Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/14/14
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
827 PM MST MON JAN 13 2014
.UPDATE...
&&
.SHORT TERM...HIGH WINDS HAVE REDEVELOPED EARLY THIS EVENING IN
THE FOOTHILLS OF BOULDER AND JEFFERSON COUNTIES WITH GUSTS AOB 80
MPH IN A FEW SPOTS SO HAVE REISSUED THE WARNING THRU 11Z TUE
MORNING.
MEANWHILE A STG CDFNT IS MOVING RAPIDLY SOUTH ACROSS NERN WY WHERE
WINDS GUSTS OF 50 TO 60 MPH HAVE OCCURRED BRIEFLY WITH FNT. AM A
LITTLE CONCERNED AS THIS FNT MOVES INTO NERN CO TUE MORNING IF
LOW LVL FLOW TURNS MORE NNE THIS COULD ENHANCE SNOWFALL CLOSER TO
THE FRONT RANGE AND OVER THE PALMER DIVIDE AS DISTURBANCE IN NW
FLOW ALOFT MOVES ACROSS. RIGHT NOW LATEST GUIDANCE KEEPS THE BEST
CHC OF SNOW MAINLY FM GREELEY TO JUST EAST OF DENVER SE ACROSS
PORTIONS OF ELBERT COUNTY. SOME AREAS COULD QUICKLY PICK UP FROM
1 TO 3 INCHES OF SNOW IN THIS BAND.
.AVIATION...WINDS MAY STAY MORE WLY OVERNIGHT UNTIL FNT GETS
CLOSER BY 10Z OR SO. WINDS WILL THEN TURN MORE NLY WITH GUSTS
BRIEFLY IN THE 35-40 MPH RANGE FOR AN HOUR OR SO. FOR NOW WILL
KEEP BEST CHC OF SNOW JUST EAST OF THE AIRPORT. HOWEVER AS TALKED
ABV MAIN BAND OF SNOW COULD END UP A LITTLE FURTHER WEST AND OVER
THE AIRPORT IF THE WINDS TURN MORE NNE.
&&
.PREV DISCUSSION... /ISSUED 352 PM MST MON JAN 13 2014/
SHORT TERM...WINDS STILL GUSTY ACROSS HIGHER MOUNTAINS AND ALONG
FOOTHILLS. CURRENT GUST OF 73 MPH IN THE SUGARLOAF MOUNTAIN AREA.
GUSTS HAVE BEEN SLOWLY DECREASING IN RESPONSE TO WEAKENING
GRADIENT FROM GRAND JUNCTION TO DENVER AND JET MAX SHIFTING INTO
PLAINS STATES. LATEST HRRR AND RAP SHOW GUSTS CONTINUING TO
DECREASE BY 00Z...WITH SPATIAL CROSS SECTIONS SHOWING CROSS
MOUNTAIN FLOW AROUND 45 KTS AT MOUNTAIN TOP AT THAT TIME. WINDS
WILL CONTINUE TO DECREASE THROUGH THE EVENING. WILL ALLOW HIGH
WIND WARNING TO EXPIRE AT 23Z. AS FOR SNOW...WEB CAMS STILL
SHOWING SOME LIGHT SNOW ALONG THE CONTINENTAL DIVIDE OF SUMMIT AND
GRAND COUNTIES...THOUGH CONDITIONS HAVE BEEN SLOWLY IMPROVING.
SNOTEL DATA INDICATING SNOW ALSO OCCURRING ACROSS ZONE 31. AREAS
OF BLOWING SNOW STILL ONGOING ACROSS MOST OF THE HIGH
COUNTRY...MAINLY HIGHER MOUNTAIN PASSES. MODEL CROSS SECTIONS SHOW
MOISTURE INCREASING ACROSS THE MOUNTAINS BY MIDNIGHT AS WEAK MID
LEVEL DISTURBANCE MOVES ACROSS WYOMING. THIS SHOULD KEEP SOME SNOW
GOING ACROSS THE MOUNTAINS...MAINLY NORTH OF INTERSTATE 70. BEST
LIFT TO BE ACROSS NORTHWEST COLORADO. WILL KILL THE WINTER STORM
WARNING FOR ZONES 33 AND 34 WITH THIS ISSUANCE...AND HOIST A SNOW
AND BLOWING SNOW ADVISORY FOR ZONE 31 THROUGH 18Z TUESDAY WITH AN
ADDITIONAL 3 TO 6 INCHES ALONG WITH AREAS OF BLOWING SNOW. LESS
SNOW EXPECTED FOR REST OF MOUNTAINS THOUGH AREAS OF BLOWING SNOW
SHOULD PERSIST. ACROSS PLAINS...WINDS TO DECREASE DURING THE
EVENING AS SURFACE PRESSURE BEGINS TO RISE AHEAD OF AN APPROACHING
FRONT. THIS FRONT ASSOCIATED WITH THE UPPER LEVEL DISTURBANCE WILL
PUSH INTO NORTHEAST COLORADO AFTER MIDNIGHT. APPEARS FRONT SHOULD
REACH DENVER AREA AROUND 11Z WITH WIND SHIFT TO THE NORTH. SOME
INCREASE IN MID LEVEL MOISTURE OVERNIGHT. WITH JET ACROSS CENTRAL
PLAINS STATES...THERE WILL BE A CHANCE FOR LIGHT SNOW ACROSS
NORTHEAST COLORADO AND THE POTENTIAL FOR BANDED SNOWFALL AROUND
12Z. AT THIS TIME IT LOOKS LIKE THE BANDED SNOWFALL WILL OCCUR
NORTHEAST OF DENVER...BUT THERE IS A CHANCE THAT THIS BAND COULD
END UP FURTHER WEST TUESDAY MORNING. WILL GO WITH THE CHANCE POPS
FOR MOST OF NORTHEAST CO FOR NOW. ANY ACCUMULATION SHOULD BE LESS
THAT ONE HALF INCH. MOISTURE AND WINDS WILL BE ON THE DECREASE
ACROSS THE MOUNTAINS DURING THE DAY TUESDAY MINIMAL ACCUMULATIONS
ON WEST FACING SLOPES. ACROSS PLAINS. SNOW CHANCES TO END BY 20Z
SOME INCREASE IN NORTHWEST WINDS. AIRMASS ACROSS PLAINS TO BE
COOLER WITH HIGHS AROUND 40 DEGREES.
LONG TERM...A DRY AND SUBSIDENT AIRMASS WILL BUILD OVER THE
FORECAST AREA THROUGH TOMORROW NIGHT AND WEDNESDAY. ANY SNOW
SHOWERS TRAPPED IN THE HIGH MOUNTAINS WILL BE ENDING DURING THE
EVENING AS AIRMASS DRIES SIGNIFICANTLY. WITH REGARD TO
WIND...CROSS MOUNTAIN COMPONENT DECREASES TO ABOUT 30 KTS...BUT A
MEAN STATE CRITICAL LAYER DEVELOPS. THIS MAY RESULT IN TRAPPED
MOUNTAIN WAVE ENERGY REACHING THE FOOTHILLS...SO WILL CONTINUE THE
GUSTY WIND FORECAST IN/NEAR THE FRONT RANGE MOUNTAINS AND
FOOTHILLS. PLAINS WINDS SHOULD GRADUALLY RELAX AS MIXING DECREASES
OVERNIGHT TUESDAY NIGHT...BUT THEN STRENGTHEN AGAIN WEDNESDAY WITH
DAYTIME HEATING AND MIXING. TEMPERATURES WILL TURN WARMER WITH
STRONG WARM ADVECTION AND 700 MB READINGS WARMING TO NEAR 0C. THIS
WOULD SUPPORT WEDNESDAYS HIGHS WELL INTO THE 50S AND POSSIBLY 60F
ALONG THE FRONT RANGE.
BY THURSDAY...ANOTHER FRONT IS EXPECTED TO REACH THE FORECAST AREA
WITH MORE GUSTY WINDS BUT COOLER TEMPERATURES. NO PRECIPITATION IS
EXPECTED AT THIS TIME AS AIRMASS REMAINS TOO DRY.
WARMER WEATHER WILL THEN REDEVELOP BY FRIDAY AND LIKELY LAST
THROUGH THE WEEKEND WITH UPPER RIDGE BUILDING TO OUR WEST. THERE
IS STILL WEAK TO MODERATE NORTHWEST FLOW ALOFT THOUGH...SO WE WONT
BE TOTALLY IMMUNE TO WEAK FRONTS BACKING ACROSS THE PLAINS.
OVERALL...TEMPERATURES SHOULD AVERAGE SEVERAL DEGREES ABOVE
NORMAL. PERHAPS A LITTLE MORE SIGNIFICANT BUT BRIEF COOLING IS
ADVERTISED TO REACH THE AREA BY EARLY NEXT WEEK...BUT EVEN THEN
READINGS LOOK TO BE NEAR NORMAL. NO PRECIPITATION IS EXPECTED
DURING THIS PERIOD AS WELL.
AVIATION...GUSTY WEST TO NORTHWEST WINDS ACROSS AREA AIRPORTS TO
GRADUALLY DECREASE THROUGH THE EVENING...TRENDING TOWARD DRAINAGE
BY 03Z. SOME GUSTS TO 40 KTS STILL POSSIBLE AT KBJC THROUGH 02Z.
WINDS TO THEN SHIFT TO THE NORTHWEST AROUND 08Z AHEAD OF AN
APPROACHING COLD FRONT. THE FRONT IS EXPECTED TO MOVE ACROSS THE
AREA AIRPORTS AROUND 11Z WITH A WIND SHIFT TO THE NORTH. MID LEVEL
MOISTURE WILL INCREASE AFTER MIDNIGHT AND GRADUALLY LOWER AROUND
10Z. CEILINGS OF AROUND 6000 FEET AGL WITH BE POSSIBLE BETWEEN 11Z
AND 16Z ALONG WITH A CHANCE FOR LIGHT SNOW. AT THIS TIME...VFR
CONDITIONS SHOULD PREVAIL. AFTER 18Z WINDS TO SHIFT TO THE
NORTHWEST WITH DECREASING CLOUDS. SOME GUSTS TO 20 KTS WILL BE
POSSIBLE...MAINLY AT KDEN AND KBJC.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL 4 AM MST TUESDAY FOR COZ035-036.
WINTER WEATHER ADVISORY UNTIL NOON MST TUESDAY FOR COZ031.
&&
$$
SHORT TERM...RPK
LONG TERM....BARJENBRUCH
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1009 AM MST SUN JAN 12 2014
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 308 AM MST SUN JAN 12 2014
SURFACE COLD FRONT STRETCHED FROM WRN WY ACROSS NRN UT TO SRN NV AT
09Z. REGIONAL RADARS SHOWED PRECIP GENERALLY CONFINED TO ALONG AND
BEHIND THE FRONT...WITH RAIN REPORTED AT SLC. THE UPPER LOW CENTER
WAS CROSSING THE NRN ROCKIES WITH AN EAST-SOUTHEAST PUSH TO THE
ASSOCIATED TROUGH EXTENDING DOWN TO NRN NV. WHERE GUSTY WINDS
DEVELOP AT THE SURFACE...THE TURBULENT MIXING HAS RESULTED IN TEMPS
EXHIBITING A SPIKE UPWARDS. MEEKER AND CRAIG BOTH TOUCHED 40F
EARLIER IN THE NIGHT WHEN THIS OCCURRED.
PRECIPITATION HAS BE SLOW TO START OVER OUR AREA THOUGH STRONG
LOW-LEVEL WARM ADVECTION LIKELY PUTTING AT LEAST SOME AREAS OF LIGHT
SNOW OVER THE HIGHER ELEVS OF THE ERN UINTAS AND NRN CO MTNS. A FEW
MTN SNOTEL SITES REGISTERING LIGHT AMOUNTS SUPPORT THIS. CLOUDS
BASES HAVE BEEN SLOWLY LOWERING...SO SUSPECT THAT PRECIP WILL BE
RAMPING UP BY 12Z WHEN THE RUC13 MODEL HAS THE FRONT REACHING A
MOAB-CRAIG LINE....AND THEN TO THE SAN JUANS BY MIDDAY. AS THE UPPER
JET ON THE FRONT SIDE OF THE TROUGH MOVES OVERHEAD...THE COMBINATION
OF DYNAMICS AND FRONTAL LIFT WITH DEEP INSTABILITY SHOULD BRING
WIDESPREAD SNOW TO THE MOUNTAINS AND TO MANY NORTHERN AND CENTRAL
VALLEYS THIS MORNING. STRONG WINDS ALOFT WITH GUSTY WINDS AT THE
SURFACE WILL PRODUCE AREAS OF BLOWING SNOW ACROSS THE NORTH AND
CENTRAL AREAS. STRONGEST WINDS SHOULD BE OVER THE FLATTOPS AND
ELKHEAD/PARK/GORE MTNS. SNOW AND BLOWING SNOW WILL MAKE TRAVEL VERY
DIFFICULT OVER RABBIT EARS AND VAIL PASSES THIS AFTERNOON AND
EVENING...AND PROBABLY MONDAY TOO.
AS THE FRONT AND UPPER TROUGH MOVE PAST... FORCING BECOMES MORE
OROGRAPHICALLY DRIVEN AS NORTHWEST FLOW SETS UP THIS AFTERNOON AND
EVENING. PRECIPITABLE WATER AND SPECIFIC HUMIDITY VALUES DROP QUICKLY
BEHIND THE FRONT TODAY...BUT THE NAM/GFS MAINTAIN A MOIST DENDRITIC
SNOW GROWTH LAYER ACROSS THE NRN MTNS WITH A SECOND PUSH OF MOISTURE
TONIGHT THAT SHOULD HELP MAINTAIN SNOW THERE INTO MONDAY.
ASIDE FROM THE BIT SLOWER START TO PRECIPITATION...THE CURRENT
FORECAST GRIDS AND WINTER HIGHLIGHTS LOOK ON TRACK. MADE ONLY MINOR
CHANGES SUCH AS TO EXPAND BLOWING SNOW IN THE GRIDS INTO MORE OF
THE NW CO VALLEYS TODAY
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 308 AM MST SUN JAN 12 2014
NWLY FLOW WILL KEEP SOME SNOW SHOWERS IN THE PICTURE FOR THE NRN
MTNS THOUGH ACCUMULATIONS WILL BE ON THE LIGHT SIDE MONDAY NIGHT
INTO TUESDAY. BOTH THE GFS AND NAM HIGHLIGHT THIS PRECIP THROUGH TUE
AFTN SO KEPT CHCS FOR PRECIP IN FORECAST. AFTER THAT...A LARGE
RIDGE OF HIGH PRESSURE TO THE WEST WILL BUILD IN KEEPING OUR CWA
HIGH AND DRY THROUGH THE REMAINDER OF THE FORECAST PERIOD. SOME
DISCREPANCIES POP UP TOWARDS THE WEEKEND BTWN THE EC AND GFS BUT
LOW CONFIDENCE IN FORECAST AS SOLNS ARE SO FAR OUT.
EXPECT TEMPERATURES TO CLIMB A FEW DEGREES ABOVE NORMAL FOR THIS
TIME OF YEAR FROM TUESDAY ONWARDS EXCEPT FOR THOSE VALLEYS WHERE
INVERSIONS SET UP...THE GRAND VALLEY...TELLURIDE AND DURANGO TO
NAME A FEW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY NOON)
ISSUED AT 1010 AM MST SUN JAN 12 2014
AT 10AM THE COLD FRONT HAD WORKED INTO THE SAN JUAN MOUNTAINS AND
WILL PUSH SOUTHEAST OF THE ENTIRE FORECAST AREA BY EARLY
AFTERNOON. CONVECTIVE SNOW SHOWERS WILL BE WIDESPREAD THROUGH 00Z
FOR ALL TAF SITES EXCEPT DRO. IN SHOWERS EXPECT CIGS AOB 010 AND
VSBY AOB 1SM. MOUNTAINS WILL BE FQTLY OBSCURED. BY THIS
EVENING...SNOWFALL WILL CONTINUE FOR THE NRN AND CENTRAL MTNS. FOR
KHDN...KSBS...KEGE...KASE EXPECT CIGS BLOW 030 VSBY BLO 3SM IN SN
BR. ALONG WITH SNOW...EXPECT GUSTY WINDS WITH SOME BLOWING SNOW
EXPECTED ALSO DROPPING VISIBILITIES. STRONGER WINDS CAN BE
EXPECTED AT HIGHER ELEVATIONS CAUSING SOME MECHANICAL TURBULENCE
WHILE MTN OBSCURATIONS WILL BE COMMON TONIGHT THROUGH MONDAY
MORNING.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL 9 PM MST THIS EVENING COZ008-014.
WINTER STORM WARNING UNTIL MIDNIGHT MST TONIGHT COZ009-012-018.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT MST TONIGHT COZ003-017.
WINTER STORM WARNING UNTIL 5 PM MST MONDAY COZ004-010-013.
WINTER STORM WARNING UNTIL 3 AM MST MONDAY COZ005.
WINTER STORM WARNING UNTIL 5 PM MST THIS AFTERNOON COZ002.
UT...NONE.
&&
$$
SHORT TERM...JAD
LONG TERM...TGR
AVIATION...TGR
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
855 AM MST SUN JAN 12 2014
.UPDATE...
&&
.SHORT TERM...UPPER LEVEL TROF OVER EASTERN UTAH AND STRONG JET
MOVING OVER COLORADO WITH BATCH OF HEAVY SNOW DEVELOPING OVER
NORTH CENTRAL MOUNTAINS. WARNINGS ALREADY IN PLACE AND ONGOING
FORECAST LOOKS GOOD IN THE MOUNTAINS. SURFACE FRONT CONTINUES TO
PUSH SOUTH OVER THE DENVER AREA WITH GUSTY NORTHERLY WINDS
DEVELOPING BEHIND IT. THIS TIMING IS A LITTLE QUICKER THAN
PREVIOUS FORECAST SO HAVE BEEFED UP THE WINDS THIS MORNING. WITH
COLD ADVECTION THIS AFTERNOON...GOOD MIXING WILL ALLOW STRONG NW
WINDS TO DEVELOP OVER MUCH OF THE AREA. COULD CERTAINLY SEE SOME
GUSTS IN THE 30-50 MPH RANGE AND HAVE ALSO INCREASED THE WINDS ON
THE PLAINS. LATEST RAP AND HRRR SHOWING SOME QPF OVER THE PALMER
DIVIDE AND EAST AND SOUTH OF DENVER. SO HAVE ADDED SOME LOW POPS
FOR NOW.
.AVIATION...SURFACE FRONT PUSHING SOUTH THROUGH TERMINAL WITH
NORTH TO NORTHEAST WINDS BEHIND IT. WINDS WILL DIMINISH A BIT LATE
AM BEFORE INCREASING AGAIN FROM THE NORTHWEST THIS AFTERNOON WITH
STRONG MIXING EXPECTED IN THE LOW LEVELS. WILL LEAVE TERMINALS DRY
FOR NOW BUT WILL HAVE TO WATCH THE SHOWER DEVELOPMENT POSSIBLE
EAST AND SOUTH OF APA.
&&
.PREV DISCUSSION... /ISSUED 259 AM MST SUN JAN 12 2014/
SHORT TERM...FOR TODAY...A STRONG WESTERLY FLOW ALOFT WILL BE
OVER THE CWFA AS THE NEXT STORM SYSTEM PASSES ACROSS CO. THE
TROUGH AXIS WILL MOVE ACROSS EASTERN COLORADO BY EARLY AFTERNOON
WITH THE FLOW ALOFT BECOMING MORE WNWLY. SNOWFALL WILL REDEVELOP
ACROSS THE NORTH CENTRAL MOUNTAINS THIS MORNING...WITH INCREASING
MID AND UPPER LEVEL QG ASCENT AHEAD OF THE TROUGH AXIS. IN
ADDITION AN 110KT JET MAX WILL SHIFT ACROSS CO THIS MORNING AHEAD
OF THE TROUGH. STRONG WINDS HAVE PERSISTED OVERNIGHT WITH GUSTS TO
NEAR 80 MPH AOA 12K FT. BY THIS AFTN...STRONG QG DESCENT AND MID
LEVEL COLD AIR ADVECTION KICKS IN. BORA TYPE SETUP WITH STRONG
WINDS AND SNOW IN THE MOUNTAINS...ESPECIALLY THIS AFTN AND
EVENING. PERIOD OF THE BEST SNOW WILL BE FM BETWEEN 18Z THIS AFTN
AND 06Z TONIGHT. AS A RESULT...NO CHANGES REGARDING THE WINTER
STORM WARNING FOR TODAY AND TONIGHT. SNOWFALL WILL BE DRIVEN BY
PRIMARILY OROGRAPHICS AFTER 21Z THIS AFTN...WITH HEAVIEST SNOWFALL
EXPECTED ALONG WEST FACING SLOPES. THE HIGH WIND THREAT FOR THE
FOOTHILLS WILL RETURN THIS AFTN AND TONIGHT. MOUNTAIN WAVE
REDEVELOPS TONIGHT...WITH THE MOST FAVORABLE WAVE AMPLIFICATION
AFTER 06Z TONIGHT. STRONG BORA WINDS THIS AFTN AND EVENING WILL BE
A PRODUCT OF STRONG WINDS ALOFT...AND DOWNWARD TRANSPORT THROUGH
SUBSIDENCE AND MIXING THRU COLD AIR ADVECTION. OVERNIGHT TONIGHT
..KDEN-KGJT SFC PRESSURE GRADIENT WILL INTENSIFY WITH RIDGETOP
WINDS OF 70KTS WITH A MEAN STATE CRITICAL LAYER OF 10KTS OR LESS
AT 550 MB. FOR THE URBAN CORRIDOR AND NORTHEAST PLAINS...DRY BUT
VERY WINDY THIS AFTN FOLLOWING THE PASSAGE OF THE MID LEVEL TROUGH
AXIS. THE WIND WILL BE STRONGEST NEAR THE FOOTHILLS AND NEAR THE
WYOMING AND NEBRASKA BORDERS. ZONES 38 AND 39 WILL NEED TO BE
MONITORED FOR HIGH WIND ESPECIALLY AFTER MIDNIGHT TONIGHT. FOR
NOW...WILL STICK WITH THE CURRENT HIGHLIGHTS AND LET THE DAY SHIFT
ASSESS THE WIND POTENTIAL THERE.
LONG TERM...MONDAY THROUGH SATURDAY...THE LARGE SCALE WEATHER
PATTERN WILL STAGNATE NEXT WEEK ACROSS THE COUNTRY. A LONG WAVE
TROUGH WILL BE OVER THE EASTERN PART OF THE COUNTRY WITH A RIDGE
OVER THE WESTERN STATES. THIS PATTERN WILL LEAVE COLORADO UNDER A
NORTHWESTERLY FLOW THROUGH THE WEEK.
A STRONG AND SOMEWHAT MOIST NORTHWEST FLOW ALOFT WILL REMAIN OVER
THE MOUNTAINS MONDAY BEHIND THE EXITING TROUGH. MOISTURE BECOMES
SHALLOW DURING THE AFTERNOON HOURS. EXPECT SNOW TO DECREASE IN
COVERAGE AND INTENSITY THROUGH THE DAY MONDAY. WILL KEEP THE WINTER
STORM WARNING AS IS...THOUGH IT WILL LIKELY NEED TO BE ENDED A
LITTLE SOONER.
PATCHY OROGRAPHIC LIGHT SNOW WILL CONTINUE MONDAY NIGHT AND TUESDAY.
BECAUSE OF DECREASING MOISTURE AND A MORE NORTHERLY WIND COMPONENT
EXPECT ANY SNOWFALL TO BE LIGHT. A SHORT WAVE TROUGH EMBEDDED IN THE
NORTHWEST FLOW ALOFT WILL MOVE SOUTH ACROSS THE PLAINS STATES
TUESDAY. THE JET AXIS WILL MOVE OVER EASTERN COLORADO EARLY TUESDAY.
THE NORTHEAST CORNER OF THE STATE WILL BE UNDER THE FRONT LEFT
QUADRANT OF THE JET. WILL ADDED SOME LOW POPS INTO THE FORECAST FOR
THIS. EXPECT THIS SYSTEM TO BRING WINDY CONDITIONS TO THE NORTHEAST
PLAINS. IN ADDITION TO THE WINDS...TEMPERATURES WILL BE COOLER
TUESDAY.
TEMPERATURES REBOUND ON WEDNESDAY WITH MANY LOCATIONS OVER NORTHEAST
COLORADO CLIMBING ABOVE 50 DEGREES. ANOTHER STRONG WAVE WILL DIVE
SOUTH ACROSS THE PLAINS STATES THURSDAY. THIS WILL BRING COOLER
TEMPERATURES AND ANOTHER ROUND OF WINDY CONDITIONS ACROSS THE
NORTHEAST PLAINS.
FLOW ALOFT WILL WEAKEN FRIDAY AND SATURDAY AS THE UPPER LEVEL RIDGE
OVER THE WESTERN STATES STARTS TO SHIFT EASTWARD. THIS WILL BRING
MILD AND DRY CONDITIONS. TEMPERATURES BY SATURDAY SHOULD CLIMB INTO
THE 50S ACROSS NORTHEAST COLORADO.
AVIATION...VFR CONDITIONS OVER THE NEXT 24 HRS. LIGHTER SLY WIND
COMPONENT WAFFLING FM SE-SWLY THIS MORNING. SHOULD SEE WINDS
INCREASE AND BECOME SWLY AFTN 15Z THIS MORNING...THEN PICK UP FM
THE WEST/NORTHWEST 17-18Z FOLLOWING FROPA. GENERAL 15-25 KTS WITH
SOME GUSTS TO 35 KTS FM 20Z-01Z. WINDS WILL DECREASE THIS EVENING
BUT PERSISTENT WSWLY DIRECTION OVERNIGHT. AT KBJC STRONG WINDS
WILL DEVELOP THIS AFTN AND CONTINUE TONIGHT. STRONGEST WIND WILL
BE THIS AFTN AND LATE TONIGHT...AFTER 06Z WITH GUSTS OF 50+ KTS
PSBL AT THAT TIME.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 5 PM MST MONDAY FOR COZ031-033-034.
HIGH WIND WARNING FROM 2 PM THIS AFTERNOON TO 11 AM MST MONDAY
FOR COZ035-036.
WINTER WEATHER ADVISORY UNTIL 8 PM MST THIS EVENING FOR COZ030-
032.
&&
$$
SHORT TERM...ENTREKIN
LONG TERM....MEIER
AVIATION...ENTREKIN
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
309 AM MST SUN JAN 12 2014
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 308 AM MST SUN JAN 12 2014
SURFACE COLD FRONT STRETCHED FROM WRN WY ACROSS NRN UT TO SRN NV AT
09Z. REGIONAL RADARS SHOWED PRECIP GENERALLY CONFINED TO ALONG AND
BEHIND THE FRONT...WITH RAIN REPORTED AT SLC. THE UPPER LOW CENTER
WAS CROSSING THE NRN ROCKIES WITH AN EAST-SOUTHEAST PUSH TO THE
ASSOCIATED TROUGH EXTENDING DOWN TO NRN NV. WHERE GUSTY WINDS
DEVELOP AT THE SURFACE...THE TURBULENT MIXING HAS RESULTED IN TEMPS
EXHIBITING A SPIKE UPWARDS. MEEKER AND CRAIG BOTH TOUCHED 40F
EARLIER IN THE NIGHT WHEN THIS OCCURRED.
PRECIPITATION HAS BE SLOW TO START OVER OUR AREA THOUGH STRONG
LOW-LEVEL WARM ADVECTION LIKELY PUTTING AT LEAST SOME AREAS OF LIGHT
SNOW OVER THE HIGHER ELEVS OF THE ERN UINTAS AND NRN CO MTNS. A FEW
MTN SNOTEL SITES REGISTERING LIGHT AMOUNTS SUPPORT THIS. CLOUDS
BASES HAVE BEEN SLOWLY LOWERING...SO SUSPECT THAT PRECIP WILL BE
RAMPING UP BY 12Z WHEN THE RUC13 MODEL HAS THE FRONT REACHING A
MOAB-CRAIG LINE....AND THEN TO THE SAN JUANS BY MIDDAY. AS THE UPPER
JET ON THE FRONT SIDE OF THE TROUGH MOVES OVERHEAD...THE COMBINATION
OF DYNAMICS AND FRONTAL LIFT WITH DEEP INSTABILITY SHOULD BRING
WIDESPREAD SNOW TO THE MOUNTAINS AND TO MANY NORTHERN AND CENTRAL
VALLEYS THIS MORNING. STRONG WINDS ALOFT WITH GUSTY WINDS AT THE
SURFACE WILL PRODUCE AREAS OF BLOWING SNOW ACROSS THE NORTH AND
CENTRAL AREAS. STRONGEST WINDS SHOULD BE OVER THE FLATTOPS AND
ELKHEAD/PARK/GORE MTNS. SNOW AND BLOWING SNOW WILL MAKE TRAVEL VERY
DIFFICULT OVER RABBIT EARS AND VAIL PASSES THIS AFTERNOON AND
EVENING...AND PROBABLY MONDAY TOO.
AS THE FRONT AND UPPER TROUGH MOVE PAST... FORCING BECOMES MORE
OROGRAPHICALLY DRIVEN AS NORTHWEST FLOW SETS UP THIS AFTERNOON AND
EVENING. PRECIPITABLE WATER AND SPECIFIC HUMIDITY VALUES DROP QUICKLY
BEHIND THE FRONT TODAY...BUT THE NAM/GFS MAINTAIN A MOIST DENDRITIC
SNOW GROWTH LAYER ACROSS THE NRN MTNS WITH A SECOND PUSH OF MOISTURE
TONIGHT THAT SHOULD HELP MAINTAIN SNOW THERE INTO MONDAY.
ASIDE FROM THE BIT SLOWER START TO PRECIPITATION...THE CURRENT
FORECAST GRIDS AND WINTER HIGHLIGHTS LOOK ON TRACK. MADE ONLY MINOR
CHANGES SUCH AS TO EXPAND BLOWING SNOW IN THE GRIDS INTO MORE OF
THE NW CO VALLEYS TODAY
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 308 AM MST SUN JAN 12 2014
NWLY FLOW WILL KEEP SOME SNOW SHOWERS IN THE PICTURE FOR THE NRN
MTNS THOUGH ACCUMULATIONS WILL BE ON THE LIGHT SIDE MONDAY NIGHT
INTO TUESDAY. BOTH THE GFS AND NAM HIGHLIGHT THIS PRECIP THROUGH TUE
AFTN SO KEPT CHCS FOR PRECIP IN FORECAST. AFTER THAT...A LARGE
RIDGE OF HIGH PRESSURE TO THE WEST WILL BUILD IN KEEPING OUR CWA
HIGH AND DRY THROUGH THE REMAINDER OF THE FORECAST PERIOD. SOME
DISCREPANCIES POP UP TOWARDS THE WEEKEND BTWN THE EC AND GFS BUT
LOW CONFIDENCE IN FORECAST AS SOLNS ARE SO FAR OUT.
EXPECT TEMPERATURES TO CLIMB A FEW DEGREES ABOVE NORMAL FOR THIS
TIME OF YEAR FROM TUESDAY ONWARDS EXCEPT FOR THOSE VALLEYS WHERE
INVERSIONS SET UP...THE GRAND VALLEY...TELLURIDE AND DURANGO TO
NAME A FEW.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 308 AM MST SUN JAN 12 2014
CONDITIONS WILL DETERIORATE AS THE DAY PROGRESSES FOR MOUNTAINOUS
TERRAIN. ANTICIPATE MVFR TO IFR CONDITIONS FOR KSBS...KCAG...KHDN
AND SIMILAR CONDITIONS FOR KASE AND KEGE THOUGH ALL TAF SITES MAY
SEE SOME BRIEF SNOW AS A COLD FRONT MOVES ACROSS THE REGION TODAY.
ONCE THE FRONT HAS MOVED THROUGH BY THIS EVENING...SNOWFALL WILL
CONTINUE FOR THE NRN AND CENTRAL MTNS. ALONG WITH SNOW...EXPECT
GUSTY WINDS WITH SOME BLOWING SNOW EXPECTED ALSO DROPPING VISIBILITIES.
STRONGER WINDS CAN BE EXPECTED AT HIGHER ELEVATIONS CAUSING SOME
MECHANICAL TURBULENCE WHILE MTN OBSCURATIONS WILL BE COMMON TODAY
AND TONIGHT.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL 9 PM MST THIS EVENING COZ008-014.
WINTER STORM WARNING UNTIL MIDNIGHT MST TONIGHT COZ009-012-018.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT MST TONIGHT COZ003-017.
WINTER STORM WARNING UNTIL 5 PM MST MONDAY COZ004-010-013.
WINTER STORM WARNING UNTIL 3 AM MST MONDAY COZ005.
WINTER WEATHER ADVISORY UNTIL 5 PM MST THIS AFTERNOON COZ002.
UT...NONE.
&&
$$
SHORT TERM...JAD
LONG TERM...TGR
AVIATION...TGR
AREA FORECAST DISCUSSION
NWS TAUNTON MA
344 AM EST SUN JAN 12 2014
.SYNOPSIS...
WEAK AREA OF HIGH PRESSURE WILL MOVE SOUTH OF THE REGION TODAY
INTO TOMORROW. THIS WILL BRING A PERIOD OF GUSTY WINDS TODAY...BUT
MILD TEMPERATURES BOTH TODAY AND TOMORROW. A PERIOD OF UNSETTLED
WEATHER IS EXPECTED TUE AND AGAIN LATE WED OR WED NIGHT AS A
SERIES OF LOW PRESSURE SYSTEMS MOVES INTO THE REGION. HIGH PRES
RETURNS THU THEN A STRONG COLD FRONT WILL BRING BELOW NORMAL
TEMPERATURES THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SFC COLD FRONT CURRENTLY DRAPED FROM JUST S OF BOS SW TO CENTRAL
CT AND CONTINUING TO MOVE E. THIS SHOULD BE OFFSHORE BY AROUND
11-12Z. PWATS AHEAD OF THIS FRONT STILL HOVERING AROUND 1.0 INCHES
SO THE FRONT IS PROVIDING JUST ENOUGH LIFT TO KEEP SOME LIGHT TO
MOD -SHRA GOING. THESE TOO WILL BE GRADUALLY ENDING BY ABOUT 12Z
SO HAVE TIMED POPS ACCORDINGLY...BASED MAINLY ON A BLEND OF HRRR
AND RAP WHICH ARE HANDLING THE CURRENT -SHRA BANDS WELL.
OTHERWISE...AM ALREADY NOTING SOME CLEARING ACROSS WRN INTERIOR
ZONES BUT THE MIXING PROVIDED BY THE FRONT AND THE MID LVL COLD
ADVECTION HAVE KEPT TEMPS FROM DROPPING OFF TOO FAST. ONLY SOME
UPPER 30S APPARENT IN NW MASS AND SW NH. THEREFORE...SUSPECT MANY
LOCATIONS WILL STILL BE IN THE MID 30S TO MID 40S BY DAYBREAK WITH
ENOUGH CLEARING BY THEN THAT MUCH OF THE REGION SHOULD SEE
SUNSHINE EARLY. THEREFORE...MIXING SHOULD BE ESTABLISHED EARLY AND
WITH TEMPS ABOVE NORMAL...SUSPECT MIXING TO COME CLOSE TO TAPPING
H85. TEMPS MAY CONTINUE TO DROP THROUGH ABOUT MID MORNING BUT
MIXING SHOULD ALLOW THEM TO START TO RISE AGAIN INTO THE
AFTERNOON...WITH MAX VALUES RANGING FROM THE LOW 40S TO CLOSE TO
50 IN THE COASTAL PLAIN OF MA.
THE MAIN ISSUE WITH THESE ANOMALOUSLY WARM TEMPS AND DECENT MIXING
IS THAT GUIDANCE CONTINUES TO BE FAIRLY CONSISTENT WITH A 40-45
KT WSW WIND SPEED MAX AT THIS LEVEL...WHICH PEAKS MID AFTERNOON.
THEREFORE...FEEL THIS MOMENTUM WILL BE TAPPED. THE MAIN CORE OF
THE MAX FALLS MAINLY ACROSS WRN MA AND SRN NH. THEREFORE...WILL BE
ISSUING A WIND ADVISORY FOR WINDS AROUND 45 MPH THROUGH THE
DAYLIGHT HOURS. FOR NOW THE FOCUS WILL BE ON WRN MA AND SRN
NH WHERE CONFIDENCE IS HIGHER AND DOWNSLOPING MAY ASSIST WITH
MIXING THE BL...BUT MAY NEED TO MONITOR FOR POSSIBLE EXPANSION S
AND E SHOULD THE CORE OF THIS SPEED MAX SHIFT SOMEWHAT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
TONIGHT...
WINDS RAPIDLY DIE OFF OVER LAND TONIGHT THANKS TO A COMBINATION OF
LACK OF MIXING AFTER SUNSET AND GRADUAL CREST OF HIGH PRES TO THE
S. THIS RIDGE WILL ALLOW SKIES TO BE MAINLY CLEAR THROUGH THE
OVERNIGHT HOURS AND THE WEAK FLOW WILL LEAD TO DECENT SETUP FOR
RADIATIONAL COOLING ACROSS THE REGION AWAY FROM THE COAST.
THEREFORE...EXPECT MINS TO FALL BACK INTO THE 20S AND LOW 30S.
MONDAY...
SFC HIGH PRES WILL MOVE OFFSHORE AS MID LVL RIDGING CRESTS OVER
THE REGION DURING THE DAYLIGHT HOURS THEREFORE...EXPECTING A
MAINLY DRY DAY AS THE HIGH SHOULD PREVENT PRECIP IN ADVANCE OF A
SECONDARY COLD FRONT TO THE W FROM AFFECTING THE REGION UNTIL THE
OVERNIGHT HOURS. LITTLE CHANGE IN THE AIRMASS IN PLACE AND ANOTHER
ROUND OF DECENT MIXING SUGGESTS MAX TEMPS WILL BE CLOSE TO IF NOT
SLIGHTLY WARMER THAN SUNDAY ALBEIT WITH WEAKER SW FLOW.
THEREFORE...HAVE HIGHS IN THE LOW 40S TO AROUND 50 DESPITE A SLOW
INCREASE IN AFTERNOON AND EVENING CLOUD COVER IN ADVANCE OF THE
INCOMING WAVE.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...
* ABOVE NORMAL TEMPERATURES THROUGH FRIDAY
* RAIN LIKELY TUE...ESPECIALLY NEAR THE COAST THEN RAIN/SNOW SHOWERS
POSSIBLE WED/WED NIGHT
* COLDER NEXT WEEKEND WITH BELOW NORMAL TEMPS
OVERVIEW...
MEDIUM RANGE GUIDANCE IN REASONABLY GOOD AGREEMENT ON AMPLIFYING
PATTERN NEXT WEEK WITH MAIN FEATURES BEING A BUILDING RIDGE ACROSS
THE WESTERN CONUS AND A MEAN TROF OVER THE LAKES. A SERIES OF
FRONTAL WAVES WILL DEVELOP AND MOVE THROUGH THE NE...BUT THERE ARE
DIFFERENCES IN THE TRACK AND STRENGTH OF THESE WAVES WHICH AFFECT
SENSIBLE WEATHER. GENERALLY ABOVE NORMAL TEMPS EXPECTED THROUGH THE
END OF THE WEEK. THERE WILL BE TWO MAIN THREATS OF PRECIP...LATE
MON NIGHT AND TUE AND AGAIN LATE WED/WED NIGHT BUT THERE ARE
DIFFERENCES IN THE GUIDANCE. INTERNATIONAL MODEL SUITE IS CLOSER TO
THE COAST WITH THE FRONTAL WAVE AND WETTER THAN US MODELS FOR TUE
AND WE LEANED TOWARD WETTER SOLUTION. MEANWHILE GFS IS MORE ROBUST
THAN ECMWF AND ITS ENSEMBLES WITH A WAVE MOVING INTO NEW ENG WED
NIGHT WITH A LIGHT INTERIOR SNOWFALL AS A MORE AMPLIFIED TROF
APPROACHES...BUT ECMWF SHOWING JUST A FROPA. THESE FRONTAL WAVES AT
LONGER TIME RANGES OFFER LOW PREDICTABILITY SO CONFIDENCE IS BELOW
AVERAGE. THE MAIN LONGWAVE TROF AXIS EVENTUALLY MOVES EAST INTO NEW
ENG FOR THE WEEKEND WHICH WILL BRING COLDER TEMPS.
DAILIES...
MON NIGHT INTO TUE...
APPROACHING COLD FRONT WILL BRING INCREASING CHC SHOWERS TO INTERIOR
MON NIGHT...THEN WE TRENDED FORECAST TOWARD WETTER ECMWF SOLUTION
WITH DEVELOPING FRONTAL WAVE ON THE BAROCLINIC ZONE BRINGING A
PERIOD OF RAIN...ESPECIALLY TUE AFTERNOON INTO THE EARLY EVENING IN
THE COASTAL PLAIN. POPS WERE INCREASED TO LIKELY NEAR THE COAST.
UKMET RATHER BULLISH ON RAINFALL WITH UP TO AN INCH NEAR THE COAST
AND ECMWF WHILE LIGHTER ALSO HAS DECENT SLUG OF QPF.
HOWEVER...FORECAST CONFIDENCE IS BELOW AVERAGE AND NOTE THAT GFS/NAM
ARE MAINLY DRY TUE AFTERNOON. ANOTHER MILD DAY WITH TEMPS WELL
ABOVE NORMAL.
WED INTO WED NIGHT...
NEXT MORE AMPLIFIED TROF APPROACHES FROM THE WEST WITH A COLD FRONT
MOVING INTO THE REGION LATE WED/WED NIGHT. THIS SHOULD BRING
RAIN/SNOW SHOWERS...BUT LOW CONFIDENCE ON POTENTIAL FOR A COASTAL
WAVE BRINGING A MORE ORGANIZED SNOWFALL TO THE INTERIOR PER GFS.
THURSDAY...
LOOKS MAINLY DRY AS RIDGING DEVELOPS BEHIND DEPARTING WAVE...WITH
OCEAN LOW DEVELOPMENT ASSOCD WITH SOUTHERN PART OF THE TROF REMAINING
FAR ENOUGH OFFSHORE. COOLER TEMPS IN POST FRONTAL AIRMASS...BUT
JUST CLOSER TO SEASONABLE NORMALS.
FRIDAY AND SATURDAY... SOMEWHAT MILDER TEMPS MOVE BACK IN FRI AHEAD
OF THE MAIN TROF AND COLD FRONT...THEN COLDER TEMPS TRENDING BELOW
NORMAL FOR NEXT WEEKEND. CHC SNOW SHOWERS FRI NIGHT AND SAT AS TROF
AXIS MOVES INTO NEW ENG...AND WILL HAVE TO WATCH FOR A POSSIBLE WAVE
DEVELOPING JUST OFFSHORE ON THE FRONT FOR SAT.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH MONDAY/...
HIGH CONFIDENCE IN TRENDS...LOWER CONFIDENCE IN TIMING THIS
MORNING.
THROUGH 12Z...
GRADUALLY IMPROVEMENT TO VFR EVERYWHERE AS THE
COLD FRONT MOVES THROUGH THE ERN TERMINALS IN THE NEXT COUPLE OF
HOURS. WINDS WILL BE SHIFTING FROM MOSTLY SSW TO WSW AS THE FRONT
MOVES THROUGH. ONCE THE WINDS SHIFT VFR IS EXPECTED EVERYWHERE.
OTHERWISE...
VFR DOMINATES THROUGH MONDAY. MAIN CONCERN WILL BE THE THREAT FOR
WSW WIND GUSTS AROUND 40 KT DURING THE DAYLIGHT HOURS TODAY. THIS
WILL BE A THREAT OVER NEARLY ALL TERMINALS...BUT TERMINALS AT
HIGHER ELEVATIONS WILL HAVE A SLIGHTLY BETTER CHANCE. THE WINDS
SHOULD DROP OFF OVERNIGHT AND INCREASE AGAIN A BIT MONDAY...BUT
NOT AS STRONG.
KBOS TAF...HIGH CONFIDENCE IN TRENDS. LOWER CONFIDENCE IN EXACT
TIMING OF STRONGER WIND GUSTS AFTER SUNRISE.
KBDL TAF...HIGH CONFIDENCE IN TRENDS. LOWER CONFIDENCE IN EXACT
TIMING OF STRONGER WIND GUSTS AFTER SUNRISE.
OUTLOOK...MONDAY NIGHT THROUGH THURSDAY...
MON NIGHT INTO TUE...MODERATE CONFIDENCE. LOWERING TO MVFR/IFR AS
SHOWERS MOVE INTO THE REGION FROM THE WEST MON NIGHT...WITH MAIN
FOCUS FOR RAIN ON TUESDAY IN THE COASTAL PLAIN.
WED...LOW CONFIDENCE. CONDITIONS MAY LOWER TO MVFR/IFR IN ANOTHER
PERIOD OF RA/SNOW SHOWERS WED INTO WED NIGHT.
THU...MODERATE CONFIDENCE. VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
NEAR TERM /THROUGH MONDAY/...HIGH CONFIDENCE.
TODAY INTO EARLY MONDAY...
W GALE FORCE WINDS /TO AROUND 40 KT IN SPOTS/ ARE EXPECTED THROUGH
THE DAY TODAY WHICH WILL GIVE WAY TO 25-30 KT WINDS THIS EVENING
AND FINALLY SUB 25 KT WINDS BY EARLY MONDAY MORNING. THEREFORE
GALE WARNINGS PREVAIL THROUGH THE DAY TODAY WHICH WILL GIVE WAY
TO SMALL CRAFT ADVISORIES OVERNIGHT. THE SMALL CRAFTS ARE LIKELY
TO STAY UP INTO THE MID DAY HOURS MONDAY AS SEAS WILL TAKE SOME
TIME TO DROP BELOW 5 FT ON THE OCEAN WATERS ESPECIALLY.
LATE MONDAY...
ALTHOUGH WINDS WILL SHIFT TO THE SW AND DROP OFF FOR MUCH OF THE
DAY...SEAS MAY HOLD AT OR ABOVE 5 FT ON OCEAN WATERS. SOME SMALL
CRAFTS MAY CONTINUE.
OUTLOOK...MONDAY NIGHT THROUGH THURSDAY...
MON NIGHT INTO TUE...A PERIOD OF SCA SW WINDS LIKELY MON NIGHT
ASSOCD WITH A LOW LEVEL JET...THEN DIMINISHING WIND TUE. BUT LOW
CONFIDENCE ON POTENTIAL FOR STRONGER WINDS DEVELOPING OVER EASTERN
WATERS WITH LOW PRES. VSBYS OCCASIONALLY REDUCED IN RAIN AND
FOG...ESPECIALLY ON TUE.
WED...MODERATE CONFIDENCE. SW WINDS MAINLY BELOW SCA...SHIFTING TO
W/NW WED NIGHT.
THU...MODERATE CONFIDENCE. WINDS BELOW SCA THU...BUT INCREASING SW
FLOW THU NIGHT AHEAD OF A COLD FRONT.
&&
.HYDROLOGY...
* FLOOD WATCHES REMAIN IN PLACE FOR NORTHERN CT...WESTERN MA AND
SRN NH.
BULK OF THE RAIN HAS ENDED SAVE FOR A FEW SHOWERS OVER ERN MA/RI
WHICH WILL BE OFFSHORE BY AROUND 7 AM. OVERALL RAINFALL TOTALS
WERE GENERALLY CLOSE TO IF NOT SLIGHTLY BELOW THE PROJECTED
AMOUNTS WITH IN THE WATCH AND A BIT HIGHER IN ERN MA AND RI.
HOWEVER...ICE IS NOT AS MUCH OF AN ISSUE WHERE THE HEAVIER RAIN
FELL.
DESPITE THE FACT THAT RAIN TOTALS WERE NOT AS HIGH IS THEY MIGHT
HAVE BEEN...WE CONTINUE TO NOTE RAPID RISES OF SEVERAL STREAMS IN
WRN MA/NH PARTICULARLY THOSE WHICH WERE KNOWN TO BE ICE COVERED.
THEREFORE...SINCE TEMPERATURES ARE GENERALLY EXPECTED TO REMAIN
ABOVE FREEZING THROUGH THE DAY TODAY...MORE ICE MOVEMENT IS
POSSIBLE WHICH COULD TRIGGER DAMMING AND RAPID RISES UNTIL THE NEW
RAINFALL IS FLUSHED OUT. THEREFORE...WILL MAINTAIN THE CURRENT
WATCH AND ITS TIMING THROUGH THIS EVENING DUE TO THE CONTINUED
THREAT. IF...BY LATE THIS EVENING NOT MUCH MOVEMENT OR DAMMING IS
OBSERVED...THE LACK OF RAINFALL FOR ABOUT 12 HOURS...AND THE FACT
THAT TEMPERATURES WILL DROP BACK TO FREEZING AGAIN TONIGHT SHOULD
MITIGATE FURTHER RISK.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH THROUGH THIS AFTERNOON FOR CTZ002>004.
MA...FLOOD WATCH THROUGH THIS AFTERNOON FOR MAZ002>004-008>012-026.
WIND ADVISORY FROM 7 AM THIS MORNING TO 7 PM EST THIS EVENING
FOR MAZ002>004-008>012-026.
NH...FLOOD WATCH THROUGH THIS AFTERNOON FOR NHZ011-012-015.
WIND ADVISORY FROM 7 AM THIS MORNING TO 7 PM EST THIS EVENING
FOR NHZ011-012-015.
RI...NONE.
MARINE...GALE WARNING FROM 10 AM THIS MORNING TO 7 PM EST THIS EVENING
FOR ANZ231>234.
GALE WARNING FROM 7 AM THIS MORNING TO 7 PM EST THIS EVENING
FOR ANZ230-235>237.
GALE WARNING FROM 7 AM THIS MORNING TO 10 PM EST THIS EVENING
FOR ANZ250-251-254>256.
&&
$$
SYNOPSIS...KJC/DOODY
NEAR TERM...DOODY
SHORT TERM...DOODY
LONG TERM...KJC
AVIATION...KJC/DOODY
MARINE...KJC/DOODY
HYDROLOGY...STAFF
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
620 PM EST MON JAN 13 2014
.SYNOPSIS...
A COLD FRONTAL BOUNDARY LOCATED FROM THE GULF COAST STATES TO THE
GREAT LAKES WILL MOVE EAST TONIGHT. LOW PRESSURE WILL DEVELOP ALONG
THIS FRONT IN THE SOUTHEASTERN UNITED STATES MOVING INTO THE
MID-ATLANTIC REGION BY TUESDAY ACCOMPANYING THE COLD FRONT. ANOTHER
COLD FRONTAL BOUNDARY WILL PASS THROUGH THE REGION ON WEDNESDAY. WITH
LOW PRESSURE DEVELOPING OFFSHORE WEDNESDAY NIGHT AND THURSDAY.
ANOTHER FRONTAL BOUNDARY AND LOW PRESSURE SYSTEM WILL APPROACH THE
REGION FOR THE FRIDAY NIGHT AND SATURDAY TIME PERIOD.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
TEMPERATURES THIS EVENING WILL START OFF FAIRLY MILD AND DIURNAL
RANGE FOR TONIGHT WILL BE TRIMMED BASED ON INCREASING CLOUD COVER.
RAISED TEMPERATURES FOR TONIGHTS LOW BY SEVERAL DEGREES, USING
BLEND OF MAV AND RUC GUIDANCE.
PREVIOUS FORECAST TIMING FOR PRECIPITATION ONSET STILL LOOKS GOOD
AND WAS LEFT UNCHANGED. DID UPDATE WITH LATEST WPC QPF GUIDANCE.
RAINFALL AMOUNTS ARE RELATIVELY LIGHT. GIVEN MILD OVERNIGHT
TEMPERATURES, PRECIPITATION FORECAST CONTINUES ALL LIQUID. DID NOT
MAKE ANY SIG CHANGES TO THE FCST WITH THIS UPDATE. LATEST GUID
STILL LOOKS GOOD FOR PRECIP ONSET TIME. WILL RE-EXAMINE FOR LATE
EVE UPDATE.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
A WET START TO THE DAY THOUGH AMOUNTS STILL LOOKS TO BE RELATIVELY
LIGHT. TOTAL QPF AMOUNTS EXPECTED TO BE UNDER A HALF INCH.
PRECIPITATION WILL BE OVER WITH PRIOR TO THE END OF THIS TIME
PERIOD.
BETWEEN CLOUD COVER EARLY AND COLD AIR ADVECTION LATER IN THE DAY,
DAYTIME HIGH TEMPERATURES WILL RUN ONLY 8 TO 10 DEGREES OVER
PREVIOUS NIGHT MINIMUM. THAT BEING SAID, STILL QUITE MILD
TEMPERATURES FOR MID-JANUARY.
USED MET/MAV BLEND FOR DAYTIME HIGH TEMPERATURES.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
TUESDAY NIGHT: SHOULD SEE A GRADUAL REDUCTION IN CLOUDS WITH A BRIEF
BREAK BEFORE THE NEXT SYSTEM MOVES INTO THE REGION. WESTERLY FLOW
MAY TURN QUICKLY TO SOUTHERLY FLOW BY MORNING WITH 850 MB TEMPS ONLY
FALLING TO AROUND 0C. DO NOT EXPECT MUCH OF A TEMPERATURE DROP.
FAIRLY TIGHT CLUSTER WITH REGARDS TO MODELS IN THIS PERIOD WITH MOST
ELEMENTS.
WEDNESDAY: THE NEXT FRONTAL BOUNDARY SHOULD BE QUICKLY MOVING INTO
THE REGION BY WEDNESDAY AFTERNOON WITH WAA AHEAD OF THE BOUNDARY. A
WEAK DISTURBANCE MAY RESULT IN SOME SCATTERED SHOWERS, MAINLY IN THE
FORM OF RAIN AHEAD OF THE FRONT TEMPERATURES MAY WARM WELL INTO THE
40`S. IN FACT THE TIMING OF THIS SYSTEM LOOKS SLOWER WHICH KEEPS US
ON THE WARM SIDE LONGER RESULTING IN A WARMING TREND FROM PREVIOUS
FORECASTS IN THIS PERIOD. DID NOT GO AS HIGH AS THE 12Z MEX- 51 AT
PHL BUT DID RAISE TEMPS. QPF SHOULD BE FAIRLY LIGHT WITH THE LACK OF
DEEP MOISTURE PRESENT MAINLY USED A 09Z SREF/ 12Z MOS BLEND FOR POPS
AND WENT A LITTLE WETTER THAN THE 09Z SREF FOR QPF.
WEDNESDAY NIGHT AND THURSDAY: THE PATTERN SHOULD BECOME MORE AMPLIFIED
DURING THIS TIME PERIOD. A TREND THAT STARTED WITH YESTERDAY`S 12Z
ECMWF. STRONGER DISTURBANCES MARKED WITH INCREASED 500 MB VORTICITY
ARE LIKELY TO ROUND THE BEND IN THE AMPLIFYING TROUGH ALLOWING FOR
POTENTIAL LOW PRESSURE DEVELOPMENT. THE QUESTION IS DO THEY TRACK
CLOSE ENOUGH TO THE COAST TO IMPACT OUR WEATHER? WELL IT LOOKS TO BE
A CLOSE MISS AT THIS POINT WITH POTENTIAL FOR SOME ORGANIZATION OF
A LOW PRESSURE SYSTEM OFF THE CAROLINA COAST MOVING OUT TO SEA. THE
OVERALL PROGRESSIVE NATURE OF THE PATTERN WOULD ALSO SUPPORT THIS. A
CHANCE FOR RAIN AND SNOW WOULD OCCUR FOR THE SOUTHERN AND COASTAL
SECTIONS OF THE REGION AS CAA MOVES INTO THE REGION WITH THE
NORTHERN/ WESTERN REGIONS DRY.
A FEATURE OF NOTE WHICH SHOWED UP ON BOTH THE ECMWF AND CMC 12Z
RUNS WAS AN INVERTED TROUGH WHICH COULD ENHANCE PRECIPITATION
ACROSS OUR AREA THURSDAY EVEN WITH A FURTHER OFFSHORE TRACK. WILL
NEED TO SEE THE MODELS BECOME STEADY WITH THIS FEATURE BEFORE
BUYING INTO IT. SIMILAR METHODS WITH POPS AND QPF AS WITH THE
WEDNESDAY PERIOD. A SLOWER MOVING TROUGH OR A STRONGER DISTURBANCE
COULD PULL ANY POTENTIAL LOW PRESSURE SYSTEM CLOSER TO THE COAST
AND THIS WILL BE WATCHED. HOWEVER THAT POSSIBILITY HAS LITTLE
ENSEMBLE SUPPORT FROM BOTH THE ECMWF ENSEMBLE MEAN AND THE GFS
ENSEMBLE SUITE AT THIS POINT. THIS SUPPORT HAS INCREASED ON THE
RECENT GFS ENSEMBLE PACKAGE. TEMPERATURES WILL BE DEPENDENT ON
PRECIPITATION AND CLOUD COVER DID UNDERCUT MOS GUIDANCE IN THE
THURSDAY PERIOD GIVEN THE POTENTIAL FOR CLOUDS, PRECIPITATION AND
CAA.
THURSDAY NIGHT AND FRIDAY: A BREAK AHEAD OF THE NEXT SYSTEM IS
LIKELY ON FRIDAY WITH A RETURN TO SOUTHERLY FLOW AND SUNSHINE. THINK
THE 12Z GFS IS JUST A BIT TO QUICK BRINGING IN THE NEXT SYSTEM AND
WENT WITH A DRY FORECAST. TOOK A MIDDLE GROUND BUT CLOSER TO THE ECMWF WITH
REGARDS TO TEMPERATURES.
FRIDAY NIGHT THROUGH SATURDAY NIGHT: THE ECMWF BRINGS A CLIPPER
SYSTEM FURTHER NORTH PHASING IT INTO A LOW PRESSURE SYSTEM FROM THE
SOUTHERN BRANCH LEADING TO A DECENT RAIN/SNOW EVENT. WHILE THE GFS
IS COOLER AND WEAKER ONLY BRINGING SCATTERED FLURRIES. ONLY A FEW
MEMBERS OF THE ENSEMBLE SUITE SHOWING SOMETHING MORE THAN A CLIPPER.
THE UKMET AND CMC ALSO HAVE THERE OWN IDEAS. DID NOT BUY INTO THE OP
ECMWF WAA SURGE AHEAD OF THIS SYSTEM AND KEPT TEMPERATURES MORE
ALONG THE LINES OF THE MEX AND 12Z GFS. FOR NOW ONLY BROUGHT UP POPS
INTO THE LOW CHANCE RANGE GIVEN THE HIGHER DEGREE OF UNCERTAINTY IN
THIS PERIOD.
SUNDAY AND MONDAY: FAIRLY GOOD AGREEMENT ON MOST WEATHER ELEMENTS IN
THIS PERIOD WITH THE MODEL GUIDANCE AND STUCK FAIRLY CLOSE TO WPC. A
PERIOD OF CAA ON THE BACKSIDE OF ANY FRONT OR STORM SYSTEM WITH 850
MB TEMPS FALLING BELOW -10C WE MAY STRUGGLE TO REACH FREEZING FROM
PHL NW. COUPLED WITH SOME WIND IT SHOULD BE A FAIRLY COLD DAY
SUNDAY. WE SHOULD MODERATE MONDAY AHEAD OF THE NEXT FRONTAL SYSTEM.
GENERAL OUTLOOK: THE STAIR STEP DOWN TO NEAR SEASONAL AND THEN BELOW
SEASONAL TEMPERATURES WILL OCCUR AS A SERIES OF COLD FRONTS MOVE
THROUGH THE REGION. OUR OLD FRIEND, THE POLAR VORTEX CURRENTLY IN
NORTHWESTERN CANADA IS ABOUT TO TAKE A HIT. AN UPWARD PROPAGATING
ROSSBY WAVE IS PREDICTED TO PERTURB AND ELONGATE IT DURING THE
LONG TERM PERIOD (AND BEYOND). THIS SHOULD ONCE AGAIN SEND PART OF
THE VORTEX INTO NORTHEASTERN CANADA. COUPLED WITH DISTURBANCES
CRESTING THE EASTERN PACIFIC RIDGE, THEY WILL ACT IN TANDEM TO
BRING COLDER AIR INTO THE FORECAST AREA ONCE AGAIN. THE LATEST
ECMWF STRATOSPHERIC MODEL SOLUTION POLAR VORTEX HIT IS SO INTENSE,
THIS IS THE FIRST TIME THIS WINTER THAT STRATOSPHERIC WARMING
(STRONGER AROUND 10MB FOR NOW) IS PREDICTED TO START. WHETHER IT
CAN WORK ITS WAY DOWN INTO THE TROPOSPHERE AND WHERE IT DOES,
WOULD HAVE AN IMPACT ON THE NORTHERN HEMISPHERE`S WEATHER AND
TELECONNECTION PATTERNS INTO FEBRUARY.
BEYOND OUR DETERMINISTIC PERIOD THE WEEK2 TEMPS: THE LINES
CONTINUE TO BE DRAWN BETWEEN THE NAEFS (NEAR NORMAL) AND THE ECMWF
(DONT ASK). BOTH HAVE BEEN REMAINING IN THEIR RESPECTIVE NORMAL VS
COLD CAMPS. HOWEVER BOTH THE GFS AND ECMWF OP RUNS FROM THIS
AFTERNOON ARE SHOWING OMINOUS SIGNS THE ARCTIC AIR IS RETURNING
TO THE PATTERN.
&&
.AVIATION /23Z MONDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TONIGHT...VFR WILL CONTINUE FOR THE FIRST PART OF THE NIGHT WITH
LOWERING AND THICKENING CLOUDS. FOR THE SECOND HALF OF THE NIGHT
EXPECT MVFR AND PSBL IFR TO DEVELOP ALG WITH SOME SHWRS. S TO SW
WINDS ARE EXPECTED TO BE LESS THAN 10 KTS, BUT MAY STAY IN THE
7-10 KT RANGE ERLY.
TUESDAY...MVFR TO IFR CONDITIONS EXPECTED WITH RAIN. IMPROVEMENT
DURING THE AFTERNOON.
OUTLOOK...
TUESDAY NIGHT: CONTINUED IMPROVING TO VFR WITH DECREASING CLOUDS
WEDNESDAY THROUGH THURSDAY: MAINLY VFR, SOME RESTRICTIONS TO MVFR IN
ANY RAIN OR SNOW SHOWERS.
FRIDAY: VFR
SATURDAY: LOCAL RESTRICTIONS TO MVFR IN RAIN AND SNOW SHOWERS.
&&
.MARINE...
SMALL CRAFT ADVISORY CONTINUES IN PLACE FOR TONIGHT ON ATLANTIC
WATERS AND HAS BEEN EXTENDED THROUGH THE DAY THURSDAY BASED ON
EXPECTED CONTINUED SEAS OF 5 FEET.
A SOUTHERLY FLOW WILL INCREASE TONIGHT AHEAD OF AN APPROACHING COLD
FRONT. THE WINDS LOOK MARGINAL REGARDING A SMALL CRAFT ADVISORY, AS
GUSTS WILL APPROACH 25 KNOTS ON THE OCEAN, HOWEVER, THE INCREASING
SOUTHERLY FLOW WILL ALLOW THE SEAS TO BUILD TONIGHT. SEAS ARE
EXPECTED TO BUILD TO 5 FEET IN SOUTHERLY FLOW THIS EVENING AND
CONTINUE OVERNIGHT AND INTO THE DAY TUESDAY. THOUGH WINDS WILL DROP
OFF DURING THE DAY TUESDAY, SEAS ARE EXPECTED TO REMAIN HIGH ENOUGH
TO WARRANT A SMALL CRAFT ADVISORY THROUGH THE DAYTIME HOURS
TUESDAY.
NO SMALL CRAFT ADVISORY ON THE DELAWARE BAY AS SEAS ARE NOT
EXPECTED TO GET TO 5 FEET AND WINDS SHOULD GENERALLY REMAIN BELOW 25
KNOTS. AS A COLD FRONT ARRIVES LATE TONIGHT, SOME RAIN IS EXPECTED
TO MOVE IN MAINLY TOWARD DAYBREAK. THERE DOES NOT APPEAR TO BE A
SIGNIFICANT SURGE IN THE DEW POINTS TONIGHT, THEREFORE FOG IS NOT
ANTICIPATED TO BECOME A CONCERN.
OUTLOOK...
TUESDAY NIGHT...A LIKELY PERIOD OF SUB SMALL CRAFT ADVISORY
CONDITIONS. SEAS MIGHT REMAIN CLOSE ON THE OCEAN.
WEDNESDAY AND WEDNESDAY NIGHT...ANOTHER RAMP UP INTO POSSIBLE SMALL
CRAFT ADVISORY CRITERIA IN THE SOUTHWEST FLOW PRECEDING THE NEXT
COLD FRONT. GREATER CONFIDENCE ON THE OCEAN THAN DELAWARE BAY.
THURSDAY THROUGH FRIDAY...A GENERAL SOUTHWEST FLOW IS PREDICTED
PRECEDING THE NEXT COLD FRONT. WE MIGHT COME CLOSE TO MEETING SMALL
CRAFT ADVISORY CRITERIA AGAIN, WITH HIGHER CONFIDENCE ON THE OCEAN
AND ON FRIDAY AS THE COLD FRONT COMES CLOSER BY FRIDAY.
SATURDAY: SCA CONDITIONS LIKELY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST TUESDAY FOR ANZ450>455.
&&
$$
SYNOPSIS...GAINES
NEAR TERM...SZATKOWSKI/NIERENBERG
SHORT TERM...SZATKOWSKI
LONG TERM...GAINES/GIGI
AVIATION...GAINES/SZATKOWSKI/NIERENBERG
MARINE...GAINES/GIGI/SZATKOWSKI
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
931 AM EST SUN JAN 12 2014
.SYNOPSIS...
A LARGE AREA OF LOW PRESSURE OVER EASTERN CANADA WILL MOVE INTO THE
ATLANTIC TODAY. HIGH PRESSURE WILL BUILD ACROSS THE REGION TONIGHT
THROUGH MONDAY...BUT THEN MOVE AWAY FROM THE AREA. LOW PRESSURE WILL
MOVE ACROSS THE GREAT LAKES TUESDAY SENDING A FRONT ACROSS THE AREA
TUESDAY. ANOTHER WAVE OF LOW PRESSURE WILL AFFECT THE AREA TUESDAY
NIGHT FOLLOWED BY A COLD FRONT LATER WEDNESDAY. HIGH PRESSURE WILL
BUILD IN FOR THURSDAY...FOLLOWED BY ANOTHER LOW PRESSURE AREA FOR
EARLY NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ADJUSTED CLOUD COVER UP A BIT MORE AND FOR A LITTLE LONGER THROUGH
THE MORNING HOURS. LATEST RUC IS SHOWING A LOT OF STUBBORN
MOISTURE AT 925MB HANGING AROUND THROUGH MUCH OF THE DAY BUT DID
NOT GO THAT PESSIMISTIC AS WE SHOULD START TO SEE BETTER BUILDING
HEIGHTS AND MORE SUBSIDENCE TAKING PLACE. SHOULD START TO SEE MORE
BREAKS IN THE STRATOCU DECK BY LATE MORNING WITH MORE DOWNSLOPING
AND THE HIGHER SUNANGLE.
OTHERWISE, BOTH THE GFS AND WRF-NMMB INITIALIZATION LOOKED GOOD
AT 500MB, AT 850MB AND 925MB THEY WERE ADVECTING IN THE COLD AIR
TOO QUICKLY AND THEIR BIAS OF THE CORE OVER THE LOWER LAKES WAS
AROUND 1C TOO COLD.
WITH NO MEASURABLE PCPN TO SPEAK ABOUT, THE HIGHER CONCERN IS ON
TEMPS. WE LEANED TOWARD THE HIGHER STAT GUIDANCE BECAUSE OF THE SAID
BIAS AND ALSO OUR CURRENT RELATIVE WARMTH. ANOTHER WINTER DAY IN
WHICH OUR CALENDAR DAY HIGH LIKELY ALREADY OCCURRED AT 1201 AM. THIS
IS A QUICK SHOT OF "COOLER AIR" AS THE THERMAL TROF PASSES THROUGH
THIS MORNING. IT WILL BE A BRISK DAY AS THERE STILL WILL BE 25 TO 30
KTS OF WIND FORECAST AT 925 MB INTO THIS AFTERNOON. MOST OF IT
SHOULD MIX DOWN EASIER THAN YESTERDAY (NOT COMPLAINING AS THE WINDS
AT 925MB WERE TWICE AS STRONG YESTERDAY). WE HAVE PEAK GUSTS CLOSE
TO 30 MPH IN MOST OF THE AREA. LASTLY ABOUT CLOUDS, THE GFS IS
FORECASTING A LOWER CONVECTIVE TEMP THAN THE WRF-NMMB. BOTH THE
ECMWF AND CAN RGEM LOOK CLOSER TO THE GFS. SO WE DID NOT GO
COMPLETELY SUNNY. STILL PLENTY OF STRATOCU TO OUR WEST. AS IS
TYPICALLY THE CASE, THE CONVECTIVE TEMP GETS EASILY REACHED FAR
NORTH, JUST GETS REACHED ALONG I95 AND NOT AT ALL IN DELMARVA. WE
TRIED TO REFLECT THIS IN THE GRIDS. BECAUSE OF SOME LAKE EFFECT
ECHOES IN WESTERN PA (THE FLOW LOOKS MORE WNW THAN WE EXPECTED
YESTERDAY), WE DID KEEP THE CHANCE OF MORNING FLURRIES IN THE
POCONOS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
A RADIATIONAL COOLING NIGHT IS FORECAST FOR MOST OF TONIGHT. BOUNDARY LAYER
WINDS START WEAK ENOUGH TO PERMIT DECOUPLING IN THE EVENING. THEY DO
INCREASE TOWARD MORNING, WE HAVE MINS OCCURRING SLIGHTLY EARLIER
THAN USUAL. THE WRF-NMMB MORE THAN THE GFS BRINGS CIRRUS NORTH AFTER
MIDNIGHT. EVEN WITH THIS GIVEN MOST OF THE NIGHT SHOULD BE CLEAR, WE
ARE NOT EXPECTING THE CLOUDS TO HAVE AN IMPACT ON THE FINAL MINS.
WE LEANED CLOSER TO THE LOWER STAT GUIDANCE IN NON-URBAN/NON-COASTAL
AREAS FOR MIN TEMPS.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
MONDAY WILL PROBABLY HAVE THE BEST WEATHER OF THE UPCOMING WEEK. IT
IS EXPECTED TO BE DRY AS A RIDGE OF HIGH PRESSURE WILL BE ACROSS THE
AREA. THE AIRMASS IN PLACE IS NOT COLD...SO HIGH TEMPERATURES WILL
BE ABOVE NORMAL. HIGHS SHOULD RANGE FROM THE UPPER 40S/LOW 50S
ACROSS THE NORTH TO THE MID 50S OVER THE DELMARVA.
SEVERAL AREAS OF LOW PRESSURE WILL MOVE TOWARDS THE EAST COAST
TUESDAY AND WEDNESDAY. ONE WILL BE MOVING ACROSS THE SOUTHEAST U.S.
AND THIS SYSTEM WILL BRING MOISTURE TO THE AREA MONDAY NIGHT INTO
TUESDAY. THE TEMPERATURES WILL STILL BE WARM ENOUGH FOR MOSTLY RAIN
ACROSS THE AREA. WE HAVE USED THE WPC POPS AND ADJUSTED THEM TO FIT
THE NEARBY OFFICES...SO POPS ARE MOSTLY IN THE HIGH CHC/LOW LIKELY
RANGE. THE LOW WILL MOVE OFF THE COAST TUESDAY NIGHT WHILE A SECOND
LOW MOVES ACROSS THE GREAT LAKES. THIS SECOND LOW WILL USHER IN
COLDER AIR BEHIND IT FOR THE MIDDLE OF THE WEEK. PCPN WILL MOSTLY BE
RAIN WEDNESDAY...BUT THEN CHANGE TO SNOW WED EVENING BEFORE ENDING.
POPS ARE IN THE CHC RANGE AT THIS TIME. SINCE THE SYSTEM WILL BE
MOVING RATHER QUICKLY...ANY SNOW AMTS WILL BE LIGHT. LOWS WILL DROP
INTO THE 20S WED NIGHT.
THE REST OF THE EXTENDED PERIOD WILL FEATURE DRY WEATHER AND
TEMPERATURES WHICH WILL BE NORMAL OR ABOVE (THU/FRI) AND THEN BELOW
NORMAL FOR SAT. A COLD FRONT WILL CROSS THE AREA FRI NIGHT. THE
LATEST EC MODEL IS SHOWING THE POSSIBILITY FOR SOME PCPN FRI NIGHT
AND SAT...BUT CONFID IN ANY MODEL SOLUTION THAT FAR OUT IS LOW ATTM
AND WE WILL STICK WITH THE DRY FCST OFFERED BY WPC.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THE 12Z TAFS ARE VFR THRUT.
THIS MORNING, NORTHWEST WINDS SHOULD INCREASE AND AVERAGE CLOSE TO
15 KTS WITH GUSTS BETWEEN 20 AND 30 KTS BY THE END OF THE MORNING.
THIS WILL CONTINUE INTO THE AFTERNOON. CLOUDS: WE CARRY A VFR
STRATOCU CIG FOR MOST OF OUR TERMINALS THROUGH THE MORNING HOURS
BEFORE SCATTERING THEM OUT. THIS AFTERNOON WE ARE EXPECTING
FEW/SCATTERED CU/SC. MOST COVERAGE AND POSSIBLE VFR CIGS AT KABE
AND KRDG.
SUNDAY EVENING AND INTO THE OVERNIGHT. WINDS WILL DECREASE
RAPIDLY AND ANY LEFTOVER CU OR SC CLOUDS WILL DISSIPATE. BY THE
MIDDLE/LATE EVENING MOST TERMINALS WILL HAVE LIGHT AND VARIABLE
WINDS. EXCEPTION IS KPHL WHERE WE BACKED THE (STILL LIGHTER) WINDS
TO THE SOUTHWEST.
ON MONDAY MORNING WE START KPHL WITH A SOUTHSOUTHWEST WIND AND THE
ARRIVAL OF SOME CIRRUS.
OUTLOOK...
MONDAY...VFR EXPECTED.
MON NIGHT THRU WED...MOSTLY MVFR WITH BRIEF IFR POSSIBLE IN
SHOWERS.
WED NIGHT/THU...MOSTLY VFR. SNOW SHOWERS POSSIBLE NORTH.
&&
.MARINE...
WHILE THERE IS COLD AIR ADVECTION TODAY, THE AIR MASS IS NOT A
PARTICULARLY COLD ONE. THIS IS INDICATED IN THE FORECAST SOUNDINGS
THAT EVEN OVER THE OCEAN ARE NOT MIXING COMPLETELY AOB 900MB. WE
WILL CONTINUE WITH THE SCA FOR ALL OF OUR WATERS FOR TODAY. AS THE
AFTERNOON PROGRESSES CONFIDENCE ABOUT SMALL CRAFT ADVISORY CRITERIA
WINDS CONTINUING ON DELAWARE BAY LESSEN.
FOR TONIGHT, WE WILL START DELAWARE BAY BELOW SMALL CRAFT ADVISORY
CRITERIA. THE EVENING SMALL CRAFT ADVISORY FOR THE OCEAN IS MORE FOR
THE SEAS THAN WINDS AS WAVE WATCH GUIDANCE HAS BEEN CONSISTENT IN
NEEDING THIS MUCH TIME FOR THE SERLY SWELLS TO SUBSIDE.
OUTLOOK...
MON/TUE...WINDS SEAS BUILDING WITH SCA FLAGS ON THE OCEAN.
TUE NGT/WED NGT...SUB-SCA CONDITIONS. SHOWERS/FOG POSSIBLE.
THU...SCA FLAGS POSSIBLE FOR THE OCEAN.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR
ANZ450>455.
SMALL CRAFT ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR ANZ430-
431.
&&
$$
SYNOPSIS...O`HARA
NEAR TERM...GIGI/HEAVENER
SHORT TERM...GIGI
LONG TERM...O`HARA
AVIATION...GIGI/O`HARA
MARINE...GIGI/O`HARA
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
131 AM EST SUN JAN 12 2014
.SYNOPSIS...
AN INTENSIFYING LOW PRESSURE SYSTEM OVER SOUTHERN CANADA WILL
CAUSE ITS ASSOCIATED COLD FRONT TO CROSS THE REGION OVERNIGHT.
HIGH PRESSURE WILL THEN BUILD OVER THE AREA SUNDAY AND MONDAY,
FOLLOWED BY ANOTHER COLD FRONT ON TUESDAY. A SECONDARY COLD FRONT
IS EXPECTED TO MOVE THROUGH THE AREA WEDNESDAY WITH A LOW PRESSURE
SYSTEM POSSIBLY DEVELOPING ALONG IT NEAR OUR FORECAST AREA. A HIGH
PRESSURE SYSTEM FROM THE SOUTHERN ROCKIES WILL THEN NOSE INTO THE
REGION ON THURSDAY. AN ARCTIC COLD FRONT IS FORECAST TO MOVE
THROUGH THE AREA LATER FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
THE COLD FRONT IS IN THE DELAWARE VALLEY AND WILL BE MOVING
OFFSHORE IN THE NEXT ONE TO TWO HOURS. THE STRONG SHORT WAVE ON
THE LEADING SIDE OF THE TROF IN PA IS MAKING ONE LAST DITCHED
EFFORT TO GENERATE SOME SHOWERS AS IT MOVES THROUGH. WE ADJUSTED
POPS SLIGHTLY FOR THIS FEATURE. HRRR LOOKS WELL TIMED WITH IT.
OTHERWISE VERY FEW OTHER ADJUSTMENTS WERE MADE WITH THIS UPDATE.
ONCE THE FRONT CROSSES THE AREA...WINDS WILL SHIFT TO WEST AND
BECOME SOMEWHAT GUSTY. SKIES WILL REMAIN CLOUDY OVERNIGHT WITH
SOME BREAKS DEVELOPING TOWARDS DAWN. TEMPERATURES WILL FALL
STEADILY AFTER FROPA...REACHING THE MID/UPPER 30S IN MOST AREAS
OVERNIGHT (A FEW LOW 30S UP NORTH).
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM MONDAY/...
A BRISK BUT DRY DAY FOR SUNDAY. WITH THE NORTHWEST FLOW OFF ONTARIO
AND AT LEAST A HIGH ENOUGH INVERSION, WE KEPT THE MENTION OF SOME
SNOW FLURRIES FOR THE POCONOS. ELSEWHERE, MOSTLY SUNNY SKIES SHOULD
OCCUR. A MET/MAV GUIDANCE BLEND WAS USED AND RESULTED IN VERY LITTLE
CHANGE FROM PREVIOUS FORECAST.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
WITH THE ON-GOING AND MONITORING THE RIVER LEVELS DID NOT CHANGE
MUCH BEYOND TUESDAY THOUGH DID BLEND IN SOME NEW 12Z WPC GUIDANCE
WITH OUR PREVIOUS FORECAST.
WE START OFF WITH BUILDING HEIGHTS AND MID-LEVEL RIDGING CONTINUING
TO WORKS ITS WAY IN FROM THE WEST. THIS SHOULD PROVIDE CLEAR SKIES
MONDAY MORNING PROVIDING GOOD RADIATIONAL COOLING CONDITIONS. WITH
THE HEIGHTS RISING SO DO THE TEMPERATURES...AGAIN. DAYTIME HIGHS
SHOULD BE A FEW DEGREES WARMER THAN ON SUNDAY...STILL NEARLY 10
DEGREES ABOVE NORMAL SO OUR THAWING WILL CONTINUE AND WE WILL REMAIN
DRY.
AS FOR NOW, WITH THE NEXT SYSTEM EXPECTED TO ENTER FROM THE WEST
LATE MONDAY NIGHT INTO TUESDAY, THE MID-LEVEL FLOW STILL KEEPS US
UNDER ITS SOUTHWEST INFLUENCE ALLOWING FOR BETTER MOISTURE ADVECTION
AND WARMER TEMPERATURES. AS THE FRONT NEARS RAIN WILL OVERSPREAD
FROM THE SOUTHWEST WITH STRONGER THETA-E ADVECTION AND THEN THE COLD
FRONT SWEEPS THROUGH. THE MID-LEVEL WAVELENGTH APPEARS RATHER LONG
AND THUS A QUICK EXIT IS EXPECTED WITH THIS SYSTEM.
THERE SHOULD BE A PCPN BREAK ON TUESDAY NIGHT BEFORE THE NEXT COLD
FRONT ARRIVES ON WEDNESDAY. HERE A MAJORITY OF THE GUIDANCE SHOWS
MORE OF A POSITIVE TILT TO THE TROUGHING AS IT NEARS FROM THE
WEST-NORTHWEST, THOUGH THE STRENGTH OF THE SYSTEM IS VARIABLE FROM
THE GFS TO THE EC TO THE NHGEM. AGAIN THE MID-LEVEL WAVELENGTH
APPEARS TO BE TOO LONG AND THE QUESTION THEN BECOMES CAN ENOUGH
ENERGY BE PUMPED INTO THE BACKSIDE OF THE TROUGH TO HELP IT SHARPEN
AND CUT ITS WAVELENGTH IN HALF...DOWNSTREAM BLOCKING DOES NOT SEEM
TO HELP THIS A QUICKER SHARPENING. THIS IS FAR FROM BEING ETCHED IN
STONE AND THIS ONE WOULD BE COLD ENOUGH TO HAVE SOME SNOW OCCUR.
AFTER THIS LOW DEPARTS, HIGH PRESSURE WILL BUILD INTO THE REGION.
WHILE TEMPERATURES SHOULD RETURN CLOSER TO NORMAL, THIS HIGH`S
ORIGIN IS FROM THE PACIFIC. SO UNLIKE LAST WEEK`S VERSION, THIS AIR
MASS HAS MORE OF ITS COLDNESS (RELATIVE TO NORMAL) IN THE UPPER HALF
OF THE TROPOSPHERE. THE NEXT COLD FRONT IS SCHEDULED FOR FRIDAY.
THIS ONE MAY BE MOISTURE STARVED. BUT THE ENSUING HIGH BEHIND THIS
FRONT IS COMING FROM WESTERN CANADA AND WILL BRING EVEN COLDER AIR
BACK INTO THE REGION. PLEASE DONT CURB YOUR ENTHUSIASM.
&&
.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THE 06Z TAFS ARE PRIMARILY VFR. WE KEPT SOME MVFR CIGS EARLY AT
KMIV AND KACY UNTIL THE FRONT CLEARS THEM AROUND 07Z. ELSEWHERE A
VFR CIG STARTS THE TAFS ALONG WITH SOME GUSTINESS IN THE NEWFOUND
WESTERLY FLOW. FOG SHOULD NOT BE AN ISSUE ONCE THE FRONT CLEARS,
SO EVEN EASTERNMOST AIRPORTS ARE ABOUT TO LOSE ANY FOG PROBLEMS.
TOWARD MORNING WE DROP THE WIND GUSTS AND ALSO LOSE THE VFR CIG
MAKING IT EITHER CLEAR TOWARD THE COAST OR SCATTERED AT INLAND
AIRPORTS.
THIS MORNING, NORTHWEST WINDS SHOULD INCREASE AND AVERAGE CLOSE TO
15 KTS WITH GUSTS BETWEEN 20 AND 30 KTS. THIS WILL CONTINUE INTO
THE AFTERNOON. CLOUDS: WE DO BRING A TEMPORARY VFR CIG INTO KABE
AND KRDG. ELSEWHERE WE KEPT THE CU/SC DECK AT FEW/SCATTERED
COVERAGE. TOWARD THE COAST WE JUST MENTION SOME CIRRUS.
SUNDAY EVENING AND INTO THE EARLY OVERNIGHT. WINDS WILL DECREASE
RAPIDLY AND ANY CU OR SC CLOUDS WILL DISSIPATE. BY THE MIDDLE/LATE
EVENING MOST TERMINALS WILL HAVE LIGHT AND VARIABLE WINDS.
EXCEPTION IS KPHL WHERE WE BACKED THE (STILL LIGHTER) WINDS TO
THE SOUTHWEST.
OUTLOOK...
MONDAY...VFR. GUSTY SOUTHWEST WINDS DEVELOPING.
MONDAY NIGHT AND TUESDAY...VFR GIVING WAY TO POSSIBLE MVFR IN RAIN.
POSSIBLE RAIN/SNOW MIX WELL NORTH AND WEST OF ABE.
TUESDAY NIGHT...A VFR PERIOD. CONFIDENCE OF TIMING BETWEEN SYSTEMS
IS LOW.
WEDNESDAY...MVFR TO IFR CONDITIONS POSSIBLE. GUSTY NORTHWEST WINDS
LATER WEDNESDAY. CHANGEOVER FROM RAIN TO SNOW POSSIBLE...CONFIDENCE
IS LOW AT THIS POINT.
&&
.MARINE...
VERY LITTLE CHANGE ON THE AFTERNOON UPDATE. GALE WARNINGS CONTINUE
UNTIL 100 AM AND WILL BE FOLLOWED BY SMALL CRAFT ADVISORIES.
WIDESPREAD FOG WITH VISIBILITIES DOWN TO A HALF MILE (AND EVEN LOWER
IN SOME LOCATIONS) WILL CONTINUE UNTIL THE COLD FRONT PASSES THIS
EVENING.
SUNDAY...SMALL CRAFT CONDITIONS ARE EXPECTED...DIMINISHING LATE IN
THE DAY AS THE CAA WEAKENS AS DOES THE WESTERLY FLOW.
OUTLOOK...
MONDAY AND MONDAY NIGHT...POSSIBLE LOW END SMALL CRAFT ADVISORY
CRITERIA IN SOUTHERLY FLOW PRECEDING A COLD FRONT.
TUESDAY...NEAR SMALL CRAFT ADVISORY CRITERIA ON THE OCEAN AS ANOTHER
COLD FRONT MOVES THROUGH. SUB SMALL CRAFT ADVISORY CRITERIA ON
DELAWARE BAY.
TUESDAY NIGHT AND WEDNESDAY...A POSSIBLE SMALL CRAFT ADVISORY LULL
PERIOD WITH AN INCREASING LIKELIHOOD OF SMALL CRAFT ADVISORY CRITERIA
RETURNING BEHIND THE PASSAGE OF THE NEXT COLD FRONT.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR
ANZ450>455.
SMALL CRAFT ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR ANZ430-
431.
&&
$$
SYNOPSIS...GIGI/MIKETTA
NEAR TERM...GIGI/SZATKOWSKI/O`HARA
SHORT TERM...SZATKOWSKI
LONG TERM...GIGI/HEAVENER
AVIATION...GIGI/HEAVENER
MARINE...GIGI/SZATKOWSKI/HEAVENER
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1223 AM EST SUN JAN 12 2014
.SYNOPSIS...
AN INTENSIFYING LOW PRESSURE SYSTEM OVER SOUTHERN CANADA WILL
CAUSE ITS ASSOCIATED COLD FRONT TO CROSS THE REGION OVERNIGHT.
HIGH PRESSURE WILL THEN BUILD OVER THE AREA SUNDAY AND MONDAY,
FOLLOWED BY ANOTHER COLD FRONT ON TUESDAY. A SECONDARY COLD FRONT
IS EXPECTED TO MOVE THROUGH THE AREA WEDNESDAY WITH A LOW PRESSURE
SYSTEM POSSIBLY DEVELOPING ALONG IT NEAR OUR FORECAST AREA. A HIGH
PRESSURE SYSTEM FROM THE SOUTHERN ROCKIES WILL THEN NOSE INTO THE
REGION ON THURSDAY. AN ARCTIC COLD FRONT IS FORECAST TO MOVE
THROUGH THE AREA LATER FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
THE COLD FRONT IS IN THE DELAWARE VALLEY AND WILL BE MOVING
OFFSHORE IN THE NEXT ONE TO TWO HOURS. THE STRONG SHORT WAVE ON
THE LEADING SIDE OF THE TROF IN PA IS MAKING ONE LAST DITCHED
EFFORT TO GENERATE SOME SHOWERS AS IT MOVES THROUGH. WE ADJUSTED
POPS SLIGHTLY FOR THIS FEATURE. HRRR LOOKS WELL TIMED WITH IT.
OTHERWISE VERY FEW OTHER ADJUSTMENTS WERE MADE WITH THIS UPDATE.
ONCE THE FRONT CROSSES THE AREA...WINDS WILL SHIFT TO WEST AND
BECOME SOMEWHAT GUSTY. SKIES WILL REMAIN CLOUDY OVERNIGHT WITH
SOME BREAKS DEVELOPING TOWARDS DAWN. TEMPERATURES WILL FALL
STEADILY AFTER FROPA...REACHING THE MID/UPPER 30S IN MOST AREAS
OVERNIGHT (A FEW LOW 30S UP NORTH).
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM MONDAY/...
A BRISK BUT DRY DAY FOR SUNDAY. WITH THE NORTHWEST FLOW OFF ONTARIO
AND AT LEAST A HIGH ENOUGH INVERSION, WE KEPT THE MENTION OF SOME
SNOW FLURRIES FOR THE POCONOS. ELSEWHERE, MOSTLY SUNNY SKIES SHOULD
OCCUR. A MET/MAV GUIDANCE BLEND WAS USED AND RESULTED IN VERY LITTLE
CHANGE FROM PREVIOUS FORECAST.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
WITH THE ON-GOING AND MONITORING THE RIVER LEVELS DID NOT CHANGE
MUCH BEYOND TUESDAY THOUGH DID BLEND IN SOME NEW 12Z WPC GUIDANCE
WITH OUR PREVIOUS FORECAST.
WE START OFF WITH BUILDING HEIGHTS AND MID-LEVEL RIDGING CONTINUING
TO WORKS ITS WAY IN FROM THE WEST. THIS SHOULD PROVIDE CLEAR SKIES
MONDAY MORNING PROVIDING GOOD RADIATIONAL COOLING CONDITIONS. WITH
THE HEIGHTS RISING SO DO THE TEMPERATURES...AGAIN. DAYTIME HIGHS
SHOULD BE A FEW DEGREES WARMER THAN ON SUNDAY...STILL NEARLY 10
DEGREES ABOVE NORMAL SO OUR THAWING WILL CONTINUE AND WE WILL REMAIN
DRY.
AS FOR NOW, WITH THE NEXT SYSTEM EXPECTED TO ENTER FROM THE WEST
LATE MONDAY NIGHT INTO TUESDAY, THE MID-LEVEL FLOW STILL KEEPS US
UNDER ITS SOUTHWEST INFLUENCE ALLOWING FOR BETTER MOISTURE ADVECTION
AND WARMER TEMPERATURES. AS THE FRONT NEARS RAIN WILL OVERSPREAD
FROM THE SOUTHWEST WITH STRONGER THETA-E ADVECTION AND THEN THE COLD
FRONT SWEEPS THROUGH. THE MID-LEVEL WAVELENGTH APPEARS RATHER LONG
AND THUS A QUICK EXIT IS EXPECTED WITH THIS SYSTEM.
THERE SHOULD BE A PCPN BREAK ON TUESDAY NIGHT BEFORE THE NEXT COLD
FRONT ARRIVES ON WEDNESDAY. HERE A MAJORITY OF THE GUIDANCE SHOWS
MORE OF A POSITIVE TILT TO THE TROUGHING AS IT NEARS FROM THE
WEST-NORTHWEST, THOUGH THE STRENGTH OF THE SYSTEM IS VARIABLE FROM
THE GFS TO THE EC TO THE NHGEM. AGAIN THE MID-LEVEL WAVELENGTH
APPEARS TO BE TOO LONG AND THE QUESTION THEN BECOMES CAN ENOUGH
ENERGY BE PUMPED INTO THE BACKSIDE OF THE TROUGH TO HELP IT SHARPEN
AND CUT ITS WAVELENGTH IN HALF...DOWNSTREAM BLOCKING DOES NOT SEEM
TO HELP THIS A QUICKER SHARPENING. THIS IS FAR FROM BEING ETCHED IN
STONE AND THIS ONE WOULD BE COLD ENOUGH TO HAVE SOME SNOW OCCUR.
AFTER THIS LOW DEPARTS, HIGH PRESSURE WILL BUILD INTO THE REGION.
WHILE TEMPERATURES SHOULD RETURN CLOSER TO NORMAL, THIS HIGH`S
ORIGIN IS FROM THE PACIFIC. SO UNLIKE LAST WEEK`S VERSION, THIS AIR
MASS HAS MORE OF ITS COLDNESS (RELATIVE TO NORMAL) IN THE UPPER HALF
OF THE TROPOSPHERE. THE NEXT COLD FRONT IS SCHEDULED FOR FRIDAY.
THIS ONE MAY BE MOISTURE STARVED. BUT THE ENSUING HIGH BEHIND THIS
FRONT IS COMING FROM WESTERN CANADA AND WILL BRING EVEN COLDER AIR
BACK INTO THE REGION. PLEASE DONT CURB YOUR ENTHUSIASM.
&&
.AVIATION /05Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THE 06Z TAFS ARE PRIMARILY VFR. WE KEPT SOME MVFR CIGS EARLY AT
KMIV AND KACY UNTIL THE FRONT CLEARS THEM AROUND 07Z. ELSEWHERE A
VFR CIG STARTS THE TAFS ALONG WITH SOME GUSTINESS IN THE NEWFOUND
WESTERLY FLOW. FOG SHOULD NOT BE AN ISSUE ONCE THE FRONT CLEARS,
SO EVEN EASTERNMOST AIRPORTS ARE ABOUT TO LOSE ANY FOG PROBLEMS.
TOWARD MORNING WE DROP THE WIND GUSTS AND ALSO LOSE THE VFR CIG
MAKING IT EITHER CLEAR TOWARD THE COAST OR SCATTERED AT INLAND
AIRPORTS.
THIS MORNING, NORTHWEST WINDS SHOULD INCREASE AND AVERAGE CLOSE TO
15 KTS WITH GUSTS BETWEEN 20 AND 30 KTS. THIS WILL CONTINUE INTO
THE AFTERNOON. CLOUDS: WE DO BRING A TEMPORARY VFR CIG INTO KABE
AND KRDG. ELSEWHERE WE KEPT THE CU/SC DECK AT FEW/SCATTERED
COVERAGE. TOWARD THE COAST WE JUST MENTION SOME CIRRUS.
SUNDAY EVENING AND INTO THE EARLY OVERNIGHT. WINDS WILL DECREASE
RAPIDLY AND ANY CU OR SC CLOUDS WILL DISSIPATE. BY THE MIDDLE/LATE
EVENING MOST TERMINALS WILL HAVE LIGHT AND VARIABLE WINDS.
EXCEPTION IS KPHL WHERE WE BACKED THE (STILL LIGHTER) WINDS TO
THE SOUTHWEST.
OUTLOOK...
MONDAY...VFR. GUSTY SOUTHWEST WINDS DEVELOPING.
MONDAY NIGHT AND TUESDAY...VFR GIVING WAY TO POSSIBLE MVFR IN RAIN.
POSSIBLE RAIN/SNOW MIX WELL NORTH AND WEST OF ABE.
TUESDAY NIGHT...A VFR PERIOD. CONFIDENCE OF TIMING BETWEEN SYSTEMS
IS LOW.
WEDNESDAY...MVFR TO IFR CONDITIONS POSSIBLE. GUSTY NORTHWEST WINDS
LATER WEDNESDAY. CHANGEOVER FROM RAIN TO SNOW POSSIBLE...CONFIDENCE
IS LOW AT THIS POINT.
&&
.MARINE...
VERY LITTLE CHANGE ON THE AFTERNOON UPDATE. GALE WARNINGS CONTINUE
UNTIL 100 AM AND WILL BE FOLLOWED BY SMALL CRAFT ADVISORIES.
WIDESPREAD FOG WITH VISIBILITIES DOWN TO A HALF MILE (AND EVEN LOWER
IN SOME LOCATIONS) WILL CONTINUE UNTIL THE COLD FRONT PASSES THIS
EVENING.
SUNDAY...SMALL CRAFT CONDITIONS ARE EXPECTED...DIMINISHING LATE IN
THE DAY AS THE CAA WEAKENS AS DOES THE WESTERLY FLOW.
OUTLOOK...
MONDAY AND MONDAY NIGHT...POSSIBLE LOW END SMALL CRAFT ADVISORY
CRITERIA IN SOUTHERLY FLOW PRECEDING A COLD FRONT.
TUESDAY...NEAR SMALL CRAFT ADVISORY CRITERIA ON THE OCEAN AS ANOTHER
COLD FRONT MOVES THROUGH. SUB SMALL CRAFT ADVISORY CRITERIA ON
DELAWARE BAY.
TUESDAY NIGHT AND WEDNESDAY...A POSSIBLE SMALL CRAFT ADVISORY LULL
PERIOD WITH AN INCREASING LIKELIHOOD OF SMALL CRAFT ADVISORY CRITERIA
RETURNING BEHIND THE PASSAGE OF THE NEXT COLD FRONT.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...GALE WARNING UNTIL 1 AM EST EARLY THIS MORNING FOR ANZ430-431-
450>455.
&&
$$
SYNOPSIS...GIGI/MIKETTA
NEAR TERM...GIGI/SZATKOWSKI/O`HARA
SHORT TERM...SZATKOWSKI
LONG TERM...GIGI/HEAVENER
AVIATION...GIGI/HEAVENER
MARINE...GIGI/SZATKOWSKI/HEAVENER
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
325 PM EST SUN JAN 12 2014
.SYNOPSIS...
19Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS THE SHARP UPPER LEVEL
TROUGH RESPONSIBLE FOR SATURDAYS STORMS NOW WELL EAST INTO THE
WESTERN ATLANTIC. REBOUNDING HEIGHTS AND STRONG SUBSIDENCE IN THE
WAKE OF THIS FEATURE HAVE EXPANDED OVER THE FLORIDA PENINSULA. AN
IMPRESSIVE TONGUE OF DRY MID/UPPER LEVEL AIR IS SEEN IN WATER VAPOR
OVER NORTHERN FLORIDA WITH MOISTURE GRADUALLY INCREASING SOUTHWARD
AS OVERALL SYNOPTIC SUBSIDENCE WEAKENS. 12/12Z KTBW SOUNDING PROFILE
SHOWS THAT THIS DRY AIR EXTENDS THROUGH MUCH OF THE TROPOSPHERE...
WITH IMPRESSIVE DEWPOINT DEPRESSIONS OBSERVED DOWN TO ALMOST 900MB.
THE SYNOPTIC SUBSIDENCE CAN ALSO BE SEEN STRONGLY IN THE COLUMN PW
WHICH DROPPED FROM A HIGH 1.77" LAST EVENING TO A LOW 0.36" BY THIS
MORNING.
LOOKING UPSTREAM IN THE UPPER LEVELS WE SEE WEAK RIDGING EXPANDING
EASTWARD FROM THE CENTRAL CONUS. THIS RIDGING WILL PROVIDE FAIR AND
SEASONABLE WEATHER FOR THE REGION THROUGH MUCH OF MONDAY.
HOWEVER...FURTHER UPSTREAM WE SEE OUR NEXT WEATHER MAKER IN THE FORM
OF A DIGGING TROUGH THROUGH THE INTER-MOUNTAIN WEST. THIS ENERGY
WILL BE QUITE PROGRESSIVE THE NEXT DAY OR TWO AS IT CONTINUES TO
AMPLIFY. THE LARGE SCALE FORCING AND INCREASED RAIN CHANCES
ASSOCIATED WITH THIS NEXT SYSTEM ARE SCHEDULED TO ARRIVE ACROSS
NORTHERN AND CENTRAL FLORIDA BY MONDAY NIGHT. SO...IT WILL BE A
QUICK BOUT OF FAIR WEATHER BETWEEN STORMS...BUT AT LEAST WE MANAGED
TO SALVAGE A SUNNY AND DRY WEEKEND DAY.
AT THE SURFACE...1020+MB HIGH PRESSURE HAS BECOME CENTERED OVER
NORTHERN FLORIDA BY THIS AFTERNOON...AND THEN WILL SHIFT OFF THE
SOUTHEAST CONUS COAST OVERNIGHT.
