Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/06/12
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
410 AM EST SUN NOV 4 2012
...DENSE FOG TO AFFECT MOST OF THE FORECAST AREA THIS MORNING...
...HIGH RAIN CHANCES LATE MON NIGHT INTO TUESDAY...
.CURRENTLY...WEAK BROAD HIGH PRES IS OVER THE ERN GULF OF MEXICO
PRODUCING A WEAK WLY FLOW OVER THE REGION AND ADVECTION OF MOISTURE
OFF THE GULF OF MEXICO AGAIN LATE TONIGHT. STRONG INVERSION PRESENT
PER HRRR GUIDANCE SOUNDINGS OVER THE AREA AND AS A RESULT ADVECTIVE
FOG EVENT TONIGHT WITH FOG LIKELY TO BE WIDESPREAD INTO THE MID
MORNING HOURS OVER S HALF OF THE FORECAST AREA. A DENSE FOG ADVISORY
HAS BEEN ISSUED FOR NE FL...AND MAY BE EXPANDED IN SE GA LATER THIS
MORNING. TEMPS MOSTLY IN THE 50S...WITH COUPLE OF LOWER 60S READINGS
IN OVER PARTS OF SE GA. FURTHER N...SFC LOW IS OVER ERN TN VALLEY AREA
WITH TRAILING COLD FRONT TO CENTRAL MS AND NRN LA WITH SCT
CONVECTION ALONG THE BOUNDARY OVER WRN AL TO NE LA.
&&
.SHORT TERM...
TODAY...EARLY MORNING FOG AND STRATUS WILL AFFECT A LARGE PERCENTAGE
OF THE FORECAST AREA THROUGH MID MORNING BEFORE BURNING OFF.
SFC FLOW WILL PREVAIL W TO SW TODAY AHEAD OF THE APPROACHING FRONT
FROM THE NW. THE FRONT WILL MOVE INTO SE GA BY LATE AFTN PROVIDING
A FOCUS FOR MAINLY ISOLATED CONVECTION OVER GA AFTER ABOUT 3 PM.
AN ISOLATED STRONG STORM POSSIBLE IN SE GA PER SPC OUTLOOK BUT
OVERALL THREAT LOOKS LIMITED OWING TO RATHER WEAK INSTABILITY. PWATS
REMAINING GENERALLY 1 INCH OR LESS.
TONIGHT...BOTH NAM AND GFS SIMILAR IN TIMING THE FRONT PUSHING SWD
INTO THE FORECAST AREA TO A LINE FROM ABOUT SAINT AUGUSTINE TO
GAINESVILLE BY 12Z MONDAY. RAIN CHANCES GENERALLY 30-40% IN SE GA
AND 20-30% IN NE FL AS THE UPPER SUPPORT REMAINS WEAK AS THE FRONTAL
SYSTEM DIPS SWD. SLIGHT THUNDER CHANCES NEAR THE SE GA COAST AND
COASTAL WATERS. LATE IN THE NIGHT...ADVECTIVE FOG POSSIBLE ONCE
AGAIN OFF THE GULF BUT FURTHER S MAINLY FROM GNV-ST AUGUSTINE SWD.
LOWS IN THE 50S EXPECTED.
MONDAY...THE COLD FRONT IS LIKELY TO MOVE INTO N CENTRAL FL WITH SFC
HIGH PRES MOVING IN FROM THE NE. ONLY SLIGHT RAIN CHANCES DUE TO
LINGERING FRONT NEAR THE AREA OVER THE S ZONES. HIGHS FALL BACK INTO
THE 70S MOST AREAS WITH POSSIBLE NEAR 80 DEG READINGS EXTREME S
ZONES AS THE FRONT PUSHES DOWN THROUGH N AND CENTRAL FL.
MONDAY NIGHT...RAPID CHANGES UNDERWAY AS STRONG POSITIVE TILT
SHORTWAVE TROUGH MOVES IN FROM THE MS VALLEY AND INTO THE SE STATES.
THIS WILL GENERATE BROAD SFC LOW OVER THE NERN GULF ALONG THE
BAROCLINIC ZONE AND IMPRESSIVE Q-VECTOR CONVERGENCE FIELD MOVING
INTO THE OUR CWA BY 12Z TUE. ANTICIPATE POPS INCREASE TO NEAR 50-60%
FROM W TO E BY EARLY MORNING HOURS.
TUESDAY...BOTH GFS AND ECMWF MOVE STRONG 500 MB TROUGH JUST W OF THE
AREA TO THE SE U.S. COAST BY TUE EVENING. SFC LOW PROGGED TO BE IN
THE FL PANHANDLE TUE MORNING WITH WARM FRONT EXTENDING EWD OVER OUR
NE FL AND INTO THE ATLC. SFC LOW EXPECTED TO SHIFT EWD QUICKLY AND
OFF THE COAST BY LATER IN THE DAY...AND TAKE OFF TO THE NE WITH
TRAILING FRONT PUSHING SEWD OF THE AREA IN THE AFTN. CONFIDENCE HAS
RISEN WITH LIKELY POPS OVER THE ENTIRE FCST AREA...AND MAY BE BUMPED
TO CATEGORICAL POPS (AT LEAST 80%) IN LATER FCSTS. WHILE THUNDERSTORM
POTENTIAL REMAINS LIMITED DUE TO WEAK INSTABILITY...STRONG LIFT AND
COLD TEMPS ALOFT AT -18C SUGGEST INCLUDING SLIGHT TSTMS CHANCE OVER
AT LEAST THE SRN 2/3RDS OF THE AREA. TEMPS MAY HOLD STEADY IN THE
60S TO NEAR 70...BUT COULD HOLD IN THE UPPER 50S N ZONES IF CLOUDS
ARE SLOWER TO CLEAR OUT. TUE NIGHT...LOW POPS RESERVED FOR EARLY
EVENING OVER THE ERN ZONES AS WRAP AROUND PRECIP IS POSSIBLE. AS LOW
PRES MOVES NE OF THE AREA HIGH PRES WILL BUILD IN WITH COLDER TEMPS
EXPECTED IN THE 40S. WIND CHILLS IN THE 30S POSSIBLE OVER SE GA.
&&
.LONG TERM...WED-SAT.
DEEP LAYER TROUGH OVER THE ERN U.S. EXPECTED TO SHIFT EWD ALLOWING
STACKED HIGH PRES RIDGE TO MOVE INTO THE ERN U.S. BY EARLY SAT. THE
SFC HIGH LOCATED OVER MS VALLEY WED AND EARLY THU WILL PRODUCE
OCNL BREEZY NW FLOW THEN SFC HIGH PROGGED TO MOVE OFFSHORE BY LATE
FRI THROUGH SAT RESULTING VEERING/WEAK WINDS. TEMPS EXPECTED
TO BE BELOW NORMAL SEVERAL DEGS WED AND THU WITH A MODERATING TREND
BY FRI AND SAT AS UPPER RIDING MOVES INTO THE FORECAST AREA.
WIDESPREAD LOW TEMPS IN THE 40S EXPECTED WED...THU AND FRI MORNINGS.
POPS WILL BE 10% OR LESS DURING THE PERIOD.
&&
.AVIATION...
DENSE FOG BANK FROM THE GULF OF MEXICO WILL CONTINUE TO SPREAD
EAST ACROSS NORTHEAST FLORIDA EARLY THIS MORNING. ONGOING VLIFR
CONDITIONS AT GNV AND VQQ WILL CONTINUE UNTIL ABOUT MID MORNING.
DENSE FOG BANK WILL REACH JAX AND CRG JUST PRIOR TO SUNRISE WITH
POOR CONDITIONS EXPECTED AT THOSE TERMINALS FOR A PERIOD OF
SEVERAL HOURS BEYOND SUNRISE. CONDITIONS WILL IMPROVE MID MORNING
WITH VFR CONDITIONS THEN EXPECTED THROUGH THIS EVENING. ANOTHER
ROUND OF DENSE FOG WILL BE MOST LIKELY AT GNV TONIGHT WITH THE
LATEST DATA SUGGESTING DENSE FOG WILL REMAIN JUST SOUTH OF THE
JACKSONVILLE TERMINALS.
&&
.MARINE...
HIGH PRESSURE WILL SHIFT EAST OF THE AREA TODAY. SOUTHWEST WINDS
WILL INCREASE BY THIS EVENING AS THE GRADIENT TIGHTENS AHEAD OF AN
APPROACHING COLD FRONT. WINDS WILL NEAR CAUTION SPEEDS OFFSHORE
TONIGHT AND A SCEC HEADLINE WILL PROBABLY BE NEEDED. WINDS WILL
VEER TO THE NORTH AND INCREASE TO 15 TO 20 KNOTS BEHIND THE FRONT
ON MONDAY. A SURFACE LOW WILL DEVELOP ALONG THE CENTRAL GULF OF
MEXICO MONDAY NIGHT AND THEN MOVE ACROSS THE NORTHERN FLORIDA
WATERS ON TUESDAY. NORTHERLY WINDS WILL INCREASE TO SCA LEVELS
ACROSS THE SOUTHERN GEORGIA WATERS ON THE NORTH SIDE OF THE LOW
TUESDAY AFTERNOON. THESE CONDITIONS WILL THEN SPREAD SOUTH ACROSS
THE FLORIDA WATERS TUESDAY EVENING AS THE LOW PULLS OFF TO THE
NORTHEAST AND A STRONG COLD FRONT CONTINUES TO SHIFT SOUTH ACROSS
THE AREA.
RIP CURRENTS: LOW RISK TODAY AN INCREASE TO MODERATE RISK BY
TUESDAY DUE TO INCREASING ONSHORE WINDS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 83 52 71 51 / 30 40 10 60
SSI 79 58 70 56 / 20 40 20 60
JAX 83 57 73 55 / 10 20 20 50
SGJ 81 59 74 59 / 10 20 20 40
GNV 82 56 77 54 / 0 20 20 50
OCF 83 57 80 55 / 0 20 20 40
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR ALACHUA-BAKER-
BRADFORD-CLAY-COLUMBIA-DUVAL-FLAGLER-GILCHRIST-HAMILTON-
MARION-NASSAU-PUTNAM-ST JOHNS-SUWANNEE-UNION.
GA...NONE.
AM...NONE.
&&
$$
SHASHY/SHULER/
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
223 PM EST SUN NOV 4 2012
.SHORT TERM /TODAY THROUGH TUESDAY/...
LATEST RAP ANALYSIS OVER THE LOCAL AREA SHOWS SURFACE BASED CAPE
HAS INCREASED TO BETWEEN 500 J/KG AND 750 J/KG OVER THE SOUTHERN
TIER WITH MIXED CAPE VALUES CONSIDERABLY LOWER. BAND OF PRE-
FRONTAL -RA CONTINUES TO MAKE STEADY PROGRESS INTO NORTH CENTRAL
GEORGIA BUT NO CONVECTIVE ELEMENTS OF NOTE WITH THIS ACTIVITY THUS
FAR. INTO THE BETTER INSTABILITY HOWEVER...STARTING TO SEE SOME
MORE ORGANIZED ACTIVITY. HOWEVER...FEEL BY THE TIME STRONG OR
SEVERE COULD BE REALIZED...BEST LIFT WILL HAVE SHIFTED EAST OUT OF
THE AREA THIS EVENING. WILL LIKELY SCALE BACK THE HWO AND ONGOING
GRAPHICAST ONCE DEVELOPING LINE SHIFTS EAST.
MONDAY LOOKS TO BE THE ONLY SHORT TERM DAY WITH FAIRLY BENIGN
CONDITIONS AS HIGH CENTERED OVER CANADA HAS ENOUGH WEAK RIDGING
SOUTH INTO THE OUR AREA TO PRODUCE A POP FREE DAY. CLOUDS HOWEVER
WILL BECOME PLENTIFUL DURING THE DAY HAS MID AND HIGH LEVEL
MOISTURE MAKES A RAPID RETURN TO THE NORTHWEST HALF OF THE REGION.
THESE CLOUDS WILL PLAY AN IMPORTANT ROLE AS THEIR ARRIVAL PRIOR TO
SUNSET WILL RESULT IN MINS TUESDAY MORNING NOT REACHING THEIR FULL
POTENTIAL. THIS WILL BE CRUCIAL AS PRECIP BEGINS TO OVERSPREAD THE
AREA IN EARNEST JUST PRIOR TO DAYBREAK TUESDAY AS CLOSED UPPER LOW
ROTATES THROUGH THE DEEP SOUTH. NAM12 IS BY FAR THE MOST
AGGRESSIVE IN DYNAMICALLY COOLING THE COLUMN...TAKING THE 850MB
TEMP FROM +2C TO -1C IN A MATTER OF TWO HOURS. NOT COMPLETELY OUR
OF THE QUESTION WITH SUCH A DYNAMIC SYSTEM TO SEE THIS TYPE OF
COOLING ALOFT...BUT JUST CANNOT SEEM TO GET SURFACE TEMPS COLD
ENOUGH TO ALLOW ANY FROZEN PRECIP TO REACH THE GROUND. THIS IS TRUE
EVEN IN THE MOUNTAINS AND WILL KEEP FORECAST ALL LIQUID THIS RUN
BUT WILL NEED TO BE MONITORED CLOSELY WITH SUBSEQUENT CYCLES.
AS FAR AS THE THUNDER POTENTIAL...BEST SURFACE INSTABILITY SHOULD
REMAIN SOUTH OF THE AREA...BUT GIVEN THE AMOUNT OF ISENTROPIC
UPGLIDE JUST NORTH OF THE LOW...WILL NEED TO KEEP ISOLATED THUNDER
MENTION FOR THE SOUTHERN TIER.
DEESE
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
GFS AND ECMWF CONTINUE IN ARE IN FAIRLY DECENT AGREEMENT THROUGH
THE EXTENDED...AND FOR THE MOST PART AFTER THE SYSTEM EXITS
TUESDAY NIGHT THE EXTENDED SHOULD BE DRY WITH A GRADUAL WARMING
TREND AS THE MIDLEVEL RIDGE BUILDS IN FROM THE GULF. CORRESPONDING
SURFACE HIGH PRESSURE PUSHES THROUGH THE SOUTHEAST THURSDAY INTO
FRIDAY...ANCHORING ITSELF IN THE WESTERN ATLANTIC BY SATURDAY BUT
WITH STRONG RIDGING REMAINING IN PLACE. HAVE MADE NO SUBSTANTIVE
CHANGES TO THE EXTENDED AT THIS TIME.
TDP
PREV DISCUSSION... /ISSUED 326 AM EST SUN NOV 4 2012/
BIG FORECAST STORY THROUGH THE EXTENDED IS LOW PRESSURE SYSTEM
IMPACTING THE AREA TUESDAY THROUGH WEDNESDAY. MODELS CONTINUE TO
SUGGEST DEEPENING OF THE LOW OVER THE SOUTHERN ALABAMA AND THE FLORIDA
PANHANDLE TUESDAY MORNING THROUGH EARLY AFTERNOON. AS A RESULT OF
THE PROJECTED TRACK...EXPECT BEST RAIN CHANGES TO INITIALLY BE
ACROSS WESTERN GA LATE ON MONDAY INTO EARLY MORNING TUESDAY...THEN
TRANSITIONING TO THE SOUTHERN 2/3 OF THE FORECAST AREA BY TUESDAY
MORNING. PREVIOUS MODEL RUNS HAD SUGGESTED MORE ORGANIZED
DEVELOPMENT TO OUR SOUTH IN THE FORM OF A SQUALL...CUTTING OFF THE
AREA FROM MOISTURE SOURCE...BUT HAVE OPTED TO INCREASE POPS CONSIDERABLY
DUE TO THE AGREEMENT WITH THE LATEST MODEL RUNS OF THE NORTHERN
MOISTURE PROGRESSION. LITTLE OVERALL INSTABILITY WITH THIS SYSTEM
HAS LIMITED THE MENTION OF THUNDER IN THE FORECAST...THOUGH DID
KEEP MENTION OF ISOLATED CONVECTION IN THE FAR SE CWA TUESDAY LATE
MORNING THROUGH EARLY AFTERNOON.
CENTER OF THE SURFACE LOW TRACKS ACROSS NORTHERN FLORIDA INTO
TUESDAY NIGHT...AND EMERGES OFF THE GEORGIA AND CAROLINA COASTS BY
WEDNESDAY MORNING. HIGH PRESSURE BUILDS IN BEHIND THE
LOW AND ASSOCIATED FRONT...KEEPING THE REMAINDER OF THE LONG TERM
FORECAST DRY. COOLER TEMPERATURES IN THE MIDDLE OF THE WEEK WILL
GRADUALLY WARM BY THE WEEKEND.
31
&&
AVIATION...
18Z UPDATE...
BAND OF INTERMITTENT -RA AHEAD OF A COLD FRONT IS CURRENTLY
PUSHING THROUGH THE ATL AREA TERMINALS. NO REDUCTIONS TO VSBY OR
CIG NOTED WITH THIS ACTIVITY BUT HAVE NOTED SOME CIG REDUCTIONS TO
MVFR IN ITS WAKE. WILL CARRY -RA FOR ATL FOR THE NEXT COUPLE OF
HOURS FOLLOWED WITH A TEMPO FOR BKN025. FURTHER SOUTH OVER MCN AND
CSG...PROSPECTS FOR TSRA APPEAR TO BE WANING BUT DEVELOPMENT JUST
SOUTH OF THE AREA WARRANTS KEEPING VCTS FOR NOW.
//ATL CONFIDENCE...18Z UPDATE...
MEDIUM ON CIG AND WIND SHIFT MONDAY.
HIGH ON REMAINING ELEMENTS.
DEESE
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 74 44 62 42 / 30 5 0 50
ATLANTA 73 43 64 46 / 30 0 0 60
BLAIRSVILLE 63 37 57 40 / 20 0 0 50
CARTERSVILLE 68 38 63 41 / 20 0 0 60
COLUMBUS 79 44 69 48 / 30 20 0 80
GAINESVILLE 69 45 60 44 / 20 0 0 50
MACON 83 43 68 44 / 30 30 0 80
ROME 67 36 64 40 / 20 0 0 60
PEACHTREE CITY 73 37 65 40 / 40 0 0 70
VIDALIA 86 54 68 49 / 30 40 0 70
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...DEESE
LONG TERM....TDP
AVIATION...DEESE
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
744 AM CST SUN NOV 4 2012
.UPDATE...
LATEST RAP TRENDS INDICATES THE PRECIP OVER THE NORTHEAST HALF OF
THE CWFA WILL RAPIDLY DISSIPATE OVER THE NEXT COUPLE OF HOURS DUE
TO A LACK OF CONVERGENCE. ACROSS THE SOUTHEAST HALF OF THE CWFA
CONVERGENCE IS PROGGED TO INCREASE EVEN AS THE OVERALL FORCING
DECREASES. THUS PRECIPITATION WILL LINGER LONGER ACROSS ROUGHLY
THE SOUTH HALF THAN THE NORTH HALF THE REMAINDER OF THE MORNING.
THE ENDING OF PRECIPITATION SHOULD ALLOW TEMPERATURES TO SLOWLY
RISE. SOME BREAKS MAY DEVELOP IN THE CLOUDS LATER TODAY AS
SUBSIDENCE DEVELOPS BEHIND THE DEPARTING SHORTWAVE. ..08..
&&
.PREV DISCUSSION... /ISSUED 555 AM CST SUN NOV 4 2012/
UPDATE...
TRENDS FROM THE 06Z WRF AND THE RAP MODEL WITH INPUT FROM AREA
RADARS INDICATE AN ADJUSTMENT SOUTHWARD IS NEEDED FOR THE CURRENT
POPS THIS MORNING. BOTH THE WRF AND RAP MODELS INDICATE THE
OVERALL FORCING WILL BEGIN TO RAPIDLY WEAKEN AFTER 12Z. THE
PRECIPITATION SO FAR HAS BEEN VERY SPOTTY AND WITH THE FORCING
PROGGED TO GET WEAKER THE AREAL COVERAGE WILL DECREASE OVER THE
NEXT SEVERAL HOURS.
SUBSIDENCE BEHIND THE SHORTWAVE MAY ALLOW THE CLOUDS TO BREAK UP
AROUND MID DAY AND INTO THE AFTERNOON. HOWEVER...THE DENSE CI/CS
SHIELD FROM THE NEXT SYSTEM SHOULD ALSO BE ARRIVING AT THAT TIME.
AT THE VERY BEST SOME EXTREMELY FILTERED SUN MAY BE POSSIBLE. A
MORE LIKELY SCENARIO IS CONTINUED CLOUD COVER. IF THE LATTER
SCENARIO OCCURS IT WOULD HAVE A NEGATIVE IMPACT ON TEMPERATURES.
BASED ON AN APPROXIMATED ARRIVAL OF MID DAY FOR THE CLOUD SHIELD
OF THE NEXT SYSTEM...MAX TEMPERATURES WERE LOWERED A FEW DEGREES
TO GIVE HIGHS IN THE 45 TO 50 DEGREE RANGE. ..08..
AVIATION...
MAINLY VFR WX WILL BE SEEN THROUGH 12Z/05 AS A WEAK UPPER LEVEL
DISTURBANCE MOVES THROUGH THE AREA. THERE MAY BE SOME SPRINKLES OR
-SHRA AT KCID/KDBQ/KMLI AS THE DISTURBANCE PASSES THROUGH. THERE
MAY OR MAY NOT BE SOME MVFR VSBYS AT KBRL AROUND SUNRISE. AFT
06Z/05 YET ANOTHER UPPER LEVEL DISTURBANCE WILL MOVE THROUGH IOWA
BUT ALL TAF SITES SHOULD REMAIN VFR. ..08..
PREV DISCUSSION... /ISSUED 303 AM CST SUN NOV 4 2012/
SYNOPSIS...
06Z SFC ANALYSIS HAS A VERY WEAK LOW NEAR KORC. TROFS EMANATED FROM
THE LOW INTO SOUTHWEST MINNESOTA...INTO SOUTHERN IOWA...AND BACK
WEST INTO NEBRASKA. DEW POINTS AROUND THE LOW AND TROFS WERE IN THE
30S WHILE 20S WERE IN THE GREAT LAKES REGION. DEW POINTS IN THE 40S
AND 50S WERE ACROSS THE TENNESSEE VALLEY AND DEEP SOUTH.
SATELLITE/RADAR TRENDS SHOW CLOUDS ASSOCIATED WITH THE UPPER LEVEL
WAVE MOVING INTO THE AREA WITH PLENTY OF VIRGA ON RADAR. HOWEVER...
PRECIPITATION WAS REACHING THE GROUND AND WAS MEASURABLE IN SPOTS.
SHORT TERM...TODAY AND TONIGHT...
THE CURRENT WAVE MOVING INTO THE AREA IS BEST DEPICTED USING THE
290K THETA SFC CONDENSATION PRESSURE DEFICITS/FORCING FROM THE WRF.
THE TREND WITH THE OVERALL FORCING IS TO RAPIDLY WEAKEN PRIOR TO
SUNRISE AND DURING THE MORNING HOURS AS THE SYSTEM ENCOUNTERS DRIER
AIR OVER THE AREA. USING THE ABOVE APPROACH IN CONCERT WITH IMPLIED
FORCING FROM THE TRACK OF THE VORT MAX SUGGESTS THE NORTHERN HALF
SHOULD SEE SPRINKLES WITH SOME VERY LIGHT RAIN IN THE PRE-DAWN HOURS
WITH THE AREAL COVERAGE SHRINKING AFTER SUNRISE AS THE FORCING
COLLAPSES.
THERE IS A CONCERN...WHICH THE WRF 290K THETA SFC SHOWED...THAT
SPRINKLES OR VERY LIGHT RAIN MAY DEVELOP ACROSS THE SOUTHERN HALF OF
THE CWFA PRIOR TO SUNRISE ON THE LEADING EDGE OF THE WEAKENING
FORCING. CURRENTLY RADAR SHOWS ECHOES INCREASING AND MOVING INTO THE
SOUTHERN HALF OF THE CWFA. THESE ECHOES ARE LIKELY A COMBINATION OF
CLOUDS/VIRGA BUT NO SFC STATION IS REPORTING PRECIPITATION. THIS
SITUATION WILL NEED TO BE MONITORED CLOSELY FOR POTENTIAL
PRECIPITATION THROUGH SUNRISE AND INTO THE MORNING.
BASED ON THE TRENDS IN FORCING...THE AFTERNOON HOURS LOOK TO BE DRY
ACROSS THE AREA AS SUBSIDENCE MOVES IN BEHIND THE SHORT WAVE. THERE
SHOULD BE SOME PARTIAL CLEARING THAT DEVELOPS DURING THE AFTERNOON
WHICH WOULD ALLOW TEMPERATURES TO BE SIMILAR TO YESTERDAY. IF CLOUDS
HOLD INTO THE AFTERNOON THEN THE CURRENT UPPER 40S/LOWER 50S FOR
HIGHS WILL BE TOO WARM.
QUIET AND DRY CONDITIONS SHOULD BE SEEN DURING THE EARLY EVENING
WHILE THE NEXT...MORE SUBSTANTIAL...SHORTWAVE DROPS SOUTHEAST FROM
THE NORTHERN PLAINS. THE OVERALL FORCING AND LOWERING OF
CONDENSATION PRESSURE DEFICITS SUGGEST SPRINKLES/VERY LIGHT RAIN
SHOULD BEGIN MOVING INTO THE FAR SOUTHWEST/WEST DURING THE LATE
EVENING HOURS. AFTER MIDNIGHT THE FORCING INCREASES AND ROUGHLY THE
SOUTHWEST THIRD TO WESTERN HALF OF THE CWFA SHOULD SEE
SPRINKLES/LIGHT RAIN. THE FAR SOUTHWEST PART OF THE CWFA APPEARS TO
HAVE THE BEST CHANCE OF SEEING MEASURABLE RAIN. 08
LONG TERM...MONDAY THROUGH NEXT SATURDAY...
CLIPPER SYSTEM TO SHIFT SOUTH OF REGION ON MON WITH RAIN MAINLY WEST
OF KIIB-KGBG LINE TAPERING OFF BY MIDDAY. CLOUDS REMAIN IN WAKE BUT
LIKELY TO SEE SOME BREAKS IN AFTERNOON WITH SUBSIDENCE. SIDED TOWARD
COOL SIDE OF GUIDANCE FOR HIGHS ACROSS THE SOUTH/WEST CWA WHERE
LIKELY TO SEE MORE CLOUDINESS LINGER WHILE OPTED FOR BLEND ELSEWHERE
WITH POTENTIAL FOR MORE PEAKS OF SUNSHINE.
NEXT IN SERIES OF CLIPPER SYSTEMS PROGGED TO DIVE DOWN THROUGH THE
GREAT LAKES TUE-TUE NGT. DIFFLUENT FLOW ALOFT... DECENT ELEVATED
MOISTURE ADVECTION AND LIFT ATTENDANT TO LEFT EXIT REGION OF
110-120 KT H3 JET SUPPORT BAND OF PCPN SWEEPING ACROSS CWA TUE AM
EXITING DURING THE AFTN. HAVE RAISED POPS ALL AREAS WITH LIKELY POPS
NORTHEAST HALF OF CWA... BUT IF FORCING SIGNAL REMAINS THEN WOULD
NEED TO RAISE POPS FURTHER TO LIKELY TO CATEGORICAL OVER GOOD PORTION
OF CWA FOR MAINLY FIRST HALF OF DAY TUE. LIMITED MOISTURE AND SPEED
OF SYSTEM TO KEEP PCPN AMOUNTS LIGHT AND GENERALLY FROM A FEW
HUNDREDTHS TO AROUND 0.1 INCH. HIGHS TUE REMAIN BELOW NORMAL IN THE
40S TO L50S WITH THE COOLEST READINGS LIKELY TO BE IN THE N/E CWA.
WED-FRI... MAINLY DRY WITH WARMING TREND ESPECIALLY THU-FRI WHEN
TEMPS EXPECTED TO BE AT OR ABOVE NORMAL... AS UPPER LEVEL RIDGING
BUILDS INTO THE REGION.
NEXT WEEKEND CONTINUES TO LOOK INCREASINGLY UNSETTLED/WET WITH
POTENTIAL FOR PERIOD OF MODERATE TO LOCALLY HEAVY RAINS... AS
UPPER LEVEL ENERGY EJECTS FROM THE SOUTHWEST CONUS AND INTERACTS
WITH GULF MOISTURE. TEMPS TO START OUT THE WEEKEND ABOVE NORMAL BUT
LIKELY TO RETURN NEAR TO BELOW NORMAL BY EARLY NEXT WEEK WITH PASSAGE
OF COLD FRONT. 05
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
555 AM CST SUN NOV 4 2012
.UPDATE...
TRENDS FROM THE 06Z WRF AND THE RAP MODEL WITH INPUT FROM AREA
RADARS INDICATE AN ADJUSTMENT SOUTHWARD IS NEEDED FOR THE CURRENT
POPS THIS MORNING. BOTH THE WRF AND RAP MODELS INDICATE THE
OVERALL FORCING WILL BEGIN TO RAPIDLY WEAKEN AFTER 12Z. THE
PRECIPITATION SO FAR HAS BEEN VERY SPOTTY AND WITH THE FORCING
PROGGED TO GET WEAKER THE AREAL COVERAGE WILL DECREASE OVER THE
NEXT SEVERAL HOURS.
SUBSIDENCE BEHIND THE SHORTWAVE MAY ALLOW THE CLOUDS TO BREAK UP
AROUND MID DAY AND INTO THE AFTERNOON. HOWEVER...THE DENSE CI/CS
SHIELD FROM THE NEXT SYSTEM SHOULD ALSO BE ARRIVING AT THAT TIME.
AT THE VERY BEST SOME EXTREMELY FILTERED SUN MAY BE POSSIBLE. A
MORE LIKELY SCENARIO IS CONTINUED CLOUD COVER. IF THE LATTER
SCENARIO OCCURS IT WOULD HAVE A NEGATIVE IMPACT ON TEMPERATURES.
BASED ON AN APPROXIMATED ARRIVAL OF MID DAY FOR THE CLOUD SHIELD
OF THE NEXT SYSTEM...MAX TEMPERATURES WERE LOWERED A FEW DEGREES
TO GIVE HIGHS IN THE 45 TO 50 DEGREE RANGE. ..08..
&&
.AVIATION...
MAINLY VFR WX WILL BE SEEN THROUGH 12Z/05 AS A WEAK UPPER LEVEL
DISTURBANCE MOVES THROUGH THE AREA. THERE MAY BE SOME SPRINKLES OR
-SHRA AT KCID/KDBQ/KMLI AS THE DISTURBANCE PASSES THROUGH. THERE
MAY OR MAY NOT BE SOME MVFR VSBYS AT KBRL AROUND SUNRISE. AFT
06Z/05 YET ANOTHER UPPER LEVEL DISTURBANCE WILL MOVE THROUGH IOWA
BUT ALL TAF SITES SHOULD REMAIN VFR. ..08..
&&
.PREV DISCUSSION... /ISSUED 303 AM CST SUN NOV 4 2012/
SYNOPSIS...
06Z SFC ANALYSIS HAS A VERY WEAK LOW NEAR KORC. TROFS EMANATED FROM
THE LOW INTO SOUTHWEST MINNESOTA...INTO SOUTHERN IOWA...AND BACK
WEST INTO NEBRASKA. DEW POINTS AROUND THE LOW AND TROFS WERE IN THE
30S WHILE 20S WERE IN THE GREAT LAKES REGION. DEW POINTS IN THE 40S
AND 50S WERE ACROSS THE TENNESSEE VALLEY AND DEEP SOUTH.
SATELLITE/RADAR TRENDS SHOW CLOUDS ASSOCIATED WITH THE UPPER LEVEL
WAVE MOVING INTO THE AREA WITH PLENTY OF VIRGA ON RADAR. HOWEVER...
PRECIPITATION WAS REACHING THE GROUND AND WAS MEASURABLE IN SPOTS.
SHORT TERM...TODAY AND TONIGHT...
THE CURRENT WAVE MOVING INTO THE AREA IS BEST DEPICTED USING THE
290K THETA SFC CONDENSATION PRESSURE DEFICITS/FORCING FROM THE WRF.
THE TREND WITH THE OVERALL FORCING IS TO RAPIDLY WEAKEN PRIOR TO
SUNRISE AND DURING THE MORNING HOURS AS THE SYSTEM ENCOUNTERS DRIER
AIR OVER THE AREA. USING THE ABOVE APPROACH IN CONCERT WITH IMPLIED
FORCING FROM THE TRACK OF THE VORT MAX SUGGESTS THE NORTHERN HALF
SHOULD SEE SPRINKLES WITH SOME VERY LIGHT RAIN IN THE PRE-DAWN HOURS
WITH THE AREAL COVERAGE SHRINKING AFTER SUNRISE AS THE FORCING
COLLAPSES.
THERE IS A CONCERN...WHICH THE WRF 290K THETA SFC SHOWED...THAT
SPRINKLES OR VERY LIGHT RAIN MAY DEVELOP ACROSS THE SOUTHERN HALF OF
THE CWFA PRIOR TO SUNRISE ON THE LEADING EDGE OF THE WEAKENING
FORCING. CURRENTLY RADAR SHOWS ECHOES INCREASING AND MOVING INTO THE
SOUTHERN HALF OF THE CWFA. THESE ECHOES ARE LIKELY A COMBINATION OF
CLOUDS/VIRGA BUT NO SFC STATION IS REPORTING PRECIPITATION. THIS
SITUATION WILL NEED TO BE MONITORED CLOSELY FOR POTENTIAL
PRECIPITATION THROUGH SUNRISE AND INTO THE MORNING.
BASED ON THE TRENDS IN FORCING...THE AFTERNOON HOURS LOOK TO BE DRY
ACROSS THE AREA AS SUBSIDENCE MOVES IN BEHIND THE SHORT WAVE. THERE
SHOULD BE SOME PARTIAL CLEARING THAT DEVELOPS DURING THE AFTERNOON
WHICH WOULD ALLOW TEMPERATURES TO BE SIMILAR TO YESTERDAY. IF CLOUDS
HOLD INTO THE AFTERNOON THEN THE CURRENT UPPER 40S/LOWER 50S FOR
HIGHS WILL BE TOO WARM.
QUIET AND DRY CONDITIONS SHOULD BE SEEN DURING THE EARLY EVENING
WHILE THE NEXT...MORE SUBSTANTIAL...SHORTWAVE DROPS SOUTHEAST FROM
THE NORTHERN PLAINS. THE OVERALL FORCING AND LOWERING OF
CONDENSATION PRESSURE DEFICITS SUGGEST SPRINKLES/VERY LIGHT RAIN
SHOULD BEGIN MOVING INTO THE FAR SOUTHWEST/WEST DURING THE LATE
EVENING HOURS. AFTER MIDNIGHT THE FORCING INCREASES AND ROUGHLY THE
SOUTHWEST THIRD TO WESTERN HALF OF THE CWFA SHOULD SEE
SPRINKLES/LIGHT RAIN. THE FAR SOUTHWEST PART OF THE CWFA APPEARS TO
HAVE THE BEST CHANCE OF SEEING MEASURABLE RAIN. 08
LONG TERM...MONDAY THROUGH NEXT SATURDAY...
CLIPPER SYSTEM TO SHIFT SOUTH OF REGION ON MON WITH RAIN MAINLY WEST
OF KIIB-KGBG LINE TAPERING OFF BY MIDDAY. CLOUDS REMAIN IN WAKE BUT
LIKELY TO SEE SOME BREAKS IN AFTERNOON WITH SUBSIDENCE. SIDED TOWARD
COOL SIDE OF GUIDANCE FOR HIGHS ACROSS THE SOUTH/WEST CWA WHERE
LIKELY TO SEE MORE CLOUDINESS LINGER WHILE OPTED FOR BLEND ELSEWHERE
WITH POTENTIAL FOR MORE PEAKS OF SUNSHINE.
NEXT IN SERIES OF CLIPPER SYSTEMS PROGGED TO DIVE DOWN THROUGH THE
GREAT LAKES TUE-TUE NGT. DIFFLUENT FLOW ALOFT... DECENT ELEVATED
MOISTURE ADVECTION AND LIFT ATTENDANT TO LEFT EXIT REGION OF
110-120 KT H3 JET SUPPORT BAND OF PCPN SWEEPING ACROSS CWA TUE AM
EXITING DURING THE AFTN. HAVE RAISED POPS ALL AREAS WITH LIKELY POPS
NORTHEAST HALF OF CWA... BUT IF FORCING SIGNAL REMAINS THEN WOULD
NEED TO RAISE POPS FURTHER TO LIKELY TO CATEGORICAL OVER GOOD PORTION
OF CWA FOR MAINLY FIRST HALF OF DAY TUE. LIMITED MOISTURE AND SPEED
OF SYSTEM TO KEEP PCPN AMOUNTS LIGHT AND GENERALLY FROM A FEW
HUNDREDTHS TO AROUND 0.1 INCH. HIGHS TUE REMAIN BELOW NORMAL IN THE
40S TO L50S WITH THE COOLEST READINGS LIKELY TO BE IN THE N/E CWA.
WED-FRI... MAINLY DRY WITH WARMING TREND ESPECIALLY THU-FRI WHEN
TEMPS EXPECTED TO BE AT OR ABOVE NORMAL... AS UPPER LEVEL RIDGING
BUILDS INTO THE REGION.
NEXT WEEKEND CONTINUES TO LOOK INCREASINGLY UNSETTLED/WET WITH
POTENTIAL FOR PERIOD OF MODERATE TO LOCALLY HEAVY RAINS... AS
UPPER LEVEL ENERGY EJECTS FROM THE SOUTHWEST CONUS AND INTERACTS
WITH GULF MOISTURE. TEMPS TO START OUT THE WEEKEND ABOVE NORMAL BUT
LIKELY TO RETURN NEAR TO BELOW NORMAL BY EARLY NEXT WEEK WITH PASSAGE
OF COLD FRONT. 05
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
451 PM MST MON NOV 5 2012
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 112 PM MST MON NOV 5 2012
LATEST WATER VAPOR AND RUC ANALYSIS DEPICT AN UPPER LEVEL RIDGE OVER
THE WEST COAST...A SHORT WAVE TROUGH OVER SOUTHWEST CANADA WITH HIGH
CLOUDS AHEAD OF IT OVER MONTANA SOUTH INTO COLORADO AND KANSAS.
ANOTHER SHORT WAVE TROUGH WAS LOCATED OVER EASTERN OKLAHOMA AND
CONTINUES TO DEEPEN. AT THE SURFACE A WARM FRONT WAS IN PLACE
ALONG THE KS/CO BORDER NORTH INTO FAR SOUTHWEST SOUTH DAKOTA
THANKS TO THE DOWNSLOPE WINDS COMING OFF THE ROCKIES.
TONIGHT A SHORT WAVE RIDGE IN BETWEEN THE TROUGH OVER CANADA AND THE
ONE TO OUR SOUTHEAST WILL MOVE OVER THE AREA. AT THE SURFACE A
TROUGH WILL MOVE IN AHEAD OF THE UPPER LEVEL RIDGE. WINDS WILL
SHIFT WEST WITH THE TROUGH PASSAGE THEN TURN BACK NORTH BEHIND
IT. WITH A DRY ENVIRONMENT IN PLACE THE TROUGH PASSAGE WILL BE
DRY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 256 PM MST MON NOV 5 2012
FORECAST CONCERNS WILL BE THE AMOUNT OF WARMUP/FIRE WEATHER CONCERNS
WEDNESDAY THROUGH FRIDAY FOLLOWED BY COLDER TEMPERATURES/CHANCE OF
PRECIPITATION NEXT WEEKEND. SATELLITE SHOWING AN AMPLIFIED/AMPLIFYING
AND ACTIVE FLOW FROM THE PACIFIC INTO THE WESTERN ATLANTIC. SYSTEMS
TO NOTE...DEEPENING SOON TO BE STRONG SYSTEM DIGGING INTO THE
EASTERN PORTION OF THE COUNTRY WITH VERY STRONG SYSTEM
MOVING/DEVELOPING IN SOUTHERN CANADA AT THIS TIME. DRY AIR MASS
CURRENTLY RESIDES OVER THE AREA.
AT JET LEVEL...THE NAM FOLLOWED BY THE GFS WAS DOING THE BEST ON THE
VERY STRONG THAT RUNS FROM THE GULF OF ALASKA AND ON THE WEST SIDE
OF DEVELOPING EASTERN CONUS SYSTEM. AT MID LEVELS...THE GFS WAS DOING
A LITTLE BETTER THAN EVERYTHING ELSE. THE SREF AND NAM WERE DOING
BEST ON THE SURFACE WIND AND PRESSURE FIELD. THE NAM...GFS AND
CANADIAN WERE DOING BEST AT THIS TIME ON THE LOW LEVEL THERMAL
FIELD.
TUESDAY NIGHT...LITTLE CLOUD COVER AND LIGHT WINDS...ESPECIALLY IN
THE EAST...WILL ALLOW TEMPERATURES TO FALL BELOW GUIDANCE. MINS
RECENTLY HAVE FALLING WELL BELOW NWP. WENT IN THAT DIRECTION AND
CLOSER TO THE GEM 2 METER TEMPERATURES.
WEDNESDAY/WEDNESDAY NIGHT...DURING THE DAY THE SURFACE RIDGE PULLS
AWAY WITH A CHILLY START...ESPECIALLY IN THE EAST. NEWER NAM IS LESS
AGGRESSIVE WITH THE DOWNSLOPE COMPONENT. HOWEVER...WILL HAVE PLENTY
OF SUN AND WESTERLY FLOW ALOFT. KEPT TEMPERATURES ABOUT THE SAME
EXCEPT WARMING THEM UP A TOUCH. THE WIND FIELD LOOKS TO BE A LITTLE
LIGHT...ESPECIALLY IN THE EAST. AS TROUGH LINE PASSES THROUGH THE
TEMPERATURES WILL DROP WITH THEM WARMING UP AS DOWNSLOPE WINDS
INCREASE BEHIND THE TROUGH. SO WILL BE A LITTLE TRICKY.
THURSDAY...MODELS ALL OVER THE PLACE ON BOUNDARY PLACEMENT AND
TIMING AND RESULTING LOW LEVEL TEMPERATURES. CONSIDERING THE
EXPECTED FLOW ALOFT...THE MODELS MAY BE RUSHING THINGS A LITTLE BIT.
