALONG WITH A
WAVE OF LOW PRESSURE. THE REGION COULD EXPERIENCE SOME BREEZY
CONDITIONS ON MONDAY WITH LOW PRESSURE TO OUR EAST AND A HIGH TO OUR
WEST. HIGH PRESSURE WILL BUILD FURTHER EAST ON MONDAY NIGHT AND
TUESDAY.
TEMPERATURES...BELOW/WELL BELOW NORMAL THURSDAY NIGHT THROUGH
SATURDAY. ABOUT NORMAL SUNDAY AND MONDAY. BELOW/WELL BELOW NORMAL
ONCE AGAIN ON TUESDAY.
BITTERLY COLD TEMPERATURES ARE EXPECTED THURSDAY NIGHT/FRIDAY
MORNING AND AGAIN FRIDAY NIGHT/SATURDAY MORNING WITH THE LATTER DAY
THE COLDER OF THE TWO. THE LEHIGH VALLEY AND NORTHWESTERN NEW JERSEY
COULD SEE SUB-ZERO TEMPERATURE FRIDAY NIGHT AND SATURDAY MORNING
WITH SINGLE DIGITS JUST ABOUT EVERYWHERE ELSE.
WIND WILL BE A SIGNIFICANT FACTOR AS WELL. WHILE TEMPERATURES WON`T
BE AS COLD THURSDAY NIGHT/FRIDAY MORNING, WINDS WILL BE GUSTING
20-25 MPH. THIS WILL CREATE WIND CHILLS AS LOW AS -20F ACROSS THE
POCONOS, -10 TO -15F ACROSS THE LEHIGH VALLEY AND NORTHWEST NEW
JERSEY, 0 TO -10 ACROSS MOST EVERYWHERE ELSE. WITH LESS WIND FRIDAY
NIGHT/SATURDAY MORNING, WIND CHILLS WILL RANGE FROM 15 ABOVE TO -15.
PRECIPITATION...WHILE A MIX OF SNOW, SLEET AND RAIN SHOULD DEVELOP
LATER ON THURSDAY. THIS TURNS TO ALL SNOW ON THURSDAY NIGHT AND
STAYS THAT WAY ON FRIDAY BEFORE ENDING. SATURDAY REMAINS DRY. ON
SUNDAY, THE NEXT BATCH OF PRECIPITATION SHOULD ARRIVE WITH THE
COLD FRONT. THIS LOOKS MORE LIKE A MIXED AND/OR RAIN EVENT.
TUESDAY LOOKS DRY AT THIS TIME.
IMPACTS...WHILE SOME SNOW COULD BEGIN TO ACCUMULATE ON THURSDAY N
OF I80, SIGNIFICANT IMPACTS COULD BE FELT THURSDAY NIGHT INTO
FRIDAY. IMPACTS INCLUDE THE COMBINATION OF A BITTERLY COLD
AIRMASS, GUSTY WINDS PRODUCING DANGEROUS WIND CHILLS, LOW
VISIBILITIES DUE TO FALLING AND BLOWING SNOW. THE SNOW WILL BE
FLUFFY WITH 20- TO POTENTIALLY 30-1 RATIOS WHERE TEMPERATURES ARE
IN THE SINGLE DIGITS. 15-1 RATIOS SHOULD BE COMMON WHERE TEMPS
HANG OUT IN THE TEENS.
FURTHER COMPLICATING THIS TIME FRAME WILL BE THE POTENTIAL OF
COASTAL (TIDAL) FLOODING AND FREEZING SPRAY ON AND RIGHT NEXT TO
AREA WATERS. MORE ON THIS BELOW.
MORE IMPACTS COULD BE REALIZED ON SUNDAY AND SUNDAY NIGHT WITH THE
COLD FRONT, BUT LOOKS MORE CONFINED TO THE NORTH AND WEST ZONES.
HEADLINES...WINTER STORM WATCH I80 NORTH 23Z THURSDAY THROUGH 15Z
FRIDAY.
&&
.AVIATION /13Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TODAY...VFR, WITH CLOUD CEILINGS MAINLY OF THE MID TO HIGH LEVEL
VARIETY. WINDS GRADUALLY BECOME LIGHT SOUTHWEST TO SOUTH.
TONIGHT...GENERALLY VFR CONDITIONS EXPECTED WITH LOWERING CLOUDS
ESPECIALLY IN THE NORTH. EASTERLY WINDS 5 TO 10 KNOTS BECOMING
VARIABLE TOWARD DAYBREAK.
THURSDAY...VFR LOWERING TO MVFR/IFR, ESPECIALLY KABE-KSMQ.
OUTLOOK...
THURSDAY NIGHT...MVFR TO IFR IN PERIODS OF SNOW. NORTHWEST WINDS
INCREASING OVERNIGHT THURSDAY.
FRIDAY AND FRIDAY NIGHT....CONDITIONS IMPROVING TO VFR. STRONG
NORTHWEST WINDS EXPECTED FRIDAY, DIMINISHING OVERNIGHT.
SATURDAY...VFR.
SUNDAY...POSSIBLE MVFR WITH LIGHT RAIN AND SNOW ON SUNDAY. POSSIBLE
IFR AT NIGHT WITH HEAVIER PRECIPITATION.
&&
.MARINE...
THE CALM BEFORE THE STORM TODAY AND TONIGHT AS SEAS AND WINDS ARE
EXPECTED TO REMAIN BELOW SCA CONDITIONS. WEST WINDS THIS
MORNING IN THE 10 TO 15 KNOT RANGE WILL BECOME SOUTHWEST, THEN
SOUTH, THEN SOUTHEAST LATE IN THE DAY ALL IN THE 5 TO 10 KNOT RANGE.
SOUTHEAST WINDS MAY INCREASE SLIGHTLY INTO THE 10 TO 15 KNOT RANGE
THIS EVENING.
TONIGHT...SUB-ADVISORY CONDITIONS ARE EXPECTED.
THURSDAY...WHILE SCA CONDITIONS ARE EXPECTED TO DEVELOP LATER IN
THE DAY, AS WINDS AND SEAS INCREASE WITH STRENGTHENING LOW PRESSURE
TRACKING CLOSER TO THE REGION WE WILL PROBABLY OPT FOR A STRAIGHT
GALE THU NIGHT-FRI PER STRONG SREF SIGNAL (40 PCT 34 KT SUSTAINED).
OUTLOOK...
THURSDAY NIGHT-FRIDAY...GALE FORCE WIND GUSTS ARE LIKELY ALONG
WITH INCREASING SEAS. LIGHT FREEZING SPRAY IS ALSO EXPECTED...
ESPECIALLY THE NORTHERN NEW JERSEY WATERS FRIDAY MORNING. A GALE
WATCH HAS BEEN ISSUED.
FRIDAY NIGHT...SCA CONDITIONS ARE EXPECTED.
SATURDAY AND SUNDAY...SUB-ADVISORY CONDITIONS ARE EXPECTED.
&&
.TIDES/COASTAL FLOODING...
A LOW PRESSURE SYSTEM IS EXPECTED TO STRENGTHEN AS IT TRACKS
NORTHEAST OFF THE EASTERN SEABOARD THURSDAY INTO FRIDAY. THIS IN
CONJUNCTION WITH THE NEW MOON HAVING JUST OCCURRED ON WEDNESDAY WILL
LEAD TO AN INCREASE IN TOTAL TIDE LEVELS. THE THURSDAY MORNING AND
FRIDAY MORNING HIGH TIDE CYCLES WILL NEED TO BE MONITORED. MINOR
TIDAL FLOODING MAY BE APPROACHED WITH THE THURSDAY MORNING HIGH
TIDE FROM SANDY HOOK TO CAPE MAY AND ALSO AT LEWES, DELAWARE. THE
FRIDAY MORNING HIGH TIDE CYCLE IS OF GREATER CONCERN AS CURRENT
GUIDANCE INDICATES THE POTENTIAL FOR MODERATE COASTAL FLOODING,
WITH THE NORTHERN COAST OF NJ HAVING THE HIGHEST DEPARTURES,
INCLUDING THE COASTS OF MONMOUTH AND OCEAN COUNTIES AND INTO
RARITAN BAY. IN ADDITION, DELAWARE BAY WOULD ALSO BE AT RISK FOR
MODERATE COASTAL FLOODING WITH THE FRIDAY MORNING HIGH TIDE.
TRENDS WILL CONTINUE TO BE MONITORED AS WE GET CLOSER TO THE
EVENT.
ELSEWHERE, TIDAL FLOODING IS NOT EXPECTED AT THIS TIME INTO THE
TIDAL DELAWARE RIVER OR ALONG THE EASTERN SHORE OF CHESAPEAKE BAY,
BUT MODEL GUIDANCE WILL CONTINUE TO BE MONITORED.
&&
.CLIMATE...
FOR A PERSPECTIVE AT THIS FORECAST JUNCTURE...
THE COLD TEMPERATURES FORECAST SATURDAY MORNING WILL BE THE
COLDEST AT LEAST DATING BACK AS FOLLOWS:
OUR LATEST FORECAST FOR SATURDAY MORNING JANUARY 4, 2014:
KILG AROUND 7F. LAST TIME WAS 1/16-17/2009 AT 7 AND 5 RESPECTIVELY.
KPHL AROUND 7F. LAST TIME WAS JAN 17, 2009.
KABE AROUND 0F. LAST TIME THIS COLD WAS JAN 24, 2011.
FOR THOSE LOOKING AT RECORDS WITH A PROBABLE FRESH SNOW COVER TO
ASSIST MAGNIFYING THE INCOMING LATE WEEK COLD AIRMASS...
1/3 1/4
KACY...-2 1879 0 1918 POR 1874
KPHL...-3 1879 2 1918 POR 1872
KILG...+4 1918 -1 1918 POR 1894
KABE...+6 1945 -4 1981 POR 1922
KTTN...-4 1879 -1 1918 POR 1865
KGED...+8 1962 4 1979 POR 1948
KRDG...+1 1918 -5 1981 POR 1869
KMPO...-7 1904 -23 1981 POR 1901
POR = PERIOD OF RECORD.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WATCH FROM THURSDAY EVENING THROUGH FRIDAY
MORNING FOR PAZ054-055-062.
NJ...WINTER STORM WATCH FROM THURSDAY EVENING THROUGH FRIDAY
MORNING FOR NJZ001-007-008.
DE...NONE.
MD...NONE.
MARINE...GALE WATCH FROM LATE THURSDAY NIGHT THROUGH FRIDAY AFTERNOON
FOR ANZ430-431-452>455.
GALE WATCH FROM THURSDAY EVENING THROUGH FRIDAY AFTERNOON FOR
ANZ450-451.
&&
$$
SYNOPSIS...KRUZDLO/DRAG 850A
NEAR TERM...DRAG/MIKETTA 850A
SHORT TERM...DRAG/MIKETTA 850A
LONG TERM...KRUZDLO
AVIATION...DRAG/KRUZDLO 850A
MARINE...DRAG/KRUZDLO 850A
TIDES/COASTAL FLOODING...
CLIMATE...
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
1004 AM EST WED JAN 1 2014
.UPDATE...CENTRAL CONUS TROF WILL CONTINUE TO NUDGE EASTWARD TODAY
WITH LARGE SCALE ASCENT INCREASING WITH SHORTWAVES SWINGING
ACROSS THE GULF OF MEXICO INTO NORTHERN FLORIDA AND SOUTHERN
GEORGIA THROUGH THE DAY. OVERCAST MIDDLE LEVEL CLOUD DECK STILL
HOVERING AROUND 10KFT WITH SOME LOWER CUMULUS STARTING TO DEVELOP
THIS MORNING AOA 4-5 KFT. THIS MORNINGS JAX 12Z SOUNDING SHOWED
DRY LAYER IN THE 700 TO 850 MB LATER LENDING TO A LOW PWAT OF 1.14
INCHES. LOW LEVEL MOISTURE ADVECTION SHOULD CONTINUE THIS LATE
MORNING...TURNING THE MORNING PARADIGM OF LIGHT SHOWERS AND VIRGA
INTO A INTERMIXING OF LIGHT RAIN WITH OCCASIONAL MODERATE SHOWERS
DURING THE AFTERNOON. THE UPSTREAM SOUNDING AT TAMPA WAS 1.57
INCHES. THE HRRR DOES DEPICT MORE WIDESPREAD SHOWERS THIS
AFTERNOON WITH SOME EMBEDDED BUT STILL SPOTTY MODERATE SHOWER
ACTIVITY. MORE WIDESPREAD RAIN IS ANTICIPATED TONIGHT AS LOW
LEVELS BECOME MORE SATURATED.
&&
.AVIATION...CEILINGS WILL GRADUALLY LOWER THIS AFTERNOON AND
BECOME MVFR THIS AFTERNOON AND THEN IFR TONIGHT. LIGHT RAIN
SHOWERS WILL GRADUALLY INCREASE IN COVERAGE AND INTENSITY THIS
AFTERNOON WITH IFR VISIBILITIES POSSIBLE IN A STEADY PERIOD OF A
MORE MODERATE RAINFALL TONIGHT.
&&
.MARINE...
ONSHORE WINDS OF 10 TO 15 KNOTS WILL CONTINUE WITH SEAS IN THE 2
TO 4 FOOT RANGE. FORECAST DOES BECOMES A LITTLE MORE COMPLICATED
TONIGHT AS A TROUGH BEGINS TO DEVELOP OFFSHORE WITH WINDS TURNING
TO THE SOUTH ACROSS THE FLORIDA WATERS. DEPENDING ON STRENGTH OF
TROUGH...WIND SPEEDS TONIGHT MAY END UP A LITTLE HIGHER THAN
CURRENTLY FORECAST BUT STILL EXPECTED TO REMAIN BELOW ADVISORY
LEVELS.
RIP CURRENTS: LOW RISK.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 56 48 63 33 / 60 100 100 30
SSI 57 54 61 35 / 80 100 100 50
JAX 59 56 65 33 / 90 100 100 50
SGJ 62 60 70 37 / 90 90 100 60
GNV 61 57 68 36 / 80 80 90 60
OCF 63 58 72 41 / 70 70 80 60
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
TRABERT/CORDERO/MCALLISTER
AREA FORECAST DISCUSSION
NWS MIAMI FL
942 AM EST WED JAN 1 2014
.UPDATE...
NO MAJOR CHANGES TO THE FORECAST THIS MORNING. MAINLY ADJUSTED
POPS TO REFLECT CURRENT CONDITIONS AND MODEL TRENDS FOR THIS
AFTERNOON. THE HRRR SHOWS MOST SHOWER ACTIVITY WILL BE NORTH OF I75
THIS AFTERNOON. HOWEVER, THERE IS STILL INDICATION THAT ALL OF
SOUTH FLORIDA COULD SEE AT LEAST ISOLATED SHOWER ACTIVITY AS
ISENTROPIC LIFT INCREASES THROUGH THE DAY. BUT, IT DOES APPEAR THAT
IT WILL BE MORE CONDUCIVE TO SHOWERS FURTHER TO THE NORTH. THERE
ALSO SEEMS TO BE A WEAK, EMBEDDED SHORT WAVE THAT WILL PASS OVER
CENTRAL FLORIDA THIS AFTERNOON. MODELS ARE INDICATING THAT
SLIGHTLY DRIER AIR WILL TRY TO MOVE IN FROM THE SOUTH. THIS IS
REFLECTED IN THE WATER VAPOR IMAGERY. THE GFS IS SHOWING PWATS
WILL DROP FROM AROUND 1.6 INCHES TO AROUND 1.25 INCHES SOUTH OF
THE I75 LINE, COINCIDING WITH MODEL OUTPUT OF PRECIPITATION. SO,
HAVE KEPT HIGH END CHANCE POPS FOR THE LAKE REGION AND PALM BEACH
COUNTIES TAPERING TO SLIGHTS CHANCE TO THE SOUTH.
&&
.PREV DISCUSSION... /ISSUED 631 AM EST WED JAN 1 2014/
AVIATION...
A FRONTAL BOUNDARY ACROSS THE FLORIDA STRAITS WILL LIFT NORTHWARD
TODAY AS A WARM FRONT ACROSS SOUTH FLORIDA. LOW VFR/HIGH MVFR
CONDITIONS ARE LIKELY TO PREVAIL THROUGH THE MORNING AND INTO THE
EARLY AFTERNOON HOURS...ESPECIALLY FOR AREAS THAT REMAIN NEAR AND
NORTH OF THE FRONT. LIGHT SHOWERS/DRIZZLE WAS BEGINNING TO INCREASE
IN COVERAGE ACROSS THE REGION...AND SCATTERED MAINLY LIGHT SHOWERS
ARE FORECAST THROUGH THE DAY. SKY CONDITIONS ARE FORECAST TO IMPROVE
FROM SOUTH TO NORTH THIS AFTERNOON INTO THE EVENING. HOWEVER...CIGS
AT 4-5 KFT ARE FORECAST TO PREVAIL THROUGH THE TAF PERIOD. EAST
WINDS AROUND 12 KNOTS WILL SHIFT TO THE SOUTHEAST THIS AFTERNOON.
PREV DISCUSSION... /ISSUED 324 AM EST WED JAN 1 2014/
SYNOPSIS...
WARM AND HUMID CONDITIONS WILL PERSIST THROUGH THURSDAY
NIGHT...BEFORE A COLD FRONT MOVES IN...BRINGING SLIGHTLY COOLER
AND DRIER WEATHER FOR THE END OF THE WEEK.
SHORT TERM /TODAY THROUGH FRIDAY/...