&&
.SHORT TERM (TONIGHT THROUGH TUESDAY NIGHT)...
EXPECTING A COOLER NIGHT WITH THE DRY AIR IN PLACE AND THE CLOSE
PROXIMITY OF THE SURFACE RIDGE. HOWEVER...THIS AIRMASS IS NOTHING
LIKE THE ONE FROM LAST WEEK...AND WE DO NOT ANTICIPATE ANY
SUB-FREEZING TEMPS TO OCCUR. A FEW VERY ISOLATED PATCHES OF FROST
ARE NOT OUT OF THE QUESTION FOR LEVY COUNTY AT THE NORMALLY COLDER
AND MORE EFFICIENT RADIATIONAL COOLING SITES...BUT EVEN THIS MAY BE
A STRETCH. ELSEWHERE LOW TEMPS BY SUNRISE ON MONDAY WILL RANGE FROM
THE 40S NORTH OF THE I-4 CORRIDOR TO THE UPPER 40S AND LOWER 50S
ACROSS CENTRAL FLORIDA AND THE LOWER/MID 50S DOWN TOWARD FORT MYERS.
MAY SEE SOME INCREASE IN THIN HIGH CIRRUS DURING THE OVERNIGHT...BUT
WILL CONTINUE TO CALL IT MOSTLY CLEAR.
MONDAY/MONDAY NIGHT...UPPER TROUGH AND ASSOCIATED SYNOPTIC FORCING
WILL BEGIN TO SPREAD EASTWARD ALONG THE NORTHERN GULF COAST.
MID/UPPER LEVEL PV ANOMALY DIGGING TOWARD THE CENTRAL GULF COAST AND
AN ASSOCIATED STRONG JET STREAK ALIGNED ALONG AND EAST OF THE MS
VALLEY SHOULD INITIATE WEAK CYCLOGENESIS OVER THE NORTH-CENTRAL GULF
OF MEXICO BAROCLINIC ZONE DURING THE DAY...WITH AN ATTENDANT WARM
FRONT DEVELOPING EASTWARD TO NORTH FLORIDA BY EVENING. MOST OF THE
GLOBAL GUIDANCE DOES NOT SHOW ANY QPF OVER THE NORTHERN NATURE COAST
BEFORE MONDAY NIGHT...HOWEVER NWP GUIDANCE IS ALMOST ALWAYS BIASED
ON THE SLOW SIDE TOWARD COLUMN MOISTENING AND PRECIP INITIATION
WITHIN ISENTROPIC UPGLIDE REGIMES. WITH THIS IN MIND FEEL AT LEAST A
SMALL RAIN CHANCE IS WARRANTED UP TOWARD CITRUS/LEVY COUNTY BY THE
SECOND HALF OF MONDAY AFTERNOON. THE BEST CHANCES
(LIKELY/CATEGORICAL) FOR RAIN OVER NORTHERN AND CENTRAL FLORIDA
WILL THEN ARRIVE MONDAY NIGHT AS THE HEIGHT FALLS/DCVA AND RRQ JET
DYNAMICS BECOME MOST COINCIDENT OVER THE REGION.
TUESDAY/TUESDAY NIGHT..
UPPER LEVEL PV ANOMALY QUICKLY PIVOTS NORTHEASTWARD EARLY TUESDAY
AND IS NOT IN GOOD PHASE WITH THE LOWER LEVEL CYCLONE RESULTING IN
LITTLE IF ANY DEEPENING TO THE LOW AS IT CROSSES GA TOWARD THE
ATLANTIC SEABOARD. TRAILING COLD FRONT WILL SLOWLY SHIFT SOUTH
THROUGH THE DAY WHILE OVERALL SYNOPTIC FORCING FOR ASCENT AND UPPER
JET BOTH WEAKEN OVERHEAD WITH TIME. WITH ALL THIS IN MIND WOULD
EXPECT THE BAND OF SHOWERS/AREAS OF RAIN TO SLOWLY SHIFT SOUTH
THROUGH THE PENINSULA AND BECOME LESS ORGANIZED THROUGH THE DAY. NOT
A SIGNIFICANT PUSH OF COLDER AIR BEHIND THIS FIRST FRONT...SO THE
TEMPERATURE POTENTIAL WILL STILL BE QUITE WARM...IT WILL SIMPLY
DEPEND ON THE DEGREE OF CLOUDS AND SHOWERS. FOR NOW...70S SEEM A
GOOD BET FOR ALL BUT THE FAR NORTHERN NATURE COAST...ESPECIALLY
SINCE MONDAY NIGHT WILL BE AN OVERALL WARM NIGHT FROM WHICH THE
TEMPERATURES CAN BEGIN THEIR DIURNAL RECOVERY. TUESDAY NIGHT...THE
BEST INDICATIONS ARE THAT THE FRONT WILL CLEAR OUR REGION ALONG WITH
ANY LOW LEVEL FOCUS FOR SHOWERS. THE SREF ENSEMBLES HAVE BEEN TRYING
TO KEEP SOME RESIDUAL MOISTURE OVER SOUTH FLORIDA AND WILL KEEP A
SLIGHT CHANCE POP DOWN TOWARD FORT MYERS IN CASE THEY VERIFY.
ELSEWHERE...THE FORECAST IS RAIN-FREE. OUR EYES HOWEVER WILL BE
TURNING TO OUR NORTH AT THIS POINT AS ANOTHER SHARP AND DEEP TROUGH
DIGS INTO THE EASTERN HALF OF THE NATION. THIS TROUGH WILL PROPEL A
MUCH STRONGER FRONT (BUT DRY) THROUGH THE PENINSULA DURING
WEDNESDAY.
POTENTIAL FREEZE EVENT...WHILE STILL SEVERAL DAYS AWAY...GLOBAL
GUIDANCE MEMBERS ARE IN GOOD AGREEMENT OF A MUCH STRONGER BLAST OF
COLD AIR ARRIVING INTO THE PENINSULA BY WEDNESDAY NIGHT. POTENTIAL
FOR FREEZING TEMPERATURES IS CERTAINLY THERE FOR BOTH WEDNESDAY
NIGHT AND THURSDAY NIGHT...ESPECIALLY OVER THE NATURE COAST. LOW
WIND CHILLS ARE LIKELY FOR ALL OF THE REGION WEDNESDAY NIGHT/EARLY
THURSDAY MORNING. THOSE WITH AGRICULTURAL INTEREST OR OUTDOOR PLANS
FOR LATER THIS WEEK SHOULD MONITOR THE LATEST FORECASTS WITH REGARD
TO THIS POTENTIAL FREEZE EVENT.
&&
.LONG TERM (WEDNESDAY THROUGH NEXT SATURDAY)...MODEL SOLUTIONS HAVE
COME INTO BETTER AGREEMENT AND ONLY MINOR DIFFERENCES ARE NOTED
THROUGH THE LONG TERM PERIOD. WEAK HIGH PRESSURE WILL BUILD IN
BEHIND A DEPARTING COLD FRONT TUESDAY NIGHT...WITH ANOTHER
RE-ENFORCING COLD FRONT TAKING AIM ON THE AREA FOR WEDNESDAY. THIS
COLD FRONT WILL SWING THROUGH THE REGION DURING THE DAY ON
WEDNESDAY...WITH HIGH PRESSURE THEN BUILDING BACK INTO THE AREA
THROUGH THE REMAINDER OF THE WORK WEEK. ANOTHER COLD FRONT IS THEN
EXPECTED TO MOVE THROUGH THE AREA FRIDAY NIGHT...WITH HIGH PRESSURE
THEN BUILDING BACK INTO THE REGION OVER THE UPCOMING WEEKEND.
AS FOR FORECAST DETAILS...WILL CARRY SLIGHT CHANCE POPS TUESDAY
NIGHT AS A FEW SHOWERS MAY LINGER OVER SOUTHERN ZONES BEHIND THE
DEPARTING COLD FRONT DURING THE EVENING HOURS. OTHERWISE...EACH
SUCCESSIVE COLD FRONT WILL LACK ANY RETURN FLOW MOISTURE FROM THE
GULF OF MEXICO...SO WE ANTICIPATE DRY FRONTAL PASSAGES AND WILL KEEP
THE FORECAST FREE FROM RAIN. TEMPERATURES ARE EXPECTED TO REMAIN
BELOW NORMAL THROUGH THE LONG TERM PERIOD.
&&
.AVIATION...
12/18Z-13/18Z...VFR WITH FEW-SCT CLOUDS ALTHOUGH SOUTHERN TERMINALS
MAY SEE A FEW MORE CLOUDS AND SOONER AS MOISTURE RETURNS. NORTHERLY
WINDS BECOME LIGHT VARIABLE/EASTERLY OVERNIGHT THEN SE AFTER SUNRISE.
&&
.MARINE...
WINDS AND SEAS CONTINUE TO GRADUALLY SUBSIDE THIS AFTERNOON WITH ALL
HEADLINES NOW DROPPED. WINDS WILL SHIFT EAST AND THEN SOUTHEAST
TONIGHT INTO MONDAY AS HIGH PRESSURE PASSES OFF INTO THE ATLANTIC.
THE NEXT COLD FRONT IS FORECAST TO PASS THROUGH THE EASTERN GULF
MONDAY NIGHT OR EARLY TUESDAY.
&&
.FIRE WEATHER...
AFTER A DRY DAY TO END THE WEEKEND...HIGH PRESSURE WILL SHIFT EAST
AND ALLOW SOME ATLANTIC MOISTURE TO ONCE AGAIN MOVE INTO THE
REGION. TEMPERATURES WILL BE WARMER ON MONDAY...HOWEVER WITH THE
INCREASING LOW LEVEL MOISTURE...NO CRITICAL LEVELS OF RELATIVE
HUMIDITY ARE ANTICIPATED. A WEAK COLD FRONT WILL CROSS THE REGION
MONDAY NIGHT AND TUESDAY WITH ANOTHER BOUT OF SHOWERS AND STORMS. A
STRONGER COLD FRONT WILL THEN CROSS THE REGION ON WEDNESDAY USHERING
IN A VERY DRY AND WELL BELOW NORMAL TEMPERATURE REGIME FOR THE END
OF THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 53 76 65 71 / 10 10 70 60
FMY 57 82 66 77 / 10 10 40 50
GIF 50 78 61 73 / 10 10 60 60
SRQ 53 76 67 71 / 0 10 60 60
BKV 41 76 62 71 / 10 10 80 60
SPG 57 76 66 69 / 10 10 70 60
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/MARINE/FIRE WX...MROCZKA
AVIATION...RUDE
LONG TERM...JELSEMA
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
1000 AM EST SUN JAN 12 2014
.UPDATE...
15Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS THE SHARP UPPER LEVEL
TROUGH RESPONSIBLE FOR SATURDAYS STORMS NOW QUICKLY EXITING EAST
INTO THE WESTERN ATLANTIC. REBOUNDING HEIGHTS AND STRONG
SUBSIDENCE IN THE WAKE OF THIS FEATURE HAVE EXPANDED OVER THE
FLORIDA PENINSULA. AN IMPRESSIVE TONGUE OF DRY MID/UPPER LEVEL AIR
IS SEEN IN WATER VAPOR OVER NORTHERN FLORIDA WITH MOISTURE GRADUALLY
INCREASING SOUTHWARD AS OVERALL SYNOPTIC SUBSIDENCE WEAKENS. 12/12Z
KTBW SOUNDING PROFILE SHOWS THAT THIS DRY AIR EXTENDS THROUGH MUCH
OF THE TROPOSPHERE...WITH IMPRESSIVE DEWPOINT DEPRESSIONS
OBSERVED DOWN TO ALMOST 900MB. THE SYNOPTIC SUBSIDENCE CAN ALSO
BE SEEN STRONGLY IN THE COLUMN PW WHICH DROPPED FROM A HIGH 1.77"
LAST EVENING TO A LOW 0.36" BY THIS MORNING.
LOOKING UPSTREAM IN THE UPPER LEVELS WE SEE WEAK RIDGING EXPANDING
EASTWARD FROM THE CENTRAL CONUS. THIS RIDGING WILL PROVIDE FAIR AND
SEASONABLE WEATHER FOR THE REGION THROUGH MUCH OF MONDAY.
HOWEVER...FURTHER UPSTREAM WE SEE OUR NEXT WEATHER MAKER IN THE FORM
OF A DIGGING TROUGH THROUGH THE INTER-MOUNTAIN WEST. THIS ENERGY
WILL BE QUITE PROGRESSIVE THE NEXT DAY OR TWO AS IT CONTINUES TO
AMPLIFY. THE LARGE SCALE FORCING AND INCREASED RAIN CHANCES
ASSOCIATED WITH THIS NEXT SYSTEM ARE SCHEDULED TO ARRIVE ACROSS
NORTHERN AND CENTRAL FLORIDA BY MONDAY NIGHT. SO...IT WILL BE A
QUICK BOUT OF FAIR WEATHER BETWEEN STORMS...BUT AT LEAST WE MANAGED
TO SALVAGE A SUNNY AND DRY WEEKEND DAY.
AT THE SURFACE...1020+MB HIGH PRESSURE WILL BECOME CENTERED OVER
NORTHERN FLORIDA BY THIS AFTERNOON...AND THEN SHIFT OFF THE
SOUTHEAST CONUS COAST OVERNIGHT.
WITH ALL THE DRY AIR AND SUBSIDENCE ALOFT...OUR SKIES ARE MOSTLY
CLEAR LATE THIS MORNING AND EXPECT THIS TO CONTINUE THROUGH THE
REMAINDER OF THE DAY. A BIT COOLER AIRMASS HAS ARRIVED COMPARED TO
THE TEMPS AND DEWPOINTS ON SATURDAY...HOWEVER AFTERNOON HIGHS IN THE
MID/UPPER 60S NORTH AND MIDDLE 70S SOUTH ARE STILL QUITE SEASONABLE
FOR MID JANUARY.
EXPECTING A COOLER NIGHT WITH THE DRY AIR IN PLACE AND THE CLOSE
PROXIMITY OF THE SURFACE RIDGE. HOWEVER...THIS AIRMASS IS NOTHING
LIKE THE ONE FROM LAST WEEK...AND WE DO NOT ANTICIPATE ANY
SUB-FREEZING TEMPS TO OCCUR. A FEW VERY ISOLATED PATCHES OF FROST
ARE NOT OUT OF THE QUESTION FOR LEVY COUNTY AT THE NORMALLY COLDER
AND MORE EFFICIENT RADIATIONAL COOLING SITES...BUT EVEN THIS MAY BE
A STRETCH. ELSEWHERE LOW TEMPS BY SUNRISE ON MONDAY WILL RANGE FROM
THE 40S NORTH OF THE I-4 CORRIDOR TO THE UPPER 40S AND LOWER 50S
ACROSS CENTRAL FLORIDA AND THE LOWER/MID 50S DOWN TOWARD FORT MYERS.
MAY SEE SOME INCREASE IN THIN HIGH CIRRUS DURING THE OVERNIGHT...BUT
WILL CONTINUE TO CALL IT MOSTLY CLEAR.
MONDAY...UPPER TROUGH AND ASSOCIATED SYNOPTIC FORCING WILL BEGIN TO
SPREAD EASTWARD ALONG THE NORTHERN GULF COAST. MID/UPPER LEVEL PV
ANOMALY DIGGING TOWARD THE CENTRAL GULF COAST AND AN ASSOCIATED
STRONG JET STREAK ALIGNED ALONG AND EAST OF THE MS VALLEY SHOULD
INITIATE WEAK CYCLOGENESIS OVER THE NORTH-CENTRAL GULF OF MEXICO
BAROCLINIC ZONE DURING THE DAY...WITH AN ATTENDANT WARM FRONT
DEVELOPING EASTWARD TO NORTH FLORIDA BY EVENING. MOST OF THE
GLOBAL GUIDANCE DOES NOT SHOW ANY QPF OVER THE NORTHERN NATURE COAST
BEFORE MONDAY NIGHT...HOWEVER NWP GUIDANCE IS ALMOST ALWAYS BIASED
ON THE SLOW SIDE TOWARD COLUMN MOISTENING AND PRECIP INITIATION
WITHIN ISENTROPIC UPGLIDE REGIMES. WITH THIS IN MIND FEEL AT LEAST A
SMALL RAIN CHANCE IS WARRANTED UP TOWARD CITRUS/LEVY COUNTY BY THE
SECOND HALF OF MONDAY AFTERNOON. THE BEST CHANCES FOR RAIN OVER
NORTHERN AND CENTRAL FLORIDA WILL THEN ARRIVE MONDAY NIGHT AS THE
HEIGHT FALLS/DCVA AND RRQ JET DYNAMICS BECOME MOST COINCIDENT OVER
THE REGION.
WHILE STILL SEVERAL DAYS AWAY...GLOBAL GUIDANCE MEMBERS ARE IN
AGREEMENT OF A BRIEF...BUT MUCH STRONGER BLAST OF COLD AIR ARRIVING
INTO THE PENINSULA DURING WEDNESDAY. POTENTIAL FOR FREEZING
TEMPERATURES IS CERTAINLY THERE FOR BOTH WEDNESDAY NIGHT AND
THURSDAY NIGHT...ESPECIALLY OVER THE NATURE COAST. LOW WIND CHILLS
ARE LIKELY FOR ALL OF THE REGION WEDNESDAY NIGHT/EARLY THURSDAY
MORNING. WE WILL CONTINUE TO MONITOR THIS POTENTIAL FREEZE EVENT FOR
LATER IN THE WEEK.
&&
.AVIATION...
12/12Z-13/12Z...VFR PREVAIL WITH FEW-SCT CLOUDS. NORTHERLY WINDS
GRADUALLY BECOME NORTHEASTERLY.
&&
.MARINE...
NORTHERLY FLOW IN THE WAKE OF A COLD FRONT CONTINUES TO RESULT IN
CAUTIONARY LEVEL WINDS AND SEAS OVER THE OFFSHORE WATERS THIS
MORNING. THESE CONDITIONS WILL GRADUALLY SUBSIDE INTO THE AFTERNOON
HOURS WITH ALL HEADLINES DROPPED BY THIS EVENING. WINDS WILL SHIFT
EAST AND THEN SOUTHEAST TONIGHT INTO MONDAY AS HIGH PRESSURE PASSES
EAST OF THE REGION. THE NEXT COLD FRONT IS FORECAST TO PASS THROUGH
THE EASTERN GULF MONDAY NIGHT OR EARLY TUESDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 71 52 73 66 / 0 10 10 70
FMY 76 55 79 67 / 0 10 10 40
GIF 73 50 77 64 / 0 10 10 60
SRQ 71 53 75 66 / 0 0 10 60
BKV 70 43 75 61 / 0 10 10 70
SPG 70 55 74 67 / 0 10 10 70
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE...MROCZKA
AVIATION...RUDE
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
924 PM CST MON JAN 13 2014
.UPDATE...
ISSUED AT 913 PM CST MON JAN 13 2014
JUST ISSUED A WINTER WEATHER ADVISORY ALONG AND NORTH OF HIGHWAY
30 FOR TUESDAY. THE ADVISORY IS FOR A COMBINATION OF STRONG
WINDS...SNOW AND BLOWING SNOW. THE 00Z NAM AS WELL AS THE LATEST
HRRR AND RUC13 STILL SUGGEST ACCUMULATING SNOW SPREADING OVER THE
AREA FROM EARLY TUESDAY MORNING THROUGH MID MORNING. THERE MAY BE
A MIX AT THE ONSET ESPECIALLY SOUTH OF I80 BUT TO THE NORTH IT
SHOULD BE BRIEF IF AT ALL. 18Z/00Z MODELS ARE SHOWING MID LEVEL
LAPSE RATES IN THE 7 TO 8 C/KM RANGE WHEN THE SNOW MOVES THROUGH
SUGGESTING A CONVECTIVE NATURE TO THE SNOW. THE LAST FEW RUNS OF
THE HRRR HAS BEEN SHOWING SOME STRONG REFLECTIVITIES OVER THE NORTH
THIRD BETWEEN 12Z AND 15Z. I/M NOT SURE IT WILL THUNDER...BUT IT
CERTAINLY LOOKS AT LEAST LIKE SOME BRIEF BUT HEAVY BURSTS OF SNOW
FOR SOME AREAS TOMORROW MORNING. KEPT AMOUNTS IN THE 1 TO 2 INCH
RANGE BUT ADDED THE LOCALLY HIGHER CAVEAT WITH THE POTENTIAL
CONVECTION. THE WIND SHOULD KICK WEST TO EAST MID TO LATE MORNING.
MENTIONED GUSTS UP TO 45 MPH BUT THIS COULD BE CONSERVATIVE. MODEL
SOUNDINGS ARE SHOWING A SHALLOW SURFACE BASED MIXED LAYER
DEVELOPING WITH THE ARRIVAL OF THE COLDER AIR. WIND GUSTS AT THE
TOP OF THE MIX LAYER ARE PROGGED TO BE 40 TO 45 KTS. IF MODELS
MAINTAIN THESE STRONG ELEVATED WINDS IN LATER RUNS THEN THIS COULD
LEAD TO A WIND ADVISORY BEING ISSUED LATER TONIGHT...SOUTH OF THE
CURRENT WINTER WX ADVISORY. GUSTY WINDS WILL CONTINUE INTO THE
EVENING BUT SHOULD DIMINISH ENOUGH TO END ANY SIGNIFICANT BLOWING
SNOW.
&&
.SYNOPSIS...
ISSUED AT 230 PM CST MON JAN 13 2014
A DYNAMIC AND CHALLENGING FORECAST THE NEXT 24 HOURS. ANALYSIS AND
VERIFICATION AT NOON INDICATE A FAST MOVING AND QUITE INTENSE
ALBERTA CLIPPER SYSTEM IS DIVING RAPIDLY SE AND IS NOW MOVING INTO
MONTANA AS OF 2 PM CST. PRESSURE RISE/FALL COUPLETS...WINDS AND
PRESSURE ALL INDICATE SYSTEM IS STRONGER AND DIGGING MORE THAN
MOST SOLUTIONS FROM 12Z. THIS SUPPORTS OCCLUSION AND PRECIPITATION
DEVELOPING TO EXPLODE BEFORE IT GETS TO FORECAST AREA. THE HIGH NON
LINEARITY OF THE IMBALANCES DUE TO ACCELERATIONS (NON-HYDROSTATIC)
AND MIXING (NON-ADIABATIC) SUGGEST LOTS OF CHANGEABLE WEATHER WITH
IMPACTS ON TRACKS OF SNOW AMOUNTS TONIGHT INTO TUESDAY...WIND AND
WIND GUSTS. LOCAL TOOLS AND TECHNIQUES ALL SUGGEST NORTHERN 1/2 OF
AREA THE BIGGEST AFFECTED WITH ISOLATED THUNDER POSSIBLE WITH LOBE
ON INTENSE BUT NARROW SNOW BAND PASSING TOWARD MORNING. UPSTREAM
ENERGY AND ANALYSIS INDICATE MORE CHANGEABLE WEATHER WITH A LARGER
AND STRONGER SYSTEM THURSDAY INTO FRIDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 230 PM CST MON JAN 13 2014
TONIGHT...ONE OF THE STRONGER ALBERTA CLIPPER TO AFFECT FORECAST
AREA LATE TONIGHT WELL INTO TUESDAY. WARM ADVECTION WING SNOW WITH
SOME SLEET AND RAIN FAR SE SECTIONS THAT WILL CHANGE TO SNOW DUE
TO EVAPORATIVE COOLING WILL BLOOM ACROSS MID PORTIONS OF IOWA
AROUND OR JUST BEFORE MIDNIGHT. THIS AREA WILL REACH NEAR THE MISSISSIPPI
RIVER VALLEY AROUND 6 AM WITH ISOLATED THUNDER POSSIBLE PER "LIFT"
TOOL ALONG AND NORTH OF I-80. EXPECT A 10-30 MILE WIDE BAND OF 30-40+
DBZ ECHOES WITH SNOWFALL RATES OF 1+ INCH AN HOUR THAT MAY LAST
ANYWHERE FROM 15 MINUTES TO OVER AN HOUR. MOST LOCATIONS WILL PICK
UP .75 TO NEAR 2 INCHES ALONG AND NORTH OF I-80 WITH HEAVIEST SNOWS
NORTH OF TRIPLE POINT ALONG AND NORTH OF HIGHWAY 30. THE SNOW WILL
DIMINISH TO FLURRIES OR LIGHT SNOW BY MID MORNING TUESDAY. SKIES
WILL BECOME OVERCAST BY MIDNIGHT WITH SOUTH WINDS INCREASING TO TO
20+ MPH OVERNIGHT. MINS 25 TO 32 DEGREES FROM NORTH TO SOUTH WITH
LOWS MAINLY BEFORE MIDNIGHT WITH RISING TEMPERATURES OVERNIGHT.
TUESDAY...MAIN ISSUE WILL BE STRONG AND VERY GUSTY WINDS. STRONG
COLD FRONT WITH SNOWS DIMINISHING TO FLURRIES BY MID/LATE MORNING
WITH NW WINDS ARRIVING FROM NW TO SE BETWEEN 6 AM AND 11 AM. LOCAL
TOOLS ALL INDICATE 25 TO 35+ MPH WITH SOME GUSTS AROUND 45 MPH
THAT WILL BE VERY CLOSE TO WIND ADVISORY CRITERIA WITH MINOR
BLOWING AND DRIFTING SNOW DUE TO ONLY 1 TO 2 INCHES OF NEW SNOW
EXPECTED. TEMPERATURES TO FALL SIGNIFICANTLY BEHIND THE FRONT INTO
THE LOW/MID TWENTIES TOWARD DUSK WITH UPPER TEENS POSSIBLE FAR NW
SECTIONS. LATER SHIFTS MAY NEED TO ISSUE WIND ADVISORY IF TRENDS
CONTINUE. A WINTER WEATHER ADVISORY MAY ALSO BE AN OPTION IF SNOWS
LINGER AND ARE A BIT HIGHER ON SNOW AMOUNTS. NICHOLS
.LONG TERM...(TUESDAY NIGHT THROUGH NEXT MONDAY)
ISSUED AT 230 PM CST MON JAN 13 2014
TUESDAY NIGHT AND WEDNESDAY...BRISK NORTHWEST WINDS OF 15 TO 25 MPH
TO CONTINUE INTO TUE EVENING...AND PROBABLY NOT DROPPING OFF TO
10-15 MPH TIL LATE IF BULK OF WRAP AROUND STRATUS MAINTAINS ACRS THE
AREA. MORE ORGANIZED LIGHT SNOW OR SHOWERS WILL BE EXITING OFF TO
THE EAST DURING THE EVENING...BUT DEEPENING CYCLONIC FLOW COULD
CONTINUE TO WRING OUT FLURRIES ACRS MUCH OF THE FCST AREA WELL INTO
THE NIGHT. LATEST MODEL RUNS CONTINUE TO VARY ON HOW COLD IT WILL
GET BY WED MORNING...AND IF CLOUDS AND BRISK MIXING WINDS LINGER
INTO WED MORNING THE MILDER OF THE LOW TEMP GUIDANCE MAY VERIFY
BETTER. BUT STRENGTH OF LLVL COLD AIR ADVECTION ALSO MUST BE TAKEN
INTO ACCOUNT AND FEEL A BLEND OF ALL SOLUTIONS MAY TAKE ALL OF THESE
VARIABLES INTO ACCOUNT. WIND CHILLS MAY STILL GET TO 10 BELOW IN THE
NORTHWESTERN CWA BY EARLY WED MORNING. A PASSING BOUT OF BOTH SFC
AND UPPER RIDGING TO MAKE FOR A FAIR WX DAY WED WITH LATE DAY RETURN
FLOW HELPING TEMPS RECOVER BACK INTO THE UPPER TEENS TO MID 20S BY
LATE AFTERNOON. THEN AN INTENSE ALBERTA TYPE CLIPPER LOW PRESSURE
SYSTEM STILL BEING SLATED BY THE MODELS TO RIDE ACRS NORTHWEST
PACIFIC RIDGE AND DUMP DOWN TOWARD THE WESTERN LK SUPERIOR BSN
THROUGH THU MORNING. WILL THROW OUT THE 12Z GFS WHICH KEEPS THE DVN
CWA DRY OVERNIGHT AND THE SOUTHEASTERN FLANKING WARM AIR ADVECTION
WING OF SNOW TO THE NORTH OF US...WHILE THE BULK OF THE OTHER
SOLUTIONS SWEEP SOME TYPE OF ELEVATED SNOW BAND ACRS PORTIONS OF THE
AREA INTO EARLY THU MORNING. WILL EXPAND THE CHC POPS SOUTHWARD.
SOME LIGHT SNOW ACCUMULATIONS MAY EVEN OCCUR ESPECIALLY NORTH OF I80
BY 12Z THU. AS FOR TEMPS...WITH STRENGTHENING SOUTHWESTERLY LLVL
FLOW ACRS THE AREA TO THE LEE OF THIS SYSTEM...LOW TEMPS MAY OCCUR
THE FIRST FEW HOURS OF THE EVENING AND THEN RISE OVERNIGHT INTO THU
MORNING. BUT EVAPO-COOLING FROM ANY PRECIP WING MAY MAKE FOR STEADY
TEMP PERIODS AS WELL.
THURSDAY AND FRIDAY...SUB 990 MB LOW CENTER WILL BE LOOKING TO DIG
DOWN ACRS THE NORTHWESTERN INTO CENTRAL GRT LKS THU. LATEST PLACEMENT
AND HANDLING ON 12Z MEDIUM RANGE SOLUTIONS GENERALLY SUGGEST THAT
AFTER WHAT EVEN WAA WING OF PRECIP THAT MANAGES TO MAKE IT ACRS THE
LOCAL ARE CLEARS OFF TO THE EAST THU MORNING...THE DVN CWA WILL
TEMPORARILY BE IN A DRY SLOT AND TYPE OF WARM SECTOR...BEFORE A VERY
STRONG IN-WRAPPING LLVL COLD CONVEYOR SURGES SOUTHEASTWARD ACRS ALL
OF IA BY AFTERNOON AND INTO THE EVENING. RATHER MILD HIGHS IN THE
30S MAY OCCUR THU MORNING...BEFORE TEMPS FALL OFF AGAIN. BUT THE
MAIN WX STORY STILL LOOKS LIKE WILL BE THE VERY STRONG WINDS SURGING
ACRS THE AREA LATER THU AFTERNOON AND LASTING WELL INTO THE OVERNIGHT
THU NIGHT. VERY TIGHT LLVL CYCLONIC PRESSURE GRADIENT...A PROBABLE
VERY LARGE PRESSURE RISE-FALL COUPLET TO ENHANCE ISALLOBARIC SURGE
COMPONENT TO THE WINDS...AND EARLY SIGNS OF A TROP-FOLD DOWN TO
UNDER 550 MB ROTATING ACRS THE REGION THU EVENING SHOULD MAKE FOR
HIGHER END WIND ADVISORY CRITERIA TO BE MET IN OR VERY CLOSE TO THE
CWA. EARLY INDICATIONS STILL POINT AT GUSTS OF 45 TO NEAR 50 MPH BY
THUR EVENING. THESE STRONG WINDS IN WRAP AROUND SNOW SHOWERS THU
EVENING AND INTO THE OVERNIGHT MAY MAKE FOR GREATLY REDUCED LOCALIZED
VSBYS. GENERAL ENSEMBLES AND GFS/ECMWF AGREEMENT ALSO POINT TO -20C
H85 MB COLD POOL TO GET ADVECTED DOWN ACRS THE AREA THU NIGHT INTO
FRI MORNING. DESPITE MIXING WINDS AND CLOUD COVER...STOUT LLVL COLD
AIR ADVECTION TO DRIVE TEMPS INTO THE LOWER SINGLE DIGITS ABOVE
ZERO...TO LOWER TEENS THROUGH FRI MORNING. WIND CHILL ADVISORY
CRITERIA MAY BE NEARED IN THE NORTHWESTERN THIRD OF THE CWA BY EARLY
FRI MORNING. INCOMING RIDGE GRADIENT TO CONTINUE TO MAKE FOR
BLUSTERY CONDITIONS ON FRI UNTIL WIND DECREASE BY LATE AFTERNOON AS
UPSTREAM RIDGE DRAWS CLOSER. THE NEW 12Z ECMWF EVEN SUGGESTS AT
SOME RENEWED DIURNAL SNOW SHOWER DEVELOPMENT FRI MORNING BEFORE THEY
DECAY AGAIN IN THE AFTERNOON. BRUNT OF LLVL COLD POOL PROGGED TO
SLIDE EAST OF THE AREA BY FRI AFTERNOON...BUT STILL SEE DAYTIME
HIGHS STRUGGLING TO RECOVER TO THE GUIDANCE SUGGESTED LOW TO MID
TEENS NORTH OF I80...UPPER TEENS SOUTH. RIDGE OVERHEAD...SFC WIND
DECOUPLE AND CLOUD CLEAR-OFF MAY MAKE FOR A SUBZERO NIGHT
IN PORTIONS OF THE DVN CWA. BUT THE 1Z GFS SHUTTLES A CLIPPER DOWN IN
FRESHLY HIGH AMPLIFIED NORTHERLY FLOW TO THE WEST OF DEEP EASTERN
CONUS TROF BASE. THUS THIS MODEL STARTS TO WARM AIR ADVECT
OVERNIGHT AS WELL AS PRODUCE 1-3+ INCHES OF SNOW IN THE NORTHEASTERN
THIRD OF THE DVN CWA BY SAT MORNING. BULK OF OTHER MEDIUM RANGE
SOLUTIONS ARE DRY AND COLD AND WILL SIDE THAT WAY FOR NOW. PROBABLY
NOT COLD ENOUGH FOR FRI NIGHT LOWS.
SATURDAY THROUGH NEXT MONDAY...MODEL RUN VARIANCES BETWEEN SOLUTIONS
AND THE PREVIOUS RUNS OF THEMSELVES CONTINUE FOR NEXT WEEKEND. BUT
AGAIN...ASSESSING THE GENERAL TRENDS AND BEHAVIOR OF UPPER JET
DYNAMICS SUGGEST A TEMPORARY FLATTENING OUT OF THE MEAN FLOW PATTERN
ACRS MUCH OF THE CENTRAL INTO EASTERN CONUS AND EVENTUAL TEMP
MODERATION BACK INTO THE 30S OF SUNDAY INTO MONDAY. NOT MUCH IN THE
WAY OF ORGANIZED PRECIP MAKERS EVIDENT AT THIS POINT AS WELL DURING
THIS PERIOD. BUT TRENDS IN THE OSCILLATIONS AND SOME INFLUENCE OFF
THE NORTH PACIFIC...POINT TO THE COLD CORE L/W TROF SNAPPING BACK
INTO PLACE ACRS THE CENTRAL INTO EASTERN CONUS BY MID NEXT WEEK.
BOTH THE 12Z RUN GFS AND ECMWF SEEM TO BE PICKING UP ON THIS IDEA
WITH ANOTHER SIGNIFICANT ARCTIC SURGE FLOWING DOWN ALONG AND EAST OF
THE MS RVR VALLEY NEXT TUE NIGHT INTO WED...WHILE THE POLAR VORTEX
TRIES TO MIGRATE SOUTH OF JAMES BAY AGAIN. UPPER RIDGES TO AGAIN
REIGN OFF THE COASTS. ..12..
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 542 PM CST MON JAN 13 2014
STRONG LOW PRESSURE SYSTEM OVER THE NORTHERN PLAINS WILL MOVE
RAPIDLY SOUTHEAST REACHING SOUTHWESTERN WI TUESDAY MORNING. THE
SYSTEM WILL BRING RAPIDLY CHANGING CONDITIONS TO THE AREA LATE
TONIGHT AND TUESDAY MORNING. AROUND 09Z SNOW WILL BEGIN IN THE WEST
WITH THE SNOW SPREADING EAST TO THE MISSISSIPPI RIVER BY 12Z.
AREAS NORTH OF THE HIGHWAY 30 COULD SEE A BRIEF...LESS THAN ONE
HOUR...PERIOD OF FREEZING RAIN MIXED WITH THE SNOW WHILE TO THE
SOUTH SURFACE TEMPERATURES WILL BE WARM ENOUGH FOR A BRIEF
RAIN/SNOW MIX. ANY MIXED PCPN WILL QUICKLY CHANGE TO SNOW. SOME
ISOLATED THUNDER CAN/T BE RULED OUT ACROSS THE NORTH EARLY TUESDAY
MORNING. WINDS WILL BEGIN TO INCREASE AROUND MID MORNING FROM THE
NORTHWEST WITH SUSTAINED WINDS AROUND 25 KTS AND GUSTS TO AROUND
35KTS. THE STRONG WIND WITH NEW SNOWFALL WILL CAUSE BLOWING SNOW
WITH THE LOWEST CONDITIONS NORTH THROUGH THE AFTERNOON. SO IN A
NUTSHELL VFR CONDITIONS THIS EVENING LOWERING MVFR/IFR TOWARD
MORNING AND CONTINUING THROUGH NOON WITH STRONG NORTHWEST WINDS.
CONDITIONS SHOULD IMPROVE TO MVFR DURING THE AFTERNOON BUT IT WILL
REMAIN QUITE WINDY.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WINTER WEATHER ADVISORY FROM 5 AM TO 6 PM CST TUESDAY FOR BENTON-
BUCHANAN-CLINTON-DELAWARE-DUBUQUE-JACKSON-JONES-LINN.
IL...WINTER WEATHER ADVISORY FROM 5 AM TO 6 PM CST TUESDAY FOR
CARROLL-JO DAVIESS-STEPHENSON-WHITESIDE.
MO...NONE.
&&
$$
UPDATE...DLF
SYNOPSIS...NICHOLS
SHORT TERM...NICHOLS
LONG TERM...12
AVIATION...DLF
AREA FORECAST DISCUSSION
NWS JACKSON KY
1038 PM EST MON JAN 13 2014
.UPDATE...
ISSUED AT 1037 PM EST MON JAN 13 2014
RAIN CONTINUES ACROSS CENTRAL AND EASTERN KY...AND ALTHOUGH IT IS
BECOMING SLIGHTLY MORE SCATTERED IN NATURE...IT DOES NOT SHOW MUCH IN
THE WAY OF EASTWARD MOVEMENT BASED ON LATEST RADAR TRENDS. AS A
RESULT...UPDATED POPS AND WEATHER TO DELAY THE EXIT OF THE RAIN ONCE
MORE. LATEST HRRR INITIATED WELL WITH ONGOING CONDITIONS...SO LEANED
TOWARDS THIS MODEL...AS WELL AS CURRENT TRENDS...TO COME UP WITH
TIMING OVER THE REST OF TONIGHT. CIGS ARE SHOWING SIGNS OF LOWERING
ACROSS THE REGION...AND EXPECT THESE LOW CLOUDS TO CONTINUE THROUGH
THE REST OF THE NIGHT. OTHERWISE...TEMPERATURES HAVE REMAINED NEARLY
STEADY...WITH ONLY MINOR UPDATES TO INCLUDE THE LATEST OBSERVATIONS
NEEDED.
UPDATE ISSUED AT 714 PM EST MON JAN 13 2014
PUSHED BACK THE TIMING OF THE EXITING RAINFALL BY A COUPLE OF
HOURS...AS LATEST RADAR RETURNS AND HI RES MODEL GUIDANCE ARE BOTH
SUPPORTING THIS TREND. IN FACT...MAY NEED TO CONTINUE TO UPDATE TO
SLOW THE TIMING EVEN MORE OVER THE NEXT FEW HOURS BASED ON THE LATEST
RADAR TRENDS. WILL CONTINUE TO MONITOR. ALSO...LATEST SOUNDINGS DO
SUGGEST MOIST CONDITIONS NEAR THE SURFACE AS DRY AIR FILTERS IN ALOFT
LATE TONIGHT INTO TOMORROW MORNING. EXPECT THIS MOISTURE TO FORM
ITSELF INTO A LOW STRATUS DECK...BUT SOME PATCHY FOG DEVELOPMENT
CANNOT BE RULED OUT...ESPECIALLY IN THE VALLEYS.
OTHERWISE...TEMPERATURES AND WINDS SEEM TO BE ON TRACK. DID BLEND IN
THE LATEST OBSERVATIONAL DATA JUST TO MAKE SURE...BUT LITTLE CHANGES
WERE MADE TO THE ONGOING FORECAST.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 322 PM EST MON JAN 13 2014
AN ACTIVE SHORT TERM FORECAST PERIOD LOOKS TO BE IN STORE AS IT WILL
BE HIGHLIGHTED BY A COUPLE OF QUICK MOVING SYSTEMS. THE 20Z ANALYSIS
ACROSS THE REGION SHOWS A COLD FRONT OVER THE GREAT LAKES AND A
DEVELOPING LOW OVER THE MID MS VALLEY BRINGING A FRONT INTO THE LOWER
OHIO VALLEY AND TN VALLEY. AHEAD OF THESE...WARMER TEMPS AND ABUNDANT
MOISTURE CONTINUE TO SURGE INTO THE AREA WITH A GOOD SWATH OF RAIN
STILL MOVING THROUGH THE STATE OF KENTUCKY AND INTO EASTERN PORTIONS.
MODELS ARE IN GOOD AGREEMENT THAT THE 500MB TROUGH WILL SWING THROUGH
EASTERN KENTUCKY BY ABOUT 14Z TUESDAY MORNING BRINGING AN END TO THE
RAINFALL. THE UPPER LEVEL PATTERN MAINTAINS ITS PROGRESSIVE
CHARACTERISTICS TO IT AS ALL THE MOISTURE EXITS THE AREA BEFORE THE
COLDER AIR IS ADVECTED IN SO NO SNOW IS EXPECTED BEHIND THIS SYSTEM.
BUT A GOOD SHOT OF MOISTURE FOR THIS EVENT WILL LEAVE A BIT HIGHER
RAINFALL TOTALS THAN ADVERTISED SO BUMPED UP QPF AMOUNTS A TAD.
HEADING INTO TUESDAY...THE PREVIOUS SYSTEM EXITS AND ANOTHER QUICK
MOVING SHORT WAVE DIVES OUT OF CANADA INTO THE OHIO VALLEY AS IT
ROTATES THROUGH THE BASE OF STUBBORN LONGWAVE TROUGH OVER THE UPPER
GREAT LAKES. THE VORT MAX WITH THIS WAVE LOOKS TO BE PRETTY STOUT AND
WITH A GOOD SHOT OF MOISTURE AS RAIN SHOWERS WILL MOVE INTO EASTERN
KENTUCKY BY TUESDAY EVENING. THE COLDER AIR WILL MOVE IN WITH THIS
FRONT QUITE QUICKLY AS RAIN SHOULD CHANGE TO SNOW BY 06Z TUESDAY
NIGHT. A GOOD BIT OF INSTABILITY WILL BE PRESENT WITH THIS FRONT AND
THE SNOW SHOWERS MAY BE HEAVY AT TIMES BUT WITH THE WARM DAYS WE HAVE
HAD...ACCUMULATIONS SHOULD BE LITTLE IF ANY AND WILL KEEP A COUPLE
TENTHS OF SNOW IN THE NORTHWEST COUNTIES. AT LEAST BY THE END OF THE
SHORT TERM FORECAST PERIOD ENDING 12Z WEDNESDAY...THIS IS ALL THE
SNOW EXPECTED RIGHT NOW. DUE TO THE GOOD INSTABILITY AND UP SLOPE
COMPONENT AVAILABLE...WILL DECIDE TO HIGHLIGHT THIS EVENT WITH AN SPS
FOR NOW...AS A WSW MAY BE NEEDED IN A FEW MORE FORECAST PERIODS.
WITH THE CONTINUED WARM SOUTHERLY FLOW...TEMPERATURES WILL REMAIN 5
TO 10 DEGREES ABOVE NORMAL THROUGH TONIGHT AND INTO TUESDAY. THE
APPROACHING FRONT TUESDAY NIGHT WILL BRING TEMPS BACK TO NORMAL
VALUES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 347 PM EST MON JAN 13 2014
MODELS START OUT IN GOOD AGREEMENT WITH A LONG WAVE OVER THE EASTERN
TWO THIRDS OF THE US. THERE IS A SHORT WAVE CENTERED OVER WISCONSIN
WHICH IS DRIVING A FRONTAL SYSTEM OUT AHEAD OF IT. ON TUESDAY NIGHT
THIS FRONT WILL MOVE THROUGH THE AREA AND THAT WILL BE FOLLOWED BY A
SURFACE TROUGH ASSOCIATED WITH THE SHORT WAVE. THIS TROUGH WILL MOVE
ACROSS THE AREA ON WEDNESDAY. BETWEEN THESE TWO SYSTEMS...THEY WILL
BE ABLE TO DROP AROUND AN INCH OF SNOW WITH UPPER ELEVATIONS MAYBE
GETTING TWO TO THREE INCHES. LOOK FOR A LULL ON THURSDAY INTO
THURSDAY NIGHT BEFORE ANOTHER COLD FRONT ARRIVES WITH ANOTHER
POTENTIAL FOR LIGHT SNOW THURSDAY NIGHT INTO FRIDAY. A CLIPPER WILL
MOVE NORTHEAST OF THE AREA...HOWEVER THE BOTTOM EDGE MAY SKIRT THE
FAR EASTERN PORTION OF THE FORECAST AREA AND BRING A SKIFF OF SNOW.
THE NEXT SYSTEM IS NOT EXPECTED TO MOVE ACROSS THE AREA UNTIL MONDAY
NIGHT. MODEL TIMING STARTS TO DIVERGE BY THE END OF THE PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 646 PM EST MON JAN 13 2014
RAIN SHOWERS CONTINUE ACROSS EASTERN KY JUST AHEAD OF AN APPROACHING
COLD FRONT. THIS IS CAUSING SOME FLUCTUATION BETWEEN VFR AND MVFR
CONDITIONS. WENT AHEAD AND FORECAST FOR THE WORST CASE SCENARIO DUE
TO THIS FLUCTUATION. AS THE NIGHT CONTINUES...RAIN SHOULD TAPER OFF
FROM WEST TO EAST. HOWEVER...THE UNCERTAINTY STILL LIES AS TO WHETHER
FOG OR LOW STRATUS WILL DEVELOP AS DRY AIR FILTERS IN ALOFT AFTER THE
FRONTAL PASSAGE. IF SOME OF THE RESIDUAL MOISTURE BECOMES TRAPPED
NEAR THE SURFACE...GUIDANCE IS SHOWING A GOOD INDICATION OF MVFR TO
POSSIBLY IFR CONDITIONS DEVELOPING FOR THE LATTER PART OF THE NIGHT.
IFR CIGS ARE ALREADY BEING OBSERVED JUST UPSTREAM.
EXPECT SKIES TO CLEAR OUT IN THE MORNING AS A BRIEF AREA OF HIGH
PRESSURE MOVES IN TOMORROW. A TIGHT PRESSURE GRADIENT BETWEEN
SYSTEMS...AND DECENT MIXING...WILL BE ENOUGH TO PRODUCE SOME HIGHER
WIND GUSTS ACROSS THE REGION. UNFORTUNATELY THIS HIGH PRESSURE WILL
BE SHORT LIVED...AS THE NEXT SYSTEM TO IMPACT THE AREA BRINGS THE
RETURN OF HIGH CLOUDS BY THE END OF THE TAF PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...SHALLENBERGER
LONG TERM...JJ
AVIATION...JMW
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1226 AM EST Sun Jan 12 2014
...Updated Aviation Discussion...
...Forecast Update...
Issued at 940 PM EST Sat Jan 11 2014
Updated the forecast to tweak sky cover, temps, and dewpts. Also
removed patchy fog from south central KY. Observations revealed a
sfc trough over central IL/central IN moving southeast along with an
upper level shortwave on the back side of an upper trough which was
exiting the region. Latest RAP and gridded LAMP guidance indicates
we`ll see low clouds over southern Indiana as well as north central
and east central KY late tonight as these features pass through the
area. Tweaked skies grids to match the latest high-res models.
Took patchy fog out of south central KY since it looks like the
atmosphere will remain too mixy with the trough and shortwave
passing through and slightly drier air will advect in behind the
trough. Most high-res models agree, but the 0Z NAM does not.
Therefore, will need to keep an eye on things overnight in case the
NAM soln is correct.
Issued at 645 PM EST Sat Jan 11 2014
Did a quick forecast update to refresh temps/dewpts and adjust sky
cover some. Low clouds are making quicker progress eastward than
previously forecast. Still looks like we`ll see low clouds
re-enforced late tonight over southeast Indiana and portions of
north and east central KY late tonight as a final shortwave dives
down on the back side of the upper trough exiting the region.
.SHORT TERM (Now through Sunday Night)...
Issued at 245 PM EST Sat Jan 11 2014
The cold front has moved through the region this afternoon and
temperatures have fallen into the 40s with gusty westerly winds. For
tonight the upper level trough will swing across the area. Models do
show a shallow layer of moisture will remain, with perhaps enough
for light drizzle tonight across far northern portions of the
forecast area, though certainty for this is not high. For now just
have higher cloud cover across the northern portions of the area.
The other question will be the potential for some patchy fog across
south central Kentucky where clouds do clear out. This will be
highly dependent on cloud cover and winds. Temperatures tonight will
fall to near or just below freezing.
For tomorrow a progressive upper level and surface ridge will scoot
across the lower Ohio Valley. This will bring mostly sunny skies and
temperatures rising into the upper 40s to lower 50s. Clouds will be
on the increase tomorrow night as the next system begins to approach
the area, though we should stay dry overnight. Tempertures will fall
into the upper 30s to lower 40s.
.LONG TERM (Monday through Saturday)...
Issued at 255 PM EST Sat Jan 11 2014
Progressive but still somewhat amplified pattern will evolve into a
mean eastern CONUS trough by the end of the week, with an overall
trend back to below-normal temps.
The first in a series of disturbances will move through the Ohio
Valley late Monday, with a southern stream wave as the main player.
Some uncertainty over the degree of phasing with the northern
stream, but it is worth noting the GFS and ECMWF are in decent
agreement that phasing will occur, with the less phased NAM as an
outlier. Therefore will continue to favor the wetter solution with
likely POPs in south-central and east-central Kentucky, tapering
down to 30-40% over southern Indiana. Temps will be easily warm
enough to keep this all rain, but there is no instability to support
thunder with this system. Cold air will mainly be chasing the
moisture out of here Monday night, but we could see a changeover to
snow before the precip ends, mainly south of the Bluegrass region.
Tuesday looks to at least start mild and dry ahead of the next
disturbance, which will dive SE out of Canada. POPs will ramp up
late in the day, and we could see falling afternoon temps given what
should be a decent temp/dewpoint spread. Went with a rain/snow mix
to start, but will carry all snow Tuesday night as the cold air
spills in. Best chance for snow will be in southern Indiana late
Tuesday night, and the Bluegrass region during the day on Wednesday.
Could see a quick half inch of snow in these areas, and temps will
struggle to crack 30 degrees. This remains a lower probability event
as the latest Euro keeps the best forcing for a deformation band
cleanly to our north.
Quick rebound in temps Thursday under strong shortwave ridging, and
then another shot of cold air arrives on Friday with a deep upper
trof diving into the Great Lakes. Continuing to lean on the colder
ECMWF temps, even as this run starts to look a bit more progressive.
The 12Z ECMWF is still closer to its predecessors than to the much
more progressive GFS. High confidence that we will be near or below
freezing for highs on Friday, but there is some doubt as to how long
the cold air will stick around in the Ohio Valley. In this pattern
it`s difficult to rule out a few flurries, especially in the north
and east. However, moisture appears to be limited, so will not carry
flurries just yet. Coldest night will be Friday night. At this point
the cold air mass does not appear to pack the same punch as the cold
outbreak earlier this week, but it still bears watching for
unseasonable cold.
&&
.AVIATION (06Z TAF Update)...
Updated at 1225 AM EST Sun Jan 12 2014
Quiet TAF period in store as surface high pressure and weak upper
ridge dominate. Do have some concern about solid MVFR ceilings
working south toward SDF/LEX toward dawn, but higher res models have
a good handle currently and it looks like the ceiling should remain
just north of SDF. LEX may have a few hours just after dawn of
ceilings below fuel alternate. Otherwise, expect general winds
between WSW and S between 5 and 10 mph. Mostly sunny skies should
prevail for much of the afternoon.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Updates........AMS
Short Term.....EER
Long Term......RAS
Aviation.......BJS
AREA FORECAST DISCUSSION
NWS CARIBOU ME
954 PM EST MON JAN 13 2014
.SYNOPSIS...
A FRONTAL BOUNDARY WILL SLIDE ACROSS THE REGION LATER TONIGHT
INTO TUESDAY. LOW PRESSURE WILL BE MOVING UP ALONG THE FRONT
ACROSS EASTERN MAINE TUESDAY NIGHT INTO WEDNESDAY MORNING.&&
.NEAR TERM /THROUGH TUESDAY/...
UPDATE 2155 EST: A BROKEN TO OVERCAST MID CLOUD DECK HAS MOVED
OVER THE STATE. WSR-88D SHOWS LIGHT RETURNS...BUT NO REPORTS OF
PRECIP SO FAR AND THERE IS STILL A 10+ TEMP/DEWPOINT SPREAD AT
OBSERVATION SITES. THE LATEST HRRR RUN HAS PRECIP MOVING IN AROUND
3 AM. NO CHANGES MADE TO THE FORECAST.
UPDATE 1845 EST: IR SATELLITE IMAGERY SHOWED CLOUDS ON THE
INCREASE ACROSS THE STATE WITH TEMPS IN THE 30S. NO CHANGES MADE
TO THE EXISTING FORECAST.
CLOUDS WILL CONTINUE TO THICKEN OVERNIGHT IN ADVANCE OF LOW PRESSURE
MOVING NORTHEAST ACROSS WESTERN QUEBEC PROVINCE. SOME LIGHT
PRECIPITATION IN RESPONSE TO WARM ADVECTION IS EXPECTED TO DEVELOP
ACROSS NORTHERN AND WESTERN SECTIONS PRIMARILY AFTER MIDNIGHT.
PRECIPITATION THAT DEVELOPS TONIGHT WILL START MAINLY IN THE FORM OF
SOME LIGHT FREEZING RAIN OR FREEZING RAIN/SLEET MIX. WILL CONTINUE
WITH THE CURRENT FREEZING RAIN ADVISORIES FOR THE NORTHWEST ZONES
AND NORTHWEST MAINE ALTHOUGH WE ARE CERTAINLY NOT EXPECTING THIS
EVENT TO BE OF THE SAME MAGNITUDE OF THIS PAST WEEKENDS SINCE
TEMPERATURES HAVE MODERATED SUBSTANTIALLY OVER THE PAST COUPLE OF
DAYS. NEVERTHELESS THERE WILL BE SOME SLICK SPOTS WHERE FREEZING
RAIN OCCURS ESPECIALLY ON SECONDARY ROADS THAT MAY STILL HAVE SOME
ICE COVER. TEMPERATURES ARE NOT EXPECTED TO FALL ALL THAT MUCH
THIS EVENING WITH CLOUDS ON THE INCREASE AND THEN THEY SHOULD
SLOWLY MODERATE OVERNIGHT.
THERE MAY STILL BE SOME POCKETS OF FREEZING RAIN ACROSS THE COLDER
VALLEYS OF NORTHWEST MAINE AND THE ST JOHN VALLEY FIRST THING TUESDAY
MORNING OTHERWISE ALL AREAS SHOULD RISE ABOVE FREEZING FOR ALL RAIN
BY LATER TUESDAY MORNING. A WEAK WAVE OF LOW PRESSURE IS EXPECTED TO
DEVELOP ALONG THE APPROACHING COLD FRONT AND THIS SHOULD RESULT IN A
ROUND OF STEADIER/HEAVIER RAINFALL ESPECIALLY ACROSS EASTERN MAINE.
WITH TEMPERATURES EXPECTED TO BE WELL ABOVE FREEZING AND SOME MORE
RAIN EXPECTED WILL HAVE TO CONTINUE TO MONITOR THE WATERWAYS FOR ICE
MOVEMENT. PLEASE REFER TO THE HYDROLOGY SECTION BELOW FOR MORE
DETAILED INFORMATION.&&
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
WEAK LOW PRESSURE DEVELOPS OVER NEAR THE SOUTHWEST TIP OF NOVA SCOTIA
TUESDAY EVENING AND RACES OFF TO THE EAST. AT THIS TIME IT APPEARS
THIS SYSTEM WILL BE GETTING ORGANIZED TOO LATE TO HAVE MUCH OF AN
IMPACT ON OUR AREA EXCEPT FOR SOME LINGERING LIGHT RAIN OR LIGHT
SNOW OVER EXTREME EASTERN MAINE IN THE EVENING.
MILD HIGH PRESSURE WILL BRIEFLY MOVE OVERHEAD EARLY WEDNESDAY. FOR
WEDNESDAY NIGHT INTO THURSDAY, THERE IS A LOT OF UNCERTAINTY. THE
MAIN UPPER LEVEL TROUGH OFF TO OUR WEST WILL WEAKEN/FALL APART AS
IT APPROACHES THE REGION, WITH MUCH OF THE ENERGY BEING
TRANSFERRED TO A DEVELOPING LOW OFF CAPE COD THURSDAY. LOTS OF
UNCERTAINTY AS TO HOW THIS PLAYS OUT. MANY GFS ENSEMBLE MEMBERS
BRING THE LOW UP THE BAY OF FUNDY AS A ROBUST SYSTEM WHICH WOULD
RESULT IN A DECENT RAIN/SNOW EVENT, BUT OPERATIONAL GFS AND MOST
OTHER MODELS DO NOT. WILL PLAY IT SAFE FOR THURSDAY AND THURSDAY
NIGHT FOR NOW AND NOT HIT IT VERY HARD.
TEMPERATURES TUESDAY NIGHT THROUGH THURSDAY WILL REMAIN WELL ABOVE
AVERAGE.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
FAIRLY UNSETTLED PATTERN DOES CONTINUE TO BE THE STORY FOR MUCH OF
THE LONG TERM PERIOD. THE LATEST 12Z RUN OF THE GFS DOES REFLECT
MORE QPF FOR THURSDAY NIGHT AS IT INDICATES PHASING IN THE UPPER
LEVEL ENERGY. THIS RUN HAS BEEN THE MOST ROBUST AND THERE IS ALSO
SUPPORT FOR A COASTAL LOW DEVELOPING IN THE 12Z GFS ENSEMBLE MEAN.
HOWEVER THE 00Z ECMWF AND 12Z CMC DO NOT SUPPORT THIS SOLUTION AND
KEEPS THIS FEATURE MOSTLY SOUTH AND EAST. IN CONCLUSION THIS
SYSTEM WILL HAVE TO BE MONITORED IN SUBSEQUENT RUNS OF THE LONG
RANGE GUIDANCE. THIS LOW IS EXPECTED TO TRACK EAST OF THE REGION
BY FRIDAY.
THE NEXT FEATURE OF INTEREST IS A HIGH AMPLITUDE TROUGH SETTING UP
FROM THE GREAT LAKES DOWN TO THE TENNESSEE VALLEY FRIDAY
AFTERNOON. THERE ARE SOME DIFFERENCES IN WHERE AND HOW STRONG THE
ASSOCIATED SURFACE LOW WILL BE. ALTHOUGH BOTH MODELS INDICATE THAT
AS ENERGY/POSITIVE VORTICITY ADVECTS AROUND THE BASE OF THE TROUGH
AND WILL AID TO DEEPEN A LOW ACROSS THE NE. THE 12Z GFS BRINGS THE
CENTER OF LOW PRESSURE NE ACROSS DOWNEAST MAINE BY SATURDAY
MORNING. LOOKING A PREVIOUS RUNS THE MODEL AND OVERALL IT HAS
CONTINUED TO TREND WEST WITH THE LOW TRACK. THE SETUP WOULD BRING
MIXING TO DOWNEAST AND COASTAL LOCATIONS WHILE SNOW MORE LIKELY
ACROSS THE NORTH AND WEST. THE 00Z ECMWF IS SLOWER AND BRINGS THE
LOW UP THROUGH THE STATE. THIS TRACK WOULD BRING MIXING TO CENTRAL
LOCATIONS SOUTH. THE 12Z CMC KEEPS THE LOW SOUTH OF THE REGION.
RIGHT NOW WILL PLAN TO GO WITH BLEND APPROACH WITH UNCERTAINTY
STILL LOOMING AROUND THIS SYSTEM. HOWEVER DOES LOOK LIKE WINDY
AND COOLER CONDITIONS MOVE IN FOR SATURDAY NIGHT INTO SUNDAY.
ANOTHER LOW WILL PROGRESS INTO THE REGION LATER SUNDAY INTO MONDAY
DEPENDING ON GUIDANCE USED. ALTHOUGH THE QPF LOOKS TO BE QUITE
LIGHT WITH THIS SYSTEM. TEMPERATURES WILL BE GENERALLY ABOVE TO
NEAR NORMAL TILL AROUND FRIDAY THEN TEMPERATURES FALL TO NEAR AND
BELOW REST OF THE PERIOD.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
NEAR TERM: VFR CONDITIONS THIS EVENING WILL GIVE WAY TO MVFR AFTER
MIDNIGHT. SOME LIGHT FZRA MAY IMPACT KFVE/KCAR MAINLY AFTER
MIDNIGHT. CONDITIONS ARE THEN EXPECTED TO DETERIORATE TO IFR AT ALL
THE TERMINALS TUESDAY IN MAINLY PLAIN RAIN/LOW CIGS/AREAS OF FOG.
SHORT TERM: IFR CONDITIONS WILL IMPROVE TO VFR LATE TUESDAY NIGHT
AS THE SYSTEM MOVES OFF TO THE EAST. GENERALLY VFR FOR WEDNESDAY.
MVFR/IFR POSSIBLE ON THURSDAY DEPENDING ON HOW THE NEXT SYSTEM
EVOLVES.
&&
.MARINE...
NEAR TERM: SMALL CRAFT ADVISORY CONDITIONS WILL CONTINUE THROUGH
MOST OF TUESDAY.
SHORT TERM:
WINDS WILL GENERALLY BE BELOW SMALL CRAFT LEVELS TUESDAY NIGHT THROUGH
THURSDAY. HOWEVER, DEPENDING ON HOW THINGS EVOLVE WITH AN UPCOMING
POTENTIAL COASTAL LOW, THERE COULD BE SMALL CRAFT CONDITIONS
THURSDAY. SEAS WILL GENERALLY BE JUST ABOVE SMALL CRAFT LEVELS
THROUGH THURSDAY.
&&
.HYDROLOGY...
SOME MINOR RISES AND ICE MOVEMENT WAS NOTED THIS AFTERNOON ON SOME
OF THE AREA RIVERS BUT ALL WERE WELL BELOW FLOOD STAGE. THE
COMBINATION OF ADDITIONAL RAINFALL LATE TONIGHT AND TUESDAY IN
CONJUNCTION WITH TEMPERATURES ABOVE FREEZING MAY RESULT IN
ADDITIONAL ICE MOVEMENT...ESPECIALLY ACROSS THE CENTRAL AND DOWNEAST
RIVERS. RAINFALL AMOUNTS THROUGH THE DAY TUESDAY ARE EXPECTED TO
RANGE FROM ONE TO TWO TENTHS ACROSS NORTHERN AREAS AND A QUARTER OF
AN INCH TO A THIRD OF AN INCH ACROSS CENTRAL AND DOWNEAST AREAS.
HOWEVER...THERE COULD BE SOME AMOUNTS APPROACHING A HALF AN INCH
ACROSS WASHINGTON COUNTY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...FREEZING RAIN ADVISORY UNTIL 10 AM EST TUESDAY FOR MEZ001>004-
010.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST TUESDAY FOR ANZ050>052.
&&
$$
NEAR TERM...DUDA/OKULSKI
SHORT TERM...FOISY
LONG TERM...JORDAN
AVIATION...DUDA/OKULSKI/FOISY
MARINE...DUDA/OKULSKI/FOISY
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS GRAY ME
635 PM EST MON JAN 13 2014
.SYNOPSIS...
A SERIES OF WEAK LOW PRESSURE SYSTEMS WILL TRACK NORTHEAST ALONG
THE EASTERN SEABOARD THIS WEEK. EACH OF THESE LOWS PROVIDE A ROUND
OF MAINLY LIGHT PRECIPITATION...AND EACH ONE WILL ALSO BRING
INCREASINGLY COLDER AIR. THE FIRST SYSTEM MOVES IN TONIGHT...AND
WILL LIKELY START AS FREEZING RAIN INLAND...BEFORE CHANGING TO
RAIN ON TUESDAY. ANOTHER SYSTEM MAY BRUSH BY NEW ENGLAND...JUST
OFF THE COAST ON WEDNESDAY. WE WILL SEE ANOTHER ONE DAY BREAK ON
FRIDAY...BEFORE ANOTHER SYSTEM MOVES IN FRIDAY NIGHT AND SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
UPDATED TO INPUT LATEST OBSERVED DATA RESULTING IN A FEW TWEAKS TO
THE FCST. OVERALL FCST REMAINS THE SAME.
PREVIOUS DISCUSSION...
WILL CONTINUE FREEZING RAIN ADVISORIES FOR TONIGHT...HOWEVER WE
HAVE BACKED OFF ON THE TIMING BY A COUPLE HOURS. LATEST HRRR MODEL
RUN CONTINUES TO SHOW THE PRECIP ARRIVING IN NORTHERN PORTIONS OF
OUR AREA AROUND OR SHORTLY AFTER MIDNIGHT. HAVE ALSO ADDED
PORTIONS OF SOMERSET COUNTY TO THE ADVISORY AREA...AS WELL AS
SOUTHERN CARROLL AND SOUTHERN GRAFTON COUNTIES.
THESE ADVISORIES WILL NEED TO BE MONITORED AS DEW POINTS STILL
REMAIN RELATIVELY LOW IN THE AREA. THERE IS THE POSSIBILITY THAT
THIS ADVISORY AREA MAY NEED TO BE EXPANDED OVERNIGHT.
USED DIURNAL FROM MOS ONCE AGAIN FOR TONIGHT. THERE COULD BE A FEW
LOCATIONS WITH SLEET...BUT THIS WILL PRIMARILY BE A FREEZING RAIN
OR RAIN EVENT...DEPENDING ON YOUR LOCATION.
HAVE CONTINUED MENTION OF AREAS OF DENSE FOG. WARM...MOIST AIR
OVER THE SNOWPACK WILL LEAD TO PLENTY OF LOW LEVEL MOISTURE IN THE
REGION. IF THE DENSE FOG DEVELOP...A DENSE FOG ADVISORY MAY BE NEEDED.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
PRECIP CONTINUES TUESDAY MORNING AND GRADUALLY CHANGES TO ALL
RAIN. ADVISORIES WILL CONTINUE UNTIL THAT TIME OVER NORTHERN
AREAS. OTHERWISE...THE FRONTAL SYSTEM WILL GRADUALLY SHIFT DURING
THE AFTERNOON AND EVENING HOURS...ALLOWING FOR A BRIEF BREAK IN
THE CLOUD COVER AND PRECIP PRIOR TO THE NEXT SYSTEM MOVING IN FROM
THE WEST.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
WE BEGIN THE PERIOD WITH A DEEP TROUGH OVER THE EASTERN HALF OF
THE CONUS WITH AXIS CENTERED OVER THE WESTERN GREAT LAKES AND
MISSISSIPPI VALLEY. A SERIES OF IMPULSES WILL DIVE SOUTHEAST INTO
THE UPPER TROUGH AND KEEP OUR WEATHER MILD BUT UNSETTLED FOR THE
SECOND HALF OF THE WORKWEEK. WHILE MODELS AGREE THE UPPER TROUGH
WILL EVENTUALLY SLIDE EAST AND DELIVER MUCH COLDER AIR TO THE AREA
BY THE SECOND HALF OF THE WEEKEND...THERE ARE SIGNIFICANT TIMING
DIFFERENCES WITH INDIVIDUAL IMPULSES. BY MONDAY...WE`RE LEFT WITH
A BROAD TROUGH OVER THE EASTERN TWO THIRDS OF THE CONUS AS THE
CORE OF THE COLD AIR LIFTS OUT TO OUR NORTH AND EAST. IN THE
DAILIES...A WEAK LOW WILL APPROACH FROM THE GREAT LAKES LATE
WEDNESDAY THEN TRACK DOWN THE SAINT LAWRENCE VALLEY WEDNESDAY
NIGHT. LOW PRESSURE WILL DEVELOP OFF THE ATLANTIC COAST ON
THURSDAY THEN PASS WELL TO OUR SOUTH AND EAST THURSDAY NIGHT
FOLLOWED BY A WEAK RIDGE OF HIGH PRESSURE EARLY FRIDAY. ANOTHER
LOW WILL CROSS THE REGION FRIDAY NIGHT INTO SATURDAY FOLLOWED BY
MUCH COLDER AIR FOR THE SECOND HALF OF THE HOLIDAY WEEKEND.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH TUESDAY NIGHT/...CONDITIONS DETERIORATING TO
LIFR AS AREAS OF RAIN AND DENSE FOG DEVELOP LATER TNGT WITH
FREEZING RAIN NRN AREAS...IMPACTING MOSTLY JUST HIE TAF.
CONDITIONS SLOWLY IMPROVING LATE TUESDAY OR TUESDAY NGT.
LONG TERM...
THU...SCT MVFR POSSIBLE IN RAIN OR SNOW SHOWERS.
FRI NIGHT - SAT...AREAS OF MVFR POSSIBLE IN RAIN OR SNOW.
NW SFC WND GUSTING TO 25 KT PSBL SAT.
&&
.MARINE...
SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...WILL UPDATE TO INPUT
LATEST OBSERVED DATA WITH SOME MINOR CHANGES TNGT. OVERALL FCST
REMAINS THE SAME WITH SCA UP FOR ALL ZONES. SCAS ARE GOOD THROUGH
TUESDAY...WHICH MAY NEED TO BE EXTENDED IN MOST AREAS TUESDAY
NIGHT.
LONG TERM...
THU NIGHT - FRI AM...GALE FORCE WINDS ARE POSSIBLE.
SAT...SMALL CRAFT CONDITIONS ARE POSSIBLE.
&&
.HYDROLOGY...
A FLOOD WARNING REMAINS UP FOR THE SUGAR RIVER AT WEST CLAREMONT
DUE TO AN ICE JAM. THERE ARE OTHER ICE JAMS BUT NO FLOODING
EXPECTED OR OCCURRING AT THIS TIME.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...FREEZING RAIN ADVISORY FROM MIDNIGHT TONIGHT TO NOON EST
TUESDAY FOR MEZ007>009-012>014.
NH...FREEZING RAIN ADVISORY FROM MIDNIGHT TONIGHT TO NOON EST
TUESDAY FOR NHZ001>006.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST TUESDAY FOR ANZ150>154.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
408 PM EST MON JAN 13 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 405 PM EST MON JAN 13 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD MID/UPPER LEVEL TROUGH
FROM HUDSON BAY THROUGH THE CNTRL CONUS. A SHORTWAVE TROUGH WAS
MOVING THROUGH NRN ONTARIO BRINGING LIGHT SNOW TO LOCATIONS NORTH OF
LAKE SUPERIOR. A CLIPPER SHRTWV INTO NRN MONTANA WAS MOVING SE INTO
THE DAKOTAS. AT THE SFC...COLDER AIR WAS MOVING INTO UPPER MI
BEHIND A COLD FRONT EXTENDING FROM NRN ONTARIO THROUGH ERN UPPER MI
INTO WRN LOWER MI. A SECONDARY COLD FRONT STRETCHED FROM THE NORTH
END OF LAKE SUPERIOR INTO NRN MN. WITH 850 MB TEMPS ONLY TO AROUND
-13C OVER WRN LAKE SUPERIOR AND DRY AIR MOVING IN FROM NE
MN...LITTLE/NO LES HAS DEVELOPED INTO NW UPPER MI THROUGH 20Z.
TONIGHT...ADDITIONAL CAA DROPPING 850 MB TEMPS TO AROUND -15C SHOULD
BE ENOUGH TO BRING SOME LES FOR LOCATIONS FAVORED BY WRLY FLOW THIS
EVENING. AS WINDS VEER N TO NW OVERNIGHT...ANY LES WILL SPREAD INTO
THE REST OF WRN UPPETHE R MI AND FOR LOCATIONS FROM P53
EASTWARD. HOWEVER...THE MARGINAL INSTABILITY AND INVERSION HEIGHTS
ONLY TO 4K FT WILL LIMIT INTENSITY AND KEEP ANY ACCUMULATIONS BELOW
AN INCH.
TUESDAY...THE MODELS WERE IN RELATIVELY GOOD AGREEMENT WITH THE
CLIPPER SHRTWV MOVING TO NEAR THE SRN END OF LAKE MI BY 00Z/WED. THE
ASSOCIATED SFC LOW AND STRONGEST 700-300 QVECTOR CONV AND MID LEVEL
FGEN IS EXPECTED TO REMAIN SOUTH OF UPPER MI. HOWEVER...THE STRONGER
DYNAMICS WILL STILL BE CLOSE ENOUGH TO GRAZE THE SRN PORTION OF THE
CWA NEAR MNM WITH SEVERAL INCHES OF SNOW. QPF AMOUNTS TO AROUND 0.15
INCH WITH SLR VALUES NEAR 18/1 WOULD SUPPORT SNOW AMOUNTS TO NEAR 3
INCHES. CONFIDENCE IN SNOWFALL AMOUNTS IS STILL LIMITED SINCE THE
AREA IS ON THE NRN EDGE OF THE SIGNIFCANT QPF FCST. LES INTO THE N
CNTRL CWA NEAR P53 IS ALSO EXPECTED TO INCREASE WHERE THE CONVERGENT
NRLY FLOW IS FOCUSED. OVER THE WEST...THE LOW INVERSION HEIGHTS AND
MORE ACYC FLOW WILL ALSO REDUCE LES CHANCES/AMOUNTS.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 405 PM EST MON JAN 13 2014
LARGE SCALE PATTERN THROUGH THE EXTENDED INDICATES A RIDGE OVER
THE WESTERN CONUS AND WESTERN CANADA WHILE TROUGHING DOMINATES
MUCH OF THE EASTERN CONUS...INCLUDING THE GREAT LAKES. STRONGEST
WAVE WITHIN THE TROUGH CROSSES THE UPPER GREAT LAKES WEDNESDAY NIGHT
THROUGH FRIDAY. DAYTIME HIGHS WILL END UP BLO NORMAL FOR MUCH OF
THE TIME...BUT NOT BY THAT MUCH. WARMEST DAY APPEARS TO BE ON
THURSDAY AHEAD OF STRONGER COLD FRONT. WARMING TREND DEVELOPS AT
THE VERY END OF THE EXTENDED...THOUGH HOW QUICK THAT OCCURS IS
STILL UNCERTAIN AS ECMWF/GFS SHOW LIMITED CONSISTENCY IN HOW FAST
TO EXIT THE LARGER SCALE TROUGH AT THAT TIME RANGE.
TUESDAY NIGHT INTO WEDNESDAY...LAKE EFFECT NEAR LK SUPERIOR MAINLY
FOR AREAS FAVORED BY NNW WINDS. IN THE LARGE SCALE...HIGH PRESSURE
RESULTS IN NEUTRAL TO ANTICYCLONIC FLOW AND INVERSION HEIGHTS TO
5KFT. CONVERGENCE STRONGEST OVER ALGER AND NORTHERN SCHOOLCRAFT
AND MAJORITY OF CONVECTIVE LAYER WILL BE WITHIN DGZ. ADVY LEVEL SNOW
COULD OCCUR BUT WOULD PROBABLY BE SPREAD FM LATE AFTN ON TUESDAY
THROUGH MIDDAY ON WEDNESDAY. LIKELY WILL BE LAKE EFFECT OVER WESTERN
SNOWBELTS TOO...BUT SINCE THAT AREA IS FARTHER INTO AFFECTS OF SFC
HIGH...INTENSITY/ACCUMS SHOULD BE MINIMAL. LAKE EFFECT SHOULD LINGER
OVER ALGER COUNTY UNTIL LATE WEDNESDAY AFTN ONCE WINDS IN THE BLYR
FINALLY BECOME WEST OR SOUTHWEST AS SFC-H85 RIDGE CROSSES UPPER GREAT
LAKES. EVEN WITH WARMING AT H85...COOLER AIR LINGERS BLO...SO TEMPS
ON WEDNESDAY WILL STAY SIMILAR TO READINGS ON TUESDAY MAINLY IN THE
TEENS.
WEDNESDAY NIGHT INTO THURSDAY...ATTN IS ON STRONG SHORTWAVE DIGGING
FM SOUTHERN PORTIONS OF SASKATCHEWAN AND MANITOBA TO THE NORTHERN
PLAINS BY EARLY WEDNESDAY EVENING. SHORTWAVE DIGS INTO UPPER
MISSISSIPPI RIVER VALLEY BY THURSDAY MORNING WHILE ASSOCIATED SFC
LOW MOVES VCNTY OF WESTERN LK SUPERIOR. DECENT AGREEMENT THAT H85-H7
WARM AND MOIST ADVECTION/ISENTROPIC ASCENT 280-285K WILL SUPPORT
SWATH OF LGT SNOW ACROSS MUCH OF CWA. MIXING RATIOS AT H7 ONLY NEAR
1.5G/KG SO OVERALL THE SYNOPTIC SNOW WILL BE LIMITED TO 1-3 INCHES.
COUPLE OF ITEMS TO NOTE THOUGH. FIRST IS POTENTIAL FOR LAKE ENHANCED
SNOW DOWNWIND OF LAKE MICHIGAN. SSW WINDS IN BLYR WITH H85 TEMPS
AROUND -12C ON WEDNESDAY NIGHT RESULT IN THIS POTENTIAL. AS IT LOOKS
NOW...AREAS MAINLY TO EAST OF KISQ AND TOWARD KERY WOULD BE FAVORED
03Z-15Z THURSDAY. SLR/S PROBABLY IN THE 13-16:1 RANGE AS GFS
SOUNDINGS SHOW ISOTHERMAL LAYER FM H9 TO H75 AROUND -13C. SEEMS
THAT ADVY SNOWS COULD OCCUR IN THIS TYPE OF SETUP. SECOND ISSUE IS
POTENTIAL FOR GUSTY WINDS OVER THE CWA AS THE SNOW IS
OCCURRING...ADDING A BIT MORE OF AN IMPACT TO THE OTHERWISE LGT SNOW
ACCUMS. GFS AND ECMWF BOTH POINT TO WINDS GUSTING 25-30 KTS AS THE
SNOW OCCURS WITH STRONG PRESSURE FALLS SPREADING ACROSS LK
SUPERIOR...ESPECIALLY WEDNESDAY EVENING...BEFORE THE LOW MAY START
TO WEAKEN LATER WEDNESDAY NIGHT. PRETTY CERTAIN THAT SOME HEADLINES
MAY BE NEEDED...WITH THE HIGHEST CERTAINTY COMING OVER THE SE ZONES
DUE TO LAKE ENHANCEMENT AND BLSN CLOSER TO LK MICHIGAN SHORE. IF
STRONGER FORCING WAS PRESENT FOR LONGER DURATION AND AIRMASS IN THE
LOW-LEVEL SSW FLOW WAS COLDER...COULD EVEN SEE NEED FOR WARNING. NOT
SURE IF HEADLINES WILL BE NEEDED ELSEWHERE SINCE SNOW AMOUNTS ARE ON
LOWER SIDE AND SINCE ONLY EXPECTING MARGINALLY STRONG WIND GUSTS (30
KTS IN BLYR VERSUS 50 KTS). CANNOT COMPLETELY RULE THAT OUT THOUGH.
BY DAYBREAK THURSDAY AND BEYOND...GFS/ECMWF/GEM-NH NOT SURE HOW
THINGS EVOLVE INTO THURSDAY NIGHT. LOOKS LIKE PREVIOUS RUNS OF ECMWF
AND GEM-NH WERE STRONGER WITH THE SFC LOW WHILE THE 12Z GFS TRENDED
STRONGER. GFS DOES ALSO SHOW THE LOW EVENTUALLY FILLING LATER ON
THURSDAY AS IT CROSSES THE REGION. UNCERTAINTY MAINLY IMPACTS THE
WIND FIELDS ON BACK SIDE OF THE LOW WHEN COLD FRONT CROSSES LK
SUPERIOR AND UPR MICHIGAN. COLD AIR ADVECTION IS STRONG BUT THE
REALLY STRONG WINDS WOULD BE MITIGATED SOME WITHOUT TIGHTER SFC
PRESSURE GRADIENT. NOTHING CERTAIN THOUGH...ESPECIALLY GIVEN MODEL
INCONSISTENCY. STRONGER SYSTEM WOULD RESULT IN MORE CONSIDERABLE
BLSN OVER EXPOSED AREAS NEAR LK SUPERIOR...MAINLY IN THE WESTERN
CWA AS MORE ICE IS BUILT UP IN THOSE AREAS CLOSER TO THE SHORE.
LAKE EFFECT THAT DEVELOPS IN WAKE OF THE COLD FRONT PROBABLY GETS
A BOOST INTO FRIDAY AS MID-LEVEL TROUGH AXIS AND H85-H7 CROSS THE
AREA. WIND DIRECTION NOT CLEAR THOUGH AS WEAKER SYSTEM AS ECMWF
SHOWS RESULTS IN NW FLOW LAKE EFFECT WHILE GFS AND TO SOME EXTENT
THE GEM-NH WOULD IMPACT N/NE FLOW AREAS THURSDAY NIGHT THEN SWITCH
TO MORE OF A N/NW FLOW AREAS ON FRIDAY. WINDS BACKING LATER FRIDAY
INTO FRIDAY NIGHT ALONG WITH TEMPS IN LOW-LEVELS WARMING SLIGHTLY
SHOULD DIMINISH LINGERING LAKE EFFECT BY SATURDAY.
REST OF EXTENDED...AS ALLUDED TO EARLIER THE FCST FOR LATE IN THE
WEEKEND INTO EARLY NEXT WEEK IS UNCERTAIN WITH HANDLING OF EXITING
OF LARGER SCALE TROUGH. 12Z ECMWF BACK TO SHOWING ONE LAST PUSH OF
CHILLY AIR LATER SUNDAY INTO MONDAY WITH H85 TEMPS BLO -20C. 00Z
ECMWF HAD THIS COLD AIR PUSH WELL TO THE NORTH...WITH TEMPS NEARING
0C AT H85 PUSHING INTO WESTERN GREAT LAKES. MEANWHILE...LATEST GFS
LOOKS LIKE 00Z ECMWF RUN FM LAST NIGHT WITH WARMING SPREADING INTO
UPR LAKES TO CLOSE NEXT WEEKEND. RAN WITH MODEL CONSENSUS FOR THE
GRIDS UNTIL TIMING/WESTERN EXTENT OF LARGER SCALE TROUGH CAN BE
WORKED OUT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1243 PM EST MON JAN 13 2014
EXPECT MVFR CONDITIONS AT IWD AND CMX WITH UPSLOPE WRLY WINDS IN THE
WAKE OF A COLD FRONT. LIGHT LAKE EFFECT SNOW SHOWERS WILL START IN
THE LATE MORNING AND LAST THROUGH THE REST OF THE FORECAST PERIOD AT
BOTH IWD AND CMX AS WINDS VEER NRLY.
LOWER CONFIDENCE WITH THE SAW FCST...WHERE MAINLY DOWNSLOPE
CONDITIONS PREVAIL UNTIL LATE TONIGHT. CIGS MAY LIFT TO LOW END VFR
TOWARD EVENING AND REMAIN THAT WAY UNTIL WINDS VEER AROUND NRLY LATE
TONIGHT AND BRING BACK MVFR CIGS AND LIGHT LAKE EFFECT SNOW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 405 PM EST MON JAN 13 2014
GUSTY WEST WINDS TO 30 KTS THROUGH THE EVENING DIMINISH TO 25 KTS ON
TUESDAY WHILE BECOMING NORTHWEST. EXPECT THE WINDS TO DIMINISH
BRIEFLY LATE TUESDAY NIGHT INTO WEDNESDAY AFTERNOON AS A HIGH
PRESSURE RIDGE CROSSES THE REGION. LOW PRESSURE CROSSING LAKE
WINNIPEG LATE WEDNESDAY AFTERNOON WILL THEN SINK ACROSS LAKE
SUPERIOR ON THURSDAY. EXPECT SW GALES OF 35-40KTS WEDNESDAY NIGHT
OVER EASTERN SECTIONS. N-NW GALES OF 35 KTS ARE POSSIBLE LATE
THURSDAY AFTERNOON THROUGH FRIDAY MORNING IN WAKE OF A COLD
FRONT FOLLOWING THE LOW. THE LOW WILL WEAKEN AS IT DRIFTS EASTWARD
INTO SOUTHERN ONTARIO THROUGH THE DAY FRIDAY...WHILE KEEPING A WEAK
TROUGH OVER LAKE SUPERIOR. HEAVY FREEZING SPRAY
WILL BE POSSIBLE THURSDAY NIGHT THROUGH FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...JLB
MARINE...JLA
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1207 PM CST SUN JAN 12 2014
.UPDATE...
ISSUED AT 854 AM CST SUN JAN 12 2014
HAVE HAD TO ISSUE A RATHER SHORT FUSE FREEZING RAIN ADVISORY IN
CENTRAL MINNESOTA FOR AREA OF LIGHT RAIN MOVING THROUGH. ALTHOUGH
MOST REPORTING LOCATIONS HAVE ONLY REPORTED PRECIP FOR 1 TO 2
HOURS...WITH TEMPERATURES RANGING FROM 28 TO 32...WE HAVE SEEN A
SIGNIFICANT AMOUNT OF TRAVEL CONCERNS DEVELOP ACROSS CENTRAL MN
WITH ICING CONDITIONS. MNDOT TRAVEL MAP HAS CATEGORIZED ROADS
ACROSS CENTRAL MN AS HAZARDOUS WITH TRAVEL NOT ADVISED...WHICH WAS
A BIG REASON FOR ISSUING THIS ADVISORY.
HOPWRF AND HRRR SHOW THIS BAND OF PRECIP LIFTING NE TOWARD
DLH...SO SEE NO NEED TO EXPAND THE FREEZING RAIN ADVISORY EAST
INTO WEST CENTRAL WI...AS ALL SHORT TERM MODELS INDICATE THAT THEY
WILL SEE NO PRECIPITATION OVER THERE. THE WEST EDGE OF THE ADVISORY
WAS SET BASED ON WHERE PRECIP IS CURRENTLY FALLING...COULD HAVE
ADDED BENSON UP THROUGH ALEXANDRIA TO THE ADVISORY...BUT RAIN
THERE IS ALREADY DONE...WITH TEMPERATURES ALREADY STARTING TO
SNEAK ABOVE FREEZING WEST OF THE ADVY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 228 AM CST SUN JAN 12 2014
LATEST WATER VAPOR IMAGERY SHOWS HIGH CLOUDS AND MOISTURE MOVING
EAST WITH THE UPPER RIDGE AXIS ACROSS THE REGION AT THE CURRENT
TIME. THIS HAS HELPED TO INCREASE THE MID-HIGH CLOUDS OVER OUR
AREA... WITH LOWER CLOUDS STILL TO THE WEST WHERE SOME PCPN IS
APPARENT ON RADAR AND SURFACE OBS. THAT PCPN IS PRIMARILY BEING
FORCED BY SOME DECENT ISENTROPIC LIFT AHEAD OF THE UPPER TROUGH...
WHICH IS LAGGING BACK WELL TO THE WEST. THE CURRENT AREA OF PCPN
WILL TRY TO HOLD TOGETHER AS IT MOVES EAST TODAY... BUT IT STILL
APPEARS THAT THE BEST CHANCE FOR PCPN WILL BE OVER THE FAR NORTHERN
PART OF THE FORECAST AREA... WHERE DEEPER MOISTURE LOOKS TO BE
PRESENT THROUGH THE DAY. HOWEVER... EVEN THERE IT DOESN/T APPEAR AS
THOUGH PCPN AMOUNTS WILL BE SUBSTANTIAL... AND IT/S POSSIBLE SOME
LOCATIONS WON/T MEASURE AT ALL... SO STILL KEPT POPS AS CHANCES
RATHER THAN LIKELY. PCPN-TYPE WITH WHATEVER OCCURS WILL BE TRICKY...
SINCE TEMPERATURES ARE ALREADY CLIMBING ABOVE FREEZING ALOFT... AS
WAS EVIDENT IN THE UPSTREAM SOUNDINGS AT 00Z WHICH SHOWED THE WARM
NOSE AROUND 900-850MB. WITH CONTINUED WARM ADVECTION THROUGH THE DAY
THAT SITUATION SHOULDN/T IMPROVE. SO... WOULD EXPECT PARTIAL TO
COMPLETE MELTING OF PCPN ALOFT... BUT SURFACE TEMPERATURES WILL TAKE
A BIT OF TIME BEFORE THEY CLIMB ABOVE FREEZING TODAY... SO THERE
STILL APPEARS TO BE A CHANCE FOR SOME SLEET AND FREEZING
RAIN/DRIZZLE THIS MORNING WITH ANY PCPN WHICH MOVES ACROSS THE
NORTHERN PORTION OF THE AREA. BUT... AS MENTIONED... WHATEVER OCCURS
SHOULD BE LIGHT. THE UPPER TROUGH CURRENTLY EVIDENT ON WATER VAPOR
OVER THE WESTERN US WILL CONTINUE TO MOVE EAST TONIGHT... AND LOOKS
TO MOVE INTO THE WESTERN PART OF OUR AREA AFTER 06Z. WE/LL SEE AN
INITIAL COLD FRONT MOVE THROUGH THIS EVENING... WHICH WON/T DO TOO
MUCH TO COOL THINGS OFF... BUT WILL SERVE TO SHIFT WINDS AROUND TO
THE WEST AND NORTHWEST... FURTHER LIMITING THE CHANCE FOR ANY
MOISTURE RETURN AHEAD OF THE UPPER TROUGH AND MORE MEANINGFUL COLD
FRONT WHICH MOVES THROUGH OVERNIGHT. THERE COULD BE SOME LIGHT PCPN
LATE TONIGHT AS THE UPPER TROUGH AND SECONDARY FRONT MOVE THROUGH...
BUT AT THIS POINT IT DOESN/T LOOK TO BE ANY MORE THAN FLURRIES... SO
DIDN/T INCLUDE ANYTHING IN THE FORECAST. THE MAIN THING WILL BE THE
PUSH OF COLDER AIR THE SYSTEM BRINGS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 228 AM CST SUN JAN 12 2014
THE EXTENDED PERIOD WILL BE MARKED WITH A TWO STORM SYSTEMS WHICH
WILL AFFECT THE UPPER MIDWEST EARLY TUESDAY...AND THEN THURSDAY.
BOTH OF THESE SYSTEMS WILL HAVE A STRONG INFLUENCE OF THICKNESS
VALUES RISING ENOUGH TO CONSIDER A MIXTURE OF SLEET/FREEZING
RAIN/RAIN IN THE FAR SW CWA. EVEN IF WE DO GET PRECIPITATION IN
THIS AREA...THE INCREASING THICKNESS VALUES AND ASSOCIATED 85/92H
TEMPS RISING TO LIMIT THE BEST FORMATION OF ICE CRYSTALS /MORE
FREEZING RAIN/DRIZZLE AND SUPERCOOLED LIQUID WATER DROPLETS/...WILL
LIMIT SNOWFALL AMTS. BEST CHC OF RECEIVING MEASURABLE
PRECIPITATION IN SW/SC MN WILL OCCUR WITH EARLY TUESDAY/S SYSTEM.
TAKING A CROSS SECTION ALONG A KOMA TO KDLH LINE INDICATES THAT
BOTH THE GFS/EC HAVE SIMILAR SCENARIO/S OF A BRIEF PERIOD OF
STRONG LIFT ARND 6Z TUESDAY IN THE DENDRITIC SNOW ZONE. FORCING IS
VERY LIMITED 6 HRS BEFORE AND AFTER THIS TIME FRAME. AS DISCUSS
WITH THICKNESS VALUES AND THE INFLUENCE OF HIGHER 92H/85H
TEMPS...SNOWFALL AMTS MAY BE LIGHTER THAN EXPECTED. EVEN WITH A 13
TO 15-1 SNOWFALL RATIO BETWEEN 00-12Z TUESDAY...SNOWFALL AMTS WILL
RANGE FROM 1" TO 2.5". ALTHOUGH MODELS HAVE BEEN MORE CONSISTENT
IN TERMS OF A SFC LOW DEVELOPING ACROSS THE DAKOTAS...AND MOVING
THIS SYSTEM RAPIDLY SE ACROSS THE MIDWEST TUESDAY AFTN...PLACEMENT
OF THE SFC LOW WILL BE CRITICAL IN TERMS OF WHERE THE HEAVIER SNOW
BANDS DEVELOP EARLY TUESDAY. BASED ON CURRENT MODELS...THE BEST
PLACEMENT AND ASSOCIATED QPF FIELD HAS A BAND OF 1.5 TO 2.5" OF
SNOWFALL FROM LONG PRAIRIE...SE TO THE NORTHERN SUBURBS OF THE
TWIN CITIES...TO RIVER FALLS WI. ANY DEVIATION OF THIS SFC
LOW...OR STRONGER INFLUX OF WARMER AIR FROM THE SW...WILL LIMIT
SNOWFALL AMTS.
THURSDAY SYSTEM LOOKS TO BE MAINLY IN THE FORM OF SNOW...BUT DUE
TO THE FAST NATURE OF THE SYSTEM AND LIMITED DEEP MOISTURE AND
LIFT...AMTS WILL BE LIGHT AND FOCUSED NE OF MPX CWA. THE MAJOR
DIFFERENCES BETWEEN TUESDAY/S AND THURSDAY/S SYSTEM IS THE
PRESSURE GRADIENT AND ASSOCIATED STRONG SFC WIND FIELD. BASED ON
THE SFC WINDS AND GUST POTENTIAL...AND IF ANY SNOW CAN BE PICK UP
FROM THE GROUND...BLIZZARD LIKE CONDS MAY DEVELOP...ESPECIALLY IN
THE TYPICAL AREAS OF WC/SW/SC MN THU/THU NIGHT. HAVE INTRODUCED
BLOWING SNOW DURING THIS TIME FRAME...BUT IF CURRENT MODEL TRENDS
HAVE THE CONTINUED SFC PRESSURE GRADIENT FIELD THE SAME...A
BLIZZARD WATCH OR SOME OTHER HIGHLIGHTED WX EVENT IS POSSIBLE.
BEHIND THIS SYSTEM...ANOTHER ARCTIC OUTBREAK WILL OCCUR...BUT NOT
AS COLD AS THE FIRST WEEK OF JANUARY. 92H/85H TEMPS ARE 10 TO 15
DEGREES WARMER THAN THE ARCTIC CORE FROM EARLIER THIS MONTH.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1207 PM CST SUN JAN 12 2014
LAST VESTIGES OF LIGHT FREEZING RAIN EXITING THE AREA JUST NORTH
AND NORTHEAST OF KSTC AS OF 18Z. JUST MID AND HIGH CLOUDS INTO THIS
EVENING. NEXT WEAK TROUGH WILL ENTER WEST CENTRAL MN AFTER 06Z.
SECONDARY COLD FRONT WILL BE ASSOCIATED WITH THIS AND MOISTURE
PROFILE SUGGESTS MVFR CEILINGS OVER MOST OF THE AREA FOR ABOUT 6
HOURS IN ANY GIVEN LOCATION. SOME FLURRIES ARE QUITE POSSIBLE.
VISIBILITIES SHOULD MOSTLY BE UNRESTRICTED...BUT THERE IS A SMALL
CHANCE OF GETTING TO 5SM FOR AN HOUR OR SO. ONCE THAT GOES
BY...STRONGER TROUGH AND SNOW WILL ARRIVE IN WEST CENTRAL MN
MONDAY AFTERNOON... JUST BEYOND THE 24 HOUR PERIOD FOR TAFS. NEXT
TAF SET WILL LIKELY REFLECT THE INCOMING SNOW.
KMSP...JUST SOME MID AND HIGH CLOUDS THROUGH MOST OF THE PERIOD.
THERE IS A SMALL CHANCE THAT LIGHT SNOW WILL BEGIN AROUND THE 30
HOUR TIME FRAME BUT IT IS MORE LIKELY TO START MONDAY EVENING AT
KMSP. ONLY OTHER MATTER IS WIND. SOUTHWEST WIND SHOULD REMAIN
AROUND 10 KNOTS FOR SEVERAL HOURS THIS AFTERNOON THEN TAPER OFF A
BIT AS GRADIENT WEAKENS. SECONDARY COLD FRONT WILL ARRIVE LATE
TONIGHT WITH AN INCREASE TO AROUND 10 KNOTS. MIGHT BE SOME GUSTS
TO 15 KNOTS BUT HAVE NOT INCLUDED THAT RIGHT NOW.
/OUTLOOK FOR KMSP/
MONDAY NIGHT...MVFR CEILINGS/VISIBILITIES EXPECTED WITH SNOW...
IFR CONDITIONS POSSIBLE. SOUTHWEST WIND 10 TO 15 KT.
TUESDAY...MVFR CEILINGS/VISIBILITIES EXPECTED WITH LIGHT SNOW
POSSIBLE IN THE MORNING...THEN BECOMING VFR. NORTHWEST WIND 15 TO
20 KT.
WEDNESDAY...VFR. NORTHWEST WIND 5 TO 10 KT BECOMING SOUTH 5 TO 10
KT.
THURSDAY...MVFR CEILINGS/VISIBILITIES POSSIBLE WITH A CHANCE OF
SNOW. WEST TO NORTHWEST WIND 15 TO 25 KT WITH GUSTS TO 30 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
UPDATE...MPG
SHORT TERM...
LONG TERM...JLT
AVIATION...TDK
AREA FORECAST DISCUSSION
NWS DULUTH MN
1204 PM CST SUN JAN 12 2014
.UPDATE...
ISSUED AT 1204 PM CST SUN JAN 12 2014
UPDATED AVIATION SECTION BELOW.
UPDATE ISSUED AT 1011 AM CST SUN JAN 12 2014
MAIN UPPER LEVEL WAVE AXIS AND EFFECTIVE SURFACE WARM FRONT LIE
JUST TO THE WEST OF THE DULUTH CWA AS OF 10 AM..WITH MODERATE TO
STRONG FORCING FOR ASCENT PERSISTING ACROSS MUCH OF THE DULUTH
CWA. IT TOOK A BIT LONGER FOR THE FORCING TO ATTAIN DEEP LAYER
SATURATION THAN THE MODEL GUIDANCE FROM YDAY INDICATED..BUT ONCE
SATURATION WAS ACHIEVED..WE EXPERIENCED A RATHER EXPLOSIVE INCREASE
IN AREAL COVERAGE OF RADAR ECHOES BETWEEN 8-9 AM OVER PRETTY MUCH
THE ENTIRE EASTERN HALF OF THE DULUTH CWA.
PTYPE HAS STILL BEEN A HEADACHE. WITH RAPID NEWD ADVECTION OF
STRONG WARM NOSE ALOFT..PRECIP HAS BEEN ALMOST ALL FREEZING RAIN
SOUTH/WEST OF A LINE ROUGHLY FROM VOYAGEURS N.P. TO SILVER BAY.
HOWEVER..PRECIP IS STARTING AS SNOW OR A WINTRY MIX OVER THE
ARROWHEAD..BUT SHUD TRANSITION TO MORE SLEET/FZRA THERE BY EARLY
AFTERNOON..ALTHOUGH IT MAY BE A BIT HARDER TO WARM THE LOWER PART
OF THE TEMP PROFILE NOW THAT IT IS SATURATED OVER THE ARROWHEAD.