AT THIS TIME...DID A COMPROMISE BETWEEN THE WARMEST AND COOLEST
TEMPERATURES BUT DEFINITELY COULD SEE IT BEING WARMER.
THURSDAY NIGHT THROUGH MONDAY...MAJOR FEATURE OF INTEREST IS HOW
THE DEVELOPING WESTERN TROUGH WILL AFFECT THE WEATHER. THE MODELS
AND ENSEMBLES HAVE THE SAME GENERAL IDEA OF AN ELONGATED TROUGH WITH
THE STRONGEST/BEST DYNAMICS MUCH FURTHER NORTH AND SPLITTING OFF
THE WEAKER SOUTHERN END FURTHER SOUTH LEAVING OUR AREA IN THE
MIDDLE. MODELS DO DIFFER ON THE SPEED OF THE TROUGH WITH MORE
SUPPORT FOR A SLOWER ARRIVAL.
TEMPERATURES THURSDAY NIGHT WILL BE RATHER TRICKY. COLD FRONT THAT
IS EXPECTED TO MOVE THROUGH SOMETIME ON THURSDAY IS EXPECTED TO
RETURN NORTH AS A WARM FRONT THURSDAY NIGHT INTO FRIDAY. MODEL IN
GENERAL AGREEMENT ON FRIDAY WITH THE FRONT NEAR OR NORTH OF THE
FORECAST AREA BY LATE IN THE DAY. OVER THE SOUTHERN HALF TO TWO
THIRDS...MODELS AGREE ON VERY WARM 850 MB TEMPERATURES. WILL HAVE
DEEP SOUTHWEST FLOW ALOFT. AT THIS TIME DO NOT EXPECT THICK CLOUD
COVER. AS A RESULT OF THAT AND COLLABORATION...WARMED UP MAXES.
THIS WARM UP STILL MAY NOT BE ENOUGH.
FRIDAY NIGHT INTO SATURDAY THE FRONT COMES BACK SOUTH AS A COLD
FRONT. SOME DISCREPANCY ON TIMING BUT THERE LOOKS TO BE A THICKENING
CLOUD DECK AND DEVELOPING PRECIPITATION THROUGH THE DAY. SO LEFT
THE INHERITED INIT ALONE. VERY COLD TEMPERATURES FOLLOWING
ESPECIALLY FOR SATURDAY NIGHT INTO SUNDAY NIGHT. INIT GRIDS LOOK
FINE BUT DID MAKE A MINOR ADJUSTMENT DOWN.
SATURDAY...ESPECIALLY FROM THE AFTERNOON...INTO SUNDAY LOOKS TO BE
OUR CHANCE FOR PRECIPITATION. ONLY CONCERN NOW IS IF THE SLOWER
SOLUTIONS PREVAIL...THE PRECIPITATION COULD START LATER IN THE DAY
ON SATURDAY AND CONTINUE THROUGH MORE OF SUNDAY. DESPITE THE BRUNT
OF THE LIFT BEING FURTHER NORTH...RIGHT REAR QUADRANT OF JET...VERY
STRONG PV ANOMALY...AND STRONG CO-LOCATED MESOSCALE FORCING LOCATED
WITH FAVORABLE THETA-E LAPSE RATES...DO SUPPORT LIGHT PRECIPITATION
OCCURRING. THINK WE WILL GET SOMETHING JUST NOT SURE HOW MUCH. AM
CONCERNED AND WILL HAVE TO BE WATCHED CAREFULLY IN UPCOMING
FORECASTS OF BANDED PRECIPITATION DEVELOPING OVER THE AREA. KEPT
THE PHASE RAIN SATURDAY AFTERNOON AND SWITCHED IT OVER TO ALL SNOW
SATURDAY NIGHT. DEPENDING ON HOW LONG THE PRECIPITATION LINGERS
INTO SUNDAY...COULD BE ALL SNOW OR A RAIN AND SNOW MIXTURE. FOR THE
PRECIPITATION KEPT WHAT THE INIT GRID PRODUCED. REMAINDER OF THE
FORECAST IS DRY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 446 PM MST MON NOV 5 2012
A SURFACE TROUGH WILL MOVE PAST KGLD AND KMCK LATE TONIGHT CAUSING
WINDS TO SHIFT TO THE NORTHWEST. VFR CONDITIONS WILL PREVAIL
THROUGH THE NEXT 24 HOURS WITH BROKEN TO SCATTERED HIGH LEVEL CLOUDS.
&&
.FIRE WEATHER...
ISSUED AT 256 PM MST MON NOV 5 2012
ON WEDNESDAY...RELATIVE HUMIDITIES WILL BECOME LOW. HOWEVER THE WIND
FIELD LOOKS TO BE TOO LIGHT SO DO NOT EXPECT ANY FIRE WEATHER
HIGHLIGHTS.
ON FRIDAY...THIS DAY WILL HAVE TO BE WATCHED CAREFULLY. RELATIVE
HUMIDITIES BE SOUTH OF THE WARM FRONT. WINDS WILL ALSO PICK UP IN
THE SAME AREA. IF WARM FRONT IS FASTER MOVING NORTH AND THE WINDS
END UP STRONGER...THERE MAY BE A NEED FOR A FIRE WEATHER HIGHLIGHT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...JTL
LONG TERM...BULLER
AVIATION...FS
FIRE WEATHER...BULLER
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1232 PM EST SUN NOV 4 2012
.UPDATE...
ISSUED AT 1138 AM EST SUN NOV 4 2012
BASED OFF LATEST RADAR TRENDS AND HIGH RESOLUTION MODEL
GUIDANCE...HAVE BUMPED UP THE ISOLATED FLURRIES TO ISOLATED SNOW
SHOWERS /MIXED WITH RAIN THIS AFTERNOON NEAR THE LAKESHORE/. EXPECT
A SIMILAR SITUATION TO OCCUR THIS AFTERNOON AS YESTERDAY
AFTERNOON...WHERE DIURNAL AFFECTS WERE ABLE TO LIFT THE INVERSION A
FEW HUNDRED FEET AND ENOUGH TO ENABLE ISOLATED SHOWERS WITH THE LAKE
SUPERIOR SFC-H925 DELTA-T OF 13. HAVE CONTINUED THIS OVER THE NORTH
CENTRAL AND KEWEENAW THROUGH THE NIGHT AND INTO TOMORROW
MORNING...LARGELY FOLLOWING THE SLOWLY VEERING LIGHT FLOW FROM NORTH
TO EAST THROUGH TOMORROW AFTERNOON.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 443 AM EST SUN NOV 4 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A LONGWAVE PATTERN WITH A
MID/UPPER LEVEL RIDGE INTO THE WRN CONUS AND A TROUGH OVER THE EAST.
A SHRTWV TROUGH WAS LOCATED OVER NE IA WHILE A RIDGE EXTENDED FROM
NORTH DAKOTA INTO NE MANITOBA LEAVING WEAK NRLY FLOW THROUGH THE NRN
GREAT LAKES. AT THE SFC...HIGH PRES EXTENDED FROM NRN MANITOBA AND
NW ONTARIO THROUGH WRN LAKE SUPERIOR INTO WI RESULTING IN ACYC NRLY
FLOW ACROSS LAKE SUPERIOR AND UPPER MI. SHALLOW MOISTURE TRAPPED
BELOW A 2K-3K FT INVERSION WITH 925 MB TEMPS TO AROUND -6C HAS
PROVIDED ENOUGH INSTABILITY TO SUPPORT ISOLATED LAKE EFFECT FLURRIES
INTO N CNTRL UPPER MI. OTHERWISE...IR LOOP SHOWED LOW CLOUDS ACROSS
NRN ONTARIO THROUGH THE CWA.
SATELLITE TRENDS AND MODELS 925 RH SUGGEST THAT...SIMILAR TO
YESTERDAY...THE LOW CLOUDS WILL PERSIST OVER THE AREA GIVEN LITTLE
CHANGE IN THE TEMP PROFILE AND ONLY A GRADUAL WIND SHIFT. THERE MAY
BE SOME AFTERNOON CLEARING AGAIN OVER THE SOUTHWEST...WHERE MIXING
MAY HELP PUSH THE EDGE OF THE CLOUDS BACK TO THE NORTHEAST. EVEN
THOUGH INSTABILITY AND THE WIND FIELDS REMAIN WEAK...SOME
ISOLATED/INTERMITTENT FLURRIES WILL REMAIN POSSIBLE OVER N CNTRL
UPPER MI INTO THIS EVENING AS WINDS GRADUALLY VEER TO THE EAST...PER
HIGH RES MODELS. THE CLOUDS SHOULD ALSO KEEP TEMPS IN A NARROW RANGE
WITH HIGHS TODAY ONLY INTO THE MID AND UPPER 30S NORTH TO AROUND 40
SOUTH. WITH LINGERING CLOUDS TONIGHT...EXPECT MIN READINGS TOWARD
THE HIGHER END OF GUIDANCE IN THE UPPER 20S TO AROUND 30. HOWEVER...
IF SOME CLEARING DEVELOPS OVER THE SW TEMPS COULD FALL OFF QUICKLY
TO NEAR 20.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 443 AM EST SUN NOV 4 2012
THE 500MB WAVE CURRENTLY OVER SW CANADA WILL BE OVER THE CENTRAL
PLAINS BY DAYBREAK MONDAY...WITH A REINFORCING LOW SWINGING OVER SE
CANADA FROM HUDSON BAY. IN BETWEEN THESE 2 SYSTEMS UPPER MI WILL
REMAIN UNDER HIGH PRESSURE AT THE SFC AND ALOFT.
SW WINDS WILL BE ON THE INCREASE MONDAY NIGHT /850MB WINDS OF
20-30KTS WITH 850MB TEMPS RISING FROM -6C TO -2C/...IN ADVANCE OF
THE NEARING LOW FROM THE NW. PRECIPITATION WILL BEGIN LATE MONDAY
EVENING...AND BECOME LIKELY ACROSS THE ENTIRE AREA AROUND DAYBREAK
TUESDAY. AROUND AN INCH OF WET SNOW WILL BE POSSIBLE MONDAY NIGHT
INTO TUESDAY MORNING OVER THE HIGHER TERRAIN OF MQT...AND SE
BARAGA...AND NE IRON COUNTIES...WITH THE HELP OF A POCKET OF COOLER
AIR WITH SFC TEMPS EXPECTED TO REMAIN IN THE 30S THROUGH THE DAY
TUESDAY. S WINDS OFF LAKE MI COULD BECOME BREEZY AT TIMES OVER THE E
HALF NEAR THE GREAT LAKES SHORELINES...BUT BELOW ANY ADVISORY
VALUES. THE BULK OF THE MOISTURE SHOULD EXIT TUESDAY EVENING AS THE
S EXTENT OF THE ELONGATED LOW STRETCHING FROM NE MANITOBA THROUGH E
LAKE SUPERIOR EXITS EASTWARD AND TEMPORARILY GETS REPLACED BY A
RIDGE FROM THE SW. WHILE TIMING OF THE VARIOUS FCST MODELS IS STILL
A LITTLE UNCERTAIN...THEY ARE CONSISTENT WITH THE 500MB LOW OR
TROUGH DIGGING ACROSS THE UPPER GREAT LAKES TUESDAY NIGHT AND
INTENSIFYING OFF THE MID ATLANTIC AS IT MERGES WITH ANOTHER WAVE ON
THE S EDGE OF THE LARGER TROUGH THAT COVERS THE E HALF OF THE NATION.
LAKE EFFECT/LAKE ENHANCED CLOUDS AND PRECIP SHOULD LINGER INTO
WEDNESDAY...WITH THE POTENTIAL FOR BOTH RAIN AND SNOW CONTINUING.
OTHERWISE FOR THE END OF THE WORK WEEK...WITH HIGH PRESSURE OVERHEAD
IN BETWEEN A STRONGER SYSTEM OFF THE EASTERN SEABOARD AND ANOTHER
LOW DEVELOPING OFF THE ROCKIES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1232 PM EST SUN NOV 4 2012
STRONG INVERSION AROUND 3KFT ABOVE THE SURFACE HAS CONTINUED TO
TRAP CLOUDS OVER THE LAKE SUPERIOR REGION TODAY. WITH HIGH PRESSURE
TO THE NORTH CONTINUING LIGHT NORTHERLY FLOW THROUGH THIS EVENING
AND THEN VEERING TO THE EAST OVERNIGHT...EXPECT THE MVFR CLOUDS TO
REMAIN IN PLACE AT KCMX/KSAW. ALSO EXPECT OCCASIONAL SNOW SHOWERS
TO AFFECT KCMX THROUGH MUCH OF THE PERIOD...BUT ONLY THROUGH EARLY
EVENING AT KSAW SINCE WINDS WILL BEGIN TO TURN UNFAVORABLE. SINCE
CEILINGS ARE ALREADY AT MVFR LEVELS...DIDN/T TRY TO TIME THE BRIEF
VISIBILITY REDUCTIONS WITH THE SHOWERS.
AS FOR KIWD...DAYTIME MIXING IS STARTING TO BREAK UP CLOUDS AND
NORTHERN WISCONSIN AND EXPECT THAT TO CONTINUE NORTH TO THIS
AFTERNOON. AS HAS HAPPENED THE LAST TWO NIGHTS...EXPECT THE BREAKS
TO BE SHORT LIVED...AS LIGHT NORTHEAST AND THEN EAST FLOW WILL
LIKELY PUSH THE LOW CLOUDS BACK IN AFTER SUNSET. IF CLOUDS RETREAT
FARTHER NORTH THAN EXPECTED...THE CLOUDS MAY STRUGGLE TO DROP BACK
INTO KIWD WITH THE LIGHT WINDS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 443 AM EST SUN NOV 4 2012
AS HIGH PRESSURE OVER NORTHWEST ONTARIO SLIDES SOUTHEAST THROUGH THE
UPPER GREAT LAKES THROUGH MONDAY...EXPECT WINDS TO BE LIGHT AND LESS
THAN 15KTS. A LOW PRESSURE SYSTEM MOVING THROUGH CENTRAL CANADA ON
TUESDAY WILL SWEEP A SURFACE TROUGH ACROSS THE UPPER GREAT LAKES
REGION AND BRING INCREASING SOUTHWESTERLY WINDS TO 20-30 KTS. A WEAK
HIGH PRESSURE RIDGE WILL THEN SLIDE INTO THE UPPER GREAT LAKES
WEDNESDAY AFTERNOON AND REMAIN INTO FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...SRF
SHORT TERM...JLB
LONG TERM...KF
AVIATION...SRF
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1138 AM EST SUN NOV 4 2012
.UPDATE...
ISSUED AT 1138 AM EST SUN NOV 4 2012
BASED OFF LATEST RADAR TRENDS AND HIGH RESOLUTION MODEL
GUIDANCE...HAVE BUMPED UP THE ISOLATED FLURRIES TO ISOLATED SNOW
SHOWERS /MIXED WITH RAIN THIS AFTERNOON NEAR THE LAKESHORE/. EXPECT
A SIMILAR SITUATION TO OCCUR THIS AFTERNOON AS YESTERDAY
AFTERNOON...WHERE DIURNAL AFFECTS WERE ABLE TO LIFT THE INVERSION A
FEW HUNDRED FEET AND ENOUGH TO ENABLE ISOLATED SHOWERS WITH THE LAKE
SUPERIOR SFC-H925 DELTA-T OF 13. HAVE CONTINUED THIS OVER THE NORTH
CENTRAL AND KEWEENAW THROUGH THE NIGHT AND INTO TOMORROW
MORNING...LARGELY FOLLOWING THE SLOWLY VEERING LIGHT FLOW FROM NORTH
TO EAST THROUGH TOMORROW AFTERNOON.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 443 AM EST SUN NOV 4 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A LONGWAVE PATTERN WITH A
MID/UPPER LEVEL RIDGE INTO THE WRN CONUS AND A TROUGH OVER THE EAST.
A SHRTWV TROUGH WAS LOCATED OVER NE IA WHILE A RIDGE EXTENDED FROM
NORTH DAKOTA INTO NE MANITOBA LEAVING WEAK NRLY FLOW THROUGH THE NRN
GREAT LAKES. AT THE SFC...HIGH PRES EXTENDED FROM NRN MANITOBA AND
NW ONTARIO THROUGH WRN LAKE SUPERIOR INTO WI RESULTING IN ACYC NRLY
FLOW ACROSS LAKE SUPERIOR AND UPPER MI. SHALLOW MOISTURE TRAPPED
BELOW A 2K-3K FT INVERSION WITH 925 MB TEMPS TO AROUND -6C HAS
PROVIDED ENOUGH INSTABILITY TO SUPPORT ISOLATED LAKE EFFECT FLURRIES
INTO N CNTRL UPPER MI. OTHERWISE...IR LOOP SHOWED LOW CLOUDS ACROSS
NRN ONTARIO THROUGH THE CWA.
SATELLITE TRENDS AND MODELS 925 RH SUGGEST THAT...SIMILAR TO
YESTERDAY...THE LOW CLOUDS WILL PERSIST OVER THE AREA GIVEN LITTLE
CHANGE IN THE TEMP PROFILE AND ONLY A GRADUAL WIND SHIFT. THERE MAY
BE SOME AFTERNOON CLEARING AGAIN OVER THE SOUTHWEST...WHERE MIXING
MAY HELP PUSH THE EDGE OF THE CLOUDS BACK TO THE NORTHEAST. EVEN
THOUGH INSTABILITY AND THE WIND FIELDS REMAIN WEAK...SOME
ISOLATED/INTERMITTENT FLURRIES WILL REMAIN POSSIBLE OVER N CNTRL
UPPER MI INTO THIS EVENING AS WINDS GRADUALLY VEER TO THE EAST...PER
HIGH RES MODELS. THE CLOUDS SHOULD ALSO KEEP TEMPS IN A NARROW RANGE
WITH HIGHS TODAY ONLY INTO THE MID AND UPPER 30S NORTH TO AROUND 40
SOUTH. WITH LINGERING CLOUDS TONIGHT...EXPECT MIN READINGS TOWARD
THE HIGHER END OF GUIDANCE IN THE UPPER 20S TO AROUND 30. HOWEVER...
IF SOME CLEARING DEVELOPS OVER THE SW TEMPS COULD FALL OFF QUICKLY
TO NEAR 20.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 443 AM EST SUN NOV 4 2012
THE 500MB WAVE CURRENTLY OVER SW CANADA WILL BE OVER THE CENTRAL
PLAINS BY DAYBREAK MONDAY...WITH A REINFORCING LOW SWINGING OVER SE
CANADA FROM HUDSON BAY. IN BETWEEN THESE 2 SYSTEMS UPPER MI WILL
REMAIN UNDER HIGH PRESSURE AT THE SFC AND ALOFT.
SW WINDS WILL BE ON THE INCREASE MONDAY NIGHT /850MB WINDS OF
20-30KTS WITH 850MB TEMPS RISING FROM -6C TO -2C/...IN ADVANCE OF
THE NEARING LOW FROM THE NW. PRECIPITATION WILL BEGIN LATE MONDAY
EVENING...AND BECOME LIKELY ACROSS THE ENTIRE AREA AROUND DAYBREAK
TUESDAY. AROUND AN INCH OF WET SNOW WILL BE POSSIBLE MONDAY NIGHT
INTO TUESDAY MORNING OVER THE HIGHER TERRAIN OF MQT...AND SE
BARAGA...AND NE IRON COUNTIES...WITH THE HELP OF A POCKET OF COOLER
AIR WITH SFC TEMPS EXPECTED TO REMAIN IN THE 30S THROUGH THE DAY
TUESDAY. S WINDS OFF LAKE MI COULD BECOME BREEZY AT TIMES OVER THE E
HALF NEAR THE GREAT LAKES SHORELINES...BUT BELOW ANY ADVISORY
VALUES. THE BULK OF THE MOISTURE SHOULD EXIT TUESDAY EVENING AS THE
S EXTENT OF THE ELONGATED LOW STRETCHING FROM NE MANITOBA THROUGH E
LAKE SUPERIOR EXITS EASTWARD AND TEMPORARILY GETS REPLACED BY A
RIDGE FROM THE SW. WHILE TIMING OF THE VARIOUS FCST MODELS IS STILL
A LITTLE UNCERTAIN...THEY ARE CONSISTENT WITH THE 500MB LOW OR
TROUGH DIGGING ACROSS THE UPPER GREAT LAKES TUESDAY NIGHT AND
INTENSIFYING OFF THE MID ATLANTIC AS IT MERGES WITH ANOTHER WAVE ON
THE S EDGE OF THE LARGER TROUGH THAT COVERS THE E HALF OF THE NATION.
LAKE EFFECT/LAKE ENHANCED CLOUDS AND PRECIP SHOULD LINGER INTO
WEDNESDAY...WITH THE POTENTIAL FOR BOTH RAIN AND SNOW CONTINUING.
OTHERWISE FOR THE END OF THE WORK WEEK...WITH HIGH PRESSURE OVERHEAD
IN BETWEEN A STRONGER SYSTEM OFF THE EASTERN SEABOARD AND ANOTHER
LOW DEVELOPING OFF THE ROCKIES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 644 AM EST SUN NOV 4 2012
WITH LIGHT NNE FLOW OFF OF LAKE SUPERIOR ON THE SOUTHERN FLANK OF
HIGH PRES IN ONTARIO AND A SHARP SUBSIDENCE INVERSION...EXPECT
MVFR CIGS TO PERSIST THIS FCST PERIOD. THE BEST CHANCE FOR VFR
CONDITIONS WILL BE THIS AFTERNOON AT IWD...WHERE THE COMBINATION OF
DIURNAL HEATING AND DOWNSLOPING NE FLOW WILL HAVE A BETTER CHANCE OF
DISSIPATING THE LOW CLOUDS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 443 AM EST SUN NOV 4 2012
AS HIGH PRESSURE OVER NORTHWEST ONTARIO SLIDES SOUTHEAST THROUGH THE
UPPER GREAT LAKES THROUGH MONDAY...EXPECT WINDS TO BE LIGHT AND LESS
THAN 15KTS. A LOW PRESSURE SYSTEM MOVING THROUGH CENTRAL CANADA ON
TUESDAY WILL SWEEP A SURFACE TROUGH ACROSS THE UPPER GREAT LAKES
REGION AND BRING INCREASING SOUTHWESTERLY WINDS TO 20-30 KTS. A WEAK
HIGH PRESSURE RIDGE WILL THEN SLIDE INTO THE UPPER GREAT LAKES
WEDNESDAY AFTERNOON AND REMAIN INTO FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...SRF
SHORT TERM...JLB
LONG TERM...KF
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
645 AM EST SUN NOV 4 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 443 AM EST SUN NOV 4 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A LONGWAVE PATTERN WITH A
MID/UPPER LEVEL RIDGE INTO THE WRN CONUS AND A TROUGH OVER THE EAST.
A SHRTWV TROUGH WAS LOCATED OVER NE IA WHILE A RIDGE EXTENDED FROM
NORTH DAKOTA INTO NE MANITOBA LEAVING WEAK NRLY FLOW THROUGH THE NRN
GREAT LAKES. AT THE SFC...HIGH PRES EXTENDED FROM NRN MANITOBA AND
NW ONTARIO THROUGH WRN LAKE SUPERIOR INTO WI RESULTING IN ACYC NRLY
FLOW ACROSS LAKE SUPERIOR AND UPPER MI. SHALLOW MOISTURE TRAPPED
BELOW A 2K-3K FT INVERSION WITH 925 MB TEMPS TO AROUND -6C HAS
PROVIDED ENOUGH INSTABILITY TO SUPPORT ISOLATED LAKE EFFECT FLURRIES
INTO N CNTRL UPPER MI. OTHERWISE...IR LOOP SHOWED LOW CLOUDS ACROSS
NRN ONTARIO THROUGH THE CWA.
SATELLITE TRENDS AND MODELS 925 RH SUGGEST THAT...SIMILAR TO
YESTERDAY...THE LOW CLOUDS WILL PERSIST OVER THE AREA GIVEN LITTLE
CHANGE IN THE TEMP PROFILE AND ONLY A GRADUAL WIND SHIFT. THERE MAY
BE SOME AFTERNOON CLEARING AGAIN OVER THE SOUTHWEST...WHERE MIXING
MAY HELP PUSH THE EDGE OF THE CLOUDS BACK TO THE NORTHEAST. EVEN
THOUGH INSTABILITY AND THE WIND FIELDS REMAIN WEAK...SOME
ISOLATED/INTERMITTENT FLURRIES WILL REMAIN POSSIBLE OVER N CNTRL
UPPER MI INTO THIS EVENING AS WINDS GRADUALLY VEER TO THE EAST...PER
HIGH RES MODELS. THE CLOUDS SHOULD ALSO KEEP TEMPS IN A NARROW RANGE
WITH HIGHS TODAY ONLY INTO THE MID AND UPPER 30S NORTH TO AROUND 40
SOUTH. WITH LINGERING CLOUDS TONIGHT...EXPECT MIN READINGS TOWARD
THE HIGHER END OF GUIDANCE IN THE UPPER 20S TO AROUND 30. HOWEVER...
IF SOME CLEARING DEVELOPS OVER THE SW TEMPS COULD FALL OFF QUICKLY
TO NEAR 20.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 443 AM EST SUN NOV 4 2012
THE 500MB WAVE CURRENTLY OVER SW CANADA WILL BE OVER THE CENTRAL
PLAINS BY DAYBREAK MONDAY...WITH A REINFORCING LOW SWINGING OVER SE
CANADA FROM HUDSON BAY. IN BETWEEN THESE 2 SYSTEMS UPPER MI WILL
REMAIN UNDER HIGH PRESSURE AT THE SFC AND ALOFT.
SW WINDS WILL BE ON THE INCREASE MONDAY NIGHT /850MB WINDS OF
20-30KTS WITH 850MB TEMPS RISING FROM -6C TO -2C/...IN ADVANCE OF
THE NEARING LOW FROM THE NW. PRECIPITATION WILL BEGIN LATE MONDAY
EVENING...AND BECOME LIKELY ACROSS THE ENTIRE AREA AROUND DAYBREAK
TUESDAY. AROUND AN INCH OF WET SNOW WILL BE POSSIBLE MONDAY NIGHT
INTO TUESDAY MORNING OVER THE HIGHER TERRAIN OF MQT...AND SE
BARAGA...AND NE IRON COUNTIES...WITH THE HELP OF A POCKET OF COOLER
AIR WITH SFC TEMPS EXPECTED TO REMAIN IN THE 30S THROUGH THE DAY
TUESDAY. S WINDS OFF LAKE MI COULD BECOME BREEZY AT TIMES OVER THE E
HALF NEAR THE GREAT LAKES SHORELINES...BUT BELOW ANY ADVISORY
VALUES. THE BULK OF THE MOISTURE SHOULD EXIT TUESDAY EVENING AS THE
S EXTENT OF THE ELONGATED LOW STRETCHING FROM NE MANITOBA THROUGH E
LAKE SUPERIOR EXITS EASTWARD AND TEMPORARILY GETS REPLACED BY A
RIDGE FROM THE SW. WHILE TIMING OF THE VARIOUS FCST MODELS IS STILL
A LITTLE UNCERTAIN...THEY ARE CONSISTENT WITH THE 500MB LOW OR
TROUGH DIGGING ACROSS THE UPPER GREAT LAKES TUESDAY NIGHT AND
INTENSIFYING OFF THE MID ATLANTIC AS IT MERGES WITH ANOTHER WAVE ON
THE S EDGE OF THE LARGER TROUGH THAT COVERS THE E HALF OF THE NATION.
LAKE EFFECT/LAKE ENHANCED CLOUDS AND PRECIP SHOULD LINGER INTO
WEDNESDAY...WITH THE POTENTIAL FOR BOTH RAIN AND SNOW CONTINUING.
OTHERWISE FOR THE END OF THE WORK WEEK...WITH HIGH PRESSURE OVERHEAD
IN BETWEEN A STRONGER SYSTEM OFF THE EASTERN SEABOARD AND ANOTHER
LOW DEVELOPING OFF THE ROCKIES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 644 AM EST SUN NOV 4 2012
WITH LIGHT NNE FLOW OFF OF LAKE SUPERIOR ON THE SOUTHERN FLANK OF
HIGH PRES IN ONTARIO AND A SHARP SUBSIDENCE INVERSION...EXPECT
MVFR CIGS TO PERSIST THIS FCST PERIOD. THE BEST CHANCE FOR VFR
CONDITIONS WILL BE THIS AFTERNOON AT IWD...WHERE THE COMBINATION OF
DIURNAL HEATING AND DOWNSLOPING NE FLOW WILL HAVE A BETTER CHANCE OF
DISSIPATING THE LOW CLOUDS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 443 AM EST SUN NOV 4 2012
AS HIGH PRESSURE OVER NORTHWEST ONTARIO SLIDES SOUTHEAST THROUGH THE
UPPER GREAT LAKES THROUGH MONDAY...EXPECT WINDS TO BE LIGHT AND LESS
THAN 15KTS. A LOW PRESSURE SYSTEM MOVING THROUGH CENTRAL CANADA ON
TUESDAY WILL SWEEP A SURFACE TROUGH ACROSS THE UPPER GREAT LAKES
REGION AND BRING INCREASING SOUTHWESTERLY WINDS TO 20-30 KTS. A WEAK
HIGH PRESSURE RIDGE WILL THEN SLIDE INTO THE UPPER GREAT LAKES
WEDNESDAY AFTERNOON AND REMAIN INTO FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
447 AM EST SUN NOV 4 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 443 AM EST SUN NOV 4 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A LONGWAVE PATTERN WITH A
MID/UPPER LEVEL RIDGE INTO THE WRN CONUS AND A TROUGH OVER THE EAST.
A SHRTWV TROUGH WAS LOCATED OVER NE IA WHILE A RIDGE EXTENDED FROM
NORTH DAKOTA INTO NE MANITOBA LEAVING WEAK NRLY FLOW THROUGH THE NRN
GREAT LAKES. AT THE SFC...HIGH PRES EXTENDED FROM NRN MANITOBA AND
NW ONTARIO THROUGH WRN LAKE SUPERIOR INTO WI RESULTING IN ACYC NRLY
FLOW ACROSS LAKE SUPERIOR AND UPPER MI. SHALLOW MOISTURE TRAPPED
BELOW A 2K-3K FT INVERSION WITH 925 MB TEMPS TO AROUND -6C HAS
PROVIDED ENOUGH INSTABILITY TO SUPPORT ISOLATED LAKE EFFECT FLURRIES
INTO N CNTRL UPPER MI. OTHERWISE...IR LOOP SHOWED LOW CLOUDS ACROSS
NRN ONTARIO THROUGH THE CWA.
SATELLITE TRENDS AND MODELS 925 RH SUGGEST THAT...SIMILAR TO
YESTERDAY...THE LOW CLOUDS WILL PERSIST OVER THE AREA GIVEN LITTLE
CHANGE IN THE TEMP PROFILE AND ONLY A GRADUAL WIND SHIFT. THERE MAY
BE SOME AFTERNOON CLEARING AGAIN OVER THE SOUTHWEST...WHERE MIXING
MAY HELP PUSH THE EDGE OF THE CLOUDS BACK TO THE NORTHEAST. EVEN
THOUGH INSTABILITY AND THE WIND FIELDS REMAIN WEAK...SOME
ISOLATED/INTERMITTENT FLURRIES WILL REMAIN POSSIBLE OVER N CNTRL
UPPER MI INTO THIS EVENING AS WINDS GRADUALLY VEER TO THE EAST...PER
HIGH RES MODELS. THE CLOUDS SHOULD ALSO KEEP TEMPS IN A NARROW RANGE
WITH HIGHS TODAY ONLY INTO THE MID AND UPPER 30S NORTH TO AROUND 40
SOUTH. WITH LINGERING CLOUDS TONIGHT...EXPECT MIN READINGS TOWARD
THE HIGHER END OF GUIDANCE IN THE UPPER 20S TO AROUND 30. HOWEVER...
IF SOME CLEARING DEVELOPS OVER THE SW TEMPS COULD FALL OFF QUICKLY
TO NEAR 20.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 443 AM EST SUN NOV 4 2012
THE 500MB WAVE CURRENTLY OVER SW CANADA WILL BE OVER THE CENTRAL
PLAINS BY DAYBREAK MONDAY...WITH A REINFORCING LOW SWINGING OVER SE
CANADA FROM HUDSON BAY. IN BETWEEN THESE 2 SYSTEMS UPPER MI WILL
REMAIN UNDER HIGH PRESSURE AT THE SFC AND ALOFT.
SW WINDS WILL BE ON THE INCREASE MONDAY NIGHT /850MB WINDS OF
20-30KTS WITH 850MB TEMPS RISING FROM -6C TO -2C/...IN ADVANCE OF
THE NEARING LOW FROM THE NW. PRECIPITATION WILL BEGIN LATE MONDAY
EVENING...AND BECOME LIKELY ACROSS THE ENTIRE AREA AROUND DAYBREAK
TUESDAY. AROUND AN INCH OF WET SNOW WILL BE POSSIBLE MONDAY NIGHT
INTO TUESDAY MORNING OVER THE HIGHER TERRAIN OF MQT...AND SE
BARAGA...AND NE IRON COUNTIES...WITH THE HELP OF A POCKET OF COOLER
AIR WITH SFC TEMPS EXPECTED TO REMAIN IN THE 30S THROUGH THE DAY
TUESDAY. S WINDS OFF LAKE MI COULD BECOME BREEZY AT TIMES OVER THE E
HALF NEAR THE GREAT LAKES SHORELINES...BUT BELOW ANY ADVISORY
VALUES. THE BULK OF THE MOISTURE SHOULD EXIT TUESDAY EVENING AS THE
S EXTENT OF THE ELONGATED LOW STRETCHING FROM NE MANITOBA THROUGH E
LAKE SUPERIOR EXITS EASTWARD AND TEMPORARILY GETS REPLACED BY A
RIDGE FROM THE SW. WHILE TIMING OF THE VARIOUS FCST MODELS IS STILL
A LITTLE UNCERTAIN...THEY ARE CONSISTENT WITH THE 500MB LOW OR
TROUGH DIGGING ACROSS THE UPPER GREAT LAKES TUESDAY NIGHT AND
INTENSIFYING OFF THE MID ATLANTIC AS IT MERGES WITH ANOTHER WAVE ON
THE S EDGE OF THE LARGER TROUGH THAT COVERS THE E HALF OF THE NATION.
LAKE EFFECT/LAKE ENHANCED CLOUDS AND PRECIP SHOULD LINGER INTO
WEDNESDAY...WITH THE POTENTIAL FOR BOTH RAIN AND SNOW CONTINUING.
OTHERWISE FOR THE END OF THE WORK WEEK...WITH HIGH PRESSURE OVERHEAD
IN BETWEEN A STRONGER SYSTEM OFF THE EASTERN SEABOARD AND ANOTHER
LOW DEVELOPING OFF THE ROCKIES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 125 AM EDT SUN NOV 4 2012
WITH LIGHT NNE FLOW OFF LK SUP ON SRN FLANK OF HI PRES IN ONTARIO
AND SHARP SUBSIDENCE INVRN SHOWN ON SEVERAL LOCAL 00Z RAOBS...EXPECT
MVFR CIGS TO DOMINATE THIS FCST PERIOD. THE BEST CHC FOR VFR
CONDITIONS WL BE SUN AFTN AT IWD...WHERE THE COMBINATION OF DIURNAL
HEATING/DOWNSLOPING NE FLOW WL HAVE A BETTER CHC OF DISSIPATING THE
LO CLD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 443 AM EST SUN NOV 4 2012
AS HIGH PRESSURE OVER NORTHWEST ONTARIO SLIDES SOUTHEAST THROUGH THE
UPPER GREAT LAKES THROUGH MONDAY...EXPECT WINDS TO BE LIGHT AND LESS
THAN 15KTS. A LOW PRESSURE SYSTEM MOVING THROUGH CENTRAL CANADA ON
TUESDAY WILL SWEEP A SURFACE TROUGH ACROSS THE UPPER GREAT LAKES
REGION AND BRING INCREASING SOUTHWESTERLY WINDS TO 20-30 KTS. A WEAK
HIGH PRESSURE RIDGE WILL THEN SLIDE INTO THE UPPER GREAT LAKES
WEDNESDAY AFTERNOON AND REMAIN INTO FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
116 AM EDT SUN NOV 4 2012
.AVIATION...
//DISCUSSION...
PERIOD OF STRATUS EROSION SEEMS TO HAVE ENDED AND CIGS BETWEEN 2500
AND 3500 FEET AS FILLING BACK IN WITHIN LIGHT WIND REGIME AND MOST
LIKELY AN ASSIST BY WEAK VVELS IN ADVANCE OF APPROACHING SHORTWAVE.
WILL DO AN ABOUT FACE AND INCLUDE MVFR CIGS INTO THE 12Z-14Z PERIOD
AND THEN BRING SOME CLEARING...OF LOWER LEVEL MOISTURE...IN THE WAKE
OF THIS WAVE. THIS IS SOMEWHAT IFFY GIVEN CONTINUED LIGHT NORTH
FLOW.
AT DTW...SCT-BKN 3000-3500 FOOT STRATUS WILL LIKELY FILL IN FURTHER
OVERNIGHT AND PERSIST INTO SUNDAY MORNING BEFORE BREAKING UP AGAIN
SOMEWHAT WITHIN WEAK SUBSIDENCE IN WAKE OF A PASSING SHORTWAVE WHICH
WILL PROGRESS THROUGH THE OHIO VALLEY DURING THE DAY.
//DTW THRESHOLD THREATS...
* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET AT TIMES INTO EARLY
SUNDAY MORNING.
&&
.PREV DISCUSSION...ISSUED 337 PM EDT SAT NOV 3 2012
SHORT TERM...THIS EVENING AND TONIGHT
A STABLE SURFACE RIDGE WILL MAINTAIN A FIRM GRASP OF SOUTHEASTERN
MICHIGAN THROUGHOUT THE NIGHT. NAM AND RAP ARE SHOWING A RIBBON OF
VORTICITY ENERGY SHEARING OUT OF THE ND/MN ANOMALY...STRINGING INTO
SOUTHERN LOWER MICHIGAN FROM THE WEST. MODEL SOLUTIONS ARE ALSO
DEPICTING A WING OF 700-500MB FRONTOGENSIS SLIDING OVER THE CWA.
THIS FORCING IS NOW DRIVING THE REFLECTIVITY RETURNS OVER PORTIONS
OF SOUTHERN WISCONSIN/ILLINOIS/LAKE MICHIGAN. FORECAST SOUNDINGS
SHOW A SATURATED/WEAK LAPSE RATE LAYER BETWEEN 15-20 KFT AGL
OVERNIGHT DUE TO THIS FORCING...NECESSITATING AN INCREASED MENTION
OF CLOUDS. A DEEP DRY SLAB WILL REMAIN IN PLACE BETWEEN 4-15 KFT
AGL...WITH NO REAL SHOT AT ANY PRECIPITATION. THIS IS IN AGREEMENT
WITH THE LACK OF SFC HYDROMETEORS BEING REPORTED IN UPSTREAM
OBSERVATIONS.
GIVEN THE PERSISTENCE OF THE NORTHERLY FLOW TRAJECTORY...WILL BUMP
TEMPERATURES UPWARD A DEGREE OR TWO FOR THE FAR EASTERN CWA.
TEMPERATURES LAST NIGHT WERE ABLE TO HANG ON FOR A FEW
LOCATIONS...MOST NOTABLY THE BULK OF THE THUMB. OTHERWISE...DO NOT
WANT TO GET TOO CARRIED AWAY WITH RAISING MINIMUMS...GIVEN THE COLD
SURFACE RIDGE AND NOTHING MORE THAN HIGH CLOUD CONCERNS.
LONG TERM...SUNDAY THROUGH NEXT SATURDAY
A SURFACE RIDGE LOCATED OVER THE WESTERN GREAT LAKES WILL MAINTAIN
CONTROL OVER THE WEATHER ACROSS THE REGION THROUGH THE PERIOD AS IT
SLOWLY MOVES EAST THROUGH THE GREAT LAKES THROUGH MONDAY. COOL AIR
ALOFT COMBINED WITH SINKING MOTION FROM THE HIGH WILL KEEP MIXING
HEIGHTS SHALLOW DURING THIS PERIOD...MAINTAINING COLDER THAN NORMAL
TEMPERATURES THROUGH EARLY NEXT WEEK. ONE INTERESTING FEATURE THE
NWP MODELS CONTINUE TO KEY IN ON IS LAKE EFFECT OVER SOUTHERN LAKE
HURON BRINGING LIGHT PRECIPITATION TO THE THUMB REGION SUNDAY
THROUGH MONDAY. HOWEVER CLOSER INSPECTION SHOWS A VERY SHALLOW
INVERSION LEVEL AROUND 3-4K FEET WITH ABUNDANT DRY AIR ABOVE 850 MB.
THE SHALLOW INVERSION HEIGHTS...DRY AIR AND RATHER UNIMPRESSIVE
DELTA T VALUES LEND ITSELF TO A CONTINUED DRY FORECAST WITH
INCREASED CLOUDINESS OVER THIS AREA BEING THE EXPECTED RESULT OF THE
FLOW OFF LAKE HURON DURING THIS PERIOD.
AS THE HIGH MOVES OFF TO THE EAST...A TROUGH WILL DIG INTO THE
WESTERN GREAT LAKES REGION ON TUESDAY...TRACKING THROUGH THE CENTRAL
GREAT LAKES TUESDAY NIGHT AND LIFTING OUT ON WEDNESDAY. THIS
SHORTWAVE WILL BE OF PACIFIC ORIGIN...WITH NO WAY TO TAP INTO THE
MOISTURE FROM THE LARGE NOREASTER TRACKING ALONG THE ATLANTIC
SEABOARD DURING THIS SAME TIME PERIOD. THEREFORE WILL CONTINUE TO
MAINTAIN LOW CHANCY POPS DURING THIS PERIOD AS THIS SYSTEM WILL BE
SEVERELY MOISTURE STARVED. TEMPERATURES WILL CONTINUE TO BE ON THE
COOL SIDE AS THE SYSTEM FAILS TO PULL IN WARMER AIR FROM THE SOUTH
INTO THE CENTRAL GREAT LAKES.
