Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/06/14
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1141 AM MST SAT JAN 4 2014
.UPDATE...
ISSUED AT 1139 AM MST SAT JAN 4 2014
WILL ISSUE A SNOW ADVISORY FOR ALL OF THE PIKES PEAK REGION. 2-4"
OF SNOW HAS BEEN REPORTED AND AN ADDITIONAL 2-4" WILL BE POSSIBLE
GIVEN TRENDS IN SAT PIX DATA AND HRRR GUIDANCE. SNOW OVER THE
PIKES PEAK REGION SHOULD DECREASE AROUND SUNSET.
UPDATE ISSUED AT 737 AM MST SAT JAN 4 2014
MADE SOME MINOR ADJUSTMENTS TO POPS AND SNOW AMOUNTS...AND UPDATED
MORNING TEMPS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 339 AM MST SAT JAN 4 2014
AN UPR TROF WL CONTINUE MOVING SOUTHEAST OVR THE AREA TODAY AND WL
MOVE OUT OF THE AREA BY LATE TONIGHT. THIS SYSTEM WL BRING MUCH
COLDER TEMPS TO THE AREA TODAY AND TONIGHT. A COLD FRONT ASSOCIATED
WITH THIS SYSTEM WL BE MOVING THRU SERN CO THIS MORNING...BRINGING
SOME GUSTY N TO NE WINDS. THE LATEST MODEL RUNS END UP WITH A MORE
EASTERLY...THAN NORTHERLY COMPONENT TO THE SFC WINDS BY LATER THIS
MORNING AND INTO THE AFTERNOON...PROVIDING A LITTLE BETTER
UPSLOPE...AT LEAST IN THE LOW LEVELS. THE MID LEVEL FLOW WL BE N TO
NW THIS AFTERNOON AND EVENING. LOW LEVEL MSTR WL BE INCREASING
BEHIND THE FRONT WITH LOW CLOUDS FORMING AND SNOW SPREADING
SOUTHWARD. THE CENTRAL MTS WL CONTINUE TO SEE SNOW THRU THE DAY.
THE CURRENT SNOW ADVISORY FOR THAT AREA STILL LOOKS GOOD. AS FOR
SNOW AMOUNTS OVR THE ERN MTS AND PLAINS...THE GFS AND NAM HAVE SOME
DIFFERENCES ALONG THE ARKANSAS RIVER VALLEY...WITH THE GFS BEING
HEAVIER WITH THE SNOW AMOUNTS. FOR THE REST OF THE AREA...THE GFS
IS ALSO A LITTLE HIGHER THAN THE NAM...BUT HAS THE SAME GENERAL
IDEA...WITH HIGHER AMOUNTS OVR THE PIKES PEAK...TELLER COUNTY AND
NRN EL PASO COUNTY AREAS AND ALONG THE SRN BORDER AREAS AND SERN
FOOTHILLS. WL GO WITH AMOUNTS THAT ARE GENERALLY IN BETWEEN THE NAM
AND GFS. IT LOOKS LIKE PIKE PEAK COULD SEE AMOUNTS THAT MEET
ADVISORY CRITERIA SO WL ISSUE THAT FROM LATE THIS MORNING INTO THE
EARLY EVENING HOURS.
TONIGHT...AS THE UPR TROF EXITS THE AREA TO THE SOUTH AND
EAST...PCPN CHANCES WL DECREASE OR END...EXCEPT THAT THE SRN BORDER
AREA AND SERN FOOTHILLS WL CONTINUE TO SEE SOME LIGHT SNOW INTO THE
LATE NIGHT HOURS. SOME LIGHT SNOW WL ALSO LIKELY CONTINUE OVR
PORTIONS OF THE CENTRAL CO MTS.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 339 AM MST SAT JAN 4 2014
SUNDAY...LONGWAVE TROUGH WILL BE SITUATED OVER THE MIDSECTION OF THE
COUNTRY SUNDAY MORNING...WHILE ACROSS THE CWA THE BRUNT OF SNOW
SHOULD BE ON THE WANE. ANOTHER LOBE OF ENERGY WILL ROTATE SOUTH
ACROSS THE STATE...BRINGING ANOTHER COLD FRONT DOWN ACROSS THE
PALMER DVD AND E PLAINS BY MIDDAY. THIS FRONT WILL HELP TO PRODUCE A
FEW ADDITIONAL SNOW SHOWERS FOR THE HIGHER TERRAIN AND PORTIONS OF
THE PLAINS THROUGH SUNDAY EVE...BUT SIGNIFICANT NEW ACCUMULATIONS
ARE NOT EXPECTED. TEMPS WILL STAY COLD HOWEVER...WITH THE ENTIRE
FORECAST AREA NOT EXPECTED TO BREAK 30 DEGREES.
MONDAY AND TUESDAY...SHORTWAVE RIDGING WILL SWEEP ACROSS THE STATE
ON MON BEFORE TRANSITIONING TO A MORE WESTERLY FLOW ALOFT. LATEST
NUMERICAL GUIDANCE INDICATES A SLIGHTLY WARMER SOLUTION FOR MON...SO
MAX TEMPS ON MON HAVE BEEN BOOSTED SLIGHTLY AND IF THE TREND
CONTINUES WILL HAVE TO BE WARMED EVEN FURTHER IN LATER FORECAST
PACKAGES. TEMPS ON TUE SHOULD WARM NICELY WITH THE INCREASING
WESTERLY FLOW...WITH MAX TEMPS PUSHING 50 F. ONGOING GRIDS HAVE DRY
CONDITIONS ON MON...WITH ISOLATED SNOW RETURNING TO THE CENTRAL MTS
TUE AFTN AND EVE...BUT LATEST MODEL SOLUTIONS NOW INDICATE DRY
CONDITIONS TO PERSIST A LITTLE LONGER...SO THIS PCPN THREAT WILL
MOST LIKELY BE DELAYED IN A LATER ISSUANCE.
WEDNESDAY THROUGH FRIDAY...GFS AND EC MODELS BOTH INDICATE AN
UNSETTLED PATTERN APPROACHING FOR THE LATTER HALF OF THE WORK
WEEK...WITH MULTIPLE UPPER DISTURBANCES CROSSING THE ROCKY MT
REGION. THE EXTENDED PROCEDURE OUTPUT OF MAX TEMPS IN THE MID 40S
FOR THE PLAINS...20S AND 30S FOR THE HIGH VALLEYS...AND A DAILY
ISOLATED THREAT OF SNOW FOR THE HIGHER TERRAIN LOOKS REASONABLE AT
THIS TIME. BOTH THE GFS AND EC HAVE BEEN WAVERING ON PLACEMENT AND
STRENGTH OF AN UPPER LOW IN THE THU/FRI TIME FRAME...SO CONFIDENCE
IN THE LONG RANGE IS LOW AT THIS TIME. MOORE
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1005 AM MST SAT JAN 4 2014
FOR KCOS...SNOW WILL CONTINUE THROUGH LATE AFTERNOON. EXPECT 1 TO
3 INCHES AT THE AIRPORT. SNOW WILL END BY EARLY EVENING WITH VFR
CONDITIONS BY LATE EVENING.
FOR KPUB...SNOW SHOWERS WILL CONTINUE INTO EARLY EVENING. MAY SEE
UP TO AN INCH OF SNOW. SKIES WILL CLEAR BY LATE EVENING.
FOR KALS...VFR THROUGH PERIOD. MAY SEE SOME SNOW SHOWERS LATER
THIS AFTERNOON AND EARLY EVENING WITH BRIEF MVFR.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 PM MST THIS EVENING FOR COZ081-
084-085.
WINTER WEATHER ADVISORY UNTIL 5 AM MST SUNDAY FOR COZ058-060.
WINTER WEATHER ADVISORY UNTIL 8 PM MST THIS EVENING FOR COZ082.
&&
$$
UPDATE...HODANISH
SHORT TERM...28
LONG TERM...MOORE
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1247 PM EST SAT JAN 4 2014
.SYNOPSIS...
HIGH PRESSURE WILL SLIDE EAST THROUGH TONIGHT. LOW PRESSURE MOVING
FROM THE GULF COAST STATES ON SUNDAY INTO QUEBEC BY MONDAY WILL
THEN DRAG A POTENT COLD FRONT THROUGH ON MONDAY. ARCTIC HIGH
PRESSURE WILL BUILDS IN LATER MONDAY THROUGH WEDNESDAY...THEN
SLIDE EAST WEDNESDAY NIGHT. A COLD FRONT WILL MOVE ACROSS ON
THURSDAY...FOLLOWED BY BUILDING HIGH PRESSURE ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TEMPS UP INTO THE UPPER TEENS ACROSS THE INTERIOR TO MID/UPPER 20S
ELSEWHERE. AS A RESULT...WIND CHILLS ARE CLIMBING INTO THE TEENS.
DEEP LAYERED RIDGE AXIS SLIDES TO THE EAST TODAY...WITH
ASSOCIATED SUBSIDENCE PROMOTING MINIMAL CLOUD COVER...EXCEPT OVER
FAR EASTERN ZONES WHERE WARM ADVECTION INDUCED MARINE STRATUS
BEGINS TO BUILD IN LATE IN THE AFTERNOON.
TEMPERATURES REBOUND TO THE MID 20S-AROUND 30 WITH DEEP LAYERED
SW FLOW SETTING UP BY AFTERNOON. HIGHS CONSISTENT WITH BLEND OF
MAV/MET GUIDANCE WITH NAM AND RUC 2-METER TEMPERATURES AND A MIX
DOWN FROM 950 HPA PER BUFKIT SOUNDINGS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
A COUPLE OF CONCERNS TONIGHT. 1ST...WITH WARM ADVECTION OVER THE
SNOW PACK - THERE IS THE POTENTIAL FOR AREAS OF FOG TO DEVELOP.
GIVEN RELATIVELY LIMITED LIQUID WATER CONTENT DO NOT EXPECT TO BE
DENSE - HOWEVER WITH TEMPERATURES BELOW FREEZING FOR ALL BUT
AROUND MONTAUK POINT - COULD SEE SOME FREEZING MIST. 2ND -
NAM/GFS/ECMWF ALL SHOW SOME DEGREE OF SATURATION ON THE 285K
ISENTROPIC SURFACE WITH WEAK TO MODERATE ISENTROPIC ASCENT - WHILE
RELATIVE DRY ALOFT. VERY OFTEN GET DRIZZLE OR LIGHT RAIN UNDER
THIS SCENARIO - SO SPOTTY -FZRA/-FZDZ IS POSSIBLE. THEN AS THE
COLUMN MOISTENS ALOFT - COULD ALSO SEE SOME -SN/-PL DEVELOP SUNDAY
MORNING UNTIL ALL PRECIPITATION TURNS TO RAIN BY MIDDAY.
FOR NOW CONFIDENCE IN EITHER IS NOT HIGH ENOUGH TO ISSUE A FREEZING
RAIN ADVISORY FOR ICE ACCRETION (NEED 80 PERCENT CONFIDENCE TO
ISSUE HEADLINE AND ONLY AT 30-50 PERCENT CONFIDENCE IN OCCURRENCE.
BEST CHANCE IS OVER NYC/LONG ISLAND WHERE LOW LEVELS SHOULD
SATURATE THE QUICKEST).
FOR LOWS TONIGHT AND HIGHS SUNDAY USED A BLEND OF MAV/MET
GUIDANCE WITH NAM 2-METER TEMPERATURES - ADJUSTING THE RATE OF
WARMING DOWNWARD TO ACCOUNT FOR IMPACT OF SNOW COVER. DO EXPECT
TEMPERATURES TO FALL OFF THIS EVENING - THEN LIKELY HOLD STEADY OR
EVEN RISE SLIGHTLY OVERNIGHT...THEN GRADUALLY RISE THROUGH THE DAY
ON SUNDAY. LOWS TONIGHT WILL BE NEAR NORMAL...AND HIGHS SUNDAY
AROUND 5 DEGREES ABOVE NORMAL.
ISENTROPIC LIFT AND SATURATION CONTINUES TO STRENGTHEN/DEEPEN
RESPECTIVELY SUNDAY NIGHT...AND REMAINS STRONG MONDAY MORNING.
HAVE THE POTENTIAL FOR MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL
IN THIS TIME FRAME. REFER TO HYDROLOGY SECTION FOR DETAILS ON
AMOUNTS AND POTENTIAL IMPACT.
PRECIPITATION TAPERS OFF BEHIND THE ARCTIC COLD FRONT MONDAY
AFTERNOON - AND SHARPLY COLDER AIR RUSHES IN BEHIND IT. GIVEN HOW
QUICKLY THE COLD AIR IS EXPECTED TO RUSH IN - HAVE SOME
POTENTIAL FOR A FLASH FREEZE - ESPECIALLY OVER AREAS TO THE N/W
OF NYC. ALWAYS TRICKY GAGING HOW FAST COLD AIR WORKS ITS WAY IN
OVER THE APPALACHIANS - BUT EXPECT DEPTH OF COLD AIR TO BE
SUFFICIENT THAT IT WILL MOVE IN FASTER THAN IS TYPICAL BEHIND MOST
COLD FRONTS (ABOUT A 6-12 HOUR DELAY). ALSO - GIVEN STRONG LOW
LEVEL WNW FLOW AND VERY COLD LOW LEVEL AIR WORKING IN - HAVE SOME
POTENTIAL FOR SOUND EFFECT SNOWS OVER THE EAST END OF LONG ISLAND
MONDAY NIGHT - FOR NOW JUST HAVE SLIGHT CHANCE POPS OVER THE S
FORK - BUT WILL CONTINUE TO MONITOR.
FOR LOWS SUNDAY NIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM
2-METER TEMPERATURES WITH VALUES 15-20 DEGREES ABOVE NORMAL. HIGHS
ON MONDAY WILL OCCUR DURING THE MORNING HOURS - CONSISTENT WITH A
BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES AND A MIX
DOWN FROM 900 HPA...EXCEPT 875 HPA WELL INLAND PER BUFKIT
SOUNDINGS. HIGHS SHOULD BE AROUND 5-10 DEGREES ABOVE NORMAL. USED
A BLEND OF NAM AND ECMWF 2-METER TEMPERATURES WITH
MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE FOR LOWS MONDAY NIGHT WITH VALUES
FORECAST TO BE 15 TO 20 DEGREES BELOW NORMAL. COUPLED WITH GUSTY
WNW WINDS - COULD SEE WIND CHILLS GENERALLY FROM -10 TO 0 - BUT
FROM -10 TO -20 TO THE N/W OF NYC. THERE IS ALSO A SMALL CHANCE
FOR WIND CHILLS AROUND -25 IN FAR NW ZONES - HAVE HIGHLIGHTED THIS
THREAT IN THE HWO.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
TUESDAY WILL BE BLUSTERY AND FRIGID WITH 850 TEMPERATURES OF -20
TO -24C SUPPORTING HIGHS ONLY FROM THE UPPER SINGLE DIGITS N/W OF
NYC TO THE MID TEENS ELSEWHERE - THIS IS SOME 20-30 DEGREES BELOW
NORMAL AND CONSISTENT WITH A BLEND OF MEX/MEN/EKD/ECM/ECE/WPC
GUIDANCE WITH ECMWF 2-METER TEMPERATURES. AFTERNOON WIND CHILL
READINGS SHOULD RANGE FROM -10 TO -20...EXCEPT TO AROUND 0 ACROSS
FAR E ZONES. WIND GUSTS COULD BE IN THE WIND ADVISORY RANGE DURING
THE DAY ON TUESDAY AS WELL. IN ADDITION - FLOW CONTINUES TO
SUPPORT POSSIBILITY OF SOUND EFFECT SNOWS OVER THE TWIN FORKS.
TROUGHING ALOFT LIFTS OUT OF THE NE TUESDAY NIGHT...ALLOWING FOR A
FAST WSW FLOW TO SET UP ALOFT WEDNESDAY-THURSDAY...BEFORE RIDGING
BUILDS BACK IN ON FRIDAY. FOR NOW IT APPEARS IT WILL BE DRY
TUESDAY NIGHT-WEDNESDAY NIGHT. HAVE THE POTENTIAL FOR SOME LIGHT
SNOW THURSDAY WITH WARM ADVECTION AHEAD OF A PASSING COLD
FRONT...AND ON THURSDAY NIGHT WITH A PASSING SHORTWAVE. FRIDAY
SHOULD BE DRY UNDER THE RIDGE.
FOR TEMPERATURES TUESDAY NIGHT-FRIDAY USED A BLEND OF
MEX/MEN/ECE/EKD/ECM/WPC GUIDANCE...WITH ECMWF 2-METER TEMPERATURES
MIXED IN THURSDAY-FRIDAY TO REFLECT DEEPER PENETRATION OF LOW
LEVEL COLD AIR BEHIND THE COLD FRONT THEN DEPICTED IN THE GFS.
TEMPERATURES WILL BE BELOW NORMAL THROUGH THURSDAY THEN NEAR NORMAL
ON FRIDAY. NOTE - LOWS TUESDAY NIGHT SHOULD BE AROUND 15 DEGREES
BELOW NORMAL AND HIGHS WEDNESDAY 10-15 DEGREES BELOW NORMAL.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
VFR THROUGH THIS EVENING AS HIGH PRESSURE MOVES OFF THE MID
ATLANTIC COAST.
SW SFC WINDS TODAY GENERALLY RIGHT DOWN 22 MAGNETIC. THERE COULD
BE AN ASOS REPORTED GUST TO UPPER TEENS AT JFK/EWR/LGA DURING THIS AFTN.
SW FLOW ALOFT OVERNIGHT BRINGS MARGINAL CIGS UP THE EAST COAST
AND INTO THE LOCAL AREA TOWARDS MORNING. INCLUDED VERY LIGHT FZDZ
FOR THE NYC METRO AND COASTAL TERMINALS IN THE EARLY MORNING...BUT
ONLY GIVE THIS A 50% CHC OF OCCURRENCE ATTM.
.OUTLOOK FOR 18Z SUNDAY THROUGH THU...
.SUN AFTN...MVFR > IFR. -RA. SE WND < 10 KT.
.SUN NGT-MON MORNING...IFR. RA BR.
.MON AFTN-TUE...BECOMING VFR MON AFTN. W WND G25-35KT...HIGHEST
TUE AFTN.
.WED...VFR. W WINDS G20KT.
.THU...VFR. CHC MVFR -SN LATE.
&&
.MARINE...
ANZ350 DOWN BELOW SCA CONDS...BUT MAY BE CLOSE FROM TIME TO TIME
INTO THE AFTERNOON.
CONDS MAY BRIEFLY BUILD TO SCA CONDS FOR A FEW HOURS THIS
EVENING...BUT WILL NOT CARRY HEADLINES ATTM.
INCREASING SOUTHERLY FLOW ON SUNDAY WILL RESULT IN WIDESPREAD SCA
CONDS ON THE OCEAN WATERS SUNDAY NIGHT THROUGH MONDAY. SCA LIKELY
ON MONDAY FOR THE REST OF THE WATERS.
AFTER A STRONG COLD FROPA MON MORNING...WESTERLY GALES SHOULD
DEVELOP ON THE OCEAN WATERS MON AFTERNOON AND SPREAD TO ALL WATERS
MON NIGHT-TUE. THESE WINDS WILL SLOWLY DIMINISH TUE NIGHT...WITH
LINGERING SCA CONDS ON ALL WATERS WED MORNING AND ON THE EASTERN
OCEAN/SOUND/BAYS WED AFTERNOON AND POSSIBLY INTO WED NIGHT.
&&
.HYDROLOGY...
ANOTHER WIDESPREAD SIGNIFICANT PRECIP EVENT IS POSSIBLE SUNDAY
THROUGH EARLY MONDAY...MOSTLY IN THE FORM OF RAIN. THE HEAVY RAIN
COULD COMBINE WITH RESIDUAL SNOW COVER TO PRODUCE SOME MINOR
FLOODING. GENERAL ESTIMATES OF EVENT TOTAL LIQUID AMOUNTS FROM A
MODEL CONSENSUS ARE AROUND 2/3 TO 9/10 OF AN INCH.
&&
.CLIMATE...
CLIMATE RECORDS FOR JANUARY 4:
LOCATION RECORD LOW FORECAST VALUE
BRIDGEPORT...CT -1 1981 2
ISLIP...NY 10 2008 -1
LAGUARDIA...NY 4 1981 8
JFK AIRPORT...NY 8 1981 5
NYC-CENTRAL PARK...NY -3 1918 7
NEWARK...NJ 1 1981 3
&&
.EQUIPMENT...
THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS
OUT OF SERVICE.
DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY
BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER
RADIO STATION KWO35 IS OUT OF SERVICE.
DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE
INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO
DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE
WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE
INTERFERENCE ISSUE HAS BEEN RESOLVED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM SUNDAY TO 6 PM EST MONDAY FOR
ANZ350-353-355.
&&
$$
SYNOPSIS...MALOIT
NEAR TERM...MPS
SHORT TERM...MALOIT
LONG TERM...MALOIT
AVIATION...TONGUE
MARINE...GOODMAN/MALOIT
HYDROLOGY...MALOIT
CLIMATE...
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1223 PM EST SAT JAN 4 2014
.SYNOPSIS...
HIGH PRESSURE WILL SLIDE EAST THROUGH TONIGHT. LOW PRESSURE MOVING
FROM THE GULF COAST STATES ON SUNDAY INTO QUEBEC BY MONDAY WILL
THEN DRAG A POTENT COLD FRONT THROUGH ON MONDAY. ARCTIC HIGH
PRESSURE WILL BUILDS IN LATER MONDAY THROUGH WEDNESDAY...THEN
SLIDE EAST WEDNESDAY NIGHT. A COLD FRONT WILL MOVE ACROSS ON
THURSDAY...FOLLOWED BY BUILDING HIGH PRESSURE ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TEMPS UP INTO THE UPPER TEENS ACROSS THE INTERIOR TO MID/UPPER 20S
ELSEWHERE. AS A RESULT...WIND CHILLS ARE CLIMBING INTO THE TEENS.
DEEP LAYERED RIDGE AXIS SLIDES TO THE EAST TODAY...WITH
ASSOCIATED SUBSIDENCE PROMOTING MINIMAL CLOUD COVER...EXCEPT OVER
FAR EASTERN ZONES WHERE WARM ADVECTION INDUCED MARINE STRATUS
BEGINS TO BUILD IN LATE IN THE AFTERNOON.
TEMPERATURES REBOUND TO THE MID 20S-AROUND 30 WITH DEEP LAYERED
SW FLOW SETTING UP BY AFTERNOON. HIGHS CONSISTENT WITH BLEND OF
MAV/MET GUIDANCE WITH NAM AND RUC 2-METER TEMPERATURES AND A MIX
DOWN FROM 950 HPA PER BUFKIT SOUNDINGS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
A COUPLE OF CONCERNS TONIGHT. 1ST...WITH WARM ADVECTION OVER THE
SNOW PACK - THERE IS THE POTENTIAL FOR AREAS OF FOG TO DEVELOP.
GIVEN RELATIVELY LIMITED LIQUID WATER CONTENT DO NOT EXPECT TO BE
DENSE - HOWEVER WITH TEMPERATURES BELOW FREEZING FOR ALL BUT
AROUND MONTAUK POINT - COULD SEE SOME FREEZING MIST. 2ND -
NAM/GFS/ECMWF ALL SHOW SOME DEGREE OF SATURATION ON THE 285K
ISENTROPIC SURFACE WITH WEAK TO MODERATE ISENTROPIC ASCENT - WHILE
RELATIVE DRY ALOFT. VERY OFTEN GET DRIZZLE OR LIGHT RAIN UNDER
THIS SCENARIO - SO SPOTTY -FZRA/-FZDZ IS POSSIBLE. THEN AS THE
COLUMN MOISTENS ALOFT - COULD ALSO SEE SOME -SN/-PL DEVELOP SUNDAY
MORNING UNTIL ALL PRECIPITATION TURNS TO RAIN BY MIDDAY.
FOR NOW CONFIDENCE IN EITHER IS NOT HIGH ENOUGH TO ISSUE A FREEZING
RAIN ADVISORY FOR ICE ACCRETION (NEED 80 PERCENT CONFIDENCE TO
ISSUE HEADLINE AND ONLY AT 30-50 PERCENT CONFIDENCE IN OCCURRENCE.
BEST CHANCE IS OVER NYC/LONG ISLAND WHERE LOW LEVELS SHOULD
SATURATE THE QUICKEST).
FOR LOWS TONIGHT AND HIGHS SUNDAY USED A BLEND OF MAV/MET
GUIDANCE WITH NAM 2-METER TEMPERATURES - ADJUSTING THE RATE OF
WARMING DOWNWARD TO ACCOUNT FOR IMPACT OF SNOW COVER. DO EXPECT
TEMPERATURES TO FALL OFF THIS EVENING - THEN LIKELY HOLD STEADY OR
EVEN RISE SLIGHTLY OVERNIGHT...THEN GRADUALLY RISE THROUGH THE DAY
ON SUNDAY. LOWS TONIGHT WILL BE NEAR NORMAL...AND HIGHS SUNDAY
AROUND 5 DEGREES ABOVE NORMAL.
ISENTROPIC LIFT AND SATURATION CONTINUES TO STRENGTHEN/DEEPEN
RESPECTIVELY SUNDAY NIGHT...AND REMAINS STRONG MONDAY MORNING.
HAVE THE POTENTIAL FOR MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL
IN THIS TIME FRAME. REFER TO HYDROLOGY SECTION FOR DETAILS ON
AMOUNTS AND POTENTIAL IMPACT.
PRECIPITATION TAPERS OFF BEHIND THE ARCTIC COLD FRONT MONDAY
AFTERNOON - AND SHARPLY COLDER AIR RUSHES IN BEHIND IT. GIVEN HOW
QUICKLY THE COLD AIR IS EXPECTED TO RUSH IN - HAVE SOME
POTENTIAL FOR A FLASH FREEZE - ESPECIALLY OVER AREAS TO THE N/W
OF NYC. ALWAYS TRICKY GAGING HOW FAST COLD AIR WORKS ITS WAY IN
OVER THE APPALACHIANS - BUT EXPECT DEPTH OF COLD AIR TO BE
SUFFICIENT THAT IT WILL MOVE IN FASTER THAN IS TYPICAL BEHIND MOST
COLD FRONTS (ABOUT A 6-12 HOUR DELAY). ALSO - GIVEN STRONG LOW
LEVEL WNW FLOW AND VERY COLD LOW LEVEL AIR WORKING IN - HAVE SOME
POTENTIAL FOR SOUND EFFECT SNOWS OVER THE EAST END OF LONG ISLAND
MONDAY NIGHT - FOR NOW JUST HAVE SLIGHT CHANCE POPS OVER THE S
FORK - BUT WILL CONTINUE TO MONITOR.
FOR LOWS SUNDAY NIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM
2-METER TEMPERATURES WITH VALUES 15-20 DEGREES ABOVE NORMAL. HIGHS
ON MONDAY WILL OCCUR DURING THE MORNING HOURS - CONSISTENT WITH A
BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES AND A MIX
DOWN FROM 900 HPA...EXCEPT 875 HPA WELL INLAND PER BUFKIT
SOUNDINGS. HIGHS SHOULD BE AROUND 5-10 DEGREES ABOVE NORMAL. USED
A BLEND OF NAM AND ECMWF 2-METER TEMPERATURES WITH
MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE FOR LOWS MONDAY NIGHT WITH VALUES
FORECAST TO BE 15 TO 20 DEGREES BELOW NORMAL. COUPLED WITH GUSTY
WNW WINDS - COULD SEE WIND CHILLS GENERALLY FROM -10 TO 0 - BUT
FROM -10 TO -20 TO THE N/W OF NYC. THERE IS ALSO A SMALL CHANCE
FOR WIND CHILLS AROUND -25 IN FAR NW ZONES - HAVE HIGHLIGHTED THIS
THREAT IN THE HWO.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
TUESDAY WILL BE BLUSTERY AND FRIGID WITH 850 TEMPERATURES OF -20
TO -24C SUPPORTING HIGHS ONLY FROM THE UPPER SINGLE DIGITS N/W OF
NYC TO THE MID TEENS ELSEWHERE - THIS IS SOME 20-30 DEGREES BELOW
NORMAL AND CONSISTENT WITH A BLEND OF MEX/MEN/EKD/ECM/ECE/WPC
GUIDANCE WITH ECMWF 2-METER TEMPERATURES. AFTERNOON WIND CHILL
READINGS SHOULD RANGE FROM -10 TO -20...EXCEPT TO AROUND 0 ACROSS
FAR E ZONES. WIND GUSTS COULD BE IN THE WIND ADVISORY RANGE DURING
THE DAY ON TUESDAY AS WELL. IN ADDITION - FLOW CONTINUES TO
SUPPORT POSSIBILITY OF SOUND EFFECT SNOWS OVER THE TWIN FORKS.
TROUGHING ALOFT LIFTS OUT OF THE NE TUESDAY NIGHT...ALLOWING FOR A
FAST WSW FLOW TO SET UP ALOFT WEDNESDAY-THURSDAY...BEFORE RIDGING
BUILDS BACK IN ON FRIDAY. FOR NOW IT APPEARS IT WILL BE DRY
TUESDAY NIGHT-WEDNESDAY NIGHT. HAVE THE POTENTIAL FOR SOME LIGHT
SNOW THURSDAY WITH WARM ADVECTION AHEAD OF A PASSING COLD
FRONT...AND ON THURSDAY NIGHT WITH A PASSING SHORTWAVE. FRIDAY
SHOULD BE DRY UNDER THE RIDGE.
FOR TEMPERATURES TUESDAY NIGHT-FRIDAY USED A BLEND OF
MEX/MEN/ECE/EKD/ECM/WPC GUIDANCE...WITH ECMWF 2-METER TEMPERATURES
MIXED IN THURSDAY-FRIDAY TO REFLECT DEEPER PENETRATION OF LOW
LEVEL COLD AIR BEHIND THE COLD FRONT THEN DEPICTED IN THE GFS.
TEMPERATURES WILL BE BELOW NORMAL THROUGH THURSDAY THEN NEAR NORMAL
ON FRIDAY. NOTE - LOWS TUESDAY NIGHT SHOULD BE AROUND 15 DEGREES
BELOW NORMAL AND HIGHS WEDNESDAY 10-15 DEGREES BELOW NORMAL.
&&
.AVIATION /17Z SATURDAY THROUGH WEDNESDAY/...
VFR TODAY AS HIGH PRESSURE MOVES OFF THE MID ATLANTIC COAST.
SW SFC WINDS TODAY GENERALLY RIGHT DOWN 22 MAGNETIC. THERE COULD
BE AN ASOS REPORTED GUST TO UPPER TEENS AT JFK/EWR/LGA DURING THE
AFTN.
SOUTHERLY FLOW OVERNIGHT BRINGS MARGINAL CIGS UP THE EAST COAST
AND INTO THE LOCAL AREA BY MORNING. CHC FOR SOME FREEZING DRIZZLE
TO THE NYC METRO AND COASTAL TERMINALS IN THE PREDAWN HOURS ON
SUNDAY.
.OUTLOOK FOR 12Z SUNDAY THROUGH WED...
.SUN...MVFR. CHC FREEZING DRIZZLE EARLY...-RA AFTN. SE WND < 10
KT.
.SUN NGT-MON MORNING...IFR. RA. LLWS ALSO POSSIBLE WITH S-SW
WINDS INCREASING TO 40-45 KT AT FL015.
.MON AFTN-TUE...BECOMING VFR MON AFTN. W WND G25-35KT...HIGHEST
TUE AFTN.
.WED...VFR. W WINDS G20KT.
&&
.MARINE...
ANZ350 DOWN BELOW SCA CONDS...BUT MAY BE CLOSE FROM TIME TO TIME
INTO THE AFTERNOON.
CONDS MAY BRIEFLY BUILD TO SCA CONDS FOR A FEW HOURS THIS
EVENING...BUT WILL NOT CARRY HEADLINES ATTM.
INCREASING SOUTHERLY FLOW ON SUNDAY WILL RESULT IN WIDESPREAD SCA
CONDS ON THE OCEAN WATERS SUNDAY NIGHT THROUGH MONDAY. SCA LIKELY
ON MONDAY FOR THE REST OF THE WATERS.
AFTER A STRONG COLD FROPA MON MORNING...WESTERLY GALES SHOULD
DEVELOP ON THE OCEAN WATERS MON AFTERNOON AND SPREAD TO ALL WATERS
MON NIGHT-TUE. THESE WINDS WILL SLOWLY DIMINISH TUE NIGHT...WITH
LINGERING SCA CONDS ON ALL WATERS WED MORNING AND ON THE EASTERN
OCEAN/SOUND/BAYS WED AFTERNOON AND POSSIBLY INTO WED NIGHT.
&&
.HYDROLOGY...
ANOTHER WIDESPREAD SIGNIFICANT PRECIP EVENT IS POSSIBLE SUNDAY
THROUGH EARLY MONDAY...MOSTLY IN THE FORM OF RAIN. THE HEAVY RAIN
COULD COMBINE WITH RESIDUAL SNOW COVER TO PRODUCE SOME MINOR
FLOODING. GENERAL ESTIMATES OF EVENT TOTAL LIQUID AMOUNTS FROM A
MODEL CONSENSUS ARE AROUND 2/3 TO 9/10 OF AN INCH.
&&
.CLIMATE...
CLIMATE RECORDS FOR JANUARY 4:
LOCATION RECORD LOW FORECAST VALUE
BRIDGEPORT...CT -1 1981 2
ISLIP...NY 10 2008 -1
LAGUARDIA...NY 4 1981 8
JFK AIRPORT...NY 8 1981 5
NYC-CENTRAL PARK...NY -3 1918 7
NEWARK...NJ 1 1981 3
&&
.EQUIPMENT...
THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS
OUT OF SERVICE.
DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY
BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER
RADIO STATION KWO35 IS OUT OF SERVICE.
DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE
INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO
DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE
WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE
INTERFERENCE ISSUE HAS BEEN RESOLVED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM SUNDAY TO 6 PM EST MONDAY FOR
ANZ350-353-355.
&&
$$
SYNOPSIS...MALOIT
NEAR TERM...MALOIT/MPS
SHORT TERM...MALOIT
LONG TERM...MALOIT
AVIATION...TONGUE
MARINE...GOODMAN/MALOIT
HYDROLOGY...MALOIT
CLIMATE...
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
951 AM EST SAT JAN 4 2014
.SYNOPSIS...
HIGH PRESSURE WILL SLIDE EAST THROUGH TONIGHT. LOW PRESSURE MOVING
FROM THE GULF COAST STATES ON SUNDAY INTO QUEBEC BY MONDAY WILL
THEN DRAG A POTENT COLD FRONT THROUGH ON MONDAY. ARCTIC HIGH
PRESSURE WILL BUILDS IN LATER MONDAY THROUGH WEDNESDAY...THEN
SLIDE EAST WEDNESDAY NIGHT. A COLD FRONT WILL MOVE ACROSS ON
THURSDAY...FOLLOWED BY BUILDING HIGH PRESSURE ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TEMPS BEGINNING TO WARM...BUT WILL BE SLOW DUE TO THE FRESH
SNOWPACK AND UNUSUALLY COLD AIRMASS OVER THE REGION. TEMPS IN THE
LOCAL AREA HAVE RISEN TO ABOVE ZERO...AND SHOULD BE IN THE 20S BY
MIDDAY. WIND CHILLS IN THE SINGLE DIGITS TO JUST BELOW ZERO WILL
RISE INTO THE TEENS.
DEEP LAYERED RIDGE AXIS SLIDES TO THE EAST TODAY...WITH ASSOCIATED
SUBSIDENCE PROMOTING MINIMAL CLOUD COVER...EXCEPT OVER FAR EASTERN
ZONES WHERE WARM ADVECTION INDUCED MARINE STRATUS BEGINS TO BUILD
IN LATE IN THE AFTERNOON.
TEMPERATURES REBOUND TO THE MID 20S-AROUND 30 WITH DEEP LAYERED
SW FLOW SETTING UP BY AFTERNOON. HIGHS CONSISTENT WITH BLEND OF
MAV/MET GUIDANCE WITH NAM AND RUC 2-METER TEMPERATURES AND A MIX
DOWN FROM 950 HPA PER BUFKIT SOUNDINGS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
A COUPLE OF CONCERNS TONIGHT. 1ST...WITH WARM ADVECTION OVER THE
SNOW PACK - THERE IS THE POTENTIAL FOR AREAS OF FOG TO DEVELOP.
GIVEN RELATIVELY LIMITED LIQUID WATER CONTENT DO NOT EXPECT TO BE
DENSE - HOWEVER WITH TEMPERATURES BELOW FREEZING FOR ALL BUT
AROUND MONTAUK POINT - COULD SEE SOME FREEZING MIST. 2ND -
NAM/GFS/ECMWF ALL SHOW SOME DEGREE OF SATURATION ON THE 285K
ISENTROPIC SURFACE WITH WEAK TO MODERATE ISENTROPIC ASCENT - WHILE
RELATIVE DRY ALOFT. VERY OFTEN GET DRIZZLE OR LIGHT RAIN UNDER
THIS SCENARIO - SO SPOTTY -FZRA/-FZDZ IS POSSIBLE. THEN AS THE
COLUMN MOISTENS ALOFT - COULD ALSO SEE SOME -SN/-PL DEVELOP SUNDAY
MORNING UNTIL ALL PRECIPITATION TURNS TO RAIN BY MIDDAY.
FOR NOW CONFIDENCE IN EITHER IS NOT HIGH ENOUGH TO ISSUE A FREEZING
RAIN ADVISORY FOR ICE ACCRETION (NEED 80 PERCENT CONFIDENCE TO
ISSUE HEADLINE AND ONLY AT 30-50 PERCENT CONFIDENCE IN OCCURRENCE.
BEST CHANCE IS OVER NYC/LONG ISLAND WHERE LOW LEVELS SHOULD
SATURATE THE QUICKEST).
FOR LOWS TONIGHT AND HIGHS SUNDAY USED A BLEND OF MAV/MET
GUIDANCE WITH NAM 2-METER TEMPERATURES - ADJUSTING THE RATE OF
WARMING DOWNWARD TO ACCOUNT FOR IMPACT OF SNOW COVER. DO EXPECT
TEMPERATURES TO FALL OFF THIS EVENING - THEN LIKELY HOLD STEADY OR
EVEN RISE SLIGHTLY OVERNIGHT...THEN GRADUALLY RISE THROUGH THE DAY
ON SUNDAY. LOWS TONIGHT WILL BE NEAR NORMAL...AND HIGHS SUNDAY
AROUND 5 DEGREES ABOVE NORMAL.
ISENTROPIC LIFT AND SATURATION CONTINUES TO STRENGTHEN/DEEPEN
RESPECTIVELY SUNDAY NIGHT...AND REMAINS STRONG MONDAY MORNING.
HAVE THE POTENTIAL FOR MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL
IN THIS TIME FRAME. REFER TO HYDROLOGY SECTION FOR DETAILS ON
AMOUNTS AND POTENTIAL IMPACT.
PRECIPITATION TAPERS OFF BEHIND THE ARCTIC COLD FRONT MONDAY
AFTERNOON - AND SHARPLY COLDER AIR RUSHES IN BEHIND IT. GIVEN HOW
QUICKLY THE COLD AIR IS EXPECTED TO RUSH IN - HAVE SOME
POTENTIAL FOR A FLASH FREEZE - ESPECIALLY OVER AREAS TO THE N/W
OF NYC. ALWAYS TRICKY GAGING HOW FAST COLD AIR WORKS ITS WAY IN
OVER THE APPALACHIANS - BUT EXPECT DEPTH OF COLD AIR TO BE
SUFFICIENT THAT IT WILL MOVE IN FASTER THAN IS TYPICAL BEHIND MOST
COLD FRONTS (ABOUT A 6-12 HOUR DELAY). ALSO - GIVEN STRONG LOW
LEVEL WNW FLOW AND VERY COLD LOW LEVEL AIR WORKING IN - HAVE SOME
POTENTIAL FOR SOUND EFFECT SNOWS OVER THE EAST END OF LONG ISLAND
MONDAY NIGHT - FOR NOW JUST HAVE SLIGHT CHANCE POPS OVER THE S
FORK - BUT WILL CONTINUE TO MONITOR.
FOR LOWS SUNDAY NIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM
2-METER TEMPERATURES WITH VALUES 15-20 DEGREES ABOVE NORMAL. HIGHS
ON MONDAY WILL OCCUR DURING THE MORNING HOURS - CONSISTENT WITH A
BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES AND A MIX
DOWN FROM 900 HPA...EXCEPT 875 HPA WELL INLAND PER BUFKIT
SOUNDINGS. HIGHS SHOULD BE AROUND 5-10 DEGREES ABOVE NORMAL. USED
A BLEND OF NAM AND ECMWF 2-METER TEMPERATURES WITH
MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE FOR LOWS MONDAY NIGHT WITH VALUES
FORECAST TO BE 15 TO 20 DEGREES BELOW NORMAL. COUPLED WITH GUSTY
WNW WINDS - COULD SEE WIND CHILLS GENERALLY FROM -10 TO 0 - BUT
FROM -10 TO -20 TO THE N/W OF NYC. THERE IS ALSO A SMALL CHANCE
FOR WIND CHILLS AROUND -25 IN FAR NW ZONES - HAVE HIGHLIGHTED THIS
THREAT IN THE HWO.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
TUESDAY WILL BE BLUSTERY AND FRIGID WITH 850 TEMPERATURES OF -20
TO -24C SUPPORTING HIGHS ONLY FROM THE UPPER SINGLE DIGITS N/W OF
NYC TO THE MID TEENS ELSEWHERE - THIS IS SOME 20-30 DEGREES BELOW
NORMAL AND CONSISTENT WITH A BLEND OF MEX/MEN/EKD/ECM/ECE/WPC
GUIDANCE WITH ECMWF 2-METER TEMPERATURES. AFTERNOON WIND CHILL
READINGS SHOULD RANGE FROM -10 TO -20...EXCEPT TO AROUND 0 ACROSS
FAR E ZONES. WIND GUSTS COULD BE IN THE WIND ADVISORY RANGE DURING
THE DAY ON TUESDAY AS WELL. IN ADDITION - FLOW CONTINUES TO
SUPPORT POSSIBILITY OF SOUND EFFECT SNOWS OVER THE TWIN FORKS.
TROUGHING ALOFT LIFTS OUT OF THE NE TUESDAY NIGHT...ALLOWING FOR A
FAST WSW FLOW TO SET UP ALOFT WEDNESDAY-THURSDAY...BEFORE RIDGING
BUILDS BACK IN ON FRIDAY. FOR NOW IT APPEARS IT WILL BE DRY
TUESDAY NIGHT-WEDNESDAY NIGHT. HAVE THE POTENTIAL FOR SOME LIGHT
SNOW THURSDAY WITH WARM ADVECTION AHEAD OF A PASSING COLD
FRONT...AND ON THURSDAY NIGHT WITH A PASSING SHORTWAVE. FRIDAY
SHOULD BE DRY UNDER THE RIDGE.
FOR TEMPERATURES TUESDAY NIGHT-FRIDAY USED A BLEND OF
MEX/MEN/ECE/EKD/ECM/WPC GUIDANCE...WITH ECMWF 2-METER TEMPERATURES
MIXED IN THURSDAY-FRIDAY TO REFLECT DEEPER PENETRATION OF LOW
LEVEL COLD AIR BEHIND THE COLD FRONT THEN DEPICTED IN THE GFS.
TEMPERATURES WILL BE BELOW NORMAL THROUGH THURSDAY THEN NEAR NORMAL
ON FRIDAY. NOTE - LOWS TUESDAY NIGHT SHOULD BE AROUND 15 DEGREES
BELOW NORMAL AND HIGHS WEDNESDAY 10-15 DEGREES BELOW NORMAL.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
VFR TODAY AS HIGH PRESSURE MOVES OFF THE MID ATLANTIC COAST.
SW SFC WINDS TODAY GENERALLY RIGHT DOWN 22 MAGNETIC. THERE COULD
BE AN ASOS REPORTED GUST TO UPPER TEENS AT JFK/EWR/LGA DURING THE
AFTN.
SOUTHERLY FLOW OVERNIGHT BRINGS MARGINAL CIGS UP THE EAST COAST
AND INTO THE LOCAL AREA BY MORNING. CHC FOR SOME FREEZING DRIZZLE
TO THE NYC METRO AND COASTAL TERMINALS IN THE PREDAWN HOURS ON
SUNDAY.
.OUTLOOK FOR 12Z SUNDAY THROUGH WED...
.SUN...MVFR. CHC FREEZING DRIZZLE EARLY...-RA AFTN. SE WND < 10
KT.
.SUN NGT-MON MORNING...IFR. RA. LLWS ALSO POSSIBLE WITH S-SW
WINDS INCREASING TO 40-45 KT AT FL015.
.MON AFTN-TUE...BECOMING VFR MON AFTN. W WND G25-35KT...HIGHEST
TUE AFTN.
.WED...VFR. W WINDS G20KT.
&&
.MARINE...
THERE IS SOME POTENTIAL ANZ-350 COULD HAVE A FEW HOURS LATE THIS
MORNING/EARLY THIS AFTERNOON WITH SEAS BELOW 5 FT THROUGHOUT THE
ZONE. HOWEVER...THIS LULL DOES NOT APPEAR IT WILL BE LONG ENOUGH
TO ADJUST THE EXISTING SCA ANY. STILL APPEAR ON TRACK FOR SEAS TO
BUILD BACK TO 5 FT BY LATE AFTERNOON IN ANZ-350.
INCREASING SW FLOW SHOULD BUILD OCEAN SEAS BACK TO 5 FT ON MOST
IF NOT ALL OCEAN WATERS TONIGHT. STEADY SE-S FLOW 15-20 KT SHOULD
THEN MAINTAIN SCA CONDS ON THE OCEAN ESPECIALLY OUT EAST INTO MON
MORNING.
AFTER A STRONG COLD FROPA MON MORNING...WESTERLY GALES SHOULD
DEVELOP ON THE OCEAN WATERS MON AFTERNOON AND SPREAD TO ALL WATERS
MON NIGHT-TUE. THESE WINDS WILL SLOWLY DIMINISH TUE NIGHT...WITH
LINGERING SCA CONDS ON ALL WATERS WED MORNING AND ON THE EASTERN
OCEAN/SOUND/BAYS WED AFTERNOON AND POSSIBLY INTO WED NIGHT.
&&
.HYDROLOGY...
ANOTHER WIDESPREAD SIGNIFICANT PRECIP EVENT IS POSSIBLE SUNDAY
THROUGH EARLY MONDAY...MOSTLY IN THE FORM OF RAIN. THE HEAVY RAIN
COULD COMBINE WITH RESIDUAL SNOW COVER TO PRODUCE SOME MINOR
FLOODING. GENERAL ESTIMATES OF EVENT TOTAL LIQUID AMOUNTS FROM A
MODEL CONSENSUS ARE AROUND 2/3 TO 9/10 OF AN INCH.
&&
.CLIMATE...
CLIMATE RECORDS FOR JANUARY 4:
LOCATION RECORD LOW FORECAST VALUE
BRIDGEPORT...CT -1 1981 2
ISLIP...NY 10 2008 -1
LAGUARDIA...NY 4 1981 8
JFK AIRPORT...NY 8 1981 5
NYC-CENTRAL PARK...NY -3 1918 7
NEWARK...NJ 1 1981 3
&&
.EQUIPMENT...
THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS
OUT OF SERVICE.
DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY
BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER
RADIO STATION KWO35 IS OUT OF SERVICE.
DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE
INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO
DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE
WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE
INTERFERENCE ISSUE HAS BEEN RESOLVED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST MONDAY FOR ANZ350.
&&
$$
SYNOPSIS...MALOIT
NEAR TERM...MALOIT/MPS
SHORT TERM...MALOIT
LONG TERM...MALOIT
AVIATION...TONGUE
MARINE...GOODMAN/MALOIT
HYDROLOGY...MALOIT
CLIMATE...
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
924 AM EST SAT JAN 4 2014
.SYNOPSIS...
HIGH PRESSURE WILL SLIDE EAST THROUGH TONIGHT. LOW PRESSURE MOVING
FROM THE GULF COAST STATES ON SUNDAY INTO QUEBEC BY MONDAY WILL
THEN DRAG A POTENT COLD FRONT THROUGH ON MONDAY. ARCTIC HIGH
PRESSURE WILL BUILDS IN LATER MONDAY THROUGH WEDNESDAY...THEN
SLIDE EAST WEDNESDAY NIGHT. A COLD FRONT WILL MOVE ACROSS ON
THURSDAY...FOLLOWED BY BUILDING HIGH PRESSURE ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TEMPS BEGINNING TO WARM...BUT WILL BE SLOW DUE TO THE FRESH
SNOWPACK AND UNUSUALLY COLD AIRMASS OVER THE REGION. TEMPS IN THE
LOCAL AREA HAVE RISEN TO ABOVE ZERO...AND SHOULD BE IN THE 20S BY
MIDDAY. WIND CHILLS IN THE SINGLE DIGITS TO JUST BELOW ZERO WILL
RISE INTO THE TEENS.
DEEP LAYERED RIDGE AXIS SLIDES TO THE EAST TODAY...WITH ASSOCIATED
SUBSIDENCE PROMOTING MINIMAL CLOUD COVER...EXCEPT OVER FAR EASTERN
ZONES WHERE WARM ADVECTION INDUCED MARINE STRATUS BEGINS TO BUILD
IN LATE IN THE AFTERNOON.
TEMPERATURES REBOUND TO THE MID 20S-AROUND 30 WITH DEEP LAYERED
SW FLOW SETTING UP BY AFTERNOON. HIGHS CONSISTENT WITH BLEND OF
MAV/MET GUIDANCE WITH NAM AND RUC 2-METER TEMPERATURES AND A MIX
DOWN FROM 950 HPA PER BUFKIT SOUNDINGS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
A COUPLE OF CONCERNS TONIGHT. 1ST...WITH WARM ADVECTION OVER THE
SNOW PACK - THERE IS THE POTENTIAL FOR AREAS OF FOG TO DEVELOP.
GIVEN RELATIVELY LIMITED LIQUID WATER CONTENT DO NOT EXPECT TO BE
DENSE - HOWEVER WITH TEMPERATURES BELOW FREEZING FOR ALL BUT
AROUND MONTAUK POINT - COULD SEE SOME FREEZING MIST. 2ND -
NAM/GFS/ECMWF ALL SHOW SOME DEGREE OF SATURATION ON THE 285K
ISENTROPIC SURFACE WITH WEAK TO MODERATE ISENTROPIC ASCENT - WHILE
RELATIVE DRY ALOFT. VERY OFTEN GET DRIZZLE OR LIGHT RAIN UNDER
THIS SCENARIO - SO SPOTTY -FZRA/-FZDZ IS POSSIBLE. THEN AS THE
COLUMN MOISTENS ALOFT - COULD ALSO SEE SOME -SN/-PL DEVELOP SUNDAY
MORNING UNTIL ALL PRECIPITATION TURNS TO RAIN BY MIDDAY.
FOR NOW CONFIDENCE IN EITHER IS NOT HIGH ENOUGH TO ISSUE A FREEZING
RAIN ADVISORY FOR ICE ACCRETION (NEED 80 PERCENT CONFIDENCE TO
ISSUE HEADLINE AND ONLY AT 30-50 PERCENT CONFIDENCE IN OCCURRENCE.
BEST CHANCE IS OVER NYC/LONG ISLAND WHERE LOW LEVELS SHOULD
SATURATE THE QUICKEST).
FOR LOWS TONIGHT AND HIGHS SUNDAY USED A BLEND OF MAV/MET
GUIDANCE WITH NAM 2-METER TEMPERATURES - ADJUSTING THE RATE OF
WARMING DOWNWARD TO ACCOUNT FOR IMPACT OF SNOW COVER. DO EXPECT
TEMPERATURES TO FALL OFF THIS EVENING - THEN LIKELY HOLD STEADY OR
EVEN RISE SLIGHTLY OVERNIGHT...THEN GRADUALLY RISE THROUGH THE DAY
ON SUNDAY. LOWS TONIGHT WILL BE NEAR NORMAL...AND HIGHS SUNDAY
AROUND 5 DEGREES ABOVE NORMAL.
ISENTROPIC LIFT AND SATURATION CONTINUES TO STRENGTHEN/DEEPEN
RESPECTIVELY SUNDAY NIGHT...AND REMAINS STRONG MONDAY MORNING.
HAVE THE POTENTIAL FOR MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL
IN THIS TIME FRAME. REFER TO HYDROLOGY SECTION FOR DETAILS ON
AMOUNTS AND POTENTIAL IMPACT.
PRECIPITATION TAPERS OFF BEHIND THE ARCTIC COLD FRONT MONDAY
AFTERNOON - AND SHARPLY COLDER AIR RUSHES IN BEHIND IT. GIVEN HOW
QUICKLY THE COLD AIR IS EXPECTED TO RUSH IN - HAVE SOME
POTENTIAL FOR A FLASH FREEZE - ESPECIALLY OVER AREAS TO THE N/W
OF NYC. ALWAYS TRICKY GAGING HOW FAST COLD AIR WORKS ITS WAY IN
OVER THE APPALACHIANS - BUT EXPECT DEPTH OF COLD AIR TO BE
SUFFICIENT THAT IT WILL MOVE IN FASTER THAN IS TYPICAL BEHIND MOST
COLD FRONTS (ABOUT A 6-12 HOUR DELAY). ALSO - GIVEN STRONG LOW
LEVEL WNW FLOW AND VERY COLD LOW LEVEL AIR WORKING IN - HAVE SOME
POTENTIAL FOR SOUND EFFECT SNOWS OVER THE EAST END OF LONG ISLAND
MONDAY NIGHT - FOR NOW JUST HAVE SLIGHT CHANCE POPS OVER THE S
FORK - BUT WILL CONTINUE TO MONITOR.
FOR LOWS SUNDAY NIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM
2-METER TEMPERATURES WITH VALUES 15-20 DEGREES ABOVE NORMAL. HIGHS
ON MONDAY WILL OCCUR DURING THE MORNING HOURS - CONSISTENT WITH A
BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES AND A MIX
DOWN FROM 900 HPA...EXCEPT 875 HPA WELL INLAND PER BUFKIT
SOUNDINGS. HIGHS SHOULD BE AROUND 5-10 DEGREES ABOVE NORMAL. USED
A BLEND OF NAM AND ECMWF 2-METER TEMPERATURES WITH
MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE FOR LOWS MONDAY NIGHT WITH VALUES
FORECAST TO BE 15 TO 20 DEGREES BELOW NORMAL. COUPLED WITH GUSTY
WNW WINDS - COULD SEE WIND CHILLS GENERALLY FROM -10 TO 0 - BUT
FROM -10 TO -20 TO THE N/W OF NYC. THERE IS ALSO A SMALL CHANCE
FOR WIND CHILLS AROUND -25 IN FAR NW ZONES - HAVE HIGHLIGHTED THIS
THREAT IN THE HWO.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
TUESDAY WILL BE BLUSTERY AND FRIGID WITH 850 TEMPERATURES OF -20
TO -24C SUPPORTING HIGHS ONLY FROM THE UPPER SINGLE DIGITS N/W OF
NYC TO THE MID TEENS ELSEWHERE - THIS IS SOME 20-30 DEGREES BELOW
NORMAL AND CONSISTENT WITH A BLEND OF MEX/MEN/EKD/ECM/ECE/WPC
GUIDANCE WITH ECMWF 2-METER TEMPERATURES. AFTERNOON WIND CHILL
READINGS SHOULD RANGE FROM -10 TO -20...EXCEPT TO AROUND 0 ACROSS
FAR E ZONES. WIND GUSTS COULD BE IN THE WIND ADVISORY RANGE DURING
THE DAY ON TUESDAY AS WELL. IN ADDITION - FLOW CONTINUES TO
SUPPORT POSSIBILITY OF SOUND EFFECT SNOWS OVER THE TWIN FORKS.
TROUGHING ALOFT LIFTS OUT OF THE NE TUESDAY NIGHT...ALLOWING FOR A
FAST WSW FLOW TO SET UP ALOFT WEDNESDAY-THURSDAY...BEFORE RIDGING
BUILDS BACK IN ON FRIDAY. FOR NOW IT APPEARS IT WILL BE DRY
TUESDAY NIGHT-WEDNESDAY NIGHT. HAVE THE POTENTIAL FOR SOME LIGHT
SNOW THURSDAY WITH WARM ADVECTION AHEAD OF A PASSING COLD
FRONT...AND ON THURSDAY NIGHT WITH A PASSING SHORTWAVE. FRIDAY
SHOULD BE DRY UNDER THE RIDGE.
FOR TEMPERATURES TUESDAY NIGHT-FRIDAY USED A BLEND OF
MEX/MEN/ECE/EKD/ECM/WPC GUIDANCE...WITH ECMWF 2-METER TEMPERATURES
MIXED IN THURSDAY-FRIDAY TO REFLECT DEEPER PENETRATION OF LOW
LEVEL COLD AIR BEHIND THE COLD FRONT THEN DEPICTED IN THE GFS.
TEMPERATURES WILL BE BELOW NORMAL THROUGH THURSDAY THEN NEAR NORMAL
ON FRIDAY. NOTE - LOWS TUESDAY NIGHT SHOULD BE AROUND 15 DEGREES
BELOW NORMAL AND HIGHS WEDNESDAY 10-15 DEGREES BELOW NORMAL.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE OVERHEAD THIS MORNING WILL SLIDE EAST THROUGH
TONIGHT.
HIGH CONFIDENCE VFR THROUGH THIS EVENING. LIGHT WINDS THIS
MORNING WILL BECOME SW 10 KT THIS AFTERNOON...THEN DIMINISH
SOMEWHAT AFTER DUSK.
A TEMPS COOL TONIGHT AND MOISTURE BEGINS TO INCREASE ON LIGHT SW
FLOW...CANNOT RULE OUT PATCHY MVFR VSBY AFTER MIDNIGHT. A WEAK
DISTURBANCE APPROACHING FROM THE SOUTH IS MORE LIKELY TO BRING
MVFR CIGS AND PATCHY FREEZING DRIZZLE TO THE NYC METRO AND COASTAL
TERMINALS IN THE PREDAWN HOURS ON SUNDAY.
.OUTLOOK FOR 12Z SUNDAY THROUGH WED...
.SUNDAY MORNING...MVFR CIGS LIKELY. PATCHY FOG AND/OR FREEZING
DRIZZLE POSSIBLE.
.SUNDAY AFTERNOON...MVFR OR LOWER CONDITIONS EXPECTED WITH
LIGHT RAIN.
.SUNDAY NIGHT-MON MORNING...IFR CONDITIONS LIKELY IN RAIN.
LLWS ALSO POSSIBLE WITH S-SW WINDS INCREASING TO 40-45 KT
AT FL015.
.MON AFTERNOON-TUE...CONDITIONS IMPROVING TO VFR. W WINDS
G25-30KT...THEN 30-35KT BY TUE AFTERNOON.
.WED...VFR. W WINDS G20KT.
&&
.MARINE...
THERE IS SOME POTENTIAL ANZ-350 COULD HAVE A FEW HOURS LATE THIS
MORNING/EARLY THIS AFTERNOON WITH SEAS BELOW 5 FT THROUGHOUT THE
ZONE. HOWEVER...THIS LULL DOES NOT APPEAR IT WILL BE LONG ENOUGH
TO ADJUST THE EXISTING SCA ANY. STILL APPEAR ON TRACK FOR SEAS TO
BUILD BACK TO 5 FT BY LATE AFTERNOON IN ANZ-350.
INCREASING SW FLOW SHOULD BUILD OCEAN SEAS BACK TO 5 FT ON MOST
IF NOT ALL OCEAN WATERS TONIGHT. STEADY SE-S FLOW 15-20 KT SHOULD
THEN MAINTAIN SCA CONDS ON THE OCEAN ESPECIALLY OUT EAST INTO MON
MORNING.
AFTER A STRONG COLD FROPA MON MORNING...WESTERLY GALES SHOULD
DEVELOP ON THE OCEAN WATERS MON AFTERNOON AND SPREAD TO ALL WATERS
MON NIGHT-TUE. THESE WINDS WILL SLOWLY DIMINISH TUE NIGHT...WITH
LINGERING SCA CONDS ON ALL WATERS WED MORNING AND ON THE EASTERN
OCEAN/SOUND/BAYS WED AFTERNOON AND POSSIBLY INTO WED NIGHT.
&&
.HYDROLOGY...
ANOTHER WIDESPREAD SIGNIFICANT PRECIP EVENT IS POSSIBLE SUNDAY
THROUGH EARLY MONDAY...MOSTLY IN THE FORM OF RAIN. THE HEAVY RAIN
COULD COMBINE WITH RESIDUAL SNOW COVER TO PRODUCE SOME MINOR
FLOODING. GENERAL ESTIMATES OF EVENT TOTAL LIQUID AMOUNTS FROM A
MODEL CONSENSUS ARE AROUND 2/3 TO 9/10 OF AN INCH.
&&
.CLIMATE...
CLIMATE RECORDS FOR JANUARY 4:
LOCATION RECORD LOW FORECAST VALUE
BRIDGEPORT...CT -1 1981 2
ISLIP...NY 10 2008 -1
LAGUARDIA...NY 4 1981 8
JFK AIRPORT...NY 8 1981 5
NYC-CENTRAL PARK...NY -3 1918 7
NEWARK...NJ 1 1981 3
&&
.EQUIPMENT...
THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS
OUT OF SERVICE.
DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY
BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER
RADIO STATION KWO35 IS OUT OF SERVICE.
DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE
INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO
DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE
WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE
INTERFERENCE ISSUE HAS BEEN RESOLVED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST MONDAY FOR ANZ350.
&&
$$
SYNOPSIS...MALOIT
NEAR TERM...MALOIT/MPS
SHORT TERM...MALOIT
LONG TERM...MALOIT
AVIATION...GOODMAN
MARINE...GOODMAN/MALOIT
HYDROLOGY...MALOIT
CLIMATE...
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
655 AM EST SAT JAN 4 2014
.SYNOPSIS...
HIGH PRESSURE WILL SLIDE EAST THROUGH TONIGHT. LOW PRESSURE MOVING
FROM THE GULF COAST STATES ON SUNDAY INTO QUEBEC BY MONDAY WILL
THEN DRAG A POTENT COLD FRONT THROUGH ON MONDAY. ARCTIC HIGH
PRESSURE WILL BUILDS IN LATER MONDAY THROUGH WEDNESDAY...THEN
SLIDE EAST WEDNESDAY NIGHT. A COLD FRONT WILL MOVE ACROSS ON
THURSDAY...FOLLOWED BY BUILDING HIGH PRESSURE ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MINOR CHANGES TO REFLECT THE LATEST TRENDS IN OBSERVATIONS AND
GUIDANCE. MAIN CHANGE WAS TO TWEAK TEMPERATURES OVER THE NEXT FEW
HOURS...MAINLY UPWARD A FEW DEGREES.
DEEP LAYERED RIDGE AXIS SLIDES TO THE EAST TODAY...WITH ASSOCIATED
SUBSIDENCE PROMOTING MINIMAL CLOUD COVER...EXCEPT OVER FAR EASTERN
ZONES WHERE WARM ADVECTION INDUCED MARINE STRATUS BEGINS TO BUILD
IN LATE IN THE AFTERNOON.
BRUTALLY COLD TO GET STARTED WITH INTERIOR ZONES AND PINE BARRENS
HAVING LOWS -10 TO -15...AND FROM 5 ABOVE TO -10 ELSEWHERE -
EXCEPT FROM 0 TO 10 ABOVE IN NYC. WILL CONTINUE WITH SPS
HIGHLIGHTING COLD TEMPERATURES EARLY. FORTUNATELY WINDS GENERALLY
LESS THAN 5 MPH - SO NO WIND CHILLS TO COMPOUND THINGS.
TEMPERATURES REBOUND TO THE MID 20S-AROUND 30 WITH DEEP LAYERED SW
FLOW SETTING UP BY AFTERNOON. HIGHS CONSISTENT WITH BLEND OF
MAV/MET GUIDANCE WITH NAM AND RUC 2-METER TEMPERATURES AND A MIX
DOWN FROM 950 HPA PER BUFKIT SOUNDINGS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
A COUPLE OF CONCERNS TONIGHT. 1ST...WITH WARM ADVECTION OVER THE
SNOW PACK - THERE IS THE POTENTIAL FOR AREAS OF FOG TO DEVELOP.
GIVEN RELATIVELY LIMITED LIQUID WATER CONTENT DO NOT EXPECT TO BE
DENSE - HOWEVER WITH TEMPERATURES BELOW FREEZING FOR ALL BUT
AROUND MONTAUK POINT - COULD SEE SOME FREEZING MIST. 2ND -
NAM/GFS/ECMWF ALL SHOW SOME DEGREE OF SATURATION ON THE 285K
ISENTROPIC SURFACE WITH WEAK TO MODERATE ISENTROPIC ASCENT - WHILE
RELATIVE DRY ALOFT. VERY OFTEN GET DRIZZLE OR LIGHT RAIN UNDER
THIS SCENARIO - SO SPOTTY -FZRA/-FZDZ IS POSSIBLE. THEN AS THE
COLUMN MOISTENS ALOFT - COULD ALSO SEE SOME -SN/-PL DEVELOP SUNDAY
MORNING UNTIL ALL PRECIPITATION TURNS TO RAIN BY MIDDAY.
FOR NOW CONFIDENCE IN EITHER IS NOT HIGH ENOUGH TO ISSUE A FREEZING
RAIN ADVISORY FOR ICE ACCRETION (NEED 80 PERCENT CONFIDENCE TO
ISSUE HEADLINE AND ONLY AT 30-50 PERCENT CONFIDENCE IN OCCURRENCE.
BEST CHANCE IS OVER NYC/LONG ISLAND WHERE LOW LEVELS SHOULD
SATURATE THE QUICKEST).
FOR LOWS TONIGHT AND HIGHS SUNDAY USED A BLEND OF MAV/MET
GUIDANCE WITH NAM 2-METER TEMPERATURES - ADJUSTING THE RATE OF
WARMING DOWNWARD TO ACCOUNT FOR IMPACT OF SNOW COVER. DO EXPECT
TEMPERATURES TO FALL OFF THIS EVENING - THEN LIKELY HOLD STEADY OR
EVEN RISE SLIGHTLY OVERNIGHT...THEN GRADUALLY RISE THROUGH THE DAY
ON SUNDAY. LOWS TONIGHT WILL BE NEAR NORMAL...AND HIGHS SUNDAY
AROUND 5 DEGREES ABOVE NORMAL.
ISENTROPIC LIFT AND SATURATION CONTINUES TO STRENGTHEN/DEEPEN
RESPECTIVELY SUNDAY NIGHT...AND REMAINS STRONG MONDAY MORNING.
HAVE THE POTENTIAL FOR MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL
IN THIS TIME FRAME. REFER TO HYDROLOGY SECTION FOR DETAILS ON
AMOUNTS AND POTENTIAL IMPACT.
PRECIPITATION TAPERS OFF BEHIND THE ARCTIC COLD FRONT MONDAY
AFTERNOON - AND SHARPLY COLDER AIR RUSHES IN BEHIND IT. GIVEN HOW
QUICKLY THE COLD AIR IS EXPECTED TO RUSH IN - HAVE SOME
POTENTIAL FOR A FLASH FREEZE - ESPECIALLY OVER AREAS TO THE N/W
OF NYC. ALWAYS TRICKY GAGING HOW FAST COLD AIR WORKS ITS WAY IN
OVER THE APPALACHIANS - BUT EXPECT DEPTH OF COLD AIR TO BE
SUFFICIENT THAT IT WILL MOVE IN FASTER THAN IS TYPICAL BEHIND MOST
COLD FRONTS (ABOUT A 6-12 HOUR DELAY). ALSO - GIVEN STRONG LOW
LEVEL WNW FLOW AND VERY COLD LOW LEVEL AIR WORKING IN - HAVE SOME
POTENTIAL FOR SOUND EFFECT SNOWS OVER THE EAST END OF LONG ISLAND
MONDAY NIGHT - FOR NOW JUST HAVE SLIGHT CHANCE POPS OVER THE S
FORK - BUT WILL CONTINUE TO MONITOR.
FOR LOWS SUNDAY NIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM
2-METER TEMPERATURES WITH VALUES 15-20 DEGREES ABOVE NORMAL. HIGHS
ON MONDAY WILL OCCUR DURING THE MORNING HOURS - CONSISTENT WITH A
BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES AND A MIX
DOWN FROM 900 HPA...EXCEPT 875 HPA WELL INLAND PER BUFKIT
SOUNDINGS. HIGHS SHOULD BE AROUND 5-10 DEGREES ABOVE NORMAL. USED
A BLEND OF NAM AND ECMWF 2-METER TEMPERATURES WITH
MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE FOR LOWS MONDAY NIGHT WITH VALUES
FORECAST TO BE 15 TO 20 DEGREES BELOW NORMAL. COUPLED WITH GUSTY
WNW WINDS - COULD SEE WIND CHILLS GENERALLY FROM -10 TO 0 - BUT
FROM -10 TO -20 TO THE N/W OF NYC. THERE IS ALSO A SMALL CHANCE
FOR WIND CHILLS AROUND -25 IN FAR NW ZONES - HAVE HIGHLIGHTED THIS
THREAT IN THE HWO.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
TUESDAY WILL BE BLUSTERY AND FRIGID WITH 850 TEMPERATURES OF -20
TO -24C SUPPORTING HIGHS ONLY FROM THE UPPER SINGLE DIGITS N/W OF
NYC TO THE MID TEENS ELSEWHERE - THIS IS SOME 20-30 DEGREES BELOW
NORMAL AND CONSISTENT WITH A BLEND OF MEX/MEN/EKD/ECM/ECE/WPC
GUIDANCE WITH ECMWF 2-METER TEMPERATURES. AFTERNOON WIND CHILL
READINGS SHOULD RANGE FROM -10 TO -20...EXCEPT TO AROUND 0 ACROSS
FAR E ZONES. WIND GUSTS COULD BE IN THE WIND ADVISORY RANGE DURING
THE DAY ON TUESDAY AS WELL. IN ADDITION - FLOW CONTINUES TO
SUPPORT POSSIBILITY OF SOUND EFFECT SNOWS OVER THE TWIN FORKS.
TROUGHING ALOFT LIFTS OUT OF THE NE TUESDAY NIGHT...ALLOWING FOR A
FAST WSW FLOW TO SET UP ALOFT WEDNESDAY-THURSDAY...BEFORE RIDGING
BUILDS BACK IN ON FRIDAY. FOR NOW IT APPEARS IT WILL BE DRY
TUESDAY NIGHT-WEDNESDAY NIGHT. HAVE THE POTENTIAL FOR SOME LIGHT
SNOW THURSDAY WITH WARM ADVECTION AHEAD OF A PASSING COLD
FRONT...AND ON THURSDAY NIGHT WITH A PASSING SHORTWAVE. FRIDAY
SHOULD BE DRY UNDER THE RIDGE.
FOR TEMPERATURES TUESDAY NIGHT-FRIDAY USED A BLEND OF
MEX/MEN/ECE/EKD/ECM/WPC GUIDANCE...WITH ECMWF 2-METER TEMPERATURES
MIXED IN THURSDAY-FRIDAY TO REFLECT DEEPER PENETRATION OF LOW
LEVEL COLD AIR BEHIND THE COLD FRONT THEN DEPICTED IN THE GFS.
TEMPERATURES WILL BE BELOW NORMAL THROUGH THURSDAY THEN NEAR NORMAL
ON FRIDAY. NOTE - LOWS TUESDAY NIGHT SHOULD BE AROUND 15 DEGREES
BELOW NORMAL AND HIGHS WEDNESDAY 10-15 DEGREES BELOW NORMAL.
&&
.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE OVERHEAD THIS MORNING WILL SLIDE EAST THROUGH
TONIGHT.
HIGH CONFIDENCE VFR THROUGH THIS EVENING. LIGHT WINDS THIS
MORNING WILL BECOME SW 10 KT THIS AFTERNOON...THEN DIMINISH
SOMEWHAT AFTER DUSK.
A TEMPS COOL TONIGHT AND MOISTURE BEGINS TO INCREASE ON LIGHT SW
FLOW...CANNOT RULE OUT PATCHY MVFR VSBY AFTER MIDNIGHT. A WEAK
DISTURBANCE APPROACHING FROM THE SOUTH IS MORE LIKELY TO BRING
MVFR CIGS AND PATCHY FREEZING DRIZZLE TO THE NYC METRO AND COASTAL
TERMINALS IN THE PREDAWN HOURS ON SUNDAY.
.OUTLOOK FOR 12Z SUNDAY THROUGH WED...
.SUNDAY MORNING...MVFR CIGS LIKELY. PATCHY FOG AND/OR FREEZING
DRIZZLE POSSIBLE.
.SUNDAY AFTERNOON...MVFR OR LOWER CONDITIONS EXPECTED WITH
LIGHT RAIN.
.SUNDAY NIGHT-MON MORNING...IFR CONDITIONS LIKELY IN RAIN.
LLWS ALSO POSSIBLE WITH S-SW WINDS INCREASING TO 40-45 KT
AT FL015.
.MON AFTERNOON-TUE...CONDITIONS IMPROVING TO VFR. W WINDS
G25-30KT...THEN 30-35KT BY TUE AFTERNOON.
.WED...VFR. W WINDS G20KT.
&&
.MARINE...
SCA ALLOWED TO EXPIRE FOR ANZ-355 AS SEAS AT 44017 AT 5.9 FT AND
WINDS CONTINUE TO DIMINISH. LEFT SCA FOR ANZ-353 AS IS FOR NOW -
THOUGH COULD END UP ENDING BEFORE SCHEDULED 9 AM END TIME.
ALSO...THERE IS SOME POTENTIAL ANZ-350 COULD HAVE A FEW HOURS
LATE THIS MORNING/EARLY THIS AFTERNOON WITH SEAS BELOW 5 FT
THROUGHOUT THE ZONE. HOWEVER...THIS LULL DOES NOT APPEAR IT WILL
BE LONG ENOUGH TO ADJUST THE EXISTING SCA ANY. STILL APPEAR ON
TRACK FOR SEAS TO BUILD BACK TO 5 FT BY LATE AFTERNOON IN ANZ-350.
INCREASING SW FLOW SHOULD BUILD OCEAN SEAS BACK TO 5 FT ON MOST
IF NOT ALL OCEAN WATERS TONIGHT. STEADY SE-S FLOW 15-20 KT SHOULD
THEN MAINTAIN SCA CONDS ON THE OCEAN ESPECIALLY OUT EAST INTO MON
MORNING.
AFTER A STRONG COLD FROPA MON MORNING...WESTERLY GALES SHOULD
DEVELOP ON THE OCEAN WATERS MON AFTERNOON AND SPREAD TO ALL WATERS
MON NIGHT-TUE. THESE WINDS WILL SLOWLY DIMINISH TUE NIGHT...WITH
LINGERING SCA CONDS ON ALL WATERS WED MORNING AND ON THE EASTERN
OCEAN/SOUND/BAYS WED AFTERNOON AND POSSIBLY INTO WED NIGHT.
&&
.HYDROLOGY...
ANOTHER WIDESPREAD SIGNIFICANT PRECIP EVENT IS POSSIBLE SUNDAY
THROUGH EARLY MONDAY...MOSTLY IN THE FORM OF RAIN. THE HEAVY RAIN
COULD COMBINE WITH RESIDUAL SNOW COVER TO PRODUCE SOME MINOR
FLOODING. GENERAL ESTIMATES OF EVENT TOTAL LIQUID AMOUNTS FROM A
MODEL CONSENSUS ARE AROUND 2/3 TO 9/10 OF AN INCH.
&&
.CLIMATE...
CLIMATE RECORDS FOR JANUARY 4:
LOCATION RECORD LOW FORECAST VALUE
BRIDGEPORT...CT -1 1981 2
ISLIP...NY 10 2008 -1
LAGUARDIA...NY 4 1981 8
JFK AIRPORT...NY 8 1981 5
NYC-CENTRAL PARK...NY -3 1918 7
NEWARK...NJ 1 1981 3
&&
.EQUIPMENT...
THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS
OUT OF SERVICE.
DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY
BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER
RADIO STATION KWO35 IS OUT OF SERVICE.
DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE
INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO
DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE
WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE
INTERFERENCE ISSUE HAS BEEN RESOLVED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST MONDAY FOR ANZ350.
SMALL CRAFT ADVISORY UNTIL 9 AM EST THIS MORNING FOR ANZ353.
&&
$$
SYNOPSIS...MALOIT
NEAR TERM...MALOIT
SHORT TERM...MALOIT
LONG TERM...MALOIT
AVIATION...GOODMAN
MARINE...MALOIT/GOODMAN
HYDROLOGY...MALOIT
AREA FORECAST DISCUSSION...CORRECTED
NWS NEW YORK NY
427 AM EST SAT JAN 4 2014
.SYNOPSIS...
HIGH PRESSURE SLIDES OFFSHORE THROUGH TONIGHT. LOW PRESSURE TRACKS
FROM THE GULF COAST STATES SUNDAY...INTO QUEBEC BY
MONDAY...DRAGGING ITS POTENT COLD FRONT THROUGH ON MONDAY. ARCTIC
HIGH PRESSURE THEN BUILDS IN THROUGH WEDNESDAY...THEN SLIDES
OFFSHORE WEDNESDAY NIGHT. A COLD FRONT CROSSES THE AREA
THURSDAY...FOLLOWED BY HIGH PRESSURE BUILDING IN ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
DEEP LAYERED RIDGE AXIS SLIDES TO THE EAST TODAY...WITH ASSOCIATED
SUBSIDENCE PROMOTING MINIMAL CLOUD COVER...EXCEPT OVER FAR EASTERN
ZONES WHERE WARM ADVECTION INDUCED MARINE STRATUS BEGINS TO BUILD
IN LATE IN THE AFTERNOON.
BRUTALLY COLD TO GET STARTED WITH INTERIOR ZONES AND PINE BARRENS
HAVING LOWS -10 TO -15...AND FROM 0 TO -10 ELSEWHERE - EXCEPT FROM
-5 TO 5 ABOVE IN NYC. WILL CONTINUE WITH SPS HIGHLIGHTING COLD
TEMPERATURES EARLY. FORTUNATELY WINDS GENERALLY LESS THAN 5 MPH -
SO NO WIND CHILLS TO COMPOUND THINGS.
TEMPERATURES REBOUND TO THE MID 20S-AROUND 30 WITH DEEP LAYERED SW
FLOW SETTING UP BY AFTERNOON. HIGHS CONSISTENT WITH BLEND OF
MAV/MET GUIDANCE WITH NAM AND RUC 2-METER TEMPERATURES AND A MIX
DOWN FROM 950 HPA PER BUFKIT SOUNDINGS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
A COUPLE OF CONCERNS TONIGHT. 1ST...WITH WARM ADVECTION OVER THE
SNOW PACK - THERE IS THE POTENTIAL FOR AREAS OF FOG TO DEVELOP.
GIVEN RELATIVELY LIMITED LIQUID WATER CONTENT DO NOT EXPECT TO BE
DENSE - HOWEVER WITH TEMPERATURES BELOW FREEZING FOR ALL BUT
AROUND MONTAUK POINT - COULD SEE SOME FREEZING MIST. 2ND -
NAM/GFS/ECMWF ALL SHOW SOME DEGREE OF SATURATION ON THE 285K
ISENTROPIC SURFACE WITH WEAK TO MODERATE ISENTROPIC ASCENT - WHILE
RELATIVE DRY ALOFT. VERY OFTEN GET DRIZZLE OR LIGHT RAIN UNDER
THIS SCENARIO - SO SPOTTY -FZRA/-ZL IS POSSIBLE. THEN AS THE
COLUMN MOISTENS ALOFT - COULD ALSO SEE SOME -SN/-PL DEVELOP SUNDAY
MORNING UNTIL ALL PRECIPITATION TURNS TO RAIN BY MIDDAY.
FOR NOW CONFIDENCE IN EITHER IS NOT HIGH ENOUGH TO ISSUE A FREEZING
RAIN ADVISORY FOR ICE ACCRETION (NEED 80 PERCENT CONFIDENCE TO
ISSUE HEADLINE AND ONLY AT 30-50 PERCENT CONFIDENCE IN OCCURRENCE.
BEST CHANCE IS OVER NYC/LONG ISLAND WHERE LOW LEVELS SHOULD
SATURATE THE QUICKEST).
FOR LOWS TONIGHT AND HIGHS SUNDAY USED A BLEND OF MAV/MET
GUIDANCE WITH NAM 2-METER TEMPERATURES - ADJUSTING THE RATE OF
WARMING DOWNWARD TO ACCOUNT FOR IMPACT OF SNOW COVER. DO EXPECT
TEMPERATURES TO FALL OFF THIS EVENING - THEN LIKELY HOLD STEADY OR
EVEN RISE SLIGHTLY OVERNIGHT...THEN GRADUALLY RISE THROUGH THE DAY
ON SUNDAY. LOWS TONIGHT WILL BE NEAR NORMAL...AND HIGHS SUNDAY
AROUND 5 DEGREES ABOVE NORMAL.
ISENTROPIC LIFT AND SATURATION CONTINUES TO STRENGTHEN/DEEPEN
RESPECTIVELY SUNDAY NIGHT...AND REMAINS STRONG MONDAY MORNING.
HAVE THE POTENTIAL FOR MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL
IN THIS TIME FRAME. REFER TO HYDROLOGY SECTION OF THE AFD FOR
DETAILS ON AMOUNTS AND POTENTIAL IMPACT.
PRECIPITATION TAPERS OFF BEHIND THE ARCTIC COLD FRONT MONDAY
AFTERNOON - AND SHARPLY COLDER AIR RUSHES IN BEHIND IT. GIVEN HOW
QUICKLY THE COLD AIR IS EXPECTED TO RUSH IN - HAVE SOME
POTENTIAL FOR A FLASH FREEZE - ESPECIALLY OVER AREAS TO THE N/W
OF NYC. ALWAYS TRICKY GAUGING HOW FAST COLD AIR WORKS ITS WAY IN
OVER THE APPALACHIANS - BUT EXPECT DEPTH OF COLD AIR TO BE
SUFFICIENT THAT IT WILL MOVE IN FASTER THAN IS TYPICAL BEHIND MOST
COLD FRONTS (ABOUT A 6-12 HOUR DELAY). ALSO - GIVEN STRONG LOW
LEVEL WNW FLOW AND VERY COLD LOW LEVEL AIR WORKING IN - HAVE SOME
POTENTIAL FOR SOUND EFFECT SNOWS OVER THE EAST END OF LONG ISLAND
MONDAY NIGHT - FOR NOW JUST HAVE SLIGHT CHANCE POPS OVER THE S
FORK - BUT WILL CONTINUE TO MONITOR.
FOR LOWS SUNDAY NIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM
2-METER TEMPERATURES WITH VALUES 15-20 DEGREES ABOVE NORMAL. HIGHS
ON MONDAY WILL OCCUR DURING THE MORNING HOURS - CONSISTENT WITH A
BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES AND A MIX
DOWN FROM 900 HPA...EXCEPT 875 HPA WELL INLAND PER BUFKIT
SOUNDINGS. HIGHS SHOULD BE AROUND 5-10 DEGREES ABOVE NORMAL. USED
A BLEND OF NAM AND ECMWF 2-METER TEMPERATURES WITH
MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE FOR LOWS MONDAY NIGHT WITH VALUES
FORECAST TO BE 15 TO 20 DEGREES BELOW NORMAL. COUPLED WITH GUSTY
WNW WINDS - COULD SEE WIND CHILLS GENERALLY FROM -10 TO 0 - BUT
FROM -10 TO -20 TO THE N/W OF NYC.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
TUESDAY WILL BE BLUSTERY AND FRIGID WITH 850 TEMPERATURES OF -20
TO -24C SUPPORTING HIGHS ONLY FROM THE UPPER SINGLE DIGITS N/W OF
NYC TO THE MID TEENS ELSEWHERE - THIS IS SOME 20-30 DEGREES BELOW
NORMAL AND CONSISTENT WITH A BLEND OF MEX/MEN/EKD/ECM/ECE/WPC
GUIDANCE WITH ECMWF 2-METER TEMPERATURES. AFTERNOON WIND CHILL
READINGS SHOULD RANGE FROM -10 TO -20...EXCEPT TO AROUND 0 ACROSS
FAR E ZONES. WIND GUSTS COULD BE IN THE WIND ADVISORY RANGE DURING
THE DAY ON TUESDAY AS WELL. IN ADDITION - FLOW CONTINUES TO
SUPPORT POSSIBILITY OF SOUND EFFECT SNOWS OVER THE TWIN FORKS.
TROUGHING ALOFT LIFTS OUT OF THE NE TUESDAY NIGHT...ALLOWING FOR A
FAST WSW FLOW TO SET UP ALOFT WEDNESDAY-THURSDAY...BEFORE RIDGING
BUILDS BACK IN ON FRIDAY. FOR NOW IT APPEARS IT WILL BE DRY
TUESDAY NIGHT-WEDNESDAY NIGHT. HAVE THE POTENTIAL FOR SOME LIGHT
SNOW THURSDAY WITH WARM ADVECTION AHEAD OF A PASSING COLD
FRONT...AND ON THURSDAY NIGHT WITH A PASSING SHORTWAVE. FRIDAY
SHOULD BE DRY UNDER THE RIDGE.
FOR TEMPERATURES TUESDAY NIGHT-FRIDAY USED A BLEND OF
MEX/MEN/ECE/EKD/ECM/WPC GUIDANCE...WITH ECMWF 2-METER TEMPERATURES
MIXED IN THURSDAY-FRIDAY TO REFLECT DEEPER PENETRATION OF LOW
LEVEL COLD AIR BEHIND THE COLD FRONT THEN DEPICTED IN THE GFS.
TEMPERATURES WILL BE BELOW NORMAL THROUGH THURSDAY THEN NEAR NORMAL
ON FRIDAY. NOTE - LOWS TUESDAY NIGHT SHOULD BE AROUND 15 DEGREES
BELOW NORMAL AND HIGHS WEDNESDAY 10-15 DEGREES BELOW NORMAL.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE WILL BUILD OVERHEAD THIS MORNING...AND THEN MOVE EAST
LATER TODAY.
VFR WITH MAINLY MID AND HIGH CLOUDS EXPECTED. LIGHT WINDS THIS
MORNING WILL BECOME SW AND INCREASE TO AROUND 10 KT THIS AFTERNOON.
.OUTLOOK FOR 06Z SUN THROUGH WED...
.LATE TONIGHT-SUNDAY MORNING...POSSIBLE MVFR OR LOWER CONDS WITH
PATCHY FOG AND FREEZING DRIZZLE.
.SUNDAY AFTERNOON...MVFR OR LOWER CONDITIONS AT TIMES IN LIGHT RAIN.
.SUNDAY NIGHT-MON MORNING...IFR CONDITIONS LIKELY IN RAIN. LLWS WITH
S WINDS 50 KT AT FL015.
.MON AFTERNOON-TUE...CONDITIONS IMPROVING TO VFR. W WINDS
G25-30KT...THEN 30-35 KT TUE AFTERNOON.
.WED...VFR. W WINDS G20KT.
&&
.MARINE...
SCA CONTINUES FOR THE OCEAN WATERS AS SEAS AT 44017 ARE STILL 6 FT
DUE TO INCOMING SE SWELL. THESE SWELLS SHOULD DROP BELOW 5 FT THIS
MORNING...BUT THEN INCREASING SW FLOW SHOULD BUILD OCEAN SEAS BACK
TO 5 FT BY LATE DAY OUT EAST...AND ON MOST IF NOT ALL OCEAN WATERS
TONIGHT. STEADY SE-S FLOW 15-20 KT SHOULD THEN MAINTAIN SCA CONDS ON
THE OCEAN ESPECIALLY OUT EAST INTO MON MORNING.
AFTER A STRONG COLD FROPA MON MORNING...WESTERLY GALES SHOULD
DEVELOP ON THE OCEAN WATERS MON AFTERNOON AND SPREAD TO ALL WATERS
MON NIGHT-TUE. THESE WINDS WILL SLOWLY DIMINISH TUE NIGHT...WITH
LINGERING SCA CONDS ON ALL WATERS WED MORNING AND ON THE EASTERN
OCEAN/SOUND/BAYS WED AFTERNOON AND POSSIBLY INTO WED NIGHT.
&&
.HYDROLOGY...
ANOTHER WIDESPREAD SIGNIFICANT PRECIP EVENT IS POSSIBLE SUNDAY
THROUGH EARLY MONDAY...MOSTLY IN THE FORM OF RAIN. THE HEAVY RAIN
COULD COMBINE WITH RESIDUAL SNOW COVER TO PRODUCE SOME MINOR
FLOODING. GENERAL ESTIMATES OF EVENT TOTAL LIQUID AMOUNTS FROM A
MODEL CONSENSUS ARE AROUND 2/3 TO 9/10 OF AN INCH.
&&
.CLIMATE...
CLIMATE RECORDS FOR JANUARY 4:
LOCATION RECORD LOW FORECAST VALUE
BRIDGEPORT...CT -1 1981 -4
ISLIP...NY 10 2008 -5
LAGUARDIA...NY 4 1981 3
JFK AIRPORT...NY 8 1981 1
NYC-CENTRAL PARK...NY -3 1918 3
NEWARK...NJ 1 1981 -1
&&
.EQUIPMENT...
THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS
OUT OF SERVICE.
DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY
BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER
RADIO STATION KWO35 IS OUT OF SERVICE.
DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE
INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO
DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE
WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE
INTERFERENCE ISSUE HAS BEEN RESOLVED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
ANZ355.
SMALL CRAFT ADVISORY UNTIL 6 AM EST MONDAY FOR ANZ350.
SMALL CRAFT ADVISORY UNTIL 9 AM EST THIS MORNING FOR ANZ353.
&&
$$
SYNOPSIS...MALOIT
NEAR TERM...MALOIT
SHORT TERM...MALOIT
LONG TERM...MALOIT
AVIATION...GOODMAN
MARINE...GOODMAN
HYDROLOGY...MALOIT
CLIMATE...
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
425 AM EST SAT JAN 4 2014
.SYNOPSIS...
HIGH PRESSURE SLIDES OFFSHORE THROUGH TONIGHT. LOW PRESSURE TRACKS
FROM THE GULF COAST STATES SUNDAY...INTO QUEBEC BY
MONDAY...DRAGGING ITS POTENT COLD FRONT THROUGH ON MONDAY. ARCTIC
HIGH PRESSURE THEN BUILDS IN THROUGH WEDNESDAY...THEN SLIDES
OFFSHORE WEDNESDAY NIGHT. A COLD FRONT CROSSES THE AREA
THURSDAY...FOLLOWED BY HIGH PRESSURE BUILDING IN ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
DEEP LAYERED RIDGE AXIS SLIDES TO THE EAST TODAY...WITH ASSOCIATED
SUBSIDENCE PROMOTING MINIMAL CLOUD COVER...EXCEPT OVER FAR EASTERN
ZONES WHERE WARM ADVECTION INDUCED MARINE STRATUS BEGINS TO BUILD
IN LATE IN THE AFTERNOON.
BRUTALLY COLD TO GET STARTED WITH INTERIOR ZONES AND PINE BARRENS
HAVING LOWS -10 TO -15...AND FROM 0 TO -10 ELSEWHERE - EXCEPT FROM
-5 TO 5 ABOVE IN NYC. WILL CONTINUE WITH SPS HIGHLIGHTING COLD
TEMPERATURES EARLY. FORTUNATELY WINDS GENERALLY LESS THAN 5 MPH -
SO NO WIND CHILLS TO COMPOUND THINGS.
TEMPERATURES REBOUND TO THE MID 20S-AROUND 30 WITH DEEP LAYERED SW
FLOW SETTING UP BY AFTERNOON. HIGHS CONSISTENT WITH BLEND OF
MAV/MET GUIDANCE WITH NAM AND RUC 2-METER TEMPERATURES AND A MIX
DOWN FROM 950 HPA PER BUFKIT SOUNDINGS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
A COUPLE OF CONCERNS TONIGHT. 1ST...WITH WARM ADVECTION OVER THE
SNOW PACK - THERE IS THE POTENTIAL FOR AREAS OF FOG TO DEVELOP.
GIVEN RELATIVELY LIMITED LIQUID WATER CONTENT DO NOT EXPECT TO BE
DENSE - HOWEVER WITH TEMPERATURES BELOW FREEZING FOR ALL BUT
AROUND MONTAUK POINT - COULD SEE SOME FREEZING MIST. 2ND -
NAM/GFS/ECMWF ALL SHOW SOME DEGREE OF SATURATION ON THE 285K
ISENTROPIC SURFACE WITH WEAK TO MODERATE ISENTROPIC ASCENT - WHILE
RELATIVE DRY ALOFT. VERY OFTEN GET DRIZZLE OR LIGHT RAIN UNDER
THIS SCENARIO - SO SPOTTY -FZRA/-ZL IS POSSIBLE. THEN AS THE
COLUMN MOISTENS ALOFT - COULD ALSO SEE SOME -SN/-PL DEVELOP SUNDAY
MORNING UNTIL ALL PRECIPITATION TURNS TO RAIN BY MIDDAY.
FOR NOW CONFIDENCE IN EITHER IS NOT HIGH ENOUGH TO ISSUE A FREEZING
RAIN ADVISORY FOR ICE ACCRETION (NEED 80 PERCENT CONFIDENCE TO
ISSUE HEADLINE AND ONLY AT 30-50 PERCENT CONFIDENCE IN OCCURRENCE.
BEST CHANCE IS OVER NYC/LONG ISLAND WHERE LOW LEVELS SHOULD
SATURATE THE QUICKEST).
FOR LOWS TONIGHT AND HIGHS SUNDAY USED A BLEND OF MAV/MET
GUIDANCE WITH NAM 2-METER TEMPERATURES - ADJUSTING THE RATE OF
WARMING DOWNWARD TO ACCOUNT FOR IMPACT OF SNOW COVER. DO EXPECT
TEMPERATURES TO FALL OFF THIS EVENING - THEN LIKELY HOLD STEADY OR
EVEN RISE SLIGHTLY OVERNIGHT...THEN GRADUALLY RISE THROUGH THE DAY
ON SUNDAY. LOWS TONIGHT WILL BE NEAR NORMAL...AND HIGHS SUNDAY
AROUND 5 DEGREES ABOVE NORMAL.
ISENTROPIC LIFT AND SATURATION CONTINUES TO STRENGTHEN/DEEPEN
RESPECTIVELY SUNDAY NIGHT...AND REMAINS STRONG MONDAY MORNING.
HAVE THE POTENTIAL FOR MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL
IN THIS TIME FRAME. REFER TO HYDROLOGY SECTION OF THE AFD FOR
DETAILS ON AMOUNTS AND POTENTIAL IMPACT.
PRECIPITATION TAPERS OFF BEHIND THE ARCTIC COLD FRONT MONDAY
AFTERNOON - AND SHARPLY COLDER AIR RUSHES IN BEHIND IT. GIVEN HOW
QUICKLY THE COLD AIR IS EXPECTED TO RUSH IN - HAVE SOME
POTENTIAL FOR A FLASH FREEZE - ESPECIALLY OVER AREAS TO THE N/W
OF NYC. ALWAYS TRICKY GAUGING HOW FAST COLD AIR WORKS ITS WAY IN
OVER THE APPALACHIANS - BUT EXPECT DEPTH OF COLD AIR TO BE
SUFFICIENT THAT IT WILL MOVE IN FASTER THAN IS TYPICAL BEHIND MOST
COLD FRONTS (ABOUT A 6-12 HOUR DELAY). ALSO - GIVEN STRONG LOW
LEVEL WNW FLOW AND VERY COLD LOW LEVEL AIR WORKING IN - HAVE SOME
POTENTIAL FOR SOUND EFFECT SNOWS OVER THE EAST END OF LONG ISLAND
MONDAY NIGHT - FOR NOW JUST HAVE SLIGHT CHANCE POPS OVER THE S
FORK - BUT WILL CONTINUE TO MONITOR.
FOR LOWS SUNDAY NIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM
2-METER TEMPERATURES WITH VALUES 15-20 DEGREES ABOVE NORMAL. HIGHS
ON MONDAY WILL OCCUR DURING THE MORNING HOURS - CONSISTENT WITH A
BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES AND A MIX
DOWN FROM 900 HPA...EXCEPT 875 HPA WELL INLAND PER BUFKIT
SOUNDINGS. HIGHS SHOULD BE AROUND 5-10 DEGREES ABOVE NORMAL. USED
A BLEND OF NAM AND ECMWF 2-METER TEMPERATURES WITH
MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE FOR LOWS MONDAY NIGHT WITH VALUES
FORECAST TO BE 15 TO 20 DEGREES BELOW NORMAL. COUPLED WITH GUSTY
WNW WINDS - COULD SEE WIND CHILLS GENERALLY FROM -10 TO 0 - BUT
FROM -10 TO -20 TO THE N/W OF NYC.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
TUESDAY WILL BE BLUSTERY AND FRIGID WITH 850 TEMPERATURES OF -20
TO -24C SUPPORTING HIGHS ONLY FROM THE UPPER SINGLE DIGITS N/W OF
NYC TO THE MID TEENS ELSEWHERE - THIS IS SOME 20-30 DEGREES BELOW
NORMAL AND CONSISTENT WITH A BLEND OF MEX/MEN/EKD/ECM/ECE/WPC
GUIDANCE WITH ECMWF 2-METER TEMPERATURES. AFTERNOON WIND CHILL
READINGS SHOULD RANGE FROM -5 TO -15...EXCEPT TO AROUND 0 ACROSS
FAR E ZONES. WIND GUSTS COULD BE IN THE WIND ADVISORY RANGE DURING
THE DAY ON TUESDAY AS WELL. IN ADDITION - FLOW CONTINUES TO
SUPPORT POSSIBILITY OF SOUND EFFECT SNOWS OVER THE TWIN FORKS.