EASTERLY FLOW IS CONTINUING EARLY THIS MORNING...WITH MODEST
ISENTROPIC LIFT RESPONSIBLE FOR PERIODS OF DRIZZLE AND A FEW LIGHT
SHOWERS...MAINLY OVER METRO MIAMI AND FT LAUDERDALE. A WEAK
SURFACE TROUGH/REMNANT STATIONARY FRONT OVER THE FLORIDA STRAITS
WILL LIFT NORTHWARD TODAY. AS IT DOES...THE INCREASED CONVERGENCE
AND CONTINUED ISENTROPIC LIFT SHOULD LEAD TO SOME OVERRUNNING
SHOWERS...ESPECIALLY BY THIS AFTERNOON...NEAR AND NORTH OF THE
LOW-LEVEL FEATURE. POPS HAVE BEEN RAISED ACCORDINGLY...WITH BEST
CHANCES ACROSS NORTHERN HALF OF CWA. ASSUMING BOUNDARY LIFTS NORTH
AS FORECAST...SOUTHERN AREAS SHOULD RECEIVE MORE SUNSHINE THAN
PREVIOUS FEW DAYS...THUS MAXIMA ARE FORECAST TO REACH LOW 80S.
AFTER THE PSEUDO-WARM FRONT REACHES CENTRAL FLORIDA...SHOWER
COVERAGE SHOULD DIMINISH OVER SOUTH FLORIDA...ALTHOUGH WARM AND
HUMID CONDITIONS WILL PREVAIL TONIGHT THROUGH THURSDAY EVENING.
LOW-LEVEL WINDS WILL TRANSITION TO SOUTHERLY AS LOW PRESSURE
ORGANIZES IN THE NORTHERN GULF OF MEXICO. PARENT UPPER-LEVEL
TROUGH AXIS WILL SWING THROUGH THE EASTERN CONUS
THURSDAY...QUICKLY LIFTING THE SURFACE LOW NORTHEASTWARD INTO THE
MID-ATLANTIC. ATTENDANT COLD FRONT IS PROGGED TO MOVE THROUGH THE
FLORIDA PENINSULA THURSDAY NIGHT...CLEARING SOUTH FLORIDA BY DAWN
FRIDAY. SHOWER CHANCES ARE LOW WITH THIS FRONT...BUT LATEST
GUIDANCE IS INDICATING SIGNIFICANT COOL AIR BEHIND THE FRONT.
THUS...FORECAST MAXIMA FRIDAY HAVE BEEN LOWERED SEVERAL
DEGREES...AND MAY EXHIBIT LITTLE DIURNAL TREND. EXPECT
TEMPERATURES TO STRUGGLE TO REACH 70F MOST AREAS...WITH NORTHERN
PORTIONS OF THE AREA POSSIBLY REMAINING IN THE LOWER 60S DURING
THE AFTERNOON...WITH BREEZY NORTH WINDS.
LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE HIGH PRESSURE RIDGE RESPONSIBLE FOR THE COOLER WEATHER FRIDAY
APPEARS QUITE PROGRESSIVE...AND WILL HEAD OFF THE EASTERN
SEABOARD FRIDAY NIGHT AND SATURDAY. OVER SOUTH FLORIDA...WINDS
SHOULD TURN ONSHORE OVERNIGHT FRIDAY...CURBING COOLING AND KEEPING
TEMPERATURES FROM FALLING TO BELOW NORMAL VALUES.
STILL...MINIMA WILL BE COOLER THAN PREVIOUS SEVERAL DAYS...LIKELY
RANGING FROM UPPER 40S OVER GLADES AND HENDRY CONTINUES...TO
L/M60S ACROSS METRO MIAMI AND FT LAUDERDALE.
MOISTURE RETURNS OVER THE WEEKEND AS SOUTHERLY FLOW RE-
ESTABLISHES. THE REMNANTS OF THE EARLIER COLD FRONT WILL LIFT
NORTH BACK OVER THE REGION...BRINGING WELL ABOVE NORMAL
TEMPERATURES AND INCREASED SHOWER CHANCES...ESPECIALLY ON SUNDAY.
POTENT MID/UPPER-LEVEL TROUGH IS FORECAST TO DIVE INTO THE CENTRAL
CONUS OVER THE WEEKEND THEN PUSH TOWARD EASTERN SEABOARD ON
MONDAY. CONFIDENCE IS INCREASING THAT A COLD FRONT ASSOCIATED WITH
THIS SYSTEM WILL MOVE THROUGH SOUTH FLORIDA LATE MONDAY...BRINGING
COOLER TEMPERATURES. THERES SIGNIFICANT UNCERTAINTY AS TO THE
STRENGTH AND POSITION OF THE HIGH PRESSURE /ARCTIC IN ORIGIN/ BEHIND
THIS FRONT...THUS CONFIDENCE IS LOW IN HOW MUCH COOLER
TEMPERATURES WILL IN SOUTH FLORIDA ON TUESDAY. FOR NOW...FORECAST
TEMPERATURES REFLECT A RETURN TO NEAR/SLIGHTLY BELOW NORMAL
VALUES FOR THE END OF THE EXTENDED.
MARINE...
WEAK SURFACE BOUNDARY WILL LIFT NORTHWARD ACROSS THE WATERS
TODAY...GRADUALLY TRANSITIONING WINDS TO THE SOUTH. A COLD FRONT
WILL MOVE ACROSS EARLY FRIDAY MORNING...LIKELY BRINGING HAZARDOUS
WINDS AND SEAS. WINDS AND SEAS GRADUALLY SUBSIDE OVER THE WEEKEND.
ANOTHER FRONT MAY IMPACT THE WATERS EARLY NEXT WEEK. A SLIGHT
CHANCE FOR SHOWERS EXISTS THROUGH THE PERIOD...BUT BETTER CHANCES
ARE FORECAST TODAY AND SUNDAY.
EAST WINDS TODAY OF 15-20 KTS WARRANT SMALL CRAFT EXERCISE CAUTION
STATEMENT FOR ATLANTIC WATERS. LIGHTER SOUTHERLY WINDS ARE
FORECAST TONIGHT...BUT AS LOW PRESSURE STRENGTHENS OVER THE
NORTHERN GULF OF MEXICO...SOUTH WINDS WILL INCREASE AGAIN ON
THURSDAY AND THURSDAY NIGHT...AHEAD OF A COLD FRONT. BEHIND THIS
COLD FRONT...WINDS AND SEAS ARE EXPECTED REACH SMALL CRAFT
ADVISORY CONDITIONS...AND THIS MAY CONTINUE INTO SATURDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 81 72 84 63 / 50 20 20 20
FORT LAUDERDALE 80 74 83 65 / 50 20 20 10
MIAMI 83 72 83 66 / 30 20 20 10
NAPLES 83 69 82 61 / 20 20 30 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...13/SI
AVIATION/RADAR...60/BD
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
604 AM CST Wed Jan 1 2014
...Updated for aviation discussion...
.SYNOPSIS...
ISSUED AT 339 AM CST WED JAN 1 2014
Water vapor loop during the overnight hours showed a digging
shortwave trough across eastern Wyoming...reaching northern Colorado
as of 09Z. This shortwave trough encompassed a much larger scale
gyre that was centered over southeastern Hudson Bay. In the lower
troposphere, temperatures were fairly mild on the High Plains with
850mb temperatures from +8 to +10C. Meanwhile, the very sharp
baroclinic zone at 850mb was found from northeastern Montana through
northeastern Nebraska per 00Z RAOB and RAP analysis. Surface
temperatures across Nebraska on the 09Z analysis ranged from 35F at
Scottsbluff to +8F at O`Neill on the other side of the front. Below
zero temperatures (degF) were not too far away into southeastern
South Dakota.
&&
.UPDATE...
ISSUED AT 504 AM CST WED JAN 1 2014
There seems to be enough of a signal in the most recent mesoscale
model solutions to bump up snowfall amounts in the northeast
counties (northeast of a Scott City to Jetmore to Pratt line). A
look at the 03Z run of the SREF Plumes for Hays indicates a mean
of all perturbations just under 2 inches. However, much of that is
influenced by the seemingly wet WRF-ARW core. The WRF-ARW
perturbations are clustered between 3 and 4 inches at Hays. While
we do not necessarily believe total snowfall will be quite that
high given the fast speed of the system, some brief moderate-high
snowfall rates as the 700mb zone of frontogenesis passes would
argue for at least an inch or two of final snowfall. As a result,
we have bumped up the snowfall just a bit to around an inch and a
half along I-70... and the half inch line down to roughly Scott
City-Jetmore-Pratt line. With the increased snowfall forecast, we
will have to think more about the blowing and drifting potential
as 18 to 22 knot sustained winds will add to reduced visibility
for a few hours this afternoon. We will hold off on issuing a
winter weather advisory with sub-two inch forecast amounts, but it
is something that the incoming day shift will need to monitor
closely.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 339 AM CST WED JAN 1 2014
As mentioned in the synopsis section, a sharp baroclinic zone was
found across Nebraska. As the mid-level shortwave trough moves
southeast into western Kansas today, some of this arctic air
residing in central Nebraska will advect southward on
northeast...and eventually due north winds. The problem in the
forecast for today is just how far southwest this arctic airmass
will reach. North-northwest winds at the surface near the Colorado
border will not be advecting in much of that arctic air at all (It
was still 31F in Douglas, WY and 35F in Scottsbluff, NE as of
09Z!). We foresee a fairly sharp temperature gradient across
western Kansas today. There is a rather high degree of uncertainty
in the temperature forecast west of Highway 283. The official
forecast will call for steady or falling temperatures through the
day northeast of roughly Dighton to Dodge City to Pratt. Northeast
of this line, there is a fairly high degree of confidence in the
temperature forecast...and that it will be very cold with
temperatures falling through the 20s...and into the mid to upper
teens potentially at Hays. Then there is the
Elkhart-Johnson-Syracuse corridor. This area, if they see any of
this arctic air at all, will be later in the day. This will allow
the Colorado border areas to warm well into the upper 30s to lower
40s. By early to mid afternoon, we could very well see a 30-degree
temperature gradient from southwest to northeast across the DDC
forecast area (from Elkhart to Hays).
Now on to the snow. Nothing much has really changed from previous
forecast thinking. The shortwave trough will be zipping southeast
quickly today, and there will only be a 2 to 4 hour period of light
to briefly moderate snow across the far northeastern zones (most
particularly, Hays-Victoria)...along the zone of strongest 700mb
frontogenesis. The best of this frontogenetic response at 700mb will
be just northeast of the DDC forecast area (across north-central
Kansas) as is indicated by the latest NAM12 and WRF runs. There
could be a brief period of some showery type snow along the Scott
City to Dodge City to Pratt corridor from midday to late afternoon
as a pocket of very slight potential instability develops in the mid
levels right near the 400-500mb potential vorticity anomaly. This
could put down a quickly quarter to half inch of snow in some
scattered spots along the Scott City-Dodge City-Pratt axis.
All of the snow and/or snow showers will be well east of the
southwest Kansas region by early this evening. Downslope
trajectories will resume overnight with a light westerly surface
wind developing especially along/west of Highway 83. Temperatures
should stabilize in the upper teens to lower 20s if not very slowly
rise toward 12Z. Across central Kansas, temperatures will likely
bottom out around +10F.
.LONG TERM...(Thursday through Tuesday)
ISSUED AT 348 AM CST WED JAN 1 2014
A warming trend will commence Thursday and Friday as the mid to
upper level flow becomes more zonal across the Rockies, and surface
pressures fall in the lee of the Rockies. Highs should make it
into the 40s in most places Thursday as the arctic air gets shunted
into eastern Kansas given the increasing low to mid level westerly
momentum. A progressive, positively tilted shortwave trough will
approach from the northwest by Saturday, and as one would expect with
a positively tilted system, a cold surge will pass through western
Kansas ahead of the feature. In spite of the cold advection, some
light snow is possible as the trough approaches, with only minor
accumulations of an inch or less expected. Then by Sunday, a lobe of
the polar vortex will rotate southeastward into the northern plains
and upper midwest. This will provide a glancing blow of arctic air
into Kansas for Sunday night into Monday, with moderating
temperatures by Tuesday and Wednesday into the 30s for highs as the
low level flow quickly becomes more westerly. The next upper
trough will approach Kansas by Wednesday and Thursday, but a lack
of deep moisture may preclude precipitation. However, if this
system is slower and more amplified, then some rain or snow would
be possible.
&&
.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
ISSUED AT 601 AM CST WED JAN 1 2014
A cold front will pass across the TAF sites this morning. MVFR
CIGS will develop well behind the front by late morning and early
afternoon. Light snow is expected to develop at KHYS by 18z and
persist for a few hours as an upper level disturbance passes, with
visbys falling to IFR or MVFR.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 27 16 38 19 / 30 10 0 0
GCK 31 18 41 18 / 30 10 0 0
EHA 46 21 47 24 / 10 10 0 0
LBL 39 21 45 24 / 10 10 0 0
HYS 20 11 33 15 / 80 10 0 0
P28 30 17 36 17 / 20 10 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Umscheid
SYNOPSIS...Umscheid
SHORT TERM...Umscheid
LONG TERM...Finch
AVIATION...Finch
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
512 AM CST Wed Jan 1 2014
...Update to snowfall forecast...
.SYNOPSIS...
ISSUED AT 339 AM CST WED JAN 1 2014
Water vapor loop during the overnight hours showed a digging
shortwave trough across eastern Wyoming...reaching northern Colorado
as of 09Z. This shortwave trough encompassed a much larger scale
gyre that was centered over southeastern Hudson Bay. In the lower
troposphere, temperatures were fairly mild on the High Plains with
850mb temperatures from +8 to +10C. Meanwhile, the very sharp
baroclinic zone at 850mb was found from northeastern Montana through
northeastern Nebraska per 00Z RAOB and RAP analysis. Surface
temperatures across Nebraska on the 09Z analysis ranged from 35F at
Scottsbluff to +8F at O`Neill on the other side of the front. Below
zero temperatures (degF) were not too far away into southeastern
South Dakota.
&&
.UPDATE...
ISSUED AT 504 AM CST WED JAN 1 2014
There seems to be enough of a signal in the most recent mesoscale
model solutions to bump up snowfall amounts in the northeast
counties (northeast of a Scott City to Jetmore to Pratt line). A
look at the 03Z run of the SREF Plumes for Hays indicates a mean
of all perturbations just under 2 inches. However, much of that is
influenced by the seemingly wet WRF-ARW core. The WRF-ARW
perturbations are clustered between 3 and 4 inches at Hays. While
we do not necessarily believe total snowfall will be quite that
high given the fast speed of the system, some brief moderate-high
snowfall rates as the 700mb zone of frontogenesis passes would
argue for at least an inch or two of final snowfall. As a result,
we have bumped up the snowfall just a bit to around an inch and a
half along I-70... and the half inch line down to roughly Scott
City-Jetmore-Pratt line. With the increased snowfall forecast, we
will have to think more about the blowing and drifting potential
as 18 to 22 knot sustained winds will add to reduced visibility
for a few hours this afternoon. We will hold off on issuing a
winter weather advisory with sub-two inch forecast amounts, but it
is something that the incoming day shift will need to monitor
closely.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 339 AM CST WED JAN 1 2014
As mentioned in the synopsis section, a sharp baroclinic zone was
found across Nebraska. As the mid-level shortwave trough moves
southeast into western Kansas today, some of this arctic air
residing in central Nebraska will advect southward on
northeast...and eventually due north winds. The problem in the
forecast for today is just how far southwest this arctic airmass
will reach. North-northwest winds at the surface near the Colorado
border will not be advecting in much of that arctic air at all (It
was still 31F in Douglas, WY and 35F in Scottsbluff, NE as of
09Z!). We foresee a fairly sharp temperature gradient across
western Kansas today. There is a rather high degree of uncertainty
in the temperature forecast west of Highway 283. The official
forecast will call for steady or falling temperatures through the
day northeast of roughly Dighton to Dodge City to Pratt. Northeast
of this line, there is a fairly high degree of confidence in the
temperature forecast...and that it will be very cold with
temperatures falling through the 20s...and into the mid to upper
teens potentially at Hays. Then there is the
Elkhart-Johnson-Syracuse corridor. This area, if they see any of
this arctic air at all, will be later in the day. This will allow
the Colorado border areas to warm well into the upper 30s to lower
40s. By early to mid afternoon, we could very well see a 30-degree
temperature gradient from southwest to northeast across the DDC
forecast area (from Elkhart to Hays).
Now on to the snow. Nothing much has really changed from previous
forecast thinking. The shortwave trough will be zipping southeast
quickly today, and there will only be a 2 to 4 hour period of light
to briefly moderate snow across the far northeastern zones (most
particularly, Hays-Victoria)...along the zone of strongest 700mb
frontogenesis. The best of this frontogenetic response at 700mb will
be just northeast of the DDC forecast area (across north-central
Kansas) as is indicated by the latest NAM12 and WRF runs. There
could be a brief period of some showery type snow along the Scott
City to Dodge City to Pratt corridor from midday to late afternoon
as a pocket of very slight potential instability develops in the mid
levels right near the 400-500mb potential vorticity anomaly. This
could put down a quickly quarter to half inch of snow in some
scattered spots along the Scott City-Dodge City-Pratt axis.
All of the snow and/or snow showers will be well east of the
southwest Kansas region by early this evening. Downslope
trajectories will resume overnight with a light westerly surface
wind developing especially along/west of Highway 83. Temperatures
should stabilize in the upper teens to lower 20s if not very slowly
rise toward 12Z. Across central Kansas, temperatures will likely
bottom out around +10F.
.LONG TERM...(Thursday through Tuesday)
ISSUED AT 348 AM CST WED JAN 1 2014
A warming trend will commence Thursday and Friday as the mid to
upper level flow becomes more zonal across the Rockies, and surface
pressures fall in the lee of the Rockies. Highs should make it
into the 40s in most places Thursday as the arctic air gets shunted
into eastern Kansas given the increasing low to mid level westerly
momentum. A progressive, positively tilted shortwave trough will
approach from the northwest by Saturday, and as one would expect with
a positively tilted system, a cold surge will pass through western
Kansas ahead of the feature. In spite of the cold advection, some
light snow is possible as the trough approaches, with only minor
accumulations of an inch or less expected. Then by Sunday, a lobe of
the polar vortex will rotate southeastward into the northern plains
and upper midwest. This will provide a glancing blow of arctic air
into Kansas for Sunday night into Monday, with moderating
temperatures by Tuesday and Wednesday into the 30s for highs as the
low level flow quickly becomes more westerly. The next upper
trough will approach Kansas by Wednesday and Thursday, but a lack
of deep moisture may preclude precipitation. However, if this
system is slower and more amplified, then some rain or snow would
be possible.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
ISSUED AT 1158 PM CST TUE DEC 31 2013
The next cold front is due between 10-12Z across the DDC, GCK, HYS
terminals. Behind the front, ceilings are expected to lower into
the MVFR range at anywhere from 1000 to 2000 foot broken or
overcast. Winds will the increase late morning and into the
afternoon from the north at 20 knots sustained with higher gusts.