LARGE SCALE RIDGING WILL DOMINATE THE WEATHER ACROSS THE GREAT LAKES
DURING THE LATE PART OF THE WORK WEEK AND INTO EARLY NEXT
WEEKEND...KEEPING THE WEATHER DRY. THE RIDGING WILL ALSO PULL IN
SOME WARMER AIR FROM THE WEST AS 850 MB TEMPERATURES WARM FROM THE
SINGLE DIGITS BELOW ZERO TO THE SINGLE DIGITS ABOVE ZERO AND
EVENTUALLY AROUND +10 CELSIUS BY SATURDAY. THIS WILL BRING A GRADUAL
WARMUP THROUGH EARLY NEXT WEEKEND AS NEXT SATURDAYS HIGHS ARE
FORECAST TO EXCEED NORMAL LEVELS.
MARINE...
NORTHERLY WINDS WILL DECREASE TO 15 KNOTS OR BELOW BY LATE
EVENING...HOWEVER GIVEN THE CONTINUED NORTHERLY DIRECTION...WAVE
HEIGHTS WILL BE SLOW TO SUBSIDE. WAVE HEIGHTS LOOK TO FALL BELOW 5
FEET OVERNIGHT. FAIRLY QUIET CONDITIONS ARE THEN EXPECTED LATE
SUNDAY THROUGH MONDAY AS THE HIGH SINKS DOWN OVER THE AREA.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...
SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT
SANILAC...UNTIL 4 AM SUNDAY.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....DG
SHORT TERM...CB
LONG TERM....KURIMSKI
MARINE.......CB
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
233 PM CST SUN NOV 4 2012
.SHORT TERM...
ISSUED AT 233 PM CST SUN NOV 4 2012
(TONIGHT)
POTENT LITTLE SHORTWAVE IS DEVELOPING OVER NORTHEAST MONTANA...AND
WILL DIVE SOUTHEAST THROUGH THE GREAT PLAINS TONIGHT. THE SURFACE
REFLECTION OF THIS WAVE WILL LIKEWISE DROP SOUTHEAST INTO THE PLAINS
AND LINK UP WITH A BROAD/RELATIVELY WEAK AREA OF LOW PRESSURE
CURRENTLY SITTING OVER KANSAS. THE COMBINED SURFACE TROF WILL
STRENGTHEN SLIGHTLY AS IT MOVES INTO NORTHWEST MISSOURI LATE
TONIGHT. MODELS ARE IN GOOD AGREEMENT IN SPREADING A SWATH OF RAIN
OUT SOUTHEAST AHEAD OF THE SHORTWAVE. THE ONSET OF PRECIP LOOKS
FASTER THAN PREVIOUSLY THOUGHT...THE HRRR IS ESPECIALLY FAST
BRINGING PRECIP INTO CENTRAL MO AS EARLY AS 03Z...AND SPREADING TO
NEAR THE MISSISSIPPI RIVER BY 06Z. AM STICKING CLOSER TO THE
OPERATIONAL NAM AND GFS SOLUTIONS WHICH ARE 3-6HRS SLOWER...BUT WILL
BRIEF THE EVENING SHIFT TO WATCH FOR A FASTER ONSET OF RAIN.
CARNEY
&&
.LONG TERM...
ISSUED AT 233 PM CST SUN NOV 4 2012
(MONDAY THROUGH SUNDAY)
NORTHWEST FLOW ALIVE AND WELL ACROSS THE CENTER OF THE NATION AS A
DEEP LONGWAVE TROF CONTINUES TO BE CARVED OUT ACROSS THE EASTERN
CONUS. SHORTWAVE OF INTEREST IN THE SHORT TERM WILL CONTINUE TO DIVE
SOUTHEAST INTO THE BASE OF THIS LONGWAVE TROF AND BE RESPONSIBLE FOR
THE DEVELOPMENT OF A POWERFUL STORM SYSTEM THAT WILL MOVE UP THE
EAST COAST DURING THE MIDDLE PORTION OF THIS WEEK. THIS WILL
CERTAINLY BE THE NATIONS WEATHER STORY...AS THE NOR`EASTER BRINGS
STRONG WIND...RAIN...AND EVEN SOME WINTER WEATHER TO AREAS STILL
REELING FROM SANDY.
MONDAY AND MONDAY NIGHT...
MODEL GUIDANCE IN VERY GOOD AGREEMENT REGARDING THE TRACK OF THE
SHORTWAVE ACROSS MISSOURI. AREA OF LIGHT RAIN WILL WORK ITS WAY
SOUTH ACROSS THE REGION WITH THICK CLOUD COVER AND CHILLY
TEMPERATURES. HAVE WENT A DEGREE OR TWO BELOW THE LOWEST MODEL
GUIDANCE. RAIN SHOULD PUSH SOUTH OF THE AREA BY MONDAY NIGHT...BUT
CLOUDS WILL HANG TOUGH IN THE WAKE OF THIS SYSTEM. HAVE KEPT
TEMPERATURES WARMER THAN GUIDANCE WOULD SUGGEST...WITH A LIMITED
DIURNAL TEMPERATURE SWING.
TUESDAY AND WEDNESDAY...
A FINAL SHORTWAVE...THE CABOOSE...WILL TRACK ACROSS THE WESTERN
GREAT LAKES...PUSHING A FINAL COLD FRONT ACROSS THE AREA. LIMITED
MOISTURE AND AN EASTERN TRACK TO THE DISTURBANCE KEEPS POPS AT
SLIGHT CHANCE AND CONFINED TO ILLINOIS COUNTIES. SURFACE RIDGE OF
HIGH PRESSURE WILL THEN BUILD ACROSS THE CWA ON WEDNESDAY WITH DRY
WEATHER AND SEASONAL TEMPERATURES.
THURSDAY THROUGH SUNDAY...
THE UPPER AIR PATTERN WILL FINALLY TRANSITION BY WEEKS END AS A
MASSIVE STORM SYSTEM CARVES A LONGWAVE TROF ACROSS THE WESTERN CONUS
WHICH HELPS AMPLIFY A RIDGE DOWNSTREAM ACROSS THE EASTERN CONUS. THE
END RESULT WILL BE SOUTHWEST FLOW ACROSS THE MIDWEST AND ABOVE
NORMAL TEMPERATURES. THIS LARGE UPPER TROF WILL BE PROGRESSIVE WITH
RAIN CHANCES INCREASING SUNDAY AND SUNDAY NIGHT.
CVKING
&&
.AVIATION...
ISSUED AT 1141 AM CST SUN NOV 4 2012
VFR FLIGHT CONDITIONS AND LIGHT VARIABLE WIND WILL PREVAIL THIS
AFTERNOON AS HIGH PRESSURE DRIFTS ACROSS THE AREA. THERE MAY BE A
SPRINKLE OR TWO OUT OF A MID CLOUD DECK STRETCHING ACROSS
NORTHEAST MISSOURI...BUT EXPECT NO IMPACTS FROM THIS VERY LIGHT
PRECIPITATION. A STORM WILL MOVE FROM THE NORTHERN GREAT PLAINS
ACROSS THE MISSOURI VALLEY TONIGHT...BRINGING RAIN AND MVFR
CIGS/VSBYS TO THE AREA BY MONDAY MORNING. WOULD NOT BE SURPRISED
TO SEE AREAS OF IFR CIGS DEVELOP BEFORE 18Z MONDAY.
SPECIFICS FOR KSTL...
VFR FLIGHT CONDITIONS AND LIGHT VARIABLE WIND WILL PREVAIL AT
LAMBERT THIS AFTERNOON AS HIGH PRESSURE DRIFTS ACROSS THE AREA. A
STORM WILL MOVE FROM THE NORTHERN GREAT PLAINS ACROSS THE MISSOURI
VALLEY TONIGHT...BRINGING RAIN AND MVFR CIGS/VSBYS TO THE TERMINAL
BETWEEN 12Z AND 14Z MONDAY MORNING. WHILE NO IFR CONDITIONS ARE IN
THE TAF AT THIS TIME...WOULD NOT BE SURPRISED TO SEE CIGS FALL TO
IFR AFTER 18Z MONDAY AS THE STORM SYSTEM PASSES JUST TO THE WEST
OF THE TERMINAL.
CARNEY
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
833 PM CST MON NOV 5 2012
.UPDATE...
ISOLATED SHOWERS CONTINUE TO DEVELOP ACROSS WRN AND CNTL SD. IT
LOOKS LIKE THERE IS ENOUGH MOISTURE ALOFT FOR SOME RAIN AT THE SFC
BASED ON 00Z SOUNDINGS. OBSERVED STORM MOTION SHOULD CARRY THE
LIGHT RAIN THRU NCNTL NEB OVERNIGHT. ALSO RAISED TEMPS A CATEGORY
AS FAIRLY DENSE MID AND UPPER LEVEL CLOUDS SHOULD CONTINUE OVERNIGHT.
&&
.PREV DISCUSSION... /ISSUED 547 PM CST MON NOV 5 2012/
UPDATE...
AVIATION...
VFR IS EXPECTED MOST AREAS TONIGHT AND TUESDAY.
A COLD FRONT WILL MOVE THROUGH TONIGHT WITH WINDS INCREASING AFTER
15Z TO 32025G35KT ACROSS NCNTL NEB EAST OF HIGHWAY 83.
SPRINKLES HAVE DEVELOPED AHEAD OF THE FRONT THIS EVENING. VFR IS
EXPECTED BENEATH THOSE RADAR RETURNS. ALSO...THE BANK OF MVFR CIGS
ACROSS NCNTL NEB GETS SHOVED EAST AS THE COLD FRONT APPROACHES
LATE TONIGHT...09Z- 12Z. NOTE THE RUC SUGGESTS SOME POTENTIAL FOR
MVFR CIGS LATE TONIGHT WITH THE COLD FRONT. FOR NOW PLAN ON VFR.
BEST GUESS ON MVFR CAN BE MADE AS THE FRONT GETS CLOSER THIS
EVENING.
PREV DISCUSSION... /ISSUED 317 PM CST MON NOV 5 2012/
SYNOPSIS...ANALYSIS OF THE 19Z MSL DATA SHOWED A FRONTAL WAVE IN
SOUTHERN SASKATCHEWAN. ASSOCIATED WITH THE SURFACE LOW...WATER
VAPOR IMAGERY WAS SHOWING A POTENTIAL VORTICITY ANOMALY NEAR THE
BOUNDARY BETWEEN EAST CENTRAL ALBERTA AND WEST CENTRAL
SASKATCHEWAN. A SURFACE FRONT HAD MOVED OUT OF SOUTHERN ALBERTA
AND SASKATCHEWAN INTO NORTHERN MONTANA. THERE WAS ALSO AN
ABUNDANCE OF JETSTREAM-RELATED CIRRUS/CIRROSTRATUS STREAMING OVER
THE MONTANA-WYOMING ROCKIES ON THE NORTHWEST FLOW. VISIBLE IMAGERY
INDICATED SOME CUMULIFORM CLOUDINESS FROM CENTRAL TO SOUTHWEST
NEBRASKA.
SHORT TERM...A FRONT COMING OUT OF NORTHERN MONTANA WILL COME
THROUGH NEBRASKA LATE TONIGHT TO EARLY TUESDAY AND BRING SOME
PATCHY CLOUDINESS. THEN...RETURN FLOW WILL BRING THE FRONT BACK
TOWARD THE EAST AGAIN TUESDAY NIGHT AND...WITH IT...SOME
CLOUDINESS. TEMPERATURES TONIGHT WILL BE HELD TO THE MID TO UPPER
30S TONIGHT BY THE AREAS OF CLOUDINESS. WITH MORE SUNSHINE THAN
TODAY AND BREEZIER CONDITIONS...TEMPERATURES TUESDAY WILL BE
SOMEWHAT WARMER THAN TODAY. CLEARING SKY AND LIGHT WIND WILL LET
TEMPERATURES FALL INTO THE 20S OVER THE AREA TUESDAY NIGHT.
LONG TERM...A SIGNIFICANT LONG WAVE TROUGH IS STILL PROGGED TO
PROGRESS EAST ACROSS THE THE PLAINS SATURDAY INTO SUNDAY. AHEAD
OF THIS FEATURE...MILD WEATHER WILL CONTINUE...WITH HIGHS ABOVE
NORMAL WEDNESDAY THROUGH FRIDAY. A DRASTIC CHANGE IN THE WEATHER
WILL OCCUR SATURDAY...AS A STRONG COLD FRONT PLOWS SOUTHEAST
ACROSS NEBRASKA. GUSTY NORTHWEST WINDS AND FALLING TEMPERATURES
CAN BE EXPECTED BEHIND THE FRONT SATURDAY AFTERNOON...WITH LIGHT
RAIN OR LIGHT SNOW DEVELOPING WITHIN AREA OF STRONG FRONTOGENESIS
BEHIND THE FRONT. LIGHT SNOW WILL LINGER INTO SATURDAY NIGHT...AND
SHOULD END BY SUNDAY MORNING AS HIGH PRESSURE BEGINS TO BUILD INTO
THE AREA. IT IS STILL TOO EARLY TO KNOW EXACTLY HOW MUCH SNOW WILL
ACCUMULATE...BUT ALL INDICATIONS ARE THAT AMOUNTS SHOULD BE
LIGHT...WITH PERHAPS AN INCH OR TWO FALLING ACROSS NORTHWEST
NEBRASKA. WILL CONTINUE TO MONITOR...AND UPDATE FORECASTS AS THE
STORM SYSTEM GETS CLOSER. VERY CHILLY CONDITIONS ARE EXPECTED
SUNDAY...WITH MANY AREAS STRUGGLING TO REACH THE FREEZING MARK.
SOME TEMPERATURE RECOVERY IS EXPECTED MONDAY AS THE COLDEST AIR
MOVES EAST OF THE AREA.
AVIATION... NO SIGNIFICANT RESTRICTIVE WEATHER IS EXPECTED TONIGHT
THROUGH TUESDAY. CEILINGS...IF ANY...WILL BE AT OR ABOVE 5000
FEET AGL. WIND IS EXPECTED TO INCREASE TUESDAY. IN NORTH CENTRAL
NEBRASKA...NEAR ONL...BUB...BBW AND ANW...THE WIND IS EXPECTED TO
BE 310-330 INCREASING TO 20-23G26-30 BY 18Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM/EXTENDED...MASEK
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
633 PM CST MON NOV 5 2012
.DISCUSSION...
TWEAKED THE FORECAST JUST SLIGHTLY TO BRING PRECIP CHANCES INTO
NORTHEAST NEBRASKA A FEW HOURS EARLIER...BASED ON RADAR ECHOS
MOVING OUT OF SOUTH DAKOTA AND NORTH CENTRAL NEBRASKA. ALSO
TRIMMED THE BACK EDGE OF THE PRECIP JUST A BIT...AND BROUGHT IT
JUST A LITTLE BIT FURTHER SOUTH. EITHER WAY...IT WILL LIKELY BE
VERY VERY LIGHT...PERHAPS ONLY JUST TRACE AMOUNTS.
ALSO TWEAKED THE WINDS UP A COUPLE OF KNOTS ON TUESDAY IN
NORTHEAST NEBRASKA. WINDS MAY BE JUST SHY OF WIND ADVISORY
CRITERIA IN NORTHEAST NEBRASKA AROUND 30 MPH SUSTAINED.
DEWALD
&&
.PREV DISCUSSION... /ISSUED 524 PM CST MON NOV 5 2012/
AVIATION...06Z TAFS FOR KOMA...KLNK AND KOFK. LIFR CONDITIONS
WILL PERSIST AT KOMA...AND JUST WHEN THESE LOW CLOUDS BREAK IS THE
BIG QUESTION. BELIEVE IT MAY TAKE SEVERAL MORE HOURS UNTIL PERHAPS
09Z/10Z. MVFR CONDITIONS AT KLNK/KOFK EARLY IN THE PERIOD...BUT
THESE CLOUDS SHOULD SCATTER OUT MUCH QUICKER BY 01/02Z.
MEANWHILE...HIGH CLOUDS STREAMING OVER THE FORECAST AHEAD OF A
COLD FRONT...THAT SHOULD ARRIVE AT KOFK BY 12Z...AND KLNK/KOMA BY
14Z. COULD BE A SPRINKLE OR TWO AT KOFK DURING THE OVERNIGHT
HOURS...BUT NOT SIGNIFICANT ENOUGH TO ADD TO THE TAF JUST YET.
LIGHT SOUTHERLY WINDS AHEAD OF THE FRONT...BECOMING SOUTHWEST...AND
THEN EVENTUALLY NORTHWEST ONCE THE FRONT MOVES THROUGH. BEHIND THE
FRONT...WINDS WILL LIKELY INCREASE TO SUSTAINED 20KTS...WITH GUSTS
UP TO 30KTS BY 14/16Z.
DEWALD
PREV DISCUSSION... /ISSUED 318 PM CST MON NOV 5 2012/
SHORT TERM...TONIGHT THROUGH THURSDAY.
MAIN FORECAST CONCERN IS SMALL CHANCE FOR SHOWERS IN OUR
NORTHEAST OVERNIGHT.
LATEST WATER VAPOR IMAGERY AND RAP 500MB ANALYSIS SHOW THE REGION IN
NORTHWESTERLY FLOW ALOFT WITH SHORTWAVE ENERGY QUICKLY DROPPING
THROUGH THE SOUTHERN CANADIAN PRAIRIE PROVINCES. ASSOCIATED SFC LOW
PRESSURE AREA CONTINUES TO QUICKLY MOVE SOUTHEAST AHEAD OF THIS
UPPER FEATURE WITH WIDESPREAD SHOWERS ACROSS NORTH DAKOTA. THESE
FEATURES WILL CONTINUE THEIR SOUTHWARD PROGRESSION AND SHOULD BRUSH
THE NORTHEASTERN COUNTIES OVERNIGHT...MAINLY AFTER 06Z. HAVE ADDED A
SMALL CHANCE FOR SHOWERS AS MOISTURE PROFILES ARE SLOW TO SATURATE
LOWER LEVELS. IN ADDITION...ASSOCIATED SFC COLD FRONT WILL PUSH
THROUGH THE FORECAST AREA TUESDAY MORNING. GOOD MOMENTUM TRANSFER
SHOULD ALLOW GUSTY CONDITIONS INTO TUESDAY AFTERNOON BEHIND THE
FRONT. HIGH TEMPERATURES SHOULD ONLY TOP OUT IN THE LOWER 50S
ACROSS THE NORTHEASTERN CWA WITH UPPER 50S IN THE SOUTHWEST. SFC
HIGH PRESSURE QUICKLY BUILDS IN WEDNESDAY MORNING BRINGING CLEAR
AND CALM CONDITIONS. A GRADUAL WARMING TREND WEDNESDAY INTO
THURSDAY IS EXPECTED AS A WESTERN RIDGE BUILDS EAST OVER THE AREA
AND RETURN FLOW DEVELOPS AROUND SFC HIGH PRESSURE.
KERN
LONG TERM...THURSDAY NIGHT THROUGH MONDAY.
LOOKS LIKE SOME ACTIVE WEATHER FOR THE WEEKEND WITH BIG SWINGS IN
TEMPERATURES.
THE EC/GFS/GEFS/CANADIAN ARE ALL IN FAIRLY GOOD AGREEMENT...WITH
SOME TYPICALLY TIMING AND STRENGTH DIFFERENCES. THE FORECAST AREA
WILL BE IN THE WARM SECTOR THURSDAY NIGHT WITH AN INVERTED TROF
SETTLING INTO NORTHEAST NEBRASKA. THE GULF IS OPEN WITH H85 FLOW
FROM TEXAS THROUGH THE PLAINS WITH THE DRY SLOT HEADING ACROSS NORTH
CENTRAL KANSAS BY 12Z FRIDAY. THE SURFACE LOW INITIALLY OVER THE
CENTRAL ROCKIES TRACKS NORTHEAST ALONG THE FRONT AND BY 18Z SATURDAY
IS CENTERED SOMEWHERE BETWEEN EASTERN SOUTH DAKOTA/EASTERN NEBRASKA
(GFS/EC/GEFS) OR MINNESOTA (CANADIAN). THE BULK OF THE
PRECIPITATION WILL INITIALLY BE AHEAD OF...NORTH...AND TO THE WEST
OF THE FORECAST AREA. SATURDAY NIGHT LOOKS TO BE THE BEST CHANCE
FOR PRECIPITATION...ALTHOUGH THERE WILL BE LIFT/WAA DURING THE DAY
SATURDAY. THE GFS HAS A SURGE OF HIGHER DEWPOINTS NEAR THE MISSOURI
RIVER AND THEN LIFTING NORTH AND SHIFTING QUICKLY EAST. THE EC IS
SLOWER WITH THE DEEP MOISTURE AND HOLDS ON TO THE HIGH 10 TO 12DEG C
H85 DEWPOINTS. COMBINED WITH THE LIFT WITH THIS DYNAMIC SYSTEM THESE
DIFFERENCES ACCOUNT FOR THE DIFFERENCES IN RESULTANT QPF WITH HIGHER
PRECIPITATION AMOUNTS WITH THE EC.
TEMPERATURES FRIDAY AND SATURDAY WILL BE IN THE 60S AND 70S AND
MUCH COLDER FOR SUNDAY AND MONDAY WITH HIGHS IN THE 30S AND 40S.
FOR NOW HAVE SOME CHANCE POPS SATURDAY AFTERNOON AND LIKELY POPS
SATURDAY NIGHT AND DEPENDING ON IF THE SYSTEM SLOWS DOWN...SOME POPS
INTO SUNDAY. WITH INSTABILITY AHEAD OF THE FRONT WILL INCLUDE
THUNDER. THERE COULD BE A MIX IN THE NORTHEAST AS COLDER AIR WORKS
INTO THE SYSTEM IN NORTHEAST NEBRASKA. SHOULD THERE BE LINGERING
PRECIPITATION SUNDAY...THERE COULD BE A MIX OR MINOR
ACCUMULATIONS SUNDAY.
ZAPOTOCNY
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
547 PM CST MON NOV 5 2012
.UPDATE...
.AVIATION...
VFR IS EXPECTED MOST AREAS TONIGHT AND TUESDAY.
A COLD FRONT WILL MOVE THROUGH TONIGHT WITH WINDS INCREASING AFTER
15Z TO 32025G35KT ACROSS NCNTL NEB EAST OF HIGHWAY 83.
SPRINKLES HAVE DEVELOPED AHEAD OF THE FRONT THIS EVENING. VFR IS
EXPECTED BENEATH THOSE RADAR RETURNS. ALSO...THE BANK OF MVFR CIGS
ACROSS NCNTL NEB GETS SHOVED EAST AS THE COLD FRONT APPROACHES
LATE TONIGHT...09Z- 12Z. NOTE THE RUC SUGGESTS SOME POTENTIAL FOR
MVFR CIGS LATE TONIGHT WITH THE COLD FRONT. FOR NOW PLAN ON VFR.
BEST GUESS ON MVFR CAN BE MADE AS THE FRONT GETS CLOSER THIS
EVENING.
&&
.PREV DISCUSSION... /ISSUED 317 PM CST MON NOV 5 2012/
SYNOPSIS...ANALYSIS OF THE 19Z MSL DATA SHOWED A FRONTAL WAVE IN
SOUTHERN SASKATCHEWAN. ASSOCIATED WITH THE SURFACE LOW...WATER
VAPOR IMAGERY WAS SHOWING A POTENTIAL VORTICITY ANOMALY NEAR THE
BOUNDARY BETWEEN EAST CENTRAL ALBERTA AND WEST CENTRAL
SASKATCHEWAN. A SURFACE FRONT HAD MOVED OUT OF SOUTHERN ALBERTA
AND SASKATCHEWAN INTO NORTHERN MONTANA. THERE WAS ALSO AN
ABUNDANCE OF JETSTREAM-RELATED CIRRUS/CIRROSTRATUS STREAMING OVER
THE MONTANA-WYOMING ROCKIES ON THE NORTHWEST FLOW. VISIBLE IMAGERY
INDICATED SOME CUMULIFORM CLOUDINESS FROM CENTRAL TO SOUTHWEST
NEBRASKA.
SHORT TERM...A FRONT COMING OUT OF NORTHERN MONTANA WILL COME
THROUGH NEBRASKA LATE TONIGHT TO EARLY TUESDAY AND BRING SOME
PATCHY CLOUDINESS. THEN...RETURN FLOW WILL BRING THE FRONT BACK
TOWARD THE EAST AGAIN TUESDAY NIGHT AND...WITH IT...SOME
CLOUDINESS. TEMPERATURES TONIGHT WILL BE HELD TO THE MID TO UPPER
30S TONIGHT BY THE AREAS OF CLOUDINESS. WITH MORE SUNSHINE THAN
TODAY AND BREEZIER CONDITIONS...TEMPERATURES TUESDAY WILL BE
SOMEWHAT WARMER THAN TODAY. CLEARING SKY AND LIGHT WIND WILL LET
TEMPERATURES FALL INTO THE 20S OVER THE AREA TUESDAY NIGHT.
LONG TERM...A SIGNIFICANT LONG WAVE TROUGH IS STILL PROGGED TO
PROGRESS EAST ACROSS THE THE PLAINS SATURDAY INTO SUNDAY. AHEAD
OF THIS FEATURE...MILD WEATHER WILL CONTINUE...WITH HIGHS ABOVE
NORMAL WEDNESDAY THROUGH FRIDAY. A DRASTIC CHANGE IN THE WEATHER
WILL OCCUR SATURDAY...AS A STRONG COLD FRONT PLOWS SOUTHEAST
ACROSS NEBRASKA. GUSTY NORTHWEST WINDS AND FALLING TEMPERATURES
CAN BE EXPECTED BEHIND THE FRONT SATURDAY AFTERNOON...WITH LIGHT
RAIN OR LIGHT SNOW DEVELOPING WITHIN AREA OF STRONG FRONTOGENESIS
BEHIND THE FRONT. LIGHT SNOW WILL LINGER INTO SATURDAY NIGHT...AND
SHOULD END BY SUNDAY MORNING AS HIGH PRESSURE BEGINS TO BUILD INTO
THE AREA. IT IS STILL TOO EARLY TO KNOW EXACTLY HOW MUCH SNOW WILL
ACCUMULATE...BUT ALL INDICATIONS ARE THAT AMOUNTS SHOULD BE
LIGHT...WITH PERHAPS AN INCH OR TWO FALLING ACROSS NORTHWEST
NEBRASKA. WILL CONTINUE TO MONITOR...AND UPDATE FORECASTS AS THE
STORM SYSTEM GETS CLOSER. VERY CHILLY CONDITIONS ARE EXPECTED
SUNDAY...WITH MANY AREAS STRUGGLING TO REACH THE FREEZING MARK.
SOME TEMPERATURE RECOVERY IS EXPECTED MONDAY AS THE COLDEST AIR
MOVES EAST OF THE AREA.
AVIATION... NO SIGNIFICANT RESTRICTIVE WEATHER IS EXPECTED TONIGHT
THROUGH TUESDAY. CEILINGS...IF ANY...WILL BE AT OR ABOVE 5000
FEET AGL. WIND IS EXPECTED TO INCREASE TUESDAY. IN NORTH CENTRAL
NEBRASKA...NEAR ONL...BUB...BBW AND ANW...THE WIND IS EXPECTED TO
BE 310-330 INCREASING TO 20-23G26-30 BY 18Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM/EXTENDED...CDC
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
524 PM CST MON NOV 5 2012
.AVIATION...06Z TAFS FOR KOMA...KLNK AND KOFK. LIFR CONDITIONS
WILL PERSIST AT KOMA...AND JUST WHEN THESE LOW CLOUDS BREAK IS THE
BIG QUESTION. BELIEVE IT MAY TAKE SEVERAL MORE HOURS UNTIL PERHAPS
09Z/10Z. MVFR CONDITIONS AT KLNK/KOFK EARLY IN THE PERIOD...BUT
THESE CLOUDS SHOULD SCATTER OUT MUCH QUICKER BY 01/02Z.
MEANWHILE...HIGH CLOUDS STREAMING OVER THE FORECAST AHEAD OF A
COLD FRONT...THAT SHOULD ARRIVE AT KOFK BY 12Z...AND KLNK/KOMA BY
14Z. COULD BE A SPRINKLE OR TWO AT KOFK DURING THE OVERNIGHT
HOURS...BUT NOT SIGNIFICANT ENOUGH TO ADD TO THE TAF JUST YET.
LIGHT SOUTHERLY WINDS AHEAD OF THE FRONT...BECOMING SOUTHWEST...AND
THEN EVENTUALLY NORTHWEST ONCE THE FRONT MOVES THROUGH. BEHIND THE
FRONT...WINDS WILL LIKELY INCREASE TO SUSTAINED 20KTS...WITH GUSTS
UP TO 30KTS BY 14/16Z.
DEWALD
&&
.PREV DISCUSSION... /ISSUED 318 PM CST MON NOV 5 2012/
SHORT TERM...TONIGHT THROUGH THURSDAY.
MAIN FORECAST CONCERN IS SMALL CHANCE FOR SHOWERS IN OUR
NORTHEAST OVERNIGHT.
LATEST WATER VAPOR IMAGERY AND RAP 500MB ANALYSIS SHOW THE REGION IN
NORTHWESTERLY FLOW ALOFT WITH SHORTWAVE ENERGY QUICKLY DROPPING
THROUGH THE SOUTHERN CANADIAN PRAIRIE PROVINCES. ASSOCIATED SFC LOW
PRESSURE AREA CONTINUES TO QUICKLY MOVE SOUTHEAST AHEAD OF THIS
UPPER FEATURE WITH WIDESPREAD SHOWERS ACROSS NORTH DAKOTA. THESE
FEATURES WILL CONTINUE THEIR SOUTHWARD PROGRESSION AND SHOULD BRUSH
THE NORTHEASTERN COUNTIES OVERNIGHT...MAINLY AFTER 06Z. HAVE ADDED A
SMALL CHANCE FOR SHOWERS AS MOISTURE PROFILES ARE SLOW TO SATURATE
LOWER LEVELS. IN ADDITION...ASSOCIATED SFC COLD FRONT WILL PUSH
THROUGH THE FORECAST AREA TUESDAY MORNING. GOOD MOMENTUM TRANSFER
SHOULD ALLOW GUSTY CONDITIONS INTO TUESDAY AFTERNOON BEHIND THE
FRONT. HIGH TEMPERATURES SHOULD ONLY TOP OUT IN THE LOWER 50S
ACROSS THE NORTHEASTERN CWA WITH UPPER 50S IN THE SOUTHWEST. SFC
HIGH PRESSURE QUICKLY BUILDS IN WEDNESDAY MORNING BRINGING CLEAR
AND CALM CONDITIONS. A GRADUAL WARMING TREND WEDNESDAY INTO
THURSDAY IS EXPECTED AS A WESTERN RIDGE BUILDS EAST OVER THE AREA
AND RETURN FLOW DEVELOPS AROUND SFC HIGH PRESSURE.
KERN
LONG TERM...THURSDAY NIGHT THROUGH MONDAY.
LOOKS LIKE SOME ACTIVE WEATHER FOR THE WEEKEND WITH BIG SWINGS IN
TEMPERATURES.
THE EC/GFS/GEFS/CANADIAN ARE ALL IN FAIRLY GOOD AGREEMENT...WITH
SOME TYPICALLY TIMING AND STRENGTH DIFFERENCES. THE FORECAST AREA
WILL BE IN THE WARM SECTOR THURSDAY NIGHT WITH AN INVERTED TROF
SETTLING INTO NORTHEAST NEBRASKA. THE GULF IS OPEN WITH H85 FLOW
FROM TEXAS THROUGH THE PLAINS WITH THE DRY SLOT HEADING ACROSS NORTH
CENTRAL KANSAS BY 12Z FRIDAY. THE SURFACE LOW INITIALLY OVER THE
CENTRAL ROCKIES TRACKS NORTHEAST ALONG THE FRONT AND BY 18Z SATURDAY
IS CENTERED SOMEWHERE BETWEEN EASTERN SOUTH DAKOTA/EASTERN NEBRASKA
(GFS/EC/GEFS) OR MINNESOTA (CANADIAN). THE BULK OF THE
PRECIPITATION WILL INITIALLY BE AHEAD OF...NORTH...AND TO THE WEST
OF THE FORECAST AREA. SATURDAY NIGHT LOOKS TO BE THE BEST CHANCE
FOR PRECIPITATION...ALTHOUGH THERE WILL BE LIFT/WAA DURING THE DAY
SATURDAY. THE GFS HAS A SURGE OF HIGHER DEWPOINTS NEAR THE MISSOURI
RIVER AND THEN LIFTING NORTH AND SHIFTING QUICKLY EAST. THE EC IS
SLOWER WITH THE DEEP MOISTURE AND HOLDS ON TO THE HIGH 10 TO 12DEG C
H85 DEWPOINTS. COMBINED WITH THE LIFT WITH THIS DYNAMIC SYSTEM THESE
DIFFERENCES ACCOUNT FOR THE DIFFERENCES IN RESULTANT QPF WITH HIGHER
PRECIPITATION AMOUNTS WITH THE EC.
TEMPERATURES FRIDAY AND SATURDAY WILL BE IN THE 60S AND 70S AND
MUCH COLDER FOR SUNDAY AND MONDAY WITH HIGHS IN THE 30S AND 40S.
FOR NOW HAVE SOME CHANCE POPS SATURDAY AFTERNOON AND LIKELY POPS
SATURDAY NIGHT AND DEPENDING ON IF THE SYSTEM SLOWS DOWN...SOME POPS
INTO SUNDAY. WITH INSTABILITY AHEAD OF THE FRONT WILL INCLUDE
THUNDER. THERE COULD BE A MIX IN THE NORTHEAST AS COLDER AIR WORKS
INTO THE SYSTEM IN NORTHEAST NEBRASKA. SHOULD THERE BE LINGERING
PRECIPITATION SUNDAY...THERE COULD BE A MIX OR MINOR
ACCUMULATIONS SUNDAY.
ZAPOTOCNY
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
350 PM EST SUN NOV 4 2012
.SYNOPSIS...
HIGH PRESSURE ON MONDAY WILL GIVE WAY TO A DEVELOPING COASTAL STORM
MONDAY NIGHT AND TUESDAY. THIS NOREASTER WILL TRACK UP THE EAST
COAST IN MID WEEK AS HIGH PRESSURE PREVAILS OVER OUR REGION FOR THE
REST OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
SMALL AREA OF SHRA COINCIDENT WITH THE COLD FRONT ENTERING THE CWFA
ATTM. RAP AND HRRR TAKE THIS AREA ACROSS NE GA AND THE UPSTATE AND
EAST OF THE CWFA BY ABOUT 01Z. THIS LOOKS REASONABLE GIVEN CURRENT
CONDITIONS. EXPECT ONLY A FEW HUNDREDTHS OF QPF AT MOST WITH THESE
SHRA. SKIES SHUD CLEAR BEHIND THE PRECIP AS DRIER AIR WORKS IN
BEHIND THE FRONT. A COOL AIR MASS MOVES IN AS WELL...BUT THE
PRESSURE GRADIENT DOES NOT RELAX UNTIL NEARLY DAYBREAK AS HIGH
PRESSURE BUILDS IN OVERNIGHT. STILL...EXPECT TEMPS A FEW DEGREES
BELOW NORMAL...SO WITH CLEARING SKIES AND LIGHT WINDS...PATCHY FROST
WILL DEVELOP ACROSS THE I-40 CORRIDOR.
HIGH PRESSURE CONTINUES TO BUILD INTO THE AREA FROM THE NORTH ON
MONDAY. THE BULK OF THE DAY SHUD BE MOSTLY SUNNY...BUT CLOUDS WILL
INCREASE ACROSS THE WRN CWFA LATE IN THE DAY AHEAD OF THE NEXT WX
SYSTEM. AFTER A INCREASE IN N TO NELY WINDS WITH MIXING...WINDS
BECOME LIGHT FOR THE AFTERNOON. HIGHS WILL BE 5 TO 10 DEGREES BELOW
NORMAL.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AS OF 215 PM SUNDAY...MODELS ARE IN GOOD AGREEMENT WITH THE
DEEP-DIGGING SHORTWAVE MONDAY NIGHT AND TUESDAY...TRENDING FURTHER
SOUTH WITH THE SYSTEM AND KEEPING IT FAIRLY COMPACT AS IT ENTERS THE
CAROLINA COASTAL WATERS. TAKING A BLEND...POPS WERE CUT BACK...ESP
IN THE NORTHERN ZONES. TEMPS ARE TRICKY...AS MODEST SFC HIGH PRES
WILL WEDGE DOWN THE EASTERN SIDE OF THE APPALACHIANS. GUIDANCE HAS
TRENDED WARMER...PROBABLY DUE TO LTL IF ANY PRECIP DURING THE DAY ON
TUESDAY. ONLY TWEAKED THE TEMPS FOR BOTH MONDAY NIGHT AND TUESDAY.
THE 00Z ECMWF STILL HAS THE MOST QPF ALONG THE SOUTHERN FRINGE OF
THE CWFA...THANKS TO A BAND OF MID LVL FRONTOGENESIS. A VERY TIGHT
GRADIENT OF POPS IS LIKELY ON THE NORTH SIDE OF THIS SYSTEM...MAKING
FOR A BELOW AVERAGE CONFIDENCE FCST FOR THE CHARLOTTE AREA. IN ANY
CASE...IT WILL BE COOL...WITH TEMPS ABOUT 10-15 DEG BELOW NORMAL.
TUESDAY NIGHT AND WEDNESDAY...A NORTHERN STREAM SHORTWAVE WILL DIVE
SE INTO THE OHIO VALLEY AND CROSS THE CWFA BY MIDDAY WEDNESDAY.
MODELS HAVE TRENDED A LITTLE WETTER WITH THIS FEATURE...BRINGING
LLVL FLOW AROUND TO NW AND INCREASING DURING THE DAY. THE BEST
UPSLOPE DOES NOT LINE UP WITH THE MID-UPR QG FORCING HOWEVER. SO
WILL GO WITH A CHC POP ALONG THE TN LINE DURING THESE PERIODS. ONLY
LIGHT SNOW ACCUM EXPECTED IN THE HIGHEST ELEVATIONS ALONG THE TN
LINE. OTHERWISE...DOWNSLOPE AND SUBSIDENCE BEHIND THE MAIN LOW PRES
SYSTEM THAT WILL BE LIFTING NE ALONG THE EASTERN SEABOARD.
THICKNESSES REMAIN LOW...SUCH THAT THE MOS GUIDANCE SEEMS TOO WARM.
WILL UNDERCUT MOS SLIGHTLY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 200 PM SUNDAY...THE LATEST MEDIUM RANGE MODELS CONTINUE TO
INDICATE THAT A PERIOD OF NW FLOW PRECIP OVER THE NC
MOUNTAINS/VALLEYS WILL CONTINUE THROUGH WEDNESDAY EVENING AS AN
ADDITIONAL UPPER ENERGY AND MOISTURE ROTATES IN BEHIND THE DEPARTING
LOW PRESSURE. EXPECT MAINLY RAIN SHOWERS WITH SOME SNOW POSSIBLE IN
THE HIGHER ELEVATIONS ALONG THE NC/TN BORDER AFTER SUNSET.
WEDNESDAY NIGHT THROUGH SUNDAY...BOTH THE LATEST GFS AND ECMWF
MODELS ARE IN GOOD AGREEMENT ON CANADIAN HIGH PRESSURE BUILDING IN
BEHIND THE EAST COAST STORM BY WED NIGHT AND LINGER INTO EARLY NEXT
WEEK. THIS WILL RESULT IN CLEAR SKIES WITH TEMPERATURES GRADUALLY
WARMING BACK TO NORMAL BY END OF THE WEEK.
&&
.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
AT KCLT...VFR THROUGH THE PERIOD. STILL LOOKS LIKE ONLY SCT LOW VFR
CLOUDS WILL MOVE IN FOR THE AFTERNOON. HOWEVER...CANNOT COMPLETELY
RULE OUT A BRIEF CIG THIS AFTERNOON. OTHERWISE...STILL EXPECT ANY
CONVECTION TO BE WELL SOUTH OF THE AIRFIELD THIS AFTERNOON AND EARLY
EVENING WITH THE FRONT REMAINING SOUTH OF THE AIRFIELD. SYNOPTIC AND
MESOSCALE GUIDANCE ALL SHOW THIS TREND AS WELL. EXPECT NLY WIND TO
BECOME NNE THIS EVENING. THERE COULD BE SOME LOW END GUSTS FROM TIME
TO TIME...BUT TIMING REMAINS PROBLEMATIC. EXPECT CLEARING SKIES
AFTER MIDNIGHT CONTINUING THRU MON MORN. NNE WIND WILL SHOW AN
UPTICK IN SPEED BY MID MORNING AS MIXING RETURNS.
ELSEWHERE...VERY SIMILAR PROGRESSION AS WITH KCLT...BUT WIND WILL BE
FURTHER COMPLICATED OVER THE SC SITES BY MOVEMENT OF SFC LOW ALONG
THE FRONT. IN GENERAL...WINDS ACROSS NC WILL REMAIN N TO NE...WHILE
WINDS AT KAND WILL GO FROM W TO NW TO N BY EVENING. KGSP/KGMU WILL
BE LIGHT AND VARIABLE BECOMING NNE. N TO NE WIND WILL CONTINUE
OVERNIGHT AND THRU THE MORNING MONDAY. KAVL WILL SEE GUSTS INTO
EARLY EVENING. THE SC SITES COULD SEE LOW END GUSTS AS WELL. KAND
HAS THE BEST CHC OF SEEING ANY CONVECTION THIS AFTERNOON...BUT EVEN
THERE CHC IS TOO LOW FOR TAF MENTION. OTHERWISE...SCT LOW VFR AND
BKN CIRRUS WILL CLEAR OUT AFTER MIDNIGHT AND CONTINUE MON MORNING.
CANNOT RULE OUT A BRIEF LOW VFR CIG THIS AFTERNOON HOWEVER.
OUTLOOK...DRY FCST CONTINUES MONDAY AFTERNOON BEFORE ANOTHER SYSTEM
RETURNS FROM THE WEST MONDAY NIGHT AND TUESDAY. RESTRICTIONS LOOK
POSSIBLE WITH THE TUESDAY SYSTEM...WHICH COULD STRENGTHEN RAPIDLY
OFF THE SE COAST THROUGH MID WEEK.
AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...
WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...DEO
NEAR TERM...RWH
SHORT TERM...ARK
LONG TERM...JOH
AVIATION...RWH
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
240 PM EST SUN NOV 4 2012
.SYNOPSIS...
HIGH PRESSURE ON MONDAY WILL GIVE WAY TO A DEVELOPING COASTAL STORM
MONDAY NIGHT AND TUESDAY. THIS NOREASTER WILL TRACK UP THE EAST
COAST IN MID WEEK AS HIGH PRESSURE PREVAILS OVER OUR REGION FOR THE
REST OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
SMALL AREA OF SHRA COINCIDENT WITH THE COLD FRONT ENTERING THE CWFA
ATTM. RAP AND HRRR TAKE THIS AREA ACROSS NE GA AND THE UPSTATE AND
EAST OF THE CWFA BY ABOUT 01Z. THIS LOOKS REASONABLE GIVEN CURRENT
CONDITIONS. EXPECT ONLY A FEW HUNDREDTHS OF QPF AT MOST WITH THESE
SHRA. SKIES SHUD CLEAR BEHIND THE PRECIP AS DRIER AIR WORKS IN
BEHIND THE FRONT. A COOL AIR MASS MOVES IN AS WELL...BUT THE
PRESSURE GRADIENT DOES NOT RELAX UNTIL NEARLY DAYBREAK AS HIGH
PRESSURE BUILDS IN OVERNIGHT. STILL...EXPECT TEMPS A FEW DEGREES
BELOW NORMAL...SO WITH CLEARING SKIES AND LIGHT WINDS...PATCHY FROST
WILL DEVELOP ACROSS THE I-40 CORRIDOR.
HIGH PRESSURE CONTINUES TO BUILD INTO THE AREA FROM THE NORTH ON
MONDAY. THE BULK OF THE DAY SHUD BE MOSTLY SUNNY...BUT CLOUDS WILL
INCREASE ACROSS THE WRN CWFA LATE IN THE DAY AHEAD OF THE NEXT WX
SYSTEM. AFTER A INCREASE IN N TO NELY WINDS WITH MIXING...WINDS
BECOME LIGHT FOR THE AFTERNOON. HIGHS WILL BE 5 TO 10 DEGREES BELOW
NORMAL.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AS OF 215 PM SUNDAY...MODELS ARE IN GOOD AGREEMENT WITH THE
DEEP-DIGGING SHORTWAVE MONDAY NIGHT AND TUESDAY...TRENDING FURTHER
SOUTH WITH THE SYSTEM AND KEEPING IT FAIRLY COMPACT AS IT ENTERS THE
CAROLINA COASTAL WATERS. TAKING A BLEND...POPS WERE CUT BACK...ESP
IN THE NORTHERN ZONES. TEMPS ARE TRICKY...AS MODEST SFC HIGH PRES
WILL WEDGE DOWN THE EASTERN SIDE OF THE APPALACHIANS. GUIDANCE HAS
TRENDED WARMER...PROBABLY DUE TO LTL IF ANY PRECIP DURING THE DAY ON
TUESDAY. ONLY TWEAKED THE TEMPS FOR BOTH MONDAY NIGHT AND TUESDAY.
THE 00Z ECMWF STILL HAS THE MOST QPF ALONG THE SOUTHERN FRINGE OF
THE CWFA...THANKS TO A BAND OF MID LVL FRONTOGENESIS. A VERY TIGHT
GRADIENT OF POPS IS LIKELY ON THE NORTH SIDE OF THIS SYSTEM...MAKING
FOR A BELOW AVERAGE CONFIDENCE FCST FOR THE CHARLOTTE AREA. IN ANY
CASE...IT WILL BE COOL...WITH TEMPS ABOUT 10-15 DEG BELOW NORMAL.
TUESDAY NIGHT AND WEDNESDAY...A NORTHERN STREAM SHORTWAVE WILL DIVE
SE INTO THE OHIO VALLEY AND CROSS THE CWFA BY MIDDAY WEDNESDAY.
MODELS HAVE TRENDED A LITTLE WETTER WITH THIS FEATURE...BRINGING
LLVL FLOW AROUND TO NW AND INCREASING DURING THE DAY. THE BEST
UPSLOPE DOES NOT LINE UP WITH THE MID-UPR QG FORCING HOWEVER. SO
WILL GO WITH A CHC POP ALONG THE TN LINE DURING THESE PERIODS. ONLY
LIGHT SNOW ACCUM EXPECTED IN THE HIGHEST ELEVATIONS ALONG THE TN
LINE. OTHERWISE...DOWNSLOPE AND SUBSIDENCE BEHIND THE MAIN LOW PRES
SYSTEM THAT WILL BE LIFTING NE ALONG THE EASTERN SEABOARD.
THICKNESSES REMAIN LOW...SUCH THAT THE MOS GUIDANCE SEEMS TOO WARM.
WILL UNDERCUT MOS SLIGHTLY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 200 PM SUNDAY...THE LATEST MEDIUM RANGE MODELS CONTINUE TO
INDICATE THAT A PERIOD OF NW FLOW PRECIP ALONG THE NC/TN BORDER WILL
CONTINUE THROUGH WEDNESDAY EVENING AS AN ADDITIONAL UPPER ENERGY AND
MOISTURE ROTATES IN BEHIND THE DEPARTING LOW PRESSURE. THERE WILL BE
NO PRECIP TYPE ISSUE AS THE TEMPS REMAIN ABOVE FREEZING LEVEL DURING
THIS PERIOD.
WEDNESDAY NIGHT THROUGH SUNDAY...BOTH THE LATEST GFS AND ECMWF
MODELS ARE IN GOOD AGREEMENT ON CANADIAN HIGH PRESSURE BUILDING IN
BEHIND THE EAST COAST STORM BY WED NIGHT AND LINGER INTO EARLY NEXT
WEEK. THIS WILL RESULT IN CLEAR SKIES WITH TEMPERATURES GRADUALLY
WARMING BACK TO NORMAL BY END OF THE WEEK.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
AT KCLT...VFR THROUGH THE PERIOD. STILL LOOKS LIKE ONLY SCT LOW VFR
CLOUDS WILL MOVE IN FOR THE AFTERNOON. HOWEVER...CANNOT COMPLETELY
RULE OUT A BRIEF CIG THIS AFTERNOON. OTHERWISE...STILL EXPECT ANY
CONVECTION TO BE WELL SOUTH OF THE AIRFIELD THIS AFTERNOON AND EARLY
EVENING WITH THE FRONT REMAINING SOUTH OF THE AIRFIELD. SYNOPTIC AND
MESOSCALE GUIDANCE ALL SHOW THIS TREND AS WELL. EXPECT NLY WIND TO
BECOME NNE THIS EVENING. THERE COULD BE SOME LOW END GUSTS FROM TIME
TO TIME...BUT TIMING REMAINS PROBLEMATIC. EXPECT CLEARING SKIES
AFTER MIDNIGHT CONTINUING THRU MON MORN. NNE WIND WILL SHOW AN
UPTICK IN SPEED BY MID MORNING AS MIXING RETURNS.
ELSEWHERE...VERY SIMILAR PROGRESSION AS WITH KCLT...BUT WIND WILL BE
FURTHER COMPLICATED OVER THE SC SITES BY MOVEMENT OF SFC LOW ALONG
THE FRONT. IN GENERAL...WINDS ACROSS NC WILL REMAIN N TO NE...WHILE
WINDS AT KAND WILL GO FROM W TO NW TO N BY EVENING. KGSP/KGMU WILL
BE LIGHT AND VARIABLE BECOMING NNE. N TO NE WIND WILL CONTINUE
OVERNIGHT AND THRU THE MORNING MONDAY. KAVL WILL SEE GUSTS INTO
EARLY EVENING. THE SC SITES COULD SEE LOW END GUSTS AS WELL. KAND
HAS THE BEST CHC OF SEEING ANY CONVECTION THIS AFTERNOON...BUT EVEN
THERE CHC IS TOO LOW FOR TAF MENTION. OTHERWISE...SCT LOW VFR AND
BKN CIRRUS WILL CLEAR OUT AFTER MIDNIGHT AND CONTINUE MON MORNING.
CANNOT RULE OUT A BRIEF LOW VFR CIG THIS AFTERNOON HOWEVER.
OUTLOOK...DRY FCST CONTINUES MONDAY AFTERNOON BEFORE ANOTHER SYSTEM
RETURNS FROM THE WEST MONDAY NIGHT AND TUESDAY. RESTRICTIONS LOOK
POSSIBLE WITH THE TUESDAY SYSTEM...WHICH COULD STRENGTHEN RAPIDLY
OFF THE SE COAST THROUGH MID WEEK.
AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...
WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...DEO
NEAR TERM...RWH
SHORT TERM...ARK
LONG TERM...JOH
AVIATION...RWH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
929 PM CST MON NOV 5 2012
.SHORT TERM...
928 PM CST MON NOV 5 2012
GOES WATER VAPOR IMAGERY UPSTREAM OVER SOUTHERN CANADA SHOWING TWO
IMPULSES WITH A NICE SIGNAL OF DARKENING JUST WEST OF LAKE
WINNIPEG AT 02Z. THIS DARKENING WAS ASSOCIATED WITH A RAP-ANALYZED
TROPOPAUSE FOLD DOWN TO 600 MB. SOME ADDITIONAL DARKENING
ASSOCIATED WITH THE INITIAL VORTICITY ADVECTION IN THE TROUGH IN
ERN SD AS WELL. THIS LEAD TROUGH IS CAUSING SOME ELEVATED ECHO
OVER MN/SD WITH VERY LITTLE PRECIPITATION BEING OBSERVED.
THE LOCAL AREA WILL TAKE A DIRECT HIT FROM THE SECOND STRONG
SHORTWAVE TROUGH NEAR LAKE WINNIPEG BASED ON FORECAST MODEL CONSENSUS.
THIS HAS DEVELOPED A MORE N-S BAND OF ECHO ALONG THE ERN ND BORDER
EXTENDING NORTH INTO MANITOBA WITH A FEW HUNDREDTHS OF PRECIPITATION
PER HOUR BEING REPORTED. QG ANALYSIS TAKES THE LIFT FROM THESE
DYNAMICS RIGHT ACROSS THE FORECAST AREA IN THE 06.00 AND 05.18
NAM...LATEST RAP FORECASTS...AND 05.18 GFS. HAVE INCREASED
PRECIPITATION CHANCES TO 80 PERCENT IN MOST AREAS.
SOME QUESTION ON THE PRECIPITATION TYPE AS THE CLOUDS HAVE HELD
FIRM OVER SERN MN...AND SLIPPED A BIT EAST INTO NW WI.
OTHERWISE...TEMPERATURES WERE REALLY COOLING IN MOST OF EXTREME
NERN IA...SWRN AND CENTRAL WI UNDER CLEAR SKIES. ONCE THE CLOUD COMES
OVER...EVEN THOUGH IT IS 8KFT...TEMPERATURES WARM RAPIDLY 3-4F.
FOR CENTRAL WI INTO SWRN WI...WITH THICKER CLOUDS EXPECTED JUST
PRIOR TO PRECIPITATION ONSET...TEMPERATURES AND WETBULB
TEMPERATURES WOULD SEEM TO SUPPORT A BIT OF SNOW ACCUMULATION /IN
ADDITION TO I-94/NORTHEAST ACCUM AREA FROM PREV FORECAST/. WITH WARM SOILS
OF 40F OR MORE AT 2 INCHES...STILL THINK ACCUMULATION DIFFICULT.
BUT...WHERE IT IS THE COLDEST TONIGHT WILL FAVOR SOME...GENERALLY
1/2 INCH OR LESS. 06.00Z NAM SNOW DEPTH...WHICH MODELS THE LAND
SURFACE HEAT FLUXES...PLACED 0.3 INCHES OF SNOW ACCUM IN THAT
REGION...RICHLAND/ERN VERNON COUNTY/MONROE AREA.
AN OUTSIDE CHANCE OF VERY BRIEF FZRA IS POSSIBLE FOR ANY SITE
REMAINING 32F OR BELOW...AND MAINLY JUST EAST OF THE MISS RIVER
WHERE THE TOP OF THE INVERSION WOULD BE WARM ENOUGH TO MELT
INCOMING ICE. HAVE NOT ADDED THIS TO THE FORECAST BUT WE WILL
MONITOR AS IT APPROACHES LATER TONIGHT. IT MAY NEED A SPECIAL
WEATHER STATEMENT. A CHANGE TO SNOW WOULD QUICKLY RESULT AS THE
THERMAL PROFILE GOES TO THE WET-BULB NEAR 0C. FORECAST UPDATES ARE
OUT.
.LONG TERM...THURSDAY NIGHT THROUGH MONDAY
304 PM CST MON NOV 5 2012
AN ACTIVE PERIOD IS ON TAP FOR THE WEEKEND INTO EARLY NEXT WEEK AS
BROAD UPPER LEVEL TROUGHING PROPAGATES EAST ACROSS THE ROCKIES ON
INTO THE CENTRAL US AND GREAT LAKES REGION.
THE QUESTION TO START THE EXTENDED PERIOD IS WITH HOW FAR SOUTH A
COLD FRONT MAKES IT ON FRIDAY BEFORE IT STALLS OUT AND TRANSITIONS
TO A WARM FRONT. THE 05.12Z ECMWF IS TRENDING TOWARD WHAT THE GFS
HAS ADVERTISED THE PAST FEW DAYS WITH A MORE SOUTHERN SOLUTION. BY
00Z SATURDAY...THE FRONT WILL START NEAR A SURFACE LOW IN EASTERN
COLORADO AND RUN EAST THROUGH NORTHWEST IOWA AND CENTRAL
WISCONSIN. THE 05.12Z GFS SHOWS SOME PRECIPITATION DEVELOPING
ALONG THIS FRONT FRIDAY NIGHT AS THE LOW LEVEL JET KICKS IN AND
NOSES UP INTO THE REGION WHILE THE 05.12Z ECMWF/GEM KEEP IT DRY
WITH THE FOCUS A BIT FURTHER NORTH. A LOW PRESSURE SYSTEM WILL
THEN DEVELOP IN THE LEE OF THE ROCKIES ALONG THIS FRONT AND TRACK
NORTHEAST ALONG THE FRONT AND DEEPEN INTO MINNESOTA ON
SATURDAY/SATURDAY NIGHT WITH THE 05.12Z GFS/ECMWF IN DECENT
AGREEMENT ON THIS SCENARIO. THIS TRACK WILL LEAD TO SATURDAY BEING
THE WARMEST DAY OF THE WEEK WITH TEMPERATURES GETTING INTO THE
60S. AS A RESULT OF THIS RELATIVELY WARM AND MOIST AIR MASS
GETTING IN...THERE APPEARS TO BE SOME WEAK INSTABILITY THAT
DEVELOPS AHEAD OF THE FRONT SO THERE COULD BE A FEW THUNDERSTORMS
THAT DEVELOP THOUGH TIMING DOES NOT LOOK FAVORABLE FOR ANYTHING
SEVERE.
THE FRONT THEN SLOWLY TRACKS TO THE EAST ON SUNDAY WITH
PRECIPITATION LIKELY FORMING ALONG AND BEHIND IT. WITH STRONG LOW
LEVEL COLD AIR ADVECTION BEHIND THE FRONT...IT APPEARS THAT
TEMPERATURES WILL BE ABLE TO COOL ENOUGH FOR THE RAIN TO
TRANSITION TO SNOW FOR A PERIOD. THEN...THERE IS THEN CONTINUED
GOOD AGREEMENT BETWEEN THE 05.12Z GFS/ECMWF FOR THE BELLY OF THE
MID LEVEL TROUGH TO BECOME NEGATIVELY TILTED ON MONDAY WITH A
DEEPENING SURFACE LOW RUNNING UP THE COLD FRONT THROUGH CHICAGO.
THERMAL PROFILES WOULD BE COLD ENOUGH FOR THE PRECIPITATION TYPE
TO BE ALL SNOW...SO THE TRENDS WITH THIS SYSTEM WILL HAVE TO BE
MONITORED SINCE THE TRACK WOULD DICTATE WHERE THE HEAVIEST SNOW
WOULD FALL. RIGHT NOW...THE 05.12Z GFS IS FASTER WITH THE SURFACE
LOW NEAR SOUTHERN LAKE MICHIGAN BY 18Z MONDAY WHILE THE 05.12Z
ECMWF GETS IT THERE AROUND 6Z TUESDAY.
&&
.AVIATION...TONIGHT AND WEDNESDAY
630 PM CST MON NOV 5 2012
HAVE NOT CHANGED A GREAT DEAL WITH THE NEW TAF ISSUANCE AT 00Z.
THE FORECAST WAS ON TARGET. THE FIRST 12 HOURS /OVERNIGHT/ WILL
SEE A BATTLE BETWEEN LOW-LEVEL SOUTHEAST DRYING FLOW OVER WI HOLDING
MVFR/IFR CLOUDS WEST OF THE TAF SITES OVER MN. MVFR CONDITIONS ARE
ABOUT 50 MILES WEST OF KRST AT 00Z...SO THIS BATTLE OF AIR MASSES
WILL CONTINUE AS A COLD FRONT APPROACHES FOR DAYBREAK. AS THE COLD
FRONT DRAWS CLOSER...CIGS WILL SLOWLY COME DOWN TO MVFR
CONDITIONS. HOWEVER...THERE WILL BE SOME IFR CONDITIONS WEST OF
KRST THAT MAY TRY TO ADVECT EAST AHEAD OF THE COLD FRONT. THUS...THE
FORECAST CIGS MAY NEED TO BE LOWERED AROUND THE 12Z TIME AT KRST.
WILL MONITOR OBSERVATIONS AND SATELLITE AND WHEN CONFIDENCE
GROWS...WILL UPDATE TAFS.
A LIGHT RAIN PERIOD TUESDAY MORNING WILL GIVE WAY TO IMPROVING
CIGS AND GUSTY CONDITIONS...ESPECIALLY AT KRST.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
304 PM CST MON NOV 5 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM...HALBACH
AVIATION...BAUMGARDT
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1155 AM CST SUN NOV 4 2012
.SHORT TERM...THROUGH TUESDAY
141 AM CST SUN NOV 4 2012
MAIN FORECAST CONCERN IS WITH THE PRECIPITATION CHANCES TONIGHT
INTO MONDAY MORNING AND AGAIN MONDAY NIGHT INTO TUESDAY.
SURFACE ANALYSIS THIS MORNING SHOWS A LARGE AREA OF HIGH PRESSURE
REMAINS ANCHORED OVER WESTERN ONTARIO WITH THE RIDGE AXIS SOUTH
INTO THE REGION.
WATER VAPOR SATELLITE THIS MORNING SHOWS AN UPPER LEVEL LOW OVER
SOUTHEAST MINNESOTA. LOCAL RADAR AND SURFACE OBS INDICATE A LITTLE
BIT OF LIGHT PRECIPITATION IS HITTING THE GROUND ACROSS THE
WESTERN SECTIONS OF THE FORECAST AREA. THIS ACTIVITY IS MOVING TO
THE SOUTHEAST AND BASED ON THE 04.03Z HRRR AND 04.00Z HI-RES ARW
AND NMM...THIS ACTIVITY SHOULD BE SOUTH OF THE FORECAST AREA BY
12Z AND AT THIS POINT...DO NOT PLAN TO INCLUDE ANY MENTION OF THIS
IN THE TODAY PORTION OF THE FORECAST.
THE NEXT SHORT WAVE TROUGH CAN BE SEEN MOVING ACROSS SOUTHERN
ALBERTA AND SASKATCHEWAN. THIS WAVE IS EXPECTED TO ADVANCE QUICKLY
INTO THE REGION ON THE FAST NORTHWEST FLOW ALOFT. AS THE WAVE
APPROACHES THE REGION...ANOTHER UPPER LEVEL LOW IS EXPECTED TO
FORM AND PASS OVER MINNESOTA INTO IOWA WITH THE BULK OF THE SHORT
WAVE TROUGH TRACKING TO THE WEST OF THE UPPER LEVEL LOW. IN
FACT...THE 04.00Z GFS SHOWS ALL OF THE PV ADVECTION IN THE 500-300
MB LAYER STAYING OVER THE MISSOURI RIVER VALLEY. THE WAVE DOES GET
CLOSE ENOUGH TO PRODUCE SOME WEAK QG CONVERGENCE IN THE 1000-500
MB LAYER FOR AREAS ALONG AND WEST OF THE MISSISSIPPI RIVER. THE
BEST ISENTROPIC UP GLIDE WILL REMAIN WELL TO THE WEST OF THE
AREA...BUT AROUND 1 TO 2 UBAR/S DOES GET INTO THE I35 CORRIDOR ON
THE 285K SURFACE. NOT EXPECTING THIS WAVE TO PRODUCE A LOT OF
PRECIPITATION FOR THE FORECAST AREA...BUT COULD SEE ANOTHER ROUND
OF VERY LIGHT RAIN SNEAK INTO THE SOUTHWEST SECTIONS OF THE
FORECAST AREA AND WILL HAVE RAIN CHANCES ALONG AND SOUTHWEST OF A
ROCHESTER TO ELKADER LINE. SOME OF THIS LIGHT RAIN COULD LINGER
INTO MONDAY MORNING BEFORE MOVING AWAY FROM THE AREA.
WITH THE NORTHWEST FLOW ALOFT...YET ANOTHER WAVE WILL QUICKLY
ADVANCE TOWARD THE REGION FOR MONDAY NIGHT AND TUESDAY. THIS WAVE
LOOKS LIKE IT WILL START OUT FARTHER NORTH COMING OUT OF CENTRAL
ALBERTA AND SASKATCHEWAN WHICH WILL TAKE IT FARTHER NORTHEAST THAN
THE PREVIOUS TWO WAVES. THE MODELS HAVE BEEN FAIRLY CONSISTENT
SHOWING THIS WAVE TRACKING RIGHT OVER THE AREA WITH THE GFS
INDICATING UP TO 16 PVU/S OF VORTICITY ADVECTION COMING ACROSS THE
NORTHERN PORTIONS OF THE FORECAST AREA LATE MONDAY NIGHT INTO
TUESDAY MORNING. THE QG RESPONSE FROM THIS WAVE IS EXPECTED TO BE
MODERATE IN STRENGTH BUT VERY DEEP EXTENDING FROM 1000 UP TO 300
MB. VERY LITTLE IF ANY FRONTOGENESIS IS EXPECTED WITH THIS SYSTEM
AND THE ISENTROPIC RESPONSE IS ONLY AROUND 2 UBAR/S ON THE 285K
SURFACE. EXPECT THAT THIS SYSTEM WILL BE ABLE TO PRODUCE SOME
PRECIPITATION LATE MONDAY NIGHT INTO TUESDAY MORNING. HAVE RAISED
THE PRECIPITATION CHANCES TO 50 PERCENT ACROSS THE FAR NORTH AND
EXTENDED THE 20 PERCENT CHANCES SOUTH TO COVER THE REMAINDER OF
THE AREA. RAISED THE CHANCES TO 60 AND 70 PERCENT ACROSS THE EAST
FOR TUESDAY MORNING WITH 30 AND 40 PERCENT CHANCES BACK ACROSS THE
WEST. LOOKING AT THE FORECAST SOUNDINGS...EXPECTING MOST OF THIS
PRECIPITATION TO FALL AS RAIN AS THE WARM AIR ADVECTION AHEAD OF
THE WAVE SHOULD WARM THE LOW LEVEL TEMPERATURES ENOUGH TO KEEP
THINGS LIQUID. HOWEVER...CAN NOT TOTALLY RULE SOME SNOW MIXING IN
SO PLAN TO HAVE A LITTLE MIX FOR A WHILE.
.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY
141 AM CST SUN NOV 4 2012
MEDIUM RANGE MODELS IN VERY GOOD AGREEMENT THIS MORNING SHOWING
THE UPPER LEVEL RIDGE OVER THE ROCKIES WILL SLIDE EAST ACROSS THE
MIDWEST BEHIND THE TUESDAY SYSTEM. THIS RIDGING IS EXPECTED TO
SLIDE EAST PAST THE REGION THURSDAY NIGHT AND FRIDAY ALLOWING
SOUTHWEST FLOW ALOFT TO DEVELOP AS AN UPPER LEVEL LOW MOVES ACROSS
THE NORTHERN ROCKIES ONTO THE HIGH PLAINS BY SATURDAY. AT THE
SURFACE...CYCLOGENESIS SHOULD TAKE PLACE IN THE LEE OF THE
ROCKIES FRIDAY NIGHT WITH THE LOW ADVANCING NORTHEAST INTO
MINNESOTA SATURDAY. STILL SIGNIFICANT DIFFERENCES ON WHERE THE
WARM FRONT DEVELOPS WITH THE SURFACE LOW. THE GFS HAS THE WARM
FRONT ALONG THE IOWA/MISSOURI BORDER AND SHOWS PRECIPITATION
DEVELOPING NORTH OF THIS ALREADY FRIDAY WHILE THE 04.00Z ECMWF
CONTINUES TO SHOW THE WARM FRONT WELL TO THE NORTH WITH ANY
PRECIPITATION ACROSS SOUTHERN CANADA. THESE DIFFERENCES THEN
CONTINUE THROUGH THE REMAINDER OF THE PERIOD WITH THE GFS BEING
MUCH WETTER WHILE THE ECMWF KEEPS THE AREA IN THE WARM SECTOR AND
DOES NOT DEVELOP ANY PRECIPITATION UNTIL FRIDAY NIGHT INTO
SATURDAY AS THE SURFACE LOW AND COLD FRONT STARTS TO APPROACH. NO
CHANGES PLANNED TO THE MODEL CONSENSUS GRIDS AT THIS POINT WHICH
FAVOR THE DRIER ECMWF SOLUTION.
&&
.AVIATION...THROUGH 18Z MONDAY
1155 AM CST SUN NOV 4 2012
CONDITIONS ARE EXPECTED TO DETERIORATE TO IFR AT KRST AROUND 03Z
TONIGHT...LOWERING TO LIFR BY 09Z IN LIGHT RAIN AND FOG. LOOK FOR
CEILINGS TO LOWER TO AROUND 900 FT BY 03Z THEN FALLING TO 200 FT BY
09Z. VISIBILITIES WILL ALSO BE REDUCED LATE TONIGHT IN FOG AT KRST WITH
VISIBILITIES FALLING TO AROUND 1/2 SM. MVFR CONDITIONS ARE
EXPECTED TO DEVELOP AT KLSE AROUND 02Z THIS EVENING.
OTHERWISE...PLAN ON VFR TO MVFR CONDITIONS AT THE TAF SITES THIS
AFTERNOON WITH BKN CUMULUS CLOUD BASES RANGING FROM 3500 FT AT
KLSE TO AROUND 1700 FT AT KRST. CLOUD BASES ARE EXPECTED TO LOWER
INTO THE MVFR CATEGORY AROUND 02Z TONIGHT AT KLSE WITH CEILINGS AT
2000FT...LOWERING TO AROUND 1500FT BY 08Z. LIFR CONDITIONS ARE
EXPECTED TO IMPROVE TO IFR AT KRST AROUND 14Z...WITH MVFR
CONDITIONS EXPECTED BY 16Z. THE LIGHT RAIN AND LOW CEILINGS ARE IN
RESPONSE TO SURFACE LOW PRESSURE DEEPENING TONIGHT OVER WESTERN
IOWA AS AN UPPER WAVE MOVES FROM THE DAKOTAS SOUTH ALONG THE
NEBRASKA/IOWA BORDER. LOW LEVEL WARM AIR ADVECTION...PRODUCING
LIGHT PRECIPITATION...AND EAST SOUTHEASTERLY UPSLOPE FLOW WILL
PRODUCE FAVORABLE CONDITIONS FOR LOW CEILINGS AND FOG AT KRST.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
141 AM CST SUN NOV 4 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM....04
AVIATION...WETENKAMP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
520 AM CST SUN NOV 4 2012
.SHORT TERM...THROUGH TUESDAY
141 AM CST SUN NOV 4 2012
MAIN FORECAST CONCERN IS WITH THE PRECIPITATION CHANCES TONIGHT
INTO MONDAY MORNING AND AGAIN MONDAY NIGHT INTO TUESDAY.
SURFACE ANALYSIS THIS MORNING SHOWS A LARGE AREA OF HIGH PRESSURE
REMAINS ANCHORED OVER WESTERN ONTARIO WITH THE RIDGE AXIS SOUTH
INTO THE REGION.
WATER VAPOR SATELLITE THIS MORNING SHOWS AN UPPER LEVEL LOW OVER
SOUTHEAST MINNESOTA. LOCAL RADAR AND SURFACE OBS INDICATE A LITTLE
BIT OF LIGHT PRECIPITATION IS HITTING THE GROUND ACROSS THE
WESTERN SECTIONS OF THE FORECAST AREA. THIS ACTIVITY IS MOVING TO
THE SOUTHEAST AND BASED ON THE 04.03Z HRRR AND 04.00Z HI-RES ARW
AND NMM...THIS ACTIVITY SHOULD BE SOUTH OF THE FORECAST AREA BY
12Z AND AT THIS POINT...DO NOT PLAN TO INCLUDE ANY MENTION OF THIS
IN THE TODAY PORTION OF THE FORECAST.
THE NEXT SHORT WAVE TROUGH CAN BE SEEN MOVING ACROSS SOUTHERN
ALBERTA AND SASKATCHEWAN. THIS WAVE IS EXPECTED TO ADVANCE QUICKLY
INTO THE REGION ON THE FAST NORTHWEST FLOW ALOFT. AS THE WAVE
APPROACHES THE REGION...ANOTHER UPPER LEVEL LOW IS EXPECTED TO
FORM AND PASS OVER MINNESOTA INTO IOWA WITH THE BULK OF THE SHORT
WAVE TROUGH TRACKING TO THE WEST OF THE UPPER LEVEL LOW. IN
FACT...THE 04.00Z GFS SHOWS ALL OF THE PV ADVECTION IN THE 500-300
MB LAYER STAYING OVER THE MISSOURI RIVER VALLEY. THE WAVE DOES GET
CLOSE ENOUGH TO PRODUCE SOME WEAK QG CONVERGENCE IN THE 1000-500
MB LAYER FOR AREAS ALONG AND WEST OF THE MISSISSIPPI RIVER. THE
BEST ISENTROPIC UP GLIDE WILL REMAIN WELL TO THE WEST OF THE
AREA...BUT AROUND 1 TO 2 UBAR/S DOES GET INTO THE I35 CORRIDOR ON
THE 285K SURFACE. NOT EXPECTING THIS WAVE TO PRODUCE A LOT OF
PRECIPITATION FOR THE FORECAST AREA...BUT COULD SEE ANOTHER ROUND
OF VERY LIGHT RAIN SNEAK INTO THE SOUTHWEST SECTIONS OF THE
FORECAST AREA AND WILL HAVE RAIN CHANCES ALONG AND SOUTHWEST OF A
ROCHESTER TO ELKADER LINE. SOME OF THIS LIGHT RAIN COULD LINGER
INTO MONDAY MORNING BEFORE MOVING AWAY FROM THE AREA.
WITH THE NORTHWEST FLOW ALOFT...YET ANOTHER WAVE WILL QUICKLY
ADVANCE TOWARD THE REGION FOR MONDAY NIGHT AND TUESDAY. THIS WAVE
LOOKS LIKE IT WILL START OUT FARTHER NORTH COMING OUT OF CENTRAL
ALBERTA AND SASKATCHEWAN WHICH WILL TAKE IT FARTHER NORTHEAST THAN
THE PREVIOUS TWO WAVES. THE MODELS HAVE BEEN FAIRLY CONSISTENT
SHOWING THIS WAVE TRACKING RIGHT OVER THE AREA WITH THE GFS
INDICATING UP TO 16 PVU/S OF VORTICITY ADVECTION COMING ACROSS THE
NORTHERN PORTIONS OF THE FORECAST AREA LATE MONDAY NIGHT INTO
TUESDAY MORNING. THE QG RESPONSE FROM THIS WAVE IS EXPECTED TO BE
MODERATE IN STRENGTH BUT VERY DEEP EXTENDING FROM 1000 UP TO 300
MB. VERY LITTLE IF ANY FRONTOGENESIS IS EXPECTED WITH THIS SYSTEM
AND THE ISENTROPIC RESPONSE IS ONLY AROUND 2 UBAR/S ON THE 285K
SURFACE. EXPECT THAT THIS SYSTEM WILL BE ABLE TO PRODUCE SOME
PRECIPITATION LATE MONDAY NIGHT INTO TUESDAY MORNING. HAVE RAISED
THE PRECIPITATION CHANCES TO 50 PERCENT ACROSS THE FAR NORTH AND
EXTENDED THE 20 PERCENT CHANCES SOUTH TO COVER THE REMAINDER OF
THE AREA. RAISED THE CHANCES TO 60 AND 70 PERCENT ACROSS THE EAST
FOR TUESDAY MORNING WITH 30 AND 40 PERCENT CHANCES BACK ACROSS THE
WEST. LOOKING AT THE FORECAST SOUNDINGS...EXPECTING MOST OF THIS
PRECIPITATION TO FALL AS RAIN AS THE WARM AIR ADVECTION AHEAD OF
THE WAVE SHOULD WARM THE LOW LEVEL TEMPERATURES ENOUGH TO KEEP
THINGS LIQUID. HOWEVER...CAN NOT TOTALLY RULE SOME SNOW MIXING IN
SO PLAN TO HAVE A LITTLE MIX FOR A WHILE.
.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY
141 AM CST SUN NOV 4 2012
MEDIUM RANGE MODELS IN VERY GOOD AGREEMENT THIS MORNING SHOWING
THE UPPER LEVEL RIDGE OVER THE ROCKIES WILL SLIDE EAST ACROSS THE
MIDWEST BEHIND THE TUESDAY SYSTEM. THIS RIDGING IS EXPECTED TO
SLIDE EAST PAST THE REGION THURSDAY NIGHT AND FRIDAY ALLOWING
SOUTHWEST FLOW ALOFT TO DEVELOP AS AN UPPER LEVEL LOW MOVES ACROSS
THE NORTHERN ROCKIES ONTO THE HIGH PLAINS BY SATURDAY. AT THE
SURFACE...CYCLOGENESIS SHOULD TAKE PLACE IN THE LEE OF THE
ROCKIES FRIDAY NIGHT WITH THE LOW ADVANCING NORTHEAST INTO
MINNESOTA SATURDAY. STILL SIGNIFICANT DIFFERENCES ON WHERE THE
WARM FRONT DEVELOPS WITH THE SURFACE LOW. THE GFS HAS THE WARM
FRONT ALONG THE IOWA/MISSOURI BORDER AND SHOWS PRECIPITATION
DEVELOPING NORTH OF THIS ALREADY FRIDAY WHILE THE 04.00Z ECMWF
CONTINUES TO SHOW THE WARM FRONT WELL TO THE NORTH WITH ANY
PRECIPITATION ACROSS SOUTHERN CANADA. THESE DIFFERENCES THEN
CONTINUE THROUGH THE REMAINDER OF THE PERIOD WITH THE GFS BEING
MUCH WETTER WHILE THE ECMWF KEEPS THE AREA IN THE WARM SECTOR AND
DOES NOT DEVELOP ANY PRECIPITATION UNTIL FRIDAY NIGHT INTO
SATURDAY AS THE SURFACE LOW AND COLD FRONT STARTS TO APPROACH. NO
CHANGES PLANNED TO THE MODEL CONSENSUS GRIDS AT THIS POINT WHICH
FAVOR THE DRIER ECMWF SOLUTION.
&&
.AVIATION...TODAY AND TONIGHT
520 AM CDT SUN NOV 4 2012
MOISTURE/CLOUDS IN THE 900MB TO ABOUT 800MB LAYER /ROUGHLY 2K-6K FT/
WILL BE PROBLEMATIC TODAY AND TONIGHT. DEEPER/LOWER OF THIS MOISTURE
RESIDES WEST OF THE TAF SITES THIS MORNING. ISOTHERMAL OR WEAK
INVERSIONS THRU ABOUT 800MB ALONG WITH WEAK FLOW IN THE SFC-700MB
LAYER AND ANOTHER SHORTWAVE TO PASS JUST WEST OF THE FCST AREA
TONIGHT...LOOK TO KEEP THIS MOISTURE OVER THE AREA TODAY AND SLOWLY
ADVECT IT EASTWARD TONIGHT. WITH SOME DIURNAL WARMING/MIXING...
MAINLY VFR CIGS EXPECTED TODAY. WITH THE ADVECTION OF THE DEEPER
MOISTURE EAST TONIGHT AND DIURNAL COOLING...CIGS LOOK TO LOWER INTO
THE 2K-3K FT RANGE BY LATER TONIGHT INTO MON MORNING.
BOUNDARY LAYER MOISTURE TRAPPING AND THE LIGHT WINDS RESULTING IN
SOME MVFR VSBYS IN BR WEST OF THE MS RIVER EARLY THIS MORNING. THIS
WILL IMPROVE WITH DIURNAL WARMING/MIXING THIS MORNING...BUT RETURN
TONIGHT AT SITES LIKE KRST WITH THE PASSING SHORTWAVE...INCREASE OF
MOISTURE AND BOUNDARY LAYER COOLING. WEAK LIFT WITH THE PASSING
SHORTWAVE AND THE DEEPER MOISTURE MAY BE ENOUGH FOR PATCHY -RA/-DZ
TO AGAIN SPREAD ACROSS SOUTHEAST MN/NORTHEAST IA LATE TONIGHT. ADDED
VCSH TO KRST AFTER 06Z FOR NOW.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
141 AM CST SUN NOV 4 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM....04
AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
141 AM CST SUN NOV 4 2012
.SHORT TERM...THROUGH TUESDAY
141 AM CST SUN NOV 4 2012
MAIN FORECAST CONCERN IS WITH THE PRECIPITATION CHANCES TONIGHT
INTO MONDAY MORNING AND AGAIN MONDAY NIGHT INTO TUESDAY.
SURFACE ANALYSIS THIS MORNING SHOWS A LARGE AREA OF HIGH PRESSURE
REMAINS ANCHORED OVER WESTERN ONTARIO WITH THE RIDGE AXIS SOUTH
INTO THE REGION.
WATER VAPOR SATELLITE THIS MORNING SHOWS AN UPPER LEVEL LOW OVER
SOUTHEAST MINNESOTA. LOCAL RADAR AND SURFACE OBS INDICATE A LITTLE
BIT OF LIGHT PRECIPITATION IS HITTING THE GROUND ACROSS THE
WESTERN SECTIONS OF THE FORECAST AREA. THIS ACTIVITY IS MOVING TO
THE SOUTHEAST AND BASED ON THE 04.03Z HRRR AND 04.00Z HI-RES ARW
AND NMM...THIS ACTIVITY SHOULD BE SOUTH OF THE FORECAST AREA BY
12Z AND AT THIS POINT...DO NOT PLAN TO INCLUDE ANY MENTION OF THIS
IN THE TODAY PORTION OF THE FORECAST.
THE NEXT SHORT WAVE TROUGH CAN BE SEEN MOVING ACROSS SOUTHERN
ALBERTA AND SASKATCHEWAN. THIS WAVE IS EXPECTED TO ADVANCE QUICKLY
INTO THE REGION ON THE FAST NORTHWEST FLOW ALOFT. AS THE WAVE
APPROACHES THE REGION...ANOTHER UPPER LEVEL LOW IS EXPECTED TO
FORM AND PASS OVER MINNESOTA INTO IOWA WITH THE BULK OF THE SHORT
WAVE TROUGH TRACKING TO THE WEST OF THE UPPER LEVEL LOW. IN
FACT...THE 04.00Z GFS SHOWS ALL OF THE PV ADVECTION IN THE 500-300
MB LAYER STAYING OVER THE MISSOURI RIVER VALLEY. THE WAVE DOES GET
CLOSE ENOUGH TO PRODUCE SOME WEAK QG CONVERGENCE IN THE 1000-500
MB LAYER FOR AREAS ALONG AND WEST OF THE MISSISSIPPI RIVER. THE
BEST ISENTROPIC UP GLIDE WILL REMAIN WELL TO THE WEST OF THE
AREA...BUT AROUND 1 TO 2 UBAR/S DOES GET INTO THE I35 CORRIDOR ON
THE 285K SURFACE. NOT EXPECTING THIS WAVE TO PRODUCE A LOT OF
PRECIPITATION FOR THE FORECAST AREA...BUT COULD SEE ANOTHER ROUND
OF VERY LIGHT RAIN SNEAK INTO THE SOUTHWEST SECTIONS OF THE
FORECAST AREA AND WILL HAVE RAIN CHANCES ALONG AND SOUTHWEST OF A
ROCHESTER TO ELKADER LINE. SOME OF THIS LIGHT RAIN COULD LINGER
INTO MONDAY MORNING BEFORE MOVING AWAY FROM THE AREA.
WITH THE NORTHWEST FLOW ALOFT...YET ANOTHER WAVE WILL QUICKLY
ADVANCE TOWARD THE REGION FOR MONDAY NIGHT AND TUESDAY. THIS WAVE
LOOKS LIKE IT WILL START OUT FARTHER NORTH COMING OUT OF CENTRAL
ALBERTA AND SASKATCHEWAN WHICH WILL TAKE IT FARTHER NORTHEAST THAN
THE PREVIOUS TWO WAVES. THE MODELS HAVE BEEN FAIRLY CONSISTENT
SHOWING THIS WAVE TRACKING RIGHT OVER THE AREA WITH THE GFS
INDICATING UP TO 16 PVU/S OF VORTICITY ADVECTION COMING ACROSS THE
NORTHERN PORTIONS OF THE FORECAST AREA LATE MONDAY NIGHT INTO
TUESDAY MORNING. THE QG RESPONSE FROM THIS WAVE IS EXPECTED TO BE
MODERATE IN STRENGTH BUT VERY DEEP EXTENDING FROM 1000 UP TO 300
MB. VERY LITTLE IF ANY FRONTOGENESIS IS EXPECTED WITH THIS SYSTEM
AND THE ISENTROPIC RESPONSE IS ONLY AROUND 2 UBAR/S ON THE 285K
SURFACE. EXPECT THAT THIS SYSTEM WILL BE ABLE TO PRODUCE SOME
PRECIPITATION LATE MONDAY NIGHT INTO TUESDAY MORNING. HAVE RAISED
THE PRECIPITATION CHANCES TO 50 PERCENT ACROSS THE FAR NORTH AND
EXTENDED THE 20 PERCENT CHANCES SOUTH TO COVER THE REMAINDER OF
THE AREA. RAISED THE CHANCES TO 60 AND 70 PERCENT ACROSS THE EAST
FOR TUESDAY MORNING WITH 30 AND 40 PERCENT CHANCES BACK ACROSS THE
WEST. LOOKING AT THE FORECAST SOUNDINGS...EXPECTING MOST OF THIS
PRECIPITATION TO FALL AS RAIN AS THE WARM AIR ADVECTION AHEAD OF
THE WAVE SHOULD WARM THE LOW LEVEL TEMPERATURES ENOUGH TO KEEP
THINGS LIQUID. HOWEVER...CAN NOT TOTALLY RULE SOME SNOW MIXING IN
SO PLAN TO HAVE A LITTLE MIX FOR A WHILE.
