Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/17/13
AREA FORECAST DISCUSSION
NWS TUCSON AZ
915 AM MST FRI NOV 15 2013
.SYNOPSIS...A PACIFIC WEATHER SYSTEM WILL MOVE INTO THE REGION TODAY
AND SATURDAY. EXPECT STRONG GUSTY WINDS TODAY WITH AREAS OF BLOWING
DUST POSSIBLE. THE SYSTEM WILL ALSO BRING INCREASING CLOUDS WITH A
FEW SHOWERS TO THE AREA. GUSTY WINDS CONTINUING SATURDAY ALONG WITH
COOLER TEMPERATURES INTO NEXT WEEK.
&&
.DISCUSSION...GOOD TRENDS ON THE 12Z KTWC SOUNDING WITH MOISTURE
SPREADING BACK IN FROM THE SOUTH PUSHING PRECIPITABLE WATER BACK UP
TO .6 FROM YESTERDAY AFTERNOON`S DIP. VALUES NEAR .75 LATER TODAY
WITH A FEW SHOWERS AROUND. HRRR TRENDS KEEP MOST OF THE MEASURABLE
PRECIP SOUTH AND EAST OF TUCSON WITH VERY LITTLE IN WESTERN AREAS
(WITH LIGHT SHOWERS BEING MORE COMMON). WIND VALUES IN THE 25-30KT
JUST ABOVE THE DECK ABOUT 2-4K FEET AGL...SHOULD MAKE IT TO LOWER
ELEVATIONS BY NOON OR SO...BREAKING EARLIER IN HIGHER ELEVATIONS.
FOCUS FOR STRONGEST WINDS WILL SHIFT TO THE NEW MEXICO BORDER
SATURDAY...WITH COCHISE COUNTY RATHER GUSTY.
AFTER THE INITIAL MODEST ENERGY SHEARING THROUGH TONIGHT WE START TO
LOSE EVEN THAT MEAGER DYNAMICS WITH A FEW MAINLY MOUNTAIN SHOWERS
HANGING ON INTO SATURDAY. REINFORCING ENERGY SUNDAY MUCH MORE
PROGRESSIVE AND FURTHER NORTH...PUSHING QUICKLY INTO THE PLAINS AND
NOT DOING MUCH THIS FAR SOUTH.
GENERALLY DRY ZONAL FLOW THE FIRST HALF OF NEXT WEEK WITH A VERY
SLOW WARMING TREND AS WE SLOWLY PICK UP MORE INFLUENCE FROM HIGH
PRESSURE ANCHORED WEST OF BAJA.
&&
.AVIATION...HIGH/MID CLOUDS WILL REMAIN OVER THE THE AREA THROUGH
THE DAY WITH OVC CLOUDS AOA 12KFT AGL. ALSO WILL HAVE SCT-BKN
CLOUDS AT 5-8K FT AGL THRU THE DAY WITH A CHANCE OF SHOWERS FROM THE
TUCSON AREA EAST. INCREASING SURFACE WIND DURING THE LATE MORNING
HOURS WITH SLY/SWLY SURFACE WIND INCREASING TO 20-30 KTS WITH GUSTS
TO 35-40 KTS THEN TAPERING OFF AFT 16/03Z. AVIATION DISCUSSION NOT
UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...AN UPPER LEVEL SYSTEM APPROACHING FROM THE NORTHWEST
WILL INCREASE WINDS ACROSS THE AREA TODAY AND SATURDAY AS IT MOVES
ACROSS THE REGION. STRONG AND GUSTY SOUTH TO SOUTHWEST WINDS WILL
DEVELOP...WITH LOCALLY BREEZY CONDITIONS FRIDAY NIGHT IN THE
NORMALLY WINDIER LOCATIONS. WHILE THE WINDS WILL BE STRONG...RED
FLAG CONDITIONS ARE NOT EXPECTED AS MINIMUM RELATIVE HUMIDITIES ARE
FORECASTED TO REMAIN ABOVE 20 PERCENT.
THERE WILL ALSO BE A CHANCE OF SHOWERS OVER THE EASTERN TWO THIRDS
OF THE AREA THIS AFTERNOON INTO EARLY SUNDAY AS THE SYSTEM PASSES
BY. SNOW SHOWERS WILL BE POSSIBLE ABOVE 8000 FT. THIS SYSTEM WILL
ALSO COOL TEMPERATURES DOWN TO NEAR AND SLIGHTLY BELOW NORMAL LEVELS
OVER THE WEEKEND.
AFTER THIS SYSTEM PASSES...A WARMING TREND WILL OCCUR THROUGH THE
MIDDLE OF NEXT WEEK WITH TEMPERATURES RISING ABOVE NORMAL ONCE AGAIN
WITH TYPICAL WINDS FOR THIS TIME OF YEAR. IT IS EXPECTED TO REMAIN
DRY THROUGH AT LEAST THE MIDDLE OF NEXT WEEK.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...WIND ADVISORY TODAY FROM 11 AM
TO 6 PM MST AZZ501>507-510-511-513>515
BLOWING DUST ADVISORY TODAY FROM 11 AM TO 6 PM MST AZZ505.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
MEYER/CERNIGLIA
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
525 PM MST SAT NOV 16 2013
.UPDATE...
ISSUED AT 525 PM MST SAT NOV 16 2013
JET AXIS WILL TRANSLATE ACROSS NWRN COLORADO TONIGHT...EXPECT THIS
TO ENHANCE OROGRAPHIC SNOW THIS EVENING. EXPECT ONE MORE BURST OF
HEAVY SNOW RATES BEFORE THE FLOW ALOFT BECOMES ANTICYCLONIC AND
THE MOISTURE ERODES FROM THE WEST (ALREADY UNDERWAY). RAP AND HRRR
MODELS SEEM TO INDICATE THAT AREAS EAST OF CRAIG WILL GET DECENT
SNOW ACCUMULATIONS THIS EVENING. ELECTED TO HOIST WINTER WEATHER ADVISORY
FOR THE STEAMBOAT SPRINGS VICINITY. CONSIDERED CRAIG/MEEKER AND
GLENWOOD SPRINGS/EAGLE AREAS AS WELL...BUT APPEARS THAT SNOWFALL
WILL NOT REACH THE 2-4 INCH RANGE FOR THESE LOCATIONS. THE I-70
CORRIDOR IS LESS LIKELY TO EXCEED 1 INCH...BUT SPOTTY ACCUMULATIONS
ON GRASSY SURFACES MAY OCCUR. THE WIND ADVISORY DID NOT PAN OUT
IN THE MOIST POST FRONTAL ENVIRONMENT AND HAS BEEN CANCELLED 1
HOUR EARLY.
&&
.SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 248 PM MST SAT NOV 16 2013
WINTER WEATHER PRODUCTS WILL CONTINUE FOR MOST OF THE WRN CO
MOUNTAINS. ONE SHORTWAVE TROUGH OVER NORTHERN AND CENTRAL CO THIS
AFTERNOON WILL MOVE EAST AND PRODUCE SNOWFALL IN THE MOUNTAINS AND
MIX OF RAIN AND SNOW IN THE HIGHER VALLEYS THROUGH THIS EVENING. A
BRIEF LULL SHOULD OCCUR IN THE LATE EVENING...THEN ANOTHER WEAKER
SHORTWAVE WILL MOVE OVER THE NORTHERN HALF OF CO FROM JUST BEFORE
MIDNIGHT TO JUST BEFORE SUNRISE. SKIES SHOULD CLEAR FROM WEST TO
EAST SUNDAY MORNING. TEMPS...MOISTURE AND COLD ADVECTION ARE ALL
GOOD FOR DECENT SNOW ACCUMULATION. THE 700 MB TEMPS DROPPING TO -6
AND -7 DEGREE C TONIGHT WILL BRING SNOWFALL DOWN TO VALLEY BOTTOMS
LATE. STEADY WNW ALOFT WILL PROVIDE GOOD ORGPHC SUPPORT FOR
SNOWFALL ON WEST AND NORTHWEST FACING SLOPES.
SUNDAY AND SUNDAY NIGHT SHOULD SEE DRAMATICALLY CLEARING SKIES.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 248 PM MST SAT NOV 16 2013
MONDAY WILL BE CALM AND UNEVENTFUL AS LIGHT WESTERLY WINDS FROM
WEAK RIDGING TAKE OVER THE WEATHER PATTERN. TEMPERATURES WILL
ADVANCE BACK UP TO NEAR NORMAL MONDAY AND TUESDAY BEFORE A WEAK
WAVE SWINGS BY THE NORTHERN COUNTIES THURSDAY NIGHT...PRODUCING
CLOUDY CONDITIONS AND A TRACE OF PRECIPITATION AT BEST ALONG THE
CO/WY BORDER.
THE 12Z MODELS MOVE IN A WEAK UPPER LEVEL TROUGH WHICH BRINGS A
CHANCE OF PRECIPITATION TO THE HIGHER ELEVATIONS WEDNESDAY
AFTERNOON.
THE BIG STORY IN THE LONG RANGE WILL BE A SYSTEM APPROACHING LATE
WEEK...POTENTIALLY EARLY THURSDAY OR POTENTIALLY FRIDAY DEPENDING
ON WHICH WX MODEL YOU ARE ANALYZING. CONFIDENCE IS LOW AS THE
MODELS DIVERGE ON TIMING AND SPATIAL COVERAGE OF THIS LATE WEEK
FEATURE. NONETHELESS...THE LAST FEW MODEL RUNS HAVE BEEN
SIGNALING A STRONG STORM THROUGHOUT THE GREAT BASIN FOR A COUPLE
OF DAYS NOW SO CONFIDENCE IS MODERATE FOR AN INTERESTING WX SYSTEM
TO UNFOLD LATE IN THE WEEK INTO THE WEEKEND.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 248 PM MST SAT NOV 16 2013
PRECIPITATION WILL CONTINUE THIS EVENING WITH PERIODS OF LOWERED
CIGS AND LOWERED VSBYS. RAIN AND SNOW WILL REMAIN WIDESPREAD
THROUGH ABOUT 07Z IN THE MOUNTAINS...WITH SCATTERED PCPN IN THE
LOWER VALLEYS. EXPECTING FOG TO DEVELOP BETWEEN SNOW SHOWERS
KEEPING VISIBILITY DOWN INTO EARLY SUNDAY MORNING WITH GRADUAL
IMPROVEMENT THEREAFTER. EXPECT WIDESPREAD MVFR CIGS AND VSBYS WITH
THE HEAVIER SHOWERS WITH MOUNTAINS BECOMING FQTLY OBSCD THIS
EVENING AND OVERNIGHT. LOCAL IFR TO LIFR CIGS WILL BE FOUND NEAR
THE STRONGER SHOWERS. IN ADDITION...GUSTY WESTERLY WINDS WILL BE
COMMON ACROSS THE REGION...WITH SPEEDS EXCEEDING 40 KTS. EXPECT
AREAS OF MODERATE TO STRONG TURBULENCE THROUGH THIS PERIOD.
PRECIPITATION AND GUSTY WINDS WILL END THROUGHOUT THE MORNING
SUNDAY FROM SOUTHWEST TO SOUTHEAST.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL 6 AM MST SUNDAY FOR COZ003-005-009-
014-017-018.
WINTER STORM WARNING UNTIL 6 AM MST SUNDAY FOR COZ012-019.
WINTER STORM WARNING UNTIL 11 AM MST SUNDAY FOR COZ004-010-013.
UT...NONE.
&&
$$
UPDATE...PF
SHORT TERM...CC
LONG TERM...JAM
AVIATION...TGJT
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
925 AM MST FRI NOV 15 2013
.UPDATE...
&&
.SHORT TERM...ADJUSTING WINDS UP NEAR THE FOOTHILLS AND ADJUSTING
FOR LESS CLOUD COVER. BOTH BASED ON REAL DATA.
.AVIATION...WINDS AT DIA SHOULD MAINTAIN SOME DOWNSLOPING
COMPONENT THROUGH TODAY. THERE WILL BE NO CEILING ISSUES FOR THE
NEXT 24 HOURS.
&&
.PREV DISCUSSION... /ISSUED 341 AM MST FRI NOV 15 2013/
SHORT TERM...A WK UPPER LEVEL TROUGH TRACK ACROSS THE AREA LATE
THIS AFTERNOON THROUGH TONIGHT. MOISTURE WILL GRADUALLY INCREASE
IN THE MTNS LATER THIS AFTERNOON INTO THE EVENING HOURS WITH LAPSE
RATES IN THE 6-7 C/KM. AFTER MIDNIGHT MOISTURE WILL BEGIN TO
DECREASE WITH LAPSE RATES BECOMING MORE STABLE SO SNOW SHOULD
BEGIN TO DECREASE. 700 MB FLOW WILL BE SWLY WHICH WOULD FAVOR
PORTIONS OF ZNS 31 AND 33 FOR ACCUMULATING SNOW. OVERALL AMOUNTS
LOOK TO BE IN THE 2 TO 4 INCH RANGE WITH UP TO 6 INCHES POSSIBLE
IN A FEW SPOTS THROUGH 12Z SAT. WINDS WILL BE GUSTY AT TIMES
ESPECIALLY ABV 10000 FT HOWEVER SPEEDS WILL STAY BLO HIGH WIND
CRITERIA.
OVER NERN CO IT SHOULD BE DRY TODAY AND TONIGHT WITH PERIODS OF MID
AND HIGH LEVEL CLOUDS MOVING ACROSS. AFTN HIGHS SHOULD WARM INTO
THE LOWER 60S ACROSS NERN CO HOWEVER IF MID LVL CLOUDS HANG TOGETHER
CLOSER TO THE WY-CO BORDER ALL DAY READINGS MAY STAY IN THE 50S.
LONG TERM...WILL STAY THE COURSE FOR THE FORECAST PACKAGE THIS
TIME AROUND. MODELS STILL ADVERTISE A PAIR OF FAST-MOVING TROUGHS
MOVING OVER THE STATE. ON SATELLITE IMAGERY...BOTH SYSTEMS ARE
EVIDENT WITH THE SECOND SYSTEM CONTAINING A LOT OF CLOUD COVER
OVER BRITISH COLUMBIA AND ALSO OFFSHORE. MODEL QPF FIELDS FOR BOTH
SYSTEMS ARE FAIRLY LIGHT ACROSS OUR FORECAST AREA...PROBABLY OWING
TO THE RAPID SPEED WITH WHICH THE SYSTEMS CROSS OVER THE STATE.
THE SECOND SYSTEM IS GOING TO BE ACCOMPANIED BY A POTENT UPPER
LEVEL JET WHICH WILL BE LIFTING FROM SOUTH TO NORTH ACROSS THE
STATE SUNDAY MORNING. THIS FAST FLOW COULD HELP ENHANCE SNOWFALL
IN THE MOUNTAINS A LITTLE BIT...BUT MORE IMPORTANTLY WILL PRODUCE
QUITE A BIT OF WIND OVER THE MOUNTAINS AND EAST SLOPES. CROSS
SECTIOINS DO NOT SHOW A PARTICULARLY ORGANIZED MOUNTAIN WAVE
STRUCTURE...BUT THIS MAY CHANGE OVER THE NEXT COUPLE MODEL RUNS.
WILL BE ISSUING A HIGH WIND WATCH FOR SATURDAY NIGHT AND SUNDAY
MORNING TO COVER THIS WINDY PERIOD. QUASI-GEOSTROPHIC DIAGNOSTICS
SHOW AN AWFUL LOT OF SUBSIDENCE OVER THE MOUNTAINS FROM 06Z
THROUGH 18Z ON SUNDAY...WHICH WILL MAKE IT POSSIBLE FOR THE STRONG
WINDS TO MIX DOWNWARD OVER THE CONTINENTAL DIVIDE AND FRONT RANGE
FOOTHILLS.
FROM SUNDAY AFTERNOON THROUGH MID-WEEK THINGS LOOK DRY AS ZONAL
FLOW DEVELOPS AND CONTINUES ACROSS THE WESTERN HALF OF THE
COUNTRY. TEMPERATURES SHOULD BE AROUND SEASONAL NORMALS. BY
THURSDAY...THE GFS AND ECMWF ARE POINTING TO A BIT MORE
TROUGHINESS OVER THE STATE WHICH COULD BRING A RETURN OF
PRECIPITATION TO THE MOUNTAINS AND THEN THE EASTERN PLAINS.
AVIATION...VFR TODAY AND TONIGHT WITH ONLY SOME MID AND HIGH LEVEL
CLOUDS MOVING ACROSS. WINDS HAVE BEEN WSW EARLY THIS MORNING BUT
SHOULD BECOME MORE SLY BY 14Z. FOR THIS AFTN THERE ARE SOME
DIFFERENCES BETWEEN THE RAP AND THE HRRR WITH REGARDS TO WIND
DIRECTIONS. THE HRRR SHOWS WINDS BECOMING MORE WLY WHILE THE RAP HAS
A WEAK SFC LOW DEVELOPING SOUTH OF THE AIRPORT WITH WINDS BECOMING
LIGHT ENE BY 20Z WHICH LINGER THRU 00Z. AT THIS TIME WILL KEEP
PREVIOUS WND FCST IN PLACE WITH A MORE WLY DIRECTION. FOR THIS
EVENING WINDS MAY BRIEFLY BECOME NWLY FOR A FEW HOURS BEFORE
GRADUALLY SHIFTING TO DRAINAGE AFTER 03Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY MORNING
FOR COZ035>039.
&&
$$
SHORT TERM...RPK
LONG TERM....DANKERS
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
341 AM MST FRI NOV 15 2013
.SHORT TERM...A WK UPPER LEVEL TROUGH TRACK ACROSS THE AREA LATE
THIS AFTERNOON THROUGH TONIGHT. MOISTURE WILL GRADUALLY INCREASE
IN THE MTNS LATER THIS AFTERNOON INTO THE EVENING HOURS WITH LAPSE
RATES IN THE 6-7 C/KM. AFTER MIDNIGHT MOISTURE WILL BEGIN TO
DECREASE WITH LAPSE RATES BECOMING MORE STABLE SO SNOW SHOULD
BEGIN TO DECREASE. 700 MB FLOW WILL BE SWLY WHICH WOULD FAVOR
PORTIONS OF ZNS 31 AND 33 FOR ACCUMULATING SNOW. OVERALL AMOUNTS
LOOK TO BE IN THE 2 TO 4 INCH RANGE WITH UP TO 6 INCHES POSSIBLE
IN A FEW SPOTS THROUGH 12Z SAT. WINDS WILL BE GUSTY AT TIMES
ESPECIALLY ABV 10000 FT HOWEVER SPEEDS WILL STAY BLO HIGH WIND
CRITERIA.
OVER NERN CO IT SHOULD BE DRY TODAY AND TONIGHT WITH PERIODS OF MID
AND HIGH LEVEL CLOUDS MOVING ACROSS. AFTN HIGHS SHOULD WARM INTO
THE LOWER 60S ACROSS NERN CO HOWEVER IF MID LVL CLOUDS HANG TOGETHER
CLOSER TO THE WY-CO BORDER ALL DAY READINGS MAY STAY IN THE 50S.
.LONG TERM...WILL STAY THE COURSE FOR THE FORECAST PACKAGE THIS
TIME AROUND. MODELS STILL ADVERTISE A PAIR OF FAST-MOVING TROUGHS
MOVING OVER THE STATE. ON SATELLITE IMAGERY...BOTH SYSTEMS ARE
EVIDENT WITH THE SECOND SYSTEM CONTAINING A LOT OF CLOUD COVER
OVER BRITISH COLUMBIA AND ALSO OFFSHORE. MODEL QPF FIELDS FOR BOTH
SYSTEMS ARE FAIRLY LIGHT ACROSS OUR FORECAST AREA...PROBABLY OWING
TO THE RAPID SPEED WITH WHICH THE SYSTEMS CROSS OVER THE STATE.
THE SECOND SYSTEM IS GOING TO BE ACCOMPANIED BY A POTENT UPPER
LEVEL JET WHICH WILL BE LIFTING FROM SOUTH TO NORTH ACROSS THE
STATE SUNDAY MORNING. THIS FAST FLOW COULD HELP ENHANCE SNOWFALL
IN THE MOUNTAINS A LITTLE BIT...BUT MORE IMPORTANTLY WILL PRODUCE
QUITE A BIT OF WIND OVER THE MOUNTAINS AND EAST SLOPES. CROSS
SECTIOINS DO NOT SHOW A PARTICULARLY ORGANIZED MOUNTAIN WAVE
STRUCTURE...BUT THIS MAY CHANGE OVER THE NEXT COUPLE MODEL RUNS.
WILL BE ISSUING A HIGH WIND WATCH FOR SATURDAY NIGHT AND SUNDAY
MORNING TO COVER THIS WINDY PERIOD. QUASI-GEOSTROPHIC DIAGNOSTICS
SHOW AN AWFUL LOT OF SUBSIDENCE OVER THE MOUNTAINS FROM 06Z
THROUGH 18Z ON SUNDAY...WHICH WILL MAKE IT POSSIBLE FOR THE STRONG
WINDS TO MIX DOWNWARD OVER THE CONTINENTAL DIVIDE AND FRONT RANGE
FOOTHILLS.
FROM SUNDAY AFTERNOON THROUGH MID-WEEK THINGS LOOK DRY AS ZONAL
FLOW DEVELOPS AND CONTINUES ACROSS THE WESTERN HALF OF THE
COUNTRY. TEMPERATURES SHOULD BE AROUND SEASONAL NORMALS. BY
THURSDAY...THE GFS AND ECMWF ARE POINTING TO A BIT MORE
TROUGHINESS OVER THE STATE WHICH COULD BRING A RETURN OF
PRECIPITATION TO THE MOUNTAINS AND THEN THE EASTERN PLAINS.
&&
.AVIATION...VFR TODAY AND TONIGHT WITH ONLY SOME MID AND HIGH LEVEL
CLOUDS MOVING ACROSS. WINDS HAVE BEEN WSW EARLY THIS MORNING BUT
SHOULD BECOME MORE SLY BY 14Z. FOR THIS AFTN THERE ARE SOME
DIFFERENCES BETWEEN THE RAP AND THE HRRR WITH REGARDS TO WIND
DIRECTIONS. THE HRRR SHOWS WINDS BECOMING MORE WLY WHILE THE RAP HAS
A WEAK SFC LOW DEVELOPING SOUTH OF THE AIRPORT WITH WINDS BECOMING
LIGHT ENE BY 20Z WHICH LINGER THRU 00Z. AT THIS TIME WILL KEEP
PREVIOUS WND FCST IN PLACE WITH A MORE WLY DIRECTION. FOR THIS
EVENING WINDS MAY BRIEFLY BECOME NWLY FOR A FEW HOURS BEFORE
GRADUALLY SHIFTING TO DRAINAGE AFTER 03Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY MORNING
FOR COZ035>039.
&&
$$
SHORT TERM...RPK
LONG TERM....DANKERS
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
945 AM EST FRI NOV 15 2013
.UPDATE...
MEAN HIGH PRES IS CENTERED OFF THE E COAST NEAR 35N70W WITH WEAK LOW
LEVEL TROUGHING OVER THE MS VALLEY AREA. THIS LATTER FEATURE IS
ASSOCD WITH A PROGRESSIVE SHORTWAVE TROUGH OVER THE MID MS VALLEY
AND INTO THE NRN GULF OF MEXICO. FAIRLY SHARP SFC TROUGH IS LOCATED
JUST OFF THE NE FL/SE GA COAST AND AN AREA OF SCT SHOWERS IS NOTED
JUST E OF TROUGH OVER THE COASTAL WATERS AND ANGLES NW INTO SE GA
COASTAL ZONES. ISENTROPIC UPGLIDE AND UPPER FORCING FROM APPROACHING
SHORTWAVE TROUGH IS SHOWING UP AS PRODUCING GENERALLY WEAK RADAR
RETURNS OVER THE NE GULF AND NE FL. NOT MUCH AT ALL HAS FALLEN IN
OUR FORECAST AREA WITH THESE RETURNS YET...BUT ALL MODELS INDICATE
THAT EVENTUALLY THE AIRMASS WILL CONTINUE TO MOISTEN (DRY LAYER
NOTED IN JAX SOUNDING 800-600 MB OR ABOUT 6500-14000 FT) AND
GENERATE QPF OVER NE FL AND SECTIONS OF SE GA THROUGH 7 PM THIS EVE.
HAVE UPPED OUR POPS BY 10-20% OVER THE AREA FOR TODAY AND EARLY
TONIGHT BASED ON GUIDANCE AND HRRR MODEL. CAPPED POPS AT 60-70% FOR
NOW WITH HIGHEST VALUES ACROSS CENTRAL PORTIONS OF THE CWA. HAVE
ALSO TWEAKED HIGHS A BIT LOWER OVER INTERIOR NW ZONES AS THE WEDGE
AFFECT OF THE TROUGH AND HIGH PRES OVER LAND MAINTAINS A NE TO E
WIND COMPONENT AND TEMPS HAVE ALREADY SHOWN SIGNS OF LITTLE CHANGE
DUE TO CLOUDY SKIES. RAINFALL AMOUNTS WILL BE LIGHT OVERALL BUT SOME
LOCAL AMOUNTS NEAR A QUARTER OF AN INCH OR MORE ARE POSSIBLE OVER
COASTAL GEORGIA DUE TO THE SFC TROUGH AND ASSOCD STRONGER LLVL
CONVERGENCE.
&&
.AVIATION...VFR SHOULD PREVAIL OVER THE NEXT FEW HRS BUT ANTICIPATE
MVFR BY THE AFTN MAINLY JAX METRO TAFS TO SSI AREA. VICINITY SHOWERS
LOOK GOOD BUT TEMPO MVFR GROUPS MAY EVENTUALLY BE NEEDED FOR LOWER
VSBY AND CIGS. TONIGHT...SKIES CONTINUE MOSTLY CLOUDY AND MVFR MAY
BE PREVAILING BUT SOME CONFLICTING GUIDANCE...BUT CONFIDENCE HIGH
ENOUGH TO PROBABLY MAINTAIN MVFR CIGS. MAY ALSO INTRODUCE MVFR VSBY
FOR LATE TONIGHT IN THE NEXT 18Z TAF FORECAST SET.
&&
.MARINE...FORECAST ON TRACK WITH SCEC CONDS OCCURRING IN THE
OFFSHORE WATERS WITH SELY WINDS 14G19KT AT 41012 AND SEAS UP TO 6
FT. WITHIN ABOUT 10-15 MILE OF THE COAST WINDS ARE NLY DUE TO THE
TROUGH...BUT NAM INSISTS ON THE TROUGH WEAKENING. NOT TOTALLY SOLD
ON THAT SO WILL TREND NEARSHORE WINDS A BIT DIFFERENT IN RESPECT TO
THE TROUGH.
RIP CURRENTS: MODERATE RISK DUE TO E SWELLS TODAY AND LIKELY TO
PERSIST OVER THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 65 55 74 61 / 60 50 20 20
SSI 68 60 70 63 / 70 60 30 30
JAX 71 60 72 63 / 70 60 30 30
SGJ 72 65 72 66 / 60 50 40 30
GNV 72 62 74 64 / 60 60 40 30
OCF 74 65 75 67 / 60 50 40 40
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
SHASHY/MCALLISTER
AREA FORECAST DISCUSSION...UPDATED
NWS MELBOURNE FL
410 AM EST FRI NOV 15 2013
.DISCUSSION...
CURRENT...
HIGH PRESSURE RIDGE AXIS EXTENDS EASTWARD INTO THE ATLC FROM THE
CAROLINAS WITH EASTERLY FLOW CURRENTLY IN PLACE OVER ECFL. MID-UPPER
LEVEL FLOW IS BROADLY ANTICYCLONIC WITH WATER VAPOR AND RUC ANLYS
FIELDS SUGGESTING A WEAK MID (AND POSSIBLE LOW) LEVEL TROUGH LIFTING
NE FROM AROUND THE YUCATAN CHANNEL. IR SATELLITE IMAGERY SHOWS
EXPANSE OF HIGH LEVEL CLOUDS/MOISTURE OVERSPREADING THE PENINSULA.
FEW SPRINKLES COMING INTO SAINT LUCIE/INDIAN RIVER COUNTIES FROM THE
ATLC...BUT OF NIL CONSEQUENCE.
TODAY/TONIGHT...
MID AND UPPER LEVEL MOISTURE WILL CONTINUE TO SPREAD NE AND EAST
ACROSS FL TODAY/TONIGHT...RESULTING IN A "TOP-DOWN" MOISTENING OF
THE LOCAL AIR MASS...AS INDICATED BY MODEL SOUNDINGS. AFOREMENTIONED
WEAK MID LEVEL VORT TO THE SW OF FL WILL CROSS THE STATE IN THE
18Z-00Z TIME FRAME...BUT DRY AIR IN THE H85-H50 LAYER DOESN`T APPEAR
TO COMPLETELY SATURATE UNTIL ABOUT 21Z. EXPECT WE`LL SEE MID-HIGH
LEVEL CLOUDS THICKEN AND LOWER AS THE DAY PROGRESSES WITH VIRGA AND
SPRINKLES FALLING OUT OF THE MID DECK.
BETTER CHANCE FOR MEASURABLE (LIGHT) RAIN SHOULD COMMENCE BY
MID-LATE AFTERNOON THEN CONTINUE POST-SUNSET BEFORE TAPERING OFF AS
THE IMPULSE MOVES OUT OVER THE ATLC. WHILE POPS GO FROM 30-50 TODAY
TO 50-60 TONIGHT THIS ISN`T LOOKING LIKE A HUGE QPF EVENT...ALTHOUGH
ANY RAINFALL IS WELCOME GIVEN THE INCREASINGLY DRY CONDITIONS.
CLOUDS SHOULD HOLD TEMPS DOWN IN THE 70S ACROSS MOST LOCALES...
ALTHOUGH SOME READINGS AROUND 80F WILL BE POSSIBLE ACROSS THE SRN
CWA...AS COASTAL AREAS THERE REMAIN IN THE L70S ATTM.
SAT-SUN...
THE DEEP HI PRES RIDGE CENTERED OFF THE CAROLINA COAST WILL LIFT
INTO THE NW ATLC...PULLED BY A 110KT H25 JET MAX OVER ERN CANADA AND
PUSHED BY A 100KT ZONAL JET MAX OVER THE DEEP SOUTH. A PERSISTENT
E/SE SFC/LOW LVL FLOW WILL PREVAIL THRU LATE SUNS AS THE RIDGE
ELONGATES...BEFORE VEERING TO THE S/SW SUN NIGHT AHEAD OF THE NEXT
FRONTAL TROF. THIS WILL MAINTAIN A MILD WX PATTERN ACRS CENTRAL FL
THRU THE UPCOMING WEEKEND WITH TEMPS ABV AVG FOR MID NOV. MAXES IN
THE L/M80S WILL BE 5-8F ABV AVG...MINS IN THE M/U60S INTERIOR AND
U60S/L70S ALONG THE COAST WILL BE 10-15F ABV AVG.
UPSTREAM...A STRONG 160KT JET STREAK PUSHING INTO THE GULF OF AK
WILL ADD ITS ENERGY TO THE TROFFING PATTERN OVER THE WRN U.S...
ALLOWING IT TO CONSOLIDATE AND LIFT NE WHILE BECOMING NEGATIVELY
TILTED OVER THE GREAT LAKES. THE INDUCED MID LVL RIDGING OVER THE
ERN U.S. WILL FORCE AN H85-H50 ANTICYCLONE CENTERED BTWN CUBA AND
THE BAHAMA BANK TO RETROGRADE INTO THE CENTRAL GOMEX. THIS WILL
GENERATE A S/SWRLY FLOW THRU THE H85-H50 LYR THAT WILL GENERATE WEAK
ISENTROPIC LIFT.
THE LCL AIRMASS WILL BECOME FULLY MODIFIED S OF THE I-4 CORRIDOR
WITH PWAT VALUES CLIMBING INTO THE 1.8"-2.0" RANGE. HOWEVER...LITTLE
IN THE WAY OF MID/UPR LVL SUPPORT WILL BE AVAILABLE AS THE SRN
BRANCH OF THE JET BECOMES ZONAL WHILE THE MID LVL RIDGE BLOCKS OUT
ANY SIG VORT IMPULSES. WITH SUCH HI PWAT VALUES ITS HARD TO ARGUE
AGAINST NUMERICAL GUIDANCE POPS...BUT WITH SUCH WEAK FORCING IN
PLACE WILL EXPECT IT WILL BE LOW QPF STRATIFORM RAIN OR SHALLOW
CONVECTION AT BEST.
MON-THU...
LITTLE CHANGE TO THE PREV FCST REASONING AS THE 00Z GFS/ECMWF
GUIDANCE MAINTAINS A RELATIVELY LOW AMPLITUDE WX PATTERN ACRS THE
CONUS THRU MIDWEEK. A STRONG WINTER STORM WILL DVLP ACRS NEW ENGLAND
AND ERN CANADA AS THE AFOREMENTIONED TROF BECOMES NEGATIVELY TILTED.
HOWEVER...IT WILL FORM TOO FAR TO THE N TO CRANK THE COLD FRONT
CLEAN THROUGH THE FL PENINSULA...LEAVING MOST OF ITS SWD PUSH TO THE
POST FRONTAL POLAR AIRMASS. EVEN THIS WILL BE HAMPERED BY THE ZONAL
NATURE OF THE MID LATITUDE FLOW THAT WILL CARRY THE BULK OF THE
RIDGE MORE TO THE E/NE ACRS THE OH VALLEY/GREAT LAKES REGION THAN
E/SE INTO THE TN VALLEY/DEEP SOUTH REGION.
HOW FAR SOUTH THE COLD FRONT WILL PUSH WILL DEPEND ON HOW QUICKLY
THE POST FRONTAL RIDGE GETS CAUGHT IN THE ZONAL FLOW PATTERN...BUT
IS LIKELY WILL LAY DOWN IN A WSW-ENE ORIENTATION OVER THE FL
PANHANDLE BEFORE DRIFTING INTO THE CENTRAL PENINSULA THROUGH
MIDWEEK. ECMWF INDICATES THE FRONTAL TROF WILL HAVE HAVE A LITTLE
MORE AMPLITUDE THAN THE GFS SOLUTION AND THUS INDICATES THE FRONT
PUSHING INTO S FL BEFORE STALLING BY 00Z WED. NOT SURPRISINGLY...THE
ECX MOS GUIDANCE IS SIGNIFICANTLY DRIER THAN THE MEX MOS AFT 12Z TUE
THOUGH TEMP DIFFERENCES ARE LARGELY INSIGNIFICANT. WILL LEAN TOWARD
THE WETTER GFS SOLUTION THRU MIDWEEK AS A STRONG NE FLOW DVLPS WITH
THE RIDGE PUSHING INTO THE ERN CONUS...THOUGH ANY PRECIP WOULD BE IN
THE FORM OF LOW-TOPPED SHRAS WITH LIMITED QPF POTENTIAL.
&&
.AVIATION...
VFR. WIDESPREAD CIGS AOA 200 WITH LCL BKN050-060 ALONG THE COAST.
CIGS GRADUALLY LOWERING TO BKN060-100 BY LATE AFTERNOON/ EARLY
EVENING. LCL MVFR VSBYS PSBL IN LIGHT RAIN...ALTHOUGH CIGS IN PRECIP
ARE EXPECTED TO REMAIN ABOVE MVFR THRESHOLD.
&&
.MARINE...
TODAY-TONIGHT...CURRENT BUOY/C-MAN OBS COUPLED WITH 00Z MODEL
GUIDANCE SUGGEST WINDS WILL SUBSIDE EARLIER/FASTER THAN PREVIOUSLY
THOUGHT. AS SUCH...MADE SOME ADJUSTMENTS TO THE INHERITED SCA...
GOING WITH AN SCA FROM BREVARD COUNTY SOUTHWARD. THE SCA WILL EXPIRE
NEAR SHORE (0-20NM) AT 10 AM...AND WILL RUN UNTIL 4PM FROM 20-60NM.
OTHERWISE ONLY A VERY SLOW DECREASE IN SEAS IS INDICATED AS WINDS
GRADUALLY SUBSIDE INTO THE 12-17KT RANGE.
SAT-SUN...DEEP HI PRES RIDGE EXTENDING FROM JUST OFF THE CAROLINA
COAST INTO THE WRN GOMEX WILL MAINTAIN A GENTLE TO MODERATE E/SE
BREEZE ACRS THE LCL ATLC THRU THE WEEKEND. ERLY SWELL WILL GRADUALLY
DAMPEN OUT BUT WILL REMAIN HIGH ENOUGH TO KEEP SEAS IN THE 4-5FT
RANGE THRU SUNDAY EVNG...DECREASING TO 3-4FT SUN NIGHT.
MON-MON NIGHT...THE HI PRES WILL ERODE AHEAD OF THE NEXT COLD
FRONT...EXPECTED TO PUSH INTO FL THE FL PENINSULA LATE IN THE EVNG.
LIGHT TO GENTLE SRLY BREEZE WILL PREVAIL THRU MOST OF THE DAY. NORTH
OF THE CAPE...WINDS BCMG A GENTLE W/SW AFT SUNSET...THEN FRESHENING
OUT OF THE N AS THE FRONT PUSHES INTO THE CENTRAL PENINSULA. SOUTH
OF THE CAPE...WINDS BCMG LIGHT TO GENTLE S/SW AFT SUNSET...GRADUALLY
VEERING TO THE W THRU DAYBREAK. SEAS 3-4FT THRU THE DAY...BUILDING
TO 4-6FT OVER THE OFFSHORE WATERS OVERNIGHT.
TUE-TUE NIGHT...DETERIORATING CONDITIONS THRU THE DAY...BCMG
HAZARDOUS OVERNIGHT AS A STRONG BUT SHALLOW POST FRONTAL RIDGE
PUSHES THE COLD FRONT INTO S FL. MODERATE TO FRESH N/NE BREEZE EARLY
BCMG FRESH TO STRONG FROM THE NE AREAWIDE BY SUNSET WITH OCNL GUSTS
TO GALE FORCE. SEAS BUILDING TO 4-5FT NEARSHORE AND 6-8FT OFFSHORE
THRU THE DAY...THEN 6-8FT NEARSHORE AND 8-10FT OFFSHORE OVERNIGHT.
ROUGH SHORT PD WAVES EXPECTED DUE TO THE PREVAILING NRLY WIND
COMPONENT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 74 68 80 70 / 50 50 30 20
MCO 76 66 82 67 / 40 60 40 30
MLB 77 71 82 72 / 30 50 40 20
VRB 79 72 82 72 / 30 60 40 20
LEE 74 66 82 67 / 50 50 40 30
SFB 76 68 82 67 / 50 50 40 20
ORL 77 67 82 67 / 50 60 40 30
FPR 79 72 82 73 / 20 50 40 20
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR COASTAL
WATERS FROM SEBASTIAN INLET TO JUPITER INLET OUT 20 NM-
COASTAL WATERS FROM VOLUSIA BREVARD COUNTY LINE TO
SEBASTIAN INLET OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR WATERS
FROM SEBASTIAN INLET TO JUPITER INLET 20 TO 60 NM OFFSHORE-
WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET
20 TO 60 NM OFFSHORE.
SMALL CRAFT ADVISORY UNTIL 4 AM EST EARLY THIS MORNING FOR
WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE 20
TO 60 NM OFFSHORE.
&&
$$
SHORT TERM/AVIATION...CRISTALDI
LONG TERM/IMPACT WX...BRAGAW
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
335 AM EST FRI NOV 15 2013
.DISCUSSION...
CURRENT...
HIGH PRESSURE RIDGE AXIS EXTENDS EASTWARD INTO THE ATLC FROM THE
CAROLINAS WITH EASTERLY FLOW CURRENTLY IN PLACE OVER ECFL. MID-UPPER
LEVEL FLOW IS BROADLY ANTICYCLONIC WITH WATER VAPOR AND RUC ANLYS
FIELDS SUGGESTING A WEAK MID (AND POSSIBLE LOW) LEVEL TROUGH LIFTING
NE FROM AROUND THE YUCATAN CHANNEL. IR SATELLITE IMAGERY SHOWS
EXPANSE OF HIGH LEVEL CLOUDS/MOISTURE OVERSPREADING THE PENINSULA.
FEW SPRINKLES COMING INTO SAINT LUCIE/INDIAN RIVER COUNTIES FROM THE
ATLC...BUT OF NIL CONSEQUENCE.
TODAY/TONIGHT...
MID AND UPPER LEVEL MOISTURE WILL CONTINUE TO SPREAD NE AND EAST
ACROSS FL TODAY/TONIGHT...RESULTING IN A "TOP-DOWN" MOISTENING OF
THE LOCAL AIR MASS...AS INDICATED BY MODEL SOUNDINGS. AFOREMENTIONED
WEAK MID LEVEL VORT TO THE SW OF FL WILL CROSS THE STATE IN THE
18Z-00Z TIME FRAME...BUT DRY AIR IN THE H85-H50 LAYER DOESN`T APPEAR
TO COMPLETELY SATURATE UNTIL ABOUT 21Z. EXPECT WE`LL SEE MID-HIGH
LEVEL CLOUDS THICKEN AND LOWER AS THE DAY PROGRESSES WITH VIRGA AND
SPRINKLES FALLING OUT OF THE MID DECK.
BETTER CHANCE FOR MEASURABLE (LIGHT) RAIN SHOULD COMMENCE BY
MID-LATE AFTERNOON THEN CONTINUE POST-SUNSET BEFORE TAPERING OFF AS
THE IMPULSE MOVES OUT OVER THE ATLC. WHILE POPS GO FROM 30-50 TODAY
TO 50-60 TONIGHT THIS ISN`T LOOKING LIKE A HUGE QPF EVENT...ALTHOUGH
ANY RAINFALL IS WELCOME GIVEN THE INCREASINGLY DRY CONDITIONS.
CLOUDS SHOULD HOLD TEMPS DOWN IN THE 70S ACROSS MOST LOCALES...
ALTHOUGH SOME READINGS AROUND 80F WILL BE POSSIBLE ACROSS THE SRN
CWA...AS COASTAL AREAS THERE REMAIN IN THE L70S ATTM.
SAT-SUN...
THE DEEP HI PRES RIDGE CENTERED OFF THE CAROLINA COAST WILL LIFT
INTO THE NW ATLC...PULLED BY A 110KT H25 JET MAX OVER ERN CANADA AND
PUSHED BY A 100KT ZONAL JET MAX OVER THE DEEP SOUTH. A PERSISTENT
E/SE SFC/LOW LVL FLOW WILL PREVAIL THRU LATE SUNS AS THE RIDGE
ELONGATES...BEFORE VEERING TO THE S/SW SUN NIGHT AHEAD OF THE NEXT
FRONTAL TROF. THIS WILL MAINTAIN A MILD WX PATTERN ACRS CENTRAL FL
THRU THE UPCOMING WEEKEND WITH TEMPS ABV AVG FOR MID NOV. MAXES IN
THE L/M80S WILL BE 5-8F ABV AVG...MINS IN THE M/U60S INTERIOR AND
U60S/L70S ALONG THE COAST WILL BE 10-15F ABV AVG.
UPSTREAM...A STRONG 160KT JET STREAK PUSHING INTO THE GULF OF AK
WILL ADD ITS ENERGY TO THE TROFFING PATTERN OVER THE WRN U.S...
ALLOWING IT TO CONSOLIDATE AND LIFT NE WHILE BECOMING NEGATIVELY
TILTED OVER THE GREAT LAKES. THE INDUCED MID LVL RIDGING OVER THE
ERN U.S. WILL FORCE AN H85-H50 ANTICYCLONE CENTERED BTWN CUBA AND
THE BAHAMA BANK TO RETROGRADE INTO THE CENTRAL GOMEX. THIS WILL
GENERATE A S/SWRLY FLOW THRU THE H85-H50 LYR THAT WILL GENERATE WEAK
ISENTROPIC LIFT.
THE LCL AIRMASS WILL BECOME FULLY MODIFIED S OF THE I-4 CORRIDOR
WITH PWAT VALUES CLIMBING INTO THE 1.8"-2.0" RANGE. HOWEVER...LITTLE
IN THE WAY OF MID/UPR LVL SUPPORT WILL BE AVAILABLE AS THE SRN
BRANCH OF THE JET BECOMES ZONAL WHILE THE MID LVL RIDGE BLOCKS OUT
ANY SIG VORT IMPULSES. WITH SUCH HI PWAT VALUES ITS HARD TO ARGUE
AGAINST NUMERICAL GUIDANCE POPS...BUT WITH SUCH WEAK FORCING IN
PLACE WILL EXPECT IT WILL BE LOW QPF STRATIFORM RAIN OR SHALLOW
CONVECTION AT BEST.
MON-THU...
UPDATE TO FOLLOW.
&&
.AVIATION...
VFR. WIDESPREAD CIGS AOA 200 WITH LCL BKN050-060 ALONG THE COAST.
CIGS GRADUALLY LOWERING TO BKN060-100 BY LATE AFTERNOON/ EARLY
EVENING. LCL MVFR VSBYS PSBL IN LIGHT RAIN...ALTHOUGH CIGS IN PRECIP
ARE EXPECTED TO REMAIN ABOVE MVFR THRESHOLD.
&&
.MARINE...
TODAY-TONIGHT...CURRENT BUOY/C-MAN OBS COUPLED WITH 00Z MODEL
GUIDANCE SUGGEST WINDS WILL SUBSIDE EARLIER/FASTER THAN PREVIOUSLY
THOUGHT. AS SUCH...MADE SOME ADJUSTMENTS TO THE INHERITED SCA...
GOING WITH AN SCA FROM BREVARD COUNTY SOUTHWARD. THE SCA WILL EXPIRE
NEAR SHORE (0-20NM) AT 10 AM...AND WILL RUN UNTIL 4PM FROM 20-60NM.
OTHERWISE ONLY A VERY SLOW DECREASE IN SEAS IS INDICATED AS WINDS
GRADUALLY SUBSIDE INTO THE 12-17KT RANGE.
SAT-SUN...DEEP HI PRES RIDGE EXTENDING FROM JUST OFF THE CAROLINA
COAST INTO THE WRN GOMEX WILL MAINTAIN A GENTLE TO MODERATE E/SE
BREEZE ACRS THE LCL ATLC THRU THE WEEKEND. ERLY SWELL WILL GRADUALLY
DAMPEN OUT BUT WILL REMAIN HIGH ENOUGH TO KEEP SEAS IN THE 4-5FT
RANGE THRU SUNDAY EVNG...DECREASING TO 3-4FT SUN NIGHT.
MON-MON NIGHT...THE HI PRES WILL ERODE AHEAD OF THE NEXT COLD
FRONT...EXPECTED TO PUSH INTO FL THE FL PENINSULA LATE IN THE EVNG.
LIGHT TO GENTLE SRLY BREEZE WILL PREVAIL THRU MOST OF THE DAY. NORTH
OF THE CAPE...WINDS BCMG A GENTLE W/SW AFT SUNSET...THEN FRESHENING
OUT OF THE N AS THE FRONT PUSHES INTO THE CENTRAL PENINSULA. SOUTH
OF THE CAPE...WINDS BCMG LIGHT TO GENTLE S/SW AFT SUNSET...GRADUALLY
VEERING TO THE W THRU DAYBREAK. SEAS 3-4FT THRU THE DAY...BUILDING
TO 4-6FT OVER THE OFFSHORE WATERS OVERNIGHT.
TUE-TUE NIGHT...DETERIORATING CONDITIONS THRU THE DAY...BCMG
HAZARDOUS OVERNIGHT AS A STRONG BUT SHALLOW POST FRONTAL RIDGE
PUSHES THE COLD FRONT INTO S FL. MODERATE TO FRESH N/NE BREEZE EARLY
BCMG FRESH TO STRONG FROM THE NE AREAWIDE BY SUNSET WITH OCNL GUSTS
TO GALE FORCE. SEAS BUILDING TO 4-5FT NEARSHORE AND 6-8FT OFFSHORE
THRU THE DAY...THEN 6-8FT NEARSHORE AND 8-10FT OFFSHORE OVERNIGHT.
ROUGH SHORT PD WAVES EXPECTED DUE TO THE PREVAILING NRLY WIND
COMPONENT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 74 68 80 70 / 50 50 30 20
MCO 76 66 82 67 / 40 60 40 30
MLB 77 71 82 72 / 30 50 40 20
VRB 79 72 82 72 / 30 60 40 20
LEE 74 66 82 67 / 50 50 40 30
SFB 76 68 82 67 / 50 50 40 20
ORL 77 67 82 67 / 50 60 40 30
FPR 79 72 82 73 / 20 50 40 20
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR COASTAL
WATERS FROM SEBASTIAN INLET TO JUPITER INLET OUT 20 NM-
COASTAL WATERS FROM VOLUSIA BREVARD COUNTY LINE TO
SEBASTIAN INLET OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR WATERS
FROM SEBASTIAN INLET TO JUPITER INLET 20 TO 60 NM OFFSHORE-
WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET
20 TO 60 NM OFFSHORE.
SMALL CRAFT ADVISORY UNTIL 4 AM EST EARLY THIS MORNING FOR
WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE 20
TO 60 NM OFFSHORE.
&&
$$
SHORT TERM/AVIATION...CRISTALDI
LONG TERM/IMPACT WX...BRAGAW
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
403 PM CST FRI NOV 15 2013
.DISCUSSION...
1045 AM CST
UPDATE FOR REST OF TODAY...NARROW BAND OF RAIN SHOWERS WITH
SOME SLEET MIXED IN IN SPOTS CONTINUED TO WEAKEN FROM EARLY
TO MID MORNING AND HAD ALL DISSIPATED BY LATE MORNING AS THE
SE-NE ORIENTED BAND THAT OVER THE NEAR NORTH...NEAR WEST AND
FAR SOUTHWEST SUBURBS CONTINUED TO PROGRESS EASTWARD.
THIS LOW COVERAGE PRECIP WAS ASSOCIATED WITH WEAK TO MODERATE
ISENTROPIC LIFT IN THE HIGHER PORTION OF THE LOW LAYERS UP
INTO THE MID LEVELS AHEAD OF A WEAKENING MINOR DISTURBANCE
MOVING FROM EASTERN IA INTO NW AND N CENTRAL IL. DRYING/SUBSIDENCE
IN THE WAKE OF THIS MID LEVEL SHORT WAVE HAS LEAD TO A DECREASE IN
CLOUD COVER FROM NW TO N CENTRAL IL...AND INTO FAR NE IL AS THE
MORNING PROGRESSED.
TO THE SOUTH A STRONGER SHORT WAVE...OR EVEN A SMALL CLOSED UPPER
LOW PER SATELLITE LOOPS...HAD MOVED EAST-NORTHEAST FROM EASTERN
OK TO THE IA-MO BOARDER DURING THE MORNING. WHILE THE LARGE AREA
OF ISENTROPIC LIFT WAS WELL SOUTH WITH THE CORRESPONDING BROAD
AREA OF RAIN WHERE THE STRONG LIFT AHEAD OF THIS SMALL UPPER LOW
ALSO WELL SOUTH EXTENDING ACROSS MICH OF MI NORTHEASTWARD ACROSS
WESTERN TN AND TO THE MID OH VALLEY.
HOWEVER...THERE WHERE SOME SPOTTY LIGHT RAIN SHOWERS MOVING
NORTHEAST FROM CENTRAL IL TO THE FAR SOUTHWEST CORNER OF THE
LOCAL FORECAST AREA. HIGHER RESOLUTION MODEL DATA SHOWS AND AREA
OF FAIRLY WEAK LOWER UP TO NEAR THE BOTTOM OF THE MID LEVELS. LOW
STRETCHES OF THE AND MID LEVEL UPGLIDE AND SATURATION FROM W
CENTRAL IL ENE ACROSS THE SOUTHERN PORTION OF OUR CW FA AND ONTO
THE NW CORNER OF IND MIDDAY INTO EARLY EVENING AND THEN WEAKENING.
LIMITING FACTOR TO ANY THING BEYOND TRACE AMOUNTS FROM SOME
SPRINKLES OR A FEW VERY LIGHT RAIN SHOWERS.
HAVE TWEAKED SKY COVER FORECASTS TO SHOW THE TIGHT TRANSITION
FROM CLOUDY/MOSTLY CLOUDY TO CLEAR/MOSTLY CLEAR ACROSS THE
APPROXIMATELY NW QUARTER OF THE STATE. TEMPERATURE FORECASTS LOOK
TO BE ON TRACK WITHIN A DEGREE OR TWO BE SO HAVE LEFT MAX TEMPS
ALONE FOR THIS AFTERNOON.
TRS
//PREV DISCUSSION...
855 AM CST
FORECAST BRIEFLY UPDATED TO MENTION A SMALL CHANCE FOR LIGHT ICE
PELLETS/RAIN SHOWERS ACROSS FAR NORTHEAST ILLINOIS. THIS HAS BEEN
ATTRIBUTED TO SUBTLE MID-LEVEL FORCING MOVING OVERHEAD. INITIAL
REPORTS WERE OF LIGHT ICE PELLETS WITH THIS. USING THE TOP-DOWN
METHOD...IT APPEARED A LOW WET BULB BELOW CLOUD BASE SUPPORTED A
FREEZING OF THIS PRECIP. THERE MAY CONTINUE TO BE BRIEF ICE
PELLETS...BUT IT MAY BECOME MORE FAVORED TO BE LIGHT RAIN. NO
CHANGES MADE TO TEMPERATURES.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* MEDIUM CONFIDENCE IN IFR-MVFR CIGS DEVELOPING BY SATURDAY MORNING.
* MEDIUM CONFIDENCE OF GUSTY SW WINDS 15-19 KTS THIS AFTERNOON AND
GUSTY SOUTH WINDS OF 23-28 KTS DURING THE DAY SAT.
* LOW TO MEDIUM CONFIDENCE TIMING AND COVERAGE OF SHOWERS AND ISOLATED
THUNDERSTORMS AT ORD SATURDAY AFTERNOON.
ALLSOPP/MTF/07
//DISCUSSION...UPDATED 20Z...
ISOLATED LIGHT RAIN SHOWERS AND SPRINKLES OVER CENTRAL IL TO MAINLY PASS
SE OF THE NE IL AIRPORTS THIS AFTERNOON THOUGH GETTING CLOSEST TO GYY
WHERE CEILINGS COULD LOWER TO 5K FT. THESE LIGHT SHOWERS DUE TO A
SHORT WAVE TROUGH OVER MID/LOWER MS VALLEY IS PRODUCING MID LEVEL
CLOUDS ALONG AND SE OF A LINE FROM DOWNTOWN CHICAGO TO PERU AIRPORT
AND HAVE PASSED SE OF ORD AND DPA. THESE MID LEVEL CLOUDS OF 6-9K FT
TO CONTINUE TO DRIFT SE DURING MID/LATE AFTERNOON AND SCATTER OUT IN
NEXT FEW HOURS...LASTING LONGEST AT GYY WHERE CIRRUS DECKS MAY
LINGER INTO TONIGHT. MVFR CLOUDS OVER SE MO AND AR TO SPREAD NE INTO
NE IL BETWEEN 11-13Z SAT WITH SHOWERS AND ISOLATED THUNDERSTORMS
LIKELY HOLDING OFF UNTIL LATE MORNING AFTER 16Z AT RFD AND SAT
AFTERNOON OVER THE CHICAGO AREA TAF SITES. SW WINDS AROUND 10 KTS
THIS AFTERNOON WITH FEW GUSTS OF 15-19 KTS TO VEER SSE 7-9 KTS
AFTER SUNSET AND THEN BE SOUTH AND INCREASE BETWEEN 12-17 KTS AND
GUSTS INCREASING TO 23-28 KTS DURING SAT MORNING AFTER 14Z SATURDAY.
DISCUSSION...UPDATED 18Z...
LARGE HIGH PRESSURE OF 1028 MB...OFF THE NC COAST AT MIDDAY...WILL
CONTINUE TO BRING FAIR WEATHER TO THE AREA THROUGH TONIGHT. A SHORT WAVE
TROF OVER THE MID/LOWER MS VALLEY HAS MID LEVEL CLOUDS FROM CHICAGO METRO
SE AND THESE CLOUDS TO CONTINUE TO DECREASE FROM NW TO SE DURING THIS
AFTERNOON. WITH SOME SUNSHINE APPEARING/DAYTIME HEATING AND MIXING...
EXPECT A FEW GUSTS TO 15-19 KT THIS AFTERNOON. ATMOSPHERE WILL DECOUPLE
LATE AFTERNOON/EARLY EVENING AGAIN AS INVERSION REDEVELOPS WITH SW WINDS
VEERING SSE AS WINDS DROP BELOW 10 KTS TONIGHT. STRONG SURFACE LOW
PRESSURE EMERGING OVER THE NORTHERN PLAINS DURING SAT TO INCREASE PRESSURE
GRADIENT OVER NE IL ALONG WITH SOUTH WINDS INCREASING FROM 12-17 KTS AND
WIND GUSTS INCREASING FROM 22-28 KTS AFTER 14Z SAT. THINK LOW LEVEL WIND
SHEAR LATE TONIGHT AND EARLY SAT MORNING WILL BE FOCUSED SW OF NE IL AS
2-3K FT WINDS INCREASE BETWEEN 30-40 KTS. BY SATURDAY MORNING...SOUTHERLY
LOW LEVEL FLOW FROM 2-3K FT WILL INCREASE TO 30-40 KTS. THIS WILL ADVECT
GULF MOISTURE NORTHWARD. MOS GUIDANCE SUGGEST MVFR CIGS ARRIVING BY
DAYBREAK SATURDAY...AND POSSIBLY LOWERING TO IFR BY MID SAT MORNING.
SHOWERS AND ISOLATED THUNDERSTORMS SHOULD MOSTLY HOLD OFF UNTIL SAT
AFTERNOON THOUGH COULD REACH RFD AS EARLY AS 17Z AND CHICAGO TAF SITES
AFTER 18Z SAT.
OUTLOOK...SOUTH WINDS INCREASING TO 20 TO 30 MPH SATURDAY
AFTERNOON WITH SHOWERS LIKELY AND POSSIBLY A THUNDERSTORM.
ALLSOPP/07
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM CONFIDENCE IN MVFR/IFR CIGS DEVELOPING SATURDAY MORNING.
* MEDIUM TO HIGH CONFIDENCE OF WIND GUSTS AND DIRECTION THIS
AFTERNOON AND DURING THE DAY SATURDAY.
* LOW TO MEDIUM CONFIDENCE TIMING AND COVERAGE OF SHOWERS AND
ISOLATED THUNDERSTORMS AT OHARE/ORD SATURDAY AFTERNOON.
ALLSOPP/MTF
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 18Z...
SATURDAY NIGHT...SHOWERS AND SLIGHT CHANCE OF THUNDERSTORMS.
STRONG SOUTH WINDS OF 20-30 KT. MVFR LIKELY AND IFR POSSIBLE.
SUNDAY...SHOWERS AND CHANCE OF THUNDERSTORMS. STRONG SOUTH
WINDS BECOMING SOUTHWEST WITH GUSTS AT 25-35 KT AND POSSIBLY UP TO
40 KTS WITH THUNDERSTORMS. MVFR LIKELY AND IFR POSSIBLE.
MONDAY...MVFR CIG POSSIBLE. NORTHWEST WIND GUSTS OF 20 TO 25 KT.
TUESDAY-THURSDAY...VFR.
ALLSOPP/07
&&
.MARINE...
401 PM CST
PROLONGED PERIOD OF HIGH WINDS AND WAVES EXPECTED THIS WEEKEND INTO
EARLY NEXT WEEK AS LOW PRESSURE ORGANIZES OVER THE HIGH PLAINS AND
MOVES EAST... WHILE AT THE SAME TIME STRONG HIGH PRESSURE REMAINS
ANCHORED OFF THE EAST COAST. AS MULTIPLE AREAS OF LOW PRESSURE
MOVE FROM THE HIGH PLAINS TO THE MID MISSISSIPPI VALLEY AND UPPER
GREAT LAKES THEY WILL MERGE INTO A SINGLE LOW PRESSURE SYSTEM. THIS
MERGED LOW WILL THEN INTENSIFY RAPIDLY SUNDAY AND SUNDAY NIGHT AS IT
MOVES ACROSS IOWA AND WISCONSIN TO EASTERLY UPPER MICHIGAN AND THEN
TOWARDS JAMES BAY OVERNIGHT SUNDAY INTO MONDAY. WINDS WILL SURPASS
SMALL CRAFT ADVISORY THRESHOLDS SATURDAY MORNING AND QUICKLY
APPROACH GALE THRESHOLDS BY LATE MORNING ACROSS THE IL AND IN
NEARSHORE WATERS. GALE FORCE SOUTHERLY WINDS WILL OVERSPREAD THE
ENTIRE LAKE LATE MORNING SATURDAY AS WELL. A BRIEF LULL IN WINDS TO
BELOW GALE FORCE MAY TAKE PLACE BEFORE WINDS VEER TO WEST AND
NORTHWEST SUNDAY FOLLOWING PASSAGE OF A COLD FRONT. WITH THE ONSET
OF COLDER AIR SURGING INTO THE AREA... WINDS MAY INCREASE RAPIDLY
ACROSS THE LAKE TO ANOTHER HIGH END GALE EVENT AND OCCASIONAL STORM
FORCE GUSTS. LATER FORECASTS SHOULD BE MONITORED AS ATMOSPHERIC
COMPUTER MODELS BETTER RESOLVE THE LOW STRENGTH AND TRACK SUNDAY
INTO MONDAY.
ED F
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...6 AM SATURDAY TO NOON SATURDAY.
GALE WATCH...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...NOON
SATURDAY TO 6 PM SUNDAY.
GALE WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...9 AM SATURDAY TO 6 PM
MONDAY.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
245 PM CST Fri Nov 15 2013
.DISCUSSION...
ISSUED 245 PM CST Fri Nov 15 2013
Models coming into better agreement today with respect to timing
of dual system coming in this weekend.
SHORT TERM...Tonight through Sunday Night
Latest Satellite imagery confirms that partial clearing is likely
this afternoon and evening before lower clouds move in later
tonight. Will forecast a non-diurnal temperature trend with a low
during the period of clearing and then rising temperatures once
the clouds move in.
First shortwave of the weekend moves northwest of forecast area on
Saturday. Trainling cold front brings precip into western Illinois
by late morning and across most of the state by 00z. Best forcing
and shear remain across Iowa into Wisconsin. However most of the
forecast area should have at least chc pos except the extreme southeast.
The front gets hung up over Illinois Saturday Night and provides a
focus for additional shower and thunderstorm development as lapse
rates incr4ease as cold air aloft associated with the main wave
overrides the warmer southerly flow. bulk shear (0-6km) increases
overnight to over 70kts and may be further enhanced by the
boundary in place. Instability is lacking, but with that level of
shear it won`t take much for rotating cells and possible strong
wind gusts on the backside of the stronger storms.
For Sunday, 12z ECMWF and GFS now in much better agreement with
timing of second wave and associated cold front with the system
nearing the Illinois River by midday and then pushing very quickly
eastward during the afternoon. One big question is the lack of
deep moisture as indicated by time heights and forecast soundings.
This may prevent organization until the front gets into far
eastern Illinois. Again with shear values over 70 knots, it may
not take much instability to get strong winds to surface.
Whether organized line along the front or just a few broken cells,
either way the front will shoot across the state Sunday afternoon
strong subsidence will dry the atmosphere Sunday Night.
Very warm air being advected northward from the Gulf will be
tempered somewhat by clouds and precip. Models in good agreement
though with 850 mb temperatures rising into the double digits (C)
Saturday afternoon and then around 13-16C for Sunday. This
supports the current forecast of 60s Saturday and 60s and even
lower 70s Sunday. Temps drop off quickly after frontal passage
Sunday afternoon, but precip should be well east of forecast area
prior to air cold enough for a phase change.
LONG TERM...Monday through Friday
Generally zonal flow in place before next southern stream wave
approaches toward the end of the week. Temperatures should be
slightly below normal Monday and Tuesday with a gradual warming
trend Wednesday and Thursday. Models diverge significantly after
that with GFS bringing clouds and a chance of precip in Thursday
Night and Friday with ECMWF keeping moisture south of the forecast
area. Will introduce a chance of precip Thursday Night and Friday
but the forecast is highly uncertain for that time period.
Barker
&&
.AVIATION...
ISSUED 1152 AM CST Fri Nov 15 2013
VFR conditions will continue through this evening, before MVFR
ceilings arrive later tonight into Saturday morning. Southerly
winds will bring increasing amounts of moisture northward into
the area over the next 24 hours. A weak upper-level disturbance
over the lower Mississippi River Valley is currently spreading
mid-level clouds across Illinois: however, these will begin to
clear from west to east across the area late this afternoon into
the evening. 17z/11am satellite imagery shows the clouds breaking
up across north-central Missouri, with satellite timing tools
bringing this partial clearing to KPIA and KSPI by around 21/22z.
Forecast soundings indicate mostly clear conditions this evening,
before better moisture and lower clouds arrive from the south
overnight. HRRR shows low clouds spreading northward after 05z,
with extrapolation suggesting MVFR ceilings of around 1500ft
arriving at the central Illinois terminals between 07z and 09z.
Southwesterly winds of 10 to 15kt this afternoon will decrease to
around 10kt tonight. As pressure gradient tightens, southerly
winds will increase markedly on Saturday, with gusts likely
exceeding 25kt. Showers associated with an approaching short-wave
will likely remain just west of the TAF sites until Saturday
afternoon: however, have included VCSH at KPIA after 15z in case
precip arrives sooner.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
ISSUED BY NATIONAL WEATHER SERVICE LINCOLN IL
1205 PM CST FRI NOV 15 2013
.DISCUSSION...
1045 AM CST
UPDATE FOR REST OF TODAY...NARROW BAND OF RAIN SHOWERS WITH
SOME SLEET MIXED IN IN SPOTS CONTINUED TO WEAKEN FROM EARLY
TO MID MORNING AND HAD ALL DISSIPATED BY LATE MORNING AS THE
SE-NE ORIENTED BAND THAT OVER THE NEAR NORTH...NEAR WEST AND
FAR SOUTHWEST SUBURBS CONTINUED TO PROGRESS EASTWARD.
THIS LOW COVERAGE PRECIP WAS ASSOCIATED WITH WEAK TO MODERATE
ISENTROPIC LIFT IN THE HIGHER PORTION OF THE LOW LAYERS UP
INTO THE MID LEVELS AHEAD OF A WEAKENING MINOR DISTURBANCE
MOVING FROM EASTERN IA INTO NW AND N CENTRAL IL. DRYING/SUBSIDENCE
IN THE WAKE OF THIS MID LEVEL SHORT WAVE HAS LEAD TO A DECREASE IN
CLOUD COVER FROM NW TO N CENTRAL IL...AND INTO FAR NE IL AS THE
MORNING PROGRESSED.
TO THE SOUTH A STRONGER SHORT WAVE...OR EVEN A SMALL CLOSED UPPER
LOW PER SATELLITE LOOPS...HAD MOVED EAST-NORTHEAST FROM EASTERN
OK TO THE IA-MO BOARDER DURING THE MORNING. WHILE THE LARGE AREA
OF ISENTROPIC LIFT WAS WELL SOUTH WITH THE CORRESPONDING BROAD
AREA OF RAIN WHERE THE STRONG LIFT AHEAD OF THIS SMALL UPPER LOW
ALSO WELL SOUTH EXTENDING ACROSS MICH OF MI NORTHEASTWARD ACROSS
WESTERN TN AND TO THE MID OH VALLEY.
HOWEVER...THERE WHERE SOME SPOTTY LIGHT RAIN SHOWERS MOVING
NORTHEAST FROM CENTRAL IL TO THE FAR SOUTHWEST CORNER OF THE
LOCAL FORECAST AREA. HIGHER RESOLUTION MODEL DATA SHOWS AND AREA
OF FAIRLY WEAK LOWER UP TO NEAR THE BOTTOM OF THE MID LEVELS. LOW
STRETCHES OF THE AND MID LEVEL UPGLIDE AND SATURATION FROM W
CENTRAL IL ENE ACROSS THE SOUTHERN PORTION OF OUR CW FA AND ONTO
THE NW CORNER OF IND MIDDAY INTO EARLY EVENING AND THEN WEAKENING.
LIMITING FACTOR TO ANY THING BEYOND TRACE AMOUNTS FROM SOME
SPRINKLES OR A FEW VERY LIGHT RAIN SHOWERS.
HAVE TWEAKED SKY COVER FORECASTS TO SHOW THE TIGHT TRANSITION
FROM CLOUDY/MOSTLY CLOUDY TO CLEAR/MOSTLY CLEAR ACROSS THE
APPROXIMATELY NW QUARTER OF THE STATE. TEMPERATURE FORECASTS LOOK
TO BE ON TRACK WITHIN A DEGREE OR TWO BE SO HAVE LEFT MAX TEMPS
ALONE FOR THIS AFTERNOON.
TRS
&&
.PREV DISCUSSION...
855 AM CST
FORECAST BRIEFLY UPDATED TO MENTION A SMALL CHANCE FOR LIGHT ICE
PELLETS/RAIN SHOWERS ACROSS FAR NORTHEAST ILLINOIS. THIS HAS BEEN
ATTRIBUTED TO SUBTLE MID-LEVEL FORCING MOVING OVERHEAD. INITIAL
REPORTS WERE OF LIGHT ICE PELLETS WITH THIS. USING THE TOP-DOWN
METHOD...IT APPEARED A LOW WET BULB BELOW CLOUD BASE SUPPORTED A
FREEZING OF THIS PRECIP. THERE MAY CONTINUE TO BE BRIEF ICE
PELLETS...BUT IT MAY BECOME MORE FAVORED TO BE LIGHT RAIN. NO
CHANGES MADE TO TEMPERATURES.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* MEDIUM CONFIDENCE IN IFR-MVFR CIGS DEVELOPING SATURDAY MORNING.
* MEDIUM CONFIDENCE OF GUSTY SW WINDS 15-19 KTS THIS AFTERNOON AND
GUSTY SOUTH WINDS OF 22-28 KTS DURING THE DAY SAT.
* LOW TO MEDIUM CONFENCE TIMING AND COVERAGE OF SHOWERS AND ISOLATED
THUNDERSTORMS AT ORD SATURDAY AFTERNOON.
ALLSOPP/MTF/07
//DISCUSSION...UPDATED 18Z...
ISOLATED LIGHT RAIN SHOWERS AND SPRINKLES OVER CENTRAL IL TO MAINLY PASS
SOUTH OF THE NE IL AIRPORTS THIS AFTERNOON THOUGH GETTING CLOSEST TO GYY.
AS A SHORT WAVE TROUGH OVER MID/LOWER MS VALLEY IS PRODUCING MID LEVEL
CLOUDS ALONG AND SE OF A LINE FROM NORTH SIDE OF CHICAGO TO DUPAGE TO
GALESBURG SE AT MIDDAY. THESE MID LEVEL CLOUDS OF 6-9K FT TO CONTINUE TO
DRIFT SE DURING EARLY/MID AFTERNOON AND SCATTER OUT IN NEXT FEW HOURS...
LASTING LONGEST AT GYY WHERE CIRRUS DECKS MAY LINGER INTO TONIGHT.
MVFR CLOUDS OVER SOUTHERN MO TO SPREAD NE INTO NE IL BETWEEN 11-13Z SAT
WITH SHOWERS AND ISOLATED THUNDERSTORMS LIKELY HOLDING OFF UNTIL SAT
AFTERNOON...THOUGH GETTING NEAR RFD BY 17Z SAT. SW WINDS AROUND 10 KTS
THIS AFTERNOON WITH FEW GUSTS OF 15-18 KTS TO VEER SSE 7-9 KTS BY SUNSET
AND THEN BE SOUTH AND INCREASE BETWEEN 12-17 KTS AND GUSTS INCREASING TO
22-28 KTS DURING SAT MORNING AFTER 14Z.
DISCUSSION...UPDATED 18Z...
LARGE HIGH PRESSURE OF 1028 MB...OFF THE NC COAST AT MIDDAY...WILL
CONTINUE TO BRING FAIR WEATHER TO THE AREA THROUGH TONIGHT. A SHORT WAVE
TROF OVER THE MID/LOWER MS VALLEY HAS MID LEVEL CLOUDS FROM CHICAGO METRO
SE AND THESE CLOUDS TO CONTINUE TO DECREASE FROM NW TO SE DURING THIS
AFTERNOON. WITH SOME SUNSHINE APPEARING/DAYTIME HEATING AND MIXING...
EXPECT A FEW GUSTS TO 15-19 KT THIS AFTERNOON. ATMOSPHERE WILL DECOUPLE
LATE AFTERNOON/EARLY EVENING AGAIN AS INVERSION REDEVELOPS WITH SW WINDS
VEERING SSE AS WINDS DROP BELOW 10 KTS TONIGHT. STRONG SURFACE LOW
PRESSURE EMERGING OVER THE NORTHERN PLAINS DURING SAT TO INCREASE PRESSURE
GRADIENT OVER NE IL ALONG WITH SOUTH WINDS INCREASING FROM 12-17 KTS AND
WIND GUSTS INCREASING FROM 22-28 KTS AFTER 14Z SAT. THINK LOW LEVEL WIND
SHEAR LATE TONIGHT AND EARLY SAT MORNING WILL BE FOCUSED SW OF NE IL AS
2-3K FT WINDS INCREASE BETWEEN 30-40 KTS. BY SATURDAY MORNING...SOUTHERLY
LOW LEVEL FLOW FROM 2-3K FT WILL INCREASE TO 30-40 KTS. THIS WILL ADVECT
GULF MOISTURE NORTHWARD. MOS GUIDANCE SUGGEST MVFR CIGS ARRIVING BY
DAYBREAK SATURDAY...AND POSSIBLY LOWERING TO IFR BY MID SAT MORNING.
SHOWERS AND ISOLATED THUNDERSTORMS SHOULD MOSTLY HOLD OFF UNTIL SAT
AFTERNOON THOUGH COULD REACH RFD AS EARLY AS 17Z AND CHICAGO TAF SITES
AFTER 18Z SAT.
OUTLOOK...SOUTH WINDS INCREASING TO 20 TO 30 MPH SATURDAY
AFTERNOON WITH SHOWERS LIKELY AND POSSIBLY A THUNDERSTORM.
ALLSOPP/07
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM CONFIDENCE IN MVFR/IFR CIGS DEVELOPING SATURDAY MORNING.
* MEDIUM CONFIDENCE OF WIND GUSTS AND DIRECTION THIS AFTERNOON AND
SATURDAY.
* LOW TO MEDIUM CONFIDENCE TIMING AND COVERAGE OF SHOWERS AND ISOLATED
THUNDERSTORMS AT ORD SATURDAY AFTERNOON.
ALLSOPP/MTF
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 18Z...
SATURDAY NIGHT...SHOWERS AND SLIGHT CHANCE OF THUNDERSTORMS.
STRONG SOUTH WINDS OF 20-30 KT. MVFR LIKELY AND IFR POSSIBLE.
SUNDAY...SHOWERS AND CHANCE OF THUNDERSTORMS. STRONG SOUTH
WINDS BECOMING SOUTHWEST WITH GUSTS AT 25-35 KT AND POSSIBLY UP TO
40 KTS WITH THUNDERSTORMS. MVFR LIKELY AND IFR POSSIBLE.
MONDAY...MVFR CIG POSSIBLE. NORTHWEST WIND GUSTS OF 20 TO 25 KT.
TUESDAY-THURSDAY...VFR.
ALLSOPP/07
&&
.MARINE...
205 AM CST
A VERY ACTIVE PERIOD OF WEATHER IN STORE FOR LAKE MICHIGAN THROUGH
MONDAY WITH A COUPLE PERIODS OF GALE FORCE WINDS EXPECTED. LARGE
SPRAWLING HIGH PRESSURE CENTERED OFF THE COAST OF THE CAROLINAS THIS
MORNING WILL KEEP LIGHT TO MODERATE SOUTHWEST FLOW OVER THE LAKE
TODAY AND TONIGHT. THE HIGH WILL REMAIN JUST OFF THE COAST THROUGH
THE WEEKEND. MEANWHILE LOW PRESSURE WILL DEVELOP OVER THE CENTRAL
PLAINS TODAY AND TONIGHT. THIS LOW WILL DEEPEN AS IT MOVES NORTHEAST
INTO MINNESOTA BY SATURDAY EVENING. THIS WILL RESULT IN A PERIOD OF
SOUTHERLY GALES FOR THE LENGTH OF THE LAKE...MAINLY SATURDAY
AFTERNOON AND SATURDAY NIGHT. IN THE WAKE OF THIS FIRST LOW WINDS
MAY EASE A BIT SUNDAY MORNING. HOWEVER A SECOND LOW WILL FORM IN THE
PLAINS SATURDAY NIGHT. THIS LOW WILL DEEPEN AS IT MOVES NORTHEAST
TO NORTH OR CENTRAL LAKE MICHIGAN SUNDAY EVENING. SOUTH TO
SOUTHWEST WINDS ARE EXPECTED TO REMAIN AROUND 30 KNOTS
SUNDAY...BUT A PERIOD OF GALES IS POSSIBLE SUNDAY AFTERNOON. THERE
IS STILL SOME UNCERTAINTY ON THE TIMING AND STRENGTH OF THIS
SECOND LOW...SO WILL HOLD ON TO GALE WATCH AS IS...JUST INTO SUNDAY
MORNING FOR NOW...BUT WATCH/WARNING MAY NEED TO BE EXTENDED TO
SUNDAY AFTERNOON OR EVENING.
AS THE LOW CONTINUES TO DEEPEN AND MOVE NORTHEAST INTO QUEBEC
LATER SUNDAY NIGHT AND MONDAY...A PERIOD OF WEST TO NORTHWEST
GALES IS EXPECTED. HIGH PRESSURE WILL FINALLY BRING A QUIETER
PATTERN TO THE AREA FOR THE MIDDLE OF NEXT WEEK.
FOR THE NEARSHORE WATERS...NO HEADLINES AT THIS TIME...HOWEVER A
SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED BY SATURDAY AFTERNOON.
WITH OFFSHORE WINDS...DONT ANTICIPATE A GALE WOULD BE NEEDED FOR THE
NEARSHORE WATERS...UNTIL POSSIBLY SUNDAY AFTERNOON AS WINDS OVER
LAND MAY BE GUSTING TO NEAR 35 KTS.
ALLSOPP
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...9 AM SATURDAY TO 9 AM
SUNDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1152 AM CST Fri Nov 15 2013
.DISCUSSION...
ISSUED 901 AM CST Fri Nov 15 2013
A short-wave trough currently evident on water vapor imagery over
the mid/lower Mississippi River Valley is creating enough synoptic
lift across the region to produce plenty of mid-level cloudiness.
Despite a 12z KILX upper air sounding showing very dry air below
700mb, a few sprinkles/light showers have been reported across the
W/SW CWA around Jacksonville and Springfield. Radar returns are
moving to the NE, so expect scattered sprinkles across much of the
area for the remainder of the morning and perhaps lingering into
the early afternoon across the far E/NE. Have updated forecast to
significantly increase cloud cover and add morning sprinkles. Mild
afternoon highs in the lower to middle 50s still look good. Zone
update has already been issued.
Barnes
&&
.AVIATION...
ISSUED 1152 AM CST Fri Nov 15 2013
VFR conditions will continue through this evening, before MVFR
ceilings arrive later tonight into Saturday morning. Southerly
winds will bring increasing amounts of moisture northward into
the area over the next 24 hours. A weak upper-level disturbance
over the lower Mississippi River Valley is currently spreading
mid-level clouds across Illinois: however, these will begin to
clear from west to east across the area late this afternoon into
the evening. 17z/11am satellite imagery shows the clouds breaking
up across north-central Missouri, with satellite timing tools
bringing this partial clearing to KPIA and KSPI by around 21/22z.
Forecast soundings indicate mostly clear conditions this evening,
before better moisture and lower clouds arrive from the south
overnight. HRRR shows low clouds spreading northward after 05z,
with extrapolation suggesting MVFR ceilings of around 1500ft
arriving at the central Illinois terminals between 07z and 09z.
Southwesterly winds of 10 to 15kt this afternoon will decrease to
around 10kt tonight. As pressure gradient tightens, southerly
winds will increase markedly on Saturday, with gusts likely
exceeding 25kt. Showers associated with an approaching short-wave
will likely remain just west of the TAF sites until Saturday
afternoon: however, have included VCSH at KPIA after 15z in case
precip arrives sooner.
Barnes
&&
.PREV DISCUSSION...
ISSUED 323 AM CST Fri Nov 15 2013
High pressure sliding off the east coast and southerly return flow
pushing warmer air and plenty of moisture into the region,
essentially loading the atmosphere ahead of the next system
developing over the western half of the country. An active weekend
on tap for the Midwest as a low pressure system develops rapidly
over ILX. Showers and thunderstorms expected on Saturday and
Sunday...with best severe weather potential Sunday afternoon.
System will be moving quickly in rather progressive flow across
the country. Models are in decent agreement overall, though the
GFS remains the quick solution, with the NAM speeding up to join
the GFS, and the ECMWF lagging behind. In all fairness, the ECMWF
still maintains a neutral tilt to the synoptic trof up to mid day
Sunday and the development would be a little slower overall.
Forecast trending to the quicker solutions, and precip clearing
by the first of the week.
SHORT TERM...Today and tomorrow...
Temps a couple more degrees today, warming into the lower 50s for
most of the area with breezy southerly winds keeping the warm air
moving into the Midwest. Warming trend continues through the
overnight and into tomorrow, though the increasing moisture will
keep partly cloudy today...increasing through the night and
towards morning with the approach of the next system. Waves ahead
of the developing main sfc low ripple through the southwesterly
flow aloft as the synoptic trof digs out over the SW. Precip
chances start to spread over the area for Saturday and Saturday
night. Starting to mention a slight chance for thunder on Saturday
night as the upper level dynamics get going. Best chances,
however, will be on Sunday.
LONG TERM...Sunday through Thursday...
Models tightening up on the timing of the front and main sfc low
Sun afternoon/evening, even with the ECMWF starting to catch up.
Faster solution was the winner with the last system, and seems to
be the consensus for this one as well in quite progressive flow
across the country. NAM/GFS both going negative tilt with the wave
aloft, which is reflected in the more explosive development of the
low. The system ramps up almost overhead and the chance for severe
weather will be a very quick window of opportunity with the possibility for
rapid development. This system will be moving fast. That being
said, plenty of warm and wet conditions out ahead of the cold
front and upper level dynamics providing plenty of lift. Severe
threat already in the Day 3, mainly east of Interstate 55. With
diffluence aloft ahead of front and depth and strength of vertical
shear, will have to watch preceding activity closely. Previous
showers/thunderstorms may limit instability in the boundary
layer ahead of the front. For now, going ahead and putting in
categorical pops east of I55 for Sun afternoon.
System should clear out quickly and cooler airmass recovering over
the region for the start of the work week. Temperatures returning
to more seasonal conditions with a dry forecast through next week.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1007 PM EST SAT NOV 16 2013
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 138 PM EST SAT NOV 16 2013
A POTENT AND STRENGTHENING LOW PRESSURE SYSTEM WILL LIFT NORTHEAST
OVER THE WESTERN GREAT LAKES LATE SUNDAY. AN ASSOCIATED STRONG COLD
FRONT WILL SWEEP EAST ACROSS CENTRAL INDIANA SUNDAY AFTERNOON AND
EVENING. INCREASING MOISTURE STREAMING NORTHWARD AHEAD OF THE FRONT
WILL INTERACT WITH THE FRONT AND RESULT IN WIDESPREAD SHOWERS AND
ALSO THUNDERSTORMS TONIGHT THROUGH SUNDAY EVENING. THERE IS ALSO A
MODERATE RISK OF SEVERE WEATHER SUNDAY AND SUNDAY EVENING WITH
DAMAGING WINDS THE MAIN THREAT ALONG WITH HAIL AND ISOLATED
TORNADOES. HIGH PRESSURE WILL BUILD IN NEXT WEEK WITH DRY CONDITIONS
AND NORMAL TO BELOW NORMAL TEMPERATURES. THE NEXT CHANCE OF SHOWERS
WILL BE LATE IN THE WEEK AND INTO THE WEEKEND AS ANOTHER COLD FRONT
TAKES AIM AT THE OHIO VALLEY.
&&
.NEAR TERM /OVERNIGHT/...
ISSUED AT 1007 PM EST SAT NOV 16 2013
RAIN SHOWERS BECOME MORE ORGANIZED AND INCREASING IN COVERAGE
ACROSS THE WESTERN HALF OF THE FORECAST AREA THIS EVENING AS
STRONG LOW LEVEL JET APPROACHES FROM THE WEST. WINDS HAVE STEADILY
INCREASED THROUGH THE EVENING...WITH GUSTS TO 20-25MPH BECOMING
MORE COMMON. TEMPS REMAINED PRIMARILY IN THE UPPER 50S AT 0230Z.
EVENING SURFACE ANALYSIS INDICATING AN OCCLUDING LOW PRESSURE
SYSTEM OVER MINNESOTA WITH A SECONDARY LOW EJECTING INTO THE
CENTRAL PLAINS. A SUBTLE WARM FRONT EXTENDING FROM THE OCCLUDED
LOW ACROSS CENTRAL ILLINOIS AND SOUTHWEST INDIANA WILL LIFT NORTH
ACROSS THE FORECAST AREA OVERNIGHT. BROAD 55-60KT 850MB JET WILL
TRANSPORT DEEP MOISTURE INTO THE REGION TONIGHT...WITH
MESOANALYSIS INDICATING A PLUME OF 1.2-1.4 IN PRECIP WATER VALUES
POISED TO EXPAND ACROSS THE FORECAST AREA WITHIN THE NEXT FEW
HOURS. BOTH THE HRRR AND THE WRF-NMM BOTH CONSISTENT IN EXPANDING
PRECIP OVER CENTRAL INDIANA INTO THE OVERNIGHT...WITH WIDESPREAD
RAIN FROM 06-12Z. COULD SEE LOCALLY HEAVY RAINFALL CONSIDERING THE
HIGH PRECIP WATER VALUES WITH POTENTIAL FOR MANY LOCATIONS TO PICK
UP 0.50 TO 1 INCH OVERNIGHT.
SEEING A SLOW EXPANSION IN LIGHTNING STRIKES OVER THE MID
MISSISSIPPI VALLEY AS WELL AS ELEVATED INSTABILITY INCREASES. WILL
CONTINUE WITH THE ISOLATED THUNDER MENTION OVERNIGHT. SURFACE
BASED CONVECTION SHOULD REMAIN TO THE WEST OF THE WABASH RIVER
THROUGH DAYBREAK. POTENTIAL DOES EXIST LATE TONIGHT FOR A FEW
STRONGER STORMS TO PRODUCE HAIL...ESPECIALLY OVER THE LOWER
WABASH VALLEY...BUT OVERALL ANTICIPATE CONVECTION TO REMAIN
SUBSEVERE THROUGH 12Z.
ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
ISSUED AT 138 PM EST SAT NOV 16 2013
OBVIOUS FOCUS FOR THE SHORT TERM WILL BE ON SEVERE WEATHER POTENTIAL
ON SUNDAY AND SUNDAY EVENING AS A CLASSIC FALL SEVERE WEATHER
OUTBREAK LOOKS MORE AND MORE LIKELY WITH DAMAGING WINDS THE MAIN
THREAT...BUT TORNADOES CERTAINLY ARE A CONCERN AS WELL.
MODELS ARE NOW IN GOOD AGREEMENT THAT PACIFIC NORTHWEST TROUGH WILL
BECOME NEGATIVELY TILTED ON SUNDAY CAUSING RAPID INTENSIFICATION OF
A SURFACE LOW PRESSURE SYSTEM. DEEPENING SURFACE LOW WILL LIFT TO
NORTHWEST LOWER MICHIGAN OR THE NORTHERN WATERS OF LAKE MICHIGAN BY
00Z MONDAY. ASSOCIATED COLD FRONT WILL THEN SWEEP QUICKLY EAST
ACROSS CENTRAL INDIANA FROM AROUND 18Z SUNDAY TO 00Z MONDAY. PRIOR
TO THAT...A STALLED COLD FRONT IS EXPECTED TO RETURN NORTH AS A WARM
FRONT ACROSS CENTRAL INDIANA AROUND 12-16Z SUNDAY. UPPER SPEED MAX
TO AROUND 120 KNOTS AROUND THE BASE OF THE TROUGH ALONG WITH
WEAKENING...BUT STILL FORMIDABLE OHIO VALLEY UPPER JET WILL PROVIDE
BROAD DILUENT FLOW ON TOP OF WARM CONVEYOR BELT/60 PLUS KNOT LOW
LEVEL JET AHEAD OF THE COLD FRONT. VERY STRONG WIND SHEAR /40 KNOTS
OR MORE FROM 1000-700 MILLIBARS AND 60 KNOTS OR MORE FROM 1000-500
MILLIBARS/ ALONG WITH LONG CURVED HODOGRAPHS AND VERY HIGH HELICITY
NUMBERS OVER 300 METERS SQUARED PER SECONDS SQUARED WILL PROVIDE
AMPLE SPIN IN THE ATMOSPHERE FOR TORNADIC ACTIVITY GIVEN ENOUGH
INSTABILITY.
REGARDING INSTABILITY...TEMPERATURES IN THE UPPER 60S TO MID 70S
WITH WARM ADVECTION ALONE...DEW POINTS APPROACHING 60
DEGREES...700-500 MILLIBAR LAPSE RATES TO 6 DEGREES CELSIUS PER
KILOMETER OR MORE AND DRY INTRUSION ALOFT SHOULD RESULT IN AT LEAST
SOME SURFACE INSTABILITY DESPITE EXPECTED THICK CLOUD COVER AND
EARLIER OR ONGOING OVERNIGHT AND MORNING CONVECTION. EVEN THE LESS
UNSTABLE...12Z DETERMINISTIC GFS IS NOW FORECASTING 500 J/KG CAPE OR
MORE DURING THE AFTERNOON HOURS BUT WEAKENING SIGNIFICANTLY AFTER
DARK.
BASED ON THE ABOVE...AGREE WITH SPC DAY2 MODERATE RISK AND EXPECT A
SEVERE WEATHER OUTBREAK SUNDAY MORNING THROUGH EARLY SUNDAY EVENING.
WILL HAVE TO WATCH OUT FOR DISCRETE SUPERCELLS ESPECIALLY DURING THE
MORNING NEAR THE SURFACE WARM FRONT AND AFTERNOON IN THE WARM SECTOR
THEN...WITH ELONGATED FRONTOGENESIS OCCURRING NEAR THE COLD
FRONT...SHOULD SEE LINEAR ACTIVITY MOVE THROUGH AROUND 18Z IN THE
NORTHWEST TO 00Z IN THE SOUTHEAST ALONG AND JUST AHEAD OF THE FRONT.
THIS WILL BE MORE OF A WIDESPREAD DAMAGING WIND THREAT BUT WITH ALSO
THE POTENTIAL FOR A FEW BRIEF SPIN UPS IN ANY CIRCULATION COUPLET.
HEAVY RAIN COULD ALSO BE AN ISSUE ESPECIALLY EARLY...BEFORE THE DRY
PUNCH ALOFT MOVES IN. IT WILL ALSO CONTINUE TO BE WINDY...BUT DO NOT
THINK THE HIGHER WINDS AT THE TOP OF THE BOUNDARY LAYER FROM THE
BUFKIT 12Z NAM WILL BE ABLE TO MIX DOWN WITHOUT SUNSHINE.
WILL CONTINUE WITH CATEGORICAL POPS PER MOS AND DROPPING
DRAMATICALLY AFTER 06Z MONDAY AND ALTOGETHER AFTER 06Z. THE REST OF
THE SHORT TERM WILL BE CHARACTERIZED BY DRY WEATHER WITH SLIGHTLY
BELOW NORMAL TEMPERATURES AS CANADIAN HIGH PRESSURE BUILDS IN BEHIND
THE COLD FRONT.
MOS HIGHS IN THE UPPER 40S TO LOWER 50S MONDAY AND ALLBLEND IN THE
40S ON TUESDAY LOOK GOOD. ALSO...SHOULD SEE PLENTY OF SUNSHINE...
ESPECIALLY TUESDAY AS THE HIGH PASSES OVERHEAD.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
ISSUED AT 219 PM EST SAT NOV 16 2013
MODELS CONTINUE TO HOLD ONTO HIGH PRESSURE EARLY IN THE LONG TERM
PERIOD...WITH A TREND TOWARD WETTER FORECASTS LATE IN THE WEEK AND
INTO THE WEEKEND. INITIALIZATION PROVIDED SLIGHT CHANCE TO LOW
CHANCE POPS FROM WEDNESDAY NIGHT ONWARD...AND CANNOT REALLY ARGUE
WITH IT...ALTHOUGH THE LENGTH OF TIME POPS ARE IN MAY BE A BIT
OVERDONE. THIS WILL BE REFINED AS THE WEEK WEARS ON.
QUASIZONAL FLOW MUCH OF THE PERIOD SUGGESTS TEMPS NEAR
CLIMATOLOGY...AND INITIALIZATION HANDLED THIS WELL.
&&
.AVIATION /DISCUSSION FOR THE 170300Z KIND TAF UPDATE/...
ISSUED AT 923 PM EST SAT NOV 16 2013
NO CHANGES MADE TO THE FORECAST AT THIS TIME. PREVIOUS DISCUSSION
FOLLOWS.
AN UPPER DISTURBANCE LIFTING OUT OF THE EASTERN KANSAS/WESTERN
MISSOURI AREA AT THIS TIME IS PROGGED BY THE SHORT TERM MODELS TO
PASS OVER THE SOUTHERN TIP OF LAKE MICHIGAN TOWARDS/AFTER 170600Z.