TROUGHING ALOFT LIFTS OUT OF THE NE TUESDAY NIGHT...ALLOWING FOR A
FAST WSW FLOW TO SET UP ALOFT WEDNESDAY-THURSDAY...BEFORE RIDGING
BUILDS BACK IN ON FRIDAY. FOR NOW IT APPEARS IT WILL BE DRY
TUESDAY NIGHT-WEDNESDAY NIGHT. HAVE THE POTENTIAL FOR SOME LIGHT
SNOW THURSDAY WITH WARM ADVECTION AHEAD OF A PASSING COLD
FRONT...AND ON THURSDAY NIGHT WITH A PASSING SHORTWAVE. FRIDAY
SHOULD BE DRY UNDER THE RIDGE.
FOR TEMPERATURES TUESDAY NIGHT-FRIDAY USED A BLEND OF
MEX/MEN/ECE/EKD/ECM/WPC GUIDANCE...WITH ECMWF 2-METER TEMPERATURES
MIXED IN THURSDAY-FRIDAY TO REFLECT DEEPER PENETRATION OF LOW
LEVEL COLD AIR BEHIND THE COLD FRONT THEN DEPICTED IN THE GFS.
TEMPERATURES WILL BE BELOW NORMAL THROUGH THURSDAY THEN NEAR NORMAL
ON FRIDAY. NOTE - LOWS TUESDAY NIGHT SHOULD BE AROUND 15 DEGREES
BELOW NORMAL AND HIGHS WEDNESDAY 10-15 DEGREES BELOW NORMAL.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE WILL BUILD OVERHEAD THIS MORNING...AND THEN MOVE EAST
LATER TODAY.
VFR WITH MAINLY MID AND HIGH CLOUDS EXPECTED. LIGHT WINDS THIS
MORNING WILL BECOME SW AND INCREASE TO AROUND 10 KT THIS AFTERNOON.
.OUTLOOK FOR 06Z SUN THROUGH WED...
.LATE TONIGHT-SUNDAY MORNING...POSSIBLE MVFR OR LOWER CONDS WITH
PATCHY FOG AND FREEZING DRIZZLE.
.SUNDAY AFTERNOON...MVFR OR LOWER CONDITIONS AT TIMES IN LIGHT RAIN.
.SUNDAY NIGHT-MON MORNING...IFR CONDITIONS LIKELY IN RAIN. LLWS WITH
S WINDS 50 KT AT FL015.
.MON AFTERNOON-TUE...CONDITIONS IMPROVING TO VFR. W WINDS
G25-30KT...THEN 30-35 KT TUE AFTERNOON.
.WED...VFR. W WINDS G20KT.
&&
.MARINE...
SCA CONTINUES FOR THE OCEAN WATERS AS SEAS AT 44017 ARE STILL 6 FT
DUE TO INCOMING SE SWELL. THESE SWELLS SHOULD DROP BELOW 5 FT THIS
MORNING...BUT THEN INCREASING SW FLOW SHOULD BUILD OCEAN SEAS BACK
TO 5 FT BY LATE DAY OUT EAST...AND ON MOST IF NOT ALL OCEAN WATERS
TONIGHT. STEADY SE-S FLOW 15-20 KT SHOULD THEN MAINTAIN SCA CONDS ON
THE OCEAN ESPECIALLY OUT EAST INTO MON MORNING.
AFTER A STRONG COLD FROPA MON MORNING...WESTERLY GALES SHOULD
DEVELOP ON THE OCEAN WATERS MON AFTERNOON AND SPREAD TO ALL WATERS
MON NIGHT-TUE. THESE WINDS WILL SLOWLY DIMINISH TUE NIGHT...WITH
LINGERING SCA CONDS ON ALL WATERS WED MORNING AND ON THE EASTERN
OCEAN/SOUND/BAYS WED AFTERNOON AND POSSIBLY INTO WED NIGHT.
&&
.HYDROLOGY...
ANOTHER WIDESPREAD SIGNIFICANT PRECIP EVENT IS POSSIBLE SUNDAY
THROUGH EARLY MONDAY...MOSTLY IN THE FORM OF RAIN. THE HEAVY RAIN
COULD COMBINE WITH RESIDUAL SNOW COVER TO PRODUCE SOME MINOR
FLOODING. GENERAL ESTIMATES OF EVENT TOTAL LIQUID AMOUNTS FROM A
MODEL CONSENSUS ARE AROUND 2/3 TO 9/10 OF AN INCH.
&&
.CLIMATE...
CLIMATE RECORDS FOR JANUARY 4:
LOCATION RECORD LOW FORECAST VALUE
BRIDGEPORT...CT -1 1981 -4
ISLIP...NY 10 2008 -5
LAGUARDIA...NY 4 1981 3
JFK AIRPORT...NY 8 1981 1
NYC-CENTRAL PARK...NY -3 1918 3
NEWARK...NJ 1 1981 -1
&&
.EQUIPMENT...
THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS
OUT OF SERVICE.
DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY
BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER
RADIO STATION KWO35 IS OUT OF SERVICE.
DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE
INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO
DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE
WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE
INTERFERENCE ISSUE HAS BEEN RESOLVED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
ANZ355.
SMALL CRAFT ADVISORY UNTIL 6 AM EST MONDAY FOR ANZ350.
SMALL CRAFT ADVISORY UNTIL 9 AM EST THIS MORNING FOR ANZ353.
&&
$$
SYNOPSIS...MALOIT
NEAR TERM...MALOIT
SHORT TERM...MALOIT
LONG TERM...MALOIT
AVIATION...GOODMAN
MARINE...GOODMAN
HYDROLOGY...MALOIT
CLIMATE...
EQUIPMENT...
AREA FORECAST DISCUSSION...UPDATED
NWS COLUMBIA SC
1020 PM EST SUN JAN 5 2014
.SYNOPSIS...
DEEP LOW PRESSURE CONTINUES TRACKING THROUGH THE OHIO VALLEY WITH
THE COLDEST AIR OF THE SEASON ENVELOPING MUCH OF THE CENTRAL US.
THIS WILL PUSH A STRONG COLD FRONT THROUGH THE AREA LATE TONIGHT
INTO EARLY MONDAY. BEHIND THE FRONT TEMPERATURES WILL QUICKLY DROP
BELOW FREEZING FROM MONDAY EVENING INTO MIDDAY WEDNESDAY AS DRY
ARCTIC HIGH PRESSURE BUILDS IN.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
9PM ANALYSIS SHOWS DEEPENING SURFACE LOW PRESSURE LIFTING THROUGH
OHIO WHILE THE POLAR ARCTIC COLD FRONT PUSHES STEADILY ACROSS THE
TENNESSEE VALLEY AND HAS MADE IT THROUGH BIRMINGHAM. A WARM FRONT
WAS ALSO SITUATED JUST TO OUR SOUTH AND STRENGTHENING LOW LEVEL
FLOW AHEAD OF THE APPROACHING FRONT ASSOCIATED WITH THE LARGE
UPPER TROUGH MOVING THROUGH THE MISSISSIPPI VALLEY HAS RESULTED IN
INCREASED RAIN SHOWERS OVER THE FORECAST AREA THIS EVENING. HAVE
INCREASED POPS TO LIKELY IN THE WESTERN PART OF THE FORECAST AREA
LATE EVENING THROUGH OVERNIGHT WITH HIGHER CHANCE POPS CENTRAL AND
EAST LATER TONIGHT. TEMPERATURES WILL HOLD STEADY OR SLOWLY RISE
OVERNIGHT WITH WARM ADVECTION TAKING PLACE AND INCREASING SURFACE
WINDS AND MIXING. THE FRONT SHOULD REACH THE FORECAST AREA BETWEEN
10Z-12Z. EXPECT QPF AMOUNTS TO GENERALLY BE LIGHT WITH
PRECIPITABLE WATER VALUES AROUND AN INCH.
DENSE FOG HAS LIFTED IN THE WESTERN MIDLANDS AS LOW LEVEL FLOW
INCREASES AND MIXING IS INCREASING AS VISIBILITIES HAVE IMPROVED.
THEREFORE HAVE CANCELLED THE DENSE FOG ADVISORY. LAKE WIND
ADVISORY STILL ON TRACK TAKE EFFECT JUST BEHIND THE FRONTAL
PASSAGE EARLY MONDAY MORNING.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
MONDAY AND MONDAY NIGHT...COLD FRONT WILL MOVE OFFSHORE DURING THE
MORNING WITH TEMPERATURES FALLING FROM THE LATE MORNING THROUGH
THE AFTERNOON HOURS AS COLD AND DRY ARCTIC HIGH PRESSURE BUILDS
IN. SEVERAL CONCERNS FOR MONDAY AND MONDAY NIGHT WITH THE FIRST
BEING ROAD CONDITIONS. THIS WILL BE SHORT LIVED CONCERN AS PRECIP
EARLY MONDAY WILL BE LIQUID...AND WITH ROAD TEMPERATURES WELL
ABOVE FREEZING AND GUSTY WINDS ROADS WILL QUICKLY DRY BY THE LATE
MORNING HOURS RESULTING IN NO CHANCE FOR ICING OF THE ROADWAYS.
NEXT IS THE WINDS...WHICH WILL CONTINUE STRONG AND GUSTY THROUGH
THE DAY WITH SUSTAINED WINDS OF 15 TO 20 MPH WITH GUSTS TO 30 MPH.
AS SUCH HAVE ISSUED A LAKE WIND ADVISORY BEGINNING AT 7 AM AND
RUNNING THROUGH TUESDAY MORNING AT 7 AM. FINAL CONCERN WILL BE LOW
TEMPERATURES MONDAY NIGHT AND WIND CHILL TEMPERATURES. EXPECT LOWS
MONDAY NIGHT IN THE LOWER TEENS AND ALTHOUGH WINDS WILL BE
SUBSIDING TOWARD DAYBREAK WIND CHILL READINGS WILL BE AROUND ZERO
FOR SEVERAL HOURS. THIS BRINGS ABOUT THE POTENTIAL FOR A WIND
CHILL ADVISORY...HOWEVER CONFIDENCE CURRENTLY NOT HIGH ENOUGH TO
ISSUE AND WILL CONTINUE TO MONITOR.
TUESDAY AND TUESDAY NIGHT...HIGH PRESSURE WILL BECOME CENTERED
OVER THE REGION FOR TUESDAY AFTERNOON AND NIGHT WITH TEMPERATURES
REMAINING THE FOCUS OF THE FORECAST. WITH THE ARCTIC HIGH
BLANKETING THE REGION WITH COLD AIR ADVECTION TEMPERATURES WILL
STRUGGLE TO REACH THE FREEZING MARK TUESDAY AFTERNOON...EVEN UNDER
FULL SUNSHINE. WITH THE PRESSURE GRADIENT RELAXING AS THE HIGH
CENTERS OVER THE REGION WINDS WILL SUBSIDE THROUGH THE DAY AND
BECOME LIGHT AND VARIABLE DURING THE EVENING. THIS WILL ALLOW FOR
A NIGHT OF EXCELLENT RADIATIONAL COOLING WITH TEMPERATURES AGAIN
PLUNGING INTO THE MID 30S FOR MOST LOCATIONS...AND SLIGHTLY COOLER
IN OUTLYING LOCATIONS.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
MODELS ARE IN GOOD AGREEMENT THROUGH THE LONG TERM WITH THE
PATTERN REMAINING ACTIVE THROUGH SUNDAY. THIS WILL KEEP THE ARCTIC
HIGH PRESSURE OVER THE REGION THROUGH WEDNESDAY NIGHT WITH A
SERIES OF WEAK DISTURBANCES CROSSING THE REGION THURSDAY AFTERNOON
THROUGH THE WEEKEND. TEMPERATURES WILL BEGIN TO MODERATE DURING
THE LATTER HALF OF THE WEEK WHICH WILL ENSURE ALL PRECIPITATION
EXPECTED WILL FALL AS RAIN. TEMPERATURES WILL BE BELOW NORMAL TO
START THE LONG TERM THEN WARM TO ABOVE NORMAL FOR SATURDAY AND
SUNDAY.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
HIGH LOW-LEVEL MOISTURE IS TRAPPED BELOW A STRONG INVERSION. SOME
IMPROVEMENT IN CEILINGS AND VISIBILITIES HAS OCCURRED AT SOME OF THE
TERMINALS BUT THIS MAY BE TEMPORARY BECAUSE OF THE LOW-LEVEL
MOISTURE. USED THE HRRR AND FORECASTED IFR CONDITIONS BECOMING
WIDESPREAD OVERNIGHT. HOWEVER...INCREASED MIXING AHEAD OF THE STRONG
COLD FRONT SHOULD CAUSE IMPROVING CEILINGS TOWARD 12Z. UNTIL THE
STRONGER MIXING OCCURS THE LATEST KCAE 88D AND NAM SUPPORT
SIGNIFICANT LLWS. SCATTERED SHOWERS WILL OCCUR IN THE WARM ADVECTION
PATTERN AHEAD OF THE STRONG COLD FRONT AND THESE SHOWERS MAY AFFECT
THE TERMINALS. DRYING WILL OCCUR BEHIND THE FRONT BUT IT WILL BE
WINDY. THE GFS LAMP SUPPORTED GUSTS NEAR 28 KNOTS.
EXTENDED AVIATION OUTLOOK...WIND GUSTS NEAR 28 KNOTS WILL OCCUR
TUESDAY NIGHT BEHIND THE STRONG COLD FRONT. MOISTURE IN AN ONSHORE
FLOW MAY RESULT IN RESTRICTIONS BEGINNING LATE WEDNESDAY NIGHT AND
CONTINUING THROUGH FRIDAY.
&&
.CLIMATE...
THE ARCTIC HIGH PRESSURE AIR MASS THAT WILL BUILD INTO OUR REGION
MONDAY THROUGH WEDNESDAY IS EXPECTED TO PROVIDE THE POTENTIAL FOR
DAILY RECORD LOW TEMPERATURES...AND PERHAPS THE LOWEST TEMPERATURES
SEEN IN QUITE A WHILE. THE LOWEST TEMPERATURES ARE EXPECTED TO OCCUR
TUESDAY AND WEDNESDAY...JANUARY 7TH AND 8TH.
DAILY RECORD LOW MIN TEMPS FOR TUE JAN 7...
COLUMBIA SC (CAE)...16 (1924)
AUGUSTA GA (AGS)...15 (1970)
DAILY RECORD LOW MAX TEMPS FOR TUE JAN 7...
CAE...31 (1988)
AGS...30 (1884)
DAILY RECORD LOW MIN TEMPS FOR WED JAN 8...
CAE...12 (1970)
AGS...9 (1970).
IF A LOW TEMPERATURE LOWER THAN 13 OCCURS AT CAE...IT WILL BE THE
LOWEST TEMPERATURE AT CAE SINCE JAN 28 1986...WHEN THE LOW WAS 9
DEGREES.
IF A LOW TEMPERATURE LOWER THAN 10 OCCURS AT AGS...IT WILL BE THE
LOWEST TEMP AT AGS SINCE JAN 20 1985...WHEN THE LOW WAS 8.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...LAKE WIND ADVISORY FROM 7 AM MONDAY TO 7 AM EST TUESDAY FOR
SCZ015-016-018-020>022-025>031-035>038-041.
GA...LAKE WIND ADVISORY FROM 7 AM MONDAY TO 7 AM EST TUESDAY FOR
GAZ040-063>065-077.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
957 PM EST SUN JAN 5 2014
.SYNOPSIS...
DEEP LOW PRESSURE CONTINUES TRACKING THROUGH THE OHIO VALLEY WITH
THE COLDEST AIR OF THE SEASON ENVELOPING MUCH OF THE CENTRAL US.
THIS WILL PUSH A STRONG COLD FRONT THROUGH THE AREA LATE TONIGHT
INTO EARLY MONDAY. BEHIND THE FRONT TEMPERATURES WILL QUICKLY DROP
BELOW FREEZING FROM MONDAY EVENING INTO MIDDAY WEDNESDAY AS DRY
ARCTIC HIGH PRESSURE BUILDS IN.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
9PM ANALYSIS SHOWS DEEPENING SURFACE LOW PRESSURE LIFTING THROUGH
OHIO WHILE THE POLAR ARCTIC COLD FRONT PUSHES STEADILY ACROSS THE
TENNESSEE VALLEY AND HAS MADE IT THROUGH BIRMINGHAM. A WARM FRONT
WAS ALSO SITUATED JUST TO OUR SOUTH AND STRENGTHENING LOW LEVEL
FLOW AHEAD OF THE APPROACHING FRONT ASSOCIATED WITH THE LARGE
UPPER TROUGH MOVING THROUGH THE MISSISSIPPI VALLEY HAS RESULTED IN
INCREASED RAIN SHOWERS OVER THE FORECAST AREA THIS EVENING. HAVE
INCREASED POPS TO LIKELY IN THE WESTERN PART OF THE FORECAST AREA
LATE EVENING THROUGH OVERNIGHT WITH HIGHER CHANCE POPS CENTRAL AND
EAST LATER TONIGHT. TEMPERATURES WILL HOLD STEADY OR SLOWLY RISE
OVERNIGHT WITH WARM ADVECTION TAKING PLACE AND INCREASING SURFACE
WINDS AND MIXING. THE FRONT SHOULD REACH THE FORECAST AREA BETWEEN
10Z-12Z. EXPECT QPF AMOUNTS TO GENERALLY BE LIGHT WITH
PRECIPITABLE WATER VALUES AROUND AN INCH.
DENSE FOG CONTINUES IN THE FAR NORTHWESTERN MIDLANDS THIS EVENING
AND A DENSE FOG ADVISORY REMAINS IN EFFECT FOR THAT AREA THROUGH
4AM. LAKE WIND ADVISORY STILL ON TRACK TAKE EFFECT JUST BEHIND THE
FRONTAL PASSAGE EARLY TOMORROW MORNING.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
MONDAY AND MONDAY NIGHT...COLD FRONT WILL MOVE OFFSHORE DURING THE
MORNING WITH TEMPERATURES FALLING FROM THE LATE MORNING THROUGH
THE AFTERNOON HOURS AS COLD AND DRY ARCTIC HIGH PRESSURE BUILDS
IN. SEVERAL CONCERNS FOR MONDAY AND MONDAY NIGHT WITH THE FIRST
BEING ROAD CONDITIONS. THIS WILL BE SHORT LIVED CONCERN AS PRECIP
EARLY MONDAY WILL BE LIQUID...AND WITH ROAD TEMPERATURES WELL
ABOVE FREEZING AND GUSTY WINDS ROADS WILL QUICKLY DRY BY THE LATE
MORNING HOURS RESULTING IN NO CHANCE FOR ICING OF THE ROADWAYS.
NEXT IS THE WINDS...WHICH WILL CONTINUE STRONG AND GUSTY THROUGH
THE DAY WITH SUSTAINED WINDS OF 15 TO 20 MPH WITH GUSTS TO 30 MPH.
AS SUCH HAVE ISSUED A LAKE WIND ADVISORY BEGINNING AT 7 AM AND
RUNNING THROUGH TUESDAY MORNING AT 7 AM. FINAL CONCERN WILL BE LOW
TEMPERATURES MONDAY NIGHT AND WIND CHILL TEMPERATURES. EXPECT LOWS
MONDAY NIGHT IN THE LOWER TEENS AND ALTHOUGH WINDS WILL BE
SUBSIDING TOWARD DAYBREAK WIND CHILL READINGS WILL BE AROUND ZERO
FOR SEVERAL HOURS. THIS BRINGS ABOUT THE POTENTIAL FOR A WIND
CHILL ADVISORY...HOWEVER CONFIDENCE CURRENTLY NOT HIGH ENOUGH TO
ISSUE AND WILL CONTINUE TO MONITOR.
TUESDAY AND TUESDAY NIGHT...HIGH PRESSURE WILL BECOME CENTERED
OVER THE REGION FOR TUESDAY AFTERNOON AND NIGHT WITH TEMPERATURES
REMAINING THE FOCUS OF THE FORECAST. WITH THE ARCTIC HIGH
BLANKETING THE REGION WITH COLD AIR ADVECTION TEMPERATURES WILL
STRUGGLE TO REACH THE FREEZING MARK TUESDAY AFTERNOON...EVEN UNDER
FULL SUNSHINE. WITH THE PRESSURE GRADIENT RELAXING AS THE HIGH
CENTERS OVER THE REGION WINDS WILL SUBSIDE THROUGH THE DAY AND
BECOME LIGHT AND VARIABLE DURING THE EVENING. THIS WILL ALLOW FOR
A NIGHT OF EXCELLENT RADIATIONAL COOLING WITH TEMPERATURES AGAIN
PLUNGING INTO THE MID 30S FOR MOST LOCATIONS...AND SLIGHTLY COOLER
IN OUTLYING LOCATIONS.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
MODELS ARE IN GOOD AGREEMENT THROUGH THE LONG TERM WITH THE
PATTERN REMAINING ACTIVE THROUGH SUNDAY. THIS WILL KEEP THE ARCTIC
HIGH PRESSURE OVER THE REGION THROUGH WEDNESDAY NIGHT WITH A
SERIES OF WEAK DISTURBANCES CROSSING THE REGION THURSDAY AFTERNOON
THROUGH THE WEEKEND. TEMPERATURES WILL BEGIN TO MODERATE DURING
THE LATTER HALF OF THE WEEK WHICH WILL ENSURE ALL PRECIPITATION
EXPECTED WILL FALL AS RAIN. TEMPERATURES WILL BE BELOW NORMAL TO
START THE LONG TERM THEN WARM TO ABOVE NORMAL FOR SATURDAY AND
SUNDAY.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
HIGH LOW-LEVEL MOISTURE IS TRAPPED BELOW A STRONG INVERSION. SOME
IMPROVEMENT IN CEILINGS AND VISIBILITIES HAS OCCURRED AT SOME OF THE
TERMINALS BUT THIS MAY BE TEMPORARY BECAUSE OF THE LOW-LEVEL
MOISTURE. USED THE HRRR AND FORECASTED IFR CONDITIONS BECOMING
WIDESPREAD OVERNIGHT. HOWEVER...INCREASED MIXING AHEAD OF THE STRONG
COLD FRONT SHOULD CAUSE IMPROVING CEILINGS TOWARD 12Z. UNTIL THE
STRONGER MIXING OCCURS THE LATEST KCAE 88D AND NAM SUPPORT
SIGNIFICANT LLWS. SCATTERED SHOWERS WILL OCCUR IN THE WARM ADVECTION
PATTERN AHEAD OF THE STRONG COLD FRONT AND THESE SHOWERS MAY AFFECT
THE TERMINALS. DRYING WILL OCCUR BEHIND THE FRONT BUT IT WILL BE
WINDY. THE GFS LAMP SUPPORTED GUSTS NEAR 28 KNOTS.
EXTENDED AVIATION OUTLOOK...WIND GUSTS NEAR 28 KNOTS WILL OCCUR
TUESDAY NIGHT BEHIND THE STRONG COLD FRONT. MOISTURE IN AN ONSHORE
FLOW MAY RESULT IN RESTRICTIONS BEGINNING LATE WEDNESDAY NIGHT AND
CONTINUING THROUGH FRIDAY.
&&
.CLIMATE...
THE ARCTIC HIGH PRESSURE AIR MASS THAT WILL BUILD INTO OUR REGION
MONDAY THROUGH WEDNESDAY IS EXPECTED TO PROVIDE THE POTENTIAL FOR
DAILY RECORD LOW TEMPERATURES...AND PERHAPS THE LOWEST TEMPERATURES
SEEN IN QUITE A WHILE. THE LOWEST TEMPERATURES ARE EXPECTED TO OCCUR
TUESDAY AND WEDNESDAY...JANUARY 7TH AND 8TH.
DAILY RECORD LOW MIN TEMPS FOR TUE JAN 7...
COLUMBIA SC (CAE)...16 (1924)
AUGUSTA GA (AGS)...15 (1970)
DAILY RECORD LOW MAX TEMPS FOR TUE JAN 7...
CAE...31 (1988)
AGS...30 (1884)
DAILY RECORD LOW MIN TEMPS FOR WED JAN 8...
CAE...12 (1970)
AGS...9 (1970).
IF A LOW TEMPERATURE LOWER THAN 13 OCCURS AT CAE...IT WILL BE THE
LOWEST TEMPERATURE AT CAE SINCE JAN 28 1986...WHEN THE LOW WAS 9
DEGREES.
IF A LOW TEMPERATURE LOWER THAN 10 OCCURS AT AGS...IT WILL BE THE
LOWEST TEMP AT AGS SINCE JAN 20 1985...WHEN THE LOW WAS 8.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...LAKE WIND ADVISORY FROM 7 AM MONDAY TO 7 AM EST TUESDAY FOR
SCZ015-016-018-020>022-025>031-035>038-041.
DENSE FOG ADVISORY UNTIL 4 AM EST MONDAY FOR SCZ015-020-021-
026.
GA...LAKE WIND ADVISORY FROM 7 AM MONDAY TO 7 AM EST TUESDAY FOR
GAZ040-063>065-077.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
625 PM EST SUN JAN 5 2014
.SYNOPSIS...
DEEP LOW PRESSURE CONTINUES TRACKING TOWARD THE OHIO VALLEY WITH THE
COLDEST AIR OF THE SEASON ENVELOPING MUCH OF THE CENTRAL US. THIS
WILL PUSH A STRONG COLD FRONT THROUGH THE AREA LATE TONIGHT INTO
EARLY MONDAY. BEHIND THE FRONT TEMPERATURES WILL QUICKLY DROP
BELOW FREEZING FROM MONDAY EVENING INTO MIDDAY WEDNESDAY AS DRY
ARCTIC HIGH PRESSURE BUILDS IN.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
THE MAIN ARCTIC COLD FRONT WILL STILL BE OFF TO THE WEST OF THE
CWA THROUGH MUCH OF THE OVERNIGHT HOURS...BUT WILL BE POISED TO
PUSH INTO THE WESTERN COUNTIES TOWARDS THE MORNING HOURS ON
MONDAY. AHEAD OF THIS FRONT...AREAS OF DENSE FOG WILL BE FOUND
ACROSS THE NORTHERN CWA. SHOULD BECOME RATHER GUSTY TOWARDS THE
MORNING. THERE WILL BE AT LEAST A CHANCE OF SOME RAINFALL THROUGH
THE OVERNIGHT HOURS...WITH THE BEST CHANCES PROBABLY NOT UNTIL
AFTER MIDNIGHT. TEMPERATURES WILL FALL SLIGHTLY THIS EVENING...
THEN READINGS SHOULD EITHER REMAIN STEADY OR SLOWLY RISE AHEAD OF
THE FRONT. EXPECT TEMPS TO HAVE RISEN BACK INTO THE 50S OVER MOST
AREAS AFTER MIDNIGHT. ENJOY THIS WHILE IT LASTS BECAUSE BIG
CHANGES WILL BE IN STORE AROUND SUNRISE ACROSS THE WESTERN
COUNTIES AS THE MAIN FRONT BEGINS TO ENTER THE AREA.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
MONDAY AND MONDAY NIGHT...COLD FRONT WILL MOVE OFFSHORE DURING THE
MORNING WITH TEMPERATURES FALLING FROM THE LATE MORNING THROUGH
THE AFTERNOON HOURS AS COLD AND DRY ARCTIC HIGH PRESSURE BUILDS
IN. SEVERAL CONCERNS FOR MONDAY AND MONDAY NIGHT WITH THE FIRST
BEING ROAD CONDITIONS. THIS WILL BE SHORT LIVED CONCERN AS PRECIP
EARLY MONDAY WILL BE LIQUID...AND WITH ROAD TEMPERATURES WELL
ABOVE FREEZING AND GUSTY WINDS ROADS WILL QUICKLY DRY BY THE LATE
MORNING HOURS RESULTING IN NO CHANCE FOR ICING OF THE ROADWAYS.
NEXT IS THE WINDS...WHICH WILL CONTINUE STRONG AND GUSTY THROUGH
THE DAY WITH SUSTAINED WINDS OF 15 TO 20 MPH WITH GUSTS TO 30 MPH.
AS SUCH HAVE ISSUED A LAKE WIND ADVISORY BEGINNING AT 7 AM AND
RUNNING THROUGH TUESDAY MORNING AT 7 AM. FINAL CONCERN WILL BE LOW
TEMPERATURES MONDAY NIGHT AND WIND CHILL TEMPERATURES. EXPECT LOWS
MONDAY NIGHT IN THE LOWER TEENS AND ALTHOUGH WINDS WILL BE
SUBSIDING TOWARD DAYBREAK WIND CHILL READINGS WILL BE AROUND ZERO
FOR SEVERAL HOURS. THIS BRINGS ABOUT THE POTENTIAL FOR A WIND
CHILL ADVISORY...HOWEVER CONFIDENCE CURRENTLY NOT HIGH ENOUGH TO
ISSUE AND WILL CONTINUE TO MONITOR.
TUESDAY AND TUESDAY NIGHT...HIGH PRESSURE WILL BECOME CENTERED
OVER THE REGION FOR TUESDAY AFTERNOON AND NIGHT WITH TEMPERATURES
REMAINING THE FOCUS OF THE FORECAST. WITH THE ARCTIC HIGH
BLANKETING THE REGION WITH COLD AIR ADVECTION TEMPERATURES WILL
STRUGGLE TO REACH THE FREEZING MARK TUESDAY AFTERNOON...EVEN UNDER
FULL SUNSHINE. WITH THE PRESSURE GRADIENT RELAXING AS THE HIGH
CENTERS OVER THE REGION WINDS WILL SUBSIDE THROUGH THE DAY AND
BECOME LIGHT AND VARIABLE DURING THE EVENING. THIS WILL ALLOW FOR
A NIGHT OF EXCELLENT RADIATIONAL COOLING WITH TEMPERATURES AGAIN
PLUNGING INTO THE MID 30S FOR MOST LOCATIONS...AND SLIGHTLY COOLER
IN OUTLYING LOCATIONS.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
MODELS ARE IN GOOD AGREEMENT THROUGH THE LONG TERM WITH THE
PATTERN REMAINING ACTIVE THROUGH SUNDAY. THIS WILL KEEP THE ARCTIC
HIGH PRESSURE OVER THE REGION THROUGH WEDNESDAY NIGHT WITH A
SERIES OF WEAK DISTURBANCES CROSSING THE REGION THURSDAY AFTERNOON
THROUGH THE WEEKEND. TEMPERATURES WILL BEGIN TO MODERATE DURING
THE LATTER HALF OF THE WEEK WHICH WILL ENSURE ALL PRECIPITATION
EXPECTED WILL FALL AS RAIN. TEMPERATURES WILL BE BELOW NORMAL TO
START THE LONG TERM THEN WARM TO ABOVE NORMAL FOR SATURDAY AND
SUNDAY.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
HIGH LOW-LEVEL MOISTURE IS TRAPPED BELOW A STRONG INVERSION. SOME
IMPROVEMENT IN CEILINGS AND VISIBILITIES HAS OCCURRED AT SOME OF THE
TERMINALS BUT THIS MAY BE TEMPORARY BECAUSE OF THE LOW-LEVEL
MOISTURE. USED THE HRRR AND FORECASTED IFR OR LOW-END MVFR
CONDITIONS BECOMING WIDESPREAD AROUND 05Z. INCREASED MIXING AHEAD OF
THE STRONG COLD FRONT SHOULD CAUSE IMPROVING CEILINGS TOWARD 12Z.
UNTIL THE STRONGER MIXING OCCURS THE LATEST KCAE 88D AND NAM SUPPORT
SIGNIFICANT LLWS. SCATTERED SHOWERS WILL OCCUR IN THE WARM ADVECTION
PATTERN AHEAD OF THE STRONG COLD FRONT. THE SHOWER CHANCE IS TOO
LOW TO INCLUDE IN THE TERMINAL FORECASTS AT THIS TIME. DRYING WILL
OCCUR BEHIND THE FRONT BUT IT WILL BE WINDY. THE GFS LAMP SUPPORTED
GUSTS NEAR 28 KNOTS.
EXTENDED AVIATION OUTLOOK...WIND GUSTS NEAR 28 KNOTS WILL OCCUR
TUESDAY NIGHT BEHIND THE STRONG COLD FRONT. MOISTURE IN AN ONSHORE
FLOW MAY RESULT IN RESTRICTIONS BEGINNING LATE WEDNESDAY NIGHT AND
CONTINUING THROUGH FRIDAY.
&&
.CLIMATE...
THE ARCTIC HIGH PRESSURE AIR MASS THAT WILL BUILD INTO OUR REGION
MONDAY THROUGH WEDNESDAY IS EXPECTED TO PROVIDE THE POTENTIAL FOR
DAILY RECORD LOW TEMPERATURES...AND PERHAPS THE LOWEST TEMPERATURES
SEEN IN QUITE A WHILE. THE LOWEST TEMPERATURES ARE EXPECTED TO OCCUR
TUESDAY AND WEDNESDAY...JANUARY 7TH AND 8TH.
DAILY RECORD LOW MIN TEMPS FOR TUE JAN 7...
COLUMBIA SC (CAE)...16 (1924)
AUGUSTA GA (AGS)...15 (1970)
DAILY RECORD LOW MAX TEMPS FOR TUE JAN 7...
CAE...31 (1988)
AGS...30 (1884)
DAILY RECORD LOW MIN TEMPS FOR WED JAN 8...
CAE...12 (1970)
AGS...9 (1970).
IF A LOW TEMPERATURE LOWER THAN 13 OCCURS AT CAE...IT WILL BE THE
LOWEST TEMPERATURE AT CAE SINCE JAN 28 1986...WHEN THE LOW WAS 9
DEGREES.
IF A LOW TEMPERATURE LOWER THAN 10 OCCURS AT AGS...IT WILL BE THE
LOWEST TEMP AT AGS SINCE JAN 20 1985...WHEN THE LOW WAS 8.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...LAKE WIND ADVISORY FROM 7 AM MONDAY TO 7 AM EST TUESDAY FOR
SCZ015-016-018-020>022-025>031-035>038-041.
DENSE FOG ADVISORY UNTIL 4 AM EST MONDAY FOR SCZ015-020-021-
026.
GA...LAKE WIND ADVISORY FROM 7 AM MONDAY TO 7 AM EST TUESDAY FOR
GAZ040-063>065-077.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
821 PM EST SUN JAN 5 2014
.SYNOPSIS...
ISSUED AT 520 AM EST SUN JAN 5 2014
A STRONG SYSTEM WILL BRING HEAVY SNOW TO THE AREA TODAY AND INTO
THIS EVENING. AMOUNTS OF 8 TO 16 INCHES ARE POSSIBLE. A WINTER
STORM WARNING IS IN EFFECT THROUGH THIS EVENING. EXTREMELY COLD
ARCTIC AIR WILL MOVE IN BEHIND THE SYSTEM THROUGH EARLY NEXT WEEK
WITH WIND CHILLS OF AROUND 40 BELOW ZERO SUNDAY NIGHT INTO
TUESDAY. A WIND CHILL WARNING IS IN EFFECT FOR THIS PERIOD. LOW
TEMPERATURES TONIGHT WILL CRASH TO BETWEEN 5 BELOW ZERO AND 18
BELOW ZERO BY DAYBREAK MONDAY.
&&
.UPDATE...
ISSUED AT 810 PM EST SUN JAN 5 2014
UPSTREAM OBSERVATIONAL TRENDS WITHIN LL CAA WING AND ALG NRN
EXTENT OF INTENSE SFC RISE/FALL PRES COUPLET AND NR TERM RUC
GUIDANCE SPURNED EARLIER BLIZZARD UPGRADE OVR WRN AREAS. JUST NOW
SEEING SFC GUSTS OVR 30KTS IN WHITE COUNTY AND XPC THIS TO SPREAD
EWD THROUGH THIS EVENING. RUC PROGS CARRY 40KT SFC WIND MAX UP TO
THE SR 36 CORRIDOR BY 03Z...SR 331 BY 05Z AND SR 15 BY 06Z AND
LASTING FOR ABOUT 6 HOURS BFR ABATING.
THIS MAY AFFECT ERN AREAS AS WELL BUT WILL WATCH TRENDS ACRS WRN
HALF THIS EVENING. HWVR ITS LIKELY THAT AFT SUNRISE...LOCATIONS
SOUTH OF LK SHSN OVR NE IN/NW OH WILL MIX SIGLY AND YIELD CONTD
SIG BLOWING/DRIFTING.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 350 PM EST SUN JAN 5 2014
HEIGHT OF HISTORIC WINTER STORM NOW WELL UNDERWAY ACROSS THE REGION
AT PRESS TIME. CULMINATION OF FACTORS SUPPORTING WIDESPREAD
ACCUMULATIONS OF 10-16 INCHES. COUPLED UPPER LEVEL JET STREAKS
FAVORING EFFECTIVE DIVERGENCE ALOFT WITH SOUTHERN BRANCH
STRENGTHENING TO 170+ KTS OVERNIGHT AND SHOWING A GREAT DEAL OF
CYCLONIC CURVATURE. LOW TO MIDLEVEL FGEN/DEFORMATION RESPONSE IS
SUPERB AND THE TRACK OF THE SURFACE LOW IS NEARLY IDEAL FOR A LONG
DURATION OF HEAVY SNOW IN OUR CWA. WATER VAPOR LOOP SHOWS POLAR
VORTEX PHASING WITH POTENT SOUTHERN STREAM PV ANOMALY AND RAPIDLY
BECOMING NEGATIVELY TILTED. THIS IS NOT ONLY SUPPORTING RAPID
DEEPENING OF THE SURFACE CYCLONE BUT ALSO PULLING IT A BIT TO THE
LEFT AS PREVIOUSLY DISCUSSED. THIS HAS ALLOWED SURFACE TEMPERATURES
TO CLIMB TO AROUND 32F AND WITH WARMER PROFILES ALOFT...CAUSED SNOW
RATIOS TO BE ONLY AROUND 10:1 FOR OUR CENTRAL AND SOUTHEAST
COUNTIES. THIS HAS BEEN ONE POTENTIAL LIMITING FACTOR BUT HAS BEEN
MORE THAN MADE UP FOR WITH IMPRESSIVE QPF TOTALS. MOISTURE
CONVERGENCE IS EXCELLENT WITH 280K MIXING RATIOS APPROACHING 4 G/KG.
ELEVATED INSTABILITY ABOVE ROUGHLY 600MB IS ALSO AIDING HIGHLY
EFFICIENT UVM AND BANDS OF HEAVY SNOWFALL ARE CLEARLY EVIDENT ON
RADAR. SNOWFALL RATES HAVE EXCEEDED 2"/HR IN THESE BANDS. EXPECT
STATUS QUO TO CONTINUE FOR ANOTHER 4-6 HOURS AND WITH ACCUMULATIONS
ALREADY EXCEEDING 8 INCHES IN SOME SPOTS...A FEW STORM TOTALS IN
EXCESS OF 16 INCHES MAY BE POSSIBLE BY LATER TONIGHT. CYCLONE WILL
LIFT RAPIDLY NORTHEAST BY 03Z THOUGH AND EXPECT MOST OF THE SYNOPTIC
SNOW TO WIND DOWN SHORTLY THEREAFTER.
ONE OF THE BIGGEST QUESTIONS REGARDING THIS STORM HAS BEEN THE
POTENTIAL FOR BLIZZARD CONDITIONS. EXPLOSIVE CYCLOGENESIS NOW
UNDERWAY WILL LEAD TO A VERY STRONG ISALLOBARIC COMPONENT TO THE
WIND BY LATER THIS EVENING. COUPLED WITH A TIGHT GRADIENT AND
RELATIVELY DEEP MIXING HEIGHTS...THIS WILL LEAD TO A BRIEF PERIOD OF
30-35 MPH GUSTS WHILE NEW SNOW IS STILL FALLING THIS EVENING. THIS
WILL LEAD TO NEAR BLIZZARD CONDITIONS WITH WIDESPREAD BLOWING AND
DRIFTING SNOW. VISIBILITY REQUIREMENT OF LESS THAN A QUARTER MILE
FOR THREE CONSECUTIVE HOURS IS EXTREMELY TOUGH TO GET IN THIS PART
OF THE COUNTRY THOUGH AND ONLY ONE UPSTREAM STATION (KCMI) HAS
REPORTED SUCH A LOW VISIBILITY. AFTER FURTHER COLLABORATION WITH
NEIGHBORING OFFICES...DECIDED TO HOLD OFF ON A BLIZZARD WARNING
UNLESS NEW OBSERVATIONAL EVIDENCE SUGGESTS OTHERWISE THIS EVENING.
SIGNIFICANT IMPACTS WILL CONTINUE THROUGH THE OVERNIGHT AND INTO
TOMORROW. MODEST LAKE RESPONSE EXPECTED GIVEN STRONG INSTABILITY AND
LINGERING SYNOPTIC MOISTURE. WINDS WILL QUICKLY BACK TO A WESTERLY
DIRECTION THIS EVENING AND THE BULK OF THE ADDITIONAL ACCUMULATION
OVERNIGHT AND INTO TOMORROW WILL BE MAINLY CONFINED NORTH OF THE
TOLL ROAD. INCREASING DRY AIR ADVECTION AND LOW SNOW RATIOS WILL
LIMIT ADDITIONAL ACCUMULATIONS TO AROUND 2-4 INCHES. BIGGEST HAZARD
WILL BE THE DANGEROUSLY COLD TEMPERATURES/WIND CHILLS. STILL
EXPECTING LOWS TO PLUMMET INTO THE MID TEENS BELOW ZERO BY LATE
TONIGHT WITH NO DIURNAL RECOVERY TOMORROW IN THE FACE OF STRONG CAA.
WIND SPEEDS OF 20-30 MPH WILL GENERATE WIND CHILL TEMPERATURES OF
AROUND -40F. NO CHANGES TO WIND CHILL WARNING NECESSARY.
&&
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 350 PM EST SUN JAN 5 2014
HISTORIC/POTENTIALLY LIFE-THREATENING COLD WILL GIVE WAY TO
SIGNIFICANT WARMING BY END OF THE WEEK. ONLY MINOR CHANGES MADE
GIVEN ONGOING WINTER STORM.
PERIOD WILL START WITH THE MUCH ADVERTISED CORE OF ARCTIC AIR
OVERHEAD AS LOWS STILL ON TARGET TO DROP TO 15 TO 20 BELOW WITH WIND
CHILLS OF 30 TO 45 BELOW INTO MID MORNING TUESDAY. IN ADDITION
EXTREME INSTABILITY WILL BE ONGOING OVER THE LAKE AS DELTA T`S ALL
THE WAY TO 700 MB TOP OUT AROUND 30 C WITH INVERSION HGTS AROUND
8000 FT. LIGHT TO MODERATE SNOW SHOULD BE OCCURRING BUT GENERAL
WESTERLY FLOW WILL KEEP MOST SNOW CONFINED TO FAR SOUTHERN LOWER
MICHIGAN. HAVE INCREASED POPS INTO CAT RANGE ACROSS N BERRIEN COUNTY
IN MOST FAVORABLE AREA AND NUDGED UP ACCUMS A TOUCH. ONE MORE BITTER
COLD DAY IN STORE FOR TUESDAY ALTHOUGH SOME AREAS WILL BE A GOOD 5
TO 10 DEGREES WARMER THAN MONDAY. NEVERTHELESS..ONLY LOCATIONS
ALONG THE LAKE WILL SEE TEMPS CLIMB ABOVE ZERO. WINDS WILL STILL BE
IN THE 10 TO 20 MPH RANGE WILL RESULT IN WIDESPREAD DRIFTING...BUT
ACTUAL BLOWING SNOW/REDUCED VSBYS WILL PROBABLY BE ISOLATED. FOR NOW
WILL LEAVE OUT OF GRIDS FOR BOTH MONDAY NIGHT AND TUESDAY.
CENTER OF POLAR VORTEX WILL RETREAT NORTH TO EAST OF HUDSON BAY
ALLOWING HGTS TO INCREASE AND THE START OF A WARMUP WHICH LOOKS TO
LAST THROUGH THE LONG TERM PERIOD. THIS WILL BRING CHALLENGES OF ITS
OWN AS ACTIVE FLOW CONTINUES WITH SEVERAL WAVES MOVING IN FOR
CHANCES FOR SNOW OR EVENTUALLY A MIXED BAG. IN ADDITION TO PRECIP
CHANCES TEMPS SHOULD RISE TO ABOVE FREEZING FOR HIGHS FRI-SUN INTO
THE 30S. EURO GUIDANCE CONTINUES TO POINT TOWARDS HIGHS IN THE 40S
AND MEX NOW TRYING FOLLOW SUIT. WHILE NOT IMPOSSIBLE...AMOUNT OF
SNOWPACK ACROSS THE AREA WILL LIKELY LIMIT FULL
POTENTIAL...ESPECIALLY FRIDAY WITH BEST CHANCE FOR 40S POSSIBLY BY
SUNDAY. THE INCREASING TEMPS WILL CAUSE A RELEASE OF THE SNOWPACK
AND WILL RESULT IN RISING RIVER LEVELS AND INCREASED CONCERNS FOR
BOTH RIVER AND LOW LYING FLOODING. HAVE GENERALLY KEPT FORECAST AS
IS THROUGH THIS TIME FRAME WITH TIMING/TRACK OF EACH WAVE LIKELY TO
VARY OVER THE NEXT SEVERAL DAYS. FOR NOW WITH SO MANY OTHER DETAILS
IN THE HWO...WILL HOLD OFF ON MENTION IN HWO AS DURATION OF RELEASE
COULD BE OVER A LONG ENOUGH PERIOD TO KEEP RISKS MINIMIZED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 627 PM EST SUN JAN 5 2014
INTENSE COMMAHEAD DEFORMATION ZONE CONTS ACRS NRN IN THIS EVENING
W/HEAVY SNOW IN MOST LOCATIONS INCLUDING THE TERMINALS. LIFR CONDS
IN HEAVY SNOW WILL CONT THROUGH APPROX 02Z BFR DIMINISHING RAPIDLY
THROUGH 06Z. DEFORMATION BAND JUST NOW EXITING EAST OF KSBN BUT
RAPID UPSTREAM DVLPMNT OF INTENSE LK ENHANCED BAND WILL SWING INTO
KSBN VCNTY TWD 02-03Z BUT WILL AWAIT EVOLUTION NXT FEW HOURS AND
REACCESS. HWVR WINDS RAMP EXPONENTIALLY WITH GUSTS TO 35KTS LIKELY
BASED ON UPSTREAM OBS AND SHLD YIELD A PROLONGED PD OF BLSN
OVERNIGHT WHICH SHLD IMPROVE SOME MON AM.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER STORM WARNING UNTIL 7 AM EST MONDAY FOR INZ006>009-017-
018-025>027-033-034.
WIND CHILL WARNING FROM 1 AM EST /MIDNIGHT CST/ MONDAY TO 8 PM
EST /7 PM CST/ TUESDAY FOR INZ003>009-012>018-020-022>027-
032>034.
BLIZZARD WARNING UNTIL 7 AM EST /6 AM CST/ MONDAY FOR INZ003>005-
012>016-020-022>024-032.
MI...WINTER STORM WARNING UNTIL 7 AM EST MONDAY FOR MIZ079>081.
WIND CHILL WARNING FROM 1 AM MONDAY TO 8 PM EST TUESDAY FOR
MIZ077>081.
BLIZZARD WARNING UNTIL 4 AM EST MONDAY FOR MIZ077-078.
OH...WINTER STORM WARNING UNTIL 7 AM EST MONDAY FOR OHZ001-002-004-
005-015-016-024-025.
WIND CHILL WARNING FROM 1 AM MONDAY TO 8 PM EST TUESDAY FOR
OHZ001-002-004-005-015-016-024-025.
LM...HEAVY FREEZING SPRAY WARNING UNTIL 4 AM EST TUESDAY FOR LMZ043-
046.
GALE WARNING UNTIL 4 AM EST TUESDAY FOR LMZ043-046.
&&
$$
UPDATE...T
SYNOPSIS...LASHLEY
SHORT TERM...AGD
LONG TERM...FISHER
AVIATION...T
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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
101 PM CST SAT JAN 4 2014
.UPDATE...
ISSUED AT 1255 PM CST SAT JAN 4 2014
HAVE ISSUED A WINTER WEATHER ADVISORY FOR TONIGHT AND SUNDAY FOR
EXTREME NORTHEAST MO...EXTREME SE IA AND WESTERN IL. STORM SYSTEM
WILL BE TRACKING FROM THE SOUTHERN PLAINS INTO OHIO AND IT APPEARS
THAT 2 TO 5 INCHES WILL OCCUR IN OUR SE CWA. COMBINE THIS WITH
WIND GUSTS OVER 30 MPH AND THERE SHOULD BE CONSIDERABLE BLOWING
AND DRIFTING. THERE IS A POSSIBILITY LATER SHIFTS MAY NEED TO GO
WITH A WINTER STORM WARNING IF THE TRACK OF THE STORM IS FARTHER NORTH.
UPDATE ISSUED AT 1155 AM CST SAT JAN 4 2014
ARCTIC FRONT LATE THIS MORNING EXTENDED FROM JUST WEST OF DUBUQUE
TO IOWA CITY AND THEN TO KANSAS CITY. AHEAD OF THE FRONT
TEMPERATURES HAVE PUSHED INTO THE LOWER TO MID 30S BUT BEHIND THE
FRONT READINGS HAD FALLEN TO 12 ABOVE IN NW IA BUT WERE BELOW ZERO
FROM ND TO NORTHERN MN. THE FRONT WILL CONTINUE TO PUSH EASTWARD
ACROSS THE CWA AS THE AFTERNOON PROGRESSES WITH FALLING TEMPERATURES.
BAND OF LIGHT SNOW HAS DEVELOPED AHEAD OF THE FRONT IN EASTERN IA
AND NW IL AND HAVE RAISED POPS TO LIKELY WITH ACCUMULATIONS OF
LESS THAN AN INCH THIS AFTERNOON.
UPDATE ISSUED AT 722 AM CST SAT JAN 4 2014
I HAVE SENT A FEW UPDATES TO CLOUD AND PRECIPITATION TRENDS. THE
LARGEST SIGNIFICANCE IS TO GREATLY INCREASE MORNING POPS ALONG AND
NORTH OF INTERSTATE 80. THE RAP MODEL CONTINUES TO SHOW
DEVELOPMENT OF A BAND OF ACCUMULATING SNOW NEAR THIS AXIS...AND
RECENT RADAR TRENDS SHOW ONE DEVELOPING THIS PAST HOUR. THIS WILL
BE CLOSELY WATCHED...AND AMOUNTS OF SNOW MAY NEED TO BE ADDED
EARLY TODAY ALONG AND JUST NORTH OF INTERSTATE 80.
ERVIN
&&
.SYNOPSIS...
ISSUED AT 236 AM CST SAT JAN 4 2014
THE LATEST SURFACE ANALYSIS SHOWS A COLD FRONT FROM THE MINNESOTA
ARROWHEAD SOUTHWEST THROUGH SOUTHEASTERN SOUTH DAKOTA INTO SOUTH
CENTRAL NEBRASKA. STRONG SOUTHERLY FLOW CONTINUED AHEAD OF THE
FRONT CAUSING SOME PATCHY BLOWING SNOW OVER THE MID MISSISSIPPI
VALLEY. PRECIPITATION WITH THE COLD FRONT WAS MAINLY FOCUSED OVER
NORTHEAST MINNESOTA AND NORTHERN WISCONSIN JUST AHEAD OF A WAVE
ALONG THE BOUNDARY. THE 00Z H8 ANALYSIS HAD THE 850 COLD FRONT FROM
THE EASTERN DAKOTAS INTO THE WESTERN NEBRASKA WITH A WEDGE OF WARM
AIR NOSING INTO NORTHERN SOUTH DAKOTA. THE COLDER AIR AS STILL
BOTTLED UP ALONG THE CANADIAN BORDER. AT 500MB A BROAD TROF WAS
LOCATED OVER THE NORTHERN ROCKIES WITH A CLOSED LOW OVER NORTHERN
ALBERTA. AN IMPRESSIVE AREA OF HEIGHT FALLS...LOCATED AHEAD OF THE
CLOSED LOW...EXTENDED FROM SASKATCHEWAN INTO THE CENTRAL ROCKIES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 236 AM CST SAT JAN 4 2014
THE SURFACE COLD FRONT WILL MOVE THROUGH THE CWFA THIS MORNING AND
EARLY THIS AFTERNOON. MODELS ARE CONSISTENT SHOWING THE
PRECIPITATION/SNOW OCCURRING BEHIND THE FRONT AND DEVELOPING AS THE
FRONT MOVES THROUGH THE REGION. THE LATEST PROGS SUGGEST THE SNOW
WILL BE DEVELOPING OVER THE NORTHWEST CWA THIS MORNING...AND THEN
BECOME MORE ORGANIZED/WIDESPREAD DURING THE LATE AFTERNOON AND
EVENING OVER THE SOUTHEASTERN HALF OF THE FORECAST AREA. KEPT
CHANCE POPS OVER THE NORTHWEST THIS MORNING. POPS WERE SHIFTED TO
THE SOUTHEAST AND INCREASED TO LIKELY/CATEGORICAL DURING THE
AFTERNOON AND OVERNIGHT. LOOKING AT FORCING WITH THE
BOUNDARY...MODEL PROGS SHOWN A PROLONGED PERIOD OF FGEN OVER THE
AREA THIS AFTERNOON INTO TONIGHT...BUT IT DOES NOT LOOK THAT
ORGANIZED. TIME SECTIONS ARE SIMILAR...DEPICTING A PROLONGED PERIOD
OF AT LEAST MID LEVEL WEAK LIFT. WITH THE FORCING LACKING GOOD
ORGANIZATION HAVE OPTED TO KEEP PRECIPITATION AMOUNTS IN LINE WITH
THE DRIER GFS/ECMWF PROGS WITH PRECIP AMOUNTS UP TO A QUARTER OF AN
INCH OVER THE SOUTHEAST HALF OF THE CWFA. USING SNOW TO LIQUID
RATIOS AROUND 16 TO 1 THAT YIELD UP TO 3 INCHES OF SNOW BY SUNDAY
MORNING OVER THE SOUTHEAST HALF WITH THE HIGHER AMOUNTS OVER THE FAR
SOUTHEAST CORNER. WITH THESE FORECAST SNOW AMOUNTS AND WINDS NOT
EXPECTED TO BE VERY STRONG...SIGNIFICANT BLOWING SNOW SHOULD NOT BE
A CONCERN. NO WINTER WX ADVISORY IS PLANNED AT THIS TIME FOR THIS
AFTERNOON OR TONIGHT.
AS FOR TEMPERATURES TODAY...HIGHS SHOULD BE REACHED EARLY WITH
SLOWLY FALLING TEMPERATURES DURING THE AFTERNOON. BY SUNDAY MORNING
READINGS WILL BE BACK IN THE SINGLE DIGITS WITH SUB ZERO TEMPS OVER
THE NORTHWEST. WIND CHILLS WILL BE APPROACHING -30 BY 6AM SUNDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 236 AM CST SAT JAN 4 2014
THIS MORNINGS 20S WILL BE A DISTANT MEMORY SUNDAY MORNING...AS
INCREASINGLY STRONG ARCTIC COLD ADVECTION WILL BE WELL UNDERWAY. THE
MAIN CHALLENGE DURING THIS INITIAL PERIOD WILL BE ENDING ANY SNOW IN
THE EAST...AND TIMING ON THE ONSET OF WIND CHILL HEADLINES. THE
HEADLINES FOR WIND CHILL ARE THE HIGHEST CONCERN...AND KEEPING THE
MESSAGE CONSISTENT AND AS SIMPLE AS POSSIBLE HAS BEEN OUR GOAL ON
THIS ISSUANCE. PURE METEOROLOGICALLY...SUNDAY WILL BE MAINLY AN
ADVISORY DAY UNTIL LATE AFTERNOON...AS WILL TUESDAY MID
MORNING...HOWEVER...THIS IS JUST BRACKETS ON WHAT IS A HIGH
CONFIDENCE AND LIFE THREATENING WIND CHILL EVENT. A WARNING WILL BE
ISSUED FOR THE PRIOR WATCH COUNTIES IN THE NORTHWEST STARTING AT 6
AM SUNDAY MORNING...THEN THE REMAINDER OF COUNTIES WILL BEGIN AT
NOON SUNDAY. THIS ROUGHLY MATCHES THE WATCH...AND KEEP THE MESSAGE
CONSISTENT. BY FAR...THE WORST CONDITIONS WILL BE SUNDAY NIGHT
THROUGH MONDAY NIGHT...WITH A PROLONGED PERIOD OF -35 TO -45 CHILLS
AREA WIDE. THE NORTH HALF SHOULD MAX OUR WIND CHILL INTENSITY IN THE
-48 TO -53 BETWEEN 4 AM MONDAY AND 9 AM MONDAY. ACTUAL TEMPERATURES
WILL SLOWLY FALL SUNDAY WITHIN THE -5 TO +7 TEMPERATURE RANGE. BY
SUNDAY AT 6 PM...WE ARE ALREADY EXPECTING ACTUAL TEMPERATURES TO BY
-10 NORTHWEST TO -2 SOUTHEAST. LOWS SUNDAY NIGHT APPEAR SET THROUGH
PURE COLD ADVECTION/NO RADIATIONAL COOLING TO REACH -19 TO -25 IN
THE NORTH 1/2 TO -14 TO -19 IN THE SOUTH HALF. WINDS OVERNIGHT WILL
BE STRONG...SUSTAINED AROUND 20 TO 25 MPH...GUSTING TO 30 TO 35 MPH.
THIS IS WHY THE WIND CHILLS WILL BE SO EXCRUCIATINGLY COLD. SIMILAR
WINDS WILL CONTINUE THROUGH EARLY MONDAY EVENING...BEFORE SLOWLY
BACKING DOWN. IF ANYTHING...THIS MAY BE SLIGHTLY UNDERDONE GIVEN THE
WHOPPING GRADIENT BETWEEN A STRENGTHENING SUB 1000MB LOW IN THE
EASTERN GREAT LAKES...AND A ASTOUNDINGLY STRONG 1050+ MB HIGH
ENTERING MONTANA. THIS GRADIENT MAY CREATE LEGITIMATE BLOWING SNOW
THREAT SUNDAY AND SUNDAY NIGHT. IN ADDITION...INTENSE ADVECTION OF
ARCTIC AIR WILL KEEP THE BOUNDARY LAYER MIXED CONTINUOUSLY...WHICH
OFTEN IS UNDERPLAYED BY MODELS.
BEYOND TUESDAY...A WARM UP IS FORECAST...BUT IT WILL TAKE SEVERAL
DAYS TO RID THE REGION OF ARCTIC AIR. SOME OVER RUNNING SNOWS IS A
GROWING THREAT FOR WEDNESDAY AND THURSDAY...BUT AT THIS
POINT...MODELS DO NOT SHOW STRONG ENOUGH DYNAMICS TO CREATE MUCH OF
A STORM THREAT.
ERVIN
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1155 AM CST SAT JAN 4 2014
A VERY STRONG COLD FRONT WILL CONTINUE TO SWEEP THROUGH EASTERN
IOWA AND NORTHWEST ILLINOIS THIS AFTERNOON...FOLLOWED BY A MUCH
STRONGER SURGE OF ARCTIC AIR SUNDAY. SOUTHWEST WINDS WILL BECOME
NORTHWEST AT 15 TO 25 KNOTS BEHIND THE FRONT. LIGHT SNOW SHOULD
DEVELOP JUST BEHIND THE FRONT...AND BECOME WIDESPREAD FOR A TIME
IN SOUTHEAST IOWA AND ILLINOIS. MLI AND BRL WILL LIKELY SEE IFR
VISIBILITIES IN SNOW TOWARD VERY LATE AFTERNOON AND EARLY EVENING.
THIS SNOW MAY CONTINUE THROUGH MID MORNING SUNDAY BEFORE ENDING IN
ILLINOIS. IT IS UNLIKELY THAT MLI AND BRL WILL SEE SNOW CONTINUE
BEYOND 12Z SUNDAY. VERY COLD AIR WILL BE FOUND THROUGH THE DAY
SUNDAY. STRONG NORTHWEST WINDS OF 20 TO 30 KTS WILL CONTINUE FROM
LATER TONIGHT THROUGH MONDAY NIGHT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WIND CHILL WARNING FROM 6 AM SUNDAY TO NOON CST TUESDAY FOR
BENTON-BUCHANAN-DELAWARE-DUBUQUE-JACKSON-JONES-LINN.
WIND CHILL WARNING FROM NOON SUNDAY TO NOON CST TUESDAY FOR
CEDAR-CLINTON-DES MOINES-HENRY IA-IOWA-JEFFERSON-JOHNSON-
KEOKUK-LEE-LOUISA-MUSCATINE-SCOTT-VAN BUREN-WASHINGTON.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 6 PM CST
SUNDAY FOR LEE.
IL...WIND CHILL WARNING FROM 6 AM SUNDAY TO NOON CST TUESDAY FOR JO
DAVIESS.
WIND CHILL WARNING FROM NOON SUNDAY TO NOON CST TUESDAY FOR
BUREAU-CARROLL-HANCOCK-HENDERSON-HENRY IL-MCDONOUGH-MERCER-
PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 6 PM CST
SUNDAY FOR BUREAU-HANCOCK-HENDERSON-HENRY IL-MCDONOUGH-
PUTNAM-WARREN.
MO...WIND CHILL WARNING FROM NOON SUNDAY TO NOON CST TUESDAY FOR
CLARK-SCOTLAND.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 6 PM CST
SUNDAY FOR CLARK-SCOTLAND.
&&
$$
UPDATE...HAASE
SYNOPSIS...DLF
SHORT TERM...DLF
LONG TERM...ERVIN
AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1158 AM CST SAT JAN 4 2014
.UPDATE...
ISSUED AT 1155 AM CST SAT JAN 4 2014
ARCTIC FRONT LATE THIS MORNING EXTENDED FROM JUST WEST OF DUBUQUE
TO IOWA CITY AND THEN TO KANSAS CITY. AHEAD OF THE FRONT
TEMPERATURES HAVE PUSHED INTO THE LOWER TO MID 30S BUT BEHIND THE
FRONT READINGS HAD FALLEN TO 12 ABOVE IN NW IA BUT WERE BELOW ZERO
FROM ND TO NORTHERN MN. THE FRONT WILL CONTINUE TO PUSH EASTWARD
ACROSS THE CWA AS THE AFTERNOON PROGRESSES WITH FALLING TEMPERATURES.
BAND OF LIGHT SNOW HAS DEVELOPED AHEAD OF THE FRONT IN EASTERN IA
AND NW IL AND HAVE RAISED POPS TO LIKELY WITH ACCUMULATIONS OF
LESS THAN AN INCH THIS AFTERNOON.
UPDATE ISSUED AT 722 AM CST SAT JAN 4 2014
I HAVE SENT A FEW UPDATES TO CLOUD AND PRECIPITATION TRENDS. THE
LARGEST SIGNIFICANCE IS TO GREATLY INCREASE MORNING POPS ALONG AND
NORTH OF INTERSTATE 80. THE RAP MODEL CONTINUES TO SHOW
DEVELOPMENT OF A BAND OF ACCUMULATING SNOW NEAR THIS AXIS...AND
RECENT RADAR TRENDS SHOW ONE DEVELOPING THIS PAST HOUR. THIS WILL
BE CLOSELY WATCHED...AND AMOUNTS OF SNOW MAY NEED TO BE ADDED
EARLY TODAY ALONG AND JUST NORTH OF INTERSTATE 80.
ERVIN
&&
.SYNOPSIS...
ISSUED AT 236 AM CST SAT JAN 4 2014
THE LATEST SURFACE ANALYSIS SHOWS A COLD FRONT FROM THE MINNESOTA
ARROWHEAD SOUTHWEST THROUGH SOUTHEASTERN SOUTH DAKOTA INTO SOUTH
CENTRAL NEBRASKA. STRONG SOUTHERLY FLOW CONTINUED AHEAD OF THE
FRONT CAUSING SOME PATCHY BLOWING SNOW OVER THE MID MISSISSIPPI
VALLEY. PRECIPITATION WITH THE COLD FRONT WAS MAINLY FOCUSED OVER
NORTHEAST MINNESOTA AND NORTHERN WISCONSIN JUST AHEAD OF A WAVE
ALONG THE BOUNDARY. THE 00Z H8 ANALYSIS HAD THE 850 COLD FRONT FROM
THE EASTERN DAKOTAS INTO THE WESTERN NEBRASKA WITH A WEDGE OF WARM
AIR NOSING INTO NORTHERN SOUTH DAKOTA. THE COLDER AIR AS STILL
BOTTLED UP ALONG THE CANADIAN BORDER. AT 500MB A BROAD TROF WAS
LOCATED OVER THE NORTHERN ROCKIES WITH A CLOSED LOW OVER NORTHERN
ALBERTA. AN IMPRESSIVE AREA OF HEIGHT FALLS...LOCATED AHEAD OF THE
CLOSED LOW...EXTENDED FROM SASKATCHEWAN INTO THE CENTRAL ROCKIES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 236 AM CST SAT JAN 4 2014
THE SURFACE COLD FRONT WILL MOVE THROUGH THE CWFA THIS MORNING AND
EARLY THIS AFTERNOON. MODELS ARE CONSISTENT SHOWING THE
PRECIPITATION/SNOW OCCURRING BEHIND THE FRONT AND DEVELOPING AS THE
FRONT MOVES THROUGH THE REGION. THE LATEST PROGS SUGGEST THE SNOW
WILL BE DEVELOPING OVER THE NORTHWEST CWA THIS MORNING...AND THEN
BECOME MORE ORGANIZED/WIDESPREAD DURING THE LATE AFTERNOON AND
EVENING OVER THE SOUTHEASTERN HALF OF THE FORECAST AREA. KEPT
CHANCE POPS OVER THE NORTHWEST THIS MORNING. POPS WERE SHIFTED TO
THE SOUTHEAST AND INCREASED TO LIKELY/CATEGORICAL DURING THE
AFTERNOON AND OVERNIGHT. LOOKING AT FORCING WITH THE
BOUNDARY...MODEL PROGS SHOWN A PROLONGED PERIOD OF FGEN OVER THE
AREA THIS AFTERNOON INTO TONIGHT...BUT IT DOES NOT LOOK THAT
ORGANIZED. TIME SECTIONS ARE SIMILAR...DEPICTING A PROLONGED PERIOD
OF AT LEAST MID LEVEL WEAK LIFT. WITH THE FORCING LACKING GOOD
ORGANIZATION HAVE OPTED TO KEEP PRECIPITATION AMOUNTS IN LINE WITH
THE DRIER GFS/ECMWF PROGS WITH PRECIP AMOUNTS UP TO A QUARTER OF AN
INCH OVER THE SOUTHEAST HALF OF THE CWFA. USING SNOW TO LIQUID
RATIOS AROUND 16 TO 1 THAT YIELD UP TO 3 INCHES OF SNOW BY SUNDAY
MORNING OVER THE SOUTHEAST HALF WITH THE HIGHER AMOUNTS OVER THE FAR
SOUTHEAST CORNER. WITH THESE FORECAST SNOW AMOUNTS AND WINDS NOT
EXPECTED TO BE VERY STRONG...SIGNIFICANT BLOWING SNOW SHOULD NOT BE
A CONCERN. NO WINTER WX ADVISORY IS PLANNED AT THIS TIME FOR THIS
AFTERNOON OR TONIGHT.
AS FOR TEMPERATURES TODAY...HIGHS SHOULD BE REACHED EARLY WITH
SLOWLY FALLING TEMPERATURES DURING THE AFTERNOON. BY SUNDAY MORNING
READINGS WILL BE BACK IN THE SINGLE DIGITS WITH SUB ZERO TEMPS OVER
THE NORTHWEST. WIND CHILLS WILL BE APPROACHING -30 BY 6AM SUNDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 236 AM CST SAT JAN 4 2014
THIS MORNINGS 20S WILL BE A DISTANT MEMORY SUNDAY MORNING...AS
INCREASINGLY STRONG ARCTIC COLD ADVECTION WILL BE WELL UNDERWAY. THE
MAIN CHALLENGE DURING THIS INITIAL PERIOD WILL BE ENDING ANY SNOW IN
THE EAST...AND TIMING ON THE ONSET OF WIND CHILL HEADLINES. THE
HEADLINES FOR WIND CHILL ARE THE HIGHEST CONCERN...AND KEEPING THE
MESSAGE CONSISTENT AND AS SIMPLE AS POSSIBLE HAS BEEN OUR GOAL ON
THIS ISSUANCE. PURE METEOROLOGICALLY...SUNDAY WILL BE MAINLY AN
ADVISORY DAY UNTIL LATE AFTERNOON...AS WILL TUESDAY MID
MORNING...HOWEVER...THIS IS JUST BRACKETS ON WHAT IS A HIGH
CONFIDENCE AND LIFE THREATENING WIND CHILL EVENT. A WARNING WILL BE
ISSUED FOR THE PRIOR WATCH COUNTIES IN THE NORTHWEST STARTING AT 6
AM SUNDAY MORNING...THEN THE REMAINDER OF COUNTIES WILL BEGIN AT
NOON SUNDAY. THIS ROUGHLY MATCHES THE WATCH...AND KEEP THE MESSAGE
CONSISTENT. BY FAR...THE WORST CONDITIONS WILL BE SUNDAY NIGHT
THROUGH MONDAY NIGHT...WITH A PROLONGED PERIOD OF -35 TO -45 CHILLS
AREA WIDE. THE NORTH HALF SHOULD MAX OUR WIND CHILL INTENSITY IN THE
-48 TO -53 BETWEEN 4 AM MONDAY AND 9 AM MONDAY. ACTUAL TEMPERATURES
WILL SLOWLY FALL SUNDAY WITHIN THE -5 TO +7 TEMPERATURE RANGE. BY
SUNDAY AT 6 PM...WE ARE ALREADY EXPECTING ACTUAL TEMPERATURES TO BY
-10 NORTHWEST TO -2 SOUTHEAST. LOWS SUNDAY NIGHT APPEAR SET THROUGH
PURE COLD ADVECTION/NO RADIATIONAL COOLING TO REACH -19 TO -25 IN
THE NORTH 1/2 TO -14 TO -19 IN THE SOUTH HALF. WINDS OVERNIGHT WILL
BE STRONG...SUSTAINED AROUND 20 TO 25 MPH...GUSTING TO 30 TO 35 MPH.
THIS IS WHY THE WIND CHILLS WILL BE SO EXCRUCIATINGLY COLD. SIMILAR
WINDS WILL CONTINUE THROUGH EARLY MONDAY EVENING...BEFORE SLOWLY
BACKING DOWN. IF ANYTHING...THIS MAY BE SLIGHTLY UNDERDONE GIVEN THE
WHOPPING GRADIENT BETWEEN A STRENGTHENING SUB 1000MB LOW IN THE
EASTERN GREAT LAKES...AND A ASTOUNDINGLY STRONG 1050+ MB HIGH
ENTERING MONTANA. THIS GRADIENT MAY CREATE LEGITIMATE BLOWING SNOW
THREAT SUNDAY AND SUNDAY NIGHT. IN ADDITION...INTENSE ADVECTION OF
ARCTIC AIR WILL KEEP THE BOUNDARY LAYER MIXED CONTINUOUSLY...WHICH
OFTEN IS UNDERPLAYED BY MODELS.
BEYOND TUESDAY...A WARM UP IS FORECAST...BUT IT WILL TAKE SEVERAL
DAYS TO RID THE REGION OF ARCTIC AIR. SOME OVER RUNNING SNOWS IS A
GROWING THREAT FOR WEDNESDAY AND THURSDAY...BUT AT THIS
POINT...MODELS DO NOT SHOW STRONG ENOUGH DYNAMICS TO CREATE MUCH OF
A STORM THREAT.
ERVIN
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1155 AM CST SAT JAN 4 2014
A VERY STRONG COLD FRONT WILL CONTINUE TO SWEEP THROUGH EASTERN
IOWA AND NORTHWEST ILLINOIS THIS AFTERNOON...FOLLOWED BY A MUCH
STRONGER SURGE OF ARCTIC AIR SUNDAY. SOUTHWEST WINDS WILL BECOME
NORTHWEST AT 15 TO 25 KNOTS BEHIND THE FRONT. LIGHT SNOW SHOULD
DEVELOP JUST BEHIND THE FRONT...AND BECOME WIDESPREAD FOR A TIME
IN SOUTHEAST IOWA AND ILLINOIS. MLI AND BRL WILL LIKELY SEE IFR
VISIBILITIES IN SNOW TOWARD VERY LATE AFTERNOON AND EARLY EVENING.
THIS SNOW MAY CONTINUE THROUGH MID MORNING SUNDAY BEFORE ENDING IN
ILLINOIS. IT IS UNLIKELY THAT MLI AND BRL WILL SEE SNOW CONTINUE
BEYOND 12Z SUNDAY. VERY COLD AIR WILL BE FOUND THROUGH THE DAY
SUNDAY. STRONG NORTHWEST WINDS OF 20 TO 30 KTS WILL CONTINUE FROM
LATER TONIGHT THROUGH MONDAY NIGHT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WIND CHILL WARNING FROM 6 AM SUNDAY TO NOON CST TUESDAY FOR
BENTON-BUCHANAN-DELAWARE-DUBUQUE-JACKSON-JONES-LINN.
WIND CHILL WARNING FROM NOON SUNDAY TO NOON CST TUESDAY FOR
CEDAR-CLINTON-DES MOINES-HENRY IA-IOWA-JEFFERSON-JOHNSON-
KEOKUK-LEE-LOUISA-MUSCATINE-SCOTT-VAN BUREN-WASHINGTON.
IL...WIND CHILL WARNING FROM 6 AM SUNDAY TO NOON CST TUESDAY FOR JO
DAVIESS.
WIND CHILL WARNING FROM NOON SUNDAY TO NOON CST TUESDAY FOR
BUREAU-CARROLL-HANCOCK-HENDERSON-HENRY IL-MCDONOUGH-MERCER-
PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE.
MO...WIND CHILL WARNING FROM NOON SUNDAY TO NOON CST TUESDAY FOR
CLARK-SCOTLAND.
&&
$$
UPDATE...HAASE
SYNOPSIS...DLF
SHORT TERM...DLF
LONG TERM...ERVIN
AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
725 AM CST SAT JAN 4 2014
.UPDATE...
ISSUED AT 722 AM CST SAT JAN 4 2014
I HAVE SENT A FEW UPDATES TO CLOUD AND PRECIPITATION TRENDS. THE
LARGEST SIGNIFICANCE IS TO GREATLY INCREASE MORNING POPS ALONG AND
NORTH OF INTERSTATE 80. THE RAP MODEL CONTINUES TO SHOW
DEVELOPMENT OF A BAND OF ACCUMULATING SNOW NEAR THIS AXIS...AND
RECENT RADAR TRENDS SHOW ONE DEVELOPING THIS PAST HOUR. THIS WILL
BE CLOSELY WATCHED...AND AMOUNTS OF SNOW MAY NEED TO BE ADDED
EARLY TODAY ALONG AND JUST NORTH OF INTERSTATE 80.
ERVIN
&&
.SYNOPSIS...
ISSUED AT 236 AM CST SAT JAN 4 2014
THE LATEST SURFACE ANALYSIS SHOWS A COLD FRONT FROM THE MINNESOTA
ARROWHEAD SOUTHWEST THROUGH SOUTHEASTERN SOUTH DAKOTA INTO SOUTH
CENTRAL NEBRASKA. STRONG SOUTHERLY FLOW CONTINUED AHEAD OF THE
FRONT CAUSING SOME PATCHY BLOWING SNOW OVER THE MID MISSISSIPPI
VALLEY. PRECIPITATION WITH THE COLD FRONT WAS MAINLY FOCUSED OVER
NORTHEAST MINNESOTA AND NORTHERN WISCONSIN JUST AHEAD OF A WAVE
ALONG THE BOUNDARY. THE 00Z H8 ANALYSIS HAD THE 850 COLD FRONT FROM
THE EASTERN DAKOTAS INTO THE WESTERN NEBRASKA WITH A WEDGE OF WARM
AIR NOSING INTO NORTHERN SOUTH DAKOTA. THE COLDER AIR AS STILL
BOTTLED UP ALONG THE CANADIAN BORDER. AT 500MB A BROAD TROF WAS
LOCATED OVER THE NORTHERN ROCKIES WITH A CLOSED LOW OVER NORTHERN
ALBERTA. AN IMPRESSIVE AREA OF HEIGHT FALLS...LOCATED AHEAD OF THE
CLOSED LOW...EXTENDED FROM SASKATCHEWAN INTO THE CENTRAL ROCKIES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 236 AM CST SAT JAN 4 2014
THE SURFACE COLD FRONT WILL MOVE THROUGH THE CWFA THIS MORNING AND
EARLY THIS AFTERNOON. MODELS ARE CONSISTENT SHOWING THE
PRECIPITATION/SNOW OCCURRING BEHIND THE FRONT AND DEVELOPING AS THE
FRONT MOVES THROUGH THE REGION. THE LATEST PROGS SUGGEST THE SNOW
WILL BE DEVELOPING OVER THE NORTHWEST CWA THIS MORNING...AND THEN
BECOME MORE ORGANIZED/WIDESPREAD DURING THE LATE AFTERNOON AND
EVENING OVER THE SOUTHEASTERN HALF OF THE FORECAST AREA. KEPT
CHANCE POPS OVER THE NORTHWEST THIS MORNING. POPS WERE SHIFTED TO
THE SOUTHEAST AND INCREASED TO LIKELY/CATEGORICAL DURING THE
AFTERNOON AND OVERNIGHT. LOOKING AT FORCING WITH THE
BOUNDARY...MODEL PROGS SHOWN A PROLONGED PERIOD OF FGEN OVER THE
AREA THIS AFTERNOON INTO TONIGHT...BUT IT DOES NOT LOOK THAT
ORGANIZED. TIME SECTIONS ARE SIMILAR...DEPICTING A PROLONGED PERIOD
OF AT LEAST MID LEVEL WEAK LIFT. WITH THE FORCING LACKING GOOD
ORGANIZATION HAVE OPTED TO KEEP PRECIPITATION AMOUNTS IN LINE WITH
THE DRIER GFS/ECMWF PROGS WITH PRECIP AMOUNTS UP TO A QUARTER OF AN
INCH OVER THE SOUTHEAST HALF OF THE CWFA. USING SNOW TO LIQUID
RATIOS AROUND 16 TO 1 THAT YIELD UP TO 3 INCHES OF SNOW BY SUNDAY
MORNING OVER THE SOUTHEAST HALF WITH THE HIGHER AMOUNTS OVER THE FAR
SOUTHEAST CORNER. WITH THESE FORECAST SNOW AMOUNTS AND WINDS NOT
EXPECTED TO BE VERY STRONG...SIGNIFICANT BLOWING SNOW SHOULD NOT BE
A CONCERN. NO WINTER WX ADVISORY IS PLANNED AT THIS TIME FOR THIS
AFTERNOON OR TONIGHT.
AS FOR TEMPERATURES TODAY...HIGHS SHOULD BE REACHED EARLY WITH
SLOWLY FALLING TEMPERATURES DURING THE AFTERNOON. BY SUNDAY MORNING
READINGS WILL BE BACK IN THE SINGLE DIGITS WITH SUB ZERO TEMPS OVER
THE NORTHWEST. WIND CHILLS WILL BE APPROACHING -30 BY 6AM SUNDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 236 AM CST SAT JAN 4 2014
THIS MORNINGS 20S WILL BE A DISTANT MEMORY SUNDAY MORNING...AS
INCREASINGLY STRONG ARCTIC COLD ADVECTION WILL BE WELL UNDERWAY. THE
MAIN CHALLENGE DURING THIS INITIAL PERIOD WILL BE ENDING ANY SNOW IN
THE EAST...AND TIMING ON THE ONSET OF WIND CHILL HEADLINES. THE
HEADLINES FOR WIND CHILL ARE THE HIGHEST CONCERN...AND KEEPING THE
MESSAGE CONSISTENT AND AS SIMPLE AS POSSIBLE HAS BEEN OUR GOAL ON
THIS ISSUANCE. PURE METEOROLOGICALLY...SUNDAY WILL BE MAINLY AN
ADVISORY DAY UNTIL LATE AFTERNOON...AS WILL TUESDAY MID
MORNING...HOWEVER...THIS IS JUST BRACKETS ON WHAT IS A HIGH
CONFIDENCE AND LIFE THREATENING WIND CHILL EVENT. A WARNING WILL BE
ISSUED FOR THE PRIOR WATCH COUNTIES IN THE NORTHWEST STARTING AT 6
AM SUNDAY MORNING...THEN THE REMAINDER OF COUNTIES WILL BEGIN AT
NOON SUNDAY. THIS ROUGHLY MATCHES THE WATCH...AND KEEP THE MESSAGE
CONSISTENT. BY FAR...THE WORST CONDITIONS WILL BE SUNDAY NIGHT
THROUGH MONDAY NIGHT...WITH A PROLONGED PERIOD OF -35 TO -45 CHILLS
AREA WIDE. THE NORTH HALF SHOULD MAX OUR WIND CHILL INTENSITY IN THE
-48 TO -53 BETWEEN 4 AM MONDAY AND 9 AM MONDAY. ACTUAL TEMPERATURES
WILL SLOWLY FALL SUNDAY WITHIN THE -5 TO +7 TEMPERATURE RANGE. BY
SUNDAY AT 6 PM...WE ARE ALREADY EXPECTING ACTUAL TEMPERATURES TO BY
-10 NORTHWEST TO -2 SOUTHEAST. LOWS SUNDAY NIGHT APPEAR SET THROUGH
PURE COLD ADVECTION/NO RADIATIONAL COOLING TO REACH -19 TO -25 IN
THE NORTH 1/2 TO -14 TO -19 IN THE SOUTH HALF. WINDS OVERNIGHT WILL
BE STRONG...SUSTAINED AROUND 20 TO 25 MPH...GUSTING TO 30 TO 35 MPH.
THIS IS WHY THE WIND CHILLS WILL BE SO EXCRUCIATINGLY COLD. SIMILAR
WINDS WILL CONTINUE THROUGH EARLY MONDAY EVENING...BEFORE SLOWLY
BACKING DOWN. IF ANYTHING...THIS MAY BE SLIGHTLY UNDERDONE GIVEN THE
WHOPPING GRADIENT BETWEEN A STRENGTHENING SUB 1000MB LOW IN THE
EASTERN GREAT LAKES...AND A ASTOUNDINGLY STRONG 1050+ MB HIGH
ENTERING MONTANA. THIS GRADIENT MAY CREATE LEGITIMATE BLOWING SNOW
THREAT SUNDAY AND SUNDAY NIGHT. IN ADDITION...INTENSE ADVECTION OF
ARCTIC AIR WILL KEEP THE BOUNDARY LAYER MIXED CONTINUOUSLY...WHICH
OFTEN IS UNDERPLAYED BY MODELS.
BEYOND TUESDAY...A WARM UP IS FORECAST...BUT IT WILL TAKE SEVERAL
DAYS TO RID THE REGION OF ARCTIC AIR. SOME OVER RUNNING SNOWS IS A
GROWING THREAT FOR WEDNESDAY AND THURSDAY...BUT AT THIS
POINT...MODELS DO NOT SHOW STRONG ENOUGH DYNAMICS TO CREATE MUCH OF
A STORM THREAT.
ERVIN
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 508 AM CST SAT JAN 4 2014
A VERY STRONG COLD FRONT WILL SWEEP THROUGH EASTERN IOWA AND
NORTHWEST ILLINOIS THIS MORNING...FOLLOWED BY A MUCH STRONGER
SURGE OF ARCTIC AIR SUNDAY. THE FRONT TODAY WILL SWITCH THE VFR
CONDITIONS AND SOUTHWEST WINDS OF 15 TO 25 KTS...TO WEST BY MID
MORNING. BY EARLY AFTERNOON...NORTHWEST WINDS OF 15 TO 25 KTS WILL
BECOME PREVALENT AT ALL SITES. LIGHT SNOW SHOULD DEVELOP JUST
BEHIND THE FRONT...AND BECOME WIDESPREAD FOR A TIME IN SOUTHEAST
IOWA AND ILLINOIS. MLI AND BRL WILL LIKELY SEE IFR VISIBILITIES IN
SNOW TOWARD VERY LATE AFTERNOON AND EARLY EVENING. THIS SNOW MAY
CONTINUE THROUGH MID MORNING SUNDAY BEFORE ENDING IN ILLINOIS. IT
IS UNLIKELY THAT MLI AND BRL WILL SEE SNOW CONTINUE BEYOND 12Z
SUNDAY. VERY VERY COLD AIR WILL BE FOUND THROUGH THE DAY SUNDAY.
STRONG NORTHWEST WINDS OF 20 TO 30 KTS WILL CONTINUE FROM LATER
TONIGHT THROUGH MONDAY NIGHT.
ERVIN
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WIND CHILL WARNING FROM 6 AM SUNDAY TO NOON CST TUESDAY FOR
BENTON-BUCHANAN-DELAWARE-DUBUQUE-JACKSON-JONES-LINN.
WIND CHILL WARNING FROM NOON SUNDAY TO NOON CST TUESDAY FOR
CEDAR-CLINTON-DES MOINES-HENRY IA-IOWA-JEFFERSON-JOHNSON-
KEOKUK-LEE-LOUISA-MUSCATINE-SCOTT-VAN BUREN-WASHINGTON.
IL...WIND CHILL WARNING FROM 6 AM SUNDAY TO NOON CST TUESDAY FOR JO
DAVIESS.
WIND CHILL WARNING FROM NOON SUNDAY TO NOON CST TUESDAY FOR
BUREAU-CARROLL-HANCOCK-HENDERSON-HENRY IL-MCDONOUGH-MERCER-
PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE.
MO...WIND CHILL WARNING FROM NOON SUNDAY TO NOON CST TUESDAY FOR
CLARK-SCOTLAND.
&&
$$
UPDATE...ERVIN
SYNOPSIS...DLF
SHORT TERM...DLF
LONG TERM...ERVIN
AVIATION...ERVIN
AREA FORECAST DISCUSSION
NWS TOPEKA KS
524 AM CST Sat Jan 4 2014
...AVIATION UPDATE...
.SHORT TERM...(Today and Tonight)
Issued at 350 AM CST SAT JAN 4 2014
09Z water vapor imagery shows a broad upper level trough over much
of the country with one shortwave over the northern plains moving
towards MN and another shortwave digging southeast from ID towards
CO. At the surface a pre frontal trough has moved into north central
KS with the strong cold air advection lagging the wind shift by
about 125 miles.
For today and tonight, we should have good mid level frontogenesis
move across the forecast area. However the lack of a well organized
shortwave to provide good large scale forcing suggests snow amounts
will be relatively light. Additionally the better large scale
forcing is initially waisted on trying to saturate the column this
morning and into the early afternoon. There does appear to be some
conditional symmetric instability (CSI) just above the frontal
circulation which may be able to enhance snow rates. And with very
cold air moving in this evening, snow to water ratios are expected
to approach 20:1 overnight. So even with light QPF amounts, there is
the potential for 1 to 2 inches with locally higher amounts.
Ensemble mean progs generally support this idea of 1 to 2 inches. At
this point the area most likely to see the higher amounts looks to
be across east central KS since snowfall is expected to occur while
the ratios are highest. This would give areas along and southeast of
the KS turnpike around 2 inches by Sunday morning. With this in mind
and the potential for CSI to cause a local enhancement, will issue a
low end winter weather advisory beginning late this afternoon and
continuing into Sunday morning.
Because the cold air advection is lagging the front by a pretty
significant margin, have increased highs across east central KS into
the upper 30s with temps falling through the afternoon. Think the
cold air advection and increasing cloud cover will also cause temps
to fall across northern parts of the area this afternoon. Did not go
quite as cold for lows Sunday as MOS guidance would suggest since
north winds should keep the boundary layer mixed and skies remaining
mostly cloudy. So Lows are pretty similar to the previous forecast
with temps expected to fall between 5 and 10 degrees above zero.
Wolters
.LONG TERM...(Sunday through Friday)
Issued at 350 AM CST SAT JAN 4 2014
The upper shortwave trough continues to exit eastward on Sunday.
Lingering light snow is possible through the morning period mainly
for areas southeast of Interstate 35.
Attention quickly turns to the abnormally cold air as northerly
winds increase between 10 and 20 mph sustained Sunday afternoon.
Gusts near 25 mph combined with falling h85 temps well below zero
will result in wind chill readings near 0 to 8 below zero.
Conditions quickly worsen Sunday evening as temperatures descend
below zero. Gusts remain throughout the evening in upwards of 25-30
mph. The higher wind speeds will make it feel extremely cold as
wind chills from 25 to 30 below zero are expected throughout the
area. A Wind Chill Warning will likely be needed in the following
forecast shift. Despite the clearing skies on Monday afternoon, the
high temperatures struggle to the single digits as. Wind chills
remain hazardous through much of Monday from 0 to 13 below zero.
Surface high pressure gradually wanes the cold air advection,
weakening and shifting surface winds towards the west by early
Monday evening. Despite the lighter winds in place, the snow cover
and clear skies will drop low temps below zero, making it feel
anywhere from 10 to 18 below zero. In terms of precipitation
chances, a much weaker embedded wave within the northwest flow aloft
quickly enters north central Kansas Sunday afternoon and evening.
Moisture is greatly limited behind the previous system, making it
difficult for any developing ice crystals to reach the surface.
There is a brief period of mid level ascent seen especially from the
recent runs of the NAM and GFS where we could see a slight chance
for snow over north central areas through Sunday evening with a few
tenths at best. Flurries are possible elsewhere on Sunday evening
with no accumulations expected.
Southerly flow returns briefly Tuesday helping temps recover back
into the 20s and low 30s. Models are still bringing another mid
level trough northward from the Baja California Wednesday afternoon
and evening. Best ascent still remains far east of Kansas with
possible light precip developing on the back edge. Temperatures
hover near and just above the freezing mark Wednesday with the
chance of a rain and snow mix during the afternoon, switching to all
snow overnight. At this time, best chances for any light accumulating
snow would be across far east central areas. A temporary dry period
sets up through Friday as temps moderate closer to normal in the
30s.
&&
.AVIATION...(For the 12Z TAFs through 12Z Sunday Morning)
Issued at 523 AM CST SAT JAN 4 2014
06Z NAM and 10Z RAP have trended the band of snow developing
further north than either the GFS or ECMWF have. This reduces
confidence in whether the terminals will have IFR conditions. Also
have little confidence in models bringing MVFR CIGS in with the
front. OBS upstream show the MVFR CIGS are quite a ways removed
from the initial wind shift. Because of this have been rather
conservative with the TAFs, holding off on the MVFR conditions
until the snow is expected to move in. Could see some IFR VSBY
overnight with the snow and gusty north winds, but trying to
figure out the location of the heavier band and most likely
timing remains a low confidence exercise.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY from 3 PM this afternoon to 9 AM CST
Sunday FOR KSZ026-039-040-054>056-058-059.
&&
$$
SHORT TERM...Wolters
LONG TERM...Bowen
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS PADUCAH KY
510 PM CST Sun Jan 5 2014
.UPDATE...
ISSUED AT 503 PM CST SUN JAN 5 2014
Updated for 00z aviation.
&&
.SHORT TERM...(This Evening through Monday)
ISSUED AT 323 PM CST SUN JAN 5 2014
Current radar Mosaic indicates temporary weakening of pcpn echoes
west of the MS river, however some enhancement is also indicated
over sern MO/swrn IL associated with the exit region of an upper
level jet.
Meanwhile, the nwrn half of the region is under very rapid cold
air advection behind a ewd-departing sfc low, and these very raw
conditions will rapidly sweep across the rest of the region during
the late afternoon. Flash freezing of water on roads is expected.
Dual Pol correlation coefficient from KVWX radar was clearly
showing the rain/snow line beginning to accelerate ewd. Any
intervals of freezing rain or sleet are expected to be even
briefer in duration than they have been up to now.
The HRRR model suggests that the aforementioned enhanced area of
snowfall over sern MO/swrn IL will fill in over most of the region
late this afternoon, except west of Poplar Bluff MO, where
snowfall will taper off rapidly to flurries by sunset.
After sunset, little measurable snowfall is forecast, but
lingering moisture in the new arctic air mass will probably
produce flurries across the entire region into part of the
overnight hours.
A secondary mid level shrtwv will produce clouds and may produce
more flurries during the day Mon. We will flirt with record lows
tonight and Mon night and will shatter minimum highs for Mon.
Dangerous wind chill readings early Mon morning will range from
-20 south to -30 north. The brisk breeze will slowly decrease during
the day. The sun will return Tue, along with "warmer" temps in the teens.
.LONG TERM...(Monday Night through Sunday)
ISSUED AT 323 PM CST SUN JAN 5 2014
Extended models are in general agreement but there are always issues
in the details.
Early Wednesday there is a broad trough over the eastern US with a
more zonal flow over the western US. By Thursday two main troughs
can be seen to our west. One over KS and OK with another off the NW
coast of the US. The first impulse is slow to get here as the
overall pattern changes to a trough in the west and more zonal flow
in the east. But we will have overrunning precipitation both
Wednesday and Thursday.
By 00Z Saturday, the GFS, GEM, and ECMWF want to carve out an upper
level low over the southwest US or Mexico. After that the speed and
intensity of the wave is in question as it moves toward us.
The initial precipitation type will be snow or freezing rain with the
GFS being the warmer model aloft and hence the chance of freezing
rain. Snowfall accumulations will be light but will have to be
monitored. Held off on any ice accumulation until the models have a
better handle on the situation. The good news is that by Friday warm
air has taken over the entire CWA and expect liquid precipitation
over the region through the weekend.
&&
.AVIATION...
ISSUED AT 503 PM CST SUN JAN 5 2014
A few more hours of IFR conditions possible for KEVV and KOWB with
MVFR elsewhere. Opted to hold onto low deck according forecast
soundings. However after 06z all sites will go high end MVFR or
VFR. Winds however will be nw and gusting up to 30 to 35 mph.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...WINTER STORM WARNING until 6 PM CST this evening FOR ILZ075>078-
080>089-092-093.
WIND CHILL ADVISORY until 9 AM CST Tuesday FOR ILZ084>094.
WIND CHILL WARNING until 9 AM CST Tuesday FOR ILZ075>078-080>083.
WINTER WEATHER ADVISORY until 6 PM CST this evening FOR ILZ090-
091-094.
MO...WINTER STORM WARNING until 6 PM CST this evening FOR MOZ076-086-
087-100-107>111.
WIND CHILL ADVISORY until 9 AM CST Tuesday FOR MOZ076-086-087-
100-107>112-114.
WINTER WEATHER ADVISORY until 6 PM CST this evening FOR MOZ112-
114.
IN...WINTER STORM WARNING until 6 PM CST this evening FOR INZ081-082-
085-086.
WIND CHILL WARNING until 9 AM CST Tuesday FOR INZ081-082-085>088.
WINTER WEATHER ADVISORY until 6 PM CST this evening FOR INZ087-
088.
KY...WIND CHILL ADVISORY until 9 AM CST Tuesday FOR KYZ001>022.
WINTER WEATHER ADVISORY until 6 PM CST this evening FOR
KYZ001>022.
&&
$$
UPDATE...KH
SHORT TERM...DB
LONG TERM...PS
AVIATION...KH
AREA FORECAST DISCUSSION
NWS GRAY ME
1038 PM EST SUN JAN 5 2014
.SYNOPSIS...
LOW PRESSURE WILL TRACK NORTH ALONG A STALLED FRONTAL BOUNDARY
WELL TO THE WEST OF THE FORECAST AREA OVERNIGHT. LOW PRESSURE WILL
CONTINUE NORTH THROUGH WESTERN QUEBEC ON MONDAY AND WILL DRIVE A
STRONG COLD FRONT THROUGH THE REGION MONDAY AFTERNOON. A STRONG
WESTERLY FLOW WILL PREVAIL BEHIND THE FRONT MONDAY NIGHT THROUGH
TUESDAY. HIGH PRESSURE WILL BUILD IN FROM THE SOUTH WEDNESDAY
THROUGH THURSDAY. A WARM FRONT WILL LIFT NORTH INTO THE FORECAST
AREA THURSDAY NIGHT AND WILL PUSH NORTHEAST OF THE REGION ON
FRIDAY. A COLD FRONT WILL PUSH THROUGH THE REGION FROM THE WEST ON
SATURDAY WITH HIGH PRESSURE TO FOLLOW ON SUNDAY.
&&
.NEAR TERM /TONIGHT/...
1030PM UPDATE...
FORECAST STILL ON TRACK WITH FREEZING RAIN NOW SPREADING INTO THE
AREA FROM THE WEST. SOME AREAS OF SLEET AND SNOW ALSO OCCURRING IN
NORTHERN AREAS... BUT THIS WILL TRANSITION TO FREEZING RAIN OVERNIGHT.
630PM UPDATE...
HAVE ADJUSTED THE FORECAST TO BETTER REFLECT TIMING OF
PRECIPITATION AS IT ENTERS THE AREA TONIGHT. THE HEAVIEST BATCH OF
PRECIPITATION IS MOVING THROUGH NEW YORK STATE LATE THIS AFTERNOON
AND WILL MOVE INTO NEW HAMPSHIRE AND NORTHWEST MAINE THIS EVENING.