.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY
141 AM CST SUN NOV 4 2012
MEDIUM RANGE MODELS IN VERY GOOD AGREEMENT THIS MORNING SHOWING
THE UPPER LEVEL RIDGE OVER THE ROCKIES WILL SLIDE EAST ACROSS THE
MIDWEST BEHIND THE TUESDAY SYSTEM. THIS RIDGING IS EXPECTED TO
SLIDE EAST PAST THE REGION THURSDAY NIGHT AND FRIDAY ALLOWING
SOUTHWEST FLOW ALOFT TO DEVELOP AS AN UPPER LEVEL LOW MOVES ACROSS
THE NORTHERN ROCKIES ONTO THE HIGH PLAINS BY SATURDAY. AT THE
SURFACE...CYCLOGENESIS SHOULD TAKE PLACE IN THE LEE OF THE
ROCKIES FRIDAY NIGHT WITH THE LOW ADVANCING NORTHEAST INTO
MINNESOTA SATURDAY. STILL SIGNIFICANT DIFFERENCES ON WHERE THE
WARM FRONT DEVELOPS WITH THE SURFACE LOW. THE GFS HAS THE WARM
FRONT ALONG THE IOWA/MISSOURI BORDER AND SHOWS PRECIPITATION
DEVELOPING NORTH OF THIS ALREADY FRIDAY WHILE THE 04.00Z ECMWF
CONTINUES TO SHOW THE WARM FRONT WELL TO THE NORTH WITH ANY
PRECIPITATION ACROSS SOUTHERN CANADA. THESE DIFFERENCES THEN
CONTINUE THROUGH THE REMAINDER OF THE PERIOD WITH THE GFS BEING
MUCH WETTER WHILE THE ECMWF KEEPS THE AREA IN THE WARM SECTOR AND
DOES NOT DEVELOP ANY PRECIPITATION UNTIL FRIDAY NIGHT INTO
SATURDAY AS THE SURFACE LOW AND COLD FRONT STARTS TO APPROACH. NO
CHANGES PLANNED TO THE MODEL CONSENSUS GRIDS AT THIS POINT WHICH
FAVOR THE DRIER ECMWF SOLUTION.
&&
.AVIATION...
1025 PM CDT SAT NOV 3 2012
AN AREA OF PCPN WAS TRACKING SOUTHEAST ACROSS SOUTHERN MN...AND WILL
MOVE ACROSS IOWA DURING THE OVERNIGHT HOURS. IT WAS MOSTLY
-RA...BUT WILL MIX WITH SOME -SN AS TEMPS CONTINUE TO COOL. VSBYS
WERE MOSTLY P6SM WITH ANY PCPN...WITH ONLY MINOR IF ANY
ACCUMULATIONS. LATEST RAP13/HRRR/NAM12 CONTINUE TO KEEP THE BULK OF
THE PCPN SOUTHWEST OF KLSE...BUT COULD MOVE ACROSS KRST. WILL
CONTINUE -SH THERE...AND LEAVE KLSE PCPN FREE FOR NOW.
FOR CIGS...SUB 3 KFT CLOUDS ARE ASSOCIATED WITH MUCH OF THE
PCPN...WITH INCREASING LOW LEVEL RH AND BUFKIT SOUNDINGS SUPPORTING
THESE LOWER CIGS. DAYTIME MIXING SHOULD PUSH CIG HEIGHTS UP DURING
THE DAY ON SUN. THAT SAID...ANOTHER SHORTWAVE TROUGH WILL PUSH
ACROSS THE REGION FOR LATE SUN NIGHT/MONDAY. SATURATION IS DEEPER
AND MORE WIDESPREAD WITH THIS FEATURE...AND A PROLONGED PERIOD OF
MVFR CIGS - OR CLOSE TO IT - LOOKS LIKELY FOR MONDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
141 AM CST SUN NOV 4 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
203 PM CST SUN NOV 4 2012
.DISCUSSION...
1040 AM CST
FOR MORNING UPDATE...
HAVE MADE SOME TWEAKS TO GOING FORECAST MAINLY WITH RESPECT TO
CLOUD COVER AND PRECIP TRENDS FOR TODAY.
MORNING RAOB ANALYSIS AND GOES WATER VAPOR IMAGERY INDICATE MID-
LEVEL SHORT WAVE PROPAGATING SOUTHEAST ACROSS THE AREA. THIS WAVE
SEEMS A BIT DISJOINTED WITH BETTER LOW LEVEL WARM ADVECTION
FORCING LINGERING TO THE WEST ACROSS IA...WHERE REGIONAL RADAR
MOSAIC INDICATES SOME WEAK RETURNS. GUIDANCE MAINTAINS THIS
THROUGH THE AFTERNOON...WITH PERSISTENT LOW LEVEL WAA AND
RESULTING LIGHT PRECIP PRODUCTION WEST/SOUTHWEST OF THE FORECAST
AREA. WEAK RADAR RETURNS OVER FAR WESTERN CWA HAVE DIMINISHED
DURING THE MORNING...AND HAVE THUS REMOVED MENTIONABLE POPS FROM
THOSE AREAS. FARTHER EAST...LAKE EFFECT RAIN SHOWERS CONTINUE TO
DEVELOP ALONG MID-LAKE CONVERGENCE ZONE AND MOVE INLAND ACROSS
NORTHWEST INDIANA COUNTIES. OF THE VARIOUS SHORT TERM/HIGH
RESOLUTION GUIDANCE SETS THE RAP SEEMS TO BE HANDLING THE CURRENT
LAKE PLUME THE BEST...AND WHILE IT WEAKENS THE ORGANIZATION OF THE
LOW LEVEL WIND FIELD AND CONVERGENCE ZONE THIS AFTERNOON...IT
MAINTAINS THE IDEA OF SOME SPOTTY LIGHT PRECIP FROM FAR ABOUT THE
STATE LINE AREA EAST INTO WESTERN PORTER COUNTY THIS AFTERNOON.
FORECAST SOUNDINGS INDICATE SOME GRADUAL WARMING ALOFT BY LATE
AFTERNOON AND A SMALL DECREASE IN LAKE-850 MB DELTA T VALUES FROM
ABOUT 17 DEG TO 15 DEG...AS WELL AS LOWERING OF EQUILIBRIUM
HEIGHTS FROM ABOUT 5500-6000 FT TO LESS THAN 5000 FT BY 00Z. THUS
SUSPECT LAKE EFFECT SHOWERS WILL BECOME WEAKER AND A LITTLE LESS
ORGANIZED DURING THE MID/LATE AFTERNOON HOURS.
OTHERWISE...ADJUSTED HOURLY SKY COVER GRIDS A BIT TO ACCOUNT FOR A
LITTLE LESS CLOUD COVER NEAR THE IL/WI STATE LINE THROUGH THIS
AFTERNOON.
RATZER
//PREV DISCUSSION...
202 AM CST
A RELATIVELY QUIET PERIOD OF WEATHER TO CONTINUE FOR THE NEXT FEW
DAYS...WITH THE NEXT SIGNIFICANT CHANCE FOR PCPN SETTING UP FOR
ELECTION DAY TUESDAY.
FOR THE REMAINDER OF THE NIGHT AND INTO SUNDAY...THE MAIN WEATHER
CONCERNS WILL BE A CHANCE FOR SOME LIGHT SNOW SHOWERS OR FLURRIES IN
THE ROCKFORD AREA AND LAKE EFFECT RAIN SHOWERS OVER NORTHERN
PORTIONS OF LAKE AND PORTER COUNTIES IN INDIANA AND SOUTHEASTERN
COOK COUNTY...ESPECIALLY NEAR THE LAKE. LATEST RADAR IMAGERY SHOWS
A PERSISTENT AREA OF LAKE EFFECT SHOWERS OVER SOUTHERN LAKE
MICHIGAN...FOCUSED IN A WEAK CONVERGENCE ZONE SET UP BY AN OFFSHORE
LAND BREEZE FLOW PATTERN. COUPLED WITH LAKE SFC TO 850MB DELTA-T
VALUES BTWN 15-18C...THE LAKE EFFECT SHOWERS SHOULD PERSIST THROUGH
THE MORNING HOURS. AS A WEAK RIDGE OF HIGH PRESSURE BUILDS ACROSS
THE UPPER MISSISSIPPI VALLEY AND INTO WI/IL TODAY...WEAK NORTHERLY
LOW LEVEL WIND FLOW WILL PERSIST OVER THE REGION AND CONDITIONS WILL
REMAIN CONDUCIVE TO SCT LAKE EFFECT RAIN SHOWERS AND ENHANCED
CLOUDINESS THROUGH THE DAY TODAY AND INTO THIS EVENING. ALSO...HAVE
BEEN MONITORING AN AREA PF PCPN ASSOCIATED WITH A SHORTWAVE DROPPING
THROUGH NERN IA WHICH IS GENERATING SOME LIGHT PCPN. AS SFC
TEMPERATURES DROP INTO THE LOWER 30S AND POSSIBLY SOME UPPER
20S...SOME VERY LIGHT SNOW OR FLURRIES ARE POSSIBLE OVER NWRN
IL...INCLUDING THE ROCKFORD AREA. HOWEVER...WITH LITTLE AVAILABLE
DEEP LAYER MOISTURE...LAST EVENING`S SOUNDING FROM DVN INDICATED
PWAT OF ONLY 0.42 INCHES...NO MEASURABLE PCPN IS EXPECTED. AS THE
SHORT WAVES QUICKLY DROPS INTO CENTRAL IL THIS AFTERNOON AND
CONTINUES INTO SRN INDIANA THIS EVENING...ANY PCPN POTENTIAL OVER
THE WRN PORTIONS OF THE CWA SHOULD COME TO AN END BY AROUND NOON.
THE UPPER LEVEL PATTERN IS BECOMING SOMEWHAT BLOCKY AS A DEEP POLAR
VORTEX DROPS SWD THROUGH QUEBEC SUNDAY NIGHT AND MONDAY WHILE UPPER
RIDGING BUILDS EWD FROM THE WEST COAST INTO THE ROCKIES. THIS WILL
SET UP A PERIOD OF NWLY FLOW ALOFT OVER THE UPPER MISSISSIPPI VALLEY
AND INTO THE MIDWEST WITH A SERIES OF SHORTWAVES TRACKING NEAR THE
LOCAL AREA. THE FIRST IN THE SERIES WILL TRACK THROUGH IOWA AND
MISSOURI ON MONDAY AND INTO THE LOWER OHIO VALLEY MONDAY NIGHT.
THIS SYSTEM WILL GENERATE AN AREA OF PCPN...HOWEVER...IT SHOULD
REMAIN TOO FAR TO THE WEST TO BRING ANY PCPN INTO NCNRTL/NERN IL OR
NWRN INDIANA. MODEL GUIDANCE IS VERY CONSISTENT ON THE TRACK OF
THIS FEATURE...THOUGH THERE IS SOME DISAGREEMENT ON THE
STRENGTH...WITH THE NAM A BIT WEAKER THAN THE GFS OR ECMWF.
HOWEVER...REGARDLESS OF THESE DIFFERENCES...CONFIDENCE IS HIGH FOR A
DRY FORECAST OVER THE CWA. THE NEXT SYSTEM IS SHAPING UP TO HAVE A
MORE DIRECT IMPACT ON THE LOCAL AREA AS THE SHORTWAVE SHOULD TRACK
THROUGH THE WESTERN GREAT LAKES AND MIDDLE MISSISSIPPI VALLEY. A
WEAK COLD FRONT WILL ACCOMPANY THE THE SHORTWAVE ADDING LOW LEVEL
FORCING TO THE MIDLEVEL FORCING OF THE SHORTWAVE. ALSO...THIS
SYSTEM IS PACIFIC-SOURCED...AND CURRENTLY OVER THE GULF OF
ALASKA...SO IT IS NOT EXPECTED TO BRING ANY SIGNIFICANTLY COLDER
AIR...WITH TEMPERATURES ON TUESDAY EXPECTED TO REACH INTO THE UPPER
40S TO AROUND 50F. WITH REASONABLY DECENT CONTINUITY AND
CONSISTENCY AMONG THE MODELS ON THIS SYSTEM...CONFIDENCE IS
RELATIVELY HIGH FOR MEASURABLE LIQUID PCPN WITH THIS SYSTEM.
ALSO...AS SWLY WINDS INCREASE IN ADVANCE OF THE APPROACHING COLD
FRONT...ELECTION DAY SHOULD BE BREEZY AND WET.
FOR THE LONGER TERM...CONFIDENCE STARTS TO QUICKLY DETERIORATE. BY
LATE TUESDAY...THE POLAR VORTEX OVER SRN QUEBEC SHOULD FINALLY KICK
OUT TO THE EAST...ALLOWING FOR SOME PROGRESSION TO THE UPPER LEVEL
PATTERN. THERE IS SOME DISAGREEMENT BETWEEN THE GFS AND ECMWF ON
HOW FAR EAST THE UPPER RIDGE WILL PENETRATE EAST OF THE MISSISSIPPI
RIVER. THE ECMWF IS MUCH MORE AMPLIFIED THAN THE GFS...WHICH WOULD
HAVE A SIGNIFICANT IMPACT ON THE TRAIN OF NORTHERN STREAM
SHORTWAVES. THESE MODEL DIFFERENCES COME INTO PLAY BY THE END OF
THE PERIOD...ESPECIALLY FOR FRIDAY AND SATURDAY. THE MORE AMPLIFIED
ECMWF SOLUTION WOULD SUGGEST BETTER CHANCES FOR PCPN THAN THE
FLATTER...BROADER UPPER LEVEL PATTERN OF THE GFS. SO...WILL NOT
MAKE ANY SIGNIFICANT CHANGES TO THE LATTER PORTIONS OF THE LONG
RANGE FORECAST...AND JUST KEEP SOME LOW POPS FOR THE NORTHERN
PORTIONS OF THE CWA FOR FRIDAY NIGHT AND SATURDAY WHEN THE ECMWF
BRINGS A SOUTHERN STREAM SHORTWAVE THROUGH THE AREA.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* WIND DIRECTIONS CONTINUE TO BE UNCERTAIN. RADAR AND VISIBLE
SATELLITE SHOW THE APPROACH OF A LINE OF CUMULUS FROM THE EAST
BEHIND WHICH THE LAKE BREEZE SHOULD MAYBE FINALLY TURN THINGS
TO THE NORTHEAST AS HAS BEEN ANTICIPATED ALL AFTERNOON.
* LOWERING CEILINGS TONIGHT BUT STILL LIKELY TO STAY ABOVE IFR.
LENNING
//DISCUSSION...UPDATED 18Z...
A WEAK PRESSURE GRADIENT OVERHEAD IS ALLOWING WINDS TO FLUCTUATE
IN BOTH SPEED AND DIRECTION EARLY THIS AFTERNOON. OVERALL THE
TREND WOULD STILL APPEAR TO FAVOR A NORTHEASTERLY
DIRECTION...ESPECIALLY IF A WEAK LAKE BREEZE CAN DEVELOP.
DEVELOPING CUMULUS ALONG THE WATERFRONT SUGGESTS THIS MAY BE THE
CASE...BUT ALSO RAISES THE POSSIBILITY OF SOMEWHAT LOWER CEILINGS
IN THE 3500 FT RANGE THIS AFTERNOON. BOTH TRENDS WILL CONTINUE TO
BE MONITORED. IF NOT THIS AFTERNOON...LOWER CIGS DO LOOK FAVORABLE
THIS EVENING INTO TOMORROW MORNING IF DEVELOPING NORTHEAST FLOW
OFF THE LAKE PUSHES THE CLOUDS NOW SEEN OVER INDIANA FARTHER WEST
INTO DOWNTOWN CHICAGO. TO A LESSER DEGREE THE SAME TREND IS
EXPECTED AT RFD BUT FOR DIFFERENT REASONS. THE AREA OUT WEST WILL
BE CLOSER TO A LOW PRESSURE SYSTEM DROPPING THROUGH THE MIDWEST
OVERNIGHT...BUT LIKELY NOT CLOSE ENOUGH TO BE UNDER THE
PRECIPITATION SHIELD.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM TO HIGH CONFIDENCE ON WINDS THIS AFTERNOON.
* MEDIUM CONFIDENCE ON CEILING TRENDS OVERNIGHT.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR.
TUESDAY...SHRA LIKELY TUESDAY AFTERNOON WITH A CHC OTHERWISE
DURING THE DAY AND NIGHT. CHC OF MVFR.
WEDNESDAY-THURSDAY...VFR.
FRIDAY...SLIGHT CHC OF -RA DURING THE NIGHT.
SATURDAY...SLIGHT CHC OF -RA DURING THE DAY.
MTF
&&
.MARINE...
102 PM CST
FAIRLY BENIGN WEATHER ON THE LAKE THE NEXT 36 HOURS AS WEAK RIDGE OF
HIGH PRESSURE MOVES ACROSS THE REGION. BY LATER MONDAY NIGHT INTO
TUESDAY SOUTHERLY WINDS WILL INCREASE AHEAD OF A FAST MOVING CLIPPER
LIKE SYSTEM DROPPING SOUTHEAST INTO THE UPPER GREAT LAKES. COULD SEE
SOUTHWEST WINDS APPROACH LOW END GALES TUESDAY OVER NORTHERN
PORTIONS OF THE LAKE BEFORE COLD FRONT SWEEPS ACROSS THE LAKE
TUESDAY NIGHT WITH A HEALTHY SHOT OF COLD AIR ADVECTION IN THE WAKE
OF THE FRONT LEADING TO A PERIOD OF FRESH NORTHWEST WINDS LATER
TUESDAY NIGHT INTO EARLY WEDNESDAY BEFORE TRANSIENT HIGH PRESSURE
BUILDS INTO THE AREA. MEDIUM RANGE MODELS HINT AT A FAIRLY POTENT
STORM SYSTEM TRACKING INTO THE NORTHERN PLAINS LATE NEXT WEEK INTO
NEXT WEEKEND WITH STRONG SOUTHERLIES A THREAT AHEAD OF THAT SYSTEM.
IZZI
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
102 PM CST SUN NOV 4 2012
.DISCUSSION...
1040 AM CST
FOR MORNING UPDATE...
HAVE MADE SOME TWEAKS TO GOING FORECAST MAINLY WITH RESPECT TO
CLOUD COVER AND PRECIP TRENDS FOR TODAY.
MORNING RAOB ANALYSIS AND GOES WATER VAPOR IMAGERY INDICATE MID-
LEVEL SHORT WAVE PROPAGATING SOUTHEAST ACROSS THE AREA. THIS WAVE
SEEMS A BIT DISJOINTED WITH BETTER LOW LEVEL WARM ADVECTION
FORCING LINGERING TO THE WEST ACROSS IA...WHERE REGIONAL RADAR
MOSAIC INDICATES SOME WEAK RETURNS. GUIDANCE MAINTAINS THIS
THROUGH THE AFTERNOON...WITH PERSISTENT LOW LEVEL WAA AND
RESULTING LIGHT PRECIP PRODUCTION WEST/SOUTHWEST OF THE FORECAST
AREA. WEAK RADAR RETURNS OVER FAR WESTERN CWA HAVE DIMINISHED
DURING THE MORNING...AND HAVE THUS REMOVED MENTIONABLE POPS FROM
THOSE AREAS. FARTHER EAST...LAKE EFFECT RAIN SHOWERS CONTINUE TO
DEVELOP ALONG MID-LAKE CONVERGENCE ZONE AND MOVE INLAND ACROSS
NORTHWEST INDIANA COUNTIES. OF THE VARIOUS SHORT TERM/HIGH
RESOLUTION GUIDANCE SETS THE RAP SEEMS TO BE HANDLING THE CURRENT
LAKE PLUME THE BEST...AND WHILE IT WEAKENS THE ORGANIZATION OF THE
LOW LEVEL WIND FIELD AND CONVERGENCE ZONE THIS AFTERNOON...IT
MAINTAINS THE IDEA OF SOME SPOTTY LIGHT PRECIP FROM FAR ABOUT THE
STATE LINE AREA EAST INTO WESTERN PORTER COUNTY THIS AFTERNOON.
FORECAST SOUNDINGS INDICATE SOME GRADUAL WARMING ALOFT BY LATE
AFTERNOON AND A SMALL DECREASE IN LAKE-850 MB DELTA T VALUES FROM
ABOUT 17 DEG TO 15 DEG...AS WELL AS LOWERING OF EQUILIBRIUM
HEIGHTS FROM ABOUT 5500-6000 FT TO LESS THAN 5000 FT BY 00Z. THUS
SUSPECT LAKE EFFECT SHOWERS WILL BECOME WEAKER AND A LITTLE LESS
ORGANIZED DURING THE MID/LATE AFTERNOON HOURS.
OTHERWISE...ADJUSTED HOURLY SKY COVER GRIDS A BIT TO ACCOUNT FOR A
LITTLE LESS CLOUD COVER NEAR THE IL/WI STATE LINE THROUGH THIS
AFTERNOON.
RATZER
//PREV DISCUSSION...
202 AM CST
A RELATIVELY QUIET PERIOD OF WEATHER TO CONTINUE FOR THE NEXT FEW
DAYS...WITH THE NEXT SIGNIFICANT CHANCE FOR PCPN SETTING UP FOR
ELECTION DAY TUESDAY.
FOR THE REMAINDER OF THE NIGHT AND INTO SUNDAY...THE MAIN WEATHER
CONCERNS WILL BE A CHANCE FOR SOME LIGHT SNOW SHOWERS OR FLURRIES IN
THE ROCKFORD AREA AND LAKE EFFECT RAIN SHOWERS OVER NORTHERN
PORTIONS OF LAKE AND PORTER COUNTIES IN INDIANA AND SOUTHEASTERN
COOK COUNTY...ESPECIALLY NEAR THE LAKE. LATEST RADAR IMAGERY SHOWS
A PERSISTENT AREA OF LAKE EFFECT SHOWERS OVER SOUTHERN LAKE
MICHIGAN...FOCUSED IN A WEAK CONVERGENCE ZONE SET UP BY AN OFFSHORE
LAND BREEZE FLOW PATTERN. COUPLED WITH LAKE SFC TO 850MB DELTA-T
VALUES BTWN 15-18C...THE LAKE EFFECT SHOWERS SHOULD PERSIST THROUGH
THE MORNING HOURS. AS A WEAK RIDGE OF HIGH PRESSURE BUILDS ACROSS
THE UPPER MISSISSIPPI VALLEY AND INTO WI/IL TODAY...WEAK NORTHERLY
LOW LEVEL WIND FLOW WILL PERSIST OVER THE REGION AND CONDITIONS WILL
REMAIN CONDUCIVE TO SCT LAKE EFFECT RAIN SHOWERS AND ENHANCED
CLOUDINESS THROUGH THE DAY TODAY AND INTO THIS EVENING. ALSO...HAVE
BEEN MONITORING AN AREA PF PCPN ASSOCIATED WITH A SHORTWAVE DROPPING
THROUGH NERN IA WHICH IS GENERATING SOME LIGHT PCPN. AS SFC
TEMPERATURES DROP INTO THE LOWER 30S AND POSSIBLY SOME UPPER
20S...SOME VERY LIGHT SNOW OR FLURRIES ARE POSSIBLE OVER NWRN
IL...INCLUDING THE ROCKFORD AREA. HOWEVER...WITH LITTLE AVAILABLE
DEEP LAYER MOISTURE...LAST EVENING`S SOUNDING FROM DVN INDICATED
PWAT OF ONLY 0.42 INCHES...NO MEASURABLE PCPN IS EXPECTED. AS THE
SHORT WAVES QUICKLY DROPS INTO CENTRAL IL THIS AFTERNOON AND
CONTINUES INTO SRN INDIANA THIS EVENING...ANY PCPN POTENTIAL OVER
THE WRN PORTIONS OF THE CWA SHOULD COME TO AN END BY AROUND NOON.
THE UPPER LEVEL PATTERN IS BECOMING SOMEWHAT BLOCKY AS A DEEP POLAR
VORTEX DROPS SWD THROUGH QUEBEC SUNDAY NIGHT AND MONDAY WHILE UPPER
RIDGING BUILDS EWD FROM THE WEST COAST INTO THE ROCKIES. THIS WILL
SET UP A PERIOD OF NWLY FLOW ALOFT OVER THE UPPER MISSISSIPPI VALLEY
AND INTO THE MIDWEST WITH A SERIES OF SHORTWAVES TRACKING NEAR THE
LOCAL AREA. THE FIRST IN THE SERIES WILL TRACK THROUGH IOWA AND
MISSOURI ON MONDAY AND INTO THE LOWER OHIO VALLEY MONDAY NIGHT.
THIS SYSTEM WILL GENERATE AN AREA OF PCPN...HOWEVER...IT SHOULD
REMAIN TOO FAR TO THE WEST TO BRING ANY PCPN INTO NCNRTL/NERN IL OR
NWRN INDIANA. MODEL GUIDANCE IS VERY CONSISTENT ON THE TRACK OF
THIS FEATURE...THOUGH THERE IS SOME DISAGREEMENT ON THE
STRENGTH...WITH THE NAM A BIT WEAKER THAN THE GFS OR ECMWF.
HOWEVER...REGARDLESS OF THESE DIFFERENCES...CONFIDENCE IS HIGH FOR A
DRY FORECAST OVER THE CWA. THE NEXT SYSTEM IS SHAPING UP TO HAVE A
MORE DIRECT IMPACT ON THE LOCAL AREA AS THE SHORTWAVE SHOULD TRACK
THROUGH THE WESTERN GREAT LAKES AND MIDDLE MISSISSIPPI VALLEY. A
WEAK COLD FRONT WILL ACCOMPANY THE THE SHORTWAVE ADDING LOW LEVEL
FORCING TO THE MIDLEVEL FORCING OF THE SHORTWAVE. ALSO...THIS
SYSTEM IS PACIFIC-SOURCED...AND CURRENTLY OVER THE GULF OF
ALASKA...SO IT IS NOT EXPECTED TO BRING ANY SIGNIFICANTLY COLDER
AIR...WITH TEMPERATURES ON TUESDAY EXPECTED TO REACH INTO THE UPPER
40S TO AROUND 50F. WITH REASONABLY DECENT CONTINUITY AND
CONSISTENCY AMONG THE MODELS ON THIS SYSTEM...CONFIDENCE IS
RELATIVELY HIGH FOR MEASURABLE LIQUID PCPN WITH THIS SYSTEM.
ALSO...AS SWLY WINDS INCREASE IN ADVANCE OF THE APPROACHING COLD
FRONT...ELECTION DAY SHOULD BE BREEZY AND WET.
FOR THE LONGER TERM...CONFIDENCE STARTS TO QUICKLY DETERIORATE. BY
LATE TUESDAY...THE POLAR VORTEX OVER SRN QUEBEC SHOULD FINALLY KICK
OUT TO THE EAST...ALLOWING FOR SOME PROGRESSION TO THE UPPER LEVEL
PATTERN. THERE IS SOME DISAGREEMENT BETWEEN THE GFS AND ECMWF ON
HOW FAR EAST THE UPPER RIDGE WILL PENETRATE EAST OF THE MISSISSIPPI
RIVER. THE ECMWF IS MUCH MORE AMPLIFIED THAN THE GFS...WHICH WOULD
HAVE A SIGNIFICANT IMPACT ON THE TRAIN OF NORTHERN STREAM
SHORTWAVES. THESE MODEL DIFFERENCES COME INTO PLAY BY THE END OF
THE PERIOD...ESPECIALLY FOR FRIDAY AND SATURDAY. THE MORE AMPLIFIED
ECMWF SOLUTION WOULD SUGGEST BETTER CHANCES FOR PCPN THAN THE
FLATTER...BROADER UPPER LEVEL PATTERN OF THE GFS. SO...WILL NOT
MAKE ANY SIGNIFICANT CHANGES TO THE LATTER PORTIONS OF THE LONG
RANGE FORECAST...AND JUST KEEP SOME LOW POPS FOR THE NORTHERN
PORTIONS OF THE CWA FOR FRIDAY NIGHT AND SATURDAY WHEN THE ECMWF
BRINGS A SOUTHERN STREAM SHORTWAVE THROUGH THE AREA.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* WINDS WILL BE RELATIVELY LIGHT TODAY BUT DIRECTION WILL BE
SOMEWHAT UNCERTAIN...VARYING FROM NW TO ENE. POSSIBLE LAKE
BREEZE THIS AFTERNOON WOULD FAVOR THE NE QUADRANT.
* POSSIBLE LOWER CEILINGS TONIGHT INTO TOMORROW MORNING...THOUGH
LIKELY STAYING ABOVE IFR.
LENNING
//DISCUSSION...UPDATED 18Z...
A WEAK PRESSURE GRADIENT OVERHEAD IS ALLOWING WINDS TO FLUCTUATE
IN BOTH SPEED AND DIRECTION EARLY THIS AFTERNOON. OVERALL THE
TREND WOULD STILL APPEAR TO FAVOR A NORTHEASTERLY
DIRECTION...ESPECIALLY IF A WEAK LAKE BREEZE CAN DEVELOP.
DEVELOPING CUMULUS ALONG THE WATERFRONT SUGGESTS THIS MAY BE THE
CASE...BUT ALSO RAISES THE POSSIBILITY OF SOMEWHAT LOWER CEILINGS
IN THE 3500 FT RANGE THIS AFTERNOON. BOTH TRENDS WILL CONTINUE TO
BE MONITORED. IF NOT THIS AFTERNOON...LOWER CIGS DO LOOK FAVORABLE
THIS EVENING INTO TOMORROW MORNING IF DEVELOPING NORTHEAST FLOW
OFF THE LAKE PUSHES THE CLOUDS NOW SEEN OVER INDIANA FARTHER WEST
INTO DOWNTOWN CHICAGO. TO A LESSER DEGREE THE SAME TREND IS
EXPECTED AT RFD BUT FOR DIFFERENT REASONS. THE AREA OUT WEST WILL
BE CLOSER TO A LOW PRESSURE SYSTEM DROPPING THROUGH THE MIDWEST
OVERNIGHT...BUT LIKELY NOT CLOSE ENOUGH TO BE UNDER THE
PRECIPITATION SHIELD.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE IN WIND SPEEDS GENERALLY BELOW 10 KT BUT LOW
CONFIDENCE IN EXACT DIRECTION.
* MEDIUM CONFIDENCE IN TREND OF LOWER CEILINGS OVERNIGHT.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR.
TUESDAY...SHRA LIKELY TUESDAY AFTERNOON WITH A CHC OTHERWISE
DURING THE DAY AND NIGHT. CHC OF MVFR.
WEDNESDAY-THURSDAY...VFR.
FRIDAY...SLIGHT CHC OF -RA DURING THE NIGHT.
SATURDAY...SLIGHT CHC OF -RA DURING THE DAY.
MTF
&&
.MARINE...
102 PM CST
FAIRLY BENIGN WEATHER ON THE LAKE THE NEXT 36 HOURS AS WEAK RIDGE OF
HIGH PRESSURE MOVES ACROSS THE REGION. BY LATER MONDAY NIGHT INTO
TUESDAY SOUTHERLY WINDS WILL INCREASE AHEAD OF A FAST MOVING CLIPPER
LIKE SYSTEM DROPPING SOUTHEAST INTO THE UPPER GREAT LAKES. COULD SEE
SOUTHWEST WINDS APPROACH LOW END GALES TUESDAY OVER NORTHERN
PORTIONS OF THE LAKE BEFORE COLD FRONT SWEEPS ACROSS THE LAKE
TUESDAY NIGHT WITH A HEALTHY SHOT OF COLD AIR ADVECTION IN THE WAKE
OF THE FRONT LEADING TO A PERIOD OF FRESH NORTHWEST WINDS LATER
TUESDAY NIGHT INTO EARLY WEDNESDAY BEFORE TRANSIENT HIGH PRESSURE
BUILDS INTO THE AREA. MEDIUM RANGE MODELS HINT AT A FAIRLY POTENT
STORM SYSTEM TRACKING INTO THE NORTHERN PLAINS LATE NEXT WEEK INTO
NEXT WEEKEND WITH STRONG SOUTHERLIES A THREAT AHEAD OF THAT SYSTEM.
IZZI
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1217 PM CST SUN NOV 4 2012
.DISCUSSION...
1040 AM CST
FOR MORNING UPDATE...
HAVE MADE SOME TWEAKS TO GOING FORECAST MAINLY WITH RESPECT TO
CLOUD COVER AND PRECIP TRENDS FOR TODAY.
MORNING RAOB ANALYSIS AND GOES WATER VAPOR IMAGERY INDICATE MID-
LEVEL SHORT WAVE PROPAGATING SOUTHEAST ACROSS THE AREA. THIS WAVE
SEEMS A BIT DISJOINTED WITH BETTER LOW LEVEL WARM ADVECTION
FORCING LINGERING TO THE WEST ACROSS IA...WHERE REGIONAL RADAR
MOSAIC INDICATES SOME WEAK RETURNS. GUIDANCE MAINTAINS THIS
THROUGH THE AFTERNOON...WITH PERSISTENT LOW LEVEL WAA AND
RESULTING LIGHT PRECIP PRODUCTION WEST/SOUTHWEST OF THE FORECAST
AREA. WEAK RADAR RETURNS OVER FAR WESTERN CWA HAVE DIMINISHED
DURING THE MORNING...AND HAVE THUS REMOVED MENTIONABLE POPS FROM
THOSE AREAS. FARTHER EAST...LAKE EFFECT RAIN SHOWERS CONTINUE TO
DEVELOP ALONG MID-LAKE CONVERGENCE ZONE AND MOVE INLAND ACROSS
NORTHWEST INDIANA COUNTIES. OF THE VARIOUS SHORT TERM/HIGH
RESOLUTION GUIDANCE SETS THE RAP SEEMS TO BE HANDLING THE CURRENT
LAKE PLUME THE BEST...AND WHILE IT WEAKENS THE ORGANIZATION OF THE
LOW LEVEL WIND FIELD AND CONVERGENCE ZONE THIS AFTERNOON...IT
MAINTAINS THE IDEA OF SOME SPOTTY LIGHT PRECIP FROM FAR ABOUT THE
STATE LINE AREA EAST INTO WESTERN PORTER COUNTY THIS AFTERNOON.
FORECAST SOUNDINGS INDICATE SOME GRADUAL WARMING ALOFT BY LATE
AFTERNOON AND A SMALL DECREASE IN LAKE-850 MB DELTA T VALUES FROM
ABOUT 17 DEG TO 15 DEG...AS WELL AS LOWERING OF EQUILIBRIUM
HEIGHTS FROM ABOUT 5500-6000 FT TO LESS THAN 5000 FT BY 00Z. THUS
SUSPECT LAKE EFFECT SHOWERS WILL BECOME WEAKER AND A LITTLE LESS
ORGANIZED DURING THE MID/LATE AFTERNOON HOURS.
OTHERWISE...ADJUSTED HOURLY SKY COVER GRIDS A BIT TO ACCOUNT FOR A
LITTLE LESS CLOUD COVER NEAR THE IL/WI STATE LINE THROUGH THIS
AFTERNOON.
RATZER
//PREV DISCUSSION...
202 AM CST
A RELATIVELY QUIET PERIOD OF WEATHER TO CONTINUE FOR THE NEXT FEW
DAYS...WITH THE NEXT SIGNIFICANT CHANCE FOR PCPN SETTING UP FOR
ELECTION DAY TUESDAY.
FOR THE REMAINDER OF THE NIGHT AND INTO SUNDAY...THE MAIN WEATHER
CONCERNS WILL BE A CHANCE FOR SOME LIGHT SNOW SHOWERS OR FLURRIES IN
THE ROCKFORD AREA AND LAKE EFFECT RAIN SHOWERS OVER NORTHERN
PORTIONS OF LAKE AND PORTER COUNTIES IN INDIANA AND SOUTHEASTERN
COOK COUNTY...ESPECIALLY NEAR THE LAKE. LATEST RADAR IMAGERY SHOWS
A PERSISTENT AREA OF LAKE EFFECT SHOWERS OVER SOUTHERN LAKE
MICHIGAN...FOCUSED IN A WEAK CONVERGENCE ZONE SET UP BY AN OFFSHORE
LAND BREEZE FLOW PATTERN. COUPLED WITH LAKE SFC TO 850MB DELTA-T
VALUES BTWN 15-18C...THE LAKE EFFECT SHOWERS SHOULD PERSIST THROUGH
THE MORNING HOURS. AS A WEAK RIDGE OF HIGH PRESSURE BUILDS ACROSS
THE UPPER MISSISSIPPI VALLEY AND INTO WI/IL TODAY...WEAK NORTHERLY
LOW LEVEL WIND FLOW WILL PERSIST OVER THE REGION AND CONDITIONS WILL
REMAIN CONDUCIVE TO SCT LAKE EFFECT RAIN SHOWERS AND ENHANCED
CLOUDINESS THROUGH THE DAY TODAY AND INTO THIS EVENING. ALSO...HAVE
BEEN MONITORING AN AREA PF PCPN ASSOCIATED WITH A SHORTWAVE DROPPING
THROUGH NERN IA WHICH IS GENERATING SOME LIGHT PCPN. AS SFC
TEMPERATURES DROP INTO THE LOWER 30S AND POSSIBLY SOME UPPER
20S...SOME VERY LIGHT SNOW OR FLURRIES ARE POSSIBLE OVER NWRN
IL...INCLUDING THE ROCKFORD AREA. HOWEVER...WITH LITTLE AVAILABLE
DEEP LAYER MOISTURE...LAST EVENING`S SOUNDING FROM DVN INDICATED
PWAT OF ONLY 0.42 INCHES...NO MEASURABLE PCPN IS EXPECTED. AS THE
SHORT WAVES QUICKLY DROPS INTO CENTRAL IL THIS AFTERNOON AND
CONTINUES INTO SRN INDIANA THIS EVENING...ANY PCPN POTENTIAL OVER
THE WRN PORTIONS OF THE CWA SHOULD COME TO AN END BY AROUND NOON.
THE UPPER LEVEL PATTERN IS BECOMING SOMEWHAT BLOCKY AS A DEEP POLAR
VORTEX DROPS SWD THROUGH QUEBEC SUNDAY NIGHT AND MONDAY WHILE UPPER
RIDGING BUILDS EWD FROM THE WEST COAST INTO THE ROCKIES. THIS WILL
SET UP A PERIOD OF NWLY FLOW ALOFT OVER THE UPPER MISSISSIPPI VALLEY
AND INTO THE MIDWEST WITH A SERIES OF SHORTWAVES TRACKING NEAR THE
LOCAL AREA. THE FIRST IN THE SERIES WILL TRACK THROUGH IOWA AND
MISSOURI ON MONDAY AND INTO THE LOWER OHIO VALLEY MONDAY NIGHT.
THIS SYSTEM WILL GENERATE AN AREA OF PCPN...HOWEVER...IT SHOULD
REMAIN TOO FAR TO THE WEST TO BRING ANY PCPN INTO NCNRTL/NERN IL OR
NWRN INDIANA. MODEL GUIDANCE IS VERY CONSISTENT ON THE TRACK OF
THIS FEATURE...THOUGH THERE IS SOME DISAGREEMENT ON THE
STRENGTH...WITH THE NAM A BIT WEAKER THAN THE GFS OR ECMWF.
HOWEVER...REGARDLESS OF THESE DIFFERENCES...CONFIDENCE IS HIGH FOR A
DRY FORECAST OVER THE CWA. THE NEXT SYSTEM IS SHAPING UP TO HAVE A
MORE DIRECT IMPACT ON THE LOCAL AREA AS THE SHORTWAVE SHOULD TRACK
THROUGH THE WESTERN GREAT LAKES AND MIDDLE MISSISSIPPI VALLEY. A
WEAK COLD FRONT WILL ACCOMPANY THE THE SHORTWAVE ADDING LOW LEVEL
FORCING TO THE MIDLEVEL FORCING OF THE SHORTWAVE. ALSO...THIS
SYSTEM IS PACIFIC-SOURCED...AND CURRENTLY OVER THE GULF OF
ALASKA...SO IT IS NOT EXPECTED TO BRING ANY SIGNIFICANTLY COLDER
AIR...WITH TEMPERATURES ON TUESDAY EXPECTED TO REACH INTO THE UPPER
40S TO AROUND 50F. WITH REASONABLY DECENT CONTINUITY AND
CONSISTENCY AMONG THE MODELS ON THIS SYSTEM...CONFIDENCE IS
RELATIVELY HIGH FOR MEASURABLE LIQUID PCPN WITH THIS SYSTEM.
ALSO...AS SWLY WINDS INCREASE IN ADVANCE OF THE APPROACHING COLD
FRONT...ELECTION DAY SHOULD BE BREEZY AND WET.