THIS DISTURBANCE...COUPLED WITH LIFT ALONG A STRONG LOW LEVEL JET
AND A PLUME OF STEEPER MID LEVEL LAPSE RATES ADVECTING INTO THE
AREA...SUGGEST AT LEAST SCATTERED CONVECTION SHOULD DEVELOP IN THE
VICINITY OF THE TAF SITES AFTER ABOUT 170500Z. CONVECTIVE PARAMETERS
OFF THE MODELS ARE PRETTY HIGH...SO THINK THE POTENTIAL FOR
CONVECTION DIRECTLY IMPACTING THE TAF SITES AT SOME POINT LATE
TONIGHT IS PRETTY GOOD. BEST ESTIMATES ON TIMING AT THIS TIME ARE
FROM ROUGHLY 170500Z TIL ABOUT SUNRISE ON SUNDAY. BRIEF PERIODS OF
IFR VISIBILITY RESTRICTIONS EXPECTED WITHIN THE HEAVIER CELLS.
OTHERWISE...GIVEN THE 55-60KT LOW LEVEL JET...THERE IS CONCERN FOR
LOW LEVEL WIND SHEAR TOWARDS/AFTER 170600Z AS THE CORE OF THE JET
MOVES OVERHEAD. AT THIS POINT...IT APPEARS THE BOUNDARY LAYER SHOULD
REMAIN MIXED UP ENOUGH TO PREVENT THE NOCTURNAL INVERSION FROM FULLY
DEVELOPING...GIVEN THE INCREASING WINDS/EXPECTED CONVECTION. WILL
LEAVE OUT WIND SHEAR AT THIS TIME DUE TO QUESTIONS REVOLVING AROUND
THE DEVELOPMENT OF THE NOCTURNAL INVERSION...BUT WILL MONITOR THINGS
AS THE EVENING GOES ON.
OUTSIDE OF ANY CONVECTION...EXPECTING CEILINGS GENERALLY AROUND 020
TONIGHT ALONG WITH SOME SURFACE GUSTS UP TO 22 KTS FROM 160-180
DEGREES.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM NOON TO 9 PM EST SUNDAY FOR INZ021-028>031-
035>049-051>057-060>065-067>072.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM....NIELD
AVIATION...JAS
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS TOPEKA KS
303 PM CST Fri Nov 15 2013
.SHORT TERM...(This Evening through Saturday)
Issued at 250 PM CST FRI NOV 15 2013
On Friday afternoon, an upper trough was located over southern
California and Nevada while a series of weaker lead short wave
troughs were moving through fairly fast west southwest flow aloft
from the four counters into the western Plains. At the surface, low
pressure was deepening in eastern Colorado with intensifying
pressure gradient and southerly flow from southern Texas through the
Dakotas. A pool of quality low level moisture was in place across
northeast Texas and moving into eastern Oklahoma. As the lee surface
low continues to deepen overnight, expect a strong low level jet to
transport this moisture into eastern Kansas with a west to east
gradient while a strong elevated mixed layer and warm advection
builds above the moist boundary layer. The moist advection will
likely occur after a fairly quick evening cool down owing to mostly
clear skies, and the influx of moisture into cooler air along with
fairly strong ascent overnight and dry air aloft may contribute to
periods of drizzle during the early morning hours. There are also
some indications of moistening around 10 thousand feet which may
lead to weak elevated instability and at least some potential for a
few showers given the magnitude of lift. Winds at the surface will
also increase through the night as the pressure gradient strengthens.
Any light shower activity and drizzle will likely come to an end by
late Saturday morning as boundary layer mixing increases and
elevated capping increases. As mixing increases, the low level jet
will begin to mix gusts to the surface. The LLJ is forecast to have
50+ kt winds at 2500 feet AGL which would easily translate 45+ mph
wind gusts to the surface on a clear day, but the stratus deck may
be sufficient to limit overall mixing a bit, and by the time
clearing is forecast to occur, the LLJ will have weakened a bit. The
main question today is whether the depth of mixing will matter given
the strength of winds even 1500 feet AGL and the very strong late
morning pressure gradient. For now, have not issued a wind advisory,
but could certainly see the need to do so if future model guidance
suggests the 12Z NAM and recent RAP runs that highlight an even
stronger low level wind field. It`s a low confidence wind forecast
at this time that could result in peak gusts somewhere between 40
mph and 55 mph, with the strongest winds focused in east central KS.
By late afternoon, another lead short wave will approach the area.
At least partial afternoon clearing should have occurred with
temperatures in the lower 70s and dewpoints in the upper 50s. While
a strong capping inversion will be in place for much of the day, it
appears that the incoming trough will help cool the cap such that
afternoon CINH may decrease into the 10 to 50 J/KG range for a short
period between roughly 3 PM and 7 PM before rapidly increasing
again. Higher Res model guidance suggests MLCAPE in the 500 to 1000
J/KG range during this period while 0-6 km shear is 40 to 60 kts.
While these conditions would normally suggest some potential for a
few strong storms, the primary limiting factor...even with the
incoming short wave trough...is a general lack of any meaningful
surface convergence with the southwesterly low level wind field. The
lack of low level forcing along with a lopsided shear/CAPE balance
suggests it will be difficult to sustain any updrafts. At this time,
will maintain a slight chance of thunderstorms in the eastern parts
of KS generally east of Marysville to Burlington, and if one should
develop it would warrant an attentive eye.
.LONG TERM...(Saturday Night through Friday)
Issued at 250 PM CST FRI NOV 15 2013
By Saturday evening as the boundary layer begins to cool the
southwesterly low level jet increases which will ultimately
strengthen the capping inversion. The increasing low level jet
during the evening forces drier air into the lower levels. If an
elevated storm is able to form after sunset the dry air intrusion
should hinder any persistence. All of these factors should work
against any sustained storm threat across the area...therefore went
with a dry forecast after 00z Sun. Gusty winds continue for the
southeast half of the cwa and especially southeast of the turnpike
overnight Saturday into Sunday. Low temperatures range from the mid
40s in north central KS to the mid 50s in east central KS.
On Sunday morning the main upper level trough axis passes through
the region as well as the associated cold front. The cold front
should clear the area by 15z Sun with a significant drop in dew
points following the passage. Behind the main trough axis
northwesterly flow increases in response to the deepening pressure
field across the upper Midwest as the system becomes negatively
tilted. Forecast soundings show most locations mixing between 800 to
700 mb especially across central KS where dew points are lower. Red
flag criteria is possible Sunday during the day across the western
portions of the area with winds gusting to around 35 mph in
combination with the low relative humidity. Less certain is the
effect cooler air behind the front has on temperatures and how low
the dew points get Sunday afternoon determining min RH. Therefore
did not issue any headlines and will let later shifts evaluate the
latest guidance. High temperatures on Sunday look to reach the upper
50s to low 60s.
In the wake of that system dry northwest mid level flow sets up for
the central US allowing surface high pressure to build into the
region. Winds should begin to decrease Sunday evening with a
relatively calm day in store for Monday. The mid level flow quickly
transitions to a zonal pattern and return flow develops as the high
pressure retreats then the models really start to disagree by mid
week. The 12z ECMWF/GEM suggesting precip chances by Wed as a
shortwave pushes a front through the region, but this lacks any
consistency at this point therefore kept the forecast dry. Although
the better chances for precip appear to be on Thurs and Fri as a
trough approaches from the west coast. The evolution of that system
and the associated surface features is unknown. Have added the
possibility of snow Thurs night and Friday which is advertised by
the 12z ECMWF but confidence is pretty low. Through the extended
temperatures remain near average with highs in the 50s and lows in
the 30s with a cooling trend late in the period.
&&
.AVIATION...(For the 18Z TAFs through 18Z Saturday Afternoon)
Issued at 1133 AM CST FRI NOV 15 2013
Intensifying low pressure over the next 24 hours will bring
increasing wind speeds and a surge of moisture. This moisture
should result in IFR, or even LIFR ceilings at TAF sites, with an
expected arrival time between 05Z and 08Z and persisting through
14Z or so with a gradual lift to broken MVFR cigs. Is also some
potential for reduced vis with the moisture surge with a small
chance for 1/2SM or less, and even some dz or shra. MHK will be
on the western fringe of the moisture, with less confidence in the
ceilings building overhead. If so, will see persistent IFR but if
not, should have VFR through the TAF. South winds will increase
steadily from 00Z through 18Z with gusts to 35 kts or greater
possible by late Saturday morning.
Barjenbruch
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Barjenbruch
LONG TERM...Sanders
AVIATION...Barjenbruch
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1158 PM MST THU NOV 14 2013
.UPDATE...
ISSUED AT 839 PM MST THU NOV 14 2013
LIGHT WINDS STILL IN PLACE OVER THE SOUTHEAST THIRD OF THE AREA AT
THIS TIME. TEMPERATURES IN THIS AREA WERE APPROACHING FORECAST
MINS. OVER THE REMAINDER OF THE AREA SOUTH WINDS HAVE INCREASED
AND HAVE SLOWED THE TEMPERATURE FALL. SO LOWERED THE MINS IN THE
SOUTHEAST PORTION AND ADJUSTED THE WINDS BASED ON THE LATEST
OBSERVATIONS AND MESOSCALE GUIDANCE.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH FRIDAY)
ISSUED AT 1251 PM MST THU NOV 14 2013
LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOW SHORTWAVE TROUGH ACROSS
WESTERN KS. SUBSIDENCE/DRYING ASSOCIATED WITH SHORTWAVE RIDGE
IMMEDIATELY BEHIND THE TROUGH AXIS IS SPREADING EAST OVER OUR CWA.
ANOTHER SHORTWAVE TROUGH IS IN PLACE ACROSS THE PAC NW WITH MID-HIGH
LEVEL MOISTURE PLUME OVER THE NORTHERN ROCKIES. AT THE SURFACE A
COLD FRONT THAT PUSHED ACROSS OUR CWA THIS MORNING IS NOW OVER
CENTRAL KANSAS EXTENDING SOUTH ACROSS THE TEXAS/OKLAHOMA PANHANDLES.
SURFACE HIGH PRESSURE IS IN PLACE ACROSS OUR CWA WITH CLEAR SKIES AND
SEASONAL TEMPS IN THE MID-UPPER 50S.
WITH DRY LAYER AND ONLY PASSING HIGH CLOUDS TO THE NORTH...THE
PRIMARY CONCERN IN THE SHORT TERM WILL BE POSSIBLE RFW CONDITIONS ON
FRIDAY AFTERNOON. AS SHORTWAVE RIDGE SHIFTS EAST AND UNIDIRECTIONAL
SW FLOW DEVELOPS ACROSS CWA WAA WILL BRING ABOVE NORMAL TEMPS BACK
TO OUR AREA...ALONG WITH DRY/WINDY CONDITIONS. I FOLLOWED THE
PREVIOUS FORECAST TREND AND BUMPED TEMPS UP A LITTLE FRIDAY
AFTERNOON...WITH WARMEST TEMPS LIKELY IN THE SOUTHERN PART OF OUR
CWA WHERE HIGHS AROUND 70F ARE LIKELY.
MODEL SOUNDINGS WOULD INDICATE GOOD MIXING HEIGHTS...SUPPORTING LOW
TD VALUES DURING THE AFTERNOON. I WAS CONSERVATIVE IN HOW LOW I
WENT...BUT STILL ENDED UP WITH TD VALUES IN THE TEENS ACROSS EASTERN
COLORADO. WARM TEMPS AND LOW DEWPOINTS WILL SUPPORT RH VALUES AT
LEAST IN THE 15-20 PERCENT RANGE...AND WITH GUSTY WINDS IT LOOKS
LIKE WE COULD SEE RFW CRITERIA MET AT LEAST ACROSS THE SW QUADRANT
OF OUR CWA. FURTHER NORTH AND EAST I AM NOT AS CONFIDENT IN MEETING
CRITERIA. IT IS HARD TO SAY IF WE WILL GET A FULL 3HR OF RFW
CRITERIA ACROSS THE SOUTHWEST SO I DECIDED TO START WITH A FIRE
WEATHER WATCH DURING THIS FORECAST CYCLE.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 1150 PM MST THU NOV 14 2013
ZONAL FLOW WILL BE IN PLACE ACROSS MOST OF THE CONUS FOR THE
PERIOD MONDAY THROUGH WEDNESDAY. TEMPERATURES WILL START OFF COOL
ON MONDAY BUT QUICKLY WARM TO NEAR OR EVEN SLIGHTLY ABOVE NORMAL
FOR TUESDAY AND WEDNESDAY. NO PRECIPITATION IS EXPECTED. THE NEXT
SYSTEM WILL ARRIVE THURSDAY OR FRIDAY DEPENDING ON WHICH MODEL YOU
PICK...WITH THE GFS AT LEAST 12 HOURS FASTER WITH A STRONG COLD
FRONT COMPARED TO THE ECMWF. SO THURSDAY COULD SEE A SIGNIFICANT
COOL DOWN WITH THE FRONT...OR PREFRONTAL WARMING AHEAD OF IT...AND
WITH NO CLEAR CHOICE ACCEPTED A COMPROMISE BETWEEN THE TWO. EITHER
WAY...MUCH COLDER SHOULD ARRIVE BY THURSDAY NIGHT AND FRIDAY. ANY
PRECIPITATION WITH THE SYSTEM WILL BE ON THE LIGHT SIDE AS THE
BEST UPPER FORCING WILL SLIDE WELL SOUTH OF THE CENTRAL HIGH
PLAINS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1008 PM MST THU NOV 14 2013
VFR CONDITIONS EXPECTED THROUGH THE PERIOD WITH ONLY VARIABLE
AMOUNTS OF CIRRUS THROUGH THE PERIOD. LIGHT SOUTHERLY WINDS STILL
EXPECTED TO INCREASE DURING THE MID AND LATE MORNING HOURS TO NEAR
20 KNOTS SUSTAINED WITH GUSTS IN THE 25 TO 30 KNOT RANGE. WINDS
BECOME LIGHT ONCE AGAIN TOWARD SUNSET.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...FIRE WEATHER WATCH FROM 11 AM MST FRIDAY THROUGH FRIDAY
AFTERNOON FOR KSZ013-027-041.
CO...FIRE WEATHER WATCH FROM 11 AM MST FRIDAY THROUGH FRIDAY
AFTERNOON FOR COZ253-254.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...DR
LONG TERM...024
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1010 PM MST THU NOV 14 2013
.UPDATE...
ISSUED AT 839 PM MST THU NOV 14 2013
LIGHT WINDS STILL IN PLACE OVER THE SOUTHEAST THIRD OF THE AREA AT
THIS TIME. TEMPERATURES IN THIS AREA WERE APPROACHING FORECAST
MINS. OVER THE REMAINDER OF THE AREA SOUTH WINDS HAVE INCREASED
AND HAVE SLOWED THE TEMPERATURE FALL. SO LOWERED THE MINS IN THE
SOUTHEAST PORTION AND ADJUSTED THE WINDS BASED ON THE LATEST
OBSERVATIONS AND MESOSCALE GUIDANCE.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH FRIDAY)
ISSUED AT 1251 PM MST THU NOV 14 2013
LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOW SHORTWAVE TROUGH ACROSS
WESTERN KS. SUBSIDENCE/DRYING ASSOCIATED WITH SHORTWAVE RIDGE
IMMEDIATELY BEHIND THE TROUGH AXIS IS SPREADING EAST OVER OUR CWA.
ANOTHER SHORTWAVE TROUGH IS IN PLACE ACROSS THE PAC NW WITH MID-HIGH
LEVEL MOISTURE PLUME OVER THE NORTHERN ROCKIES. AT THE SURFACE A
COLD FRONT THAT PUSHED ACROSS OUR CWA THIS MORNING IS NOW OVER
CENTRAL KANSAS EXTENDING SOUTH ACROSS THE TEXAS/OKLAHOMA PANHANDLES.
SURFACE HIGH PRESSURE IS IN PLACE ACROSS OUR CWA WITH CLEAR SKIES AND
SEASONAL TEMPS IN THE MID-UPPER 50S.
WITH DRY LAYER AND ONLY PASSING HIGH CLOUDS TO THE NORTH...THE
PRIMARY CONCERN IN THE SHORT TERM WILL BE POSSIBLE RFW CONDITIONS ON
FRIDAY AFTERNOON. AS SHORTWAVE RIDGE SHIFTS EAST AND UNIDIRECTIONAL
SW FLOW DEVELOPS ACROSS CWA WAA WILL BRING ABOVE NORMAL TEMPS BACK
TO OUR AREA...ALONG WITH DRY/WINDY CONDITIONS. I FOLLOWED THE
PREVIOUS FORECAST TREND AND BUMPED TEMPS UP A LITTLE FRIDAY
AFTERNOON...WITH WARMEST TEMPS LIKELY IN THE SOUTHERN PART OF OUR
CWA WHERE HIGHS AROUND 70F ARE LIKELY.
MODEL SOUNDINGS WOULD INDICATE GOOD MIXING HEIGHTS...SUPPORTING LOW
TD VALUES DURING THE AFTERNOON. I WAS CONSERVATIVE IN HOW LOW I
WENT...BUT STILL ENDED UP WITH TD VALUES IN THE TEENS ACROSS EASTERN
COLORADO. WARM TEMPS AND LOW DEWPOINTS WILL SUPPORT RH VALUES AT
LEAST IN THE 15-20 PERCENT RANGE...AND WITH GUSTY WINDS IT LOOKS
LIKE WE COULD SEE RFW CRITERIA MET AT LEAST ACROSS THE SW QUADRANT
OF OUR CWA. FURTHER NORTH AND EAST I AM NOT AS CONFIDENT IN MEETING
CRITERIA. IT IS HARD TO SAY IF WE WILL GET A FULL 3HR OF RFW
CRITERIA ACROSS THE SOUTHWEST SO I DECIDED TO START WITH A FIRE
WEATHER WATCH DURING THIS FORECAST CYCLE.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 157 PM MST THU NOV 14 2013
INTI AL CONCERN FOR THE PERIOD WILL CENTER AROUND PRECIPITATION
CHANCES AS A SERIES OF LOW AMPLITUDE SHORT WAVE TROUGHS MOVE
AROUND THE BASE OF LARGE SCALE TROUGH THAT DIGS INTO THE AREA ON
SUNDAY. MODELS SEEM TO BE TRENDING DRIER AND DRIER WITH THESE
SYSTEMS AND WITH LATEST SREF AND GEFS DATA BACKING OFF OF POP
VALUES...THINK LOWERING POPS TO 10 PERCENT OR LESS WARRANTED AT
THIS TIME. AM CONCERNED ABOUT THE PERIOD OF STRONG FRONTAL SCALE
FORCING AND POTENTIAL INSTABILITY...BUT WITH DRY PROFILES AND
AFOREMENTIONED PROBABILISTIC FORECASTS...DO NOT THINK REALIZATION
OF INSTABILITY IS VERY LIKELY TO OCCUR.
OTHER CONCERN WILL BE POTENTIAL FOR STRONG WINDS DEVELOPING ACROSS
MUCH OF THE AREA ON SUNDAY. MODELS GENERALLY AGREE THAT TIGHT
HEIGHT GRADIENT WILL BE IN PLACE ACROSS THE AREA AS TROUGH SAGS TO
THE SOUTH...RESULTING IN STRONG WINDS JUST OFF THE SURFACE. AM NOT
EXPECTING WARNING LEVEL WINDS...BUT POTENTIAL APPEARS TO BE
INCREASING FOR ADVISORY TYPE WINDS IN THE AFTERNOON.
IN THE EXTENDED (SUN NIGHT-THURSDAY)...BRIEF PERIOD OF SHORT WAVE
RIDGING EXPECTED BEFORE A ZONAL/PROGRESSIVE PATTERN DEVELOPS ACROSS
THE AREA THROUGH THE REST OF THE WEEK. DOES NOT APPEAR TO BE MUCH
THREAT FOR PRECIPITATION DURING THIS PERIOD...WITH SOMEWHAT
PERSISTENT LEE TROUGH LEADING TO PREDOMINATELY WARM SOUTHERLY
FLOW. POTENTIAL FOR THICK MOUNTAIN CIRRUS DUE TO STRONG CROSS
MOUNTAIN FLOW LIMITS CONFIDENCE ON HOW WARM THINGS WILL GET...BUT
CONTINUED WARMING TREND LOOKS TO BE IN ORDER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1008 PM MST THU NOV 14 2013
VFR CONDITIONS EXPECTED THROUGH THE PERIOD WITH ONLY VARIABLE
AMOUNTS OF CIRRUS THROUGH THE PERIOD. LIGHT SOUTHERLY WINDS STILL
EXPECTED TO INCREASE DURING THE MID AND LATE MORNING HOURS TO NEAR
20 KNOTS SUSTAINED WITH GUSTS IN THE 25 TO 30 KNOT RANGE. WINDS
BECOME LIGHT ONCE AGAIN TOWARD SUNSET.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...FIRE WEATHER WATCH FROM FRIDAY MORNING THROUGH FRIDAY AFTERNOON
FOR KSZ013-027-041.
CO...FIRE WEATHER WATCH FROM FRIDAY MORNING THROUGH FRIDAY AFTERNOON
FOR COZ253-254.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...DR
LONG TERM...JRM
AVIATION...BULLER
AREA FORECAST DISCUSSION...CORRECTED
NWS CARIBOU ME
1255 AM EST FRI NOV 15 2013
.SYNOPSIS...
HIGH PRESSURE WILL SLOWLY MOVE OFF THE EAST COAST THROUGH FRIDAY
AS A RAPIDLY MOVING WEATHER DISTURBANCE SLIDES EAST THROUGH
QUEBEC. HIGH PRESSURE WILL REBUILD ACROSS MAINE AND THE MARITIMES
THIS WEEKEND.&&
.NEAR TERM /THROUGH TODAY/...
1245 AM UPDATE...STRATUS DECK ACROSS NRN NEW ENGLAND CONTINUES TO
BE THE MAIN FORECAST CONCERN FOR THE NEAR TERM. THERE IS A PRETTY
STRONG GRADIENT FROM CLOUDY TO MOSTLY CLEAR FROM CALAIS WWD TO
DEXTER. BOTH THE NAM AND RAP INDICATE THAT THE BACK EDGE OF THIS
STRATUS SHOULD CONTINUE TO MOVE NORTH THIS MORNING. THE STRATUS
WILL BECOME MORE OF A STRATOCU DECK ACROSS OUR NRN ZONES TODAY...WITH
SOME BREAKS IN THE CLOUD COVER DEVELOPING. FURTHER SOUTH...SKIES
WILL BE PARTLY TO MOSTLY SUNNY. TEMPS IN THE CLEAR AREAS WILL
GENERALLY BE IN THE 20S EARLY THIS MORNING...WITH 30S IN THE
CLOUDY AREAS. TEMPS SHOULD WARM INTO THE 40S FOR HIGH TEMPS THIS
AFTERNOON...WITH LOWER 50S POSSIBLE ACROSS THE SRN THIRD OF THE
FCST AREA.
940 PM UPDATE...THE STRATUS DECK CONTINUES TO SHIFT SLOWLY NORTH
AND AS OF 0230Z EXTENDS ON A LINE FROM ABOUT DOVER-FOXCROFT TO
MACHIAS. AREAS TO THE SOUTH OF THIS LINE ARE CLEAR WITH AREAS TO
THE NORTH CLOUDY. THE LINE WILL LIKELY CONTINUE TO SHIFT VERY
SLOWLY TO THE NORTH OVERNIGHT. AREAS FROM BAXTER STATE PARK ON
NORTH ARE EXPECTED TO REMAIN CLOUDY OVERNIGHT AND THE CEILINGS
WILL LIKELY CONTINUE THE TREND OF SLOWLY LOWERING. TEMPERATURES
IN THE STRATUS AREAS HAVE BEEN STEADY SINCE LATE AFTERNOON...AND
ARE NOT EXPECTED TO FALL MORE THAN A FEW DEGREES OVERNIGHT. ACROSS
THE SOUTH WHERE THE SKY IS CLEAR TEMPERATURES WILL CONTINUE TO
SLOWLY FALL. BY MORNING THE COLDEST SPOTS ARE LIKELY TO BE ACROSS
INTERIOR DOWNEAST. MADE SOME ADJUSTMENTS MAINLY TO THE SKY/TEMP
GRIDS BASED ON THE LATEST SATELLITE PICTS...OBSERVATIONS...AND
EXPECTED CONDITIONS OVERNIGHT.
627 PM UPDATE...THE FORECAST CHALLENGE FOR TONIGHT REMAINS THE
STRATUS THAT COVERS MUCH OF THE CWA. THE BACK EDGE OF THE STRATUS
HAS BEEN LIFTING NORTH...AND IS EXPECTED TO MOVE NORTH OF BANGOR
WITHIN THE HOUR. THE SOUTHERN EDGE IS EXPECTED TO SLOWLY ERODE
THIS EVENING. IN THE FAR NORTH MOST OF THE GUIDANCE POINTS TOWARD
THE CEILINGS GRADUALLY LOWERING TO MVFR LATE THIS EVENING AND
OVERNIGHT. WILL MAKE SOME TWEAKS TO THE SKY GRIDS BASED ON THE
LATEST TENDS ON THE 11U-3.9 SATELLITE CHANNEL AND
OBSERVATIONS...OTHERWISE NO SIGNIFICANT CHANGES TO THE ONGOING
FORECAST ARE PLANNED WITH THIS UPDATE.
PREVIOUS DISCUSSION... A LARGE AREA OF HIGH PRESSURE CENTERED
ACROSS THE MID ATLANTIC COAST WILL MAINTAIN DRY WEATHER ACROSS THE
AREA TONIGHT AND FRIDAY. SKIES WILL REMAIN MOSTLY CLEAR DOWNEAST.
MOISTURE STREAMING ALONG A FAST MOVING JET STREAM ACROSS THE NORTH
IN COMBINATION WITH A WEAK WEATHER DISTURBANCE MOVING THROUGH
QUEBEC WILL CONTINUE TO BRING STRATUS CLOUDS OVER NORTHERN AREAS
THROUGH FRIDAY. SOME LIGHT SPRINKLES OR FLURRIES ARE POSSIBLE OVER
THE HIGHER ELEVATIONS OF THE NORTH ON FRIDAY. OTHERWISE, DRY
WEATHER IS EXPECTED TO PERSIST THROUGH FRIDAY.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY/...
A WEAK SURFACE LOW WILL TRACK ACROSS CENTRAL QUEBEC FRIDAY EVNG
WITH ASSOCIATED SHORT WAVE WILL MOVE THROUGH OVRNGT FRI. THIS WILL
PRODUCE A SLIGHT CHANCE FOR SHOWERS ACROSS NRN MAINE SAT
MRNG...OTHERWISE HIGH PRESSURE WILL DOMINATE THE WEATHER THROUGH
THE SHORT TERM PERIOD OF THE FORECAST.
LOADED A BLEND OF NAM/GFS/ECMWF FOR SKY/POP/WNDS. MATCH GUIDE FOR
MAX/MIN. NAWAVE4 FOR SEAS. ADDED 15 PERCENT TO THE WINDS FOR GUSTS
OVER LAND 25 PERCENT OVER WATER.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE SYSTEM OVER THE AREA EARLY IN THE PERIOD WILL
RETREAT INTO THE NORTH ATLANTIC AS A LOW PRESSURE MOVING THROUGH
THE GREAT LAKES PUSHES INTO THE ERN LAKES. AT THE START OF THE
PERIOD A LOW CNTRD OVR NRN LAKE MICHIGAN...WITH AN ASSOCIATED
FRONT EXTENDING INTO NRN CANADA...AND TO THE GULF OF MEXICO. THE
GFS AND NAM ARE IN PRETTY GOOD AGREEMENT OVER THE POSITION OF THE
LOW AND ASSOCIATED FRONT...THE ECMWF HAS THE LOW FARTHER SOUTH OVR
SE WI. MON MRNG THE GFS MOVES THE LOW TO SE JAMES BAY...THE FRONT
TO WRN ME. THE ECMWF MOVES THE LOW TO NRN LAKE MI...THE FRONT TO
THE ERN GREAT LAKES. THROUGH THE PERIOD THE ECMWF TRAILS THE GFS
BY ABOUT 12HRS. THE GFS MOVES THE FRONT THROUGH BY MON EVNG...THE
ECMWF BY TUE MRNG. ONCE THROUGH HIGHER PRESSURE WILL DOMINATE
THROUGH THE PERIOD. LOADED SUPERBLEND FOR EXTENDED.
&&
.AVIATION /05Z FRIDAY THROUGH TUESDAY/...
NEAR TERM: VFR CEILINGS OF AROUND 3500 AGL AT THE NORTHERN TAF
SITES ARE EXPECTED TO GRADUALLY LOWER TO MVFR AROUND 06-07Z AT KFVE
AND 08/09Z AT KCAR AND KPQI. THE CEILINGS ARE EXPECTED TO LIFT TO
VFR BY LATE MORNING FRI. VFR EXPECTED AT KBHB AND KBGR THROUGH
FRI.
SHORT TERM: VFR CONDITIONS ALL SITES THROUGH THE PERIOD
EXCEPT...KFVE...KCAR...AND KPQI MVFR.
&&
.MARINE...
NEAR TERM: SEAS ARE RUNNING ABOUT 4 FT AT THE EASTERN MAINE SHELF
THIS EVENING WITH A WSW WIND OF AROUND 10 KNOTS. CONDITIONS ARE
EXPECTED TO REMAIN BELOW SCA TONIGHT AND FRIDAY.
SHORT TERM: WINDS AND SEAS BELOW SCA THROUGH THE PERIOD.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...RB
SHORT TERM...VJN
LONG TERM...VJN
AVIATION...RB/VJN
MARINE...RB/VJN
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1254 AM EST FRI NOV 15 2013
.SYNOPSIS...
HIGH PRESSURE WILL SLOWLY MOVE OFF THE EAST COAST THROUGH FRIDAY
AS A RAPIDLY MOVING WEATHER DISTURBANCE SLIDES EAST THROUGH
QUEBEC. HIGH PRESSURE WILL REBUILD ACROSS MAINE AND THE MARITIMES
THIS WEEKEND.&&
.NEAR TERM /THROUGH TODAY/...
1245 AM UPDATE...STRATUS DECK ACROSS NRN NEW ENGLAND CONTINUES TO
BE THE MAIN FORECAST CONCERN FOR THE NEAR TERM. THERE IS A PRETTY
STRONG GRADIENT FROM CLOUDY TO MOSTLY CLEAR FROM CALAIS WWD TO
DEXTER. BOTH THE NAM AND RAP INDICATE THAT THE BACK EDGE OF THIS
STRATUS SHOULD CONTINUE TO MOVE NORTH THIS MORNING. THE STRATUS
WILL BECOME MORE OF A STRATOCU DECK ACROSS OUR NRN ZONES TODAY...WITH
SOME BREAKS IN THE CLOUD COVER DEVELOPING. FURTHER SOUTH...SKIES
WILL BE PARTLY TO MOSTLY SUNNY. TEMPS IN THE CLEAR AREAS WILL
GENERALLY BE IN THE 20S EARLY THIS MORNING...WITH 30S IN THE
CLOUDY AREAS. TEMPS SHOULD WARM INTO THE 40S FOR HIGH TEMPS THIS
AFTERNOON...WITH LOWER 50S POSSIBLE ACROSS THE SRN THIRD OF THE
FCST AREA.
940 PM UPDATE...THE STRATUS DECK CONTINUES TO SHIFT SLOWLY NORTH
AND AS OF 0230Z EXTENDS ON A LINE FROM ABOUT DOVER-FOXCROFT TO
MACHIAS. AREAS TO THE SOUTH OF THIS LINE ARE CLEAR WITH AREAS TO
THE NORTH CLOUDY. THE LINE WILL LIKELY CONTINUE TO SHIFT VERY
SLOWLY TO THE NORTH OVERNIGHT. AREAS FROM BAXTER STATE PARK ON
NORTH ARE EXPECTED TO REMAIN CLOUDY OVERNIGHT AND THE CEILINGS
WILL LIKELY CONTINUE THE TREND OF SLOWLY LOWERING. TEMPERATURES
IN THE STRATUS AREAS HAVE BEEN STEADY SINCE LATE AFTERNOON...AND
ARE NOT EXPECTED TO FALL MORE THAN A FEW DEGREES OVERNIGHT. ACROSS
THE SOUTH WHERE THE SKY IS CLEAR TEMPERATURES WILL CONTINUE TO
SLOWLY FALL. BY MORNING THE COLDEST SPOTS ARE LIKELY TO BE ACROSS
INTERIOR DOWNEAST. MADE SOME ADJUSTMENTS MAINLY TO THE SKY/TEMP
GRIDS BASED ON THE LATEST SATELLITE PICTS...OBSERVATIONS...AND
EXPECTED CONDITIONS OVERNIGHT.
627 PM UPDATE...THE FORECAST CHALLENGE FOR TONIGHT REMAINS THE
STRATUS THAT COVERS MUCH OF THE CWA. THE BACK EDGE OF THE STRATUS
HAS BEEN LIFTING NORTH...AND IS EXPECTED TO MOVE NORTH OF BANGOR
WITHIN THE HOUR. THE SOUTHERN EDGE IS EXPECTED TO SLOWLY ERODE
THIS EVENING. IN THE FAR NORTH MOST OF THE GUIDANCE POINTS TOWARD
THE CEILINGS GRADUALLY LOWERING TO MVFR LATE THIS EVENING AND
OVERNIGHT. WILL MAKE SOME TWEAKS TO THE SKY GRIDS BASED ON THE
LATEST TENDS ON THE 11U-3.9 SATELLITE CHANNEL AND
OBSERVATIONS...OTHERWISE NO SIGNIFICANT CHANGES TO THE ONGOING
FORECAST ARE PLANNED WITH THIS UPDATE.
PREVIOUS DISCUSSION... A LARGE AREA OF HIGH PRESSURE CENTERED
ACROSS THE MID ATLANTIC COAST WILL MAINTAIN DRY WEATHER ACROSS THE
AREA TONIGHT AND FRIDAY. SKIES WILL REMAIN MOSTLY CLEAR DOWNEAST.
MOISTURE STREAMING ALONG A FAST MOVING JET STREAM ACROSS THE NORTH
IN COMBINATION WITH A WEAK WEATHER DISTURBANCE MOVING THROUGH
QUEBEC WILL CONTINUE TO BRING STRATUS CLOUDS OVER NORTHERN AREAS
THROUGH FRIDAY. SOME LIGHT SPRINKLES OR FLURRIES ARE POSSIBLE OVER
THE HIGHER ELEVATIONS OF THE NORTH ON FRIDAY. OTHERWISE, DRY
WEATHER IS EXPECTED TO PERSIST THROUGH FRIDAY.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY/...
A WEAK SURFACE LOW WILL TRACK ACROSS CENTRAL QUEBEC FRIDAY EVNG
WITH ASSOCIATED SHORT WAVE WILL MOVE THROUGH OVRNGT FRI. THIS WILL
PRODUCE A SLIGHT CHANCE FOR SHOWERS ACROSS NRN MAINE SAT
MRNG...OTHERWISE HIGH PRESSURE WILL DOMINATE THE WEATHER THROUGH
THE SHORT TERM PERIOD OF THE FORECAST.
LOADED A BLEND OF NAM/GFS/ECMWF FOR SKY/POP/WNDS. MATCH GUIDE FOR
MAX/MIN. NAWAVE4 FOR SEAS. ADDED 15 PERCENT TO THE WINDS FOR GUSTS
OVER LAND 25 PERCENT OVER WATER.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE SYSTEM OVER THE AREA EARLY IN THE PERIOD WILL
RETREAT INTO THE NORTH ATLANTIC AS A LOW PRESSURE MOVING THROUGH
THE GREAT LAKES PUSHES INTO THE ERN LAKES. AT THE START OF THE
PERIOD A LOW CNTRD OVR NRN LAKE MICHIGAN...WITH AN ASSOCIATED
FRONT EXTENDING INTO NRN CANADA...AND TO THE GULF OF MEXICO. THE
GFS AND NAM ARE IN PRETTY GOOD AGREEMENT OVER THE POSITION OF THE
LOW AND ASSOCIATED FRONT...THE ECMWF HAS THE LOW FARTHER SOUTH OVR
SE WI. MON MRNG THE GFS MOVES THE LOW TO SE JAMES BAY...THE FRONT
TO WRN ME. THE ECMWF MOVES THE LOW TO NRN LAKE MI...THE FRONT TO
THE ERN GREAT LAKES. THROUGH THE PERIOD THE ECMWF TRAILS THE GFS
BY ABOUT 12HRS. THE GFS MOVES THE FRONT THROUGH BY MON EVNG...THE
ECMWF BY TUE MRNG. ONCE THROUGH HIGHER PRESSURE WILL DOMINATE
THROUGH THE PERIOD. LOADED SUPERBLEND FOR EXTENDED.
&&
.AVIATION /05Z FRIDAY THROUGH TUESDAY/...
NEAR TERM: VFR CEILINGS OF AROUND 3500 AGL AT THE NORTHERN TAF
SITES ARE EXPECTED TO GRADUALLY LOWER TO MVFR AROUND 04Z AT KFVE
AND 07/08Z AT KCAR AND KPQI. THE CEILINGS ARE EXPECTED TO LIFT TO
VFR BY LATE MORNING FRI. VFR EXPECTED AT KBHB AND KBGR THROUGH
FRI.
SHORT TERM: VFR CONDITIONS ALL SITES THROUGH THE PERIOD
EXCEPT...KFVE...KCAR...AND KPQI MVFR.
&&
.MARINE...
NEAR TERM: SEAS ARE RUNNING ABOUT 4 FT AT THE EASTERN MAINE SHELF
THIS EVENING WITH A WSW WIND OF AROUND 10 KNOTS. CONDITIONS ARE
EXPECTED TO REMAIN BELOW SCA TONIGHT AND FRIDAY.
SHORT TERM: WINDS AND SEAS BELOW SCA THROUGH THE PERIOD.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...RB
SHORT TERM...VJN
LONG TERM...VJN
AVIATION...RB/VJN
MARINE...RB/VJN
AREA FORECAST DISCUSSION
NWS DULUTH MN
740 PM CST SAT NOV 16 2013
.UPDATE...
ISSUED AT 739 PM CST SAT NOV 16 2013
WE UPDATED GRIDS TO REFLECT LATEST RADAR TRENDS...WHICH WAS FOR
DIMINISHING RAIN ACROSS THE SOUTHERN CWA. OTHERWISE...GRIDS IN
GOOD SHAPE WITH ONLY MINOR CHANGES MADE.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 330 PM CST SAT NOV 16 2013
AT 330 PM...RAIN EXTENDED FROM THE BRAINERD LAKES REGION...THROUGH
THE TWIN PORTS AND EAST CENTRAL MN...AND NW WI. TEMPERATURES WERE
IN THE LOWER TO MIDDLE 40S FOR THE MOST PART WITH EAST TO
SOUTHEAST WINDS. THERE WERE MULTIPLE LIGHTNING STRIKES SHOWING UP
SOUTH OF THE CWA EARLIER THIS AFTERNOON...BUT THEY HAD LARGELY
SHIFTED TO NE WI AND SW WI.
THE NAM SEEMS TO HAVE A GOOD HANDLE ON CURRENT TRENDS...AS DOES
THE 4KM NMM WRF. AS THE SURFACE LOW AND UPPER LEVEL SHORTWAVE
MOVES NE...IT WILL GRADUALLY PUSH THE MAJORITY OF THE
PRECIPITATION INTO THE ARROWHEAD AND NW WI DURING THE EVENING. THE
FOCUS WILL THEN SHIFT TO NW/NC MN AFTER MIDNIGHT...WITH A DRY SLOT
WORKING ITS WAY INTO NW WI. WILL HIT POPS HARDEST IN THE SOUTH
THIS EVENING...AND THE NORTH OVERNIGHT. FORECAST SOUNDINGS
INDICATE THE PRECIPITATION WILL LARGELY BE IN THE FORM OF RAIN.
THE SYSTEM MOVING THROUGH THE REGION IS FAIRLY COMPLEX...WITH THE
FOCUS FOR PRECIPITATION ACROSS NORTHERN AREAS SHIFTING TO CANADA
DURING THE AFTERNOON. MEANWHILE...RAIN WILL OVERTAKE EC MN/NW WI
AGAIN DURING THE DAY SUNDAY. COULD BE A MIX IN PORTIONS OF
NORTHERN MN. NOT CONVINCED THERE WILL BE MUCH IN THE WAY OF
ACCUMULATION...BUT COULD BE UP TO AN INCH IN SPOTS BEFORE THE
PRECIPITATION DIMINISHES SOUTH TO NORTH.
COLDER AIR WILL CONTINUE TO INFILTRATE THE REGION FROM THE NW ON
SUNDAY...ALTHOUGH THE MAIN COOLING SHOULD TAKE PLACE LATER IN THE
DAY OR BY SUNDAY NIGHT. GUSTY NORTHWEST WINDS WILL DEVELOP ON
SUNDAY...DUE TO STRENGTHENING CAA AND A STRENGTHENING GRADIENT
WITH A DISTINCT ISALLOBARIC COMPONENT TO THE WINDS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 330 PM CST SAT NOV 16 2013
SUNDAY NIGHT THROUGH FRIDAY...
STRONG LOW PRESSURE SYSTEM OVER THE GREAT LAKES LIFTING N/NEWD WILL
CONTINUE TO WRAP AROUND LIGHT SNOW SHOWERS OR FLURRIES THROUGH MUCH
OF THE NORTHLAND SUN NIGHT AND EARLY MONDAY. THE AIR MASS WILL BE
COLD ENOUGH FOR POTENTIAL LAKE EFFECT/ENHANCED SNOW ALONG THE SOUTH
SHORE DURING THIS TIME. HOWEVER...DRIER AIR WILL BE QUICKLY MOVING
IN AND WINDS WILL HAVE TOO MUCH OF A WLY COMPONENT TO PROMOTE
SIGNIFICANT LES. COULD SEE A COUPLE INCHES IN ASHLAND AND IRON
COUNTIES. OTHERWISE...MOST AREAS WILL RECEIVE AN INCH OR LESS. THE
OTHER FACTOR WITH THIS SYSTEM EJECTING OUT WILL BE THE STRONG NW
WINDS. HIGH PRESSURE BUILDING IN QUICKLY OVER THE NRN PLAINS WILL
COMBINE WITH THE DEEPENING SYSTEM TO THE EAST TO PRODUCE A VERY
TIGHT PRESSURE GRADIENT. WILL LIKELY SEE SUSTAINED WINDS SUN NIGHT
AROUND 20 MPH...AND GUSTS TO 30 MPH. THE COLD TEMPS COMBINED WITH
STRONG WINDS WILL PRODUCE WIND CHILLS IN THE TEENS.
A BROAD UPPER RIDGE AND SFC HIGH BUILD IN LATE MON AND EARLY TUESDAY
WHICH WILL ALLOW FOR DRY CONDITIONS AND GRADUAL WARMING
TEMPERATURES. HOWEVER...THE NEXT COLD ARCTIC SYSTEM WILL BEGIN TO
DIG INTO THE NRN ROCKIES BY MID WEEK AND LIFT QUICKLY THROUGH THE
UPPER MIDWEST WED NIGHT AND THURSDAY. THE SYSTEM WILL BE COLD
ENOUGH FOR LIGHT SNOW. A RE-ENFORCING S/W WILL MOVE ACROSS THE
CENTRAL CONUS BY FRIDAY AND BRING ADDITIONAL CHANCES FOR LIGHT SNOW.
A CHILLY START TO THE EXTENDED WITH HIGHS ON MONDAY IN THE UPPER 20S
AND LOWER 30S AND MORNING LOWS IN THE LOWER TO MID 20S...WILL
QUICKLY TURN WARMER TUE AND WED WITH HIGHS IN THE UPPER 30S AND
LOWER 40S. ANOTHER BLAST OF COLD AIR WILL DROP HIGH TEMPS
BACK INTO THE 20S AND 30S...AND OVERNIGHT LOWS IN THE TEENS AND
LOWER 20S BY THE END OF THE WORK WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 540 PM CST SAT NOV 16 2013
IFR CONDITIONS WILL PREVAIL THROUGH THE NIGHT ACROSS MOST
AREAS...WITH AREAS OF FOG...LIGHT RAIN OR DRIZZLE. SATELLITE
IMAGERY AND OBSERVATIONS WAS SHOWING THE LOW CLOUDS DIMINISHING
OVER FAR SOUTHWEST MINNESOTA AS OF 2315Z...AND THE RAP WAS PICKING
UP ON THIS AS WELL. THIS CLEARING MAY WORK INTO NORTHERN WISCONSIN
LATE TONIGHT...AND WE DID INCLUDE SOME TEMPORARY CLEARING AT KHYR.
WINDS WILL SWITCH TO THE WEST TO NORTHWEST LATE TONIGHT INTO
SUNDAY MORNING AND THAT SHOULD IMPROVE VSBYS AND CAUSE CEILINGS TO
RISE SOME TO EITHER HIGHER END IFR OR MVFR. THE NORTHWEST WINDS
WILL BRING IN COLDER AIR...WITH SOME SNOW POSSIBLE OVER PARTS OF
NORTHERN MINNESOTA.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 40 44 26 31 / 80 40 30 10
INL 36 38 22 28 / 80 70 40 10
BRD 39 43 23 32 / 40 30 10 0
HYR 42 47 26 34 / 80 60 40 10
ASX 41 47 29 35 / 90 60 60 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
UPDATE...MELDE
SHORT TERM...DAP
LONG TERM...BJT
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
710 PM CST SAT NOV 16 2013
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 240 PM CST SAT NOV 16 2013
FIRST WAVE OF -RA/-DZ...AND EVEN A FEW THUNDERSTORMS THAT DEVELOPED
ALONG THE LEADING EDGE OF THE STRONG VERTICAL LIFT ACROSS EC/SC MN
EARLIER THIS AFTN. VISIBLE SATELLITE IMAGERY THIS AFTN INDICATED THE
DRIER AIR MOVING ACROSS NW IOWA WHICH WILL IMPACT FAR SOUTHERN MN
THIS EVENING. SOME BREAKS IN THE CLD CVR ARE LIKELY WITH THIS AREA
OF DRIER AIR...BUT HOW FAR NORTH THIS CLEARING DEVELOPS REMAINS
UNCERTAIN. LATEST RAP HAS AREAS SOUTH OF HWY 212 REMAINING NEARLY
SATURATED BLW 2K THRU TONIGHT.
DEEP SFC LOW IN NE SD WILL SLOWLY MOVE ENE ACROSS CENTRAL MN THIS
EVENING...AND THEN ACROSS NE MN BY SUNDAY MORNING. THIS WILL KEEP
MOST OF CENTRAL MN IN A WEAK FLOW IN THE BOUNDARY LAYER AND
THEREFORE KEEPING LOW CLDS/FOG AND OCCASIONAL DRIZZLE IN THE
FORECAST. NEXT SHRTWV OF INTEREST WILL IMPACT MAINLY THE SE CWA
WITH -RA SUNDAY MORNING...INTO THE EARLY AFTN. FURTHER TO THE
NW...THERE REMAINS ENOUGH ENERGY TO KEEP LOW POPS OVERNIGHT...BUT
WITH CAA ANY PRECIPITATION AMTS WILL REMAIN LIGHT. SOME
-SN/FLURRIES ARE POSSIBLE SUNDAY AFTN BEFORE ANY LEFTOVER
PRECIPITATION ENDS ACROSS CENTRAL MN...BUT NOT CONFIDENT ENOUGH TO
INCLUDE IN THIS FORECAST PACKAGE. TEMPS MAY BE A BIT LOWER IN FAR
SOUTHERN MN IF SKIES CLR. THE LOW CLDS/FOG AND DRIZZLE WILL KEEP
THE REST OF THE CWA WITH LITTLE TEMP CHG UNTIL SUNDAY AS WINDS
SHIFT TO THE W/NW AND BEGIN TO GUST.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 240 PM CST SAT NOV 16 2013
DRIER AIR SHOULD FOLLOW THE FROPA QUICKLY SUNDAY NIGHT WITH
CLEARING SKIES INTO MONDAY. MODELS CONTINUE TO ADVERTISE A
SIDESWIPING OF THE TROUGH MONDAY BEFORE IMPRESSIVE RIDGING
RETURNS TUESDAY AND WEDNESDAY. INCREASED TEMPS A DEGREE OR TWO
MONDAY AND MONDAY NIGHT...BUT SEVERAL DEGREES TUESDAY AS 925 MB
TEMPS OF +4C TO +8C PUSH INTO THE CWA. MIXING TO THAT LEVEL WOULD
YIELD HIGHS IN THE MID/UPPER 50S OVER SOUTHERN MN AND UPPER 40S
OVER WRN WI. DID NOT QUITE GO THAT HIGH YET SINCE THIS IS A
RELATIVELY NEW MODEL TREND...BUT EACH OF THE LAST SEVERAL RUNS
HAVE BEEN GETTING PROGRESSIVELY WARMER.
MODEL CONSISTENCY HAS IMPROVED TODAY WITH A DRY COLD FRONT
PROGGED TO PUSH THROUGH LATE WEDNESDAY OR WEDNESDAY NIGHT. THERMAL
RIDGING IN ADVANCE OF THE FRONT WILL KEEP TEMPERATURES MILD
TUESDAY NIGHT AND WEDNESDAY. A 1040 MB HIGH WILL BUILD IN BEHIND
THE FRONT...BUT MODELS DIFFER A BIT WHERE THIS WILL TRACK WHICH
WILL DETERMINE THE DEGREE OF COLD AIR LATE NEXT WEEK.
AN INVERTED TROUGH PUSHING THROUGH THURSDAY NIGHT OR FRIDAY MAY
BRING A COATING OF SNOW TO THE REGION. INTRODUCED LOW POPS FOR NOW
DURING THIS PERIOD.
AN INTERESTING DEVELOPMENT HAS EMERGED ON THE 12Z ECMWF AND
CANADIAN FOR NEXT WEEKEND. FOLLOWING THE INVERTED TROUGH...A
PROLIFIC 1050-1055MB HIGH BUILDING INTO THE NORTHERN
ROCKIES/NORTHWESTERN PLAINS COULD BRING OUR FIRST SHOT AT VERY
COLD TEMPERATURES. HOWEVER...THE GFS AND FIM MAINTAIN A MUCH
MILDER SOLUTION WITH A WEAKER AND MORE PROGRESSIVE HIGH REMAINING
IN CANADA SO CANNOT TREND TOWARD EITHER SOLUTION YET.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 629 PM CST SAT NOV 16 2013
VERY TRICKY SET OF TAFS THIS EVENING AS ONE AREA OF LOW PRES OVER
ERN SD/SW MN SLOWLY SHIFTS NE INTO NE MN BY DAYBREAK...WITH A
SECOND TRAILING LOW PRES CENTER OVER ERN KS EXPECTED TO SHIFT ENE
INTO SRN WI BY MIDDAY SUN. THE FIRST AREA OF RAIN HAS JUST ABOUT
SHIFTED NE OUT OF RANGE OF THE WFO MPX TAF SITES...BUT THIS IS
BEING FOLLOWED BY A DRY SLOT THAT IS HAVING A NUMBER OF IMPACTS
OVER THE SITES - NAMELY RISING CEILINGS...DROPPING VSBY...AND
MESOSCALE WIND SHIFTS THAT ARE DIFFICULT TO TAME UNTIL THE FIRST
LOW PRES CENTER SHIFTS OFF TO THE NE. NOT THE GREATEST CONFIDENCE
IN THE SHORT-TERM DETAILS DUE TO SUCH HIGH VARIATION...BUT THE
OVERARCHING THINKING IS THAT THE DRY SLOT WILL MAINLY IMPACT KRWF-
KMSP-KRNH-KEAU BEFORE IT PUSHES AWAY TO THE NE AND FILLS BACK IN.
THEN ALL SITES ARE EXPECTED TO DEAL WITH LOW CEILINGS AND REDUCED
VSBYS...ESSENTIALLY IFR-OR-LESS MAINLY AFTER MIDNIGHT AND LASTING
THRU DAYBREAK. AS THE SECONDARY LOW PRES CENTER APPROACHES...
ANOTHER SWATH OF -RA IS EXPECTED TO DEVELOP FROM THE S AND SHIFT
NE...MAINLY IMPACTING KMSP EASTWARD. HOWEVER...BEHIND THIS SECOND
LOW PRES CENTER...CONDS ARE EXPECTED TO STEADILY IMPROVE TMRW AFTN
TO VFR CONDS. IN TANDEM WITH THE IMPROVEMENT WILL BE A SIGNIFICANT
SWING IN WINDS FROM SW TO NW ALONG WITH A STRONG INCRS IN SPEEDS
TO ARND 20G30KT.
KMSP...INITIALIZED WITH DRY SLOT CLEARING AREA BEING REFLECTED IN
THE MSP OBS...SO IT/S A MATTER OF HOW LONG IT LASTS. MODEL
SOUNDINGS SHOW THE LOWER LEVELS FILLING BACK IN...IN ADVANCE OF
THE SECONDARY LOW PRES CENTER OVER KS...ARND MIDNIGHT SO HAVE
BROUGHT BACK LOWER-END MVFR CEILINGS FOR MUCH OF THE OVERNIGHT
PERIOD. HAVE ALSO MAINTAINED MVFR VSBY AS THERE WILL BE AREAS OF
FOG/-DZ OVERNIGHT BUT WITH WINDS REMAINING UP...AM NOT EXPECTING
VSBY TO DROP INTO IFR-OR-LOWER RANGE FOR MUCH TIME AT ALL. AFTER
DAYBREAK...-RA LOOKS TO RETURN FOR A BRIEF PERIOD IN THE MORNING
AS THAT SECONDARY LOW PRES CENTER SHIFTS OVER THE E OF THE AREA.
CONDS THEN IMPROVE GOING INTO TMRW AFTN AND EVE...BUT WINDS BECOME
A SIGNIFICANT ISSUE AS THEY SWING FROM SW TO NW TMRW MRNG THEN
STRONGLY INCRS IN SPEED TMRW AFTN AND EVE. OVERALL...WILL NEED TO
KEEP CLOSE TABS ON THINGS AS AMENDMENTS MAY BE FAIRLY FREQUENT.
/OUTLOOK FOR KMSP/
MON...MVFR CIGS EARLY. THEN VFR. WINDS WNW AT 10G15KTS.
TUE...VFR. WINDS SE AT 10KTS.
WED...VFR WITH MVFR AND -RA LATE. WINDS SSW AT 10G15KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JLT
LONG TERM...BORGHOFF
AVIATION...JPC
AREA FORECAST DISCUSSION
NWS DULUTH MN
541 PM CST SAT NOV 16 2013
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 330 PM CST SAT NOV 16 2013
AT 330 PM...RAIN EXTENDED FROM THE BRAINERD LAKES REGION...THROUGH
THE TWIN PORTS AND EAST CENTRAL MN...AND NW WI. TEMPERATURES WERE
IN THE LOWER TO MIDDLE 40S FOR THE MOST PART WITH EAST TO
SOUTHEAST WINDS. THERE WERE MULTIPLE LIGHTNING STRIKES SHOWING UP
SOUTH OF THE CWA EARLIER THIS AFTERNOON...BUT THEY HAD LARGELY
SHIFTED TO NE WI AND SW WI.
THE NAM SEEMS TO HAVE A GOOD HANDLE ON CURRENT TRENDS...AS DOES
THE 4KM NMM WRF. AS THE SURFACE LOW AND UPPER LEVEL SHORTWAVE
MOVES NE...IT WILL GRADUALLY PUSH THE MAJORITY OF THE
PRECIPITATION INTO THE ARROWHEAD AND NW WI DURING THE EVENING. THE
FOCUS WILL THEN SHIFT TO NW/NC MN AFTER MIDNIGHT...WITH A DRY SLOT
WORKING ITS WAY INTO NW WI. WILL HIT POPS HARDEST IN THE SOUTH
THIS EVENING...AND THE NORTH OVERNIGHT. FORECAST SOUNDINGS
INDICATE THE PRECIPITATION WILL LARGELY BE IN THE FORM OF RAIN.
THE SYSTEM MOVING THROUGH THE REGION IS FAIRLY COMPLEX...WITH THE
FOCUS FOR PRECIPITATION ACROSS NORTHERN AREAS SHIFTING TO CANADA
DURING THE AFTERNOON. MEANWHILE...RAIN WILL OVERTAKE EC MN/NW WI
AGAIN DURING THE DAY SUNDAY. COULD BE A MIX IN PORTIONS OF
NORTHERN MN. NOT CONVINCED THERE WILL BE MUCH IN THE WAY OF
ACCUMULATION...BUT COULD BE UP TO AN INCH IN SPOTS BEFORE THE
PRECIPITATION DIMINISHES SOUTH TO NORTH.
COLDER AIR WILL CONTINUE TO INFILTRATE THE REGION FROM THE NW ON
SUNDAY...ALTHOUGH THE MAIN COOLING SHOULD TAKE PLACE LATER IN THE
DAY OR BY SUNDAY NIGHT. GUSTY NORTHWEST WINDS WILL DEVELOP ON
SUNDAY...DUE TO STRENGTHENING CAA AND A STRENGTHENING GRADIENT
WITH A DISTINCT ISALLOBARIC COMPONENT TO THE WINDS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 330 PM CST SAT NOV 16 2013
SUNDAY NIGHT THROUGH FRIDAY...
STRONG LOW PRESSURE SYSTEM OVER THE GREAT LAKES LIFTING N/NEWD WILL
CONTINUE TO WRAP AROUND LIGHT SNOW SHOWERS OR FLURRIES THROUGH MUCH
OF THE NORTHLAND SUN NIGHT AND EARLY MONDAY. THE AIR MASS WILL BE
COLD ENOUGH FOR POTENTIAL LAKE EFFECT/ENHANCED SNOW ALONG THE SOUTH
SHORE DURING THIS TIME. HOWEVER...DRIER AIR WILL BE QUICKLY MOVING
IN AND WINDS WILL HAVE TOO MUCH OF A WLY COMPONENT TO PROMOTE
SIGNIFICANT LES. COULD SEE A COUPLE INCHES IN ASHLAND AND IRON
COUNTIES. OTHERWISE...MOST AREAS WILL RECEIVE AN INCH OR LESS. THE
OTHER FACTOR WITH THIS SYSTEM EJECTING OUT WILL BE THE STRONG NW
WINDS. HIGH PRESSURE BUILDING IN QUICKLY OVER THE NRN PLAINS WILL
COMBINE WITH THE DEEPENING SYSTEM TO THE EAST TO PRODUCE A VERY
TIGHT PRESSURE GRADIENT. WILL LIKELY SEE SUSTAINED WINDS SUN NIGHT
AROUND 20 MPH...AND GUSTS TO 30 MPH. THE COLD TEMPS COMBINED WITH
STRONG WINDS WILL PRODUCE WIND CHILLS IN THE TEENS.
A BROAD UPPER RIDGE AND SFC HIGH BUILD IN LATE MON AND EARLY TUESDAY
WHICH WILL ALLOW FOR DRY CONDITIONS AND GRADUAL WARMING
TEMPERATURES. HOWEVER...THE NEXT COLD ARCTIC SYSTEM WILL BEGIN TO
DIG INTO THE NRN ROCKIES BY MID WEEK AND LIFT QUICKLY THROUGH THE
UPPER MIDWEST WED NIGHT AND THURSDAY. THE SYSTEM WILL BE COLD
ENOUGH FOR LIGHT SNOW. A RE-ENFORCING S/W WILL MOVE ACROSS THE
CENTRAL CONUS BY FRIDAY AND BRING ADDITIONAL CHANCES FOR LIGHT SNOW.
A CHILLY START TO THE EXTENDED WITH HIGHS ON MONDAY IN THE UPPER 20S
AND LOWER 30S AND MORNING LOWS IN THE LOWER TO MID 20S...WILL
QUICKLY TURN WARMER TUE AND WED WITH HIGHS IN THE UPPER 30S AND
LOWER 40S. ANOTHER BLAST OF COLD AIR WILL DROP HIGH TEMPS
BACK INTO THE 20S AND 30S...AND OVERNIGHT LOWS IN THE TEENS AND
LOWER 20S BY THE END OF THE WORK WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 540 PM CST SAT NOV 16 2013
IFR CONDITIONS WILL PREVAIL THROUGH THE NIGHT ACROSS MOST
AREAS...WITH AREAS OF FOG...LIGHT RAIN OR DRIZZLE. SATELLITE
IMAGERY AND OBSERVATIONS WAS SHOWING THE LOW CLOUDS DIMINISHING
OVER FAR SOUTHWEST MINNESOTA AS OF 2315Z...AND THE RAP WAS PICKING
UP ON THIS AS WELL. THIS CLEARING MAY WORK INTO NORTHERN WISCONSIN
LATE TONIGHT...AND WE DID INCLUDE SOME TEMPORARY CLEARING AT KHYR.
WINDS WILL SWITCH TO THE WEST TO NORTHWEST LATE TONIGHT INTO
SUNDAY MORNING AND THAT SHOULD IMPROVE VSBYS AND CAUSE CEILINGS TO
RISE SOME TO EITHER HIGHER END IFR OR MVFR. THE NORTHWEST WINDS
WILL BRING IN COLDER AIR...WITH SOME SNOW POSSIBLE OVER PARTS OF
NORTHERN MINNESOTA.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 40 44 26 31 / 70 40 30 10
INL 36 38 22 28 / 70 70 40 10
BRD 39 43 23 32 / 60 30 10 0
HYR 42 47 26 34 / 80 60 40 10
ASX 43 47 29 35 / 80 60 60 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...DAP
LONG TERM...BJT
AVIATION...MELDE
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1136 PM CST Thu Nov 14 2013
.UPDATE:
Issued at 910 PM CST Thu Nov 14 2013
The warming trend will continue with warmer lows tgt than
Wednesday ngt due to continued sly sfc winds and swly low
level/boundry layer winds, mid-high level cloudiness, and slightly
higher sfc dew points compared to the previous ngt. There was a
few weak radar echoes moving into swrn MO this evng associated
with weak low-mid level waa ahead of a shortwave moving ewd
through the srn Plains. Could not rule out sprinkles from mid
level clouds towards mrng in portions of cntrl and sern MO,
although the lower level below 700 mb should remain quite dry
through 12z Friday.
GKS
&&
.SHORT TERM: (Through Late Tonight)
Issued at 348 PM CST Thu Nov 14 2013
A dry air mass with low dew points will promote efficient cooling
tonight, however WAA and mid/high clouds will temper the drop-off and
keep overnight lows in the mid 30s.
Kanofsky
.LONG TERM: (Friday through Next Thursday)
Issued at 348 PM CST Thu Nov 14 2013
A weak disturbance was located over central NM around 21z per water
vapor imagery and recent RAP 1.5 PVU analyses. This feature will
quickly swing through TX tonight before reaching AR and MS tomorrow.
Although the air mass over MO/IL remains fairly dry, a few sprinkles
or light rain showers are possible over the eastern Ozarks on Fri
morning before this vort max lifts away from the area.
Look for a continued warming trend through the weekend due to
persistent southwest surface flow along with warming temperatures
aloft. Highs will probably reach the mid to upper 70s on Sun despite
substantial cloud cover and periods of precipitation. High
temperatures will fall back into the 30s and 40s early next week
after a strong cold front moves across the region on Sunday
afternoon and evening.
Wind speeds will increase on Fri night as the pressure gradient
tightens between the surface high over the southeast US and the
developing low pressure system over the plains. Expect breezy
conditions through Sun with the highest wind speeds and gusts on
Sat.
Two low pressure systems are expected to affect our area this
weekend. The first vort max was located near the WA coast around 18z
this afternoon and is forecast to reach KS by Sat. The LLJ induced
by this feature will interact with a lifting warm front to produce
an area of rain on late Fri night and Sat morning. PW values are
forecast to rise to around 1.2" by Sat, which is around +2 SD for
November, so plenty of moisture will be available. There will
probably be a break in the rain sometime on Sat aftn between
systems. A stronger vort max is forecast to cross the Rockies and
induce surface cyclogenesis along the pre-existing baroclinic zone
over OK/KS on Sat night. Instability and lift ahead of this system
should support an area of rain showers with embedded thunderstorms.
The attendant cold front then moves through the CWA on Sun aftn/eve
as the system lifts towards the Great Lakes and begins to occlude.
With substantial shear in place along with at least some
instability, there is a potential for severe thunderstorms on Sun
ahead of the advancing cold front. Although there are some timing
differences between models, most of the latest model runs bring the
cold front through the LSX CWA before 00z Mon. Such timing would
limit the severe weather threat across our area to the far eastern
CWA at most. If future model runs support a slower fropa, then there
may be more of a concern for severe thunderstorms.
Kanofsky
&&
.AVIATION: (For the 06z TAFs through 06z Friday Night)
Issued at 1106 PM CST Thu Nov 14 2013
VFR conditions are expected to continue through the forecast
period with southerly winds. An area of light rain over southern
Missouri tonight continues to make slow northeastward progression,
though sprinkles cannot be ruled out at KCOU during the late
overnight/early morning hours, confidence is too low to include in
the TAF at this time. All other TAF sites are expected to remain
dry, with the greatest chance for precipitation overnight tonight
mainly over southeastern Missouri, well south of TAF locations.
Otherwise, look for mid-level clouds to continue to filter over the
area, with low VFR cigs possible by the end of the forecast
period. The only other concern is LLWS tonight, which similar to
last night, remains marginal, precluding mention in the TAF
package.
Specifics for KSTL:
Dry conditions are expected to prevail this forecast period, with
mid-level clouds continuing to stream over the area from the
southwest. VFR conditions should persist through 06Z Saturday,
though expect MVFR by the end of the forecast period ahead of the
approaching weather system. Winds will remain southerly to
southwesterly tonight and Friday, backing to the southeast by
Friday night. Once again (and similar to last night), LLWS mainly
from now through 10-11Z remains marginal, and thus have elected
not to mention in the current TAF package.
JP
&&
.CLIMATE:
Issued at 348 PM CST Thu Nov 14 2013
Record highs for Sunday, November 17th
STL 78 1958
COU 78 1958
UIN 78 1952
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS GLASGOW MT
854 PM MST SAT NOV 16 2013
.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH MONDAY...
UPDATE...
ADJUSTED POPS TO BETTER REFLECT CURRENT RADAR OBSERVATIONS AND
RECENT TRENDS. TWEAKS TO TEMPERATURES AND SKY COVER WERE ALSO
IMPLEMENTED. POPULATED THE WIND GRIDS USING THE LATEST HIGH
RESOLUTION MODEL DATA. THE MAIN CHALLENGE OVERNIGHT AND INTO
SUNDAY MORNING WILL BE IDENTIFYING WHERE STEADIER BANDS OF
PRECIPITATION OCCUR. TIMING/LOCATION OF THESE BANDS WILL BE
DIFFICULT TO GET DOWN...BUT CRITICAL AS THESE LOCATIONS WILL
LIKELY SEE HIGHEST SNOWFALL TOTALS. MALIAWCO
PREVIOUS SHORT TERM DISCUSSION...
SHORT TERM MODEL SOLUTIONS CONTINUE TO BE OF VERY LITTLE HELP AND
SIGNIFICANT SNOW FALL AMOUNT AND PLACEMENT DISCREPANCIES ABOUND.
FORECAST CHALLENGES WILL FOCUS ON TRYING TO WORK OUT THESE TWO
PROBLEMS THROUGH SUNDAY.
OF MOST HELP WILL LIKELY BE COMPARING RADAR IMAGERY WITH MODEL
SOLUTIONS TO SEE WHICH ONE IS PERFORMING THE BEST AND TRY TO LEAN
WITH OR TRUST THAT ONE MORE THAN THE OTHERS. AT THE ONSET OF THIS
SYSTEM...THE HRRR MODEL SEEMS TO BE PERFORMING THE BEST.
ENOUGH ACCUMULATING SNOW SEEMS LIKELY TO SNEAK ACROSS THE
INTERNATIONAL BORDER TO ACCUMULATE AROUND 2 INCHES FOR OUR
NORTHEASTERN ZONES. WENT AHEAD AND ISSUED A WINTER WEATHER
ADVISORY FOR SHERIDAN AND EASTERN ROOSEVELT COUNTIES. MOST OTHER
LOCATIONS WILL PROBABLY RECEIVE AROUND 1 INCH OF SNOW.
ALTHOUGH SOME MODELS SHOWED POST-FRONTAL WINDS BELOW 15
KNOTS...ALL NEAR SHORT-TERM AND HIGH-RESOLUTION MODELS ARE IN
AGREEMENT SHOWING STRONG AND GUSTY WEST-NORTHWESTERLY WINDS
PUSHING INTO THE AREA AFTER MIDNIGHT TONIGHT. CHOSE TO ISSUE A
LAKE WIND ADVISORY FROM AFTER MIDNIGHT TONIGHT THROUGH THE DAY ON
SUNDAY.
BY SUNDAY NIGHT...THE LARGE UPPER-LEVEL TROUGH PIVOTS
EASTWARD...PARTIALLY CLEARING OUR SKIES AND DRIVING ANY
PRECIPITATION AWAY AS THE FLOW ALOFT TURNS MORE ZONAL.
AFTER A GOOD HARD FREEZE TONIGHT AND SUNDAY NIGHT...TEMPERATURES
WILL EASILY REBOUND TO MORE NORMAL VALUES FOR THIS TIME OF YEAR.
BMICKELSON
.LONG TERM...MONDAY NIGHT THROUGH SATURDAY...
GOING FORECAST IS IN OVERALL GOOD SHAPE. MODELS CONTINUE TO AGREE
IN A SHORTWAVE PASSAGE LATE TUESDAY INTO WEDNESDAY. MODELS REMAIN
RELATIVELY DRY WITH THIS FEATURE...BUT WE CONSERVATIVELY TRENDED
UP POPS GIVEN DECENT CONSISTENCY.
MODEL DIFFERENCES ARE PRESENT FOR NEXT FRIDAY INTO SATURDAY. THE
GFS AND DGEX ARE WARMER...BUILDING IN WEAK RIDGING BEHIND THE
EXITING UPPER TROUGH. THE ECMWF AND GEM BOTH DROP ANOTHER UPPER
TROUGH THROUGH WITH ANOTHER BLAST OF ARCTIC AIR. CONTINUED TO
LEAN MORE ON THE SIDE OF THE COOLER ECMWF AND GEM DUE TO THEIR
RECENT BETTER PERFORMANCE...BUT REMAIN MUCH WARMER THEN THE
OPERATIONAL RUNS. GILCHRIST
PREVIOUS LONG TERM DISCUSSION...TUESDAY WILL BE MILD AND DRY WITH
ZONAL FLOW ALOFT. SHORTWAVE UPPER TROUGH MOVES THROUGH MONTANA ON
WEDNESDAY AND DRAGS A STRONG COLD FRONT SOUTH. THE SYSTEM HAS
LIMITED MOISTURE SO THAT THE ANY PRECIPITATION THAT OCCURS WILL BE
MAINLY ALONG THE FRONT. MODELS HAVE COME INTO BETTER AGREEMENT
WITH THE TIMING OF THE FRONT BUT THE GFS TRACKS THE UPPER LEVEL
DYNAMICS ACROSS SASKATCHEWAN WHILE THE ECMWF TAKES IT ACROSS
MONTANA. WILL MENTION A SLIGHT CHANCE OF SNOW FOR NOW.
COLD HIGH PRESSURE BUILDS INTO AREA WEDNESDAY NIGHT AND PREVAILS
THROUGH FRIDAY WITH DRY WEATHER. NORTHWEST FLOW ALOFT WILL KEEP
TEMPERATURES ON THE COLD SIDE OF NORMAL. UPPER RIDGE BUILDS INTO
THE AREA BY NEXT WEEKEND WITH A WARMING TREND. FORRESTER
&&
.AVIATION...
IN THE WAKE OF THE COLD FRONT THAT WILL PASS THROUGH THIS EVENING
WEST TO NORTHWEST WINDS WILL RAMP UP AFTER MIDNIGHT AND MAINTAIN
SPEEDS OF 15 TO 25KTS FROM ABOUT 9Z SUNDAY TO 00Z MONDAY.
CEILINGS... AND POSSIBLY VISIBILITY MAY DROP TO MVFR TONIGHT AS
RAIN AND SNOW SHOWERS MOVE OVER THE TERMINALS. BRIEF PERIODS OF
IFR CONDITIONS CAN NOT BE RULED OUT IF A MORE INTENSE BAND MOVES
THROUGH THE AREA. SNOW WILL TAPER OFF SUNDAY MORNING AND AFTERNOON
FOR ALL TERMINALS AS THE SYSTEM EXITS TO THE EAST. AEC/PROTON
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...
LAKE WIND ADVISORY FROM 1 AM TO 5 PM MST SUNDAY FOR FORT PECK
LAKE FOR CENTRAL AND SOUTHEAST PHILLIPS...CENTRAL AND SOUTHERN
VALLEY...GARFIELD...MCCONE...PETROLEUM.
WINTER WEATHER ADVISORY UNTIL 11 AM MST SUNDAY FOR EASTERN
ROOSEVELT...SHERIDAN.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1254 PM EST FRI NOV 15 2013
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL MOVE WEST TO EAST ACROSS THE REGION
THIS AFTERNOON THROUGH TONIGHT. OTHERWISE... SURFACE HIGH PRESSURE
CENTERED OFFSHORE WILL CONTINUE TO PULL ATLANTIC MOISTURE INTO THE
AREA... KEEPING CONSIDERABLE CLOUDS OVER THE AREA THROUGH THE
WEEKEND. A COLD FRONT WILL CROSS THE REGION ON MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 915 AM FRIDAY...
UPDATE AT 1245 PM: HIGH CLOUDS ARE DOING LITTLE TO IMPEDE HEATING
AND OBSERVED TEMPS WERE OUTPACING FORECAST TEMPS LATE THIS
MORNING... SO HAVE ADJUSTED HIGH TEMPS UPWARD TO 61-68. -GIH
FAST MID/HIGH LEVEL SW FLOW AND A PROMINENT APPROACHING WAVE IS
CAUSING MID/HIGH CLOUDS TO OVERSPREAD NC... AND THE DEEP LOW LEVEL
MOISTURE IS JUST ON OUR DOORSTEP... NOTED WELL BY THE CONTRASTING
12Z SOUNDINGS FROM CHS AND GSO. MOISTURE WILL DEEPEN FURTHER WITH
HIGH CLOUDS THICKENING AND LOWERING WITH INCREASING LIFT AS THE
SHORTWAVE TROUGH ALOFT CROSSES THE LOWER MISS VALLEY AND APPROACHES
NC LATER TODAY. CURRENT REGIONAL RADAR SHOWS JUST ISOLATED PATCHY
SPRINKLES OVER CENTRAL/SRN SC INTO NE GA... WHICH THE HRRR BRINGS
NORTHWARD INTO THE SANDHILLS BY EARLY/MID AFTERNOON... BUT THESE
SHOULD BE FAIRLY INCONSEQUENTIAL GIVEN HOW SHALLOW AND WEAKLY FORCED
THEY SHOULD BE. WITH THE MORE SUBSTANTIAL RAIN NOT EXPECTED TO
ARRIVE UNTIL AFTER 5 PM (ACCORDING TO THE LATEST HRRR/RAP WHICH
MATCHES WELL WITH THE CURRENT TEMPORAL TRENDS OF THE UPSTREAM
FORCING)... EXISTING RAIN CHANCE FORECAST LOOKS GOOD... BRINGING
CHANCE POPS INTO THE SW CWA LATER THIS AFTERNOON... EXPANDING ENE AS
WE HEAD INTO THE EVENING. TEMPS ARE QUITE TRICKY CONSIDERING THAT
THESE HIGH CLOUDS THIS MORNING ARE STILL ALLOWING SOME FILTERED
SUNSHINE. CURRENT READINGS ARE WITHIN A DEGREE OR SO OF THE FORECAST
PACE... AND THIS AGREES WELL WITH THE LATEST GRIDDED LAMP FORECAST
GUIDANCE... SO WILL MAKE ONLY MINOR TWEAKS AT MOST TO CURRENT HIGHS
FROM 55 SW TO 63 EAST. -GIH
BY THE EVENING...AIRMASS WILL CONTINUE TO MOISTEN OWING TO THE
APPROACH OF THE UPPER WAVE AND ATTENDANT BRIEF TAP OF GULF MOISTURE
NORTHWARD INTO THE CAROLINAS. WITH PWATS INCREASING TO
1.0-1.25"...DPVA ALONG WITH THE ONGOING WARM AIR ADVECTION/
ISENTROPIC LIFT WILL BRING A QUICK SHOT OF SHOWERS LATE FRIDAY
AFTERNOON/FRIDAY EVENING AND THROUGH THE OVERNIGHT HOURS.
OVER THE LAST COUPLE OF MODEL RUNS...NWP MODEL GUIDANCE HAS
CONTINUED WITH ITS WETTER TREND...PARTICULARLY IN THE EAST
AVERAGING AROUND A QUARTER OF AN INCH OVER THE CAROLINAS LARGELY DUE
TO A WEAK WAVE DEVELOPMENT ALONG THE SE COAST. GIVEN SUCH GOOD
AGREEMENT WILL INTRODUCE CATEGORICAL POPS.
WIDESPREAD CLOUDS...RAIN AND LOW-LEVEL WAA WILL RESULT IN A MUCH
MILDER NIGHT. LOWS IN THE MID 40S WEST TO LOWER 50S EAST. -CBL
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT /...
AS OF 240 AM FRIDAY...
THE SHORTWAVE TROUGH AND ASSOCIATED AREA OF RAIN IS EXPECTED TO
EXIT OFF THE MID-ATLANTIC COAST BY OR SHORTLY AFTER 12Z SATURDAY
WITH PRONOUNCED SUBSIDENCE INCREASING HEIGHTS ALOFT THEREAFTER.
MEANWHILE IN THE LOW-LEVELS...FLOW WILL REMAIN WEAK AND GENERALLY
EAST-SELY. WHILE MEASURABLE PRECIP CHANCES SHOULD BE OVER SHORTLY
AFTER DAYBREAK...WITH NO MEANS TO SCOUR THE LEFT-OVER LOW-LEVEL
MOISTURE...SKIES WILL LOOK OMINOUS THE ENTIRE DAY WITH PREDOMINATELY
BROKEN MVFR CEILING BETWEEN 2-3KT PERSISTING THROUGH MUCH OF THE
DAY...EVOLVING ESSENTIALLY INTO A DRY IN-SITU LIKE CAD. EXPECT THE
WEAK SELY LOW-LEVEL WARM AIR ADVECTION WILL OFFSET THE CLOUD COVER
ENOUGH TO ALLOW TEMPERATURES TO CLIMB INTO THE LOWER 60S...POSSIBLY
MID 60S IN THE EAST. WIDESPREAD STRATUS/LOW CLOUDS ARE EXPECTED
TO CONTINUE OVERNIGHT WITH LOWS IN THE LOWER TO MID 50S.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 238 AM FRIDAY...
LARGE SWINGS IN TEMPERATURES/MOISTURE EXPECTED THIS WEEK...
SUNDAY WILL BEGIN MOIST AND MILD... WITH STRATUS... FOG AND MIST...
COURTESY OF THE RESIDUAL PIEDMONT IN-SITU DAMMING AND LINGERING
SURFACE HIGH PRESSURE RIDGE. THE RIDGE IS FORECAST TO SHIFT OFFSHORE
LATE SUNDAY ALLOWING THE WARMER AIR TO FINALLY REACH THE SURFACE.
BREAKS IN THE OVERCAST SHOULD DEVELOP ACROSS THE SOUTHERN ZONES AND
SPREAD NORTHWARD DURING THE DAY... ESPECIALLY IN THE SANDHILLS...
COASTAL PLAIN AND EASTERN PIEDMONT. HOWEVER... THE TRIAD MAY END UP
REMAINING CLOUDY ALL DAY AS THE NEXT SYSTEM WILL BE APPROACHING LATE
IN THE DAY FROM THE WEST. HIGHS WILL BE DEPENDENT ON THE AMOUNT OF
BREAKS THAT CAN DEVELOP. THEREFORE... EXPECT THE WARMER READINGS
FROM THE SANDHILLS THROUGH THE COASTAL PLAIN WHERE MANY LOCATIONS
SHOULD SEE 70 OR THE LOWER 70S. TO THE NW... FROM RALEIGH TO
GREENSBORO... EXPECT HIGHS TO REMAIN IN THE 60S. DEW POINTS WILL BE
ON THE RISE... WITH HUMID CONDITIONS EXPECTED LATE SUNDAY AND SUNDAY
NIGHT AS THE COLD FRONT APPROACHES INCREASING THE SOUTHERLY FLOW.
THE COLD FRONT IS EXPECTED TO PUSH INTO CENTRAL NC BY 12Z/MONDAY IN
THE FAR NW. THE FRONT IS FORECAST TO PUSH THROUGH DURING THE DAY.
THIS FRONT WILL PUSH THE MILD/MOIST AIR MASS OUT AND REPLACE IT
AGAIN WITH ONE OF ARCTIC ORIGIN. THE DYNAMICS WILL TRACK WELL TO OUR
NORTH. THIS COMBINED WITH THE LACK OF ANY SECONDARY WAVE ON THE
FRONT AS IT MOVES THROUGH SHOULD GREATLY REDUCE THE QPF. EVEN THOUGH
A FEW SHOWERS ARE LIKELY SUNDAY NIGHT INTO THE FIRST HALF OF
MONDAY... QPF IS ONLY AROUND OR LESS THAN 0.25. MODELS CONTINUE TO
SPEED UP THE FRONTAL PASSAGE... AND IT NOW APPEARS THAT THE FRONT
WILL BE INTO THE COASTAL PLAIN BY 18Z/MONDAY... WITH CLEARING IN THE
NW PIEDMONT BY EARLY AFTERNOON. THIS CLEARING SHOULD SPREAD RAPIDLY
SE DURING THE AFTERNOON. SENSIBLE WEATHER... MILD TO WARM SUNDAY
NIGHT WITH A FEW SHOWERS. BREEZY SOUTH-SOUTHWEST WINDS 10-15 MPH.
LOWS IN THE LOWER 60S. A FEW SHOWERS MONDAY MORNING... THEN
CLEARING... BREEZY AND TURNING COLDER DURING THE AFTERNOON. EARLY
HIGHS IN THE MID 60S TO LOWER 70S... FALLING INTO THE 50S WEST AND
LOWER 60S EAST DURING THE AFTERNOON. BREEZY AND COLDER MONDAY NIGHT
AND TUESDAY. MOSTLY CLEAR/SUNNY. LOWS IN THE 30S. HIGHS TUESDAY ONLY
50-55.
WED-THU... STRONG SURFACE HIGH PRESSURE IS FORECAST TO BUILD/EXTEND
DOWN THE EASTERN SEABOARD. ANY INFLUX OF ATLANTIC MOISTURE IS
EXPECTED BEYOND THURSDAY. WEDNESDAY WILL BE THE COLDEST DAY...
FOLLOWED BY A GRADUAL MODIFICATION LATE WEEK. LOWS 25-30. HIGHS
47-52 WED... AND 50-55 THU.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 1250 PM FRIDAY...
FAIRLY HIGH CONFIDENCE THAT SUB-VFR CONDITIONS WILL DOMINATE THROUGH
18Z SAT. ADVERSE AVIATION CONDITIONS ARE EXPECTED TO OVERSPREAD
CENTRAL NC OVER THE NEXT FEW HOURS (BETWEEN NOW AND AND 23Z) FROM
THE WSW... WITH CIGS FALLING FIRST TO MVFR (THIS HAS ALREADY
OCCURRED AT INT/GSO). LIGHT RAIN WILL MOVE IN FROM THE WSW MAINLY
AFTER 22Z (ALTHOUGH A FEW SPRINKLES ARE POSSIBLE BEFORE THEN) WITH
VSBYS BECOMING MAINLY MVFR IN RAIN... AND RAIN WILL BE MORE
WIDESPREAD AT INT/GSO AND AT FAY... WITH A LITTLE LESS COVERAGE AT
RDU/RWI. ONCE THE RAIN EXITS FROM WSW TO ENE... WHICH SHOULD OCCUR
BETWEEN 06Z AND 10Z... CIGS ARE EXPECTED TO DROP TO LIFR WITH IFR
VSBYS IN FOG/STRATUS FOR SEVERAL HOURS. THIS THICK STRATUS WILL THEN
LIFT SLOWLY BETWEEN 14Z AND 17Z TO MVFR (WHILE VSBYS IMPROVE TO
VFR).
LOOKING BEYOND 18Z SAT... MVFR CIGS EXPECTED TO DOMINATE THROUGH THE
REST OF SAT AFTERNOON. LIGHT/VARIABLE SURFACE FLOW AND PLENTY OF
MOISTURE IN PLACE THROUGH THE LOWEST FEW THOUSAND FEET WILL PROMPT
REDEVELOPMENT OF A SURFACE-BASED INVERSION AND IFR/LIFR CONDITIONS
SAT EVENING THROUGH EARLY SUN MORNING. TREND TO MVFR CIGS/VFR VSBYS
EXPECTED LATE SUN MORNING LASTING THROUGH AFTERNOON... THEN ANOTHER
RETURN TO IFR/LIFR CONDITIONS IS POSSIBLE SUN NIGHT WITH BRISK/GUSTY
SW WINDS AND A CHANCE OF SHOWERS. COLD FRONT PASSAGE EXPECTED ON
MONDAY SHOULD INTRODUCE VFR CONDITIONS FOR LATE MON LASTING THROUGH
WED AS HIGH PRESSURE BUILDS IN. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD/CBL
SHORT TERM...CBL
LONG TERM...PWB
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
915 AM EST FRI NOV 15 2013
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL MOVE WEST TO EAST ACROSS THE REGION
THIS AFTERNOON THROUGH TONIGHT. OTHERWISE... SURFACE HIGH PRESSURE
CENTERED OFFSHORE WILL CONTINUE TO PULL ATLANTIC MOISTURE INTO THE
AREA... KEEPING CONSIDERABLE CLOUDS OVER THE AREA THROUGH THE
WEEKEND. A COLD FRONT WILL CROSS THE REGION ON MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 915 AM FRIDAY...
FAST MID/HIGH LEVEL SW FLOW AND A PROMINENT APPROACHING WAVE IS
CAUSING MID/HIGH CLOUDS TO OVERSPREAD NC... AND THE DEEP LOW LEVEL
MOISTURE IS JUST ON OUR DOORSTEP... NOTED WELL BY THE CONTRASTING
12Z SOUNDINGS FROM CHS AND GSO. MOISTURE WILL DEEPEN FURTHER WITH
HIGH CLOUDS THICKENING AND LOWERING WITH INCREASING LIFT AS THE
SHORTWAVE TROUGH ALOFT CROSSES THE LOWER MISS VALLEY AND APPROACHES
NC LATER TODAY. CURRENT REGIONAL RADAR SHOWS JUST ISOLATED PATCHY
SPRINKLES OVER CENTRAL/SRN SC INTO NE GA... WHICH THE HRRR BRINGS
NORTHWARD INTO THE SANDHILLS BY EARLY/MID AFTERNOON... BUT THESE
SHOULD BE FAIRLY INCONSEQUENTIAL GIVEN HOW SHALLOW AND WEAKLY FORCED
THEY SHOULD BE. WITH THE MORE SUBSTANTIAL RAIN NOT EXPECTED TO
ARRIVE UNTIL AFTER 5 PM (ACCORDING TO THE LATEST HRRR/RAP WHICH
MATCHES WELL WITH THE CURRENT TEMPORAL TRENDS OF THE UPSTREAM
FORCING)... EXISTING RAIN CHANCE FORECAST LOOKS GOOD... BRINGING
CHANCE POPS INTO THE SW CWA LATER THIS AFTERNOON... EXPANDING ENE AS
WE HEAD INTO THE EVENING. TEMPS ARE QUITE TRICKY CONSIDERING THAT
THESE HIGH CLOUDS THIS MORNING ARE STILL ALLOWING SOME FILTERED
SUNSHINE. CURRENT READINGS ARE WITHIN A DEGREE OR SO OF THE FORECAST
PACE... AND THIS AGREES WELL WITH THE LATEST GRIDDED LAMP FORECAST
GUIDANCE... SO WILL MAKE ONLY MINOR TWEAKS AT MOST TO CURRENT HIGHS
FROM 55 SW TO 63 EAST. -GIH
BY THE EVENING...AIRMASS WILL CONTINUE TO MOISTEN OWING TO THE
APPROACH OF THE UPPER WAVE AND ATTENDANT BRIEF TAP OF GULF MOISTURE
NORTHWARD INTO THE CAROLINAS. WITH PWATS INCREASING TO
1.0-1.25"...DPVA ALONG WITH THE ONGOING WARM AIR ADVECTION/
ISENTROPIC LIFT WILL BRING A QUICK SHOT OF SHOWERS LATE FRIDAY
AFTERNOON/FRIDAY EVENING AND THROUGH THE OVERNIGHT HOURS.
OVER THE LAST COUPLE OF MODEL RUNS...NWP MODEL GUIDANCE HAS
CONTINUED WITH ITS WETTER TREND...PARTICULARLY IN THE EAST
AVERAGING AROUND A QUARTER OF AN INCH OVER THE CAROLINAS LARGELY DUE
TO A WEAK WAVE DEVELOPMENT ALONG THE SE COAST. GIVEN SUCH GOOD
AGREEMENT WILL INTRODUCE CATEGORICAL POPS.
WIDESPREAD CLOUDS...RAIN AND LOW-LEVEL WAA WILL RESULT IN A MUCH
MILDER NIGHT. LOWS IN THE MID 40S WEST TO LOWER 50S EAST. -CBL
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT /...
AS OF 240 AM FRIDAY...
THE SHORTWAVE TROUGH AND ASSOCIATED AREA OF RAIN IS EXPECTED TO
EXIT OFF THE MID-ATLANTIC COAST BY OR SHORTLY AFTER 12Z SATURDAY
WITH PRONOUNCED SUBSIDENCE INCREASING HEIGHTS ALOFT THEREAFTER.
MEANWHILE IN THE LOW-LEVELS...FLOW WILL REMAIN WEAK AND GENERALLY
EAST-SELY. WHILE MEASURABLE PRECIP CHANCES SHOULD BE OVER SHORTLY
AFTER DAYBREAK...WITH NO MEANS TO SCOUR THE LEFT-OVER LOW-LEVEL
MOISTURE...SKIES WILL LOOK OMINOUS THE ENTIRE DAY WITH PREDOMINATELY
BROKEN MVFR CEILING BETWEEN 2-3KT PERSISTING THROUGH MUCH OF THE
DAY...EVOLVING ESSENTIALLY INTO A DRY IN-SITU LIKE CAD. EXPECT THE
WEAK SELY LOW-LEVEL WARM AIR ADVECTION WILL OFFSET THE CLOUD COVER
ENOUGH TO ALLOW TEMPERATURES TO CLIMB INTO THE LOWER 60S...POSSIBLY
MID 60S IN THE EAST. WIDESPREAD STRATUS/LOW CLOUDS ARE EXPECTED
TO CONTINUE OVERNIGHT WITH LOWS IN THE LOWER TO MID 50S.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 238 AM FRIDAY...
LARGE SWINGS IN TEMPERATURES/MOISTURE EXPECTED THIS WEEK...
SUNDAY WILL BEGIN MOIST AND MILD... WITH STRATUS... FOG AND MIST...
COURTESY OF THE RESIDUAL PIEDMONT IN-SITU DAMMING AND LINGERING
SURFACE HIGH PRESSURE RIDGE. THE RIDGE IS FORECAST TO SHIFT OFFSHORE
LATE SUNDAY ALLOWING THE WARMER AIR TO FINALLY REACH THE SURFACE.
BREAKS IN THE OVERCAST SHOULD DEVELOP ACROSS THE SOUTHERN ZONES AND
SPREAD NORTHWARD DURING THE DAY... ESPECIALLY IN THE SANDHILLS...
COASTAL PLAIN AND EASTERN PIEDMONT. HOWEVER... THE TRIAD MAY END UP
REMAINING CLOUDY ALL DAY AS THE NEXT SYSTEM WILL BE APPROACHING LATE
IN THE DAY FROM THE WEST. HIGHS WILL BE DEPENDENT ON THE AMOUNT OF
BREAKS THAT CAN DEVELOP. THEREFORE... EXPECT THE WARMER READINGS
FROM THE SANDHILLS THROUGH THE COASTAL PLAIN WHERE MANY LOCATIONS
SHOULD SEE 70 OR THE LOWER 70S. TO THE NW... FROM RALEIGH TO
GREENSBORO... EXPECT HIGHS TO REMAIN IN THE 60S. DEW POINTS WILL BE
ON THE RISE... WITH HUMID CONDITIONS EXPECTED LATE SUNDAY AND SUNDAY
NIGHT AS THE COLD FRONT APPROACHES INCREASING THE SOUTHERLY FLOW.
THE COLD FRONT IS EXPECTED TO PUSH INTO CENTRAL NC BY 12Z/MONDAY IN
THE FAR NW. THE FRONT IS FORECAST TO PUSH THROUGH DURING THE DAY.