STILL EXPECTING DAMMING TO BE DEEP ENOUGH TO ALLOW PRECIPITATION
TO FALL AS SNOW AND SLEET FOR A GOOD TIME PERIOD ACROSS MUCH OF
MAINE AND NORTHERN NEW HAMPSHIRE... WHILE WARM ADVECTION ALOFT
WILL BE SUFFICIENT FOR FREEZING RAIN ACROSS SOUTHERN NEW HAMPSHIRE
AND FAR SOUTHWEST MAINE. PRECIPITATION MAY BE LIGHTER AT THE COAST
AS PRECIPITATION HERE MAY BE DRIVEN MORE BY MOIST ADVECTION OFF
THE OCEAN. STILL EXPECTING TEMPERATURES TO WARM EARLY MONDAY
MORNING... CHANGING FREEZING RAIN TO RAIN. ONE POSSIBLE CONCERN IS
THAT WHILE PRECIPITATION MAY CHANGE TO RAIN WHEN AIR TEMPERATURES
RISE ABOVE FREEZING... GROUND TEMPERATURES WILL LIKELY STAY COLD
DUE TO WEEKS OF SUB FREEZING TEMPERATURES FOR MANY AREAS. THIS
COULD ALLOW RAIN TO CONTINUE TO FREEZE ON GROUND SURFACES LIKE
ROADS EVEN AFTER TEMPERATURES WARM ABOVE FREEZING.
WINTER WEATHER ADVISORIES HAVE BEEN CONVERTED TO FREEZING RAIN
ADVISORIES FOR SOUTHERN AREAS WHERE PRECIPITATION WILL BE ALMOST
ENTIRELY FREEZING RAIN. TIMING HAS ALSO BEEN EXTENDED TO ACCOUNT
FOR A POTENTIALLY SLOWER WARM UP OVERNIGHT AND MONDAY MORNING.
ORIGINAL DISCUSSION...
VERY INTERESTING SETUP WITH LOW PRESSURE PASSING WELL TO OUR WEST
OVERNIGHT. HOWEVER...AT THE SAME TIME...A WEAK AREA OF LOW
PRESSURE HAS ALREADY FORMED ALONG THE MID ATLANTIC COASTLINE. THIS
IS AHEAD OF AND TO THE NORTH OF ALL MODELED GUIDANCE AT THIS TIME.
EVEN THE MESO MODELS ARE HAVING A DIFFICULT TIME...AS THEY ARE
NOT CAPTURING THE PRECIPITATION OVER SOUTHERN NEW ENGLAND AT THE
MOMENT.
IN ANY CASE...PRECIPITATION WILL ENTER THE FORECAST AREA THIS
EVENING. HAVE LEANED TOWARDS A COLD SOLUTION...A TAD COOLER THAN
ALL AVAILABLE GUIDANCE. ATMOSPHERE STILL VERY COLD AND DRY...AND
THERE WILL BE PLENTY OF EVAPORATION COOLING AS EVIDENT ON 12Z GYX
SOUNDING.
THEREFORE...HAVE EXPANDED THE WINTER WEATHER ADVISORIES TO INCLUDE
THE COASTLINE. LATEST HRRR KEEPS TEMPERATURES BELOW FREEZING FOR
MUCH OF THE COAST THROUGH AT LEAST MIDNIGHT BEFORE THE WARM UP.
WARM UP MAY BE A TAD EARLIER AT PSM AND ALONG THE NH SEACOAST.
ENOUGH DRY AIR IN PLACE TO POSSIBLY HOLD FOR SEVERAL HOURS OF
SNOWFALL IN THE USUAL SUSPECT LOCATION OF THE FOOTHILLS. GFS
ACTUALLY PICKS UP ON THIS FEATURE.
USED A NON-DIURNAL CURVE FOR THE OVERNIGHT MINS.
HAVE SENT FORECAST SNOWFALL AND ICE MAPS. ICE WILL BE A SENSITIVE
ISSUE AS WE HAVE HAD REPORTS OF ICE STILL IN THE TREES FROM THE
ICE STORM PRIOR TO THE HOLIDAYS.
&&
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
STRONG COLD FRONT WILL CROSS THE REGION MONDAY AFTER A SIGNIFICANT
WARM UP DURING THE AFTERNOON. TEMPERATURES WILL GO FROM WELL IN THE
40S...TO A DEEP FREEZE OVER A SHORT PERIOD OF TIME. STRONGEST
WINDS WILL HOLD OFF UNTIL THE PASSAGE OF THE UPPER LEVEL TROUGH.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
MORE BITTERLY COLD ARCTIC AIR IS EXPECTED TUESDAY THRU WEDNESDAY
ON GUSTY WESTERLY WINDS WHICH WILL CREATE EXTREMELY COLD WIND
CHILLS. THE UPSLOPE WESTERLY FLOW UNDER THE UPPER LEVEL SYSTEM WILL
CREATE SCATTERED SNOW SHOWERS ACROSS THE NORTH AND MOUNTAIN ZONES.
FINALLY AS HIGH PRESSURE BUILDS IN FROM THE WEST AND THE AIR MASS
CONTINUES TO WARM WE SHOULD SEE TEMPERATURES CLIMB BACK TO MORE
NORMAL LEVELS ALONG WITH LIGHTER WINDS ON THURSDAY. LATE
THURSDAY NIGHT AND FRIDAY A WARM FRONT WITH WARM ADVECTION ALOFT
WILL MOVE ACROSS NORTHERN NEW ENGLAND CREATING SOME LIGHT SNOW
SHOWERS ON FRIDAY INTO FRIDAY EVENING. TEMPERATURES SHOULD REMAIN
COLD ENOUGH TO BE SNOW. HIGH PRESSURE AND A WARMER AIR MASS WILL
TAKE CONTROL FOR SATURDAY.
USED THE SUPERBLEND FOR TEMPERATURES AND POPS.
&&
.AVIATION /23Z SUNDAY THROUGH FRIDAY/...
SHORT TERM...CONDITIONS DETERIORATING TO IFR AND LIFR WITH FOG AND
LOW CEILINGS DEVELOPING LATER TONIGHT. CONDITIONS IMPROVE MONDAY
AFTERNOON.
LONG TERM...
MVFR IN SCATTERED SNOW SHOWERS FOR MOUNTAIN AREAS TUESDAY. GUSTY
WEST WINDS THRU TUESDAY NIGHT AND INTO WEDNESDAY. MVFR CONDITIONS
POSSIBLE FRIDAY IN SCATTERED SNOW SHOWERS.
&&
.MARINE...
SHORT TERM...HAVE ISSUED GALES FOR THE OUTER WATERS AND PENOBSCOT
BAY FOR LATE TONIGHT AND MONDAY WITH A STRONG SOUTHERLY GRADIENT.
SCA IN PLACE FOR CASCO BAY.
LONG TERM...
AN EXTENDED PERIOD OF FAIRLY STRONG WINDS AND ROUGH SEAS WITH AT
LEAST SCA CONDITIONS (AND POSSIBLY GALES OVER THE OPEN WATERS)
THRU TUESDAY NIGHT AND INTO WEDNESDAY. WINDS THEN SEAS SLOWLY EASE
UP LATE WEDNESDAY THRU THURSDAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...FREEZING RAIN ADVISORY UNTIL 6 AM EST MONDAY FOR MEZ018-023-
024.
WINTER WEATHER ADVISORY UNTIL NOON EST MONDAY FOR MEZ007>009-
013-014.
WINTER WEATHER ADVISORY UNTIL 10 AM EST MONDAY FOR MEZ012-
019>022-025>028.
NH...FREEZING RAIN ADVISORY UNTIL 6 AM EST MONDAY FOR NHZ005>010-
013-014.
WINTER WEATHER ADVISORY UNTIL NOON EST MONDAY FOR NHZ001-002.
WINTER WEATHER ADVISORY UNTIL 10 AM EST MONDAY FOR NHZ003-004.
MARINE...SMALL CRAFT ADVISORY FROM 3 AM TO 3 PM EST MONDAY FOR ANZ153.
GALE WARNING FROM 3 AM TO 3 PM EST MONDAY FOR ANZ150>152-154.
&&
$$
NEAR TERM UPDATE... KIMBLE
AREA FORECAST DISCUSSION
NWS GRAY ME
628 PM EST SUN JAN 5 2014
.SYNOPSIS...
LOW PRESSURE WILL TRACK NORTH ALONG A STALLED FRONTAL BOUNDARY
WELL TO THE WEST OF THE FORECAST AREA OVERNIGHT. LOW PRESSURE WILL
CONTINUE NORTH THROUGH WESTERN QUEBEC ON MONDAY AND WILL DRIVE A
STRONG COLD FRONT THROUGH THE REGION MONDAY AFTERNOON. A STRONG
WESTERLY FLOW WILL PREVAIL BEHIND THE FRONT MONDAY NIGHT THROUGH
TUESDAY. HIGH PRESSURE WILL BUILD IN FROM THE SOUTH WEDNESDAY
THROUGH THURSDAY. A WARM FRONT WILL LIFT NORTH INTO THE FORECAST
AREA THURSDAY NIGHT AND WILL PUSH NORTHEAST OF THE REGION ON
FRIDAY. A COLD FRONT WILL PUSH THROUGH THE REGION FROM THE WEST ON
SATURDAY WITH HIGH PRESSURE TO FOLLOW ON SUNDAY.
&&
.NEAR TERM /TONIGHT/...
630PM UPDATE...
HAVE ADJUSTED THE FORECAST TO BETTER REFLECT TIMING OF
PRECIPITATION AS IT ENTERS THE AREA TONIGHT. THE HEAVIEST BATCH OF
PRECIPITATION IS MOVING THROUGH NEW YORK STATE LATE THIS AFTERNOON
AND WILL MOVE INTO NEW HAMPSHIRE AND NORTHWEST MAINE THIS EVENING.
STILL EXPECTING DAMMING TO BE DEEP ENOUGH TO ALLOW PRECIPITATION
TO FALL AS SNOW AND SLEET FOR A GOOD TIME PERIOD ACROSS MUCH OF
MAINE AND NORTHERN NEW HAMPSHIRE... WHILE WARM ADVECTION ALOFT
WILL BE SUFFICIENT FOR FREEZING RAIN ACROSS SOUTHERN NEW HAMPSHIRE
AND FAR SOUTHWEST MAINE. PRECIPITATION MAY BE LIGHTER AT THE COAST
AS PRECIPITATION HERE MAY BE DRIVEN MORE BY MOIST ADVECTION OFF
THE OCEAN. STILL EXPECTING TEMPERATURES TO WARM EARLY MONDAY
MORNING... CHANGING FREEZING RAIN TO RAIN. ONE POSSIBLE CONCERN IS
THAT WHILE PRECIPITATION MAY CHANGE TO RAIN WHEN AIR TEMPERATURES
RISE ABOVE FREEZING... GROUND TEMPERATURES WILL LIKELY STAY COLD
DUE TO WEEKS OF SUB FREEZING TEMPERATURES FOR MANY AREAS. THIS
COULD ALLOW RAIN TO CONTINUE TO FREEZE ON GROUND SURFACES LIKE
ROADS EVEN AFTER TEMPERATURES WARM ABOVE FREEZING.
WINTER WEATHER ADVISORIES HAVE BEEN CONVERTED TO FREEZING RAIN
ADVISORIES FOR SOUTHERN AREAS WHERE PRECIPITATION WILL BE ALMOST
ENTIRELY FREEZING RAIN. TIMING HAS ALSO BEEN EXTENDED TO ACCOUNT
FOR A POTENTIALLY SLOWER WARM UP OVERNIGHT AND MONDAY MORNING.
ORIGINAL DISCUSSION...
VERY INTERESTING SETUP WITH LOW PRESSURE PASSING WELL TO OUR WEST
OVERNIGHT. HOWEVER...AT THE SAME TIME...A WEAK AREA OF LOW
PRESSURE HAS ALREADY FORMED ALONG THE MID ATLANTIC COASTLINE. THIS
IS AHEAD OF AND TO THE NORTH OF ALL MODELED GUIDANCE AT THIS TIME.
EVEN THE MESO MODELS ARE HAVING A DIFFICULT TIME...AS THEY ARE
NOT CAPTURING THE PRECIPITATION OVER SOUTHERN NEW ENGLAND AT THE
MOMENT.
IN ANY CASE...PRECIPITATION WILL ENTER THE FORECAST AREA THIS
EVENING. HAVE LEANED TOWARDS A COLD SOLUTION...A TAD COOLER THAN
ALL AVAILABLE GUIDANCE. ATMOSPHERE STILL VERY COLD AND DRY...AND
THERE WILL BE PLENTY OF EVAPORATION COOLING AS EVIDENT ON 12Z GYX
SOUNDING.
THEREFORE...HAVE EXPANDED THE WINTER WEATHER ADVISORIES TO INCLUDE
THE COASTLINE. LATEST HRRR KEEPS TEMPERATURES BELOW FREEZING FOR
MUCH OF THE COAST THROUGH AT LEAST MIDNIGHT BEFORE THE WARM UP.
WARM UP MAY BE A TAD EARLIER AT PSM AND ALONG THE NH SEACOAST.
ENOUGH DRY AIR IN PLACE TO POSSIBLY HOLD FOR SEVERAL HOURS OF
SNOWFALL IN THE USUAL SUSPECT LOCATION OF THE FOOTHILLS. GFS
ACTUALLY PICKS UP ON THIS FEATURE.
USED A NON-DIURNAL CURVE FOR THE OVERNIGHT MINS.
HAVE SENT FORECAST SNOWFALL AND ICE MAPS. ICE WILL BE A SENSITIVE
ISSUE AS WE HAVE HAD REPORTS OF ICE STILL IN THE TREES FROM THE
ICE STORM PRIOR TO THE HOLIDAYS.
&&
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
STRONG COLD FRONT WILL CROSS THE REGION MONDAY AFTER A SIGNIFICANT
WARM UP DURING THE AFTERNOON. TEMPERATURES WILL GO FROM WELL IN THE
40S...TO A DEEP FREEZE OVER A SHORT PERIOD OF TIME. STRONGEST
WINDS WILL HOLD OFF UNTIL THE PASSAGE OF THE UPPER LEVEL TROUGH.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
MORE BITTERLY COLD ARCTIC AIR IS EXPECTED TUESDAY THRU WEDNESDAY
ON GUSTY WESTERLY WINDS WHICH WILL CREATE EXTREMELY COLD WIND
CHILLS. THE UPSLOPE WESTERLY FLOW UNDER THE UPPER LEVEL SYSTEM WILL
CREATE SCATTERED SNOW SHOWERS ACROSS THE NORTH AND MOUNTAIN ZONES.
FINALLY AS HIGH PRESSURE BUILDS IN FROM THE WEST AND THE AIR MASS
CONTINUES TO WARM WE SHOULD SEE TEMPERATURES CLIMB BACK TO MORE
NORMAL LEVELS ALONG WITH LIGHTER WINDS ON THURSDAY. LATE
THURSDAY NIGHT AND FRIDAY A WARM FRONT WITH WARM ADVECTION ALOFT
WILL MOVE ACROSS NORTHERN NEW ENGLAND CREATING SOME LIGHT SNOW
SHOWERS ON FRIDAY INTO FRIDAY EVENING. TEMPERATURES SHOULD REMAIN
COLD ENOUGH TO BE SNOW. HIGH PRESSURE AND A WARMER AIR MASS WILL
TAKE CONTROL FOR SATURDAY.
USED THE SUPERBLEND FOR TEMPERATURES AND POPS.
&&
.AVIATION /23Z SUNDAY THROUGH FRIDAY/...
SHORT TERM...CONDITIONS DETERIORATING TO IFR AND LIFR WITH FOG AND
LOW CEILINGS DEVELOPING LATER TONIGHT. CONDITIONS IMPROVE MONDAY
AFTERNOON.
LONG TERM...
MVFR IN SCATTERED SNOW SHOWERS FOR MOUNTAIN AREAS TUESDAY. GUSTY
WEST WINDS THRU TUESDAY NIGHT AND INTO WEDNESDAY. MVFR CONDITIONS
POSSIBLE FRIDAY IN SCATTERED SNOW SHOWERS.
&&
.MARINE...
SHORT TERM...HAVE ISSUED GALES FOR THE OUTER WATERS AND PENOBSCOT
BAY FOR LATE TONIGHT AND MONDAY WITH A STRONG SOUTHERLY GRADIENT.
SCA IN PLACE FOR CASCO BAY.
LONG TERM...
AN EXTENDED PERIOD OF FAIRLY STRONG WINDS AND ROUGH SEAS WITH AT
LEAST SCA CONDITIONS (AND POSSIBLY GALES OVER THE OPEN WATERS)
THRU TUESDAY NIGHT AND INTO WEDNESDAY. WINDS THEN SEAS SLOWLY EASE
UP LATE WEDNESDAY THRU THURSDAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...FREEZING RAIN ADVISORY UNTIL 6 AM EST MONDAY FOR MEZ018-023-
024.
WINTER WEATHER ADVISORY UNTIL NOON EST MONDAY FOR MEZ007>009-
013-014.
WINTER WEATHER ADVISORY UNTIL 10 AM EST MONDAY FOR MEZ012-
019>022-025>028.
NH...FREEZING RAIN ADVISORY UNTIL 6 AM EST MONDAY FOR NHZ005>010-
013-014.
WINTER WEATHER ADVISORY UNTIL NOON EST MONDAY FOR NHZ001-002.
WINTER WEATHER ADVISORY UNTIL 10 AM EST MONDAY FOR NHZ003-004.
MARINE...SMALL CRAFT ADVISORY FROM 3 AM TO 3 PM EST MONDAY FOR ANZ153.
GALE WARNING FROM 3 AM TO 3 PM EST MONDAY FOR ANZ150>152-154.
&&
$$
NEAR TERM UPDATE... KIMBLE
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
848 PM EST SUN JAN 5 2014
.SYNOPSIS...
A STRONG COLD FRONT WILL CROSS THE REGION LATE TONIGHT THROUGH
MONDAY MORNING...FOLLOWED BY A VERY COLD ARCTIC AIRMASS FOR MONDAY
AFTERNOON INTO MID-WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
SFC LO PRES IS TRACKING NE INVOF OH VLY...W/ A TRAILING CDFNT INTO
THE WRN GULF OF MEXICO. MEANWHILE...A FNTL BNDRY IS ALIGNED FM SRN NJ
SW TO CNTRL GA...SEPARATING LO LVL CAD (W) FM MUCH WARMER AIR ALG
THE CSTL PLAIN. QUITE THE TEMP GRADIENT (@7 PM)...36 AT LKU...39
AT FVX...55 AT RIC...62 AT AKQ...61 AT ORF.
LIGHT PRECIPITATION HAS DEVELOPED ALONG THE COAST THIS EVENING.
THIS IS WELL DEPICTED ON THE CURRENT RAP MODEL AND SHOULD BE
OFFSHORE BY 03Z. RAISED POPS SOME SE DUE TO THIS RAIN AREA. SPOTTY
VERY LGT RA CONTG TO MOVE OVR (MNLY INLAND) AREAS OF FA THIS
EVENING...WILL LIKELY BE A LULL IN PCPN FOR A TIME OVRNGT AHEAD OF
THE APPROACHING CDFNT. BY LT TNGT...XPCG AN AREA OF RA TO REACH AT
LEAST AREAS FM I 95 ON W. OTRW...RMNG MCLDY ACRS THE FA THROUGH
THE NGT. NOT XPCG THE BNDRY DRAPED OVR FAR WRN AREAS TO BUDGE MUCH
OVRNGT...SO TEMPS NR/W OF THAT BNDRY OVR THE PIEDMONT (WELL WNW OF
RIC) WILL HOLD FM THE U30S TO L40S...WHILE A MILD NGT XPCD ELSW W/
TEMPS (EVENTUALLY) MNLY IN THE 50S.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/...
SFC LO PRES TRACKS NE THROUGH THE ST LAWRENCE RVR VLY ON MON...W/
ITS TRAILING CDFNT PLOWING EWD ACRS THE FA BY AFTN. STARTING OUT
THE DAY MILD/CLOUDY W/ SCT SHRAS IN MOST PLACES BEFORE STRONG LO LVL
CAA ON GUSTY WNW WNDS (TO 30-35 MPH) TAKES OVR FM MID/LT MRNG
THROUGH THE AFTN. WILL BE CONTG IDEA OF TAPERING/ENDING POPS FM
W-E FM 15Z- 21Z/06 ALG W/ CLEARING. TEMPS STARTING OUT (AT LEAST)
IN THE 50S E AND CNTRL...40S W...THEN DROPPING THROUGHOUT THE DAY
DESPITE RETURN OF SUNSHINE.
STRONG LO LVL CAA CONTS MON NGT INTO TUE ALG W/ GUSTY WNW WNDS.
DESPITE NO SNOW COVER...QUITE THE IMPRESSIVELY COLD AIRMASS TO BE
OVR THE RGN (POTENTIALLY RIVALING ONES IN FEB 1996/JAN 1994).
TEMPS FALLING INTO THE SINGLE DIGITS AND TEENS ACRS MOST OF THE
RGN...COMBINED W/ THE GUSTY WNDS MNLY TO 25-35 MPH WILL LIKELY
RESULT IN WIND CHILLS LWRG TO +5F TO -5F ERN THIRD TO -5F TO -10F
ALG/W OF I 95 IN VA/ACRS PORTIONS OF THE LWR MD ERN SHORE. WILL
CONT MENTION OF THESE WIND CHILL VALUES IN THE HWO...W/
ANTICIPATION OF AN ADVISORY ISSUANCE OVRNGT.
VERY COLD AIR RMNS FIRMLY IN PLACE TUE AS STRONG SFC HI PRES
(APPROX 1036 MB) FM THE W IS SLO TO BUILD TOWARD THE FA. DESPITE
PLENTY OF SUNSHINE...HI TEMPS XPCD TO ONLY REACH THE UPR TEENS AND
L20S MOST PLACES. THE WORST OF THE LO WIND CHILL VALUES XPCD TO BE
LIMITED TO THE MRNG HRS.
COLD AND DRY WX TUE NGT AND WED W/ HI PRES IN CONTROL. LO TEMPS
AGN TUE NGT FM THE SINGLE DIGITS TO TEENS IN MOST PLACES...W/ HI
TEMPS ON WED FM THE L/M30S N...TO M/U30S S.
NOTE: SEE CLIMATE SECTION BELOW FOR RECORD LOW TEMPS TUE/WED...AND
RECORD LOW HIGH TEMPS TUE.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A SHORTWAVE FEATURE MOVING OUT OF THE INTERMOUNTAIN WEST AND INTO
THE SRN PLAINS WED NIGHT WILL CREATE JUST ENOUGH OF A TROUGH TO
SHIFT THE ARCTIC HIGH PRESSURE TO THE NORTHEAST...AND JUST OUT OF
THE AREA...ON WEDNESDAY NIGHT. CONDITIONS WILL REMAIN DRY AND
STABLE SO OVERNIGHT LOWS SHOULD HAVE NO PROBLEM DROPPING INTO THE
20S AREAWIDE WEDNESDAY NIGHT. SW FLOW DEVELOPS ON THURSDAY AND
WILL ALLOW HIGH TEMPS WARM TWD MORE SEASONAL VALUES. EXPECT HIGHS
IN THE MID-UPPER 40S MOST AREAS WITH HIGHS AROUND 50 OVER FAR SE
VA AND NE NC. THE AFOREMENTIONED SRN PLAINS SHORTWAVE APPROACHES
FORM THE WEST THURSDAY...AND TRAVERSES ACROSS THE MID ATLANTIC
REGION THURSDAY NIGHT INTO FRIDAY AFTERNOON. SURFACE TEMPERATURES
SHOULD RISE ABOVE 32 F ACROSS THE ENTIRE LOCAL AREA BY THE TIME
ANY LIGHT PRECIP ARRIVES...SO ALL PRECIP IS STILL EXPECTED TO BE
RAIN. MID AND UPPER LEVEL RIDGING IS ANTICIPATED TO PASS OVERHEAD
FRI NIGHT...BUT WILL BE SHORT-LIVED AS PERIODS OF ADDITIONAL
SHORTWAVE ENERGY/MOISTURE CROSS THE MID ATLANTIC REGION THROUGH
THE WEEKEND AS ANOTHER LONGWAVE TROUGH DIGS OVER THE CENTRAL
CONUS DURING THIS TIME.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
AS OF 01Z...ALL THE TAF SITES WERE IN THE WARM SECTOR OF THE COASTAL
FRONT THAT WAS ALIGNED NORTHEAST TO SOUTHWEST ACROSS THE MID
ATLANTIC STATES. THIS SHOULD REMAIN THE CASE AS THE COLD FRONT OVER
THE OHIO VALLEY RUSHES QUICKLY TO THE EAST. WINDS INCREASE FROM THE
SOUTH OVERNIGHT BEFORE SHIFTING TO THE SW AND FINALLY TO THE W/NW
BEHIND THE FRONT. AT THAT TIME...AROUND 14-17Z...WINDS INCREASE TO
AROUND 15-25 KNOTS WITH HIGHER GUSTS.
AT 23Z...CONDITIONS WERE MAINLY VFR WITH SOME OCNL MVFR IN AND
AROUND THE TAF SITES. IFR WAS CONFINED TO THE COLD AIR SIDE OF THE
FRONT OVER THE PIEDMONT. SINCE THEN...MOISTURE HAS INCREASED ENOUGH
TO RESULT IN SOME PATCHY IFR. THIS IS NOT EXPECTED TO BE THE RULE
AND PREDOMINATE MVFR CONTINUES IN THE FORECAST. THIS WILL NEED TO BE
MONITORED. CEILINGS SHOULD IMPROVE FOLLOWING THE FRONTAL PASSAGE.
FOLLOWED CLOSE TO THE LAVMOS WHICH HAS CIGS IMPROVING TO VFR FAIRLY
QUICKLY CONSIDERING THE DOWNSLOPING EFFECT ON DRYING. THIS WOULD BE
FOLLOWED BY MOSTLY CLEAR SKIES IN THE LATE AFTN. THE NAM IS SLOWER
WITH SCOURING OUT THE LOW LEVEL MOISTURE.
OUTLOOK...GUSTY NW WINDS WILL BE THE MAIN STORY FOR MONDAY NIGHT AND
TUESDAY MORNING. THOSE WINDS BEGIN TO DIMINISH DURING THE DAY
TUESDAY AND ESPECIALLY BY TUESDAY NIGHT. DRY WITH VFR CONDITIONS IS
EXPECTED WEDNESDAY THROUGH THURSDAY. THERE WILL BE A CHC FOR PCPN
THURSDAY NIGHT AND FRIDAY.
&&
.MARINE...
THERE ARE TWO WEATHER FEATURES TO KEEP AN EYE ON THIS EVENING. THE
FIRST SYSTEM IS A DEVELOPING COASTAL LOW THAT IS CURRENTLY LOCATED
ALONG THE SC COAST. THIS SYSTEM WILL MOVE NWD ALONG THE CAROLINA
COAST AND THROUGH THE MID ATLANTIC REGION TONIGHT...SPREADING
RAINFALL OVER THE WATERS. SE WINDS WILL INCREASE THROUGH THE
EVENING AS THE COASTAL LOW DEEPENS AS IT APPROACHES THE WATERS.
EXPECT WIND SPEEDS OF GENERALLY 15-25 KT FOR COASTAL WATERS AND
10-15 KT BAY/RIVERS/SOUND. SEAS FROM THE VA/NC BORDER TO CURRITUCK
LIGHT HAVE FALLEN TO 4 FT BUT SHOULD RISE BACK UP TO 5 FT RATHER
QUICKLY THIS EVENING AS SE WINDS INCREASE. THE SE WIND DIRECTION
MAY ALSO CAUSE 4 FT WAVES TO FILTER INTO THE CTRL MOUTH OF CHES
BAY THIS EVENING...OTHERWISE WAVES SHOULD AVERAGE 2-3 FT TONIGHT.
THE NEXT FEATURE TO WATCH CAREFULLY IS A VERY STRONG ARCTIC COLD
FRONT THAT IS STILL EXPECTED TO CROSS THE WATERS MON MORNING
THROUGH AFTN. THE COLD FRONT WILL RAPIDLY STRENGTHEN TONIGHT INTO
MON MORNING AS IT MOVES FROM THE OH/TN VALLEYS INTO THE ERN GREAT
LAKES. S WINDS OF ROUGHLY 20-30 KT MON MORNING WILL QUICKLY VEER
TO THE NW BEHIND THE VIGOROUS FRONTAL PASSAGE. EXTREMELY TIGHT
TEMPERATURE AND PRESSURE GRADIENTS BEHIND THE FRONT WILL CAUSE
WINDS TO RAPIDLY INCREASE TO 25-35 KT WITH GUSTS UP TO 40 KT OVER
CHES BAY AND THE COASTAL WATERS...LIKELY BEGINNING BY LATE MON
MORNING. WAVES/SEAS WILL RESPOND QUICKLY TO THE RAPID INCREASE IN
WIND SPEEDS...WITH WAVES BUILDING TO 4-6 FT ON CHES BAY AND SEAS
BUILDING TO 5-8 FT ALL COASTAL WATERS. GALE FORCE GUSTS (AND WINDS
OVERALL) ARE ANTICIPATED TO INTENSIFY MON NIGHT AS THE VERY COLD
ARCTIC AIRMASS BLASTS OVER THE WATERS. MODEL GUIDANCE IS
DRASTICALLY UNDERCUTTING THE WIND POTENTIAL OVER THE WATERS AND
HAVE GONE AT LEAST 10 KT ABOVE THE STRONGEST MODEL(S). EVEN BY
DOING THIS...CURRITUCK SOUND AND THE ERN VA RIVERS STAY WITHIN
STRONG SCA CONDITIONS. IN REGARD TO THE GALES...THERE IS A LEVEL
OF UNCERTAINTY AS TO WHEN THEY SHOULD SUBSIDE AND ARE THEN
FOLLOWED BY STRONG SCA CONDITIONS. MAIN CONCERN IS THAT THE STRONG
CAA OVER LAND AND WATER SURFACES EARLY MON NIGHT WILL START TO
EQUALIZE FASTER THAN ANTICIPATED LATE MON NIGHT/EARLY TUE MORNING.
HOWEVER...THE MUCH COLDER AIR TEMPS OVER THE WARMER WATERS SHOULD
BE ENOUGH TO ERASE THIS UNCERTAINTY. HAVE DECIDED TO ISSUE A GALE
WARNING TONIGHT THROUGH EARLY TUE MORNING FOR CHES BAY AND COASTAL
WATERS FROM FENWICK ISLAND TO CURRITUCK LIGHT FOR THE ADVERSE
CONDITIONS EXPECTED. IF THE AIR/WATER TEMPERATURE DIFFERENCES
RESULT IN STRONGER WINDS MON NIGHT...THEN GALE HEADLINES MAY NEED
TO BE EXTENDED THROUGH EARLY TUE AFTN (WILL MONITOR CLOSELY).
W WINDS REMAIN STRONG THROUGH TUE. AS HIGH PRESSURE BUILDS INTO
THE REGION FROM THE WEST LATE IN THE DAY...THE TEMP/PRESSURE
GRADIENTS BEGIN TO RELAX...THUS ALLOWING WINDS TO SLOWLY DIMINISH
THROUGH TUE EVENING. SEAS SHOULD FOLLOW THE SAME TREND DURING THIS
TIME BUT SHOULD NOT FALL BELOW 5 FT UNTIL CLOSER TO WED MORNING.
HIGH PRESSURE CROSSES THE WATERS WED/THU WITH MORE BENIGN
CONDITIONS EXPECTED. THE NEXT LOW PRESSURE SYSTEM TO IMPACT THE
MID ATLANTIC REGION IS EXPECTED TO CROSS THE WATERS THU NIGHT INTO
EARLY FRI.
&&
.TIDES/COASTAL FLOODING...
TIDES WILL RUN ABOUT 0.5 FEET ABOVE NORMAL DURING THE NEXT TWO HIGH
TIDE CYCLES (OR THROUGH MONDAY MORNING`S HIGH TIDE)...HOWEVER
WATER LEVELS ARE EXPECTED TO REMAIN WELL BELOW ANY MINOR FLOODING
THRESHOLDS. TIDES ARE ON TREND TO FALL 0.5 TO 1.0 FEET BELOW
NORMAL BEHIND THE STRONG ARCTIC FRONTAL PASSAGE MONDAY MORNING.
BLOWOUT TIDES MAY BE POSSIBLE ALONG WESTERN PORTIONS OF
CHESAPEAKE BAY AND THE ATLANTIC OCEAN NEAR OCEAN CITY BY THE
SECOND LOW TIDE CYCLE ON TUESDAY.
&&
.CLIMATE...
VERY COLD WEATHER IS EXPECTED FROM MON NGT INTO WED...
RECORD LOW TEMP TUE JAN 7:
RIC 12/1988
ORF 13/1884
SBY 7/1919
ECG 15/1959
WAL 12/1988
RECORD LOW HIGH TEMP TUE JAN 7:
RIC 21/1996
ORF 28/1878
SBY 24/1988
ECG 32/1988
WAL 28/1973
RECORD LOW TEMP WED JAN 8:
RIC -8/1942
ORF 13/1970
SBY -4/1912
ECG 16/1968
WAL 14/1970
THE LAST TIME THE HIGH TEMP DIDN`T REACH 20 DEGREES F:
RIC 18 DEG F 2/4/1996 (SNOW DEPTH 2 INCHES)
ORF 13 DEG F 1/19/1994 (SNOW DEPTH TRACE)
SBY 18 DEG F 1/10/2004 (SNOW DEPTH 0)
ECG 16 DEG F 1/21/1985
WAL 19 DEG F 2/4/1996 (SNOW DEPTH 7 INCHES)
THE LAST TIME WIND CHILLS WERE BELOW ZERO:
RIC 12/20/2004
ORF 12/20/2004
SBY 1/22/2011
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST TUESDAY FOR ANZ633-635>638.
GALE WARNING UNTIL 7 AM EST TUESDAY FOR ANZ630>632-634-650-652-
654-656-658.
&&
$$
SYNOPSIS...ALB
NEAR TERM...ALB/JAB
SHORT TERM...ALB
LONG TERM...BMD
AVIATION...LSA
MARINE...BMD
TIDES/COASTAL FLOODING...
CLIMATE...
AREA FORECAST DISCUSSION...UPDATED
NWS BALTIMORE MD/WASHINGTON DC
722 PM EST SUN JAN 5 2014
.SYNOPSIS...
LOW PRESSURE WILL TRACK NORTHEAST UP THE EASTERN OHIO RIVER VALLEY
THIS EVENING. A STRONG COLD FRONT WILL MOVE THROUGH THE AREA
EARLY MONDAY MORNING. ARCTIC HIGH PRESSURE WILL THEN BUILD THROUGH
TUESDAY NIGHT BEFORE DRIFTING OFFSHORE. A WEAK FRONT IS EXPECTED
TO CROSS THE AREA THURSDAY NIGHT INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
HEADLINE UPDATE...MODIFIED FREEZING RAIN WRNG/ADZY FOR THE LATE
EVE HRS. MOST OF THE PREV HEADLINES HAVE BEEN EXTENDED TIL
MIDNIGHT...W/ A COUPLE OF FRINGE ZONES EXPIRING AT 9 PM. SEE
WBCWSWLWX FOR DETAILS.
PUSHED THE START TIME FOR THE SMALL CRAFT ADZY TO 9 PM...W/ WINDS
OVER BAY STILL LIGHT AND THE LOW LEVELS STILL STABLE ENOUGH TO
PREVENT SUBSTANTIAL MIXING OF THE HIGH BOUNDARY LAYER WINDS. THIS
WILL LIKELY CHANGE LATER TONIGHT AS THE STRONG COLD FRONT
APPROACHES FROM THE WEST AND THE REGIONAL-SCALE DYNAMICS BEGIN TO
ERODE THE STABLE LAYER.
FROM PREV DISC...
TEMPS SHOULD SLOWLY RISE ABOVE FREEZING LATE THIS EVENING ACROSS
THE CWA - EXCEPT OVER THE POTOMAC HIGHLANDS...WRN POTOMAC RVR VLY.
THE COMBINATION OF WARM AND MOIST AIR OVER THE COLD GROUND AND
SNOWPACK MAY RESULT IN AREAS OF DENSE FOG. MONITORING THE DENSE
FOG POTENTIAL WHICH LOOKS LIKE IT MAY BE MORE LIMITED TO THE
MASON-DIXON LINE REGION AND THE NRN BALT AREA SUBURBS TO THE PA
LINE. HI-RES LOCAL GUIDANCE LIKE THE WRF AND HRRR SHOWING THIS
KIND OF DEPICTION.
TEMPS WILL GENERALLY RISE INTO THE 40S EVERYWHERE EXCEPT AROUND
HAGERSTOWN WHERE THE WEDGE ERODES LAST. ALSO...LOW TO 50S ARE
EXPECTED IN SRN MD.
THE LOW WILL RAPIDLY MOVE INTO CENTRAL CANADA LATE TONIGHT AND THE
ARCTIC COLD FRONT ASSOCIATED WITH THE LOW IS EXPECTED TO MOVE INTO
THE AREA TOWARD MONDAY MORNING. MUCH COLDER AIR WILL MOVE INTO
POTOMAC HIGHLANDS BEHIND THE FRONT TOWARD MONDAY MORNING...CAUSING
RAIN TO CHANGE TO SNOW. SNOW ACCUMULATION IS EXPECTED...ESPECIALLY
NEAR AND WEST OF THE ALLEGHENY FRONT.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY/...
ARCTIC COLD FRONT STILL ON TRACK TO MOVE ACROSS THE INTERSTATE 95
CORRIDOR BY 10Z MONDAY AND THEN THE CHESAPEAKE BAY BY 12Z. COLDER
AIR WILL QUICKLY RUSH IN BEHIND THE FRONT. NON-DIURNAL FROM LATE
TONIGHT THROUGH MONDAY NIGHT TO REFLECT FALLING TEMPERATURES
BEHIND THE FRONT.
RAIN WILL CONTINUE OVER NIGHT...ENDING AS SNOW WITH THE COLD
FRONT. MOST OF THE ACCUMULATING SNOW STILL APPEARS TO BE
RELEGATED TO THE POTOMAC HIGHLANDS WHERE AMOUNTS SHOULD BE AROUND
2 INCHES. ONLY TRACE TO A COUPLE TENTHS AT LOWER ELEVATIONS EAST
OF THERE TO THE BAY.
HAZARDOUS IMPACT THEN SHIFTS TO THE BITTERLY COLD AIR MASS
PLUNGING INTO THE AREA...LIKELY THE COLDEST IN 20 YEARS. WEST TO
NORTHWEST WINDS OF 20 TO 25 MPH WITH GUSTS OF 30 TO 40 MPH WILL
BEGIN MONDAY MORNING. WITH THE AMBIENT TEMP DROPPING...WIND CHILLS
WILL DROP...BUT NOT BE DANGEROUS ACROSS THE AREA UNTIL THE LATE
AFTERNOON (WIND CHILLS ARE EXPECTED TO DROP BELOW MINUS 5 AROUND
MIDDAY FOR THE ALLEGHENY HIGHLANDS. THAT TIME WILL SERVE WELL TO
BEGIN THE WIND CHILL WARNING. MOST DANGEROUS PERIOD FOR WIND
CHILLS WILL BE MONDAY EVENING THROUGH MIDDAY TUESDAY AS WINDS ARE
NOT EXPECTED TO DIMINISH UNTIL LATE TUESDAY. THE WIND CHILL WATCH
WILL BE UPGRADED TO A WARNING FOR ALL OF THE WATCH AREA AND
PROBABLY FOR N-CNTRL MD WHERE MINUS 20 TO MINUS 25 WILL BE COMMON
(WIND CHILLS OF MINUS 30 TO EVEN MINUS 40 POSSIBLE ALONG
RIDGELINES). EAST OF THE BLUE RIDGE...EXPECT WIND CHILLS OF MINUS
5 TO MINUS 20.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
THE MAIN STORY OF THE LONG RANGE IS MODERATING TEMPERATURES. ABOVE
CLIMO NORMS ARE EXPECTED BY THE END OF THE WEEK. ENOUGH COLD AIR MAY
STILL BE IN PLACE HOWEVER FOR SOME SNOW THURSDAY NIGHT.
OTHERWISE...ANY PRECIPITATION ASSOCIATED WITH A SERIES OF TROUGHS
MOVING THROUGH THE REGION WILL BE IN THE FORM OF RAIN.
HIGH PRESSURE OVERHEAD WILL BRING ANOTHER COLD MORNING WEDNESDAY BUT
THERE WILL BE LESS WIND SO IT SHOULDN/T FEEL AS HARSH AS TUESDAY
MORNING. HIGH PRESSURE MOVES OFF THE COAST DURING THE DAY
WEDNESDAY...AND THIS WILL PROMOTE A MODERATING TREND THROUGH THE END
OF THE WEEK AND THIS MAY CONTINUE INTO THE WEEKEND.
MODELS SHOW ONE DISTURBANCE BRINGING A CHANCE OF PRECIP TOWARD THE
END OF THE WEEK. THERE STILL MAY BE ENOUGH COLD AIR IN PLACE FOR
WINTRY PRECIP THURSDAY NIGHT IF MOISTURE ARRIVES BY THAT TIME...BUT
THIS WOULD LIKELY BECOME RAIN FOR FRIDAY. THERE MAY BE ANOTHER WAVE
OVER THE WEEKEND...BUT UNCERTAINTY IS HIGH THIS FAR OUT.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
CIGS/VSBYS WILL CONTINUE TO DETERIORATE WITH IFR CONDITIONS
WORSENING THIS AFTERNOON. LIFR CONDITIONS STILL POSSIBLE INTO THE
EARLY MRNG HRS...TOWARD 6Z BUT WILL GRADUALLY MIX OUT TOWARD DAWN.
KMRB...FREEZING RAIN WILL LIKELY CONTINUE INTO THE EVENING.
STRONG COLD FRONT MOVES THROUGH EARLY MONDAY MORNING...USHERING IN
GUSTY WEST WINDS BEHIND IT. EXPECT RAIN TO CHANGE TO A BRIEF
PERIOD OF SNOW BEFORE ENDING MONDAY MORNING. WIND WILL BE THE
MAIN IMPACT INTO TUESDAY WITH W/NW WINDS AROUND 20 KT WITH GUSTS
AROUND 30 KT. 35 TO 40 KT GUSTS POSSIBLE MONDAY NIGHT. HIGH
PRESSURE BUILDS IN TUESDAY NIGHT WITH LIGHT SOUTH WINDS THEN
WEDNESDAY AND THURSDAY.
&&
.MARINE...
SOUTHERLY WINDS WILL INCREASE AS A COLD FRONT APPROACHES THE WATERS
TONIGHT. A SMALL CRAFT ADVISORY IS IN EFFECT FOR THE MARYLAND
CHESAPEAKE BAY AND LOWER TIDAL POTOMAC RIVER.
COLD FRONT MOVES ACROSS THE BAY EARLY IN THE MORNING MONDAY. WINDS
SHIFT TO THE WEST AND INCREASE DURING THE DAYTIME...AND BE UP TO 30
KT GUSTS BY THE EARLY AFTERNOON. GALE WARNING BEGINS MONDAY
EVENING...BUT MAY START LATE AFTERNOON MONDAY. GALES MAY CONTINUE
INTO TUESDAY...WITH SCA WINDS INTO TUESDAY EVENING FOR AT LEAST
PORTIONS OF THE WATERS.
TRANQUIL CONDITIONS TUESDAY NIGHT UNDER HIGH PRESSURE...THE SLY
FLOW THROUGH THURSDAY NIGHT AHEAD OF A COLD FRONT.
&&
.CLIMATE...
RECORD MINIMUM AND LOW MAXIMUM TEMPERATURES ARE LIKELY ACROSS THE
BALTIMORE-WASHINGTON METRO AREA MONDAY NIGHT AND EXPECTED FOR TUESDAY.
IT WILL REMAIN COLD TUESDAY NIGHT...BUT LIKELY NOT REACH RECORD
MINIMUMS.
RECORD MIN TEMPS FOR JAN 7...
DC...5 DEGREES IN 1884
BALTIMORE...8 DEGREES IN 1988
DULLES....8 DEGREES IN 1988
RECORD LOW MAX TEMPS FOR JAN 7...
DC...18 DEGREES IN 1878
BALTIMORE...22 DEGREES IN 1878 / 1988 / 1996
DULLES....21 DEGREES IN 1988 / 1996
RECORD MIN TEMPS FOR JAN 8...
DC...0 DEGREES IN 1878
BALTIMORE...4 DEGREES IN 1970
DULLES....-4 DEGREES IN 1970
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...FREEZING RAIN ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR MDZ501-
502.
WIND CHILL WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING
FOR MDZ501-502.
WIND CHILL WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING
FOR MDZ003.
ICE STORM WARNING UNTIL MIDNIGHT EST TONIGHT FOR MDZ003-004.
ICE STORM WARNING UNTIL 9 PM EST THIS EVENING FOR MDZ005.
VA...FREEZING RAIN ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR VAZ028.
WIND CHILL WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING
FOR VAZ503-504.
WIND CHILL WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING
FOR VAZ025>031.
FREEZING RAIN ADVISORY UNTIL 9 PM EST THIS EVENING FOR VAZ027-
030-501.
ICE STORM WARNING UNTIL MIDNIGHT EST TONIGHT FOR VAZ031-042.
WV...FREEZING RAIN ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR
WVZ050>052-503-504.
WIND CHILL WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING
FOR WVZ501>506.
WIND CHILL WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING
FOR WVZ050>053-055.
ICE STORM WARNING UNTIL MIDNIGHT EST TONIGHT FOR WVZ053.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST MONDAY FOR ANZ530>534-
537>543.
GALE WARNING FROM 6 PM MONDAY TO 6 AM EST TUESDAY FOR
ANZ530>543.
SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EST MONDAY FOR ANZ535-
536.
&&
$$
UPDATE...GMS/JRK
PREV DISCUSSION...BJL/DFH/BAJ
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
706 PM EST SUN JAN 5 2014
.SYNOPSIS...
A STRONG COLD FRONT WILL CROSS THE REGION LATE TONIGHT THROUGH
MONDAY MORNING...FOLLOWED BY A VERY COLD ARCTIC AIRMASS FOR MONDAY
AFTERNOON INTO MID-WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
SFC LO PRES IS TRACKING NE INVOF OH VLY...W/ A TRAILING CDFNT INTO
THE WRN GULF OF MEXICO. MEANWHILE...A FNTL BNDRY IS ALIGNED FM SRN NJ
SW TO CNTRL GA...SEPARATING LO LVL CAD (W) FM MUCH WARMER AIR ALG
THE CSTL PLAIN. QUITE THE TEMP GRADIENT (@7 PM)...36 AT LKU...39
AT FVX...55 AT RIC...62 AT AKQ...61 AT ORF.
LIGHT PRECIPITATION HAS DEVELOPED ALONG THE COAST THIS EVENING.
THIS IS WELL DEPICTED ON THE CURRENT RAP MODEL AND SHOULD BE
OFFSHORE BY 03Z. RAISED POPS SOME SE DUE TO THIS RAIN AREA. SPOTTY
VERY LGT RA CONTG TO MOVE OVR (MNLY INLAND) AREAS OF FA THIS
EVENING...WILL LIKELY BE A LULL IN PCPN FOR A TIME OVRNGT AHEAD OF
THE APPROACHING CDFNT. BY LT TNGT...XPCG AN AREA OF RA TO REACH AT
LEAST AREAS FM I 95 ON W. OTRW...RMNG MCLDY ACRS THE FA THROUGH
THE NGT. NOT XPCG THE BNDRY DRAPED OVR FAR WRN AREAS TO BUDGE MUCH
OVRNGT...SO TEMPS NR/W OF THAT BNDRY OVR THE PIEDMONT (WELL WNW OF
RIC) WILL HOLD FM THE U30S TO L40S...WHILE A MILD NGT XPCD ELSW W/
TEMPS (EVENTUALLY) MNLY IN THE 50S.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/...
SFC LO PRES TRACKS NE THROUGH THE ST LAWRENCE RVR VLY ON MON...W/
ITS TRAILING CDFNT PLOWING EWD ACRS THE FA BY AFTN. STARTING OUT
THE DAY MILD/CLOUDY W/ SCT SHRAS IN MOST PLACES BEFORE STRONG LO LVL
CAA ON GUSTY WNW WNDS (TO 30-35 MPH) TAKES OVR FM MID/LT MRNG
THROUGH THE AFTN. WILL BE CONTG IDEA OF TAPERING/ENDING POPS FM
W-E FM 15Z- 21Z/06 ALG W/ CLEARING. TEMPS STARTING OUT (AT LEAST)
IN THE 50S E AND CNTRL...40S W...THEN DROPPING THROUGHOUT THE DAY
DESPITE RETURN OF SUNSHINE.
STRONG LO LVL CAA CONTS MON NGT INTO TUE ALG W/ GUSTY WNW WNDS.
DESPITE NO SNOW COVER...QUITE THE IMPRESSIVELY COLD AIRMASS TO BE
OVR THE RGN (POTENTIALLY RIVALING ONES IN FEB 1996/JAN 1994).
TEMPS FALLING INTO THE SINGLE DIGITS AND TEENS ACRS MOST OF THE
RGN...COMBINED W/ THE GUSTY WNDS MNLY TO 25-35 MPH WILL LIKELY
RESULT IN WIND CHILLS LWRG TO +5F TO -5F ERN THIRD TO -5F TO -10F
ALG/W OF I 95 IN VA/ACRS PORTIONS OF THE LWR MD ERN SHORE. WILL
CONT MENTION OF THESE WIND CHILL VALUES IN THE HWO...W/
ANTICIPATION OF AN ADVISORY ISSUANCE OVRNGT.
VERY COLD AIR RMNS FIRMLY IN PLACE TUE AS STRONG SFC HI PRES
(APPROX 1036 MB) FM THE W IS SLO TO BUILD TOWARD THE FA. DESPITE
PLENTY OF SUNSHINE...HI TEMPS XPCD TO ONLY REACH THE UPR TEENS AND
L20S MOST PLACES. THE WORST OF THE LO WIND CHILL VALUES XPCD TO BE
LIMITED TO THE MRNG HRS.
COLD AND DRY WX TUE NGT AND WED W/ HI PRES IN CONTROL. LO TEMPS
AGN TUE NGT FM THE SINGLE DIGITS TO TEENS IN MOST PLACES...W/ HI
TEMPS ON WED FM THE L/M30S N...TO M/U30S S.
NOTE: SEE CLIMATE SECTION BELOW FOR RECORD LOW TEMPS TUE/WED...AND
RECORD LOW HIGH TEMPS TUE.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A SHORTWAVE FEATURE MOVING OUT OF THE INTERMOUNTAIN WEST AND INTO
THE SRN PLAINS WED NIGHT WILL CREATE JUST ENOUGH OF A TROUGH TO
SHIFT THE ARCTIC HIGH PRESSURE TO THE NORTHEAST...AND JUST OUT OF
THE AREA...ON WEDNESDAY NIGHT. CONDITIONS WILL REMAIN DRY AND
STABLE SO OVERNIGHT LOWS SHOULD HAVE NO PROBLEM DROPPING INTO THE
20S AREAWIDE WEDNESDAY NIGHT. SW FLOW DEVELOPS ON THURSDAY AND
WILL ALLOW HIGH TEMPS WARM TWD MORE SEASONAL VALUES. EXPECT HIGHS
IN THE MID-UPPER 40S MOST AREAS WITH HIGHS AROUND 50 OVER FAR SE
VA AND NE NC. THE AFOREMENTIONED SRN PLAINS SHORTWAVE APPROACHES
FORM THE WEST THURSDAY...AND TRAVERSES ACROSS THE MID ATLANTIC
REGION THURSDAY NIGHT INTO FRIDAY AFTERNOON. SURFACE TEMPERATURES
SHOULD RISE ABOVE 32 F ACROSS THE ENTIRE LOCAL AREA BY THE TIME
ANY LIGHT PRECIP ARRIVES...SO ALL PRECIP IS STILL EXPECTED TO BE
RAIN. MID AND UPPER LEVEL RIDGING IS ANTICIPATED TO PASS OVERHEAD
FRI NIGHT...BUT WILL BE SHORT-LIVED AS PERIODS OF ADDITIONAL
SHORTWAVE ENERGY/MOISTURE CROSS THE MID ATLANTIC REGION THROUGH
THE WEEKEND AS ANOTHER LONGWAVE TROUGH DIGS OVER THE CENTRAL
CONUS DURING THIS TIME.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
STILL MOSTLY VFR CIGS AND VSBY ACROSS THE REGION BUT LOW LEVEL
MOISTURE AND CHC FOR -RA EXPECTED TO INCREASE THRU THE
AFTN/EVENING. RAIN IS STILL WIDELY SCATTERED AND CONTS TO MOVE
NORTH FROM THE CAROLINAS. WINDS ARE GENERALLY E-SE 5-10 KT ACROSS
THE REGION AND WILL GRADUALLY SHFT TO THE SW BY MON MORNING.
MODELS INDICATE A WEAK TROF/LOW PRES OVER EASTERN NC WILL MOVE NORTH
OF THE AREA OVERNIGHT. A COLD FRONT WILL THEN SWING THRU THE AREA
MON MORNING AHEAD OF A COLDER SURGE OF ARCTIC AIR THAT WILL MOVE
THRU DURING THE AFTN/EVENING. RAIN/DRIZZLE AND MVFR/IFR CIGS WILL
AFFECT THE REGION TONIGHT INTO EARLY MON MORNING. CONDS WILL
IMPROVE AFTER FROPA BUT WINDS WILL PICK UP SIGNIFICANTLY THRU THE
DAY GUSTING TO 20-25 KT BY THE AFTN.
VERY COLD AND DRY FOR TUE WITH GUSTY NW WINDS.
&&
.MARINE...
THERE ARE TWO WEATHER FEATURES TO KEEP AN EYE ON THIS EVENING. THE
FIRST SYSTEM IS A DEVELOPING COASTAL LOW THAT IS CURRENTLY LOCATED
ALONG THE SC COAST. THIS SYSTEM WILL MOVE NWD ALONG THE CAROLINA
COAST AND THROUGH THE MID ATLANTIC REGION TONIGHT...SPREADING
RAINFALL OVER THE WATERS. SE WINDS WILL INCREASE THROUGH THE
EVENING AS THE COASTAL LOW DEEPENS AS IT APPROACHES THE WATERS.
EXPECT WIND SPEEDS OF GENERALLY 15-25 KT FOR COASTAL WATERS AND
10-15 KT BAY/RIVERS/SOUND. SEAS FROM THE VA/NC BORDER TO CURRITUCK
LIGHT HAVE FALLEN TO 4 FT BUT SHOULD RISE BACK UP TO 5 FT RATHER
QUICKLY THIS EVENING AS SE WINDS INCREASE. THE SE WIND DIRECTION
MAY ALSO CAUSE 4 FT WAVES TO FILTER INTO THE CTRL MOUTH OF CHES
BAY THIS EVENING...OTHERWISE WAVES SHOULD AVERAGE 2-3 FT TONIGHT.
THE NEXT FEATURE TO WATCH CAREFULLY IS A VERY STRONG ARCTIC COLD
FRONT THAT IS STILL EXPECTED TO CROSS THE WATERS MON MORNING
THROUGH AFTN. THE COLD FRONT WILL RAPIDLY STRENGTHEN TONIGHT INTO
MON MORNING AS IT MOVES FROM THE OH/TN VALLEYS INTO THE ERN GREAT
LAKES. S WINDS OF ROUGHLY 20-30 KT MON MORNING WILL QUICKLY VEER
TO THE NW BEHIND THE VIGOROUS FRONTAL PASSAGE. EXTREMELY TIGHT
TEMPERATURE AND PRESSURE GRADIENTS BEHIND THE FRONT WILL CAUSE
WINDS TO RAPIDLY INCREASE TO 25-35 KT WITH GUSTS UP TO 40 KT OVER
CHES BAY AND THE COASTAL WATERS...LIKELY BEGINNING BY LATE MON
MORNING. WAVES/SEAS WILL RESPOND QUICKLY TO THE RAPID INCREASE IN
WIND SPEEDS...WITH WAVES BUILDING TO 4-6 FT ON CHES BAY AND SEAS
BUILDING TO 5-8 FT ALL COASTAL WATERS. GALE FORCE GUSTS (AND WINDS
OVERALL) ARE ANTICIPATED TO INTENSIFY MON NIGHT AS THE VERY COLD
ARCTIC AIRMASS BLASTS OVER THE WATERS. MODEL GUIDANCE IS
DRASTICALLY UNDERCUTTING THE WIND POTENTIAL OVER THE WATERS AND
HAVE GONE AT LEAST 10 KT ABOVE THE STRONGEST MODEL(S). EVEN BY
DOING THIS...CURRITUCK SOUND AND THE ERN VA RIVERS STAY WITHIN
STRONG SCA CONDITIONS. IN REGARD TO THE GALES...THERE IS A LEVEL
OF UNCERTAINTY AS TO WHEN THEY SHOULD SUBSIDE AND ARE THEN
FOLLOWED BY STRONG SCA CONDITIONS. MAIN CONCERN IS THAT THE STRONG
CAA OVER LAND AND WATER SURFACES EARLY MON NIGHT WILL START TO
EQUALIZE FASTER THAN ANTICIPATED LATE MON NIGHT/EARLY TUE MORNING.
HOWEVER...THE MUCH COLDER AIR TEMPS OVER THE WARMER WATERS SHOULD
BE ENOUGH TO ERASE THIS UNCERTAINTY. HAVE DECIDED TO ISSUE A GALE
WARNING TONIGHT THROUGH EARLY TUE MORNING FOR CHES BAY AND COASTAL
WATERS FROM FENWICK ISLAND TO CURRITUCK LIGHT FOR THE ADVERSE
CONDITIONS EXPECTED. IF THE AIR/WATER TEMPERATURE DIFFERENCES
RESULT IN STRONGER WINDS MON NIGHT...THEN GALE HEADLINES MAY NEED
TO BE EXTENDED THROUGH EARLY TUE AFTN (WILL MONITOR CLOSELY).
W WINDS REMAIN STRONG THROUGH TUE. AS HIGH PRESSURE BUILDS INTO
THE REGION FROM THE WEST LATE IN THE DAY...THE TEMP/PRESSURE
GRADIENTS BEGIN TO RELAX...THUS ALLOWING WINDS TO SLOWLY DIMINISH
THROUGH TUE EVENING. SEAS SHOULD FOLLOW THE SAME TREND DURING THIS
TIME BUT SHOULD NOT FALL BELOW 5 FT UNTIL CLOSER TO WED MORNING.
HIGH PRESSURE CROSSES THE WATERS WED/THU WITH MORE BENIGN
CONDITIONS EXPECTED. THE NEXT LOW PRESSURE SYSTEM TO IMPACT THE
MID ATLANTIC REGION IS EXPECTED TO CROSS THE WATERS THU NIGHT INTO
EARLY FRI.
&&
.TIDES/COASTAL FLOODING...
TIDES WILL RUN ABOUT 0.5 FEET ABOVE NORMAL DURING THE NEXT TWO HIGH
TIDE CYCLES (OR THROUGH MONDAY MORNING`S HIGH TIDE)...HOWEVER
WATER LEVELS ARE EXPECTED TO REMAIN WELL BELOW ANY MINOR FLOODING
THRESHOLDS. TIDES ARE ON TREND TO FALL 0.5 TO 1.0 FEET BELOW
NORMAL BEHIND THE STRONG ARCTIC FRONTAL PASSAGE MONDAY MORNING.
BLOWOUT TIDES MAY BE POSSIBLE ALONG WESTERN PORTIONS OF
CHESAPEAKE BAY AND THE ATLANTIC OCEAN NEAR OCEAN CITY BY THE
SECOND LOW TIDE CYCLE ON TUESDAY.
&&
.CLIMATE...
VERY COLD WEATHER IS EXPECTED FROM MON NGT INTO WED...
RECORD LOW TEMP TUE JAN 7:
RIC 12/1988
ORF 13/1884
SBY 7/1919
ECG 15/1959
WAL 12/1988
RECORD LOW HIGH TEMP TUE JAN 7:
RIC 21/1996
ORF 28/1878
SBY 24/1988
ECG 32/1988
WAL 28/1973
RECORD LOW TEMP WED JAN 8:
RIC -8/1942
ORF 13/1970
SBY -4/1912
ECG 16/1968
WAL 14/1970
THE LAST TIME THE HIGH TEMP DIDN`T REACH 20 DEGREES F:
RIC 18 DEG F 2/4/1996 (SNOW DEPTH 2 INCHES)
ORF 13 DEG F 1/19/1994 (SNOW DEPTH TRACE)
SBY 18 DEG F 1/10/2004 (SNOW DEPTH 0)
ECG 16 DEG F 1/21/1985
WAL 19 DEG F 2/4/1996 (SNOW DEPTH 7 INCHES)
THE LAST TIME WIND CHILLS WERE BELOW ZERO:
RIC 12/20/2004
ORF 12/20/2004
SBY 1/22/2011
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST TUESDAY FOR ANZ633-635>638.
GALE WARNING UNTIL 7 AM EST TUESDAY FOR ANZ630>632-634-650-652-
654-656-658.
&&
$$
SYNOPSIS...ALB
NEAR TERM...ALB/JAB
SHORT TERM...ALB
LONG TERM...BMD
AVIATION...MPR/JEF
MARINE...BMD
TIDES/COASTAL FLOODING...
CLIMATE...
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
643 PM EST SUN JAN 5 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 445 PM EST SUN JAN 5 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW THE CENTER OF AN ELONGATED
POLAR VORTEX OVER NRN ONTARIO. A SHORTWAVE WAS DIVING SE THRU THE
NRN PLAINS...CAUSING THE ELONGATION OF THE VORTEX INTO THE NRN
PLAINS. THE CORE OF THE VERY COLD ARCTIC AIR MASS RESIDES FROM NRN
ONTARIO INTO SCNTRL CANADA AND THE FAR NRN PLAINS. PER 12Z RAOBS...
850MB TEMPS ARE IN THE -29C TO -34C RANGE ACROSS SCNTRL CANADA INTO
THE FAR NCNTL CONUS. LATEST RUC ANALYSIS INDICATES 850MB TEMPS
RANGING FROM -25C OVER WRN LAKE SUPERIOR TO AROUND -19C OVER FAR SE
LAKE SUPERIOR. OF COURSE...THIS IS LEADING TO LES OFF LAKE SUPERIOR
IN WNW LOW-LEVEL FLOW. HOWEVER...VERY DRY AIR MASS/LOW INVERSION
(3-5KFT LOWEST W PER LATEST RUC) IS GREATLY LIMITING LES INTENSITY.
PLUS...IT DOESN`T HELP THAT VERY COLD AIR HAS ELIMINATED THE DGZ FOR
THE WRN LAKE SUPERIOR LES. ON THE OTHER HAND...THE RESULTING SMALL
SNOWFLAKES ARE LEADING TO SHARPLY REDUCED VIS WHERE LES IS OCCURRING
(VIS AT KCMX HAS BEEN DOWN TO 1/2SM AT TIMES THIS AFTN...AND WEBCAMS
HAVE SHOWN QUITE LOW VIS AT TIMES).
AS THE ELONGATED POLAR VORTEX SWINGS INTO THE UPPER GREAT LAKES
MON...THERE WILL BE A SIGNIFICANT LIFTING OF THE INVERSION AND
DEEPENING OF MOISTURE. THIS WILL GRADUALLY BEGIN TONIGHT...BUT WILL
LARGELY TAKE PLACE DURING THE DAY MON. AS A RESULT...THERE WILL BE A
NOTABLE INCREASE IN LAKE EFFECT SNOW COVERAGE...AND INTENSITY WILL
INCREASE AS WELL. HOWEVER...WITH THE COLD AIR MASS ELIMINATING THE
DGZ...SNOW-TO-WATER RATIOS WILL BE POOR...PROBABLY DOWN TOWARD 10 TO
1 AS HAS BEEN OBSERVED IN PAST ARCTIC AIR MASSES SIMILAR TO THE
MAGNITUDE OF THIS ONE. SNOW WILL BE POWDERY AND VERY EFFECTIVE AT
REDUCING VIS. WITH THE INCREASE IN LES COVERAGE...WHITEOUTS WILL
PROBABLY BECOME NEARLY CONSTANT IN THE SNOWBELTS FAVORED BY NW WINDS
LATE TONIGHT AND ESPECIALLY MON. TONIGHT...LOW-LEVEL WINDS WILL
VEER MORE TOWARD THE NNW IN RESPONSE TO THE DEEPENING LOW LIFTING
NNE THRU THE LWR LAKES. THE VEERING WILL BE MORE PRONOUNCED OVER THE
ERN LAKE WHERE LAND BREEZE ENHANCEMENT OFF ONTARIO WILL AID THE
VEERING. THIS WILL LEAD TO STRENGTHENING CONVERGENCE INTO
ALGER/LUCE/SCHOOLCRAFT COUNTIES. WITH THE DGZ STILL LINGERING IN THE
LOWER PART OF THE CONVECTIVE LAYER IN THAT AREA...SHOULD BE ABLE TO
GET ACCUMULATIONS INTO THE 2 TO 4 INCH RANGE. COMBINED WITH SOME
INCREASE IN WINDS TO GENERATE BLSN...ADVY LOOKS ON TRACK FOR THAT
AREA. EVEN THOUGH THE DGZ IS ELIMINATED MON...SIMILAR ACCUMULATIONS
SHOULD OCCUR GIVEN LINGERING ENHANCED CONVERGENCE AND DEEP MOISTURE
PROFILE. OUT W...SNOW ACCUMULATIONS WILL BE ON THE ORDER OF 1-2 TO
PERHAPS 3IN/12HR TONIGHT/MON.
AS FOR TEMPS/WIND CHILLS...WITH LOW-LEVEL WINDS VEERING TONIGHT...
THERE SHOULD BE AN INCREASE IN LAKE EFFECT CLOUD COVER ACROSS MUCH
OF THE AREA. HAVE THUS OPTED TO RAISE MINS A FEW DEGREES IN MANY
LOCATIONS. TEMPS MAY STILL BOTTOM OUT AROUND -25F OVER THE FAR W
ALONG THE MI/WI BORDER...BUT IF CLOUD COVER IS QUICKER TO DEVELOP
AND MORE PERSISTENT...TEMPS MAY NOT FALL THAT LOW. IN GENERAL...MOST
OF THE W HALF OF UPPER MI WILL SEE MINS IN THE -10F TO -20F RANGE
WITH WIND CHILLS FALLING TO -30 TO -45F. WITH THE CORE OF THE COLD
OVER THE AREA MON...EXPECT INTERIOR W LOCATIONS TO FAIL TO RISE
ABOVE -10F. ONLY AREAS TO GET JUST ABOVE 0F WILL BE OVER THE E.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 515 PM EST SUN JAN 5 2014
.MONDAY NIGHT INTO TUESDAY...W TO WNW LOW LEVEL WINDS WILL CONTINUE
BETWEEN LOW PRES LIFTING NNE INTO HUDSON BAY AND ARCTIC HIGH PRES
BUILDING FROM THE NRN PLAINS TO THE UPPER MS VALLEY. 850 MB TEMPS
WILL GRADUALLY MODERATE FROM THE -25C TO -30C RANGE TO -17C TO -22C
FROM 00Z/TUE TO 00Z/WED. HOWEVER...SFC TEMPS WILL CLIMB ONLY
SLIGHTLY. WINDS WILL ALSO DIMINISH TO AROUND 10 MPH BY TUE MORNING.
HOWEVER...WITH TEMPS AGAIN FALLING INTO THE -12 TO -25 RANGE...WIND
CHILL VALUES OF -30 TO -45 WILL REMAIN IN THE WARNING CATEGORY OVER
MOST OF THE CWA. LES WILL PERSIST FOR THE KEWEENAW AND THE NE CWA(E
OF MUNISING). THE HIGHER RES MODELS SUGGEST THAT LOW LEVEL CONV OVER
THE WRN LAKE MAY BOOST SNOWFALL RATES INTO THE KEWEENAW(NEAR OR JUST
SOUTH OF HOUGHTON) AND NEAR THE PICTURED ROCKS AND GRAND MARAIS.
HOWEVER...WITH THE VERY COLD AIR AND NO DGZ AVAILABLE...SLR VALUES
WILL REMAIN LOW AND LIMIT SNOW ACCUMULATIONS TO THE 1 TO 3 INCH PER
12 HOUR WEST AND POSSIBLY 2 TO 4 INCHES EAST.
TUE NIGHT AND WED...WRLY FLOW LES WILL CONTINUE AS THE AIRMASS
MODERATES. WITH THE DGZ MOVING BACK CLOSER TO THE CONVECTIVE
LAYER...SLR VALUES WILL INCREASE. HOWEVER...THE VERY AIR UPSTREAM
WILL REMAIN UNFAVORABLE FOR MORE SIGNIFICANT LES. SO...SNOWFALL RATES
WILL GENERALLY REMAIN LIGHT...IN THE 1 TO 3 INCH RANGE...WITH THE
GREATEST AMOUNTS REMAINING OVER THE KEWEENAW AND ALONG THE SHORELINE
NEAR GRAND MARAIS. WIND CHILLS WILL ALSO NOT BE AS SEVERE AS WINDS
DIMINISH CLOSER TO 5 MPH INLAND AS TEMPS DROP INTO THE -10 TO -20
RANGE GIVING WIND CHILL VALUES FROM -20 TO -30.
THU-SUN...THE MODELS SHOW A TRANSITION TO A MORE ZONAL PATTERN WITH
SEPARATED NRN AND SRN STREAMS. AFTER BACKING WINDS TO SW WILL END THE
LES OVER THE KEWEENAW THU...MAINLY DRY WEATHER IS EXPECTED INTO THE
WEEKEND WITH MUCH MILDER CONDITIONS. HIGH TEMPS SHOULD CLIMB BACK
INTO THE UPPER 20S FRI AND TO AROUND 30 FOR THE WEEKEND. ALTHOUGH THE
00Z/05 ECMWF RUN SHOWED A MORE PHASED TROUGH BY SUN THAT BRINGS UP
ENOUGH WARM AIR AND MOISTURE FOR RAIN...THE 12Z/05 RUN FLIPPED BACK
TO A MORE SEPARATE NRN STREAM WITH THE SRN SHRTWV SLIDING INTO THE
LOWER MS VALLEY SIMILAR TO THE GFS/GEFS. HOWEVER...CONFIDENCE IN ANY
WEATHER DETAILS BEYOND THE MILDER AIR FOR THE WEEKEND REMAINS LOW.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 643 PM EST SUN JAN 5 2014
EXTREME COLD AIRMASS MOVING ACROSS THE UPPER GREAT LAKES WILL ALLOW
FOR LAKE EFFECT SNOW SHOWERS TO CONTINUE THROUGH THE PERIOD. KCMX
WILL LIKELY BE IMPACTED BY SNOW SHOWERS FOR THE ENTIRE PERIOD...AND
THEY WILL LIKELY INTENSIFY WHEN THE POLAR VORTEX MOVES OVERHEAD
LATER TONIGHT...COMBINED WITH BETTER LOW LEVEL CONVERGENCE. THIS
SHOULD ALLOW PREDOMINATE LIFR CONDITIONS TO PERSIST LATER TONIGHT
AND FOR MOST OF THE DAY ON MONDAY MAINLY DUE TO THE FINE SNOWFLAKES
ASSOCIATED WITH THE ARCTIC AIRMASS REDUCING VSBYS. AS FOR
KIWD...THEY ARE CURRENTLY VFR WITH LOW LEVEL WINDS TURNING PUSHING
THE LAKE CLOUDS/SNOW NE OF THE SITE. AS THE LOW OVER THE SRN LAKES
MOVES NORTHWARD...EXPECT THE GRADIENT FLOW TO HELP TURN WINDS BACK
TO THE W-NW OVERNIGHT WHICH SHOULD ALLOW FOR MVFR OR IFR CONDITIONS
TO RETURN. FINALLY...AT KSAW...VFR CONDITIONS SHOULD PERSIST THIS
EVENING BEFORE MVFR CONDITIONS RETURN OVERNIGHT INTO MONDAY AS THE
FLOW VEERS AROUND TO THE NW WHICH MAY ALLOW FOR SOME LIGHT SNOW AND
MVFR CLOUDS TO MOVE IN OFF THE LAKE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 515 PM EST SUN JAN 5 2014
PRES GRADIENT WILL SLOWLY INCREASE TONIGHT THRU MON...RESULTING IN
AN INCREASE IN WINDS. LOOKS LIKE 35KT GALES WILL DEVELOP OVER
PORTIONS OF ERN LAKE SUPERIOR LATE TONIGHT OR MON MORNING...AIDED BY
LAND BREEZE CONVERGENCE. AS PRES GRADIENT TIGHTENS A LITTLE MORE...
WILL NEED TO WATCH FOR AN EXPANSION OF GALES TO MORE OF CNTRL/ERN
LAKE SUPERIOR MON NIGHT/TUE. WITH VERY COLD AIR MASS OVER THE AREA
FOR THE NEXT COUPLE OF DAYS...WINDS/WAVES WILL LEAD TO HEAVY
FREEZING SPRAY OVER MUCH OF LAKE SUPERIOR. WINDS WILL DIMINISH
DURING THE MIDWEEK PERIOD AS THE COLD EASES AND HIGH PRES MOVES
ACROSS THE GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL WARNING UNTIL 11 AM EST /10 AM CST/ TUESDAY FOR
MIZ001>005-009>013-084.
WIND CHILL ADVISORY UNTIL 7 PM EST /6 PM CST/ THIS EVENING FOR
MIZ002-009-010-084.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST MONDAY FOR MIZ006-007-
014-085.
WIND CHILL WARNING FROM 7 PM MONDAY TO 11 AM EST TUESDAY FOR
MIZ006-007-014-085.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ WEDNESDAY
FOR LSZ162-243>245-248>251-263>267.
GALE WARNING FROM 7 AM MONDAY TO 1 AM EST WEDNESDAY FOR LSZ265-
266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLB
AVIATION...MRD
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
436 PM EST SAT JAN 4 2014
.UPDATE...
ISSUED AT 709 AM EST SAT JAN 4 2014
EXTENDED GOING WINTER STORM WARNING FOR ALGER COUNTY THRU 15Z WITH
SGNFT RADAR ECHOES LINGERING OVER THAT AREA UNDER THE DPVA/H85-5
QVECTOR CNVGC AHEAD OF SHRTWV MOVING E INTO THE UPR LKS. LARGER
SCALE SUBSIDENCE/MID LVL DRYING IN THE WAKE OF THIS DISTURBANCE WL
CAUSE THE SN TO DIMINISH IN ALGER COUNTY BY LATE MRNG.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 505 AM EST SAT JAN 4 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW VIGOROUS SHRTWV
SHIFTING E FM MN INTO THE UPR GRT LKS. THIS DISTURBANCE IS REFLECTED
BY A SFC LO PRES TROF IN MN...WHILE ANOTHER WEAKER DISTURBANCE/LO
PRES IS SHIFTING THRU ONTARIO. ALTHOUGH THERE IS NO WELL DEFINED SFC
LO PRES CENTER...THE SHARP PRES GRADIENT BTWN THE GENERAL LO PRES
TROF TO THE W AND RETREATING SFC HI PRES OVER THE MID ATLANTIC
STATES IS SUPPORTING A VERY STRONG SW FLOW INTO THE UPR LKS...WITH
THE 00Z GRB RAOB SHOWING AN IMPRESSIVE SW WIND UP TO 70 KTS AT H85.
THE ISENTROPIC ASCENT ASSOCIATED WITH THIS STRONG SW FLOW SUPPORTED
A BAND OF HEAVIER SN THAT IMPACTED MAINLY THE NRN PORTION OF UPR MI
AS WELL AS AREAS DOWNWIND OF LK MI...WHERE THE FLOW OFF THE WATER
IN THE PRESENCE OF THE RETREATING ARCTIC AIRMASS ALLOWED FOR SGNFT
LK ENHANCEMENT/SN FALL RATES UP TO AN INCH PER HR. THE LLVL
DESTABILIZATION ALSO SHARPENED LLVL LAPSE RATES AND ALLOWED FOR SFC
WIND GUSTS NEAR THE BAY OF GREEN BAY/LK MI TO REACH AS HI AS 68 MPH
AT A SITE NEAR THOMPSON IN SCHOOLCRAFT COUNTY. THE AREA OF STRONGEST
LLVL WINDS/SHARPER ISENTROPIC ASCENT/SUPPORTING CENTER OF VIGOROUS
H85-5 QVECTOR CNVGC IS TENDING TO DRIFT E EARLY THIS MRNG...SO THE
SW WINDS/SN INTENSITY ARE DIMINSING A BIT. BUT ANOTHER AREA OF SN TO
THE W ASSOCIATED WITH THE DPVA/ACCOMPANYING DEEP LYR QVECTOR CNVGC
ACCOMPANYING THE MN SHRTWV IS TENDING TO PUSH BACK INTO THE AREA.
LOOKING FARTHER TO THE W...COLDER AIR IS PLOWING BACK INTO THE NRN
PLAINS BEHIND A COLD FNT SWEEPING THRU MN. AN EVEN COLDER ARCTIC
AIRMASS ASSOCIATED WITH ANOTHER SHRTWV DIGGING SEWD THRU
ALBERTA/SASKATCHEWAN IS APRCHG THE NRN PLAINS.
MAIN FCST CONCERNS IN THE SHORT TERM ARE POPS ASSOCIATED WITH APRCHG
MN SHRTWV AND THEN TEMPS/LES AS THE MUCH COLDER AIR UPSTREAM IN THE
WAKE OF THIS DISTURBANCE SURGES INTO THE UPR LKS.
TODAY...AREA OF DPVA/DEEP LYR QVECTOR CNVGC SUPPORTING THE AREA OF
WDSPREAD SN MOVING INTO THE WRN CWA EARLY THIS MRNG IS PROGGED TO
MOVE OUT OF THE ERN CWA BTWN 15Z-18Z...SO TRENDED SYNOPTIC SCALE
POPS DOWN W-E IN LINE WITH GOING FCST WITH ARRIVAL OF DNVA/CAD/DEEP
LYR QVECTOR DVGC AND STRONG SUBSIDENCE/MID LVL DRYING IN THE WAKE OF
MN SHRTWV PASSAGE. BUT OVER THE W...LES WL DVLP IN THE COLD NW FLOW
BEHIND THE FROPA AS H85 TEMPS FALL TOWARD -18C BY 00Z SUN.
HOWEVER...FCST SUBSIDENCE IS PROGGED TO DROP THE INVRN BASE TO AS LO
AS 3-4K FT. NAM/GFS/LOCAL WRF ARW FCST SNGS ALSO INDICATE GENERAL
SUBSIDENCE IN THE MIXED LYR BLO THE INVRN...SO LES AMOUNTS SHOULD BE
RELATIVELY LGT. HI RES MODELS INDICATE THE MORE FOCUSED LLVL CNVGC
WL IMPACT NRN ONTONAGON/SRN HOUGHTON COUNTY. ALTHOUGH TEMPS WL RISE
INTO THE 20S THIS MRNG BEFORE SFC COLD FNT NOW IN MN CLEARS THE CWA
W-E AND NEWBERRY IN THE AFTN...TEMPS WL FALL W-E FOLLOWING THE FROPA
WITH THE ARRIVAL OF THE COLDER H85 TEMPS.
TNGT...COLDER AIR ASSOCIATED WITH DIGGING SHRTWV IN WRN CANADA/
DEEPENING ARCTIC BRANCH IN THE PLAINS IS PROGGED TO STEADILY ADVECT
INTO THE UPR GRT LKS IN STEADY WNW FLOW/H925 WINDS 20-25KTS.
CONSENSUS OF FAVORED MODELS INDICATES H85 TEMPS WL FALL TO ARND -25C
OVER THE WRN CWA AND -18C OVER THE E BY 12Z SUN. ALTHOUGH THIS CHILL
WITH H85/LK WATER TEMP DIFFERENCE OVER 20C WL SUPPORT LES... HIER
RES MODELS ARE INDICATING LO INVRN BASE MAINTAINED BY ONGOING
SUBIDENCE THAT EXTENDS INTO THE MIXED LYR WL HAMPER LES AMOUNTS. SO
A RELATIVELY HI POP/LO QPF SCENARIO SEEMS TO BE IN STORE. THE
ARRIVING CHILL WL ALSO PUSH THE DGZ BLO THE SFC OVER THE WRN CWA...
SO THIS POOR SN GROWTH WL ALSO HAMPER LES AMOUNTS. BUT THE SMALL SN
FLAKE SIZE WL BE EFFICIENT AT REDUCING VSBY...ESPECIALLY AT EXPOSED
LOCATIONS NEAR LK SUP. EXPECT TEMPS OVER THE INTERIOR W HALF...WHERE
THE INCOMING AIRMASS WL BE MODIFIED LEAST BY THE WARMING OF LK
SUP...TO FALL AS LO AS 15 TO 20 BLO ZERO. WITH APRNT TEMPS LIKELY TO
FALL TO -25 TO -35...OPTED TO ISSUE A WIND CHILL ADVY FOR LATE TNGT
THRU SUN MRNG FOR THE INTERIOR W HALF COUNTIES EVEN THOUGH WIND
SPEEDS MAY NOT HOLD AOA THE THRESHOLD OF 10 MPH.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 435 PM EST SAT JAN 4 2014
NAM SHOWS A DEEP 500 MB TROUGH OVER THE CENTRAL U.S. 00Z MON WITH A
STRONG SOUTHERN STREAM SHORTWAVE NEAR CHICAGO 00Z MON. THE 500 MB
TROUGH MOVES EAST SUN NIGHT WITH THE TROUGH AXIS PUSHING ACROSS THE
CWA ON MON BEFORE THE TROUGH AND UPPER LEVEL LOWS PULL NORTHEAST ON
WED. WHAT THIS WILL MEAN IS VERY COLD AIR MOVING ACROSS THE AREA.
12Z NAM SEEMS TO BE FURTHER NORTHWEST WITH THE TRACK OF THE SFC LOW
FROM WHAT THE ECMWF HAS FOR SUNDAY NIGHT INTO MON. GFS AND ECMWF
SHOW SOME 850-500 MB Q-VECTOR CONVERGENCE SUN NIGHT AND ARE ALSO
FURTHER EAST WITH THE SFC LOW TRACK THAN THE NAM IS. SFC LOW 00Z MON
WITH ECMWF AND GFS IS OVER CENTRAL OHIO WHILE NAM IS OVER WESTERN
OHIO AND AT 06Z MON SFC LOW OFF THE ECMWF AND GFS IS NEAR BUFFALO
NEW YORK WHILE NAM HAS IT NEAR KITCHENER ONTARIO. WILL GO WITH THE
FARTHER EAST TRACK WHICH WILL NOT MEAN MUCH EXCEPT THAT THE SYSTEM
SNOW WILL STAY OUT OF THE AREA AND LAKE EFFECT SNOW SHOWERS WILL BE
THE RULE INSTEAD FOR THIS FORECAST PERIOD WITH ACCUMULATIONS IN THE
NORTHWEST WIND AFFECTED SNOW BELTS. MAIN STORY WILL BE THE COLD
TEMPERATURES AND THE WIND SPEEDS. WIND SPEEDS WILL STAY UP SUN NIGHT
THROUGH TUE NIGHT WITH COLD TEMPERATURES. WIND CHILL VALUES WILL
FALL TO AS LOW AS -50F AND WILL GO WITH WIND CHILL WARNINGS FOR MOST
OF THE AREA. IF WINDS ARE LESS THAN FORECASTED...COULD GET COLDER
AND IF WINDS STAY UP...LOW TEMPERATURES WOULD BE WARMER. EITHER
WAY...WIND CHILL VALUES LOOK TO BE IN THE WARNING CRITERIA AND WILL
GO WITH WIND CHILL WARNINGS. DID NOT MAKE TOO MANY CHANGES TO THE
GOING FORECAST FOR TEMPERATURES EXCEPT FOR A FEW MINOR TWEAKS HERE
AND THERE AND DID NOT MAKE TOO MANY CHANGES TO THE POPS EITHER.
IN THE EXTENDED...GFS AND ECMWF SHOW A BROAD 500 MB TROUGH 12Z WED
OVER THE U.S. WITH COLD AIR CONTINUING TO MOVE ACROSS THE AREA...BUT
SOME MODIFICATION HAS ALREADY TAKEN PLACE AS THE POLAR VORTEX AND
EXTREME COLD AIR WILL HAVE MOVED OFF TO THE NORTHEAST BY THAT TIME.
NOT MUCH CHANGES FOR 12Z THU FOR THE UPPER PATTERN. A DEEPENING
TROUGH MOVES INTO THE ROCKIES 12Z FRI WHICH MOVES INTO THE UPPER
GREAT LAKES 12Z SAT WITH WARMER AIR MOVING INTO THE AREA FRI INTO
SAT. TEMPERATURES WILL ACTUALLY GO ABOVE NORMAL FOR FRI INTO
SATURDAY. WILL GO DRY FOR THU NIGHT AND FRIDAY AS WINDS ARE
SOUTHWEST AT THAT TIME AND PUSH THE LAKE EFFECT TO THE NORTH OF THE
AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1246 PM EST SAT JAN 4 2014
WITH INCREASINGLY COLDER AIR FLOWING INTO THE UPPER LAKES...LAKE
EFFECT SNOW SHOWERS WILL BE THE RULE OFF LAKE SUPERIOR IN W TO NW
FLOW. KIWD WILL BE NEAR THE SRN EDGE OF THE LAKE EFFECT SNOW
SHOWERS. IN GENERAL...MVFR CONDITIONS SHOULD PREVAIL THRU THE FCST
PERIOD. HOWEVER...EXPECT SOME PERIODS OF IFR FOR THE NEXT FEW HRS
BEFORE SUBSIDENCE/DRYING IN THE WAKE OF THE COLD FRONT THAT PASSED
EARLIER TODAY BECOME MORE DOMINANT. AT KCMX...PERSISTENT LAKE EFFECT
SNOW SHOWERS SHOULD LEAD TO PREVAILING IFR CONDITIONS. HOWEVER...
THERE WILL BE PERIODS OF LIFR FOR MUCH OF THE AFTN. AS AIR MASS
BECOMES EXTREMELY COLD...SNOWFLAKES WILL BECOME SMALL...LEADING TO A
TREND FOR INCREASINGLY LOWER VIS WITH TIME SUN/MON. AS A
RESULT...THERE MAY BE AN EXTENDED PERIOD OF LIFR VIS DEVELOPING AT
SOME POINT SUN AT KCMX. AT KSAW...OCNL -SHSN JUST BEHIND PASSING
COLD FRONT WILL LEAD TO MVFR/OCNL IFR FOR THE NEXT COUPLE OF HRS.
THEN...THERE SHOULD BE ENOUGH DRYING/SUBSIDENCE TO CAUSE CONDITIONS
TO IMPROVE TO VFR LATER TODAY/TONIGHT IN THE PRESENCE OF A DOWNSLOPE
WNW FLOW. MVFR CONDITIONS MAY RETURN SUN MORNING AS WINDS VEER A
LITTLE MORE NORTHERLY.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 435 PM EST SAT JAN 4 2014
EVEN THOUGH THE NW WINDS WILL BE UP TO ONLY 25-30 KTS TONIGHT...THE
ARRIVAL OF BITTERLY COLD ARCTIC AIR/SUFFICIENTLY HI WAVES WILL
RESULT IN WIDESPREAD HEAVY FREEZING SPRAY THROUGH TUESDAY NIGHT.
NEXT GALE EVENT WOULD BE NORTHWEST GALES TO 35 KNOTS OVER PORTIONS
OF CENTRAL AND EASTERN LAKE SUPERIOR MONDAY AFTERNOON THROUGH
TUESDAY EVENING. HIGH PRESSURE WILL RETURN WEDNESDAY INTO THURSDAY
AND BRING WINDS DOWN BELOW 20 KNOTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL WARNING FROM 7 PM EST /6 PM CST/ SUNDAY TO 11 AM EST
/10 AM CST/ TUESDAY FOR MIZ001>005-009>013-084.
WIND CHILL ADVISORY FROM MIDNIGHT EST /11 PM CST/ TONIGHT TO 7
PM EST /6 PM CST/ SUNDAY FOR MIZ002-009-010-084.
WIND CHILL WARNING FROM 7 PM MONDAY TO 11 AM EST TUESDAY FOR
MIZ006-007-014-085.
WIND CHILL ADVISORY FROM 7 PM SUNDAY TO 1 PM EST MONDAY FOR
MIZ006-007-014-085.
WIND CHILL ADVISORY FROM MIDNIGHT EST /11 PM CST/ TONIGHT TO
NOON EST /11 AM CST/ SUNDAY FOR MIZ004-005-011.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM 7 PM SUNDAY TO 7 AM EST
WEDNESDAY FOR LSZ267.
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ266-267.
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ WEDNESDAY
FOR LSZ162-263>266.
HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST MONDAY FOR
LSZ243>245-248>251.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...KC
SHORT TERM...KC
LONG TERM...07
AVIATION...ROLFSON
MARINE...07
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
426 PM EST SAT JAN 4 2014
.UPDATE...
ISSUED AT 709 AM EST SAT JAN 4 2014
EXTENDED GOING WINTER STORM WARNING FOR ALGER COUNTY THRU 15Z WITH
SGNFT RADAR ECHOES LINGERING OVER THAT AREA UNDER THE DPVA/H85-5
QVECTOR CNVGC AHEAD OF SHRTWV MOVING E INTO THE UPR LKS. LARGER
SCALE SUBSIDENCE/MID LVL DRYING IN THE WAKE OF THIS DISTURBANCE WL
CAUSE THE SN TO DIMINISH IN ALGER COUNTY BY LATE MRNG.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 505 AM EST SAT JAN 4 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW VIGOROUS SHRTWV
SHIFTING E FM MN INTO THE UPR GRT LKS. THIS DISTURBANCE IS REFLECTED
BY A SFC LO PRES TROF IN MN...WHILE ANOTHER WEAKER DISTURBANCE/LO
PRES IS SHIFTING THRU ONTARIO. ALTHOUGH THERE IS NO WELL DEFINED SFC
LO PRES CENTER...THE SHARP PRES GRADIENT BTWN THE GENERAL LO PRES
TROF TO THE W AND RETREATING SFC HI PRES OVER THE MID ATLANTIC
STATES IS SUPPORTING A VERY STRONG SW FLOW INTO THE UPR LKS...WITH
THE 00Z GRB RAOB SHOWING AN IMPRESSIVE SW WIND UP TO 70 KTS AT H85.
THE ISENTROPIC ASCENT ASSOCIATED WITH THIS STRONG SW FLOW SUPPORTED
A BAND OF HEAVIER SN THAT IMPACTED MAINLY THE NRN PORTION OF UPR MI
AS WELL AS AREAS DOWNWIND OF LK MI...WHERE THE FLOW OFF THE WATER
IN THE PRESENCE OF THE RETREATING ARCTIC AIRMASS ALLOWED FOR SGNFT
LK ENHANCEMENT/SN FALL RATES UP TO AN INCH PER HR. THE LLVL
DESTABILIZATION ALSO SHARPENED LLVL LAPSE RATES AND ALLOWED FOR SFC
WIND GUSTS NEAR THE BAY OF GREEN BAY/LK MI TO REACH AS HI AS 68 MPH
AT A SITE NEAR THOMPSON IN SCHOOLCRAFT COUNTY. THE AREA OF STRONGEST
LLVL WINDS/SHARPER ISENTROPIC ASCENT/SUPPORTING CENTER OF VIGOROUS
H85-5 QVECTOR CNVGC IS TENDING TO DRIFT E EARLY THIS MRNG...SO THE
SW WINDS/SN INTENSITY ARE DIMINSING A BIT. BUT ANOTHER AREA OF SN TO
THE W ASSOCIATED WITH THE DPVA/ACCOMPANYING DEEP LYR QVECTOR CNVGC
ACCOMPANYING THE MN SHRTWV IS TENDING TO PUSH BACK INTO THE AREA.
LOOKING FARTHER TO THE W...COLDER AIR IS PLOWING BACK INTO THE NRN
PLAINS BEHIND A COLD FNT SWEEPING THRU MN. AN EVEN COLDER ARCTIC
AIRMASS ASSOCIATED WITH ANOTHER SHRTWV DIGGING SEWD THRU
ALBERTA/SASKATCHEWAN IS APRCHG THE NRN PLAINS.
MAIN FCST CONCERNS IN THE SHORT TERM ARE POPS ASSOCIATED WITH APRCHG
MN SHRTWV AND THEN TEMPS/LES AS THE MUCH COLDER AIR UPSTREAM IN THE
WAKE OF THIS DISTURBANCE SURGES INTO THE UPR LKS.
TODAY...AREA OF DPVA/DEEP LYR QVECTOR CNVGC SUPPORTING THE AREA OF
WDSPREAD SN MOVING INTO THE WRN CWA EARLY THIS MRNG IS PROGGED TO
MOVE OUT OF THE ERN CWA BTWN 15Z-18Z...SO TRENDED SYNOPTIC SCALE
POPS DOWN W-E IN LINE WITH GOING FCST WITH ARRIVAL OF DNVA/CAD/DEEP
LYR QVECTOR DVGC AND STRONG SUBSIDENCE/MID LVL DRYING IN THE WAKE OF
MN SHRTWV PASSAGE. BUT OVER THE W...LES WL DVLP IN THE COLD NW FLOW
BEHIND THE FROPA AS H85 TEMPS FALL TOWARD -18C BY 00Z SUN.
HOWEVER...FCST SUBSIDENCE IS PROGGED TO DROP THE INVRN BASE TO AS LO
AS 3-4K FT. NAM/GFS/LOCAL WRF ARW FCST SNGS ALSO INDICATE GENERAL
SUBSIDENCE IN THE MIXED LYR BLO THE INVRN...SO LES AMOUNTS SHOULD BE
RELATIVELY LGT. HI RES MODELS INDICATE THE MORE FOCUSED LLVL CNVGC
WL IMPACT NRN ONTONAGON/SRN HOUGHTON COUNTY. ALTHOUGH TEMPS WL RISE
INTO THE 20S THIS MRNG BEFORE SFC COLD FNT NOW IN MN CLEARS THE CWA
W-E AND NEWBERRY IN THE AFTN...TEMPS WL FALL W-E FOLLOWING THE FROPA
WITH THE ARRIVAL OF THE COLDER H85 TEMPS.
TNGT...COLDER AIR ASSOCIATED WITH DIGGING SHRTWV IN WRN CANADA/
DEEPENING ARCTIC BRANCH IN THE PLAINS IS PROGGED TO STEADILY ADVECT
INTO THE UPR GRT LKS IN STEADY WNW FLOW/H925 WINDS 20-25KTS.
CONSENSUS OF FAVORED MODELS INDICATES H85 TEMPS WL FALL TO ARND -25C
OVER THE WRN CWA AND -18C OVER THE E BY 12Z SUN. ALTHOUGH THIS CHILL
WITH H85/LK WATER TEMP DIFFERENCE OVER 20C WL SUPPORT LES... HIER
RES MODELS ARE INDICATING LO INVRN BASE MAINTAINED BY ONGOING
SUBIDENCE THAT EXTENDS INTO THE MIXED LYR WL HAMPER LES AMOUNTS. SO
A RELATIVELY HI POP/LO QPF SCENARIO SEEMS TO BE IN STORE. THE
ARRIVING CHILL WL ALSO PUSH THE DGZ BLO THE SFC OVER THE WRN CWA...
SO THIS POOR SN GROWTH WL ALSO HAMPER LES AMOUNTS. BUT THE SMALL SN
FLAKE SIZE WL BE EFFICIENT AT REDUCING VSBY...ESPECIALLY AT EXPOSED
LOCATIONS NEAR LK SUP. EXPECT TEMPS OVER THE INTERIOR W HALF...WHERE
THE INCOMING AIRMASS WL BE MODIFIED LEAST BY THE WARMING OF LK
SUP...TO FALL AS LO AS 15 TO 20 BLO ZERO. WITH APRNT TEMPS LIKELY TO
FALL TO -25 TO -35...OPTED TO ISSUE A WIND CHILL ADVY FOR LATE TNGT
THRU SUN MRNG FOR THE INTERIOR W HALF COUNTIES EVEN THOUGH WIND
SPEEDS MAY NOT HOLD AOA THE THRESHOLD OF 10 MPH.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 426 PM EST SAT JAN 4 2014
NAM SHOWS A DEEP 500 MB TROUGH OVER THE CENTRAL U.S. 00Z MON WITH A
STRONG SOUTHERN STREAM SHORTWAVE NEAR CHICAGO 00Z MON. THE 500 MB
TROUGH MOVES EAST SUN NIGHT WITH THE TROUGH AXIS PUSHING ACROSS THE
CWA ON MON BEFORE THE TROUGH AND UPPER LEVEL LOWS PULL NORTHEAST ON
WED. WHAT THIS WILL MEAN IS VERY COLD AIR MOVING ACROSS THE AREA.