FOR THE LONGER TERM...CONFIDENCE STARTS TO QUICKLY DETERIORATE. BY
LATE TUESDAY...THE POLAR VORTEX OVER SRN QUEBEC SHOULD FINALLY KICK
OUT TO THE EAST...ALLOWING FOR SOME PROGRESSION TO THE UPPER LEVEL
PATTERN. THERE IS SOME DISAGREEMENT BETWEEN THE GFS AND ECMWF ON
HOW FAR EAST THE UPPER RIDGE WILL PENETRATE EAST OF THE MISSISSIPPI
RIVER. THE ECMWF IS MUCH MORE AMPLIFIED THAN THE GFS...WHICH WOULD
HAVE A SIGNIFICANT IMPACT ON THE TRAIN OF NORTHERN STREAM
SHORTWAVES. THESE MODEL DIFFERENCES COME INTO PLAY BY THE END OF
THE PERIOD...ESPECIALLY FOR FRIDAY AND SATURDAY. THE MORE AMPLIFIED
ECMWF SOLUTION WOULD SUGGEST BETTER CHANCES FOR PCPN THAN THE
FLATTER...BROADER UPPER LEVEL PATTERN OF THE GFS. SO...WILL NOT
MAKE ANY SIGNIFICANT CHANGES TO THE LATTER PORTIONS OF THE LONG
RANGE FORECAST...AND JUST KEEP SOME LOW POPS FOR THE NORTHERN
PORTIONS OF THE CWA FOR FRIDAY NIGHT AND SATURDAY WHEN THE ECMWF
BRINGS A SOUTHERN STREAM SHORTWAVE THROUGH THE AREA.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* WINDS WILL BE RELATIVELY LIGHT TODAY BUT DIRECTION WILL BE
SOMEWHAT UNCERTAIN...VARYING FROM NW TO ENE. POSSIBLE LAKE
BREEZE THIS AFTERNOON WOULD FAVOR THE NE QUADRANT.
* POSSIBLE LOWER CEILINGS TONIGHT INTO TOMORROW MORNING...THOUGH
LIKELY STAYING ABOVE IFR.
LENNING
//DISCUSSION...UPDATED 18Z...
A WEAK PRESSURE GRADIENT OVERHEAD IS ALLOWING WINDS TO FLUCTUATE
IN BOTH SPEED AND DIRECTION EARLY THIS AFTERNOON. OVERALL THE
TREND WOULD STILL APPEAR TO FAVOR A NORTHEASTERLY
DIRECTION...ESPECIALLY IF A WEAK LAKE BREEZE CAN DEVELOP.
DEVELOPING CUMULUS ALONG THE WATERFRONT SUGGESTS THIS MAY BE THE
CASE...BUT ALSO RAISES THE POSSIBILITY OF SOMEWHAT LOWER CEILINGS
IN THE 3500 FT RANGE THIS AFTERNOON. BOTH TRENDS WILL CONTINUE TO
BE MONITORED. IF NOT THIS AFTERNOON...LOWER CIGS DO LOOK FAVORABLE
THIS EVENING INTO TOMORROW MORNING IF DEVELOPING NORTHEAST FLOW
OFF THE LAKE PUSHES THE CLOUDS NOW SEEN OVER INDIANA FARTHER WEST
INTO DOWNTOWN CHICAGO. TO A LESSER DEGREE THE SAME TREND IS
EXPECTED AT RFD BUT FOR DIFFERENT REASONS. THE AREA OUT WEST WILL
BE CLOSER TO A LOW PRESSURE SYSTEM DROPPING THROUGH THE MIDWEST
OVERNIGHT...BUT LIKELY NOT CLOSE ENOUGH TO BE UNDER THE
PRECIPITATION SHIELD.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE IN WIND SPEEDS GENERALLY BELOW 10 KT BUT LOW
CONFIDENCE IN EXACT DIRECTION.
* MEDIUM CONFIDENCE IN TREND OF LOWER CEILINGS OVERNIGHT.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR.
TUESDAY...SHRA LIKELY TUESDAY AFTERNOON WITH A CHC OTHERWISE
DURING THE DAY AND NIGHT. CHC OF MVFR.
WEDNESDAY-THURSDAY...VFR.
FRIDAY...SLIGHT CHC OF -RA DURING THE NIGHT.
SATURDAY...SLIGHT CHC OF -RA DURING THE DAY.
MTF
&&
.MARINE...
145 AM CST
AFTER A WEEK STRAIGHT OF NORTHERLY WINDS AND HIGHER WAVES...QUIET
WEATHER WILL PREVAIL INTO THE START OF THIS WEEK. WINDS MAY BE
VARIABLE AT TIMES OVER THE LAKE BY LATER TONIGHT THROUGH MONDAY AS A
HIGH PRESSURE RIDGE SLOWLY MOVES EAST OVER THE LAKE. WINDS WILL THEN
TURN SOUTHERLY LATE MONDAY NIGHT INTO TUESDAY AHEAD OF A LOW MOVING
QUICKLY SOUTHEAST ACROSS THE CANADIAN PRAIRIE PROVINCES. THIS
ALREADY HAS A GOOD PRESSURE AND PRESSURE TENDENCY PATTERN SIGNAL TO
RESULT IN 30 KT /OR POSSIBLY JUST HIGHER/ WINDS OVER THE NORTHERN
PORTION OF THE LAKE AND WAVES BRIEFLY UP TOWARD 10 FT. AN
ASSOCIATED COLD FRONT IS LIKELY TO MOVE THROUGH THE LAKE ON
TUESDAY NIGHT...BUT THIS FRONT SHOULD BE SLOWING AND WEAKENING AS
IT CROSSES THE LAKE. HIGH PRESSURE IS EXPECTED TO PREVAIL FOR A
DAY OR TWO AFTER THIS TIME...BEFORE SOUTHERLY FLOW INTO NEXT
WEEKEND.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1040 AM CST SUN NOV 4 2012
.DISCUSSION...
1040 AM CST
FOR MORNING UPDATE...
HAVE MADE SOME TWEAKS TO GOING FORECAST MAINLY WITH RESPECT TO
CLOUD COVER AND PRECIP TRENDS FOR TODAY.
MORNING RAOB ANALYSIS AND GOES WATER VAPOR IMAGERY INDICATE MID-
LEVEL SHORT WAVE PROPAGATING SOUTHEAST ACROSS THE AREA. THIS WAVE
SEEMS A BIT DISJOINTED WITH BETTER LOW LEVEL WARM ADVECTION
FORCING LINGERING TO THE WEST ACROSS IA...WHERE REGIONAL RADAR
MOSAIC INDICATES SOME WEAK RETURNS. GUIDANCE MAINTAINS THIS
THROUGH THE AFTERNOON...WITH PERSISTENT LOW LEVEL WAA AND
RESULTING LIGHT PRECIP PRODUCTION WEST/SOUTHWEST OF THE FORECAST
AREA. WEAK RADAR RETURNS OVER FAR WESTERN CWA HAVE DIMINISHED
DURING THE MORNING...AND HAVE THUS REMOVED MENTIONABLE POPS FROM
THOSE AREAS. FARTHER EAST...LAKE EFFECT RAIN SHOWERS CONTINUE TO
DEVELOP ALONG MID-LAKE CONVERGENCE ZONE AND MOVE INLAND ACROSS
NORTHWEST INDIANA COUNTIES. OF THE VARIOUS SHORT TERM/HIGH
RESOLUTION GUIDANCE SETS THE RAP SEEMS TO BE HANDLING THE CURRENT
LAKE PLUME THE BEST...AND WHILE IT WEAKENS THE ORGANIZATION OF THE
LOW LEVEL WIND FIELD AND CONVERGENCE ZONE THIS AFTERNOON...IT
MAINTAINS THE IDEA OF SOME SPOTTY LIGHT PRECIP FROM FAR ABOUT THE
STATE LINE AREA EAST INTO WESTERN PORTER COUNTY THIS AFTERNOON.
FORECAST SOUNDINGS INDICATE SOME GRADUAL WARMING ALOFT BY LATE
AFTERNOON AND A SMALL DECREASE IN LAKE-850 MB DELTA T VALUES FROM
ABOUT 17 DEG TO 15 DEG...AS WELL AS LOWERING OF EQUILIBRIUM
HEIGHTS FROM ABOUT 5500-6000 FT TO LESS THAN 5000 FT BY 00Z. THUS
SUSPECT LAKE EFFECT SHOWERS WILL BECOME WEAKER AND A LITTLE LESS
ORGANIZED DURING THE MID/LATE AFTERNOON HOURS.
OTHERWISE...ADJUSTED HOURLY SKY COVER GRIDS A BIT TO ACCOUNT FOR A
LITTLE LESS CLOUD COVER NEAR THE IL/WI STATE LINE THROUGH THIS
AFTERNOON.
RATZER
&&
.PREV DISCUSSION...
202 AM CST
A RELATIVELY QUIET PERIOD OF WEATHER TO CONTINUE FOR THE NEXT FEW
DAYS...WITH THE NEXT SIGNIFICANT CHANCE FOR PCPN SETTING UP FOR
ELECTION DAY TUESDAY.
FOR THE REMAINDER OF THE NIGHT AND INTO SUNDAY...THE MAIN WEATHER
CONCERNS WILL BE A CHANCE FOR SOME LIGHT SNOW SHOWERS OR FLURRIES IN
THE ROCKFORD AREA AND LAKE EFFECT RAIN SHOWERS OVER NORTHERN
PORTIONS OF LAKE AND PORTER COUNTIES IN INDIANA AND SOUTHEASTERN
COOK COUNTY...ESPECIALLY NEAR THE LAKE. LATEST RADAR IMAGERY SHOWS
A PERSISTENT AREA OF LAKE EFFECT SHOWERS OVER SOUTHERN LAKE
MICHIGAN...FOCUSED IN A WEAK CONVERGENCE ZONE SET UP BY AN OFFSHORE
LAND BREEZE FLOW PATTERN. COUPLED WITH LAKE SFC TO 850MB DELTA-T
VALUES BTWN 15-18C...THE LAKE EFFECT SHOWERS SHOULD PERSIST THROUGH
THE MORNING HOURS. AS A WEAK RIDGE OF HIGH PRESSURE BUILDS ACROSS
THE UPPER MISSISSIPPI VALLEY AND INTO WI/IL TODAY...WEAK NORTHERLY
LOW LEVEL WIND FLOW WILL PERSIST OVER THE REGION AND CONDITIONS WILL
REMAIN CONDUCIVE TO SCT LAKE EFFECT RAIN SHOWERS AND ENHANCED
CLOUDINESS THROUGH THE DAY TODAY AND INTO THIS EVENING. ALSO...HAVE
BEEN MONITORING AN AREA PF PCPN ASSOCIATED WITH A SHORTWAVE DROPPING
THROUGH NERN IA WHICH IS GENERATING SOME LIGHT PCPN. AS SFC
TEMPERATURES DROP INTO THE LOWER 30S AND POSSIBLY SOME UPPER
20S...SOME VERY LIGHT SNOW OR FLURRIES ARE POSSIBLE OVER NWRN
IL...INCLUDING THE ROCKFORD AREA. HOWEVER...WITH LITTLE AVAILABLE
DEEP LAYER MOISTURE...LAST EVENING`S SOUNDING FROM DVN INDICATED
PWAT OF ONLY 0.42 INCHES...NO MEASURABLE PCPN IS EXPECTED. AS THE
SHORT WAVES QUICKLY DROPS INTO CENTRAL IL THIS AFTERNOON AND
CONTINUES INTO SRN INDIANA THIS EVENING...ANY PCPN POTENTIAL OVER
THE WRN PORTIONS OF THE CWA SHOULD COME TO AN END BY AROUND NOON.
THE UPPER LEVEL PATTERN IS BECOMING SOMEWHAT BLOCKY AS A DEEP POLAR
VORTEX DROPS SWD THROUGH QUEBEC SUNDAY NIGHT AND MONDAY WHILE UPPER
RIDGING BUILDS EWD FROM THE WEST COAST INTO THE ROCKIES. THIS WILL
SET UP A PERIOD OF NWLY FLOW ALOFT OVER THE UPPER MISSISSIPPI VALLEY
AND INTO THE MIDWEST WITH A SERIES OF SHORTWAVES TRACKING NEAR THE
LOCAL AREA. THE FIRST IN THE SERIES WILL TRACK THROUGH IOWA AND
MISSOURI ON MONDAY AND INTO THE LOWER OHIO VALLEY MONDAY NIGHT.
THIS SYSTEM WILL GENERATE AN AREA OF PCPN...HOWEVER...IT SHOULD
REMAIN TOO FAR TO THE WEST TO BRING ANY PCPN INTO NCNRTL/NERN IL OR
NWRN INDIANA. MODEL GUIDANCE IS VERY CONSISTENT ON THE TRACK OF
THIS FEATURE...THOUGH THERE IS SOME DISAGREEMENT ON THE
STRENGTH...WITH THE NAM A BIT WEAKER THAN THE GFS OR ECMWF.
HOWEVER...REGARDLESS OF THESE DIFFERENCES...CONFIDENCE IS HIGH FOR A
DRY FORECAST OVER THE CWA. THE NEXT SYSTEM IS SHAPING UP TO HAVE A
MORE DIRECT IMPACT ON THE LOCAL AREA AS THE SHORTWAVE SHOULD TRACK
THROUGH THE WESTERN GREAT LAKES AND MIDDLE MISSISSIPPI VALLEY. A
WEAK COLD FRONT WILL ACCOMPANY THE THE SHORTWAVE ADDING LOW LEVEL
FORCING TO THE MIDLEVEL FORCING OF THE SHORTWAVE. ALSO...THIS
SYSTEM IS PACIFIC-SOURCED...AND CURRENTLY OVER THE GULF OF
ALASKA...SO IT IS NOT EXPECTED TO BRING ANY SIGNIFICANTLY COLDER
AIR...WITH TEMPERATURES ON TUESDAY EXPECTED TO REACH INTO THE UPPER
40S TO AROUND 50F. WITH REASONABLY DECENT CONTINUITY AND
CONSISTENCY AMONG THE MODELS ON THIS SYSTEM...CONFIDENCE IS
RELATIVELY HIGH FOR MEASURABLE LIQUID PCPN WITH THIS SYSTEM.
ALSO...AS SWLY WINDS INCREASE IN ADVANCE OF THE APPROACHING COLD
FRONT...ELECTION DAY SHOULD BE BREEZY AND WET.
FOR THE LONGER TERM...CONFIDENCE STARTS TO QUICKLY DETERIORATE. BY
LATE TUESDAY...THE POLAR VORTEX OVER SRN QUEBEC SHOULD FINALLY KICK
OUT TO THE EAST...ALLOWING FOR SOME PROGRESSION TO THE UPPER LEVEL
PATTERN. THERE IS SOME DISAGREEMENT BETWEEN THE GFS AND ECMWF ON
HOW FAR EAST THE UPPER RIDGE WILL PENETRATE EAST OF THE MISSISSIPPI
RIVER. THE ECMWF IS MUCH MORE AMPLIFIED THAN THE GFS...WHICH WOULD
HAVE A SIGNIFICANT IMPACT ON THE TRAIN OF NORTHERN STREAM
SHORTWAVES. THESE MODEL DIFFERENCES COME INTO PLAY BY THE END OF
THE PERIOD...ESPECIALLY FOR FRIDAY AND SATURDAY. THE MORE AMPLIFIED
ECMWF SOLUTION WOULD SUGGEST BETTER CHANCES FOR PCPN THAN THE
FLATTER...BROADER UPPER LEVEL PATTERN OF THE GFS. SO...WILL NOT
MAKE ANY SIGNIFICANT CHANGES TO THE LATTER PORTIONS OF THE LONG
RANGE FORECAST...AND JUST KEEP SOME LOW POPS FOR THE NORTHERN
PORTIONS OF THE CWA FOR FRIDAY NIGHT AND SATURDAY WHEN THE ECMWF
BRINGS A SOUTHERN STREAM SHORTWAVE THROUGH THE AREA.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* WINDS LIGHT AND SLOWING TURNING FROM NNW TO NNE BUT ORD ALREADY
ON PLAN X SO NO PROBLEMS EXPECTED.
* LOWER CIGS EXPECTED TO STAY OVER ON THE INDIANA SIDE OF THE
LAKE TODAY.
LENNING
//DISCUSSION...UPDATED 12Z...
A HIGH PRESSURE RIDGE REMAINS IN PLACE FROM WESTERN QUEBEC
SOUTHWARD ACROSS RFD AND FROM THERE INTO CENTRAL AND SOUTHERN IL.
THIS WILL CREEP SLOWLY EAST TODAY WITH CONTINUED NORTHEAST FLOW
FROM LAKE MICHIGAN. SUCH A WIND COMPONENT WILL OFFER A FETCH OF
MOISTURE AND INSTABILITY SUFFICIENT ENOUGH FOR CONTINUED LAKE
EFFECT CLOUDS. THE CONVERGENCE AND FOCUS OF THESE CLOUDS SEEMS
WELL-ESTABLISHED INTO NORTHWEST INDIANA. SOME SUBTLE SHIFTING OF
THIS AXIS MAY OCCUR...BUT AT THIS POINT GIVEN ITS PLACEMENT IT
APPEARS THAT EVEN ACCOUNTING FOR THAT...THE HEART OF ANY MVFR
CIGS AND ISOLATED SHOWER ACTIVITY WOULD REMAIN EAST OF ORD AND
MDW TODAY. IN ADDITION...AN UPPER LEVEL DISTURBANCE TRANSLATING
SOUTHEAST ACROSS THE UPPER TO MID MISSISSIPPI RIVER VALLEY THIS
MORNING WILL SPREAD SOME VIRGA/LIGHT SPOTTY PRECIP OVER THE
AREA...NAMELY WEST AND SOUTH OF CHICAGO. THIS MAY EVEN INCLUDE
SOME FLURRIES AT RFD EARLY THIS MORNING. AS FOR TONIGHT...THE LOW-
LEVEL FLOW OFF OF LAKE MICHIGAN WILL VEER SOME...ALLOWING FOR THE
LIKELIHOOD OF MVFR CIGS TO MOVE BACK INTO NORTHEAST IL. TIMING ON
THIS COULD BE BE AS EARLY AS 02Z OR SO...BUT RIGHT NOW THINKING
THE LATER ROUTE. THE CLOUD DEPTHS ARE SIMILAR TONIGHT AS TO WHAT
THEY HAVE BEEN...SO AGAIN SOME SPRINKLES OR LIGHT SHOWERS THAT
STRUGGLE TO MOVE VERY FAR INLAND ARE PROBABLE. THESE CLOUDS ARE
LIKELY TO HANG IN THERE THROUGH THE MONDAY MORNING RUSH...THOUGH
CONFIDENCE IS HIGH THEY WILL BE ABOVE 1500 FT...MORE TOWARD
2500-3500 FT.
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH CONFIDENCE FOR ALL ELEMENTS.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR.
TUESDAY...SHRA LIKELY TUESDAY AFTERNOON WITH A CHC OTHERWISE
DURING THE DAY AND NIGHT. CHC OF MVFR.
WEDNESDAY-THURSDAY...VFR.
FRIDAY...SLIGHT CHC OF -RA DURING THE NIGHT.
SATURDAY...SLIGHT CHC OF -RA DURING THE DAY.
MTF
&&
.MARINE...
145 AM CST
AFTER A WEEK STRAIGHT OF NORTHERLY WINDS AND HIGHER WAVES...QUIET
WEATHER WILL PREVAIL INTO THE START OF THIS WEEK. WINDS MAY BE
VARIABLE AT TIMES OVER THE LAKE BY LATER TONIGHT THROUGH MONDAY AS A
HIGH PRESSURE RIDGE SLOWLY MOVES EAST OVER THE LAKE. WINDS WILL THEN
TURN SOUTHERLY LATE MONDAY NIGHT INTO TUESDAY AHEAD OF A LOW MOVING
QUICKLY SOUTHEAST ACROSS THE CANADIAN PRAIRIE PROVINCES. THIS
ALREADY HAS A GOOD PRESSURE AND PRESSURE TENDENCY PATTERN SIGNAL TO
RESULT IN 30 KT /OR POSSIBLY JUST HIGHER/ WINDS OVER THE NORTHERN
PORTION OF THE LAKE AND WAVES BRIEFLY UP TOWARD 10 FT. AN
ASSOCIATED COLD FRONT IS LIKELY TO MOVE THROUGH THE LAKE ON
TUESDAY NIGHT...BUT THIS FRONT SHOULD BE SLOWING AND WEAKENING AS
IT CROSSES THE LAKE. HIGH PRESSURE IS EXPECTED TO PREVAIL FOR A
DAY OR TWO AFTER THIS TIME...BEFORE SOUTHERLY FLOW INTO NEXT
WEEKEND.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1038 PM MST MON NOV 5 2012
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 112 PM MST MON NOV 5 2012
LATEST WATER VAPOR AND RUC ANALYSIS DEPICT AN UPPER LEVEL RIDGE OVER
THE WEST COAST...A SHORT WAVE TROUGH OVER SOUTHWEST CANADA WITH HIGH
CLOUDS AHEAD OF IT OVER MONTANA SOUTH INTO COLORADO AND KANSAS.
ANOTHER SHORT WAVE TROUGH WAS LOCATED OVER EASTERN OKLAHOMA AND
CONTINUES TO DEEPEN. AT THE SURFACE A WARM FRONT WAS IN PLACE
ALONG THE KS/CO BORDER NORTH INTO FAR SOUTHWEST SOUTH DAKOTA
THANKS TO THE DOWNSLOPE WINDS COMING OFF THE ROCKIES.
TONIGHT A SHORT WAVE RIDGE IN BETWEEN THE TROUGH OVER CANADA AND THE
ONE TO OUR SOUTHEAST WILL MOVE OVER THE AREA. AT THE SURFACE A
TROUGH WILL MOVE IN AHEAD OF THE UPPER LEVEL RIDGE. WINDS WILL
SHIFT WEST WITH THE TROUGH PASSAGE THEN TURN BACK NORTH BEHIND
IT. WITH A DRY ENVIRONMENT IN PLACE THE TROUGH PASSAGE WILL BE
DRY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 256 PM MST MON NOV 5 2012
FORECAST CONCERNS WILL BE THE AMOUNT OF WARMUP/FIRE WEATHER CONCERNS
WEDNESDAY THROUGH FRIDAY FOLLOWED BY COLDER TEMPERATURES/CHANCE OF
PRECIPITATION NEXT WEEKEND. SATELLITE SHOWING AN AMPLIFIED/AMPLIFYING
AND ACTIVE FLOW FROM THE PACIFIC INTO THE WESTERN ATLANTIC. SYSTEMS
TO NOTE...DEEPENING SOON TO BE STRONG SYSTEM DIGGING INTO THE
EASTERN PORTION OF THE COUNTRY WITH VERY STRONG SYSTEM
MOVING/DEVELOPING IN SOUTHERN CANADA AT THIS TIME. DRY AIR MASS
CURRENTLY RESIDES OVER THE AREA.
AT JET LEVEL...THE NAM FOLLOWED BY THE GFS WAS DOING THE BEST ON THE
VERY STRONG THAT RUNS FROM THE GULF OF ALASKA AND ON THE WEST SIDE
OF DEVELOPING EASTERN CONUS SYSTEM. AT MID LEVELS...THE GFS WAS DOING
A LITTLE BETTER THAN EVERYTHING ELSE. THE SREF AND NAM WERE DOING
BEST ON THE SURFACE WIND AND PRESSURE FIELD. THE NAM...GFS AND
CANADIAN WERE DOING BEST AT THIS TIME ON THE LOW LEVEL THERMAL
FIELD.
TUESDAY NIGHT...LITTLE CLOUD COVER AND LIGHT WINDS...ESPECIALLY IN
THE EAST...WILL ALLOW TEMPERATURES TO FALL BELOW GUIDANCE. MINS
RECENTLY HAVE FALLING WELL BELOW NWP. WENT IN THAT DIRECTION AND
CLOSER TO THE GEM 2 METER TEMPERATURES.
WEDNESDAY/WEDNESDAY NIGHT...DURING THE DAY THE SURFACE RIDGE PULLS
AWAY WITH A CHILLY START...ESPECIALLY IN THE EAST. NEWER NAM IS LESS
AGGRESSIVE WITH THE DOWNSLOPE COMPONENT. HOWEVER...WILL HAVE PLENTY
OF SUN AND WESTERLY FLOW ALOFT. KEPT TEMPERATURES ABOUT THE SAME
EXCEPT WARMING THEM UP A TOUCH. THE WIND FIELD LOOKS TO BE A LITTLE
LIGHT...ESPECIALLY IN THE EAST. AS TROUGH LINE PASSES THROUGH THE
TEMPERATURES WILL DROP WITH THEM WARMING UP AS DOWNSLOPE WINDS
INCREASE BEHIND THE TROUGH. SO WILL BE A LITTLE TRICKY.
THURSDAY...MODELS ALL OVER THE PLACE ON BOUNDARY PLACEMENT AND
TIMING AND RESULTING LOW LEVEL TEMPERATURES. CONSIDERING THE
EXPECTED FLOW ALOFT...THE MODELS MAY BE RUSHING THINGS A LITTLE BIT.
AT THIS TIME...DID A COMPROMISE BETWEEN THE WARMEST AND COOLEST
TEMPERATURES BUT DEFINITELY COULD SEE IT BEING WARMER.
THURSDAY NIGHT THROUGH MONDAY...MAJOR FEATURE OF INTEREST IS HOW
THE DEVELOPING WESTERN TROUGH WILL AFFECT THE WEATHER. THE MODELS
AND ENSEMBLES HAVE THE SAME GENERAL IDEA OF AN ELONGATED TROUGH WITH
THE STRONGEST/BEST DYNAMICS MUCH FURTHER NORTH AND SPLITTING OFF
THE WEAKER SOUTHERN END FURTHER SOUTH LEAVING OUR AREA IN THE
MIDDLE. MODELS DO DIFFER ON THE SPEED OF THE TROUGH WITH MORE
SUPPORT FOR A SLOWER ARRIVAL.
TEMPERATURES THURSDAY NIGHT WILL BE RATHER TRICKY. COLD FRONT THAT
IS EXPECTED TO MOVE THROUGH SOMETIME ON THURSDAY IS EXPECTED TO
RETURN NORTH AS A WARM FRONT THURSDAY NIGHT INTO FRIDAY. MODEL IN
GENERAL AGREEMENT ON FRIDAY WITH THE FRONT NEAR OR NORTH OF THE
FORECAST AREA BY LATE IN THE DAY. OVER THE SOUTHERN HALF TO TWO
THIRDS...MODELS AGREE ON VERY WARM 850 MB TEMPERATURES. WILL HAVE
DEEP SOUTHWEST FLOW ALOFT. AT THIS TIME DO NOT EXPECT THICK CLOUD
COVER. AS A RESULT OF THAT AND COLLABORATION...WARMED UP MAXES.
THIS WARM UP STILL MAY NOT BE ENOUGH.
FRIDAY NIGHT INTO SATURDAY THE FRONT COMES BACK SOUTH AS A COLD
FRONT. SOME DISCREPANCY ON TIMING BUT THERE LOOKS TO BE A THICKENING
CLOUD DECK AND DEVELOPING PRECIPITATION THROUGH THE DAY. SO LEFT
THE INHERITED INIT ALONE. VERY COLD TEMPERATURES FOLLOWING
ESPECIALLY FOR SATURDAY NIGHT INTO SUNDAY NIGHT. INIT GRIDS LOOK
FINE BUT DID MAKE A MINOR ADJUSTMENT DOWN.
SATURDAY...ESPECIALLY FROM THE AFTERNOON...INTO SUNDAY LOOKS TO BE
OUR CHANCE FOR PRECIPITATION. ONLY CONCERN NOW IS IF THE SLOWER
SOLUTIONS PREVAIL...THE PRECIPITATION COULD START LATER IN THE DAY
ON SATURDAY AND CONTINUE THROUGH MORE OF SUNDAY. DESPITE THE BRUNT
OF THE LIFT BEING FURTHER NORTH...RIGHT REAR QUADRANT OF JET...VERY
STRONG PV ANOMALY...AND STRONG CO-LOCATED MESOSCALE FORCING LOCATED
WITH FAVORABLE THETA-E LAPSE RATES...DO SUPPORT LIGHT PRECIPITATION
OCCURRING. THINK WE WILL GET SOMETHING JUST NOT SURE HOW MUCH. AM
CONCERNED AND WILL HAVE TO BE WATCHED CAREFULLY IN UPCOMING
FORECASTS OF BANDED PRECIPITATION DEVELOPING OVER THE AREA. KEPT
THE PHASE RAIN SATURDAY AFTERNOON AND SWITCHED IT OVER TO ALL SNOW
SATURDAY NIGHT. DEPENDING ON HOW LONG THE PRECIPITATION LINGERS
INTO SUNDAY...COULD BE ALL SNOW OR A RAIN AND SNOW MIXTURE. FOR THE
PRECIPITATION KEPT WHAT THE INIT GRID PRODUCED. REMAINDER OF THE
FORECAST IS DRY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1034 PM MST MON NOV 5 2012
WINDS WILL SHIFT TO THE NORTHWEST OVERNIGHT AS A SURFACE TROUGH
MOVES EAST. CONDITIONS WILL BE VFR AS A FEW MID LEVEL AND
SCATTERED TO BROKEN MID LEVEL CLOUDS COTNINUE. WINDS WILL BECOME
LIGHT AND VARIABLE AGAIN TUESDAY NIGHT AS HIGH PRESSURE SETTLES
INTO THE AREA.
&&
.FIRE WEATHER...
ISSUED AT 256 PM MST MON NOV 5 2012
ON WEDNESDAY...RELATIVE HUMIDITIES WILL BECOME LOW. HOWEVER THE WIND
FIELD LOOKS TO BE TOO LIGHT SO DO NOT EXPECT ANY FIRE WEATHER
HIGHLIGHTS.
ON FRIDAY...THIS DAY WILL HAVE TO BE WATCHED CAREFULLY. RELATIVE
HUMIDITIES BE SOUTH OF THE WARM FRONT. WINDS WILL ALSO PICK UP IN
THE SAME AREA. IF WARM FRONT IS FASTER MOVING NORTH AND THE WINDS
END UP STRONGER...THERE MAY BE A NEED FOR A FIRE WEATHER HIGHLIGHT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...JTL
LONG TERM...BULLER
AVIATION...FS
FIRE WEATHER...BULLER
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1040 PM CST MON NOV 5 2012
.UPDATE...
SCATTERED SHOWERS AND THUNDERSTORMS CONTINUE OVER THE COASTAL
WATERS...WITH ACTIVITY ENDED OVER LAND. HAVE GONE AHEAD AND
CANCELLED WW 674...WITH WW 673 HAVING EXPIRED AT 9 PM. MADE SOME
ADJUSTMENTS TO POPS/WX TO REFLECT CONVECTIVE TRENDS. DESPITE
PASSAGE OF FRONTAL BOUNDARY THIS EVENING...WINDS REMAIN VERY LT
ACRS THE AREA. BOTH 03Z RUC AND 00Z NAM SHOW THE POSSIBILITY OF
FOG OVER ERN ZONES TONIGHT...AND GIVEN THE COMBINATION OF LT
WINDS...CLEARING SKIES AND SFC MOISTURE...WENT AHEAD AND INCLUDED
PATCHY FOG MAINLY FM POE TO LCH EASTWARD.
FOR THE MARINE ZONES...ADDED EXERCISE CAUTION WITH NLY WINDS
EXPECTED TO STRENGTHEN TO 15-20 KT TONIGHT.
UPDATED PRODUCTS HAVE BEEN SENT. 24
&&
.PREV DISCUSSION... /ISSUED 717 PM CST MON NOV 5 2012/
UPDATE...
REMOVED OUR INTERIOR SE TX COUNTIES FM WATCH 673...WITH CONVECTION
CONTINUING TO SHIFT SOUTH AND EAST. UPDATED GRIDS AND PRODUCTS. 24
PREV DISCUSSION... /ISSUED 557 PM CST MON NOV 5 2012/
UPDATE...
A QUICK UPDATE TO ADD SEVERE TSTM WATCH 674 IN EFFECT UNTIL 1 AM FOR
SRN LA AND THE ADJACENT COASTAL WATERS. THIS IS IN ADDITION TO
WATCH 673...RESULTING IN MOST OF THE AREA...EXCEPT FOR THE EXTREME
NRN TIER OF LA PARISHES...UNDER A WATCH. SCT SEVERE TSTMS CONTINUE
TO DEVELOP AND MOVE ACRS SRN LA...INCLUDING A RATHER POTENT STORM
THAT JUST MOVED OVER THE OFFICE...DROPPING PEA TO QUARTER SIZE
HAIL AND PRODUCING A WIND GUST TO 60 KT! 24
PREV DISCUSSION... /ISSUED 430 PM CST MON NOV 5 2012/
DISCUSSION...
LATEST UPPER AIR ANALYSIS/WATER VAPOR IMAGERY SHOWED A VIGOROUS
MID/UPPER LOW DIVING SOUTHEAST INTO THE LOWER MS RIVER
VALLEY...WITH A SECONDARY SHORTWAVE JUST ENTERING THE NORTHERN
PLAINS. LATEST SFC ANALYSIS INDICATED CDFNT WAS JUST NORTH/WEST
OF A SHREVEPORT LOUISIANA TO COLLEGE STATION TEXAS LINE...EXTENDING
SOUTHWEST OF A SFC LOW OVER SOUTHWEST ARKANSAS.
ISOLATED TO SCATTERED CONVECTION HAS DEVELOPED LATE THIS
AFTERNOON AS ROBUST SYNOPTIC LIFT ACTS UPON THE MOIST UNSTABLE
WEDGE IN PLACE OVER TE AREA. THIS ACTIVITY IS EXPECTED TO CONTINUE
INTO THE EVENING HOURS ALONG AND AHEAD OF THE SOUTHWARD MOVING
FRONT. A SVR TSTM WATCH IS IN EFFECT FOR EAST TX AND SW LA UNTIL 9
PM...AND THIS LOOKS REASONABLE AS FCST SOUNDINGS ARE SUPPORTIVE OF
A HAIL/WIND THREAT.
THE CDFNT IS PROGGED TO REACH THE COAST BY EARLY/MID EVENING...AND
CONTINUE SOUTHWARD THROUGH THE COASTAL WATERS AS THE UPPER LOW
PIVOTS EAST THROUGH NORTHERN MS/AL. COOLER AND DRIER AIR IS
EXPECTED IN THE WAKE OF THE FRONT...WITH LOW TEMPERATURES TUE
MORNING A GOOD 10 DEGREES OR SO COOLER THAN THEY WERE TODAY.
THE CAA IS FCST TO BECOME A BIT MORE NEUTRAL BY TOMORROW...AND
WILL BE FURTHER OFFSET BY GOOD DIURNAL HEATING. A SECONDARY
SURGE...OR REINFORCING FRONT...IS EXPECTED TO ACCOMPANY THE
UPSTREAM SHORTWAVE TUESDAY NIGHT INTO WED...THOUGH IT WILL BE
SOMETHING OF A GLANCING BLOW AS THE CORE OF COLDEST AIR WILL PASS
TO OUR EAST.
NO REAL CHANGES MADE TO THE EXTENDED FCST...AS GLOBAL MODELS
CONCUR WITH THE NORTHWESTERLY FLOW ALOFT TRANSITIONING TO UPPER
RIDGING THURSDAY...WHICH THEN GIVES WAY TO A DEEP AND
STRENGTHENING LOW TO MID LEVEL SOUTHERLY FETCH INTO THE WEEKEND
AS A LARGE UPPER TROF CARVES OUT OVER THE WESTERN CONUS. THEY
CONTINUE TO DIFFER A BIT ON THE TIMING OF THE NEXT FRONT...WITH
THE ECMWF A LITTLE SLOWER THAN THE GFS. HIGHEST RAIN CHANCES
PEGGED FOR SUNDAY NIGHT INTO MONDAY TIME PERIOD STILL LOOK GOOD.
MARINE...
SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE THE REST OF THIS
AFTERNOON INTO THIS EVENING AS A VIGOROUS UPPER LEVEL SYSTEM DIVES
SOUTHEAST THROUGH THE LOWER MISSISSIPPI RIVER VALLEY. THIS SYSTEM
WILL DRIVE A COLD FRONT THROUGH THE COASTAL WATERS TONIGHT...WITH
GUSTY NORTH WINDS AND BUILDING SEAS EXPECTED AFTER MIDNIGHT IN
ITS WAKE. AT THIS TIME...WITH THE SEVERE THUNDERSTORM WATCH IN
EFFECT...AND CONDITIONS LOOKING BORDERLINE BETWEEN SCEC AND
SCA...I HAVE HELD OFF ON ANY MARINE HEADLINES OR ADVISORIES. WINDS
AND SEAS WILL BEGIN SUBSIDE ON TUESDAY...BUT OFFSHORE FLOW WILL
PREVAIL THROUGH WEDNESDAY NIGHT. SOUTHERLY WINDS ARE EXPECTED TO
RETURN ON THURSDAY...AND GRADUALLY STRENGTHEN INTO THE WEEKEND.
13
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 52 69 47 73 / 30 10 0 0
KBPT 53 73 50 76 / 30 10 0 0
KAEX 48 67 44 70 / 20 10 0 0
KLFT 53 69 46 71 / 50 10 0 0
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...SMALL CRAFT EXERCISE CAUTION UNTIL 10 AM CST TUESDAY FOR COASTAL
WATERS FROM CAMERON LA TO HIGH ISLAND TX OUT 20 NM-COASTAL
WATERS FROM INTRACOASTAL CITY TO CAMERON LA OUT 20 NM-
COASTAL WATERS FROM LOWER ATCHAFALAYA RIVER TO INTRACOASTAL
CITY LA OUT 20 NM-WATERS FROM INTRACOASTAL CITY TO CAMERON
LA FROM 20 TO 60 NM-WATERS FROM CAMERON LA TO HIGH ISLAND
TX FROM 20 TO 60 NM-WATERS FROM LOWER ATCHAFALAYA RIVER TO
INTRACOASTAL CITY LA FROM 20 TO 60 NM.
&&
$$
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1135 PM CST MON NOV 5 2012
.DISCUSSION...
STILL A SMALL CHANCE OF SPRINKLES MOVING THROUGH THE REGION...
GENERALLY ALONG AND NORTH OF I80 TONIGHT. AMOUNTS STILL APPEAR TO
BE VERY LIGHT WITH MOSTLY TRACE AMOUNTS.
ALSO STILL LOOKS INCREASINGLY WINDY THROUGH THE DAY TUESDAY...WITH
WIND SPEEDS NEAR ADVISORY CRITERIA IN NORTHEAST NEBRASKA.
DEWALD
&&
.AVIATION...06Z TAFS FOR KOMA...KLNK AND KOFK. MVFR CONDITIONS
PERSIST AT KOMA...AND LIKELY WILL UNTIL 10-12Z BEFORE LOW CLOUDS
SCATTER OUT. OTHERWISE...VFR CONDITIONS PREVAIL AT BOTH KLNK/KOFK.
SOUTH SOUTHWEST WINDS AHEAD OF THE APPROACHING FRONT...SWITCHING
TO NORTHWEST ONCE THE FRONT ARRIVES...ARRIVING AT KOFK BY
11Z...AND KOMA/KLNK BY 13-14Z. SUSTAINED WIND SPEEDS INCREASE TO
20 TO 25 KNOTS SUSTAINED...WITH GUSTS UP TO 30 TO 35 KNOTS...BUT
SHOULD DIMINISH ONCE THE SUN GOES DOWN BY 07/00Z.
DEWALD
&&
.PREV DISCUSSION... /ISSUED 633 PM CST MON NOV 5 2012/
DISCUSSION...
TWEAKED THE FORECAST JUST SLIGHTLY TO BRING PRECIP CHANCES INTO
NORTHEAST NEBRASKA A FEW HOURS EARLIER...BASED ON RADAR ECHOS
MOVING OUT OF SOUTH DAKOTA AND NORTH CENTRAL NEBRASKA. ALSO
TRIMMED THE BACK EDGE OF THE PRECIP JUST A BIT...AND BROUGHT IT
JUST A LITTLE BIT FURTHER SOUTH. EITHER WAY...IT WILL LIKELY BE
VERY VERY LIGHT...PERHAPS ONLY JUST TRACE AMOUNTS.
ALSO TWEAKED THE WINDS UP A COUPLE OF KNOTS ON TUESDAY IN
NORTHEAST NEBRASKA. WINDS MAY BE JUST SHY OF WIND ADVISORY
CRITERIA IN NORTHEAST NEBRASKA AROUND 30 MPH SUSTAINED.
DEWALD
PREV DISCUSSION... /ISSUED 318 PM CST MON NOV 5 2012/
SHORT TERM...TONIGHT THROUGH THURSDAY.
MAIN FORECAST CONCERN IS SMALL CHANCE FOR SHOWERS IN OUR
NORTHEAST OVERNIGHT.
LATEST WATER VAPOR IMAGERY AND RAP 500MB ANALYSIS SHOW THE REGION IN
NORTHWESTERLY FLOW ALOFT WITH SHORTWAVE ENERGY QUICKLY DROPPING
THROUGH THE SOUTHERN CANADIAN PRAIRIE PROVINCES. ASSOCIATED SFC LOW
PRESSURE AREA CONTINUES TO QUICKLY MOVE SOUTHEAST AHEAD OF THIS
UPPER FEATURE WITH WIDESPREAD SHOWERS ACROSS NORTH DAKOTA. THESE
FEATURES WILL CONTINUE THEIR SOUTHWARD PROGRESSION AND SHOULD BRUSH
THE NORTHEASTERN COUNTIES OVERNIGHT...MAINLY AFTER 06Z. HAVE ADDED A
SMALL CHANCE FOR SHOWERS AS MOISTURE PROFILES ARE SLOW TO SATURATE
LOWER LEVELS. IN ADDITION...ASSOCIATED SFC COLD FRONT WILL PUSH
THROUGH THE FORECAST AREA TUESDAY MORNING. GOOD MOMENTUM TRANSFER
SHOULD ALLOW GUSTY CONDITIONS INTO TUESDAY AFTERNOON BEHIND THE
FRONT. HIGH TEMPERATURES SHOULD ONLY TOP OUT IN THE LOWER 50S
ACROSS THE NORTHEASTERN CWA WITH UPPER 50S IN THE SOUTHWEST. SFC
HIGH PRESSURE QUICKLY BUILDS IN WEDNESDAY MORNING BRINGING CLEAR
AND CALM CONDITIONS. A GRADUAL WARMING TREND WEDNESDAY INTO
THURSDAY IS EXPECTED AS A WESTERN RIDGE BUILDS EAST OVER THE AREA
AND RETURN FLOW DEVELOPS AROUND SFC HIGH PRESSURE.