The snow which is forecast will be light and be confined mainly to
the HYS terminal...where we will drop the visibility to about a
mile for a few hours during the heavier snow which really should
not accumulate much over an inch, if that.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 27 16 44 21 / 30 10 0 0
GCK 31 18 45 20 / 30 10 0 0
EHA 46 21 49 26 / 10 10 0 0
LBL 39 21 47 26 / 10 10 0 0
HYS 20 11 34 17 / 80 10 0 0
P28 30 17 40 19 / 20 10 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Umscheid
SYNOPSIS...Umscheid
SHORT TERM...Umscheid
LONG TERM...Finch
AVIATION...Umscheid
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1001 AM CST WED JAN 1 2014
.UPDATE...
ISSUED AT 1000 AM CST WED JAN 1 2014
ALLOWED THE WIND CHILL ADVISORY TO EXPIRE WITH THIS UPDATE...AS
WIND CHILLS WILL CONTINUE TO SLOWLY IMPROVE THROUGH THE LATE
MORNING AND AFTERNOON. HOWEVER...ANOTHER WIND CHILL ADVISORY MAY
BE NEEDED ACROSS THE NORTH AND CENTRAL TONIGHT. OTHERWISE...ADDED
A MENTION OF FLURRIES INTO THE AFTERNOON UNDER THE STRATUS.
UPDATE ISSUED AT 643 AM CST WED JAN 1 2014
UPDATED TO INCREASE PRECIPITATION CHANCES OVER THE NEXT FEW HOURS
AS THE BANDED SNOW TRANSLATES SOUTHEASTWARD THIS MORNING. KMOT
DROPPED TO 1 SM WITH SNOW EARLIER THIS MORNING...AND LARGE FLAKES
HAVE BEEN FALLING FOR SOME TIME IN BISMARCK. COVERAGE WAS
DETERMINED USING A COMBINATION OF SATELLITE...RADAR...AND SURFACE
OBSERVATIONS.
THE WIND CHILL ADVISORY STILL LOOKS GOOD...SO NO CHANGES THERE.
UPDATE
ISSUED AT 500 AM CST WED JAN 1 2014
QUICK UPDATE TO INCREASE POPS EARLY THIS MORNING. LATEST RAP AND
RADAR IMAGERY SUPPORT LIKELY TO CATEGORICAL POPS NORTHWEST AND
CENTRAL...EAST OF THE SFC TROUGH OVER MY WEST. NO OTHER CHANGES
WITH THIS UPDATE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CST WED JAN 1 2014
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE COLD
TEMPERATURES AND WIND CHILLS THROUGH THE PERIOD...ALONG WITH
LINGERING LIGHT SNOW THIS MORNING.
CURRENTLY...UPPER LEVEL RIDGE ACROSS THE WEST COAST EXTENDS NORTH
INTO ALASKA...WITH A DEEP UPPER LEVEL LOW OVER SOUTHEAST CANADA.
THIS RESULTS IN NORTHWEST FLOW ALOFT OVER THE NORTHERN
PLAINS...WITH MID LEVEL EMBEDDED ENERGY TRACKING SOUTHEAST ACROSS
THE LOCAL AREA. MID LEVEL IMPULSES COMBINED WITH CONTINUED
ISENTROPIC LIFT EAST OF A SFC TROUGH CURRENTLY POSITIONED OVER THE
FAR WESTERN DAKOTAS...MAINTAINS EXTENSIVE CLOUDINESS ACROSS WEST
AND CENTRAL NORTH DAKOTA...ALONG WITH AREAS OF LIGHT SNOW EAST OF
THE TROUGH AXIS. WHILE CLOUDS REMAIN THROUGH THE MORNING...CHANCES
FOR LIGHT SNOW ARE EXPECTED TO DIMINISH FROM WEST TO EAST NOW
THROUGH 18Z AS ENERGY ALOFT MOVES OUT OF THE REGION AND AS THE SFC
TROUGH MOVES SOUTH AND EAST DECREASING THE OVERRUNNING FLOW WITH
WINDS TRANSITIONING TO MORE OF A NORTHERLY COMPONENT.
BROAD HIGH PRESSURE DEVELOPS SOUTHWARD INTO THE REGION TODAY...AND
MAY RESULT IN PARTIAL CLEARING ACROSS THE NORTH. CLOUDS ARE FORECAST
TO LINGER SOUTH AND WESTWARD. CURRENT TEMPERATURES FROM 10 ABOVE
SOUTHWEST...SINGLE DIGITS BELOW CENTRAL...AND 10-15 BELOW EAST ARE
NOT EXPECTED TO RECOVER MUCH TODAY...WARMING BY ONLY 5 DEGREES OR
SO WITH THE COLD AIRMASS REMAINING OVER THE STATE.
CHANCES FOR LIGHT SNOW WILL REMAIN IN THE FORECAST WEST THIS
AFTERNOON INTO TONIGHT AS ANOTHER SFC TROUGH/FRONTAL BOUNDARY
DEVELOPS FROM NORTH CENTRAL MONTANA SOUTHEAST INTO WESTERN
NEBRASKA. THIS POSITION IS VERY SIMILAR TO THE PAST COUPLE OF
DAYS WHERE WE SAW ACCUMULATING LIGHT SNOW WEST INTO SOUTH
CENTRAL...WITH THE MAIN DIFFERENCE THIS TIME THE PLACEMENT OF
STRONG HIGH PRESSURE ACROSS EASTERN NORTH DAKOTA. THUS I EXPECT
THE SNOW TO BE CONFINED TO FAR WESTERN ND WITH STRONG SUBSIDENCE
IN CONTROL OVER THE EASTERN TWO THIRDS OF THE STATE. CLEAR TO
PARTLY CLOUDY SKIES ACROSS MY EASTERN ONE HALF TONIGHT COUPLED
WITH LIGHT WINDS WILL LEAD TO A VERY COLD NIGHT...WITH MORNING
LOWS ON THURSDAY 20-25 BELOW NORTHWEST...CENTRAL...AND EAST.
BALMY SOUTHWEST WHERE A LOW OF ZERO IS CURRENTLY FORECAST. WIND
CHILL HEADLINES WILL BE QUESTIONABLE AS WINDS MAY BE CALM WHERE
THE COLDEST TEMPERATURES ARE EXPECTED.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 350 AM CST WED JAN 1 2014
THE MAIN FOCUS OF TODAY`S FORECAST IS ON THE FRIDAY CLIPPER SYSTEM
AND ASSOCIATED FRIGID AIR MOVING INTO THE REGION ON SATURDAY.
MODELS/ENSEMBLES AGREE ON A GRADUAL WARMING TREND THROUGH
FRIDAY...WHEN PRE-CLIPPER WARM AIR ADVECTION DRIVES HIGHS INTO THE
LOW TO MID 30S. ASSOCIATED PRECIPITATION WILL LIKELY BE RAIN OR
SNOW. 00 UTC NAM/GFS/SREF BUFKIT SOUNDINGS ACROSS THE WEST SUPPORT
ONLY MINIMAL MELTING ALOFT...SINCE THE MAJORITY OF PRECIPITATION
FALLS AFTER THE COLD FRONTAL PASSAGE. LIQUID PRECIPITATION OF UP TO
0.1 INCH MEANS THAT EVEN IF IT IS ALL SNOW...ACCUMULATIONS WILL BE
MINIMAL.
THE ARCTIC AIR MASS FOLLOWING THIS CLIPPER WILL DROP LOW
TEMPERATURES DOWN TO AROUND -20F ON SUNDAY AND MONDAY NIGHTS. THIS
COLD WILL BE ACCOMPANIED BY WIND...SO RESULTING WIND CHILLS WILL BE
-40F TO -50F. IT IS WORTH NOTING THAT THE 00 UTC ECMWF SUPPORTS EVEN
COLDER AIR MOVING INTO THE REGION. A RETURN TO NEAR NORMAL
TEMPERATURES IS FORECAST BY THE MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY)
ISSUED AT 1000 AM CST WED JAN 1 2014
MVFR CONDITIONS IN LIGHT SNOW AND STRATUS WILL CONTINUE ACROSS
MUCH OF WESTERN AND CENTRAL NORTH DAKOTA INTO THE AFTERNOON.
EXPECT VFR CONDITIONS DEVELOPING TONIGHT INTO THURSDAY MORNING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SYNOPSIS...SCHECK
SHORT TERM...NH
LONG TERM...SCHECK
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
648 AM CST WED JAN 1 2014
.SYNOPSIS...
ISSUED AT 350 AM CST WED JAN 1 2014
THE LARGE SCALE PATTERN OF HIGH LATITUDE BLOCKING AND ARCTIC AIR
MOVING SOUTH INTO THE NORTHERN PLAINS AROUND A NEGATIVE HEIGHT
ANOMALY NEAR THE HUDSON BAY IS FORECAST TO CONTINUE THROUGH THE
PERIOD. MODELS/ENSEMBLES SUGGEST THAT THE ALASKA RIDGING MAY BREAK
DOWN AS THE MAIN BELT OF WESTERLIES BECOMES MORE ZONAL BY THE END
OF NEXT WEEK.
&&
.UPDATE...
ISSUED AT 643 AM CST WED JAN 1 2014
UPDATED TO INCREASE PRECIPITATION CHANCES OVER THE NEXT FEW HOURS
AS THE BANDED SNOW TRANSLATES SOUTHEASTWARD THIS MORNING. KMOT
DROPPED TO 1 SM WITH SNOW EARLIER THIS MORNING...AND LARGE FLAKES
HAVE BEEN FALLING FOR SOME TIME IN BISMARCK. COVERAGE WAS
DETERMINED USING A COMBINATION OF SATELLITE...RADAR...AND SURFACE
OBSERVATIONS.
THE WIND CHILL ADVISORY STILL LOOKS GOOD...SO NO CHANGES THERE.
UPDATE
ISSUED AT 500 AM CST WED JAN 1 2014
QUICK UPDATE TO INCREASE POPS EARLY THIS MORNING. LATEST RAP AND
RADAR IMAGERY SUPPORT LIKELY TO CATEGORICAL POPS NORTHWEST AND
CENTRAL...EAST OF THE SFC TROUGH OVER MY WEST. NO OTHER CHANGES
WITH THIS UPDATE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CST WED JAN 1 2014
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE COLD
TEMPERATURES AND WIND CHILLS THROUGH THE PERIOD...ALONG WITH
LINGERING LIGHT SNOW THIS MORNING.
CURRENTLY...UPPER LEVEL RIDGE ACROSS THE WEST COAST EXTENDS NORTH
INTO ALASKA...WITH A DEEP UPPER LEVEL LOW OVER SOUTHEAST CANADA.
THIS RESULTS IN NORTHWEST FLOW ALOFT OVER THE NORTHERN
PLAINS...WITH MID LEVEL EMBEDDED ENERGY TRACKING SOUTHEAST ACROSS
THE LOCAL AREA. MID LEVEL IMPULSES COMBINED WITH CONTINUED
ISENTROPIC LIFT EAST OF A SFC TROUGH CURRENTLY POSITIONED OVER THE
FAR WESTERN DAKOTAS...MAINTAINS EXTENSIVE CLOUDINESS ACROSS WEST
AND CENTRAL NORTH DAKOTA...ALONG WITH AREAS OF LIGHT SNOW EAST OF
THE TROUGH AXIS. WHILE CLOUDS REMAIN THROUGH THE MORNING...CHANCES
FOR LIGHT SNOW ARE EXPECTED TO DIMINISH FROM WEST TO EAST NOW
THROUGH 18Z AS ENERGY ALOFT MOVES OUT OF THE REGION AND AS THE SFC
TROUGH MOVES SOUTH AND EAST DECREASING THE OVERRUNNING FLOW WITH
WINDS TRANSITIONING TO MORE OF A NORTHERLY COMPONENT.
BROAD HIGH PRESSURE DEVELOPS SOUTHWARD INTO THE REGION TODAY...AND
MAY RESULT IN PARTIAL CLEARING ACROSS THE NORTH. CLOUDS ARE FORECAST
TO LINGER SOUTH AND WESTWARD. CURRENT TEMPERATURES FROM 10 ABOVE
SOUTHWEST...SINGLE DIGITS BELOW CENTRAL...AND 10-15 BELOW EAST ARE
NOT EXPECTED TO RECOVER MUCH TODAY...WARMING BY ONLY 5 DEGREES OR
SO WITH THE COLD AIRMASS REMAINING OVER THE STATE.
CHANCES FOR LIGHT SNOW WILL REMAIN IN THE FORECAST WEST THIS
AFTERNOON INTO TONIGHT AS ANOTHER SFC TROUGH/FRONTAL BOUNDARY
DEVELOPS FROM NORTH CENTRAL MONTANA SOUTHEAST INTO WESTERN
NEBRASKA. THIS POSITION IS VERY SIMILAR TO THE PAST COUPLE OF
DAYS WHERE WE SAW ACCUMULATING LIGHT SNOW WEST INTO SOUTH
CENTRAL...WITH THE MAIN DIFFERENCE THIS TIME THE PLACEMENT OF
STRONG HIGH PRESSURE ACROSS EASTERN NORTH DAKOTA. THUS I EXPECT
THE SNOW TO BE CONFINED TO FAR WESTERN ND WITH STRONG SUBSIDENCE
IN CONTROL OVER THE EASTERN TWO THIRDS OF THE STATE. CLEAR TO
PARTLY CLOUDY SKIES ACROSS MY EASTERN ONE HALF TONIGHT COUPLED
WITH LIGHT WINDS WILL LEAD TO A VERY COLD NIGHT...WITH MORNING
LOWS ON THURSDAY 20-25 BELOW NORTHWEST...CENTRAL...AND EAST.
BALMY SOUTHWEST WHERE A LOW OF ZERO IS CURRENTLY FORECAST. WIND
CHILL HEADLINES WILL BE QUESTIONABLE AS WINDS MAY BE CALM WHERE
THE COLDEST TEMPERATURES ARE EXPECTED.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 350 AM CST WED JAN 1 2014
THE MAIN FOCUS OF TODAY`S FORECAST IS ON THE FRIDAY CLIPPER SYSTEM
AND ASSOCIATED FRIGID AIR MOVING INTO THE REGION ON SATURDAY.
MODELS/ENSEMBLES AGREE ON A GRADUAL WARMING TREND THROUGH
FRIDAY...WHEN PRE-CLIPPER WARM AIR ADVECTION DRIVES HIGHS INTO THE
LOW TO MID 30S. ASSOCIATED PRECIPITATION WILL LIKELY BE RAIN OR
SNOW. 00 UTC NAM/GFS/SREF BUFKIT SOUNDINGS ACROSS THE WEST SUPPORT
ONLY MINIMAL MELTING ALOFT...SINCE THE MAJORITY OF PRECIPITATION
FALLS AFTER THE COLD FRONTAL PASSAGE. LIQUID PRECIPITATION OF UP TO
0.1 INCH MEANS THAT EVEN IF IT IS ALL SNOW...ACCUMULATIONS WILL BE
MINIMAL.
THE ARCTIC AIR MASS FOLLOWING THIS CLIPPER WILL DROP LOW
TEMPERATURES DOWN TO AROUND -20F ON SUNDAY AND MONDAY NIGHTS. THIS
COLD WILL BE ACCOMPANIED BY WIND...SO RESULTING WIND CHILLS WILL BE
-40F TO -50F. IT IS WORTH NOTING THAT THE 00 UTC ECMWF SUPPORTS EVEN
COLDER AIR MOVING INTO THE REGION. A RETURN TO NEAR NORMAL
TEMPERATURES IS FORECAST BY THE MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 643 AM CST WED JAN 1 2014
VFR TO MVFR BKN-OVC CIGS ARE EXPECTED THROUGH THE FORECAST
PERIOD. THE HIGHER TERRAIN OF SOUTHWEST NORTH DAKOTA...INCLUDING
KDIK...WILL EXPERIENCE IFR CIGS THIS MORNING...BEFORE IMPROVING
LATER TODAY. WILL SEE OCCASIONAL LIGHT SNOW AT ALL TERMINALS EXCEPT
KDIK THROUGH THE MORNING HOURS. A PERIOD OF IFR VIS WILL BE POSSIBLE
THROUGH 18Z. SKIES WILL TREND SCT NORTH AND EAST AFTER 06Z FOR KMOT
AND KJMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 11 AM CST THIS MORNING FOR NDZ002>005-
011>013-022-023-025-036-037-047-048-050-051.
&&
$$
UPDATE...SCHECK
SYNOPSIS...SCHECK
SHORT TERM...NH
LONG TERM...SCHECK
AVIATION...NH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
459 AM CST WED JAN 1 2014
.SYNOPSIS...
ISSUED AT 350 AM CST WED JAN 1 2014
THE LARGE SCALE PATTERN OF HIGH LATITUDE BLOCKING AND ARCTIC AIR
MOVING SOUTH INTO THE NORTHERN PLAINS AROUND A NEGATIVE HEIGHT
ANOMALY NEAR THE HUDSON BAY IS FORECAST TO CONTINUE THROUGH THE
PERIOD. MODELS/ENSEMBLES SUGGEST THAT THE ALASKA RIDGING MAY BREAK
DOWN AS THE MAIN BELT OF WESTERLIES BECOMES MORE ZONAL BY THE END
OF NEXT WEEK.
