Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/18/13
AREA FORECAST DISCUSSION...UPDATED
NWS MELBOURNE FL
950 AM EST SAT NOV 16 2013
.DISCUSSION...
CANOPY OF MID AND HIGH CLOUD COVER CONTINUES TO STREAM ACROSS
CENTRAL FLORIDA FROM THE WEST. RUC13 SHOWS AN ELONGATED VORT IN THE
850-700 MB LAYER IN THE EASTERN GULF. HI RES VIS/IR SAT IMAGERY
SHOWS A SFC REFLECTION (NICE TWIST TO THE CLOUDS) IN THE EASTERN
GULF JUST NW OF NOAA BUOY 42003 WHICH IS MAINTAINING SHOWERS OVER
THE EASTERN GULF. ALTHOUGH NOT ANALYZED BY WPC...THERE ALSO APPEARS
TO BE TROUGH AXIS EXTENDING NE FROM THIS GULF LOW/WAVE ACROSS
CENTRAL FLORIDA AND INTO THE ATLC. WINDS HAVE TURNED LIGHT N/NE
BEHIND THIS TROUGH AXIS FROM ORLANDO NORTHWARD WHILE SE WINDS EXIST
TO THE SOUTH. NOT A SIGNIFICANT IMPACT EXCEPT TO BOATERS NORTH OF
THE CAPE SO UPDATED THE COASTAL MARINE FCST EARLIER. EXPECT A MORE
UNIFORM E/NE FLOW TO DEVELOP THIS AFTERNOON AS THE TROUGH AXIS
WEAKENS.
WEAK UPGLIDE WILL KEEP THE AREA MOSTLY CLOUDY TO CLOUDY WITH ON AND
OFF PATCHES OF LIGHT RAIN/SPRINKLES. THERE MAY BE SOME ADDITIONAL
BREAKS IN THE CLOUDS LATER IN THE DAY. HIGHS WILL REACH THE UPPER
70S ORLANDO NORTH AND LOWER 80S SOUTH.
&&
.AVIATION...
LARGE AREA OF IFR CIGS AND VSBYS EXIST ACROSS NORTH FL AND GA AND
HAVE BEEN CREEPING SOUTHWARD. BUT MID AND HIGH LEVEL OVERCAST ACROSS
OUR TERMINALS HAS KEPT THE LOW CLOUDS AT BAY. IT IS POSSIBLE SOME
LOW CLOUDS MAY REACH DAB/LEE THROUGH 16Z BUT WILL HANDLE WITH AMD IF
NECESSARY. OTHERWISE VFR WITH PREVAILING CIGS BKN-OVC100-150 AND LCL
BKN040-060 IN LIGHT PRECIP. COULD SEE SOME LOCAL MVFR VSBYS (NEAR
5SM) IN RAIN. THERE MAY BE A BETTE CHANCE FOR IFR/MVFR FOG/MIST AFT
08Z TONIGHT ACROSS THE NORTH (LEE-DAB).
&&
.MARINE...
TRICKY WIND FORECAST THIS MORNING AS A WEAK SURFACE TROUGH HAS
DROPPED INTO THE AREA. NORTH TO NORTHEAST WINDS UP TO 15 KNOTS JUST
NORTH OF THE CAPE AND SOUTH SOUTHEAST WINDS UP TO 15 KNOTS SOUTH OF
THE CAPE. THIS TROUGH APPEARS TO BE TRANSITING E/SE SO MUCH OF THE
BREVARD COASTAL WATERS MAY SEE A WIND SHIFT OUT OF THE N/NE THIS
MORNING. DO NOT THINK IT WILL MAKE IT SOUTH OF SEBASTIAN INLET. THE
TREND GOING INTO THE AFTN SHOULD BE FOR THIS TROUGH/BOUNDARY TO
DIMINISH AND ALLOW A MORE UNIFORM E/NE FLOW AROUND 10 KNOTS TO
DEVELOP ACROSS ALL THE WATERS. WILL MAINTAIN CAUTION HEADLINE FOR
THE OFFSHORE WATERS AND NEARSHORE TREASURE COAST.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 77 68 80 69 / 30 20 10 20
MCO 79 65 84 67 / 40 30 10 20
MLB 79 72 81 69 / 40 20 10 10
VRB 80 72 82 68 / 40 20 10 10
LEE 79 65 83 66 / 30 30 10 20
SFB 79 65 83 67 / 30 20 10 20
ORL 79 66 83 67 / 40 30 10 20
FPR 80 71 82 69 / 40 20 10 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
KELLY
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
920 AM EST SAT NOV 16 2013
.SYNOPSIS...
HIGH PRESSURE CENTERED OFF THE MID-ATLANTIC COAST WILL DIRECT AN
ONSHORE FLOW INTO THE FORECAST AREA THROUGH SUNDAY. AN APPROACHING
COLD FRONT WILL MOVE THROUGH THE AREA MONDAY. COLD HIGH PRESSURE
WILL FOLLOW THE FRONT AND DOMINATE THROUGH THE MIDDLE OF NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
PATCHY FOG CONTINUES THIS MORNING MAINLY AROUND THE COLUMBIA METRO
AREA...NOT WIDESPREAD AND EXPECT SLOWLY IMPROVING VISIBILITY
DURING THE MORNING.
THE NAM AND GFS SHOW RISING H5 HEIGHTS TODAY. WEAK ISENTROPIC
LIFT SHOULD SUPPORT SOME CLOUDINESS BUT MOISTURE SHOULD REMAIN
SHALLOW. ALL OF THE MOS INDICATES POPS LESS THAN 20 PERCENT. WE
WILL GET OFF TO A RELATIVELY WARM START AND WITH RISING HEIGHTS
EXPECT TEMPERATURES WILL REACH THE UPPER 60S AND LOWER 70S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
THE MODELS DISPLAY UPPER HEIGHTS BEGINNING TO FALL TONIGHT IN RESPONSE
TO A FAST MOVING TROUGH ACROSS THE UPPER MIDWEST AND DEEPENING
SURFACE LOW OVER THE GREAT LAKES. A COLD FRONT WILL PUSH EASTWARD
ACROSS THE OHIO AND TENNESSEE VALLEYS SUNDAY EVENING AND PUSH
THROUGH THE FORECAST AREA EARLY MONDAY. AHEAD OF THE FRONT...A
30- TO 40-KNOT H85 JET WILL PROVIDE ADEQUATE MOISTURE TRANSPORT
AS PRECIPITABLE WATER VALUES INCREASE TO NEAR 2 INCHES (OVER 2
STANDARD DEVIATIONS ABOVE NORMAL). WILL CONTINUE TO FORECAST AN
INCREASE IN POPS THROUGH THE AFTERNOON SUNDAY PEAKING WITH LIKELY
POPS SUNDAY NIGHT. THERE MAY BE ENOUGH INSTABILITY FOR
THUNDERSTORMS SUNDAY NIGHT. THE NAM INDICATES SURFACE-BASED LI/S
OF 0 TO -2. SHEAR WILL BE HIGH BUT THE SEVERE THREAT APPEARS
LIMITED BECAUSE OF A LACK OF SIGNIFICANT INSTABILITY. POPS SHOULD
RAPIDLY DECREASE MONDAY BEHIND THE FRONT. TEMPERATURES AHEAD OF
THE FRONT SUNDAY WILL AGAIN BE WARM AND WELL ABOVE NORMAL.
HIGH PRESSURE WILL BUILD INTO THE AREA WITH NORTHERLY WINDS IN THE
WAKE OF THE COLD FRONT OFF THE COAST AS THE UPPER FLOW BECOMES
WESTERLY. THE COOLER AIR WILL BE LAGGING WELL BEHIND THE FRONT AND
MONDAY WILL LIKELY FEATURE WELL ABOVE NORMAL TEMPERATURES IN THE
70S AFTER A VERY WARM SUNDAY NIGHT WHERE LOW TEMPERATURES ARE
EXPECTED TO BE 15 TO 20 DEGREES ABOVE NORMAL BECAUSE OF CLOUDINESS
AND MIXING.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
WE HAVE REASONABLY HIGH CONFIDENCE IN A DRY AND FAIR WEATHER
PATTERN DURING THE MEDIUM-RANGE PERIOD WITH GOOD MODEL AGREEMENT.
THE UPPER PATTERN TUESDAY FEATURES A TROUGH PUSHING OFF THE MID-
ATLANTIC COAST WITH WEST TO NORTHWESTERLY FLOW OVER THE FORECAST
AREA. GENERALLY DRY ZONAL FLOW EXPECTED WEDNESDAY THROUGH FRIDAY.
SURFACE HIGH PRESSURE WILL BUILD OVER THE REGION TUESDAY IN THE
WAKE OF THE FRONTAL PASSAGE MONDAY. COOL H85 TEMPERATURES WILL
SETTLE OVER THE FORECAST AREA THROUGH MIDWEEK AND DESPITE EXPECTED
SUNSHINE...EXPECT TEMPERATURES TO REMAIN SLIGHTLY BELOW NORMAL.
SHORTWAVE RIDGING DEVELOPS OVER THE SOUTHEAST BY FRIDAY IN
RESPONSE TO A SHARPLY DIGGING UPSTREAM TROUGH BUT PERSISTENT
NORTHEASTERLY SURFACE FLOW WILL CONTINUE TO LIMIT WARMING.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
LATEST HRRR GUIDANCE SUGGESTING LOW STRATUS AND OR FOG WILL
CONTINUE ACROSS THE AREA THROUGH LATE MORNING...
IFR/LIFR CONDITIONS EXPECTED TO CONTINUE ACROSS MUCH OF THE
FORECAST AREA UNTIL AROUND 15Z-16Z THIS MORNING THEN SLOW IMPROVEMENT.
BY 18Z EXPECT VFR ALL TAF SITES WITH A LIGHT EASTERLY WIND.
EXTENDED AVIATION OUTLOOK...INCREASING CONFIDENCE IN RESTRICTIONS
SUNDAY MORNING INTO MONDAY. A COLD FRONT IS FORECAST TO CROSS THE
AREA EARLY MONDAY. BREEZY CONDITIONS POSSIBLE TUESDAY AND WEDNESDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
243 PM CST SAT NOV 16 2013
.DISCUSSION...
1230 PM CST
ONLY SMALL CHANGES MADE TO THIS AFTERNOON FORECAST. SHOWER
COVERAGE WILL FURTHER INCREASE AHEAD OF THE WELL-DEFINED SHORT
WAVE TROUGH LIFTING NORTHEAST FROM THE NE/IA BORDER. THE MOISTURE
TRANSPORT NOSE ALONG WITH ELEVATED STEEP LAPSE RATES SEEN ON 12Z
REGIONAL SOUNDINGS WILL CONTINUE TO ADVECT OVER THE AREA
SUPPORTING AND REPLENISHING THIS ACTIVITY INTO EARLY EVE. SEVERE
POTENTIAL REMAINS VERY LOW WITH THIS. TEMPERATURES SHOULD CONTINUE
TO WARM ESPECIALLY OUTSIDE OF THE SHOWERS...JUST SIMPLY BY PURE
ADVECTION.
PRONOUNCED REGIONAL SEVERE THREAT CONTINUES FOR LATE TONIGHT INTO
SUNDAY AFTERNOON. NEW SPC MODERATE RISK DOES INCLUDE A LARGER
PORTION OF THE FORECAST AREA...INCLUDING ALL OF CHICAGOLAND.
UPDATED DISCUSSION ON THIS WILL BE POSTED BY 300 PM.
MTF
//PREV DISCUSSION...
815 AM CST
FORECAST UPDATED TO ADD DRIZZLE IN THROUGH THIS MORNING.
THE LOW-LEVEL MOISTURE SURGE CONTINUES TO RETURN OVER THE AREA.
ISENTROPIC ASCENT ON THE RAP ANALYSIS OF 285K AND 290K SURFACES
HAS RAPIDLY SATURATED AND LOOKS TO BE THE ROOT OF THIS. EVEN ON
THE 12Z ILX RAOB...THE PROFILE WAS VERY SUGGESTIVE OF DRIZZLE.
THIS COULD CONTINUE INTO THIS AFTERNOON BASED ON THE EXTENT OF
UPSTREAM OBS ACROSS CENTRAL AND SOUTHERN IL. SOUTH WINDS CONTINUE
TO BRING WARM AIR ADVECTION SO TEMPERATURES WILL INCH UPWARD. THE
CHANCE FOR TRUE SHOWERS AND POSSIBLY SOME STORMS TODAY STILL LOOKS
TO ARRIVE WITH A SHORT WAVE ACROSS THE WESTERN FORECAST AREA BY
EARLY AFTERNOON AND SPREADING EAST FROM THERE.
MTF
//PREV DISCUSSION...
333 AM...FORECAST FOCUS REMAINS POTENTIAL SEVERE WEATHER OUTBREAK
ACROSS THE SOUTHERN LAKES AND OHIO VALLEY ON SUNDAY.
IN THE SHORT TERM...LOW CLOUDS HAVE STREAMED NORTH ACROSS THE AREA
SIGNALING THE BEGINNING OF A SURGE OF LOW LEVEL MOISTURE.
DEWPOINTS SLOWLY CREEPING INTO THE LOWER 40S EARLY THIS MORNING
WILL CONTINUE TO RISE INTO THE LOWER/MID 50S THIS AFTERNOON...UPPER
50S TONIGHT AND LIKELY POOL IN THE LOWER TO PERHAPS MID 60S JUST
AHEAD OF THE COLD FRONT SUNDAY MORNING.
LOW PRESSURE OVER NEBRASKA WILL LIFT NORTH TO MINNESOTA BY THIS
EVENING AND AS IT DOES...AN UPPER LEVEL WAVE WILL MOVE ACROSS THE
AREA THIS AFTERNOON INTO THIS EVENING. MUCH OF THE EASTERN HALF OR
TWO THIRDS WILL LIKELY REMAIN DRY THIS MORNING WITH PRECIP
SPREADING ACROSS THE WESTERN CWA BY LATE MORNING. HAVE INCLUDED
JUST A CHANCE OF THUNDERSTORMS WITH THE STRONGER/CONVECTIVE
ELEMENTS BUT CONFIDENCE REGARDING HOW WIDESPREAD LIGHTNING/THUNDER
WILL BECOME IS SOMEWHAT LOW AND THUNDER COVERAGE MAY NEED TO BE
INCREASED BASED ON SHORT TERM TRENDS ONCE PRECIP DEVELOPS/ARRIVES.
THIS ACTIVITY SHOULD MOVE NORTHEAST OF THE AREA BY MID/LATE EVENING
WITH A POSSIBLE LULL IN ACTIVITY INTO THE EARLY MORNING HOURS. NOT
EXPECTING ANY OF THE THUNDERSTORMS DURING THIS FIRST WAVE TO BE
SEVERE. SOME COULD PRODUCE STRONG/GUSTY WINDS AS WELL AS HEAVY
RAIN. THOUGH STORM MOTION SHOULD BE SUFFICIENTLY FAST TO PREVENT A
LONG DURATION HEAVY RAIN IN ANY ONE LOCATION. RAINFALL AMOUNTS
WITH THIS WAVE APPEAR TO BE IN THE 0.5 TO 0.75 RANGE.
DESPITE MAINLY CLOUDY SKIES TODAY AND THEN PRECIP THIS
AFTERNOON...WITH THE NOTED SURGE IN LOW LEVEL MOISTURE...TEMPS
WILL CONTINUE TO CLIMB THROUGH THE DAY WITH CURRENT TEMPS ALREADY
IN THE LOWER 50S ACROSS SOUTHERN IL. THUS...HIGHS IN THE UPPER 50S
TO LOWER 60S LOOK ON TRACK AND MUCH OF THE SOUTHERN THIRD/HALF OF
THE CWA MAY NOT SEE PRECIP UNTIL LATE THIS AFTERNOON AND IF ANY
BREAKS DEVELOP...THIS WILL AID TEMPS FURTHER. AS PRECIP ENDS THIS
EVENING...POSSIBLE FOR SOME LOCATIONS...ESPECIALLY NORTHERN
CWA...TO CONTINUE TO WARM WITH HIGHS BEING REACHED IN THE EVENING.
A SECOND LOW THEN DEVELOPS OVER EASTERN COLORADO TONIGHT AND
QUICKLY SHIFTS EAST TO IOWA BY SUNDAY MORNING...THEN RAPIDLY
DEEPENS AS IT ABSORBS THE FIRST LOW OVER MINNESOTA...AND REACHES
LAKE SUPERIOR BY SUNDAY EVENING. A STRONG COLD FRONT WILL RACE
ACROSS THE CWA FROM MID/LATE SUNDAY MORNING THROUGH EARLY/MID
SUNDAY AFTERNOON. ANOTHER WAVE OF THUNDERSTORMS IS POSSIBLE IN THE
EARLY MORNING HOURS OF SUNDAY AHEAD OF THIS SECOND LOW...
DEVELOPING OVER EASTERN IOWA AND NORTHWEST IL THEN MOVING INTO
SOUTHERN WI...MOSTLY LIKELY BY SUNRISE. AT THE SAME TIME...
ADDITIONAL THUNDERSTORMS COULD BE DEVELOPING AHEAD OF THE COLD
FRONT ACROSS PARTS OF IOWA/MISSOURI. ANY OF THESE THUNDERSTORMS
OVERNIGHT INTO EARLY SUNDAY MORNING COULD BECOME SEVERE. BUT TO
WHAT EXTENT AND HOW WIDESPREAD ANY SEVERE WEATHER WOULD BECOME IS
UNCERTAIN. HOWEVER...WITH SUCH WARM/MOIST LOW LEVELS...A DEEPENING
SURFACE LOW AND WHAT COULD END UP BEING A WARM FRONTAL BOUNDARY
ACROSS THE NORTHERN CWA...THE THREAT OF A TORNADO WITH ANY STRONG
STORMS CAN/T BE RULED OUT.
ANOTHER BRIEF LULL IS EXPECTED SUNDAY MORNING BEFORE WHAT APPEARS
LIKE IT COULD BE THE BEGINNING OF A WIDESPREAD SEVERE WEATHER
OUTBREAK DEVELOPS. WINDS THROUGH THE ENTIRE COLUMN REMAIN VERY
IMPRESSIVE WITH 50 KNOTS AS LOW AS 900MB SUNDAY MORNING. AS
NOTED...WHILE THE WARM/MOIST CONDITIONS WILL HELP/AID STORMS
STAYING SURFACE BASED...EXPECT QUITE A BIT OF CLOUD COVER...AND
WHILE HAVE TRIED TO SHOW SOME PARTLY/MOSTLY CLOUDY CONDITIONS AT
LEAST ACROSS THE SOUTHEAST CWA SUNDAY MORNING...ITS POSSIBLE
OVERCAST CONDITIONS WILL PERSIST UNTIL FROPA. ADDITIONAL
UNCERTAINTY REMAINS WITH WHERE/WHEN THUNDERSTORMS WILL DEVELOP...
JUST WEST OF THE CWA...OVER THE CWA...EASTERN CWA/NORTHWEST
INDIANA. ENTIRE CWA IS NOW INCLUDED IN SLIGHT RISK PER THIS
MORNING/S SPC DAY2 OUTLOOK WITH MODERATE RISK EAST OF THE
I-55/I-57 CORRIDOR. POTENTIAL IS CERTAINLY HIGHER OVER THE EASTERN
CWA BUT EVEN FROM THIS DISTANCE WILL BE INCLUDING SEVERE
MENTION/DAMAGING WINDS IN THE ZONES/GRIDS. THUNDERSTORMS WILL BE
ENDING FROM WEST TO EAST DURING THE MID/LATE AFTERNOON AND ALSO
ATTEMPTED TO INCLUDE THIS TIMING IN THE GRIDS. THE THREAT OF A
TORNADO OR TWO WILL REMAIN SUNDAY BUT DAMAGING WINDS APPEAR TO BE
THE PRIMARY SEVERE WEATHER THREAT. DESPITE PRECIPITABLE WATER
VALUES ONLY AROUND AN INCH...EXPECT VERY EFFICIENT RAIN PRODUCTION
WITH ANOTHER 0.5-0.75 INCHES POSSIBLE...ALTHOUGH PERHAPS MORE
LOCALIZED DEPENDING ON CONVECTIVE COVERAGE.
STRONG WINDS FROM THE SOUTH WILL DEVELOP TODAY WITH GUSTS INTO THE
30-35 MPH RANGE POSSIBLE. STILL APPEARS THERE COULD BE A 3-6 HOUR
WINDOW THIS EVENING OF GUSTS 40+ MPH BEFORE WINDS DIMINISH SOME
OVERNIGHT...WHILE CLOSE TO WIND ADVISORY CRITERIA...NOT SURE IT
WILL BE REACHED AND NO HEADLINES THROUGH TONIGHT. BY SUNDAY...
LOW LEVEL WINDS ARE WELL INTO ADVISORY CRITERIA AND SOME OF THIS
WILL LIKELY MIX TO THE SURFACE ESPECIALLY JUST BEHIND THE STORMS/
COLD FRONT AS COLD ADVECTION IS AIDED BY LARGE PRESSURE RISES.
THIS IS THIRD PERIOD AND A BIT EARLY FOR AN ADVISORY AND LATER
SHIFTS WILL NEED TO ASSESS WIND POTENTIAL/HEADLINES FOR SUNDAY.
HAVE CONTINUED INCREASING HIGH TEMPS FOR SUNDAY WITH MID 60S NORTH
TO UPPER 60S FROM I-55 SOUTH AND ITS QUITE POSSIBLE SOME AREAS MAY
SEE TEMPS TAG 70 AHEAD OF THE FRONT...ESPECIALLY WITH ANY BREAKS
IN THE OVERCAST AS 850MB TEMPS ARE NOW EXPECTED TO BE IN THE +12C
TO +15C RANGE.
WRAP AROUND SHOWERS WILL BE POSSIBLE SUNDAY EVENING BUT SHOULD BE
ENDING FAIRLY QUICKLY WITH CLEARING SKIES OVERNIGHT AS HIGH
PRESSURE BUILDS INTO THE REGION MONDAY AFTERNOON/MONDAY NIGHT AND
THIS HIGH IS MOVING FASTER THAN PREVIOUS MODELS HAD SUGGESTED.
WHILE IT WILL TURN MUCH COLDER MONDAY NIGHT WITH LOWS IN THE 30S...
MONDAY MAY END UP BEING MAINLY SUNNY WITH DIMINISHING WINDS IN THE
AFTERNOON AND TEMPS REBOUNDING BACK INTO THE MID 40S. STILL WILL
FEEL MUCH COLDER COMPARED TO SUNDAY...BUT THE TREND IS SLIGHTLY
WARMER.
HAVE CONTINUED THE WARMING TREND TUESDAY THROUGH THURSDAY AS WINDS
TURN SOUTHERLY SOONER ON THE BACK SIDE OF THE DEPARTING HIGH. ALSO
NOW APPEARS THE CHANCE OF SHOWERS WILL ARRIVE SOONER...PERHAPS AS
EARLY AS LATE WEDNESDAY BUT CERTAINLY WEDNESDAY NIGHT INTO
THURSDAY. WARMING TEMPS DURING THIS PERIOD WITH SOUTHERLY FLOW
SHOULD KEEP PRECIP MAINLY LIQUID. A COLD FRONT THEN MOVES SOUTH
THURSDAY NIGHT AND FRIDAY WITH THE ECMWF MUCH COLDER THAN THE GFS
AND HAVE LOWERED TEMPS A FEW DEGREES DURING THIS TIME PERIOD AND
WHILE ITS STILL SEVERAL DAYS AWAY...POTENTIAL FOR SOME FROZEN
PRECIP EXISTS LATER FRIDAY/FRIDAY NIGHT...DEPENDING ON SPEED OF
FRONT AND END TIME OF PRECIP. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* IFR CIGS THIS AFTERNOON AND POTENTIALLY THROUGH TONIGHT.
* SHRA WITH GRADUALLY INCREASING CHANCES FOR THUNDER THROUGH
EARLY EVE.
* SOUTH WINDS GUSTING TO AROUND 30 KT AT TIMES THROUGH THIS
EVE...THEN TURNING SOUTHWEST AND BECOMING EVEN MORE GUSTY ON
SUNDAY AFTERNOON.
* LOW LEVEL WIND SHEAR POSSIBLE AS WINDS NEAR 1500 FT INCREASE TO
50 KT OR STRONGER.
* TSRA CHANCES INCREASING AROUND DAYBREAK WITH GUSTY SEVERE STORM
POTENTIAL THIS MORNING AND EARLY AFTERNOON.
//DISCUSSION...UPDATED 18Z...
INITIAL LOW PRESSURE MOVING NORTHWARD INTO MN CONTINUES TO
INCREASE SOUTHERLY WINDS ACROSS THE AREA...AND AS AN EVEN MORE
POTENT LOW PRESSURE DEVELOPS ON SUNDAY THE SOUTH WINDS WILL REALLY
RAMP UP. SOUTHERLY GUSTS TO 30 KT OR EVEN SLIGHTLY HIGHER MAY BE
SEEN THIS AFTERNOON. SHOWERS WITH EMBEDDED SCATTERED THUNDER WILL
INCREASE IN COVERAGE THROUGH LATE AFTERNOON WITH THIS INITIAL LOW
PRESSURE. THERE PROBABLY WILL BE A SLIGHT DIMINISHING IN COVERAGE
THEN THROUGH THE MID TO LATE EVE AS THIS INITIAL MOISTURE SURGE
PASSES. BUT AS INFLUENCE OF THE SECOND WEATHER SYSTEM BEGINS TO
OVERSPREAD THE AREA...SCATTERED STORMS ARE LIKELY TO DEVELOP
OVERNIGHT INTO SUNDAY MORNING THAT WILL ADVANCING NORTHWARD.
THUNDER POTENTIAL WILL MAXIMIZE DURING THE LATE MORNING THROUGH
MID AFTERNOON FOR THE CHICAGO AREA TAF SITES. SOME OF THESE COULD
BE SEVERE GIVEN THE POTENT WIND FIELD AND SURPRISING INSTABILITY
WITHIN THIS SYSTEM FOR THIS TIME OF YEAR. WINDS AROUND AND UNDER
THESE STORMS WILL BE ESPECIALLY GUSTY...BUT EVEN THE PREVAILING
WINDS WILL BE VERY GUSTY BY AFTERNOON...WITH GUSTS OF 35KT+.
MTF
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM TO HIGH CONFIDENCE IN IFR CIGS THROUGH EARLY EVE.
* HIGH CONFIDENCE IN SHRA THROUGH EARLY THIS EVE.
* HIGH CONFIDENCE IN WIND DIRECTION...SPEEDS...AND GUSTS THROUGH
18Z SUNDAY...MEDIUM CONFIDENCE AFTER.
* HIGH CONFIDENCE IN 50-60KT SW WINDS IN THE 1500-3000FT LAYER
THIS EVE.
* MEDIUM CONFIDENCE IN TSRA TIMING THROUGHOUT THE TAF. HIGH
CONFIDENCE THAT IF STRONG TO SEVERE STORMS OCCUR AT THE AIRPORTS
THEY WOULD BE BE AFTER 10Z...AND MOST PROBABLE 17Z-21Z.
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...BREEZY WEST WINDS DIMINISHING LATE.
MONDAY THROUGH WEDNESDAY...VFR.
THURSDAY AND FRIDAY...SLIGHT CHANCE SHRA DURING THE DAY AND RASN
AT NIGHT. MAINLY VFR.
MDB
&&
.MARINE...
215 PM CST
A STRONG STORM SYSTEM WILL IMPACT THE GREAT LAKES REGION OVER THE
WEEKEND BRINGING PERIODS OF GALES WITH STORM FORCE WINDS A
POSSIBILITY ON THE BACK END OF THE SYSTEM. BROAD AREA OF LOW
PRESSURE IS BEGINNING TO CONSOLIDATE OVER THE NORTHERN PLAINS
TODAY...BUT WILL SIGNIFICANTLY DEEPEN OVER WISCONSIN EARLY SUNDAY
AFTERNOON...THEN CONTINUE TO DEEPEN AS IT MOVES ACROSS NORTHERN LAKE
MICHIGAN SUNDAY EVENING. SOUTHERLY GALES WILL CONTINUE THROUGH THE
OVERNIGHT HOURS INTO EARLY SUNDAY. THESE WINDS WILL TRANSPORT MOIST
AIR NORTH OVER THE WATERS WHICH IS EXPECTED TO LEAD TO AREAS OF FOG
DEVELOPMENT. IT IS UNCERTAIN HOW WIDESPREAD OR DENSE THE FOG WILL
BE...BUT A FOG ADVISORY IS NOT OUT OF THE REALM OF POSSIBILITY.
WINDS ARE EXPECTED TO EASE SLIGHTLY BELOW GALES DURING PORTIONS OF
THE DAY SUNDAY...ESPECIALLY THE NORTHERN HALF OF THE LAKE WHERE THE
GRADIENT WILL WEAKEN NEAR THE LOW CENTER. AFTER THE LOW AND
ATTENDANT COLD FRONT PUSH EAST OF THE LAKE SUNDAY EVENING...WINDS
WILL TURN WESTERLY AND QUICKLY RAMP BACK UP TO STRONG GALES OF 40 TO
45 KT...WITH OCCASIONAL STORM FORCE GUSTS STILL A POSSIBILITY. WINDS
WILL SLOWLY TAPER MONDAY AS A RIDGE OF HIGH PRESSURE BUILDS ACROSS
THE MISSISSIPPI VALLEY...AND SHOULD DROP BELOW GALES BY MID
AFTERNOON. WINDS BACK TO THE SOUTHWEST ON TUESDAY AS LOW PRESSURE
MOVES EAST ACROSS THE CANADIAN PRAIRIES. SOUTHERLY GALES MAY BE
POSSIBLE AGAIN ON WEDNESDAY AHEAD OF AN APPROACHING COLD FRONT.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WIND ADVISORY...ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-
ILZ021-ILZ022-ILZ023-ILZ032-ILZ033-ILZ039...10 AM SUNDAY TO
8 PM SUNDAY.
IN...WIND ADVISORY...INZ001-INZ002-INZ010-INZ011-INZ019...10 AM
SUNDAY TO 8 PM SUNDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY.
GALE WARNING...NEARSHORE WATERS UNTIL 4
AM MONDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
216 PM CST SAT NOV 16 2013
.DISCUSSION...
1230 PM CST
ONLY SMALL CHANGES MADE TO THIS AFTERNOON FORECAST. SHOWER
COVERAGE WILL FURTHER INCREASE AHEAD OF THE WELL-DEFINED SHORT
WAVE TROUGH LIFTING NORTHEAST FROM THE NE/IA BORDER. THE MOISTURE
TRANSPORT NOSE ALONG WITH ELEVATED STEEP LAPSE RATES SEEN ON 12Z
REGIONAL SOUNDINGS WILL CONTINUE TO ADVECT OVER THE AREA
SUPPORTING AND REPLENISHING THIS ACTIVITY INTO EARLY EVE. SEVERE
POTENTIAL REMAINS VERY LOW WITH THIS. TEMPERATURES SHOULD CONTINUE
TO WARM ESPECIALLY OUTSIDE OF THE SHOWERS...JUST SIMPLY BY PURE
ADVECTION.
PRONOUNCED REGIONAL SEVERE THREAT CONTINUES FOR LATE TONIGHT INTO
SUNDAY AFTERNOON. NEW SPC MODERATE RISK DOES INCLUDE A LARGER
PORTION OF THE FORECAST AREA...INCLUDING ALL OF CHICAGOLAND.
UPDATED DISCUSSION ON THIS WILL BE POSTED BY 300 PM.
MTF
//PREV DISCUSSION...
815 AM CST
FORECAST UPDATED TO ADD DRIZZLE IN THROUGH THIS MORNING.
THE LOW-LEVEL MOISTURE SURGE CONTINUES TO RETURN OVER THE AREA.
ISENTROPIC ASCENT ON THE RAP ANALYSIS OF 285K AND 290K SURFACES
HAS RAPIDLY SATURATED AND LOOKS TO BE THE ROOT OF THIS. EVEN ON
THE 12Z ILX RAOB...THE PROFILE WAS VERY SUGGESTIVE OF DRIZZLE.
THIS COULD CONTINUE INTO THIS AFTERNOON BASED ON THE EXTENT OF
UPSTREAM OBS ACROSS CENTRAL AND SOUTHERN IL. SOUTH WINDS CONTINUE
TO BRING WARM AIR ADVECTION SO TEMPERATURES WILL INCH UPWARD. THE
CHANCE FOR TRUE SHOWERS AND POSSIBLY SOME STORMS TODAY STILL LOOKS
TO ARRIVE WITH A SHORT WAVE ACROSS THE WESTERN FORECAST AREA BY
EARLY AFTERNOON AND SPREADING EAST FROM THERE.
MTF
//PREV DISCUSSION...
333 AM...FORECAST FOCUS REMAINS POTENTIAL SEVERE WEATHER OUTBREAK
ACROSS THE SOUTHERN LAKES AND OHIO VALLEY ON SUNDAY.
IN THE SHORT TERM...LOW CLOUDS HAVE STREAMED NORTH ACROSS THE AREA
SIGNALING THE BEGINNING OF A SURGE OF LOW LEVEL MOISTURE.
DEWPOINTS SLOWLY CREEPING INTO THE LOWER 40S EARLY THIS MORNING
WILL CONTINUE TO RISE INTO THE LOWER/MID 50S THIS AFTERNOON...UPPER
50S TONIGHT AND LIKELY POOL IN THE LOWER TO PERHAPS MID 60S JUST
AHEAD OF THE COLD FRONT SUNDAY MORNING.
LOW PRESSURE OVER NEBRASKA WILL LIFT NORTH TO MINNESOTA BY THIS
EVENING AND AS IT DOES...AN UPPER LEVEL WAVE WILL MOVE ACROSS THE
AREA THIS AFTERNOON INTO THIS EVENING. MUCH OF THE EASTERN HALF OR
TWO THIRDS WILL LIKELY REMAIN DRY THIS MORNING WITH PRECIP
SPREADING ACROSS THE WESTERN CWA BY LATE MORNING. HAVE INCLUDED
JUST A CHANCE OF THUNDERSTORMS WITH THE STRONGER/CONVECTIVE
ELEMENTS BUT CONFIDENCE REGARDING HOW WIDESPREAD LIGHTNING/THUNDER
WILL BECOME IS SOMEWHAT LOW AND THUNDER COVERAGE MAY NEED TO BE
INCREASED BASED ON SHORT TERM TRENDS ONCE PRECIP DEVELOPS/ARRIVES.
THIS ACTIVITY SHOULD MOVE NORTHEAST OF THE AREA BY MID/LATE EVENING
WITH A POSSIBLE LULL IN ACTIVITY INTO THE EARLY MORNING HOURS. NOT
EXPECTING ANY OF THE THUNDERSTORMS DURING THIS FIRST WAVE TO BE
SEVERE. SOME COULD PRODUCE STRONG/GUSTY WINDS AS WELL AS HEAVY
RAIN. THOUGH STORM MOTION SHOULD BE SUFFICIENTLY FAST TO PREVENT A
LONG DURATION HEAVY RAIN IN ANY ONE LOCATION. RAINFALL AMOUNTS
WITH THIS WAVE APPEAR TO BE IN THE 0.5 TO 0.75 RANGE.