12Z NAM SEEMS TO BE FURTHER NORTHWEST WITH THE TRACK OF THE SFC LOW
FROM WHAT THE ECMWF HAS FOR SUNDAY NIGHT INTO MON. GFS AND ECMWF
SHOW SOME 850-500 MB Q-VECTOR CONVERGENCE SUN NIGHT AND ARE ALSO
FURTHER EAST WITH THE SFC LOW TRACK THAN THE NAM IS. SFC LOW 00Z MON
WITH ECMWF AND GFS IS OVER CENTRAL OHIO WHILE NAM IS OVER WESTERN
OHIO AND AT 06Z MON SFC LOW OFF THE ECMWF AND GFS IS NEAR BUFFALO
NEW YORK WHILE NAM HAS IT NEAR KITCHENER ONTARIO. WILL GO WITH THE
FARTHER EAST TRACK WHICH WILL NOT MEAN MUCH EXCEPT THAT THE SYSTEM
SNOW WILL STAY OUT OF THE AREA AND LAKE EFFECT SNOW SHOWERS WILL BE
THE RULE INSTEAD FOR THIS FORECAST PERIOD WITH ACCUMULATIONS IN THE
NORTHWEST WIND AFFECTED SNOW BELTS. MAIN STORY WILL BE THE COLD
TEMPERATURES AND THE WIND SPEEDS. WIND SPEEDS WILL STAY UP SUN NIGHT
THROUGH TUE NIGHT WITH COLD TEMPERATURES. WIND CHILL VALUES WILL
FALL TO AS LOW AS -50F AND WILL GO WITH WIND CHILL WARNINGS FOR MOST
OF THE AREA. IF WINDS ARE LESS THAN FORECASTED...COULD GET COLDER
AND IF WINDS STAY UP...LOW TEMPERATURES WOULD BE WARMER. EITHER
WAY...WIND CHILL VALUES LOOK TO BE IN THE WARNING CRITERIA AND WILL
GO WITH WIND CHILL WARNINGS. DID NOT MAKE TOO MANY CHANGES TO THE
GOING FORECAST FOR TEMPERATURES EXCEPT FOR A FEW MINOR TWEAKS HERE
AND THERE AND DID NOT MAKE TOO MANY CHANGES TO THE POPS EITHER.
IN THE EXTENDED...GFS AND ECMWF SHOW A BROAD 500 MB TROUGH 12Z WED
OVER THE U.S. WITH COLD AIR CONTINUING TO MOVE ACROSS THE AREA...BUT
SOME MODIFICATION HAS ALREADY TAKEN PLACE AS THE POLAR VORTEX AND
EXTREME COLD AIR WILL HAVE MOVED OFF TO THE NORTHEAST BY THAT TIME.
NOT MUCH CHANGES FOR 12Z THU FOR THE UPPER PATTERN. A DEEPENING
TROUGH MOVES INTO THE ROCKIES 12Z FRI WHICH MOVES INTO THE UPPER
GREAT LAKES 12Z SAT WITH WARMER AIR MOVING INTO THE AREA FRI INTO
SAT. TEMPERATURES WILL ACTUALLY GO ABOVE NORMAL FOR FRI INTO
SATURDAY. WILL GO DRY FOR THU NIGHT AND FRIDAY AS WINDS ARE
SOUTHWEST AT THAT TIME AND PUSH THE LAKE EFFECT TO THE NORTH OF THE
AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1246 PM EST SAT JAN 4 2014
WITH INCREASINGLY COLDER AIR FLOWING INTO THE UPPER LAKES...LAKE
EFFECT SNOW SHOWERS WILL BE THE RULE OFF LAKE SUPERIOR IN W TO NW
FLOW. KIWD WILL BE NEAR THE SRN EDGE OF THE LAKE EFFECT SNOW
SHOWERS. IN GENERAL...MVFR CONDITIONS SHOULD PREVAIL THRU THE FCST
PERIOD. HOWEVER...EXPECT SOME PERIODS OF IFR FOR THE NEXT FEW HRS
BEFORE SUBSIDENCE/DRYING IN THE WAKE OF THE COLD FRONT THAT PASSED
EARLIER TODAY BECOME MORE DOMINANT. AT KCMX...PERSISTENT LAKE EFFECT
SNOW SHOWERS SHOULD LEAD TO PREVAILING IFR CONDITIONS. HOWEVER...
THERE WILL BE PERIODS OF LIFR FOR MUCH OF THE AFTN. AS AIR MASS
BECOMES EXTREMELY COLD...SNOWFLAKES WILL BECOME SMALL...LEADING TO A
TREND FOR INCREASINGLY LOWER VIS WITH TIME SUN/MON. AS A
RESULT...THERE MAY BE AN EXTENDED PERIOD OF LIFR VIS DEVELOPING AT
SOME POINT SUN AT KCMX. AT KSAW...OCNL -SHSN JUST BEHIND PASSING
COLD FRONT WILL LEAD TO MVFR/OCNL IFR FOR THE NEXT COUPLE OF HRS.
THEN...THERE SHOULD BE ENOUGH DRYING/SUBSIDENCE TO CAUSE CONDITIONS
TO IMPROVE TO VFR LATER TODAY/TONIGHT IN THE PRESENCE OF A DOWNSLOPE
WNW FLOW. MVFR CONDITIONS MAY RETURN SUN MORNING AS WINDS VEER A
LITTLE MORE NORTHERLY.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 505 AM EST SAT JAN 4 2014
SW GALES AHEAD OF AN APPROACHING COLD FRONT OVER EASTERN LAKE
SUPERIOR WILL DIMINISH THIS MORNING WITH THE ARRIVAL OF A WEAKER
PRES GRADIENT. IT NOW APPEARS THE NW WINDS BEHIND THE FRONT WL NOT
BE AS STRONG AS EARLIER ANTICIPATED AND NOT REACH GALE THRESHOLDS
EXCEPT PERHAPS OVER THE E PART OF THE LAKE THIS AFTERNOON. SO OPTED
TO CANX THE GOING GALE WARNING FOR ALL BUT THAT AREA. DID SHORTERN
THE WARNING FOR THE E THIS EVENING SINCE THE MARGINAL GALES THERE
WILL DIMINISH BY THEN. EVEN THOUGH THE NW WINDS WILL BE UP TO ONLY
25-30 KTS INSTEAD OF 35 KTS THRU TONIGHT...THE ARRIVAL OF BITTERLY
COLD ARCTIC AIR/SUFFICIENTLY HI WAVES WILL RESULT IN WIDESPREAD
HEAVY FREEZING SPRAY...ESPECIALLY THIS AFTERNOON AND TONIGHT.
WEST TO NORTHWEST WINDS OF 15 TO 25 KNOTS WILL CONTINUE FROM SUNDAY
INTO MONDAY MORNING. THE TIGHTENING PRESSURE GRADIENT BETWEEN LOW
PRESSURE OVER THE NEW ENGLAND STATES AND INCOMING HIGH PRESSURE FROM
THE NORTHERN PLAINS WILL BRING NORTHWEST GALES TO 40 KNOTS TO MAINLY
CENTRAL AND EASTERN LAKE SUPERIOR MONDAY AFTERNOON INTO TUESDAY
EVENING. HIGH PRESSURE WILL RETURN WEDNESDAY INTO THURSDAY AND BRING
WINDS DOWN BELOW 20 KNOTS. APPROACHING LOW PRESSURE WILL BRING
SOUTHERLY WINDS 15 TO 25 KNOTS TO LAKE SUPERIOR FOR FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL WARNING FROM 7 PM EST /6 PM CST/ SUNDAY TO 11 AM EST
/10 AM CST/ TUESDAY FOR MIZ001>005-009>013-084.
WIND CHILL ADVISORY FROM MIDNIGHT EST /11 PM CST/ TONIGHT TO 7
PM EST /6 PM CST/ SUNDAY FOR MIZ002-009-010-084.
WIND CHILL WARNING FROM 7 PM MONDAY TO 11 AM EST TUESDAY FOR
MIZ006-007-014-085.
WIND CHILL ADVISORY FROM 7 PM SUNDAY TO 1 PM EST MONDAY FOR
MIZ006-007-014-085.
WIND CHILL ADVISORY FROM MIDNIGHT EST /11 PM CST/ TONIGHT TO
NOON EST /11 AM CST/ SUNDAY FOR MIZ004-005-011.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM 7 PM SUNDAY TO 7 AM EST
WEDNESDAY FOR LSZ267.
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ266-267.
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ WEDNESDAY
FOR LSZ162-263>266.
HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST MONDAY FOR
LSZ243>245-248>251.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...KC
SHORT TERM...KC
LONG TERM...07
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1227 PM EST SAT JAN 4 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 330 AM EST SAT JAN 4 2014
A COLD FRONT WILL DROP DOWN INTO THE AREA TODAY AND SLOWLY MOVE
THROUGH THE AREA THROUGH THE DAY ON SUNDAY. SOME LIGHT SNOW WILL
DEVELOP ALONG THIS FRONT...AND WILL BECOME MORE WIDESPREAD THIS
EVENING AS IT PRESSES SOUTHEAST. ADDITIONAL SNOW WILL DEVELOP AND
MOVE ALONG THIS FRONT WITH A WAVE OF LOW PRESSURE ON SUNDAY AND
SUNDAY EVENING.
MUCH COLDER AIR WILL THEN OVERSPREAD THE AREA LATE SUNDAY AND INTO
MONDAY. TEMPERATURES WILL MAINLY FALL SUNDAY NIGHT AND MONDAY.
STRONG WINDS WILL COMBINE WITH THE COLD TO PRODUCE WIND CHILLS WELL
BELOW ZERO. THE AREA HAS NOT SEEN THE AIR THIS COLD AT LEAST FOR A
FEW YEARS. TEMPERATURES WILL MODERATE LATE NEXT WEEK.
&&
.UPDATE...
ISSUED AT 1051 AM EST SAT JAN 4 2014
I AM SERIOUSLY CONSIDERING EXPANDING THE WINTER STORM WARNING AT
LEAST ONE ROW OF COUNTIES FARTHER NORTH WITH THE AFTERNOON
FORECAST UPDATE. SEEMS TO ME THE MODEL CONUS IS CONVERGING ON A
SOLUTION BETWEEN THE NAM AND THE GFS PUTTING THE HEAVIER
PRECIPITATION TONIGHT NEAR AND JUST SOUTH OF A LINE FROM NEAR
GRAND HAVEN TO GRAND RAPIDS TO ALMA. THE RAP 13Z AND NAM12 SHOW A
BAND OF .2 TO .4 QPF BY 12Z SUNDAY FROM ALONG THAT LINE...AS DOES
THE 12Z GFS. THIS SNOW BAND IS FGEN RELATED AND IS A REFLECTION
OF WHERE THE FRONT IS BETWEEN 850 AND 700 MB. WHICH TO ME
SUGGESTS HEAVY SNOW IS MORE THAN LIKELY ONE ROW OF COUNTIES
FATHER NORTH IN THE SHORT TERM. FOR NOW THOUGH I PLAN ON LEAVING
HEADLINES AS THEY ARE SINCE THE GFS IS STILL WELL SOUTH OF THE NAM
&&
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 330 AM EST SAT JAN 4 2014
WE WILL BE UPGRADING TO A WARNING FOR MOST OF THE AREA THAT WAS IN
THE WATCH. THE NW EDGE OF THE WATCH WILL BE TRANSITIONED TO AN
ADVISORY ALONG WITH SOME ADDITIONAL COUNTIES. THE MAIN PERIOD OF
CONCERN IN THE SHORT TERM IS FROM THIS EVENING INTO SUNDAY EVENING
WITH THE SNOW. THE WIND CHILL WATCH WILL BE MAINTAINED FOR THE TIME
BEING.
WE ARE EXPECTING SNOW TO BEGIN TO DEVELOP THIS MORNING ACROSS THE NW
CORNER OF THE CWFA. THE SNOW WILL START OUT RATHER LIGHT AS
THE AREA ALONG THE FRONT LIGHTS UP A BIT LIKELY AHEAD OF THE SHORT
WAVE THAT WILL APPROACH THE AREA FROM THE DAKOTAS. ALSO...THERE
LOOKS TO BE SOME LAKE ENHANCEMENT. DELTA T/S ARE NOT IN THE
TEENS...BUT THEY WILL BE ALMOST 10C WHICH IS USUALLY SUFFICIENT
ENOUGH FOR AT LEAST A SMALL BOOST FROM THE LAKE. THERE WILL ALSO BE
SOME ADDED CONVERGENCE FROM THE LAKE INFLUENCE THAT WILL ALSO HELP.
THE LIGHT SNOW WILL EXPAND A BIT THIS AFTERNOON AND THEN THIS
EVENING INTO THE CENTRAL PORTIONS OF THE AREA. THE AFOREMENTIONED
SHORT WAVE WILL INITIALLY ZIP TO THE NE OF THE CWFA AFTER 18Z TODAY.
WE WILL THEN SEE THE RRQ MOVE OVER THE AREA VIA A 140 KT JET STREAK
SOUTH OF JAMES BAY. THIS WILL ACT ON THE FRONT AND THE LIMITED LAKE
CONTRIBUTION TO SPREAD THE SNOW INLAND A BIT MORE. THE FRONT SHOULD
MOVE SE OF KGRR AFTER 00Z AND FOCUS THE BETTER SNOW DOWN THERE.
LIGHT SNOW WILL CONTINUE THEN ACROSS THE SE HALF OF THE CWFA LATER
TONIGHT AND EARLY SUN. WE LOSE THE UPPER JET DYNAMICS...BUT WE
CONTINUE WITH A GRADUAL ISENTROPIC ASCENT/OVERRUNNING SITUATION NW
OF THE FRONT THAT THEN STALLS OUT TO OUR SE. THIS FRONT WILL BE
AWAITING THE NEXT UPPER WAVE EXPECTED TO DIVE INTO THE SRN PLAINS
AROUND 12Z SUN BEFORE LIFTING NE TOWARD THE LOWER GREAT LAKES. THIS
WAVE WILL BRING ANOTHER ROUND OF SNOW ACROSS THE WARNING AREA SUN
AFTERNOON AND EVENING.
ONCE THE SYSTEM SNOW MOVES OUT SUN EVENING...WE WILL SEE NW FLOW
LAKE EFFECT BECOME ESTABLISHED WITH THE EXTREMELY COLD ARCTIC AIR
THAT WILL SPREAD ACROSS THE AREA.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 330 AM EST SAT JAN 4 2014
THE MAIN EMPHASIS IN THE LONG TERM CONTINUES TO BE ON THE BRUTALLY
COLD AIR MASS SWEEPING ACROSS MICHIGAN ON MONDAY AND TUESDAY. WIND
CHILLS ARE EXPECTED TO BE AROUND -25 OVER MOST OF THE AREA HOWEVER
VALUES ALONG THE I-94 CORRIDOR EAST OF KALAMAZOO MAY REACH AS LOW AS
-35 OR -40 MONDAY NIGHT WHERE A LK MI INFLUENCE PROBABLY WILL NOT BE
PRESENT AS SFC WINDS BECOME SOUTHWEST.
IN ADDITION TO THE SEVERE WIND CHILL READINGS... LAKE EFFECT SNOW
AND BLOWING SNOW WILL IMPACT THE AREA MONDAY AND TUESDAY.
ACCUMULATIONS WILL BE HELD DOWN DUE TO SMALL CRYSTAL SIZE BUT
VISIBILITIES SHOULD STILL BE GREATLY REDUCED AND ROADS WILL BE ICY
SINCE ROAD CHEMICALS WILL BE INEFFECTIVE WITH THE VERY COLD TEMPS.
THE REALLY COLD SFC AIR OF -10 TO -15 CURLING AROUND THE BOTTOM OF
LK MI INTO THE I-94 CORRIDOR REGION WILL LIKELY RESULT IN A NICE LOW
LEVEL CONVERGENCE/FGEN ZONE FOR THE LAKE EFFECT SNOW. A LENGTHY
EASTWARD/INLAND EXTENSION OF LAKE EFFECT SHOULD SET UP NEAR OR JUST
SOUTH OF THE I-96 CORRIDOR MONDAY NIGHT AND TUESDAY.
THE CORE OF THE COLDEST AIR LIFTS OUT TUESDAY NIGHT AND A MODERATING
TREND IN TEMPS IS EXPECTED FOR MID TO LATE WEEK. HIGHS BY FRIDAY
SHOULD BE UP NEAR 30. HOWEVER MORE LIGHT SNOW IS POSSIBLE WEDNESDAY
AND THURSDAY DUE TO WEAK WARM ADVECTION/ISENTROPIC LIFT PATTERN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1227 PM EST SAT JAN 4 2014
A COLD FRONT WAS CROSSING EASTERN WISCONSIN EARLY THIS AFTERNOON.
AN AREA OF MOSTLY LIGHT SNOW WAS DEVELOPING UPSTREAM...AROUND MKE
AND CHI. THIS WILL BE SPREADING INTO THE TAF SITES THROUGH THE
AFTERNOON. EXPECT CONDITIONS TO DETERIORATE TO A MIX OF MVFR AND IFR
ONCE THIS SNOW ARRIVES. CONDITIONS SHOULD TREND LOWER TO MOSTLY
IFR INTO THE EARLY EVENING AS MIXING DECREASES ALLOWING CEILINGS
TO LOWER FURTHER. ANOTHER SURGE OF STEADIER SNOWS ARE EXPECTED BY
MID SUNDAY MORNING RESULTING IN WIDESPREAD IFR AND LIFR.
SOUTHWEST WINDS WILL GRADUALLY DIMINISH THROUGH THE AFTERNOON AS
THE FRONT SAGS IN. GUSTS OF 20-25 KTS SHOULD BE EXITING THE AREA
BY ABOUT 20Z. THEN DROPPING OFF EVEN FURTHER BY MID EVENING TO 8
KTS OR LESS. THE LIGHTER WINDS WILL SHIFT TO THE NORTH OVERNIGHT.
&&
.MARINE...
ISSUED AT 1051 AM EST SAT JAN 4 2014
I HAVE DOWNGRADED THE GALE WARNING TO A SMALL CRAFT ADVISORY SINCE
WINDS ARE DIMINISHING AS I WRITE THIS. WE MAY NEED A GALE WARNING
AND FREEZING SPRAY WARNING SUNDAY NIGHT INTO MONDAY BUT WILL NOT
ISSUE THAT JUST YET.
&&
.HYDROLOGY...
ISSUED AT 315 PM EST FRI JAN 3 2014
A FLOOD ADVISORY IS IN EFFECT FOR THE FLAT RIVER AT SMYRNA. A
SUSPECTED ICE JAM UPSTREAM HAS CAUSED A SHARP RISE FOLLOWED BY A
SHARP DECLINE AT THE SMYRNA RIVER GAUGE. ICE JAMS CAN CAUSE RAPID
FLUCTUATIONS IN RIVER LEVELS.
RIVERS WILL CONTINUE GAINING ICE COVERAGE AND THICKNESS FOR THE
FORESEEABLE FUTURE. THOSE RIVERS THAT ICE OVER COMPLETELY WILL HAVE
A MINIMAL ICE JAM THREAT. RIVERS WITH JAGGED ICE BUILDUP ARE IN
DANGER OF EXPERIENCING JAMMING AND RAPID FLUCTUATIONS. 6 OR MORE
INCHES OF SNOW IS EXPECTED FOR SOUTHERN AND SOUTHEAST LOWER MICHIGAN
SATURDAY NIGHT THROUGH SUNDAY EVENING. A BLAST OF EXTREME COLD AIR
FOLLOWS THE SNOW ON SUNDAY NIGHT.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 1 AM EST
MONDAY FOR MIZ051-052-056>058-064.
WIND CHILL WATCH FROM LATE SUNDAY NIGHT THROUGH TUESDAY
AFTERNOON FOR MIZ037>040-043>046-050>052-056>059-064>067-
071>074.
WINTER STORM WARNING FROM 7 PM THIS EVENING TO 1 AM EST MONDAY
FOR MIZ059-065>067-071>074.
LM...SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
LMZ844>849.
&&
$$
UPDATE...WDM
SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...MEADE
AVIATION...JK
HYDROLOGY...EBW
MARINE...WDM
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1053 AM EST SAT JAN 4 2014
LATEST UPDATE...
UPDATE/MARINE
.SYNOPSIS...
ISSUED AT 330 AM EST SAT JAN 4 2014
A COLD FRONT WILL DROP DOWN INTO THE AREA TODAY AND SLOWLY MOVE
THROUGH THE AREA THROUGH THE DAY ON SUNDAY. SOME LIGHT SNOW WILL
DEVELOP ALONG THIS FRONT...AND WILL BECOME MORE WIDESPREAD THIS
EVENING AS IT PRESSES SOUTHEAST. ADDITIONAL SNOW WILL DEVELOP AND
MOVE ALONG THIS FRONT WITH A WAVE OF LOW PRESSURE ON SUNDAY AND
SUNDAY EVENING.
MUCH COLDER AIR WILL THEN OVERSPREAD THE AREA LATE SUNDAY AND INTO
MONDAY. TEMPERATURES WILL MAINLY FALL SUNDAY NIGHT AND MONDAY.
STRONG WINDS WILL COMBINE WITH THE COLD TO PRODUCE WIND CHILLS WELL
BELOW ZERO. THE AREA HAS NOT SEEN THE AIR THIS COLD AT LEAST FOR A
FEW YEARS. TEMPERATURES WILL MODERATE LATE NEXT WEEK.
&&
.UPDATE...
ISSUED AT 1051 AM EST SAT JAN 4 2014
I AM SERIOUSLY CONSIDERING EXPANDING THE WINTER STORM WARNING AT
LEAST ONE ROW OF COUNTIES FARTHER NORTH WITH THE AFTERNOON
FORECAST UPDATE. SEEMS TO ME THE MODEL CONSUS IS CONVERGING ON A
SOLUTION BETWEEN THE NAM AND THE GFS PUTTING THE HEAVIER
PRECIPITATION TONIGHT NEAR AND JUST SOUTH OF A LINE FROM NEAR
GRAND HAVEN TO GRAND RAPIDS TO ALMA. THE RAP 13Z AND NAM12 SHOW A
BAND OF .2 TO .4 QPF BY 12Z SUNDAY FROM ALONG THAT LINE...AS DOES
THE 12Z GFS. THIS SNOW BAND IS FGEN RELATED AND IS A REFLECTION
OF WHERE THE FRONT IS BETWEEN 850 AND 700 MB. WHICH TO ME
SUGGESTS HEAVY SNOW IS MORE THAN LIKELY ONE ROW OF COUNTIES
FATHER NORTH IN THE SHORT TERM. FOR NOW THOUGH I PLAN ON LEAVING
HEADLINES AS THEY ARE SINCE THE GFS IS STILL WELL SOUTH OF THE NAM
FOR SUNDAY AFTERNOON INTO SUNDAY NIGHT ON THE STORM QPF.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 330 AM EST SAT JAN 4 2014
WE WILL BE UPGRADING TO A WARNING FOR MOST OF THE AREA THAT WAS IN
THE WATCH. THE NW EDGE OF THE WATCH WILL BE TRANSITIONED TO AN
ADVISORY ALONG WITH SOME ADDITIONAL COUNTIES. THE MAIN PERIOD OF
CONCERN IN THE SHORT TERM IS FROM THIS EVENING INTO SUNDAY EVENING
WITH THE SNOW. THE WIND CHILL WATCH WILL BE MAINTAINED FOR THE TIME
BEING.
WE ARE EXPECTING SNOW TO BEGIN TO DEVELOP THIS MORNING ACROSS THE NW
CORNER OF THE CWFA. THE SNOW WILL START OUT RATHER LIGHT AS
THE AREA ALONG THE FRONT LIGHTS UP A BIT LIKELY AHEAD OF THE SHORT
WAVE THAT WILL APPROACH THE AREA FROM THE DAKOTAS. ALSO...THERE
LOOKS TO BE SOME LAKE ENHANCEMENT. DELTA T/S ARE NOT IN THE
TEENS...BUT THEY WILL BE ALMOST 10C WHICH IS USUALLY SUFFICIENT
ENOUGH FOR AT LEAST A SMALL BOOST FROM THE LAKE. THERE WILL ALSO BE
SOME ADDED CONVERGENCE FROM THE LAKE INFLUENCE THAT WILL ALSO HELP.
THE LIGHT SNOW WILL EXPAND A BIT THIS AFTERNOON AND THEN THIS
EVENING INTO THE CENTRAL PORTIONS OF THE AREA. THE AFOREMENTIONED
SHORT WAVE WILL INITIALLY ZIP TO THE NE OF THE CWFA AFTER 18Z TODAY.
WE WILL THEN SEE THE RRQ MOVE OVER THE AREA VIA A 140 KT JET STREAK
SOUTH OF JAMES BAY. THIS WILL ACT ON THE FRONT AND THE LIMITED LAKE
CONTRIBUTION TO SPREAD THE SNOW INLAND A BIT MORE. THE FRONT SHOULD
MOVE SE OF KGRR AFTER 00Z AND FOCUS THE BETTER SNOW DOWN THERE.
LIGHT SNOW WILL CONTINUE THEN ACROSS THE SE HALF OF THE CWFA LATER
TONIGHT AND EARLY SUN. WE LOSE THE UPPER JET DYNAMICS...BUT WE
CONTINUE WITH A GRADUAL ISENTROPIC ASCENT/OVERRUNNING SITUATION NW
OF THE FRONT THAT THEN STALLS OUT TO OUR SE. THIS FRONT WILL BE
AWAITING THE NEXT UPPER WAVE EXPECTED TO DIVE INTO THE SRN PLAINS
AROUND 12Z SUN BEFORE LIFTING NE TOWARD THE LOWER GREAT LAKES. THIS
WAVE WILL BRING ANOTHER ROUND OF SNOW ACROSS THE WARNING AREA SUN
AFTERNOON AND EVENING.
ONCE THE SYSTEM SNOW MOVES OUT SUN EVENING...WE WILL SEE NW FLOW
LAKE EFFECT BECOME ESTABLISHED WITH THE EXTREMELY COLD ARCTIC AIR
THAT WILL SPREAD ACROSS THE AREA.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 330 AM EST SAT JAN 4 2014
THE MAIN EMPHASIS IN THE LONG TERM CONTINUES TO BE ON THE BRUTALLY
COLD AIR MASS SWEEPING ACROSS MICHIGAN ON MONDAY AND TUESDAY. WIND
CHILLS ARE EXPECTED TO BE AROUND -25 OVER MOST OF THE AREA HOWEVER
VALUES ALONG THE I-94 CORRIDOR EAST OF KALAMAZOO MAY REACH AS LOW AS
-35 OR -40 MONDAY NIGHT WHERE A LK MI INFLUENCE PROBABLY WILL NOT BE
PRESENT AS SFC WINDS BECOME SOUTHWEST.
IN ADDITION TO THE SEVERE WIND CHILL READINGS... LAKE EFFECT SNOW
AND BLOWING SNOW WILL IMPACT THE AREA MONDAY AND TUESDAY.
ACCUMULATIONS WILL BE HELD DOWN DUE TO SMALL CRYSTAL SIZE BUT
VISIBILITIES SHOULD STILL BE GREATLY REDUCED AND ROADS WILL BE ICY
SINCE ROAD CHEMICALS WILL BE INEFFECTIVE WITH THE VERY COLD TEMPS.
THE REALLY COLD SFC AIR OF -10 TO -15 CURLING AROUND THE BOTTOM OF
LK MI INTO THE I-94 CORRIDOR REGION WILL LIKELY RESULT IN A NICE LOW
LEVEL CONVERGENCE/FGEN ZONE FOR THE LAKE EFFECT SNOW. A LENGTHY
EASTWARD/INLAND EXTENSION OF LAKE EFFECT SHOULD SET UP NEAR OR JUST
SOUTH OF THE I-96 CORRIDOR MONDAY NIGHT AND TUESDAY.
THE CORE OF THE COLDEST AIR LIFTS OUT TUESDAY NIGHT AND A MODERATING
TREND IN TEMPS IS EXPECTED FOR MID TO LATE WEEK. HIGHS BY FRIDAY
SHOULD BE UP NEAR 30. HOWEVER MORE LIGHT SNOW IS POSSIBLE WEDNESDAY
AND THURSDAY DUE TO WEAK WARM ADVECTION/ISENTROPIC LIFT PATTERN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 655 AM EST SAT JAN 4 2014
IFR CONDITIONS IN SNOW AND BLOWING SNOW ARE EXPECTED TO DEVELOP AT
MKG BY NOON THEN CONTINUE THIS AFTERNOON BEFORE LETTING UP SOME
TONIGHT. CONDITIONS AT MKG SHOULD THEN TRANSITION TO MVFR THIS
EVENING AND THE STRONG SOUTHWEST WINDS CURRENTLY GUSTING TO 40 KTS
WILL DIMINISH CONSIDERABLY BY THAT TIME AS WELL.
GRR SHOULD ALSO SEE IFR CONDITIONS IN SNOW DEVELOPING THIS
AFTERNOON...THEN CONTINUING TONIGHT.
SOUTH AND EAST OF GRR... SNOW SHOULD HOLD OFF UNTIL AFTER 00Z
TONIGHT WITH IFR SNOW DEVELOPING AFTER 06Z AT AZO/BTL/LAN/JXN.
MUCH OF TODAY WILL ACTUALLY REMAIN VFR SOUTH AND EAST OF GRR WITH
SOUTHWEST WINDS GUSTING TO 30 KTS. WINDS EVERYWHERE WILL DIMINISH
TO LESS THAN 10 KTS TONIGHT.
&&
.MARINE...
ISSUED AT 1051 AM EST SAT JAN 4 2014
I HAVE DOWNGRADED THE GALE WARNING TO A SMALL CRAFT ADVISORY SINCE
WINDS ARE DIMINISHING AS I WRITE THIS. WE MAY NEED A GALE WARNING
AND FREEZING SPRAY WARNING SUNDAY NIGHT INTO MONDAY BUT WILL NOT
ISSUE THAT JUST YET.
&&
.HYDROLOGY...
ISSUED AT 315 PM EST FRI JAN 3 2014
A FLOOD ADVISORY IS IN EFFECT FOR THE FLAT RIVER AT SMYRNA. A
SUSPECTED ICE JAM UPSTREAM HAS CAUSED A SHARP RISE FOLLOWED BY A
SHARP DECLINE AT THE SMYRNA RIVER GAUGE. ICE JAMS CAN CAUSE RAPID
FLUCTUATIONS IN RIVER LEVELS.
RIVERS WILL CONTINUE GAINING ICE COVERAGE AND THICKNESS FOR THE
FORESEEABLE FUTURE. THOSE RIVERS THAT ICE OVER COMPLETELY WILL HAVE
A MINIMAL ICE JAM THREAT. RIVERS WITH JAGGED ICE BUILDUP ARE IN
DANGER OF EXPERIENCING JAMMING AND RAPID FLUCTUATIONS. 6 OR MORE
INCHES OF SNOW IS EXPECTED FOR SOUTHERN AND SOUTHEAST LOWER MICHIGAN
SATURDAY NIGHT THROUGH SUNDAY EVENING. A BLAST OF EXTREME COLD AIR
FOLLOWS THE SNOW ON SUNDAY NIGHT.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 1 AM EST
MONDAY FOR MIZ051-052-056>058-064.
WIND CHILL WATCH FROM LATE SUNDAY NIGHT THROUGH TUESDAY
AFTERNOON FOR MIZ037>040-043>046-050>052-056>059-064>067-
071>074.
WINTER STORM WARNING FROM 7 PM THIS EVENING TO 1 AM EST MONDAY
FOR MIZ059-065>067-071>074.
LM...SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
LMZ844>849.
&&
$$
UPDATE...WDM
SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...MEADE
AVIATION...MEADE
HYDROLOGY...EBW
MARINE...WDM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
710 AM EST SAT JAN 4 2014
.UPDATE...
ISSUED AT 709 AM EST SAT JAN 4 2014
EXTENDED GOING WINTER STORM WARNING FOR ALGER COUNTY THRU 15Z WITH
SGNFT RADAR ECHOES LINGERING OVER THAT AREA UNDER THE DPVA/H85-5
QVECTOR CNVGC AHEAD OF SHRTWV MOVING E INTO THE UPR LKS. LARGER
SCALE SUBSIDENCE/MID LVL DRYING IN THE WAKE OF THIS DISTURBANCE WL
CAUSE THE SN TO DIMINISH IN ALGER COUNTY BY LATE MRNG.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 505 AM EST SAT JAN 4 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW VIGOROUS SHRTWV
SHIFTING E FM MN INTO THE UPR GRT LKS. THIS DISTURBANCE IS REFLECTED
BY A SFC LO PRES TROF IN MN...WHILE ANOTHER WEAKER DISTURBANCE/LO
PRES IS SHIFTING THRU ONTARIO. ALTHOUGH THERE IS NO WELL DEFINED SFC
LO PRES CENTER...THE SHARP PRES GRADIENT BTWN THE GENERAL LO PRES
TROF TO THE W AND RETREATING SFC HI PRES OVER THE MID ATLANTIC
STATES IS SUPPORTING A VERY STRONG SW FLOW INTO THE UPR LKS...WITH
THE 00Z GRB RAOB SHOWING AN IMPRESSIVE SW WIND UP TO 70 KTS AT H85.
THE ISENTROPIC ASCENT ASSOCIATED WITH THIS STRONG SW FLOW SUPPORTED
A BAND OF HEAVIER SN THAT IMPACTED MAINLY THE NRN PORTION OF UPR MI
AS WELL AS AREAS DOWNWIND OF LK MI...WHERE THE FLOW OFF THE WATER
IN THE PRESENCE OF THE RETREATING ARCTIC AIRMASS ALLOWED FOR SGNFT
LK ENHANCEMENT/SN FALL RATES UP TO AN INCH PER HR. THE LLVL
DESTABILIZATION ALSO SHARPENED LLVL LAPSE RATES AND ALLOWED FOR SFC
WIND GUSTS NEAR THE BAY OF GREEN BAY/LK MI TO REACH AS HI AS 68 MPH
AT A SITE NEAR THOMPSON IN SCHOOLCRAFT COUNTY. THE AREA OF STRONGEST
LLVL WINDS/SHARPER ISENTROPIC ASCENT/SUPPORTING CENTER OF VIGOROUS
H85-5 QVECTOR CNVGC IS TENDING TO DRIFT E EARLY THIS MRNG...SO THE
SW WINDS/SN INTENSITY ARE DIMINSING A BIT. BUT ANOTHER AREA OF SN TO
THE W ASSOCIATED WITH THE DPVA/ACCOMPANYING DEEP LYR QVECTOR CNVGC
ACCOMPANYING THE MN SHRTWV IS TENDING TO PUSH BACK INTO THE AREA.
LOOKING FARTHER TO THE W...COLDER AIR IS PLOWING BACK INTO THE NRN
PLAINS BEHIND A COLD FNT SWEEPING THRU MN. AN EVEN COLDER ARCTIC
AIRMASS ASSOCIATED WITH ANOTHER SHRTWV DIGGING SEWD THRU
ALBERTA/SASKATCHEWAN IS APRCHG THE NRN PLAINS.
MAIN FCST CONCERNS IN THE SHORT TERM ARE POPS ASSOCIATED WITH APRCHG
MN SHRTWV AND THEN TEMPS/LES AS THE MUCH COLDER AIR UPSTREAM IN THE
WAKE OF THIS DISTURBANCE SURGES INTO THE UPR LKS.
TODAY...AREA OF DPVA/DEEP LYR QVECTOR CNVGC SUPPORTING THE AREA OF
WDSPREAD SN MOVING INTO THE WRN CWA EARLY THIS MRNG IS PROGGED TO
MOVE OUT OF THE ERN CWA BTWN 15Z-18Z...SO TRENDED SYNOPTIC SCALE
POPS DOWN W-E IN LINE WITH GOING FCST WITH ARRIVAL OF DNVA/CAD/DEEP
LYR QVECTOR DVGC AND STRONG SUBSIDENCE/MID LVL DRYING IN THE WAKE OF
MN SHRTWV PASSAGE. BUT OVER THE W...LES WL DVLP IN THE COLD NW FLOW
BEHIND THE FROPA AS H85 TEMPS FALL TOWARD -18C BY 00Z SUN.
HOWEVER...FCST SUBSIDENCE IS PROGGED TO DROP THE INVRN BASE TO AS LO
AS 3-4K FT. NAM/GFS/LOCAL WRF ARW FCST SNGS ALSO INDICATE GENERAL
SUBSIDENCE IN THE MIXED LYR BLO THE INVRN...SO LES AMOUNTS SHOULD BE
RELATIVELY LGT. HI RES MODELS INDICATE THE MORE FOCUSED LLVL CNVGC
WL IMPACT NRN ONTONAGON/SRN HOUGHTON COUNTY. ALTHOUGH TEMPS WL RISE
INTO THE 20S THIS MRNG BEFORE SFC COLD FNT NOW IN MN CLEARS THE CWA
W-E AND NEWBERRY IN THE AFTN...TEMPS WL FALL W-E FOLLOWING THE FROPA
WITH THE ARRIVAL OF THE COLDER H85 TEMPS.
TNGT...COLDER AIR ASSOCIATED WITH DIGGING SHRTWV IN WRN CANADA/
DEEPENING ARCTIC BRANCH IN THE PLAINS IS PROGGED TO STEADILY ADVECT
INTO THE UPR GRT LKS IN STEADY WNW FLOW/H925 WINDS 20-25KTS.
CONSENSUS OF FAVORED MODELS INDICATES H85 TEMPS WL FALL TO ARND -25C
OVER THE WRN CWA AND -18C OVER THE E BY 12Z SUN. ALTHOUGH THIS CHILL
WITH H85/LK WATER TEMP DIFFERENCE OVER 20C WL SUPPORT LES... HIER
RES MODELS ARE INDICATING LO INVRN BASE MAINTAINED BY ONGOING
SUBIDENCE THAT EXTENDS INTO THE MIXED LYR WL HAMPER LES AMOUNTS. SO
A RELATIVELY HI POP/LO QPF SCENARIO SEEMS TO BE IN STORE. THE
ARRIVING CHILL WL ALSO PUSH THE DGZ BLO THE SFC OVER THE WRN CWA...
SO THIS POOR SN GROWTH WL ALSO HAMPER LES AMOUNTS. BUT THE SMALL SN
FLAKE SIZE WL BE EFFICIENT AT REDUCING VSBY...ESPECIALLY AT EXPOSED
LOCATIONS NEAR LK SUP. EXPECT TEMPS OVER THE INTERIOR W HALF...WHERE
THE INCOMING AIRMASS WL BE MODIFIED LEAST BY THE WARMING OF LK
SUP...TO FALL AS LO AS 15 TO 20 BLO ZERO. WITH APRNT TEMPS LIKELY TO
FALL TO -25 TO -35...OPTED TO ISSUE A WIND CHILL ADVY FOR LATE TNGT
THRU SUN MRNG FOR THE INTERIOR W HALF COUNTIES EVEN THOUGH WIND
SPEEDS MAY NOT HOLD AOA THE THRESHOLD OF 10 MPH.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 505 AM EST SAT JAN 4 2014
...WIND CHILL WATCH ISSUED FOR SUNDAY NIGHT THROUGH LATE TUESDAY
MORNING...
A CLOSED 500MB LOW WILL SETTLE OVER THE GREAT LAKES SUNDAY INTO
MONDAY NIGHT...AND THEN MOVE INTO ONTARIO AND QUEBEC TUESDAY INTO
WEDNESDAY. UPPER MICHIGAN WILL REMAIN UNDER RATHER ZONAL FLOW ALOFT
FROM TUESDAY INTO WEDNESDAY AS THE LOW DEPARTS...AND THEN ANOTHER
TROUGH WILL SWING THROUGH AGAIN ON THURSDAY AS A RIDGE BUILDS OVER
THE NORTHERN PLAINS. AT THE SURFACE...THE LOW RESPONSIBLE FOR THE
EARLY WEEKEND SNOW OVER UPPER MI WILL MOVE INTO JAMES BAY SUNDAY
MORNING. THIS WILL ALLOW A VERY COLD ARCTIC AIRMASS OVER THE
CANADIAN PRAIRIE TO SINK INTO THE MIDWEST FOR SUNDAY AND MONDAY.
MEANWHILE...LOW PRESSURE DEVELOPING IN THE CENTRAL PLAINS SUNDAY
AFTERNOON WILL MOVE NORTHEASTWARD INTO THE LOWER LAKES BY MONDAY
MORNING...AND INTO ONTARIO BY MONDAY EVENING. THIS WILL ALLOW THE
ARCTIC AIRMASS TO FULLY INFILTRATE UPPER MICHIGAN SUNDAY NIGHT INTO
WEDNESDAY...BRINGING SOME OF THE COLDEST TEMPERATURES OF THE SEASON.
MODELS ARE CONSISTENT IN HAVING 850MB TEMPS RANGING FROM -28C TO
-35C CREEPING INTO THE WESTERN CWA STARTING LATE SUNDAY
AFTERNOON...AND THEN SLIDING OVER THE REST OF THE CWA THROUGH
TUESDAY. OVERALL...EXPECT SUNDAY NIGHT LOW TEMPERATURES TO RANGE
FROM -29F TO AROUND -3F ACROSS THE FORECAST AREA...WITH THE COLDEST
TEMPERATURES FAR WEST NEAR THE WI BORDER. HIGH TEMPERATURES ON
MONDAY WILL ONLY REBOUND TO NEAR -13F OUT WEST...AND INTO THE SINGLE
DIGITS ABOVE ZERO IN THE EAST. TEMPERATURES MONDAY NIGHT WILL RANGE
FROM -27F OUT WEST...AND -14C OUT EAST. AREAS NEAR THE LAKESHORE
WILL BE IN THE SINGLE DIGITS BELOW ZERO. AS PREVIOUS STATEMENTS AND
DISCUSSIONS HAVE MENTIONED...THIS IS THE COLDEST AIR MASS SINCE
PERHAPS THE INTENSE COLD WAVE OF EARLY FEBRUARY 1996.
TO WORSEN MATTERS...THE TIGHT PRESSURE GRADIENT BETWEEN THE INCOMING
HIGH AND THE LOW PRESSURE MOVING OVER THE LOWER LAKES WILL KEEP
WEST-NORTHWEST WINDS GUSTING OVER THE CWA THROUGH SUNDAY NIGHT
THROUGH TUESDAY NIGHT...WHICH WILL LEAD TO DANGEROUSLY COLD WIND
CHILLS...EVEN DURING THE DAY. AREAS ACROSS THE INLAND WEST WILL SEE
WIND CHILL VALUES AS LOW AS -50F DURING THE OVERNIGHT
HOURS...WHEREAS THE REMAINDER OF THE AREA WILL SEE VALUES RANGING
FROM -40F TO -20F. HAVE ISSUED A WIND CHILL WATCH FOR SUNDAY NIGHT
INTO MONDAY MORNING ACROSS THE WEST ACCORDINGLY...WHERE WIND CHILL
VALUES ARE EXPECTED TO REMAIN CRITICAL THROUGH A MAJORITY OF THE
PERIOD. DELAYED THE WATCH FOR THE EASTERN HALF UNTIL MONDAY
NIGHT...AS VALUES ARE NOT EXPECTED TO STEADILY REACH WIND CHILL
WARNING CRITERIA UNTIL THEN. SEE THE LATEST WINTER WEATHER MESSAGE
FOR ADDITIONAL DETAILS AND PRECAUTIONARY MEASURES.
AS FAR AS PRECIPITATION SUNDAY INTO TUESDAY GOES...WITH VERY COLD
TEMPERATURES AND WEST-NORTHWEST WINDS THROUGH THE TIME PERIOD/AN
UPPER LEVEL LOW ALOFT/ EXPECT LES TO DEVELOP AND PERSIST IN FAVORED
SNOWBELTS ACROSS MICHIGAN. THE LIMITING FACTOR...AS WE HAVE SEEN IN
THE PAST FEW WEEKS WITH COLDER TEMPS...WILL BE THE SNOW RATIOS AS
THE DGZ PLUMMETS INTO THE GROUND. OVERALL...THINKING THE 15-17:1
RATIOS ARE REASONABLE AS LAST WEEKS SNOW TOTALS DURING THE COLDER
TEMPS WERE IN THIS RANGE. WHILE SNOW TOTALS ARE NOT EXPECTED TO BE
TOO IMPRESSIVE...GUSTY WINDS WILL LEAD TO AREAS OF BLOWING
SNOW...ESPECIALLY MONDAY INTO TUESDAY. TOTALS IN WNW-FAVORED
SNOWBELTS ALONG LAKE SUPERIOR ARE EXPECTED TO BE AROUND 1 TO 3
INCHES THROUGH MONDAY MORNING...AND THEN 2 TO 5 INCHES MONDAY
MORNING INTO TUESDAY MORNING...WITH THE HIGHEST ACCUMULATIONS
EXPECTED EAST OF MUNISING. ADVISORIES MAY BE NEEDED IN AREAS WITH
THE MOST ACCUMULATIONS/MOST BLOWING SNOW LATER THIS WEEK...SO STAY
TUNED FOR THE LATEST.
OTHERWISE...HIGH PRESSURE KEEPS THINGS FAIRLY QUIET FOR WEDNESDAY
INTO THURSDAY...AND KEEPS WINDS LIGHTER. LOW PRESSURE WILL MOVE FROM
NORTHERN MANITOBA THURSDAY INTO JAMES BAY BY SATURDAY...WHICH WILL
BRING SOUTH-SOUTHWESTERLY FLOW ACROSS UPPER MICHIGAN ALONG WITH
WARMER AIR...THANKFULLY. HIGH TEMPERATURES WILL REBOUND INTO THE
TEENS AND 20S STARTING THURSDAY...AND REMAINING LES FOR
WEST-NORTHWEST WIND FAVORED SNOWBELTS WILL MOVE OFFSHORE INTO LAKE
SUPERIOR.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 709 AM EST SAT JAN 4 2014
CMX...EXPECT IFR CONDITIONS TO PREVAIL THIS FCST PERIOD WITH LGT SN
IN ADVANCE OF AN APRCHG COLD FNT GIVING WAY TO LK EFFECT SHSN/BLSN
FOLLOWING THE FROPA THIS MRNG. ALTHOUGH STRONG SUBSIDENCE AND SOME
DRIER AIR WL FOLLOW THE FROPA...UPSLOPE GUSTY W WIND WITH ARRIVAL OF
MUCH COLDER AIR WL SUPPORT PERSISTENT LK EFFECT -SHSN/BLSN OF SMALL
FLAKES THAT ARE EFFICIENT AT REDUCING VSBY AND IFR CONDITIONS THRU
THE ENTIRE FCST PERIOD.
IWD...ALTHOUGH SOME SN/IFR VSBYS MAY IMPACT THIS SITE THIS MRNG
COINCIDENT WITH A COLD FROPA...EXPECT MVFR CONDITIONS TO PREDOMINATE
WITH SOME LK EFFECT -SHSN FOLLOWING THE FROPA.
SAW...EXPECT MVFR CONDITIONS WITH SOME -SN IN ADVANCE OF A COLD FNT
THIS MRNG. THERE SHOULD BE ENUF DRYING/SUBSIDENCE TO CAUSE
CONDITIONS TO IMPROVE TO VFR LATER TDAY/TNG IN THE PRESENCE OF A
DOWNSLOPE WNW FLOW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 505 AM EST SAT JAN 4 2014
SW GALES AHEAD OF AN APPROACHING COLD FRONT OVER EASTERN LAKE
SUPERIOR WILL DIMINISH THIS MORNING WITH THE ARRIVAL OF A WEAKER
PRES GRADIENT. IT NOW APPEARS THE NW WINDS BEHIND THE FRONT WL NOT
BE AS STRONG AS EARLIER ANTICIPATED AND NOT REACH GALE THRESHOLDS
EXCEPT PERHAPS OVER THE E PART OF THE LAKE THIS AFTERNOON. SO OPTED
TO CANX THE GOING GALE WARNING FOR ALL BUT THAT AREA. DID SHORTERN
THE WARNING FOR THE E THIS EVENING SINCE THE MARGINAL GALES THERE
WILL DIMINISH BY THEN. EVEN THOUGH THE NW WINDS WILL BE UP TO ONLY
25-30 KTS INSTEAD OF 35 KTS THRU TONIGHT...THE ARRIVAL OF BITTERLY
COLD ARCTIC AIR/SUFFICIENTLY HI WAVES WILL RESULT IN WIDESPREAD
HEAVY FREEZING SPRAY...ESPECIALLY THIS AFTERNOON AND TONIGHT.
WEST TO NORTHWEST WINDS OF 15 TO 25 KNOTS WILL CONTINUE FROM SUNDAY
INTO MONDAY MORNING. THE TIGHTENING PRESSURE GRADIENT BETWEEN LOW
PRESSURE OVER THE NEW ENGLAND STATES AND INCOMING HIGH PRESSURE FROM
THE NORTHERN PLAINS WILL BRING NORTHWEST GALES TO 40 KNOTS TO MAINLY
CENTRAL AND EASTERN LAKE SUPERIOR MONDAY AFTERNOON INTO TUESDAY
EVENING. HIGH PRESSURE WILL RETURN WEDNESDAY INTO THURSDAY AND BRING
WINDS DOWN BELOW 20 KNOTS. APPROACHING LOW PRESSURE WILL BRING
SOUTHERLY WINDS 15 TO 25 KNOTS TO LAKE SUPERIOR FOR FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL WATCH FROM SUNDAY EVENING THROUGH TUESDAY MORNING FOR
MIZ001>005-009>013-084.
WIND CHILL ADVISORY FROM MIDNIGHT EST /11 PM CST/ TONIGHT TO
NOON EST /11 AM CST/ SUNDAY FOR MIZ002-004-005-009>013-084.
WINTER STORM WARNING UNTIL NOON EST TODAY FOR MIZ007-014-085.
WIND CHILL WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING FOR
MIZ006-007-014-085.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR MIZ001-
003.
WINTER STORM WARNING UNTIL 10 AM EST THIS MORNING FOR MIZ006.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ266-267.
HEAVY FREEZING SPRAY WARNING UNTIL 4 AM EST /3 AM CST/ TUESDAY
FOR LSZ162-263>266.
HEAVY FREEZING SPRAY WARNING FROM 1 PM THIS AFTERNOON TO 7 AM
EST MONDAY FOR LSZ249>251.
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST MONDAY FOR
LSZ243>245-248.
LAKE MICHIGAN...
HEAVY FREEZING SPRAY WARNING UNTIL 10 AM EST THIS MORNING FOR
LMZ248-250.
GALE WARNING UNTIL 1 PM EST THIS AFTERNOON FOR LMZ221-248-250.
&&
$$
UPDATE...KC
SHORT TERM...KC
LONG TERM...MCD
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
511 AM EST SAT JAN 4 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 505 AM EST SAT JAN 4 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW VIGOROUS SHRTWV
SHIFTING E FM MN INTO THE UPR GRT LKS. THIS DISTURBANCE IS REFLECTED
BY A SFC LO PRES TROF IN MN...WHILE ANOTHER WEAKER DISTURBANCE/LO
PRES IS SHIFTING THRU ONTARIO. ALTHOUGH THERE IS NO WELL DEFINED SFC
LO PRES CENTER...THE SHARP PRES GRADIENT BTWN THE GENERAL LO PRES
TROF TO THE W AND RETREATING SFC HI PRES OVER THE MID ATLANTIC
STATES IS SUPPORTING A VERY STRONG SW FLOW INTO THE UPR LKS...WITH
THE 00Z GRB RAOB SHOWING AN IMPRESSIVE SW WIND UP TO 70 KTS AT H85.
THE ISENTROPIC ASCENT ASSOCIATED WITH THIS STRONG SW FLOW SUPPORTED
A BAND OF HEAVIER SN THAT IMPACTED MAINLY THE NRN PORTION OF UPR MI
AS WELL AS AREAS DOWNWIND OF LK MI...WHERE THE FLOW OFF THE WATER
IN THE PRESENCE OF THE RETREATING ARCTIC AIRMASS ALLOWED FOR SGNFT
LK ENHANCEMENT/SN FALL RATES UP TO AN INCH PER HR. THE LLVL
DESTABILIZATION ALSO SHARPENED LLVL LAPSE RATES AND ALLOWED FOR SFC
WIND GUSTS NEAR THE BAY OF GREEN BAY/LK MI TO REACH AS HI AS 68 MPH
AT A SITE NEAR THOMPSON IN SCHOOLCRAFT COUNTY. THE AREA OF STRONGEST
LLVL WINDS/SHARPER ISENTROPIC ASCENT/SUPPORTING CENTER OF VIGOROUS
H85-5 QVECTOR CNVGC IS TENDING TO DRIFT E EARLY THIS MRNG...SO THE
SW WINDS/SN INTENSITY ARE DIMINSING A BIT. BUT ANOTHER AREA OF SN TO
THE W ASSOCIATED WITH THE DPVA/ACCOMPANYING DEEP LYR QVECTOR CNVGC
ACCOMPANYING THE MN SHRTWV IS TENDING TO PUSH BACK INTO THE AREA.
LOOKING FARTHER TO THE W...COLDER AIR IS PLOWING BACK INTO THE NRN
PLAINS BEHIND A COLD FNT SWEEPING THRU MN. AN EVEN COLDER ARCTIC
AIRMASS ASSOCIATED WITH ANOTHER SHRTWV DIGGING SEWD THRU
ALBERTA/SASKATCHEWAN IS APRCHG THE NRN PLAINS.
MAIN FCST CONCERNS IN THE SHORT TERM ARE POPS ASSOCIATED WITH APRCHG
MN SHRTWV AND THEN TEMPS/LES AS THE MUCH COLDER AIR UPSTREAM IN THE
WAKE OF THIS DISTURBANCE SURGES INTO THE UPR LKS.
TODAY...AREA OF DPVA/DEEP LYR QVECTOR CNVGC SUPPORTING THE AREA OF
WDSPREAD SN MOVING INTO THE WRN CWA EARLY THIS MRNG IS PROGGED TO
MOVE OUT OF THE ERN CWA BTWN 15Z-18Z...SO TRENDED SYNOPTIC SCALE
POPS DOWN W-E IN LINE WITH GOING FCST WITH ARRIVAL OF DNVA/CAD/DEEP
LYR QVECTOR DVGC AND STRONG SUBSIDENCE/MID LVL DRYING IN THE WAKE OF
MN SHRTWV PASSAGE. BUT OVER THE W...LES WL DVLP IN THE COLD NW FLOW
BEHIND THE FROPA AS H85 TEMPS FALL TOWARD -18C BY 00Z SUN.
HOWEVER...FCST SUBSIDENCE IS PROGGED TO DROP THE INVRN BASE TO AS LO
AS 3-4K FT. NAM/GFS/LOCAL WRF ARW FCST SNGS ALSO INDICATE GENERAL
SUBSIDENCE IN THE MIXED LYR BLO THE INVRN...SO LES AMOUNTS SHOULD BE
RELATIVELY LGT. HI RES MODELS INDICATE THE MORE FOCUSED LLVL CNVGC
WL IMPACT NRN ONTONAGON/SRN HOUGHTON COUNTY. ALTHOUGH TEMPS WL RISE
INTO THE 20S THIS MRNG BEFORE SFC COLD FNT NOW IN MN CLEARS THE CWA
W-E AND NEWBERRY IN THE AFTN...TEMPS WL FALL W-E FOLLOWING THE FROPA
WITH THE ARRIVAL OF THE COLDER H85 TEMPS.
TNGT...COLDER AIR ASSOCIATED WITH DIGGING SHRTWV IN WRN CANADA/
DEEPENING ARCTIC BRANCH IN THE PLAINS IS PROGGED TO STEADILY ADVECT
INTO THE UPR GRT LKS IN STEADY WNW FLOW/H925 WINDS 20-25KTS.
CONSENSUS OF FAVORED MODELS INDICATES H85 TEMPS WL FALL TO ARND -25C
OVER THE WRN CWA AND -18C OVER THE E BY 12Z SUN. ALTHOUGH THIS CHILL
WITH H85/LK WATER TEMP DIFFERENCE OVER 20C WL SUPPORT LES... HIER
RES MODELS ARE INDICATING LO INVRN BASE MAINTAINED BY ONGOING
SUBIDENCE THAT EXTENDS INTO THE MIXED LYR WL HAMPER LES AMOUNTS. SO
A RELATIVELY HI POP/LO QPF SCENARIO SEEMS TO BE IN STORE. THE
ARRIVING CHILL WL ALSO PUSH THE DGZ BLO THE SFC OVER THE WRN CWA...
SO THIS POOR SN GROWTH WL ALSO HAMPER LES AMOUNTS. BUT THE SMALL SN
FLAKE SIZE WL BE EFFICIENT AT REDUCING VSBY...ESPECIALLY AT EXPOSED
LOCATIONS NEAR LK SUP. EXPECT TEMPS OVER THE INTERIOR W HALF...WHERE
THE INCOMING AIRMASS WL BE MODIFIED LEAST BY THE WARMING OF LK
SUP...TO FALL AS LO AS 15 TO 20 BLO ZERO. WITH APRNT TEMPS LIKELY TO
FALL TO -25 TO -35...OPTED TO ISSUE A WIND CHILL ADVY FOR LATE TNGT
THRU SUN MRNG FOR THE INTERIOR W HALF COUNTIES EVEN THOUGH WIND
SPEEDS MAY NOT HOLD AOA THE THRESHOLD OF 10 MPH.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 505 AM EST SAT JAN 4 2014
...WIND CHILL WATCH ISSUED FOR SUNDAY NIGHT THROUGH LATE TUESDAY
MORNING...
A CLOSED 500MB LOW WILL SETTLE OVER THE GREAT LAKES SUNDAY INTO
MONDAY NIGHT...AND THEN MOVE INTO ONTARIO AND QUEBEC TUESDAY INTO
WEDNESDAY. UPPER MICHIGAN WILL REMAIN UNDER RATHER ZONAL FLOW ALOFT
FROM TUESDAY INTO WEDNESDAY AS THE LOW DEPARTS...AND THEN ANOTHER
TROUGH WILL SWING THROUGH AGAIN ON THURSDAY AS A RIDGE BUILDS OVER
THE NORTHERN PLAINS. AT THE SURFACE...THE LOW RESPONSIBLE FOR THE
EARLY WEEKEND SNOW OVER UPPER MI WILL MOVE INTO JAMES BAY SUNDAY
MORNING. THIS WILL ALLOW A VERY COLD ARCTIC AIRMASS OVER THE
CANADIAN PRAIRIE TO SINK INTO THE MIDWEST FOR SUNDAY AND MONDAY.
MEANWHILE...LOW PRESSURE DEVELOPING IN THE CENTRAL PLAINS SUNDAY
AFTERNOON WILL MOVE NORTHEASTWARD INTO THE LOWER LAKES BY MONDAY
MORNING...AND INTO ONTARIO BY MONDAY EVENING. THIS WILL ALLOW THE
ARCTIC AIRMASS TO FULLY INFILTRATE UPPER MICHIGAN SUNDAY NIGHT INTO
WEDNESDAY...BRINGING SOME OF THE COLDEST TEMPERATURES OF THE SEASON.
MODELS ARE CONSISTENT IN HAVING 850MB TEMPS RANGING FROM -28C TO
-35C CREEPING INTO THE WESTERN CWA STARTING LATE SUNDAY
AFTERNOON...AND THEN SLIDING OVER THE REST OF THE CWA THROUGH
TUESDAY. OVERALL...EXPECT SUNDAY NIGHT LOW TEMPERATURES TO RANGE
FROM -29F TO AROUND -3F ACROSS THE FORECAST AREA...WITH THE COLDEST
TEMPERATURES FAR WEST NEAR THE WI BORDER. HIGH TEMPERATURES ON
MONDAY WILL ONLY REBOUND TO NEAR -13F OUT WEST...AND INTO THE SINGLE
DIGITS ABOVE ZERO IN THE EAST. TEMPERATURES MONDAY NIGHT WILL RANGE
FROM -27F OUT WEST...AND -14C OUT EAST. AREAS NEAR THE LAKESHORE
WILL BE IN THE SINGLE DIGITS BELOW ZERO. AS PREVIOUS STATEMENTS AND
DISCUSSIONS HAVE MENTIONED...THIS IS THE COLDEST AIR MASS SINCE
PERHAPS THE INTENSE COLD WAVE OF EARLY FEBRUARY 1996.
TO WORSEN MATTERS...THE TIGHT PRESSURE GRADIENT BETWEEN THE INCOMING
HIGH AND THE LOW PRESSURE MOVING OVER THE LOWER LAKES WILL KEEP
WEST-NORTHWEST WINDS GUSTING OVER THE CWA THROUGH SUNDAY NIGHT
THROUGH TUESDAY NIGHT...WHICH WILL LEAD TO DANGEROUSLY COLD WIND
CHILLS...EVEN DURING THE DAY. AREAS ACROSS THE INLAND WEST WILL SEE
WIND CHILL VALUES AS LOW AS -50F DURING THE OVERNIGHT
HOURS...WHEREAS THE REMAINDER OF THE AREA WILL SEE VALUES RANGING
FROM -40F TO -20F. HAVE ISSUED A WIND CHILL WATCH FOR SUNDAY NIGHT
INTO MONDAY MORNING ACROSS THE WEST ACCORDINGLY...WHERE WIND CHILL
VALUES ARE EXPECTED TO REMAIN CRITICAL THROUGH A MAJORITY OF THE
PERIOD. DELAYED THE WATCH FOR THE EASTERN HALF UNTIL MONDAY
NIGHT...AS VALUES ARE NOT EXPECTED TO STEADILY REACH WIND CHILL
WARNING CRITERIA UNTIL THEN. SEE THE LATEST WINTER WEATHER MESSAGE
FOR ADDITIONAL DETAILS AND PRECAUTIONARY MEASURES.
AS FAR AS PRECIPITATION SUNDAY INTO TUESDAY GOES...WITH VERY COLD
TEMPERATURES AND WEST-NORTHWEST WINDS THROUGH THE TIME PERIOD/AN
UPPER LEVEL LOW ALOFT/ EXPECT LES TO DEVELOP AND PERSIST IN FAVORED
SNOWBELTS ACROSS MICHIGAN. THE LIMITING FACTOR...AS WE HAVE SEEN IN
THE PAST FEW WEEKS WITH COLDER TEMPS...WILL BE THE SNOW RATIOS AS
THE DGZ PLUMMETS INTO THE GROUND. OVERALL...THINKING THE 15-17:1
RATIOS ARE REASONABLE AS LAST WEEKS SNOW TOTALS DURING THE COLDER
TEMPS WERE IN THIS RANGE. WHILE SNOW TOTALS ARE NOT EXPECTED TO BE
TOO IMPRESSIVE...GUSTY WINDS WILL LEAD TO AREAS OF BLOWING
SNOW...ESPECIALLY MONDAY INTO TUESDAY. TOTALS IN WNW-FAVORED
SNOWBELTS ALONG LAKE SUPERIOR ARE EXPECTED TO BE AROUND 1 TO 3
INCHES THROUGH MONDAY MORNING...AND THEN 2 TO 5 INCHES MONDAY
MORNING INTO TUESDAY MORNING...WITH THE HIGHEST ACCUMULATIONS
EXPECTED EAST OF MUNISING. ADVISORIES MAY BE NEEDED IN AREAS WITH
THE MOST ACCUMULATIONS/MOST BLOWING SNOW LATER THIS WEEK...SO STAY
TUNED FOR THE LATEST.
OTHERWISE...HIGH PRESSURE KEEPS THINGS FAIRLY QUIET FOR WEDNESDAY
INTO THURSDAY...AND KEEPS WINDS LIGHTER. LOW PRESSURE WILL MOVE FROM
NORTHERN MANITOBA THURSDAY INTO JAMES BAY BY SATURDAY...WHICH WILL
BRING SOUTH-SOUTHWESTERLY FLOW ACROSS UPPER MICHIGAN ALONG WITH
WARMER AIR...THANKFULLY. HIGH TEMPERATURES WILL REBOUND INTO THE
TEENS AND 20S STARTING THURSDAY...AND REMAINING LES FOR
WEST-NORTHWEST WIND FAVORED SNOWBELTS WILL MOVE OFFSHORE INTO LAKE
SUPERIOR.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1247 AM EST SAT JAN 4 2014
CMX...EXPECT IFR CONDITIONS TO PREVAIL THIS FCST PERIOD WITH LGT SN
IN ADVANCE OF AN APRCHG COLD FNT. ALTHOUGH SOME DRIER AIR WL FOLLOW
THE FROPA THIS MRNG...UPSLOPE GUSTY W WIND WITH ARRIVAL OF MUCH
COLDER AIR WL SUPPORT PERSISTENT LK EFFECT -SHSN/BLSN AND THE IFR
CONDITIONS.
IWD...ALTHOUGH SOME SN/LOWER IFR VSBYS WL IMPACT THIS SITE THIS MRNG
COINCIDENT WITH A COLD FROPA...EXPECT PREDOMINANT MVFR CONDITIONS TO
PREDOMINATE WITH SOME LK EFFECT -SHSN FOLLOWING THE FROPA.
SAW...EXPECT INTERMITTENT IFR CONDITIONS EARLY IN THE FCST PERIOD
WITH SN/BLSN TO GIVE WAY TO MVFR CONDITIONS WITH SOME DRYING ALF.
FOLLOWING A COLD FROPA LATER THIS MRNG...THE ARRIVAL OF DRIER AIR
WITH A DOWNSLOPE WNW FLOW WL CAUSE CONDITIONS TO IMPROVE TO VFR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 505 AM EST SAT JAN 4 2014
SW GALES AHEAD OF AN APPROACHING COLD FRONT OVER EASTERN LAKE
SUPERIOR WILL DIMINISH THIS MORNING WITH THE ARRIVAL OF A WEAKER
PRES GRADIENT. IT NOW APPEARS THE NW WINDS BEHIND THE FRONT WL NOT
BE AS STRONG AS EARLIER ANTICIPATED AND NOT REACH GALE THRESHOLDS
EXCEPT PERHAPS OVER THE E PART OF THE LAKE THIS AFTERNOON. SO OPTED
TO CANX THE GOING GALE WARNING FOR ALL BUT THAT AREA. DID SHORTERN
THE WARNING FOR THE E THIS EVENING SINCE THE MARGINAL GALES THERE
WILL DIMINISH BY THEN. EVEN THOUGH THE NW WINDS WILL BE UP TO ONLY
25-30 KTS INSTEAD OF 35 KTS THRU TONIGHT...THE ARRIVAL OF BITTERLY
COLD ARCTIC AIR/SUFFICIENTLY HI WAVES WILL RESULT IN WIDESPREAD
HEAVY FREEZING SPRAY...ESPECIALLY THIS AFTERNOON AND TONIGHT.
WEST TO NORTHWEST WINDS OF 15 TO 25 KNOTS WILL CONTINUE FROM SUNDAY
INTO MONDAY MORNING. THE TIGHTENING PRESSURE GRADIENT BETWEEN LOW
PRESSURE OVER THE NEW ENGLAND STATES AND INCOMING HIGH PRESSURE FROM
THE NORTHERN PLAINS WILL BRING NORTHWEST GALES TO 40 KNOTS TO MAINLY
CENTRAL AND EASTERN LAKE SUPERIOR MONDAY AFTERNOON INTO TUESDAY
EVENING. HIGH PRESSURE WILL RETURN WEDNESDAY INTO THURSDAY AND BRING
WINDS DOWN BELOW 20 KNOTS. APPROACHING LOW PRESSURE WILL BRING
SOUTHERLY WINDS 15 TO 25 KNOTS TO LAKE SUPERIOR FOR FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL WATCH FROM SUNDAY EVENING THROUGH TUESDAY MORNING FOR
MIZ001>005-009>013-084.
WIND CHILL ADVISORY FROM MIDNIGHT EST /11 PM CST/ TONIGHT TO
NOON EST /11 AM CST/ SUNDAY FOR MIZ002-004-005-009>013-084.
WINTER STORM WARNING UNTIL NOON EST TODAY FOR MIZ007-014-085.
WIND CHILL WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING FOR
MIZ006-007-014-085.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR MIZ001-
003.
WINTER STORM WARNING UNTIL 7 AM EST THIS MORNING FOR MIZ006.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ266-267.
HEAVY FREEZING SPRAY WARNING UNTIL 4 AM EST /3 AM CST/ TUESDAY
FOR LSZ162-263>266.
HEAVY FREEZING SPRAY WARNING FROM 1 PM THIS AFTERNOON TO 7 AM
EST MONDAY FOR LSZ249>251.
HEAVY FREEZING SPRAY WARNING FROM 10 AM THIS MORNING TO 7 AM EST
MONDAY FOR LSZ243>245-248.
LAKE MICHIGAN...
HEAVY FREEZING SPRAY WARNING UNTIL 10 AM EST THIS MORNING FOR
LMZ248-250.
GALE WARNING UNTIL 1 PM EST THIS AFTERNOON FOR LMZ221-248-250.
&&
$$
SHORT TERM...KC
LONG TERM...MCD
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
534 PM CST SUN JAN 5 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 305 PM CST SUN JAN 5 2014
NORTHWEST WINDS HAVE INCREASED SUBSTANTIALLY ACROSS WEST CENTRAL
THROUGH SOUTH CENTRAL MN THIS AFTERNOON WITH 20-25 KNOTS COMMON.
THIS IS OCCURRING AS THE CORE OF THE ARCTIC AIR ARRIVES ALONG WITH
THE PRESSURE GRADIENT TIGHTENING BETWEEN A LOW PRESSURE STORM SYSTEM
MOVING THROUGH THE OHIO VALLEY AND A 1053MB HIGH OVER MONTANA.
WEB CAMS ARE SHOWING BLOWING SNOW WITH 1 TO 2 MILE VISIBILITY IN
THE AFOREMENTIONED AREAS. THE BLOWING SNOW WILL CONTINUE THROUGH
THE EVENING ADDING ANOTHER ELEMENT OF DANGER TO THE ALREADY LOW
WINDS CHILLS OF -40 TO -45 CURRENTLY IN PLACE. SATELLITE IMAGERY
SHOWS SOME NICE CONVECTIVE ROLLS AS WELL IN THE MN RIVER VALLEY WITH
THE RAP INDICATING LOW LEVEL LAPSE RATES EXCEEDING 8 DEG C/KM.
LITTLE DEVIATION TO THE FORECAST LOWS/HIGHS FOR TONIGHT AND
MONDAY AS THE CORE OF THE ARCTIC VORTEX SWINGS THROUGH. MUCH OF
CENTRAL MN AND ALONG HIGHWAY 8 IN WEST CENTRAL WI EXPECTED TO
REACH -30 TO -35 WITH -25 TO -30 OVER THE REMAINDER OF THE FA.
HIGHS ON MONDAY PROGGED TO BE IN THE -13 TO -19 RANGE FROM SOUTH
TO NORTH. WIND CHILL VALUES OVERNIGHT AND MONDAY MORNING FROM -50
TO -65 WITH -40 TO -50 FOR MONDAY AFTERNOON.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 305 PM CST SUN JAN 5 2014
THE MAIN WX DISCUSSION IS THAT THE CORE OF THE COLDEST AIR WILL HAVE
MOVED OUT OF THE REGION BY MONDAY NIGHT WITH ONLY RESIDUAL AFFECTS
BASED ON WIND SPDS AND TEMPS STILL IN THE TEENS AND 20S BLW ZERO
THRU TUESDAY MORNING. AS HIGH PRESSURE MOVES OVERHEAD TUESDAY
NIGHT/WEDNESDAY...THE AFFECTS OF RADIATIONAL COOLING MAY AID IN SOME
LOWER TEMPS THAN CURRENTLY FORECAST. BASED ON CURRENT MODEL TRENDS
NEAR -20F IN THE NORTHERN CWA...TO THE SINGLE DIGITS BLW ZERO IN THE
SOUTHERN CWA SEEMS REASONABLE AT THIS TIME.
AFTER WEDNESDAY...THE JET STREAM WILL MOVE NORTH WITH A MORE ZONAL
FLOW DEVELOPING BY THE END OF THE WEEK. THIS WILL LEAD TO MUCH
WARMER TEMPS BY FRI/SAT/SUN WITH ABV NORMAL READINGS ALMOST LIKELY.
MODELS ARE STILL HAVING TROUBLE HANDLING THE SPLIT FLOW REGIME.
BASICALLY FOR OUR REGION IT MEANS THAT UNCERTAINTY EXISTS AS MODELS
ARE TRYING TO HOLD ONTO THE SOUTHERN JET AS THE MOST ACTIVE WX IN
THE NEXT 7 DAYS. CONFIDENCE WILL REMAIN LOW UNTIL MODELS HAVE A
BETTER HANDLE ON THE SOUTHERN JET STREAM STORM SYSTEM THAT WILL
AFFECT THE SOUTHERN U.S. NEXT WEEKEND. AS FOR OUR AREA...MAINLY DRY
WX WILL CONTINUE WITH A MUCH ANTICIPATED WARMING TREND AT LEAST IN
THE SHORT TERM AFTER WEDNESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 523 PM CST SUN JAN 5 2014
COLD CORE TROUGH WORKING EAST ACROSS MINNESOTA THIS EVENING. WERE
ABLE TO DEVELOP SOME ARCTIC STRATUS AND EVENING SOME IC/-SHSN/BLSN IN
LOWER LEVELS OF THE BOUNDARY LAYER THIS AFTERNOON/EVENING. LATEST
RADAR SHOWING THIS APPEARS TO BE WANING A BIT TO THE WEST. WILL
KEEP THE POSSIBILITY OF A FLURRY IN DURING THE EVENING. IS WINDS
RELAX ENOUGH...COULD SEE ANY SIGNIFICANT BLSN TO MOVE OUT THEN AS
WELL. WILL MENTION AT LEAST SOME MVFR CIGS THIS EVENING...PERHAPS
IFR IN THE KAXN/KRWF AREAS FOR A TIME THIS EVENING. AS THE TROUGH
EXITS TO THE EAST...COLDEST AIR ARRIVES AND WELL COULD SEE SOME
IC/IF SUNDOG/SUN PILLAR CONDITIONS AROUND SUNRISE MOST AREAS. WILL
HAVE TO MONITOR FOR THAT. OTHERWISE...NORTHWEST WINDS WILL BE
GUSTY INTO MONDAY...BEFORE RELAXING AROUND 06.00Z MOST AREAS ALONG
WITH VFR CONDITIONS.
KMSP...CLOUD STREETS/SNOW SHOWERS ON RADAR THIS EVENING...APPEARS
TO BE TAPERING OFF TO THE WEST. VSBYS WENT BLO 2SM -SHSN AT
KSGS...AND THAT SEEMS TO BE EXITING TO THE SOUTHEAST. EXPECT THEST
-SHSN TO END THROUGH 03Z AND THEN GO SKC OR TEMPO FEW010-015
OVERNIGHT. MAY SEE SOME IC/IF AROUND DAWN...BUT BELIEVE IT WILL
REMAIN VFR FOR NOW. GUSTY NORTHWEST WINDS SHOULD DIMINSIH LATE
TONIGHT AND INCREASE INTO MONDAY BEFORE RELAXING BY MONDAY
EVENING. REMAINING VFR INTO MONDAY NIGHT.
/OUTLOOK FOR KMSP/
MON NIGHT...VFR. NW WINDS 5-10 KT.
TUE...VFR. W WINDS 5-10 KT.
WED...VFR. WINDS NEAR CALM.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WIND CHILL WARNING UNTIL NOON CST TUESDAY FOR MNZ041>045-047>070-
073>078-082>085-091>093.
WI...WIND CHILL WARNING UNTIL NOON CST TUESDAY FOR WIZ014>016-023>028.
&&
$$
SHORT TERM...RAH
LONG TERM...JLT
AVIATION...DWE
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
348 AM CST SAT JAN 4 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM CST SAT JAN 4 2014
WE ARE SEEING THE FIRST SIGNS OF THE COLD OUTBREAK SET TO ARRIVE
THIS WEEKEND...WITH TEMPERATURES ACROSS WEST CENTRAL MINNESOTA
HAVING PLUMMETED FROM THE MID 30S/LOWER 40S TO THE SINGLE DIGITS
WITHIN THE LAST 9 HOURS...COMPLIMENTS OF NORTHWEST WINDS AT 25 TO 35
MPH /GUSTING TO AROUND 45 MPH/. THE WINTRY MIX OF PRECIPITATION THAT
WAS ENDURED ACROSS MUCH OF CENTRAL AND SOUTHWEST MN FRIDAY EVENING
DID A NUMBER ON ROAD CONDITIONS...PER THE MNDOT 511 MAP.
ADDITIONALLY...NORTHWEST WINDS WILL CONTINUE TO YIELD AREAS OF
BLOWING SNOW IN THOSE SAME AREAS THIS MORNING. WILL THEREFORE EXTEND
THE WINTER WEATHER ADVISORY ACROSS THE WEST FOR A FEW HOURS PAST
DAYBREAK...WHERE THE EFFECTS OF BLOWING SNOW WILL LIKELY BE
GREATER THIS MORNING.
TEMPERATURES WILL CONTINUE TO FALL THROUGHOUT THE DAY...WITH BELOW
ZERO READINGS LIKELY ACROSS MUCH OF WESTERN MN BY MID
AFTERNOON...AND NEARLY THE ENTIRE FORECAST AREA BY 00Z. WIND CHILL
READINGS WILL LOITER AROUND -25 TODAY...BUT WILL FOCUS ON
HIGHLIGHTING THE ARRIVAL OF THE MORE DANGEROUS SURGE OF COLD AIR
THIS EVENING/TONIGHT...KEEPING THE START TIME OF THE WIND CHILL
WARNING AT 00Z SUNDAY. WIND CHILL READINGS WILL DIP TO BETWEEN 35
AND 45 BELOW BY DAYBREAK SUNDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 348 AM CST SAT JAN 4 2014
THE INCREDIBLE...HISTORIC COLD OUTBREAK IS STILL ON TRACK FOR THE
FIRST HALF OF THE LONG TERM PERIOD WITH VERY HIGH CONFIDENCE ALL
AROUND. GUIDANCE IS SLIGHTLY COLDER THAN YESTERDAY...BUT STILL IN
THE GENERAL BALLPARK OF WHAT WE HAVE BEEN CALLING FOR. NAM/GEM ARE
THE COLDEST SOLUTIONS ALOFT WHILE GFS/ECMWF ARE COLDEST AT THE
SURFACE SUNDAY AND MONDAY. THE COLDEST 850 MB TEMP RECORDED AT
MPX/STC WAS -39.3C ON 1/10/1982. THE 06Z NAM AND 00Z GEM BRING THE
-37C/-36C CONTOUR ACROSS THE MSP METRO SUNDAY NIGHT WHILE
GFS/ECMWF ARE MORE IN THE -32 TO -34C RANGE. REGARDLESS...CERTAINLY
SOME RARE AIR. THEREFORE...NOT OVERLY CONCERNED ABOUT OUR CHANCES
TO APPROACH OR EXCEED RECORDS...CLOUD COVER PRESENT OR
NOT...AND STRONG WINDS PRESENT OR NOT.
THE FIRST LOBE OF BITTER COLD AIR WILL ALREADY BE IN PLACE AT THE
START OF THE PERIOD...WITH A SECONDARY COLD FRONT SINKING SOUTH
SUNDAY AFTERNOON. AS IF TEMPS WEREN/T TOO COLD ENOUGH THEY WILL
LIKELY CONTINUE TO FALL SUNDAY AFTERNOON AND LEAD TO THE COLDEST
PERIOD IN ALMOST TWO DECADES SUNDAY NIGHT. HIGHS WILL BE IN THE
LOW TO MID TEENS BELOW ZERO EARLY AFTERNOON BEFORE FALLING TO 20
TO 25 BELOW EARLY EVENING. AS THE MOST INTENSE CHUNK OF AIR
ROTATES THROUGH LATE SUNDAY NIGHT...TEMPS SHOULD BE ABLE TO FALL
ANOTHER 10 DEGREES OR SO IN MOST LOCATIONS AND BOTTOM OUT BETWEEN
25 AND 35 BELOW EARLY MONDAY MORNING. STRONG WEST WINDS BETWEEN 15
AND 20 MPH /GUSTS TO 30 MPH/ WILL DRIVE WIND CHILLS DOWN INTO THE
55 TO 65 BELOW RANGE. SLOW MODERATION WILL OCCUR MONDAY...BUT
HIGHS WILL STRUGGLE TO GET MUCH WARMER THAN 20 BELOW WITH DAYTIME
WIND CHILLS HOVERING BETWEEN 45 AND 55 BELOW. STRONG WAA ALOFT
WILL PREVENT TEMPS FROM PLUMMETING TOO MUCH MONDAY NIGHT. BY
TUESDAY...TEMPS WILL RECOVER TO A MORE ACCEPTABLE COLD OUTBREAK
LEVEL. DID NOT CHANGE TOO MUCH ON THIS SHIFT...ALTHOUGH DID LOWER
TEMPS A TICK OR TWO IN SPOTS SUNDAY THROUGH MONDAY PER LATEST
GUIDANCE TRENDS.
MODELS DIFFER A BIT ON HOW QUICKLY TO PUSH THE ARCTIC AIR OUT.
GEM IS THE MOST AGGRESSIVE WITH -20S FOR LOWS THROUGH WEDNESDAY
NIGHT. THIS MAY VERY WELL OCCUR IN THE LIGHT WIND REGIME UNDER
HIGH PRESSURE. FEEL THE GFS AND ECMWF ARE TOO WARM IN THIS
SCENARIO AND HAVE TRENDED DOWNWARD A BIT FROM THE PREVIOUS
FORECAST.
STRONGER SOUTHERLY FLOW WILL ESTABLISH ITSELF LATE NEXT WEEK WITH
MUCH MILDER CONDITIONS RETURNING. HIGHS IN THE 30S AND POSSIBLY
LOW 40S APPEAR IN THE OFFING NEXT WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1119 PM CST FRI JAN 3 2014
BAND OF PCPN CURRENTLY MOVING THROUGH ALONG/AHEAD OF FRONTAL
BOUNDARY. PCPN-TYPE IS A MIXED BAG GIVEN ABOVE FREEZING AIR
ALOFT... WITH SLEET... FREEZING RAIN... AND SNOW OCCURRING. THE
GENERAL TREND WILL BE FOR THINGS TO TRANSITION TO LIGHT SNOW AND
END WITHIN THE NEXT FEW HOURS FROM WEST TO EAST. WINDS WILL BE
SHIFTING TO THE WEST AND NORTHWEST... AND WE/LL HAVE SOME MVFR
CEILINGS AROUND INTO SATURDAY MORNING. THERE REMAINS SOME QUESTION
AS TO HOW QUICKLY WE/LL LOSE THE LOW CEILINGS AS THE ARCTIC AIR
STARTS TO MOVE IN... WITH THE NAM AND RAP SUGGESTING QUITE A BIT
MORE BOUNDARY LAYER RH IN COMPARISON TO THE GFS. WILL REMAIN
OPTIMISTIC GIVEN THE OVERALL ABSOLUTE DRYNESS OF THE AIRMASS...
AND ALLOW FOR THINGS TO SCATTER OUT ON SATURDAY. ALSO REMOVED
QUITE A BIT OF THE BLOWING SNOW... SINCE MUCH OF IT WAS COVERED UP
BY SLEET AND FREEZING RAIN AND SHOULD BE TOUGHER TO BLOW AROUND.
HOWEVER... THAT IS CERTAINLY SOMETHING WHICH COULD STILL BE AN
ISSUE IF THE ASSUMPTION THERE IS NOTHING TO BLOW AROUND IS
INCORRECT.
KMSP...PRIMARY UNCERTAINTIES ARE WILL CEILINGS THROUGH SATURDAY
MORNING AND WHETHER WE/LL SEE MUCH BELOW 017 FT AGL... AND ALSO
IF/WHEN THINGS WILL SCATTER OUT. THE MIXED PCPN ONGOING SHOULD BE
ENDING WITHING A FEW HOURS.
/OUTLOOK FOR KMSP/
SATURDAY OVERNIGHT...VFR. NORTHWEST WIND 10 TO 15 KT.
SUNDAY...MVFR CEILINGS POSSIBLE LATE. NORTHWEST WIND 10 TO 20 KT.
SUNDAY NIGHT...MVFR CEILINGS EXPECTED. NORTHWEST WIND 10 TO 15 KT.
MONDAY...MVFR CEILINGS EXPECTED EARLY. NORTHWEST WIND 10 TO 20 KT.
MONDAY NIGHT...VFR. WEST WIND 5 TO 15 KT.
TUESDAY...VFR. WEST WIND 5 TO 10 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
MNZ043>045-050>053-059>063-066>070-075>078-083>085-092-093.
WIND CHILL WARNING FROM 6 PM THIS EVENING TO NOON CST TUESDAY
FOR MNZ041>045-047>070-073>078-082>085-091>093.
WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR MNZ041-
042-047>049-054>058-064-065-073-074-082-091.
WI...WINTER WEATHER ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
WIZ014>016-023>028.
WIND CHILL WARNING FROM 6 PM THIS EVENING TO NOON CST TUESDAY
FOR WIZ014>016-023>028.
&&
$$
SHORT TERM...LS
LONG TERM...BORGHOFF
AVIATION...
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1126 PM CST FRI JAN 3 2014
.UPDATE...
ISSUED AT 1119 PM CST FRI JAN 3 2014
UPDATED TO INCLUDE 06Z AVIATION DISCUSSION BELOW.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 328 PM CST FRI JAN 3 2014
BEFORE THE MAIN SURGE OF EXTREMELY COLD AIR ARRIVES OVER THE
WEEKEND...A STRONG STORM SYSTEM AHEAD OF THIS AIR MASS HAS MODIFIED
ENOUGH TO PRODUCE A PERIOD OF FREEZING RAIN AND SLEET THIS EVENING
AS IT MOVES FROM THE WESTERN DAKOTAS...EASTWARD ACROSS THE UPPER
MIDWEST OVERNIGHT. REGIONAL RADAR ALSO ALREADY INDICATED A LARGE
AREA OF PRECIPITATION DEVELOPING ACROSS CENTRAL ND...SOUTHWARD INTO
CENTRAL SD. ABV THE SFC...TEMPS HAVE WARMED SIGNIFICANTLY...WITH 85H
TEMPS NEAR +6C IN WC MN TO NEAR 0C IN EC MN. HOWEVER...IN THE LOWEST
1-2K...TEMPS WERE NEAR -10C IN EC MN...TO -4C IN WC MN. THE DEPTH OF
THE COLDER TEMPS IN EASTERN MN WILL ALLOW FOR MAINLY SLEET AND SOME
-SN. HOWEVER...FURTHER TO THE WEST...THE PRECIPITATION HAS A BETTER
CHC OF HOLDING AS LIQUID AND NOT REFREEZING IN THE FORM OF SLEET.
THEREFORE...A BETTER CHC OF FREEZING RAIN IS EXPECTED IN WC MN
DURING THE EVENING HRS BEFORE THE ARCTIC FRONT ARRIVES AFT MIDNIGHT.
DEPENDING UPON HOW MUCH FURTHER THE WARMER AIR ADVECTS TO THE
EAST...WILL DEPEND IF EASTERN MN GETS MORE FREEZING RAIN OR SLEET.
WC WI WILL LIKELY REMAIN SNOW OR A MIXTURE OF SLEET AND SNOW. QPF
AMTS REMAIN FAIRLY LIGHT...BUT EVEN A FEW HUNDREDTHS OF AN INCH OF
FREEZING RAIN CAN CAUSE HAZARDOUS ROADS IF NOT TREATED. A WINTER WX
ADV WAS ISSUED BASED ON THE FREEZING PRECIPITATION AND THEN BLOWING
AND DRIFTING SNOW AFTER MIDNIGHT. ONLY SMALL CHGS IN THE FORECAST ON
SATURDAY AS TEMPS WILL CONTINUE TO FALL THROUGHOUT THE DAY. WIND
CHILL VALUES BY LATE SATURDAY AFTERNOON WILL RANGE FROM -30 TO -35F
IN CENTRAL/WC MN...TO AROUND -15 IN WC WI.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 328 PM CST FRI JAN 3 2014
THE WORST ARCTIC OUTBREAK SO FAR THIS COLD SEASON WILL BE UNDERWAY
AT THE START OF THE LONG TERM. DETERMINISTIC SOLUTIONS CONTINUE TO
DRIVE A POLAR VORTEX... CURRENTLY OVER THE YUKON... TO NEAR KDLH BY
SUNDAY EVENING... WITH 1000-500MB THICKNESS VALUES BELOW 486
(DAM). VERTICAL PROFILES BETWEEN THE SURFACE AND 850MB SHOW
TEMPERATURES IN THE -30 TO -35 DEG C RANGE ACROSS THE CWA SUNDAY
NIGHT AND MONDAY. THIS UPCOMING COLD IS QUITE SIMILAR PATTERN-WISE TO
THAT IN EARLY JANUARY 1982. A CHECK ON WEATHER MAPS DURING THAT
COLD OUTBREAK SHOWED THE UPPER LOW BOTTOMING OUT ACROSS THE UPPER
GREAT LAKES ALONG WITH THE SURFACE HIGH STAYING WELL WEST AND
SOUTH OF THE FA. THIS RESULTS IN THE LIKELYHOOD OF SOME CLOUDINESS
DUE TO PROXIMITY OF THE UPPER LOW AND ALSO A NW WIND FROM 10 TO
20 MPH IN THE HEART OF THE ARCTIC COLD. MSP DURING THE COLD WAVE
IN EARLY JANUARY 1982 HAD A LOW TEMPERATURES OF -26 DEG F. IN
FACT...LOWS ACROSS THE ENTIRE FA REACHED -25 TO -32 DEG F. THIS IS
VERY SIMILAR THE FORECAST VALUES AHEAD.
TODAY/S FORECAST HAS LOWS DROPPING BELOW ZERO SATURDAY EVENING AND
NOT RISING ABOVE ZERO UNTIL WEDNESDAY. THIS IS A RUN OF 88 HOURS
BELOW ZERO FOR MSP. NOT A TOP 10 RECORD... WHICH RUNS FROM 186
HOURS DOWN TO 130 HOURS. THE WORST STRETCH OF COLD IS FROM SUNDAY
NIGHT THROUGH TUESDAY. LOWS SUNDAY NIGHT ARE FORECAST IN THE -25
TO -32 DEG F RANGE... WITH -27 FOR MSP (THIS WOULD TIE THE RECORD).
THIS WOULD ALSO BE THE COLDEST MSP HAS BEEN SINCE DECEMBER 26TH
1996. THE ECE AND GFS MOS FOR MSP ARE -27 AND -29 DEG F
RESPECTIVELY. THEN HAVE THE POTENTIAL FOR RECORD LOW HIGHS ON
MONDAY WITH VALUES ONLY FORECAST IN THE -14 TO -20 DEG F RANGE. WE
HAVE MSP AT -17 FOR THE HIGH ON MONDAY WHICH WOULD BE A RECORD LOW
HIGH (-14). MONDAY NIGHT WE ARE BACK DOWN IN THE -20 TO -26 DEG F
RANGE WITH HIGHS ON TUESDAY IN THE SINGLE DIGITS BELOW ZERO.
AS MENTIONED EARLIER...NW WINDS WILL BE BLOWING THE WHOLE TIME.
WIND CHILL VALUES SUNDAY NIGHT AND MONDAY WILL BE IN THE -50 TO
-60 DEG F RANGE WITH VALUES MONDAY NIGHT AND TUESDAY MORNING IN
THE -40 TO -50 DEG F RANGE. A WIND CHILL WARNING REMAINS IN EFFECT
FROM 6 PM SATURDAY UNTIL NOON ON TUESDAY.
THE BALANCE OF THE WORKWEEK WILL BE ONE OF TEMPERATURE MODERATION
AS THE FLOW BECOMES MORE WESTERLY. HIGHS INCREASE FROM THE SINGLE
DIGITS ABOVE ZERO ON WEDNESDAY TO THE UPPER 20S BY FRIDAY. THERE
IS SOME DISAGREEMENT BETWEEN THE GFS/GEM AND EC ON HOW CLOSE WE
WILL BE TO A SOUTHERN STREAM SNOW EVENT. THE GEM AND GFS WOULD
JUST NICK OUR EASTERN AND SOUTHERN AREAS WHILE THE EC WOULD BRING
THE SNOW THROUGH A NORTHERN STREAM FEATURE. COLLABORATION TODAY
WAS TO KEEP VERY SMALL POPS CONFINED TO AREAS EAST AND SOUTH OF
THE TWIN CITIES FOR WEDNESDAY/WEDNESDAY NIGHT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1119 PM CST FRI JAN 3 2014
BAND OF PCPN CURRENTLY MOVING THROUGH ALONG/AHEAD OF FRONTAL
BOUNDARY. PCPN-TYPE IS A MIXED BAG GIVEN ABOVE FREEZING AIR
ALOFT... WITH SLEET... FREEZING RAIN... AND SNOW OCCURRING. THE
GENERAL TREND WILL BE FOR THINGS TO TRANSITION TO LIGHT SNOW AND
END WITHIN THE NEXT FEW HOURS FROM WEST TO EAST. WINDS WILL BE
SHIFTING TO THE WEST AND NORTHWEST... AND WE/LL HAVE SOME MVFR
CEILINGS AROUND INTO SATURDAY MORNING. THERE REMAINS SOME QUESTION
AS TO HOW QUICKLY WE/LL LOSE THE LOW CEILINGS AS THE ARCTIC AIR
STARTS TO MOVE IN... WITH THE NAM AND RAP SUGGESTING QUITE A BIT
MORE BOUNDARY LAYER RH IN COMPARISON TO THE GFS. WILL REMAIN
OPTIMISTIC GIVEN THE OVERALL ABSOLUTE DRYNESS OF THE AIRMASS...
AND ALLOW FOR THINGS TO SCATTER OUT ON SATURDAY. ALSO REMOVED
QUITE A BIT OF THE BLOWING SNOW... SINCE MUCH OF IT WAS COVERED UP
BY SLEET AND FREEZING RAIN AND SHOULD BE TOUGHER TO BLOW AROUND.
HOWEVER... THAT IS CERTAINLY SOMETHING WHICH COULD STILL BE AN
ISSUE IF THE ASSUMPTION THERE IS NOTHING TO BLOW AROUND IS
INCORRECT.
KMSP...PRIMARY UNCERTAINTIES ARE WILL CEILINGS THROUGH SATURDAY
MORNING AND WHETHER WE/LL SEE MUCH BELOW 017 FT AGL... AND ALSO
IF/WHEN THINGS WILL SCATTER OUT. THE MIXED PCPN ONGOING SHOULD BE
ENDING WITHING A FEW HOURS.
/OUTLOOK FOR KMSP/
SATURDAY OVERNIGHT...VFR. NORTHWEST WIND 10 TO 15 KT.
SUNDAY...MVFR CEILINGS POSSIBLE LATE. NORTHWEST WIND 10 TO 20 KT.
SUNDAY NIGHT...MVFR CEILINGS EXPECTED. NORTHWEST WIND 10 TO 15 KT.
MONDAY...MVFR CEILINGS EXPECTED EARLY. NORTHWEST WIND 10 TO 20 KT.
MONDAY NIGHT...VFR. WEST WIND 5 TO 15 KT.
TUESDAY...VFR. WEST WIND 5 TO 10 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL 3 AM CST SATURDAY FOR MNZ041>045-
047>070-073>078-082>085-091>093.
WIND CHILL WARNING FROM 6 PM SATURDAY TO NOON CST TUESDAY FOR
MNZ041>045-047>070-073>078-082>085-091>093.
WI...WINTER WEATHER ADVISORY UNTIL 3 AM CST SATURDAY FOR WIZ014>016-
023>028.
WIND CHILL WARNING FROM 6 PM SATURDAY TO NOON CST TUESDAY FOR
WIZ014>016-023>028.
&&
$$
UPDATE...
SHORT TERM...JLT
LONG TERM...RAH
AVIATION...
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1156 AM CST Sat Jan 4 2014
.UPDATE...
Issued at 1148 AM CST SAT JAN 4 2014
Based on a northern band of snow developing across northern MO this
afternoon have added one more row of counties to the northern portion
of the winter Weather Advisory. Have also broken off the far southern
counties with a later start time for snow.
UPDATE Issued at 1030 AM CST SAT JAN 4 2014
Have delayed the southward development of snow into the CWA. Current
band of light snow from southeast NE across southern IA tied to the
passing of the northern shortwave with elevated frontogenesis. 12z
NAM and RAP keep QPF north of Highway 36 through 21z and based on
current radar trends and expectations seems reasonable to delay snow
development for most of the CWA. 12z NAM has also jumped onto the
previous runs of the GFS in developing two separate bands of
snow...one across northern MO associated with the elevated
frontogenesis and a second and likely heavier band tied to the chunk
of energy and speed max diving southeast into the Central Rockies.
This energy is expected to spread into KS/OK this evening with a
significant PV anomaly digging into the base of the deepening upper
trough.
Have also increased snow amounts across northern MO due to this first
band which is expected to from by mid afternoon. Have also kept
categorical PoPs longer over the southeastern CWA through the night.
Could see some light rain across the far southern counties this
afternoon with temperatures well above freezing. Shouldn`t be much
nor last long as the cold front will push through by early evening.
&&
.SHORT TERM...(Today through Sunday Afternoon)
Issued at 335 AM CST SAT JAN 4 2014
In the short term, the main focus will be snow chances and amounts
for this afternoon through Sunday morning as a wintry system pushes
across the region. Two separate systems will result in snow chances
around the forecast area; 1) a southeastward moving cold front that
is currently located from central NE through north central IA, and
2) a shortwave trough lifting northeastward out of the southern
Plains. The primary snow-producer for our area will be the former,
especially along the elevated ~700 mb front.