KERN
LONG TERM...THURSDAY NIGHT THROUGH MONDAY.
LOOKS LIKE SOME ACTIVE WEATHER FOR THE WEEKEND WITH BIG SWINGS IN
TEMPERATURES.
THE EC/GFS/GEFS/CANADIAN ARE ALL IN FAIRLY GOOD AGREEMENT...WITH
SOME TYPICALLY TIMING AND STRENGTH DIFFERENCES. THE FORECAST AREA
WILL BE IN THE WARM SECTOR THURSDAY NIGHT WITH AN INVERTED TROF
SETTLING INTO NORTHEAST NEBRASKA. THE GULF IS OPEN WITH H85 FLOW
FROM TEXAS THROUGH THE PLAINS WITH THE DRY SLOT HEADING ACROSS NORTH
CENTRAL KANSAS BY 12Z FRIDAY. THE SURFACE LOW INITIALLY OVER THE
CENTRAL ROCKIES TRACKS NORTHEAST ALONG THE FRONT AND BY 18Z SATURDAY
IS CENTERED SOMEWHERE BETWEEN EASTERN SOUTH DAKOTA/EASTERN NEBRASKA
(GFS/EC/GEFS) OR MINNESOTA (CANADIAN). THE BULK OF THE
PRECIPITATION WILL INITIALLY BE AHEAD OF...NORTH...AND TO THE WEST
OF THE FORECAST AREA. SATURDAY NIGHT LOOKS TO BE THE BEST CHANCE
FOR PRECIPITATION...ALTHOUGH THERE WILL BE LIFT/WAA DURING THE DAY
SATURDAY. THE GFS HAS A SURGE OF HIGHER DEWPOINTS NEAR THE MISSOURI
RIVER AND THEN LIFTING NORTH AND SHIFTING QUICKLY EAST. THE EC IS
SLOWER WITH THE DEEP MOISTURE AND HOLDS ON TO THE HIGH 10 TO 12DEG C
H85 DEWPOINTS. COMBINED WITH THE LIFT WITH THIS DYNAMIC SYSTEM THESE
DIFFERENCES ACCOUNT FOR THE DIFFERENCES IN RESULTANT QPF WITH HIGHER
PRECIPITATION AMOUNTS WITH THE EC.
TEMPERATURES FRIDAY AND SATURDAY WILL BE IN THE 60S AND 70S AND
MUCH COLDER FOR SUNDAY AND MONDAY WITH HIGHS IN THE 30S AND 40S.
FOR NOW HAVE SOME CHANCE POPS SATURDAY AFTERNOON AND LIKELY POPS
SATURDAY NIGHT AND DEPENDING ON IF THE SYSTEM SLOWS DOWN...SOME POPS
INTO SUNDAY. WITH INSTABILITY AHEAD OF THE FRONT WILL INCLUDE
THUNDER. THERE COULD BE A MIX IN THE NORTHEAST AS COLDER AIR WORKS
INTO THE SYSTEM IN NORTHEAST NEBRASKA. SHOULD THERE BE LINGERING
PRECIPITATION SUNDAY...THERE COULD BE A MIX OR MINOR
ACCUMULATIONS SUNDAY.
ZAPOTOCNY
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1124 PM CST MON NOV 5 2012
.UPDATE...
.AVIATION...
VFR IS EXPECTED ALL AREAS OVERNIGHT THROUGH TUESDAY EVENING.
A COLD FRONT WILL MOVE THROUGH OVERNIGHT. WINDS ACROSS NCNTL NEB
EAST OF HIGHWAY 83 INCREASE TO 32025G35KT TUESDAY MORNING.
LIGHT RAIN SHOWERS HAVE DEVELOPED ALONG AND BEHIND THE FRONT THIS
EVENING. VFR IS EXPECTED BENEATH THOSE RADAR RETURNS.
&&
.PREV DISCUSSION... /ISSUED 833 PM CST MON NOV 5 2012/
UPDATE...
ISOLATED SHOWERS CONTINUE TO DEVELOP ACROSS WRN AND CNTL SD. IT
LOOKS LIKE THERE IS ENOUGH MOISTURE ALOFT FOR SOME RAIN AT THE SFC
BASED ON 00Z SOUNDINGS. OBSERVED STORM MOTION SHOULD CARRY THE
LIGHT RAIN THRU NCNTL NEB OVERNIGHT. ALSO RAISED TEMPS A CATEGORY
AS FAIRLY DENSE MID AND UPPER LEVEL CLOUDS SHOULD CONTINUE OVERNIGHT.
PREV DISCUSSION... /ISSUED 547 PM CST MON NOV 5 2012/
UPDATE...
AVIATION...
VFR IS EXPECTED MOST AREAS TONIGHT AND TUESDAY.
A COLD FRONT WILL MOVE THROUGH TONIGHT WITH WINDS INCREASING AFTER
15Z TO 32025G35KT ACROSS NCNTL NEB EAST OF HIGHWAY 83.
SPRINKLES HAVE DEVELOPED AHEAD OF THE FRONT THIS EVENING. VFR IS
EXPECTED BENEATH THOSE RADAR RETURNS. ALSO...THE BANK OF MVFR CIGS
ACROSS NCNTL NEB GETS SHOVED EAST AS THE COLD FRONT APPROACHES
LATE TONIGHT...09Z- 12Z. NOTE THE RUC SUGGESTS SOME POTENTIAL FOR
MVFR CIGS LATE TONIGHT WITH THE COLD FRONT. FOR NOW PLAN ON VFR.
BEST GUESS ON MVFR CAN BE MADE AS THE FRONT GETS CLOSER THIS
EVENING.
PREV DISCUSSION... /ISSUED 317 PM CST MON NOV 5 2012/
SYNOPSIS...ANALYSIS OF THE 19Z MSL DATA SHOWED A FRONTAL WAVE IN
SOUTHERN SASKATCHEWAN. ASSOCIATED WITH THE SURFACE LOW...WATER
VAPOR IMAGERY WAS SHOWING A POTENTIAL VORTICITY ANOMALY NEAR THE
BOUNDARY BETWEEN EAST CENTRAL ALBERTA AND WEST CENTRAL
SASKATCHEWAN. A SURFACE FRONT HAD MOVED OUT OF SOUTHERN ALBERTA
AND SASKATCHEWAN INTO NORTHERN MONTANA. THERE WAS ALSO AN
ABUNDANCE OF JETSTREAM-RELATED CIRRUS/CIRROSTRATUS STREAMING OVER
THE MONTANA-WYOMING ROCKIES ON THE NORTHWEST FLOW. VISIBLE IMAGERY
INDICATED SOME CUMULIFORM CLOUDINESS FROM CENTRAL TO SOUTHWEST
NEBRASKA.
SHORT TERM...A FRONT COMING OUT OF NORTHERN MONTANA WILL COME
THROUGH NEBRASKA LATE TONIGHT TO EARLY TUESDAY AND BRING SOME
PATCHY CLOUDINESS. THEN...RETURN FLOW WILL BRING THE FRONT BACK
TOWARD THE EAST AGAIN TUESDAY NIGHT AND...WITH IT...SOME
CLOUDINESS. TEMPERATURES TONIGHT WILL BE HELD TO THE MID TO UPPER
30S TONIGHT BY THE AREAS OF CLOUDINESS. WITH MORE SUNSHINE THAN
TODAY AND BREEZIER CONDITIONS...TEMPERATURES TUESDAY WILL BE
SOMEWHAT WARMER THAN TODAY. CLEARING SKY AND LIGHT WIND WILL LET
TEMPERATURES FALL INTO THE 20S OVER THE AREA TUESDAY NIGHT.
LONG TERM...A SIGNIFICANT LONG WAVE TROUGH IS STILL PROGGED TO
PROGRESS EAST ACROSS THE THE PLAINS SATURDAY INTO SUNDAY. AHEAD
OF THIS FEATURE...MILD WEATHER WILL CONTINUE...WITH HIGHS ABOVE
NORMAL WEDNESDAY THROUGH FRIDAY. A DRASTIC CHANGE IN THE WEATHER
WILL OCCUR SATURDAY...AS A STRONG COLD FRONT PLOWS SOUTHEAST
ACROSS NEBRASKA. GUSTY NORTHWEST WINDS AND FALLING TEMPERATURES
CAN BE EXPECTED BEHIND THE FRONT SATURDAY AFTERNOON...WITH LIGHT
RAIN OR LIGHT SNOW DEVELOPING WITHIN AREA OF STRONG FRONTOGENESIS
BEHIND THE FRONT. LIGHT SNOW WILL LINGER INTO SATURDAY NIGHT...AND
SHOULD END BY SUNDAY MORNING AS HIGH PRESSURE BEGINS TO BUILD INTO
THE AREA. IT IS STILL TOO EARLY TO KNOW EXACTLY HOW MUCH SNOW WILL
ACCUMULATE...BUT ALL INDICATIONS ARE THAT AMOUNTS SHOULD BE
LIGHT...WITH PERHAPS AN INCH OR TWO FALLING ACROSS NORTHWEST
NEBRASKA. WILL CONTINUE TO MONITOR...AND UPDATE FORECASTS AS THE
STORM SYSTEM GETS CLOSER. VERY CHILLY CONDITIONS ARE EXPECTED
SUNDAY...WITH MANY AREAS STRUGGLING TO REACH THE FREEZING MARK.
SOME TEMPERATURE RECOVERY IS EXPECTED MONDAY AS THE COLDEST AIR
MOVES EAST OF THE AREA.
AVIATION... NO SIGNIFICANT RESTRICTIVE WEATHER IS EXPECTED TONIGHT
THROUGH TUESDAY. CEILINGS...IF ANY...WILL BE AT OR ABOVE 5000
FEET AGL. WIND IS EXPECTED TO INCREASE TUESDAY. IN NORTH CENTRAL
NEBRASKA...NEAR ONL...BUB...BBW AND ANW...THE WIND IS EXPECTED TO
BE 310-330 INCREASING TO 20-23G26-30 BY 18Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM/EXTENDED...MASEK
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1148 PM CST MON NOV 5 2012
.SHORT TERM...
928 PM CST MON NOV 5 2012
GOES WATER VAPOR IMAGERY UPSTREAM OVER SOUTHERN CANADA SHOWING TWO
IMPULSES WITH A NICE SIGNAL OF DARKENING JUST WEST OF LAKE
WINNIPEG AT 02Z. THIS DARKENING WAS ASSOCIATED WITH A RAP-ANALYZED
TROPOPAUSE FOLD DOWN TO 600 MB. SOME ADDITIONAL DARKENING
ASSOCIATED WITH THE INITIAL VORTICITY ADVECTION IN THE TROUGH IN
ERN SD AS WELL. THIS LEAD TROUGH IS CAUSING SOME ELEVATED ECHO
OVER MN/SD WITH VERY LITTLE PRECIPITATION BEING OBSERVED.
THE LOCAL AREA WILL TAKE A DIRECT HIT FROM THE SECOND STRONG
SHORTWAVE TROUGH NEAR LAKE WINNIPEG BASED ON FORECAST MODEL CONSENSUS.
THIS HAS DEVELOPED A MORE N-S BAND OF ECHO ALONG THE ERN ND BORDER
EXTENDING NORTH INTO MANITOBA WITH A FEW HUNDREDTHS OF PRECIPITATION
PER HOUR BEING REPORTED. QG ANALYSIS TAKES THE LIFT FROM THESE
DYNAMICS RIGHT ACROSS THE FORECAST AREA IN THE 06.00 AND 05.18
NAM...LATEST RAP FORECASTS...AND 05.18 GFS. HAVE INCREASED
PRECIPITATION CHANCES TO 80 PERCENT IN MOST AREAS.
SOME QUESTION ON THE PRECIPITATION TYPE AS THE CLOUDS HAVE HELD
FIRM OVER SERN MN...AND SLIPPED A BIT EAST INTO NW WI.
OTHERWISE...TEMPERATURES WERE REALLY COOLING IN MOST OF EXTREME
NERN IA...SWRN AND CENTRAL WI UNDER CLEAR SKIES. ONCE THE CLOUD COMES
OVER...EVEN THOUGH IT IS 8KFT...TEMPERATURES WARM RAPIDLY 3-4F.
FOR CENTRAL WI INTO SWRN WI...WITH THICKER CLOUDS EXPECTED JUST
PRIOR TO PRECIPITATION ONSET...TEMPERATURES AND WETBULB
TEMPERATURES WOULD SEEM TO SUPPORT A BIT OF SNOW ACCUMULATION /IN
ADDITION TO I-94/NORTHEAST ACCUM AREA FROM PREV FORECAST/. WITH WARM SOILS
OF 40F OR MORE AT 2 INCHES...STILL THINK ACCUMULATION DIFFICULT.
BUT...WHERE IT IS THE COLDEST TONIGHT WILL FAVOR SOME...GENERALLY
1/2 INCH OR LESS. 06.00Z NAM SNOW DEPTH...WHICH MODELS THE LAND
SURFACE HEAT FLUXES...PLACED 0.3 INCHES OF SNOW ACCUM IN THAT
REGION...RICHLAND/ERN VERNON COUNTY/MONROE AREA.
AN OUTSIDE CHANCE OF VERY BRIEF FZRA IS POSSIBLE FOR ANY SITE
REMAINING 32F OR BELOW...AND MAINLY JUST EAST OF THE MISS RIVER
WHERE THE TOP OF THE INVERSION WOULD BE WARM ENOUGH TO MELT
INCOMING ICE. HAVE NOT ADDED THIS TO THE FORECAST BUT WE WILL
MONITOR AS IT APPROACHES LATER TONIGHT. IT MAY NEED A SPECIAL
WEATHER STATEMENT. A CHANGE TO SNOW WOULD QUICKLY RESULT AS THE
THERMAL PROFILE GOES TO THE WET-BULB NEAR 0C. FORECAST UPDATES ARE
OUT.
.LONG TERM...THURSDAY NIGHT THROUGH MONDAY
304 PM CST MON NOV 5 2012
AN ACTIVE PERIOD IS ON TAP FOR THE WEEKEND INTO EARLY NEXT WEEK AS
BROAD UPPER LEVEL TROUGHING PROPAGATES EAST ACROSS THE ROCKIES ON
INTO THE CENTRAL US AND GREAT LAKES REGION.
THE QUESTION TO START THE EXTENDED PERIOD IS WITH HOW FAR SOUTH A
COLD FRONT MAKES IT ON FRIDAY BEFORE IT STALLS OUT AND TRANSITIONS
TO A WARM FRONT. THE 05.12Z ECMWF IS TRENDING TOWARD WHAT THE GFS
HAS ADVERTISED THE PAST FEW DAYS WITH A MORE SOUTHERN SOLUTION. BY
00Z SATURDAY...THE FRONT WILL START NEAR A SURFACE LOW IN EASTERN
COLORADO AND RUN EAST THROUGH NORTHWEST IOWA AND CENTRAL
WISCONSIN. THE 05.12Z GFS SHOWS SOME PRECIPITATION DEVELOPING
ALONG THIS FRONT FRIDAY NIGHT AS THE LOW LEVEL JET KICKS IN AND
NOSES UP INTO THE REGION WHILE THE 05.12Z ECMWF/GEM KEEP IT DRY
WITH THE FOCUS A BIT FURTHER NORTH. A LOW PRESSURE SYSTEM WILL
THEN DEVELOP IN THE LEE OF THE ROCKIES ALONG THIS FRONT AND TRACK
NORTHEAST ALONG THE FRONT AND DEEPEN INTO MINNESOTA ON
SATURDAY/SATURDAY NIGHT WITH THE 05.12Z GFS/ECMWF IN DECENT
AGREEMENT ON THIS SCENARIO. THIS TRACK WILL LEAD TO SATURDAY BEING
THE WARMEST DAY OF THE WEEK WITH TEMPERATURES GETTING INTO THE
60S. AS A RESULT OF THIS RELATIVELY WARM AND MOIST AIR MASS
GETTING IN...THERE APPEARS TO BE SOME WEAK INSTABILITY THAT
DEVELOPS AHEAD OF THE FRONT SO THERE COULD BE A FEW THUNDERSTORMS
THAT DEVELOP THOUGH TIMING DOES NOT LOOK FAVORABLE FOR ANYTHING
SEVERE.
THE FRONT THEN SLOWLY TRACKS TO THE EAST ON SUNDAY WITH
PRECIPITATION LIKELY FORMING ALONG AND BEHIND IT. WITH STRONG LOW
LEVEL COLD AIR ADVECTION BEHIND THE FRONT...IT APPEARS THAT
TEMPERATURES WILL BE ABLE TO COOL ENOUGH FOR THE RAIN TO
TRANSITION TO SNOW FOR A PERIOD. THEN...THERE IS THEN CONTINUED
GOOD AGREEMENT BETWEEN THE 05.12Z GFS/ECMWF FOR THE BELLY OF THE
MID LEVEL TROUGH TO BECOME NEGATIVELY TILTED ON MONDAY WITH A
DEEPENING SURFACE LOW RUNNING UP THE COLD FRONT THROUGH CHICAGO.
THERMAL PROFILES WOULD BE COLD ENOUGH FOR THE PRECIPITATION TYPE
TO BE ALL SNOW...SO THE TRENDS WITH THIS SYSTEM WILL HAVE TO BE
MONITORED SINCE THE TRACK WOULD DICTATE WHERE THE HEAVIEST SNOW
WOULD FALL. RIGHT NOW...THE 05.12Z GFS IS FASTER WITH THE SURFACE
LOW NEAR SOUTHERN LAKE MICHIGAN BY 18Z MONDAY WHILE THE 05.12Z
ECMWF GETS IT THERE AROUND 6Z TUESDAY.
&&
.AVIATION...THROUGH 06Z WEDNESDAY
1147 PM CST MON NOV 5 2012
HAVE ADJUSTED LATEST TAFS TO INCLUDE IFR CONDITIONS AT KRST FOR
INCOMING WEATHER SYSTEM. THIS WEATHER SYSTEM IS PRODUCING
PRECIPITATION ACROSS NWRN MN WITH ITS LEADING EDGE APPROACHING
CENTRAL MN AT THIS TIME. CONFIDENCE IS HIGH ON PRECIPITATION
AFFECTING BOTH SITES FOR 4-5 HOURS. WITH COLDER AIR IN PLACE
AT KLSE...SNOW IS A POSSIBILITY...MIXED WITH RAIN. HAVE INCLUDED
SNRA AT KLSE WITH MVFR CIGS/VSBYS. PRECIPITATION SHOULD BE
PROGRESSIVE WITH IMPROVING CONDITIONS TO VFR OR HIGHER MVFR AS
AFTERNOON PROGRESSES. A LARGE CLOUD SHIELD WILL THEN SPREAD IN
FROM THE NORTH TUESDAY NIGHT WITH MVFR CONDITIONS EXPECTED AT BOTH
SITES.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
304 PM CST MON NOV 5 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM...HALBACH
AVIATION...BAUMGARDT
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
1007 AM EST Tue Nov 6 2012
.NEAR TERM [Through Tonight]...
The 12z CONUS NAM/Regional RAP analysis depicted a highly
amplified pattern across the country with the western half
dominated by deep layer ridging, and a broad trough across the
east. Embedded within the eastern U.S. trough were several
disturbances, most notably the potent shortwave centered over the
Southeast. It was this disturbance that initiated widespread rain
and isolated thunderstorms overnight. As of 14z the shortwave had
made enough eastward progress to push the surface front through
the area. Thus, land areas across our CWA are rain free, with
only isolated showers remaining well offshore. The main concern
this morning has to do with timing the dissipation of fog that
developed in the clear region between the passing front and
advancing low ceilings, as well as timing the dissipation of the
ceilings themselves. The current thinking is that the remaining fog
will dissipate within the next hour, while the ceilings will
slowly scatter through the morning, making little eastward
progress. The trend in ceilings will have to be monitored closely
as any prolonged ceilings could have a substantial impact on
afternoon high temperatures. For now, expect a north to south
temperature gradient with high in the lower 60s across southern GA
and AL, up to near 70 degrees across coastal portions of North
Florida.
Overnight, the focus shifts back to the upper levels as another
piece of energy dives south through the Mississippi Valley, then
into the Southeast. There may be just enough moisture with this
shortwave to generate some light showers overnight, more likely
across AL and GA rather than FL. There may also be a fog/low
ceiling mixture across AL and GA, possibly spilling into inland
north Florida as well. Overnight lows are expected to fall into
the lower to middle 40s area wide.
&&
.SHORT TERM [Wednesday Through Thursday]...
The axis of the upper trough will swing to our east on Thursday
with deep layer ridging approaching the CWA from the west. Temps
on Wednesday and Thursday will only climb to the mid to upper
60s. The coldest temps are forecast for Wednesday night where all
inland areas should see upper 30s with mid 40s near the coast by
daybreak Thursday.
&&
.LONG TERM [Thursday Night through next Monday]...
Deep layer ridging will continue to build in from the west and by
late in the week temperatures are expected to moderate back to
near/above normal levels. Dry conditions are expected through next
weekend before rain chances increase ahead of a cold front early
next week.
&&
.AVIATION [Beginning 14Z Tuesday]...
MVFR ceilings on the backside of a passing front will slowly
scatter through the morning. Expect these ceilings to at least
rise to VFR levels by around 18z. A low ceiling/fog mix is
possible once again tomorrow morning, however, this threat will be
looked at more closely when the latest data arrives before the
next full TAF issuance.
&&
.MARINE...
Winds and seas will increase today behind a cold front that passed
overnight. Cautionary level winds will develop today and continue
into Thursday morning. Winds will subside below headline criteria
from Thursday through Friday night. High pressure will strengthen
northeast of the area by the weekend which will bring a return of
cautionary level winds by Saturday afternoon.
&&
.FIRE WEATHER...
Showers early this morning, will exit the region to the east by
midday with drier air moving in from the west. However, even with
the drier airmass, lower temperatures will keep humidity values
above critical levels. The next chance for red flag conditions will
be late in the week as the airmass remains dry, and temperatures
begin to warm.
&&
.HYDROLOGY...
The upcoming rainfall for tonight and Tuesday is not expected to
be heavy enough to create flooding concerns, and there are no
significant river rises expected over the next week across the
area.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 70 44 67 39 68 / 10 10 0 0 0
Panama City 68 48 69 44 67 / 10 0 0 0 0
Dothan 64 43 66 39 67 / 10 0 0 0 0
Albany 63 40 65 39 67 / 10 10 0 0 0
Valdosta 67 41 64 39 66 / 20 10 0 0 0
Cross City 71 44 67 38 69 / 30 10 0 0 0
Apalachicola 69 46 68 42 66 / 10 0 0 0 0
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...Harrigan
SHORT TERM...Harrigan/Barry
LONG TERM...Camp
AVIATION...Harrigan
MARINE...Barry
FIRE WEATHER...Camp
HYDROLOGY...Barry
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
657 AM EST TUE NOV 6 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 518 AM EST TUE NOV 6 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE OVER
THE WRN CONUS AND A TROUGH OVER THE EAST RESULTING IN NW FLOW FROM
WRN CANADA THROUGH THE PLAINS. AN UPSTREAM SHORTWAVE TROUGH
EXTENDING FROM NW MN INTO NW IA WAS DIVING TO THE SOUTHEAST. AT THE
SFC...A TROUGH EXTENDED FROM LAKE WINNIPEG THROUGH WRN MN INTO ERN
NEBRASKA. A BAND OF 290K-295K ISENTROPIC LIFT AHEAD OF THE TROUGH
AND WEAK TO MODERATE 700-500 MB QVECTOR CONV SUPPORTED AN AREA OF
PCPN FROM NE MN INTO NRN IA. THE STRONGER FORCING ASSOCIATED WITH
THE SHORTWAVE REMAINED TO THE SOUTH OVER SRN MN. MOST OF THE PCPN
WAS FALLING AS RAIN WITH -SN ON THE BACK EDGE OF THE PCPN OVER NE MN.
IR LOOP SHOWED THAT MID CLOUDS HAD SPREAD ACROSS THE WEST HALF OF
UPPER MI WHILE ANOTHER BAND OF CLOUDS OFF OF LAKE MI HAD EXPANDED
OVER THE ERN CWA.
TODAY...WITH THE STRONGER DYNAMICS ASSOCIATED WITH THE SHRTWV
PASSING TO THE SW OF UPPER MI...MODELS HAVE TRENDED TOWARD SMALLER
QPF AMOUNTS THROUGH THE AREA...ESPECIALLY OVER THE EAST AND WHERE
DOWNSLOPE FLOW PREVAILS N CNTRL NEAR LAKE SUPERIOR. FCST CONTINUED
TO UTILIZE NAM WET-BULB ZERO HEIGHTS IN DEFINING WARM LAYER FOR PCPN
TYPE WITH MAINLY SNOW OVER THE HIGHER TERRAIN WEST AND RAIN
ELSEWHERE. WITH QPF LESS THAN A TENTH OF AN INCH...SNOW AMOUNTS
SHOULD ALSO AMOUNT TO LESS THAN AN INCH. WITH 850 MB TEMPS TO AROUND
-5C AND NRN LAKE MI WATER TEMP NEAR 10C...HIGHER RES MODELS SUGGEST
THAT INSTABILITY WILL BE GREAT ENOUGH TO SUPPORT A BAND OF PCPN OFF
OF LAKE MI. THE BAND WOULD BE EXPECTED TO DEVELOP ACROSS THE ERN
LAKE TO THROUGH BEAVER ISLAND INTO MACKINAC AND FAR SE LUCE COUNTY.
AS THE DEEPER MOISTURE MOVES IN DURING THE AFTERNOON AND WINDS VEER
FROM SW TO S THE BAND MAY SHIFT TO NEAR MANISTIQUE/GRAND MARAIS AND
THEN TOWARD THE GARDEN PENINSULA AND CNTRL ALGER COUNTY TONIGHT.
CONFIDENCE IN THESE DETAILS IS STILL LIMITED AND ONLY LIGHT PCPN
AMOUNTS ARE EXPECTED. LOW LEVEL TEMP PROFILES SUGGEST THAT THE PCPN
WOULD BE MAINLY RAIN.
MODELS HAVE TRENDED TOWARD A SLOWER PROGRESSION WITH THE SFC TROUGH
SOT THAT A SWITCH TO ONSHORE FLOW OVER THE WEST WILL BE DELAYED.
HOWEVER...SOME LINGERING SNOW/RAIN SHOWERS MAY BE POSSIBLE NEAR THE
TROUGH AXIS...ESPECIALLY DURING THE EVENING. 850 MB TEMPS NEAR -4C
AND ONLY WEAK ONSHORE NW FLOW LATE TONIGHT WILL ONLY PROVIDE
MARGINAL SUPPORT FOR LAKE ENHANCED PCPN. SO...ANY PCPN AMOUNTS WILL
BE VERY LIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 518 AM EST TUE NOV 6 2012
BY 12Z WEDNESDAY THE 500MB WAVES WILL BE JOINING FORCES ACROSS THE
OHIO VALLEY TO MID ATLANTIC STATES...WITH THE RIDGE OVER MUCH OF THE
W HALF OF THE NATION. EXPECT THE RIDGE TO BUILDING BACK ACROSS THE
UPPER GREAT LAKES ON WEDNESDAY...THANKS TO OUR NEXT SIGNIFICANT
SYSTEM DROPPING FROM THE GULF OF AK TO THE PACIFIC NW. MOISTURE WILL
BE ON THE DECREASE...WITH INVERSION HEIGHTS STEADILY LOWERING AOB
4-5KFT. THE 500MB RIDGE OVERHEAD WILL BECOME SUPPRESSED THURSDAY
AFTERNOON THROUGH FRIDAY...WITH ZONAL FLOW...THANKS TO A SYSTEM
SWINGING ACROSS E CANADA. EXPECT A WEAK COLD FRONT TO NEAR FROM THE
W/NW FRIDAY IN BETWEEN THE SYSTEM OVER CANADA AND THE NEXT SYSTEM OF
CONCERN ORGANIZING ACROSS THE WY/CO ROCKIES. THIS WILL DO LITTLE FOR
US...OTHER THAN BRING CLOUDS TO THE REGION AND A FEW SHOWERS.
THE COLD FRONT SHOULD PUSH NORTH IN THE FORM OF A WARM FRONT ON
SATURDAY IN ADVANCE OF THE LOW PRESSURE ACROSS THE CENTRAL PLAINS
STATES. BY 00Z SUNDAY THE WX MAP SHOULD SHOW THE ELONGATED SFC LOW
STRETCHED FROM W MN TO KS...AND THE 500MB TROUGH TAKING UP THE W
HALF OF THE NATION. ALONG WITH A WARM UP INTO THE LOW 50S ON
INCREASED SOUTHERLY WINDS FOR THE WEEKEND THIS SYSTEM WILL LIKELY
ALSO BRING WET WEATHER AND THUNDERSTORMS AS THE SFC LOW LIFTS INTO
ONTARIO ON SUNDAY. KEPT THE SLIGHT CHANCE TS POTENTIAL FOR SATURDAY
AFTERNOON THROUGH SUNDAY MORNING...DIMINISHING W TO E DURING THE
AFTERNOON. KEPT NON-DIURNAL TEMPS FOR SUNDAY...WITH LOWERING VALUES
W TO E DURING THE DAY AS COLDER AIR RUSHES IN. IF TIMING OF THE COLD
FRONT STAYS CONSISTENT...WILL LIKELY NEED TO INCREASE TEMPS A BIT
OVER THE DOWNSLOPE AREAS NEAR LAKE SUPERIOR E OF MQT /GIVEN STEADY
20KT S FLOW AT THE SFC AND 850MB WINDS OF 45-50KTS/.
TEMPS SHOULD BE COLD ENOUGH FOR SNOW OVER FAR W UPPER MI BY 00Z
MONDAY. HOWEVER...THE BULK OF THE MOISTURE WILL BE E BY THEN. THE
00Z GFS OFF OF BUFKIT WAS INDICATING THE POTENTIAL FOR 4-5IN AT
IWD...AND AROUND 2.5IN AT CMX THROUGH 12Z TUESDAY. STILL...SOME OF
THE COLDEST AIR OF THE YEAR SLIDING OVER LAKE SUPERIOR AND FAVORABLE
WINDS SHOULD BE ENOUGH TO SUSTAIN LAKE EFFECT SNOW AS THE 500MB
TROUGH SLOWLY MOVES ACROSS AND E OF THE AREA. THE 2-5IN MAY END UP
BEING A LOW ESTIMATE IF THE 06/00Z GFS IS CORRECT...WITH A SECONDARY
LOW DEVELOPING NEAR AK SUNDAY NIGHT AND PUSHING UP ALONG THE EXITING
COLD FRONT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 656 AM EST TUE NOV 6 2012
EXPECTED VFR CONDITIONS ASSOCIATED WITH WEDGE OF DRY AIR OVER
CENTRAL UPR MI/WI TO GIVE WAY TO MVFR CIGS W-E THIS MORNING
AS STRENGTHENING SRLY FLOW BTWN DEPARTING HIGH PRES IN SE ONTARIO
AND A LOW PRES TROUGH MOVING INTO MN DRAWS MOISTER AIR TO THE N. THERE
MAY BE SOME LIGHT -RASN AS WELL...BUT PASSAGE OF MORE INTENSE
DYNAMIC FORCING TO THE SOUTH WILL LIMIT INTENSITY AND ANY VSBY
RESTRICTION. AS MOISTER AIR CONTINUES TO MOVE TO THE N...EXPECT IFR
CONDITIONS TO DEVELOP AT SAW WITH FAVORABLE UPSLOPE SSE WIND. THIS
DOWNSLOPE WIND WILL REDUCE THE THREAT OF IFR CONDITIONS AT
CMX/IWD...BUT ARRIVAL OF LO PRES TROF/ WEAKER PRES GRADIENT AT IWD
LATE IN THE TAF PERIOD SHOULD ALLOW FOR CONDITIONS TO DETERIORATE TO
IFR THERE AS WELL.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 518 AM EST TUE NOV 6 2012
SOUTH WINDS OF 15 TO 25 KNOTS AHEAD OF A TROUGH WILL DIMINISH FROM
WEST TO EAST THIS AFTERNOON AND TONIGHT. WINDS WILL THEN BECOME
LIGHT AS HIGH PRES BUILDS INTO THE AREA WEDNESDAY. SW WINDS WILL
AGAIN INCREASE INTO THE 15 TO 25 KNOT RANGE THURSDAY AS ANOTHER
TROUGH APPROACHES THE REGION. GALES MAY BE POSSIBLE BY LATE SATURDAY
INTO SUNDAY NIGHT AS A LOW PRESSURE SYSTEM LIFTS NORTHEAST THROUGH
MINNESOTA INTO NORTHWEST ONTARIO. HOWEVER...THERE IS STILL
CONSIDERABLE UNCERTAINTY WITH THE TRACK AND STRENGTH OF THE THIS
SYSTEM.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
523 AM EST TUE NOV 6 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 518 AM EST TUE NOV 6 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE OVER
THE WRN CONUS AND A TROUGH OVER THE EAST RESULTING IN NW FLOW FROM
WRN CANADA THROUGH THE PLAINS. AN UPSTREAM SHORTWAVE TROUGH
EXTENDING FROM NW MN INTO NW IA WAS DIVING TO THE SOUTHEAST. AT THE
SFC...A TROUGH EXTENDED FROM LAKE WINNIPEG THROUGH WRN MN INTO ERN
NEBRASKA. A BAND OF 290K-295K ISENTROPIC LIFT AHEAD OF THE TROUGH
AND WEAK TO MODERATE 700-500 MB QVECTOR CONV SUPPORTED AN AREA OF
PCPN FROM NE MN INTO NRN IA. THE STRONGER FORCING ASSOCIATED WITH THE
SHORTWAVE REMAINED TO THE SOUTH OVER SRN MN. MOST OF THE PCPN WAS
FALLING AS RAIN WITH -SN ON THE BACK EDGE OF THE PCPN OVER NE MN.
IR LOOP SHOWED THAT MID CLOUDS HAD SPREAD ACROSS THE WEST HALF OF
UPPER MI WHILE ANOTHER BAND OF CLOUDS OFF OF LAKE MI HAD EXPANDED
OVER THE ERN CWA.
TODAY...WITH THE STRONGER DYNAMICS ASSOCIATED WITH THE SHRTWV
PASSING TO THE SW OF UPPER MI...MODELS HAVE TRENDED TOWARD SMALLER
QPF AMOUNTS THROUGH THE AREA...ESPECIALLY OVER THE EAST AND WHERE
DOWNSLOPE FLOW PREVAILS N CNTRL NEAR LAKE SUPERIOR. FCST CONTINUED
TO UTILIZE NAM WET-BULB ZERO HEIGHTS IN DEFINING WARM LAYER FOR PCPN
TYPE WITH MAINLY SNOW OVER THE HIGHER TERRAIN WEST AND RAIN
ELSEWHERE. WITH QPF LESS THAN A TENTH OF AN INCH...SNOW AMOUNTS
SHOULD ALSO AMOUNT TO LESS THAN AN INCH. WITH 850 MB TEMPS TO AROUND
-5C AND NRN LAKE MI WATER TEMP NEAR 10C...HIGHER RES MODELS SUGGEST
THAT INSTABILITY WILL BE GREAT ENOUGH TO SUPPORT A BAND OF PCPN OFF
OF LAKE MI. THE BAND WOULD BE EXPECTED TO DEVELOP ACROSS THE ERN
LAKE TO THROUGH BEAVER ISLAND INTO MACKINAC AND FAR SE LUCE COUNTY.
AS THE DEEPER MOISTURE MOVES IN DURING THE AFTERNOON AND WINDS VEER
FROM SW TO S THE BAND MAY SHIFT TO NEAR MANISTIQUE/GRAND MARAIS AND
THEN TOWARD THE GARDEN PENINSULA AND CNTRL ALGER COUNTY TONIGHT.
CONFIDENCE IN THESE DETAILS IS STILL LIMITED AND ONLY LIGHT PCPN
AMOUNTS ARE EXPECTED. LOW LEVEL TEMP PROFILES SUGGEST THAT THE PCPN
WOULD BE MAINLY RAIN.
MODELS HAVE TRENDED TOWARD A SLOWER PROGRESSION WITH THE SFC TROUGH
SOT THAT A SWITCH TO ONSHORE FLOW OVER THE WEST WILL BE DELAYED.
HOWEVER...SOME LINGERING SNOW/RAIN SHOWERS MAY BE POSSIBLE NEAR THE
TROUGH AXIS...ESPECIALLY DURING THE EVENING. 850 MB TEMPS NEAR -4C
AND ONLY WEAK ONSHORE NW FLOW LATE TONIGHT WILL ONLY PROVIDE
MARGINAL SUPPORT FOR LAKE ENHANCED PCPN. SO...ANY PCPN AMOUNTS WILL
BE VERY LIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 518 AM EST TUE NOV 6 2012
BY 12Z WEDNESDAY THE 500MB WAVES WILL BE JOINING FORCES ACROSS THE
OHIO VALLEY TO MID ATLANTIC STATES...WITH THE RIDGE OVER MUCH OF THE
W HALF OF THE NATION. EXPECT THE RIDGE TO BUILDING BACK ACROSS THE
UPPER GREAT LAKES ON WEDNESDAY...THANKS TO OUR NEXT SIGNIFICANT
SYSTEM DROPPING FROM THE GULF OF AK TO THE PACIFIC NW. MOISTURE WILL
BE ON THE DECREASE...WITH INVERSION HEIGHTS STEADILY LOWERING AOB
4-5KFT. THE 500MB RIDGE OVERHEAD WILL BECOME SUPPRESSED THURSDAY
AFTERNOON THROUGH FRIDAY...WITH ZONAL FLOW...THANKS TO A SYSTEM
SWINGING ACROSS E CANADA. EXPECT A WEAK COLD FRONT TO NEAR FROM THE
W/NW FRIDAY IN BETWEEN THE SYSTEM OVER CANADA AND THE NEXT SYSTEM OF
CONCERN ORGANIZING ACROSS THE WY/CO ROCKIES. THIS WILL DO LITTLE FOR
US...OTHER THAN BRING CLOUDS TO THE REGION AND A FEW SHOWERS.
THE COLD FRONT SHOULD PUSH NORTH IN THE FORM OF A WARM FRONT ON
SATURDAY IN ADVANCE OF THE LOW PRESSURE ACROSS THE CENTRAL PLAINS
STATES. BY 00Z SUNDAY THE WX MAP SHOULD SHOW THE ELONGATED SFC LOW
STRETCHED FROM W MN TO KS...AND THE 500MB TROUGH TAKING UP THE W
HALF OF THE NATION. ALONG WITH A WARM UP INTO THE LOW 50S ON
INCREASED SOUTHERLY WINDS FOR THE WEEKEND THIS SYSTEM WILL LIKELY
ALSO BRING WET WEATHER AND THUNDERSTORMS AS THE SFC LOW LIFTS INTO
ONTARIO ON SUNDAY. KEPT THE SLIGHT CHANCE TS POTENTIAL FOR SATURDAY
AFTERNOON THROUGH SUNDAY MORNING...DIMINISHING W TO E DURING THE
AFTERNOON. KEPT NON-DIURNAL TEMPS FOR SUNDAY...WITH LOWERING VALUES
W TO E DURING THE DAY AS COLDER AIR RUSHES IN. IF TIMING OF THE COLD
FRONT STAYS CONSISTENT...WILL LIKELY NEED TO INCREASE TEMPS A BIT
OVER THE DOWNSLOPE AREAS NEAR LAKE SUPERIOR E OF MQT /GIVEN STEADY
20KT S FLOW AT THE SFC AND 850MB WINDS OF 45-50KTS/.
TEMPS SHOULD BE COLD ENOUGH FOR SNOW OVER FAR W UPPER MI BY 00Z
MONDAY. HOWEVER...THE BULK OF THE MOISTURE WILL BE E BY THEN. THE
00Z GFS OFF OF BUFKIT WAS INDICATING THE POTENTIAL FOR 4-5IN AT
IWD...AND AROUND 2.5IN AT CMX THROUGH 12Z TUESDAY. STILL...SOME OF
THE COLDEST AIR OF THE YEAR SLIDING OVER LAKE SUPERIOR AND FAVORABLE
WINDS SHOULD BE ENOUGH TO SUSTAIN LAKE EFFECT SNOW AS THE 500MB
TROUGH SLOWLY MOVES ACROSS AND E OF THE AREA. THE 2-5IN MAY END UP
BEING A LOW ESTIMATE IF THE 06/00Z GFS IS CORRECT...WITH A SECONDARY
LOW DEVELOPING NEAR AK SUNDAY NIGHT AND PUSHING UP ALONG THE EXITING
COLD FRONT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 617 PM EST MON NOV 5 2012
WITH EXPECTED WSHFT TO THE SSW THIS EVNG BTWN DEPARTING HI PRES IN
SE ONTARIO AND APRCHG LO PRES TROF FM THE PLAINS...EXPECT AREA OF
DRY AIR/MOCLR SKIES OVER MUCH OF WI TO MOVE IN AND RESULT IN
PREDOMINANT VFR CONDITIONS MUCH OF TNGT. THE BEST CHC FOR THE MVFR
CIGS TO LINGER WL BE AT SAW...WHERE AREA OF SC NEAR THE LK MI SHORE
IN WI TO IMT MIGHT HOLD IN THRU THE NGT. MORE LO CLDS WL THEN ARRIVE
W-E LATER TNGT IN ADVANCE OF LO PRES TROF. ALTHOUGH THE CIGS WL BE
INITIALLY VFR PER UPSTREAM OBS...LOOK FOR MVFR CONDITIONS TO
PREDOMINATE LATE TNGT THRU TUE AS STRENGTHENING SLY FLOW ADVECTS
MORE LLVL MSTR INTO THE AREA. THIS STRENGTHENING FLOW MIGHT CAUSE
MARGINAL LLWS AT IWD LATE TNGT/EARLY TUE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 518 AM EST TUE NOV 6 2012
SOUTH WINDS OF 15 TO 25 KNOTS AHEAD OF A TROUGH WILL DIMINISH FROM
WEST TO EAST THIS AFTERNOON AND TONIGHT. WINDS WILL THEN BECOME
LIGHT AS HIGH PRES BUILDS INTO THE AREA WEDNESDAY. SW WINDS WILL
AGAIN INCREASE INTO THE 15 TO 25 KNOT RANGE THURSDAY AS ANOTHER
TROUGH APPROACHES THE REGION. GALES MAY BE POSSIBLE BY LATE SATURDAY
INTO SUNDAY NIGHT AS A LOW PRESSURE SYSTEM LIFTS NORTHEAST THROUGH
MINNESOTA INTO NORTHWEST ONTARIO. HOWEVER...THERE IS STILL
CONSIDERABLE UNCERTAINTY WITH THE TRACK AND STRENGTH OF THE THIS
SYSTEM.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
944 AM EST TUE NOV 6 2012
.SYNOPSIS...