THIS FRONT WILL PUSH THE MILD/MOIST AIR MASS OUT AND REPLACE IT
AGAIN WITH ONE OF ARCTIC ORIGIN. THE DYNAMICS WILL TRACK WELL TO OUR
NORTH. THIS COMBINED WITH THE LACK OF ANY SECONDARY WAVE ON THE
FRONT AS IT MOVES THROUGH SHOULD GREATLY REDUCE THE QPF. EVEN THOUGH
A FEW SHOWERS ARE LIKELY SUNDAY NIGHT INTO THE FIRST HALF OF
MONDAY... QPF IS ONLY AROUND OR LESS THAN 0.25. MODELS CONTINUE TO
SPEED UP THE FRONTAL PASSAGE... AND IT NOW APPEARS THAT THE FRONT
WILL BE INTO THE COASTAL PLAIN BY 18Z/MONDAY... WITH CLEARING IN THE
NW PIEDMONT BY EARLY AFTERNOON. THIS CLEARING SHOULD SPREAD RAPIDLY
SE DURING THE AFTERNOON. SENSIBLE WEATHER... MILD TO WARM SUNDAY
NIGHT WITH A FEW SHOWERS. BREEZY SOUTH-SOUTHWEST WINDS 10-15 MPH.
LOWS IN THE LOWER 60S. A FEW SHOWERS MONDAY MORNING... THEN
CLEARING... BREEZY AND TURNING COLDER DURING THE AFTERNOON. EARLY
HIGHS IN THE MID 60S TO LOWER 70S... FALLING INTO THE 50S WEST AND
LOWER 60S EAST DURING THE AFTERNOON. BREEZY AND COLDER MONDAY NIGHT
AND TUESDAY. MOSTLY CLEAR/SUNNY. LOWS IN THE 30S. HIGHS TUESDAY ONLY
50-55.
WED-THU... STRONG SURFACE HIGH PRESSURE IS FORECAST TO BUILD/EXTEND
DOWN THE EASTERN SEABOARD. ANY INFLUX OF ATLANTIC MOISTURE IS
EXPECTED BEYOND THURSDAY. WEDNESDAY WILL BE THE COLDEST DAY...
FOLLOWED BY A GRADUAL MODIFICATION LATE WEEK. LOWS 25-30. HIGHS
47-52 WED... AND 50-55 THU.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 620 AM FRIDAY...
STRENGTHENING SWLY MOISTURE ADVECTION IN ADVANCE OF AN APPROACHING
S/W TROUGH THAT WILL MOVE THROUGH THE MID-ATLANTIC REGION TONIGHT
WILL RESULT IN TOP-DOWN MOISTENING WITH MVFR CEILINGS DEVELOPING AS
EARLY AS 18-21Z ACROSS THE WESTERN PIEDMONT...SPREADING EASTWARD
ACROSS THE FORECAST AREA THROUGH THE EVENING HOURS. CONDITIONS ARE
EXPECTED TO DETERIORATE FURTHER OVERNIGHT WITH CEILINGS LOWERING TO
TO IFR-LIFR AS WIDESPREAD RAIN/SHOWERS MOVE EASTWARD THROUGH THE
AREA.
OUTLOOK: ADVERSE AVIATION CONDITIONS WILL CONTINUE THROUGH MUCH OF
THE WEEKEND. WHILE RAIN SHOULD EXIT THE AREA SHORTLY AFTER 12Z
SATURDAY...SUB-VFR CEILINGS(LIKELY MVFR)WILL LIKELY PERSIST THROUGH
THE DAY...BEFORE LOWERING TO IFR-LIFR SATURDAY NIGHT. VFR CONDITIONS
ARE EXPECTED TO RETURN BRIEFLY ON SUNDAY...THEN DROP BACK TO MAINLY
IFR SUN EVENING THROUGH MONDAY AS A BAND OF SHOWERS/STORMS ACCOMPANY
A COLD FRONTAL PASSAGE FROM THE WEST. VFR CONDITIONS SHOULD RESUME
MON NIGHT/TUE.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD/CBL
SHORT TERM...CBL
LONG TERM...PWB
AVIATION...CBL
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
114 PM CST FRI NOV 15 2013
.UPDATE...
ISSUED AT 113 PM CST FRI NOV 15 2013
DISCUSSION UPDATED FOR AVIATION DISCUSSION ONLY.
UPDATE ISSUED AT 950 AM CST FRI NOV 15 2013
VIS SAT SHOWING MOSTLY CLEAR SKIES OVER CWA...WITH EXCEPTION OF
SOME LINGERING STRATUS OVER PARTS OF BELTRAMI COUNTY. MOST
SIGNIFICANT CHANGE WILL BE GOING CLEAR SKIES FOR REMAINDER OF AM
AND INTO THE AFTN...THEN TIMING IN CLOUDS OVER SD. ALSO HAVE
REMOVED THE POPS FOR THIS AFTN FOR SAME REASONING I REMOVED THEM
YESTERDAY. THERE IS A DECENT OMEGA FIELD WITH COLUMN SATURATED IN
THE MID LEVELS...HOWEVER A VERY DRY LAYER IN THE 925 TO 850 LAYER.
SATURATED LAYER WOULD INDICATE SNOW MELTING AS IT FALLS THROUGH
THE WARM/DRY LAYER BENEATH...AND DO NOT SEE MEASURABLE PRECIP AT
THE SFC. SINCE THIS PERIOD HAS FLIP FLOPPED SEVERAL TIMES...DID
KEEP IN SPRINKLES FOR THOSE AREAS. NOTE THE NAM DOES SHOW LOWER
MID LEVEL CIGS THAN YESTERDAYS 12Z RUN...AND NOW THE 300 K
ISENTROPIC LAYER IS WHERE SATURATED CONDENSATION PRESSURE
DEFICITS BEGIN AS OPPOSED TO THE 305 K ON YESTERDAYS RUN. SO THE
NAM IS SATURATING COLUMN CLOSER TO SFC THAN THE GFS...WHICH HAS
NOT CHANGED MUCH SINCE YESTERDAYS RUN. HAVE ALSO CHANGED FROM RAIN
TO DRIZZLE POPS IN THE EAST AFT 06Z (SAME REASONING AS YESTERDAY).
UPDATE ISSUED AT 703 AM CST FRI NOV 15 2013
FOG IN VALLEY CITY TO COOPERSTOWN AREA OTHERWISE PATCHY FOG THAT
WAS AROUND TVF/CKN HAS MOVED OUT. STARTING OFF PRETTY CLEAR IN ALL
BUT A FEW AREAS IN NRN MN...SO WILL ADJUST SKY COVER. LATEST HRRR
STILL SHOWS A LITTLE LIGHT PRECIP VERY LATE TODAY IN SE ND SO WILL
KEEP THAT LOW POP. BUT OTHERWISE GOOD DEAL OF SUN AND HRRR SHOWS
LOW 50S IN SW FCST WITH UPPER 40S IN THE RRV AND LOWER TO MID 40S
IN BAUDETTE REGION WHICH IS CLOSE TO GOING FCST.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 342 AM CST FRI NOV 15 2013
LOW CLOUD COVER EXITING THE NRN FCST AREA AT 09Z WITH AREAS OF MID
LEVEL CLOUDS REPLACING IT. BUT OVERALL THE TREND IS FOR LESS CLOUD
COVER. MAINLY CLEAR DVL-GFK-PKD SOUTHWARD AND THERE IS SOME PATCHY
FOG. EXPECT A FAIRLY SUNNY IN MOST AREAS TODAY...EXCEPT PERHAPS
THE FAR NORTH...AND SOUTH WINDS WILL INCREASE TO THE 8 TO 13 KT
RANGE. MODELS REMAIN IN SOMEWHAT AGREEMENT IN SHOWING DEVELOPMENT
OF MID LEVEL MOISTURE OVER CNTRL SD 18Z FRI THEN IT SPREADS
NORTHEAST INTO SE ND BY 00Z AND THEN INTO NRN MN THIS EVE. WILL
MAINTAIN SOME LOW POPS FOR A LIGHT SHOWER OR SPRINKLE THAT MAY
OCCUR WITH THIS MID LEVEL MOISTURE. AREA SEEMS TO BE AIDED BY THE
NRN EDGE OF THE 850 MB JET TOWARD 00Z OVER SE ND INTO PARTS OF NRN
MN.
MILD DAY TODAY WITH HIGHS WELL INTO THE 40S EVEN SOME LOW 50S PSBL
SW FCST AREA.
QUIET TONIGHT...BUT GFS/NAM MOS AND 925 MB RH SHOWS SOME LOW LEVEL
MOISTURE AND PSBL LOWER CLOUDS SPREADING NORTH IN LOW LEVEL JET
THRU PARTS OF MINNESOTA INTO SE FCST AREA LATE TONIGHT INTO
SATURDAY MORNING. REGULATED ANY SMALL CHC OF LIGHT RAIN TO ERN
FCST AREA IN THIS MOISTURE REGIME. ANOTHER MILD DAY THOUGH NOT AS
WARM IN SOME AREAS DUE TO EXPECTED CLOUD COVER. BUT STILL HIGHS IN
THE 40S.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 342 AM CST FRI NOV 15 2013
SATURDAY NIGHT INTO SUNDAY IS COMPLEX BUT OVERALL WEATHER IMPACTS
WILL BE MINIMAL. ALL MODELS SHOW DEVELOPMENT OF A 500 MB TROUGH
OVER THE NRN PLAINS AHEAD OF MAIN SHORT WAVE WHICH WILL DIVE INTO
THE CNTRL ROCKIES. COLD FRONT WILL DROP SOUTH DOWN THE FRONT
RANGE...EDGING INTO NW-NCNTRL ND SAT NIGHT. TO SOME DEGREE...LOOKS
LIKE A DEVELOPMENT OF LOW PRESSURE OVER NE SD INTO NRN MN SAT EVE
WITH DEVELOPMENT OF LIGHT PRECIP WEST OF THIS LOW OVER ERN ND INTO
NW MN AS SAT NIGHT PROGRESSES. THEN THIS SFC LOW WILL MOVE
NORTHEAST INTO WRN ONTARIO AND MAIN COLD FRONT WILL THEN DROP THRU
THE THE FCST AREA DAYTIME SUNDAY. PTYPE WOULD INDICATE INITIALLY
RAIN...THEN BECOMING MIXED WITH OR CHANGING TO LIGHT SNOW LATE SAT
NIGHT INTO SUNDAY MORNING. COULD BE AN INCH OR TWO MAX IN NW MN
WHERE BETTER MOISTURE WILL BE AS COLD AIR MOVES IN. BEST CHC OF
THIS TVF-ROX-BDE-BJI REGION. ANY LEFTOVER LIGHT SNOW WILL PUSH
EAST OF THE AREA SUN AFTN-EVE. OVERALL THOUGH AMOUNT OF COLD AIR
IS LESS THAN ADVERTISED A FEW DAYS AGO...SO NOTHING LIKE THE
DEPARTURES EXPERIENCED WITH THE LAST OUTBREAK.
FOR THE MONDAY THROUGH THURSDAY PERIOD...LONG WAVE TROUGH AXIS
FROM NORTHERN CANADA TO THE US ROCKIES AT THE BEGINNING OF THE
PERIOD BECOMES ZONAL ACROSS SOUTHERN CANADA AND THE NORTHERN US BY
THE END OF THE PERIOD.
MODELS ARE NOT AGREEING VERY WELL THIS PERIOD. AT 84 HOURS THE ECMWF
HAD A HIGHER AMPLITUDE SOLUTION THAN THE GFS. THE ECMWF AND GFS ARE
180 DEGREES OUT OF PHASE ON WED. GFS ENSEMBLE, OPERATIONAL GFS AND
ECMWF HAVE BEEN TRENDING TO A MORE ZONAL FLOW THIS PERIOD COMPARED
TO PREVIOUS RUNS. ON WED, BOTH THE GFS AND THE ECMWF HAVE BEEN
SHIFTING COOLER AIR SOUTH EACH RUN TO SUPPORT THE ZONAL PATTERN.
LITTLE OR NO PRECIPITATION EXPECTED THIS PERIOD. HOWEVER THIS MAY
CHANGE IF MODELS CONTINUE TO SHIFT SOUTH. CONFIDENCE IS NOT HIGH IN
FAST FLOW PATTERNS.
HIGH TEMPS TWEAKED UP OR DOWN A DEGREE OR SO THIS PERIOD. LOWS
INCREASED ABOUT TWO DEGREES FROM YESTERDAYS RUN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 113 PM CST FRI NOV 15 2013
EXPECT VFR CONDITIONS WITH PERHAPS SOME MID CLOUDS AND SPRINKLES FOR
THE NORTHERN AREAS THIS EVENING...BUT WON/T MENTION ANY PRECIP.
SOUTHERLY WINDS COULD GUST UP TO NEAR 20 KT NEAR KDVL/KGFK THIS
AFTERNOON FOR A FEW HOURS...BUT WINDS SHOULD REMAIN BELOW 20KT FOR
THE MOST PART.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...SPEICHER
SHORT TERM...RIDDLE
LONG TERM...HOPPES/RIDDLE
AVIATION...DK
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
950 AM CST FRI NOV 15 2013
.UPDATE...
ISSUED AT 950 AM CST FRI NOV 15 2013
VIS SAT SHOWING MOSTLY CLEAR SKIES OVER CWA...WITH EXCEPTION OF
SOME LINGERING STRATUS OVER PARTS OF BELTRAMI COUNTY. MOST
SIGNIFICANT CHANGE WILL BE GOING CLEAR SKIES FOR REMAINDER OF AM
AND INTO THE AFTN...THEN TIMING IN CLOUDS OVER SD. ALSO HAVE
REMOVED THE POPS FOR THIS AFTN FOR SAME REASONING I REMOVED THEM
YESTERDAY. THERE IS A DECENT OMEGA FIELD WITH COLUMN SATURATED IN
THE MID LEVELS...HOWEVER A VERY DRY LAYER IN THE 925 TO 850 LAYER.
SATURATED LAYER WOULD INDICATE SNOW MELTING AS IT FALLS THROUGH
THE WARM/DRY LAYER BENEATH...AND DO NOT SEE MEASURABLE PRECIP AT
THE SFC. SINCE THIS PERIOD HAS FLIP FLOPPED SEVERAL TIMES...DID
KEEP IN SPRINKLES FOR THOSE AREAS. NOTE THE NAM DOES SHOW LOWER
MID LEVEL CIGS THAN YESTERDAYS 12Z RUN...AND NOW THE 300 K
ISENTROPIC LAYER IS WHERE SATURATED CONDENSATION PRESSURE
DEFICITS BEGIN AS OPPOSED TO THE 305 K ON YESTERDAYS RUN. SO THE
NAM IS SATURATING COLUMN CLOSER TO SFC THAN THE GFS...WHICH HAS
NOT CHANGED MUCH SINCE YESTERDAYS RUN. HAVE ALSO CHANGED FROM RAIN
TO DRIZZLE POPS IN THE EAST AFT 06Z (SAME REASONING AS YESTERDAY).
UPDATE ISSUED AT 703 AM CST FRI NOV 15 2013
FOG IN VALLEY CITY TO COOPERSTOWN AREA OTHERWISE PATCHY FOG THAT
WAS AROUND TVF/CKN HAS MOVED OUT. STARTING OFF PRETTY CLEAR IN ALL
BUT A FEW AREAS IN NRN MN...SO WILL ADJUST SKY COVER. LATEST HRRR
STILL SHOWS A LITTLE LIGHT PRECIP VERY LATE TODAY IN SE ND SO WILL
KEEP THAT LOW POP. BUT OTHERWISE GOOD DEAL OF SUN AND HRRR SHOWS
LOW 50S IN SW FCST WITH UPPER 40S IN THE RRV AND LOWER TO MID 40S
IN BAUDETTE REGION WHICH IS CLOSE TO GOING FCST.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 342 AM CST FRI NOV 15 2013
LOW CLOUD COVER EXITING THE NRN FCST AREA AT 09Z WITH AREAS OF MID
LEVEL CLOUDS REPLACING IT. BUT OVERALL THE TREND IS FOR LESS CLOUD
COVER. MAINLY CLEAR DVL-GFK-PKD SOUTHWARD AND THERE IS SOME PATCHY
FOG. EXPECT A FAIRLY SUNNY IN MOST AREAS TODAY...EXCEPT PERHAPS
THE FAR NORTH...AND SOUTH WINDS WILL INCREASE TO THE 8 TO 13 KT
RANGE. MODELS REMAIN IN SOMEWHAT AGREEMENT IN SHOWING DEVELOPMENT
OF MID LEVEL MOISTURE OVER CNTRL SD 18Z FRI THEN IT SPREADS
NORTHEAST INTO SE ND BY 00Z AND THEN INTO NRN MN THIS EVE. WILL
MAINTAIN SOME LOW POPS FOR A LIGHT SHOWER OR SPRINKLE THAT MAY
OCCUR WITH THIS MID LEVEL MOISTURE. AREA SEEMS TO BE AIDED BY THE
NRN EDGE OF THE 850 MB JET TOWARD 00Z OVER SE ND INTO PARTS OF NRN
MN.
MILD DAY TODAY WITH HIGHS WELL INTO THE 40S EVEN SOME LOW 50S PSBL
SW FCST AREA.
QUIET TONIGHT...BUT GFS/NAM MOS AND 925 MB RH SHOWS SOME LOW LEVEL
MOISTURE AND PSBL LOWER CLOUDS SPREADING NORTH IN LOW LEVEL JET
THRU PARTS OF MINNESOTA INTO SE FCST AREA LATE TONIGHT INTO
SATURDAY MORNING. REGULATED ANY SMALL CHC OF LIGHT RAIN TO ERN
FCST AREA IN THIS MOISTURE REGIME. ANOTHER MILD DAY THOUGH NOT AS
WARM IN SOME AREAS DUE TO EXPECTED CLOUD COVER. BUT STILL HIGHS IN
THE 40S.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 342 AM CST FRI NOV 15 2013
SATURDAY NIGHT INTO SUNDAY IS COMPLEX BUT OVERALL WEATHER IMPACTS
WILL BE MINIMAL. ALL MODELS SHOW DEVELOPMENT OF A 500 MB TROUGH
OVER THE NRN PLAINS AHEAD OF MAIN SHORT WAVE WHICH WILL DIVE INTO
THE CNTRL ROCKIES. COLD FRONT WILL DROP SOUTH DOWN THE FRONT
RANGE...EDGING INTO NW-NCNTRL ND SAT NIGHT. TO SOME DEGREE...LOOKS
LIKE A DEVELOPMENT OF LOW PRESSURE OVER NE SD INTO NRN MN SAT EVE
WITH DEVELOPMENT OF LIGHT PRECIP WEST OF THIS LOW OVER ERN ND INTO
NW MN AS SAT NIGHT PROGRESSES. THEN THIS SFC LOW WILL MOVE
NORTHEAST INTO WRN ONTARIO AND MAIN COLD FRONT WILL THEN DROP THRU
THE THE FCST AREA DAYTIME SUNDAY. PTYPE WOULD INDICATE INITIALLY
RAIN...THEN BECOMING MIXED WITH OR CHANGING TO LIGHT SNOW LATE SAT
NIGHT INTO SUNDAY MORNING. COULD BE AN INCH OR TWO MAX IN NW MN
WHERE BETTER MOISTURE WILL BE AS COLD AIR MOVES IN. BEST CHC OF
THIS TVF-ROX-BDE-BJI REGION. ANY LEFTOVER LIGHT SNOW WILL PUSH
EAST OF THE AREA SUN AFTN-EVE. OVERALL THOUGH AMOUNT OF COLD AIR
IS LESS THAN ADVERTISED A FEW DAYS AGO...SO NOTHING LIKE THE
DEPARTURES EXPERIENCED WITH THE LAST OUTBREAK.
FOR THE MONDAY THROUGH THURSDAY PERIOD...LONG WAVE TROUGH AXIS
FROM NORTHERN CANADA TO THE US ROCKIES AT THE BEGINNING OF THE
PERIOD BECOMES ZONAL ACROSS SOUTHERN CANADA AND THE NORTHERN US BY
THE END OF THE PERIOD.
MODELS ARE NOT AGREEING VERY WELL THIS PERIOD. AT 84 HOURS THE ECMWF
HAD A HIGHER AMPLITUDE SOLUTION THAN THE GFS. THE ECMWF AND GFS ARE
180 DEGREES OUT OF PHASE ON WED. GFS ENSEMBLE, OPERATIONAL GFS AND
ECMWF HAVE BEEN TRENDING TO A MORE ZONAL FLOW THIS PERIOD COMPARED
TO PREVIOUS RUNS. ON WED, BOTH THE GFS AND THE ECMWF HAVE BEEN
SHIFTING COOLER AIR SOUTH EACH RUN TO SUPPORT THE ZONAL PATTERN.
LITTLE OR NO PRECIPITATION EXPECTED THIS PERIOD. HOWEVER THIS MAY
CHANGE IF MODELS CONTINUE TO SHIFT SOUTH. CONFIDENCE IS NOT HIGH IN
FAST FLOW PATTERNS.
HIGH TEMPS TWEAKED UP OR DOWN A DEGREE OR SO THIS PERIOD. LOWS
INCREASED ABOUT TWO DEGREES FROM YESTERDAYS RUN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 703 AM CST FRI NOV 15 2013
PATCHY FOG WILL BURN OFF SOON AFTER SUNRISE AND AIRMASS JUST ABOVE
SFC IS WELL MIXED WITH SOUTHERLY WINDS NR 10 KTS. EXPECT RESIDUAL
LOWER CLOUDS IN THE BEMIDJI-PARK RAPIDS AREA TO ALSO SCATTER OUT
MORE AS MORNING PROGRESSES. OTHERWISE JUST SOME CIRRUS OR MID
CLOUD MAINLY THIS AFTN INTO TONIGHT. RISK OF LOWER CIGS RETURNING
FROM THE SOUTH OVER BJI AREA LATE TONIGHT. WINDS TODAY SOUTH 8 TO
15 KTS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...SPEICHER
SHORT TERM...RIDDLE
LONG TERM...HOPPES/RIDDLE
AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
708 AM CST FRI NOV 15 2013
.UPDATE...
ISSUED AT 703 AM CST FRI NOV 15 2013
FOG IN VALLEY CITY TO COOPERSTOWN AREA OTHERWISE PATCHY FOG THAT
WAS AROUND TVF/CKN HAS MOVED OUT. STARTING OFF PRETTY CLEAR IN ALL
BUT A FEW AREAS IN NRN MN...SO WILL ADJUST SKY COVER. LATEST HRRR
STILL SHOWS A LITTLE LIGHT PRECIP VERY LATE TODAY IN SE ND SO WILL
KEEP THAT LOW POP. BUT OTHERWISE GOOD DEAL OF SUN AND HRRR SHOWS
LOW 50S IN SW FCST WITH UPPER 40S IN THE RRV AND LOWER TO MID 40S
IN BAUDETTE REGION WHICH IS CLOSE TO GOING FCST.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 342 AM CST FRI NOV 15 2013
LOW CLOUD COVER EXITING THE NRN FCST AREA AT 09Z WITH AREAS OF MID
LEVEL CLOUDS REPLACING IT. BUT OVERALL THE TREND IS FOR LESS CLOUD
COVER. MAINLY CLEAR DVL-GFK-PKD SOUTHWARD AND THERE IS SOME PATCHY
FOG. EXPECT A FAIRLY SUNNY IN MOST AREAS TODAY...EXCEPT PERHAPS
THE FAR NORTH...AND SOUTH WINDS WILL INCREASE TO THE 8 TO 13 KT
RANGE. MODELS REMAIN IN SOMEWHAT AGREEMENT IN SHOWING DEVELOPMENT
OF MID LEVEL MOISTURE OVER CNTRL SD 18Z FRI THEN IT SPREADS
NORTHEAST INTO SE ND BY 00Z AND THEN INTO NRN MN THIS EVE. WILL
MAINTAIN SOME LOW POPS FOR A LIGHT SHOWER OR SPRINKLE THAT MAY
OCCUR WITH THIS MID LEVEL MOISTURE. AREA SEEMS TO BE AIDED BY THE
NRN EDGE OF THE 850 MB JET TOWARD 00Z OVER SE ND INTO PARTS OF NRN
MN.
MILD DAY TODAY WITH HIGHS WELL INTO THE 40S EVEN SOME LOW 50S PSBL
SW FCST AREA.
QUIET TONIGHT...BUT GFS/NAM MOS AND 925 MB RH SHOWS SOME LOW LEVEL
MOISTURE AND PSBL LOWER CLOUDS SPREADING NORTH IN LOW LEVEL JET
THRU PARTS OF MINNESOTA INTO SE FCST AREA LATE TONIGHT INTO
SATURDAY MORNING. REGULATED ANY SMALL CHC OF LIGHT RAIN TO ERN
FCST AREA IN THIS MOISTURE REGIME. ANOTHER MILD DAY THOUGH NOT AS
WARM IN SOME AREAS DUE TO EXPECTED CLOUD COVER. BUT STILL HIGHS IN
THE 40S.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 342 AM CST FRI NOV 15 2013
SATURDAY NIGHT INTO SUNDAY IS COMPLEX BUT OVERALL WEATHER IMPACTS
WILL BE MINIMAL. ALL MODELS SHOW DEVELOPMENT OF A 500 MB TROUGH
OVER THE NRN PLAINS AHEAD OF MAIN SHORT WAVE WHICH WILL DIVE INTO
THE CNTRL ROCKIES. COLD FRONT WILL DROP SOUTH DOWN THE FRONT
RANGE...EDGING INTO NW-NCNTRL ND SAT NIGHT. TO SOME DEGREE...LOOKS
LIKE A DEVELOPMENT OF LOW PRESSURE OVER NE SD INTO NRN MN SAT EVE
WITH DEVELOPMENT OF LIGHT PRECIP WEST OF THIS LOW OVER ERN ND INTO
NW MN AS SAT NIGHT PROGRESSES. THEN THIS SFC LOW WILL MOVE
NORTHEAST INTO WRN ONTARIO AND MAIN COLD FRONT WILL THEN DROP THRU
THE THE FCST AREA DAYTIME SUNDAY. PTYPE WOULD INDICATE INITIALLY
RAIN...THEN BECOMING MIXED WITH OR CHANGING TO LIGHT SNOW LATE SAT
NIGHT INTO SUNDAY MORNING. COULD BE AN INCH OR TWO MAX IN NW MN
WHERE BETTER MOISTURE WILL BE AS COLD AIR MOVES IN. BEST CHC OF
THIS TVF-ROX-BDE-BJI REGION. ANY LEFTOVER LIGHT SNOW WILL PUSH
EAST OF THE AREA SUN AFTN-EVE. OVERALL THOUGH AMOUNT OF COLD AIR
IS LESS THAN ADVERTISED A FEW DAYS AGO...SO NOTHING LIKE THE
DEPARTURES EXPERIENCED WITH THE LAST OUTBREAK.
FOR THE MONDAY THROUGH THURSDAY PERIOD...LONG WAVE TROUGH AXIS
FROM NORTHERN CANADA TO THE US ROCKIES AT THE BEGINNING OF THE
PERIOD BECOMES ZONAL ACROSS SOUTHERN CANADA AND THE NORTHERN US BY
THE END OF THE PERIOD.
MODELS ARE NOT AGREEING VERY WELL THIS PERIOD. AT 84 HOURS THE ECMWF
HAD A HIGHER AMPLITUDE SOLUTION THAN THE GFS. THE ECMWF AND GFS ARE
180 DEGREES OUT OF PHASE ON WED. GFS ENSEMBLE, OPERATIONAL GFS AND
ECMWF HAVE BEEN TRENDING TO A MORE ZONAL FLOW THIS PERIOD COMPARED
TO PREVIOUS RUNS. ON WED, BOTH THE GFS AND THE ECMWF HAVE BEEN
SHIFTING COOLER AIR SOUTH EACH RUN TO SUPPORT THE ZONAL PATTERN.
LITTLE OR NO PRECIPITATION EXPECTED THIS PERIOD. HOWEVER THIS MAY
CHANGE IF MODELS CONTINUE TO SHIFT SOUTH. CONFIDENCE IS NOT HIGH IN
FAST FLOW PATTERNS.
HIGH TEMPS TWEAKED UP OR DOWN A DEGREE OR SO THIS PERIOD. LOWS
INCREASED ABOUT TWO DEGREES FROM YESTERDAYS RUN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 703 AM CST FRI NOV 15 2013
PATCHY FOG WILL BURN OFF SOON AFTER SUNRISE AND AIRMASS JUST ABOVE
SFC IS WELL MIXED WITH SOUTHERLY WINDS NR 10 KTS. EXPECT RESIDUAL
LOWER CLOUDS IN THE BEMIDJI-PARK RAPIDS AREA TO ALSO SCATTER OUT
MORE AS MORNING PROGRESSES. OTHERWISE JUST SOME CIRRUS OR MID
CLOUD MAINLY THIS AFTN INTO TONIGHT. RISK OF LOWER CIGS RETURNING
FROM THE SOUTH OVER BJI AREA LATE TONIGHT. WINDS TODAY SOUTH 8 TO
15 KTS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...RIDDLE
SHORT TERM...RIDDLE
LONG TERM...HOPPES/RIDDLE
AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
623 AM CST FRI NOV 15 2013
.UPDATE...FOR 12Z AVIATION FORECAST
&&
.AVIATION...
MOISTURE TRANSPORT BEGINNING TO STREAM NORTHWARD FROM GULF REGION
AS CAN BE SEEN IN LATEST 11U-3.9U SATELLITE LOOP AND LATEST RUC 850
DEWPOINTS WHICH SHOW AN AXIS FROM NORTHWEST ALABAMA INTO THE UPPER
CUMBERLAND. UPPER DISTURBANCE OVER EASTERN OKLAHOMA HEADING THIS
WAY TODAY. CURRENTLY BAND OF SHOWERS EXTENDS ALONG THE MISSISSIPPI
RIVER THAT WILL CONTINUE TO WORK THIS WAY REACHING THE TENNESSEE
RIVER AROUND 15Z AND INTERSTATE 65 BY 17Z. LOWER LEVELS OF
TROPOSPHERE STILL VERY DRY SO EXPECT IT MAY TAKE A WHILE TO SEE
MUCH IN THE WAY OF RAIN HITTING THE GROUND. MVFR CLOUD DECK WILL
DEVELOP DURING THE AFTERNOON AND LOWER DURING THE EVENING WHLE
REMAINING OVERNIGHT. EXPECT TO SEE IFR CONDITIONS AT CROSSVILLE
TONIGHT MAINLY DUE TO CEILINGS.
BOYD
&&
.PREV DISCUSSION... /ISSUED 402 AM CST FRI NOV 15 2013/
SHORT TERM...
AN APPROACHING 500 MB SHORTWAVE AND ITS RESULTANT SHOWER ACTIVITY
IS THE FOCUS OF THE FIRST 24 HOURS. THE LOW LEVEL ATMOSPHERE IS
QUITE DRY ACCORDING TO FORECAST SOUNDINGS AND ALTHOUGH DEWS ARE
RISING THIS MORNING...BELIEVE THE MODELS RAPID MOISTENING OF THE
LOW AND MID LEVELS IS RATHER AGGRESSIVE. WITH VERY STABLE
CONDITIONS THROUGH 18Z TODAY AND THE AFOREMENTIONED DRY AIR IN
PLACE...LEFT POPS SLGT OR BELOW UNTIL 18Z. BY THE AFTERNOON
HOURS...MOST MODEL DEPICTIONS SHOW PRECIP SCATTERED THROUGHOUT THE
AREA. THUS HAVE INCLUDED CHC POPS THROUGHOUT THE CWA DURING THE
AFTERNOON AND EVENING HOURS. THIS SHORTWAVE SHOULD CLEAR THE CWA
BY 06Z TONIGHT.
LONG TERM...
OUR NEXT SYSTEM OF INTEREST WILL BE A POTENT UPPER LOW PROGGED TO
PASS DIRECTLY OVER THE GREAT LAKES. SFC CYCLOGENESIS WILL BEGIN
OFF THE LEE OF THE ROCKIES SATURDAY NIGHT AND THE LOW WILL QUICKLY
TRANSLATE NEWD TO THE GREAT LAKES BY 18Z SUNDAY. THIS SHOULD
RESULT IN A LARGE WARM SECTOR RANGING FROM ESSENTIALLY THE ENTIRE
OH AND TN VALLEY. AS OF RIGHT NOW...SPC HAS THIS BROAD AREA IN A
SLIGHT RISK. AT THE MOMENT...IT WOULD APPEAR THE MAIN THREAT OF
THIS SYSTEM WILL BE TO OUR NORTH AS MOST SIGNIFICANT UPPER LEVEL
ENERGY PHASED WITH 850 LLJ ENERGY WILL BE IN THE KY/IN/OH AREA.
HOWEVER...A MESSY MIX OF 35+ KT 0-6 KM BULK SHEAR...NEGATIVE LI
VALUES...AND CAPE VALUES IN THE 300-500 J/KG RANGE DO APPEAR
FAVORABLE FOR A SEVERE THREAT SUNDAY AFTERNOON.
TWO THINGS APPEAR TO BE BIG DIFFERENCE MAKERS...ONE WOULD BE IF
THIS UPPER LOW CAN DIG ANY FURTHER SOUTH...IF SO...THE ROBUST
DYNAMICAL LIFT WOULD COINCIDE WITH A PRETTY UNSTABLE ATMOSPHERE
AND UPSCALE GROWTH WOULD BE VERY LIKELY. EVEN STILL...A SEVERE
THREAT STILL SEEMS POSSIBLE SUNDAY AFTERNOON. THE OTHER DIFFERENCE
MAKER WOULD BE MORNING SHOWER ACTIVITY. FORECAST SOUNDINGS ARE
VERY MOIST BY 12Z SUNDAY...AND WITH A VERY STRONG LLJ IN PLACE AT
THAT TIME...SCATTERED RAIN SHOWERS LOOK TO BE SCATTERED OUT IN
FRONT OF THE MAIN SYSTEM. AT THE VERY LEAST...CLOUDY SKIES WOULD
BE IN PLACE. THIS WOULD MAKE THE INSTABILITY DIFFICULT TO REALIZE
THROUGHOUT THE DAY. HENCE THE USE OF THE WORD MESSY EARLIER.
TO SUM UP...CONFIDENCE IS NOT HIGH ON WHAT EXACTLY TO EXPECT WITH
THIS SYSTEM JUST YET. AM HOPING LATER MODEL RUNS PAINT A CLEARER
PICTURE. HOWEVER...FOR NOW SCATTERED SHOWERS EVOLVING INTO A
ISOLATED DISCRETE SEVERE EVENT...EVENTUALLY ORGANIZING INTO A LINE
WITH A PRIMARILY STRAIGHT LINE WIND THREAT IS THE BEST GUESS. CANT
RULE OUT A T WORD WITH THE HIGH HELICITY AND SHEAR BUT UNSETTLED
ON THE THERMODYNAMIC POTENTIAL SO CONFIDENCE IS LOW ON THAT.
AFTER THE SYSTEM CLEARS OUT...COOL AND DRY CONDITIONS TO PERSIST
THROUGH THE WEEK. THE NEXT SYSTEM WILL APPROACH THE FOLLOWING
WEEKEND WITH CONSIDERABLE MODEL DISCREPANCY. THUS LEFT MOST OF
EXTENDED BEYOND MONDAY LARGELY UNCHANGED FROM PREVIOUS FORECAST.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
BOYD
01
AREA FORECAST DISCUSSION
NWS AMARILLO TX
232 PM CST FRI NOV 15 2013
.DISCUSSION...
FORECAST CHALLENGES OVER THE NEXT 24 HOURS INCLUDE CHANCES FOR ANY
CONVECTION TONIGHT AND WIND ADVISORY PROSPECTS FOR SATURDAY. AGREE
WITH WFO LUBBOCK AS THE HRRR AND EVEN THE RUC SHOWING PRECIP MOVING
NORTH AND EAST OUT OF NEW MEXICO THIS EVENING THROUGH TONIGHT ACROSS
MAINLY PARTS OF THE TEXAS PANHANDLE. THIS CONVECTION ASSOCIATED WITH
A SHORTWAVE LOCATED OVER WESTERN AND SOUTHERN NEW MEXICO AND FORECAST
TO LIFT NORTH AND EAST INTO THE SOUTHWEST AND CENTRAL TEXAS PANHANDLE
AFTER 00Z AND 03Z SATURDAY. CONFIDENCE NOT HIGH ENOUGH TO MENTION
THUNDER...BUT WILL INTRODUCE ISOLATED SHOWERS FOR THE TONIGHT
PERIOD. CONSIDERABLE MID AND HIGH LEVEL CLOUDINESS TONIGHT INTO
SATURDAY MAY PUT A DAMPER ON MIXING THE STRONGER WINDS ALOFT AFTER
15Z TO 17Z SATURDAY...HOWEVER AGREE THAT WIND ADVISORY CRITERIA MAY
BE MET ON THE CAPROCK BY 18Z SATURDAY. CONFIDENCE JUST NOT HIGH
ENOUGH ON TIMING AND LOCATION TO ISSUE A WIND ADVISORY AT THIS TIME.
FEEL THAT A NARROW WINDOW OF WIND ADVISORY CRITERIA POSSIBLE BETWEEN
ABOUT 17Z AND 21Z SATURDAY...WITH WIND SPEEDS GRADUALLY DECREASING
THROUGH THE REMAINDER OF THE AFTERNOON.
COLD FRONT EXPECTED TO PUSH SOUTH AND WEST THROUGH THE PANHANDLES
DURING THE DAY SUNDAY BRINGING COOLER CONDITIONS EARLY NEXT WEEK.
MODERATING TEMPERATURES BY THE MIDDLE OF NEXT WEEK BEFORE ANOTHER
COLD FRONT MOVES THROUGH THE FORECAST AREA LATE NEXT WEEK. MEDIUM
RANGE MODELS INDICATING POSSIBLE PRECIP CHANCES BY THURSDAY NIGHT OR
FRIDAY MAINLY ACROSS THE EASTERN SECTIONS OF THE PANHANDLES AS AN
UPPER TROUGH APPROACHES FROM THE FOUR CORNERS AND SOUTHERN ROCKIES.
WILL HOLD OFF INTRODUCING ANY POPS IN THE THURSDAY TO FRIDAY TIME
FRAME...BUT WILL BUMP UP POPS TO AROUND 10 PERCENT OR SO.
SCHNEIDER
&&
.FIRE WEATHER...
MARGINAL ELEVATED FIRE WEATHER CONDITIONS WILL PERSIST UNTIL AROUND
SUNSET THIS EVENING WITH THE 20 FOOT WIND SPEEDS GRADUALLY SUBSIDING
BUT STILL REMAINING IN THE 15 TO 20 MPH RANGE WITH SOME HIGHER GUSTS.
20 FOOT DOWNSLOPING SOUTHWESTERLY WINDS WILL INCREASE AFTER MID TO
LATE MORNING TO AROUND 20 TO 30 MPH WITH HIGHER GUSTS AND MINIMUM
AFTERNOON HUMIDITIES FALLING TO NEAR 20 PERCENT. ALTHOUGH ONLY
MARGINAL FIRE WEATHER CONDITIONS ARE EXPECTED SATURDAY...THE STRONG
WINDS ALONE MAY JUSTIFY ISSUING A FIRE DANGER STATEMENT FOR ELEVATED
FIRE WEATHER CONDITIONS. ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS
ARE NOT EXPECTED SUNDAY THROUGH LATE NEXT WEEK AS EITHER THE MINIMUM
AFTERNOON RELATIVE HUMIDITIES REMAIN AT OR ABOVE 20 PERCENT OR THE 20
FOOT WIND SPEEDS REMAIN BELOW 15 TO 20 MPH.
SCHNEIDER
&&
.PRELIMINARY POINT TEMPS/POPS...
AMARILLO TX 45 71 42 66 32 / 20 0 0 0 0
BEAVER OK 46 74 38 61 27 / 5 0 0 5 0
BOISE CITY OK 42 69 34 62 28 / 5 0 0 5 0
BORGER TX 53 75 45 62 35 / 10 0 0 0 0
BOYS RANCH TX 46 71 41 66 31 / 20 0 0 5 0
CANYON TX 44 72 40 70 31 / 20 0 0 0 0
CLARENDON TX 50 74 46 68 35 / 20 0 0 0 0
DALHART TX 41 68 32 62 26 / 5 0 0 5 0
GUYMON OK 46 75 38 62 29 / 5 0 0 5 0
HEREFORD TX 43 71 40 68 30 / 20 0 0 0 0
LIPSCOMB TX 48 75 43 63 29 / 5 0 0 5 0
PAMPA TX 48 71 43 62 34 / 10 0 0 0 0
SHAMROCK TX 49 77 46 69 33 / 20 0 0 5 0
WELLINGTON TX 49 80 47 71 35 / 20 0 0 5 0
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
09/11
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
334 PM CST FRI NOV 15 2013
.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
334 PM CST FRI NOV 15 2013
RAIN MOVING IN SATURDAY AND POSSIBILITY OF STRONG THUNDERSTORMS LATE
SATURDAY NIGHT INTO SUNDAY MORNING ARE THE MAIN SHORT TERM CONCERNS.
WATER VAPOR IMAGERY THIS AFTERNOON SHOWING WEAK RIDGING ACROSS THE
UPPER MISSISSIPPI RIVER VALLEY REGION WHILE A DEEPENING TROUGH WAS
TAKING PLACE OVER THE WESTERN CONUS/INTERMOUNTAIN REGION. A WEAKER
EMBEDDED MID-LEVEL/SURFACE SHORTWAVE TROUGH WS NOTED MOVING EASTWARD
ACROSS THE DAKOTAS AND CENTRAL PLAINS. THIS WAS PRODUCING
SCATTERED/HIGH-BASED RAIN SHOWER ACTIVITY ACROSS A PORTION OF
SOUTHEAST ND/NORTHEAST SD. OTHERWISE...INCREASING SOUTHERLY FLOW
AHEAD OF THIS TROUGH AND MOSTLY SUNNY SKIES ACROSS THE UPPER
MISSISSIPPI RIVER VALLEY REGION WAS LEADING TO FAIRLY MILD AFTERNOON
TEMPERATURES IN THE UPPER 40S TO THE MIDDLE 50S ACROSS OUR AREA.
FOR TONIGHT...WILL BE WATCHING THAT TROUGH ACROSS THE
DAKOTAS/CENTRAL PLAINS MOVE SLOWLY EASTWARD INTO THE EASTERN
DAKOTAS/NEBRASKA BY SATURDAY MORNING. MODELS SHOWING INCREASING 285-
290K ISENTROPIC LIFT/MOISTURE TRANSPORT AHEAD OF THE WAVE FOR
INCREASING CLOUDS AND A SLIGHT CHANCE OF RAIN ACROSS PORTIONS OF
NORTHEAST IA/SOUTHEAST MN TOWARD DAYBREAK.
RAIN WILL RAPIDLY OVERSPREAD THE AREA DURING THE DAY SATURDAY AS THE
TROUGH/ASSOCIATED MOISTURE TRANSPORT MOVE SQUARELY INTO THE REGION.
NAM ALSO DEPICTING 0-3KM ML MUCAPE INCREASING INTO THE 500-700J/KG
RANGE BY AFTERNOON AS MID-LEVEL LAPSE RATES STEEPEN. THIS WILL LEAD
TO A CHANCE OF THUNDERSTORMS. MILDER AIR IN PLACE WILL PUSH
TEMPERATURES ONCE AGAIN INTO THE UPPER 40S TO THE MIDDLE 50S.
APPEARS THERE MAY BE A BIT OF A LULL IN THE RAIN ACTION SATURDAY
EVENING...THEN PICKING UP A AGAIN AFTER MIDNIGHT AS FAIRLY STRONG
SURFACE CYCLOGENESIS TAKES PLACE OVER MN. IN FACT...THE NAM IS
PRODUCING 0-3KM MUCAPE IN THE 1000-1500J/KG RANGE IN THE 09-12Z TIME
FRAME ACROSS PORTIONS OF NORTHEAST IA INTO FAR SOUTHWEST WI IN THE
WARM SECTOR JUST EAST OF THE SURFACE LOW. 0-3KM BULK SHEAR ALSO
PRETTY IMPRESSIVE IN THE 35-45KT RANGE. THIS COULD LEAD TO A FEW
LOCALLY STRONG-SEVERE THUNDERSTORMS WITH LARGE HAIL/DAMAGING WINDS.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
315 PM CST FRI NOV 15 2013
SHOWERS AND SCATTERED THUNDERSTORMS LOOK TO BE ONGOING THROUGH
SUNDAY AS THE LOW CONTINUES TO DEEPEN AND MOVE ACROSS THE AREA.
APPEARS ANY SEVERE THUNDERSTORM THREAT WOULD BE CONFINED TO EARLY
SUNDAY MORNING THEN WANE AS BETTER INSTABILITY/DYNAMIC SHIFT EAST OF
THE AREA. LOOK FOR HIGHS AGAIN IN THE UPPER 40S TO THE MIDDLE
50S...THEN SLOWLY FALLING THROUGH THE AFTERNOON AS COLD AIR
ADVECTION TAKES PLACE BEHIND THE DEPARTING LOW.
A LINGERING CHANCE OF RAIN...CHANGING TO SNOW WILL BE SEEN ACROSS
THE AREA SUNDAY NIGHT ON THE BACKSIDE OF THE DEEPENING LOW AS IT
MOVES NORTH ACROSS LAKE SUPERIOR INTO SOUTHERN ONTARIO. LITTLE IF
ANY SNOW ACCUMULATION IS EXPECTED...WITH PERHAPS A DUSTING AROUND
1/10 OF AN INCH ON GRASSY SURFACE POSSIBLE ALONG AND NORTH OF I-94.
OTHERWISE...LOOK FOR BLUSTERY NORTHWEST WINDS TO DRAW IN COLDER AIR
ACROSS THE AREA WITH OVERNIGHT LOWS DIVING INTO THE 20S.
COLD/BLUSTERY CYCLONIC FLOW WILL CONTINUE ACROSS THE AREA MONDAY
AROUND THE LOW AS IT MOVES TOWARD JAMES BAY. MUCH COLDER AIR WILL
FILTER INTO THE AREA ON BRISK NORTHWEST WINDS WITH HIGHS ONLY
EXPECTED TO TOP OFF IN THE 30S.
A RIDGE OF HIGH PRESSURE WILL THEN DRIFT EAST ACROSS THE REGION FROM
MONDAY NIGHT THROUGH WEDNESDAY FOR A QUIET PERIOD. PLAN ON HIGHS
TUESDAY IN THE MIDDLE 30S TO AROUND 40 AND IN THE UPPER 30S TO
MIDDLE 40S ON WEDNESDAY.
THE NEXT CHANCE OF PRECIPITATION COMES ALONG WEDNESDAY NIGHT THROUGH
THURSDAY AS BOTH THE GFS AND ECMWF SHOW A FAIRLY VIGOROUS MID-LEVEL
TROUGH SWINGING THROUGH THE DAKOTAS THROUGH THE UPPER MISSISSIPPI
RIVER VALLEY REGION. HIGHS ON THURSDAY ARE EXPECTED TO BE RIGHT
AROUND SEASONAL NORMS IN THE UPPER 30S TO THE MIDDLE 40S.
GFS AND ECMWF A BIT AT ODDS FOR THURSDAY NIGHT INTO FRIDAY. THE
ECMWF WANTS TO BUILD A SURFACE RIDGE INTO THE AREA WHILE THE GFS
SHOWS A DEEPENING MID-LEVEL TROUGH MOVING OUT OF THE CENTRAL CONUS
FOR ANOTHER SHOT OF PRECIPITATION. WILL STICK WITH A MODEL CONSENSUS
FOR NOW WHICH YIELDS A 20-30 PERCENT CHANCE OF RAIN/SNOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1124 AM CST FRI NOV 15 2013
SHORT WAVE TROUGH CURRENTLY OVER THE INTERMOUNTAIN WEST WILL MAKE
RAPID PROGRESS TOWARD THE REGION TONIGHT AND SATURDAY. THE LOW LEVEL
JET IS EXPECTED TO INCREASE OVERNIGHT AHEAD OF THIS SYSTEM TO THE
POINT THAT LOW LEVEL WIND SHEAR BECOMES A POSSIBILITY AT BOTH TAF
SITES. THE 15.12Z NAM AND 15.15Z RAP BOTH SHOW THE WINDS BETWEEN
1500 AND 2000 FEET INCREASING TO BETWEEN 40 AND 45 KNOTS AND HAVE
CONTINUED THE INCLUSION OF THE WIND SHEAR. THE LOW LEVEL JET WILL
RAPIDLY BRING THE MOISTURE BACK INTO THE AREA AND THIS LOOKS TO FORM
MVFR CEILINGS OVERNIGHT. THE FORCING FROM THE SHORT WAVE TROUGH WILL
START TO INCREASE SATURDAY MORNING ALONG WITH SOME WEAK DIVERGENCE
ALOFT IN THE LEFT EXIT REGION OF THE 300 MB JET. THIS SHOULD BE
ENOUGH TO GENERATE SOME LIGHT RAIN AND HAVE INTRODUCED THIS BY MID
MORNING. AS THE MOISTURE AND RAIN CONTINUES...EXPECT TO SEE THE
CEILINGS CONTINUE TO GO DOWN WITH THE POSSIBILITY OF IFR CONDITIONS
AT KRST DURING THE AFTERNOON. NOT SURE IF THE RAIN WILL BECOME HEAVY
ENOUGH TO PRODUCE ANY VISIBILITY RESTRICTIONS AT THIS POINT...SO
HAVE NOT INCLUDED ANY AT THIS TIME.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1125 AM CST FRI NOV 15 2013
.SHORT TERM...(TODAY THROUGH TONIGHT)
305 AM CST FRI NOV 15 2013
QUIET END TO THE WORK WEEK WITH MOSTLY SUNNY SKIES AND DRY
CONDITIONS EXPECTED. SOUTHWEST TO SOUTH WINDS WILL HELP TEMPERATURES
SNIFF THE 50 DEGREE MARK...ABOUT 5 DEGREES ABOVE THE MID NOV
NORMALS.
SOME PATCHY FOG OUT THERE EARLY THIS MORNING...PER LATEST
OBSERVATIONS. DON/T ANTICIPATE WIDESPREAD FOG...BUT WITH LIGHT
SFC/NEAR SFC WINDS...WILL HAVE TO MONITOR OBS/CONDITIONS THROUGH
DAYBREAK.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
305 AM CST FRI NOV 15 2013
UPPER LEVEL SHORTWAVE TROUGH SLATED TO SPIN EAST OUT OF THE SOUTHERN
ROCKIES...SWINGING THROUGH THE UPPER MISSISSIPPI RIVER ON SAT. GOOD
MODEL AGREEMENT BETWEEN THE NAM/GFS/EC ON THIS. A SHOT OF LOW LEVEL
WARM AIR ADVECTION ACCOMPANIES THE SHORTWAVE...WITH A BIT OF QG
CONVERGENCE...MOSTLY IN THE 850-700 MB LAYER. GOOD PUNCH OF LOW
LEVEL MOISTURE...WITH A 50 KT LOW LEVEL JET NOSING NORTHEAST ACROSS
THE FORECAST AREA. NAM EVEN HINTS AT SOME INSTABILITY...WITH ABOUT
200-400 J/KG OF MUCAPE FOR THE AFTERNOON/EVENING. SHOWERS SHOULD
SPARK IN RESPONSE TO THE FORCING/ENOUGH SATURATION...AND COULD SEE A
FEW THUNDERSTORMS. SOME DIFFERENCES IN WHERE THE HIGHER PCPN THREAT
WILL LIE VIA THE GFS/NAM...BUT BOTH AGREE COVERAGE SHOULD INCREASE
DURING THE AFTERNOON SAT...WITH THAT AREA MOVING NORTHEAST DURING
THE EVENING.
DEEPER/STRONGER TROUGH WILL DROP OUT OF THE PAC NW...DRIVE ACROSS
THE PLAINS ON SUNDAY...THEN MOVE OVER THE EASTERN GREAT LAKES BY
SUNDAY NIGHT. THE SYSTEM/S SFC LOW WILL STRENGTHEN AS IT MOVES OVER
SOUTHERN WI BY 18Z SUN...CONTINUING ITS NORTHEAST TRACK INTO CANADA
LATE SUN NIGHT. QG CONVERGENCE MUCH STRONGER WITH THIS TROUGH THAN
WITH THE SATURDAY SHORTWAVE...ESPECIALLY IN THE 700-300 MB LAYER.
GOOD AMOUNT OF LOW LEVEL WARM AIR ADVECTION...AND SOME HELP FROM THE
LEFT EXIT REGION OF THE 300 MB JET. EXPECT ANOTHER ROUND OF
SHOWERS...AND PROBABLY A FEW THUNDERSTORMS...AS THIS SYSTEM MOVES
THROUGH. THE NAM IS A BIT FASTER AND FARTHER NORTHWEST IN ITS
MOVEMENT...ACROSS THE FORECAST AREA BY 12Z SUN. THE GFS/EC HOLDS OFF
UNTIL CLOSER TO 18Z AND TAKE A MORE SOUTHERLY ROUTE. LEANING TOWARD
THE GFS/EC. TEMPERATURES LOOK TO WARM TO POSE MUCH OF A SNOW
THREAT.
ALL IN ALL...A WET WEEKEND FOR MUCH OF THE REGION.
HIGH PRESSURE SLATED TO BUILD IN MONDAY NIGHT/TUE...WITH THE UPPER
LEVEL FLOW TAKING ON A MORE ZONAL LOOK THROUGH THU. THE EC FAVORS A
DRY FORECAST THROUGH THU. THE GFS...ON THE OTHER HAND...WOULD BRING
A BIT OF UPPER LEVEL ENERGY/LOW LEVEL WARM AIR ADVECTION ACROSS THE
PLAINS AND OVER THE FORECAST AREA. THIS WOULD RESULT IN SOME PCPN
CHANCES FOR TUE NIGHT/WED.
THE GFS CONTINUES MORE ACTIVE IN THE ZONAL FLOW COMPARED TO THE
EC...SLIDING ANOTHER SHORTWAVE TROUGH/SFC FRONT ACROSS THE UPPER
MISSISSIPPI RIVER VALLEY ON THU. A SWATH OF PCPN RESULTS VIA THE
GFS. THE EC HAS THE MAIN UPPER LEVEL SHORTWAVE...TRACKING ACROSS
SOUTHERN CANADA...BUT NOT THE OTHER PIECES OF ENERGY SPINNING
EASTWARD ACROSS THE PLAINS. IT DOES HAVE THE SFC FRONT...BUT WITH
OUT THE UPPER LEVEL SUPPORT...DOESN/T PRODUCE MUCH/IF ANY QPF ALONG
IT UNTIL POST THE BOUNDARY. EVEN THEN...ITS RELATIVELY LIGHT. WILL
LEAN ON THE CONSENSUS SOLUTION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1124 AM CST FRI NOV 15 2013
SHORT WAVE TROUGH CURRENTLY OVER THE INTERMOUNTAIN WEST WILL MAKE
RAPID PROGRESS TOWARD THE REGION TONIGHT AND SATURDAY. THE LOW
LEVEL JET IS EXPECTED TO INCREASE OVERNIGHT AHEAD OF THIS SYSTEM
TO THE POINT THAT LOW LEVEL WIND SHEAR BECOMES A POSSIBILITY AT
BOTH TAF SITES. THE 15.12Z NAM AND 15.15Z RAP BOTH SHOW THE WINDS
BETWEEN 1500 AND 2000 FEET INCREASING TO BETWEEN 40 AND 45 KNOTS
AND HAVE CONTINUED THE INCLUSION OF THE WIND SHEAR. THE LOW LEVEL
JET WILL RAPIDLY BRING THE MOISTURE BACK INTO THE AREA AND THIS
LOOKS TO FORM MVFR CEILINGS OVERNIGHT. THE FORCING FROM THE SHORT
WAVE TROUGH WILL START TO INCREASE SATURDAY MORNING ALONG WITH
SOME WEAK DIVERGENCE ALOFT IN THE LEFT EXIT REGION OF THE 300 MB
JET. THIS SHOULD BE ENOUGH TO GENERATE SOME LIGHT RAIN AND HAVE
INTRODUCED THIS BY MID MORNING. AS THE MOISTURE AND RAIN
CONTINUES...EXPECT TO SEE THE CEILINGS CONTINUE TO GO DOWN WITH
THE POSSIBILITY OF IFR CONDITIONS AT KRST DURING THE AFTERNOON.
NOT SURE IF THE RAIN WILL BECOME HEAVY ENOUGH TO PRODUCE ANY
VISIBILITY RESTRICTIONS AT THIS POINT...SO HAVE NOT INCLUDED ANY
AT THIS TIME.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1138 PM CST THU NOV 14 2013
.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 322 PM CST THU NOV 14 2013
CONCERNS THROUGH THE SHORT TERM PERIOD INCLUDE RAIN CHANCES INTO
THIS EVENING AND AREAS OF FOG OVERNIGHT.
WATER VAPOR COUPLED WITH RAP 500MB ANALYSIS SHOWING A MID-LEVEL
TROUGH ROTATING EAST OUT OF THE DAKOTAS TOWARD THE UPPER MISSISSIPPI
RIVER VALLEY REGION. RAP SHOWING RIGHT ENTRANCE REGION OF 300MB JET
COUPLED WITH FAIRLY STRONG 700-500MB FRONTOGENESIS ACROSS OUR REGION
AHEAD OF THE APPROACHING MID-LEVEL WAVE. RESULT...PER REGIONAL RADAR
MOSAIC AND SURFACE OBSERVATION WAS A NARROW BAND OF LIGHT RAIN
EXTENDING FROM NORTHEAST WI THROUGH WINONA AND LA CROSSE...TO
PORTIONS OF SOUTHEAST MN/NORTH CENTRAL IA. CLOUDS AND LIGHT
SOUTHERLY SURFACE FLOW KEEPING TEMPERATURES IN CHECK IN THE UPPER
30S TO THE MID 40S.
WILL BE WATCHING THE MID-LEVEL TROUGH TO SLIP EAST ACROSS THE AREA
THIS EVENING/OVERNIGHT WITH BETTER FRONTOGENESIS EXITING EAST EARLY
ON IN THE EVENING. THIS SHOULD BRING AND END TO ANY LIGHT RAIN
ACTIVITY. A WEAK SURFACE TO MID-LEVEL RIDGE OF HIGH PRESSURE BUILDS
IN TOWARD MORNING. AS A RESULT...EXPECTING A GENERAL CLEARING TREND
LATER THIS EVENING THROUGH THE REST OF THE NIGHT. CONCERN THEN
BECOMES FOG POTENTIAL WITH RADIATIONAL COOLING AND RELATIVELY MOIST
LOWER BOUNDARY LAYER GIVEN TODAY/S LIGHT RAINFALL. WENT WITH AREAS
OF FOG IN THE MAIN RIVER STEMS AND PATCH FOG ELSEWHERE. WILL HAVE TO
WATCH THIS CLOSE OVERNIGHT AS ANY FURTHER CLEARING/RADIATIONAL
COOLING COULD LEAD TO POCKETS OF DENSE FOG IN THE MORNING AROUND
COMMUTE TIME.
FOR FRIDAY...MODEL SOUNDING SHOWING THE INVERSION BREAKING AROUND
NOON WITH SOUTHERLY FLOW KICKING IN ON THE BACKSIDE OF THE DEPART
HIGH AND IN ADVANCE OF APPROACHING TROUGH OVER THE HIGH PLAINS.
UNDER PARTLY CLOUDY SKIES...LOOK FOR TEMPERATURES TO MODERATE INTO
SLIGHTLY ABOVE SEASONAL NORMAL TERRITORY AS READING REACH INTO THE
UPPER 40S TO THE LOWER 50S.
SOUTHERLY SURFACE FLOW CONTINUES INTO FRIDAY NIGHT AHEAD OF THE
APPROACHING TROUGH WITH INCREASING 290K ISENTROPIC LIFT/850MB
MOISTURE TRANSPORT. THIS STRONGEST OF THIS FORCING WILL REMAIN JUST
TO OUR WEST THROUGH 12Z SATURDAY MORNING FOR BEST CHANCE OF COLUMN
SATURATION/RAINFALL. WENT WITH A SMALL/20 PERCENT CHANCE OF RAIN
WEST OF A CHARLES CITY TO ROCHESTER LINE AFTER 3 AM SATURDAY.
SOUTHERLY FLOW/INCREASING CLOUDS WILL KEEP TEMPERATURES UP IN THE
MID-UPPER 30S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 330 PM CST THU NOV 14 2013
LOOK FOR A RAPID EXPANSION OF RAIN ACROSS THE AREA SATURDAY MORNING
AS BROADSCALE SOUTHERLY FLOW/LIFT/MOISTURE TRANSPORT MOVE SQUARELY
INTO THE REGION. FAIRLY MILD CONDITIONS WITH HIGHS IN THE UPPER 40S
TO MIDDLE 50S CAN BE EXPECTED SATURDAY. MILD/MOIST CONDITIONS ALONG
WITH DYNAMICS/MID-LEVEL STEEPENING LAPSE RATES WILL ALSO PRODUCE A
SMALL CHANCE OF THUNDER BY AFTERNOON.
LOOK FOR THE LIKELIHOOD OF RAIN AND POCKETS OF THUNDER TO CONTINUE
ACROSS THE AREA SATURDAY NIGHT INTO SUNDAY AS STRONGER SURFACE
CYCLOGENESIS TAKES PLACE AND MOVES NORTHEAST ACROSS THE UPPER
MISSISSIPPI RIVER VALLEY REGION. STILL SOME UNCERTAINTY BETWEEN THE
MODELS ON INTENSITY AND EXACT TRACK OF THE LOW...BUT ALL POINT
TOWARD OUR AREA BEING IN THE WARM SECTOR OF THE LOW...ESPECIALLY THE
ECMWF. THE NAM PRODUCES 1200-1500J/KG OF 0-3KM ML MUCAPE SUNDAY
ACROSS PORTIONS OF FAR SOUTHWEST WI IN THE WARM SECTOR WITH AMPLE
BULK SHEAR. GIVEN THIS SIGNAL AND SYSTEM DYNAMICS..WILL HAVE TO
WATCH FOR A SEVERE THUNDERSTORM POTENTIAL ACROSS THAT AREA.
OTHERWISE...MODEL CONSENSUS PRODUCES HIGH TEMPERATURES SUNDAY IN THE
UPPER 40S TO THE MIDDLE 50S.
GFS AND ECMWF CONTINUE AT ODDS ON MOVEMENT/INTENSITY OF THE SURFACE
LOW THROUGH SUNDAY NIGHT...WITH THE ECMWF REMAINING SLOWER/MORE
INTENSE AS IT LIFTS INTO UPPER MICHIGAN. THIS WOULD PRODUCE
DEFORMATION RAIN CHANGING TO POSSIBLY MEASURABLE SNOW FOR MUCH OF
THE AREA. THE GFS ON THE OTHERHAND IS MORE OPEN/PROGRESSIVE WITH THE
LOW...LIFTING THE PRECIPITATION OUT OF THE AREA BY MIDNIGHT SUNDAY
NIGHT. WILL GO WITH A MODEL CONSENSUS FOR NOW UNTIL THERE IS BETTER
AGREEMENT...WHICH PRODUCES A 30-40 PERCENT CHANCE OF RAIN
EARLY...CHANGING OVER TO SNOW.
COLD AIR ADVECTION ON BLUSTERY NORTHWEST WINDS EXPECTED ON MONDAY
BEHIND THE DEPARTING LOW. A FEW SNOW SHOWERS WILL ALSO BE POSSIBLE
ACROSS NORTH CENTRAL WI IN THIS COLD CYCLONIC FLOW. LOOK FOR HIGHS
ONLY IN THE 30S.
A FAIRLY STRONG RIDGE OF HIGH PRESSURE MOVES ACROSS THE AREA MONDAY
NIGHT THROUGH WEDNESDAY FOR A QUIET PERIOD. TEMPERATURES WILL REMAIN
CHILLY THOUGHT WITH HIGHS IN THE 30S AND LOWS IN THE TEENS AND LOWER
20S.
NEXT CHANCE OF PRECIPITATION FOR THE AREA LOOKS TO BE ON THURSDAY AS
WARM AIR ADVECTION AND WEAK MOISTURE TRANSPORT TAKE PLACE AHEAD OF A
TROUGH OF LOW PRESSURE MOVING OUT OF THE NORTHERN PLAINS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1138 PM CST THU NOV 14 2013
FOG POTENTIAL THIS MORNING REMAINS THE MAIN CONCERN FOR THE
AVIATION FORECAST. DEWPOINT DEPRESSIONS HAVE FALLEN CONSIDERABLY
AT RST...DOWN TO 3F AS OF 05Z...DESPITE THE PRESENCE OF A 5-10 KT
WESTERLY BREEZE. AT LSE...A SOUTH WIND HAS KEPT DEWPOINT
DEPRESSIONS HIGH...AT 11F AS OF 05Z. WITH CLEAR SKIES AND THE
PRESSURE GRADIENT GRADUALLY RELAXING...CURRENT CONDITIONS WOULD
THEREFORE MAKE RST MORE LIKELY TO SEE SOME FOG DEVELOPMENT.
HOWEVER...THAT 5 TO 10 KT BREEZE DOES NOT LOOK TO DIMINISH MUCH
THIS MORNING. HAVE KEPT THE POTENTIAL FOR VISIBILITIES TO DROP TO
IFR FOR 11-15Z. AT LSE...THE HIGHER DEWPOINT DEPRESSION IS
CONCERNING...BUT WINDS WILL BE LIGHTER AND THUS THE TEMP STANDS A
BETTER CHANCE OF HITTING THE DEWPOINT. HERE TOO HAVE KEPT THE
POTENTIAL FOR IFR VISIBILITIES FOR 11-15Z. ONLY REAL ADJUSTMENT
WAS TO DELAY ANY VISIBILITY REDUCTION TIL 10Z AT THE EARLIEST.
AFTER 15Z...VFR CONDITIONS WILL PREVAIL AS A DRY AIRMASS IS IN
PLACE IN THE LOWER TO MID LEVELS OF THE ATMOSPHERE.
ONE ISSUE TOWARDS 06Z FRIDAY NIGHT IS LOW LEVEL WIND SHEAR...
POSSIBLY AT BOTH TAF SITES. THE PRESSURE GRADIENT LOOKS TO TIGHTEN
UP...CAUSING WINDS TO INCREASE...ESPECIALLY ABOVE THE SURFACE.
WILL LET THE NEXT TAF FORECAST ADDRESS THE LOW LEVEL WIND SHEAR
MORE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1051 PM CST THU NOV 14 2013
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.UPDATE...
ISSUED AT 756 PM CST THU NOV 14 2013
NARROW BAND OF LIGHT RAIN SHOULD EXIT THE SE PART OF GRB CWA BETWEEN
03Z-04Z. ALTHOUGH CLOUDS WILL MOVE THROUGH PARTS OF NORTHERN WI
TONIGHT...MUCH OF C/NE/EC WI SHOULD BECOME PARTLY CLOUDY. PARTIAL
CLEARING AND LIGHT WINDS SHOULD ALLOW FOG TO DEVELOP...SO HAVE
EXPANDED THE COVERAGE OF FOG OVER MOST OF THE CWA LATER TONIGHT.
THINK THAT BOUNDARY LAYER WINDS AROUND 15 KTS SHOULD KEEP THE FOG
FROM BECOMING DENSE IN MOST PLACES. HAVE LOWERED MIN TEMPS OVER
MOST OF THE FORECAST AREA.
&&
.SHORT TERM...TONIGHT AND FRIDAY
ISSUED AT 248 PM CST THU NOV 14 2013
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A SURFACE
TROUGH/WARM FRONT MOVING EAST ACROSS THE NORTHERN MISSISSIPPI
VALLEY EARLY THIS AFTERNOON. ELEVATED FRONTAL ZONE/RIGHT REAR QUAD
OF JET STREAK IS PRODUCING A BAND OF SPRINKLES OR VERY LIGHT RAIN
FROM NORTHWEST IOWA TO NORTHEAST WISCONSIN. A FEW OBS OVER SW
WISCONSIN ARE SHOWING THE RAIN REACHING THE GROUND...AND THINK THE
SAME CAN BE SAID OVER CENTRAL AND NORTHEAST WISCONSIN. THIS BAND
SHOULD CONTINUE TO MOVE SOUTHEAST OVER THE REST OF THE AFTERNOON
AND REACH THE FOX VALLEY BEFORE 00Z. CLEARING SKIES ARE WORKING
INTO WESTERN WISCONSIN BEHIND THE FRONT WITH TEMPERATURES RISING
INTO THE MIDDLE 50S. THEN ANOTHER AREA OF STRATUS IS WORKING
SOUTHEAST OVER NORTH DAKOTA AND NORTHERN MINNESOTA. FORECAST
CONCERNS INCLUDE CLOUD AND LIGHT PRECIP TRENDS...FOLLOWED BY
TEMPS.
TONIGHT...THE SHORTWAVE TROUGH MOVING INTO THE WESTERN GREAT LAKES
WILL MOVE ACROSS THE LAKE SUPERIOR REGION TONIGHT. IT WILL PUSH A
ELEVATED FRONTAL ZONE ACROSS NORTHEAST WISCONSIN EARLY THIS
EVENING BEFORE EXITING BY MIDNIGHT. HAVE KEPT A CHANCE OF SPRINKLES
GOING INTO THE EVENING TO ACCOUNT FOR UPPER DIVERGENCE AND WEAK
CONVERGENCE ALONG THE FRONTAL ZONE. ONCE MID AND UPPER CLOUDS
DEPART EAST-CENTRAL WISCONSIN LATE IN THE EVENING...MODELS SHOW
MID-LEVEL DRYING TAKING PLACE ACROSS THE REGION. THINK THIS WILL
LEAD TO CLEARING ACROSS ALL BUT FAR N-C WISCONSIN. AREA OF CLOUDS
ACROSS NORTHERN MINNESOTA/NORTH DAKOTA LOOK TO AT LEAST GRAZE
NORTHERN WISCONSIN...SO HAVE KEPT PARTLY TO MOSTLY CLOUDY CONDITIONS
GOING THERE THROUGH THE NIGHT. STATISTICAL GUIDANCE SHOWS LOW
STRATUS OR FOG DEVELOPING WHERE SKIES CLEAR OUT...AND WOULD BE
POSSIBLE IF DEWPOINTS CAN RISE INTO THE LOWER OR MIDDLE 30S..LIKE
THEY DID OVER MINNESOTA. THINK THIS WILL OCCUR ACROSS OUR AREA LATE
THIS AFTERNOON AND EVENING AS THE SURFACE TROUGH MOVES THROUGH...BUT THERE
MAY BE TOO MUCH WIND FOR FOG TO DEVELOP...SO LOW STRATUS IS A BETTER
OPTION. AFTER PARTIALLY CLEARING SKIES THIS EVENING...WILL INCREASE
CLOUDS LATE TONIGHT WITH ANTICIPATION OF STRATUS DEVELOPING. THE
SREF SUPPORTS THIS IDEA. CONTINUED TO GO WITH THE WARMER SIDE OF
TEMPS TONIGHT...WHICH PLACES THEM IN THE UPPER 20S TO MID 30S.
FRIDAY...WEAK ARCTIC FRONT WILL MOVE ACROSS WESTERN LAKE SUPERIOR
AND THE UPPER PENINSULA DURING THE MORNING...BUT LOSE DEFINITION
ACROSS NORTHERN WISCONSIN. RESIDUAL MOISTURE ALONG THE FRONT WILL
LIKELY LEAD TO SCT OR BKN CLOUD COVER ACROSS THE NORTH. THESE
CLOUDS SHOULD LIFT OFF TO THE NORTHEAST DURING THE AFTERNOON.
ELSEWHERE...ANY SHALLOW FOG/STRATUS SHOULD DISSIPATE EARLY...WHICH
WILL LEAVE A MOSTLY SUNNY OR PARTLY CLOUDY CONDITIONS FOR MUCH OF
THE DAY. HIGHS RANGING THROUGH THE 40S.
.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY
ISSUED AT 248 PM CST THU NOV 14 2013
PLENTY OF CONCERNS IN THE LONG TERM PORTION OF THE FORECAST...MAINLY
CENTERED AROUND A SECONDARY LOW PROGGED TO MOVE ACROSS THE REGION
LATE IN THE WEEKEND. THE ECMWF AND GEM ARE SLOWER THAN THE GFS IN
EJECTING A STRONG SHORTWAVE TROUGH/SURFACE LOW ACROSS THE PLAINS AND
GREAT LAKES. LOOKING AT HPC DISCUSSIONS...THEY FAVOR USING THE
ECMWF ENSEMBLE MEAN...WHICH HAS MORE SUPPORT FROM OTHER OPERATIONAL
MODELS THAN THE GFS/GFS ENSEMBLE MEAN. NOT CONVINCED SLOWER IS
BETTER IN THIS INSTANCE SINCE THERE IS AN ABSENCE OF BLOCKING ACROSS
THE CONTINENT AND THERE IS A 150KT RELATIVELY ZONAL JET UPSTREAM OF
THE TROUGH. THIS WOULD ARGUE FOR A MORE PROGRESSIVE PATTERN. SO
WITH CONFLICTING SIGNALS...GUESS ITS BEST TO GO WITH AN ECMWF/GFS
BLEND TO MITIGATE THESE DIFFERENCES.
FRIDAY NIGHT THROUGH SUNDAY...MID AND HIGH CLOUDS WILL BE ON THE
INCREASE FRIDAY NIGHT AS LEAD SHORTWAVE ENERGY EJECTS INTO THE
CENTRAL PLAINS. WITH INCREASING CLOUDS AND A TIGHTENING PRESSURE
GRADIENT...WILL SIDE ON THE WARM SIDE OF GUIDANCE. THE LEAD
SHORTWAVE TROUGH WILL MOVE NORTHEAST AND ACROSS WISCONSIN DURING THE
AFTERNOON. AHEAD OF THE TROUGH...A 50+KT LLJ WILL DEVELOP AND
TRANSPORT MOISTURE ACROSS THE STATE. WITH DECENT -DIVQ IN THE MID
AND UPPER LEVELS...AND STRONG MOISTURE ADVECTION IN THE LOW
LEVELS...RAIN IS A SOLID BET LATE SATURDAY MORNING AND THROUGH THE
AFTERNOON. WILL INCREASE POPS. THE MAIN AREA OF RAIN WILL BE
EXITING TO THE NORTHEAST OVER THE COURSE OF SATURDAY EVENING AS THE
REGION GETS TEMPORARILY DRY SLOTTED. PLENTY OF LOW LEVEL MOISTURE
WILL BE LEFT THOUGH...AND WITH WEAK WARM ADVECTION
CONTINUING...SHOULD SEE PLENTY OF CLOUDY COVER AND MAYBE PATCHY
DRIZZLE/FOG LEFT OVER. PREVIOUS SHIFT ALREADY HAD THIS COVERED PRETTY
WELL. THE SECONDARY LOW WILL THEN ORGANIZE ACROSS THE PLAINS AND
LIFT NE ACROSS THE SOUTHEAST HALF OF WISCONSIN ON SUNDAY. SHOULD
SEE ANOTHER ROUND OF PRECIP ARRIVE WITH THIS LOW...HEAVIEST ACROSS
THE SOUTHEAST HALF OF THE FORECAST AREA. PRECIP TYPE LOOKS TO
REMAIN ALL LIQUID. NO SIGNIFICANT CHANGES TO TEMPS.
REST OF THE FORECAST...THE SURFACE LOW WILL EXIT SUNDAY NIGHT AND A
CHANGE OVER TO SNOW IS ANTICIPATED AS COLDER AIR RUSHES IN BEHIND
THE CYCLONE. CANNOT GET EXCITED ABOUT ACCUMS THOUGH...UNTIL MORE
CONSENSUS DEVELOPS IN THE DETAILS. WINDY CONDITIONS WILL ACCOMPANY
THE COLD ADVECTION SUNDAY NIGHT INTO MONDAY. IF THE SLOWER SOLUTION
WORKS OUT...WIND HEADLINES WILL BE POSSIBLE. CLOUDY AND COLD ON
MONDAY WITH HIGHS RETURNING TO THE 20S AND 30S. THEN A SLOW WARMING
TREND ENSUES MID-WEEK ONWARD.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1046 PM CST THU NOV 14 2013
LIGHT RAIN HAS ENDED OVER EC WI...AND CLEARING WILL OCCUR THERE
WITHIN THE NEXT FEW HOURS. SCT-BKN STRATOCUMULUS/ALTOCUMULUS WILL
MOVE THROUGH NORTHERN WI OVERNIGHT. PARTLY CLOUDY SKIES AND LIGHT
WINDS SHOULD ALLOW FOG TO DEVELOP OVER MOST OF THE FORECAST AREA
OVERNIGHT INTO FRIDAY MORNING. HAVE CONTINUED THE MENTION OF FOG
IN THE TAFS...WITH TEMPO GROUPS FOR LIFR/IFR CONDITIONS. THE
FOG WILL MIX OUT BY MID-MORNING...WITH MAINLY SCT-BKN HIGH CLOUDS
FOR THE AFTERNOON/EVENING.
&&
.MARINE...
ISSUED AT 248 PM CST THU NOV 14 2013
WEST TO NORTHWEST GALES ARE EXPECTED LATE SUNDAY NIGHT INTO MONDAY
NIGHT AS A STRONG AREA OF LOW PRESSURE MOVES AWAY FROM THE AREA.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE.........KIECKBUSCH
SHORT TERM.....MPC
LONG TERM......MPC
AVIATION.......KIECKBUSCH
MARINE.........MPC
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1000 PM MST SAT NOV 16 2013
.UPDATE...
ISSUED AT 950 PM MST SAT NOV 16 2013
SNOW LEVELS WERE AROUND 6.5KFT NORTH TO 8.5KFT SOUTH WITH
CONVECTION PULLING IT LOWER LOCALLY. A QUICK REVIEW OF SNOTEL
SITES TOTAL STORM AMOUNTS: IN EASTERN UTAH MTNS 1-4 INCHES. IN
WESTERN COLORADO IN THE NORTHERN MTNS 6-12 INCHES WITH HIGHER
AMOUNTS NEAR THE WYOMING BORDER AND NORTH SIDE OF THE FLATTOPS.
CENTRAL MTNS 5-10 INCHES WITH 17 INCHES AT SCHOFIELD PASS.
SOUTHERN MTNS 6-15 INCHES FAVORING THE NW SAN JUANS BUT MOLAS PASS
HAS GOTTEN AROUND 15 INCHES. THE SNOW LULL EARLY SATURDAY MORNING
IS EVIDENT IN MOST GRAPHS.
THE 120KT JET NOSE IS ORIENTED FROM POCATELLO TO PAGOSA SPRINGS
THIS EVENING AND WILL LIFT NE OUT OF THE FORECAST AREA BY
SUNRISE. THE UPPER LEVEL SUPPORT FOR THIS STORM IS SHIFTING EAST
OF THE CONTINENTAL DIVIDE. AFTER MIDNIGHT THE FORECAST AREA WILL
GENERALLY BE IN THE COLD ADVECTIVE NW FLOW THAT CAN PRODUCE GOOD
SHALLOW CONVECTIVE SNOWFALL ALONG NW FACING SLOPES. THE
ELKHEADS/PARK/GORE/FLATTOPS/ELKS/WEST ELKS LOOK TO BE FAVORED WITH
SNOWFALL OVERNIGHT WITH THE NEW NAM12 PRODUCING UP TO 6 NEW
INCHES. THE SAN JUANS ARE PROGGED TO RECEIVE LESS AND THE
UNCOMPAHGRE GORGE DOES NOT LOOK FAVORED WITH TEMPERATURES TOO MILD
AND THE MTN TOP WINDS FROM THE WNW WHICH IS NOT FAVORABLE.
SNOW ACCUMULATIONS SUNDAY MORNING LOOK TO BE LIGHT...SO MOST
HIGHLIGHTS WILL LIKELY END WITH SUNRISE. THE NW COLORADO MTNS
HIGHLIGHTS MAY STAY IN EFFECT UNTIL NOON WITH LIGHT SNOW FALLING
IN THE MORNING HOURS.
THE BROAD TROUGH REMAINS OVER THE WEST WITH SOME CHANCE OF MTN
SNOWS TUESDAY AND ESPECIALLY THURSDAY AND PERHAPS INTO NEXT
WEEKEND IF THE GFS IS FOLLOWED.
&&
UPDATE ISSUED AT 525 PM MST SAT NOV 16 2013
JET AXIS WILL TRANSLATE ACROSS NWRN COLORADO TONIGHT...EXPECT THIS
TO ENHANCE OROGRAPHIC SNOW THIS EVENING. EXPECT ONE MORE BURST OF
HEAVY SNOW RATES BEFORE THE FLOW ALOFT BECOMES ANTICYCLONIC AND
THE MOISTURE ERODES FROM THE WEST (ALREADY UNDERWAY). RAP AND HRRR
MODELS SEEM TO INDICATE THAT AREAS EAST OF CRAIG WILL GET DECENT
SNOW ACCUMULATIONS THIS EVENING. ELECTED TO HOIST WINTER WEATHER ADVISORY
FOR THE STEAMBOAT SPRINGS VICINITY. CONSIDERED CRAIG/MEEKER AND
GLENWOOD SPRINGS/EAGLE AREAS AS WELL...BUT APPEARS THAT SNOWFALL
WILL NOT REACH THE 2-4 INCH RANGE FOR THESE LOCATIONS. THE I-70
CORRIDOR IS LESS LIKELY TO EXCEED 1 INCH...BUT SPOTTY ACCUMULATIONS
ON GRASSY SURFACES MAY OCCUR. THE WIND ADVISORY DID NOT PAN OUT
IN THE MOIST POST FRONTAL ENVIRONMENT AND HAS BEEN CANCELLED 1
HOUR EARLY.
&&
.SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 248 PM MST SAT NOV 16 2013
WINTER WEATHER PRODUCTS WILL CONTINUE FOR MOST OF THE WRN CO
MOUNTAINS. ONE SHORTWAVE TROUGH OVER NORTHERN AND CENTRAL CO THIS
AFTERNOON WILL MOVE EAST AND PRODUCE SNOWFALL IN THE MOUNTAINS AND
MIX OF RAIN AND SNOW IN THE HIGHER VALLEYS THROUGH THIS EVENING. A
BRIEF LULL SHOULD OCCUR IN THE LATE EVENING...THEN ANOTHER WEAKER
SHORTWAVE WILL MOVE OVER THE NORTHERN HALF OF CO FROM JUST BEFORE
MIDNIGHT TO JUST BEFORE SUNRISE. SKIES SHOULD CLEAR FROM WEST TO
EAST SUNDAY MORNING. TEMPS...MOISTURE AND COLD ADVECTION ARE ALL
GOOD FOR DECENT SNOW ACCUMULATION. THE 700 MB TEMPS DROPPING TO -6
AND -7 DEGREE C TONIGHT WILL BRING SNOWFALL DOWN TO VALLEY BOTTOMS
LATE. STEADY WNW ALOFT WILL PROVIDE GOOD OROGRAPHIC SUPPORT FOR
SNOWFALL ON WEST AND NORTHWEST FACING SLOPES.
SUNDAY AND SUNDAY NIGHT SHOULD SEE DRAMATICALLY CLEARING SKIES.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 248 PM MST SAT NOV 16 2013
MONDAY WILL BE CALM AND UNEVENTFUL AS LIGHT WESTERLY WINDS FROM
WEAK RIDGING TAKE OVER THE WEATHER PATTERN. TEMPERATURES WILL
ADVANCE BACK UP TO NEAR NORMAL MONDAY AND TUESDAY BEFORE A WEAK
WAVE SWINGS BY THE NORTHERN COUNTIES THURSDAY NIGHT...PRODUCING
CLOUDY CONDITIONS AND A TRACE OF PRECIPITATION AT BEST ALONG THE
CO/WY BORDER.
THE 12Z MODELS MOVE IN A WEAK UPPER LEVEL TROUGH WHICH BRINGS A
CHANCE OF PRECIPITATION TO THE HIGHER ELEVATIONS WEDNESDAY
AFTERNOON.
THE BIG STORY IN THE LONG RANGE WILL BE A SYSTEM APPROACHING LATE
WEEK...POTENTIALLY EARLY THURSDAY OR POTENTIALLY FRIDAY DEPENDING
ON WHICH WX MODEL YOU ARE ANALYZING. CONFIDENCE IS LOW AS THE
MODELS DIVERGE ON TIMING AND SPATIAL COVERAGE OF THIS LATE WEEK
FEATURE. NONETHELESS...THE LAST FEW MODEL RUNS HAVE BEEN
SIGNALING A STRONG STORM THROUGHOUT THE GREAT BASIN FOR A COUPLE
OF DAYS NOW SO CONFIDENCE IS MODERATE FOR AN INTERESTING WX SYSTEM
TO UNFOLD LATE IN THE WEEK INTO THE WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 950 PM MST SAT NOV 16 2013
PRECIPITATION WILL CONTINUE TONIGHT WITH PERIODS OF LOWERED
CIGS AND LOWERED VSBYS. WIDESPREAD MTN SNOW SHOWERS WILL BECOME
SCT TOWARDS MORNING. FOG MAY DEVELOP BETWEEN SNOW SHOWERS KEEPING
VISIBILITY DOWN INTO EARLY SUNDAY MORNING WITH GRADUAL IMPROVEMENT
THEREAFTER. EXPECT WIDESPREAD MVFR CIGS AND VSBYS WITH THE HEAVIER
SHOWERS WITH MOUNTAINS FQTLY OBSCD INTO SUNDAY MORNING. LOCAL IFR TO
LIFR CIGS WILL BE FOUND NEAR THE STRONGER SHOWERS. IN
ADDITION...GUSTY NORTHWEST WINDS WILL BE COMMON ACROSS THE
REGION...WITH SPEEDS EXCEEDING 40 KTS AT AND ABOVE MTN TOP LEVEL.
EXPECT AREAS OF MODERATE TO STRONG TURBULENCE THROUGH THIS PERIOD.
PRECIPITATION AND GUSTY WINDS WILL END THROUGHOUT THE MORNING
SUNDAY FROM WEST TO EAST WITH VFR CONDITIONS EXPECTED SUNDAY
AFTERNOON AND EVENING.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL 6 AM MST SUNDAY FOR COZ003-005-009-
014-017-018.
WINTER STORM WARNING UNTIL 6 AM MST SUNDAY FOR COZ012-019.
WINTER STORM WARNING UNTIL 11 AM MST SUNDAY FOR COZ004-010-013.
UT...NONE.
&&
$$
UPDATE...JOE
SHORT TERM...CC
LONG TERM...JAM
AVIATION...JOE
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
334 AM EST SUN NOV 17 2013
.UPDATE...
AVIATION SECTION UPDATED.
&&
.SYNOPSIS...
ISSUED AT 138 PM EST SAT NOV 16 2013
A POTENT AND STRENGTHENING LOW PRESSURE SYSTEM WILL LIFT NORTHEAST
OVER THE WESTERN GREAT LAKES LATE SUNDAY. AN ASSOCIATED STRONG COLD
FRONT WILL SWEEP EAST ACROSS CENTRAL INDIANA SUNDAY AFTERNOON AND
EVENING. INCREASING MOISTURE STREAMING NORTHWARD AHEAD OF THE FRONT
WILL INTERACT WITH THE FRONT AND RESULT IN WIDESPREAD SHOWERS AND
ALSO THUNDERSTORMS TONIGHT THROUGH SUNDAY EVENING. THERE IS ALSO A
MODERATE RISK OF SEVERE WEATHER SUNDAY AND SUNDAY EVENING WITH
DAMAGING WINDS THE MAIN THREAT ALONG WITH HAIL AND ISOLATED
TORNADOES. HIGH PRESSURE WILL BUILD IN NEXT WEEK WITH DRY CONDITIONS
AND NORMAL TO BELOW NORMAL TEMPERATURES. THE NEXT CHANCE OF SHOWERS
WILL BE LATE IN THE WEEK AND INTO THE WEEKEND AS ANOTHER COLD FRONT
TAKES AIM AT THE OHIO VALLEY.
&&
.NEAR TERM /OVERNIGHT/...
ISSUED AT 1007 PM EST SAT NOV 16 2013
RAIN SHOWERS BECOME MORE ORGANIZED AND INCREASING IN COVERAGE
ACROSS THE WESTERN HALF OF THE FORECAST AREA THIS EVENING AS
STRONG LOW LEVEL JET APPROACHES FROM THE WEST. WINDS HAVE STEADILY
INCREASED THROUGH THE EVENING...WITH GUSTS TO 20-25MPH BECOMING
MORE COMMON. TEMPS REMAINED PRIMARILY IN THE UPPER 50S AT 0230Z.
EVENING SURFACE ANALYSIS INDICATING AN OCCLUDING LOW PRESSURE
SYSTEM OVER MINNESOTA WITH A SECONDARY LOW EJECTING INTO THE
CENTRAL PLAINS. A SUBTLE WARM FRONT EXTENDING FROM THE OCCLUDED
LOW ACROSS CENTRAL ILLINOIS AND SOUTHWEST INDIANA WILL LIFT NORTH
ACROSS THE FORECAST AREA OVERNIGHT. BROAD 55-60KT 850MB JET WILL
TRANSPORT DEEP MOISTURE INTO THE REGION TONIGHT...WITH
MESOANALYSIS INDICATING A PLUME OF 1.2-1.4 IN PRECIP WATER VALUES
POISED TO EXPAND ACROSS THE FORECAST AREA WITHIN THE NEXT FEW
HOURS. BOTH THE HRRR AND THE WRF-NMM BOTH CONSISTENT IN EXPANDING
PRECIP OVER CENTRAL INDIANA INTO THE OVERNIGHT...WITH WIDESPREAD
RAIN FROM 06-12Z. COULD SEE LOCALLY HEAVY RAINFALL CONSIDERING THE
HIGH PRECIP WATER VALUES WITH POTENTIAL FOR MANY LOCATIONS TO PICK
UP 0.50 TO 1 INCH OVERNIGHT.
SEEING A SLOW EXPANSION IN LIGHTNING STRIKES OVER THE MID
MISSISSIPPI VALLEY AS WELL AS ELEVATED INSTABILITY INCREASES. WILL
CONTINUE WITH THE ISOLATED THUNDER MENTION OVERNIGHT. SURFACE
BASED CONVECTION SHOULD REMAIN TO THE WEST OF THE WABASH RIVER
THROUGH DAYBREAK. POTENTIAL DOES EXIST LATE TONIGHT FOR A FEW
STRONGER STORMS TO PRODUCE HAIL...ESPECIALLY OVER THE LOWER
WABASH VALLEY...BUT OVERALL ANTICIPATE CONVECTION TO REMAIN
SUBSEVERE THROUGH 12Z.
ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
ISSUED AT 138 PM EST SAT NOV 16 2013
OBVIOUS FOCUS FOR THE SHORT TERM WILL BE ON SEVERE WEATHER POTENTIAL
ON SUNDAY AND SUNDAY EVENING AS A CLASSIC FALL SEVERE WEATHER
OUTBREAK LOOKS MORE AND MORE LIKELY WITH DAMAGING WINDS THE MAIN
THREAT...BUT TORNADOES CERTAINLY ARE A CONCERN AS WELL.
MODELS ARE NOW IN GOOD AGREEMENT THAT PACIFIC NORTHWEST TROUGH WILL
BECOME NEGATIVELY TILTED ON SUNDAY CAUSING RAPID INTENSIFICATION OF
A SURFACE LOW PRESSURE SYSTEM. DEEPENING SURFACE LOW WILL LIFT TO
NORTHWEST LOWER MICHIGAN OR THE NORTHERN WATERS OF LAKE MICHIGAN BY
00Z MONDAY. ASSOCIATED COLD FRONT WILL THEN SWEEP QUICKLY EAST
ACROSS CENTRAL INDIANA FROM AROUND 18Z SUNDAY TO 00Z MONDAY. PRIOR
TO THAT...A STALLED COLD FRONT IS EXPECTED TO RETURN NORTH AS A WARM
FRONT ACROSS CENTRAL INDIANA AROUND 12-16Z SUNDAY. UPPER SPEED MAX
TO AROUND 120 KNOTS AROUND THE BASE OF THE TROUGH ALONG WITH
WEAKENING...BUT STILL FORMIDABLE OHIO VALLEY UPPER JET WILL PROVIDE
BROAD DILUENT FLOW ON TOP OF WARM CONVEYOR BELT/60 PLUS KNOT LOW
LEVEL JET AHEAD OF THE COLD FRONT. VERY STRONG WIND SHEAR /40 KNOTS
OR MORE FROM 1000-700 MILLIBARS AND 60 KNOTS OR MORE FROM 1000-500
MILLIBARS/ ALONG WITH LONG CURVED HODOGRAPHS AND VERY HIGH HELICITY
NUMBERS OVER 300 METERS SQUARED PER SECONDS SQUARED WILL PROVIDE
AMPLE SPIN IN THE ATMOSPHERE FOR TORNADIC ACTIVITY GIVEN ENOUGH
INSTABILITY.
REGARDING INSTABILITY...TEMPERATURES IN THE UPPER 60S TO MID 70S
WITH WARM ADVECTION ALONE...DEW POINTS APPROACHING 60
DEGREES...700-500 MILLIBAR LAPSE RATES TO 6 DEGREES CELSIUS PER
KILOMETER OR MORE AND DRY INTRUSION ALOFT SHOULD RESULT IN AT LEAST
SOME SURFACE INSTABILITY DESPITE EXPECTED THICK CLOUD COVER AND
EARLIER OR ONGOING OVERNIGHT AND MORNING CONVECTION. EVEN THE LESS
UNSTABLE...12Z DETERMINISTIC GFS IS NOW FORECASTING 500 J/KG CAPE OR
MORE DURING THE AFTERNOON HOURS BUT WEAKENING SIGNIFICANTLY AFTER
DARK.