&&
.UPDATE...
ISSUED AT 500 AM CST WED JAN 1 2014
QUICK UPDATE TO INCREASE POPS EARLY THIS MORNING. LATEST RAP AND
RADAR IMAGERY SUPPORT LIKELY TO CATEGORICAL POPS NORTHWEST AND
CENTRAL...EAST OF THE SFC TROUGH OVER MY WEST. NO OTHER CHANGES
WITH THIS UPDATE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CST WED JAN 1 2014
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE COLD
TEMPERATURES AND WIND CHILLS THROUGH THE PERIOD...ALONG WITH
LINGERING LIGHT SNOW THIS MORNING.
CURRENTLY...UPPER LEVEL RIDGE ACROSS THE WEST COAST EXTENDS NORTH
INTO ALASKA...WITH A DEEP UPPER LEVEL LOW OVER SOUTHEAST CANADA.
THIS RESULTS IN NORTHWEST FLOW ALOFT OVER THE NORTHERN
PLAINS...WITH MID LEVEL EMBEDDED ENERGY TRACKING SOUTHEAST ACROSS
THE LOCAL AREA. MID LEVEL IMPULSES COMBINED WITH CONTINUED
ISENTROPIC LIFT EAST OF A SFC TROUGH CURRENTLY POSITIONED OVER THE
FAR WESTERN DAKOTAS...MAINTAINS EXTENSIVE CLOUDINESS ACROSS WEST
AND CENTRAL NORTH DAKOTA...ALONG WITH AREAS OF LIGHT SNOW EAST OF
THE TROUGH AXIS. WHILE CLOUDS REMAIN THROUGH THE MORNING...CHANCES
FOR LIGHT SNOW ARE EXPECTED TO DIMINISH FROM WEST TO EAST NOW
THROUGH 18Z AS ENERGY ALOFT MOVES OUT OF THE REGION AND AS THE SFC
TROUGH MOVES SOUTH AND EAST DECREASING THE OVERRUNNING FLOW WITH
WINDS TRANSITIONING TO MORE OF A NORTHERLY COMPONENT.
BROAD HIGH PRESSURE DEVELOPS SOUTHWARD INTO THE REGION TODAY...AND
MAY RESULT IN PARTIAL CLEARING ACROSS THE NORTH. CLOUDS ARE FORECAST
TO LINGER SOUTH AND WESTWARD. CURRENT TEMPERATURES FROM 10 ABOVE
SOUTHWEST...SINGLE DIGITS BELOW CENTRAL...AND 10-15 BELOW EAST ARE
NOT EXPECTED TO RECOVER MUCH TODAY...WARMING BY ONLY 5 DEGREES OR
SO WITH THE COLD AIRMASS REMAINING OVER THE STATE.
CHANCES FOR LIGHT SNOW WILL REMAIN IN THE FORECAST WEST THIS
AFTERNOON INTO TONIGHT AS ANOTHER SFC TROUGH/FRONTAL BOUNDARY
DEVELOPS FROM NORTH CENTRAL MONTANA SOUTHEAST INTO WESTERN
NEBRASKA. THIS POSITION IS VERY SIMILAR TO THE PAST COUPLE OF
DAYS WHERE WE SAW ACCUMULATING LIGHT SNOW WEST INTO SOUTH
CENTRAL...WITH THE MAIN DIFFERENCE THIS TIME THE PLACEMENT OF
STRONG HIGH PRESSURE ACROSS EASTERN NORTH DAKOTA. THUS I EXPECT
THE SNOW TO BE CONFINED TO FAR WESTERN ND WITH STRONG SUBSIDENCE
IN CONTROL OVER THE EASTERN TWO THIRDS OF THE STATE. CLEAR TO
PARTLY CLOUDY SKIES ACROSS MY EASTERN ONE HALF TONIGHT COUPLED
WITH LIGHT WINDS WILL LEAD TO A VERY COLD NIGHT...WITH MORNING
LOWS ON THURSDAY 20-25 BELOW NORTHWEST...CENTRAL...AND EAST.
BALMY SOUTHWEST WHERE A LOW OF ZERO IS CURRENTLY FORECAST. WIND
CHILL HEADLINES WILL BE QUESTIONABLE AS WINDS MAY BE CALM WHERE
THE COLDEST TEMPERATURES ARE EXPECTED.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 350 AM CST WED JAN 1 2014
THE MAIN FOCUS OF TODAY`S FORECAST IS ON THE FRIDAY CLIPPER SYSTEM
AND ASSOCIATED FRIGID AIR MOVING INTO THE REGION ON SATURDAY.
MODELS/ENSEMBLES AGREE ON A GRADUAL WARMING TREND THROUGH
FRIDAY...WHEN PRE-CLIPPER WARM AIR ADVECTION DRIVES HIGHS INTO THE
LOW TO MID 30S. ASSOCIATED PRECIPITATION WILL LIKELY BE RAIN OR
SNOW. 00 UTC NAM/GFS/SREF BUFKIT SOUNDINGS ACROSS THE WEST SUPPORT
ONLY MINIMAL MELTING ALOFT...SINCE THE MAJORITY OF PRECIPITATION
FALLS AFTER THE COLD FRONTAL PASSAGE. LIQUID PRECIPITATION OF UP TO
0.1 INCH MEANS THAT EVEN IF IT IS ALL SNOW...ACCUMULATIONS WILL BE
MINIMAL.
THE ARCTIC AIR MASS FOLLOWING THIS CLIPPER WILL DROP LOW
TEMPERATURES DOWN TO AROUND -20F ON SUNDAY AND MONDAY NIGHTS. THIS
COLD WILL BE ACCOMPANIED BY WIND...SO RESULTING WIND CHILLS WILL BE
-40F TO -50F. IT IS WORTH NOTING THAT THE 00 UTC ECMWF SUPPORTS EVEN
COLDER AIR MOVING INTO THE REGION. A RETURN TO NEAR NORMAL
TEMPERATURES IS FORECAST BY THE MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 350 AM CST WED JAN 1 2014
VFR TO MVFR BKN-OVC CIGS ARE EXPECTED THROUGH THE FORECAST
PERIOD. THE HIGHER TERRAIN OF SOUTHWEST NORTH DAKOTA...INCLUDING
KDIK...WILL EXPERIENCE IFR CIGS AT TIME. WILL SEE OCCASIONAL LIGHT
SNOW AT ALL TERMINALS EXCEPT KDIK THROUGH THE MORNING HOURS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 11 AM CST THIS MORNING FOR NDZ002>005-
011>013-022-023-025-036-037-047-048-050-051.
&&
$$
UPDATE...NH
SYNOPSIS...SCHECK
SHORT TERM...NH
LONG TERM...SCHECK
AVIATION...NH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
416 AM MST WED JAN 1 2014
.SHORT TERM...(NEW YEARS DAY THROUGH FRIDAY)
ISSUED AT 410 AM MST WED JAN 1 2014
KCYS 88D RETURNS ALONG WITH AREA METARS SHOW THAT ALMOST ALL AREAS
ARE OR HAVE ALREADY SEEN A PERIOD OF LIGHT SNOW THIS MORNING. MOST
AREAS OUTSIDE OF THE MOUNTAINS HAVE RECEIVED FROM A TRACE TO UP TO A
COUPLE OF INCHES. 10Z SFC ANALYSIS SHOWS LOW PRESSURE DEEPENING
ACROSS THE ERN COLORADO PLAINS WITH THE FRONT REACHING A DEPTH OF
AROUND 6 KFT AGL. SATELLITE PIX SHOW BAROCLINIC LEAF FORMING FROM
THE FRONT RANGE EAST ACROSS CENTRAL PLAINS AS A WELL DEFINED
SHORTWAVE AND H3 JET STREAK MOVING INTO WRN WYOMING. LATEST MODELS
CONTINUE TO PAINT THE BEST QG VERTICAL VELOCITIES ASSOCIATED WITH
THE SYNOPTIC ASCENT AHEAD OF THE SHORTWAVE PEAKING OVER THE AREA
DURING THE PRE-DAWN HOURS TODAY. SNOWFALL HAS BEEN AIDED BY LEFT
EXIT REGION JET SUPPORT...AS WELL AS EVIDENT CSI ATOP THE LLVL
FRONTAL INVERSION. AS A RESULT...WILL SEE THIS PERIOD OF LIGHT
SNOWFALL TO CONTINUE THROUGH THE REST OF THE MORNING
HOURS...ALTHOUGH WOULD EXPECT TO SEE INTENSITY AND COVERAGE
GRADUALLY DIMINISH THROUGH THE MORNING. WILL SEE PERHAPS AN
ADDITIONAL INCH OR SO OVER LOWER ELEVATIONS. THE SNOWY/SIERRA MADRE
RANGES HAVE FARED BETTER WITH GENERALLY 4 TO 8 INCHES ALREADY
OBSERVED. WILL CONTINUE THE WINTER WEATHER ADVISORY FOR THESE AREAS
AS ANOTHER 2 TO 4 INCHES WILL BE LIKELY. SHORTWAVE AND H3 JET AXIS
SHIFTS EAST THIS AFTERNOON BRINGING AN END TO SNOW CHANCES WEST TO
EAST. WILL BE NOTICEABLY COOLER TODAY IN CAA BEHIND FROPA. SO ONLY
EXPECT HIGHS TO REACH THE 30S TODAY.
HEIGHTS RISE RAPIDLY ON THURSDAY AS TRANSITORY RIDGING MOVES THRU.
MODELS DO STILL SHOW A WEAK SHORTWAVE EMBEDDED WITHIN THIS RIDGE
MOVING THRU ON THURSDAY. ALTHOUGH THE TREND HAS BEEN WEAKER OVER THE
PAST SEVERAL RUNS. IT WILL BE DRY...BUT WILL PRODUCE INCREASING
CLOUDS. TEMPERATURES WILL WARM FOR THURSDAY ESPECIALLY ACROSS
EXTREME SOUTHEAST WYOMING AND THE SOUTHERN NEBRASKA PANHANDLE WHERE
HIS WILL RISE INTO THE MID 40S.
LLVL GRADIENT LOOKS TO TIGHTEN A BIT EARLIER THAN EARLY MODELS
SHOWED...NOW DOING SO THURSDAY NIGHT AND FRIDAY. KCAG-KCPR GRADIENTS
BEGIN TO INFLATE TO BETWEEN 50-60 METERS AS EARLY AS 06Z FRIDAY. H7
WIND PROGS OF 50 TO 60 KNOTS WILL YIELD A GOOD CHANCE FOR THE NEXT
HIGH WIND EVENT ACROSS AT LEAST FOR PORTIONS OF SOUTHEAST WYOMING.
ADIABATIC WARMING FROM DOWNSLOPING CONDITIONS WILL RESULT IN HIGH
TEMPERATURES ON FRIDAY BOOSTING INTO THE 50S FOR MOST LOCATIONS EAST
OF THE LARAMIE RANGE. THE NEXT FRONT WILL APPROACH FROM THE
NORTHWEST LATE IN THE PERIOD. SO FOR NOW HAVE KEPT SNOW CHANCES
CONFINED TO THE HIER TERRAIN.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 410 AM MST WED JAN 1 2014
STRONG WESTERLY WINDS WILL CONTINUE OVER MUCH OF SOUTHEAST WYOMING
THROUGH EARLY FRIDAY NIGHT AS THE GFS SHOWS 700MB WINDS OF AROUND
50 KTS AHEAD OF THE SHORTWAVE. FROPA IS LATE FRIDAY NIGHT WITH
SCATTERED SNOW SHOWERS BEHIND IT. TEMPS WILL BE QUITE A BIT COLDER
ON SAT AS 700MB TEMPS DROP TO -15C. BELOW NORMAL TEMPS WILL
CONTINUE SUN AND MON AS STRONG NORTHWESTERLY FLOW ALOFT CONTINUES
ACROSS THE NORTHERN INTERMOUNTAIN WEST AND NORTHERN PLAINS.
SECONDARY SURGE OF COLD AIR PUSHES SOUTHWARD ON SUN NIGHT AND MON.
THIS IS THE COLDEST AIRMASS AND IS ASSOCIATED WITH A STRONG SFC
HIGH. THE GFS SHOWS 700MB TEMPS OF -25C JUST OFF TO THE NORTHEAST
OF THE CWA WITH -30C IN THE DAKOTAS BY 12Z MON. THUS...IT HAS THE
POTENTIAL TO BE SOME OF THE COLDEST TEMPS OF THE SEASON. KEPT
SLIGHT CHANCE POPS ACROSS THE NORTHEASTERN ZONES ON SUN AND MON IN
THE WEAK LLVL UPSLOPE. FLOW BECOMES MORE ZONAL BY TUES AND TEMPS
BEGIN TO MODERATE AS THE SFC HIGH SLIDES EASTWARD AND IS REPLACED
BY WEAK SFC TROUGHING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY EVENING)
ISSUED AT 1040 PM MST TUE DEC 31 2013
LATEST RADAR SHOWING AREA OF SNOW DROPPING SOUTH LATE THIS
EVENING. CHADRON ALREADY IFR AND LATEST HRRR FORECAST SHOWING THIS
IFR AREA DROPPING SOUTH INTO THE SOUTHERN PANHANDLE AS THE MORNING
PROGRESSES. SNOW ALSO IMPACTING KRWL AND KLAR AROUND THE 09Z
TIME FRAME AND CONTINUING THROUGH 18Z.
&&
.FIRE WEATHER...
ISSUED AT 410 AM MST WED JAN 1 2014
FIRE WEATHER CONCERNS WILL BE MINIMAL THROUGH EARLY NEXT WEEK. A
WEAK DISTURBANCE WILL BRING LIGHT SNOW TO THE DISTRICTS...WITH UP TO
A COUPLE OF INCHES DURING THE MORNING HOURS. OF COURSE...MOUNTAIN
LOCATIONS WILL SEE HIGHER AMOUNTS. COOLER TEMPERATURES TODAY WILL BE
FOLLOWED UP BY A WARM-UP THROUGH FRIDAY. STRONG WINDS WILL AGAIN
MAKE A RETURN TO THE REGION ON FRIDAY. THE NEXT FRONT WILL BE DUE IN
FOR FRIDAY NIGHT AND SATURDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY UNTIL 11 AM MST THIS MORNING FOR WYZ112-
114.
NE...NONE.
&&
$$
SHORT TERM...HAHN
LONG TERM...FINCH
AVIATION...CLAYCOMB
FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS RENO NV
149 PM PST WED JAN 1 2014
.SYNOPSIS...
MILD DAYTIME TEMPERATURES AND VALLEY INVERSIONS WILL CONTINUE FOR
THE FIRST FEW DAYS OF JANUARY. A COLD FRONT WILL BRING LIGHT EAST
WINDS AND COOLER TEMPERATURES FOR THE WEEKEND BUT NO PRECIPITATION.
IN FACT, NO SIGNIFICANT STORMS ARE EXPECTED THROUGH NEXT WEEK.
ALTHOUGH A FEW LIGHT SNOW SHOWERS ARE POSSIBLE TUESDAY WITH A
QUICK MOVING AREA OF LOW PRESSURE.
&&
.SHORT TERM...
NO SUBSTANTIAL CHANGES TO THE ONGOING FORECAST TODAY. RIDGING
ALOFT THROUGH TOMORROW WILL YIELD CONTINUED INVERSIONS IN THE
LOWER VALLEYS. WITH NO SNOW COVER AND PERIODS OF SUNSHINE, THESE
INVERSIONS ARE NOT SUPER STRONG. FORECAST SOUNDINGS DO SHOW WEAK
MIXING TO ~1000 FT AGL TODAY/TOMORROW WHICH MAY HELP DISPERSE
POLLUTANTS/HAZE A LITTLE.
FAST MOVING TROF SWINGS INTO THE EASTERN GREAT BASIN FRIDAY WHICH
SHOULD HELP ERODE INVERSIONS IN THE AFTERNOON DUE TO COOLER TEMPS
ALOFT AND SLIGHTLY INCREASED WINDS. HIGHS HAVE THE POTENTIAL TO BE
IN THE 55-60 RANGE ALONG THE SIERRA FRONT BUT CONFIDENCE IS ONLY
MEDIUM - DEPENDS ON HOW QUICKLY INVERSIONS ARE MIXED OUT. COOLER
AIR WORKS INTO THE REGION FRI NIGHT AND SATURDAY WITH A NOTICEABLE
DROP IN TEMPS. VALLEY INVERSIONS WILL BE BACK - BUT LIGHT EAST
FLOW WILL HELP KEEP LOW LEVELS MIXED TO ABOUT 7000-7500 FT MSL.
THERE MAY BE SOME SPOTS OF FZFG LATE TONIGHT IN THE FALLON/LOVELOCK
VICINITIES. CONFIDENCE IS LOW DUE TO CONFLICTING INGREDIENTS -
SOME HIGH CLOUDS ARE FORECAST TO STREAM INTO THE AREA BUT FORECAST
SOUNDINGS AND HRRR GUIDANCE POINT TO RENEWED FOG DEVELOPMENT
TOWARD DAYBREAK WITH FAVORABLE MOISTURE PROFILES IN THE BOUNDARY
LAYER. CS
&&
.LONG TERM...SUNDAY THROUGH WEDNESDAY...
LATEST MEDIUM RANGE GUIDANCE CONTINUES TO FAVOR KEEPING THE
BLOCKING RIDGE NEAR THE WEST COAST THROUGH THE MIDDLE OF NEXT
WEEK, DECREASING THE CHANCE OF A TRUE PACIFIC STORM REACHING THE
SIERRA. SOME WEAK SHORTWAVE ENERGY IS STILL PROJECTED TO MOVE INTO
THE REGION FROM THE NORTHWEST TUESDAY AND TUESDAY NIGHT AS THE
RIDGE AXIS DRIFTS A BIT FARTHER OFFSHORE, BUT MOISTURE APPEARS TO
BE LIMITED WITH THIS WEATHER SYSTEM.