THE MAIN CHANGES FOR THE MORNING UPDATE THAT WAS MADE AVAILABLE
ABOUT 45 MINUTES AGO WERE TO 1) DRASTICALLY INCREASE POPS TO
ACCOUNT FOR WIDESPREAD PRECIP COVERAGE THRU EARLY AFTERNOON 2)
TWEAK PTYPE IN LINE WITH OBS AND SHORT RANGE GUIDANCE 3) INCREASE
SKY COVER TO NEAR 100 PERCENT AND 4) LOWER TEMPS..ESP OVER THE
NORTHEAST HALF OF THE CWA. NO CHANGES WERE MADE TO THE ADVISORY AT
THIS TIME. ADDITIONAL LIGHT PRECIP MAY REDEVELOP ALONG THE WESTERN
EDGE OF THE DULUTH CWA WHERE FORCING FOR ASCENT IS STILL
OCCURRING..BUT TEMPS SHOULD BE PUSHING THE FREEZING POINT OUT WEST
BY MIDDAY AS THE SURFACE WARM FRONT MAKES SLOW EASTWARD PROGRESS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM CST SUN JAN 12 2014
THIS WAS A CHALLENGING SHORT TERM FORECAST. THE MAIN FOCUS IS ON
THE POTENTIAL FOR FREEZING RAIN AND A WINTRY MIXTURE OF PCPN THIS
MORNING WITH A WARM FRONT IN THE NORTHERN PLAINS EARLY THIS
MORNING THAT WILL MOVE THROUGH THE NORTHLAND TODAY. THIS WARM
FRONT WILL BE ASSOCIATED WITH A LOW PRESSURE SYSTEM MOVING EAST
ACROSS SOUTH CENTRAL CANADA. THE MODEL SOUNDINGS CONTINUE TO
INDICATE A SHORT PERIOD WHERE SNOW ALOFT WILL FALL INTO A
RELATIVELY WARM LAYER ABOVE FREEZING (AROUND 1 TO 4 DEGREES
CELSIUS)...RESULTING IN FREEZING RAIN AND/OR SLEET AS IT FALLS TO
THE COLD SURFACE...WHICH IS BELOW FREEZING THIS MORNING.
THE CHALLENGING PART THOUGH IS THAT THERE ARE STILL SIGNIFICANT
DIFFERENCES BETWEEN THE MODELS AS TO THE TRACK AND PCPN AMOUNTS
TODAY. I WAS HOPING FOR BETTER MODEL AGREEMENT BY NOW COMPARED TO
MY PREVIOUS SHIFT. THE GFS/GEM/ECMWF/RAP13/HRRR PRIMARILY BRING
THE PCPN THROUGH NE MINNESOTA. ON THE OTHER HAND...THE NAM/WRF/GEM
REGIONAL WERE PRIMARILY BRINGING THE PCPN THROUGH THE INTERSTATE
35 CORRIDOR AND NW WISCONSIN. THE GFS IS MUCH MORE AGGRESSIVE WITH
THE PCPN THAN MOST OF THE OTHER MODELS...AND THE 06Z NAM12 CAME IN
WITH NO PCPN. THIS IS QUITE THE RANGE OF DIFFERENCES. IT APPEARS
THE RAP13 AND HRRR MIGHT BE DOING FAIRLY WELL WITH THE CURRENT
PCPN IN THE NORTHERN PLAINS AT THIS POINT...SO I LEANING ON NE
MINNESOTA BEING THE MOST AFFECTED. HOWEVER...I EXPANDED THE
FREEZING RAIN ACCUMULATION AND WINTER WEATHER ADVISORY TO MUCH OF
NW WISCONSIN SINCE THIS AREA COULD EASILY GET A LIGHT COATING OF
ICE TO MAKE FOR DIFFICULT TRAVEL CONDITIONS.
I EXPECT MUCH OF NE MINNESOTA AND NW WISCONSIN TO GET A LIGHT
COATING OF ICE...AROUND A COUPLE HUNDREDTHS OF AN INCH...THIS
MORNING. SOME ISOLATED LOCATIONS COULD GET UP TO AROUND 5
HUNDREDTHS OF AN INCH DEPENDING ON ANY MORE INTENSE SHOWER BANDS
THAT SET UP. THIS WILL LIKELY CAUSE DIFFICULT TRAVEL CONDITIONS
THIS MORNING UNTIL CONDITIONS BEGIN TO IMPROVE THIS AFTERNOON WITH
THE WARMING TEMPERATURES AND AS THE PCPN BEGINS TO EXIT THE
NORTHLAND.
THE MODEL AND MOS GUIDANCE IS IN PRETTY GOOD AGREEMENT WITH HIGH
TEMPERATURES TODAY WITH WIDESPREAD HIGHS IN THE MID 30S. THE
ARROWHEAD WILL MORE LIKELY REACH THE LOW 30S...WHILE THE BRAINERD
LAKES AREA MORE IN THE UPPER 30S. THERE WILL LIKELY BE SOME
PARTIAL CLEARING THIS AFTERNOON IN THE WAKE OF THE WARM FRONT.
TONIGHT...THE CANADIAN LOW PRESSURE WILL MOVE INTO CENTRAL
ONTARIO...AND ITS COLD FRONT WILL MOVE THROUGH THE NORTHLAND. THIS
WILL BRING COLDER TEMPERATURES WITH LOWS DIPPING DOWN TO THE TEENS
AND SINGLE DIGITS ACROSS NE MINNESOTA. THERE COULD BE LIGHT SNOW
WITH LITTLE TO NO ACCUMULATION ACROSS MUCH OF NE MINNESOTA.
MONDAY...HIGH TEMPERATURES WILL BE SIGNIFICANTLY COLDER THAN TODAY
WITH HIGHS IN THE TEENS AND LOW 20S. THERE MIGHT BE LINGERING
LIGHT SNOW IN THE MORNING...AND THEN A WEAK RIDGE OF HIGH PRESSURE
IN THE NORTHERN PLAINS WILL SHIFT INTO THE NORTHLAND DURING THE
AFTERNOON. THIS COULD BRING SOME PARTIAL CLEARING DURING THE
AFTERNOON...BUT I LEANED ON THE CLOUDIER SIDE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 343 AM CST SUN JAN 12 2014
A SERIES OF DISTURBANCES WILL IMPACT THE NORTHLAND THROUGH THE
EXTENDED PERIOD.
A CLIPPER WILL MOVE SOUTHEAST THROUGH THE AREA MONDAY NIGHT INTO
TUESDAY MORNING BRINGING THE POTENTIAL FOR A COUPLE INCHES OF SNOW
TO ABOUT THE SOUTHERN HALF/THIRD OF THE NORTHLAND. THE MODELS ARE
IN BETTER AGREEMENT TONIGHT THAN 24 HOURS AGO...BUT DIFFERENCES
REMAIN. THE ECMWF/GFS ARE FURTHER NORTH WITH THE TRACK OF THE LOW
AND WITH THE PRECIP...BUT THE LATEST NAM HAS TRENDED A BIT FURTHER
SOUTH. WE RAISED POPS TO LIKELY OVER OUR FAR SOUTHERN
ZONES...WHERE THE BEST CHANCE FOR 1 TO 2 INCHES OF SNOW EXISTS.
SOME HIGHER SNOWFALL AMOUNTS WILL ALSO BE POSSIBLE IN THE SNOWBELT
OF ASHLAND/IRON COUNTIES MONDAY NIGHT INTO TUESDAY DUE TO COLDER
AIR MOVING OVER THE LAKE ON NORTHWEST LOW LEVEL FLOW.
MOST AREAS WILL BE DRY TUESDAY AFTERNOON INTO TUESDAY NIGHT AS A
RIDGE MOVES OVER THE REGION. LAKE EFFECT SNOW WILL CONTINUE TO
BE POSSIBLE OVER PORTIONS OF THE SNOWBELT OF ASHLAND/IRON
COUNTIES.
A STRONGER SYSTEM WILL START TO IMPACT THE NORTHLAND WEDNESDAY. A
SURFACE LOW WILL TRACK FROM MANITOBA WEDNESDAY EVENING SOUTHEAST
TOWARD EASTERN LAKE SUPERIOR/NORTHERN MICHIGAN BY THURSDAY
EVENING. A STRONG AREA OF WAA WILL OCCUR AHEAD OF THE LOW
WEDNESDAY...BRINGING A CHANCE FOR PRECIPITATION TO MUCH OF THE
NORTHLAND BY WEDNESDAY AFTERNOON OR WEDNESDAY NIGHT. WE RAISED
POPS WEDNESDAY INTO WEDNESDAY NIGHT FOR MOST AREAS...AS A PERIOD
OF PRECIPITATION IS LOOKING MORE LIKELY. AT THIS TIME...WE HAVE
HIGHEST POPS OVER NORTHERN MINNESOTA. THE SYSTEM DOES NOT LOOK
QUITE AS WARM AS EARLIER MODEL RUNS...BUT WE DID KEEP A MENTION OF
FREEZING RAIN OVER PORTIONS OF OUR SOUTHERN AREA WEDNESDAY
AFTERNOON. LIGHT TO MODERATE SNOW ACCUMULATIONS WILL BE POSSIBLE
FROM WEDNESDAY AFTERNOON INTO THURSDAY. A PERIOD OF WINDY
CONDITIONS WILL ACCOMPANY A COLD FRONTAL PASSAGE WEDNESDAY NIGHT
INTO THURSDAY. WE HAVE HIGH TEMPS THURSDAY FROM 20 ALONG THE
INTERNATIONAL BORDER TO THE MID TWENTIES ACROSS THE SOUTH. THESE
WILL LIKELY FALL THROUGH THE DAY AS STRONG COLD AIR ADVECTION
OCCURS.
NORTHERLY WINDS THURSDAY INTO FRIDAY WILL COMBINE WITH THE MUCH
COLDER AIR TO PRODUCE A PERIOD OF LAKE EFFECT SNOW SHOWERS ALONG
THE SOUTH SHORE...ESPECIALLY ASHLAND/IRON COUNTIES. THE POTENTIAL
FOR SIGNIFICANT SNOWFALL EXISTS THURSDAY INTO FRIDAY.
MOST AREAS LOOK TO BE DRY FRIDAY INTO THE WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1204 PM CST SUN JAN 12 2014
MAIN AREA OF FREEZING RAIN IS NOW MOSTLY EAST OF THE
TERMINALS...THOUGH EXPECT THAT KDLH AND KHIB MAY STILL GET SOME
SHOWERS FOR A COUPLE MORE HOURS...BUT ONLY WITH MVFR CONDITIONS IN
THE SHOWERS. KHIB STILL IN MVFR...BUT EXPECT THEM TO GO VFR BY
20Z. REMAINDER OF TAF SITES TO REMAIN VFR THROUGH THE AFTERNOON
AND EVENING. AFTER 05Z AN AREA OF STRATUS TO PUSH INTO THE AREA
FROM THE NORTHWEST...BRINGING MVFR STRATUS 15HFT-25HFT. SCATTERED
SNOW SHOWERS EXPECTED WITH THIS STRATUS...BUT TIMING AND LOCATION
UNCERTAIN SO HAVE VCSH FOR NOW.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 33 16 19 6 / 70 10 10 30
INL 34 7 11 -4 / 60 30 20 10
BRD 37 15 18 10 / 70 10 10 70
HYR 35 21 23 8 / 50 10 20 70
ASX 34 21 23 8 / 60 10 10 50
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR MNZ010-011-018-
019-025-026-033>038.
WINTER WEATHER ADVISORY UNTIL 2 PM CST THIS AFTERNOON FOR MNZ012-
020-021.
WI...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR WIZ001>003-
006>008.
LS...NONE.
&&
$$
UPDATE...LE
SHORT TERM...GROCHOCINSKI
LONG TERM...MELDE
AVIATION...LE
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1011 AM CST SUN JAN 12 2014
.UPDATE...
ISSUED AT 1011 AM CST SUN JAN 12 2014
MAIN UPPER LEVEL WAVE AXIS AND EFFECTIVE SURFACE WARM FRONT LIE
JUST TO THE WEST OF THE DULUTH CWA AS OF 10 AM..WITH MODERATE TO
STRONG FORCING FOR ASCENT PERSISTING ACROSS MUCH OF THE DULUTH
CWA. IT TOOK A BIT LONGER FOR THE FORCING TO ATTAIN DEEP LAYER
SATURATION THAN THE MODEL GUIDANCE FROM YDAY INDICATED..BUT ONCE
SATURATION WAS ACHIEVED..WE EXPERIENCED A RATHER EXPLOSIVE INCREASE
IN AREAL COVERAGE OF RADAR ECHOES BETWEEN 8-9 AM OVER PRETTY MUCH
THE ENTIRE EASTERN HALF OF THE DULUTH CWA.
PTYPE HAS STILL BEEN A HEADACHE. WITH RAPID NEWD ADVECTION OF
STRONG WARM NOSE ALOFT..PRECIP HAS BEEN ALMOST ALL FREEZING RAIN
SOUTH/WEST OF A LINE ROUGHLY FROM VOYAGEURS N.P. TO SILVER BAY.
HOWEVER..PRECIP IS STARTING AS SNOW OR A WINTRY MIX OVER THE
ARROWHEAD..BUT SHUD TRANSITION TO MORE SLEET/FZRA THERE BY EARLY
AFTERNOON..ALTHOUGH IT MAY BE A BIT HARDER TO WARM THE LOWER PART
OF THE TEMP PROFILE NOW THAT IT IS SATURATED OVER THE ARROWHEAD.
THE MAIN CHANGES FOR THE MORNING UPDATE THAT WAS MADE AVAILABLE
ABOUT 45 MINUTES AGO WERE TO 1) DRASTICALLY INCREASE POPS TO
ACCOUNT FOR WIDESPREAD PRECIP COVERAGE THRU EARLY AFTERNOON 2)
TWEAK PTYPE IN LINE WITH OBS AND SHORT RANGE GUIDANCE 3) INCREASE
SKY COVER TO NEAR 100 PERCENT AND 4) LOWER TEMPS..ESP OVER THE
NORTHEAST HALF OF THE CWA. NO CHANGES WERE MADE TO THE ADVISORY AT
THIS TIME. ADDITIONAL LIGHT PRECIP MAY REDEVELOP ALONG THE WESTERN
EDGE OF THE DULUTH CWA WHERE FORCING FOR ASCENT IS STILL
OCCURRING..BUT TEMPS SHOULD BE PUSHING THE FREEZING POINT OUT WEST
BY MIDDAY AS THE SURFACE WARM FRONT MAKES SLOW EASTWARD PROGRESS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM CST SUN JAN 12 2014
THIS WAS A CHALLENGING SHORT TERM FORECAST. THE MAIN FOCUS IS ON
THE POTENTIAL FOR FREEZING RAIN AND A WINTRY MIXTURE OF PCPN THIS
MORNING WITH A WARM FRONT IN THE NORTHERN PLAINS EARLY THIS
MORNING THAT WILL MOVE THROUGH THE NORTHLAND TODAY. THIS WARM
FRONT WILL BE ASSOCIATED WITH A LOW PRESSURE SYSTEM MOVING EAST
ACROSS SOUTH CENTRAL CANADA. THE MODEL SOUNDINGS CONTINUE TO
INDICATE A SHORT PERIOD WHERE SNOW ALOFT WILL FALL INTO A
RELATIVELY WARM LAYER ABOVE FREEZING (AROUND 1 TO 4 DEGREES
CELSIUS)...RESULTING IN FREEZING RAIN AND/OR SLEET AS IT FALLS TO
THE COLD SURFACE...WHICH IS BELOW FREEZING THIS MORNING.
THE CHALLENGING PART THOUGH IS THAT THERE ARE STILL SIGNIFICANT
DIFFERENCES BETWEEN THE MODELS AS TO THE TRACK AND PCPN AMOUNTS
TODAY. I WAS HOPING FOR BETTER MODEL AGREEMENT BY NOW COMPARED TO
MY PREVIOUS SHIFT. THE GFS/GEM/ECMWF/RAP13/HRRR PRIMARILY BRING
THE PCPN THROUGH NE MINNESOTA. ON THE OTHER HAND...THE NAM/WRF/GEM
REGIONAL WERE PRIMARILY BRINGING THE PCPN THROUGH THE INTERSTATE
35 CORRIDOR AND NW WISCONSIN. THE GFS IS MUCH MORE AGGRESSIVE WITH
THE PCPN THAN MOST OF THE OTHER MODELS...AND THE 06Z NAM12 CAME IN
WITH NO PCPN. THIS IS QUITE THE RANGE OF DIFFERENCES. IT APPEARS
THE RAP13 AND HRRR MIGHT BE DOING FAIRLY WELL WITH THE CURRENT
PCPN IN THE NORTHERN PLAINS AT THIS POINT...SO I LEANING ON NE
MINNESOTA BEING THE MOST AFFECTED. HOWEVER...I EXPANDED THE
FREEZING RAIN ACCUMULATION AND WINTER WEATHER ADVISORY TO MUCH OF
NW WISCONSIN SINCE THIS AREA COULD EASILY GET A LIGHT COATING OF
ICE TO MAKE FOR DIFFICULT TRAVEL CONDITIONS.
I EXPECT MUCH OF NE MINNESOTA AND NW WISCONSIN TO GET A LIGHT
COATING OF ICE...AROUND A COUPLE HUNDREDTHS OF AN INCH...THIS
MORNING. SOME ISOLATED LOCATIONS COULD GET UP TO AROUND 5
HUNDREDTHS OF AN INCH DEPENDING ON ANY MORE INTENSE SHOWER BANDS
THAT SET UP. THIS WILL LIKELY CAUSE DIFFICULT TRAVEL CONDITIONS
THIS MORNING UNTIL CONDITIONS BEGIN TO IMPROVE THIS AFTERNOON WITH
THE WARMING TEMPERATURES AND AS THE PCPN BEGINS TO EXIT THE
NORTHLAND.
THE MODEL AND MOS GUIDANCE IS IN PRETTY GOOD AGREEMENT WITH HIGH
TEMPERATURES TODAY WITH WIDESPREAD HIGHS IN THE MID 30S. THE
ARROWHEAD WILL MORE LIKELY REACH THE LOW 30S...WHILE THE BRAINERD
LAKES AREA MORE IN THE UPPER 30S. THERE WILL LIKELY BE SOME
PARTIAL CLEARING THIS AFTERNOON IN THE WAKE OF THE WARM FRONT.
TONIGHT...THE CANADIAN LOW PRESSURE WILL MOVE INTO CENTRAL
ONTARIO...AND ITS COLD FRONT WILL MOVE THROUGH THE NORTHLAND. THIS
WILL BRING COLDER TEMPERATURES WITH LOWS DIPPING DOWN TO THE TEENS
AND SINGLE DIGITS ACROSS NE MINNESOTA. THERE COULD BE LIGHT SNOW
WITH LITTLE TO NO ACCUMULATION ACROSS MUCH OF NE MINNESOTA.
MONDAY...HIGH TEMPERATURES WILL BE SIGNIFICANTLY COLDER THAN TODAY
WITH HIGHS IN THE TEENS AND LOW 20S. THERE MIGHT BE LINGERING
LIGHT SNOW IN THE MORNING...AND THEN A WEAK RIDGE OF HIGH PRESSURE
IN THE NORTHERN PLAINS WILL SHIFT INTO THE NORTHLAND DURING THE
AFTERNOON. THIS COULD BRING SOME PARTIAL CLEARING DURING THE
AFTERNOON...BUT I LEANED ON THE CLOUDIER SIDE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 343 AM CST SUN JAN 12 2014
A SERIES OF DISTURBANCES WILL IMPACT THE NORTHLAND THROUGH THE
EXTENDED PERIOD.
A CLIPPER WILL MOVE SOUTHEAST THROUGH THE AREA MONDAY NIGHT INTO
TUESDAY MORNING BRINGING THE POTENTIAL FOR A COUPLE INCHES OF SNOW
TO ABOUT THE SOUTHERN HALF/THIRD OF THE NORTHLAND. THE MODELS ARE
IN BETTER AGREEMENT TONIGHT THAN 24 HOURS AGO...BUT DIFFERENCES
REMAIN. THE ECMWF/GFS ARE FURTHER NORTH WITH THE TRACK OF THE LOW
AND WITH THE PRECIP...BUT THE LATEST NAM HAS TRENDED A BIT FURTHER
SOUTH. WE RAISED POPS TO LIKELY OVER OUR FAR SOUTHERN
ZONES...WHERE THE BEST CHANCE FOR 1 TO 2 INCHES OF SNOW EXISTS.
SOME HIGHER SNOWFALL AMOUNTS WILL ALSO BE POSSIBLE IN THE SNOWBELT
OF ASHLAND/IRON COUNTIES MONDAY NIGHT INTO TUESDAY DUE TO COLDER
AIR MOVING OVER THE LAKE ON NORTHWEST LOW LEVEL FLOW.
MOST AREAS WILL BE DRY TUESDAY AFTERNOON INTO TUESDAY NIGHT AS A
RIDGE MOVES OVER THE REGION. LAKE EFFECT SNOW WILL CONTINUE TO
BE POSSIBLE OVER PORTIONS OF THE SNOWBELT OF ASHLAND/IRON
COUNTIES.
A STRONGER SYSTEM WILL START TO IMPACT THE NORTHLAND WEDNESDAY. A
SURFACE LOW WILL TRACK FROM MANITOBA WEDNESDAY EVENING SOUTHEAST
TOWARD EASTERN LAKE SUPERIOR/NORTHERN MICHIGAN BY THURSDAY
EVENING. A STRONG AREA OF WAA WILL OCCUR AHEAD OF THE LOW
WEDNESDAY...BRINGING A CHANCE FOR PRECIPITATION TO MUCH OF THE
NORTHLAND BY WEDNESDAY AFTERNOON OR WEDNESDAY NIGHT. WE RAISED
POPS WEDNESDAY INTO WEDNESDAY NIGHT FOR MOST AREAS...AS A PERIOD
OF PRECIPITATION IS LOOKING MORE LIKELY. AT THIS TIME...WE HAVE
HIGHEST POPS OVER NORTHERN MINNESOTA. THE SYSTEM DOES NOT LOOK
QUITE AS WARM AS EARLIER MODEL RUNS...BUT WE DID KEEP A MENTION OF
FREEZING RAIN OVER PORTIONS OF OUR SOUTHERN AREA WEDNESDAY
AFTERNOON. LIGHT TO MODERATE SNOW ACCUMULATIONS WILL BE POSSIBLE
FROM WEDNESDAY AFTERNOON INTO THURSDAY. A PERIOD OF WINDY
CONDITIONS WILL ACCOMPANY A COLD FRONTAL PASSAGE WEDNESDAY NIGHT
INTO THURSDAY. WE HAVE HIGH TEMPS THURSDAY FROM 20 ALONG THE
INTERNATIONAL BORDER TO THE MID TWENTIES ACROSS THE SOUTH. THESE
WILL LIKELY FALL THROUGH THE DAY AS STRONG COLD AIR ADVECTION
OCCURS.
NORTHERLY WINDS THURSDAY INTO FRIDAY WILL COMBINE WITH THE MUCH
COLDER AIR TO PRODUCE A PERIOD OF LAKE EFFECT SNOW SHOWERS ALONG
THE SOUTH SHORE...ESPECIALLY ASHLAND/IRON COUNTIES. THE POTENTIAL
FOR SIGNIFICANT SNOWFALL EXISTS THURSDAY INTO FRIDAY.
MOST AREAS LOOK TO BE DRY FRIDAY INTO THE WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 616 AM CST SUN JAN 12 2014
MAINLY VFR CONDITIONS COVERED THE NORTHLAND EARLY THIS
MORNING...WITH IFR CEILINGS OVER THE ARROWHEAD DOWN INTO THE TWIN
PORTS...AND AROUND KPBH TO KD25. PRECIP COVERAGE IS LIMITED SO FAR
THIS MORNING...CLOSER TO WHAT THE NAM WAS DEPICTING. WE HAVE A
TEMPO GROUP FOR MOST TAF SITES FOR SOME FZRA/PL THIS MORNING. THE
LATEST RAP SUGGESTS MVFR OR IFR CEILINGS WILL REDEVELOP THROUGH THE
DAY TODAY...BUT CONFIDENCE IS LOW ON WHETHER OR NOT THAT WILL
MATERIALIZE. A COLD FRONT WILL MOVE THROUGH THE NORTHLAND TONIGHT
CAUSING WINDS TO TURN W TO NW. A BETTER CHANCE FOR MVFR CEILINGS
WILL OCCUR LATER TONIGHT WITH STRONGER CAA BEHIND THE FRONT. SOME
LIGHT SNOW OR FLURRIES MAY ALSO OCCUR TONIGHT...MAINLY AFFECTING
KHIB/KINL.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 32 16 19 6 / 70 10 10 30
INL 35 7 11 -4 / 60 30 20 10
BRD 37 15 18 10 / 70 10 10 70
HYR 35 21 23 8 / 50 10 20 70
ASX 33 21 23 8 / 60 10 10 50
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR MNZ010-011-018-
019-025-026-033>038.
WINTER WEATHER ADVISORY UNTIL 2 PM CST THIS AFTERNOON FOR MNZ012-
020-021.
WI...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR WIZ001>003-
006>008.
LS...NONE.
&&
$$
UPDATE...MILLER
SHORT TERM...GROCHOCINSKI
LONG TERM...MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
854 AM CST SUN JAN 12 2014
.UPDATE...
ISSUED AT 854 AM CST SUN JAN 12 2014
HAVE HAD TO ISSUE A RATHER SHORT FUSE FREEZING RAIN ADVISORY IN
CENTRAL MINNESOTA FOR AREA OF LIGHT RAIN MOVING THROUGH. ALTHOUGH
MOST REPORTING LOCATIONS HAVE ONLY REPORTED PRECIP FOR 1 TO 2
HOURS...WITH TEMPERATURES RANGING FROM 28 TO 32...WE HAVE SEEN A
SIGNIFICANT AMOUNT OF TRAVEL CONCERNS DEVELOP ACROSS CENTRAL MN
WITH ICING CONDITIONS. MNDOT TRAVEL MAP HAS CATEGORIZED ROADS
ACROSS CENTRAL MN AS HAZARDOUS WITH TRAVEL NOT ADVISED...WHICH WAS
A BIG REASON FOR ISSUING THIS ADVISORY.
HOPWRF AND HRRR SHOW THIS BAND OF PRECIP LIFTING NE TOWARD
DLH...SO SEE NO NEED TO EXPAND THE FREEZING RAIN ADVISORY EAST
INTO WEST CENTRAL WI...AS ALL SHORT TERM MODELS INDICATE THAT THEY
WILL SEE NO PRECIPITATION OVER THERE. THE WEST EDGE OF THE ADVISORY
WAS SET BASED ON WHERE PRECIP IS CURRENTLY FALLING...COULD HAVE
ADDED BENSON UP THROUGH ALEXANDRIA TO THE ADVISORY...BUT RAIN
THERE IS ALREADY DONE...WITH TEMPERATURES ALREADY STARTING TO
SNEAK ABOVE FREEZING WEST OF THE ADVY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 228 AM CST SUN JAN 12 2014
LATEST WATER VAPOR IMAGERY SHOWS HIGH CLOUDS AND MOISTURE MOVING
EAST WITH THE UPPER RIDGE AXIS ACROSS THE REGION AT THE CURRENT
TIME. THIS HAS HELPED TO INCREASE THE MID-HIGH CLOUDS OVER OUR
AREA... WITH LOWER CLOUDS STILL TO THE WEST WHERE SOME PCPN IS
APPARENT ON RADAR AND SURFACE OBS. THAT PCPN IS PRIMARILY BEING
FORCED BY SOME DECENT ISENTROPIC LIFT AHEAD OF THE UPPER TROUGH...
WHICH IS LAGGING BACK WELL TO THE WEST. THE CURRENT AREA OF PCPN
WILL TRY TO HOLD TOGETHER AS IT MOVES EAST TODAY... BUT IT STILL
APPEARS THAT THE BEST CHANCE FOR PCPN WILL BE OVER THE FAR NORTHERN
PART OF THE FORECAST AREA... WHERE DEEPER MOISTURE LOOKS TO BE
PRESENT THROUGH THE DAY. HOWEVER... EVEN THERE IT DOESN/T APPEAR AS
THOUGH PCPN AMOUNTS WILL BE SUBSTANTIAL... AND IT/S POSSIBLE SOME
LOCATIONS WON/T MEASURE AT ALL... SO STILL KEPT POPS AS CHANCES
RATHER THAN LIKELY. PCPN-TYPE WITH WHATEVER OCCURS WILL BE TRICKY...
SINCE TEMPERATURES ARE ALREADY CLIMBING ABOVE FREEZING ALOFT... AS
WAS EVIDENT IN THE UPSTREAM SOUNDINGS AT 00Z WHICH SHOWED THE WARM
NOSE AROUND 900-850MB. WITH CONTINUED WARM ADVECTION THROUGH THE DAY
THAT SITUATION SHOULDN/T IMPROVE. SO... WOULD EXPECT PARTIAL TO
COMPLETE MELTING OF PCPN ALOFT... BUT SURFACE TEMPERATURES WILL TAKE
A BIT OF TIME BEFORE THEY CLIMB ABOVE FREEZING TODAY... SO THERE
STILL APPEARS TO BE A CHANCE FOR SOME SLEET AND FREEZING
RAIN/DRIZZLE THIS MORNING WITH ANY PCPN WHICH MOVES ACROSS THE
NORTHERN PORTION OF THE AREA. BUT... AS MENTIONED... WHATEVER OCCURS
SHOULD BE LIGHT. THE UPPER TROUGH CURRENTLY EVIDENT ON WATER VAPOR
OVER THE WESTERN US WILL CONTINUE TO MOVE EAST TONIGHT... AND LOOKS
TO MOVE INTO THE WESTERN PART OF OUR AREA AFTER 06Z. WE/LL SEE AN
INITIAL COLD FRONT MOVE THROUGH THIS EVENING... WHICH WON/T DO TOO
MUCH TO COOL THINGS OFF... BUT WILL SERVE TO SHIFT WINDS AROUND TO
THE WEST AND NORTHWEST... FURTHER LIMITING THE CHANCE FOR ANY
MOISTURE RETURN AHEAD OF THE UPPER TROUGH AND MORE MEANINGFUL COLD
FRONT WHICH MOVES THROUGH OVERNIGHT. THERE COULD BE SOME LIGHT PCPN
LATE TONIGHT AS THE UPPER TROUGH AND SECONDARY FRONT MOVE THROUGH...
BUT AT THIS POINT IT DOESN/T LOOK TO BE ANY MORE THAN FLURRIES... SO
DIDN/T INCLUDE ANYTHING IN THE FORECAST. THE MAIN THING WILL BE THE
PUSH OF COLDER AIR THE SYSTEM BRINGS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 228 AM CST SUN JAN 12 2014
THE EXTENDED PERIOD WILL BE MARKED WITH A TWO STORM SYSTEMS WHICH
WILL AFFECT THE UPPER MIDWEST EARLY TUESDAY...AND THEN THURSDAY.
BOTH OF THESE SYSTEMS WILL HAVE A STRONG INFLUENCE OF THICKNESS
VALUES RISING ENOUGH TO CONSIDER A MIXTURE OF SLEET/FREEZING
RAIN/RAIN IN THE FAR SW CWA. EVEN IF WE DO GET PRECIPITATION IN
THIS AREA...THE INCREASING THICKNESS VALUES AND ASSOCIATED 85/92H
TEMPS RISING TO LIMIT THE BEST FORMATION OF ICE CRYSTALS /MORE
FREEZING RAIN/DRIZZLE AND SUPERCOOLED LIQUID WATER DROPLETS/...WILL
LIMIT SNOWFALL AMTS. BEST CHC OF RECEIVING MEASURABLE
PRECIPITATION IN SW/SC MN WILL OCCUR WITH EARLY TUESDAY/S SYSTEM.
TAKING A CROSS SECTION ALONG A KOMA TO KDLH LINE INDICATES THAT
BOTH THE GFS/EC HAVE SIMILAR SCENARIO/S OF A BRIEF PERIOD OF
STRONG LIFT ARND 6Z TUESDAY IN THE DENDRITIC SNOW ZONE. FORCING IS
VERY LIMITED 6 HRS BEFORE AND AFTER THIS TIME FRAME. AS DISCUSS
WITH THICKNESS VALUES AND THE INFLUENCE OF HIGHER 92H/85H
TEMPS...SNOWFALL AMTS MAY BE LIGHTER THAN EXPECTED. EVEN WITH A 13
TO 15-1 SNOWFALL RATIO BETWEEN 00-12Z TUESDAY...SNOWFALL AMTS WILL
RANGE FROM 1" TO 2.5". ALTHOUGH MODELS HAVE BEEN MORE CONSISTENT
IN TERMS OF A SFC LOW DEVELOPING ACROSS THE DAKOTAS...AND MOVING
THIS SYSTEM RAPIDLY SE ACROSS THE MIDWEST TUESDAY AFTN...PLACEMENT
OF THE SFC LOW WILL BE CRITICAL IN TERMS OF WHERE THE HEAVIER SNOW
BANDS DEVELOP EARLY TUESDAY. BASED ON CURRENT MODELS...THE BEST
PLACEMENT AND ASSOCIATED QPF FIELD HAS A BAND OF 1.5 TO 2.5" OF
SNOWFALL FROM LONG PRAIRIE...SE TO THE NORTHERN SUBURBS OF THE
TWIN CITIES...TO RIVER FALLS WI. ANY DEVIATION OF THIS SFC
LOW...OR STRONGER INFLUX OF WARMER AIR FROM THE SW...WILL LIMIT
SNOWFALL AMTS.
THURSDAY SYSTEM LOOKS TO BE MAINLY IN THE FORM OF SNOW...BUT DUE
TO THE FAST NATURE OF THE SYSTEM AND LIMITED DEEP MOISTURE AND
LIFT...AMTS WILL BE LIGHT AND FOCUSED NE OF MPX CWA. THE MAJOR
DIFFERENCES BETWEEN TUESDAY/S AND THURSDAY/S SYSTEM IS THE
PRESSURE GRADIENT AND ASSOCIATED STRONG SFC WIND FIELD. BASED ON
THE SFC WINDS AND GUST POTENTIAL...AND IF ANY SNOW CAN BE PICK UP
FROM THE GROUND...BLIZZARD LIKE CONDS MAY DEVELOP...ESPECIALLY IN
THE TYPICAL AREAS OF WC/SW/SC MN THU/THU NIGHT. HAVE INTRODUCED
BLOWING SNOW DURING THIS TIME FRAME...BUT IF CURRENT MODEL TRENDS
HAVE THE CONTINUED SFC PRESSURE GRADIENT FIELD THE SAME...A
BLIZZARD WATCH OR SOME OTHER HIGHLIGHTED WX EVENT IS POSSIBLE.
BEHIND THIS SYSTEM...ANOTHER ARCTIC OUTBREAK WILL OCCUR...BUT NOT
AS COLD AS THE FIRST WEEK OF JANUARY. 92H/85H TEMPS ARE 10 TO 15
DEGREES WARMER THAN THE ARCTIC CORE FROM EARLIER THIS MONTH.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 511 AM CST SUN JAN 12 2014
ALTHOUGH THERE WILL BE PLENTY OF CLOUD COVER THROUGH THE FORECAST
PERIOD... NEARLY ALL OF IT LOOKS TO BE VFR... WITH MOST OF THAT
AOA 10K FT AGL. WARM ADVECTION WILL BE FAIRLY STRONG OVER THE AREA
TODAY... WHICH IS HELPING PRODUCE WIDESPREAD MID-HIGH CLOUDS.
THERE HAS BEEN SOME VERY LIGHT PCPN OVER THE DAKOTAS OVERNIGHT...
BUT IT HAS BEEN DISSIPATING WHILE MOVING EAST INTO DRIER AIR... AS
WAS SUGGESTED BY THE HOPWRF... HRRR... AND EVEN THE COARSER
RESOLUTION GUIDANCE TO SOME EXTENT. THERE IS A SLIGHT CHANCE A BIT
OF THIS LIGHT PCPN COULD IMPACT THE NORTHERN SITES THIS MORNING...
BUT THE PROBABILITY IS TOO LOW TO INCLUDE IN THE TAFS. WE WILL SEE
AN UPPER TROUGH MOVE TOWARD THE AREA TONIGHT... WHICH WILL PUSH A
COLD FRONTAL BOUNDARY ACROSS THE REGION. THERE IS A CHANCE FOR
SOME MVFR CEILINGS BEHIND THE COLD FRONT... SO INCLUDED SOME
POTENTIAL FOR THAT TOWARD THE TAIL END OF THE TAFS. SOME LIGHT
SNOW/FLURRIES COULD ACCOMPANY THE POST FRONTAL COLD ADVECTION AND
STEEPENING LAPSE RATES... BUT AT THIS POINT IT DOESN/T LOOK TO
WARRANT ANY SORT OF VISIBILITY RESTRICTION.
KMSP...TAF REFLECTS EXPECTATIONS WITH GENERALLY HIGH CONFIDENCE.
ONLY CONCERN WOULD BE POTENTIAL FOR SOME MVFR CEILINGS VERY LATE
TONIGHT OR MONDAY MORNING... BUT PLAYED THINGS SOMEWHAT OPTIMISTIC
FOR NOW.
/OUTLOOK FOR KMSP/
MONDAY AFTERNOON...MVFR CEILINGS POSSIBLE. NORTHWEST WIND 10 TO 15 KT.
MONDAY NIGHT...MVFR CEILINGS AND VISIBILITIES EXPECTED WITH
SNOW... IFR CONDITIONS POSSIBLE. SOUTHWEST WIND 10 TO 20 KT
SHIFTING NORTHWEST.
TUESDAY...MVFR CEILINGS EXPECTED... MVFR VISIBILITIES POSSIBLE
WITH A CHANCE OF SNOW. NORTHWEST WIND 10 TO 20 KT.
TUESDAY NIGHT...MVFR CEILINGS POSSIBLE. NORTHWEST WIND 10 TO 15 KT.
WEDNESDAY...VFR. NORTHWEST WIND 5 TO 10 KT BECOMING SOUTHWEST 10
TO 20 KT.
WEDNESDAY NIGHT...MVFR CEILINGS POSSIBLE LATE. SOUTHWEST WIND 15
TO 25 KT.
THURSDAY...MVFR CEILINGS EXPECTED... MVFR VISIBILITIES POSSIBLE
WITH A CHANCE OF SNOW. WEST WIND 15 TO 25 KT SHIFTING NORTHWEST
WITH GUSTS TO 35 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...FREEZING RAIN ADVISORY UNTIL NOON CST TODAY FOR MNZ042>045-049-
050.
WI...NONE.
&&
$$
UPDATE...MPG
SHORT TERM...
LONG TERM...JLT
AVIATION...
AREA FORECAST DISCUSSION
NWS DULUTH MN
617 AM CST SUN JAN 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM CST SUN JAN 12 2014
THIS WAS A CHALLENGING SHORT TERM FORECAST. THE MAIN FOCUS IS ON
THE POTENTIAL FOR FREEZING RAIN AND A WINTRY MIXTURE OF PCPN THIS
MORNING WITH A WARM FRONT IN THE NORTHERN PLAINS EARLY THIS
MORNING THAT WILL MOVE THROUGH THE NORTHLAND TODAY. THIS WARM
FRONT WILL BE ASSOCIATED WITH A LOW PRESSURE SYSTEM MOVING EAST
ACROSS SOUTH CENTRAL CANADA. THE MODEL SOUNDINGS CONTINUE TO
INDICATE A SHORT PERIOD WHERE SNOW ALOFT WILL FALL INTO A
RELATIVELY WARM LAYER ABOVE FREEZING (AROUND 1 TO 4 DEGREES
CELSIUS)...RESULTING IN FREEZING RAIN AND/OR SLEET AS IT FALLS TO
THE COLD SURFACE...WHICH IS BELOW FREEZING THIS MORNING.
THE CHALLENGING PART THOUGH IS THAT THERE ARE STILL SIGNIFICANT
DIFFERENCES BETWEEN THE MODELS AS TO THE TRACK AND PCPN AMOUNTS
TODAY. I WAS HOPING FOR BETTER MODEL AGREEMENT BY NOW COMPARED TO
MY PREVIOUS SHIFT. THE GFS/GEM/ECMWF/RAP13/HRRR PRIMARILY BRING
THE PCPN THROUGH NE MINNESOTA. ON THE OTHER HAND...THE NAM/WRF/GEM
REGIONAL WERE PRIMARILY BRINGING THE PCPN THROUGH THE INTERSTATE
35 CORRIDOR AND NW WISCONSIN. THE GFS IS MUCH MORE AGGRESSIVE WITH
THE PCPN THAN MOST OF THE OTHER MODELS...AND THE 06Z NAM12 CAME IN
WITH NO PCPN. THIS IS QUITE THE RANGE OF DIFFERENCES. IT APPEARS
THE RAP13 AND HRRR MIGHT BE DOING FAIRLY WELL WITH THE CURRENT
PCPN IN THE NORTHERN PLAINS AT THIS POINT...SO I LEANING ON NE
MINNESOTA BEING THE MOST AFFECTED. HOWEVER...I EXPANDED THE
FREEZING RAIN ACCUMULATION AND WINTER WEATHER ADVISORY TO MUCH OF
NW WISCONSIN SINCE THIS AREA COULD EASILY GET A LIGHT COATING OF
ICE TO MAKE FOR DIFFICULT TRAVEL CONDITIONS.
I EXPECT MUCH OF NE MINNESOTA AND NW WISCONSIN TO GET A LIGHT
COATING OF ICE...AROUND A COUPLE HUNDREDTHS OF AN INCH...THIS
MORNING. SOME ISOLATED LOCATIONS COULD GET UP TO AROUND 5
HUNDREDTHS OF AN INCH DEPENDING ON ANY MORE INTENSE SHOWER BANDS
THAT SET UP. THIS WILL LIKELY CAUSE DIFFICULT TRAVEL CONDITIONS
THIS MORNING UNTIL CONDITIONS BEGIN TO IMPROVE THIS AFTERNOON WITH
THE WARMING TEMPERATURES AND AS THE PCPN BEGINS TO EXIT THE
NORTHLAND.
THE MODEL AND MOS GUIDANCE IS IN PRETTY GOOD AGREEMENT WITH HIGH
TEMPERATURES TODAY WITH WIDESPREAD HIGHS IN THE MID 30S. THE
ARROWHEAD WILL MORE LIKELY REACH THE LOW 30S...WHILE THE BRAINERD
LAKES AREA MORE IN THE UPPER 30S. THERE WILL LIKELY BE SOME
PARTIAL CLEARING THIS AFTERNOON IN THE WAKE OF THE WARM FRONT.
TONIGHT...THE CANADIAN LOW PRESSURE WILL MOVE INTO CENTRAL
ONTARIO...AND ITS COLD FRONT WILL MOVE THROUGH THE NORTHLAND. THIS
WILL BRING COLDER TEMPERATURES WITH LOWS DIPPING DOWN TO THE TEENS
AND SINGLE DIGITS ACROSS NE MINNESOTA. THERE COULD BE LIGHT SNOW
WITH LITTLE TO NO ACCUMULATION ACROSS MUCH OF NE MINNESOTA.
MONDAY...HIGH TEMPERATURES WILL BE SIGNIFICANTLY COLDER THAN TODAY
WITH HIGHS IN THE TEENS AND LOW 20S. THERE MIGHT BE LINGERING
LIGHT SNOW IN THE MORNING...AND THEN A WEAK RIDGE OF HIGH PRESSURE
IN THE NORTHERN PLAINS WILL SHIFT INTO THE NORTHLAND DURING THE
AFTERNOON. THIS COULD BRING SOME PARTIAL CLEARING DURING THE
AFTERNOON...BUT I LEANED ON THE CLOUDIER SIDE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 343 AM CST SUN JAN 12 2014
A SERIES OF DISTURBANCES WILL IMPACT THE NORTHLAND THROUGH THE
EXTENDED PERIOD.
A CLIPPER WILL MOVE SOUTHEAST THROUGH THE AREA MONDAY NIGHT INTO
TUESDAY MORNING BRINGING THE POTENTIAL FOR A COUPLE INCHES OF SNOW
TO ABOUT THE SOUTHERN HALF/THIRD OF THE NORTHLAND. THE MODELS ARE
IN BETTER AGREEMENT TONIGHT THAN 24 HOURS AGO...BUT DIFFERENCES
REMAIN. THE ECMWF/GFS ARE FURTHER NORTH WITH THE TRACK OF THE LOW
AND WITH THE PRECIP...BUT THE LATEST NAM HAS TRENDED A BIT FURTHER
SOUTH. WE RAISED POPS TO LIKELY OVER OUR FAR SOUTHERN
ZONES...WHERE THE BEST CHANCE FOR 1 TO 2 INCHES OF SNOW EXISTS.
SOME HIGHER SNOWFALL AMOUNTS WILL ALSO BE POSSIBLE IN THE SNOWBELT
OF ASHLAND/IRON COUNTIES MONDAY NIGHT INTO TUESDAY DUE TO COLDER
AIR MOVING OVER THE LAKE ON NORTHWEST LOW LEVEL FLOW.
MOST AREAS WILL BE DRY TUESDAY AFTERNOON INTO TUESDAY NIGHT AS A
RIDGE MOVES OVER THE REGION. LAKE EFFECT SNOW WILL CONTINUE TO
BE POSSIBLE OVER PORTIONS OF THE SNOWBELT OF ASHLAND/IRON
COUNTIES.
A STRONGER SYSTEM WILL START TO IMPACT THE NORTHLAND WEDNESDAY. A
SURFACE LOW WILL TRACK FROM MANITOBA WEDNESDAY EVENING SOUTHEAST
TOWARD EASTERN LAKE SUPERIOR/NORTHERN MICHIGAN BY THURSDAY
EVENING. A STRONG AREA OF WAA WILL OCCUR AHEAD OF THE LOW
WEDNESDAY...BRINGING A CHANCE FOR PRECIPITATION TO MUCH OF THE
NORTHLAND BY WEDNESDAY AFTERNOON OR WEDNESDAY NIGHT. WE RAISED
POPS WEDNESDAY INTO WEDNESDAY NIGHT FOR MOST AREAS...AS A PERIOD
OF PRECIPITATION IS LOOKING MORE LIKELY. AT THIS TIME...WE HAVE
HIGHEST POPS OVER NORTHERN MINNESOTA. THE SYSTEM DOES NOT LOOK
QUITE AS WARM AS EARLIER MODEL RUNS...BUT WE DID KEEP A MENTION OF
FREEZING RAIN OVER PORTIONS OF OUR SOUTHERN AREA WEDNESDAY
AFTERNOON. LIGHT TO MODERATE SNOW ACCUMULATIONS WILL BE POSSIBLE
FROM WEDNESDAY AFTERNOON INTO THURSDAY. A PERIOD OF WINDY
CONDITIONS WILL ACCOMPANY A COLD FRONTAL PASSAGE WEDNESDAY NIGHT
INTO THURSDAY. WE HAVE HIGH TEMPS THURSDAY FROM 20 ALONG THE
INTERNATIONAL BORDER TO THE MID TWENTIES ACROSS THE SOUTH. THESE
WILL LIKELY FALL THROUGH THE DAY AS STRONG COLD AIR ADVECTION
OCCURS.
NORTHERLY WINDS THURSDAY INTO FRIDAY WILL COMBINE WITH THE MUCH
COLDER AIR TO PRODUCE A PERIOD OF LAKE EFFECT SNOW SHOWERS ALONG
THE SOUTH SHORE...ESPECIALLY ASHLAND/IRON COUNTIES. THE POTENTIAL
FOR SIGNIFICANT SNOWFALL EXISTS THURSDAY INTO FRIDAY.
MOST AREAS LOOK TO BE DRY FRIDAY INTO THE WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 616 AM CST SUN JAN 12 2014
MAINLY VFR CONDITIONS COVERED THE NORTHLAND EARLY THIS
MORNING...WITH IFR CEILINGS OVER THE ARROWHEAD DOWN INTO THE TWIN
PORTS...AND AROUND KPBH TO KD25. PRECIP COVERAGE IS LIMITED SO FAR
THIS MORNING...CLOSER TO WHAT THE NAM WAS DEPICTING. WE HAVE A
TEMPO GROUP FOR MOST TAF SITES FOR SOME FZRA/PL THIS MORNING. THE
LATEST RAP SUGGESTS MVFR OR IFR CEILINGS WILL REDEVELOP THROUGH THE
DAY TODAY...BUT CONFIDENCE IS LOW ON WHETHER OR NOT THAT WILL
MATERIALIZE. A COLD FRONT WILL MOVE THROUGH THE NORTHLAND TONIGHT
CAUSING WINDS TO TURN W TO NW. A BETTER CHANCE FOR MVFR CEILINGS
WILL OCCUR LATER TONIGHT WITH STRONGER CAA BEHIND THE FRONT. SOME
LIGHT SNOW OR FLURRIES MAY ALSO OCCUR TONIGHT...MAINLY AFFECTING
KHIB/KINL.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 34 16 19 6 / 40 10 10 30
INL 36 7 11 -4 / 40 30 20 10
BRD 38 15 18 10 / 50 10 10 70
HYR 37 21 23 8 / 40 10 20 70
ASX 36 21 23 8 / 40 10 10 50
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR MNZ010-011-018-
019-025-026-033>038.
WINTER WEATHER ADVISORY UNTIL 2 PM CST THIS AFTERNOON FOR MNZ012-
020-021.
WI...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR WIZ001-006.
WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR WIZ002-003-007-
008.
LS...NONE.
&&
$$
SHORT TERM...GROCHOCINSKI
LONG TERM...MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS DULUTH MN
344 AM CST SUN JAN 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM CST SUN JAN 12 2014
THIS WAS A CHALLENGING SHORT TERM FORECAST. THE MAIN FOCUS IS ON
THE POTENTIAL FOR FREEZING RAIN AND A WINTRY MIXTURE OF PCPN THIS
MORNING WITH A WARM FRONT IN THE NORTHERN PLAINS EARLY THIS
MORNING THAT WILL MOVE THROUGH THE NORTHLAND TODAY. THIS WARM
FRONT WILL BE ASSOCIATED WITH A LOW PRESSURE SYSTEM MOVING EAST
ACROSS SOUTH CENTRAL CANADA. THE MODEL SOUNDINGS CONTINUE TO
INDICATE A SHORT PERIOD WHERE SNOW ALOFT WILL FALL INTO A
RELATIVELY WARM LAYER ABOVE FREEZING (AROUND 1 TO 4 DEGREES
CELSIUS)...RESULTING IN FREEZING RAIN AND/OR SLEET AS IT FALLS TO
THE COLD SURFACE...WHICH IS BELOW FREEZING THIS MORNING.
THE CHALLENGING PART THOUGH IS THAT THERE ARE STILL SIGNIFICANT
DIFFERENCES BETWEEN THE MODELS AS TO THE TRACK AND PCPN AMOUNTS
TODAY. I WAS HOPING FOR BETTER MODEL AGREEMENT BY NOW COMPARED TO
MY PREVIOUS SHIFT. THE GFS/GEM/ECMWF/RAP13/HRRR PRIMARILY BRING
THE PCPN THROUGH NE MINNESOTA. ON THE OTHER HAND...THE NAM/WRF/GEM
REGIONAL WERE PRIMARILY BRINGING THE PCPN THROUGH THE INTERSTATE
35 CORRIDOR AND NW WISCONSIN. THE GFS IS MUCH MORE AGGRESSIVE WITH
THE PCPN THAN MOST OF THE OTHER MODELS...AND THE 06Z NAM12 CAME IN
WITH NO PCPN. THIS IS QUITE THE RANGE OF DIFFERENCES. IT APPEARS
THE RAP13 AND HRRR MIGHT BE DOING FAIRLY WELL WITH THE CURRENT
PCPN IN THE NORTHERN PLAINS AT THIS POINT...SO I LEANING ON NE
MINNESOTA BEING THE MOST AFFECTED. HOWEVER...I EXPANDED THE
FREEZING RAIN ACCUMULATION AND WINTER WEATHER ADVISORY TO MUCH OF
NW WISCONSIN SINCE THIS AREA COULD EASILY GET A LIGHT COATING OF
ICE TO MAKE FOR DIFFICULT TRAVEL CONDITIONS.
I EXPECT MUCH OF NE MINNESOTA AND NW WISCONSIN TO GET A LIGHT
COATING OF ICE...AROUND A COUPLE HUNDREDTHS OF AN INCH...THIS
MORNING. SOME ISOLATED LOCATIONS COULD GET UP TO AROUND 5
HUNDREDTHS OF AN INCH DEPENDING ON ANY MORE INTENSE SHOWER BANDS
THAT SET UP. THIS WILL LIKELY CAUSE DIFFICULT TRAVEL CONDITIONS
THIS MORNING UNTIL CONDITIONS BEGIN TO IMPROVE THIS AFTERNOON WITH
THE WARMING TEMPERATURES AND AS THE PCPN BEGINS TO EXIT THE
NORTHLAND.
THE MODEL AND MOS GUIDANCE IS IN PRETTY GOOD AGREEMENT WITH HIGH
TEMPERATURES TODAY WITH WIDESPREAD HIGHS IN THE MID 30S. THE
ARROWHEAD WILL MORE LIKELY REACH THE LOW 30S...WHILE THE BRAINERD
LAKES AREA MORE IN THE UPPER 30S. THERE WILL LIKELY BE SOME
PARTIAL CLEARING THIS AFTERNOON IN THE WAKE OF THE WARM FRONT.
TONIGHT...THE CANADIAN LOW PRESSURE WILL MOVE INTO CENTRAL
ONTARIO...AND ITS COLD FRONT WILL MOVE THROUGH THE NORTHLAND. THIS
WILL BRING COLDER TEMPERATURES WITH LOWS DIPPING DOWN TO THE TEENS
AND SINGLE DIGITS ACROSS NE MINNESOTA. THERE COULD BE LIGHT SNOW
WITH LITTLE TO NO ACCUMULATION ACROSS MUCH OF NE MINNESOTA.
MONDAY...HIGH TEMPERATURES WILL BE SIGNIFICANTLY COLDER THAN TODAY
WITH HIGHS IN THE TEENS AND LOW 20S. THERE MIGHT BE LINGERING
LIGHT SNOW IN THE MORNING...AND THEN A WEAK RIDGE OF HIGH PRESSURE
IN THE NORTHERN PLAINS WILL SHIFT INTO THE NORTHLAND DURING THE
AFTERNOON. THIS COULD BRING SOME PARTIAL CLEARING DURING THE
AFTERNOON...BUT I LEANED ON THE CLOUDIER SIDE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 343 AM CST SUN JAN 12 2014
A SERIES OF DISTURBANCES WILL IMPACT THE NORTHLAND THROUGH THE
EXTENDED PERIOD.
A CLIPPER WILL MOVE SOUTHEAST THROUGH THE AREA MONDAY NIGHT INTO
TUESDAY MORNING BRINGING THE POTENTIAL FOR A COUPLE INCHES OF SNOW
TO ABOUT THE SOUTHERN HALF/THIRD OF THE NORTHLAND. THE MODELS ARE
IN BETTER AGREEMENT TONIGHT THAN 24 HOURS AGO...BUT DIFFERENCES
REMAIN. THE ECMWF/GFS ARE FURTHER NORTH WITH THE TRACK OF THE LOW
AND WITH THE PRECIP...BUT THE LATEST NAM HAS TRENDED A BIT FURTHER
SOUTH. WE RAISED POPS TO LIKELY OVER OUR FAR SOUTHERN
ZONES...WHERE THE BEST CHANCE FOR 1 TO 2 INCHES OF SNOW EXISTS.
SOME HIGHER SNOWFALL AMOUNTS WILL ALSO BE POSSIBLE IN THE SNOWBELT
OF ASHLAND/IRON COUNTIES MONDAY NIGHT INTO TUESDAY DUE TO COLDER
AIR MOVING OVER THE LAKE ON NORTHWEST LOW LEVEL FLOW.
MOST AREAS WILL BE DRY TUESDAY AFTERNOON INTO TUESDAY NIGHT AS A
RIDGE MOVES OVER THE REGION. LAKE EFFECT SNOW WILL CONTINUE TO
BE POSSIBLE OVER PORTIONS OF THE SNOWBELT OF ASHLAND/IRON
COUNTIES.
A STRONGER SYSTEM WILL START TO IMPACT THE NORTHLAND WEDNESDAY. A
SURFACE LOW WILL TRACK FROM MANITOBA WEDNESDAY EVENING SOUTHEAST
TOWARD EASTERN LAKE SUPERIOR/NORTHERN MICHIGAN BY THURSDAY
EVENING. A STRONG AREA OF WAA WILL OCCUR AHEAD OF THE LOW
WEDNESDAY...BRINGING A CHANCE FOR PRECIPITATION TO MUCH OF THE
NORTHLAND BY WEDNESDAY AFTERNOON OR WEDNESDAY NIGHT. WE RAISED
POPS WEDNESDAY INTO WEDNESDAY NIGHT FOR MOST AREAS...AS A PERIOD
OF PRECIPITATION IS LOOKING MORE LIKELY. AT THIS TIME...WE HAVE
HIGHEST POPS OVER NORTHERN MINNESOTA. THE SYSTEM DOES NOT LOOK
QUITE AS WARM AS EARLIER MODEL RUNS...BUT WE DID KEEP A MENTION OF
FREEZING RAIN OVER PORTIONS OF OUR SOUTHERN AREA WEDNESDAY
AFTERNOON. LIGHT TO MODERATE SNOW ACCUMULATIONS WILL BE POSSIBLE
FROM WEDNESDAY AFTERNOON INTO THURSDAY. A PERIOD OF WINDY
CONDITIONS WILL ACCOMPANY A COLD FRONTAL PASSAGE WEDNESDAY NIGHT
INTO THURSDAY. WE HAVE HIGH TEMPS THURSDAY FROM 20 ALONG THE
INTERNATIONAL BORDER TO THE MID TWENTIES ACROSS THE SOUTH. THESE
WILL LIKELY FALL THROUGH THE DAY AS STRONG COLD AIR ADVECTION
OCCURS.
NORTHERLY WINDS THURSDAY INTO FRIDAY WILL COMBINE WITH THE MUCH
COLDER AIR TO PRODUCE A PERIOD OF LAKE EFFECT SNOW SHOWERS ALONG
THE SOUTH SHORE...ESPECIALLY ASHLAND/IRON COUNTIES. THE POTENTIAL
FOR SIGNIFICANT SNOWFALL EXISTS THURSDAY INTO FRIDAY.
MOST AREAS LOOK TO BE DRY FRIDAY INTO THE WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1133 PM CST SAT JAN 11 2014
A MIX OF MVFR/IFR CEILINGS AROUND 800-1200 FT WILL PREVAIL THROUGH
THE EARLY MORNING AS MID LEVEL CEILINGS INCREASE FROM THE WEST.
A BRIEF WINDOW OF VFR IS EXPECTED THROUGH DAYBREAK AS A RIDGE OF
HIGH PRESSURE TRACKS OVER THE NORTHLAND. HAVE LOW LEVEL WIND SHEAR
LATE TONIGHT AT ALL MN TERMINALS AS 2 KFT WINDS INCREASE OUT OF
THE SOUTH AROUND 40 KT. A SURGE OF WARM MID- LEVEL AIR AHEAD OF A
FAST MOVING TROUGH WILL BRING A THREAT FOR -FZRA/-SN LATE TONIGHT
THROUGH SUNDAY MORNING. THE WINTRY PRECIP IS EXPECTED TO ARRIVE IN
THE KINL TO KBRD AREAS AFTER 10Z...TRANSLATING EAST TO THE
KHIB/KDLH TERMINALS AROUND 14Z. THE MIX OF -FZRA/SN IS EXPECTED TO
LAST FOR A 2-4 HR PERIOD WITH A LIGHT GLAZE OF ICE ACCUMULATION IN
THE KINL/KHIB/KDLH/KDLH AREAS THROUGH 18Z. AN ADDITIONAL INCH OR
SO OF SNOW IS LIKELY AT KINL AND KHIB. DUE TO MODEL INCONSISTENCY
IN PLACEMENT OF THE PRECIP...AND THE WARMER SFC TEMPS SUNDAY
AFTERNOON...CONFIDENCE IN PTYPE LOWEST IN KHYR AREA.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 34 16 19 6 / 40 10 10 30
INL 36 7 11 -4 / 40 30 20 10
BRD 38 15 18 10 / 40 10 10 70
HYR 37 21 23 8 / 40 10 20 70
ASX 36 21 23 8 / 40 10 10 50
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR MNZ037-038.
WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR MNZ010-011-018-
019-025-026-033>036.
WINTER WEATHER ADVISORY FROM 8 AM THIS MORNING TO 2 PM CST THIS
AFTERNOON FOR MNZ012-020-021.
WI...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR WIZ001-006.
WINTER WEATHER ADVISORY FROM 8 AM THIS MORNING TO NOON CST TODAY
FOR WIZ002-003-007-008.
LS...NONE.
&&
$$
SHORT TERM...GROCHOCINSKI
LONG TERM...MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS RALEIGH NC
948 PM EST MON JAN 13 2014
.SYNOPSIS...A LOW PRESSURE SYSTEM WILL CROSS THE CAROLINAS LATE
TONIGHT AND TUESDAY. AN ARCTIC COLD FRONT WILL CROSS THE REGION ON
WEDNESDAY.
&&
.NEAR TERM /TONIGHT THROUGH TUESDAY MORNING/...
AS OF 948 PM MONDAY...
TONIGHT THROUGH TUESDAY MORNING...
WEAK S/W VORT DISTURBANCES EMBEDDED IN THE SWLY FLOW ALOFT IN
ADVANCE OF AN ELONGATED POSITIVE TILTED S/W TROUGH THAT EXTENDS FROM
SOUTHERN ONTARIO SOUTHWARD INTO THE SOUTHERN PLAINS WILL EJECT NEWD
AND ACROSS THE CAROLINAS OVERNIGHT. BAND OF PRE-FRONTAL SHOWERS IS
JUST NOW STARTING TO FILL IN EAST OF THE MOUNTAINS...TAKING SOME
TIME TO OVERCOME THE DRY AIR IN PLACE(PWATS 0.3-0.5"). WHILE BROAD
MOISTENING WILL SEND PWATS TO 1.0" IN THE WEST TO 1.2" IN THE
EAST...THE STRONG/BETTER LOW-LEVEL MOISTURE TRANSPORT IS FORECAST TO
REMAIN ACROSS SOUTHERN COASTAL SECTIONS OF THE CAROLINAS...IN
PROXIMITY TO A WEAK SFC WAVE DEVELOPING ALONG THE EASTWARD ADVANCING
COLD FRONT. THIS WILL RESULT IN VERY LIGHT RAINFALL AMOUNTS MUCH OF
THE FORECAST AREA WITH ALL OF THE HI-RES CAM MODELS AND RAP SHOWING
THE RAIN BAND MOVING EASTWARD IN A WEAKENING/FRAGMENTED STATE.
POPS OVERNIGHT INTO TUESDAY MORNING VARY FROM LOW END LIKELY NW TO
CATEGORICAL GENERALLY ALONG AND EAST OF I-95. MIN TEMPS RELATIVELY
MILD FOR JANUARY...RANGING FROM MID 40S NW TO AROUND SE.
&&
.SHORT TERM /TUESDAY AFTERNOON THROUGH WEDNESDAY NIGHT/...
AS OF 335 PM MONDAY...
TUESDAY AFTERNOON AND TUESDAY NIGHT...
MID LEVEL TROUGH AND ASSOCIATED SFC BOUNDARY WILL CROSS CENTRAL
NC TUESDAY MORNING...EXITING OUR COASTAL PLAIN COUNTIES EARLY TUESDAY
AFTERNOON. W-NW WINDS BEHIND THE EXITING TROUGH WILL ADVECT DRIER
STABLE AIR INTO OUR REGION. THE ARRIVAL OF THIS AIRMASS WILL AID TO
DIMINISH SHOWER COVERAGE WEST-TO-EAST ACROSS CENTRAL NC. THIS
DECREASING POP TREND WILL OCCUR IN THE WESTERN PIEDMONT BY LATE
MORNING...PROGRESSING INTO THE COASTAL PLAIN BY MID AFTERNOON.
APPEARS THAT SKIES MAY BE ABLE TO CLEAR OUT IN THE WESTERN PIEDMONT
TO ALLOW FOR PARTIAL SUNSHINE WITH MOSTLY CLOUDY SKIES EAST AND
PARTIAL SUN WEST SHOULD YIELD A UNIFORM MAX TEMPS FILED TUESDAY.
DOWNSLOPE WARMING DUE TO W-NW LOW LEVEL FLOW WILL OFFSET INITIAL
COLD AIR ADVECTION. MAX TEMPS UPPER 50S NW TO LOWER 60S SE.
DRIER AND NOTICEABLY COOLER AIRMASS WITH WEAK SFC RIDGE QUICKLY
TRANSLATING EAST. MIN TEMPS GENERALLY IN THE MID 30S.
WEDNESDAY AND WEDNESDAY NIGHT...
LATEST GFS/ECMWF HAVE COME INTO DECENT AGREEMENT WITH THEIR DEPICTION
OF A DEEP L/W TROUGH INITIALLY EXTENDING FROM THER GREAT LAKES SWD
INTO THE DEEP SOUTH...ADVANCING INTO THE CAROLINAS BY EARLY THURSDAY.
A S/W ROUNDING THE BASE OF THE TROUGH WILL LIFT NEWD ALONG THE SPINE
OF THE APPALACHIANS WEDNESDAY. THIS FEATURE WILL INDUCE THE FORMATION
OF A SFC TROUGH IN THE LEE OF THE MOUNTAINS WITH A SFC WAVE OVER WESTERN
NC. THE EXPECTED TRACK OF THE S/W AT THIS TIME SUGGEST THE BEST CHANCE FOR
PRECIP WILL BE IMMEDIATELY WEST OF OUR REGION...MORE SO IN THE MOUNTAINS.
ONCE THIS S/W LIFTS NWD INTO THE CENTRAL APPALACHIANS...AN ARCTIC COLD
FRONT WILL SWEEP ACROSS OUR REGION WEDNESDAY AFTERNOON. SINCE IT NOW
APPEARS THAT THE PIEDMONT WILL BE ON THE WARM SECTOR OF THE LOW...
ANY SHOWERS THAT OCCUR SHOULD BE MAINLY LIQUID. BEHIND THE BOUNDARY...
POTENTIAL FOR A FEW SNOWFLAKES TO MIX IN WITH THE RAIN SHOWERS AS THE
COLDER AIR ALOFT BECOMES DEEPER/CLOSER TO THE SURFACE.
BEST FORCING FOR RAIN SHOWERS APPEAR TO BE ACROSS THE NW-NORTHERN
PIEDMONT WITH SHALLOWER MOISTURE AND LIFT FARTHER SOUTH. WILL VARY
POPS FROM CHANCE NW TO SLIGHT CHANCE SOUTH. DID ADJUST MAX TEMPS UP
3-5 DEGREES FROM PREVIOUS FORECAST DUE TO SLOWER FRONTAL PASSAGE.
MAX TEMPS MID 40S NW TO LOWER 50S SE. IF RAIN SHOWERS HOLD OFF AND
FRONTAL PASSAGE BECOMES SLOWER...MAX TEMPS MAY NEED TO BE RAISED
ANOTHER 3-5 DEGREES.
AS THE S/W APPROACHES THE COAST WEDNESDAY NIGHT...ANOTHER SURFACE
LOW WILL DEVELOP AND STRENGTHEN OFFSHORE. THE WRAP AROUND FROM THIS
SYSTEM MAY CAUSE A FEW SNOW SHOWERS ACROSS THE NORTHERN HALF OF THE
COASTAL PLAIN AND POSSIBLY AS FAR WEST AS THE TRIANGLE AREA. THE
ECMWF STILL FAVORS A MORE INLAND INFLUENCE COMPARED TO THE GFS WHICH
REMAINS VERY PROGRESSIVE. CONSIDERING THE PROBABLE BAROCLINICITY
THAT MAY EXIST OFFSHORE...LEANED TOWARD THE ECMWF. THUS EXPECT A FEW
SNOW SHOWERS BUT NOT ENOUGH AT THIS TIME TO RAISE ANY CONCERNS. MIN
TEMPS MID 20S WHERE SKIES WILL CLEAR OFF EARLY IN THE EVENING TO
NEAR 30 IN THE EAST.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 335 PM MONDAY...
THURSDAY AND THURSDAY NIGHT...
BROAD UPPER TROUGH WILL AMPLIFY/DIG SWD AS A POTENT S/W ADVANCES
SEWD ON THE BACK SIDE OF THE TROUGH. THIS WILL CAUSE THE MID-UPPER
FLOW TO BACK TO A SW DIRECTION AND ADVECT MOISTURE INTO OUR REGION
BY THURSDAY EVENING...MAINLY IN THE UPPER REACHES OF THE ATMOSPHERE.
CLEAR TO PARTLY CLOUDY SKIES EARLY THURSDAY SHOULD BECOME PARTLY-
MOSTLY CLOUDY BY LATE IN THE DAY AND INTO THURSDAY NIGHT. PRESENCE
OF STRONG UPPER TROUGH WILL HOLD COOL AIRMASS IN PLACE. MAX TEMPS
THURSDAY MAINLY IN THE LOW-MID 40S. MIN TEMPS THU NIGHT IN THE UPPER
20S-LOWER 30S. -WSS
FRIDAY THROUGH MONDAY: ANOTHER POTENT DIGGING S/W ALOFT WILL HELP
AMPLIFY THE MID LEVEL TROUGH OVER THE EASTERN U.S. AGAIN ON
FRIDAY... AND SEND ANOTHER COLD FRONT ACROSS OUR AREA FRIDAY INTO
FRIDAY EVENING. MEDIUM RANGE MODELS CONTINUE TO STRUGGLE WITH REGARD
TO THE AMPLIFICATION AND TIMING OF THIS MID LEVEL TROUGH THOUGH. THE
GFS AND MOST OF ITS ENSEMBLE MEMBERS KEEP US DRY WITH THIS SYSTEM.
HOWEVER... THE LAST FEW RUNS OF THE OPERATIONAL ECMWF ARE SHOWING
SOME PRECIP WITH THIS SYSTEM... ALONG AND BEHIND THE COLD FRONT...
WITH SOME OF THE PRECIP FALLING AS SNOW. FOR NOW WILL ONLY INTRODUCE
A SLIGHT CHANCE OF PRECIP LATE FRIDAY INTO FRIDAY NIGHT GIVEN THE
UNCERTAINTY. DRY WEATHER IS EXPECTED TO RETURN FOR NEXT WEEKEND...
ALTHOUGH TEMPS ARE EXPECTED TO BE BELOW NORMAL... GENERALLY IN THE
30S AND 40S (ESPECIALLY ON SATURDAY). WITH SURFACE HIGH PRESSURE
MOVING ACROSS THE NORTHERN GULF OF MEXICO LATE SUNDAY INTO MONDAY...
TEMPS ARE EXPECTED TO WARM BACK TO NORMAL FOR MONDAY. -BSD
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
AS OF 700 PM MONDAY...
VFR CONDITIONS CURRENTLY OBSERVED ACROSS CENTRAL NC.
HOWEVER...PRECIPITATION ASSOCIATED WITH AN APPROACHING UPPER LEVEL
DISTURBANCE WILL SPREAD ACROSS THE AREA FROM THE SOUTHWEST TONIGHT.
WHILE THE LEADING EDGE OF THE PRECIP IS MOSTLY WEST OF THE
MOUNTAINS...ADDITIONAL PRECIP SHOULD DEVELOP AND SPREAD INTO THE
AREA FROM THE SOUTH. PRECIP AND LOW CLOUDS SHOULD REACH
KGSO/KINT/KFAY BETWEEN 05-08Z...SPREADING NORTHEAST THE MORNING
HOURS. PRECIP WILL BE HEAVIER AND MORE WIDESPREAD OVER EASTERN
NC...WHERE THERE IS HIGHER CONFIDENCE IN IFR AND/OR LIFR CONDITIONS
BY 12Z TUESDAY. AT KGSO AND KINT...LIGHTER PRECIP MAY ALLOW
CEILINGS TO REMAIN MVFR WITH A SHORTER PERIOD OF POSSIBLE IFR
CEILINGS.
AVIATION CONDITIONS WILL IMPROVE FROM WEST TO EAST TUESDAY AFTERNOON
AND EVENING AS A WESTERLY FLOW DEVELOPS IN THE WAKE OF THIS SYSTEM.
EXPECT VFR CONDITIONS TO RETURN BY THE END OF THE 24 HOUR TAF PERIOD.
OUTLOOK... A COLD FRONT WILL CROSS NC ON WEDNESDAY...BRINGING
ANOTHER PERIOD OF SUB-VFR CONDITIONS AND A CHANCE OF PRECIP. VFR
CONDITIONS ARE THEN EXPECTED ON THURSDAY BEFORE YET ANOTHER SYSTEM
CROSSES THE AREA LATE FRIDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...CBL
SHORT TERM...WSS
LONG TERM...WSS/NP/BSD
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1245 AM EST SUN JAN 12 2014
.SYNOPSIS...
A COLD FRONT WILL APPROACH WILL CROSS THE AREA TONIGHT. HIGH
PRESSURE WILL BUILD IN SUNDAY AND MOVE OFFSHORE MONDAY. LOW PRESSURE
WILL PASS NORTH OF THE AREA LATE TUESDAY DRAGGING A COLD FRONT
THROUGH THE REGION WEDNESDAY. HIGH PRESSURE WILL BRIEFLY BUILD IN
THURSDAY FOLLOWED BY ANOTHER COLD FRONT CROSSING FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1245 AM SUNDAY...COLD FRONT IS MOVING THROUGH THE EASTERN
PIEDMONT AND SHOULD REACH THE COAST OVER THE NEXT SEVERAL HOURS.
WITH RADAR COMPOSITES SHOWING SOME LIGHT SHOWERS ACROSS CENTRAL NC
AND WITH THE RAP AND 4 KM WRF SHOWING SOME LIGHT PRECIP POSSIBLE
OVER EASTERN NC...HAVE MAINTAINED SLIGHT CHC POPS THROUGH THE
EARLY MORNING HOURS. ALL PRECIP SHOULD BE OFFSHORE BY DAYBREAK.
TEMPS FALLING A BIT MORE SLOWLY THAN ANTICIPATED GIVEN THE
SLIGHTLY SLOWER MOVEMENT OF THE FRONT AND HAVE RAISED TEMPS BY A
DEGREE OR TWO FOR OVERNIGHT LOWS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TODAY/...
AS OF 215 PM SAT...HIGH PRES WILL BUILD IN SUNDAY WITH MOSTLY
CLEAR SKIES. GUSTY NW WINDS EARLY WILL GRAD DIMINISH AND BECOME
MORE WESTERLY LATE. HIGHS MAINLY 55 TO 60.
&&
.LONG TERM /TONIGHT THROUGH SATURDAY/...
AS OF 245 PM SATURDAY...A PROGRESSIVE PATTERN WILL CONTINUE
THROUGH THE LONG TERM WITH SEVERAL AMPLIFIED SYSTEMS MOVING
THROUGH THE FLOW ALOFT. HIGH PRES CENTERED OVER THE AREA SUN
EVENING WILL PUSH OFFSHORE LATE SUN NIGHT AND MON AS A ROBUST
SHORTWAVE TROUGH DIGS INTO THE SOUTHERN PLAINS. MODELS QUICKLY
DAMPEN THE SHORTWAVE AS IT LIFTS NE ACROSS THE AREA AND HAVE
SHIFTED THE LOW PRES CENTER FARTHER SOUTH FROM PREVIOUS RUNS...THE
MORE PROGRESSIVE AND DRIER GFS NOW OFF THE SE COAST AND WETTER
ECMWF ALONG THE SC/NC COAST. CONTINUE TO FAVOR THE ECMWF THROUGH
MUCH OF THE LONG TERM WITH PRECIP CHANCES INCREASING ACROSS THE
AREA MON NIGHT AND CONTINUING INTO TUES WITH THE COLD FRONT
PROGGED TO PUSH THROUGH TUES AFTERNOON. ALTHOUGH MODELS STILL
INDICATING STRONG LOW LEVEL SHEAR WILL BE IN PLACE...SEVERE
CHANCES APPEAR MINIMAL AT THIS TIME AS MODELS DEPICTING POSITIVE
LI`S ACROSS THE REGION. SOUTHERLY FLOW BRINGS ABOVE NORMAL TEMPS
MON THROUGH TUE WITH HIGHS IN THE 60S AND LOWS IN THE 40S.
A LONGWAVE UPPER TROUGH WILL REMAIN ACROSS THE EASTERN CONUS TUES
NIGHT WITH ANOTHER ROBUST UPPER TROUGH AND COLD FRONT PROGGED TO
PUSH ACROSS THE REGION WED AND WED NIGHT. FORCING AHEAD OF THIS
TROUGH COULD BRING ADDITIONAL RAIN CHANCES WED BUT MOISTURE WILL
BE LIMITED AND QPF AMOUNTS EXPECTED TO BE LIGHT. THE UPPER TROUGH
QUICKLY PUSHES OFFSHORE EARLY THURS WITH SHORTWAVE RIDGING AND SFC
HIGH PRES BRIEFLY BUILDING IN THURS. CYCLONIC FLOW RETURNS ALOFT
THURS NIGHT AND FRI WITH THE SFC HIGH PRES SLIDES OFFSHORE AHEAD
OF THE NEXT FRONTAL SYSTEM. MOISTURE LOOKS RATHER LIMITED WITH
THIS NRN STREAM SYSTEM AS WELL WITH MAINLY A DRY FRONTAL PASSAGE
FRI NIGHT. TEMPS AT OR SLIGHTLY BELOW SEASONAL NORMS LATE IN THE
WEEK WITH HIGHS IN THE MID 40S TO MID 50S AND LOWS IN THE UPPER
20S INLAND TO 30S COAST.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
SHORT TERM /THROUGH SUNDAY EVENING/...
AS OF 1245 AM SUN...MVFR CEILINGS EXPECTED AHEAD OF COLD FRONT
OVER THE NEXT FEW HOURS GIVEN A MOIST BOUNDARY LAYER. SKIES SHOULD
BECOME CLEAR BY DAYBREAK. SKC EXPECTED SUNDAY WITH WESTERLY WINDS
GUSTING 15-20 KNOTS DURING THE AFTERNOON.
LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 245 PM SATURDAY...VFR CONDITIONS SHOULD PREVAIL SUNDAY NIGHT
THROUGH MONDAY NIGHT WITH HIGH PRES RIDGING INTO THE AREA. LOW-LEVEL
MOISTURE INCREASES WITH SOME SUB-VFR CONDITIONS POSSIBLE IN
SCATTERED LIGHT SHOWERS LATE MONDAY NIGHT INTO TUESDAY. COLDER AND
DRIER AIR RETURNS FOR MIDWEEK AND ALTHOUGH SOME ISOLATED SHOWERS MAY
ACCOMPANY A SECONDARY FRONTAL PASSAGE ON WEDS...ALTHOUGH EXPECT VFR
CONDITIONS TO PREVAIL.
&&
.MARINE...
SHORT TERM /THROUGH SUNDAY/...
AS OF 1245 AM SUNDAY...WINDS REMAIN SW BUT SHOULD VEER TO NW AS
COLD FRONT PASSES OVER THE NEXT FEW HOURS AND WITH STRONG
CAA...WIND SPEEDS SHOULD INCREASE TO 20 TO 25 KNOT OVER THE
COASTAL WATERS AND SOUNDS BY MORNING. ON SUNDAY THE NW WINDS WILL
GRAD DIMINISH AND BECOME W 10 TO 15 KT LATE. SEAS...WHICH ARE
CURRENTLY IN THE 6 TO 8 FOOT RANGE...SHOULD GRADUALLY DROP BELOW 6
FEET FOR ALL BUT THE OUTER CNTRL WTRS BY LATE SUNDAY.
LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 245 PM SATURDAY...LIGHT WINDS EXPECTED SUN NIGHT WITH HIGH
PRES OVER THE AREA. WINDS WILL BECOME S/SW UP TO 15-20 KT MON
AHEAD OF THE NEXT FRONTAL SYSTEM WHILE SEAS WILL REMAIN AROUND 3-5
FT. WINDS/SEAS INCREASE FURTHER LATE MON NIGHT TUE JUST AHEAD OF
THE FRONT...UP TO 25 KT WITH SEAS AROUND 4-7 FT. SOME TIMING
DIFFERENCES AMONG THE MODELS FOR THE FRONTAL PASSAGE WITH THE MORE
PROGRESSIVE GFS PUSHING THE FRONT THROUGH EARLY IN THE DAY...BUT
THE PREFERRED ECMWF AND NAM DELAY FROPA UNTIL LATE AFTERNOON/EARLY
EVENING. WINDS BECOME W 5-15 KT TUE NIGHT WITH SEAS SUBSIDING TO
3-5 FT. WINDS QUICKLY BACK TO SW AND INCREASE TO 15-25 KT WED
AHEAD OF A SECONDARY FRONT PROGGED TO MOVE ACROSS THE WATERS WED
AFTERNOON/EVENING. STRONGER CAA BEHIND THIS FRONT WILL KEEP WINDS
ELEVATED...NW AROUND 15-25 KT...INTO THURS MORNING. SEAS GENERALLY
3-6 FT WED INTO THURS MORNING. WINDS DIMINISH SOME THURS
AFTERNOON...THEN BACK TO SW AROUND 10-20 KT THURS NIGHT WITH SEAS
GENERALLY 2-5 FT.
&&
.CLIMATE...
ACCORDING TO OUR 530 PM CLIMATE DATA...CAPE HATTERAS HAS TIED THE
PREVIOUS HIGH TEMPERATURE RECORD OF 70 DEGREES ORIGINALLY SET IN
1890.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EST THIS MORNING FOR AMZ130-
135.
SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR AMZ152-
154.
SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR AMZ150-
156-158.
&&
$$
SYNOPSIS...RF
NEAR TERM...CTC
SHORT TERM...RF
LONG TERM...SK
AVIATION...CTC/SK/DAG
MARINE...CTC/RF/SK/DAG/BM
CLIMATE...BM
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
219 AM CST SUN JAN 12 2014
.UPDATE...
ISSUED AT 220 AM CST SUN JAN 12 2014
WE ARE GETTING SOME ICING REPORTS ENTERING THE WESTERN FORECAST
AREA...AND RADAR RETURNS ARE INCREASING. THE RAP SEEMS TO
INITIALIZE WELL...AND BRINGS FREEZING RAIN FROM WEST TO EAST
THROUGH 15Z...AFFECTING AREAS ALONG AND SOUTH OF HIGHWAY 2. WE
HAVE ISSUED A FREEZING RAIN ADVISORY FOR THIS HAZARD.
UPDATE ISSUED AT 1151 PM CST SAT JAN 11 2014
WARM ADVECTION PRECIPITATION CONTINUES TO MOVE EAST. RADAR INDICATED
VERY LIGHT FREEZING RAIN IN WESTERN/CENTRAL ND. TEMPERATURES
CONTINUE TO RISE FROM THE WEST AS WELL AS INCREASING SOUTH/SOUTHWEST
WINDS OVERNIGHT. OVERNIGHT LOWS SHOULD HAVE ALREADY OCCURRED THIS
EVENING. PRECIPITABLE WATER RISES TO BETTER THAN HALF AN INCH
OVERNIGHT THEN DECREASES FROM THE WEST IN THE MORNING. NO CHANGES
THIS UPDATE.
UPDATE ISSUED AT 1000 PM CST SAT JAN 11 2014
UPPER AIR PATTERN FORECAST TO BE QUITE PROGRESSIVE NEXT COUPLE DAYS.
UPPER LEVEL RIDGE AXIS WAS LOCATED OVER THE CENTRAL DAKOTAS AND WILL
MOVE INTO SOUTHEAST CANADA BY SUN AFTERNOON.
PATCHY FOG HAD DEVELOPED OVER MN SIDE OF THE RED RIVER. HOWEVER MID
LEVEL CLOUDS WERE THICKENING ON THE MN SIDE AND VISIBILITIES WERE
INCREASING. WILL NOT MENTION ANY PATCHY FOG.
BIS OBSERVED SOUNDING INDICATED MOIST LAYER MOVING IN AROUND 600-700
HPA AND RELATIVELY DRY ATMOSPHERE BELOW 700 HPA. SOME PRECIPITATION
HAS BEEN REPORTED IN WESTERN ND. HOWEVER ONLY TRACE AMOUNTS HAVE
BEEN REPORTED. CLOUD CEILINGS REMAINS ABOVE 6 TO 7 THOUSAND FT.
NO PLANS TO ISSUE AN ADVISORY UNLESS CONDITIONS DETERIORATE.
UPDATE ISSUED AT 702 PM CST SAT JAN 11 2014
TEMPERATURES ARE FALLING QUICKLY WHERE EITHER A CLEAR OR THIN CIRRUS
WAS OVER THE AREA. WILL RAISE TEMPS A BIT IN THE FAR WESTERN ZONES.
WILL LOWER TEMPS FROM NEAR LANGDON TO NEAR PKD.
AREA RADARS INDICATED LIGHT PRECIPITATION IN WESTERN ND BUT DOES NOT
APPEAR TO BE REACHING THE GROUND. NO OBS SITE REPORTED PRECIP IN THE
WESTERN ND. MODELS MAINTAIN A DRY LAYER BETWEEN ABOUT 7 THOUSAND
FT AND THE SURFACE. SO WILL HOLD OFF ANY ANY ADVISORIES AT THIS
TIME OR FREEZING RAIN. WILL RE-EVALUATE AT 10 PM UPDATE.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 346 PM CST SAT JAN 11 2014
THE MAIN CHALLENGE WILL BE FAST MOVING SYSTEMS IN NW FLOW
ALOFT...PRECIP TYPE AND WIND SPEEDS THROUGH THE FORECAST. MODELS
ARE IN GENERAL AGREEMENT AND A GFS/ECMWF BLEND WAS USED FOR THIS
FORECAST.
FOR TONIGHT...STRONG WAA WILL BEGIN AT ALL LEVELS AS A POTENT
SHORTWAVE FROM THE PACIFIC NW MOVES THROUGH THE REGION. THERE
SHOULD BE A BAND OF FREEZING RAIN/SLEET WITH TEMPS ALOFT WELL
ABOVE 0C...BUT NOT EXPECTING TOO MUCH QPF GIVEN FAST MOVEMENT OF
SYSTEM. EXPECTING THE PCPN TO CREATE VERY ICY CONDITIONS BY
SUNDAY MORNING...AND HAS BEEN HIGHLIGHTED IN THE SPS.
ON SUNDAY...THERE SHOULD BE SOME MORNING FREEZING RAIN/RAIN MAINLY
IN THE SOUTH...THEN IT WILL BE VERY MILD WITH ALL AREAS ABOVE
FREEZING. IT COULD REACH THE UPPER 30S IN THE SOUTH WITH
FAVORABLE FLOW AS STRONG LOW PRESSURE PASSES NORTH OF THE REGION
ACROSS SOUTHERN CANADA.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 346 PM CST SAT JAN 11 2014
FOR MONDAY AND MON NIGHT...IT SHOULD BE COOLER THAN RECENT DAYS WITH
TEMPS STRUGGLING TO REACH 10 ABOVE IN MOST AREAS. TEMPS COULD EVEN
BE A BIT COOLER THAN FCST. OTHERWISE...SOME LIGHT SNOW IS POSSIBLE
WITH A CLIPPER TYPE SYSTEM MOVING THROUGH THE REGION...WITH PERHAPS
AN INCH OR 2 OF SNOW POSSIBLE.
TUESDAY NIGHT THROUGH SATURDAY...12 UTC GFS/ECMWF IN VERY GOOD
AGREEMENT BOTH SHOWING A STRONG NORTHERN PACIFIC SHORT-WAVE BREAKING
DOWN AND MOVING THROUGH THE WESTERN NOAM RIDGE...IMPACTING THE
NORTHERN PLAINS WED/THURS. WARM FRONT WILL PUSH ACROSS THE FORECAST
AREA WEDNESDAY WITH 850 HPA TEMPERATURES RISING WELL ABOVE ZERO
CELSIUS IN ITS WAKE. MODELS PAINT THE MAJORITY OF FRONTAL
PRECIPITATION ACROSS THE NORTHERN VALLEY INTO NORTH-CENTRAL MN...
BUT THERMAL PROFILES ARE FAVORABLE FOR FREEZING RAIN SO WILL ADD
MIXED PRECIPITATION TO WEATHER GRIDS WEDNESDAY AFTERNOON AND
EVENING. ANY PRECIPITATION WILL CHANGE OVER TO SNOW WEDNESDAY NIGHT
WITH COLD FRONTAL PASSAGE...BUT BIGGER IMPACT WILL BE VERY STRONG
NORTHWESTERLY WIND. GFS/ECMWF BOTH SHOW 40 TO 50 KTS AT 925 HPA
WEDNESDAY NIGHT AND THURSDAY ALONG AND WEST OF THE VALLEY AS THE
PRIMARY SURFACE LOW MOVES ACROSS SOUTHERN ONTARIO. THERE MAY NOT BE
MUCH FALLING SNOW CONCURRENT WITH THE HIGHEST WIND SPEEDS...BUT IT
MAY BE STRONG ENOUGH TO STILL CREATE HEADACHES AT THE SURFACE WITH
BLOWING AND DRIFTING SNOW. SOMETHING TO WATCH CAREFULLY OVER THE
NEXT SEVERAL DAYS. FRIDAY/SATURDAY WILL BE DRY.
TEMPERATURE-WISE...AFTERNOON HIGHS WILL PEAK IN THE MID 20S TO LOWER
30S ON WEDNESDAY IN THE SYSTEM/S WARM SECTOR WITH COOLER CONDITIONS
FOR THE LATTER HALF OF THE WEEK. BY FRIDAY EXPECT HIGHS GENERALLY IN
THE TEENS WITH MORNING LOWS IN THE SINGLE DIGITS BELOW ZERO. A
SLIGHT WARM-UP WILL COMMENCE FOR THE BEGINNING OF THE WEEKEND AS THE
WESTERN NOAM RIDGE REASSERTS ITSELF ACROSS THE CONTINENT/S MID-
SECTION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1151 PM CST SAT JAN 11 2014
FOG LOOP INDICATED THE TRAILING EDGE OF IFR/MVFR CIGS OVER NORTHEAST
ZONES WERE MOVING NORTHEAST AROUND 5 KNOTS. MUCH OF CLOUD DECK IS
NOW OBSCURED BY HIGHER CLOUDS ON LOOP. FEW CIGS AROUND 25 HUNDRED FT
WERE AT CAVALIER ND OTHERWISE MOST SITES ARE ABOVE 5 THOUSAND FT IN
THE NORTHWESTERN ZONES TO 12 THOUSAND FT IN THE SOUTHERN ZONES.
EXPECT IFR/MVFR CIGS TO CONTINUE SLOWLY MOVING NORTHEAST. REST OF
THE AREA SHOULD HAVE VFR CIGS THROUGH SUNRISE EXCEPT NEAR RAIN
SHOWERS. SOME CLEARING EXPECTED SUN MORNING.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...FREEZING RAIN ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
NDZ024-026>030-038-039-049-052-053.
MN...FREEZING RAIN ADVISORY UNTIL 9 AM CST THIS MORNING FOR MNZ009-
013>017-022>024-027-028-030>032-040.
FREEZING RAIN ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
MNZ001>003-029.
&&
$$
UPDATE...DK
SHORT TERM...HOPKINS
LONG TERM...ROGERS
AVIATION...HOPPES
AREA FORECAST DISCUSSION
NWS NORMAN OK
1136 AM CST SUN JAN 12 2014
.DISCUSSION...
AVIATION DISCUSSION FOR THE 18Z TAFS IS BELOW.
&&
.AVIATION...
VFR CONDITIONS ARE EXPECTED TO CONTINUE. THE MAIN CONCERN
IS STRONG WINDS MAINLY BEFORE 00Z. NO SIGNIFICANT CHANGES
WERE MADE TO THE TAFS.
THE STRONGEST WINDS WILL REMAIN SOUTHEAST OF KEND-KCDS
THROUGH 00Z WITH A FEW GUSTS NEAR 40 KT. NON CONVECTIVE
LOW LEVEL WIND MAY BE OCCURRING IN THESE LOCATIONS
SOUTHEAST OF KEND-KCDS...BUT DID NOT MENTION DUE TO
LOW CONFIDENCE AS STRONGER WINDS 1000-2000 FT AGL
APPEAR TO BE MIXING DOWN TO THE GROUND.
A COLD FRONT WILL MOVE SOUTHEAST AND THROUGH ALL SITES
21-05Z. THINK FRONTAL PASSAGE WILL BE NEAR 02-04Z AT
KOKC...KLAW...AND KSPS. A WIND SHIFT TO THE NORTH AND
NORTHWEST WILL OCCUR WITH THE FRONT.
MBS
&&
.PREV DISCUSSION... /ISSUED 1046 AM CST SUN JAN 12 2014/
DISCUSSION...
A MILD AND WINDY DAY IS IN PROGRESS ACROSS THE SOUTHERN PLAINS.
FIRE WEATHER REMAINS THE MAIN CONCERN...AS RELATIVE HUMIDITY
VALUES CONTINUE TO PLUMMET. WE EXPECT THE HUMIDITY TO DROP BELOW
20 PERCENT ACROSS MOST OF WESTERN OKLAHOMA AND WESTERN NORTH TEXAS
BY MID-AFTERNOON...WHILE TEMPERATURES CLIMB INTO THE 70S OVER THIS
SAME AREA. MEANWHILE...THE SOUTHWEST WINDS WILL CONTINUE WITH
LITTLE CHANGE THIS AFTERNOON...OTHER THAN PERHAPS A SLIGHT
DECREASE IN THE NORTHWEST PARTS OF OKLAHOMA...WHERE THE PROXIMITY
OF THE FRONT WILL REDUCE THE PRESSURE GRADIENT SLIGHTLY.
THE LATEST SHORT-TERM MODEL GUIDANCE AND ACTUAL OBSERVATIONS
GENERALLY SUPPORT OUR CURRENT FORECAST WITH NO SIGNIFICANT
CHANGES. SO...NO UPDATE IS PLANNED FOR THIS MORNING.
PREV DISCUSSION... /ISSUED 546 AM CST SUN JAN 12 2014/
AVIATION...
12/12Z TAFS...VFR CONDITIONS WILL PREVAIL. LLWS WILL BE SEEN FIRST
3 OR 4 HOURS ACROSS ALL BUT NORTHWEST OKLAHOMA TERMINALS. STRONG
SOUTHWEST WINDS WILL OCCUR AHEAD OF COLD FRONT. FROPA EXPECTED
NORTHWEST OKLAHOMA TERMINALS AROUND 22Z WITH SOUTHWARD PROGRESSION
CLEARING ALL TERMINALS BY 13/04Z.
PREV DISCUSSION... /ISSUED 422 AM CST SUN JAN 12 2014/
DISCUSSION...
VERY WARM...DRY...AND WINDY CONDITIONS ACROSS THE REGION TODAY. WE
WENT WITH THE RAP MODEL FOR SHORT-TERM FORECAST SOLUTION WHICH
SPREADS RED FLAG WILDFIRE CONDITIONS ACROSS A LARGE PART OF
WESTERN OKLAHOMA AND WESTERN NORTH TEXAS. THIS SOLUTION IS MUCH
DRIER THAN OTHER GUIDANCE AND WILL LIKELY BE CLOSER TO VERIFYING
GIVEN STRONG DOWNSLOPE COMPONENT TO FLOW AND UPSTREAM DRY AIR ON
REGIONAL SOUNDINGS. THERE VERY WELL COULD BE FAIRLY TIGHT MOISTURE
GRADIENT LATE TODAY JUST EAST OF INTERSTATE-44 CORRIDOR. THIS WILL
BE WATCHED CLOSELY...AND IF NEED BE...ADJUSTMENTS TO CURRENT RED
FLAG WARNING WILL BE MADE. ALTHOUGH IT WILL BE WINDY AND WARM
ACROSS CENTRAL AND SOUTHERN PARTS OF OKLAHOMA... WHICH WILL STILL
CREATE WILDFIRE CONCERNS...CURRENT HUMIDITY FORECAST EXPECTED TO
KEEP OKC AND POINTS SOUTH AND EAST OUTSIDE OF RED FLAG CRITERIA.
WITH ALL OF THAT BEING TYPED...OUTDOOR BURNING AND OTHER ACTIVITIES
THAT COULD LEAD TO WILDFIRES IS DISCOURAGED ACROSS ALL OF OKLAHOMA
AND WESTERN NORTH TEXAS. THERE ARE BURN BANS IN EFFECT ACROSS
NORTH TEXAS.
COLD FRONT WILL MOVE INTO NORTHERN OKLAHOMA MID-LATE
AFTERNOON...WHICH WILL EFFECTIVELY WEAKEN THE PRESSURE GRADIENT
AND ALLOW WINDS TO DECREASE. ALTHOUGH THEY COULD SEE WIND ADVISORY
WORTHY WINDS BRIEFLY LATE THIS MORNING OR EARLY AFTERNOON...THEY
WERE LEFT OUT OF WIND ADVISORY. THIS FRONT WILL BRING IN MUCH
COLDER AIR...WHEN COMPARED TO WHAT WE WILL SEE TODAY. WITH
NUMEROUS COLD FRONTS PASSING OVER THE REGION THROUGH THE WEEK...
TEMPERATURES ARE EXPECTED TO REMAIN NEAR OR SLIGHTLY ABOVE AVERAGE
FOR THE MOST PART. DRY WEATHER EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 70 34 60 32 / 0 10 0 0
HOBART OK 73 32 59 29 / 0 10 0 0
WICHITA FALLS TX 76 35 63 32 / 0 10 0 0
GAGE OK 69 29 59 26 / 0 10 0 0
PONCA CITY OK 67 31 59 31 / 0 10 0 0
DURANT OK 70 42 62 36 / 0 10 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR OKZ013-016>047-050-
051.
RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR OKZ014-016-
021>023-027-033>039-044-045.
TX...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR TXZ083>090.
RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR TXZ083>090.
&&
$$
23/17/17
AREA FORECAST DISCUSSION
NWS NORMAN OK
1046 AM CST SUN JAN 12 2014
.DISCUSSION...
A MILD AND WINDY DAY IS IN PROGRESS ACROSS THE SOUTHERN PLAINS.
FIRE WEATHER REMAINS THE MAIN CONCERN...AS RELATIVE HUMIDITY
VALUES CONTINUE TO PLUMMET. WE EXPECT THE HUMIDITY TO DROP BELOW
20 PERCENT ACROSS MOST OF WESTERN OKLAHOMA AND WESTERN NORTH TEXAS
BY MID-AFTERNOON...WHILE TEMPERATURES CLIMB INTO THE 70S OVER THIS
SAME AREA. MEANWHILE...THE SOUTHWEST WINDS WILL CONTINUE WITH
LITTLE CHANGE THIS AFTERNOON...OTHER THAN PERHAPS A SLIGHT
DECREASE IN THE NORTHWEST PARTS OF OKLAHOMA...WHERE THE PROXIMITY
OF THE FRONT WILL REDUCE THE PRESSURE GRADIENT SLIGHTLY.
THE LATEST SHORT-TERM MODEL GUIDANCE AND ACTUAL OBSERVATIONS
GENERALLY SUPPORT OUR CURRENT FORECAST WITH NO SIGNIFICANT
CHANGES. SO...NO UPDATE IS PLANNED FOR THIS MORNING.
&&
.PREV DISCUSSION... /ISSUED 546 AM CST SUN JAN 12 2014/
AVIATION...
12/12Z TAFS...VFR CONDITIONS WILL PREVAIL. LLWS WILL BE SEEN FIRST
3 OR 4 HOURS ACROSS ALL BUT NORTHWEST OKLAHOMA TERMINALS. STRONG
SOUTHWEST WINDS WILL OCCUR AHEAD OF COLD FRONT. FROPA EXPECTED
NORTHWEST OKLAHOMA TERMINALS AROUND 22Z WITH SOUTHWARD PROGRESSION
CLEARING ALL TERMINALS BY 13/04Z.
PREV DISCUSSION... /ISSUED 422 AM CST SUN JAN 12 2014/
DISCUSSION...