BASED ON THE ABOVE...AGREE WITH SPC DAY2 MODERATE RISK AND EXPECT A
SEVERE WEATHER OUTBREAK SUNDAY MORNING THROUGH EARLY SUNDAY EVENING.
WILL HAVE TO WATCH OUT FOR DISCRETE SUPERCELLS ESPECIALLY DURING THE
MORNING NEAR THE SURFACE WARM FRONT AND AFTERNOON IN THE WARM SECTOR
THEN...WITH ELONGATED FRONTOGENESIS OCCURRING NEAR THE COLD
FRONT...SHOULD SEE LINEAR ACTIVITY MOVE THROUGH AROUND 18Z IN THE
NORTHWEST TO 00Z IN THE SOUTHEAST ALONG AND JUST AHEAD OF THE FRONT.
THIS WILL BE MORE OF A WIDESPREAD DAMAGING WIND THREAT BUT WITH ALSO
THE POTENTIAL FOR A FEW BRIEF SPIN UPS IN ANY CIRCULATION COUPLET.
HEAVY RAIN COULD ALSO BE AN ISSUE ESPECIALLY EARLY...BEFORE THE DRY
PUNCH ALOFT MOVES IN. IT WILL ALSO CONTINUE TO BE WINDY...BUT DO NOT
THINK THE HIGHER WINDS AT THE TOP OF THE BOUNDARY LAYER FROM THE
BUFKIT 12Z NAM WILL BE ABLE TO MIX DOWN WITHOUT SUNSHINE.
WILL CONTINUE WITH CATEGORICAL POPS PER MOS AND DROPPING
DRAMATICALLY AFTER 06Z MONDAY AND ALTOGETHER AFTER 06Z. THE REST OF
THE SHORT TERM WILL BE CHARACTERIZED BY DRY WEATHER WITH SLIGHTLY
BELOW NORMAL TEMPERATURES AS CANADIAN HIGH PRESSURE BUILDS IN BEHIND
THE COLD FRONT.
MOS HIGHS IN THE UPPER 40S TO LOWER 50S MONDAY AND ALLBLEND IN THE
40S ON TUESDAY LOOK GOOD. ALSO...SHOULD SEE PLENTY OF SUNSHINE...
ESPECIALLY TUESDAY AS THE HIGH PASSES OVERHEAD.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 147 AM EST SUN NOV 17 2013
ECMWF AND GFS SHOW DRY WEATHER PERSISTING ACROSS CENTRAL INDIANA
ON WEDNESDAY AS HIGH PRESSURE DEPARTS THE AREA. HOWEVER A WET AND
ACTIVE END TO THE NEXT WORK WEEK LOOKS IN STORE AS SEVERAL WEATHER
SYSTEMS LOOKS TO PUSH ACROSS THE REGION STARTING ON THURSDAY AND
CONTINUING THROUGH SATURDAY. SEVERAL UPPER LEVEL WEATHER SYSTEMS
WITH A MOIST SOUTHWEST FLOW IN PLACE ALOFT WILL PROVIDE SEVERAL
CHANCES AT SHOWERS STARTING ON THURSDAY AND AGAIN ON FRIDAY AS A
WARM FRONTAL BOUNDARY PASSES ACROSS THE OHIO VALLEY.
THE GFS AND ECMWF SHOW A STRONGER COLD FRONT PUSHING ACROSS THE
REGION ON FRIDAY NIGHT...GIVING US ANOTHER SHOT AT PRECIP...ALONG
WITH MUCH COLDER AIR IN THE WAKE OF THE FRONT FOR NEXT WEEKEND.
&&
.AVIATION /DISCUSSION FOR THE 170900Z IND TAF UPDATE/...
IFR CONDITIONS ARE EXPECTED TO IMPROVE TO MVFR CIGS OR BETTER AS
THE CURRENT WAVE OF PRECIP OVER EASTERN AND SOUTHERN INDIANA
DEPARTS TO THE EAST. HAVE UPDATED THE TAFS IN THE SHORT TERM TO
REFLECT THESE EXPECTED TRENDS.
/DISCUSSION FOR THE 170600Z TAFS/...
ISSUED AT 1130 PM EST SAT NOV 16 2013
UPPER DISTURBANCE CURRENTLY LIFTING OUT OF NORTHERN MISSOURI WITH
INCREASING RAIN/EMBEDDED CONVECTION ASSOCIATED WITH IT. THIS
DISTURBANCE...COUPLED WITH LIFT ALONG A STRONG LOW LEVEL JET AND A
PLUME OF STEEPER MID LEVEL LAPSE RATES ADVECTING INTO THE
AREA...SUGGEST FAIRLY WIDESPREAD RAIN/EMBEDDED CONVECTION SHOULD
AFFECT THE TAF SITES OVERNIGHT. THIS DISTURBANCE EXPECTED TO
CONTINUE PUSHING OFF TO THE NORTHEAST EARLY SUNDAY...SO
RAIN/CONVECTIVE THREAT SHOULD DIMINISH AROUND SUNRISE OR SHORTLY
AFTER. BRIEF PERIODS OF IFR VISIBILITY RESTRICTIONS EXPECTED WITHIN
THE HEAVIER CELLS.
OTHERWISE...STRONG LOW LEVEL JET OF 55-60 KTS EXPECTED TO MOVE
OVERHEAD OVERNIGHT. STARTING TO SEE WIND GUSTS REACH THE
SURFACE...SO DOUBTFUL THERE IS MUCH OF A CHANCE OF THE NOCTURNAL
INVERSION DEVELOPING. AS A RESULT...DON/T THINK LOW LEVEL WIND SHEAR
WILL REACH CRITERIA.
OUTSIDE OF ANY CONVECTION...EXPECTING CEILINGS GENERALLY AROUND 020
THROUGH MIDDAY ON SUNDAY. SURFACE WIND GUSTS 25-30 KTS FROM 170-190
DEGREES EXPECTED THROUGH THE LATE MORNING...WITH MODELS SUGGEST SOME
GUSTS AROUND 35 KTS TOWARDS MIDDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM NOON TODAY TO 9 PM EST THIS EVENING FOR
INZ021-028>031-035>049-051>057-060>065-067>072.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM....PUMA
AVIATION...JAS
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
158 AM EST SUN NOV 17 2013
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 138 PM EST SAT NOV 16 2013
A POTENT AND STRENGTHENING LOW PRESSURE SYSTEM WILL LIFT NORTHEAST
OVER THE WESTERN GREAT LAKES LATE SUNDAY. AN ASSOCIATED STRONG COLD
FRONT WILL SWEEP EAST ACROSS CENTRAL INDIANA SUNDAY AFTERNOON AND
EVENING. INCREASING MOISTURE STREAMING NORTHWARD AHEAD OF THE FRONT
WILL INTERACT WITH THE FRONT AND RESULT IN WIDESPREAD SHOWERS AND
ALSO THUNDERSTORMS TONIGHT THROUGH SUNDAY EVENING. THERE IS ALSO A
MODERATE RISK OF SEVERE WEATHER SUNDAY AND SUNDAY EVENING WITH
DAMAGING WINDS THE MAIN THREAT ALONG WITH HAIL AND ISOLATED
TORNADOES. HIGH PRESSURE WILL BUILD IN NEXT WEEK WITH DRY CONDITIONS
AND NORMAL TO BELOW NORMAL TEMPERATURES. THE NEXT CHANCE OF SHOWERS
WILL BE LATE IN THE WEEK AND INTO THE WEEKEND AS ANOTHER COLD FRONT
TAKES AIM AT THE OHIO VALLEY.
&&
.NEAR TERM /OVERNIGHT/...
ISSUED AT 1007 PM EST SAT NOV 16 2013
RAIN SHOWERS BECOME MORE ORGANIZED AND INCREASING IN COVERAGE
ACROSS THE WESTERN HALF OF THE FORECAST AREA THIS EVENING AS
STRONG LOW LEVEL JET APPROACHES FROM THE WEST. WINDS HAVE STEADILY
INCREASED THROUGH THE EVENING...WITH GUSTS TO 20-25MPH BECOMING
MORE COMMON. TEMPS REMAINED PRIMARILY IN THE UPPER 50S AT 0230Z.
EVENING SURFACE ANALYSIS INDICATING AN OCCLUDING LOW PRESSURE
SYSTEM OVER MINNESOTA WITH A SECONDARY LOW EJECTING INTO THE
CENTRAL PLAINS. A SUBTLE WARM FRONT EXTENDING FROM THE OCCLUDED
LOW ACROSS CENTRAL ILLINOIS AND SOUTHWEST INDIANA WILL LIFT NORTH
ACROSS THE FORECAST AREA OVERNIGHT. BROAD 55-60KT 850MB JET WILL
TRANSPORT DEEP MOISTURE INTO THE REGION TONIGHT...WITH
MESOANALYSIS INDICATING A PLUME OF 1.2-1.4 IN PRECIP WATER VALUES
POISED TO EXPAND ACROSS THE FORECAST AREA WITHIN THE NEXT FEW
HOURS. BOTH THE HRRR AND THE WRF-NMM BOTH CONSISTENT IN EXPANDING
PRECIP OVER CENTRAL INDIANA INTO THE OVERNIGHT...WITH WIDESPREAD
RAIN FROM 06-12Z. COULD SEE LOCALLY HEAVY RAINFALL CONSIDERING THE
HIGH PRECIP WATER VALUES WITH POTENTIAL FOR MANY LOCATIONS TO PICK
UP 0.50 TO 1 INCH OVERNIGHT.
SEEING A SLOW EXPANSION IN LIGHTNING STRIKES OVER THE MID
MISSISSIPPI VALLEY AS WELL AS ELEVATED INSTABILITY INCREASES. WILL
CONTINUE WITH THE ISOLATED THUNDER MENTION OVERNIGHT. SURFACE
BASED CONVECTION SHOULD REMAIN TO THE WEST OF THE WABASH RIVER
THROUGH DAYBREAK. POTENTIAL DOES EXIST LATE TONIGHT FOR A FEW
STRONGER STORMS TO PRODUCE HAIL...ESPECIALLY OVER THE LOWER
WABASH VALLEY...BUT OVERALL ANTICIPATE CONVECTION TO REMAIN
SUBSEVERE THROUGH 12Z.
ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
ISSUED AT 138 PM EST SAT NOV 16 2013
OBVIOUS FOCUS FOR THE SHORT TERM WILL BE ON SEVERE WEATHER POTENTIAL
ON SUNDAY AND SUNDAY EVENING AS A CLASSIC FALL SEVERE WEATHER
OUTBREAK LOOKS MORE AND MORE LIKELY WITH DAMAGING WINDS THE MAIN
THREAT...BUT TORNADOES CERTAINLY ARE A CONCERN AS WELL.
MODELS ARE NOW IN GOOD AGREEMENT THAT PACIFIC NORTHWEST TROUGH WILL
BECOME NEGATIVELY TILTED ON SUNDAY CAUSING RAPID INTENSIFICATION OF
A SURFACE LOW PRESSURE SYSTEM. DEEPENING SURFACE LOW WILL LIFT TO
NORTHWEST LOWER MICHIGAN OR THE NORTHERN WATERS OF LAKE MICHIGAN BY
00Z MONDAY. ASSOCIATED COLD FRONT WILL THEN SWEEP QUICKLY EAST
ACROSS CENTRAL INDIANA FROM AROUND 18Z SUNDAY TO 00Z MONDAY. PRIOR
TO THAT...A STALLED COLD FRONT IS EXPECTED TO RETURN NORTH AS A WARM
FRONT ACROSS CENTRAL INDIANA AROUND 12-16Z SUNDAY. UPPER SPEED MAX
TO AROUND 120 KNOTS AROUND THE BASE OF THE TROUGH ALONG WITH
WEAKENING...BUT STILL FORMIDABLE OHIO VALLEY UPPER JET WILL PROVIDE
BROAD DILUENT FLOW ON TOP OF WARM CONVEYOR BELT/60 PLUS KNOT LOW
LEVEL JET AHEAD OF THE COLD FRONT. VERY STRONG WIND SHEAR /40 KNOTS
OR MORE FROM 1000-700 MILLIBARS AND 60 KNOTS OR MORE FROM 1000-500
MILLIBARS/ ALONG WITH LONG CURVED HODOGRAPHS AND VERY HIGH HELICITY
NUMBERS OVER 300 METERS SQUARED PER SECONDS SQUARED WILL PROVIDE
AMPLE SPIN IN THE ATMOSPHERE FOR TORNADIC ACTIVITY GIVEN ENOUGH
INSTABILITY.
REGARDING INSTABILITY...TEMPERATURES IN THE UPPER 60S TO MID 70S
WITH WARM ADVECTION ALONE...DEW POINTS APPROACHING 60
DEGREES...700-500 MILLIBAR LAPSE RATES TO 6 DEGREES CELSIUS PER
KILOMETER OR MORE AND DRY INTRUSION ALOFT SHOULD RESULT IN AT LEAST
SOME SURFACE INSTABILITY DESPITE EXPECTED THICK CLOUD COVER AND
EARLIER OR ONGOING OVERNIGHT AND MORNING CONVECTION. EVEN THE LESS
UNSTABLE...12Z DETERMINISTIC GFS IS NOW FORECASTING 500 J/KG CAPE OR
MORE DURING THE AFTERNOON HOURS BUT WEAKENING SIGNIFICANTLY AFTER
DARK.
BASED ON THE ABOVE...AGREE WITH SPC DAY2 MODERATE RISK AND EXPECT A
SEVERE WEATHER OUTBREAK SUNDAY MORNING THROUGH EARLY SUNDAY EVENING.
WILL HAVE TO WATCH OUT FOR DISCRETE SUPERCELLS ESPECIALLY DURING THE
MORNING NEAR THE SURFACE WARM FRONT AND AFTERNOON IN THE WARM SECTOR
THEN...WITH ELONGATED FRONTOGENESIS OCCURRING NEAR THE COLD
FRONT...SHOULD SEE LINEAR ACTIVITY MOVE THROUGH AROUND 18Z IN THE
NORTHWEST TO 00Z IN THE SOUTHEAST ALONG AND JUST AHEAD OF THE FRONT.
THIS WILL BE MORE OF A WIDESPREAD DAMAGING WIND THREAT BUT WITH ALSO
THE POTENTIAL FOR A FEW BRIEF SPIN UPS IN ANY CIRCULATION COUPLET.
HEAVY RAIN COULD ALSO BE AN ISSUE ESPECIALLY EARLY...BEFORE THE DRY
PUNCH ALOFT MOVES IN. IT WILL ALSO CONTINUE TO BE WINDY...BUT DO NOT
THINK THE HIGHER WINDS AT THE TOP OF THE BOUNDARY LAYER FROM THE
BUFKIT 12Z NAM WILL BE ABLE TO MIX DOWN WITHOUT SUNSHINE.
WILL CONTINUE WITH CATEGORICAL POPS PER MOS AND DROPPING
DRAMATICALLY AFTER 06Z MONDAY AND ALTOGETHER AFTER 06Z. THE REST OF
THE SHORT TERM WILL BE CHARACTERIZED BY DRY WEATHER WITH SLIGHTLY
BELOW NORMAL TEMPERATURES AS CANADIAN HIGH PRESSURE BUILDS IN BEHIND
THE COLD FRONT.
MOS HIGHS IN THE UPPER 40S TO LOWER 50S MONDAY AND ALLBLEND IN THE
40S ON TUESDAY LOOK GOOD. ALSO...SHOULD SEE PLENTY OF SUNSHINE...
ESPECIALLY TUESDAY AS THE HIGH PASSES OVERHEAD.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 147 AM EST SUN NOV 17 2013
ECMWF AND GFS SHOW DRY WEATHER PERSISTING ACROSS CENTRAL INDIANA
ON WEDNESDAY AS HIGH PRESSURE DEPARTS THE AREA. HOWEVER A WET AND
ACTIVE END TO THE NEXT WORK WEEK LOOKS IN STORE AS SEVERAL WEATHER
SYSTEMS LOOKS TO PUSH ACROSS THE REGION STARTING ON THURSDAY AND
CONTINUING THROUGH SATURDAY. SEVERAL UPPER LEVEL WEATHER SYSTEMS
WITH A MOIST SOUTHWEST FLOW IN PLACE ALOFT WILL PROVIDE SEVERAL
CHANCES AT SHOWERS STARTING ON THURSDAY AND AGAIN ON FRIDAY AS A
WARM FRONTAL BOUNDARY PASSES ACROSS THE OHIO VALLEY.
THE GFS AND ECMWF SHOW A STRONGER COLD FRONT PUSHING ACROSS THE
REGION ON FRIDAY NIGHT...GIVING US ANOTHER SHOT AT PRECIP...ALONG
WITH MUCH COLDER AIR IN THE WAKE OF THE FRONT FOR NEXT WEEKEND.
&&
.AVIATION /DISCUSSION FOR THE 170600Z TAFS/...
ISSUED AT 1130 PM EST SAT NOV 16 2013
UPPER DISTURBANCE CURRENTLY LIFTING OUT OF NORTHERN MISSOURI WITH
INCREASING RAIN/EMBEDDED CONVECTION ASSOCIATED WITH IT. THIS
DISTURBANCE...COUPLED WITH LIFT ALONG A STRONG LOW LEVEL JET AND A
PLUME OF STEEPER MID LEVEL LAPSE RATES ADVECTING INTO THE
AREA...SUGGEST FAIRLY WIDESPREAD RAIN/EMBEDDED CONVECTION SHOULD
AFFECT THE TAF SITES OVERNIGHT. THIS DISTURBANCE EXPECTED TO
CONTINUE PUSHING OFF TO THE NORTHEAST EARLY SUNDAY...SO
RAIN/CONVECTIVE THREAT SHOULD DIMINISH AROUND SUNRISE OR SHORTLY
AFTER. BRIEF PERIODS OF IFR VISIBILITY RESTRICTIONS EXPECTED WITHIN
THE HEAVIER CELLS.
OTHERWISE...STRONG LOW LEVEL JET OF 55-60 KTS EXPECTED TO MOVE
OVERHEAD OVERNIGHT. STARTING TO SEE WIND GUSTS REACH THE
SURFACE...SO DOUBTFUL THERE IS MUCH OF A CHANCE OF THE NOCTURNAL
INVERSION DEVELOPING. AS A RESULT...DON/T THINK LOW LEVEL WIND SHEAR
WILL REACH CRITERIA.
OUTSIDE OF ANY CONVECTION...EXPECTING CEILINGS GENERALLY AROUND 020
THROUGH MIDDAY ON SUNDAY. SURFACE WIND GUSTS 25-30 KTS FROM 170-190
DEGREES EXPECTED THROUGH THE LATE MORNING...WITH MODELS SUGGEST SOME
GUSTS AROUND 35 KTS TOWARDS MIDDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM NOON TODAY TO 9 PM EST THIS EVENING FOR
INZ021-028>031-035>049-051>057-060>065-067>072.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM....PUMA
AVIATION...JAS
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1130 PM EST SAT NOV 16 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 138 PM EST SAT NOV 16 2013
A POTENT AND STRENGTHENING LOW PRESSURE SYSTEM WILL LIFT NORTHEAST
OVER THE WESTERN GREAT LAKES LATE SUNDAY. AN ASSOCIATED STRONG COLD
FRONT WILL SWEEP EAST ACROSS CENTRAL INDIANA SUNDAY AFTERNOON AND
EVENING. INCREASING MOISTURE STREAMING NORTHWARD AHEAD OF THE FRONT
WILL INTERACT WITH THE FRONT AND RESULT IN WIDESPREAD SHOWERS AND
ALSO THUNDERSTORMS TONIGHT THROUGH SUNDAY EVENING. THERE IS ALSO A
MODERATE RISK OF SEVERE WEATHER SUNDAY AND SUNDAY EVENING WITH
DAMAGING WINDS THE MAIN THREAT ALONG WITH HAIL AND ISOLATED
TORNADOES. HIGH PRESSURE WILL BUILD IN NEXT WEEK WITH DRY CONDITIONS
AND NORMAL TO BELOW NORMAL TEMPERATURES. THE NEXT CHANCE OF SHOWERS
WILL BE LATE IN THE WEEK AND INTO THE WEEKEND AS ANOTHER COLD FRONT
TAKES AIM AT THE OHIO VALLEY.
&&
.NEAR TERM /OVERNIGHT/...
ISSUED AT 1007 PM EST SAT NOV 16 2013
RAIN SHOWERS BECOME MORE ORGANIZED AND INCREASING IN COVERAGE
ACROSS THE WESTERN HALF OF THE FORECAST AREA THIS EVENING AS
STRONG LOW LEVEL JET APPROACHES FROM THE WEST. WINDS HAVE STEADILY
INCREASED THROUGH THE EVENING...WITH GUSTS TO 20-25MPH BECOMING
MORE COMMON. TEMPS REMAINED PRIMARILY IN THE UPPER 50S AT 0230Z.
EVENING SURFACE ANALYSIS INDICATING AN OCCLUDING LOW PRESSURE
SYSTEM OVER MINNESOTA WITH A SECONDARY LOW EJECTING INTO THE
CENTRAL PLAINS. A SUBTLE WARM FRONT EXTENDING FROM THE OCCLUDED
LOW ACROSS CENTRAL ILLINOIS AND SOUTHWEST INDIANA WILL LIFT NORTH
ACROSS THE FORECAST AREA OVERNIGHT. BROAD 55-60KT 850MB JET WILL
TRANSPORT DEEP MOISTURE INTO THE REGION TONIGHT...WITH
MESOANALYSIS INDICATING A PLUME OF 1.2-1.4 IN PRECIP WATER VALUES
POISED TO EXPAND ACROSS THE FORECAST AREA WITHIN THE NEXT FEW
HOURS. BOTH THE HRRR AND THE WRF-NMM BOTH CONSISTENT IN EXPANDING
PRECIP OVER CENTRAL INDIANA INTO THE OVERNIGHT...WITH WIDESPREAD
RAIN FROM 06-12Z. COULD SEE LOCALLY HEAVY RAINFALL CONSIDERING THE
HIGH PRECIP WATER VALUES WITH POTENTIAL FOR MANY LOCATIONS TO PICK
UP 0.50 TO 1 INCH OVERNIGHT.
SEEING A SLOW EXPANSION IN LIGHTNING STRIKES OVER THE MID
MISSISSIPPI VALLEY AS WELL AS ELEVATED INSTABILITY INCREASES. WILL
CONTINUE WITH THE ISOLATED THUNDER MENTION OVERNIGHT. SURFACE
BASED CONVECTION SHOULD REMAIN TO THE WEST OF THE WABASH RIVER
THROUGH DAYBREAK. POTENTIAL DOES EXIST LATE TONIGHT FOR A FEW
STRONGER STORMS TO PRODUCE HAIL...ESPECIALLY OVER THE LOWER
WABASH VALLEY...BUT OVERALL ANTICIPATE CONVECTION TO REMAIN
SUBSEVERE THROUGH 12Z.
ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
ISSUED AT 138 PM EST SAT NOV 16 2013
OBVIOUS FOCUS FOR THE SHORT TERM WILL BE ON SEVERE WEATHER POTENTIAL
ON SUNDAY AND SUNDAY EVENING AS A CLASSIC FALL SEVERE WEATHER
OUTBREAK LOOKS MORE AND MORE LIKELY WITH DAMAGING WINDS THE MAIN
THREAT...BUT TORNADOES CERTAINLY ARE A CONCERN AS WELL.
MODELS ARE NOW IN GOOD AGREEMENT THAT PACIFIC NORTHWEST TROUGH WILL
BECOME NEGATIVELY TILTED ON SUNDAY CAUSING RAPID INTENSIFICATION OF
A SURFACE LOW PRESSURE SYSTEM. DEEPENING SURFACE LOW WILL LIFT TO
NORTHWEST LOWER MICHIGAN OR THE NORTHERN WATERS OF LAKE MICHIGAN BY
00Z MONDAY. ASSOCIATED COLD FRONT WILL THEN SWEEP QUICKLY EAST
ACROSS CENTRAL INDIANA FROM AROUND 18Z SUNDAY TO 00Z MONDAY. PRIOR
TO THAT...A STALLED COLD FRONT IS EXPECTED TO RETURN NORTH AS A WARM
FRONT ACROSS CENTRAL INDIANA AROUND 12-16Z SUNDAY. UPPER SPEED MAX
TO AROUND 120 KNOTS AROUND THE BASE OF THE TROUGH ALONG WITH
WEAKENING...BUT STILL FORMIDABLE OHIO VALLEY UPPER JET WILL PROVIDE
BROAD DILUENT FLOW ON TOP OF WARM CONVEYOR BELT/60 PLUS KNOT LOW
LEVEL JET AHEAD OF THE COLD FRONT. VERY STRONG WIND SHEAR /40 KNOTS
OR MORE FROM 1000-700 MILLIBARS AND 60 KNOTS OR MORE FROM 1000-500
MILLIBARS/ ALONG WITH LONG CURVED HODOGRAPHS AND VERY HIGH HELICITY
NUMBERS OVER 300 METERS SQUARED PER SECONDS SQUARED WILL PROVIDE
AMPLE SPIN IN THE ATMOSPHERE FOR TORNADIC ACTIVITY GIVEN ENOUGH
INSTABILITY.
REGARDING INSTABILITY...TEMPERATURES IN THE UPPER 60S TO MID 70S
WITH WARM ADVECTION ALONE...DEW POINTS APPROACHING 60
DEGREES...700-500 MILLIBAR LAPSE RATES TO 6 DEGREES CELSIUS PER
KILOMETER OR MORE AND DRY INTRUSION ALOFT SHOULD RESULT IN AT LEAST
SOME SURFACE INSTABILITY DESPITE EXPECTED THICK CLOUD COVER AND
EARLIER OR ONGOING OVERNIGHT AND MORNING CONVECTION. EVEN THE LESS
UNSTABLE...12Z DETERMINISTIC GFS IS NOW FORECASTING 500 J/KG CAPE OR
MORE DURING THE AFTERNOON HOURS BUT WEAKENING SIGNIFICANTLY AFTER
DARK.
BASED ON THE ABOVE...AGREE WITH SPC DAY2 MODERATE RISK AND EXPECT A
SEVERE WEATHER OUTBREAK SUNDAY MORNING THROUGH EARLY SUNDAY EVENING.
WILL HAVE TO WATCH OUT FOR DISCRETE SUPERCELLS ESPECIALLY DURING THE
MORNING NEAR THE SURFACE WARM FRONT AND AFTERNOON IN THE WARM SECTOR
THEN...WITH ELONGATED FRONTOGENESIS OCCURRING NEAR THE COLD
FRONT...SHOULD SEE LINEAR ACTIVITY MOVE THROUGH AROUND 18Z IN THE
NORTHWEST TO 00Z IN THE SOUTHEAST ALONG AND JUST AHEAD OF THE FRONT.
THIS WILL BE MORE OF A WIDESPREAD DAMAGING WIND THREAT BUT WITH ALSO
THE POTENTIAL FOR A FEW BRIEF SPIN UPS IN ANY CIRCULATION COUPLET.
HEAVY RAIN COULD ALSO BE AN ISSUE ESPECIALLY EARLY...BEFORE THE DRY
PUNCH ALOFT MOVES IN. IT WILL ALSO CONTINUE TO BE WINDY...BUT DO NOT
THINK THE HIGHER WINDS AT THE TOP OF THE BOUNDARY LAYER FROM THE
BUFKIT 12Z NAM WILL BE ABLE TO MIX DOWN WITHOUT SUNSHINE.
WILL CONTINUE WITH CATEGORICAL POPS PER MOS AND DROPPING
DRAMATICALLY AFTER 06Z MONDAY AND ALTOGETHER AFTER 06Z. THE REST OF
THE SHORT TERM WILL BE CHARACTERIZED BY DRY WEATHER WITH SLIGHTLY
BELOW NORMAL TEMPERATURES AS CANADIAN HIGH PRESSURE BUILDS IN BEHIND
THE COLD FRONT.
MOS HIGHS IN THE UPPER 40S TO LOWER 50S MONDAY AND ALLBLEND IN THE
40S ON TUESDAY LOOK GOOD. ALSO...SHOULD SEE PLENTY OF SUNSHINE...
ESPECIALLY TUESDAY AS THE HIGH PASSES OVERHEAD.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
ISSUED AT 219 PM EST SAT NOV 16 2013
MODELS CONTINUE TO HOLD ONTO HIGH PRESSURE EARLY IN THE LONG TERM
PERIOD...WITH A TREND TOWARD WETTER FORECASTS LATE IN THE WEEK AND
INTO THE WEEKEND. INITIALIZATION PROVIDED SLIGHT CHANCE TO LOW
CHANCE POPS FROM WEDNESDAY NIGHT ONWARD...AND CANNOT REALLY ARGUE
WITH IT...ALTHOUGH THE LENGTH OF TIME POPS ARE IN MAY BE A BIT
OVERDONE. THIS WILL BE REFINED AS THE WEEK WEARS ON.
QUASIZONAL FLOW MUCH OF THE PERIOD SUGGESTS TEMPS NEAR
CLIMATOLOGY...AND INITIALIZATION HANDLED THIS WELL.
&&
.AVIATION /DISCUSSION FOR THE 170600Z TAFS/...
ISSUED AT 1130 PM EST SAT NOV 16 2013
UPPER DISTURBANCE CURRENTLY LIFTING OUT OF NORTHERN MISSOURI WITH
INCREASING RAIN/EMBEDDED CONVECTION ASSOCIATED WITH IT. THIS
DISTURBANCE...COUPLED WITH LIFT ALONG A STRONG LOW LEVEL JET AND A
PLUME OF STEEPER MID LEVEL LAPSE RATES ADVECTING INTO THE
AREA...SUGGEST FAIRLY WIDESPREAD RAIN/EMBEDDED CONVECTION SHOULD
AFFECT THE TAF SITES OVERNIGHT. THIS DISTURBANCE EXPECTED TO
CONTINUE PUSHING OFF TO THE NORTHEAST EARLY SUNDAY...SO
RAIN/CONVECTIVE THREAT SHOULD DIMINISH AROUND SUNRISE OR SHORTLY
AFTER. BRIEF PERIODS OF IFR VISIBILITY RESTRICTIONS EXPECTED WITHIN
THE HEAVIER CELLS.
OTHERWISE...STRONG LOW LEVEL JET OF 55-60 KTS EXPECTED TO MOVE
OVERHEAD OVERNIGHT. STARTING TO SEE WIND GUSTS REACH THE
SURFACE...SO DOUBTFUL THERE IS MUCH OF A CHANCE OF THE NOCTURNAL
INVERSION DEVELOPING. AS A RESULT...DON/T THINK LOW LEVEL WIND SHEAR
WILL REACH CRITERIA.
OUTSIDE OF ANY CONVECTION...EXPECTING CEILINGS GENERALLY AROUND 020
THROUGH MIDDAY ON SUNDAY. SURFACE WIND GUSTS 25-30 KTS FROM 170-190
DEGREES EXPECTED THROUGH THE LATE MORNING...WITH MODELS SUGGEST SOME
GUSTS AROUND 35 KTS TOWARDS MIDDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM NOON TO 9 PM EST SUNDAY FOR INZ021-028>031-
035>049-051>057-060>065-067>072.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM....NIELD
AVIATION...JAS
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
326 AM EST SUN NOV 17 2013
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/HYDRO/MARINE
.SYNOPSIS...
ISSUED AT 326 AM EST SUN NOV 17 2013
PEOPLE IN SOUTHWEST LOWER MICHIGAN SHOULD PAY ATTENTION TO THE
WEATHER TODAY BECAUSE IT LOOKS LIKE WE/RE GOING TO SEE A SIGNIFICANT
WIND EVENT. A HIGH WIND WARNING IS IN EFFECT FOR ALL OF SOUTHWEST
LOWER MICHIGAN FROM 4 PM THIS AFTERNOON THROUGH 4 AM MONDAY.
A STRONG AUTUMN STORM WILL MOVE STRENGTHEN AS IT MOVES FROM IOWA
TOWARD THE LEELANAU PENINSULA. SHOWERS AND THUNDERSTORMS WILL
CONTINUE TO DEVELOP TODAY AS A WARM FRONT MOVES NORTH. HOWEVER THIS
AFTERNOON...STORMS WILL LIKELY BECOME STRONG TO SEVERE AS VERY
STRONG DYNAMICS TAP INTO A MOISTURE RICH AIRMASS AHEAD OF THE
APPROACHING COLD FRONT. WIND GUSTS IN EXCESS OF 60 MPH ARE POSSIBLE
THIS AFTERNOON ALONG WITH ISOLATED TORNADOES. THE STORM PREDICTION
CENTER MAINTAINS A MODERATE RISK OF SEVERE STORMS ACROSS SOUTHWEST
LOWER MICHIGAN TODAY WITH A HIGH RISK JUST TO THE SOUTH.
MIXED RAIN/SNOW SHOWERS ARE EXPECTED MONDAY AS HIGHS FALL BACK TO
THE LOWER 40S.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 326 AM EST SUN NOV 17 2013
LATEST MODEL RUNS DIDN/T CHANGE THE THINKING THAT WE/RE STARING AT A
SIGNIFICANT WIND THREAT TODAY. STRONG TO SEVERE STORMS ARE POSSIBLE
ESPECIALLY THIS AFTERNOON FOLLOWED BY STRONG GRADIENT WINDS BEHIND
THE COLD FRONT LATE AFTERNOON AND EVENING. AS A RESULT WE ISSUED A
HIGH WIND WARNING THAT/S IN EFFECT FROM 4 PM TODAY THROUGH 4 AM
MONDAY.
A NEGATIVELY TILTED TROUGH WILL APPROACH THE GREAT LAKES. SFC LOW
PRESSURE IN THE MISSOURI VALLEY WILL MOVE TOWARD THE LEELANAU
PENINSULA LATE TODAY. A WARM FRONT LIFTING NORTH WILL BE AN INITIAL
FOCUS FOR CONVECTION. HOWEVER THE MAIN SHOW WILL BE THIS AFTERNOON
AHEAD OF THE COLD FRONT. A LOW LEVEL JET NEAR 65 KNOTS COUPLED WITH
A MID LEVEL JET NEAR 95 KNOTS WILL GENERATE SIGNIFICANT SHEAR THIS
AFTERNOON. IN ADDITION THE LEFT EXIT REGION OF THE UPPER JET WILL
MOVE OVER THE CWA LATE THIS AFTERNOON. IF WE CAN REALIZE CLOSE TO
THE 800 J/KG MLCAPE THE MODELS INDICATE WE SHOULD HAVE MORE THAN
ENOUGH FORCING AND ORGANIZATION FOR SUPERCELLS TO DEVELOP AHEAD OF
THE COLD FRONT. THE STRONG SHORT WAVE MOVING IN AT THE SAME TIME
WILL ONLY AID IN THE LIFT. SPC MAINTAINS A MODERATE RISK FOR SEVERE
STORMS WITH A HIGH RISK JUST SOUTH OF THE CWA. CAN/T ARGUE WITH
THAT. THE HRRR SHOWS A BROKEN LINE OF STORMS ARRIVING AT THE SHORE
AROUND 20Z. THIS TIMING IS CONSISTENT WITH OTHER MODELS. THE MAIN
SEVERE THREAT LOOKS TO BE FROM 20Z THROUGH 01Z. AFTER THE COLD FRONT
SWEEPS THROUGH THE ATTENTION WILL TURN TO SYNOPTIC WINDS.
THE WIND THREAT WILL CONTINUE THIS EVENING. NAM SHOWS 3 HRLY
PRESSURE RISES IN THE 9-10 MB RANGE WHICH IS PRETTY HIGH AND SHOULD
RESULT IN HIGH WIND WARNING TYPE WINDS...ESPECIALLY ALONG THE COAST
WHERE GUSTS TO 55-65 MPH ARE POSSIBLE. STRONG COLD ADVECTION WILL
HELP TO PULL DOWN THE 55 KNOTS SEEN AT 900 FEET ON BUFKIT WIND
PROFILES. SURE SEEMS LIKE SCATTERED POWER OUTAGES WILL BE POSSIBLE
FROM THIS AFTERNOON THROUGH TONIGHT. WINDS WILL DIMINISH LATE
TONIGHT.
MIXED RAIN/SNOW SHOWERS POSSIBLE MONDAY/TUESDAY AS HIGHS ONLY CLIMB
INTO THE LOWER 40S.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 326 AM EST SUN NOV 17 2013
NO BIG STORMS IN THE EXTENDED. BUMPED UP MAXES A BIT ON WEDNESDAY AS
EURO HAS 850 MB TEMPS AROUND 5C WHICH LOOKS REASONABLE GIVEN DEEP
SOUTHERLY FLOW. ENOUGH MOISTURE MAY BE DRAWN NORTHWARD TO BRING SOME
SHOWERS BY WEDNESDAY NIGHT INTO THURSDAY AS IT POOLS IN FRONT OF
ADVANCING COLD FRONT.
COLDER AIR FILTERS IN FOR THURSDAY NIGHT AND FRIDAY WITH PRECIP
TRANSITIONING TO SNOW BY FRIDAY NIGHT. FORECAST CONFIDENCE IN THE
DETAILS IS LOW WITH POOR RUN TO RUN CONSISTENCY FOR FRIDAY AND
SATURDAY. THE GFS HAS A SFC LOW AND SECONDARY COLD FRONT COMING
THROUGH FRIDAY WHILE THE EURO IS FURTHER NORTH AND SLOWER WITH THE
LOW. SHOULD BE COLD ENOUGH FOR ALL SNOW BY FRIDAY NIGHT AND SATURDAY
IN EITHER SCENARIO.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1149 PM EST SAT NOV 16 2013
INITIAL BATCH OF SHOWER PUSHING THROUGH THE REGION AT THIS TIME
WITH WIDESPREAD MVFR AND SOME IFR STARTING TO SHOW UP. THE TREND
WILL BE MORE IFR THROUGH THE NIGHT...THE WILL PERSIST FOR MUCH OF
SUNDAY. THUNDERSTORMS WILL BECOME MORE LIKELY LATE TONIGHT AND
INTO SUNDAY AS THE ATMOSPHERE DESTABILIZES. THE COLD FRONT PUSHES
THROUGH LATER SUNDAY SENDING THE STORMS OFF TO THE EAST OF KLAN BY
00Z. WINDS WILL GUSTS WELL OVER 25 KNOTS AT TIMES SUNDAY AND
ESPECIALLY SUNDAY NIGHT. GUSTS OF 40 KNOTS APPEAR LIKELY
ACCOMPANYING THE STORMS AND ALSO BEHIND THE COLD FRONT FOR SUNDAY
EVENING.
&&
.MARINE...
ISSUED AT 326 AM EST SUN NOV 17 2013
UPGRADED THE GALE WARNING TO A STORM WARNING. IN ADDITION TO STRONG
TO SEVERE THUNDERSTORMS TODAY STRONG GRADIENT WINDS WILL DEVELOP
BEHIND A COLD FRONT LATE THIS AFTERNOON. WEST STORM FORCE WINDS TO
55 KNOTS ARE EXPECTED THROUGH THE EARLY OVERNIGHT HOURS BEFORE
DECREASING TO 40 KNOT GALES. WAVES WILL BUILD TO 10 TO 15 FEET
TONIGHT.
&&
.HYDROLOGY...
ISSUED AT 326 AM EST SUN NOV 17 2013
HEAVY RAINFALL POSSIBLE IN STORMS TODAY...ESPECIALLY THIS AFTERNOON.
LOOK FOR ADDITIONAL RAINFALL ACCUMULATIONS AROUND AN INCH THROUGH
EARLY EVENING. THIS LIKELY WON`T CAUSE RIVER FLOODING. HOWEVER
LOCALIZED FLOODING MAY DEVELOP IN POOR DRAINAGE AREAS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...HIGH WIND WARNING FROM 4 PM THIS AFTERNOON TO 4 AM EST MONDAY
FOR MIZ037>040-043>046-050>052-056>059-064>067-071>074.
LM...STORM WARNING FROM 4 PM THIS AFTERNOON TO 4 AM EST MONDAY FOR
LMZ844>849.
GALE WARNING UNTIL 4 PM EST THIS AFTERNOON FOR LMZ844>849.
&&
$$
SYNOPSIS...93
SHORT TERM...93
LONG TERM...OSTUNO
AVIATION...MJS
HYDROLOGY...93
MARINE...93
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1134 PM CST SAT NOV 16 2013
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 240 PM CST SAT NOV 16 2013
FIRST WAVE OF -RA/-DZ...AND EVEN A FEW THUNDERSTORMS THAT DEVELOPED
ALONG THE LEADING EDGE OF THE STRONG VERTICAL LIFT ACROSS EC/SC MN
EARLIER THIS AFTN. VISIBLE SATELLITE IMAGERY THIS AFTN INDICATED THE
DRIER AIR MOVING ACROSS NW IOWA WHICH WILL IMPACT FAR SOUTHERN MN
THIS EVENING. SOME BREAKS IN THE CLD CVR ARE LIKELY WITH THIS AREA
OF DRIER AIR...BUT HOW FAR NORTH THIS CLEARING DEVELOPS REMAINS
UNCERTAIN. LATEST RAP HAS AREAS SOUTH OF HWY 212 REMAINING NEARLY
SATURATED BLW 2K THRU TONIGHT.
DEEP SFC LOW IN NE SD WILL SLOWLY MOVE ENE ACROSS CENTRAL MN THIS
EVENING...AND THEN ACROSS NE MN BY SUNDAY MORNING. THIS WILL KEEP
MOST OF CENTRAL MN IN A WEAK FLOW IN THE BOUNDARY LAYER AND
THEREFORE KEEPING LOW CLDS/FOG AND OCCASIONAL DRIZZLE IN THE
FORECAST. NEXT SHRTWV OF INTEREST WILL IMPACT MAINLY THE SE CWA
WITH -RA SUNDAY MORNING...INTO THE EARLY AFTN. FURTHER TO THE
NW...THERE REMAINS ENOUGH ENERGY TO KEEP LOW POPS OVERNIGHT...BUT
WITH CAA ANY PRECIPITATION AMTS WILL REMAIN LIGHT. SOME
-SN/FLURRIES ARE POSSIBLE SUNDAY AFTN BEFORE ANY LEFTOVER
PRECIPITATION ENDS ACROSS CENTRAL MN...BUT NOT CONFIDENT ENOUGH TO
INCLUDE IN THIS FORECAST PACKAGE. TEMPS MAY BE A BIT LOWER IN FAR
SOUTHERN MN IF SKIES CLR. THE LOW CLDS/FOG AND DRIZZLE WILL KEEP
THE REST OF THE CWA WITH LITTLE TEMP CHG UNTIL SUNDAY AS WINDS
SHIFT TO THE W/NW AND BEGIN TO GUST.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 240 PM CST SAT NOV 16 2013
DRIER AIR SHOULD FOLLOW THE FROPA QUICKLY SUNDAY NIGHT WITH
CLEARING SKIES INTO MONDAY. MODELS CONTINUE TO ADVERTISE A
SIDESWIPING OF THE TROUGH MONDAY BEFORE IMPRESSIVE RIDGING
RETURNS TUESDAY AND WEDNESDAY. INCREASED TEMPS A DEGREE OR TWO
MONDAY AND MONDAY NIGHT...BUT SEVERAL DEGREES TUESDAY AS 925 MB
TEMPS OF +4C TO +8C PUSH INTO THE CWA. MIXING TO THAT LEVEL WOULD
YIELD HIGHS IN THE MID/UPPER 50S OVER SOUTHERN MN AND UPPER 40S
OVER WRN WI. DID NOT QUITE GO THAT HIGH YET SINCE THIS IS A
RELATIVELY NEW MODEL TREND...BUT EACH OF THE LAST SEVERAL RUNS
HAVE BEEN GETTING PROGRESSIVELY WARMER.
MODEL CONSISTENCY HAS IMPROVED TODAY WITH A DRY COLD FRONT
PROGGED TO PUSH THROUGH LATE WEDNESDAY OR WEDNESDAY NIGHT. THERMAL
RIDGING IN ADVANCE OF THE FRONT WILL KEEP TEMPERATURES MILD
TUESDAY NIGHT AND WEDNESDAY. A 1040 MB HIGH WILL BUILD IN BEHIND
THE FRONT...BUT MODELS DIFFER A BIT WHERE THIS WILL TRACK WHICH
WILL DETERMINE THE DEGREE OF COLD AIR LATE NEXT WEEK.
AN INVERTED TROUGH PUSHING THROUGH THURSDAY NIGHT OR FRIDAY MAY
BRING A COATING OF SNOW TO THE REGION. INTRODUCED LOW POPS FOR NOW
DURING THIS PERIOD.
AN INTERESTING DEVELOPMENT HAS EMERGED ON THE 12Z ECMWF AND
CANADIAN FOR NEXT WEEKEND. FOLLOWING THE INVERTED TROUGH...A
PROLIFIC 1050-1055MB HIGH BUILDING INTO THE NORTHERN
ROCKIES/NORTHWESTERN PLAINS COULD BRING OUR FIRST SHOT AT VERY
COLD TEMPERATURES. HOWEVER...THE GFS AND FIM MAINTAIN A MUCH
MILDER SOLUTION WITH A WEAKER AND MORE PROGRESSIVE HIGH REMAINING
IN CANADA SO CANNOT TREND TOWARD EITHER SOLUTION YET.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1058 PM CST SAT NOV 16 2013
LOW PRES SHIFTING FROM THE ERN DAKOTAS INTO N-CENTRAL MN AND IT/S
ASSOCIATED MOISTURE PROFILES ARE MAKING FOR A TRICKY TAF SET
TONIGHT. THE OVERALL SCHEME LOOKS TO HAVE KAXN-KSTC SOCKED IN WITH
LIFR FOG AND LOW CEILINGS...WHILE THE REMAINING TAF SITES WILL
REMAIN MVFR TO VFR OVERNIGHT WITH PREVAILING S TO SW WINDS. THIS
AREA OF LOW PRES WILL REACH NE MN BY DAYBREAK...SPREADING THE
DEGRADED CONDS INTO CENTRAL MN...POSSIBLY AFFECTING KMSP ARND 12Z.
CEILINGS DROP INTO MVFR RANGE FOR MOST SITES ARND DAYBREAK...BUT
THE ERN TAF SITES WILL BE MORE SUSCEPTIBLE TO NOT ONLY THE
DEGRADED CONDS BUT ALSO ADDITIONAL ROUNDS OF -RA AS A SECONDARY
LOW PRES CENTER EJECTS FROM THE CENTRAL PLAINS TWD NRN IA/IL. AS
THIS SECONDARY LOW PRES CENTER SHIFTS E...CONDS WILL IMPROVE SUN
AFTN/EVE. HOWEVER...MODELS INDICATE THAT SUBSIDENCE ON THE
BACKSIDE OF THE SECONDARY LOW WITHIN STILL A FAIRLY DEEP MOISTURE
COLUMN WILL RESULT IN MVFR CIGS TMRW NIGHT SO HAVE ADVERTISED AS
SUCH AT ALL SITES. WINDS STILL LOOK TO TAKE A SIGNIFICANT SHIFT
FROM SW TO NW DURG THE DAY TMRW AND WILL SHOW A STRONG INCRS IN
SPEED...APPROACHING 20G30KT. SPEEDS WILL DECRS ONLY SLIGHTLY FOR
TMRW NIGHT...MAKING 15G25KT SPEEDS COMMON SUN NIGHT INTO MON MRNG.
KMSP...CONDS HAVE IMPROVED SIGNIFICANTLY OVER THE PAST 6 HOURS AND
BOTH OBSERVATIONAL TRENDS AND MODELS INDICATE THE THE IMPROVEMENT
WILL LAST THRU MUCH OF THE OVERNIGHT HOURS. CEILINGS DO LOOK TO
DROP BACK INTO MVFR RANGE DURG THE PRE-DAWN HRS BUT IFR CONDS LOOK
MUCH LESS LIKELY. CONDS DROP FURTHER ARND DAYBREAK WITH A MINOR
INVERSION DEVELOPING BUT SUCH CONDITIONS WILL HAVE A SHORT
DURATION AS -RA MOVES IN FROM THE SE AND HELPS SCOUR OUT LOWER
VSBY AND POSSIBLY CEILINGS AS WELL. CONDS THEN CONTINUE TO IMPROVE
AS THE SECONDARY LOW PRES CENTER SHIFTS AWAY...MAKING FOR
STRONG/GUSTY NW WINDS AND CEILINGS EVENTUALLY REACHING VFR.
HOWEVER...ANOTHER ROUND OF MVFR CEILINGS LOOKS FAIRLY LIKELY SUN
NIGHT INTO MON MRNG BEHIND THE DEPARTING SYSTEM.
/OUTLOOK FOR KMSP/
MON...MVFR CIGS EARLY. THEN VFR. WINDS WNW AT 10G15KTS.
TUE...VFR. WINDS SE AT 10KTS.
WED...VFR WITH MVFR AND -RA LATE. WINDS SSW AT 10G15KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JLT
LONG TERM...BORGHOFF
AVIATION...JPC
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
250 AM EST SUN NOV 17 2013
.SYNOPSIS...
THE NEXT COLD FRONT IS EXPECTED TO PUSH THROUGH THE FORECAST
AREA SUNDAY NIGHT INTO EARLY MONDAY...FOLLOWED BY COLD CANADIAN HIGH
PRESSURE BUILDING OVER THE REGION THROUGH THE MIDDLE OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 240 AM EST SUNDAY...A STRONG SHORT WAVE TROUGH WILL SWEEP
ACROSS THE UPPER MID-WEST THIS EVENING. INCREASING SOUTHWESTERLY
FLOW AHEAD OF A POTENT UPPER TROUGH WILL RESULT IN INCREASING
CHANCES OF SHOWER ACTIVITY OVER THE FOREAST AREA. SHOWER CHANCES
WILL BE MAINLY CONFINED TO THE BLUE RIDGE THIS MORNING. BY THE
AFTERNOON THE GFS...SPC 4KM WRF AND THE RAP ALL BRING AN AREA OF
SHOWERS ACROSS THE UPSTATE AND NORTHEAST GEORGIA. THE PCPN IS BEGING
FORCED BY STRONG LLVL WARM ADVECTION. THIS SEAMS REASONABLE AND POPS
RAMP UP QUICKLY EAST OF THE MOUNTAINS INTO THE AFTERNOON HOURS. CAPE
IS LIMITED AND THE ACTIVITY LOOKS AS THROUGH IT MAY BE SLIGHTLY
ELEVATED IN NATURE. SO WHILE THE THERE A CHANCE FOR A TSTM...IT
DOESN/T APPEAR THAT THERE IS ANY SEVERE RISK TODAY OR THIS EVENING.
LATER TONIGHT...HOWEVER...A STRONGLY FORCED LINE OF STORMS IS
EXPECTED TO SWEEP INTO THE NC MOUNTAINS. CONVECTIVE ALLOWING MODELS
GENERALLY HAVE THIS LINE ENTERING THE MOUNTAINS AROUND...OR A LITTLE
AFTER...06 UTC OR AROUND 1 AM. THERE IS DEEP UNIDIRECTIONAL FLOW
BEHIND THE LINE AND IT SHOULD BE MOVING QUITE FAST. EAST OF THE
MOUNTAINS THE NAM HAS A FAIR AMOUNT OF ELEVATED INSTABILITY...ON THE
ORDER OF 500-700 J/KG...THOUGH SURFACE BASED INSTABILITY IS QUITE
LOW. WHILE THE FORECING WILL BE STRONGER OVER WESTERN NC...THERE IS
HIGHER INSTABILITY SOUTH OF THE APPALACHIANS. THEREFORE THE LINE MAY
ACTUALLY HAVE A BETTER CHANCE OF PRODUCING SEVERE WEATHER AS IT
MOVES ACROSS NE GEORGIA AND THE WRN UPSTATE. I SUSPECT THE LINE WILL
WEAKEN CONSIDERLY AFTER CROSSING THE MOUNTAINS...MUCH LIKE WHAT THE
00 UTC HIGH RES WRF ARW IS INDICATING. HOWEVER...EVEN A WEAKING LINE
WILL HAVE THE POTENTIAL TO TRANSLATE STRONG WINDS TO THE SFC AS IT
MOVES ACROSS THE FOOTHILLS AND PIEDMONT.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AT 210 AM EST SUNDAY...ON MONDAY MORNING A LOW AMPLITUDE UPPER
TROUGH WILL EXTEND FROM THE GREAT LAKES TO THE GULF STATES. AT THE
SAME TIME...A SURFACE COLD FRONT WILL EXTEND FROM CAPE COD...TO THE
NC OUTER BANKS...TO SOMEWHERE BETWEEN THE SC AND GA PIEDMONT...AND
THE SC AND GA COAST. THE FRONT WILL RAPIDLY MOVE AWAY FROM OUR
MONDAY MORNING...FOLLOWED BY A DRY...NW...WARMING DOWNSLOPE FLOW IN
A TIGHT PRESSURE GRADIENT...AND TEMPERATURES ALMOST 10 DEGREES ABOVE
NORMAL.
THE DEAMPLIFYING UPPER TROUGH WILL MOVE OFFSHORE ON MONDAY
NIGHT...FOLLOWED BY ZONAL FLOW ALOFT. SURFACE WINDS WILL BE SLOW TO
DIMINISH MONDAY NIGHT AS HIGH PRESSURE MOVES UP THE OH VALLEY...BUT
WINDS WILL VEER FROM NW TO N...DECREASING DOWNSLOPE FLOW WARMING. AS
A RESULT..MINIMUM TEMPERATURES MONDAY NIGHT WILL FALL TO NEAR
NORMAL. TUESDAY FEATURES DRY HIGH PRESSURE CENTERED OVER THE UPPER
OH RIVER VALLEY...AND A WEAK PRESSURE GRADIENT TO ITS SOUTH. COOL NE
FLOW WILL LIMIT MAXIMUM TEMPERATURES TO SEVERAL DEGREES BELOW NORMAL.
THE SURFACE HIGH WILL TAKE UP RESIDENCE ALONG THE EASTERN SEABOARD
TUESDAY NIGHT. BOTH THE NAM AND GFS SHOW SOME ADVANCE OF ATLANTIC
MOISTURE INLAND OVER COASTAL SC AND GA...WITH THE NAM MOISTURE
NEATLY REACHING THE UPPER SAVANNAH RIVER VALLEY. THE ECMWF SPREADS
IT MOISTURE FARTHER INLAND LIKE THE NAM...BUT IS FARTHER SOUTH.
UNLESS CLOUD COVER CAN MAKE INROADS OVER OUR AREA...MINIMUM
TEMPERATURES TUESDAY NIGHT WILL BE SEVERAL CATEGORIES BELOW NORMAL.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 145 AM EST SUNDAY...FOR THE PERIOD WEDNESDAY THROUGH SATURDAY.
HIGH PRESSURE IS SHOWN TO BE OVER NEW YORK STATE AT 12Z WEDNESDAY ON
BOTH THE GFS AND ECMWF. THIS WILL GIVE OUR REGION A COOL NE FLOW AS
HIGHS WILL BE ABOUT 10 DEGREES BELOW NORMAL. THE HIGH SHIFTS OFF THE
NEW ENGLAND COAST WITH THE LOW LEVEL WIND FLOW CHANGING FROM NE TO A
VERY LIGHT VARIABLE OR LIGHT EAST FLOW. WEDNESDAY AND WEDNESDAY
NIGHT ARE THE PERIODS IN THIS MEDIUM RANGE THAT HAS BEST MODEL
AGREEMENT. THE REST OF THE FORECAST PERIODS ARE BASED ON A
COMPROMISE FROM THE DAYS 5 TO 7 MODELS.
THE PREVIOUS CANADIAN MODEL HAD A LOW MOVING NE OUT OF THE NRN GULF
ON THURSDAY INTO FRIDAY BRINGING RAIN TO GA AND THE CAROLINAS AHEAD
OF THE FRONT. NONE OF THE OTHER MODELS HAD ANYTHING LIKE THIS. THE
NEWEST CANADIAN HAS BACKED OFF FROM THE LOW AHEAD OF THE FRONT AND
NOW HAS CONVECTION FORMING ALONG GULF COAST FROM TEXAS TO AL
THURSDAY NIGHT AND MOVING IT NORTH TO JOIN THE FRONT LATE FRIDAY
INTO SATURDAY.
THE GFS MAINTAINS SOME WEAK SURFACE RIDGING OVER THE CAROLINAS AND
DELAYS THE COLD FRONT ARRIVING UNTIL SATURDAY. THE GFS HAS SOME
ORGANIZED SHOWER ACTIVITY MOVING INTO THE NC MTNS LATE FRIDAY NIGHT
AND THEN ALL ACTIVITY BREAKS DOWN SATURDAY AS THE FRONT BECOMES MORE
DIFFUSE. IN FACT...THE GFS HAS ALL PRECIP SOUTH OF OUR AREA BY
SATURDAY EVENING WITH DRY AIR SPREADING IN AHEAD OF COLD HIGH
PRESSURE WHICH ORIGINATES FROM ALASKA AND NW CANADA.
THE CURRENT ECMWF HAS PRECIP MOVING INTO THE GREAT SMOKIES THURSDAY
EVENING THEN EXPANDING OVER THE REST OF THE WESTERN CAROLINAS AND NE
GA FRIDAY INTO SATURDAY. THIS RUN OF THE ECMWF MAINTAINS FRONTAL
CONVECTION AS IT CROSSES THE AREA SATURDAY NIGHT WITH AROUND A HALF
INCH QPF. DRY AIR ARRIVES ON SUNDAY ON THE ECMWF. THE NEWEST 00Z RUN
OF THE ECMWF JUST ARRIVED AND IT IS VERY MUCH CLOSER TO THE GFS.
NEWEST RUN HAS A WEAK FRONTAL BAND CROSSING MTNS 12Z SAT AND ACROSS
PIEDMONT 18Z SATURDAY...THEN DRY AIR ALL OVER BY 00Z SUNDAY.
TEMPERATURES WILL BE CLOSE TO OR JUST BELOW NORMALS FRIDAY AND
SATURDAY.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
AT KCLT...SKIES HAVE CLEARED TEMPORARILY AT THE AIRFIELD. JUST A FEW
MILES TO THE WEST THERE IS AN BORDERLINE MVFR/VFR DECK. JUST A FEW
MILES TO THE EAST THERE IS AN EXPANDING AREA OF FOG AND IFR/LIFR
STRATUS AND FOG. BASED ON THE H8 DRYING SEEN ON THE LATEST NAM AND
RUC...WENT WITH TEMPO IFR VSBYS AND LIFR CIGS. ONCE A HIGHER DECK
FINALLY SPREADS BACK IN HOPEFULLY THE LOWER STUFF WILL LIFT FOR A
WHILE. THAT SAID...IFR CIGS ARE EXPECTED TO DEVELOP AGAIN TOWARD 12
UTC AND LAST THROUGH THE MORNING. WINDS WILL BE LIGHT AND VARIABLE
THROUGH THE MORNING HOURS.
A LINE OF THUNDERSTORMS IS EXPECTED TO ENTER THE MOUNTAINS
TONIGHT...BUT AT THIS TIME IT DOESN/T APPEAR THE LINE WILL SURVIVE
IT/S TRIP ACROSS THE HIGH TERRAIN. STILL...A SIGNIFICANT WIND SHIFT
AND GUSTY WINDS MAY ACCOMPANY THE OUTFLOW BNDRY TOWARD MONDAY
MORNING. THIS IS A LITTLE OUTSIDE THE VALID PERIOD OF THE TAF...BUT
IT/S SOMETHING TO WATCH CLOSELY.
ELSEWHERE...VFR CIGS ARE CURRENTLY OVER ALL THE REMAINING TAF SITES.
STRENGTHENING UPSLOPE FLOW WILL HELP THESE CIGS TO GRADUALLY LOWER
DURING THE NIGHT. EXPECT THAT AN MVFR CIG WILL DEVELOP FIRST AROUND
2500 FEET WITH IFR STRATUS DEVELOPING TOWARD MORNING. THE LOW CIGS
ARE THEN EXPECTED TO LAST A LITTLE PAST NOON. SHOWERS WILL BECOME
MORE WIDESPREAD THIS EVENING. A LINE OF THUNDERSTORMS IS EXPECTED TO
ENTER THE MOUNTAINS BETWEEN 06-09 UTC. THE LINE MAY AFFECT KAVL.
EVEN IF THE STORMS WEAKEN...A SHARP WIND SHIFT IS LIKELY TO AFFECT
ALL OF THE TAF SITES A LITTLE BEYOND THE VALID PERIOD OF THE CURRENT
SET OF TAFS.
OUTLOOK...A RETURN TO MUCH DRIER WEATHER IS EXPECTED BY LATE MONDAY.
CONDITIONS SHOULD BE MAINLY VFR FROM MONDAY NIGHT THROUGH THE MIDDLE
OF THE UPCOMING WEEK.
CONFIDENCE TABLE...
07-13Z 13-19Z 19-01Z 01-07Z
KCLT LOW 59% MED 73% MED 79% MED 75%
KGSP MED 72% MED 69% HIGH 83% HIGH 90%
KAVL HIGH 94% MED 77% HIGH 85% HIGH 91%
KHKY HIGH 86% HIGH 82% HIGH 88% HIGH 93%
KGMU MED 71% MED 67% MED 77% HIGH 86%
KAND MED 65% MED 63% HIGH 85% HIGH 86%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.FIRE WEATHER...
A LINE OF THUNDERSTORMS IS EXPECTED TO MOVE ACROSS THE NORTH
CAROLINA MOUNTAINS EARLY MONDAY MORNING. WHILE THE LINE SHOULD
WEAKEN AS IT CROSSES THE MOUNTAINS...THE ACCOMPANYING OUTFLOW
BOUNDARY WOULD RESULT IN WINDS RAPIDLY SHIFTING TO THE WEST OR
NORTHWEST. OVER THE LINVILLE GORGE THIS IS MOST LIKELY TO HAPPEN
BETWEEN 1 AM AND 4 AM MONDAY. IN ADDITION TO SHIFTING WINDS...STRONG
WIND GUSTS ARE ALSO POSSIBLE WITH THE LINE.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...DEO
NEAR TERM...MCAVOY
SHORT TERM...JAT
LONG TERM...DEO
AVIATION...MCAVOY
FIRE WEATHER...MCAVOY
AREA FORECAST DISCUSSION
NWS ALBANY NY
1002 AM EST SUN NOV 17 2013
.SYNOPSIS...
HIGH PRESSURE ALONG THE EASTERN SEABOARD WILL SLIDE OUT TO SEA
TODAY. A POWERFUL STORM WILL MOVE FROM THE UPPER GREAT LAKES
TOWARD JAMES BAY SUNDAY NIGHT INTO MONDAY. IT WILL BRING WINDY
CONDITIONS TO THE REGION...AND DRIVE A COLD FRONT ACROSS THE
REGION MONDAY MORNING. MUCH COLDER AIR WILL POUR INTO THE REGION
MONDAY NIGHT AND TUESDAY WITH SOME CLOUDS AND SNOW SHOWERS. HIGH
PRESSURE WILL BUILD FROM ONTARIO TO THE GULF COAST TUESDAY...THEN
SETTLE OVER OUR REGION MID WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
...SLIGHT RISK FROM SPC HAS BEEN EXPANDED TO INCLUDE THE ENTIRE
REGION THROUGH TONIGHT...
AS OF 930 AM EST...LOW STRATUS AND DRIZZLE HAVE QUICKLY EVOLVED
ACROSS THE SOUTHERN HALF OF OUR COUNTY WARNING AREA AND HAVE
EXPANDED THE POPS AND MENTION OF DRIZZLE THROUGH THE REMAINDER OF
THE MORNING HOURS. TEMPERATURE ANALYSIS REVEALS THE COLDER AIR HAS
REMAINED LOCKED IN ACROSS THE EASTERN GREENS OF SOUTHERN VERMONT
WHERE MID-UPR 30S RESIDE WITH THE WESTERN GREENS WELL INTO THE
50S. SO WE HAVE MODIFIED HOURLY TEMPS A BIT TO MATCH UP BETTER
WITH OBSERVATIONS. PER THE 12Z SOUNDING HERE...AMPLE LOW LEVEL
MOISTURE BELOW THE STRENGTHENING INVERSION AROUND H850 AND
INCREASING LOW LEVEL SHEAR HAS BEEN THE RESULT OF THE DRIZZLE
EXPANDING. THIS IS ALSO CONFIRMED WITH THE LATEST VWP REVEALING
AMPLE LOW LEVEL SHEAR AND NO ECHOES IN THE MID LEVELS /TOO DRY/
BETWEEN 8K-11K FEET.
REGIONAL RADAR SHOWS SHOWERS/PERIODS OF RAIN ACROSS WESTERN AND
CENTRAL NY WITH EXPECTATIONS OF THIS REACHING THE WESTERN MOHAWK
VALLEY AND DACKS LATER THIS MORNING. THIS SHOULD EXPAND ACROSS
MOST OF EASTERN NY AND INTO THE UPSLOPE ENHANCEMENTS OF WESTERN
NEW ENGLAND LATER THIS AFTERNOON PER THE LATEST HRRR REFLECTIVITY.
BROAD INCREASING ISENTROPIC LIFT AND WARM MOIST ADVECTION WILL BE
SURE TO KEEP CLOUDS AND THAT EXPANDING AREA OF SHOWERS IN THE
FORECAST WITH LITTLE CHANGES TO THE POPS/WX FOR THE LATER
AFTERNOON HOURS.
A VERY POWERFUL NEGATIVELY TROUGH AND ASSOCIATED COLD FRONT WILL
BE PLOWING THROUGH THE OHIO VALLEY LATER TODAY. THIS FRONT COULD
MAKE WEATHER HISTORY IN THAT IT COULD SPAWN AN UNUSUAL PLETHORA OF
SEVERE WEATHER IN THOSE AREAS...ESPECIALLY CONSIDERING IT IS MID
NOVEMBER. PLEASE REFER TO THE LATEST OUTLOOKS FROM THE STORM
PREDICATION CENTER.
FOR THE AFTERNOON...IT WILL BECOME NOTICEABLY BREEZIER IN MANY
SPOTS...OVERCAST WITH A CHANCE OF SHOWERS AS LOW LEVEL MOISTURE
INCREASES. PWAT VALUES LOOK TO RAMP UP TO AN INCH BY THE END OF THE
DAY...WHICH WOULD MAKE IT ABOUT 2 STANDARD DEVIATIONS ABOVE NORMAL.
FORCING WILL REMAIN WEAK TODAY.
HIGH TEMPERATURES TODAY WILL BE SIMILAR TO YESTERDAY/S...GENERALLY
IN THE 55 TO 60 RANGE...WELL ABOVE NORMAL.
THE COLD WILL APPROACH WESTERN NEW YORK THIS EVENING. IT WILL HAVE
RUN OUT OF DAYLIGHT AND REALLY ANY GOOD SURFACE INSTABILITY.
HOWEVER...A STRONG LOW LEVEL JET OF OVER 50 MPH AS LOW AS 2000 FEET
OFF THE DECK WILL BE AHEAD OF IT...AND UP TO 75 MPH ABOUT 5,000 FEET
UP! WHILE SURFACE INSTABILITY NEVER REALLY IS THERE...IT DOES
APPEARS THAT THE SHOWALTER INDEX (INSTABILITY FROM THE 850 MB LEVEL)
WILL GO TO ZERO OR EVEN -1 TO -2 ACROSS PORTIONS OF OUR
REGION...JUST AHEAD OF IT OVERNIGHT.
THE STORM PREDICTION CENTER HAS NOW PLACED A SLIGHT RISK OVER OUR
ENTIRE REGION...NAMELY FOR TONIGHT. AT THIS POINT WE FEEL ANY
CONVECTION WOULD BE LOW TOPPED...SCATTERED AT BEST AND CONFINED TO
NEAR THE ACTUAL PASSAGE OF THE COLD FRONT. HOWEVER...IT COULD EASILY
TAP INTO THE VERY POWERFUL WIND FIELD WHICH COULD TRANSLATE TO WIND
GUSTS OVER 50 MPH!
IT IS A GOOD BET THAT A CONVECTIVE LINE (PERHAPS WITHOUT ANY CLOUD
TO GROUND LIGHTNING STRIKES) WILL DEVELOP AHEAD OF THIS COLD FRONT
AND MOVE QUICKLY THROUGH OUR REGION OVERNIGHT. AGAIN THIS LINE COULD
BRING GUSTY WINDS TO ABOUT 50 MPH OR MORE.
WE HAVE INCLUDED THE CHANCE OF THUNDERSTORMS WITH THE FRONT...SOME
OF WHICH MIGHT CONTAIN GUSTY WINDS. WITH THE HIGH PWATS AND STRONG
CONVERGENCE WITH THE FRONT...RAIN COULD BE HEAVY AT TIMES WITH THE
LINE.
WE DID NOT PUT ANY AREA IN A HIGH WIND WATCH. IT LOOKS TO US AS
MUCH OF THE TIME THE GRADIENT OVERNIGHT WILL BE BELOW WIND
ADVISORY THRESHOLDS DUE TO AN INVERSION OVERHEAD (UNTIL THE COLD
FRONT ARRIVES). ONE EXCEPTION COULD THE ADIRONDACKS WHICH COULD
SEE WIND GUSTS EXCEEDING 40 MPH. HOWEVER...WE WERE NOT CONFIDENT
JUST YET IN PLACING THEM INTO A HIGH WIND WATCH. LATER CREWS MIGHT
BE ISSUING ONE LATER ON TODAY.
THE BETTER CHANCE FOR ANY DAMAGING WINDS WOULD BE ALONG THE SQUALL
LINE SHOULD IT FORM.
OVERNIGHT LOWS WILL REMAIN EXCEPTIONALLY MILD FOR THE TIME OF
YEAR...FALLING LITTLE IF ANY...REMAINING IN THE 50S IN MOST AREAS.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
MODEL SUITE DURING THIS PERIOD IS VERY MUCH IN AGREEMENT.
INTENSE STORM IS VERTICAL AND LIFTING QUICKLY NE ACROSS
ONTARIO/QB BORDER REGIONS MONDAY MORNING AS ITS CDFNT HAS CLEARED
THE FCA. CLEARING SHOULD BE RAPID ACROSS FCA AS DRY SLOT
OVERSPREADS REGION. SFC WIND GRADIENT SHIFTS TO WEST AND REMAINS
ABOUT 12MB MON ACROSS NYS. SO BRISK WEST WINDS WITH SOME DOWN
SLOPING AND COMPRESSION WILL FOLLOW FROPA WITH A MILD BUT BRISK
DAY. TEMPS WILL REMAIN IN THE 50S AND LOW TO MID 60S S&E OF ALB.
2NDRY CDFNT AND A STRONG 500 HPA SHORT WV WILL APPROACH TWRD
EVENING WITH CLOUDS INCR FM NW TO SE.
MON NT FLOW WILL SHIFT TO NW BEHIND SECONDARY CDFNT...THEN N AS TROF
AXIS MOVES ACROSS RGN AND CAA INCR WITH SFC HIGH BUILDING FM OH
VLY TO GRTLKS. MODEST LK EFFECT RESPONSE AND UPSLOPE N FLOW OVER
HIR TRRN WILL INCR CLOUDS AND RESULT IN -SHSN N AND W MON NT INTO
TUE MRNG. THIS ACTIVITY WILL END QUICKLY TUESDAY MORNING AS TROF
SHIFTS EAST...UVM FM TROF BCMS DVM...AND SFC FLOW IS MOSTLY
N..BUT WINDS WILL STILL BE VERY BRISK TUES.
THE PERIOD ENDS WITH TRANQUILITY AS SFC HIGH CENTER SHIFTS OVER
RGN WED MORNING...AND RIDGING BUILDS OVER NE USA MIDWEEK. WITH
IDEAL RADIATIONAL COOLING...CLEAR SKIES...LIGHT WINDS...14 HOURS
OF NIGHT...TEMPS WILL DROP TO SINGLE DIGITS N TO LOW 20S SE. MOS
MDL MINS HAVE BEEN TRENDING COLDER FOR THIS PERIOD SINCE LATE LAST
WEEK.
WED WILL START COLD AND REMAIN CHILLY WITH MAX TEMPS 5-10 DEG
BLOW NORMAL. BUT WITH LIGHT WINDS AND LOTS OF SUN WILL BE
RELATIVELY PLEASANT FOR MID NOV.
WED NT WILL BE ANOTHER COLD ONE UNDER THE SFC HIGH CENTER WITH
LOWS 10 TO LOW 20S.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
THE PERIOD FEATURES A FAST ZONAL 500HPA FLOW OVER N TIER OF
USA...ENDING WITH A BREAKING WAVE AND DEEPENING TROF OVER THE EAST.
AS SUCH ITS NOT A HIGH CONFIDENCE EFP AFTER FRIDAY MORNING.
MODEL SUITE BEGINS IN AGREEMENT AT FIRST...BUT SPREADS WIDELY BY END
OF PERIOD WITH MAINLY TIMING ISSUES BETWEEN ECMWF/GEM AND GFS. THUR
500HPA RIDGE FLATTENS INTO ZONAL FLOW. HVWR SFC HIGH REMAINS ALONG E
SEABOARD WITH LT S-SW SFC FLOW. RESULT IS FAIR DAY WITH A SLIGHT
MODERATION IN TEMPS TO NR NORMALS. THU NT A WEAK BACKDOOR CDNFT
DROPS S ACROSS RGN WITH REINFORCING SHOT OF COLD AIR. HWVR CDFNTS
MAGNITUDE AND WIND GRADIENT BEHIND IT OVR RGN FRI VARIES GREATLY FM
BTWN THE ECMWF/GEM/GFS AND HPC. ALL THE GUIDS HAS A GENERALLY FAIR
BUT COOLER DAY. THE EFP PERIOD ENDS WITH A SERIES OF SHORT WVS
DIGGING OUT A TROF AND 500HPA CUT OFF OVER THE EAST. THE GFS PUSHES
THIS STRONG CLIPPER TYPE SYSTEM THROUGH REGION FRI NT INTO SAT
MORNING...WITH STRONG CAA FOR THE WEEKEND. THE ECMWF/GEM AS FAR AS
IT GOES KEEP THE FLOW ZONAL AT 500HPA ...WITH SFC HIGH OVER RGN
FRIDAY AND FRI NT. THESE MODELS HAVE THIS STRONG FROPA AND CAA
COMING THROUGH A DAY LATER ON SAT NT AND SUN. HPC GUIDANCE IS MORE
IN LINE WITH THIS LATER SOLUTION...AND GIVEN LOW CONFIDENCE AT END
OF EFP...SEE NO REASON WHY NOT TO GO WITH IT. SO WILL POPULATE WITH
HPC ON THIS UPDATE.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
A STRONG COLD FRONT WITH A LIKELY LINE OF SHOWERS AND POSSIBLE WILL
IMPACT THE TERMINAL OVERNIGHT.
LOW END MVFR AND IFR CONDITIONS HAVE DEVELOPED AS WE DID AMMEND
THE TAFS ACCORDINGLY. THESE CIGS WILL LIKELY BOUNCE BETWEEN
CATEGORIES FOR THE REMAINDER OF THE DAY ALONG WITH AN INCREASE IN
THE LOW LEVEL JET THAT WILL BE ADDRESSED IN FUTURE UPDATES.
CIGS LOOK TO LIFT BACK TO THE HIGH END OF MVFR LATER IN THE MORNING
AFTER THE MORNING PEAK WITH OVERALL DECENT SURFACE VISIBILITY AS ANY
MIST DISSIPATES. HOWEVER...PATCHES OF DRIZZLE COULD DEVELOP DURING
THE AFTERNOON (NOT REFLECTED IN THE TAFS) BUT USED VCSH AT THAT TIME.
A LIGHT WIND WILL BECOME SOUTH OR SOUTHEAST AROUND 10KTS LATER ON
SUNDAY...WITH GUSTS UP TO 20KTS MAINLY AT KALB AND KPSF.
AS A STRONG COLD FRONT APPROACHES TO NIGHT...THE SOUTH SURFACE
WIND WILL CONTINUE AT 10-15 KTS. STRONGER WINDS ALOFT PROMPTED US TO
INCLUDE WIND SHEAR AT THE KGFL TAF AFTER 00Z. AT THIS POINT...IT
WILL BE A CLOSE CALL AT THE OTHER TAF SITES BUT DID NOT INCLUDE IT
IN JUST YET AS THE DIFFERENTIAL BETWEEN THE SURFACE WIND AND 2000
FEET DID NOT QUITE MEET THE OFFICIAL THRESHOLD...BUT AGAIN IT IS
VERY CLOSE AND PILOTS SHOULD LOOK FOR ANY UPDATES.
SHOWERS SUNDAY NIGHT COULD REDUCE CONDITIONS TO IFR AT
TIMES...ALTHOUGH MVFR LOOKS TO PREDOMINATE. THERE LOOKS TO BE A LINE
OF GUSTY SHOWERS (AND POSSIBLY EVEN THUNDERSTORMS) WITH THE COLD
FRONT AS IT LOOKS TO CROSS THE TAFS BETWEEN ABOUT 08Z-12Z OVERNIGHT.
THE BIGGEST CONCERN COULD BE STRONG GUSTY WINDS ALONG AND JUST
BEHIND THIS FEATURE. WE REFLECTED THIS TREND IN THE TAFS. THE EXACT
TIMING WILL LIKELY BE ADJUSTED A LITTLE AS THIS LINE APPROACHES AND
THE WINDS COULD CERTAINLY BE BRIEFLY STRONGER THAN THE 30KT GUSTS WE
ARE CURRENTLY ADVERTISING.
OUTLOOK...
MONDAY NIGHT AND TUESDAY: LOW OPERATIONAL IMPACT.BREEZY
TUESDAY NIGHT THROUGH THURSDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
TODAY WILL BE THE LAST DAY WE ISSUE THE NFDRS FORECASTS AT 300 PM
THIS AFTERNOON. TOMORROW MORNING WILL BE LAST ISSUANCE OF THE FIRE
WEATHER PRODUCT AND FIRE WEATHER DISCUSSION FOR THIS YEAR.
WE WILL CONTINUE TO POPULATE FIRE WEATHER GRIDS TWO TIMES A DAY FOR
THE REMAINDER OF THE YEAR.
FOR TODAY...HIGH HUMIDITY LEVELS WILL PERSIST ALONG WITH PLENTY OF
CLOUDS...SOME PATCHY MORNING DRIZZLE AND THE CHANCE FOR AFTERNOON
SHOWERS. A SOUTHERLY WIND WILL INCREASE TO 10 TO 15 MPH BY
AFTERNOON.
A STRONG COLD FRONT WILL WORK ACROSS THE REGION OVERNIGHT LIKELY
BRINGING A SQUALL LINE OF HEAVY SHOWERS AND POSSIBLY SOME EMBEDDED
THUNDERSTORMS. MOST PLACES SHOULD RECEIVE A QUARTER INCH OF RAIN OR
MORE. WIND GUSTS COULD BRIEFLY REACH 40 MPH OR MORE WITH THIS LINE.
MOST PLACES WILL DRY OUT QUICKLY BEHIND THE FRONT...ALTHOUGH SOME
SHOWERS COULD LINGER ACROSS MAINLY THE ADIRONDACKS. IT WILL BE
SOMEWHAT WINDY WITH SOUTHWEST WIND BECOMING WESTERLY 10 TO 20 MPH
WITH A FEW HIGHER GUSTS.
DRY AND COLDER WEATHER WILL FOLLOW FOR MUCH OF THE REMAINDER OF THE
WORKWEEK.
&&
.HYDROLOGY...
NO FLOODING OF RIVERS OR STREAMS ARE EXPECTED OVER THE NEXT FIVE
DAYS.
HOWEVER...RAIN COULD FALL HEAVILY ENOUGH OVERNIGHT TO PRODUCE AREAS
OF PONDING WHERE FALLEN LEAVES MIGHT CLOG DRAINS.
TODAY WILL FEATURE SOME PATCHES OF LIGHT DRIZZLE OR RAIN SHOWERS
WITH MOST AREAS EXPECTED TO RECEIVE A TENTH OF AN INCH OF RAINFALL
OR LESS.
A LINE OF SHOWERS AND POSSIBLY EVEN A FEW THUNDERSTORMS WILL WORK
ACROSS THE REGION OVERNIGHT...BRINGING MORE SIGNIFICANT RAINFALL.
RIGHT NOW WE BELIEVE MOST AREAS WILL HAVE AROUND A HALF INCH OF
RAINFALL. THIS WOULD BE ENOUGH TO PRODUCE SOME MINOR RISES ON MANY
RIVERS AND STREAMS SINCE VEGETATION IS NOW COMPLETELY DORMANT.
HOWEVER...RIVERS AND STREAMS WERE RUNNING A BIT BELOW NORMAL...SO IS
VERY UNLIKELY ANY OF THEM WOULD REACH NEAR BANKFULL SINCE IT LOOKS
AS IF THE RAIN IS OUT OF HERE FOR THE MOST PART COME MONDAY.
A FEW ADDITIONAL LIGHT SHOWERS COULD FALL ACROSS THE ADIRONDACKS
THROUGH EARLY TUESDAY...WITH ADDITIONAL AMOUNTS OF RAINFALL UNDER A
QUARTER OF AN INCH. LITTLE OR NO ADDITIONAL RESPONSES ARE EXPECTED
ON ANY OF THE WATERSHEDS IN OUR REGION. OTHERWISE...WE ARE DRY AGAIN
THROUGH MUCH OF THE UPCOMING WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...BGM/SNYDER
NEAR TERM...HWJIV/BGM
SHORT TERM...SNYDER
LONG TERM...SNYDER
AVIATION...HWJIV/BGM
FIRE WEATHER...HWJIV
HYDROLOGY...HWJIV
FOR THE LATEST UPDATES...PLEASE VISIT OUR WEBPAGE AT
WWW.WEATHER.GOV/ALBANY
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
915 AM EST SUN NOV 17 2013
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE TO BUILD INTO THE REGION FROM THE
NORTHEAST THROUGH TONIGHT. A STRONG COLD FRONT WILL THEN MOVE
THROUGH LATE MONDAY FOLLOWED BY COLDER HIGH PRESSURE BUILDING FROM
THE NORTH THROUGH THE MIDDLE OF THE WEEK. ANOTHER COLD FRONT COULD
MOVE THROUGH SATURDAY WITH HIGH PRESSURE RETURNING FOR THE END OF
NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ISENTROPICALLY INDUCED SHOWER ACTIVITY HAS BEEN DIMINISHING OVER
LAST FOR THE PAST TWO HOURS. SHORT TERM GUIDANCE IS NOT OVERLY
EXCITED ABOUT THE PROSPECTS FOR MEASURABLE RAINFALL THROUGH EARLY
AFTERNOON ANYWHERE ACROSS SOUTHEAST SOUTH CAROLINA AND SOUTHEAST
GEORGIA...HOWEVER RAP ISENTROPIC FIELDS SHOW MODEST 295-305K
ISENTROPIC ASSENT GOING THROUGH THE DAY. WILL LOWER POPS OUT OF
THE LIKELY CATEGORY INTO THE MID-RANGE CHANCE CATEGORY ACROSS THE
SOUTH BASED ON CURRENT RADAR DATA. THERE ARE SOME SIGNALS THAT A
LOOSELY CONCENTRATED AREA OF SHOWERS COULD BRUSH THE CHARLESTON
METRO AREA BY EARLY AFTERNOON...BUT AGAIN...MODELS ARE NOT OVERLY
IMPRESSED. WILL SHOW 30-40 PERCENT POPS AREA WIDE TODAY...WITH
INCREASING POPS ACROSS THE NORTH AS MORE ORGANIZED SHOWER ACTIVITY
ATTEMPTS TO APPROACH THE SOUTH CAROLINA ZONES LATER THIS AFTERNOON
AS SHORTWAVE ENERGY APPROACHES.
EXTENSIVE CLOUD COVER WILL LIMIT HIGHS SOMEWHAT TODAY...ALTHOUGH
PRE-FRONTAL COMPRESSIONAL HEATING AND ONGOING WARM AIR ADVECTION
COULD COUNTERACT THE LACK OF STRONG INSOLATION. WILL MAINTAIN
HIGHS IN THE MID 70S FOR NOW.
THE REMAINDER OF THE FORECAST IS ON TRACK.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
TONIGHT...A SOUTH-SOUTHWEST FLOW AHEAD OF AN APPROACHING COLD
FRONT FROM THE NORTHWEST WILL KEEP DEEP LAYERED MOISTURE IN PLACE
ACROSS THE REGION. PRE-FRONTAL SHOWERS ARE EXPECTED TO OCCUR AND
THE FORECAST SHOWS A CHANCE OF SHOWERS FOR THE ENTIRE FORECAST
AREA. HAVE REMOVED THE MENTION OF THUNDERSTORMS DUE TO LIMITED
INSTABILITY BECAUSE OF NOCTURNAL COOLING. IT SHOULD BE A
RELATIVELY WARM NIGHT GIVEN THE SOUTH-SOUTHWEST FLOW AND EXTENSIVE
CLOUD COVER...WITH LOWS FORECAST IN THE MID 60S IN MOST AREAS.
MONDAY THROUGH WEDNESDAY...A COLD FRONT IS SLATED TO APPROACH
FROM THE WEST MONDAY MORNING AND THEN SLOWLY PUSH TOWARD THE COAST
DURING THE AFTERNOON...ALTHOUGH THERE IS STILL SOME UNCERTAINTY
REGARDING THE TIMING OF THIS FEATURE. OVERALL WE THINK THE BEST
RAIN CHANCES WILL COME IN THE MORNING WHEN THE DEEPEST MOISTURE
WILL BE IN PLACE...BUT THE NAM12 RE-FIRES SOME CONVECTION IN THE
AFTERNOON ALONG AND AHEAD OF A SLOWER-MOVING FRONT AS TEMPERATURES
WARM TO NEAR 80 DEGREES. THUS...WOULD NOT BE SURPRISED TO SEE A
FEW GUSTY THUNDERSTORMS DURING THE AFTERNOON IF THE FRONT IS
INDEED SLOWER TO PASS THROUGH. MUCH DRIER AND COOLER AIR WILL PUSH
IN FROM THE NORTH MONDAY NIGHT BEHIND THE FRONT...CONTINUING
THROUGH WEDNESDAY. THIS WILL LEAD TO BREEZY NORTH/NORTHEAST WINDS
TUESDAY AND WEDNESDAY...ESPECIALLY ALONG THE COAST.
LAKE WINDS...SMALL RISK FOR LOW-END ADVISORY CONDITIONS DEVELOPING
ON LAKE MOULTRIE LATE MONDAY NIGHT INTO EARLY TUESDAY AS STRONG HIGH
PRESSURE BUILDS IN FROM THE NORTH.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
COOL/DRY HIGH PRESSURE WILL PERSIST NORTH OF THE AREA THROUGH THE
MIDDLE OF THE WEEK BEFORE BREAKING DOWN LATE IN THE WEEK AS A COLD
FRONT APPROACHES. THERE IS NOW MUCH BETTER AGREEMENT BETWEEN THE GFS
AND ECMWF SHOWING THE FRONT PUSHING THROUGH SATURDAY WITH
COOLER/DRIER HIGH PRESSURE BUILDING BACK IN FOR THE END OF THE
WEEKEND. OTHERWISE...IT WILL BE BREEZY THROUGH MID WEEK DUE TO THE
TIGHT PRESSURE GRADIENT...WITH HIGHEST WINDS CLOSER TO THE COAST.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
GIVEN EXPANSIVE MID AND UPPER LEVELS CLOUDS...THE THREAT FOR FOG
HAS ENDED AT THE TERMINALS THIS MORNING.
KCHS...VFR CONDITIONS ARE EXPECTED TO PREVAIL TODAY...ALTHOUGH
THERE IS THE POTENTIAL FOR CEILINGS TO DROP TO MVFR LEVELS AT
TIMES. SCATTERED SHOWERS ARE EXPECTED TO DEVELOP THIS AFTERNOON
AND PERSIST INTO EARLY THIS EVENING AS A DISTURBANCE CROSSES THE
REGION...THUS HAVE INCLUDED VICINITY SHOWERS IN THE TAF/S FROM
18-02Z. MODELS ARE IN FAIRLY GOOD AGREEMENT INDICATING THE
POTENTIAL FOR IFR CEILINGS AND MVFR VISIBILITIES FROM ABOUT 02Z
THROUGH THE END OF THE FORECAST PERIOD AT 12Z MONDAY.
KSAV...STRATUS ACROSS SOUTHERN GEORGIA WILL LIFT NORTHWARD THIS
MORNING AND IS EXPECTED TO IMPACT THE TERMINAL FROM ABOUT 14-18Z.
DURING THIS TIME...THE TAF INDICATES PREVAILING MVFR CEILINGS WITH
TEMPORARY IFR CEILINGS FROM 14-16Z. THEN...CEILINGS SHOULD LIFT TO
LOW-END VFR LEVELS THROUGH THE REMAINDER OF THE DAY...ALTHOUGH
THEY COULD DROP TO MVFR LEVELS AT TIMES. SCATTERED SHOWERS ARE
EXPECTED TO DEVELOP THIS AFTERNOON AND PERSIST INTO EARLY THIS
EVENING AS A DISTURBANCE CROSSES THE REGION...THUS HAVE INCLUDED
VICINITY SHOWERS IN THE TAF/S FROM 18-02Z. MODELS ARE IN FAIRLY
GOOD AGREEMENT INDICATING THE POTENTIAL FOR IFR CEILINGS AND MVFR
VISIBILITIES FROM ABOUT 02Z THROUGH THE END OF THE FORECAST PERIOD
AT 12Z MONDAY.
EXTENDED AVIATION OUTLOOK...MVFR...POSSIBLY IFR...CONDITIONS MON
ALONG AND AHEAD OF A COLD FRONT. OTHERWISE...MAINLY VFR THROUGH
FRIDAY...ALTHOUGH BREEZY/GUSTY CONDITIONS ARE EXPECTED
TUESDAY/WEDNESDAY AND POSSIBLY THURSDAY.
&&
.MARINE...
TODAY...A COASTAL TROUGH WILL DISSIPATE EAST OF THE WATERS...ALLOWING
A RETURN FLOW TO DEVELOP ALONG THE PERIPHERY OF HIGH PRESSURE
NORTHEAST OF THE REGION. THIS WILL CAUSE WINDS TO GRADUALLY VEER
SOUTHEAST OR SOUTH THROUGH THE DAY. WIND SPEEDS WILL GENERALLY BE
AROUND 10 KT OR LESS DUE TO THE LACK ANY SIGNIFICANT PRESSURE
GRADIENT. SEAS WILL REMAIN IN THE 2-4 FT RANGE.
TONIGHT...A SOUTH-SOUTHWEST FLOW WILL STRENGTHEN TO AS MUCH AS
10-15 KT IN ADVANCE OF AN APPROACHING COLD FRONT FROM THE
NORTHWEST. SEAS WILL BUILD BY ABOUT A FOOT OR SO AS A RESULT.
PERHAPS THE BIGGEST CONCERN TONIGHT IS FOR THE POTENTIAL FOR SEA
FOG TO FORM AS DEWPOINTS SURGE IN THE UPPER 60S ON THE
STRENGTHENING SOUTHERLY FLOW. GIVEN CONSIDERABLY COOLER SEA SURFACE
TEMPERATURES...THIS WILL RESULT IN CONDITIONS FAVORABLE FOR SEA
FOG TO FORM OR ADVECT IN FROM THE SOUTH TONIGHT AND COULD REDUCE
VISIBILITIES ENOUGH TO WARRANT A DENSE FOG ADVISORY FOR PORTIONS
OF THE NEAR SHORE COASTAL WATERS AND CHARLESTON HARBOR.
MONDAY THROUGH FRIDAY...A COLD FRONT WILL PUSH THROUGH LATE MONDAY
WITH WINDS/SEAS INCREASING GREATLY MONDAY NIGHT FROM THE NORTH AS
STRONG HIGH PRESSURE BUILDS INTO THE OHIO VALLEY. SOLID SMALL CRAFT
ADVISORY CONDITIONS ARE ANTICIPATED FOR ALL WATERS INTO THURSDAY
WITH THE POTENTIAL FOR GALE FORCE WINDS...MAINLY BEYOND 20 NM FROM
SHORE.
INCREASING LOW-LEVEL MOISTURE ATOP THE RELATIVELY COOL NEARSHORE
WATERS COULD PRODUCE SOME SEA FOG MONDAY UNTIL THE FRONT PUSHES
THROUGH.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
621 AM EST SUN NOV 17 2013
.SYNOPSIS...
HIGH PRESSURE CENTERED OFF THE MID-ATLANTIC COAST WILL DIRECT AN
ONSHORE FLOW INTO THE FORECAST AREA AHEAD OF AN APPROACHING COLD
FRONT. THE FRONT WILL MOVE THROUGH THE AREA EARLY MONDAY. COLD
HIGH PRESSURE WILL FOLLOW THE FRONT AND DOMINATE THROUGH THE
MIDDLE OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
DENSE FOG COVERED MUCH OF THE FORECAST AREA EARLY THIS MORNING.
SHALLOW LOW-LEVEL MOISTURE AND LIGHT WIND HELPED CAUSE THE FOG.
BASED ON THE HRRR GUIDANCE EXPECT IMPROVING VISIBILITIES BEGINNING
AROUND 1000 AM. WE HAVE POSTED A DENSE FOG ADVISORY.