FOR SUNDAY, THE INVERSION IS PROJECTED TO WEAKEN COMPARED TO
SATURDAY, ALLOWING FOR A FEW MORE DEGREES OF RECOVERY IN MOST OF
THE REGION WITH LIMITED AREAS OF CIRRUS COVERAGE. DAYTIME MAX
TEMPS SHOULD BE NEAR 50 DEGREES FOR MUCH OF WESTERN NV AND THE
SIERRA VALLEYS, EXCEPT A FEW DEGREES COOLER IN THE WEST CENTRAL NV
BASIN WHERE INVERSION WILL BE MORE PERSISTENT.
FOR MONDAY, HAVE TRENDED TEMPS DOWN A FEW DEGREES AS RIDGE
FLATTENS BUT A THICK LAYER OF CIRRUS IS FORECAST TO SPREAD ACROSS
THE REGION DURING THE DAY. EARLIER THIS WEEK, A SIMILAR PATTERN
OCCURRED WHICH RESULTED IN MAX TEMPS BEING SEVERAL DEGREES COOLER
THAN EXPECTED DUE TO THE WIDESPREAD CLOUD COVER.
ON TUESDAY, AS MENTIONED ABOVE A WEAK SHORTWAVE PASSAGE WITH
LIMITED MOISTURE IS STILL INDICATED ON BOTH THE GFS AND ECMWF. AIR
MASS IS LIKELY TO BE COOL ENOUGH FOR MAINLY SNOW SHOWERS, BUT
AMOUNTS WILL BE VERY LIGHT AND LIMITED TO AREAS NORTH OF I-80. THE
POTENTIAL FOR PRECIP DECREASES ON WEDNESDAY BEHIND THE SHORTWAVE,
EXCEPT FOR A FEW VERY LIGHT SNOW SHOWERS NEAR THE OREGON BORDER
WHERE SOME WARM ADVECTION ALOFT IS POSSIBLE. TEMPS WILL BE NEAR
SEASONAL NORMALS WITH HIGHS MAINLY IN THE 40S BOTH DAYS, WITH LOWS
GENERALLY IN THE TEENS AND 20S.
LATER NEXT WEEK, THE PREVAILING STORM TRACK APPEARS TO BE
FAVORING INCREASED CHANCES FOR MEANINGFUL PRECIP IN THE PACIFIC
NORTHWEST, BUT STILL DRY IN THE SIERRA. THE MEDIUM RANGE GUIDANCE
HAS VARIED WIDELY FROM RUN TO RUN SO THE POSSIBILITY STILL EXISTS
FOR THE PACIFIC MOISTURE TO BE DIRECTED FARTHER SOUTH INTO
CALIFORNIA, BUT CONFIDENCE REMAINS LOW IN BREAKING OUT OF THIS DRY
WEATHER PATTERN THROUGH THE FIRST THIRD OF THE MONTH. MJD
&&
.AVIATION...
PRIMARILY VFR FOR AREA TAF SITES THROUGH THURSDAY WITH JUST
PERIODS OF SCT-BKN HIGH CLOUDS. HAZE AT RNO/CXP WILL CONTINUE BUT
NOT ENOUGH TO RESTRICT VISIBILITIES BELOW 6SM. IFR FZFG MAY
DEVELOP AT LOL/NFL FROM 12-16Z/THURSDAY BUT CONFIDENCE IS LOW DUE
TO HIGH CLOUDS POTENTIALLY LIMITING FOG FORMATION. CS
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1008 AM MST WED JAN 1 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 443 AM MST WED JAN 1 2014
THE UPPER LEVEL TROF WILL GLANCE THROUGH NORTHERN AND EASTERLY
COLORADO TODAY SENDING A COLD FRONT THROUGH THE REGION. MOUNTAINS
AREAS WILL SEE AT LEAST A SLIGHT CHANCE FOR SNOW...WITH THE CENTRAL
MOUNTAINS PICKING UP SOME LIGHT ACCUMULATIONS DUE TO BETTER PROXIMITY
TO DYNAMICS THIS MORNING...AND CONTINUED NORTHWESTERLY OROGRAPHIC
FLOW INTO THIS EVENING. MODELS ARE GIVING AN ADDITIONAL 1 TO 3
INCHES OF ACCUMULATION FOR THAT AREA. STILL A VARIETY OF SOLUTIONS FOR
THE SOUTHEAST PLAINS AS FAR AS PRECIPITATION GOES WITH NAM12 KEEPING
ALL THE SNOW TO THE NORTH OF THE FORECAST AREA. GFS AND ECMWF OFFER
UP MORE WIDESPREAD PRECIPITATION...ALBEIT LIGHT...ACROSS THE
SOUTHEAST MOUNTAINS AND PLAINS TODAY. RAP13 AND HRRR SEEM TO OFFER
A CONSENSUS SOLUTION WITH LOCATIONS MAINLY ACROSS NORTHERN EL PASO
COUNTY OUT TOWARDS KIOWA COUNTY PICKING UP SOME LIGHT SNOW. HAVE
INTRODUCED SOME SCATTERED POPS FOR THESE AREAS...EVEN A BRIEF LIKELY
POP FOR THE NORTHEAST UPSLOPE FAVORED REGIONS OF TELLER AND NRN EL
PASO RIGHT AROUND 15Z. ANY ACCUMULATIONS WILL PROBABLY REMAIN UNDER
AN INCH.
THE ASSOCIATED COLD FRONT WILL DROP THROUGH THE REGION EARLY THIS
MORNING BRINGING SOME GUSTY NORTH WINDS TO ALL OF THE SOUTHEAST
PLAINS...ALONG WITH COLDER TEMPERATURES. CAA WILL BE OFFSET SOME BY
THE GUSTY WINDS AND MIXING...SO HIGHS WILL PROBABLY TOP OUT AROUND
NOON...THEN STAY STEADY BEFORE FALLING AGAIN TOWARDS EVENING. HAVE
KEPT HIGHS IN THE 40S FOR THE PLAINS. MOUNTAIN AREAS WILL LARGELY
TOP OUT IN THE 20S AND LOWER 30S...THOUGH HIGHER PEAKS WILL ONLY
MAKE THE TEENS. OTHER CONUNDRUM WILL BE TEMPERATURES FOR ALAMOSA.
ON THE ONE HAND...THE UPPER TROF HAS THE POTENTIAL TO BRING SOME
MIXING TO THE SAN LUIS VALLEY ALLOWING TEMPERATURES TO WARM INTO THE
20S. ON THE OTHER HAND IF INVERSIONS ARE TOO STRONG THEN HIGHS
COULD REMAIN IN THE TEENS. HAVE GONE A LITTLE WARMER THAN YESTERDAY
ESPECIALLY ALONG VALLEY EDGES WHERE MIXING IS MORE LIKELY TO OCCUR.
TONIGHT...DRY AIR WILL SPREAD IN BEHIND THE DEPARTING SYSTEM
ALLOWING FOR EFFICIENT RADIATIONAL COOLING. MIN TEMPERATURES IN
KALS COULD APPROACH -20 BASED ON MET GUIDANCE...WHICH DOES NOT SEEM
TOO UNREASONABLE...THOUGH SPLIT THE DIFFERENCE BETWEEN MET AND
SLIGHTLY WARMER MAV GUIDANCE FOR NOW. ELSEWHERE...TEENS LOOK LIKELY
FOR THE LOWER ARKANSAS RIVER VALLEY WHILE LEE TROFING AND SOME
WESTERLY DRAINAGE WINDS SHOULD KEEP LOWS IN THE 20S ALONG THE LOWER
SLOPES OF THE SE MTS/ADJACENT PLAINS WEST OF I-25. GIVEN HOW DRY
THE ATMOS IS ABOVE THE SURFACE WILL REFRAIN FROM INTRODUCING FOG
INTO THE SAN LUIS VALLEY AS PROBABILITY LOOKS LOW AT THIS POINT. -KT
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 443 AM MST WED JAN 1 2014
.THURSDAY AND FRIDAY...FLOW ALOFT BECOMES MORE WESTERLY AHEAD OF
THE NEXT DISTURBANCE APPROACHING FROM THE NORTHWEST. TEMPERATURES
ALOFT WARM TO AROUND +2C BY FRIDAY. WITH LEE TROUGH DEVELOPING
OVER THE PLAINS...ANTICIPATE TEMPERATURES APPROACHING 60F ON THE
PLAINS ON FRIDAY. OVER THE MOUNTAINS AND HIGH VALLEYS...IT WILL BE DRY
WITH SOME LIGHT SNOW POSSIBLY REACHING THE MOUNTAINS OF LAKE
COUNTY BY LATE FRIDAY. TEMPERATURES WILL BE MILD...EXCEPT FOR THE
SAN LUIS VALLEY WHERE COLD AIR WILL REMAIN TRAPPED.
.SATURDAY THROUGH MONDAY...ONE DISTURBANCE PASSES OVER REGION ON
SATURDAY WITH A SECONDARY DISTURBANCE PASSING MOSTLY TO THE NORTHEAST
OF THE REGION ON MONDAY. THERE WILL BE A COLD ASSOCIATED WITH EACH
DISTURBANCE. THE REGION WILL BE ON THE WESTERN FRINGES OF SOME
ARCTIC AIR...AND THE MAIN CHALLENGE IS THE AMOUNT OF COOLING
BEHIND THE FRONT. MODELS HAVE GENERALLY BEEN TRENDING TOWARDS
HAVING THE CORE OF THE COLD AIR STAYING FURTHER TO THE NORTHEAST
OF THE REGION...AND ONLY WENT WITH MODEST COOLING BEHIND THE
FRONTS. IF THE COLD AIR MOVES SLIGHTLY FURTHER TO THE WEST...THEN
HIGHS COLD EASILY BE 10F COOLER THAN WHAT IS CURRENTLY IN THE
GRIDS. A POCKET OF COLD AIR ALOFT WILL ACCOMPANY THE FRONTAL
PASSAGE ON SATURDAY. WITH THE WEAK STABILITY...THERE IS A CHANCE
FOR THE LIGHT SNOW BEHIND THE COLD FRONT OVER THE PLAINS AND
EASTERN MOUNTAINS. OVER THE REMAINING MOUNTAINS AND HIGH
VALLEYS...LIGHT SNOW WILL MOSTLY LIKELY ON SATURDAY WITH THE BEST
CHANCES IN MOUNTAINS OF LAKE AND CHAFFEE COUNTIES. ANTICIPATE AMOUNTS
WILL STAY BELOW ADVISORY CRITERIA. THE DISTURBANCE ON MONDAY WILL
BE FURTHER TO THE NORTHEAST RESULTING IN LESSER CHANCES FOR SNOW.
THE SAN LUIS VALLEY MAY MIX OUT SATURDAY...BUT WITH COLDER AIR
ALOFT TEMPERATURES WILL NOT INCREASE MUCH.
.TUESDAY...SURFACE HIGH PRESSURE WILL MOVE EAST OF THE REGION WITH
A REBOUND IN TEMPERATURE ANTICIPATED. WITH A SHORTWAVE RIDGE OVER
THE REGION...CHANCES FOR MOUNTAIN SNOW ARE SMALL. --PGW--
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1002 AM MST WED JAN 1 2014
MAIN CONCERN WILL BE LOW PROBABILITY OF SOME -SHRASN VC THE KPUB
AND KOCS TERMINALS TODAY. COULD SEE A BRIEF INCREASE IN SHOWER
COVERAGE IN THE 20-24Z TIME FRAME...BEFORE THINGS TAPER OFF TO
THE E INTO KS. WINDS FROM THE N-NW WILL GRADUALLY DIMINISH...BUT
THERE COULD BE AN OCCASIONAL GUSTY PERIOD OR TWO. IN THE SAN LUIS
VALLEY...THE PROBABILITY OF FG WILL AGAIN BE PRESENT BUT LOW DUE
TO THE AMOUNT OF DRY AIR ALOFT...SO WILL GO WITH THE ONGOING
FORECAST WHICH KEEPS KALS CLEAR TONIGHT. ROSE
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KT
LONG TERM...PGW
AVIATION...ROSE
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
439 PM EST WED JAN 1 2014
.SYNOPSIS...
A DEVELOPING LOW PRESSURE SYSTEM WILL BRING RAIN TO THE REGION
TONIGHT AND THURSDAY. A COLD FRONT WILL CROSS THE REGION THURSDAY
NIGHT WITH COLD DRY CANADIAN HIGH PRESSURE RETURNING FRIDAY AND
SATURDAY. THE NEXT SYSTEM IS EXPECTED TO BRING SHOWERS BACK INTO
THE REGION LATE SATURDAY NIGHT THROUGH EARLY MONDAY... FOLLOWED BY
COLD HIGH PRESSURE BUILDING IN THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
HIGH AND MID LEVEL CLOUDS WILL CONTINUE TO BLANKET THE AREA IN
SOUTHWEST FLOW ALOFT. CURRENT RADAR INDICATING PATCHES OF LIGHT
RAIN CROSSING THE CSRA AND SOUTHERN MIDLANDS.
HIGH PRESSURE CENTERED OFF THE MID-ATLANTIC COAST WAS RIDGING
INTO THE CAROLINAS AND GEORGIA. PWAT RANGING FROM LESS THAN HALF
AN INCH NORTH TO AROUND ONE INCH SOUTH IS FORECAST TO AROUND ONE
INCH NORTH TO 1.30 INCHES SOUTH TONIGHT. ALL MODELS INDICATE
ISENTROPIC LIFT INCREASING.
FORECAST MODELS CONTINUE THE CHANCE FOR RAIN IN THE SOUTHERN AND
EASTERN CWA THROUGH MIDNIGHT...THEN PUSH RAINFALL NORTH THE
REMAINDER OF THE NIGHT. HAVE CONTINUED WITH LIKELY/CATEGORICAL
POPS SOUTH/EAST...AND CHANCE POPS ACROSS THE EXTREME NORTH GIVEN
INCREASING ISENTROPIC LIFT. OVERNIGHT LOWS IN THE LOW/MID 40S ARE
CONSISTENT WITH MOS GUIDANCE.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
A FULL LATITUDE TROUGH WILL CROSS THE FORECAST AREA THURSDAY AND
THURSDAY NIGHT. ISENTROPIC LIFT WILL BE ONGOING THURSDAY MORNING
ACROSS THE SOUTHEASTERN HALF OF THE FORECAST AREA AND THIS WILL
SPREAD NORTHWESTWARD THROUGH THE MORNING INTO EARLY AFTERNOON
HOURS. PRECIPITABLE WATER VALUES WILL NOT BE AS HIGH AS THE PAST
COUPLE OF EVENTS BUT WILL SHOW A GRADIENT FROM AROUND AN INCH IN
THE NORTHWEST COUNTIES TO AROUND 1.3 INCHES IN THE SOUTHEASTERN
COUNTIES AND THE REGION WILL FALL WITHIN THE RIGHT ENTRANCE REGION
OF A 150 KT UPPER JET FURTHER SUPPORTING WIDESPREAD OMEGA OVER THE
REGION.
HAVE INCREASED POPS THURSDAY TO CATEGORICAL FOR ALL BUT THE WESTERN
MIDLANDS WHERE HIGH LIKELY POPS WILL BE HELD. LITTLE TO NO
INSTABILITY SO DO NOT EXPECT ANY THUNDER WITH THIS EVENT. QPF
AMOUNTS WILL BE LIMITED BY MODEST PRECIPITABLE WATER VALUES AND THE
SPEED OF THE SYSTEM. GENERALLY EXPECT AMOUNTS TO RANGE FROM A
QUARTER TO HALF INCH ACROSS THE WESTERN HALF OF THE FORECAST AREA
WITH A HALF TO THREE QUARTERS OF AN INCH POSSIBLE IN THE EAST.
THE TROUGH WILL BE QUICK TO MOVE THROUGH THE REGION AS SURFACE LOW
PRESSURE DEVELOPS OFF THE MID ATLANTIC COAST BY THURSDAY EVENING
DRAWING AN ARCTIC COLD FRONT ACROSS THE FORECAST AREA THURSDAY
EVENING. RAIN SHOULD COME TO AN END QUICKLY FROM WEST TO EAST
THURSDAY EVENING WHILE STRONG COLD ADVECTION TAKES PLACE THROUGH
FRIDAY IN THE WAKE OF THE FRONT...WITH 850MB TEMPERATURES FALLING INTO
THE -5C TO -10C RANGE FRIDAY. WINDS WILL BE STRONG THURSDAY NIGHT
INTO FRIDAY MORNING. RIGHT NOW HAVE SUSTAINED WINDS IN THE 15 TO
20 MPH RANGE WITH GUSTS UP TO 30 MPH. WILL HOLD OFF ON LAKE WIND
ADVISORY UNTIL MID SHIFT TONIGHT OR MORNING UPDATE THURSDAY.
TEMPERATURES ARE EXPECTED TO BE NEAR NORMAL IN THE 50S WITH
PRECIPITATION THURSDAY THEN FALL WELL BELOW NORMAL BY FRIDAY WITH
HIGHS STRUGGLING THROUGH THE LOWER TO MID 40S FRIDAY AND THEN A
COLD NIGHT FRIDAY NIGHT UNDER REASONABLE RADIATIONAL COOLING WITH
A VERY DRY AIR MASS IN PLACE WITH LOWS IN THE LOWER 20S.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
LATEST WPC GUIDANCE TRENDS TOWARD THE ECMWF WHICH IS MORE
AGGRESSIVE WITH RAIN CHANCES SAT NIGHT INTO SUNDAY NIGHT WITH THE
PASSAGE OF THE NEXT ARCTIC FRONT. EXISTING FORECAST WAS DRIER AND I
HAVE STARTED TRENDING TOWARD THE WPC GUIDANCE AS THE ECMWF HAS
GENERALLY PERFORMED BETTER FOR OUR AREA WITH PRECIP OVER THE PAST
WEEK OR TWO...ESPECIALLY IN THE LONGER TERM RANGES.