Very light, patchy snow showers have developed behind the surface
cold front in portions of eastern NE and northern IA early this
morning, and will transition southward as the day progresses. As the
front moves south, it will encounter better moisture especially
below ~600-650 mb, helping light snow to fill in and increase in
intensity. Precipitation amounts will increase from northwest to
southeast where the better moisture resides, but still may not be
overly impressive with most of the lift/forcing centered along and
above the 700 mb front, through an increasingly dry layer. However,
quickly falling temperatures will help saturated portions of the
sounding to fall to around or below the -10 C mark, increasing snow
to liquid ratios to around 15:1 or greater by this evening into the
overnight hours. The greatest snow accumulations are expected from
00z to 09z Sunday, but light snow could stretch from mid afternoon
through mid-morning Sunday. Total amounts will range from less than
an inch in far northwest MO, to around 2 inches in the KC metro, to
4 inches or greater in our far southeast. Have issued a winter
weather advisory for areas along and southeast of a line from
Leavenworth county KS to Adair county MO, generally for 2-4 inches
of snow. Some enhancement of snow totals may occur in the far
southeast where the second (southern) system may brush our CWA this
evening ahead of the elevated cold front, possibly allowing for some
4-5 inch totals along our southeastern border.
Temperatures today may not rise much this morning under increasing
clouds, but won`t need to go far to make it into the middle to upper
30s across much of the region. The surface front will push into
northwest MO by late morning and should clear the forecast area by 6
PM, with falling temperatures trailing not far behind. Very minimal
clearing is expected tonight except in far northwest MO, but cold
air advection should knock temperatures into the single digits or
lower teens for most of the CWA by early Sunday morning, and little
to no diurnal rise is expected for Sunday.
.LONG TERM...(Sunday Night through Friday)
Issued at 335 AM CST SAT JAN 4 2014
The primary concern for the mid and long range forecast periods will
be the arrival of the arctic airmass Sunday night into Monday
morning. H85 temperatures of -25C to -30C will overspread the
forecast area. Early morning low temperatures are expected to fall
to the -10F to -13F range north to around -6F south. In addition,
breezy northwesterly winds of 10 to 20 mph will result in
dangerously cold wind chill readings, with values between -25F to
-35F. A wind chill warning will likely be required for Sunday night
into midday Monday for the entire forecast area. Bitterly cold
temperatures will continue during the day on Monday, with highs only
reaching the -5F to 5F above zero range. One more dangerously cold
night is expected Monday night into Tuesday morning, with lows
between -10F to 0F. Wind speeds are expected to be lower compared to
the previous night, resulting in wind chill values slightly less
extreme than the previous night.
Temperatures will gradually moderate throughout the remainder of the
work week, with readings finally reaching near normal levels by
Friday. Westerly to southwesterly flow aloft will prevail during
this period, with several weak upper disturbances projected to move
near/across the area. A chance of light snow will be possible
Wednesday into Wednesday night, with a chance of light snow or light
rain possible Friday into Friday night. A good amount of uncertainty
exists with both scenarios with timing, intensity, and track of each
upper disturbance. Overall, current model solutions suggest that
notable amounts of precipitation are not expected with either
system.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1148 AM CST SAT JAN 4 2014
Based on latest short term models and supported by current radar
trends have slowed down the arrival of snow into the terminals. Have
also attempted to pick out a 4 hour wind with the best potential for
heavier snow, lower visibilities and ceilings. Prefer to keep
ceilings in the MVFR category.
Expect a band of snow to develop across northern MO this afternoon
and gradually shift/spread southward reaching the MO river around 00z
or shortly thereafter. A larger area of snow is forecast to form this
evening across west central and central MO and east central KS as an
upper level system moves out of CO into KS and OK. This area of snow
will be widespread and persist through the night with snow amounts
increasing from west to east.
Expect 1 to 2 inches at KSTJ and 2 to 3 inches at KMCI/KMKC.
Cold front will be moving through the KC terminals right at the start
of the forecast with northerly winds increasing and becoming gusty a
2-3 hours after frontal passage. Winds will remain strong through the
rest of the forecast with a gradual decrease Sunday morning.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY from 3 PM this afternoon to 9 AM CST
Sunday FOR KSZ025-103>105.
WINTER WEATHER ADVISORY from 6 PM this evening to 9 AM CST
Sunday FOR KSZ057-060.
MO...WINTER WEATHER ADVISORY from 3 PM this afternoon to 9 AM CST
Sunday FOR MOZ013>017-020>025-028>033-037>040.
WINTER WEATHER ADVISORY from 6 PM this evening to 9 AM CST
Sunday FOR MOZ043>046-053-054.
&&
$$
UPDATE...MJ
SHORT TERM...Laflin
LONG TERM...Blair
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1044 AM CST Sat Jan 4 2014
.UPDATE...
Issued at 1030 AM CST SAT JAN 4 2014
Have delayed the southward development of snow into the CWA. Current
band of light snow from southeast NE across southern IA tied to the
passing of the northern shortwave with elevated frontogenesis. 12z
NAM and RAP keep QPF north of Highway 36 through 21z and based on
current radar trends and expectations seems reasonable to delay snow
development for most of the CWA. 12z NAM has also jumped onto the
previous runs of the GFS in developing two separate bands of
snow...one across northern MO associated with the elevated
frontogenesis and a second and likely heavier band tied to the chunk
of energy and speed max diving southeast into the Central Rockies.
This energy is expected to spread into KS/OK this evening with a
significant PV anomaly digging into the base of the deepening upper
trough.
Have also increased snow amounts across northern MO due to this first
band which is expected to from by mid afternoon. Have also kept
categorical PoPs longer over the southeastern CWA through the night.
Could see some light rain across the far southern counties this
afternoon with temperatures well above freezing. Shouldn`t be much
nor last long as the cold front will push through by early evening.
&&
.SHORT TERM...(Today through Sunday Afternoon)
Issued at 335 AM CST SAT JAN 4 2014
In the short term, the main focus will be snow chances and amounts
for this afternoon through Sunday morning as a wintry system pushes
across the region. Two separate systems will result in snow chances
around the forecast area; 1) a southeastward moving cold front that
is currently located from central NE through north central IA, and
2) a shortwave trough lifting northeastward out of the southern
Plains. The primary snow-producer for our area will be the former,
especially along the elevated ~700 mb front.
Very light, patchy snow showers have developed behind the surface
cold front in portions of eastern NE and northern IA early this
morning, and will transition southward as the day progresses. As the
front moves south, it will encounter better moisture especially
below ~600-650 mb, helping light snow to fill in and increase in
intensity. Precipitation amounts will increase from northwest to
southeast where the better moisture resides, but still may not be
overly impressive with most of the lift/forcing centered along and
above the 700 mb front, through an increasingly dry layer. However,
quickly falling temperatures will help saturated portions of the
sounding to fall to around or below the -10 C mark, increasing snow
to liquid ratios to around 15:1 or greater by this evening into the
overnight hours. The greatest snow accumulations are expected from
00z to 09z Sunday, but light snow could stretch from mid afternoon
through mid-morning Sunday. Total amounts will range from less than
an inch in far northwest MO, to around 2 inches in the KC metro, to
4 inches or greater in our far southeast. Have issued a winter
weather advisory for areas along and southeast of a line from
Leavenworth county KS to Adair county MO, generally for 2-4 inches
of snow. Some enhancement of snow totals may occur in the far
southeast where the second (southern) system may brush our CWA this
evening ahead of the elevated cold front, possibly allowing for some
4-5 inch totals along our southeastern border.
Temperatures today may not rise much this morning under increasing
clouds, but won`t need to go far to make it into the middle to upper
30s across much of the region. The surface front will push into
northwest MO by late morning and should clear the forecast area by 6
PM, with falling temperatures trailing not far behind. Very minimal
clearing is expected tonight except in far northwest MO, but cold
air advection should knock temperatures into the single digits or
lower teens for most of the CWA by early Sunday morning, and little
to no diurnal rise is expected for Sunday.
.LONG TERM...(Sunday Night through Friday)
Issued at 335 AM CST SAT JAN 4 2014
The primary concern for the mid and long range forecast periods will
be the arrival of the arctic airmass Sunday night into Monday
morning. H85 temperatures of -25C to -30C will overspread the
forecast area. Early morning low temperatures are expected to fall
to the -10F to -13F range north to around -6F south. In addition,
breezy northwesterly winds of 10 to 20 mph will result in
dangerously cold wind chill readings, with values between -25F to
-35F. A wind chill warning will likely be required for Sunday night
into midday Monday for the entire forecast area. Bitterly cold
temperatures will continue during the day on Monday, with highs only
reaching the -5F to 5F above zero range. One more dangerously cold
night is expected Monday night into Tuesday morning, with lows
between -10F to 0F. Wind speeds are expected to be lower compared to
the previous night, resulting in wind chill values slightly less
extreme than the previous night.
Temperatures will gradually moderate throughout the remainder of the
work week, with readings finally reaching near normal levels by
Friday. Westerly to southwesterly flow aloft will prevail during
this period, with several weak upper disturbances projected to move
near/across the area. A chance of light snow will be possible
Wednesday into Wednesday night, with a chance of light snow or light
rain possible Friday into Friday night. A good amount of uncertainty
exists with both scenarios with timing, intensity, and track of each
upper disturbance. Overall, current model solutions suggest that
notable amounts of precipitation are not expected with either
system.
&&
.AVIATION...(For the 12Z TAFS through 12Z Sunday Morning)
Issued at 537 AM CST SAT JAN 4 2014
VFR conditions and mainly light southwest winds will be replaced by
MVFR to possibly IFR stratus and breezy north winds during the early
to mid afternoon hours behind a southeastward moving cold front. In
addition, light to moderate snow will develop during the afternoon
and will spread southeast across the area during the late afternoon
and evening hours. Reduced visibilities and slightly lower ceilings
are possible while snow is falling. Snow will taper off from
northwest to southeast tonight into Sunday morning, ending between
09z and 15z.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY from 3 PM this afternoon to 9 AM CST
Sunday FOR KSZ057-060-103>105.
MO...WINTER WEATHER ADVISORY from 3 PM this afternoon to 9 AM CST
Sunday FOR MOZ017-021>025-028>033-037>040-043>046-053-054.
&&
$$
UPDATE...MJ
SHORT TERM...Laflin
LONG TERM...Blair
AVIATION...Laflin
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
238 AM CST SAT JAN 4 2014
.SYNOPSIS...
ISSUED AT 237 AM CST SAT JAN 4 2014
THE ARCTIC FRONT AS OF 08Z HAD MOVED THROUGH MITCHELL
SD...VALENTINE AND SCOTTSBLUFF NE. A 1-2 HOUR SURGE IN WIND SPEEDS
BEHIND THE FRONT RESULTING IN GUSTS UP TO 35 KTS. TEMPERATURES IN
NEBRASKA RANGE FROM 27 AT VTN TO 40 AT ALBION. EARLIER RADAR
RETURNS HAVE MOSTLY DISAPPEARED IN WESTERN NEBR. LOOKING FOR
TEMPERATURES IN CENTRAL AND SWRN NEBR TO WARM TO AROUND 40
DEGREES IN THE NEXT FEW HOURS BEFORE COOLING BACK INTO THE UPPER
20S TOWARD 12Z.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 237 AM CST SAT JAN 4 2014
MUCH COLDER AIR WILL SWEEP INTO WESTERN NEBRASKA TODAY BEHIND THE ARCTIC
FRONT. EARLY MORNING HIGHS ALL AREAS. TEMPERATURES TO FALL INTO
THE MID TEENS ACROSS THE NCTRL BY LATE AFTERNOON. THERE IS A SLIGHT
CHANCE FOR SNOW ACROSS FAR SWRN AREAS TODAY WHICH WILL BE ON THE
NORTHERN PERIPHERY OF SUPPORTED SNOW AREA ACROSS COLORADO INTO WRN
AND CNTRL KANSAS.
FOR TONIGHT...LOW CHC POPS NEAR 30 PERCENT MAINLY WEST OF HWY 83
WITH A SLIGHT CHANCE INTO EASTERN ZONES AFTER MIDNIGHT. BEST AREA
OF FRONTOGENESIS ACROSS NRN WYOMING INTO SWRN SD WILL WEAK AND
TRANSLATE SOUTHEASTWARD INTO WESTERN NEBRASKA OVERNIGHT. WHILE MOST
AREA MAY ONLY SEE A DUSTING...WILL NEED TO MONITOR MODEL TRENDS
AS THE NAM SHOWING SNOW AMOUNTS AROUND 1 INCH IN THE EASTERN
PANHANDLE. WHILE VERY COLD TEMPERATURES WILL OCCUR OVERNIGHT FROM
NEAR ZERO NCTRL TO THE UPPER SINGLE DIGITS FAR SOUTHWEST. LOWEST
WIND CHILLS TO FALL TO NEAR 15 BELOW...WHICH SHOULD REMAIN BELOW
WIND CHILL ADVISORY LEVELS. THE MUCH COLDER AIR WILL ADVANCE
THROUGH CENTRAL SOUTH DAKOTA BY 12Z SUNDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 237 AM CST SAT JAN 4 2014
LOW PRESSURE DEVELOPING ON THE HIGH PLAINS WILL MOVE INTO SOUTHWEST
NEBRASKA AND THEN SOUTH INTO WESTERN KANSAS SUNDAY. THIS WILL GIVE A
BRIEF PERIOD IN WHICH SNOW SHOWERS COULD DEVELOP AS WARMER AIR LIFTS
UP OVER THE COLD BOUNDARY LAYER. FRONTOGENESIS IS ALSO LIKELY IN THE
270-285K LAYER AS THE SHORT WAVE TROUGH PIVOTS THROUGH THE AREA.
AS THE LOW SLIPS SOUTH...A REINFORCING SHOT OF ARCTIC AIR WILL POUR
INTO NEBRASKA. STILL...IT APPEARS THAT WESTERN NEBRASKA WILL BE ON
THE WESTERN EDGE OF THE COLDEST AIR WHILE THE COLDEST AIR SETTLES
INTO THE UPPER MIDWEST...THE EASTERN DAKOTAS AND MINNESOTA. IT
WILL CERTAINLY BE VERY COLD IN CENTRAL AND WESTERN NEBRASKA WITH
TEMPERATURES SUNDAY FROM AROUND ZERO IN VALENTINE AND ONEILL TO
THE LOWER TEENS IN THE EXTREME SOUTHWEST. LOWS SUNDAY NIGHT AND
EARLY MONDAY WILL BE BELOW ZERO OVER ALL OF NORTH CENTRAL TO
SOUTHWEST NEBRASKA WITH THE COLDEST AIR IN NORTH CENTRAL AND
NORTHWEST NEBRASKA. TEMPERATURES WILL BE SLIGHTLY HIGHER MONDAY
AND MONDAY NIGHT WITH A FAIRLY STRONG RECOVERY TO NEAR AVERAGE
TEMPERATURES TUESDAY THROUGH FRIDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1116 PM CST FRI JAN 3 2014
IT LOOKS LIKE MVFR SHOULD BECOME FAIRLY WIDESPREAD ONCE THE ARCTIC
FRONT CURRENTLY MOVING THROUGH WRN SD SWEEPS INTO THE FCST AREA
OVERNIGHT. THE RAP AND NAM MODELS HOLD THIS STRATUS IN PLACE
THROUGHOUT THE DAY SATURDAY WHILE THE GEM...GFS AND ECM MIX THESE
CLOUDS OUT. THE FORECAST SIDES WITH THE LATTER 3 MODELS FOR A MIX
OF MVFR AND VFR SATURDAY.
NOTE THAT LAPSE RATES WILL REMAIN QUITE STEEP SUPPORTING THE
DEVELOPMENT OF ISOLATED TO SCATTERED SNOW SHOWER COVERAGE
OVERNIGHT THROUGH SATURDAY EVENING WHICH COULD PRODUCE LOCAL IFR
CONDITIONS...MAINLY ALONG AND WEST OF HIGHWAY 61.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WIND CHILL WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY MORNING
FOR NEZ004>010-022>029-035>038-094.
&&
$$
SYNOPSIS...ROBERG
SHORT TERM...ROBERG
LONG TERM...SPRINGER
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1144 PM CST FRI JAN 3 2014
.SYNOPSIS...
ISSUED AT 313 PM CST FRI JAN 3 2014
H5 ANALYSIS THIS MORNING HAS A TANDEM OF LOW PRESSURES
OVER CANADA. THE FIRST OVER NORTHERN QUEBEC...AND A SECOND OVER
NORTHERN PORTIONS OF THE NORTHWEST TERRITORIES OF CANADA. RIDGING
HAS BUILT FROM THE GULF OF ALASKA INTO EASTERN ALASKA AND THE YUKON.
ACROSS THE WESTERN CONUS...A STRONG SHORTWAVE TROUGH WAS PRESENT
OVER THE PACIFIC NORTHWEST...WITH 150+ METER HT FALLS NOTED OVER
EASTERN WASHINGTON STATE...SERN BRITISH COLUMBIA INTO SWRN
SASKATCHEWAN. ACROSS THE SRN 2/3RDS OF THE CONUS...BROAD WEST
NORTHWESTERLY FLOW WAS PRESENT WITH PACIFIC AIR PUSHING INTO THE
CENTRAL AND SRN PLAINS THIS AFTERNOON. AT THE SURFACE...LOW PRESSURE
WAS PRESENT OVER NORTHWESTERN ND WITH A WARM FRONT EXTENDING SWD
INTO EASTERN NEBRASKA. A COLD FRONT EXTENDED TO THE WEST NORTHWEST
OF THIS FEATURE WITH MUCH COLDER AIR BEGINNING TO PUSH INTO NORTHERN
MT OVER THE PAST COUPLE OF HRS. AS OF 2 PM CST...UNDER PARTLY CLOUDY
SKIES...TEMPERATURES RANGED FROM 41 AT O`NEILL TO 63 AT IMPERIAL.
&&
.UPDATE...
ISSUED AT 1142 PM CST FRI JAN 3 2014
THE WINDS SWEEPING THROUGH SD LOOK PRETTY STRONG AND THE HRRR
SHOWS GUSTS TO 50 MPH AS THE FRONT SWINGS THROUGH PARTS OF
NORTHERN NEBRASKA TONIGHT. A WIND ADVISORY IS IN PLACE UNTIL 6 AM
CST FOR THIS FAST MOVING FRONT.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 313 PM CST FRI JAN 3 2014
COLD FRONT NUMBER ONE WILL ARRIVE TONIGHT BRINGING AN END TO THE
UNSEASONABLY WARM TEMPERATURES. THE FRONT WILL BEGIN TO IMPACT THE
AREA AFTER 00Z WITH SOME LIGHT RAIN/SNOW POSSIBLE ACROSS THE FAR NW
AS TEMPS INITIALLY NEAR FREEZING. TEMPS QUICKLY FALL BELOW ZERO AND
PRECIP TYPE BECOMES ALL SNOW. MOISTURE IS LIMITED WITH MODEL RH
GENERALLY LESS THAN 70 PERCENT FOR ANY GIVEN MID/UPPER LAYER. THE
NAM/RUC RETAIN THE BEST MOISTURE...GENERALLY IN THE BL...AND CLOUDS
INCREASED FOR STRATUS. LIFT IS MARGINALLY AND TOWARDS THE TOP OF THE
DENDRITIC GROWTH ZONE. SNOW CHANCES...ALBEIT SLIGHT AND WITH LOW
CONFIDENCE...CONTINUE ACROSS THE NW ZONES INTO THE EASTERN PANHANDLE
OVERNIGHT. LITTLE IF ANY ACCUMULATION EXPECTED. THE COLD AIR
ADVECTION WILL MAKE IT DIFFICULT TO WARM UP TOMORROW. ALSO EXPECT
SOME STRATUS TO SPREAD ACROSS THE AREA...THUS MORNING HIGHS ARE
LIKELY FOR MOST AREAS...WITH STEADY OF FALLING FOR THE AFTERNOON.
NORTH WINDS BEHIND THE FRONT WILL BE BREEZY AND WIND CHILLS FALL
INTO THE SINGLE DIGITS...AND SOME AREAS UP NORTH...SINGLE DIGITS
BELOW ZERO. UPPER LEVEL WAVE/SUPPORT TO SLIDE ACROSS KS...AND MAY
BRING SOME SN INTO FAR SW NEB...AROUND THE IMPERIAL TO HAYES CENTER
AREA...AGAIN LOW CONFIDENCE WITH BEST SUPPORT SOUTH OF THE CWA.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 312 PM CST FRI JAN 3 2014
SATURDAY NIGHT THROUGH MONDAY...MAIN FORECAST CHALLENGES
ARE TEMPERATURES...DANGEROUS WIND CHILLS AND LIGHT SNOW IN
ASSOCIATION WITH AN ARCTIC FRONT. FOR SATURDAY NIGHT PIECE ONE OF
THE ARCTIC AIR WILL PUSH SOUTHWEST INTO THE PANHANDLE AND WESTERN CWA
SATURDAY EVENING SETTING UP A BAROCLINIC ZONE ACROSS THE WESTERN HALF
OF THE CWA. ADDITIONAL SUPPORT FOR LIGHT SNOW WILL ARRIVE OVERNIGHT
AS THE LEFT FRONT QUAD OF THE JET LIFTS EAST ACROSS THE NORTHERN
ROCKIES. CROSS SECTIONS THROUGH THE EASTERN PANHANDLE AND WESTERN
CWA INDICATE DECENT MOISTURE BELOW 700MB WHICH IS COLLOCATED WITH
DECENT LIFT IN THE DENDRITIC ZONE SATURDAY EVENING. WITH MOISTURE
AND DYNAMICS IN PLACE...WILL CONTINUE TO MENTION CHANCES FOR LIGHT
SNOW SATURDAY NIGHT ROUGHLY WEST OF HIGHWAY 83. ON SUNDAY...THE MAIN
SHOT OF ARCTIC AIR WILL PUSH INTO THE FORECAST AREA SOMETIME DURING
THE LATE MORNING/EARLY AFTERNOON HOURS. AS THE ARCTIC AIR PUSHES
SOUTHWARD SUNDAY...STILL CANNOT RULE OUT SOME LIGHT SNOW IN
ASSOCIATION WITH THE ARCTIC FROPA AND WILL CONTINUE TO MENTION IT.
TEMPERATURES WILL BE TRICKY SUNDAY GIVEN THE TIMING OF THE
FRONT...AS HIGHS WILL OCCUR DURING THE MORNING IN THE NORTH AND
AROUND MIDDAY IN THE SOUTH. ON SUNDAY AFTERNOON STRONG COLD AIR
ADVECTION...WILL INCREASE NORTHERLY WINDS WHICH WILL COMBINE WITH
THE BITTERLY COLD AIR TO PRODUCE WIND CHILLS RANGING FROM 20 TO 40
BELOW ZERO SUNDAY EVENING. THESE READINGS MAY DIP TO BELOW 40 BELOW
IN THE NORTH BY 12Z MONDAY. DECIDED TO HOIST A WIND CHILL WATCH
ALONG AND NORTH OF HIGHWAY 92 FROM MIDDAY SUNDAY THROUGH MIDDAY
MONDAY...AS WIND CHILLS OF 30 TO 45 BELOW ZERO APPEAR POSSIBLE IN
THESE AREAS. COLD TEMPERATURES WILL CARRY OVER INTO MONDAY...HOWEVER
WINDS ARE EXPECTED TO BEGIN TO RELAX MONDAY AFTERNOON AS HIGH
PRESSURE BEGINS TO BUILD SOUTH INTO THE MISSOURI VALLEY.
TEMPERATURES MONDAY MORNING WILL RANGE FROM -15 IN THE NORTH TO
AROUND -3 IN FAR SWRN NEBRASKA. READINGS WILL REBOUND BACK TO THE
SINGLE DIGITS AND TEENS MONDAY AFTERNOON AS THE CORE OF THE ARCTIC AIR IS
SHOVED EAST INTO THE MISSISSIPPI VALLEY AND UPPER MIDWEST.
MONDAY NIGHT THROUGH FRIDAY...THE MID RANGE MODEL SOLUTIONS CONTINUE
TO HINT AT A PATTERN SHIFT NEXT WEEK...TO A MORE ZONAL PATTERN. THIS
WILL ALLOW WARMER PACIFIC AIR TO INFILTRATE THE WESTERN AND CENTRAL
CONUS...LEADING TO NORMAL TO ABOVE NORMAL TEMPERATURES NEXT WEEK.
THE ONE DAY WITH SLIGHTLY COOLER TEMPS WILL BE WEDNESDAY AS A
DISTURBANCE AND WEAK FRONTAL BOUNDARY PUSHES THROUGH THE NORTHERN
PLAINS. THIS WILL BE A GLANCING BLOW OF ARCTIC AIR...SO ITS IMPACTS
ON TEMPS WILL BE FAIRLY MINIMAL. H85 TEMPS WEDNESDAY THROUGH FRIDAY
WILL GENERALLY RANGE FROM ZERO TO 5C...SO HIGHS WILL GENERALLY BE IN
THE 30S WITH SOME 40S OVER SWRN NEBRASKA. DRY CONDS WILL CONTINUE IN
THE EXTENDED AS NO SIGNIFICANT CUTOFF SYSTEMS OR DISTURBANCES WILL
TRACK ACROSS THE CENTRAL PLAINS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1116 PM CST FRI JAN 3 2014
IT LOOKS LIKE MVFR SHOULD BECOME FAIRLY WIDESPREAD ONCE THE ARCTIC
FRONT CURRENTLY MOVING THROUGH WRN SD SWEEPS INTO THE FCST AREA
OVERNIGHT. THE RAP AND NAM MODELS HOLD THIS STRATUS IN PLACE
THROUGHOUT THE DAY SATURDAY WHILE THE GEM...GFS AND ECM MIX THESE
CLOUDS OUT. THE FORECAST SIDES WITH THE LATTER 3 MODELS FOR A MIX
OF MVFR AND VFR SATURDAY.
NOTE THAT LAPSE RATES WILL REMAIN QUITE STEEP SUPPORTING THE
DEVELOPMENT OF ISOLATED TO SCATTERED SNOW SHOWER COVERAGE
OVERNIGHT THROUGH SATURDAY EVENING WHICH COULD PRODUCE LOCAL IFR
CONDITIONS...MAINLY ALONG AND WEST OF HIGHWAY 61.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 6 AM CST /5 AM MST/ SATURDAY FOR NEZ004>010-
026>029-094.
WIND CHILL WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY MORNING
FOR NEZ004>010-022>029-035>038-094.
&&
$$
UPDATE...CDC
SYNOPSIS...CLB
SHORT TERM...MASEK
LONG TERM...CLB
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1117 PM CST FRI JAN 3 2014
.SYNOPSIS...
ISSUED AT 313 PM CST FRI JAN 3 2014
H5 ANALYSIS THIS MORNING HAS A TANDEM OF LOW PRESSURES
OVER CANADA. THE FIRST OVER NORTHERN QUEBEC...AND A SECOND OVER
NORTHERN PORTIONS OF THE NORTHWEST TERRITORIES OF CANADA. RIDGING
HAS BUILT FROM THE GULF OF ALASKA INTO EASTERN ALASKA AND THE YUKON.
ACROSS THE WESTERN CONUS...A STRONG SHORTWAVE TROUGH WAS PRESENT
OVER THE PACIFIC NORTHWEST...WITH 150+ METER HT FALLS NOTED OVER
EASTERN WASHINGTON STATE...SERN BRITISH COLUMBIA INTO SWRN
SASKATCHEWAN. ACROSS THE SRN 2/3RDS OF THE CONUS...BROAD WEST
NORTHWESTERLY FLOW WAS PRESENT WITH PACIFIC AIR PUSHING INTO THE
CENTRAL AND SRN PLAINS THIS AFTERNOON. AT THE SURFACE...LOW PRESSURE
WAS PRESENT OVER NORTHWESTERN ND WITH A WARM FRONT EXTENDING SWD
INTO EASTERN NEBRASKA. A COLD FRONT EXTENDED TO THE WEST NORTHWEST
OF THIS FEATURE WITH MUCH COLDER AIR BEGINNING TO PUSH INTO NORTHERN
MT OVER THE PAST COUPLE OF HRS. AS OF 2 PM CST...UNDER PARTLY CLOUDY
SKIES...TEMPERATURES RANGED FROM 41 AT O`NEILL TO 63 AT IMPERIAL.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 313 PM CST FRI JAN 3 2014
COLD FRONT NUMBER ONE WILL ARRIVE TONIGHT BRINGING AN END TO THE
UNSEASONABLY WARM TEMPERATURES. THE FRONT WILL BEGIN TO IMPACT THE
AREA AFTER 00Z WITH SOME LIGHT RAIN/SNOW POSSIBLE ACROSS THE FAR NW
AS TEMPS INITIALLY NEAR FREEZING. TEMPS QUICKLY FALL BELOW ZERO AND
PRECIP TYPE BECOMES ALL SNOW. MOISTURE IS LIMITED WITH MODEL RH
GENERALLY LESS THAN 70 PERCENT FOR ANY GIVEN MID/UPPER LAYER. THE
NAM/RUC RETAIN THE BEST MOISTURE...GENERALLY IN THE BL...AND CLOUDS
INCREASED FOR STRATUS. LIFT IS MARGINALLY AND TOWARDS THE TOP OF THE
DENDRITIC GROWTH ZONE. SNOW CHANCES...ALBEIT SLIGHT AND WITH LOW
CONFIDENCE...CONTINUE ACROSS THE NW ZONES INTO THE EASTERN PANHANDLE
OVERNIGHT. LITTLE IF ANY ACCUMULATION EXPECTED. THE COLD AIR
ADVECTION WILL MAKE IT DIFFICULT TO WARM UP TOMORROW. ALSO EXPECT
SOME STRATUS TO SPREAD ACROSS THE AREA...THUS MORNING HIGHS ARE
LIKELY FOR MOST AREAS...WITH STEADY OF FALLING FOR THE AFTERNOON.
NORTH WINDS BEHIND THE FRONT WILL BE BREEZY AND WIND CHILLS FALL
INTO THE SINGLE DIGITS...AND SOME AREAS UP NORTH...SINGLE DIGITS
BELOW ZERO. UPPER LEVEL WAVE/SUPPORT TO SLIDE ACROSS KS...AND MAY
BRING SOME SN INTO FAR SW NEB...AROUND THE IMPERIAL TO HAYES CENTER
AREA...AGAIN LOW CONFIDENCE WITH BEST SUPPORT SOUTH OF THE CWA.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 312 PM CST FRI JAN 3 2014
SATURDAY NIGHT THROUGH MONDAY...MAIN FORECAST CHALLENGES
ARE TEMPERATURES...DANGEROUS WIND CHILLS AND LIGHT SNOW IN
ASSOCIATION WITH AN ARCTIC FRONT. FOR SATURDAY NIGHT PIECE ONE OF
THE ARCTIC AIR WILL PUSH SOUTHWEST INTO THE PANHANDLE AND WESTERN CWA
SATURDAY EVENING SETTING UP A BAROCLINIC ZONE ACROSS THE WESTERN HALF
OF THE CWA. ADDITIONAL SUPPORT FOR LIGHT SNOW WILL ARRIVE OVERNIGHT
AS THE LEFT FRONT QUAD OF THE JET LIFTS EAST ACROSS THE NORTHERN
ROCKIES. CROSS SECTIONS THROUGH THE EASTERN PANHANDLE AND WESTERN
CWA INDICATE DECENT MOISTURE BELOW 700MB WHICH IS COLLOCATED WITH
DECENT LIFT IN THE DENDRITIC ZONE SATURDAY EVENING. WITH MOISTURE
AND DYNAMICS IN PLACE...WILL CONTINUE TO MENTION CHANCES FOR LIGHT
SNOW SATURDAY NIGHT ROUGHLY WEST OF HIGHWAY 83. ON SUNDAY...THE MAIN
SHOT OF ARCTIC AIR WILL PUSH INTO THE FORECAST AREA SOMETIME DURING
THE LATE MORNING/EARLY AFTERNOON HOURS. AS THE ARCTIC AIR PUSHES
SOUTHWARD SUNDAY...STILL CANNOT RULE OUT SOME LIGHT SNOW IN
ASSOCIATION WITH THE ARCTIC FROPA AND WILL CONTINUE TO MENTION IT.
TEMPERATURES WILL BE TRICKY SUNDAY GIVEN THE TIMING OF THE
FRONT...AS HIGHS WILL OCCUR DURING THE MORNING IN THE NORTH AND
AROUND MIDDAY IN THE SOUTH. ON SUNDAY AFTERNOON STRONG COLD AIR
ADVECTION...WILL INCREASE NORTHERLY WINDS WHICH WILL COMBINE WITH
THE BITTERLY COLD AIR TO PRODUCE WIND CHILLS RANGING FROM 20 TO 40
BELOW ZERO SUNDAY EVENING. THESE READINGS MAY DIP TO BELOW 40 BELOW
IN THE NORTH BY 12Z MONDAY. DECIDED TO HOIST A WIND CHILL WATCH
ALONG AND NORTH OF HIGHWAY 92 FROM MIDDAY SUNDAY THROUGH MIDDAY
MONDAY...AS WIND CHILLS OF 30 TO 45 BELOW ZERO APPEAR POSSIBLE IN
THESE AREAS. COLD TEMPERATURES WILL CARRY OVER INTO MONDAY...HOWEVER
WINDS ARE EXPECTED TO BEGIN TO RELAX MONDAY AFTERNOON AS HIGH
PRESSURE BEGINS TO BUILD SOUTH INTO THE MISSOURI VALLEY.
TEMPERATURES MONDAY MORNING WILL RANGE FROM -15 IN THE NORTH TO
AROUND -3 IN FAR SWRN NEBRASKA. READINGS WILL REBOUND BACK TO THE
SINGLE DIGITS AND TEENS MONDAY AFTERNOON AS THE CORE OF THE ARCTIC AIR IS
SHOVED EAST INTO THE MISSISSIPPI VALLEY AND UPPER MIDWEST.
MONDAY NIGHT THROUGH FRIDAY...THE MID RANGE MODEL SOLUTIONS CONTINUE
TO HINT AT A PATTERN SHIFT NEXT WEEK...TO A MORE ZONAL PATTERN. THIS
WILL ALLOW WARMER PACIFIC AIR TO INFILTRATE THE WESTERN AND CENTRAL
CONUS...LEADING TO NORMAL TO ABOVE NORMAL TEMPERATURES NEXT WEEK.
THE ONE DAY WITH SLIGHTLY COOLER TEMPS WILL BE WEDNESDAY AS A
DISTURBANCE AND WEAK FRONTAL BOUNDARY PUSHES THROUGH THE NORTHERN
PLAINS. THIS WILL BE A GLANCING BLOW OF ARCTIC AIR...SO ITS IMPACTS
ON TEMPS WILL BE FAIRLY MINIMAL. H85 TEMPS WEDNESDAY THROUGH FRIDAY
WILL GENERALLY RANGE FROM ZERO TO 5C...SO HIGHS WILL GENERALLY BE IN
THE 30S WITH SOME 40S OVER SWRN NEBRASKA. DRY CONDS WILL CONTINUE IN
THE EXTENDED AS NO SIGNIFICANT CUTOFF SYSTEMS OR DISTURBANCES WILL
TRACK ACROSS THE CENTRAL PLAINS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1116 PM CST FRI JAN 3 2014
IT LOOKS LIKE MVFR SHOULD BECOME FAIRLY WIDESPREAD ONCE THE ARCTIC
FRONT CURRENTLY MOVING THROUGH WRN SD SWEEPS INTO THE FCST AREA
OVERNIGHT. THE RAP AND NAM MODELS HOLD THIS STRATUS IN PLACE
THROUGHOUT THE DAY SATURDAY WHILE THE GEM...GFS AND ECM MIX THESE
CLOUDS OUT. THE FORECAST SIDES WITH THE LATTER 3 MODELS FOR A MIX
OF MVFR AND VFR SATURDAY.
NOTE THAT LAPSE RATES WILL REMAIN QUITE STEEP SUPPORTING THE
DEVELOPMENT OF ISOLATED TO SCATTERED SNOW SHOWER COVERAGE
OVERNIGHT THROUGH SATURDAY EVENING WHICH COULD PRODUCE LOCAL IFR
CONDITIONS...MAINLY ALONG AND WEST OF HIGHWAY 61.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WIND CHILL WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY MORNING
FOR NEZ004>010-022>029-035>038-094.
&&
$$
SYNOPSIS...CLB
SHORT TERM...MASEK
LONG TERM...CLB
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1145 AM CST SAT JAN 4 2014
.UPDATE...AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 1009 AM CST SAT JAN 4 2014/
MAINLY CLEAR SKIES ACROSS THE MIDSOUTH...WILL ALLOW FOR HIGH
TEMPS TO BE A FEW DEGREES WARMER WITH MORE SUN THROUGH THE REST OF
THE MORNING AND INTO THE EARLY AFTERNOON BEFORE CLOUDS START TO
DEVELOP.SOUTHERLY FLOW WILL HELP WITH THIS AS WELL. HAVE BUMPED
AFTERNOON HIGHS ACCORDINGLY...AND DEWPTS WITH LATEST RUC DATA AS
EACH SHOULD CLIMB STEADILY AND LIKELY A BIT FASTER THAN PREVIOUS
FORECAST. -ABS
PREV DISCUSSION... /ISSUED 528 AM CST SAT JAN 4 2014/
UPDATE...
UPDATED FOR 12Z AVIATION DISCUSSION.
PREV DISCUSSION... /ISSUED 450 AM CST SAT JAN 4 2014/
DISCUSSION...
CURRENTLY...TEMPERATURES ARE HOLDING STEADY OR RISING ACROSS MOST
AREA DUE TO AN INCREASING SOUTHERLY FLOW AHEAD OF THE DEVELOPING
SYSTEM OVER THE SOUTHERN PLAINS. SOME AREAS OF NE MS ARE STILL
DROPPING SINCE WINDS THERE ARE STILL LIGHT DUE TO THE PROXIMITY OF
THE RETREATING SURFACE HIGH. SKIES ARE MOSTLY CLEAR WITH JUST A
FEW HIGH CLOUDS ACROSS THE NORTH.
TODAY...TAKE ADVANTAGE. MILDER SOUTHERLY FLOW ACROSS THE REGION
AND A GOOD DEAL OF SUNSHINE...ESPECIALLY THIS MORNING...WILL ALLOW
TEMPS TO CLIMB CLOSE TO NORMAL. MID AND HIGH CLOUDS WILL BE ON THE
INCREASE THIS AFTERNOON AS LOW PRESSURE WILL STARTS TO ORGANIZE
NEAR THE RED RIVER VALLEY ALONG THE DEVELOPING ARCTIC FRONT. THE
POLAR VORTEX WILL CONTINUE DROPPING SOUTH WITH VERY COLD AIR PUSHING
INTO THE NORTHERN U.S.
TONIGHT...LOW PRESSURE WILL MOVE NORTHEAST ALONG THE STRENGTHENING
ARCTIC FRONT AND MOVE INTO EASTERN ARKANSAS LATE TONIGHT. RAIN WILL
DEVELOP AND SPREAD OVER THE REGION...ESPECIALLY AFTER MIDNIGHT.
TOWARD SUNRISE RAIN MAY START TO CHANGE TO SNOW ACROSS NE AR AS
COLD AIR BEGINS TO SEEP IN. LOWS TEMPS WILL BE QUITE A BIT MILDER
THANKS TO THE SOUTHERLY FLOW...IN THE 30S TO AROUND 40.
SUNDAY...BIG CHANGE IN STORE. LOW PRESSURE WILL MOVE TO THE TN
RIVER BY 18Z AND A POTENT SHORTWAVE WILL RAPIDLY KICK THE ARCTIC
FRONT EAST IN THE WAKE OF THE SURFACE LOW. TEMPS WILL COOL
RAPIDLY INTO THE 20S AS GUSTY NORTHWEST WINDS DEVELOP. RAIN WILL
CHANGE QUICKLY TO SNOW. THERE COULD BE A BRIEF PERIOD OF SLEET AS
THE COLD AIR AT THE SURFACE RUNS AHEAD OF THE COLD AIR ALOFT
LEAVING A WEAK WARM LAYER AROUND 5KFT. THIS WILL NOT LAST LONG
THOUGH. RIGHT NOW IT LOOKS LIKE THE ARCTIC FRONT WILL BE MOVING
INTO THE NW CORNER OF THE MIDSOUTH JUST BEFORE 12Z...MS RIVER
AROUND 18Z AND NE MS BY MID AFTERNOON. MODEL SOUNDINGS SHOW
FAIRLY DEEP MOISTURE FOR A FEW HOURS BEHIND THE FRONT. THIS
COMBINED WITH A POTENT MID LEVEL SHORTWAVE WILL PRODUCE
ACCUMULATING SNOW...ESPECIALLY ACROSS THE NORTHERN TIER WHERE THE
WATCH IS IN EFFECT. AN INCH OR TWO LOOKS POSSIBLE IN MEMPHIS WITH
LESSER AMOUNTS TO THE SOUTH. THE SNOW COMBINED WITH THE RAPIDLY
FALLING TEMPS AND WIND WILL RESULT IN A FLASH FREEZE WITH ROADWAYS
AND BRIDGES BECOMING SLICK QUICKLY.
SUNDAY NIGHT...LINGERING SNOW WILL TAPER OFF ACROSS EASTERN
SECTIONS DURING THE EVENING THOUGH FLURRIES WILL CONTINUE AS VERY
COLD AIR ADVECTS IN ON GUSTY NW WINDS. THE POLAR VORTEX WILL MOVE
INTO THE GREAT LAKES WHILE THE COLDEST AIR SINCE FEB 1996 SETTLES
OVER THE MIDSOUTH. 850MB TEMPS OF -20C OR LOWER AND 1000-500MB
THICKNESS VALUES APPROACHING 500DM. DESPITE THE WIND AND SOME
CLOUDS TEMPS WILL FALL INTO THE SINGLE DIGITS ACROSS MUCH OF THE
AREA BY MONDAY MORNING. WIND CHILLS WILL DROP TO BELOW ZERO ACROSS
THE ENTIRE AREA AND BELOW MINUS 10 NORTH OF I-40. NOW IS THE TIME
TO THINK ABOUT THOSE PIPES.
MONDAY THROUGH TUESDAY NIGHT...VERY COLD. MONDAY WILL BE THE
FIRST DAY MEMPHIS DOES NOT GET OUT OF THE TEENS SINCE FEB 1996.
PLACES UP NORTH WILL PROBABLY STAY IN THE SINGLE DIGITS. MONDAY
NIGHT WILL BE ANOTHER VERY COLD NIGHT AS SURFACE HIGH PRESSURE
WILL BE CENTERED ON THE MIDSOUTH. ANY SNOW ON THE GROUND WILL ONLY
AID RADIATIONAL COOLING AND HELP DROP TEMPS EVEN FURTHER. LOTS OF
SINGLE DIGITS EXPECTED WITH SOME BELOW ZERO READINGS POSSIBLE. THE
COLDEST AIR STARTS TO RETREAT EAST ON TUESDAY THOUGH TEMPS WILL
STILL BE QUITE COLD...IN THE 20S.
WEDNESDAY THROUGH FRIDAY...OVERRUNNING PATTERN SETS UP OVER THE
RETREATING ARCTIC AIRMASS WITH PRECIP CHANCES INCREASING. A
WINTRY MIX WILL BE POSSIBLE ACROSS NORTHERN AREAS WEDNESDAY
THROUGH THURSDAY MORNING WITH CHANCES FOR RAIN ELSW. ENOUGH
WARMING OCCURS FOR ONLY RAIN BY MID MORNING THURSDAY THROUGH
FRIDAY.
SJM
&&
.AVIATION...18Z TAFS
IMPORTANT CHANGES TO THE PREVIOUS SET OF TAFS INCLUDE THE
INTRODUCTION OF RA/SN TOWARDS THE END OF THE PERIOD AND 5-10 KT
LESS WIND SHEAR. VFR CONDITIONS WILL CONTINUE THROUGH THE FIRST
HALF OF THE TAF PERIOD WITH CIGS DECREASING TO MVFR BY 03Z AT
JBR...5Z AT MEM AND TUP AND...6Z AT MKL. RAIN WILL BEGIN AN HOUR
OR SO AFTER MVFR CIGS MOVE IN AT ALL SITES. THE CHANGEOVER TO SNOW
LOOKS TO BE DELAYED A BIT IN LATEST GUIDANCE. SO WILL KEEP ALL
PRECIPITATION RA THROUGH 14Z AT JBR...15Z AT MEM AND 16Z AT MKL.
IFR CIGS ARE EXPECTED AT JBR...MEM AND MKL BEFORE SUNRISE.
GENERALLY SOUTHERLY WINDS WILL BE SUSTAINED 12-18 KTS AND GUSTS
IN THE 18-26 KT RANGE. DECREASE 10 10-15KT AND LESS GUSTY
OVERNIGHT. OVERNIGHT...WHEN WINDS ARE LIGHTEST AT THE
SURFACE...THE WIND SHEAR THREAT WILL BE GREATEST. WIND SHIFT IS
EXPECTED AT JBR PRIOR TO 18S.
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 49 39 43 10 / 10 60 100 20
MKL 46 38 42 5 / 0 50 100 30
JBR 44 35 35 6 / 10 90 100 20
TUP 48 38 48 9 / 0 30 100 40
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WINTER STORM WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
FOR CLAY-GREENE-LAWRENCE-RANDOLPH.
MO...WINTER STORM WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
FOR DUNKLIN-PEMISCOT.
MS...NONE.
TN...WINTER STORM WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING
FOR CARROLL-DYER-GIBSON-HENRY-LAKE-OBION-WEAKLEY.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1009 AM CST SAT JAN 4 2014
.UPDATE...
MAINLY CLEAR SKIES ACROSS THE MIDSOUTH...WILL ALLOW FOR HIGH TEMPS
TO BE A FEW DEGREES WARMER WITH MORE SUN THROUGH THE REST OF THE
MORNING AND INTO THE EARLY AFTERNOON BEFORE CLOUDS START TO
DEVELOP.SOUTHERLY FLOW WILL HELP WITH THIS AS WELL. HAVE BUMPED
AFTERNOON HIGHS ACCORDINGLY...AND DEWPTS WITH LATEST RUC DATA AS
EACH SHOULD CLIMB STEADILY AND LIKELY A BIT FASTER THAN
PREVIOUS FORECAST. -ABS
&&
.PREV DISCUSSION... /ISSUED 528 AM CST SAT JAN 4 2014/
UPDATE...
UPDATED FOR 12Z AVIATION DISCUSSION.
PREV DISCUSSION... /ISSUED 450 AM CST SAT JAN 4 2014/
DISCUSSION...
CURRENTLY...TEMPERATURES ARE HOLDING STEADY OR RISING ACROSS MOST
AREA DUE TO AN INCREASING SOUTHERLY FLOW AHEAD OF THE DEVELOPING
SYSTEM OVER THE SOUTHERN PLAINS. SOME AREAS OF NE MS ARE STILL
DROPPING SINCE WINDS THERE ARE STILL LIGHT DUE TO THE PROXIMITY OF
THE RETREATING SURFACE HIGH. SKIES ARE MOSTLY CLEAR WITH JUST A
FEW HIGH CLOUDS ACROSS THE NORTH.
TODAY...TAKE ADVANTAGE. MILDER SOUTHERLY FLOW ACROSS THE REGION
AND A GOOD DEAL OF SUNSHINE...ESPECIALLY THIS MORNING...WILL ALLOW
TEMPS TO CLIMB CLOSE TO NORMAL. MID AND HIGH CLOUDS WILL BE ON THE
INCREASE THIS AFTERNOON AS LOW PRESSURE WILL STARTS TO ORGANIZE
NEAR THE RED RIVER VALLEY ALONG THE DEVELOPING ARCTIC FRONT. THE
POLAR VORTEX WILL CONTINUE DROPPING SOUTH WITH VERY COLD AIR PUSHING
INTO THE NORTHERN U.S.
TONIGHT...LOW PRESSURE WILL MOVE NORTHEAST ALONG THE STRENGTHENING
ARCTIC FRONT AND MOVE INTO EASTERN ARKANSAS LATE TONIGHT. RAIN WILL
DEVELOP AND SPREAD OVER THE REGION...ESPECIALLY AFTER MIDNIGHT.
TOWARD SUNRISE RAIN MAY START TO CHANGE TO SNOW ACROSS NE AR AS
COLD AIR BEGINS TO SEEP IN. LOWS TEMPS WILL BE QUITE A BIT MILDER
THANKS TO THE SOUTHERLY FLOW...IN THE 30S TO AROUND 40.
SUNDAY...BIG CHANGE IN STORE. LOW PRESSURE WILL MOVE TO THE TN
RIVER BY 18Z AND A POTENT SHORTWAVE WILL RAPIDLY KICK THE ARCTIC
FRONT EAST IN THE WAKE OF THE SURFACE LOW. TEMPS WILL COOL
RAPIDLY INTO THE 20S AS GUSTY NORTHWEST WINDS DEVELOP. RAIN WILL
CHANGE QUICKLY TO SNOW. THERE COULD BE A BRIEF PERIOD OF SLEET AS
THE COLD AIR AT THE SURFACE RUNS AHEAD OF THE COLD AIR ALOFT
LEAVING A WEAK WARM LAYER AROUND 5KFT. THIS WILL NOT LAST LONG
THOUGH. RIGHT NOW IT LOOKS LIKE THE ARCTIC FRONT WILL BE MOVING
INTO THE NW CORNER OF THE MIDSOUTH JUST BEFORE 12Z...MS RIVER
AROUND 18Z AND NE MS BY MID AFTERNOON. MODEL SOUNDINGS SHOW
FAIRLY DEEP MOISTURE FOR A FEW HOURS BEHIND THE FRONT. THIS
COMBINED WITH A POTENT MID LEVEL SHORTWAVE WILL PRODUCE
ACCUMULATING SNOW...ESPECIALLY ACROSS THE NORTHERN TIER WHERE THE
WATCH IS IN EFFECT. AN INCH OR TWO LOOKS POSSIBLE IN MEMPHIS WITH
LESSER AMOUNTS TO THE SOUTH. THE SNOW COMBINED WITH THE RAPIDLY
FALLING TEMPS AND WIND WILL RESULT IN A FLASH FREEZE WITH ROADWAYS
AND BRIDGES BECOMING SLICK QUICKLY.
SUNDAY NIGHT...LINGERING SNOW WILL TAPER OFF ACROSS EASTERN
SECTIONS DURING THE EVENING THOUGH FLURRIES WILL CONTINUE AS VERY
COLD AIR ADVECTS IN ON GUSTY NW WINDS. THE POLAR VORTEX WILL MOVE
INTO THE GREAT LAKES WHILE THE COLDEST AIR SINCE FEB 1996 SETTLES
OVER THE MIDSOUTH. 850MB TEMPS OF -20C OR LOWER AND 1000-500MB
THICKNESS VALUES APPROACHING 500DM. DESPITE THE WIND AND SOME
CLOUDS TEMPS WILL FALL INTO THE SINGLE DIGITS ACROSS MUCH OF THE
AREA BY MONDAY MORNING. WIND CHILLS WILL DROP TO BELOW ZERO ACROSS
THE ENTIRE AREA AND BELOW MINUS 10 NORTH OF I-40. NOW IS THE TIME
TO THINK ABOUT THOSE PIPES.
MONDAY THROUGH TUESDAY NIGHT...VERY COLD. MONDAY WILL BE THE
FIRST DAY MEMPHIS DOES NOT GET OUT OF THE TEENS SINCE FEB 1996.
PLACES UP NORTH WILL PROBABLY STAY IN THE SINGLE DIGITS. MONDAY
NIGHT WILL BE ANOTHER VERY COLD NIGHT AS SURFACE HIGH PRESSURE
WILL BE CENTERED ON THE MIDSOUTH. ANY SNOW ON THE GROUND WILL ONLY
AID RADIATIONAL COOLING AND HELP DROP TEMPS EVEN FURTHER. LOTS OF
SINGLE DIGITS EXPECTED WITH SOME BELOW ZERO READINGS POSSIBLE. THE
COLDEST AIR STARTS TO RETREAT EAST ON TUESDAY THOUGH TEMPS WILL
STILL BE QUITE COLD...IN THE 20S.
WEDNESDAY THROUGH FRIDAY...OVERRUNNING PATTERN SETS UP OVER THE
RETREATING ARCTIC AIRMASS WITH PRECIP CHANCES INCREASING. A
WINTRY MIX WILL BE POSSIBLE ACROSS NORTHERN AREAS WEDNESDAY
THROUGH THURSDAY MORNING WITH CHANCES FOR RAIN ELSW. ENOUGH
WARMING OCCURS FOR ONLY RAIN BY MID MORNING THURSDAY THROUGH
FRIDAY.
SJM
AVIATION...
12Z TAFS
VFR CONDITIONS WILL CONTINUE THROUGH MOST OF THE TAF PERIOD...WITH
CIGS DECREASING TO MVFR AND IFR TONIGHT AS AN ARCTIC COLD FRONT
APPROACHES. RAIN WILL ALSO DEVELOP AHEAD OF THE BOUNDARY...WITH
JBR SEEING THE ACTIVITY FIRST. STRONG SOUTH WINDS WILL BE THE MAIN
WEATHER CONCERN...WITH SUSTAINED WINDS OF 12-18 KTS AND GUSTS
IN THE 18-26 KT RANGE...DEPENDING ON SITE. AS WINDS DECREASE
SOME NEAR SUNSET WIND SHEAR IS EXPECTED TO DEVELOP AT MEM...JBR
AND MKL. FINALLY JUST BEYOND THIS PERIOD RAIN WILL BE CHANGING TO
ACCUMULATING SNOW BEHIND THE FRONT AT JBR FIRST...THEN MEM AND MKL.
JAB
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 49 39 43 10 / 10 60 100 30
MKL 46 38 42 5 / 0 50 100 40
JBR 44 35 35 6 / 10 90 100 20
TUP 48 38 48 9 / 0 30 100 40
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WINTER STORM WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
FOR CLAY-GREENE-LAWRENCE-RANDOLPH.
MO...WINTER STORM WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
FOR DUNKLIN-PEMISCOT.
MS...NONE.
TN...WINTER STORM WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING
FOR CARROLL-DYER-GIBSON-HENRY-LAKE-OBION-WEAKLEY.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1129 PM CST FRI JAN 3 2014
.DISCUSSION...
UPDATED AVIATION.
&&
.AVIATION...
LATEST SATELLITE IMAGERY SHOWS CLEAR SKY WITH JUST A FEW 4000 FOOT
CLOUDS COMING IN OFF THE GULF. SOME OF THESE COULD CREEP INTO LBX
AND GLS OVERNIGHT AS THEY ADVECT NORTHWARD GIVEN ONSHORE LOW LEVEL
FLOW. MODEL SOUNDINGS AND MOS GUIDANCE SUGGEST POSSIBILITY OF
MVFR CEILING DEVELOPMENT VERY LATE TONIGHT AND SATURDAY MORNING
FOR AT LEAST NORTHERN TAF SITES...INCLUDING CLL...UTS AND
CXO...AND HAVE INCLUDED THIS SCENARIO FOR THOSE LOCATIONS.
ELSEWHERE EXPECT A GENERAL INCREASE IN CLOUD COVER MAINLY ON
SATURDAY WITH BROKEN TO OVERCAST CONDITIONS BY MIDDAY. CLOUD
HEIGHT STILL DIFFICULT TO CALL...AS EXPECT SOMEWHERE ON THE 3000
TO 4000 FOOT RANGE FOR MOST PART...TRENDING LOWER AS SATURDAY
AFTERNOON AND EVENING EVOLVE. SOME OF THE GUIDANCE AND MODEL
SOUNDINGS WOULD ARGUE FOR LOWER CEILINGS RIGHT AWAY...BUT THIS
GUIDANCE CAN BE OVERLY PESSIMISTIC AT TIMES. 46
&&
.PREV DISCUSSION... /ISSUED 720 PM CST FRI JAN 3 2014/
UPDATE...
SEE DISCUSSION FOR EVENING UPDATE.
DISCUSSION...
CLEAR SKIES ACROSS MUCH OF THE CWA THIS EVENING HAS ALLOWED
TEMPERATURES TO DROP QUICKLY. A COUPLE OF RURAL LOCATIONS HAVE HAD
WINDS DECOUPLE WITH CURRENT TEMPERATURES SITTING AT JUST BELOW 40
DEGREES. STILL THINK ONSHORE WINDS WILL START TO SLOW DOWN THE
SLIDE IN TEMPERATURES THIS EVENING WITH THE WESTERN ZONES AND
COASTAL COUNTIES HAVING TEMPERATURES STARTING TO LEVEL OFF BEFORE
SUNRISE. GFS AND ECMWF ARE TO FAST WITH THE MOISTURE RETURN WHILE
THE RAP IS MORE ON TARGET. GIVEN THIS HAVE LEANED TOWARDS THE RAP.
BECAUSE OF THE TRENDS ABOVE HAVE UPDATED MIN T GRIDS. REST OF
FORECAST LOOKS ON TRACK. 23
PREV DISCUSSION... /ISSUED 546 PM CST FRI JAN 3 2014/
DISCUSSION...
UPDATED AVIATION DISCUSSION.
AVIATION...
CLEAR SKY WITH SOUTHEAST WIND AT ALL TAF SITES AT THE MOMENT. AS
ONSHORE FLOW CONTINUES WILL SEE AN INCREASE IN CLOUDS VERY LATE
TONIGHT AND SATURDAY WITH OVERCAST CONDITIONS EXPECTED SATURDAY
AFTERNOON MOST SITES. SOME UNCERTAINTY IN RESULTING CEILINGS BUT
THINK WILL MOSTLY START OUT VFR WITH CLOUD BASE AROUND 4000 FEET
THEN LOWER INTO MVFR RANGE DURING THE AFTERNOON. CLOUDS OVER THE
GULF NOW ARE IN THAT 4000 FOOT RANGE LENDING SOME SUPPORT TO THIS
AND GFS MOS GENERALLY SUPPORTS THIS SCENARIO AS WELL. SOME OF THE
OTHER MODEL FIELDS WOULD SUGGEST MVFR CIGS PERHAPS ARRIVING A
LITTLE EARLIER SO WILL HAVE TO MONITOR.
ONLY EXCEPTION TO ALL THE ABOVE IS CLL WHERE DID BITE ON SOME
LOWER MVFR CIGS AROUND SUNRISE SATURDAY BASED ON MAJORITY OF
GUIDANCE. 46
PREV DISCUSSION... /ISSUED 331 PM CST FRI JAN 3 2014/
DISCUSSION...
A HIGHLY AMPLIFIED PATTERN ALOFT WILL LEAD TO A PUSH OF A VERY
COLD AIR MASS INTO SE TX EARLY NEXT WEEK. THIS WILL BE PRECEDED BY
A WARMUP TONIGHT AND SATURDAY AS ONSHORE WINDS HELP RETURN GULF
MOISTURE TO THE AREA. STRONG WARM AIR ADVECTION ON SATURDAY WILL
LEAD TO ABOVE NORMAL HIGH TEMPERATURES. THE MODELS ARE THEN
CONSISTENT IN PUSHING A COLD FRONT QUICKLY THROUGH THE AREA SUNDAY
MORNING. THE FRONT IS EXPECTED TO BE OFF THE COAST BEFORE NOON.
THE COLDEST AIR MASS OF THE SEASON IS THEN EXPECTED. MODEL
GUIDANCE STILL DIFFERS...HOWEVER THERE IS ENOUGH CONSENSUS TO SAY
WITH CONFIDENCE THAT MOST AREAS WILL EXPERIENCE AT LEAST FREEZING
OVERNIGHT LOW TEMPERATURES SUNDAY NIGHT AND MONDAY MORNING TOWARD
THE COAST...WITH LOCATIONS ALONG AND NORTH OF A LINE FROM LIBERTY
TO THE WOODLANDS TO COLUMBUS EXPERIENCING MID 20S. MONDAY NIGHT
AND EARLY TUESDAY MORNING WILL LIKELY BE THE COLDEST NIGHT AS THE
CENTER OF THE SURFACE HIGH PRESSURE RIDGE SETTLES OVER THE INLAND
COUNTIES. LOWER 20S LOOKS LIKELY ALONG AND NORTH OF A LINE FROM
LIBERTY TO THE WOODLANDS TO COLUMBUS. METRO HOUSTON MAY SEE
TEMPERATURES FALL INTO THE MID 20S AND UPPER 20S...WITH HARRIS
COUNTY LIKELY EXPERIENCING LOWER 20S IN THE NORTHWEST...MID 20S IN
THE CENTRAL...AND UPPER 20S TOWARD GALVESTON BAY. LOWS BETWEEN 28
AND 32 LOOK TO BE COMMON ALONG THE IMMEDIATE COAST.
WINDS BY TUESDAY AFTERNOON WILL BECOME ONSHORE AND A COMBINATION
OF WARM AIR ADVECTION AND MOISTURE ADVECTION WILL LEAD TO A
WARMING TREND PROBABLY THE END OF THE WORK WEEK.
40
AVIATION...
DID NOT MAKE ANY MAJOR CHANGES WITH THE 18Z TAFS. ONSHORE WINDS HAVE
RETURNED AREAWIDE WITH ONLY HIGH CLOUDS MENTIONED. OTHERWISE VFR. 41
MARINE...
ONSHORE WINDS WILL CONTINUE TO DEVELOP ACROSS THE COASTAL WATERS DUR-
ING THE OVERNIGHT HRS AS HIGH PRESSURE MOVES INTO THE E/NE U.S.. NOT
A LOT OF ISSUES FOR THE MARINE AREAS UNTIL SUN WITH THE ARRIVAL/PASS-
AGE OF THE NEXT COLD FRONT. THIS IS SYSTEM IS EXPECTED TO BRING VERY
STRONG/GUSTY NORTH WINDS TO THE AREA AND SMALL CRAFT ADVISORIES WILL
LIKELY BE REQUIRED BY SUN AFTN. 41
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 38 66 48 50 23 / 0 10 20 10 0
HOUSTON (IAH) 36 66 58 58 27 / 0 10 30 30 0
GALVESTON (GLS) 44 64 58 58 34 / 0 10 20 30 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS GREEN BAY WI
558 PM CST SUN JAN 5 2014
NEW INFORMATION ADDED TO UPDATE SECTION
.UPDATE...
ISSUED AT 554 PM CST SUN JAN 5 2014
NOT MEETING CRITERIA YET...BUT WL LET THE WIND CHILL WARNING GO
INTO EFFECT AS SCHEDULED AT 600 PM.
SUSPECT OUR OVERNIGHT MINS MIGHT BE A BIT LOW AND WIND MIGHT BE A
LITTLE HIGH...SO WIND CHILLS MAY NOT BE QUITE AS LOW AS WE HAVE IN
THE FCST. BUT THEY SHOULD STILL MAKE WARNING CRITERIA.
STILL WAITING FOR THE FRONTAL WAVE TO LIFT OFF TO THE NE FOR THE
CORE OF THE COLD TO OVERSPREAD THE AREA. WL SEE HOW THINGS EVOLVE
DURING THE NEXT COUPLE HOURS...AND MAY MAKE SOME SML ADJUSTMENTS
TO THE FCST A LITTLE LATER THIS EVENING.
&&
.SHORT TERM...TONIGHT AND MONDAY
ISSUED AT 204 PM CST SUN JAN 5 2014
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A STRENGTHENING
AREA OF LOW PRESSURE MOVING NORTHEAST OVER THE OHIO VALLEY. A WIDE
SWATH OF HEAVY SNOW IS IMPACTING ST LOUIS TO THE THUMB OF MICHIGAN JUST
NORTH OF THE SURFACE LOW TRACK...AND IS NOT SHOWING ANY SIGNS OF
LIFTING INTO EAST-CENTRAL WISCONSIN. ALTOSTRATUS ON THE NORTHERN
PERIPHERY OF THIS SYSTEM IS MOVING ACROSS MUCH OF CENTRAL AND NORTHEAST
WISCONSIN AND IS PREVENTING ANY SUNSHINE TO OFFSET THE COLD
TEMPERATURES. READINGS THIS AFTERNOON REMAIN BELOW ZERO WEST OF A
WAUTOMA TO IRON MOUNTAIN LINE...WHERE WIND CHILLS ARE NEAR OR BELOW
WIND CHILL ADVISORY CRITERIA (-20F). FARTHER WEST...A LOBE OF THE
POLAR VORTEX IS DROPPING SOUTHEAST OVER THE DAKOTAS WHERE TEMPS ARE
IN THE TEENS BELOW ZERO WITH WINDS GUSTING OVER 40 KTS. ALSO SEEING
LOWER VSBYS WITHIN SOME CLOUD COVER IN THIS REGION...BUT THINK MUCH
OF THESE OBS CAN BE ATTRIBUTED TO BLOWING SNOW. AS THE POLAR VORTEX
AND ASSOCIATED ARCTIC AIR MOVES ACROSS THE REGION...LIGHT SNOW
CHANCES AND WIND CHILL HEADLINES ARE THE MAIN FORECAST CONCERNS.
TONIGHT...THE LOW PRESSURE SYSTEM WILL MOVE FROM THE OHIO VALLEY TO THE
EASTERN GREAT LAKES THIS EVENING. CYCLONIC FLOW AROUND THE LOW WILL
DELAY THE BITTERLY COLD ARCTIC AIR FROM REACHING NORTHEAST WISCONSIN
UNTIL LATE IN THE EVENING OR EARLY OVERNIGHT. OTHERWISE A LOBE OF
THE POLAR VORTEX WILL SWING EAST FROM THE NORTHERN MISSISSIPPI
VALLEY TO NORTHEAST WISCONSIN. AS THIS OCCURS...SHOULD SEE AN AREA
OF LOW AND MID CLOUDS MOVE EAST OVER THE FORECAST AREA. SINCE THE
LOWER VSBYS OVER THE DAKOTAS HAS THE LOOK OF BLOWING SNOW...WILL
REMOVE THE FLURRY MENTION AFTER MIDNIGHT. HOWEVER...MODELS TRY TO
RETURN SOME MOISTURE FROM THE SOUTH AHEAD OF THE SHORTWAVE LOBE AND
PRODUCE LIGHT SNOW OR FLURRIES ALONG THE LAKE MICHIGAN SHORELINE
LATE TONIGHT. THIS POSSIBILITY STILL LOOKS REASONABLE AND WILL
LEAVE IN THE FORECAST. OTHERWISE...THE MAIN STORY WILL BE THE
ADVECTION OF THE COLDEST AIR THE REGION HAS OBSERVED IN YEARS.
850MB TEMPS WILL FALL INTO THE -25C TO -35C RANGE MY 12Z MON WHICH
WILL BRING IN SURFACE TEMPS FROM 30 BELOW OVER NORTH-CENTRAL
WISCONSIN TO ABOUT 15 BELOW AT THE LAKE MICHIGAN SHORELINE.
COMBINED WITH WINDS GUSTING TO 25 TO 30 MPH...PROJECTED WIND CHILLS
WILL FALL INTO THE 40 TO 55 DEGREES BELOW ZERO RANGE. EASTERN
SECTIONS MAY NOT REACH WIND CHILL WARNING CRITERIA UNTIL AFTER
MIDNIGHT...BUT THEY WILL BE FALLING RAPIDLY THROUGH THE EVENING...SO
WILL LEAVE THE WARNING START TIMES ALONE TO INCLUDE THE ADVISORY
RAMP UP TIME.
MONDAY...THE POLAR VORTEX WILL BE EXITING NORTHEAST WISCONSIN EARLY
IN THE MORNING AND WILL LEAVE A SMALL CHANCE OVER DOOR COUNTY TO
ACCOUNT FOR THAT. SHOULD SEE A PERIOD OF DECREASING CLOUDS UNTIL
MID AND HIGH CLOUDS SLIDE IN FROM THE NORTH DURING THE AFTERNOON.
NOT SURE HOW MUCH OF THESE CLOUDS WILL HOLD TOGETHER...SO WILL KEEP
SKIES IN THE PARTLY CLOUDY RANGE. ARCTIC HIGH PRESSURE WILL SLIDE
SOUTHEAST TOWARDS THE CENTRAL PLAINS WHICH SHOULD KEEP A TIGHT
PRESSURE GRADIENT IN PLACE. COMBINED WITH TEMPERATURES IN THE
NEGATIVE TEENS BELOW ZERO FOR HIGHS...WIND CHILLS WILL REMAIN IN THE
35 TO 45 DEGREES BELOW ZERO RANGE. WIND CHILL WARNINGS WILL
CONTINUE AS A RESULT.
.LONG TERM...MONDAY NIGHT THROUGH SUNDAY
ISSUED AT 204 PM CST SUN JAN 5 2014
THE BITTER COLD REGIME OF ARCTIC AIR WILL STUBBORNLY DIMINISH
THIS WEEK AS THE UPPER FLOW TURNS MORE ZONAL WITH THE INTRODUCTION
OF WESTERLY PACIFIC FLOW AND MILDER CONDITIONS BY NEXT WEEKEND.
EVEN THOUGH THE CENTER OF THE POLAR VORTEX IS LIFTING NORTHEAST OF
THE AREA MONDAY NIGHT INTO EARLY TUESDAY...BITTER COLD AIR MASS
LEFT IN ITS WAKE COMBINED WITH WEST WINDS 10 TO 20 MPH WILL
CONTINUE TO PRODUCE WARNING WIND CHILL NUMBERS THROUGH A GOOD
PORTION OF TUESDAY BEFORE SUBSIDING TO ADVISORY CRITERIA IN THE
AFTERNOON.
HIGH PRESSURE RIDGE BEGINS TO SETTLES OVER THE AREA LATER TUESDAY
AFTERNOON INTO TUESDAY NIGHT. EVEN THOUGH 850 TEMPS BEGIN TO
MODIFY...EXPECTED CLEAR SKIES AND LIGHT WINDS WILL ALLOW TEMPS TO
PLUMMET WELL BELOW ZERO AGAIN. DEPENDING ON WINDS...PARTS OF THE
THE AREA MAY STILL WARRANT WIND CHILL ADVISORY HEADLINES. THE COLD
HIGH PRESSURE REMAINS SETTLED OVER THE REGION WEDNESDAY NIGHT AND
THURSDAY FOR CONTINUED BELOW NORMAL SUB ZERO TEMPERATURES. A WEAK
SYSTEM IS PROGGED TO PASS SOUTH OF THE AREA WEDNESDAY NIGHT AND
THURSDAY...HAS TRENDED SOUTH LEAVING THE AREA MORE IN THE COLD
AIR MASS.
WAA PATTERN BEGINS IN EARNEST LATER THURSDAY INTO FRIDAY WITH
TEMPERATURES APPROACHING THE FREEZING MARK FOR THE WEEKEND. DUE
TO THE ZONAL FLOW...MODELS ARE PRODUCING DIFFERENT SOLUTIONS WITH
TIMING OF WEAK SHORT WAVES PASSING OVER OR NEAR THE GREAT LAKES
REGION FRIDAY INTO SUNDAY. USUALLY THE PACIFIC SYSTEMS ARE ON THE
DRY SIDE BUT WITH H850 TEMPERATURES ABOVE ZERO THIS WEEKEND...PCPN
TYPE ISSUES WILL INCREASE.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 529 PM CST SUN JAN 5 2014
ARCTIC AIR BECOMING ESTABLISHED ACRS THE AREA. EXPECT OCNL MVFR
CIGS AS DEEP VORTEX SLIDES ACRS THE AREA LATE TNGT/EARLY MON.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
WIND CHILL WARNING UNTIL NOON CST TUESDAY FOR WIZ005-010>013-
018>022-030-031-035>040-045-048>050-073-074.
WIND CHILL ADVISORY UNTIL 6 PM CST THIS EVENING FOR WIZ005-
010>012-018-019-030-035-036.
&&
$$
UPDATE.........
SHORT TERM.....MPC
LONG TERM......TDH
AVIATION.......SKOWRONSKI
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
530 PM CST SUN JAN 5 2014
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND MONDAY
ISSUED AT 204 PM CST SUN JAN 5 2014
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A STRENGTHENING
AREA OF LOW PRESSURE MOVING NORTHEAST OVER THE OHIO VALLEY. A WIDE
SWATH OF HEAVY SNOW IS IMPACTING ST LOUIS TO THE THUMB OF MICHIGAN JUST
NORTH OF THE SURFACE LOW TRACK...AND IS NOT SHOWING ANY SIGNS OF
LIFTING INTO EAST-CENTRAL WISCONSIN. ALTOSTRATUS ON THE NORTHERN
PERIPHERY OF THIS SYSTEM IS MOVING ACROSS MUCH OF CENTRAL AND NORTHEAST
WISCONSIN AND IS PREVENTING ANY SUNSHINE TO OFFSET THE COLD
TEMPERATURES. READINGS THIS AFTERNOON REMAIN BELOW ZERO WEST OF A
WAUTOMA TO IRON MOUNTAIN LINE...WHERE WIND CHILLS ARE NEAR OR BELOW
WIND CHILL ADVISORY CRITERIA (-20F). FARTHER WEST...A LOBE OF THE
POLAR VORTEX IS DROPPING SOUTHEAST OVER THE DAKOTAS WHERE TEMPS ARE
IN THE TEENS BELOW ZERO WITH WINDS GUSTING OVER 40 KTS. ALSO SEEING
LOWER VSBYS WITHIN SOME CLOUD COVER IN THIS REGION...BUT THINK MUCH
OF THESE OBS CAN BE ATTRIBUTED TO BLOWING SNOW. AS THE POLAR VORTEX
AND ASSOCIATED ARCTIC AIR MOVES ACROSS THE REGION...LIGHT SNOW
CHANCES AND WIND CHILL HEADLINES ARE THE MAIN FORECAST CONCERNS.
TONIGHT...THE LOW PRESSURE SYSTEM WILL MOVE FROM THE OHIO VALLEY TO THE
EASTERN GREAT LAKES THIS EVENING. CYCLONIC FLOW AROUND THE LOW WILL
DELAY THE BITTERLY COLD ARCTIC AIR FROM REACHING NORTHEAST WISCONSIN
UNTIL LATE IN THE EVENING OR EARLY OVERNIGHT. OTHERWISE A LOBE OF
THE POLAR VORTEX WILL SWING EAST FROM THE NORTHERN MISSISSIPPI
VALLEY TO NORTHEAST WISCONSIN. AS THIS OCCURS...SHOULD SEE AN AREA
OF LOW AND MID CLOUDS MOVE EAST OVER THE FORECAST AREA. SINCE THE
LOWER VSBYS OVER THE DAKOTAS HAS THE LOOK OF BLOWING SNOW...WILL
REMOVE THE FLURRY MENTION AFTER MIDNIGHT. HOWEVER...MODELS TRY TO
RETURN SOME MOISTURE FROM THE SOUTH AHEAD OF THE SHORTWAVE LOBE AND
PRODUCE LIGHT SNOW OR FLURRIES ALONG THE LAKE MICHIGAN SHORELINE
LATE TONIGHT. THIS POSSIBILITY STILL LOOKS REASONABLE AND WILL
LEAVE IN THE FORECAST. OTHERWISE...THE MAIN STORY WILL BE THE
ADVECTION OF THE COLDEST AIR THE REGION HAS OBSERVED IN YEARS.
850MB TEMPS WILL FALL INTO THE -25C TO -35C RANGE MY 12Z MON WHICH
WILL BRING IN SURFACE TEMPS FROM 30 BELOW OVER NORTH-CENTRAL
WISCONSIN TO ABOUT 15 BELOW AT THE LAKE MICHIGAN SHORELINE.
COMBINED WITH WINDS GUSTING TO 25 TO 30 MPH...PROJECTED WIND CHILLS
WILL FALL INTO THE 40 TO 55 DEGREES BELOW ZERO RANGE. EASTERN
SECTIONS MAY NOT REACH WIND CHILL WARNING CRITERIA UNTIL AFTER
MIDNIGHT...BUT THEY WILL BE FALLING RAPIDLY THROUGH THE EVENING...SO
WILL LEAVE THE WARNING START TIMES ALONE TO INCLUDE THE ADVISORY
RAMP UP TIME.
MONDAY...THE POLAR VORTEX WILL BE EXITING NORTHEAST WISCONSIN EARLY
IN THE MORNING AND WILL LEAVE A SMALL CHANCE OVER DOOR COUNTY TO
ACCOUNT FOR THAT. SHOULD SEE A PERIOD OF DECREASING CLOUDS UNTIL
MID AND HIGH CLOUDS SLIDE IN FROM THE NORTH DURING THE AFTERNOON.
NOT SURE HOW MUCH OF THESE CLOUDS WILL HOLD TOGETHER...SO WILL KEEP
SKIES IN THE PARTLY CLOUDY RANGE. ARCTIC HIGH PRESSURE WILL SLIDE
SOUTHEAST TOWARDS THE CENTRAL PLAINS WHICH SHOULD KEEP A TIGHT
PRESSURE GRADIENT IN PLACE. COMBINED WITH TEMPERATURES IN THE
NEGATIVE TEENS BELOW ZERO FOR HIGHS...WIND CHILLS WILL REMAIN IN THE
35 TO 45 DEGREES BELOW ZERO RANGE. WIND CHILL WARNINGS WILL
CONTINUE AS A RESULT.
.LONG TERM...MONDAY NIGHT THROUGH SUNDAY
ISSUED AT 204 PM CST SUN JAN 5 2014
THE BITTER COLD REGIME OF ARCTIC AIR WILL STUBBORNLY DIMINISH
THIS WEEK AS THE UPPER FLOW TURNS MORE ZONAL WITH THE INTRODUCTION
OF WESTERLY PACIFIC FLOW AND MILDER CONDITIONS BY NEXT WEEKEND.
EVEN THOUGH THE CENTER OF THE POLAR VORTEX IS LIFTING NORTHEAST OF
THE AREA MONDAY NIGHT INTO EARLY TUESDAY...BITTER COLD AIR MASS
LEFT IN ITS WAKE COMBINED WITH WEST WINDS 10 TO 20 MPH WILL
CONTINUE TO PRODUCE WARNING WIND CHILL NUMBERS THROUGH A GOOD
PORTION OF TUESDAY BEFORE SUBSIDING TO ADVISORY CRITERIA IN THE
AFTERNOON.
HIGH PRESSURE RIDGE BEGINS TO SETTLES OVER THE AREA LATER TUESDAY
AFTERNOON INTO TUESDAY NIGHT. EVEN THOUGH 850 TEMPS BEGIN TO
MODIFY...EXPECTED CLEAR SKIES AND LIGHT WINDS WILL ALLOW TEMPS TO
PLUMMET WELL BELOW ZERO AGAIN. DEPENDING ON WINDS...PARTS OF THE
THE AREA MAY STILL WARRANT WIND CHILL ADVISORY HEADLINES. THE COLD
HIGH PRESSURE REMAINS SETTLED OVER THE REGION WEDNESDAY NIGHT AND
THURSDAY FOR CONTINUED BELOW NORMAL SUB ZERO TEMPERATURES. A WEAK
SYSTEM IS PROGGED TO PASS SOUTH OF THE AREA WEDNESDAY NIGHT AND
THURSDAY...HAS TRENDED SOUTH LEAVING THE AREA MORE IN THE COLD
AIR MASS.
WAA PATTERN BEGINS IN EARNEST LATER THURSDAY INTO FRIDAY WITH
TEMPERATURES APPROACHING THE FREEZING MARK FOR THE WEEKEND. DUE
TO THE ZONAL FLOW...MODELS ARE PRODUCING DIFFERENT SOLUTIONS WITH
TIMING OF WEAK SHORT WAVES PASSING OVER OR NEAR THE GREAT LAKES
REGION FRIDAY INTO SUNDAY. USUALLY THE PACIFIC SYSTEMS ARE ON THE
DRY SIDE BUT WITH H850 TEMPERATURES ABOVE ZERO THIS WEEKEND...PCPN
TYPE ISSUES WILL INCREASE.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 529 PM CST SUN JAN 5 2014
ARCTIC AIR BECOMING ESTABLISHED ACRS THE AREA. EXPECT OCNL MVFR
CIGS AS DEEP VORTEX SLIDES ACRS THE AREA LATE TNGT/EARLY MON.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
WIND CHILL WARNING UNTIL NOON CST TUESDAY FOR WIZ005-010>013-
018>022-030-031-035>040-045-048>050-073-074.
WIND CHILL ADVISORY UNTIL 6 PM CST THIS EVENING FOR WIZ005-
010>012-018-019-030-035-036.
&&
$$
SHORT TERM.....MPC
LONG TERM......TDH
AVIATION.......SKOWRONSKI
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
331 PM CST SAT JAN 4 2014
.TONIGHT AND SUNDAY...FORECAST CONFIDENCE IS HIGH.
WINTER WEATHER ADVISORY FOR WALWORTH...RACINE AND KENOSHA
COUNTIES CONTINUES UNTIL 00Z MONDAY. AREA RADARS SHOWING MORE
BANDS OF LIGHT TO MODERATE SNOW DEVELOPING FROM FAR EASTERN
IOWA...THROUGH NORTHEAST ILLINOIS/FAR SOUTHEAST WISCONSIN...INTO
SOUTHWEST LOWER MICHIGAN.
THIS WAS BEING DRIVEN BY RIGHT ENTRANCE REGION OF 300 MB JET
STREAK...AS WELL AS MODEST LOW TO MID LEVEL FRONTOGENESIS
RESPONSE. THE MID LEVEL FRONTOGENESIS LINGERS ACROSS THE FAR
SOUTHEAST INTO SUNDAY AFTERNOON...WITH 850MB TROUGH/CONVERGENCE
AND LOW LEVEL FRONTOGENESIS RESPONSE ALSO LINGERING INTO TONIGHT.
GOOD UPWARD VERTICAL MOTION SHOWN IN SATURATED AIR COLUMN AND
DENDRITE ZONE ACROSS THE FAR SOUTHEAST COUNTIES THROUGH TONIGHT
AND SUNDAY ON THE NAM. NAM/CANADIAN/ECMWF HAVE QPF LINGERING IN
THE SOUTHEAST THROUGH SUNDAY.
HOWEVER...GFS DRIES OUT LOW AND SOME OF THE MID LEVELS TONIGHT
INTO SUNDAY. THIS RESULTS IN A MAINLY DRY SUNDAY IN THE FAR
SOUTHEAST. HRRR TRYING TO SHOW A PERIOD OF DRY CONDITIONS LATER
THIS EVENING INTO THE OVERNIGHT HOURS BEFORE BRINGING THE SNOW
BACK BY 09Z SUNDAY.
NAM/MESOSCALE MODELS/SOME SREF ENSEMBLES ARE CRANKING OUT QUITE A
BIT OF QPF IN THE FAR SOUTHEAST THROUGH SUNDAY...UP TO AROUND 1/2
INCH IN SOME INSTANCES. FOR NOW...LEANED TOWARD THE WETTER
SOLUTIONS...BUT DID NOT GO QUITE AS HIGH AS THEM WITH QPF AND
SUBSEQUENT SNOW AMOUNTS.
EXPECTING A 3 TO 5 INCH ACCUMULATION NEAR THE BORDER IN KENOSHA
COUNTY THROUGH SUNDAY...TO AROUND AN INCH IN A MILWAUKEE TO BELOIT
LINE...LOWER TO THE NORTH AND WEST. THESE AMOUNTS COULD BE
SOMEWHAT HIGHER IF THE AFOREMENTIONED WETTER LOOKING MODELS
VERIFY...SO INCREASING AMOUNTS AND ADJUSTING HEADLINES ARE
POSSIBLE IN LATER FORECASTS.
STRONG COLD AIR ADVECTION WILL DEVELOP TONIGHT INTO SUNDAY...AS
ARCTIC AIRMASS MOVES INTO THE AREA. WIND CHILLS ARE EXPECTED TO
DROP QUICKLY AWAY IN SOUTH CENTRAL WISCONSIN LATER TONIGHT...AND
ACROSS AREAS AWAY FROM THE LAKE SUNDAY. KEPT WIND CHILL ADVISORIES
GOING FROM PREVIOUS FORECAST. TEMPERATURES WILL DROP QUICKLY
TONIGHT...AND WILL REMAIN NEARLY STEADY SUNDAY WITH COLD AIR
ADVECTION CONTINUING.
.SUNDAY NIGHT THROUGH TUESDAY...FORECAST CONFIDENCE HIGH.
THE FORECAST OF DANGEROUSLY COLD AIR FOR THIS PERIOD REMAINS ON
TRACK. STRONG LOW PRESSURE THAT WILL MOVE UP THE OHIO VALLEY
TONIGHT AND SUNDAY WILL INTENSIFY FURTHER AND LIKELY RETROGRADE A
BIT FARTHER WEST SUNDAY NIGHT INTO MONDAY. THIS MAY ALLOW US TO
ADJUST TEMPS UP A DEGREE OR SO...BUT THE WINDS WILL BE
STRONGER...SO NO NET GAIN ON THOSE BRUTAL WIND CHILL READINGS.
SOME OF THE MODELS SUGGEST THE CHANCE FOR SNOW MAY HANG BACK
ACROSS THE FAR EAST INTO SUNDAY NIGHT DUE TO THE RETROGRADE TRACK
OF THE LOW. I/LL KEEP A VERY SMALL CHANCE IN THE EAST JUST IN
CASE...BUT IT WILL BE MINOR STUFF EITHER WAY.
.WEDNESDAY THROUGH THURSDAY...FORECAST CONFIDNECE IS MEDIUM.
WE START TO SEE A SHIFT TOWARD A WARMER PATTERN BY MID WEEK. TEMPS
TUESDAY NIGHT/WEDNESDAY MORNING WILL STILL BE VERY COLD ABOUT -5
TO -10...COLD BUT A DECENT IMPROVEMENT FROM THE PREVIOUS COUPLE
OF DAYS. A WARM FRONT APPROACHES FROM THE SOUTH AND THIS COUPLED
WITH THE ARRIVAL OF A FAVORABLE ENTRANCE REGION OF AN UPPER JET
SHOULD TRIGGER SOME FRONTOGENESIS AND WARM ADVECTION ACROSS THE
FRONT. ISENTROPICALLY WE START TO SEE SOME DECENT SATURATION AND
ALL THIS COULD RESULT IN SOME LIGHT SNOW WED AND WED NGT WITH ONLY
A SMALL CHANCE LINGERING INTO THURSDAY.
.FRIDAY AND SATURDAY...FORECAST CONFIDENCE IS MEDIUM.
TEMPS ARE EXPECTED TO CLIMB TO NEAR OR SLIGHTLY ABOVE NORMAL BY
THE END OF NEXT WEEK. HIGHS ARE EXPECTED TO CLIMB INTO THE LOWER
TO MID 30S. THIS COMES AS HIGH PRESSURE SLIPS OFF TO THE EAST AND
LOW PRESSURE MOVES ACROSS THE NORTHERN TIER OF THE U.S.
&&
.AVIATION/00Z TAFS/...
EXPECT LIGHT TO MODERATE SNOW TO CONTINUE AT THE EASTERN SITES
TONIGHT AND SUNDAY...WITH MADISON WEST OF THE SNOW.
KENOSHA SHOULD SEE VISIBILITIES DOWN TO AIRFIELD MINIMUMS AT
TIMES FOR MOST OF TONIGHT...AND AROUND OR BELOW ALTERNATE MINIMUMS
LATER TONIGHT AND SUNDAY. SNOWFALL RATES OF 1/4 INCH PER HOUR ARE
EXPECTED TONIGHT...WITH SOME 1/2 INCH PER HOUR RATES POSSIBLE.
TOTAL OF 3 TO 5 INCHES ARE POSSIBLE BY LATE SUNDAY HERE.
MILWAUKEE AND WAUKESHA MAY SEE A BREAK IN THE SNOW THIS EVENING
AND INTO THE OVERNIGHT HOURS...BEFORE IT OCCURS AGAIN LATER
TONIGHT INTO SUNDAY. FOR NOW...KEPT SNOW IN TAFS AS AM DOUBTFUL
THIS WILL OCCUR. RATES WILL BE 1/4 INCH PER HOUR WHEN THE SNOW
FALLS...WITH BRIEF 1/2 INCH PER HOUR RATES POSSIBLE. TOTAL AMOUNTS
OF AROUND AN INCH ARE EXPECTED BY LATE SUNDAY. MADISON SHOULD BE
JUST WEST OF THE SNOW AREA...AND SHOULD NOT SEE ANY ACCUMULATIONS.
SOUTHWEST WINDS WILL SHIFT NORTHWEST EARLY THIS EVENING IN THE
EASTERN SITES...AS COLD FRONT SLIDES SOUTHEAST THROUGH THE AREA.
WINDS WILL BECOME GUSTY BY SUNDAY AFTERNOON. MAY SEE SOME BLOWING
SNOW OCCUR AT THE EASTERN SITES SUNDAY AFTERNOON...BUT
VISIBILITIES SHOULD BE ABOVE 3 MILES.
&&
.MARINE...
SMALL CRAFT ADVISORY HAS BEEN ISSUED FOR SUNDAY...WITH A GALE
WATCH FOR SUNDAY NIGHT THROUGH MONDAY NIGHT...AS A TIGHT PRESSURE
GRADIENT DEVELOPS WITH STRENGTHENING LOW PRESSURE PASSING
SOUTHEAST OF THE REGION. GUSTS MAY REACH GALE FORCE AT TIMES
SUNDAY NIGHT THROUGH MONDAY NIGHT. HIGH WAVES WILL BE LIMITED
TOWARD AND OVER THE OPEN WATERS...IN THE ICE FREE AREAS. GUSTY
WINDS MAY LINGER THROUGH TUESDAY NIGHT...UNTIL STRONG LOW PRESSURE
MOVES AWAY FROM THE REGION.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...WIND CHILL WARNING FROM 6 PM SUNDAY TO NOON CST TUESDAY FOR
WIZ046-047-051-052-056>060-062>072.
WIND CHILL ADVISORY FROM 6 AM TO 6 PM CST SUNDAY FOR WIZ051-058-
063-064-067>069.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CST SUNDAY FOR
WIZ046-047-056-057-062.
WINTER WEATHER ADVISORY UNTIL 6 PM CST SUNDAY FOR WIZ070>072.
LM...GALE WATCH FROM SUNDAY EVENING THROUGH LATE MONDAY NIGHT FOR
LMZ643>646.
SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM CST SUNDAY FOR LMZ643>646.
&&
$$
TONIGHT/SUNDAY AND AVIATION/MARINE...WOOD
SUNDAY NIGHT THROUGH SATURDAY...DAVIS
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 221 PM CST SAT JAN 4 2014
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW AN ARCTIC COLD
FRONT MOVING EAST OVER NORTHEAST WISCONSIN EARLY THIS AFTERNOON.
EARLIER FREEZING DRIZZLE OVER CENTRAL AND NORTH-CENTRAL WISCONSIN
HAS MOSTLY DISSIPATED...AND ONLY A FEW FLURRIES ARE LEFT OVER THE
NORTH. MEANWHILE...CLEARING SKIES ARE WORKING THEIR WAY WEST FROM
MINNESOTA INTO CENTRAL WISCONSIN...BUT WILL TAKE A FEW MORE HOURS
FOR THE NORTH TO CLEAR. FARTHER EAST...SOUTHWEST WINDS IN THE UPPER
LEVELS ARE KEEPING A MID-LEVEL CLOUD DECK OVER THE LOW STRATUS ALONG
THE FRONT. THIS MID-LEVEL CLOUD DECK WILL HANG AROUND INTO THE
EVENING PERIOD. BEHIND THE FRONT...TEMPERATURES ARE GRADUALLY
FALLING BUT THE ARRIVAL OF THE COLDER AIR OVER THE DAKOTAS AND
SOUTHERN CANADA WITHIN SURFACE HIGH PRESSURE LOOKS DELAYED
SOMEWHAT. THE COLDEST AIR...HOWEVER...STILL RESIDES OVER NORTHERN
SASKATCHEWAN AND IS POISED TO ARRIVE LATE TOMORROW AFTERNOON.
TEMPERATURES AND WIND CHILL VALUES ARE THE MAIN FORECAST CONCERNS IN
THE SHORT TERM AS ARCTIC AIR RETURNS.
TONIGHT...THE ARCTIC FRONT WILL SHIFT EAST ACROSS CENTRAL AND
SOUTHERN GREAT LAKES WHERE A BAND OF SNOW WILL OCCUR. NORTHWEST OF THE
FRONT...ARCTIC HIGH PRESSURE WILL BE BUILDING SOUTHEAST INTO THE
REGION...AND PUSHING IN INCREASING AMOUNTS OF DRIER AIR IN THE LOW
LEVELS. THIS DRY AIR SHOULD HELP ERODE MUCH OF THE LOW CLOUD COVER
BY THE START OF THE EVENING. WITH WINDS A LITTLE TOO WESTERLY FOR
MUCH OF A LAKE EFFECT COMPONENT ACROSS THE SNOW BELTS...THE ONLY
CLOUD COVER WILL BE A BAND OF MID AND HIGH CLOUDS AS UPPER LEVEL
FLOW WILL REMAIN OUT OF THE SOUTHWEST WHICH WILL KEEP SKIES PARTLY
TO MOSTLY CLOUDY. IN REGARDS TO TEMPERATURES...WNW WINDS WILL BE
COLD ADVECTING THROUGH THE NIGHT WITH 850MB TEMPS DROPPING TO 23
BELOW OVER N-C WISCONSIN. TEMPS LAST NIGHT OVER NORTHERN MINNESOTA
WERE ONLY IN THE SINGLE DIGITS ABOVE AND BELOW ZERO...SO AM
CONCERNED ABOUT DROPPING TEMPS TOO MUCH. NOT CONFIDENT OF
DECOUPLING OCCURRING...SO WILL GO WITH LOWS AROUND IN THE NEG TEENS
BELOW ZERO OVER CENTRAL AND NORTH-CENTRAL WISCONSIN TO THE SINGLE
DIGITS ABOVE ZERO ALONG THE LAKE SHORE. AS MENTIONED ABOVE...THE
BITTERLY COLD AIR LOOKS TO BE DELAYED BY A FEW HOURS...AND MAY NOT REACH
WIND CHILL ADVISORY CRITERIA UNTIL 03Z OVER THE WESTERN FORECAST
AREA. WITH COORD FROM FORECAST OFFICES TO THE WEST...WILL DELAY THE
START TIME OF THE WESTERN ADVISORY UNTIL 03Z. THE EAST WILL START
AT 06Z AS PLANNED.
SUNDAY...SKIES WILL CONTINUE TO BE PARTLY TO MOSTLY CLOUDY WITH MID
HIGH CLOUDS OVERHEAD. SHOULD SEE THESE CLOUDS DEPART TO THE
SOUTHEAST BY LATE MORNING OR EARLY AFTERNOON. THEN A LOBE OF THE
POLAR VORTEX WILL SWING SOUTHEAST INTO THE NORTHERN MISSISSIPPI
VALLEY DURING THE AFTERNOON. A SECONDARY SURGE OF ARCTIC AIR WILL
ARRIVE WITH THE POLAR VORTEX...AND TEMPS MAY START THEIR FALL BY
MID-AFTERNOON. OFTEN WITH THE LEADING EDGE OF THESE BITTERLY COLD
AIRMASSES THERE ARE SCT INSTABILITY SNOW SHOWERS AND MODELS ARE
SHOWING HIGHER LOW LEVEL MOISTURE INCOMING TOMORROW AFTERNOON. NOT
SURE IF THIS WILL OCCUR IN THIS CASE SINCE THERE IS NO DEFINED
ARCTIC FRONT...BUT DID SHOW INCREASING CLOUDS LATE IN THE
AFTERNOON. ANOTHER THING TO KEEP TABS ON IS THE NORTHERN EXTENT OF
THE PRECIP TOMORROW AFTERNOON WITH WITH THE CYCLONE MOVING OVER THE
OHIO VALLEY. BOTH THE NAM AND GEM BRING LIGHT PRECIP INTO FAR E-C
WISCONSIN IN THE AFTERNOON...BUT THIS LOOKS TOO FAR INTO THE ARCTIC
AIRMASS. WILL LEAVE POPS OUT. WITH THE FALLING TEMPS IN THE
AFTERNOON...WIND CHILLS WILL BE APPROACHING WARNING CRITERIA OVER
CENTRAL AND NORTH-CENTRAL WISCONSIN BY 00Z MON.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 221 PM CST SAT JAN 4 2014
PROGS STILL PASS THE CORE OF THE POLAR VORTEX OVER THE REGION
SUNDAY NIGHT INTO MONDAY BEFORE LIFTING EASTWARD INTO TUESDAY.
STRONG BAROCLINIC ZONE IN THE LEAD ARCTIC SURFACE FRONT POSITIONED
TO THE SOUTH AND EAST OF THE AREA LATE SUNDAY WILL BE THE FOCUS OF
ANOTHER SURFACE WAVE AND A REGION OF SNOW EARLY SUNDAY EVENING.
WHILE THE GFS KEEPS THIS AREA OF SNOW SOUTH OF THE AREA SUNDAY
EVENING...THE NAM LIFTS THE NORTHERN PERIPHERY OF THIS SNOW INTO
PARTS OF EAST CENTRAL WISCONSIN. FOR THIS SCENARIO TEMPS WOULD BE
A FEW DEGREES WARMER...BUT WINDS WOULD BE STRONGER DUE TO THE
LOCATION OF THE SURFACE WAVE AND PRESSURE GRADIENT. REGARDLESS OF
EITHER SCENARIO...LITTLE CHANGE TO GOING EXTREME COLD WIND CHILL
FORECASTS...SO NO CHANGES TO THE GOING WIND CHILL WARNING
HEADLINES STARTING SUNDAY EVENING.