DESPITE MAINLY CLOUDY SKIES TODAY AND THEN PRECIP THIS
AFTERNOON...WITH THE NOTED SURGE IN LOW LEVEL MOISTURE...TEMPS
WILL CONTINUE TO CLIMB THROUGH THE DAY WITH CURRENT TEMPS ALREADY
IN THE LOWER 50S ACROSS SOUTHERN IL. THUS...HIGHS IN THE UPPER 50S
TO LOWER 60S LOOK ON TRACK AND MUCH OF THE SOUTHERN THIRD/HALF OF
THE CWA MAY NOT SEE PRECIP UNTIL LATE THIS AFTERNOON AND IF ANY
BREAKS DEVELOP...THIS WILL AID TEMPS FURTHER. AS PRECIP ENDS THIS
EVENING...POSSIBLE FOR SOME LOCATIONS...ESPECIALLY NORTHERN
CWA...TO CONTINUE TO WARM WITH HIGHS BEING REACHED IN THE EVENING.
A SECOND LOW THEN DEVELOPS OVER EASTERN COLORADO TONIGHT AND
QUICKLY SHIFTS EAST TO IOWA BY SUNDAY MORNING...THEN RAPIDLY
DEEPENS AS IT ABSORBS THE FIRST LOW OVER MINNESOTA...AND REACHES
LAKE SUPERIOR BY SUNDAY EVENING. A STRONG COLD FRONT WILL RACE
ACROSS THE CWA FROM MID/LATE SUNDAY MORNING THROUGH EARLY/MID
SUNDAY AFTERNOON. ANOTHER WAVE OF THUNDERSTORMS IS POSSIBLE IN THE
EARLY MORNING HOURS OF SUNDAY AHEAD OF THIS SECOND LOW...
DEVELOPING OVER EASTERN IOWA AND NORTHWEST IL THEN MOVING INTO
SOUTHERN WI...MOSTLY LIKELY BY SUNRISE. AT THE SAME TIME...
ADDITIONAL THUNDERSTORMS COULD BE DEVELOPING AHEAD OF THE COLD
FRONT ACROSS PARTS OF IOWA/MISSOURI. ANY OF THESE THUNDERSTORMS
OVERNIGHT INTO EARLY SUNDAY MORNING COULD BECOME SEVERE. BUT TO
WHAT EXTENT AND HOW WIDESPREAD ANY SEVERE WEATHER WOULD BECOME IS
UNCERTAIN. HOWEVER...WITH SUCH WARM/MOIST LOW LEVELS...A DEEPENING
SURFACE LOW AND WHAT COULD END UP BEING A WARM FRONTAL BOUNDARY
ACROSS THE NORTHERN CWA...THE THREAT OF A TORNADO WITH ANY STRONG
STORMS CAN/T BE RULED OUT.
ANOTHER BRIEF LULL IS EXPECTED SUNDAY MORNING BEFORE WHAT APPEARS
LIKE IT COULD BE THE BEGINNING OF A WIDESPREAD SEVERE WEATHER
OUTBREAK DEVELOPS. WINDS THROUGH THE ENTIRE COLUMN REMAIN VERY
IMPRESSIVE WITH 50 KNOTS AS LOW AS 900MB SUNDAY MORNING. AS
NOTED...WHILE THE WARM/MOIST CONDITIONS WILL HELP/AID STORMS
STAYING SURFACE BASED...EXPECT QUITE A BIT OF CLOUD COVER...AND
WHILE HAVE TRIED TO SHOW SOME PARTLY/MOSTLY CLOUDY CONDITIONS AT
LEAST ACROSS THE SOUTHEAST CWA SUNDAY MORNING...ITS POSSIBLE
OVERCAST CONDITIONS WILL PERSIST UNTIL FROPA. ADDITIONAL
UNCERTAINTY REMAINS WITH WHERE/WHEN THUNDERSTORMS WILL DEVELOP...
JUST WEST OF THE CWA...OVER THE CWA...EASTERN CWA/NORTHWEST
INDIANA. ENTIRE CWA IS NOW INCLUDED IN SLIGHT RISK PER THIS
MORNING/S SPC DAY2 OUTLOOK WITH MODERATE RISK EAST OF THE
I-55/I-57 CORRIDOR. POTENTIAL IS CERTAINLY HIGHER OVER THE EASTERN
CWA BUT EVEN FROM THIS DISTANCE WILL BE INCLUDING SEVERE
MENTION/DAMAGING WINDS IN THE ZONES/GRIDS. THUNDERSTORMS WILL BE
ENDING FROM WEST TO EAST DURING THE MID/LATE AFTERNOON AND ALSO
ATTEMPTED TO INCLUDE THIS TIMING IN THE GRIDS. THE THREAT OF A
TORNADO OR TWO WILL REMAIN SUNDAY BUT DAMAGING WINDS APPEAR TO BE
THE PRIMARY SEVERE WEATHER THREAT. DESPITE PRECIPITABLE WATER
VALUES ONLY AROUND AN INCH...EXPECT VERY EFFICIENT RAIN PRODUCTION
WITH ANOTHER 0.5-0.75 INCHES POSSIBLE...ALTHOUGH PERHAPS MORE
LOCALIZED DEPENDING ON CONVECTIVE COVERAGE.
STRONG WINDS FROM THE SOUTH WILL DEVELOP TODAY WITH GUSTS INTO THE
30-35 MPH RANGE POSSIBLE. STILL APPEARS THERE COULD BE A 3-6 HOUR
WINDOW THIS EVENING OF GUSTS 40+ MPH BEFORE WINDS DIMINISH SOME
OVERNIGHT...WHILE CLOSE TO WIND ADVISORY CRITERIA...NOT SURE IT
WILL BE REACHED AND NO HEADLINES THROUGH TONIGHT. BY SUNDAY...
LOW LEVEL WINDS ARE WELL INTO ADVISORY CRITERIA AND SOME OF THIS
WILL LIKELY MIX TO THE SURFACE ESPECIALLY JUST BEHIND THE STORMS/
COLD FRONT AS COLD ADVECTION IS AIDED BY LARGE PRESSURE RISES.
THIS IS THIRD PERIOD AND A BIT EARLY FOR AN ADVISORY AND LATER
SHIFTS WILL NEED TO ASSESS WIND POTENTIAL/HEADLINES FOR SUNDAY.
HAVE CONTINUED INCREASING HIGH TEMPS FOR SUNDAY WITH MID 60S NORTH
TO UPPER 60S FROM I-55 SOUTH AND ITS QUITE POSSIBLE SOME AREAS MAY
SEE TEMPS TAG 70 AHEAD OF THE FRONT...ESPECIALLY WITH ANY BREAKS
IN THE OVERCAST AS 850MB TEMPS ARE NOW EXPECTED TO BE IN THE +12C
TO +15C RANGE.
WRAP AROUND SHOWERS WILL BE POSSIBLE SUNDAY EVENING BUT SHOULD BE
ENDING FAIRLY QUICKLY WITH CLEARING SKIES OVERNIGHT AS HIGH
PRESSURE BUILDS INTO THE REGION MONDAY AFTERNOON/MONDAY NIGHT AND
THIS HIGH IS MOVING FASTER THAN PREVIOUS MODELS HAD SUGGESTED.
WHILE IT WILL TURN MUCH COLDER MONDAY NIGHT WITH LOWS IN THE 30S...
MONDAY MAY END UP BEING MAINLY SUNNY WITH DIMINISHING WINDS IN THE
AFTERNOON AND TEMPS REBOUNDING BACK INTO THE MID 40S. STILL WILL
FEEL MUCH COLDER COMPARED TO SUNDAY...BUT THE TREND IS SLIGHTLY
WARMER.
HAVE CONTINUED THE WARMING TREND TUESDAY THROUGH THURSDAY AS WINDS
TURN SOUTHERLY SOONER ON THE BACK SIDE OF THE DEPARTING HIGH. ALSO
NOW APPEARS THE CHANCE OF SHOWERS WILL ARRIVE SOONER...PERHAPS AS
EARLY AS LATE WEDNESDAY BUT CERTAINLY WEDNESDAY NIGHT INTO
THURSDAY. WARMING TEMPS DURING THIS PERIOD WITH SOUTHERLY FLOW
SHOULD KEEP PRECIP MAINLY LIQUID. A COLD FRONT THEN MOVES SOUTH
THURSDAY NIGHT AND FRIDAY WITH THE ECMWF MUCH COLDER THAN THE GFS
AND HAVE LOWERED TEMPS A FEW DEGREES DURING THIS TIME PERIOD AND
WHILE ITS STILL SEVERAL DAYS AWAY...POTENTIAL FOR SOME FROZEN
PRECIP EXISTS LATER FRIDAY/FRIDAY NIGHT...DEPENDING ON SPEED OF
FRONT AND END TIME OF PRECIP. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* IFR CIGS THIS AFTERNOON AND POTENTIALLY THROUGH TONIGHT.
* SHRA WITH GRADUALLY INCREASING CHANCES FOR THUNDER THROUGH
EARLY EVE.
* SOUTH WINDS GUSTING TO AROUND 30 KT AT TIMES THROUGH THIS
EVE...THEN TURNING SOUTHWEST AND BECOMING EVEN MORE GUSTY ON
SUNDAY AFTERNOON.
* LOW LEVEL WIND SHEAR POSSIBLE AS WINDS NEAR 1500 FT INCREASE TO
50 KT OR STRONGER.
* TSRA CHANCES INCREASING AROUND DAYBREAK WITH GUSTY SEVERE STORM
POTENTIAL THIS MORNING AND EARLY AFTERNOON.
//DISCUSSION...UPDATED 18Z...
INITIAL LOW PRESSURE MOVING NORTHWARD INTO MN CONTINUES TO
INCREASE SOUTHERLY WINDS ACROSS THE AREA...AND AS AN EVEN MORE
POTENT LOW PRESSURE DEVELOPS ON SUNDAY THE SOUTH WINDS WILL REALLY
RAMP UP. SOUTHERLY GUSTS TO 30 KT OR EVEN SLIGHTLY HIGHER MAY BE
SEEN THIS AFTERNOON. SHOWERS WITH EMBEDDED SCATTERED THUNDER WILL
INCREASE IN COVERAGE THROUGH LATE AFTERNOON WITH THIS INITIAL LOW
PRESSURE. THERE PROBABLY WILL BE A SLIGHT DIMINISHING IN COVERAGE
THEN THROUGH THE MID TO LATE EVE AS THIS INITIAL MOISTURE SURGE
PASSES. BUT AS INFLUENCE OF THE SECOND WEATHER SYSTEM BEGINS TO
OVERSPREAD THE AREA...SCATTERED STORMS ARE LIKELY TO DEVELOP
OVERNIGHT INTO SUNDAY MORNING THAT WILL ADVANCING NORTHWARD.
THUNDER POTENTIAL WILL MAXIMIZE DURING THE LATE MORNING THROUGH
MID AFTERNOON FOR THE CHICAGO AREA TAF SITES. SOME OF THESE COULD
BE SEVERE GIVEN THE POTENT WIND FIELD AND SURPRISING INSTABILITY
WITHIN THIS SYSTEM FOR THIS TIME OF YEAR. WINDS AROUND AND UNDER
THESE STORMS WILL BE ESPECIALLY GUSTY...BUT EVEN THE PREVAILING
WINDS WILL BE VERY GUSTY BY AFTERNOON...WITH GUSTS OF 35KT+.
MTF
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM TO HIGH CONFIDENCE IN IFR CIGS THROUGH EARLY EVE.
* HIGH CONFIDENCE IN SHRA THROUGH EARLY THIS EVE.
* HIGH CONFIDENCE IN WIND DIRECTION...SPEEDS...AND GUSTS THROUGH
18Z SUNDAY...MEDIUM CONFIDENCE AFTER.
* HIGH CONFIDENCE IN 50-60KT SW WINDS IN THE 1500-3000FT LAYER
THIS EVE.
* MEDIUM CONFIDENCE IN TSRA TIMING THROUGHOUT THE TAF. HIGH
CONFIDENCE THAT IF STRONG TO SEVERE STORMS OCCUR AT THE AIRPORTS
THEY WOULD BE BE AFTER 10Z...AND MOST PROBABLE 17Z-21Z.
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...BREEZY WEST WINDS DIMINISHING LATE.
MONDAY THROUGH WEDNESDAY...VFR.
THURSDAY AND FRIDAY...SLIGHT CHANCE SHRA DURING THE DAY AND RASN
AT NIGHT. MAINLY VFR.
MDB
&&
.MARINE...
215 PM CST
A STRONG STORM SYSTEM WILL IMPACT THE GREAT LAKES REGION OVER THE
WEEKEND BRINGING PERIODS OF GALES WITH STORM FORCE WINDS A
POSSIBILITY ON THE BACK END OF THE SYSTEM. BROAD AREA OF LOW
PRESSURE IS BEGINNING TO CONSOLIDATE OVER THE NORTHERN PLAINS
TODAY...BUT WILL SIGNIFICANTLY DEEPEN OVER WISCONSIN EARLY SUNDAY
AFTERNOON...THEN CONTINUE TO DEEPEN AS IT MOVES ACROSS NORTHERN LAKE
MICHIGAN SUNDAY EVENING. SOUTHERLY GALES WILL CONTINUE THROUGH THE
OVERNIGHT HOURS INTO EARLY SUNDAY. THESE WINDS WILL TRANSPORT MOIST
AIR NORTH OVER THE WATERS WHICH IS EXPECTED TO LEAD TO AREAS OF FOG
DEVELOPMENT. IT IS UNCERTAIN HOW WIDESPREAD OR DENSE THE FOG WILL
BE...BUT A FOG ADVISORY IS NOT OUT OF THE REALM OF POSSIBILITY.
WINDS ARE EXPECTED TO EASE SLIGHTLY BELOW GALES DURING PORTIONS OF
THE DAY SUNDAY...ESPECIALLY THE NORTHERN HALF OF THE LAKE WHERE THE
GRADIENT WILL WEAKEN NEAR THE LOW CENTER. AFTER THE LOW AND
ATTENDANT COLD FRONT PUSH EAST OF THE LAKE SUNDAY EVENING...WINDS
WILL TURN WESTERLY AND QUICKLY RAMP BACK UP TO STRONG GALES OF 40 TO
45 KT...WITH OCCASIONAL STORM FORCE GUSTS STILL A POSSIBILITY. WINDS
WILL SLOWLY TAPER MONDAY AS A RIDGE OF HIGH PRESSURE BUILDS ACROSS
THE MISSISSIPPI VALLEY...AND SHOULD DROP BELOW GALES BY MID
AFTERNOON. WINDS BACK TO THE SOUTHWEST ON TUESDAY AS LOW PRESSURE
MOVES EAST ACROSS THE CANADIAN PRAIRIES. SOUTHERLY GALES MAY BE
POSSIBLE AGAIN ON WEDNESDAY AHEAD OF AN APPROACHING COLD FRONT.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WIND ADVISORY...ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-
ILZ021-ILZ022-ILZ023-ILZ032-ILZ033-ILZ039...10 AM SUNDAY TO
8 PM SUNDAY.
IN...WIND ADVISORY...INZ001-INZ002-INZ010-INZ011-INZ019...10 AM
SUNDAY TO 8 PM SUNDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY.
GALE WARNING...NEARSHORE WATERS UNTIL 4
AM MONDAY.
&&
$$
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...UPDATED
NWS CHICAGO/ROMEOVILLE IL
1233 PM CST SAT NOV 16 2013
.DISCUSSION...
1230 PM CST
ONLY SMALL CHANGES MADE TO THIS AFTERNOON FORECAST. SHOWER
COVERAGE WILL FURTHER INCREASE AHEAD OF THE WELL-DEFINED SHORT
WAVE TROUGH LIFTING NORTHEAST FROM THE NE/IA BORDER. THE MOISTURE
TRANSPORT NOSE ALONG WITH ELEVATED STEEP LAPSE RATES SEEN ON 12Z
REGIONAL SOUNDINGS WILL CONTINUE TO ADVECT OVER THE AREA
SUPPORTING AND REPLENISHING THIS ACTIVITY INTO EARLY EVE. SEVERE
POTENTIAL REMAINS VERY LOW WITH THIS. TEMPERATURES SHOULD CONTINUE
TO WARM ESPECIALLY OUTSIDE OF THE SHOWERS...JUST SIMPLY BY PURE
ADVECTION.
PRONOUNCED REGIONAL SEVERE THREAT CONTINUES FOR LATE TONIGHT INTO
SUNDAY AFTERNOON. NEW SPC MODERATE RISK DOES INCLUDE A LARGER
PORTION OF THE FORECAST AREA...INCLUDING ALL OF CHICAGOLAND.
UPDATED DISCUSSION ON THIS WILL BE POSTED BY 300 PM.
MTF
&&
.PREV DISCUSSION...
815 AM CST
FORECAST UPDATED TO ADD DRIZZLE IN THROUGH THIS MORNING.
THE LOW-LEVEL MOISTURE SURGE CONTINUES TO RETURN OVER THE AREA.
ISENTROPIC ASCENT ON THE RAP ANALYSIS OF 285K AND 290K SURFACES
HAS RAPIDLY SATURATED AND LOOKS TO BE THE ROOT OF THIS. EVEN ON
THE 12Z ILX RAOB...THE PROFILE WAS VERY SUGGESTIVE OF DRIZZLE.
THIS COULD CONTINUE INTO THIS AFTERNOON BASED ON THE EXTENT OF
UPSTREAM OBS ACROSS CENTRAL AND SOUTHERN IL. SOUTH WINDS CONTINUE
TO BRING WARM AIR ADVECTION SO TEMPERATURES WILL INCH UPWARD. THE
CHANCE FOR TRUE SHOWERS AND POSSIBLY SOME STORMS TODAY STILL LOOKS
TO ARRIVE WITH A SHORT WAVE ACROSS THE WESTERN FORECAST AREA BY
EARLY AFTERNOON AND SPREADING EAST FROM THERE.
MTF
//PREV DISCUSSION...
333 AM...FORECAST FOCUS REMAINS POTENTIAL SEVERE WEATHER OUTBREAK
ACROSS THE SOUTHERN LAKES AND OHIO VALLEY ON SUNDAY.
IN THE SHORT TERM...LOW CLOUDS HAVE STREAMED NORTH ACROSS THE AREA
SIGNALING THE BEGINNING OF A SURGE OF LOW LEVEL MOISTURE.
DEWPOINTS SLOWLY CREEPING INTO THE LOWER 40S EARLY THIS MORNING
WILL CONTINUE TO RISE INTO THE LOWER/MID 50S THIS AFTERNOON...UPPER
50S TONIGHT AND LIKELY POOL IN THE LOWER TO PERHAPS MID 60S JUST
AHEAD OF THE COLD FRONT SUNDAY MORNING.
LOW PRESSURE OVER NEBRASKA WILL LIFT NORTH TO MINNESOTA BY THIS
EVENING AND AS IT DOES...AN UPPER LEVEL WAVE WILL MOVE ACROSS THE
AREA THIS AFTERNOON INTO THIS EVENING. MUCH OF THE EASTERN HALF OR
TWO THIRDS WILL LIKELY REMAIN DRY THIS MORNING WITH PRECIP
SPREADING ACROSS THE WESTERN CWA BY LATE MORNING. HAVE INCLUDED
JUST A CHANCE OF THUNDERSTORMS WITH THE STRONGER/CONVECTIVE
ELEMENTS BUT CONFIDENCE REGARDING HOW WIDESPREAD LIGHTNING/THUNDER
WILL BECOME IS SOMEWHAT LOW AND THUNDER COVERAGE MAY NEED TO BE
INCREASED BASED ON SHORT TERM TRENDS ONCE PRECIP DEVELOPS/ARRIVES.
THIS ACTIVITY SHOULD MOVE NORTHEAST OF THE AREA BY MID/LATE EVENING
WITH A POSSIBLE LULL IN ACTIVITY INTO THE EARLY MORNING HOURS. NOT
EXPECTING ANY OF THE THUNDERSTORMS DURING THIS FIRST WAVE TO BE
SEVERE. SOME COULD PRODUCE STRONG/GUSTY WINDS AS WELL AS HEAVY
RAIN. THOUGH STORM MOTION SHOULD BE SUFFICIENTLY FAST TO PREVENT A
LONG DURATION HEAVY RAIN IN ANY ONE LOCATION. RAINFALL AMOUNTS
WITH THIS WAVE APPEAR TO BE IN THE 0.5 TO 0.75 RANGE.
DESPITE MAINLY CLOUDY SKIES TODAY AND THEN PRECIP THIS
AFTERNOON...WITH THE NOTED SURGE IN LOW LEVEL MOISTURE...TEMPS
WILL CONTINUE TO CLIMB THROUGH THE DAY WITH CURRENT TEMPS ALREADY
IN THE LOWER 50S ACROSS SOUTHERN IL. THUS...HIGHS IN THE UPPER 50S
TO LOWER 60S LOOK ON TRACK AND MUCH OF THE SOUTHERN THIRD/HALF OF
THE CWA MAY NOT SEE PRECIP UNTIL LATE THIS AFTERNOON AND IF ANY
BREAKS DEVELOP...THIS WILL AID TEMPS FURTHER. AS PRECIP ENDS THIS
EVENING...POSSIBLE FOR SOME LOCATIONS...ESPECIALLY NORTHERN
CWA...TO CONTINUE TO WARM WITH HIGHS BEING REACHED IN THE EVENING.
A SECOND LOW THEN DEVELOPS OVER EASTERN COLORADO TONIGHT AND
QUICKLY SHIFTS EAST TO IOWA BY SUNDAY MORNING...THEN RAPIDLY
DEEPENS AS IT ABSORBS THE FIRST LOW OVER MINNESOTA...AND REACHES
LAKE SUPERIOR BY SUNDAY EVENING. A STRONG COLD FRONT WILL RACE
ACROSS THE CWA FROM MID/LATE SUNDAY MORNING THROUGH EARLY/MID
SUNDAY AFTERNOON. ANOTHER WAVE OF THUNDERSTORMS IS POSSIBLE IN THE
EARLY MORNING HOURS OF SUNDAY AHEAD OF THIS SECOND LOW...
DEVELOPING OVER EASTERN IOWA AND NORTHWEST IL THEN MOVING INTO
SOUTHERN WI...MOSTLY LIKELY BY SUNRISE. AT THE SAME TIME...
ADDITIONAL THUNDERSTORMS COULD BE DEVELOPING AHEAD OF THE COLD
FRONT ACROSS PARTS OF IOWA/MISSOURI. ANY OF THESE THUNDERSTORMS
OVERNIGHT INTO EARLY SUNDAY MORNING COULD BECOME SEVERE. BUT TO
WHAT EXTENT AND HOW WIDESPREAD ANY SEVERE WEATHER WOULD BECOME IS
UNCERTAIN. HOWEVER...WITH SUCH WARM/MOIST LOW LEVELS...A DEEPENING
SURFACE LOW AND WHAT COULD END UP BEING A WARM FRONTAL BOUNDARY
ACROSS THE NORTHERN CWA...THE THREAT OF A TORNADO WITH ANY STRONG
STORMS CAN/T BE RULED OUT.
ANOTHER BRIEF LULL IS EXPECTED SUNDAY MORNING BEFORE WHAT APPEARS
LIKE IT COULD BE THE BEGINNING OF A WIDESPREAD SEVERE WEATHER
OUTBREAK DEVELOPS. WINDS THROUGH THE ENTIRE COLUMN REMAIN VERY
IMPRESSIVE WITH 50 KNOTS AS LOW AS 900MB SUNDAY MORNING. AS
NOTED...WHILE THE WARM/MOIST CONDITIONS WILL HELP/AID STORMS
STAYING SURFACE BASED...EXPECT QUITE A BIT OF CLOUD COVER...AND
WHILE HAVE TRIED TO SHOW SOME PARTLY/MOSTLY CLOUDY CONDITIONS AT
LEAST ACROSS THE SOUTHEAST CWA SUNDAY MORNING...ITS POSSIBLE
OVERCAST CONDITIONS WILL PERSIST UNTIL FROPA. ADDITIONAL
UNCERTAINTY REMAINS WITH WHERE/WHEN THUNDERSTORMS WILL DEVELOP...
JUST WEST OF THE CWA...OVER THE CWA...EASTERN CWA/NORTHWEST
INDIANA. ENTIRE CWA IS NOW INCLUDED IN SLIGHT RISK PER THIS
MORNING/S SPC DAY2 OUTLOOK WITH MODERATE RISK EAST OF THE
I-55/I-57 CORRIDOR. POTENTIAL IS CERTAINLY HIGHER OVER THE EASTERN
CWA BUT EVEN FROM THIS DISTANCE WILL BE INCLUDING SEVERE
MENTION/DAMAGING WINDS IN THE ZONES/GRIDS. THUNDERSTORMS WILL BE
ENDING FROM WEST TO EAST DURING THE MID/LATE AFTERNOON AND ALSO
ATTEMPTED TO INCLUDE THIS TIMING IN THE GRIDS. THE THREAT OF A
TORNADO OR TWO WILL REMAIN SUNDAY BUT DAMAGING WINDS APPEAR TO BE
THE PRIMARY SEVERE WEATHER THREAT. DESPITE PRECIPITABLE WATER
VALUES ONLY AROUND AN INCH...EXPECT VERY EFFICIENT RAIN PRODUCTION
WITH ANOTHER 0.5-0.75 INCHES POSSIBLE...ALTHOUGH PERHAPS MORE
LOCALIZED DEPENDING ON CONVECTIVE COVERAGE.
STRONG WINDS FROM THE SOUTH WILL DEVELOP TODAY WITH GUSTS INTO THE
30-35 MPH RANGE POSSIBLE. STILL APPEARS THERE COULD BE A 3-6 HOUR
WINDOW THIS EVENING OF GUSTS 40+ MPH BEFORE WINDS DIMINISH SOME
OVERNIGHT...WHILE CLOSE TO WIND ADVISORY CRITERIA...NOT SURE IT
WILL BE REACHED AND NO HEADLINES THROUGH TONIGHT. BY SUNDAY...
LOW LEVEL WINDS ARE WELL INTO ADVISORY CRITERIA AND SOME OF THIS
WILL LIKELY MIX TO THE SURFACE ESPECIALLY JUST BEHIND THE STORMS/
COLD FRONT AS COLD ADVECTION IS AIDED BY LARGE PRESSURE RISES.
THIS IS THIRD PERIOD AND A BIT EARLY FOR AN ADVISORY AND LATER
SHIFTS WILL NEED TO ASSESS WIND POTENTIAL/HEADLINES FOR SUNDAY.
HAVE CONTINUED INCREASING HIGH TEMPS FOR SUNDAY WITH MID 60S NORTH
TO UPPER 60S FROM I-55 SOUTH AND ITS QUITE POSSIBLE SOME AREAS MAY
SEE TEMPS TAG 70 AHEAD OF THE FRONT...ESPECIALLY WITH ANY BREAKS
IN THE OVERCAST AS 850MB TEMPS ARE NOW EXPECTED TO BE IN THE +12C
TO +15C RANGE.
WRAP AROUND SHOWERS WILL BE POSSIBLE SUNDAY EVENING BUT SHOULD BE
ENDING FAIRLY QUICKLY WITH CLEARING SKIES OVERNIGHT AS HIGH
PRESSURE BUILDS INTO THE REGION MONDAY AFTERNOON/MONDAY NIGHT AND
THIS HIGH IS MOVING FASTER THAN PREVIOUS MODELS HAD SUGGESTED.
WHILE IT WILL TURN MUCH COLDER MONDAY NIGHT WITH LOWS IN THE 30S...
MONDAY MAY END UP BEING MAINLY SUNNY WITH DIMINISHING WINDS IN THE
AFTERNOON AND TEMPS REBOUNDING BACK INTO THE MID 40S. STILL WILL
FEEL MUCH COLDER COMPARED TO SUNDAY...BUT THE TREND IS SLIGHTLY
WARMER.
HAVE CONTINUED THE WARMING TREND TUESDAY THROUGH THURSDAY AS WINDS
TURN SOUTHERLY SOONER ON THE BACK SIDE OF THE DEPARTING HIGH. ALSO
NOW APPEARS THE CHANCE OF SHOWERS WILL ARRIVE SOONER...PERHAPS AS
EARLY AS LATE WEDNESDAY BUT CERTAINLY WEDNESDAY NIGHT INTO
THURSDAY. WARMING TEMPS DURING THIS PERIOD WITH SOUTHERLY FLOW
SHOULD KEEP PRECIP MAINLY LIQUID. A COLD FRONT THEN MOVES SOUTH
THURSDAY NIGHT AND FRIDAY WITH THE ECMWF MUCH COLDER THAN THE GFS
AND HAVE LOWERED TEMPS A FEW DEGREES DURING THIS TIME PERIOD AND
WHILE ITS STILL SEVERAL DAYS AWAY...POTENTIAL FOR SOME FROZEN
PRECIP EXISTS LATER FRIDAY/FRIDAY NIGHT...DEPENDING ON SPEED OF
FRONT AND END TIME OF PRECIP. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* IFR CIGS THIS AFTERNOON AND POTENTIALLY THROUGH TONIGHT.
* SHRA WITH GRADUALLY INCREASING CHANCES FOR THUNDER THROUGH
EARLY EVE.
* SOUTH WINDS GUSTING TO AROUND 30 KT AT TIMES THROUGH THIS
EVE...THEN TURNING SOUTHWEST AND BECOMING EVEN MORE GUSTY ON
SUNDAY AFTERNOON.
* LOW LEVEL WIND SHEAR POSSIBLE AS WINDS NEAR 1500 FT INCREASE TO
50 KT OR STRONGER.
* TSRA CHANCES INCREASING AROUND DAYBREAK WITH GUSTY SEVERE STORM
POTENTIAL THIS MORNING AND EARLY AFTERNOON.
//DISCUSSION...UPDATED 18Z...
INITIAL LOW PRESSURE MOVING NORTHWARD INTO MN CONTINUES TO
INCREASE SOUTHERLY WINDS ACROSS THE AREA...AND AS AN EVEN MORE
POTENT LOW PRESSURE DEVELOPS ON SUNDAY THE SOUTH WINDS WILL REALLY
RAMP UP. SOUTHERLY GUSTS TO 30 KT OR EVEN SLIGHTLY HIGHER MAY BE
SEEN THIS AFTERNOON. SHOWERS WITH EMBEDDED SCATTERED THUNDER WILL
INCREASE IN COVERAGE THROUGH LATE AFTERNOON WITH THIS INITIAL LOW
PRESSURE. THERE PROBABLY WILL BE A SLIGHT DIMINISHING IN COVERAGE
THEN THROUGH THE MID TO LATE EVE AS THIS INITIAL MOISTURE SURGE
PASSES. BUT AS INFLUENCE OF THE SECOND WEATHER SYSTEM BEGINS TO
OVERSPREAD THE AREA...SCATTERED STORMS ARE LIKELY TO DEVELOP
OVERNIGHT INTO SUNDAY MORNING THAT WILL ADVANCING NORTHWARD.
THUNDER POTENTIAL WILL MAXIMIZE DURING THE LATE MORNING THROUGH
MID AFTERNOON FOR THE CHICAGO AREA TAF SITES. SOME OF THESE COULD
BE SEVERE GIVEN THE POTENT WIND FIELD AND SURPRISING INSTABILITY
WITHIN THIS SYSTEM FOR THIS TIME OF YEAR. WINDS AROUND AND UNDER
THESE STORMS WILL BE ESPECIALLY GUSTY...BUT EVEN THE PREVAILING
WINDS WILL BE VERY GUSTY BY AFTERNOON...WITH GUSTS OF 35KT+.
MTF
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM TO HIGH CONFIDENCE IN IFR CIGS THROUGH EARLY EVE.
* HIGH CONFIDENCE IN SHRA THROUGH EARLY THIS EVE.
* HIGH CONFIDENCE IN WIND DIRECTION...SPEEDS...AND GUSTS THROUGH
18Z SUNDAY...MEDIUM CONFIDENCE AFTER.
* HIGH CONFIDENCE IN 50-60KT SW WINDS IN THE 1500-3000FT LAYER
THIS EVE.
* MEDIUM CONFIDENCE IN TSRA TIMING THROUGHOUT THE TAF. HIGH
CONFIDENCE THAT IF STRONG TO SEVERE STORMS OCCUR AT THE AIRPORTS
THEY WOULD BE BE AFTER 10Z...AND MOST PROBABLE 17Z-21Z.
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...BREEZY WEST WINDS DIMINISHING LATE.
MONDAY THROUGH WEDNESDAY...VFR.
THURSDAY AND FRIDAY...SLIGHT CHANCE SHRA DURING THE DAY AND RASN
AT NIGHT. MAINLY VFR.
MDB
&&
.MARINE...
354 AM CST
GALES THROUGH MONDAY AND A POTENTIAL PERIOD OF STORM FORCE WINDS
SUNDAY EVENING ARE THE FOCUS OF THIS FORECAST PERIOD. HIGH
PRESSURE REMAINS CENTERED OFF THE EAST COAST WITH EFFECTS OF THE
HIGH SPREAD BACK INTO THE EASTERN LAKES. LOW PRESSURE IS SPREAD
ACROSS THE PLAINS AND UPPER MIDWEST WITH CONSOLIDATION EXPECTED TO
OCCUR RESULTING IN A LOW TRACKING NORTHEAST TO WESTERN LAKE
SUPERIOR SUNDAY MORNING. THE PRESSURE GRADIENT WILL TIGHTEN AS
THIS LOW ORGANIZES ALLOWING SOUTH WINDS TO STEADILY INCREASE
ACROSS THE LAKE TODAY. WARMER AIR WILL BE MOVING INTO THE REGION
WHICH WILL CREATE SOME DEGREE OF A STABLE LAYER OVER THE LAKE
TODAY BUT GALES ARE STILL LIKELY TO DEVELOP THIS AFTERNOON AND
CONTINUE THIS EVENING. GALES WILL BE A BIT MORE MARGINAL IN THE
IL/IN NEARSHORE WATERS BUT OPTED TO HOIST A GALE WARNING FOR THESE
AREAS WITH 30 KT LIKELY AND DECENT POTENTIAL FOR GALE FORCE GUSTS
WITH QUITE A BIT OF WIND JUST ABOVE THE SURFACE...WITH BETTER
MIXING POSSIBLE THANKS TO AN OFFSHORE COMPONENT AT TIMES.