COLD HIGH PRESSURE BEGINS TO MOVE EAST OF THE AREA ON SATURDAY
BRINGING A RETURN FLOW WITH INCREASING MOISTURE. HIGHS WILL
CONTINUE BELOW NORMAL IN THE 40S. YET ANOTHER TROUGH WILL DIG
ACROSS THE MIDDLE PART OF THE COUNTRY SATURDAY NIGHT AND SUNDAY
INDUCING SURFACE LOW PRESSURE DEVELOPMENT OVER THE OHIO VALLEY ON
SUNDAY. ECMWF HAS DEEP POLAR VORTEX DROPPING INTO THE GREAT LAKES
REGION. AS SURFACE LOW MOVES NORTHEAST THE NEXT COLD/ARCTIC FRONT
WILL CROSS THE REGION.
WILL INCREASE POP INTO THE 40 TO 50 PERCENT RANGE SUNDAY. BEST
CHANCES FOR RAIN APPEARS TO BE SUNDAY NIGHT AND WILL RAISE POPS
INTO THE 50 TO 65 PERCENT RANGE. A VERY COLD ARCTIC AIR MASS WILL
BUILD OVER THE AREA BEHIND THE FRONT WITH STRONG COLD ADVECTION
MONDAY AND MONDAY NIGHT.
AHEAD OF THE FRONT SUNDAY...HIGH TEMPERATURES WILL MODERATE INTO
THE UPPER 50S AND LOWER 60S. THE COLD DRY AIR DOES NOT ARRIVE IN
EARNEST UNTIL MONDAY NIGHT WHEN TEMPERATURES WILL FALL INTO THE
MID 20S. HIGHS TUESDAY WILL STRUGGLE TO AROUND 40 DEGREES. WITH
HIGH PRESSURE OVER THE AREA TUESDAY NIGHT TEMPERATURES WILL FALL
TO AROUND 20 WITH HIGHS ON WEDNESDAY WARMING ONLY INTO THE LOWER
TO MID 40S.
&&
.AVIATION /22Z WEDNESDAY THROUGH MONDAY/...
LOW PRESSURE ALONG THE COAST WILL BRING INCREASING MOISTURE.
WIDESPREAD RAIN WITH LOWERING CEILINGS AND VISIBILITIES WILL OCCUR.
IFR CONDITIONS WILL DEVELOP. THE 17Z HRRR AND GFS LAMP SHOWED VFR OR
MVFR CONDITIONS TROUGH 06Z. THE GFS LAMP AND SREF GUIDANCE INDICATED
IFR CONDITIONS DEVELOPING 08Z TO 12Z.
EXTENDED AVIATION OUTLOOK...WIDESPREAD MVFR OR LOWER CONDITIONS
WILL LINGER INTO THURSDAY EVENING AS LOW PRESSURE DEEPENS OFF THE
NORTH CAROLINA AND VIRGINIA COAST. A STRONG COLD FRONT WILL CROSS
THE AREA THURSDAY NIGHT WITH CLEARING SKIES AND BREEZY CONDITIONS IN
ITS WAKE. ANOTHER STORM SYSTEM MAY BRING FLIGHT RESTRICTIONS
SATURDAY NIGHT AND SUNDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
433 PM EST WED JAN 1 2014
.SYNOPSIS...
A DEVELOPING LOW PRESSURE SYSTEM WILL BRING RAIN TO THE REGION
TONIGHT AND THURSDAY. A COLD FRONT WILL CROSS THE REGION THURSDAY
NIGHT WITH COLD DRY CANADIAN HIGH PRESSURE RETURNING FRIDAY AND
SATURDAY. THE NEXT SYSTEM IS EXPECTED TO BRING SHOWERS BACK INTO
THE REGION LATE SATURDAY NIGHT THROUGH EARLY MONDAY... FOLLOWED BY
COLD HIGH PRESSURE BUILDING IN THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
HIGH AND MID LEVEL CLOUDS WILL CONTINUE TO BLANKET THE AREA IN
SOUTHWEST FLOW ALOFT. CURRENT RADAR INDICATING PATCHES OF LIGHT
RAIN CROSSING THE CSRA AND SOUTHERN MIDLANDS.
HIGH PRESSURE CENTERED OFF THE MID-ATLANTIC COAST WAS RIDGING
INTO THE CAROLINAS AND GEORGIA. PWAT RANGING FROM LESS THAN HALF
AN INCH NORTH TO AROUND ONE INCH SOUTH IS FORECAST TO AROUND ONE
INCH NORTH TO 1.30 INCHES SOUTH TONIGHT. ALL MODELS INDICATE
ISENTROPIC LIFT INCREASING.
FORECAST MODELS CONTINUE THE CHANCE FOR RAIN IN THE SOUTHERN AND
EASTERN CWA THROUGH MIDNIGHT...THEN PUSH RAINFALL NORTH THE
REMAINDER OF THE NIGHT. HAVE CONTINUED WITH LIKELY/CATEGORICAL
POPS SOUTH/EAST...AND CHANCE POPS ACROSS THE EXTREME NORTH GIVEN
INCREASING ISENTROPIC LIFT. OVERNIGHT LOWS IN THE LOW/MID 40S ARE
CONSISTENT WITH MOS GUIDANCE.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
A FULL LATITUDE TROUGH WILL CROSS THE FORECAST AREA THURSDAY AND
THURSDAY NIGHT. ISENTROPIC LIFT WILL BE ONGOING THURSDAY MORNING
ACROSS THE SOUTHEASTERN HALF OF THE FORECAST AREA AND THIS WILL
SPREAD NORTHWESTWARD THROUGH THE MORNING INTO EARLY AFTERNOON
HOURS. PRECIPITABLE WATER VALUES WILL NOT BE AS HIGH AS THE PAST
COUPLE OF EVENTS BUT WILL SHOW A GRADIENT FROM AROUND AN INCH IN
THE NORTHWEST COUNTIES TO AROUND 1.3 INCHES IN THE SOUTHEASTERN
COUNTIES AND THE REGION WILL FALL WITHIN THE RIGHT ENTRANCE REGION
OF A 150 KT UPPER JET FURTHER SUPPORTING WIDESPREAD OMEGA OVER THE
REGION.
HAVE INCREASED POPS THURSDAY TO CATEGORICAL FOR ALL BUT THE WESTERN
MIDLANDS WHERE HIGH LIKELY POPS WILL BE HELD. LITTLE TO NO
INSTABILITY SO DO NOT EXPECT ANY THUNDER WITH THIS EVENT. QPF
AMOUNTS WILL BE LIMITED BY MODEST PRECIPITABLE WATER VALUES AND THE
SPEED OF THE SYSTEM. GENERALLY EXPECT AMOUNTS TO RANGE FROM A
QUARTER TO HALF INCH ACROSS THE WESTERN HALF OF THE FORECAST AREA
WITH A HALF TO THREE QUARTERS OF AN INCH POSSIBLE IN THE EAST.
THE TROUGH WILL BE QUICK TO MOVE THROUGH THE REGION AS SURFACE LOW
PRESSURE DEVELOPS OFF THE MID ATLANTIC COAST BY THURSDAY EVENING
DRAWING AN ARCTIC COLD FRONT ACROSS THE FORECAST AREA THURSDAY
EVENING. RAIN SHOULD COME TO AN END QUICKLY FROM WEST TO EAST
THURSDAY EVENING WHILE STRONG COLD ADVECTION TAKES PLACE THROUGH
FRIDAY IN THE WAKE OF THE FRONT...WITH 850MB TEMPERATURES FALLING INTO
THE -5C TO -10C RANGE FRIDAY. WINDS WILL BE STRONG THURSDAY NIGHT
INTO FRIDAY MORNING. RIGHT NOW HAVE SUSTAINED WINDS IN THE 15 TO
20 MPH RANGE WITH GUSTS UP TO 30 MPH. WILL HOLD OFF ON LAKE WIND
ADVISORY UNTIL MID SHIFT TONIGHT OR MORNING UPDATE THURSDAY.
TEMPERATURES ARE EXPECTED TO BE NEAR NORMAL IN THE 50S WITH
PRECIPITATION THURSDAY THEN FALL WELL BELOW NORMAL BY FRIDAY WITH
HIGHS STRUGGLING THROUGH THE LOWER TO MID 40S FRIDAY AND THEN A
COLD NIGHT FRIDAY NIGHT UNDER REASONABLE RADIATIONAL COOLING WITH
A VERY DRY AIR MASS IN PLACE WITH LOWS IN THE LOWER 20S.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
LATEST WPC GUIDANCE TRENDS TOWARD THE ECMWF WHICH IS MORE
AGGRESSIVE WITH RAIN CHANCES SAT NIGHT INTO SUNDAY NIGHT WITH THE
PASSAGE OF THE NEXT ARCTIC FRONT. EXISTING FORECAST WAS DRIER AND I
HAVE STARTED TRENDING TOWARD THE WPC GUIDANCE AS THE ECMWF HAS
GENERALLY PERFORMED BETTER FOR OUR AREA WITH PRECIP OVER THE PAST
WEEK OR TWO...ESPECIALLY IN THE LONGER TERM RANGES.
COLD HIGH PRESSURE BEGINS TO MOVE EAST OF THE AREA ON SATURDAY
BRINGING A RETURN FLOW WITH INCREASING MOISTURE. HIGHS WILL
CONTINUE BELOW NORMAL IN THE 40S. YET ANOTHER TROUGH WILL DIG
ACROSS THE MIDDLE PART OF THE COUNTRY SATURDAY NIGHT AND SUNDAY
INDUCING SURFACE LOW PRESSURE DEVELOPMENT OVER THE OHIO VALLEY ON
SUNDAY. ECMWF HAS DEEP POLAR VORTEX DROPPING INTO THE GREAT LAKES
REGION. AS SURFACE LOW MOVES NORTHEAST THE NEXT COLD/ARCTIC FRONT
WILL CROSS THE REGION.
WILL INCREASE POP INTO THE 40 TO 50 PERCENT RANGE SUNDAY. BEST
CHANCES FOR RAIN APPEARS TO BE SUNDAY NIGHT AND WILL RAISE POPS
INTO THE 50 TO 65 PERCENT RANGE. A VERY COLD ARCTIC AIR MASS WILL
BUILD OVER THE AREA BEHIND THE FRONT WITH STRONG COLD ADVECTION
MONDAY AND MONDAY NIGHT. HIGH PRESSURE WILL BUILD OVER THE AREA SUNDAY
AND SUNDAY NIGHT.
AHEAD OF THE FRONT SUNDAY...HIGH TEMPERATURES WILL MODERATE INTO
THE UPPER 50S AND LOWER 60S. THE COLD DRY AIR DOES NOT ARRIVE IN
EARNEST UNTIL MONDAY NIGHT WHEN TEMPERATURES WILL FALL INTO THE
MID 20S. HIGHS TUESDAY WILL STRUGGLE TO AROUND 40 DEGREES. WITH
HIGH PRESSURE OVER THE AREA TUESDAY NIGHT TEMPERATURES WILL FALL
TO AROUND 20 WITH HIGHS ON WEDNESDAY WARMING ONLY INTO THE LOWER
TO MID 40S.
&&
.AVIATION /22Z WEDNESDAY THROUGH MONDAY/...
LOW PRESSURE ALONG THE COAST WILL BRING INCREASING MOISTURE.
WIDESPREAD RAIN WITH LOWERING CEILINGS AND VISIBILITIES WILL OCCUR.
IFR CONDITIONS WILL DEVELOP. THE 17Z HRRR AND GFS LAMP SHOWED VFR OR
MVFR CONDITIONS TROUGH 06Z. THE GFS LAMP AND SREF GUIDANCE INDICATED
IFR CONDITIONS DEVELOPING 08Z TO 12Z.
EXTENDED AVIATION OUTLOOK...WIDESPREAD MVFR OR LOWER CONDITIONS
WILL LINGER INTO THURSDAY EVENING AS LOW PRESSURE DEEPENS OFF THE
NORTH CAROLINA AND VIRGINIA COAST. A STRONG COLD FRONT WILL CROSS
THE AREA THURSDAY NIGHT WITH CLEARING SKIES AND BREEZY CONDITIONS IN
ITS WAKE. ANOTHER STORM SYSTEM MAY BRING FLIGHT RESTRICTIONS
SATURDAY NIGHT AND SUNDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
417 PM EST WED JAN 1 2014
.SYNOPSIS...
A DEVELOPING LOW PRESSURE SYSTEM WILL BRING RAIN TO THE REGION
TONIGHT AND THURSDAY. A COLD FRONT WILL CROSS THE REGION THURSDAY
NIGHT WITH COLD DRY CANADIAN HIGH PRESSURE RETURNING FRIDAY AND
SATURDAY. THE NEXT SYSTEM IS EXPECTED TO BRING SHOWERS BACK INTO
THE REGION LATE SATURDAY NIGHT THROUGH EARLY MONDAY... FOLLOWED BY
COLD HIGH PRESSURE BUILDING IN THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
HIGH AND MID LEVEL CLOUDS WILL CONTINUE TO BLANKET THE AREA THIS
AFTERNOON IN SOUTHWEST FLOW ALOFT. CURRENT RADAR INDICATING
PATCHES OF LIGHT RAIN CROSSING THE CSRA AND SOUTHERN MIDLANDS.
HIGH PRESSURE CENTERED OFF THE MID-ATLANTIC COAST WAS RIDGING
INTO THE CAROLINAS AND GEORGIA. PWAT RANGING FROM LESS THAN HALF
AN INCH NORTH TO AROUND ONE INCH SOUTH IS FORECAST TO AROUND ONE
INCH NORTH TO 1.30 INCHES SOUTH TONIGHT. ALL MODELS INDICATE
ISENTROPIC LIFT INCREASING.
AREAS NORTH OF MCCORMICK...COLUMBIA AND SUMTER WILL REMAIN DRY
FOR REST OF THE AFTERNOON. KEPT LOW CHANCE FOR LIGHT RAIN ACROSS
THE SOUTH. SHAVED A DEGREE OR TWO FROM AFTERNOON TEMPERATURES FOR
HIGHS IN THE LOW TO MID 50S.
FORECAST MODELS CONTINUE THE CHANCE FOR RAIN IN THE SOUTHERN AND
EASTERN CWA THROUGH MIDNIGHT...THEN PUSH RAINFALL NORTH THE
REMAINDER OF THE NIGHT. HAVE CONTINUED WITH LIKELY/CATEGORICAL
POPS SOUTH/EAST...AND CHANCE POPS ACROSS THE EXTREME NORTH GIVEN
INCREASING ISENTROPIC LIFT. OVERNIGHT LOWS IN THE LOW/MID 40S ARE
CONSISTENT WITH MOS GUIDANCE.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY NIGHT/...
A FULL LATITUDE TROUGH WILL CROSS THE FORECAST AREA THURSDAY AND
THURSDAY NIGHT. ISENTROPIC LIFT WILL BE ONGOING THURSDAY MORNING
ACROSS THE SOUTHEASTERN HALF OF THE FORECAST AREA AND THIS WILL
SPREAD NORTHWESTWARD THROUGH THE MORNING INTO EARLY AFTERNOON
HOURS. PRECIPITABLE WATER VALUES WILL NOT BE AS HIGH AS THE PAST
COUPLE OF EVENTS BUT WILL SHOW A GRADIENT FROM AROUND AN INCH IN
THE NORTHWEST COUNTIES TO AROUND 1.3 INCHES IN THE SOUTHEASTERN
COUNTIES AND THE REGION WILL FALL WITHIN THE RIGHT ENTRANCE REGION
OF A 150 KT UPPER JET FURTHER SUPPORTING WIDESPREAD OMEGA OVER THE
REGION.
HAVE INCREASED POPS THURSDAY TO CATEGORICAL FOR ALL BUT THE WESTERN
MIDLANDS WHERE HIGH LIKELY POPS WILL BE HELD. LITTLE TO NO
INSTABILITY SO DO NOT EXPECT ANY THUNDER WITH THIS EVENT. QPF
AMOUNTS WILL BE LIMITED BY MODEST PRECIPITABLE WATER VALUES AND THE
SPEED OF THE SYSTEM. GENERALLY EXPECT AMOUNTS TO RANGE FROM A
QUARTER TO HALF INCH ACROSS THE WESTERN HALF OF THE FORECAST AREA
WITH A HALF TO THREE QUARTERS OF AN INCH POSSIBLE IN THE EAST.
THE TROUGH WILL BE QUICK TO MOVE THROUGH THE REGION AS SURFACE LOW
PRESSURE DEVELOPS OFF THE MID ATLANTIC COAST BY THURSDAY EVENING
DRAWING AN ARCTIC COLD FRONT ACROSS THE FORECAST AREA THURSDAY
EVENING. RAIN SHOULD COME TO AN END QUICKLY FROM WEST TO EAST
THURSDAY EVENING WHILE STRONG COLD ADVECTION TAKES PLACE THROUGH
FRIDAY IN THE WAKE OF THE FRONT...WITH 850MB TEMPERATURES FALLING INTO
THE -5C TO -10C RANGE ON FRIDAY. WINDS WILL BE STRONG THURSDAY
NIGHT INTO FRIDAY MORNING. RIGHT NOW HAVE SUSTAINED WINDS IN THE
15 TO 20 MPH RANGE WITH GUSTS UP TO 30 MPH. WILL HOLD OFF ON LAKE
WIND ADVISORY UNTIL MID SHIFT TONIGHT OR MORNING UPDATE ON THURSDAY.