MOISTURE WILL BECOME DEEPER LATER TODAY WITH A MOIST SOUTHEAST TO
SOUTH FLOW ASSOCIATED WITH THE OFFSHORE HIGH PLUS AN APPROACHING
MID-LEVEL SHORTWAVE TROUGH. THE SHOWER CHANCE SHOULD INCREASE
DURING THE AFTERNOON. THE GUIDANCE CONSENSUS SUPPORTS POPS OF 40
TO 60 PERCENT. WE LEANED TOWARD THE GFS AND ECMWF MOS FOR THE
TEMPERATURE FORECAST. THE NAM MOS MAY BE TOO WARM BECAUSE OF THE
MORNING FOG AND SOME CLOUDINESS CONTINUING FOR MUCH OF THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
THE COLD FRONT WILL CONTINUE TO APPROACH TONIGHT. THE NAM AND GFS
INDICATE DEEP MOISTURE WITH PRECIPITABLE WATER INCREASING TO NEAR
1.8 OF AN INCH. USED THE HIGHER POP GUIDANCE. AN AVERAGE OF THE
GFS AND NAM PLUS SREF MEAN SUPPORTS TOTAL RAINFALL AROUND ONE-
QUARTER OF AN INCH. DESPITE THE HIGH PRECIPITABLE WATER THIS
RELATIVELY LIGHT AMOUNT MAY BE CORRECT BECAUSE OF WEAK LIFT. THERE
MAY BE ENOUGH INSTABILITY FOR THUNDERSTORMS. THE NAM INDICATES
A SHOWALTER INDEX AROUND -1 TONIGHT. ITS LOWEST SURFACE-BASED LI
IS AROUND ZERO. THE MODEL TREND HAS BEEN DIMINISHING INSTABILITY.
THE WEAK INSTABILITY APPEARS REASONABLE BECAUSE MOST OF THE
UPPER-LEVEL LIFT SHOULD STAY WELL NORTH OF THE FORECAST AREA.
SHEAR WILL BE STRONG WITH H85 WINDS NEAR 30 KNOTS BUT WITH A LACK
OF SIGNIFICANT INSTABILITY THE THREAT OF SEVERE THUNDERSTORMS IS
LOW. THE NAM AND GFS ARE CONSISTENT SHOWING DRYING BEGINNING BY
MIDDAY MONDAY BEHIND THE FRONT.
BELIEVE THE WARMER TEMPERATURE GUIDANCE IS BETTER TODAY BECAUSE OF
THE WARM AIR MASS AHEAD OF THE FRONT. CLOUDINESS AND MIXING SHOULD
HOLD UP TEMPERATURES TONIGHT. THE TEMPERATURE GUIDANCE IS LIKELY
TOO COOL. WE WILL GET OFF TO A RELATIVELY WARM START MONDAY AND
THE COOLER AIR WILL BE LAGGING BEHIND THE FRONT. IT SHOULD BE
ANOTHER VERY WARM DAY. USED THE WARMER TEMPERATURE GUIDANCE.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE MEDIUM-RANGE MODELS ARE IN GOOD AGREEMENT INDICATING DRY
RIDGING DOMINATING TUESDAY THROUGH WEDNESDAY. MOISTURE MAY BEGIN TO
INCREASE THURSDAY WITH AN ONSHORE FLOW AND THE MOISTURE MAY BE
DEEP BY SATURDAY ASSOCIATED WITH A FRONTAL SYSTEM. THE ECMWF WAS
SLOWER WITH THE TIMING OF THE FRONT. AN AVERAGE OF THE
GFS...ECMWF...AND EKD MOS SUPPORTED CHANCE POPS SATURDAY.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
WEAK WEDGE CONTINUES OVER THE AREA EARLY THIS MORNING. CONDITIONS
DETERIORATING TO IFR/LIFR LEVELS ACROSS MUCH OF THE AREA. MODELS
STILL SUGGESTING IFR/LIFR FOG WILL PERSIST UNTIL AROUND 14Z. COULD
SEE SOME VARIABILITY IN CONDITIONS AMONG THE TAF SITES...WITH
CLOUDS POSSIBLY KEEPING AGS/DNL AT VFR EARLY THIS MORNING. SHOULD
SEE CIG/VSBY IMPROVEMENT TO MVFR OR VFR 15Z-17Z. CHANCE FOR
SHOWERS LATER THIS AFTERNOON WILL INCREASE FOR TONIGHT AS A COLD
FRONT APPROACHES FROM THE WEST. WILL MENTION MVFR CIGS/VSBYS WITH
SHOWERS AFTER 06Z MONDAY...BUT LOWER CONDITIONS MAY BE POSSIBLE
AS THE FRONT GETS CLOSER.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS CAN BE EXPECTED EARLY
MONDAY MORNING AHEAD OF AN APPROACHING COLD FRONT. THE COLD FRONT IS
FORECAST TO CROSS THE AREA BY LATE MONDAY MORNING. BREEZY CONDITIONS
POSSIBLE TUESDAY AND WEDNESDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR SCZ015-016-
018-020>022-025>031-035>038-041.
GA...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR GAZ040-
063>065-077.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
521 AM EST SUN NOV 17 2013
.SYNOPSIS...
HIGH PRESSURE CENTERED OFF THE MID-ATLANTIC COAST WILL DIRECT AN
ONSHORE FLOW INTO THE FORECAST AREA AHEAD OF AN APPROACHING COLD
FRONT. THE FRONT WILL MOVE THROUGH THE AREA EARLY MONDAY. COLD
HIGH PRESSURE WILL FOLLOW THE FRONT AND DOMINATE THROUGH THE
MIDDLE OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
DENSE FOG COVERED MUCH OF THE FORECAST AREA EARLY THIS MORNING.
SHALLOW LOW-LEVEL MOISTURE AND LIGHT WIND HELPED CAUSE THE FOG.
BASED ON THE HRRR GUIDANCE EXPECT IMPROVING VISIBILITIES BEGINNING
AROUND 1000 AM. WE HAVE POSTED A DENSE FOG ADVISORY.
MOISTURE WILL BECOME DEEPER LATER TODAY WITH A MOIST SOUTHEAST TO
SOUTH FLOW ASSOCIATED WITH THE OFFSHORE HIGH PLUS AN APPROACHING
MID-LEVEL SHORTWAVE TROUGH. THE SHOWER CHANCE SHOULD INCREASE
DURING THE AFTERNOON. THE GUIDANCE CONSENSUS SUPPORTS POPS OF 40
TO 60 PERCENT. WE LEANED TOWARD THE GFS AND ECMWF MOS FOR THE
TEMPERATURE FORECAST. THE NAM MOS MAY BE TOO WARM BECAUSE OF THE
MORNING FOG AND SOME CLOUDINESS CONTINUING FOR MUCH OF THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
THE COLD FRONT WILL CONTINUE TO APPROACH TONIGHT. THE NAM AND GFS
INDICATE DEEP MOISTURE WITH PRECIPITABLE WATER INCREASING TO NEAR
1.8 OF AN INCH. USED THE HIGHER POP GUIDANCE. AN AVERAGE OF THE
GFS AND NAM PLUS SREF MEAN SUPPORTS TOTAL RAINFALL AROUND ONE-
QUARTER OF AN INCH. DESPITE THE HIGH PRECIPITABLE WATER THIS
RELATIVELY LIGHT AMOUNT MAY BE CORRECT BECAUSE OF WEAK LIFT. THERE
MAY BE ENOUGH INSTABILITY FOR THUNDERSTORMS. THE NAM INDICATES
A SHOWALTER INDEX AROUND -1 TONIGHT. ITS LOWEST SURFACE-BASED LI
IS AROUND ZERO. THE MODEL TREND HAS BEEN DIMINISHING INSTABILITY.
THE WEAK INSTABILITY APPEARS REASONABLE BECAUSE MOST OF THE
UPPER-LEVEL LIFT SHOULD STAY WELL NORTH OF THE FORECAST AREA.
SHEAR WILL BE STRONG WITH H85 WINDS NEAR 30 KNOTS BUT WITH A LACK
OF SIGNIFICANT INSTABILITY THE THREAT OF SEVERE THUNDERSTORMS IS
LOW. THE NAM AND GFS ARE CONSISTENT SHOWING DRYING BEGINNING BY
MIDDAY MONDAY BEHIND THE FRONT.
BELIEVE THE WARMER TEMPERATURE GUIDANCE IS BETTER TODAY BECAUSE OF
THE WARM AIR MASS AHEAD OF THE FRONT. CLOUDINESS AND MIXING SHOULD
HOLD UP TEMPERATURES TONIGHT. THE TEMPERATURE GUIDANCE IS LIKELY
TOO COOL. WE WILL GET OFF TO A RELATIVELY WARM START MONDAY AND
THE COOLER AIR WILL BE LAGGING BEHIND THE FRONT. IT SHOULD BE
ANOTHER VERY WARM DAY. USED THE WARMER TEMPERATURE GUIDANCE.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE MEDIUM-RANGE MODELS ARE IN GOOD AGREEMENT INDICATING DRY
RIDGING DOMINATING TUESDAY THROUGH WEDNESDAY. MOISTURE MAY BEGIN TO
INCREASE THURSDAY WITH AN ONSHORE FLOW AND THE MOISTURE MAY BE
DEEP BY SATURDAY ASSOCIATED WITH A FRONTAL SYSTEM. THE ECMWF WAS
SLOWER WITH THE TIMING OF THE FRONT. AN AVERAGE OF THE
GFS...ECMWF...AND EKD MOS SUPPORTED CHANCE POPS SATURDAY.
&&
.AVIATION /11Z SUNDAY THROUGH THURSDAY/... WEAK WEDGE CONTINUES
OVER THE AREA EARLY THIS MORNING. CONDITIONS DETERIORATING TO
IFR/LIFR LEVELS ACROSS MUCH OF THE AREA. MODELS STILL SUGGESTING
IFR/LIFR FOG WILL PERSIST UNTIL AROUND 14Z. COULD BE SOME
VARIABILITY IN CONDITIONS AMONG THE TAF SITES...WITH CLOUDS
POSSIBLY KEEPING AGS/DNL AT VFR EARLY THIS MORNING. WATER VAPOR
SATELLITE IMAGE INDICATING HIGH LEVEL MOISTURE STREAMING ACROSS
THE REGION. SHOULD SEE CIG/VSBY IMPROVEMENT TO MVFR OR VFR 15Z-
17Z. CHANCE FOR SHOWERS LATER THIS AFTERNOON WILL INCREASE FOR
TONIGHT AS A COLD FRONT APPROACHES FROM THE WEST.
EXTENDED AVIATION OUTLOOK...MODERATE TO HIGH CONFIDENCE IN
RESTRICTIONS LATE SUNDAY NIGHT INTO MONDAY MORNING AHEAD OF AN
APPROACHING COLD FRONT. THE COLD FRONT IS FORECAST TO CROSS THE AREA
MONDAY MORNING. BREEZY CONDITIONS POSSIBLE TUESDAY AND WEDNESDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR SCZ015-016-
018-020>022-025>031-035>038-041.
GA...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR GAZ040-
063>065-077.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
514 AM EST SUN NOV 17 2013
.SYNOPSIS...
HIGH PRESSURE CENTERED OFF THE MID-ATLANTIC COAST WILL DIRECT AN
ONSHORE FLOW INTO THE FORECAST AREA AHEAD OF AN APPROACHING COLD
FRONT. THE FRONT WILL MOVE THROUGH THE AREA EARLY MONDAY. COLD
HIGH PRESSURE WILL FOLLOW THE FRONT AND DOMINATE THROUGH THE
MIDDLE OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
DENSE FOG COVERED MUCH OF THE FORECAST AREA EARLY THIS MORNING.
SHALLOW LOW-LEVEL MOISTURE AND LIGHT WIND HELPED CAUSE THE FOG.
BASED ON THE HRRR GUIDANCE EXPECT IMPROVING VISIBILITIES BEGINNING
AROUND 1000 AM. WE HAVE POSTED A DENSE FOG ADVISORY.
MOISTURE WILL BECOME DEEPER LATER TODAY WITH A MOIST SOUTHEAST TO
SOUTH FLOW ASSOCIATED WITH THE OFFSHORE HIGH PLUS AN APPROACHING
MID-LEVEL SHORTWAVE TROUGH. THE SHOWER CHANCE SHOULD INCREASE
DURING THE AFTERNOON. THE GUIDANCE CONSENSUS SUPPORTS POPS OF 40
TO 60 PERCENT. WE LEANED TOWARD THE GFS AND ECMWF MOS FOR THE
TEMPERATURE FORECAST. THE NAM MOS MAY BE TOO WARM BECAUSE OF THE
MORNING FOG AND SOME CLOUDINESS CONTINUING FOR MUCH OF THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
THE COLD FRONT WILL CONTINUE TO APPROACH TONIGHT. THE NAM AND GFS
INDICATE DEEP MOISTURE WITH PRECIPITABLE WATER INCREASING TO NEAR
1.8 OF AN INCH. USED THE HIGHER POP GUIDANCE. AN AVERAGE OF THE
GFS AND NAM PLUS SREF MEAN SUPPORTS TOTAL RAINFALL AROUND ONE-
QUARTER OF AN INCH. DESPITE THE HIGH PRECIPITABLE WATER THIS
RELATIVELY LIGHT AMOUNT MAY BE CORRECT BECAUSE OF WEAK LIFT. THERE
MAY BE ENOUGH INSTABILITY FOR THUNDERSTORMS. THE NAM INDICATES
A SHOWALTER INDEX AROUND -1 TONIGHT. ITS LOWEST SURFACE-BASED LI
IS AROUND ZERO. THE MODEL TREND HAS BEEN DIMINISHING INSTABILITY.
THE WEAK INSTABILITY APPEARS REASONABLE BECAUSE MOST OF THE
UPPER-LEVEL LIFT SHOULD STAY WELL NORTH OF THE FORECAST AREA.
SHEAR WILL BE STRONG WITH H85 WINDS NEAR 30 KNOTS BUT WITH A LACK
OF SIGNIFICANT INSTABILITY THE THREAT OF SEVERE THUNDERSTORMS IS
LOW. THE NAM AND GFS ARE CONSISTENT SHOWING DRYING BEGINNING BY
MIDDAY MONDAY BEHIND THE FRONT.
BELIEVE THE WARMER TEMPERATURE GUIDANCE IS BETTER TODAY BECAUSE OF
THE WARM AIR MASS AHEAD OF THE FRONT. CLOUDINESS AND MIXING SHOULD
HOLD UP TEMPERATURES TONIGHT. THE TEMPERATURE GUIDANCE IS LIKELY
TOO COOL. WE WILL GET OFF TO A RELATIVELY WARM START MONDAY AND
THE COOLER AIR WILL BE LAGGING BEHIND THE FRONT. IT SHOULD BE
ANOTHER VERY WARM DAY. USED THE WARMER TEMPERATURE GUIDANCE.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE MEDIUM-RANGE MODELS ARE IN GOOD AGREEMENT INDICATING DRY
RIDGING DOMINATING TUESDAY THROUGH WEDNESDAY. MOISTURE MAY BEGIN TO
INCREASE THURSDAY WITH AN ONSHORE FLOW AND THE MOISTURE MAY BE
DEEP BY SATURDAY ASSOCIATED WITH A FRONTAL SYSTEM. THE ECMWF WAS
SLOWER WITH THE TIMING OF THE FRONT. AN AVERAGE OF THE
GFS...ECMWF...AND EKD MOS SUPPORTED CHANCE POPS SATURDAY.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
WEAK WEDGE CONTINUES OVER THE AREA EARLY THIS MORNING. CONFIDENCE
STILL HIGH FOR LIFR/IFR CONDITIONS AT ALL TERMINALS. SHOULD SEE
CIG/VSBY IMPROVEMENT TO MVFR OR VFR 16Z-18Z. CHANCE FOR SHOWERS
LATER THIS AFTERNOON WILL INCREASE FOR TONIGHT AS A COLD FRONT
APPROACHES FROM THE WEST.
EXTENDED AVIATION OUTLOOK...MODERATE TO HIGH CONFIDENCE IN
RESTRICTIONS SUNDAY NIGHT INTO MONDAY MORNING AHEAD OF AN
APPROACHING COLD FRONT. THE COLD FRONT IS FORECAST TO CROSS
THE AREA MONDAY MORNING. BREEZY CONDITIONS POSSIBLE TUESDAY AND
WEDNESDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR SCZ015-016-
018-020>022-025>031-035>038-041.
GA...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR GAZ040-
063>065-077.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
931 AM EST SUN NOV 17 2013
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 355 AM EST SUN NOV 17 2013
SEVERE WEATHER IS EXPECTED TODAY WITH MUCH OF CENTRAL
INDIANA BEING IN A HIGH RISK FOR SEVERE WEATHER AS A DYNAMIC AND
STRENGTHENING LOW PRESSURE SYSTEM SWINGS OUT OF THE PLAINS AND
THROUGH THE GREAT LAKES. BY TONIGHT THE COLD FRONT ASSOCIATED WITH
THIS SYSTEM SHOULD BE THROUGH THE AREA AND DRY AIR WILL USHER IN
BEHIND IT. HIGH PRESSURE WILL BUILD IN AND BRING DRY WEATHER THROUGH
MID WEEK. A RAINY PATTERN WILL RETURN FOR THE END OF THE WEEK AND A
COLD FRONT WILL BRING COLD TEMPERATURES IN FOR NEXT WEEKEND.
&&
.NEAR TERM /UPDATE FOR TODAY/...
ISSUED AT 927 AM EST SUN NOV 17 2013
NO SIGNIFICANT CHANGES MADE TO FORECASTS. GUSTS HAVE BEGUN.
INTERMITTENT SUNSHINE WILL ADD TO INSTABILITY. STORM PREDICTION
CENTER HAD EXPANDED HIGH RISK TO NEARLY ALL OF INDIANA BUT NO REAL
CHANGE FOR CENTRAL INDIANA OTHER THAN ADDING EASTERN COUNTIES.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 355 AM EST SUN NOV 17 2013
MODELS SHOW THE COLD FRONT BEING EAST AND SOUTH OF THE FORECAST AREA
BY 0Z TONIGHT...BUT HAVE HELD ONTO POPS IN THE FAR EAST AND SOUTH
FOR THE FIRST FEW HOURS FOR COLLABORATION PURPOSES. BY 3Z HOWEVER
HAVE GONE DRY. AFTER THAT HIGH PRESSURE BUILDS IN FOR THE REMAINDER
OF THE SHORT TERM AND SHOULD SEE MOSTLY CLEAR SKIES AND SLIGHTLY
BELOW NORMAL TEMPERATURES.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 147 AM EST SUN NOV 17 2013
ECMWF AND GFS SHOW DRY WEATHER PERSISTING ACROSS CENTRAL INDIANA
ON WEDNESDAY AS HIGH PRESSURE DEPARTS THE AREA. HOWEVER A WET AND
ACTIVE END TO THE NEXT WORK WEEK LOOKS IN STORE AS SEVERAL WEATHER
SYSTEMS LOOKS TO PUSH ACROSS THE REGION STARTING ON THURSDAY AND
CONTINUING THROUGH SATURDAY. SEVERAL UPPER LEVEL WEATHER SYSTEMS
WITH A MOIST SOUTHWEST FLOW IN PLACE ALOFT WILL PROVIDE SEVERAL
CHANCES AT SHOWERS STARTING ON THURSDAY AND AGAIN ON FRIDAY AS A
WARM FRONTAL BOUNDARY PASSES ACROSS THE OHIO VALLEY.
THE GFS AND ECMWF SHOW A STRONGER COLD FRONT PUSHING ACROSS THE
REGION ON FRIDAY NIGHT...GIVING US ANOTHER SHOT AT PRECIP...ALONG
WITH MUCH COLDER AIR IN THE WAKE OF THE FRONT FOR NEXT WEEKEND.
&&
.AVIATION /DISCUSSION FOR THE 171200Z TAFS/...
ISSUED AT 511 AM EST SUN NOV 17 2013
POOR FLYING CONDITIONS ARE EXPECTED THIS TAF PERIOD AS MVFR TO
IFR CONDITIONS WILL BE EXPECTED FOR THE NEXT 12 HOURS ALONG WITH
GUSTY SOUTH TO SOUTHWEST WINDS.
A STRONG LOW PRESSURE SYSTEM IS EXPECTED TO PUSH ACROSS INDIANA
TODAY. HRRR REFLECTIVITY SHOWS AN EXPECTED BAND OF TSRA TO DEVELOP
AND PUSH ACROSS INDIANA ALONG OR JUST SLIGHTLY AHEAD OF THE COLD
FRONT THIS AFTERNOON. IN THE MEANTIME...RADAR CONTINUES TO SHOW SCT
SHRA ACROSS CENTRAL INDIANA AS WARM AND MOIST AIR ARRIVES IN THE
AREA ON SW WINDS. FORECAST SOUNDINGS SHOW GOOD LOWER LEVEL
MOISTURE THIS MORNING...INDICATING THE MVFR TO IFR CIGS...FOLLOWED
BY STEEP LAPSE RATES ALOFT LATER THIS AFTERNOON AS THE COLD FRONT
APPROACHES AND PASSES. STRONG PRESSURE GRADIENT REMAINS IN PLACE
AS A STRONG LLJ OF 50 KNTS IS EXPECTED TO PASS AHEAD OF THE COLD
FRONT...THUS WILL CONTINUE TO INCLUDE GUSTY WINDS IN THE TAFS.
IN THE WAKE OF THE FRONT...FORECAST SOUNDINGS SHOW STRONG
SUBSIDENCE AND DRYING AND A RETURN TO VFR CONDITIONS BY LATE THIS EVENING.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 9 PM EST THIS EVENING FOR INZ021-028>031-
035>049-051>057-060>065-067>072.
&&
$$
SYNOPSIS...CP
NEAR TERM...TUCEK
SHORT TERM...CP
LONG TERM....PUMA
AVIATION...JP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
930 AM EST SUN NOV 17 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 355 AM EST SUN NOV 17 2013
SEVERE WEATHER IS EXPECTED TODAY WITH MUCH OF CENTRAL
INDIANA BEING IN A HIGH RISK FOR SEVERE WEATHER AS A DYNAMIC AND
STRENGTHENING LOW PRESSURE SYSTEM SWINGS OUT OF THE PLAINS AND
THROUGH THE GREAT LAKES. BY TONIGHT THE COLD FRONT ASSOCIATED WITH
THIS SYSTEM SHOULD BE THROUGH THE AREA AND DRY AIR WILL USHER IN
BEHIND IT. HIGH PRESSURE WILL BUILD IN AND BRING DRY WEATHER THROUGH
MID WEEK. A RAINY PATTERN WILL RETURN FOR THE END OF THE WEEK AND A
COLD FRONT WILL BRING COLD TEMPERATURES IN FOR NEXT WEEKEND.
&&
.NEAR TERM /TODAY/...
ISSUED AT 355 AM EST SUN NOV 17 2013
THE TRIGGER HAS BEEN PULLED ON THE HIGH RISK WITH CENTRAL INDIANA
BEING UNDER THE GUN FOR SEVERE WEATHER TODAY. SPC HAS PLACED MUCH OF
THE AREA IN A 30 PERCENT HATCHED RISK FOR TORNADOES...MEANING THERE
IS A 30 PERCENT CHANCE OF AN EF2 OR STRONGER TORNADO WITHIN 25 MILES
OF ANY GIVEN POINT. THE SYSTEM IS EXTREMELY DYNAMIC WITH THE UPPER
TROUGH BECOMING NEGATIVELY TILTED AS IT SWINGS OUT OF ITS CURRENT
POSITION OVER THE INTERMOUNTAIN WEST AND INTO THE UPPER MIDWEST BY
0Z. DEW POINTS ACROSS THE AREA ARE ALREADY IN THE UPPER 50S TO
AROUND 60 IN THE SOUTH WITH LOW 60S UPSTREAM. GUIDANCE HIGHS FOR THE
DAY HAVE COME BACK DOWN A BIT GIVEN CLOUD COVER SHOULD BE IN PLACE
FOR THE ENTIRE DAY BUT STILL YIELDS HIGHS ACROSS THE AREA IN THE
UPPER 60S TO LOWER 70S. THUS SURFACE BASED CAPES THE GFS ARE RUNNING
IN THE LOW TO MIDDLE HUNDREDS FOR MIDDAY AND HIGHER IN THE NAM WITH
MIXED LAYER CAPES IN THE LOW HUNDREDS. WHILE THESE INSTABILITY
NUMBERS ARE NOT HIGH...THEY SHOULD BE SUFFICIENT GIVEN SIGNIFICANT
SHEAR WITH LOW LEVEL...MID LEVEL AND UPPER LEVEL JET MAXES GOING
THROUGH LATER TODAY. LONG CURVED HODOGRAPHS AND 0-1 KM HELICITY
VALUES OF 300-500 SHOW THE SIGNIFICANT POTENTIAL FOR SUPERCELL AND
TORNADO FORMATION.
ONE POSSIBLE WRENCH IN TODAY/S EVENT FOR THIS FORECAST AREA IS THE
OVERNIGHT CONVECTION. A BIT OF CONCERN THAT THIS COULD LEAVE A
STABLE RAIN COOLED AIRMASS OVER THE AREA WITH A BOUNDARY ACROSS THE
SOUTHERN FORECAST AREA OR JUST SOUTH OF THERE THAT COULD IN EFFECT
INHIBIT DEVELOPMENT OVER MUCH OF THE FORECAST AREA DURING THE LATE
MORNING/EARLY AFTERNOON...THUS PREVENTING SUPERCELL DEVELOPMENT.
SHOULD THIS OCCUR...GREAT POTENTIAL WILL STILL BE IN PLACE FOR
SIGNIFICANT DAMAGING WINDS AND SPIN UP TORNADOES WITH THE SQUALL
LINE THAT SHOULD FORM AHEAD OF THE COLD FRONT BY LATE
MORNING/EARLY AFTERNOON ACROSS CENTRAL ILLINOIS.
THE RAPID REFRESH BRINGS THE DEVELOPING SQUALL LINE INTO THE
NORTHWEST COUNTIES AROUND 19Z. THIS AGREES WITH SREF TIMING THAT
BRINGS THE HIGHEST OMEGA THROUGH THE CENTRAL FORECAST AREA AROUND
21Z AND SWINGS THE FRONT AND ASSOCIATED UPWARD MOTION EAST OF THE
AREA BY 0Z AND STUCK WITH THIS TIMING FOR HIGHEST POPS.
ON NON-THUNDERSTORM WIND POTENTIAL...THE LOW PRESSURE SYSTEM WILL
DEEPEN SIGNIFICANTLY AS IT TRAVERSES THE UPPER MIDWEST AND THIS
COULD PRODUCE SOME STRONG WINDS JUST AHEAD OF OR MORE LIKELY JUST
BEHIND THE COLD FRONT. THINK THE STRONGEST OF THESE WINDS WILL STAY
NORTH OF THE FORECAST AREA CLOSER TO THE TRACK OF THE LOW AND THE
GREATEST PRESSURE CHANGES...HOWEVER...WIND ADVISORY STRENGTH GUST OF
50 MPH STILL LOOK LIKE A GOOD POSSIBILITY AND THUS CONTINUED WITH
WIND ADVISORY FOR THE AREA. THINK THE NORTHERN COUNTIES COULD FLIRT
WITH HIGH WIND WARNING CRITERIA...BUT AT THIS POINT THINK THEY WILL
STAY IN HIGH END ADVISORY TERRITORY.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 355 AM EST SUN NOV 17 2013
MODELS SHOW THE COLD FRONT BEING EAST AND SOUTH OF THE FORECAST AREA
BY 0Z TONIGHT...BUT HAVE HELD ONTO POPS IN THE FAR EAST AND SOUTH
FOR THE FIRST FEW HOURS FOR COLLABORATION PURPOSES. BY 3Z HOWEVER
HAVE GONE DRY. AFTER THAT HIGH PRESSURE BUILDS IN FOR THE REMAINDER
OF THE SHORT TERM AND SHOULD SEE MOSTLY CLEAR SKIES AND SLIGHTLY
BELOW NORMAL TEMPERATURES.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 147 AM EST SUN NOV 17 2013
ECMWF AND GFS SHOW DRY WEATHER PERSISTING ACROSS CENTRAL INDIANA
ON WEDNESDAY AS HIGH PRESSURE DEPARTS THE AREA. HOWEVER A WET AND
ACTIVE END TO THE NEXT WORK WEEK LOOKS IN STORE AS SEVERAL WEATHER
SYSTEMS LOOKS TO PUSH ACROSS THE REGION STARTING ON THURSDAY AND
CONTINUING THROUGH SATURDAY. SEVERAL UPPER LEVEL WEATHER SYSTEMS
WITH A MOIST SOUTHWEST FLOW IN PLACE ALOFT WILL PROVIDE SEVERAL
CHANCES AT SHOWERS STARTING ON THURSDAY AND AGAIN ON FRIDAY AS A
WARM FRONTAL BOUNDARY PASSES ACROSS THE OHIO VALLEY.
THE GFS AND ECMWF SHOW A STRONGER COLD FRONT PUSHING ACROSS THE
REGION ON FRIDAY NIGHT...GIVING US ANOTHER SHOT AT PRECIP...ALONG
WITH MUCH COLDER AIR IN THE WAKE OF THE FRONT FOR NEXT WEEKEND.
&&
.AVIATION /DISCUSSION FOR THE 171500Z IND TAF UPDATE/...
ISSUED AT 930 AM EST SUN NOV 17 2013
INCREASED WINDS TO 16 KNOTS WITH GUSTS TO 28 KNOTS AS THE
ATMOSPHERIC MIXING HAS BEGUN. ALSO...KEPT MVFR CEILINGS AND VCSH
WITH RADAR SHOWING SCATTERED WEAK SHOWER ACTIVITY IN THE VICINITY.
PREVIOUS DISCUSSION FOLLOWS...
POOR FLYING CONDITIONS ARE EXPECTED THIS TAF PERIOD AS MVFR TO
IFR CONDITIONS WILL BE EXPECTED FOR THE NEXT 12 HOURS ALONG WITH
GUSTY SOUTH TO SOUTHWEST WINDS.
A STRONG LOW PRESSURE SYSTEM IS EXPECTED TO PUSH ACROSS INDIANA
TODAY. HRRR REFLECTIVITY SHOWS AN EXPECTED BAND OF TSRA TO DEVELOP
AND PUSH ACROSS INDIANA ALONG OR JUST SLIGHTLY AHEAD OF THE COLD
FRONT THIS AFTERNOON. IN THE MEANTIME...RADAR CONTINUES TO SHOW SCT
SHRA ACROSS CENTRAL INDIANA AS WARM AND MOIST AIR ARRIVES IN THE
AREA ON SW WINDS. FORECAST SOUNDINGS SHOW GOOD LOWER LEVEL
MOISTURE THIS MORNING...INDICATING THE MVFR TO IFR CIGS...FOLLOWED
BY STEEP LAPSE RATES ALOFT LATER THIS AFTERNOON AS THE COLD FRONT
APPROACHES AND PASSES. STRONG PRESSURE GRADIENT REMAINS IN PLACE
AS A STRONG LLJ OF 50 KNTS IS EXPECTED TO PASS AHEAD OF THE COLD
FRONT...THUS WILL CONTINUE TO INCLUDE GUSTY WINDS IN THE TAFS.
IN THE WAKE OF THE FRONT...FORECAST SOUNDINGS SHOW STRONG SUBSIDENCE
AND DRYING AND A RETURN TO VFR CONDITIONS BY LATE THIS EVENING.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM NOON TODAY TO 9 PM EST THIS EVENING FOR
INZ021-028>031-035>049-051>057-060>065-067>072.
&&
$$
SYNOPSIS...CP
NEAR TERM...CP
SHORT TERM...CP
LONG TERM....PUMA
AVIATION...JP/MK
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
523 AM EST SUN NOV 17 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 355 AM EST SUN NOV 17 2013
SEVERE WEATHER IS EXPECTED TODAY WITH MUCH OF CENTRAL
INDIANA BEING IN A HIGH RISK FOR SEVERE WEATHER AS A DYNAMIC AND
STRENGTHENING LOW PRESSURE SYSTEM SWINGS OUT OF THE PLAINS AND
THROUGH THE GREAT LAKES. BY TONIGHT THE COLD FRONT ASSOCIATED WITH
THIS SYSTEM SHOULD BE THROUGH THE AREA AND DRY AIR WILL USHER IN
BEHIND IT. HIGH PRESSURE WILL BUILD IN AND BRING DRY WEATHER THROUGH
MID WEEK. A RAINY PATTERN WILL RETURN FOR THE END OF THE WEEK AND A
COLD FRONT WILL BRING COLD TEMPERATURES IN FOR NEXT WEEKEND.
&&
.NEAR TERM /TODAY/...
ISSUED AT 355 AM EST SUN NOV 17 2013
THE TRIGGER HAS BEEN PULLED ON THE HIGH RISK WITH CENTRAL INDIANA
BEING UNDER THE GUN FOR SEVERE WEATHER TODAY. SPC HAS PLACED MUCH OF
THE AREA IN A 30 PERCENT HATCHED RISK FOR TORNADOES...MEANING THERE
IS A 30 PERCENT CHANCE OF AN EF2 OR STRONGER TORNADO WITHIN 25 MILES
OF ANY GIVEN POINT. THE SYSTEM IS EXTREMELY DYNAMIC WITH THE UPPER TROUGH
BECOMING NEGATIVELY TILTED AS IT SWINGS OUT OF ITS CURRENT POSITION
OVER THE INTERMOUNTAIN WEST AND INTO THE UPPER MIDWEST BY 0Z. DEW
POINTS ACROSS THE AREA ARE ALREADY IN THE UPPER 50S TO AROUND 60 IN
THE SOUTH WITH LOW 60S UPSTREAM. GUIDANCE HIGHS FOR THE DAY HAVE
COME BACK DOWN A BIT GIVEN CLOUD COVER SHOULD BE IN PLACE FOR THE
ENTIRE DAY BUT STILL YIELDS HIGHS ACROSS THE AREA IN THE UPPER 60S
TO LOWER 70S. THUS SURFACE BASED CAPES THE GFS ARE RUNNING IN THE
LOW TO MIDDLE HUNDREDS FOR MIDDAY AND HIGHER IN THE NAM WITH MIXED
LAYER CAPES IN THE LOW HUNDREDS. WHILE THESE INSTABILITY NUMBERS ARE
NOT HIGH...THEY SHOULD BE SUFFICIENT GIVEN SIGNIFICANT SHEAR WITH
LOW LEVEL...MID LEVEL AND UPPER LEVEL JET MAXES GOING THROUGH LATER
TODAY. LONG CURVED HODOGRAPHS AND 0-1 KM HELICITY VALUES OF 300-500
SHOW THE SIGNIFICANT POTENTIAL FOR SUPERCELL AND TORNADO FORMATION.
ONE POSSIBLE WRENCH IN TODAY/S EVENT FOR THIS FORECAST AREA IS THE
OVERNIGHT CONVECTION. A BIT OF CONCERN THAT THIS COULD LEAVE A
STABLE RAIN COOLED AIRMASS OVER THE AREA WITH A BOUNDARY ACROSS THE
SOUTHERN FORECAST AREA OR JUST SOUTH OF THERE THAT COULD IN EFFECT
INHIBIT DEVELOPMENT OVER MUCH OF THE FORECAST AREA DURING THE LATE
MORNING/EARLY AFTERNOON...THUS PREVENTING SUPERCELL DEVELOPMENT.
SHOULD THIS OCCUR...GREAT POTENTIAL WILL STILL BE IN PLACE FOR
SIGNIFICANT DAMAGING WINDS AND SPIN UP TORNADOES WITH THE SQUALL
LINE THAT SHOULD FORM AHEAD OF THE COLD FRONT BY LATE
MORNING/EARLY AFTERNOON ACROSS CENTRAL ILLINOIS.
THE RAPID REFRESH BRINGS THE DEVELOPING SQUALL LINE INTO THE
NORTHWEST COUNTIES AROUND 19Z. THIS AGREES WITH SREF TIMING THAT
BRINGS THE HIGHEST OMEGA THROUGH THE CENTRAL FORECAST AREA AROUND
21Z AND SWINGS THE FRONT AND ASSOCIATED UPWARD MOTION EAST OF THE
AREA BY 0Z AND STUCK WITH THIS TIMING FOR HIGHEST POPS.
ON NON-THUNDERSTORM WIND POTENTIAL...THE LOW PRESSURE SYSTEM WILL
DEEPEN SIGNIFICANTLY AS IT TRAVERSES THE UPPER MIDWEST AND THIS
COULD PRODUCE SOME STRONG WINDS JUST AHEAD OF OR MORE LIKELY JUST
BEHIND THE COLD FRONT. THINK THE STRONGEST OF THESE WINDS WILL STAY
NORTH OF THE FORECAST AREA CLOSER TO THE TRACK OF THE LOW AND THE
GREATEST PRESSURE CHANGES...HOWEVER...WIND ADVISORY STRENGTH GUST OF
50 MPH STILL LOOK LIKE A GOOD POSSIBILITY AND THUS CONTINUED WITH
WIND ADVISORY FOR THE AREA. THINK THE NORTHERN COUNTIES COULD FLIRT
WITH HIGH WIND WARNING CRITERIA...BUT AT THIS POINT THINK THEY WILL
STAY IN HIGH END ADVISORY TERRITORY.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 355 AM EST SUN NOV 17 2013
MODELS SHOW THE COLD FRONT BEING EAST AND SOUTH OF THE FORECAST AREA
BY 0Z TONIGHT...BUT HAVE HELD ONTO POPS IN THE FAR EAST AND SOUTH
FOR THE FIRST FEW HOURS FOR COLLABORATION PURPOSES. BY 3Z HOWEVER
HAVE GONE DRY. AFTER THAT HIGH PRESSURE BUILDS IN FOR THE REMAINDER
OF THE SHORT TERM AND SHOULD SEE MOSTLY CLEAR SKIES AND SLIGHTLY
BELOW NORMAL TEMPERATURES.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 147 AM EST SUN NOV 17 2013
ECMWF AND GFS SHOW DRY WEATHER PERSISTING ACROSS CENTRAL INDIANA
ON WEDNESDAY AS HIGH PRESSURE DEPARTS THE AREA. HOWEVER A WET AND
ACTIVE END TO THE NEXT WORK WEEK LOOKS IN STORE AS SEVERAL WEATHER
SYSTEMS LOOKS TO PUSH ACROSS THE REGION STARTING ON THURSDAY AND
CONTINUING THROUGH SATURDAY. SEVERAL UPPER LEVEL WEATHER SYSTEMS
WITH A MOIST SOUTHWEST FLOW IN PLACE ALOFT WILL PROVIDE SEVERAL
CHANCES AT SHOWERS STARTING ON THURSDAY AND AGAIN ON FRIDAY AS A
WARM FRONTAL BOUNDARY PASSES ACROSS THE OHIO VALLEY.
THE GFS AND ECMWF SHOW A STRONGER COLD FRONT PUSHING ACROSS THE
REGION ON FRIDAY NIGHT...GIVING US ANOTHER SHOT AT PRECIP...ALONG
WITH MUCH COLDER AIR IN THE WAKE OF THE FRONT FOR NEXT WEEKEND.
&&
.AVIATION /DISCUSSION FOR THE 171200Z TAFS/...
ISSUED AT 511 AM EST SUN NOV 17 2013
POOR FLYING CONDITIONS ARE EXPECTED THIS TAF PERIOD AS MVFR TO
IFR CONDITIONS WILL BE EXPECTED FOR THE NEXT 12 HOURS ALONG WITH
GUSTY SOUTH TO SOUTHWEST WINDS.
A STRONG LOW PRESSURE SYSTEM IS EXPECTED TO PUSH ACROSS INDIANA
TODAY. HRRR REFLECTIVITY SHOWS AN EXPECTED BAND OF TSRA TO DEVELOP
AND PUSH ACROSS INDIANA ALONG OR JUST SLIGHTLY AHEAD OF THE COLD
FRONT THIS AFTERNOON. IN THE MEANTIME...RADAR CONTINUES TO SHOW SCT
SHRA ACROSS CENTRAL INDIANA AS WARM AND MOIST AIR ARRIVES IN THE
AREA ON SW WINDS. FORECAST SOUNDINGS SHOW GOOD LOWER LEVEL
MOISTURE THIS MORNING...INDICATING THE MVFR TO IFR CIGS...FOLLOWED
BY STEEP LAPSE RATES ALOFT LATER THIS AFTERNOON AS THE COLD FRONT
APPROACHES AND PASSES. STRONG PRESSURE GRADIENT REMAINS IN PLACE
AS A STRONG LLJ OF 50 KNTS IS EXPECTED TO PASS AHEAD OF THE COLD
FRONT...THUS WILL CONTINUE TO INCLUDE GUSTY WINDS IN THE TAFS.
IN THE WAKE OF THE FRONT...FORECAST SOUNDINGS SHOW STRONG
SUBSIDENCE AND DRYING AND A RETURN TO VFR CONDITIONS BY LATE THIS EVENING.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM NOON TODAY TO 9 PM EST THIS EVENING FOR
INZ021-028>031-035>049-051>057-060>065-067>072.
&&
$$
SYNOPSIS...CP
NEAR TERM...CP
SHORT TERM...CP
LONG TERM....PUMA
AVIATION...JP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS PADUCAH KY
549 AM CST Sun Nov 17 2013
.SHORT TERM...(Today and Tonight)
ISSUED AT 423 AM CST SUN NOV 17 2013
Will have to monitor the embedded linear segment near KPAH at 10Z
closely, but it appears that the severe weather threat for early
this morning may not pan out. We have had some gusts 40 to 50 MPH
generally associated in or close to convective elements, and this
will likely continue through at least daybreak. The current band
of convection should continue to creep eastward and should be
exiting the southeast around 15Z. The latest HRRR was holding onto
it a bit longer til nearly 18Z, so the grids will keep likely pops
through the morning in the far southeast. To the northwest of this
band, little precipitation is expected until early afternoon.
Previous runs of the HRRR and other mesoscale models had been
generating discrete convection over the Evansville Tri State
ahead of the front from midday through mid afternoon. Isolated
supercell storms with the potential for all forms of severe
weather including significant tornadoes would be possible with these
storms if they develop. The latest few HRRR runs have not been
generating the pre-frontal activity, apparently due to some minor
capping developing in the wake of this mornings activity. Will
keep an emphasis in the PoP fields over the Tri State area through
the afternoon, but it will only be good chance to low end likelies
due to the discrete nature of the storms, if they can develop.
The one thing that seems to be a given in all of the models is for
a broken line of most likely discrete supercell thunderstorms to
develop southward along the eastward advancing cold front. This
activity should enter the far northwest portions of southern
Illinois around 19Z, and then continue to develop southward as the
whole line moves east through the afternoon. All of the convection
is expected to be east of the area by 00Z. Southeast Missouri as
well as the Purchase area of west Kentucky may come through this
event unscathed, as the frontal convection moves/develops
southeastward from southern Illinois into the Lakes and Pennyrile
region of west Kentucky late this afternoon. The full gamut of
severe weather will be possible with the frontal convection,
including significant tornadoes. These frontal storms may begin to
coalesce into a line or at least linear segments before exiting
the area. This would result in more of a bowing/damaging wind
threat.
As for the Wind Advisory, only the raw NAM winds are in support,
but given observations this morning the Advisory looks good. Did
modify the winds a bit to emphasize the northern half of the
southern Illinois and the Evansville Tri State for the strongest
winds. However, guidance has trended considerably lower with the
winds behind the cold front, so decided to expire the Advisory at
23Z, instead of the original 02Z.
High pressure will build across the area tonight. Modest west
northwest winds will bring much drier and cooler air to the
region. Did not stray too far from guidance for lows tonight.
Generally favored the warm side of guidance for highs today.
.LONG TERM...(Monday through Saturday)
ISSUED AT 423 AM CST SUN NOV 17 2013
Not much overall change for the extended portion of the forecast.
There is good model agreement with the synoptic features
influencing the area through Thursday, then there is much
divergence. Look for high pressure to finally settle over the
area Monday evening, allowing for good radiational cooling
overnight into Tuesday morning. Definitely undercut guidance for
lows Monday night.
The surface high will shift quickly east Tuesday into Tuesday
night, allowing for weak return southeasterly flow across the
area. As the flow aloft become southwesterly heading into Wednesday,
clouds will begin to increase, and a disturbance will bring a
chance of showers to the area Wednesday night into Thursday.
The ECMWF continues to have a dominant northern stream system and
brings Arctic surface high pressure into the area beginning late
Thursday. The GFS has a stronger southern stream which effectively
holds off the Arctic airmass about 24 hours later. Both models
indicate a decent chance of showers Thursday night into Friday,
but the temperatures would be much warmer if the GFS is right.
Tremendous bust potential here. This forecast still leans a bit
toward the warmer GFS solution. Both models are now clearing the
area out by Saturday morning with somewhat modified Arctic high
pressure building over the region.
&&
.AVIATION...
ISSUED AT 547 AM CST SUN NOV 17 2013
For the 12z Sunday WFO PAH TAF issuance, kept MVFR ceilings in
place through the frontal passage at each location. For
Thunderstorms, the use of vicinity thunder was kept given the
variability and coverage of thunderstorm this after over each of
the sites. Near term changes may be required as the frontal
boundary and associated convection move through later today.
Withing 1 to 3 hours of the cold frontal passage, skies were
cleared out and winds/wind gusts were reduced dramatically.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...WIND ADVISORY until 5 PM CST this afternoon FOR ILZ075>078-
080>094.
MO...WIND ADVISORY until 5 PM CST this afternoon FOR MOZ076-086-087-
100-107>112-114.
IN...WIND ADVISORY until 5 PM CST this afternoon FOR INZ081-082-
085>088.
KY...WIND ADVISORY until 5 PM CST this afternoon FOR KYZ001>022.
&&
$$
SHORT TERM...DRS
LONG TERM...DRS
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS PADUCAH KY
424 AM CST Sun Nov 17 2013
.SHORT TERM...(Today and Tonight)
ISSUED AT 423 AM CST SUN NOV 17 2013
Will have to monitor the embedded linear segment near KPAH at 10Z
closely, but it appears that the severe weather threat for early
this morning may not pan out. We have had some gusts 40 to 50 MPH
generally associated in or close to convective elements, and this
will likely continue through at least daybreak. The current band
of convection should continue to creep eastward and should be
exiting the southeast around 15Z. The latest HRRR was holding onto
it a bit longer til nearly 18Z, so the grids will keep likely pops
through the morning in the far southeast. To the northwest of this
band, little precipitation is expected until early afternoon.
Previous runs of the HRRR and other mesoscale models had been
generating discrete convection over the Evansville Tri State
ahead of the front from midday through mid afternoon. Isolated
supercell storms with the potential for all forms of severe
weather including significant tornadoes would be possible with these
storms if they develop. The latest few HRRR runs have not been
generating the pre-frontal activity, apparently due to some minor
capping developing in the wake of this mornings activity. Will
keep an emphasis in the PoP fields over the Tri State area through
the afternoon, but it will only be good chance to low end likelies
due to the discrete nature of the storms, if they can develop.
The one thing that seems to be a given in all of the models is for
a broken line of most likely discrete supercell thunderstorms to
develop southward along the eastward advancing cold front. This
activity should enter the far northwest portions of southern
Illinois around 19Z, and then continue to develop southward as the
whole line moves east through the afternoon. All of the convection
is expected to be east of the area by 00Z. Southeast Missouri as
well as the Purchase area of west Kentucky may come through this
event unscathed, as the frontal convection moves/develops
southeastward from southern Illinois into the Lakes and Pennyrile
region of west Kentucky late this afternoon. The full gamut of
severe weather will be possible with the frontal convection,
including significant tornadoes. These frontal storms may begin to
coalesce into a line or at least linear segments before exiting
the area. This would result in more of a bowing/damaging wind
threat.
As for the Wind Advisory, only the raw NAM winds are in support,
but given observations this morning the Advisory looks good. Did
modify the winds a bit to emphasize the northern half of the
southern Illinois and the Evansville Tri State for the strongest
winds. However, guidance has trended considerably lower with the
winds behind the cold front, so decided to expire the Advisory at
23Z, instead of the original 02Z.
High pressure will build across the area tonight. Modest west
northwest winds will bring much drier and cooler air to the
region. Did not stray too far from guidance for lows tonight.
Generally favored the warm side of guidance for highs today.
.LONG TERM...(Monday through Saturday)
ISSUED AT 423 AM CST SUN NOV 17 2013
Not much overall change for the extended portion of the forecast.
There is good model agreement with the synoptic features
influencing the area through Thursday, then there is much
divergence. Look for high pressure to finally settle over the
area Monday evening, allowing for good radiational cooling
overnight into Tuesday morning. Definitely undercut guidance for
lows Monday night.
The surface high will shift quickly east Tuesday into Tuesday
night, allowing for weak return southeasterly flow across the
area. As the flow aloft become southwesterly heading into Wednesday,
clouds will begin to increase, and a disturbance will bring a
chance of showers to the area Wednesday night into Thursday.
The ECMWF continues to have a dominant northern stream system and
brings Arctic surface high pressure into the area beginning late
Thursday. The GFS has a stronger southern stream which effectively
holds off the Arctic airmass about 24 hours later. Both models
indicate a decent chance of showers Thursday night into Friday,
but the temperatures would be much warmer if the GFS is right.
Tremendous bust potential here. This forecast still leans a bit
toward the warmer GFS solution. Both models are now clearing the
area out by Saturday morning with somewhat modified Arctic high
pressure building over the region.
&&
.AVIATION...
ISSUED AT 1145 PM CST SAT NOV 16 2013
Strong southerly winds will only further escalate over the next 12
to 18 hours as a vigorous storm system ejects east from the Plains.
By Sunday afternoon, sustained 25 knot winds will frequently gust to
40 to 45 knots even in the absence of thunderstorms. Two time frames
continue to offer the greatest potential for convection. The first
unfolds overnight in response to the passage of an initial wave of
energy. Numerous showers and scattered thunderstorms are expected
with this first round. The second round of potentially severe
thunderstorms will focus during the afternoon hours Sunday as a
strong cold front plows through. MVFR ceilings and VFR visibilities
will prevail through much of the period, though a reduction to MVFR
or IFR conditions may occur beneath showers and thunderstorms. Winds
will shift to the west as skies clear in the wake of the passing
cold front Sunday evening. .. RJP ..
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...WIND ADVISORY from 8 AM this morning to 5 PM CST this afternoon
FOR ILZ075>078-080>094.
MO...WIND ADVISORY from 8 AM this morning to 5 PM CST this afternoon
FOR MOZ076-086-087-100-107>112-114.
IN...WIND ADVISORY from 8 AM this morning to 5 PM CST this afternoon
FOR INZ081-082-085>088.
KY...WIND ADVISORY from 8 AM this morning to 5 PM CST this afternoon
FOR KYZ001>022.
&&
$$
SHORT TERM...DRS
LONG TERM...DRS
AVIATION...RJP
AREA FORECAST DISCUSSION...UPDATED
NWS PITTSBURGH PA
634 AM EST SUN NOV 17 2013
.SYNOPSIS...
A MILD BUT WET DAY IS EXPECTED TODAY. A COLD FRONT WILL CROSS THE
REGION TONIGHT AND WILL PROVIDE WIDESPREAD SHOWERS AND STORMS.
COOLER AIR WILL ARRIVE ON TUESDAY AND WILL LAST THROUGH MUCH OF
THE WEEK. A STRONG COLD FRONT WILL USHER IN MUCH COLDER AIR NEXT
WEEKEND.
&&
.NEAR TERM /THROUGH MONDAY NIGHT/...
UPDATES TO WX AND POP GRIDS TO REFLECT ONGOING AND XPCD EVOLUTION
OF SHWRS. HIGH-RESOLUTION MODELS SHOW THE SHIELD OF SHWRS
PERSISTING FOR MUCH OF THE DAY OVER WRN PA AND NRN WV. CNVCTN WILL
INCR IN CVRG IN FAR WRN ZONES LATE THIS AFTN AS PRIMARY SHRTWV
TROF APRCHS. IF THE HRRR IS TO BE BELIEVED...CELLULAR CNVCTN CAN
BE XPCD AHEAD OF THE PRIMARY CNVCTV LINE. THREATS AS OUTLINED BLW
WOULD APPLY IN SUCH A CASE...SO NO SGFNT CHGS TO LATE AFTN-OVNGT
PDS. PREV DISCUSSION FOLLOWS...
WMFNT OVER NRN KY WILL SHARPEN AND DVLP NWD TDA IN RESPONSE TO
APRCH OF VIGOROUS H5 SHRTWV TROF AND ATTENDANT DPNG SFC CYCLONE.
SFC LOW WILL BE LOCATED IN GRTLKS RGN BY 18/00Z AS NEGATIVELY-
TILTED UPR TROF ACCELERATES THRU THE RGN.
STRONG MSTR ADVCTN IN ASSOCIATION WITH POTENT LOW-LVL JET IS
UNDERWAY. SHWRS HAVE DVLPD AND WILL CONT THE LUGUBRIOUS CONDITIONS
PERIODICALLY THRU THE DAY. IN BETWEEN THESE EPISODES...MODEST
HEATING CAN BE XPCD...ENABLING POCKETS OF MODEST INSTBY TO FORM.
CELLULAR CNVCTN XPCD TO DVLP IN THE WARM SECTOR THIS AFTN IN
IL/IN/MI AS FORCING FOR ASCENT INCRS AND WIND FIELD BCMS INCRGLY
ORGANIZED. BY LATE THIS AFTN...HODOGRAPHS FROM IL TO WRN PA WILL
BE EXTREMELY SUPPORTIVE OF TORNADIC DVLPMT.
PRIMARY LMTG FACTOR FOR SVR WX THIS AFTN IN THE FCST AREA WILL BE
GENL LACK OF DP INSTBY. ANY SVR THREAT THIS AFTN WILL BE CONDITIONAL
ON DVLPMT OF DP MOIST CNVCTN. ATTM...IT APPEARS PRIMARY PCPN WILL
BE WEAKER SHWRS. IF MRNG PCPN CVRG IS LESS THAN ANTICIPATED...
BREAKS IN CLD CVR MAY PROMOTE MORE INSTBY AND POTL FOR EARLIER
ONSET OF SVR WX.
MAIN FOCUS FOR SVR WX WILL BE THIS EVE AS SFC TROF/CDFNT CROSS THE
RGN. VORTICITY-RICH ENVIRONMENT AMID EXTREME KINEMATICS AND INCRG
FORCING FOR ASCENT WILL SUPPORT VIGOROUS LINE OF CNVCTN CAPABLE OF
DMGG WIND GUSTS AND MESOVORTICES/TORNADOES. INDEED...HI-RES MODELS
DEPICT A WELL-ORGANIZED CNVCTV LINE DVLPG ALONG THIS BNDRY AND
IMPACTING ALL OF THE FCST AREA FROM 18/01Z-18/07Z. POCKETS OF SGFNT
WIND DMG ARE ANTICIPATED ALONG THIS BNDRY...PARTICULARLY WHERE
MESOVORTICES DVLP.
WDSPRD HVY RAIN IS NOT ANTICIPATED IN THIS EVENT OWING TO VERY
RAPID STORM MVMT. RAIN TOTALS BY MON MRNG COULD BE AS HIGH AS
RAPID CLRG XPCD IN WAKE OF THE BNDRY PASSAGE. LAPSE RATES IN THE
POST-FRONTAL AMS WILL STEEPEN CONSIDERABLY...PROMOTING DOWNWARD
MIXING OF HIGH-MOMENTUM AIR. WIND IN THIS MIXED LYR WILL EASILY
REACH 40 KT...WITH GUSTS XPCD TO APRCH OR EXCEED THIS MAGNITUDE
FOR A FEW HRS AFTER FROPA. THUS...WIND ADZY WILL BE IN EFFECT
AFTER FROPA THRU 12Z...WHEN GUSTINESS XPCD TO SUBSIDE.
LOW-LVL WINDS WILL VEER TO WNWLY MON EVE...PROMOTING MODEST FETCH
OFF LAKE ERIE COINCIDENT WITH ONSET OF SLGTLY COOLER AIR. ISOLD
LAKE-EFFECT AND LAKE-ENHANCED SHWRS XPCD TO DVLP MON NGT. WITH
TEMPS FALLING BLW FRZG DURG THIS TIME...VERY LGT SNOW ACCUMS WILL
BE PSBL IN NRN ZONES AND ALONG WEST-FACING SLOPES/RDGS. ARRIVAL OF
VERY DRY SFC AMS WILL BRING A RAPID END TO ANY PCPN LATE MON NGT.
MAXIMA TDA WILL BE IN THE LOW-MID 60S...WITH LOW 50S XPCD FOR HIGHS
ON MON. MINIMA WILL BE IN THE LOW-MID 40S TNGT AND UPR 20S-LWR 30S
MON NGT.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
WHILE CYCLONIC NORTHWESTERLY FLOW CONTINUES OVER THE AREA INTO
MONDAY NIGHT AND TUESDAY...A VERY LEAN RH COLUMN LOOKS TO EXIST
AND IN FACT EVEN LOW LEVEL PROFILES BECOME STRONGLY INVERTED. AS A
RESULT...A DEARTH OF CLOUD COVER IS EXPECTED WITH COLD ADVECTION
REALLY ONLY APPARENT AT THE SURFACE...WHILE ALOFT WARM ADVECTION
WILL ALREADY BE KICKING IN. AS A RESULT...VERY STABLE AND DRY
CONDITIONS MEAN CLEAR SKIES...AND WIDE DIURNAL TEMPERATURE SPREADS
SEEM LIKELY TO CONTINUE THROUGH THE SHORT TERM PERIOD. FRIES
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
RUN-TO-RUN MODEL PERFORMANCE HAS BEEN LESS THAN STELLAR IN THE
EXTENDED FORECAST OVER THE PAST FEW CYCLES WITH REGARD TO THE
EVOLUTION FROM WEAK RIDGING MID-WEEK TO RATHER AMPLIFIED TROUGHING
BY NEXT WEEKEND OR SO. IN FACT...WHILE THE 00Z OPERATIONAL ECMWF
AND GFS BOTH SHOW INCREDIBLY LITTLE SPREAD...A DEEPER LOOK AT THE
GEFS MEMBERS AS WELL AS THE CANADIAN AND ITS ENSEMBLES REVEAL SAID
GLOBAL GUIDANCE AGREEMENT MAY BE SERENDIPITOUS MORE THAN IT IS
SKILLFUL. THAT SAID...A STRONG FASTER TREND IS NOTED IN THE
OPERATIONAL GFS/ECMWF LARGELY DUE TO A MORE PRONOUNCED CUTTING OFF
OF A LARGE UPPER CYCLONE OVER THE DESERT SOUTHWEST BY NEXT WEEKEND
UNDER A SPRAWLING UPPER RIDGE THAT ENCOMPASSES THE EASTERN PACIFIC
AND ALL OF THE INTERMOUNTAIN WEST. PREVIOUS MODEL RUNS HAD
ATTEMPTED TO MAINTAIN SOME DEGREE OF UPPER LEVEL CONNECTION
BETWEEN THE UPPER LOW THAT RETROGRADES TOWARD THE SOUTHWEST AND
THE DEEPENING NORTHERN STREAM UPPER TROUGH AS IT DIGS INTO THE
NORTHERN PLAINS. THE SOLUTIONS THAT MAINTAIN SOME UPPER LEVEL
CONNECTION OR ARE SLOWER TO SEVER SAID CONNECTION RETARD THE
PROGRESS OF THE UPPER TROUGH AND ASSOCIATED MUCH COLDER AIR TOWARD
OUR REGION.
WHILE THE SPEED AT WHICH COLD AIR ARRIVES IN THE AREA IS STILL TO
BE DETERMINED...THERE IS SEEMINGLY STRONG AGREEMENT THAT A DEEP
UPPER THROUGH WILL EVENTUALLY MAKES ITS WAY HERE SOMETIME BETWEEN
THE WEEKEND AND START OF NEXT WEEK. AS SUCH...DRY CONDITIONS ARE
LIKELY TO CONTINUE UNTIL SOUTHWESTERLY MOISTURE AND WARM ADVECTION
AHEAD OF THE ATTENDANT COLD FRONT ARRIVE IN THE AREA VERY LATE
THIS UPCOMING WEEKEND. POPS WERE INCREASED FRIDAY NIGHT AND
SATURDAY WITH THE MOST LIKELY TIME OF THE COLD FRONTAL PASSAGE
LIKELY TO BE ON SATURDAY AT THIS JUNCTURE. THAT
SAID...TEMPERATURES WERE ALLOWED TO STAY ELEVATED BEFORE SATURDAY
BEFORE TRANSITIONING MUCH COLDER BY SUNDAY. AN EARLY LOOK AT THE
DAY 8 GUIDANCE WOULD SUGGEST HIGHS BY SUNDAY UNDER 850 MB
TEMPERATURES OF -16 TO -20C OVER THE AREA WILL BE LIKELY TO REMAIN
LARGELY IN THE 20S. THIS WOULD BE ROUGHLY 20 DEGREES BELOW NORMAL
BY THAT TIME. AS SUCH...LAKE EFFECT SNOW SEEMS LIKELY TO RETURN TO
THE FORECAST BY THAT TIME AS WELL. FRIES
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
PERIODIC SHWRS XPCD TO IMPACT ALL TERMINALS THRU THE DAY. GENL
VFR/MVFR CONDS SHOULD PREDOMINATE OUTSIDE OF ANY SHWRS. WIND SHEAR
REMARKS WERE INCLD IN ALL TAFS THRU MID-MRNG OWING TO PRESENCE OF
STEEP INVERSION. THIS INVERSION WILL MIX OUT BY MID-MRNG...WITH
GUSTY SLY WINDS XPCD ALL TERMINALS.
ORGANIZED LINE OF SHWRS/TSTMS WILL MOVE THRU THE RGN TNGT IN
ASSOCIATION WITH SFC TROF/CDFNT. THE LINE SHOULD ENTER PA AROUND
18/03Z AND WILL CROSS THE APLCNS BY 18/06Z. THIS LINE LKLY WILL BE
ACCOMPANIED BY MDT RAIN AND BRIEF WIND GUSTS IN EXCESS OF 50-60
KT. CIGS AND VSBYS COULD BE REDUCED TO IFR OR LWR WHEN THE LINE
PASSES.
RAPID CLRG XPCD IN THE WAKE OF THE LINE. GUSTY WLY WINDS WILL
ENSUE FOR SVRL HRS OWING TO STEEP LOW-LVL LAPSE RATES IN THE POST-
FRONTAL AMS. VFR CONDS XPCD THRU MON.
.OUTLOOK.../MONDAY NIGHT THROUGH THURSDAY/...
VFR CONDITIONS WILL RETURN LATER TUESDAY AND CONTINUE INTO
THURSDAY AS HIGH PRESSURE BUILDS OVERHEAD.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WIND ADVISORY FROM 1 AM TO 7 AM EST MONDAY FOR MDZ001.
OH...WIND ADVISORY FROM 10 PM THIS EVENING TO 7 AM EST MONDAY FOR
OHZ039>041-048>050-057>059-068-069.
PA...WIND ADVISORY FROM MIDNIGHT TONIGHT TO 7 AM EST MONDAY FOR
PAZ007>009-013>016-020>023-029-031-073-075.
WIND ADVISORY FROM 1 AM TO 7 AM EST MONDAY FOR PAZ074-076.
WV...WIND ADVISORY FROM 10 PM THIS EVENING TO 7 AM EST MONDAY FOR
WVZ001>004-012.
WIND ADVISORY FROM MIDNIGHT TONIGHT TO 7 AM EST MONDAY FOR
WVZ021-022.
WIND ADVISORY FROM 1 AM TO 7 AM EST MONDAY FOR WVZ023-041.
&&
$$
KRAMAR/FRIES
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
655 AM EST SUN NOV 17 2013
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 326 AM EST SUN NOV 17 2013
PEOPLE IN SOUTHWEST LOWER MICHIGAN SHOULD PAY ATTENTION TO THE
WEATHER TODAY BECAUSE IT LOOKS LIKE WE/RE GOING TO SEE A SIGNIFICANT
WIND EVENT. A HIGH WIND WARNING IS IN EFFECT FOR ALL OF SOUTHWEST
LOWER MICHIGAN FROM 4 PM THIS AFTERNOON THROUGH 4 AM MONDAY.
A STRONG AUTUMN STORM WILL STRENGTHEN AS IT MOVES FROM IOWA
TOWARD THE LEELANAU PENINSULA. SHOWERS AND THUNDERSTORMS WILL
CONTINUE TO DEVELOP TODAY AS A WARM FRONT MOVES NORTH. HOWEVER
THIS AFTERNOON...STORMS WILL LIKELY BECOME STRONG TO SEVERE AS
VERY STRONG DYNAMICS TAP INTO A MOISTURE RICH AIRMASS AHEAD OF THE
APPROACHING COLD FRONT. WIND GUSTS IN EXCESS OF 60 MPH ARE
POSSIBLE THIS AFTERNOON ALONG WITH ISOLATED TORNADOES. THE STORM
PREDICTION CENTER MAINTAINS A MODERATE RISK OF SEVERE STORMS
ACROSS CENTRAL LOWER MICHIGAN TODAY WITH A HIGH RISK REACHING INTO
SOUTHERN LOWER MICHIGAN.
MIXED RAIN/SNOW SHOWERS ARE EXPECTED MONDAY AS HIGHS FALL BACK TO
THE LOWER 40S.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 326 AM EST SUN NOV 17 2013
LATEST MODEL RUNS DIDN/T CHANGE THE THINKING THAT WE/RE STARING AT A
SIGNIFICANT WIND THREAT TODAY. STRONG TO SEVERE STORMS ARE POSSIBLE
ESPECIALLY THIS AFTERNOON FOLLOWED BY STRONG GRADIENT WINDS BEHIND
THE COLD FRONT LATE AFTERNOON AND EVENING. AS A RESULT WE ISSUED A
HIGH WIND WARNING THAT/S IN EFFECT FROM 4 PM TODAY THROUGH 4 AM
MONDAY.
A NEGATIVELY TILTED TROUGH WILL APPROACH THE GREAT LAKES. SFC LOW
PRESSURE IN THE MISSOURI VALLEY WILL MOVE TOWARD THE LEELANAU
PENINSULA LATE TODAY. A WARM FRONT LIFTING NORTH WILL BE AN INITIAL
FOCUS FOR CONVECTION. HOWEVER THE MAIN SHOW WILL BE THIS AFTERNOON
AHEAD OF THE COLD FRONT. A LOW LEVEL JET NEAR 65 KNOTS COUPLED WITH
A MID LEVEL JET NEAR 95 KNOTS WILL GENERATE SIGNIFICANT SHEAR THIS
AFTERNOON. IN ADDITION THE LEFT EXIT REGION OF THE UPPER JET WILL
MOVE OVER THE CWA LATE THIS AFTERNOON. IF WE CAN REALIZE CLOSE TO
THE 800 J/KG MLCAPE THE MODELS INDICATE WE SHOULD HAVE MORE THAN
ENOUGH FORCING AND ORGANIZATION FOR SUPERCELLS TO DEVELOP AHEAD OF
THE COLD FRONT. THE STRONG SHORT WAVE MOVING IN AT THE SAME TIME
WILL ONLY AID IN THE LIFT.
SPC MAINTAINS A MODERATE RISK FOR SEVERE STORMS WITH A HIGH RISK
JUST SOUTH OF THE CWA. CAN/T ARGUE WITH THAT. THE HRRR SHOWS A
BROKEN LINE OF STORMS ARRIVING AT THE SHORE AROUND 20Z. THIS
TIMING IS CONSISTENT WITH OTHER MODELS. THE MAIN SEVERE THREAT
LOOKS TO BE FROM 20Z THROUGH 01Z. AFTER THE COLD FRONT SWEEPS
THROUGH THE ATTENTION WILL TURN TO SYNOPTIC WINDS.
THE WIND THREAT WILL CONTINUE THIS EVENING. NAM SHOWS 3 HRLY
PRESSURE RISES IN THE 9-10 MB RANGE WHICH IS PRETTY HIGH AND SHOULD
RESULT IN HIGH WIND WARNING TYPE WINDS...ESPECIALLY ALONG THE COAST
WHERE GUSTS TO 55-65 MPH ARE POSSIBLE. STRONG COLD ADVECTION WILL
HELP TO PULL DOWN THE 55 KNOTS SEEN AT 900 FEET ON BUFKIT WIND
PROFILES. SURE SEEMS LIKE SCATTERED POWER OUTAGES WILL BE POSSIBLE
FROM THIS AFTERNOON THROUGH TONIGHT. WINDS WILL DIMINISH LATE
TONIGHT.
MIXED RAIN/SNOW SHOWERS POSSIBLE MONDAY/TUESDAY AS HIGHS ONLY CLIMB
INTO THE LOWER 40S.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 326 AM EST SUN NOV 17 2013
NO BIG STORMS IN THE EXTENDED. BUMPED UP MAXES A BIT ON WEDNESDAY AS
EURO HAS 850 MB TEMPS AROUND 5C WHICH LOOKS REASONABLE GIVEN DEEP
SOUTHERLY FLOW. ENOUGH MOISTURE MAY BE DRAWN NORTHWARD TO BRING SOME
SHOWERS BY WEDNESDAY NIGHT INTO THURSDAY AS IT POOLS IN FRONT OF
ADVANCING COLD FRONT.
COLDER AIR FILTERS IN FOR THURSDAY NIGHT AND FRIDAY WITH PRECIP
TRANSITIONING TO SNOW BY FRIDAY NIGHT. FORECAST CONFIDENCE IN THE
DETAILS IS LOW WITH POOR RUN TO RUN CONSISTENCY FOR FRIDAY AND
SATURDAY. THE GFS HAS A SFC LOW AND SECONDARY COLD FRONT COMING
THROUGH FRIDAY WHILE THE EURO IS FURTHER NORTH AND SLOWER WITH THE
LOW. SHOULD BE COLD ENOUGH FOR ALL SNOW BY FRIDAY NIGHT AND SATURDAY
IN EITHER SCENARIO.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 655 AM EST SUN NOV 17 2013
WIDESPREAD MVFR AND PATCHY IFR CONDITIONS THIS MORNING IN ADVANCE
OF A SQUALL LINE EXPECTED TO MOVE THROUGH FROM WEST TO EAST
BETWEEN 19Z TO 22Z. WIND GUSTS WITH THE SQUALL LINE COULD BE IN
EXCESS OF 50 KNOTS ALONG WITH THE POTENTIAL FOR LARGE HAIL AND
TORNADOES. ONCE THIS MOVES THROUGH...HIGH WIND THREAT CONTINUES
WITH WIDESPREAD GUSTS OVER 40 MPH AND AS HIGH AS 60 MPH DURING THE
EVENING. WINDS WILL START OUT SOUTH THIS MORNING...GO SOUTHWEST
THIS AFTERNOON AND THEN WEST LATER TONIGHT.
&&
.MARINE...
ISSUED AT 326 AM EST SUN NOV 17 2013
UPGRADED THE GALE WARNING TO A STORM WARNING. IN ADDITION TO STRONG
TO SEVERE THUNDERSTORMS TODAY STRONG GRADIENT WINDS WILL DEVELOP
BEHIND A COLD FRONT LATE THIS AFTERNOON. WEST STORM FORCE WINDS TO
55 KNOTS ARE EXPECTED THROUGH THE EARLY OVERNIGHT HOURS BEFORE
DECREASING TO 40 KNOT GALES. WAVES WILL BUILD TO 10 TO 15 FEET
TONIGHT.
&&
.HYDROLOGY...
ISSUED AT 326 AM EST SUN NOV 17 2013
HEAVY RAINFALL POSSIBLE IN STORMS TODAY...ESPECIALLY THIS AFTERNOON.
LOOK FOR ADDITIONAL RAINFALL ACCUMULATIONS AROUND AN INCH THROUGH
EARLY EVENING. THIS LIKELY WON`T CAUSE RIVER FLOODING. HOWEVER
LOCALIZED FLOODING MAY DEVELOP IN POOR DRAINAGE AREAS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...HIGH WIND WARNING FROM 4 PM THIS AFTERNOON TO 4 AM EST MONDAY
FOR MIZ037>040-043>046-050>052-056>059-064>067-071>074.
LM...STORM WARNING FROM 4 PM THIS AFTERNOON TO 4 AM EST MONDAY FOR
LMZ844>849.
GALE WARNING UNTIL 4 PM EST THIS AFTERNOON FOR LMZ844>849.
&&
$$
SYNOPSIS...93
SHORT TERM...93
LONG TERM...OSTUNO
AVIATION...OSTUNO
HYDROLOGY...93
MARINE...93
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
624 AM CST SUN NOV 17 2013
.UPDATE...FOR 12Z AVIATION DISCUSSION BELOW
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 410 AM CST SUN NOV 17 2013
THE SURFACE LOW HAD ENTERED NORTHEASTERN MN BY 09Z THIS MORNING. FOG
AND STRATUS CLOUDS ON THE WEST/SOUTHWEST PERIPHERY OF THE LOW
PLAGUED NORTH CENTRAL INTO WEST CENTRAL MN OVERNIGHT. AS THE LOW
MEANDERS NORTH AND EAST THIS MORNING...NORTHWEST WINDS WILL
STRENGTHEN. SHOULD SEE FOG IMPROVE DURING THE MID TO LATE
MORNING...BUT CYCLONIC FLOW WILL LIKELY BE CONDUCIVE TO PROLONGED
LOW CLOUD COVER...WITH THE EXCEPTION OF WEST AND SOUTH CENTRAL MN
WHERE SOME AFTERNOON BREAKS ARE POSSIBLE. THE EXTENSIVE CLOUD COVER
AND COLD AIR ADVECTION TODAY WILL RESULT IN LIMITED DIURNAL
WARMING...WITH HIGH TEMPERATURES IN THE 40S. PRECIPITATION IS
EXPECTED TO STAY CONFINED TO THE FAR SOUTHERN/SOUTHEASTERN PORTION
OF THE FORECAST AREA /SOUTH CENTRAL MN NORTHEAST TO NEAR EAU CLAIRE
WI/ DURING THE DAYTIME HOURS. ADDITIONAL RAINFALL AMOUNTS SHOULD MAX OUT
AROUND ONE TENTH OF AN INCH OR LESS. A VERY BRIEF PERIOD OF SNOW
WILL BE POSSIBLE IN THE NORTHEAST NEAR LADYSMITH TONIGHT...BUT THE
PRECIP IS EXPECTED TO PRETTY MUCH BE FINISHED BY THE TIME IT
TRANSITIONS TO SNOW.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 410 AM CST SUN NOV 17 2013
RELATIVELY QUIET WEATHER IS EXPECTED FOR THE UPCOMING WEEK ONCE
THIS POWERFUL CYCLONE EXITS THE REGION. THE MAIN CONCERN IS TRYING
TO TIME THE COLD FRONT THAT WILL MOVE THROUGH AND WEDNESDAY...AND
ANY ASSOCIATED PRECIP THAT MAY ACCOMPANY IT.
AT THE START OF THE PERIOD HIGH PRESSURE WILL BE BUILDING ACROSS THE
UPPER MIDWEST...AND THE LARGE SCALE SUBSIDENCE RESPONSIBLE FOR THIS
SURFACE HIGH WILL KEEP THE REGION DRY. AS THIS HIGH SLIDES EASTWARD
WARM AIR ADVECTION WILL OVERSPREAD THE WEST LATE MONDAY INTO TUESDAY
NIGHT. FORECAST SOUNDINGS FOR TUESDAY OFF THE GFS SHOW SOUTHERLY
WINDS OF 20KTS THROUGHOUT THE MIXED LAYER WITH ONLY A FEW HIGH
CLOUDS POSSIBLE. THIS SHOULD RESULT IN AFTERNOON TEMPERATURES
SIMILAR TO THE PAST COUPLE OF DAYS...SO RAISED TEMPERATURES ABOVE
GUIDANCE WITH MID 50S ON THE LEE SIDE OF THE BUFFALO
RIDGE...TAPERING TO UPPER 40S ACROSS THE NORTHERN PORTION OF THE
CWA. CONFIDENCE BEYOND THIS PERIOD IS LOW.
ON TUESDAY NIGHT AN UPPER LEVEL TROUGH WILL MOVE ACROSS SOUTHERN
CANADA AND CAUSE A SURFACE LOW TO DEVELOP...WITH A TRAILING COLD
FRONT FORECAST TO MOVE THROUGH THE REGION ON WEDNESDAY. THE GEM AND
ECMWF ARE FASTER WITH THIS FRONT THAN THE GFS. ALSO THE ECMWF HAS
POST FRONTAL PRECIP DRIVEN BY THE MID LEVEL FGEN...WHEREAS THE GFS
KEEPS THE PRECIP CONFINED TO THE DAKOTAS. HAVE DECIDED TO KEEP POPS
FOR WEDNESDAY NIGHT THROUGH FRIDAY DUE TO THE HIGH UNCERTAINTY IN
THE FORECAST. AS MENTIONED EARLIER...THE POLAR JET WILL BE OVER
SOUTHERN CANADA...WHILE THE SOUTHERN STREAM DIGS A TROUGH OVER THE
DESERT SOUTHWEST. HOW THESE TWO FEATURES PHASE ACROSS THE MIDWEST
WILL DETERMINE IF SIGNIFICANT SNOW DEVELOPS TOWARD THE END OF THE
WEEK...AS INDICATED BY THE GFS AND GEM...OR IF THE COLD ARCTIC
HIGH PRESSURE KEEPS THE REGION DRY AND COOL. FOR NOW DID NOT
HAVE THE CONFIDENCE TO LEAN TOWARDS ANY PARTICULAR SOLUTION...SO
STUCK WITH THE 20POPS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 623 AM CST SUN NOV 17 2013
STRATUS CLOUDS ASSOCIATED WITH THE AREA OF LOW PRESSURE MOVING
FROM NORTHEASTERN MN TOWARD THE GREAT LAKES WILL PLAGUE THE TAF
SITES THIS MORNING...WITH SUB-1000FT CIGS AND AREAS OF BR WITH
MVFR VSBYS. THE RAP 0.5KM AGL CONDENSATIONAL PRESSURE DEFICIT PROG
HAS BEEN REFLECTING THE ACTUAL TRENDS FAIRLY WELL...AND INDICATES
A FEW BREAKS IN THE LOW CLOUDS DEVELOPING EVENTUALLY TODAY
/ESPECIALLY FROM NEAR KRWF TO NEAR OR JUST SOUTH OF KMSP/...AROUND
21Z. HAVE THEREFORE INCLUDED SLIGHT IMPROVEMENTS IN CIGS FOR THIS
AFTERNOON. PRECIPITATION IS EXPECTED TO FALL MOSTLY SOUTHEAST OF THE
TAF SITES...ALTHOUGH LIGHT RAIN MAY SCRAPE KEAU DURING THE LATE
MORNING AND EARLY AFTERNOON HOURS. WINDS WILL BECOME GUSTY FROM
THE NORTHWEST...NEARING SUSTAINED SPEEDS OF 20 KTS WITH GUSTS TO
30 KTS. SUBSTANTIAL SCOURING OUT OF THE LOW CLOUDS DOES NOT APPEAR
AS IF ITS GOING TO HAPPEN UNTIL LATE TONIGHT AND MONDAY MORNING.
KMSP...
EXPECT CIGS TO PERSIST THROUGH THE MORNING...WITH MVFR VSBYS
LIKELY AS WELL. VSBYS SHOULD IMPROVE TO VFR BY 18Z...WITH SOME
IMPROVEMENT IN CIGS TO MVFR EXPECTED AROUND/AFTER 18Z. VFR
CONDITIONS ARE EXPECTED TO DEVELOP OVERNIGHT...WITH MOSTLY CLEAR
SKIES BY DAYBREAK MONDAY. SOUTHWEST WINDS SHIFT TO 290-300 DEGREES
BY 18Z AND INCREASE TO SUSTAINED 15-18KT SPEEDS WITH GUSTS TO AROUND 25
KTS. WINDS DECREASE A TAD THIS EVE...BUT ARE EXPECTED TO CONTINUE
GUSTING TO NEARLY 25 KTS THROUGH MUCH OF TONIGHT.
/OUTLOOK FOR KMSP/
MON...MVFR CIGS EARLY...THEN VFR. WINDS WNW AT 10G15KTS.
TUE...VFR. WINDS SE AT 10-15KTS.
WED...VFR WITH MVFR AND -RA LATE. WINDS SSW AT 10G15KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...LS
LONG TERM...JRB
AVIATION...LS
AREA FORECAST DISCUSSION
NWS BUFFALO NY
729 AM EST SUN NOV 17 2013
.SYNOPSIS...
LOW PRESSURE WILL RAPIDLY STRENGTHEN ACROSS THE UPPER LAKES
TODAY...WHICH WILL SWEEP A POWERFUL COLD FRONT ACROSS OUR REGION
TONIGHT. AHEAD OF THE FRONT WILL BE WARM TEMPERATURES AND SOME
SHOWERS...WITH A LINE OF SEVERE THUNDERSTORMS POSSIBLE ALONG THE
FRONT TONIGHT. THERE WILL ALSO BE GUSTY WINDS AHEAD OF THE FRONT AND
MORE WIDESPREAD STRONG WINDS BEHIND THE FRONT. THE FRONT WILL
EVENTUALLY USHER IN COOLER TEMPERATURES MONDAY NIGHT THROUGH
TUESDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
LOW PRESSURE DEVELOPING ACROSS MINNESOTA THIS MORNING WILL
RAPIDLY INTENSIFY AS IT LIFTS ACROSS THE UPPER LAKES TODAY. THE
INTENSE LOW WILL CLOSE OFF ALOFT SOUTH OF HUDSON BAY AS IT SWEEPS
A STRONG COLD FRONT ACROSS WESTERN NEW YORK TONIGHT. THIS WILL
BRING STRONG SYNOPTIC WINDS TO SOME LOCATIONS...AND POSSIBLY SOME
SEVERE WEATHER WITH THE FRONTAL PASSAGE. NOW FOR THE DETAILS...
TODAY WILL GET OFF TO A WARM START...WITH MORNING TEMPERATURES
ALREADY IN THE 50S IN MANY LOCATIONS. TEMPERATURES RISE INTO THE
UPPER 50S ACROSS HIGHER TERRAIN AND INTO THE MID 60S IN DOWNSLOPE
REGIONS NORTH OF I-90. AN AREA OF SHOWERS HAS DEVELOPED WELL
AHEAD OF THE COLD FRONT IN THE OHIO VALLEY. MUCH OF THE SUPPORT
FOR THESE SHOWERS IS FROM THE COMBINATION OF UPPER LEVEL LIFT AND
MOISTURE ADVECTION WITH THE DEVELOPING LLJ. SHOWERS WILL
GRADUALLY WEAKEN AS THE SSW FLOW LIFTS THEM AHEAD OF SYNOPTIC
SUPPORT AND INTO OUR REGION THIS MORNING. THIS WILL BRING A PERIOD OF
SHOWERS TO MOST THIS MORNING...BUT HIGH RESOLUTION MODEL GUIDANCE (00/06Z
NAM/RGEM/HRRR) HAS BEEN FAIRLY CONSISTENT IN FORECASTING A BREAK
BETWEEN THIS INITIAL ROUND AND COLD FRONT. WITH SUPPORT FROM IR
SATELLITE TRENDS..EXPECT MOST AREAS WILL GET A BREAK FROM THE
SHOWERS THIS AFTERNOON...WITH JUST WARM AND BREEZY CONDITIONS UNTIL
THE NEXT ROUND OF SHOWERS MOVES IN FROM THE SOUTHWEST LATE
AFTERNOON. WINDS WILL BE GUSTY TODAY DUE TO A 45 KNOT FLOW ALOFT.
FOR THE MOST PART...THIS WILL NOT MIX DOWN TO THE SURFACE...EXCEPT
ALONG THE CHAUTAUQUA RIDGE AND BLACK RIVER VALLEY WHERE GUSTS TO
40 MPH ARE LIKELY. THIS SAID...EXPECT DAMAGING WINDS TO HOLD OFF
UNTIL THIS EVENING WHEN WINDS ALOFT INCREASE.
NEARLY ALL LOCATIONS WILL EXPERIENCE STRONG WINDS AT SOME POINT
TONIGHT. ALTHOUGH THE TRACK OF THE LOW IS A BIT NW OF THE
TYPICALLY FAVORED TRACK FOR HIGH WINDS IN OUR REGION...THE SHEAR
INTENSITY OF THE 970MB LOW AS IT CLOSES OFF ALOFT SUPPORTS A
SIGNIFICANT WIND DAMAGE THREAT FOR OUR REGION. THE FIRST ISSUE
WILL BE THE INCREASING LOW LEVEL JET OUT AHEAD OF THE FRONT...WITH
BUFKIT FOR THE GFS/NAM/SREF ENSEMBLE SUPPORTING A PREFRONTAL LLJ
OF 65 KTS AT 925MB. WHILE THIS IS NOT EXPECTED TO MIX TO THE
SURFACE IN MOST LOCATIONS...EXPECT DAMAGING GUSTS WILL MIX OFF THE
CHAUTAUQUA RIDGE AND BLACK RIVER VALLEY. BECAUSE OF
THIS...THE HIGH WIND WARNING NOW ALSO INCLUDES LEWIS AND JEFFERSON
COUNTIES. ELSEWHERE THE CONFIDENCE IN SYNOPTIC DAMAGING WINDS IS
LOWER. THE BIG QUESTION WILL BE TO WHAT EXTENT WINDS MIX ACROSS
HIGHER TERRAIN. GIVEN THE POTENTIAL FOR 60 MPH WINDS STILL
EXISTS...HAVE KEPT THE HIGH WIND WATCH IN PLACE. HOWEVER...00Z/06Z
GUIDANCE SEEMS TO SUGGEST MORE OF AN ADVISORY TYPE EVENT ACROSS
INTERIOR SECTIONS. THIS WILL CONTINUE TO BE MONITORED...WITH
FUTURE TRENDS IN THE STRENGTH OF THE LLJ KEY TO THIS HEADLINE
DECISION.
IN ADDITION TO SYNOPTIC WINDS...PRECIPITATION ALONG THE FRONT ITSELF
MAY MIX STRONG WINDS ALOFT AND RESULT IN CONVECTIVELY DRIVEN
DAMAGING WINDS. THERE ALSO MAY BE A TEMPORARY BURST IN WINDS
IMMEDIATELY BEHIND THE FRONT AS A STRONG SHORTWAVE PIVOTS AROUND THE
RAPIDLY DEEPENING LOW. BECAUSE OF THIS...SPC HAS WESTERN NEW YORK IN
A SLIGHT RISK FOR SEVERE WEATHER...WITH DAMAGING WINDS THE MAIN
THREAT. THE FRONT WILL ENTER WESTERN NEW YORK THIS EVENING...AND
QUICKLY SWEEP ACROSS THE REGION DURING THE EARLY MORNING HOURS.
FORECAST HEDGES ON THE FASTER SIDE OF MOST GUIDANCE...WITH THE
FRONT LIKELY TO ACCELERATE SIMILAR TO THE HRRR FORECAST.
SHOWERS SHOULD END QUICKLY FROM WEST TO EAST...WITH THE ATMOSPHERE
BRIEFLY DRYING OUT IMMEDIATELY BEHIND THE FRONT. TEMPERATURES WILL
QUICKLY COOL INTO THE 40S BEHIND THE FRONT. WINDY CONDITIONS WILL
CONTINUE...WITH WEAKER WINDS ALOFT BEING OFFSET BY BETTER MIXING
IN THE COLD AIR ADVECTION.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
THIS TIME PERIOD WILL TRANSITION FROM THE MILD AND POTENTIAL
SEVERE/WINDY WEATHER TO MORE WINTRY.
BY 12Z MONDAY THE COLD FRONT AND ITS ASSOCIATED PRECIPITATION WILL
BE EAST OF THE REGION. THE SURFACE LOW...THAT NOW WILL BE ENTERING
INTO AND CROSSING QUEBEC WILL CONTINUE TO DEEPEN MONDAY MORNING
BENEATH A NEGATIVELY TILTED UPPER LEVEL TROUGH. WINDS AROUND THIS
AREA OF LOW PRESSURE WILL BRING MUCH COLDER AIR ALOFT ACROSS OUR
REGION WHICH WILL AID IN MIXING STRONGER WIND GUSTS DOWN TO THE
SURFACE. ALSO A STRONG PRESSURE GRADIENT ORIGINATING FROM THIS DEEP
AREA OF LOW PRESSURE IN ADDITION TO GOOD PRESSURE RISES BEHIND THE
FRONT WILL CONTINUE TO BRING GUSTY TO STRONG WINDS ACROSS THE
REGION. STRONGEST WINDS...ONES THAT WILL NEAR 60 MPH WILL BE FOUND
DOWNWIND OF LAKE ERIE AND INLAND TOWARDS MONROE COUNTY...AND ALSO
ACROSS THE NORTH COUNTRY AND THE SAINT LAWRENCE VALLEY. FARTHER
INLAND ACROSS THE SOUTHERN TIER AND UPPER GENESEE VALLEY AND FINGER
LAKES REGION WILL LEAVE THE HIGH WIND WATCH IN EFFECT...AS WIND
GUSTS MAY REMAIN WITHIN ADVISORY LEVEL CRITERIA.
BEHIND THE COLD FRONT 850 HPA TEMPERATURES WILL DROP TO AROUND -6C
OVER THE LAKES MONDAY...WHICH WITH THE +8C OR SO LAKES WILL LIKELY
BRING LAKE EFFECT RAIN SHOWERS THROUGH THE DAY MONDAY. WITH A STILL
WSW WIND LIGHT BANDS OF RAIN WILL LIKELY BE JUST TO THE SOUTH OF
BUFFALO...AND ACROSS WATERTOWN AND TOWARDS THE SAINT LAWRENCE RIVER
MONDAY MORNING. AS THE COLD AIR DEEPENS AND WINDS VEER AROUND TO
WEST...AND THEN NORTHWEST THESE BANDS OF LAKE EFFECT SHOWERS WILL
DROP SOUTHWARD. MODEL SOUNDINGS SUGGEST THAT PRECIPITATION WILL STAY
MAINLY RAIN THROUGH THE DAY...AND THEN AS THE COLDER AIR DEEPENS TO
AROUND -8 TO -10C MONDAY NIGHT PRECIPITATION WILL CHANGE OVER TO
LAKE EFFECT SNOW SHOWERS.
ONE CONCERN FOR LATER MONDAY NIGHT IS DEPTH OF THE MOISTURE WILL BE
BELOW THE GOOD SNOW CRYSTAL GROWTH ZONE. THIS MAY ALLOW FOR SOME
FREEZING DRIZZLE TO DEVELOP LATER IN THE NIGHT. THIS MINIMAL
MOISTURE IN THE SNOW GROWTH ZONES WILL ALSO HOLD ACCUMULATION TO THE
LIGHTER SIDE MONDAY NIGHT.
TUESDAY LAKE EFFECT PRECIPITATION WILL END THROUGH THE MORNING
HOURS AS TEMPERATURES BEGIN TO WARM ALOFT AND HIGH PRESSURE FUNNELS
SOME DRIER AIR ACROSS THE LAKES. THIS DRIER AIR WILL ALSO HELP TO
ERODE THE LOW CLOUDS AND ALLOW FOR SOME SUNSHINE THROUGH THE DAY.
THOUGH SOME SUNSHINE WILL DEVELOP...OUR HIGHS TUESDAY WILL ONLY
REACH INTO THE MID AND UPPER 30S...WHICH WILL BE A RETURN BACK TO
BELOW NORMAL TEMPERATURES. CLEARING SKIES TUESDAY NIGHT AND LIGHT
WINDS SHOULD BRING WIDESPREAD 20S AT NIGHT WITH A FEW OF THE COLDER
VALLEYS OF THE INLAND SOUTHERN TIER AND NORTH COUNTRY POSSIBLY
DROPPING INTO THE UPPER TEENS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
TRANQUIL WEATHER WILL CHARACTERIZE THE FIRST HALF OF THIS PERIOD AS
A BROAD SURFACE RIDGE BUILDS ACROSS THE GREAT LAKES AND NORTHEAST
PART OF THE COUNTRY.
THE SURFACE HIGH SHOULD BRING MOSTLY SUNNY SKIES WEDNESDAY AS IT
CRESTS OVER NEW YORK STATE NEW ENGLAND. AS THE HIGH SETTLES OFF THE
NEW ENGLAND COAST THURSDAY...THERE WILL BE SOME INCREASE IN CLOUDS
AS A COLD FRONT SHIFTS EAST TOWARD THE LOWER LAKES. THE FRONT WILL
BRING A CHANCE FOR RAIN AND SNOW SHOWERS...ACROSS THE LAKE ONTARIO
REGION THURSDAY AND THURSDAY NIGHT. A BETTER CHANCE WILL BE LATER
FRIDAY AND SATURDAY WHEN A STRONG COLD FRONT CROSSES THE REGION WITH
CHANCES FOR RAIN AND SNOW. WINDS WILL ALSO BECOME STRONGER BEHIND
THIS COLD FRONT TO START THE WEEKEND...THOUGH MODEL SOUNDINGS
SUGGEST THE LOW LEVEL JET WILL NOT BE AS STRONG AS THIS SUNDAY`S
EVENT.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AN AREA OF SHOWERS WILL MOVE FROM NORTHEASTER OHIO TO NORTHWESTERN
NEW YORK THROUGH THE MORNING HOURS. EXPECT THIS AREA TO EXIT EAST
OF LAKE ONTARIO EARLY AFTERNOON WHICH WILL PROBABLY PROVIDE A
BRIEF BREAK FOR MOST SITES DURING THE AFTERNOON HOURS. FOR THE
MOST PART...TAF LOCATIONS SHOULD STAY VFR TODAY...WITH THE
EXCEPTION OF THE SOUTHERN TIER (JHW) WHERE IFR/MVFR CIGS WILL
LIKELY PERSIST FOR MUCH OF THE DAY.