WINDS WILL EASE UP FOR A BRIEF PERIOD LATE TONIGHT AND EARLY
SUNDAY MORNING SO SPEEDS MAY FALL BELOW GALE FOR SEVERAL
HOURS...BUT WINDS WILL INCREASE AGAIN BY SUNDAY AFTERNOON AS A
STRONGER LOW EJECTS NORTHEAST FROM EASTERN COLORADO. THIS LOW WILL
RAPIDLY DEEPEN AS IT REACHES WISCONSIN AND THE EASTERN U.P. OF
MICHIGAN BY SUNDAY EVENING. MUCH WARMER AIR WILL BE DRAWN
NORTHWARD ACROSS THE LAKE BUT THE GRADIENT WILL BE TIGHT ENOUGH TO
SUPPORT GALES...EVEN IF MIXING IS VERY SHALLOW OVER THE COLDER
LAKE WATER. NEARSHORE AREAS MAY SEE THE STRONGEST WINDS DURING THE
DAY SUNDAY AS THE FLOW TURNS SOUTHWESTERLY AND WELL MIXED AIR
MOVES OFFSHORE. A FURTHER SHIFT TO WESTERLY WINDS WILL OCCUR AS
THE LOW FURTHER DEEPENS AND CONTINUES NORTHEAST DRAGGING A SHARP
COLD FRONT ACROSS THE LAKE BY SUNDAY EVENING. WITH THE DEEPENING
LOW AND UNSTABLE CONDITIONS DEVELOPING WINDS SHOULD INCREASE TO 45
KT WITH A DECENT POTENTIAL FOR 50 KT STORM FORCE WINDS SUNDAY
EVENING AND EARLY SUNDAY NIGHT. HAVE DECIDED TO EXTEND THE GALE
WARNING FROM LATE TONIGHT THROUGH MONDAY AFTERNOON AND EXPAND INTO
THE NEARSHORE WATERS...WITH AN EARLIER END TIME. WILL NEED TO KEEP
AN EYE ON THE DURATION OF ANY LULL PERIOD EARLY SUNDAY WHICH MAY
ALLOW FOR A SHORT WINDOW WITHOUT A GALE BUT AT THIS POINT THE
WINDOW LOOKS RATHER SHORT...ON THE ORDER OF 6-9 HOURS. STILL DO
HAVE SOME UNCERTAINTY ON THE TRACK OF THE LOW...WHETHER IT CROSSES
THE NORTHERN PART OF THE LAKE OR REMAINS JUST TO THE WEST AND
NORTH. RIGHT NOW PREFER THE WESTERN TRACK WHICH WOULD PROVIDE A
CLEANER SOUTHWEST TO WEST SHIFT OF THE WINDS AS OPPOSED THE
EASTERLY TRACK WHICH WOULD RESULT IN A BRIEF PERIOD OF NORTHERLY
WINDS OVER THE NORTHERN SECTIONS OF THE LAKE. WILL NEED TO KEEP AN
EYE ON THIS.
OTHERWISE WINDS WILL SLOWLY DIMINISH MONDAY AS HIGH PRESSURE
PASSES TO THE SOUTH AND EAST OF THE LAKE. LOW PRESSURE IS THEN
EXPECTED TO CROSS THE CANADIAN PRAIRIES TO JAMES BAY DURING THE
MIDDLE OF NEXT WEEK BRINGING ANOTHER INCREASE IN SOUTH WINDS WHICH
WILL FLIP NORTHWEST WITH A COLD FRONTAL PASSAGE LATER THURSDAY.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL NOON SATURDAY.
GALE WARNING...NEARSHORE WATERS UNTIL 4
AM MONDAY.
GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY.
&&
$$
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 CHICAGO/ROMEOVILLE IL
957 AM CST SAT NOV 16 2013
.DISCUSSION...
815 AM CST
FORECAST UPDATED TO ADD DRIZZLE IN THROUGH THIS MORNING.
THE LOW-LEVEL MOISTURE SURGE CONTINUES TO RETURN OVER THE AREA.
ISENTROPIC ASCENT ON THE RAP ANALYSIS OF 285K AND 290K SURFACES
HAS RAPIDLY SATURATED AND LOOKS TO BE THE ROOT OF THIS. EVEN ON
THE 12Z ILX RAOB...THE PROFILE WAS VERY SUGGESTIVE OF DRIZZLE.
THIS COULD CONTINUE INTO THIS AFTERNOON BASED ON THE EXTENT OF
UPSTREAM OBS ACROSS CENTRAL AND SOUTHERN IL. SOUTH WINDS CONTINUE
TO BRING WARM AIR ADVECTION SO TEMPERATURES WILL INCH UPWARD. THE
CHANCE FOR TRUE SHOWERS AND POSSIBLY SOME STORMS TODAY STILL LOOKS
TO ARRIVE WITH A SHORT WAVE ACROSS THE WESTERN FORECAST AREA BY
EARLY AFTERNOON AND SPREADING EAST FROM THERE.
MTF
//PREV DISCUSSION...
333 AM...FORECAST FOCUS REMAINS POTENTIAL SEVERE WEATHER OUTBREAK
ACROSS THE SOUTHERN LAKES AND OHIO VALLEY ON SUNDAY.
IN THE SHORT TERM...LOW CLOUDS HAVE STREAMED NORTH ACROSS THE AREA
SIGNALING THE BEGINNING OF A SURGE OF LOW LEVEL MOISTURE.
DEWPOINTS SLOWLY CREEPING INTO THE LOWER 40S EARLY THIS MORNING
WILL CONTINUE TO RISE INTO THE LOWER/MID 50S THIS AFTERNOON...UPPER
50S TONIGHT AND LIKELY POOL IN THE LOWER TO PERHAPS MID 60S JUST
AHEAD OF THE COLD FRONT SUNDAY MORNING.
LOW PRESSURE OVER NEBRASKA WILL LIFT NORTH TO MINNESOTA BY THIS
EVENING AND AS IT DOES...AN UPPER LEVEL WAVE WILL MOVE ACROSS THE
AREA THIS AFTERNOON INTO THIS EVENING. MUCH OF THE EASTERN HALF OR
TWO THIRDS WILL LIKELY REMAIN DRY THIS MORNING WITH PRECIP
SPREADING ACROSS THE WESTERN CWA BY LATE MORNING. HAVE INCLUDED
JUST A CHANCE OF THUNDERSTORMS WITH THE STRONGER/CONVECTIVE
ELEMENTS BUT CONFIDENCE REGARDING HOW WIDESPREAD LIGHTNING/THUNDER
WILL BECOME IS SOMEWHAT LOW AND THUNDER COVERAGE MAY NEED TO BE
INCREASED BASED ON SHORT TERM TRENDS ONCE PRECIP DEVELOPS/ARRIVES.
THIS ACTIVITY SHOULD MOVE NORTHEAST OF THE AREA BY MID/LATE EVENING
WITH A POSSIBLE LULL IN ACTIVITY INTO THE EARLY MORNING HOURS. NOT
EXPECTING ANY OF THE THUNDERSTORMS DURING THIS FIRST WAVE TO BE
SEVERE. SOME COULD PRODUCE STRONG/GUSTY WINDS AS WELL AS HEAVY
RAIN. THOUGH STORM MOTION SHOULD BE SUFFICIENTLY FAST TO PREVENT A
LONG DURATION HEAVY RAIN IN ANY ONE LOCATION. RAINFALL AMOUNTS
WITH THIS WAVE APPEAR TO BE IN THE 0.5 TO 0.75 RANGE.
DESPITE MAINLY CLOUDY SKIES TODAY AND THEN PRECIP THIS
AFTERNOON...WITH THE NOTED SURGE IN LOW LEVEL MOISTURE...TEMPS
WILL CONTINUE TO CLIMB THROUGH THE DAY WITH CURRENT TEMPS ALREADY
IN THE LOWER 50S ACROSS SOUTHERN IL. THUS...HIGHS IN THE UPPER 50S
TO LOWER 60S LOOK ON TRACK AND MUCH OF THE SOUTHERN THIRD/HALF OF
THE CWA MAY NOT SEE PRECIP UNTIL LATE THIS AFTERNOON AND IF ANY
BREAKS DEVELOP...THIS WILL AID TEMPS FURTHER. AS PRECIP ENDS THIS
EVENING...POSSIBLE FOR SOME LOCATIONS...ESPECIALLY NORTHERN
CWA...TO CONTINUE TO WARM WITH HIGHS BEING REACHED IN THE EVENING.
A SECOND LOW THEN DEVELOPS OVER EASTERN COLORADO TONIGHT AND
QUICKLY SHIFTS EAST TO IOWA BY SUNDAY MORNING...THEN RAPIDLY
DEEPENS AS IT ABSORBS THE FIRST LOW OVER MINNESOTA...AND REACHES
LAKE SUPERIOR BY SUNDAY EVENING. A STRONG COLD FRONT WILL RACE
ACROSS THE CWA FROM MID/LATE SUNDAY MORNING THROUGH EARLY/MID
SUNDAY AFTERNOON. ANOTHER WAVE OF THUNDERSTORMS IS POSSIBLE IN THE
EARLY MORNING HOURS OF SUNDAY AHEAD OF THIS SECOND LOW...
DEVELOPING OVER EASTERN IOWA AND NORTHWEST IL THEN MOVING INTO
SOUTHERN WI...MOSTLY LIKELY BY SUNRISE. AT THE SAME TIME...
ADDITIONAL THUNDERSTORMS COULD BE DEVELOPING AHEAD OF THE COLD
FRONT ACROSS PARTS OF IOWA/MISSOURI. ANY OF THESE THUNDERSTORMS
OVERNIGHT INTO EARLY SUNDAY MORNING COULD BECOME SEVERE. BUT TO
WHAT EXTENT AND HOW WIDESPREAD ANY SEVERE WEATHER WOULD BECOME IS
UNCERTAIN. HOWEVER...WITH SUCH WARM/MOIST LOW LEVELS...A DEEPENING
SURFACE LOW AND WHAT COULD END UP BEING A WARM FRONTAL BOUNDARY
ACROSS THE NORTHERN CWA...THE THREAT OF A TORNADO WITH ANY STRONG
STORMS CAN/T BE RULED OUT.
ANOTHER BRIEF LULL IS EXPECTED SUNDAY MORNING BEFORE WHAT APPEARS
LIKE IT COULD BE THE BEGINNING OF A WIDESPREAD SEVERE WEATHER
OUTBREAK DEVELOPS. WINDS THROUGH THE ENTIRE COLUMN REMAIN VERY
IMPRESSIVE WITH 50 KNOTS AS LOW AS 900MB SUNDAY MORNING. AS
NOTED...WHILE THE WARM/MOIST CONDITIONS WILL HELP/AID STORMS
STAYING SURFACE BASED...EXPECT QUITE A BIT OF CLOUD COVER...AND
WHILE HAVE TRIED TO SHOW SOME PARTLY/MOSTLY CLOUDY CONDITIONS AT
LEAST ACROSS THE SOUTHEAST CWA SUNDAY MORNING...ITS POSSIBLE
OVERCAST CONDITIONS WILL PERSIST UNTIL FROPA. ADDITIONAL
UNCERTAINTY REMAINS WITH WHERE/WHEN THUNDERSTORMS WILL DEVELOP...
JUST WEST OF THE CWA...OVER THE CWA...EASTERN CWA/NORTHWEST
INDIANA. ENTIRE CWA IS NOW INCLUDED IN SLIGHT RISK PER THIS
MORNING/S SPC DAY2 OUTLOOK WITH MODERATE RISK EAST OF THE
I-55/I-57 CORRIDOR. POTENTIAL IS CERTAINLY HIGHER OVER THE EASTERN
CWA BUT EVEN FROM THIS DISTANCE WILL BE INCLUDING SEVERE
MENTION/DAMAGING WINDS IN THE ZONES/GRIDS. THUNDERSTORMS WILL BE
ENDING FROM WEST TO EAST DURING THE MID/LATE AFTERNOON AND ALSO
ATTEMPTED TO INCLUDE THIS TIMING IN THE GRIDS. THE THREAT OF A
TORNADO OR TWO WILL REMAIN SUNDAY BUT DAMAGING WINDS APPEAR TO BE
THE PRIMARY SEVERE WEATHER THREAT. DESPITE PRECIPITABLE WATER
VALUES ONLY AROUND AN INCH...EXPECT VERY EFFICIENT RAIN PRODUCTION
WITH ANOTHER 0.5-0.75 INCHES POSSIBLE...ALTHOUGH PERHAPS MORE
LOCALIZED DEPENDING ON CONVECTIVE COVERAGE.
STRONG WINDS FROM THE SOUTH WILL DEVELOP TODAY WITH GUSTS INTO THE
30-35 MPH RANGE POSSIBLE. STILL APPEARS THERE COULD BE A 3-6 HOUR
WINDOW THIS EVENING OF GUSTS 40+ MPH BEFORE WINDS DIMINISH SOME
OVERNIGHT...WHILE CLOSE TO WIND ADVISORY CRITERIA...NOT SURE IT
WILL BE REACHED AND NO HEADLINES THROUGH TONIGHT. BY SUNDAY...
LOW LEVEL WINDS ARE WELL INTO ADVISORY CRITERIA AND SOME OF THIS
WILL LIKELY MIX TO THE SURFACE ESPECIALLY JUST BEHIND THE STORMS/
COLD FRONT AS COLD ADVECTION IS AIDED BY LARGE PRESSURE RISES.
THIS IS THIRD PERIOD AND A BIT EARLY FOR AN ADVISORY AND LATER
SHIFTS WILL NEED TO ASSESS WIND POTENTIAL/HEADLINES FOR SUNDAY.
HAVE CONTINUED INCREASING HIGH TEMPS FOR SUNDAY WITH MID 60S NORTH
TO UPPER 60S FROM I-55 SOUTH AND ITS QUITE POSSIBLE SOME AREAS MAY
SEE TEMPS TAG 70 AHEAD OF THE FRONT...ESPECIALLY WITH ANY BREAKS
IN THE OVERCAST AS 850MB TEMPS ARE NOW EXPECTED TO BE IN THE +12C
TO +15C RANGE.
WRAP AROUND SHOWERS WILL BE POSSIBLE SUNDAY EVENING BUT SHOULD BE
ENDING FAIRLY QUICKLY WITH CLEARING SKIES OVERNIGHT AS HIGH
PRESSURE BUILDS INTO THE REGION MONDAY AFTERNOON/MONDAY NIGHT AND
THIS HIGH IS MOVING FASTER THAN PREVIOUS MODELS HAD SUGGESTED.
WHILE IT WILL TURN MUCH COLDER MONDAY NIGHT WITH LOWS IN THE 30S...
MONDAY MAY END UP BEING MAINLY SUNNY WITH DIMINISHING WINDS IN THE
AFTERNOON AND TEMPS REBOUNDING BACK INTO THE MID 40S. STILL WILL
FEEL MUCH COLDER COMPARED TO SUNDAY...BUT THE TREND IS SLIGHTLY
WARMER.
HAVE CONTINUED THE WARMING TREND TUESDAY THROUGH THURSDAY AS WINDS
TURN SOUTHERLY SOONER ON THE BACK SIDE OF THE DEPARTING HIGH. ALSO
NOW APPEARS THE CHANCE OF SHOWERS WILL ARRIVE SOONER...PERHAPS AS
EARLY AS LATE WEDNESDAY BUT CERTAINLY WEDNESDAY NIGHT INTO
THURSDAY. WARMING TEMPS DURING THIS PERIOD WITH SOUTHERLY FLOW
SHOULD KEEP PRECIP MAINLY LIQUID. A COLD FRONT THEN MOVES SOUTH
THURSDAY NIGHT AND FRIDAY WITH THE ECMWF MUCH COLDER THAN THE GFS
AND HAVE LOWERED TEMPS A FEW DEGREES DURING THIS TIME PERIOD AND
WHILE ITS STILL SEVERAL DAYS AWAY...POTENTIAL FOR SOME FROZEN
PRECIP EXISTS LATER FRIDAY/FRIDAY NIGHT...DEPENDING ON SPEED OF
FRONT AND END TIME OF PRECIP. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* DRIZZLE AND IFR CONDITIONS THROUGH EARLY AFTERNOON...WITH EVEN
A CHANCE OF TEMPORARY LIFR.
* MVFR CIGS LIKELY WITH A CHANCE OF IFR CIGS TONIGHT.
* SOUTH WINDS INCREASING THROUGH THE MORNING WITH GUSTS 25-30 KT
THIS AFTERNOON. SOUTH TO SOUTHWEST WIND GUSTS IN EXCESS OF 30 KT
EXPECTED SUNDAY.
* SHRA EXPECTED LATE THIS AFTERNOON THROUGH THE EVENING WITH
THUNDER POSSIBLE. ADDITIONAL LOWER SHRA/TSRA CHANCES OVERNIGHT
WITH AN INCREASING CHANCE AFTER DAYBREAK SUNDAY.
* LOW LEVEL WIND SHEAR POSSIBLE AS WINDS NEAR 1500 FT INCREASE TO
50 KT.
MTF/MDB
//DISCUSSION...UPDATED 14Z...
TAFS HAVE BEEN UPDATED TO INCLUDE MORE PESSIMISTIC CONDITIONS THIS
MORNING DUE TO DRIZZLE AND IFR VISIBLITIES. IFR CONDITIONS EXIST
WELL UPSTREAM ACROSS CENTRAL IL SO MAY NEED TO EXTEND DURATION
INTO THE AFTERNOON. THERE HAVE BEEN TEMPORARY LIFR CONDITIONS
OBSERVED AT SOME AIRPORTS AND POSSIBLE THIS IS SEEN AT SOME OF THE
TAF SITES THROUGH EARLY AFTERNOON.
PREV DISCUSSION...UPDATED 12Z...
LOW PRESSURE IS ORGANIZING ACROSS THE CENTRAL AND NORTHERN PLAINS
AND WILL MOVE NORTHEAST TO LAKE SUPERIOR TONIGHT. INCREASING
SOUTHERLY FLOW HAS BROUGHT AN INFLUX OF STRATUS AND SOME MIST TO
THE TERMINALS OVERNIGHT. SEVERAL SITES HAD DIPPED TO IFR BUT HAVE
BEEN SEEING IMPROVEMENT UPSTREAM OVER THE LAST HOUR OR TWO. EXPECT
THE IFR CIGS/VSBY TO IMPROVE WITH A STEADIER MVFR CLOUD DECK
BECOMING ESTABLISHED THROUGH THE MORNING...LIKELY IN THE 1000-2000
FT RANGE. MVFR LOOKS TO CONTINUE THROUGH THE NIGHT...THOUGH THERE
MAY BE SOME BREAKS AT TIMES LATER TODAY AND TONIGHT BUT CONFIDENCE
IN DETAILS IS LOW. WINDS WILL BE INCREASING THROUGH THE MORNING
WITH GUSTS BECOMING MORE FREQUENT INTO THE AFTERNOON AS GUSTS
SPEEDS PUSH 25 TO 30 KT. AN UPPER LEVEL TROUGH WILL CROSS THE AREA
LATE THIS AFTERNOON AND THIS EVENING BRINGING SHOWERS WITH IT AS
WELL AS AT LEAST A CHANCE FOR THUNDER. HAVE DECENT CONFIDENCE IN
THUNDER OCCURRING THOUGH TI MAY NIT IMPACT EACH TERMINAL DIRECTLY.
THERE LOOKS TO BE A LULL IN THE PRECIP LATER THIS EVENING AND
EARLY TONIGHT BEFORE CHANCE INCREASE EARLY SUNDAY MORNING AS
ANOTHER PUSH OF WARMER AIR STREAMS OVER. CIGS MAY LOWER TO IFR
OVERNIGHT BUT WILL JUST HINT AT IT WITH SCT IFR LEVEL CLOUD
MENTION FOR NOW. WIND GUSTS SHOULD CONTINUE THROUGH THE EVENING
AND MAY EVEN INCREASE. RAIN.THUNDER COVERAGE AND TIMING IS
SOMEWHAT UNCERTAIN GOING INTO SUNDAY MORNING BUT CHANCES WILL
LIKELY INCREASE UNTIL A COLD FRONT CROSSES THE AREA IN CONJUNCTION
WITH A SECOND AND MORE INTENSE LOW PRESSURE AREA MOVING NORTH OF
THE AREA. SOUTH TO SOUTHWEST WINDS WILL INCREASE SUNDAY MORNING
AND GUSTS IN EXCESS OF 35 KT A GOOD POSSIBILITY...WITH THE
DIRECTION TURNING MORE WESTERLY THROUGH THE DAY.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH CONFIDENCE IN IFR CONDITIONS LATE THIS MORNING WITH AT
LEAST TEMPORARY SUB 700 FT CIGS AND <3SM VISIBILITY. LOW
CONFIDENCE IN DURATION OF THESE CONDITIONS.
* MEDIUM-HIGH CONFIDENCE IN MVFR CIGS CONTINUING THROUGH TONIGHT.
LOW CONFIDENCE IN IF THERE WILL BE ANY BREAKS TO VFR.
* HIGH CONFIDENCE IN WIND DIRECTION FORECAST AND SPEED
TRENDS...MEDIUM CONFIDENCE IN TIMING OF GUST DEVELOPMENT.
* HIGH CONFIDENCE IN SHRA ARRIVING LATER TODAY...MEDIUM-HIGH
CONFIDENCE IN TIMING. MEDIUM-HIGH CONFIDENCE THAT THERE WILL BE
AT LEAST SOME THUNDER IN THE AREA.
* MEDIUM CONFIDENCE IN LOW LEVEL WIND SHEAR SATURDAY EVENING BUT
SURFACE GUSTS MAY PRECLUDE IT.
MTF/MDB
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...BREEZY WEST WINDS DIMINISHING LATE.
MONDAY THROUGH WEDNESDAY...VFR.
THURSDAY AND FRIDAY...SLIGHT CHANCE SHRA DURING THE DAY AND RASN
AT NIGHT. MAINLY VFR.
MDB
&&
.MARINE...
354 AM CST
GALES THROUGH MONDAY AND A POTENTIAL PERIOD OF STORM FORCE WINDS
SUNDAY EVENING ARE THE FOCUS OF THIS FORECAST PERIOD. HIGH
PRESSURE REMAINS CENTERED OFF THE EAST COAST WITH EFFECTS OF THE
HIGH SPREAD BACK INTO THE EASTERN LAKES. LOW PRESSURE IS SPREAD
ACROSS THE PLAINS AND UPPER MIDWEST WITH CONSOLIDATION EXPECTED TO
OCCUR RESULTING IN A LOW TRACKING NORTHEAST TO WESTERN LAKE
SUPERIOR SUNDAY MORNING. THE PRESSURE GRADIENT WILL TIGHTEN AS
THIS LOW ORGANIZES ALLOWING SOUTH WINDS TO STEADILY INCREASE
ACROSS THE LAKE TODAY. WARMER AIR WILL BE MOVING INTO THE REGION
WHICH WILL CREATE SOME DEGREE OF A STABLE LAYER OVER THE LAKE
TODAY BUT GALES ARE STILL LIKELY TO DEVELOP THIS AFTERNOON AND
CONTINUE THIS EVENING. GALES WILL BE A BIT MORE MARGINAL IN THE
IL/IN NEARSHORE WATERS BUT OPTED TO HOIST A GALE WARNING FOR THESE
AREAS WITH 30 KT LIKELY AND DECENT POTENTIAL FOR GALE FORCE GUSTS
WITH QUITE A BIT OF WIND JUST ABOVE THE SURFACE...WITH BETTER
MIXING POSSIBLE THANKS TO AN OFFSHORE COMPONENT AT TIMES.
WINDS WILL EASE UP FOR A BRIEF PERIOD LATE TONIGHT AND EARLY
SUNDAY MORNING SO SPEEDS MAY FALL BELOW GALE FOR SEVERAL
HOURS...BUT WINDS WILL INCREASE AGAIN BY SUNDAY AFTERNOON AS A
STRONGER LOW EJECTS NORTHEAST FROM EASTERN COLORADO. THIS LOW WILL
RAPIDLY DEEPEN AS IT REACHES WISCONSIN AND THE EASTERN U.P. OF
MICHIGAN BY SUNDAY EVENING. MUCH WARMER AIR WILL BE DRAWN
NORTHWARD ACROSS THE LAKE BUT THE GRADIENT WILL BE TIGHT ENOUGH TO
SUPPORT GALES...EVEN IF MIXING IS VERY SHALLOW OVER THE COLDER
LAKE WATER. NEARSHORE AREAS MAY SEE THE STRONGEST WINDS DURING THE
DAY SUNDAY AS THE FLOW TURNS SOUTHWESTERLY AND WELL MIXED AIR
MOVES OFFSHORE. A FURTHER SHIFT TO WESTERLY WINDS WILL OCCUR AS
THE LOW FURTHER DEEPENS AND CONTINUES NORTHEAST DRAGGING A SHARP
COLD FRONT ACROSS THE LAKE BY SUNDAY EVENING. WITH THE DEEPENING
LOW AND UNSTABLE CONDITIONS DEVELOPING WINDS SHOULD INCREASE TO 45
KT WITH A DECENT POTENTIAL FOR 50 KT STORM FORCE WINDS SUNDAY
EVENING AND EARLY SUNDAY NIGHT. HAVE DECIDED TO EXTEND THE GALE
WARNING FROM LATE TONIGHT THROUGH MONDAY AFTERNOON AND EXPAND INTO
THE NEARSHORE WATERS...WITH AN EARLIER END TIME. WILL NEED TO KEEP
AN EYE ON THE DURATION OF ANY LULL PERIOD EARLY SUNDAY WHICH MAY
ALLOW FOR A SHORT WINDOW WITHOUT A GALE BUT AT THIS POINT THE
WINDOW LOOKS RATHER SHORT...ON THE ORDER OF 6-9 HOURS. STILL DO
HAVE SOME UNCERTAINTY ON THE TRACK OF THE LOW...WHETHER IT CROSSES
THE NORTHERN PART OF THE LAKE OR REMAINS JUST TO THE WEST AND
NORTH. RIGHT NOW PREFER THE WESTERN TRACK WHICH WOULD PROVIDE A
CLEANER SOUTHWEST TO WEST SHIFT OF THE WINDS AS OPPOSED THE
EASTERLY TRACK WHICH WOULD RESULT IN A BRIEF PERIOD OF NORTHERLY
WINDS OVER THE NORTHERN SECTIONS OF THE LAKE. WILL NEED TO KEEP AN
EYE ON THIS.
OTHERWISE WINDS WILL SLOWLY DIMINISH MONDAY AS HIGH PRESSURE
PASSES TO THE SOUTH AND EAST OF THE LAKE. LOW PRESSURE IS THEN
EXPECTED TO CROSS THE CANADIAN PRAIRIES TO JAMES BAY DURING THE
MIDDLE OF NEXT WEEK BRINGING ANOTHER INCREASE IN SOUTH WINDS WHICH
WILL FLIP NORTHWEST WITH A COLD FRONTAL PASSAGE LATER THURSDAY.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL NOON SATURDAY.
GALE WARNING...NEARSHORE WATERS UNTIL 4
AM MONDAY.
GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 PM MONDAY.
&&
$$
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...UPDATED
NWS CHICAGO/ROMEOVILLE IL
819 AM CST SAT NOV 16 2013
.DISCUSSION...
815 AM CST
FORECAST UPDATED TO ADD DRIZZLE IN THROUGH THIS MORNING.
THE LOW-LEVEL MOISTURE SURGE CONTINUES TO RETURN OVER THE AREA.
ISENTROPIC ASCENT ON THE RAP ANALYSIS OF 285K AND 290K SURFACES
HAS RAPIDLY SATURATED AND LOOKS TO BE THE ROOT OF THIS. EVEN ON
THE 12Z ILX RAOB...THE PROFILE WAS VERY SUGGESTIVE OF DRIZZLE.
THIS COULD CONTINUE INTO THIS AFTERNOON BASED ON THE EXTENT OF
UPSTREAM OBS ACROSS CENTRAL AND SOUTHERN IL. SOUTH WINDS CONTINUE
TO BRING WARM AIR ADVECTION SO TEMPERATURES WILL INCH UPWARD. THE
CHANCE FOR TRUE SHOWERS AND POSSIBLY SOME STORMS TODAY STILL LOOKS
TO ARRIVE WITH A SHORT WAVE ACROSS THE WESTERN FORECAST AREA BY
EARLY AFTERNOON AND SPREADING EAST FROM THERE.
MTF
&&
.PREV DISCUSSION...
333 AM...FORECAST FOCUS REMAINS POTENTIAL SEVERE WEATHER OUTBREAK
ACROSS THE SOUTHERN LAKES AND OHIO VALLEY ON SUNDAY.
IN THE SHORT TERM...LOW CLOUDS HAVE STREAMED NORTH ACROSS THE AREA
SIGNALING THE BEGINNING OF A SURGE OF LOW LEVEL MOISTURE.
DEWPOINTS SLOWLY CREEPING INTO THE LOWER 40S EARLY THIS MORNING
WILL CONTINUE TO RISE INTO THE LOWER/MID 50S THIS AFTERNOON...UPPER
50S TONIGHT AND LIKELY POOL IN THE LOWER TO PERHAPS MID 60S JUST
AHEAD OF THE COLD FRONT SUNDAY MORNING.
LOW PRESSURE OVER NEBRASKA WILL LIFT NORTH TO MINNESOTA BY THIS
EVENING AND AS IT DOES...AN UPPER LEVEL WAVE WILL MOVE ACROSS THE
AREA THIS AFTERNOON INTO THIS EVENING. MUCH OF THE EASTERN HALF OR
TWO THIRDS WILL LIKELY REMAIN DRY THIS MORNING WITH PRECIP
SPREADING ACROSS THE WESTERN CWA BY LATE MORNING. HAVE INCLUDED
JUST A CHANCE OF THUNDERSTORMS WITH THE STRONGER/CONVECTIVE
ELEMENTS BUT CONFIDENCE REGARDING HOW WIDESPREAD LIGHTNING/THUNDER
WILL BECOME IS SOMEWHAT LOW AND THUNDER COVERAGE MAY NEED TO BE
INCREASED BASED ON SHORT TERM TRENDS ONCE PRECIP DEVELOPS/ARRIVES.
THIS ACTIVITY SHOULD MOVE NORTHEAST OF THE AREA BY MID/LATE EVENING
WITH A POSSIBLE LULL IN ACTIVITY INTO THE EARLY MORNING HOURS. NOT
EXPECTING ANY OF THE THUNDERSTORMS DURING THIS FIRST WAVE TO BE
SEVERE. SOME COULD PRODUCE STRONG/GUSTY WINDS AS WELL AS HEAVY
RAIN. THOUGH STORM MOTION SHOULD BE SUFFICIENTLY FAST TO PREVENT A
LONG DURATION HEAVY RAIN IN ANY ONE LOCATION. RAINFALL AMOUNTS
WITH THIS WAVE APPEAR TO BE IN THE 0.5 TO 0.75 RANGE.
DESPITE MAINLY CLOUDY SKIES TODAY AND THEN PRECIP THIS
AFTERNOON...WITH THE NOTED SURGE IN LOW LEVEL MOISTURE...TEMPS
WILL CONTINUE TO CLIMB THROUGH THE DAY WITH CURRENT TEMPS ALREADY
IN THE LOWER 50S ACROSS SOUTHERN IL. THUS...HIGHS IN THE UPPER 50S
TO LOWER 60S LOOK ON TRACK AND MUCH OF THE SOUTHERN THIRD/HALF OF
THE CWA MAY NOT SEE PRECIP UNTIL LATE THIS AFTERNOON AND IF ANY
BREAKS DEVELOP...THIS WILL AID TEMPS FURTHER. AS PRECIP ENDS THIS
EVENING...POSSIBLE FOR SOME LOCATIONS...ESPECIALLY NORTHERN
CWA...TO CONTINUE TO WARM WITH HIGHS BEING REACHED IN THE EVENING.
A SECOND LOW THEN DEVELOPS OVER EASTERN COLORADO TONIGHT AND
QUICKLY SHIFTS EAST TO IOWA BY SUNDAY MORNING...THEN RAPIDLY
DEEPENS AS IT ABSORBS THE FIRST LOW OVER MINNESOTA...AND REACHES
LAKE SUPERIOR BY SUNDAY EVENING. A STRONG COLD FRONT WILL RACE
ACROSS THE CWA FROM MID/LATE SUNDAY MORNING THROUGH EARLY/MID
SUNDAY AFTERNOON. ANOTHER WAVE OF THUNDERSTORMS IS POSSIBLE IN THE
EARLY MORNING HOURS OF SUNDAY AHEAD OF THIS SECOND LOW...
DEVELOPING OVER EASTERN IOWA AND NORTHWEST IL THEN MOVING INTO
SOUTHERN WI...MOSTLY LIKELY BY SUNRISE. AT THE SAME TIME...
ADDITIONAL THUNDERSTORMS COULD BE DEVELOPING AHEAD OF THE COLD
FRONT ACROSS PARTS OF IOWA/MISSOURI. ANY OF THESE THUNDERSTORMS
OVERNIGHT INTO EARLY SUNDAY MORNING COULD BECOME SEVERE. BUT TO
WHAT EXTENT AND HOW WIDESPREAD ANY SEVERE WEATHER WOULD BECOME IS
UNCERTAIN. HOWEVER...WITH SUCH WARM/MOIST LOW LEVELS...A DEEPENING
SURFACE LOW AND WHAT COULD END UP BEING A WARM FRONTAL BOUNDARY
ACROSS THE NORTHERN CWA...THE THREAT OF A TORNADO WITH ANY STRONG
STORMS CAN/T BE RULED OUT.
ANOTHER BRIEF LULL IS EXPECTED SUNDAY MORNING BEFORE WHAT APPEARS
LIKE IT COULD BE THE BEGINNING OF A WIDESPREAD SEVERE WEATHER
OUTBREAK DEVELOPS. WINDS THROUGH THE ENTIRE COLUMN REMAIN VERY
IMPRESSIVE WITH 50 KNOTS AS LOW AS 900MB SUNDAY MORNING. AS
NOTED...WHILE THE WARM/MOIST CONDITIONS WILL HELP/AID STORMS
STAYING SURFACE BASED...EXPECT QUITE A BIT OF CLOUD COVER...AND
WHILE HAVE TRIED TO SHOW SOME PARTLY/MOSTLY CLOUDY CONDITIONS AT
LEAST ACROSS THE SOUTHEAST CWA SUNDAY MORNING...ITS POSSIBLE
OVERCAST CONDITIONS WILL PERSIST UNTIL FROPA. ADDITIONAL
UNCERTAINTY REMAINS WITH WHERE/WHEN THUNDERSTORMS WILL DEVELOP...
JUST WEST OF THE CWA...OVER THE CWA...EASTERN CWA/NORTHWEST
INDIANA. ENTIRE CWA IS NOW INCLUDED IN SLIGHT RISK PER THIS
MORNING/S SPC DAY2 OUTLOOK WITH MODERATE RISK EAST OF THE
I-55/I-57 CORRIDOR. POTENTIAL IS CERTAINLY HIGHER OVER THE EASTERN
CWA BUT EVEN FROM THIS DISTANCE WILL BE INCLUDING SEVERE
MENTION/DAMAGING WINDS IN THE ZONES/GRIDS. THUNDERSTORMS WILL BE
ENDING FROM WEST TO EAST DURING THE MID/LATE AFTERNOON AND ALSO
ATTEMPTED TO INCLUDE THIS TIMING IN THE GRIDS. THE THREAT OF A
TORNADO OR TWO WILL REMAIN SUNDAY BUT DAMAGING WINDS APPEAR TO BE
THE PRIMARY SEVERE WEATHER THREAT. DESPITE PRECIPITABLE WATER
VALUES ONLY AROUND AN INCH...EXPECT VERY EFFICIENT RAIN PRODUCTION
WITH ANOTHER 0.5-0.75 INCHES POSSIBLE...ALTHOUGH PERHAPS MORE
LOCALIZED DEPENDING ON CONVECTIVE COVERAGE.
STRONG WINDS FROM THE SOUTH WILL DEVELOP TODAY WITH GUSTS INTO THE
30-35 MPH RANGE POSSIBLE. STILL APPEARS THERE COULD BE A 3-6 HOUR
WINDOW THIS EVENING OF GUSTS 40+ MPH BEFORE WINDS DIMINISH SOME
OVERNIGHT...WHILE CLOSE TO WIND ADVISORY CRITERIA...NOT SURE IT
WILL BE REACHED AND NO HEADLINES THROUGH TONIGHT. BY SUNDAY...