TEMPERATURES ARE EXPECTED TO BE
NEAR NORMAL IN THE 50S WITH PRECIPITATION ON THURSDAY THEN FALL
WELL BELOW NORMAL BY FRIDAY WITH HIGHS STRUGGLING THROUGH THE
LOWER TO MID 40S ON FRIDAY AND THEN A COLD NIGHT FRIDAY NIGHT
UNDER REASONABLE RADIATIONAL COOLING WITH A VERY DRY AIR MASS IN
PLACE WITH LOWS IN THE LOWER 20S.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
LATEST WPC GUIDANCE TRENDS TOWARD THE ECMWF WHICH IS MORE
AGGRESSIVE WITH RAIN CHANCES SAT NIGHT INTO SUNDAY NIGHT WITH THE
PASSAGE OF THE NEXT ARCTIC FRONT. EXISTING FORECAST WAS DRIER AND I
HAVE STARTED TRENDING TOWARD THE WPC GUIDANCE AS THE ECMWF HAS
GENERALLY PERFORMED BETTER FOR OUR AREA WITH PRECIP OVER THE PAST
WEEK OR TWO...ESPECIALLY IN THE LONGER TERM RANGES.
COLD HIGH PRESSURE BEGINS TO MOVE EAST OF THE AREA ON SATURDAY
BRINGING A RETURN FLOW WITH INCREASING MOISTURE. HIGHS WILL
CONTINUE BELOW NORMAL IN THE 40S. YET ANOTHER TROUGH WILL DIG
ACROSS THE MIDDLE PART OF THE COUNTRY SATURDAY NIGHT AND SUNDAY
INDUCING SURFACE LOW PRESSURE DEVELOPMENT OVER THE OHIO VALLEY ON
SUNDAY. ECMWF HAS DEEP POLAR VORTEX DROPPING INTO THE GREAT LAKES
REGION. AS SURFACE LOW MOVES NORTHEAST THE NEXT COLD/ARCTIC FRONT
WILL CROSS THE REGION.
WILL INCREASE POP INTO THE 40 TO 50 PERCENT RANGE ON SUNDAY. BEST
CHANCES FOR RAIN APPEARS TO BE SUNDAY NIGHT AND WILL RAISE POPS
INTO THE 50 TO 65 PERCENT RANGE. A VERY COLD ARCTIC AIR MASS WILL
BUILD OVER THE AREA BEHIND THE FRONT WITH STRONG COLD ADVECTION
MONDAY AND MONDAY NIGHT. HIGH PRESSURE WILL BUILD OVER THE AREA ON
SUNDAY AND SUNDAY NIGHT.
AHEAD OF THE FRONT ON SUNDAY...HIGH TEMPERATURES WILL MODERATE
INTO THE UPPER 50S AND LOWER 60S. THE COLD DRY AIR DOES NOT ARRIVE
IN EARNEST UNTIL MONDAY NIGHT WHEN TEMPERATURES WILL FALL INTO THE
MID 20S. HIGHS TUESDAY WILL STRUGGLE TO AROUND 40 DEGREES. WITH
HIGH PRESSURE OVER THE AREA TUESDAY NIGHT TEMPERATURES WILL FALL
TO AROUND 20 WITH HIGHS ON WEDNESDAY WARMING ONLY INTO THE LOWER
TO MID 40S.
&&
.AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
LOW PRESSURE ALONG THE COAST WILL BRING INCREASING MOISTURE.
WIDESPREAD RAIN WITH LOWERING CEILINGS AND VISIBILITIES WILL OCCUR.
IFR CONDITIONS WILL DEVELOP. THE 17Z HRRR AND GFS LAMP SHOWED VFR OR
MVFR CONDITIONS TROUGH 06Z. THE GFS LAMP AND SREF GUIDANCE INDICATED
IFR CONDITIONS DEVELOPING 08Z TO 12Z.
EXTENDED AVIATION OUTLOOK...WIDESPREAD MVFR OR LOWER CONDITIONS
WILL LINGER INTO THURSDAY EVENING AS LOW PRESSURE DEEPENS OFF THE
NORTH CAROLINA AND VIRGINIA COAST. A STRONG COLD FRONT WILL CROSS
THE AREA THURSDAY NIGHT WITH CLEARING SKIES AND BREEZY CONDITIONS IN
ITS WAKE. ANOTHER STORM SYSTEM MAY BRING FLIGHT RESTRICTIONS
SATURDAY NIGHT AND SUNDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS DODGE CITY KS
1109 AM CST Wed Jan 1 2014
...Updated for Aviation...
.SYNOPSIS...
ISSUED AT 339 AM CST WED JAN 1 2014
Water vapor loop during the overnight hours showed a digging
shortwave trough across eastern Wyoming...reaching northern Colorado
as of 09Z. This shortwave trough encompassed a much larger scale
gyre that was centered over southeastern Hudson Bay. In the lower
troposphere, temperatures were fairly mild on the High Plains with
850mb temperatures from +8 to +10C. Meanwhile, the very sharp
baroclinic zone at 850mb was found from northeastern Montana through
northeastern Nebraska per 00Z RAOB and RAP analysis. Surface
temperatures across Nebraska on the 09Z analysis ranged from 35F at
Scottsbluff to +8F at O`Neill on the other side of the front. Below
zero temperatures (degF) were not too far away into southeastern
South Dakota.
&&
.UPDATE...
ISSUED AT 504 AM CST WED JAN 1 2014
There seems to be enough of a signal in the most recent mesoscale
model solutions to bump up snowfall amounts in the northeast
counties (northeast of a Scott City to Jetmore to Pratt line). A
look at the 03Z run of the SREF Plumes for Hays indicates a mean
of all perturbations just under 2 inches. However, much of that is
influenced by the seemingly wet WRF-ARW core. The WRF-ARW
perturbations are clustered between 3 and 4 inches at Hays. While
we do not necessarily believe total snowfall will be quite that
high given the fast speed of the system, some brief moderate-high
snowfall rates as the 700mb zone of frontogenesis passes would
argue for at least an inch or two of final snowfall. As a result,
we have bumped up the snowfall just a bit to around an inch and a
half along I-70... and the half inch line down to roughly Scott
City-Jetmore-Pratt line. With the increased snowfall forecast, we
will have to think more about the blowing and drifting potential
as 18 to 22 knot sustained winds will add to reduced visibility
for a few hours this afternoon. We will hold off on issuing a
winter weather advisory with sub-two inch forecast amounts, but it
is something that the incoming day shift will need to monitor
closely.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 339 AM CST WED JAN 1 2014
As mentioned in the synopsis section, a sharp baroclinic zone was
found across Nebraska. As the mid-level shortwave trough moves
southeast into western Kansas today, some of this arctic air
residing in central Nebraska will advect southward on
northeast...and eventually due north winds. The problem in the
forecast for today is just how far southwest this arctic airmass
will reach. North-northwest winds at the surface near the Colorado
border will not be advecting in much of that arctic air at all (It
was still 31F in Douglas, WY and 35F in Scottsbluff, NE as of
09Z!). We foresee a fairly sharp temperature gradient across
western Kansas today. There is a rather high degree of uncertainty
in the temperature forecast west of Highway 283. The official
forecast will call for steady or falling temperatures through the
day northeast of roughly Dighton to Dodge City to Pratt. Northeast
of this line, there is a fairly high degree of confidence in the
temperature forecast...and that it will be very cold with
temperatures falling through the 20s...and into the mid to upper
teens potentially at Hays. Then there is the
Elkhart-Johnson-Syracuse corridor. This area, if they see any of
this arctic air at all, will be later in the day. This will allow
the Colorado border areas to warm well into the upper 30s to lower
40s. By early to mid afternoon, we could very well see a 30-degree
temperature gradient from southwest to northeast across the DDC
forecast area (from Elkhart to Hays).
Now on to the snow. Nothing much has really changed from previous
forecast thinking. The shortwave trough will be zipping southeast
quickly today, and there will only be a 2 to 4 hour period of light
to briefly moderate snow across the far northeastern zones (most
particularly, Hays-Victoria)...along the zone of strongest 700mb
frontogenesis. The best of this frontogenetic response at 700mb will
be just northeast of the DDC forecast area (across north-central
Kansas) as is indicated by the latest NAM12 and WRF runs. There
could be a brief period of some showery type snow along the Scott
City to Dodge City to Pratt corridor from midday to late afternoon
as a pocket of very slight potential instability develops in the mid
levels right near the 400-500mb potential vorticity anomaly. This
could put down a quickly quarter to half inch of snow in some
scattered spots along the Scott City-Dodge City-Pratt axis.
All of the snow and/or snow showers will be well east of the
southwest Kansas region by early this evening. Downslope
trajectories will resume overnight with a light westerly surface
wind developing especially along/west of Highway 83. Temperatures
should stabilize in the upper teens to lower 20s if not very slowly
rise toward 12Z. Across central Kansas, temperatures will likely
bottom out around +10F.
.LONG TERM...(Thursday through Tuesday)
ISSUED AT 348 AM CST WED JAN 1 2014
A warming trend will commence Thursday and Friday as the mid to
upper level flow becomes more zonal across the Rockies, and surface
pressures fall in the lee of the Rockies. Highs should make it
into the 40s in most places Thursday as the arctic air gets shunted
into eastern Kansas given the increasing low to mid level westerly
momentum. A progressive, positively tilted shortwave trough will
approach from the northwest by Saturday, and as one would expect with
a positively tilted system, a cold surge will pass through western
Kansas ahead of the feature. In spite of the cold advection, some
light snow is possible as the trough approaches, with only minor
accumulations of an inch or less expected. Then by Sunday, a lobe of
the polar vortex will rotate southeastward into the northern plains
and upper Midwest. This will provide a glancing blow of arctic air
into Kansas for Sunday night into Monday, with moderating
temperatures by Tuesday and Wednesday into the 30s for highs as the
low level flow quickly becomes more westerly. The next upper
trough will approach Kansas by Wednesday and Thursday, but a lack
of deep moisture may preclude precipitation. However, if this
system is slower and more amplified, then some rain or snow would
be possible.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
ISSUED AT 1101 AM CST WED JAN 1 2014
A mesoscale band of moderate snow associated with an upper level
shortwave trough will quickly move across southwest and south
central Kansas this afternoon, then end before 21-23Z. Cigs may
drop to IFR conditions especially in the KHYS area where around 2
inches of snow is forecast. Winds of 20-30kt with the snow band
may have some reduced visibilities. Cigs improve rapidly behind
the snow band with MVFR to VFR conditions overnight and winds
decreasing.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 27 16 44 21 / 60 10 0 0
GCK 31 18 45 20 / 30 10 0 0
EHA 46 21 49 26 / 30 10 0 0
LBL 39 21 47 26 / 40 10 0 0
HYS 20 11 36 17 / 100 10 0 0
P28 34 17 39 19 / 40 40 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Umscheid
SYNOPSIS...Umscheid
SHORT TERM...Umscheid
LONG TERM...Finch
AVIATION...Kruse
AREA FORECAST DISCUSSION
NWS BISMARCK ND
130 PM CST WED JAN 1 2014
.UPDATE...
ISSUED AT 130 PM CST WED JAN 1 2014
NO SIGNIFICANT CHANGES WITH THIS UPDATE OTHER THAN TO ADJUST FOR
THE 18-1930 UTC SKY TRENDS WITH MOSTLY SUNNY CONDITIONS IN PLACE
AND EXPECTED TO REMAIN THROUGH THE AFTERNOON ACROSS THE NORTH
CENTRAL. THIS IS CLOSE THE 18 UTC RAP SKY COVER FORECAST INTO THE
EARLY EVENING...WITH DECREASING CLOUDS FROM NORTHEAST TO SOUTHWEST.
UPDATE ISSUED AT 1000 AM CST WED JAN 1 2014
ALLOWED THE WIND CHILL ADVISORY TO EXPIRE WITH THIS UPDATE...AS
WIND CHILLS WILL CONTINUE TO SLOWLY IMPROVE THROUGH THE LATE
MORNING AND AFTERNOON. HOWEVER...ANOTHER WIND CHILL ADVISORY MAY
BE NEEDED ACROSS THE NORTH AND CENTRAL TONIGHT. OTHERWISE...ADDED
A MENTION OF FLURRIES INTO THE AFTERNOON UNDER THE STRATUS.
UPDATE ISSUED AT 643 AM CST WED JAN 1 2014
UPDATED TO INCREASE PRECIPITATION CHANCES OVER THE NEXT FEW HOURS
AS THE BANDED SNOW TRANSLATES SOUTHEASTWARD THIS MORNING. KMOT
DROPPED TO 1 SM WITH SNOW EARLIER THIS MORNING...AND LARGE FLAKES
HAVE BEEN FALLING FOR SOME TIME IN BISMARCK. COVERAGE WAS
DETERMINED USING A COMBINATION OF SATELLITE...RADAR...AND SURFACE
OBSERVATIONS.
THE WIND CHILL ADVISORY STILL LOOKS GOOD...SO NO CHANGES THERE.
UPDATE
ISSUED AT 500 AM CST WED JAN 1 2014
QUICK UPDATE TO INCREASE POPS EARLY THIS MORNING. LATEST RAP AND
RADAR IMAGERY SUPPORT LIKELY TO CATEGORICAL POPS NORTHWEST AND
CENTRAL...EAST OF THE SFC TROUGH OVER MY WEST. NO OTHER CHANGES
WITH THIS UPDATE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CST WED JAN 1 2014
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE COLD
TEMPERATURES AND WIND CHILLS THROUGH THE PERIOD...ALONG WITH
LINGERING LIGHT SNOW THIS MORNING.
CURRENTLY...UPPER LEVEL RIDGE ACROSS THE WEST COAST EXTENDS NORTH
INTO ALASKA...WITH A DEEP UPPER LEVEL LOW OVER SOUTHEAST CANADA.
THIS RESULTS IN NORTHWEST FLOW ALOFT OVER THE NORTHERN
PLAINS...WITH MID LEVEL EMBEDDED ENERGY TRACKING SOUTHEAST ACROSS
THE LOCAL AREA. MID LEVEL IMPULSES COMBINED WITH CONTINUED
ISENTROPIC LIFT EAST OF A SFC TROUGH CURRENTLY POSITIONED OVER THE
FAR WESTERN DAKOTAS...MAINTAINS EXTENSIVE CLOUDINESS ACROSS WEST
AND CENTRAL NORTH DAKOTA...ALONG WITH AREAS OF LIGHT SNOW EAST OF
THE TROUGH AXIS. WHILE CLOUDS REMAIN THROUGH THE MORNING...CHANCES
FOR LIGHT SNOW ARE EXPECTED TO DIMINISH FROM WEST TO EAST NOW
THROUGH 18Z AS ENERGY ALOFT MOVES OUT OF THE REGION AND AS THE SFC
TROUGH MOVES SOUTH AND EAST DECREASING THE OVERRUNNING FLOW WITH
WINDS TRANSITIONING TO MORE OF A NORTHERLY COMPONENT.
BROAD HIGH PRESSURE DEVELOPS SOUTHWARD INTO THE REGION TODAY...AND
MAY RESULT IN PARTIAL CLEARING ACROSS THE NORTH. CLOUDS ARE FORECAST
TO LINGER SOUTH AND WESTWARD. CURRENT TEMPERATURES FROM 10 ABOVE
SOUTHWEST...SINGLE DIGITS BELOW CENTRAL...AND 10-15 BELOW EAST ARE
NOT EXPECTED TO RECOVER MUCH TODAY...WARMING BY ONLY 5 DEGREES OR
SO WITH THE COLD AIRMASS REMAINING OVER THE STATE.
CHANCES FOR LIGHT SNOW WILL REMAIN IN THE FORECAST WEST THIS
AFTERNOON INTO TONIGHT AS ANOTHER SFC TROUGH/FRONTAL BOUNDARY
DEVELOPS FROM NORTH CENTRAL MONTANA SOUTHEAST INTO WESTERN
NEBRASKA. THIS POSITION IS VERY SIMILAR TO THE PAST COUPLE OF
DAYS WHERE WE SAW ACCUMULATING LIGHT SNOW WEST INTO SOUTH
CENTRAL...WITH THE MAIN DIFFERENCE THIS TIME THE PLACEMENT OF
STRONG HIGH PRESSURE ACROSS EASTERN NORTH DAKOTA. THUS I EXPECT
THE SNOW TO BE CONFINED TO FAR WESTERN ND WITH STRONG SUBSIDENCE
IN CONTROL OVER THE EASTERN TWO THIRDS OF THE STATE. CLEAR TO
PARTLY CLOUDY SKIES ACROSS MY EASTERN ONE HALF TONIGHT COUPLED
WITH LIGHT WINDS WILL LEAD TO A VERY COLD NIGHT...WITH MORNING
LOWS ON THURSDAY 20-25 BELOW NORTHWEST...CENTRAL...AND EAST.
BALMY SOUTHWEST WHERE A LOW OF ZERO IS CURRENTLY FORECAST. WIND
CHILL HEADLINES WILL BE QUESTIONABLE AS WINDS MAY BE CALM WHERE
THE COLDEST TEMPERATURES ARE EXPECTED.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 350 AM CST WED JAN 1 2014
THE MAIN FOCUS OF TODAY`S FORECAST IS ON THE FRIDAY CLIPPER SYSTEM
AND ASSOCIATED FRIGID AIR MOVING INTO THE REGION ON SATURDAY.
MODELS/ENSEMBLES AGREE ON A GRADUAL WARMING TREND THROUGH
FRIDAY...WHEN PRE-CLIPPER WARM AIR ADVECTION DRIVES HIGHS INTO THE
LOW TO MID 30S. ASSOCIATED PRECIPITATION WILL LIKELY BE RAIN OR
SNOW. 00 UTC NAM/GFS/SREF BUFKIT SOUNDINGS ACROSS THE WEST SUPPORT
ONLY MINIMAL MELTING ALOFT...SINCE THE MAJORITY OF PRECIPITATION
FALLS AFTER THE COLD FRONTAL PASSAGE. LIQUID PRECIPITATION OF UP TO
0.1 INCH MEANS THAT EVEN IF IT IS ALL SNOW...ACCUMULATIONS WILL BE
MINIMAL.