VERY WARM...DRY...AND WINDY CONDITIONS ACROSS THE REGION TODAY. WE
WENT WITH THE RAP MODEL FOR SHORT-TERM FORECAST SOLUTION WHICH
SPREADS RED FLAG WILDFIRE CONDITIONS ACROSS A LARGE PART OF
WESTERN OKLAHOMA AND WESTERN NORTH TEXAS. THIS SOLUTION IS MUCH
DRIER THAN OTHER GUIDANCE AND WILL LIKELY BE CLOSER TO VERIFYING
GIVEN STRONG DOWNSLOPE COMPONENT TO FLOW AND UPSTREAM DRY AIR ON
REGIONAL SOUNDINGS. THERE VERY WELL COULD BE FAIRLY TIGHT MOISTURE
GRADIENT LATE TODAY JUST EAST OF INTERSTATE-44 CORRIDOR. THIS WILL
BE WATCHED CLOSELY...AND IF NEED BE...ADJUSTMENTS TO CURRENT RED
FLAG WARNING WILL BE MADE. ALTHOUGH IT WILL BE WINDY AND WARM
ACROSS CENTRAL AND SOUTHERN PARTS OF OKLAHOMA... WHICH WILL STILL
CREATE WILDFIRE CONCERNS...CURRENT HUMIDITY FORECAST EXPECTED TO
KEEP OKC AND POINTS SOUTH AND EAST OUTSIDE OF RED FLAG CRITERIA.
WITH ALL OF THAT BEING TYPED...OUTDOOR BURNING AND OTHER ACTIVITIES
THAT COULD LEAD TO WILDFIRES IS DISCOURAGED ACROSS ALL OF OKLAHOMA
AND WESTERN NORTH TEXAS. THERE ARE BURN BANS IN EFFECT ACROSS
NORTH TEXAS.
COLD FRONT WILL MOVE INTO NORTHERN OKLAHOMA MID-LATE
AFTERNOON...WHICH WILL EFFECTIVELY WEAKEN THE PRESSURE GRADIENT
AND ALLOW WINDS TO DECREASE. ALTHOUGH THEY COULD SEE WIND ADVISORY
WORTHY WINDS BRIEFLY LATE THIS MORNING OR EARLY AFTERNOON...THEY
WERE LEFT OUT OF WIND ADVISORY. THIS FRONT WILL BRING IN MUCH
COLDER AIR...WHEN COMPARED TO WHAT WE WILL SEE TODAY. WITH
NUMEROUS COLD FRONTS PASSING OVER THE REGION THROUGH THE WEEK...
TEMPERATURES ARE EXPECTED TO REMAIN NEAR OR SLIGHTLY ABOVE AVERAGE
FOR THE MOST PART. DRY WEATHER EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 70 34 60 32 / 0 10 0 0
HOBART OK 73 32 59 29 / 0 10 0 0
WICHITA FALLS TX 76 35 63 32 / 0 10 0 0
GAGE OK 69 29 59 26 / 0 10 0 0
PONCA CITY OK 67 31 59 31 / 0 10 0 0
DURANT OK 70 42 62 36 / 0 10 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR OKZ013-016>047-050-
051.
RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR OKZ014-016-
021>023-027-033>039-044-045.
TX...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR TXZ083>090.
RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR TXZ083>090.
&&
$$
23/17
AREA FORECAST DISCUSSION
NWS NORMAN OK
546 AM CST SUN JAN 12 2014
.AVIATION...
12/12Z TAFS...VFR CONDITIONS WILL PREVAIL. LLWS WILL BE SEEN FIRST
3 OR 4 HOURS ACROSS ALL BUT NORTHWEST OKLAHOMA TERMINALS. STRONG
SOUTHWEST WINDS WILL OCCUR AHEAD OF COLD FRONT. FROPA EXPECTED
NORTHWEST OKLAHOMA TERMINALS AROUND 22Z WITH SOUTHWARD PROGRESSION
CLEARING ALL TERMINALS BY 13/04Z.
&&
.PREV DISCUSSION... /ISSUED 422 AM CST SUN JAN 12 2014/
DISCUSSION...
VERY WARM...DRY...AND WINDY CONDITIONS ACROSS THE REGION TODAY. WE
WENT WITH THE RAP MODEL FOR SHORT-TERM FORECAST SOLUTION WHICH
SPREADS RED FLAG WILDFIRE CONDITIONS ACROSS A LARGE PART OF
WESTERN OKLAHOMA AND WESTERN NORTH TEXAS. THIS SOLUTION IS MUCH
DRIER THAN OTHER GUIDANCE AND WILL LIKELY BE CLOSER TO VERIFYING
GIVEN STRONG DOWNSLOPE COMPONENT TO FLOW AND UPSTREAM DRY AIR ON
REGIONAL SOUNDINGS. THERE VERY WELL COULD BE FAIRLY TIGHT MOISTURE
GRADIENT LATE TODAY JUST EAST OF INTERSTATE-44 CORRIDOR. THIS WILL
BE WATCHED CLOSELY...AND IF NEED BE...ADJUSTMENTS TO CURRENT RED
FLAG WARNING WILL BE MADE. ALTHOUGH IT WILL BE WINDY AND WARM
ACROSS CENTRAL AND SOUTHERN PARTS OF OKLAHOMA... WHICH WILL STILL
CREATE WILDFIRE CONCERNS...CURRENT HUMIDITY FORECAST EXPECTED TO
KEEP OKC AND POINTS SOUTH AND EAST OUTSIDE OF RED FLAG CRITERIA.
WITH ALL OF THAT BEING TYPED...OUTDOOR BURNING AND OTHER ACTIVITIES
THAT COULD LEAD TO WILDFIRES IS DISCOURAGED ACROSS ALL OF OKLAHOMA
AND WESTERN NORTH TEXAS. THERE ARE BURN BANS IN EFFECT ACROSS
NORTH TEXAS.
COLD FRONT WILL MOVE INTO NORTHERN OKLAHOMA MID-LATE
AFTERNOON...WHICH WILL EFFECTIVELY WEAKEN THE PRESSURE GRADIENT
AND ALLOW WINDS TO DECREASE. ALTHOUGH THEY COULD SEE WIND ADVISORY
WORTHY WINDS BRIEFLY LATE THIS MORNING OR EARLY AFTERNOON...THEY
WERE LEFT OUT OF WIND ADVISORY. THIS FRONT WILL BRING IN MUCH
COLDER AIR...WHEN COMPARED TO WHAT WE WILL SEE TODAY. WITH
NUMEROUS COLD FRONTS PASSING OVER THE REGION THROUGH THE WEEK...
TEMPERATURES ARE EXPECTED TO REMAIN NEAR OR SLIGHTLY ABOVE AVERAGE
FOR THE MOST PART. DRY WEATHER EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 70 34 60 32 / 0 10 0 0
HOBART OK 73 32 59 29 / 0 10 0 0
WICHITA FALLS TX 76 35 63 32 / 0 10 0 0
GAGE OK 69 29 59 26 / 0 10 0 0
PONCA CITY OK 67 31 59 31 / 0 10 0 0
DURANT OK 70 42 62 36 / 0 10 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WIND ADVISORY FROM 10 AM THIS MORNING TO 6 PM CST THIS EVENING
FOR OKZ013-016>047-050-051.
RED FLAG WARNING FROM NOON TODAY TO 6 PM CST THIS EVENING FOR
OKZ014-016-021>023-027-033>039-044-045.
TX...WIND ADVISORY FROM 10 AM THIS MORNING TO 6 PM CST THIS EVENING
FOR TXZ083>090.
RED FLAG WARNING FROM NOON TODAY TO 6 PM CST THIS EVENING FOR
TXZ083>090.
&&
$$
06/11/11
AREA FORECAST DISCUSSION
NWS NORMAN OK
422 AM CST SUN JAN 12 2014
.DISCUSSION...
VERY WARM...DRY...AND WINDY CONDITIONS ACROSS THE REGION TODAY. WE
WENT WITH THE RAP MODEL FOR SHORT-TERM FORECAST SOLUTION WHICH
SPREADS RED FLAG WILDFIRE CONDITIONS ACROSS A LARGE PART OF
WESTERN OKLAHOMA AND WESTERN NORTH TEXAS. THIS SOLUTION IS MUCH
DRIER THAN OTHER GUIDANCE AND WILL LIKELY BE CLOSER TO VERIFYING
GIVEN STRONG DOWNSLOPE COMPONENT TO FLOW AND UPSTREAM DRY AIR ON
REGIONAL SOUNDINGS. THERE VERY WELL COULD BE FAIRLY TIGHT MOISTURE
GRADIENT LATE TODAY JUST EAST OF INTERSTATE-44 CORRIDOR. THIS WILL
BE WATCHED CLOSELY...AND IF NEED BE...ADJUSTMENTS TO CURRENT RED
FLAG WARNING WILL BE MADE. ALTHOUGH IT WILL BE WINDY AND WARM
ACROSS CENTRAL AND SOUTHERN PARTS OF OKLAHOMA... WHICH WILL STILL
CREATE WILDFIRE CONCERNS...CURRENT HUMIDITY FORECAST EXPECTED TO
KEEP OKC AND POINTS SOUTH AND EAST OUTSIDE OF RED FLAG CRITERIA.
WITH ALL OF THAT BEING TYPED...OUTDOOR BURNING AND OTHER ACTIVITIES
THAT COULD LEAD TO WILDFIRES IS DISCOURAGED ACROSS ALL OF OKLAHOMA
AND WESTERN NORTH TEXAS. THERE ARE BURN BANS IN EFFECT ACROSS
NORTH TEXAS.
COLD FRONT WILL MOVE INTO NORTHERN OKLAHOMA MID-LATE
AFTERNOON...WHICH WILL EFFECTIVELY WEAKEN THE PRESSURE GRADIENT
AND ALLOW WINDS TO DECREASE. ALTHOUGH THEY COULD SEE WIND ADVISORY
WORTHY WINDS BRIEFLY LATE THIS MORNING OR EARLY AFTERNOON...THEY
WERE LEFT OUT OF WIND ADVISORY. THIS FRONT WILL BRING IN MUCH
COLDER AIR...WHEN COMPARED TO WHAT WE WILL SEE TODAY. WITH
NUMEROUS COLD FRONTS PASSING OVER THE REGION THROUGH THE WEEK...
TEMPERATURES ARE EXPECTED TO REMAIN NEAR OR SLIGHTLY ABOVE AVERAGE
FOR THE MOST PART. DRY WEATHER EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 70 34 60 32 / 0 10 0 0
HOBART OK 73 32 59 29 / 0 10 0 0
WICHITA FALLS TX 76 35 63 32 / 0 10 0 0
GAGE OK 69 29 59 26 / 0 10 0 0
PONCA CITY OK 67 31 59 31 / 0 10 0 0
DURANT OK 70 42 62 36 / 0 10 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WIND ADVISORY FROM 10 AM THIS MORNING TO 6 PM CST THIS EVENING
FOR OKZ013-016>047-050-051.
RED FLAG WARNING FROM NOON TODAY TO 6 PM CST THIS EVENING FOR
OKZ014-016-021>023-027-033>039-044-045.
TX...WIND ADVISORY FROM 10 AM THIS MORNING TO 6 PM CST THIS EVENING
FOR TXZ083>090.
RED FLAG WARNING FROM NOON TODAY TO 6 PM CST THIS EVENING FOR
TXZ083>090.
&&
$$
06/11
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
934 PM EST MON JAN 13 2014
.SYNOPSIS...
HIGH PRESSURE WILL MOVE OFF THE CAROLINA COAST TONIGHT AS A COLD
FRONT APPROACHES FROM THE MISSISSIPPI AND OHIO RIVER VALLEYS. THIS
COLD FRONT WILL CROSS THE REGION THROUGH TUESDAY MORNING AND MOVES
OFF THE EAST COAST LATE TUESDAY AS ANOTHER MORE SIGNIFICANT COLD
FRONT CROSSES TENNESSEE. EXPECT MAINLY MOUNTAIN SNOW SHOWERS TUESDAY
NIGHT THROUGH WEDNESDAY BEFORE DRY HIGH PRESSURE RETURNS ON THURSDAY.
&&
.NEAR TERM /THROUGH TUESDAY/...
900 PM UPDATE...MADE SOME CHANGES TO OVERNIGHT POPS BASICALLY IN
LINE WITH THINKING PRESENTED AT EARLIER UPDATE. NONE OF THE
AVAILABLE GUIDANCE IS DOING PARTICULARLY WELL WRT THE PRECIP
COVERAGE BUT SO FAR EXTRAPOLATED MOTION IS DOING OK FOR TIMING THE
STRATIFORM RAIN BAND THRU THE AREA. IT SEEMS TO HAVE ENOUGH MOISTURE
AVAILABLE FOR IT TO BE MAINTAINED ACRS THE PIEDMONT. A NOTABLE LULL
IS LIKELY AFTER THIS BAND PASSES...BUT SHOWERS CONTINUE WEST OF THE
MTNS IN ZONE OF DPVA AND BETTER MIDLEVEL LAPSE RATES ASSOCIATED WITH
THE UPPER TROUGH. SOME OF THE CONVECTION ALLOWING MODELS AND THE RAP
DO SUGGEST SHOWER ACTIVITY FOLLOWING THE DEPARTURE OF THE BAND. THIS
LOOKS APPROPRIATE WITH THE TROUGH AND ITS EFFECTS MOVING EAST INTO
OUR AREA. TEMPS HAVE BEEN UPDATED OVERNIGHT...WITH TRENDS NEARLY
STEADY UNDER THE CLOUDS. WITH LATEST PROG SOUNDINGS STILL INDICATING
SATURATION IN SNOW GROWTH ZONE...SNOW STILL INCLUDED AT HIGH
ELEVATIONS TONIGHT WHERE SFC TEMPS SUFFICIENTLY CLOSE TO FREEZING.
SLIGHT ADJUSTMENTS TO QPF WERE MADE TO BETTER REFLECT POP
DISTRIBUTION ACRS THE CWFA...THOUGH SNOW TOTALS MOSTLY REMAIN UNDER
AN INCH.
630 PM UPDATE...AS UPPER TROUGH CONTINUES TO SWING INTO THE LOWER
MISSISSIPPI VALLEY...THE PREFRONTAL BAND OF LIGHT RAIN HAS NOW
TRANSLATED EAST AND IS SET TO AFFECT MAINLY THE PIEDMONT. SW FLOW
STILL SUGGESTED BY POSITION OF TROUGH ON WV IMAGERY AND IS SEEN IN
LOWER LEVELS ON VAD WINDS FROM RADAR ACRS THE AREA. DPVA AHEAD OF
THE WAVE CONTINUES TO DRIVE LIGHT SHOWER ACTIVITY OVER THE ERN HALF
OF TENN AND NRN ALABAMA. THUS EVEN AREAS WEST OF THE MAIN RAIN BAND
STILL HAVE A GOOD CHANCE AT SEEING RAINFALL. LATEST RAP QPF SUGGESTS
THE BAND WILL GRADUALLY WEAKEN AS IT MOVES NE...BUT WITH SW FLOW
CONTINUING AND THE S/W STILL MOVING IN...PRECIP IS REINTRODUCED FROM
THE WEST.
AS OF 215 PM...A 500 MB POSITIVELY-TILTED SHORTWAVE TROF WILL
QUICKLY CROSS THE REGION TUESDAY MORNING...PUSHING A WEAK COLD FRONT
THRU THE AREA. A BAND OF GENERALLY LIGHT RAIN WILL WORK ACRS THE
CWFA FROM WEST TO EAST OVERNIGHT AHEAD OF THE FRONT...FORCED MAINLY
BY RIGHT FRONT QUADRANT UPR DIVERGENCE AND LLVL ISENT LIFT. THE
LIMITING FACTORS FOR BETTER RAIN RATES APPEAR TO BE WEAK MID LVL
LAPSE RATES AND MOISTURE TRANSPORT THAT WILL BE SIPHONED OFF BY
CONVECTION ALONG THE GULF COAST. GIVEN THE STRONG UPR SUPPORT...WILL
CARRY LIKELY TO CATEGORICAL POPS OVERNIGHT...WITH QPF IN THE TENTH
TO QUARTER INCH RANGE. SWLY FLOW UPSLOPE AREAS MAY SEE LOCALLY
HIGHER AMOUNTS. LLVL CAA WILL BEGIN TO RAMP UP AS PRECIP TAPERS OFF
EARLY TUESDAY MORNING. SO A BRIEF CHANGEOVER TO SNOW IS POSSIBLE
ABOVE 3500 FT...BUT LITTLE TO NO ACCUM IS EXPECTED. TEMPS WILL BE
ABOVE NORMAL OVERNIGHT WITH CLOUDS/PRECIP.
UPR JET AND SHORTWAVE WILL EXIT TO THE EAST BY MIDDAY
TUESDAY...ALLOWING FOR CLEARING SKIES AND END TO PRECIP. THICKNESSES
FALL LITTLE BEHIND THE FRONT...WITH DOWNSLOPE FLOW LIKELY CANCELING
OUT LLVL CAA. SO I BLENDED IN THE WARMER MET FOR MAX TEMPS.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
AS OF 2 PM MONDAY...THE SHORT TERM FCST PICKS UP AT 00Z ON WEDNESDAY
WITH DEEP UPPER TROFFING DIGGING DOWN OVER THE MISS RIVER VALLEY AND
STEEP UPPER RIDGING OVER THE FAR WESTERN CONUS. THE TROF AXIS WILL
LIKELY AMPLIFY AS IT APPROACHES THE CAROLINAS AND SHOULD MOVE OVER
THE CWFA BY EARLY THURS. AS THE AXIS LIFTS NE OF THE AREA ON THURSDAY
AFTERNOON...THE UPPER TROF IS REINFORCED AND DEEPENS AGAIN JUST TO
OUR WEST AS WE MOVE INTO FRIDAY.
ON WEDNESDAY...ANOTHER...STRONGER COLD FRONT WILL APPROACH THE CWFA
EARLY WED MORNING. A NARROW BAND OF MOISTURE ACCOMPANYING THIS SURGE
OF COLD AIR WILL BRING INCREASING PRECIP CHANCES ACROSS THE WESTERN
MTNS BY DAYBREAK...WITH FCST PARTIAL THICKNESSES AND FCST SOUNDINGS
CONTINUING TO SUGGEST AN ALL RAIN OR SNOW EVENT. THE SYNOPTIC
FORCING WILL SHIFT RAPIDLY TO THE EAST DURING THE MORNING...WITH A
TRANSITION TO A NW FLOW SNOW SCENARIO EXPECTED BY MID TO LATE
AFTERNOON. OVERALL SNOWFALL AMOUNTS HAVE DECREASED FOR THE NC/TENN
BORDER REGION COMPARED TO THE PREVIOUS FCST WITH MOST LOCATIONS
EXPECTED TO RECEIVE 1 TO 3 INCHES THRU THURS MORNING. TEMPS WILL
COOL MARKEDLY BEHIND THE FROPA WITH HIGHS REACHING THE MID TO UPPER
40S FOR THE LOWER ELEVATIONS AND LOW TO MID 30S FOR THE HIGHER
TERRAIN. WINDS WILL ALSO PICK UP QUITE A BIT WED AFTERNOON...HOWEVER
THEY SHOULD REMAIN BELOW ADVISORY CRITERIA.
ON THURSDAY...TEMPS WILL BE COLD LATE WED/EARLY THURS BUT HAVE BEEN
INCREASED A FEW DEGREES COMPARED TO THE PREVIOUS FCST. MINS IN THE
TEENS ARE EXPECTED OVER MUCH OF THE HIGHER TERRAIN...WHILE VALUES IN
THE MID TO LOW 20S ARE LIKELY ACROSS THE PIEDMONT AND FOOTHILLS. IN
THE WAKE OF THE FROPA...DRIER HIGH PRESSURE CENTERED OVER THE GULF OF MEX
WILL BRIEFLY SPREAD OVER THE REGION FROM THE WEST. SOME LINGERING NW
FLOW SNOW SHOWERS WILL BE THE MAIN CONCERN FOR THE CWFA...AND SHOULD
TAPER OFF BY 12Z OR SO. HIGH TEMPS WILL REMAIN 1 TO 2 CATEGORIES
BELOW CLIMO FOR MID JAN WITH LOWS OVERNIGHT WARMING AT LEAST A
CATEGORY AS THICKNESSES BEGIN TO REBOUND AS WE MOVE INTO FRI.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 220 PM EST MONDAY...THE EXTENDED RANGE STARTS WITH A HIGH
AMPLITUDE RIDGE OVER THE WEST COAST AND BRITISH COLUMBIA. WPC
COMMENTED THAT THEY FAVOR SLOWER AND HIGHER AMPLITUDE DOWNSTREAM
TROUGHING WITH THIS PATTERN...THOUGH FOR THE MOST PART THEY
APPEAR TO HAVE GONE WITH A SERIES OF ENSEMBLE BLENDS FOR THE
EXTENDED RANGE. THE 12 UTC OPERATIONAL ECMWF IS NOW QUITE A BIT
SLOWER AND DEEPER THAN THE 12 UTC GFS WITH ENERGY DROPPING INTO THE
LONG WAVE FRIDAY AND FRIDAY NIGHT. AS A RESULT THE ECMWF BRINGS A
SHOT OF STRONG Q-VECTOR CONVERGENCE ACROSS THE FA...INDUCING SFC
CYCLOGENESIS OVER WRN NC FRIDAY EVENING. THIS IN TURN BRINGS PCPN
ACROSS MOST OF THE FA...ESPECIALLY THE NC ZONES. THE GFS IS SO MUCH
FARTHER EAST THAT MOST OF IT/S PCPN RESULTS FROM NW FLOW SNOW. I/M
NOT GOING TO JUMP ON THE NEW ECMWF SOLUTION JUST YET CONSIDERING HOW
MUCH DRIER THE GFS IS. HOWEVER...THE ECMWF QPF WOULD IMPLY THE
POTENTIAL FOR SEVERAL INCHES OF SNOW OVER PARTS OF THE NC
MOUNTAINS...WITH LIGHTER AMOUNTS TO THE EAST LATE FRIDAY. I/LL ADD A
TAG FOR MODERATE SNOW ACCUMULATIONS OVER THE NC MTNS TO THE HWO FOR
FRIDAY TO ACCOUNT FOR THIS.
FAIR AND COLD WEATHER WILL FOLLOW FOR SATURDAY AND SUNDAY...WITH
MODERATING TEMPERATURES AND CONTINUED DRY CONDITIONS NEXT MONDAY.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
AT KCLT...VFR EXPECTED TO CONTINUE UNTIL AFTER MIDNIGHT EVEN AS
PRE-FRONTAL BAND OF -RA MOVES IN FROM THE WEST. WITH THE LEADING -RA
FALLING OUT OF MIDLEVEL CLOUDS...CIGS TAKE TIME TO LOWER AS
SATURATED LAYER DEEPENS BELOW THE CLOUD DECK. THEY SHOULD LOWER TO
VFR BY 09Z. BY DAYBREAK...AS PRECIP BEGINS TO DIMINISH...CIG AND
VSBY LOWER FURTHER. FORMATION OF LIFR CIG NOT OUT OF THE QUESTION
RIGHT AROUND OR JUST AFTER DAYBREAK. SW WINDS WILL CONTINUE THRU
TOMORROW MORNING...WITH FRONT FINALLY PUSHING THRU MIDDAY...CLEARING
CIGS OUT AND BRINGING SOMEWHAT GUSTY NW WINDS.
ELSEWHERE...STEADY -RA OR -DZ WILL PUSH INTO THE FOOTHILLS AND
PIEDMONT THIS EVENING AHEAD OF COLD FRONT WHICH ARRIVES TOMORROW.
UPPER S/W TROF IS PRODUCING NUMEROUS -SHRA OVER TENN...AND THOUGH
THE RAIN SHIELD MENTIONED ABOVE WILL LARGELY GO EAST OF THE MTNS
-SHRA SHOULD EVENTUALLY FILL IN BEHIND IT. CIGS ARE NOT EXPECTED TO
BE RESTRICTIVE UNTIL WELL AFTER ONSET OF PRECIP...BUT IFR EVENTUALLY
EXPECTED AT ALL SITES BY EARLY TUE. THIS WILL LAST UNTIL AFTER
DAYBREAK WHEN THE FRONT TURNS WINDS NWLY AND...AIDED BY
DOWNSLOPING...SCOURS OUT THE LOW CIGS...LEAVING VFR FOR THE
AFTERNOON.
OUTLOOK...A SERIES OF SWIFTLY MOVING LOW PRESSURE SYSTEMS WILL BRING
UNSETTLED CONDITIONS TO THE REGION MOST OF THIS WEEK. THE FIRST LOW
MOVES PAST TO THE SOUTH MONDAY NIGHT...FOLLOWED BY A COLD FRONT
TUESDAY NIGHT. FLIGHT RESTRICTIONS ARE POSSIBLE LATE MONDAY THROUGH
TUESDAY AFTERNOON...AND THEN AGAIN EARLY WEDNESDAY OVER SOME OF THE
AREA WITH THE NEXT FRONT. YET ANOTHER FRONT MAY ONCE AGAIN BRING
PRECIP AND RESTRICTIONS TO THE MTNS FRIDAY.
CONFIDENCE TABLE...
02-08Z 08-14Z 14-20Z 20-02Z
KCLT HIGH 94% HIGH 82% MED 79% HIGH 100%
KGSP HIGH 94% HIGH 80% HIGH 87% HIGH 100%
KAVL HIGH 84% MED 67% HIGH 80% HIGH 100%
KHKY HIGH 90% MED 77% HIGH 81% HIGH 100%
KGMU HIGH 94% HIGH 84% HIGH 87% HIGH 100%
KAND HIGH 91% MED 79% HIGH 80% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JOH
NEAR TERM...ARK/WIMBERLEY
SHORT TERM...JPT
LONG TERM...MCAVOY
AVIATION...WIMBERLEY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
708 PM EST MON JAN 13 2014
.SYNOPSIS...
HIGH PRESSURE WILL MOVE OFF THE CAROLINA COAST TONIGHT AS A COLD
FRONT APPROACHES FROM THE MISSISSIPPI AND OHIO RIVER VALLEYS. THIS
COLD FRONT WILL CROSS THE REGION THROUGH TUESDAY MORNING AND MOVES
OFF THE EAST COAST LATE TUESDAY AS ANOTHER MORE SIGNIFICANT COLD
FRONT CROSSES TENNESSEE. EXPECT MAINLY MOUNTAIN SNOW SHOWERS TUESDAY
NIGHT THROUGH WEDNESDAY BEFORE DRY HIGH PRESSURE RETURNS ON THURSDAY.
&&
.NEAR TERM /THROUGH TUESDAY/...
630 PM UPDATE...AS UPPER TROUGH CONTINUES TO SWING INTO THE LOWER
MISSISSIPPI VALLEY...THE PREFRONTAL BAND OF LIGHT RAIN HAS NOW
TRANSLATED EAST AND IS SET TO AFFECT MAINLY THE PIEDMONT. SW FLOW
STILL SUGGESTED BY POSITION OF TROUGH ON WV IMAGERY AND IS SEEN IN
LOWER LEVELS ON VAD WINDS FROM RADAR ACRS THE AREA. DPVA AHEAD OF
THE WAVE CONTINUES TO DRIVE LIGHT SHOWER ACTIVITY OVER THE ERN HALF
OF TENN AND NRN ALABAMA. THUS EVEN AREAS WEST OF THE MAIN RAIN BAND
STILL HAVE A GOOD CHANCE AT SEEING RAINFALL. LATEST RAP QPF SUGGESTS
THE BAND WILL GRADUALLY WEAKEN AS IT MOVES NE...BUT WITH SW FLOW
CONTINUING AND THE S/W STILL MOVING IN...PRECIP IS REINTRODUCED FROM
THE WEST.
AS OF 215 PM...A 500 MB POSITIVELY-TILTED SHORTWAVE TROF WILL
QUICKLY CROSS THE REGION TUESDAY MORNING...PUSHING A WEAK COLD FRONT
THRU THE AREA. A BAND OF GENERALLY LIGHT RAIN WILL WORK ACRS THE
CWFA FROM WEST TO EAST OVERNIGHT AHEAD OF THE FRONT...FORCED MAINLY
BY RIGHT FRONT QUADRANT UPR DIVERGENCE AND LLVL ISENT LIFT. THE
LIMITING FACTORS FOR BETTER RAIN RATES APPEAR TO BE WEAK MID LVL
LAPSE RATES AND MOISTURE TRANSPORT THAT WILL BE SIPHONED OFF BY
CONVECTION ALONG THE GULF COAST. GIVEN THE STRONG UPR SUPPORT...WILL
CARRY LIKELY TO CATEGORICAL POPS OVERNIGHT...WITH QPF IN THE TENTH
TO QUARTER INCH RANGE. SWLY FLOW UPSLOPE AREAS MAY SEE LOCALLY
HIGHER AMOUNTS. LLVL CAA WILL BEGIN TO RAMP UP AS PRECIP TAPERS OFF
EARLY TUESDAY MORNING. SO A BRIEF CHANGEOVER TO SNOW IS POSSIBLE
ABOVE 3500 FT...BUT LITTLE TO NO ACCUM IS EXPECTED. TEMPS WILL BE
ABOVE NORMAL OVERNIGHT WITH CLOUDS/PRECIP.
UPR JET AND SHORTWAVE WILL EXIT TO THE EAST BY MIDDAY
TUESDAY...ALLOWING FOR CLEARING SKIES AND END TO PRECIP. THICKNESSES
FALL LITTLE BEHIND THE FRONT...WITH DOWNSLOPE FLOW LIKELY CANCELING
OUT LLVL CAA. SO I BLENDED IN THE WARMER MET FOR MAX TEMPS.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
AS OF 2 PM MONDAY...THE SHORT TERM FCST PICKS UP AT 00Z ON WEDNESDAY
WITH DEEP UPPER TROFFING DIGGING DOWN OVER THE MISS RIVER VALLEY AND
STEEP UPPER RIDGING OVER THE FAR WESTERN CONUS. THE TROF AXIS WILL
LIKELY AMPLIFY AS IT APPROACHES THE CAROLINAS AND SHOULD MOVE OVER
THE CWFA BY EARLY THURS. AS THE AXIS LIFTS NE OF THE AREA ON THURSDAY
AFTERNOON...THE UPPER TROF IS REINFORCED AND DEEPENS AGAIN JUST TO
OUR WEST AS WE MOVE INTO FRIDAY.
ON WEDNESDAY...ANOTHER...STRONGER COLD FRONT WILL APPROACH THE CWFA
EARLY WED MORNING. A NARROW BAND OF MOISTURE ACCOMPANYING THIS SURGE
OF COLD AIR WILL BRING INCREASING PRECIP CHANCES ACROSS THE WESTERN
MTNS BY DAYBREAK...WITH FCST PARTIAL THICKNESSES AND FCST SOUNDINGS
CONTINUING TO SUGGEST AN ALL RAIN OR SNOW EVENT. THE SYNOPTIC
FORCING WILL SHIFT RAPIDLY TO THE EAST DURING THE MORNING...WITH A
TRANSITION TO A NW FLOW SNOW SCENARIO EXPECTED BY MID TO LATE
AFTERNOON. OVERALL SNOWFALL AMOUNTS HAVE DECREASED FOR THE NC/TENN
BORDER REGION COMPARED TO THE PREVIOUS FCST WITH MOST LOCATIONS
EXPECTED TO RECEIVE 1 TO 3 INCHES THRU THURS MORNING. TEMPS WILL
COOL MARKEDLY BEHIND THE FROPA WITH HIGHS REACHING THE MID TO UPPER
40S FOR THE LOWER ELEVATIONS AND LOW TO MID 30S FOR THE HIGHER
TERRAIN. WINDS WILL ALSO PICK UP QUITE A BIT WED AFTERNOON...HOWEVER
THEY SHOULD REMAIN BELOW ADVISORY CRITERIA.
ON THURSDAY...TEMPS WILL BE COLD LATE WED/EARLY THURS BUT HAVE BEEN
INCREASED A FEW DEGREES COMPARED TO THE PREVIOUS FCST. MINS IN THE
TEENS ARE EXPECTED OVER MUCH OF THE HIGHER TERRAIN...WHILE VALUES IN
THE MID TO LOW 20S ARE LIKELY ACROSS THE PIEDMONT AND FOOTHILLS. IN
THE WAKE OF THE FROPA...DRIER HIGH PRESSURE CENTERED OVER THE GULF OF MEX
WILL BRIEFLY SPREAD OVER THE REGION FROM THE WEST. SOME LINGERING NW
FLOW SNOW SHOWERS WILL BE THE MAIN CONCERN FOR THE CWFA...AND SHOULD
TAPER OFF BY 12Z OR SO. HIGH TEMPS WILL REMAIN 1 TO 2 CATEGORIES
BELOW CLIMO FOR MID JAN WITH LOWS OVERNIGHT WARMING AT LEAST A
CATEGORY AS THICKNESSES BEGIN TO REBOUND AS WE MOVE INTO FRI.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 220 PM EST MONDAY...THE EXTENDED RANGE STARTS WITH A HIGH
AMPLITUDE RIDGE OVER THE WEST COAST AND BRITISH COLUMBIA. WPC
COMMENTED THAT THEY FAVOR SLOWER AND HIGHER AMPLITUDE DOWNSTREAM
TROUGHING WITH THIS PATTERN...THOUGH FOR THE MOST PART THEY
APPEAR TO HAVE GONE WITH A SERIES OF ENSEMBLE BLENDS FOR THE
EXTENDED RANGE. THE 12 UTC OPERATIONAL ECMWF IS NOW QUITE A BIT
SLOWER AND DEEPER THAN THE 12 UTC GFS WITH ENERGY DROPPING INTO THE
LONG WAVE FRIDAY AND FRIDAY NIGHT. AS A RESULT THE ECMWF BRINGS A
SHOT OF STRONG Q-VECTOR CONVERGENCE ACROSS THE FA...INDUCING SFC
CYCLOGENESIS OVER WRN NC FRIDAY EVENING. THIS IN TURN BRINGS PCPN
ACROSS MOST OF THE FA...ESPECIALLY THE NC ZONES. THE GFS IS SO MUCH
FARTHER EAST THAT MOST OF IT/S PCPN RESULTS FROM NW FLOW SNOW. I/M
NOT GOING TO JUMP ON THE NEW ECMWF SOLUTION JUST YET CONSIDERING HOW
MUCH DRIER THE GFS IS. HOWEVER...THE ECMWF QPF WOULD IMPLY THE
POTENTIAL FOR SEVERAL INCHES OF SNOW OVER PARTS OF THE NC
MOUNTAINS...WITH LIGHTER AMOUNTS TO THE EAST LATE FRIDAY. I/LL ADD A
TAG FOR MODERATE SNOW ACCUMULATIONS OVER THE NC MTNS TO THE HWO FOR
FRIDAY TO ACCOUNT FOR THIS.
FAIR AND COLD WEATHER WILL FOLLOW FOR SATURDAY AND SUNDAY...WITH
MODERATING TEMPERATURES AND CONTINUED DRY CONDITIONS NEXT MONDAY.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
AT KCLT...VFR EXPECTED TO CONTINUE UNTIL AFTER MIDNIGHT EVEN AS
PRE-FRONTAL BAND OF -RA MOVES IN FROM THE WEST. WITH THE LEADING -RA
FALLING OUT OF MIDLEVEL CLOUDS...CIGS TAKE TIME TO LOWER AS
SATURATED LAYER DEEPENS BELOW THE CLOUD DECK. THEY SHOULD LOWER TO
VFR BY 09Z. BY DAYBREAK...AS PRECIP BEGINS TO DIMINISH...CIG AND
VSBY LOWER FURTHER. FORMATION OF LIFR CIG NOT OUT OF THE QUESTION
RIGHT AROUND OR JUST AFTER DAYBREAK. SW WINDS WILL CONTINUE THRU
TOMORROW MORNING...WITH FRONT FINALLY PUSHING THRU MIDDAY...CLEARING
CIGS OUT AND BRINGING SOMEWHAT GUSTY NW WINDS.
ELSEWHERE...STEADY -RA OR -DZ WILL PUSH INTO THE FOOTHILLS AND
PIEDMONT THIS EVENING AHEAD OF COLD FRONT WHICH ARRIVES TOMORROW.
UPPER S/W TROF IS PRODUCING NUMEROUS -SHRA OVER TENN...AND THOUGH
THE RAIN SHIELD MENTIONED ABOVE WILL LARGELY GO EAST OF THE MTNS
-SHRA SHOULD EVENTUALLY FILL IN BEHIND IT. CIGS ARE NOT EXPECTED TO
BE RESTRICTIVE UNTIL WELL AFTER ONSET OF PRECIP...BUT IFR EVENTUALLY
EXPECTED AT ALL SITES BY EARLY TUE. THIS WILL LAST UNTIL AFTER
DAYBREAK WHEN THE FRONT TURNS WINDS NWLY AND...AIDED BY
DOWNSLOPING...SCOURS OUT THE LOW CIGS...LEAVING VFR FOR THE
AFTERNOON.
OUTLOOK...A SERIES OF SWIFTLY MOVING LOW PRESSURE SYSTEMS WILL BRING
UNSETTLED CONDITIONS TO THE REGION MOST OF THIS WEEK. THE FIRST LOW
MOVES PAST TO THE SOUTH MONDAY NIGHT...FOLLOWED BY A COLD FRONT
TUESDAY NIGHT. FLIGHT RESTRICTIONS ARE POSSIBLE LATE MONDAY THROUGH
TUESDAY AFTERNOON...AND THEN AGAIN EARLY WEDNESDAY OVER SOME OF THE
AREA WITH THE NEXT FRONT. YET ANOTHER FRONT MAY ONCE AGAIN BRING
PRECIP AND RESTRICTIONS TO THE MTNS FRIDAY.
CONFIDENCE TABLE...
00-06Z 06-12Z 12-18Z 18-24Z
KCLT HIGH 100% MED 74% MED 73% HIGH 100%
KGSP HIGH 100% HIGH 83% HIGH 81% HIGH 100%
KAVL HIGH 94% MED 67% MED 72% HIGH 100%
KHKY HIGH 100% MED 73% MED 70% HIGH 100%
KGMU HIGH 99% HIGH 86% MED 79% HIGH 100%
KAND HIGH 99% MED 79% MED 75% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JOH
NEAR TERM...ARK/WIMBERLEY
SHORT TERM...JPT
LONG TERM...MCAVOY
AVIATION...WIMBERLEY
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
710 PM CST MON JAN 13 2014
.UPDATE...
ISSUED AT 708 PM CST MON JAN 13 2014
SOME CHANGES TO TONIGHT/S FORECAST BASED UPON CURRENT RADAR TRENDS
AND RAP/HRRR DEPICTION. AS NOTED BELOW...THE LOW LEVEL
FRONTOGENESIS AND WARM ADVECTION HAS PRIMARILY SHIFTED INTO THE
MINNESOTA RIVER VALLEY. WITH THE 900 MB FRONTOGENESIS BETWEEN THE
BUFFALO RIDGE AND MINNESOTA RIVER...SOME LIGHTS NOW COULD STILL
DEVELOP THIS EVENING IN SOUTHWEST MINNESOTA BUT BETTER CHANCE
REMAINS TO THE NORTHEAST. INSTEAD...LOOKING AT THE MAIN FORCING
FOR PRECIPITATION TO BE ASSOCIATED WITH THE UPPER LEVEL WAVE
MOVING SOUTHEAST ACROSS SD INTO IOWA. EXPECT A BAND OF
PRECIPITATION...SOMEWHAT CONVECTIVE IN NATURE...TO CONTINUE TO
ORGANIZE OVER CENTRAL SD THROUGH 03Z AND THEN MOVE SOUTHEAST
ACROSS THE AREA BETWEEN 03Z AND 09Z. TO THE NORTH OF THE VORTICITY
MAXIMUM...AM EXPECTING THAT A DEFORMATION ZONE WITH LIGHT
PRECIPITATION WILL SET UP PRIMARILY ACROSS SOUTHWEST MINNESOTA.
PRECIPITATION RATES WILL BE LIGHT AND...EXCEPT IN SW MN WHERE
DURATION MAY BE FOR A FEW HOURS...THE SPEED OF THE SYSTEM WILL
KEEP AMOUNTS TO A FEW HUNDREDTHS OF AN INCH.
AS FOR PRECIPITATION TYPE...THAT IS A LITTLE MORE DIFFICULT.
CURRENTLY FORECASTING THE PTYPE WILL BE DRIVEN BY SURFACE
TEMPERATURES. IN OTHER WORDS WHERE TEMPERATURES ARE ABOVE FREEZING
IT WILL EITHER BE RAIN OR RAIN AND SNOW WHILE WHERE IT IS AT OR
BELOW FREEZING IT WILL BE ALL SNOW. WITH ALL MODELS SHOWING 925 MB
TEMPS ABOVE FREEZING MUCH OF THE NIGHT...EXPECT THAT AS
PRECIPITATION STARTS AND WINDS INCREASE OUT OF THE WEST...MOST
AREAS WILL BE AT OR ABOVE FREEZING AND MOST PRECIPITATION WILL BE RAIN.
AS THE NIGHT PROGRESSES AND COLD AIR MOVES SOUTH...TEMPERATURES
WILL FALL BELOW FREEZING AND CHANGE IT TO SNOW. FOR THE MISSOURI
RIVER VALLEY...THE COLD AIR WILL PROBABLY LAG FAR ENOUGH BEHIND
THE PRECIPITATION TO KEEP IT ALL RAIN. IN SW MN...PRECIPITATION
WILL BE MORE SNOW ALTHOUGH IT WILL LIKELY START AS A MIX.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 417 PM CST MON JAN 13 2014
CHALLENGING FORECAST THIS EVENING AS MODELS HAVING A PRETTY
DIFFICULT TIME DETERMINING PRECIPITATION THREAT TONIGHT. FOR NOW
WILL LEAN TOWARDS THE ECMWF AND GFS OUTPUT WHICH CORRELATES MORE TO
THE PREVIOUS FORECASTS. MAIN REASONS ARE THAT THE LOW LEVEL WARM
ADVECTION IS ALREADY NORTH OF THE CWA AND WILL LIKELY REMAIN SO...SO
THE CHANCES FOR PRECIPITATION THIS EVENING WEIGH HEAVILY UPON
GETTING ANYTHING TO DEVELOP AS A VORTICITY LOBE MOVES FROM THE
WESTERN DAKOTAS INTO CENTRAL SD THIS EVENING. NOT BANKING ON MUCH
FROM THIS...ALTHOUGH THE NAM AND RAP ARE PRETTY EXCITED ABOUT
PRECIPITATION PRODUCTION WITHIN THIS LOCATION. WITH LITTLE OR NO LOW
AND MID LEVEL THERMAL GRADIENT AND A FAIRLY DRY LOWER LAYER
PRECIPITATION PRODUCTION SHOULD BE PRETTY DIFFICULT TO COME BY. HAVE
BACKED OFF ON POPS WEST OF INTERSTATE 29 THIS AFTERNOON AND EVENING
AND LOWERED SNOWFALL AMOUNTS EVERYWHERE. THE LOW LEVEL THERMAL
GRADIENT IS FARTHER NORTH AND EAST THAN PREVIOUSLY EXPECTED WHICH
HAS ALLOWED THE WARM ADVECTIVE PRECIPITATION TO DEVELOP FARTHER
NORTHEAST....WHICH IS RIGHT ON THE 925MB FRONT AND ALREADY MOVING
INTO WESTERN MINNESOTA. SO...HAVE MOVED THE START TIME OF THE
ADVISORY TO 6Z WHICH CORRELATES MORE TO THE INCREASE IN NORTHWEST
WINDS WHICH IF WE HAVE ANY SNOW ON THE GROUND WOULD START TO BLOW
AROUND.
TEMPERATURES STEADY TO FALLING ON TUESDAY WITH VERY STRONG WINDS.
THE WIND ADVISORY FOR THE AREA LOOKS SOLID AND EXPECT GUSTS TO 45
TO 50 MPH AT TIMES...ESPECIALLY IN THE MORNING.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 417 PM CST MON JAN 13 2014
WINDS SHOULD BE ON THE QUICK DOWNTREND ON TUESDAY NIGHT WITH A
WEDGE OF CLEARING WORKING ACROSS THE AREA WITH THE HIGH PRESSURE
RIDGE AXIS MOVING ACROSS. WINDOW FOR TEMPS TO DROP FAIRLY COOL
WITH 925 HPA COLD PUSH -12 TO -16C IN THE EASTERN HALF. SOME LOWS
DOWN CLOSER TO ZERO NEAR AND ADVANCE OF RIDGE AXIS...BUT SOME
LINGERING GRADIENT IN THE FAR EAST MAY HAVE SOMETHING TO SAY ABOUT
THAT...ESPECIALLY IF SHORT TERM SNOWFALL CONTINUES TO LOOK
DISAPPOINTING IN TERMS OF AMOUNTS.
STRONG WAVE WILL START TO MOVE INTO AREAS NEAR THE NORTHERN
PLAINS/CANADIAN BORDER BY WEDNESDAY EVENING. GANGLY WARM FRONT
EXTENDING SOUTHWARD WILL TRUDGE EASTWARD ACROSS THE CWA...WITH
A CONSENSUS OF NEAR THE I29 CORRIDOR BY 00Z THU. AHEAD OF THE
FRONT WILL DEVELOP A STOUT SOUTH TO SOUTHWEST FLOW...WITH A
WESTERLY PUSH OF WARMER AIR TO THE WEST OF THE FRONT. NOW LOOKING
LIKE THERE WILL BE ENOUGH NET LIFT WITHIN THE WARM FRONTAL ZONE
TO WARRANT A CHANCE LEVEL MENTION FOR LIGHT SNOW EVOLVING AS
BOUNDARY WORKS EASTWARD ACROSS THE CWA...MAINLY ACROSS THE NORTH
WHERE SOME BETTER SUPPORT TO DEEPER DIV Q. SHOULD BE A FAIR AMOUNT
OF CLOUDS EARLY ON...BUT SOME CLEARING WORKING IN FROM THE WEST
LATER IN THE DAY...OR AT A MINIMUM A THINNING TO HIGHER LEVEL
CLOUDS. ONE SHORTCOMING THAT LOOKED TO BE A FACTOR IN THE MODELS
WAS ALLOWING TEMPS TO WARM ENOUGH IN THE WARM SECTOR...AND RAISED
TEMPS OVER GUIDANCE ONCE AGAIN IN THE WEST...BACK CLOSER TO WHERE
PREVIOUS FORECAST RESIDED.
STILL LOOKING TO THE WIND THREAT THURSDAY AS THE MOST SIGNIFICANT
ISSUE IN THE FORECAST PERIOD. SOMEWHAT LOW CONFIDENCE IN TIMING OF
THE ABSOLUTE STRONGEST WINDS TIED TO WHEN LARGEST LOW LEVEL
ISENTROPIC SUPPORT FOR SUBSIDENCE WILL INITIATE...WITH UP TO 12H
DIFFERENCE BRACKETING SOLUTIONS OF NAM /SLOWEST/ TO GFS /FASTEST/.
AT THIS POINT...MAY SEE A LITTLE PARTIAL DECOUPLING IN THE WARM
SECTOR OVERNIGHT WHEN LIKELY TO GET SOME CONTINUED RISING TEMPS IN
THE EAST FOR A WHILE INTO THE NIGHT. MAY LIMIT SPEED POTENTIAL A
BIT...ESPECIALLY AT LOWER ELEVATIONS...BUT WILL NOT TAKE LONG TO
GET COUPLING TO KICK IN THOUGH WITH COLD AIR ADVECTION STARTING
AFTER 06Z. THIS SHOULD ALSO HELP TO KEEP TEMPS UP ABOVE GUIDANCE
WITH MIXING OF +2 TO -2 925 HPA TEMPS EXPECTED THROUGH 12Z. WITH
45 TO 55 KNOTS IN THE MID TO UPPER MIXED LAYER...WOULD PUT
PROSPECT OF NEEDING A HIGH WIND WATCH TO BE QUITE HIGH. FOR
NOW...WILL WORK THROUGH CURRENT WIND HIGHLIGHTS FIRST BEFORE
COMPLICATING MATTERS WITH THE NEXT...BUT CONTINUE TO HIT MENTION
HARD IN WEATHER STORY/HWO/SOCIAL MEDIA.
HAVE PUSHED MENTION TO LIGHT SNOW UP TOWARD LOWER LIKELY POPS IN
THE NORTHEAST HALF OF THE AREA AND TRIED TO TIME WITH AN EC/18Z
GFS CONSENSUS...WHICH HAS BEEN TREND IN MAJORITY SOLUTIONS TODAY.
WILL HAVE TO WATCH VISIBILITY ISSUES AS WELL...AS WILL BE QUITE
LOW AT TIMES OF ANY FALLING SNOW...BUT NOT SURE THERE WILL BE
ENOUGH SNOW FROM EARLIER TO MAKE WIDESPREAD BLOWING SNOW A LARGE
ENOUGH THREAT. DID CONTINUE MENTION OF SOME PATCHY OF BLOWING
SNOW. OTHER CONCERN WILL BE TEMPS STARTING TO FALL DURING THE
DAY... WHICH BY EVENING WITH THE STRONG WINDS WILL PRODUCE SOME
-20 TO -25 WIND CHILLS IN AT LEAST THE NORTHEASTERN HALF OF THE
AREA. COLD AIR DIGS INTO THE EASTERN AREAS ON FRIDAY...AND WILL GO
WITH HIGHS IN THE TEENS EAST TO LOWER 30S WEST AS ANOTHER RIDGE
AXIS DRIFTS ACROSS THE AREA.
LITTLE TO HANG ONES HAT ON AS FAR AS TIMING OR LOCATION OF
FEATURES IN THE SATURDAY TO MONDAY TIME FRAME. SHOULD TO CONTINUE
TO SEE A CLIPPERY NORTHWEST FLOW...BUT WITH RIDGE AXIS NUDGING
EAST...THE SIGNIFICANT PRECIPITATION THROUGH SHOULD REMAIN
NORTHEAST OF THE AREA...AND WILL BE LEFT TO A CHASE OF THE
POTENTIAL NON DIURNAL TEMPERATURE TRENDS. ONE PERIOD TO WATCH FOR
POSSIBLE LIGHT PRECIPITATION WOULD BE LATER FRIDAY NIGHT AND
SATURDAY... AND WITH STRONGER WARM AIR ADVECTION IN TYPES OF
SYSTEM... WOULD OPEN THE DOOR FOR SOME MIXED TYPE PRECIPITATION IF
SUCH A SOLUTION WOULD EVOLVE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 708 PM CST MON JAN 13 2014
MAIN FORECAST ISSUE IS WIND AND THE PROBABILITY OF LOW CLOUDS AND
PRECIPITATION WHICH COULD CREATE MVFR OR EVEN IFR CONDITIONS. THE
MOST CERTAIN ASPECT OF FORECAST IS THAT WINDS WILL COME UP TONIGHT
AFTER THE FRONT MOVES THROUGH. EXPECT WINDS TO BE GUSTING TO 30
KTS BY 12Z AND LIKELY TO 35 OR 40 KTS BY MID MORNING. THESE WINDS
WILL ONLY DECREASE IN THE LATE AFTERNOON.
AS FOR CLOUDS AND PCPN...THAT IS MUCH LESS CERTAIN. AS NOTED
ABOVE...THERE LOOKS TO BE A BAND OF PRECIPITATION THAT WILL ACROSS
THE AREA. BUT THE TIMING IS A BIT UNCERTAIN AND AT THIS POINT...AM
NOT EXPECTING A SOLID AREA OF PRECIPITATION. PLUS...ESP FOR KFSD
AND KSUX...PCPN MAY BE RAIN WHICH MEANS ITS IMPACT ON VSBYS WILL
BE MUCH LESS. FINALLY WITH DRY AIR NEAR THE SURFACE...CLOUD BASES
WILL HAVE DIFFICULTY FALLING BELOW 3000 FT. FOR THIS REASON...HAVE
NOT INCLUDED ANY PCPN IN TAFS AT THIS TIME BUT WILL MONITOR RADAR
TRENDS AND IF PCPN HAS GREATER COVERAGE WILL AMEND THE FORECAST.
ALSO WITH THE DRY AIR ONLY HAVE A FEW HOURS OF MVFR CONDITIONS AT
KHON AND KFSD TONIGHT.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY FROM MIDNIGHT TONIGHT TO 5 PM CST TUESDAY FOR
SDZ038-039-050-052>071.
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 3 PM CST
TUESDAY FOR SDZ040.
MN...WIND ADVISORY FROM MIDNIGHT TONIGHT TO 5 PM CST TUESDAY FOR
MNZ098.
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 3 PM CST
TUESDAY FOR MNZ071-072-080-081-089-090-097.
IA...WIND ADVISORY FROM MIDNIGHT TONIGHT TO 5 PM CST TUESDAY FOR
IAZ001>003-012>014-020>022-031-032.
NE...WIND ADVISORY FROM MIDNIGHT TONIGHT TO 5 PM CST TUESDAY FOR
NEZ013-014.
&&
$$
UPDATE...SCHUMACHER
SHORT TERM...08
LONG TERM...CHAPMAN
AVIATION...SCHUMACHER
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
604 PM CST MON JAN 13 2014
.UPDATE...
MADE A FEW CHANGES TO THE FORECAST EARLY THIS EVENING. HAVE
SHIFTED MORE TOWARDS THE LATEST HRRR MODEL RUNS IN DEPICTING POPS
AND WX. THUS ALSO HAD TO BACK OFF SOME ON TIMING OF WINTER WEATHER
ADVISORY. IT NOW BEGINS AT 3Z VS 00Z. THIS SHOULD WORK OKAY GIVEN
DELAYED PCPN.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT
LOW CONFIDENCE FORECAST TONIGHT REGARDING POTENTIAL FOR SNOW
AND/OR MIXED PRECIP. THE MODELS ARE SHOWING A VERY CONVECTIVE
PROFILE...AND AS IS TYPICAL WITH CONVECTION...ARE HAVING TROUBLE
DEDUCING EXACTLY WHERE AND WHEN THIS BANDED PRECIP WILL OCCUR. FOR
NOW HAVE NOT ALTERED STARTING TIMES FOR THE ADVISORIES CURRENTLY
IN PLACE. HOWEVER WOULD NOT BE SURPRISED IF WINDS AND SNOW ARE
LATE TO START...PERHAPS CLOSER TO 3Z RATHER THAN 0Z.
THE MAIN AREA OF PRECIP WILL BE ASSOCIATED WITH A SHORTWAVE AND
THE ENTRANCE REGION OF A LLJ WHICH ENTERS NORTH CENTRAL SD AROUND
0Z. THIS FEATURE THEN PROGRESSES SOUTHEAST THROUGH THE REMAINDER
OF THE NIGHT. WINDS WILL BECOME VERY GUSTY...ENHANCED BY SOME
SLIGHT SUBSIDENCE AND CAA BEHIND THE SYSTEM. MOST OF THE PRECIP
WILL FALL AS RAIN WEST OF THE JAMES VALLEY WITH SNOW EAST OF THE
JAMES. TEMPS AT ABERDEEN THIS AFTERNOON ARE HOVERING AROUND 30
DEGREES. MAX TEMPS ABOVE FREEZING WILL BE REACHED THIS EVENING
BEFORE FALLING AGAIN. SOME SLEET MAY MIX IN BRIEFLY AS PRECIP
EITHER COMES TO AN END IN THE WEST OR CHANGES TO ALL SNOW IN THE
EAST.
CURRENTLY RADAR SHOWS A BROAD AREA OF RAIN AND SNOW ACROSS FAR
WESTERN SD. THIS PRECIP BAND IS EXPECTED TO MOVE SOUTH AND
EAST...POSSIBLY CLIPPING STANLEY AND JONES COUNTIES. KEPT IN SOME
SLIGHT CHANCE POPS FOR SOUTH CENTRAL THIS EVENING.
WINDS WILL REMAIN ELEVATED THROUGH TUESDAY MORNING SO HAVE
BLOWING SNOW MENTIONED ACROSS THE EAST UNTIL NOON. THEN THE NEXT
SYSTEM APPROACHES ON WEDNESDAY. AHEAD OF THE COLD FRONT TEMPS WILL
POP INTO THE 30S AND 40S. MOST OF THE PRECIP WILL BE CONFINED TO
THE EAST...BUT COULD BE A WINTRY MIX AS THE COLD AIR PUSHES IN
LATE WED EVENING. WINDS ARE ALSO EXPECTED TO BE STRONG WED NIGHT
AND INTO THURSDAY.
.LONG TERM...THURSDAY THROUGH MONDAY
A POTENTIAL HEADLINE FOR THURSDAY/THURSDAY NIGHT IS THE MAIN
FORECAST CHALLENGE IN THE LONG TERM.
THE PERIOD BEGINS WITH A STRONG LOW PRESSURE SYSTEM OVER NORTHERN
MINNESOTA...WITH CAA PLUNGING SOUTHWARD ACROSS THE DAKOTAS. MOST
MODELS SHOW THE COLD FRONTAL BOUNDARY ENTERING THIS CWA BY 18Z
WITH CAA THROUGH THE AFTERNOON. THE GFS IS THE FASTEST WITH THE
FRONTAL PUSH AND WAS THEREFORE REJECTED. VERY STRONG NORTHERLY
WINDS ARE ANTICIPATED WITH THE CAA WITH 6 HOUR SURFACE PRESSURE
RISES OF 12 MB OR GREATER. 925 MB WINDS AND HALF KM WINDS ALL
SUPPORT HIGH WIND WARNING CRITERIA OF SUSTAINED WINDS OF 40 MPH.
WITH HEADLINES ALREADY OUT FOR TONIGHTS WEATHER...WILL FORGO
ADDING ADDITIONAL HEADLINES. TO COMPLICATE MATTERS...BOTH THE
ECMWF/GEM ARE SHOWING LIGHT SNOW ALONG WITH THE GUSTY NORTHERLY
WINDS WHICH WILL CAUSE HAZARDOUS CONDITIONS. THANKFULLY WITH WARM
TEMPERATURES EXPECTED ON WEDNESDAY SHOULD LOCK IN THE SNOW PACK
WITH BLOWING SNOW ONLY EXPECTED FROM FALLING SNOW.
WARMER TEMPERATURES BEGIN TO INVADE THE REGION BEYOND THE STORM
SYSTEM ON THURSDAY...WITH SUNDAY BEING THE WARMEST DAY WITH HIGHS
IN THE LOWER 30S...TO THE MID 40S. THERE IS A HINT OF ANOTHER
CLIPPER SYSTEM ON FRIDAY NIGHT...BUT AS OF NOW THE ECMWF IS DRY
FOR THIS CWA.
&&
.AVIATION...
00Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
A FAST MOVING SYSTEM WILL MOVE SOUTHEAST OVER THE REGION THIS
EVENING AND LATE TNT. A MIX OF RAIN/PELLETS AND BRIEF FREEZING
RAIN WILL BE POSSIBLE AT KABR...WITH MAINLY SNOW AT KATY.
KPIR/KMBG SHOULD SEE MOSTLY SOME LIGHT RAIN THIS EVENING. OVERALL
VFR CONDITIONS ARE EXPECTED. HOWEVER WITH THAT BATCH OF
PCPN...COULD SEE SOME LOWERED VSBYS AND MVFR CIGS FOR AWHILE.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY UNTIL 6 AM CST /5 AM MST/ TUESDAY FOR BUFFALO-
CAMPBELL-CORSON-DEWEY-EDMUNDS-FAULK-HAND-HUGHES-HYDE-JONES-
LYMAN-MCPHERSON-POTTER-STANLEY-SULLY-WALWORTH.
WINTER WEATHER ADVISORY UNTIL NOON CST TUESDAY FOR BROWN-CLARK-
CODINGTON-DAY-DEUEL-GRANT-HAMLIN-MARSHALL-ROBERTS-SPINK.
MN...WINTER WEATHER ADVISORY UNTIL NOON CST TUESDAY FOR BIG STONE-
TRAVERSE.
&&
$$
UPDATE...TDK
SHORT TERM...WISE
LONG TERM...SD
AVIATION...TDK
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1232 AM EST SUN JAN 12 2014
.SYNOPSIS...
A COLD FRONT WILL PROGRESS ACROSS THE AREA THIS EVENING AND BE
WELL OFF THE ATLANTIC COAST BY SUNDAY MORNING. HIGH PRESSURE WILL
BUILD INTO THE REGION FOR THE REMAINDER OF THE WEEKEND. A WARM
FRONT WILL LIFT ACROSS THE AREA ON MONDAY...FOLLOWED BY A COLD
FRONT ON TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 920 PM EST SATURDAY...
A FEW OF THE SHOWERS ALONG AND AHEAD OF THE FRONT ARE GROWING TALL
ENOUGH TO BECOME THUNDERSTORMS AND PRODUCE SOME SMALL HAIL. HAVE
BEEN ACCOUNTING FOR THIS IN SPECIAL WEATHER STATEMENTS. THE LATEST
FORECAST UPDATE WILL INCLUDE THIS POTENTIAL AS WELL FOR THE NEXT
HOUR OR TWO. NO MAJOR ADDITIONAL ADJUSTMENTS AT THIS TIME. HAVE
ONLY TWEAKED HOURLY TEMPERATURES AND DEW POINTS TO REFLECT THE
LATEST OBSERVATIONS AND EXPECTED TRENDS INTO THE EARLY MORNING
HOURS.
AS OF 650 PM EST SATURDAY...
SHOWERS ALONG THE COLD FRONT ARE CONTINUING TO PROGRESS EASTWARD
THROUGH THE AREA. A LOOK AT THE LOCAL WRF AND HRRR MODELS ARE
CAPTURING THIS ACTIVITY...AND OFFER A SOLUTION THAT BRINGS AT
LEAST ISOLATED COVERAGE ACROSS THE ENTIRE REGION COINCIDENT TO THE
FRONT. HAVE UPDATED THE FORECAST TO REFLECT THIS. NO OTHER
SIGNIFICANT CHANGES HAVE BEEN MADE.
AS OF 525 PM EST SATURDAY...
INSTABILITY HAS DEVELOPED IN THE DRY SLOT IMMEDIATELY COINCIDENT
TO THE COLD FRONT. ENOUGH HEATING HAS ALLOWED FOR SOME SCATTERED
SHOWERS TO DEVELOP OVER WEST VIRGINIA THAT ARE PROGRESSING INTO
THE WESTERN PORTION OF THE FORECAST AREA. AM NOT ANTICIPATING THE
SHOWERS TO MAKE A LOT OF PROGRESS AND DISSIPATE AROUND SUNSET.
AS OF 315 PM EST SATURDAY...
A COLD FRONT WAS ABOUT TO ENTER THE WESTERN PORTIONS OF THE FORECAST
AREA. PRECIPITATION HEAD OF IT WAS BECOMING CONFINED TO PRIMARILY
THE EASTERN HALF OF THE REGION AND PROGRESSING EASTWARD VERY
QUICKLY. ANTICIPATE THAT THE BACK EDGE OF THE PRECIPITATION WILL
EXIT THE EASTERN PART OF THE FORECAST AREA BY 800 PM EST. BEHIND THE
COLD FRONT...WINDS WILL SHIFT NORTHWEST AND BECOME GUSTY THROUGH THE
OVERNIGHT HOURS...ESPECIALLY ACROSS THE MOUNTAINS. 850 MB WINDS ARE
PROGGED TO PEAK BETWEEN 45 AND 50 KTS WITH AN ORIENTATION THAT GIVES
GOOD CROSS-BARRIER FLOW. WE ARE EXPECTED WIND ADVISORY CRITERIA
GUSTS ACROSS THE HIGHER TERRAIN OF THE NORTHERN MOUNTAINS OF NORTH
CAROLINA...NORTH INTO GRAYSON COUNTY VIRGINIA. THE PRESSURE GRADIENT
AND SUBSEQUENT 850 WINDS ARE PROGGED TO DECREASE QUICKLY DURING THE
FORENOON SUNDAY...THUS THE 900 PM END TIME FOR THE ADVISORY. THESE
SAME NORTHWEST WINDS WILL BE WEAKER ACROSS THE PIEDMONT...AND HELP
TO ERODE THE CLOUD COVER THANKS TO THE GENERATED SUBSIDENCE.
THE NORTHWEST FLOW AND LINGERING LOW LEVEL MOISTURE WILL HELP TO
GENERATE SOME UPSLOPE PRECIPITATION ACROSS SOUTHEAST WEST VIRGINIA
SOUTH INTO THE NORTHERN MOUNTAINS OF NORTH CAROLINA. WHILE WE WILL
MENTION SOME SNOW SHOWERS WHERE TEMPERATURES FALL LOW
ENOUGH...CONFIDENCE IN SNOW OCCURRING IS NOT VERY HIGH. PLENTY OF
DRY AIR WILL WORK INTO THE AREA BETWEEN ROUGHLY THE -6 C TO -25 C
RANGE...SO THERE LIKELY WILL NOT BE ANY ICE CRYSTALS FOR DENTRITIC
GROWTH. WILL MENTION THE POTENTIAL FOR DRIZZLE OR FREEZING DRIZZLE
GIVEN THE LOCAL TEMPERATURE. HOWEVER...HIGH LEVEL CLOUD COVER ABOVE
THIS DRY LAYER MAY HELP TO PROVIDE FOR SOME SEEDER FEEDER SNOW
PRODUCTION...BUT THE POTENTIAL FOR THAT IS ALSO ON THE LOW SIDE.
HAVE GONE FAIRLY CLOSE TO GUIDANCE ADJUSTED FOR LOCAL BIASES FOR THE
OVERNIGHT LOWS. THIS OFFERS LOWS OF THE LOW TO MID 30S OVER THE
MOUNTAINS WITH MID TO UPPER 30S ACROSS THE PIEDMONT.
ON SUNDAY...THE NORTHWEST WINDS WILL CONTINUE THROUGH ABOUT MIDDAY
BEFORE THEY WEAKEN AND BACK SOUTHWEST AS AN UPPER RIDGE STARTS TO
DEVELOP OVER THE REGION. WE EXPECT PLENTY OF DRY AIR TO CONTINUE
ADVECTING INTO THE AREA...AND THE TREND FOR ERODING CLOUD COVER WILL
TAKE PLACE ACROSS THE MOUNTAINS. HAVE FAVORED A BLEND OF THE MAV AND
MET MOS NUMBERS ADJUSTED FOR LOCAL BIASES FOR THE HIGH TEMPERATURES.
THIS WILL PLACE MID TO UPPER 40S ACROSS MOST OF THE MOUNTAIN
COUNTIES AND LOW TO MID 50S ACROSS THE PIEDMONT.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
AS OF 300 PM EST SATURDAY...
WILL START SUNDAY EVENING WITH A WEAK UPPER LEVEL RIDGE CROSSING THE
APPALACHIANS...WHILE HIGH PRESSURE IN THE LOW LEVELS MOVES OFFSHORE
FROM THE SOUTHEASTERN STATES. SOUTHWESTERLY FLOW AROUND THE
DEPARTING HIGH WILL DRAW WARM GULF AIR INTO OUR REGION...PUSHING
MONDAY AFTERNOON HIGHS INTO THE MID TO UPPER 50S FOR MOST
LOCATIONS... SEVERAL DEGREES ABOVE SEASONAL NORMALS.
THE UPPER RIDGE WILL BE MAKING A QUICK EXIT MONDAY AFTERNOON...IN
FAVOR OF AN UPPER LEVEL TROUGH AND ASSOCIATED COOL FRONT APPROACHING
FROM THE UPPER MIDWEST. LATEST FORECAST MODELS INDICATE THE TROUGH
IS NOT AS SHARP OR NEGATIVELY TILTED AS INDICATED IN PREVIOUS MODEL
RUNS...AND AM NO LONGER CONTEMPLATING THE POSSIBILITY OF
THUNDERSTORMS ACROSS THE SOUTHSIDE MONDAY NIGHT. PRECIPITATION IS A
GOOD BET HOWEVER...AND TEMPERATURES WILL BE WARM ENOUGH THROUGH THE
NIGHT TO SUPPORT RAIN.
THE COOL FRONT WILL PUSH THROUGH THE REGION EARLY TUESDAY MORNING...
BRINGING TUESDAY AFTERNOON HIGHS CLOSER TO SEASONAL NORMALS. WILL
SEE BRIEF PERIOD OF MAINLY DRY WEATHER TUESDAY AFTERNOON...BEFORE
OUR NEXT UPPER LEVEL TROUGH AND ASSOCIATED COLD FRONT ARRIVE TUESDAY
NIGHT. THIS TROUGH WILL BE COLDER THAN THE PREVIOUS SYSTEM
AND...WHILE THERE WILL NOT BE A GREAT DEAL OF MOISTURE FOR IT TO
WORK WITH...IS EXPECTED TO CAUSE RAIN SHOWERS TO CHANGE OVER TO SNOW
IN THE MOUNTAINS DURING THE EARLY MORNING HOURS OF WEDNESDAY. ANY
SNOW ACCUMULATIONS ARE EXPECTED TO BE LIGHT...AND CONFINED TO MAINLY
THE HIGHER RIDGES IN SOUTHEAST WEST VIRGINIA.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 300 PM EST SATURDAY...
POLAR VORTEX/EASTERN U.S. TROUGHING WILL PREVAIL DURING THE MEDIUM
RANGE. NORTHWEST FLOW ALOFT WILL DOMINATE THROUGH THE MUCH OF THE
PERIOD...AS THE MAIN TROUGH AXIS GRADUALLY PIVOTS NORTHEAST OF THE
REGION. A COUPLE OF ALBERTA CLIPPERS WILL ROTATE EASTWARD THROUGH
THE MEAN TROUGH WITH LIMITED MOISTURE. IN GENERAL...EXPECT
SEASONABLY COOL TEMPERATURES THROUGH THE PERIOD. UPSLOPE CLOUDS AND
COLDER TEMPERATURES ARE ON TAP FOR THE MOUNTAINS...WHILE SUNSHINE
WILL RESULT IN WARMER READINGS FOR THE EAST. KEPT THE HIGHEST POPS
ON WEDNESDAY IN THE NORTHWEST AS A WAVE TRAVEL ACROSS REGION. STILL
LOOK LIKE MOST OF THE MOISTURE WILL RIDE NORTHEAST OF OUR AREA. THE
FRONT PUSHES OFF TO THE EAST AND A DRY HIGH PRESSURE BUILDS IN FROM
THE WEST BY THURSDAY. ANOTHER MOISTURE-STARVED SURFACE COLD FRONT
WITH ARRIVES AROUND FRIDAY...FOLLOWED BY HIGH PRESSURE ON SATURDAY.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 635 PM EST SATURDAY...
SKY COVER OVERNIGHT WILL TREND TO VFR EAST OF THE CREST OF THE
RIDGE THANKS TO GOOD DOWNSLOPING BEHIND FRONT. ACROSS THE
MOUNTAINS A MIX OF MVFR ALONG WESTERN SLOPES TO LOW-END VFR
CLOUDS ARE EXPECTED THROUGH 12Z/7A SUNDAY. SOME LIGHT SNOW OR
DRIZZLE OR FREEZING DRIZZLE IS POSSIBLE ACROSS SOUTHEAST WEST
VIRGINIA SOUTH INTO THE NORTHERN MOUNTAINS OF NORTH CAROLINA. ALL
AREAS ARE EXPECTED TO BE VFR BY LATE SUNDAY MORNING. GUSTY
NORTHWEST WINDS WILL PREVAIL ACROSS THE MOUNTAINS OVERNIGHT WITH
THE HIGHER PEAKS APPROACHING 40 TO 45 KTS. WINDS WILL DECREASE
THROUGH THE DAY SUNDAY...AND LOW LEVEL WINDS BACK AND AN UPPER
RIDGE STARTS TO BUILD OVER THE AREA.
EXTENDED AVIATION FORECAST...
THE NEXT LOW PRESSURE SYSTEM IS PROJECTED TO ARRIVE BY MONDAY
NIGHT INTO TUESDAY MORNING...WHICH WOULD BRING SOME MVFR
CONDITIONS AND RAIN SHOWERS IN THE PIEDMONT...WITH A FEW SNOW
SHOWERS POSSIBLE IN THE MOUNTAINS. THE LONG RANGE MODELS SHOW A
SMALL CLIPPER SYSTEM TRACKING OVER THE MID ATLANTIC BY TUESDAY
NIGHT INTO WEDNESDAY. SOME UNCERTAINTY STILL EXISTS WITH THIS
COMPACT FEATURE...BUT IT WILL BE WORTH WATCHING AS SOME
ACCUMULATING SNOW MAY OCCUR FOR BLF/LWB ON WEDNESDAY...AND EVEN
BCB/ROA MAY SEE A FEW SNOW SHOWERS. OTHERWISE...VFR CONDITIONS
SHOULD PREVAIL ACROSS THE PIEDMONT FOR MOST OF NEXT WEEK...WHILE
MVFR CONDITIONS MAY BE MORE LIKELY IN THE MOUNTAINS DURING
WEDNESDAY AND THURSDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WIND ADVISORY UNTIL 9 AM EST THIS MORNING FOR VAZ015.
NC...WIND ADVISORY UNTIL 9 AM EST THIS MORNING FOR NCZ001-018.
WV...NONE.
&&
$$
SYNOPSIS...DS
NEAR TERM...DS
SHORT TERM...NF
LONG TERM...KK
AVIATION...DS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
322 PM CST SUN JAN 12 2014
.SHORT TERM...(TONIGHT THROUGH MONDAY)
ISSUED AT 322 PM CST SUN JAN 12 2014
THE UPPER MISSISSIPPI RIVER VALLEY REGION WAS ENJOYING THE WARM
SECTOR OF A 983MB AREA OF LOW PRESSURE MOVING THROUGH WESTERN
ONTARIO. AT 3 PM...TEMPERATURES ACROSS THE AREA RANGED FROM THE
MIDDLE 30S ACROSS NORTH CENTRAL WISCONSIN...TO THE UPPER 30S AND
EVEN A FEW LOWER 40S ACROSS THE REST OF THE FORECAST AREA.
AS THE LOW CONTINUES TO MOVE THROUGH ONTARIO...IT WILL DRAG A COLD
FRONT SLOWLY SOUTHEASTWARD ACROSS THE AREA. RAP SHOWING SOME FAIRLY
STRONG 700-500MB FRONTOGENESIS AND RIGHT ENTRANCE REGION OF 300MB
JET MOVING ACROSS THE AREA THIS EVENING FOR A CHANCE OF RAIN. WITH
TEMPERATURES REMAINING IN THE MIDDLE 30S FOR THE MOST PART THROUGH
THE EVENING...THREAT OF ANY FREEZING RAIN LOOKS MINIMAL. THE
EXCEPTIONS WILL BE LOWER-LYING COLD POCKET AREAS WITH UNTREATED
ROADWAYS. THINK THE HIGHEST THREAT AREA FOR THIS HAPPENING WILL BE
IN THE CRANBERRY BOG AREAS OF CENTRAL WI WHERE IT TYPICALLY GETS
COLDER QUICKER. AS THE SURFACE COLD FRONT CONTINUES TO MOVE THROUGH
THE AREA AFTER MIDNIGHT...APPEARS THE CHANCE OF A RAIN/FREEZING
SHIFTS MAINLY SOUTHEAST OF A LINE FROM MAUSTON TO BOSCOBEL WI LINE.
KEEPING POPS IN THE CHANCE CATEGORY SINCE BUFKIT IS STILL SHOWING
SOME SATURATION ISSUES THROUGH THE COLUMN. WILL CONTINUE TO MONITOR
THIS SITUATION...BUT NOT THINKING ANY WINTER HEADLINES NEEDED AT
THIS TIME. OTHERWISE...LOOK FOR OVERNIGHT LOWS IN THE 25-30 DEGREE
RANGE BY 6AM.
COLD AIR ADVECTION WILL BE IN PLACE ACROSS THE AREA ON MONDAY ALONG
WITH CYCLONIC FLOW ALOFT. THINKING THIS WILL GIVE US A MIXED BAG OF
CLOUD COVER WITH STEEPER LAPSE RATE TYPE STRATOCUMULUS AND THEN
INCREASING MID CLOUD LATE IN THE AFTERNOON AHEAD LOW PRESSURE AND A
WARM FRONT MOVING INTO THE DAKOTAS/WESTERN MN. HIGHS MONDAY EXPECTED
TO CLIMB ONLY A COUPLE DEGREES FROM THE OVERNIGHT LOWS...TOPPING OFF
IN THE MIDDLE 20S TO THE LOWER 30S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 322 PM CST SUN JAN 12 2014
12.12Z MODELS VERY CONSISTENT IN BRINGING A VIGOROUS MID-LEVEL
TROUGH AND SURFACE LOW ACROSS THE AREA MONDAY NIGHT THROUGH TUESDAY.
MODELS PRETTY MUCH LOCKING ONTO A COMMON SOLUTION...BRINGING THE
HEAVIEST SNOW THROUGH THE I-90/94 CORRIDOR AREAS. THE NAM IS THE
HIGHEST WITH ITS SNOW AMOUNTS RANGING FROM 2-5 INCHES WHILE THE
ECMFW IS INDICATING 1-3 INCHES. THE GFS COMES IN AT 1-4 INCHES. SREF
IS RIGHT IN THE MIDDLE WITH 1-4 INCHES. ALSO LOOKS LIKE THERE WILL
BE THE POTENTIAL FOR SOME BLOWING SNOW ACROSS THE OPEN PORTIONS OF
NORTHEAST IA AND SOUTHEAST MN TUESDAY AFTERNOON AS GUSTY NORTHWEST
WINDS SPREAD IN BEHIND THE SURFACE LOW. DUE TO THE GIVEN SNOWFALL
AMOUNTS AND WIND/BLOWING SNOW ISSUES...A WINTER WEATHER ADVISORY
HEADLINE WILL EVENTUALLY BE NEEDED FOR THIS EVENT AND WILL LIKELY BE
HOISTED BY THE MIDSHIFT CREW TONIGHT. OTHERWISE...LOOK FOR
TEMPERATURES MONDAY NIGHT IN THE TEENS TO LOWER 20S...THEN CLIMBING
THROUGH THE 20S ON TUESDAY.
ANOTHER SHOT AT SOME SNOW WILL COME ALONG WEDNESDAY NIGHT AS LIFT
INCREASES AHEAD OF A WARM FRONT EXTENDING FROM A VIGOROUS LOW
PASSING ACROSS SOUTHERN CANADA. SNOW CHANCES WILL CONTINUE INTO
THURSDAY WITH COLDER/UNSTABLE CYCLONIC FLOW ENTERING THE REGION.
ANOTHER TROUGH WILL DROP INTO THE REGION THURSDAY NIGHT FOR A
CONTINUED CHANCE OF LIGHT SNOW MAINLY EAST OF THE MISSISSIPPI RIVER.
EXPECT LOWS WEDNESDAY NIGHT IN THE TEENS WITH HIGHS ON THURSDAY
WARMING INTO THE 25 TO 32 DEGREE RANGE. COLDER AIR FILTERING INTO
THE AREA THURSDAY NIGHT WILL PRODUCE LOWS IN THE SINGLE DIGITS ABOVE
AND BELOW ZERO.
FRIDAY THROUGH THE WEEKEND LOOKS QUIET WEATHER-WISE AS A MID/UPPER
RIDGE OF HIGH PRESSURE BUILDS IN FROM THE PLAINS. LOOK FOR HIGHS
STARTING OUT COLD IN THE 10-15 DEGREE RANGE FRIDAY...MODERATING INTO
THE 20S SATURDAY AND SUNDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1200 PM CST SUN JAN 12 2014
PASSAGE OF SHORT TERM UPPER RIDGE TODAY ACTUALLY WILL BRING IN
SOUTHWEST FLOW AHEAD OF APPROACHING SHORT WAVE TROUGHS. FAIRLY
DECENT LIFT IN WARM AIR ADVECTION ZONE MAY STILL TAKE AWHILE TO
SATURATE DRY LOWER LEVELS BUT SHORT TERM GUIDANCE STILL SUGGESTING
THIS COULD LEAD TO SOME LIGHT PRECIPITATION LATE TODAY. CONFIDENCE
IN THIS IS ONLY MARGINAL WITH CEILINGS EXPECTED TO REMAIN IN VFR
RANGE. PRESSURE GRADIENT SHOULD ALSO LOOSEN THIS AFTERNOON SO GUSTY
WINDS MAY HAVE ALREADY BEEN AT PEAK.
AS FIRST SHORT WAVE BRINGS COLD FRONT IN OVERNIGHT...COLD AIR
ADVECTION SCHEME SETS UP AND WITH NORTHWEST WINDS...COULD BRING IN
PERIOD OF MVFR TO PATCHY IFR CONDITIONS MONDAY MORNING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...SHEA
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
243 AM EST TUE JAN 14 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH THE FORECAST AREA EARLY TODAY. WEAK
HIGH PRESSURE BEHIND THE FRONT WILL BE OVER THE AREA THIS EVENING.
A REINFORCING COLD FRONT WILL MOVE THROUGH THE AREA WEDNESDAY
AFTERNOON. LITTLE MOISTURE WILL BE ASSOCIATED WITH THIS FRONT.
&&
.NEAR TERM /THROUGH TODAY/...
CONVERGENCE ALONG THE COLD FRONT PLUS LIFT ASSOCIATED WITH THE
RIGHT ENTRANCE REGION OF THE H25 JET WAS HELPING SUPPORT SHOWERS
THIS MORNING. RADAR TRENDS SHOW SHOWER COVERAGE HAS DIMINISHED BUT
THE SPC WRF AND HRRR SHOW COVERAGE INCREASING AGAIN LATER THIS
MORNING. THIS INCREASE APPEARS TO BE IN RESPONSE TO LIFT
ASSOCIATED WITH THE MAIN MID-LEVEL SHORTWAVE TROUGH AFFECTING THE
AREA. THE HIGH-RESOLUTION MODELS INDICATE SHOWERS ENDING FROM WEST
TO EAST FROM ABOUT 1100 AM TO 100 PM. DRYING BEHIND THE MID-
LEVEL SHORTWAVE TROUGH AND H85 COLD ADVECTION SHOULD BECOME
DOMINATE BEGINNING AROUND 100 PM ACCORDING TO THE NAM AND GFS. WE
WILL GET OFF TO A RELATIVELY WARM START BECAUSE OF CLOUDINESS AND
MIXING AHEAD OF THE COLD FRONT THIS MORNING. THE TEMPERATURE
GUIDANCE WITH HIGHS NEAR 60 NORTH TO MIDDLE 60S SOUTHEAST APPEARS
REASONABLE.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
WEAK RIDGING WILL BE OVER THE FORECAST AREA THIS EVENING WITH THE
RIDGE FURTHER WEAKENING LATE TONIGHT AND WEDNESDAY AHEAD OF THE
NEXT COLD FRONT. THIS REINFORCING FRONT WILL MOVE THROUGH THE AREA
WEDNESDAY AFTERNOON AND EVENING. THE MODELS CONTINUE TO INDICATE
MOST OF THE MOISTURE WITH THIS SYSTEM WILL REMAIN NORTH AND EAST
OF THE FORECAST AREA. THE NAM AND GFS MOS SUPPORT POPS LESS THAN
20 PERCENT IN THE SOUTH AND CENTRAL PART TO 20 TO 50 PERCENT IN
THE NORTH PART WEDNESDAY AFTERNOON AND EVENING. THE GFS SHOWS THE
LEAST MOISTURE COMPARED TO THE NAM AND ECMWF. PLAN TO FORECAST
SLIGHT CHANCE POPS IN THE NORTH PART AS INDICATED BY THE GFS MOS.
THE HIGHER NAM MOS HAS NOT BEEN CONSISTENT. THERE IS A POSSIBILITY
THERE WILL BE ENOUGH COOLING FOR SNOW IN THE NORTH PART BUT WITH
MARGINAL TEMPERATURES AND MOISTURE THE CHANCE APPEARS LOW AT THIS
TIME. THE NAM... GFS...AND ECMWF INDICATE DRYING AND DOWNSLOPE FLOW
BY LATE WEDNESDAY NIGHT. THE TEMPERATURE GUIDANCE WAS CONSISTENT.
EXPECT LOWS MAINLY IN THE MIDDLE 30S TONIGHT WITH HIGHS IN THE
MIDDLE 50S TO NEAR 60 WEDNESDAY. THE WARM GUIDANCE TEMPERATURES
WEDNESDAY APPEAR REASONABLE BECAUSE OF WARMING THAT WILL OCCUR
JUST AHEAD OF THE COLD FRONT. IT WILL TURN MUCH COOLER BY LATE
WEDNESDAY NIGHT BEHIND THE FRONT WITH LOWS IN THE MIDDLE 20S TO
AROUND 30.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
THE MEDIUM-RANGE MODELS CONTINUE TO DISPLAY BELOW NORMAL
TEMPERATURES WITH AN UPPER-LEVEL TROUGH REMAINING OVER THE
EASTERN PART OF THE NATION. THE GFS AND ECMWF SHOW A COLD FRONT
FRIDAY WITH LITTLE MOISTURE. THE 00Z ECMWF INDICATED LESS MOISTURE
THAN PREVIOUS RUNS AND WAS IN BETTER AGREEMENT WITH THE GFS. WE
MAINTAINED THE DRY FORECAST ALTHOUGH THERE IS INCREASED FORECAST
UNCERTAINTY BECAUSE OF THE LACK OF MODEL RUN-TO-RUN CONSISTENCY.
EXPECT TEMPERATURES WILL REMAIN BELOW NORMAL AS INDICATED BY THE
GFS...ECMWF AND EKD MOS.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
FIRST AREA OF LIGHT TO MODERATE RAIN...ASSOCIATED WITH LEADING UPPER
IMPULSE AND ISENTROPIC LIFT...HAS PUSHED INTO THE AREA...WITH THE
BACK EDGE HAVING CLEARED AGS/DNL. SECONDARY PATCHY LIGHT RAIN
SHOWERS ASSOCIATED WITH COLD FRONT AND MAIN UPPER TROUGH WILL MOVE
INTO THE FORECAST AREA LATER THIS MORNING. CIGS/VSBYS ARE EXPECTED
TO DROP DURING THE EARLY MORNING HOURS AS LOW LEVELS BECOME MORE
SATURATED. LATEST GUIDANCE BRINGS CIGS DOWN TO IFR...WITH MVFR
VSBYS...WITH MOST RESTRICTIONS IN THE 08Z-15Z TIME FRAME. AFTER
FRONTAL PASSAGE MID TO LATE MORNING TUE...EXPECT A RETURN TO VFR BY
LATE MORNING TO MIDDAY WITH RISING CIGS.
EXTENDED AVIATION OUTLOOK...A SERIES OF DRY COLD FRONTS WILL MOVE
THROUGH DURING THE WEEK. LOW CONFIDENCE ON ANY PRECIP OR
RESTRICTIONS...BUT BREEZY CONDITIONS POSSIBLE AT TIMES.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1139 PM CST MON JAN 13 2014
.UPDATE...
ISSUED AT 913 PM CST MON JAN 13 2014
JUST ISSUED A WINTER WEATHER ADVISORY ALONG AND NORTH OF HIGHWAY
30 FOR TUESDAY. THE ADVISORY IS FOR A COMBINATION OF STRONG
WINDS...SNOW AND BLOWING SNOW. THE 00Z NAM AS WELL AS THE LATEST
HRRR AND RUC13 STILL SUGGEST ACCUMULATING SNOW SPREADING OVER THE
AREA FROM EARLY TUESDAY MORNING THROUGH MID MORNING. THERE MAY BE
A MIX AT THE ONSET ESPECIALLY SOUTH OF I80 BUT TO THE NORTH IT
SHOULD BE BRIEF IF AT ALL. 18Z/00Z MODELS ARE SHOWING MID LEVEL
LAPSE RATES IN THE 7 TO 8 C/KM RANGE WHEN THE SNOW MOVES THROUGH
SUGGESTING A CONVECTIVE NATURE TO THE SNOW. THE LAST FEW RUNS OF
THE HRRR HAS BEEN SHOWING SOME STRONG REFLECTIVITIES OVER THE NORTH
THIRD BETWEEN 12Z AND 15Z. I/M NOT SURE IT WILL THUNDER...BUT IT
CERTAINLY LOOKS AT LEAST LIKE SOME BRIEF BUT HEAVY BURSTS OF SNOW
FOR SOME AREAS TOMORROW MORNING. KEPT AMOUNTS IN THE 1 TO 2 INCH
RANGE BUT ADDED THE LOCALLY HIGHER CAVEAT WITH THE POTENTIAL
CONVECTION. THE WIND SHOULD KICK WEST TO EAST MID TO LATE MORNING.
MENTIONED GUSTS UP TO 45 MPH BUT THIS COULD BE CONSERVATIVE. MODEL
SOUNDINGS ARE SHOWING A SHALLOW SURFACE BASED MIXED LAYER
DEVELOPING WITH THE ARRIVAL OF THE COLDER AIR. WIND GUSTS AT THE
TOP OF THE MIX LAYER ARE PROGGED TO BE 40 TO 45 KTS. IF MODELS
MAINTAIN THESE STRONG ELEVATED WINDS IN LATER RUNS THEN THIS COULD
LEAD TO A WIND ADVISORY BEING ISSUED LATER TONIGHT...SOUTH OF THE
CURRENT WINTER WX ADVISORY. GUSTY WINDS WILL CONTINUE INTO THE
EVENING BUT SHOULD DIMINISH ENOUGH TO END ANY SIGNIFICANT BLOWING
SNOW.
&&
.SYNOPSIS...
ISSUED AT 230 PM CST MON JAN 13 2014
A DYNAMIC AND CHALLENGING FORECAST THE NEXT 24 HOURS. ANALYSIS AND
VERIFICATION AT NOON INDICATE A FAST MOVING AND QUITE INTENSE
ALBERTA CLIPPER SYSTEM IS DIVING RAPIDLY SE AND IS NOW MOVING INTO
MONTANA AS OF 2 PM CST. PRESSURE RISE/FALL COUPLETS...WINDS AND
PRESSURE ALL INDICATE SYSTEM IS STRONGER AND DIGGING MORE THAN
MOST SOLUTIONS FROM 12Z. THIS SUPPORTS OCCLUSION AND PRECIPITATION
DEVELOPING TO EXPLODE BEFORE IT GETS TO FORECAST AREA. THE HIGH NON
LINEARITY OF THE IMBALANCES DUE TO ACCELERATIONS (NON-HYDROSTATIC)
AND MIXING (NON-ADIABATIC) SUGGEST LOTS OF CHANGEABLE WEATHER WITH
IMPACTS ON TRACKS OF SNOW AMOUNTS TONIGHT INTO TUESDAY...WIND AND
WIND GUSTS. LOCAL TOOLS AND TECHNIQUES ALL SUGGEST NORTHERN 1/2 OF
AREA THE BIGGEST AFFECTED WITH ISOLATED THUNDER POSSIBLE WITH LOBE
ON INTENSE BUT NARROW SNOW BAND PASSING TOWARD MORNING. UPSTREAM
ENERGY AND ANALYSIS INDICATE MORE CHANGEABLE WEATHER WITH A LARGER
AND STRONGER SYSTEM THURSDAY INTO FRIDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 230 PM CST MON JAN 13 2014
TONIGHT...ONE OF THE STRONGER ALBERTA CLIPPER TO AFFECT FORECAST
AREA LATE TONIGHT WELL INTO TUESDAY. WARM ADVECTION WING SNOW WITH
SOME SLEET AND RAIN FAR SE SECTIONS THAT WILL CHANGE TO SNOW DUE
TO EVAPORATIVE COOLING WILL BLOOM ACROSS MID PORTIONS OF IOWA
AROUND OR JUST BEFORE MIDNIGHT. THIS AREA WILL REACH NEAR THE MISSISSIPPI
RIVER VALLEY AROUND 6 AM WITH ISOLATED THUNDER POSSIBLE PER "LIFT"
TOOL ALONG AND NORTH OF I-80. EXPECT A 10-30 MILE WIDE BAND OF 30-40+
DBZ ECHOES WITH SNOWFALL RATES OF 1+ INCH AN HOUR THAT MAY LAST
ANYWHERE FROM 15 MINUTES TO OVER AN HOUR. MOST LOCATIONS WILL PICK
UP .75 TO NEAR 2 INCHES ALONG AND NORTH OF I-80 WITH HEAVIEST SNOWS
NORTH OF TRIPLE POINT ALONG AND NORTH OF HIGHWAY 30. THE SNOW WILL
DIMINISH TO FLURRIES OR LIGHT SNOW BY MID MORNING TUESDAY. SKIES
WILL BECOME OVERCAST BY MIDNIGHT WITH SOUTH WINDS INCREASING TO TO
20+ MPH OVERNIGHT. MINS 25 TO 32 DEGREES FROM NORTH TO SOUTH WITH
LOWS MAINLY BEFORE MIDNIGHT WITH RISING TEMPERATURES OVERNIGHT.
TUESDAY...MAIN ISSUE WILL BE STRONG AND VERY GUSTY WINDS. STRONG
COLD FRONT WITH SNOWS DIMINISHING TO FLURRIES BY MID/LATE MORNING
WITH NW WINDS ARRIVING FROM NW TO SE BETWEEN 6 AM AND 11 AM. LOCAL
TOOLS ALL INDICATE 25 TO 35+ MPH WITH SOME GUSTS AROUND 45 MPH
THAT WILL BE VERY CLOSE TO WIND ADVISORY CRITERIA WITH MINOR
BLOWING AND DRIFTING SNOW DUE TO ONLY 1 TO 2 INCHES OF NEW SNOW
EXPECTED. TEMPERATURES TO FALL SIGNIFICANTLY BEHIND THE FRONT INTO
THE LOW/MID TWENTIES TOWARD DUSK WITH UPPER TEENS POSSIBLE FAR NW
SECTIONS. LATER SHIFTS MAY NEED TO ISSUE WIND ADVISORY IF TRENDS
CONTINUE. A WINTER WEATHER ADVISORY MAY ALSO BE AN OPTION IF SNOWS
LINGER AND ARE A BIT HIGHER ON SNOW AMOUNTS. NICHOLS
.LONG TERM...(TUESDAY NIGHT THROUGH NEXT MONDAY)
ISSUED AT 230 PM CST MON JAN 13 2014
TUESDAY NIGHT AND WEDNESDAY...BRISK NORTHWEST WINDS OF 15 TO 25 MPH
TO CONTINUE INTO TUE EVENING...AND PROBABLY NOT DROPPING OFF TO
10-15 MPH TIL LATE IF BULK OF WRAP AROUND STRATUS MAINTAINS ACRS THE
AREA. MORE ORGANIZED LIGHT SNOW OR SHOWERS WILL BE EXITING OFF TO
THE EAST DURING THE EVENING...BUT DEEPENING CYCLONIC FLOW COULD
CONTINUE TO WRING OUT FLURRIES ACRS MUCH OF THE FCST AREA WELL INTO
THE NIGHT. LATEST MODEL RUNS CONTINUE TO VARY ON HOW COLD IT WILL
GET BY WED MORNING...AND IF CLOUDS AND BRISK MIXING WINDS LINGER
INTO WED MORNING THE MILDER OF THE LOW TEMP GUIDANCE MAY VERIFY
BETTER. BUT STRENGTH OF LLVL COLD AIR ADVECTION ALSO MUST BE TAKEN
INTO ACCOUNT AND FEEL A BLEND OF ALL SOLUTIONS MAY TAKE ALL OF THESE
VARIABLES INTO ACCOUNT. WIND CHILLS MAY STILL GET TO 10 BELOW IN THE
NORTHWESTERN CWA BY EARLY WED MORNING. A PASSING BOUT OF BOTH SFC
AND UPPER RIDGING TO MAKE FOR A FAIR WX DAY WED WITH LATE DAY RETURN
FLOW HELPING TEMPS RECOVER BACK INTO THE UPPER TEENS TO MID 20S BY
LATE AFTERNOON. THEN AN INTENSE ALBERTA TYPE CLIPPER LOW PRESSURE
SYSTEM STILL BEING SLATED BY THE MODELS TO RIDE ACRS NORTHWEST
PACIFIC RIDGE AND DUMP DOWN TOWARD THE WESTERN LK SUPERIOR BSN
THROUGH THU MORNING. WILL THROW OUT THE 12Z GFS WHICH KEEPS THE DVN
CWA DRY OVERNIGHT AND THE SOUTHEASTERN FLANKING WARM AIR ADVECTION
WING OF SNOW TO THE NORTH OF US...WHILE THE BULK OF THE OTHER
SOLUTIONS SWEEP SOME TYPE OF ELEVATED SNOW BAND ACRS PORTIONS OF THE
AREA INTO EARLY THU MORNING. WILL EXPAND THE CHC POPS SOUTHWARD.
SOME LIGHT SNOW ACCUMULATIONS MAY EVEN OCCUR ESPECIALLY NORTH OF I80
BY 12Z THU. AS FOR TEMPS...WITH STRENGTHENING SOUTHWESTERLY LLVL
FLOW ACRS THE AREA TO THE LEE OF THIS SYSTEM...LOW TEMPS MAY OCCUR
THE FIRST FEW HOURS OF THE EVENING AND THEN RISE OVERNIGHT INTO THU
MORNING. BUT EVAPO-COOLING FROM ANY PRECIP WING MAY MAKE FOR STEADY
TEMP PERIODS AS WELL.
THURSDAY AND FRIDAY...SUB 990 MB LOW CENTER WILL BE LOOKING TO DIG
DOWN ACRS THE NORTHWESTERN INTO CENTRAL GRT LKS THU. LATEST PLACEMENT
AND HANDLING ON 12Z MEDIUM RANGE SOLUTIONS GENERALLY SUGGEST THAT
AFTER WHAT EVEN WAA WING OF PRECIP THAT MANAGES TO MAKE IT ACRS THE
LOCAL ARE CLEARS OFF TO THE EAST THU MORNING...THE DVN CWA WILL
TEMPORARILY BE IN A DRY SLOT AND TYPE OF WARM SECTOR...BEFORE A VERY
STRONG IN-WRAPPING LLVL COLD CONVEYOR SURGES SOUTHEASTWARD ACRS ALL
OF IA BY AFTERNOON AND INTO THE EVENING. RATHER MILD HIGHS IN THE
30S MAY OCCUR THU MORNING...BEFORE TEMPS FALL OFF AGAIN. BUT THE
MAIN WX STORY STILL LOOKS LIKE WILL BE THE VERY STRONG WINDS SURGING
ACRS THE AREA LATER THU AFTERNOON AND LASTING WELL INTO THE OVERNIGHT
THU NIGHT. VERY TIGHT LLVL CYCLONIC PRESSURE GRADIENT...A PROBABLE
VERY LARGE PRESSURE RISE-FALL COUPLET TO ENHANCE ISALLOBARIC SURGE
COMPONENT TO THE WINDS...AND EARLY SIGNS OF A TROP-FOLD DOWN TO
UNDER 550 MB ROTATING ACRS THE REGION THU EVENING SHOULD MAKE FOR
HIGHER END WIND ADVISORY CRITERIA TO BE MET IN OR VERY CLOSE TO THE
CWA. EARLY INDICATIONS STILL POINT AT GUSTS OF 45 TO NEAR 50 MPH BY
THUR EVENING. THESE STRONG WINDS IN WRAP AROUND SNOW SHOWERS THU
EVENING AND INTO THE OVERNIGHT MAY MAKE FOR GREATLY REDUCED LOCALIZED
VSBYS. GENERAL ENSEMBLES AND GFS/ECMWF AGREEMENT ALSO POINT TO -20C
H85 MB COLD POOL TO GET ADVECTED DOWN ACRS THE AREA THU NIGHT INTO
FRI MORNING. DESPITE MIXING WINDS AND CLOUD COVER...STOUT LLVL COLD
AIR ADVECTION TO DRIVE TEMPS INTO THE LOWER SINGLE DIGITS ABOVE
ZERO...TO LOWER TEENS THROUGH FRI MORNING. WIND CHILL ADVISORY
CRITERIA MAY BE NEARED IN THE NORTHWESTERN THIRD OF THE CWA BY EARLY
FRI MORNING. INCOMING RIDGE GRADIENT TO CONTINUE TO MAKE FOR
BLUSTERY CONDITIONS ON FRI UNTIL WIND DECREASE BY LATE AFTERNOON AS
UPSTREAM RIDGE DRAWS CLOSER. THE NEW 12Z ECMWF EVEN SUGGESTS AT
SOME RENEWED DIURNAL SNOW SHOWER DEVELOPMENT FRI MORNING BEFORE THEY
DECAY AGAIN IN THE AFTERNOON. BRUNT OF LLVL COLD POOL PROGGED TO
SLIDE EAST OF THE AREA BY FRI AFTERNOON...BUT STILL SEE DAYTIME
HIGHS STRUGGLING TO RECOVER TO THE GUIDANCE SUGGESTED LOW TO MID
TEENS NORTH OF I80...UPPER TEENS SOUTH. RIDGE OVERHEAD...SFC WIND
DECOUPLE AND CLOUD CLEAR-OFF MAY MAKE FOR A SUBZERO NIGHT
IN PORTIONS OF THE DVN CWA. BUT THE 1Z GFS SHUTTLES A CLIPPER DOWN IN
FRESHLY HIGH AMPLIFIED NORTHERLY FLOW TO THE WEST OF DEEP EASTERN
CONUS TROF BASE. THUS THIS MODEL STARTS TO WARM AIR ADVECT
OVERNIGHT AS WELL AS PRODUCE 1-3+ INCHES OF SNOW IN THE NORTHEASTERN
THIRD OF THE DVN CWA BY SAT MORNING. BULK OF OTHER MEDIUM RANGE
SOLUTIONS ARE DRY AND COLD AND WILL SIDE THAT WAY FOR NOW. PROBABLY
NOT COLD ENOUGH FOR FRI NIGHT LOWS.