FOR THE REST OF THE MODELS CONCERNING THIS LIGHT SNOW POTENTIAL
SUNDAY EVENING FOR THE LAKESHORE REGION...THE GEM AND ECMWF ALSO
PRODUCE SOME LIGHT SNOW ALONG THE LAKE SHORE REGION IN THE EVENING
HOURS. PERHAPS THE MODELS ARE PICKING UP A TREND OF A CONVERGENT
REGION DEVELOPING ON THE WEST SIDE OF LAKE MICHIGAN DUE TO THE
STRONGER WINDS ON THE LAKE PULLING AWAY FROM THE AREA. SURFACE
PRESSURE PLOTS SUGGEST A SUBTLE HEIGHT FALL OVER LAKE MICHIGAN AS
WELL. INCREASING UNSTABLE CONDITIONS OVER THE LAKE ALSO DEVELOPING
WITH THE POLAR VORTEX AND BAROCLINIC ZONE APPROACHING. WILL ADD A
SMALL CHANCE FOR SNOW SHOWERS FOR NOW..BUT ITS POSSIBLE THIS MAY
NEED TO BE INCREASED A LITTLE.
UPPER PATTERN GRADUALLY TURNS MORE ZONAL MID WEEK FOR A TURN TO
MORE NORMAL CONDITIONS. A PIECE OF SOUTHERN STREAM ENERGY SLIDES
OVER THE MID MISSISSIPPI VALLEY REGION WEDNESDAY NIGHT INTO
THURSDAY AND ALONG THE H850 FRONTAL BOUNDARY...GLANCING THE SOUTH
HALF OF THE FORECAST REGION WITH LIGHT SNOW. ANOTHER SHORT WAVE
TROUGH MAY SLIDE OVER THE GREAT LAKES REGION FRIDAY NIGHT INTO
SATURDAY FOR ANOTHER CHANCE OF SNOW OR SNOW MIX...OTHERWISE THE
DRIER WESTERLY OR PACIFIC FLOW CONTINUES INTO THE WEEKEND WITH
MODERATING DAY TIME HIGH TEMPERATURES APPROACHING THE LOWER 30S
WITH NO MAJOR WEATHER SYSTEMS NOTED AT THIS TIME.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1118 AM CST SAT JAN 4 2014
BEHIND AN ARCTIC FRONT...WHICH IS MOVING ACROSS CENTRAL AND
NORTHEAST WISCONSIN AT MIDDAY...AREAS OF FREEZING DRIZZLE ARE BECOMING
MORE PATCHY OVER CENTRAL AND NORTH-CENTRAL WISCONSIN. HAVE ENDED
THE FREEZING DRIZZLE MENTION AT THE START OF THE 18Z TAFS...BUT
WILL HAVE TO MONITOR IN CASE NEED TO THROW IN A 1 HR TEMPO GROUP
IF IT CONTINUES LONGER THAN EXPECTED. IN GENERAL...CIGS AND VSBYS
HAVE BEEN TRENDING UPWARD INTO THE MVFR RANGE OVER THE PAST HOUR
AND THIS TREND SHOULD CONTINUE THROUGH THE AFTERNOON AS DRY ARCTIC
AIR FILTERS IN BEHIND THE FRONT. NOT THINKING ANY FREEZING DRIZZLE
WILL MAKE IT INTO THE FOX VALLEY OR NE WISCONSIN THIS AFTERNOON.
OTHERWISE...ANTICIPATE CONDITIONS TO IMPROVE THROUGH THE AFTERNOON
TO VFR BY EARLY THIS EVENING ACROSS THE REGION. VFR CONDITIONS
WILL THEN REMAIN THROUGH THE END OF THE TAF PERIOD WITH ONLY A
BKN-OVC MID AND HIGH DECK OVERHEAD.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
WIND CHILL WARNING FROM 6 PM SUNDAY TO NOON CST TUESDAY FOR
WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CST SUNDAY FOR
WIZ013-020-021-031-037>039-045-048-049-073-074.
WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO 6 PM CST SUNDAY
FOR WIZ005-010>012-018-019-030-035-036.
&&
$$
SHORT TERM.....MPC
LONG TERM......TDH
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
439 AM EST MON JAN 6 2014
.SYNOPSIS...
A POTENT COLD FRONT WILL CROSS THE REGION THIS MORNING. ARCTIC
HIGH PRESSURE WILL THEN BUILD IN WAKE OF THE FRONT AND LINGER
THROUGH THE MIDDLE OF THE WEEK. A COASTAL TROUGH WILL THEN DEVELOP
OFFSHORE LATE WEEK BEFORE ANOTHER COLD FRONT APPROACHES THE AREA LATE
WEEKEND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
PRE-DAWN...IT HAS BEEN A BUSY OVERNIGHT DEALING WITH THE EXTREMELY
TRANSIENT SEA FOG BRUSHING COASTAL ZONES AND MARINE WATERS AND THE
STRONG LOW LEVEL WARM AIR ADVECTION PATTERN AHEAD OF THE POWERHOUSE
ARCTIC COLD FRONT BLASTING THROUGH CENTRAL GEORGIA AND THE MOUNTAIN
CHAIN. LOW LEVEL WIND FIELDS ARE VEERING AND INCREASING STEADILY
WITH TIME AND VSBY ISSUES IMPROVING ALONG THE COAST. WE THINK BY
5 AM WE WILL BE LOWERING ALL FOG BASED ADVISORIES BASED ON VERY
RECENT TRENDS. TEMPS HAVE WARMED TO THE MID 60S ALONG THE COAST
AND WINDS WERE STARTING TO GUST...OBVIOUSLY THE HIGHS TEMPS FOR
TODAY OCCURRING NOW. THE FRONT JUST BLASTED THROUGH MACON GEORGIA
WITH GUSTS TO 35 KT...A HARBINGER OF THINGS TO COME FOR OUR AREA.
THE STRONG COLD FRONT WILL SWEEP THROUGH THE AREA THIS MORNING
WITH ARCTIC HIGH PRESSURE BEGINNING TO USHER IN BEHIND. PRECIP
POTENTIAL WITH THE FRONTAL PASSAGE LOOKS RATHER LOW GIVEN THE FACT
THAT MODEL TIME SECTIONS SHOW THE MOISTURE SCOURING OUT BY SHORTLY
AFTER DAYBREAK. THERE WILL PROBABLY BE A POCKETS OF LIGHT RAIN
SHOWERS ACCOMPANYING THE FRONT...MOVING OFF THE COAST BY MID TO
LATE MORNING. WE HAVE 20-30 PERCENT POPS DROPPING OFF BY NOON.
CLEARING EXPECTED INLAND DURING THE AFTERNOON AS MUCH DRIER AIR
FILTERS IN. THE INTENSE UPPER JET SEGMENT CLOSE TO 200 KT AT 250
MB MOVING INTO GEORGIA AND THE UPSTATE CAROLINAS SHOULD PRODUCE
BAND OF HIGH CLOUDS THIS AFTERNOON AND EVENING...A BIT UNCERTAIN
OF THEIR OPACITY AT THIS TIME.
WINDY CONDITIONS DEVELOP BY MID MORNING IN THE WAKE OF THE FRONT.
LOW-LEVEL WINDS WILL RAPIDLY INCREASE WITH WIND SPEEDS ATOP THE
MIXED LAYER INCREASING TO 35 KT BY LATE AFTERNOON. THE GUSTY WNW
WINDS COMBINED WITH STRONG COLD ADVECTION HAVE PROMPTED THE
ISSUANCE OF A WIND ADVISORY FOR SE GEORGIA AND EXTREME SOUTHERN
SOUTH CAROLINA BORDERING THE SAVANNAH RIVER. RECENT RAP MODEL
OUTPUT INDICATE A NOSE OF ENHANCED 1000 MB GEOSTROPHIC FLOW ARCING
INTO OUR SOUTHERN ZONES LIKE A BLADE TODAY. STRONG DOWNHILL
MOMENTUM...RAPIDLY DRYING AND SINKING AIR POST FRONTAL WERE ENOUGH
OF A CONCERN TO ISSUE THE ADVISORY FOR PERIODS OF STRONG WIND
GUSTS AT OR SLIGHTLY ABOVE 40 MPH. IN THE CHARLESTON TRI-COUNTY
AREA THE GUSTS NOT QUITE AS STRONG AS SAVANNAH GIVEN THE OFFSHORE
PUSH AROUND THE SOUTHERN END OF THE MOUNTAINS SO WE HELD OFF.
TODAY/S SHIFT WILL MONITOR TRENDS FOR ANY POSSIBLE EXTENSION IN
EITHER SPACE OR TIME.
STRONG COLD ADVECTION CONTINUES INTO TONIGHT WITH A DOWN-RIGHT COLD
AIRMASS SETTLING OVER THE AREA. LOW TEMPS WILL BE IN THE MID TEENS
FAR INLAND WITH UPPER TEENS TO LOWER 20S ALL THE WAY TO THE COAST.
ALTHOUGH LOW-LEVEL WINDS DROP OFF CONSIDERABLY AFTER MIDNIGHT...
BREEZY WINDS PERSIST DUE TO THE STRONG COLD ADVECTION. WE ARE IN
LINE WITH NEIGHBORING OFFICES WITH THE ISSUANCE OF A WIND CHILL
ADVISORY FOR LATE TONIGHT INTO MID TUESDAY MORNING. IT IS STILL
POSSIBLE THAT OUR WIND CHILL FORECAST MAY BE JUST A TAD LOW GIVEN
UNCERTAINTIES OF ACTUAL WIND SPEEDS DURING THE HOURS AROUND
DAYBREAK TUESDAY. HOWEVER GIVEN THE ANOMALOUS AIR MASS...IMPACTS WITH
WIND/COLD OF THIS NATURE WERE TAKEN SERIOUSLY FOR THOSE EXPOSED TO
THESE ELEMENTS. WE WILL REISSUE A PNS ON THE COLD WEATHER EARLY
THIS MORNING.
LAKE WINDS...DANGEROUS BOATING CONDITIONS WILL LIKELY DEVELOP IN
THE WAKE OF STRONG COLD FRONT LATER TODAY AND ESPECIALLY AFTER
SUNSET INTO THE EVENING HOURS.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
TUESDAY...A WIND CHILL ADVISORY WILL LIKELY BE ONGOING FOR ALL
AREAS THROUGH LATE MORNING WITH ZERO TO 5 DEGREE WIND CHILL VALUES
EVEN UP ALONG THE COAST AS A WEST/NORTHWEST WIND CONTINUES. WINDS
WILL THEN BEGIN TO RELAX WHILE TEMPS GRADUALLY WARM...PUTTING AN
END TO A WIND CHILL ADVISORY BY 11 AM. DESPITE AN IMPROVEMENT TO
TEMPS AND WINDS...ARCTIC HIGH PRESSURE WILL CONTINUE TO BUILD FROM
THE WEST AND NORTHWEST...BECOMING CENTERED OVER OR JUST NORTH OF
THE AREA BY TUESDAY NIGHT. THE PATTERN WILL FAVOR ONGOING STRONG
COLD AIR ADVECTION OVER SOUTHEAST SOUTH CAROLINA AND SOUTHEAST
GEORGIA THROUGHOUT THE DAY WHILE THE AREA REMAINS ALONG THE
SOUTHERN PERIPHERY OF A LARGE MID LVL TROUGH SHIFTING OFF THE
EASTERN SEABOARD. AS A RESULT...HIGH TEMPS ON TUESDAY WILL BE SOME
OF THE COLDEST WE HAVE SEEN SO FAR THIS YEAR. EXPECT TEMPS TO PEAK
ONLY IN THE LOW/MID 30S INLAND TO MID/UPPER 30S ALONG THE COAST.
WEATHER CONDITIONS WILL REMAIN DRY WITH THE ARCTIC AIRMASS IN
PLACE.
OVERNIGHT LOWS WILL BE VERY COLD ONCE AGAIN...MAINLY DUE TO THE
POSITION OF THE ARCTIC HIGH AND STRONG RADIATIONAL COOLING UNDER
LIGHT/CALM WINDS. EXPECT LOW TEMPS IN THE MID/UPPER TEENS INLAND AND
MID/UPPER 20S ALONG THE COAST. WIND CHILL TEMPERATURES MAY REACH AS
LOW AS 15 TO 20 DEGREES.
WEDNESDAY AND THURSDAY...CONDITIONS WILL REMAIN DRY ON WEDNESDAY AS
THE CENTER OF VERY COLD/DRY HIGH PRESSURE SLOWLY SHIFTS OFF THE MID
ATLANTIC COAST. A COASTAL TROUGH WILL THEN BEGIN TO DEVELOP OFFSHORE
ALONG THE SOUTHERN EDGE OF THE SFC HIGH WEDNESDAY NIGHT AND
THURSDAY. THE PATTERN WILL RESULT IN A GRADUAL MODIFICATION OF TEMPS
AS MID LVL RIDGING OCCURS OVER THE SOUTHEASTERN UNITED STATES WHILE
SFC WINDS SHIFT FROM NORTHWEST TO NORTHEAST. HOWEVER...TEMPS MAY
STRUGGLE TO WARM SIGNIFICANTLY OVER INLAND AREAS WHERE SFC HIGH
PRESSURE EXTENDS SOUTHWEST FROM THE CENTER OF THE ARCTIC HIGH OFF THE
MID ATLANTIC COAST. AS A RESULT...WARMEST TEMPS SHOULD OCCUR NEAR
THE COAST IN SOUTHEAST SOUTH CAROLINA AND SOUTHEAST GEORGIA WHERE
ONSHORE FLOW DEVELOPS. EXPECT OVERALL HIGHS IN THE MID/UPPER 40S ON
WEDNESDAY...WITH OVERNIGHT LOWS IN THE LOW 30S INLAND TO UPPER
30S/LOWER 40S ALONG THE COAST. TEMPS SHOULD THEN WARM INTO THE
MID/UPPER 50S INLAND TO LOWER 60S ALONG THE COAST ON THURSDAY.
CHANCES OF PRECIP SHOULD ALSO INCREASE WITH ISENTROPIC ASCENT AND
THE STRENGTHENING OF THE COASTAL TROUGH JUST OFFSHORE ON THURSDAY.
HOWEVER...PRECIP ACTIVITY COULD HAVE A TOUGH TIME MAKING IT WELL
INLAND WHERE HIGH PRESSURE LINGERS. HAVE THEREFORE MAINTAINED SLIGHT
CHANCE POPS IN THE FORECAST AT THIS TIME.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
A COASTAL TROUGH WILL CONTINUE TO STRENGTHEN ALONG THE SOUTHERN
PERIPHERY OF HIGH PRESSURE OFF THE MID ATLANTIC COAST THROUGH LATE
WEEK. THIS FEATURE ALONG WITH ISENTROPIC LIFT SHOULD SUPPORT A FEW
SHOWERS OVER THE AREA ON FRIDAY...BEFORE COVERAGE INCREASES ON
SATURDAY AS THE COASTAL TROUGH LIFTS NORTH WITH A WARMER AIR MASS
WELL AHEAD OF A COLD FRONT/SFC LOW APPROACHING FROM THE WEST. FORECAST
CONFIDENCE REMAINS VERY LOW WITH REGARDS TO THE TIMING AND STRENGTH
OF THE COLD FRONT/SFC LOW APPROACHING THE SOUTHEASTERN UNITED
STATES...BUT THE GENERAL CONSENSUS IS THAT TEMPS WILL WARM
CONSIDERABLY AND CHANCES OF PRECIP WILL INCREASE UNTIL THE FEATURE
SHIFTS OFFSHORE EARLY NEXT WEEK. HAVE THEREFORE MAINTAINED A 30-40
POP SCHEME SUNDAY...BEFORE GRADUALLY LOWERING POPS ON MONDAY.
OVERALL...HIGH TEMPS SHOULD REACH THE LOWER 60S ON FRIDAY...THEN
MID/UPPER 60S ON SATURDAY AND SUNDAY...BEFORE SLIGHTLY COOLING INTO
THE LOW/MID 60S ON MONDAY. OVERNIGHT LOWS SHOULD ALSO SHOW A WARMING
TREND INTO EARLY NEXT WEEK...WITH TEMPS STARTING IN THE UPPER 30S TO
MIDDLE 40S THURSDAY NIGHT...THEN UPPER 40S TO MIDDLE 50S THIS
WEEKEND AND EARLY NEXT WEEK.
&&
.AVIATION /09Z MONDAY THROUGH FRIDAY/...
TAFS AMENDED FOR HIGHER-END IFR CIGS AND INCREASING SW FLOW UNTIL
THE FRONTAL PASSAGE. STRONG GUSTY SURFACE WINDS WILL USHER IN AN
VERY COLD AIR MASS TODAY AND TONIGHT WITH VFR CONDITIONS AFTER THE
SHIFT TO WEST NORTHWEST WIND DIRECTIONS. FREQUENT GUSTS 25-30 KT
ARE LIKELY THROUGH THIS EVENING WITH SOME GUSTS UP TO 35 KT
POSSIBLE AT SOME POINT DURING THE STRONGEST PRES RISES LATER THIS
MORNING INTO THIS AFTERNOON.
EXTENDED AVIATION OUTLOOK...GUSTY WINDS ARE POSSIBLE AT BOTH
TERMINALS EARLY TUESDAY. OTHERWISE...VFR CONDITIONS SHOULD PREVAIL
TUESDAY INTO THURSDAY. ANOTHER ROUND OF MVFR CIGS/VSBYS IS POSSIBLE
FRIDAY AND SATURDAY AS A COASTAL TROUGH LIFTS NORTH OVER THE AREA.
&&
.MARINE...
A SIGNIFICANT MARINE EVENT WILL UNFOLD TODAY AND TONIGHT ACROSS
ALL OF THE WATERS BEHIND A STRONG COLD FRONT. 35-40 KT BOUNDARY
LAYER WINDS COMBINED WITH VERY STRONG COLD ADVECTION MOVING OVER
THE WARMER ATLANTIC WATERS WILL RESULT IN GALE CONDITIONS
BEGINNING THIS MORNING SOUTH OF CHARLESTON AND CONTINUING THROUGH
MUCH OF TONIGHT. THE STRONGEST SURGE IN SURFACE WINDS WILL LIKELY
BE THIS EVENING INTO THE FIRST PART OF THE OVERNIGHT AS -6C TO -12C
TEMPS AT H925 PLOW OVER THE WATERS. THERE IS A LOT OF MESOSCALE
INFLUENCES AND NUANCES INVOLVED WITH A COASTAL WATERS FORECAST LIKE
THIS AND WE BEGIN TO TRY TO SHOW SOME OF THE DETAILS IN THE GRIDS
THIS MORNING. THE OVERALL BOTTOM LINE TO ANYONE WITH MARINE INTEREST
IS PREPARE FOR EXTREMELY NASTY CONDITIONS WITH THE ADDED CONCERN
OF WIND CHILLS IN THE 10-20 DEGREE RANGE.
TUESDAY THROUGH FRIDAY...SMALL CRAFT ADVISORIES WILL LIKELY BE
ONGOING FOR ALL WATERS EARLY TUESDAY BEFORE WINDS/SEAS STEADILY
IMPROVE AS STRONGER LOW LVL WINDS SHIFT NORTHEAST AND AWAY FROM THE
AREA BY TUESDAY AFTERNOON. AS A RESULT...SMALL CRAFT ADVISORIES
WILL LIKELY NOT BE NEEDED BY TUESDAY AFTERNOON FOR NEARSHORE WATERS
AND BY TUESDAY EVENING FOR OFFSHORE GEORGIA WATERS. WINDS/SEAS
COULD APPROACH SMALL CRAFT ADVISORY LEVELS OVER OUTER GEORGIA WATERS
WEDNESDAY NIGHT INTO THURSDAY AS A COASTAL TROUGH DEVELOPS
OFFSHORE...WITH WINDS GUSTING UP TO 20-25 KT AND SEAS BUILDING UP TO
6 FT. CONDITIONS SHOULD THEN REMAIN BELOW SMALL CRAFT ADVISORY
LEVELS INTO EARLY WEEKEND AS THE COASTAL TROUGH BEGINS TO LIFT NORTH
WITH A FEW SHOWERS OVER THE WATERS.
&&
.TIDES/COASTAL FLOODING...
ANOTHER ROUND OF BLOW-OUT TIDES ARE LIKELY ON LOW TIDES MONDAY INTO
TUESDAY WITH THE PASSAGE OF AN ARCTIC COLD FRONT. STRONG OFFSHORE
FLOW AROUND LOW TIDE COULD RESULT IN VERY LOW WATER LEVELS. THE LOW
TIDE AROUND DAYBREAK ON TUESDAY LOOKS THE MOST SIGNIFICANT.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...WIND ADVISORY FROM 10 AM THIS MORNING TO 7 PM EST THIS EVENING
FOR GAZ087-088-099>101-114>119-137>141.
WIND CHILL ADVISORY FROM 1 AM TO 10 AM EST TUESDAY FOR GAZ087-
088-099>101-114>119-137>141.
DENSE FOG ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
GAZ117-119-139-141.
SC...WIND ADVISORY FROM 10 AM THIS MORNING TO 7 PM EST THIS EVENING
FOR SCZ040-042-047-048-051.
WIND CHILL ADVISORY FROM 1 AM TO 10 AM EST TUESDAY FOR SCZ040-
042>045-047>052.
DENSE FOG ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
SCZ048>051.
LAKE WIND ADVISORY UNTIL NOON EST TUESDAY FOR SCZ045.
MARINE...DENSE FOG ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
AMZ330-350-352-354.
GALE WARNING UNTIL 4 AM EST TUESDAY FOR AMZ330-350-352-354.
GALE WARNING UNTIL 6 AM EST TUESDAY FOR AMZ374.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...DPB
LONG TERM...DPB
AVIATION...
MARINE...DPB
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1140 PM EST SUN JAN 5 2014
.SYNOPSIS...
ISSUED AT 520 AM EST SUN JAN 5 2014
A STRONG SYSTEM WILL BRING HEAVY SNOW TO THE AREA TODAY AND INTO
THIS EVENING. AMOUNTS OF 8 TO 16 INCHES ARE POSSIBLE. A WINTER
STORM WARNING IS IN EFFECT THROUGH THIS EVENING. EXTREMELY COLD
ARCTIC AIR WILL MOVE IN BEHIND THE SYSTEM THROUGH EARLY NEXT WEEK
WITH WIND CHILLS OF AROUND 40 BELOW ZERO SUNDAY NIGHT INTO
TUESDAY. A WIND CHILL WARNING IS IN EFFECT FOR THIS PERIOD. LOW
TEMPERATURES TONIGHT WILL CRASH TO BETWEEN 5 BELOW ZERO AND 18
BELOW ZERO BY DAYBREAK MONDAY.
&&
.UPDATE...
ISSUED AT 810 PM EST SUN JAN 5 2014
UPSTREAM OBSERVATIONAL TRENDS WITHIN LL CAA WING AND ALG NRN
EXTENT OF INTENSE SFC RISE/FALL PRES COUPLET AND NR TERM RUC
GUIDANCE SPURNED EARLIER BLIZZARD UPGRADE OVR WRN AREAS. JUST NOW
SEEING SFC GUSTS OVR 30KTS IN WHITE COUNTY AND XPC THIS TO SPREAD
EWD THROUGH THIS EVENING. RUC PROGS CARRY 40KT SFC WIND MAX UP TO
THE SR 36 CORRIDOR BY 03Z...SR 331 BY 05Z AND SR 15 BY 06Z AND
LASTING FOR ABOUT 6 HOURS BFR ABATING.
THIS MAY AFFECT ERN AREAS AS WELL BUT WILL WATCH TRENDS ACRS WRN
HALF THIS EVENING. HWVR ITS LIKELY THAT AFT SUNRISE...LOCATIONS
SOUTH OF LK SHSN OVR NE IN/NW OH WILL MIX SIGLY AND YIELD CONTD
SIG BLOWING/DRIFTING.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 350 PM EST SUN JAN 5 2014
HEIGHT OF HISTORIC WINTER STORM NOW WELL UNDERWAY ACROSS THE REGION
AT PRESS TIME. CULMINATION OF FACTORS SUPPORTING WIDESPREAD
ACCUMULATIONS OF 10-16 INCHES. COUPLED UPPER LEVEL JET STREAKS
FAVORING EFFECTIVE DIVERGENCE ALOFT WITH SOUTHERN BRANCH
STRENGTHENING TO 170+ KTS OVERNIGHT AND SHOWING A GREAT DEAL OF
CYCLONIC CURVATURE. LOW TO MIDLEVEL FGEN/DEFORMATION RESPONSE IS
SUPERB AND THE TRACK OF THE SURFACE LOW IS NEARLY IDEAL FOR A LONG
DURATION OF HEAVY SNOW IN OUR CWA. WATER VAPOR LOOP SHOWS POLAR
VORTEX PHASING WITH POTENT SOUTHERN STREAM PV ANOMALY AND RAPIDLY
BECOMING NEGATIVELY TILTED. THIS IS NOT ONLY SUPPORTING RAPID
DEEPENING OF THE SURFACE CYCLONE BUT ALSO PULLING IT A BIT TO THE
LEFT AS PREVIOUSLY DISCUSSED. THIS HAS ALLOWED SURFACE TEMPERATURES
TO CLIMB TO AROUND 32F AND WITH WARMER PROFILES ALOFT...CAUSED SNOW
RATIOS TO BE ONLY AROUND 10:1 FOR OUR CENTRAL AND SOUTHEAST
COUNTIES. THIS HAS BEEN ONE POTENTIAL LIMITING FACTOR BUT HAS BEEN
MORE THAN MADE UP FOR WITH IMPRESSIVE QPF TOTALS. MOISTURE
CONVERGENCE IS EXCELLENT WITH 280K MIXING RATIOS APPROACHING 4 G/KG.
ELEVATED INSTABILITY ABOVE ROUGHLY 600MB IS ALSO AIDING HIGHLY
EFFICIENT UVM AND BANDS OF HEAVY SNOWFALL ARE CLEARLY EVIDENT ON
RADAR. SNOWFALL RATES HAVE EXCEEDED 2"/HR IN THESE BANDS. EXPECT
STATUS QUO TO CONTINUE FOR ANOTHER 4-6 HOURS AND WITH ACCUMULATIONS
ALREADY EXCEEDING 8 INCHES IN SOME SPOTS...A FEW STORM TOTALS IN
EXCESS OF 16 INCHES MAY BE POSSIBLE BY LATER TONIGHT. CYCLONE WILL
LIFT RAPIDLY NORTHEAST BY 03Z THOUGH AND EXPECT MOST OF THE SYNOPTIC
SNOW TO WIND DOWN SHORTLY THEREAFTER.
ONE OF THE BIGGEST QUESTIONS REGARDING THIS STORM HAS BEEN THE
POTENTIAL FOR BLIZZARD CONDITIONS. EXPLOSIVE CYCLOGENESIS NOW
UNDERWAY WILL LEAD TO A VERY STRONG ISALLOBARIC COMPONENT TO THE
WIND BY LATER THIS EVENING. COUPLED WITH A TIGHT GRADIENT AND
RELATIVELY DEEP MIXING HEIGHTS...THIS WILL LEAD TO A BRIEF PERIOD OF
30-35 MPH GUSTS WHILE NEW SNOW IS STILL FALLING THIS EVENING. THIS
WILL LEAD TO NEAR BLIZZARD CONDITIONS WITH WIDESPREAD BLOWING AND
DRIFTING SNOW. VISIBILITY REQUIREMENT OF LESS THAN A QUARTER MILE
FOR THREE CONSECUTIVE HOURS IS EXTREMELY TOUGH TO GET IN THIS PART
OF THE COUNTRY THOUGH AND ONLY ONE UPSTREAM STATION (KCMI) HAS
REPORTED SUCH A LOW VISIBILITY. AFTER FURTHER COLLABORATION WITH
NEIGHBORING OFFICES...DECIDED TO HOLD OFF ON A BLIZZARD WARNING
UNLESS NEW OBSERVATIONAL EVIDENCE SUGGESTS OTHERWISE THIS EVENING.
SIGNIFICANT IMPACTS WILL CONTINUE THROUGH THE OVERNIGHT AND INTO
TOMORROW. MODEST LAKE RESPONSE EXPECTED GIVEN STRONG INSTABILITY AND
LINGERING SYNOPTIC MOISTURE. WINDS WILL QUICKLY BACK TO A WESTERLY
DIRECTION THIS EVENING AND THE BULK OF THE ADDITIONAL ACCUMULATION
OVERNIGHT AND INTO TOMORROW WILL BE MAINLY CONFINED NORTH OF THE
TOLL ROAD. INCREASING DRY AIR ADVECTION AND LOW SNOW RATIOS WILL
LIMIT ADDITIONAL ACCUMULATIONS TO AROUND 2-4 INCHES. BIGGEST HAZARD
WILL BE THE DANGEROUSLY COLD TEMPERATURES/WIND CHILLS. STILL
EXPECTING LOWS TO PLUMMET INTO THE MID TEENS BELOW ZERO BY LATE
TONIGHT WITH NO DIURNAL RECOVERY TOMORROW IN THE FACE OF STRONG CAA.
WIND SPEEDS OF 20-30 MPH WILL GENERATE WIND CHILL TEMPERATURES OF
AROUND -40F. NO CHANGES TO WIND CHILL WARNING NECESSARY.
&&
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 350 PM EST SUN JAN 5 2014
HISTORIC/POTENTIALLY LIFE-THREATENING COLD WILL GIVE WAY TO
SIGNIFICANT WARMING BY END OF THE WEEK. ONLY MINOR CHANGES MADE
GIVEN ONGOING WINTER STORM.
PERIOD WILL START WITH THE MUCH ADVERTISED CORE OF ARCTIC AIR
OVERHEAD AS LOWS STILL ON TARGET TO DROP TO 15 TO 20 BELOW WITH WIND
CHILLS OF 30 TO 45 BELOW INTO MID MORNING TUESDAY. IN ADDITION
EXTREME INSTABILITY WILL BE ONGOING OVER THE LAKE AS DELTA T`S ALL
THE WAY TO 700 MB TOP OUT AROUND 30 C WITH INVERSION HGTS AROUND
8000 FT. LIGHT TO MODERATE SNOW SHOULD BE OCCURRING BUT GENERAL
WESTERLY FLOW WILL KEEP MOST SNOW CONFINED TO FAR SOUTHERN LOWER
MICHIGAN. HAVE INCREASED POPS INTO CAT RANGE ACROSS N BERRIEN COUNTY
IN MOST FAVORABLE AREA AND NUDGED UP ACCUMS A TOUCH. ONE MORE BITTER
COLD DAY IN STORE FOR TUESDAY ALTHOUGH SOME AREAS WILL BE A GOOD 5
TO 10 DEGREES WARMER THAN MONDAY. NEVERTHELESS..ONLY LOCATIONS
ALONG THE LAKE WILL SEE TEMPS CLIMB ABOVE ZERO. WINDS WILL STILL BE
IN THE 10 TO 20 MPH RANGE WILL RESULT IN WIDESPREAD DRIFTING...BUT
ACTUAL BLOWING SNOW/REDUCED VSBYS WILL PROBABLY BE ISOLATED. FOR NOW
WILL LEAVE OUT OF GRIDS FOR BOTH MONDAY NIGHT AND TUESDAY.
CENTER OF POLAR VORTEX WILL RETREAT NORTH TO EAST OF HUDSON BAY
ALLOWING HGTS TO INCREASE AND THE START OF A WARMUP WHICH LOOKS TO
LAST THROUGH THE LONG TERM PERIOD. THIS WILL BRING CHALLENGES OF ITS
OWN AS ACTIVE FLOW CONTINUES WITH SEVERAL WAVES MOVING IN FOR
CHANCES FOR SNOW OR EVENTUALLY A MIXED BAG. IN ADDITION TO PRECIP
CHANCES TEMPS SHOULD RISE TO ABOVE FREEZING FOR HIGHS FRI-SUN INTO
THE 30S. EURO GUIDANCE CONTINUES TO POINT TOWARDS HIGHS IN THE 40S
AND MEX NOW TRYING FOLLOW SUIT. WHILE NOT IMPOSSIBLE...AMOUNT OF
SNOWPACK ACROSS THE AREA WILL LIKELY LIMIT FULL
POTENTIAL...ESPECIALLY FRIDAY WITH BEST CHANCE FOR 40S POSSIBLY BY
SUNDAY. THE INCREASING TEMPS WILL CAUSE A RELEASE OF THE SNOWPACK
AND WILL RESULT IN RISING RIVER LEVELS AND INCREASED CONCERNS FOR
BOTH RIVER AND LOW LYING FLOODING. HAVE GENERALLY KEPT FORECAST AS
IS THROUGH THIS TIME FRAME WITH TIMING/TRACK OF EACH WAVE LIKELY TO
VARY OVER THE NEXT SEVERAL DAYS. FOR NOW WITH SO MANY OTHER DETAILS
IN THE HWO...WILL HOLD OFF ON MENTION IN HWO AS DURATION OF RELEASE
COULD BE OVER A LONG ENOUGH PERIOD TO KEEP RISKS MINIMIZED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1139 PM EST SUN JAN 5 2014
ARCTIC BNDRY DEMARCATING BACK EDGE OF SIG LK ENHANCEMENT EAST OF
KSBN TERMINAL NOW YET WILL IMPACT KFWA 05-06Z. OTRWS -SHSN WITHIN
ARCTIC WEDGE DECAYING RAPIDLY AND XPC ACCUMULATING SNOW OVR AFT 06Z.
HWVR INFLUX OF ARCTIC WEDGE AND PLUMMETING TEMPS WILL YIELD STRONG
GRADIENT WIND GUSTS TO AOA 35KTS AND SPURN SIG BLOWING AND DRIFTING
SNOW THROUGH REMAINDER OF THE OVERNIGHT AND PROBABLY MOST OF
TOMORROW.
WILL REACCESS MONDAY WINDS WITH LTR 12Z ISSUANCE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER STORM WARNING UNTIL 7 AM EST MONDAY FOR INZ006>009-017-
018-025>027-033-034.
WIND CHILL WARNING UNTIL 8 PM EST /7 PM CST/ TUESDAY FOR
INZ003>009-012>018-020-022>027-032>034.
BLIZZARD WARNING UNTIL 7 AM EST /6 AM CST/ MONDAY FOR INZ003>005-
012>016-020-022>024-032.
MI...WINTER STORM WARNING UNTIL 7 AM EST MONDAY FOR MIZ079>081.
WIND CHILL WARNING UNTIL 8 PM EST TUESDAY FOR MIZ077>081.
BLIZZARD WARNING UNTIL 4 AM EST MONDAY FOR MIZ077-078.
OH...WINTER STORM WARNING UNTIL 7 AM EST MONDAY FOR OHZ001-002-004-
005-015-016-024-025.
WIND CHILL WARNING UNTIL 8 PM EST TUESDAY FOR OHZ001-002-004-005-
015-016-024-025.
LM...HEAVY FREEZING SPRAY WARNING UNTIL 4 AM EST TUESDAY FOR LMZ043-
046.
GALE WARNING UNTIL 4 AM EST TUESDAY FOR LMZ043-046.
&&
$$
UPDATE...T
SYNOPSIS...LASHLEY
SHORT TERM...AGD
LONG TERM...FISHER
AVIATION...T
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1046 PM CST Sun Jan 5 2014
.UPDATE...
ISSUED AT 1032 PM CST SUN JAN 5 2014
Updated for 06z aviation.
&&
.SHORT TERM...(This Evening through Monday)
ISSUED AT 323 PM CST SUN JAN 5 2014
Current radar Mosaic indicates temporary weakening of pcpn echoes
west of the MS river, however some enhancement is also indicated
over sern MO/swrn IL associated with the exit region of an upper
level jet.
Meanwhile, the nwrn half of the region is under very rapid cold
air advection behind a ewd-departing sfc low, and these very raw
conditions will rapidly sweep across the rest of the region during
the late afternoon. Flash freezing of water on roads is expected.
Dual Pol correlation coefficient from KVWX radar was clearly
showing the rain/snow line beginning to accelerate ewd. Any
intervals of freezing rain or sleet are expected to be even
briefer in duration than they have been up to now.
The HRRR model suggests that the aforementioned enhanced area of
snowfall over sern MO/swrn IL will fill in over most of the region
late this afternoon, except west of Poplar Bluff MO, where
snowfall will taper off rapidly to flurries by sunset.
After sunset, little measurable snowfall is forecast, but
lingering moisture in the new arctic air mass will probably
produce flurries across the entire region into part of the
overnight hours.
A secondary mid level shrtwv will produce clouds and may produce
more flurries during the day Mon. We will flirt with record lows
tonight and Mon night and will shatter minimum highs for Mon.
Dangerous wind chill readings early Mon morning will range from
-20 south to -30 north. The brisk breeze will slowly decrease during
the day. The sun will return Tue, along with "warmer" temps in the teens.
.LONG TERM...(Monday Night through Sunday)
ISSUED AT 323 PM CST SUN JAN 5 2014
Extended models are in general agreement but there are always issues
in the details.
Early Wednesday there is a broad trough over the eastern US with a
more zonal flow over the western US. By Thursday two main troughs
can be seen to our west. One over KS and OK with another off the NW
coast of the US. The first impulse is slow to get here as the
overall pattern changes to a trough in the west and more zonal flow
in the east. But we will have overrunning precipitation both
Wednesday and Thursday.
By 00Z Saturday, the GFS, GEM, and ECMWF want to carve out an upper
level low over the southwest US or Mexico. After that the speed and
intensity of the wave is in question as it moves toward us.
The initial precipitation type will be snow or freezing rain with the
GFS being the warmer model aloft and hence the chance of freezing
rain. Snowfall accumulations will be light but will have to be
monitored. Held off on any ice accumulation until the models have a
better handle on the situation. The good news is that by Friday warm
air has taken over the entire CWA and expect liquid precipitation
over the region through the weekend.
&&
.AVIATION...
ISSUED AT 1032 PM CST SUN JAN 5 2014
Latest ir satellite loop and sfc obs indicate clearing poised to
move into the area with some sct mid deck. This will give vfr conditions
after 6z. However the forecast sounding and time height x-sections
would indicate another low deck returning around sunrise Monday.
Gusty nw winds will persist through 00z Tuesday then lose the gust
after 00z Tuesday.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...WIND CHILL ADVISORY until 9 AM CST Tuesday FOR ILZ084>094.
WIND CHILL WARNING until 9 AM CST Tuesday FOR ILZ075>078-080>083.
MO...WIND CHILL ADVISORY until 9 AM CST Tuesday FOR MOZ076-086-087-
100-107>112-114.
IN...WIND CHILL WARNING until 9 AM CST Tuesday FOR INZ081-082-085>088.
KY...WIND CHILL ADVISORY until 9 AM CST Tuesday FOR KYZ001>022.
&&
$$
UPDATE...KH
SHORT TERM...DB
LONG TERM...PS
AVIATION...KH
AREA FORECAST DISCUSSION
NWS GRAY ME
1254 AM EST MON JAN 6 2014
.SYNOPSIS...
LOW PRESSURE WILL TRACK NORTH ALONG A STALLED FRONTAL BOUNDARY
WELL TO THE WEST OF THE FORECAST AREA OVERNIGHT. LOW PRESSURE WILL
CONTINUE NORTH THROUGH WESTERN QUEBEC ON MONDAY AND WILL DRIVE A
STRONG COLD FRONT THROUGH THE REGION MONDAY AFTERNOON. A STRONG
WESTERLY FLOW WILL PREVAIL BEHIND THE FRONT MONDAY NIGHT THROUGH
TUESDAY. HIGH PRESSURE WILL BUILD IN FROM THE SOUTH WEDNESDAY
THROUGH THURSDAY. A WARM FRONT WILL LIFT NORTH INTO THE FORECAST
AREA THURSDAY NIGHT AND WILL PUSH NORTHEAST OF THE REGION ON
FRIDAY. A COLD FRONT WILL PUSH THROUGH THE REGION FROM THE WEST ON
SATURDAY WITH HIGH PRESSURE TO FOLLOW ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
UPDATED TO INPUT LATEST OBSERVED DATA. HAVE ADJUST POP UP FOR ALL
ZONES OVERNIGHT PER LATEST RADAR. HAVE ADJUSTED PRCP TYPE TO
ACCOUNT FOR AREAS THAT CLIMBED ABOVE FREEZING...THE MID COAST /EG
RKD IS 36/ AND NH COAST /PSM IS 33/ AND SOME DOWNSLOPE AREAS IN
NRN NH...LIKE HIE THAT IS 41 DEGREES AT MIDNIGHT WHILE BML IS 29.
HAVE ADJUSTED TEMPS THRU MONDAY PER LATEST OBS AND TRENDS.
OTRW -FZRA CONTINUES WITH SOME SN/PL NRN MOST ZONES FOR A WHILE
WITH ACCUMULATING ICE...NO MORE THAN A QUARTER OF AN INCH...SO
WILL CONT ALL ADVISORIES. FZRA CHANGES TO RA FROM S TO N AND
COAST TO INLAND AREAS AROUND DAYBREAK INTO MONDAY MORNING.
PREVIOUS DISCUSSIONS...
1030PM UPDATE...
FORECAST STILL ON TRACK WITH FREEZING RAIN NOW SPREADING INTO THE
AREA FROM THE WEST. SOME AREAS OF SLEET AND SNOW ALSO OCCURRING IN
NORTHERN AREAS... BUT THIS WILL TRANSITION TO FREEZING RAIN OVERNIGHT.
630PM UPDATE...
HAVE ADJUSTED THE FORECAST TO BETTER REFLECT TIMING OF
PRECIPITATION AS IT ENTERS THE AREA TONIGHT. THE HEAVIEST BATCH OF
PRECIPITATION IS MOVING THROUGH NEW YORK STATE LATE THIS AFTERNOON
AND WILL MOVE INTO NEW HAMPSHIRE AND NORTHWEST MAINE THIS EVENING.
STILL EXPECTING DAMMING TO BE DEEP ENOUGH TO ALLOW PRECIPITATION
TO FALL AS SNOW AND SLEET FOR A GOOD TIME PERIOD ACROSS MUCH OF
MAINE AND NORTHERN NEW HAMPSHIRE... WHILE WARM ADVECTION ALOFT
WILL BE SUFFICIENT FOR FREEZING RAIN ACROSS SOUTHERN NEW HAMPSHIRE
AND FAR SOUTHWEST MAINE. PRECIPITATION MAY BE LIGHTER AT THE COAST
AS PRECIPITATION HERE MAY BE DRIVEN MORE BY MOIST ADVECTION OFF
THE OCEAN. STILL EXPECTING TEMPERATURES TO WARM EARLY MONDAY
MORNING... CHANGING FREEZING RAIN TO RAIN. ONE POSSIBLE CONCERN IS
THAT WHILE PRECIPITATION MAY CHANGE TO RAIN WHEN AIR TEMPERATURES
RISE ABOVE FREEZING... GROUND TEMPERATURES WILL LIKELY STAY COLD
DUE TO WEEKS OF SUB FREEZING TEMPERATURES FOR MANY AREAS. THIS
COULD ALLOW RAIN TO CONTINUE TO FREEZE ON GROUND SURFACES LIKE
ROADS EVEN AFTER TEMPERATURES WARM ABOVE FREEZING.
WINTER WEATHER ADVISORIES HAVE BEEN CONVERTED TO FREEZING RAIN
ADVISORIES FOR SOUTHERN AREAS WHERE PRECIPITATION WILL BE ALMOST
ENTIRELY FREEZING RAIN. TIMING HAS ALSO BEEN EXTENDED TO ACCOUNT
FOR A POTENTIALLY SLOWER WARM UP OVERNIGHT AND MONDAY MORNING.
ORIGINAL DISCUSSION...
VERY INTERESTING SETUP WITH LOW PRESSURE PASSING WELL TO OUR WEST
OVERNIGHT. HOWEVER...AT THE SAME TIME...A WEAK AREA OF LOW
PRESSURE HAS ALREADY FORMED ALONG THE MID ATLANTIC COASTLINE. THIS
IS AHEAD OF AND TO THE NORTH OF ALL MODELED GUIDANCE AT THIS TIME.
EVEN THE MESO MODELS ARE HAVING A DIFFICULT TIME...AS THEY ARE
NOT CAPTURING THE PRECIPITATION OVER SOUTHERN NEW ENGLAND AT THE
MOMENT.
IN ANY CASE...PRECIPITATION WILL ENTER THE FORECAST AREA THIS
EVENING. HAVE LEANED TOWARDS A COLD SOLUTION...A TAD COOLER THAN
ALL AVAILABLE GUIDANCE. ATMOSPHERE STILL VERY COLD AND DRY...AND
THERE WILL BE PLENTY OF EVAPORATION COOLING AS EVIDENT ON 12Z GYX
SOUNDING.
THEREFORE...HAVE EXPANDED THE WINTER WEATHER ADVISORIES TO INCLUDE
THE COASTLINE. LATEST HRRR KEEPS TEMPERATURES BELOW FREEZING FOR
MUCH OF THE COAST THROUGH AT LEAST MIDNIGHT BEFORE THE WARM UP.
WARM UP MAY BE A TAD EARLIER AT PSM AND ALONG THE NH SEACOAST.
ENOUGH DRY AIR IN PLACE TO POSSIBLY HOLD FOR SEVERAL HOURS OF
SNOWFALL IN THE USUAL SUSPECT LOCATION OF THE FOOTHILLS. GFS
ACTUALLY PICKS UP ON THIS FEATURE.
USED A NON-DIURNAL CURVE FOR THE OVERNIGHT MINS.
HAVE SENT FORECAST SNOWFALL AND ICE MAPS. ICE WILL BE A SENSITIVE
ISSUE AS WE HAVE HAD REPORTS OF ICE STILL IN THE TREES FROM THE
ICE STORM PRIOR TO THE HOLIDAYS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 AM TUESDAY/...
STRONG COLD FRONT WILL CROSS THE REGION MONDAY AFTER A SIGNIFICANT
WARM UP DURING THE AFTERNOON. TEMPERATURES WILL GO FROM WELL IN THE
40S...TO A DEEP FREEZE OVER A SHORT PERIOD OF TIME. STRONGEST
WINDS WILL HOLD OFF UNTIL THE PASSAGE OF THE UPPER LEVEL TROUGH.
&&
.LONG TERM /TUESDAY THROUGH MONDAY/...
MORE BITTERLY COLD ARCTIC AIR IS EXPECTED TUESDAY THRU WEDNESDAY
ON GUSTY WESTERLY WINDS WHICH WILL CREATE EXTREMELY COLD WIND
CHILLS. THE UPSLOPE WESTERLY FLOW UNDER THE UPPER LEVEL SYSTEM WILL
CREATE SCATTERED SNOW SHOWERS ACROSS THE NORTH AND MOUNTAIN ZONES.
FINALLY AS HIGH PRESSURE BUILDS IN FROM THE WEST AND THE AIR MASS
CONTINUES TO WARM WE SHOULD SEE TEMPERATURES CLIMB BACK TO MORE
NORMAL LEVELS ALONG WITH LIGHTER WINDS ON THURSDAY. LATE
THURSDAY NIGHT AND FRIDAY A WARM FRONT WITH WARM ADVECTION ALOFT
WILL MOVE ACROSS NORTHERN NEW ENGLAND CREATING SOME LIGHT SNOW
SHOWERS ON FRIDAY INTO FRIDAY EVENING. TEMPERATURES SHOULD REMAIN
COLD ENOUGH TO BE SNOW. HIGH PRESSURE AND A WARMER AIR MASS WILL
TAKE CONTROL FOR SATURDAY.
USED THE SUPERBLEND FOR TEMPERATURES AND POPS.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
SHORT TERM /THROUGH MONDAY NIGHT/...IFR/LIFR EXCEPT MVFR/VFR AT
HIE DUE TO STRONG DOWNSLOPING SE WINDS. FZRA MAIN CONCERN WITH RA
ALONG THE COAST AT PSM AND RKD AND DOWNSLOPE NRN NH AREAS LIKE
HIE. OTRW FZRA CHANGES TO RA EARLY TO MID MORNING HOURS ON MONDAY
AT CON...AUG AND LEB. ADDED LLWS TO TAFS FOR STRONG SSE FLOW THAT
BECOMES SSW. CONDITIONS IMPROVE MONDAY AFTERNOON AND EVENING AS A
COLD FNT MOVES TO THE EAST. -SHSN WILL PERSIST AT HIE AND LIKELY
TO STAY MVFR MONDAY NIGHT.
LONG TERM...
MVFR IN SCATTERED SNOW SHOWERS FOR MOUNTAIN AREAS TUESDAY. GUSTY
WEST WINDS THRU TUESDAY NIGHT AND INTO WEDNESDAY. MVFR CONDITIONS
POSSIBLE FRIDAY IN SCATTERED SNOW SHOWERS.
&&
.MARINE...
SHORT TERM /OVERNIGHT THROUGH MONDAY NIGHT/...UPDATED TO INPUT
LATEST OBSERVED DATA. WILL CONT THE SCA FOR CASCO BAY AND GLW ALL
OTHER COASTAL WATER ZONES AS SOUTHERLY FLOW INCREASE AHEAD OF THE
APPROACHING COLD FRONT. WINDS SHIFT TO THE WEST BEHIND THE FNT AND
WILL STAY RATHER STRONG SO SCA/GLW MAY BE NEEDED MONDAY NGT AS
WELL. A FEW TWEAKS TO THE PREVIOUS FCST BUT NO SIGNIFICANT CHANGES
AT THIS TIME.
LONG TERM...
AN EXTENDED PERIOD OF FAIRLY STRONG WINDS AND ROUGH SEAS WITH AT
LEAST SCA CONDITIONS (AND POSSIBLY GALES OVER THE OPEN WATERS)
THRU TUESDAY NIGHT AND INTO WEDNESDAY. WINDS THEN SEAS SLOWLY EASE
UP LATE WEDNESDAY THRU THURSDAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...FREEZING RAIN ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
MEZ018-023-024.
WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR MEZ007>009-
013-014.
WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR
MEZ012-019>022-025>028.
NH...FREEZING RAIN ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
NHZ005>010-013-014.
WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR NHZ001-002.
WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR
NHZ003-004.
MARINE...SMALL CRAFT ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR ANZ153.
GALE WARNING UNTIL 3 PM EST THIS AFTERNOON FOR ANZ150>152-154.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
452 AM EST MON JAN 6 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 448 AM EST MON JAN 6 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP UPR TROF IN
CENTRAL NAMERICA AS ARCTIC/POLAR BRANCHES ARE IN THE PROCESS OF
PHASING...WITH THE AXIS OF LOWEST HGTS STRETCHING FM HUDSON BAY INTO
THE UPR MS RIVER VALLEY. WITHIN THE CORE OF THE COLDEST AIR...00Z
RAOBS SHOW H5/H85/H925 TEMPS AS LO AS -45C/-34C/-34C. THE PHASING OF
THE UPR BRANCHES IS SUPPORTING A DEEPENING SFC LO MOVING NNEWD INTO
SE ONTARIO. ALTHOUGH THE SYNOPTIC SCALE FORCING/PCPN ASSOCIATED WITH
THIS SFC LO ARE PASSING TO THE E OF UPR MI...SHARPENING CYC NNW FLOW
ON THE NW FLANK OF THE LO AND AREA OF DPVA/DEEP LYR QVECTOR CNVGC/
DEEPENING MID LVL MSTR AHEAD OF THE ARCTIC BRANCH SHRTWV ARE
IMPACTING MAINLY THE E HALF OF UPR MI...CAUSING AN INCRS IN LES
INTENSITY/COVERAGE IN THE FAVORED SN BELTS. AN AREA OF DEEPER MSTR
ALSO STRECHES FM NW ONTARIO S INTO MN UNDER THE AXIS OF LOWER HGTS.
TEMPS REMAIN WELL BLO NORMAL. 00Z H85 TEMPS OVER UPR MI RANGED FM
ABOUT -19C OVER THE SE TO -25C OVER THE W... SUPPORTING SFC TEMPS AS
LO AS -20F OVER THE FAR W NEAR THE WI BORDER EARLY THIS MRNG. THE
MORE NNW FLOW OFF LK SUP HAS MODERATED THE AIRMASS DOWNWIND OF THE
LK OVER THE ERN CWA...WHERE TEMPS NEAR LK SUP REMAIN CLOSE TO 10F.
THE INCRSG WINDS HAVE CAUSED WIND CHILLS TO FALL AS LO AS -35 TO
-40F OVER THE WRN CWA.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON HEADLINES RELATED TO
TEMPS/WIND CHILLS AS WELL AS LES/BLSN.
TDAY...SFC LO OVER SE ONTARIO EARLY THIS MRNG IS PROGGED TO LIFT
NEWD INTO QUEBEC AND INTENSIFY AS AXIS OF LOWEST HGTS ALF DRIFTS E
ACROSS THE UPR LKS. ALTHOUGH THE AREA OF SHARPER QVECTOR CNVGC TO
THE E OF THE UPR TROF IS PROGGED TO DRIFT TO THE E AND AWAY FM
NEWBERRY BY LATE AFTN...AREA OF DEEPER MSTR/CORE OF COLDER AIR NOTED
TO THE W IS PROGGED TO DRIFT E THRU THE UPR LKS AS WELL. THE COLDEST
H85 TEMPS ARE FCST TO PASS TO THE S THRU WI...BUT THE STEADILY
BACKING LLVL FLOW TOWARD THE W BY 00Z TUE ASSOCIATED WITH THE
DEPARTING SFC LO TO THE NE WL ALLOW FOR LESS LK SUP MODERATION OF
THE BITTERLY COLD AIRMASS. THE FOCUS OF THE HIER LES POPS WL SHIFT
AS WELL WITH THESE BACKING WINDS. ALTHOUGH ABSENCE OF DGZ WITH
BITTERLY COLD AIR WL LIMIT SN ACCUMS OVER THE W...ARRIVAL OF DEEPER
MSTR WL KEEP CONTINUOUS -SHSN GOING. SMALL SN FLAKES WL EFFICIENTLY
REDUCE VSBY AS BLSN INCREASES WITH SLOWLY INCRSG WINDS. EXPECT
SOMEWHAT HEAVIER SHSN OVER THE E WHERE LES ADVY IS IN PLACE GIVEN
SOME LINGERING DYNAMIC FORCING/WARMER AIR THAT DOES NOT HAMPER SN
GROWTH AS MUCH... BUT THE SHIFTING WINDS WL TEND TO CAUSE THE LES
BANDS TO DRIFT AS WELL. AS FOR TEMPS/WIND CHILLS...EXPECT LTL IF ANY
DIURNAL RECOVERY WITH BACKING LLVL FLOW LIMITING LK MODERATION. OVER
THE E...THIS BACKING FLOW MAY CAUSE TEMPS TO FALL. SINCE WIND SPEEDS
WL BE ON THE INCRS AS WELL...GOING WIND CHILL HEADLINES SEEM TO BE
ON TRACK.
TNGT...MODELS HINT ANOTHER SHRTWV DIVING SEWD ARND SLOWLY DEPARTING
UPR TROF AXIS WL MOVE INTO THE UPR LKS...BRINGING ANOTHER ROUND OF
DPVA/DEEP LYR QVECTOR CNVGC THAT MAINTAINS DEEPER MSTR. AS THE SFC
FLOW BACKS WITH LAND BREEZE ENHANCEMENT...LLVL CNVGC WL INCRS OVER
NRN ONTONAGON/CENTRAL HOUGHTON COUNTIES AND NEAR LK SUP E OF
MUNISING. THIS INCRSG LAND BREEZE COMPONENT WL TEND TO ADVECT LESS
MODIFIED AIR INTO THE CWA AND OFFSET SLOWLY MODERATING H85 TEMPS
WITH PASSAGE OF COLDEST CORE TO THE E. SINCE THE LLVL WINDS ARE FCST
TO INCRS AS WELL...WARNING THRESHOLD WIND CHILLS ARE LIKELY OVER
ALMOST ALL OF THE CWA.
AS FOR HEADLINES...GOING WIND CHILL WARNINGS APPEAR TO BE ON TRACK
EVEN THOUGH MORE LK MODIFIED AIR HAS MAINTAINED HIER TEMPS OVER
ABOUT THE E HALF OF THE CWA. BACKING/INCRSG WINDS LATER TDAY/TNGT
SHOULD ADVECT SUFFICIENTLY COLD AIR OVER THE ENTIRE CWA TO JUSTIFY
MAINTAINING ALL WIND CHILL WRNGS. ALTHOUGH SN AMOUNTS OVER THE W ARE
NOT LIKELY TO REACH ADVY THRESHOLDS...OPTED TO ISSUE AN LES ADVY FOR
ONTONAGON COUNTY THRU THE KEWEENAW THRU TUE TO ACCOUNT FOR THE
FREQUENT WHITEOUTS THAT WL LIKELY OCCUR WITH THE FALLING AND BLOWING
OF THE SMALL SN FLAKES. EXTENDED THE LES ADVY FOR ALGER/LUCE
COUNTIES THRU TUE AS WELL GIVEN THE POTENTIAL FOR HEAVIER SHSN
ESPCIALLY NEAR LK SUP E OF PICTURED ROCKS IN THE SHARPER LLVL CNVGC
THAT WL DVLP WITH SHARPENING LAND BREEZE CNVGC/WARMER H85 TEMPS THAT
WL NOT IMPACT SN GROWTH AS MUCH AS OVER THE W.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 448 AM EST MON JAN 6 2014
THE 500MB LOW RESPONSIBLE FOR THE ACTIVE WEATHER ACROSS THE GREAT
LAKES THIS WEEK WILL BE OVER QUEBEC TUESDAY MORNING. THIS LOW WILL
LINGER A TROUGH OVER THE GREAT LAKES THROUGH THE DAY TUESDAY AND
WEDNESDAY. AT THE SURFACE...HIGH PRESSURE WILL SINK TOWARDS THE GULF
OF MEXICO. THE SURFACE LOW OVER THE LOWER LAKES MONDAY NIGHT WILL
MAKE ITS WAY INTO QUEBEC BY TUESDAY...KEEPING A WEAK TROUGH OVER
EASTERN LAKE SUPERIOR THROUGH WEDNESDAY. OVERALL...UPPER MI WILL
REMAIN IN WEST-NORTHWEST FLOW THROUGH THE FIRST PORTION OF THE LONG
TERM...CAUGHT BETWEEN THE HIGH IN THE SOUTHEAST AND THE LOW IN
QUEBEC. THOUGH WINDS WILL BE GUSTY THROUGH MOST OF TUESDAY...THEY
WILL GRADUALLY LESSEN AS THE HIGH MAKES ITS WAY INTO THE CWA TUESDAY
NIGHT INTO WEDNESDAY. WITH THE COLD ARCTIC AIR IN PLACE...LES WILL
CONTINUE IN WNW-WIND FAVORED SNOWBELTS. WITH DWINDLING
MOISTURE/EXTREME COLD...SNOW RATIOS WILL BE UNSUPPORTIVE OF
SIGNIFICANT ACCUMULATIONS ACROSS THE AREA FOR THIS TIME PERIOD. FOR
NOW HAVE 2 TO 4 INCHES OF ACCUMULATION FROM TUESDAY MORNING INTO
WEDNESDAY MORNING FOR EASTERN ALGER/LUCE COUNTY...AND 1 TO 2 INCHES
ACROSS ONTONAGON...HOUGHTON...AND KEWEENAW COUNTY.
THE MAIN CONCERN WILL BE LOWERED VISIBILITY DUE TO THE SMALL FLAKE
SIZE AND BLOWING SNOW/FROM GUSTY WNW WINDS/ NEAR THE LAKESHORE ALL
DAY TUESDAY...AND WIND CHILLS THROUGH LATE TUESDAY MORNING. FOR
HEADLINES...HAVE LES ADVISORY THROUGH TUESDAY IN WNW WIND FAVORED
SNOWBELTS...MAINLY ONTONAGON....NORTHERN
HOUGHTON...KEWEENAW...ALGER...AND LUCE COUNTIES TO ACCOUNT FOR THE
SNOW/BLOWING SNOW/WIND CHILL. ELSEWHERE...SOLELY THE WIND CHILL
WARNING REMAINS IN EFFECT. WIND CHILLS TUESDAY MORNING WILL RANGE
FROM -50F TO -25F ACROSS THE FORECAST AREA...WITH THE COLDEST
READINGS ACROSS THE INTERIOR WEST.
THE HIGH WILL GRADUALLY CROSS THE GREAT LAKES LATE WEDNESDAY INTO
THURSDAY...AND THEN REACH THE NEW ENGLAND STATES BY THURSDAY NIGHT.
AS THE HIGH MOVES OUT...WINDS BACK TO THE SOUTHWEST. THIS BRINGS
EXTREMELY DRY AIR INTO MUCH OF THE CWA BY EARLY WEDNESDAY
EVENING...STARTING A DISSIPATING TREND TO THE LES THROUGH THURSDAY
MORNING. ADDITIONALLY...WITH WINDS BACKING SOUTHWEST...MOST OF THE
REMAINING LES WILL MOVE OFFSHORE INTO LAKE SUPERIOR. THE BEST CHANCE
FOR SNOW SHOWERS ON THURSDAY IS OVER THE KEWEENAW.
MODELS BEGIN TO DISAGREE LATE THURSDAY INTO FRIDAY ON HOW TO HANDLE
AN UPPER LEVEL TROUGH MOVING INTO THE NORTHERN PLAINS...BOTH WITH
THE TIME AND STRENGTH OF THE OVERALL FEATURE. THE ECMWF BRINGS A
MORE SHALLOW TROUGH ACROSS THE GREAT LAKES FRIDAY NIGHT/SAT
MORNING...WHEREAS THE GFS BRINGS A DEEPER TROUGH THROUGH ON SATURDAY
EVENING. BY THIS TIME...THE ECMWF HAS ZONAL FLOW ALOFT FOR UPPER MI.
THE GEM SEEMS TO BE THE MIDDLE OF THE ROAD...BRINGING THE TROUGH
THROUGH THE GREAT LAKES SATURDAY AFTERNOON...WITH A STRENGTH SIMILAR
TO THAT OF THE ECMWF. BY SUNDAY AND MONDAY...THESE DIFFERENCES ARE
EXACERBATED...ESPECIALLY AT THE SURFACE. THE ECMWF KEEPS A WEAK SURFACE
TROUGH OVER THE GREAT LAKES THROUGH SUNDAY AFTERNOON...AND THEN
BRINGS A SURFACE HIGH ACROSS THE NORTHERN PLAINS INTO THE GREAT LAKES
FOR MONDAY. THE GFS BRINGS A CLOSED LOW PRESSURE SYSTEM ACROSS
MANITOBA AND INTO JAMES BAY...WHICH KEEPS A TROUGH OVER UPPER MI.
WILL KEEP THE CONSENSUS POPS FOR NOW GIVEN SUCH DRAMATIC DIFFERENCES.
ON A POSITIVE NOTE...MODELS TRENDING UPWARD WITH TEMPERATURES THROUGH
THE PERIOD...WITH HIGHS IN THE UPPER 20S AND LOW 30S BY NEXT WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1234 AM EST MON JAN 6 2014
EXTREME COLD AIRMASS MOVING ACROSS THE UPPER GREAT LAKES WILL ALLOW
FOR LAKE EFFECT SNOW SHOWERS TO CONTINUE THROUGH THE PERIOD. KCMX
WILL LIKELY SEE LIGHT SNOW THROUGH THE PERIOD. DUE TO THE FINE SNOW
FLAKES AND BLOWING SNOW UNDER THE ARCTIC AIRMASS...EXPECT CONDITIONS
TO REMAIN IFR TONIGHT...THEN DETERIORATE INTO LIFR CONDITIONS ON
MONDAY AS THE FLOW BECOMES MORE WESTERLY AND THE POLAR VORTEX MOVES
OVERHEAD. KIWD WILL ALSO SEE FAIRLY PERSISTENT LIGHT SNOW AND BLSN
TONIGHT WITH IFR VSBYS. HOWEVER...AS THE FLOW BECOMES MORE WESTERLY
ON MONDAY EXPECT THE SNOW TO DIMINISH AND VSBYS TO IMPROVE BY MON
EVENING. AT KSAW...SOME LIGHT SNOW/FLURRIES TONIGHT INTO MONDAY
MORNING WILL LIKELY YIELD MVFR CONDITIONS...BUT THE EXPECTATION IS
THAT WHEN THE SURFACE FLOW BECOMES MORE W-NW ON MONDAY THAT VFR
CONDITIONS WILL DEVELOP.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 448 AM EST MON JAN 6 2014
WITH SHARPENING PRES GRADIENT AND FLOW OF ARCTIC AIR OVER THE
RELATIVELY WARM LK WATERS...EXPECT WNW WINDS 30 KTS TO GALES TO 35
KTS THRU TONIGHT INTO TUESDAY EVENING. MAINTAINED GOING GALE
WARNINGS. THE COMBINATION OF THE BITTER COLD/SIGNIFICANT WAVE ACTION
WILL RESULT IN WIDESPREAD HEAVY FREEZING SPRAY AS WELL...SO LEFT THE
HEAVY FREEZING SPRAY WARNINGS IN EFFECT THROUGH WEDNESDAY MORNING.
OTHERWISE...HIGH PRESSURE WILL MAKE ITS WAY SOUTH OF LAKE SUPERIOR
BY MID WEEK...BUT A PERSISTANT LOW PRESSURE TROUGH NORTH OF THE LAKE
WILL KEEP WNW WINDS GUSTING TO 15 TO 25 KTS THROUGH THURSDAY.
TOWARDS THE LATTER PORTION OF THE WEEK...ANOTHER LOW PRESSURE TROUGH
WILL APPROACH THE GREAT LAKES FROM THE NORTHERN PLAINS...BACKING
WINDS TO THE SOUTHWEST AT 15 TO 25 KNOTS FOR THURSDAY AND FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL WARNING UNTIL 11 AM EST /10 AM CST/ TUESDAY FOR
MIZ001>005-009>013-084.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ014-
085.
WIND CHILL WARNING FROM 7 PM THIS EVENING TO 11 AM EST TUESDAY
FOR MIZ006-007-014-085.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST TUESDAY FOR MIZ001>003-
006-007.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ WEDNESDAY
FOR LSZ162-243>245-248>251-263>267.
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LSZ265-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...MCD
AVIATION...MRD
MARINE...KC/MCD
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1242 AM EST MON JAN 6 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 445 PM EST SUN JAN 5 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW THE CENTER OF AN ELONGATED
POLAR VORTEX OVER NRN ONTARIO. A SHORTWAVE WAS DIVING SE THRU THE
NRN PLAINS...CAUSING THE ELONGATION OF THE VORTEX INTO THE NRN
PLAINS. THE CORE OF THE VERY COLD ARCTIC AIR MASS RESIDES FROM NRN
ONTARIO INTO SCNTRL CANADA AND THE FAR NRN PLAINS. PER 12Z RAOBS...
850MB TEMPS ARE IN THE -29C TO -34C RANGE ACROSS SCNTRL CANADA INTO
THE FAR NCNTL CONUS. LATEST RUC ANALYSIS INDICATES 850MB TEMPS
RANGING FROM -25C OVER WRN LAKE SUPERIOR TO AROUND -19C OVER FAR SE
LAKE SUPERIOR. OF COURSE...THIS IS LEADING TO LES OFF LAKE SUPERIOR
IN WNW LOW-LEVEL FLOW. HOWEVER...VERY DRY AIR MASS/LOW INVERSION
(3-5KFT LOWEST W PER LATEST RUC) IS GREATLY LIMITING LES INTENSITY.
PLUS...IT DOESN`T HELP THAT VERY COLD AIR HAS ELIMINATED THE DGZ FOR
THE WRN LAKE SUPERIOR LES. ON THE OTHER HAND...THE RESULTING SMALL
SNOWFLAKES ARE LEADING TO SHARPLY REDUCED VIS WHERE LES IS OCCURRING
(VIS AT KCMX HAS BEEN DOWN TO 1/2SM AT TIMES THIS AFTN...AND WEBCAMS
HAVE SHOWN QUITE LOW VIS AT TIMES).
AS THE ELONGATED POLAR VORTEX SWINGS INTO THE UPPER GREAT LAKES
MON...THERE WILL BE A SIGNIFICANT LIFTING OF THE INVERSION AND
DEEPENING OF MOISTURE. THIS WILL GRADUALLY BEGIN TONIGHT...BUT WILL
LARGELY TAKE PLACE DURING THE DAY MON. AS A RESULT...THERE WILL BE A
NOTABLE INCREASE IN LAKE EFFECT SNOW COVERAGE...AND INTENSITY WILL
INCREASE AS WELL. HOWEVER...WITH THE COLD AIR MASS ELIMINATING THE
DGZ...SNOW-TO-WATER RATIOS WILL BE POOR...PROBABLY DOWN TOWARD 10 TO
1 AS HAS BEEN OBSERVED IN PAST ARCTIC AIR MASSES SIMILAR TO THE
MAGNITUDE OF THIS ONE. SNOW WILL BE POWDERY AND VERY EFFECTIVE AT
REDUCING VIS. WITH THE INCREASE IN LES COVERAGE...WHITEOUTS WILL
PROBABLY BECOME NEARLY CONSTANT IN THE SNOWBELTS FAVORED BY NW WINDS
LATE TONIGHT AND ESPECIALLY MON. TONIGHT...LOW-LEVEL WINDS WILL
VEER MORE TOWARD THE NNW IN RESPONSE TO THE DEEPENING LOW LIFTING
NNE THRU THE LWR LAKES. THE VEERING WILL BE MORE PRONOUNCED OVER THE
ERN LAKE WHERE LAND BREEZE ENHANCEMENT OFF ONTARIO WILL AID THE
VEERING. THIS WILL LEAD TO STRENGTHENING CONVERGENCE INTO
ALGER/LUCE/SCHOOLCRAFT COUNTIES. WITH THE DGZ STILL LINGERING IN THE
LOWER PART OF THE CONVECTIVE LAYER IN THAT AREA...SHOULD BE ABLE TO
GET ACCUMULATIONS INTO THE 2 TO 4 INCH RANGE. COMBINED WITH SOME
INCREASE IN WINDS TO GENERATE BLSN...ADVY LOOKS ON TRACK FOR THAT
AREA. EVEN THOUGH THE DGZ IS ELIMINATED MON...SIMILAR ACCUMULATIONS
SHOULD OCCUR GIVEN LINGERING ENHANCED CONVERGENCE AND DEEP MOISTURE
PROFILE. OUT W...SNOW ACCUMULATIONS WILL BE ON THE ORDER OF 1-2 TO
PERHAPS 3IN/12HR TONIGHT/MON.
AS FOR TEMPS/WIND CHILLS...WITH LOW-LEVEL WINDS VEERING TONIGHT...
THERE SHOULD BE AN INCREASE IN LAKE EFFECT CLOUD COVER ACROSS MUCH
OF THE AREA. HAVE THUS OPTED TO RAISE MINS A FEW DEGREES IN MANY
LOCATIONS. TEMPS MAY STILL BOTTOM OUT AROUND -25F OVER THE FAR W
ALONG THE MI/WI BORDER...BUT IF CLOUD COVER IS QUICKER TO DEVELOP
AND MORE PERSISTENT...TEMPS MAY NOT FALL THAT LOW. IN GENERAL...MOST
OF THE W HALF OF UPPER MI WILL SEE MINS IN THE -10F TO -20F RANGE
WITH WIND CHILLS FALLING TO -30 TO -45F. WITH THE CORE OF THE COLD
OVER THE AREA MON...EXPECT INTERIOR W LOCATIONS TO FAIL TO RISE
ABOVE -10F. ONLY AREAS TO GET JUST ABOVE 0F WILL BE OVER THE E.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 515 PM EST SUN JAN 5 2014
.MONDAY NIGHT INTO TUESDAY...W TO WNW LOW LEVEL WINDS WILL CONTINUE
BETWEEN LOW PRES LIFTING NNE INTO HUDSON BAY AND ARCTIC HIGH PRES
BUILDING FROM THE NRN PLAINS TO THE UPPER MS VALLEY. 850 MB TEMPS
WILL GRADUALLY MODERATE FROM THE -25C TO -30C RANGE TO -17C TO -22C
FROM 00Z/TUE TO 00Z/WED. HOWEVER...SFC TEMPS WILL CLIMB ONLY
SLIGHTLY. WINDS WILL ALSO DIMINISH TO AROUND 10 MPH BY TUE MORNING.
HOWEVER...WITH TEMPS AGAIN FALLING INTO THE -12 TO -25 RANGE...WIND
CHILL VALUES OF -30 TO -45 WILL REMAIN IN THE WARNING CATEGORY OVER
MOST OF THE CWA. LES WILL PERSIST FOR THE KEWEENAW AND THE NE CWA(E
OF MUNISING). THE HIGHER RES MODELS SUGGEST THAT LOW LEVEL CONV OVER
THE WRN LAKE MAY BOOST SNOWFALL RATES INTO THE KEWEENAW(NEAR OR JUST
SOUTH OF HOUGHTON) AND NEAR THE PICTURED ROCKS AND GRAND MARAIS.
HOWEVER...WITH THE VERY COLD AIR AND NO DGZ AVAILABLE...SLR VALUES
WILL REMAIN LOW AND LIMIT SNOW ACCUMULATIONS TO THE 1 TO 3 INCH PER
12 HOUR WEST AND POSSIBLY 2 TO 4 INCHES EAST.
TUE NIGHT AND WED...WRLY FLOW LES WILL CONTINUE AS THE AIRMASS
MODERATES. WITH THE DGZ MOVING BACK CLOSER TO THE CONVECTIVE
LAYER...SLR VALUES WILL INCREASE. HOWEVER...THE VERY AIR UPSTREAM
WILL REMAIN UNFAVORABLE FOR MORE SIGNIFICANT LES. SO...SNOWFALL RATES
WILL GENERALLY REMAIN LIGHT...IN THE 1 TO 3 INCH RANGE...WITH THE
GREATEST AMOUNTS REMAINING OVER THE KEWEENAW AND ALONG THE SHORELINE
NEAR GRAND MARAIS. WIND CHILLS WILL ALSO NOT BE AS SEVERE AS WINDS
DIMINISH CLOSER TO 5 MPH INLAND AS TEMPS DROP INTO THE -10 TO -20
RANGE GIVING WIND CHILL VALUES FROM -20 TO -30.
THU-SUN...THE MODELS SHOW A TRANSITION TO A MORE ZONAL PATTERN WITH
SEPARATED NRN AND SRN STREAMS. AFTER BACKING WINDS TO SW WILL END THE
LES OVER THE KEWEENAW THU...MAINLY DRY WEATHER IS EXPECTED INTO THE
WEEKEND WITH MUCH MILDER CONDITIONS. HIGH TEMPS SHOULD CLIMB BACK
INTO THE UPPER 20S FRI AND TO AROUND 30 FOR THE WEEKEND. ALTHOUGH THE
00Z/05 ECMWF RUN SHOWED A MORE PHASED TROUGH BY SUN THAT BRINGS UP
ENOUGH WARM AIR AND MOISTURE FOR RAIN...THE 12Z/05 RUN FLIPPED BACK
TO A MORE SEPARATE NRN STREAM WITH THE SRN SHRTWV SLIDING INTO THE
LOWER MS VALLEY SIMILAR TO THE GFS/GEFS. HOWEVER...CONFIDENCE IN ANY
WEATHER DETAILS BEYOND THE MILDER AIR FOR THE WEEKEND REMAINS LOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1234 AM EST MON JAN 6 2014
EXTREME COLD AIRMASS MOVING ACROSS THE UPPER GREAT LAKES WILL ALLOW
FOR LAKE EFFECT SNOW SHOWERS TO CONTINUE THROUGH THE PERIOD. KCMX
WILL LIKELY SEE LIGHT SNOW THROUGH THE PERIOD. DUE TO THE FINE SNOW
FLAKES AND BLOWING SNOW UNDER THE ARCTIC AIRMASS...EXPECT CONDITIONS
TO REMAIN IFR TONIGHT...THEN DETERIORATE INTO LIFR CONDITIONS ON
MONDAY AS THE FLOW BECOMES MORE WESTERLY AND THE POLAR VORTEX MOVES
OVERHEAD. KIWD WILL ALSO SEE FAIRLY PERSISTENT LIGHT SNOW AND BLSN
TONIGHT WITH IFR VSBYS. HOWEVER...AS THE FLOW BECOMES MORE WESTERLY
ON MONDAY EXPECT THE SNOW TO DIMINISH AND VSBYS TO IMPROVE BY MON
EVENING. AT KSAW...SOME LIGHT SNOW/FLURRIES TONIGHT INTO MONDAY
MORNING WILL LIKELY YIELD MVFR CONDITIONS...BUT THE EXPECTATION IS
THAT WHEN THE SURFACE FLOW BECOMES MORE W-NW ON MONDAY THAT VFR
CONDITIONS WILL DEVELOP.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 515 PM EST SUN JAN 5 2014
PRES GRADIENT WILL SLOWLY INCREASE TONIGHT THRU MON...RESULTING IN
AN INCREASE IN WINDS. LOOKS LIKE 35KT GALES WILL DEVELOP OVER
PORTIONS OF ERN LAKE SUPERIOR LATE TONIGHT OR MON MORNING...AIDED BY
LAND BREEZE CONVERGENCE. AS PRES GRADIENT TIGHTENS A LITTLE MORE...
WILL NEED TO WATCH FOR AN EXPANSION OF GALES TO MORE OF CNTRL/ERN
LAKE SUPERIOR MON NIGHT/TUE. WITH VERY COLD AIR MASS OVER THE AREA
FOR THE NEXT COUPLE OF DAYS...WINDS/WAVES WILL LEAD TO HEAVY
FREEZING SPRAY OVER MUCH OF LAKE SUPERIOR. WINDS WILL DIMINISH
DURING THE MIDWEEK PERIOD AS THE COLD EASES AND HIGH PRES MOVES
ACROSS THE GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL WARNING UNTIL 11 AM EST /10 AM CST/ TUESDAY FOR
MIZ001>005-009>013-084.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ006-
007-014-085.
WIND CHILL WARNING FROM 7 PM THIS EVENING TO 11 AM EST TUESDAY
FOR MIZ006-007-014-085.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ WEDNESDAY
FOR LSZ162-243>245-248>251-263>267.
GALE WARNING FROM 7 AM THIS MORNING TO 1 AM EST WEDNESDAY FOR
LSZ265-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLB
AVIATION...MRD
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1034 PM CST SUN JAN 5 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 305 PM CST SUN JAN 5 2014
NORTHWEST WINDS HAVE INCREASED SUBSTANTIALLY ACROSS WEST CENTRAL
THROUGH SOUTH CENTRAL MN THIS AFTERNOON WITH 20-25 KNOTS COMMON.
THIS IS OCCURRING AS THE CORE OF THE ARCTIC AIR ARRIVES ALONG WITH
THE PRESSURE GRADIENT TIGHTENING BETWEEN A LOW PRESSURE STORM SYSTEM
MOVING THROUGH THE OHIO VALLEY AND A 1053MB HIGH OVER MONTANA.
WEB CAMS ARE SHOWING BLOWING SNOW WITH 1 TO 2 MILE VISIBILITY IN
THE AFOREMENTIONED AREAS. THE BLOWING SNOW WILL CONTINUE THROUGH
THE EVENING ADDING ANOTHER ELEMENT OF DANGER TO THE ALREADY LOW
WINDS CHILLS OF -40 TO -45 CURRENTLY IN PLACE. SATELLITE IMAGERY
SHOWS SOME NICE CONVECTIVE ROLLS AS WELL IN THE MN RIVER VALLEY WITH
THE RAP INDICATING LOW LEVEL LAPSE RATES EXCEEDING 8 DEG C/KM.
LITTLE DEVIATION TO THE FORECAST LOWS/HIGHS FOR TONIGHT AND
MONDAY AS THE CORE OF THE ARCTIC VORTEX SWINGS THROUGH. MUCH OF
CENTRAL MN AND ALONG HIGHWAY 8 IN WEST CENTRAL WI EXPECTED TO
REACH -30 TO -35 WITH -25 TO -30 OVER THE REMAINDER OF THE FA.
HIGHS ON MONDAY PROGGED TO BE IN THE -13 TO -19 RANGE FROM SOUTH
TO NORTH. WIND CHILL VALUES OVERNIGHT AND MONDAY MORNING FROM -50
TO -65 WITH -40 TO -50 FOR MONDAY AFTERNOON.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 305 PM CST SUN JAN 5 2014
THE MAIN WX DISCUSSION IS THAT THE CORE OF THE COLDEST AIR WILL HAVE
MOVED OUT OF THE REGION BY MONDAY NIGHT WITH ONLY RESIDUAL AFFECTS
BASED ON WIND SPDS AND TEMPS STILL IN THE TEENS AND 20S BLW ZERO
THRU TUESDAY MORNING. AS HIGH PRESSURE MOVES OVERHEAD TUESDAY
NIGHT/WEDNESDAY...THE AFFECTS OF RADIATIONAL COOLING MAY AID IN SOME
LOWER TEMPS THAN CURRENTLY FORECAST. BASED ON CURRENT MODEL TRENDS
NEAR -20F IN THE NORTHERN CWA...TO THE SINGLE DIGITS BLW ZERO IN THE
SOUTHERN CWA SEEMS REASONABLE AT THIS TIME.
AFTER WEDNESDAY...THE JET STREAM WILL MOVE NORTH WITH A MORE ZONAL
FLOW DEVELOPING BY THE END OF THE WEEK. THIS WILL LEAD TO MUCH
WARMER TEMPS BY FRI/SAT/SUN WITH ABV NORMAL READINGS ALMOST LIKELY.
MODELS ARE STILL HAVING TROUBLE HANDLING THE SPLIT FLOW REGIME.
BASICALLY FOR OUR REGION IT MEANS THAT UNCERTAINTY EXISTS AS MODELS
ARE TRYING TO HOLD ONTO THE SOUTHERN JET AS THE MOST ACTIVE WX IN
THE NEXT 7 DAYS. CONFIDENCE WILL REMAIN LOW UNTIL MODELS HAVE A
BETTER HANDLE ON THE SOUTHERN JET STREAM STORM SYSTEM THAT WILL
AFFECT THE SOUTHERN U.S. NEXT WEEKEND. AS FOR OUR AREA...MAINLY DRY
WX WILL CONTINUE WITH A MUCH ANTICIPATED WARMING TREND AT LEAST IN
THE SHORT TERM AFTER WEDNESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1009 PM CST SUN JAN 5 2014
COLD CORE TROUGH CONTINUES TO WORK EAST ACROSS MINNESOTA THIS
EVENING. THE BACK EDGE OF THE H7 TROUGH MAY BE EXITING INTO WI
NOW...AND MAY BE ASSOCIATED WITH THE REDEVELOPMENT OF SOME LOWER
MID LEVEL CLOUDS THERE. FURTHER UPSTREAM...APPEARS ANOTHER SHORT
WAVE DROPPING ALMOST DIRECTLY SOUTH OVER NORTH DAKOTA PER WATER
VAPOR IMAGERY. SOME LAYERED CLOUDS TRYING TO DEVELOP AHEAD OF
THAT ACROSS NORTHWEST MN THIS EVENING. THIS MAY SPREAD SOUTHEAST
DURING THE NIGHT. WILL HAVE TO INCLUDE SOME CLOUD ACROSS MOST
TAFS. WILL TRY AND CONTINUE THE VFR TREND INTO THE EARLY MORNING
HOURS. THEN WITH THE ARCTIC AIRMASS IN PLACE...WE MAY STILL
DEVELOP SOME MVFR STRATUS IN IC/IF BUT CONFIDENCE IS LOW ON HOW
WIDESPREAD THIS WILL BECOME. WILL HAVE TO MONTIOR THIS FOR NEXT
TAF ISSUANCE. NORTHWEST WINDS WILL BE GUSTY THROUGH THE DAY...AND
DIMINISH AROUND 07.00Z WITH CONTINUATION VFR CONDITIONS.
KMSP...BACK EDGE OF ANOTHER SHOT OF CLOUDS EXITING INTO WISCONSIN
THIS EVENING. WILL HAVE TO WAIT UNTIL NEXT AREA MOVES IN FROM THE
NORTHWEST ASSOCIATED WITH NEXT SHORT WAVE. WILL CONTINUE VFR TREND
HOWEVER FOR NOW. MAY SEE SOME IC/IF CONDITIONS DEVELOP AROUND
SUNRISE...BUT CONFIDENCE IS LOW ON OVERALL COVERAGE OF THIS. GUSTY
NORTHWEST WINDS SHOULD DIMINISH LATE TONIGHT AND INCREASE INTO
MONDAY BEFORE RELAXING BY MONDAY EVENING. REMAINING VFR MONDAY
NIGHT.
/OUTLOOK FOR KMSP/
TUE...VFR. W WINDS 5-10 KT.
WED...VFR. WINDS NEAR CALM.
THU...VFR. WINDS SE-S 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WIND CHILL WARNING UNTIL NOON CST TUESDAY FOR MNZ041>045-047>070-
073>078-082>085-091>093.
WI...WIND CHILL WARNING UNTIL NOON CST TUESDAY FOR WIZ014>016-023>028.
&&
$$
SHORT TERM...RAH
LONG TERM...JLT
AVIATION...DWE
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
258 AM CST MON JAN 6 2014
.DISCUSSION...
CENTER OF ARCTIC HIGH PRESSURE HAD SHIFTED SOUTH OF THE AREA AT
08Z OVER OKLAHOMA WITH SURFACE GRADIENT WEAKENING OVER NEBRASKA.
AS A RESULT SURFACE WINDS BECOMING MORE VARIABLE EARLY THIS
MORNING WITH REGARD TO SPEED. SEVERAL SITES REPORTING LESS THAN
10 KTS AT 08Z. WIND CHILL VALUES HOWEVER GENERALLY RANGE FROM -25
TO -35 ACROSS THE FORECAST AREA. RAP INDICATES SURFACE GRADIENT
MAY INCREASE AGAIN DURING THE MORNING WITH WINDS PICKING UP TO
BETWEEN 10 AND 20 KTS.
ADJUSTMENTS TO CURRENT HEADLINES MAY BE NEEDED BEFORE EXPIRATION
BUT WILL PASS THIS ON TO THE DAY SHIFT TO BETTER DELINEATE TRENDS
AND AREAL IMPACT.
TEMPERATURES ARE STILL EXPECTED TO REMAIN BELOW ZERO TODAY FROM
NORTHEAST NEBRASKA INTO SOUTHWEST IOWA WITH ONLY LOW SINGLE
DIGITS TO THE WEST OF THAT AREA. SUBZERO TEMPERATURES LIKELY TO
REMAIN ACROSS MOST OF THE AREA YET TONIGHT BUT RELATIVELY WARMER
TEMPERATURES RETURN ON TUESDAY IN ADVANCE OF A WEAK CLIPPER COMING
OUT OF THE NORTHERN ROCKIES. ANOTHER PUSH OF COLD AIR MOVES INTO
THE REGION BEHIND THIS SYSTEM TUESDAY NIGHT INTO WEDNESDAY BUT NOT
AS EXTREME AS CURRENT AIRMASS OVER THE REGION.
MODELS INDICATE LESS AMPLIFIED FLOW BY WEDNESDAY WITH SPLIT FLOW
DEVELOPING IN THE EXTENDED PORTION OF THE FORECAST. THIS IS
EXPECTED TO RESULT IN TEMPERATURES CLOSER TO NORMAL OR SLIGHTLY
ABOVE FOR EARLY JANUARY. ALTHOUGH NO MAJOR WINTER STORM SYSTEM IS
INDICATED...SHORT WAVES MOVING THROUGH THE FLOW DURING THIS TIME
MAY TRIGGER PERIODS OF LIGHT SNOW FOR PARTS OF THE AREA BUT TIMING
AND STRENGTH UNCERTAIN FOR LIMITED CONFIDENCE IN ANY MENTION
BEYOND SLIGHT POPS.
&&
.AVIATION...
06Z TAFS FOR KOMA...KOFK...KLNK
CYCLONIC FLOW AROUND THE THE GREAT LAKES LOW WILL CONTINUE TO
PROVIDE A SCT SC DECK THROUGH AT LEAST THE FIRST HALF OF THE
PERIOD. MOST OF THE TIME THE SITES WILL BE VFR...BUT A SHORT
PERIOD OF MVFR CIGS ARE POSSIBLE...ESPECIALLY AT KOFK AND KOMA.
THIS WOULD BE MOST LIKELY LATE TONIGHT AND INTO THE MORNING ON
MONDAY. OTHERWISE GUSTY NORTHWEST WINDS WILL START TO DIMINISH ON
MON AFTERNOON AND WILL EVENTUALLY GO LIGHT AND VARIABLE BY MON
EVENING.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WIND CHILL WARNING UNTIL MIDNIGHT CST TONIGHT FOR NEZ011-012-
015>018-030>034-042>045-050>053.
WIND CHILL WARNING UNTIL 6 PM CST THIS EVENING FOR NEZ065>068-
078-088>093.
IA...WIND CHILL WARNING UNTIL MIDNIGHT CST TONIGHT FOR IAZ043-055-056-
069.
WIND CHILL WARNING UNTIL 6 PM CST THIS EVENING FOR IAZ079-080-
090-091.
&&
$$
FOBERT/BOUSTEAD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
419 AM EST MON JAN 6 2014
.SYNOPSIS...
A STRONG ARCTIC COLD FRONT WILL SWEEP THROUGH THE STATE THIS MORNING.
DANGEROUSLY COLD WIND CHILL VALUES ARE EXPECTED MONDAY NIGHT
THROUGH WEDNESDAY WITH NEAR RECORD COLD TEMPERATURES. THE ARCTIC
AIR MASS WILL LIFT OUT OF THE AREA LATER THIS WEEK.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
POCKETS OF COLD AIR IN THE VALLEYS OF EASTERN PA BEGINNING TO GET
SCOURED OUT EARLY THIS AM...AS DEEP SOUTHERLY FLOW AHEAD OF
APPROACHING COLD FRONT OVERSPREADS THE AREA. 07Z MESONET STILL
SHOWING A FEW SPOTS NR 32F...SO HAVE ISSUED A SPS TO COVER
POCKETS OF LINGERING ICY PATCHES ACROSS THE SC MTNS AND SUSQ
VALLEY THRU 08Z. THE WARMER/MOIST SOUTHERLY FLOW OVERIDING SNOW
COVERED GROUND HAS RESULTED IN AREAS OF DENSE FOG ACROSS THE LOWER
SUSQ VALLEY. LATEST SREF AND RAP SUGGEST PATCHY DENSE FOG MAY
PERSIST UNTIL ARRIVAL OF ARCTIC COLD FRONT ARND DAWN.
07Z REGIONAL RADAR LOOP SHOWS BAND OF RAIN FALLING ACROSS WESTERN
PA ALONG AXIS OF LL JET/ANOMALOUS PWATS PRECEDING COLD FRONT.
THIS BAND OF RAIN WILL CROSS CENTRAL PA DURING THE EARLY AM
HOURS...EXITING THE EASTERN COUNTIES SHORTLY AFTER 12Z. REGIONAL
RADAR/SFC OBS SHOW PRECIP TURNING TO A BRIEF PERIOD OF SNOW ACROSS
OHIO...AND MDL SOUNDINGS SUGGEST A SIMILAR TRANSITION WILL OCCUR
OVR THE W MTNS BTWN 09Z-12Z. A LIGHT ACCUM OF AN INCH OR LESS
APPEARS MOST LIKELY ACROSS THE ALLEGHENY PLATEAU...WHILE
DRYING/DOWNSLOPING FLOW IS LIKELY TO RESULT IN NO ACCUMS FOR MOST
SPOTS EAST OF THE ALLEGHENIES. HAVE ISSUED A SPS TO COVER THE
LIKELIHOOD OF A FLASH FREEZE/BLACK ICE OVR THE W MTNS...WHERE
PLUMMETING TEMPS WILL LIKELY TURN ANY SLUSH TO ICE.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM TUESDAY/...
STRONG COLD ADVECTION WILL PREVAIL THROUGHOUT THE DAY BEHIND THE
FRONT...WHICH EXITS THE EAST EARLY MONDAY MORNING. FLASH FREEZES
WILL BE POSSIBLE WITH RAPIDLY PLUNGING TEMPERATURES AND WIND
CHILLS RATCHETING UP TO UNCOMFORTABLE RANGES LATE MORNING AND
AFTERNOON. TEMPS WILL FALL THROUGHOUT THE DAY...THANKS TO 850 MB
TEMPS PLUNGING TO AS LOW AS -25 TO -27C BY MONDAY EVENING.
ASTOUNDING.
WIND CHILL WATCHES UPGRADED TO WARNINGS BEGINNING MONDAY AFTERNOON
FOR THE ALLEGHENY PLATEAU. WIND CHILLS OF -25F TO AS LOW AT -35F OR
EVEN -40F WILL BE POSSIBLE FROM MONDAY EVENING THROUGH WEDNESDAY
MORNING. BRR... WIND CHILL WATCHES REMAIN IN EFFECT FARTHER EAST
ACROSS THE REMAINDER OF THE LAUREL HIGHLANDS...AND THE CENTRAL AND
NORTH CENTRAL MOUNTAINS. BY LATE AFTERNOON...TEMPS WILL BE IN THE
SINGLE DIGITS ABOVE ZERO ACROSS THE NORTHWEST MOUNTAINS...RANGING
TO THE MID TEENS CENTRAL MOUNTAINS AND TO THE MID TO UPPER 20S
SOUTHEAST.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
MAIN CHANGE WAS TO POST A LAKE SNOW ADVISORY FOR WARREN.
OFTEN WHEN THE AIRMASS IS REAL COLD...THE COLD AIR COMES
IN FROM THE SW. THIS MAY LIMIT THE LAKE EFFECT AT TIMES
ACROSS THE NW...BUT EVEN WITH THIS...THE STRONG FLOW WILL
LIKELY CARRY THE SNOW SHOWERS WELL TO THE EAST.
ALSO PUT SOME MENTION OF SNOW SHOWERS IN THE LAUREL HIGHLANDS.
HARD TO SEE HOW UPSLOPE FLOW WILL NOT RESULT IN SOME SNOW
SHOWERS...EVEN WITH THIN SC DECK.
OTHER CHANGE WAS TO CUT BACK POPS LATE IN THE WEEK. WEIGHTED
FORECAST TO WPC CHARTS.
EXPECT SOME WARM UP LATE IN THE WEEK...A LOT OF MODEL SPREAD.
PART OF THE AREA UPGRADED TO A WIND CHILL WARNING.
EARLIER DISCUSSION BELOW.
AIR MASS AS DEFINED BY 8H TEMPS COULD BE THE COLDEST THIS
REGION HAS SEEN IN 20 YEARS. BY TUES AM...THE CORE OF THE COLD
SHOULD LIE ACROSS SOUTHWEST PA...WHERE GEFS ENS MEAN 8H TEMPS FALL
TO -30C. THE FRIGID TEMPS...COMBINED WITH WGUSTS ARND 30KTS MON
NIGHT THRU TUESDAY WILL RESULT IN EXTREMELY DANGEROUS
CONDITIONS...MAKING FROSTBITE AND HYPOTHERMIA A REAL CONCERN EVEN
IF EXPOSED TO THE ELEMENTS FOR ONLY A SHORT PERIOD. HAVE EXPANDED
THE WIND CHILL WATCH EASTWARD INTO THE RIDGE/VALLEY REGION...AS
CONFIDENCE INCREASES THAT WARNING CRITERIA OF 25 BLW WILL BE
REACHED. ALTHOUGH IT APPEARS UNLIKELY WE WILL RIVAL THE MIN TEMPS
OF 1994...WIND CHILLS MAY BE AS COLD OR COLDER AS TIGHT PRES
GRADIENT CONTINUES TO BUFFET THE AREA WITH GUSTS NR 30KTS INTO TUE
EVENING.
SIG LAKE EFFECT DOES NOT APPEAR TO BE A CONCERN...AS MDL DATA
INDICATES BLYR FLOW WILL KEEP SNOW SHOWERS NORTH OF THE BORDER
MON-WED. WEDNESDAY MORNING WILL ALSO BE VERY COLD...AS WINDS
SLACKEN UPON ARRIVAL OF SFC HIGH. MODEL CONSENSUS SUPPORTS TEMPS
SLOWLY MODERATING BACK TOWARDS NORMAL BY THE SECOND HALF OF THE
WEEK. A LIGHT OVERRUNNING SNOWFALL IS POSSIBLE LATE WEEK...AS
WARMER SW FLOW TRIES TO DISLODGE LINGERING LOW LVL CHILL ACROSS
THE NORTHEAST CONUS.
&&
.AVIATION /09Z MONDAY THROUGH FRIDAY/...
A SHARP ARCTIC COLD FRONT WILL SWEEP ACROSS CENTRAL PA THROUGH
MID MORNING...WITH LLWS AS STRONG SOUTHERLY LOW LEVEL JET SHIFTS
TO THE WEST BY 14Z.
QUITE VARIABLE CONDITIONS ACROSS CENTRAL PA THIS MORNING AHEAD OF
QUICKLY APPROACHING ARCTIC FRONT. IN THE SUSQ VALLEY...REDUCTIONS
IN FOG WILL PERSIST THROUGH 12-14Z WITH POCKETS OF FZDZ. CENTRAL
TERMINALS MAY SEE CIGS LIFT BRIEFLY BEFORE SUNRISE BEFORE FALLING
BACK TO MVFR/IFR AS SOUTHERLY WIND GUSTS APPROACH 35 MPH. WESTERN
TERMINALS AND RIDGES WILL SEE SOUTHWEST WINDS GUST TO AS HIGH AS
45 KTS BETWEEN 09-11Z BEFORE FLOW TURNS WESTERLY AND CIGS LOWER
FURTHER WITH LIGHT SNOW.