SOUTHERLY WINDS OF 40 TO 50 KTS WILL PERSIST THROUGH MOST OF THE
DAY. INITIALLY THIS WILL RESULT IN LLWS AT MOST TAF LOCATIONS SINCE
IT WILL NOT MIX DOWN...BUT SUSPECT PARTIAL MIXING TODAY TO DIMINISH
THE LLWS THIS AFTERNOON. DESPITE FAIRLY STRONG WINDS THIS
EVENING...WINDS ALOFT WILL BE SO STRONG THAT MORE LLWS IS LIKELY
WITH A 55-60 KNOT FLOW AT 2000 FEET.
A POWERFUL COLD FRONT WILL CROSS THE REGION FROM WEST TO EAST TONIGHT.
THIS FRONT COULD BE ACCOMPANIED BY A LINE OF THUNDERSTORMS CAPABLE
OF PRODUCING IFR/LOW MVFR CONDITIONS AND SURFACE WIND GUSTS TO 50
KNOTS. FOLLOWING THE FRONTAL PASSAGE...EXPECT WINDS TO VEER TO
SOUTHWESTERLY AND INCREASE...PRODUCING A MORE PROLONGED ROUND OF
40-50 KNOT WIND GUSTS THAT WILL LAST INTO MONDAY MORNING.
OTHERWISE...DRY WEATHER WILL RETURN FOLLOWING THE FROPA AS STRONG
DRY SLOTTING OVERSPREADS THE REGION ALOFT...THOUGH SOME MVFR TO
LOW VFR CIGS MAY LINGER.
OUTLOOK...
MONDAY...STRONG WINDS IN THE MORNING...OTHERWISE MVFR/VFR WITH A
CHANCE OF SHOWERS EAST OF THE LAKES IN THE AFTERNOON.
TUESDAY...VFR WITH LOCAL MVFR IN LIGHT LAKE EFFECT SNOW SHOWERS
SOUTHEAST OF THE LAKES.
WEDNESDAY AND THURSDAY...VFR.
&&
.MARINE...
SOUTHERLY WINDS WILL PERSIST TODAY...AND WILL BE GUSTY IN SOME
LOCATIONS...PARTICULARLY ON LAKE ERIE. THIS INCREASING SOUTHERLY
FLOW WILL ALSO BUILD WAVES ON EASTERN LAKE ONTARIO DUE TO THE
LONGER FETCH.
THE MAIN PERIOD OF CONCERN WILL BE THIS EVENING THROUGH MONDAY WHEN
GALE FORCE WINDS ARE A NEAR CERTAINTY ON BOTH LAKES. LOW PRESSURE
DEEPENING TO 970 MB SOUTH OF JAMES BAY LATE TONIGHT WILL PRODUCE A
PERIOD OF SOLID GALES ON THE LAKES TONIGHT AND MONDAY. IT WILL BE A
BIT MORE MARGINAL ON THE RIVERS...BUT THE SHEAR STRENGTH OF THE LOW
AND STRONG WINDS ALOFT JUSTIFY GALES ON THE RIVERS TOO.
WINDS WILL GRADUALLY DIMINISH MONDAY NIGHT AND TUESDAY AS THE FLOW
BECOMES NORTHWESTERLY.
&&
.TIDES/COASTAL FLOODING...
A RAPIDLY DEEPENING AREA OF LOW PRESSURE MOVING FROM THE CENTRAL
LAKES TOWARDS WESTERN QUEBEC WILL FOLLOW A FAVORABLE PATH TO
PRODUCE STRONG SOUTHWEST WINDS ON LAKE ERIE AND PUSH RISING WATER
TO THE NORTHEAST END OF THE LAKE.
WINDS WILL SHIFT FROM SOUTHERLY TO SOUTHWESTERLY FOLLOWING A
STRONG COLD FRONT LATE SUNDAY EVENING. NORMALLY THIS SCENARIO
GIVEN THE FORECAST WIND SPEEDS WOULD NOT ALLOW THE LAKE LEVEL TO
QUITE REACH FLOOD STAGE...WITH MODEL GUIDANCE SUGGESTING A PEAK
AROUND 5 FEET. BUT THERE IS THE POTENTIAL FOR A SQUALL LINE ALONG
THE COLD FRONT. SQUALL LINE DRIVEN SEICHE EVENTS ARE NOT AS COMMON
AS SYNOPTICALLY DRIVEN...BUT IF THE SQUALL LINE IS STRONG ENOUGH
IT MAY ENHANCE THE SEICHE AND PUSH THE WATER LEVEL AT BUFFALO TO
NEAR THE FLOOD STAGE OF 8 FEET ABOVE LOW WATER DATUM. CONFIDENCE
IN LAKESHORE FLOODING REMAINS MARGINAL GIVEN THE FAIRLY INFREQUENT
NATURE OF SIMILAR EVENTS. WITH THIS IN MIND...A LAKESHORE FLOOD
WATCH REMAINS IN EFFECT FOR TONIGHT INTO EARLY MONDAY MORNING.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...HIGH WIND WARNING FROM 4 PM THIS AFTERNOON TO 1 PM EST MONDAY
FOR NYZ019-085.
LAKESHORE FLOOD WATCH FROM THIS EVENING THROUGH MONDAY MORNING
FOR NYZ010-019-085.
HIGH WIND WARNING FROM 7 PM THIS EVENING TO 4 PM EST MONDAY
FOR NYZ007-008.
HIGH WIND WATCH FROM THIS EVENING THROUGH MONDAY AFTERNOON FOR
NYZ004>006.
HIGH WIND WARNING FROM 7 PM THIS EVENING TO 1 PM EST MONDAY
FOR NYZ001>003-010-011.
HIGH WIND WATCH FROM THIS EVENING THROUGH MONDAY AFTERNOON FOR
NYZ012>014-020-021.
MARINE...GALE WARNING FROM 7 PM THIS EVENING TO 4 PM EST MONDAY FOR
LEZ020-040-041.
SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR
LEZ040-041.
GALE WARNING FROM 7 PM THIS EVENING TO 4 PM EST
MONDAY FOR LOZ030.
SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR
LOZ043>045.
GALE WARNING FROM 7 PM THIS EVENING TO 7 PM EST MONDAY FOR
LOZ043>045-063>065.
GALE WARNING FROM 10 PM THIS EVENING TO 4 PM EST MONDAY
FOR LOZ042-062.
GALE WARNING FROM 1 AM TO 7 PM EST MONDAY FOR SLZ022-
024.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL
SHORT TERM...THOMAS
LONG TERM...THOMAS/TJP
AVIATION...APFFEL/JJR
MARINE...APFFEL/THOMAS
TIDES/COASTAL FLOODING...HITCHCOCK/APFFEL
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1033 AM EST SUN NOV 17 2013
.SYNOPSIS...
LOW PRESSURE OVER THE PLAINS STATES WILL DEEPEN RAPIDLY AS IT
MOVES NORTHEAST TODAY REACHING NORTHERN LAKE MICHIGAN BY THIS
EVENING AND INTO QUEBEC ON MONDAY. THIS WILL PUSH A STRONG COLD
FRONT ACROSS THE AREA THIS EVENING. HIGH PRESSURE WILL MOVE EAST
OUT OF THE SOUTHERN PLAINS STATES INTO THE OHIO VALLEY BY TUESDAY
AND THEN OFF THE EAST COAST ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
REMOVED THUNDER ACROSS NORTH CENTRAL OHIO AND POINTS EAST UNTIL
VERY LATE AFTERNOON/EVENING. WHILE I CANNOT RULE OUT THUNDER...
WOULD LIKE TO MAKE THE THUNDER AND WIND WITH THE FRONT MORE OF THE
FOCAL POINT OF THE FORECAST. TOUGH TO DO IN THESE DAYS OF
AUTOMATED TEXT FORMATTERS...SO NOT SURE EXACTLY WHAT THE WORDING
WILL SAY. BETTER CHANCE FOR THUNDER AT ANY TIME IN THE DRY SLOT
THAT IS CREEPING ACROSS NORTHWEST OHIO. SORT OF LOOKS LIKE
OKLAHOMA IN THE SPRING TIME...HMMM.
NO OTHER SIGNIFICANT CHANGES TO THE FORECAST. DID NUDGE UP HIGH
TEMPERATURES A COUPLE OF DEGREES ACROSS NW OHIO AND PARTS OF NORTH
CENTRAL OHIO WHERE THERE WILL NOT BE AS MANY SHOWERS. RECORD HIGH
IN TOLEDO IS 71 AND WE WILL TAKE A RUN AT IT. 72 AT CLE IS
POTENTIALLY WITHIN REACH.
RELEVANT EARLY MORNING UPDATED DISCUSSION...
SHOWERS CONTINUE TO MOVE EAST AND OUT OF THE AREA AT THIS TIME.
CELLULAR CONVECTION CONTINUES TO MOVE INTO EXTREME NORTHWEST OHIO
AND SOUTHERN LOWER MICHIGAN. THE WATER VAPOR PLUME IS ALSO PUSHING
EAST ALLOWING FOR SOME DRIER AIR TO MOVE EAST AND ALLOW FOR A
BREAK IN THE ACTION. LATEST HRRR MODEL SHOWS MASSIVE SQUALL LINE
DEVELOPING OVER ILLINOIS AND RAPIDLY INTENSIFIES AS IT MOVES EAST
TOWARD OHIO. TIMING WOULD PUT THE LINE AT TOLEDO AND FINDLAY AT
22Z AND TO CLEVELAND AND MANSFIELD BY ABOUT 00Z AND FINALLY TO
ERIE AND YOUNGSTOWN BY 02Z OR SO. SO THE WAIT BEGINS. STAY TUNED.
PREVIOUS DISCUSSION...
THE LONG ANTICIPATED SEVERE WEATHER THREAT DAY HAS ARRIVED. TWO LOW
PRESSURE SYSTEMS IN THE UPPER MIDWEST ARE BEGINNING TO MERGE AND
INTENSIFY THIS MORNING.
SOUTHERLY FLOW HAS INCREASED ACROSS THE FORECAST AREA AND THIS WILL
BE THE BEGINNING OF THE STRENGTHENING WIND FLOW THROUGHOUT THE DAY.
MODERATELY STRONG LOW LEVEL JET WILL REMAIN PERSISTENT OVER THE
FORECAST AREA TODAY AND WITH THE WARM AIR ADVECTION...SOME OF THE
STRONGER WINDS WILL MIX DOWN TO THE SURFACE. SO...WILL GO AHEAD AND
ISSUE A WIND ADVISORY FOR THE ENTIRE AREA BUT WILL BE FOR MAINLY
LATER THIS EVENING INTO TONIGHT SINCE THE STRONGEST WINDS WILL TAKE
PLACE AFTER THE COLD FRONTAL PASSAGE.
60 TO 70 KNOT SPEED MAXIMUM AT 850 MB WILL POSE A PROBLEM AS
CONVECTION DEVELOPS LATER THIS MORNING INTO THE AFTERNOON HOURS. THE
STRONGER WINDS COULD BE FORCED TO THE SURFACE IN THE THUNDERSTORMS
AND PRODUCE WIDESPREAD WIND DAMAGE. LATEST STORM PREDICTION CENTER
OUTLOOK CONTINUES TO HIGHLIGHT A MODERATE RISK FOR SEVERE
THUNDERSTORMS ACROSS THE AREA TODAY. THERE IS A HIGH RISK JUST WEST
OF THE FORECAST AREA.
EVEN THOUGH THE MAIN THREATS WILL BE THE STRONG DAMAGING
WINDS...LATEST MODEL SOUNDING HODOGRAPHS INDICATE SOME FAIRLY HIGH
LEVELS OF HELICITY...ESPECIALLY ACROSS AREAS FROM CLEVELAND TO AKRON
CANTON WEST. I CANT RULE OUT THE POTENTIAL FOR ANY THUNDERSTORMS
THAT DEVELOP THAT THEY COULD BEGIN TO ROTATE RATHER QUICKLY AND
PRODUCE TORNADOES. TEMPERATURE DEW POINT SPREADS ARE PROGGED TO BE
AT OR BELOW THE 5 DEGREE THRESHOLD AND THIS IS ONE KEY INGREDIENT
FOR TORNADOES TO DEVELOP.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
THE SEVERE WEATHER THREAT WILL NOT BE OVER TONIGHT. THE COLD FRONT
AND POTENTIAL SQUALL LINE IS EXPECTED TO MOVE THROUGH THE AREA THIS
EVENING AND THIS IS WHEN WE HAVE THE HIGHEST THREAT FOR WIDESPREAD
WIND DAMAGE. ONE FACTOR IS WE WILL BE LOSING THE DAY TIME HEATING
AND THIS MAY HELP TO STABILIZE THINGS A BIT.
AS THE COLD FRONT SHIFTS EAST...COLD AIR ADVECTION WILL TAKE PLACE
AND ALLOW WINDS TO MIX DOWN TO THE SURFACE. WILL HOIST A WIND
ADVISORY FOR TONIGHT DUE TO THE POST FRONTAL WINDS EXPECTED.
AS THE STRONG LOW PRESSURE SYSTEM MOVES RATHER QUICKLY TO THE
NORTHEAST...WINDS ARE EXPECTED TO DIMINISH FAIRLY QUICKLY MONDAY
INTO TUESDAY.
CYCLONIC FLOW AROUND THE BACK SIDE OF THE LOW AND IN ADVANCE OF THE
NEXT HIGH PRESSURE WILL CAUSE SHOWERS TO CONTINUE OVER THE EXTREME
NORTHEAST PORTION OF THE FORECAST AREA. OTHERWISE...DRIER AIR WILL
BEGIN TO RETURN BACK TO THE REGION ON MONDAY. THE COLD AIR ADVECTION
WILL LIKELY PRODUCE SOME LAKE EFFECT RAIN AND SNOW SHOWERS OVER THE
NORTHEAST MONDAY NIGHT AND TUESDAY. THE HIGH WILL BUILD IN ACROSS
THE OHIO VALLEY AND SHIFT THE FLOW AWAY FROM THE LAKE ENDING THE
LAKE EFFECT THREAT. OTHERWISE...FAIR WEATHER IS EXPECTED ACROSS THE
REST OF THE FORECAST AREA MONDAY INTO TUESDAY AND OVER ALL AREAS
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT.
THE COLD FRONT WILL RESULT IN COLD AIR ADVECTION AND PLUNGE
TEMPERATURES BACK TO NEAR NORMAL IN THE 40S FOR HIGHS AND OVERNIGHT
LOWS IN THE 20S TO LOWER 30S.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
NOT MANY CHANGES TO THE LONG TERM TODAY. THE NEW GUIDANCE CONTINUES
TO SHOW THE POSSIBILITY OF WARM AIR ADVECTION SHOWERS ON
THURSDAY...ESPECIALLY IN THE WEST. UNSETTLED WEATHER WILL THEN
CONTINUE INTO NEXT WEEKEND AS A SERIES OF FRONTAL SYSTEMS AFFECTS
THE REGION. IT APPEARS BEST CHANCES FOR PRECIP WILL BE FRIDAY NIGHT
INTO SATURDAY AS A WAVE MOVES ACROSS THE OHIO VALLEY. MOST OF THE
PRECIP SHOULD BE LIQUID ALTHOUGH MIXED RAIN AND SNOW COULD OCCUR
EARLY SATURDAY. TEMPS DURING THE PERIOD WILL BE SEASONABLE AND HAVE
STAYED FAIRLY CLOSE TO GUIDANCE.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
A LARGE AREA OF SHOWERS REMAINS OVER THE EASTERN HALF OF THE AREA
THIS MORNING AND IS EXPECTED TO EXIT TO THE EAST IN A COUPLE OF
HOURS. MOST LOCATIONS REMAIN VFR BUT SOME PATCHY MVFR IS BEING
REPORTED. A LOT OF MVFR CIGS TO THE WEST AND EXPECT ALL AREAS TO
DIP TO MVFR CIGS BY MIDDAY. SHOWER ACTIVITY TO THE WEST OF THE
MAIN AREA WILL BE SCATTERED IN NATURE THIS MORNING. EXPECT MUCH OF
THE AFTERNOON TO BE DRY WITH A FEW PEAKS OF SUNSHINE POSSIBLE. NEW
GUIDANCE COMING IN CONTINUES TO SHOW A SQUALL LINE DEVELOPING
OVER NW OH TOWARD EVENING. CONFIDENCE IN THIS SCENARIO IS
UNUSUALLY HIGH. THIS LINE SHOULD REACH KTOL AND KFDY AROUND SUNSET
AND IS THEN EXPECTED TO RACE EAST ACROSS THE REMAINDER OF THE AREA
THIS EVENING. THE LINE COULD MOVE AS FAST AS 45 TO 50 KNOTS AT
TIMES. VERY STRONG WINDS ARE FORECAST JUST ABOVE THE SURFACE AND
ANY SIGNIFICANT RAIN WILL BRING THESE STRONG WINDS DOWN TO THE
SURFACE. AS A RESULT HAVE CONTINUED TO HIT THE WINDS PRETTY HARD
IN THE NEW FORECAST. A COLD FRONT WILL FOLLOW THE SQUALL LINE
ACROSS THE AREA THIS EVENING AND EXPECT CIGS TO LIFT TO VFR AND
THEN DISSIPATE FROM WEST TO EAST OVERNIGHT. WINDS TODAY WILL BE
MAINLY FROM THE SOUTH WITH GUSTS INCREASING TO 35 KNOTS THIS
AFTERNOON. THE FLOW BEHIND THE FRONT WILL BE WSW AND GUSTS COULD
GET TO 40 KNOTS OVERNIGHT.
OUTLOOK...NON-VFR CONDITIONS WILL CONTINUE SUNDAY NIGHT INTO
MONDAY WITH A FEW SHRA. A FEW SHSN MONDAY NIGHT...MAINLY ACROSS NE
OH/NW PA. CONDITIONS IMPROVING TO VFR FROM WEST TO EAST TUESDAY.
&&
.MARINE...
NO CHANGES TO THE HEADLINES ON THE LAKE TODAY. THE GALE STILL LOOKS
GOOD FOR LATE TODAY AND TONIGHT. STILL EXPECTING A SQUALL LINE TO
MOVE ACROSS THE LAKE THIS EVENING AND WIND GUSTS COULD APPROACH 50
KNOTS. WINDS WILL BECOME WESTERLY BEHIND THE COLD FRONT RESPONSIBLE
FOR THE SQUALL LINE. SPEEDS SHOULD GRADUALLY DIMINISH ON MONDAY AND
EXPECT A PROLONGED PERIOD OF SMALL CRAFT ADVISORIES ONCE THE GALE
COMES DOWN. LOCAL GUIDANCE ALSO SHOWS WATER LEVELS MAKING A RUN FOR
THE CRITICAL MARK LATE TONIGHT. WILL SEE HOW THINGS DEVELOP BUT
LATER SHIFTS MAY NEED TO GO WITH A LOW WATER ADVISORY. THE FLOW
WILL BECOME NW ON MONDAY AS HIGH PRESSURE BEGINS TO BUILD IN FROM
THE WEST. A SURFACE RIDGE WILL EVENTUALLY MOVE EAST OF THE LAKE
TUESDAY NIGHT ALLOWING THE FLOW TO BECOME SOUTHERLY. SOUTH TO
SOUTHWEST FLOW WILL THEN CONTINUE TILL A COLD FRONT CROSSES THE LAKE
AT THE VERY END OF THE PERIOD.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...WIND ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST MONDAY FOR
OHZ003-006>014-017>023-027>033-036>038-047-089.
PA...WIND ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST MONDAY FOR
PAZ001>003.
MARINE...GALE WARNING FROM 6 PM THIS EVENING TO 4 PM EST MONDAY FOR
LEZ061-142>149-162>169.
&&
$$
SYNOPSIS...KOSARIK/LOMBARDY
NEAR TERM...KOSARIK/LOMBARDY
SHORT TERM...LOMBARDY
LONG TERM...KUBINA
AVIATION...KUBINA
MARINE...KUBINA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1020 AM EST SUN NOV 17 2013
.SYNOPSIS...
LOW PRESSURE OVER THE PLAINS STATES WILL DEEPEN RAPIDLY AS IT
MOVES NORTHEAST TODAY REACHING NORTHERN LAKE MICHIGAN BY THIS
EVENING AND INTO QUEBEC ON MONDAY. THIS WILL PUSH A STRONG COLD
FRONT ACROSS THE AREA THIS EVENING. HIGH PRESSURE WILL MOVE EAST
OUT OF THE SOUTHERN PLAINS STATES INTO THE OHIO VALLEY BY TUESDAY
AND THEN OFF THE EAST COAST ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
REMOVED THUNDER ACROSS NORTH CENTRAL OHIO AND POINTS EAST UNTIL
VERY LATE AFTERNOON/EVENING. WHILE I CANNOT RULE OUT THUNDER...
WOULD LIKE TO MAKE THE THUNDER AND WIND WITH THE FRONT MORE OF THE
FOCAL POINT OF THE FORECAST. TOUGH TO DO IN THESE DAYS OF
AUTOMATED TEXT FORMATTERS...SO NOT SURE EXACTLY WHAT THE WORDING
WILL SAY. THUNDER FORECAST ON THE EAST FOR MIDDAY AND EARLY
AFTERNOON. BETTER CHANCE FOR THUNDER AT ANY TIME IN THE DRY SLOT
THAT IS CREEPING ACROSS NORTHWEST OHIO. SORT OF LOOKS LIKE
OKLAHOMA IN THE SPRING TIME...HMMM. NO OTHER SIGNIFICANT CHANGES
TO THE FORECAST. DID NUDGE UP HIGH TEMPERATURES A COUPLE OF DEGREES
ACROSS NW OHIO AND PARTS OF NORTH CENTRAL OHIO WHERE THERE WILL
NOT BE AS MANY SHOWERS. RECORD HIGH IN TOLEDO IS 71 AND WE WILL
TAKE A RUN AT IT. 72 AT CLE IS POTENTIALLY WITHIN REACH.
RELEVANT EARLY MORNING UPDATED DISCUSSION...
SHOWERS CONTINUE TO MOVE EAST AND OUT OF THE AREA AT THIS TIME.
CELLULAR CONVECTION CONTINUES TO MOVE INTO EXTREME NORTHWEST OHIO
AND SOUTHERN LOWER MICHIGAN. THE WATER VAPOR PLUME IS ALSO PUSHING
EAST ALLOWING FOR SOME DRIER AIR TO MOVE EAST AND ALLOW FOR A
BREAK IN THE ACTION. LATEST HRRR MODEL SHOWS MASSIVE SQUALL LINE
DEVELOPING OVER ILLINOIS AND RAPIDLY INTENSIFIES AS IT MOVES EAST
TOWARD OHIO. TIMING WOULD PUT THE LINE AT TOLEDO AND FINDLAY AT
22Z AND TO CLEVELAND AND MANSFIELD BY ABOUT 00Z AND FINALLY TO
ERIE AND YOUNGSTOWN BY 02Z OR SO. SO THE WAIT BEGINS. STAY TUNED.
PREVIOUS DISCUSSION...
THE LONG ANTICIPATED SEVERE WEATHER THREAT DAY HAS ARRIVED. TWO LOW
PRESSURE SYSTEMS IN THE UPPER MIDWEST ARE BEGINNING TO MERGE AND
INTENSIFY THIS MORNING.
SOUTHERLY FLOW HAS INCREASED ACROSS THE FORECAST AREA AND THIS WILL
BE THE BEGINNING OF THE STRENGTHENING WIND FLOW THROUGHOUT THE DAY.
MODERATELY STRONG LOW LEVEL JET WILL REMAIN PERSISTENT OVER THE
FORECAST AREA TODAY AND WITH THE WARM AIR ADVECTION...SOME OF THE
STRONGER WINDS WILL MIX DOWN TO THE SURFACE. SO...WILL GO AHEAD AND
ISSUE A WIND ADVISORY FOR THE ENTIRE AREA BUT WILL BE FOR MAINLY
LATER THIS EVENING INTO TONIGHT SINCE THE STRONGEST WINDS WILL TAKE
PLACE AFTER THE COLD FRONTAL PASSAGE.
60 TO 70 KNOT SPEED MAXIMUM AT 850 MB WILL POSE A PROBLEM AS
CONVECTION DEVELOPS LATER THIS MORNING INTO THE AFTERNOON HOURS. THE
STRONGER WINDS COULD BE FORCED TO THE SURFACE IN THE THUNDERSTORMS
AND PRODUCE WIDESPREAD WIND DAMAGE. LATEST STORM PREDICTION CENTER
OUTLOOK CONTINUES TO HIGHLIGHT A MODERATE RISK FOR SEVERE
THUNDERSTORMS ACROSS THE AREA TODAY. THERE IS A HIGH RISK JUST WEST
OF THE FORECAST AREA.
EVEN THOUGH THE MAIN THREATS WILL BE THE STRONG DAMAGING
WINDS...LATEST MODEL SOUNDING HODOGRAPHS INDICATE SOME FAIRLY HIGH
LEVELS OF HELICITY...ESPECIALLY ACROSS AREAS FROM CLEVELAND TO AKRON
CANTON WEST. I CANT RULE OUT THE POTENTIAL FOR ANY THUNDERSTORMS
THAT DEVELOP THAT THEY COULD BEGIN TO ROTATE RATHER QUICKLY AND
PRODUCE TORNADOES. TEMPERATURE DEW POINT SPREADS ARE PROGGED TO BE
AT OR BELOW THE 5 DEGREE THRESHOLD AND THIS IS ONE KEY INGREDIENT
FOR TORNADOES TO DEVELOP.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
THE SEVERE WEATHER THREAT WILL NOT BE OVER TONIGHT. THE COLD FRONT
AND POTENTIAL SQUALL LINE IS EXPECTED TO MOVE THROUGH THE AREA THIS
EVENING AND THIS IS WHEN WE HAVE THE HIGHEST THREAT FOR WIDESPREAD
WIND DAMAGE. ONE FACTOR IS WE WILL BE LOSING THE DAY TIME HEATING
AND THIS MAY HELP TO STABILIZE THINGS A BIT.
AS THE COLD FRONT SHIFTS EAST...COLD AIR ADVECTION WILL TAKE PLACE
AND ALLOW WINDS TO MIX DOWN TO THE SURFACE. WILL HOIST A WIND
ADVISORY FOR TONIGHT DUE TO THE POST FRONTAL WINDS EXPECTED.
AS THE STRONG LOW PRESSURE SYSTEM MOVES RATHER QUICKLY TO THE
NORTHEAST...WINDS ARE EXPECTED TO DIMINISH FAIRLY QUICKLY MONDAY
INTO TUESDAY.
CYCLONIC FLOW AROUND THE BACK SIDE OF THE LOW AND IN ADVANCE OF THE
NEXT HIGH PRESSURE WILL CAUSE SHOWERS TO CONTINUE OVER THE EXTREME
NORTHEAST PORTION OF THE FORECAST AREA. OTHERWISE...DRIER AIR WILL
BEGIN TO RETURN BACK TO THE REGION ON MONDAY. THE COLD AIR ADVECTION
WILL LIKELY PRODUCE SOME LAKE EFFECT RAIN AND SNOW SHOWERS OVER THE
NORTHEAST MONDAY NIGHT AND TUESDAY. THE HIGH WILL BUILD IN ACROSS
THE OHIO VALLEY AND SHIFT THE FLOW AWAY FROM THE LAKE ENDING THE
LAKE EFFECT THREAT. OTHERWISE...FAIR WEATHER IS EXPECTED ACROSS THE
REST OF THE FORECAST AREA MONDAY INTO TUESDAY AND OVER ALL AREAS
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT.
THE COLD FRONT WILL RESULT IN COLD AIR ADVECTION AND PLUNGE
TEMPERATURES BACK TO NEAR NORMAL IN THE 40S FOR HIGHS AND OVERNIGHT
LOWS IN THE 20S TO LOWER 30S.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
NOT MANY CHANGES TO THE LONG TERM TODAY. THE NEW GUIDANCE CONTINUES
TO SHOW THE POSSIBILITY OF WARM AIR ADVECTION SHOWERS ON
THURSDAY...ESPECIALLY IN THE WEST. UNSETTLED WEATHER WILL THEN
CONTINUE INTO NEXT WEEKEND AS A SERIES OF FRONTAL SYSTEMS AFFECTS
THE REGION. IT APPEARS BEST CHANCES FOR PRECIP WILL BE FRIDAY NIGHT
INTO SATURDAY AS A WAVE MOVES ACROSS THE OHIO VALLEY. MOST OF THE
PRECIP SHOULD BE LIQUID ALTHOUGH MIXED RAIN AND SNOW COULD OCCUR
EARLY SATURDAY. TEMPS DURING THE PERIOD WILL BE SEASONABLE AND HAVE
STAYED FAIRLY CLOSE TO GUIDANCE.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
A LARGE AREA OF SHOWERS REMAINS OVER THE EASTERN HALF OF THE AREA
THIS MORNING AND IS EXPECTED TO EXIT TO THE EAST IN A COUPLE OF
HOURS. MOST LOCATIONS REMAIN VFR BUT SOME PATCHY MVFR IS BEING
REPORTED. A LOT OF MVFR CIGS TO THE WEST AND EXPECT ALL AREAS TO
DIP TO MVFR CIGS BY MIDDAY. SHOWER ACTIVITY TO THE WEST OF THE
MAIN AREA WILL BE SCATTERED IN NATURE THIS MORNING. EXPECT MUCH OF
THE AFTERNOON TO BE DRY WITH A FEW PEAKS OF SUNSHINE POSSIBLE. NEW
GUIDANCE COMING IN CONTINUES TO SHOW A SQUALL LINE DEVELOPING
OVER NW OH TOWARD EVENING. CONFIDENCE IN THIS SCENARIO IS
UNUSUALLY HIGH. THIS LINE SHOULD REACH KTOL AND KFDY AROUND SUNSET
AND IS THEN EXPECTED TO RACE EAST ACROSS THE REMAINDER OF THE AREA
THIS EVENING. THE LINE COULD MOVE AS FAST AS 45 TO 50 KNOTS AT
TIMES. VERY STRONG WINDS ARE FORECAST JUST ABOVE THE SURFACE AND
ANY SIGNIFICANT RAIN WILL BRING THESE STRONG WINDS DOWN TO THE
SURFACE. AS A RESULT HAVE CONTINUED TO HIT THE WINDS PRETTY HARD
IN THE NEW FORECAST. A COLD FRONT WILL FOLLOW THE SQUALL LINE
ACROSS THE AREA THIS EVENING AND EXPECT CIGS TO LIFT TO VFR AND
THEN DISSIPATE FROM WEST TO EAST OVERNIGHT. WINDS TODAY WILL BE
MAINLY FROM THE SOUTH WITH GUSTS INCREASING TO 35 KNOTS THIS
AFTERNOON. THE FLOW BEHIND THE FRONT WILL BE WSW AND GUSTS COULD
GET TO 40 KNOTS OVERNIGHT.
OUTLOOK...NON-VFR CONDITIONS WILL CONTINUE SUNDAY NIGHT INTO
MONDAY WITH A FEW SHRA. A FEW SHSN MONDAY NIGHT...MAINLY ACROSS NE
OH/NW PA. CONDITIONS IMPROVING TO VFR FROM WEST TO EAST TUESDAY.
&&
.MARINE...
NO CHANGES TO THE HEADLINES ON THE LAKE TODAY. THE GALE STILL LOOKS
GOOD FOR LATE TODAY AND TONIGHT. STILL EXPECTING A SQUALL LINE TO
MOVE ACROSS THE LAKE THIS EVENING AND WIND GUSTS COULD APPROACH 50
KNOTS. WINDS WILL BECOME WESTERLY BEHIND THE COLD FRONT RESPONSIBLE
FOR THE SQUALL LINE. SPEEDS SHOULD GRADUALLY DIMINISH ON MONDAY AND
EXPECT A PROLONGED PERIOD OF SMALL CRAFT ADVISORIES ONCE THE GALE
COMES DOWN. LOCAL GUIDANCE ALSO SHOWS WATER LEVELS MAKING A RUN FOR
THE CRITICAL MARK LATE TONIGHT. WILL SEE HOW THINGS DEVELOP BUT
LATER SHIFTS MAY NEED TO GO WITH A LOW WATER ADVISORY. THE FLOW
WILL BECOME NW ON MONDAY AS HIGH PRESSURE BEGINS TO BUILD IN FROM
THE WEST. A SURFACE RIDGE WILL EVENTUALLY MOVE EAST OF THE LAKE
TUESDAY NIGHT ALLOWING THE FLOW TO BECOME SOUTHERLY. SOUTH TO
SOUTHWEST FLOW WILL THEN CONTINUE TILL A COLD FRONT CROSSES THE LAKE
AT THE VERY END OF THE PERIOD.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...WIND ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST MONDAY FOR
OHZ003-006>014-017>023-027>033-036>038-047-089.
PA...WIND ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST MONDAY FOR
PAZ001>003.
MARINE...GALE WARNING FROM 6 PM THIS EVENING TO 4 PM EST MONDAY FOR
LEZ061-142>149-162>169.
&&
$$
SYNOPSIS...KOSARIK/LOMBARDY
NEAR TERM...KOSARIK/LOMBARDY
SHORT TERM...LOMBARDY
LONG TERM...KUBINA
AVIATION...KUBINA
MARINE...KUBINA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
642 AM EST SUN NOV 17 2013
.SYNOPSIS...
A DOUBLED BARRELED LOW PRESSURE FROM SOUTHERN MINNESOTA TO WESTERN
KANSAS WILL MOVE TO NORTHERN LAKE MICHIGAN BY THIS EVENING.
MEANWHILE...THE LOW PRESSURE WILL DEEPEN RAPIDLY AS IT MOVES INTO
WEST CENTRAL QUEBEC BY MONDAY AFTERNOON. A STRONG COLD FRONT WILL
SWEEP EAST ACROSS THE AREA TONIGHT. HIGH PRESSURE WILL MOVE EAST OUT
OF THE SOUTHERN PLAINS STATES INTO THE OHIO VALLEY BY TUESDAY AND
THEN OFF THE EAST COAST ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SHOWERS CONTINUE TO MOVE EAST AND OUT OF THE AREA AT THIS TIME.
CELLULAR CONVECTION CONTINUES TO MOVE INTO EXTREME NORTHWEST OHIO
AND SOUTHERN LOWER MICHIGAN. THE WATER VAPOR PLUME IS ALSO PUSHING
EAST ALLOWING FOR SOME DRIER AIR TO MOVE EAST AND ALLOW FOR A
BREAK IN THE ACTION. LATEST HRRR MODEL SHOWS MASSIVE SQUALL LINE
DEVELOPING OVER ILLINOIS AND RAPIDLY INTENSIFIES AS IT MOVES EAST
TOWARD OHIO. TIMING WOULD PUT THE LINE AT TOLEDO AND FINDLAY AT
22Z AND TO CLEVELAND AND MANSFIELD BY ABOUT 00Z AND FINALLY TO
ERIE AND YOUNGSTOWN BY 02Z OR SO. SO THE WAIT BEGINS. STAY TUNED.
PREVIOUS DISCUSSION...
THE LONG ANTICIPATED SEVERE WEATHER THREAT DAY HAS ARRIVED. TWO LOW
PRESSURE SYSTEMS IN THE UPPER MIDWEST ARE BEGINNING TO MERGE AND
INTENSIFY THIS MORNING.
SOUTHERLY FLOW HAS INCREASED ACROSS THE FORECAST AREA AND THIS WILL
BE THE BEGINNING OF THE STRENGTHENING WIND FLOW THROUGHOUT THE DAY.
MODERATELY STRONG LOW LEVEL JET WILL REMAIN PERSISTENT OVER THE
FORECAST AREA TODAY AND WITH THE WARM AIR ADVECTION...SOME OF THE
STRONGER WINDS WILL MIX DOWN TO THE SURFACE. SO...WILL GO AHEAD AND
ISSUE A WIND ADVISORY FOR THE ENTIRE AREA BUT WILL BE FOR MAINLY
LATER THIS EVENING INTO TONIGHT SINCE THE STRONGEST WINDS WILL TAKE
PLACE AFTER THE COLD FRONTAL PASSAGE.
60 TO 70 KNOT SPEED MAXIMUM AT 850 MB WILL POSE A PROBLEM AS
CONVECTION DEVELOPS LATER THIS MORNING INTO THE AFTERNOON HOURS. THE
STRONGER WINDS COULD BE FORCED TO THE SURFACE IN THE THUNDERSTORMS
AND PRODUCE WIDESPREAD WIND DAMAGE. LATEST STORM PREDICTION CENTER
OUTLOOK CONTINUES TO HIGHLIGHT A MODERATE RISK FOR SEVERE
THUNDERSTORMS ACROSS THE AREA TODAY. THERE IS A HIGH RISK JUST WEST
OF THE FORECAST AREA.
EVEN THOUGH THE MAIN THREATS WILL BE THE STRONG DAMAGING
WINDS...LATEST MODEL SOUNDING HODOGRAPHS INDICATE SOME FAIRLY HIGH
LEVELS OF HELICITY...ESPECIALLY ACROSS AREAS FROM CLEVELAND TO AKRON
CANTON WEST. I CANT RULE OUT THE POTENTIAL FOR ANY THUNDERSTORMS
THAT DEVELOP THAT THEY COULD BEGIN TO ROTATE RATHER QUICKLY AND
PRODUCE TORNADOES. TEMPERATURE DEW POINT SPREADS ARE PROGGED TO BE
AT OR BELOW THE 5 DEGREE THRESHOLD AND THIS IS ONE KEY INGREDIENT
FOR TORNADOES TO DEVELOP.
LOOKING AT THE LATEST WATER VAPOR IMAGERY SHOWS AN EXTENSIVE AREA OF
MOISTURE STREAMING NORTH ACROSS THE FORECAST AREA AT THIS TIME.
HOWEVER...JUST WEST OF THE AREA...THIS MOISTURE PLUME DIMINISHES AND
THIS IS RESULTING IN CLEARING SKIES WELL AHEAD OF THE COLD FRONT.
WITH THIS IN MIND...I AM CONCERNED THAT WE WILL SEE A LOT MORE SUN
THAN I CURRENTLY HAVE IN THE FORECAST. IF THIS IS THE CASE...THEN
CURRENT FORECAST TEMPERATURES COULD BE TOO LOW AND THEREFORE WILL
SEE EVEN GREATER INSTABILITY DEVELOP. THIS WILL HAVE TO BE WATCHED
CLOSELY TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
THE SEVERE WEATHER THREAT WILL NOT BE OVER TONIGHT. THE COLD FRONT
AND POTENTIAL SQUALL LINE IS EXPECTED TO MOVE THROUGH THE AREA THIS
EVENING AND THIS IS WHEN WE HAVE THE HIGHEST THREAT FOR WIDESPREAD
WIND DAMAGE. ONE FACTOR IS WE WILL BE LOSING THE DAY TIME HEATING
AND THIS MAY HELP TO STABILIZE THINGS A BIT.
AS THE COLD FRONT SHIFTS EAST...COLD AIR ADVECTION WILL TAKE PLACE
AND ALLOW WINDS TO MIX DOWN TO THE SURFACE. WILL HOIST A WIND
ADVISORY FOR TONIGHT DUE TO THE POST FRONTAL WINDS EXPECTED.
AS THE STRONG LOW PRESSURE SYSTEM MOVES RATHER QUICKLY TO THE
NORTHEAST...WINDS ARE EXPECTED TO DIMINISH FAIRLY QUICKLY MONDAY
INTO TUESDAY.
CYCLONIC FLOW AROUND THE BACK SIDE OF THE LOW AND IN ADVANCE OF THE
NEXT HIGH PRESSURE WILL CAUSE SHOWERS TO CONTINUE OVER THE EXTREME
NORTHEAST PORTION OF THE FORECAST AREA. OTHERWISE...DRIER AIR WILL
BEGIN TO RETURN BACK TO THE REGION ON MONDAY. THE COLD AIR ADVECTION
WILL LIKELY PRODUCE SOME LAKE EFFECT RAIN AND SNOW SHOWERS OVER THE
NORTHEAST MONDAY NIGHT AND TUESDAY. THE HIGH WILL BUILD IN ACROSS
THE OHIO VALLEY AND SHIFT THE FLOW AWAY FROM THE LAKE ENDING THE
LAKE EFFECT THREAT. OTHERWISE...FAIR WEATHER IS EXPECTED ACROSS THE
REST OF THE FORECAST AREA MONDAY INTO TUESDAY AND OVER ALL AREAS
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT.
THE COLD FRONT WILL RESULT IN COLD AIR ADVECTION AND PLUNGE
TEMPERATURES BACK TO NEAR NORMAL IN THE 40S FOR HIGHS AND OVERNIGHT
LOWS IN THE 20S TO LOWER 30S.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
NOT MANY CHANGES TO THE LONG TERM TODAY. THE NEW GUIDANCE CONTINUES
TO SHOW THE POSSIBILITY OF WARM AIR ADVECTION SHOWERS ON
THURSDAY...ESPECIALLY IN THE WEST. UNSETTLED WEATHER WILL THEN
CONTINUE INTO NEXT WEEKEND AS A SERIES OF FRONTAL SYSTEMS AFFECTS
THE REGION. IT APPEARS BEST CHANCES FOR PRECIP WILL BE FRIDAY NIGHT
INTO SATURDAY AS A WAVE MOVES ACROSS THE OHIO VALLEY. MOST OF THE
PRECIP SHOULD BE LIQUID ALTHOUGH MIXED RAIN AND SNOW COULD OCCUR
EARLY SATURDAY. TEMPS DURING THE PERIOD WILL BE SEASONABLE AND HAVE
STAYED FAIRLY CLOSE TO GUIDANCE.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
A LARGE AREA OF SHOWERS REMAINS OVER THE EASTERN HALF OF THE AREA
THIS MORNING AND IS EXPECTED TO EXIT TO THE EAST IN A COUPLE OF
HOURS. MOST LOCATIONS REMAIN VFR BUT SOME PATCHY MVFR IS BEING
REPORTED. A LOT OF MVFR CIGS TO THE WEST AND EXPECT ALL AREAS TO
DIP TO MVFR CIGS BY MIDDAY. SHOWER ACTIVITY TO THE WEST OF THE
MAIN AREA WILL BE SCATTERED IN NATURE THIS MORNING. EXPECT MUCH OF
THE AFTERNOON TO BE DRY WITH A FEW PEAKS OF SUNSHINE POSSIBLE. NEW
GUIDANCE COMING IN CONTINUES TO SHOW A SQUALL LINE DEVELOPING
OVER NW OH TOWARD EVENING. CONFIDENCE IN THIS SCENARIO IS
UNUSUALLY HIGH. THIS LINE SHOULD REACH KTOL AND KFDY AROUND SUNSET
AND IS THEN EXPECTED TO RACE EAST ACROSS THE REMAINDER OF THE AREA
THIS EVENING. THE LINE COULD MOVE AS FAST AS 45 TO 50 KNOTS AT
TIMES. VERY STRONG WINDS ARE FORECAST JUST ABOVE THE SURFACE AND
ANY SIGNIFICANT RAIN WILL BRING THESE STRONG WINDS DOWN TO THE
SURFACE. AS A RESULT HAVE CONTINUED TO HIT THE WINDS PRETTY HARD
IN THE NEW FORECAST. A COLD FRONT WILL FOLLOW THE SQUALL LINE
ACROSS THE AREA THIS EVENING AND EXPECT CIGS TO LIFT TO VFR AND
THEN DISSIPATE FROM WEST TO EAST OVERNIGHT. WINDS TODAY WILL BE
MAINLY FROM THE SOUTH WITH GUSTS INCREASING TO 35 KNOTS THIS
AFTERNOON. THE FLOW BEHIND THE FRONT WILL BE WSW AND GUSTS COULD
GET TO 40 KNOTS OVERNIGHT.
OUTLOOK...NON-VFR CONDITIONS WILL CONTINUE SUNDAY NIGHT INTO
MONDAY WITH A FEW SHRA. A FEW SHSN MONDAY NIGHT...MAINLY ACROSS NE
OH/NW PA. CONDITIONS IMPROVING TO VFR FROM WEST TO EAST TUESDAY.
&&
.MARINE...
NO CHANGES TO THE HEADLINES ON THE LAKE TODAY. THE GALE STILL LOOKS
GOOD FOR LATE TODAY AND TONIGHT. STILL EXPECTING A SQUALL LINE TO
MOVE ACROSS THE LAKE THIS EVENING AND WIND GUSTS COULD APPROACH 50
KNOTS. WINDS WILL BECOME WESTERLY BEHIND THE COLD FRONT RESPONSIBLE
FOR THE SQUALL LINE. SPEEDS SHOULD GRADUALLY DIMINISH ON MONDAY AND
EXPECT A PROLONGED PERIOD OF SMALL CRAFT ADVISORIES ONCE THE GALE
COMES DOWN. LOCAL GUIDANCE ALSO SHOWS WATER LEVELS MAKING A RUN FOR
THE CRITICAL MARK LATE TONIGHT. WILL SEE HOW THINGS DEVELOP BUT
LATER SHIFTS MAY NEED TO GO WITH A LOW WATER ADVISORY. THE FLOW
WILL BECOME NW ON MONDAY AS HIGH PRESSURE BEGINS TO BUILD IN FROM
THE WEST. A SURFACE RIDGE WILL EVENTUALLY MOVE EAST OF THE LAKE
TUESDAY NIGHT ALLOWING THE FLOW TO BECOME SOUTHERLY. SOUTH TO
SOUTHWEST FLOW WILL THEN CONTINUE TILL A COLD FRONT CROSSES THE LAKE
AT THE VERY END OF THE PERIOD.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...WIND ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST MONDAY FOR
OHZ003-006>014-017>023-027>033-036>038-047-089.
PA...WIND ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST MONDAY FOR
PAZ001>003.
MARINE...GALE WARNING FROM 6 PM THIS EVENING TO 4 PM EST MONDAY FOR
LEZ061-142>149-162>169.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...LOMBARDY
SHORT TERM...LOMBARDY
LONG TERM...KUBINA
AVIATION...KUBINA
MARINE...KUBINA
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
909 AM EST SUN NOV 17 2013
.SYNOPSIS...
THE NEXT COLD FRONT IS EXPECTED TO PUSH THROUGH THE FORECAST
AREA SUNDAY NIGHT INTO EARLY MONDAY...FOLLOWED BY COLD CANADIAN HIGH
PRESSURE BUILDING OVER THE REGION THROUGH THE MIDDLE OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 9 AM...WESTWARD EXPANSION OF THE DENSE FOG APPEARS TO HAVE
BEEN HALTED BY THE WARMING BOUNDARY LAYER NOW THAT THE SUN IS
GETTING A BIT HIGHER IN THE SKY...AND SOME THIN SPOTS ARE BEGINNING
TO APPEAR OVER THE PIEDMONT. HOWEVER...THE DENSE FOG ADVISORY RAN
OUT AT 14Z AND CONDITIONS WILL IMPROVE ONLY SLOWLY...SO IT WAS
EXTENDED THROUGH 16Z. TEMPS ARE IN DECENT SHAPE. EXPECT FREQUENT
UPDATES THROUGH THIS AFTERNOON.
PREVIOUS DISCUSSION...
AS OF 545 AM EST SUNDAY...A DENSE FOG ADVISORY HAS BEEN ISSUED FOR
THE I-77 CORRIDOR. VSBYS HAVE BEEN STEADILY DECLINING AND A LARGE
AREA OF THE WRN PIEDMONT IS NOW DOWN TO A QUARTER MILE. THE ADVISORY
WAS RUN THROUGH 14 UTC. HOWEVER...THE LIGHT EASTERLY FLOW AND
INCREASING WARM ADVECTION ALOFT MAY HELP THE FOG TO HANG AROUND MOST
OF THE MORNING.
AS OF 240 AM EST SUNDAY...A STRONG SHORT WAVE TROUGH WILL SWEEP
ACROSS THE UPPER MID-WEST THIS EVENING. INCREASING SOUTHWESTERLY
FLOW AHEAD OF A POTENT UPPER TROUGH WILL RESULT IN INCREASING
CHANCES OF SHOWER ACTIVITY OVER THE FORECAST AREA. SHOWER CHANCES
WILL BE MAINLY CONFINED TO THE BLUE RIDGE THIS MORNING. BY THE
AFTERNOON THE GFS...SPC 4KM WRF AND THE RAP ALL BRING AN AREA OF
SHOWERS ACROSS THE UPSTATE AND NORTHEAST GEORGIA. THE PCPN IS BEING
FORCED BY STRONG LLVL WARM ADVECTION. THIS SEAMS REASONABLE AND POPS
RAMP UP QUICKLY EAST OF THE MOUNTAINS INTO THE AFTERNOON HOURS. CAPE
IS LIMITED AND THE ACTIVITY LOOKS AS THROUGH IT MAY BE SLIGHTLY
ELEVATED IN NATURE. SO WHILE THE THERE A CHANCE FOR A TSTM...IT
DOESN/T APPEAR THAT THERE IS ANY SEVERE RISK TODAY OR THIS EVENING.
LATER TONIGHT...HOWEVER...A STRONGLY FORCED LINE OF STORMS IS
EXPECTED TO SWEEP INTO THE NC MOUNTAINS. CONVECTIVE ALLOWING MODELS
GENERALLY HAVE THIS LINE ENTERING THE MOUNTAINS AROUND...OR A LITTLE
AFTER...06 UTC OR AROUND 1 AM. THERE IS DEEP UNIDIRECTIONAL FLOW
BEHIND THE LINE AND IT SHOULD BE MOVING QUITE FAST. EAST OF THE
MOUNTAINS THE NAM HAS A FAIR AMOUNT OF ELEVATED INSTABILITY...ON THE
ORDER OF 500-700 J/KG...THOUGH SURFACE BASED INSTABILITY IS QUITE
LOW. WHILE THE FORCING WILL BE STRONGER OVER WESTERN NC...THERE IS
HIGHER INSTABILITY SOUTH OF THE APPALACHIANS. THEREFORE THE LINE MAY
ACTUALLY HAVE A BETTER CHANCE OF PRODUCING SEVERE WEATHER AS IT
MOVES ACROSS NE GEORGIA AND THE WRN UPSTATE. I SUSPECT THE LINE WILL
WEAKEN CONSIDERABLY AFTER CROSSING THE MOUNTAINS...MUCH LIKE WHAT
THE 00 UTC HIGH RES WRF ARW IS INDICATING. HOWEVER...EVEN A
WEAKENING LINE WILL HAVE THE POTENTIAL TO TRANSLATE STRONG WINDS TO
THE SFC AS IT MOVES ACROSS THE FOOTHILLS AND PIEDMONT.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AT 210 AM EST SUNDAY...ON MONDAY MORNING A LOW AMPLITUDE UPPER
TROUGH WILL EXTEND FROM THE GREAT LAKES TO THE GULF STATES. AT THE
SAME TIME...A SURFACE COLD FRONT WILL EXTEND FROM CAPE COD...TO THE
NC OUTER BANKS...TO SOMEWHERE BETWEEN THE SC AND GA PIEDMONT...AND
THE SC AND GA COAST. THE FRONT WILL RAPIDLY MOVE AWAY FROM OUR
MONDAY MORNING...FOLLOWED BY A DRY...NW...WARMING DOWNSLOPE FLOW IN
A TIGHT PRESSURE GRADIENT...AND TEMPERATURES ALMOST 10 DEGREES ABOVE
NORMAL.
THE DEAMPLIFYING UPPER TROUGH WILL MOVE OFFSHORE ON MONDAY
NIGHT...FOLLOWED BY ZONAL FLOW ALOFT. SURFACE WINDS WILL BE SLOW TO
DIMINISH MONDAY NIGHT AS HIGH PRESSURE MOVES UP THE OH VALLEY...BUT
WINDS WILL VEER FROM NW TO N...DECREASING DOWNSLOPE FLOW WARMING. AS
A RESULT..MINIMUM TEMPERATURES MONDAY NIGHT WILL FALL TO NEAR
NORMAL. TUESDAY FEATURES DRY HIGH PRESSURE CENTERED OVER THE UPPER
OH RIVER VALLEY...AND A WEAK PRESSURE GRADIENT TO ITS SOUTH. COOL NE
FLOW WILL LIMIT MAXIMUM TEMPERATURES TO SEVERAL DEGREES BELOW NORMAL.
THE SURFACE HIGH WILL TAKE UP RESIDENCE ALONG THE EASTERN SEABOARD
TUESDAY NIGHT. BOTH THE NAM AND GFS SHOW SOME ADVANCE OF ATLANTIC
MOISTURE INLAND OVER COASTAL SC AND GA...WITH THE NAM MOISTURE
NEATLY REACHING THE UPPER SAVANNAH RIVER VALLEY. THE ECMWF SPREADS
IT MOISTURE FARTHER INLAND LIKE THE NAM...BUT IS FARTHER SOUTH.
UNLESS CLOUD COVER CAN MAKE INROADS OVER OUR AREA...MINIMUM
TEMPERATURES TUESDAY NIGHT WILL BE SEVERAL CATEGORIES BELOW NORMAL.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 145 AM EST SUNDAY...FOR THE PERIOD WEDNESDAY THROUGH SATURDAY.
HIGH PRESSURE IS SHOWN TO BE OVER NEW YORK STATE AT 12Z WEDNESDAY ON
BOTH THE GFS AND ECMWF. THIS WILL GIVE OUR REGION A COOL NE FLOW AS
HIGHS WILL BE ABOUT 10 DEGREES BELOW NORMAL. THE HIGH SHIFTS OFF THE
NEW ENGLAND COAST WITH THE LOW LEVEL WIND FLOW CHANGING FROM NE TO A
VERY LIGHT VARIABLE OR LIGHT EAST FLOW. WEDNESDAY AND WEDNESDAY
NIGHT ARE THE PERIODS IN THIS MEDIUM RANGE THAT HAS BEST MODEL
AGREEMENT. THE REST OF THE FORECAST PERIODS ARE BASED ON A
COMPROMISE FROM THE DAYS 5 TO 7 MODELS.
THE PREVIOUS CANADIAN MODEL HAD A LOW MOVING NE OUT OF THE NRN GULF
ON THURSDAY INTO FRIDAY BRINGING RAIN TO GA AND THE CAROLINAS AHEAD
OF THE FRONT. NONE OF THE OTHER MODELS HAD ANYTHING LIKE THIS. THE
NEWEST CANADIAN HAS BACKED OFF FROM THE LOW AHEAD OF THE FRONT AND
NOW HAS CONVECTION FORMING ALONG GULF COAST FROM TEXAS TO AL
THURSDAY NIGHT AND MOVING IT NORTH TO JOIN THE FRONT LATE FRIDAY
INTO SATURDAY.
THE GFS MAINTAINS SOME WEAK SURFACE RIDGING OVER THE CAROLINAS AND
DELAYS THE COLD FRONT ARRIVING UNTIL SATURDAY. THE GFS HAS SOME
ORGANIZED SHOWER ACTIVITY MOVING INTO THE NC MTNS LATE FRIDAY NIGHT
AND THEN ALL ACTIVITY BREAKS DOWN SATURDAY AS THE FRONT BECOMES MORE
DIFFUSE. IN FACT...THE GFS HAS ALL PRECIP SOUTH OF OUR AREA BY
SATURDAY EVENING WITH DRY AIR SPREADING IN AHEAD OF COLD HIGH
PRESSURE WHICH ORIGINATES FROM ALASKA AND NW CANADA.
THE CURRENT ECMWF HAS PRECIP MOVING INTO THE GREAT SMOKIES THURSDAY
EVENING THEN EXPANDING OVER THE REST OF THE WESTERN CAROLINAS AND NE
GA FRIDAY INTO SATURDAY. THIS RUN OF THE ECMWF MAINTAINS FRONTAL
CONVECTION AS IT CROSSES THE AREA SATURDAY NIGHT WITH AROUND A HALF
INCH QPF. DRY AIR ARRIVES ON SUNDAY ON THE ECMWF. THE NEWEST 00Z RUN
OF THE ECMWF JUST ARRIVED AND IT IS VERY MUCH CLOSER TO THE GFS.
NEWEST RUN HAS A WEAK FRONTAL BAND CROSSING MTNS 12Z SAT AND ACROSS
PIEDMONT 18Z SATURDAY...THEN DRY AIR ALL OVER BY 00Z SUNDAY.
TEMPERATURES WILL BE CLOSE TO OR JUST BELOW NORMALS FRIDAY AND
SATURDAY.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
AT KCLT...CLEAR SKIES EARLIER IN THE NIGHT SET THE STAGE FOR DENSE
FOG AT THE AIRFIELD. WITH WEAK WARM ADVECTION ALOFT...THIS IS THE
KIND OF FOG EVENT WHICH COULD LAST MOST OF THE MORNING. FOR NOW I
ONLY HAVE 1/4SM THROUGH 14 UTC AND 1/2SM TIL 15 UTC. THE DAY SHIFT
MAY NEED TO EXTEND THAT A FEW HOURS. CIGS SHOULD GRADUALLY LIFT INTO
THE AFTN BEFORE THEY FALL QUICKLY AGAIN THIS EVENING.
A LINE OF THUNDERSTORMS IS EXPECTED TO ENTER THE MOUNTAINS
TONIGHT...BUT AT THIS TIME IT DOESN/T APPEAR THE LINE WILL SURVIVE
IT/S TRIP ACROSS THE HIGH TERRAIN. STILL...A SIGNIFICANT WIND SHIFT
AND GUSTY WINDS SHOULD ACCOMPANY BNDRY ACROSS THE AIRFIELD. A WIND
SHIFT WAS NOT INCLUDED IN THIS ISSUANCE BUT BE AWARE THAT THE BNDRY
IS EXPECTED TO ARRIVE RIGHT AROUND 12 UTC...OR POSSIBLY AN HOUR OR 2
BEFORE.
ELSEWHERE...IFR OR LIFR CIGS HAVE DEVELOPED AT KHKY AND KAVL AND THE
CIGS WILL BE SLOW TO LIFT. IN FACT BOTH THE CIGS AND VSBYS MAY
BECOME WORSE OVER THE NEXT COUPLE HOURS. IFR CIGS WERE BEGINNING TO
DEVELOP OVER THE UPSTATE A LITTLE BEFORE 12 UTC. BASED ON MODEL
SOUNDINGS AND THE GENERAL SET UP THIS MORNING I EXPECT THAT IFR CIGS
WILL SOON COVER ALL THE UPSTATE WITH IFR CONDITIONS LASTING THROUGH
NOON. HOPEFULLY THERE WILL BE ENOUGH MIXING TO KEEP THE AREAS OF
DENSE FOG EAST OF THE UPSTATE AIRFIELDS THIS MORNING.
SCATTERED SHOWERS WILL BECOME MORE WIDESPREAD THIS AFTERNOON. A LINE
OF THUNDERSTORMS IS EXPECTED TO ENTER THE MOUNTAINS BETWEEN 06-09
UTC. WINDS SHOULD SHIFT AT KAVL AROUND OR A LITTLE BEFORE 09 UTC.
NOT SURE IF THE LINE WILL STILL BE PRODUCING LIGHTNING BY THE TIME
IT HITS KAVL...BUT THERE SHOULD BE GUSTY NW WINDS. THE LINE SHOULD
FURTHER WEAKEN AS IT MOVES OUT OF THE MTNS...BUT A SHARP WIND SHIFT
IS LIKELY TO AFFECT ALL OF THE TAF SITES BETWEEN 09-12 UTC.
OUTLOOK...A RETURN TO MUCH DRIER WEATHER IS EXPECTED BY LATE MONDAY.
CONDITIONS SHOULD BE MAINLY VFR FROM MONDAY NIGHT THROUGH THE MIDDLE
OF THE UPCOMING WEEK.
CONFIDENCE TABLE...
14-20Z 20-02Z 02-08Z 08-14Z
KCLT MED 63% HIGH 94% HIGH 87% HIGH 97%
KGSP HIGH 86% HIGH 87% HIGH 100% HIGH 87%
KAVL MED 75% HIGH 91% HIGH 87% HIGH 95%
KHKY HIGH 91% HIGH 87% HIGH 96% HIGH 82%
KGMU HIGH 86% MED 79% HIGH 100% HIGH 97%
KAND HIGH 83% HIGH 87% HIGH 93% HIGH 82%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.FIRE WEATHER...
A LINE OF THUNDERSTORMS IS EXPECTED TO MOVE ACROSS THE NORTH
CAROLINA MOUNTAINS EARLY MONDAY MORNING. WHILE THE LINE SHOULD
WEAKEN AS IT CROSSES THE MOUNTAINS...THE ACCOMPANYING OUTFLOW
BOUNDARY WOULD RESULT IN WINDS RAPIDLY SHIFTING TO THE WEST OR
NORTHWEST. OVER THE LINVILLE GORGE THIS IS MOST LIKELY TO HAPPEN
BETWEEN 1 AM AND 4 AM MONDAY. IN ADDITION TO SHIFTING WINDS...STRONG
WIND GUSTS ARE ALSO POSSIBLE WITH THE LINE.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...DENSE FOG ADVISORY UNTIL 11 AM EST THIS MORNING FOR NCZ033-
035>037-056-057-068>072-082-501>504.
SC...DENSE FOG ADVISORY UNTIL 11 AM EST THIS MORNING FOR SCZ009-014.
&&
$$
SYNOPSIS...DEO
NEAR TERM...MCAVOY/PM
SHORT TERM...JAT
LONG TERM...DEO
AVIATION...MCAVOY
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
816 AM EST SUN NOV 17 2013
.SYNOPSIS...
THE NEXT COLD FRONT IS EXPECTED TO PUSH THROUGH THE FORECAST
AREA SUNDAY NIGHT INTO EARLY MONDAY...FOLLOWED BY COLD CANADIAN HIGH
PRESSURE BUILDING OVER THE REGION THROUGH THE MIDDLE OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 8 AM...DENSE FOG CONTINUES TO OOZE ITS WAY WESTWARD TOWARD THE
BLUE RIDGE. HAVE ADDED ANOTHER STRIPE OF ZONES TO THE DENSE FOG
ADVISORY TO ACCOUNT FOR VISIBILITY DROPPING DOWN TO 1/4 MILE FROM
GASTONIA TO LINCOLNTON AND HICKORY. INCLUDED THE AREA AROUND THE
TABLE ROCK FIRE AS WELL. RADAR NOT DETECTING ANY PRECIP YET ACROSS
THE WESTERN CAROLINAS...SO THE PRECIP CHANCES WERE PUSHED BACK A FEW
HOURS TOWARD MIDDAY. TEMPS WERE ALSO ADJUSTED. EXPECT FREQUENT
UPDATES TODAY.
PREVIOUS DISCUSSION...
AS OF 545 AM EST SUNDAY...A DENSE FOG ADVISORY HAS BEEN ISSUED FOR
THE I-77 CORRIDOR. VSBYS HAVE BEEN STEADILY DECLINING AND A LARGE
AREA OF THE WRN PIEDMONT IS NOW DOWN TO A QUARTER MILE. THE ADVISORY
WAS RUN THROUGH 14 UTC. HOWEVER...THE LIGHT EASTERLY FLOW AND
INCREASING WARM ADVECTION ALOFT MAY HELP THE FOG TO HANG AROUND MOST
OF THE MORNING.
AS OF 240 AM EST SUNDAY...A STRONG SHORT WAVE TROUGH WILL SWEEP
ACROSS THE UPPER MID-WEST THIS EVENING. INCREASING SOUTHWESTERLY
FLOW AHEAD OF A POTENT UPPER TROUGH WILL RESULT IN INCREASING
CHANCES OF SHOWER ACTIVITY OVER THE FORECAST AREA. SHOWER CHANCES
WILL BE MAINLY CONFINED TO THE BLUE RIDGE THIS MORNING. BY THE
AFTERNOON THE GFS...SPC 4KM WRF AND THE RAP ALL BRING AN AREA OF
SHOWERS ACROSS THE UPSTATE AND NORTHEAST GEORGIA. THE PCPN IS BEING
FORCED BY STRONG LLVL WARM ADVECTION. THIS SEAMS REASONABLE AND POPS
RAMP UP QUICKLY EAST OF THE MOUNTAINS INTO THE AFTERNOON HOURS. CAPE
IS LIMITED AND THE ACTIVITY LOOKS AS THROUGH IT MAY BE SLIGHTLY
ELEVATED IN NATURE. SO WHILE THE THERE A CHANCE FOR A TSTM...IT
DOESN/T APPEAR THAT THERE IS ANY SEVERE RISK TODAY OR THIS EVENING.
LATER TONIGHT...HOWEVER...A STRONGLY FORCED LINE OF STORMS IS
EXPECTED TO SWEEP INTO THE NC MOUNTAINS. CONVECTIVE ALLOWING MODELS
GENERALLY HAVE THIS LINE ENTERING THE MOUNTAINS AROUND...OR A LITTLE
AFTER...06 UTC OR AROUND 1 AM. THERE IS DEEP UNIDIRECTIONAL FLOW
BEHIND THE LINE AND IT SHOULD BE MOVING QUITE FAST. EAST OF THE
MOUNTAINS THE NAM HAS A FAIR AMOUNT OF ELEVATED INSTABILITY...ON THE
ORDER OF 500-700 J/KG...THOUGH SURFACE BASED INSTABILITY IS QUITE
LOW. WHILE THE FORCING WILL BE STRONGER OVER WESTERN NC...THERE IS
HIGHER INSTABILITY SOUTH OF THE APPALACHIANS. THEREFORE THE LINE MAY
ACTUALLY HAVE A BETTER CHANCE OF PRODUCING SEVERE WEATHER AS IT
MOVES ACROSS NE GEORGIA AND THE WRN UPSTATE. I SUSPECT THE LINE WILL
WEAKEN CONSIDERABLY AFTER CROSSING THE MOUNTAINS...MUCH LIKE WHAT
THE 00 UTC HIGH RES WRF ARW IS INDICATING. HOWEVER...EVEN A
WEAKENING LINE WILL HAVE THE POTENTIAL TO TRANSLATE STRONG WINDS TO
THE SFC AS IT MOVES ACROSS THE FOOTHILLS AND PIEDMONT.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AT 210 AM EST SUNDAY...ON MONDAY MORNING A LOW AMPLITUDE UPPER
TROUGH WILL EXTEND FROM THE GREAT LAKES TO THE GULF STATES. AT THE
SAME TIME...A SURFACE COLD FRONT WILL EXTEND FROM CAPE COD...TO THE
NC OUTER BANKS...TO SOMEWHERE BETWEEN THE SC AND GA PIEDMONT...AND
THE SC AND GA COAST. THE FRONT WILL RAPIDLY MOVE AWAY FROM OUR
MONDAY MORNING...FOLLOWED BY A DRY...NW...WARMING DOWNSLOPE FLOW IN
A TIGHT PRESSURE GRADIENT...AND TEMPERATURES ALMOST 10 DEGREES ABOVE
NORMAL.
THE DEAMPLIFYING UPPER TROUGH WILL MOVE OFFSHORE ON MONDAY
NIGHT...FOLLOWED BY ZONAL FLOW ALOFT. SURFACE WINDS WILL BE SLOW TO
DIMINISH MONDAY NIGHT AS HIGH PRESSURE MOVES UP THE OH VALLEY...BUT
WINDS WILL VEER FROM NW TO N...DECREASING DOWNSLOPE FLOW WARMING. AS
A RESULT..MINIMUM TEMPERATURES MONDAY NIGHT WILL FALL TO NEAR
NORMAL. TUESDAY FEATURES DRY HIGH PRESSURE CENTERED OVER THE UPPER
OH RIVER VALLEY...AND A WEAK PRESSURE GRADIENT TO ITS SOUTH. COOL NE
FLOW WILL LIMIT MAXIMUM TEMPERATURES TO SEVERAL DEGREES BELOW NORMAL.
THE SURFACE HIGH WILL TAKE UP RESIDENCE ALONG THE EASTERN SEABOARD
TUESDAY NIGHT. BOTH THE NAM AND GFS SHOW SOME ADVANCE OF ATLANTIC
MOISTURE INLAND OVER COASTAL SC AND GA...WITH THE NAM MOISTURE
NEATLY REACHING THE UPPER SAVANNAH RIVER VALLEY. THE ECMWF SPREADS
IT MOISTURE FARTHER INLAND LIKE THE NAM...BUT IS FARTHER SOUTH.
UNLESS CLOUD COVER CAN MAKE INROADS OVER OUR AREA...MINIMUM
TEMPERATURES TUESDAY NIGHT WILL BE SEVERAL CATEGORIES BELOW NORMAL.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 145 AM EST SUNDAY...FOR THE PERIOD WEDNESDAY THROUGH SATURDAY.
HIGH PRESSURE IS SHOWN TO BE OVER NEW YORK STATE AT 12Z WEDNESDAY ON
BOTH THE GFS AND ECMWF. THIS WILL GIVE OUR REGION A COOL NE FLOW AS
HIGHS WILL BE ABOUT 10 DEGREES BELOW NORMAL. THE HIGH SHIFTS OFF THE
NEW ENGLAND COAST WITH THE LOW LEVEL WIND FLOW CHANGING FROM NE TO A
VERY LIGHT VARIABLE OR LIGHT EAST FLOW. WEDNESDAY AND WEDNESDAY
NIGHT ARE THE PERIODS IN THIS MEDIUM RANGE THAT HAS BEST MODEL
AGREEMENT. THE REST OF THE FORECAST PERIODS ARE BASED ON A
COMPROMISE FROM THE DAYS 5 TO 7 MODELS.
THE PREVIOUS CANADIAN MODEL HAD A LOW MOVING NE OUT OF THE NRN GULF
ON THURSDAY INTO FRIDAY BRINGING RAIN TO GA AND THE CAROLINAS AHEAD
OF THE FRONT. NONE OF THE OTHER MODELS HAD ANYTHING LIKE THIS. THE
NEWEST CANADIAN HAS BACKED OFF FROM THE LOW AHEAD OF THE FRONT AND
NOW HAS CONVECTION FORMING ALONG GULF COAST FROM TEXAS TO AL
THURSDAY NIGHT AND MOVING IT NORTH TO JOIN THE FRONT LATE FRIDAY
INTO SATURDAY.
THE GFS MAINTAINS SOME WEAK SURFACE RIDGING OVER THE CAROLINAS AND
DELAYS THE COLD FRONT ARRIVING UNTIL SATURDAY. THE GFS HAS SOME
ORGANIZED SHOWER ACTIVITY MOVING INTO THE NC MTNS LATE FRIDAY NIGHT
AND THEN ALL ACTIVITY BREAKS DOWN SATURDAY AS THE FRONT BECOMES MORE
DIFFUSE. IN FACT...THE GFS HAS ALL PRECIP SOUTH OF OUR AREA BY
SATURDAY EVENING WITH DRY AIR SPREADING IN AHEAD OF COLD HIGH
PRESSURE WHICH ORIGINATES FROM ALASKA AND NW CANADA.
THE CURRENT ECMWF HAS PRECIP MOVING INTO THE GREAT SMOKIES THURSDAY
EVENING THEN EXPANDING OVER THE REST OF THE WESTERN CAROLINAS AND NE
GA FRIDAY INTO SATURDAY. THIS RUN OF THE ECMWF MAINTAINS FRONTAL
CONVECTION AS IT CROSSES THE AREA SATURDAY NIGHT WITH AROUND A HALF
INCH QPF. DRY AIR ARRIVES ON SUNDAY ON THE ECMWF. THE NEWEST 00Z RUN
OF THE ECMWF JUST ARRIVED AND IT IS VERY MUCH CLOSER TO THE GFS.
NEWEST RUN HAS A WEAK FRONTAL BAND CROSSING MTNS 12Z SAT AND ACROSS
PIEDMONT 18Z SATURDAY...THEN DRY AIR ALL OVER BY 00Z SUNDAY.
TEMPERATURES WILL BE CLOSE TO OR JUST BELOW NORMALS FRIDAY AND
SATURDAY.
&&
.AVIATION /13Z SUNDAY THROUGH THURSDAY/...
AT KCLT...CLEAR SKIES EARLIER IN THE NIGHT SET THE STAGE FOR DENSE
FOG AT THE AIRFIELD. WITH WEAK WARM ADVECTION ALOFT...THIS IS THE
KIND OF FOG EVENT WHICH COULD LAST MOST OF THE MORNING. FOR NOW I
ONLY HAVE 1/4SM THROUGH 14 UTC AND 1/2SM TIL 15 UTC. THE DAY SHIFT
MAY NEED TO EXTEND THAT A FEW HOURS. CIGS SHOULD GRADUALLY LIFT INTO
THE AFTN BEFORE THEY FALL QUICKLY AGAIN THIS EVENING.
A LINE OF THUNDERSTORMS IS EXPECTED TO ENTER THE MOUNTAINS
TONIGHT...BUT AT THIS TIME IT DOESN/T APPEAR THE LINE WILL SURVIVE
IT/S TRIP ACROSS THE HIGH TERRAIN. STILL...A SIGNIFICANT WIND SHIFT
AND GUSTY WINDS SHOULD ACCOMPANY BNDRY ACROSS THE AIRFIELD. A WIND
SHIFT WAS NOT INCLUDED IN THIS ISSUANCE BUT BE AWARE THAT THE BNDRY
IS EXPECTED TO ARRIVE RIGHT AROUND 12 UTC...OR POSSIBLY AN HOUR OR 2
BEFORE.
ELSEWHERE...IFR OR LIFR CIGS HAVE DEVELOPED AT KHKY AND KAVL AND THE
CIGS WILL BE SLOW TO LIFT. IN FACT BOTH THE CIGS AND VSBYS MAY
BECOME WORSE OVER THE NEXT COUPLE HOURS. IFR CIGS WERE BEGINNING TO
DEVELOP OVER THE UPSTATE A LITTLE BEFORE 12 UTC. BASED ON MODEL
SOUNDINGS AND THE GENERAL SET UP THIS MORNING I EXPECT THAT IFR CIGS
WILL SOON COVER ALL THE UPSTATE WITH IFR CONDITIONS LASTING THROUGH
NOON. HOPEFULLY THERE WILL BE ENOUGH MIXING TO KEEP THE AREAS OF
DENSE FOG EAST OF THE UPSTATE AIRFIELDS THIS MORNING.
SCATTERED SHOWERS WILL BECOME MORE WIDESPREAD THIS AFTERNOON. A LINE
OF THUNDERSTORMS IS EXPECTED TO ENTER THE MOUNTAINS BETWEEN 06-09
UTC. WINDS SHOULD SHIFT AT KAVL AROUND OR A LITTLE BEFORE 09 UTC.
NOT SURE IF THE LINE WILL STILL BE PRODUCING LIGHTNING BY THE TIME
IT HITS KAVL...BUT THERE SHOULD BE GUSTY NW WINDS. THE LINE SHOULD
FURTHER WEAKEN AS IT MOVES OUT OF THE MTNS...BUT A SHARP WIND SHIFT
IS LIKELY TO AFFECT ALL OF THE TAF SITES BETWEEN 09-12 UTC.
OUTLOOK...A RETURN TO MUCH DRIER WEATHER IS EXPECTED BY LATE MONDAY.
CONDITIONS SHOULD BE MAINLY VFR FROM MONDAY NIGHT THROUGH THE MIDDLE
OF THE UPCOMING WEEK.
CONFIDENCE TABLE...
13-19Z 19-01Z 01-07Z 07-13Z
KCLT MED 68% HIGH 89% MED 76% HIGH 94%
KGSP HIGH 81% HIGH 91% HIGH 90% HIGH 87%
KAVL MED 64% HIGH 91% HIGH 85% HIGH 88%
KHKY HIGH 91% HIGH 91% HIGH 85% HIGH 82%
KGMU HIGH 81% HIGH 83% HIGH 93% HIGH 96%
KAND MED 77% HIGH 91% HIGH 85% HIGH 83%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.FIRE WEATHER...
A LINE OF THUNDERSTORMS IS EXPECTED TO MOVE ACROSS THE NORTH
CAROLINA MOUNTAINS EARLY MONDAY MORNING. WHILE THE LINE SHOULD
WEAKEN AS IT CROSSES THE MOUNTAINS...THE ACCOMPANYING OUTFLOW
BOUNDARY WOULD RESULT IN WINDS RAPIDLY SHIFTING TO THE WEST OR
NORTHWEST. OVER THE LINVILLE GORGE THIS IS MOST LIKELY TO HAPPEN
BETWEEN 1 AM AND 4 AM MONDAY. IN ADDITION TO SHIFTING WINDS...STRONG
WIND GUSTS ARE ALSO POSSIBLE WITH THE LINE.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR NCZ033-
035>037-056-057-068>072-082-501>504.
SC...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR SCZ009-014.
&&
$$
SYNOPSIS...DEO
NEAR TERM...MCAVOY/PM
SHORT TERM...JAT
LONG TERM...DEO
AVIATION...MCAVOY
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
646 AM EST SUN NOV 17 2013
.SYNOPSIS...
THE NEXT COLD FRONT IS EXPECTED TO PUSH THROUGH THE FORECAST
AREA SUNDAY NIGHT INTO EARLY MONDAY...FOLLOWED BY COLD CANADIAN HIGH
PRESSURE BUILDING OVER THE REGION THROUGH THE MIDDLE OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 545 AM EST SUNDAY...A DENSE FOG ADVISORY HAS BEEN ISSUED FOR
THE I-77 CORRIDOR. VSBYS HAVE BEEN STEADILY DECLINING AND A LARGE
AREA OF THE WRN PIEDMONT IS NOW DOWN TO A QUARTER MILE. THE ADVISORY
WAS RUN THROUGH 14 UTC. HOWEVER...THE LIGHT EASTERLY FLOW AND
INCREASING WARM ADVECTION ALOFT MAY HELP THE FOG TO HANG AROUND MOST
OF THE MORNING.
AS OF 240 AM EST SUNDAY...A STRONG SHORT WAVE TROUGH WILL SWEEP
ACROSS THE UPPER MID-WEST THIS EVENING. INCREASING SOUTHWESTERLY
FLOW AHEAD OF A POTENT UPPER TROUGH WILL RESULT IN INCREASING
CHANCES OF SHOWER ACTIVITY OVER THE FORECAST AREA. SHOWER CHANCES
WILL BE MAINLY CONFINED TO THE BLUE RIDGE THIS MORNING. BY THE
AFTERNOON THE GFS...SPC 4KM WRF AND THE RAP ALL BRING AN AREA OF
SHOWERS ACROSS THE UPSTATE AND NORTHEAST GEORGIA. THE PCPN IS BEING
FORCED BY STRONG LLVL WARM ADVECTION. THIS SEAMS REASONABLE AND POPS
RAMP UP QUICKLY EAST OF THE MOUNTAINS INTO THE AFTERNOON HOURS. CAPE
IS LIMITED AND THE ACTIVITY LOOKS AS THROUGH IT MAY BE SLIGHTLY
ELEVATED IN NATURE. SO WHILE THE THERE A CHANCE FOR A TSTM...IT
DOESN/T APPEAR THAT THERE IS ANY SEVERE RISK TODAY OR THIS EVENING.
LATER TONIGHT...HOWEVER...A STRONGLY FORCED LINE OF STORMS IS
EXPECTED TO SWEEP INTO THE NC MOUNTAINS. CONVECTIVE ALLOWING MODELS
GENERALLY HAVE THIS LINE ENTERING THE MOUNTAINS AROUND...OR A LITTLE
AFTER...06 UTC OR AROUND 1 AM. THERE IS DEEP UNIDIRECTIONAL FLOW
BEHIND THE LINE AND IT SHOULD BE MOVING QUITE FAST. EAST OF THE
MOUNTAINS THE NAM HAS A FAIR AMOUNT OF ELEVATED INSTABILITY...ON THE
ORDER OF 500-700 J/KG...THOUGH SURFACE BASED INSTABILITY IS QUITE
LOW. WHILE THE FORCING WILL BE STRONGER OVER WESTERN NC...THERE IS
HIGHER INSTABILITY SOUTH OF THE APPALACHIANS. THEREFORE THE LINE MAY
ACTUALLY HAVE A BETTER CHANCE OF PRODUCING SEVERE WEATHER AS IT
MOVES ACROSS NE GEORGIA AND THE WRN UPSTATE. I SUSPECT THE LINE WILL
WEAKEN CONSIDERABLY AFTER CROSSING THE MOUNTAINS...MUCH LIKE WHAT
THE 00 UTC HIGH RES WRF ARW IS INDICATING. HOWEVER...EVEN A
WEAKENING LINE WILL HAVE THE POTENTIAL TO TRANSLATE STRONG WINDS TO
THE SFC AS IT MOVES ACROSS THE FOOTHILLS AND PIEDMONT.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AT 210 AM EST SUNDAY...ON MONDAY MORNING A LOW AMPLITUDE UPPER
TROUGH WILL EXTEND FROM THE GREAT LAKES TO THE GULF STATES. AT THE
SAME TIME...A SURFACE COLD FRONT WILL EXTEND FROM CAPE COD...TO THE
NC OUTER BANKS...TO SOMEWHERE BETWEEN THE SC AND GA PIEDMONT...AND
THE SC AND GA COAST. THE FRONT WILL RAPIDLY MOVE AWAY FROM OUR
MONDAY MORNING...FOLLOWED BY A DRY...NW...WARMING DOWNSLOPE FLOW IN
A TIGHT PRESSURE GRADIENT...AND TEMPERATURES ALMOST 10 DEGREES ABOVE
NORMAL.
THE DEAMPLIFYING UPPER TROUGH WILL MOVE OFFSHORE ON MONDAY
NIGHT...FOLLOWED BY ZONAL FLOW ALOFT. SURFACE WINDS WILL BE SLOW TO
DIMINISH MONDAY NIGHT AS HIGH PRESSURE MOVES UP THE OH VALLEY...BUT
WINDS WILL VEER FROM NW TO N...DECREASING DOWNSLOPE FLOW WARMING. AS
A RESULT..MINIMUM TEMPERATURES MONDAY NIGHT WILL FALL TO NEAR
NORMAL. TUESDAY FEATURES DRY HIGH PRESSURE CENTERED OVER THE UPPER
OH RIVER VALLEY...AND A WEAK PRESSURE GRADIENT TO ITS SOUTH. COOL NE
FLOW WILL LIMIT MAXIMUM TEMPERATURES TO SEVERAL DEGREES BELOW NORMAL.
THE SURFACE HIGH WILL TAKE UP RESIDENCE ALONG THE EASTERN SEABOARD
TUESDAY NIGHT. BOTH THE NAM AND GFS SHOW SOME ADVANCE OF ATLANTIC
MOISTURE INLAND OVER COASTAL SC AND GA...WITH THE NAM MOISTURE
NEATLY REACHING THE UPPER SAVANNAH RIVER VALLEY. THE ECMWF SPREADS
IT MOISTURE FARTHER INLAND LIKE THE NAM...BUT IS FARTHER SOUTH.
UNLESS CLOUD COVER CAN MAKE INROADS OVER OUR AREA...MINIMUM
TEMPERATURES TUESDAY NIGHT WILL BE SEVERAL CATEGORIES BELOW NORMAL.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 145 AM EST SUNDAY...FOR THE PERIOD WEDNESDAY THROUGH SATURDAY.
HIGH PRESSURE IS SHOWN TO BE OVER NEW YORK STATE AT 12Z WEDNESDAY ON
BOTH THE GFS AND ECMWF. THIS WILL GIVE OUR REGION A COOL NE FLOW AS
HIGHS WILL BE ABOUT 10 DEGREES BELOW NORMAL. THE HIGH SHIFTS OFF THE
NEW ENGLAND COAST WITH THE LOW LEVEL WIND FLOW CHANGING FROM NE TO A
VERY LIGHT VARIABLE OR LIGHT EAST FLOW. WEDNESDAY AND WEDNESDAY
NIGHT ARE THE PERIODS IN THIS MEDIUM RANGE THAT HAS BEST MODEL
AGREEMENT. THE REST OF THE FORECAST PERIODS ARE BASED ON A
COMPROMISE FROM THE DAYS 5 TO 7 MODELS.
THE PREVIOUS CANADIAN MODEL HAD A LOW MOVING NE OUT OF THE NRN GULF
ON THURSDAY INTO FRIDAY BRINGING RAIN TO GA AND THE CAROLINAS AHEAD
OF THE FRONT. NONE OF THE OTHER MODELS HAD ANYTHING LIKE THIS. THE
NEWEST CANADIAN HAS BACKED OFF FROM THE LOW AHEAD OF THE FRONT AND
NOW HAS CONVECTION FORMING ALONG GULF COAST FROM TEXAS TO AL
THURSDAY NIGHT AND MOVING IT NORTH TO JOIN THE FRONT LATE FRIDAY
INTO SATURDAY.
THE GFS MAINTAINS SOME WEAK SURFACE RIDGING OVER THE CAROLINAS AND
DELAYS THE COLD FRONT ARRIVING UNTIL SATURDAY. THE GFS HAS SOME
ORGANIZED SHOWER ACTIVITY MOVING INTO THE NC MTNS LATE FRIDAY NIGHT
AND THEN ALL ACTIVITY BREAKS DOWN SATURDAY AS THE FRONT BECOMES MORE
DIFFUSE. IN FACT...THE GFS HAS ALL PRECIP SOUTH OF OUR AREA BY
SATURDAY EVENING WITH DRY AIR SPREADING IN AHEAD OF COLD HIGH
PRESSURE WHICH ORIGINATES FROM ALASKA AND NW CANADA.
THE CURRENT ECMWF HAS PRECIP MOVING INTO THE GREAT SMOKIES THURSDAY
EVENING THEN EXPANDING OVER THE REST OF THE WESTERN CAROLINAS AND NE
GA FRIDAY INTO SATURDAY. THIS RUN OF THE ECMWF MAINTAINS FRONTAL
CONVECTION AS IT CROSSES THE AREA SATURDAY NIGHT WITH AROUND A HALF
INCH QPF. DRY AIR ARRIVES ON SUNDAY ON THE ECMWF. THE NEWEST 00Z RUN
OF THE ECMWF JUST ARRIVED AND IT IS VERY MUCH CLOSER TO THE GFS.
NEWEST RUN HAS A WEAK FRONTAL BAND CROSSING MTNS 12Z SAT AND ACROSS
PIEDMONT 18Z SATURDAY...THEN DRY AIR ALL OVER BY 00Z SUNDAY.
TEMPERATURES WILL BE CLOSE TO OR JUST BELOW NORMALS FRIDAY AND
SATURDAY.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AT KCLT...CLEAR SKIES EARLIER IN THE NIGHT SET THE STAGE FOR DENSE
FOG AT THE AIRFIELD. WITH WEAK WARM ADVECTION ALOFT...THIS IS THE
KIND OF FOG EVENT WHICH COULD LAST MOST OF THE MORNING. FOR NOW I
ONLY HAVE 1/4SM THROUGH 14 UTC AND 1/2SM TIL 15 UTC. THE DAY SHIFT
MAY NEED TO EXTEND THAT A FEW HOURS. CIGS SHOULD GRADUALLY LIFT INTO
THE AFTN BEFORE THEY FALL QUICKLY AGAIN THIS EVENING.
A LINE OF THUNDERSTORMS IS EXPECTED TO ENTER THE MOUNTAINS
TONIGHT...BUT AT THIS TIME IT DOESN/T APPEAR THE LINE WILL SURVIVE
IT/S TRIP ACROSS THE HIGH TERRAIN. STILL...A SIGNIFICANT WIND SHIFT
AND GUSTY WINDS SHOULD ACCOMPANY BNDRY ACROSS THE AIRFIELD. A WIND
SHIFT WAS NOT INCLUDED IN THIS ISSUANCE BUT BE AWARE THAT THE BNDRY
IS EXPECTED TO ARRIVE RIGHT AROUND 12 UTC...OR POSSIBLY AN HOUR OR 2
BEFORE.
ELSEWHERE...IFR OR LIFR CIGS HAVE DEVELOPED AT KHKY AND KAVL AND THE
CIGS WILL BE SLOW TO LIFT. IN FACT BOTH THE CIGS AND VSBYS MAY
BECOME WORSE OVER THE NEXT COUPLE HOURS. IFR CIGS WERE BEGINNING TO
DEVELOP OVER THE UPSTATE A LITTLE BEFORE 12 UTC. BASED ON MODEL
SOUNDINGS AND THE GENERAL SET UP THIS MORNING I EXPECT THAT IFR CIGS
WILL SOON COVER ALL THE UPSTATE WITH IFR CONDITIONS LASTING THROUGH
NOON. HOPEFULLY THERE WILL BE ENOUGH MIXING TO KEEP THE AREAS OF
DENSE FOG EAST OF THE UPSTATE AIRFIELDS THIS MORNING.
SCATTERED SHOWERS WILL BECOME MORE WIDESPREAD THIS AFTERNOON. A LINE
OF THUNDERSTORMS IS EXPECTED TO ENTER THE MOUNTAINS BETWEEN 06-09
UTC. WINDS SHOULD SHIFT AT KAVL AROUND OR A LITTLE BEFORE 09 UTC.
NOT SURE IF THE LINE WILL STILL BE PRODUCING LIGHTNING BY THE TIME
IT HITS KAVL...BUT THERE SHOULD BE GUSTY NW WINDS. THE LINE SHOULD
FURTHER WEAKEN AS IT MOVES OUT OF THE MTNS...BUT A SHARP WIND SHIFT
IS LIKELY TO AFFECT ALL OF THE TAF SITES BETWEEN 09-12 UTC.
OUTLOOK...A RETURN TO MUCH DRIER WEATHER IS EXPECTED BY LATE MONDAY.
CONDITIONS SHOULD BE MAINLY VFR FROM MONDAY NIGHT THROUGH THE MIDDLE
OF THE UPCOMING WEEK.
CONFIDENCE TABLE...
11-17Z 17-23Z 23-05Z 05-11Z
KCLT LOW 54% HIGH 87% MED 74% HIGH 82%
KGSP HIGH 80% HIGH 93% HIGH 81% HIGH 93%
KAVL LOW 57% HIGH 96% HIGH 84% HIGH 80%
KHKY HIGH 88% HIGH 100% MED 78% HIGH 84%
KGMU MED 78% HIGH 87% HIGH 81% HIGH 97%
KAND MED 66% HIGH 96% MED 74% HIGH 88%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.FIRE WEATHER...
A LINE OF THUNDERSTORMS IS EXPECTED TO MOVE ACROSS THE NORTH
CAROLINA MOUNTAINS EARLY MONDAY MORNING. WHILE THE LINE SHOULD
WEAKEN AS IT CROSSES THE MOUNTAINS...THE ACCOMPANYING OUTFLOW
BOUNDARY WOULD RESULT IN WINDS RAPIDLY SHIFTING TO THE WEST OR
NORTHWEST. OVER THE LINVILLE GORGE THIS IS MOST LIKELY TO HAPPEN
BETWEEN 1 AM AND 4 AM MONDAY. IN ADDITION TO SHIFTING WINDS...STRONG
WIND GUSTS ARE ALSO POSSIBLE WITH THE LINE.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR NCZ036-037-
057-071-072-082.
SC...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR SCZ009-014.
&&
$$
SYNOPSIS...DEO
NEAR TERM...MCAVOY
SHORT TERM...JAT
LONG TERM...DEO
AVIATION...MCAVOY
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
631 AM EST SUN NOV 17 2013
.SYNOPSIS...
THE NEXT COLD FRONT IS EXPECTED TO PUSH THROUGH THE FORECAST
AREA SUNDAY NIGHT INTO EARLY MONDAY...FOLLOWED BY COLD CANADIAN HIGH
PRESSURE BUILDING OVER THE REGION THROUGH THE MIDDLE OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 545 AM EST SUNDAY...A DENSE FOG ADVISORY HAS BEEN ISSUED FOR
THE I-77 CORRIDOR. VSBYS HAVE BEEN STEADILY DECLINING AND A LARGE
AREA OF THE WRN PIEDMONT IS NOW DOWN TO A QUARTER MILE. THE ADVISORY
WAS RUN THROUGH 14 UTC. HOWEVER...THE LIGHT EASTERLY FLOW AND
INCREASING WARM ADVECTION ALOFT MAY HELP THE FOG TO HANG AROUND MOST
OF THE MORNING.
AS OF 240 AM EST SUNDAY...A STRONG SHORT WAVE TROUGH WILL SWEEP
ACROSS THE UPPER MID-WEST THIS EVENING. INCREASING SOUTHWESTERLY
FLOW AHEAD OF A POTENT UPPER TROUGH WILL RESULT IN INCREASING
CHANCES OF SHOWER ACTIVITY OVER THE FORECAST AREA. SHOWER CHANCES
WILL BE MAINLY CONFINED TO THE BLUE RIDGE THIS MORNING. BY THE
AFTERNOON THE GFS...SPC 4KM WRF AND THE RAP ALL BRING AN AREA OF
SHOWERS ACROSS THE UPSTATE AND NORTHEAST GEORGIA. THE PCPN IS BEING
FORCED BY STRONG LLVL WARM ADVECTION. THIS SEAMS REASONABLE AND POPS
RAMP UP QUICKLY EAST OF THE MOUNTAINS INTO THE AFTERNOON HOURS. CAPE
IS LIMITED AND THE ACTIVITY LOOKS AS THROUGH IT MAY BE SLIGHTLY
ELEVATED IN NATURE. SO WHILE THE THERE A CHANCE FOR A TSTM...IT
DOESN/T APPEAR THAT THERE IS ANY SEVERE RISK TODAY OR THIS EVENING.