SATURDAY THROUGH NEXT MONDAY...MODEL RUN VARIANCES BETWEEN SOLUTIONS
AND THE PREVIOUS RUNS OF THEMSELVES CONTINUE FOR NEXT WEEKEND. BUT
AGAIN...ASSESSING THE GENERAL TRENDS AND BEHAVIOR OF UPPER JET
DYNAMICS SUGGEST A TEMPORARY FLATTENING OUT OF THE MEAN FLOW PATTERN
ACRS MUCH OF THE CENTRAL INTO EASTERN CONUS AND EVENTUAL TEMP
MODERATION BACK INTO THE 30S OF SUNDAY INTO MONDAY. NOT MUCH IN THE
WAY OF ORGANIZED PRECIP MAKERS EVIDENT AT THIS POINT AS WELL DURING
THIS PERIOD. BUT TRENDS IN THE OSCILLATIONS AND SOME INFLUENCE OFF
THE NORTH PACIFIC...POINT TO THE COLD CORE L/W TROF SNAPPING BACK
INTO PLACE ACRS THE CENTRAL INTO EASTERN CONUS BY MID NEXT WEEK.
BOTH THE 12Z RUN GFS AND ECMWF SEEM TO BE PICKING UP ON THIS IDEA
WITH ANOTHER SIGNIFICANT ARCTIC SURGE FLOWING DOWN ALONG AND EAST OF
THE MS RVR VALLEY NEXT TUE NIGHT INTO WED...WHILE THE POLAR VORTEX
TRIES TO MIGRATE SOUTH OF JAMES BAY AGAIN. UPPER RIDGES TO AGAIN
REIGN OFF THE COASTS. ..12..
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1134 PM CST MON JAN 13 2014
STRONG LOW PRESSURE SYSTEM OVER EASTERN SOUTH DAKOTA WILL MOVE RAPIDLY
SOUTHEAST REACHING SOUTHWESTERN WI TUESDAY MORNING. THE SYSTEM
WILL BRING RAPIDLY CHANGING CONDITIONS TO THE AREA LATE TONIGHT
AND TUESDAY MORNING. AROUND 09Z SNOW WILL BEGIN IN THE WEST WITH
THE SNOW SPREADING EAST TO THE MISSISSIPPI RIVER BY 12Z. AREAS
NORTH OF INTERSTATE 80 COULD SEE A BRIEF...LESS THAN ONE
HOUR...PERIOD OF FREEZING RAIN MIXED WITH THE SNOW WHILE TO THE
SOUTH SURFACE TEMPERATURES WILL BE WARM ENOUGH FOR A BRIEF
RAIN/SNOW MIX. ANY MIXED PCPN WILL QUICKLY CHANGE TO SNOW. SOME
ISOLATED THUNDER CAN/T BE RULED OUT ACROSS THE NORTH EARLY TUESDAY
MORNING. WINDS WILL BEGIN TO INCREASE AROUND MID MORNING FROM THE
NORTHWEST WITH SUSTAINED WINDS AROUND 25 KTS AND GUSTS TO AROUND
35KTS. THE STRONG WIND WITH NEW SNOWFALL WILL CAUSE BLOWING SNOW
WITH THE LOWEST CONDITIONS NORTH THROUGH THE AFTERNOON. SO IN A
NUTSHELL VFR CONDITIONS FOR A FEW HOURS AFTER MIDNIGHT THEN LOWERING
MVFR/IFR TOWARD MORNING AND CONTINUING THROUGH NOON WITH STRONG
NORTHWEST WINDS. CONDITIONS SHOULD IMPROVE TO MVFR DURING THE
AFTERNOON BUT IT WILL REMAIN QUITE WINDY. THE WIND WILL BE
DIMINISHING SOME AROUND OR JUST AFTER 00Z.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WINTER WEATHER ADVISORY FROM 5 AM TO 6 PM CST TUESDAY FOR BENTON-
BUCHANAN-CLINTON-DELAWARE-DUBUQUE-JACKSON-JONES-LINN.
IL...WINTER WEATHER ADVISORY FROM 5 AM TO 6 PM CST TUESDAY FOR
CARROLL-JO DAVIESS-STEPHENSON-WHITESIDE.
MO...NONE.
&&
$$
UPDATE...DLF
SYNOPSIS...NICHOLS
SHORT TERM...NICHOLS
LONG TERM...12
AVIATION...DLF
AREA FORECAST DISCUSSION
NWS JACKSON KY
1234 AM EST TUE JAN 14 2014
.UPDATE...
ISSUED AT 1232 AM EST TUE JAN 14 2014
THE HRRR MODEL STILL HAS A GOOD HANDLE WITH THE ONGOING PRECIPITATION
THAT HAS BEEN MOVING ACROSS CENTRAL AND EASTERN KENTUCKY THE PAST FEW
HOURS. THE FORECAST GRIDS REFLECT THIS TREND AS WELL...SO NO MAJOR
UPDATE WAS NEEDED AT THIS TIME. THE HOURLY GRIDS WERE REFRESHED A BIT
USING THE LATEST DATA...BUT ALL IN THE FORECAST LOOKS GOOD THROUGH
12Z TODAY.
UPDATE ISSUED AT 1037 PM EST MON JAN 13 2014
RAIN CONTINUES ACROSS CENTRAL AND EASTERN KY...AND ALTHOUGH IT IS
BECOMING SLIGHTLY MORE SCATTERED IN NATURE...IT DOES NOT SHOW MUCH IN
THE WAY OF EASTWARD MOVEMENT BASED ON LATEST RADAR TRENDS. AS A
RESULT...UPDATED POPS AND WEATHER TO DELAY THE EXIT OF THE RAIN ONCE
MORE. LATEST HRRR INITIATED WELL WITH ONGOING CONDITIONS...SO LEANED
TOWARDS THIS MODEL...AS WELL AS CURRENT TRENDS...TO COME UP WITH
TIMING OVER THE REST OF TONIGHT. CIGS ARE SHOWING SIGNS OF LOWERING
ACROSS THE REGION...AND EXPECT THESE LOW CLOUDS TO CONTINUE THROUGH
THE REST OF THE NIGHT. OTHERWISE...TEMPERATURES HAVE REMAINED NEARLY
STEADY...WITH ONLY MINOR UPDATES TO INCLUDE THE LATEST OBSERVATIONS
NEEDED.
UPDATE ISSUED AT 714 PM EST MON JAN 13 2014
PUSHED BACK THE TIMING OF THE EXITING RAINFALL BY A COUPLE OF
HOURS...AS LATEST RADAR RETURNS AND HI RES MODEL GUIDANCE ARE BOTH
SUPPORTING THIS TREND. IN FACT...MAY NEED TO CONTINUE TO UPDATE TO
SLOW THE TIMING EVEN MORE OVER THE NEXT FEW HOURS BASED ON THE LATEST
RADAR TRENDS. WILL CONTINUE TO MONITOR. ALSO...LATEST SOUNDINGS DO
SUGGEST MOIST CONDITIONS NEAR THE SURFACE AS DRY AIR FILTERS IN ALOFT
LATE TONIGHT INTO TOMORROW MORNING. EXPECT THIS MOISTURE TO FORM
ITSELF INTO A LOW STRATUS DECK...BUT SOME PATCHY FOG DEVELOPMENT
CANNOT BE RULED OUT...ESPECIALLY IN THE VALLEYS.
OTHERWISE...TEMPERATURES AND WINDS SEEM TO BE ON TRACK. DID BLEND IN
THE LATEST OBSERVATIONAL DATA JUST TO MAKE SURE...BUT LITTLE CHANGES
WERE MADE TO THE ONGOING FORECAST.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 322 PM EST MON JAN 13 2014
AN ACTIVE SHORT TERM FORECAST PERIOD LOOKS TO BE IN STORE AS IT WILL
BE HIGHLIGHTED BY A COUPLE OF QUICK MOVING SYSTEMS. THE 20Z ANALYSIS
ACROSS THE REGION SHOWS A COLD FRONT OVER THE GREAT LAKES AND A
DEVELOPING LOW OVER THE MID MS VALLEY BRINGING A FRONT INTO THE LOWER
OHIO VALLEY AND TN VALLEY. AHEAD OF THESE...WARMER TEMPS AND ABUNDANT
MOISTURE CONTINUE TO SURGE INTO THE AREA WITH A GOOD SWATH OF RAIN
STILL MOVING THROUGH THE STATE OF KENTUCKY AND INTO EASTERN PORTIONS.
MODELS ARE IN GOOD AGREEMENT THAT THE 500MB TROUGH WILL SWING THROUGH
EASTERN KENTUCKY BY ABOUT 14Z TUESDAY MORNING BRINGING AN END TO THE
RAINFALL. THE UPPER LEVEL PATTERN MAINTAINS ITS PROGRESSIVE
CHARACTERISTICS TO IT AS ALL THE MOISTURE EXITS THE AREA BEFORE THE
COLDER AIR IS ADVECTED IN SO NO SNOW IS EXPECTED BEHIND THIS SYSTEM.
BUT A GOOD SHOT OF MOISTURE FOR THIS EVENT WILL LEAVE A BIT HIGHER
RAINFALL TOTALS THAN ADVERTISED SO BUMPED UP QPF AMOUNTS A TAD.
HEADING INTO TUESDAY...THE PREVIOUS SYSTEM EXITS AND ANOTHER QUICK
MOVING SHORT WAVE DIVES OUT OF CANADA INTO THE OHIO VALLEY AS IT
ROTATES THROUGH THE BASE OF STUBBORN LONGWAVE TROUGH OVER THE UPPER
GREAT LAKES. THE VORT MAX WITH THIS WAVE LOOKS TO BE PRETTY STOUT AND
WITH A GOOD SHOT OF MOISTURE AS RAIN SHOWERS WILL MOVE INTO EASTERN
KENTUCKY BY TUESDAY EVENING. THE COLDER AIR WILL MOVE IN WITH THIS
FRONT QUITE QUICKLY AS RAIN SHOULD CHANGE TO SNOW BY 06Z TUESDAY
NIGHT. A GOOD BIT OF INSTABILITY WILL BE PRESENT WITH THIS FRONT AND
THE SNOW SHOWERS MAY BE HEAVY AT TIMES BUT WITH THE WARM DAYS WE HAVE
HAD...ACCUMULATIONS SHOULD BE LITTLE IF ANY AND WILL KEEP A COUPLE
TENTHS OF SNOW IN THE NORTHWEST COUNTIES. AT LEAST BY THE END OF THE
SHORT TERM FORECAST PERIOD ENDING 12Z WEDNESDAY...THIS IS ALL THE
SNOW EXPECTED RIGHT NOW. DUE TO THE GOOD INSTABILITY AND UP SLOPE
COMPONENT AVAILABLE...WILL DECIDE TO HIGHLIGHT THIS EVENT WITH AN SPS
FOR NOW...AS A WSW MAY BE NEEDED IN A FEW MORE FORECAST PERIODS.
WITH THE CONTINUED WARM SOUTHERLY FLOW...TEMPERATURES WILL REMAIN 5
TO 10 DEGREES ABOVE NORMAL THROUGH TONIGHT AND INTO TUESDAY. THE
APPROACHING FRONT TUESDAY NIGHT WILL BRING TEMPS BACK TO NORMAL
VALUES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 347 PM EST MON JAN 13 2014
MODELS START OUT IN GOOD AGREEMENT WITH A LONG WAVE OVER THE EASTERN
TWO THIRDS OF THE US. THERE IS A SHORT WAVE CENTERED OVER WISCONSIN
WHICH IS DRIVING A FRONTAL SYSTEM OUT AHEAD OF IT. ON TUESDAY NIGHT
THIS FRONT WILL MOVE THROUGH THE AREA AND THAT WILL BE FOLLOWED BY A
SURFACE TROUGH ASSOCIATED WITH THE SHORT WAVE. THIS TROUGH WILL MOVE
ACROSS THE AREA ON WEDNESDAY. BETWEEN THESE TWO SYSTEMS...THEY WILL
BE ABLE TO DROP AROUND AN INCH OF SNOW WITH UPPER ELEVATIONS MAYBE
GETTING TWO TO THREE INCHES. LOOK FOR A LULL ON THURSDAY INTO
THURSDAY NIGHT BEFORE ANOTHER COLD FRONT ARRIVES WITH ANOTHER
POTENTIAL FOR LIGHT SNOW THURSDAY NIGHT INTO FRIDAY. A CLIPPER WILL
MOVE NORTHEAST OF THE AREA...HOWEVER THE BOTTOM EDGE MAY SKIRT THE
FAR EASTERN PORTION OF THE FORECAST AREA AND BRING A SKIFF OF SNOW.
THE NEXT SYSTEM IS NOT EXPECTED TO MOVE ACROSS THE AREA UNTIL MONDAY
NIGHT. MODEL TIMING STARTS TO DIVERGE BY THE END OF THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1233 AM EST TUE JAN 14 2014
RAIN SHOWERS CONTINUE ACROSS EASTERN KY JUST AHEAD OF AN APPROACHING
COLD FRONT. THIS IS CAUSING SOME FLUCTUATION BETWEEN VFR AND MVFR
CONDITIONS. WENT AHEAD AND FORECAST FOR THE WORST CASE SCENARIO DUE
TO THIS FLUCTUATION. AS THE NIGHT CONTINUES...RAIN SHOULD TAPER OFF
FROM WEST TO EAST. HOWEVER...THE UNCERTAINTY STILL LIES AS TO WHETHER
FOG OR LOW STRATUS WILL DEVELOP AS DRY AIR FILTERS IN ALOFT AFTER THE
FRONTAL PASSAGE. IF SOME OF THE RESIDUAL MOISTURE BECOMES TRAPPED
NEAR THE SURFACE...GUIDANCE IS SHOWING A GOOD INDICATION OF MVFR TO
POSSIBLY IFR CONDITIONS DEVELOPING FOR THE LATTER PART OF THE NIGHT.
IFR CIGS ARE ALREADY BEING OBSERVED JUST UPSTREAM...AND FROM TIME TO
TIME AT THE TAF SITES.
EXPECT SKIES TO CLEAR OUT IN THE MORNING AS A BRIEF AREA OF HIGH
PRESSURE MOVES INTO THE AREA. A TIGHT PRESSURE GRADIENT BETWEEN
SYSTEMS...AND DECENT MIXING...WILL BE ENOUGH TO PRODUCE SOME HIGHER
WIND GUSTS ACROSS THE REGION. UNFORTUNATELY THIS HIGH PRESSURE WILL
BE SHORT LIVED...AS THE NEXT SYSTEM TO IMPACT THE AREA BRINGS THE
RETURN OF LOW AND MIDDLE LEVEL CLOUD COVER BY THE END OF THE TAF PERIOD.
VFR CONDITIONS SHOULD PREVAIL AT ALL THREE TAF SITES AFTER 14Z.
ISOLATED RAIN SHOWERS WILL BE POSSIBLE AT THE AIRPORTS AFTER 1Z
TONIGHT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AR
SHORT TERM...SHALLENBERGER
LONG TERM...JJ
AVIATION...AR
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
446 AM EST TUE JAN 14 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 405 PM EST MON JAN 13 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD MID/UPPER LEVEL TROUGH
FROM HUDSON BAY THROUGH THE CNTRL CONUS. A SHORTWAVE TROUGH WAS
MOVING THROUGH NRN ONTARIO BRINGING LIGHT SNOW TO LOCATIONS NORTH OF
LAKE SUPERIOR. A CLIPPER SHRTWV INTO NRN MONTANA WAS MOVING SE INTO
THE DAKOTAS. AT THE SFC...COLDER AIR WAS MOVING INTO UPPER MI
BEHIND A COLD FRONT EXTENDING FROM NRN ONTARIO THROUGH ERN UPPER MI
INTO WRN LOWER MI. A SECONDARY COLD FRONT STRETCHED FROM THE NORTH
END OF LAKE SUPERIOR INTO NRN MN. WITH 850 MB TEMPS ONLY TO AROUND
-13C OVER WRN LAKE SUPERIOR AND DRY AIR MOVING IN FROM NE
MN...LITTLE/NO LES HAS DEVELOPED INTO NW UPPER MI THROUGH 20Z.
TONIGHT...ADDITIONAL CAA DROPPING 850 MB TEMPS TO AROUND -15C SHOULD
BE ENOUGH TO BRING SOME LES FOR LOCATIONS FAVORED BY WRLY FLOW THIS
EVENING. AS WINDS VEER N TO NW OVERNIGHT...ANY LES WILL SPREAD INTO
THE REST OF WRN UPPETHE R MI AND FOR LOCATIONS FROM P53
EASTWARD. HOWEVER...THE MARGINAL INSTABILITY AND INVERSION HEIGHTS
ONLY TO 4K FT WILL LIMIT INTENSITY AND KEEP ANY ACCUMULATIONS BELOW
AN INCH.
TUESDAY...THE MODELS WERE IN RELATIVELY GOOD AGREEMENT WITH THE
CLIPPER SHRTWV MOVING TO NEAR THE SRN END OF LAKE MI BY 00Z/WED. THE
ASSOCIATED SFC LOW AND STRONGEST 700-300 QVECTOR CONV AND MID LEVEL
FGEN IS EXPECTED TO REMAIN SOUTH OF UPPER MI. HOWEVER...THE STRONGER
DYNAMICS WILL STILL BE CLOSE ENOUGH TO GRAZE THE SRN PORTION OF THE
CWA NEAR MNM WITH SEVERAL INCHES OF SNOW. QPF AMOUNTS TO AROUND 0.15
INCH WITH SLR VALUES NEAR 18/1 WOULD SUPPORT SNOW AMOUNTS TO NEAR 3
INCHES. CONFIDENCE IN SNOWFALL AMOUNTS IS STILL LIMITED SINCE THE
AREA IS ON THE NRN EDGE OF THE SIGNIFCANT QPF FCST. LES INTO THE N
CNTRL CWA NEAR P53 IS ALSO EXPECTED TO INCREASE WHERE THE CONVERGENT
NRLY FLOW IS FOCUSED. OVER THE WEST...THE LOW INVERSION HEIGHTS AND
MORE ACYC FLOW WILL ALSO REDUCE LES CHANCES/AMOUNTS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 446 AM EST TUE JAN 14 2014
A FAIRLY ACTIVE PATTERN IS IN STORE FOR THE LONG TERM PERIOD AND
LIKELY EVEN BEYOND THAT INTO THE MIDDLE OF NEXT WEEK. A RIDGE AXIS
ALONG THE WESTERN COAST OF THE CONUS AND CANADA WILL REMAIN IN PLACE
FOR MUCH OF THIS WEEK...WHILE A SERIES OF SHORTWAVES ROUND THE RIDGE
AND DIVE SOUTHEAST THROUGH THE GREAT LAKES REGION AND REINFORCE THE
UPPER TROUGH OVER THE EASTERN CONUS. WHILE THE MODELS
(GEM/GFS/ECMWF) ARE IN GREAT AGREEMENT IN THE LARGE SCALE
FEATURES...IT IS THE MESOSCALE FEATURES THAT DIFFER AND LEAD TO
UNCERTAINTY IN THE EXACT FORECAST.
WEDNESDAY...UPPER TROUGH ASSOCIATED WITH THE LOW AFFECTING PORTIONS
OF THE AREA TODAY WILL SHIFT TO THE EAST ON WEDNESDAY AND ALLOW AN
UPPER RIDGE TO QUICKLY MOVE EAST OVER THE CWA WEDNESDAY AFTERNOON
AND DEPART WEDNESDAY EVENING. AT THE SURFACE...THE DEPARTING LOW
WILL BE OVER CENTRAL LAKE HURON AT 12Z WHILE A HIGH PRESSURE RIDGE
WILL STRETCH FROM COLORADO THROUGH NORTHERN MINNESOTA. THIS WILL
LEAD TO NORTH-NORTHWEST WINDS ACROSS LAKE SUPERIOR AND WITH 850MB
TEMPS AROUND -16C THERE WILL BE ENOUGH LAKE INSTABILITY AND LOW
LEVEL MOISTURE FOR LINGERING LAKE EFFECT. BUT WITH THE SURFACE RIDGE
QUICKLY SLIDING THROUGH THE UPPER GREAT LAKES WEDNESDAY...EXPECT
WINDS TO QUICKLY BACK THROUGH THE DAY. THESE BACKING WINDS...ALONG
WITH DRIER LOW LEVEL AIR WILL BRING AN END TO THE LAKE EFFECT OVER
THE WEST AROUND EARLY AFTERNOON AND THEN OVER THE EAST BY LATE
AFTERNOON.
ATTENTION THEN SHIFTS TO THE SHORTWAVE IN THE GULF OF ALASKA THAT
IS ROUNDING THE RIDGE ALONG THE WEST COAST. THIS WAVE WILL QUICKLY
DIVE SOUTHEAST TONIGHT AND INITIAL PIECE OF UPPER LEVEL ENERGY
WILL REACH THE UPPER GREAT LAKES WEDNESDAY NIGHT. BROAD AREA OF
WARM AIR ADVECTION AHEAD OF THE SURFACE LOW WILL SPREAD LIGHT SNOW
ACROSS THE AREA WEDNESDAY NIGHT INTO THE FIRST PART OF THURSDAY
MORNING. MODEL HAVE BEEN TRENDING LOWER ON THE SNOWFALL WITH THIS
INITIAL SURGE AND HAVE FOLLOWED SUIT IN THE FORECAST (GENERAL 1-2
INCHES). IT APPEARS THAT THERE WILL BE A QUICK 3-6HR PERIOD OF LIGHT
SNOW THAT MOVES THROUGH OUT AHEAD OF THE SECONDARY WAVE AND LOW
ARRIVING MID TO LATE DAY THURSDAY. ALONG WITH THAT SNOW...EXPECT
GUSTY SOUTHWESTERLY WINDS (20-30KTS) TO PRODUCE SOME
BLOWING/DRIFTING SNOW. WITH THE LATEST TRENDS FOR SNOWFALL
AMOUNTS...DON/T THINK AN ADVISORY WILL BE NEEDED FOR THE
SYNOPTIC SNOWFALL AND BLOWING SNOW. THE BEST OPPORTUNITY FOR
ADVISORY CONDITIONS WILL BE FOR THE LAKE ENHANCEMENT OFF LAKE
MICHIGAN. DRY AIR FROM THE DEPARTING HIGH PRESSURE RIDGE WILL LIMIT
SNOW POTENTIAL WEDNESDAY EVENING...BUT IT SHOULD QUICKLY MOISTEN
AFTER 06-09Z WHEN THE SYNOPTIC PRECIPITATION ARRIVES. LOW LEVEL
WINDS LOOK TO BE MORE OUT OF THE SOUTHWEST AND THUS EXPECT THE
ENHANCEMENT TO BE FOCUSED A LITTLE FARTHER EAST THAN EXPECTED
YESTERDAY. DAY SHIFT SEEMED TO HAVE A DECENT HANDLE ON THAT IDEA
WITH IT STAYING EAST OF A LINE FROM MANISTIQUE TO TAHQUAMENON
FALLS. HAVE SNOWFALL AMOUNTS OF 3-4 INCHES IN THAT AREA AND
WITH THE GUSTY WINDS...WOULD THINK AN ADVISORY WOULD BE NEEDED
IN THE FUTURE. EXPECT THE ENHANCEMENT TO SHIFT EAST AND DIMINISH
THROUGH THE AFTERNOON AS THE WINDS BACK TOWARDS THE WEST AND LOW
LEVEL TEMPERATURES WARM.
THE MAIN QUESTION FOR THE SHORTWAVE WILL BE HOW THE LOW DIVING
SOUTHEAST FROM CANADA EVOLVES. 00Z MODELS HAVE CONTINUED THE TREND
STARTED YESTERDAY WITH A WEAKER AND MORE SOUTHWEST TRACK THROUGH
UPPER MICHIGAN. THAT SEEMS REASONABLE BASED OFF MID LEVEL
(850/700MB) POTENTIAL VORTICITY FIELDS SHOWING THE BEST ENERGY
DIVING SOUTHEAST THROUGH THE NORTHERN PLAINS AND INTO THE MID
MISSISSIPPI VALLEY THURSDAY AND THURSDAY NIGHT AS THE SECONDARY
WAVE DIVES INTO THE BACK SIDE OF THE TROUGH. IN ADDITION...THIS IS
LIKELY LEADING TO THE WEAKENING TREND TO THE SURFACE LOW AS IT
TRACKS THROUGH THE UPPER GREAT LAKES. VERY LEERY ON GETTING TOO
SPECIFIC ON THE LOW TRACK/INTENSITY AND ASSOCIATED WEATHER FEATURES
FOR THE WEDNESDAY NIGHT INTO FRIDAY PERIOD...LARGELY DUE TO THE
STRUGGLE SEEN WITH THE LOW TRACK AND ASSOCIATED PRECIP FOR THE LOW
TODAY. WAS HOPING ENSEMBLE MEMBERS WOULD HELP...BUT THEY ALL SEEM TO
SIDE WITH THEIR DETERMINISTIC RUNS AROUND 00Z FRIDAY. ALSO...SEEING
SIGNIFICANT JUMPS WITH TODAY/S SYSTEM LEADS TO MUCH LOWER CONFIDENCE
FOR THE EXACT DETAILS. UNFORTUNATELY...THE FORECAST DEPENDS ON THESE
LOW LEVEL FEATURES SINCE THE COLD AIR SURGING IN WILL LEAD TO LAKE
ENHANCEMENT AND THEN LAKE EFFECT THURSDAY AFTERNOON/EVENING INTO
FRIDAY MORNING. AT THIS POINT...WILL OPT TO TREND THE FORECAST
TOWARDS A GENERAL CONSENSUS OF THE ECMWF/GEM/UKMET AND AWAY FROM THE
STRONGER GFS AND FARTHER NORTH NAM. THIS SOLUTION WILL LIKELY LEAD
TO A LITTLE BIT OF A LULL IN THE PRECIPITATION DURING THE FIRST PART
OF THE DAY ON THURSDAY (AND POTENTIALLY THE ENTIRE DAY)...BEFORE THE
LOW MOVES THROUGH THE UPPER GREAT LAKES AREA AND SHIFTS WINDS TO THE
NORTH-NORTHWEST AND REALLY DEVELOPS THE LAKE ENHANCED AND THEN
EFFECT SNOW. THE LAKE EFFECT THURSDAY NIGHT INTO FRIDAY IS PROBABLY
THE MOST CERTAIN PART OF THE FORECAST AND WILL CONTINUE THE DEFINITE
POPS IN THE FAVORED SNOW BELTS. AMOUNTS WILL LARGELY DEPEND ON THE
INTENSITY/POSITION OF THE LOW (WHICH LOOKS TO SLOW OVER NORTHERN
LOWER MICHIGAN FRIDAY MORNING) AND THE ENHANCED CONVERGENCE
ASSOCIATED WITH IT. THUS...WITH THE FAVORABLE LAKE ENHANCED/EFFECT
CONDITIONS...HAVE TRENDED THE SNOWFALL AMOUNTS UP TO BE IN THE 3-6IN
RANGE FOR LOCATIONS NEAR LAKE SUPERIOR. WHEN FACTORING IN SOME
BLOWING AND DRIFTING WITH THE WINDS (20-35MPH NEAR LAKE
SUPERIOR)...THINK AT LEAST ADVISORIES WILL ALSO BE NEEDED AT SOME
POINT AND WILL CONTINUE TO MENTION IN THE HWO. WITH THE WEAKER
LOW PRODUCING A LITTLE LIGHTER WINDS...WILL TREND TOWARDS
LESS HARSH WORDING.
PAST THIS SYSTEM...APPEARS THAT THERE WILL BE ANOTHER COUPLE
SHORTWAVES/CLIPPERS MOVING THROUGH THE AREA FOR THE WEEKEND INTO
NEXT WEEK. ONE LOOKS TO MOVE THROUGH THE NORTHERN PLAINS AND MID
MISSISSIPPI VALLEY ON FRIDAY NIGHT AND SATURDAY AND ANOTHER
BRUSHING THE NORTHEAST PART OF THE UPPER GREAT LAKES REGION ON
SATURDAY NIGHT AND SUNDAY. MODELS VARY ON 850MB TEMPS DURING THIS
PERIOD...WITH A TREND TOWARDS WARMER VALUES OVER THE LAST 2-4
RUNS. WITH THE UNCERTAINTY...FOLLOWED A GENERAL CONSENSUS OF THE
MODELS WITH SOME INCREASE IN POPS WHEN LAKE EFFECT IS EXPECTED. THE
SECOND CLIPPER WILL SWEEP A COLD FRONT ACROSS UPPER MICHIGAN ON
SUNDAY AND LEAD TO ANOTHER PERIOD OF LAKE EFFECT SNOW. SHOULD SEE
A WEAK RIDGE BUILD OVER THE AREA FOR MONDAY BUT THEN ANOTHER
CLIPPER SYSTEM NEARS THE AREA ON MONDAY NIGHT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1156 PM EST MON JAN 13 2014
EXPECT MVFR CONDITIONS AT ALL TAF SITES THROUGH THE PERIOD AS LAKE
EFFECT SNOW SHOWERS CONTINUE AT IWD AND CMX.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 405 PM EST MON JAN 13 2014
GUSTY WEST WINDS TO 30 KTS THROUGH THE EVENING DIMINISH TO 25 KTS ON
TUESDAY WHILE BECOMING NORTHWEST. EXPECT THE WINDS TO DIMINISH
BRIEFLY LATE TUESDAY NIGHT INTO WEDNESDAY AFTERNOON AS A HIGH
PRESSURE RIDGE CROSSES THE REGION. LOW PRESSURE CROSSING LAKE
WINNIPEG LATE WEDNESDAY AFTERNOON WILL THEN SINK ACROSS LAKE
SUPERIOR ON THURSDAY. EXPECT SW GALES OF 35-40KTS WEDNESDAY NIGHT
OVER EASTERN SECTIONS. N-NW GALES OF 35 KTS ARE POSSIBLE LATE
THURSDAY AFTERNOON THROUGH FRIDAY MORNING IN WAKE OF A COLD
FRONT FOLLOWING THE LOW. THE LOW WILL WEAKEN AS IT DRIFTS EASTWARD
INTO SOUTHERN ONTARIO THROUGH THE DAY FRIDAY...WHILE KEEPING A WEAK
TROUGH OVER LAKE SUPERIOR. HEAVY FREEZING SPRAY
WILL BE POSSIBLE THURSDAY NIGHT THROUGH FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY FROM 7 AM THIS MORNING TO 9 PM CST THIS
EVENING FOR MIZ012.
LAKE EFFECT SNOW ADVISORY FROM 1 PM THIS AFTERNOON TO 7 AM EST
WEDNESDAY FOR MIZ006.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM 7 PM THIS EVENING TO 1 PM EST
WEDNESDAY FOR LSZ248>251-265>267.
HEAVY FREEZING SPRAY WARNING FROM 7 PM THIS EVENING TO 7 AM EST
WEDNESDAY FOR LSZ244-245-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...07
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1157 PM EST MON JAN 13 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 405 PM EST MON JAN 13 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD MID/UPPER LEVEL TROUGH
FROM HUDSON BAY THROUGH THE CNTRL CONUS. A SHORTWAVE TROUGH WAS
MOVING THROUGH NRN ONTARIO BRINGING LIGHT SNOW TO LOCATIONS NORTH OF
LAKE SUPERIOR. A CLIPPER SHRTWV INTO NRN MONTANA WAS MOVING SE INTO
THE DAKOTAS. AT THE SFC...COLDER AIR WAS MOVING INTO UPPER MI
BEHIND A COLD FRONT EXTENDING FROM NRN ONTARIO THROUGH ERN UPPER MI
INTO WRN LOWER MI. A SECONDARY COLD FRONT STRETCHED FROM THE NORTH
END OF LAKE SUPERIOR INTO NRN MN. WITH 850 MB TEMPS ONLY TO AROUND
-13C OVER WRN LAKE SUPERIOR AND DRY AIR MOVING IN FROM NE
MN...LITTLE/NO LES HAS DEVELOPED INTO NW UPPER MI THROUGH 20Z.
TONIGHT...ADDITIONAL CAA DROPPING 850 MB TEMPS TO AROUND -15C SHOULD
BE ENOUGH TO BRING SOME LES FOR LOCATIONS FAVORED BY WRLY FLOW THIS
EVENING. AS WINDS VEER N TO NW OVERNIGHT...ANY LES WILL SPREAD INTO
THE REST OF WRN UPPETHE R MI AND FOR LOCATIONS FROM P53
EASTWARD. HOWEVER...THE MARGINAL INSTABILITY AND INVERSION HEIGHTS
ONLY TO 4K FT WILL LIMIT INTENSITY AND KEEP ANY ACCUMULATIONS BELOW
AN INCH.
TUESDAY...THE MODELS WERE IN RELATIVELY GOOD AGREEMENT WITH THE
CLIPPER SHRTWV MOVING TO NEAR THE SRN END OF LAKE MI BY 00Z/WED. THE
ASSOCIATED SFC LOW AND STRONGEST 700-300 QVECTOR CONV AND MID LEVEL
FGEN IS EXPECTED TO REMAIN SOUTH OF UPPER MI. HOWEVER...THE STRONGER
DYNAMICS WILL STILL BE CLOSE ENOUGH TO GRAZE THE SRN PORTION OF THE
CWA NEAR MNM WITH SEVERAL INCHES OF SNOW. QPF AMOUNTS TO AROUND 0.15
INCH WITH SLR VALUES NEAR 18/1 WOULD SUPPORT SNOW AMOUNTS TO NEAR 3
INCHES. CONFIDENCE IN SNOWFALL AMOUNTS IS STILL LIMITED SINCE THE
AREA IS ON THE NRN EDGE OF THE SIGNIFCANT QPF FCST. LES INTO THE N
CNTRL CWA NEAR P53 IS ALSO EXPECTED TO INCREASE WHERE THE CONVERGENT
NRLY FLOW IS FOCUSED. OVER THE WEST...THE LOW INVERSION HEIGHTS AND
MORE ACYC FLOW WILL ALSO REDUCE LES CHANCES/AMOUNTS.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 405 PM EST MON JAN 13 2014
LARGE SCALE PATTERN THROUGH THE EXTENDED INDICATES A RIDGE OVER
THE WESTERN CONUS AND WESTERN CANADA WHILE TROUGHING DOMINATES
MUCH OF THE EASTERN CONUS...INCLUDING THE GREAT LAKES. STRONGEST
WAVE WITHIN THE TROUGH CROSSES THE UPPER GREAT LAKES WEDNESDAY NIGHT
THROUGH FRIDAY. DAYTIME HIGHS WILL END UP BLO NORMAL FOR MUCH OF
THE TIME...BUT NOT BY THAT MUCH. WARMEST DAY APPEARS TO BE ON
THURSDAY AHEAD OF STRONGER COLD FRONT. WARMING TREND DEVELOPS AT
THE VERY END OF THE EXTENDED...THOUGH HOW QUICK THAT OCCURS IS
STILL UNCERTAIN AS ECMWF/GFS SHOW LIMITED CONSISTENCY IN HOW FAST
TO EXIT THE LARGER SCALE TROUGH AT THAT TIME RANGE.
TUESDAY NIGHT INTO WEDNESDAY...LAKE EFFECT NEAR LK SUPERIOR MAINLY
FOR AREAS FAVORED BY NNW WINDS. IN THE LARGE SCALE...HIGH PRESSURE
RESULTS IN NEUTRAL TO ANTICYCLONIC FLOW AND INVERSION HEIGHTS TO
5KFT. CONVERGENCE STRONGEST OVER ALGER AND NORTHERN SCHOOLCRAFT
AND MAJORITY OF CONVECTIVE LAYER WILL BE WITHIN DGZ. ADVY LEVEL SNOW
COULD OCCUR BUT WOULD PROBABLY BE SPREAD FM LATE AFTN ON TUESDAY
THROUGH MIDDAY ON WEDNESDAY. LIKELY WILL BE LAKE EFFECT OVER WESTERN
SNOWBELTS TOO...BUT SINCE THAT AREA IS FARTHER INTO AFFECTS OF SFC
HIGH...INTENSITY/ACCUMS SHOULD BE MINIMAL. LAKE EFFECT SHOULD LINGER
OVER ALGER COUNTY UNTIL LATE WEDNESDAY AFTN ONCE WINDS IN THE BLYR
FINALLY BECOME WEST OR SOUTHWEST AS SFC-H85 RIDGE CROSSES UPPER GREAT
LAKES. EVEN WITH WARMING AT H85...COOLER AIR LINGERS BLO...SO TEMPS
ON WEDNESDAY WILL STAY SIMILAR TO READINGS ON TUESDAY MAINLY IN THE
TEENS.
WEDNESDAY NIGHT INTO THURSDAY...ATTN IS ON STRONG SHORTWAVE DIGGING
FM SOUTHERN PORTIONS OF SASKATCHEWAN AND MANITOBA TO THE NORTHERN
PLAINS BY EARLY WEDNESDAY EVENING. SHORTWAVE DIGS INTO UPPER
MISSISSIPPI RIVER VALLEY BY THURSDAY MORNING WHILE ASSOCIATED SFC
LOW MOVES VCNTY OF WESTERN LK SUPERIOR. DECENT AGREEMENT THAT H85-H7
WARM AND MOIST ADVECTION/ISENTROPIC ASCENT 280-285K WILL SUPPORT
SWATH OF LGT SNOW ACROSS MUCH OF CWA. MIXING RATIOS AT H7 ONLY NEAR
1.5G/KG SO OVERALL THE SYNOPTIC SNOW WILL BE LIMITED TO 1-3 INCHES.
COUPLE OF ITEMS TO NOTE THOUGH. FIRST IS POTENTIAL FOR LAKE ENHANCED
SNOW DOWNWIND OF LAKE MICHIGAN. SSW WINDS IN BLYR WITH H85 TEMPS
AROUND -12C ON WEDNESDAY NIGHT RESULT IN THIS POTENTIAL. AS IT LOOKS
NOW...AREAS MAINLY TO EAST OF KISQ AND TOWARD KERY WOULD BE FAVORED
03Z-15Z THURSDAY. SLR/S PROBABLY IN THE 13-16:1 RANGE AS GFS
SOUNDINGS SHOW ISOTHERMAL LAYER FM H9 TO H75 AROUND -13C. SEEMS
THAT ADVY SNOWS COULD OCCUR IN THIS TYPE OF SETUP. SECOND ISSUE IS
POTENTIAL FOR GUSTY WINDS OVER THE CWA AS THE SNOW IS
OCCURRING...ADDING A BIT MORE OF AN IMPACT TO THE OTHERWISE LGT SNOW
ACCUMS. GFS AND ECMWF BOTH POINT TO WINDS GUSTING 25-30 KTS AS THE
SNOW OCCURS WITH STRONG PRESSURE FALLS SPREADING ACROSS LK
SUPERIOR...ESPECIALLY WEDNESDAY EVENING...BEFORE THE LOW MAY START
TO WEAKEN LATER WEDNESDAY NIGHT. PRETTY CERTAIN THAT SOME HEADLINES
MAY BE NEEDED...WITH THE HIGHEST CERTAINTY COMING OVER THE SE ZONES
DUE TO LAKE ENHANCEMENT AND BLSN CLOSER TO LK MICHIGAN SHORE. IF
STRONGER FORCING WAS PRESENT FOR LONGER DURATION AND AIRMASS IN THE
LOW-LEVEL SSW FLOW WAS COLDER...COULD EVEN SEE NEED FOR WARNING. NOT
SURE IF HEADLINES WILL BE NEEDED ELSEWHERE SINCE SNOW AMOUNTS ARE ON
LOWER SIDE AND SINCE ONLY EXPECTING MARGINALLY STRONG WIND GUSTS (30
KTS IN BLYR VERSUS 50 KTS). CANNOT COMPLETELY RULE THAT OUT THOUGH.
BY DAYBREAK THURSDAY AND BEYOND...GFS/ECMWF/GEM-NH NOT SURE HOW
THINGS EVOLVE INTO THURSDAY NIGHT. LOOKS LIKE PREVIOUS RUNS OF ECMWF
AND GEM-NH WERE STRONGER WITH THE SFC LOW WHILE THE 12Z GFS TRENDED
STRONGER. GFS DOES ALSO SHOW THE LOW EVENTUALLY FILLING LATER ON
THURSDAY AS IT CROSSES THE REGION. UNCERTAINTY MAINLY IMPACTS THE
WIND FIELDS ON BACK SIDE OF THE LOW WHEN COLD FRONT CROSSES LK
SUPERIOR AND UPR MICHIGAN. COLD AIR ADVECTION IS STRONG BUT THE
REALLY STRONG WINDS WOULD BE MITIGATED SOME WITHOUT TIGHTER SFC
PRESSURE GRADIENT. NOTHING CERTAIN THOUGH...ESPECIALLY GIVEN MODEL
INCONSISTENCY. STRONGER SYSTEM WOULD RESULT IN MORE CONSIDERABLE
BLSN OVER EXPOSED AREAS NEAR LK SUPERIOR...MAINLY IN THE WESTERN
CWA AS MORE ICE IS BUILT UP IN THOSE AREAS CLOSER TO THE SHORE.
LAKE EFFECT THAT DEVELOPS IN WAKE OF THE COLD FRONT PROBABLY GETS
A BOOST INTO FRIDAY AS MID-LEVEL TROUGH AXIS AND H85-H7 CROSS THE
AREA. WIND DIRECTION NOT CLEAR THOUGH AS WEAKER SYSTEM AS ECMWF
SHOWS RESULTS IN NW FLOW LAKE EFFECT WHILE GFS AND TO SOME EXTENT
THE GEM-NH WOULD IMPACT N/NE FLOW AREAS THURSDAY NIGHT THEN SWITCH
TO MORE OF A N/NW FLOW AREAS ON FRIDAY. WINDS BACKING LATER FRIDAY
INTO FRIDAY NIGHT ALONG WITH TEMPS IN LOW-LEVELS WARMING SLIGHTLY
SHOULD DIMINISH LINGERING LAKE EFFECT BY SATURDAY.
REST OF EXTENDED...AS ALLUDED TO EARLIER THE FCST FOR LATE IN THE
WEEKEND INTO EARLY NEXT WEEK IS UNCERTAIN WITH HANDLING OF EXITING
OF LARGER SCALE TROUGH. 12Z ECMWF BACK TO SHOWING ONE LAST PUSH OF
CHILLY AIR LATER SUNDAY INTO MONDAY WITH H85 TEMPS BLO -20C. 00Z
ECMWF HAD THIS COLD AIR PUSH WELL TO THE NORTH...WITH TEMPS NEARING
0C AT H85 PUSHING INTO WESTERN GREAT LAKES. MEANWHILE...LATEST GFS
LOOKS LIKE 00Z ECMWF RUN FM LAST NIGHT WITH WARMING SPREADING INTO
UPR LAKES TO CLOSE NEXT WEEKEND. RAN WITH MODEL CONSENSUS FOR THE
GRIDS UNTIL TIMING/WESTERN EXTENT OF LARGER SCALE TROUGH CAN BE
WORKED OUT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1156 PM EST MON JAN 13 2014
EXPECT MVFR CONDITIONS AT ALL TAF SITES THROUGH THE PERIOD AS LAKE
EFFECT SNOW SHOWERS CONTINUE AT IWD AND CMX.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 405 PM EST MON JAN 13 2014
GUSTY WEST WINDS TO 30 KTS THROUGH THE EVENING DIMINISH TO 25 KTS ON
TUESDAY WHILE BECOMING NORTHWEST. EXPECT THE WINDS TO DIMINISH
BRIEFLY LATE TUESDAY NIGHT INTO WEDNESDAY AFTERNOON AS A HIGH
PRESSURE RIDGE CROSSES THE REGION. LOW PRESSURE CROSSING LAKE
WINNIPEG LATE WEDNESDAY AFTERNOON WILL THEN SINK ACROSS LAKE
SUPERIOR ON THURSDAY. EXPECT SW GALES OF 35-40KTS WEDNESDAY NIGHT
OVER EASTERN SECTIONS. N-NW GALES OF 35 KTS ARE POSSIBLE LATE
THURSDAY AFTERNOON THROUGH FRIDAY MORNING IN WAKE OF A COLD
FRONT FOLLOWING THE LOW. THE LOW WILL WEAKEN AS IT DRIFTS EASTWARD
INTO SOUTHERN ONTARIO THROUGH THE DAY FRIDAY...WHILE KEEPING A WEAK
TROUGH OVER LAKE SUPERIOR. HEAVY FREEZING SPRAY
WILL BE POSSIBLE THURSDAY NIGHT THROUGH FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...07
MARINE...JLA
AREA FORECAST DISCUSSION
NWS RALEIGH NC
117 AM EST TUES JAN 14 2014
.SYNOPSIS...A LOW PRESSURE SYSTEM WILL CROSS THE CAROLINAS LATE
TONIGHT AND TUESDAY. AN ARCTIC COLD FRONT WILL CROSS THE REGION ON
WEDNESDAY.
&&
.NEAR TERM /TONIGHT THROUGH TUESDAY MORNING/...
AS OF 948 PM MONDAY...
TONIGHT THROUGH TUESDAY MORNING...
WEAK S/W VORT DISTURBANCES EMBEDDED IN THE SWLY FLOW ALOFT IN
ADVANCE OF AN ELONGATED POSITIVE TILTED S/W TROUGH THAT EXTENDS FROM
SOUTHERN ONTARIO SOUTHWARD INTO THE SOUTHERN PLAINS WILL EJECT NEWD
AND ACROSS THE CAROLINAS OVERNIGHT. BAND OF PRE-FRONTAL SHOWERS IS
JUST NOW STARTING TO FILL IN EAST OF THE MOUNTAINS...TAKING SOME
TIME TO OVERCOME THE DRY AIR IN PLACE(PWATS 0.3-0.5"). WHILE BROAD
MOISTENING WILL SEND PWATS TO 1.0" IN THE WEST TO 1.2" IN THE
EAST...THE STRONG/BETTER LOW-LEVEL MOISTURE TRANSPORT IS FORECAST TO
REMAIN ACROSS SOUTHERN COASTAL SECTIONS OF THE CAROLINAS...IN
PROXIMITY TO A WEAK SFC WAVE DEVELOPING ALONG THE EASTWARD ADVANCING
COLD FRONT. THIS WILL RESULT IN VERY LIGHT RAINFALL AMOUNTS MUCH OF
THE FORECAST AREA WITH ALL OF THE HI-RES CAM MODELS AND RAP SHOWING
THE RAIN BAND MOVING EASTWARD IN A WEAKENING/FRAGMENTED STATE.
POPS OVERNIGHT INTO TUESDAY MORNING VARY FROM LOW END LIKELY NW TO
CATEGORICAL GENERALLY ALONG AND EAST OF I-95. MIN TEMPS RELATIVELY
MILD FOR JANUARY...RANGING FROM MID 40S NW TO AROUND SE.
&&
.SHORT TERM /TUESDAY AFTERNOON THROUGH WEDNESDAY NIGHT/...
AS OF 335 PM MONDAY...
TUESDAY AFTERNOON AND TUESDAY NIGHT...
MID LEVEL TROUGH AND ASSOCIATED SFC BOUNDARY WILL CROSS CENTRAL
NC TUESDAY MORNING...EXITING OUR COASTAL PLAIN COUNTIES EARLY TUESDAY
AFTERNOON. W-NW WINDS BEHIND THE EXITING TROUGH WILL ADVECT DRIER
STABLE AIR INTO OUR REGION. THE ARRIVAL OF THIS AIRMASS WILL AID TO
DIMINISH SHOWER COVERAGE WEST-TO-EAST ACROSS CENTRAL NC. THIS
DECREASING POP TREND WILL OCCUR IN THE WESTERN PIEDMONT BY LATE
MORNING...PROGRESSING INTO THE COASTAL PLAIN BY MID AFTERNOON.
APPEARS THAT SKIES MAY BE ABLE TO CLEAR OUT IN THE WESTERN PIEDMONT
TO ALLOW FOR PARTIAL SUNSHINE WITH MOSTLY CLOUDY SKIES EAST AND
PARTIAL SUN WEST SHOULD YIELD A UNIFORM MAX TEMPS FILED TUESDAY.
DOWNSLOPE WARMING DUE TO W-NW LOW LEVEL FLOW WILL OFFSET INITIAL
COLD AIR ADVECTION. MAX TEMPS UPPER 50S NW TO LOWER 60S SE.
DRIER AND NOTICEABLY COOLER AIRMASS WITH WEAK SFC RIDGE QUICKLY
TRANSLATING EAST. MIN TEMPS GENERALLY IN THE MID 30S.
WEDNESDAY AND WEDNESDAY NIGHT...
LATEST GFS/ECMWF HAVE COME INTO DECENT AGREEMENT WITH THEIR DEPICTION
OF A DEEP L/W TROUGH INITIALLY EXTENDING FROM THER GREAT LAKES SWD
INTO THE DEEP SOUTH...ADVANCING INTO THE CAROLINAS BY EARLY THURSDAY.
A S/W ROUNDING THE BASE OF THE TROUGH WILL LIFT NEWD ALONG THE SPINE
OF THE APPALACHIANS WEDNESDAY. THIS FEATURE WILL INDUCE THE FORMATION
OF A SFC TROUGH IN THE LEE OF THE MOUNTAINS WITH A SFC WAVE OVER WESTERN
NC. THE EXPECTED TRACK OF THE S/W AT THIS TIME SUGGEST THE BEST CHANCE FOR
PRECIP WILL BE IMMEDIATELY WEST OF OUR REGION...MORE SO IN THE MOUNTAINS.
ONCE THIS S/W LIFTS NWD INTO THE CENTRAL APPALACHIANS...AN ARCTIC COLD
FRONT WILL SWEEP ACROSS OUR REGION WEDNESDAY AFTERNOON. SINCE IT NOW
APPEARS THAT THE PIEDMONT WILL BE ON THE WARM SECTOR OF THE LOW...
ANY SHOWERS THAT OCCUR SHOULD BE MAINLY LIQUID. BEHIND THE BOUNDARY...
POTENTIAL FOR A FEW SNOWFLAKES TO MIX IN WITH THE RAIN SHOWERS AS THE
COLDER AIR ALOFT BECOMES DEEPER/CLOSER TO THE SURFACE.
BEST FORCING FOR RAIN SHOWERS APPEAR TO BE ACROSS THE NW-NORTHERN
PIEDMONT WITH SHALLOWER MOISTURE AND LIFT FARTHER SOUTH. WILL VARY
POPS FROM CHANCE NW TO SLIGHT CHANCE SOUTH. DID ADJUST MAX TEMPS UP
3-5 DEGREES FROM PREVIOUS FORECAST DUE TO SLOWER FRONTAL PASSAGE.
MAX TEMPS MID 40S NW TO LOWER 50S SE. IF RAIN SHOWERS HOLD OFF AND
FRONTAL PASSAGE BECOMES SLOWER...MAX TEMPS MAY NEED TO BE RAISED
ANOTHER 3-5 DEGREES.
AS THE S/W APPROACHES THE COAST WEDNESDAY NIGHT...ANOTHER SURFACE
LOW WILL DEVELOP AND STRENGTHEN OFFSHORE. THE WRAP AROUND FROM THIS
SYSTEM MAY CAUSE A FEW SNOW SHOWERS ACROSS THE NORTHERN HALF OF THE
COASTAL PLAIN AND POSSIBLY AS FAR WEST AS THE TRIANGLE AREA. THE
ECMWF STILL FAVORS A MORE INLAND INFLUENCE COMPARED TO THE GFS WHICH
REMAINS VERY PROGRESSIVE. CONSIDERING THE PROBABLE BAROCLINICITY
THAT MAY EXIST OFFSHORE...LEANED TOWARD THE ECMWF. THUS EXPECT A FEW
SNOW SHOWERS BUT NOT ENOUGH AT THIS TIME TO RAISE ANY CONCERNS. MIN
TEMPS MID 20S WHERE SKIES WILL CLEAR OFF EARLY IN THE EVENING TO
NEAR 30 IN THE EAST.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 335 PM MONDAY...
THURSDAY AND THURSDAY NIGHT...
BROAD UPPER TROUGH WILL AMPLIFY/DIG SWD AS A POTENT S/W ADVANCES
SEWD ON THE BACK SIDE OF THE TROUGH. THIS WILL CAUSE THE MID-UPPER
FLOW TO BACK TO A SW DIRECTION AND ADVECT MOISTURE INTO OUR REGION
BY THURSDAY EVENING...MAINLY IN THE UPPER REACHES OF THE ATMOSPHERE.
CLEAR TO PARTLY CLOUDY SKIES EARLY THURSDAY SHOULD BECOME PARTLY-
MOSTLY CLOUDY BY LATE IN THE DAY AND INTO THURSDAY NIGHT. PRESENCE
OF STRONG UPPER TROUGH WILL HOLD COOL AIRMASS IN PLACE. MAX TEMPS
THURSDAY MAINLY IN THE LOW-MID 40S. MIN TEMPS THU NIGHT IN THE UPPER
20S-LOWER 30S. -WSS
FRIDAY THROUGH MONDAY: ANOTHER POTENT DIGGING S/W ALOFT WILL HELP
AMPLIFY THE MID LEVEL TROUGH OVER THE EASTERN U.S. AGAIN ON
FRIDAY... AND SEND ANOTHER COLD FRONT ACROSS OUR AREA FRIDAY INTO
FRIDAY EVENING. MEDIUM RANGE MODELS CONTINUE TO STRUGGLE WITH REGARD
TO THE AMPLIFICATION AND TIMING OF THIS MID LEVEL TROUGH THOUGH. THE
GFS AND MOST OF ITS ENSEMBLE MEMBERS KEEP US DRY WITH THIS SYSTEM.
HOWEVER... THE LAST FEW RUNS OF THE OPERATIONAL ECMWF ARE SHOWING
SOME PRECIP WITH THIS SYSTEM... ALONG AND BEHIND THE COLD FRONT...
WITH SOME OF THE PRECIP FALLING AS SNOW. FOR NOW WILL ONLY INTRODUCE
A SLIGHT CHANCE OF PRECIP LATE FRIDAY INTO FRIDAY NIGHT GIVEN THE
UNCERTAINTY. DRY WEATHER IS EXPECTED TO RETURN FOR NEXT WEEKEND...
ALTHOUGH TEMPS ARE EXPECTED TO BE BELOW NORMAL... GENERALLY IN THE
30S AND 40S (ESPECIALLY ON SATURDAY). WITH SURFACE HIGH PRESSURE
MOVING ACROSS THE NORTHERN GULF OF MEXICO LATE SUNDAY INTO MONDAY...
TEMPS ARE EXPECTED TO WARM BACK TO NORMAL FOR MONDAY. -BSD
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 115 AM TUESDAY...
PERIODS OF LIGHT RAIN WILL CONTINUE THROUGH TUESDAY AFTERNOON AHEAD
OF A COLD FRONT APPROACHING FROM THE WEST. CONDITIONS WILL BECOME
MVFR OVER THE NEXT FEW HOURS ACROSS THE AREA... WITH THE POTENTIAL
FOR IFR CONDITIONS AFTER 10Z. VFR CONDITIONS WILL RETURN FROM WEST
TO EAST... WITH RAPID CLEARING AFTER THE FRONT PASSES THROUGH THE
AREA BETWEEN 18Z TUES AND 00Z WED.
OUTLOOK... A COLD FRONT WILL CROSS NC ON WEDNESDAY...BRINGING
ANOTHER PERIOD OF SUB-VFR CONDITIONS AND A CHANCE OF PRECIP. VFR
CONDITIONS ARE THEN EXPECTED ON THURSDAY BEFORE YET ANOTHER SYSTEM
CROSSES THE AREA LATE FRIDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...CBL
SHORT TERM...WSS
LONG TERM...WSS/NP/BSD
AVIATION...SEC/SMITH
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
113 AM EST TUE JAN 14 2014
.SYNOPSIS...
A COLD WILL MOVE OFF THE CAROLINA COAST THIS AFTERNOON AS ANOTHER
COLD FRONT CROSSES TENNESSEE. EXPECT THIS COLD FRONT TO BRING MAINLY
MOUNTAIN SNOW SHOWERS TUESDAY NIGHT THROUGH WEDNESDAY NIGHT BEFORE
DRY HIGH PRESSURE RETURNS BRIEFLY FOR THURSDAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 110 AM EST TUESDAY...LATEST RADAR IMAGERY CONTINUES TO
INDICATE WIDESPREAD LIGHT SHOWERS ACROSS THE REGION AS THE COLD
FRONT REMAINS WELL TO THE WEST ACROSS MIDDLE TENNESSEE. THEREFORE
OPTED NOT TO MAKE ANY CHANGES TO THE POPS IN THE EXTREME NEAR TERM
AS THEY LOOK IN LINE WITH THE LATEST TRENDS. WIDESPREAD CLOUDINESS
CONTINUES TO PREVAIL WITH CEILINGS LOWERING FROM WEST TO EAST AS THE
HEAVIEST SHOWER ACTIVITY EXITS INTO THE CENTRAL NC PIEDMONT AND SC
MIDLANDS/LOWCOUNTRY PER LATEST SATELLITE DIFFERENCE PRODUCT.
OTHERWISE... TWEAKED TEMPERATURES AND DEWPOINTS TO REFLECT LATEST
TRENDS AND LEFT THE REMAINDER OF THE FORECAST AS IS WITH NO MAJOR
CHANGES.
PREVIOUS DISCUSSION...
630 PM UPDATE...AS UPPER TROUGH CONTINUES TO SWING INTO THE LOWER
MISSISSIPPI VALLEY...THE PREFRONTAL BAND OF LIGHT RAIN HAS NOW
TRANSLATED EAST AND IS SET TO AFFECT MAINLY THE PIEDMONT. SW FLOW
STILL SUGGESTED BY POSITION OF TROUGH ON WV IMAGERY AND IS SEEN IN
LOWER LEVELS ON VAD WINDS FROM RADAR ACRS THE AREA. DPVA AHEAD OF
THE WAVE CONTINUES TO DRIVE LIGHT SHOWER ACTIVITY OVER THE ERN HALF
OF TENN AND NRN ALABAMA. THUS EVEN AREAS WEST OF THE MAIN RAIN BAND
STILL HAVE A GOOD CHANCE AT SEEING RAINFALL. LATEST RAP QPF SUGGESTS
THE BAND WILL GRADUALLY WEAKEN AS IT MOVES NE...BUT WITH SW FLOW
CONTINUING AND THE S/W STILL MOVING IN...PRECIP IS REINTRODUCED FROM
THE WEST.
AS OF 215 PM...A 500 MB POSITIVELY-TILTED SHORTWAVE TROF WILL
QUICKLY CROSS THE REGION TUESDAY MORNING...PUSHING A WEAK COLD FRONT
THRU THE AREA. A BAND OF GENERALLY LIGHT RAIN WILL WORK ACRS THE
CWFA FROM WEST TO EAST OVERNIGHT AHEAD OF THE FRONT...FORCED MAINLY
BY RIGHT FRONT QUADRANT UPR DIVERGENCE AND LLVL ISENT LIFT. THE
LIMITING FACTORS FOR BETTER RAIN RATES APPEAR TO BE WEAK MID LVL
LAPSE RATES AND MOISTURE TRANSPORT THAT WILL BE SIPHONED OFF BY
CONVECTION ALONG THE GULF COAST. GIVEN THE STRONG UPR SUPPORT...WILL
CARRY LIKELY TO CATEGORICAL POPS OVERNIGHT...WITH QPF IN THE TENTH
TO QUARTER INCH RANGE. SWLY FLOW UPSLOPE AREAS MAY SEE LOCALLY
HIGHER AMOUNTS. LLVL CAA WILL BEGIN TO RAMP UP AS PRECIP TAPERS OFF
EARLY TUESDAY MORNING. SO A BRIEF CHANGEOVER TO SNOW IS POSSIBLE
ABOVE 3500 FT...BUT LITTLE TO NO ACCUM IS EXPECTED. TEMPS WILL BE
ABOVE NORMAL OVERNIGHT WITH CLOUDS/PRECIP.
UPR JET AND SHORTWAVE WILL EXIT TO THE EAST BY MIDDAY
TUESDAY...ALLOWING FOR CLEARING SKIES AND END TO PRECIP. THICKNESSES
FALL LITTLE BEHIND THE FRONT...WITH DOWNSLOPE FLOW LIKELY CANCELING
OUT LLVL CAA. SO I BLENDED IN THE WARMER MET FOR MAX TEMPS.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY/...
AS OF 2 PM MONDAY...THE SHORT TERM FCST PICKS UP AT 00Z ON WEDNESDAY
WITH DEEP UPPER TROFFING DIGGING DOWN OVER THE MISS RIVER VALLEY AND
STEEP UPPER RIDGING OVER THE FAR WESTERN CONUS. THE TROF AXIS WILL
LIKELY AMPLIFY AS IT APPROACHES THE CAROLINAS AND SHOULD MOVE OVER
THE CWFA BY EARLY THURS. AS THE AXIS LIFTS NE OF THE AREA ON THURSDAY
AFTERNOON...THE UPPER TROF IS REINFORCED AND DEEPENS AGAIN JUST TO
OUR WEST AS WE MOVE INTO FRIDAY.
ON WEDNESDAY...ANOTHER...STRONGER COLD FRONT WILL APPROACH THE CWFA
EARLY WED MORNING. A NARROW BAND OF MOISTURE ACCOMPANYING THIS SURGE
OF COLD AIR WILL BRING INCREASING PRECIP CHANCES ACROSS THE WESTERN
MTNS BY DAYBREAK...WITH FCST PARTIAL THICKNESSES AND FCST SOUNDINGS
CONTINUING TO SUGGEST AN ALL RAIN OR SNOW EVENT. THE SYNOPTIC
FORCING WILL SHIFT RAPIDLY TO THE EAST DURING THE MORNING...WITH A
TRANSITION TO A NW FLOW SNOW SCENARIO EXPECTED BY MID TO LATE
AFTERNOON. OVERALL SNOWFALL AMOUNTS HAVE DECREASED FOR THE NC/TENN
BORDER REGION COMPARED TO THE PREVIOUS FCST WITH MOST LOCATIONS
EXPECTED TO RECEIVE 1 TO 3 INCHES THRU THURS MORNING. TEMPS WILL
COOL MARKEDLY BEHIND THE FROPA WITH HIGHS REACHING THE MID TO UPPER
40S FOR THE LOWER ELEVATIONS AND LOW TO MID 30S FOR THE HIGHER
TERRAIN. WINDS WILL ALSO PICK UP QUITE A BIT WED AFTERNOON...HOWEVER
THEY SHOULD REMAIN BELOW ADVISORY CRITERIA.
ON THURSDAY...TEMPS WILL BE COLD LATE WED/EARLY THURS BUT HAVE BEEN
INCREASED A FEW DEGREES COMPARED TO THE PREVIOUS FCST. MINS IN THE
TEENS ARE EXPECTED OVER MUCH OF THE HIGHER TERRAIN...WHILE VALUES IN
THE MID TO LOW 20S ARE LIKELY ACROSS THE PIEDMONT AND FOOTHILLS. IN
THE WAKE OF THE FROPA...DRIER HIGH PRESSURE CENTERED OVER THE GULF OF MEX
WILL BRIEFLY SPREAD OVER THE REGION FROM THE WEST. SOME LINGERING NW
FLOW SNOW SHOWERS WILL BE THE MAIN CONCERN FOR THE CWFA...AND SHOULD
TAPER OFF BY 12Z OR SO. HIGH TEMPS WILL REMAIN 1 TO 2 CATEGORIES
BELOW CLIMO FOR MID JAN WITH LOWS OVERNIGHT WARMING AT LEAST A
CATEGORY AS THICKNESSES BEGIN TO REBOUND AS WE MOVE INTO FRI.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 220 PM EST MONDAY...THE EXTENDED RANGE STARTS WITH A HIGH
AMPLITUDE RIDGE OVER THE WEST COAST AND BRITISH COLUMBIA. WPC
COMMENTED THAT THEY FAVOR SLOWER AND HIGHER AMPLITUDE DOWNSTREAM
TROUGHING WITH THIS PATTERN...THOUGH FOR THE MOST PART THEY
APPEAR TO HAVE GONE WITH A SERIES OF ENSEMBLE BLENDS FOR THE
EXTENDED RANGE. THE 12 UTC OPERATIONAL ECMWF IS NOW QUITE A BIT
SLOWER AND DEEPER THAN THE 12 UTC GFS WITH ENERGY DROPPING INTO THE
LONG WAVE FRIDAY AND FRIDAY NIGHT. AS A RESULT THE ECMWF BRINGS A
SHOT OF STRONG Q-VECTOR CONVERGENCE ACROSS THE FA...INDUCING SFC
CYCLOGENESIS OVER WRN NC FRIDAY EVENING. THIS IN TURN BRINGS PCPN
ACROSS MOST OF THE FA...ESPECIALLY THE NC ZONES. THE GFS IS SO MUCH
FARTHER EAST THAT MOST OF IT/S PCPN RESULTS FROM NW FLOW SNOW. I/M
NOT GOING TO JUMP ON THE NEW ECMWF SOLUTION JUST YET CONSIDERING HOW
MUCH DRIER THE GFS IS. HOWEVER...THE ECMWF QPF WOULD IMPLY THE
POTENTIAL FOR SEVERAL INCHES OF SNOW OVER PARTS OF THE NC
MOUNTAINS...WITH LIGHTER AMOUNTS TO THE EAST LATE FRIDAY. I/LL ADD A
TAG FOR MODERATE SNOW ACCUMULATIONS OVER THE NC MTNS TO THE HWO FOR
FRIDAY TO ACCOUNT FOR THIS.
FAIR AND COLD WEATHER WILL FOLLOW FOR SATURDAY AND SUNDAY...WITH
MODERATING TEMPERATURES AND CONTINUED DRY CONDITIONS NEXT MONDAY.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AT KCLT...A MIXTURE OF VFR/MVFR/IFR AND PERHAPS EVEN LIFR AT
CHARLOTTE THIS EVENING AS MOISTURE ASSOCIATED WITH APPROACHING
FRONTAL BOUNDARY PASSES THROUGH THE REGION. INITIALIZED TAF WITH
LOW END VFR CIGS KEEPING -RA DUE TO WIDESPREAD NATURE OF SHOWER
ACTIVITY ACROSS THE PIEDMONT. PER LATEST NEAR TERM GUIDANCE...CIGS
ARE EXPECTED TO LOWER TO MVFR LEVELS IN THE NEXT FEW HOURS AS THE
BOUNDARY LAYER CONTINUES TO SATURATE FURTHER. AROUND THE 10Z
TIMEFRAME...GUIDANCE AGAIN INDICATES FURTHER DETERIORATION OF CIGS
TO IFR LEVELS AS THE HEAVIER RA MOVES OUT ALLOWING THE NEAR SURFACE
LAYERS TO SETTLE/CONDENSE. THUS...PREVAILED -SHRA WITH AN MVFR VISB
AND AN IFR CIG AT 008FT WITH BR. FURTHERMORE...PREVIOUS TAF HAD
PROB30 FOR LIFR CONDITIONS DEVELOPING FOR ABOUT A 3-4 HOUR WINDOW IN
THE MORNING. HAD TO MAKE A DECISION ON THIS AND SINCE CONFIDENCE IS
ABOUT 50/50 WENT WITH A TEMPO FOR 3SM VISB AND 003FT LIFR CIG.
CONDITIONS WILL IMPROVE SLOWLY THROUGH THE MORNING WITH CIGS LIFTING
TO MVFR AROUND THE 16Z TIMEFRAME AND REACHING SOLID VFR BY AROUND
18Z. WINDS OVERNIGHT WILL REMAIN LIGHT AND SOUTHERLY WITH
INCREASING FLOW BY LATE MORNING WHERE WINDS VEER TO THE NW AROUND
8-10KTS WITH 15-18KT GUSTS POSSIBLE. ONE ADDITIONAL NOTE...HAD TO
LEAVE OFF DUE TO LINE RESTRAINTS...BUT WOULD LIKE TO ADD THAT WINDS
WILL BACK SOUTHERLY YET AGAIN AHEAD OF THE NEXT APPROACHING WAVE
LATE IN THE PERIOD.
ELSEWHERE...VFR/MVFR/IFR TO POSSIBLE LIFR CONDITIONS WILL PREVAIL
THROUGH THE OVERNIGHT HOURS OF THIS TAF PERIOD AS SHOWERS CONTINUE
TO PUSH THROUGH THE REGION KEEPING THE BOUNDARY LAYER SATURATED.
CIGS WILL CONTINUE TO DETERIORATE THROUGH THE MID MORNING HOURS AS
THE HEAVIEST PRECIPITATION PUSHES EAST ALLOWING FOR SCATTERED
-SHRA. IN RESPONSE...THE LOWEST LEVELS WILL LIKELY SETTLE SOMEWHAT
AND REMAIN SATURATED. THEREFORE...BROUGHT ALL SITES DOWN TO IFR BY
AROUND DAYBREAK WITH A 4HR TEMPO AT EACH SITE FOR POSSIBLE LIFR CIG
RESTRICTIONS. FOG WILL ALSO PRESENT AN ISSUE OVERNIGHT AMIDST THE
-SHRA THUS ADDED MENTION OF REDUCED VISB AT ALL SITES. CONDITIONS
WILL SLOWLY IMPROVE AT ALL SITES THROUGH THE LATE MORNING FROM WEST
TO EAST ACROSS THE REGION WITH VFR PREVAILING BY AROUND NOON. LIGHT
AND VARIABLE WINDS WILL INCREASE BY THE MORNING HOURS AT ALL SITES
AND WILL PREVAIL FROM THE NW THROUGH MUCH OF THE DAY BEFORE
GRADUALLY BACKING AHEAD OF THE NEXT APPROACHING WAVE NEAR THE END OF
THIS TAF CYCLE.
OUTLOOK...A COLD FRONT WILL PASS THROUGH THE REGION TUESDAY NIGHT.
FLIGHT RESTRICTIONS ARE POSSIBLE TUESDAY NIGHT INTO EARLY WEDNESDAY
OVER SOME OF THE AREA WITH THIS NEXT FRONT. YET ANOTHER FRONT MAY
ONCE AGAIN BRING PRECIP AND RESTRICTIONS TO THE MTNS FRIDAY.
CONFIDENCE TABLE...
06-12Z 12-18Z 18-24Z 00-06Z
KCLT HIGH 88% HIGH 84% HIGH 100% HIGH 100%
KGSP MED 73% MED 68% HIGH 100% HIGH 100%
KAVL LOW 58% HIGH 81% HIGH 100% HIGH 100%
KHKY HIGH 81% MED 65% HIGH 100% HIGH 100%
KGMU HIGH 80% MED 74% HIGH 100% HIGH 100%
KAND HIGH 87% MED 76% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JOH
NEAR TERM...ARK/CDG/WIMBERLEY
SHORT TERM...JPT
LONG TERM...MCAVOY
AVIATION...CDG
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1027 PM CST MON JAN 13 2014
.UPDATE...
ISSUED AT 708 PM CST MON JAN 13 2014
SOME CHANGES TO TONIGHT/S FORECAST BASED UPON CURRENT RADAR TRENDS
AND RAP/HRRR DEPICTION. AS NOTED BELOW...THE LOW LEVEL
FRONTOGENESIS AND WARM ADVECTION HAS PRIMARILY SHIFTED INTO THE
MINNESOTA RIVER VALLEY. WITH THE 900 MB FRONTOGENESIS BETWEEN THE
BUFFALO RIDGE AND MINNESOTA RIVER...SOME LIGHTS NOW COULD STILL
DEVELOP THIS EVENING IN SOUTHWEST MINNESOTA BUT BETTER CHANCE
REMAINS TO THE NORTHEAST. INSTEAD...LOOKING AT THE MAIN FORCING
FOR PRECIPITATION TO BE ASSOCIATED WITH THE UPPER LEVEL WAVE
MOVING SOUTHEAST ACROSS SD INTO IOWA. EXPECT A BAND OF
PRECIPITATION...SOMEWHAT CONVECTIVE IN NATURE...TO CONTINUE TO
ORGANIZE OVER CENTRAL SD THROUGH 03Z AND THEN MOVE SOUTHEAST
ACROSS THE AREA BETWEEN 03Z AND 09Z. TO THE NORTH OF THE VORTICITY
MAXIMUM...AM EXPECTING THAT A DEFORMATION ZONE WITH LIGHT
PRECIPITATION WILL SET UP PRIMARILY ACROSS SOUTHWEST MINNESOTA.
PRECIPITATION RATES WILL BE LIGHT AND...EXCEPT IN SW MN WHERE
DURATION MAY BE FOR A FEW HOURS...THE SPEED OF THE SYSTEM WILL
KEEP AMOUNTS TO A FEW HUNDREDTHS OF AN INCH.
AS FOR PRECIPITATION TYPE...THAT IS A LITTLE MORE DIFFICULT.
CURRENTLY FORECASTING THE PTYPE WILL BE DRIVEN BY SURFACE
TEMPERATURES. IN OTHER WORDS WHERE TEMPERATURES ARE ABOVE FREEZING
IT WILL EITHER BE RAIN OR RAIN AND SNOW WHILE WHERE IT IS AT OR
BELOW FREEZING IT WILL BE ALL SNOW. WITH ALL MODELS SHOWING 925 MB
TEMPS ABOVE FREEZING MUCH OF THE NIGHT...EXPECT THAT AS
PRECIPITATION STARTS AND WINDS INCREASE OUT OF THE WEST...MOST
AREAS WILL BE AT OR ABOVE FREEZING AND MOST PRECIPITATION WILL BE RAIN.
AS THE NIGHT PROGRESSES AND COLD AIR MOVES SOUTH...TEMPERATURES
WILL FALL BELOW FREEZING AND CHANGE IT TO SNOW. FOR THE MISSOURI
RIVER VALLEY...THE COLD AIR WILL PROBABLY LAG FAR ENOUGH BEHIND
THE PRECIPITATION TO KEEP IT ALL RAIN. IN SW MN...PRECIPITATION
WILL BE MORE SNOW ALTHOUGH IT WILL LIKELY START AS A MIX.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 417 PM CST MON JAN 13 2014
CHALLENGING FORECAST THIS EVENING AS MODELS HAVING A PRETTY
DIFFICULT TIME DETERMINING PRECIPITATION THREAT TONIGHT. FOR NOW
WILL LEAN TOWARDS THE ECMWF AND GFS OUTPUT WHICH CORRELATES MORE TO
THE PREVIOUS FORECASTS. MAIN REASONS ARE THAT THE LOW LEVEL WARM
ADVECTION IS ALREADY NORTH OF THE CWA AND WILL LIKELY REMAIN SO...SO
THE CHANCES FOR PRECIPITATION THIS EVENING WEIGH HEAVILY UPON
GETTING ANYTHING TO DEVELOP AS A VORTICITY LOBE MOVES FROM THE
WESTERN DAKOTAS INTO CENTRAL SD THIS EVENING. NOT BANKING ON MUCH
FROM THIS...ALTHOUGH THE NAM AND RAP ARE PRETTY EXCITED ABOUT
PRECIPITATION PRODUCTION WITHIN THIS LOCATION. WITH LITTLE OR NO LOW
AND MID LEVEL THERMAL GRADIENT AND A FAIRLY DRY LOWER LAYER
PRECIPITATION PRODUCTION SHOULD BE PRETTY DIFFICULT TO COME BY. HAVE
BACKED OFF ON POPS WEST OF INTERSTATE 29 THIS AFTERNOON AND EVENING
AND LOWERED SNOWFALL AMOUNTS EVERYWHERE. THE LOW LEVEL THERMAL
GRADIENT IS FARTHER NORTH AND EAST THAN PREVIOUSLY EXPECTED WHICH
HAS ALLOWED THE WARM ADVECTIVE PRECIPITATION TO DEVELOP FARTHER
NORTHEAST....WHICH IS RIGHT ON THE 925MB FRONT AND ALREADY MOVING
INTO WESTERN MINNESOTA. SO...HAVE MOVED THE START TIME OF THE
ADVISORY TO 6Z WHICH CORRELATES MORE TO THE INCREASE IN NORTHWEST
WINDS WHICH IF WE HAVE ANY SNOW ON THE GROUND WOULD START TO BLOW
AROUND.
TEMPERATURES STEADY TO FALLING ON TUESDAY WITH VERY STRONG WINDS.
THE WIND ADVISORY FOR THE AREA LOOKS SOLID AND EXPECT GUSTS TO 45
TO 50 MPH AT TIMES...ESPECIALLY IN THE MORNING.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 417 PM CST MON JAN 13 2014
WINDS SHOULD BE ON THE QUICK DOWNTREND ON TUESDAY NIGHT WITH A
WEDGE OF CLEARING WORKING ACROSS THE AREA WITH THE HIGH PRESSURE
RIDGE AXIS MOVING ACROSS. WINDOW FOR TEMPS TO DROP FAIRLY COOL
WITH 925 HPA COLD PUSH -12 TO -16C IN THE EASTERN HALF. SOME LOWS
DOWN CLOSER TO ZERO NEAR AND ADVANCE OF RIDGE AXIS...BUT SOME
LINGERING GRADIENT IN THE FAR EAST MAY HAVE SOMETHING TO SAY ABOUT
THAT...ESPECIALLY IF SHORT TERM SNOWFALL CONTINUES TO LOOK
DISAPPOINTING IN TERMS OF AMOUNTS.
STRONG WAVE WILL START TO MOVE INTO AREAS NEAR THE NORTHERN
PLAINS/CANADIAN BORDER BY WEDNESDAY EVENING. GANGLY WARM FRONT
EXTENDING SOUTHWARD WILL TRUDGE EASTWARD ACROSS THE CWA...WITH
A CONSENSUS OF NEAR THE I29 CORRIDOR BY 00Z THU. AHEAD OF THE
FRONT WILL DEVELOP A STOUT SOUTH TO SOUTHWEST FLOW...WITH A
WESTERLY PUSH OF WARMER AIR TO THE WEST OF THE FRONT. NOW LOOKING
LIKE THERE WILL BE ENOUGH NET LIFT WITHIN THE WARM FRONTAL ZONE
TO WARRANT A CHANCE LEVEL MENTION FOR LIGHT SNOW EVOLVING AS
BOUNDARY WORKS EASTWARD ACROSS THE CWA...MAINLY ACROSS THE NORTH
WHERE SOME BETTER SUPPORT TO DEEPER DIV Q. SHOULD BE A FAIR AMOUNT
OF CLOUDS EARLY ON...BUT SOME CLEARING WORKING IN FROM THE WEST
LATER IN THE DAY...OR AT A MINIMUM A THINNING TO HIGHER LEVEL
CLOUDS. ONE SHORTCOMING THAT LOOKED TO BE A FACTOR IN THE MODELS
WAS ALLOWING TEMPS TO WARM ENOUGH IN THE WARM SECTOR...AND RAISED
TEMPS OVER GUIDANCE ONCE AGAIN IN THE WEST...BACK CLOSER TO WHERE
PREVIOUS FORECAST RESIDED.
STILL LOOKING TO THE WIND THREAT THURSDAY AS THE MOST SIGNIFICANT
ISSUE IN THE FORECAST PERIOD. SOMEWHAT LOW CONFIDENCE IN TIMING OF
THE ABSOLUTE STRONGEST WINDS TIED TO WHEN LARGEST LOW LEVEL
ISENTROPIC SUPPORT FOR SUBSIDENCE WILL INITIATE...WITH UP TO 12H
DIFFERENCE BRACKETING SOLUTIONS OF NAM /SLOWEST/ TO GFS /FASTEST/.
AT THIS POINT...MAY SEE A LITTLE PARTIAL DECOUPLING IN THE WARM
SECTOR OVERNIGHT WHEN LIKELY TO GET SOME CONTINUED RISING TEMPS IN
THE EAST FOR A WHILE INTO THE NIGHT. MAY LIMIT SPEED POTENTIAL A
BIT...ESPECIALLY AT LOWER ELEVATIONS...BUT WILL NOT TAKE LONG TO
GET COUPLING TO KICK IN THOUGH WITH COLD AIR ADVECTION STARTING
AFTER 06Z. THIS SHOULD ALSO HELP TO KEEP TEMPS UP ABOVE GUIDANCE
WITH MIXING OF +2 TO -2 925 HPA TEMPS EXPECTED THROUGH 12Z. WITH
45 TO 55 KNOTS IN THE MID TO UPPER MIXED LAYER...WOULD PUT
PROSPECT OF NEEDING A HIGH WIND WATCH TO BE QUITE HIGH. FOR
NOW...WILL WORK THROUGH CURRENT WIND HIGHLIGHTS FIRST BEFORE
COMPLICATING MATTERS WITH THE NEXT...BUT CONTINUE TO HIT MENTION
HARD IN WEATHER STORY/HWO/SOCIAL MEDIA.
HAVE PUSHED MENTION TO LIGHT SNOW UP TOWARD LOWER LIKELY POPS IN
THE NORTHEAST HALF OF THE AREA AND TRIED TO TIME WITH AN EC/18Z
GFS CONSENSUS...WHICH HAS BEEN TREND IN MAJORITY SOLUTIONS TODAY.
WILL HAVE TO WATCH VISIBILITY ISSUES AS WELL...AS WILL BE QUITE
LOW AT TIMES OF ANY FALLING SNOW...BUT NOT SURE THERE WILL BE
ENOUGH SNOW FROM EARLIER TO MAKE WIDESPREAD BLOWING SNOW A LARGE
ENOUGH THREAT. DID CONTINUE MENTION OF SOME PATCHY OF BLOWING
SNOW. OTHER CONCERN WILL BE TEMPS STARTING TO FALL DURING THE
DAY... WHICH BY EVENING WITH THE STRONG WINDS WILL PRODUCE SOME
-20 TO -25 WIND CHILLS IN AT LEAST THE NORTHEASTERN HALF OF THE
AREA. COLD AIR DIGS INTO THE EASTERN AREAS ON FRIDAY...AND WILL GO
WITH HIGHS IN THE TEENS EAST TO LOWER 30S WEST AS ANOTHER RIDGE
AXIS DRIFTS ACROSS THE AREA.
LITTLE TO HANG ONES HAT ON AS FAR AS TIMING OR LOCATION OF
FEATURES IN THE SATURDAY TO MONDAY TIME FRAME. SHOULD TO CONTINUE
TO SEE A CLIPPERY NORTHWEST FLOW...BUT WITH RIDGE AXIS NUDGING
EAST...THE SIGNIFICANT PRECIPITATION THROUGH SHOULD REMAIN
NORTHEAST OF THE AREA...AND WILL BE LEFT TO A CHASE OF THE
POTENTIAL NON DIURNAL TEMPERATURE TRENDS. ONE PERIOD TO WATCH FOR
POSSIBLE LIGHT PRECIPITATION WOULD BE LATER FRIDAY NIGHT AND
SATURDAY... AND WITH STRONGER WARM AIR ADVECTION IN TYPES OF
SYSTEM... WOULD OPEN THE DOOR FOR SOME MIXED TYPE PRECIPITATION IF
SUCH A SOLUTION WOULD EVOLVE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1026 PM CST MON JAN 13 2014
FOR AVIATION INTERESTS...IT APPEARS THE WORST CONDITIONS WILL BE
OVER SW MN...WHERE SNOW AND BLOWING SNOW COULD PRODUCE BRIEF
PERIODS OF IFR CONDITIONS BETWEEN MIDNIGHT AND DAWN.
OTHERWISE...FOR TAF LOCATIONS...THERE MAY BE SOME LIGHT SNOW OR
RAIN OVER NIGHT AT KFSD AND KHON BUT ANY PCPN WILL BE FAIRLY
SCATTERED AND THE DURATION WILL BE RELATIVELY SHORT SUCH THAT DID
NOT INCLUDE IN TAFS AT THIS TIME. HOWEVER...SATELLITE AND
OBSERVATIONS SHOWING 2000 TO 3000 FT CIGS OVER CENTRAL ND INTO
NORTH CENTRAL SD AND TRAJECTORIES BRING THESE CLOUDS TO KHON
AROUND 06Z AND KFSD AROUND 08Z. STRONG FLOW AND SOME MIXING WILL
HELP TO ADVECT CLOUDS EAST AND SLOWLY RAISE CIGS TUESDAY MORNING
SO THAT EXPECTING VFR CONDITIONS TO RETURN LATE IN THE MORNING.
WINDS EXPECTED TO ALSO INCREASE AFTER 06Z WITH GUSTS BETWEEN 30
AND 40 KTS EXPECTED THE REMAINDER OF TONIGHT THROUGH LATE TUESDAY
AFTERNOON. WINDS WILL ONLY SLOWLY DECREASE AFTER SUNSET.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY UNTIL 5 PM CST TUESDAY FOR SDZ038-039-050-052>071.
WINTER WEATHER ADVISORY UNTIL 3 PM CST TUESDAY FOR SDZ040.
MN...WIND ADVISORY UNTIL 5 PM CST TUESDAY FOR MNZ098.
WINTER WEATHER ADVISORY UNTIL 3 PM CST TUESDAY FOR MNZ071-072-
080-081-089-090-097.
IA...WIND ADVISORY UNTIL 5 PM CST TUESDAY FOR IAZ001>003-012>014-
020>022-031-032.
NE...WIND ADVISORY UNTIL 5 PM CST TUESDAY FOR NEZ013-014.
&&
$$
UPDATE...SCHUMACHER
SHORT TERM...08
LONG TERM...CHAPMAN
AVIATION...SCHUMACHER
AREA FORECAST DISCUSSION
NWS SPOKANE WA
950 PM PST Mon Jan 13 2014
.SYNOPSIS...
One last evening of breezy winds and lingering mountain
snow/valley rain showers today before a much quieter weather
pattern develops over the Inland Northwest. A ridge of high
pressure will develop on Tuesday, with dry weather persisting into
the weekend.
&&
.DISCUSSION...
Evening update: Minor update to the forecast to adjust winds and
lower Pops/QPF. Winds are decreasing this evening as cross CWA
pressure gradients rapidly diminish from near 20mb this afternoon
toward 9mb as of 8PM. There are still a few isolated windy spots
in the East Slopes of the Cascades which could be dealing with
somewhat of a mountain wave given the sharp inversion noted on the
KUIL sounding and NAM forecast cross section through the Cascades.
Entiat RAWS was blowing around 30 mph with gusts to 45 mph with
subtle weakening this last hour. Further north, the Aeneas and
Leecher RAWS were also gusting into the 55 mph range but each have
since diminished considerably.
Northwest flow into the ID Panhandle and Cascade Crest continues
to bring scattered light showers with spotty 0.01" here and there.
Most cams suggest this is mainly in the form of flurries which
is supported by the lack of moisture in the dendritic layer.
Consequently, Pops have been reduced but weren`t very high to
start with. /sb
&&
.AVIATION...
06Z TAFS: Main aviation impacts through 23z will be incr threat for
stratus along the WA/ID border then spreading west toward Moses
Lake. Models are overdoing the boundary layer moisture at this hour
so delayed the timing of stratus and also raised cigs frm previous
fcst based on obs vcnty KCOE. High Res HRRR does not support
restrictions anywhere in the forecast area but BUFKIT/MOS do and
opted to keep fcst trends this direction as winds decr near 10kts
and swing arnd to the S/SE. Following a short break in the stratus
Tue aftn...areas of low clouds and fg will return arnd 06z Wed. /sb
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 32 43 27 40 25 37 / 0 0 0 0 0 0
Coeur d`Alene 32 43 26 42 25 38 / 0 10 0 0 0 0
Pullman 34 47 30 44 30 44 / 0 0 0 0 0 0
Lewiston 34 50 29 47 29 46 / 0 0 0 0 0 0
Colville 31 39 29 37 22 35 / 0 10 0 0 0 0
Sandpoint 33 39 29 39 24 36 / 10 10 10 10 10 0
Kellogg 33 40 29 39 28 38 / 10 10 0 0 0 0
Moses Lake 34 46 24 44 22 38 / 0 0 0 0 0 0
Wenatchee 30 44 25 43 24 37 / 0 0 0 0 0 0
Omak 28 39 23 37 21 36 / 0 0 0 0 0 0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS NEW YORK NY
959 AM EST TUE JAN 14 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE EAST OF THE TRI-STATE AREA BY THIS
EVENING. A WAVE OF LOW PRESSURE WILL DEVELOP ON THE FRONT JUST OFF
THE MID ATLANTIC COAST LATER TODAY AND PASS EAST OF LONG ISLAND
THIS EVENING. WEAK HIGH PRESSURE BRIEFLY BUILDS IN BEHIND THE
SYSTEM TONIGHT AND WEDNESDAY. MULTIPLE LOWS IMPACT THE NORTHEAST
THE SECOND HALF OF THE WEEK THROUGH THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
REGION CURRENTLY IN...AND FORECAST TO BE UNDER RIGHT REAR QUADRANT
OF 170+ KT 250 HPA JET ALL DAY. BASED ON THIS FORCING...AND
MULTIPLE SHORTWAVES EVIDENT UPSTREAM IN WATER VAPOR HAVE CONTINUED
WITH CATEGORICAL POPS FOR REMAINDER OF DAY. COULD SEE SOME LULLS
IN BETWEEN SHORTWAVES...SO WENT WITH PERIODS OF RAIN. WHILE SOME
PATCHY FOG IS POSSIBLE...EXPECT ANY VISIBILITIES TO GENERALLY BE
AT OR ABOVE 3 MILES...SO HAVE REMOVED THE PATCHY FOG FROM THE
FORECAST.
GIVEN CLOUD COVER AND PRECIPITATION...DO NOT EXPECT MUCH MOVEMENT
IN TEMPERATURE TODAY...SO HAVE UPDATED BASED UPON BLEND OF
LAV/MET/MAV GUIDANCE WITH NAM AND HRRR 2-METER TEMPERATURES WHICH
REFLECT THIS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
FRONT IS EXPECTED TO CLEAR THE AREA EARLY THIS EVE...ALTHOUGH
THERE IS NO STRONG PUSH OF COLD AIR BEHIND IT SO CLEARING WILL BE
SLOW. THE LOW TRACKS INTO THE GULF OF MAINE THIS EVE AND THEN
CONTINUES THROUGH THE CANADIAN MARITIMES TONIGHT WITH WEAK RIDGING
BUILDING INTO THE REGION WED NIGHT.
EXPECT A CHILLY NIGHT WITH LIGHT WINDS AND MOSTLY CLEAR SKIES. NAM
MOISTURE PROFILES LOOK OVERDONE TONIGHT...ALTHOUGH THERE COULD BE
SOME PATCHY FOG AT OUTLYING LOCATIONS. LOWS IN THE MID TO UPPER
20S INLAND TO MID TO UPPER 30S IN METRO NY/NJ.
AS ONE PIECE OF UPPER ENERGY LIFTS OUT ANOTHER WILL DIVE THROUGH
THE PLAINS AND MIDWEST RE-AMPLIFYING THE UPPER TROUGH. AT THE
SFC...WEAK LOW PRES WILL TRACK THROUGH THE GREAT LAKES INTO SE
CANADA ON WED WITH A WEAK COLD FRONT APPROACHING THE AREA. DRY
WEATHER SHOULD HOLD THROUGH THE DAY.
HIGHS ON WED ARE TRICKY AS THE NAM WANTS TO DEVELOP STRATUS ON A
S-SE FLOW...WHILE THE GFS IS NOT AS PESSIMISTIC WITH A SW FLOW.
HAVE LEANED TOWARDS THE MORE OPTIMISTIC AND WARMER GFS FOR THE
TIME BEING.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
UNCERTAINTY REMAINS IN THE EXTENDED PERIOD WITH THE MODELS HANDLING
OF THE EVOLUTION OF MULTIPLE LOW PRESSURE SYSTEMS. PERIOD STARTS
OFF AND GENERALLY REMAINS UNDER A AMPLIFYING TROUGH...RESULTING IN A
EXTENDED THREAT OF UNSETTLED WEATHER WITH AN ABUNDANCE OF COASTAL
LOW FORMATIONS. COLD FRONT APPROACHES AND PASSES THROUGH THE REGION
LATE WED. FIRST ISSUE AT HAND IS A DEVELOPING COASTAL LOW WED NIGHT
INTO THURSDAY...WITH THE 00Z GFS BEING THE OUTLIER ON THE PLACEMENT
AND STRENGTH. GENERAL CONSENSUS WOULD LEND WITH THE LOW FORMING OFF
THE CAROLINA COAST BY THURS MORNING AS A POTENT SHORTWAVE ROUNDS THE
BASE OF THE TROUGH AND PUSHES OFFSHORE. THE LOW TREKS TO THE
NORTHEAST THURSDAY...PASSING EAST OF THE 40/70 BENCHMARK AROUND 00Z
FRI. 00Z NAM/CMC DEVELOP A MUCH DEEPER LOW...WITH THE GFS AND ECMWF
BOTH SHOWING THE ASSOCIATED UPPER LEVEL ENERGY WEAKENING DURING THE
DAY. AS SUCH...SOME QUESTION AS TO HOW FAR WEST THE PRECIPITATION
PUSHES THURS. WENT AHEAD AND CONTINUE SLIGHT CHANCE POPS LATE WED
NIGHT...THEN MAINTAINING SLIGHT CHANCE OVER WESTERN AREAS...AND
CHANCE POPS EASTERN LONG ISLAND AND INTO CT. LATEST MODEL RUNS DO
SUGGEST THE DEVELOPMENT OF AN INVERTED TROUGH ALONG THE
LOW...WHICH COULD INCREASE THE COVERAGE OF THE PRECIPITATION
FURTHER WEST. PRECIPITATION SHOULD THEN TAPER OFF WEST TO EAST BY
THURS NIGHT.
DRY WEATHER IN PLACE LATE THURS THROUGH FRIDAY AS THE REGION SITS
BETWEEN THE DEPARTING LOW AND THE NEXT APPROACHING LOW MOVING
THROUGH THE GREAT LAKES AS WEAK HIGH PRESSURE ATTEMPTS TO NUDGE IN.
THE LATTER LOW WILL PLAY THE PART IN BRINGING THE NEXT CHANCE OF
PRECIPITATION FRI NIGHT THROUGH SATURDAY AS IT DRAGS A COLD FRONT
THROUGH THE REGION. AS THE FRONT PUSHES OFFSHORE...ONCE AGAIN THE
MODELS DEVELOP A COASTAL LOW ALONG THE FRONT WITH THE FIRST
SHORTWAVE ENERGY FRI NIGHT. AS A SECOND...STRONGER SHORTWAVE
ROUNDS THE TROUGH...EXPECTING A MUCH DEEPER DEVELOPMENT OF THE
COASTAL LOW SAT-SAT NIGHT THAN WAS SEEN WITH THE COASTAL LOW
EARLIER IN THE WEEK. GFS...AS IT TENDS TO BE...IS MORE PROGRESSIVE
IN MOVING THE LOW TO THE NORTHEAST...THUS ALLOWING FOR MOST OF ITS
DEEPENING TO OCCUR TO THE NORTH OF THE AREA...WITH MINIMAL IMPACT.
ECMWF AND CMC LAG A BIT MORE...SUGGESTING THE PRECIPITATION WILL
LINGER INTO SAT EVENING. FOR NOW...WILL CAP WITH CHANCE
POPS...THOUGH THIS IS INCREASING CONFIDENCE OF SEEING
PRECIPITATION SAT...WITH THE TIMING THE UNKNOWN FACTOR.
THE PASSING OF ANOTHER SHORTWAVE AND SURFACE LOW COULD BRING ANOTHER
SHOT OF PRECIPITATION SUNDAY...WITH EVEN THEN ANOTHER CLIPPER
POSSIBLE MONDAY. HOWEVER...THERE IS SOME SUGGESTION OF A MORE
ZONAL FLOW BY MONDAY THAT COULD KEEP THE MAIN ENERGY/FORCING TO
THE NORTH...AND THUS KEEP ANY PRECIPITATION TO THE NORTH.
TEMPS GENERALLY ABOVE NORMAL FOR THE SECOND HALF OF THE WEEK. THE
COLD FRONT THIS WEEKEND SHOULD FINALLY USHER IN A MUCH COLDER
AIRMASS AS THE TROUGH ALOFT DEEPENS. TEMPS THEN HOVER NEAR NORMAL
THROUGH THE WEEKEND INTO NEXT WEEK. SIDED WITH A BLEND OF ECE/WPC
FOR TEMPS THROUGH THE EXTENDED.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
A COLD FRONT MOVES ACROSS THE AREA LATE THIS AFTERNOON INTO EARLY
THIS EVENING. VFR DETERIORATES TO MVFR/IFR/LIFR AHEAD OF IT WITH
STRATUS...FOG...AND RAIN MOVING IN ESPECIALLY IN THE TIME FRAME OF
MID MORNING THROUGH MID AFTERNOON...GENERALLY AROUND 15Z-22Z.
EXPECT SOME VARIABILITY AND FLUCTUATION OF CATEGORIES WITHIN THE
TIME FRAME FROM SITE TO SITE WITH AMENDMENTS LIKELY TO BETTER
REFINE TIMING OF THESE LOWER CONDITIONS.
CONDITIONS SHOULD IMPROVE SLIGHTLY TO MVFR LATE AFTERNOON AND
EVENING AS RAIN EVENTUALLY ENDS FROM WEST TO EAST. STRATUS SHOULD
SCATTER...WITH FOG LINGERING DUE TO LIGHT WINDS AND LINGERING
MOISTURE. WINDS GENERALLY 10 KTS OR LESS THROUGH THE PERIOD WITH
DIRECTION S-SW BECOMING W-NW TONIGHT BEHIND THE COLD FRONT. WINDS
BECOME LIGHTER AND VARIABLE IN DIRECTION LATE...TAKING A MORE
ONSHORE DIRECTION BY WED MORNING. BECAUSE OF THIS...THERE WILL BE
THE POTENTIAL FOR PATCHY FOG WITH MVFR CONDITIONS POSSIBLE.
OVERALL...CONFIDENCE IS HIGH WITH WIND SPEED FORECAST AND MODERATE
WITH THE WIND DIRECTION FORECAST. CONFIDENCE IS LOWER ON THE
CATEGORY FORECAST AS TIMING OF LOWERING CATEGORY COULD BE OFF BY
1-3 HOURS...LIKELY BEING LATER THAN FORECAST. IT IS POSSIBLE THAT
THE MINIMUM CATEGORIES TODAY COULD BE END UP BEING ONE LEVEL
HIGHER THAN FORECAST.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
KJFK FCSTER COMMENTS: AMENDMENTS LIKELY AS CONDITIONS COULD
FLUCTUATE TODAY. MVFR AND IFR MAY OCCUR 1-3 HRS LATER THAN
FORECAST.
KLGA FCSTER COMMENTS: AMENDMENTS LIKELY AS CONDITIONS COULD
FLUCTUATE TODAY. MVFR AND IFR MAY OCCUR 1-3 HRS LATER THAN
FORECAST.
KEWR FCSTER COMMENTS: AMENDMENTS LIKELY AS CONDITIONS COULD
FLUCTUATE TODAY. MVFR AND IFR MAY OCCUR 1-3 HRS LATER THAN
FORECAST.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: AMENDMENTS LIKELY AS CONDITIONS COULD
FLUCTUATE TODAY. MVFR AND IFR MAY OCCUR 1-3 HRS LATER THAN
FORECAST.