LOW LEVEL WINDS ARE WELL INTO ADVISORY CRITERIA AND SOME OF THIS
WILL LIKELY MIX TO THE SURFACE ESPECIALLY JUST BEHIND THE STORMS/
COLD FRONT AS COLD ADVECTION IS AIDED BY LARGE PRESSURE RISES.
THIS IS THIRD PERIOD AND A BIT EARLY FOR AN ADVISORY AND LATER
SHIFTS WILL NEED TO ASSESS WIND POTENTIAL/HEADLINES FOR SUNDAY.
HAVE CONTINUED INCREASING HIGH TEMPS FOR SUNDAY WITH MID 60S NORTH
TO UPPER 60S FROM I-55 SOUTH AND ITS QUITE POSSIBLE SOME AREAS MAY
SEE TEMPS TAG 70 AHEAD OF THE FRONT...ESPECIALLY WITH ANY BREAKS
IN THE OVERCAST AS 850MB TEMPS ARE NOW EXPECTED TO BE IN THE +12C
TO +15C RANGE.
WRAP AROUND SHOWERS WILL BE POSSIBLE SUNDAY EVENING BUT SHOULD BE
ENDING FAIRLY QUICKLY WITH CLEARING SKIES OVERNIGHT AS HIGH
PRESSURE BUILDS INTO THE REGION MONDAY AFTERNOON/MONDAY NIGHT AND
THIS HIGH IS MOVING FASTER THAN PREVIOUS MODELS HAD SUGGESTED.
WHILE IT WILL TURN MUCH COLDER MONDAY NIGHT WITH LOWS IN THE 30S...
MONDAY MAY END UP BEING MAINLY SUNNY WITH DIMINISHING WINDS IN THE
AFTERNOON AND TEMPS REBOUNDING BACK INTO THE MID 40S. STILL WILL
FEEL MUCH COLDER COMPARED TO SUNDAY...BUT THE TREND IS SLIGHTLY
WARMER.
HAVE CONTINUED THE WARMING TREND TUESDAY THROUGH THURSDAY AS WINDS
TURN SOUTHERLY SOONER ON THE BACK SIDE OF THE DEPARTING HIGH. ALSO
NOW APPEARS THE CHANCE OF SHOWERS WILL ARRIVE SOONER...PERHAPS AS
EARLY AS LATE WEDNESDAY BUT CERTAINLY WEDNESDAY NIGHT INTO
THURSDAY. WARMING TEMPS DURING THIS PERIOD WITH SOUTHERLY FLOW
SHOULD KEEP PRECIP MAINLY LIQUID. A COLD FRONT THEN MOVES SOUTH
THURSDAY NIGHT AND FRIDAY WITH THE ECMWF MUCH COLDER THAN THE GFS
AND HAVE LOWERED TEMPS A FEW DEGREES DURING THIS TIME PERIOD AND
WHILE ITS STILL SEVERAL DAYS AWAY...POTENTIAL FOR SOME FROZEN
PRECIP EXISTS LATER FRIDAY/FRIDAY NIGHT...DEPENDING ON SPEED OF
FRONT AND END TIME OF PRECIP. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* DRIZZLE AND IFR CONDITIONS THIS MORNING...WITH EVEN A CHANCE OF
TEMPORARY LIFR.
* MVFR CIGS LIKELY WITH A CHANCE OF IFR CIGS TONIGHT.
* SOUTH WINDS INCREASING THROUGH THE MORNING WITH GUSTS 25-30 KT
THIS AFTERNOON. SOUTH TO SOUTHWEST WIND GUSTS IN EXCESS OF 30 KT
EXPECTED SUNDAY.
* SHRA EXPECTED LATE THIS AFTERNOON THROUGH THE EVENING WITH
THUNDER POSSIBLE. ADDITIONAL LOWER SHRA/TSRA CHANCES OVERNIGHT
WITH AN INCREASING CHANCE AFTER DAYBREAK SUNDAY.
* LOW LEVEL WIND SHEAR POSSIBLE AS WINDS NEAR 1500 FT INCREASE TO
50 KT.
MTF/MDB
//DISCUSSION...UPDATED 14Z...
TAFS HAVE BEEN UPDATED TO INCLUDE MORE PESSIMISTIC CONDITIONS THIS
MORNING DUE TO DRIZZLE AND IFR VISIBLITIES. IFR CONDITIONS EXIST
WELL UPSTREAM ACROSS CENTRAL IL SO MAY NEED TO EXTEND DURATION
INTO THE AFTERNOON. THERE HAVE BEEN TEMPORARY LIFR CONDITIONS
OBSERVED AT SOME AIRPORTS AND POSSIBLE THIS IS SEEN AT SOME OF THE
TAF SITES THROUGH EARLY AFTERNOON.
PREV DISCUSSION...UPDATED 12Z...
LOW PRESSURE IS ORGANIZING ACROSS THE CENTRAL AND NORTHERN PLAINS
AND WILL MOVE NORTHEAST TO LAKE SUPERIOR TONIGHT. INCREASING
SOUTHERLY FLOW HAS BROUGHT AN INFLUX OF STRATUS AND SOME MIST TO
THE TERMINALS OVERNIGHT. SEVERAL SITES HAD DIPPED TO IFR BUT HAVE
BEEN SEEING IMPROVEMENT UPSTREAM OVER THE LAST HOUR OR TWO. EXPECT
THE IFR CIGS/VSBY TO IMPROVE WITH A STEADIER MVFR CLOUD DECK
BECOMING ESTABLISHED THROUGH THE MORNING...LIKELY IN THE 1000-2000
FT RANGE. MVFR LOOKS TO CONTINUE THROUGH THE NIGHT...THOUGH THERE
MAY BE SOME BREAKS AT TIMES LATER TODAY AND TONIGHT BUT CONFIDENCE
IN DETAILS IS LOW. WINDS WILL BE INCREASING THROUGH THE MORNING
WITH GUSTS BECOMING MORE FREQUENT INTO THE AFTERNOON AS GUSTS
SPEEDS PUSH 25 TO 30 KT. AN UPPER LEVEL TROUGH WILL CROSS THE AREA
LATE THIS AFTERNOON AND THIS EVENING BRINGING SHOWERS WITH IT AS
WELL AS AT LEAST A CHANCE FOR THUNDER. HAVE DECENT CONFIDENCE IN
THUNDER OCCURRING THOUGH TI MAY NIT IMPACT EACH TERMINAL DIRECTLY.
THERE LOOKS TO BE A LULL IN THE PRECIP LATER THIS EVENING AND
EARLY TONIGHT BEFORE CHANCE INCREASE EARLY SUNDAY MORNING AS
ANOTHER PUSH OF WARMER AIR STREAMS OVER. CIGS MAY LOWER TO IFR
OVERNIGHT BUT WILL JUST HINT AT IT WITH SCT IFR LEVEL CLOUD
MENTION FOR NOW. WIND GUSTS SHOULD CONTINUE THROUGH THE EVENING
AND MAY EVEN INCREASE. RAIN.THUNDER COVERAGE AND TIMING IS
SOMEWHAT UNCERTAIN GOING INTO SUNDAY MORNING BUT CHANCES WILL
LIKELY INCREASE UNTIL A COLD FRONT CROSSES THE AREA IN CONJUNCTION
WITH A SECOND AND MORE INTENSE LOW PRESSURE AREA MOVING NORTH OF
THE AREA. SOUTH TO SOUTHWEST WINDS WILL INCREASE SUNDAY MORNING
AND GUSTS IN EXCESS OF 35 KT A GOOD POSSIBILITY...WITH THE
DIRECTION TURNING MORE WESTERLY THROUGH THE DAY.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* HIGH CONFIDENCE IN IFR CONDITIONS THIS MORNING WITH AT LEAST
TEMPORARY SUB 700 FT CIGS AND <3SM VISIBILITY. LOW CONFIDENCE IN
DURATION OF THESE CONDITIONS.
* MEDIUM-HIGH CONFIDENCE IN MVFR CIGS CONTINUING THROUGH TONIGHT.
LOW CONFIDENCE IN IF THERE WILL BE ANY BREAKS TO VFR.
* HIGH CONFIDENCE IN WIND DIRECTION FORECAST AND SPEED
TRENDS...MEDIUM CONFIDENCE IN TIMING OF GUST DEVELOPMENT.
* HIGH CONFIDENCE IN SHRA ARRIVING LATER TODAY...MEDIUM-HIGH
CONFIDENCE IN TIMING. MEDIUM-HIGH CONFIDENCE THAT THERE WILL BE
AT LEAST SOME THUNDER IN THE AREA.
* MEDIUM CONFIDENCE IN LOW LEVEL WIND SHEAR SATURDAY EVENING BUT
SURFACE GUSTS MAY PRECLUDE IT.
MTF/MDB
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...BREEZY WEST WINDS DIMINISHING LATE.
MONDAY THROUGH WEDNESDAY...VFR.
THURSDAY AND FRIDAY...SLIGHT CHANCE SHRA DURING THE DAY AND RASN
AT NIGHT. MAINLY VFR.
MDB
&&
.MARINE...
354 AM CST
GALES THROUGH MONDAY AND A POTENTIAL PERIOD OF STORM FORCE WINDS
SUNDAY EVENING ARE THE FOCUS OF THIS FORECAST PERIOD. HIGH
PRESSURE REMAINS CENTERED OFF THE EAST COAST WITH EFFECTS OF THE
HIGH SPREAD BACK INTO THE EASTERN LAKES. LOW PRESSURE IS SPREAD
ACROSS THE PLAINS AND UPPER MIDWEST WITH CONSOLIDATION EXPECTED TO
OCCUR RESULTING IN A LOW TRACKING NORTHEAST TO WESTERN LAKE
SUPERIOR SUNDAY MORNING. THE PRESSURE GRADIENT WILL TIGHTEN AS
THIS LOW ORGANIZES ALLOWING SOUTH WINDS TO STEADILY INCREASE
ACROSS THE LAKE TODAY. WARMER AIR WILL BE MOVING INTO THE REGION
WHICH WILL CREATE SOME DEGREE OF A STABLE LAYER OVER THE LAKE
TODAY BUT GALES ARE STILL LIKELY TO DEVELOP THIS AFTERNOON AND
CONTINUE THIS EVENING. GALES WILL BE A BIT MORE MARGINAL IN THE
IL/IN NEARSHORE WATERS BUT OPTED TO HOIST A GALE WARNING FOR THESE
AREAS WITH 30 KT LIKELY AND DECENT POTENTIAL FOR GALE FORCE GUSTS
WITH QUITE A BIT OF WIND JUST ABOVE THE SURFACE...WITH BETTER
MIXING POSSIBLE THANKS TO AN OFFSHORE COMPONENT AT TIMES.
WINDS WILL EASE UP FOR A BRIEF PERIOD LATE TONIGHT AND EARLY
SUNDAY MORNING SO SPEEDS MAY FALL BELOW GALE FOR SEVERAL
HOURS...BUT WINDS WILL INCREASE AGAIN BY SUNDAY AFTERNOON AS A
STRONGER LOW EJECTS NORTHEAST FROM EASTERN COLORADO. THIS LOW WILL
RAPIDLY DEEPEN AS IT REACHES WISCONSIN AND THE EASTERN U.P. OF
MICHIGAN BY SUNDAY EVENING. MUCH WARMER AIR WILL BE DRAWN
NORTHWARD ACROSS THE LAKE BUT THE GRADIENT WILL BE TIGHT ENOUGH TO
SUPPORT GALES...EVEN IF MIXING IS VERY SHALLOW OVER THE COLDER
LAKE WATER. NEARSHORE AREAS MAY SEE THE STRONGEST WINDS DURING THE
DAY SUNDAY AS THE FLOW TURNS SOUTHWESTERLY AND WELL MIXED AIR
MOVES OFFSHORE. A FURTHER SHIFT TO WESTERLY WINDS WILL OCCUR AS
THE LOW FURTHER DEEPENS AND CONTINUES NORTHEAST DRAGGING A SHARP
COLD FRONT ACROSS THE LAKE BY SUNDAY EVENING. WITH THE DEEPENING
LOW AND UNSTABLE CONDITIONS DEVELOPING WINDS SHOULD INCREASE TO 45
KT WITH A DECENT POTENTIAL FOR 50 KT STORM FORCE WINDS SUNDAY
EVENING AND EARLY SUNDAY NIGHT. HAVE DECIDED TO EXTEND THE GALE
WARNING FROM LATE TONIGHT THROUGH MONDAY AFTERNOON AND EXPAND INTO
THE NEARSHORE WATERS...WITH AN EARLIER END TIME. WILL NEED TO KEEP
AN EYE ON THE DURATION OF ANY LULL PERIOD EARLY SUNDAY WHICH MAY
ALLOW FOR A SHORT WINDOW WITHOUT A GALE BUT AT THIS POINT THE
WINDOW LOOKS RATHER SHORT...ON THE ORDER OF 6-9 HOURS. STILL DO
HAVE SOME UNCERTAINTY ON THE TRACK OF THE LOW...WHETHER IT CROSSES
THE NORTHERN PART OF THE LAKE OR REMAINS JUST TO THE WEST AND
NORTH. RIGHT NOW PREFER THE WESTERN TRACK WHICH WOULD PROVIDE A
CLEANER SOUTHWEST TO WEST SHIFT OF THE WINDS AS OPPOSED THE
EASTERLY TRACK WHICH WOULD RESULT IN A BRIEF PERIOD OF NORTHERLY
WINDS OVER THE NORTHERN SECTIONS OF THE LAKE. WILL NEED TO KEEP AN
EYE ON THIS.
OTHERWISE WINDS WILL SLOWLY DIMINISH MONDAY AS HIGH PRESSURE
PASSES TO THE SOUTH AND EAST OF THE LAKE. LOW PRESSURE IS THEN
EXPECTED TO CROSS THE CANADIAN PRAIRIES TO JAMES BAY DURING THE
MIDDLE OF NEXT WEEK BRINGING ANOTHER INCREASE IN SOUTH WINDS WHICH
WILL FLIP NORTHWEST WITH A COLD FRONTAL PASSAGE LATER THURSDAY.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL NOON SATURDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...NOON
SATURDAY TO 4 AM MONDAY.
GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...NOON SATURDAY TO 3 PM
MONDAY.
&&
$$
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AREA FORECAST DISCUSSION...UPDATED
NWS TOPEKA KS
1136 PM CST Fri Nov 15 2013
...Update to aviation forecast discussion...
.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 06Z TAFs through 06Z Saturday Night)
Issued at 1128 PM CST FRI NOV 15 2013
Stratus now developing over eastern OK should spread/develop
northward into the Taf sites in the 08Z-11z time frame with mvfr
cigs (IFR at KFOE) as gusty south winds continue. Cigs should
gradually scatter to vfr aft 14z at KMHK with vfr conditions not
working into the KTOP/KFOE until 18z. Also may be some patchy
drizzle as well. Otherwise expect most precip to remain south and
east of the TAF sites through the fcst...with gusty
south/southwest winds of 20-30 gusts to 35kts decreasing aft 23Z.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Barjenbruch
LONG TERM...Sanders
AVIATION...63
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
952 PM EST SUN NOV 17 2013
.SYNOPSIS...
HIGH PRESSURE EAST OF NEW ENGLAND WILL SLIDE TO THE EAST. DEEPENING
LOW PRESSURE OVER THE WESTERN GREAT LAKES WILL MOVE NORTHEAST INTO
CANADA...PUSHING A COLD FRONT ACROSS THE LOCAL AREA EARLY MONDAY.
HIGH PRESSURE THEN RETURNS FOR THE MIDDLE OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
SURFACE ANALYSIS SHOWS A ~980MB LOW JUST NORTH OF LAKE SUPERIOR IN
SOUTHERN ONTARIO, WITH A STRONG COLD FRONT SOUTH THROUGH EASTERN
ILLINOIS TO NORTHEAST TEXAS. ALOFT, MID EVENING WATER VAPOR SAT
IMAGERY SHOWING NEGATIVELY TILTED SHORT WAVE TROUGH PUSHING E-NE
FROM THE MID MISSOURI VALLEY TOWARDS THE UPPER MIDWEST.
RADAR MOSAIC INDICATES A BATCH OF LIGHT RAIN ACROSS SOUTHWEST
VIRGINIA.
A WEAK AREA OF SUBTLE UPPER VORT/WEAK LIFT HAS ALLOWED SOME
SCATTERED SHOWERS/SPRINKLES TO CROP UP IN THE WARM SECTOR THIS
EVENING. HAVE REORGANIZED POPS SLIGHTLY AND WILL GO WITH ISO/SCT
SHRA WORDING EARLY THIS EVENING. HRRR HAS HANDLED RADAR TRENDS
REASONABLY WELL THIS EVENING...WITH ITS SOLUTION KEEPING AREAL
COVERAGE OF SHRAS RATHER SPOTTY THROUGH MUCH OF THE NIGHT. THIS
DOES MAKE SENSE GIVEN RATHER ANEMIC FORCING WITH PRE-FRONTAL PCPN.
SHOWERS DO INCREASE IN COVERAGE LATE W/AFOREMENTIONED COLD FRONT
DROPPING INTO THE NW CORNER OF THE CWA AROUND 09Z. A NARROW LINE
OF SHOWERS LOOKS TO ACCOMPANY THE FRONT...MOST LIKELY WITH BEST
FORCING/CONVERGENCE OVER THE NORTHERN HALF OF THE AREA. HAVE
LIKELY POPS OVER THIS AREA WITH THE FRONTAL PASSAGE...WITH HIGH
CHC POPS FARTHER SOUTH. FRONT SWEEPS QUICKLY TO THE EAST, WITH
DRYING ALOFT QUICKLY BRINGING AN END TO PCPN BEHIND THE FRONT. BY
12Z...THE FRONT WILL EXTEND FROM THE EASTERN PART OF THE NORTHERN
NECK THROUGH THE RICHMOND METRO AREA AND INTO NORTH CENTRAL NC.
PRE-FRONTAL S/SW WINDS WL INCREASE OVER THE NEXT FEW HRS, KEEPING
TEMPERATURES ON THE MILD SIDE. DESPITE STRONG SHEAR...KEPT TSTMS
OUT OF THE FCST. CAPE WILL BE VERY LIMITED AND THE SURFACE WILL
REMAIN STABLE. A FEW GUSTS TO AROUND 30 MPH WILL BE PSBL NEAR THE
FRONT AND ASSOCIATED SHOWERS.
TEMPERATURES HAVE LEVELED OFF THIS EVENING...AND EXPECT STEADY
TEMPS TO RISE SLIGHTLY OVERNIGHT AHEAD OF THE FRONT. EARLY
MORNING LOW TEMPERATURES TO RANGE FROM 60 TO 65...WITH UPR 50S
BEHIND THE FRONT OVER LOUISA AND FLUVANNA COUNTIES.
ON MONDAY...THE FRONT MOVES OFF THE COAST AROUND MIDDAY. PCPN ENDS
IN MOST AREAS IN THE MRNG BUT KEPT SLGT CHC POPS ON THE NC COAST
THROUGH 20Z. DOWNSLOPE FLOW SHOULD BRING SUNSHINE BEHIND THE FRONT
ACROSS THE WESTERN CWA...AND ALLOW TEMPERATURES TO BE MILD ON
MONDAY. EXPECT MAXIMA IN THE LOW TO MID 70S ACROSS MOST OF THE AREA
EXCEPT NEAR 70 WEST OF INTERSTATE 95. TEMPERATURES WILL BEGIN TO
FALL DURING THE AFTN OVER WESTERN SECTIONS. WINDS WILL BE BREEZY
FROM THE WEST AND NORTHWEST...ESPECIALLY NEAR THE COAST.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
MONDAY NIGHT THROUGH TUESDAY NIGHT IS STRAIGHTFORWARD WITH DRY
CONDITIONS AND A MOSTLY CLEAR SKY. HIGH PRESSURE WILL BE OVER THE
NORTHEASTERN STATES WITH RIDGING INTO THE MID ATLANTIC. THE CORE OF
THE RIDGE WILL BE OVERHEAD TUESDAY WHICH WILL REDUCE MIXING SOME.
MODELS ARE ALL OVER THE PLACE WITH HIGH TEMPERATURES BUT STAYED
CLOSE TO OUR PREVIOUS FORECAST AND MOS GUIDE. HIGH TEMPERATURES WILL
RANGE FROM 50 TO 55. ON WEDNESDAY...NE TO E FLOW WILL RESULT IN AN
INCREASE IN CLOUDS AND TEMPERATURES A BIT LOWER...ESPECIALLY OVER
THE PIEDMONT. READINGS ARE EXPECTED TO RANGE FROM AROUND 50 IN THE
PIEDMONT TO THE MID 50S IN NE NORTH CAROLINA. KEPT SLGT CHC FOR
SHOWERS FOR THE NC COAST WITH SOME MODEL SUPPORT...ESPECIALLY FROM
THE GFS FOR THIS POSSIBILITY. LOW TEMPERATURES TUESDAY AND
WEDNESDAY MORNINGS WILL GENERALLY RANGE FROM 30 TO 35.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE SHIFTS OFF THE NRN NEW ENGLAND COAST WED NIGHT AND
THU...THEN STARTS TO SLIDE DOWN THE ATLANTIC COAST THU NIGHT AND
FRI. THE PRESSURE GRADIENT WILL REMAIN TIGHT OVER SERN PORTIONS OF
THE REGION WED NIGHT...FOLLOWED BY ADDITIONAL RELAXING OF THE
GRADIENT IN THIS AREA BY THU AFTN. NW-N WINDS WILL REMAIN BREEZY
NEAR COASTAL AREAS WED THROUGH FRI DUE TO THE PERSISTENT ONSHORE
FLOW. AS WINDS BECOME MORE NE-E ON WED...EXPECT LOW CLOUDS TO MOVE
INTO COASTAL AREAS FROM THE OCEAN. THIS COULD RESULT IN LIGHT RAIN
SHOWERS AND OCCASIONAL DRIZZLE WED/THU. AN APPROACHING COLD FRONT
WILL BOOST TEMPS ACROSS THE REGION FRI/FRI NIGHT...FOLLOWED BY
ANOTHER POTENTIAL BLAST OF ARCTIC AIR SAT/SUN.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
A GUSTY S-SW WIND SHOULD DEVELOP THIS EVENING...WITH GUSTS TO
20-25KT POSSIBLE DURING THE EARLY OVERNIGHT HOURS. MODELS REMAIN
CONSISTENT BRINGING A BAND OF SHRA AND ASSOCIATED MVFR CONDITIONS
ACROSS THE REGION FROM NW TO SE IN THE 07-15Z TIMEFRAME AHEAD OF A
COLD FRONT. THE COLD FRONT SWEEPS THROUGH THE REGION MONDAY
MORNING. DRIER AIR RETURNS FROM THE WEST LATER MONDAY INTO TUESDAY
AS HIGH PRESSURE BUILDS IN FROM THE NW.
&&
.MARINE...
WEAK HIGH PRESSURE CONTINUES TO BREAKDOWN THIS EVENING AS E-SE WINDS
REMAIN AOB 10 KT WITH SEAS AVERAGING 1-3 FT. THIS ALL CHANGES
OVERNIGHT AS A VERY STRONG COLD FRONT APPROACHES THE
REGION...CAUSING THE SFC PRESSURE GRADIENT TO TIGHTEN AND THE WINDS
TO VEER TO THE S. WINDS SHIFT TO THE SW AND QUICKLY INCREASE INTO
LOW-END SCA THRESHOLDS JUST AHEAD OF AND ALONG THE FRONTAL PASSAGE
DURING THE PRE-DAWN AND EARLY DAYLIGHT HOURS MON MORNING. SPEEDS
OF 20-25 KT BAY/COASTAL WATERS AND 15-20 KT CURRITUCK SOUND SHOULD
BE ANTICIPATED DURING THE AFOREMENTIONED TIMEFRAME. WAVES ON CHES
BAY WILL QUICKLY BUILD TO 3-4 FT WHILE SEAS QUICKLY RESPOND AND JUMP
TO 4-6 FT FOR ALL COASTAL WATERS (UP TO 7 FT NEAR 20 NM FROM FENWICK
ISLAND TO CHINCOTEAGUE). SW WINDS TURN TO THE W-NW BEHIND THE
FRONTAL PASSAGE ON MON AND SPEEDS WILL DIMINISH BELOW SCA THRESHOLDS
DURING THE DAYTIME. THIS WILL BE SHORT-LIVED AS COLDER TEMPERATURES
FROM A MODIFIED ARCTIC AIRMASS MOVE OVER THE WATERS EARLY MON
EVENING THROUGH TUE. THIS PARTICULAR SET-UP WILL RESULT IN A NW-N
SURGE BEGINNING MON NIGHT AND CONTINUING THROUGH TUE NIGHT BEFORE
WINDS BEGIN TO DIMINISH ON WED. EXPECT THE STRONGEST SURGE TO OCCUR
EARLY TUE MORNING WHEN THE WIND DIRECTION TURNS FROM NW TO N. WIND
SPEEDS ARE ANTICIPATED TO INCREASE TO 20-25 KT (SOLID SCA
CONDITIONS) OVER ALL WATERS...WITH GUSTS TO AROUND 30 KT. RESPONDING
WAVES ARE EXPECTED TO REBUILD TO 4-5 FT OVER CHES BAY. SEAS ARE ALSO
EXPECTED TO BUILD FROM 3-4 FT MONDAY EVENING TO 5-6 FT EARLY TUE
MORNING. PREVIOUS FLAGS FOR COASTAL WATERS NORTH OF THE VA/NC BORDER
AND CHES BAY HAVE BEEN EXTENDED THROUGH TUESDAY EVENING...DESPITE
THE LULL IN WINDS MON AFTN. ADDITIONAL FLAGS HAVE BEEN ISSUED FOR
SRN COASTAL WATERS FROM THE VA/NC BORDER TO CURRITUCK
LIGHT...CURRITUCK SOUND FOR TONIGHT THROUGH TUE EVENING. AN
ADDITIONAL SCA FLAG HAS BEEN ISSUED FOR THE LOWER JAMES RIVER FOR
LATE TONIGHT INTO MON MORNING. HEADLINES FOR REST OF ERN VA RIVERS
WILL LIKELY BE NEEDED FOR MON NIGHT INTO TUESDAY BUT WILL HOLD OFF
ON ISSUING THEM ATTM.
HIGH PRESSURE BEGINS TO SHIFT ACROSS THE OH VALLEY ON TUE...THEN
SHIFTS OVER NRN NEW ENGLAND TUE NIGHT THROUGH WED. THE PRESSURE
GRADIENT WILL REMAIN TIGHT OVER THE WATERS DURING THIS TIMEFRAME.
N WINDS WILL REMAIN ELEVATED IN LOW-END SCA WIND SPEEDS EARLY TUE
NIGHT...THEN START TO DIMINISH AFTER MIDNIGHT INTO WED. EXPECT
WINDS AFTER MIDNIGHT TO AOB 15 KT BAY/RIVERS/SOUND...AOB 20 KT
COASTAL WATERS. AS THE NRN NEW ENGLAND HIGH PRESSURE CENTER MOVES
ACROSS NRN NEW ENGLAND TO JUST OFF ITS COAST ON WED NIGHT INTO
THU...WINDS BECOME MORE NE-E/ONSHORE. SPEEDS WILL BEGIN TO SLACKEN
THROUGH WED AND DIMINISH FURTHER WED NIGHT INTO THU. WAVES ON CHES
BAY SHOULD START TO SUBSIDE BY WED AFTN...EXCEPT THE MOUTH OF THE
BAY WHERE ONSHORE WINDS WILL KEEP WAVES HIGHER THROUGH WED NIGHT.
SEAS SHOULD ALSO BE SLOW TO SUBSIDE BELOW 5 FT UNTIL SOMETIME THU
NIGHT/FRI. HIGH PRESSURE LINGERS OFF THE NRN NEW ENGLAND COAST
THROUGH FRI AND ONSHORE FLOW WILL PERSIST.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST TUESDAY FOR ANZ630>634-650-
652-654-656-658.
SMALL CRAFT ADVISORY UNTIL NOON EST MONDAY FOR ANZ638.
&&
$$
SYNOPSIS...LSA
NEAR TERM...MAM/LSA
SHORT TERM...LSA
LONG TERM...BMD
AVIATION...AJZ/DAP
MARINE...BMD
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
951 PM EST SUN NOV 17 2013
.SYNOPSIS...
HIGH PRESSURE EAST OF NEW ENGLAND WILL SLIDE TO THE EAST. DEEPENING
LOW PRESSURE OVER THE WESTERN GREAT LAKES WILL MOVE NORTHEAST INTO
CANADA...PUSHING A COLD FRONT ACROSS THE LOCAL AREA EARLY MONDAY.
HIGH PRESSURE THEN RETURNS FOR THE MIDDLE OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
SURFACE ANALYSIS SHOWS A ~980MB LOW JUST NORTH OF LAKE SUPERIOR IN
SOUTHERN ONTARIO, WITH A STRONG COLD FRONT SOUTH THROUGH EASTERN
ILLINOIS TO NORTHEAST TEXAS. ALOFT, MID EVENING WATER VAPOR SAT
IMAGERY SHOWING NEGATIVELY TILTED SHORT WAVE TROUGH PUSHING E-NE
FROM THE MID MISSOURI VALLEY TOWARDS THE UPPER MIDWEST.
RADAR MOSAIC INDICATES A BATCH OF LIGHT RAIN ACROSS SOUTHWEST
VIRGINIA.
A WEAK AREA OF SUBTLE UPPER VORT/WEAK LIFT HAS ALLOWED SOME
SCATTERED SHOWERS/SPRINKLES TO CROP UP IN THE WARM SECTOR THIS
EVENING. HAVE REORGANIZED POPS SLIGHTLY AND WILL GO WITH ISO/SCT
SHRA WORDING EARLY THIS EVENING. HRRR HAS HANDLED RADAR TRENDS
REASONABLY WELL THIS EVENING...WITH ITS SOLUTION KEEPING AREAL
COVERAGE OF SHRAS RATHER SPOTTY THROUGH MUCH OF THE NIGHT. THIS
DOES MAKE SENSE GIVEN RATHER ANEMIC FORCING WITH PRE-FRONTAL PCPN.
SHOWERS DO INCREASE IN COVERAGE LATE W/AFOREMENTIONED COLD FRONT
DROPPING INTO THE NW CORNER OF THE CWA AROUND 09Z. A NARROW LINE
OF SHOWERS LOOKS TO ACCOMPANY THE FRONT...MOST LIKELY WITH BEST
FORCING/CONVERGENCE OVER THE NORTHERN HALF OF THE AREA. HAVE
LIKELY POPS OVER THIS AREA WITH THE FRONTAL PASSAGE...WITH HIGH
CHC POPS FARTHER SOUTH. FRONT SWEEPS QUICKLY TO THE EAST, WITH
DRYING ALOFT QUICKLY BRINGING AN END TO PCPN BEHIND THE FRONT. BY
12Z...THE FRONT WILL EXTEND FROM THE EASTERN PART OF THE NORTHERN
NECK THROUGH THE RICHMOND METRO AREA AND INTO NORTH CENTRAL NC.
PRE-FRONTAL S/SW WINDS WL INCREASE OVER THE NEXT FEW HRS, KEEPING
TEMPERATURES ON THE MILD SIDE. DESPITE STRONG SHEAR...KEPT TSTMS
OUT OF THE FCST. CAPE WILL BE VERY LIMITED AND THE SURFACE WILL
REMAIN STABLE. A FEW GUSTS TO AROUND 30 MPH WILL BE PSBL NEAR THE
FRONT AND ASSOCIATED SHOWERS.
TEMPERATURES HAVE LEVELED OFF THIS EVENING...AND EXPECT STEADY
TEMPS TO RISE SLIGHTLY OVERNIGHT AHEAD OF THE FRONT. EARLY
MORNING LOW TEMPERATURES TO RANGE FROM 60 TO 65...WITH UPR 50S
BEHIND THE FRONT OVER LOUISA AND FLUVANNA COUNTIES.
ON MONDAY...THE FRONT MOVES OFF THE COAST AROUND MIDDAY. PCPN ENDS
IN MOST AREAS IN THE MRNG BUT KEPT SLGT CHC POPS ON THE NC COAST
THROUGH 20Z. DOWNSLOPE FLOW SHOULD BRING SUNSHINE BEHIND THE FRONT
ACROSS THE WESTERN CWA...AND ALLOW TEMPERATURES TO BE MILD ON
MONDAY. EXPECT MAXIMA IN THE LOW TO MID 70S ACROSS MOST OF THE AREA
EXCEPT NEAR 70 WEST OF INTERSTATE 95. TEMPERATURES WILL BEGIN TO
FALL DURING THE AFTN OVER WESTERN SECTIONS. WINDS WILL BE BREEZY
FROM THE WEST AND NORTHWEST...ESPECIALLY NEAR THE COAST.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
MONDAY NIGHT THROUGH TUESDAY NIGHT IS STRAIGHTFORWARD WITH DRY
CONDITIONS AND A MOSTLY CLEAR SKY. HIGH PRESSURE WILL BE OVER THE
NORTHEASTERN STATES WITH RIDGING INTO THE MID ATLANTIC. THE CORE OF
THE RIDGE WILL BE OVERHEAD TUESDAY WHICH WILL REDUCE MIXING SOME.
MODELS ARE ALL OVER THE PLACE WITH HIGH TEMPERATURES BUT STAYED
CLOSE TO OUR PREVIOUS FORECAST AND MOS GUIDE. HIGH TEMPERATURES WILL
RANGE FROM 50 TO 55. ON WEDNESDAY...NE TO E FLOW WILL RESULT IN AN
INCREASE IN CLOUDS AND TEMPERATURES A BIT LOWER...ESPECIALLY OVER
THE PIEDMONT. READINGS ARE EXPECTED TO RANGE FROM AROUND 50 IN THE
PIEDMONT TO THE MID 50S IN NE NORTH CAROLINA. KEPT SLGT CHC FOR
SHOWERS FOR THE NC COAST WITH SOME MODEL SUPPORT...ESPECIALLY FROM
THE GFS FOR THIS POSSIBILITY. LOW TEMPERATURES TUESDAY AND
WEDNESDAY MORNINGS WILL GENERALLY RANGE FROM 30 TO 35.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE SHIFTS OFF THE NRN NEW ENGLAND COAST WED NIGHT AND
THU...THEN STARTS TO SLIDE DOWN THE ATLANTIC COAST THU NIGHT AND
FRI. THE PRESSURE GRADIENT WILL REMAIN TIGHT OVER SERN PORTIONS OF
THE REGION WED NIGHT...FOLLOWED BY ADDITIONAL RELAXING OF THE
GRADIENT IN THIS AREA BY THU AFTN. NW-N WINDS WILL REMAIN BREEZY
NEAR COASTAL AREAS WED THROUGH FRI DUE TO THE PERSISTENT ONSHORE
FLOW. AS WINDS BECOME MORE NE-E ON WED...EXPECT LOW CLOUDS TO MOVE
INTO COASTAL AREAS FROM THE OCEAN. THIS COULD RESULT IN LIGHT RAIN
SHOWERS AND OCCASIONAL DRIZZLE WED/THU. AN APPROACHING COLD FRONT
WILL BOOST TEMPS ACROSS THE REGION FRI/FRI NIGHT...FOLLOWED BY
ANOTHER POTENTIAL BLAST OF ARCTIC AIR SAT/SUN.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
A GUSTY S-SW WIND SHOULD DEVELOP THIS EVENING...WITH GUSTS TO
20-25KT POSSIBLE DURING THE EARLY OVERNIGHT HOURS. MODELS REMAIN
CONSISTENT BRINGING A BAND OF SHRA AND ASSOCIATED MVFR CONDITIONS
ACROSS THE REGION FROM NW TO SE IN THE 07-15Z TIMEFRAME AHEAD OF A
COLD FRONT. THE COLD FRONT SWEEPS THROUGH THE REGION MONDAY
MORNING. DRIER AIR RETURNS FROM THE WEST LATER MONDAY INTO TUESDAY
AS HIGH PRESSURE BUILDS IN FROM THE NW.