LATER TONIGHT...HOWEVER...A STRONGLY FORCED LINE OF STORMS IS
EXPECTED TO SWEEP INTO THE NC MOUNTAINS. CONVECTIVE ALLOWING MODELS
GENERALLY HAVE THIS LINE ENTERING THE MOUNTAINS AROUND...OR A LITTLE
AFTER...06 UTC OR AROUND 1 AM. THERE IS DEEP UNIDIRECTIONAL FLOW
BEHIND THE LINE AND IT SHOULD BE MOVING QUITE FAST. EAST OF THE
MOUNTAINS THE NAM HAS A FAIR AMOUNT OF ELEVATED INSTABILITY...ON THE
ORDER OF 500-700 J/KG...THOUGH SURFACE BASED INSTABILITY IS QUITE
LOW. WHILE THE FORCING WILL BE STRONGER OVER WESTERN NC...THERE IS
HIGHER INSTABILITY SOUTH OF THE APPALACHIANS. THEREFORE THE LINE MAY
ACTUALLY HAVE A BETTER CHANCE OF PRODUCING SEVERE WEATHER AS IT
MOVES ACROSS NE GEORGIA AND THE WRN UPSTATE. I SUSPECT THE LINE WILL
WEAKEN CONSIDERABLY AFTER CROSSING THE MOUNTAINS...MUCH LIKE WHAT
THE 00 UTC HIGH RES WRF ARW IS INDICATING. HOWEVER...EVEN A
WEAKENING LINE WILL HAVE THE POTENTIAL TO TRANSLATE STRONG WINDS TO
THE SFC AS IT MOVES ACROSS THE FOOTHILLS AND PIEDMONT.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AT 210 AM EST SUNDAY...ON MONDAY MORNING A LOW AMPLITUDE UPPER
TROUGH WILL EXTEND FROM THE GREAT LAKES TO THE GULF STATES. AT THE
SAME TIME...A SURFACE COLD FRONT WILL EXTEND FROM CAPE COD...TO THE
NC OUTER BANKS...TO SOMEWHERE BETWEEN THE SC AND GA PIEDMONT...AND
THE SC AND GA COAST. THE FRONT WILL RAPIDLY MOVE AWAY FROM OUR
MONDAY MORNING...FOLLOWED BY A DRY...NW...WARMING DOWNSLOPE FLOW IN
A TIGHT PRESSURE GRADIENT...AND TEMPERATURES ALMOST 10 DEGREES ABOVE
NORMAL.
THE DEAMPLIFYING UPPER TROUGH WILL MOVE OFFSHORE ON MONDAY
NIGHT...FOLLOWED BY ZONAL FLOW ALOFT. SURFACE WINDS WILL BE SLOW TO
DIMINISH MONDAY NIGHT AS HIGH PRESSURE MOVES UP THE OH VALLEY...BUT
WINDS WILL VEER FROM NW TO N...DECREASING DOWNSLOPE FLOW WARMING. AS
A RESULT..MINIMUM TEMPERATURES MONDAY NIGHT WILL FALL TO NEAR
NORMAL. TUESDAY FEATURES DRY HIGH PRESSURE CENTERED OVER THE UPPER
OH RIVER VALLEY...AND A WEAK PRESSURE GRADIENT TO ITS SOUTH. COOL NE
FLOW WILL LIMIT MAXIMUM TEMPERATURES TO SEVERAL DEGREES BELOW NORMAL.
THE SURFACE HIGH WILL TAKE UP RESIDENCE ALONG THE EASTERN SEABOARD
TUESDAY NIGHT. BOTH THE NAM AND GFS SHOW SOME ADVANCE OF ATLANTIC
MOISTURE INLAND OVER COASTAL SC AND GA...WITH THE NAM MOISTURE
NEATLY REACHING THE UPPER SAVANNAH RIVER VALLEY. THE ECMWF SPREADS
IT MOISTURE FARTHER INLAND LIKE THE NAM...BUT IS FARTHER SOUTH.
UNLESS CLOUD COVER CAN MAKE INROADS OVER OUR AREA...MINIMUM
TEMPERATURES TUESDAY NIGHT WILL BE SEVERAL CATEGORIES BELOW NORMAL.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 145 AM EST SUNDAY...FOR THE PERIOD WEDNESDAY THROUGH SATURDAY.
HIGH PRESSURE IS SHOWN TO BE OVER NEW YORK STATE AT 12Z WEDNESDAY ON
BOTH THE GFS AND ECMWF. THIS WILL GIVE OUR REGION A COOL NE FLOW AS
HIGHS WILL BE ABOUT 10 DEGREES BELOW NORMAL. THE HIGH SHIFTS OFF THE
NEW ENGLAND COAST WITH THE LOW LEVEL WIND FLOW CHANGING FROM NE TO A
VERY LIGHT VARIABLE OR LIGHT EAST FLOW. WEDNESDAY AND WEDNESDAY
NIGHT ARE THE PERIODS IN THIS MEDIUM RANGE THAT HAS BEST MODEL
AGREEMENT. THE REST OF THE FORECAST PERIODS ARE BASED ON A
COMPROMISE FROM THE DAYS 5 TO 7 MODELS.
THE PREVIOUS CANADIAN MODEL HAD A LOW MOVING NE OUT OF THE NRN GULF
ON THURSDAY INTO FRIDAY BRINGING RAIN TO GA AND THE CAROLINAS AHEAD
OF THE FRONT. NONE OF THE OTHER MODELS HAD ANYTHING LIKE THIS. THE
NEWEST CANADIAN HAS BACKED OFF FROM THE LOW AHEAD OF THE FRONT AND
NOW HAS CONVECTION FORMING ALONG GULF COAST FROM TEXAS TO AL
THURSDAY NIGHT AND MOVING IT NORTH TO JOIN THE FRONT LATE FRIDAY
INTO SATURDAY.
THE GFS MAINTAINS SOME WEAK SURFACE RIDGING OVER THE CAROLINAS AND
DELAYS THE COLD FRONT ARRIVING UNTIL SATURDAY. THE GFS HAS SOME
ORGANIZED SHOWER ACTIVITY MOVING INTO THE NC MTNS LATE FRIDAY NIGHT
AND THEN ALL ACTIVITY BREAKS DOWN SATURDAY AS THE FRONT BECOMES MORE
DIFFUSE. IN FACT...THE GFS HAS ALL PRECIP SOUTH OF OUR AREA BY
SATURDAY EVENING WITH DRY AIR SPREADING IN AHEAD OF COLD HIGH
PRESSURE WHICH ORIGINATES FROM ALASKA AND NW CANADA.
THE CURRENT ECMWF HAS PRECIP MOVING INTO THE GREAT SMOKIES THURSDAY
EVENING THEN EXPANDING OVER THE REST OF THE WESTERN CAROLINAS AND NE
GA FRIDAY INTO SATURDAY. THIS RUN OF THE ECMWF MAINTAINS FRONTAL
CONVECTION AS IT CROSSES THE AREA SATURDAY NIGHT WITH AROUND A HALF
INCH QPF. DRY AIR ARRIVES ON SUNDAY ON THE ECMWF. THE NEWEST 00Z RUN
OF THE ECMWF JUST ARRIVED AND IT IS VERY MUCH CLOSER TO THE GFS.
NEWEST RUN HAS A WEAK FRONTAL BAND CROSSING MTNS 12Z SAT AND ACROSS
PIEDMONT 18Z SATURDAY...THEN DRY AIR ALL OVER BY 00Z SUNDAY.
TEMPERATURES WILL BE CLOSE TO OR JUST BELOW NORMALS FRIDAY AND
SATURDAY.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AT KCLT...SKIES HAVE CLEARED TEMPORARILY AT THE AIRFIELD. JUST A FEW
MILES TO THE WEST THERE IS AN BORDERLINE MVFR/VFR DECK. JUST A FEW
MILES TO THE EAST THERE IS AN EXPANDING AREA OF FOG AND IFR/LIFR
STRATUS AND FOG. BASED ON THE H8 DRYING SEEN ON THE LATEST NAM AND
RUC...WENT WITH TEMPO IFR VSBYS AND LIFR CIGS. ONCE A HIGHER DECK
FINALLY SPREADS BACK IN HOPEFULLY THE LOWER STUFF WILL LIFT FOR A
WHILE. THAT SAID...IFR CIGS ARE EXPECTED TO DEVELOP AGAIN TOWARD 12
UTC AND LAST THROUGH THE MORNING. WINDS WILL BE LIGHT AND VARIABLE
THROUGH THE MORNING HOURS.
A LINE OF THUNDERSTORMS IS EXPECTED TO ENTER THE MOUNTAINS
TONIGHT...BUT AT THIS TIME IT DOESN/T APPEAR THE LINE WILL SURVIVE
IT/S TRIP ACROSS THE HIGH TERRAIN. STILL...A SIGNIFICANT WIND SHIFT
AND GUSTY WINDS MAY ACCOMPANY THE OUTFLOW BNDRY TOWARD MONDAY
MORNING. THIS IS A LITTLE OUTSIDE THE VALID PERIOD OF THE TAF...BUT
IT/S SOMETHING TO WATCH CLOSELY.
ELSEWHERE...VFR CIGS ARE CURRENTLY OVER ALL THE REMAINING TAF SITES.
STRENGTHENING UPSLOPE FLOW WILL HELP THESE CIGS TO GRADUALLY LOWER
DURING THE NIGHT. EXPECT THAT AN MVFR CIG WILL DEVELOP FIRST AROUND
2500 FEET WITH IFR STRATUS DEVELOPING TOWARD MORNING. THE LOW CIGS
ARE THEN EXPECTED TO LAST A LITTLE PAST NOON. SHOWERS WILL BECOME
MORE WIDESPREAD THIS EVENING. A LINE OF THUNDERSTORMS IS EXPECTED TO
ENTER THE MOUNTAINS BETWEEN 06-09 UTC. THE LINE MAY AFFECT KAVL.
EVEN IF THE STORMS WEAKEN...A SHARP WIND SHIFT IS LIKELY TO AFFECT
ALL OF THE TAF SITES A LITTLE BEYOND THE VALID PERIOD OF THE CURRENT
SET OF TAFS.
OUTLOOK...A RETURN TO MUCH DRIER WEATHER IS EXPECTED BY LATE MONDAY.
CONDITIONS SHOULD BE MAINLY VFR FROM MONDAY NIGHT THROUGH THE MIDDLE
OF THE UPCOMING WEEK.
CONFIDENCE TABLE...
11-17Z 17-23Z 23-05Z 05-11Z
KCLT LOW 54% HIGH 87% MED 74% HIGH 82%
KGSP HIGH 80% HIGH 93% HIGH 81% HIGH 93%
KAVL LOW 57% HIGH 96% HIGH 84% HIGH 80%
KHKY HIGH 88% HIGH 100% MED 78% HIGH 84%
KGMU MED 78% HIGH 87% HIGH 81% HIGH 97%
KAND MED 66% HIGH 96% MED 74% HIGH 88%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.FIRE WEATHER...
A LINE OF THUNDERSTORMS IS EXPECTED TO MOVE ACROSS THE NORTH
CAROLINA MOUNTAINS EARLY MONDAY MORNING. WHILE THE LINE SHOULD
WEAKEN AS IT CROSSES THE MOUNTAINS...THE ACCOMPANYING OUTFLOW
BOUNDARY WOULD RESULT IN WINDS RAPIDLY SHIFTING TO THE WEST OR
NORTHWEST. OVER THE LINVILLE GORGE THIS IS MOST LIKELY TO HAPPEN
BETWEEN 1 AM AND 4 AM MONDAY. IN ADDITION TO SHIFTING WINDS...STRONG
WIND GUSTS ARE ALSO POSSIBLE WITH THE LINE.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR NCZ036-037-
057-071-072-082.
SC...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR SCZ009-014.
&&
$$
SYNOPSIS...DEO
NEAR TERM...MCAVOY
SHORT TERM...JAT
LONG TERM...DEO
AVIATION...MCAVOY
FIRE WEATHER...MCAVOY
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
554 AM CST SUN NOV 17 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 412 AM CST SUN NOV 17 2013
ON THE BIG PICTURE EARLY THIS MORNING...DEEP TROUGH THROUGH THE
PLAINS STATES WITH STRONG JET ENERGY JET GETTING READY TO BOTTOM OUT
AND SWING NORTHEAST THROUGH THE OHIO VALLEY TODAY. MAIN SURFACE LOW
PRESSURE STARTING TO WIND UP ACROSS NORTHEAST KANSAS...WITH
REFLECTION OF UPPER TROUGH EXTENDING BACK INTO SOUTHWEST SOUTH
DAKOTA. LEADING WAVE LIFTING/WEAKENING THROUGH NORTHERN MINNESOTA...
WITH BACKWASH OF STRATUS ACROSS NORTHERN MINNESOTA/EASTERN NORTH
DAKOTA...EXTENDING INTO EAST CENTRAL SOUTH DAKOTA. SMALLER POCKET OF
STRATUS/FOG SLIPPING SOUTHWARD TOWARD KFSD AREA ALONG I29...WITH
EVEN A FEW 1/4 TO 1/2SM VISIBILITIES NOTED ALONG LEADING EDGE.
MANY SUBTLE ELEMENTS TO FORECAST OVER THE NEXT 12 TO 24 HOURS...
BUT FOR THE MOST PART WILL BE SPARED BY ANYTHING TOO SIGNIFICANT AS
UPPER TROUGH SLIPS THROUGH THE REGION EARLY TODAY.
MAIN UPPER ENERGY FOCUSED WELL SOUTH OF THE AREA TODAY...HOWEVER...
WILL HAVE PERIOD OF DECENT DIV Q AND PV ADVECTION FOR MAINLY
SOUTHEASTERN CWA THROUGH THE MID TO LATE MORNING HOURS. AREA OF
LIGHT RAINFALL WILL MOVE OUT OF NEBRASKA AND CONTINUE TO EXPAND
ACROSS SOUTHERN PORTIONS OF NORTHWEST IOWA IN PREDAWN HOURS.
HIGH RESOLUTION MODEL SOLUTIONS SUPPORT A HIGHER POP/LOWER QPF
SCENARIO AS BAND WORKS EASTWARD EARLY THIS MORNING...SO BUMPED POPS
UP TO A BRIEF PERIOD OF LIKELY IN FAR SOUTHERN/SOUTHEASTERN CWA...
MAINLY TIMED ALONG WITH MID LEVEL FRONTAL BOUNDARY WHICH DOES HAVE
ENOUGH NEUTRALITY TO STABILITY FIELDS TO SUPPORT CONTRACTING BAND
OF PRECIP THIS MORNING. THIS AREA SHOULD BE PRIMARILY OUT OF THE CWA
BY VERY LATE MORNING. MEANWHILE...LIGHT PRECIP CURRENTLY ACROSS
WESTERN SOUTH DAKOTA INDICATIVE OF THE LIFT FORCING WITH SECONDARY
ENERGY COMING OUT OF WYOMING. THIS PRECIP SHOULD APPROACH SOUTH
CENTRAL SOUTH DAKOTA LOCATIONS BY MID MORNING. FORTUNATELY...
TEMPERATURES SHOULD BE INCREASING BACK ABOVE FREEZING AS PRECIP
MOVES IN...AND ALSO THE OVERALL FORCING WILL START TO DIMINISH SOME
AS WORK INTO THE AFTERNOON HOURS...LIMITING COVERAGE AND INTENSITY
TO TRAILING PRECIP. THIS ROUND OF DYNAMICS HAS MORE FOCUS TOWARD THE
MISSOURI VALLEY...AND SHIFTED THE LOWER POP THREAT FOR THIS
PRECIPITATION SOUTHWARD FROM EARLIER FORECAST.
OTHER GOOD NEWS IS THAT THE OVERALL WIND GRADIENT SHOULD NOT BE
QUITE AS STRONG AS MODELS INDICATED THIS TIME YESTERDAY...AND THIS
SHOULD KEEP WINDS SPEEDS FROM REACHING ADVISORY CRITERIA DURING THE
LATER MORNING AND AFTERNOON. LIKELY TO GET A FEW 35-40 MPH GUSTS
THROUGH THE MISSOURI RIVER CORRIDOR...ESPECIALLY TOWARD LOWER BRULE
AREAS.
AS GO INTO TONIGHT...GRADIENT WILL START TO GRADUALLY DIMINISH...
SOMEWHAT QUICKER IN WESTERN AREAS DURING THE EVENING. SKIES WILL
ALSO TREND TOWARD MORE CLEARING SOUTH AND WEST...AS NORTHWEST FLOW
CONTINUES TO DUMP STRATUS THROUGH THE NORTHEAST HALF OF THE AREA
OVERNIGHT. QUITE A BIT OF SUBSIDENCE INDICATED WHICH SHOULD START
TO MAKE AREA MORE RAGGED BY VERY LATE NIGHT. TEMPS WILL COOL
ACCORDINGLY...WITH THE WEAKER GRADIENT IN THE WEST AND DRY AIR IN
RIDGE FOR SOME UPPER TEENS...WITH MAINLY LOWER TO MID 20S ELSEWHERE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 412 AM CST SUN NOV 17 2013
WE SEE A RETURN TO SOUTHERLY FLOW AND WARMING ALOFT ON
MONDAY...SETTING UP A MILD DAY. IN A SIMILAR TYPE PATTERN THIS PAST
WEEK THE WARMEST GUIDANCE WAS THE WAY TO GO...SO KEPT THAT TREND
GOING WITH HIGHS IN THE 40S AND 50S. THE UNSEASONABLE WARMTH WILL
CONTINUE INTO TUESDAY...WITH ANOTHER DAY OF READINGS IN THE 50S.
WILL LIKELY SEE INCREASING HIGH AND MID CLOUDS THROUGH THE DAY AS AN
UPPER WAVE MOVES ACROSS THE AREA. THESE CLOUDS MAY TEMPER THE
WARMING SOMEWHAT SO DID NOT WANT TO GO TOO HIGH...ALTHOUGH IF CLOUDS
END UP THINNER OR LESS WIDESPREAD...TEMPERATURES WOULD PROBABLY END
UP A FEW DEGREES WARMER THAN CURRENTLY FORECAST. TUESDAY NIGHT WILL
BE A RELATIVELY MILD ONE WITH LOWS IN THE 30S AND 40S...WITH CLOUD
COVER AND A SOUTHERLY BREEZE OUT AHEAD OF OUR NEXT COLD FRONT.
PRETTY GOOD AGREEMENT ON THE COLD FRONT COMING ACROSS WEDNESDAY
MORNING. COLD AIR ALOFT LAGS THE SURFACE FRONT A BIT...WHICH
COMBINED WITH INCREASED MIXING BEHIND THE FRONT...WILL LEAD TO
ANOTHER MILD DAY...ESPECIALLY ACROSS OUR EAST. THUS WENT AHEAD AND
RAISED HIGHS SOME OVER NORTHWEST IOWA AND PORTIONS OF SOUTHWEST
MINNESOTA. OVERALL EXPECTING 50S THERE...WITH 40S OVER THE NORTHWEST
HALF OF THE AREA. SEEMS LIKE WE WOULD SEE FALLING TEMPERATURES BY
AFTERNOON AS THE STRONG COLD AIR ADVECTION KICKS IN.
MODELS THEN BEGIN TO DIVERGE WEDNESDAY NIGHT INTO THE END OF THE
WEEK. A COMPLEX PATTERN WITH THE COLD AIRMASS ASSOCIATED WITH THE
NORTHERN STREAM WAVE INTERACTING WITH SOUTHERN STREAM ENERGY COMING
INTO CALIFORNIA FROM THE PACIFIC. A LARGE SPREAD IN THE OPERATIONAL
MODELS AND GFS ENSEMBLES CONFIRM THAT THIS IS A LOW PREDICTABILITY
TYPE OF PATTERN. THE ECMWF IS MOST AGGRESSIVE WITH THE NORTHERN
STREAM WAVE...PUSHING COLD AND DRY AIR INTO OUR REGION THURSDAY INTO
FRIDAY. WHILE THE GFS AND GEM ARE NOT QUITE AS AGGRESSIVE...AND RIDE
SOME OF THE SOUTHERN STREAM ENERGY OVER THE BAROCLINIC ZONE
RESULTING IN A PERIOD OF PRECIPITATION FOR US SOMETIME THURSDAY INTO
FRIDAY MORNING. GFS ENSEMBLES OFFER A WIDE ARRAY OF
SOLUTIONS...RANGING FROM A MORE COLD AND DRY ECMWF LIKE
SOLUTION...TO A MUCH FURTHER NORTH...MORE PHASED AND WARMER
SOLUTION. CANT SEE MUCH REASON TO FAVOR ONE IDEA OVER ANOTHER AT
THIS POINT...SO WILL JUST CONTINUE TO MONITOR TRENDS OVER THE COMING
DAYS....NOTING THE POTENTIAL FOR AT LEAST A LIGHT PRECIPITATION
EVENT IN THIS TIME FRAME. WOULD SEEM LIKE WE WOULD TEND TO BE DRY
ON SATURDAY WITH HIGH PRESSURE BUILDING IN AND ANOTHER POTENTIAL
ARCTIC FRONT DIVING SOUTH OUT OF CANADA. MODELS AGAIN JUMPING ALL
OVER THE PLACE WITH REGARDS TO WHETHER THIS COLD SHOT DIVES INTO
THE PLAINS...OR FURTHER EAST INTO THE GREAT LAKES REGION. SO
OVERALL...CONSENSUS TEMPERATURE GUIDANCE WAS PRETTY MUCH ACCEPTED
FROM THURSDAY INTO SATURDAY UNTIL MODEL AGREEMENT AND RUN TO RUN
CONSISTENCY INCREASES. TEMPERATURES SHOULD TEND TO RUN BELOW
NORMAL THIS PERIOD THOUGH...WITH CURRENT CONSENSUS GIVING HIGHS IN
THE 20S AND 30S AND LOWS IN THE TEENS AND 20S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 554 AM CST SUN NOV 17 2013
VERY COMPLEX AVIATION FORECAST THIS MORNING. STRATUS FIELD
OBSCURED FROM VIEW BY HIGHER LEVEL CLOUDS THIS MORNING...MAKING IT
DIFFICULT TO DIAGNOSE COVERAGE OF LOWER CLOUDS/FOG. OBSERVATIONS
INDICATE THERE IS SOME DENSE FOG ALONG THE WESTERN LEADING EDGE OF
AREA...MAINLY THROUGH THE JAMES VALLEY...INCLUDING THE KHON TAF.
THESE CONDITIONS SHOULD NOT LAST LONG...AND HAVE REFLECTED A
SOMEWHAT MORE OPTIMISTIC START WITH 12Z TAF. HRRR HAS PROVIDED
SOME ADEQUATE GUIDANCE AS TO SPREAD OF LOWER CEILINGS...AND
INDICATED THAT MUCH OF THE LIFR CEILINGS SHOULD START TO DIMINISH
BY 16Z TO 17Z. QUESTIONS REMAIN IF ANY WILL BE ABLE TO PUSH SOUTH
INTO KSUX AREA BEFORE MORE MIXY ENVIRONMENT SETS UP AND STRONGER
SUBSIDENCE ERODES ADVANCING CLOUDS. WINDS WILL GUST 25 TO 30 KNOTS
THROUGH THE AFTERNOON HOURS...BEFORE DIMINISHING THIS EVENING.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...CHAPMAN
LONG TERM...CHENARD
AVIATION...CHAPMAN
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
944 AM CST SUN NOV 17 2013
.UPDATE...
UPDATED TO REDUCE MORNING AND AFTERNOON RAIN CHANCES AND TO ADJUST
SEVERE WEATHER WORDING.
&&
.DISCUSSION...
FIRST...CONVECTION WITH THE LOW LEVEL INSTABILITY AXIS MOVING
FASTER EAST THAN PREVIOUSLY FORECASTED...SO HAVE ADJUSTED RAIN
CHANCES ACCORDINGLY FOR THE REMAINDER OF THE MORNING.
SECOND...AFTER ANALYSIS OF THE HRRR MODEL...CURRENT SIGNIFICANT
MIXING IN THE OBSERVATIONS AHEAD OF THE FRONT IN NORTHWEST
ARKANSAS...AND STRONG CAP DEVELOPING AHEAD OF THE FRONT OFF OF
12Z SGF SOUNDING...IT APPEARS THAT THE SEVERE THREAT WILL REMAIN
ACROSS THE NORTHERN AND EASTERN COUNTIES FOR THIS AFTERNOON WHERE
FRONTAL FORCING WILL BE STRONGEST. HELICITY VALUES NEAR 200
M^2/S^2 SUGGESTS WEAK TORNADOES WILL STILL BE POSSIBLE...THOUGH
DAMAGING WIND GUSTS IS STILL THE PRIMARY SEVERE THREAT. HAVE
ADJUSTED THE HWO ACCORDINGLY.
THIRD...MADE SOME ADJUSTMENTS TO AFTERNOON CLOUD COVER AS MORE BREAKS
IN THE LOW LEVEL MOISTURE IS ANTICIPATED...AIDING THE SOUTH TO
SOUTHWEST WINDS TO REACH THE WIND ADVISORY CRITERIA EAST OF THE MS RIVER.
JAB
&&
.PREV DISCUSSION... /ISSUED 523 AM CST SUN NOV 17 2013/
DISCUSSION... /ISSUED 458 AM CST SUN NOV 17 2013/
EARLY MORNING GOES WATER IMAGERY SHOWED A DEEP UPPER LEVEL TROF
OVER THE CENTRAL AND NORTHERN PLAINS. THIS FEATURE WAS LIFTING
EAST AND BECOMING NEGATIVELY TILTED. A 160KT 200MB JET EXTENDED
FROM NORTH TX ACROSS THE OZARK PLATEAU...WITH INCREASINGLY
DIFFLUENT FLOW EVIDENT DOWNSTREAM OF THE JET CORE. CLOSER TO
HOME... THUNDERSTORMS HAD FORMED ON THE SOUTHERN FLANK OF THE JET
CORE OVER NORTHERN AR...INTO WEST TN. THIS CONVECTION WAS ROOTED
IN AN ELEVATED LAYER...THUS FAR UNABLE TO TAP INTO THE GREATER
HELICITY EMBEDDED IN A WEAK NOCTURNAL INVERSION BELOW 925MB.
EXPECT THE SHOWERS AND THUNDERSTORMS TO SHIFT EASTWARD THROUGH THE
DAY PERHAPS LEAVING AREAS WEST OF THE RIVER FREE OF RAIN LATER THIS
MORNING.
LATE MORNING AND EARLY AFTERNOON SEVERE CHANCES WILL LIKELY DEPEND
ON STORMS BECOMING ROOTED IN THE BOUNDARY LAYER... TAPPING BETTER
DIRECTIONAL SHEAR FOR MORE PERSISTENT AND ORGANIZED STORM STRUCTURES.
NAM BUFR SOUNDINGS SUGGESTS THIS IS A DISTINCT POSSIBILITY...PARTICULARLY
IN THE 18Z TO 21Z TIME FRAME. STORMS WILL HAVE BETTER CHANCES OF
BECOMING SURFACED BASED WITH THE ARRIVAL OF A SURFACE COLD FRONT
INTO EASTERN AR AROUND 21Z/3PM. STORMS MAY REFORM AS FAR WEST AS
JONESBORO...FORMING A LINE THAT WILL PROGRESS SOUTHEAST INTO THE
NORTHEAST MS TOWARD 03Z/9 PM. MAIN SEVERE WEATHER THREAT ACROSS
THE MIDSOUTH WILL DAMAGING STRAIGHT LINE WINDS. 06Z NAM PROGGED
700MB WEST/SOUTHWEST WINDS OF 60 TO 75 KTS NORTH OF I40 THIS
AFTERNOON...PERHAPS LEADING TO SOME BOWING LINE SEGMENTS. THERE
WILL BE SUFFICIENT HELICITY AND CAPE FOR SECONDARY TORNADO
THREAT DURING THE MID TO LATE AFTERNOON.
THE NAM PROGGED 03Z/9PM SURFACE CAPE NEAR 1000 J/KG AND 3KM
HELICITY NEAR 300 M2/S2 AT TUPELO. STORMS ALONG THE ADVANCING COLD
FRONT WILL HAVE A SHOT AT BECOMING ROOTED IN THE BOUNDARY LAYER.
OTHERWISE...HIGHER CINH AND LOWER ELEVATED CAPE SHOULD PREVAIL
OVER NORTH MS AS THE NOCTURNAL INVERSION FORMS.
TRANQUIL WEATHER WILL PREVAIL MONDAY THROUGH WEDNESDAY...COURTESY
OF PACIFIC SURFACE HIGH PRESSURE AND ZONAL FLOW ALOFT. GFS AND
ECMWF HAVE COME INTO BETTER AGREEMENT WITH RESPECT TO THE SPLIT
UPPER LEVEL FLOW PATTERN LATE IN THE WEEK. BY THURSDAY...MIDLEVEL
PACIFIC SUBTROPICAL MOISTURE WILL ACCOMPANY MODEST LOW LEVEL WARM
ADVECTION TO SUPPORT A RETURN OF SCATTERED SHOWERS TO THE MIDSOUTH.
BY LATE FRIDAY... COLLAPSING HEIGHTS OVER THE GREAT LAKES AND UPPER
MIDWEST WILL DRIVE A SURFACE COLD FRONT THE MIDSOUTH LATE FRIDAY.
COOLER AND MUCH DRIER MODIFIED ARCTIC AIR WILL SPREAD IN SATURDAY...
WITH MIDLEVEL CLOUDS AND MOISTURE LIKEWISE PUSHING OFF TO THE
SOUTH...INTO THE NORTHERN GULF OF MEXICO. NEXT WEEKEND/S WEATHER
SHOULD BE MORE TYPICAL OF LATE NOVEMBER.
PWB
&&
.AVIATION...
12Z TAF SET
IFR CIGS STILL HAVE YET TO MATERIALIZE EXCEPT AT KTUP. AREA OF
SHRAS WITH EMBEDDED TSRAS CONTINUES TO DEVELOP AND PUSH EAST
ACROSS THE CWA. CAN/T RULE OUT CIGS LOWERING TO IFR UNDERNEATH THE
HEAVIER SHRAS/TSRAS...OTHERWISE EXPECT MVFR CONDITIONS TO PREVAIL
THROUGH MUCH OF THE DAY AGAIN WITH THE POSSIBLE EXCEPTION OF KTUP.
WOULD NOT BE SURPRISED TO SEE CONDITIONS RETURN TO VFR AT
LOCATIONS SUCH AS KMEM AND KJBR THIS AFTERNOON. REDEVELOPMENT OF
TSRAS IS EXPECTED ALONG THE FRONT THIS AFTERNOON INTO THIS
EVENING. BEST CHANCES WILL OCCUR AT KMKL AND KTUP BETWEEN 23Z-05Z.
SKIES WILL QUICKLY CLEAR BEHIND THE FRONT. STRONG S TO SW WINDS
EXPECTED TODAY WITH SUSTAIN SPEEDS OF 10-17 KTS WITH GUSTS BETWEEN
15-28 KTS. WINDS WILL TURN AROUND TO THE NW AND EVENTUALLY N
BEHIND THE FRONT. SPEEDS WILL DIMINISH TO BETWEEN 5-10 KTS AS WELL
DURING THE OVERNIGHT HOURS.
KRM
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 78 46 62 40 / 100 20 0 0
MKL 76 41 61 34 / 100 30 0 0
JBR 79 42 60 35 / 60 10 0 0
TUP 76 46 65 37 / 100 40 0 0
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WIND ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR CLAY-CRAIGHEAD-
CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI-
PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...WIND ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR DUNKLIN-PEMISCOT.
MS...WIND ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR ALCORN-BENTON MS-
CALHOUN-COAHOMA-DESOTO-LAFAYETTE-MARSHALL-PANOLA-PONTOTOC-
QUITMAN-TALLAHATCHIE-TATE-TIPPAH-TUNICA-UNION-YALOBUSHA.
TN...WIND ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR CARROLL-CHESTER-
CROCKETT-DECATUR-DYER-FAYETTE-GIBSON-HARDEMAN-HARDIN-
HAYWOOD-HENDERSON-HENRY-LAKE-LAUDERDALE-MADISON-MCNAIRY-
OBION-SHELBY-TIPTON-WEAKLEY.
&&
$$
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1108 AM EST SUN NOV 17 2013
...DENSE SEA FOG OFF THE COAST OF FAR NORTH COASTAL GEORGIA AND
FAR SOUTH COASTAL SOUTH CAROLINA...
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE TO BUILD INTO THE REGION FROM THE
NORTHEAST THROUGH TONIGHT. A STRONG COLD FRONT WILL THEN MOVE
THROUGH LATE MONDAY FOLLOWED BY COLDER HIGH PRESSURE BUILDING FROM
THE NORTH THROUGH THE MIDDLE OF THE WEEK. ANOTHER COLD FRONT COULD
MOVE THROUGH SATURDAY WITH HIGH PRESSURE RETURNING FOR THE END OF
NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ISENTROPICALLY INDUCED SHOWER ACTIVITY HAS BEEN DIMINISHING OVER
THE PAST TWO HOURS. SHORT TERM GUIDANCE IS NOT OVERLY EXCITED
ABOUT THE PROSPECTS FOR MEASURABLE RAINFALL THROUGH EARLY
AFTERNOON ANYWHERE ACROSS SOUTHEAST SOUTH CAROLINA AND SOUTHEAST
GEORGIA...HOWEVER RAP ISENTROPIC FIELDS SHOW MODEST 295-305K
ISENTROPIC ASSENT GOING THROUGH THE DAY. WILL LOWER POPS OUT OF
THE LIKELY CATEGORY INTO THE MID-RANGE CHANCE CATEGORY ACROSS THE
SOUTH BASED ON CURRENT RADAR DATA. THERE ARE SOME SIGNALS THAT A
LOOSELY CONCENTRATED AREA OF SHOWERS COULD BRUSH THE CHARLESTON
METRO AREA BY EARLY AFTERNOON...BUT AGAIN...MODELS ARE NOT OVERLY
IMPRESSED. WILL SHOW 30-40 PERCENT POPS AREA WIDE TODAY...WITH
INCREASING POPS ACROSS THE NORTH AS MORE ORGANIZED SHOWER ACTIVITY
ATTEMPTS TO APPROACH THE SOUTH CAROLINA ZONES LATER THIS AFTERNOON
AS SHORTWAVE ENERGY APPROACHES.
EXTENSIVE CLOUD COVER WILL LIMIT HIGHS SOMEWHAT TODAY...ALTHOUGH
PRE-FRONTAL COMPRESSIONAL HEATING AND ONGOING WARM AIR ADVECTION
COULD COUNTERACT THE LACK OF STRONG INSOLATION. WILL MAINTAIN
HIGHS IN THE MID 70S FOR NOW.
THE REMAINDER OF THE FORECAST IS ON TRACK.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
TONIGHT...A SOUTH-SOUTHWEST FLOW AHEAD OF AN APPROACHING COLD
FRONT FROM THE NORTHWEST WILL KEEP DEEP LAYERED MOISTURE IN PLACE
ACROSS THE REGION. PRE-FRONTAL SHOWERS ARE EXPECTED TO OCCUR AND
THE FORECAST SHOWS A CHANCE OF SHOWERS FOR THE ENTIRE FORECAST
AREA. HAVE REMOVED THE MENTION OF THUNDERSTORMS DUE TO LIMITED
INSTABILITY BECAUSE OF NOCTURNAL COOLING. IT SHOULD BE A
RELATIVELY WARM NIGHT GIVEN THE SOUTH-SOUTHWEST FLOW AND EXTENSIVE
CLOUD COVER...WITH LOWS FORECAST IN THE MID 60S IN MOST AREAS.
MONDAY THROUGH WEDNESDAY...A COLD FRONT IS SLATED TO APPROACH
FROM THE WEST MONDAY MORNING AND THEN SLOWLY PUSH TOWARD THE COAST
DURING THE AFTERNOON...ALTHOUGH THERE IS STILL SOME UNCERTAINTY
REGARDING THE TIMING OF THIS FEATURE. OVERALL WE THINK THE BEST
RAIN CHANCES WILL COME IN THE MORNING WHEN THE DEEPEST MOISTURE
WILL BE IN PLACE...BUT THE NAM12 RE-FIRES SOME CONVECTION IN THE
AFTERNOON ALONG AND AHEAD OF A SLOWER-MOVING FRONT AS TEMPERATURES
WARM TO NEAR 80 DEGREES. THUS...WOULD NOT BE SURPRISED TO SEE A
FEW GUSTY THUNDERSTORMS DURING THE AFTERNOON IF THE FRONT IS
INDEED SLOWER TO PASS THROUGH. MUCH DRIER AND COOLER AIR WILL PUSH
IN FROM THE NORTH MONDAY NIGHT BEHIND THE FRONT...CONTINUING
THROUGH WEDNESDAY. THIS WILL LEAD TO BREEZY NORTH/NORTHEAST WINDS
TUESDAY AND WEDNESDAY...ESPECIALLY ALONG THE COAST.
LAKE WINDS...SMALL RISK FOR LOW-END ADVISORY CONDITIONS DEVELOPING
ON LAKE MOULTRIE LATE MONDAY NIGHT INTO EARLY TUESDAY AS STRONG HIGH
PRESSURE BUILDS IN FROM THE NORTH.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
COOL/DRY HIGH PRESSURE WILL PERSIST NORTH OF THE AREA THROUGH THE
MIDDLE OF THE WEEK BEFORE BREAKING DOWN LATE IN THE WEEK AS A COLD
FRONT APPROACHES. THERE IS NOW MUCH BETTER AGREEMENT BETWEEN THE GFS
AND ECMWF SHOWING THE FRONT PUSHING THROUGH SATURDAY WITH
COOLER/DRIER HIGH PRESSURE BUILDING BACK IN FOR THE END OF THE
WEEKEND. OTHERWISE...IT WILL BE BREEZY THROUGH MID WEEK DUE TO THE
TIGHT PRESSURE GRADIENT...WITH HIGHEST WINDS CLOSER TO THE COAST.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
GIVEN EXPANSIVE MID AND UPPER LEVELS CLOUDS...THE THREAT FOR FOG
HAS ENDED AT THE TERMINALS THIS MORNING.
KCHS...VFR CONDITIONS ARE EXPECTED TO PREVAIL TODAY...ALTHOUGH
THERE IS THE POTENTIAL FOR CEILINGS TO DROP TO MVFR LEVELS AT
TIMES. SCATTERED SHOWERS ARE EXPECTED TO DEVELOP THIS AFTERNOON
AND PERSIST INTO EARLY THIS EVENING AS A DISTURBANCE CROSSES THE
REGION...THUS HAVE INCLUDED VICINITY SHOWERS IN THE TAF/S FROM
18-02Z. MODELS ARE IN FAIRLY GOOD AGREEMENT INDICATING THE
POTENTIAL FOR IFR CEILINGS AND MVFR VISIBILITIES FROM ABOUT 02Z
THROUGH THE END OF THE FORECAST PERIOD AT 12Z MONDAY.
KSAV...STRATUS ACROSS SOUTHERN GEORGIA WILL LIFT NORTHWARD THIS
MORNING AND IS EXPECTED TO IMPACT THE TERMINAL FROM ABOUT 14-18Z.
DURING THIS TIME...THE TAF INDICATES PREVAILING MVFR CEILINGS WITH
TEMPORARY IFR CEILINGS FROM 14-16Z. THEN...CEILINGS SHOULD LIFT TO
LOW-END VFR LEVELS THROUGH THE REMAINDER OF THE DAY...ALTHOUGH
THEY COULD DROP TO MVFR LEVELS AT TIMES. SCATTERED SHOWERS ARE
EXPECTED TO DEVELOP THIS AFTERNOON AND PERSIST INTO EARLY THIS
EVENING AS A DISTURBANCE CROSSES THE REGION...THUS HAVE INCLUDED
VICINITY SHOWERS IN THE TAF/S FROM 18-02Z. MODELS ARE IN FAIRLY
GOOD AGREEMENT INDICATING THE POTENTIAL FOR IFR CEILINGS AND MVFR
VISIBILITIES FROM ABOUT 02Z THROUGH THE END OF THE FORECAST PERIOD
AT 12Z MONDAY.
EXTENDED AVIATION OUTLOOK...MVFR...POSSIBLY IFR...CONDITIONS MON
ALONG AND AHEAD OF A COLD FRONT. OTHERWISE...MAINLY VFR THROUGH
FRIDAY...ALTHOUGH BREEZY/GUSTY CONDITIONS ARE EXPECTED
TUESDAY/WEDNESDAY AND POSSIBLY THURSDAY.
&&
.MARINE...
TODAY...TYBEE ISLAND WEBCAMS AND REPORTS FROM THE TYBEE ISLAND
COAST GUARD INDICATE AN AREA OF DENSE SEA FOG HAS DEVELOPED FROM
ROUGHLY HILTON HEAD SOUTH TO SAINT CATHERINES SOUND. ITS UNCLEAR
HOW FAR OFFSHORE THE FOG EXTENDS WITH MID-LEVEL CLOUDS BLOCKING
VIEWS FROM SATELLITE...BUT HAVE HOISTED A MARINE DENSE FOG
ADVISORY FOR THE GEORGIA NEARSHORE WATERS AND THE FAR SOUTHERN
SOUTH CAROLINA NEARSHORE WATERS UNTIL 4 PM EST.
A COASTAL TROUGH WILL DISSIPATE EAST OF THE WATERS...ALLOWING
A RETURN FLOW TO DEVELOP ALONG THE PERIPHERY OF HIGH PRESSURE
NORTHEAST OF THE REGION. THIS WILL CAUSE WINDS TO GRADUALLY VEER
SOUTHEAST OR SOUTH THROUGH THE DAY. WIND SPEEDS WILL GENERALLY BE
AROUND 10 KT OR LESS DUE TO THE LACK ANY SIGNIFICANT PRESSURE
GRADIENT. SEAS WILL REMAIN IN THE 2-4 FT RANGE.
TONIGHT...A SOUTH-SOUTHWEST FLOW WILL STRENGTHEN TO AS MUCH AS
10-15 KT IN ADVANCE OF AN APPROACHING COLD FRONT FROM THE
NORTHWEST. SEAS WILL BUILD BY ABOUT A FOOT OR SO AS A RESULT.
PERHAPS THE BIGGEST CONCERN TONIGHT IS FOR THE POTENTIAL FOR SEA
FOG TO FORM AS DEWPOINTS SURGE IN THE UPPER 60S ON THE
STRENGTHENING SOUTHERLY FLOW. GIVEN CONSIDERABLY COOLER SEA SURFACE
TEMPERATURES...THIS WILL RESULT IN CONDITIONS FAVORABLE FOR SEA
FOG TO FORM OR ADVECT IN FROM THE SOUTH TONIGHT AND COULD REDUCE
VISIBILITIES ENOUGH TO WARRANT A DENSE FOG ADVISORY FOR PORTIONS
OF THE NEAR SHORE COASTAL WATERS AND CHARLESTON HARBOR.
MONDAY THROUGH FRIDAY...A COLD FRONT WILL PUSH THROUGH LATE MONDAY
WITH WINDS/SEAS INCREASING GREATLY MONDAY NIGHT FROM THE NORTH AS
STRONG HIGH PRESSURE BUILDS INTO THE OHIO VALLEY. SOLID SMALL CRAFT
ADVISORY CONDITIONS ARE ANTICIPATED FOR ALL WATERS INTO THURSDAY
WITH THE POTENTIAL FOR GALE FORCE WINDS...MAINLY BEYOND 20 NM FROM
SHORE.
INCREASING LOW-LEVEL MOISTURE ATOP THE RELATIVELY COOL NEARSHORE
WATERS COULD PRODUCE SOME SEA FOG MONDAY UNTIL THE FRONT PUSHES
THROUGH.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...DENSE FOG ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR AMZ352-
354.
&&
$$
ST
AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
1056 AM CST SUN NOV 17 2013
.MESOSCALE DISCUSSION...
1055 AM CST
CONVECTION CONTINUES TO BLOSSOM ACROSS CENTRAL INTO NORTHERN IL
WITH THE CWA FULL ENTRENCHED IN THE UNCAPPED WARM SECTOR.
CONVECTIVE MODE CONTINUES TO BE QUICKLY DEVELOPING CELLS WITH
EMBEDDED ROTATION. WHILE MANY CELLS ARE NOT TRULY DISCRETE THEY
ARE MAINTAINING SUPERCELL CHARACTERISTICS. ANTICIPATED THAT MORE
TRULY DISCRETE CONVECTION WILL DEVELOP IN THE NEXT 1-2 HOURS INTO
THE SOUTHEAST HALF/TWO-THIRDS OF THE FORECAST AREA...WHICH IS
WHERE THE RAP IS CONTINUING TO KEEP 0-1KM SHEAR AT 35-45 KT.
THE POTENTIAL FOR TORNADOES...SOME SIGNIFICANT...LOOKS TO BE
RAPIDLY INCREASING THERE. THE CHICAGO AREA IS INCLUDED IN THIS.
ALREADY SEEING SOME OF THESE DISCRETE CELLS IN THE ILX CWA.
MOVEMENT WILL BE RAPIDLY TO THE NORTHEAST. THE CHICAGO AREA STILL
LOOKS TO BE IMPACTED PRIMARILY BETWEEN 12PM- 3PM. FURTHER NORTH
AND WEST TOWARD ROCKFORD THE SEVERE WEATHER THREAT REMAINS HIGH
EVEN WITH DIMINISHING LOW-LEVEL SHEAR...WITH PRIMARY THREATS WINDS
AND TORNADOES.
MTF
&&
.DISCUSSION...
304 AM CST
HIGH SEVERE WEATHER POTENTIAL ACROSS MUCH OF THE AREA TODAY WITH
TORNADOES AND DAMAGING STRAIGHT LINE WINDS A SIGNIFICANT THREAT.
SYNOPSIS...NEAR TERM FOCUS CONTINUES TO BE SEVERE WEATHER THREAT AS
A MAJOR FALL STORM SYSTEM TAKES SHAPE AND MOVES ACROSS THE REGION.
WATER VAPOR IMAGERY SHOWS A BROAD UPPER TROUGH PIVOTING ACROSS THE
MID SECTION OF THE COUNTRY WITH EVENING UPPER AIR ANALYSIS SHOWING A
150 KT UPPER JET DIGGING DOWN ITS WESTERN FLANK. AT THE SAME TIME A
SUB TROPICAL JET OF AROUND 120 KT IS STRETCHED FROM OKLAHOMA UP THE
OHIO VALLEY. SEVERAL SHORTWAVES ARE EMBEDDED IN THE SOUTHWESTERLY
FLOW AHEAD OF THE TROUGH WI ONE WAVE CROSSING NORTHWEST ILLINOIS
EARLY THIS MORNING AND A HINT OF ANOTHER ACROSS EASTERN KANSAS. AT
THE SURFACE...ONE AREA OF LOW PRESSURE IS STRETCHED FROM NORTHERN
MINNESOTA ACROSS LAKE SUPERIOR WITH ANOTHER LOW MOVING NORTHEAST
FROM CENTRAL KANSAS. SYNOPTICALLY...THE UPPER TROUGH WILL AMPLIFY AS
THE UPPER JET ROUNDS THE BASE WITH IT TAKING ON A NEGATIVE TILT AS
IT PIVOTS ACROSS THE LOCAL AREA THROUGH THE AFTERNOON. THIS WILL
CAUSE THE SURFACE LOW OVER KANSAS TO CONTINUE NORTHEAST REACHING
SOUTHERN WISCONSIN BY EARLY AFTERNOON. THE LOW WILL THEN DEEPEN AS
THE UPPER TROUGH AMPLIFIES AND CATCHES UP WITH IT ACROSS NORTHERN
LAKE MICHIGAN LATE THIS AFTERNOON. A COLD FRONTAL BOUNDARY WILL
CROSS THE AREA DURING THE AFTERNOON.
DETAILS FOR TODAY...CONVECTION CONTINUES TO WORK NORTHWARD ACROSS
THE NORTHWEST HALF OR SO OF THE AREA EARLY THIS MORNING IN
CONJUNCTION WITH THE AFOREMENTIONED SHORTWAVE. THIS WAVE IS
COINCIDENT WITH A TIGHTENING LOW/MID LEVEL BAROCLINIC ZONE/WARM
FRONT THAT IS LIFTING NORTHWARD. STEADY ASCENT WILL CONTINUE OVER
THIS BOUNDARY WHICH WILL PROGRESS NORTHWARD THROUGH DAYBREAK KEEPING
AT LEAST SCATTERED CONVECTIVE DEVELOPMENT POSSIBLE ACROSS THE
NORTHERN CWA BEFORE LIFTING NORTH. HAVE NOT SEEN MUCH IN THE WAY OF
WIND GUSTS WITH THE PRECIP THUS FAR WITH INTENSITY HAVING WANED INTO
THE OVERNIGHT HOURS...BUT SOME PULSEY CORES ARE POSSIBLE WITH SOME
SMALL HAIL. SATELLITE IMAGERY SHOWS A FAIR AMOUNT OF SCT-BKN SKIES
UPSTREAM OF THE AREA WITH A MORE WIDESPREAD AREA OF CLOUDS WORKING
NORTHWARD TO THE WEST OF THE CWA. SUSPECT THAT THERE WILL BE BREAKS
IN THE CLOUDS ACROSS PORTIONS OF THE CWA THIS MORNING.
ATTENTION TURNS TO SEVERE POTENTIAL THROUGH THE REST OF THE DAY AS
THE ABOVE SYNOPTIC EVOLUTION COMMENCES. BOTH DYNAMIC AND
THERMODYNAMIC ASPECTS OF THE SYSTEM ARE IMPRESSIVE AND WILL COME
TOGETHER TO PRODUCE AN OUTBREAK OF SEVERE WEATHER ACROSS THE REGION.
THE MAIN QUESTION FOR THE LOCAL AREA WILL BE THE AMOUNT OF COVERAGE
AS THE SYSTEM WORKS THROUGH INTO THE LATE AFTERNOON. THE WESTERN
UPPER JET WILL ROUND THE BASE OF THE TROUGH AND NOSE INTO THE AREA
FROM THE SOUTHWEST DURING THE LATE MORNING AND EARLY AFTERNOON. THIS
JET WILL ALSO COUPLE WITH THE SUB-TROPICAL JET ALREADY IN PLACE
ACROSS THE OHIO VALLEY. IN ADDITION...A 85-90 KT MID LEVEL SPEED MAX
WILL NOSE IN UNDERNEATH THE UPPER JET DURING THIS TIME AS WELL. THE
COMBINATION OF THESE FEATURES AND THE DEEPENING SURFACE TROUGH WILL
PROVIDE DEEP LAYER SHEAR VALUES OF 55-60 KT ACROSS MUCH OF THE AREA
BY MIDDAY...WITH AN INCREASE TO NEAR 70 KT ACROSS THE SOUTHEASTERN
CWA THIS AFTERNOON...WITH 0-1KM SHEAR VALUES OF AROUND 40 KT.
UNSEASONABLY STRONG INSTABILITY WILL DEVELOP AS DEW POINTS RISE INTO
THE LOWER 60S WITH CAPE VALUES OF AROUND 1000 J/KG. FORECAST
SOUNDINGS SHOW HIGH VALUES OF LOW LEVEL CAPE WITH 150 TO EVEN 200
J/KG IN THE LOWEST 3 KM. ALL OF THIS RESULTS IN IMPRESSIVE VALUES
FOR VARIOUS SEVERE WEATHER PARAMETERS. BASED ON ALL OF THIS EXPECT
THAT STORMS WILL INITIATE BY LATE MORNING OVER OR JUST SOUTHWEST/WEST OF
THE SOUTHWEST CWA AS THE ABOVE SYNOPTIC FEATURES ADVANCE NORTHEAST.
COVERAGE OF STORMS LOOKS TO TAKE OFF EARLY THIS AFTERNOON AS THE
COUPLING OF THE MID/UPPER JETS MAXIMIZES AND CONTINUES THROUGH THE
AFTERNOON. THE SEVERE THREAT WILL MARKEDLY INCREASE AS THIS OCCURS
AS WELL. THE RATE AT WHICH COVERAGE INCREASES IS STILL SOMEWHAT
UNCERTAIN...AT LEAST THROUGH MIDDAY...WITH IT POSSIBLE THAT A FEW
STORMS DEVELOP INITIALLY WITH A MORE RAPID INCREASE HOLDING OFF
UNTIL EARLY AFTERNOON WITH THE ARRIVAL OF BETTER FORCING. THE MYRIAD
OF AVAILABLE CONVECTIVE ALLOWING GUIDANCE RUNS THE GAMUT OF COVERAGE
SCENARIOS. THE LATEST SPC DAY 1 OUTLOOK LINES UP WELL WITH LOCAL
THINKING PLACING THE HIGHEST RISK FROM BASICALLY CHICAGO SOUTH TO
FORD COUNTY AND POINTS EAST. THIS AREA WILL LINE UP WELL WITH THE
BEST FORCING PARAMETERS AND TIMING OF INCREASING COVERAGE THIS
AFTERNOON. THE REMAINDER OF THE CWA TO THE WEST INCLUDING THE
ROCKFORD AREA IS IN A MODERATE RISK AND MAY BE MORE IN LINE WITH THE
INITIAL DEVELOPMENT. AS FAR AS THREATS...THE STRONG SHEAR AND
INSTABILITY WILL POINT TO DISCRETE SUPERCELL DEVELOPMENT WITH AN
EVENTUAL EVOLUTION INTO A SQUALL LINE LATER TODAY. IT IS POSSIBLE
THAT MUCH OF THE ACTIVITY REMAINS FAIRLY DISCRETE ACROSS THE CWA
WITH EVOLUTION INTO A PREDOMINATELY LINEAR STRUCTURE TAKING PLACE
OVER OR JUST EAST OF THE EASTERN CWA. GIVEN THE STRONG LOW LEVEL
SHEAR AND INSTABILITY...TORNADOES ARE A DEFINITE THREAT ALONG WITH
DAMAGING WINDS FOLLOWED BY LARGE HAIL. THE STRONG SHEAR AND
POTENTIAL FOR MAINTENANCE OF DISCRETE CELLS SUGGEST THE POTENTIAL
FOR STRONGER AND LONGER TRACKED TORNADOES SHOULD THEY OCCUR.
THE OTHER HIGHLIGHT IS THE SYNOPTIC NON-THUNDERSTORM WINDS.
SOUTHERLY SPEEDS WILL INCREASE THROUGH THE MORNING...ESPECIALLY IF
ANY MEANINGFUL CLEARING CAN OCCUR AS PRESSURE FALLS INCREASE AHEAD
OF THE LOW. THE BIGGEST CONCERN HOWEVER IS WINDS BEHIND THE COLD
FRONT WHICH WILL CROSS THE AREA LATER THIS AFTERNOON. THE STRONG
GRADIENT AND ASSOCIATED PRESSURE RISES ARE EXPECTED TO ALLOW FOR
STRONG MIXING AND GENERATION OF WIND GUSTS THAT COULD TOP 50 KT
ACROSS MUCH OF THE CWA...ESPECIALLY FROM THE NORTHERN CHICAGO
SUBURBS BACK TOWARDS THE MENDOTA AREA AND POINTS SOUTH. HAVE
UPGRADED THIS PORTION OF THE WIND ADVISORY TO A HIGH WIND WARNING
THIS AFTERNOON STARTING TOWARD MIDDAY...WITH THE HIGHEST
WINDS...OUTSIDE OF STORMS...THIS AFTERNOON.
MDB
TONIGHT THROUGH SATURDAY...
LOW PRESSURE WILL QUICKLY BE LIFTING ACROSS THE NORTHERN LAKES
THIS EVENING AND INTO WESTERN QUEBEC MONDAY MORNING...WHILE STILL
DEEPENING WHILE HIGH PRESSURE STRENGTHENS ACROSS THE PLAINS
TONIGHT AND CONTINUES TO STRENGTHEN AS IT MOVES ACROSS THE OHIO
VALLEY AND SOUTHERN LAKES REGION MONDAY NIGHT. THE STRONGEST
WINDS/GUSTS SHOULD DIMINISH QUICKLY EARLY THIS EVENING BUT IT WILL
REMAIN WINDY THROUGH THE EARLY MORNING HOURS...GRADUALLY
DIMINISHING OVERNIGHT. WRAP AROUND SHOWERS WILL BE POSSIBLE FOR A
FEW HOURS THIS EVENING...MAINLY ACROSS FAR NORTHERN IL...THEN
SHOULD SEE CLEARING SKIES. MUCH COLDER AIR WILL SPREAD ACROSS THE
REGION WITH LOWS IN THE MID/UPPER 30S BUT COMBINED WITH THE GUSTY
WESTERLY WINDS...WIND CHILLS WILL RANGE FROM THE MID 20S TO AROUND
30 RANGE BY MORNING.
MONDAY WILL REMAIN BREEZY WITH HIGHS IN THE LOWER/MID 40S WITH
MAINLY SUNNY SKIES. WINDS SHOULD STEADILY DIMINISH FROM MID
AFTERNOON THROUGH SUNSET AS THE HIGH CONTINUES TO BUILD EAST.
LIGHT WINDS AND GENERALLY CLEAR SKIES SHOULD ALLOW FOR A FAST TEMP
DROP MONDAY EVENING WITH THE USUAL COLD SPOTS PERHAPS AS LOW AS
THE LOWER 20S...BUT WITH WEAK WARM AIR ADVECTION OVERNIGHT...TEMPS
MAY LEVEL OFF AT SOME POINT. SOUTHERLY FLOW RETURNS TUESDAY AND
WITH MOSTLY SUNNY SKIES EXPECTED...HIGHS INTO THE UPPER 40S LOOK
REASONABLE WITH GUIDANCE SUGGESTING LOWER 50S COULD BE REACHED
THUS TEMPS COULD BE SLIGHTLY WARMER.
RETURN MOISTURE COMBINED WITH WEAK WAVES LIFTING ACROSS THE AREA
NOW APPEAR SUFFICIENT TO PRODUCE SOME SHOWERS WEDNESDAY INTO
WEDNESDAY NIGHT. THE MODELS ARE IN MUCH BETTER AGREEMENT WITH
THIS SOLUTION BUT STILL SOME TIMING DIFFERENCES AS THE ECMWF HOLDS
OFF PRECIP UNTIL WEDNESDAY NIGHT FOR MUCH OF THE AREA AND A SLOWER
TIMING COULD MEAN WARMER TEMPS ON WEDNESDAY. A COLD FRONT THEN
SAGS SOUTH INTO THE AREA THURSDAY AHEAD OF ANOTHER VERY STRONG
HIGH BUILDING SOUTH INTO THE NORTHERN PLAINS. AS THE UPPER TROUGH
DIGS ACROSS THE LAKES REGION...ANOTHER WAVE MOVES EAST/NORTHEAST
ACROSS THE SOUTHERN LAKES AND OHIO VALLEY. TIMING OF COLDER AIR
ALONG WITH END TIME OF PRECIP ALL REMAIN UNCERTAIN FROM THIS
DISTANCE. CURRENT TRENDS WOULD SUGGEST A COLD RAIN WITH A BRIEF
MIX BEFORE ENDING. HOWEVER...GIVEN THE DIFFERENCES...ITS DIFFICULT
TO LOWER OR RAISE POPS FOR VARIOUS TIME PERIODS. THUS HAVE CHANCE
POPS FOR THE ENTIRE WEDNESDAY NIGHT THROUGH FRIDAY NIGHT TIME
PERIOD AND THERE WILL LIKELY BE PERIODS OF NO PRECIP DURING THIS
TIME. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* SOUTH SOUTHWEST WINDS 20-31 KT INCREASING TO 22-35 KT EARLY
AFTERNOON. THEN SOUTHWEST WINDS 30-50 KT MID AFTERNOON THROUGH
EARLY EVENING. WEST WINDS 20-35 KT OVERNIGHT.
* ISOLATED SHOWERS LATE THIS MORNING. A PERIOD OF STRONG TO SEVERE
THUNDERSTORMS POSSIBLE MID DAY TO MID AFTERNOON.
* MVFR CIGS THROUGH MID AFTERNOON. BRIEFLY IFR CIG/VSBY IN HEAVIER
SHOWERS AND THUNDERSTORMS.
RODRIGUEZ
//DISCUSSION...UPDATED 12Z...
...HIGH WINDS ESPECIALLY MID AFTERNOON TO EARLY EVENING...
...MDT TO HIGH RISK OF SEVERE STORMS LATE MORNING-MID AFTERNOON...
SYNOPSIS AND THUNDERSTORM THREAT...NOT A GOOD DAY FOR FLYING. LOW
PRESSURE NEAR THE IA/MO BORDER THIS MORNING WILL INTENSIFY AS IT
MOVES INTO SOUTH CENTRAL WISCONSIN BY MIDDAY...WITH A STRONG COLD
FRONT SURGING EAST ACROSS NORTHERN IL. THE LOW WILL THEN RAPIDLY
DEEPEN LATE THIS AFTERNOON AND EARLY THIS EVENING AS IT MOVES
ACROSS NORTHERN LAKE MICHIGAN AND THE COLD FRONT SWEEPS INTO
INDIANA. UNSEASONABLY MILD AND HUMID AIR IS SURGING NORTH AHEAD OF
THE LOW...PRODUCING AREAS OF SHOWERS AND A FEW THUNDERSTORMS THIS
MORNING. AS THE LOW INTENSIFIES AND THE ATMOSPHERE
DESTABILIZES...MORE ORGANIZED THUNDERSTORM CLUSTERS WILL DEVELOP
AHEAD OF THE COLD FRONT OVER CENTRAL ILLINOIS AND MOVE RAPIDLY
NORTHEAST. SOME OF THE STORMS WILL PRODUCE DAMAGING WINDS AND EVEN
TORNADOES. THUNDERSTORMS WILL END WITH THE PASSAGE OF THE STRONG
COLD FRONT.
WINDS...SOUTH WINDS ARE IN A LULL EARLY THIS MORNING BUT WILL
RAMP UP TO 20 TO 30 KTS BY LATE MORNING. BEHIND THE COLD FRONT
VERY STRONG PRESSURE RISES WILL PRODUCED SUSTAINED SOUTHWEST WINDS
25 TO 30 KT WITH GUSTS TO AROUND 50 KT. THE STRONGEST WINDS WILL
BE MID AFTERNOON THROUGH EARLY EVENING. WINDS WILL TURN WEST AND
GRADUALLY DIMINISH OVERNIGHT.
CIG/VSBY...LOOKING AT SURFACE OBS AROUND THE AREA THIS
MORNING...CIGS ARE GENERALLY 1000-2000 FT BUT WILL DROP BRIEFLY TO
IFR ESPECIALLY IN HEAVIER SHOWERS AND THUNDERSTORMS. CIG/VSBY WILL
IMPROVE RAPIDLY AFTER THE COLD FRONTAL PASSAGE THIS EVENING...AND
SKIES WILL CLEAR OVERNIGHT.
ALLSOPP
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM TO HIGH CONFIDENCE IN WIND FORECAST.
* MEDIUM CONFIDENCE IN CIG/VSBY TRENDS.
* MEDIUM HIGH CONFIDENCE IN TIMING OF PERIOD OF STRONG STORMS.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR. STRONG WEST WINDS.
TUESDAY...VFR.
WEDNESDAY AND THURSDAY...CHC SHRA. MVFR POSSIBLE.
FRIDAY...CHC RASN. MVFR LIKELY. IFR POSSIBLE.
SATURDAY...VFR.
ALLSOPP
&&
.MARINE...
142 AM CST
...STORM WARNING ISSUED FOR SOUTH 2/3 OF LAKE MI LATE AFTERNOON
AND TONIGHT...
POWERHOUSE STORM WILL INTENSIFY RAPIDLY THIS AFTERNOON AND
TONIGHT AS IT MOVES FROM NORTHERN ILLINOIS TO SOUTHERN ONTARIO.
THERE WILL BE A BIT OF A LULL IN THE WINDS THIS MORNING...AND
WINDS WILL BE JUST BELOW GALE FORCE FOR A BIT BUT WILL MAINTAIN
THE GALE THROUGH MID AFTERNOON. AS THE LOW PRESSURE MOVES ACROSS
THE NORTH END OF THE LAKE THIS AFTERNOON A STRONG COLD FRONT WILL
SWEEP RAPIDLY ACROSS THE LAKE. A LARGE PRESSURE FALL/RISE COUPLET
WILL MOVE ACROSS NORTHERN IL THIS AFTERNOON AND OVER CENTRAL AND
SOUTHERN LAKE MICHIGAN THIS EVENING. EXPECT WINDS TO INTENSIFY
LATE AFTERNOON AND EVENING WITH GUSTS OF 50 TO 60 KTS. NORTH PART
OF THE LAKE MAY SEE SOME NEAR STORM FORCE GUSTS LATE EVENING
THROUGH THE OVERNIGHT HOURS...BUT NOT AS STRONG AS THE SOUTH AND
CENTRAL. SO HAVE MAINTAINED THE GALE FOR THE NORTH. GALES WILL
THEN CONTINUE OVER THE ENTIRE LAKE THROUGH MONDAY AFTERNOON.
FOR THE NEARSHORE...WINDS WILL RAMP UP TO STORM FORCE GUSTS BY
LATE AFTERNOON BUT DROP BACK TO GALES THIS EVENING...SO A SHORTER
PERIOD OF POTENTIAL STORM FORCE WINDS NEARSHORE.
HIGH PRESSURE WILL THEN SETTLE INTO THE AREA FOR MONDAY NIGHT AND
TUESDAY.
ALLSOPP
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...HIGH WIND WARNING...ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 8 PM SUNDAY.
WIND ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-ILZ011-
ILZ012 UNTIL 8 PM SUNDAY.
IN...HIGH WIND WARNING...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 8
PM SUNDAY.
LM...GALE WARNING...LMZ080-LMZ366-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-
LMZ675-LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-
LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 2 PM
SUNDAY.
GALE WARNING...LMZ080-LMZ366-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-
LMZ675-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-
LMZ878...4 AM MONDAY TO 3 PM MONDAY.
STORM WARNING...LMZ080-LMZ366-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-
LMZ675-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-
LMZ878...2 PM SUNDAY TO 4 AM MONDAY.
GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ563 UNTIL 3 PM MONDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...8 PM
SUNDAY TO 4 AM MONDAY.
STORM WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...2 PM
SUNDAY TO 8 PM SUNDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
142 PM EST SUN NOV 17 2013
.UPDATE...
THE LONG TERM DISCUSSION HAS BEEN UPDATED BELOW.
&&
.MESOSCALE UPDATE...
LATEST SURFACE ANALYSIS SHOWS A WARM FRONT THAT
EXTENDS FROM NW INDIANA SSEWD OVER PARKE COUNTY TO NEAR THE
LOUISVILLE AREA. TEMPS IN THE WARM SECTOR ARE INTO THE LOWER 70S.
LOW LEVEL JET IS SWLY WHICH SHOULD PUSH THE WARM FRONT NEWD OVER THE
NEXT TWO HOURS. THIS IS AGREEABLE ANALYZING THE RAP MODEL WHICH
PUTS FAVORABLE INSTABILITY AND SHEAR OVER THE WRN COUNTIES OF
INDIANA BY 19Z. EXPECT STORMS TO DEVELOP OVER WRN SECTIONS OF
INDIANA BY 2PM EST DEVELOPING INTO A DISCRETE LINE AHEAD OF MAIN
COLD FRONT. LOOKS LIKE STORMS WILL SPREAD ACROSS WRN AND CENTRAL
INDIANA BETWEEN 2PM EST AND 7PM EST. EXPECT TORNADOES...LARGE HAIL
AND DAMAGING WINDS TO ACCOMPANY THESE STORMS.
&&
.SYNOPSIS...
ISSUED AT 355 AM EST SUN NOV 17 2013
SEVERE WEATHER IS EXPECTED TODAY WITH MUCH OF CENTRAL
INDIANA BEING IN A HIGH RISK FOR SEVERE WEATHER AS A DYNAMIC AND
STRENGTHENING LOW PRESSURE SYSTEM SWINGS OUT OF THE PLAINS AND
THROUGH THE GREAT LAKES. BY TONIGHT THE COLD FRONT ASSOCIATED WITH
THIS SYSTEM SHOULD BE THROUGH THE AREA AND DRY AIR WILL USHER IN
BEHIND IT. HIGH PRESSURE WILL BUILD IN AND BRING DRY WEATHER THROUGH
MID WEEK. A RAINY PATTERN WILL RETURN FOR THE END OF THE WEEK AND A
COLD FRONT WILL BRING COLD TEMPERATURES IN FOR NEXT WEEKEND.
&&
.NEAR TERM /UPDATE FOR TODAY/...
ISSUED AT 927 AM EST SUN NOV 17 2013
NO SIGNIFICANT CHANGES MADE TO FORECASTS. GUSTS HAVE BEGUN.
INTERMITTENT SUNSHINE WILL ADD TO INSTABILITY. STORM PREDICTION
CENTER HAD EXPANDED HIGH RISK TO NEARLY ALL OF INDIANA BUT NO REAL
CHANGE FOR CENTRAL INDIANA OTHER THAN ADDING EASTERN COUNTIES.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 355 AM EST SUN NOV 17 2013
MODELS SHOW THE COLD FRONT BEING EAST AND SOUTH OF THE FORECAST AREA
BY 0Z TONIGHT...BUT HAVE HELD ONTO POPS IN THE FAR EAST AND SOUTH
FOR THE FIRST FEW HOURS FOR COLLABORATION PURPOSES. BY 3Z HOWEVER
HAVE GONE DRY. AFTER THAT HIGH PRESSURE BUILDS IN FOR THE REMAINDER
OF THE SHORT TERM AND SHOULD SEE MOSTLY CLEAR SKIES AND SLIGHTLY
BELOW NORMAL TEMPERATURES.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
ISSUED AT 142 PM EST SUN NOV 17 2013
EXTENDED MODELS AND ENSEMBLES IN GOOD AGREEMENT THAT SEPARATE
FRONTAL SYSTEMS AND FAST MOIST PACIFIC FLOW ALOFT ARE EXPECTED TO
RESULT IN NORMAL TO SLIGHTLY ABOVE NORMAL TEMPERATURES AND SHOWER
CHANCES WEDNESDAY NIGHT THROUGH SATURDAY. THEN...HIGH PRESSURE WILL
BUILD IN FROM THE CANADIAN PRAIRIES WHICH SHOULD KEEP THE REMAINDER
OF NEXT WEEKEND DRY WITH BELOW NORMAL TEMPERATURES. REGIONAL
ALLBLEND IS HANDLING THINGS WELL.
&&
.AVIATION /DISCUSSION FOR THE 171800Z TAF ISSUANCE/...
ISSUED AT 1127 AM EST SUN NOV 17 2013
STRONG LOW PRESSURE SYSTEM WAS SPAWNING SUPERCELL THUNDERSTORMS
ACROSS ILLINOIS AND MISSOURI LATE THIS MORNING. ADDITIONAL AFTERNOON
SUPERCELL DEVELOPMENT IS EXPECTED ACROSS CENTRAL INDIANA THIS
AFTERNOON FOLLOWED BY A LINE OF SEVERE STORMS. THE BEST TIMING FOR
THE LINE...WHICH WILL BE JUST AHEAD OF THE FRONT...WILL BE IN THE
LAF AND HUF AREAS AROUND 19Z-21Z AND IND AND BMG AROUND 20-22Z.
CONFIDENCE IS GOOD REGARDING THE TIMING OF THIS SQUALL LINE.
SO...WILL START WITH VCTS AND THEN GO WITH TEMPO THUNDERSTORMS FOR 2
HOURS WITH SEVERE GUSTS TO 50 KNOTS FROM THE SOUTHWEST AS STORM
MOTION IS EXPECTED TO BE SOUTHWEST AT 50 KNOTS OR MORE. SOUTH AND
SOUTHWEST GRADIENT WINDS ALONE SHOULD GUST TO 35 KNOTS OR MORE WITH
SUSTAINED WINDS NEAR 25 KNOTS. MVFR AND POSSIBLY IFR CONDITIONS IN
STORMS WILL IMPROVE TO VFR AS THE FRONT MOVES THROUGH WITH CLEARING
LATE IN THE EVENING. SHOULD ONLY SCATTERED DIURNAL CU TOMORROW AFTER
16Z.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 9 PM EST THIS EVENING FOR INZ021-028>031-
035>049-051>057-060>065-067>072.
&&
$$
MESO UPDATE...DWM
SYNOPSIS...CP
NEAR TERM...TUCEK
SHORT TERM...CP
LONG TERM....MK
AVIATION...MK
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
100 PM EST SUN NOV 17 2013
.UPDATE...
ADDED MESOSCALE DISCUSSION.
&&
.MESOSCALE UPDATE...
LATEST SURFACE ANALYSIS SHOWS A WARM FRONT THAT
EXTENDS FROM NW INDIANA SSEWD OVER PARKE COUNTY TO NEAR THE
LOUISVILLE AREA. TEMPS IN THE WARM SECTOR ARE INTO THE LOWER 70S.
LOW LEVEL JET IS SWLY WHICH SHOULD PUSH THE WARM FRONT NEWD OVER THE
NEXT TWO HOURS. THIS IS AGREEABLE ANALYZING THE RAP MODEL WHICH
PUTS FAVORABLE INSTABILITY AND SHEAR OVER THE WRN COUNTES OF INDIANA
BY 19Z. EXPECT STORMS TO DEVELOP OVER WRN SECTIONS OF INDIANA BY
2PM EST DEVELOPING INTO A DISCRETE LINE AHEAD OF MAIN COLD FRONT.
LOOKS LIKE STORMS WILL SPREAD ACROSS WRN AND CENTRAL INDIANA BETWEEN
2PM EST AND 7PM EST. EXPECT TORNADOES...LARGE HAIL AND DAMAGING
WINDS TO ACCOMPANY THESE STORMS.
&&
.SYNOPSIS...
ISSUED AT 355 AM EST SUN NOV 17 2013
SEVERE WEATHER IS EXPECTED TODAY WITH MUCH OF CENTRAL
INDIANA BEING IN A HIGH RISK FOR SEVERE WEATHER AS A DYNAMIC AND
STRENGTHENING LOW PRESSURE SYSTEM SWINGS OUT OF THE PLAINS AND
THROUGH THE GREAT LAKES. BY TONIGHT THE COLD FRONT ASSOCIATED WITH
THIS SYSTEM SHOULD BE THROUGH THE AREA AND DRY AIR WILL USHER IN
BEHIND IT. HIGH PRESSURE WILL BUILD IN AND BRING DRY WEATHER THROUGH
MID WEEK. A RAINY PATTERN WILL RETURN FOR THE END OF THE WEEK AND A
COLD FRONT WILL BRING COLD TEMPERATURES IN FOR NEXT WEEKEND.
&&
.NEAR TERM /UPDATE FOR TODAY/...
ISSUED AT 927 AM EST SUN NOV 17 2013
NO SIGNIFICANT CHANGES MADE TO FORECASTS. GUSTS HAVE BEGUN.
INTERMITTENT SUNSHINE WILL ADD TO INSTABILITY. STORM PREDICTION
CENTER HAD EXPANDED HIGH RISK TO NEARLY ALL OF INDIANA BUT NO REAL
CHANGE FOR CENTRAL INDIANA OTHER THAN ADDING EASTERN COUNTIES.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 355 AM EST SUN NOV 17 2013
MODELS SHOW THE COLD FRONT BEING EAST AND SOUTH OF THE FORECAST AREA
BY 0Z TONIGHT...BUT HAVE HELD ONTO POPS IN THE FAR EAST AND SOUTH
FOR THE FIRST FEW HOURS FOR COLLABORATION PURPOSES. BY 3Z HOWEVER
HAVE GONE DRY. AFTER THAT HIGH PRESSURE BUILDS IN FOR THE REMAINDER
OF THE SHORT TERM AND SHOULD SEE MOSTLY CLEAR SKIES AND SLIGHTLY
BELOW NORMAL TEMPERATURES.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 147 AM EST SUN NOV 17 2013
ECMWF AND GFS SHOW DRY WEATHER PERSISTING ACROSS CENTRAL INDIANA
ON WEDNESDAY AS HIGH PRESSURE DEPARTS THE AREA. HOWEVER A WET AND
ACTIVE END TO THE NEXT WORK WEEK LOOKS IN STORE AS SEVERAL WEATHER
SYSTEMS LOOKS TO PUSH ACROSS THE REGION STARTING ON THURSDAY AND
CONTINUING THROUGH SATURDAY. SEVERAL UPPER LEVEL WEATHER SYSTEMS
WITH A MOIST SOUTHWEST FLOW IN PLACE ALOFT WILL PROVIDE SEVERAL
CHANCES AT SHOWERS STARTING ON THURSDAY AND AGAIN ON FRIDAY AS A
WARM FRONTAL BOUNDARY PASSES ACROSS THE OHIO VALLEY.
THE GFS AND ECMWF SHOW A STRONGER COLD FRONT PUSHING ACROSS THE
REGION ON FRIDAY NIGHT...GIVING US ANOTHER SHOT AT PRECIP...ALONG
WITH MUCH COLDER AIR IN THE WAKE OF THE FRONT FOR NEXT WEEKEND.
&&
.AVIATION /DISCUSSION FOR THE 171800Z TAF ISSUANCE/...
ISSUED AT 1127 AM EST SUN NOV 17 2013
STRONG LOW PRESSURE SYSTEM WAS SPAWNING SUPERCELL THUNDERSTORMS
ACROSS ILLINOIS AND MISSOURI LATE THIS MORNING. ADDITIONAL AFTERNOON
SUPERCELL DEVELOPMENT IS EXPECTED ACROSS CENTRAL INDIANA THIS
AFTERNOON FOLLOWED BY A LINE OF SEVERE STORMS. THE BEST TIMING FOR
THE LINE...WHICH WILL BE JUST AHEAD OF THE FRONT...WILL BE IN THE
LAF AND HUF AREAS AROUND 19Z-21Z AND IND AND BMG AROUND 20-22Z.
CONFIDENCE IS GOOD REGARDING THE TIMING OF THIS SQUALL LINE.
SO...WILL START WITH VCTS AND THEN GO WITH TEMPO THUNDERSTORMS FOR 2
HOURS WITH SEVERE GUSTS TO 50 KNOTS FROM THE SOUTHWEST AS STORM
MOITON IS EXPECTED TO BE SOUTHWEST AT 50 KNOTS OR MORE. SOUTH AND
SOUTHWEST GRADIENT WINDS ALONE SHOULD GUST TO 35 KNOTS OR MORE WITH
SUSTAINED WINDS NEAR 25 KNOTS. MVFR AND POSSIBLY IFR CONDITIONS IN
STORMS WILL IMPROVE TO VFR AS THE FRONT MOVES THROUGH WITH CLEARING
LATE IN THE EVENING. SHOULD ONLY SCATTERED DIURNAL CU TOMORROW AFTER
16Z.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 9 PM EST THIS EVENING FOR INZ021-028>031-
035>049-051>057-060>065-067>072.
&&
$$
MESO UPDATE...DWM
SYNOPSIS...CP
NEAR TERM...TUCEK
SHORT TERM...CP
LONG TERM....PUMA
AVIATION...MK
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS WICHITA KS
1242 PM CST SUN NOV 17 2013
.UPDATE...
ISSUED AT 1226 PM CST SUN NOV 17 2013
HOISTED HIGH WIND WARNING ACROSS NORTHERN PORTION OF CWA. SURFACE
OBSERVATIONS UPSTREAM CONTINUING TO DETECT WIND GUSTS FLIRTING OR
EXCEEDING 50KTS. BOTH HRRR AND RUC DEPICTING NARROW CORRIDOR OF
50KT OR GREATER WINDS AFFECTING RUSSELL AND LINCOLN
COUNTIES...WITH 0.5 PV FOLD TRAVERSING THE REGION BETWEEN
18-21UTC...WHICH SHOULD ENHANCE MOMENTUM TRANSPORT. HWW THREAT
WILL BE ON THE LOW END ACROSS ELLSWORTH AND SALINE
COUNTIES...HOWEVER GIVEN I-70 RUNS THROUGH THESE AREAS...FELT
INCLUDING THEM WOULD BE PRUDENT GIVEN POTENTIAL IMPACT TO TRAFFIC.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 257 AM CST SUN NOV 17 2013
CURRENT SATELLITE WATER VAPOR IMAGERY SHOWS A VIGOROUS UPPER WAVE
OVER COLORADO WHICH WILL SWEEP EASTWARD ACROSS THE CENTRAL PLAINS
TODAY. DEEP ADIABATIC MIXING/STRONG DOWNWARD MOMENTUM TRANSFER
BEHIND THE COLD FRONT WILL CAUSE VERY STRONG NORTHWEST WINDS TO
SPREAD ACROSS MUCH OF THE AREA TODAY...THUS WILL EXPAND THE WIND
ADVISORY INTO SOUTHEAST KANSAS FOR THIS AFTERNOON. ITS POSSIBLE THAT
SOME LOCATIONS IN CENTRAL KANSAS AROUND I-70 CORRIDOR COULD GET
VERY CLOSE TO HIGH WIND WARNING LEVELS. OTHERWISE THE WINDS SHOULD
DIMINISH RAPIDLY AROUND SUNSET AS THE BOUNDARY LAYER COOLS AND
STABILIZES. SURFACE HIGH PRESSURE WILL BUILD OVER THE REGION ON
MONDAY THEN SLIDE EAST OF KANSAS ON TUESDAY...WITH NEAR NORMAL
TEMPERATURES AND DRY WEATHER EXPECTED.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 257 AM CST SUN NOV 17 2013
THE MODEL DIFFERENCES CONTINUE BETWEEN THE GFS/ECMWF MODELS ON THE
HANDLING/TIMING OF THE COLD AIR AND RESULTANT AFFECTS ON
PRECIPITATION TYPE FOR THURSDAY INTO SATURDAY...HOWEVER THE
SYNOPTIC PATTERN BY BOTH MODELS STILL SUGGESTS THAT THE COLD DENSE
AIR COULD WIN OUT AND SURGE SOUTHWARD FOR LATE NEXT WEEK. WE WILL
TREND TEMPERATURES DOWN AND CHANGE PRECIP TYPE OVER TO WINTER
TYPE PRECIP SOONER. DEFINITELY A PERIOD TO KEEP AN EYE ON WITH
LATER FORECAST UPDATES...SINCE ACCUMULATING SNOW COULD MATERIALIZE
FOR KANSAS.
JAKUB
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1226 PM CST SUN NOV 17 2013
WIND WILL BE THE MAIN AVIATION IMPACT THIS AFTERNOON. DEEP MIXING
WILL RESULT IN SUSTAINED WINDS IN THE 30-35KT RANGE WITH GUSTS
35-45KTS AT KICT...KHUT AND KCNU DURING THE AFTERNOON. STRONGER
WINDS EXPECTED AT KRSL AND KSLN...WHERE SUSTAINED WINDS WILL
AVERAGE 40KTS WITH GUSTS 50KTS. WINDS WILL SUBSIDE AROUND SUNSET
AS MIXING DIMINISHES.
VFR SKIES AND VISIBILITY EXPECTED THROUGHOUT THE TAF PERIOD.
SF
&&
.FIRE WEATHER...
ISSUED AT 257 AM CST SUN NOV 17 2013
THE COMBINATION OF VERY STRONG NORTHWEST WINDS AND MUCH DRIER AIR
SPREADING SOUTHWARD WILL CREATE CRITICAL GRASSLAND FIRE DANGER
LEVELS ACROSS CENTRAL KANSAS...AND A GOOD PORTION OF SOUTH CENTRAL
KANSAS TODAY. A RED FLAG WARNING REMAINS IN EFFECT FOR TODAY AND
IF ANY FIRES WERE TO DEVELOP THEY WOULD BECOME NEARLY IMPOSSIBLE
TO CONTROL.
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 31 58 34 60 / 0 0 0 0
HUTCHINSON 29 58 33 60 / 0 0 0 0
NEWTON 30 57 34 60 / 0 0 0 0
ELDORADO 32 58 34 59 / 0 0 0 0
WINFIELD-KWLD 32 59 35 61 / 0 0 0 0
RUSSELL 25 58 33 60 / 0 0 0 0
GREAT BEND 26 58 33 61 / 0 0 0 0
SALINA 28 58 33 60 / 0 0 0 0
MCPHERSON 29 58 33 60 / 0 0 0 0
COFFEYVILLE 34 59 34 61 / 0 0 0 10
CHANUTE 33 58 33 59 / 0 0 0 10
IOLA 33 57 33 59 / 0 0 0 10
PARSONS-KPPF 33 58 33 60 / 0 0 0 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR KSZ032-033-
047>053-067>069-082-083.
WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR KSZ047-050>053-
067>072-082-083-094>096.
HIGH WIND WARNING UNTIL 3 PM CST THIS AFTERNOON FOR KSZ032-033-
048-049.
WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR KSZ032-033-048-049.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1215 PM CST Sun Nov 17 2013
.UPDATE...
Issued at 1151 AM CST SUN NOV 17 2013
The latest runs of the RAP and HRRR have been highlighting the
potential for wind gusts around 50 kt for areas south and west of
a line from Concordia to Topeka to Emporia. The forecast soundings
show strong sinking motion in the low levels which may enhance the
downward momentum transfer of winds to the surface. The low level
jet is forecast to increase through the early afternoon hours
directly over the area. There has already been gusts up to 53 mph
in north central KS. These wind gusts will likely begin now around
central KS and work eastward into east central KS during the early
afternoon hours. Therefore have upgraded the wind advisory to a
high wind warning. There is also the possibility that the red
flag warning may need to be expanded eastward very soon given this
deeper mixing in the boundary layer resulting in lower dew points.
&&
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 335 AM CST SUN NOV 17 2013
Latest surface analysis at 08Z had a surface low over north central
Kansas along a stationary front that extended from Iowa back into
southeast Colorado. Satellite imagery this morning shows the
shortwave trough moving out of the Rockies.
The surface low pressure is forecast to move off to the east as the
upper wave moves through the Central Plains with an increasing
pressure gradient behind the cold front moving across northeast
Kansas. This will bring strong winds of 25 to 30 mph with gusts to
around 45 mph possible from mid morning through late afternoon as
forecast soundings show deep mixing today with steep low level lapse
rates. These stronger winds will affect the entire forecast area and
sustained winds around 30 mph will be common so will go with a wind
advisory today from 10 am to 5 pm. The deep mixing will also mix
down drier air and as a result minimum afternoon humidity of 20
percent or less is expected across parts of north central Kansas.
The low relative humidity and critical fuels will produce very high
to extreme fire danger and will continue with the Red Flag Warning
for parts of north central Kansas today.
Tonight the winds will be on the decrease through the early evening
hours as the lower boundary layer decouples and broad surface high
pressure builds into central and eastern Kansas. Lows tonight will
fall into the middle 20s in north central to the mid 30s in east
central Kansas.
.LONG TERM...(Monday through Saturday)
Issued at 335 AM CST SUN NOV 17 2013
Early week periods starting fairly quiet, but southerly winds under
zonal flow aloft will bring moisture back rather quickly. Models are
trending faster with a shortwave zipping though the flow, with
moderate upper level potential vorticity advection and mid-level
isentropic lift combining for elevated precipitation possibilities
as early as Tuesday evening. Increasing lapse rates and PW values
again well above normal support some mention of thunder as well.
The faster timing should keep mixing up for a warmer night as well
as a quicker drying trend for Wednesday.
The medium range models are in agreement with increasingly amplified
split flow setting up for the late week periods, but much is left be
desired in agreement in the details and a low confidence forecast
continues. One issue is how fast the cold air will surge in behind a
northern branch wave and another is the character and speed of
southern branch upper energy. At this point have the highest PoPs
Thursday night and Friday with temps steadily cooling with column
temps increasingly supporting snow inclusion with time. There is
decent agreement with a secondary cold surge pushing precip chances
to the south by the weekend.
&&
.AVIATION...(For the 18Z TAFs through 18Z Monday Afternoon)
Issued at 1151 AM CST SUN NOV 17 2013
Have increased the wind speeds at all the taf sites due to the
latest guidance suggesting higher winds moving across the area
early this afternoon. The winds should diminish in the late
afternoon and early evening especially after sunset.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY until 5 PM CST this afternoon FOR KSZ008>012-024-
026-040-056-058-059.
HIGH WIND WARNING until 3 PM CST this afternoon FOR KSZ020>023-
034>039-054-055.
RED FLAG WARNING until 6 PM CST this evening FOR KSZ008-020>022-
034>037.
&&
$$
UPDATE...Sanders
SHORT TERM...53
LONG TERM...65
AVIATION...Sanders
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1246 PM EST SUN NOV 17 2013
LATEST UPDATE...
MESOSCALE DISCUSSION
.MESOSCALE DISCUSSION...
ISSUED AT 1245 PM EST SUN NOV 17 2013
SIGNIFICANT LINE OF SEVERE STORMS HAS ALREADY EVOLVED FROM SRN
WISCONSIN SOUTHWARD ACROSS ILLINOIS. ALL OF THIS ACTIVITY WILL BE
MOVING RAPIDLY INTO SRN LWR MI OVER THE NEXT FEW HOURS AT A VERY
HIGH RATE OF SPEED NEAR 60 MPH AND SHOULD CONGEAL INTO MORE OF A
SOLID SQUALL LINE.
SFC BASED INSTABILITY HAS NOT YET DEVELOPED IN SW LWR MI AND THE
CURRENT ACTIVITY IS IN AN AREA OF 1500 J/KG OF SFC BASED CAPE.
LATEST RAP13 GUIDANCE KEEPS OUR SFC BASED CAPES UNDER 500 J/KG
THROUGH 22Z THEN JUMPS ABOVE 500 J/KG AFTER 22Z. ALTHOUGH THE
INSTABILITY IN SW LWR MI WILL LIKELY BE LESS THAN UPSTREAM AS THIS
EVENT UNFOLDS... THE VERY STRONG SHEAR/DYNAMICS WILL PROBABLY
COMPENSATE WITH A SIGNIFICANT WIND THREAT STILL LIKELY.
THE SERIOUS TORNADO THREAT HAS BEEN HIGHLIGHTED IN ALL OF THE SPC
UPDATES AND STATEMENTS AND SEVERAL TORNADO WARNINGS ARE CURRENTLY
IN EFFECT UPSTREAM ACROSS ILLINOIS.
BOTTOM LINE... A SIGNIFICANT SEVERE WEATHER OUTBREAK IS GOING TO
HAPPEN SOON IN SW LWR MI... AND THE EVENT WILL PROGRESS VERY
QUICKLY.
&&
.SYNOPSIS...
ISSUED AT 326 AM EST SUN NOV 17 2013
PEOPLE IN SOUTHWEST LOWER MICHIGAN SHOULD PAY ATTENTION TO THE
WEATHER TODAY BECAUSE IT LOOKS LIKE WE/RE GOING TO SEE A SIGNIFICANT
WIND EVENT. A HIGH WIND WARNING IS IN EFFECT FOR ALL OF SOUTHWEST
LOWER MICHIGAN FROM 4 PM THIS AFTERNOON THROUGH 4 AM MONDAY.
A STRONG AUTUMN STORM WILL STRENGTHEN AS IT MOVES FROM IOWA
TOWARD THE LEELANAU PENINSULA. SHOWERS AND THUNDERSTORMS WILL
CONTINUE TO DEVELOP TODAY AS A WARM FRONT MOVES NORTH. HOWEVER
THIS AFTERNOON...STORMS WILL LIKELY BECOME STRONG TO SEVERE AS
VERY STRONG DYNAMICS TAP INTO A MOISTURE RICH AIRMASS AHEAD OF THE
APPROACHING COLD FRONT. WIND GUSTS IN EXCESS OF 60 MPH ARE
POSSIBLE THIS AFTERNOON ALONG WITH ISOLATED TORNADOES. THE STORM
PREDICTION CENTER MAINTAINS A MODERATE RISK OF SEVERE STORMS
ACROSS CENTRAL LOWER MICHIGAN TODAY WITH A HIGH RISK REACHING INTO
SOUTHERN LOWER MICHIGAN.
MIXED RAIN/SNOW SHOWERS ARE EXPECTED MONDAY AS HIGHS FALL BACK TO
THE LOWER 40S.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 326 AM EST SUN NOV 17 2013
LATEST MODEL RUNS DIDN/T CHANGE THE THINKING THAT WE/RE STARING AT A
SIGNIFICANT WIND THREAT TODAY. STRONG TO SEVERE STORMS ARE POSSIBLE
ESPECIALLY THIS AFTERNOON FOLLOWED BY STRONG GRADIENT WINDS BEHIND
THE COLD FRONT LATE AFTERNOON AND EVENING. AS A RESULT WE ISSUED A
HIGH WIND WARNING THAT/S IN EFFECT FROM 4 PM TODAY THROUGH 4 AM
MONDAY.
A NEGATIVELY TILTED TROUGH WILL APPROACH THE GREAT LAKES. SFC LOW
PRESSURE IN THE MISSOURI VALLEY WILL MOVE TOWARD THE LEELANAU
PENINSULA LATE TODAY. A WARM FRONT LIFTING NORTH WILL BE AN INITIAL
FOCUS FOR CONVECTION. HOWEVER THE MAIN SHOW WILL BE THIS AFTERNOON
AHEAD OF THE COLD FRONT. A LOW LEVEL JET NEAR 65 KNOTS COUPLED WITH
A MID LEVEL JET NEAR 95 KNOTS WILL GENERATE SIGNIFICANT SHEAR THIS
AFTERNOON. IN ADDITION THE LEFT EXIT REGION OF THE UPPER JET WILL
MOVE OVER THE CWA LATE THIS AFTERNOON. IF WE CAN REALIZE CLOSE TO
THE 800 J/KG MLCAPE THE MODELS INDICATE WE SHOULD HAVE MORE THAN
ENOUGH FORCING AND ORGANIZATION FOR SUPERCELLS TO DEVELOP AHEAD OF
THE COLD FRONT. THE STRONG SHORT WAVE MOVING IN AT THE SAME TIME
WILL ONLY AID IN THE LIFT.