KHPN FCSTER COMMENTS: AMENDMENTS LIKELY AS CONDITIONS COULD
FLUCTUATE TODAY. IFR AND LIFR MAY OCCUR 1-3 HRS LATER THAN
FORECAST.
KISP FCSTER COMMENTS: AMENDMENTS LIKELY AS CONDITIONS COULD
FLUCTUATE TODAY. MVFR AND IFR MAY OCCUR 1-3 HRS LATER THAN
FORECAST.
OUTLOOK FOR 12Z WED THROUGH SAT...
.WED...POSSIBLE MVFR IN MORNING WITH PATCHY FOG...OTHERWISE VFR.
.WED NIGHT...SLIGHT CHANCE OF PRECIPITATION...WINTRY MIX N/W OF NYC
TERMINALS...RAIN ELSEWHERE. MVFR OR LOWER POSSIBLE.
.THU-THU EVE...PERIODS OF MVFR OR LOWER AND MIXED PRECIPITATION
POSSIBLE - TIMING UNCERTAIN.
.LATE THU NIGHT-FRI...MAINLY VFR.
.SAT...PERIODS OF SUB-VFR AND MIXED PRECIPITATION POSSIBLE - TIMING
UNCERTAIN. CHANCE W-NW GUSTS 25 KT.
&&
.MARINE...
SEAS AT 44017 DOWN TO 4.3 FT FOR PAST TWO HOURS...WITH WINDS
EXPECTED TO CONTINUE TO SLOWLY DIMINISH AND ONLY SEEING 1.6 FT OF
SWELL UPSTREAM AT 44066...AND WAVEWATCH RUNNING 1 TO 2 FT TOO
HIGH...HAVE CANCELLED THE SCA FOR ANZ-350. FOR NOW HAVE LEFT 5 FT
SEAS IN THE FORECAST FOR TONIGHT...BUT CONFIDENCE IN OCCURRENCE IS
ONLY AROUND 50 PERCENT. LIKELY WILL LOWER SEAS TO 4 FT WITH
AFTERNOON UPDATE.
GENERALLY EXPECTING SUB- SCA WINDS ON ALL WATERS THROUGH FRIDAY.
DEPENDING ON THE EXACT TRACK OF EACH COASTAL LOW AND WHERE IT
DEPENDS THE MOST...COULD SEE GUSTS UP TO AROUND 25 KTS ON THE
OCEAN WATERS FORM. THE COMBINATION OF COLD AIR ADVECTION AND A
TIGHTENING PRESSURE GRADIENT WITH THE PASSAGE OF THE COLD
FRONT...FOLLOWED BY THE COASTAL LOW SHOULD PRODUCE GUSTS TO AT
LEAST 25-30 KTS SAT INTO MON. GALES MAY BE POSSIBLE AS WELL SAT-
SUN ON THE OCEAN WATERS.
SEAS REMAIN ELEVATED THROUGH THE PERIOD...WITH AT LEAST 5 FT
EXPECTED ON THE OCEAN WATERS WED THROUGH THE WEEKEND. COULD SEE
SEAS BUILD 6-9 FT OVER THE WEEKEND AS WELL WITH THE INCREASING
WIND FLOW.
&&
.HYDROLOGY...
GENERALLY LOOKING AT 0.25 TO 0.50 INCHES OF RAINFALL ON TUE...BUT
PERHAPS AS MUCH AS AROUND 3/4 OF AN INCH ACROSS EASTERN LI/SE CT.
WHILE THIS WILL NOT GENERATE ANY FLOOD THREATS...THE POTENTIAL
STILL EXISTS FOR FLOODING DUE TO ICE JAMS. ANY OBSERVED OR
REPORTED ICE JAM DEVELOPMENT MAY WARRANT THE ISSUANCE OF A FLOOD
WARNING WITH LITTLE NOTICE.
&&
.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 FOR HAZARDOUS SEAS UNTIL 6 AM EST
WEDNESDAY FOR ANZ350.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL NOON EST TODAY
FOR ANZ353.
&&
$$
SYNOPSIS...24/SEARS
NEAR TERM...MALOIT
SHORT TERM...24
LONG TERM...SEARS
AVIATION...MPS
MARINE...MALOIT/24/SEARS
HYDROLOGY...MALOIT/24
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
540 AM EST TUE JAN 14 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH THE FORECAST AREA EARLY TODAY. WEAK
HIGH PRESSURE BEHIND THE FRONT WILL BE OVER THE AREA THIS EVENING.
A REINFORCING COLD FRONT WILL MOVE THROUGH THE AREA WEDNESDAY
AFTERNOON. LITTLE MOISTURE WILL BE ASSOCIATED WITH THIS FRONT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CONVERGENCE ALONG THE COLD FRONT PLUS LIFT ASSOCIATED WITH THE
RIGHT ENTRANCE REGION OF THE H25 JET WAS HELPING SUPPORT SHOWERS
THIS MORNING. RADAR TRENDS SHOW SHOWER COVERAGE HAS DIMINISHED BUT
THE SPC WRF AND HRRR SHOW COVERAGE INCREASING AGAIN LATER THIS
MORNING. THIS INCREASE APPEARS TO BE IN RESPONSE TO LIFT
ASSOCIATED WITH THE MAIN MID-LEVEL SHORTWAVE TROUGH AFFECTING THE
AREA. THE HIGH-RESOLUTION MODELS INDICATE SHOWERS ENDING FROM WEST
TO EAST FROM ABOUT 1100 AM TO 100 PM. DRYING BEHIND THE MID-
LEVEL SHORTWAVE TROUGH AND H85 COLD ADVECTION SHOULD BECOME
DOMINATE BEGINNING AROUND 100 PM ACCORDING TO THE NAM AND GFS. WE
WILL GET OFF TO A RELATIVELY WARM START BECAUSE OF CLOUDINESS AND
MIXING AHEAD OF THE COLD FRONT THIS MORNING. THE TEMPERATURE
GUIDANCE WITH HIGHS NEAR 60 NORTH TO MIDDLE 60S SOUTHEAST APPEARS
REASONABLE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
WEAK RIDGING WILL BE OVER THE FORECAST AREA THIS EVENING WITH THE
RIDGE FURTHER WEAKENING LATE TONIGHT AND WEDNESDAY AHEAD OF THE
NEXT COLD FRONT. THIS REINFORCING FRONT WILL MOVE THROUGH THE AREA
WEDNESDAY AFTERNOON AND EVENING. THE MODELS CONTINUE TO INDICATE
MOST OF THE MOISTURE WITH THIS SYSTEM WILL REMAIN NORTH AND EAST
OF THE FORECAST AREA. THE NAM AND GFS MOS SUPPORT POPS LESS THAN
20 PERCENT IN THE SOUTH AND CENTRAL PART TO 20 TO 50 PERCENT IN
THE NORTH PART WEDNESDAY AFTERNOON AND EVENING. THE GFS SHOWS THE
LEAST MOISTURE COMPARED TO THE NAM AND ECMWF. PLAN TO FORECAST
SLIGHT CHANCE POPS IN THE NORTH PART AS INDICATED BY THE GFS MOS.
THE HIGHER NAM MOS HAS NOT BEEN CONSISTENT. THERE IS A POSSIBILITY
THERE WILL BE ENOUGH COOLING FOR SNOW IN THE NORTH PART BUT WITH
MARGINAL TEMPERATURES AND MOISTURE THE CHANCE APPEARS LOW AT THIS
TIME. THE NAM... GFS...AND ECMWF INDICATE DRYING AND DOWNSLOPE FLOW
BY LATE WEDNESDAY NIGHT. THE TEMPERATURE GUIDANCE WAS CONSISTENT.
EXPECT LOWS MAINLY IN THE MIDDLE 30S TONIGHT WITH HIGHS IN THE
MIDDLE 50S TO NEAR 60 WEDNESDAY. THE WARM GUIDANCE TEMPERATURES
WEDNESDAY APPEAR REASONABLE BECAUSE OF WARMING THAT WILL OCCUR
JUST AHEAD OF THE COLD FRONT. IT WILL TURN MUCH COOLER BY LATE
WEDNESDAY NIGHT BEHIND THE FRONT WITH LOWS IN THE MIDDLE 20S TO
AROUND 30.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
THE MEDIUM-RANGE MODELS CONTINUE TO DISPLAY BELOW NORMAL
TEMPERATURES WITH AN UPPER-LEVEL TROUGH REMAINING OVER THE
EASTERN PART OF THE NATION. THE GFS AND ECMWF SHOW A COLD FRONT
FRIDAY WITH LITTLE MOISTURE. THE 00Z ECMWF INDICATED LESS MOISTURE
THAN PREVIOUS RUNS AND WAS IN BETTER AGREEMENT WITH THE GFS. WE
MAINTAINED THE DRY FORECAST ALTHOUGH THERE IS INCREASED FORECAST
UNCERTAINTY BECAUSE OF THE LACK OF MODEL RUN-TO-RUN CONSISTENCY.
EXPECT TEMPERATURES WILL REMAIN BELOW NORMAL AS INDICATED BY THE
GFS...ECMWF AND EKD MOS.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
PATCHY LIGHT RAIN CONTINUES ACROSS THE AREA AHEAD OF A COLD FRONT
NOW ENTERING THE TN VALLEY. EXPECT LIFR/IFR CONDITIONS TO PERSIST
AROUND 15Z-16Z TODAY. IN ADDITION...LLWS MAY BE A CONCERN UNTIL 15Z
AS WELL WITH SW WINDS AROUND 30 KTS AT 2 KFT. THREAT OF RAIN WILL
END WITH FRONTAL PASSAGE. AFTER FRONT PASSES LATE MORNING/EARLY
AFTERNOON...EXPECT A RETURN TO VFR WITH RISING CIGS. SKIES SHOULD
BECOME MOSTLY CLEAR BY 00Z WEDNESDAY AS WEAK HIGH PRESSURE BUILDS IN
FROM THE WEST.
EXTENDED AVIATION OUTLOOK...A SERIES OF DRY COLD FRONTS WILL MOVE
THROUGH DURING THE WEEK. LOW CONFIDENCE ON ANY PRECIP OR
RESTRICTIONS...BUT BREEZY CONDITIONS POSSIBLE AT TIMES.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAY ME
938 AM EST TUE JAN 14 2014
.SYNOPSIS...
A SERIES OF WEAK LOW PRESSURE SYSTEMS WILL TRACK NORTHEAST ALONG
THE EASTERN SEABOARD THIS WEEK. EACH OF THESE LOWS PROVIDE A ROUND
OF MAINLY LIGHT PRECIPITATION... AND EACH ONE WILL ALSO BRING
WAVES OF COLDER AIR. THE FIRST SYSTEM CROSSES THE REGION TODAY...
AND WILL BRING SOME SPOTTY FREEZING RAIN IN THE HILLS AND
MOUNTAINS... BEFORE CHANGING TO RAIN ON TUESDAY. ANOTHER SYSTEM
WILL BRUSH THE COAST OF NEW ENGLAND ON THURSDAY. WE WILL SEE
ANOTHER ONE DAY BREAK ON FRIDAY... BEFORE ANOTHER SYSTEM MOVES IN
FRIDAY NIGHT AND SATURDAY.... WHEN IT WILL LIKELY BE COLD ENOUGH
TO PRODUCE MAINLY SNOW.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
HAVE DROPPED FREEZING RAIN ADVISORIES FOR NORTHERN LOCATIONS.
MESONET DATA NOW SHOWING ALL COMMUNITIES ABOVE FREEZING AT THIS TIME.
PREV DISC...HAVE UPDATED GRIDS BASED ON CURRENT CONDITIONS. TEMPS HAVE
ALREADY WARMED TO THEIR HIGHS IN SOME LOCATIONS...BUT SHOULD LEVEL
OFF OVER THE NEXT COUPLE HOURS. THIS WILL ALLOW FOR AREAS OF
FREEZING RAIN...BUT THEY WILL BE LIMITED TO THE COLDEST SECTIONS
OF THE ADVISORY REGION. EXPECT PATCHY FOG TODAY.
LATEST HRRR RUN BRINGS THE BACK EDGE OF THE PRECIP OUT OF NH BY
AROUND 02Z. IN THE MEANTIME...PERIODS OF RAIN WILL CONTINUE
THROUGHOUT THE DAY.
PREV DISC...
RAIN NOW SLOWLY ARRIVING FROM THE WEST. TEMPERATURES
STILL AT OR BELOW FREEZING IN SPOTTY LOCATIONS IN THE HILLY AREAS
FROM CENTRAL NEW HAMPSHIRE NORTHEASTWARD INTO WEST CENTRAL MAINE.
STILL A THREAT FOR SOME LIGHT ICING THIS MORNING IN THESE AREAS.
SOUTHERN SOMERSET COUNTY... HOWEVER... HAS RISEN SAFELY ABOVE
FREEZING AND THUS FREEZING RAIN IS NO LONGER EXPECTED THERE. THE
ADVISORY HAS BEEN DROPPED FOR SOUTHERN SOMERSET COUNTY ONLY.
ORIGINAL DISCUSSION...
RAIN HAS BEEN SLOW TO MOVE INTO THE REGION OVERNIGHT... BUT IS
FINALLY SHOWING SIGNS OF REACHING THE WESTERN PART OF THE FORECAST
AREA EARLY THIS MORNING. TEMPERATURES ARE HIGHLY VARIABLE ACROSS
THE HILLS AND MOUNTAINS. SOME MESONET STATIONS ACROSS THIS AREA
ARE IN THE 40S... WHILE OTHER AREAS ARE NEAR OR BELOW FREEZING. AS
A RESULT... STILL EXPECT POCKETS OF FREEZING RAIN THROUGH THE
MORNING HOURS. THE VARIABLE TEMPERATURES MAY ACTUALLY MAKE IT MORE
DANGEROUS WHEN DRIVING AS IT MAKES IT MORE LIKELY TO RUN ACROSS
UNEXPECTED AREAS OF ICING. SOME PARTS OF MERRIMACK AND BELKNAP
COUNTY ARE BELOW FREEZING WITH RAIN SPREADING IN THIS MORNING. DID
NOT EXPAND THE ADVISORY FOR THESE AREAS AS THE POCKETS OF
SUBFREEZING TEMPERATURES ARE VERY LOCALIZED AND CAN BE HANDLED
WITH A SPECIAL WEATHER STATEMENT IF THEY DO NOT RISE BEFORE THE
RAIN ARRIVES. WILL CONTINUE TO MONITOR MESONET TEMPERATURE
READINGS THROUGH THE MORNING AND MAY BE ABLE TO CANCEL PARTS OF
THE ADVISORY EARLY AS TEMPERATURES WARM ABOVE FREEZING.
COLD FRONT ARRIVES LATER IN THE DAY TODAY. AHEAD OF THE FRONT...
THE SOUTHERLY FLOW WILL LIKELY SCOUR OUT THE COLD AIR FROM ALL THE
VALLEYS... CHANGING PRECIPITATION TO RAIN. BUT THE COLD FRONT WILL
BRING SOME COOLER AIR BACK IN BEHIND IT... WITH RAIN CHANGING TO
SNOW. ONLY LIGHT SNOW ACCUMULATIONS EXPECTED LATER THIS AFTERNOON
IN THE MOUNTAINS.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
AS THE COLD FRONT MOVES INTO THE GULF OF MAINE... LOW PRESSURE
WILL DEVELOP AND TRACK NORTHEAST ALONG THE FRONT. THIS WILL ALLOW
THE RAIN/SNOW TO CONTINUE THROUGH THE FIRST HALF OF THE NIGHT
ESPECIALLY TOWARD THE COAST. TEMPERATURES FALL INTO THE 20S AND
30S BY MORNING.
WEAK HIGH PRESSURE MOVES QUICKLY EAST ACROSS THE AREA BRINGING
MOSTLY CLEAR SKIES INITIALLY... WITH INCREASING CLOUDS LATER IN
THE DAY AS THE NEXT TROUGH APPROACHES FROM THE WEST. TEMPERATURES
RISE INTO THE 40S.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
LARGE SCALE 500 MB PATTERN GENERALLY HOLDS ONTO ITS +PNA
CHARACTERISTICS WELL INTO NEXT WEEK... AND TROUGHING OVER THE
EASTERN HALF OF THE CONUS WOBBLES AROUND SOMEWHAT. THIS WILL
KEEP THE TROUGH ACTIVE WITH WEAK WAVES MOVING AROUND THE BASE OF
THE TROUGH... AND DEVELOP /MOSTLY/ WEAKER SURFACE LOWS THAT WILL
TRACK QUICKLY UP THE COAST. EACH WAVE WILL ALSO DRAG
INCREMENTALLY COLDER AIR SOUTHEAST ACROSS THE CANADIAN PRAIRIE... AND
INTO THE NORTHEASTERN UNITED STATES... AND BY SUNDAY AND MONDAY
WILL LIKELY SEE TEMPERATURES DROP A LITTLE BELOW NORMAL... BUT BY
NO MEANS AS COLD AS IT WAS EARLIER THIS MONTH.
THE FIRST SYSTEM LOOKS TO PRODUCE MAINLY RAIN OR SNOW SHOWERS... AS
THE SOUTHERN STREAM WAVE AND THE NORTHERN STREAM WAVE PASS EACH
OTHER IN THE NIGHT. COASTAL ZONES CAN EXPECT MAINLY RAIN ON
THURSDAY...WITH SNOW MORE LIKELY IN THE MOUNTAINS IN THE
AFTERNOON... AS THE UPPER LEVEL TROUGH SWINGS JUST TO THE NORTH.
FRIDAY LOOKS COOLER... BUT STILL ABOVE NORMAL... WITH SOME
SUNSHINE.
THE NEXT SYSTEM MOVES IN FRIDAY NIGHT AS SOUTHERN STREAM OVER THE
GULF OF MEXICO AND MORE NORTHERN CLOSED LOW ATTEMPT TO INTERACT.
MODELS DIFFER QUITE A BIT.... WITH THE 00Z EURO SHOWING A PHASING
SYSTEM... AND ACCUMULATING SNOWFALL... WHILE THE 00Z GFS SHOWS
LESS PHASING AND TOO FAR TO OUR EAST TO PRODUCE MORE THAN SNOW
SHOWERS. ONE FINAL 500MB WAVE FOLLOW THIS SYSTEM SATURDAY NIGHT...
AND USHERS IN A RETURN TO WINTER EARLY NEXT WEEK.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
SHORT TERM...
EXPECT CONDITIONS TO DETERIORATE INTO THE IFR RANGE THIS MORNING
AS RAIN SPREADS INTO THE REGION. FOG IS ALSO POSSIBLE AS MOIST AIR
MOVES OVER THE SNOW PACK. A COLD FRONT WILL PUSH ACROSS THE AREA
AND BEGIN TO CLEAR THINGS OUT AGAIN LATER TONIGHT INTO EARLY
WEDNESDAY.
LONG TERM...
EXPECT PRECIPITATION THURSDAY AND SATURDAY... WITH A BREAK ON FRIDAY.
FLIGHT RESTRICTIONS MAY BE MINIMAL AND INTERMITTENT WEDNESDAY
NIGHT INTO THURSDAY... THEN EXPECT VFR FRIDAY. MAY SEE JUST ANOTHER
ROUND OF SNOW SHOWERS ON SATURDAY... ALTHOUGH MODELS DO
DIFFER... AND COULD SEE A STEADY SNOWFALL... WITH EXTENDED IFR
POSSIBLE.
&&
.MARINE...
SHORT TERM...EXPECT SOUTHERLY WINDS TO GUST AS HIGH AS 25 OR 30 KT
THROUGH THE EARLY AFTERNOON BEFORE SUBSIDING AS THE FRONT ARRIVES.
WAVE HEIGHTS WILL STAY ABOVE 5 FEET OVER THE OUTER WATERS THROUGH
AT LEAST THIS EVENING AND POSSIBLY THROUGH WEDNESDAY MORNING OR
LONGER.
LONG TERM...POSSIBLE SCA CONDITIONS IN SW FLOW LATE FRIDAY AND
FRIDAY NIGHT... BUT HIGHER CONFIDENCE IN SCA... AND POSSIBLE GALES
IN NW FLOW BEHIND LOW PRESSURE LATE SATURDAY INTO SUNDAY.
&&
.HYDROLOGY...
STILL SOME ICE JAMS OUT THERE... AND LOOKS LIKE SOME ICE MOVEMENT
IS POSSIBLE TODAY... BUT GRADUAL COOLING SHOULD MITIGATE THE ICE
JAM FLOOD THREAT AS THE WEEK PROGRESSES. A FLOOD WARNING CONTS FOR
THE SUGAR RIVER AT CLAREMONT.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ151-
153.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR ANZ150-152-
154.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAY ME
824 AM EST TUE JAN 14 2014
.SYNOPSIS...
A SERIES OF WEAK LOW PRESSURE SYSTEMS WILL TRACK NORTHEAST ALONG
THE EASTERN SEABOARD THIS WEEK. EACH OF THESE LOWS PROVIDE A ROUND
OF MAINLY LIGHT PRECIPITATION... AND EACH ONE WILL ALSO BRING
WAVES OF COLDER AIR. THE FIRST SYSTEM CROSSES THE REGION TODAY...
AND WILL BRING SOME SPOTTY FREEZING RAIN IN THE HILLS AND
MOUNTAINS... BEFORE CHANGING TO RAIN ON TUESDAY. ANOTHER SYSTEM
WILL BRUSH THE COAST OF NEW ENGLAND ON THURSDAY. WE WILL SEE
ANOTHER ONE DAY BREAK ON FRIDAY... BEFORE ANOTHER SYSTEM MOVES IN
FRIDAY NIGHT AND SATURDAY.... WHEN IT WILL LIKELY BE COLD ENOUGH
TO PRODUCE MAINLY SNOW.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
HAVE UPDATED GRIDS BASED ON CURRENT CONDITIONS. TEMPS HAVE ALREADY
WARMED TO THEIR HIGHS IN SOME LOCATIONS...BUT SHOULD LEVEL OFF
OVER THE NEXT COUPLE HOURS. THIS WILL ALLOW FOR AREAS OF FREEZING
RAIN...BUT THEY WILL BE LIMITED TO THE COLDEST SECTIONS OF THE
ADVISORY REGION. EXPECT PATCHY FOG TODAY.
LATEST HRRR RUN BRINGS THE BACK EDGE OF THE PRECIP OUT OF NH BY
AROUND 02Z. IN THE MEANTIME...PERIODS OF RAIN WILL CONTINUE
THROUGHOUT THE DAY.
PREV DISC...
RAIN NOW SLOWLY ARRIVING FROM THE WEST. TEMPERATURES
STILL AT OR BELOW FREEZING IN SPOTTY LOCATIONS IN THE HILLY AREAS
FROM CENTRAL NEW HAMPSHIRE NORTHEASTWARD INTO WEST CENTRAL MAINE.
STILL A THREAT FOR SOME LIGHT ICING THIS MORNING IN THESE AREAS.
SOUTHERN SOMERSET COUNTY... HOWEVER... HAS RISEN SAFELY ABOVE
FREEZING AND THUS FREEZING RAIN IS NO LONGER EXPECTED THERE. THE
ADVISORY HAS BEEN DROPPED FOR SOUTHERN SOMERSET COUNTY ONLY.
ORIGINAL DISCUSSION...
RAIN HAS BEEN SLOW TO MOVE INTO THE REGION OVERNIGHT... BUT IS
FINALLY SHOWING SIGNS OF REACHING THE WESTERN PART OF THE FORECAST
AREA EARLY THIS MORNING. TEMPERATURES ARE HIGHLY VARIABLE ACROSS
THE HILLS AND MOUNTAINS. SOME MESONET STATIONS ACROSS THIS AREA
ARE IN THE 40S... WHILE OTHER AREAS ARE NEAR OR BELOW FREEZING. AS
A RESULT... STILL EXPECT POCKETS OF FREEZING RAIN THROUGH THE
MORNING HOURS. THE VARIABLE TEMPERATURES MAY ACTUALLY MAKE IT MORE
DANGEROUS WHEN DRIVING AS IT MAKES IT MORE LIKELY TO RUN ACROSS
UNEXPECTED AREAS OF ICING. SOME PARTS OF MERRIMACK AND BELKNAP
COUNTY ARE BELOW FREEZING WITH RAIN SPREADING IN THIS MORNING. DID
NOT EXPAND THE ADVISORY FOR THESE AREAS AS THE POCKETS OF
SUBFREEZING TEMPERATURES ARE VERY LOCALIZED AND CAN BE HANDLED
WITH A SPECIAL WEATHER STATEMENT IF THEY DO NOT RISE BEFORE THE
RAIN ARRIVES. WILL CONTINUE TO MONITOR MESONET TEMPERATURE
READINGS THROUGH THE MORNING AND MAY BE ABLE TO CANCEL PARTS OF
THE ADVISORY EARLY AS TEMPERATURES WARM ABOVE FREEZING.
COLD FRONT ARRIVES LATER IN THE DAY TODAY. AHEAD OF THE FRONT...
THE SOUTHERLY FLOW WILL LIKELY SCOUR OUT THE COLD AIR FROM ALL THE
VALLEYS... CHANGING PRECIPITATION TO RAIN. BUT THE COLD FRONT WILL
BRING SOME COOLER AIR BACK IN BEHIND IT... WITH RAIN CHANGING TO
SNOW. ONLY LIGHT SNOW ACCUMULATIONS EXPECTED LATER THIS AFTERNOON
IN THE MOUNTAINS.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
AS THE COLD FRONT MOVES INTO THE GULF OF MAINE... LOW PRESSURE
WILL DEVELOP AND TRACK NORTHEAST ALONG THE FRONT. THIS WILL ALLOW
THE RAIN/SNOW TO CONTINUE THROUGH THE FIRST HALF OF THE NIGHT
ESPECIALLY TOWARD THE COAST. TEMPERATURES FALL INTO THE 20S AND
30S BY MORNING.
WEAK HIGH PRESSURE MOVES QUICKLY EAST ACROSS THE AREA BRINGING
MOSTLY CLEAR SKIES INITIALLY... WITH INCREASING CLOUDS LATER IN
THE DAY AS THE NEXT TROUGH APPROACHES FROM THE WEST. TEMPERATURES
RISE INTO THE 40S.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
LARGE SCALE 500 MB PATTERN GENERALLY HOLDS ONTO ITS +PNA
CHARACTERISTICS WELL INTO NEXT WEEK... AND TROUGHING OVER THE
EASTERN HALF OF THE CONUS WOBBLES AROUND SOMEWHAT. THIS WILL
KEEP THE TROUGH ACTIVE WITH WEAK WAVES MOVING AROUND THE BASE OF
THE TROUGH... AND DEVELOP /MOSTLY/ WEAKER SURFACE LOWS THAT WILL
TRACK QUICKLY UP THE COAST. EACH WAVE WILL ALSO DRAG
INCREMENTALLY COLDER AIR SOUTHEAST ACROSS THE CANADIAN PRAIRIE... AND
INTO THE NORTHEASTERN UNITED STATES... AND BY SUNDAY AND MONDAY
WILL LIKELY SEE TEMPERATURES DROP A LITTLE BELOW NORMAL... BUT BY
NO MEANS AS COLD AS IT WAS EARLIER THIS MONTH.
THE FIRST SYSTEM LOOKS TO PRODUCE MAINLY RAIN OR SNOW SHOWERS... AS
THE SOUTHERN STREAM WAVE AND THE NORTHERN STREAM WAVE PASS EACH
OTHER IN THE NIGHT. COASTAL ZONES CAN EXPECT MAINLY RAIN ON
THURSDAY...WITH SNOW MORE LIKELY IN THE MOUNTAINS IN THE
AFTERNOON... AS THE UPPER LEVEL TROUGH SWINGS JUST TO THE NORTH.
FRIDAY LOOKS COOLER... BUT STILL ABOVE NORMAL... WITH SOME
SUNSHINE.
THE NEXT SYSTEM MOVES IN FRIDAY NIGHT AS SOUTHERN STREAM OVER THE
GULF OF MEXICO AND MORE NORTHERN CLOSED LOW ATTEMPT TO INTERACT.
MODELS DIFFER QUITE A BIT.... WITH THE 00Z EURO SHOWING A PHASING
SYSTEM... AND ACCUMULATING SNOWFALL... WHILE THE 00Z GFS SHOWS
LESS PHASING AND TOO FAR TO OUR EAST TO PRODUCE MORE THAN SNOW
SHOWERS. ONE FINAL 500MB WAVE FOLLOW THIS SYSTEM SATURDAY NIGHT...
AND USHERS IN A RETURN TO WINTER EARLY NEXT WEEK.
&&
.AVIATION /13Z TUESDAY THROUGH SATURDAY/...
SHORT TERM...
EXPECT CONDITIONS TO DETERIORATE INTO THE IFR RANGE THIS MORNING
AS RAIN SPREADS INTO THE REGION. FOG IS ALSO POSSIBLE AS MOIST AIR
MOVES OVER THE SNOW PACK. A COLD FRONT WILL PUSH ACROSS THE AREA
AND BEGIN TO CLEAR THINGS OUT AGAIN LATER TONIGHT INTO EARLY
WEDNESDAY.
LONG TERM...
EXPECT PRECIPITATION THURSDAY AND SATURDAY... WITH A BREAK ON FRIDAY.
FLIGHT RESTRICTIONS MAY BE MINIMAL AND INTERMITTENT WEDNESDAY
NIGHT INTO THURSDAY... THEN EXPECT VFR FRIDAY. MAY SEE JUST ANOTHER
ROUND OF SNOW SHOWERS ON SATURDAY... ALTHOUGH MODELS DO
DIFFER... AND COULD SEE A STEADY SNOWFALL... WITH EXTENDED IFR
POSSIBLE.
&&
.MARINE...
SHORT TERM...EXPECT SOUTHERLY WINDS TO GUST AS HIGH AS 25 OR 30 KT
THROUGH THE EARLY AFTERNOON BEFORE SUBSIDING AS THE FRONT ARRIVES.
WAVE HEIGHTS WILL STAY ABOVE 5 FEET OVER THE OUTER WATERS THROUGH
AT LEAST THIS EVENING AND POSSIBLY THROUGH WEDNESDAY MORNING OR
LONGER.
LONG TERM...POSSIBLE SCA CONDITIONS IN SW FLOW LATE FRIDAY AND
FRIDAY NIGHT... BUT HIGHER CONFIDENCE IN SCA... AND POSSIBLE GALES
IN NW FLOW BEHIND LOW PRESSURE LATE SATURDAY INTO SUNDAY.
&&
.HYDROLOGY...
STILL SOME ICE JAMS OUT THERE... AND LOOKS LIKE SOME ICE MOVEMENT
IS POSSIBLE TODAY... BUT GRADUAL COOLING SHOULD MITIGATE THE ICE
JAM FLOOD THREAT AS THE WEEK PROGRESSES. A FLOOD WARNING CONTS FOR
THE SUGAR RIVER AT CLAREMONT.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...FREEZING RAIN ADVISORY UNTIL NOON EST TODAY FOR MEZ007>009-012-
013.
NH...FREEZING RAIN ADVISORY UNTIL NOON EST TODAY FOR NHZ001>006.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ151-
153.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR ANZ150-152-
154.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
745 AM EST TUE JAN 14 2014
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 329 AM EST TUE JAN 14 2014
A BURST OF SNOW WILL MOVE INTO SOUTHWEST MICHIGAN TOWARD MID DAY.
THE STEADIEST SNOW WILL OCCUR NORTH OF I-96. THIS SNOW SHOULD
DIMINISH ACROSS AREAS SOUTH OF I-96 BY LATE AFTERNOON...WHILE IT
SHOULD CONTINUE ACROSS CENTRAL LOWER MICHIGAN. THEN BY TONIGHT MORE
SNOW WILL ROTATE ACROSS ALL OF SOUTHWEST MICHIGAN. THIS SNOW WILL
FINALLY DIMINISH TOWARD MID DAY WEDNESDAY. WINDS WILL BECOME BRISK
BY TONIGHT CAUSING BLOWING AND DRIFTING SNOW.
WHERE THE SNOW IS THE MOST PERSISTENT...MAINLY NORTH OF A MUSKEGON
TO MOUNT PLEASANT LINE...5 TO 9 INCHES OF SNOW CAN BE EXPECTED BY
NOON WEDNESDAY. AREAS SOUTH OF A MUSKEGON TO MOUNT PLEASANT LINE
SHOULD SEE BETWEEN 2 AND 5 INCHES OF SNOW BY NOON WEDNESDAY.
ANOTHER CLIPPER ARRIVES LATE WEDNESDAY NIGHT INTO THURSDAY. THIS
SYSTEM SHOULD PRODUCE ANOTHER 1 TO 3 INCHES OF SNOW.
&&
.UPDATE...
ISSUED AT 745 AM EST TUE JAN 14 2014
I DID SOME MINOR CHANGES TO OUR SHORT TERM GRIDS TO SLOW DOWN THE
START OF THE SNOW ACROSS THE AREA. THE LATEST RUNS OF THE HRRR AND
RAP MODELS...PLUS THE 06Z NAM12 SUGGEST THE SNOW WILL NOT GET
STARTED IN OUR WESTERN COUNTIES UNTIL BETWEEN NOON AND 1 PM. GIVEN
THE DRY AIR AHEAD OF THIS SYSTEM THAT WOULD MAKE SENSE TOO. ALSO
USING THE TIMING TOOL IT ALSO SUGGESTS EARLY AFTERNOON FOR THE
LAKE SHORE COUNTIES.
THE PRIMARY BAND OF SNOW WILL LIKELY NOT AMOUNT TO MUCH OVER MOST
OF THE CWA. THE NORTHERN COUNTIES... IN THE ADVISORY AREA... COULD
SEE 1 TO 3 INCHES WITH THE 3 INCH AMOUNTS BEING NORTH OF ROUTE 10.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 329 AM EST TUE JAN 14 2014
WILL ONLY MAKE MINOR TWEAKS TO THE CURRENT HEADLINES. FIRST WILL
DELAY THE START TIME UNTIL 16Z. THEN WILL ALSO ADD MUSKEGON COUNTY
TO THE ADVISORY.
VERY WRAPPED UP CLIPPER SYSTEM TO IMPACT THE REGION LATER TODAY AND
LINGER INTO THE FIRST HALF OF WED. MODEL TRENDS CONTINUE TO SHOW A
SLIGHTLY FURTHER NORTH TRACK TO THE SURFACE LOW...GENERALLY JUST
SOUTH OF HIGHWAY 10. THIS WILL KEEP THE STEADIEST SNOW ACROSS
CENTRAL LOWER WHERE THE ADVISORY IS PRESENTLY. EXPECT A BURST OF
WARM ADVECTION SNOW ARRIVING AROUND 16Z...WHEN THE ADVISORY WILL GO
INTO AFFECT. THIS SHOULD IMPACT AREAS NW OF A HOLLAND TO CLARE LINE
WITH THE STEADIEST SNOW...WITH AREAS SE SEEING A MORE SHORT LIVED
BURST.
THEN TOWARD LATE AFTERNOON WE WILL SEE A DRY SLOT PUNCH INTO THE
CWA. EXPECT MOST AREAS OUTSIDE OF THE ADVISORY AREA WILL SEE A LULL
IN THE SNOWFALL. IT SHOULD CONTINUE OVER THE ADVISORY REGION...BUT
SHOULD LIGHTEN UP SOMEWHAT.
THEN INTO MID/LATE EVENING...AND CONTINUING INTO WED MORNING...THE
DEFORMATION ZONE WILL DRAG ACROSS ALL THE CWA WITH A RETURN TO
STEADIER SNOWS. HAVE ADDED MUSKEGON COUNTY TO THE ADVISORY FOR
MAINLY A STEADIER SNOW DURING THIS PERIOD ALONG WITH SOME LAKE
ENHANCEMENT WITH A WSW FLOW. THE FLOW PIVOTS TO THE NW LATE TONIGHT
WHICH WILL SPRAY ALL THE LAKESHORE COUNTIES WITH SOME LAKE
ENHANCEMENT.
ACCUMS BY NOON WED SHOULD BE IN THE 5 TO 9 INCH RANGE FOR AREAS IN
THE ADVISORY...AND 2 TO 5 INCHES ELSEWHERE.
WE WILL NEED TO MONITOR THE WIND ASPECT OF THE SYSTEM TONIGHT. AS
WE GET INTO THE COLD ADVECTION ON THE BACKSIDE OF THE SYSTEM WSW
WINDS WILL INCREASE AND COULD LEAD TO SIGNIFICANT BLOWING AND
DRIFTING. WE MAY NEED TO EXPAND THE ADVISORY IN AREA IF THIS
BECOMES MORE OF A CONCERN.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 329 AM EST TUE JAN 14 2014
SNOW SHOWERS ARE EXPECTED INTO FRIDAY THEN IT MAY BE QUIET INTO
EARLY NEXT WEEK. TEMPERATURES WILL BE COLDER THEN OVER THE PAST
WEEKEND BUT NOT REALLY SIGNIFICANTLY COLDER THAN NORMAL. SOME
WARMING IS EXPECTED LATE IN THE WEEKEND INTO EARLY NEXT WEEK BUT IT
WILL NOT LAST LONG.
WE CURRENTLY HAVE A SIGNIFICANT STRATOSPHERIC WARMING EVENT OVER
NORTHERN RUSSIA (SIBERIA)... NEAR 10MB. THIS MATTERS BECAUSE THE
RESULT OF THIS IS TYPICALLY A SPLIT IN THE POLAR VORTEX. YOU MAY
REMEMBER WE SAW THIS HAPPEN DURING THE FIRST WEEK OF JANUARY TOO.
SIMILARLY THE POLAR VORTEX SPLIT THEN TOO. SINCE THE MODELS DO IN
FACT SHOW THIS HAPPENING ONCE AGAIN AND ONCE AGAIN WE HAVE
STRATOSPHERIC WARMING EVENT IT WOULD SEEM THIS EVENT WILL IMPACT OUR
WEATHER OVER THE NEXT WEEK OR SO.
THE RESULT OF THE SPLITTING OF THE POLAR VORTEX WILL BE A SOUTHWARD
DISPLACEMENT PART OF THE POLAR VORTEX OVER NORTH AMERICA. ALL THE
MODELS SHOW THIS. THE ONLY QUESTION IS TO WHAT EXTENT THIS HAPPENS.
THE PART OF THE POLAR VORTEX OVER NORTH AMERICA DROPS SOUTH FROM
ARCTIC OCEAN SHORES OF CANADA TO SOUTHERN HUDSON BAY BY SUNDAY.
CLEARLY THIS WILL BRING THE VERY COLD AIR MUCH CLOSER TO MICHIGAN
THAN IT HAS BEEN OVER THE PAST FOUR DAYS.
WHILE THE POLAR VORTEX DIGS SOUTH OVER THE NEXT FEW DAYS...THE ECMWF
DRIVES A SHORTWAVE CURRENTLY RIDING OVER THE TOP OF THE UPPER RIDGE
IN SOUTHERN ALASKA SOUTH OF CHICAGO BY FRIDAY MORNING. IT DIGS IT SO
STRONGLY IT CLOSES OFF AN UPPER LOW WELL SOUTHWEST OF CHICAGO BY
FRIDAY MORNING. THIS HAS CONTINUITY IN THE ECMWF FOR AT LEAST THE
PAST 3 RUNS BUT THE 14TH/00Z VERSION OF THIS IS FARTHER SOUTH THAN
THE OTHERS. THE CANADIAN GEM IS SIMILAR WITH THIS SYSTEM TOO. IN ANY
EVENT THE AMOUNT OF DIGGING OF THESE SYSTEMS WILL MAKE A DIFFERENCE
IN HOW COLD WE GET AND HOW MUCH SNOW WE GET. MODEL AGREEMENT IS GOOD
TILL THURSDAY MORNING...THEN THAT ECMWF MORE STRONGLY DIGGING UPPER
WAVE BRINGS COLDER AIR SIGNIFICANTLY FARTHER SOUTH FRIDAY THAN IS
SHOWN BUT THE GFS. THIS ALSO RESULTS IN THE ECMWF BEING SLOWER THAN
THE GFS IN TERMS OF MOVING SYSTEMS THROUGH THE AREA. BY THE WAY THE
CANADIAN GEM IS MORE SIMILAR TO THE ECMWF THAN THE GFS ON THIS
FEATURE.
THE RESULT OF ALL THIS IS RIDGING WEDNESDAY NIGHT HEAD OF THE NEXT
SYSTEM. THAT SHOULD QUIET DOWN ANY LAKE EFFECT THAT WOULD LINGER
INTO WEDNESDAY AFTERNOON BY EARLY WEDNESDAY EVENING. AFTER MIDNIGHT
A SOUTHWEST FLOW EVENT SETS UP AND THIS SHOULD BRING SNOW TO THE
LAKE SHORE COUNTIES NORTH OF MKG BEFORE SUNRISE THURSDAY MORNING.
WHAT HAPPENS AFTER THAT IS HARD TO TOTALLY SAY. IF THE ECMWF IS
CORRECT THERE WOULD BE A LONGER PERIOD OF SNOW ON THURSDAY AND IT
WOULD AMOUNT TO MORE SNOW COVERING A LARGELY AREA OF OUR CWA. IF THE
GFS IS CORRECT WE DO NOT GET MUCH SNOW ANYWHERE IN OR CWA AS MOST OF
THE DYNAMICS WOULD BE OVER UPPER MICHIGAN.
SINCE THE GFS DOES NOT DIG THE LEAD SYSTEM AS MUCH...TRAILING WAVE
ENERGY DEVELOPS A SYSTEM ON SATURDAY THAT THE ECMWF AND CANADIAN DO
NOT HAVE. SHORTWAVE RIDGING BETWEEN THE DEPARTING TROUGH AND THE
NEXT WAVE ROTATING AROUND THE POLAR VORTEX WILL FAVOR A DRY PERIOD
FROM SAT INTO MONDAY WITH MILDER TEMPERATURES. THE NEXT SYSTEM WOULD
BE THE MIDDLE OF NEXT WEEK AND THAT WOULD BRING DOWN VERY COLD AIR
BEHIND IT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 703 AM EST TUE JAN 14 2014
CURRENTLY VFR CONDITIONS PREVAIL AT MOST OF THE TAF SITES...LAN
HAS MVFR IN HAZE. AS THE COMPACT STORM OVER THE CENTRAL PLAINS
HEADS EAST SOUTHEAST INTO CENTRAL LOWER MICHIGAN BY EARLY THIS
EVENING IT HAS A BAND OF SNOW ABOUT 3 HOURS WIDE IN FRONT OF IT.
THIS WILL SWEEP THROUGH THE TAF SITES WITH IFR CONDITIONS IN THE
18Z TO 00Z TIME FRAME. WINDS WILL BECOME GUSTY THIS AFTERNOON TOO.
ONCE THAT BAND MOVES THROUGH I EXPECT THE DRY SLOT TO END THE SNOW
FOR SEVERAL HOURS. WHILE THAT IS GOING ON EXPECT MVFR CIGS. AFTER
06Z THE SNOW BAND ON THE WEST SIDE OF THE SYSTEM WILL MOVE IN WITH
GUSTY WINDS. THIS WILL CAUSE IFR CONDITIONS WITH SNOW AND BLOWING SNOW.
&&
.MARINE...
ISSUED AT 329 AM EST TUE JAN 14 2014
ISSUED SMALL CRAFT ADVISORY FOR LATER TODAY. THEN RAMPED UP TO A
GALE WARNING LATE TONIGHT INTO WED MORNING.
&&
.HYDROLOGY...
ISSUED AT 325 PM EST MON JAN 13 2014
FLOOD ADVISORIES ARE IN EFFECT FOR THE KALAMAZOO RIVER AT NEW
RICHMOND...THE SYCAMORE CREEK AT HOLT...AND THE PERE MARQUETTE RIVER
AT SCOTTVILLE. ALL THESE RIVERS ARE ABOVE BANKFULL BUT BELOW FLOOD
STAGE. MINOR FLOODING ALONG LOW LYING AREAS ADJACENT TO THE RIVERS
IS THE MAIN IMPACT.
ELSEWHERE...RISES CONTINUE ON MANY LARGE AND SMALL RIVERS AND
STREAMS...BUT NO IMMEDIATE FLOODING RISKS ARE NOTED. ICE COVERAGE ON
THE GRAND AT ROBINSON TWP IS THINNING AND CURRENTLY STABLE (NOT
MOVING IN CHUNKS). THIS IS GOOD NEWS AND REDUCES THE THREAT FOR ICE
JAMS. NO ABRUPT RISES ARE SHOWN ON AREA HYDROGRAPHS...ANOTHER
INDICATOR THAT ICE IS BEHAVING.
THE OUTLOOK FOR RIVERS THIS WEEK IS FOR THEM TO BE CRESTING (IF THEY
HAVEN`T ALREADY) AND THEN FALLING BACK DOWN. A REFORMATION OF ICE IS
LIKELY ON RIVERS THAT ONLY HAD SMALL RISES FROM THE RECENT RAINS AND
SNOW MELT. MAXIMUM ICE DEVELOPMENT WOULD LIKELY OCCUR OVER THE
WEEKEND BUT TEMPERATURES ESPECIALLY AT NIGHT WILL BE CONDUCIVE TO
ICE DEVELOPMENT.
SNOW WATER EQUIVALENT VALUES (VIA NOHRSC ANALYSIS AND IN-SITU
MEASUREMENTS) ARE QUITE HIGH ACROSS SW LOWER MI...GENERALLY BETWEEN
1 AND 4 INCHES. THESE VALUES WILL ONLY BE GOING UP THIS WEEK AS WE
ADD FRESH SNOW TO A VERY DENSE AND CRUSTY SNOW PACK. SOMETHING TO BE
THINKING ABOUT WHENEVER THE NEXT THAW COMES.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY FROM 11 AM THIS MORNING TO 1 PM EST
WEDNESDAY FOR MIZ037>040-043>046-050.
LM...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 1 AM EST
WEDNESDAY FOR LMZ844>849.
GALE WARNING FROM 1 AM TO 11 AM EST WEDNESDAY FOR LMZ844>849.
&&
$$
UPDATE...WDM
SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...WDM
AVIATION...WDM
HYDROLOGY...HOVING
MARINE...OSTUNO
AREA FORECAST DISCUSSION
NWS BILLINGS MT
412 AM MST TUE JAN 14 2014
.SHORT TERM...VALID FOR TDY AND WED...
MOIST NORTHWESTERLY FLOW ALOFT WITH ROOTS IN A PINEAPPLE
CONNECTION IS BEING REAL EFFICIENT AND PRODUCING SO FOR SOUTHERN
PORTIONS OF SOUTH CENTRAL MONTANA AND NORTHERN WYOMING. BAND IS
ORIENTED NORTHWEST TO SOUTHEAST AN IS MOST INTENSE OVER STILLWATER
AND CARBON COUNTIES WHERE SOME WARM AIR ADVECTION IS BEGINNING TO
NUDGE THE COLD FRONT BACK TO THE EAST. THIS CAN BE SEEN AS
BILLINGS PRESSURE IS RISING LIVINGSTON IS FALLING...SO
FRONTOGENESIS IS PICKING ALONG THE BAND...WHICH IS ALSO AIDED BY
SOME UPSLOPE INTO THE PRYOR MOUNTAINS AND BEARTOOTH AND RED LODGE
FOOTHILLS.
FIRST FORECAST CHALLENGE IS HOW FAST DOES THIS BAND MIGRATE
EASTWARD BEFORE RISING HEIGHTS STABILIZE THE AIRMASS TOO MUCH AND
DOWNSLOPE ERODES THE PRECIPITATION. RUC MODEL IS THE ONLY ONE THAT
REALLY TRACKED THE PRECIP WELL EARLIER AND IT SHIFTS THE AXIS INTO
YELLOWSTONE AND BIG HORN COUNTIES FOR A FEW HOURS THIS MORNING
BEFORE IT BEGINS TO WANE. THIS SEEMS TO REFLECT CURRENT RADAR
TRENDS SO INCREASING POPS FOR THE CENTRAL ZONES. JUST GOT REPORT
OF 12 TO 16 INCHES OF SNOW IN RED LODGE AND GIVEN CURRENT RADAR
TRENDS WILL UPGRADE RED LODGE FOOTHILLS AND EASTERN CARBON COUNTY
TO A WINTER STORM WARMING. WILL EXTEND THE WINTER WEATHER ADVISORY
FOR BIG HORN AND SHERIDAN COUNTY WYOMING UNTIL 10 AM. EXPECT AN
INCH POSSIBLE IN BILLINGS AND AN ADDITIONAL COUPLE OF INCHES FOR
THE ADVISORY LOCATIONS AND ANOTHER 3 FOR THE WARNING AREA.
PROBABLY SOME AREAS OF BLOWING AND DRIFTING DUE TO WINDS ABOVE 20
MPH BUT EARLY SPOTTER REPORTS SAY IT WAS STICKY AND NOT REALLY
MOVING.
OTHERWISE AS LEESIDE TROUGHING WINDS INCREASE...TEMPERATURES
INCREASE AND PRECIPITATION DECREASES. WEDNESDAY WILL BE A WINDY
DAY BUT ANY FRONTAL PUSH LOOKS TO BE LATER AT NIGHT...SO NOT
CONCERNED ABOUT LOW ELEVATION WINDS. LOOKS LIKE WIND ADVISORY MAY
BE NEEDED FOR GAP FLOW AREAS BUT WILL WAIT FOR ANOTHER ROUND OF
MODELS TO DECIDE. BORSUM
.LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON...
DRY NW FLOW ON THE E SIDE OF AN UPPER RIDGE WILL BE OVER THE
FORECAST AREA INTO SAT. HEIGHTS BEGIN TO FALL ON SUN IN RESPONSE
TO A WEAK WAVE MOVING THROUGH THE FLOW. HOWEVER...AIRMASS LOOKED
DRIER THAN IN PREVIOUS MODEL RUNS SO HAVE LIMITED LOW POPS TO JUST
THE MOUNTAINS. GFS HAD A SHORTWAVE APPROACHING THE AREA ON MON
FROM THE N WHILE ECMWF MAINTAINED A QUIETER NW FLOW. FOR
NOW...JUST HAD SOME MOUNTAIN POPS FOR MON. A DRY NW FLOW
PREVAILED ON TUE. THERE WILL BE PERIODS OF LEE TROUGHINESS
THROUGH THE EXTENDED WHICH WILL PRODUCE GUSTY WINDS IN THE GAP
FLOW AREAS AND BIG TIMBER. TEMPERATURES WILL BE ABOVE SEASONAL
VALUES THROUGH THE PERIOD AND MADE SOME ADJUSTMENTS TO THEM BASED
ON LATEST GUIDANCE. ARTHUR
&&
.AVIATION...
MVFR TO IFR CONDITIONS WILL AFFECT AREAS FROM E OF KLVM TO SW OF
KMLS...INCLUDING KBIL AND KSHR...THIS MORNING DUE TO SNOW.
LOCALIZED LIFR CONDITIONS WILL ALSO BE POSSIBLE. CONDITIONS WILL
IMPROVE TO VFR LATE THIS MORNING INTO THIS AFTERNOON. THE
BEARTOOTHS...ABSAROKAS AND NE BIG HORNS WILL BE OBSCURED THIS
MORNING. EXPECT LOCALIZED OBSCURATION OVER THE CRAZYS. MOUNTAIN
OBSCURATION WILL DECREASE THIS AFTERNOON. VFR WILL RETURN TO THE
ENTIRE AREA TONIGHT. ARTHUR
&&
.PRELIMINARY POINT TEMP/POPS...
TDY WED THU FRI SAT SUN MON
-------------------------------------------------------
BIL 042 031/051 028/041 030/049 028/050 032/047 028/044
7/J 11/N 10/B 00/U 00/U 01/U 11/B
LVM 042 034/049 030/040 030/047 033/047 038/046 032/043
1/N 11/N 10/B 00/N 00/U 01/N 11/B
HDN 039 023/049 023/039 020/045 018/048 022/043 019/040
6/J 11/N 00/U 00/U 00/U 01/U 11/B
MLS 034 025/044 022/034 019/041 020/040 022/040 018/035
1/N 11/N 10/N 00/B 00/U 01/U 11/B
4BQ 034 025/048 024/034 019/042 018/042 024/043 020/039
2/J 01/N 00/N 00/B 00/U 01/U 11/U
BHK 031 024/045 020/027 018/037 017/039 022/041 017/034
1/N 11/N 11/N 00/B 00/B 01/U 11/B
SHR 037 023/050 022/038 020/045 023/047 023/047 022/044
8/J 01/U 10/B 00/B 00/U 00/U 10/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...WINTER WEATHER ADVISORY IN EFFECT UNTIL 10 AM MST THIS
MORNING FOR ZONE 38.
WINTER STORM WARNING IN EFFECT UNTIL 10 AM MST THIS MORNING
FOR ZONES 39-56.
WY...WINTER WEATHER ADVISORY IN EFFECT UNTIL 10 AM MST THIS
MORNING FOR ZONE 99.
WINTER WEATHER ADVISORY IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON FOR ZONE 98.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
925 AM EST TUE JAN 14 2014
.SYNOPSIS...WEAK LOW PRESSURE AFFECTS THE WEATHER OF THE CAROLINAS
FOR MUCH OF THE DAY...WITH WEAK HIGH PRESSURE BUILDING IN WITH DRIER
AIR TONIGHT THROUGH WEDNESDAY. AN ARCTIC COLD FRONT AND ACCOMPANYING
STRONG UPPER LEVEL TROUGH WILL THEN CROSS THE MIDDLE ATLANTIC REGION
AND INDUCE COASTAL LOW PRESSURE DEVELOPMENT WEDNESDAY NIGHT.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 925 AM TUESDAY...
WATER VAPOR IMAGERY SHOWED A MODERATELY STRONG MID-LEVEL SHORTWAVE
MOVING THROUGH THE EASTERN CAROLINAS IN A SOUTHWEST FLOW ALOFT...
AHEAD OF A 100KT 500MB JET THAT PUSHES ACROSS CENTRAL NORTH CAROLINA
DURING THE DAY. A MID-LEVEL TROUGH WITH A DRY PUNCH WAS MOVING EAST
ACROSS TENNESSEE AND APPROACHING THE FAR WESTERN PART OF THE STATE...
AND THIS DRY AIR WILL GRADUALLY MOVE ACROSS THE STATE DURING THIS
AFTERNOON. IN THE MEANTIME...THE 12Z KGSO SOUNDING INDICATED DEEP
MOISTURE WITH GOOD LOW-LEVEL MOISTURE TRANSPORT AND LIFT...PARTLY
NOTED BY 850MB WINDS GREATER THAN WHAT THE RAP WAS FORECASTING EARLY
THIS MORNING...AROUND 40KT. AS THE LIFTING SYNOPTIC FEATURES MOVE
EAST AND NORTHEAST...DRIER AIR SHOULD GRADUALLY MOVE ACROSS CENTRAL
NORTH CAROLINA THIS AFTERNOON. K INDICES ARE NEGATIVE BY 23Z EVEN AS
FAR EAST AS THE COASTAL PLAIN...WITH PRECIPITABLE WATER VALUES
FALLING TO 0.75 INCH OR LESS BY 00Z. LOOKING AT THE TIMING OF THE
DRIER AIR COMBINED WITH THE HRRR WRF RAINFALL FORECAST WOULD
INDICATE PERIODS OF RAIN AND DRIZZLE DRYING IN THE TRIAD AROUND
18Z...IN THE TRIANGLE AND FAYETTEVILLE BETWEEN 19Z AND 2030Z...AND
IN THE EASTERN COASTAL PLAIN BY 22Z. CLEARING MAY BE DELAYED FROM
THAT ABOUT AN HOUR...BUT IT SHOULD BE CLOSE. DID NOT MODIFY
TEMPERATURES MUCH...MAYBE A DEGREE LOWER...DUE TO THE ALREADY WARM
VALUES MOSTLY ONLY A CATEGORY OR TWO BELOW FORECAST MAXIMUMS. MOSTLY
CLEAR CONDITIONS FOR MUCH OF THE NIGHT WILL SUPPORT LOWS IN THE 30S.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 305 AM TUESDAY...
A SERIES OF STRONG SHORTWAVE TROUGHS WILL DIG SOUTHEASTWARD AND
AMPLIFY THE MEAN MID-UPPER TROUGH ACROSS THE SOUTHEAST STATES
THROUGH WED NIGHT. AN ARCTIC COLD FRONT...WHOSE EASTWARD PROGRESS
HAS TRENDED SLOWER IN NWP GUIDANCE OVER THE PAST COUPLE OF
DAYS...WILL ACCOMPANY THE TROUGH ALOFT...AND IS NOW FORECAST TO
CROSS CENTRAL NC DURING THE EVENING AND OVERNIGHT HOURS WED. THIS
SLOWER SOLUTION...AS THE LEAD SHORTWAVE IN THE SERIES TURNS NNE UP
THE SPINE OF THE APPALACHIANS AND WAITS FOR UPSTREAM ENERGY TO PUSH
THE TROUGH EASTWARD...WILL ALLOW TEMPERATURES TO WARM INTO THE
50S...WITH SKY COVER MOSTLY SUNNY EAST TO BECOMING PARTLY CLOUDY
WEST.
THE FORECAST - A BELOW AVERAGE ONE GIVEN CONTINUED LARGER THAN AVG
MODEL SPREAD - GETS MORE INTERESTING WED NIGHT...AS THE
AFOREMENTIONED SHORTWAVE ENERGY AND ASSOCIATED 150-180 METERS MID
LEVEL HEIGHT FALLS DIG ACROSS THE SAVANNAH BASIN AND OFFSHORE THE SC
COAST - A TRACK FAVORABLE FOR "NW FLOW" PRECIPITATION (NORTH OF THE
VORT TRACK) ACROSS NC. WHILE NWP GUIDANCE SUGGESTS A WEAK/OPEN
SURFACE WAVE MAY ACCOMPANY THE ARCTIC BOUNDARY ACROSS NC...SOME
DEGREE OF COASTAL DEVELOPMENT IS LIKELY AS AS THE STRONG FORCING FOR
ASCENT OVERSPREADS THE GULF STREAM AND LINGERING BAROCLINIC ZONE
JUST OFFSHORE - THE ONE THAT CROSSES OUR REGION TODAY. NWP GUIDANCE
HAS HAD A DIFFICULT TIME WITH BOTH THE TIMING/AMPLITUDE OF THE
APPROACHING SHORTWAVE TROUGHS...AS WELL AS UPON WHICH BOUNDARY - THE
QUASI-STATIONARY OFFSHORE ONE OR CROSSING ARCTIC ONE - THE PRIMARY
LOW DEVELOPS. THIS REMAINING QUESTION WILL HAVE RAMIFICATIONS ON
DURATION AND INLAND-EXTENT OF PRECIPITATION...WHOSE TYPE WOULD
TRANSITION FROM RAIN TO SNOW AS THE DEEP LAYER COOLING CRASHES COAST-
WARD PER BOTH PARTIAL THICKNESSES AND NAM BUFR SOUNDINGS WHOSE
PARENT MASS FIELDS AND QPF OF UP TO A TENTH OF AN INCH LIQUID
EQUIVALENT...CLOSELY RESEMBLE THE PREFERRED ECMWF/EC ENSEMBLE MEAN.
IN THIS LOW CONFIDENCE FORECAST...WILL INCREASE POPS INTO THE CHANCE
RANGE FROM WEST TO EAST DURING THE OVERNIGHT-EARLY THU HOURS...WITH
WORDING OF RAIN CHANGING TO SNOW. PRECIPITATION AMOUNTS WOULD LIKELY
BE LIGHT IN EITHER SCENARIO...SINCE AN UPSTREAM KICKER SHORTWAVE
WOULD LEAVE LITTLE TIME FOR THE OFFSHORE LOW TO LINGER OFF THE NC
COAST. THE CHANCE OF LIGHT SNOW WILL BE ADDED TO THE HWO LATER THIS
MORNING....THOUGH ASSOCIATED IMPACTS AT THIS TIME APPEAR TO BE VERY
MINIMAL. LOW TEMPERATURES CRASHING INTO THE 20S...USHERED IN BY A
BREEZY NW WIND...WITH GUSTS 20-30 MPH POSSIBLE.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 320 AM TUESDAY...
STRONGLY PROGRESSIVE NORTHWEST...SPLIT FLOW ALOFT WILL PREVAIL
THROUGH AT LEAST EARLY NEXT WEEK...AS A STRONG WESTERN RIDGE AND
EASTERN TROUGH PERSIST IN THE MEANS...WITH AN UNDERCUTTING SOUTHERN
STREAM ACROSS THE GOM AND SW ATLANTIC. IN THIS PATTERN...A VIGOROUS
SHORTWAVE TROUGH IN NW FLOW ALOFT AND ACCOMPANYING SURFACE FRONTAL
WAVE/SYSTEM WILL AFFECT CENTRAL NC EVERY COUPLE OF DAYS...WITH
PRONOUNCED BUT SHORT-LIVED POST-FRONTAL COLD...FOLLOWED BY ALSO
BRIEF PRE-FRONTAL MODIFICATION.
AS SUCH...THU WILL BE GENERALLY CLEAR AND CHILLY BETWEEN 40-45
DEGREES...FOLWITH A MOIST AIRMASS IN PLACE AND PERTURBATIONS MOVING
THROUGH IN
THE SOUTHWESTERLY FLOW... LIGHT SHOWERS ARE ONGOING ACROSS THE AREA.
THERE SHOULD BE AN INCREASE IN COVERAGE THROUGH THE MORNING AS THE
DEAMPLIFYING SHORTWAVE CROSSES THE AREA... AND LIFT IS ENHANCED BY
THE RIGHT ENTRANCE REGION OF THE JET. COLD FRONT WILL ENTER WESTERN
PART OF THE CWA AROUND 15Z... AND CLEAR THE CAROLINA COAST BY 00Z.
WINDS WILL BECOME WESTERLY AFTER THE FRONT PASSES... AND DRY AIR
MOVES IN TO THE AREA LATE TUESDAY INTO WEDNESDAY... WITH SKIES
BECOMING MOSTLY CLEAR. WITH A PERIOD OF SUN DURING THE AFTERNOON IN
THE WEST... HIGH TEMPERATURES WILL BE IN THE UPPER 50S. A MILD START
WILL LEAD TO HIGH TEMPERATURES IN THE LOW 60S IN THE EAST... DESPITE
THE POTENTIAL FOR CLOUD COVER TO LINGER INTO THE EARLY EVENING
HOURS. LOWED BY INCREASING CLOUDS AND MODERATION INTO THE
UPPER 40S TO LOWER 50S AHEAD OF THE NEXT SYSTEM FRI. FRONTAL WAVE
DEVELOPMENT IS LIKELY INVOF THE CAROLINA COAST LATE WEEK AS SPLIT
STREAMS ALIGN FAVORABLY FOR STRONG ASCENT CENTERED OFFSHORE THE
CAROLINAS...THOUGH ASSOCIATED SURFACE LOW DEVELOPMENT WILL BE FAST-
MOVING IN THE PROGRESSIVE FLOW. DESPITE LARGER THAN AVG MODEL SPREAD
IN THE MEDIUM RANGE...THERE IS A STRONG ENOUGH SIGNAL IN NWP
GUIDANCE...PARTICULARLY WITH THE WETTER ECMWF SOLUTIONS THAT HAVE
PROVEN MORE ACCURATE PARTICULARLY IN RECENT DAYS...SUCH THAT A SMALL
CHANCE OF PRECIPITATION - AGAIN LIKELY RAIN CHANGING TO SNOW - IS
JUSTIFIED FOR LATE FRI FRI NIGHT. COOLER SAT...THEN MODERATING
SUN...AHEAD OF THE NEXT CLIPPER-TYPE LOW SCHEDULED FOR MON...THOUGH
THIS ONE APPEARS MORE MOISTURE-STARVED AND FARTHER NORTH AS THE
LONGWAVE PATTERN RELAXES BRIEFLY AND THE ZONAL INDEX INCREASES EARLY
NEXT WEEK. ANOTHER ARCTIC AIR MASS WILL BE BUILDING ACROSS CANADA
EARLY TO MID NEXT WEEK...HOWEVER...SO THE NEXT BUCKLE IN THE FLOW
THAT BOTH THE GEFS AND EC ENSEMBLE MEAN DEPICTS WOULD SEND THIS AIR
MASS OUR WAY LATER NEXT WEEK.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 701 AM TUESDAY...
PERIODS OF LIGHT RAIN WILL CONTINUE THROUGH TUESDAY MORNING AHEAD OF
A COLD FRONT APPROACHING FROM THE WEST. CONDITIONS WILL BECOME MVFR
OVER THE NEXT FEW HOURS ACROSS THE AREA... WITH THE POTENTIAL FOR
IFR CONDITIONS AFTER 10Z. VFR CONDITIONS WILL RETURN FROM WEST TO
EAST... WITH RAPID CLEARING AFTER THE FRONT PASSES THROUGH THE AREA
BETWEEN 18Z TUES AND 00Z WED.
THE PATTERN REMAINS ACTIVE INTO THE WEEKEND... WITH THE POTENTIAL
FOR SUB-VFR CONDITIONS WITH CLIPPER TYPE SYSTEMS MOVING ACROSS THE
AREA FROM THE NORTHWEST WEDNESDAY AND EARLY SATURDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MWS/DJF
NEAR TERM...SEC/DJF
SHORT TERM...MWS
LONG TERM...MWS
AVIATION...SEC
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1006 AM EST TUE JAN 14 2014
.SYNOPSIS...
A SERIES OF SIGNIFICANT SHORTWAVE IMPULSES ROUNDING THE CREST OF
A PERSISTENT WEST-COAST UPPER RIDGE ARE EXPECTED TO CONTINUE
DIGGING INTO A LARGER-SCALE TROUGH FORMING EAST OF THE ROCKIES.
EACH PIECE OF UPPER-LEVEL ENERGY WILL CONTRIBUTE TO THE
MAINTENANCE OF THE TROUGHING...AND SUPPORT SUCCESSIVE INTRUSIONS
OF REINFORCING COLDER AIR INTO THE EASTERN U.S. IN THIS PATTERN
SURFACE WAVE DEVELOPMENT IS PROGGED NEAR THE EAST COAST BUT IT IS
DIFFICULT TO SAY HOW MUCH OR IF ANY OF THE COASTAL WAVES WILL
IMPACT THE AREA. THE HIGHEST CONFIDENCE FORECAST IS FOR A
MODERATELY COLDER PERIOD WITH DAILY TEMPERATURES TRENDING LOWER ON
THE WHOLE.
&&
.NEAR TERM /THROUGH TONIGHT/...
VERY LIGHT RAIN COVERS THE CWA SE OF KBFD AND IS ONLY SLOWLY
MOVING TO THE EAST. TIMING ON RECENT HRRR AND RUC RUNS ARE FAIRLY
CONSISTENT WITH GOING GRID POPS...AND WILL ONLY MAKE MINOR TWEAKS.
TEMPS SHOULD STAY LEVEL OVER MOST OF THE AREA FOR THE REST OF THE
DAY. A FEW DEG RISE IS POSS IN THE S...AND A FEW DEG FALL IS POSS
IN THE NW WHERE THE COLD AIR IS STARTING TO ARRIVE. WIND SHIFT NOW
PAST BFD AND JST.
PREV...
630AM UPDATE...MINOR CHANGES TO HOURLY T/TD BASED ON CONSOBS AND
SMALL ADJUSTMENTS TO POPS GIVEN LATEST RADAR TRENDS...WHICH SHOW
SOME LCLY MOD RAINS MOVG ACRS THE SUSQ VLY. ALSO...ISSUED FLW FOR
THE SWATARA CREEK ABOVE MIDDLETOWN. ICE JAM EFFECTS APPARENTLY
CAUSED THE CREEK TO RISE VERY RAPIDLY ABV FS. SEE HYDRO SECTION
FOR DETAILS.
LARGE SCALE HEIGHT FALLS ASSOCD WITH LEADING SHORTWAVE TROUGH
STRETCHING FROM THE ERN GRT LKS/UPPER OH VLY SWD THRU THE TN VLY
WILL LIFT NEWD INTO NEW ENGLAND BY TONIGHT. THIS WILL PUSH THE
ATTENDANT SFC COLD FRONT...CURRENTLY MOVG ACRS WRN PA...EWD THRU
THE CWA BY THIS EVENING. NEAR TERM MODEL DATA INDICATES THE BEST
MSTR/PWATS AND THETA-E ADV HAS SHIFTED E OF THE AREA...BUT THERE
WILL BE SUFFICIENT LOW-LVL CONVERGENCE ASSOCD WITH A DEVELOPING
FRONTAL WAVE AND FAVORABLE JET DYNAMICS TO MAINTAIN PERIODS OF
MAINLY LGT RAIN. DAY 1 QPF AMTS ARE LESS THAN 0.25 INCH. A MIX OF
RAIN/SNOW IS POSSIBLE ON THE NW EDGE OF THE PCPN SHIELD AS BLYR
TEMPS BECOME MARGINALLY COLD OVER NW PA. THE PCPN WILL TAPER OFF
FROM WEST TO EAST INTO TONIGHT...WITH THE HIGHEST POPS OVER THE
ERN 1/3 OF THE CWA AFT 18Z.
RIDGING SFC/ALOFT BEHIND THE DEPARTING SYSTEM SHOULD PROVIDE A
MAINLY DRY OVERNIGHT PERIOD. THE NEXT BATCH OF SHORTWAVE ENERGY
AND ASSOCD HEIGHT FALLS CURRENTLY DIVING INTO THE NRN PLAINS WILL
AMPLIFY A CLOSED H5 LOW OVER THE GREAT LAKES BY EARLY WEDNESDAY.
THIS ENERGY WILL SUPPORT A RATHER POTENT CLIPPER LOW TRACKING EWD
ACRS LWR MI TO A MEAN POSITION/OCCLUSION INVOF LAKE HURON/SRN
ONTARIO BY 12Z WED. GUIDANCE SHOWS A RIBBON OF LGT PCPN ALONG THE
WRN SLOPES OF THE APPLCHNS WHERE OROGRAPHICS WILL BE A FACTOR.
ANOTHER SURGE OF COLDER AIR WILL MAKE FOR LGT SNOW WITH A COATING
POSSIBLE OVER THE HIGHER ELEVATIONS ALONG THE ALLEGHENY FRONT.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
AS THE PRIMARY PIECE OF SHORTWAVE ENERGY/CLOSED H5 LOW SHEARS AND
LIFTS NEWD INTO THE LWR LKS...THE REMAINDER OF THE UPPER TROUGH
DIGS EWD THRU THE DEEP SOUTH AND TAKES ON A NEG TILT INTO THE SERN
STATES. THE MODELS ARE STILL NOT IN AGREEMENT WITH THIS SYSTEM BUT
DIFFERENCES ARE MUCH SMALLER THAN IN PREVIOUS CYCLES. AT THIS
TIME...THE 00Z GFS IS DEFINITELY THE FASTEST WITH THIS UPPER TROF
WHICH IS AGAINST THE MULTI-DAY SPAGHETTI TRENDS WHICH HAVE
CONTINUED TO SHIFT TO THE SLOWER SIDE OF THE ENVELOPE. THE SPREAD
CONTINUES TO BUILD AS THE SYSTEM QUICKLY LIFTS UP THE EAST COAST
WITH JET-INDUCED COASTAL LOW DEVELOPMENT COMMENCING OVER THE
WESTERN ATLANTIC. BY 16/1200Z...THE ENSEMBLE LOW PLOTS SHOW A
LARGE AMOUNT OF UNCERTAINTY WITH SURFACE LOWS DEPICTED ANYWHERE
WITHIN A 1000 KM RADIUS. INTERESTINGLY...THE 00Z/12Z ECMWF ARE ON
THE FAR SOUTHERN EXTENT OF THE ENSEMBLE SPREAD WITH ITS ENSEMBLE
MEAN ESSENTIALLY IN THE CENTER OF THIS SPREAD. IN FACT...THE 00Z
ECMWF IS EVEN FURTHER SOUTH OF THE CLUSTERING WHICH MAKES IT SEEM
LIKE A SLOW OUTLIER. FWIW...TRENDS IN THE 00-06Z GFS/12-00Z GEFS
SEEM TO BE FAVORING A SLOWER SYSTEM WITH A MORE SRN LOW POSITION
AT 16/12Z...WHICH CLUSTERS REASONABLY WELL WITH THE 00Z ECMWF/CMC.
WHILE A CONVERGENCE OF SOLNS MAY BE STARTING TO EMERGE...WILL
EMPLOY A ENSEMBLE/CONSENSUS APPROACH TO A LOW CONFIDENCE FCST.
CONCERNING QPF POTENTIAL...IT APPEARS THERE WILL BE A QPF AXIS
JUST AHEAD OF THE SPLITTING TROUGH AXIS AND ASSOCD SFC COLD FRONT
OR NEAR/JUST E OF THE APPALACHIAN SPINE FROM THE MTNS OF WV/VA
NEWD INTO NERN PA. FOLLOWED WPC GUIDANCE FAIRLY CLOSELY GIVEN THE
UNCERTAINTY WHICH RESULTED IN A RELATIVELY NARROW SWATH OF VERY
LGT SNOW ACCUMS GENERALLY LESS THAN 1 INCH FROM THE S-CNTRL MTNS
INTO THE SRN POCONOS.
THE PATTERN NEARLY REPEATS ITSELF INTO DAY 3/THURS AS RIDGING SFC
AND ALOFT AGAIN GIVES WAY TO ANOTHER SIGNIFICANT UPPER TROUGH AND
BATCH OF SHORTWAVE ENERGY MOVG INTO THE GRT LKS. BY DAY 4/FRI THE
MODEL SPREAD IS CLEARLY EVIDENT...WITH THE GFS AND NAM
REPRESENTING THE TWO TIMING EXTREMES (GFS FASTEST/NAM SLOWEST).
THEREFORE WPC LEANED ON THE ECMWF WHICH HAS SOME BROAD SUPPORT
FROM THE CMC. THIS SYSTEM LOOKS A LITTLE MORE INTERESTING IN TERMS
OF QPF AND POTENTIAL SNOWAMT FRI NGT BUT CONFIDENCE IS EVEN LOWER
THAN ON DAYS 2-3.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
THE 14/00Z GFS-ECMWF CAMPS ARE COMPLETELY OUT OF PHASE BY
SATURDAY WITH THEIR RESPECTIVE SFC FEATURES...WHICH ONLY GETS
WORSE WITH TIME. DESPITE THIS...THERE REMAINS DECENT AGREEMENT ON
A LONGWAVE SIGNAL WITH SHORTWAVE ENERGY CONTINUING TO
MAINTAIN/OCCASIONALLY AMPLIFY A MEAN ERN TROUGH. THE 500MB FLOW
APPEARS TO BRIEFLY FLATTEN OUT INTO EARLY NEXT WEEK WITH ONE OR
TWO CLIPPERS STREAKING BY TO THE NORTH. A MORE VIGOROUS TROUGH IS
PROJECTED INTO THE MIDDLE OF NEXT WEEK...ACCOMPANIED BY COLDER
TEMPS.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
LIGHT RAIN SHOWERS CONTINUE TO STREAM THROUGH CENTRAL
PENNSYLVANIA THIS MORNING. SO FAR THE RAIN AND FOG HAVE NOT BEEN
VERY DETRIMENTAL TO THE VISBYS BUT FOR ONLY A SHORT TIME AT JST.
EXPECT ANY IFR CIGS TO SLOWLY RISE AND THE OTHERWISE MVFR CIGS
AND VSBYS TO CONTINUE THROUGH 18Z FOR ALL TAF SITES. SHOWERS WILL
LAST WELL INTO MID DAY IN EASTERN AREAS...WHILE ENDING DURING THE
MID/LATE MORNING IN THE WEST. BFD SHOULD BE PRETTY MUCH FINISHED
WITH PRECIP FOR THE DAY.
BRIEF RIDGING VISITS TONIGHT INTO EARLY WEDNESDAY...BEFORE THE
NEXT WEAK FRONT SWEEPS IN FROM THE WEST. THIS WILL PROBABLY WILL
ALLOW CENTRAL AND EASTERN AREAS TO REMAIN IN VFR CONDITIONS...BUT
KEEP WESTERN MOUNTAIN IN MVFR CONDITIONS WITH LOWERED CIGS AND
SCATTERED SHOWERS. THE NIGHTTIME ARRIVAL OF THE PRECIP WILL
PROBABLY MAKE IT MORE SNOW THAN RAIN BUT A MIX IS EXPECTED.
OUTLOOK...
WED...MVFR CIGS/-SHRASN LIKELY W MTNS.
THU...NO SIG WX EXPECTED.
FRI...MVFR CIGS/-SHSN LIKELY W MTNS.
&&
.HYDROLOGY...
FLW STILL RUNNING FOR THE SWATARA CREEK ABOVE MIDDLETOWN. WHILE IT
HAS GONE BELOW FLOOD AND CAUTION STAGES FOR THE MOMENT...WILL KEEP
THE FLW GOING FOR JUST A BIT LONGER TO ALLOW FOR ANY REJUVINATION
OF THE CLOG DOWNSTREAM. BOTH HARRISBURG AND MIDDLETOWN GAGES ARE
CURRENTLY FALLING THOUGH.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/STEINBUGL
NEAR TERM...DANGELO/STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...DANGELO/CERU
HYDROLOGY...CTP
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
959 AM CST TUE JAN 14 2014
.DISCUSSION...
A NICE DAY UNDERWAY ACROSS THE MIDSOUTH AHEAD OF AN APPROACHING COLD
FRONT. SUNSHINE THIS MORNING COMBINED WITH A SOUTHERLY BREEZE IS
HELPING TEMPS WARM QUICKLY. CLOUDS IN ADVANCE OF THE FRONT ARE
STARTING TO MOVE INTO NE ARKANSAS AND WILL CONTINUE TO INCREASE
ACROSS THE REGION THIS AFTERNOON. SPOTTY LIGHT RAIN MAY MOVE INTO
NORTHERN AREAS THIS AFTERNOON AS THE FRONT PUSHES IN. LATEST
GUIDANCE INCLUDING THE HRRR KEEPS THIS PRECIP NORTH OF THE TN/MS
BORDER SO DECREASED POPS OVER PARTS OF NORTHEAST MS AND SE WEST TN
THIS AFTERNOON OTRW FORECAST LOOKS GREAT.
SJM
&&
PREV DISCUSSION... /ISSUED 450 AM CST TUE JAN 14 2014/
CURRENTLY...TEMPERATURES ARE IN THE LOW 30S IN THE NORTH WITH 40S
TO THE SOUTH. A FEW MORE DEGREES OF COOLING WILL TAKE PLACE
TONIGHT AS WINDS ARE LIGHT AND SKIES ARE CLEAR. A PROGRESSIVE
UPPER LEVEL PATTERN LOOKS TO CONTINUE FOR THE EASTERN HALF OF THE
US. THE COLD FRONT THAT AFFECTED US YESTERDAY HAS QUICKLY MOVED
OFF TO THE EAST COAST AND A NEW FRONTAL SYSTEM HAS ALREADY DROPPED
DOWN ACROSS THE HIGH PLAINS AND UPPER MIDWEST. THIS SYSTEM WILL
CONTINUE TO MOVE SOUTHEASTERLY AND APPROACH THE FORECAST AREA BY
LATE AFTERNOON TODAY.
SHORT TERM... TODAY THROUGH THURSDAY...
NORTHWEST FLOW ALOFT WILL DOMINATE THROUGH THE PERIOD AND SEND TWO
COLD FRONTS THROUGH THE MID-SOUTH IN LESS THAN 72 HOURS.TEMPERATURES
FOR TODAY SHOULD WARM RATHER QUICKLY UNDER MOSTLY CLEAR SKIES.
HIGHS ARE EXPECTED TO BE QUITE MILD ACROSS THE MID-SOUTH WITH
READINGS IN THE UPPER 50S TO NEAR 60. CLOUDS WILL BEGIN TO
INCREASE LATE THIS AFTERNOON...AHEAD OF THE AFOREMENTIONED COLD
FRONT. THE FRONT WILL MOVE THROUGH LATE AFTERNOON INTO EARLY EVENING
AND POSSIBLY SPAWN A FEW LIGHT SHOWERS ACROSS THE REGION. NNW WINDS
BEHIND THE FRONT WILL BE QUITE STRONG WITH SUSTAINED 10 TO 20 MPH
THIS EVENING AND TEMPERATURES WILL RAPIDLY COOL.
BEHIND THE FRONT...A FAIRLY STRONG LONGWAVE TROUGH WILL SWING
THROUGH THE MID-SOUTH OVERNIGHT TONIGHT. STRONG CAA AND DECENT LIFT WILL
LEAD TO THE POSSIBILITY OF LIGHT SNOW SHOWERS OR FLURRIES AFTER
MIDNIGHT...MAINLY EAST OF THE MISSISSIPPI RIVER. MOISTURE WILL BE
EXTREMELY LIMITED...SO NO ACCUMULATION IS EXPECTED...IN ADDITION
TO THE FACT OF THE GROUND BEING TOO WARM.
BEHIND THE FRONT...MUCH COOLER AIR...OF THE CANADIAN KIND WILL FUNNEL
INTO THE MID-SOUTH. HIGHS ON WEDNESDAY WILL MOSTLY BE IN THE 30S
TO AROUND 40 DURING THE DAYTIME. HOWEVER...THE AIRMASS WILL BECOME
QUICKLY MODIFIED BY THURSDAY AS SOUTHWESTERLY FLOW BECOMES
DOMINANT. THIS WARMUP WILL BE SHORT-LIVED AS WELL. ANOTHER STRONG
ARCTIC FRONT...ALSO LACKING ANY KIND OF REAL MOISTURE...WILL PUSH
THROUGH THE REGION ON THURSDAY NIGHT INTO FRIDAY. THIS AIRMASS
WILL BE SLIGHTLY COLDER AND DRIER THAN THE PREVIOUS ONE...WITH
HIGHS ONLY EXPECTED TO BE IN THE 30S DURING THE DAY OF FRIDAY.
LONG TERM...FRIDAY THROUGH EARLY NEXT WEEK...
FAIRLY QUIET WEEKEND WEATHER-WISE...AS HIGH PRESSURE WILL BE IN
CONTROL. MODEL GUIDANCE IS STILL IN DISAGREEMENT ABOUT HOW QUICKLY
THE AIRMASS WILL WARM THIS WEEKEND. NONETHELESS...TEMPERATURES WILL
BEGIN A SLOW WARMING TREND SATURDAY AND CONTINUE THROUGH MONDAY
WITH HIGHS NEAR NORMAL FOR THIS TIME OF YEAR.
LONG TERM MODEL GUIDANCE IS IN DECENT AGREEMENT THAT WE WILL HAVE
A SLIGHT BREAK FROM THIS PROGRESSIVE PATTERN AND FLOW ALOFT WILL
BECOME ZONAL THROUGH EARLY NEXT WEEK. AFTER THAT...MODELS ARE ONCE
AGAIN HINTING AT THE PROGRESSIVE PATTERN RETURNING BY MID TO LATE
WEEK NEXT WEEK.
AC3
&&
.AVIATION...
HIGH PRESSURE WILL SHIFT EAST TODAY AS SOUTHWESTERLY WINDS PICK UP
AT ALL TERMINALS THROUGH THIS AFTERNOON...AVERAGING BETWEEN 10-12
KTS SUSTAINED WITH GUSTS UP TO 20 KTS POSSIBLE. CLOUDS WILL
INCREASE AND LOWER AS A COLD FRONT MOVES ACROSS THE MID SOUTH.
ISOLATED SHOWERS CAN ALSO BE EXPECTED LATE THIS AFTERNOON AND
EVENING ALONG AND BEHIND THE FRONT. WINDS WILL ABRUPTLY SWITCH
NORTHWESTERLY BEHIND THE FRONT WITH GUSTS UP TO 20 KTS THROUGH THE
EVENING BEFORE DIMINISHING SLOWLY LATE TONIGHT. FRONTAL PASSAGE
SHOULD BE MID AFTERNOON AT KJBR...LATE AFTERNOON/EARLY EVENING AT
KMEM AND KMKL...AND THIS EVENING AT KTUP. CIGS SHOULD REMAIN VFR
EVEN WITH THE FRONTAL PASSAGE WITH SKIES CLEARING LATE TONIGHT
FROM WEST TO EAST.
JLH
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 58 29 40 29 / 20 20 10 0
MKL 57 27 37 22 / 20 20 10 0
JBR 55 27 39 26 / 20 10 10 0
TUP 60 30 41 24 / 10 20 10 0
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
249 AM PST Tue Jan 14 2014
.SYNOPSIS...
A much quieter weather pattern will continue to develop over the
Inland Northwest as a ridge of high pressure strengthens over the
Inland Northwest. While fairly benign weather is expected, areas
of fog will be possible each morning through the rest of the week.
&&
.DISCUSSION...
Today and Tonight...The Inland Northwest remains on the eastern
fringes of a building ridge, with northwest flow remaining for the
remainder of the day. Very light snow showers continue over the
highest elevations of the Idaho Panhandle, but little in the way
of accumulations are expected. Snow shower chances will remain for
the afternoon over these same locations as a shortwave rounds the
top of the ridge.
We continue to monitor the development of stratus and fog this
morning. The winds have calmed considerably over most locations
early this morning, but have remained up enough that fog and
stratus development has been delayed. Stratus has finally
developed over far eastern Washington and the Idaho Panhandle near
and north of I-90 (and moving westward). A quick look over area web
cams doesn`t show much in the way of fog, keeping most of it low
stratus so far. While patchy fog is possible this morning,
especially with winds becoming fairly light and the boundary layer
saturating, it might be a little too late for any fog of
significance. Better chances for fog will occur Tuesday night as
the ridge builds even further inland and temperature inversions
strengthen.
The thinking is that much less mixing combined with the cloud
cover will keep most areas cooler this afternoon than yesterday.
However, places like Omak, Wenatchee, and Moses lake will be on
the fringes of the cloud cover, so less cloud cover may lead to a
warmer forecast by a few degrees. ty
Wednesday through Saturday...Strong high pressure aloft will
dominate the Inland Northwest promoting strengthening temperature
inversions. Under the inversion expect increasing areas of stratus
and fog in the valleys while the mountains will be mostly clear
and mild for this time of year. Precise depth of stratus is where
the most uncertainty lies with GFS model soundings indicating the
potential for some break up of the stratus each afternoon and thus
forecast still calls for a 10-15 diurnal temperature swing between
low and high temperatures. However given the low January sun angle
and quite a bit of boundary layer moisture present its possible
that some areas will stay in the stratus all day and night. Where
this occurs expected actual conditions to be warmer than forecast
at night and cooler than forecast during the day making the
precise temperature forecast more uncertain. JW
Saturday night through Tuesday...Models in decent agreement that a
strong 500 mb ridge will remain parked over the region through
this period...however some guidance is still hinting at a weak
shortwave trough moving through ridge Saturday night/Sunday. The
ECMWF has backed off on this notion a bit from the previous run
and leaves the Canadian as the deepest outlier. Given the strength
of the longwave ridge...the drier solutions are most likely the
way to trend. We will keep some small pops in the forecast...but
given the weakening trend and swift easterly track most will
either be intercepted by the Cascade crest or the northern
mountains. Whether or not this system amounts to much...it will be
rapidly followed by more amplification of the ridge for a good
shot of dry weather into early next week as well as mild
temperatures (at least for the mountains). By Tuesday the model
consistency begins to falter as the ECMWF shows a potent shortwave
trough crossing the ridge while the GEM shows a much weaker
shortwave and the GFS shows barely a ripple of a disturbance
tracking through central BC. Since that is so far out into the
forecast...we will trend toward climatology across the far
northern zones...and keep the southern half of the forecast area
generally dry. Temperatures will remain tricky in the valleys as
high temperatures will depend on the ability to mix out any
inversions which are likely to form. Since winds in this pattern
are expected to be light...the mixing potential should be
low...especially if widespread stratus and fog is able to develop.
We will generally utilize a temperature forecast near or slightly
above normal in the valleys...and keep things well above normal
over the mountains. fx
&&
.AVIATION...
06Z TAFS: Main aviation impacts through 23z will be incr threat for
stratus along the WA/ID border then spreading west toward Moses
Lake. Models are overdoing the boundary layer moisture at this hour
so delayed the timing of stratus and also raised cigs frm previous
fcst based on obs vcnty KCOE. High Res HRRR does not support
restrictions anywhere in the forecast area but BUFKIT/MOS do and
opted to keep fcst trends this direction as winds decr near 10kts
and swing arnd to the S/SE. Following a short break in the stratus
Tue aftn...areas of low clouds and fg will return arnd 06z Wed. /sb
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 43 29 40 27 38 25 / 0 0 0 0 0 0
Coeur d`Alene 43 28 42 27 39 26 / 0 0 0 0 0 0
Pullman 47 31 44 31 44 30 / 0 0 0 0 0 0
Lewiston 50 30 47 30 44 30 / 0 0 0 0 0 0
Colville 39 28 37 25 36 24 / 0 0 0 0 0 0
Sandpoint 39 29 39 26 37 24 / 0 10 10 0 0 0
Kellogg 40 29 39 29 39 28 / 10 0 0 0 0 0
Moses Lake 48 25 44 25 42 23 / 0 0 0 0 0 0
Wenatchee 47 26 43 26 40 25 / 0 0 0 0 0 0
Omak 44 25 37 24 36 23 / 0 0 0 0 0 0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
553 AM CST TUE JAN 14 2014
.UPDATE...
ISSUED AT 553 AM CST TUE JAN 14 2014
HAVE REDUCED POP FORECASTS ACROSS NORTHEAST IOWA AND FAR SOUTHWEST
WISCONSIN...IN ACCORDANCE WITH THE 14.06Z NAM...14.08Z HRRR AND
RADAR TRENDS. WARM CONVEYOR BELT BAND OF SNOW HAS PROGRESSED
THROUGH ALMOST HALF OF THE FORECAST AREA...WITH THE DEFORMATION
BAND SITTING UP NORTH OF INTERSTATE 90. ALREADY SIGNS THAT THE
DEFORMATION BAND TRYING TO DROP SOUTH SOME ON MPX RADAR.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM CST TUE JAN 14 2014
AT 3 AM...A 998 MB SURFACE LOW WAS LOCATED JUST NORTH OF MANKATO
MINNESOTA. A BAND OF LIGHT RAIN EXTENDED SOUTH OF THIS LOW THROUGH
CENTRAL IOWA. MEANWHILE NORTH OF THIS LOW AND JUST EAST OF THERE
ARE REPORTS OF SNOW. VISIBILITIES HAVE BEEN REDUCED TO LESS THAN A
MILE NEAR ST CLOUD MINNESOTA. IN THE WAKE OF THIS LOW...THE WINDS
HAVE SHIFTED TO THE NORTHWEST AND INCREASED INTO THE 20 TO 30 MPH
RANGE. THERE ARE EVEN SOME WIND GUSTS UP TO 60 MPH ACROSS EASTERN
SOUTH DAKOTA.
THE 14.00Z MODELS ARE IN GOOD AGREEMENT THAT THIS SURFACE LOW WILL
MOVE EAST ALONG THE INTERSTATE 90 THIS MORNING...AND EAST TO
CENTRAL LAKE MICHIGAN BY 15.00Z. THIS IS A SLIGHTLY FURTHER NORTH
AND MUCH SLOWER TRACK THAN WHAT WAS SHOWN IN 13.00Z AND 13.12Z
MODEL RUNS. IN THE WAKE OF THIS LOW...A DEFORMATION BAND EXTENDS
WESTWARD ABOUT 300 MILES. DUE TO THIS...INCREASED PRECIPITATION
CHANCES SIGNIFICANTLY FOR THIS AFTERNOON ALONG AND NORTH OF
INTERSTATE 90. THIS LONGER DURATION MEANT THAT THE SNOW TOTALS
ALSO HAD TO BE INCREASED ALONG AND NORTH OF INTERSTATE 94. IT NOW
LOOKS LIKE THIS AREA WILL SEE SNOW TOTALS IN THE 5 TO 7 INCH
RANGE. AS A RESULT...UPGRADED THE CLARK..TAYLOR...JACKSON...
JUNEAU...AND ADAMS COUNTY TO A WINTER STORM WARNING. WE ALSO
EXTENDED THE END TIME OF THE WARNING AND ADVISORY IN WISCONSIN
BACK TO EITHER 15.00Z OR 15.06Z. ADAMS AND JUNEAU COUNTIES WILL
SEE THEIR WARNING EXTEND THE LONGEST TO THE DEFORMATION BAND
CONTINUING INTO THE EVENING.
WITH A STRONG FALL SURFACE PRESSURE COUPLET MOVING ACROSS
NORTHEAST IOWA THIS MORNING AND NORTHERN ILLINOIS THIS
AFTERNOON...EXPECT STRONG NORTHWEST WINDS 20 TO 30 MPH WITH WIND
GUSTS UP TO 45 MPH TO AFFECT SOUTHEAST MINNESOTA...NORTHEAST
IOWA...AND SOUTHWEST WISCONSIN TODAY. WITH THE COMBINATION OF
THESE WINDS AND 1 TO 3 INCHES OF SNOW WILL CAUSE SOME BLOWING AND
DRIFTING OF THE SNOW IN THESE AREAS. SINCE THE WINDS ARE SLOWER AT
SLACKENING...EXTENDED THE WINTER WEATHER ADVISORY FOR THESE AREAS
UNTIL 15.00Z. FURTHER NORTH THE WINDS WILL RANGE FROM 15 TO 30 MPH
FROM LATE THIS MORNING INTO THE AFTERNOON. THIS WILL CAUSE SOME
AREAS OF BLOWING AND DRIFTING ACROSS WEST CENTRAL...CENTRAL...AND
NORTH-CENTRAL WISCONSIN.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 348 AM CST TUE JAN 14 2014
ON WEDNESDAY NIGHT...ANOTHER SHORT WAVE TROUGH WILL MOVE QUICKLY
ACROSS THE REGION. WITH THE 15.00Z MODELS IN GOOD AGREEMENT WITH
PREVIOUS RUNS THAT SNOW WILL FALL ACROSS MUCH OF THE FORECAST
AREA...THE PRECIPITATION CHANCES WERE RAISED A BIT MORE. THE
HIGHEST CHANCES /UP TO 70 PERCENT/ WILL BE FOUND ALONG AND NORTH
OF THE INTERSTATE 94 CORRIDOR. THIS AREA WILL LIKELY SEE UP TO AN
INCH SNOW. MEANWHILE THE REMAINDER OF THE FORECAST AREA WILL
LIKELY SEE ANYWHERE FROM A TRACE TO AN INCH.
ON THURSDAY AND THURSDAY NIGHT...THERE CONTINUES TO BE SOME
TIMING DIFFERENCES WITH YET ANOTHER SHORT WAVE TROUGH. THE GFS IS
MUCH FASTER THAN EITHER THE NAM...GEM...OR ECMWF. SINCE THE GFS
LOOKS LIKE AN OUTLIER...TRENDED THE FORECAST TOWARD THE LATTER
MODELS. BEHIND THIS WAVE...STRONG COLD AIR ADVECTION IS EXPECTED
TO DEVELOP ACROSS THE AREA. IN ADDITION... THE TROPOPAUSE WILL
DROP DOWN TO 700 MB. THIS RESULTS IN RAPID INCREASE IN THE
PRESSURE FALLS IN THE WAKE OF THIS SYSTEM. DUE TO THIS...IT STILL
LOOKS LIKE THE NORTHWEST WINDS WILL INCREASE INTO THE 20 TO 30 MPH
RANGE AND THE WINDS WILL GUST TO 45 MPH DURING THE AFTERNOON AND
EVENING. THE STRONGEST WINDS WILL BE FOUND ACROSS NORTHEAST
IOWA...SOUTHEAST MINNESOTA...AND SOUTHWEST WISCONSIN.
ON FRIDAY MORNING...THE COMBINATION OF TEMPERATURES NEAR ZERO AND
NORTHWEST WINDS IN THE 15 TO 25 MPH RANGE WILL PRODUCE WINDS
CHILLS INTO THE -20 TO -25 RANGE ACROSS SOUTHEAST MINNESOTA AND
NORTHEAST IOWA. IF THIS TREND CONTINUES...A WINTER WEATHER
ADVISORY MAY BE NEEDED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 553 AM CST TUE JAN 14 2014
OVERALL THE SYSTEM THAT BROUGHT THE SNOW EARLY THIS MORNING HAS
SHIFTED A BIT FARTHER NORTH THAN PREVIOUSLY FORECAST. THIS RESULTS
IN LESS SNOW FOR THE TAF SITES OVERALL...BUT THE POTENTIAL FOR
SNOW REMAINS AND THE WINDS LOOK STRONGER. THIS MEANS MORE BLOWING
SNOW POTENTIAL. AN ADDITIONAL 1 TO 2 INCHES ARE EXPECTED TODAY.
VISIBILITIES SHOULD CLIMB FROM IFR TO MVFR IN THE NEXT HOUR OR TWO
AT BOTH TAF SITES...THEN REMAIN NEAR THERE THROUGH THE MORNING.
THEN SNOW OVER THE TWIN CITIES LOOKS TO DROP DOWN OVER THE TAF
SITES EARLY THIS AFTERNOON...REDUCING VISIBILITIES BACK DOWN TO
IFR. THE WHOLE SNOW AREA SHOULD PULL OUT BETWEEN 22-23Z...ALLOWING
VISIBILITIES TO IMPROVE. THE IMPROVEMENT SHOULD BE SOMEWHAT SLOWED
DOWN BY BLOWING SNOW...BUT THINK BY 01-02Z VISIBILITIES WILL HAVE
CLIMBED TO VFR. CEILINGS...ON THE OTHER HAND...LOOK TO CLIMB FROM
IFR/LIFR CURRENTLY TO MVFR BY NOON...THEN STAY THERE THROUGH 12Z
WEDNESDAY.
WINDS WILL RAPIDLY INCREASE THIS MORNING FROM THE NORTHWEST...
GUSTING TO 35 KT AT RST BY 13Z AND 30 KT AT LSE BY 16Z. WINDS WILL
DIMINISH THIS EVENING AS THE PRESSURE GRADIENT WEAKENS SOME.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR WIZ032-
033-041-042-053>055-061.
WINTER STORM WARNING UNTIL MIDNIGHT CST TONIGHT FOR WIZ043-044.
WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR WIZ017-029-
034.
MN...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ079-
086>088-094>096.
IA...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR
IAZ008>011-018-019-029-030.
&&
$$
UPDATE...AJ
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS ALBANY NY
104 PM EST TUE JAN 14 2014
.SYNOPSIS...
A FRONTAL BOUNDARY AND AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS
THE REGION THROUGH THIS AFTERNOON...BRINGING RAIN TO THE REGION.
A WEAK DISTURBANCE WILL BRING THE POSSIBILITY OF RAIN OR SNOW
SHOWERS TO THE REGION WEDNESDAY INTO WEDNESDAY NIGHT...ESPECIALLY
NORTH AND WEST OF ALBANY. SOMEWHAT COOLER TEMPERATURES WILL MOVE
INTO THE REGION FOR THE END OF THE WORKWEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1245 PM EST...LIGHT TO OCCASIONALLY MODERATE RAIN CONTINUES
ACROSS MUCH OF THE CWA...WITH SOME EMBEDDED BANDS OF HEAVIER RAIN
NOTED. THE LATEST RUC13 DEPICTS RATHER STRONG MID LEVEL 850-700 MB
FRONTOGENETICAL FORCING ACROSS THE REGION TO THE N/W OF DEVELOPING
SFC WAVE ALONG THE NORTHERN MID ATLANTIC COAST. EXPECT PERIODS OF
RAIN TO PERSIST THROUGH LATE THIS AFTERNOON...GRADUALLY DECREASING
FROM NW TO SE BETWEEN 4 PM AND 8 PM. SO...FOR MOST AREAS FROM THE
CAPITAL REGION AND POINTS S AND E...THE RAIN SHOULD STILL BE
FALLING DURING THE BULK OF THE EVENING COMMUTE.
IT IS POSSIBLE THAT SOME WET SNOW MIXES IN ACROSS HIGHER
ELEVATIONS LATER THIS AFTERNOON BEFORE ENDING...BUT THE BOUNDARY
LAYER APPEARS TO WARM FOR VALLEY LOCALES TO CHANGE OVER TO
SNOW...DESPITE STRONG UPWARD VERTICAL MOTION WITHIN F-GEN BANDS.