BY 14Z...GUSTY WINDS WILL TURN TO THE WEST AT ALL TAF SITES AS
MUCH COLDER AIR BARRELS IN. THEN FROM LATE MORNING INTO EARLY
AFTERNOON...CIGS AND VSBYS WILL GRADUALLY LIFT AND IMPROVE OVER
THE CENTRAL AND SE...WHILE MVFR CIGS PERSIST IN WESTERN HIGHER
ELEVATIONS. AFTER THAT...PERSISTENCE WILL BE THE RULE WITH MVFR
WEST AND WINDY CONDITIONS AREAWIDE INTO TUESDAY.
OUTLOOK...
TUE...SCT SNOW SHOWERS NW. VFR ELSEWHERE. WINDY.
WED...SCT SNOW SHOWERS NW. VFR ELSEWHERE.
THU...MVFR TO IFR WITH CHC LIGHT SNOW/MIXED PRECIP LATE.
FRI...MIXED PRECIPITATION WITH IFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WIND CHILL WATCH FROM LATE TONIGHT THROUGH WEDNESDAY MORNING
FOR PAZ012-018-019-025>027-034-035-037-041-042-045-046.
WIND CHILL WARNING FROM 3 PM THIS AFTERNOON TO NOON EST
WEDNESDAY FOR PAZ004>006-010-011-017-024-033.
DENSE FOG ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
PAZ036-056>059-063>066.
LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST
WEDNESDAY FOR PAZ004.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...DANGELO/FITZGERALD
SHORT TERM...DEVOIR
LONG TERM...FITZGERALD/MARTIN
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
203 AM EST MON JAN 6 2014
.SYNOPSIS...
A STRONG ARCTIC COLD FRONT WILL SWEEP THROUGH THE STATE THIS MORNING.
DANGEROUSLY COLD WIND CHILL VALUES ARE EXPECTED MONDAY NIGHT
THROUGH WEDNESDAY WITH NEAR RECORD COLD TEMPERATURES. THE ARCTIC
AIR MASS WILL LIFT OUT OF THE AREA LATER THIS WEEK.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
POCKETS OF COLD AIR IN THE VALLEYS OF EASTERN PA BEGINNING TO GET
SCOURED OUT EARLY THIS AM...AS DEEP SOUTHERLY FLOW AHEAD OF
APPROACHING COLD FRONT OVERSPREADS THE AREA. 07Z MESONET STILL
SHOWING A FEW SPOTS NR 32F...SO HAVE ISSUED A SPS TO COVER
POCKETS OF LINGERING ICY PATCHES ACROSS THE SC MTNS AND SUSQ
VALLEY THRU 08Z. THE WARMER/MOIST SOUTHERLY FLOW OVERIDING SNOW
COVERED GROUND HAS RESULTED IN AREAS OF DENSE FOG ACROSS THE LOWER
SUSQ VALLEY. LATEST SREF AND RAP SUGGEST PATCHY DENSE FOG MAY
PERSIST UNTIL ARRIVAL OF ARCTIC COLD FRONT ARND DAWN.
07Z REGIONAL RADAR LOOP SHOWS BAND OF RAIN FALLING ACROSS WESTERN
PA ALONG AXIS OF LL JET/ANOMALOUS PWATS PRECEDING COLD FRONT.
THIS BAND OF RAIN WILL CROSS CENTRAL PA DURING THE EARLY AM
HOURS...EXITING THE EASTERN COUNTIES SHORTLY AFTER 12Z. REGIONAL
RADAR/SFC OBS SHOW PRECIP TURNING TO A BRIEF PERIOD OF SNOW ACROSS
OHIO...AND MDL SOUNDINGS SUGGEST A SIMILAR TRANSITION WILL OCCUR
OVR THE W MTNS BTWN 09Z-12Z. A LIGHT ACCUM OF AN INCH OR LESS
APPEARS MOST LIKELY ACROSS THE ALLEGHENY PLATEAU...WHILE
DRYING/DOWNSLOPING FLOW IS LIKELY TO RESULT IN NO ACCUMS FOR MOST
SPOTS EAST OF THE ALLEGHENIES. HAVE ISSUED A SPS TO COVER THE
LIKELIHOOD OF A FLASH FREEZE/BLACK ICE OVR THE W MTNS...WHERE
PLUMMETING TEMPS WILL LIKELY TURN ANY SLUSH TO ICE.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM TUESDAY/...
STRONG COLD ADVECTION WILL PREVAIL THROUGHOUT THE DAY BEHIND THE
FRONT...WHICH EXITS THE EAST EARLY MONDAY MORNING. FLASH FREEZES
WILL BE POSSIBLE WITH RAPIDLY PLUNGING TEMPERATURES AND WIND
CHILLS RATCHETING UP TO UNCOMFORTABLE RANGES LATE MORNING AND
AFTERNOON. TEMPS WILL FALL THROUGHOUT THE DAY...THANKS TO 850 MB
TEMPS PLUNGING TO AS LOW AS -25 TO -27C BY MONDAY EVENING.
ASTOUNDING.
WIND CHILL WATCHES UPGRADED TO WARNINGS BEGINNING MONDAY AFTERNOON
FOR THE ALLEGHENY PLATEAU. WIND CHILLS OF -25F TO AS LOW AT -35F OR
EVEN -40F WILL BE POSSIBLE FROM MONDAY EVENING THROUGH WEDNESDAY
MORNING. BRR... WIND CHILL WATCHES REMAIN IN EFFECT FARTHER EAST
ACROSS THE REMAINDER OF THE LAUREL HIGHLANDS...AND THE CENTRAL AND
NORTH CENTRAL MOUNTAINS. BY LATE AFTERNOON...TEMPS WILL BE IN THE
SINGLE DIGITS ABOVE ZERO ACROSS THE NORTHWEST MOUNTAINS...RANGING
TO THE MID TEENS CENTRAL MOUNTAINS AND TO THE MID TO UPPER 20S
SOUTHEAST.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
MAIN CHANGE WAS TO POST A LAKE SNOW ADVISORY FOR WARREN.
OFTEN WHEN THE AIRMASS IS REAL COLD...THE COLD AIR COMES
IN FROM THE SW. THIS MAY LIMIT THE LAKE EFFECT AT TIMES
ACROSS THE NW...BUT EVEN WITH THIS...THE STRONG FLOW WILL
LIKELY CARRY THE SNOW SHOWERS WELL TO THE EAST.
ALSO PUT SOME MENTION OF SNOW SHOWERS IN THE LAUREL HIGHLANDS.
HARD TO SEE HOW UPSLOPE FLOW WILL NOT RESULT IN SOME SNOW
SHOWERS...EVEN WITH THIN SC DECK.
OTHER CHANGE WAS TO CUT BACK POPS LATE IN THE WEEK. WEIGHTED
FORECAST TO WPC CHARTS.
EXPECT SOME WARM UP LATE IN THE WEEK...A LOT OF MODEL SPREAD.
PART OF THE AREA UPGRADED TO A WIND CHILL WARNING.
EARLIER DISCUSSION BELOW.
AIR MASS AS DEFINED BY 8H TEMPS COULD BE THE COLDEST THIS
REGION HAS SEEN IN 20 YEARS. BY TUES AM...THE CORE OF THE COLD
SHOULD LIE ACROSS SOUTHWEST PA...WHERE GEFS ENS MEAN 8H TEMPS FALL
TO -30C. THE FRIGID TEMPS...COMBINED WITH WGUSTS ARND 30KTS MON
NIGHT THRU TUESDAY WILL RESULT IN EXTREMELY DANGEROUS
CONDITIONS...MAKING FROSTBITE AND HYPOTHERMIA A REAL CONCERN EVEN
IF EXPOSED TO THE ELEMENTS FOR ONLY A SHORT PERIOD. HAVE EXPANDED
THE WIND CHILL WATCH EASTWARD INTO THE RIDGE/VALLEY REGION...AS
CONFIDENCE INCREASES THAT WARNING CRITERIA OF 25 BLW WILL BE
REACHED. ALTHOUGH IT APPEARS UNLIKELY WE WILL RIVAL THE MIN TEMPS
OF 1994...WIND CHILLS MAY BE AS COLD OR COLDER AS TIGHT PRES
GRADIENT CONTINUES TO BUFFET THE AREA WITH GUSTS NR 30KTS INTO TUE
EVENING.
SIG LAKE EFFECT DOES NOT APPEAR TO BE A CONCERN...AS MDL DATA
INDICATES BLYR FLOW WILL KEEP SNOW SHOWERS NORTH OF THE BORDER
MON-WED. WEDNESDAY MORNING WILL ALSO BE VERY COLD...AS WINDS
SLACKEN UPON ARRIVAL OF SFC HIGH. MODEL CONSENSUS SUPPORTS TEMPS
SLOWLY MODERATING BACK TOWARDS NORMAL BY THE SECOND HALF OF THE
WEEK. A LIGHT OVERRUNNING SNOWFALL IS POSSIBLE LATE WEEK...AS
WARMER SW FLOW TRIES TO DISLODGE LINGERING LOW LVL CHILL ACROSS
THE NORTHEAST CONUS.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
SOUTHERLY FLOW CONTINUES AS PRECIPITATION CHANGES OVER TO RAIN AS
THE CURRENT TEMPERATURES ARE GENERALLY SLIGHTLY ABOVE FREEZING.
THERE REMAINS SOME HOLD OUTS THROUGH THE SOUTHEAST WHERE
INTERMITTENT PRECIPTIATION COULD COME DOWN AS -FZRA BRIEFLY. THIS
P TYPE CHANGE SHOULD CONTINUE OVERNIGHT. LIFR AND LOWER CONDITIONS
WILL BE WIDESPREAD FOR ALL TAF SITES EXCEPT IPT...WHERE RAIN IS
FALLING. THOSE SITES SHOULD GO TO IFR AND LOWER RESTRICTIONS AT
TIMES BETWEEN 06 AND 12Z.
A STARK FRONT WILL MOVE THROUGH THE REGION TOMORROW
MORNING...BRINGING A WIND SHIFT WITH GUSTY WINDS OUT OF THE WEST
BY 12Z. GUSTY WINDS HAVE CURRENTLY ENTRENCHED THEMSELVES AT THE HIGHER
ELEVATIONS DUE TO THE STRONG SOUTHERLY FLOW OUT AHEAD OF THIS
DEEPENING TROUGH. CIGS AND VSBYS WILL CONTINUE IFR AND LOWER
RESTRICTIONS AS SYNOPTIC LIFT INCREASES WITH ARRIVAL OF THE
AFOREMENTIONED DEEPENING LOW PRESSURE FROM THE OHIO VALLEY. THE
WARMER AIR MOVING OVER THE SNOWPACK IN THE EAST WILL LIKELY
CONTINUE TO GENERATE AN AREA OF THICKER FOG THAT IS CURRENTLY
REDUCING VSBYS ACROSS THE LOWER SUSQ AND AOO...REDUCING VSBYS
BELOW A MILE. LLWS INCLUDED IN TAFS AS 850 MB JET INCREASES TO
40-60 KTS AND WILL CONTINUE UNTIL AROUND 12Z.
THE GUSTY RAIN SHOWERS THAT WILL LIKELY ACCOMPANY FROPA ALONG AN
AXIS OF ANOMALOUS SOUTHERLY LL JET/PWATS. ARRIVAL OF MUCH COLDER
AIR WILL TURN THE SHRA TO SHSN FROM 12Z TO 16Z. ONCE THE FRONT
EXITS...CIGSY AND VSBYS SHOULD LIFT AND IMPROVE...WITH MVFR
CONDITIONS POSSIBLE UNTIL 18Z AND MOST IF NOT ALL TAF SITES GOING
VFR BY 00Z TUESDAYE.
OUTLOOK...
MON...RESTRICTIONS IN THE MORNING...THEN IMPROVING CIGS /ESP SE
HALF/ AS STRONG WESTERLY WINDS DEVELOP.
TUE...SCT SNOW SHOWERS NW. VFR ELSEWHERE. WINDY.
WED...SCT SNOW SHOWERS NW. VFR ELSEWHERE.
THU...MVFR TO IFR WITH CHC LIGHT SNOW/MIXED PRECIP LATE.
FRI...MIXED PRECIPITATION WITH IFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WIND CHILL WATCH FROM LATE TONIGHT THROUGH WEDNESDAY MORNING
FOR PAZ012-018-019-025>027-034-035-037-041-042-045-046.
WIND CHILL WARNING FROM 3 PM THIS AFTERNOON TO NOON EST
WEDNESDAY FOR PAZ004>006-010-011-017-024-033.
DENSE FOG ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
PAZ036-056>059-063>066.
LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST
WEDNESDAY FOR PAZ004.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...DANGELO/FITZGERALD
SHORT TERM...DEVOIR
LONG TERM...FITZGERALD/MARTIN
AVIATION...DEVOIR/CERU
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1119 PM CST SUN JAN 5 2014
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.UPDATE...
ISSUED AT 554 PM CST SUN JAN 5 2014
NOT MEETING CRITERIA YET...BUT WL LET THE WIND CHILL WARNING GO
INTO EFFECT AS SCHEDULED AT 600 PM.
SUSPECT OUR OVERNIGHT MINS MIGHT BE A BIT LOW AND WIND MIGHT BE A
LITTLE HIGH...SO WIND CHILLS MAY NOT BE QUITE AS LOW AS WE HAVE IN
THE FCST. BUT THEY SHOULD STILL MAKE WARNING CRITERIA.
STILL WAITING FOR THE FRONTAL WAVE TO LIFT OFF TO THE NE FOR THE
CORE OF THE COLD TO OVERSPREAD THE AREA. WL SEE HOW THINGS EVOLVE
DURING THE NEXT COUPLE HOURS...AND MAY MAKE SOME SML ADJUSTMENTS
TO THE FCST A LITTLE LATER THIS EVENING.
&&
.SHORT TERM...TONIGHT AND MONDAY
ISSUED AT 204 PM CST SUN JAN 5 2014
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A STRENGTHENING
AREA OF LOW PRESSURE MOVING NORTHEAST OVER THE OHIO VALLEY. A WIDE
SWATH OF HEAVY SNOW IS IMPACTING ST LOUIS TO THE THUMB OF MICHIGAN JUST
NORTH OF THE SURFACE LOW TRACK...AND IS NOT SHOWING ANY SIGNS OF
LIFTING INTO EAST-CENTRAL WISCONSIN. ALTOSTRATUS ON THE NORTHERN
PERIPHERY OF THIS SYSTEM IS MOVING ACROSS MUCH OF CENTRAL AND NORTHEAST
WISCONSIN AND IS PREVENTING ANY SUNSHINE TO OFFSET THE COLD
TEMPERATURES. READINGS THIS AFTERNOON REMAIN BELOW ZERO WEST OF A
WAUTOMA TO IRON MOUNTAIN LINE...WHERE WIND CHILLS ARE NEAR OR BELOW
WIND CHILL ADVISORY CRITERIA (-20F). FARTHER WEST...A LOBE OF THE
POLAR VORTEX IS DROPPING SOUTHEAST OVER THE DAKOTAS WHERE TEMPS ARE
IN THE TEENS BELOW ZERO WITH WINDS GUSTING OVER 40 KTS. ALSO SEEING
LOWER VSBYS WITHIN SOME CLOUD COVER IN THIS REGION...BUT THINK MUCH
OF THESE OBS CAN BE ATTRIBUTED TO BLOWING SNOW. AS THE POLAR VORTEX
AND ASSOCIATED ARCTIC AIR MOVES ACROSS THE REGION...LIGHT SNOW
CHANCES AND WIND CHILL HEADLINES ARE THE MAIN FORECAST CONCERNS.
TONIGHT...THE LOW PRESSURE SYSTEM WILL MOVE FROM THE OHIO VALLEY TO THE
EASTERN GREAT LAKES THIS EVENING. CYCLONIC FLOW AROUND THE LOW WILL
DELAY THE BITTERLY COLD ARCTIC AIR FROM REACHING NORTHEAST WISCONSIN
UNTIL LATE IN THE EVENING OR EARLY OVERNIGHT. OTHERWISE A LOBE OF
THE POLAR VORTEX WILL SWING EAST FROM THE NORTHERN MISSISSIPPI
VALLEY TO NORTHEAST WISCONSIN. AS THIS OCCURS...SHOULD SEE AN AREA
OF LOW AND MID CLOUDS MOVE EAST OVER THE FORECAST AREA. SINCE THE
LOWER VSBYS OVER THE DAKOTAS HAS THE LOOK OF BLOWING SNOW...WILL
REMOVE THE FLURRY MENTION AFTER MIDNIGHT. HOWEVER...MODELS TRY TO
RETURN SOME MOISTURE FROM THE SOUTH AHEAD OF THE SHORTWAVE LOBE AND
PRODUCE LIGHT SNOW OR FLURRIES ALONG THE LAKE MICHIGAN SHORELINE
LATE TONIGHT. THIS POSSIBILITY STILL LOOKS REASONABLE AND WILL
LEAVE IN THE FORECAST. OTHERWISE...THE MAIN STORY WILL BE THE
ADVECTION OF THE COLDEST AIR THE REGION HAS OBSERVED IN YEARS.
850MB TEMPS WILL FALL INTO THE -25C TO -35C RANGE MY 12Z MON WHICH
WILL BRING IN SURFACE TEMPS FROM 30 BELOW OVER NORTH-CENTRAL
WISCONSIN TO ABOUT 15 BELOW AT THE LAKE MICHIGAN SHORELINE.
COMBINED WITH WINDS GUSTING TO 25 TO 30 MPH...PROJECTED WIND CHILLS
WILL FALL INTO THE 40 TO 55 DEGREES BELOW ZERO RANGE. EASTERN
SECTIONS MAY NOT REACH WIND CHILL WARNING CRITERIA UNTIL AFTER
MIDNIGHT...BUT THEY WILL BE FALLING RAPIDLY THROUGH THE EVENING...SO
WILL LEAVE THE WARNING START TIMES ALONE TO INCLUDE THE ADVISORY
RAMP UP TIME.
MONDAY...THE POLAR VORTEX WILL BE EXITING NORTHEAST WISCONSIN EARLY
IN THE MORNING AND WILL LEAVE A SMALL CHANCE OVER DOOR COUNTY TO
ACCOUNT FOR THAT. SHOULD SEE A PERIOD OF DECREASING CLOUDS UNTIL
MID AND HIGH CLOUDS SLIDE IN FROM THE NORTH DURING THE AFTERNOON.
NOT SURE HOW MUCH OF THESE CLOUDS WILL HOLD TOGETHER...SO WILL KEEP
SKIES IN THE PARTLY CLOUDY RANGE. ARCTIC HIGH PRESSURE WILL SLIDE
SOUTHEAST TOWARDS THE CENTRAL PLAINS WHICH SHOULD KEEP A TIGHT
PRESSURE GRADIENT IN PLACE. COMBINED WITH TEMPERATURES IN THE
NEGATIVE TEENS BELOW ZERO FOR HIGHS...WIND CHILLS WILL REMAIN IN THE
35 TO 45 DEGREES BELOW ZERO RANGE. WIND CHILL WARNINGS WILL
CONTINUE AS A RESULT.
.LONG TERM...MONDAY NIGHT THROUGH SUNDAY
ISSUED AT 204 PM CST SUN JAN 5 2014
THE BITTER COLD REGIME OF ARCTIC AIR WILL STUBBORNLY DIMINISH
THIS WEEK AS THE UPPER FLOW TURNS MORE ZONAL WITH THE INTRODUCTION
OF WESTERLY PACIFIC FLOW AND MILDER CONDITIONS BY NEXT WEEKEND.
EVEN THOUGH THE CENTER OF THE POLAR VORTEX IS LIFTING NORTHEAST OF
THE AREA MONDAY NIGHT INTO EARLY TUESDAY...BITTER COLD AIR MASS
LEFT IN ITS WAKE COMBINED WITH WEST WINDS 10 TO 20 MPH WILL
CONTINUE TO PRODUCE WARNING WIND CHILL NUMBERS THROUGH A GOOD
PORTION OF TUESDAY BEFORE SUBSIDING TO ADVISORY CRITERIA IN THE
AFTERNOON.
HIGH PRESSURE RIDGE BEGINS TO SETTLES OVER THE AREA LATER TUESDAY
AFTERNOON INTO TUESDAY NIGHT. EVEN THOUGH 850 TEMPS BEGIN TO
MODIFY...EXPECTED CLEAR SKIES AND LIGHT WINDS WILL ALLOW TEMPS TO
PLUMMET WELL BELOW ZERO AGAIN. DEPENDING ON WINDS...PARTS OF THE
THE AREA MAY STILL WARRANT WIND CHILL ADVISORY HEADLINES. THE COLD
HIGH PRESSURE REMAINS SETTLED OVER THE REGION WEDNESDAY NIGHT AND
THURSDAY FOR CONTINUED BELOW NORMAL SUB ZERO TEMPERATURES. A WEAK
SYSTEM IS PROGGED TO PASS SOUTH OF THE AREA WEDNESDAY NIGHT AND
THURSDAY...HAS TRENDED SOUTH LEAVING THE AREA MORE IN THE COLD
AIR MASS.
WAA PATTERN BEGINS IN EARNEST LATER THURSDAY INTO FRIDAY WITH
TEMPERATURES APPROACHING THE FREEZING MARK FOR THE WEEKEND. DUE
TO THE ZONAL FLOW...MODELS ARE PRODUCING DIFFERENT SOLUTIONS WITH
TIMING OF WEAK SHORT WAVES PASSING OVER OR NEAR THE GREAT LAKES
REGION FRIDAY INTO SUNDAY. USUALLY THE PACIFIC SYSTEMS ARE ON THE
DRY SIDE BUT WITH H850 TEMPERATURES ABOVE ZERO THIS WEEKEND...PCPN
TYPE ISSUES WILL INCREASE.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1118 PM CST SUN JAN 5 2014
ARCTIC AIR BECOMING ESTABLISHED ACRS THE AREA. COULD SEE SOME SCT
MVFR CIGS AS DEEP VORTEX SLIDES ACRS THE AREA LATE TNGT/EARLY MON.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
WIND CHILL WARNING UNTIL NOON CST TUESDAY FOR WIZ005-010>013-
018>022-030-031-035>040-045-048>050-073-074.
&&
$$
UPDATE.........SKOWRONSKI
SHORT TERM.....MPC
LONG TERM......TDH
AVIATION.......SKOWRONSKI
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
329 AM MST MON JAN 6 2014
.SHORT TERM...STRONG UPPER LEVEL JET IS MOVING OVERHEAD AT THIS
TIME CREATING SOME LOCALIZED VERY WINDY CONDITIONS IN THE HIGH
ELEVATIONS AND PARTS OF SOUTH PARK IN THE LEE OF THE MOSQUITO
RANGE. THERE IS LIKELY SOME BLOWING SNOW IN THESE AREAS AS WELL.
AS THE JET PUSHES EASTWARD WITH THE UPPER RIDGE COMING OUR WAY
THESE VERY STRONG WINDS SHOULD SETTLE DOWN BUT IT WILL REMAIN
RELATIVELY WINDY UP HIGH THROUGH THE PERIOD. WITH THE FLOW ALOFT
BECOMING A BIT MORE WESTERLY MOUNTAIN WAVE ACTIVITY WILL BRING
GUSTY WINDS TO SOME FOOTHILL LOCATIONS AS WELL AS AREAS RIGHT UP
AGAINST THE FOOTHILLS LATER IN THE DAY. THE HRRR SEEMS TO HAVE A
DECENT GRASP ON THIS SITUATION. ANY SPOTS THAT SEE THE GUSTY WINDS
WILL ALSO BE PRONE TO BLOWING AND DRIFTING SNOW AND ASSOCIATED
LOWERED VISIBILITIES. THERE WILL BE A FEW SNOW SHOWERS OVER THE
HIGHER MOUNTAINS THIS MORNING ALONG WITH SOME PATCHY FOG OVER THE
PLAINS. ASIDE FROM THESE PHENOMENA WEATHER NIL. WILL LET THE WIND
CHILL ADVISORY GO AS IS...EXPIRING AT 0800 MST. HIGH TEMPERATURES
WILL REMAIN BELOW NORMAL TODAY BUT WILL PROBABLY BE SOME 15 TO 20
DEGREES ABOVE THOSE EXPERIENCED SUNDAY. MINIMA TONIGHT WILL ALSO
BE QUITE A BIT WARMER THAN WHAT IS OCCURRING PRESENTLY. PLENTY OF
SUNSHINE TODAY AND GENERALLY CLEAR SKIES TONIGHT ASIDE FROM THE
WAVE CLOUDS SHOWN IN THE CIRA SYNTHETIC SATELLITE IMAGERY. THESE
BECOME RATHER EXTENSIVE OVER THE FOOTHILLS BY 12Z TUESDAY.
.LONG TERM...MODELS HAVE MODERATE WEST-NORTHWESTERLY FLOW ALOFT FOR
THE FORECAST AREA TUESDAY THROUGH WEDNESDAY NIGHT. A WEAK TROUGH
MOVES ACROSS IN THE FLOW TUESDAY AFTERNOON AND EVENING. THEN
ANOTHER WEAK ONE LATER ON WEDNESDAY. NOTHING SIGNIFICANT...PERHAPS
A SPOT OF SNOW FOR THE MOUNTAINS. THERE IS ASCENT PROGGED
ACCORDING TO THE QG VERTICAL VELOCITY FIELDS FOR THE CWA ON
TUESDAY...THEN DOWNWARD MOTION TUESDAY NIGHT. WEDNESDAY`S SYNOPTIC
SCALE ENERGY IS PRETTY BENIGN. SOME OF THE MODELS SHOW WEAK LOW
LEVEL UPSLOPE FOR THE PLAINS TUESDAY AFTERNOON AND EVENING.
WEDNESDAY`S WINDS LOOK PRETTY WEAK...WITH MAYBE SOME DOWNSLOPING
TO ENHANCE THE NORMAL DRAINAGE PATTERNS WEDNESDAY NIGHT. FOR
MOISTURE...MODELS SHOW QUITE A BIT IN THE MID AND UPPER LEVELS
FROM MIDDAY TUESDAY THROUGH WEDNEDAY AFTERNOON. THE MOISTURE IS
PRETTY DEEP OVER THE MOUNTAINS TUESDAY NIGHT WELL INTO WEDNESDAY.
THIS MORE SO ON THE GFS. MODELS HAVE LIMITED MEASURABLE SNOWFALL
OVER THE MOUNTAINS TUESDAY EVENING INTO WEDNESDAY EVENING
ACCORDING TO THE QPF FIELDS. FOR POPS...WILL KEEP IN OR GO WITH
20-50%S IN THE MOUNTAINS AND HIGH VALLEYS...SAVE PARK COUNTY
...FROM TUESDAY NIGHT THROUGH WEDNESDAY EVENING. WILL DECREASE
MOUNTAIN POPS WEDNESDAY NIGHT AFTER MIDNIGHT. NO POPS FOR THE
PLAINS OR FOOTHILLS. FOR TEMPERATURES...TUESDAY`S HIGHS ARE
PROGGED TO 6-11 C WARMER THAN TODAY`S. WEDNESDAY`S COOL DOWN A
BIT...SOME 2.0-3.5 C FROM TUESDAY`S. FOR THE LATER DAYS...
THURSDAY THROUGH SUNDAY...MODELS KEEP MORE OF THE SAME GOING. THEY
HAVE A WEAK UPPER TROUGH MOVE ACROSS THURSDAY MORNING...BUT A
STRONGER ONE ON FRIDAY...WHICH THE ECMWF IS A PERIOD QUICKER WITH.
THERE ARE STRONG NORTH TO NORTHWEST UPPER LEVEL WINDS BEHIND THE
TROUGH...AGAIN WHICH THE ECMWF IS EARLIER WITH. BY SUNDAY...BOTH
MODELS ARE SHOWING A MORE SIGNIFICANT UPPER TROUGH GETTING INTO
COLORADO. IT BEARS WATCHING. WILL HAVE "CHANCE" POPS IN THE
MOUNTAINS FRIDAY INTO FRIDAY NIGHT. WILL GO SOME LIMITED POPS FOR
ALL THE CWA ON SUNDAY. TEMPERATURES LOOK TO HOVER NEAR NORMALS
MUCH OF THE TIME.
&&
.AVIATION...THERE MAY BE SOME PATCHES OF FOG FLOATING ABOUT UNTIL
MID MORNING WHICH COULD CREATE LIFR CONDITIONS FOR A TIME. ASIDE
FROM THAT VFR CONDITIONS ARE EXPECTED THROUGH TONIGHT. WINDS WILL
BE GENERALLY LESS THAN 10 KNOTS AND FAVORING A SOUTHEASTERLY
DIRECTION BY AFTERNOON AT KDEN AND KAPA WHEREAS KBJC WILL BEGIN
COMING UNDER THE INFLUENCE OF MOUNTAIN WAVE/LEE TROUGH ACTIVITY
KEEPING THE WINDS OUT OF THE WEST. THEY COULD ALSO SEE SOME GUSTS
INTO THE 20S BY AFTERNOON.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...WIND CHILL ADVISORY UNTIL 8 AM
MST THIS MORNING FOR COZ042- 044>046-048>051.
&&
$$
SHORT TERM...ET
LONG TERM....RJK
AVIATION...ET
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
709 AM EST MON JAN 6 2014
.SYNOPSIS...
A POTENT COLD FRONT WILL CROSS THE REGION THIS MORNING. ARCTIC
HIGH PRESSURE WILL THEN BUILD IN WAKE OF THE FRONT AND LINGER
THROUGH THE MIDDLE OF THE WEEK. A COASTAL TROUGH WILL THEN DEVELOP
OFFSHORE LATE WEEK BEFORE ANOTHER COLD FRONT APPROACHES THE AREA LATE
WEEKEND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AROUND 12Z...THE COLD FRONT INTO OUR WESTERN ZONES WITH 12-14 DEGREE
TEMP FALLS IN THE PAST HOUR AT SYLVANIA AND STATESBORO. ON AN EARLIER
UPDATE...WE INITIALIZED THE WIND ADVISORY WE HAD ISSUED PRIOR TO BE
IN EFFECT IMMEDIATELY SINCE GUSTS HAVE ALREADY TOPPED 30 KT AT
TIMES TRAILING THE FROPA.
THE STRONG COLD FRONT WILL SWEEP THROUGH THE AREA THIS MORNING
WITH ARCTIC HIGH PRESSURE BEGINNING TO USHER IN BEHIND. PRECIP
POTENTIAL WITH THE FRONTAL PASSAGE LOOKS RATHER LOW GIVEN THE FACT
THAT MODEL TIME SECTIONS SHOW THE MOISTURE SCOURING OUT BY SHORTLY
AFTER DAYBREAK. THERE WILL PROBABLY BE A POCKETS OF LIGHT RAIN
SHOWERS ACCOMPANYING THE FRONT...MOVING OFF THE COAST BY MID TO
LATE MORNING. WE HAVE 20-30 PERCENT POPS DROPPING OFF BY NOON.
CLEARING EXPECTED INLAND DURING THE AFTERNOON AS MUCH DRIER AIR
FILTERS IN. THE INTENSE UPPER JET SEGMENT CLOSE TO 200 KT AT 250
MB MOVING INTO GEORGIA AND THE UPSTATE CAROLINAS SHOULD PRODUCE
BAND OF HIGH CLOUDS THIS AFTERNOON AND EVENING...A BIT UNCERTAIN
OF THEIR OPACITY AT THIS TIME.
WINDY CONDITIONS DEVELOP BY MID MORNING IN THE WAKE OF THE FRONT.
LOW-LEVEL WINDS WILL RAPIDLY INCREASE WITH WIND SPEEDS ATOP THE
MIXED LAYER INCREASING TO 35 KT BY LATE AFTERNOON. THE GUSTY WNW
WINDS COMBINED WITH STRONG COLD ADVECTION HAVE PROMPTED THE
ISSUANCE OF A WIND ADVISORY FOR SE GEORGIA AND EXTREME SOUTHERN
SOUTH CAROLINA BORDERING THE SAVANNAH RIVER. RECENT RAP MODEL
OUTPUT INDICATE A NOSE OF ENHANCED 1000 MB GEOSTROPHIC FLOW ARCING
INTO OUR SOUTHERN ZONES LIKE A BLADE TODAY. STRONG DOWNHILL
MOMENTUM...RAPIDLY DRYING AND SINKING AIR POST FRONTAL WERE ENOUGH
OF A CONCERN TO ISSUE THE ADVISORY FOR PERIODS OF STRONG WIND
GUSTS AT OR SLIGHTLY ABOVE 40 MPH. IN THE CHARLESTON TRI-COUNTY
AREA THE GUSTS NOT QUITE AS STRONG AS SAVANNAH GIVEN THE OFFSHORE
PUSH AROUND THE SOUTHERN END OF THE MOUNTAINS SO WE HELD OFF.
TODAY/S SHIFT WILL MONITOR TRENDS FOR ANY POSSIBLE EXTENSION IN
EITHER SPACE OR TIME.
STRONG COLD ADVECTION CONTINUES INTO TONIGHT WITH A DOWN-RIGHT COLD
AIRMASS SETTLING OVER THE AREA. LOW TEMPS WILL BE IN THE MID TEENS
FAR INLAND WITH UPPER TEENS TO LOWER 20S ALL THE WAY TO THE COAST.
ALTHOUGH LOW-LEVEL WINDS DROP OFF CONSIDERABLY AFTER MIDNIGHT...
BREEZY WINDS PERSIST DUE TO THE STRONG COLD ADVECTION. WE ARE IN
LINE WITH NEIGHBORING OFFICES WITH THE ISSUANCE OF A WIND CHILL
ADVISORY FOR LATE TONIGHT INTO MID TUESDAY MORNING. IT IS STILL
POSSIBLE THAT OUR WIND CHILL FORECAST MAY BE JUST A TAD LOW GIVEN
UNCERTAINTIES OF ACTUAL WIND SPEEDS DURING THE HOURS AROUND
DAYBREAK TUESDAY. HOWEVER GIVEN THE ANOMALOUS AIR MASS...IMPACTS WITH
WIND/COLD OF THIS NATURE WERE TAKEN SERIOUSLY FOR THOSE EXPOSED TO
THESE ELEMENTS. WE WILL REISSUE A PNS ON THE COLD WEATHER EARLY
THIS MORNING.
LAKE WINDS...DANGEROUS BOATING CONDITIONS WILL LIKELY DEVELOP IN
THE WAKE OF STRONG COLD FRONT LATER TODAY AND ESPECIALLY AFTER
SUNSET INTO THE EVENING HOURS.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
TUESDAY...A WIND CHILL ADVISORY WILL LIKELY BE ONGOING FOR ALL
AREAS THROUGH LATE MORNING WITH ZERO TO 5 DEGREE WIND CHILL VALUES
EVEN UP ALONG THE COAST AS A WEST/NORTHWEST WIND CONTINUES. WINDS
WILL THEN BEGIN TO RELAX WHILE TEMPS GRADUALLY WARM...PUTTING AN
END TO A WIND CHILL ADVISORY BY 11 AM. DESPITE AN IMPROVEMENT TO
TEMPS AND WINDS...ARCTIC HIGH PRESSURE WILL CONTINUE TO BUILD FROM
THE WEST AND NORTHWEST...BECOMING CENTERED OVER OR JUST NORTH OF
THE AREA BY TUESDAY NIGHT. THE PATTERN WILL FAVOR ONGOING STRONG
COLD AIR ADVECTION OVER SOUTHEAST SOUTH CAROLINA AND SOUTHEAST
GEORGIA THROUGHOUT THE DAY WHILE THE AREA REMAINS ALONG THE
SOUTHERN PERIPHERY OF A LARGE MID LVL TROUGH SHIFTING OFF THE
EASTERN SEABOARD. AS A RESULT...HIGH TEMPS ON TUESDAY WILL BE SOME
OF THE COLDEST WE HAVE SEEN SO FAR THIS YEAR. EXPECT TEMPS TO PEAK
ONLY IN THE LOW/MID 30S INLAND TO MID/UPPER 30S ALONG THE COAST.
WEATHER CONDITIONS WILL REMAIN DRY WITH THE ARCTIC AIRMASS IN
PLACE.
OVERNIGHT LOWS WILL BE VERY COLD ONCE AGAIN...MAINLY DUE TO THE
POSITION OF THE ARCTIC HIGH AND STRONG RADIATIONAL COOLING UNDER
LIGHT/CALM WINDS. EXPECT LOW TEMPS IN THE MID/UPPER TEENS INLAND AND
MID/UPPER 20S ALONG THE COAST. WIND CHILL TEMPERATURES MAY REACH AS
LOW AS 15 TO 20 DEGREES.
WEDNESDAY AND THURSDAY...CONDITIONS WILL REMAIN DRY ON WEDNESDAY AS
THE CENTER OF VERY COLD/DRY HIGH PRESSURE SLOWLY SHIFTS OFF THE MID
ATLANTIC COAST. A COASTAL TROUGH WILL THEN BEGIN TO DEVELOP OFFSHORE
ALONG THE SOUTHERN EDGE OF THE SFC HIGH WEDNESDAY NIGHT AND
THURSDAY. THE PATTERN WILL RESULT IN A GRADUAL MODIFICATION OF TEMPS
AS MID LVL RIDGING OCCURS OVER THE SOUTHEASTERN UNITED STATES WHILE
SFC WINDS SHIFT FROM NORTHWEST TO NORTHEAST. HOWEVER...TEMPS MAY
STRUGGLE TO WARM SIGNIFICANTLY OVER INLAND AREAS WHERE SFC HIGH
PRESSURE EXTENDS SOUTHWEST FROM THE CENTER OF THE ARCTIC HIGH OFF THE
MID ATLANTIC COAST. AS A RESULT...WARMEST TEMPS SHOULD OCCUR NEAR
THE COAST IN SOUTHEAST SOUTH CAROLINA AND SOUTHEAST GEORGIA WHERE
ONSHORE FLOW DEVELOPS. EXPECT OVERALL HIGHS IN THE MID/UPPER 40S ON
WEDNESDAY...WITH OVERNIGHT LOWS IN THE LOW 30S INLAND TO UPPER
30S/LOWER 40S ALONG THE COAST. TEMPS SHOULD THEN WARM INTO THE
MID/UPPER 50S INLAND TO LOWER 60S ALONG THE COAST ON THURSDAY.
CHANCES OF PRECIP SHOULD ALSO INCREASE WITH ISENTROPIC ASCENT AND
THE STRENGTHENING OF THE COASTAL TROUGH JUST OFFSHORE ON THURSDAY.
HOWEVER...PRECIP ACTIVITY COULD HAVE A TOUGH TIME MAKING IT WELL
INLAND WHERE HIGH PRESSURE LINGERS. HAVE THEREFORE MAINTAINED SLIGHT
CHANCE POPS IN THE FORECAST AT THIS TIME.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
A COASTAL TROUGH WILL CONTINUE TO STRENGTHEN ALONG THE SOUTHERN
PERIPHERY OF HIGH PRESSURE OFF THE MID ATLANTIC COAST THROUGH LATE
WEEK. THIS FEATURE ALONG WITH ISENTROPIC LIFT SHOULD SUPPORT A FEW
SHOWERS OVER THE AREA ON FRIDAY...BEFORE COVERAGE INCREASES ON
SATURDAY AS THE COASTAL TROUGH LIFTS NORTH WITH A WARMER AIR MASS
WELL AHEAD OF A COLD FRONT/SFC LOW APPROACHING FROM THE WEST. FORECAST
CONFIDENCE REMAINS VERY LOW WITH REGARDS TO THE TIMING AND STRENGTH
OF THE COLD FRONT/SFC LOW APPROACHING THE SOUTHEASTERN UNITED
STATES...BUT THE GENERAL CONSENSUS IS THAT TEMPS WILL WARM
CONSIDERABLY AND CHANCES OF PRECIP WILL INCREASE UNTIL THE FEATURE
SHIFTS OFFSHORE EARLY NEXT WEEK. HAVE THEREFORE MAINTAINED A 30-40
POP SCHEME SUNDAY...BEFORE GRADUALLY LOWERING POPS ON MONDAY.
OVERALL...HIGH TEMPS SHOULD REACH THE LOWER 60S ON FRIDAY...THEN
MID/UPPER 60S ON SATURDAY AND SUNDAY...BEFORE SLIGHTLY COOLING INTO
THE LOW/MID 60S ON MONDAY. OVERNIGHT LOWS SHOULD ALSO SHOW A WARMING
TREND INTO EARLY NEXT WEEK...WITH TEMPS STARTING IN THE UPPER 30S TO
MIDDLE 40S THURSDAY NIGHT...THEN UPPER 40S TO MIDDLE 50S THIS
WEEKEND AND EARLY NEXT WEEK.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
IFR CIGS AT THE TERMINALS OVERNIGHT HAD LIFTED TO MVFR RECENTLY
AND THE WINDOW FOR ADDITIONAL IFR CONDITIONS IS QUICKLY CLOSING
AS THE LEADING EDGE OF THE MUCH COOLER AIR IS APPROACHING. LIGHT
SHOWERS AROUND THE COASTAL CORRIDOR FROM 12Z-16Z...THEN VFR WITH
ALL CONCERNS REVOLVING AROUND WIND SPEEDS AND GUSTS INTO TONIGHT.
FREQUENT GUSTS 25-30 KT ARE LIKELY THROUGH THIS EVENING WITH SOME
GUSTS UP TO 35 KT POSSIBLE DURING THE STRONGEST PRES RISES LATER
THIS MORNING INTO THIS AFTERNOON. THE BEST CHANCES FOR GUSTS THIS
HIGH COULD BE AT KSAV WHERE A WIND ADVISORY IS IN EFFECT. WINDS
SHOULD DIMINISH TOWARD 08Z-12Z WITH THE COLDER AIR ARRIVING.
EXTENDED AVIATION OUTLOOK...GUSTY WINDS ARE POSSIBLE AT BOTH
TERMINALS EARLY TUESDAY. OTHERWISE...VFR CONDITIONS SHOULD PREVAIL
TUESDAY INTO THURSDAY. ANOTHER ROUND OF MVFR CIGS/VSBYS IS POSSIBLE
FRIDAY AND SATURDAY AS A COASTAL TROUGH LIFTS NORTH OVER THE AREA.
&&
.MARINE...
A SIGNIFICANT MARINE EVENT WILL UNFOLD TODAY AND TONIGHT ACROSS
ALL OF THE WATERS BEHIND A STRONG COLD FRONT. 35-40 KT BOUNDARY
LAYER WINDS COMBINED WITH VERY STRONG COLD ADVECTION MOVING OVER
THE WARMER ATLANTIC WATERS WILL RESULT IN GALE CONDITIONS
BEGINNING THIS MORNING SOUTH OF CHARLESTON AND CONTINUING THROUGH
MUCH OF TONIGHT. THE STRONGEST SURGE IN SURFACE WINDS WILL LIKELY
BE THIS EVENING INTO THE FIRST PART OF THE OVERNIGHT AS -6C TO -12C
TEMPS AT H925 PLOW OVER THE WATERS. THERE IS A LOT OF MESOSCALE
INFLUENCES AND NUANCES INVOLVED WITH A COASTAL WATERS FORECAST LIKE
THIS AND WE BEGIN TO TRY TO SHOW SOME OF THE DETAILS IN THE GRIDS
THIS MORNING. THE OVERALL BOTTOM LINE TO ANYONE WITH MARINE INTEREST
IS PREPARE FOR EXTREMELY NASTY CONDITIONS WITH THE ADDED CONCERN
OF WIND CHILLS IN THE 10-20 DEGREE RANGE.
TUESDAY THROUGH FRIDAY...SMALL CRAFT ADVISORIES WILL LIKELY BE
ONGOING FOR ALL WATERS EARLY TUESDAY BEFORE WINDS/SEAS STEADILY
IMPROVE AS STRONGER LOW LVL WINDS SHIFT NORTHEAST AND AWAY FROM THE
AREA BY TUESDAY AFTERNOON. AS A RESULT...SMALL CRAFT ADVISORIES
WILL LIKELY NOT BE NEEDED BY TUESDAY AFTERNOON FOR NEARSHORE WATERS
AND BY TUESDAY EVENING FOR OFFSHORE GEORGIA WATERS. WINDS/SEAS
COULD APPROACH SMALL CRAFT ADVISORY LEVELS OVER OUTER GEORGIA WATERS
WEDNESDAY NIGHT INTO THURSDAY AS A COASTAL TROUGH DEVELOPS
OFFSHORE...WITH WINDS GUSTING UP TO 20-25 KT AND SEAS BUILDING UP TO
6 FT. CONDITIONS SHOULD THEN REMAIN BELOW SMALL CRAFT ADVISORY
LEVELS INTO EARLY WEEKEND AS THE COASTAL TROUGH BEGINS TO LIFT NORTH
WITH A FEW SHOWERS OVER THE WATERS.
&&
.TIDES/COASTAL FLOODING...
ANOTHER ROUND OF BLOW-OUT TIDES ARE LIKELY ON LOW TIDES TONIGHT WITH
THE PASSAGE OF AN ARCTIC COLD FRONT. STRONG OFFSHORE FLOW AROUND
LOW TIDE COULD RESULT IN VERY LOW WATER LEVELS. THE LOW TIDE AROUND
DAYBREAK ON TUESDAY LOOKS THE MOST SIGNIFICANT.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR GAZ087-088-
099>101-114>119-137>141.
WIND CHILL ADVISORY FROM 1 AM TO 10 AM EST TUESDAY FOR GAZ087-
088-099>101-114>119-137>141.
SC...WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR SCZ040-042-047-
048-051.
WIND CHILL ADVISORY FROM 1 AM TO 10 AM EST TUESDAY FOR SCZ040-
042>045-047>052.
LAKE WIND ADVISORY UNTIL NOON EST TUESDAY FOR SCZ045.
MARINE...GALE WARNING UNTIL 4 AM EST TUESDAY FOR AMZ330-350-352-354.
GALE WARNING UNTIL 6 AM EST TUESDAY FOR AMZ374.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...DPB
LONG TERM...DPB
AVIATION...
MARINE...DPB
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
642 AM EST MON JAN 6 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 448 AM EST MON JAN 6 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP UPR TROF IN
CENTRAL NAMERICA AS ARCTIC/POLAR BRANCHES ARE IN THE PROCESS OF
PHASING...WITH THE AXIS OF LOWEST HGTS STRETCHING FM HUDSON BAY INTO
THE UPR MS RIVER VALLEY. WITHIN THE CORE OF THE COLDEST AIR...00Z
RAOBS SHOW H5/H85/H925 TEMPS AS LO AS -45C/-34C/-34C. THE PHASING OF
THE UPR BRANCHES IS SUPPORTING A DEEPENING SFC LO MOVING NNEWD INTO
SE ONTARIO. ALTHOUGH THE SYNOPTIC SCALE FORCING/PCPN ASSOCIATED WITH
THIS SFC LO ARE PASSING TO THE E OF UPR MI...SHARPENING CYC NNW FLOW
ON THE NW FLANK OF THE LO AND AREA OF DPVA/DEEP LYR QVECTOR CNVGC/
DEEPENING MID LVL MSTR AHEAD OF THE ARCTIC BRANCH SHRTWV ARE
IMPACTING MAINLY THE E HALF OF UPR MI...CAUSING AN INCRS IN LES
INTENSITY/COVERAGE IN THE FAVORED SN BELTS. AN AREA OF DEEPER MSTR
ALSO STRECHES FM NW ONTARIO S INTO MN UNDER THE AXIS OF LOWER HGTS.
TEMPS REMAIN WELL BLO NORMAL. 00Z H85 TEMPS OVER UPR MI RANGED FM
ABOUT -19C OVER THE SE TO -25C OVER THE W... SUPPORTING SFC TEMPS AS
LO AS -20F OVER THE FAR W NEAR THE WI BORDER EARLY THIS MRNG. THE
MORE NNW FLOW OFF LK SUP HAS MODERATED THE AIRMASS DOWNWIND OF THE
LK OVER THE ERN CWA...WHERE TEMPS NEAR LK SUP REMAIN CLOSE TO 10F.
THE INCRSG WINDS HAVE CAUSED WIND CHILLS TO FALL AS LO AS -35 TO
-40F OVER THE WRN CWA.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON HEADLINES RELATED TO
TEMPS/WIND CHILLS AS WELL AS LES/BLSN.
TDAY...SFC LO OVER SE ONTARIO EARLY THIS MRNG IS PROGGED TO LIFT
NEWD INTO QUEBEC AND INTENSIFY AS AXIS OF LOWEST HGTS ALF DRIFTS E
ACROSS THE UPR LKS. ALTHOUGH THE AREA OF SHARPER QVECTOR CNVGC TO
THE E OF THE UPR TROF IS PROGGED TO DRIFT TO THE E AND AWAY FM
NEWBERRY BY LATE AFTN...AREA OF DEEPER MSTR/CORE OF COLDER AIR NOTED
TO THE W IS PROGGED TO DRIFT E THRU THE UPR LKS AS WELL. THE COLDEST
H85 TEMPS ARE FCST TO PASS TO THE S THRU WI...BUT THE STEADILY
BACKING LLVL FLOW TOWARD THE W BY 00Z TUE ASSOCIATED WITH THE
DEPARTING SFC LO TO THE NE WL ALLOW FOR LESS LK SUP MODERATION OF
THE BITTERLY COLD AIRMASS. THE FOCUS OF THE HIER LES POPS WL SHIFT
AS WELL WITH THESE BACKING WINDS. ALTHOUGH ABSENCE OF DGZ WITH
BITTERLY COLD AIR WL LIMIT SN ACCUMS OVER THE W...ARRIVAL OF DEEPER
MSTR WL KEEP CONTINUOUS -SHSN GOING. SMALL SN FLAKES WL EFFICIENTLY
REDUCE VSBY AS BLSN INCREASES WITH SLOWLY INCRSG WINDS. EXPECT
SOMEWHAT HEAVIER SHSN OVER THE E WHERE LES ADVY IS IN PLACE GIVEN
SOME LINGERING DYNAMIC FORCING/WARMER AIR THAT DOES NOT HAMPER SN
GROWTH AS MUCH... BUT THE SHIFTING WINDS WL TEND TO CAUSE THE LES
BANDS TO DRIFT AS WELL. AS FOR TEMPS/WIND CHILLS...EXPECT LTL IF ANY
DIURNAL RECOVERY WITH BACKING LLVL FLOW LIMITING LK MODERATION. OVER
THE E...THIS BACKING FLOW MAY CAUSE TEMPS TO FALL. SINCE WIND SPEEDS
WL BE ON THE INCRS AS WELL...GOING WIND CHILL HEADLINES SEEM TO BE
ON TRACK.
TNGT...MODELS HINT ANOTHER SHRTWV DIVING SEWD ARND SLOWLY DEPARTING
UPR TROF AXIS WL MOVE INTO THE UPR LKS...BRINGING ANOTHER ROUND OF
DPVA/DEEP LYR QVECTOR CNVGC THAT MAINTAINS DEEPER MSTR. AS THE SFC
FLOW BACKS WITH LAND BREEZE ENHANCEMENT...LLVL CNVGC WL INCRS OVER
NRN ONTONAGON/CENTRAL HOUGHTON COUNTIES AND NEAR LK SUP E OF
MUNISING. THIS INCRSG LAND BREEZE COMPONENT WL TEND TO ADVECT LESS
MODIFIED AIR INTO THE CWA AND OFFSET SLOWLY MODERATING H85 TEMPS
WITH PASSAGE OF COLDEST CORE TO THE E. SINCE THE LLVL WINDS ARE FCST
TO INCRS AS WELL...WARNING THRESHOLD WIND CHILLS ARE LIKELY OVER
ALMOST ALL OF THE CWA.
AS FOR HEADLINES...GOING WIND CHILL WARNINGS APPEAR TO BE ON TRACK
EVEN THOUGH MORE LK MODIFIED AIR HAS MAINTAINED HIER TEMPS OVER
ABOUT THE E HALF OF THE CWA. BACKING/INCRSG WINDS LATER TDAY/TNGT
SHOULD ADVECT SUFFICIENTLY COLD AIR OVER THE ENTIRE CWA TO JUSTIFY
MAINTAINING ALL WIND CHILL WRNGS. ALTHOUGH SN AMOUNTS OVER THE W ARE
NOT LIKELY TO REACH ADVY THRESHOLDS...OPTED TO ISSUE AN LES ADVY FOR
ONTONAGON COUNTY THRU THE KEWEENAW THRU TUE TO ACCOUNT FOR THE
FREQUENT WHITEOUTS THAT WL LIKELY OCCUR WITH THE FALLING AND BLOWING
OF THE SMALL SN FLAKES. EXTENDED THE LES ADVY FOR ALGER/LUCE
COUNTIES THRU TUE AS WELL GIVEN THE POTENTIAL FOR HEAVIER SHSN
ESPCIALLY NEAR LK SUP E OF PICTURED ROCKS IN THE SHARPER LLVL CNVGC
THAT WL DVLP WITH SHARPENING LAND BREEZE CNVGC/WARMER H85 TEMPS THAT
WL NOT IMPACT SN GROWTH AS MUCH AS OVER THE W.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 448 AM EST MON JAN 6 2014
THE 500MB LOW RESPONSIBLE FOR THE ACTIVE WEATHER ACROSS THE GREAT
LAKES THIS WEEK WILL BE OVER QUEBEC TUESDAY MORNING. THIS LOW WILL
LINGER A TROUGH OVER THE GREAT LAKES THROUGH THE DAY TUESDAY AND
WEDNESDAY. AT THE SURFACE...HIGH PRESSURE WILL SINK TOWARDS THE GULF
OF MEXICO. THE SURFACE LOW OVER THE LOWER LAKES MONDAY NIGHT WILL
MAKE ITS WAY INTO QUEBEC BY TUESDAY...KEEPING A WEAK TROUGH OVER
EASTERN LAKE SUPERIOR THROUGH WEDNESDAY. OVERALL...UPPER MI WILL
REMAIN IN WEST-NORTHWEST FLOW THROUGH THE FIRST PORTION OF THE LONG
TERM...CAUGHT BETWEEN THE HIGH IN THE SOUTHEAST AND THE LOW IN
QUEBEC. THOUGH WINDS WILL BE GUSTY THROUGH MOST OF TUESDAY...THEY
WILL GRADUALLY LESSEN AS THE HIGH MAKES ITS WAY INTO THE CWA TUESDAY
NIGHT INTO WEDNESDAY. WITH THE COLD ARCTIC AIR IN PLACE...LES WILL
CONTINUE IN WNW-WIND FAVORED SNOWBELTS. WITH DWINDLING
MOISTURE/EXTREME COLD...SNOW RATIOS WILL BE UNSUPPORTIVE OF
SIGNIFICANT ACCUMULATIONS ACROSS THE AREA FOR THIS TIME PERIOD. FOR
NOW HAVE 2 TO 4 INCHES OF ACCUMULATION FROM TUESDAY MORNING INTO
WEDNESDAY MORNING FOR EASTERN ALGER/LUCE COUNTY...AND 1 TO 2 INCHES
ACROSS ONTONAGON...HOUGHTON...AND KEWEENAW COUNTY.
THE MAIN CONCERN WILL BE LOWERED VISIBILITY DUE TO THE SMALL FLAKE
SIZE AND BLOWING SNOW/FROM GUSTY WNW WINDS/ NEAR THE LAKESHORE ALL
DAY TUESDAY...AND WIND CHILLS THROUGH LATE TUESDAY MORNING. FOR
HEADLINES...HAVE LES ADVISORY THROUGH TUESDAY IN WNW WIND FAVORED
SNOWBELTS...MAINLY ONTONAGON....NORTHERN
HOUGHTON...KEWEENAW...ALGER...AND LUCE COUNTIES TO ACCOUNT FOR THE
SNOW/BLOWING SNOW/WIND CHILL. ELSEWHERE...SOLELY THE WIND CHILL
WARNING REMAINS IN EFFECT. WIND CHILLS TUESDAY MORNING WILL RANGE
FROM -50F TO -25F ACROSS THE FORECAST AREA...WITH THE COLDEST
READINGS ACROSS THE INTERIOR WEST.
THE HIGH WILL GRADUALLY CROSS THE GREAT LAKES LATE WEDNESDAY INTO
THURSDAY...AND THEN REACH THE NEW ENGLAND STATES BY THURSDAY NIGHT.
AS THE HIGH MOVES OUT...WINDS BACK TO THE SOUTHWEST. THIS BRINGS
EXTREMELY DRY AIR INTO MUCH OF THE CWA BY EARLY WEDNESDAY
EVENING...STARTING A DISSIPATING TREND TO THE LES THROUGH THURSDAY
MORNING. ADDITIONALLY...WITH WINDS BACKING SOUTHWEST...MOST OF THE
REMAINING LES WILL MOVE OFFSHORE INTO LAKE SUPERIOR. THE BEST CHANCE
FOR SNOW SHOWERS ON THURSDAY IS OVER THE KEWEENAW.
MODELS BEGIN TO DISAGREE LATE THURSDAY INTO FRIDAY ON HOW TO HANDLE
AN UPPER LEVEL TROUGH MOVING INTO THE NORTHERN PLAINS...BOTH WITH
THE TIME AND STRENGTH OF THE OVERALL FEATURE. THE ECMWF BRINGS A
MORE SHALLOW TROUGH ACROSS THE GREAT LAKES FRIDAY NIGHT/SAT
MORNING...WHEREAS THE GFS BRINGS A DEEPER TROUGH THROUGH ON SATURDAY
EVENING. BY THIS TIME...THE ECMWF HAS ZONAL FLOW ALOFT FOR UPPER MI.
THE GEM SEEMS TO BE THE MIDDLE OF THE ROAD...BRINGING THE TROUGH
THROUGH THE GREAT LAKES SATURDAY AFTERNOON...WITH A STRENGTH SIMILAR
TO THAT OF THE ECMWF. BY SUNDAY AND MONDAY...THESE DIFFERENCES ARE
EXACERBATED...ESPECIALLY AT THE SURFACE. THE ECMWF KEEPS A WEAK SURFACE
TROUGH OVER THE GREAT LAKES THROUGH SUNDAY AFTERNOON...AND THEN
BRINGS A SURFACE HIGH ACROSS THE NORTHERN PLAINS INTO THE GREAT LAKES
FOR MONDAY. THE GFS BRINGS A CLOSED LOW PRESSURE SYSTEM ACROSS
MANITOBA AND INTO JAMES BAY...WHICH KEEPS A TROUGH OVER UPPER MI.
WILL KEEP THE CONSENSUS POPS FOR NOW GIVEN SUCH DRAMATIC DIFFERENCES.
ON A POSITIVE NOTE...MODELS TRENDING UPWARD WITH TEMPERATURES THROUGH
THE PERIOD...WITH HIGHS IN THE UPPER 20S AND LOW 30S BY NEXT WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 641 AM EST MON JAN 6 2014
EXTREME COLD AIRMASS MOVING ACROSS THE UPPER GREAT LAKES WILL ALLOW
FOR LAKE EFFECT SNOW SHOWERS TO CONTINUE THROUGH THE PERIOD AT CMX
AND IWD. THE COMBINATION OF FALLING AND BLOWING OF THE SMALL SN
FLAKES AT THESE LOCATIONS WL RESULT IN IFR WX. THE WORST CONDITIONS
WL BE AT THE MORE EXPOSED CMX LOCATION TNGT...WHERE VLIFR CONDITIONS
WL BE THE RULE WITH INCRSG WNW WINDS. EXPECT VFR CONDITIONS TO
PREDOMINATE AT SAW WITH A DOWNSLOPE WNW WIND COMPONENT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 448 AM EST MON JAN 6 2014
WITH SHARPENING PRES GRADIENT AND FLOW OF ARCTIC AIR OVER THE
RELATIVELY WARM LK WATERS...EXPECT WNW WINDS 30 KTS TO GALES TO 35
KTS THRU TONIGHT INTO TUESDAY EVENING. MAINTAINED GOING GALE
WARNINGS. THE COMBINATION OF THE BITTER COLD/SIGNIFICANT WAVE ACTION
WILL RESULT IN WIDESPREAD HEAVY FREEZING SPRAY AS WELL...SO LEFT THE
HEAVY FREEZING SPRAY WARNINGS IN EFFECT THROUGH WEDNESDAY MORNING.
OTHERWISE...HIGH PRESSURE WILL MAKE ITS WAY SOUTH OF LAKE SUPERIOR
BY MID WEEK...BUT A PERSISTANT LOW PRESSURE TROUGH NORTH OF THE LAKE
WILL KEEP WNW WINDS GUSTING TO 15 TO 25 KTS THROUGH THURSDAY.
TOWARDS THE LATTER PORTION OF THE WEEK...ANOTHER LOW PRESSURE TROUGH
WILL APPROACH THE GREAT LAKES FROM THE NORTHERN PLAINS...BACKING
WINDS TO THE SOUTHWEST AT 15 TO 25 KNOTS FOR THURSDAY AND FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL WARNING UNTIL 11 AM EST /10 AM CST/ TUESDAY FOR
MIZ001>005-009>013-084.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ014-
085.
WIND CHILL WARNING FROM 7 PM THIS EVENING TO 11 AM EST TUESDAY
FOR MIZ006-007-014-085.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST TUESDAY FOR MIZ001>003-
006-007.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ WEDNESDAY
FOR LSZ162-243>245-248>251-263>267.
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LSZ265-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...MCD
AVIATION...KC
MARINE...KC/MCD
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
529 AM CST MON JAN 6 2014
.AVIATION...
12Z TAFS FOR KOFK...KOMA AND KLNK.
HIGH PRESSURE RIDGE AXIS WILL MOVE INTO EXTREME ERN NEBRASKA
THROUGH LATE AFTERNOON BEFORE SHIFTING OFF TO THE EAST TONIGHT.
OCCASIONALLY GUSTY NORTHWEST SURFACE WINDS WILL PERSIST TODAY EAST
OF THE RIDGE AXIS BEFORE DECREASING TOWARD SUNSET THEN TURNING SW
THIS EVENING. CLOUD PATCHES...CURRENTLY DIFFICULT TO DISCERN ON
SATELLITE DUE TO SMALL TEMPERATURE CONTRASTS WITH ARCTIC
AIR...WILL SLIDE ACROSS THE TAF SITES THROUGH MIDDAY. THIS COULD
POSSIBLY BRING A PERIOD OF MVFR CIGS TO TAF SITES...ESPECIALLY AT
OMAHA AND NORFOLK. MID CLOUDS ABOVE FL070 SHOULD DEVELOP/SPREAD
ACROSS THE AREA OVERNIGHT AS THE HIGH SLIDES OFF TO THE EAST.
CHERMOK
&&
.PREV DISCUSSION... /ISSUED 258 AM CST MON JAN 6 2014/
DISCUSSION...
CENTER OF ARCTIC HIGH PRESSURE HAD SHIFTED SOUTH OF THE AREA AT
08Z OVER OKLAHOMA WITH SURFACE GRADIENT WEAKENING OVER NEBRASKA.
AS A RESULT SURFACE WINDS BECOMING MORE VARIABLE EARLY THIS
MORNING WITH REGARD TO SPEED. SEVERAL SITES REPORTING LESS THAN
10 KTS AT 08Z. WIND CHILL VALUES HOWEVER GENERALLY RANGE FROM -25
TO -35 ACROSS THE FORECAST AREA. RAP INDICATES SURFACE GRADIENT
MAY INCREASE AGAIN DURING THE MORNING WITH WINDS PICKING UP TO
BETWEEN 10 AND 20 KTS.
ADJUSTMENTS TO CURRENT HEADLINES MAY BE NEEDED BEFORE EXPIRATION
BUT WILL PASS THIS ON TO THE DAY SHIFT TO BETTER DELINEATE TRENDS
AND AREAL IMPACT.
TEMPERATURES ARE STILL EXPECTED TO REMAIN BELOW ZERO TODAY FROM
NORTHEAST NEBRASKA INTO SOUTHWEST IOWA WITH ONLY LOW SINGLE
DIGITS TO THE WEST OF THAT AREA. SUBZERO TEMPERATURES LIKELY TO
REMAIN ACROSS MOST OF THE AREA YET TONIGHT BUT RELATIVELY WARMER
TEMPERATURES RETURN ON TUESDAY IN ADVANCE OF A WEAK CLIPPER COMING
OUT OF THE NORTHERN ROCKIES. ANOTHER PUSH OF COLD AIR MOVES INTO
THE REGION BEHIND THIS SYSTEM TUESDAY NIGHT INTO WEDNESDAY BUT NOT
AS EXTREME AS CURRENT AIRMASS OVER THE REGION.
MODELS INDICATE LESS AMPLIFIED FLOW BY WEDNESDAY WITH SPLIT FLOW
DEVELOPING IN THE EXTENDED PORTION OF THE FORECAST. THIS IS
EXPECTED TO RESULT IN TEMPERATURES CLOSER TO NORMAL OR SLIGHTLY
ABOVE FOR EARLY JANUARY. ALTHOUGH NO MAJOR WINTER STORM SYSTEM IS
INDICATED...SHORT WAVES MOVING THROUGH THE FLOW DURING THIS TIME
MAY TRIGGER PERIODS OF LIGHT SNOW FOR PARTS OF THE AREA BUT TIMING
AND STRENGTH UNCERTAIN FOR LIMITED CONFIDENCE IN ANY MENTION
BEYOND SLIGHT POPS.
FOBERT
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WIND CHILL WARNING UNTIL MIDNIGHT CST TONIGHT FOR NEZ011-012-
015>018-030>034-042>045-050>053.
WIND CHILL WARNING UNTIL 6 PM CST THIS EVENING FOR NEZ065>068-
078-088>093.
IA...WIND CHILL WARNING UNTIL MIDNIGHT CST TONIGHT FOR IAZ043-055-056-
069.
WIND CHILL WARNING UNTIL 6 PM CST THIS EVENING FOR IAZ079-080-
090-091.
&&
$$
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
307 PM PST Mon Jan 6 2014
.Synopsis...
High pressure along the west coast will continue dry and warm
weather today. A slight chance of showers will be possible the
remainder of the week, especially over the northern mountains as
a couple of weak low pressure systems move through the region.
&&
.Discussion...
Ridge axis shifting further inland this afternoon and is showing
signs of breaking down ahead of a series of approaching waves.
High clouds associated with the first of these waves moved in
overnight and are continuing to stream in this afternoon.
Temperature modification from these clouds resulted in a warm
start to the day, and now running five to ten degrees cooler than
yesterday. Expect general cloudiness to persist for much of this
week as the dirty ridge pattern persists.
Ridge is forecast to flatten over the next 12 hours and give way
to the first wave of the week. This wave will rotate over and
around the remnants of the ridge and most likely stay out of our
forecast region, however the HRRR model does hint at a few stray
showers in the Northern Sacramento valley tonight. A second wave
arrives midweek and could drop further into California than the
first wave. Uncertainty is higher than average given the weak
organization of these wave. That said, timing on the second wave
is late Wed into early Thursday. The Northern and Central
Sacramento valley as well as the sierra could see some
precipitation from the second wave. Neither system appears to be
especially wet, so any accumulations will be light.
&&
.Extended Discussion (Friday through Monday)
The extended forecast starts with a warm and dry Friday as daytime
highs measure up to around 10 degrees above normal. Models are
indicating that weak, unsettled weather could be impacting NorCal
Saturday and Sunday with slightly cooler temperatures. However, discrepancies
exist between the models. The ECMWF continues to be the more
bullish showing a deeper trough and wetter conditions (though
precipitation amounts are still not impressive) that last most of
the weekend. The GFS and GEM show a quick moving weak storm that
brushes NorCal Saturday morning into afternoon then becoming dry
again for Sunday. Have kept slight chance to chance of
precipitation for Saturday across most of our CWA and then only a
slight chance in the northern half of our CWA on Sunday. All
models show another ridge building back over the West Coast by
early Monday. JBB
&&
.Aviation...
Predominantly VFR across interior NorCal next 24 hours, except
areas of MVFR with haze and patchy BR overnight in the Northern
San Joaquin Valley including KSCK. Variable high clouds into this
evening as a weak trough approaches the west coast. Light winds
continue. -DVC
&&
.STO Watches/Warnings/Advisories...
None.
&&
$$
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
916 AM PST Mon Jan 6 2014
.Synopsis...
High pressure along the west coast will continue dry and warm
weather today. A slight chance of showers will be possible the
remainder of the week, especially over the northern mountains as
a couple of weak low pressure systems move through the region.
&&
.Discussion...
Ridge axis shifting inland this morning and is beginning to show
signs of breaking down ahead of a series of approaching waves. High
clouds associated with the first of these waves moved in overnight and
have contributed to slightly warmer temperatures across most locations
this morning. Likewise, daytime highs will be moderated by the
clouds. Redding is running 22 degrees cooler this morning than
yesterday morning, but this is more of a result of weaker winds
than any other factors.
Ridge is forecast to flatten over the next 24 hours and give way
to the first wave of the week. This wave will rotate over and
around the remnants of the ridge and most likely stay out of our
forecast region, however the HRRR model does hint at a few stray
showers in the Northern Sacramento valley tonight. A second wave
arrives midweek and could drop further into California than the
first wave. Uncertainty is higher than average given the weak
organization of these wave. That said, timing on the second wave
is late Wed into early Thursday. The Northern and Central
Sacramento valley as well as the sierra could see some
precipitation from the second wave. Neither system appears to be
especially wet, so any accumulations will be light.
&&
.Extended Discussion (Friday through Monday)
Dry and warmer on Friday as the persistent ridge briefly re-
strengthens with the axis moving inside of 130W. This will put
daytime highs up to 10 degrees above normal. The ridge will
weaken Saturday into Sunday as a trough scrapes off the top layer
of the ridge, and cool temperatures a bit. The models have good
timing with the feature, but the models are not in sync as to the
strength of the next wave. The GFS shows WNW upper flow with
straight-line flow while the ECMWF has decent cyclonic flow.
Finally, the GEM splits the two other models with slight cyclonic
flow. We have trended slightly more toward the ECMWF and kept
some chances of light precipitation for Sat and into Sun. Either
way, this feature is progressive, and an amplified ridge
dominates again Monday with warmer temperatures. JClapp
&&
.Aviation...
Increasing high clouds as a weak trough approaches the west coast.
Light winds today except for some gusty NE winds down the Sierra
today before weakening tonight. Minor MVFR in BR over Nrn San
Joaquin Valley and Srn Sac Valley this morn. JClapp
&&
.STO Watches/Warnings/Advisories...
None.
&&
$$
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
344 PM MST MON JAN 6 2014
.SHORT TERM...UPPER JET HAS MOVED INTO THE CENTRAL PLAINS WITH
WEAKENING NORTHWEST FLOW ALOFT. WINDS HAVE DECREASED CONSIDERABLY
ACROSS THE MOUNTAINS...FOOTHILLS AND PARK COUNTY IN RESPONSE TO
WEAKENING GRADIENT...THOUGH STILL A BIT GUSTY. WESTERLY WINDS HAVE
SPREAD ONTO THE ADJACENT PLAINS OF NORTHERN JEFFERSON COUNTY...
ROUGHLY FROM GOLDEN TO THE BOULDER COUNTY LINE. THERE MAY STILL BE
SOME BLOWING SNOW IN OPEN AREAS. FLOW ALOFT BECOMES A BIT MORE
WESTERLY THIS EVENING AS WEAK UPPER TROUGH MOVES INTO THE NORTHERN
GREAT BASIN. MODELS SHOW A BIT OF A MOUNTAIN WAVE WITH CROSS
MOUNTAIN FLOW AROUND 30 KTS. WINDS TO REMAIN A BIT GUSTY ACROSS
THE MOUNTAINS AND FOOTHILLS WITH SOME GUSTS TO 45 MPH. LATEST HRRR
AND RAP ALSO SHOW WESTERLY WINDS PERSISTING ALONG THE BASE OF THE
FOOTHILLS THROUGH 06Z BEFORE DECREASING OVERNIGHT WITH SOME GUSTS
TO 30 MPH POSSIBLE. SOME POTENTIAL STILL EXISTS FOR BLOWING SNOW
IN OPEN AREAS...BUT LOOKS RATHER LOCALIZED SO WON`T INCLUDE IN
GRIDS FOR NOW. APPEARS BEST HANDLED WITH NOWCASTS. SOME INCREASE
IN MID LEVEL MOISTURE THROUGH THE EVENING AND INTO THE OVERNIGHT
HOURS. CHANCE FOR A WAVE CLOUD DEVELOPING IN AND NEAR THE
FOOTHILLS...AS SHOWN BY CIRA SYNTHETIC SATELLITE IMAGEY BECOMING
FAIRLY EXTENSIVE BETWEEN 09Z AND 15Z. OVERNIGHT LOWS TO MODERATE A
BIT...ESPECIALLY NEAR THE FOOTHILLS OF BOULDER AND JEFFERSON
COUNTY WHERE DOWNSLOPE WINDS WILL AID IN WARMING. LOW LYING AREAS
IN WELD COUNTY WILL STRUGGLE TO STAY ABOVE ZERO. ON TUESDAY...WEST
NORTHWEST FLOW ALOFT WILL PREVAIL. MODELS SHOW THE WEAK TROUGH
MOVING ACROSS WYOMING DURING THE AFTERNOON WITH SOME INCREASE IN
MID LEVEL QG ASCENT ACROSS THE MOUNTAINS LATE IN THE DAY. CROSS
SECTIONS INDICATE AN INCREASE IN IN MOISTURE ABOVE MOUNTAIN TOP.
SOME OROGRAPHICS IN PLACE ACROSS ZONE 31 TO KEEP A SLIGHT CHANCE
OF SNOW GOING. DID DELAY THE ONSET UNTIL 21Z WHEN OROGRAPHICS
BEGINS TO IMPROVE. OTHERWISE...A GRADUAL INCREASE IN CLOUDS. FLOW
ALOFT DECREASES SLIGHTLY THOUGH STILL A BIT OF A MOUNTAIN WAVE.
MAY STILL BE GUSTY OVER THE MOUNTAINS AND ALONG FOOTHILLS.
TEMPERATURES ACROSS PLAINS TO WARM INTO THE MIDDLE 40S MOST
AREAS...WITH UPPER 30S IN LOW LYING AREAS ACROSS WELD COUNTY.
.LONG TERM...SWIFT WEST-NORTHWEST FLOW WILL SEND A SERIES OF WEAK TO
MODERATE PERTABATIONS ACROSS COLORADO DURING THE UPCOMING WEEK.
MODELS GENERALLY AGREE IN PASSING THE NEXT WAVE ACROSS COLORADO
TUESDAY NIGHT/WEDNESDAY MORNING. MOUNTAINS SHOULD SCOOP UP MOST
OF THE MOISTURE CARRIED ALONG BY THIS SYSTEM. SCATTERED TO LIKELY
POPS ARE IN ORDER FOR THE NORTHERN AND CENTRAL MTNS DURING THIS
PERIOD. HOWEVER THE RATHER SHALLOW DEPTH OF THE MOISTURE SHOULD
KEEP ACCUMULATIONS ON THE LOW SIDE. QG VERT VELOCITY FIELDS
INDICATE ONLY WEAK SFC-500 ASCENT WITH ITS PASSAGE TUE NIGHT. ITS
POSSIBLE THE NORTHEAST CORNER OF THE CWFA COULD SEE A FEW
FLURRIES. OTHERWISE IT SHOULD REMAIN DRY EAST OF THE MTNS.
MEANWHILE TEMPERATURES WILL CONTINUE TO MODERATE WITH A LOW-LEVEL
DOWNSLOPE FLOW IN PLACE EAST OF THE FRONT RANGE. WEDNESDAY THROUGH
THURSDAY...FLOW ALOFT TRANSITIONS TO MORE OF A ZONAL COMPONENT
AND WEAK RIPPLES EMBEDDED IN THIS FLOW AND OROGRAPHICS SHOULD
CONTINUE TO PRODUCE PERIODS OF LIGHT SNOW THROUGH THE PERIOD.
AGAIN...ANY SNOW ACCUMULATION SHOULD BE MINOR AND LARGELY CONFINED
TO WEST FACING SLOPES AND TIMBERLINE AREAS.
NEXT...GFS AND ECMWF CONTINUE TO SHOW A LARGE OPEN WAVE TROUGH
FORMING OVER THE GREAT BASIN WEDNESDAY NIGHT AND THURSDAY AND
TRANSLATING EASTWARD ACROSS THE ROCKY MTN REGION THURSDAY NIGHT
AND FRIDAY. ENERGY AND MOISTURE ASSOCIATED WITH THIS WAVE APPEARS
SPLIT WITH PART PASSING OVER WYOMING AND THE OTHER PART OVER
SOUTHERN COLORADO AND NEW MEXICO. HOWEVER THE SOUTHERN BRANCH OF
ENERGY AND MOISTURE IS PROGGED TO LIFT NORTHEAST ACROSS OUR PART
OF THE STATE THURSDAY NIGHT/EARLY FRIDAY MORNING. THIS MAY BE THE
NEXT BEST CHANCE FOR SNOW ACCUMULATION IN THE HIGH COUNTRY THIS
WEEK. WHILE THE PLAINS WILL PROBABLY ESCAPE WITH ONLY A FEW
FLURRIES OR LIGHT SNOW SHOWERS UP AGAINST THE FOOTHILLS AND PALMER
DIVIDE. TEMPERATURES BOTH DAYS ARE EXPECTED TO REMAIN AT OR
SLIGHTLY ABOVE AVERAGE EVEN WITH ALL OF THE CLOUD COVER. BY
SATURDAY...MEDIUM RANGE MODELS SHOW THE TROUGH QUICKLY MOVING OUT
WHICH SETS THE STAGE FOR A WARMING AND GUSTY CHINOOK WIND ALONG
THE FRONT RANGE. SHOULD SEE A NICE REBOUND IN TEMPERATURES OVER
AND EAST OF THE FRONT RANGE THAT DAY UNDER CLEARING SKIES. HIGH
COUNTRY ALSO LOOKS DRY WITH AMPLE SUNSHINE. THEN ON SATURDAY NIGHT
AND SUNDAY...THE NEXT IN THE SERIES OF SYSTEMS ORIGINATING OVER
THE PACIFIC NORTHWEST RACES ACROSS WYOMING AND NORTHERN COLORADO.
LOOKS LIKE ANOTHER SHOT OF SNOW AND GUSTY WINDS FOR THE HIGH
COUNTRY AND GUSTY WINDS AND A SLIGHT CHANCE OF RAIN/SNOW FOR LOWER
ELEVATIONS. MONDAY LOOKS DRIER AND WARMER WITH UPPER RIDGE
BUILDING OVER THE INTERMOUNTAIN WEST.
&&
.AVIATION...NORTHWEST WINDS CURRENTLY SPREADING ACROSS KBJC AND
KDEN WITH SPEEDS AROUND 8 KTS. LIGHT SOUTHEAST WINDS CONTINUING AT
KAPA. LATEST MODELS STILL INDICATING WINDS TO BECOME SOUTHEAST AT
KDEN AROUND 00Z. WILL CONTINUE THIS TREND FOR THE UPCOMING
ISSUANCE. WINDS TO BE MORE WESTERLY AT KBJC WITH SOME GUSTS TO 20
KTS AFTER 06Z. SOME INCREASE IN MID AND HIGH LEVEL CLOUD WITH
POTENTIAL FOR A WAVE CLOUD IN AND NEAR THE FOOTHILLS AFTER 10Z.
CEILINGS TO REMAIN ABOVE 12000 FEET. WINDS TO WEAKEN BY 15Z AND
BECOME SOUTHERLY. MAY BE MORE SOUTHEAST AT KDEN AND KAPA.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...D-L
LONG TERM....BAKER
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1013 AM MST MON JAN 6 2014
.UPDATE...
&&
.SHORT TERM...WIND CHILL ADVISORY ALLOWED TO EXPIRE FOR THE PLAINS
AS TEMPERATURES ARE SLOWLY WARMING. ADVISORY CRITERIA NO LONGER
BEING MET AS WINDS FAIRLY LIGHT. OTHERWISE...CURRENT FORECASTS
LOOK ON TRACK. UPPER JET CURRENTLY OVER REGION WITH FAIRLY STRONG
NORTHWEST FLOW ALOFT. SUBSIDENCE AND DOWNWARD MOTION ON BACK SIDE
OF JET STILL CREATING WINDY CONDITIONS ACROSS THE HIGH ELEVATIONS
AND ALONG THE FOOTHILLS AS WELL AS PORTIONS OF SOUTH PARK. THE
GUSTY WINDS MOST PRONOUNCED ALONG THE LEE OF THE MOSQUITO
RANGE...WITH CURRENT WINDS GUSTING TO 66 MPH AT KENOSHA PASS ALONG
HIGHWAY 285 BETWEEN JEFFERSON AND FAIRPLAY IN PARK COUNTY. THE
GUSTY WINDS MOST LIKELY PRODUCING SOME BLOWING SNOW WITH REDUCED
VISIBILITIES. JET WILL CONTINUE TO MOVE EAST DURING THE DAY WITH
FLOW ALOFT BECOMING WESTERLY. THOUGH GRADIENT EXPECTED TO
WEAKEN...MOUNTAIN WAVE WILL STILL PERSIST FOR MUCH OF THE
AFTERNOON. GUSTY WINDS TO CONTINUE ACROSS THE MOUNTAINS...
FOOTHILLS AND SOUTH PARK AS WELL AS THE NEARBY PLAINS. SPEEDS
SHOULD NOT BE AS STRONG AS CURRENTLY BEING OBSERVED. BLOWING SNOW
WILL STILL BE A POSSIBILITY IN OPEN AREAS. WILL LOWER MAX TEMPS A
BIT IN THE LOW LYING AREAS ALONG THE SOUTH PLATTE RIVER NORTH OF
DENVER AS TEMPERATURES STILL AT ZERO OR SLIGHTLY BELOW AND MAY
STRUGGLE TO REACH 20 DEGREES.
.AVIATION...CURRENT TAF TRENDS LOOK REASONABLE. FAIRLY STRONG
NORTHWEST FLOW ALOFT TO GRADUALLY WEAKEN THROUGH THE
DAY...BECOMING MORE WESTERLY. LATEST MODELS CONTINUE TO KEEP
SOUTHEAST WINDS AT KDEN AND KAPA WHILE REMAINING WESTERLY AT KBJC.
ENOUGH SHEAR IN PLACE TO KEEP LLWS GOING AT KDEN THROUGH 20Z.
&&
.PREV DISCUSSION... /ISSUED 329 AM MST MON JAN 6 2014/
SHORT TERM...STRONG UPPER LEVEL JET IS MOVING OVERHEAD AT THIS
TIME CREATING SOME LOCALIZED VERY WINDY CONDITIONS IN THE HIGH
ELEVATIONS AND PARTS OF SOUTH PARK IN THE LEE OF THE MOSQUITO
RANGE. THERE IS LIKELY SOME BLOWING SNOW IN THESE AREAS AS WELL.
AS THE JET PUSHES EASTWARD WITH THE UPPER RIDGE COMING OUR WAY
THESE VERY STRONG WINDS SHOULD SETTLE DOWN BUT IT WILL REMAIN
RELATIVELY WINDY UP HIGH THROUGH THE PERIOD. WITH THE FLOW ALOFT
BECOMING A BIT MORE WESTERLY MOUNTAIN WAVE ACTIVITY WILL BRING
GUSTY WINDS TO SOME FOOTHILL LOCATIONS AS WELL AS AREAS RIGHT UP
AGAINST THE FOOTHILLS LATER IN THE DAY. THE HRRR SEEMS TO HAVE A
DECENT GRASP ON THIS SITUATION. ANY SPOTS THAT SEE THE GUSTY WINDS
WILL ALSO BE PRONE TO BLOWING AND DRIFTING SNOW AND ASSOCIATED
LOWERED VISIBILITIES. THERE WILL BE A FEW SNOW SHOWERS OVER THE
HIGHER MOUNTAINS THIS MORNING ALONG WITH SOME PATCHY FOG OVER THE
PLAINS. ASIDE FROM THESE PHENOMENA WEATHER NIL. WILL LET THE WIND
CHILL ADVISORY GO AS IS...EXPIRING AT 0800 MST. HIGH TEMPERATURES
WILL REMAIN BELOW NORMAL TODAY BUT WILL PROBABLY BE SOME 15 TO 20
DEGREES ABOVE THOSE EXPERIENCED SUNDAY. MINIMA TONIGHT WILL ALSO
BE QUITE A BIT WARMER THAN WHAT IS OCCURRING PRESENTLY. PLENTY OF
SUNSHINE TODAY AND GENERALLY CLEAR SKIES TONIGHT ASIDE FROM THE
WAVE CLOUDS SHOWN IN THE CIRA SYNTHETIC SATELLITE IMAGERY. THESE
BECOME RATHER EXTENSIVE OVER THE FOOTHILLS BY 12Z TUESDAY.
LONG TERM...MODELS HAVE MODERATE WEST-NORTHWESTERLY FLOW ALOFT FOR
THE FORECAST AREA TUESDAY THROUGH WEDNESDAY NIGHT. A WEAK TROUGH
MOVES ACROSS IN THE FLOW TUESDAY AFTERNOON AND EVENING. THEN
ANOTHER WEAK ONE LATER ON WEDNESDAY. NOTHING SIGNIFICANT...PERHAPS
A SPOT OF SNOW FOR THE MOUNTAINS. THERE IS ASCENT PROGGED
ACCORDING TO THE QG VERTICAL VELOCITY FIELDS FOR THE CWA ON
TUESDAY...THEN DOWNWARD MOTION TUESDAY NIGHT. WEDNESDAY`S SYNOPTIC
SCALE ENERGY IS PRETTY BENIGN. SOME OF THE MODELS SHOW WEAK LOW
LEVEL UPSLOPE FOR THE PLAINS TUESDAY AFTERNOON AND EVENING.
WEDNESDAY`S WINDS LOOK PRETTY WEAK...WITH MAYBE SOME DOWNSLOPING
TO ENHANCE THE NORMAL DRAINAGE PATTERNS WEDNESDAY NIGHT. FOR
MOISTURE...MODELS SHOW QUITE A BIT IN THE MID AND UPPER LEVELS
FROM MIDDAY TUESDAY THROUGH WEDNEDAY AFTERNOON. THE MOISTURE IS
PRETTY DEEP OVER THE MOUNTAINS TUESDAY NIGHT WELL INTO WEDNESDAY.
THIS MORE SO ON THE GFS. MODELS HAVE LIMITED MEASURABLE SNOWFALL
OVER THE MOUNTAINS TUESDAY EVENING INTO WEDNESDAY EVENING
ACCORDING TO THE QPF FIELDS. FOR POPS...WILL KEEP IN OR GO WITH
20-50%S IN THE MOUNTAINS AND HIGH VALLEYS...SAVE PARK COUNTY
..FROM TUESDAY NIGHT THROUGH WEDNESDAY EVENING. WILL DECREASE
MOUNTAIN POPS WEDNESDAY NIGHT AFTER MIDNIGHT. NO POPS FOR THE
PLAINS OR FOOTHILLS. FOR TEMPERATURES...TUESDAY`S HIGHS ARE
PROGGED TO 6-11 C WARMER THAN TODAY`S. WEDNESDAY`S COOL DOWN A
BIT...SOME 2.0-3.5 C FROM TUESDAY`S. FOR THE LATER DAYS...
THURSDAY THROUGH SUNDAY...MODELS KEEP MORE OF THE SAME GOING. THEY
HAVE A WEAK UPPER TROUGH MOVE ACROSS THURSDAY MORNING...BUT A
STRONGER ONE ON FRIDAY...WHICH THE ECMWF IS A PERIOD QUICKER WITH.
THERE ARE STRONG NORTH TO NORTHWEST UPPER LEVEL WINDS BEHIND THE
TROUGH...AGAIN WHICH THE ECMWF IS EARLIER WITH. BY SUNDAY...BOTH
MODELS ARE SHOWING A MORE SIGNIFICANT UPPER TROUGH GETTING INTO
COLORADO. IT BEARS WATCHING. WILL HAVE "CHANCE" POPS IN THE
MOUNTAINS FRIDAY INTO FRIDAY NIGHT. WILL GO SOME LIMITED POPS FOR
ALL THE CWA ON SUNDAY. TEMPERATURES LOOK TO HOVER NEAR NORMALS
MUCH OF THE TIME.
AVIATION...THERE MAY BE SOME PATCHES OF FOG FLOATING ABOUT UNTIL
MID MORNING WHICH COULD CREATE LIFR CONDITIONS FOR A TIME. ASIDE
FROM THAT VFR CONDITIONS ARE EXPECTED THROUGH TONIGHT. WINDS WILL
BE GENERALLY LESS THAN 10 KNOTS AND FAVORING A SOUTHEASTERLY
DIRECTION BY AFTERNOON AT KDEN AND KAPA WHEREAS KBJC WILL BEGIN
COMING UNDER THE INFLUENCE OF MOUNTAIN WAVE/LEE TROUGH ACTIVITY
KEEPING THE WINDS OUT OF THE WEST. THEY COULD ALSO SEE SOME GUSTS
INTO THE 20S BY AFTERNOON.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...D-L
LONG TERM....RJK
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1244 PM EST MON JAN 6 2014
.SYNOPSIS...
MILD WEATHER ALONG WITH PERIODS OF RAIN SHOWERS AND AREAS FOG ARE
EXPECTED TODAY AHEAD OF A STRONG COLD FRONT. A SHOT OF ARCTIC AIR
ARRIVES TONIGHT AND CONTINUES INTO WED BEHIND THE FRONT. MILDER
WEATHER RETURNS FRI INTO SAT WITH PERHAPS A PERIOD OF LIGHT
PRECIPITATION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1 PM UPDATE...
ARCTIC COLD FRONT PRESENTLY ACROSS CENTRAL NEW ENGLAND.
OUT AHEAD...WIDESPREAD RAIN WITH EMBEDDED HEAVIER SHOWERS...
CONTINUED SOUTHERLY FLOW AND AREAS OF FOG DOWN TO A QUARTER MILE
OR LESS. GUSTY WINDS UP TO 40 MPH POSSIBLE AS THE COMBINATION OF
WARMER TEMPERATURES AND HEAVIER RAIN ALLOW FOR THE MIX-DOWN OF
MOMENTUM TO THE SURFACE. BELIEVE THERE IS NO LONGER A THREAT FOR
THUNDER.
BEHIND...TEMPERATURES DROPPING QUICKLY TO WHICH MODELS ARE HAVING
SOMEWHAT OF A DIFFICULT TIME CATCHING UP ON. BEST GUIDANCE IS ON
THE HRRR THOUGH ITS DELAY DOES NOT CAPTURE THE PRESENT COLD
TEMPERATURES AND SNOW OVER ALBANY. IT IS LIKELY THE FORECAST DOES
NOT MERIT THE OUTCOME. RATHER IT BEARS WATCHING THE SLUG OF
PRECIPITATION OVERSPREADING WESTERN NEW ENGLAND OVERSPREADING THE
COLDER AIR SLIDING IN UNDERNEATH. ALREADY REPORTS OF SNOW OVER THE
BERKSHIRES HAS BEEN GATHERED AND AS THE SYSTEM LIFTS OUT IT IS
LIKELY WE WILL SEE SOME SNOW ON THE BACKSIDE FOR WESTERN AND
CENTRAL PORTIONS OF NEW ENGLAND. WILL DO THE BEST TO MODIFY THE
FORECAST TO ACCOUNT FOR TRENDS. WESTERLY FLOW IMMEDIATELY BEHIND
THE FRONT GUSTY UP TO AROUND 30 TO 40 MPH. MID-LEVEL CLOUDS
LINGERING WITH BOUNDARY LAYER MIXING UP TO H8 OF RESIDUAL
MOISTURE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
A SHOT OF ARCTIC AIR WILL BE WORKING INTO THE REGION TONIGHT. WHILE
IT CERTAINLY WILL BECOME VERY COLD...WE WON/T BE DEALING WITH THE
EXTREME BITTERLY COLD AIR AFFECTING THE MIDWEST. THIS SHOT OF
ARCTIC AIR WILL ATTACK US FROM THE WEST AND SOUTHWEST...WHICH IS
NOT A CLASSIC TRAJECTORY FOR SOUTHERN NEW ENGLAND. ITS MOST POTENT
FOR OUR REGION WHEN IT COMES FROM THE NORTH AND NORTHWEST.
NONETHELESS...IT WILL BE QUITE COLD AND WINDY TONIGHT. LOW TEMPS
BY DAYBREAK WILL BE WELL DOWN INTO THE TEENS IN MOST LOCATIONS AND
IT WILL BE BREEZY TO WINDY. THIS WILL RESULT IN WIND CHILL VALUES
BETWEEN 0 AND 10 BELOW BY DAYBREAK!
AS FOR PRECIP CHANCES...THE SHOT OF ARCTIC AIR WILL BE ACCOMPANIED
BY A STRONG UPPER LEVEL SHORTWAVE. THERE SHOULD BE ENOUGH FORCING
WITH THE UPPER LEVEL TROUGH TO GENERATE A FEW BRIEF SNOW SHOWERS
AND PERHAPS A HEAVIER SQUALL OR TWO. CAN/T RULE OUT A FEW
NEIGHBORHOODS RECEIVING A COATING TO 1 INCH OF SNOW...WHILE OTHER
AREAS DO NOT SEE ANYTHING.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
HIGHLIGHTS...
* ANOTHER ROUND OF ARCTIC AIR AND HIGH PRESSURE TUESDAY INTO WED
* OCEAN EFFECT SNOW SHOWERS FOR THE ISLAND AND CAPE ON TUESDAY
* FLURRIES/SNOW SHOWERS POSSIBLE THURSDAY INTO FRIDAY
* WARMING TREND FOR NEXT WEEKEND
CONFIDENCE LEVEL/MODEL PREFERENCE...
HIGH CONFIDENCE IN STRONG ARCTIC AIR INTRUDING INTO THE REGION
TUESDAY INTO WEDNESDAY AS WELL AS OCEAN EFFECT SNOW SHOWERS FOR
THE WATERS. MODERATE CONFIDENCE ON AN OVERRUNING SYSTEM
THURSDAY/FRIDAY....UNCERTAIN ON TIMING AND PTYPE. RISING HEIGHTS
WILL LEAD TO A WARMING TREND FOR THE WEEKEND...MODERATE
CONFIDENCE. OTHERWISE LOW CONFIDENCE ON POSSIBLE SYSTEMS FOR THE
WEEKEND INTO NEXT WEEK AS THERE IS A LOT OF MODEL VARIABILITY.
OVERALL....
00Z MODEL GUIDANCE IS IN GOOD AGREEMENT IN ANOMALOUS TROUGH OVER
THE REGION ON TUESDAY AND PUSH INTO A MORE ZONAL FLOW BY
WED/THURSDAY. MID-ATLANTIC HIGH PRESSURE WILL BEGIN TO BUILD
WITHIN THE ZONAL FLOW...WITH THE EC SHOWING A MUCH STRONGER HIGH
THAN THE GFS. MODELS CONTINUE TO SHOW A WEAK RIPPLE IN THE
NORTHERN STREAM THAT WILL PUSH THE HIGH OFFSHORE LATE THURSDAY AND
ALLOW FOR A WEAK DISTURBANCE ON FRIDAY WITH THE EC SLIGHTLY SLOWER
THEN THE GFS. HOWEVER BOTH MODELS INDICATE A BUILDING RIDGE FOR
THE WEEKEND AHEAD OF SEVERAL SYSTEMS BY EARLY NEXT WEEK...STILL A
LOT OF TIMING DIFFERENCES AMONGST THE MODELS AND ENSEMBLES.
DETAILS...
TUESDAY INTO WEDNESDAY NIGHT...
ANOMALOUS TROUGH WITH SEVERAL EMBEDDED WAVES WILL CONTINUE TO
REMAIN OVER THE REGION TUESDAY INTO WEDNESDAY. THIS WILL KEEP THE
STRONG ARCTIC AIR IN SOUTHERN NEW ENGLAND RESULTING IN HIGH TEMPS
IN THE TEENS AND TWENTIES. ONE OF THESE WAVES WILL MOVE THROUGH
DURING THE DAY ON TUESDAY ALLOWING FOR POSSIBLE 30-40KTS AT 850MB
TO MIX DOWN AND CREATE BLUSTERY CONDITIONS. THERE IS A
POSSIBILITY THAT A WIND ADV MAY BE NEEDED ACROSS THE ISLANDS AS
THIS STRONG ARCTIC AIR WILL ALLOW FOR GOOD MIXING ALOFT...ALMOST
ABOVE 800MB. BECAUSE OF THE STRONG WINDS...COMBINED WITH ARCTIC
AIR APPEARS THAT WIND CHILL ADVISORIES MAY BE NEEDED ESP FOR
WESTERN/CENTRAL MASS ON TUESDAY NIGHT. DUE TO STRONG WESTERLY FLOW
ON TUESDAY...THERE IS AN INCREASING POSSIBILITY THAT A BAND OR TWO
FROM THE LES EVENT COULD MAKE ITS WAY INTO THE BERKS AND PERHAPS
INTO THE CENTRAL HILLS. INCREASED POPS FOR TUESDAY MORNING AND
MENTIONED ISOLATED SNOW SHOWERS...BUT IT WILL ALL BE DEPENDENT ON
WHERE EXACTLY THE BAND SETS UP AND HOW STRONG THE FLOW IS.