&&
.MARINE...
WEAK HIGH PRESSURE CONTINUES TO BREAKDOWN THIS EVENING AS E-SE WINDS
REMAIN AOB 10 KT WITH SEAS AVERAGING 1-3 FT. THIS ALL CHANGES
OVERNIGHT AS A VERY STRONG COLD FRONT APPROACHES THE
REGION...CAUSING THE SFC PRESSURE GRADIENT TO TIGHTEN AND THE WINDS
TO VEER TO THE S. WINDS SHIFT TO THE SW AND QUICKLY INCREASE INTO
LOW-END SCA THRESHOLDS JUST AHEAD OF AND ALONG THE FRONTAL PASSAGE
DURING THE PRE-DAWN AND EARLY DAYLIGHT HOURS MON MORNING. SPEEDS
OF 20-25 KT BAY/COASTAL WATERS AND 15-20 KT CURRITUCK SOUND SHOULD
BE ANTICIPATED DURING THE AFOREMENTIONED TIMEFRAME. WAVES ON CHES
BAY WILL QUICKLY BUILD TO 3-4 FT WHILE SEAS QUICKLY RESPOND AND JUMP
TO 4-6 FT FOR ALL COASTAL WATERS (UP TO 7 FT NEAR 20 NM FROM FENWICK
ISLAND TO CHINCOTEAGUE). SW WINDS TURN TO THE W-NW BEHIND THE
FRONTAL PASSAGE ON MON AND SPEEDS WILL DIMINISH BELOW SCA THRESHOLDS
DURING THE DAYTIME. THIS WILL BE SHORT-LIVED AS COLDER TEMPERATURES
FROM A MODIFIED ARCTIC AIRMASS MOVE OVER THE WATERS EARLY MON
EVENING THROUGH TUE. THIS PARTICULAR SET-UP WILL RESULT IN A NW-N
SURGE BEGINNING MON NIGHT AND CONTINUING THROUGH TUE NIGHT BEFORE
WINDS BEGIN TO DIMINISH ON WED. EXPECT THE STRONGEST SURGE TO OCCUR
EARLY TUE MORNING WHEN THE WIND DIRECTION TURNS FROM NW TO N. WIND
SPEEDS ARE ANTICIPATED TO INCREASE TO 20-25 KT (SOLID SCA
CONDITIONS) OVER ALL WATERS...WITH GUSTS TO AROUND 30 KT. RESPONDING
WAVES ARE EXPECTED TO REBUILD TO 4-5 FT OVER CHES BAY. SEAS ARE ALSO
EXPECTED TO BUILD FROM 3-4 FT MONDAY EVENING TO 5-6 FT EARLY TUE
MORNING. PREVIOUS FLAGS FOR COASTAL WATERS NORTH OF THE VA/NC BORDER
AND CHES BAY HAVE BEEN EXTENDED THROUGH TUESDAY EVENING...DESPITE
THE LULL IN WINDS MON AFTN. ADDITIONAL FLAGS HAVE BEEN ISSUED FOR
SRN COASTAL WATERS FROM THE VA/NC BORDER TO CURRITUCK
LIGHT...CURRITUCK SOUND FOR TONIGHT THROUGH TUE EVENING. AN
ADDITIONAL SCA FLAG HAS BEEN ISSUED FOR THE LOWER JAMES RIVER FOR
LATE TONIGHT INTO MON MORNING. HEADLINES FOR REST OF ERN VA RIVERS
WILL LIKELY BE NEEDED FOR MON NIGHT INTO TUESDAY BUT WILL HOLD OFF
ON ISSUING THEM ATTM.
HIGH PRESSURE BEGINS TO SHIFT ACROSS THE OH VALLEY ON TUE...THEN
SHIFTS OVER NRN NEW ENGLAND TUE NIGHT THROUGH WED. THE PRESSURE
GRADIENT WILL REMAIN TIGHT OVER THE WATERS DURING THIS TIMEFRAME.
N WINDS WILL REMAIN ELEVATED IN LOW-END SCA WIND SPEEDS EARLY TUE
NIGHT...THEN START TO DIMINISH AFTER MIDNIGHT INTO WED. EXPECT
WINDS AFTER MIDNIGHT TO AOB 15 KT BAY/RIVERS/SOUND...AOB 20 KT
COASTAL WATERS. AS THE NRN NEW ENGLAND HIGH PRESSURE CENTER MOVES
ACROSS NRN NEW ENGLAND TO JUST OFF ITS COAST ON WED NIGHT INTO
THU...WINDS BECOME MORE NE-E/ONSHORE. SPEEDS WILL BEGIN TO SLACKEN
THROUGH WED AND DIMINISH FURTHER WED NIGHT INTO THU. WAVES ON CHES
BAY SHOULD START TO SUBSIDE BY WED AFTN...EXCEPT THE MOUTH OF THE
BAY WHERE ONSHORE WINDS WILL KEEP WAVES HIGHER THROUGH WED NIGHT.
SEAS SHOULD ALSO BE SLOW TO SUBSIDE BELOW 5 FT UNTIL SOMETIME THU
NIGHT/FRI. HIGH PRESSURE LINGERS OFF THE NRN NEW ENGLAND COAST
THROUGH FRI AND ONSHORE FLOW WILL PERSIST.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST TUESDAY FOR ANZ630>634-650-
652-654-656-658.
SMALL CRAFT ADVISORY UNTIL NOON EST MONDAY FOR ANZ638.
&&
$$
SYNOPSIS...LSA
NEAR TERM...MAM/LSA
SHORT TERM...LSA
LONG TERM...BMD
AVIATION...AJZ/DAP
MARINE...BMD
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
757 PM EST SUN NOV 17 2013
.SYNOPSIS...
A STRONG COLD FRONT WILL PASS THROUGH THE REGION LATE TONIGHT INTO
EARLY MONDAY MORNING. HIGH PRESSURE BEHIND THE COLD FRONT WILL
BUILD OVERHEAD LATE MONDAY THROUGH WEDNESDAY. THE HIGH WILL MOVE
OFF THE COAST THURSDAY AND A COLD FRONT MAY IMPACT THE AREA FRIDAY
AND SATURDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
00Z RADAR AND OBSERVATIONS INDICATE THE COLD FRONT HAS REACHED
WESTERN OHIO...AND CONTINUES TO PUSH RAPIDLY EASTWARD. SOME
AREAS OF LIGHT RAIN/SHOWERS HAVE MOVED INTO THE MOUNTAINS AND
PIEDMONT. THESE WILL IMPACT THE FORECAST AREA OVER THE NEXT
COUPLE OF HOURS. AFTER THE FIRST BATCH OF RAIN...A RESPITE IS
LIKELY FOR A WHILE THIS EVENING AS A DRY SLOT NOTED ON WATER VAPOR
IMAGERY MOVES INTO THE AREA.
BASED ON SHORT-TERM MODEL OUTPUT...THE COLD FRONT AND ITS
ASSOCIATED LINE OF SHOWERS IS EXPECTED TO REACH THE POTOMAC
HIGHLANDS AROUND 11PM - MIDNIGHT...THEN STEADILY CROSS THE CWA
OVERNIGHT...REACHING CHESAPEAKE BAY AROUND 5AM. THERE HAS BEEN
SOME RUN-TO-RUN INCONSISTENCY IN TERMS OF HOW WELL SHOWER ACTIVITY
WILL REMAIN ORGANIZED AS IT CROSSES THE CWA...ESPECIALLY EAST OF
THE BLUE RIDGE. HRRR HAD PREVIOUSLY HELD THE LINE OF HEAVY
SHOWERS TOGETHER...BUT ITS 22Z RUN JUST IN DETERIORATES THE LINE
SOUTH OF THE POTOMAC RIVER AS IT MOVES EWD. WHEREVER THE LINE
HOLDS TOGETHER...IT WILL HAVE THE POTENTIAL TO TAP INTO A VERY
STRONG LOW LEVEL JET STREAM...WHICH SHOULD REACH AROUND 55-65KTS
AT 850MB AS IT CROSSES THE AREA. WITH IT...GUSTY WINDS ARE
EXPECTED...WITH AN ISOLATED DAMAGING WIND THREAT. ISOLATED THUNDER
REMAINS POSSIBLE AS WELL.
A WIND ADVISORY IS IN EFFECT ACROSS MUCH OF THE POTOMAC HIGHLANDS
AND CENTRAL AND SOUTHERN SHENANDOAH VALLEYS FROM 9PM UNTIL 6 AM
MONDAY. THIS ADVISORY IS PRIMARILY FOR ELEVATIONS ABOVE 2500 FEET
ALONG THE ALLEGHENY FRONT AND BLUE RIDGE. WINDS LOOK LIKE THEY
WILL INCREASE QUICKLY THIS EVENING AND GUST BETWEEN 45 AND 55 MPH
AT THE RIDGE TOPS LATER THIS EVENING AND OVERNIGHT.
WENT WITH NAM MODEL FOR LOW TEMPERATURES TONIGHT...THE WARMER MODEL.
WE HAVE WARM AIR ADVECTION ON A PERSISTENT SOUTHERLY WIND PLUS
CLOUD COVER AHEAD OF THE COLD FRONT.
THE COLD FRONT WILL MOVE OFF TO OUR EAST MONDAY MORNING AND LOW
PRESSURE WILL TRACK ACROSS EASTERN CANADA MONDAY WHILE HIGH
PRESSURE BUILDS OVER THE CENTRAL CONUS. A WESTERLY FLOW BEHIND THE
FRONT WILL DRY THINGS OUT QUICKLY FOR MONDAY...ALLOWING FOR PLENTY
OF SUNSHINE. MONDAY WILL BE MILD DUE TO SUNSHINE ALONG WITH A
DOWNSLOPING FLOW...DESPITE COLD ADVECTION BEHIND THE FRONT. MAX
TEMPS WILL RANGE FROM THE UPPER 50S AND LOWER 60S IN THE
SHENANDOAH VALLEY TO THE UPPER 60S AND LOWER 70S NEAR WASHINGTON
AND BALTIMORE AS WELL AS SOUTHERN MARYLAND. CHILLIER CONDITIONS
ARE EXPECTED IN THE MOUNTAINS WITH TEMPS IN THE 40S. BREEZY
CONDITIONS ARE EXPECTED MONDAY DUE TO A DEEP MIXING LAYER.
WESTERLY WINDS WILL GUST FREQUENTLY AROUND 25 TO 30 MPH WITH GUSTS
AROUND 40 MPH IN THE MOUNTAINS.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
HIGH PRESSURE WILL BUILD OVERHEAD MONDAY NIGHT THROUGH WEDNESDAY.
DRY AND SEASONABLY CHILLY CONDITIONS ARE EXPECTED DURING THIS
TIME.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE WILL SLOWLY DRIFT OFF THE MID-ATLANTIC COAST WEDNESDAY
NIGHT INTO THURSDAY AS UPPER-LEVEL TROUGHING APPROACHES FROM THE
WEST. SURFACE REFLECTION IN THE FORM OF A COLD FRONT WILL APPROACH
THE AREA LATE THURSDAY INTO FRIDAY. SEASONABLE TEMPERATURES ARE
EXPECTED AHEAD OF THE FRONT THROUGH LATE IN THE WEEK. 17/12Z GFS
OPERATIONAL IN BETTER AGREEMENT WITH ITS 06Z ENSEMBLE MEAN AND
17/00Z ECMWF OPERATIONAL/ENSEMBLE MEAN WITH OVERALL PATTERN AND
TIMING OF THE FRONT...ALTHOUGH THE ECMWF TRIES TO DEVELOP A WAVE ON
THE FRONT AS IT CROSSES THE AREA. THE ECMWF IS ALSO A BIT COLDER
FRIDAY NIGHT. FOR NOW...FOLLOWED WPC GUIDANCE WHICH IS A 70/30 BLEND
OF THE 00Z ECMWF ENSEMBLE MEAN/06Z GFS ENSEMBLE MEAN.
THIS RESULTS IN A CHANCE OF PRECIPITATION BEGINNING AND ENDING FROM
WEST TO EAST EARLY FRIDAY MORNING THROUGH SATURDAY. ALTHOUGH BOTH
THE GFS AND TO A GREATER EXTENT THE ECMWF HINT AT COLDER AIR MOVING
IN BEFORE PRECIPITATION ENDS...KEPT ANY MENTION OF SNOW SHOWERS
MIXED WITH RAIN WELL NORTH AND WEST OF THE I-95 CORRIDOR GIVEN
CLIMATOLOGY AND INHERENT UNCERTAINTY/MODEL SPREAD AT THIS TIME RANGE.
A BLAST OF ARCTIC AIR FOLLOWS THE COLD FRONT LEADING TO BELOW NORMAL
TEMPERATURES AREA-WIDE NEXT WEEKEND.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
A COLD FRONT WILL MOVE THROUGH THE REGION OVERNIGHT INTO THE EARLY
MORNING HOURS MONDAY. A FEW PERIODS OF SHOWERS ARE EXPECTED...AND
MOST TERMINALS WILL SEE BRIEF HEAVY RAINFALL WITH POTENTIAL FOR
ISOLATED THUNDERSTORMS. AMENDMENTS LIKELY FOR TEMPO GROUPS FOR
THIS HEAVY RAINFALL ACTIVITY AND ASSOCIATED REDUCED CIGS/VSBYS AS
THE ACTIVITY APPROACHES AND TIMING BECOMES MORE CERTAIN. WINDS
WILL INCREASE AS THE EVENING PROGRESSES...WITH GUSTS AROUND 25KTS
AT DC METRO TERMINALS. HIGHER GUSTS POSSIBLE WITH ANY HEAVY
SHOWER/TSTM ACTIVITY. WINDS WILL SHIFT TO THE WEST AFTER THE FRONT
MOVES THROUGH LATE TONIGHT OR EARLY MONDAY.
VFR CONDITIONS ARE EXPECTED MONDAY THROUGH WEDNESDAY. WESTERLY WINDS
WILL GUST AROUND 25 KNOTS MONDAY BEFORE DIMINISHING TOWARD SUNSET.
NORTHWEST WINDS WILL GUST AROUND 15 TO 20 KNOTS TUESDAY. WINDS
TUESDAY NIGHT AND WEDNESDAY WILL BE LIGHT. HIGH PRESSURE WILL
REMAIN OVER THE TERMINALS LATE IN THE WEEK.
&&
.MARINE...
A SMALL CRAFT ADVISORY IS IN EFFECT TONIGHT FOR SOUTHERLY WINDS
AHEAD OF A COLD FRONT. THERE IS POTENTIAL FOR SPECIAL MARINE
WARNINGS OVERNIGHT AS SHOWERS WITH GUSTY WINDS MOVE THROUGH THE WATERS.
GUSTY WESTERLY WINDS ARE EXPECTED BEHIND A COLD FRONT MONDAY. A
SMALL CRAFT ADVISORY IS IN EFFECT FOR THE WATERS. THE SMALL CRAFT
ADVISORY CONTINUES MONDAY NIGHT FOR THE MARYLAND CHESAPEAKE BAY AND
TIDAL POTOMAC RIVER FROM INDIAN HEAD TO SMITH POINT.
A SMALL CRAFT ADVISORY MAY BE NEEDED FOR PORTIONS OF THE WATERS
TUESDAY AND TUESDAY NIGHT. HIGH PRESSURE WILL BUILD OVERHEAD
WEDNESDAY. A RELATIVELY BENIGN SURFACE PRESSURE GRADIENT WILL
LIKELY LEAD TO SUB-SCA CONDITIONS ON AREA WATERS WEDNESDAY NIGHT
THROUGH FRIDAY. A COLD FRONT MAY BRING SHOWERS TO THE WATERS
FRIDAY INTO SATURDAY...FOLLOWED BY INCREASINGLY GUSTY NW FLOW.
&&
.TIDES/COASTAL FLOODING...
ANOMALIES WILL CONTINUE TO INCREASE TONIGHT AS THE SOUTHERLY FLOW
INCREASES. HOWEVER...A COLD FRONT IS EXPECTED TO MOVE THROUGH
OVERNIGHT...WITH WINDS SHIFTING TO THE WEST BEFORE MORNING HIGH
TIDE MONDAY. THEREFORE...MINOR COASTAL FLOODING IS NOT EXPECTED
AS OF NOW. WILL CONTINUE TO MONITOR ANOMALIES BECAUSE CERTAINTY IS
LOW DUE TO THE GUSTY SOUTHERLY FLOW.
WEST WINDS WILL CONTINUE BEHIND THE COLD FRONT MONDAY AND
ANOMALIES WILL DECREASE. TIDAL BLOWOUT IS POSSIBLE LATE MONDAY AND
TUESDAY.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...WIND ADVISORY UNTIL 6 AM EST MONDAY FOR MDZ501.
VA...WIND ADVISORY UNTIL 6 AM EST MONDAY FOR VAZ025>027-029-030-
036>040-503-504.
WV...WIND ADVISORY UNTIL 6 AM EST MONDAY FOR WVZ055-501>503-505-506.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST TUESDAY FOR ANZ530>534-536-
537-539>541-543.
SMALL CRAFT ADVISORY UNTIL 6 PM EST MONDAY FOR ANZ535-538-542.
&&
$$
SYNOPSIS...BJL
NEAR TERM...KCS/KLW
SHORT TERM...BJL
LONG TERM...DFH
AVIATION...BJL/KCS/DFH
MARINE...BJL/KCS/DFH
TIDES/COASTAL FLOODING...KCS
AREA FORECAST DISCUSSION...UPDATED
NWS PITTSBURGH PA
1242 AM EST SAT NOV 16 2013
.SYNOPSIS...
A DRY DAY WITH WARMER TEMPERATURES. MORNING CLOUDS WILL GIVE WAY
TO SOME SUN IN THE AFTERNOON. A STRONG COLD FRONT WILL BRING WIND
AND RAIN TO THE AREA SUNDAY INTO EARLY MONDAY.
&&
.NEAR TERM /THROUGH TODAY/...
HAVE UPDATED OVERNIGHT POPS FOR SOUTHERN SHOWERS TO BE MORE IN
LINE WITH LATEST GUIDANCE. SHORTWAVE RESPONSIBLE FOR THE SHOWERS
IS QUICKLY MOVING INTO CENTRAL PA AND WILL REACH THE EASTERN PART
OF THE STATE AROUND 07Z. WITH SHORTWAVE GONE...SHOWERS EXIT THE
AREA FOLLOWED BY A BRIEF DECREASE IN CLOUD COVER. MID-LEVEL
MOISTURE TO THE SOUTHEAST...VISIBLE ON THE LATEST SAT PICS...WILL
ADVECT NORTHEASTWARD LATE TONIGHT. THIS WILL MEAN ANOTHER
INCREASE IN CLOUDS FROM SOUTHWEST TO NORTHEAST. WILL ADJUSTS
TEMPS TO LATEST GUIDANCE.
MID-LEVEL FLOW INCREASE THIS MORNING AND BACKS TO THE SOUTHWEST.
THIS WILL CONTINUE TO PULL THE MOISTURE NORTHWARD INTO THE UPPER
OHIO VALLEY...IN ADDITION TO WARMER AIR. STRONG WAA WILL BE IN FULL
FORCE BY THIS AFTERNOON AND MID-LEVEL MOISTURE LEVELS WILL
DECREASE. MODEL SOUNDINGS ARE DEPICTING THIS WELL SHOWING THE
OVERALL ATMOSPHERE DRYING OUT LATE THIS MORNING AND THROUGH THE
AFTERNOON. THE COMBINATION OF DECREASING CLOUD COVER AND WAA WILL
ALLOW FOR TEMPS TO GO 5 TO 10 DEGREES ABOVE NORMAL.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY/...
CLOUDS WILL QUICKLY INCREASE TONIGHT AS ANOTHER SHORTWAVE TROUGH
SWINGS THROUGH. THE FIRST WAVE WILL MOISTEN THINGS UP AND THE
SECOND WAVE...MOVING THROUGH AROUND DAWN...WILL PROVIDE SHOWERS
FOR THE REGION BY SUNDAY MORNING.
SUNDAY MORNINGS WAVE WILL EXIT BY EARLY AFTERNOON...WHICH WILL
ALLOW FOR A BRIEF BREAK IN THE WIDESPREAD RAINFALL. SURFACE WINDS
WILL BECOME GUSTY SUNDAY AFTERNOON AS THE SURFACE PRESSURE
GRADIENT TIGHTENS AND THE MIXING LAYER RISES...REACHING THE
STRONG WINDS ALOFT. ITS NOT OUT OF THE QUESTION THAT WINDS GUSTS
SUNDAY AFTERNOON COULD REACH CLOSE TO 40 MPH.
WIDESPREAD SHOWERS QUICKLY RE-ENTER THE AREA LATE SUNDAY AHEAD OF
THE MAIN COLD FRONT. IN ADDITION TO THE SHOWERS...GUSTY WINDS WILL
CONTINUE.
THE CONCERN SUNDAY EVENING/NIGHT WILL BE THE POSSIBILITY FOR
DAMAGING WINDS WITH THE FRONTAL PASSAGE. COLD FRONT WILL QUICKLY
MOVE THROUGH OHIO SUNDAY EVENING...REACHING WESTERN PA AROUND
MIDNIGHT. GUSTY WINDS WILL BE ONGOING AHEAD OF THE FRONT...BUT IT
APPEARS THAT THERE WILL BE AN INCREASED THREAT FOR DAMAGING WINDS
WITH THE PASSAGE OF THE FRONT. MODELS ARE SHOWING A THIN LINE OF
STRONG LOW LEVEL FORCING AND MOISTURE CONVERGENCE RIGHT AHEAD OF
THE SURFACE BOUNDARY. 0-1KM SHEAR VALUES WILL BE IN EXCESS OF
50KTS SUNDAY EVENING...PLENTY STRONG ENOUGH TO SUSTAIN ELEVATED
CONVECTION. MODEL SOUNDINGS ARE PORTRAYING A DEEP MIXING LAYER
DEVELOPING WITH STRONG LAPSE RATES MEANING THE VERY STRONG WINDS
ALOFT WILL HAVE NO ROADBLOCKS MIXING DOWN TO THE SURFACE.
CONVECTION WOULD NEED TO BE ELEVATED AS CONVECTIVE TEMPS AHEAD OF
THE FRONT ARE NEAR 70 DEGREES. THIS SCENARIO COULD PLAY OUT VERY
SIMILARLY TO THE WIND EVENT THAT OCCURRED A COUPLE OF WEEKS AGO
WHEN A LINE OF SHOWERS DEVELOPED WITH THE FRONT AND PROVIDED A
BRIEF PERIOD OF DAMAGING WINDS.
THE OTHER PART OF THE STORY THAT NEEDS TO BE CONSIDERED IS THE
STRONG PRESSURE RISES BEHIND THE FRONT AND SHOWERS. IT IS
POSSIBLE THAT THIS FEATURE COULD PROVIDE A SECOND ROUND OF STRONG
WIND GUSTS. THE MIXING LAYER WILL SHRINK...BUT WINDS ALOFT ARE
STILL PLENTY STRONG. IF THIS SECOND FEATURE COMES TO FRUITION...IT
TOO WOULD BE BRIEF.
MONDAY IS NOT SETTING UP AS TOO BAD OF A DAY. ATMOSPHERE IS DRY
BEHIND THE FRONT AND THE CAA WILL BE WEAK AND SLOW. TEMPS MONDAY
WILL BE MORE SEASONABLE.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A BRIEF PERIOD OF COLDER AIR AND THE POSSIBILITY FOR SNOW SHOWERS
MONDAY NIGHT. HIGH PRESSURE WILL RETURN DRY WEATHER AND PROVIDE
MODERATING TEMPERATURES FOR THE REMAINDER OF THE LONG TERM.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
WEAK TROUGH PASSING OVER THE AREA TONIGHT COULD RESULT IN PERIODS
OF LIGHT SHOWERS PRIMARILY SOUTH OF PITTSBURGH...BUT OPTED NOT
TO INCLUDE IN THE 00Z TAF PACKAGE FOR KMGW OR KZZV AS EXPECT
COVERAGE TO BE SCATTERED AND DURATION...IF ANY...BRIEF. VFR CONDS
EXPECTED OVERNIGHT...BUT LATEST RUC SOUNDINGS INDICATE THE
POTENTIAL FOR MVFR CLOUD COVERAGE BY MORNING BETWEEN 11Z AND 12Z.
VFR CONDTIONS THEN EXPECTED AREAWIDE BY LATE MORNING.
.OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
RSTRNS ALG WITH A PD OF LLWS AND GUSTY WNDS ARE EXPD WITH THE APCH
AND PASSAGE OF A STG CDFNT SUN AND SUN NGT. RSTRNS WL REMAIN PSBL
THRU ERLY TUE AS AN UPR TROF CROSSES THE GT LKS IN NW FLOW. BLDG
HIGH PRES RTNS VFR CONDS LT TUE.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
912 PM EST SUN NOV 17 2013
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 231 PM EST SUN NOV 17 2013
A STORMY EVENING WILL GIVE WAY TO SOME LEFTOVER SHOWERS OVERNIGHT
BUT STRONG WINDS WILL CONTINUE. THE DAMAGING WIND THREAT WILL
REMAIN BEYOND THE THUNDERSTORM THREAT THIS EVENING. COLDER AIR
MOVES IN TOMORROW WITH A FEW SNOW SHOWERS POSSIBLE.
&&
.UPDATE...
ISSUED AT 908 PM EST SUN NOV 17 2013
NO CHANGES TO THE HEADLINES. WE/VE SEEN MANY REPORTS OF WINDS
GUSTING OVER 60 MPH THIS EVENING. NUMEROUS POWER OUTAGES ARE
ONGOING. WINDS WILL SLOWLY DIMINISH OVERNIGHT. RADAR SHOWS THE
BACK EDGE OF THE RAIN SHIELD GETTING CLOSER TO THE LAKE SHORE.
PCPN WILL TAPER OFF BY LATE EVENING.
UPDATE ISSUED AT 621 PM EST SUN NOV 17 2013
THE THREAT FOR SEVERE STORMS HAS ENDED HOWEVER NOW WE HAVE THE
WRAP AROUND HIGH WINDS AND SHOWERS SPREADING INTO THE AREA. MODELS
SHOW A CORE OF 55 TO 60 KNOT WINDS BETWEEN 1000 AND 3000 FEET
BETWEEN NOW AND ABOUT 10 PM. WINDS IN THE CHICAGO AREA WERE
GUSTING TO BETWEEN 45 AND 55 MPH OVER THE PAST HOUR OR SO AND
THESE STRONG WINDS WILL SPREAD ACROSS THE AREA THIS EVENING. ALSO
EXPECT SHOWERS AS THE COLD AIR SPREADS ACROSS AREA. THE SHOWERS
SHOULD SHOULD DIMINISH LATER THIS EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 231 PM EST SUN NOV 17 2013
NO MAJOR CHANGES TO GOING FORECAST. MAINTAINED HIGH WIND GUSTS
INTO THE OVERNIGHT HOURS WITH A GRADUAL DECREASE EXPECTED BY MID
TO LATE MORNING ON MONDAY. THE GREATEST IMPACT WEATHER WILL
CONTINUE TO BE THIS EVENING WITH THE SEVERE WEATHER THREAT
CONTINUING AT LEAST THROUGH EARLY EVENING (SEE MESOSCALE
DISCUSSION). SYNOPTIC WINDS CONTINUE TO RAMP UP THIS EVENING AND
TONIGHT WITH WIND GUSTS REACHING THE 50-60 MPH RANGE FOR ALL LAND
AREAS. THESE WINDS COULD BE DAMAGING AT TIMES AND POWER OUTAGES
WILL LIKELY OCCUR ACROSS PORTIONS OF SW LOWER MICHIGAN. SOME LAKE
EFFECT RAIN AND SNOW SHOWERS ARE POSSIBLE MONDAY BUT NO
SIGNIFICANT ACCUMULATIONS AND IMPACTS ARE EXPECTED FROM THIS ACTIVITY.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 231 PM EST SUN NOV 17 2013
NO CHANGES TO LONG TERM GIVEN THE SEVERE WEATHER THREAT THIS AFTERNOON.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 621 PM EST SUN NOV 17 2013
VERY STRONG WINDS WILL SPREAD ACROSS THE TAF SITES THIS EVENING AS
THE COLD AIR SPREADS INTO THE AREA BEHIND THE COLD FRONT. THE CORE
OF STRONGEST WINDS IS BETWEEN 00Z AND 03Z WINDS WILL SLOWLY
DIMINISH AFTER THAT.
BOTH THE NAM AND RAP MODELS SUGGEST SHOWERS WITH MVFR CIGS AS THE
CORE OF STRONG WINDS MOVES THROUGH THE AREA... BUT THEN THE CLOUDS
MAY BREAK UP SOME AFTER 06Z.
AS THE CORE OF COLDEST AIR MOVES IN AROUND 12Z CIGS SHOULD BECOME
MVFR ONCE AGAIN AND THIS TIME THERE COULD BE A FEW SNOW SHOWERS
BUT DUE TO THE LIMITED INVERSION HEIGHTS... VISIBILITIES SHOULD
MOSTLY BE MVFR OR BETTER AND THAT WILL BE LIMITED TO THE I-96
TAFS. I PUT VCSH FOR NOW SINCE I DO NOT EXPECT THE SNOW SHOWERS TO
BE FREQUENT.
&&
.MARINE...
ISSUED AT 231 PM EST SUN NOV 17 2013
STORM WARNING CONTINUES WITH THE WORST CONDITIONS COMING TONIGHT.
PEAK WAVE HEIGHTS OF 10-15 FEET ARE POSSIBLE ACROSS THE NEARSHORE
ZONES TONIGHT. A FEW WIND GUSTS TO 55 KTS ARE NOT IMPOSSIBLE. A
GRADUAL DECREASE IN WIND AND WAVE ACTIVITY IS EXPECTED MONDAY
ALTHOUGH GALES WILL STILL BE POSSIBLE.
&&
.HYDROLOGY...
ISSUED AT 231 PM EST SUN NOV 17 2013
STORM TOTAL RAINFALL WITH THIS EVENT WILL BE RANGING FROM 0.50
INCH AROUND JACKSON AND OUR SE FORECAST AREA TO AN INCH OR MORE
FROM GRAND RAPIDS TO THE NW. NOT EXPECTING THIS TO BE A FLASH
FLOODING OR EVEN AREAL FLOODING SITUATION GIVEN THE VERY FAST
NATURE OF THESE STORMS. LOCAL PONDING OF ROADS IS CERTAINLY
POSSIBLE GIVEN THE LEAVES THAT COULD BE CLOGGING DRAINS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...HIGH WIND WARNING UNTIL 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.
&&
$$
UPDATE...93
SYNOPSIS...HOVING
SHORT TERM...HOVING
LONG TERM...HOVING
AVIATION...WDM
HYDROLOGY...HOVING
MARINE...HOVING
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
622 PM EST SUN NOV 17 2013
LATEST UPDATE...
UPDATE/AVIATION
.SYNOPSIS...
ISSUED AT 231 PM EST SUN NOV 17 2013
A STORMY EVENING WILL GIVE WAY TO SOME LEFTOVER SHOWERS OVERNIGHT
BUT STRONG WINDS WILL CONTINUE. THE DAMAGING WIND THREAT WILL
REMAIN BEYOND THE THUNDERSTORM THREAT THIS EVENING. COLDER AIR
MOVES IN TOMORROW WITH A FEW SNOW SHOWERS POSSIBLE.
&&
.UPDATE...
ISSUED AT 621 PM EST SUN NOV 17 2013
THE THREAT FOR SEVERE STORMS HAS ENDED HOWEVER NOW WE HAVE THE
WRAP AROUND HIGH WINDS AND SHOWERS SPREADING INTO THE AREA. MODELS
SHOW A CORE OF 55 TO 60 KNOT WINDS BETWEEN 1000 AND 3000 FEET
BETWEEN NOW AND ABOUT 10 PM. WINDS IN THE CHICAGO AREA WERE
GUSTING TO BETWEEN 45 AND 55 MPH OVER THE PAST HOUR OR SO AND
THESE STRONG WINDS WILL SPREAD ACROSS THE AREA THIS EVENING. ALSO
EXPECT SHOWERS AS THE COLD AIR SPREADS ACROSS AREA. THE SHOWERS
SHOULD SHOULD DIMINISH LATER THIS EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 231 PM EST SUN NOV 17 2013
NO MAJOR CHANGES TO GOING FORECAST. MAINTAINED HIGH WIND GUSTS
INTO THE OVERNIGHT HOURS WITH A GRADUAL DECREASE EXPECTED BY MID
TO LATE MORNING ON MONDAY. THE GREATEST IMPACT WEATHER WILL
CONTINUE TO BE THIS EVENING WITH THE SEVERE WEATHER THREAT
CONTINUING AT LEAST THROUGH EARLY EVENING (SEE MESOSCALE
DISCUSSION). SYNOPTIC WINDS CONTINUE TO RAMP UP THIS EVENING AND
TONIGHT WITH WIND GUSTS REACHING THE 50-60 MPH RANGE FOR ALL LAND
AREAS. THESE WINDS COULD BE DAMAGING AT TIMES AND POWER OUTAGES
WILL LIKELY OCCUR ACROSS PORTIONS OF SW LOWER MICHIGAN. SOME LAKE
EFFECT RAIN AND SNOW SHOWERS ARE POSSIBLE MONDAY BUT NO
SIGNIFICANT ACCUMULATIONS AND IMPACTS ARE EXPECTED FROM THIS ACTIVITY.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 231 PM EST SUN NOV 17 2013
NO CHANGES TO LONG TERM GIVEN THE SEVERE WEATHER THREAT THIS AFTERNOON.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 621 PM EST SUN NOV 17 2013
VERY STRONG WINDS WILL SPREAD ACROSS THE TAF SITES THIS EVENING AS
THE COLD AIR SPREADS INTO THE AREA BEHIND THE COLD FRONT. THE CORE
OF STRONGEST WINDS IS BETWEEN 00Z AND 03Z WINDS WILL SLOWLY
DIMINISH AFTER THAT.
BOTH THE NAM AND RAP MODELS SUGGEST SHOWERS WITH MVFR CIGS AS THE
CORE OF STRONG WINDS MOVES THROUGH THE AREA... BUT THEN THE CLOUDS
MAY BREAK UP SOME AFTER 06Z.