TEMPS WILL LIKELY HOLD NEARLY STEADY THROUGH THIS AFTERNOON...OR
MAY FALL A FEW DEGREES IN SOME AREAS...PARTICUALRLY HIGHER
ELEVATIONS. SO...MOST AREAS SHOULD REMAIN IN THE UPPER 30S TO MID
40S...WITH SOME TEMPS FALLING INTO THE MID 30S ACROSS HIGHER
ELEVATIONS ACROSS THE ADIRONDACKS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
ANY LEFTOVER PCPN WILL END EARLY TONIGHT...WITH DRY AND PARTLY
CLOUDY CONDITIONS FOR THE REST OF THE NIGHT. LOWS ARE FORECAST TO BE
IN THE 20S...BUT IF ENOUGH CLOUDINESS LINGERS THROUGH THE NIGHT...
THEN EXPECT TEMPS TO BE 3 TO 5 DEGREES HIGHER THAN FORECAST.
ON WEDNESDAY ANOTHER WEAK DISTURBANCE WILL SLOWLY APPROACH FROM THE
WEST. THIS DISTURBANCE WILL BE SO SLOW MOVING THAT THE THREAT OF
RAIN/SNOW SHOWERS FROM IT WILL PERSIST THROUGH WEDNESDAY NIGHT. THE
SYSTEM WILL BE WEAKENING AS IT APPROACHES WITH THE BEST FORCING
OCCURRING NORTH AND WEST OF THE FORECAST AREA. AS A RESULT...WILL
ONLY BE FORECASTING 20 TO 40 PERCENT CHANCE POPS DURING THE
PERIOD...WITH THE HIGHEST POPS OVER THE ADIRONDACKS. THE POPS WILL
DECREASE FURTHER TO ONLY 20 TO 30 PERCENT ON THURSDAY.
HIGHS WEDNESDAY WILL BE IN THE UPPER 30S AND 40S ONCE AGAIN. LOWS
WEDNESDAY NIGHT IN THE 20S...THEN HIGHS THURSDAY IN THE 30S TO LOWER
40S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
MUCH OF THE LONG TERM PORTION OF THE FORECAST LOOKS TO FEATURE A
RATHER CHAOTIC PATTERN WITH LOW PREDICTABILITY.
THE PERIOD STARTS OUT THURSDAY NIGHT INTO FRIDAY WITH AN AMPLIFIED
UPPER LEVEL PATTERN IN PLACE...WITH A DEEP TROUGH OVER THE GREAT
LAKES...MIDWEST AND MISSISSIPPI RIVER VALLEY WHILE A SOUTHWEST FLOW
ALOFT REMAINS ALONG THE EASTERN SEABOARD. DURING THIS TIME ONLY
SUBTLE DISTURBANCES AND SURFACE TROUGHS MAY IMPACT OUR AREA...WITH
THE CORE OF THE COLD AIR ALOFT REMAINING TO OUR WEST. THIS PATTERN
SHOULD RESULT IN A SLIGHT TO LOW CHANCE OF SNOW SHOWERS ALTHOUGH
NEAR SURFACE TEMPS LOOKS WARM ENOUGH FOR RAIN IN VALLEY LOCATIONS
DURING THE DAYLIGHT HOURS FRIDAY.
SOME GRADUAL COOLING THROUGH THE COLUMN OCCURS FRIDAY NIGHT...AS THE
UPPER TROUGH PROGRESSES EASTWARD. HOWEVER...OUR REGION LOOKS TO
ESCAPE ANY BITTER COLD WHICH SHOULD REMAIN NORTH OF THE REGION IN
CANADA. THE PRECIPITATION FORECAST FOR FRIDAY NIGHT INTO SATURDAY
LOOKS MURKY AT BEST. WITH SEVERAL PIECES OF ENERGY ROTATING AROUND
THE PERIPHERY OF THE DEEP TROUGH BEING CARVED OUT OVER THE EASTERN
CONUS...THERE WILL BE THE POTENTIAL FOR COASTAL CYCLOGENESIS TO
OCCUR DURING THIS TIME. MODELS DEPICTING VASTLY DIFFERENT SOLUTIONS
THOUGH...AS THE UPPER PATTERN REMAINS CHAOTIC. IF THE TROUGH BECOMES
NEGATIVELY TILTED LIKE THE ECMWF IS IMPLYING...THIS WOULD FAVOR
COASTAL DEVELOPMENT. HOWEVER...THE GFS IS SHOWING A POSITIVELY
TILTED TROUGH AND IS MORE PROGRESSIVE. THE GGEM LIES SOMEWHERE IN
BETWEEN DEPICTING MORE OF A NEUTRAL TILT. BOTTOM LINE IS THERE IS
TOO MUCH UNCERTAINTY TO RULE OUT ANY SCENARIO THIS FAR OUT SO WILL
MENTION CHANCE POPS FOR SNOW.
TEMPERATURES SHOULD COOL DOWN TO NEAR SEASONABLE LEVELS THROUGHOUT
THE REMAINDER OF THE WEEKEND...BUT NOT TO THE FRIGID READINGS THE
MODELS WERE IMPLYING THE PAST FEW DAYS. WHILE STILL REMAINING IN A
MEAN UPPER TROUGH...THE TROUGH IS NOW EXPECTED TO BE FLATTER AND
LESS AMPLIFIED...WHICH WOULD KEEP THE REALLY COLD AIR BOTTLED UP
NORTH OF THE REGION. THERE ARE SIGNS THAT FURTHER DEEPENING OF THE
TROUGH COULD OCCUR EARLY TO MID NEXT WEEK...BUT THIS IS UNCERTAIN AS
WELL.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
LIGHT RAIN WILL CONTINUE ACROSS THE AREA TODAY...AHEAD OF AND
ALONG A COLD FRONT AND WEAK LOW PRESSURE SYSTEM MOVING THROUGH.
CONDITIONS HAVE BEEN SLOW TO DETERIORATE THIS MORNING...AS
SATURATION HAS BEEN GRADUAL. EXPECTING CONDITIONS TO LOWER TO
MVFR...WITH THE POTENTIAL FOR OCCASIONAL IFR AS WELL BY 15Z-18Z.
WILL MENTION IFR IN TEMPOS. RAIN SHOULD END AROUND 23Z-24Z...AS
THE SYSTEM PULLS AWAY. WINDS WILL SHIFT TO THE NORTHWEST THIS
EVENING...BUT WILL BECOME NEAR CALM DURING THE OVERNIGHT. AT LEAST
PARTIAL CLEARING IS EXPECTED TO OCCUR...SO THERE WILL BE POTENTIAL
FOR FOG FORMATION DUE TO RESIDUAL LOW LEVEL MOISTURE FROM THE
RAINFALL.
SURFACE WINDS WILL INITIALLY BE SOUTHERLY AROUND 3-9 KT...THEN
DECREASE TO 3-5 KT FOR MUCH OF THE DAY AS WEAK LOW PRESSURE MOVES
ACROSS THE AREA WITH A VARIABLE DIRECTION THIS AFTERNOON.
NORTHWEST WINDS WILL DEVELOP THIS EVENING...BUT WILL BECOME NEAR
CALM OVERNIGHT INTO EARLY WEDNESDAY MORNING.
OUTLOOK...
WEDNESDAY TO THURSDAY: LOW OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
THURSDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
FRIDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...SHSN.
FRIDAY NIGHT TO SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
&&
.HYDROLOGY...
ICE JAM MOVEMENT HAS OCCURRED AT SCHENECTADY AND ALONG THE HOOSICK
RIVER NEAR BUSKIRK. RIVER LEVELS HAVE TRENDED DOWNWARD AS THE ICE
MOVES DOWNSTREAM AND BREAKS UP...SO NO FLOOD WARNINGS OR ADVISORIES
ARE IN EFFECT AT THIS TIME.
A UPPER LEVEL DISTURBANCE AND ASSOCIATED FRONTAL BOUNDARY WILL BRING
MAINLY LIGHT RAINFALL TO THE REGION THROUGH MOST OF TODAY. FORECAST
QPF GENERALLY RANGES FROM ONE QUARTER TO ONE HALF OF AN INCH. THESE
RAINFALL AMTS ARE NOT EXPECTED TO HAVE SIGNIFICANT EFFECTS ON
RIVERS/STREAMS AT THIS TIME.
MORE WEAK DISTURBANCES ARE POSSIBLE WED THROUGH THE END OF THE WEEK.
THESE WILL BRING A MIX OF RAIN AND SNOW...BUT ONCE AGAIN...AMOUNTS
WILL BE LIGHT AND HAVE LITTLE IF ANY IMPACT ON OUR HSA.
TEMPERATURES WILL REMAIN ABOVE NORMAL FOR THE BALANCE OF THE
WORKWEEK...THEN TURN COLDER THIS WEEKEND AT WHICH TIME ICE MAY AGAIN
BEGIN TO FORM ON ALL RIVERS AND STREAMS ACROSS THE REGION.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...GJM
NEAR TERM...KL/GJM/NAS
SHORT TERM...GJM
LONG TERM...JPV
AVIATION...NAS/JPV
HYDROLOGY...KL/GJM
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1256 PM EST TUE JAN 14 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE EAST OF THE TRI-STATE AREA BY THIS
EVENING. A WAVE OF LOW PRESSURE WILL DEVELOP ON THE FRONT JUST OFF
THE MID ATLANTIC COAST LATER TODAY AND PASS EAST OF LONG ISLAND
THIS EVENING. WEAK HIGH PRESSURE BRIEFLY BUILDS IN BEHIND THE
SYSTEM TONIGHT AND WEDNESDAY. MULTIPLE LOWS IMPACT THE NORTHEAST
THE SECOND HALF OF THE WEEK THROUGH THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MINOR CHANGES THIS UPDATE TO REFLECT THE LATEST TRENDS IN
OBSERVATIONS AND GUIDANCE. FORECAST APPEARS ON TRACK.
REGION CURRENTLY IN...AND FORECAST TO BE UNDER RIGHT REAR QUADRANT
OF 170+ KT 250 HPA JET THROUGH THIS AFTERNOON. BASED ON THIS
FORCING...AND MULTIPLE SHORTWAVES EVIDENT UPSTREAM IN WATER VAPOR
HAVE CONTINUED WITH CATEGORICAL POPS FOR REMAINDER OF DAY. COULD
SEE SOME LULLS IN BETWEEN SHORTWAVES...SO WENT WITH PERIODS OF
RAIN. WHILE SOME PATCHY FOG IS POSSIBLE...EXPECT ANY VISIBILITIES
TO GENERALLY BE AT OR ABOVE 3 MILES.
GIVEN CLOUD COVER AND PRECIPITATION...DO NOT EXPECT MUCH MOVEMENT
IN TEMPERATURE TODAY...SO HAVE UPDATED BASED UPON BLEND OF
LAV/MET/MAV GUIDANCE WITH NAM AND RUC 2-METER TEMPERATURES WHICH
REFLECT THIS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
FRONT IS EXPECTED TO CLEAR THE AREA EARLY THIS EVE...ALTHOUGH
THERE IS NO STRONG PUSH OF COLD AIR BEHIND IT SO CLEARING WILL BE
SLOW. THE LOW TRACKS INTO THE GULF OF MAINE THIS EVE AND THEN
CONTINUES THROUGH THE CANADIAN MARITIMES TONIGHT WITH WEAK RIDGING
BUILDING INTO THE REGION WED NIGHT.
EXPECT A CHILLY NIGHT WITH LIGHT WINDS AND MOSTLY CLEAR SKIES. NAM
MOISTURE PROFILES LOOK OVERDONE TONIGHT...ALTHOUGH THERE COULD BE
SOME PATCHY FOG AT OUTLYING LOCATIONS. LOWS IN THE MID TO UPPER
20S INLAND TO MID TO UPPER 30S IN METRO NY/NJ.
AS ONE PIECE OF UPPER ENERGY LIFTS OUT ANOTHER WILL DIVE THROUGH
THE PLAINS AND MIDWEST RE-AMPLIFYING THE UPPER TROUGH. AT THE
SFC...WEAK LOW PRES WILL TRACK THROUGH THE GREAT LAKES INTO SE
CANADA ON WED WITH A WEAK COLD FRONT APPROACHING THE AREA. DRY
WEATHER SHOULD HOLD THROUGH THE DAY.
HIGHS ON WED ARE TRICKY AS THE NAM WANTS TO DEVELOP STRATUS ON A
S-SE FLOW...WHILE THE GFS IS NOT AS PESSIMISTIC WITH A SW FLOW.
HAVE LEANED TOWARDS THE MORE OPTIMISTIC AND WARMER GFS FOR THE
TIME BEING.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
UNCERTAINTY REMAINS IN THE EXTENDED PERIOD WITH THE MODELS HANDLING
OF THE EVOLUTION OF MULTIPLE LOW PRESSURE SYSTEMS. PERIOD STARTS
OFF AND GENERALLY REMAINS UNDER A AMPLIFYING TROUGH...RESULTING IN A
EXTENDED THREAT OF UNSETTLED WEATHER WITH AN ABUNDANCE OF COASTAL
LOW FORMATIONS. COLD FRONT APPROACHES AND PASSES THROUGH THE REGION
LATE WED. FIRST ISSUE AT HAND IS A DEVELOPING COASTAL LOW WED NIGHT
INTO THURSDAY...WITH THE 00Z GFS BEING THE OUTLIER ON THE PLACEMENT
AND STRENGTH. GENERAL CONSENSUS WOULD LEND WITH THE LOW FORMING OFF
THE CAROLINA COAST BY THURS MORNING AS A POTENT SHORTWAVE ROUNDS THE
BASE OF THE TROUGH AND PUSHES OFFSHORE. THE LOW TREKS TO THE
NORTHEAST THURSDAY...PASSING EAST OF THE 40/70 BENCHMARK AROUND 00Z
FRI. 00Z NAM/CMC DEVELOP A MUCH DEEPER LOW...WITH THE GFS AND ECMWF
BOTH SHOWING THE ASSOCIATED UPPER LEVEL ENERGY WEAKENING DURING THE
DAY. AS SUCH...SOME QUESTION AS TO HOW FAR WEST THE PRECIPITATION
PUSHES THURS. WENT AHEAD AND CONTINUE SLIGHT CHANCE POPS LATE WED
NIGHT...THEN MAINTAINING SLIGHT CHANCE OVER WESTERN AREAS...AND
CHANCE POPS EASTERN LONG ISLAND AND INTO CT. LATEST MODEL RUNS DO
SUGGEST THE DEVELOPMENT OF AN INVERTED TROUGH ALONG THE
LOW...WHICH COULD INCREASE THE COVERAGE OF THE PRECIPITATION
FURTHER WEST. PRECIPITATION SHOULD THEN TAPER OFF WEST TO EAST BY
THURS NIGHT.
DRY WEATHER IN PLACE LATE THURS THROUGH FRIDAY AS THE REGION SITS
BETWEEN THE DEPARTING LOW AND THE NEXT APPROACHING LOW MOVING
THROUGH THE GREAT LAKES AS WEAK HIGH PRESSURE ATTEMPTS TO NUDGE IN.
THE LATTER LOW WILL PLAY THE PART IN BRINGING THE NEXT CHANCE OF
PRECIPITATION FRI NIGHT THROUGH SATURDAY AS IT DRAGS A COLD FRONT
THROUGH THE REGION. AS THE FRONT PUSHES OFFSHORE...ONCE AGAIN THE
MODELS DEVELOP A COASTAL LOW ALONG THE FRONT WITH THE FIRST
SHORTWAVE ENERGY FRI NIGHT. AS A SECOND...STRONGER SHORTWAVE
ROUNDS THE TROUGH...EXPECTING A MUCH DEEPER DEVELOPMENT OF THE
COASTAL LOW SAT-SAT NIGHT THAN WAS SEEN WITH THE COASTAL LOW
EARLIER IN THE WEEK. GFS...AS IT TENDS TO BE...IS MORE PROGRESSIVE
IN MOVING THE LOW TO THE NORTHEAST...THUS ALLOWING FOR MOST OF ITS
DEEPENING TO OCCUR TO THE NORTH OF THE AREA...WITH MINIMAL IMPACT.
ECMWF AND CMC LAG A BIT MORE...SUGGESTING THE PRECIPITATION WILL
LINGER INTO SAT EVENING. FOR NOW...WILL CAP WITH CHANCE
POPS...THOUGH THIS IS INCREASING CONFIDENCE OF SEEING
PRECIPITATION SAT...WITH THE TIMING THE UNKNOWN FACTOR.
THE PASSING OF ANOTHER SHORTWAVE AND SURFACE LOW COULD BRING ANOTHER
SHOT OF PRECIPITATION SUNDAY...WITH EVEN THEN ANOTHER CLIPPER
POSSIBLE MONDAY. HOWEVER...THERE IS SOME SUGGESTION OF A MORE
ZONAL FLOW BY MONDAY THAT COULD KEEP THE MAIN ENERGY/FORCING TO
THE NORTH...AND THUS KEEP ANY PRECIPITATION TO THE NORTH.
TEMPS GENERALLY ABOVE NORMAL FOR THE SECOND HALF OF THE WEEK. THE
COLD FRONT THIS WEEKEND SHOULD FINALLY USHER IN A MUCH COLDER
AIRMASS AS THE TROUGH ALOFT DEEPENS. TEMPS THEN HOVER NEAR NORMAL
THROUGH THE WEEKEND INTO NEXT WEEK. SIDED WITH A BLEND OF ECE/WPC
FOR TEMPS THROUGH THE EXTENDED.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
RAIN CONTINUES THROUGH THIS EVENING. TERMINALS NEAR THE COASTS MAY
HAVE CONDS DROP TO LIFR FROM TIME TO TIME WHEN THE RAIN LETS UP.
OTHERWISE...MVFR/IFR UNTIL RAIN TAPERS OFF FROM WEST TO EAST
BETWEEN 01Z-04Z.
SKIES CLEAR OUT AFTER RAIN ENDS. WINDS BECOME LIGHT...AND WITHOUT
A SURGE OF COOLER/DRYER AIR INTO THE REGION...CAN EXPECT PATCHY
FOG TO DEVELOP LATE TONIGHT AND INTO WEDNESDAY MORNING. WILL TEMPO
MVFR/IFR FOG FOR NOW DUE TO UNCERTAINTY.
SOUTH WINDS BECOME W/NW GOING INTO THE EVENING...THEN WILL BACK TO
THE S WEDNESDAY MORNING. WIND SPEEDS WILL BE LESS THAN 10 KT.
...NY METRO ENHANCED AVIATION WEATHER SUPPORT...
KJFK FCSTER COMMENTS: AMDS LIKELY. OCNL LIFR CIGS INTO THIS
EVENING. OTHERWISE...IFR CONDS IN RAIN...IMPROVING LATE.
KLGA FCSTER COMMENTS: AMDS LIKELY. CONDS WILL FLUCTUATE BETWEEN
MVFR/IFR THROUGH THIS EVENING IN RAIN...IMPROVING LATE.
KEWR FCSTER COMMENTS: AMDS LIKELY. CONDS WILL FLUCTUATE BETWEEN
MVFR/IFR THROUGH THIS EVENING IN RAIN...IMPROVING LATE.
KTEB FCSTER COMMENTS: AMDS LIKELY. CONDS WILL FLUCTUATE BETWEEN
MVFR/IFR THROUGH THIS EVENING IN RAIN...IMPROVING LATE.
KHPN FCSTER COMMENTS: AMDS LIKELY. OCNL LIFR CONDS INTO THIS
EVENING. OTHERWISE...IFR CONDS IN RAIN...IMPROVING LATE.
KISP FCSTER COMMENTS: AMDS LIKELY. OCNL LIFR CONDS INTO THIS
EVENING. OTHERWISE...IFR CONDS IN RAIN...IMPROVING LATE.
OUTLOOK FOR 18Z WEDNESDAY THROUGH SUNDAY...
.WEDNESDAY AFTERNOON...VFR.
.WEDNESDAY NIGHT...SLIGHT CHANCE OF PRECIPITATION...WINTRY MIX N/W
OF NYC TERMINALS...RAIN ELSEWHERE. MVFR OR LOWER POSSIBLE.
.THURSDAY-THURSDAY EVENING...PERIODS OF MVFR OR LOWER AND MIXED
PRECIPITATION POSSIBLE. TIMING UNCERTAIN.
.LATE THURSDAY NIGHT-FRIDAY...MAINLY VFR.
.SATURDAY...MVFR OR LOWER POSSIBLE IN RAIN AND/OR SNOW. CHANCE
W-NW GUSTS 25 KT.
.SUNDAY...VFR. W-SW WINDS GUSTING 25-30 KT POSSIBLE.
&&
.MARINE...
MINOR CHANGES THIS UPDATE TO REFLECT THE LATEST TRENDS IN
OBSERVATIONS AND GUIDANCE. FORECAST APPEARS ON TRACK.
SEAS AT 44017 DOWN TO 4.3 FT FOR PAST FEW HOURS...WITH WINDS
EXPECTED TO CONTINUE TO SLOWLY DIMINISH AND ONLY SEEING 1.6 FT OF
SWELL UPSTREAM AT 44066...AND WAVEWATCH RUNNING 1 TO 2 FT TOO
HIGH...HAVE CANCELLED THE SCA FOR ANZ-350. FOR NOW HAVE LEFT 5 FT
SEAS IN THE FORECAST FOR TONIGHT...BUT CONFIDENCE IN OCCURRENCE IS
ONLY AROUND 50 PERCENT. LIKELY WILL LOWER SEAS TO 4 FT WITH
AFTERNOON UPDATE.
GENERALLY EXPECTING SUB-SCA WINDS ON ALL WATERS THROUGH FRIDAY.
DEPENDING ON THE EXACT TRACK OF EACH COASTAL LOW AND WHERE IT
DEPENDS THE MOST...COULD SEE GUSTS UP TO AROUND 25 KTS ON THE
OCEAN WATERS FORM. THE COMBINATION OF COLD AIR ADVECTION AND A
TIGHTENING PRESSURE GRADIENT WITH THE PASSAGE OF THE COLD
FRONT...FOLLOWED BY THE COASTAL LOW SHOULD PRODUCE GUSTS TO AT
LEAST 25-30 KTS SAT INTO MON. GALES MAY BE POSSIBLE AS WELL SAT-
SUN ON THE OCEAN WATERS.
SEAS REMAIN ELEVATED THROUGH THE PERIOD...WITH AT LEAST 5 FT
EXPECTED ON THE OCEAN WATERS WED THROUGH THE WEEKEND. COULD SEE
SEAS BUILD 6-9 FT OVER THE WEEKEND AS WELL WITH THE INCREASING
WIND FLOW.
&&
.HYDROLOGY...
GENERALLY LOOKING AT 0.25 TO 0.50 INCHES OF RAINFALL ON TUE...BUT
PERHAPS AS MUCH AS AROUND 3/4 OF AN INCH ACROSS EASTERN LI/SE CT.
WHILE THIS WILL NOT GENERATE ANY FLOOD THREATS...THE POTENTIAL
STILL EXISTS FOR FLOODING DUE TO ICE JAMS. ANY OBSERVED OR
REPORTED ICE JAM DEVELOPMENT MAY WARRANT THE ISSUANCE OF A FLOOD
WARNING WITH LITTLE NOTICE.
&&
.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...NONE.
&&
$$
SYNOPSIS...24/SEARS
NEAR TERM...MALOIT
SHORT TERM...24
LONG TERM...SEARS
AVIATION...MPS
MARINE...24/MALOIT/SEARS
HYDROLOGY...24/MALOIT
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1140 AM EST TUE JAN 14 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE EAST OF THE TRI-STATE AREA BY THIS
EVENING. A WAVE OF LOW PRESSURE WILL DEVELOP ON THE FRONT JUST OFF
THE MID ATLANTIC COAST LATER TODAY AND PASS EAST OF LONG ISLAND
THIS EVENING. WEAK HIGH PRESSURE BRIEFLY BUILDS IN BEHIND THE
SYSTEM TONIGHT AND WEDNESDAY. MULTIPLE LOWS IMPACT THE NORTHEAST
THE SECOND HALF OF THE WEEK THROUGH THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MINOR CHANGES THIS UPDATE TO REFLECT THE LATEST TRENDS IN
OBSERVATIONS AND GUIDANCE. FORECAST APPEARS ON TRACK.
REGION CURRENTLY IN...AND FORECAST TO BE UNDER RIGHT REAR QUADRANT
OF 170+ KT 250 HPA JET THROUGH THIS AFTERNOON. BASED ON THIS
FORCING...AND MULTIPLE SHORTWAVES EVIDENT UPSTREAM IN WATER VAPOR
HAVE CONTINUED WITH CATEGORICAL POPS FOR REMAINDER OF DAY. COULD
SEE SOME LULLS IN BETWEEN SHORTWAVES...SO WENT WITH PERIODS OF
RAIN. WHILE SOME PATCHY FOG IS POSSIBLE...EXPECT ANY VISIBILITIES
TO GENERALLY BE AT OR ABOVE 3 MILES.
GIVEN CLOUD COVER AND PRECIPITATION...DO NOT EXPECT MUCH MOVEMENT
IN TEMPERATURE TODAY...SO HAVE UPDATED BASED UPON BLEND OF
LAV/MET/MAV GUIDANCE WITH NAM AND RUC 2-METER TEMPERATURES WHICH
REFLECT THIS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
FRONT IS EXPECTED TO CLEAR THE AREA EARLY THIS EVE...ALTHOUGH
THERE IS NO STRONG PUSH OF COLD AIR BEHIND IT SO CLEARING WILL BE
SLOW. THE LOW TRACKS INTO THE GULF OF MAINE THIS EVE AND THEN
CONTINUES THROUGH THE CANADIAN MARITIMES TONIGHT WITH WEAK RIDGING
BUILDING INTO THE REGION WED NIGHT.
EXPECT A CHILLY NIGHT WITH LIGHT WINDS AND MOSTLY CLEAR SKIES. NAM
MOISTURE PROFILES LOOK OVERDONE TONIGHT...ALTHOUGH THERE COULD BE
SOME PATCHY FOG AT OUTLYING LOCATIONS. LOWS IN THE MID TO UPPER
20S INLAND TO MID TO UPPER 30S IN METRO NY/NJ.
AS ONE PIECE OF UPPER ENERGY LIFTS OUT ANOTHER WILL DIVE THROUGH
THE PLAINS AND MIDWEST RE-AMPLIFYING THE UPPER TROUGH. AT THE
SFC...WEAK LOW PRES WILL TRACK THROUGH THE GREAT LAKES INTO SE
CANADA ON WED WITH A WEAK COLD FRONT APPROACHING THE AREA. DRY
WEATHER SHOULD HOLD THROUGH THE DAY.
HIGHS ON WED ARE TRICKY AS THE NAM WANTS TO DEVELOP STRATUS ON A
S-SE FLOW...WHILE THE GFS IS NOT AS PESSIMISTIC WITH A SW FLOW.
HAVE LEANED TOWARDS THE MORE OPTIMISTIC AND WARMER GFS FOR THE
TIME BEING.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
UNCERTAINTY REMAINS IN THE EXTENDED PERIOD WITH THE MODELS HANDLING
OF THE EVOLUTION OF MULTIPLE LOW PRESSURE SYSTEMS. PERIOD STARTS
OFF AND GENERALLY REMAINS UNDER A AMPLIFYING TROUGH...RESULTING IN A
EXTENDED THREAT OF UNSETTLED WEATHER WITH AN ABUNDANCE OF COASTAL
LOW FORMATIONS. COLD FRONT APPROACHES AND PASSES THROUGH THE REGION
LATE WED. FIRST ISSUE AT HAND IS A DEVELOPING COASTAL LOW WED NIGHT
INTO THURSDAY...WITH THE 00Z GFS BEING THE OUTLIER ON THE PLACEMENT
AND STRENGTH. GENERAL CONSENSUS WOULD LEND WITH THE LOW FORMING OFF
THE CAROLINA COAST BY THURS MORNING AS A POTENT SHORTWAVE ROUNDS THE
BASE OF THE TROUGH AND PUSHES OFFSHORE. THE LOW TREKS TO THE
NORTHEAST THURSDAY...PASSING EAST OF THE 40/70 BENCHMARK AROUND 00Z
FRI. 00Z NAM/CMC DEVELOP A MUCH DEEPER LOW...WITH THE GFS AND ECMWF
BOTH SHOWING THE ASSOCIATED UPPER LEVEL ENERGY WEAKENING DURING THE
DAY. AS SUCH...SOME QUESTION AS TO HOW FAR WEST THE PRECIPITATION
PUSHES THURS. WENT AHEAD AND CONTINUE SLIGHT CHANCE POPS LATE WED
NIGHT...THEN MAINTAINING SLIGHT CHANCE OVER WESTERN AREAS...AND
CHANCE POPS EASTERN LONG ISLAND AND INTO CT. LATEST MODEL RUNS DO
SUGGEST THE DEVELOPMENT OF AN INVERTED TROUGH ALONG THE
LOW...WHICH COULD INCREASE THE COVERAGE OF THE PRECIPITATION
FURTHER WEST. PRECIPITATION SHOULD THEN TAPER OFF WEST TO EAST BY
THURS NIGHT.
DRY WEATHER IN PLACE LATE THURS THROUGH FRIDAY AS THE REGION SITS
BETWEEN THE DEPARTING LOW AND THE NEXT APPROACHING LOW MOVING
THROUGH THE GREAT LAKES AS WEAK HIGH PRESSURE ATTEMPTS TO NUDGE IN.
THE LATTER LOW WILL PLAY THE PART IN BRINGING THE NEXT CHANCE OF
PRECIPITATION FRI NIGHT THROUGH SATURDAY AS IT DRAGS A COLD FRONT
THROUGH THE REGION. AS THE FRONT PUSHES OFFSHORE...ONCE AGAIN THE
MODELS DEVELOP A COASTAL LOW ALONG THE FRONT WITH THE FIRST
SHORTWAVE ENERGY FRI NIGHT. AS A SECOND...STRONGER SHORTWAVE
ROUNDS THE TROUGH...EXPECTING A MUCH DEEPER DEVELOPMENT OF THE
COASTAL LOW SAT-SAT NIGHT THAN WAS SEEN WITH THE COASTAL LOW
EARLIER IN THE WEEK. GFS...AS IT TENDS TO BE...IS MORE PROGRESSIVE
IN MOVING THE LOW TO THE NORTHEAST...THUS ALLOWING FOR MOST OF ITS
DEEPENING TO OCCUR TO THE NORTH OF THE AREA...WITH MINIMAL IMPACT.
ECMWF AND CMC LAG A BIT MORE...SUGGESTING THE PRECIPITATION WILL
LINGER INTO SAT EVENING. FOR NOW...WILL CAP WITH CHANCE
POPS...THOUGH THIS IS INCREASING CONFIDENCE OF SEEING
PRECIPITATION SAT...WITH THE TIMING THE UNKNOWN FACTOR.
THE PASSING OF ANOTHER SHORTWAVE AND SURFACE LOW COULD BRING ANOTHER
SHOT OF PRECIPITATION SUNDAY...WITH EVEN THEN ANOTHER CLIPPER
POSSIBLE MONDAY. HOWEVER...THERE IS SOME SUGGESTION OF A MORE
ZONAL FLOW BY MONDAY THAT COULD KEEP THE MAIN ENERGY/FORCING TO
THE NORTH...AND THUS KEEP ANY PRECIPITATION TO THE NORTH.
TEMPS GENERALLY ABOVE NORMAL FOR THE SECOND HALF OF THE WEEK. THE
COLD FRONT THIS WEEKEND SHOULD FINALLY USHER IN A MUCH COLDER
AIRMASS AS THE TROUGH ALOFT DEEPENS. TEMPS THEN HOVER NEAR NORMAL
THROUGH THE WEEKEND INTO NEXT WEEK. SIDED WITH A BLEND OF ECE/WPC
FOR TEMPS THROUGH THE EXTENDED.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
A COLD FRONT MOVES ACROSS THE AREA LATE THIS AFTERNOON INTO EARLY
THIS EVENING. VFR DETERIORATES TO MVFR/IFR/LIFR AHEAD OF IT WITH
STRATUS...FOG...AND RAIN MOVING IN ESPECIALLY IN THE TIME FRAME OF
MID MORNING THROUGH MID AFTERNOON...GENERALLY AROUND 15Z-22Z.
EXPECT SOME VARIABILITY AND FLUCTUATION OF CATEGORIES WITHIN THE
TIME FRAME FROM SITE TO SITE WITH AMENDMENTS LIKELY TO BETTER
REFINE TIMING OF THESE LOWER CONDITIONS.
CONDITIONS SHOULD IMPROVE SLIGHTLY TO MVFR LATE AFTERNOON AND
EVENING AS RAIN EVENTUALLY ENDS FROM WEST TO EAST. STRATUS SHOULD
SCATTER...WITH FOG LINGERING DUE TO LIGHT WINDS AND LINGERING
MOISTURE. WINDS GENERALLY 10 KTS OR LESS THROUGH THE PERIOD WITH
DIRECTION S-SW BECOMING W-NW TONIGHT BEHIND THE COLD FRONT. WINDS
BECOME LIGHTER AND VARIABLE IN DIRECTION LATE...TAKING A MORE
ONSHORE DIRECTION BY WED MORNING. BECAUSE OF THIS...THERE WILL BE
THE POTENTIAL FOR PATCHY FOG WITH MVFR CONDITIONS POSSIBLE.
OVERALL...CONFIDENCE IS HIGH WITH WIND SPEED FORECAST AND MODERATE
WITH THE WIND DIRECTION FORECAST. CONFIDENCE IS LOWER ON THE
CATEGORY FORECAST AS TIMING OF LOWERING CATEGORY COULD BE OFF BY
1-3 HOURS...LIKELY BEING LATER THAN FORECAST. IT IS POSSIBLE THAT
THE MINIMUM CATEGORIES TODAY COULD BE END UP BEING ONE LEVEL
HIGHER THAN FORECAST.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
KJFK FCSTER COMMENTS: AMENDMENTS LIKELY AS CONDITIONS COULD
FLUCTUATE TODAY. MVFR AND IFR MAY OCCUR 1-3 HRS LATER THAN
FORECAST.
KLGA FCSTER COMMENTS: AMENDMENTS LIKELY AS CONDITIONS COULD
FLUCTUATE TODAY. MVFR AND IFR MAY OCCUR 1-3 HRS LATER THAN
FORECAST.
KEWR FCSTER COMMENTS: AMENDMENTS LIKELY AS CONDITIONS COULD
FLUCTUATE TODAY. MVFR AND IFR MAY OCCUR 1-3 HRS LATER THAN
FORECAST.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: AMENDMENTS LIKELY AS CONDITIONS COULD
FLUCTUATE TODAY. MVFR AND IFR MAY OCCUR 1-3 HRS LATER THAN
FORECAST.
KHPN FCSTER COMMENTS: AMENDMENTS LIKELY AS CONDITIONS COULD
FLUCTUATE TODAY. IFR AND LIFR MAY OCCUR 1-3 HRS LATER THAN
FORECAST.
KISP FCSTER COMMENTS: AMENDMENTS LIKELY AS CONDITIONS COULD
FLUCTUATE TODAY. MVFR AND IFR MAY OCCUR 1-3 HRS LATER THAN
FORECAST.
OUTLOOK FOR 12Z WED THROUGH SAT...
.WED...POSSIBLE MVFR IN MORNING WITH PATCHY FOG...OTHERWISE VFR.
.WED NIGHT...SLIGHT CHANCE OF PRECIPITATION...WINTRY MIX N/W OF NYC
TERMINALS...RAIN ELSEWHERE. MVFR OR LOWER POSSIBLE.
.THU-THU EVE...PERIODS OF MVFR OR LOWER AND MIXED PRECIPITATION
POSSIBLE - TIMING UNCERTAIN.
.LATE THU NIGHT-FRI...MAINLY VFR.
.SAT...PERIODS OF SUB-VFR AND MIXED PRECIPITATION POSSIBLE - TIMING
UNCERTAIN. CHANCE W-NW GUSTS 25 KT.
&&
.MARINE...
MINOR CHANGES THIS UPDATE TO REFLECT THE LATEST TRENDS IN
OBSERVATIONS AND GUIDANCE. FORECAST APPEARS ON TRACK.
SEAS AT 44017 DOWN TO 4.3 FT FOR PAST FEW HOURS...WITH WINDS
EXPECTED TO CONTINUE TO SLOWLY DIMINISH AND ONLY SEEING 1.6 FT OF
SWELL UPSTREAM AT 44066...AND WAVEWATCH RUNNING 1 TO 2 FT TOO
HIGH...HAVE CANCELLED THE SCA FOR ANZ-350. FOR NOW HAVE LEFT 5 FT
SEAS IN THE FORECAST FOR TONIGHT...BUT CONFIDENCE IN OCCURRENCE IS
ONLY AROUND 50 PERCENT. LIKELY WILL LOWER SEAS TO 4 FT WITH
AFTERNOON UPDATE.
GENERALLY EXPECTING SUB-SCA WINDS ON ALL WATERS THROUGH FRIDAY.
DEPENDING ON THE EXACT TRACK OF EACH COASTAL LOW AND WHERE IT
DEPENDS THE MOST...COULD SEE GUSTS UP TO AROUND 25 KTS ON THE
OCEAN WATERS FORM. THE COMBINATION OF COLD AIR ADVECTION AND A
TIGHTENING PRESSURE GRADIENT WITH THE PASSAGE OF THE COLD
FRONT...FOLLOWED BY THE COASTAL LOW SHOULD PRODUCE GUSTS TO AT
LEAST 25-30 KTS SAT INTO MON. GALES MAY BE POSSIBLE AS WELL SAT-
SUN ON THE OCEAN WATERS.
SEAS REMAIN ELEVATED THROUGH THE PERIOD...WITH AT LEAST 5 FT
EXPECTED ON THE OCEAN WATERS WED THROUGH THE WEEKEND. COULD SEE
SEAS BUILD 6-9 FT OVER THE WEEKEND AS WELL WITH THE INCREASING
WIND FLOW.
&&
.HYDROLOGY...
GENERALLY LOOKING AT 0.25 TO 0.50 INCHES OF RAINFALL ON TUE...BUT
PERHAPS AS MUCH AS AROUND 3/4 OF AN INCH ACROSS EASTERN LI/SE CT.
WHILE THIS WILL NOT GENERATE ANY FLOOD THREATS...THE POTENTIAL
STILL EXISTS FOR FLOODING DUE TO ICE JAMS. ANY OBSERVED OR
REPORTED ICE JAM DEVELOPMENT MAY WARRANT THE ISSUANCE OF A FLOOD
WARNING WITH LITTLE NOTICE.
&&
.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...NONE.
&&
$$
SYNOPSIS...24/SEARS
NEAR TERM...MALOIT
SHORT TERM...24
LONG TERM...SEARS
AVIATION...MPS
MARINE...MALOIT/24/SEARS
HYDROLOGY...MALOIT/24
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS GRAY ME
236 PM EST TUE JAN 14 2014
.SYNOPSIS...
A SERIES OF WEAK LOW PRESSURE SYSTEMS WILL TRACK NORTHEAST ALONG
THE EASTERN SEABOARD THIS WEEK. EACH OF THESE LOWS PROVIDE A ROUND
OF MAINLY LIGHT PRECIPITATION...AND EACH ONE WILL ALSO BRING
WAVES OF COLDER AIR. THE FIRST SYSTEM CROSSED THE REGION TODAY...
BRINGING RAIN TO THE REGION. ANOTHER SYSTEM WILL BRUSH THE COAST
OF NEW ENGLAND ON THURSDAY. WE WILL SEE ANOTHER ONE DAY BREAK ON
FRIDAY...BEFORE ANOTHER SYSTEM MOVES IN SATURDAY. AN ALBERTA
CLIPPER WILL CROSS NEW ENGLAND ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
RAIN AND AREAS OF FOG WILL CONTINUE THROUGH THE EVENING HOURS.
FOR A PERIOD LATER THIS EVENING...THE RAIN MAY MIX WITH SNOW IN
THE MOUNTAINS. HOWEVER...THIS WILL BE A BRIEF PERIOD...AND WILL
ALL OF THE RAIN TODAY...WILL NOT BE INCLUDING ANY ACCUMULATING
SNOWFALL IN THE GRIDS.
LATEST HRRR RUN HAS THE PRECIP ENDING AROUND 03Z IN MOST
LOCATIONS. EXPECT AREAS OF FOG TO CONTINUE WITH PLENTY OF LOW
LEVEL MOISTURE FROM THE RECENT RAINS. DRIER AIR WILL SLOWLY FILTER
INTO THE REGION LATER TONIGHT AND WEDNESDAY MORNING.
TEMPERATURES WILL FALL BELOW FREEZING BY MORNING IN JUST ABOUT ALL
OF MAINE AND NEW HAMPSHIRE...SO THERE COULD BE SOME SLICK SPOTS
AND BLACK ICE FOR THE MORNING COMMUTE ON WEDNESDAY.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
WE WILL BE IN BETWEEN WEATHER SYSTEMS WEDNESDAY AND WEDNESDAY NIGHT
IN OUR FORECAST AREA. FIRST DISTURBANCE OVER THE EASTERN GREAT
LAKES WILL WEAKEN AND HEAD INTO CANADA ON WEDNESDAY. THIS MAY
BRING SCATTERED RAIN OR SNOW SHOWERS TO THE MOUNTAINS.
A SECOND AREA OF LOW PRESSURE WILL FORM OF THE SOUTHEASTERN U.S.
COASTLINE WEDNESDAY NIGHT. DURING THIS PERIOD...THE UPPER LEVEL
TROUGH WILL BEGIN TO HAVE A STRONG NEGATIVE TILT AS IT REORGANIZES
OFF THE SOUTH CAROLINA COASTLINE. MOST OF THE CLOUDINESS WILL
REMAIN OFF THE COAST...HOWEVER THIS MAY ALLOW FOR PATCHY LATE
NIGHT FOG TO FORM.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
WE BEGIN THE PERIOD WITH A DEEP TROUGH OVER THE EASTERN TWO-THIRDS OF
THE CONUS AND A WEST COAST RIDGE. A SERIES OF IMPULSES WILL DIVE
SOUTHEAST INTO THE UPPER TROUGH AND KEEP OUR WEATHER MILD BUT
UNSETTLED FOR THE SECOND HALF OF THE WORKWEEK. WHILE MODELS AGREE
THE UPPER TROUGH WILL EVENTUALLY SLIDE EAST AND DELIVER MUCH
COLDER AIR TO THE AREA FOR THE SECOND HALF OF THE WEEKEND...THERE
ARE SIGNIFICANT TIMING DIFFERENCES WITH INDIVIDUAL IMPULSES. BY
MONDAY...WE`RE LEFT WITH A BROAD TROUGH OVER THE EASTERN TWO
THIRDS OF THE CONUS AS THE CORE OF THE COLD AIR BEGINS TO LIFT OUT
TO OUR NORTH AND EAST. HOWEVER...THE NUMERICALS SUGGEST THE UPPER TROUGH
WILL ONCE AGAIN DEEPEN AND DELIVER A FRESH SHOT OF ARCTIC AIR TO THE
GREAT LAKES AND NEW ENGLAND BY THE MIDDLE OF NEXT WEEK.
IN THE DAILIES...LOW PRESSURE WILL DEVELOP OFF THE ATLANTIC COAST
ON THURSDAY THEN PASS WELL TO OUR SOUTH AND EAST THURSDAY NIGHT
FOLLOWED BY A WEAK RIDGE OF HIGH PRESSURE EARLY FRIDAY. ANOTHER
LOW WILL CROSS THE REGION FRIDAY NIGHT INTO SATURDAY. ANOTHER LOW
AND TRAILING COLD FRONT WILL MOVE SOUTHEAST...AND USHER MUCH
COLDER AIR INTO THE REGION FOR THE SECOND HALF OF THE HOLIDAY
WEEKEND.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
SHORT TERM...AREAS OF IFR WITH LOCALLY A FEW LOCATIONS WITH LIFR.
CONDITIONS SLOWLY IMPROVING TONIGHT INTO EARLY WEDNESDAY.
LONG TERM...
THU...SCT MVFR POSSIBLE IN RAIN OR SNOW SHOWERS.
FRI NIGHT - SAT...AREAS OF MVFR POSSIBLE IN RAIN OR SNOW.
NW SFC WND GUSTING TO 25 KT PSBL SAT.
&&
.MARINE...
SHORT TERM...SCAS REMAIN IN EFFECT FOR THE OUTER WATERS THROUGH WEDNESDAY...MAINLY
FOR SEAS...HOWEVER THERE WILL BE GUSTY WINDS EARLY THIS EVENING IN
THE WATERS OFF THE MIDCOAST.
LONG TERM...
SAT - SUN...SMALL CRAFT CONDITIONS ARE LIKELY.
&&
.HYDROLOGY...
THE SUGAR RIVER AT WEST CLAREMONT IS SITTING VERY CLOSE TO ITS
FLOOD STAGE. WILL LIKELY BE LOWERING THE WARNING FOR THIS RIVER
DURING THE EVENING HOURS.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 PM EST
WEDNESDAY FOR ANZ150-152-154.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
449 PM EST TUE JAN 14 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 359 PM EST TUE JAN 14 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD MID/UPPER LEVEL TROUGH
FROM HUDSON BAY INTO THE CNTRL CONUS. A POTENT SHORTWAVE TROUGH
LOCATED OVER SRN WI WAS MOVING TOWARD SRN LOWER MI. AT THE SFC
CIRCULATION AROUND A 999 MB LOW PRES OVER E CNTRL WI RESULTED IN
STRONG NE WINDS INTO SRN UPPER MI. INCREASING NRLY WINDS ACROSS LAKE
SUPERIOR ALONG WITH 850 MB TEMPS IN THE -13C TO -16C RANGE SUPPORTED
LIGHT LES FOR LOCATIONS FAVORED BY NNE WINDS. STRONG 700-500 MB
QVECTOR CONV AND FGEN (FN/FS CONV) NEAR THE SHRTWV PIVOT POINT HAS
PRODUCED HEAVY SNOWFALL RATES OF AN INCH OR TWO PER HOUR OVER FAR
SRN UPPER (MNM) MI WHERE 7 INCHES HAD FALLEN BY 20Z. THIS ALSO
ALIGNED WELL WITH THE SRN EXTENT OF THE COLDER CLOUD TOPS...PER IR
LOOP.
LATE THIS AFTERNOON AND TONIGHT...SATELLITE/RADAR TRENDS AND SHORT
RANGE MODELS SUGGEST THAT THE COMMA HEAD PORTION OF THE SHRTWV WILL
MOVE INTO LAKE MI THIS EVENING BTWN 00Z-03Z AND DRAG THE BACK END OF
THE SNOW OUT OF THE SRN CWA. UNTIL THEN...MODERATE TO HEAVY SNOW
WILL CONTINUE OVER THE SOUTH ALONG WITH NE WINDS GUSTING TO AROUND
30 MPH. EXPECT THE LES IN CONVERGENT NRLY FLOW INTO WRN ALGER COUNTY
TO INCREASE AS THE DEEPER MOISTURE WITH THE SYNOPTIC SYSTEM EDGES
SLOWLY NORTHWARD. ALTHOUGH THE DEEPER MOISTURE WILL DEPART AFT
06Z...INSTABILITY WILL INCREASE AS CAA DROPS 850 MB TEMPS TO AROUND
-17C. MODERATE SNOWFALL AMOUNTS IN THE 3 TO 5 INCH RANGE ARE
EXPECTED MAINLY NEAR AU TRAIN/EBEN/CHATHAM...PER CONSENSUS OF HIGHER
RES MODELS. OVER THE WEST...INVERSION HEIGHTS AROUND 3K FT SHOULD
LIMIT SNOW AMOUNTS TO LESS THAN AN INCH.
WED....MID/UPPER LEVEL RIDGING WILL DEVELOP OVER THE NRN LAKES AHEAD
OF THE NEXT SHRTWV DIVING TOWARD SRN MANITOBA AND NRN MN. AT THE
SURFACE...A RIDGE FROM MN INTO NW ONTARIO WILL BUILD TOWARD THE SRN
GREAT LAKES AS A DEEP CLIPPER LOW MOVES TO NEAR LAKE WINNIPEG.
THIS WILL LEAD TO NORTH-NORTHWEST WINDS ACROSS LAKE SUPERIOR AND
WITH 850MB TEMPS AROUND -16C THERE WILL BE ENOUGH LAKE INSTABILITY
AND LOW LEVEL MOISTURE FOR LINGERING LAKE EFFECT. BUT WITH THE
SURFACE RIDGE QUICKLY SLIDING THROUGH THE UPPER GREAT LAKES...EXPECT
WINDS TO QUICKLY BACK THROUGH THE DAY. THE BACKING WINDS...ALONG
WITH DRIER LOW LEVEL AIR WILL BRING AN END TO THE LAKE EFFECT OVER
THE WEST AROUND EARLY AFTERNOON AND THEN OVER THE EAST BY LATE
AFTERNOON.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 446 PM EST TUE JAN 14 2014
RIDGE WEST...TROUGH EAST. THE PATTERN REMAINS THROUGH THROUGH MUCH
OF THE LONG TERM PERIOD.
FOR AN OVERVIEW OF WHAT WILL BE HAPPENING ALOFT...THE 500MB LOW OVER
N MANITOBA AT 00Z THURSDAY WILL SWEEP INTO CENTRAL ONTARIO AND THE W
HALF OF LAKE SUPERIOR BY 12Z THURSDAY. AT THAT POINT THE LOW WILL
SLOW DOWN QUITE A BIT...AND REMAIN ACROSS THE UPPER GREAT LAKES
THROUGH THE DAY THURSDAY...BEFORE THE LINGERING TROUGH SLOWLY EXITS
ACROSS EASTERN ONTARIO AND LAKE HURON FRIDAY AND FRIDAY NIGHT. THIS
WILL KEEP NNW FLOW ALOFT ACROSS LAKE SUPERIOR AND UPPER MI FROM
FRIDAY AFTERNOON THROUGH SUNDAY MONDAY.
AS FOR SPECIFICS...THE SFC LOW NEAR THE S MANITOBA/ONTARIO BORDER
JUST PRIOR TO 06Z THURSDAY SHOULD SHIFT SE INTO S CENTRAL LAKE
SUPERIOR/AND THE W HALF OF UPPER MI BY 18Z. S-SSW WINDS WILL REMAIN
IN THE 10-20KT RANGE WEDNESDAY NIGHT. WARMER AIR WILL BE ABLE TO
SWEEP IN FOR THURSDAY...WITH HIGHS IN THE UPPER 20S...THANKS TO THE
MID AFTERNOON LOW PASSAGE ALLOWING 850MB TEMPS TO RISE INTO THE -5
TO -7F RANGE. EXPECT THE SFC LOW TO EXIT FAR E UPPER MI THURSDAY
NIGHT INTO FRIDAY. GIVEN THE SLOW PROGRESS OF THE LOW...LOOK FOR A
SIGNIFICANT BREAK BETWEEN THE STRONG W-SSW WINDS WEDNESDAY NIGHT AND
COLDER AIR RUSHING IN THE N-NNW WINDS THURSDAY NIGHT INTO FRIDAY.
HIGH FRIDAY SHOULD BE ON THE ORDER OF 15F COOLER OVER W AND CENTRAL
UPPER MI...WHILE ONLY A COULD DEGREES COOLER E.
ALTHOUGH FAR W LAKE SUPERIOR MAY BE PRETTY FROZEN...THERE IS LIKELY
PLENTY OF RELATIVELY WARM OPEN WATER STILL AVAILABLE N OF THE
APOSTLE ISLANDS TO ALLOW THE MAINLY N FLOW OF COLD AIR TO PRODUCE
MODERATE LES FROM LATE THURSDAY AFTERNOON THROUGH THE DAY FRIDAY.
THE FLOW BECOMES MORE W-NW OVER W LAKE SUPERIOR FRIDAY EVENING AS
WAA TAKES HOLD AND 850MB TEMPS THAT WERE ON THE ORDER OF -14 TO -17C
QUICKLY JUMP UP TO AROUND -10C. LES WILL CONTINUE TO PERSIST NEAR
AND E OF MUNISING INTO SATURDAY. THERE IS STILL A QUESTION AS TO HOW
LONG THE FETCH REMAINS FAVORABLE FOR THIS AREA...AS THE 12Z ECMWF IS
GOING WITH A MORE W FLOW NEAR THE SFC...WHICH WOULD KEEP THE BEST
CHANCE OF LES ONLY RIGHT ALONG THE SHORELINE E SATURDAY...IF NOT OFF
SHORE.
A SIZABLE RIDGE EXTENDING UP FROM THE 4-CORNERS REGION THROUGH THE
DAKOTAS AND SOUTH CENTRAL CANADA SUNDAY MORNING WILL BRIEFLY MOVE
ACROSS THE UPPER GREAT LAKES SUNDAY AFTERNOON INTO SUNDAY EVENING.
WHILE THE 12Z RUN OF THE GFS IS LESS THAN IMPRESSIVE WITH THE
RIDGE...THE 00Z RUNS OF THE ECMWF AND TO A GREATER EXTENT THE
CANADIAN MODEL.
OTHERWISE PAST SUNDAY EVENING WE GET BACK INTO THE PERSISTENT NW
FLOW AGAIN ALOFT...THANKS TO THE MAIN 500MB LOW SLIDING FROM N
CENTRAL CANADA FRIDAY NIGHT...ACROSS JAMES BAY SATURDAY NIGHT...AND
INTO QUEBEC SUNDAY/SUNDAY NIGHT. WHILE THE MAIN LOW RETREATS BACK
N...A MODERATED PIECE OF THE COLDER AIR WILL BE ABLE TO DIVE IN
MONDAY NIGHT THROUGH MUCH OF THE UPCOMING WORK WEEK /AT LEAST
ACCORDING TO THE 12Z ECMWF/. GIVEN THE PERSISTENT N-NNW FLOW...HAVE
INCREASED POPS FOR MONDAY NIGHT THROUGH TUESDAY ALONG LAKE SUPERIOR
TO LIKELY AND DEFINITE CATEGORIES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 109 PM EST TUE JAN 14 2014
LAKE EFFECT SNOW SHOWERS WILL CONTINUE INTO TONIGHT AND WED MORNING.
EXPECT MVFR CONDITIONS AT KCMX AND KIWD BUT CONDITIONS WILL LOWER
TO IFR AT KSAW BY MID AFTERNOON AND CONTINUE THROUGH MUCH OF TONIGHT
AS THERE IS MORE OF A POTENTIAL FOR MODERATE LAKE EFFECT SNOW AND
BLOWING SNOW AS NORTH WINDS INCREASE TO 15 TO 25 MPH BY THIS
EVENING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 359 PM EST TUE JAN 14 2014
NORTH WINDS OF 30 KNOTS OVER ERN LAKE SUPERIOR TONIGHT AS A SFC LOW
PASSES SOUTH AND EAST OF REGION WILL PRODUCE HEAVY FREEZING SPRAY.
EXPECT THE WINDS TO DIMINISH BRIEFLY ON WEDNESDAY AS A HIGH PRESSURE
RIDGE CROSSES THE REGION. LOW PRESSURE CROSSING LAKE WINNIPEG LATE
WEDNESDAY AFTERNOON WILL THEN SINK ACROSS LAKE SUPERIOR ON THURSDAY.
SW GALES OF 35 KTS ARE POSSIBLE WEDNESDAY NIGHT OVER EASTERN SECTIONS.
N-NW GALES OF 35 KTS ARE ALSO POSSIBLE LATE THURSDAY AFTERNOON THROUGH
FRIDAY MORNING IN WAKE OF A COLD FRONT FOLLOWING THE LOW. THE LOW
WILL WEAKEN AS IT DRIFTS EASTWARD INTO SOUTHERN ONTARIO THROUGH THE
DAY FRIDAY...WHILE KEEPING A WEAK TROUGH OVER LAKE SUPERIOR. HEAVY
FREEZING SPRAY WILL BE POSSIBLE THURSDAY NIGHT THROUGH FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 7 PM CST THIS EVENING FOR MIZ011.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR MIZ013.
WINTER STORM WARNING UNTIL 9 PM CST THIS EVENING FOR MIZ012.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST WEDNESDAY FOR MIZ006.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST WEDNESDAY FOR
LSZ248>251-265>267.
HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST WEDNESDAY FOR LSZ244-
245-263-264.
LAKE MICHIGAN...
GALE WARNING UNTIL 9 AM EST WEDNESDAY FOR LMZ250.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
359 PM EST TUE JAN 14 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 359 PM EST TUE JAN 14 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD MID/UPPER LEVEL TROUGH
FROM HUDSON BAY INTO THE CNTRL CONUS. A POTENT SHORTWAVE TROUGH
LOCATED OVER SRN WI WAS MOVING TOWARD SRN LOWER MI. AT THE SFC
CIRCULATION AROUND A 999 MB LOW PRES OVER E CNTRL WI RESULTED IN
STRONG NE WINDS INTO SRN UPPER MI. INCREASING NRLY WINDS ACROSS LAKE
SUPERIOR ALONG WITH 850 MB TEMPS IN THE -13C TO -16C RANGE SUPPORTED
LIGHT LES FOR LOCATIONS FAVORED BY NNE WINDS. STRONG 700-500 MB
QVECTOR CONV AND FGEN (FN/FS CONV) NEAR THE SHRTWV PIVOT POINT HAS
PRODUCED HEAVY SNOWFALL RATES OF AN INCH OR TWO PER HOUR OVER FAR
SRN UPPER (MNM) MI WHERE 7 INCHES HAD FALLEN BY 20Z. THIS ALSO
ALIGNED WELL WITH THE SRN EXTENT OF THE COLDER CLOUD TOPS...PER IR
LOOP.
LATE THIS AFTERNOON AND TONIGHT...SATELLITE/RADAR TRENDS AND SHORT
RANGE MODELS SUGGEST THAT THE COMMA HEAD PORTION OF THE SHRTWV WILL
MOVE INTO LAKE MI THIS EVENING BTWN 00Z-03Z AND DRAG THE BACK END OF
THE SNOW OUT OF THE SRN CWA. UNTIL THEN...MODERATE TO HEAVY SNOW
WILL CONTINUE OVER THE SOUTH ALONG WITH NE WINDS GUSTING TO AROUND
30 MPH. EXPECT THE LES IN CONVERGENT NRLY FLOW INTO WRN ALGER COUNTY
TO INCREASE AS THE DEEPER MOISTURE WITH THE SYNOPTIC SYSTEM EDGES
SLOWLY NORTHWARD. ALTHOUGH THE DEEPER MOISTURE WILL DEPART AFT
06Z...INSTABILITY WILL INCREASE AS CAA DROPS 850 MB TEMPS TO AROUND
-17C. MODERATE SNOWFALL AMOUNTS IN THE 3 TO 5 INCH RANGE ARE
EXPECTED MAINLY NEAR AU TRAIN/EBEN/CHATHAM...PER CONSENSUS OF HIGHER
RES MODELS. OVER THE WEST...INVERSION HEIGHTS AROUND 3K FT SHOULD
LIMIT SNOW AMOUNTS TO LESS THAN AN INCH.
WED....MID/UPPER LEVEL RIDGING WILL DEVELOP OVER THE NRN LAKES AHEAD
OF THE NEXT SHRTWV DIVING TOWARD SRN MANITOBA AND NRN MN. AT THE
SURFACE...A RIDGE FROM MN INTO NW ONTARIO WILL BUILD TOWARD THE SRN
GREAT LAKES AS A DEEP CLIPPER LOW MOVES TO NEAR LAKE WINNIPEG.
THIS WILL LEAD TO NORTH-NORTHWEST WINDS ACROSS LAKE SUPERIOR AND
WITH 850MB TEMPS AROUND -16C THERE WILL BE ENOUGH LAKE INSTABILITY
AND LOW LEVEL MOISTURE FOR LINGERING LAKE EFFECT. BUT WITH THE
SURFACE RIDGE QUICKLY SLIDING THROUGH THE UPPER GREAT LAKES...EXPECT
WINDS TO QUICKLY BACK THROUGH THE DAY. THE BACKING WINDS...ALONG
WITH DRIER LOW LEVEL AIR WILL BRING AN END TO THE LAKE EFFECT OVER
THE WEST AROUND EARLY AFTERNOON AND THEN OVER THE EAST BY LATE
AFTERNOON.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 446 AM EST TUE JAN 14 2014
A FAIRLY ACTIVE PATTERN IS IN STORE FOR THE LONG TERM PERIOD AND
LIKELY EVEN BEYOND THAT INTO THE MIDDLE OF NEXT WEEK. A RIDGE AXIS
ALONG THE WESTERN COAST OF THE CONUS AND CANADA WILL REMAIN IN PLACE
FOR MUCH OF THIS WEEK...WHILE A SERIES OF SHORTWAVES ROUND THE RIDGE
AND DIVE SOUTHEAST THROUGH THE GREAT LAKES REGION AND REINFORCE THE
UPPER TROUGH OVER THE EASTERN CONUS. WHILE THE MODELS
(GEM/GFS/ECMWF) ARE IN GREAT AGREEMENT IN THE LARGE SCALE
FEATURES...IT IS THE MESOSCALE FEATURES THAT DIFFER AND LEAD TO
UNCERTAINTY IN THE EXACT FORECAST.
WEDNESDAY...UPPER TROUGH ASSOCIATED WITH THE LOW AFFECTING PORTIONS
OF THE AREA TODAY WILL SHIFT TO THE EAST ON WEDNESDAY AND ALLOW AN
UPPER RIDGE TO QUICKLY MOVE EAST OVER THE CWA WEDNESDAY AFTERNOON
AND DEPART WEDNESDAY EVENING. AT THE SURFACE...THE DEPARTING LOW
WILL BE OVER CENTRAL LAKE HURON AT 12Z WHILE A HIGH PRESSURE RIDGE
WILL STRETCH FROM COLORADO THROUGH NORTHERN MINNESOTA. THIS WILL
LEAD TO NORTH-NORTHWEST WINDS ACROSS LAKE SUPERIOR AND WITH 850MB
TEMPS AROUND -16C THERE WILL BE ENOUGH LAKE INSTABILITY AND LOW
LEVEL MOISTURE FOR LINGERING LAKE EFFECT. BUT WITH THE SURFACE RIDGE
QUICKLY SLIDING THROUGH THE UPPER GREAT LAKES WEDNESDAY...EXPECT
WINDS TO QUICKLY BACK THROUGH THE DAY. THESE BACKING WINDS...ALONG
WITH DRIER LOW LEVEL AIR WILL BRING AN END TO THE LAKE EFFECT OVER
THE WEST AROUND EARLY AFTERNOON AND THEN OVER THE EAST BY LATE
AFTERNOON.
ATTENTION THEN SHIFTS TO THE SHORTWAVE IN THE GULF OF ALASKA THAT
IS ROUNDING THE RIDGE ALONG THE WEST COAST. THIS WAVE WILL QUICKLY
DIVE SOUTHEAST TONIGHT AND INITIAL PIECE OF UPPER LEVEL ENERGY
WILL REACH THE UPPER GREAT LAKES WEDNESDAY NIGHT. BROAD AREA OF
WARM AIR ADVECTION AHEAD OF THE SURFACE LOW WILL SPREAD LIGHT SNOW
ACROSS THE AREA WEDNESDAY NIGHT INTO THE FIRST PART OF THURSDAY
MORNING. MODEL HAVE BEEN TRENDING LOWER ON THE SNOWFALL WITH THIS
INITIAL SURGE AND HAVE FOLLOWED SUIT IN THE FORECAST (GENERAL 1-2
INCHES). IT APPEARS THAT THERE WILL BE A QUICK 3-6HR PERIOD OF LIGHT
SNOW THAT MOVES THROUGH OUT AHEAD OF THE SECONDARY WAVE AND LOW
ARRIVING MID TO LATE DAY THURSDAY. ALONG WITH THAT SNOW...EXPECT
GUSTY SOUTHWESTERLY WINDS (20-30KTS) TO PRODUCE SOME
BLOWING/DRIFTING SNOW. WITH THE LATEST TRENDS FOR SNOWFALL
AMOUNTS...DON/T THINK AN ADVISORY WILL BE NEEDED FOR THE
SYNOPTIC SNOWFALL AND BLOWING SNOW. THE BEST OPPORTUNITY FOR
ADVISORY CONDITIONS WILL BE FOR THE LAKE ENHANCEMENT OFF LAKE
MICHIGAN. DRY AIR FROM THE DEPARTING HIGH PRESSURE RIDGE WILL LIMIT
SNOW POTENTIAL WEDNESDAY EVENING...BUT IT SHOULD QUICKLY MOISTEN
AFTER 06-09Z WHEN THE SYNOPTIC PRECIPITATION ARRIVES. LOW LEVEL
WINDS LOOK TO BE MORE OUT OF THE SOUTHWEST AND THUS EXPECT THE
ENHANCEMENT TO BE FOCUSED A LITTLE FARTHER EAST THAN EXPECTED
YESTERDAY. DAY SHIFT SEEMED TO HAVE A DECENT HANDLE ON THAT IDEA
WITH IT STAYING EAST OF A LINE FROM MANISTIQUE TO TAHQUAMENON
FALLS. HAVE SNOWFALL AMOUNTS OF 3-4 INCHES IN THAT AREA AND
WITH THE GUSTY WINDS...WOULD THINK AN ADVISORY WOULD BE NEEDED
IN THE FUTURE. EXPECT THE ENHANCEMENT TO SHIFT EAST AND DIMINISH
THROUGH THE AFTERNOON AS THE WINDS BACK TOWARDS THE WEST AND LOW
LEVEL TEMPERATURES WARM.
THE MAIN QUESTION FOR THE SHORTWAVE WILL BE HOW THE LOW DIVING
SOUTHEAST FROM CANADA EVOLVES. 00Z MODELS HAVE CONTINUED THE TREND
STARTED YESTERDAY WITH A WEAKER AND MORE SOUTHWEST TRACK THROUGH
UPPER MICHIGAN. THAT SEEMS REASONABLE BASED OFF MID LEVEL
(850/700MB) POTENTIAL VORTICITY FIELDS SHOWING THE BEST ENERGY
DIVING SOUTHEAST THROUGH THE NORTHERN PLAINS AND INTO THE MID
MISSISSIPPI VALLEY THURSDAY AND THURSDAY NIGHT AS THE SECONDARY
WAVE DIVES INTO THE BACK SIDE OF THE TROUGH. IN ADDITION...THIS IS
LIKELY LEADING TO THE WEAKENING TREND TO THE SURFACE LOW AS IT
TRACKS THROUGH THE UPPER GREAT LAKES. VERY LEERY ON GETTING TOO
SPECIFIC ON THE LOW TRACK/INTENSITY AND ASSOCIATED WEATHER FEATURES
FOR THE WEDNESDAY NIGHT INTO FRIDAY PERIOD...LARGELY DUE TO THE
STRUGGLE SEEN WITH THE LOW TRACK AND ASSOCIATED PRECIP FOR THE LOW
TODAY. WAS HOPING ENSEMBLE MEMBERS WOULD HELP...BUT THEY ALL SEEM TO
SIDE WITH THEIR DETERMINISTIC RUNS AROUND 00Z FRIDAY. ALSO...SEEING
SIGNIFICANT JUMPS WITH TODAY/S SYSTEM LEADS TO MUCH LOWER CONFIDENCE
FOR THE EXACT DETAILS. UNFORTUNATELY...THE FORECAST DEPENDS ON THESE
LOW LEVEL FEATURES SINCE THE COLD AIR SURGING IN WILL LEAD TO LAKE
ENHANCEMENT AND THEN LAKE EFFECT THURSDAY AFTERNOON/EVENING INTO
FRIDAY MORNING. AT THIS POINT...WILL OPT TO TREND THE FORECAST
TOWARDS A GENERAL CONSENSUS OF THE ECMWF/GEM/UKMET AND AWAY FROM THE
STRONGER GFS AND FARTHER NORTH NAM. THIS SOLUTION WILL LIKELY LEAD
TO A LITTLE BIT OF A LULL IN THE PRECIPITATION DURING THE FIRST PART
OF THE DAY ON THURSDAY (AND POTENTIALLY THE ENTIRE DAY)...BEFORE THE
LOW MOVES THROUGH THE UPPER GREAT LAKES AREA AND SHIFTS WINDS TO THE
NORTH-NORTHWEST AND REALLY DEVELOPS THE LAKE ENHANCED AND THEN
EFFECT SNOW. THE LAKE EFFECT THURSDAY NIGHT INTO FRIDAY IS PROBABLY
THE MOST CERTAIN PART OF THE FORECAST AND WILL CONTINUE THE DEFINITE
POPS IN THE FAVORED SNOW BELTS. AMOUNTS WILL LARGELY DEPEND ON THE
INTENSITY/POSITION OF THE LOW (WHICH LOOKS TO SLOW OVER NORTHERN
LOWER MICHIGAN FRIDAY MORNING) AND THE ENHANCED CONVERGENCE
ASSOCIATED WITH IT. THUS...WITH THE FAVORABLE LAKE ENHANCED/EFFECT
CONDITIONS...HAVE TRENDED THE SNOWFALL AMOUNTS UP TO BE IN THE 3-6IN
RANGE FOR LOCATIONS NEAR LAKE SUPERIOR. WHEN FACTORING IN SOME
BLOWING AND DRIFTING WITH THE WINDS (20-35MPH NEAR LAKE
SUPERIOR)...THINK AT LEAST ADVISORIES WILL ALSO BE NEEDED AT SOME
POINT AND WILL CONTINUE TO MENTION IN THE HWO. WITH THE WEAKER
LOW PRODUCING A LITTLE LIGHTER WINDS...WILL TREND TOWARDS
LESS HARSH WORDING.
PAST THIS SYSTEM...APPEARS THAT THERE WILL BE ANOTHER COUPLE
SHORTWAVES/CLIPPERS MOVING THROUGH THE AREA FOR THE WEEKEND INTO
NEXT WEEK. ONE LOOKS TO MOVE THROUGH THE NORTHERN PLAINS AND MID
MISSISSIPPI VALLEY ON FRIDAY NIGHT AND SATURDAY AND ANOTHER
BRUSHING THE NORTHEAST PART OF THE UPPER GREAT LAKES REGION ON
SATURDAY NIGHT AND SUNDAY. MODELS VARY ON 850MB TEMPS DURING THIS
PERIOD...WITH A TREND TOWARDS WARMER VALUES OVER THE LAST 2-4
RUNS. WITH THE UNCERTAINTY...FOLLOWED A GENERAL CONSENSUS OF THE
MODELS WITH SOME INCREASE IN POPS WHEN LAKE EFFECT IS EXPECTED. THE
SECOND CLIPPER WILL SWEEP A COLD FRONT ACROSS UPPER MICHIGAN ON
SUNDAY AND LEAD TO ANOTHER PERIOD OF LAKE EFFECT SNOW. SHOULD SEE
A WEAK RIDGE BUILD OVER THE AREA FOR MONDAY BUT THEN ANOTHER
CLIPPER SYSTEM NEARS THE AREA ON MONDAY NIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 109 PM EST TUE JAN 14 2014
LAKE EFFECT SNOW SHOWERS WILL CONTINUE INTO TONIGHT AND WED MORNING.
EXPECT MVFR CONDITIONS AT KCMX AND KIWD BUT CONDITIONS WILL LOWER
TO IFR AT KSAW BY MID AFTERNOON AND CONTINUE THROUGH MUCH OF TONIGHT
AS THERE IS MORE OF A POTENTIAL FOR MODERATE LAKE EFFECT SNOW AND
BLOWING SNOW AS NORTH WINDS INCREASE TO 15 TO 25 MPH BY THIS
EVENING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 359 PM EST TUE JAN 14 2014
NORTH WINDS OF 30 KNOTS OVER ERN LAKE SUPERIOR TONIGHT AS A SFC LOW
PASSES SOUTH AND EAST OF REGION WILL PRODUCE HEAVY FREEZING SPRAY.
EXPECT THE WINDS TO DIMINISH BRIEFLY ON WEDNESDAY AS A HIGH PRESSURE
RIDGE CROSSES THE REGION. LOW PRESSURE CROSSING LAKE WINNIPEG LATE
WEDNESDAY AFTERNOON WILL THEN SINK ACROSS LAKE SUPERIOR ON THURSDAY.
SW GALES OF 35 KTS ARE POSSIBLE WEDNESDAY NIGHT OVER EASTERN SECTIONS.
N-NW GALES OF 35 KTS ARE ALSO POSSIBLE LATE THURSDAY AFTERNOON THROUGH
FRIDAY MORNING IN WAKE OF A COLD FRONT FOLLOWING THE LOW. THE LOW
WILL WEAKEN AS IT DRIFTS EASTWARD INTO SOUTHERN ONTARIO THROUGH THE
DAY FRIDAY...WHILE KEEPING A WEAK TROUGH OVER LAKE SUPERIOR. HEAVY
FREEZING SPRAY WILL BE POSSIBLE THURSDAY NIGHT THROUGH FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 7 PM CST THIS EVENING FOR MIZ011.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR MIZ013.
WINTER STORM WARNING UNTIL 9 PM CST THIS EVENING FOR MIZ012.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST WEDNESDAY FOR MIZ006.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM 7 PM THIS EVENING TO 1 PM EST
WEDNESDAY FOR LSZ248>251-265>267.
HEAVY FREEZING SPRAY WARNING FROM 7 PM THIS EVENING TO 7 AM EST
WEDNESDAY FOR LSZ244-245-263-264.
LAKE MICHIGAN...
GALE WARNING FROM 7 PM THIS EVENING TO 9 AM EST WEDNESDAY FOR
LMZ250.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
118 PM EST TUE JAN 14 2014
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 329 AM EST TUE JAN 14 2014
A BURST OF SNOW WILL MOVE INTO SOUTHWEST MICHIGAN TOWARD MID DAY.
THE STEADIEST SNOW WILL OCCUR NORTH OF I-96. THIS SNOW SHOULD
DIMINISH ACROSS AREAS SOUTH OF I-96 BY LATE AFTERNOON...WHILE IT
SHOULD CONTINUE ACROSS CENTRAL LOWER MICHIGAN. THEN BY TONIGHT MORE
SNOW WILL ROTATE ACROSS ALL OF SOUTHWEST MICHIGAN. THIS SNOW WILL
FINALLY DIMINISH TOWARD MID DAY WEDNESDAY. WINDS WILL BECOME BRISK
BY TONIGHT CAUSING BLOWING AND DRIFTING SNOW.
WHERE THE SNOW IS THE MOST PERSISTENT...MAINLY NORTH OF A MUSKEGON
TO MOUNT PLEASANT LINE...3 TO 6 INCHES OF SNOW CAN BE EXPECTED BY
NOON WEDNESDAY. ANOTHER CLIPPER ARRIVES LATE WEDNESDAY NIGHT INTO
THURSDAY....WITH ANOTHER 1 TO 3 INCHES OF SNOW EXPECTED.
&&
.UPDATE...
ISSUED AT 117 PM EST TUE JAN 14 2014
WILL ADD OTTAWA...ALLEGAN AND VAN BUREN TO THE ADVISORY FOR THE
WRAPAROUND SYNOPTIC AND LAKE EFFECT SNOWS TONIGHT. WILL RUN IT FOR
THOSE COUNTIES FROM MIDNIGHT TO 1 PM WEDNESDAY. OTHERWISE...WILL
BE TWEAKING SNOW AMOUNTS DOWN FOR TODAY AS SFC LOW IS TRACKING TOO
FAR NORTH TO GIVE FORECAST AREA AS MUCH SNOW AS PREVIOUSLY
FORECAST. THERE WILL BE A LULL LATER THIS AFTERNOON AND EVENING AS
THE DRY SLOT MOVES THROUGH.
UPDATE ISSUED AT 745 AM EST TUE JAN 14 2014
I DID SOME MINOR CHANGES TO OUR SHORT TERM GRIDS TO SLOW DOWN THE
START OF THE SNOW ACROSS THE AREA. THE LATEST RUNS OF THE HRRR AND
RAP MODELS...PLUS THE 06Z NAM12 SUGGEST THE SNOW WILL NOT GET
STARTED IN OUR WESTERN COUNTIES UNTIL BETWEEN NOON AND 1 PM. GIVEN
THE DRY AIR AHEAD OF THIS SYSTEM THAT WOULD MAKE SENSE TOO. ALSO
USING THE TIMING TOOL IT ALSO SUGGESTS EARLY AFTERNOON FOR THE
LAKE SHORE COUNTIES.
THE PRIMARY BAND OF SNOW WILL LIKELY NOT AMOUNT TO MUCH OVER MOST
OF THE CWA. THE NORTHERN COUNTIES... IN THE ADVISORY AREA... COULD
SEE 1 TO 3 INCHES WITH THE 3 INCH AMOUNTS BEING NORTH OF ROUTE 10.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 329 AM EST TUE JAN 14 2014
WILL ONLY MAKE MINOR TWEAKS TO THE CURRENT HEADLINES. FIRST WILL
DELAY THE START TIME UNTIL 16Z. THEN WILL ALSO ADD MUSKEGON COUNTY
TO THE ADVISORY.
VERY WRAPPED UP CLIPPER SYSTEM TO IMPACT THE REGION LATER TODAY AND
LINGER INTO THE FIRST HALF OF WED. MODEL TRENDS CONTINUE TO SHOW A
SLIGHTLY FURTHER NORTH TRACK TO THE SURFACE LOW...GENERALLY JUST
SOUTH OF HIGHWAY 10. THIS WILL KEEP THE STEADIEST SNOW ACROSS
CENTRAL LOWER WHERE THE ADVISORY IS PRESENTLY. EXPECT A BURST OF
WARM ADVECTION SNOW ARRIVING AROUND 16Z...WHEN THE ADVISORY WILL GO
INTO AFFECT. THIS SHOULD IMPACT AREAS NW OF A HOLLAND TO CLARE LINE
WITH THE STEADIEST SNOW...WITH AREAS SE SEEING A MORE SHORT LIVED
BURST.
THEN TOWARD LATE AFTERNOON WE WILL SEE A DRY SLOT PUNCH INTO THE
CWA. EXPECT MOST AREAS OUTSIDE OF THE ADVISORY AREA WILL SEE A LULL
IN THE SNOWFALL. IT SHOULD CONTINUE OVER THE ADVISORY REGION...BUT
SHOULD LIGHTEN UP SOMEWHAT.
THEN INTO MID/LATE EVENING...AND CONTINUING INTO WED MORNING...THE
DEFORMATION ZONE WILL DRAG ACROSS ALL THE CWA WITH A RETURN TO
STEADIER SNOWS. HAVE ADDED MUSKEGON COUNTY TO THE ADVISORY FOR
MAINLY A STEADIER SNOW DURING THIS PERIOD ALONG WITH SOME LAKE
ENHANCEMENT WITH A WSW FLOW. THE FLOW PIVOTS TO THE NW LATE TONIGHT
WHICH WILL SPRAY ALL THE LAKESHORE COUNTIES WITH SOME LAKE
ENHANCEMENT.
ACCUMS BY NOON WED SHOULD BE IN THE 5 TO 9 INCH RANGE FOR AREAS IN
THE ADVISORY...AND 2 TO 5 INCHES ELSEWHERE.
WE WILL NEED TO MONITOR THE WIND ASPECT OF THE SYSTEM TONIGHT. AS
WE GET INTO THE COLD ADVECTION ON THE BACKSIDE OF THE SYSTEM WSW
WINDS WILL INCREASE AND COULD LEAD TO SIGNIFICANT BLOWING AND
DRIFTING. WE MAY NEED TO EXPAND THE ADVISORY IN AREA IF THIS
BECOMES MORE OF A CONCERN.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 329 AM EST TUE JAN 14 2014
SNOW SHOWERS ARE EXPECTED INTO FRIDAY THEN IT MAY BE QUIET INTO
EARLY NEXT WEEK. TEMPERATURES WILL BE COLDER THEN OVER THE PAST
WEEKEND BUT NOT REALLY SIGNIFICANTLY COLDER THAN NORMAL. SOME
WARMING IS EXPECTED LATE IN THE WEEKEND INTO EARLY NEXT WEEK BUT IT
WILL NOT LAST LONG.
WE CURRENTLY HAVE A SIGNIFICANT STRATOSPHERIC WARMING EVENT OVER
NORTHERN RUSSIA (SIBERIA)... NEAR 10MB. THIS MATTERS BECAUSE THE
RESULT OF THIS IS TYPICALLY A SPLIT IN THE POLAR VORTEX. YOU MAY
REMEMBER WE SAW THIS HAPPEN DURING THE FIRST WEEK OF JANUARY TOO.
SIMILARLY THE POLAR VORTEX SPLIT THEN TOO. SINCE THE MODELS DO IN
FACT SHOW THIS HAPPENING ONCE AGAIN AND ONCE AGAIN WE HAVE
STRATOSPHERIC WARMING EVENT IT WOULD SEEM THIS EVENT WILL IMPACT OUR
WEATHER OVER THE NEXT WEEK OR SO.
THE RESULT OF THE SPLITTING OF THE POLAR VORTEX WILL BE A SOUTHWARD
DISPLACEMENT PART OF THE POLAR VORTEX OVER NORTH AMERICA. ALL THE
MODELS SHOW THIS. THE ONLY QUESTION IS TO WHAT EXTENT THIS HAPPENS.
THE PART OF THE POLAR VORTEX OVER NORTH AMERICA DROPS SOUTH FROM
ARCTIC OCEAN SHORES OF CANADA TO SOUTHERN HUDSON BAY BY SUNDAY.
CLEARLY THIS WILL BRING THE VERY COLD AIR MUCH CLOSER TO MICHIGAN
THAN IT HAS BEEN OVER THE PAST FOUR DAYS.
WHILE THE POLAR VORTEX DIGS SOUTH OVER THE NEXT FEW DAYS...THE ECMWF
DRIVES A SHORTWAVE CURRENTLY RIDING OVER THE TOP OF THE UPPER RIDGE
IN SOUTHERN ALASKA SOUTH OF CHICAGO BY FRIDAY MORNING. IT DIGS IT SO
STRONGLY IT CLOSES OFF AN UPPER LOW WELL SOUTHWEST OF CHICAGO BY
FRIDAY MORNING. THIS HAS CONTINUITY IN THE ECMWF FOR AT LEAST THE
PAST 3 RUNS BUT THE 14TH/00Z VERSION OF THIS IS FARTHER SOUTH THAN
THE OTHERS. THE CANADIAN GEM IS SIMILAR WITH THIS SYSTEM TOO. IN ANY
EVENT THE AMOUNT OF DIGGING OF THESE SYSTEMS WILL MAKE A DIFFERENCE
IN HOW COLD WE GET AND HOW MUCH SNOW WE GET. MODEL AGREEMENT IS GOOD
TILL THURSDAY MORNING...THEN THAT ECMWF MORE STRONGLY DIGGING UPPER
WAVE BRINGS COLDER AIR SIGNIFICANTLY FARTHER SOUTH FRIDAY THAN IS
SHOWN BUT THE GFS. THIS ALSO RESULTS IN THE ECMWF BEING SLOWER THAN
THE GFS IN TERMS OF MOVING SYSTEMS THROUGH THE AREA. BY THE WAY THE
CANADIAN GEM IS MORE SIMILAR TO THE ECMWF THAN THE GFS ON THIS
FEATURE.
THE RESULT OF ALL THIS IS RIDGING WEDNESDAY NIGHT HEAD OF THE NEXT
SYSTEM. THAT SHOULD QUIET DOWN ANY LAKE EFFECT THAT WOULD LINGER
INTO WEDNESDAY AFTERNOON BY EARLY WEDNESDAY EVENING. AFTER MIDNIGHT
A SOUTHWEST FLOW EVENT SETS UP AND THIS SHOULD BRING SNOW TO THE
LAKE SHORE COUNTIES NORTH OF MKG BEFORE SUNRISE THURSDAY MORNING.
WHAT HAPPENS AFTER THAT IS HARD TO TOTALLY SAY. IF THE ECMWF IS
CORRECT THERE WOULD BE A LONGER PERIOD OF SNOW ON THURSDAY AND IT
WOULD AMOUNT TO MORE SNOW COVERING A LARGELY AREA OF OUR CWA. IF THE
GFS IS CORRECT WE DO NOT GET MUCH SNOW ANYWHERE IN OR CWA AS MOST OF
THE DYNAMICS WOULD BE OVER UPPER MICHIGAN.
SINCE THE GFS DOES NOT DIG THE LEAD SYSTEM AS MUCH...TRAILING WAVE
ENERGY DEVELOPS A SYSTEM ON SATURDAY THAT THE ECMWF AND CANADIAN DO
NOT HAVE. SHORTWAVE RIDGING BETWEEN THE DEPARTING TROUGH AND THE
NEXT WAVE ROTATING AROUND THE POLAR VORTEX WILL FAVOR A DRY PERIOD
FROM SAT INTO MONDAY WITH MILDER TEMPERATURES. THE NEXT SYSTEM WOULD
BE THE MIDDLE OF NEXT WEEK AND THAT WOULD BRING DOWN VERY COLD AIR
BEHIND IT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1247 PM EST TUE JAN 14 2014
BAND OF SNOW STRETCHING FROM JUST WEST OF KMKG TO NEAR CHICAGO IS
POISED TO MOVE IN ACROSS THE TERMINALS OVER THE NEXT FEW HOURS.
KMKG SHOULD SEE IT START AROUND 18Z...WITH IT SPREADING EAST FROM
THERE. THIS LOOKS TO BE A BURST OF ABOUT 2 HRS WORTH OF IFR AND
LOWER CONDITIONS IN THE SNOW AT EACH SITE BEFORE IT DIMINISHES
GREATLY AS THE DRY SLOT MOVES IN. EACH SITE WILL BE LEFT WITH SOME
FLURRIES...DZ...OR FZDZ DEPENDING ON THE SFC TEMP IN SOME REDUCED
VSBYS. WINDS WILL BECOME GUSTY FROM THE SW TO AROUND 25 KNOTS OR
SO.
SNOW WILL MOVE BACK IN ON THE BACKSIDE OF THE SYSTEM LATER THIS
EVENING AND INTO THE OVERNIGHT HOURS. IFR WILL BE LIKELY AT MOST
WRN LOCATIONS AS THE SNOW MOVES BACK INTO THE AREA DUE TO SOME
LAKE ENHANCEMENT. INLAND LOCATIONS SEEM TO HAVE A BETTER CHC AT
REMAINING MVFR BUT HAVE A CHANCE AT IFR. SNOW SHOULD THEN DIMINISH
ON WED MORNING.
&&
.MARINE...
ISSUED AT 329 AM EST TUE JAN 14 2014
ISSUED SMALL CRAFT ADVISORY FOR LATER TODAY. THEN RAMPED UP TO A
GALE WARNING LATE TONIGHT INTO WED MORNING.
&&
.HYDROLOGY...
ISSUED AT 325 PM EST MON JAN 13 2014
FLOOD ADVISORIES ARE IN EFFECT FOR THE KALAMAZOO RIVER AT NEW
RICHMOND...THE SYCAMORE CREEK AT HOLT...AND THE PERE MARQUETTE RIVER
AT SCOTTVILLE. ALL THESE RIVERS ARE ABOVE BANKFULL BUT BELOW FLOOD
STAGE. MINOR FLOODING ALONG LOW LYING AREAS ADJACENT TO THE RIVERS
IS THE MAIN IMPACT.
ELSEWHERE...RISES CONTINUE ON MANY LARGE AND SMALL RIVERS AND
STREAMS...BUT NO IMMEDIATE FLOODING RISKS ARE NOTED. ICE COVERAGE ON
THE GRAND AT ROBINSON TWP IS THINNING AND CURRENTLY STABLE (NOT
MOVING IN CHUNKS). THIS IS GOOD NEWS AND REDUCES THE THREAT FOR ICE
JAMS. NO ABRUPT RISES ARE SHOWN ON AREA HYDROGRAPHS...ANOTHER
INDICATOR THAT ICE IS BEHAVING.
THE OUTLOOK FOR RIVERS THIS WEEK IS FOR THEM TO BE CRESTING (IF THEY
HAVEN`T ALREADY) AND THEN FALLING BACK DOWN. A REFORMATION OF ICE IS
LIKELY ON RIVERS THAT ONLY HAD SMALL RISES FROM THE RECENT RAINS AND
SNOW MELT. MAXIMUM ICE DEVELOPMENT WOULD LIKELY OCCUR OVER THE
WEEKEND BUT TEMPERATURES ESPECIALLY AT NIGHT WILL BE CONDUCIVE TO
ICE DEVELOPMENT.
SNOW WATER EQUIVALENT VALUES (VIA NOHRSC ANALYSIS AND IN-SITU
MEASUREMENTS) ARE QUITE HIGH ACROSS SW LOWER MI...GENERALLY BETWEEN
1 AND 4 INCHES. THESE VALUES WILL ONLY BE GOING UP THIS WEEK AS WE
ADD FRESH SNOW TO A VERY DENSE AND CRUSTY SNOW PACK. SOMETHING TO BE
THINKING ABOUT WHENEVER THE NEXT THAW COMES.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 1 PM EST
WEDNESDAY FOR MIZ056-064-071-072.
WINTER WEATHER ADVISORY UNTIL 1 PM EST WEDNESDAY FOR MIZ037>040-
043>046-050.
LM...SMALL CRAFT ADVISORY UNTIL 1 AM EST WEDNESDAY FOR LMZ844>849.
GALE WARNING FROM 1 AM TO 11 AM EST WEDNESDAY FOR LMZ844>849.
&&
$$
UPDATE...OSTUNO
SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...WDM
AVIATION...NJJ
HYDROLOGY...HOVING
MARINE...OSTUNO
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1247 PM EST TUE JAN 14 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 329 AM EST TUE JAN 14 2014
A BURST OF SNOW WILL MOVE INTO SOUTHWEST MICHIGAN TOWARD MID DAY.
THE STEADIEST SNOW WILL OCCUR NORTH OF I-96. THIS SNOW SHOULD
DIMINISH ACROSS AREAS SOUTH OF I-96 BY LATE AFTERNOON...WHILE IT
SHOULD CONTINUE ACROSS CENTRAL LOWER MICHIGAN. THEN BY TONIGHT MORE
SNOW WILL ROTATE ACROSS ALL OF SOUTHWEST MICHIGAN. THIS SNOW WILL
FINALLY DIMINISH TOWARD MID DAY WEDNESDAY. WINDS WILL BECOME BRISK
BY TONIGHT CAUSING BLOWING AND DRIFTING SNOW.
WHERE THE SNOW IS THE MOST PERSISTENT...MAINLY NORTH OF A MUSKEGON
TO MOUNT PLEASANT LINE...5 TO 9 INCHES OF SNOW CAN BE EXPECTED BY
NOON WEDNESDAY. AREAS SOUTH OF A MUSKEGON TO MOUNT PLEASANT LINE
SHOULD SEE BETWEEN 2 AND 5 INCHES OF SNOW BY NOON WEDNESDAY.
ANOTHER CLIPPER ARRIVES LATE WEDNESDAY NIGHT INTO THURSDAY. THIS
SYSTEM SHOULD PRODUCE ANOTHER 1 TO 3 INCHES OF SNOW.
&&
.UPDATE...
ISSUED AT 745 AM EST TUE JAN 14 2014
I DID SOME MINOR CHANGES TO OUR SHORT TERM GRIDS TO SLOW DOWN THE
START OF THE SNOW ACROSS THE AREA. THE LATEST RUNS OF THE HRRR AND
RAP MODELS...PLUS THE 06Z NAM12 SUGGEST THE SNOW WILL NOT GET
STARTED IN OUR WESTERN COUNTIES UNTIL BETWEEN NOON AND 1 PM. GIVEN
THE DRY AIR AHEAD OF THIS SYSTEM THAT WOULD MAKE SENSE TOO. ALSO
USING THE TIMING TOOL IT ALSO SUGGESTS EARLY AFTERNOON FOR THE
LAKE SHORE COUNTIES.
THE PRIMARY BAND OF SNOW WILL LIKELY NOT AMOUNT TO MUCH OVER MOST
OF THE CWA. THE NORTHERN COUNTIES... IN THE ADVISORY AREA... COULD
SEE 1 TO 3 INCHES WITH THE 3 INCH AMOUNTS BEING NORTH OF ROUTE 10.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 329 AM EST TUE JAN 14 2014
WILL ONLY MAKE MINOR TWEAKS TO THE CURRENT HEADLINES. FIRST WILL
DELAY THE START TIME UNTIL 16Z. THEN WILL ALSO ADD MUSKEGON COUNTY
TO THE ADVISORY.
VERY WRAPPED UP CLIPPER SYSTEM TO IMPACT THE REGION LATER TODAY AND
LINGER INTO THE FIRST HALF OF WED. MODEL TRENDS CONTINUE TO SHOW A
SLIGHTLY FURTHER NORTH TRACK TO THE SURFACE LOW...GENERALLY JUST
SOUTH OF HIGHWAY 10. THIS WILL KEEP THE STEADIEST SNOW ACROSS
CENTRAL LOWER WHERE THE ADVISORY IS PRESENTLY. EXPECT A BURST OF
WARM ADVECTION SNOW ARRIVING AROUND 16Z...WHEN THE ADVISORY WILL GO
INTO AFFECT. THIS SHOULD IMPACT AREAS NW OF A HOLLAND TO CLARE LINE
WITH THE STEADIEST SNOW...WITH AREAS SE SEEING A MORE SHORT LIVED
BURST.
THEN TOWARD LATE AFTERNOON WE WILL SEE A DRY SLOT PUNCH INTO THE
CWA. EXPECT MOST AREAS OUTSIDE OF THE ADVISORY AREA WILL SEE A LULL
IN THE SNOWFALL. IT SHOULD CONTINUE OVER THE ADVISORY REGION...BUT
SHOULD LIGHTEN UP SOMEWHAT.
THEN INTO MID/LATE EVENING...AND CONTINUING INTO WED MORNING...THE
DEFORMATION ZONE WILL DRAG ACROSS ALL THE CWA WITH A RETURN TO
STEADIER SNOWS. HAVE ADDED MUSKEGON COUNTY TO THE ADVISORY FOR
MAINLY A STEADIER SNOW DURING THIS PERIOD ALONG WITH SOME LAKE
ENHANCEMENT WITH A WSW FLOW. THE FLOW PIVOTS TO THE NW LATE TONIGHT
WHICH WILL SPRAY ALL THE LAKESHORE COUNTIES WITH SOME LAKE
ENHANCEMENT.
ACCUMS BY NOON WED SHOULD BE IN THE 5 TO 9 INCH RANGE FOR AREAS IN
THE ADVISORY...AND 2 TO 5 INCHES ELSEWHERE.
WE WILL NEED TO MONITOR THE WIND ASPECT OF THE SYSTEM TONIGHT. AS
WE GET INTO THE COLD ADVECTION ON THE BACKSIDE OF THE SYSTEM WSW
WINDS WILL INCREASE AND COULD LEAD TO SIGNIFICANT BLOWING AND
DRIFTING. WE MAY NEED TO EXPAND THE ADVISORY IN AREA IF THIS
BECOMES MORE OF A CONCERN.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 329 AM EST TUE JAN 14 2014
SNOW SHOWERS ARE EXPECTED INTO FRIDAY THEN IT MAY BE QUIET INTO
EARLY NEXT WEEK. TEMPERATURES WILL BE COLDER THEN OVER THE PAST
WEEKEND BUT NOT REALLY SIGNIFICANTLY COLDER THAN NORMAL. SOME
WARMING IS EXPECTED LATE IN THE WEEKEND INTO EARLY NEXT WEEK BUT IT
WILL NOT LAST LONG.
WE CURRENTLY HAVE A SIGNIFICANT STRATOSPHERIC WARMING EVENT OVER
NORTHERN RUSSIA (SIBERIA)... NEAR 10MB. THIS MATTERS BECAUSE THE
RESULT OF THIS IS TYPICALLY A SPLIT IN THE POLAR VORTEX. YOU MAY
REMEMBER WE SAW THIS HAPPEN DURING THE FIRST WEEK OF JANUARY TOO.
SIMILARLY THE POLAR VORTEX SPLIT THEN TOO. SINCE THE MODELS DO IN
FACT SHOW THIS HAPPENING ONCE AGAIN AND ONCE AGAIN WE HAVE
STRATOSPHERIC WARMING EVENT IT WOULD SEEM THIS EVENT WILL IMPACT OUR
WEATHER OVER THE NEXT WEEK OR SO.
THE RESULT OF THE SPLITTING OF THE POLAR VORTEX WILL BE A SOUTHWARD
DISPLACEMENT PART OF THE POLAR VORTEX OVER NORTH AMERICA. ALL THE
MODELS SHOW THIS. THE ONLY QUESTION IS TO WHAT EXTENT THIS HAPPENS.
THE PART OF THE POLAR VORTEX OVER NORTH AMERICA DROPS SOUTH FROM
ARCTIC OCEAN SHORES OF CANADA TO SOUTHERN HUDSON BAY BY SUNDAY.
CLEARLY THIS WILL BRING THE VERY COLD AIR MUCH CLOSER TO MICHIGAN
THAN IT HAS BEEN OVER THE PAST FOUR DAYS.
WHILE THE POLAR VORTEX DIGS SOUTH OVER THE NEXT FEW DAYS...THE ECMWF
DRIVES A SHORTWAVE CURRENTLY RIDING OVER THE TOP OF THE UPPER RIDGE
IN SOUTHERN ALASKA SOUTH OF CHICAGO BY FRIDAY MORNING. IT DIGS IT SO
STRONGLY IT CLOSES OFF AN UPPER LOW WELL SOUTHWEST OF CHICAGO BY
FRIDAY MORNING. THIS HAS CONTINUITY IN THE ECMWF FOR AT LEAST THE
PAST 3 RUNS BUT THE 14TH/00Z VERSION OF THIS IS FARTHER SOUTH THAN
THE OTHERS. THE CANADIAN GEM IS SIMILAR WITH THIS SYSTEM TOO. IN ANY
EVENT THE AMOUNT OF DIGGING OF THESE SYSTEMS WILL MAKE A DIFFERENCE
IN HOW COLD WE GET AND HOW MUCH SNOW WE GET. MODEL AGREEMENT IS GOOD
TILL THURSDAY MORNING...THEN THAT ECMWF MORE STRONGLY DIGGING UPPER
WAVE BRINGS COLDER AIR SIGNIFICANTLY FARTHER SOUTH FRIDAY THAN IS
SHOWN BUT THE GFS. THIS ALSO RESULTS IN THE ECMWF BEING SLOWER THAN
THE GFS IN TERMS OF MOVING SYSTEMS THROUGH THE AREA. BY THE WAY THE
CANADIAN GEM IS MORE SIMILAR TO THE ECMWF THAN THE GFS ON THIS
FEATURE.
THE RESULT OF ALL THIS IS RIDGING WEDNESDAY NIGHT HEAD OF THE NEXT
SYSTEM. THAT SHOULD QUIET DOWN ANY LAKE EFFECT THAT WOULD LINGER
INTO WEDNESDAY AFTERNOON BY EARLY WEDNESDAY EVENING. AFTER MIDNIGHT
A SOUTHWEST FLOW EVENT SETS UP AND THIS SHOULD BRING SNOW TO THE
LAKE SHORE COUNTIES NORTH OF MKG BEFORE SUNRISE THURSDAY MORNING.
WHAT HAPPENS AFTER THAT IS HARD TO TOTALLY SAY. IF THE ECMWF IS
CORRECT THERE WOULD BE A LONGER PERIOD OF SNOW ON THURSDAY AND IT
WOULD AMOUNT TO MORE SNOW COVERING A LARGELY AREA OF OUR CWA. IF THE
GFS IS CORRECT WE DO NOT GET MUCH SNOW ANYWHERE IN OR CWA AS MOST OF
THE DYNAMICS WOULD BE OVER UPPER MICHIGAN.