SPC MAINTAINS A MODERATE RISK FOR SEVERE STORMS WITH A HIGH RISK
JUST SOUTH OF THE CWA. CAN/T ARGUE WITH THAT. THE HRRR SHOWS A
BROKEN LINE OF STORMS ARRIVING AT THE SHORE AROUND 20Z. THIS
TIMING IS CONSISTENT WITH OTHER MODELS. THE MAIN SEVERE THREAT
LOOKS TO BE FROM 20Z THROUGH 01Z. AFTER THE COLD FRONT SWEEPS
THROUGH THE ATTENTION WILL TURN TO SYNOPTIC WINDS.
THE WIND THREAT WILL CONTINUE THIS EVENING. NAM SHOWS 3 HRLY
PRESSURE RISES IN THE 9-10 MB RANGE WHICH IS PRETTY HIGH AND SHOULD
RESULT IN HIGH WIND WARNING TYPE WINDS...ESPECIALLY ALONG THE COAST
WHERE GUSTS TO 55-65 MPH ARE POSSIBLE. STRONG COLD ADVECTION WILL
HELP TO PULL DOWN THE 55 KNOTS SEEN AT 900 FEET ON BUFKIT WIND
PROFILES. SURE SEEMS LIKE SCATTERED POWER OUTAGES WILL BE POSSIBLE
FROM THIS AFTERNOON THROUGH TONIGHT. WINDS WILL DIMINISH LATE
TONIGHT.
MIXED RAIN/SNOW SHOWERS POSSIBLE MONDAY/TUESDAY AS HIGHS ONLY CLIMB
INTO THE LOWER 40S.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 326 AM EST SUN NOV 17 2013
NO BIG STORMS IN THE EXTENDED. BUMPED UP MAXES A BIT ON WEDNESDAY AS
EURO HAS 850 MB TEMPS AROUND 5C WHICH LOOKS REASONABLE GIVEN DEEP
SOUTHERLY FLOW. ENOUGH MOISTURE MAY BE DRAWN NORTHWARD TO BRING SOME
SHOWERS BY WEDNESDAY NIGHT INTO THURSDAY AS IT POOLS IN FRONT OF
ADVANCING COLD FRONT.
COLDER AIR FILTERS IN FOR THURSDAY NIGHT AND FRIDAY WITH PRECIP
TRANSITIONING TO SNOW BY FRIDAY NIGHT. FORECAST CONFIDENCE IN THE
DETAILS IS LOW WITH POOR RUN TO RUN CONSISTENCY FOR FRIDAY AND
SATURDAY. THE GFS HAS A SFC LOW AND SECONDARY COLD FRONT COMING
THROUGH FRIDAY WHILE THE EURO IS FURTHER NORTH AND SLOWER WITH THE
LOW. SHOULD BE COLD ENOUGH FOR ALL SNOW BY FRIDAY NIGHT AND SATURDAY
IN EITHER SCENARIO.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY)
ISSUED AT 1200 PM EST SUN NOV 17 2013
WIDESPREAD MVFR/IFR CONDITIONS WILL CONTINUE THIS AFTERNOON. SEVERE
THUNDERSTORMS ARE EXPECTED THIS AFTERNOON WITH HIGH WIND GUSTS ALONG
WITH POTENTIAL FOR HAIL AND EVEN A FEW TORNADOES. ONCE THIS MOVES
THROUGH...HIGH WIND THREAT CONTINUES WITH WIDESPREAD GUSTS OVER 40
MPH AND AS HIGH AS 60 MPH DURING THE EVENING. WINDS WILL START OUT
SOUTH EARLY THIS AFTERNOON...GO SOUTHWEST LATER THIS AFTERNOON AND
THEN WEST LATER TONIGHT.
&&
.MARINE...
ISSUED AT 326 AM EST SUN NOV 17 2013
UPGRADED THE GALE WARNING TO A STORM WARNING. IN ADDITION TO STRONG
TO SEVERE THUNDERSTORMS TODAY STRONG GRADIENT WINDS WILL DEVELOP
BEHIND A COLD FRONT LATE THIS AFTERNOON. WEST STORM FORCE WINDS TO
55 KNOTS ARE EXPECTED THROUGH THE EARLY OVERNIGHT HOURS BEFORE
DECREASING TO 40 KNOT GALES. WAVES WILL BUILD TO 10 TO 15 FEET
TONIGHT.
&&
.HYDROLOGY...
ISSUED AT 326 AM EST SUN NOV 17 2013
HEAVY RAINFALL POSSIBLE IN STORMS TODAY...ESPECIALLY THIS AFTERNOON.
LOOK FOR ADDITIONAL RAINFALL ACCUMULATIONS AROUND AN INCH THROUGH
EARLY EVENING. THIS LIKELY WON`T CAUSE RIVER FLOODING. HOWEVER
LOCALIZED FLOODING MAY DEVELOP IN POOR DRAINAGE AREAS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...HIGH WIND WARNING FROM 4 PM THIS AFTERNOON TO 4 AM EST MONDAY
FOR MIZ037>040-043>046-050>052-056>059-064>067-071>074.
LM...STORM WARNING UNTIL 4 AM EST MONDAY FOR LMZ844>849.
&&
$$
MESOSCALE...MEADE
SYNOPSIS...93
SHORT TERM...93
LONG TERM...OSTUNO
AVIATION...LAURENS
HYDROLOGY...93
MARINE...93
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1200 PM EST SUN NOV 17 2013
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 326 AM EST SUN NOV 17 2013
PEOPLE IN SOUTHWEST LOWER MICHIGAN SHOULD PAY ATTENTION TO THE
WEATHER TODAY BECAUSE IT LOOKS LIKE WE/RE GOING TO SEE A SIGNIFICANT
WIND EVENT. A HIGH WIND WARNING IS IN EFFECT FOR ALL OF SOUTHWEST
LOWER MICHIGAN FROM 4 PM THIS AFTERNOON THROUGH 4 AM MONDAY.
A STRONG AUTUMN STORM WILL STRENGTHEN AS IT MOVES FROM IOWA
TOWARD THE LEELANAU PENINSULA. SHOWERS AND THUNDERSTORMS WILL
CONTINUE TO DEVELOP TODAY AS A WARM FRONT MOVES NORTH. HOWEVER
THIS AFTERNOON...STORMS WILL LIKELY BECOME STRONG TO SEVERE AS
VERY STRONG DYNAMICS TAP INTO A MOISTURE RICH AIRMASS AHEAD OF THE
APPROACHING COLD FRONT. WIND GUSTS IN EXCESS OF 60 MPH ARE
POSSIBLE THIS AFTERNOON ALONG WITH ISOLATED TORNADOES. THE STORM
PREDICTION CENTER MAINTAINS A MODERATE RISK OF SEVERE STORMS
ACROSS CENTRAL LOWER MICHIGAN TODAY WITH A HIGH RISK REACHING INTO
SOUTHERN LOWER MICHIGAN.
MIXED RAIN/SNOW SHOWERS ARE EXPECTED MONDAY AS HIGHS FALL BACK TO
THE LOWER 40S.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 326 AM EST SUN NOV 17 2013
LATEST MODEL RUNS DIDN/T CHANGE THE THINKING THAT WE/RE STARING AT A
SIGNIFICANT WIND THREAT TODAY. STRONG TO SEVERE STORMS ARE POSSIBLE
ESPECIALLY THIS AFTERNOON FOLLOWED BY STRONG GRADIENT WINDS BEHIND
THE COLD FRONT LATE AFTERNOON AND EVENING. AS A RESULT WE ISSUED A
HIGH WIND WARNING THAT/S IN EFFECT FROM 4 PM TODAY THROUGH 4 AM
MONDAY.
A NEGATIVELY TILTED TROUGH WILL APPROACH THE GREAT LAKES. SFC LOW
PRESSURE IN THE MISSOURI VALLEY WILL MOVE TOWARD THE LEELANAU
PENINSULA LATE TODAY. A WARM FRONT LIFTING NORTH WILL BE AN INITIAL
FOCUS FOR CONVECTION. HOWEVER THE MAIN SHOW WILL BE THIS AFTERNOON
AHEAD OF THE COLD FRONT. A LOW LEVEL JET NEAR 65 KNOTS COUPLED WITH
A MID LEVEL JET NEAR 95 KNOTS WILL GENERATE SIGNIFICANT SHEAR THIS
AFTERNOON. IN ADDITION THE LEFT EXIT REGION OF THE UPPER JET WILL
MOVE OVER THE CWA LATE THIS AFTERNOON. IF WE CAN REALIZE CLOSE TO
THE 800 J/KG MLCAPE THE MODELS INDICATE WE SHOULD HAVE MORE THAN
ENOUGH FORCING AND ORGANIZATION FOR SUPERCELLS TO DEVELOP AHEAD OF
THE COLD FRONT. THE STRONG SHORT WAVE MOVING IN AT THE SAME TIME
WILL ONLY AID IN THE LIFT.
SPC MAINTAINS A MODERATE RISK FOR SEVERE STORMS WITH A HIGH RISK
JUST SOUTH OF THE CWA. CAN/T ARGUE WITH THAT. THE HRRR SHOWS A
BROKEN LINE OF STORMS ARRIVING AT THE SHORE AROUND 20Z. THIS
TIMING IS CONSISTENT WITH OTHER MODELS. THE MAIN SEVERE THREAT
LOOKS TO BE FROM 20Z THROUGH 01Z. AFTER THE COLD FRONT SWEEPS
THROUGH THE ATTENTION WILL TURN TO SYNOPTIC WINDS.
THE WIND THREAT WILL CONTINUE THIS EVENING. NAM SHOWS 3 HRLY
PRESSURE RISES IN THE 9-10 MB RANGE WHICH IS PRETTY HIGH AND SHOULD
RESULT IN HIGH WIND WARNING TYPE WINDS...ESPECIALLY ALONG THE COAST
WHERE GUSTS TO 55-65 MPH ARE POSSIBLE. STRONG COLD ADVECTION WILL
HELP TO PULL DOWN THE 55 KNOTS SEEN AT 900 FEET ON BUFKIT WIND
PROFILES. SURE SEEMS LIKE SCATTERED POWER OUTAGES WILL BE POSSIBLE
FROM THIS AFTERNOON THROUGH TONIGHT. WINDS WILL DIMINISH LATE
TONIGHT.
MIXED RAIN/SNOW SHOWERS POSSIBLE MONDAY/TUESDAY AS HIGHS ONLY CLIMB
INTO THE LOWER 40S.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 326 AM EST SUN NOV 17 2013
NO BIG STORMS IN THE EXTENDED. BUMPED UP MAXES A BIT ON WEDNESDAY AS
EURO HAS 850 MB TEMPS AROUND 5C WHICH LOOKS REASONABLE GIVEN DEEP
SOUTHERLY FLOW. ENOUGH MOISTURE MAY BE DRAWN NORTHWARD TO BRING SOME
SHOWERS BY WEDNESDAY NIGHT INTO THURSDAY AS IT POOLS IN FRONT OF
ADVANCING COLD FRONT.
COLDER AIR FILTERS IN FOR THURSDAY NIGHT AND FRIDAY WITH PRECIP
TRANSITIONING TO SNOW BY FRIDAY NIGHT. FORECAST CONFIDENCE IN THE
DETAILS IS LOW WITH POOR RUN TO RUN CONSISTENCY FOR FRIDAY AND
SATURDAY. THE GFS HAS A SFC LOW AND SECONDARY COLD FRONT COMING
THROUGH FRIDAY WHILE THE EURO IS FURTHER NORTH AND SLOWER WITH THE
LOW. SHOULD BE COLD ENOUGH FOR ALL SNOW BY FRIDAY NIGHT AND SATURDAY
IN EITHER SCENARIO.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY)
ISSUED AT 1200 PM EST SUN NOV 17 2013
WIDESPREAD MVFR/IFR CONDITIONS WILL CONTINUE THIS AFTERNOON. SEVERE
THUNDERSTORMS ARE EXPECTED THIS AFTERNOON WITH HIGH WIND GUSTS ALONG
WITH POTENTIAL FOR HAIL AND EVEN A FEW TORNADOES. ONCE THIS MOVES
THROUGH...HIGH WIND THREAT CONTINUES WITH WIDESPREAD GUSTS OVER 40
MPH AND AS HIGH AS 60 MPH DURING THE EVENING. WINDS WILL START OUT
SOUTH EARLY THIS AFTERNOON...GO SOUTHWEST LATER THIS AFTERNOON AND
THEN WEST LATER TONIGHT.
&&
.MARINE...
ISSUED AT 326 AM EST SUN NOV 17 2013
UPGRADED THE GALE WARNING TO A STORM WARNING. IN ADDITION TO STRONG
TO SEVERE THUNDERSTORMS TODAY STRONG GRADIENT WINDS WILL DEVELOP
BEHIND A COLD FRONT LATE THIS AFTERNOON. WEST STORM FORCE WINDS TO
55 KNOTS ARE EXPECTED THROUGH THE EARLY OVERNIGHT HOURS BEFORE
DECREASING TO 40 KNOT GALES. WAVES WILL BUILD TO 10 TO 15 FEET
TONIGHT.
&&
.HYDROLOGY...
ISSUED AT 326 AM EST SUN NOV 17 2013
HEAVY RAINFALL POSSIBLE IN STORMS TODAY...ESPECIALLY THIS AFTERNOON.
LOOK FOR ADDITIONAL RAINFALL ACCUMULATIONS AROUND AN INCH THROUGH
EARLY EVENING. THIS LIKELY WON`T CAUSE RIVER FLOODING. HOWEVER
LOCALIZED FLOODING MAY DEVELOP IN POOR DRAINAGE AREAS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...HIGH WIND WARNING FROM 4 PM THIS AFTERNOON TO 4 AM EST MONDAY
FOR MIZ037>040-043>046-050>052-056>059-064>067-071>074.
LM...STORM WARNING FROM 4 PM THIS AFTERNOON TO 4 AM EST MONDAY FOR
LMZ844>849.
GALE WARNING UNTIL 4 PM EST THIS AFTERNOON FOR LMZ844>849.
&&
$$
SYNOPSIS...93
SHORT TERM...93
LONG TERM...OSTUNO
AVIATION...LAURENS
HYDROLOGY...93
MARINE...93
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1234 PM CST SUN NOV 17 2013
.UPDATE...
ISSUED AT 1233 PM CST SUN NOV 17 2013
WINDS HAVE STARTED TO INCREASE MORE THAN EXPECTED ESPECIALLY IN
NORTH CENTRAL KANSAS. THE LATEST HRRR INDICATES THE STRONGEST
WINDS WILL BE EARLY THIS AFTERNOON IN NORTH CENTRAL KANSAS. HAVE
ISSUED A HIGH WIND WARNING FOR THIS AREA. WINDS CONTINUE TO BE
GUSTY ACROSS THE REMAINDER OF THE AREA AND WILL CONTINUE THE WIND
ADVISORY FOR NEBRASKA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 307 AM CST SUN NOV 17 2013
FOCUS IS ON A PERIOD OF INTENSE WINDS TODAY AND CRITICAL FIRE
WEATHER CONDITIONS.
SPRINKLES OR A BANDED AREA OF VERY LIGHT RAIN DEVELOPED DURING
THE PRE DAWN HOURS IN PRESENCE OF MID LEVEL FRONTOGENESIS AND
DYNAMICS AS A LEAD SHORTWAVE TROUGH CROSSES NEB AND A COLD FRONTAL
BOUNDARY WORKS EAST/SOUTHEAST. LIFT IS FOCUSED MAINLY NORTH OF
INTERSTATE 80 AND MAY LINGER JUST BEYOND 12Z IN OUR EASTERN ZONES.
SFC COLD FRONT WILL CLEAR OUR CWA BY DAYBREAK WITH A STRONGER
SHORTWAVE TROUGH CROSSING THE NORTHERN/CENTRAL PLAINS MID/LATE
MORNING WITH A SECONDARY COLD FRONT AND COOLER AIR MAKING A PUSH
SOUTHEASTWARD BY MIDDAY...AND THE MID LEVEL THERMAL TROUGH SWEEPS
SOUTHEAST TOWARD THE MISSOURI RIVER BY LATE AFTN. 3HR PRESSURE
RISES BEHIND THE INITIAL FRONT BY DAYBREAK AVERAGE NEAR 7MB ACROSS
PORTIONS OF CENTRAL/EASTERN KANSAS...THEN AVERAGE 4 TO 6MB ACROSS
CENTRAL/EASTERN NEB BEHIND SECONDARY BOUNDARY THIS AFTN. IN A TIGHT
PRESSURE GRADIENT BEHIND THE BOUNDARIES...AN INTENSE PERIOD OF
NORTHWEST WINDS ARE EXPECTED BEGINNING AROUND MID
MORNING...PEAKING AROUND MID DAY OR EARLY AFTERNOON...THEN
SUBSIDING IN THE EVENING AS THE SYSTEM DEPARTS AND GRADIENT
RELAXES. MODEL FORECAST SOUNDINGS SUGGEST THE DEEPEST MIXING WILL
OCCUR ACROSS OUR SOUTHERN/SOUTHWEST ZONES WHERE MIXING WILL REACH
JUST ABOVE H8. WINDS AT THE TOP OF THE LAYER ARE NEAR 50KTS IN NC
KANSAS AROUND MID DAY THEN DECREASE THE AROUND 35KTS BY MID/LATE
AFTN. FARTHER NORTH ACROSS OUR NORTHERN ZONES MIXING IS BETWEEN H8
AND H85 WITH WINDS AT THE TOP OF THE LAYER AVERAGING 35 TO 40KTS.
IN ANY CASE...VERY WINDY CONDITIONS WILL DEVELOP TODAY AND CURRENT
WIND ADVISORY HEADLINE REMAINS ON TRACK. HAVE SOME CONCERNS THAT
PORTIONS OF NC KANSAS TOWARDS THE RUSSEL AREA MAY NEAR OR REACH
HIGH WIND WARNING CRITERIA AND THIS WILL NEED TO BE MONITORED
CLOSELY.
SHORT TERM MODELS INDICATE THE PRESENCE OF MID LEVEL MOISTURE ACROSS
OUR NORTHEAST ZONES TODAY AND PLACE CONVECTIVE TEMPS IN THE UPPER
40S TO AROUND 50F...WHICH ARE AROUND FORECAST HIGHS FOR TODAY.
CONFIDENCE IS NOT HIGH ON THE DEGREE OF CLOUD COVER IN THIS
AREA...BUT DID GO WITH AT LEAST PARTLY CLOUDY CONDITIONS. AS FAR
AS TEMPERATURES GO...WE WILL BE ON A DOWNWARD TREND COMPARED TO
THE MILD CONDITIONS ON SATURDAY WITH HIGHS TODAY AVERAGING IN THE
50S.
THE COLDER AIRMASS WILL BE MORE NOTICEABLE TONIGHT IN GOOD
RADIATIONAL CONDITIONS. A SURFACE RIDGE AXIS SETTLES ONTO THE
PLAINS AND WINDS DROP OFF...SKIES CLEAR AND VERY DRY DPS FM THE
TEENS TO LOW 20S WILL BE IN PLACE. HAVE TARGETED LOWS FROM THE
TEENS IN THE RIVER VALLEYS IN OUR WESTERN ZONES...TO THE LOW/MID
20S IN THE EAST.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 307 AM CST SUN NOV 17 2013
ALOFT: HEIGHTS WILL BE RISING MON IN THE WAKE OF THE STORM EXITING
THE REGION TODAY...WITH A BROAD LOW-AMPLITUDE RIDGE ENVELOPING THE
CNTRL USA. AS THE WEEK PROGRESSES...SPLIT FLOW WILL EVOLVE WITH GOOD
MODEL AGREEMENT ON THE NRN STREAM /ALONG THE US-CANADA BORDER/
DELIVERING ANOTHER COLD AIR MASS TO THE REGION. MEANWHILE...A TROF
WILL MOVE INTO THE DESERT SW LATE WED AND CLOSE OFF INTO A CUT-OFF
LOW AS THE WAVELENGTH SHORTENS AND HIGHER LATITUDE AMPLIFICATION
OCCURS. HEIGHTS WILL THEN BUILD DOWNSTREAM OVER THE SRN PLAINS AND
SE...RESULTING IN CONFLUENT FLOW OVER THE ERN HALF OF THE CONUS.
SURFACE: HIGH PRES WILL BE OVERHEAD AT DAWN MON. THIS HIGH WILL
DEPART INTO THE ERN USA TUE. THE FCST AREA WILL BE IN THE WARM
SECTOR OF LOW PRES ADVANCING E ALONG THE US-CANADA BORDER TUE. THE
ASSOCIATED COLD FRONT WILL SURGE S...CROSSING THE FCST AREA WED
AFTERNOON. THE CONSISTENCY OF THE PAST SEVERAL RUNS OF THE EC IS
PREFERRED AND ITS ENSEMBLE MEAN IS SUPPORTIVE. THE 00Z GEM IS ALSO
ON BOARD. THE 18Z/00Z GFS HAVE TRENDED FASTER VS 24 HRS AGO...BUT
THEY ARE STILL LAGGING. STRONG AND COLD HIGH PRES WILL SETTLE OVER
THE PLAINS THU. FRI THE HIGH WILL DEPART FOR THE GREAT LAKES AS A
CLIPPER RACES ACROSS SRN CANADA. THIS SYSTEM WILL DELIVER A
REINFORCING COLD SHOT AND HIGH PRES...BUT THE CORE OF THE COLDEST
AIR WILL HEAD INTO THE ERN USA.
THE 142 AM AND 11 AM/SAT EXTENDED FCST DISCUSSIONS FROM WPC WERE
REVIEWED FOR INCLUSION INTO THE FCST AND SUPPORT THE ABOVE SCENARIOS.
ENJOY THE FIRST FEW DAYS THIS WEEK BECAUSE THE EXTENDED FCST AND
BEYOND IS LOOKING COLD. THE WEEK WILL START WITH MILD /WARMER THAN
NORMAL/ TEMPS. THAT WILL END THU AS ARCTIC AIR SURGES S. THE EC
ENSEMBLE MEAN AND CFSV2 TEMP ANOMALIES SUGGEST TEMPS THEN AVERAGE AT
OR BELOW NORMAL TO FINISH OUT THE MONTH. THAT DOESN/T MEAN WE WON/T
HAVE A DAY HERE OR THERE OF ABOVE NORMAL WARMTH. BUT OVERALL...THE
AVERAGE SHOULD BE COLDER.
OVERALL CHANCE FOR PRECIP ARE NIL UNTIL THU NIGHT OR FRI. GFS
ENSEMBLE PROBABILITIES FOR .10" INCREASE TO 60+ PERCENT WITH A 40-50
PERCENT CHANCE OF .25" AND 15 PERCENT FOR .50". A LITTLE OVER HALF
OF THE EC ENSEMBLE MEMBERS OFFER ANYWHERE FROM .10" TO .50".
HAZARDS: FOR NOW NOTHING SPECIFIC. HOWEVER...WE CONTINUE TO SEE
HINTS OF THE CUT-OFF LOW EJECTING SHORTWAVE TROFS THAT COULD RESULT
IN A SOME LIGHT PRECIP OF THE WINTRY VARIETY IN THE THU-FRI
TIMEFRAME.
THE DAILY DETAILS...
MON: A COLD/FROSTY START. SUNNY AND TEMPS WILL REBOUND NICELY.
TUE: INCREASING MID-HIGH CLOUDS. BELIEVE WE HAVE THIS BETTER
DEPICTED VS 24 HRS AGO. BREEZY S WINDS WILL GUST TO 25-30 MPH.
WED: DRY AFTERNOON COLD FRONTAL PASSAGE. PARTLY SUNNY WITH
MULTI-LAYERED MID-HIGH CLOUDS. WINDS SHOULD BE FAIRLY LIGHT UNTIL
FRONTAL PASSAGE...THEN THEY SHOULD CRANK IT UP FROM THE N.
THU: PROBABLY CLOUDY VIA GEM/EC/GFS CROSS SECTIONS. TEMPS MAY RISE
VERY LITTLE FROM MORNING LOWS. HIGH IN THE 30S LOOK PLAUSIBLE AND
ORD-GREELEY MAY NOT REACH 30F.
FRI-SAT: UNCERTAIN. BUT CONFLUENT FLOW ALOFT WILL RESULT IN A VERY
STRONG UPPER-LEVEL JET CORE /140 KTS/ OVER THE OH VALLEY. THIS WILL
PUT US IN THE RIGHT ENTRANCE REGION. THE IMPORTANT QUESTION IS
MOISTURE AND IF IT/S FAR ENOUGH N. BOTH THE GFS AND EC HAVE IT THU
NIGHT AND THEN PUSH IT S OF THE FCST AREA FRI WITH THE POSSIBILITY
OF IMPROVING WX SAT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1122 AM CST SUN NOV 17 2013
WINDS WILL BE THE PRIMARY CONCERN THROUGH THE AFTERNOON. EXPECT
GUSTY NORTHWEST WINDS TO CONTINUE THROUGH AROUND SUNSET. WINDS
WILL GRADUALLY BECOME LIGHT DURING THE NIGHT. A FEW MID LEVEL
CLOUDS WILL MOVE THROUGH THIS AFTERNOON.
&&
.FIRE WEATHER...
ISSUED AT 307 AM CST SUN NOV 17 2013
A RED FLAG WARNING REMAINS IN EFFECT TODAY FOR ALL OF NORTH
CENTRAL KANSAS AND LOCATIONS WEST OF A LINE FROM LEXINGTON TO
FRANKLIN IN SOUTH CENTRAL NEBRASKA. INTENSE NORTHWEST WINDS ARE
FORECAST TODAY IN DEEP MIXING BEHIND A COLD FRONTAL BOUNDARY.
THE INTENSE WINDS WILL DEVELOP MID TO LATE MORNING AND REMAIN
STRONG THIS AFTN BEFORE SUBSIDING IN THE EVENING. DRY AIRMASS
ADVECTS SOUTHEAST AND LOW RELATIVE HUMIDITY VALUES WILL DROP NEAR
OR BELOW 20 PERCENT IN THE RED FLAG WARNING AREA.
THIS BEING SAID...LATEST MODEL RUNS HAVE TRENDED HIGHER WITH DPS/RH
LEVELS ACROSS PORTIONS OF SOUTH CENTRAL NEBRASKA...NAMELY
DAWSON...GOSPER AND PHELPS COUNTIES. CONDITIONS ACROSS NORTH
CENTRAL KANSAS PARTICULARLY PHILLIPS AND ROOKS COUNTIES STAND TO
SEE THE MOST CRITICAL FIRE DANGER CONDITIONS WHERE DPS IN THE
SINGLE DIGITS ARE FORECAST...RESULTING IN LOW RELATIVE HUMIDITY
VALUES AROUND 15 PERCENT. THE LOCATION OF CURRENT RED FLAG WARNING
WILL REMAIN AS IS WITH A BUFFER SURROUNDING OUR FAR SW ZONES WHERE
CONDITIONS WILL BE MOST CRITICAL. HOWEVER...IF TEMPS TREND UP AND
LOWER DPS MATERIALIZE FARTHER EAST THAN WHAT CURRENT MODELS
SHOW...THEN HEADLINE MAY NEED TO BE EXPANDED.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR NEZ039>041-046>049-
060>064-072>077-082>087.
RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR NEZ060-072-073-
082>084.
KS...RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR KSZ005>007-
017>019.
HIGH WIND WARNING UNTIL 3 PM CST THIS AFTERNOON FOR KSZ005>007-
017>019.
&&
$$
UPDATE...JCB
SHORT TERM...FAY
LONG TERM...HALBLAUB
AVIATION...JCB
FIRE WEATHER...FAY
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1238 PM EST SUN NOV 17 2013
.SYNOPSIS...
LOW PRESSURE OVER THE PLAINS STATES WILL DEEPEN RAPIDLY AS IT
MOVES NORTHEAST TODAY REACHING NORTHERN LAKE MICHIGAN BY THIS
EVENING AND INTO QUEBEC ON MONDAY. THIS WILL PUSH A STRONG COLD
FRONT ACROSS THE AREA THIS EVENING. HIGH PRESSURE WILL MOVE EAST
OUT OF THE SOUTHERN PLAINS STATES INTO THE OHIO VALLEY BY TUESDAY
AND THEN OFF THE EAST COAST ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
REMOVED THUNDER ACROSS NORTH CENTRAL OHIO AND POINTS EAST UNTIL
VERY LATE AFTERNOON/EVENING. WHILE I CANNOT RULE OUT THUNDER...
WOULD LIKE TO MAKE THE THUNDER AND WIND WITH THE FRONT MORE OF THE
FOCAL POINT OF THE FORECAST. TOUGH TO DO IN THESE DAYS OF
AUTOMATED TEXT FORMATTERS...SO NOT SURE EXACTLY WHAT THE WORDING
WILL SAY. BETTER CHANCE FOR THUNDER AT ANY TIME IN THE DRY SLOT
THAT IS CREEPING ACROSS NORTHWEST OHIO. SORT OF LOOKS LIKE
OKLAHOMA IN THE SPRING TIME...HMMM.
NO OTHER SIGNIFICANT CHANGES TO THE FORECAST. DID NUDGE UP HIGH
TEMPERATURES A COUPLE OF DEGREES ACROSS NW OHIO AND PARTS OF NORTH
CENTRAL OHIO WHERE THERE WILL NOT BE AS MANY SHOWERS. RECORD HIGH
IN TOLEDO IS 71 AND WE WILL TAKE A RUN AT IT. 72 AT CLE IS
POTENTIALLY WITHIN REACH.
RELEVANT EARLY MORNING UPDATED DISCUSSION...
SHOWERS CONTINUE TO MOVE EAST AND OUT OF THE AREA AT THIS TIME.
CELLULAR CONVECTION CONTINUES TO MOVE INTO EXTREME NORTHWEST OHIO
AND SOUTHERN LOWER MICHIGAN. THE WATER VAPOR PLUME IS ALSO PUSHING
EAST ALLOWING FOR SOME DRIER AIR TO MOVE EAST AND ALLOW FOR A
BREAK IN THE ACTION. LATEST HRRR MODEL SHOWS MASSIVE SQUALL LINE
DEVELOPING OVER ILLINOIS AND RAPIDLY INTENSIFIES AS IT MOVES EAST
TOWARD OHIO. TIMING WOULD PUT THE LINE AT TOLEDO AND FINDLAY AT
22Z AND TO CLEVELAND AND MANSFIELD BY ABOUT 00Z AND FINALLY TO
ERIE AND YOUNGSTOWN BY 02Z OR SO. SO THE WAIT BEGINS. STAY TUNED.
PREVIOUS DISCUSSION...
THE LONG ANTICIPATED SEVERE WEATHER THREAT DAY HAS ARRIVED. TWO LOW
PRESSURE SYSTEMS IN THE UPPER MIDWEST ARE BEGINNING TO MERGE AND
INTENSIFY THIS MORNING.
SOUTHERLY FLOW HAS INCREASED ACROSS THE FORECAST AREA AND THIS WILL
BE THE BEGINNING OF THE STRENGTHENING WIND FLOW THROUGHOUT THE DAY.
MODERATELY STRONG LOW LEVEL JET WILL REMAIN PERSISTENT OVER THE
FORECAST AREA TODAY AND WITH THE WARM AIR ADVECTION...SOME OF THE
STRONGER WINDS WILL MIX DOWN TO THE SURFACE. SO...WILL GO AHEAD AND
ISSUE A WIND ADVISORY FOR THE ENTIRE AREA BUT WILL BE FOR MAINLY
LATER THIS EVENING INTO TONIGHT SINCE THE STRONGEST WINDS WILL TAKE
PLACE AFTER THE COLD FRONTAL PASSAGE.
60 TO 70 KNOT SPEED MAXIMUM AT 850 MB WILL POSE A PROBLEM AS
CONVECTION DEVELOPS LATER THIS MORNING INTO THE AFTERNOON HOURS. THE
STRONGER WINDS COULD BE FORCED TO THE SURFACE IN THE THUNDERSTORMS
AND PRODUCE WIDESPREAD WIND DAMAGE. LATEST STORM PREDICTION CENTER
OUTLOOK CONTINUES TO HIGHLIGHT A MODERATE RISK FOR SEVERE
THUNDERSTORMS ACROSS THE AREA TODAY. THERE IS A HIGH RISK JUST WEST
OF THE FORECAST AREA.
EVEN THOUGH THE MAIN THREATS WILL BE THE STRONG DAMAGING
WINDS...LATEST MODEL SOUNDING HODOGRAPHS INDICATE SOME FAIRLY HIGH
LEVELS OF HELICITY...ESPECIALLY ACROSS AREAS FROM CLEVELAND TO AKRON
CANTON WEST. I CANT RULE OUT THE POTENTIAL FOR ANY THUNDERSTORMS
THAT DEVELOP THAT THEY COULD BEGIN TO ROTATE RATHER QUICKLY AND
PRODUCE TORNADOES. TEMPERATURE DEW POINT SPREADS ARE PROGGED TO BE
AT OR BELOW THE 5 DEGREE THRESHOLD AND THIS IS ONE KEY INGREDIENT
FOR TORNADOES TO DEVELOP.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
THE SEVERE WEATHER THREAT WILL NOT BE OVER TONIGHT. THE COLD FRONT
AND POTENTIAL SQUALL LINE IS EXPECTED TO MOVE THROUGH THE AREA THIS
EVENING AND THIS IS WHEN WE HAVE THE HIGHEST THREAT FOR WIDESPREAD
WIND DAMAGE. ONE FACTOR IS WE WILL BE LOSING THE DAY TIME HEATING
AND THIS MAY HELP TO STABILIZE THINGS A BIT.
AS THE COLD FRONT SHIFTS EAST...COLD AIR ADVECTION WILL TAKE PLACE
AND ALLOW WINDS TO MIX DOWN TO THE SURFACE. WILL HOIST A WIND
ADVISORY FOR TONIGHT DUE TO THE POST FRONTAL WINDS EXPECTED.
AS THE STRONG LOW PRESSURE SYSTEM MOVES RATHER QUICKLY TO THE
NORTHEAST...WINDS ARE EXPECTED TO DIMINISH FAIRLY QUICKLY MONDAY
INTO TUESDAY.
CYCLONIC FLOW AROUND THE BACK SIDE OF THE LOW AND IN ADVANCE OF THE
NEXT HIGH PRESSURE WILL CAUSE SHOWERS TO CONTINUE OVER THE EXTREME
NORTHEAST PORTION OF THE FORECAST AREA. OTHERWISE...DRIER AIR WILL
BEGIN TO RETURN BACK TO THE REGION ON MONDAY. THE COLD AIR ADVECTION
WILL LIKELY PRODUCE SOME LAKE EFFECT RAIN AND SNOW SHOWERS OVER THE
NORTHEAST MONDAY NIGHT AND TUESDAY. THE HIGH WILL BUILD IN ACROSS
THE OHIO VALLEY AND SHIFT THE FLOW AWAY FROM THE LAKE ENDING THE
LAKE EFFECT THREAT. OTHERWISE...FAIR WEATHER IS EXPECTED ACROSS THE
REST OF THE FORECAST AREA MONDAY INTO TUESDAY AND OVER ALL AREAS
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT.
THE COLD FRONT WILL RESULT IN COLD AIR ADVECTION AND PLUNGE
TEMPERATURES BACK TO NEAR NORMAL IN THE 40S FOR HIGHS AND OVERNIGHT
LOWS IN THE 20S TO LOWER 30S.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
NOT MANY CHANGES TO THE LONG TERM TODAY. THE NEW GUIDANCE CONTINUES
TO SHOW THE POSSIBILITY OF WARM AIR ADVECTION SHOWERS ON
THURSDAY...ESPECIALLY IN THE WEST. UNSETTLED WEATHER WILL THEN
CONTINUE INTO NEXT WEEKEND AS A SERIES OF FRONTAL SYSTEMS AFFECTS
THE REGION. IT APPEARS BEST CHANCES FOR PRECIP WILL BE FRIDAY NIGHT
INTO SATURDAY AS A WAVE MOVES ACROSS THE OHIO VALLEY. MOST OF THE
PRECIP SHOULD BE LIQUID ALTHOUGH MIXED RAIN AND SNOW COULD OCCUR
EARLY SATURDAY. TEMPS DURING THE PERIOD WILL BE SEASONABLE AND HAVE
STAYED FAIRLY CLOSE TO GUIDANCE.
&&
.AVIATION /18Z SUNDAY THROUGH THURSDAY/...
SOUTHERLY WINDS WILL INCREASE THROUGH THE AFTERNOON WITH GUSTS TO
35 KNOTS COMMON ACROSS THE WEST AND ALONG THE LAKESHORE. EXPECT TO
SEE MVFR CLOUD COVER TO SPREAD BACK INTO THE AREA FROM THE SOUTHWEST.
THIS MAY BE A BIT SLOWER TO OCCUR ACROSS THE EAST BUT WITH SOME
SCATTERED SHOWERS WE EXPECT THERE WILL STILL BE AT LEAST SOME PATCHY
MVFR CONDITIONS.
THE MAIN CONCERN WILL BE THE SEVERE THUNDERSTORM POTENTIAL ALONG A
STRONG COLD FRONT THAT WILL ARRIVE IN THE TOLEDO AREA AROUND
22Z...KCLE AND KMFD AROUND 00Z AND KYNG AND KERI AROUND 02Z.
SEVERE GUSTS WILL BE POSSIBLE WITH THE STRONGEST THUNDERSTORMS.
WINDS IN THE WAKE OF THE FRONT WILL SHIFT TO THE SOUTHWEST AND
INCREASE. MOST LOCATIONS WILL SEE GUSTS 35 TO 40 KNOTS THROUGH THE
OVERNIGHT.
OUTLOOK...NON-VFR CONDITIONS WILL BE SCATTERED ACROSS THE REGION
IN SHOWERS. A FEW SHSN MONDAY NIGHT...MAINLY ACROSS NE OH/NW PA.
CONDITIONS IMPROVING TO VFR FROM WEST TO EAST TUESDAY.
&&
.MARINE...
NO CHANGES TO THE HEADLINES ON THE LAKE TODAY. THE GALE STILL LOOKS
GOOD FOR LATE TODAY AND TONIGHT. STILL EXPECTING A SQUALL LINE TO
MOVE ACROSS THE LAKE THIS EVENING AND WIND GUSTS COULD APPROACH 50
KNOTS. WINDS WILL BECOME WESTERLY BEHIND THE COLD FRONT RESPONSIBLE
FOR THE SQUALL LINE. SPEEDS SHOULD GRADUALLY DIMINISH ON MONDAY AND
EXPECT A PROLONGED PERIOD OF SMALL CRAFT ADVISORIES ONCE THE GALE
COMES DOWN. LOCAL GUIDANCE ALSO SHOWS WATER LEVELS MAKING A RUN FOR
THE CRITICAL MARK LATE TONIGHT. WILL SEE HOW THINGS DEVELOP BUT
LATER SHIFTS MAY NEED TO GO WITH A LOW WATER ADVISORY. THE FLOW
WILL BECOME NW ON MONDAY AS HIGH PRESSURE BEGINS TO BUILD IN FROM
THE WEST. A SURFACE RIDGE WILL EVENTUALLY MOVE EAST OF THE LAKE
TUESDAY NIGHT ALLOWING THE FLOW TO BECOME SOUTHERLY. SOUTH TO
SOUTHWEST FLOW WILL THEN CONTINUE TILL A COLD FRONT CROSSES THE LAKE
AT THE VERY END OF THE PERIOD.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...WIND ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST MONDAY FOR
OHZ003-006>014-017>023-027>033-036>038-047-089.
PA...WIND ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST MONDAY FOR
PAZ001>003.
MARINE...GALE WARNING FROM 6 PM THIS EVENING TO 4 PM EST MONDAY FOR
LEZ061-142>149-162>169.
LOW WATER ADVISORY FROM 7 PM THIS EVENING TO 4 PM EST MONDAY
FOR LEZ142>144-162>164.
&&
$$
SYNOPSIS...KOSARIK/LOMBARDY
NEAR TERM...KOSARIK/LOMBARDY
SHORT TERM...LOMBARDY
LONG TERM...KUBINA
AVIATION...MULLEN
MARINE...KUBINA
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
505 PM EST SUN NOV 17 2013
.SYNOPSIS...
A POTENT STORM SYSTEM WILL BE HEADED ACROSS THE UPPER MIDWEST AND
THROUGH THE GREAT LAKES TODAY AND TONIGHT. THIS WILL BRING A
STRONG COLD FRONT THROUGH THE REGION OVERNIGHT. COOLER AND
DRIER...BUT WINDY CONDITIONS WILL FOLLOW BEHIND THE FRONT ON
MONDAY...WITH HIGH PRESSURE RETURNING FAIR WEATHER TO THE AREA
INTO THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
THE RADAR HASN`T CHANGED APPRECIABLY IN THE LAST SEVERAL HOURS
WITH GENERALLY LIGHT-MODERATE STRATIFORM RAINS CONTINUING OVER
ABOUT THE NWRN 1/2-2/3 OF MY FCST AREA. EXPECT THIS TO CONTINUE
INTO THE EVENING OUT AHEAD OF ALL THE MAIN ACTION THAT IS REALLY
GEARING UP NOW OVER ILLINOIS IN THE FORM OF A VIOLENT SQUALL LINE
THAT HAS ALREADY TRIGGERED SEVERAL DAMAGING TORNADOES.
THE LINE OF STORMS WILL CONTINUE EAST THIS EVENING AND EVENTUALLY
RACE ACROSS OUR AREA LATE THIS EVENING INTO THE WEE HOURS OF
MONDAY MORNING. INSTABILITY WILL AS USUAL BE LIMITED...BUT SHEAR
IS EXTREMELY STRONG. WHILE THE 15Z HRRR AND LATEST WRF RUNS
INDICATE A WEAKENING TREND AS THE LINE MOVES OUR WAY...IT STILL
LOOKS GOOD FOR ISOLATED STRONG WIND GUSTS ALONG AND JUST AHEAD OF
THE COLD FRONT.
BEST TIME FRAME FOR THE WORST OF THE WEATHER OVERNIGHT LOOKS TO BE
ABOUT 03-09Z WHEN THE BIGGEST PWATS AND LOW LEVEL WINDS SURGE
THROUGH THE AREA. 850 WINDS ARE PROGGED IN THE 50-70KT
RANGE...SOME 3-4STD ABOVE NORMAL. WE EXPECT THE LINE TO BRING
BRIEF DOWNPOURS AND THE INITIAL BLAST OF STRONG AND POSSIBLY
DAMAGING WIND GUSTS. THEN OVERALL GRADIENT WINDS SHOULD KICK IN
AND GUST IN THE 25-45MPH RANGE FOR A TIME. SHORT RANGE OPERATIONAL
MODELS ARE SHOWING A STRONG ISSALOBARIC SURGE BEHIND THE FRONT
SUPPORTING THE IDEA OF GUSTY POST FRONTAL WINDS...AT LEAST
THROUGH EARLY MONDAY MORNING WHEN THE STRONGEST WINDS SHOULD THEN
SHIFT OFF TO OUR NORTH AND NORTHEAST. A WIND ADVISORY HAS BEEN
ISSUED FOR LATER TONIGHT THROUGH EARLY MONDAY MORNING.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
THE COLD FRONT SHOULD BE EXITING THE COASTAL PLAIN BY 12Z
MONDAY...LEAVING PA IN A GUSTY WEST-SOUTHWEST FLOW.
TEMPERATURES...AT LEAST INITIALLY WILL NOT BE ALL THAT COLD
WITHIN THE NEW AIRMASS. ANY SHOWERS THAT DEVELOP AS THE COOLER AIR
MOVES OVER THE GREAT LAKES WILL ONLY GRADUALLY MIX WITH WET SNOW
BY THE END OF THE DAY OVER THE NW. THE BULK OF THE REST OF THE
REGION WILL ENJOY THE DRY SLOT...AND DESPITE BEING RATHER WINDY
WILL SEE HIGHS THAT WILL STILL AVERAGE SEVERAL DEG ABOVE NORMAL
FOR NOVEMBER OVER ALL BUT THE FAR NW.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
IN THE WAKE OF FRONTAL/TROF PASSAGE ON MONDAY...UPPER RIDGING WILL
DOMINATE THE MIDDLE ATLANTIC ON TUESDAY AND EARLY WEDNESDAY. UPPER
FLOW WILL THEN TURN SOUTHWESTHERLY THROUGH MUCH OF THE REMAINER OF
THE LONG TERM PERIOD AS A SRN STREAM UPPER LOW IS FORECAST TO
DEVELOP OVER SRN CALIFORNIA. A PRONOUNCED NORTHERN STREAM UPPER TROF
IS FORECAST TO DROP THROUGH THE GREAT LAKES LATE IN THE WEEK AND
TOWARDS PA NEXT WEEKEND.
AT THE SFC...HIGH PRESSURE...EXTENDING FROM NEW ENGLAND TO THE GULF
COAST...WILL DOMINATE MUCH OF WEEK. THIS WILL PROVIDE DRY WEATHER
WITH NEAR SEASONAL TEMPERATURES. THE LATE WEEK UPPER TROF WILL BRING
A COLD FRONT ACROSS PA ON SATURDAY WITH THE MOST SIGNIFICANT CHANCES
FOR PCPN DURING THIS FORECAST PD...NEXT SAT INTO SUNDAY.
TEMPERATURES WILL BE COLD ENOUGH FOR SNOW OR A MIX OF SNOW OR RAIN
OVER A GOOD PORTION OF THE CWA WITH THIS FROPA.
&&
.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
ADJUSTMENTS MADE FOR CURRENT AND EXPECTED CONDITIONS.
EARLIER DISCUSSION BELOW.
WIDESPREAD REDUCED CIG/VIZ IN PLACE AT ALL TERMINALS EXCEPT JST
WHICH IS ON THE EDGE OF THE LOWER CLOUDS AND VIZ ASSOCIATED WITH
THE ADVANCING RAIN.
RADAR TRENDS INDICATE THE NW 1/2-2/3RDS OF THE AIRSPACE WILL SEE
SHOWERS INTO THE EVENING WITH WIDESPREAD IFR/MVFR CONTINUING
TONIGHT WILL BE A VERY ACTIVE PERIOD WITH A STRONG COLD FRONT AND
ATTENDANT LOW-TOPPED SQUALL LINE EXPECTED TO RACE EWD ACROSS THE
AIRSPACE. SOUTHERLY WINDS WILL STEADILY INCREASE AHEAD OF THE
FRONT WITH LLWS EXPECTED GIVEN 50+KT LOW LEVEL JET. MODERATE TO
HEAVY SHOWERS AND LOCAL HIGHER WIND GUSTS WILL BE POSSIBLE ALONG
AND IMMEDIATELY BEHIND THE SQUALL LINE WITH AN ABRUPT WIND SHIFT TO
THE WEST- SOUTHWEST. GUSTY WINDS WILL CONTINUE INTO EARLY MONDAY
WITH FQNT GUSTS IN THE 25-45MPH RANGE..ESPECIALLY OVER WESTERN
AREAS.
MONDAY WILL SEE RAPID IMPROVEMENT IN CEILING/VIZ AS THE FRONT
MOVES OUT OF THE REGION...BUT SOME LOCALLY REDUCED CONDITIONS WILL
BECOME POSSIBLE ONCE AGAIN OVER THE NW AS COOLER AIR BEGINS TO
SWEEP OVER THE GR LAKES AND BRING SOME SCATTERED RAIN/SNOW
SHOWERS. THE WIND WILL STAY GUSTY IN THE 20-35MPH
RANGE...GRADUALLY DIMINISHING IN THE AFTERNOON.
OUTLOOK...
TUE...MAINLY VFR...LOCALLY MVFR OVER THE NW WITH SCATTERED SNOW
SHOWERS.
WED-THU...NO SIG WX.
FRI...SHOWERS POSSIBLE...WITH NEXT FRONTAL SYSTEM.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 11 PM THIS EVENING TO 8 AM EST MONDAY FOR
PAZ004>006-010>012-017>019-024-025-033-034-037-041-042-045-046.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/GARTNER
AVIATION...FITZGERALD/LA CORTE/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
424 PM EST SUN NOV 17 2013
.SYNOPSIS...
A POTENT STORM SYSTEM WILL BE HEADED ACROSS THE UPPER MIDWEST AND
THROUGH THE GREAT LAKES TODAY AND TONIGHT. THIS WILL BRING A
STRONG COLD FRONT THROUGH THE REGION OVERNIGHT. COOLER AND
DRIER...BUT WINDY CONDITIONS WILL FOLLOW BEHIND THE FRONT ON
MONDAY...WITH HIGH PRESSURE RETURNING FAIR WEATHER TO THE AREA
INTO THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
THE RADAR HASN`T CHANGED APPRECIABLY IN THE LAST SEVERAL HOURS
WITH GENERALLY LIGHT-MODERATE STRATIFORM RAINS CONTINUING OVER
ABOUT THE NWRN 1/2-2/3 OF MY FCST AREA. EXPECT THIS TO CONTINUE
INTO THE EVENING OUT AHEAD OF ALL THE MAIN ACTION THAT IS REALLY
GEARING UP NOW OVER ILLINOIS IN THE FORM OF A VIOLENT SQUALL LINE
THAT HAS ALREADY TRIGGERED SEVERAL DAMAGING TORNADOES.
THE LINE OF STORMS WILL CONTINUE EAST THIS EVENING AND EVENTUALLY
RACE ACROSS OUR AREA LATE THIS EVENING INTO THE WEE HOURS OF
MONDAY MORNING. INSTABILITY WILL AS USUAL BE LIMITED...BUT SHEAR
IS EXTREMELY STRONG. WHILE THE 15Z HRRR AND LATEST WRF RUNS
INDICATE A WEAKENING TREND AS THE LINE MOVES OUR WAY...IT STILL
LOOKS GOOD FOR ISOLATED STRONG WIND GUSTS ALONG AND JUST AHEAD OF
THE COLD FRONT.
BEST TIME FRAME FOR THE WORST OF THE WEATHER OVERNIGHT LOOKS TO BE
ABOUT 03-09Z WHEN THE BIGGEST PWATS AND LOW LEVEL WINDS SURGE
THROUGH THE AREA. 850 WINDS ARE PROGGED IN THE 50-70KT
RANGE...SOME 3-4STD ABOVE NORMAL. WE EXPECT THE LINE TO BRING
BRIEF DOWNPOURS AND THE INITIAL BLAST OF STRONG AND POSSIBLY
DAMAGING WIND GUSTS. THEN OVERALL GRADIENT WINDS SHOULD KICK IN
AND GUST IN THE 25-45MPH RANGE FOR A TIME. SHORT RANGE OPERATIONAL
MODELS ARE SHOWING A STRONG ISSALOBARIC SURGE BEHIND THE FRONT
SUPPORTING THE IDEA OF GUSTY POST FRONTAL WINDS...AT LEAST
THROUGH EARLY MONDAY MORNING WHEN THE STRONGEST WINDS SHOULD THEN
SHIFT OFF TO OUR NORTH AND NORTHEAST. A WIND ADVISORY HAS BEEN
ISSUED FOR LATER TONIGHT THROUGH EARLY MONDAY MORNING.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
THE COLD FRONT SHOULD BE EXITING THE COASTAL PLAIN BY 12Z
MONDAY...LEAVING PA IN A GUSTY WEST-SOUTHWEST FLOW.
TEMPERATURES...AT LEAST INITIALLY WILL NOT BE ALL THAT COLD
WITHIN THE NEW AIRMASS. ANY SHOWERS THAT DEVELOP AS THE COOLER AIR
MOVES OVER THE GREAT LAKES WILL ONLY GRADUALLY MIX WITH WET SNOW
BY THE END OF THE DAY OVER THE NW. THE BULK OF THE REST OF THE
REGION WILL ENJOY THE DRY SLOT...AND DESPITE BEING RATHER WINDY
WILL SEE HIGHS THAT WILL STILL AVERAGE SEVERAL DEG ABOVE NORMAL
FOR NOVEMBER OVER ALL BUT THE FAR NW.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
IN THE WAKE OF FRONTAL/TROF PASSAGE ON MONDAY...UPPER RIDGING WILL
DOMINATE THE MIDDLE ATLANTIC ON TUESDAY AND EARLY WEDNESDAY. UPPER
FLOW WILL THEN TURN SOUTHWESTHERLY THROUGH MUCH OF THE REMAINER OF
THE LONG TERM PERIOD AS A SRN STREAM UPPER LOW IS FORECAST TO
DEVELOP OVER SRN CALIFORNIA. A PRONOUNCED NORTHERN STREAM UPPER TROF
IS FORECAST TO DROP THROUGH THE GREAT LAKES LATE IN THE WEEK AND
TOWARDS PA NEXT WEEKEND.
AT THE SFC...HIGH PRESSURE...EXTENDING FROM NEW ENGLAND TO THE GULF
COAST...WILL DOMINATE MUCH OF WEEK. THIS WILL PROVIDE DRY WEATHER
WITH NEAR SEASONAL TEMPERATURES. THE LATE WEEK UPPER TROF WILL BRING
A COLD FRONT ACROSS PA ON SATURDAY WITH THE MOST SIGNIFICANT CHANCES
FOR PCPN DURING THIS FORECAST PD...NEXT SAT INTO SUNDAY.
TEMPERATURES WILL BE COLD ENOUGH FOR SNOW OR A MIX OF SNOW OR RAIN
OVER A GOOD PORTION OF THE CWA WITH THIS FROPA.
&&
.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
WIDESPREAD REDUCED CIG/VIZ IN PLACE AT ALL TERMINALS EXCEPT JST
WHICH IS ON THE EDGE OF THE LOWER CLOUDS AND VIZ ASSOCIATED WITH
THE ADVANCING RAIN.
RADAR TRENDS INDICATE THE NW 1/2-2/3RDS OF THE AIRSPACE WILL SEE
SHOWERS INTO THE EVENING WITH WIDESPREAD IFR/MVFR CONTINUING
TONIGHT WILL BE A VERY ACTIVE PERIOD WITH A STRONG COLD FRONT AND
ATTENDANT LOW-TOPPED SQUALL LINE EXPECTED TO RACE EWD ACROSS THE
AIRSPACE. SOUTHERLY WINDS WILL STEADILY INCREASE AHEAD OF THE
FRONT WITH LLWS EXPECTED GIVEN 50+KT LOW LEVEL JET. MODERATE TO
HEAVY SHOWERS AND LOCAL HIGHER WIND GUSTS WILL BE POSSIBLE ALONG
AND IMMEDIATELY BEHIND THE SQUALL LINE WITH AN ABRUPT WIND SHIFT TO
THE WEST- SOUTHWEST. GUSTY WINDS WILL CONTINUE INTO EARLY MONDAY
WITH FQNT GUSTS IN THE 25-45MPH RANGE..ESPECIALLY OVER WESTERN
AREAS.
MONDAY WILL SEE RAPID IMPROVEMENT IN CEILING/VIZ AS THE FRONT
MOVES OUT OF THE REGION...BUT SOME LOCALLY REDUCED CONDITIONS WILL
BECOME POSSIBLE ONCE AGAIN OVER THE NW AS COOLER AIR BEGINS TO
SWEEP OVER THE GR LAKES AND BRING SOME SCATTERED RAIN/SNOW
SHOWERS. THE WIND WILL STAY GUSTY IN THE 20-35MPH
RANGE...GRADUALLY DIMINISHING IN THE AFTERNOON.
OUTLOOK...
TUE...MAINLY VFR...LOCALLY MVFR OVER THE NW WITH SCATTERED SNOW
SHOWERS.
WED-THU...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 11 PM THIS EVENING TO 8 AM EST MONDAY FOR
PAZ004>006-010>012-017>019-024-025-033-034-037-041-042-045-046.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/GARTNER
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
141 PM EST SUN NOV 17 2013
.SYNOPSIS...
A POTENT STORM SYSTEM WILL BE HEADED ACROSS THE UPPER MIDWEST AND
THROUGH THE GREAT LAKES TODAY AND TONIGHT. THIS WILL BRING A
STRONG COLD FRONT THROUGH THE REGION OVERNIGHT. COOLER AND
DRIER...BUT WINDY CONDITIONS WILL FOLLOW BEHIND THE FRONT ON
MONDAY...WITH HIGH PRESSURE RETURNING FAIR WEATHER TO THE AREA
INTO THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE RADAR HASN`T CHANGED APPRECIABLY IN THE LAST SEVERAL HOURS
WITH GENERALLY LIGHT-MODERATE STRATIFORM RAINS CONTINUING OVER
ABOUT THE NWRN 1/2-2/3 OF MY FCST AREA. EXPECT THIS TO CONTINUE
INTO THE EVENING OUT AHEAD OF ALL THE MAIN ACTION THAT IS REALLY
GEARING UP NOW OVER ILLINOIS IN THE FORM OF A VIOLENT SQUALL LINE
THAT HAS ALREADY TRIGGERED SEVERAL DAMAGING TORNADOES.
THE LINE OF STORMS WILL CONTINUE EAST THIS EVENING AND EVENTUALLY
RACE ACROSS OUR AREA LATE THIS EVENING INTO THE WEE HOURS OF
MONDAY MORNING. INSTABILITY WILL AS USUAL BE LIMITED...BUT SHEAR
IS EXTREMELY STRONG. WHILE THE 15Z HRRR AND LATEST WRF RUNS
INDICATE A WEAKENING TREND AS THE LINE MOVES OUR WAY...IT STILL
LOOKS GOOD FOR ISOLATED STRONG WIND GUSTS ALONG AND JUST AHEAD OF
THE COLD FRONT.
BEST TIME FRAME FOR THE WORST OF THE WEATHER OVERNIGHT LOOKS TO BE
ABOUT 03-09Z WHEN THE BIGGEST PWATS AND LOW LEVEL WINDS SURGE
THROUGH THE AREA. 850 WINDS ARE PROGGED IN THE 50-70KT
RANGE...SOME 3-4STD ABOVE NORMAL. WE EXPECT THE LINE TO BRING
BRIEF DOWNPOURS AND THE INITIAL BLAST OF STRONG AND POSSIBLY
DAMAGING WIND GUSTS. THEN OVERALL GRADIENT WINDS SHOULD KICK IN
AND GUST IN THE 25-45MPH RANGE FOR A TIME. SHORT RANGE OPERATIONAL
MODELS ARE SHOWING A STRONG ISSALOBARIC SURGE BEHIND THE FRONT
SUPPORTING THE IDEA OF GUSTY POST FRONTAL WINDS...AT LEAST
THROUGH EARLY MONDAY MORNING WHEN THE STRONGEST WINDS SHOULD THEN
SHIFT OFF TO OUR NORTH AND NORTHEAST. A WIND ADVISORY HAS BEEN
ISSUED FOR LATER TONIGHT THROUGH EARLY MONDAY MORNING.
&&
.SHORT TERM /MONDAY/...
THE COLD FRONT SHOULD BE EXITING THE COASTAL PLAIN BY 12Z
MONDAY...LEAVING PA IN A GUSTY WEST-SOUTHWEST FLOW.
TEMPERATURES...AT LEAST INITIALLY WILL NOT BE ALL THAT COLD
WITHIN THE NEW AIRMASS. ANY SHOWERS THAT DEVELOP AS THE COOLER AIR
MOVES OVER THE GREAT LAKES WILL ONLY GRADUALLY MIX WITH WET SNOW
BY THE END OF THE DAY OVER THE NW. THE BULK OF THE REST OF THE
REGION WILL ENJOY THE DRY SLOT...AND DESPITE BEING RATHER WINDY
WILL SEE HIGHS THAT WILL STILL AVERAGE SEVERAL DEG ABOVE NORMAL
FOR NOVEMBER OVER ALL BUT THE FAR NW.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
SCATTERED LIGHT PRECIPITATION /INITIALLY IN THE FORM OF RAIN SHOWERS
DURING THE DAYLIGHT HOURS MONDAY...THEN EVENTUALLY SNOW SHOWERS BY
MONDAY NIGHT/...WILL AFFECT THE NORTHERN AND WESTERN MOUNTAINS OF
THE STATE. MINOR SNOW ACCUMS OF A COATING...TO PERHAPS AROUND 1 INCH
IN WARREN COUNTY...WILL OCCUR MONDAY NIGHT ACROSS THE MTNS. BIG
NEGATING FACTOR AGAINST ACCUMULATING OROGRAPHIC/LES SNOW SHOWERS
WILL BE THE RATHER SHALLOW DEPTH OF THE COLD AIR...AND CLOUD TEMPS
WARMER THAN -12C WHICH WILL GREATLY LIMIT THE INTENSITY AND
DENDRITIC GROWTH OF THE SNOW.
AFTER PASSAGE OF UPPER TROF AXIS MONDAY/EARLY TUESDAY...THE UPPER
FLOW PATTERN BECOMES FAIRLY ZONAL THROUGH THE REMAINDER OF THE
PERIOD AS ENERGY IS FORECAST TO DIG INTO THE WESTERN U.S. 00Z MODEL
GUIDANCE IS SOMEWHAT GOOD AGREEMENT ON A DRY AND SLOWLY MODERATING
PERIOD FOR THE SECOND HALF OF THE WEEK AS HIGH PRESSURE SLIDES OFF
THE SOUTHERN NEW ENGLAND COAST.
AN ARCTIC FRONT WILL PLOW SOUTHEAST ACROSS THE NORTHERN PLAINS AND
UPPER GLAKES FRIDAY...THANKS TO A HIGHLY AMPLIFIED RIDGE FORMING
ACROSS THE ERN PACIFIC AND INTO THE GULF OF ALASKA...WITH AN
EVENTUAL REX BLOCK PATTERN OVER THE WEST COAST OF CANADA AND
THE U.S.
INTERESTING SCENARIO SHAPING UP FOR NEXT WEEKEND WITH THE FIRST
POTENTIAL FOR A WIDESPREAD SYNOPTIC LIGHT TO MODERATE SNOW OR MIXED
PRECIP EVENT. 00Z GFS AND EC OPERATIONAL MODELS AND ENSEMBLE SUITES
DIVERGE SLIGHTLY BY NEXT WEEKEND WITH THE TRACK/ORIENTATION OF THE
ARCTIC FRONT...AND THE AMOUNT OF ENERGY DIGGING SOUTHEAST IN ITS
WAKE INTO THE MISS VALLEY AND APPALACHIANS.
HOWEVER...BOTH MODELS AND THEIR ENSEMBLES INDICATE A CLIPPER TYPE
SYSTEM HEADING SE ACROSS THE GLAKES...BRINGING US AT LEAST SOME
SNOW/OR SNOW SHOWERS /THAT COULD BE MIXED WITH RAIN ACROSS SOUTHERN
PENN FRIDAY NIGHT INTO EARLY SAT/. THE COLDEST AIR SO FAR THIS FALL
WILL LIKELY FOLLOW FOR LATER NEXT WEEKEND INTO THE WEEK OF NOV 25TH.
&&
.AVIATION /17Z SUNDAY THROUGH THURSDAY/...
WIDESPREAD REDUCED CIG/VIZ IN PLACE AT ALL TERMINALS EXCEPT JST
WHICH IS ON THE EDGE OF THE LOWER CLOUDS AND VIZ ASSOCIATED WITH
THE ADVANCING RAIN.
RADAR TRENDS INDICATE THE NW 1/2-2/3RDS OF THE AIRSPACE WILL SEE
SHOWERS INTO THE EVENING WITH WIDESPREAD IFR/MVFR CONTINUING
TONIGHT WILL BE A VERY ACTIVE PERIOD WITH A STRONG COLD FRONT AND
ATTENDANT LOW-TOPPED SQUALL LINE EXPECTED TO RACE EWD ACROSS THE
AIRSPACE. SOUTHERLY WINDS WILL STEADILY INCREASE AHEAD OF THE
FRONT WITH LLWS EXPECTED GIVEN 50+KT LOW LEVEL JET. MODERATE TO
HEAVY SHOWERS AND LOCAL HIGHER WIND GUSTS WILL BE POSSIBLE ALONG
AND IMMEDIATELY BEHIND THE SQUALL LINE WITH AN ABRUPT WIND SHIFT TO
THE WEST- SOUTHWEST. GUSTY WINDS WILL CONTINUE INTO EARLY MONDAY
WITH FQNT GUSTS IN THE 25-45MPH RANGE..ESPECIALLY OVER WESTERN
AREAS.
MONDAY WILL SEE RAPID IMPROVEMENT IN CEILING/VIZ AS THE FRONT
MOVES OUT OF THE REGION...BUT SOME LOCALLY REDUCED CONDITIONS WILL
BECOME POSSIBLE ONCE AGAIN OVER THE NW AS COOLER AIR BEGINS TO
SWEEP OVER THE GR LAKES AND BRING SOME SCATTERED RAIN/SNOW
SHOWERS. THE WIND WILL STAY GUSTY IN THE 20-35MPH
RANGE...GRADUALLY DIMINISHING IN THE AFTERNOON.
OUTLOOK...
TUE...MAINLY VFR...LOCALLY MVFR OVER THE NW WITH SCATTERED SNOW
SHOWERS.
WED-THU...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 11 PM THIS EVENING TO 8 AM EST MONDAY FOR
PAZ004>006-010>012-017>019-024-025-033-034-037-041-042-045-046.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/GARTNER
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
205 PM CST SUN NOV 17 2013
.DISCUSSION...
IN THE SHORT TERM...CLOUDY SKIES HANGING ON TOUGH ACROSS THE EAST
AND SOUTH WITH THE LOW LEVEL MOISTURE AXIS. TO THE NORTH AND WEST
MIDLEVEL DRY HAS SURGED AHEAD OF THE FRONTAL BOUNDARY AND HAS
PROVIDED MOSTLY CLEAR SKIES AND GOOD MIXING IN THE BOUNDARY LAYER
BUT LIKELY CAPPED JUST ABOVE. AS OF 20Z THE COLD FRONT/DRYLINE IS
NOW CROSSING LAWRENCE AND RANDOLPH COUNTIES WITH CONVECTION REALLY
STRUGGLING TO GET GOING DESPITE THE CLEARING AND DEWPOINTS NEAR
70F. WITH THIS SAID...THE NAM...GFS AND HRRR MODELS SHOW THE
FRONT BECOMING SOMEWHAT MORE ACTIVE ACROSS NORTHWEST TENNESSEE
BETWEEN 21-00Z. THIS STILL SEEMS VERY CONDITIONAL AND ISOLATED AS
MAX TEMPERATURES WILL START TO FALL. WILL BE TRIMMING BACK THE
CURRENT TORNADO WATCH BY 4 PM FOR THE COUNTIES WEST OF THE RIVER.
FURTHER SOUTH...FEEL RAIN SHOWERS WILL BE MORE LIKELY ESPECIALLY
THIS EVENING AS THE TAIL OF THE FRONT PASSES THROUGH NORTHEAST
MISSISSIPPI. THE SOUTHWEST DELTA COUNTIES WILL HAVE THE LOWEST
RAIN CHANCES FOR THE REMAINDER OF THE DAY. SKIES WILL CLEAR OUT
ACROSS THE SOUTH DURING THE NIGHT WITH SOME PATCHY FOG POSSIBLE.
MONDAY THROUGH WEDNESDAY...SURFACE HIGH PRESSURE WILL KEEP THE
MIDSOUTH DRY WITH NEAR SEASONAL TEMPERATURES. WINDS WILL VEER FROM
NORTH ON MONDAY TO SOUTHEASTERLY ON WEDNESDAY. LOWS TUESDAY AND
WEDNESDAY MORNING WILL BE NEAR FREEZING OVER THE NORTH AND EAST.
WEDNESDAY NIGHT THROUGH SUNDAY...GFS AND ECMWF BECOMING MORE IN
LINE DURING THIS PERIOD THAT WAA AND ISENTROPIC LIFT WILL GENERATE
LIGHT RAIN SHOWER ACTIVITY ACROSS THE MIDWEST FIRST...AND THEN
EXTEND IT SOUTHWARD ON THURSDAY. THIS IS IN RESPONSE TO A
DESCENDING 1040MB SURFACE HIGH IN THE NORTHERN PLAINS...AS IT
GENERATES A NEW COLD FRONT OVER THE MIDWEST. THIS BOUNDARY IS
FORECASTED TO SLOWLY PUSH SOUTH THROUGH OUR AREA THURSDAY NIGHT
THROUGH FRIDAY AND INTO EARLY SATURDAY. THUS THE END OF THE WORK
WEEK LOOKS TO BE COOL AND WET. THOUGH WITH THE LACK OF ANY
SIGNIFICANT UPPER LEVEL SUPPORT THUNDERSTORMS WILL BE MINIMAL. AS
THE FRONT MOVES TOWARDS THE GULF COAST ON SATURDAY...NORTH WINDS
WILL KEEP THE WEEKEND HIGHS TEN TO FIFTEEN DEGREES BELOW
NORMAL...WITH MAINLY 40S TO LOW 50S.
JAB
&&
.AVIATION...
A MID LEVEL DRY SLOT WILL CONTINUE TO ROTATE NORTHEASTWARD INTO
NORTHERN PORTIONS OF THE MID SOUTH HELPING TO MIX OUT LOW LEVEL
STRATUS. THIS SHOULD BE COMMON WITHIN THE NEXT FEW HOURS AT
KJBR...KMKL...AND KMEM WITH CIGS EVENTUALLY GOING VFR. FURTHER
SOUTH...LOW LEVEL MOISTURE AXIS WILL LIKELY MAINTAIN A LONGER TIME
PERIOD WITH IFR TO MVFR CIGS PERSISTING THROUGH MUCH OF THE
AFTERNOON. SHOWER AND THUNDERSTORMS POTENTIAL REMAINS MUCH MORE
CONDITIONAL ACROSS OUR REGION THIS AFTERNOON AND THIS EVENING.
BEST POTENTIAL WILL REMAIN ACROSS OUR NORTHERN TIER COUNTIES WITH
THE BEST POTENTIAL AT KMKL WHERE A TEMPO HAS BEEN MAINTAINED FOR
LATER THIS AFTERNOON. THIS WILL BE MONITORED THROUGH THE DAY AS
TEMPO COVERAGE MAY STILL BE TOO HIGH. FOR NOW...HAVE KEPT A
VICINITY THUNDER MENTION AT KMEM AND KJBR. AGAIN MAY NEED TO PULL
THIS WITHIN THE NEXT FEW HOURS AS BEST LIFT REMAINS NORTH. STRONG
AND GUSTY SOUTHWEST WINDS WILL BE LIKELY AT ALL TERMINALS THROUGH
THE EARLY EVENING HOURS.
THE FRONT WILL COME ACROSS THE TERMINALS FROM WEST TO EAST THIS
EVENING WITH SKIES CLEARING AND WINDS BECOMING NORTHWESTERLY AND
WEAKENING AS HIGH PRESSURE BUILDS IN. LATER TONIGHT CLEAR SKIES
AND DIMINISHED WINDS ARE EXPECTED AND WILL CONTINUE THROUGH MID
DAY MONDAY.
JLH
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 49 63 41 59 / 20 0 0 0
MKL 43 62 35 57 / 20 0 0 0
JBR 43 61 36 55 / 10 0 0 0
TUP 48 66 38 60 / 40 0 0 0
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WIND ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR CLAY-CRAIGHEAD-
CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI-
PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...WIND ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR DUNKLIN-PEMISCOT.
MS...WIND ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR ALCORN-BENTON MS-
CALHOUN-COAHOMA-DESOTO-LAFAYETTE-MARSHALL-PANOLA-PONTOTOC-
QUITMAN-TALLAHATCHIE-TATE-TIPPAH-TUNICA-UNION-YALOBUSHA.
TN...WIND ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR CARROLL-CHESTER-
CROCKETT-DECATUR-DYER-FAYETTE-GIBSON-HARDEMAN-HARDIN-
HAYWOOD-HENDERSON-HENRY-LAKE-LAUDERDALE-MADISON-MCNAIRY-
OBION-SHELBY-TIPTON-WEAKLEY.
&&
$$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1216 PM CST SUN NOV 17 2013
.MESOSCALE UPDATE...
REGIONAL RADAR IMAGERY IS SHOWING AN INTENSE LINE OF
SEVERE/TORNADIC THUNDERSTORMS EXTENDING SOUTHWARD FROM NORTHERN IL
INTO SOUTHEAST MO. THIS LINE IS DEVELOPING JUST AHEAD OF A STRONG
COLD FRONT...WHICH ALSO HAS A THINNER LINE OF STORMS ALONG
IT...FURTHER WEST TOWARDS THE IA/IL BORDER. THE INITIAL LINE OF
STORMS COULD CONTINUE TO FILL IN SOUTHWARD. A RUC SOUNDING FROM
THE BOOTHEEL OF MO SHOWS PLENTY OF CAPE (WELL OVER 1000 J/KG) OVER
THE NEXT FEW HOURS. ONLY CONCERN FOR STORMS NOT CONTINUING TO
BUILD SOUTHWARD ALONG THE PRE-FRONTAL LINE WOULD BE A LITTLE
WARMING FORECAST IN THE NAM/GFS MODELS AROUND 800MB WHICH COULD
CAP OUR REGION AHEAD OF THE FRONT. GOOD LOW-LEVEL MOISTURE
CONVERGENCE NEAR THE TN/MO/AR BORDER THOUGH COULD OVERCOME THAT.
WILL HAVE TO MONITOR OVER THE NEXT COUPLE OF HOURS...BUT THAT WAS
THE REASON FOR THE TOR WATCH BEING ISSUED TO OUR WEST.
IF STORMS DO IN FACT CONTINUE TO BUILD SOUTH...THE LINE SHOULD BE
THINNER AND LESS POTENT THAN THE INTENSE STORMS ACROSS THE LOWER
GREAT LAKES REGION AT THE MOMENT (AS EVIDENCED BY ACTIVITY OVER NE
AR FORMING NOW). YET THESE STORMS COULD STILL POSE THE DAMAGING
WIND/ISOLATED TORNADO THREAT HERE MOST LIKELY AFTER 3PM OVER OUR
FAR WESTERN COUNTIES.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR TNZ009>011-028>034-
062>066-075-077>080.
WIND ADVISORY UNTIL 10 PM CST THIS EVENING FOR TNZ005>008-
022>027-056>061-093>095.
&&
$$
AL
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1050 AM CST SUN NOV 17 2013
.UPDATE...
UPDATED FOR TORNADO WATCH.
&&
.DISCUSSION...
TORNADO WATCH THROUGH 7 PM LST NORTH OF A HARRISBURG ARKANSAS TO
HUNTINGDON TENNESSEE LINE. CURRENT DRY LINE ACROSS NORTH CENTRAL
ARKANSAS AND SOUTH CENTRAL MISSOURI WILL LIKELY BECOME MORE
ATICVE OVER THE NEXT FEW HOURS AS IT PUSHES TOWARDS THE MS RIVER.
A FEW OF THESE STORMS MAY BECOME SEVERE WITH DAMAGING WINDS AND A
POSSIBLE BRIEF TORNADO. HAVE ADJUSTED THE HWO ACCORDINGLY.
JAB
&&
.PREV DISCUSSION... /ISSUED 944 AM CST SUN NOV 17 2013/
UPDATE...
UPDATED TO REDUCE MORNING AND AFTERNOON RAIN CHANCES AND TO ADJUST
SEVERE WEATHER WORDING.
DISCUSSION...
FIRST...CONVECTION WITH THE LOW LEVEL INSTABILITY AXIS MOVING
FASTER EAST THAN PREVIOUSLY FORECASTED...SO HAVE ADJUSTED RAIN
CHANCES ACCORDINGLY FOR THE REMAINDER OF THE MORNING.
SECOND...AFTER ANALYSIS OF THE HRRR MODEL...CURRENT SIGNIFICANT
MIXING IN THE OBSERVATIONS AHEAD OF THE FRONT IN NORTHWEST
ARKANSAS...AND STRONG CAP DEVELOPING AHEAD OF THE FRONT OFF OF
12Z SGF SOUNDING...IT APPEARS THAT THE SEVERE THREAT WILL REMAIN
ACROSS THE NORTHERN AND EASTERN COUNTIES FOR THIS AFTERNOON WHERE
FRONTAL FORCING WILL BE STRONGEST. HELICITY VALUES NEAR 200
M^2/S^2 SUGGESTS WEAK TORNADOES WILL STILL BE POSSIBLE...THOUGH
DAMAGING WIND GUSTS IS STILL THE PRIMARY SEVERE THREAT. HAVE
ADJUSTED THE HWO ACCORDINGLY.
THIRD...MADE SOME ADJUSTMENTS TO AFTERNOON CLOUD COVER AS MORE BREAKS
IN THE LOW LEVEL MOISTURE IS ANTICIPATED...AIDING THE SOUTH TO
SOUTHWEST WINDS TO REACH THE WIND ADVISORY CRITERIA EAST OF THE MS RIVER.
JAB
PREV DISCUSSION... /ISSUED 523 AM CST SUN NOV 17 2013/
DISCUSSION... /ISSUED 458 AM CST SUN NOV 17 2013/
EARLY MORNING GOES WATER IMAGERY SHOWED A DEEP UPPER LEVEL TROF
OVER THE CENTRAL AND NORTHERN PLAINS. THIS FEATURE WAS LIFTING
EAST AND BECOMING NEGATIVELY TILTED. A 160KT 200MB JET EXTENDED
FROM NORTH TX ACROSS THE OZARK PLATEAU...WITH INCREASINGLY
DIFFLUENT FLOW EVIDENT DOWNSTREAM OF THE JET CORE. CLOSER TO
HOME... THUNDERSTORMS HAD FORMED ON THE SOUTHERN FLANK OF THE JET
CORE OVER NORTHERN AR...INTO WEST TN. THIS CONVECTION WAS ROOTED
IN AN ELEVATED LAYER...THUS FAR UNABLE TO TAP INTO THE GREATER
HELICITY EMBEDDED IN A WEAK NOCTURNAL INVERSION BELOW 925MB.
EXPECT THE SHOWERS AND THUNDERSTORMS TO SHIFT EASTWARD THROUGH THE
DAY PERHAPS LEAVING AREAS WEST OF THE RIVER FREE OF RAIN LATER THIS
MORNING.
LATE MORNING AND EARLY AFTERNOON SEVERE CHANCES WILL LIKELY DEPEND
ON STORMS BECOMING ROOTED IN THE BOUNDARY LAYER... TAPPING BETTER
DIRECTIONAL SHEAR FOR MORE PERSISTENT AND ORGANIZED STORM STRUCTURES.
NAM BUFR SOUNDINGS SUGGESTS THIS IS A DISTINCT POSSIBILITY...PARTICULARLY
IN THE 18Z TO 21Z TIME FRAME. STORMS WILL HAVE BETTER CHANCES OF
BECOMING SURFACED BASED WITH THE ARRIVAL OF A SURFACE COLD FRONT
INTO EASTERN AR AROUND 21Z/3PM. STORMS MAY REFORM AS FAR WEST AS
JONESBORO...FORMING A LINE THAT WILL PROGRESS SOUTHEAST INTO THE
NORTHEAST MS TOWARD 03Z/9 PM. MAIN SEVERE WEATHER THREAT ACROSS
THE MIDSOUTH WILL DAMAGING STRAIGHT LINE WINDS. 06Z NAM PROGGED
700MB WEST/SOUTHWEST WINDS OF 60 TO 75 KTS NORTH OF I40 THIS
AFTERNOON...PERHAPS LEADING TO SOME BOWING LINE SEGMENTS. THERE
WILL BE SUFFICIENT HELICITY AND CAPE FOR SECONDARY TORNADO
THREAT DURING THE MID TO LATE AFTERNOON.
THE NAM PROGGED 03Z/9PM SURFACE CAPE NEAR 1000 J/KG AND 3KM
HELICITY NEAR 300 M2/S2 AT TUPELO. STORMS ALONG THE ADVANCING COLD
FRONT WILL HAVE A SHOT AT BECOMING ROOTED IN THE BOUNDARY LAYER.
OTHERWISE...HIGHER CINH AND LOWER ELEVATED CAPE SHOULD PREVAIL
OVER NORTH MS AS THE NOCTURNAL INVERSION FORMS.
TRANQUIL WEATHER WILL PREVAIL MONDAY THROUGH WEDNESDAY...COURTESY
OF PACIFIC SURFACE HIGH PRESSURE AND ZONAL FLOW ALOFT. GFS AND
ECMWF HAVE COME INTO BETTER AGREEMENT WITH RESPECT TO THE SPLIT
UPPER LEVEL FLOW PATTERN LATE IN THE WEEK. BY THURSDAY...MIDLEVEL
PACIFIC SUBTROPICAL MOISTURE WILL ACCOMPANY MODEST LOW LEVEL WARM
ADVECTION TO SUPPORT A RETURN OF SCATTERED SHOWERS TO THE MIDSOUTH.
BY LATE FRIDAY... COLLAPSING HEIGHTS OVER THE GREAT LAKES AND UPPER
MIDWEST WILL DRIVE A SURFACE COLD FRONT THE MIDSOUTH LATE FRIDAY.
COOLER AND MUCH DRIER MODIFIED ARCTIC AIR WILL SPREAD IN SATURDAY...
WITH MIDLEVEL CLOUDS AND MOISTURE LIKEWISE PUSHING OFF TO THE
SOUTH...INTO THE NORTHERN GULF OF MEXICO. NEXT WEEKEND/S WEATHER
SHOULD BE MORE TYPICAL OF LATE NOVEMBER.
PWB
&&
.AVIATION...
12Z TAF SET
IFR CIGS STILL HAVE YET TO MATERIALIZE EXCEPT AT KTUP. AREA OF
SHRAS WITH EMBEDDED TSRAS CONTINUES TO DEVELOP AND PUSH EAST
ACROSS THE CWA. CAN/T RULE OUT CIGS LOWERING TO IFR UNDERNEATH THE
HEAVIER SHRAS/TSRAS...OTHERWISE EXPECT MVFR CONDITIONS TO PREVAIL
THROUGH MUCH OF THE DAY AGAIN WITH THE POSSIBLE EXCEPTION OF KTUP.
WOULD NOT BE SURPRISED TO SEE CONDITIONS RETURN TO VFR AT
LOCATIONS SUCH AS KMEM AND KJBR THIS AFTERNOON. REDEVELOPMENT OF
TSRAS IS EXPECTED ALONG THE FRONT THIS AFTERNOON INTO THIS
EVENING. BEST CHANCES WILL OCCUR AT KMKL AND KTUP BETWEEN 23Z-05Z.
SKIES WILL QUICKLY CLEAR BEHIND THE FRONT. STRONG S TO SW WINDS
EXPECTED TODAY WITH SUSTAIN SPEEDS OF 10-17 KTS WITH GUSTS BETWEEN
15-28 KTS. WINDS WILL TURN AROUND TO THE NW AND EVENTUALLY N
BEHIND THE FRONT. SPEEDS WILL DIMINISH TO BETWEEN 5-10 KTS AS WELL
DURING THE OVERNIGHT HOURS.
KRM
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 78 46 62 40 / 100 20 0 0
MKL 76 41 61 34 / 100 30 0 0
JBR 79 42 60 35 / 60 10 0 0
TUP 76 46 65 37 / 100 40 0 0
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WIND ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR CLAY-CRAIGHEAD-
CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI-
PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...WIND ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR DUNKLIN-PEMISCOT.
MS...WIND ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR ALCORN-BENTON MS-
CALHOUN-COAHOMA-DESOTO-LAFAYETTE-MARSHALL-PANOLA-PONTOTOC-
QUITMAN-TALLAHATCHIE-TATE-TIPPAH-TUNICA-UNION-YALOBUSHA.
TN...WIND ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR CARROLL-CHESTER-
CROCKETT-DECATUR-DYER-FAYETTE-GIBSON-HARDEMAN-HARDIN-
HAYWOOD-HENDERSON-HENRY-LAKE-LAUDERDALE-MADISON-MCNAIRY-
OBION-SHELBY-TIPTON-WEAKLEY.
&&
$$
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
357 PM EST SUN NOV 17 2013
.SYNOPSIS...
LOW PRESSURE WAS OVER THE GREAT LAKES WITH A STRONG COLD FRONT
EXTENDING FROM THE LOW INTO THE SOUTHERN PLAINS. THIS FRONT WILL
RACE EAST TONIGHT AND WILL BE OFF THE COAST BY MONDAY AFTERNOON. COLD
HIGH PRESSURE SETTLES OVER THE GREAT LAKES TUESDAY AND WEDNESDAY
BRINGING DRIER WEATHER INTO THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
AS OF 345 PM EST SUNDAY...
RAPIDLY CHANGING WEATHER TONIGHT AND MONDAY. AREA OF LIGHT TO
MODERATE SHOWERS WAS MOVING INTO THE WESTERN COUNTY WARNING AREA
AS OF 300PM. LOCAL WRF...HRRR AND RAP MODELS HAVE THESE SHOWERS
MOVING EAST ACROSS THE FORECAST AREA BY MIDNIGHT.
INTENSE COLD FRONT EXTENDED FROM NORTHERN ILLINOIS INTO CENTRAL
ARKANSAS. THIS FRONT WILL MOVE QUICKLY EAST AND WILL REACH THE
WESTERN COUNTIES OF THE FORECAST AREA AROUND 11PM. AHEAD OF THE
FRONT THE LOW LEVEL JET INCREASES...WITH 850 MB WINDS IN THE 50 TO
60 KNOT RANGE. HAVE EXPANDED THE WIND ADVISORY INTO TAZEWELL
COUNTY FOR TONIGHT.
STILL A THREAT OF STRONG TO DAMAGING WINDS AFTER MIDNIGHT WITH THE
BAND OF SHOWERS AND POSSIBLY ISOLATED THUNDERSTORMS ALONG THE
FRONT. THE FRONT IS EXPECTED TO EXIT THE EASTERN COUNTY WARNING
AREA BETWEEN 4AM AND 7AM.
NOT MUCH DROP IN TEMPERATURES UNTIL THE FRONT GOES THROUGH THEN ON
MONDAY NOT MUCH RECOVERY OF TEMPERATURES WITH MODERATE COLD AIR
ADVECTION. STRONG ENOUGH PRESSURE RISES...IN THE +5 TO +10
MB/6HR RANGE TO ENHANCE THE WINDS FOR MUCH OF THE DAY.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
AS OF 311 PM EST SUNDAY...
STILL A GRADIENT LEFT MONDAY NIGHT ALTHOUGH SURFACE HIGH PRESSURE IS
ON APPROACH. LEFTOVER WINDS COMBINED WITH SOME CLOUDS ACROSS SE WEST
VA WILL KEEP TEMPS A LITTLE WARMER THAN THEY WOULD BE IF THE CENTER
OF THE SURFACE HIGH WAS PARKED OVERHEAD. INTO TUESDAY
AFTERNOON...HIGH PRESSURE BEGINS A TRIP TOWARDS PENNSYLVANIA AND NEW
ENGLAND...EVENTUALLY IN THE QUINTESSENTIAL WEDGE POSITION FOR
WEDNESDAY. WITH DOWNSLOPING FLOW REMOVED...COLDER H85 VALUES AROUND
0C WILL COVER MOST OF THE CWA UNDER CLEAR SKIES TUESDAY. DEWPOINTS
MAY FALL INTO THE LOWER 20S AND UPPER TEENS SETTING THE STAGE FOR A
VERY COLD TUESDAY NIGHT...IF MID AND HIGH CLOUDS HOLD OFF FROM THE
SOUTH...AND DEVELOPING EASTERLY FLOW REMAINS WEAK. INCREASING
MID/HIGH CLOUDS WEDNESDAY...A VERY COLD START AND SUBTLE EASTERLY
BREEZES WITHIN THE WEDGE MAY KEEP MOST LOCATIONS BELOW 50F FOR
WEDNESDAY...WHICH IS BELOW THE MEX/ECMWF MOS NUMBERS.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 340 PM EST SUNDAY...
A FEW CHANGES IN THE EXTENDED FORECAST BUT STILL LOOKS WET FRIDAY
NIGHT INTO SATURDAY EVENING. MODELS ARE ARGUING WHICH WEATHER
FEATURE WILL BRING RAIN TO THE AREA. THE 12Z GFS FAVORS A SHORT
COMING ACROSS THE TENN VALLEY AND OVER THE WEDGE THURSDAY NIGHT.
FRIDAY AND FRIDAY NIGHT...THE GFS HAS WAVES RIDING ALONG THE
FRONT..EVENTUALLY PUSHING THE COLD FRONT TO THE EAST COAST SATURDAY
MORNING. THE 12Z ECMWF HAS A COLD FRONT MOVING SLOWLY TO THE
EAST...FROM MISSISSIPPI VALLEY THURSDAY NIGHT...INTO THE OHIO VALLEY
FRIDAY AFTERNOON...THEN STALLS IT OVER THE MID ATLANTIC-SOUTHERN
APPALACHIAN MOUNTAINS SATURDAY MORNING. A SURFACE WAVE THEN DEVELOPS
ALONG THE FRONT...POSSIBLY OVER THE FORECAST AREA SATURDAY. THIS
WAVE WILL THEN TRACK NORTHEAST...PULLING THE FRONT ACROSS THE REGION
BY SATURDAY EVENING. SINCE THERE IS DISCONTINUITY BETWEEN MODELS AND
RUN-TO-RUN WITH EACH MODEL...WILL KEEP POPS IN A 20-40 PERCENT RANGE
FRIDAY AFTERNOON INTO SATURDAY AFTERNOON.
WITH EITHER MODEL AND/OR SCENARIO...THE GULF IS OPEN TO BRING THE
AREA MUCH NEEDED RAIN FRIDAY INTO SATURDAY. ALSO...MILD TO WARM
TEMPERATURES LIKELY FRIDAY...DEPENDING ON IF A LOCATION SEES RAIN.
ONCE THE FRONT MOVES TO THE COAST...85H TEMPERATURES DROP TO -10C.
&&
.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
AS OF 1250 AM EST SUNDAY...
SIGNIFICANT CHANGES WILL BE OCCURRING DURING THE TAF PERIOD.
LIFR TO IFR STRATUS AND FOG EAST OF THE BLUE RIDGE WILL GRADUALLY
LIFT AS A SURFACE WEDGE ERODES AND WINDS BECOME SOUTH TO
SOUTHWEST. THE VISIBILITY AT KROA AND KDAN HAD ALREADY BECOME VFR.
KLYH MAY TAKE UNTIL 20/3PM TO IMPROVE.
A BAND OF SHOWERS FROM WEST VIRGINIA INTO CENTRAL TENNESSEE WILL
MOVE ACROSS THE REGION BETWEEN 21Z/4PM AND 06Z/1AM. EXPECT THIS
PRECIPITATION TO REACH KLWB AROUND 21Z/4PM WITH OCCASIONAL MVFR
VISIBILITIES AND VFR CEILINGS JUST ABOVE 3000 FEET. THESE SHOWERS
ARE NOT EXPECTED TO REACH KLYH AND KDAN UNTIL AFTER 00Z/7PM.
A STRONG COLD FRONT WILL BE CROSSING THE AREA BETWEEN 00Z AND 12Z.
MODELS WERE ALL SIMILAR WITH THE TIMING OF THE FRONT. LINE OF
SHOWERS ALONG THE BOUNDARY MAY PRODUCE WIND GUSTS AT KLWB AND KBLF
OF 40 TO 50 KNOTS BUT CONFIDENCE IS LOW THAT OTHER TAF SITES WILL
HAVE THE POTENTIAL FOR WINDS THAT STRONG SINCE LINE IS EXPECTED TO
WEAKEN AS IT MOVES EAST.
COLD AIR ADVECTION AND TIGHT PRESSURE GRADIENTS WILL RESULT IN
GUSTY WINDS BY MONDAY AFTERNOON. EXPECT WIND GUSTS OF 25 TO
35 KNOTS. THE SKY WILL CLEAR MONDAY MORNING AS A MUCH DRIER AIR
MASS ADVECTS INTO THE REGION.
DRY HIGH PRESSURE WILL SUPPORT VFR CONDITIONS THROUGH TUESDAY
AFTERNOON...BEFORE WEDGING AGAINST THE EASTERN FACE OF THE
APPALACHIANS. MAY SEE A RETURN OF STRATUS THURSDAY MORNING AS THE
NORTHEAST FLOW WORKS ATLANTIC MOISTURE TOWARD THE BLUE RIDGE.
&&
.FIRE WEATHER...
AS OF 450 AM EST SUNDAY...
REGION STAYS IN MOIST AIR MASS TONIGHT IN ADVANCE OF A STRONG
COLD FRONT. THE PROBABILITY OF A WETTING RAIN RISES SHARPLY BY
THIS EVENING. WINDS FROM THE SOUTH AND SOUTHWEST INCREASE LATER
OVERNIGHT....ESPECIALLY AT HIGHER ELEVATIONS AHEAD OF THE FRONT.
ONCE THE FRONT COMES THROUGH EARLY MONDAY MORNING...WIND WILL SHIFT
TO THE WEST AND NORTHWEST. GUSTY WINDS ARE EXPECTED MONDAY AND
MONDAY NIGHT. BY THE TIME RELATIVE HUMIDITIES DROP BACK DOWN TO
AROUND 30 PERCENT ON TUESDAY...WIND SPEEDS WILL BE DIMINISHING.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WIND ADVISORY UNTIL 6 AM EST MONDAY FOR VAZ007-019-020-024-035.
NC...NONE.
WV...WIND ADVISORY UNTIL 6 AM EST MONDAY FOR WVZ042-043-045.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...KM
LONG TERM...RCS
AVIATION...AMS/NF
FIRE WEATHER...AMS