AS THE CORE OF COLDEST AIR MOVES IN AROUND 12Z CIGS SHOULD BECOME
MVFR ONCE AGAIN AND THIS TIME THERE COULD BE A FEW SNOW SHOWERS
BUT DUE TO THE LIMITED INVERSION HEIGHTS... VISIBILITIES SHOULD
MOSTLY BE MVFR OR BETTER AND THAT WILL BE LIMITED TO THE I-96
TAFS. I PUT VCSH FOR NOW SINCE I DO NOT EXPECT THE SNOW SHOWERS TO
BE FREQUENT.
&&
.MARINE...
ISSUED AT 231 PM EST SUN NOV 17 2013
STORM WARNING CONTINUES WITH THE WORST CONDITIONS COMING TONIGHT.
PEAK WAVE HEIGHTS OF 10-15 FEET ARE POSSIBLE ACROSS THE NEARSHORE
ZONES TONIGHT. A FEW WIND GUSTS TO 55 KTS ARE NOT IMPOSSIBLE. A
GRADUAL DECREASE IN WIND AND WAVE ACTIVITY IS EXPECTED MONDAY
ALTHOUGH GALES WILL STILL BE POSSIBLE.
&&
.HYDROLOGY...
ISSUED AT 231 PM EST SUN NOV 17 2013
STORM TOTAL RAINFALL WITH THIS EVENT WILL BE RANGING FROM 0.50
INCH AROUND JACKSON AND OUR SE FORECAST AREA TO AN INCH OR MORE
FROM GRAND RAPIDS TO THE NW. NOT EXPECTING THIS TO BE A FLASH
FLOODING OR EVEN AREAL FLOODING SITUATION GIVEN THE VERY FAST
NATURE OF THESE STORMS. LOCAL PONDING OF ROADS IS CERTAINLY
POSSIBLE GIVEN THE LEAVES THAT COULD BE CLOGGING DRAINS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...HIGH WIND WARNING UNTIL 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.
&&
$$
UPDATE...WDM
SYNOPSIS...HOVING
SHORT TERM...HOVING
LONG TERM...HOVING
AVIATION...WDM
HYDROLOGY...HOVING
MARINE...HOVING
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
341 PM EST SAT NOV 16 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 521 AM EST SAT NOV 16 2013
SOUTHWESTERLY FLOW IS BEGINNING TO INCREASE OVER THE CWA AS THE
UPPER TROUGH AMPLIFIES DUE TO A STRONG SHORTWAVE MOVING SOUTHEAST
THROUGH THE PACIFIC NORTHWEST. THIS SHORTWAVE WILL BE THE MAJOR
PLAYER TO OUR WEATHER FOR THE SECOND HALF OF THE WEEKEND.
FOR THE SHORT TERM...THE SOUTHWESTERLY FLOW ALOFT WILL ALLOW A
SHORTWAVE CURRENTLY LOCATED NEAR THE FOUR CORNERS REGION TO MOVE
NORTHEAST ACROSS THE UPPER GREAT LAKES LATE THIS AFTERNOON AND
EVENING. MOISTURE STREAMING NORTHEAST ON WV IMAGERY IS LEADING TO
SOME HIGH CLOUDS OVER MUCH OF UPPER MICHIGAN. IN THE LOWER
LEVELS...INITIAL RAP SOUNDINGS SHOWING PLENTY OF DRY AIR BELOW THE
HIGH CLOUDS BUT THERE WAS ENOUGH RADIATIONAL COOLING EARLIER
THIS EVENING TO PRODUCE SOME PATCHY FOG OVER CENTRAL/EASTERN
UPPER MICHIGAN. THE DRIER LOW LEVELS WILL LIKELY BE SHORT LIVED
AS 3-5KFT CEILINGS COVER MUCH OF CENTRAL/NORTHERN WISCONSIN AND WILL
BE MOVING INTO THE AREA OVER THE NEXT COUPLE OF HOURS. IN ADDITION
TO THOSE CLOUDS...MODELS ARE SHOWING THE DEVELOPING 1KFT CEILINGS
IN NORTHERN ILLINOIS TO QUICKLY LIFT NORTH AND EXPAND THIS MORNING
AND EARLY AFTERNOON...COVERING MUCH OF UPPER MICHIGAN.
THE SHORTWAVE WILL BE NEARING THE REGION THIS AFTERNOON AND THERE
ARE SEVERAL FEATURES SUPPORTING A BROAD AREA OF RAIN MOVING THROUGH
THE AREA LATE THIS AFTERNOON AND EVENING. FIRST...EXPECT THERE TO
BE A WEAK COUPLED JET STRUCTURE OVER THE AREA THIS EVENING. BROAD
MID LEVEL WARM AIR ADVECTION AND MOISTURE TRANSPORT WILL ACCOMPANY
THIS SHORTWAVE...WITH THE EASTERN CWA SEEING THE BEST OF BOTH
FEATURES. AT THE SURFACE...THE BROAD LOW DEVELOPING OVER THE
CENTRAL/NORTHERN PLAINS WILL SLIDE A TROUGH THROUGH MINNESOTA TODAY
AND OVER WESTERN LAKE SUPERIOR TONIGHT. HAVE HIGH CONFIDENCE IN THE
FORECAST FOR THIS AFTERNOON/EVENING BASED OFF GREAT MODEL
CONSISTENCY. SINCE THE BEST FORCING IS OVER THE SOUTHEAST
HALF...WILL HAVE THE HIGHEST POPS/QPF IN THAT AREA BUT THERE WILL BE
A PERIOD OF DEFINITE POPS OVER THE ENTIRE AREA. AS FOR QPF...EXPECT
VALUES TO RANGE FROM 0.2 OVER THE WEST TO 0.75IN OVER THE
EAST...WITH SOME HIGHER AMOUNTS IF THERE ARE SOME EMBEDDED
THUNDERSTORMS.
AS FOR THUNDER...THERE IS A POCKET OF 50-125J/KG OF MUCAPE AND
SHOWALTER VALUES SLIGHTLY BELOW 0 OVER THE EASTERN 2/3RDS OF THE CWA
LATE THIS AFTERNOON INTO THE EVENING HOURS. BOTH 00Z NAM AND 21Z
SREF PROBABILITIES INDICATE THE POTENTIAL FOR A RUMBLE OF THUNDER OR
TWO OVER THE SOUTHEAST PART OF THE CWA...WHICH CORRELATES WELL WITH
POCKET OF STEEPER 850-500MB LAPSE RATES MOVING THROUGH AND BEST
FORCING. PREVIOUS SHIFT HAD A SLIGHT CHANCE MENTIONED (WHICH SEEMS
REASONABLE) AND ONLY MADE MINOR TWEAKS.
ALL OF THE FORCING FEATURES WILL SHIFT NORTHEAST AROUND OR SHORTLY
AFTER MIDNIGHT (AND MID LEVEL DRYING OCCURS)...SO HAVE A DIMINISHING
TREND TO THE POPS FROM SOUTHWEST TO NORTHEAST. WITH THE DEEP
MOISTURE DEPARTING...DID TRANSITION THE PRECIP WORDING FROM RAIN TO
DRIZZLE OVERNIGHT (MAINLY OVER THE EASTERN AREAS). MODELS MATCH UP
WITH THAT IDEA (BLOTCHY LOOK TO QPF IN THE HIGHER RESOLUTION RUNS).
DID CONTINUE TO MENTION SOME FOG WITH THE RAIN THIS
EVENING...ALTHOUGH THE WIND MIGHT HELP KEEP IT MORE OF A
STRATUS WITH ONLY A SLIGHT LOWERING OF VISIBILITIES EXCEPT OVER THE
HIGHER TERRAIN. THUS...HAVE KEPT MOST OF THE AREA UNDER PATCHY
WORDING...ALTHOUGH DID IT DIMINISH OVER THE WEST OVERNIGHT AS
LOWER LEVEL AIR SLIDES IN.
FINALLY...WILL SEE INCREASING SOUTHERLY WINDS TODAY WITH A
TIGHTENING PRESSURE GRADIENT BETWEEN THE HIGH OFF THE EAST COAST AND
TROUGH MOVING EAST THROUGH MINNESOTA. STRONGEST WINDS WILL BE OVER
THE EASTERN CWA...WHERE THE LOW LEVEL JET WILL BE LOCATED. WITH THE
INCREASING LOW LEVEL MOISTURE AND EXPECTED CLOUD COVER...THINK THAT
WILL LIMIT MIXING AND KEEP WINDS IN CHECK (OCCASIONAL GUSTS IN THE
20-30MPH RANGE SEEN ON BUFKIT MOMENTUM TRANSFER). ABOVE NORMAL
TEMPERATURES WILL CONTINUE TODAY AND TONIGHT AS WARM AIR SLIDES
NORTH OVER THE AREA. THIS WARM AIR WILL REALLY SURGE IN
TONIGHT...WHICH COULD CAUSE MOST LOWS TO OCCUR EARLY THIS EVENING
AND THEN RISING OVERNIGHT INTO THE UPPER 40S AND AROUND 50.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 521 AM EST SAT NOV 16 2013
LONG TERM WILL START WITH A STRONG STORM SYSTEM LIFTING THRU THE
UPPER GREAT LAKES...BRINGING RAIN AND THEN A TRANSITION TO STRONG
WINDS...SNOW SHOWERS AND SEASONABLY COLD AIR. IT STILL LOOKS LIKE A
TREND TO LESS AMPLIFIED FLOW TOWARD THE MIDDLE OF NEXT WEEK. THAT
MAY ONLY BE SHORT-LIVED AS MEDIUM RANGE GUIDANCE IS NOW INDICATING A
SHARPER PROGRESSIVE TROF MOVING ACROSS THE NRN CONUS MID/LATE WEEK
RATHER THAN TROF REMAINING MORE CONFINED TO CANADA THAT HAD BEEN
INDICATED IN RECENT DAYS MODEL RUNS. END RESULT IS MODERATING TEMPS
AND A DRIER PATTERN HEADING INTO MID WEEK AND THEN A TURN TO COLDER
WEATHER LATE WEEK...ACCOMPANIED BY SOME -SHSN AND FOLLOWED BY
PROBABLY LIGHT LES OFF LAKE SUPERIOR.
BEGINNING SUN...ATTENTION WILL BE ON A STRONG SHORTWAVE SWINGING OUT
ACROSS THE CNTRL PLAINS. WAVE WILL GO NEGATIVE TILT AND RAPIDLY
DEEPEN AS IT PASSES ACROSS THE GREAT LAKES SUN NIGHT. 12HR 500MB
HEIGHT FALLS ARE STILL FCST TO MAX OUT AROUND AN IMPRESSIVE 280M TO
THE NE AND E OF GEORGIAN BAY. MAJORITY OF GUIDANCE STILL INDICATES
DEEPENING SFC LOW LIFTING NE THRU WI AND SE LAKE SUPERIOR...WHICH
WAS THE PREFERRED TRACK 24HRS AGO. THE GFS IS STILL THE OUTLIER WITH
A FARTHER E TRACK...PASSING ACROSS THE STRAITS AND DRUMMOND ISLAND.
IF ANYTHING...THE GFS HAS BEEN TRENDING VERY SLIGHTLY FARTHER S AND
E WITH THE TRACK IN RECENT RUNS. WILL CONTINUE TO USE THE MORE
CLIMATOLOGICALLY FAVORED SFC LOW TRACK ACROSS FAR SE LAKE
SUPERIOR...REPRESENTED BY THE ECMWF/UKMET/GEM AND 4KM NAM WINDOW.
INCREASING HEIGHT FALLS AND STRONG UPPER DIFFLUENCE WITH LEFT EXIT
OF 130KT UPPER JET NOSING INTO THE GREAT LAKES WILL SUPPORT AN AREA
OF SHRA SPREADING N INTO UPPER MI SUN AFTN...WITH THE HEAVIEST PCPN
PROBABLY SLIDING THRU CNTRL/ERN UPPER MI LATE AFTN/EVENING WHERE
LOW/MID LEVEL FRONTOGENESIS AND ISENTROPIC ASCENT ARE STRONGEST.
WITH SHOWALTER INDEX FALLING TO SLIGHTLY NEGATIVE...WILL CONTINUE A
MENTION OF THUNDER OVER ROUGHLY THE E HALF OF THE FCST AREA...
GENERALLY ALONG AND E OF EXPECTED SFC LOW TRACK. COLDER AIR WRAPPING
IN BEHIND THE SYSTEM WILL CHANGE RAIN TO SNOW RATHER QUICKLY FROM W
TO E DURING SUN NIGHT PER CONSENSUS OF MODEL THERMAL
FIELDS/SOUNDINGS. POTENTIAL FOR HVY SNOW OR EVEN MDT SNOW IS NOTABLY
DIMINISHED FROM WHAT SOME MODEL RUNS SUGGESTED IN RECENT DAYS.
BIGGEST PROBLEM IS TIMING OF HOW FAST DEFORMATION PCPN SHIELD
DEVELOPS/EXPANDS/ORGANIZES ON NW/W SIDE OF SYSTEM. WITH THE FAST
SPEED OF SHORTWAVE THRU THE WRN GREAT LAKES AND WITH SFC/MID LEVEL
SYSTEM NOT BECOMING WELL DEVELOPED UNTIL NE OF THE AREA...IT DOESN`T
APPEAR THE SYNOPTIC SNOW SHIELD WILL BECOME REALLY ORGANIZED UNTIL
IT MOVES INTO NRN ONTARIO TO THE N AND NE OF LAKE SUPERIOR. IT WILL
PROBABLY TURN INTO A FAIRLY SUBSTANTIAL SNOW STORM FOR AREAS BTWN
LAKE SUPERIOR AND JAMES BAY...ESPECIALLY TOWARD JAMES BAY.
AS IT APPEARS NOW...THE STEADIER/HEAVIER PCPN IN THE EVENING OVER
THE W WILL PROBABLY FALL MOSTLY AS RAIN. BY THE TIME COLUMN COOLS
SUFFICIENTLY FOR A CHANGEOVER TO SNOW...THE SYNOPTIC PCPN WILL BE
PULLING OUT. STILL...WITH CYCLONIC FLOW/850MB TEMPS FALLING TO
AROUND -9C BY 12Z MON AND DEEPER MOISTURE HANGING AROUND...EXPECT
LAKE ENHANCED SNOW TO DEVELOP OFF WRN LAKE SUPERIOR OVERNIGHT. MIGHT
SEE A FEW INCHES OF SNOW IN THE HIGHER TERRAIN OF THE W BY SUNRISE
MON...BUT WITH DENDRITIC SNOW GROWTH TEMPS ABOVE THE UPWARD MOTION
ZONE AND POTENTIALLY EVEN ABOVE THE MOIST LAYER...IT MAY BE TOUGH TO
GET A FEW INCHES OF SNOW. STRONG BOUNDARY LAYER WINDS SHOULD TEND TO
SPREAD THE LAKE ENHANCED SNOW A BIT FARTHER INLAND THAN IS USUALLY
THE CASE. HURON MTNS MAY BE AN AREA TO SEE MOST PERISTENT SNOWFALL.
LATE CHANGEOVER TO SNOW OVER THE E WILL FURTHER LIMIT SNOW
ACCUMULATIONS IN THAT AREA SUN NIGHT. NO HEADLINES PERTAINING TO
SNOW ARE WARRANTED AT THIS TIME.
WINDS WILL BE A BIG STORY WITH THE SYSTEM. IN THE WAKE OF THE
DEEPENING SFC LOW...MODELS INDICATE NW WINDS OF 45-55KT AT 850MB
DURING THE PERIOD OF CAA. 4KM HIGH RES NAM SHOWS WIND GUST POTENTIAL
TO A LITTLE OVER 40KT OVER THE KEWEENAW AND TO A LITTLE OVER 50KT
ALONG THE LAKESHORE E OF MARQUETTE. ISALLOBARIC WIND COMPONENT WILL
ADD SOME ENHANCEMENT AS PRES RISES STRENGTHEN OVER THE AREA IN THE
WAKE OF THE DEEPENING LOW. IF ADVY HEADLINES END UP NOT BEING NEEDED
FOR SNOWFALL...WIND HEADLINES WILL BE NEEDED. ON LAKE SUPERIOR...
HIGH GALES ARE LIKELY ON THE E HALF OF LAKE SUPERIOR WITH DECENT
POTENTIAL FOR A PERIOD OF STORM FORCE WINDS LATE OVERNIGHT SUN NIGHT
INTO MON MORNING.
TRANSITION TO PURE LES WILL OCCUR MON/MON NIGHT UNDER NW FLOW AS
850MB TEMPS FALL TO -10/-11C. LINGERING LIGHT LES WILL WIND DOWN/END
OVER WRN UPPER MI MON NIGHT AND OVER NCNTRL UPPER MI TUE MORNING AS
AS FLOW BACKS AND WAA GETS UNDERWAY. WITH SFC HIGH PRES RIDGE
REACHING WRN UPPER MI LATE MON NIGHT...TEMPS COULD PLUMMET IF CLOUDS
CLEAR OUT. NONE OF THE GUIDANCE IS ESPECIALLY COLD. LOWEST GUIDANCE
GENERALLY SUGGEST MINS IN THE UPPER TEENS...AND FCST WILL REFLECT
THESE COLDER NUMBERS.
WAA WED MIGHT YIELD SOME LIGHT PCPN AT THAT TIME. THEN...STRONG
SHORTWAVE MOVING ACROSS SRN CANADA WILL SWEEP ASSOCIATED COLD FRONT
ACROSS THE AREA WED NIGHT...ACCOMPANIED BY SOME -RA/-SN. LES MAY GET
UNDERWAY THU...BUT MODELS HAVE NOT BEEN VERY CONSISTENT ON THE
INTENSITY OF THE COLD FOLLOWING THE FRONT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 121 PM EST SAT NOV 16 2013
ON FAVORABLE S WINDS WITH APPROACHING LOW LEVEL MOISTURE...CEILINGS
AT SAW QUICKLY FELL INTO THE IFR CATEGORY ...WHERE THEY WILL PRETTY
MUCH STAY /IFR TO LIFR/ THROUGH SUNDAY MORNING. AT THE OTHER
SITES...THE LOWER CLOUDS HAVE BEEN SLOWER TO ARRIVE...WITH IFR OR
MVFR CEILINGS EXPECTED TO SET IN THROUGH 09Z SUNDAY. SAW IS CLOSE TO
LLWS CRITERIA FROM 23Z SATURDAY THROUGH 06Z SUNDAY. HOWEVER...WITH
SFC WINDS STAYING UP WITH GUSTS ON THE ORDER OF 20-25KTS...WILL
EXCLUDE THE MENTION OF LLWS AT THIS TIME. RAIN WILL BE THE MAIN
WEATHER TYPE. LOOKING FARTHER AHEAD...EXPECT STRONG NW WINDS TO PUSH
IN BEHIND THE EXITING SFC LOW AFTER 00Z MONDAY. THE STRONGEST WINDS
WITH GUSTS NEAR 30KTS AT CMX AND TO A LESS EXTENT SAW...CONTINUING
THROUGH MID MORNING MONDAY.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 340 PM EST SAT NOV 16 2013
GALE AND STORM FORCE WIND WATCHES REMAIN IN PLACE FOR MUCH OF LAKE
SUPERIOR FOR LATE SUNDAY EVENING THROUGH MONDAY MORNING.
LOW PRESSURE OVER SOUTHERN MINNESOTA WILL SWING ACROSS
WESTERN LAKE SUPERIOR SUNDAY MORNING...WHILE AN ADDITIONAL LOW TO
THE SOUTH NEARS FROM THE SOUTHWEST. EXPECT THE LOWS TO COMBINE AND
DEEPEN SIGNIFICANTLY ACROSS FAR EASTERN LAKE SUPERIOR BY LATE SUNDAY
AFTERNOON...BEFORE EXITING NORTHEASTWARD TO JUST EAST OF JAMES BAY
MONDAY AFTERNOON. NW GALE TO STORM FORCE REMAIN POSSIBLE OVER MUCH
OF LAKE SUPERIOR LATE SUNDAY EVENING THROUGH MONDAY MORNING...WITH
GALES EXTENDING THROUGH EARLY MONDAY EVENING ACROSS THE E HALF OF
LAKE SUPERIOR.
HIGH PRESSURE STRETCHING FROM CENTRAL CANADA THROUGH THE SOUTHERN
PLAINS MONDAY WILL SLIDE ACROSS THE UPPER GREAT LAKES MONDAY NIGHT
AND TUESDAY. BEHIND THE EXITING HIGH...LOW PRESSURE ALONG THE
WESTERN U.S. AND CANADIAN BORDER ON TUESDAY WILL CROSS LAKE WINNIPEG
TUESDAY NIGHT INCHES...AND EXIT NORTHEAST ACROSS HUDSON BAY
WEDNESDAY INTO WEDNESDAY NIGHT WHILE DRAGGING A TROUGH ACROSS LAKE
SUPERIOR. EXPECT STRONG HIGH PRESSURE ACROSS THE PLAINS STATES
THURSDAY MORNING TO BUILD ACROSS THE UPPER GREAT LAKES BY THURSDAY
NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
HIGH WIND WATCH FROM SUNDAY EVENING THROUGH MONDAY AFTERNOON FOR
MIZ001-006-007.
LAKE SUPERIOR...
STORM WATCH FROM SUNDAY EVENING THROUGH MONDAY AFTERNOON FOR
LSZ244-245-248>251-264>267.
GALE WATCH FROM SUNDAY EVENING THROUGH MONDAY AFTERNOON FOR
LSZ241>243-263.
LAKE MICHIGAN...
GALE WATCH FROM SUNDAY EVENING THROUGH MONDAY MORNING FOR LMZ221-
248-250.
&&
$$
SHORT TERM...SRF
LONG TERM...ROLFSON
AVIATION...KF
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
123 PM EST SAT NOV 16 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 521 AM EST SAT NOV 16 2013
SOUTHWESTERLY FLOW IS BEGINNING TO INCREASE OVER THE CWA AS THE
UPPER TROUGH AMPLIFIES DUE TO A STRONG SHORTWAVE MOVING SOUTHEAST
THROUGH THE PACIFIC NORTHWEST. THIS SHORTWAVE WILL BE THE MAJOR
PLAYER TO OUR WEATHER FOR THE SECOND HALF OF THE WEEKEND.
FOR THE SHORT TERM...THE SOUTHWESTERLY FLOW ALOFT WILL ALLOW A
SHORTWAVE CURRENTLY LOCATED NEAR THE FOUR CORNERS REGION TO MOVE
NORTHEAST ACROSS THE UPPER GREAT LAKES LATE THIS AFTERNOON AND
EVENING. MOISTURE STREAMING NORTHEAST ON WV IMAGERY IS LEADING TO
SOME HIGH CLOUDS OVER MUCH OF UPPER MICHIGAN. IN THE LOWER
LEVELS...INITIAL RAP SOUNDINGS SHOWING PLENTY OF DRY AIR BELOW THE
HIGH CLOUDS BUT THERE WAS ENOUGH RADIATIONAL COOLING EARLIER
THIS EVENING TO PRODUCE SOME PATCHY FOG OVER CENTRAL/EASTERN
UPPER MICHIGAN. THE DRIER LOW LEVELS WILL LIKELY BE SHORT LIVED
AS 3-5KFT CEILINGS COVER MUCH OF CENTRAL/NORTHERN WISCONSIN AND WILL
BE MOVING INTO THE AREA OVER THE NEXT COUPLE OF HOURS. IN ADDITION
TO THOSE CLOUDS...MODELS ARE SHOWING THE DEVELOPING 1KFT CEILINGS
IN NORTHERN ILLINOIS TO QUICKLY LIFT NORTH AND EXPAND THIS MORNING
AND EARLY AFTERNOON...COVERING MUCH OF UPPER MICHIGAN.
THE SHORTWAVE WILL BE NEARING THE REGION THIS AFTERNOON AND THERE
ARE SEVERAL FEATURES SUPPORTING A BROAD AREA OF RAIN MOVING THROUGH
THE AREA LATE THIS AFTERNOON AND EVENING. FIRST...EXPECT THERE TO
BE A WEAK COUPLED JET STRUCTURE OVER THE AREA THIS EVENING. BROAD
MID LEVEL WARM AIR ADVECTION AND MOISTURE TRANSPORT WILL ACCOMPANY
THIS SHORTWAVE...WITH THE EASTERN CWA SEEING THE BEST OF BOTH
FEATURES. AT THE SURFACE...THE BROAD LOW DEVELOPING OVER THE
CENTRAL/NORTHERN PLAINS WILL SLIDE A TROUGH THROUGH MINNESOTA TODAY
AND OVER WESTERN LAKE SUPERIOR TONIGHT. HAVE HIGH CONFIDENCE IN THE
FORECAST FOR THIS AFTERNOON/EVENING BASED OFF GREAT MODEL
CONSISTENCY. SINCE THE BEST FORCING IS OVER THE SOUTHEAST
HALF...WILL HAVE THE HIGHEST POPS/QPF IN THAT AREA BUT THERE WILL BE
A PERIOD OF DEFINITE POPS OVER THE ENTIRE AREA. AS FOR QPF...EXPECT
VALUES TO RANGE FROM 0.2 OVER THE WEST TO 0.75IN OVER THE
EAST...WITH SOME HIGHER AMOUNTS IF THERE ARE SOME EMBEDDED
THUNDERSTORMS.
AS FOR THUNDER...THERE IS A POCKET OF 50-125J/KG OF MUCAPE AND
SHOWALTER VALUES SLIGHTLY BELOW 0 OVER THE EASTERN 2/3RDS OF THE CWA
LATE THIS AFTERNOON INTO THE EVENING HOURS. BOTH 00Z NAM AND 21Z
SREF PROBABILITIES INDICATE THE POTENTIAL FOR A RUMBLE OF THUNDER OR
TWO OVER THE SOUTHEAST PART OF THE CWA...WHICH CORRELATES WELL WITH
POCKET OF STEEPER 850-500MB LAPSE RATES MOVING THROUGH AND BEST
FORCING. PREVIOUS SHIFT HAD A SLIGHT CHANCE MENTIONED (WHICH SEEMS
REASONABLE) AND ONLY MADE MINOR TWEAKS.
ALL OF THE FORCING FEATURES WILL SHIFT NORTHEAST AROUND OR SHORTLY
AFTER MIDNIGHT (AND MID LEVEL DRYING OCCURS)...SO HAVE A DIMINISHING
TREND TO THE POPS FROM SOUTHWEST TO NORTHEAST. WITH THE DEEP
MOISTURE DEPARTING...DID TRANSITION THE PRECIP WORDING FROM RAIN TO
DRIZZLE OVERNIGHT (MAINLY OVER THE EASTERN AREAS). MODELS MATCH UP
WITH THAT IDEA (BLOTCHY LOOK TO QPF IN THE HIGHER RESOLUTION RUNS).
DID CONTINUE TO MENTION SOME FOG WITH THE RAIN THIS
EVENING...ALTHOUGH THE WIND MIGHT HELP KEEP IT MORE OF A
STRATUS WITH ONLY A SLIGHT LOWERING OF VISIBILITIES EXCEPT OVER THE
HIGHER TERRAIN. THUS...HAVE KEPT MOST OF THE AREA UNDER PATCHY
WORDING...ALTHOUGH DID IT DIMINISH OVER THE WEST OVERNIGHT AS
LOWER LEVEL AIR SLIDES IN.
FINALLY...WILL SEE INCREASING SOUTHERLY WINDS TODAY WITH A
TIGHTENING PRESSURE GRADIENT BETWEEN THE HIGH OFF THE EAST COAST AND
TROUGH MOVING EAST THROUGH MINNESOTA. STRONGEST WINDS WILL BE OVER
THE EASTERN CWA...WHERE THE LOW LEVEL JET WILL BE LOCATED. WITH THE
INCREASING LOW LEVEL MOISTURE AND EXPECTED CLOUD COVER...THINK THAT
WILL LIMIT MIXING AND KEEP WINDS IN CHECK (OCCASIONAL GUSTS IN THE
20-30MPH RANGE SEEN ON BUFKIT MOMENTUM TRANSFER). ABOVE NORMAL
TEMPERATURES WILL CONTINUE TODAY AND TONIGHT AS WARM AIR SLIDES
NORTH OVER THE AREA. THIS WARM AIR WILL REALLY SURGE IN
TONIGHT...WHICH COULD CAUSE MOST LOWS TO OCCUR EARLY THIS EVENING
AND THEN RISING OVERNIGHT INTO THE UPPER 40S AND AROUND 50.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 521 AM EST SAT NOV 16 2013
LONG TERM WILL START WITH A STRONG STORM SYSTEM LIFTING THRU THE
UPPER GREAT LAKES...BRINGING RAIN AND THEN A TRANSITION TO STRONG
WINDS...SNOW SHOWERS AND SEASONABLY COLD AIR. IT STILL LOOKS LIKE A
TREND TO LESS AMPLIFIED FLOW TOWARD THE MIDDLE OF NEXT WEEK. THAT
MAY ONLY BE SHORT-LIVED AS MEDIUM RANGE GUIDANCE IS NOW INDICATING A
SHARPER PROGRESSIVE TROF MOVING ACROSS THE NRN CONUS MID/LATE WEEK
RATHER THAN TROF REMAINING MORE CONFINED TO CANADA THAT HAD BEEN
INDICATED IN RECENT DAYS MODEL RUNS. END RESULT IS MODERATING TEMPS
AND A DRIER PATTERN HEADING INTO MID WEEK AND THEN A TURN TO COLDER
WEATHER LATE WEEK...ACCOMPANIED BY SOME -SHSN AND FOLLOWED BY
PROBABLY LIGHT LES OFF LAKE SUPERIOR.
BEGINNING SUN...ATTENTION WILL BE ON A STRONG SHORTWAVE SWINGING OUT
ACROSS THE CNTRL PLAINS. WAVE WILL GO NEGATIVE TILT AND RAPIDLY
DEEPEN AS IT PASSES ACROSS THE GREAT LAKES SUN NIGHT. 12HR 500MB
HEIGHT FALLS ARE STILL FCST TO MAX OUT AROUND AN IMPRESSIVE 280M TO
THE NE AND E OF GEORGIAN BAY. MAJORITY OF GUIDANCE STILL INDICATES
DEEPENING SFC LOW LIFTING NE THRU WI AND SE LAKE SUPERIOR...WHICH
WAS THE PREFERRED TRACK 24HRS AGO. THE GFS IS STILL THE OUTLIER WITH
A FARTHER E TRACK...PASSING ACROSS THE STRAITS AND DRUMMOND ISLAND.
IF ANYTHING...THE GFS HAS BEEN TRENDING VERY SLIGHTLY FARTHER S AND
E WITH THE TRACK IN RECENT RUNS. WILL CONTINUE TO USE THE MORE
CLIMATOLOGICALLY FAVORED SFC LOW TRACK ACROSS FAR SE LAKE
SUPERIOR...REPRESENTED BY THE ECMWF/UKMET/GEM AND 4KM NAM WINDOW.
INCREASING HEIGHT FALLS AND STRONG UPPER DIFFLUENCE WITH LEFT EXIT
OF 130KT UPPER JET NOSING INTO THE GREAT LAKES WILL SUPPORT AN AREA
OF SHRA SPREADING N INTO UPPER MI SUN AFTN...WITH THE HEAVIEST PCPN
PROBABLY SLIDING THRU CNTRL/ERN UPPER MI LATE AFTN/EVENING WHERE
LOW/MID LEVEL FRONTOGENESIS AND ISENTROPIC ASCENT ARE STRONGEST.
WITH SHOWALTER INDEX FALLING TO SLIGHTLY NEGATIVE...WILL CONTINUE A
MENTION OF THUNDER OVER ROUGHLY THE E HALF OF THE FCST AREA...
GENERALLY ALONG AND E OF EXPECTED SFC LOW TRACK. COLDER AIR WRAPPING
IN BEHIND THE SYSTEM WILL CHANGE RAIN TO SNOW RATHER QUICKLY FROM W
TO E DURING SUN NIGHT PER CONSENSUS OF MODEL THERMAL
FIELDS/SOUNDINGS. POTENTIAL FOR HVY SNOW OR EVEN MDT SNOW IS NOTABLY
DIMINISHED FROM WHAT SOME MODEL RUNS SUGGESTED IN RECENT DAYS.
BIGGEST PROBLEM IS TIMING OF HOW FAST DEFORMATION PCPN SHIELD
DEVELOPS/EXPANDS/ORGANIZES ON NW/W SIDE OF SYSTEM. WITH THE FAST
SPEED OF SHORTWAVE THRU THE WRN GREAT LAKES AND WITH SFC/MID LEVEL
SYSTEM NOT BECOMING WELL DEVELOPED UNTIL NE OF THE AREA...IT DOESN`T
APPEAR THE SYNOPTIC SNOW SHIELD WILL BECOME REALLY ORGANIZED UNTIL
IT MOVES INTO NRN ONTARIO TO THE N AND NE OF LAKE SUPERIOR. IT WILL
PROBABLY TURN INTO A FAIRLY SUBSTANTIAL SNOW STORM FOR AREAS BTWN
LAKE SUPERIOR AND JAMES BAY...ESPECIALLY TOWARD JAMES BAY.
AS IT APPEARS NOW...THE STEADIER/HEAVIER PCPN IN THE EVENING OVER
THE W WILL PROBABLY FALL MOSTLY AS RAIN. BY THE TIME COLUMN COOLS
SUFFICIENTLY FOR A CHANGEOVER TO SNOW...THE SYNOPTIC PCPN WILL BE
PULLING OUT. STILL...WITH CYCLONIC FLOW/850MB TEMPS FALLING TO
AROUND -9C BY 12Z MON AND DEEPER MOISTURE HANGING AROUND...EXPECT
LAKE ENHANCED SNOW TO DEVELOP OFF WRN LAKE SUPERIOR OVERNIGHT. MIGHT
SEE A FEW INCHES OF SNOW IN THE HIGHER TERRAIN OF THE W BY SUNRISE
MON...BUT WITH DENDRITIC SNOW GROWTH TEMPS ABOVE THE UPWARD MOTION
ZONE AND POTENTIALLY EVEN ABOVE THE MOIST LAYER...IT MAY BE TOUGH TO
GET A FEW INCHES OF SNOW. STRONG BOUNDARY LAYER WINDS SHOULD TEND TO
SPREAD THE LAKE ENHANCED SNOW A BIT FARTHER INLAND THAN IS USUALLY
THE CASE. HURON MTNS MAY BE AN AREA TO SEE MOST PERISTENT SNOWFALL.
LATE CHANGEOVER TO SNOW OVER THE E WILL FURTHER LIMIT SNOW
ACCUMULATIONS IN THAT AREA SUN NIGHT. NO HEADLINES PERTAINING TO
SNOW ARE WARRANTED AT THIS TIME.
WINDS WILL BE A BIG STORY WITH THE SYSTEM. IN THE WAKE OF THE
DEEPENING SFC LOW...MODELS INDICATE NW WINDS OF 45-55KT AT 850MB
DURING THE PERIOD OF CAA. 4KM HIGH RES NAM SHOWS WIND GUST POTENTIAL
TO A LITTLE OVER 40KT OVER THE KEWEENAW AND TO A LITTLE OVER 50KT
ALONG THE LAKESHORE E OF MARQUETTE. ISALLOBARIC WIND COMPONENT WILL
ADD SOME ENHANCEMENT AS PRES RISES STRENGTHEN OVER THE AREA IN THE
WAKE OF THE DEEPENING LOW. IF ADVY HEADLINES END UP NOT BEING NEEDED
FOR SNOWFALL...WIND HEADLINES WILL BE NEEDED. ON LAKE SUPERIOR...