SINCE THE GFS DOES NOT DIG THE LEAD SYSTEM AS MUCH...TRAILING WAVE
ENERGY DEVELOPS A SYSTEM ON SATURDAY THAT THE ECMWF AND CANADIAN DO
NOT HAVE. SHORTWAVE RIDGING BETWEEN THE DEPARTING TROUGH AND THE
NEXT WAVE ROTATING AROUND THE POLAR VORTEX WILL FAVOR A DRY PERIOD
FROM SAT INTO MONDAY WITH MILDER TEMPERATURES. THE NEXT SYSTEM WOULD
BE THE MIDDLE OF NEXT WEEK AND THAT WOULD BRING DOWN VERY COLD AIR
BEHIND IT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1247 PM EST TUE JAN 14 2014
BAND OF SNOW STRETCHING FROM JUST WEST OF KMKG TO NEAR CHICAGO IS
POISED TO MOVE IN ACROSS THE TERMINALS OVER THE NEXT FEW HOURS.
KMKG SHOULD SEE IT START AROUND 18Z...WITH IT SPREADING EAST FROM
THERE. THIS LOOKS TO BE A BURST OF ABOUT 2 HRS WORTH OF IFR AND
LOWER CONDITIONS IN THE SNOW AT EACH SITE BEFORE IT DIMINISHES
GREATLY AS THE DRY SLOT MOVES IN. EACH SITE WILL BE LEFT WITH SOME
FLURRIES...DZ...OR FZDZ DEPENDING ON THE SFC TEMP IN SOME REDUCED
VSBYS. WINDS WILL BECOME GUSTY FROM THE SW TO AROUND 25 KNOTS OR
SO.
SNOW WILL MOVE BACK IN ON THE BACKSIDE OF THE SYSTEM LATER THIS
EVENING AND INTO THE OVERNIGHT HOURS. IFR WILL BE LIKELY AT MOST
WRN LOCATIONS AS THE SNOW MOVES BACK INTO THE AREA DUE TO SOME
LAKE ENHANCEMENT. INLAND LOCATIONS SEEM TO HAVE A BETTER CHC AT
REMAINING MVFR BUT HAVE A CHANCE AT IFR. SNOW SHOULD THEN DIMINISH
ON WED MORNING.
&&
.MARINE...
ISSUED AT 329 AM EST TUE JAN 14 2014
ISSUED SMALL CRAFT ADVISORY FOR LATER TODAY. THEN RAMPED UP TO A
GALE WARNING LATE TONIGHT INTO WED MORNING.
&&
.HYDROLOGY...
ISSUED AT 325 PM EST MON JAN 13 2014
FLOOD ADVISORIES ARE IN EFFECT FOR THE KALAMAZOO RIVER AT NEW
RICHMOND...THE SYCAMORE CREEK AT HOLT...AND THE PERE MARQUETTE RIVER
AT SCOTTVILLE. ALL THESE RIVERS ARE ABOVE BANKFULL BUT BELOW FLOOD
STAGE. MINOR FLOODING ALONG LOW LYING AREAS ADJACENT TO THE RIVERS
IS THE MAIN IMPACT.
ELSEWHERE...RISES CONTINUE ON MANY LARGE AND SMALL RIVERS AND
STREAMS...BUT NO IMMEDIATE FLOODING RISKS ARE NOTED. ICE COVERAGE ON
THE GRAND AT ROBINSON TWP IS THINNING AND CURRENTLY STABLE (NOT
MOVING IN CHUNKS). THIS IS GOOD NEWS AND REDUCES THE THREAT FOR ICE
JAMS. NO ABRUPT RISES ARE SHOWN ON AREA HYDROGRAPHS...ANOTHER
INDICATOR THAT ICE IS BEHAVING.
THE OUTLOOK FOR RIVERS THIS WEEK IS FOR THEM TO BE CRESTING (IF THEY
HAVEN`T ALREADY) AND THEN FALLING BACK DOWN. A REFORMATION OF ICE IS
LIKELY ON RIVERS THAT ONLY HAD SMALL RISES FROM THE RECENT RAINS AND
SNOW MELT. MAXIMUM ICE DEVELOPMENT WOULD LIKELY OCCUR OVER THE
WEEKEND BUT TEMPERATURES ESPECIALLY AT NIGHT WILL BE CONDUCIVE TO
ICE DEVELOPMENT.
SNOW WATER EQUIVALENT VALUES (VIA NOHRSC ANALYSIS AND IN-SITU
MEASUREMENTS) ARE QUITE HIGH ACROSS SW LOWER MI...GENERALLY BETWEEN
1 AND 4 INCHES. THESE VALUES WILL ONLY BE GOING UP THIS WEEK AS WE
ADD FRESH SNOW TO A VERY DENSE AND CRUSTY SNOW PACK. SOMETHING TO BE
THINKING ABOUT WHENEVER THE NEXT THAW COMES.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 1 PM EST WEDNESDAY FOR MIZ037>040-
043>046-050.
LM...SMALL CRAFT ADVISORY UNTIL 1 AM EST WEDNESDAY FOR LMZ844>849.
GALE WARNING FROM 1 AM TO 11 AM EST WEDNESDAY FOR LMZ844>849.
&&
$$
UPDATE...WDM
SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...WDM
AVIATION...NJJ
HYDROLOGY...HOVING
MARINE...OSTUNO
AREA FORECAST DISCUSSION
NWS DULUTH MN
113 PM CST TUE JAN 14 2014
.UPDATE...
ISSUED AT 1202 PM CST TUE JAN 14 2014
ADDED WASHBURN AND SAWYER COUNTY TO WSY BASED ON REPORT OF 5
INCHES 3 MILES SOUTH OF SPOONER AND SAT IMAGERY STILL SHOWING
CONVECTIVE CLOUS MOVING NORTH.
UPDATE ISSUED AT 1126 AM CST TUE JAN 14 2014
CHANGED SOUTH SHORE FORECAST AS 925/85H WIND ALIGNS AMIDST A
RELATIVELY MOIST SYNOPTIC SCALE WITH COLD ADVECTION IN BNDRY LYR.
CONTINUED THE TREND TOWARDS MORE SUNSHINE OVER MOST OF NE MN ZONES
AS PER LATEST SAT ANIMATION.
UPDATE ISSUED AT 1038 AM CST TUE JAN 14 2014
LATEST SPC MESO ANALYSIS SHOWS AREA OF 85H FRONTOGENESIS IS MOVING
ACROSS SERN CORNER OF CWA. SAT IMAGERY SHOWS CONVECTIVE APPEARANCE
TO CLOUD MASS OVER SERN CWA WITH REPORTED SFC OBS UNDERNEATH OF
1/2SM TO 1 1/2SM VISIBILITY. LATEST HOPWRF AND HRRR 3KM INDICATE 3
TO 5 INCHES SHOULD FALL OVER SRN PRICE COUNTY. A FEW INCHES ARE
EXPECTED OVER EXTREME SRN SAWYER/WASHBURN COUNTY AS WELL.
ELSEWHERE FAIRLY BENIGN PATTERN AS DEEP LAYER COLD ADVECTION
CONTINUES. ONE CHALLENGE TODAY IS CLOUD COVER. SKIES HAVE
PARTIALLY CLEARED IN WRN/NRN CWA SO HAVE LOWERED COVERAGE IN
GRIDS. A SECONDARY SHORTWAVE INDICATED ON RAP40 OVER SRN MANITOBA
...ASSOCIATED WITH CYCLONIC SHEAR FROM UPPER JET...IS MOVING SOUTH
AND HAS SPREAD ANOTHER AREA OF LIGHT SNOW INTO THE NWRN CORNER OF
MN. HAVE INCREASED CLOUDS THIS AFTN OVER WRN CWA AND ADDED
FLURRIES TO ACCOUNT FOR THIS FEATURE. LOWERED MAX TEMPS JUST A
DEGREE OR TWO BASED ON LATEST OBS AND LAV GUIDANCE.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 325 AM CST TUE JAN 14 2014
AT 315AM/0915Z...THERE WAS A CLIPPER SYSTEM MOVING EAST THROUGH
SOUTHERN MINNESOTA. WEAK HIGH PRESSURE WAS CENTERED OVER EASTERN
MANITOBA AND WESTERN ONTARIO. THE CLIPPER SYSTEM HAD A SUBTLE
INVERTED TROUGH EXTENDING TO THE NNW THROUGH THE EASTERN DAKOTAS
AND WESTERN MANITOBA. MUCH OF THE SOUTHERN FORECAST AND SOUTH HAD
CLOUDY SKIES WITH LIGHT TO MODERATE SNOW MOVING THROUGH THE AREA.
THE HEAVIES SNOW WAS GENERALLY SOUTH OF THE FORECAST AREA. THE
NORTHERN FORECAST AREA HAD PARTLY TO MOSTLY CLEAR SKIES. THERE WAS
A BAND OF LOW OVERCAST CLOUDS ALONG AND NEAR THE INVERTED
TROUGH...AND THE BAND WAS PRODUCING LIGHT SNOW IN EASTERN NORTH
DAKOTA AND NW MINNESOTA. THE WINDS WERE CALM ACROSS THE NORTHERN
FORECAST AREA...WHILE THE SOUTHERN FORECAST AREA HAD VERY LIGHT N
TO NNE WINDS. TEMPERATURES RANGED FROM THE LOW 20S IN NW WISCONSIN
UNDER THE CLOUDY SKIES TO THE SINGLE DIGITS AND TEENS BELOW ZERO
ACROSS THE NORTHERN FORECAST AREA UNDER THE CLEAR SKIES.
TODAY...THE CLIPPER SYSTEM WILL BRING LIGHT TO MODERATE SNOW TO
THE SOUTHERN FORECAST AREA. THE LATEST MODELS INDICATED A BIT MORE
SNOW ACROSS THE SOUTH...ENOUGH TO WARRANT A WINTER WEATHER
ADVISORY FOR PRICE COUNTY. THE SOUTHERN HALF OF PRICE COUNTY COULD
SEE ABOUT 2 TO 4 INCHES. AREAS SOUTH OF
HINCKLEY...GRANTSBURG...SPOONER...AND HAYWARD COULD SEE ABOUT 2 TO
3 INCHES IN THEIR RESPECTIVE COUNTIES. THE SNOW WILL BEGIN TO
DIMINISH AND EXIT THE REGION LATE THIS MORNING AND THIS AFTERNOON.
LIGHT SNOW OR FLURRIES COULD CONTINUE ACROSS THE WESTERN FORECAST
AREA DUE TO THE LINGERING INVERTED TROUGH FROM THE CLIPPER OVER
THE NORTHERN PLAINS. HIGH TEMPERATURES SHOULD RANGE FROM THE UPPER
TEENS AND LOW 20S IN NW WISCONSIN TO THE SINGLE DIGITS AND LOW
TEENS ACROSS MOST OF NE MINNESOTA.
TONIGHT...THERE WILL LIKELY BE SOME CLEARING TONIGHT AS A RIDGE OF
HIGH PRESSURE MOVES INTO THE REGION. THE CLEARING AND DECREASING
WINDS WILL HELP TEMPERATURES DROP TO THE SINGLE DIGITS AND LOW
TEENS BELOW ZERO ACROSS MOST OF THE NORTHLAND. THERE MIGHT BE SOME
LIGHT LAKE EFFECT SNOW ALONG AND NEAR THE GOGEBIC RANGE IN IRON
AND ASHLAND COUNTIES DUE TO THE COLD NORTHERLY FLOW OVER WESTERN
LAKE SUPERIOR...BUT LITTLE IF ANY ACCUMULATION IS EXPECTED.
WEDNESDAY...ANOTHER CANADIAN CLIPPER WILL BEGIN TO AFFECT THE
NORTHLAND DURING THE AFTERNOON. IT WILL MOVE NW SASKATCHEWAN
TO CENTRAL MANITOBA BY THE LATE AFTERNOON. IT WILL QUICKLY BRING
LIGHT SNOW TO WESTERN AND MUCH OF THE CENTRAL FORECAST AREA DURING
THE AFTERNOON AHEAD OF ITS APPROACHING WARM FRONT FROM THE WEST. I
INCREASED THE PCPN CHANCES QUITE A BIT BASED ON THE LATEST MODELS
BEING IN PRETTY GOOD AGREEMENT. I LEANED ON THE SREF FOR THOSE
PCPN CHANCES. MUCH OF NE MINNESOTA WILL GET ABOUT A HALF TO 1.5
INCHES BY THE EVENING. SNOW WILL CONTINUE WEDNESDAY NIGHT. I
INCLUDED A SLIGHT CHANCE OF FREEZING DRIZZLE FOR THE BRAINERD
LAKES AREA DURING THE LATE AFTERNOON. IT LOOKS LIKE THE ONSET OF
THE PCPN WILL BE SNOW DUE TO SATURATION TO THE UPPER LEVELS...BUT
ONCE THE INITIAL MAIN BAND OF SNOW MOVES THROUGH...THE MID AND
UPPER LEVEL SATURATION COULD BE LOST...LEAVING A RELATIVELY WARM
LOW LEVEL SATURATED LAYER WITH LITTLE POTENTIAL FOR ICE CRYSTAL
NUCLEATION FOR SNOW.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 325 AM CST TUE JAN 14 2014
EMPHASIS IN THE EXTENDED PERIOD WILL BE EARLY AND REVOLVE AROUND
SNOW AND WIND WITH A STRONG AREA OF LOW PRESSURE THAT WILL MOVE
FROM MANITOBA WEDNESDAY EVENING TO THE EASTERN LAKE
SUPERIOR/NORTHERN MICHIGAN AREA BY THURSDAY EVENING.
STRONG WAA WILL MOVE WEST TO EAST THROUGH THE NORTHLAND WEDNESDAY
NIGHT ALONG WITH A POTENT SHORTWAVE. STRONG CAA WILL MOVE
QUICKLY INTO NORTHERN MINNESOTA LATE WEDNESDAY NIGHT. AN AREA OF
SNOW WILL OCCUR IN RESPONSE TO THE WAA/SHORTWAVE AND WE HAVE
SNOWFALL JUST WEDNESDAY NIGHT FROM A HALF TO AROUND 3
INCHES...WITH THE HIGHEST AMOUNTS MOST LIKELY ACROSS THE
ARROWHEAD...AND THE BRAINERD LAKES REGION SEEING THE LOWER
AMOUNTS. SOUNDINGS SUGGEST SOME FREEZING DRIZZLE WILL ALSO BE
POSSIBLE THROUGH AT LEAST MIDNIGHT OVER THE SOUTHERN HALF TO TWO
THIRDS OF THE NORTHLAND AS DEEPER MOISTURE MOVES EAST. ALTHOUGH
THE MODELS ARE IN DECENT AGREEMENT...THERE DOES REMAIN SOME ISSUES
ON TIMING...STRENGTH...AND EXACT TRACK OF THE LOW. THIS WILL PLAY
A CRITICAL ROLE IN HOW STRONG THE WINDS GET AND WHEN THE PEAK WIND
PERIOD WILL OCCUR. WE EXPECT WINDS TO INCREASE OUT OF THE WEST-
NORTHWEST LATE WEDNESDAY NIGHT...MAINLY OVER THE WESTERN
HALF...THEN INCREASE FURTHER THROUGH THE DAY THURSDAY.
TEMPERATURES WILL LIKELY RISE WEDNESDAY NIGHT...WITH THEM DROPPING
THROUGH THE DAY OVER MOST OF MINNESOTA DUE TO THE STRONG CAA.
PERIODS OF SNOW WILL CONTINUE TO BE POSSIBLE THURSDAY AS ANOTHER
POTENT SHORTWAVE MOVES THROUGH THE NORTHLAND. MOST AREAS THURSDAY
SHOULD ONLY SEE LIGHT SNOW ACCUMULATIONS. THE SNOWBELT OF THE
SOUTH SHORE OF LAKE SUPERIOR...MAINLY ASHLAND/IRON COUNTIES...WILL
SEE LAKE EFFECT SNOW SHOWERS INCREASE THROUGH THE DAY
THURSDAY...WITH SEVERAL INCHES POSSIBLE.
A RIDGE OF HIGH PRESSURE WILL MOVE INTO WESTERN MINNESOTA THURSDAY
NIGHT CAUSING MOST OF THE SNOW TO END. NORTHERLY WINDS AND COLD
TEMPERATURES ALOFT WILL KEEP STRONGER SNOW SHOWERS GOING ALONG THE
SOUTH SHORE. SEVERAL MORE INCHES OF SNOW LOOK LIKELY ACROSS
NORTHERN ASHLAND/IRON COUNTIES...WITH SOME LOCALIZED HEAVY AMOUNTS
POSSIBLE.
A WEAK LOW WILL BRING SOME LIGHT SNOW TO PORTIONS OF THE AREA
FRIDAY NIGHT...THEN THE REST OF THE EXTENDED LOOKS RELATIVELY
DRY.
HIGHS THURSDAY WILL BE IN THE TEENS OVER NORTHERN MINNESOTA AND
LOWER TO MID TWENTIES OVER OUR SOUTHERN ZONES...BUT WILL DROP
THROUGH THE DAY OVER MOST OF MINNESOTA. HIGHS FRIDAY WILL ONLY
RANGE FROM 5 TO 15...THEN THEY WILL MODERATE THROUGH THE WEEKEND
REACHING THE TWENTIES FOR MOST AREAS SUNDAY/MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 110 PM CST TUE JAN 14 2014
VFR SKIES COVER MOST OF TAF SITES EXCEPT FOR HYR WHERE IFR CIGS
ARE OCCURING BECAUSE OF SNOW. THERE IS A AREA OF MVFR-IFR CIGS
MOVING EAST THROUGH WESTERN MN AND WILL OVERSPREAD TAF SITES AFTER
21Z. THERE WILL BE A IMPROVEMENT TO MVFR-VFR TONIGHT BEFORE MVFR
CIGS MOVE BACK IN WEDNESDAY MORNING AHEAD OF NEXT SYSTEM.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH -2 12 9 23 / 0 70 60 50
INL -12 16 15 16 / 10 70 70 50
BRD -5 17 15 21 / 10 80 50 50
HYR -1 13 11 25 / 20 30 70 50
ASX 1 14 12 27 / 40 20 70 50
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR
WIZ007>009.
LS...NONE.
&&
$$
UPDATE...CANNON
SHORT TERM...GROCHOCINSKI
LONG TERM...MELDE
AVIATION...STEWART
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1207 PM CST TUE JAN 14 2014
.UPDATE...
ISSUED AT 1202 PM CST TUE JAN 14 2014
ADDED WASHBURN AND SAWYER COUNTY TO WSY BASED ON REPORT OF 5
INCHES 3 MILES SOUTH OF SPOONER AND SAT IMAGERY STILL SHOWING
CONVECTIVE CLOUS MOVING NORTH.
UPDATE ISSUED AT 1126 AM CST TUE JAN 14 2014
CHANGED SOUTH SHORE FORECAST AS 925/85H WIND ALIGNS AMIDST A
RELATIVELY MOIST SYNOPTIC SCALE WITH COLD ADVECTION IN BNDRY LYR.
CONTINUED THE TREND TOWARDS MORE SUNSHINE OVER MOST OF NE MN ZONES
AS PER LATEST SAT ANIMATION.
UPDATE ISSUED AT 1038 AM CST TUE JAN 14 2014
LATEST SPC MESO ANALYSIS SHOWS AREA OF 85H FRONTOGENESIS IS MOVING
ACROSS SERN CORNER OF CWA. SAT IMAGERY SHOWS CONVECTIVE APPEARANCE
TO CLOUD MASS OVER SERN CWA WITH REPORTED SFC OBS UNDERNEATH OF
1/2SM TO 1 1/2SM VISIBILITY. LATEST HOPWRF AND HRRR 3KM INDICATE 3
TO 5 INCHES SHOULD FALL OVER SRN PRICE COUNTY. A FEW INCHES ARE
EXPECTED OVER EXTREME SRN SAWYER/WASHBURN COUNTY AS WELL.
ELSEWHERE FAIRLY BENIGN PATTERN AS DEEP LAYER COLD ADVECTION
CONTINUES. ONE CHALLENGE TODAY IS CLOUD COVER. SKIES HAVE
PARTIALLY CLEARED IN WRN/NRN CWA SO HAVE LOWERED COVERAGE IN
GRIDS. A SECONDARY SHORTWAVE INDICATED ON RAP40 OVER SRN MANITOBA
...ASSOCIATED WITH CYCLONIC SHEAR FROM UPPER JET...IS MOVING SOUTH
AND HAS SPREAD ANOTHER AREA OF LIGHT SNOW INTO THE NWRN CORNER OF
MN. HAVE INCREASED CLOUDS THIS AFTN OVER WRN CWA AND ADDED
FLURRIES TO ACCOUNT FOR THIS FEATURE. LOWERED MAX TEMPS JUST A
DEGREE OR TWO BASED ON LATEST OBS AND LAV GUIDANCE.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 325 AM CST TUE JAN 14 2014
AT 315AM/0915Z...THERE WAS A CLIPPER SYSTEM MOVING EAST THROUGH
SOUTHERN MINNESOTA. WEAK HIGH PRESSURE WAS CENTERED OVER EASTERN
MANITOBA AND WESTERN ONTARIO. THE CLIPPER SYSTEM HAD A SUBTLE
INVERTED TROUGH EXTENDING TO THE NNW THROUGH THE EASTERN DAKOTAS
AND WESTERN MANITOBA. MUCH OF THE SOUTHERN FORECAST AND SOUTH HAD
CLOUDY SKIES WITH LIGHT TO MODERATE SNOW MOVING THROUGH THE AREA.
THE HEAVIES SNOW WAS GENERALLY SOUTH OF THE FORECAST AREA. THE
NORTHERN FORECAST AREA HAD PARTLY TO MOSTLY CLEAR SKIES. THERE WAS
A BAND OF LOW OVERCAST CLOUDS ALONG AND NEAR THE INVERTED
TROUGH...AND THE BAND WAS PRODUCING LIGHT SNOW IN EASTERN NORTH
DAKOTA AND NW MINNESOTA. THE WINDS WERE CALM ACROSS THE NORTHERN
FORECAST AREA...WHILE THE SOUTHERN FORECAST AREA HAD VERY LIGHT N
TO NNE WINDS. TEMPERATURES RANGED FROM THE LOW 20S IN NW WISCONSIN
UNDER THE CLOUDY SKIES TO THE SINGLE DIGITS AND TEENS BELOW ZERO
ACROSS THE NORTHERN FORECAST AREA UNDER THE CLEAR SKIES.
TODAY...THE CLIPPER SYSTEM WILL BRING LIGHT TO MODERATE SNOW TO
THE SOUTHERN FORECAST AREA. THE LATEST MODELS INDICATED A BIT MORE
SNOW ACROSS THE SOUTH...ENOUGH TO WARRANT A WINTER WEATHER
ADVISORY FOR PRICE COUNTY. THE SOUTHERN HALF OF PRICE COUNTY COULD
SEE ABOUT 2 TO 4 INCHES. AREAS SOUTH OF
HINCKLEY...GRANTSBURG...SPOONER...AND HAYWARD COULD SEE ABOUT 2 TO
3 INCHES IN THEIR RESPECTIVE COUNTIES. THE SNOW WILL BEGIN TO
DIMINISH AND EXIT THE REGION LATE THIS MORNING AND THIS AFTERNOON.
LIGHT SNOW OR FLURRIES COULD CONTINUE ACROSS THE WESTERN FORECAST
AREA DUE TO THE LINGERING INVERTED TROUGH FROM THE CLIPPER OVER
THE NORTHERN PLAINS. HIGH TEMPERATURES SHOULD RANGE FROM THE UPPER
TEENS AND LOW 20S IN NW WISCONSIN TO THE SINGLE DIGITS AND LOW
TEENS ACROSS MOST OF NE MINNESOTA.
TONIGHT...THERE WILL LIKELY BE SOME CLEARING TONIGHT AS A RIDGE OF
HIGH PRESSURE MOVES INTO THE REGION. THE CLEARING AND DECREASING
WINDS WILL HELP TEMPERATURES DROP TO THE SINGLE DIGITS AND LOW
TEENS BELOW ZERO ACROSS MOST OF THE NORTHLAND. THERE MIGHT BE SOME
LIGHT LAKE EFFECT SNOW ALONG AND NEAR THE GOGEBIC RANGE IN IRON
AND ASHLAND COUNTIES DUE TO THE COLD NORTHERLY FLOW OVER WESTERN
LAKE SUPERIOR...BUT LITTLE IF ANY ACCUMULATION IS EXPECTED.
WEDNESDAY...ANOTHER CANADIAN CLIPPER WILL BEGIN TO AFFECT THE
NORTHLAND DURING THE AFTERNOON. IT WILL MOVE NW SASKATCHEWAN
TO CENTRAL MANITOBA BY THE LATE AFTERNOON. IT WILL QUICKLY BRING
LIGHT SNOW TO WESTERN AND MUCH OF THE CENTRAL FORECAST AREA DURING
THE AFTERNOON AHEAD OF ITS APPROACHING WARM FRONT FROM THE WEST. I
INCREASED THE PCPN CHANCES QUITE A BIT BASED ON THE LATEST MODELS
BEING IN PRETTY GOOD AGREEMENT. I LEANED ON THE SREF FOR THOSE
PCPN CHANCES. MUCH OF NE MINNESOTA WILL GET ABOUT A HALF TO 1.5
INCHES BY THE EVENING. SNOW WILL CONTINUE WEDNESDAY NIGHT. I
INCLUDED A SLIGHT CHANCE OF FREEZING DRIZZLE FOR THE BRAINERD
LAKES AREA DURING THE LATE AFTERNOON. IT LOOKS LIKE THE ONSET OF
THE PCPN WILL BE SNOW DUE TO SATURATION TO THE UPPER LEVELS...BUT
ONCE THE INITIAL MAIN BAND OF SNOW MOVES THROUGH...THE MID AND
UPPER LEVEL SATURATION COULD BE LOST...LEAVING A RELATIVELY WARM
LOW LEVEL SATURATED LAYER WITH LITTLE POTENTIAL FOR ICE CRYSTAL
NUCLEATION FOR SNOW.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 325 AM CST TUE JAN 14 2014
EMPHASIS IN THE EXTENDED PERIOD WILL BE EARLY AND REVOLVE AROUND
SNOW AND WIND WITH A STRONG AREA OF LOW PRESSURE THAT WILL MOVE
FROM MANITOBA WEDNESDAY EVENING TO THE EASTERN LAKE
SUPERIOR/NORTHERN MICHIGAN AREA BY THURSDAY EVENING.
STRONG WAA WILL MOVE WEST TO EAST THROUGH THE NORTHLAND WEDNESDAY
NIGHT ALONG WITH A POTENT SHORTWAVE. STRONG CAA WILL MOVE
QUICKLY INTO NORTHERN MINNESOTA LATE WEDNESDAY NIGHT. AN AREA OF
SNOW WILL OCCUR IN RESPONSE TO THE WAA/SHORTWAVE AND WE HAVE
SNOWFALL JUST WEDNESDAY NIGHT FROM A HALF TO AROUND 3
INCHES...WITH THE HIGHEST AMOUNTS MOST LIKELY ACROSS THE
ARROWHEAD...AND THE BRAINERD LAKES REGION SEEING THE LOWER
AMOUNTS. SOUNDINGS SUGGEST SOME FREEZING DRIZZLE WILL ALSO BE
POSSIBLE THROUGH AT LEAST MIDNIGHT OVER THE SOUTHERN HALF TO TWO
THIRDS OF THE NORTHLAND AS DEEPER MOISTURE MOVES EAST. ALTHOUGH
THE MODELS ARE IN DECENT AGREEMENT...THERE DOES REMAIN SOME ISSUES
ON TIMING...STRENGTH...AND EXACT TRACK OF THE LOW. THIS WILL PLAY
A CRITICAL ROLE IN HOW STRONG THE WINDS GET AND WHEN THE PEAK WIND
PERIOD WILL OCCUR. WE EXPECT WINDS TO INCREASE OUT OF THE WEST-
NORTHWEST LATE WEDNESDAY NIGHT...MAINLY OVER THE WESTERN
HALF...THEN INCREASE FURTHER THROUGH THE DAY THURSDAY.
TEMPERATURES WILL LIKELY RISE WEDNESDAY NIGHT...WITH THEM DROPPING
THROUGH THE DAY OVER MOST OF MINNESOTA DUE TO THE STRONG CAA.
PERIODS OF SNOW WILL CONTINUE TO BE POSSIBLE THURSDAY AS ANOTHER
POTENT SHORTWAVE MOVES THROUGH THE NORTHLAND. MOST AREAS THURSDAY
SHOULD ONLY SEE LIGHT SNOW ACCUMULATIONS. THE SNOWBELT OF THE
SOUTH SHORE OF LAKE SUPERIOR...MAINLY ASHLAND/IRON COUNTIES...WILL
SEE LAKE EFFECT SNOW SHOWERS INCREASE THROUGH THE DAY
THURSDAY...WITH SEVERAL INCHES POSSIBLE.
A RIDGE OF HIGH PRESSURE WILL MOVE INTO WESTERN MINNESOTA THURSDAY
NIGHT CAUSING MOST OF THE SNOW TO END. NORTHERLY WINDS AND COLD
TEMPERATURES ALOFT WILL KEEP STRONGER SNOW SHOWERS GOING ALONG THE
SOUTH SHORE. SEVERAL MORE INCHES OF SNOW LOOK LIKELY ACROSS
NORTHERN ASHLAND/IRON COUNTIES...WITH SOME LOCALIZED HEAVY AMOUNTS
POSSIBLE.
A WEAK LOW WILL BRING SOME LIGHT SNOW TO PORTIONS OF THE AREA
FRIDAY NIGHT...THEN THE REST OF THE EXTENDED LOOKS RELATIVELY
DRY.
HIGHS THURSDAY WILL BE IN THE TEENS OVER NORTHERN MINNESOTA AND
LOWER TO MID TWENTIES OVER OUR SOUTHERN ZONES...BUT WILL DROP
THROUGH THE DAY OVER MOST OF MINNESOTA. HIGHS FRIDAY WILL ONLY
RANGE FROM 5 TO 15...THEN THEY WILL MODERATE THROUGH THE WEEKEND
REACHING THE TWENTIES FOR MOST AREAS SUNDAY/MONDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 542 AM CST TUE JAN 14 2014
A CLIPPER MOVING INTO SOUTHERN WISCONSIN THIS MORNING WILL
CONTINUE EAST TODAY. SNOW WAS FALLING FROM THE BRAINERD LAKES
REGION EAST INTO NORTHERN WISCONSIN. MVFR/IFR CONDITIONS WERE
OCCURRING DUE TO THE CLIPPER OVER THE SOUTHERN HALF OF THE
NORTHLAND. MORE IFR/MVFR CEILINGS WERE MOVING SOUTH FROM FAR
NORTHERN MINNESOTA AND SOME LIGHT SNOW WILL OCCUR UNDER THESE
CLOUDS. THE MVFR/IFR CEILINGS MOVING SOUTH SHOULD ARRIVE IN KHIB
OVER THE NEXT 2 HOURS...AND IN KDLH IN 3 TO 4 HOURS. OVERALL...WE
EXPECT MVFR/PATCHY IFR CONDITIONS TODAY INTO THIS EVENING.
CONFIDENCE IS LOWER TONIGHT IN HOW QUICKLY THE MVFR CEILINGS WILL
DISSIPATE. AT THIS TIME...WE THINK SKIES WILL SLOWLY CLEAR FROM
WEST TO EAST LATER TONIGHT...WITH MVFR CEILINGS REMAINING OVER
NORTHERN WISCONSIN DUE TO LAKE PROCESSES WITH NORTHERLY WINDS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH -2 12 9 23 / 0 70 60 50
INL -12 16 15 16 / 10 70 70 50
BRD -5 17 15 21 / 10 80 50 50
HYR -1 13 11 25 / 20 30 70 50
ASX 1 14 12 27 / 40 20 70 50
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR
WIZ007>009.
LS...NONE.
&&
$$
UPDATE...CANNON
SHORT TERM...GROCHOCINSKI
LONG TERM...MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1128 AM CST TUE JAN 14 2014
.UPDATE...
ISSUED AT 1126 AM CST TUE JAN 14 2014
CHANGED SOUTH SHORE FORECAST AS 925/85H WIND ALIGNS AMIDST A
RELATIVELY MOIST SYNOPTIC SCALE WITH COLD ADVECTION IN BNDRY LYR.
CONTINUED THE TREND TOWARDS MORE SUNSHINE OVER MOST OF NE MN ZONES
AS PER LATEST SAT ANIMATION.
UPDATE ISSUED AT 1038 AM CST TUE JAN 14 2014
LATEST SPC MESO ANALYSIS SHOWS AREA OF 85H FRONTOGENESIS IS MOVING
ACROSS SERN CORNER OF CWA. SAT IMAGERY SHOWS CONVECTIVE APPEARANCE
TO CLOUD MASS OVER SERN CWA WITH REPORTED SFC OBS UNDERNEATH OF
1/2SM TO 1 1/2SM VISIBILITY. LATEST HOPWRF AND HRRR 3KM INDICATE 3
TO 5 INCHES SHOULD FALL OVER SRN PRICE COUNTY. A FEW INCHES ARE
EXPECTED OVER EXTREME SRN SAWYER/WASHBURN COUNTY AS WELL.
ELSEWHERE FAIRLY BENIGN PATTERN AS DEEP LAYER COLD ADVECTION
CONTINUES. ONE CHALLENGE TODAY IS CLOUD COVER. SKIES HAVE
PARTIALLY CLEARED IN WRN/NRN CWA SO HAVE LOWERED COVERAGE IN
GRIDS. A SECONDARY SHORTWAVE INDICATED ON RAP40 OVER SRN MANITOBA
...ASSOCIATED WITH CYCLONIC SHEAR FROM UPPER JET...IS MOVING SOUTH
AND HAS SPREAD ANOTHER AREA OF LIGHT SNOW INTO THE NWRN CORNER OF
MN. HAVE INCREASED CLOUDS THIS AFTN OVER WRN CWA AND ADDED
FLURRIES TO ACCOUNT FOR THIS FEATURE. LOWERED MAX TEMPS JUST A
DEGREE OR TWO BASED ON LATEST OBS AND LAV GUIDANCE.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 325 AM CST TUE JAN 14 2014
AT 315AM/0915Z...THERE WAS A CLIPPER SYSTEM MOVING EAST THROUGH
SOUTHERN MINNESOTA. WEAK HIGH PRESSURE WAS CENTERED OVER EASTERN
MANITOBA AND WESTERN ONTARIO. THE CLIPPER SYSTEM HAD A SUBTLE
INVERTED TROUGH EXTENDING TO THE NNW THROUGH THE EASTERN DAKOTAS
AND WESTERN MANITOBA. MUCH OF THE SOUTHERN FORECAST AND SOUTH HAD
CLOUDY SKIES WITH LIGHT TO MODERATE SNOW MOVING THROUGH THE AREA.
THE HEAVIES SNOW WAS GENERALLY SOUTH OF THE FORECAST AREA. THE
NORTHERN FORECAST AREA HAD PARTLY TO MOSTLY CLEAR SKIES. THERE WAS
A BAND OF LOW OVERCAST CLOUDS ALONG AND NEAR THE INVERTED
TROUGH...AND THE BAND WAS PRODUCING LIGHT SNOW IN EASTERN NORTH
DAKOTA AND NW MINNESOTA. THE WINDS WERE CALM ACROSS THE NORTHERN
FORECAST AREA...WHILE THE SOUTHERN FORECAST AREA HAD VERY LIGHT N
TO NNE WINDS. TEMPERATURES RANGED FROM THE LOW 20S IN NW WISCONSIN
UNDER THE CLOUDY SKIES TO THE SINGLE DIGITS AND TEENS BELOW ZERO
ACROSS THE NORTHERN FORECAST AREA UNDER THE CLEAR SKIES.
TODAY...THE CLIPPER SYSTEM WILL BRING LIGHT TO MODERATE SNOW TO
THE SOUTHERN FORECAST AREA. THE LATEST MODELS INDICATED A BIT MORE
SNOW ACROSS THE SOUTH...ENOUGH TO WARRANT A WINTER WEATHER
ADVISORY FOR PRICE COUNTY. THE SOUTHERN HALF OF PRICE COUNTY COULD
SEE ABOUT 2 TO 4 INCHES. AREAS SOUTH OF
HINCKLEY...GRANTSBURG...SPOONER...AND HAYWARD COULD SEE ABOUT 2 TO
3 INCHES IN THEIR RESPECTIVE COUNTIES. THE SNOW WILL BEGIN TO
DIMINISH AND EXIT THE REGION LATE THIS MORNING AND THIS AFTERNOON.
LIGHT SNOW OR FLURRIES COULD CONTINUE ACROSS THE WESTERN FORECAST
AREA DUE TO THE LINGERING INVERTED TROUGH FROM THE CLIPPER OVER
THE NORTHERN PLAINS. HIGH TEMPERATURES SHOULD RANGE FROM THE UPPER
TEENS AND LOW 20S IN NW WISCONSIN TO THE SINGLE DIGITS AND LOW
TEENS ACROSS MOST OF NE MINNESOTA.
TONIGHT...THERE WILL LIKELY BE SOME CLEARING TONIGHT AS A RIDGE OF
HIGH PRESSURE MOVES INTO THE REGION. THE CLEARING AND DECREASING
WINDS WILL HELP TEMPERATURES DROP TO THE SINGLE DIGITS AND LOW
TEENS BELOW ZERO ACROSS MOST OF THE NORTHLAND. THERE MIGHT BE SOME
LIGHT LAKE EFFECT SNOW ALONG AND NEAR THE GOGEBIC RANGE IN IRON
AND ASHLAND COUNTIES DUE TO THE COLD NORTHERLY FLOW OVER WESTERN
LAKE SUPERIOR...BUT LITTLE IF ANY ACCUMULATION IS EXPECTED.
WEDNESDAY...ANOTHER CANADIAN CLIPPER WILL BEGIN TO AFFECT THE
NORTHLAND DURING THE AFTERNOON. IT WILL MOVE NW SASKATCHEWAN
TO CENTRAL MANITOBA BY THE LATE AFTERNOON. IT WILL QUICKLY BRING
LIGHT SNOW TO WESTERN AND MUCH OF THE CENTRAL FORECAST AREA DURING
THE AFTERNOON AHEAD OF ITS APPROACHING WARM FRONT FROM THE WEST. I
INCREASED THE PCPN CHANCES QUITE A BIT BASED ON THE LATEST MODELS
BEING IN PRETTY GOOD AGREEMENT. I LEANED ON THE SREF FOR THOSE
PCPN CHANCES. MUCH OF NE MINNESOTA WILL GET ABOUT A HALF TO 1.5
INCHES BY THE EVENING. SNOW WILL CONTINUE WEDNESDAY NIGHT. I
INCLUDED A SLIGHT CHANCE OF FREEZING DRIZZLE FOR THE BRAINERD
LAKES AREA DURING THE LATE AFTERNOON. IT LOOKS LIKE THE ONSET OF
THE PCPN WILL BE SNOW DUE TO SATURATION TO THE UPPER LEVELS...BUT
ONCE THE INITIAL MAIN BAND OF SNOW MOVES THROUGH...THE MID AND
UPPER LEVEL SATURATION COULD BE LOST...LEAVING A RELATIVELY WARM
LOW LEVEL SATURATED LAYER WITH LITTLE POTENTIAL FOR ICE CRYSTAL
NUCLEATION FOR SNOW.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 325 AM CST TUE JAN 14 2014
EMPHASIS IN THE EXTENDED PERIOD WILL BE EARLY AND REVOLVE AROUND
SNOW AND WIND WITH A STRONG AREA OF LOW PRESSURE THAT WILL MOVE
FROM MANITOBA WEDNESDAY EVENING TO THE EASTERN LAKE
SUPERIOR/NORTHERN MICHIGAN AREA BY THURSDAY EVENING.
STRONG WAA WILL MOVE WEST TO EAST THROUGH THE NORTHLAND WEDNESDAY
NIGHT ALONG WITH A POTENT SHORTWAVE. STRONG CAA WILL MOVE
QUICKLY INTO NORTHERN MINNESOTA LATE WEDNESDAY NIGHT. AN AREA OF
SNOW WILL OCCUR IN RESPONSE TO THE WAA/SHORTWAVE AND WE HAVE
SNOWFALL JUST WEDNESDAY NIGHT FROM A HALF TO AROUND 3
INCHES...WITH THE HIGHEST AMOUNTS MOST LIKELY ACROSS THE
ARROWHEAD...AND THE BRAINERD LAKES REGION SEEING THE LOWER
AMOUNTS. SOUNDINGS SUGGEST SOME FREEZING DRIZZLE WILL ALSO BE
POSSIBLE THROUGH AT LEAST MIDNIGHT OVER THE SOUTHERN HALF TO TWO
THIRDS OF THE NORTHLAND AS DEEPER MOISTURE MOVES EAST. ALTHOUGH
THE MODELS ARE IN DECENT AGREEMENT...THERE DOES REMAIN SOME ISSUES
ON TIMING...STRENGTH...AND EXACT TRACK OF THE LOW. THIS WILL PLAY
A CRITICAL ROLE IN HOW STRONG THE WINDS GET AND WHEN THE PEAK WIND
PERIOD WILL OCCUR. WE EXPECT WINDS TO INCREASE OUT OF THE WEST-
NORTHWEST LATE WEDNESDAY NIGHT...MAINLY OVER THE WESTERN
HALF...THEN INCREASE FURTHER THROUGH THE DAY THURSDAY.
TEMPERATURES WILL LIKELY RISE WEDNESDAY NIGHT...WITH THEM DROPPING
THROUGH THE DAY OVER MOST OF MINNESOTA DUE TO THE STRONG CAA.
PERIODS OF SNOW WILL CONTINUE TO BE POSSIBLE THURSDAY AS ANOTHER
POTENT SHORTWAVE MOVES THROUGH THE NORTHLAND. MOST AREAS THURSDAY
SHOULD ONLY SEE LIGHT SNOW ACCUMULATIONS. THE SNOWBELT OF THE
SOUTH SHORE OF LAKE SUPERIOR...MAINLY ASHLAND/IRON COUNTIES...WILL
SEE LAKE EFFECT SNOW SHOWERS INCREASE THROUGH THE DAY
THURSDAY...WITH SEVERAL INCHES POSSIBLE.
A RIDGE OF HIGH PRESSURE WILL MOVE INTO WESTERN MINNESOTA THURSDAY
NIGHT CAUSING MOST OF THE SNOW TO END. NORTHERLY WINDS AND COLD
TEMPERATURES ALOFT WILL KEEP STRONGER SNOW SHOWERS GOING ALONG THE
SOUTH SHORE. SEVERAL MORE INCHES OF SNOW LOOK LIKELY ACROSS
NORTHERN ASHLAND/IRON COUNTIES...WITH SOME LOCALIZED HEAVY AMOUNTS
POSSIBLE.
A WEAK LOW WILL BRING SOME LIGHT SNOW TO PORTIONS OF THE AREA
FRIDAY NIGHT...THEN THE REST OF THE EXTENDED LOOKS RELATIVELY
DRY.
HIGHS THURSDAY WILL BE IN THE TEENS OVER NORTHERN MINNESOTA AND
LOWER TO MID TWENTIES OVER OUR SOUTHERN ZONES...BUT WILL DROP
THROUGH THE DAY OVER MOST OF MINNESOTA. HIGHS FRIDAY WILL ONLY
RANGE FROM 5 TO 15...THEN THEY WILL MODERATE THROUGH THE WEEKEND
REACHING THE TWENTIES FOR MOST AREAS SUNDAY/MONDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 542 AM CST TUE JAN 14 2014
A CLIPPER MOVING INTO SOUTHERN WISCONSIN THIS MORNING WILL
CONTINUE EAST TODAY. SNOW WAS FALLING FROM THE BRAINERD LAKES
REGION EAST INTO NORTHERN WISCONSIN. MVFR/IFR CONDITIONS WERE
OCCURRING DUE TO THE CLIPPER OVER THE SOUTHERN HALF OF THE
NORTHLAND. MORE IFR/MVFR CEILINGS WERE MOVING SOUTH FROM FAR
NORTHERN MINNESOTA AND SOME LIGHT SNOW WILL OCCUR UNDER THESE
CLOUDS. THE MVFR/IFR CEILINGS MOVING SOUTH SHOULD ARRIVE IN KHIB
OVER THE NEXT 2 HOURS...AND IN KDLH IN 3 TO 4 HOURS. OVERALL...WE
EXPECT MVFR/PATCHY IFR CONDITIONS TODAY INTO THIS EVENING.
CONFIDENCE IS LOWER TONIGHT IN HOW QUICKLY THE MVFR CEILINGS WILL
DISSIPATE. AT THIS TIME...WE THINK SKIES WILL SLOWLY CLEAR FROM
WEST TO EAST LATER TONIGHT...WITH MVFR CEILINGS REMAINING OVER
NORTHERN WISCONSIN DUE TO LAKE PROCESSES WITH NORTHERLY WINDS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 14 -2 12 9 / 20 0 70 60
INL 9 -12 16 15 / 10 10 70 70
BRD 16 -5 17 15 / 90 10 80 50
HYR 18 -1 13 11 / 80 20 30 70
ASX 17 1 14 12 / 60 40 20 70
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER WEATHER ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR WIZ009.
LS...NONE.
&&
$$
UPDATE...CANNON
SHORT TERM...GROCHOCINSKI
LONG TERM...MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1038 AM CST TUE JAN 14 2014
.UPDATE...
ISSUED AT 1038 AM CST TUE JAN 14 2014
LATEST SPC MESO ANALYSIS SHOWS AREA OF 85H FRONTOGENESIS IS MOVING
ACROSS SERN CORNER OF CWA. SAT IMAGERY SHOWS CONVECTIVE APPEARANCE
TO CLOUD MASS OVER SERN CWA WITH REPORTED SFC OBS UNDERNEATH OF
1/2SM TO 1 1/2SM VISIBILITY. LATEST HOPWRF AND HRRR 3KM INDICATE 3
TO 5 INCHES SHOULD FALL OVER SRN PRICE COUNTY. A FEW INCHES ARE
EXPECTED OVER EXTREME SRN SAWYER/WASHBURN COUNTY AS WELL.
ELSEWHERE FAIRLY BENIGN PATTERN AS DEEP LAYER COLD ADVECTION
CONTINUES. ONE CHALLENGE TODAY IS CLOUD COVER. SKIES HAVE
PARTIALLY CLEARED IN WRN/NRN CWA SO HAVE LOWERED COVERAGE IN
GRIDS. A SECONDARY SHORTWAVE INDICATED ON RAP40 OVER SRN MANITOBA
...ASSOCIATED WITH CYCLONIC SHEAR FROM UPPER JET...IS MOVING SOUTH
AND HAS SPREAD ANOTHER AREA OF LIGHT SNOW INTO THE NWRN CORNER OF
MN. HAVE INCREASED CLOUDS THIS AFTN OVER WRN CWA AND ADDED
FLURRIES TO ACCOUNT FOR THIS FEATURE. LOWERED MAX TEMPS JUST A
DEGREE OR TWO BASED ON LATEST OBS AND LAV GUIDANCE.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 325 AM CST TUE JAN 14 2014
AT 315AM/0915Z...THERE WAS A CLIPPER SYSTEM MOVING EAST THROUGH
SOUTHERN MINNESOTA. WEAK HIGH PRESSURE WAS CENTERED OVER EASTERN
MANITOBA AND WESTERN ONTARIO. THE CLIPPER SYSTEM HAD A SUBTLE
INVERTED TROUGH EXTENDING TO THE NNW THROUGH THE EASTERN DAKOTAS
AND WESTERN MANITOBA. MUCH OF THE SOUTHERN FORECAST AND SOUTH HAD
CLOUDY SKIES WITH LIGHT TO MODERATE SNOW MOVING THROUGH THE AREA.
THE HEAVIES SNOW WAS GENERALLY SOUTH OF THE FORECAST AREA. THE
NORTHERN FORECAST AREA HAD PARTLY TO MOSTLY CLEAR SKIES. THERE WAS
A BAND OF LOW OVERCAST CLOUDS ALONG AND NEAR THE INVERTED
TROUGH...AND THE BAND WAS PRODUCING LIGHT SNOW IN EASTERN NORTH
DAKOTA AND NW MINNESOTA. THE WINDS WERE CALM ACROSS THE NORTHERN
FORECAST AREA...WHILE THE SOUTHERN FORECAST AREA HAD VERY LIGHT N
TO NNE WINDS. TEMPERATURES RANGED FROM THE LOW 20S IN NW WISCONSIN
UNDER THE CLOUDY SKIES TO THE SINGLE DIGITS AND TEENS BELOW ZERO
ACROSS THE NORTHERN FORECAST AREA UNDER THE CLEAR SKIES.
TODAY...THE CLIPPER SYSTEM WILL BRING LIGHT TO MODERATE SNOW TO
THE SOUTHERN FORECAST AREA. THE LATEST MODELS INDICATED A BIT MORE
SNOW ACROSS THE SOUTH...ENOUGH TO WARRANT A WINTER WEATHER
ADVISORY FOR PRICE COUNTY. THE SOUTHERN HALF OF PRICE COUNTY COULD
SEE ABOUT 2 TO 4 INCHES. AREAS SOUTH OF
HINCKLEY...GRANTSBURG...SPOONER...AND HAYWARD COULD SEE ABOUT 2 TO
3 INCHES IN THEIR RESPECTIVE COUNTIES. THE SNOW WILL BEGIN TO
DIMINISH AND EXIT THE REGION LATE THIS MORNING AND THIS AFTERNOON.
LIGHT SNOW OR FLURRIES COULD CONTINUE ACROSS THE WESTERN FORECAST
AREA DUE TO THE LINGERING INVERTED TROUGH FROM THE CLIPPER OVER
THE NORTHERN PLAINS. HIGH TEMPERATURES SHOULD RANGE FROM THE UPPER
TEENS AND LOW 20S IN NW WISCONSIN TO THE SINGLE DIGITS AND LOW
TEENS ACROSS MOST OF NE MINNESOTA.
TONIGHT...THERE WILL LIKELY BE SOME CLEARING TONIGHT AS A RIDGE OF
HIGH PRESSURE MOVES INTO THE REGION. THE CLEARING AND DECREASING
WINDS WILL HELP TEMPERATURES DROP TO THE SINGLE DIGITS AND LOW
TEENS BELOW ZERO ACROSS MOST OF THE NORTHLAND. THERE MIGHT BE SOME
LIGHT LAKE EFFECT SNOW ALONG AND NEAR THE GOGEBIC RANGE IN IRON
AND ASHLAND COUNTIES DUE TO THE COLD NORTHERLY FLOW OVER WESTERN
LAKE SUPERIOR...BUT LITTLE IF ANY ACCUMULATION IS EXPECTED.
WEDNESDAY...ANOTHER CANADIAN CLIPPER WILL BEGIN TO AFFECT THE
NORTHLAND DURING THE AFTERNOON. IT WILL MOVE NW SASKATCHEWAN
TO CENTRAL MANITOBA BY THE LATE AFTERNOON. IT WILL QUICKLY BRING
LIGHT SNOW TO WESTERN AND MUCH OF THE CENTRAL FORECAST AREA DURING
THE AFTERNOON AHEAD OF ITS APPROACHING WARM FRONT FROM THE WEST. I
INCREASED THE PCPN CHANCES QUITE A BIT BASED ON THE LATEST MODELS
BEING IN PRETTY GOOD AGREEMENT. I LEANED ON THE SREF FOR THOSE
PCPN CHANCES. MUCH OF NE MINNESOTA WILL GET ABOUT A HALF TO 1.5
INCHES BY THE EVENING. SNOW WILL CONTINUE WEDNESDAY NIGHT. I
INCLUDED A SLIGHT CHANCE OF FREEZING DRIZZLE FOR THE BRAINERD
LAKES AREA DURING THE LATE AFTERNOON. IT LOOKS LIKE THE ONSET OF
THE PCPN WILL BE SNOW DUE TO SATURATION TO THE UPPER LEVELS...BUT
ONCE THE INITIAL MAIN BAND OF SNOW MOVES THROUGH...THE MID AND
UPPER LEVEL SATURATION COULD BE LOST...LEAVING A RELATIVELY WARM
LOW LEVEL SATURATED LAYER WITH LITTLE POTENTIAL FOR ICE CRYSTAL
NUCLEATION FOR SNOW.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 325 AM CST TUE JAN 14 2014
EMPHASIS IN THE EXTENDED PERIOD WILL BE EARLY AND REVOLVE AROUND
SNOW AND WIND WITH A STRONG AREA OF LOW PRESSURE THAT WILL MOVE
FROM MANITOBA WEDNESDAY EVENING TO THE EASTERN LAKE
SUPERIOR/NORTHERN MICHIGAN AREA BY THURSDAY EVENING.
STRONG WAA WILL MOVE WEST TO EAST THROUGH THE NORTHLAND WEDNESDAY
NIGHT ALONG WITH A POTENT SHORTWAVE. STRONG CAA WILL MOVE
QUICKLY INTO NORTHERN MINNESOTA LATE WEDNESDAY NIGHT. AN AREA OF
SNOW WILL OCCUR IN RESPONSE TO THE WAA/SHORTWAVE AND WE HAVE
SNOWFALL JUST WEDNESDAY NIGHT FROM A HALF TO AROUND 3
INCHES...WITH THE HIGHEST AMOUNTS MOST LIKELY ACROSS THE
ARROWHEAD...AND THE BRAINERD LAKES REGION SEEING THE LOWER
AMOUNTS. SOUNDINGS SUGGEST SOME FREEZING DRIZZLE WILL ALSO BE
POSSIBLE THROUGH AT LEAST MIDNIGHT OVER THE SOUTHERN HALF TO TWO
THIRDS OF THE NORTHLAND AS DEEPER MOISTURE MOVES EAST. ALTHOUGH
THE MODELS ARE IN DECENT AGREEMENT...THERE DOES REMAIN SOME ISSUES
ON TIMING...STRENGTH...AND EXACT TRACK OF THE LOW. THIS WILL PLAY
A CRITICAL ROLE IN HOW STRONG THE WINDS GET AND WHEN THE PEAK WIND
PERIOD WILL OCCUR. WE EXPECT WINDS TO INCREASE OUT OF THE WEST-
NORTHWEST LATE WEDNESDAY NIGHT...MAINLY OVER THE WESTERN
HALF...THEN INCREASE FURTHER THROUGH THE DAY THURSDAY.
TEMPERATURES WILL LIKELY RISE WEDNESDAY NIGHT...WITH THEM DROPPING
THROUGH THE DAY OVER MOST OF MINNESOTA DUE TO THE STRONG CAA.
PERIODS OF SNOW WILL CONTINUE TO BE POSSIBLE THURSDAY AS ANOTHER
POTENT SHORTWAVE MOVES THROUGH THE NORTHLAND. MOST AREAS THURSDAY
SHOULD ONLY SEE LIGHT SNOW ACCUMULATIONS. THE SNOWBELT OF THE
SOUTH SHORE OF LAKE SUPERIOR...MAINLY ASHLAND/IRON COUNTIES...WILL
SEE LAKE EFFECT SNOW SHOWERS INCREASE THROUGH THE DAY
THURSDAY...WITH SEVERAL INCHES POSSIBLE.
A RIDGE OF HIGH PRESSURE WILL MOVE INTO WESTERN MINNESOTA THURSDAY
NIGHT CAUSING MOST OF THE SNOW TO END. NORTHERLY WINDS AND COLD
TEMPERATURES ALOFT WILL KEEP STRONGER SNOW SHOWERS GOING ALONG THE
SOUTH SHORE. SEVERAL MORE INCHES OF SNOW LOOK LIKELY ACROSS
NORTHERN ASHLAND/IRON COUNTIES...WITH SOME LOCALIZED HEAVY AMOUNTS
POSSIBLE.
A WEAK LOW WILL BRING SOME LIGHT SNOW TO PORTIONS OF THE AREA
FRIDAY NIGHT...THEN THE REST OF THE EXTENDED LOOKS RELATIVELY
DRY.
HIGHS THURSDAY WILL BE IN THE TEENS OVER NORTHERN MINNESOTA AND
LOWER TO MID TWENTIES OVER OUR SOUTHERN ZONES...BUT WILL DROP
THROUGH THE DAY OVER MOST OF MINNESOTA. HIGHS FRIDAY WILL ONLY
RANGE FROM 5 TO 15...THEN THEY WILL MODERATE THROUGH THE WEEKEND
REACHING THE TWENTIES FOR MOST AREAS SUNDAY/MONDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 542 AM CST TUE JAN 14 2014
A CLIPPER MOVING INTO SOUTHERN WISCONSIN THIS MORNING WILL
CONTINUE EAST TODAY. SNOW WAS FALLING FROM THE BRAINERD LAKES
REGION EAST INTO NORTHERN WISCONSIN. MVFR/IFR CONDITIONS WERE
OCCURRING DUE TO THE CLIPPER OVER THE SOUTHERN HALF OF THE
NORTHLAND. MORE IFR/MVFR CEILINGS WERE MOVING SOUTH FROM FAR
NORTHERN MINNESOTA AND SOME LIGHT SNOW WILL OCCUR UNDER THESE
CLOUDS. THE MVFR/IFR CEILINGS MOVING SOUTH SHOULD ARRIVE IN KHIB
OVER THE NEXT 2 HOURS...AND IN KDLH IN 3 TO 4 HOURS. OVERALL...WE
EXPECT MVFR/PATCHY IFR CONDITIONS TODAY INTO THIS EVENING.
CONFIDENCE IS LOWER TONIGHT IN HOW QUICKLY THE MVFR CEILINGS WILL
DISSIPATE. AT THIS TIME...WE THINK SKIES WILL SLOWLY CLEAR FROM
WEST TO EAST LATER TONIGHT...WITH MVFR CEILINGS REMAINING OVER
NORTHERN WISCONSIN DUE TO LAKE PROCESSES WITH NORTHERLY WINDS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 14 -2 12 9 / 20 0 70 60
INL 9 -12 16 15 / 10 0 70 70
BRD 16 -5 17 15 / 90 10 80 50
HYR 18 -1 13 11 / 80 10 30 70
ASX 17 1 14 12 / 40 20 20 70
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER WEATHER ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR WIZ009.
LS...NONE.
&&
$$
UPDATE...CANNON
SHORT TERM...GROCHOCINSKI
LONG TERM...MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
1052 AM MST TUE JAN 14 2014
.UPDATE...
SNOWFALL HAS ENDED ACROSS THE BEARTOOTH AND RED LODGE FOOTHILLS
AREAS WITH JUST A FEW ISOLATED SNOW SHOWERS REMAINING. WEBCAMS
CURRENTLY SHOWING PARTLY SUNNY SKIES ACROSS MANY LOCATIONS.
HOWEVER...AN UNSTABLE NORTHWEST FLOW ALOFT CONTINUES TO PRODUCE
SNOW SHOWERS...SOME HEAVY...ACROSS BIG HORN AND SHERIDAN COUNTIES.
HOWEVER...WITH WARMING TEMPERATURES...ADDITIONAL ACCUMULATIONS ARE
ONLY EXPECTED TO BE ABOUT AN INCH OR TWO FOR THESE AREAS WITH
ANOTHER 2 OR 3 INCHES POSSIBLE FOR THE BIG HORN MOUNTAINS.
THEREFORE...HAVE LET ALL WINTER HIGHLIGHTS EXPIRE AT 10AM EXCEPT
FOR THE BIG HORN MOUNTAINS AND WILL CONTINUE THAT WINTER WEATHER
ADVISORY UNTIL 5PM. UPDATED FORECAST HAS BEEN ISSUED. HOOLEY
&&
.SHORT TERM...VALID FOR TDY AND WED...
MOIST NORTHWESTERLY FLOW ALOFT WITH ROOTS IN A PINEAPPLE
CONNECTION IS BEING REAL EFFICIENT AND PRODUCING SO FOR SOUTHERN
PORTIONS OF SOUTH CENTRAL MONTANA AND NORTHERN WYOMING. BAND IS
ORIENTED NORTHWEST TO SOUTHEAST AN IS MOST INTENSE OVER STILLWATER
AND CARBON COUNTIES WHERE SOME WARM AIR ADVECTION IS BEGINNING TO
NUDGE THE COLD FRONT BACK TO THE EAST. THIS CAN BE SEEN AS
BILLINGS PRESSURE IS RISING LIVINGSTON IS FALLING...SO
FRONTOGENESIS IS PICKING ALONG THE BAND...WHICH IS ALSO AIDED BY
SOME UPSLOPE INTO THE PRYOR MOUNTAINS AND BEARTOOTH AND RED LODGE
FOOTHILLS.
FIRST FORECAST CHALLENGE IS HOW FAST DOES THIS BAND MIGRATE
EASTWARD BEFORE RISING HEIGHTS STABILIZE THE AIRMASS TOO MUCH AND
DOWNSLOPE ERODES THE PRECIPITATION. RUC MODEL IS THE ONLY ONE THAT
REALLY TRACKED THE PRECIP WELL EARLIER AND IT SHIFTS THE AXIS INTO
YELLOWSTONE AND BIG HORN COUNTIES FOR A FEW HOURS THIS MORNING
BEFORE IT BEGINS TO WANE. THIS SEEMS TO REFLECT CURRENT RADAR
TRENDS SO INCREASING POPS FOR THE CENTRAL ZONES. JUST GOT REPORT
OF 12 TO 16 INCHES OF SNOW IN RED LODGE AND GIVEN CURRENT RADAR
TRENDS WILL UPGRADE RED LODGE FOOTHILLS AND EASTERN CARBON COUNTY
TO A WINTER STORM WARMING. WILL EXTEND THE WINTER WEATHER ADVISORY
FOR BIG HORN AND SHERIDAN COUNTY WYOMING UNTIL 10 AM. EXPECT AN
INCH POSSIBLE IN BILLINGS AND AN ADDITIONAL COUPLE OF INCHES FOR
THE ADVISORY LOCATIONS AND ANOTHER 3 FOR THE WARNING AREA.
PROBABLY SOME AREAS OF BLOWING AND DRIFTING DUE TO WINDS ABOVE 20
MPH BUT EARLY SPOTTER REPORTS SAY IT WAS STICKY AND NOT REALLY
MOVING.
OTHERWISE AS LEESIDE TROUGHING WINDS INCREASE...TEMPERATURES
INCREASE AND PRECIPITATION DECREASES. WEDNESDAY WILL BE A WINDY
DAY BUT ANY FRONTAL PUSH LOOKS TO BE LATER AT NIGHT...SO NOT
CONCERNED ABOUT LOW ELEVATION WINDS. LOOKS LIKE WIND ADVISORY MAY
BE NEEDED FOR GAP FLOW AREAS BUT WILL WAIT FOR ANOTHER ROUND OF
MODELS TO DECIDE. BORSUM
.LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON...
DRY NW FLOW ON THE E SIDE OF AN UPPER RIDGE WILL BE OVER THE
FORECAST AREA INTO SAT. HEIGHTS BEGIN TO FALL ON SUN IN RESPONSE
TO A WEAK WAVE MOVING THROUGH THE FLOW. HOWEVER...AIRMASS LOOKED
DRIER THAN IN PREVIOUS MODEL RUNS SO HAVE LIMITED LOW POPS TO JUST
THE MOUNTAINS. GFS HAD A SHORTWAVE APPROACHING THE AREA ON MON
FROM THE N WHILE ECMWF MAINTAINED A QUIETER NW FLOW. FOR
NOW...JUST HAD SOME MOUNTAIN POPS FOR MON. A DRY NW FLOW
PREVAILED ON TUE. THERE WILL BE PERIODS OF LEE TROUGHINESS
THROUGH THE EXTENDED WHICH WILL PRODUCE GUSTY WINDS IN THE GAP
FLOW AREAS AND BIG TIMBER. TEMPERATURES WILL BE ABOVE SEASONAL
VALUES THROUGH THE PERIOD AND MADE SOME ADJUSTMENTS TO THEM BASED
ON LATEST GUIDANCE. ARTHUR
&&
.AVIATION...
MVFR TO IFR CONDITIONS WILL AFFECT AREAS FROM E OF KLVM TO SW OF
KMLS...INCLUDING NEAR KBIL AND KSHR...OVER THE NEXT FEW HOURS.
LOCALIZED LIFR CONDITIONS ARE POSSIBLE. CONDITIONS WILL GRADUALLY
IMPROVE TO VFR IN THAT REGION THROUGH EARLY THIS AFTERNOON. MVFR
CIGS AND A FEW SNOW SHOWERS MAY ALSO IMPACT AVIATION ACROSS THE
EAST...INCLUDING BAKER...THROUGH THE DAY. EXPECT MOUNTAIN
OBSCURATION INTO THIS AFTERNOON.
WEST TO SOUTHWEST WINDS WILL BECOME STRONG AND GUSTY AGAIN THIS
AFTERNOON ACROSS WESTERN ROUTES...INCLUDING KLVM AND BIG TIMBER.
THE STRONG...GUSTY WINDS WILL CONTINUE OVERNIGHT. STC
&&
.PRELIMINARY POINT TEMP/POPS...
TDY WED THU FRI SAT SUN MON
-------------------------------------------------------
BIL 042 031/051 028/041 030/049 028/050 032/047 028/044
7/N 11/N 10/B 00/U 00/U 01/U 11/B
LVM 042 034/049 030/040 030/047 033/047 038/046 032/043
1/N 11/N 10/B 00/N 00/U 01/N 11/B
HDN 039 023/049 023/039 020/045 018/048 022/043 019/040
6/B 11/N 00/U 00/U 00/U 01/U 11/B
MLS 034 025/044 022/034 019/041 020/040 022/040 018/035
1/B 11/N 10/N 00/B 00/U 01/U 11/B
4BQ 034 025/048 024/034 019/042 018/042 024/043 020/039
4/B 01/N 00/N 00/B 00/U 01/U 11/U
BHK 031 024/045 020/027 018/037 017/039 022/041 017/034
1/B 11/N 11/N 00/B 00/B 01/U 11/B
SHR 037 023/050 022/038 020/045 023/047 023/047 022/044
8/W 01/U 10/B 00/B 00/U 00/U 10/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...WINTER WEATHER ADVISORY IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON FOR ZONE 98.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
334 PM EST TUE JAN 14 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE OFF THE COAST THIS EVENING FOLLOWED BY
ANOTHER COLD FRONT WEDNESDAY NIGHT. A STRONGER COLD FRONT WILL
CROSS THE AREA LATE FRIDAY FOLLOWED BY A REINFORCING SHOT OF COLD
AIR ON SUNDAY. DRY HIGH PRESSURE WILL BUILD INTO THE AREA EARLY
NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM TUESDAY...THE COLD FRONT CONTINUES TO PRESS EASTWARD AS IT
IS APPROACHES RALEIGH BUT IS IT STILL LAGS A BIT TO THE SOUTH. A
POSSIBLE PREFRONTAL TROUGH IS RUNNING AHEAD OF THE FRONT TO THE
SOUTH. THE 18Z UTC RUC IS SHOWING THE 850 LOW LEVEL JET MAX CENTERED
OVER SOUTH CAROLINA AND THIS FEATURE WILL SHIFT NORTH OUT OF THE
AREA BY 22 UTC. THIS APPEARS TO BE THE WHAT IS ENHANCING THE LOW TOP
CONVECTION IN INLAND AREAS OF SOUTHEAST NORTH CAROLINA.
SEA FOG IS NOW BREAKING UP ALONG THE GEORGETOWN COAST AND WILL
LINGER FOR THE NEXT HALF HOUR BEFORE BECOMING A NONE FACTOR.
MODELS STILL CONTINUE TO BRING A FRONT TO THE COAST BY 7 PM BUT THE
MODELS MAINTAIN A GOOD CHANCE OF SHOWERS EARLY THEN SLOWLY TAPER THE
RAIN OFF OVERNIGHT. QPF VALUES APPEAR TO BE LESS THAN A HALF OF AN
INCH.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 PM TUESDAY...WILL A LITTLE SNOW FALL EARLY THURS OR
NOT IS THE QUESTION...
A WAVE OF LOW PRESSURE WILL MOVE UP ALONG COLD FRONT WELL OFF
SHORE IN DEEP SW FLOW AHEAD OF DEEPENING TROUGH DIGGING DOWN FROM
THE GREAT LAKES TOWARD THE GULF COAST ON WED. EXPECT SUNNY AND DRY
WEATHER AHEAD OF THIS SYSTEM WITH TEMPS UP CLOSER TO 60 BUT THIS
TROUGH WILL ADVANCE EASTWARD THROUGH WEDNESDAY PUSHING ANOTHER
COLD FRONT INTO AND THROUGH THE CAROLINAS WED NIGHT. A POTENT VORT
MAX WILL RIDE THROUGH THE CAROLINAS AS THE TROUGH LIFTS TOWARD THE
NORTHEAST THROUGH EARLY THURS. THIS SHOULD HELP TO SQUEEZE OUT ANY
AVAILABLE MOISTURE IN THE ATMOSPHERE WITH BEST UPWARD VV WITHIN
THE FEW HOURS SURROUNDING DAYBREAK. BY NOON ON THURS ALL PCP
SHOULD MOVE OFF SHORE. PCP WATER VALUES WILL BE RIGHT AROUND A
HALF INCH WITH MOISTURE PROFILES SHOWING BEST SATURATION IN THE
LAYER BETWEEN BETWEEN 1500 FT AND 5K FT THROUGH THURS MORNING.
OVERALL NOT MUCH MOISTURE TO WORK WITH AND BORDERLINE TEMP
PROFILES UP THROUGH THE ATMOSPHERE TO PRODUCE SNOW.
IT WILL BE TRICKY AS TO HOW FAST THE COLD AIR MOVES IN VS. HOW
MUCH LINGERING MOISTURE THERE IS TO SQUEEZE OUT. SFC FRONT BRINGS
COOLER AIR IN AFTER MIDNIGHT AT THE SURFACE BUT WARM NOSE ALOFT
STILL EVIDENT THROUGH EARLY MORNING WITH CAA INCREASING THROUGH
LATE MORNING AS WINDS SHIFT AROUND TO THE NW ALOFT...BUT THIS WILL
ALSO INCREASE DRYING THROUGH THE AFTERNOON...PLUS DIURNAL WARMING
WILL OCCUR. THEREFORE THERE WILL BE A VERY SMALL WINDOW OF
OPPORTUNITY FOR ANY MIXED PCP OR SNOW TO FALL...ESPECIALLY ALONG
THE COAST. INLAND WILL HAVE A SLIGHTLY BETTER CHC AS THEY WILL SEE
COOLER AIR MOVE IN ALOFT BEFORE DAYBREAK WHICH SHOULD ALLOW FOR
SOME LIGHT SNOW.
SURFACE WET BULB TEMPS REMAIN RIGHT AROUND FREEZING AND DEWPOINT
TEMPS WILL BE DROPPING THROUGH THE EARLY MORNING HOURS REACHING
BELOW FREEZING INLAND SEVERAL HOURS BEFORE DAYBREAK BUT JUST
AROUND DAYBREAK CLOSE TO THE COAST. THEREFORE WITH EVAPORATIVE
COOLING TAKEN INTO EFFECT...WOULD SAY LIKELIHOOD OF ANY MIXED PCP
WILL BE INLAND. FOR NOW WILL INCLUDE SOME MIXED PCP INLAND BUT
WILL KEEP RAIN ALONG THE COAST...BUT WOULD NOT DISCOUNT SOME SNOW
MIXING IN BEFORE IT ALL ENDS. ALL PCP WILL END BY NOON AS SUBSIDENCE
AND FURTHER DRYING OCCURS ON BACK END OF SYSTEM AND TEMPS REACH
UP CLOSE TO 40 DEGREES. CLEARING WILL OCCUR THROUGH LATE WEDNESDAY
WITH TEMPS DROPPING INTO THE LOW TO MID 30S.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 300 PM TUESDAY...DEEP LONGWAVE TROUGH TO PLAGUE THE EAST COAST
ONCE AGAIN FOR THE FIRST HALF OF THE EXTENDED. THICKNESSES ARE
EXPECTED TO INCREASE EARLY NEXT WEEK...BEFORE COLD TROUGH RELOADS
ONCE AGAIN AND PUSHES SOUTH BY THE END OF THE PERIOD.
FAST AND ACTIVE FLOW CONTINUES...IN A PATTERN THAT HAS PERSISTED THE
ENTIRE WINTER THUS FAR. DEEP LONGWAVE TROUGH WILL HAVE ITS AXIS WEST
OF THE LOCAL AREA AT THE START OF THE PERIOD...WITH A STRONG VORT
SWINGING THROUGH THE BASE BY SATURDAY MORNING. THIS DRIVES A COLD
FRONT ACROSS THE CAROLINAS...AND ALTHOUGH GUIDANCE HINTS AT SOME
PRECIP FRIDAY NIGHT...PLAN TO KEEP INHERITED DRY FORECAST AS THETA-E
RIDGE REMAINS DISPLACED OFFSHORE AND PWATS ARE QUITE LOW. BIGGER
IMPACT WILL BE STRONG CAA...WITH 850MB TEMPS DROPPING TO AROUND -10C
EARLY SATURDAY MORNING. CANADIAN HIGH PRESSURE BUILDS INTO THE AREA
BEHIND THIS FRONT...COINCIDENT WITH THE UPPER TROUGH RELOADING AS A
SECOND VORT SWINGS THROUGH...WITH THE BEST FORCING AGAIN REMAINING
NORTH OF THE LOCAL AREA. THIS SUGGESTS TEMPS WELL BELOW CLIMO FOR
THE WKND...AS ANOTHER REINFORCING SHOT OF COLD AIR OCCURS LATE
SUNDAY. ONCE AGAIN...DO NOT ANTICIPATE ANY PRECIP WITH THESE
FEATURES...BUT WINTRY PRECIP WON`T BE TOO FAR REMOVED TO THE NORTH.
MORE SEASONABLE WEATHER EXPECTED FOR EARLY WEEK AS A RENEWED TROUGH
BEGINS TO DIVE INTO THE MIDDLE PART OF THE COUNTRY...DRIVING
DOWNSTREAM RIDGING ACROSS THE EAST. THIS PUSHES THE HIGH PRESSURE
OFFSHORE...WHICH...ALTHOUGH IT WEAKENS CREATING A RATHER DIFFUSE
PRESSURE GRADIENT...STILL PROMOTES SW RETURN FLOW AND TEMPS RISING
TO CLIMO OR SLIGHTLY ABOVE MON/TUE. THIS SETS THE STAGE FOR BETTER
PRECIP CHANCES BEGINNING AT THE END OF THE PERIOD AS ANOTHER
SHORTWAVE DIVES ACROSS THE AREA.
&&
.AVIATION /18Z TUESDAY THROUGH SATURDAY/...
AS OF 18Z...LOOK FOR IFR CONDITIONS INLAND AT THE ONSET...WITH
MAINLY MVFR CONDITIONS ALONG THE COAST. PRECIPITATION WILL SLOWLY
END FROM WEST TO EAST AS THE COLD FRONT MOVES THROUGH. WINDS WILL
SHIFT TO THE WEST BY MID AFTERNOON...POST FRONTAL. WITH ALL THE LOW
LEVEL MOISTURE AND FAIRLY LIGHT WINDS TONIGHT...FOG IS A GOOD
POSSIBILITY. WILL GO WITH MAINLY IFR...HOWEVER LIFR IS A REASONABLE
POSSIBILITY...PARTICULARLY IF THE CIRRUS BECOMES SCATTERED.
WEDNESDAY...A NICE DAY ONCE THE FOG MIXES OUT WHICH SHOULD BE FAIRLY
QUICK AFTER SUNRISE. NOT MUCH IN THE WAY OF A PRESSURE GRADIENT SO
LOOK FOR LIGHT AND VARIABLE WINDS WEDNESDAY.
EXTENDED OUTLOOK...A SLIGHT CHANCE OF PRECIP THURSDAY
MORNING...OTHERWISE VFR CONDITIONS THROUGH THE FORECAST PERIOD.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM TUESDAY...THE DENSE FOG ADVISORY WILL BE ALLOWED TO
EXPIRE AT 3 PM AS IT CONTINUE TO SLOWLY DISSIPATE AND ADVECT TO
THE NORTH NORTHEAST AHEAD OF A SLOW MOVING FRONT FOR THE WATERS
MAINLY SOUTH OF LITTLE RIVER INLET.
THE FRONTAL PASSAGE ACROSS THE WATERS IS EXPECTED AFTER 7 PM AND
WITH THIS FRONT A GOOD PUSH OF OFFSHORE FLOW IS EXPECTED AND THE
SEAS WILL FALL BELOW SMALL CRAFT CONDITIONS AT 8 PM SOUTH OF LITTLE
RIVER INLET AND 2 AM FOR THE WATERS TO THE NORTH. SEAS SHOULD RELAX
LATE AND WILL BEGIN AT 4 TO 6 FEET BUT WILL SETTLE OUT TO A RANGE
OF 2 FEET NEAR SHORE AND 5 FEET AT 20 MILES OFF THE COAST.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 PM TUESDAY...WILL BE IN BETWEEN TWO FRONTS ON WED WITH
ONE EXITING FURTHER INTO THE ATLANTIC AND ONE MARCHING EAST TOWARD
THE CAROLINAS. WINDS WILL BACK AROUND ON WEDNESDAY WITH LIGHT W-SW
WINDS TO START. AS THE DAY PROGRESSES WINDS WILL INCREASE TO
15-20 KNOTS AS A COLD FRONT APPROACHES. THIS FRONT WILL MOVE
ACROSS THE WATERS AFTER MIDNIGHT WED NIGHT INTO EARLY THURS
MORNING WITH WINDS VEERING AROUND TO THE NORTHWEST UP NEAR 20
KTS. A VERY PROGRESSIVE FLOW CONTINUES WITH WINDS BACKING TO THE
WEST AS YET ANOTHER FRONT APPROACHES THE CAROLINAS ON FRIDAY. SEAS
WILL REMAIN FAIRLY BENIGN WITH 1 TO 3 FT SEAS INCREASING TO 2-4
FEET BY WED NIGHT INTO THURS. MAY SEE A FEW 5 FTERS IN OUTER
WATERS AS WINDS SPIKE UP ON THURS. A SHARP RISE WILL BEGIN JUST AT
THE END OF THE SHORT TERM PERIOD.
LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 300 PM TUESDAY...TWO COLD FRONTS WILL CROSS THE WATERS
DURING THE PERIOD...ONE SATURDAY MORNING...AND ANOTHER SUNDAY EVE.
THIS CREATES TWO PERIODS OF INCREASED WINDS...AND MUCH OF THE
PERIOD WILL FEATURE UNSETTLED MARINE CONDITIONS. AHEAD OF THE
FIRST FRONT ON FRIDAY...SW WINDS WILL INCREASE TO 15-25 KTS FRIDAY
NIGHT...DRIVING SEAS UP TO 4-7 FT...AND A SMALL CRAFT ADVISORY
WILL LIKELY BE NEEDED FRIDAY INTO SATURDAY. COLD FRONT CROSSES
OVERNIGHT INTO SATURDAY MORNING...TURNING WINDS TO THE NW AT 15-25
KTS BEFORE EASING THROUGH SATURDAY...AND THE HIGHEST SEAS GET
PUSHED AWAY FROM SHORE. THIS LEAVES 2-4 FT SEAS MUCH OF SATURDAY.
WINDS BACK TO THE WEST AGAIN ON SUNDAY AND INCREASE TO 15-20 KTS
AHEAD OF THE NEXT...WEAKER...COLD FRONT LATE IN THE DAY...WHICH
AGAIN TURNS WINDS TO THE NW AT THE END OF THE PERIOD. SEAS WILL
BUILD AGAIN TO 3-5 FT DURING SUNDAY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EST THIS EVENING FOR AMZ250-
252.
&&
$$
NEAR TERM...DRH
SHORT TERM...RGZ
LONG TERM...JDW
AVIATION...DL/DRH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1257 PM EST TUE JAN 14 2014
.SYNOPSIS...AS LOW PRESSURE MOVES AWAY FROM THE CAROLINAS...HIGH
PRESSURE BRIEFLY BUILDS INTO THE REGION THIS EVENING. A COLD FRONT
APPROACHES FROM THE WEST LATE TONIGHT AND EARLY WEDNESDAY...SLOWING
OVER THE CAROLINAS AS ANOTHER LOW PRESSURE SYSTEM STRENGTHENS OFF
THE COAST. HIGH PRESSURE BRIEFLY BUILDS INTO THE REGION ONCE AGAIN
ON THURSDAY...WITH ANOTHER COLD FRONT TO FOLLOW FOR THE END OF THE
WEEK.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 925 AM TUESDAY...
WATER VAPOR IMAGERY SHOWED A MODERATELY STRONG MID-LEVEL SHORTWAVE
MOVING THROUGH THE EASTERN CAROLINAS IN A SOUTHWEST FLOW ALOFT...
AHEAD OF A 100KT 500MB JET THAT PUSHES ACROSS CENTRAL NORTH CAROLINA
DURING THE DAY. A MID-LEVEL TROUGH WITH A DRY PUNCH WAS MOVING EAST
ACROSS TENNESSEE AND APPROACHING THE FAR WESTERN PART OF THE STATE...
AND THIS DRY AIR WILL GRADUALLY MOVE ACROSS THE STATE DURING THIS
AFTERNOON. IN THE MEANTIME...THE 12Z KGSO SOUNDING INDICATED DEEP
MOISTURE WITH GOOD LOW-LEVEL MOISTURE TRANSPORT AND LIFT...PARTLY
NOTED BY 850MB WINDS GREATER THAN WHAT THE RAP WAS FORECASTING EARLY
THIS MORNING...AROUND 40KT. AS THE LIFTING SYNOPTIC FEATURES MOVE
EAST AND NORTHEAST...DRIER AIR SHOULD GRADUALLY MOVE ACROSS CENTRAL
NORTH CAROLINA THIS AFTERNOON. K INDICES ARE NEGATIVE BY 23Z EVEN AS
FAR EAST AS THE COASTAL PLAIN...WITH PRECIPITABLE WATER VALUES
FALLING TO 0.75 INCH OR LESS BY 00Z. LOOKING AT THE TIMING OF THE
DRIER AIR COMBINED WITH THE HRRR WRF RAINFALL FORECAST WOULD
INDICATE PERIODS OF RAIN AND DRIZZLE DRYING IN THE TRIAD AROUND
18Z...IN THE TRIANGLE AND FAYETTEVILLE BETWEEN 19Z AND 2030Z...AND
IN THE EASTERN COASTAL PLAIN BY 22Z. CLEARING MAY BE DELAYED FROM
THAT ABOUT AN HOUR...BUT IT SHOULD BE CLOSE. DID NOT MODIFY
TEMPERATURES MUCH...MAYBE A DEGREE LOWER...DUE TO THE ALREADY WARM
VALUES MOSTLY ONLY A CATEGORY OR TWO BELOW FORECAST MAXIMUMS. MOSTLY
CLEAR CONDITIONS FOR MUCH OF THE NIGHT WILL SUPPORT LOWS IN THE 30S.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 305 AM TUESDAY...
A SERIES OF STRONG SHORTWAVE TROUGHS WILL DIG SOUTHEASTWARD AND
AMPLIFY THE MEAN MID-UPPER TROUGH ACROSS THE SOUTHEAST STATES
THROUGH WED NIGHT. AN ARCTIC COLD FRONT...WHOSE EASTWARD PROGRESS
HAS TRENDED SLOWER IN NWP GUIDANCE OVER THE PAST COUPLE OF
DAYS...WILL ACCOMPANY THE TROUGH ALOFT...AND IS NOW FORECAST TO
CROSS CENTRAL NC DURING THE EVENING AND OVERNIGHT HOURS WED. THIS
SLOWER SOLUTION...AS THE LEAD SHORTWAVE IN THE SERIES TURNS NNE UP
THE SPINE OF THE APPALACHIANS AND WAITS FOR UPSTREAM ENERGY TO PUSH
THE TROUGH EASTWARD...WILL ALLOW TEMPERATURES TO WARM INTO THE
50S...WITH SKY COVER MOSTLY SUNNY EAST TO BECOMING PARTLY CLOUDY
WEST.
THE FORECAST - A BELOW AVERAGE ONE GIVEN CONTINUED LARGER THAN AVG
MODEL SPREAD - GETS MORE INTERESTING WED NIGHT...AS THE
AFOREMENTIONED SHORTWAVE ENERGY AND ASSOCIATED 150-180 METERS MID
LEVEL HEIGHT FALLS DIG ACROSS THE SAVANNAH BASIN AND OFFSHORE THE SC
COAST - A TRACK FAVORABLE FOR "NW FLOW" PRECIPITATION (NORTH OF THE
VORT TRACK) ACROSS NC. WHILE NWP GUIDANCE SUGGESTS A WEAK/OPEN
SURFACE WAVE MAY ACCOMPANY THE ARCTIC BOUNDARY ACROSS NC...SOME
DEGREE OF COASTAL DEVELOPMENT IS LIKELY AS AS THE STRONG FORCING FOR
ASCENT OVERSPREADS THE GULF STREAM AND LINGERING BAROCLINIC ZONE
JUST OFFSHORE - THE ONE THAT CROSSES OUR REGION TODAY. NWP GUIDANCE
HAS HAD A DIFFICULT TIME WITH BOTH THE TIMING/AMPLITUDE OF THE
APPROACHING SHORTWAVE TROUGHS...AS WELL AS UPON WHICH BOUNDARY - THE
QUASI-STATIONARY OFFSHORE ONE OR CROSSING ARCTIC ONE - THE PRIMARY
LOW DEVELOPS. THIS REMAINING QUESTION WILL HAVE RAMIFICATIONS ON
DURATION AND INLAND-EXTENT OF PRECIPITATION...WHOSE TYPE WOULD
TRANSITION FROM RAIN TO SNOW AS THE DEEP LAYER COOLING CRASHES COAST-
WARD PER BOTH PARTIAL THICKNESSES AND NAM BUFR SOUNDINGS WHOSE
PARENT MASS FIELDS AND QPF OF UP TO A TENTH OF AN INCH LIQUID
EQUIVALENT...CLOSELY RESEMBLE THE PREFERRED ECMWF/EC ENSEMBLE MEAN.
IN THIS LOW CONFIDENCE FORECAST...WILL INCREASE POPS INTO THE CHANCE
RANGE FROM WEST TO EAST DURING THE OVERNIGHT-EARLY THU HOURS...WITH
WORDING OF RAIN CHANGING TO SNOW. PRECIPITATION AMOUNTS WOULD LIKELY
BE LIGHT IN EITHER SCENARIO...SINCE AN UPSTREAM KICKER SHORTWAVE
WOULD LEAVE LITTLE TIME FOR THE OFFSHORE LOW TO LINGER OFF THE NC
COAST. THE CHANCE OF LIGHT SNOW WILL BE ADDED TO THE HWO LATER THIS
MORNING....THOUGH ASSOCIATED IMPACTS AT THIS TIME APPEAR TO BE VERY
MINIMAL. LOW TEMPERATURES CRASHING INTO THE 20S...USHERED IN BY A
BREEZY NW WIND...WITH GUSTS 20-30 MPH POSSIBLE.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 320 AM TUESDAY...
STRONGLY PROGRESSIVE NORTHWEST...SPLIT FLOW ALOFT WILL PREVAIL
THROUGH AT LEAST EARLY NEXT WEEK...AS A STRONG WESTERN RIDGE AND
EASTERN TROUGH PERSIST IN THE MEANS...WITH AN UNDERCUTTING SOUTHERN
STREAM ACROSS THE GOM AND SW ATLANTIC. IN THIS PATTERN...A VIGOROUS
SHORTWAVE TROUGH IN NW FLOW ALOFT AND ACCOMPANYING SURFACE FRONTAL
WAVE/SYSTEM WILL AFFECT CENTRAL NC EVERY COUPLE OF DAYS...WITH
PRONOUNCED BUT SHORT-LIVED POST-FRONTAL COLD...FOLLOWED BY ALSO
BRIEF PRE-FRONTAL MODIFICATION.
AS SUCH...THU WILL BE GENERALLY CLEAR AND CHILLY BETWEEN 40-45
DEGREES...FOLWITH A MOIST AIRMASS IN PLACE AND PERTURBATIONS MOVING
THROUGH IN
THE SOUTHWESTERLY FLOW... LIGHT SHOWERS ARE ONGOING ACROSS THE AREA.
THERE SHOULD BE AN INCREASE IN COVERAGE THROUGH THE MORNING AS THE
DEAMPLIFYING SHORTWAVE CROSSES THE AREA... AND LIFT IS ENHANCED BY
THE RIGHT ENTRANCE REGION OF THE JET. COLD FRONT WILL ENTER WESTERN
PART OF THE CWA AROUND 15Z... AND CLEAR THE CAROLINA COAST BY 00Z.
WINDS WILL BECOME WESTERLY AFTER THE FRONT PASSES... AND DRY AIR
MOVES IN TO THE AREA LATE TUESDAY INTO WEDNESDAY... WITH SKIES
BECOMING MOSTLY CLEAR. WITH A PERIOD OF SUN DURING THE AFTERNOON IN
THE WEST... HIGH TEMPERATURES WILL BE IN THE UPPER 50S. A MILD START
WILL LEAD TO HIGH TEMPERATURES IN THE LOW 60S IN THE EAST... DESPITE
THE POTENTIAL FOR CLOUD COVER TO LINGER INTO THE EARLY EVENING
HOURS. LOWED BY INCREASING CLOUDS AND MODERATION INTO THE
UPPER 40S TO LOWER 50S AHEAD OF THE NEXT SYSTEM FRI. FRONTAL WAVE
DEVELOPMENT IS LIKELY INVOF THE CAROLINA COAST LATE WEEK AS SPLIT
STREAMS ALIGN FAVORABLY FOR STRONG ASCENT CENTERED OFFSHORE THE
CAROLINAS...THOUGH ASSOCIATED SURFACE LOW DEVELOPMENT WILL BE FAST-
MOVING IN THE PROGRESSIVE FLOW. DESPITE LARGER THAN AVG MODEL SPREAD
IN THE MEDIUM RANGE...THERE IS A STRONG ENOUGH SIGNAL IN NWP
GUIDANCE...PARTICULARLY WITH THE WETTER ECMWF SOLUTIONS THAT HAVE
PROVEN MORE ACCURATE PARTICULARLY IN RECENT DAYS...SUCH THAT A SMALL
CHANCE OF PRECIPITATION - AGAIN LIKELY RAIN CHANGING TO SNOW - IS
JUSTIFIED FOR LATE FRI FRI NIGHT. COOLER SAT...THEN MODERATING
SUN...AHEAD OF THE NEXT CLIPPER-TYPE LOW SCHEDULED FOR MON...THOUGH
THIS ONE APPEARS MORE MOISTURE-STARVED AND FARTHER NORTH AS THE
LONGWAVE PATTERN RELAXES BRIEFLY AND THE ZONAL INDEX INCREASES EARLY
NEXT WEEK. ANOTHER ARCTIC AIR MASS WILL BE BUILDING ACROSS CANADA
EARLY TO MID NEXT WEEK...HOWEVER...SO THE NEXT BUCKLE IN THE FLOW
THAT BOTH THE GEFS AND EC ENSEMBLE MEAN DEPICTS WOULD SEND THIS AIR
MASS OUR WAY LATER NEXT WEEK.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 1255 PM TUESDAY...
LIGHT RAIN MOVES OFF TO THE EAST DURING THE REST OF THE AFTERNOON
TAKING THE IFR CONDITIONS WITH IT. SKIES SHOULD CLEAR THIS
EVENING...BUT LOW-LEVEL MOISTURE SHOULD REMAIN...ENOUGH THAT...WITH
LIGHT WINDS OVERNIGHT...EVEN SOMEWHAT ALOFT...AND THE RECENT
RAIN...SOME AREAS OF FOG ARE POSSIBLE. SREF GUIDANCE SUGGESTS THE
HIGHER PROBABILITIES OF FOG SHOULD BE OUTSIDE OF THE TRIAD WHERE THE
SURFACE DEW POINTS SHOULD BE HIGHER OVERNIGHT. AS A RESULT...THE
FORECAST SHOWS CONDITIONS OF MVFR FOG IN THE TRIAD AND IFR FOG
ELSEWHERE LATE TONIGHT. AVIATION INTERESTS SHOULD PREPARE FOR AREAS
OF FOG LATE TONIGHT REGARDLESS OF TRAVEL IN AND AROUND CENTRAL NORTH
CAROLINA. VFR CONDITIONS ARE EXPECTED TO RETURN WEDNESDAY MORNING
AHEAD OF A COLD FRONT MOVING TOWARD THE TRIAD AT THE VERY END OF THE
18Z VALID TAF PERIOD.
BEYOND THE 18Z VALID TAF PERIOD...A COLD FRONT SLOWS OVER CENTRAL
NORTH CAROLINA WEDNESDAY AFTERNOON AND EVENING...THEN PUSHES OFF THE
COAST AS HIGH PRESSURE BUILDS IN BRIEFLY THURSDAY. ANOTHER COLD
FRONT OR TWO MOVES IN FOR THE END OF THE WEEK AND THE WEEKEND. THERE
IS A CHANCE OF LIGHT RAIN LATE WEDNESDAY AFTERNOON TOWARD THE TRIAD
AND THEN ACROSS CENTRAL NORTH CAROLINA WEDNESDAY NIGHT WITH ALSO THE
THREAT OF A PERIOD OF LIGHT SNOW AND MVFR CONDITIONS. THERE IS A
CHANCE OF A SHORT PERIOD OF IFR CONDITIONS THEN. SIMILAR WEATHER IS
POSSIBLE WITH EACH FRONTAL PASSAGE LATE IN THE WEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...SEC/DJF
SHORT TERM...MWS
LONG TERM...MWS
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
329 PM CST TUE JAN 14 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 318 PM CST TUE JAN 14 2014
SKY COVER AND TEMPS THE ISSUE TONIGHT. BAND OF STRATOCU CU OVER
ERN ND ATTM AND HOW/WHEN THIS CLEARS OUT WILL BE THE ISSUE FOR LOW
TEMPS. HRRR AND OTHER SHORT TERM MODELS DO BRING CLEARING TO ERN
ND/RRV THIS EVE AND SPREADS IT EAST. WINDS WILL DIMINISH TOO AND
WITH LIKELY CLEARING/CLEAR SKY FOR A WHILE TEMPS WILL DROP QUICKLY
INTO THE 5 TO 10 BELOW ZERO RANGE MOST AREAS WITH A FEW TEEN BELOW
ZERO TEMPS LIKELY IN PARTS OF FAR NW MN. CLOUDS FROM NEXT SYSTEM
WILL SPREAD INTO WRN FCST AREA AFTER MIDNIGHT AS WINDS TURN SOUTH
AND TEMPS WARM...SO PERIOD OF COLD TEMPS IS SMALL.
STRONG 925-850 MB WARM ADVECTION WILL SPREAD WEST TO EAST OVER THE
AREA WEDNESDAY...WITH BAND OF LIGHT SNOW WITH IT ENDING AS SOME
SLEET/FREEZING RAIN AT THE TAIL END. BUT MODELS DO APPEAR TO BUT
MOST OF THE MOISTURE IN THE COLD AIR TO THE EAST OF THE WARM FRONT
SO THINK ICING WILL BE MINIMAL. THUS NO ADVISORIES ISSUED. BUT
LATER SHIFTS CAN MONITOR.
TEMPS WILL WARM SIGNIFICANTLY WED AFTN OVER ERN ND WITH TEMPS 32F
OR HIGHER AS 925 MB REACH +2C. IT WILL BE TURN WINDY AS WELL ESP
WEST OF THE VALLEY WHERE 45-50 KT 925 MB WINDS WILL BE PRESENT.
HOWEVER WITH WARMER AIR COMING OVER THE COLDER SURFACE AN
INVERSION WILL BE PRESENT AND THUS MIXING WILL BE LIMITED. THUS
DONT ANTICIPATE ANY HEADLINES FOR WIND/BLSN WED AFTN/EVE.
VERY CLOSE THOUGH WED EVE AND WILL NEED TO WATCH WIND POTENTIAL.
ARCTIC FRONT WILL START DROPPING SOUTH INTO THE FAR NRN VALLEY
06Z-09Z AND THEN PLUNGE SOUTH REACHING FAR SRN FCST AREA SOON
AFTER 12Z THU. 925 MB WINDS OF 50 KTS BECOME MORE NORTH-SOUTH AND
WITH STRONG SURAFCE COOLING SOUNDINGS SHOW ADIABATIC CONDITIONS UP
TO AROUND 870 MB. THUS EXPECT THE FRONT TO ARRIVE WITH A STRONG
PUNCH ALONG WITH SOME SNOW SHOWERS. THUS EXPECT A QUICK DOWNTURN
INTO BLIZZARD CONDITIONS JUST AHEAD AND BEHIND FRONT THRU THE LATE
NIGHT WED NIGHT. DID NOT INCLUDE THE FAR EAST (TREES) IN BLIZZARD WATCH.
WHILE SNOWFALL WILL END IN ERN ND/RRV WED NIGHT DO LOOK FOR SOME
LIGHT SNOW TO LINGER OVER LAKE OF THE WOODS REGION..WHERE TOTAL
NEW SNOWFALL OF 1-3 INCHES IS POSSIBLE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 318 PM CST TUE JAN 14 2014
THURSDAY SHOULD SEE BLIZZARD CONDITIONS OVER THE PRAIRIE
REGION....ERN ND/RRV (ROX-FFM WESTWARD). STRONG COLD ADVECTION
STRONG LAPSE RATES WITH GOOD MIXING OF 50 KT 925 MB WINDS TO THE
SFC SHOULD ENSURE BLOWING SNOW AND NEAR ZERO VISIBILITY AT
TIMES...ESP OUT OF TOWN. ANY FALLING SNOWFALL WILL ADD TO THE VSBY
ISSUES. IT WILL BE A FAST MOVING BLIZZARD IN THAT CONDITIONS WILL
IMPROVE LATE IN THE DAY IN THE NORTH AND IN THE EARLY EVENING IN
THE SOUTH.
CONDITIONS MUCH IMPROVED BY 12Z FRI AS SFC HIGH AND CLEARING MOVE
IN WITH LIGHTER WINDS. NEXT WEAK SHORTWAVE WILL MOVE INTO ERN ND
FRI AFTN WITH SOME LIGHT SNOW/FLURRIES.
FOR THE FRIDAY NIGHT TO TUESDAY TIME FRAME THE FA REMAINS IN
NORTHWEST FLOW ALOFT. ONE WEAK SFC LOW PASSES THROUGH THE AREA FRI
NIGHT SO LEFT SOME LIGHT SNOW CHANCES WITH IT. ANOTHER WEAK WAVE AND
ASSOCIATED SFC LOW PASS NORTH OF THE FA SUN NIGHT WHICH COULD RESULT
IN SOME LIGHT SNOW AGAIN MON AND MON NIGHT. NEITHER SYSTEM AT THIS
POINT LOOKS VERY IMPRESSIVE FOR PRODUCING MUCH SNOW. THE UP AND DOWN
TEMP PATTERN LOOKS TO CONTINUE WITH WARMER AIR MOVING BACK IN
ESPECIALLY BY THE WEEKEND FOLLOWED BY COOLER TEMPS FOR EARLY NEXT
WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1240 PM CST TUE JAN 14 2014
THE BAND OF CLOUDS OVER THE AREA RIGHT NOW WILL PROBABLY LINGER INTO
THE MID TO LATE AFTERNOON WITH SOME CLEARING THEN OCCURRING IN ITS
WAKE. SEEING SOME PRETTY BRISK NORTHWEST WINDS WHICH WILL LAST INTO
THE LATE AFTERNOON. THESE WINDS SHOULD BECOME LIGHT BY LATE EVENING
AND THEN SWITCH AROUND TO THE SOUTH BY WED MORNING. WILL ONCE AGAIN
SEE THE WINDS BECOME PRETTY GUSTY BY MID TO LATE WED MORNING WITH
SOME LIGHT SNOW MOVING BACK IN. AT THIS POINT THE LIGHT SNOW LOOKS
TO AFFECT KGFK/KTVF AND KBJI MORE SO THAN KFAR.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...BLIZZARD WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY
EVENING FOR NDZ038-039-049-052-053.
BLIZZARD WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY
AFTERNOON FOR NDZ006>008-014>016-024-026>030-054.
MN...BLIZZARD WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY
EVENING FOR MNZ002-003-022-027-029-030-040.
BLIZZARD WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY
AFTERNOON FOR MNZ001-004-005-007-008-013>015.
&&
$$
SHORT TERM...RIDDLE
LONG TERM...GODON/RIDDLE
AVIATION...RIDDLE