THE ARCTIC AIR MASS FOLLOWING THIS CLIPPER WILL DROP LOW
TEMPERATURES DOWN TO AROUND -20F ON SUNDAY AND MONDAY NIGHTS. THIS
COLD WILL BE ACCOMPANIED BY WIND...SO RESULTING WIND CHILLS WILL BE
-40F TO -50F. IT IS WORTH NOTING THAT THE 00 UTC ECMWF SUPPORTS EVEN
COLDER AIR MOVING INTO THE REGION. A RETURN TO NEAR NORMAL
TEMPERATURES IS FORECAST BY THE MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 130 PM CST WED JAN 1 2014
SCATTERED MVFR CONDITIONS IN LIGHT SNOW AND STRATUS WILL CONTINUE
ACROSS MUCH OF WESTERN AND SOUTH CENTRAL NORTH DAKOTA INTO THE
AFTERNOON. EXPECT VFR CONDITIONS DEVELOPING TONIGHT INTO THURSDAY
MORNING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...NH
LONG TERM...SCHECK
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
305 PM CST WED JAN 1 2014
.SHORT TERM (TONIGHT THROUGH THURSDAY NIGHT)...
THIS AFTERNOON A PERSISTENT STRATOCU DECK WAS LOCATED EAST OF A LINE
FROM CARRIZO SPRINGS TO FREDERICKSBURG TO GEORGETOWN. THIS CLOUD DECK
WILL SLOWLY ERODE FROM WEST TO EAST THIS EVENING IN ADVANCE OF THE
COLD FRONT. AT 21Z THE COLD FRONT WAS LOCATED OVER THE TEXAS SOUTH
PLAINS MOVING SOUTHWARD. THE FRONT WILL ENTER THE HILL COUNTRY
BETWEEN 10 AND 11 PM THIS EVENING BASED ON THE LATEST RUC13 MODEL
SOLUTION. THIS WILL BE A DRY FROPA...HOWEVER A BRIEF PERIOD OF
PRE-FRONTAL PATCHY FOG IS POSSIBLE SOUTH AND EAST OF THE I-35
CORRIDOR WITH MORE WIDESPREAD FOG POSSIBLE ACROSS DIMMIT AND
SOUTHERN MAVERICK COUNTIES. POST-FRONTAL WINDS TONIGHT WILL BE
NORTHERLY AT 10 TO 20 MPH WITH GUSTS OF 30 MPH. LOWS THURSDAY
MORNING WILL RANGE FROM AROUND 30 ACROSS THE HILL COUNTRY TO NEAR
40 SOUTHWEST. THURSDAY WILL BE SUNNY AND COOLER AS CAA CONTINUES
THROUGHOUT THE DAY. HIGHS THURSDAY WILL BE 8 TO 12 DEGREES BELOW
NORMAL. GUSTY NORTHERLY WINDS WILL DIMINISH BY EVENING WITH THE
WEAKENING PRESSURE GRADIENT. GOOD RADIATIONAL COOLING WILL OCCUR
THURSDAY NIGHT INTO FRIDAY MORNING. THIS WILL RESULT IN A HARD
FREEZE FOR MUCH OF SOUTH CENTRAL TEXAS. THE LOW TEMP FCST FOR
THURSDAY NIGHT WILL BE A BLEND OF THE MET/MAV/ECMWF MOS GUIDANCE.
&&
.LONG TERM (FRIDAY THROUGH WEDNESDAY)...
BELOW NORMAL TEMPERATURES WILL CONTINUE NEXT WEEK DUE TO A SERIES
OF FROPAS. HOWEVER A BRIEF WARMING TREND WILL OCCUR FRIDAY AND
SATURDAY. HIGHS ON SATURDAY WILL BE IN LOWER 60S ACROSS THE HILL
COUNTRY WITH MID 60S ACROSS THE REMAINDER OF SOUTH CENTRAL TEXAS.
THE NEXT COLD FRONT WILL MOVE ACROSS THE REGION ON SUNDAY. ONCE
AGAIN AFTERNOON HIGHS WILL BE 5 TO 8 DEGREES BELOW NORMAL...RANGING
FROM THE UPPER 40S HILL COUNTRY TO NEAR 60 SOUTHWEST. LOW LEVEL
MOISTURE WILL BE LIMITED...WITH ONLY A SLIGHT CHANCE OF SHOWERS
FOR OUR EXTREME EASTERN COUNTIES. A RE-ENFORCEMENT OF THE COLD
AIRMASS WILL OCCUR ON TUESDAY WITH THE PASSAGE OF ANOTHER COLD
FRONT. WAA/OVERRUNNING/ISENTROPIC LIFT ON WEDNESDAY WILL LEAD TO
A SLIGHT CHANCE OF SHOWERS FOR MUCH OF THE REGION.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 36 52 29 53 40 / 0 0 0 0 0
AUSTIN BERGSTROM INTL AIRPORT 33 51 24 52 35 / - 0 0 0 0
NEW BRAUNFELS MUNI AIRPORT 35 54 26 54 37 / 0 0 0 0 0
BURNET MUNI AIRPORT 31 49 24 52 37 / 0 0 0 0 0
DEL RIO INTL AIRPORT 36 55 30 55 38 / 0 0 0 0 0
GEORGETOWN MUNI AIRPORT 31 50 24 52 39 / 0 0 0 0 0
HONDO MUNI AIRPORT 37 57 25 55 38 / 0 0 0 0 0
SAN MARCOS MUNI AIRPORT 35 52 26 54 37 / 0 0 0 0 0
LA GRANGE - FAYETTE REGIONAL 36 51 28 53 41 / 10 0 0 0 0
SAN ANTONIO INTL AIRPORT 37 56 28 55 40 / 0 0 0 0 0
STINSON MUNI AIRPORT 39 57 29 56 41 / 0 0 0 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...09
SYNOPTIC/GRIDS...13
PUBLIC SERVICE/DATA COLLECTION...12
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1210 PM CST WED JAN 1 2014
.UPDATE...UPGRADED MILWAUKEE AND RACINE TO WARNING BASED ON
RECENT SNOWS COMBINED WITH ONGOING TRENDS AND DECENT BAND MOVING
ONSHORE. ON TOP OF THIS...THE LAKE EFFECT SETUP CONTINUES TO
BECOME MORE FAVORABLE WITH TIME AS THE PROGGD EQL/LAKE INDUCED
CAPE CONTINUES TO RISE. DELTA T RISES TO 20C TONIGHT. SO MAY BE
ADDING MORE INCHES TO THE GOING FORECAST AMOUNTS BASED ON WHERE
THE PRIMARY BAND INTERSECTS LAND AREAS. MESO MODELS INCLUDING
HRRR/ARW/SPC WRF ARE EITHER NOT TOO EXCITED OR SHOW A NEAR-MISS
WITH PRIMARY BAND. HOWEVER NAM AND RAP SOUNDINGS PAINT QUITE A BIT
OF CONCERN WITH FAVORABLE FETCH AND INCREASING INSTABILITY WITH
TIME. NAM AND GFS ALSO SHOW THE QPF AFFECTING AT LEAST THE
LAKESHORE COUNTIES IN THE QPF PANELS THROUGH AT LEAST MIDDAY
THURSDAY. DECENT CORRIDOR OF 925-850 MILLIBAR CONVERGENCE DURING
THIS PERIOD...ESPECIALLY ON THE GFS. TRAJECTORIES GRADUALLY
BECOME LESS FAVORABLE AFTER 18Z THURSDAY.
PC
&&
.AVIATION/18Z TAFS/...MAIN CONCERN IS LAKE EFFECT SNOWS PERSISTING
THIS PERIOD FOR THE EASTERN TAFS INCLUDING KUES. KMSN WILL SEE
LITTLE IF ANY SNOW THIS PERIOD. MVFR CIGS WIDESPREAD ASSOCIATED
WITH THE LAKE EFFECT WITH IFR VSBYS IN THE HEAVIER BANDS. KUES
WILL GRADUALLY SHIFT OUT OF THE POTENTIAL AS WINDS BECOME MORE
SHORE PARALLEL LATER TNGT INTO THU. MEANWHILE POTENTIAL CONTINUES
FOR KMKE AND KENW INTO THE EARLY AFTERNOON HOURS.
PC
&&
.PREV DISCUSSION... /ISSUED 355 AM CST WED JAN 1 2014/
TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
PRESSURE GRADIENT AND SHIFTING WINDS CAUSING SOME SLIGHT INCREASE
IN WIND SPEEDS ACROSS NORTHERN CWA WHERE TEMPERATURES HAVE FALLEN
TO AROUND -3. WIND CHILLS WL CONTINUE TO HOVER AROUND -20 THROUGH
THE EARLY MORNING ACROSS THE NORTHERN TIER SO WL POST WIND CHILL
ADVISORY.
FAR SOUTHERN WI WILL GET CLIPPED BY LAYER Q-VECTOR CONVERGENCE
AND RIGHT ENTRANCE REGION OF UPPER JET FOR A TIME THIS MORNING
BEFORE SHIFTING OFF TO THE EAST. HENCE EXPECT A PERIOD OF -SN THIS
MORNING WITH UP TO ONE INCH ADDITIONAL ACCUMULATION. -SN SHOULD
BEGIN TO TAPER LATE MRNG THRU MID-AFTN.
PRIMARY FOCUS IS ON LAKE EFFECT SNOW SHOWERS. 1000-850MB WINDS IN
THE PROCESS OF TURNING ONSHORE IN RESPONSE TO DEVELOPING LOW
PRESSURE SAGGING INTO THE SOUTHERN PLAINS. MAIN SYSTEM SNOW WITH
THIS LOW EXPECTED TO REMAIN JUST SOUTH OF WI TODAY AND TONIGHT AS
LOW MOVES EAST ACROSS THE SOUTHERN PLAINS AND HEADS TOWARD THE TN
VALLEY AND UNDERGOES CYCLOGENESIS TNGT INTO THU.
THIS SCENARIO WILL RESULT IN A PROLONGED PERIOD OF ONSHORE WINDS
TODAY THRU THU. AVERAGING LAKE MI TEMP AROUND 36...RESULTS IN
DELTA T VALUES OF 15 TO 18 DEGREES CELSIUS TODAY...INCREASING TO
20 DEGREES CELSIUS TNGT INTO THU. FOR THE BULK OF THE
TIME...ENHANCED SYNTOPTIC SCALE LIFT REMAINS SOUTH OF THE AREA.
DEEP MOISTURE IN DENDRITIC GROWTH ZONE HOWEVER PERIODS OF DRYING
NOTED ABOVE 3500FT INVERSION TODAY AND TONIGHT. INCREASING
CONVERGENCE AND DELTA T VALUES WILL RESULT IN OCNL SHSN IN
EASTERN CWA DEVELOPING THIS MRNG. BEST THREAT FOR HEAVIER SHSN MAY
BE TNGT INTO THU WHEN FETCH BACKS SLIGHTLY AND INCREASES TO AROUND
100 MILES AND INVERSION HEIGHT INCREASES RESULTING IN GREAT LAKE
INDUCED CAPE.
WL CONVERT WINTER WX ADVY TO LAKE EFFECT SNOW ADVISORY AND EXPAND
NORTH TO INCLUDE REST OF LAKE SHORE AND WASHINGTON COUNTIES FOR
POTENTIAL OF 3 TO 5 INCHES TOTAL ADDITIONAL...WITH HIGHER AMOUNTS
LIKELY IN SOME SOUTHERN LAKESHORE AREAS BUT SPREAD OVER A GREATER
PERIOD. NOT ENOUGH CONFIDENCE AT THIS TIME TO INCREASE TO WARNING
BUT WL DEFINITELY NEED TO BE WATCHED...ESPECIALLY FOR TNGT AND
THU.
SHORT TERM...THURSDAY THROUGH FRIDAY NIGHT...FORECAST CONFIDENCE
IS HIGH.
LAKE EFFECT SNOW ADVISORY INTO THURSDAY ACROSS LOCATIONS NEAR
LAKE MICHIGAN. MODELS SHOWING MAIN SINGLE LAKE EFFECT SNOW BAND
SHIFTING SOUTHWARD THROUGH THE LAKESHORE COUNTIES THURSDAY
MORNING...THEN MOVING SOUTHWARD AND OUT OF THE AREA BY LATE
THURSDAY AFTERNOON. NAM MOST AGGRESSIVE WITH BRINGING IT FURTHEST
INLAND...WITH THE OTHER MODELS JUST GRAZING THE SHORELINE.
FAVORABLE SETUP CONTINUES THURSDAY WITH DELTA T VALUES OF 18 TO
21 DEGREES CELSIUS...SATURATED LOW LEVELS IN DENDRITE SNOW GROWTH
ZONE AND LOW LEVEL CONVERGENCE. CONTINUED HIGH POPS IN LAKESHORE
COUNTIES...LOWERING TO THE WEST.
SHOULD SEE ANOTHER 1 TO 2 INCHES OF SNOW NEAR THE LAKE WITH THIS
BAND. GIVEN SOME UNCERTAINTY WITH THE EXACT SETUP OF THE
BAND...COULD SEE HIGHER AMOUNTS THAN CURRENTLY FORECAST. THE REST
OF THE AREA WILL BE DRY...WITH COLD AND DRY AIRMASS IN PLACE.
HIGH PRESSURE PASSES SOUTHEAST THROUGH THE REGION THURSDAY
NIGHT. LIGHT WINDS AND CLEARING SKIES AND SOLID SNOWPACK SHOULD
ALLOW LOWS TO DROP INTO THE TEENS BELOW ZERO AWAY FROM THE
LAKE...SINGLE DIGITS BELOW ZERO NEAR IT. COULD EVEN BE A BIT
COLDER GIVEN THIS SETUP.
WARM AIR ADVECTION PATTERN THEN SETS UP ACROSS THE AREA FRIDAY AND
FRIDAY NIGHT...AS WINDS PICK UP OUT OF THE SOUTH SOUTHWEST. LOW
PRESSURE SHIFTS EAST ALONG THE CANADIAN BORDER. AIRMASS SHOULD
REMAIN DRY ACROSS THE AREA FOR MOST OF THIS PERIOD.
GFS/CANADIAN MODELS TRY TO BRING IN LIGHT QPF TO THE NORTH OR
NORTHWESTERN COUNTIES BY 12Z SATURDAY...WITH THE OTHERS DRY. LEFT
LOW POPS FOR LATER FRIDAY NIGHT. TEMPERATURES SHOULD REBOUND INTO
THE UPPER 20S TO LOWER 30S SATURDAY.
LONG TERM...SATURDAY THROUGH TUESDAY...FORECAST CONFIDENCE IS
MEDIUM.
COLD FRONT IS EXPECTED TO SHIFT SOUTHEAST THROUGH THE AREA
SATURDAY PER GFS...OR SATURDAY EVENING PER ECMWF. LOW PRESSURE
THEN STRENGTHENS AND SHIFTS FROM THE SOUTHERN PLAINS TO THE OHIO
RIVER VALLEY BY 00Z MONDAY...BEFORE MOVING FURTHER NORTHEAST
MONDAY NIGHT.
THE GFS IS FURTHER SOUTHEAST THAN THE ECMWF WITH THIS LOW
TRACK...WHICH KEEPS SOUTHERN WISCONSIN DRY. THE ECMWF IS NOT AS
FAR SOUTHEAST AS THE GFS...AND KEEPS THE SOUTHEAST COUNTIES ON THE
EDGE OF THE QPF SHIELD SATURDAY NIGHT INTO SUNDAY EVENING. SOME
UNCERTAINTY HERE WITH THE LOW TRACK. FOR NOW...USED CONSENSUS
POPS WHICH HAVE SLIGHT CHANCES FOR SNOW ACROSS MOST OF THE AREA.
STRONG COLD AIR ADVECTION SUNDAY INTO MONDAY WILL BRING THE
COLDEST AIRMASS SO FAR THIS WINTER SEASON INTO THE REGION.
1000/500MB THICKNESSES FALL IN THE 490S DECAMETER RANGE...WITH A
DRY AIRMASS IN PLACE. THIS SHOULD LEAD TO BITTER COLD TEMPERATURES
AND WIND CHILLS SUNDAY NIGHT INTO TUESDAY.
LOWERED TEMPERATURES SEVERAL DEGREES FROM THE CONSENSUS BLEND FOR
THIS PERIOD. FOR NOW...COULD SEE WIND CHILLS DROP INTO THE 25 TO
35 BELOW ZERO RANGE SUNDAY NIGHT...AND IN THE 30 TO 40 BELOW ZERO
RANGE MONDAY NIGHT AND INTO EARLY TUESDAY. TEMPERATURES WILL ALSO
DROP INTO THE TEENS TO NEAR 20 BELOW ZERO RANGE MONDAY NIGHT. WILL
CONTINUE TO WATCH THIS PERIOD FOR THE BITTER COLD TEMPERATURES
AND WIND CHILLS.
AVIATION/12Z TAFS/...
PERIODS OF LAKE EFFECT SNOW SHOWERS WILL AFFECT EASTERN TAF SITES
FOR THE DURATION OF THE PERIOD. SNOW SHOWERS COULD BE BRIEFLY
HEAVY TNGT INTO THU.
MARINE...
PERSISTENT NORTHEAST WINDS OF 10 TO 20 KNOTS WILL CAUSE HIGHER
WAVE HEIGHTS THROUGH THURSDAY. OCCASIONAL GUSTS TO 25 KNOTS ARE
ALSO LIKELY DUE TO TIGHTENING PRESSURE GRADIENT. WL CONTINUE SMALL
CRAFT ADVISORY BEGINNING THIS MORNING...AND EXTEND TO 00Z/03.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...LAKE EFFECT SNOW WARNING UNTIL 3 PM CST THURSDAY FOR WIZ066-071.
LAKE EFFECT SNOW ADVISORY UNTIL 3 PM CST THURSDAY FOR WIZ065-070-
072.
LAKE EFFECT SNOW ADVISORY UNTIL NOON CST THURSDAY FOR WIZ052-059-
060.
LM...LAKE EFFECT SNOW ADVISORY UNTIL NOON CST THURSDAY FOR LMZ643.
SMALL CRAFT ADVISORY UNTIL 6 PM CST THURSDAY FOR LMZ643>646.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...MBK
THURSDAY THROUGH TUESDAY...WOOD