HIGH GALES ARE LIKELY ON THE E HALF OF LAKE SUPERIOR WITH DECENT
POTENTIAL FOR A PERIOD OF STORM FORCE WINDS LATE OVERNIGHT SUN NIGHT
INTO MON MORNING.
TRANSITION TO PURE LES WILL OCCUR MON/MON NIGHT UNDER NW FLOW AS
850MB TEMPS FALL TO -10/-11C. LINGERING LIGHT LES WILL WIND DOWN/END
OVER WRN UPPER MI MON NIGHT AND OVER NCNTRL UPPER MI TUE MORNING AS
AS FLOW BACKS AND WAA GETS UNDERWAY. WITH SFC HIGH PRES RIDGE
REACHING WRN UPPER MI LATE MON NIGHT...TEMPS COULD PLUMMET IF CLOUDS
CLEAR OUT. NONE OF THE GUIDANCE IS ESPECIALLY COLD. LOWEST GUIDANCE
GENERALLY SUGGEST MINS IN THE UPPER TEENS...AND FCST WILL REFLECT
THESE COLDER NUMBERS.
WAA WED MIGHT YIELD SOME LIGHT PCPN AT THAT TIME. THEN...STRONG
SHORTWAVE MOVING ACROSS SRN CANADA WILL SWEEP ASSOCIATED COLD FRONT
ACROSS THE AREA WED NIGHT...ACCOMPANIED BY SOME -RA/-SN. LES MAY GET
UNDERWAY THU...BUT MODELS HAVE NOT BEEN VERY CONSISTENT ON THE
INTENSITY OF THE COLD FOLLOWING THE FRONT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 121 PM EST SAT NOV 16 2013
ON FAVORABLE S WINDS WITH APPROACHING LOW LEVEL MOISTURE...CEILINGS
AT SAW QUICKLY FELL INTO THE IFR CATEGORY ...WHERE THEY WILL PRETTY
MUCH STAY /IFR TO LIFR/ THROUGH SUNDAY MORNING. AT THE OTHER
SITES...THE LOWER CLOUDS HAVE BEEN SLOWER TO ARRIVE...WITH IFR OR
MVFR CEILINGS EXPECTED TO SET IN THROUGH 09Z SUNDAY. SAW IS CLOSE TO
LLWS CRITERIA FROM 23Z SATURDAY THROUGH 06Z SUNDAY. HOWEVER...WITH
SFC WINDS STAYING UP WITH GUSTS ON THE ORDER OF 20-25KTS...WILL
EXCLUDE THE MENTION OF LLWS AT THIS TIME. RAIN WILL BE THE MAIN
WEATHER TYPE. LOOKING FARTHER AHEAD...EXPECT STRONG NW WINDS TO PUSH
IN BEHIND THE EXITING SFC LOW AFTER 00Z MONDAY. THE STRONGEST WINDS
WITH GUSTS NEAR 30KTS AT CMX AND TO A LESS EXTENT SAW...CONTINUING
THROUGH MID MORNING MONDAY.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 521 AM EST SAT NOV 16 2013
SOUTH WINDS WILL INCREASE TO 30KT TODAY AHEAD OF DEEPENING SFC LOW
MOVING FROM THE PLAINS TOWARD THE UPPER MISSISSIPPI VALLEY.
STRONGEST WINDS TODAY/TONIGHT WILL BE OVER EASTERN PORTIONS OF LAKE
SUPERIOR...WHERE THERE MAY BE A FEW GALE GUSTS TO 35KT. STABLE
LOW-LEVEL TEMPERATURE PROFILE AND LACK OF PRESSURE FALLS TO NORTH OF
LAKE SUPERIOR SHOULD LIMIT FREQUENCY OF GUSTS. WINDS WILL DIMINISH
FOR A TIME SUNDAY AS SFC TROF DRIFTS OVERHEAD AND PRES GRADIENT
WEAKENS CONSIDERABLY. NEW LOW PRESSURE ORGANIZING OVER THE PLAINS
WILL THEN LIFT NE ALONG THE TROF AND RAPIDLY DEEPEN AS IT PASSES
ACROSS FAR SE LAKE SUPERIOR INTO NRN ONTARIO. PRES WILL LIKELY FALL
BLO 975MB OR 29.0 INCHES AS IT MOVES N OF THE LAKE SUNDAY NIGHT/MON
MORNING. IN THE NW FLOW IN THE WAKE OF THE DEEPENING LOW PRES...
GALES WILL OCCUR ACROSS ALL BUT FAR WRN LAKE SUPERIOR WITH HIGH END
GALES TO STORM FORCE WINDS LIKELY SUN NIGHT/MON MORNING OVER THE E
HALF. GIVEN STORM POTENTIAL...A STORM WATCH HAS BEEN ISSUED FOR THE
E HALF OF LAKE SUPERIOR. WINDS WILL DIMINISH BELOW 30KT FROM W TO E
MON NIGHT...AND A PERIOD OF LIGHT WINDS UNDER 15KT SHOULD OCCUR TUE
AS HIGH PRES RIDGE PASSES ACROSS LAKE SUPERIOR. S WINDS WILL THEN
RAMP UP TO 20-30KT FOR WED BEHIND THE HIGH AND AHEAD OF THE NEXT
APPROACHING LOW PRES TROF.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
STORM WATCH FROM SUNDAY EVENING THROUGH MONDAY AFTERNOON FOR
LSZ248>251-265>267.
GALE WATCH FROM SUNDAY EVENING THROUGH MONDAY AFTERNOON FOR
LSZ241>245-263-264.
LAKE MICHIGAN...
GALE WATCH FROM SUNDAY EVENING THROUGH MONDAY MORNING FOR LMZ221-
248-250.
&&
$$
SHORT TERM...SRF
LONG TERM...ROLFSON
AVIATION...KF
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
646 AM EST SAT NOV 16 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 521 AM EST SAT NOV 16 2013
SOUTHWESTERLY FLOW IS BEGINNING TO INCREASE OVER THE CWA AS THE
UPPER TROUGH AMPLIFIES DUE TO A STRONG SHORTWAVE MOVING SOUTHEAST
THROUGH THE PACIFIC NORTHWEST. THIS SHORTWAVE WILL BE THE MAJOR
PLAYER TO OUR WEATHER FOR THE SECOND HALF OF THE WEEKEND.
FOR THE SHORT TERM...THE SOUTHWESTERLY FLOW ALOFT WILL ALLOW A
SHORTWAVE CURRENTLY LOCATED NEAR THE FOUR CORNERS REGION TO MOVE
NORTHEAST ACROSS THE UPPER GREAT LAKES LATE THIS AFTERNOON AND
EVENING. MOISTURE STREAMING NORTHEAST ON WV IMAGERY IS LEADING TO
SOME HIGH CLOUDS OVER MUCH OF UPPER MICHIGAN. IN THE LOWER
LEVELS...INITIAL RAP SOUNDINGS SHOWING PLENTY OF DRY AIR BELOW THE
HIGH CLOUDS BUT THERE WAS ENOUGH RADIATIONAL COOLING EARLIER
THIS EVENING TO PRODUCE SOME PATCHY FOG OVER CENTRAL/EASTERN
UPPER MICHIGAN. THE DRIER LOW LEVELS WILL LIKELY BE SHORT LIVED
AS 3-5KFT CEILINGS COVER MUCH OF CENTRAL/NORTHERN WISCONSIN AND WILL
BE MOVING INTO THE AREA OVER THE NEXT COUPLE OF HOURS. IN ADDITION
TO THOSE CLOUDS...MODELS ARE SHOWING THE DEVELOPING 1KFT CEILINGS
IN NORTHERN ILLINOIS TO QUICKLY LIFT NORTH AND EXPAND THIS MORNING
AND EARLY AFTERNOON...COVERING MUCH OF UPPER MICHIGAN.
THE SHORTWAVE WILL BE NEARING THE REGION THIS AFTERNOON AND THERE
ARE SEVERAL FEATURES SUPPORTING A BROAD AREA OF RAIN MOVING THROUGH
THE AREA LATE THIS AFTERNOON AND EVENING. FIRST...EXPECT THERE TO
BE A WEAK COUPLED JET STRUCTURE OVER THE AREA THIS EVENING. BROAD
MID LEVEL WARM AIR ADVECTION AND MOISTURE TRANSPORT WILL ACCOMPANY
THIS SHORTWAVE...WITH THE EASTERN CWA SEEING THE BEST OF BOTH
FEATURES. AT THE SURFACE...THE BROAD LOW DEVELOPING OVER THE
CENTRAL/NORTHERN PLAINS WILL SLIDE A TROUGH THROUGH MINNESOTA TODAY
AND OVER WESTERN LAKE SUPERIOR TONIGHT. HAVE HIGH CONFIDENCE IN THE
FORECAST FOR THIS AFTERNOON/EVENING BASED OFF GREAT MODEL
CONSISTENCY. SINCE THE BEST FORCING IS OVER THE SOUTHEAST
HALF...WILL HAVE THE HIGHEST POPS/QPF IN THAT AREA BUT THERE WILL BE
A PERIOD OF DEFINITE POPS OVER THE ENTIRE AREA. AS FOR QPF...EXPECT
VALUES TO RANGE FROM 0.2 OVER THE WEST TO 0.75IN OVER THE
EAST...WITH SOME HIGHER AMOUNTS IF THERE ARE SOME EMBEDDED
THUNDERSTORMS.
AS FOR THUNDER...THERE IS A POCKET OF 50-125J/KG OF MUCAPE AND
SHOWALTER VALUES SLIGHTLY BELOW 0 OVER THE EASTERN 2/3RDS OF THE CWA
LATE THIS AFTERNOON INTO THE EVENING HOURS. BOTH 00Z NAM AND 21Z
SREF PROBABILITIES INDICATE THE POTENTIAL FOR A RUMBLE OF THUNDER OR
TWO OVER THE SOUTHEAST PART OF THE CWA...WHICH CORRELATES WELL WITH
POCKET OF STEEPER 850-500MB LAPSE RATES MOVING THROUGH AND BEST
FORCING. PREVIOUS SHIFT HAD A SLIGHT CHANCE MENTIONED (WHICH SEEMS
REASONABLE) AND ONLY MADE MINOR TWEAKS.
ALL OF THE FORCING FEATURES WILL SHIFT NORTHEAST AROUND OR SHORTLY
AFTER MIDNIGHT (AND MID LEVEL DRYING OCCURS)...SO HAVE A DIMINISHING
TREND TO THE POPS FROM SOUTHWEST TO NORTHEAST. WITH THE DEEP
MOISTURE DEPARTING...DID TRANSITION THE PRECIP WORDING FROM RAIN TO
DRIZZLE OVERNIGHT (MAINLY OVER THE EASTERN AREAS). MODELS MATCH UP
WITH THAT IDEA (BLOTCHY LOOK TO QPF IN THE HIGHER RESOLUTION RUNS).
DID CONTINUE TO MENTION SOME FOG WITH THE RAIN THIS
EVENING...ALTHOUGH THE WIND MIGHT HELP KEEP IT MORE OF A
STRATUS WITH ONLY A SLIGHT LOWERING OF VISIBILITIES EXCEPT OVER THE
HIGHER TERRAIN. THUS...HAVE KEPT MOST OF THE AREA UNDER PATCHY
WORDING...ALTHOUGH DID IT DIMINISH OVER THE WEST OVERNIGHT AS
LOWER LEVEL AIR SLIDES IN.
FINALLY...WILL SEE INCREASING SOUTHERLY WINDS TODAY WITH A
TIGHTENING PRESSURE GRADIENT BETWEEN THE HIGH OFF THE EAST COAST AND
TROUGH MOVING EAST THROUGH MINNESOTA. STRONGEST WINDS WILL BE OVER
THE EASTERN CWA...WHERE THE LOW LEVEL JET WILL BE LOCATED. WITH THE
INCREASING LOW LEVEL MOISTURE AND EXPECTED CLOUD COVER...THINK THAT
WILL LIMIT MIXING AND KEEP WINDS IN CHECK (OCCASIONAL GUSTS IN THE
20-30MPH RANGE SEEN ON BUFKIT MOMENTUM TRANSFER). ABOVE NORMAL
TEMPERATURES WILL CONTINUE TODAY AND TONIGHT AS WARM AIR SLIDES
NORTH OVER THE AREA. THIS WARM AIR WILL REALLY SURGE IN
TONIGHT...WHICH COULD CAUSE MOST LOWS TO OCCUR EARLY THIS EVENING
AND THEN RISING OVERNIGHT INTO THE UPPER 40S AND AROUND 50.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 521 AM EST SAT NOV 16 2013
LONG TERM WILL START WITH A STRONG STORM SYSTEM LIFTING THRU THE
UPPER GREAT LAKES...BRINGING RAIN AND THEN A TRANSITION TO STRONG
WINDS...SNOW SHOWERS AND SEASONABLY COLD AIR. IT STILL LOOKS LIKE A
TREND TO LESS AMPLIFIED FLOW TOWARD THE MIDDLE OF NEXT WEEK. THAT
MAY ONLY BE SHORT-LIVED AS MEDIUM RANGE GUIDANCE IS NOW INDICATING A
SHARPER PROGRESSIVE TROF MOVING ACROSS THE NRN CONUS MID/LATE WEEK
RATHER THAN TROF REMAINING MORE CONFINED TO CANADA THAT HAD BEEN
INDICATED IN RECENT DAYS MODEL RUNS. END RESULT IS MODERATING TEMPS
AND A DRIER PATTERN HEADING INTO MID WEEK AND THEN A TURN TO COLDER
WEATHER LATE WEEK...ACCOMPANIED BY SOME -SHSN AND FOLLOWED BY
PROBABLY LIGHT LES OFF LAKE SUPERIOR.
BEGINNING SUN...ATTENTION WILL BE ON A STRONG SHORTWAVE SWINGING OUT
ACROSS THE CNTRL PLAINS. WAVE WILL GO NEGATIVE TILT AND RAPIDLY
DEEPEN AS IT PASSES ACROSS THE GREAT LAKES SUN NIGHT. 12HR 500MB
HEIGHT FALLS ARE STILL FCST TO MAX OUT AROUND AN IMPRESSIVE 280M TO
THE NE AND E OF GEORGIAN BAY. MAJORITY OF GUIDANCE STILL INDICATES
DEEPENING SFC LOW LIFTING NE THRU WI AND SE LAKE SUPERIOR...WHICH
WAS THE PREFERRED TRACK 24HRS AGO. THE GFS IS STILL THE OUTLIER WITH
A FARTHER E TRACK...PASSING ACROSS THE STRAITS AND DRUMMOND ISLAND.
IF ANYTHING...THE GFS HAS BEEN TRENDING VERY SLIGHTLY FARTHER S AND
E WITH THE TRACK IN RECENT RUNS. WILL CONTINUE TO USE THE MORE
CLIMATOLOGICALLY FAVORED SFC LOW TRACK ACROSS FAR SE LAKE
SUPERIOR...REPRESENTED BY THE ECMWF/UKMET/GEM AND 4KM NAM WINDOW.
INCREASING HEIGHT FALLS AND STRONG UPPER DIFFLUENCE WITH LEFT EXIT
OF 130KT UPPER JET NOSING INTO THE GREAT LAKES WILL SUPPORT AN AREA
OF SHRA SPREADING N INTO UPPER MI SUN AFTN...WITH THE HEAVIEST PCPN
PROBABLY SLIDING THRU CNTRL/ERN UPPER MI LATE AFTN/EVENING WHERE
LOW/MID LEVEL FRONTOGENESIS AND ISENTROPIC ASCENT ARE STRONGEST.
WITH SHOWALTER INDEX FALLING TO SLIGHTLY NEGATIVE...WILL CONTINUE A
MENTION OF THUNDER OVER ROUGHLY THE E HALF OF THE FCST AREA...
GENERALLY ALONG AND E OF EXPECTED SFC LOW TRACK. COLDER AIR WRAPPING
IN BEHIND THE SYSTEM WILL CHANGE RAIN TO SNOW RATHER QUICKLY FROM W
TO E DURING SUN NIGHT PER CONSENSUS OF MODEL THERMAL
FIELDS/SOUNDINGS. POTENTIAL FOR HVY SNOW OR EVEN MDT SNOW IS NOTABLY
DIMINISHED FROM WHAT SOME MODEL RUNS SUGGESTED IN RECENT DAYS.
BIGGEST PROBLEM IS TIMING OF HOW FAST DEFORMATION PCPN SHIELD
DEVELOPS/EXPANDS/ORGANIZES ON NW/W SIDE OF SYSTEM. WITH THE FAST
SPEED OF SHORTWAVE THRU THE WRN GREAT LAKES AND WITH SFC/MID LEVEL
SYSTEM NOT BECOMING WELL DEVELOPED UNTIL NE OF THE AREA...IT DOESN`T
APPEAR THE SYNOPTIC SNOW SHIELD WILL BECOME REALLY ORGANIZED UNTIL
IT MOVES INTO NRN ONTARIO TO THE N AND NE OF LAKE SUPERIOR. IT WILL
PROBABLY TURN INTO A FAIRLY SUBSTANTIAL SNOW STORM FOR AREAS BTWN
LAKE SUPERIOR AND JAMES BAY...ESPECIALLY TOWARD JAMES BAY.
AS IT APPEARS NOW...THE STEADIER/HEAVIER PCPN IN THE EVENING OVER
THE W WILL PROBABLY FALL MOSTLY AS RAIN. BY THE TIME COLUMN COOLS
SUFFICIENTLY FOR A CHANGEOVER TO SNOW...THE SYNOPTIC PCPN WILL BE
PULLING OUT. STILL...WITH CYCLONIC FLOW/850MB TEMPS FALLING TO
AROUND -9C BY 12Z MON AND DEEPER MOISTURE HANGING AROUND...EXPECT
LAKE ENHANCED SNOW TO DEVELOP OFF WRN LAKE SUPERIOR OVERNIGHT. MIGHT
SEE A FEW INCHES OF SNOW IN THE HIGHER TERRAIN OF THE W BY SUNRISE
MON...BUT WITH DENDRITIC SNOW GROWTH TEMPS ABOVE THE UPWARD MOTION
ZONE AND POTENTIALLY EVEN ABOVE THE MOIST LAYER...IT MAY BE TOUGH TO
GET A FEW INCHES OF SNOW. STRONG BOUNDARY LAYER WINDS SHOULD TEND TO
SPREAD THE LAKE ENHANCED SNOW A BIT FARTHER INLAND THAN IS USUALLY
THE CASE. HURON MTNS MAY BE AN AREA TO SEE MOST PERISTENT SNOWFALL.
LATE CHANGEOVER TO SNOW OVER THE E WILL FURTHER LIMIT SNOW
ACCUMULATIONS IN THAT AREA SUN NIGHT. NO HEADLINES PERTAINING TO
SNOW ARE WARRANTED AT THIS TIME.
WINDS WILL BE A BIG STORY WITH THE SYSTEM. IN THE WAKE OF THE
DEEPENING SFC LOW...MODELS INDICATE NW WINDS OF 45-55KT AT 850MB
DURING THE PERIOD OF CAA. 4KM HIGH RES NAM SHOWS WIND GUST POTENTIAL
TO A LITTLE OVER 40KT OVER THE KEWEENAW AND TO A LITTLE OVER 50KT
ALONG THE LAKESHORE E OF MARQUETTE. ISALLOBARIC WIND COMPONENT WILL
ADD SOME ENHANCEMENT AS PRES RISES STRENGTHEN OVER THE AREA IN THE
WAKE OF THE DEEPENING LOW. IF ADVY HEADLINES END UP NOT BEING NEEDED
FOR SNOWFALL...WIND HEADLINES WILL BE NEEDED. ON LAKE SUPERIOR...
HIGH GALES ARE LIKELY ON THE E HALF OF LAKE SUPERIOR WITH DECENT
POTENTIAL FOR A PERIOD OF STORM FORCE WINDS LATE OVERNIGHT SUN NIGHT
INTO MON MORNING.
TRANSITION TO PURE LES WILL OCCUR MON/MON NIGHT UNDER NW FLOW AS
850MB TEMPS FALL TO -10/-11C. LINGERING LIGHT LES WILL WIND DOWN/END
OVER WRN UPPER MI MON NIGHT AND OVER NCNTRL UPPER MI TUE MORNING AS
AS FLOW BACKS AND WAA GETS UNDERWAY. WITH SFC HIGH PRES RIDGE
REACHING WRN UPPER MI LATE MON NIGHT...TEMPS COULD PLUMMET IF CLOUDS
CLEAR OUT. NONE OF THE GUIDANCE IS ESPECIALLY COLD. LOWEST GUIDANCE
GENERALLY SUGGEST MINS IN THE UPPER TEENS...AND FCST WILL REFLECT
THESE COLDER NUMBERS.
WAA WED MIGHT YIELD SOME LIGHT PCPN AT THAT TIME. THEN...STRONG
SHORTWAVE MOVING ACROSS SRN CANADA WILL SWEEP ASSOCIATED COLD FRONT
ACROSS THE AREA WED NIGHT...ACCOMPANIED BY SOME -RA/-SN. LES MAY GET
UNDERWAY THU...BUT MODELS HAVE NOT BEEN VERY CONSISTENT ON THE
INTENSITY OF THE COLD FOLLOWING THE FRONT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 644 AM EST SAT NOV 16 2013
SOUTHERLY WINDS WILL INCREASE LOW LEVEL MOISTURE ACROSS UPPER
MICHIGAN TODAY AHEAD OF A DISTURBANCE MOVING THROUGH THIS EVENING.
THIS INCREASING LOW LEVEL MOISTURE WILL PRODUCE A QUICK TRANSITION
FROM VFR CONDITIONS TO IFR CEILINGS THIS AFTERNOON. THEN THE
APPROACHING DISTURBANCE WILL BRING A WIDE SWATH OF RAIN THIS
EVENING AND LEAD TO LOWER CEILINGS AND VISIBILITIES...ESPECIALLY AT
KSAW WHERE THEY WILL BE BORDERLINE AIRFIELD LANDING MINS. MODELS ARE
SHOWING DRIER AIR ARRIVING OVER THE WEST AFTER MIDNIGHT AND HAVE
TRENDED CEILINGS UP AS THE RAIN ENDS. KSAW WILL HAVE THE LOW
CEILINGS REMAINING THROUGH MUCH OF THE NIGHT BUT EXPECT CONDITIONS
TO TRY TO IMPROVE BY DAYBREAK.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 521 AM EST SAT NOV 16 2013
SOUTH WINDS WILL INCREASE TO 30KT TODAY AHEAD OF DEEPENING SFC LOW
MOVING FROM THE PLAINS TOWARD THE UPPER MISSISSIPPI VALLEY.
STRONGEST WINDS TODAY/TONIGHT WILL BE OVER EASTERN PORTIONS OF LAKE
SUPERIOR...WHERE THERE MAY BE A FEW GALE GUSTS TO 35KT. STABLE
LOW-LEVEL TEMPERATURE PROFILE AND LACK OF PRESSURE FALLS TO NORTH OF
LAKE SUPERIOR SHOULD LIMIT FREQUENCY OF GUSTS. WINDS WILL DIMINISH
FOR A TIME SUNDAY AS SFC TROF DRIFTS OVERHEAD AND PRES GRADIENT
WEAKENS CONSIDERABLY. NEW LOW PRESSURE ORGANIZING OVER THE PLAINS
WILL THEN LIFT NE ALONG THE TROF AND RAPIDLY DEEPEN AS IT PASSES
ACROSS FAR SE LAKE SUPERIOR INTO NRN ONTARIO. PRES WILL LIKELY FALL
BLO 975MB OR 29.0 INCHES AS IT MOVES N OF THE LAKE SUNDAY NIGHT/MON
MORNING. IN THE NW FLOW IN THE WAKE OF THE DEEPENING LOW PRES...
GALES WILL OCCUR ACROSS ALL BUT FAR WRN LAKE SUPERIOR WITH HIGH END
GALES TO STORM FORCE WINDS LIKELY SUN NIGHT/MON MORNING OVER THE E
HALF. GIVEN STORM POTENTIAL...A STORM WATCH HAS BEEN ISSUED FOR THE
E HALF OF LAKE SUPERIOR. WINDS WILL DIMINISH BELOW 30KT FROM W TO E
MON NIGHT...AND A PERIOD OF LIGHT WINDS UNDER 15KT SHOULD OCCUR TUE
AS HIGH PRES RIDGE PASSES ACROSS LAKE SUPERIOR. S WINDS WILL THEN
RAMP UP TO 20-30KT FOR WED BEHIND THE HIGH AND AHEAD OF THE NEXT
APPROACHING LOW PRES TROF.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
STORM WATCH FROM SUNDAY EVENING THROUGH MONDAY AFTERNOON FOR
LSZ248>251-265>267.
GALE WATCH FROM SUNDAY EVENING THROUGH MONDAY AFTERNOON FOR
LSZ241>245-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...ROLFSON
AVIATION...SRF
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
522 AM EST SAT NOV 16 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 521 AM EST SAT NOV 16 2013
SOUTHWESTERLY FLOW IS BEGINNING TO INCREASE OVER THE CWA AS THE
UPPER TROUGH AMPLIFIES DUE TO A STRONG SHORTWAVE MOVING SOUTHEAST
THROUGH THE PACIFIC NORTHWEST. THIS SHORTWAVE WILL BE THE MAJOR
PLAYER TO OUR WEATHER FOR THE SECOND HALF OF THE WEEKEND.
FOR THE SHORT TERM...THE SOUTHWESTERLY FLOW ALOFT WILL ALLOW A
SHORTWAVE CURRENTLY LOCATED NEAR THE FOUR CORNERS REGION TO MOVE
NORTHEAST ACROSS THE UPPER GREAT LAKES LATE THIS AFTERNOON AND
EVENING. MOISTURE STREAMING NORTHEAST ON WV IMAGERY IS LEADING TO
SOME HIGH CLOUDS OVER MUCH OF UPPER MICHIGAN. IN THE LOWER
LEVELS...INITIAL RAP SOUNDINGS SHOWING PLENTY OF DRY AIR BELOW THE
HIGH CLOUDS BUT THERE WAS ENOUGH RADIATIONAL COOLING EARLIER
THIS EVENING TO PRODUCE SOME PATCHY FOG OVER CENTRAL/EASTERN
UPPER MICHIGAN. THE DRIER LOW LEVELS WILL LIKELY BE SHORT LIVED
AS 3-5KFT CEILINGS COVER MUCH OF CENTRAL/NORTHERN WISCONSIN AND WILL
BE MOVING INTO THE AREA OVER THE NEXT COUPLE OF HOURS. IN ADDITION
TO THOSE CLOUDS...MODELS ARE SHOWING THE DEVELOPING 1KFT CEILINGS
IN NORTHERN ILLINOIS TO QUICKLY LIFT NORTH AND EXPAND THIS MORNING
AND EARLY AFTERNOON...COVERING MUCH OF UPPER MICHIGAN.
THE SHORTWAVE WILL BE NEARING THE REGION THIS AFTERNOON AND THERE
ARE SEVERAL FEATURES SUPPORTING A BROAD AREA OF RAIN MOVING THROUGH
THE AREA LATE THIS AFTERNOON AND EVENING. FIRST...EXPECT THERE TO
BE A WEAK COUPLED JET STRUCTURE OVER THE AREA THIS EVENING. BROAD
MID LEVEL WARM AIR ADVECTION AND MOISTURE TRANSPORT WILL ACCOMPANY
THIS SHORTWAVE...WITH THE EASTERN CWA SEEING THE BEST OF BOTH
FEATURES. AT THE SURFACE...THE BROAD LOW DEVELOPING OVER THE
CENTRAL/NORTHERN PLAINS WILL SLIDE A TROUGH THROUGH MINNESOTA TODAY
AND OVER WESTERN LAKE SUPERIOR TONIGHT. HAVE HIGH CONFIDENCE IN THE
FORECAST FOR THIS AFTERNOON/EVENING BASED OFF GREAT MODEL
CONSISTENCY. SINCE THE BEST FORCING IS OVER THE SOUTHEAST
HALF...WILL HAVE THE HIGHEST POPS/QPF IN THAT AREA BUT THERE WILL BE
A PERIOD OF DEFINITE POPS OVER THE ENTIRE AREA. AS FOR QPF...EXPECT
VALUES TO RANGE FROM 0.2 OVER THE WEST TO 0.75IN OVER THE
EAST...WITH SOME HIGHER AMOUNTS IF THERE ARE SOME EMBEDDED
THUNDERSTORMS.
AS FOR THUNDER...THERE IS A POCKET OF 50-125J/KG OF MUCAPE AND
SHOWALTER VALUES SLIGHTLY BELOW 0 OVER THE EASTERN 2/3RDS OF THE CWA
LATE THIS AFTERNOON INTO THE EVENING HOURS. BOTH 00Z NAM AND 21Z
SREF PROBABILITIES INDICATE THE POTENTIAL FOR A RUMBLE OF THUNDER OR
TWO OVER THE SOUTHEAST PART OF THE CWA...WHICH CORRELATES WELL WITH
POCKET OF STEEPER 850-500MB LAPSE RATES MOVING THROUGH AND BEST
FORCING. PREVIOUS SHIFT HAD A SLIGHT CHANCE MENTIONED (WHICH SEEMS
REASONABLE) AND ONLY MADE MINOR TWEAKS.
ALL OF THE FORCING FEATURES WILL SHIFT NORTHEAST AROUND OR SHORTLY
AFTER MIDNIGHT (AND MID LEVEL DRYING OCCURS)...SO HAVE A DIMINISHING
TREND TO THE POPS FROM SOUTHWEST TO NORTHEAST. WITH THE DEEP
MOISTURE DEPARTING...DID TRANSITION THE PRECIP WORDING FROM RAIN TO
DRIZZLE OVERNIGHT (MAINLY OVER THE EASTERN AREAS). MODELS MATCH UP
WITH THAT IDEA (BLOTCHY LOOK TO QPF IN THE HIGHER RESOLUTION RUNS).
DID CONTINUE TO MENTION SOME FOG WITH THE RAIN THIS
EVENING...ALTHOUGH THE WIND MIGHT HELP KEEP IT MORE OF A
STRATUS WITH ONLY A SLIGHT LOWERING OF VISIBILITIES EXCEPT OVER THE
HIGHER TERRAIN. THUS...HAVE KEPT MOST OF THE AREA UNDER PATCHY
WORDING...ALTHOUGH DID IT DIMINISH OVER THE WEST OVERNIGHT AS
LOWER LEVEL AIR SLIDES IN.
FINALLY...WILL SEE INCREASING SOUTHERLY WINDS TODAY WITH A
TIGHTENING PRESSURE GRADIENT BETWEEN THE HIGH OFF THE EAST COAST AND
TROUGH MOVING EAST THROUGH MINNESOTA. STRONGEST WINDS WILL BE OVER
THE EASTERN CWA...WHERE THE LOW LEVEL JET WILL BE LOCATED. WITH THE
INCREASING LOW LEVEL MOISTURE AND EXPECTED CLOUD COVER...THINK THAT
WILL LIMIT MIXING AND KEEP WINDS IN CHECK (OCCASIONAL GUSTS IN THE
20-30MPH RANGE SEEN ON BUFKIT MOMENTUM TRANSFER). ABOVE NORMAL
TEMPERATURES WILL CONTINUE TODAY AND TONIGHT AS WARM AIR SLIDES
NORTH OVER THE AREA. THIS WARM AIR WILL REALLY SURGE IN
TONIGHT...WHICH COULD CAUSE MOST LOWS TO OCCUR EARLY THIS EVENING
AND THEN RISING OVERNIGHT INTO THE UPPER 40S AND AROUND 50.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 521 AM EST SAT NOV 16 2013
LONG TERM WILL START WITH A STRONG STORM SYSTEM LIFTING THRU THE
UPPER GREAT LAKES...BRINGING RAIN AND THEN A TRANSITION TO STRONG
WINDS...SNOW SHOWERS AND SEASONABLY COLD AIR. IT STILL LOOKS LIKE A
TREND TO LESS AMPLIFIED FLOW TOWARD THE MIDDLE OF NEXT WEEK. THAT
MAY ONLY BE SHORT-LIVED AS MEDIUM RANGE GUIDANCE IS NOW INDICATING A
SHARPER PROGRESSIVE TROF MOVING ACROSS THE NRN CONUS MID/LATE WEEK
RATHER THAN TROF REMAINING MORE CONFINED TO CANADA THAT HAD BEEN
INDICATED IN RECENT DAYS MODEL RUNS. END RESULT IS MODERATING TEMPS
AND A DRIER PATTERN HEADING INTO MID WEEK AND THEN A TURN TO COLDER
WEATHER LATE WEEK...ACCOMPANIED BY SOME -SHSN AND FOLLOWED BY
PROBABLY LIGHT LES OFF LAKE SUPERIOR.
BEGINNING SUN...ATTENTION WILL BE ON A STRONG SHORTWAVE SWINGING OUT
ACROSS THE CNTRL PLAINS. WAVE WILL GO NEGATIVE TILT AND RAPIDLY
DEEPEN AS IT PASSES ACROSS THE GREAT LAKES SUN NIGHT. 12HR 500MB
HEIGHT FALLS ARE STILL FCST TO MAX OUT AROUND AN IMPRESSIVE 280M TO
THE NE AND E OF GEORGIAN BAY. MAJORITY OF GUIDANCE STILL INDICATES
DEEPENING SFC LOW LIFTING NE THRU WI AND SE LAKE SUPERIOR...WHICH
WAS THE PREFERRED TRACK 24HRS AGO. THE GFS IS STILL THE OUTLIER WITH
A FARTHER E TRACK...PASSING ACROSS THE STRAITS AND DRUMMOND ISLAND.
IF ANYTHING...THE GFS HAS BEEN TRENDING VERY SLIGHTLY FARTHER S AND
E WITH THE TRACK IN RECENT RUNS. WILL CONTINUE TO USE THE MORE
CLIMATOLOGICALLY FAVORED SFC LOW TRACK ACROSS FAR SE LAKE
SUPERIOR...REPRESENTED BY THE ECMWF/UKMET/GEM AND 4KM NAM WINDOW.
INCREASING HEIGHT FALLS AND STRONG UPPER DIFFLUENCE WITH LEFT EXIT
OF 130KT UPPER JET NOSING INTO THE GREAT LAKES WILL SUPPORT AN AREA
OF SHRA SPREADING N INTO UPPER MI SUN AFTN...WITH THE HEAVIEST PCPN
PROBABLY SLIDING THRU CNTRL/ERN UPPER MI LATE AFTN/EVENING WHERE
LOW/MID LEVEL FRONTOGENESIS AND ISENTROPIC ASCENT ARE STRONGEST.
WITH SHOWALTER INDEX FALLING TO SLIGHTLY NEGATIVE...WILL CONTINUE A
MENTION OF THUNDER OVER ROUGHLY THE E HALF OF THE FCST AREA...
GENERALLY ALONG AND E OF EXPECTED SFC LOW TRACK. COLDER AIR WRAPPING
IN BEHIND THE SYSTEM WILL CHANGE RAIN TO SNOW RATHER QUICKLY FROM W
TO E DURING SUN NIGHT PER CONSENSUS OF MODEL THERMAL
FIELDS/SOUNDINGS. POTENTIAL FOR HVY SNOW OR EVEN MDT SNOW IS NOTABLY
DIMINISHED FROM WHAT SOME MODEL RUNS SUGGESTED IN RECENT DAYS.