THE OTHER POTENTIAL IS THE POSSIBILITY OF OCEAN EFFECT SNOW SHOWERS
TO ACCUMULATE ACROSS ACK/BID AND PERHAPS THE OUTER CAPE. THIS VERY
COLD ARCTIC AIR ALOFT WILL MOVE OVER THE RELATIVELY WARM WATERS
AND CREATE A 850MB TEMPS SPREAD OF OVER 20C. MODELS ALSO INDICATE
LIC OVER OVER 600 J/KG AND VERY STEEP LAPSE RATES. DEPENDING ON
THE WIND DIRECTIONS ACK AND SOUTHERN SHORE OF RI MAY SEE
ACCUMULATING SNOW FALL. RI CHANCE IS IF A LONG ISLAND SOUND BAND
SETS UP. THE BEST CHANCE FOR THIS TO OCCUR IS WITH A MORE SW
FLOW...BUT IF THE 850MB TO SURFACE FLOW IS MORE WEST THEN
EXPECTED...PERHAPS A DUSTING IS MORE LIKELY. RIGHT NOW APPEARS
THAT A COATING TO LESS THAN AN INCH IS POSSIBLE...HOWEVER IF THE
FLOW BACKS AT ALL THEN 1-2 INCHES MAY OCCUR DEPENDING ON WHERE THE
BANDS SET UP.
THURSDAY AND FRIDAY...
HIGH PRESSURE WILL INTRUDE INTO THE REGION LATE WEDNESDAY INTO
THURSDAY RESULTING IN A WARMUP/CLOSER TO AVERAGE FOR THE REGION.
GFS AND EC DEVELOP A WEAK SYSTEM OVER THE MIDWEST LATE THURSDAY
INTO FRIDAY. APPEARS THAT THERE IS SOME OVERRUNING OF PRECIP AND
WITH THE SW FLOW OVER THE HIGH PRESSURE...COULD SEE SOME SNOW
SHOWERS AS IT WILL TAKE SOME TIME FOR THE WARM AIR TO PUSH THIS
COLD AIR OUT OF THE REGION. STILL A LOT OF UNCERTAINTY WITH THIS
POTENTIAL AS THE GFS WARMS UP VERY QUICKLY ON FRIDAY BUT BRINGS A
GOOD SWATH OF PRECIP WHILE THE EC HAS LESS PRECIP AND WONT WARM UP
TIL LATE FRIDAY NIGHT. REGARDLESS HAVE INCREASING CONFIDENCE IN
NEAR AVG TEMPS AND PRECIP LATE THURSDAY INTO FRIDAY.
WEEKEND...
RIDGING ALOFT INDICATES A JANUARY THAW FOR THE REGION AS HIGH
TEMPS WILL REACH INTO THE 40S TO 50S. MODELS INDICATE THAT SEVERAL
UPPER LEVEL DISTURBANCES WILL APPROACH THE REGION LATE WEEKEND
INTO NEXT WEEK. A LOT OF UNCERTAINTY REGARDING EXACT TIMING AND
PTYPE. LOOKS AS IF WE WILL BE ON THE WARMER SIDES OF THESE
SYSTEMS.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /TODAY THROUGH MONDAY/...
18Z UPDATE...
IFR-VLIFR SOUP REMAINING MAINLY OVER E NEW ENGLAND TERMINALS FOR
THE NEXT HR OR TWO AS THE COLD FRONT PRESENTLY OVER CENTRAL NEW
ENGLAND SWINGS E. VSBYS DOWN TO A QUARTER MILE. LLWS AROUND 210 AT
60 KTS AT 2 KFT WITH S WINDS AT THE SURFACE GUSTING UP TO 40 KTS.
WIDESPREAD RAIN +RA AT TIMES.
BEHIND THE FRONT...IMMEDIATE IMPROVEMENT TO VFR. W WINDS GUSTING
UP TO 35 KTS. CIGS LIFTING. EXPECTING W WINDS TO CONTINUE THROUGH
THE ENTIRE FORECAST PERIOD...GUSTS UP TO 40 KTS AT TIMES...WITH
SCT- BKN LOW- END VFR MAINLY OVER THE INTERIOR...WITH SCT-BKN MVFR
CIGS ALONG THE SHORES AND DEFINITELY OVER PORTIONS OF THE CAPE AND
ISLANDS. WINDS DIMINISHING TOWARDS WEDNESDAY MORNING.
KBOS TAF...HIGH CONFIDENCE IN TAF.
KBDL TAF...HIGH CONFIDENCE IN TAF.
OUTLOOK...WEDNESDAY THROUGH FRIDAY...MODERATE CONFIDENCE
WEDNESDAY THROUGH FRIDAY... VFR WEDNESDAY AND THURSDAY. AREAS OF
MVFR CIGS/VSBYS IN RAIN/SNOW SHOWERS THURSDAY NIGHT AND FRIDAY.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
NEAR TERM /TODAY AND TONIGHT/...MODERATE TO HIGH CONFIDENCE.
TODAY...SOUTHERLY FLOW INCREASING THIS MORNING AS LOW LEVEL JET
INTENSIFIES AHEAD OF AN APPROACHING COLD FRONT. LONG SOUTHERLY
FETCH HAS ALREADY ALLOWED SEAS TO BUILD TO SCA LEVELS ACROSS THE
OPEN WATERS ALONG WITH 20 TO 25 KNOT WIND GUSTS. IN
ADDITION...AREAS OF FOG WILL BE LOCALLY DENSE AT TIMES AND CAN/T
RULE OUT A RUMBLE OR TWO OF THUNDER.
TONIGHT...STRONG COLD ADVECTION BEHIND THE FRONT WILL RESULT IN
WESTERLY WIND GUSTS INCREASING TO AROUND 35 KNOTS. GALE WARNINGS
ISSUED FOR ALL WATERS...ALTHOUGH SOME WATERS MAY NOT SEE WINDS
INCREASE TO GALE LEVELS UNTIL DAYBREAK TUE. IN ADDITION...WE HAVE
ISSUED A FREEZING SPRAY ADVISORY FOR MOST OPEN WATERS BEGINNING AT
10Z TUESDAY AND CONTINUING THROUGH WED MORNING. STRONG WINDS AND
VERY COLD AIR WILL LEAD TO AREAS OF MODERATE FREEZING SPRAY OVER
THIS TIME.
OUTLOOK...TUESDAY THROUGH FRIDAY...MODERATE CONFIDENCE.
TUESDAY...WEST GALES CONTINUING WITH WINDS REACHING 35-40 KNOTS.
STRONGEST WINDS WILL BE ON TUESDAY. SEAS WILL BUILD TO 6-12 FEET
ON THE EXPOSED WATERS. A GALE WARNING HAS BEEN ISSUED FOR ALL THE
WATERS. EXPECT MODERATE FREEZING SPRAY ACROSS THE WATERS.
WEDNESDAY THROUGH FRIDAY...RESIDUAL WEST WINDS AROUND 25 KNOTS
WEDNESDAY...DIMINISHING WEDNESDAY NIGHT. WINDS REMAIN BELOW 25
KNOTS THROUGH FRIDAY. LEFTOVER 5-7 FOOT SEAS WEDNESDAY SUBSIDE BY
EVENING AND REMAIN BELOW 5 FEET THURSDAY-FRIDAY. POSSIBLE REDUCED
VSBYS IN RAIN/SNOW SHOWERS THURSDAY NIGHT AND FRIDAY.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...DENSE FOG ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR
MAZ005>007-013>021.
DENSE FOG ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
MAZ022>024.
NH...DENSE FOG ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR NHZ012.
RI...DENSE FOG ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR RIZ005-
007.
MARINE...FREEZING SPRAY ADVISORY FROM 5 AM TUESDAY TO 1 PM EST
WEDNESDAY FOR ANZ231-232-235-237-250-251-254>256.
GALE WARNING FROM MIDNIGHT TONIGHT TO 9 PM EST TUESDAY FOR
ANZ231>234.
GALE WARNING FROM 7 AM TO 6 PM EST TUESDAY FOR ANZ230-236.
GALE WARNING FROM 10 PM THIS EVENING TO 1 AM EST WEDNESDAY FOR
ANZ235-237-254>256.
GALE WARNING FROM MIDNIGHT TONIGHT TO 1 AM EST WEDNESDAY FOR
ANZ250-251.
&&
$$
SYNOPSIS...FRANK/DUNTEN
NEAR TERM...SIPPRELL
SHORT TERM...FRANK
LONG TERM...DUNTEN
AVIATION...DUNTEN/SIPPRELL
MARINE...FRANK/DUNTEN
AREA FORECAST DISCUSSION
NWS CARIBOU ME
308 PM EST MON JAN 6 2014
.SYNOPSIS...
STRONG LOW PRESSURE WILL TRACK WEST OF MAINE THIS AFTERNOON. MUCH COLDER
AIR WILL SWEEP BACK INTO THE AREA BEHIND THIS SYSTEM TONIGHT AND REMAIN
INTO LATE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
COLDER TEMPERATURES, FOG AND RE-FREEZING OF THE STANDING WATER THE
MAIN CONCERN FOR TONIGHT. THIS HAS LED TO SOME HYDROLOGY CONCERNS
WHICH ARE ADDRESSED IN THE LAST PARAGRAPH.
STRONG COLD FRONT WILL SWEEP ACROSS THE REGION TONIGHT USHERING IN
ANOTHER ROUND OF ARCTIC AIR. WARMER AIR W/RAIN OUT AHEAD OF THE
FRONT WILL BEGIN TO PUSH E THIS EVENING W/TEMPERATURES FALLING
BACK IN WESTERN MAINE LATER THIS AFTERNOON AND THEN REACHING
EASTERN AND NE AREAS AFTER 00Z. RAIN WILL GO TO A PERIOD OF SNOW
BEFORE ENDING AND THIS WILL MAINLY BE ACROSS THE FAR NORTHERN AND
WESTERN AREAS. ANY SNOW ACCUMULATIONS WILL BE LESS THAN AN INCH.
THE LATEST RUN OF THE HRRR WAS DOING REMARKABLY WELL W/THE RAINFALL
AND TEMPERATURES AND FOLLOWED ITS TREND INTO THE NIGHTTIME HOURS.
PRECIP SHOULD END FOR THE ENTIRE CWA BY MIDNIGHT W/PARTIAL CLEARING
THAT COLD AIR PUSHING IN. THE TEMPERATURES WILL REALLY PLUMMET
AFTER MIDNIGHT AS THE ARCTIC TAKES HOLD. READINGS BY EARLY MORNING
ON TUESDAY WILL BE IN THE SINGLE NUMBERS ACROSS NORTHERN AREAS
W/SOME LOCATIONS AOB ZERO ESPECIALLY IN WESTERN AND NORTHWEST
AREAS. ACROSS THE CENTRAL HIGHLANDS AND DOWNEAST, READINGS ARE
EXPECTED TO BE IN THE LOWER TEENS.
THIS COLDER AIR WILL ALLOW FOR THE SETUP FOR A FLASH FREEZE OR A
RE-FREEZE OF ANY STANDING WATER OVERNIGHT. THIS WILL LEAD TO
SLIPPERY ROAD CONDITIONS IN SOME LOCATIONS. A SPECIAL WEATHER
STATEMENT WILL BE ISSUED TO ADDRESS THIS SITUATION.
FOG WILL BE A CONCERN INTO THE EVENING ESPECIALLY ACROSS DOWNEAST
AND THE COAST. VSBYS DOWN ON THE COAST HAVE BEEN AROUND 1/4 OF A
MILE OR LOWER AT TIMES AND RUNNING FROM 1/2 TO 1/4 OF A MILE IN
THE BANGOR AREA. DECIDED TO KEEP WIDESPREAD FOG IN THESE AREAS THROUGH
EARLY EVENING AND ONCE THE COLDER AIR BEGINS TO FILTER IN AND
WINDS TURN WNW, CONDITIONS WILL IMPROVE. FOG ACROSS NORTHERN MAINE
FOR A TIME THIS EVENING BUT IT WILL BE SHORT LIVED.
AS FOR THE WINDS, THE STRONG WINDS THAT OCCURRED EARLIER TODAY
HAVE SINCE ABATED AS THE STRONG LLVL JET(55 KTS) HAS PUSHED TO THE
EAST INTO NEW BRUNSWICK. THEREFORE, THE WIND HEADLINES HAVE BEEN DROPPED.
LASTLY, THERE HAS BEEN CONCERN W/SOME PONDING OF WATER ON AREA
ROADS DUE TO THE SNOWMELT AND RAIN W/SOME STORM DRAINS CLOGGING
LEADING TO MINOR STREET FLOODING. A SURGE UP THE PENOBSCOT RIVER
NEAR BANGOR HAS LED THE CITY OF BANGOR TO CLOSE THE KENDUSKEAG
PLAZA PARKING GARAGE. THE LATEST GAGE HEIGHT WAS JUST AT 11.0 FT
WHICH IS CLOSE TO ACTION STAGE. A FLOOD ADVISORY WAS ISSUED
EARLIER FOR THIS AREA TO ACCOUNT FOR THE PLAY IN THE SURGE AND
REMAINS UP THROUGH THIS EVENING.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
EXPECT STRONG COLD ADVECTION DURING THE DAY TUESDAY AS INTENSE
LOW PRESSURE OVER NORTHEAST CANADA IN CONJUNCTION WITH STRONG HIGH
PRESSURE OVER THE SOUTH GENERATES A STRONG FLOW FROM THE
NORTHWEST. EXPECT THIS PATTERN TO PERSIST INTO WEDNESDAY THEN
MODERATE AS HIGH PRESSURE BUILDS IN FROM THE WEST DURING THE DAY
THURSDAY THEN CRESTS OVER THE REGION THURSDAY NIGHT. FOR POPS AND
QPF WILL USE A BLEND OF THE NAM12 ...GFS40 ...SREF AND ECMWF. FOR
WINDS HAVE USED THE MOSG25. THE TEMPERATURE GRIDS GENERATED WITH
THE RAW BLEND DUE TO THE EXPECTED CHANGE IN AIRMASS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
MILD AND RELATIVELY UNSETTLED LATE THIS WEEK INTO EARLY NEXT WEEK.
HIGH PRESSURE OVERHEAD THURSDAY NIGHT WILL SHIFT TO OUR EAST
FRIDAY INTO SATURDAY, AND WITH THIS WILL COME A WARMER SOUTHWEST
FLOW. THERE LOOKS TO BE A DECENT CHANCE OF PRECIPITATION SATURDAY
AND SATURDAY NIGHT. TEMPERATURES WILL BE WARM ENOUGH FOR MIXED
PRECIPITATION FOR MOST OF THE AREA. TEMPERATURES COOL OFF A BIT
BEHIND THE SYSTEM SUNDAY/SUNDAY NIGHT, BUT NOT EVEN CLOSE TO THE
ARCTIC CHILL WE HAVE BEEN SEEING. THIS LOOKS TO CONTINUE THROUGH
ALL OF NEXT WEEK...A WARMER WEATHER PATTERN WITH FAIRLY WEAK
SYSTEMS IN WHICH WE WILL BE DEALING WITH PRECIPITATION TYPE
CHALLENGES.
MODELS ARE IN FAIRLY GOOD AGREEMENT THURSDAY NIGHT INTO THE
WEEKEND. SOME SLIGHT TIMING ISSUES WITH THE WEEKEND SYSTEM, BUT
NOTHING MAJOR. TIMING OF SYSTEMS INTO EARLY NEXT WEEK BECOMES
SIGNIFICANTLY MORE DIFFICULT.
&&
.AVIATION /19Z MONDAY THROUGH SATURDAY/...
NEAR TERM: IFR/LIFR ATTM ACROSS THE TERMINALS. CONDITIONS ARE EXPECTED
TO IMPROVE MVFR LATER THIS EVENING AND THEN VFR AFTER MIDNIGHT W/A
WNW WIND TAKING OVER AND COLDER AIR MOVING IN.
SHORT TERM: EXPECT VFR CONDITIONS TUESDAY THROUGH THURSDAY.
&&
.MARINE...
NEAR TERM: LOWERED THE GALE WARNING TO A SCA AS WINDS HAVE COME
DOWN BELOW GALE FORCE. CARRIED GUSTS TO 30 KTS THIS EVENING W/A
FEW GUSTS TO 35 KTS POSSIBLE. WINDS ARE EXPECTED TO COME BACK UP
ON TUESDAY W/THE NW WIND AND SURGE OF CAA OVER THE RELATIVELY
WARMER OCEAN WATERS. WHEN ABOVE THE GUIDANCE ON THE WAVE HEIGHTS
EARLY TONIGHT BY 1-2 FT. A 8-9 SECOND PERIOD SWELL IS THERE ADDING
TO THE WAVE HEIGHTS. WAVE HEIGHTS WILL START TO FALL BACK EARLY
TUESDAY MORNING AS THE WIND BECOMES OFFSHORE.
SHORT TERM: FOR WIND HAVE BLENDED THE NAM12 AND GFS40. FOR WAVES:
LONG FETCH FROM THE GULF OF MAINE SOUTHWARD WILL PERSIST UNTIL IT
IS BROKEN UP BY THE WIND SHIFT LATER TONIGHT. PRIMARY WAVE GROUP
TUESDAY WILL BE FROM THIS FETCH ...6-10 FEET/10-11 SECONDS. EXPECT
THIS LONG PERIOD WAVE GROUP TO PERSIST INTO THURSDAY DUE TO THE
LENGTH OF THE FETCH. WILL USE THE SWAN/NAM TO GENERATE WAVE GRIDS.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EST TUESDAY FOR ANZ050>052.
&&
$$
NEAR TERM...HEWITT/NORTON
SHORT TERM...MIGNONE
LONG TERM...FOISY
AVIATION...HEWITT/MIGNONE
MARINE...HEWITT/MIGNONE
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
525 PM EST MON JAN 6 2014
.SYNOPSIS...
THE ARCTIC AIRMASS OVER THE UPPER OHIO VALLEY REGION WILL MODERATE
QUICKLY DURING THE SECOND HALF OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
EARLY EVE UPDATE WAS ISSUED TO DROP THE WINTER WEATHER ADVISORY
FOR THE RIDGE ZONES AS ADDITIONAL SNOW ACCUMULATION WL BE MINOR
AND AREAS OF BLOWING SNOW WL LIKELY CAUSE ONLY LOCALIZED ISSUES.
OTHERWISE...HAVE ADJUSTED POPS AND SFC WIND BASED ON THE LATEST
OBS...RADAR...AND DETERMINISTIC MDL TRENDS. HAVE DIMINISHED GUSTS
MAINLY OVR THE RIDGES AS PER LATEST RAP AND NAM MOMEMTUM TRANSFER
PROGNOSIS...AS INVERSION LVLS WL LIKELY PREVENT DEEP MIXING OF
HIGHER WIND VALUES.
IN GENL...SUB ZERO AIR WL CONT TO SLIDE OVR THE REGION AS THE EVE
PROGRESSES...HENCE MOST DETAIL CHANGES ARE COSMETIC AND WIND CHILL
WARNING CONTS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
DRY AND COLD CONDITIONS WL PREVAIL THROUGH THROUGH TUESDAY NGT AND
WIND CHILL WARNING WAS CONTD FOR NOW. ALTHOUGH DIMINISHING WIND
AND WARM ADVCTN MAY PREVENT ACTUAL CRITERIA FM BEING REACHED AFTR
DARK ON TUESDAY...NO POINT TO HEADLINE ALTERATION AT THIS TIME.
THAT WARM ADVECTION REGIME WL INTENSIFY AND RTN TEMPS TWD THE
SEASONAL AVGS AS A SHRTWV IS PROJECTED ACRS THE GREAT LAKES ON
WED...WHILE ANOTHER IS PROGGED OUT OF THE LOWER OHIO ON THURSDAY.
SNOW CHCS HAVE BEEN MAINTAINED FOR THOSE FEATURES.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
MODELS REMAIN CONSISTENT IN BRINGING A SHORTWAVE TROUGH AT 500MB
ACROSS REGION THURSDAY NIGHT. UPPED POPS TO COINCIDE WITH THIS
FEATURE AND QUICKLY PUSH THE FOCUS OF THESE CHC POPS EAST...DRYING
BEHIND IT. NOT ALTERING THE TEMPERATURES MUCH THURS AND FRI
MORNING...SO A PRIMARILY SNOW PTYPE EVENT REMAINS THE THINKING.
SIGNIFICANT WARM UP PROGGED FOR THE WEEKEND AS RIDGING TAKES PLACE
BEHIND EXITING SHORTWAVE. 850MB TEMPS REBOUND FROM NEAR FREEZING TO
8 TO 10C SAT ON THE GFS. BUMPED UP TEMPERATURES A FEW DEGREES ACROSS
THE BOARD AS WE GO ABOVE AVERAGE FOR THIS TIME OF YEAR. A WELCOMED
CHANGE BY MOST FROM THE COLD OF THE LAST WEEK. ANOTHER QUICK MOVING
SYSTEM IS POISED TO MOVE THROUGH SAT...BUT ONLY MODEST CAA BEHIND IT
KEEPS OUR TEMPERATURES FROM FALLING OFF DRAMATICALLY. ANOTHER SYSTEM
APPROACHES FROM THE SOUTH TO START NEXT WORK WEEK...BUT CONSIDERABLE
TIMING AND STRUCTURE DIFFERENCES EXIST ON HOW TO HANDLE THE SOUTHERN
CUTOFF TRACKING ACROSS THE SOUTHEAST.
&&
.AVIATION /22Z MONDAY THROUGH SATURDAY/...
ALTHOUGH GENERAL VFR WL RTN THIS EVENING AND CONT INTO TUESDAY...SFC
WIND WL RMN AN AVIATION CONCERN WITH GUSTS TO ARND 25 KT CONTG.
.OUTLOOK.../MONDAY NIGHT THROUGH FRIDAY/...
THE NEXT CHANCE FOR RESTRICTIONS WL COME WITH CROSSING DISTURBANCES
ON WEDNESDAY AND THURSDAY.
&&
.CLIMATE...
A SUMMARY OF SIGNIFICANT COLD TEMPERATURE READINGS IS INCLUDED
BELOW...
CITY MON/TUE LAST DATE LAST DATE LAST DATE
RECORD(YEAR) BELOW -10 BELOW 0 HIGH BELOW 0
PITTSBURGH -5(1942)/-5(1884) 1/17/2009 1/22/2011 1/19/1994
MORGANTOWN -1(1988)/-4(1970) 1/21/1994 1/17/2009 1/19/1994
ZANESVILLE -3(1959)/-3(1968) 1/22/2011 1/24/2011 1/19/1994
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WIND CHILL WARNING UNTIL 10 AM EST WEDNESDAY FOR MDZ001.
OH...WIND CHILL WARNING UNTIL 10 AM EST WEDNESDAY FOR OHZ039>041-
048>050-057>059-068-069.
PA...WIND CHILL WARNING UNTIL 10 AM EST WEDNESDAY FOR PAZ007>009-
013>016-020>023-029-031-073>076.
WV...WIND CHILL WARNING UNTIL 10 AM EST WEDNESDAY FOR WVZ001>004-
012-021>023-041.
&&
$$
15
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
303 PM EST MON JAN 6 2014
.SYNOPSIS...
ARCTIC AIR WILL TAKE RESIDENCE OVER THE AREA THROUGH MID-WEEK WITH
THE COLDEST TEMPERATURES IN SEVERAL YEARS BEING THE NORM.
MODERATING CONDITIONS ARE EXPECTED LATER THIS WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE ARCTIC BOUNDARY HAS CLEARED THE AREA BUT RATHER STEEP LAPSE
RATES REMAIN IN ITS WAKE. THIS HAS TWO BASIC RAMIFICATIONS TO OUR
WEATHER THROUGH THE NIGHT. FIRST...BECAUSE TEMPERATURES ARE STILL
FALLING RATHER RAPIDLY...MOISTURE IS BEING SCOURED OUT OF THE
COLUMN...WHICH HAS RESULTED IN FLURRIES DUE TO INSTABILITY IN THE
BOUNDARY LAYER. AS THE MOISTURE GETS ERADICATED OVERNIGHT...THESE
SHOULD WIND DOWN. SECOND...LOW LEVEL INSTABILITY COUPLED WITH 30+
KTS OF FLOW BELOW THE MIXING HEIGHTS SHOULD RESULT IN FAIRLY
BREEZY CONDITIONS WITH GUSTS TO AS HIGH AS 40 MPH IN THE RIDGES.
AS SUCH...AREAS OF BLOWING SNOW WILL CONTINUE TO BE
POSSIBLE...PARTICULARLY IN THE HIGHER TERRAIN. THE WINTER WEATHER
ADVISORIES WERE THUS KEPT ONLY FOR THE RIDGES AS BLOWING SNOW IS
MORE LIKELY TO BE PROBLEMATIC IN THOSE LOCATIONS.
ELSEWHERE...WINTER WEATHER ADVISORIES WERE BROUGHT DOWN DUE TO THE
END OF ACCUMULATING SNOW.
WINDS COMBINED WITH OVERNIGHT LOW TEMPERATURE EXPECTATIONS LOOK TO
BE LIFE THREATENING. GFS/NAM INITIALIZATIONS AND MODEL FIELDS
THROUGH THE NIGHT FAILED TO ADEQUATELY HANDLE THE MAGNITUDE OF THE
COLD AIR TO OUR WEST...AND WERE SUMMARILY DISMISSED FROM
CONSIDERATION FOR OUR OVERNIGHT LOWS. ECMWF AND RUC FIELDS LOOKED
A BIT BETTER...SO THE LOWS WERE CONSTRUCTED USING THE COLDER END
OF THE GUIDANCE SPECTRUM. THIS MEANS WIDESPREAD READINGS BELOW
-10F ARE EXPECTED AND RECORDS WILL LIKELY GO DOWN ACROSS THE BOARD
TONIGHT. WIND CHILLS WARNINGS WERE CONTINUED FOR -25 TO -45F
READINGS AS A RESULT OF THE TEMPERATURE/WIND COMBO. FRIES
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
DRY AND COLD CONDITIONS PREVAIL THROUGH MID-WEEK AS THE WIND CHILL
WARNING CONTINUES THROUGH WEDNESDAY MORNING. WHETHER WE MANTA IN
READINGS BELOW THE -25F CRITERIA IS DEBATABLE AFTER TUESDAY
EVENING...BUT ISSUING A WARNING FOLLOWED BY AN ADVISORY SEEMS
CONFUSING...SO ONE CONSISTENT PRODUCT WILL CONTINUE EVEN THOUGH
THE WIND CHILLS WILL NOT CONTINUE TO FALL BELOW CRITERIA.
SLOW WARM ADVECTION AND MODERATION STARTS ON WEDNESDAY. ISENTROPIC
ASCENT OVER THE COLD AIR MASS WILL BRING CHANCES OF SNOW
COINCIDING WITH WEAK SHORT WAVE PASSAGES CENTERED AROUND WEDNESDAY
EVENING AND POSSIBLY AGAIN BY LATE THURSDAY/THURSDAY NIGHT. BY
THAT JUNCTURE...TEMPERATURES SHOULD BE NEARING FREEZING...WHICH
WILL LIKELY MAKE IT FEEL DOWNRIGHT TROPICAL OUTSIDE. HOWEVER...THE
COLUMN SEEMS LIKELY TO SUPPORT MOSTLY SNOW THROUGHOUT THE SHORT
TERM PERIOD OF THE FORECAST. FRIES
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
MODELS REMAIN CONSISTENT IN BRINGING A SHORTWAVE TROUGH AT 500MB
ACROSS REGION THURSDAY NIGHT. UPPED POPS TO COINCIDE WITH THIS
FEATURE AND QUICKLY PUSH THE FOCUS OF THESE CHC POPS EAST...DRYING
BEHIND IT. NOT ALTERING THE TEMPERATURES MUCH THURS AND FRI
MORNING...SO A PRIMARILY SNOW PTYPE EVENT REMAINS THE THINKING.
SIGNIFICANT WARM UP PROGGED FOR THE WEEKEND AS RIDGING TAKES PLACE
BEHIND EXITING SHORTWAVE. 850MB TEMPS REBOUND FROM NEAR FREEZING TO
8 TO 10C SAT ON THE GFS. BUMPED UP TEMPERATURES A FEW DEGREES ACROSS
THE BOARD AS WE GO ABOVE AVERAGE FOR THIS TIME OF YEAR. A WELCOMED
CHANGE BY MOST FROM THE COLD OF THE LAST WEEK. ANOTHER QUICK MOVING
SYSTEM IS POISED TO MOVE THROUGH SAT...BUT ONLY MODEST CAA BEHIND IT
KEEPS OUR TEMPERATURES FROM FALLING OFF DRAMATICALLY. ANOTHER SYSTEM
APPROACHES FROM THE SOUTH TO START NEXT WORK WEEK...BUT CONSIDERABLE
TIMING AND STRUCTURE DIFFERENCES EXIST ON HOW TO HANDLE THE SOUTHERN
CUTOFF TRACKING ACROSS THE SOUTHEAST.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
MAIN ARCTIC FRONT APPROACHING THE RIDGES BY 18Z WITH SNOW SHOWERS
WITH AND BEHIND THE FRONT. SURFACE OBS ACROSS OHIO DEEP IN THE
COLD AIR STILL SHOWING SOME LIGHT SNOW AND BLOWING SNOW AND HAVE
KEPT A PERIOD OF TEMPO IFR MOST LOCATIONS THROUGH 21Z WITH IFR AT
TIMES ACROSS KDUJ AND KFKL INTO THE EVENING. GENERAL VFR SHOULD BE
THE RULE LATER THIS EVENING INTO TUESDAY. WINDS WILL STAY UP
THROUGH TUESDAY WITH GUSTS OVER 25KT BEFORE SUBSIDING LATER
TUESDAY.
.OUTLOOK.../MONDAY NIGHT THROUGH FRIDAY/...
THE NEXT CHANCE FOR RESTRICTIONS WILL BE LATE THURSDAY OR
FRIDAY. OTHERWISE GENERAL VFR.
&&
.CLIMATE...
VERY COLD AIR IS EXPECTED ACROSS THE REGION EARLY THIS WEEK. A
SUMMARY OF SIGNIFICANT COLD TEMPERATURE READINGS IS INCLUDED
BELOW...
CITY MON/TUE LAST DATE LAST DATE LAST DATE
RECORD(YEAR) BELOW -10 BELOW 0 HIGH BELOW 0
PITTSBURGH -5(1942)/-5(1884) 1/17/2009 1/22/2011 1/19/1994
MORGANTOWN -1(1988)/-4(1970) 1/21/1994 1/17/2009 1/19/1994
ZANESVILLE -3(1959)/-3(1968) 1/22/2011 1/24/2011 1/19/1994
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WIND CHILL WARNING UNTIL 10 AM EST WEDNESDAY FOR MDZ001.
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR MDZ001.
OH...WIND CHILL WARNING UNTIL 10 AM EST WEDNESDAY FOR OHZ039>041-
048>050-057>059-068-069.
PA...WIND CHILL WARNING UNTIL 10 AM EST WEDNESDAY FOR PAZ007>009-
013>016-020>023-029-031-073>076.
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR PAZ074-
076.
WV...WIND CHILL WARNING UNTIL 10 AM EST WEDNESDAY FOR WVZ001>004-
012-021>023-041.
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR WVZ023-
041.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
431 PM EST MON JAN 6 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 448 AM EST MON JAN 6 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP UPR TROF IN
CENTRAL NAMERICA AS ARCTIC/POLAR BRANCHES ARE IN THE PROCESS OF
PHASING...WITH THE AXIS OF LOWEST HGTS STRETCHING FM HUDSON BAY INTO
THE UPR MS RIVER VALLEY. WITHIN THE CORE OF THE COLDEST AIR...00Z
RAOBS SHOW H5/H85/H925 TEMPS AS LO AS -45C/-34C/-34C. THE PHASING OF
THE UPR BRANCHES IS SUPPORTING A DEEPENING SFC LO MOVING NNEWD INTO
SE ONTARIO. ALTHOUGH THE SYNOPTIC SCALE FORCING/PCPN ASSOCIATED WITH
THIS SFC LO ARE PASSING TO THE E OF UPR MI...SHARPENING CYC NNW FLOW
ON THE NW FLANK OF THE LO AND AREA OF DPVA/DEEP LYR QVECTOR CNVGC/
DEEPENING MID LVL MSTR AHEAD OF THE ARCTIC BRANCH SHRTWV ARE
IMPACTING MAINLY THE E HALF OF UPR MI...CAUSING AN INCRS IN LES
INTENSITY/COVERAGE IN THE FAVORED SN BELTS. AN AREA OF DEEPER MSTR
ALSO STRECHES FM NW ONTARIO S INTO MN UNDER THE AXIS OF LOWER HGTS.
TEMPS REMAIN WELL BLO NORMAL. 00Z H85 TEMPS OVER UPR MI RANGED FM
ABOUT -19C OVER THE SE TO -25C OVER THE W... SUPPORTING SFC TEMPS AS
LO AS -20F OVER THE FAR W NEAR THE WI BORDER EARLY THIS MRNG. THE
MORE NNW FLOW OFF LK SUP HAS MODERATED THE AIRMASS DOWNWIND OF THE
LK OVER THE ERN CWA...WHERE TEMPS NEAR LK SUP REMAIN CLOSE TO 10F.
THE INCRSG WINDS HAVE CAUSED WIND CHILLS TO FALL AS LO AS -35 TO
-40F OVER THE WRN CWA.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON HEADLINES RELATED TO
TEMPS/WIND CHILLS AS WELL AS LES/BLSN.
TDAY...SFC LO OVER SE ONTARIO EARLY THIS MRNG IS PROGGED TO LIFT
NEWD INTO QUEBEC AND INTENSIFY AS AXIS OF LOWEST HGTS ALF DRIFTS E
ACROSS THE UPR LKS. ALTHOUGH THE AREA OF SHARPER QVECTOR CNVGC TO
THE E OF THE UPR TROF IS PROGGED TO DRIFT TO THE E AND AWAY FM
NEWBERRY BY LATE AFTN...AREA OF DEEPER MSTR/CORE OF COLDER AIR NOTED
TO THE W IS PROGGED TO DRIFT E THRU THE UPR LKS AS WELL. THE COLDEST
H85 TEMPS ARE FCST TO PASS TO THE S THRU WI...BUT THE STEADILY
BACKING LLVL FLOW TOWARD THE W BY 00Z TUE ASSOCIATED WITH THE
DEPARTING SFC LO TO THE NE WL ALLOW FOR LESS LK SUP MODERATION OF
THE BITTERLY COLD AIRMASS. THE FOCUS OF THE HIER LES POPS WL SHIFT
AS WELL WITH THESE BACKING WINDS. ALTHOUGH ABSENCE OF DGZ WITH
BITTERLY COLD AIR WL LIMIT SN ACCUMS OVER THE W...ARRIVAL OF DEEPER
MSTR WL KEEP CONTINUOUS -SHSN GOING. SMALL SN FLAKES WL EFFICIENTLY
REDUCE VSBY AS BLSN INCREASES WITH SLOWLY INCRSG WINDS. EXPECT
SOMEWHAT HEAVIER SHSN OVER THE E WHERE LES ADVY IS IN PLACE GIVEN
SOME LINGERING DYNAMIC FORCING/WARMER AIR THAT DOES NOT HAMPER SN
GROWTH AS MUCH... BUT THE SHIFTING WINDS WL TEND TO CAUSE THE LES
BANDS TO DRIFT AS WELL. AS FOR TEMPS/WIND CHILLS...EXPECT LTL IF ANY
DIURNAL RECOVERY WITH BACKING LLVL FLOW LIMITING LK MODERATION. OVER
THE E...THIS BACKING FLOW MAY CAUSE TEMPS TO FALL. SINCE WIND SPEEDS
WL BE ON THE INCRS AS WELL...GOING WIND CHILL HEADLINES SEEM TO BE
ON TRACK.
TNGT...MODELS HINT ANOTHER SHRTWV DIVING SEWD ARND SLOWLY DEPARTING
UPR TROF AXIS WL MOVE INTO THE UPR LKS...BRINGING ANOTHER ROUND OF
DPVA/DEEP LYR QVECTOR CNVGC THAT MAINTAINS DEEPER MSTR. AS THE SFC
FLOW BACKS WITH LAND BREEZE ENHANCEMENT...LLVL CNVGC WL INCRS OVER
NRN ONTONAGON/CENTRAL HOUGHTON COUNTIES AND NEAR LK SUP E OF
MUNISING. THIS INCRSG LAND BREEZE COMPONENT WL TEND TO ADVECT LESS
MODIFIED AIR INTO THE CWA AND OFFSET SLOWLY MODERATING H85 TEMPS
WITH PASSAGE OF COLDEST CORE TO THE E. SINCE THE LLVL WINDS ARE FCST
TO INCRS AS WELL...WARNING THRESHOLD WIND CHILLS ARE LIKELY OVER
ALMOST ALL OF THE CWA.
AS FOR HEADLINES...GOING WIND CHILL WARNINGS APPEAR TO BE ON TRACK
EVEN THOUGH MORE LK MODIFIED AIR HAS MAINTAINED HIER TEMPS OVER
ABOUT THE E HALF OF THE CWA. BACKING/INCRSG WINDS LATER TDAY/TNGT
SHOULD ADVECT SUFFICIENTLY COLD AIR OVER THE ENTIRE CWA TO JUSTIFY
MAINTAINING ALL WIND CHILL WRNGS. ALTHOUGH SN AMOUNTS OVER THE W ARE
NOT LIKELY TO REACH ADVY THRESHOLDS...OPTED TO ISSUE AN LES ADVY FOR
ONTONAGON COUNTY THRU THE KEWEENAW THRU TUE TO ACCOUNT FOR THE
FREQUENT WHITEOUTS THAT WL LIKELY OCCUR WITH THE FALLING AND BLOWING
OF THE SMALL SN FLAKES. EXTENDED THE LES ADVY FOR ALGER/LUCE
COUNTIES THRU TUE AS WELL GIVEN THE POTENTIAL FOR HEAVIER SHSN
ESPCIALLY NEAR LK SUP E OF PICTURED ROCKS IN THE SHARPER LLVL CNVGC
THAT WL DVLP WITH SHARPENING LAND BREEZE CNVGC/WARMER H85 TEMPS THAT
WL NOT IMPACT SN GROWTH AS MUCH AS OVER THE W.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 431 PM EST MON JAN 6 2014
THE UPPER GREAT LAKES REGION WILL BE ON THE WEST SIDE OF THE
DEPARTING POLAR VORTEX ON TUESDAY NIGHT. THERE WILL STILL BE PLENTY
OF COLD AIR (850MB TEMPS AROUND -19C) TO PRODUCE LAKE EFFECT OVER
THE AREA...LARGELY IN THE WEST-NORTHWEST WIND SNOW BELTS. THERE
ARE A COUPLE LIMITED FACTORS TO THE SNOWFALL. FIRST...INVERSION
HEIGHTS WILL BE FALLING TO (3-5KFT) IN ASSOCIATION WITH THE 1030MB
HIGH MOVING INTO THE NORTHERN PLAINS. SECOND...FOR MUCH OF TUESDAY
NIGHT AND WEDNESDAY...WINDS LOOK TO BE CONSISTENTLY OUT OF THE
WEST-NORTHWEST...WHICH SHOULD KEEP LAKE EFFECT IN THE WIND
PARALLEL BANDS AND LIMIT HIGHER AMOUNTS DUE TO ENHANCED
CONVERGENCE. ON THE POSITIVE SIDE...THE GRADUALLY WARMING 850MB
TEMPS THROUGH WEDNESDAY (REACHING -16C OVER WESTERN LAKE SUPERIOR)
WILL PUT MORE OF THE CLOUD INTO THE DGZ AND HAVE TRENDED SNOW
RATIOS UP INTO THE LOWER 20S. THUS...WILL CONTINUE TO SHOW DEFINITE
POPS IN THE WEST-NORTHWEST WIND SNOW BELTS TUESDAY NIGHT AND
WEDNESDAY...ALTHOUGH WILL START DECREASING THEM OVER THE WEST DUE TO
INCREASED DRY AIR FROM THE HIGH THAT WILL BE LOCATED NEAR
MINNEAPOLIS AT 00Z THURSDAY. HAVE THE HIGHEST AMOUNTS ON TUESDAY
NIGHT...GENERAL 1-3IN OVER THE KEWEENAW AND EAST OF GRAND MARAIS
(HIGHEST EAST)...BEFORE THE INVERSION FALLS AND WINDS BACK THROUGH
THE DAY WEDNESDAY AND KEEPS AMOUNTS LIGHTER. WILL BE CLOSE TO WIND
CHILL ADVISORY CRITERIA ON TUESDAY NIGHT...WITH WINDS STRUGGLING TO
REACH THE 10MPH VALUES NEEDED OVER THE INLAND AREAS. WITH THE COLD
AIR AND LIGHTER WINDS...WILL STILL SEE WIND CHILL VALUES IN THE -15
TO -35 DEGREE RANGE.
THE HIGH WILL SHIFT EAST ON WEDNESDAY NIGHT AND QUICKLY MERGE WITH
A HIGH IN THE MID ATLANTIC STATES ON THURSDAY. THIS WILL LEAD TO
THE LOW LEVEL WIND FIELD BACKING MORE TO THE SOUTHWEST AND PUSH THE
LAKE EFFECT NORTH ON THURSDAY MORNING. WITH MUCH OF THE CWA UNDER
CLEAR SKIES WEDNESDAY NIGHT AND PWAT VALUES AROUND 30 PERCENT OF
NORMAL...IT SHOULD BE ANOTHER COLD NIGHT WITH LOWS IN THE SINGLE
DIGITS AND TEENS BELOW ZERO. LIGHT WINDS WILL HELP REACH THOSE
LOWS...BUT ALSO LIMIT THE WIND CHILL VALUES TO VALUES ONLY SLIGHTLY
LOWER THAN THE LOWS.
WITH THE HIGH PRESSURE RIDGE SLIDING EAST DURING THE DAY
THURSDAY...A SHORT PERIOD OF ZONAL FLOW OVER THE NORTHERN CONUS
WILL LEAD TO A WEAK SHORTWAVE AND MODERATING TEMPERATURES. AT THIS
POINT...MODELS IN DECENT AGREEMENT ON THE SHORTWAVE TRACKING
ACROSS SOUTHERN ONTARIO. WARM AIR ADVECTION AHEAD OF THIS WAVE WILL
LEAD TO INCREASING CLOUDS OVER THE AREA. THERE COULD BE SOME SNOW
SHOWERS ASSOCIATED WITH THE WARM AIR ADVECTION...BUT WITH THE TRACK
OF THE SHORTWAVE WOULD EXPECT MUCH OF IT TO MISS THE LAND AREAS OF
THE CWA. THE KEWEENAW WOULD BE THE CLOSEST TO THE WAVE AND THUS
HAVE CONTINUED SLIGHT CHANCE POPS FOR THE THURSDAY AFTERNOON AND
THURSDAY EVENING TIME PERIOD.
AREA WILL BE BETWEEN WAVES OVERNIGHT THURSDAY INTO FRIDAY
MORNING...BEFORE THE NEXT DISTURBANCE EXITS THE PACIFIC NORTHWEST
AND MOVES THROUGH THE UPPER GREAT LAKES ON FRIDAY AFTERNOON AND
SATURDAY. MODELS HAVE BEEN DIFFERING SOME ON THIS
DISTURBANCE...BUT THE 12Z GFS/ECMWF HAVE COME INTO BETTER
AGREEMENT ON THE NORTHERN STREAMS INTERACTION WITH THE SOUTHERN
JET. LATEST TRENDS HAVE THE UPPER JET STRENGTHENING AND QUICKLY
SWEEPING THE FAVORABLE LEFT FRONT REGION OF THE JET ACROSS THE AREA
FRIDAY AFTERNOON AND EVENING. WOULD LIKE TO SEE A LITTLE MORE
CONSISTENCY BEFORE TRENDING POPS UP WITH THIS WAVE...SO HAVE CHANCE
POPS OVER THE EAST HALF WHILE THIS WAVE MOVES THROUGH.
A WEAK HIGH PRESSURE RIDGE WILL LIKELY SLIDE THROUGH ON SATURDAY
NIGHT AND DIMINISH PRECIP CHANCES. 850MB TEMPS LOOK MARGINAL FOR
LES SO WILL ONLY LINGER SLIGHT CHANCES NEAR LAKE SUPERIOR. NEXT
WAVE ARRIVES ON SUNDAY AND BRING ANOTHER QUICK CHANCE OF PRECIP TO
THE AREA BEFORE ANOTHER HIGH PRESSURE RIDGE ARRRIVES FOR MONDAY.
THE TRANSITION TO MORE ZONAL FLOW ON THURSDAY AND THEN PERIODS OF
WAVES ARRIVING FROM THE PACIFIC NORTHWEST WILL LEAD TO MORE
MODERATE CONDITIONS ACROSS THE AREA FOR THE SECOND HALF OF THE WORK
WEEK AND INTO THE WEEKEND. ALTHOUGH THE TEMPERATURES WILL STRUGGLE
TO RISE INITIALLY DUE TO THE EXPECTED INVERSION AROUND 925MB...THE
PERSISTENT WEST TO SOUTHWEST FLOW WILL LEAD TO MODERATING NEAR
SURFACE TEMPS. CURRENT FORECAST HAS TEMPERATURES RISING TO NORMAL
VALUES ON FRIDAY AND THEN ABOVE NORMAL (AROUND FREEZING) FOR THE
WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1226 PM EST MON JAN 6 2014
EXTREMELY COLD AIR MASS MOVING ACROSS THE UPPER GREAT LAKES WILL
CONTINUE TO GENERATE LAKE EFFECT SNOW SHOWERS OFF LAKE SUPERIOR.
WITH WNW FLOW...KCMX/KIWD WILL BE IMPACTED BY SNOW SHOWERS...MOST
SIGNIFICANTLY AT KCMX. COMBINATION OF FALLING AND BLOWING OF THE
SMALL SNOWFLAKES AT THESE LOCATIONS WILL RESULT IN PREVAILING IFR
CONDITIONS AT KIWD AND LIFR AT KCMX. WITH KCMX MORE EXPOSED IN A WNW
WIND AND WITH BOUNDARY LAYER WINDS INCREASING...VLIFR CONDITIONS
WILL BECOME THE RULE AT KCMX THIS EVENING...IF NOT BEFORE...AND THAT
WILL CONTINUE THRU TUE MORNING. SOME IMPROVEMENT WILL BEGIN AT KIWD
TUE MORNING AND PERHAPS AT KCMX NEAR THE END OF THIS FCST PERIOD AS
WINDS DIMINISH SLOWLY AND DEEPER MOISTURE DEPARTS/INVERSIONS FALL...
RESULTING IN DIMINISHING LAKE EFFECT SNOW SHOWERS. THOUGH SOME
PERIODS OF HIGH MVFR CIGS WILL OCCUR THIS AFTN...EXPECT VFR
CONDITIONS TO PREDOMINATE AT KSAW WITH A DOWNSLOPE WNW WIND
COMPONENT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 448 AM EST MON JAN 6 2014
WITH SHARPENING PRES GRADIENT AND FLOW OF ARCTIC AIR OVER THE
RELATIVELY WARM LK WATERS...EXPECT WNW WINDS 30 KTS TO GALES TO 35
KTS THRU TONIGHT INTO TUESDAY EVENING. MAINTAINED GOING GALE
WARNINGS. THE COMBINATION OF THE BITTER COLD/SIGNIFICANT WAVE ACTION
WILL RESULT IN WIDESPREAD HEAVY FREEZING SPRAY AS WELL...SO LEFT THE
HEAVY FREEZING SPRAY WARNINGS IN EFFECT THROUGH WEDNESDAY MORNING.
OTHERWISE...HIGH PRESSURE WILL MAKE ITS WAY SOUTH OF LAKE SUPERIOR
BY MID WEEK...BUT A PERSISTANT LOW PRESSURE TROUGH NORTH OF THE LAKE
WILL KEEP WNW WINDS GUSTING TO 15 TO 25 KTS THROUGH THURSDAY.
TOWARDS THE LATTER PORTION OF THE WEEK...ANOTHER LOW PRESSURE TROUGH
WILL APPROACH THE GREAT LAKES FROM THE NORTHERN PLAINS...BACKING
WINDS TO THE SOUTHWEST AT 15 TO 25 KNOTS FOR THURSDAY AND FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL WARNING UNTIL 11 AM EST /10 AM CST/ TUESDAY FOR
MIZ001>005-009>013-084.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ085.
WIND CHILL WARNING UNTIL 11 AM EST TUESDAY FOR MIZ006-007-014-
085.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST TUESDAY FOR MIZ001>003-
006-007.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ WEDNESDAY
FOR LSZ162-243>245-248>251-263>267.
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LSZ265-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...ROLFSON
MARINE...KC/MCD
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1227 PM EST MON JAN 6 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 448 AM EST MON JAN 6 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP UPR TROF IN
CENTRAL NAMERICA AS ARCTIC/POLAR BRANCHES ARE IN THE PROCESS OF
PHASING...WITH THE AXIS OF LOWEST HGTS STRETCHING FM HUDSON BAY INTO
THE UPR MS RIVER VALLEY. WITHIN THE CORE OF THE COLDEST AIR...00Z
RAOBS SHOW H5/H85/H925 TEMPS AS LO AS -45C/-34C/-34C. THE PHASING OF
THE UPR BRANCHES IS SUPPORTING A DEEPENING SFC LO MOVING NNEWD INTO
SE ONTARIO. ALTHOUGH THE SYNOPTIC SCALE FORCING/PCPN ASSOCIATED WITH
THIS SFC LO ARE PASSING TO THE E OF UPR MI...SHARPENING CYC NNW FLOW
ON THE NW FLANK OF THE LO AND AREA OF DPVA/DEEP LYR QVECTOR CNVGC/
DEEPENING MID LVL MSTR AHEAD OF THE ARCTIC BRANCH SHRTWV ARE
IMPACTING MAINLY THE E HALF OF UPR MI...CAUSING AN INCRS IN LES
INTENSITY/COVERAGE IN THE FAVORED SN BELTS. AN AREA OF DEEPER MSTR
ALSO STRECHES FM NW ONTARIO S INTO MN UNDER THE AXIS OF LOWER HGTS.
TEMPS REMAIN WELL BLO NORMAL. 00Z H85 TEMPS OVER UPR MI RANGED FM
ABOUT -19C OVER THE SE TO -25C OVER THE W... SUPPORTING SFC TEMPS AS
LO AS -20F OVER THE FAR W NEAR THE WI BORDER EARLY THIS MRNG. THE
MORE NNW FLOW OFF LK SUP HAS MODERATED THE AIRMASS DOWNWIND OF THE
LK OVER THE ERN CWA...WHERE TEMPS NEAR LK SUP REMAIN CLOSE TO 10F.
THE INCRSG WINDS HAVE CAUSED WIND CHILLS TO FALL AS LO AS -35 TO
-40F OVER THE WRN CWA.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON HEADLINES RELATED TO
TEMPS/WIND CHILLS AS WELL AS LES/BLSN.
TDAY...SFC LO OVER SE ONTARIO EARLY THIS MRNG IS PROGGED TO LIFT
NEWD INTO QUEBEC AND INTENSIFY AS AXIS OF LOWEST HGTS ALF DRIFTS E
ACROSS THE UPR LKS. ALTHOUGH THE AREA OF SHARPER QVECTOR CNVGC TO
THE E OF THE UPR TROF IS PROGGED TO DRIFT TO THE E AND AWAY FM
NEWBERRY BY LATE AFTN...AREA OF DEEPER MSTR/CORE OF COLDER AIR NOTED
TO THE W IS PROGGED TO DRIFT E THRU THE UPR LKS AS WELL. THE COLDEST
H85 TEMPS ARE FCST TO PASS TO THE S THRU WI...BUT THE STEADILY
BACKING LLVL FLOW TOWARD THE W BY 00Z TUE ASSOCIATED WITH THE
DEPARTING SFC LO TO THE NE WL ALLOW FOR LESS LK SUP MODERATION OF
THE BITTERLY COLD AIRMASS. THE FOCUS OF THE HIER LES POPS WL SHIFT
AS WELL WITH THESE BACKING WINDS. ALTHOUGH ABSENCE OF DGZ WITH
BITTERLY COLD AIR WL LIMIT SN ACCUMS OVER THE W...ARRIVAL OF DEEPER
MSTR WL KEEP CONTINUOUS -SHSN GOING. SMALL SN FLAKES WL EFFICIENTLY
REDUCE VSBY AS BLSN INCREASES WITH SLOWLY INCRSG WINDS. EXPECT
SOMEWHAT HEAVIER SHSN OVER THE E WHERE LES ADVY IS IN PLACE GIVEN
SOME LINGERING DYNAMIC FORCING/WARMER AIR THAT DOES NOT HAMPER SN
GROWTH AS MUCH... BUT THE SHIFTING WINDS WL TEND TO CAUSE THE LES
BANDS TO DRIFT AS WELL. AS FOR TEMPS/WIND CHILLS...EXPECT LTL IF ANY
DIURNAL RECOVERY WITH BACKING LLVL FLOW LIMITING LK MODERATION. OVER
THE E...THIS BACKING FLOW MAY CAUSE TEMPS TO FALL. SINCE WIND SPEEDS
WL BE ON THE INCRS AS WELL...GOING WIND CHILL HEADLINES SEEM TO BE
ON TRACK.
TNGT...MODELS HINT ANOTHER SHRTWV DIVING SEWD ARND SLOWLY DEPARTING
UPR TROF AXIS WL MOVE INTO THE UPR LKS...BRINGING ANOTHER ROUND OF
DPVA/DEEP LYR QVECTOR CNVGC THAT MAINTAINS DEEPER MSTR. AS THE SFC
FLOW BACKS WITH LAND BREEZE ENHANCEMENT...LLVL CNVGC WL INCRS OVER
NRN ONTONAGON/CENTRAL HOUGHTON COUNTIES AND NEAR LK SUP E OF
MUNISING. THIS INCRSG LAND BREEZE COMPONENT WL TEND TO ADVECT LESS
MODIFIED AIR INTO THE CWA AND OFFSET SLOWLY MODERATING H85 TEMPS
WITH PASSAGE OF COLDEST CORE TO THE E. SINCE THE LLVL WINDS ARE FCST
TO INCRS AS WELL...WARNING THRESHOLD WIND CHILLS ARE LIKELY OVER
ALMOST ALL OF THE CWA.
AS FOR HEADLINES...GOING WIND CHILL WARNINGS APPEAR TO BE ON TRACK
EVEN THOUGH MORE LK MODIFIED AIR HAS MAINTAINED HIER TEMPS OVER
ABOUT THE E HALF OF THE CWA. BACKING/INCRSG WINDS LATER TDAY/TNGT
SHOULD ADVECT SUFFICIENTLY COLD AIR OVER THE ENTIRE CWA TO JUSTIFY
MAINTAINING ALL WIND CHILL WRNGS. ALTHOUGH SN AMOUNTS OVER THE W ARE
NOT LIKELY TO REACH ADVY THRESHOLDS...OPTED TO ISSUE AN LES ADVY FOR
ONTONAGON COUNTY THRU THE KEWEENAW THRU TUE TO ACCOUNT FOR THE
FREQUENT WHITEOUTS THAT WL LIKELY OCCUR WITH THE FALLING AND BLOWING
OF THE SMALL SN FLAKES. EXTENDED THE LES ADVY FOR ALGER/LUCE
COUNTIES THRU TUE AS WELL GIVEN THE POTENTIAL FOR HEAVIER SHSN
ESPCIALLY NEAR LK SUP E OF PICTURED ROCKS IN THE SHARPER LLVL CNVGC
THAT WL DVLP WITH SHARPENING LAND BREEZE CNVGC/WARMER H85 TEMPS THAT
WL NOT IMPACT SN GROWTH AS MUCH AS OVER THE W.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 448 AM EST MON JAN 6 2014
THE 500MB LOW RESPONSIBLE FOR THE ACTIVE WEATHER ACROSS THE GREAT
LAKES THIS WEEK WILL BE OVER QUEBEC TUESDAY MORNING. THIS LOW WILL
LINGER A TROUGH OVER THE GREAT LAKES THROUGH THE DAY TUESDAY AND
WEDNESDAY. AT THE SURFACE...HIGH PRESSURE WILL SINK TOWARDS THE GULF
OF MEXICO. THE SURFACE LOW OVER THE LOWER LAKES MONDAY NIGHT WILL
MAKE ITS WAY INTO QUEBEC BY TUESDAY...KEEPING A WEAK TROUGH OVER
EASTERN LAKE SUPERIOR THROUGH WEDNESDAY. OVERALL...UPPER MI WILL
REMAIN IN WEST-NORTHWEST FLOW THROUGH THE FIRST PORTION OF THE LONG
TERM...CAUGHT BETWEEN THE HIGH IN THE SOUTHEAST AND THE LOW IN
QUEBEC. THOUGH WINDS WILL BE GUSTY THROUGH MOST OF TUESDAY...THEY
WILL GRADUALLY LESSEN AS THE HIGH MAKES ITS WAY INTO THE CWA TUESDAY
NIGHT INTO WEDNESDAY. WITH THE COLD ARCTIC AIR IN PLACE...LES WILL
CONTINUE IN WNW-WIND FAVORED SNOWBELTS. WITH DWINDLING
MOISTURE/EXTREME COLD...SNOW RATIOS WILL BE UNSUPPORTIVE OF
SIGNIFICANT ACCUMULATIONS ACROSS THE AREA FOR THIS TIME PERIOD. FOR
NOW HAVE 2 TO 4 INCHES OF ACCUMULATION FROM TUESDAY MORNING INTO
WEDNESDAY MORNING FOR EASTERN ALGER/LUCE COUNTY...AND 1 TO 2 INCHES
ACROSS ONTONAGON...HOUGHTON...AND KEWEENAW COUNTY.
THE MAIN CONCERN WILL BE LOWERED VISIBILITY DUE TO THE SMALL FLAKE
SIZE AND BLOWING SNOW/FROM GUSTY WNW WINDS/ NEAR THE LAKESHORE ALL
DAY TUESDAY...AND WIND CHILLS THROUGH LATE TUESDAY MORNING. FOR
HEADLINES...HAVE LES ADVISORY THROUGH TUESDAY IN WNW WIND FAVORED
SNOWBELTS...MAINLY ONTONAGON....NORTHERN
HOUGHTON...KEWEENAW...ALGER...AND LUCE COUNTIES TO ACCOUNT FOR THE
SNOW/BLOWING SNOW/WIND CHILL. ELSEWHERE...SOLELY THE WIND CHILL
WARNING REMAINS IN EFFECT. WIND CHILLS TUESDAY MORNING WILL RANGE
FROM -50F TO -25F ACROSS THE FORECAST AREA...WITH THE COLDEST
READINGS ACROSS THE INTERIOR WEST.
THE HIGH WILL GRADUALLY CROSS THE GREAT LAKES LATE WEDNESDAY INTO
THURSDAY...AND THEN REACH THE NEW ENGLAND STATES BY THURSDAY NIGHT.
AS THE HIGH MOVES OUT...WINDS BACK TO THE SOUTHWEST. THIS BRINGS
EXTREMELY DRY AIR INTO MUCH OF THE CWA BY EARLY WEDNESDAY
EVENING...STARTING A DISSIPATING TREND TO THE LES THROUGH THURSDAY
MORNING. ADDITIONALLY...WITH WINDS BACKING SOUTHWEST...MOST OF THE
REMAINING LES WILL MOVE OFFSHORE INTO LAKE SUPERIOR. THE BEST CHANCE
FOR SNOW SHOWERS ON THURSDAY IS OVER THE KEWEENAW.
MODELS BEGIN TO DISAGREE LATE THURSDAY INTO FRIDAY ON HOW TO HANDLE
AN UPPER LEVEL TROUGH MOVING INTO THE NORTHERN PLAINS...BOTH WITH
THE TIME AND STRENGTH OF THE OVERALL FEATURE. THE ECMWF BRINGS A
MORE SHALLOW TROUGH ACROSS THE GREAT LAKES FRIDAY NIGHT/SAT
MORNING...WHEREAS THE GFS BRINGS A DEEPER TROUGH THROUGH ON SATURDAY
EVENING. BY THIS TIME...THE ECMWF HAS ZONAL FLOW ALOFT FOR UPPER MI.
THE GEM SEEMS TO BE THE MIDDLE OF THE ROAD...BRINGING THE TROUGH
THROUGH THE GREAT LAKES SATURDAY AFTERNOON...WITH A STRENGTH SIMILAR
TO THAT OF THE ECMWF. BY SUNDAY AND MONDAY...THESE DIFFERENCES ARE
EXACERBATED...ESPECIALLY AT THE SURFACE. THE ECMWF KEEPS A WEAK SURFACE
TROUGH OVER THE GREAT LAKES THROUGH SUNDAY AFTERNOON...AND THEN
BRINGS A SURFACE HIGH ACROSS THE NORTHERN PLAINS INTO THE GREAT LAKES
FOR MONDAY. THE GFS BRINGS A CLOSED LOW PRESSURE SYSTEM ACROSS
MANITOBA AND INTO JAMES BAY...WHICH KEEPS A TROUGH OVER UPPER MI.
WILL KEEP THE CONSENSUS POPS FOR NOW GIVEN SUCH DRAMATIC DIFFERENCES.
ON A POSITIVE NOTE...MODELS TRENDING UPWARD WITH TEMPERATURES THROUGH
THE PERIOD...WITH HIGHS IN THE UPPER 20S AND LOW 30S BY NEXT WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1226 PM EST MON JAN 6 2014
EXTREMELY COLD AIR MASS MOVING ACROSS THE UPPER GREAT LAKES WILL
CONTINUE TO GENERATE LAKE EFFECT SNOW SHOWERS OFF LAKE SUPERIOR.
WITH WNW FLOW...KCMX/KIWD WILL BE IMPACTED BY SNOW SHOWERS...MOST
SIGNIFICANTLY AT KCMX. COMBINATION OF FALLING AND BLOWING OF THE
SMALL SNOWFLAKES AT THESE LOCATIONS WILL RESULT IN PREVAILING IFR
CONDITIONS AT KIWD AND LIFR AT KCMX. WITH KCMX MORE EXPOSED IN A WNW
WIND AND WITH BOUNDARY LAYER WINDS INCREASING...VLIFR CONDITIONS
WILL BECOME THE RULE AT KCMX THIS EVENING...IF NOT BEFORE...AND THAT
WILL CONTINUE THRU TUE MORNING. SOME IMPROVEMENT WILL BEGIN AT KIWD
TUE MORNING AND PERHAPS AT KCMX NEAR THE END OF THIS FCST PERIOD AS
WINDS DIMINISH SLOWLY AND DEEPER MOISTURE DEPARTS/INVERSIONS FALL...
RESULTING IN DIMINISHING LAKE EFFECT SNOW SHOWERS. THOUGH SOME
PERIODS OF HIGH MVFR CIGS WILL OCCUR THIS AFTN...EXPECT VFR
CONDITIONS TO PREDOMINATE AT KSAW WITH A DOWNSLOPE WNW WIND
COMPONENT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 448 AM EST MON JAN 6 2014
WITH SHARPENING PRES GRADIENT AND FLOW OF ARCTIC AIR OVER THE
RELATIVELY WARM LK WATERS...EXPECT WNW WINDS 30 KTS TO GALES TO 35
KTS THRU TONIGHT INTO TUESDAY EVENING. MAINTAINED GOING GALE
WARNINGS. THE COMBINATION OF THE BITTER COLD/SIGNIFICANT WAVE ACTION
WILL RESULT IN WIDESPREAD HEAVY FREEZING SPRAY AS WELL...SO LEFT THE
HEAVY FREEZING SPRAY WARNINGS IN EFFECT THROUGH WEDNESDAY MORNING.
OTHERWISE...HIGH PRESSURE WILL MAKE ITS WAY SOUTH OF LAKE SUPERIOR
BY MID WEEK...BUT A PERSISTANT LOW PRESSURE TROUGH NORTH OF THE LAKE
WILL KEEP WNW WINDS GUSTING TO 15 TO 25 KTS THROUGH THURSDAY.
TOWARDS THE LATTER PORTION OF THE WEEK...ANOTHER LOW PRESSURE TROUGH
WILL APPROACH THE GREAT LAKES FROM THE NORTHERN PLAINS...BACKING
WINDS TO THE SOUTHWEST AT 15 TO 25 KNOTS FOR THURSDAY AND FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL WARNING UNTIL 11 AM EST /10 AM CST/ TUESDAY FOR
MIZ001>005-009>013-084.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ014-
085.
WIND CHILL WARNING FROM 7 PM THIS EVENING TO 11 AM EST TUESDAY
FOR MIZ006-007-014-085.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST TUESDAY FOR MIZ001>003-
006-007.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ WEDNESDAY
FOR LSZ162-243>245-248>251-263>267.
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LSZ265-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...MCD
AVIATION...ROLFSON
MARINE...KC/MCD
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1219 PM CST MON JAN 6 2014
.UPDATE...
HAVE CONVERTED WIND CHILL WARNINGS INTO WIND CHILL ADVISORIES FOR
MOST OF THE CWA BEGINNING AT NOON. WIND CHILLS HAVE BEEN SOLIDLY
IN THE 25 BELOW RANGE BY LATE MORNING...EXPECT FOR AREAS NORTHEAST
OF THE OMAHA METRO. TEMPERATURES WERE APPROACHING OR EXCEEDING ZERO
IN OUR SOUTHWEST ALREADY...AND EXPECT THOSE AREAS TO AT LEAST
REACH THE MIDDLE SINGLE DIGITS WITH WIND CHILLS 10 TO 15 BELOW.
ALSO EXPECT WINDS TO REALLY DIE DOWN THIS EVENING AS PER
CONCURRENCE OF MESOSCALE MODELS. THUS WIND CHILLS WILL BE
IMPROVING MARKEDLY THEN DESPITE THE POTENTIAL FOR A QUICK DROP IN
AIR TEMPERATURES DURING A LIGHT WIND/CLEAR SKY EVENING. INCREASING
MID/HIGH CLOUDS IN MID LEVEL WARM ADVECTION REGIME ALONG WITH
WINDS BECOMING MORE SOUTHERLY WITH TIME OVERNIGHT SUGGESTS AN
EVENING LOW WITH RISING TEMPERATURES AFTER MIDNIGHT. THUS HAVE
TAPERED WIND CHILL ADVISORY EXPIRATIONS FROM SOUTHWEST TO
NORTHEAST WITH TIME...AND ALL AREAS VOID OF HEADLINES BY MIDNIGHT.
DERGAN
&&
.AVIATION...18Z TAFS FOR KOFK...KLNK AND KOMA.
PATCHY STRATO CU COULD GO BROKEN AROUND FL025 FOR A TIME THIS
AFTERNOON BEFORE DISSIPATING BY SUNSET. OTHERWISE VFR CONDITIONS
ARE EXPECTED AT ALL TAF SITES. MID LEVEL SCATTERED TO BROKEN
CLOUDS WILL LIKELY OVERSPREAD THE AREA AFTER MIDNIGHT. NORTHWEST
WINDS 15 TO 25KT SHOULD DIE DOWN TO LESS THAN 10KT SHORTLY AFTER
00Z THEN BECOME SOUTHERLY BEFORE 12Z.
DERGAN
&&
.PREV DISCUSSION... /ISSUED 258 AM CST MON JAN 6 2014/
DISCUSSION...
CENTER OF ARCTIC HIGH PRESSURE HAD SHIFTED SOUTH OF THE AREA AT
08Z OVER OKLAHOMA WITH SURFACE GRADIENT WEAKENING OVER NEBRASKA.
AS A RESULT SURFACE WINDS BECOMING MORE VARIABLE EARLY THIS
MORNING WITH REGARD TO SPEED. SEVERAL SITES REPORTING LESS THAN
10 KTS AT 08Z. WIND CHILL VALUES HOWEVER GENERALLY RANGE FROM -25
TO -35 ACROSS THE FORECAST AREA. RAP INDICATES SURFACE GRADIENT
MAY INCREASE AGAIN DURING THE MORNING WITH WINDS PICKING UP TO
BETWEEN 10 AND 20 KTS.
ADJUSTMENTS TO CURRENT HEADLINES MAY BE NEEDED BEFORE EXPIRATION
BUT WILL PASS THIS ON TO THE DAY SHIFT TO BETTER DELINEATE TRENDS
AND AREAL IMPACT.
TEMPERATURES ARE STILL EXPECTED TO REMAIN BELOW ZERO TODAY FROM
NORTHEAST NEBRASKA INTO SOUTHWEST IOWA WITH ONLY LOW SINGLE
DIGITS TO THE WEST OF THAT AREA. SUBZERO TEMPERATURES LIKELY TO
REMAIN ACROSS MOST OF THE AREA YET TONIGHT BUT RELATIVELY WARMER
TEMPERATURES RETURN ON TUESDAY IN ADVANCE OF A WEAK CLIPPER COMING
OUT OF THE NORTHERN ROCKIES. ANOTHER PUSH OF COLD AIR MOVES INTO
THE REGION BEHIND THIS SYSTEM TUESDAY NIGHT INTO WEDNESDAY BUT NOT
AS EXTREME AS CURRENT AIRMASS OVER THE REGION.
MODELS INDICATE LESS AMPLIFIED FLOW BY WEDNESDAY WITH SPLIT FLOW
DEVELOPING IN THE EXTENDED PORTION OF THE FORECAST. THIS IS
EXPECTED TO RESULT IN TEMPERATURES CLOSER TO NORMAL OR SLIGHTLY
ABOVE FOR EARLY JANUARY. ALTHOUGH NO MAJOR WINTER STORM SYSTEM IS
INDICATED...SHORT WAVES MOVING THROUGH THE FLOW DURING THIS TIME
MAY TRIGGER PERIODS OF LIGHT SNOW FOR PARTS OF THE AREA BUT TIMING
AND STRENGTH UNCERTAIN FOR LIMITED CONFIDENCE IN ANY MENTION
BEYOND SLIGHT POPS.
FOBERT
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WIND CHILL ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR NEZ011-012-
015-017-018-032>034-045.
WIND CHILL ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR NEZ065-066-
068-078-088>093.
WIND CHILL ADVISORY UNTIL 6 PM CST THIS EVENING FOR NEZ016-030-
031-042>044-050>053-067.
IA...WIND CHILL ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR IAZ055-069-
079-080-091.
WIND CHILL WARNING UNTIL 3 PM CST THIS AFTERNOON FOR IAZ043-056.
WIND CHILL ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR IAZ043-056.
WIND CHILL ADVISORY UNTIL 6 PM CST THIS EVENING FOR IAZ090.
&&
$$
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
428 PM CST MON JAN 6 2014
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND TUESDAY
ISSUED AT 231 PM CST MON JAN 6 2014
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW ARCTIC HIGH
PRESSURE STRETCHING FROM SOUTHERN SASKATCHEWAN TO THE GULF COAST OF
TEXAS EARLY THIS AFTERNOON. THE POLAR VORTEX IS SHIFTING EAST INTO
MICHIGAN THOUGH THE CORE OF THE EXTREMELY COLD AIR IS CURRENTLY
OVERHEAD. TEMPERATURES HAVE NOT WARMED TOO MUCH SO FAR TODAY...WITH
READINGS HOLDING STEADY FROM THE LOWER TEENS BELOW ZERO ALONG THE
LAKE MICHIGAN SHORELINE TO THE LOWER 20S BELOW ZERO OVER CENTRAL
WISCONSIN. WIND CHILLS REMAIN IN THE 35 TO 45 DEGREES BELOW ZERO
RANGE. AREAS OF THIN CLOUD COVER CONTINUE TO STREAM SOUTHEAST ON
THE BACKSIDE OF THE POLAR VORTEX...WITH A FEW FLURRIES BEING
REPORTED ON AREA OBSERVATION SITES. AS THE ARCTIC AIR
MODIFIES...TEMPS AND WIND CHILLS REMAIN THE MAIN FORECAST
CONCERNS...FOLLOWED BY CLOUDS/FLURRY CHANCES.
TONIGHT...ARCTIC HIGH PRESSURE WILL SLIDE TO THE GULF COAST...BUT
THE SURFACE RIDGE AXIS WILL HANG BACK ACROSS THE NORTHERN
MISSISSIPPI TO CENTRAL CANADA. THOUGH TEMPERATURES WILL BE
MODIFYING ALOFT...BRISK WEST WINDS WILL CONTINUE TO FUNNEL IN THE
EXTREME COLD FROM THE NORTHERN PLAINS. DO NOT HAVE A GOOD HANDLE ON
CLOUD COVER TONIGHT...BUT WITH THIN CLOUDS DROPPING SOUTH OVER
SOUTHERN CANADA AND MINNESOTA...FIGURE THE REGION WILL HAVE PARTLY
CLOUDY CONDITIONS THROUGH THE EVENING BEFORE A SLIGHT BACKING OF THE
WINDS PUSHES IN DRIER AIR IN AFTER MIDNIGHT. WITH THE SUSTAINED
WINDS AND A MODIFYING AIRMASS...TEMPS WILL BE A DEGREE OR TWO WARMER
OVER WESTERN SECTIONS OF THE FORECAST AREA...THOUGH WILL LIKELY BE A
FEW DEGREES COLDER OVER EASTERN SECTIONS. BUT WITH WINDS REMAINING
IN THE 10-15KT RANGE...WIND CHILLS WILL REMAIN IN THE 40 TO 50
DEGREE BELOW ZERO RANGE. THUS NO CHANGE TO HEADLINES.
TUESDAY...THE SURFACE RIDGE AXIS WILL SHIFT SLIGHTLY INTO WESTERN
WISCONSIN IN THE AFTERNOON WITH ONLY MID AND HIGH CLOUDS MOVING
OVERHEAD. THE WEST WINDS WILL NOT BE AS STRONG OR GUSTY AS
TODAY...AND COMBINED WITH FURTHER MODIFYING OF THE ARCTIC
AIRMASS...SHOULD SEE TEMPS ABOUT 10 DEGREES WARMER THAN TODAY
ACCORDING TO THE LEADING GUIDANCE. THE EXTREMELY COLD WIND CHILLS
ARE EXPECTED TO RISE TO BETWEEN 20 TO 30 DEGREES BELOW ZERO BY EARLY
AFTERNOON.
.LONG TERM...TUESDAY NIGHT THROUGH MONDAY
ISSUED AT 231 PM CST MON JAN 6 2014
GRADUALLY IMPROVING TEMPERATURES THIS WEEK WILL BE THE PRIMARY
ISSUE FOLLOWED WITH SOME RESOLUTION WITH A FEW PRECIP CHANCES IN
THE NEAR ZONAL FLOW LATE THIS WEEK AND THROUGH THIS WEEKEND.
FOR STARTERS...ANTICIPATE THE ARCTIC AIR MASS WILL TAKE ITS TIME
TO DEPART THIS WEEK EVEN THOUGH H850 TEMPERATURES INCREASE. VERY
COLD DRY AIR MASS WILL BE RECYCLED BACK NORTH WITH THE RETURN FLOW
THROUGH THURSDAY. ANTICIPATED CLEAR SKIES AND LIGHT WINDS UNDER A
COLD HIGH PRESSURE SYSTEM WILL PROVIDE LARGE DIURNAL CHANGES WITH
SUB ZERO LOW TEMPERATURES CONTINUING INTO THURSDAY MORNING OVER
MOST LOCATIONS.
RETURN SOUTH TO SOUTHWEST FLOW BEGINS LATER THURSDAY SO TEMPS
WILL START TO ASCEND QUICKER WITH TEMPERATURES POSSIBLY REACHING
THE FREEZING MARK THIS WEEKEND OVER PARTS OF THE AREA. CLOUDS MAY
BE ON THE INCREASE OVER SOUTHERN WISCONSIN THROUGH THURSDAY WITH
THE PASSAGE OF A SOUTHERN STREAM SYSTEM TO THE SOUTH...BUT EXPECT THE
AREA TO REMAIN DRY WITH THE SURFACE HIGH STILL SETTLED OVER THE
AREA.
MODEL TIMING OF VARIOUS SHORT WAVES IN THE NEAR ZONAL FLOW POINTING
TO A FRIDAY INTO FRIDAY NIGHT TIME FRAME. A WEAK RIDGE SETTLES
OVER SATURDAY INTO SUNDAY BEFORE POSSIBLY ANOTHER WEAK SYSTEM
PASSES OVER LATER SUNDAY. AGAIN MODEL TIME IN QUESTION DUE TO
TIMING OF THESE SHORT WAVES IN THE ZONAL FLOW AND LIKELY WILL NEED
FURTHER ADJUSTMENTS.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 427 PM CST MON JAN 6 2014
VFR CONDITIONS EXPECTED AS BITTERLY COLD ARCTIC AIR DOMINATES THE
AREA. LLWS WL DEVELOP TNGT AS THE AIR ALOFT STARTS TO WARM...AND
INVERSION STRENGTHENS/LOWERS.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
WIND CHILL WARNING UNTIL NOON CST TUESDAY FOR WIZ005-010>013-
018>022-030-031-035>040-045-048>050-073-074.
&&
$$
SHORT TERM.....MPC
LONG TERM......TDH
AVIATION.......SKOWRONSKI
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
243 PM CST MON JAN 6 2014
...LIFE-THREATENING WIND CHILLS CONTINUE INTO TUESDAY MORNING...
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 243 PM CST MON JAN 6 2014
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING OVER THE WESTERN U.S. INTO BRITISH COLUMBIA AND AN
ANOMALOUSLY DEEP TROUGH ENCOMPASSING MUCH OF THE EASTERN U.S..
WITHIN THIS DEEP TROUGH...THE POLAR VORTEX STRETCHED FROM NORTHERN
ONTARIO INTO LOWER MI. THE COLDEST AIR ASSOCIATED WITH THE VORTEX
HAS BEEN ON ITS BACK SIDE...NOTED BY 925MB TEMPS AT 12Z OF -34C AT
MPX AND -35C AT INL...OR 3-3.5 STANDARD DEVIATIONS BELOW NORMAL.
THIS ARCTIC AIR HAS MODIFIED SOMEWHAT THROUGH DAYTIME HEATING...BUT
925MB TEMPS PER RAP ANALYSIS ARE STILL NEAR -30C. SURFACE
TEMPERATURES HAVE MANAGED TO CLIMB INTO THE TEENS BELOW ZERO.
HOWEVER...A PERSISTENT 10 TO 20 MPH WIND WITH GUSTS TO 30 MPH HAVE
KEPT WIND CHILLS DOWN TO 35 TO 45 BELOW ZERO. THESE WINDS ARE A
RESULT OF A TIGHT PRESSURE GRADIENT BETWEEN A SURFACE RIDGE OVER
THE DAKOTAS AND A DEEP LOW OVER CENTRAL QUEBEC.
THE POLAR VORTEX IS PROGGED TO GRADUALLY LOSE ITS GRIP ACROSS THE
FORECAST AREA AND GREAT LAKES REGION...LIFTING INTO NORTHERN QUEBEC
BY 00Z WEDNESDAY. THIS WILL ALLOW WARMER AIR TO ENTER THE
REGION. ONE CAVEAT TO THE WARMER AIR IS A SHORTWAVE OVER THE
NORTHWEST TERRITORIES WHICH MODELS SHOW DROPPING DOWN THE BACK SIDE
OF THE VORTEX...COMING INTO NORTHERN WI AT 00Z WEDNESDAY. THIS
SHORTWAVE WILL SLOW SOME OF THE WARM UP.
REGARDING TEMPERATURES...925MB READINGS ARE PROGGED TO CLIMB THROUGH
THE NEXT 24 HOURS...REACHING -24 TO -28C BY 12Z TUE AND TO -18 TO -
22C BY 00Z WED. DESPITE THE WARMING ABOVE THE SURFACE...TEMPERATURES
SHOULD STILL COOL DOWN CLOSE TO READINGS SEEN LAST NIGHT BECAUSE OF
WINDS WHICH ARE GOING TO BE LIGHTER. HOWEVER...A BREEZE WILL PERSIST
SINCE THE SURFACE RIDGE IS STILL OFF TO OUR WEST...WHICH MEANS WIND
CHILL VALUES ARE LIKELY TO STAY BETWEEN 35 AND 55 BELOW ZERO. WINDS
DO MANAGE TO BACK MORE WEST TO POSSIBLY EVEN SOUTHWEST ON TUESDAY...
AHEAD OF A COLD FRONT DROPPING THROUGH MN THAT IS ACCOMPANYING THE
NORTHWEST TERRITORIES SHORTWAVE. THIS BACKING OF WINDS PLUS WARMER
925MB VALUES AND SOME SUN SHOULD HELP BOOST HIGHS TOWARDS THE SINGLE
DIGITS ABOVE ZERO...AT LEAST SOUTHWEST OF I-94. NORTH OF I-94...WIND
CHILL ISSUES ARE GOING TO CONTINUE THROUGH THE AFTERNOON AND AN
ADVISORY WILL BE NEEDED AFTER THE WARNING EXPIRES.
SKY COVER REMAINS A TRICKY FORECAST IN THIS ARCTIC AIRMASS.
ANTICIPATING A PERIOD OF POSSIBLY CLEAR SKIES THIS EVENING ONCE ANY
DIURNAL STRATOCUMULUS DISSIPATES WITH LOSS OF DAYTIME HEATING.
HOWEVER...LOW STRATUS CURRENTLY IN SOUTHERN MANITOBA AND NORTHWEST
MN LOOKS TO MAKE A RUN AT LOCATIONS NORTH OF I-94 LATE THIS EVENING
INTO THE OVERNIGHT HOURS. MID/HIGH CLOUDS SHOULD THEN INCREASE
OVERNIGHT THROUGH TUESDAY...WITH EVEN SOME LOWER STRATUS ACROSS
SOUTHERN PORTIONS OF THE AREA...AS ISENTROPIC LIFT PICKS UP AHEAD
OF THE COLD FRONT AND SHORTWAVE. SOME FLURRIES COULD OCCUR FROM
THE CLOUDS AS WELL ACROSS THE SOUTHWESTERN HALF OF THE AREA ON
TUESDAY AS CLOUD HEIGHTS THERE FALL.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 243 PM CST MON JAN 6 2014
MODELS REMAIN IN AGREEMENT SHOWING THE PATTERN GREATLY DEAMPLIFYING
ACROSS THE U.S....BECOMING ZONAL BY THURSDAY MORNING. THIS WILL
SHIFT THE TEMPERATURE FLOW FROM THE ARCTIC TO THE PACIFIC. WE DO
HAVE TO WAIT JUST A LITTLE BIT LONGER AS THAT SHORTWAVE DROPPING
INTO NORTHERN WISCONSIN BRINGS A BRIEF REINFORCING SHOT OF COLD AIR
TUESDAY NIGHT. THIS SHOT OF COLD AIR WILL BE NOTICED THE MOST IN
NORTHERN WI WHERE WIND CHILLS LOOK TO STAY DOWN BETWEEN 20 AND 35
BELOW ZERO. A SURFACE HIGH PRESSURE AREA IS PROGGED TO DRIFT
ACROSS THE FORECAST AREA LATE WEDNESDAY INTO WEDNESDAY NIGHT. THIS
HIGH SHOULD HELP TO CALM THE WINDS DOWN...WHICH DOES BRING A
CONCERN FOR LOW TEMPERATURES WEDNESDAY NIGHT...ESPECIALLY OVER
WISCONSIN. AIRMASS REMAINS QUITE DRY WITH PRECIPITABLE WATER BELOW
0.1 INCHES...SO TEMPERATURES COULD REALLY TANK IN THE TYPICALLY
COLD SPOTS. SOUTHERLY FLOW ON THE BACK SIDE OF THIS HIGH PRESSURE
AREA KICKS WARM ADVECTION INTO HIGH GEAR ON THURSDAY. 925MB TEMPS
CLIMB TO -6 TO -10C. ALTHOUGH THERE MAY BE QUITE A FEW CLOUDS
AROUND...THESE SOUTHERLY WINDS SHOULD HELP PROPEL TEMPERATURES
GENERALLY INTO THE MID TEENS TO AROUND 20...ABOUT 30 DEGREES
WARMER THAN TODAY. NOTE...THERE COULD BE SOME WIND CHILL ISSUES
THURSDAY MORNING AS THE SOUTH WINDS INCREASE. THERE WERE SOME
HINTS OF THE 06.15Z SREF OF SOME POSSIBLE PRECIPITATION WITH THIS
WARM ADVECTION...BUT KEPT THESE OUT WITH NO OTHER DETERMINISTIC
MODEL GUIDANCE SHOWING IT.
HIGHLIGHTS FOR FRIDAY INTO MONDAY...
1. GOOD MODEL AGREEMENT EXISTS THAT A FAIRLY SIGNIFICANT SHORTWAVE
TROUGH WILL MOVE FROM THE PACIFIC NORTHWEST ON THU...TO THE NORTHERN
PLAINS ON FRI AND GREAT LAKES ON SAT. A PLUME OF HIGHER PRECIPITABLE
WATER ON THE ORDER OF A 0.5-0.7 INCHES COMES INTO THE REGION AHEAD
OF THE TROUGH ON FRIDAY. COMBINING THIS MOISTURE WITH THE DPVA AND
ISENTROPIC LOOKS TO YIELD SOME PRECIPITATION. HAVE RAISED POPS ABOUT
5-10 PERCENT...BUT IF THE TRENDS IN THE 06.12Z GFS/ECMWF CONTINUE
THESE CHANCES NEED TO BE RAISED FURTHER. NOTE THAT THE 06.12Z
CANADIAN HOLDS PRECIPITATION OFF TIL FRIDAY NIGHT...WHICH IS PARTLY
THE CAUSE TOO OF THE SMALLER CHANCE INCREASE. THE TYPE IS
SOMEWHAT OF AN ISSUE TOO...DUE TO A LOSS OF ICE IN THE CLOUD AND
WARM LAYER INITIALLY FRIDAY MORNING. IT APPEARS ONCE THINGS
SATURATE...EVAPORATIVE COOLING KNOCKS DOWN ANY WARM LAYER AND CLOUDS
ARE SEEDED WITH ICE. THIS SHOULD OCCUR BY EARLY AFTERNOON.
PRECIPITATION SHOULD END WEST TO EAST FRIDAY NIGHT AS THE SYSTEM
PULLS AWAY. ANY LOSS OF ICE IN THE CLOUDS FRIDAY NIGHT SHOULD OCCUR
AFTER THE PRECIP EXITS.
2. A SERIES OF TWO SHORTWAVE TROUGHS TRACKING ACROSS THE REGION
SUNDAY THROUGH MONDAY. PREVIOUSLY ECMWF RUNS WERE SUGGESTING THAT
THESE TROUGHS WERE GOING TO HOLD BACK OVER THE WESTERN U.S.. NOW
THEY ARE MORE PROGRESSIVE...LIKE THE 05.12Z GFS RUN. THIS MEANS A
BIT LESS CONFIDENCE IN PRECIPITATION AS MOISTURE RETURN BEHIND THE
SATURDAY SYSTEM IS SLOWER TO COME BACK. THEREFORE...CHANCES WERE
LOWERED. IT IS ENTIRELY POSSIBLE SUNDAY THROUGH MONDAY ENDS UP
MAINLY DRY.
3. ABOVE NORMAL TEMPERATURES. BOTH THE FRIDAY AND SUNDAY SHORTWAVE
TROUGHS HELP TO PULL EVEN WARMER AIR INTO THE REGION. 925MB TEMPS
GET UP CLOSE TO 0C ON FRIDAY...COOL SLIGHTLY TO -2 TO -6C ON
SATURDAY...BACK UP TO 0-3C ON SUNDAY AND DOWN TO -2 TO -6C ON
MONDAY. EACH OF THESE DAYS WE SHOULD BE ABLE TO GET HIGHS INTO THE
UPPER 20S TO LOW 30S...AND SUNDAY THERE ARE SIGNS WE COULD TRY TO
PUSH 40. RAISED HIGHS A LITTLE ON SUNDAY AS A RESULT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1141 AM CST MON JAN 6 2014
A WEAK SHORT WAVE TROUGH WILL PRODUCE A SCATTERED TO BROKEN DECK
OF MVFR CLOUDS THIS AFTERNOON. IN ADDITION...WINDS ARE STRONG
ENOUGH THIS AFTERNOON TO KEEP SOME BLOWING SNOW GOING ON IN
SOUTHEAST MN...REDUCING VISIBILITIES TO MVFR/IFR AT TIMES.
ANTICIPATE THIS TO END TOWARDS 00Z AS WINDS DIMINISH SOME.
FOR TONIGHT AND TUESDAY MORNING...THE MODELS CONTINUE TO SHOW
STRONG WARM AIR ADVECTION DEVELOPING ACROSS THE REGION. THIS ALONG
WITH A SHORT WAVE TROUGH MOVING FROM THE NORTHERN PLAINS SOUTHEAST
INTO IOWA WILL PRODUCE A 10 TO 15K DECK OF CLOUDS AFTER 07.08Z.
OVERALL THE DEEPEST MOISTURE WITH THIS SYSTEM LOOKS TO BE ACROSS
SOUTHEAST MINNESOTA AND NORTHEAST IOWA. AS A RESULT...EXPECT THE
CEILINGS TO LOWER TO AROUND 5K FEET BY 07.15Z AT KRST. THE
CEILINGS MAY EVEN BECOME MVFR ACROSS NORTHEAST IOWA DURING THIS
TIME.
&&
.CLIMATE...
ISSUED AT 243 PM CST MON JAN 6 2014
SO FAR NO RECORDS HAVE BEEN SET AT EITHER LA CROSSE OR ROCHESTER.
HOWEVER...A FEW RECORD LOW TEMPERATURES WERE SET AT COOPERATIVE
OBSERVER SITES...
BYRON MN...........-24. OLD RECORD -10 IN 2010
FRIENDSHIP WI......-22. OLD RECORD -18 IN 1942
OWEN WI............-26. OLD RECORD -26 IN 1979
WINONA DAM 5A MN...-21 OLD RECORD -12 IN 1942
THE COLDEST THE WIND CHILL GOT TO IN LA CROSSE WAS -48 AND AT
ROCHESTER WAS -53. NEITHER MADE IT INTO THE TOP 10...BUT WERE ONLY
ABOUT 5 DEGREES WARMER THAN THE FEBRUARY 2-3 1996 ARCTIC OUTBREAK.
SEE OUR TOP NEWS STORY ON OUR WEBSITE WWW.WEATHER.GOV/ARX FOR MORE
CLIMATE INFORMATION ON THE COLD.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WIND CHILL WARNING UNTIL NOON CST TUESDAY FOR WIZ017-029-032>034-
041>044-053>055-061.
MN...WIND CHILL WARNING UNTIL NOON CST TUESDAY FOR MNZ079-086>088-
094>096.
IA...WIND CHILL WARNING UNTIL NOON CST TUESDAY FOR IAZ008>011-018-019-
029-030.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BOYNE/AJ
CLIMATE...AJ
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND TUESDAY
ISSUED AT 231 PM CST MON JAN 6 2014
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW ARCTIC HIGH
PRESSURE STRETCHING FROM SOUTHERN SASKATCHEWAN TO THE GULF COAST OF
TEXAS EARLY THIS AFTERNOON. THE POLAR VORTEX IS SHIFTING EAST INTO
MICHIGAN THOUGH THE CORE OF THE EXTREMELY COLD AIR IS CURRENTLY
OVERHEAD. TEMPERATURES HAVE NOT WARMED TOO MUCH SO FAR TODAY...WITH
READINGS HOLDING STEADY FROM THE LOWER TEENS BELOW ZERO ALONG THE
LAKE MICHIGAN SHORELINE TO THE LOWER 20S BELOW ZERO OVER CENTRAL
WISCONSIN. WIND CHILLS REMAIN IN THE 35 TO 45 DEGREES BELOW ZERO
RANGE. AREAS OF THIN CLOUD COVER CONTINUE TO STREAM SOUTHEAST ON
THE BACKSIDE OF THE POLAR VORTEX...WITH A FEW FLURRIES BEING
REPORTED ON AREA OBSERVATION SITES. AS THE ARCTIC AIR
MODIFIES...TEMPS AND WIND CHILLS REMAIN THE MAIN FORECAST
CONCERNS...FOLLOWED BY CLOUDS/FLURRY CHANCES.
TONIGHT...ARCTIC HIGH PRESSURE WILL SLIDE TO THE GULF COAST...BUT
THE SURFACE RIDGE AXIS WILL HANG BACK ACROSS THE NORTHERN
MISSISSIPPI TO CENTRAL CANADA. THOUGH TEMPERATURES WILL BE
MODIFYING ALOFT...BRISK WEST WINDS WILL CONTINUE TO FUNNEL IN THE
EXTREME COLD FROM THE NORTHERN PLAINS. DO NOT HAVE A GOOD HANDLE ON
CLOUD COVER TONIGHT...BUT WITH THIN CLOUDS DROPPING SOUTH OVER
SOUTHERN CANADA AND MINNESOTA...FIGURE THE REGION WILL HAVE PARTLY
CLOUDY CONDITIONS THROUGH THE EVENING BEFORE A SLIGHT BACKING OF THE
WINDS PUSHES IN DRIER AIR IN AFTER MIDNIGHT. WITH THE SUSTAINED
WINDS AND A MODIFYING AIRMASS...TEMPS WILL BE A DEGREE OR TWO WARMER
OVER WESTERN SECTIONS OF THE FORECAST AREA...THOUGH WILL LIKELY BE A
FEW DEGREES COLDER OVER EASTERN SECTIONS. BUT WITH WINDS REMAINING
IN THE 10-15KT RANGE...WIND CHILLS WILL REMAIN IN THE 40 TO 50
DEGREE BELOW ZERO RANGE. THUS NO CHANGE TO HEADLINES.
TUESDAY...THE SURFACE RIDGE AXIS WILL SHIFT SLIGHTLY INTO WESTERN
WISCONSIN IN THE AFTERNOON WITH ONLY MID AND HIGH CLOUDS MOVING
OVERHEAD. THE WEST WINDS WILL NOT BE AS STRONG OR GUSTY AS
TODAY...AND COMBINED WITH FURTHER MODIFYING OF THE ARCTIC
AIRMASS...SHOULD SEE TEMPS ABOUT 10 DEGREES WARMER THAN TODAY
ACCORDING TO THE LEADING GUIDANCE. THE EXTREMELY COLD WIND CHILLS
ARE EXPECTED TO RISE TO BETWEEN 20 TO 30 DEGREES BELOW ZERO BY EARLY
AFTERNOON.
.LONG TERM...TUESDAY NIGHT THROUGH MONDAY
ISSUED AT 231 PM CST MON JAN 6 2014
GRADUALLY IMPROVING TEMPERATURES THIS WEEK WILL BE THE PRIMARY
ISSUE FOLLOWED WITH SOME RESOLUTION WITH A FEW PRECIP CHANCES IN
THE NEAR ZONAL FLOW LATE THIS WEEK AND THROUGH THIS WEEKEND.
FOR STARTERS...ANTICIPATE THE ARCTIC AIR MASS WILL TAKE ITS TIME
TO DEPART THIS WEEK EVEN THOUGH H850 TEMPERATURES INCREASE. VERY
COLD DRY AIR MASS WILL BE RECYCLED BACK NORTH WITH THE RETURN FLOW
THROUGH THURSDAY. ANTICIPATED CLEAR SKIES AND LIGHT WINDS UNDER A
COLD HIGH PRESSURE SYSTEM WILL PROVIDE LARGE DIURNAL CHANGES WITH
SUB ZERO LOW TEMPERATURES CONTINUING INTO THURSDAY MORNING OVER
MOST LOCATIONS.
RETURN SOUTH TO SOUTHWEST FLOW BEGINS LATER THURSDAY SO TEMPS
WILL START TO ASCEND QUICKER WITH TEMPERATURES POSSIBLY REACHING
THE FREEZING MARK THIS WEEKEND OVER PARTS OF THE AREA. CLOUDS MAY
BE ON THE INCREASE OVER SOUTHERN WISCONSIN THROUGH THURSDAY WITH
THE PASSAGE OF A SOUTHERN STREAM SYSTEM TO THE SOUTH...BUT EXPECT THE
AREA TO REMAIN DRY WITH THE SURFACE HIGH STILL SETTLED OVER THE
AREA.
MODEL TIMING OF VARIOUS SHORT WAVES IN THE NEAR ZONAL FLOW POINTING
TO A FRIDAY INTO FRIDAY NIGHT TIME FRAME. A WEAK RIDGE SETTLES
OVER SATURDAY INTO SUNDAY BEFORE POSSIBLY ANOTHER WEAK SYSTEM
PASSES OVER LATER SUNDAY. AGAIN MODEL TIME IN QUESTION DUE TO
TIMING OF THESE SHORT WAVES IN THE ZONAL FLOW AND LIKELY WILL NEED
FURTHER ADJUSTMENTS.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1101 AM CST MON JAN 6 2014
MAINLY VFR CONDITIONS THROUGH THE TAF PERIOD WITH VARIABLE CIGS.
KEPT SCT-BKN CLOUDS AROUND THROUGH THE EVENING SINCE CLOUDS ARE
HANGING AROUND OVER MINNESOTA. BUT DO THINK CLEARING WILL OCCUR
AFTER MIDNIGHT. AS TEMPERATURES MODERATE ALOFT...A STRONG INVERSION
WILL DEVELOP WHICH WILL PROMOTE INCREASING LOW LEVEL WIND SHEAR.
WESTERLY SURFACE WINDS WILL REMAIN RATHER GUSTY THROUGH THE
AFTERNOON...AND THEN DIMINISH SOMEWHAT AT NIGHT. JUST A FEW HIGH
CLOUDS ON TUESDAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
WIND CHILL WARNING UNTIL NOON CST TUESDAY FOR WIZ005-010>013-
018>022-030-031-035>040-045-048>050-073-074.
&&
$$
SHORT TERM.....MPC
LONG TERM......TDH
AVIATION.......MPC