HIGH PRESSURE WILL EXTEND OVER THE AREA FROM THE NORTH TODAY. STRONG
LOW PRESSURE IS FORECAST TO DEVELOP OFF THE SOUTHEAST COAST THIS
AFTERNOON AND MOVE OFF OF THE NORTH CAROLINA COAST TONIGHT. THE LOW
WILL RAPIDLY INTENSIFY AS IT MOVES NORTHEAST OF THE AREA WEDNESDAY
INTO THURSDAY. HIGH PRESSURE WILL BUILD IN FROM THE WEST FRIDAY AND
SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 935 AM TUESDAY...SURFACE LOW PRESSURE CONSOLIDATING WELL
EAST OF THE SOUTH CAROLINA COAST...AS CLOSED LOW DROPS WELL INTO
THE DEEP SOUTH HELPING TO STRENGTHEN TO LOW OFFSHORE.
PRECIPITATION SHIELD CONTINUES TO MOVE UP THE COAST WITH LIGHT
RAIN ARRIVING DURING THE AFTERNOON HOURS. THE NAM12 AND GFS SEEMS
TO HAVE A MUCH BETTER FEEL TO THE PRECIPITATION FIELD AS THE
LATEST RAP SHOWS NO PRECIPITATION ON LAND THROUGH THE NEXT 18
HOURS. HAVE MADE ONLY MINOR TWEAKS TO THE FORECAST AT THIS TIME.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
AS OF 330 AM TUESDAY...LOW PRES WILL INTENSIFY AS IT MOVES OFFSHORE
OF OUTER BANKS OVERNIGHT WITH PCPN SHIELD AFFECTING MOST OF
AREA...BUT MAINLY ALONG AND E OF HWY 17. ADJUSTED QPF TO REFLECT
AMOUNTS OF 0.50 TO 1 INCH NEAR COAST. WITH MODELS TRENDING TO
SLIGHTLY FASTER AND WEAKER SYSTEM...EXPECT WINDS TO REMAIN BELOW
ADVISORY CRITERIA AT THIS TIME. MOS GDNC BLEND IN DECENT AGREEMENT
WITH PREVIOUS FCST MIN TEMPS...UPR 30S INLAND TO UPR 40S OBX.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AS OF 330 AM TUE...HAVE USED THE ECMWF FOR THE EXTENDED FORECAST
AS IT MATCHES UP WELL WITH HPC`S SURFACE DEPICTION OVER THE NEXT
SEVERAL DAYS. STRONG COASTAL LOW WILL BE MOVING NORTHWARD DURING
THE DAY AWAY FROM THE NORTH COAST. HIGHS WON`T MAKE IT OUT OF THE
MID TO UPPER 50S WITH A BREEZY NORTH NORTHWEST WRAPAROUND FLOW
UNDER CLOUDY SKIES. LIGHT RAIN WILL SLOWLY TAPER OFF FROM THE
SOUTHWEST DURING THE DAY. HOWEVER OVER THE NORTHERN OUTER BANKS
LIKELY POPS WILL CONTINUE THROUGH THE DAY. A SLIGHT CHANCE OF RAIN
WILL LINGER IN THE EVENING OVER THE NORTHEAST COUNTIES AND ALONG
THE OUTER BANKS AND SOUNDS. ALL RAIN WILL END SHORTLY AFTER
MIDNIGHT AS THE LOW MOVES FURTHER AWAY AND DRIER AIR BEGINS TO
WORK IN. DRY AND WARMER WEATHER IN STORE FOR THIS WEEKEND WITH
RIDGING SURFACE AND ALOFT.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH 12Z WEDNESDAY/...
AS 630 AM TUESDAY...VFR CONDITIONS EXPECTED TO PREVAIL THROUGH THIS
AFTN WITH INCREASING AND THICKENING CLOUD COVER DURING THE DAY. MVFR
CIGS AND VSBYS LIKELY THIS EVENING WITH RAIN DEVELOPING. SOME IFR
CONDITIONS PSBL NEAR COAST WITH HEAVIER PCPN THREAT.
LONG TERM /WED THROUGH SAT/
AS OF 330 AM TUE...SCATTERED SHOWERS WILL SLOWLY TAPER OFF FROM
THE SOUTHWEST DURING THE DAY WEDNESDAY AS LOW PRESSURE OFF THE
NORTH COAST MOVES AWAY. NORTH NORTHWEST WINDS WILL START OUT AT
15-20 KNOTS THEN SLOWLY DIMINISH TO 10-15 IN THE AFTERNOON. DRY
CONDITIONS AND LIGHT WINDS EXPECTED BEGINNING WEDNESDAY NIGHT AND
CONTINUING INTO THE WEEKEND WITH HIGH PRESSURE AT THE SURFACE AND
ALOFT BUILDING IN FROM THE WEST.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 940 AM TUESDAY...WINDS SHOULD RAMP UP OVER THE NEXT SEVERAL
HOURS AS LOW PRESSURE OFFSHORE SLOWLY INTENSIFIES AS UPPER ENERGY
DIVES INTO THE DEEP SOUTH. WINDS ALREADY GUSTING INTO THE LOWER
20S OVER THE PAMLICO SOUND AND AT THE BUOY OFF OF OREGON INLET.
HAVE MADE SOME MINOR ADJUSTMENTS TO THE MARINE FORECAST BUT
OVERALL ADVISORIES WILL REMAIN THE SAME.
LONG TERM /WED THROUGH SAT/
AS OF 330 AM TUE...ECMWF BETTER THAN THE GFS OR NAM WHEN MATCHED
UP WITH HPC SURFACE GRAPHICS...SO HAVE USED THE ECMWF AS THE
BASIS FOR THE WIND FORECAST. GALES/SMALL CRAFT CONDITIONS WILL BE
ONGOING WEDNESDAY. WAVE HEIGHTS WILL PEAK IN THE WATERS NORTH OF
CAPE HATTERAS WEDNESDAY AND WEDNESDAY EVENING AT AROUND 9-11 FEET.
GRADUAL IMPROVEMENT SEEN GOING INTO THURSDAY AND FRIDAY WITH
CONDITIONS IMPROVING FROM SOUTH TO NORTH AS HIGH PRESSURE AT THE
SURFACE AND ALOFT BUILDS IN FROM THE WEST RESULTING IN LIGHT WINDS
AND SEAS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 1 PM EST
THURSDAY FOR AMZ135.
SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 AM EST
THURSDAY FOR AMZ130.
GALE WARNING FROM 1 AM WEDNESDAY TO 1 AM EST THURSDAY FOR
AMZ150-152-154.
SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 4 PM EST
THURSDAY FOR AMZ156-158.
&&
$$
SYNOPSIS...JBM
NEAR TERM...CTC
SHORT TERM...JBM
LONG TERM...HSA
AVIATION...JBM/HSA
MARINE...JBM/CTC/HSA
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
214 PM EST Tue Nov 6 2012
.NEAR TERM [Through Tonight]...
The 18z CONUS NAM/Regional RAP analysis continued to depict a highly
amplified pattern across the country with the western half dominated
by deep layer ridging, and a broad trough across the east. Embedded
within the eastern U.S. trough were several disturbances, most
notably the potent shortwave moving out of the Southeast into the
Mid-Atlantic. This disturbance is forecast to be responsible for the
Nor`easter which is likely to impact the Northeast beginning
tomorrow. Further upstream, two more impulses are noted, one in the
Middle Mississippi Valley, and another in the Upper Valley. These
will impact (minimally) our region both tonight and tomorrow.
Wrap around moisture from the surface feature generated by last
nights upper level disturbance, combined with drying mid-levels are
responsible for the low clouds being experienced mainly across our
SE AL and SW GA counties. In many locations under the solid cloud
deck, temperatures have failed to reach the 60s. The clouds will
continue to scatter through the afternoon and allow more-and-more
sunlight to help warm things up. Updated afternoon highs to show
near 60 degrees in these locations, up to the lower 70s across
portions of south central Georgia and north Florida.
Overnight, the focus shifts back to the upper levels as the
aforementioned energy over the Mississippi Valley dives into the
Southeast. There may be just enough moisture with this shortwave to
generate some light showers overnight, more likely across AL and GA
rather than FL. There may also be a fog/low ceiling mixture across
AL and GA, possibly spilling into inland north Florida as well.
Overnight lows are expected to fall into the lower to middle 40s
area wide.
&&
.SHORT TERM [Wednesday Through Friday]...
The 500 mb height pattern will change quickly from Wednesday to
Friday as a broad, fairly deep trough over the Southeast (on
Wednesday) gets replaced by a deep layer ridge by Friday. It appears
there will be one last potent short wave rounding the base of this
broader trough Wednesday afternoon and evening. Like its
predecessors, this upper level disturbance will be rather strong,
but all of the latest NWP guidance indicates a lack of deep layer
moisture. There is an old saying that if the dynamics are there, the
moisture will be too, meaning that vigorous systems like this can
find ways to "squeeze" seemingly small amounts of moisture out of
the atmosphere, so we added a slight PoP to our forecast for our GA
zones. Once this disturbance passes by, there will be fair weather.
Temperatures will be seasonally cool Wednesday through Friday
morning with highs in the mid to upper 60s, and lows in the lower
40s inland (away from the cities) and upper 40s at the beaches.
Highs Friday afternoon will return to the mid 70s.
&&
.LONG TERM [Friday Night through Tuesday]...
Deep layer ridging will the dominant weather feature this weekend
into early next week, with fair weather. High temperatures will be
above average (mid to upper 70s). Lows will begin the weekend a bit
below average (lower to mid 40s inland), then warm to above average
by Monday and Tuesday (mid 50s). A cold front will move east across
the region Monday night and Tuesday, bringing with it a chance of
rain.
&&
.AVIATION [Beginning 19Z Tuesday]...
Expect cloud cover to decrease for KECP and KTLH throughout the rest
of today as dry air and mixing help thin out the cloud cover moving
in from the Northwest. While sites like KABY and KDHN will continue
to see BKN to SCT conditions with lower ceilings. For overnight
expect a mix of light fog and low ceilings to effect most sites
except KECP. This is due to the incoming shortwave in northern
Georgia sending some cloud cover and moisture into our CWA. By 13Z
most sites will clear out to VFR.
&&
.MARINE...
Conditions will be slightly below "Exercise caution" tonight, then
pick up to near caution levels Wednesday or Wednesday night.
Conditions will improve quickly Thursday afternoon.
&&
.FIRE WEATHER...
Although we will be relatively dry over the next couple of days,
relative humidity values will likely be high enough to quell the
need for any advisories. However, once deep layer ridging takes hold
by Friday, there will likely be fire weather concerns that will need
to be addressed.
&&
.HYDROLOGY...
The upcoming rainfall for tonight and Tuesday is not expected to
be heavy enough to create flooding concerns, and there are no
significant river rises expected over the next week across the
area.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 43 67 41 67 40 / 10 0 0 0 0
Panama City 49 68 46 67 47 / 10 0 0 0 0
Dothan 42 65 40 67 39 / 10 10 0 0 0
Albany 43 64 40 68 38 / 20 20 10 0 0
Valdosta 44 63 41 66 39 / 10 10 10 0 0
Cross City 45 67 41 69 40 / 10 0 0 0 0
Apalachicola 47 67 45 65 48 / 10 0 0 0 0
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM/AVIATION/FIRE WX...Harrigan/Hersey
SHORT TERM/LONG TERM/MARINE/HYDROLOGY...Fournier
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1242 PM EST TUE NOV 6 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 518 AM EST TUE NOV 6 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE OVER
THE WRN CONUS AND A TROUGH OVER THE EAST RESULTING IN NW FLOW FROM
WRN CANADA THROUGH THE PLAINS. AN UPSTREAM SHORTWAVE TROUGH
EXTENDING FROM NW MN INTO NW IA WAS DIVING TO THE SOUTHEAST. AT THE
SFC...A TROUGH EXTENDED FROM LAKE WINNIPEG THROUGH WRN MN INTO ERN
NEBRASKA. A BAND OF 290K-295K ISENTROPIC LIFT AHEAD OF THE TROUGH
AND WEAK TO MODERATE 700-500 MB QVECTOR CONV SUPPORTED AN AREA OF
PCPN FROM NE MN INTO NRN IA. THE STRONGER FORCING ASSOCIATED WITH
THE SHORTWAVE REMAINED TO THE SOUTH OVER SRN MN. MOST OF THE PCPN
WAS FALLING AS RAIN WITH -SN ON THE BACK EDGE OF THE PCPN OVER NE MN.
IR LOOP SHOWED THAT MID CLOUDS HAD SPREAD ACROSS THE WEST HALF OF
UPPER MI WHILE ANOTHER BAND OF CLOUDS OFF OF LAKE MI HAD EXPANDED
OVER THE ERN CWA.
TODAY...WITH THE STRONGER DYNAMICS ASSOCIATED WITH THE SHRTWV
PASSING TO THE SW OF UPPER MI...MODELS HAVE TRENDED TOWARD SMALLER
QPF AMOUNTS THROUGH THE AREA...ESPECIALLY OVER THE EAST AND WHERE
DOWNSLOPE FLOW PREVAILS N CNTRL NEAR LAKE SUPERIOR. FCST CONTINUED
TO UTILIZE NAM WET-BULB ZERO HEIGHTS IN DEFINING WARM LAYER FOR PCPN
TYPE WITH MAINLY SNOW OVER THE HIGHER TERRAIN WEST AND RAIN
ELSEWHERE. WITH QPF LESS THAN A TENTH OF AN INCH...SNOW AMOUNTS
SHOULD ALSO AMOUNT TO LESS THAN AN INCH. WITH 850 MB TEMPS TO AROUND
-5C AND NRN LAKE MI WATER TEMP NEAR 10C...HIGHER RES MODELS SUGGEST
THAT INSTABILITY WILL BE GREAT ENOUGH TO SUPPORT A BAND OF PCPN OFF
OF LAKE MI. THE BAND WOULD BE EXPECTED TO DEVELOP ACROSS THE ERN
LAKE TO THROUGH BEAVER ISLAND INTO MACKINAC AND FAR SE LUCE COUNTY.
AS THE DEEPER MOISTURE MOVES IN DURING THE AFTERNOON AND WINDS VEER
FROM SW TO S THE BAND MAY SHIFT TO NEAR MANISTIQUE/GRAND MARAIS AND
THEN TOWARD THE GARDEN PENINSULA AND CNTRL ALGER COUNTY TONIGHT.
CONFIDENCE IN THESE DETAILS IS STILL LIMITED AND ONLY LIGHT PCPN
AMOUNTS ARE EXPECTED. LOW LEVEL TEMP PROFILES SUGGEST THAT THE PCPN
WOULD BE MAINLY RAIN.
MODELS HAVE TRENDED TOWARD A SLOWER PROGRESSION WITH THE SFC TROUGH
SOT THAT A SWITCH TO ONSHORE FLOW OVER THE WEST WILL BE DELAYED.
HOWEVER...SOME LINGERING SNOW/RAIN SHOWERS MAY BE POSSIBLE NEAR THE
TROUGH AXIS...ESPECIALLY DURING THE EVENING. 850 MB TEMPS NEAR -4C
AND ONLY WEAK ONSHORE NW FLOW LATE TONIGHT WILL ONLY PROVIDE
MARGINAL SUPPORT FOR LAKE ENHANCED PCPN. SO...ANY PCPN AMOUNTS WILL
BE VERY LIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 518 AM EST TUE NOV 6 2012
BY 12Z WEDNESDAY THE 500MB WAVES WILL BE JOINING FORCES ACROSS THE
OHIO VALLEY TO MID ATLANTIC STATES...WITH THE RIDGE OVER MUCH OF THE
W HALF OF THE NATION. EXPECT THE RIDGE TO BUILDING BACK ACROSS THE
UPPER GREAT LAKES ON WEDNESDAY...THANKS TO OUR NEXT SIGNIFICANT
SYSTEM DROPPING FROM THE GULF OF AK TO THE PACIFIC NW. MOISTURE WILL
BE ON THE DECREASE...WITH INVERSION HEIGHTS STEADILY LOWERING AOB
4-5KFT. THE 500MB RIDGE OVERHEAD WILL BECOME SUPPRESSED THURSDAY
AFTERNOON THROUGH FRIDAY...WITH ZONAL FLOW...THANKS TO A SYSTEM
SWINGING ACROSS E CANADA. EXPECT A WEAK COLD FRONT TO NEAR FROM THE
W/NW FRIDAY IN BETWEEN THE SYSTEM OVER CANADA AND THE NEXT SYSTEM OF
CONCERN ORGANIZING ACROSS THE WY/CO ROCKIES. THIS WILL DO LITTLE FOR
US...OTHER THAN BRING CLOUDS TO THE REGION AND A FEW SHOWERS.
THE COLD FRONT SHOULD PUSH NORTH IN THE FORM OF A WARM FRONT ON
SATURDAY IN ADVANCE OF THE LOW PRESSURE ACROSS THE CENTRAL PLAINS
STATES. BY 00Z SUNDAY THE WX MAP SHOULD SHOW THE ELONGATED SFC LOW
STRETCHED FROM W MN TO KS...AND THE 500MB TROUGH TAKING UP THE W
HALF OF THE NATION. ALONG WITH A WARM UP INTO THE LOW 50S ON
INCREASED SOUTHERLY WINDS FOR THE WEEKEND THIS SYSTEM WILL LIKELY
ALSO BRING WET WEATHER AND THUNDERSTORMS AS THE SFC LOW LIFTS INTO
ONTARIO ON SUNDAY. KEPT THE SLIGHT CHANCE TS POTENTIAL FOR SATURDAY
AFTERNOON THROUGH SUNDAY MORNING...DIMINISHING W TO E DURING THE
AFTERNOON. KEPT NON-DIURNAL TEMPS FOR SUNDAY...WITH LOWERING VALUES
W TO E DURING THE DAY AS COLDER AIR RUSHES IN. IF TIMING OF THE COLD
FRONT STAYS CONSISTENT...WILL LIKELY NEED TO INCREASE TEMPS A BIT
OVER THE DOWNSLOPE AREAS NEAR LAKE SUPERIOR E OF MQT /GIVEN STEADY
20KT S FLOW AT THE SFC AND 850MB WINDS OF 45-50KTS/.
TEMPS SHOULD BE COLD ENOUGH FOR SNOW OVER FAR W UPPER MI BY 00Z
MONDAY. HOWEVER...THE BULK OF THE MOISTURE WILL BE E BY THEN. THE
00Z GFS OFF OF BUFKIT WAS INDICATING THE POTENTIAL FOR 4-5IN AT
IWD...AND AROUND 2.5IN AT CMX THROUGH 12Z TUESDAY. STILL...SOME OF
THE COLDEST AIR OF THE YEAR SLIDING OVER LAKE SUPERIOR AND FAVORABLE
WINDS SHOULD BE ENOUGH TO SUSTAIN LAKE EFFECT SNOW AS THE 500MB
TROUGH SLOWLY MOVES ACROSS AND E OF THE AREA. THE 2-5IN MAY END UP
BEING A LOW ESTIMATE IF THE 06/00Z GFS IS CORRECT...WITH A SECONDARY
LOW DEVELOPING NEAR AK SUNDAY NIGHT AND PUSHING UP ALONG THE EXITING
COLD FRONT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1241 PM EST TUE NOV 6 2012
LIGHT RAIN AND SNOW SHOWERS WILL CONTINUE TO MOVE INTO EACH OF THE
TAF SITES THROUGH THE AFTERNOON AND EVENING HOURS. PRECIPITATION
INTENSITY SHOULD REMAIN FAIRLY LIGHT AS THE BEST FORCING IS EXPECTED
TO REMAIN SOUTH OF THE AREA...OVER CENTRAL WI. WINDS SHOULD NOT BE
TOO STRONG AT ANY OF THE TAF SITES...HOWEVER THERE COULD BE GUSTS UP
TO 20 KNOTS THROUGH THE AFTERNOON NEAR CMX AND SAW. CEILINGS WILL
LIKELY COME DOWN AT EACH OF THE TAF SITES...WITH EACH SITE DROPPING
TO IFR AND POSSIBLY LIFR AFTER MIDNIGHT TONIGHT. AS A TROUGH MOVES
ACROSS THE REGION OVERNIGHT AND REMAINS IN PLACE THROUGH EARLY
WEDNESDAY MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 518 AM EST TUE NOV 6 2012
SOUTH WINDS OF 15 TO 25 KNOTS AHEAD OF A TROUGH WILL DIMINISH FROM
WEST TO EAST THIS AFTERNOON AND TONIGHT. WINDS WILL THEN BECOME
LIGHT AS HIGH PRES BUILDS INTO THE AREA WEDNESDAY. SW WINDS WILL
AGAIN INCREASE INTO THE 15 TO 25 KNOT RANGE THURSDAY AS ANOTHER
TROUGH APPROACHES THE REGION. GALES MAY BE POSSIBLE BY LATE SATURDAY
INTO SUNDAY NIGHT AS A LOW PRESSURE SYSTEM LIFTS NORTHEAST THROUGH
MINNESOTA INTO NORTHWEST ONTARIO. HOWEVER...THERE IS STILL
CONSIDERABLE UNCERTAINTY WITH THE TRACK AND STRENGTH OF THE THIS
SYSTEM.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...KEC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
238 PM CST TUE NOV 6 2012
.SHORT TERM...TONIGHT THROUGH FRIDAY
238 PM CST TUE NOV 6 2012
THE MAIN FOCUS THROUGH FRIDAY IS WITH HOW LONG THE PRECIPITATION AND
CLOUD COVER HOLDS ON FOR INTO WEDNESDAY ALONG WHERE A COLD FRONT
WILL END UP THURSDAY INTO FRIDAY.
CURRENTLY...A BAND OF RAIN AND SNOW WILL CONTINUE TO TRACK TO THE
EAST TONIGHT AHEAD OF WHAT APPEARS TO BE A WARM FRONT RATHER THAN
A COLD FRONT EXTENDING SOUTH ALONG THE MISSISSIPPI RIVER. A
SURFACE LOW NEAR DULUTH WILL QUICKLY DROP TO THE SOUTHEAST WITH A
RIDGE OF HIGH PRESSURE MOVING INTO THE CENTRAL PLAINS. IN THE
UPPER LEVELS...AN AMPLIFIED PATTERN IS TAKING SHAPE WITH BROAD
TROUGHING ALONG THE ATLANTIC COAST AND RIDGING ACROSS THE ROCKIES.
THIS LEAVES THE UPPER MISSISSIPPI RIVER VALLEY IN NORTHWESTERLY
FLOW ALOFT WITH COOL AIR COMING INTO THE REGION FROM CANADA.
AS THE LOW DROPS DOWN TONIGHT IT WILL KEEP SOME HIGH AMOUNTS OF
MOISTURE LOCKED IN THE LOW LEVELS WITH STEEP SURFACE TO 800MB
LAPSE RATES BASED ON 06.12Z NAM/GFS AND 06.18Z RAP SOUNDINGS. WITH
ENOUGH LOW LEVEL LIFT PERSISTING THROUGH THE NIGHT AND THE DEEP
LOW LEVEL MOISTURE EXTENDING FROM NEAR THE SURFACE UP INTO THE
-10C RANGE AROUND 10KFT...SOME RAIN AND SNOW SHOWERS WILL DEVELOP/MOVE
IN WITH THE LOW THIS EVENING. THE DEPTH OF THE MOISTURE AND LIFT
SLOWLY DECREASE OVERNIGHT AS THE SYSTEM MOVES INTO THE OHIO RIVER
VALLEY WHICH MEANS THAT ICE WILL STOP BEING GENERATED AND THE
THERMAL PROFILE BECOMES MORE FAVORABLE FOR DRIZZLE. ANY LOW LEVEL
OMEGA APPEARS TO BE OUT OF THE REGION BY AROUND 12Z TOMORROW
MORNING...SO THE DRIZZLE SHOULD END BY THEN.
CONFIDENCE IS NOT HIGH WITH HOW LONG THE CLOUD COVER WILL HOLD ON
FOR...BUT HAVE GONE THE PESSIMISTIC ROUTE UNTIL THE RIDGE GETS IN
TOMORROW AFTERNOON. 06.12Z NAM/GFS SOUNDINGS DO INDICATE SOME
MOISTURE REMAINING TRAPPED UNDER A SINKING INVERSION THAT DROPS TO
AROUND 4KFT BY TOMORROW AFTERNOON. DUE TO THIS CLOUD COVER...HAVE
KEPT OVERNIGHT LOWS UP A BIT ABOVE GUIDANCE AND THEN LOWERED THEM
A FEW DEGREES TOMORROW.
THE FOCUS THEN SHIFTS TO A COLD FRONT THAT WILL DROP DOWN INTO THE
REGION AS A MID LEVEL SHORT WAVE TROUGH SKIRTS THE NORTHERN
PERIPHERY OF THE RIDGE. THE CONSENSUS BETWEEN THE 06.12Z GUIDANCE
IS TO BRING THE FRONT ACROSS CENTRAL WISCONSIN AND IOWA TO A
SURFACE LOW IN EASTERN COLORADO BY FRIDAY MORNING. IT WILL THEN
STALL AND TRANSITION TO BEING A WARM FRONT WITH LOW LEVEL WARM AIR
ADVECTION KICKING IN AS THE LOW EJECTS INTO THE PLAINS. WENT DRY
ON FRIDAY BUT WILL HAVE TO MONITOR AS THE 06.12Z GFS SHOWS ENOUGH
DEPTH TO THE MOISTURE ALONG THE FRONT THAT A FEW SHOWERS OR
DRIZZLE COULD DEVELOP.
.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY
238 PM CST TUE NOV 6 2012
THE MAIN FOCUS FOR NEXT WEEKEND IS WITH THE BROAD TROUGHING ALOFT
THAT BRINGS A DEEPENING SURFACE LOW ACROSS MINNESOTA ON SATURDAY.
PRECIPITATION SHOULD BECOME MORE WIDESPREAD FRIDAY NIGHT AS THE
WARM AIR ADVECTION STRENGTHENS AHEAD OF THE LOW. SHOWERS AND
THUNDERSTORMS WILL DEVELOP AHEAD OF A COLD FRONT IN MINNESOTA ON
SATURDAY WHERE 0-3KM MUCAPE INCREASES TO AROUND 1000 J/KG IN THE
AFTERNOON. IT APPEARS THAT THE BETTER CHANCES FOR ANY SEVERE
WEATHER WILL BE TO THE WEST NEAR THE TRACK OF THE SURFACE LOW AND
AHEAD OF THE COLD FRONT. SOME INSTABILITY HOLDS ON INTO THE
EVENING AND OVERNIGHT...BUT IS RATHER SKINNY AND WEAKENS AS THE
NIGHT PROGRESSES.
AFTER THE FRONT PASSES THROUGH EARLY ON SUNDAY...THE NEXT QUESTION
IS WITH WHETHER OR NOT THE COLD AIR WILL GET IN FAST ENOUGH WITH
THE PRECIPITATION STILL FALLING THAT IT WOULD CHANGE OVER FROM
RAIN TO SNOW. THE 06.12Z GFS IS A BIT FASTER WITH ENDING THE
PRECIPITATION ON SUNDAY WHILE THE 06.12Z ECMWF HOLDS ONTO IT A BIT
LONGER WITH A LOW TO MID LEVEL BAND OF FRONTOGENESIS WHICH COULD
END UP BEING MORE CONDUCIVE TO THE SNOW OCCURRING. TEMPERATURES
WILL PLUMMET SUNDAY THROUGH TUESDAY AS 850MB TEMPERATURES DROP TO
AROUND -12C WHICH WILL HELP TO KEEP TEMPERATURES IN THE 30S FOR
HIGHS AND 20S FOR LOWS.
&&
.AVIATION...THROUGH 18Z WEDNESDAY
1146 AM CST TUE NOV 6 2012
WATER VAPOR IMAGERY SHOW A VIGOROUS SHORT WAVE TROUGH MOVING SOUTHEAST
THROUGH EASTERN MINNESOTA. THE 06.12Z MODELS ARE IN VERY GOOD
AGREEMENT THAT THIS SYSTEM WILL MOVE SOUTHEAST ALONG THE
MISSISSIPPI RIVER THIS AFTERNOON. THIS SYSTEM WILL CONTINUE TO
PRODUCE SCATTERED RAIN SHOWERS ACROSS THE AREA THROUGH THIS
AFTERNOON. THE RAIN MAY MIX WITH SNOW AT TIMES ACROSS WISCONSIN.
IN THE WAKE OF THIS SYSTEM...DRIZZLE WILL CONTINUE INTO TONIGHT.
THINKING THAT ANY REDUCTIONS TO VISIBILITIES WILL MAINLY ALONG AND
EAST OF INTERSTATE 94 THIS AFTERNOON. CEILINGS WILL BE MAINLY MVFR FROM
THIS AFTERNOON THROUGH WEDNESDAY MORNING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
238 PM CST TUE NOV 6 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1147 AM CST TUE NOV 6 2012
.SHORT TERM...TODAY
1047 AM CST TUE NOV 6 2012
THE MESO MODELS HAVE COME IN COOLER THIS MORNING...SO LOWERED
TEMPERATURES BY ABOUT 5 DEGREES ACROSS THE AREA. RAP SOUNDINGS
SUGGEST THAT SOME LIGHT SNOW WILL BE POSSIBLE ACROSS WESTERN
WISCONSIN THIS AFTERNOON. WITH SNOW RATES LESS THAN THEY WERE THIS
MORNING...EXPECTING ADDITION SNOW AMOUNTS OF LESS THAN A HALF INCH.
FURTHER WEST...WRAP AROUND PRECIPITATION WILL MOVE INTO SOUTHEAST
MINNESOTA AND NORTHEAST IOWA THIS AFTERNOON. SINCE THERE IS GOOD
CONSENSUS OF THIS OCCURRING IN THE MODELS...ADDED SOME
PRECIPITATION CHANCES TO THESE AREAS.
.LONG TERM...FRIDAY THROUGH MONDAY
328 AM CST TUE NOV 6 2012
06.00Z MEDIUM RANGE MODEL RUNS CONTINUE TO INDICATE A LONGWAVE
TROUGH WILL MOVE INTO THE MIDDLE OF THE COUNTRY FOR THE DAY 4-7
PERIOD...BRINGING AN ACTIVE PERIOD OF WEATHER TO THE UPPER MIDWEST
FOR THE WEEKEND INTO EARLY NEXT WEEK. HOWEVER...PLENTY OF DETAIL
DIFFERENCES WITH THE TIMING/EVOLUTION OF VARIOUS SHORTWAVES TO
ROTATE THROUGH THE TROUGH AND PASS OVER OR BY THE REGION SAT INTO
MON. AGAIN...THESE DIFFERENCES NOT UNEXPECTED IN THE DAY 5-7 TIME-
FRAME BUT THEY DO LOWER FCST CONFIDENCE INTO THE AVERAGE RANGE FOR
THE LONG TERM.
AS PREVIOUS FORECASTER STATED...THE QUESTION TO START THE EXTENDED
PERIOD IS WITH HOW FAR SOUTH A COLD FRONT MAKES IT ON FRI BEFORE IT
STALLS AND TRANSITIONS TO A WARM FRONT. LATEST MODELS TEND TO WASH
OUT THIS BOUNDARY BY FRIDAY WITH A VERY BROAD TROUGH FROM THE
EASTERN CO LOW INTO EASTERN WI ON FRI. GFS THE ONLY MODEL TO PRODUCE
SOME LIGHT -RA OVER THE AREA FRI...AND IT TENDS TO BE TOO ROBUST
WITH THIS IN CAPPED WARM SECTORS. GIVEN A DIFFUSE BOUNDARY AT BEST
LEFT FRI DRY.
FIRST SHORTWAVE OUT OF THE TROUGH DEVELOPS A RATHER STRONG LOW INTO
MN BY LATE SAT...WITH THE AREA UNDER STRONG 925-850MB WARMING AHEAD
OF IT. SAT STILL LOOKS TO BE A VERY WARM DAY FOR MID NOV HOWEVER
THE LOW LEVEL JET AND GULF MOISTURE CONTINUE TO STREAM INTO THE
AREA...UNDER AN INVERSION. EVEN IN THE WARM SECTOR...SAT LOOKING TO
BE A MOSTLY CLOUDY DAY AS A 50-55 DEW POINT AIRMASS IS PUSHED
NORTHWARD OVER LOW-MID 40S SOIL/WATER TEMPS. GFS/ECMWF CONTINUE TO
INDICATE UP TO 250 J/KG OF MU CAPE OVER THE AREA SAT. WITH SOME
LIFTING IN THE 850MB LAYER UNDER FALLING HGTS ALOFT...SMALL -SHRA/
TSRA CHANCE ON SAT STILL LOOKS REASONABLE. THE STRONG COLD FRONT
STILL SLATED TO PUSH ACROSS THE AREA SAT NIGHT...INTO THE 250 J/KG
CAPE AIRMASS. STRONG FORCING SIGNAL WITH AND BEHIND THE FRONT FOR
SAT NIGHT INTO SUN. 40-70 PERCENT SHRA CHANCE THESE PERIODS LOOK
GOOD. SMALL TSRA CHANCE CONTINUES AS WELL SAT NIGHT.
SOLUTIONS LESS CLEAR-CUT FOR SUN NIGHT/MON AS THE MAIN TROUGH
BEGINS TO LIFT OUT. LATEST RUNS MORE PROGRESSIVE WITH THIS PART OF
THE TROUGH/SHORTWAVE ENERGY...TAKING THE BULK OF IT SOUTH/EAST OF
THE FCST AREA. WITH AVERAGE CONFIDENCE AT BEST BY MON...DID NOT
STRAY FROM THE MODEL/ENSEMBLE CONSENSUS ON DAY 7 FOR NOW.
&&
.AVIATION...THROUGH 18Z WEDNESDAY
1146 AM CST TUE NOV 6 2012
WATER VAPOR IMAGERY SHOW A VIGOROUS SHORT WAVE TROUGH MOVING SOUTHEAST
THROUGH EASTERN MINNESOTA. THE 06.12Z MODELS ARE IN VERY GOOD
AGREEMENT THAT THIS SYSTEM WILL MOVE SOUTHEAST ALONG THE
MISSISSIPPI RIVER THIS AFTERNOON. THIS SYSTEM WILL CONTINUE TO
PRODUCE SCATTERED RAIN SHOWERS ACROSS THE AREA THROUGH THIS
AFTERNOON. THE RAIN MAY MIX WITH SNOW AT TIMES ACROSS WISCONSIN.
IN THE WAKE OF THIS SYSTEM...DRIZZLE WILL CONTINUE INTO TONIGHT.
THINKING THAT ANY REDUCTIONS TO VISIBILITIES WILL MAINLY ALONG AND
EAST OF INTERSTATE 94 THIS AFTERNOON. CEILINGS WILL BE MAINLY MVFR FROM
THIS AFTERNOON THROUGH WEDNESDAY MORNING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
328 AM CST TUE NOV 6 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM....RRS
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1049 AM CST TUE NOV 6 2012
.SHORT TERM...TODAY
1047 AM CST TUE NOV 6 2012
THE MESO MODELS HAVE COME IN COOLER THIS MORNING...SO LOWERED
TEMPERATURES BY ABOUT 5 DEGREES ACROSS THE AREA. RAP SOUNDINGS
SUGGEST THAT SOME LIGHT SNOW WILL BE POSSIBLE ACROSS WESTERN
WISCONSIN THIS AFTERNOON. WITH SNOW RATES LESS THAN THEY WERE THIS
MORNING...EXPECTING ADDITION SNOW AMOUNTS OF LESS THAN A HALF INCH.
FURTHER WEST...WRAP AROUND PRECIPITATION WILL MOVE INTO SOUTHEAST
MINNESOTA AND NORTHEAST IOWA THIS AFTERNOON. SINCE THERE IS GOOD
CONSENSUS OF THIS OCCURRING IN THE MODELS...ADDED SOME
PRECIPITATION CHANCES TO THESE AREAS.
.LONG TERM...FRIDAY THROUGH MONDAY
328 AM CST TUE NOV 6 2012
06.00Z MEDIUM RANGE MODEL RUNS CONTINUE TO INDICATE A LONGWAVE
TROUGH WILL MOVE INTO THE MIDDLE OF THE COUNTRY FOR THE DAY 4-7
PERIOD...BRINGING AN ACTIVE PERIOD OF WEATHER TO THE UPPER MIDWEST
FOR THE WEEKEND INTO EARLY NEXT WEEK. HOWEVER...PLENTY OF DETAIL
DIFFERENCES WITH THE TIMING/EVOLUTION OF VARIOUS SHORTWAVES TO
ROTATE THROUGH THE TROUGH AND PASS OVER OR BY THE REGION SAT INTO
MON. AGAIN...THESE DIFFERENCES NOT UNEXPECTED IN THE DAY 5-7 TIME-
FRAME BUT THEY DO LOWER FCST CONFIDENCE INTO THE AVERAGE RANGE FOR
THE LONG TERM.
AS PREVIOUS FORECASTER STATED...THE QUESTION TO START THE EXTENDED
PERIOD IS WITH HOW FAR SOUTH A COLD FRONT MAKES IT ON FRI BEFORE IT
STALLS AND TRANSITIONS TO A WARM FRONT. LATEST MODELS TEND TO WASH
OUT THIS BOUNDARY BY FRIDAY WITH A VERY BROAD TROUGH FROM THE
EASTERN CO LOW INTO EASTERN WI ON FRI. GFS THE ONLY MODEL TO PRODUCE
SOME LIGHT -RA OVER THE AREA FRI...AND IT TENDS TO BE TOO ROBUST
WITH THIS IN CAPPED WARM SECTORS. GIVEN A DIFFUSE BOUNDARY AT BEST
LEFT FRI DRY.
FIRST SHORTWAVE OUT OF THE TROUGH DEVELOPS A RATHER STRONG LOW INTO
MN BY LATE SAT...WITH THE AREA UNDER STRONG 925-850MB WARMING AHEAD
OF IT. SAT STILL LOOKS TO BE A VERY WARM DAY FOR MID NOV HOWEVER
THE LOW LEVEL JET AND GULF MOISTURE CONTINUE TO STREAM INTO THE
AREA...UNDER AN INVERSION. EVEN IN THE WARM SECTOR...SAT LOOKING TO
BE A MOSTLY CLOUDY DAY AS A 50-55 DEW POINT AIRMASS IS PUSHED
NORTHWARD OVER LOW-MID 40S SOIL/WATER TEMPS. GFS/ECMWF CONTINUE TO
INDICATE UP TO 250 J/KG OF MU CAPE OVER THE AREA SAT. WITH SOME
LIFTING IN THE 850MB LAYER UNDER FALLING HGTS ALOFT...SMALL -SHRA/
TSRA CHANCE ON SAT STILL LOOKS REASONABLE. THE STRONG COLD FRONT
STILL SLATED TO PUSH ACROSS THE AREA SAT NIGHT...INTO THE 250 J/KG
CAPE AIRMASS. STRONG FORCING SIGNAL WITH AND BEHIND THE FRONT FOR
SAT NIGHT INTO SUN. 40-70 PERCENT SHRA CHANCE THESE PERIODS LOOK
GOOD. SMALL TSRA CHANCE CONTINUES AS WELL SAT NIGHT.
SOLUTIONS LESS CLEAR-CUT FOR SUN NIGHT/MON AS THE MAIN TROUGH
BEGINS TO LIFT OUT. LATEST RUNS MORE PROGRESSIVE WITH THIS PART OF
THE TROUGH/SHORTWAVE ENERGY...TAKING THE BULK OF IT SOUTH/EAST OF
THE FCST AREA. WITH AVERAGE CONFIDENCE AT BEST BY MON...DID NOT
STRAY FROM THE MODEL/ENSEMBLE CONSENSUS ON DAY 7 FOR NOW.
&&
.AVIATION...TODAY AND TONIGHT
527 AM CST TUE NOV 6 2012
AREA OF MAINLY LIGHT RAIN CONTINUES TO MAKE STEADY EASTWARD
PROGRESS WITH THE REGIONAL COMPOSITE RADAR ALREADY SHOWING THE
BACK EDGE APPROACHING THE I35 CORRIDOR. CEILINGS IN THE
PRECIPITATION WILL BE PROBLEMATIC WITH KLSE DOWN IN THE VALLEY
EXPECTED TO REMAIN MVFR WHILE KRST ON THE HIGHER TERRAIN TO BE
IFR. THE VISIBILITY IN THE PRECIPITATION WILL BE MVFR. THE
PRECIPITATION LOOKS LIKE IT SHOULD END IN KRST BY MID MORNING AND
AROUND 18Z FOR KLSE. ONCE THE PRECIPITATION ENDS...LOOK FOR THE
VISIBILITY TO COME UP TO VFR WITH MVFR CEILINGS. THE COLD FRONT
WITH THE PRECIPITATION IS BACK ACROSS WESTERN MINNESOTA INTO
NORTHWEST IOWA AND THIS SHOULD COME THROUGH BY EARLY AFTERNOON IN
KRST AND MID AFTER AT KLSE SWINGING THE WINDS AROUND TO THE
WEST/NORTHWEST. THE MIXING BEHIND THE FRONT LOOKS TO BE DEEP
ENOUGH TO PRODUCE SOME WIND GUSTS TO AROUND 20 KNOTS AT KRST. THE
CLOUDS ARE EXPECTED TO REMAIN OVER BOTH TAF SITES THROUGH THE
NIGHT WITH MVFR CEILINGS WITH CLEARING TAKING PLACE AFTER 12Z
WEDNESDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
328 AM CST TUE NOV 6 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM....RRS
AVIATION...04