BIGGEST PROBLEM IS TIMING OF HOW FAST DEFORMATION PCPN SHIELD
DEVELOPS/EXPANDS/ORGANIZES ON NW/W SIDE OF SYSTEM. WITH THE FAST
SPEED OF SHORTWAVE THRU THE WRN GREAT LAKES AND WITH SFC/MID LEVEL
SYSTEM NOT BECOMING WELL DEVELOPED UNTIL NE OF THE AREA...IT DOESN`T
APPEAR THE SYNOPTIC SNOW SHIELD WILL BECOME REALLY ORGANIZED UNTIL
IT MOVES INTO NRN ONTARIO TO THE N AND NE OF LAKE SUPERIOR. IT WILL
PROBABLY TURN INTO A FAIRLY SUBSTANTIAL SNOW STORM FOR AREAS BTWN
LAKE SUPERIOR AND JAMES BAY...ESPECIALLY TOWARD JAMES BAY.
AS IT APPEARS NOW...THE STEADIER/HEAVIER PCPN IN THE EVENING OVER
THE W WILL PROBABLY FALL MOSTLY AS RAIN. BY THE TIME COLUMN COOLS
SUFFICIENTLY FOR A CHANGEOVER TO SNOW...THE SYNOPTIC PCPN WILL BE
PULLING OUT. STILL...WITH CYCLONIC FLOW/850MB TEMPS FALLING TO
AROUND -9C BY 12Z MON AND DEEPER MOISTURE HANGING AROUND...EXPECT
LAKE ENHANCED SNOW TO DEVELOP OFF WRN LAKE SUPERIOR OVERNIGHT. MIGHT
SEE A FEW INCHES OF SNOW IN THE HIGHER TERRAIN OF THE W BY SUNRISE
MON...BUT WITH DENDRITIC SNOW GROWTH TEMPS ABOVE THE UPWARD MOTION
ZONE AND POTENTIALLY EVEN ABOVE THE MOIST LAYER...IT MAY BE TOUGH TO
GET A FEW INCHES OF SNOW. STRONG BOUNDARY LAYER WINDS SHOULD TEND TO
SPREAD THE LAKE ENHANCED SNOW A BIT FARTHER INLAND THAN IS USUALLY
THE CASE. HURON MTNS MAY BE AN AREA TO SEE MOST PERISTENT SNOWFALL.
LATE CHANGEOVER TO SNOW OVER THE E WILL FURTHER LIMIT SNOW
ACCUMULATIONS IN THAT AREA SUN NIGHT. NO HEADLINES PERTAINING TO
SNOW ARE WARRANTED AT THIS TIME.
WINDS WILL BE A BIG STORY WITH THE SYSTEM. IN THE WAKE OF THE
DEEPENING SFC LOW...MODELS INDICATE NW WINDS OF 45-55KT AT 850MB
DURING THE PERIOD OF CAA. 4KM HIGH RES NAM SHOWS WIND GUST POTENTIAL
TO A LITTLE OVER 40KT OVER THE KEWEENAW AND TO A LITTLE OVER 50KT
ALONG THE LAKESHORE E OF MARQUETTE. ISALLOBARIC WIND COMPONENT WILL
ADD SOME ENHANCEMENT AS PRES RISES STRENGTHEN OVER THE AREA IN THE
WAKE OF THE DEEPENING LOW. IF ADVY HEADLINES END UP NOT BEING NEEDED
FOR SNOWFALL...WIND HEADLINES WILL BE NEEDED. ON LAKE SUPERIOR...
HIGH GALES ARE LIKELY ON THE E HALF OF LAKE SUPERIOR WITH DECENT
POTENTIAL FOR A PERIOD OF STORM FORCE WINDS LATE OVERNIGHT SUN NIGHT
INTO MON MORNING.
TRANSITION TO PURE LES WILL OCCUR MON/MON NIGHT UNDER NW FLOW AS
850MB TEMPS FALL TO -10/-11C. LINGERING LIGHT LES WILL WIND DOWN/END
OVER WRN UPPER MI MON NIGHT AND OVER NCNTRL UPPER MI TUE MORNING AS
AS FLOW BACKS AND WAA GETS UNDERWAY. WITH SFC HIGH PRES RIDGE
REACHING WRN UPPER MI LATE MON NIGHT...TEMPS COULD PLUMMET IF CLOUDS
CLEAR OUT. NONE OF THE GUIDANCE IS ESPECIALLY COLD. LOWEST GUIDANCE
GENERALLY SUGGEST MINS IN THE UPPER TEENS...AND FCST WILL REFLECT
THESE COLDER NUMBERS.
WAA WED MIGHT YIELD SOME LIGHT PCPN AT THAT TIME. THEN...STRONG
SHORTWAVE MOVING ACROSS SRN CANADA WILL SWEEP ASSOCIATED COLD FRONT
ACROSS THE AREA WED NIGHT...ACCOMPANIED BY SOME -RA/-SN. LES MAY GET
UNDERWAY THU...BUT MODELS HAVE NOT BEEN VERY CONSISTENT ON THE
INTENSITY OF THE COLD FOLLOWING THE FRONT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1223 AM EST SAT NOV 16 2013
EXPECT VFR CONDITIONS OVERNIGHT BEFORE THE ARRIVAL OF GREATER LOW
LEVEL MOISTURE WITH INCREASING SRLY FLOW BRINGS MVFR CIGS INTO THE
AREA SATURDAY MORNING. LLWS WAS MENTIONED AT ALL TAF SITES WITH 40
KNOT WINDS EXPECTED ABOVE A STRENGTHENING INVERSION. THE ONSET OF
IFR CIGS IS EXPETED EARLIEST AT SAW WITH UPSLOPE SRLY FLOW. BY LATE
AFTERNOON AS RAIN ARRIVES INTO THE AREA...CONDITIONS SHOULD ALSO
DROP TO IFR AT CMX/IWD. ALTHOUGH FOG WILL ALSO DEVELOP...RAIN SHOULD
HELP KEEP THE VSBY FROM FALLING BLO 1-2SM SATURDAY EVENING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 521 AM EST SAT NOV 16 2013
SOUTH WINDS WILL INCREASE TO 30KT TODAY AHEAD OF DEEPENING SFC LOW
MOVING FROM THE PLAINS TOWARD THE UPPER MISSISSIPPI VALLEY.
STRONGEST WINDS TODAY/TONIGHT WILL BE OVER EASTERN PORTIONS OF LAKE
SUPERIOR...WHERE THERE MAY BE A FEW GALE GUSTS TO 35KT. STABLE
LOW-LEVEL TEMPERATURE PROFILE AND LACK OF PRESSURE FALLS TO NORTH OF
LAKE SUPERIOR SHOULD LIMIT FREQUENCY OF GUSTS. WINDS WILL DIMINISH
FOR A TIME SUNDAY AS SFC TROF DRIFTS OVERHEAD AND PRES GRADIENT
WEAKENS CONSIDERABLY. NEW LOW PRESSURE ORGANIZING OVER THE PLAINS
WILL THEN LIFT NE ALONG THE TROF AND RAPIDLY DEEPEN AS IT PASSES
ACROSS FAR SE LAKE SUPERIOR INTO NRN ONTARIO. PRES WILL LIKELY FALL
BLO 975MB OR 29.0 INCHES AS IT MOVES N OF THE LAKE SUNDAY NIGHT/MON
MORNING. IN THE NW FLOW IN THE WAKE OF THE DEEPENING LOW PRES...
GALES WILL OCCUR ACROSS ALL BUT FAR WRN LAKE SUPERIOR WITH HIGH END
GALES TO STORM FORCE WINDS LIKELY SUN NIGHT/MON MORNING OVER THE E
HALF. GIVEN STORM POTENTIAL...A STORM WATCH HAS BEEN ISSUED FOR THE
E HALF OF LAKE SUPERIOR. WINDS WILL DIMINISH BELOW 30KT FROM W TO E
MON NIGHT...AND A PERIOD OF LIGHT WINDS UNDER 15KT SHOULD OCCUR TUE
AS HIGH PRES RIDGE PASSES ACROSS LAKE SUPERIOR. S WINDS WILL THEN
RAMP UP TO 20-30KT FOR WED BEHIND THE HIGH AND AHEAD OF THE NEXT
APPROACHING LOW PRES TROF.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
STORM WATCH FROM SUNDAY EVENING THROUGH MONDAY AFTERNOON FOR
LSZ248>251-265>267.
GALE WATCH FROM SUNDAY EVENING THROUGH MONDAY AFTERNOON FOR
LSZ241>245-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...ROLFSON
AVIATION...JLB
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
322 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 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1127 AM CST SAT NOV 16 2013
MPX TAFS STARTING OUT WITH IFR/LIFR CIGS/VSBYS WHICH MAY IMPROVE
SOME DURING THE AFTN WITH MIXING OF -RA...BUT STILL REMAINING BLW 1K.
HOWEVER...NOT UNTIL DRIER AIR ADVECTS FROM THE SW ACROSS IA/NE
WILL WE SEE ANY SIGNIFICANT IMPROVEMENTS. THE WORSE TIME FRAME WILL
OCCUR IN THE FIRST 3 HRS WITH SOME POSSIBILITY OF TSRA AT
KRWF/KEAU DUE TO INCREASING CONVECTION NOTED IN THESE AREAS.
ALTHOUGH KRWF/KRHN/KEAU MAY SEE CIGS LIFT DURING THE EVENING HRS
TO MVFR...NOT TOO OPTIMISTIC UNTIL WINDS SHIFT AND INCREASE FROM
THE SW. LOW CONFIDENCE ON MVFR CIGS DEVELOPING THIS AFTN/EVENING.
AFT 3-6Z...WENT WITH A MORE IFR/LIFR CIGS/VSBYS AT KAXN/KSTC DUE
TO WEAK SFC WINDS AND MIXING IN THE BOUNDARY LAYER...PLUS THE
ADDED MOISTURE FROM -RA/-DZ THIS AFTN. ELSEWHERE...WILL CONTINUE
WITH SOME IMPROVEMENT IN THE EVENING...BUT LOWER THE CIGS ONCE
AGAIN AFT 6Z...THEN INCREASE THE CIGS/VSBYS AFT 12-15Z. WINDS WILL
REMAIN FROM THE S/SE THIS AFTN...THEN MORE S/SW THIS
EVENING...BECOMING MORE W/NW BY SUNDAY MORNING/AFTN.
KMSP...
KEPT THE LOWER CIGS THRU THE AFTN AND EVENING WITH VSBYS LOWERING
TO 2SM IN -RA/-DZ AT TIMES. ALTHOUGH REGIONAL RADAR DOES NOT HAVE
ANYTHING WIDESPREAD...BELIEVE IN THE NEXT HR OR TWO...PRECIPITATION
WILL EXPAND WITH HEAVIER ACTIVITY POSSIBLE 19-21Z WHERE BOTH THE
BEST LIFT AND DEEPER MOISTURE RESIDES. MORE OF A DRIZZLE SCENARIO
AFT 21-22Z...WITH DRIER AIR ADVECTING FROM THE SW THIS EVENING.
KEPT CIGS IFR...BUT MVFR CIGS MAY DEVELOP DURING THE 02-04Z TIME
FRAME. MVFR/VFR CIGS CONTINUE THRU SUNDAY MORNING WITH VFR CONDS
DEVELOPING SUNDAY AFTN AS WINDS INCREASE FROM THE NW. CONFIDENCE
REMAINS HIGH FOR THE CONTINUED IFR CIGS THIS AFTN...CONFIDENCES
LOWERS WITH MVFR CIGS DEVELOPING THIS EVENING/OVERNIGHT.
/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...JLT
AREA FORECAST DISCUSSION
NWS DULUTH MN
308 AM CST SAT NOV 16 2013
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 308 AM CST SAT NOV 16 2013
A WARM SLY FLOW COVERED THE FA AT 08Z WITH A WEAK AREA OF LOW
PRESSURE IN NE ND. A WARM FRONT EXTENDED FROM THE LOW CENTER INTO
THE NORTHERN PART OF THE AREA WHILE A COLD FRONT WAS IN THE EASTERN
DAKOTAS. A MIX OF MID AND HIGH CLOUDS WERE DRIFTING OVER THE WESTERN
GREAT LAKES IN THE WAA AHEAD OF THE LOW. MEANWHILE...UPPER LEVEL
RIDGING WAS IN PLACE AS SEEN IN WATER VAPOR IMAGERY. EXPECT THE
UPPER RIDGE TO MOVE E OF THE AREA THIS MORNING WHILE A TROF DEEPENS
OVER THE LEE OF THE ROCKIES. THIS TROF WILL EJECT A VORT MAX INTO
CENTRAL MN REACHING NW WI BY 18Z. BROUGHT IN SOME SMALL POPS BY 16Z
AND CONTINUE TO SPREAD THEM INTO MUCH OF THE FA BY 18Z IN RESPONSE.
LEFT THE WESTERN EDGE DRY ATTM. LATEST MODELS HAVE BACKED OFF ON THE
POSSIBILITY OF THUNDERSTORMS UNTIL ABOUT 21Z IN NW WI AND HAVE
ADJUSTED ACCORDINGLY. A RUMBLE OF THUNDER MAY BE HEARD AROUND THE
PERIPHERY OF WESTERN LAKE SUPERIOR INTO PINE COUNTY MN. BEST
INSTABILITY APPEARS TO BE OVER THE EASTERN WI PORTION OF THE FA AND
HAVE AN ISOLD MENTION THERE. POPS WILL GRADUALLY INCREASE THROUGH
THE AFTERNOON AS A PARADE OF VORT MAXES LIFT NEWD FROM THE BASE OF
THE UPPER TROF THROUGH 00Z SUNDAY. PCPN WILL BE ALL LIQUID DUE TO
THE WARM ATMOSPHERE IN PLACE.
THE UPPER LEVEL LONG WAVE TROF OVER THE ROCKIES CONTINUES TO DEEPEN
TONIGHT. MORE VORT MAXES WILL CONTINUE TO EJECT OUT AND INTO THE
WESTERN GREAT LAKES. INTERMITTENT BOUTS OF LIGHT RAIN WILL AFFECT
THE FA THROUGH THE NIGHT. THE EXCEPTION WILL BE ALONG THE SOUTHERN
EDGE LATE TONIGHT WHEN A DRY WEDGE MOVES NEARBY. HAVE A FOG MENTION
BEGINNING LATE TONIGHT AS WELL.
THE UPPER TROF FINALLY MOVES OUT OF THE ROCKIES INTO THE MIDWEST
SUNDAY AND BECOMES NEGATIVELY TILTED. A SFC LOW BECOMES ORGANIZED
AHEAD OF THE TROF AND DEEPENS AS IT MOVES FROM SOUTHERN WI INTO
LOWER MI BY 00Z MONDAY. BEHIND THIS LOW...CAA BEGINS OVER THE FA
ALLOWING FOR A MIX OF RAIN AND SNOW IN THE IN THE NW CORNER SUNDAY
MORNING BEFORE CHANGING TO ALL SNOW IN THE AFTERNOON. ONLY A MINOR
ACCUMULATION IS EXPECTED. ALL RAIN IS FORECAST FROM WESTERN LAKE
SUPERIOR TO THE BRAINERD LAKES E INTO NW WI AS THE ATMOSPHERE WILL
BE SLOW TO COOL.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 308 AM CST SAT NOV 16 2013
THE NORTHLAND WILL BE IN THE WAKE OF A PASSING STRONG LOW PRESSURE
SYSTEM WHICH WILL BE MOVING FROM EASTERN ONTARIO TO WESTERN QUEBEC.
COLD AND GUSTY NW FLOW WILL DEVELOP ACROSS THE NORTHLAND SUNDAY
NIGHT. THERE MAY BE LINGERING LIGHT RAIN AND SNOW ACROSS THE
NORTHLAND SUNDAY NIGHT AND MONDAY MORNING...ESPECIALLY ALONG AND
NEAR THE GOGEBIC RANGE IN IRON COUNTY DUE TO THE LAKE ENHANCED AND
LAKE EFFECT SNOW SHOWERS. THE GOGEBIC RANGE COULD SEE UP TO A COUPLE
INCHES OF SNOW.
SEASONABLE TEMPERATURES IN THE UPPER 20S AND LOW 30S MONDAY ARE
EXPECTED MONDAY. THERE SHOULD BE A WARMING TREND FOR THE MIDDLE OF
THE WEEK AS SOUTHERLY WINDS DEVELOP AHEAD OF LOW PRESSURE MOVING
INTO THE WESTERN AND NORTHERN PLAINS. THE WARMING TREND WILL LIKELY
CULMINATE WEDNESDAY WITH HIGHS IN THE UPPER 30S AND LOW 40S. THERE
COULD BE SOME LIGHT RAIN AND SNOW WEDNESDAY THROUGH THURSDAY AHEAD
AND WITH THE PASSAGE OF A COLD FRONT. TEMPERATURES SHOULD BE NEAR
NORMAL FOR THE SECOND HALF OF THE WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1143 PM CST FRI NOV 15 2013
AN AREA OF LOW PRESSURE...WAA AND MOISTURE ADVECTION WILL ALL
COMBINE TO GRADUALLY LOWER CEILINGS THROUGH THE PERIOD TO MAINLY
IFR. THE RAP WAS DOING A DECENT JOB DEPICTING THE MVFR CEILINGS
OVER MO/IL...AND BRINGS THEM NORTH LATE TONIGHT INTO SATURDAY
MORNING AND A LLJ. THERE MAY BE SOME LOW VFR CEILINGS...3500-5000FT...THAT
IMPACT KDLH/KHYR LATE TONIGHT AS WELL. RAIN/DRIZZLE WILL DEVELOP
DURING THE DAY SATURDAY ALONG WITH THE LOWERING CEILINGS. THE RAIN
WILL BE MOST LIKELY OVER EASTERN AREAS OF THE NORTHLAND.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 44 40 44 24 / 70 70 50 30
INL 44 36 38 21 / 10 60 60 40
BRD 47 39 43 23 / 60 40 30 10
HYR 46 42 47 27 / 70 60 60 40
ASX 48 43 47 29 / 80 60 60 70
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...GSF
LONG TERM...GROCHOCINSKI
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS DULUTH MN
1230 AM CST SAT NOV 16 2013
.UPDATE...
ISSUED AT 1227 AM CST SAT NOV 16 2013
REMOVED THE MENTION OF LIGHT RAIN ALONG THE BORDERLAND AS THE RAIN
HAS MOVED INTO CANADA. ALSO REMOVED THE MENTION OF FOG FOR THE
OVERNIGHT AS DEWPOINT DEPRESSIONS ARE LARGE AND THE FOG AT CKC HAS
DISSIPATED. ALSO REMOVED THE MENTION OF DRIZZLE WITH A LACK OF ANY
FORCING NEARBY.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY AFTERNOON)
ISSUED AT 345 PM CST FRI NOV 15 2013
MAIN CONCERNS IN THE SHORT TERM ARE FOCUSED AROUND THE POTENTIAL
FOR PATCHY FOG AND DRIZZLE TONIGHT AND EARLY SATURDAY
MORNING...AND THE RAIN SHOWERS EXPECTED TO DEVELOP TOMORROW MID TO
LATE MORNING FROM SOUTH TO NORTH AND PERSIST THROUGH THE
AFTERNOON. HAVE ALSO ADDED MENTION OF ISOLATED THUNDERSTORMS OVER
PARTS OF NW WISCONSIN IN THE LATE AFTERNOON.
DEEP CYCLONIC FLOW IN PLACE ACROSS MUCH OF THE CENTRAL CONUS TODAY
WITH A COUPLE SHRT WVS RIDING E/NEWD THROUGH THE NRN ROCKIES AND
NRN PLAINS. A SFC LOW IS DEVELOPING ALONG THE FRONT RANGE OF THE
ROCKIES AS A WEAK WARM FRONT EXTENDS EWD THROUGH NE INTO IA. THIS
FRONT WILL LIFT NWD AND COMBINE WITH MODEST WAA/MOISTURE TRANSPORT
FROM THE SOUTH AND A FAST MOVING UPPER S/W TO PRODUCE VERY LIGHT
PRECIP ACROSS THE NORTHLAND. ABOVE 600MB THE ATMOSPHERE WILL
BECOME NEARLY SATURATED. HOWEVER...A FAIRLY DEEP MID-LVL LAYER
WILL REMAIN DRY THROUGH MUCH OF THE NIGHT. AS THE NEAR SFC LAYER
COOLS AND SATURATES...AND SOME OF THE MOISTURE WORKS ITS WAY DOWN
THROUGH THE COLUMN...PATCH DRIZZLE WILL BE POSSIBLE. AT THIS TIME
THE MOST FAVORABLE LOCATION OF PRECIP IS DIFFICULT TO NAIL
DOWN...SO BASICALLY HAVE A BROAD AREA OF PATCHY FOG AND DRIZZLE.
THE SUSTAINED SOUTH WINDS AROUND 5 TO 10 MPH WILL INHIBIT
WIDESPREAD FOG FROM FORMING. HOWEVER...A STRONG INVERSION AND
PLENTY OF MOISTURE IN THE LOW LEVELS WILL BOTH SUPPORT FOG
FORMATION.
THE MAIN AREA OF LOW PRESSURE AT THE SFC WILL EVENTUALLY LIFT TO
THE NE INTO THE DAKOTAS AND SWRN MN DURING THE DAY SATURDAY AND
DRAW UP AN EVEN RICHER SUPPLY OF WARM MOIST AIR FROM THE SOUTH.
THIS AIR MASS WILL ALLOW FOR SLIGHT DESTABILIZATION OVER PARTS OF
NW WI LATE SAT AFTERNOON. HAVE ADDED ISOLATED THUNDERSTORMS FOR
THIS AREA FOR A FEW HOURS. OTHERWISE...PRECIP WILL BE ALL RAIN
WITH AMTS AROUND A QUARTER TO A THIRD OF AN INCH...WITH THE
HIGHEST AMOUNTS ACROSS THE ERN HALF OF THE FORECAST AREA.
TEMPERATURES WILL REMAIN VERY MILD DURING THE NEXT 24 HOURS...WITH
LOWS TONIGHT DROPPING INTO THE MID TO UPPER 30S...AND HIGHS
TOMORROW IN THE 40S.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM CST FRI NOV 15 2013
WIDESPREAD PRECIPITATION WILL CONTINUE INTO SATURDAY NIGHT...BEFORE
GRADUALLY DECREASING FROM SOUTHWEST TO NORTHEAST. THIS WILL HAPPEN
BEFORE A COMPLEX SURFACE LOW DEVELOPS OVER THE REMAINDER OF THE
WEEKEND...WITH PRECIPITATION INCREASING ONCE AGAIN. THE SYSTEM IS
FAIRLY COMPLEX...WITH THE LOW PRESSURE SYSTEM BASICALLY EVOLVING
INTO A MAJOR SURFACE LOW RIGHT OVER OUR REGION. BY LATE SUNDAY... AN
INTENSE SURFACE LOW WILL BE LOCATED OVER THE EASTERN LAKE SUPERIOR
REGION. THE LOW WILL STRENGTHEN EVEN FURTHER ON SUNDAY NIGHT AND
MONDAY...AS IT LIFTS TO NEAR JAMES BAY BY 12Z MONDAY. THE ECMWF HAS
IT DROPPING TO A 975 MB LOW AT THAT TIME. AS THE WEEKEND WEARS
ON...WE WILL BE LOOKING AT SWITCH TO ALL SNOW...AND A DRAMATIC
INCREASE IN WIND. GALES ARE DISTINCTLY POSSIBLE OVER LAKE
SUPERIOR...WITH GUSTY WINDS INLAND AS WELL. DRY HIGH PRESSURE WILL
THEN BUILD INTO THE REGION FROM MONDAY INTO WEDNESDAY...WITH
TEMPERATURES MODERATING CONSIDERABLY BY MIDWEEK. A WEAK LOW PRESSURE
SYSTEM AND UPPER LEVEL SHORTWAVE WILL SET OFF SOME LIGHT
PRECIPITATION FROM WEDNESDAY NIGHT INTO THURSDAY. BY FRIDAY...THERE
IS MAJOR DISAGREEMENT AMONGST THE OPERATIONAL MODEL SET...WITH THE
GFS BRINGING A MAJOR STORM SYSTEM TO THE WESTERN GREAT LAKES. THE
ECMWF ON THE OTHER HAND...BRINGS DRY AND QUIET WEATHER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1143 PM CST FRI NOV 15 2013
AN AREA OF LOW PRESSURE...WAA AND MOISTURE ADVECTION WILL ALL
COMBINE TO GRADUALLY LOWER CEILINGS THROUGH THE PERIOD TO MAINLY
IFR. THE RAP WAS DOING A DECENT JOB DEPICTING THE MVFR CEILINGS
OVER MO/IL...AND BRINGS THEM NORTH LATE TONIGHT INTO SATURDAY
MORNING AND A LLJ. THERE MAY BE SOME LOW VFR CEILINGS...3500-5000FT...THAT
IMPACT KDLH/KHYR LATE TONIGHT AS WELL. RAIN/DRIZZLE WILL DEVELOP
DURING THE DAY SATURDAY ALONG WITH THE LOWERING CEILINGS. THE RAIN
WILL BE MOST LIKELY OVER EASTERN AREAS OF THE NORTHLAND.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 44 40 43 23 / 60 60 60 40
INL 43 36 38 21 / 30 70 60 40
BRD 47 38 42 23 / 50 30 40 20
HYR 45 43 47 26 / 70 60 70 40
ASX 47 43 47 28 / 70 60 70 60
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
UPDATE...GSF
SHORT TERM...BJT
LONG TERM...DAP
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS DULUTH MN
1143 PM CST FRI NOV 15 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY AFTERNOON)
ISSUED AT 345 PM CST FRI NOV 15 2013
MAIN CONCERNS IN THE SHORT TERM ARE FOCUSED AROUND THE POTENTIAL
FOR PATCHY FOG AND DRIZZLE TONIGHT AND EARLY SATURDAY
MORNING...AND THE RAIN SHOWERS EXPECTED TO DEVELOP TOMORROW MID TO
LATE MORNING FROM SOUTH TO NORTH AND PERSIST THROUGH THE
AFTERNOON. HAVE ALSO ADDED MENTION OF ISOLATED THUNDERSTORMS OVER
PARTS OF NW WISCONSIN IN THE LATE AFTERNOON.
DEEP CYCLONIC FLOW IN PLACE ACROSS MUCH OF THE CENTRAL CONUS TODAY
WITH A COUPLE SHRT WVS RIDING E/NEWD THROUGH THE NRN ROCKIES AND
NRN PLAINS. A SFC LOW IS DEVELOPING ALONG THE FRONT RANGE OF THE
ROCKIES AS A WEAK WARM FRONT EXTENDS EWD THROUGH NE INTO IA. THIS
FRONT WILL LIFT NWD AND COMBINE WITH MODEST WAA/MOISTURE TRANSPORT
FROM THE SOUTH AND A FAST MOVING UPPER S/W TO PRODUCE VERY LIGHT
PRECIP ACROSS THE NORTHLAND. ABOVE 600MB THE ATMOSPHERE WILL
BECOME NEARLY SATURATED. HOWEVER...A FAIRLY DEEP MID-LVL LAYER
WILL REMAIN DRY THROUGH MUCH OF THE NIGHT. AS THE NEAR SFC LAYER
COOLS AND SATURATES...AND SOME OF THE MOISTURE WORKS ITS WAY DOWN
THROUGH THE COLUMN...PATCH DRIZZLE WILL BE POSSIBLE. AT THIS TIME
THE MOST FAVORABLE LOCATION OF PRECIP IS DIFFICULT TO NAIL
DOWN...SO BASICALLY HAVE A BROAD AREA OF PATCHY FOG AND DRIZZLE.
THE SUSTAINED SOUTH WINDS AROUND 5 TO 10 MPH WILL INHIBIT
WIDESPREAD FOG FROM FORMING. HOWEVER...A STRONG INVERSION AND
PLENTY OF MOISTURE IN THE LOW LEVELS WILL BOTH SUPPORT FOG
FORMATION.
THE MAIN AREA OF LOW PRESSURE AT THE SFC WILL EVENTUALLY LIFT TO
THE NE INTO THE DAKOTAS AND SWRN MN DURING THE DAY SATURDAY AND
DRAW UP AN EVEN RICHER SUPPLY OF WARM MOIST AIR FROM THE SOUTH.
THIS AIR MASS WILL ALLOW FOR SLIGHT DESTABILIZATION OVER PARTS OF
NW WI LATE SAT AFTERNOON. HAVE ADDED ISOLATED THUNDERSTORMS FOR
THIS AREA FOR A FEW HOURS. OTHERWISE...PRECIP WILL BE ALL RAIN
WITH AMTS AROUND A QUARTER TO A THIRD OF AN INCH...WITH THE
HIGHEST AMOUNTS ACROSS THE ERN HALF OF THE FORECAST AREA.
TEMPERATURES WILL REMAIN VERY MILD DURING THE NEXT 24 HOURS...WITH
LOWS TONIGHT DROPPING INTO THE MID TO UPPER 30S...AND HIGHS
TOMORROW IN THE 40S.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM CST FRI NOV 15 2013
WIDESPREAD PRECIPITATION WILL CONTINUE INTO SATURDAY NIGHT...BEFORE
GRADUALLY DECREASING FROM SOUTHWEST TO NORTHEAST. THIS WILL HAPPEN
BEFORE A COMPLEX SURFACE LOW DEVELOPS OVER THE REMAINDER OF THE
WEEKEND...WITH PRECIPITATION INCREASING ONCE AGAIN. THE SYSTEM IS
FAIRLY COMPLEX...WITH THE LOW PRESSURE SYSTEM BASICALLY EVOLVING
INTO A MAJOR SURFACE LOW RIGHT OVER OUR REGION. BY LATE SUNDAY... AN
INTENSE SURFACE LOW WILL BE LOCATED OVER THE EASTERN LAKE SUPERIOR
REGION. THE LOW WILL STRENGTHEN EVEN FURTHER ON SUNDAY NIGHT AND
MONDAY...AS IT LIFTS TO NEAR JAMES BAY BY 12Z MONDAY. THE ECMWF HAS
IT DROPPING TO A 975 MB LOW AT THAT TIME. AS THE WEEKEND WEARS
ON...WE WILL BE LOOKING AT SWITCH TO ALL SNOW...AND A DRAMATIC
INCREASE IN WIND. GALES ARE DISTINCTLY POSSIBLE OVER LAKE
SUPERIOR...WITH GUSTY WINDS INLAND AS WELL. DRY HIGH PRESSURE WILL
THEN BUILD INTO THE REGION FROM MONDAY INTO WEDNESDAY...WITH
TEMPERATURES MODERATING CONSIDERABLY BY MIDWEEK. A WEAK LOW PRESSURE
SYSTEM AND UPPER LEVEL SHORTWAVE WILL SET OFF SOME LIGHT
PRECIPITATION FROM WEDNESDAY NIGHT INTO THURSDAY. BY FRIDAY...THERE
IS MAJOR DISAGREEMENT AMONGST THE OPERATIONAL MODEL SET...WITH THE
GFS BRINGING A MAJOR STORM SYSTEM TO THE WESTERN GREAT LAKES. THE
ECMWF ON THE OTHER HAND...BRINGS DRY AND QUIET WEATHER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1143 PM CST FRI NOV 15 2013
AN AREA OF LOW PRESSURE...WAA AND MOISTURE ADVECTION WILL ALL
COMBINE TO GRADUALLY LOWER CEILINGS THROUGH THE PERIOD TO MAINLY
IFR. THE RAP WAS DOING A DECENT JOB DEPICTING THE MVFR CEILINGS
OVER MO/IL...AND BRINGS THEM NORTH LATE TONIGHT INTO SATURDAY
MORNING AND A LLJ. THERE MAY BE SOME LOW VFR CEILINGS...3500-5000FT...THAT
IMPACT KDLH/KHYR LATE TONIGHT AS WELL. RAIN/DRIZZLE WILL DEVELOP
DURING THE DAY SATURDAY ALONG WITH THE LOWERING CEILINGS. THE RAIN
WILL BE MOST LIKELY OVER EASTERN AREAS OF THE NORTHLAND.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 39 44 40 43 / 10 60 60 60
INL 37 43 36 38 / 30 30 70 60
BRD 38 47 38 42 / 10 50 30 40
HYR 39 45 43 47 / 10 70 60 70
ASX 41 47 43 47 / 10 70 60 70
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...BJT
LONG TERM...DAP
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS GLASGOW MT
349 PM MST SAT NOV 16 2013
.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH MONDAY...
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...
VFR CONDITIONS ARE EXPECTED THROUGH THE AFTERNOON FOR ALL
TERMINALS. 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
&&
.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 BINGHAMTON NY
821 PM EST SUN NOV 17 2013
.SYNOPSIS...
A LARGE STORM SYSTEM WILL STRENGTHEN OVER THE GREAT LAKES AND
BLAST A COLD FRONT THROUGH OUR REGION BETWEEN MIDNIGHT AND DAWN
TONIGHT. THE FRONT WILL BE ACCOMPANIED BY A GUSTY LINE OF SHOWERS
AND ISOLATED THUNDERSTORMS. LOCALIZED DAMAGING WINDS WILL BE POSSIBLE.
COLDER AIR WILL MOVE IN BEHIND THE FRONT...WITH GUSTY WINDS
CONTINUING MONDAY. SOME LAKE EFFECT SNOW SHOWERS CAN BE EXPECTED
MONDAY NIGHT INTO TUESDAY MORNING IN CENTRAL NEW YORK.
&&
.NEAR TERM /THROUGH MONDAY/...
815 PM UPDATE...
982MB LOW IS CURRENTLY IN VICINITY OF EXTREME EASTERN UP OF
MICHIGAN. CDFNT EXTNDS TWD THE SOUTH ACROSS CNTRL LWR MICHIGAN AND
THRU WRN OHIO WITH WINDS GUSTING ANYWHERE BTWN 35-50KTS.
CONVECTIVE LINE HAS MADE IT INTO NE OH, HWVR CLD-GROUND LIGHTNING
IS ALMOST NON-EXISTENT WITH THE LINE WITH THE MAIN LIGHTNING
STRIKES OVR ONTARIO AND SRN KY. IN-CLOUD LIGHTNING IS NOT MUCH
BETTER AS JUST A FEW STRIKES EXIST OVR ERN OHIO. 00Z KBUF RAOB
SHOWING MINIMAL CAPES AND POOR LAPSE RATES AT THIS TIME AND ONLY
EXPECT THAT TO CONTINUE AS THE LINE HEADS EAST PER KALY SNDG.
LATEST HRRR CONTINUES TO SUGGEST A VRY THIN CONVECTIVE LINE MVG
THRU BTWN 05Z-09Z, PLACING THE LINE ALONG THE I-81 CORRIDOR BY
07Z. ALL INDICATIONS ARE THAT THIS TIMING LOOKS TO BE RIGHT ON
TARGET. THUNDER THREAT LOOKS ISOLD AT BEST BUT STILL EXPECT A VRY
BRIEF WINDOW OF STRONG WINDS ALONG THE FRONT. THUS, WIND ADVISORY
WL CONTINUE AS IS. WL HANDLE ANY DAMAGING WINDS WITH AN SPS OR
SHORT-FUSED HIGH WIND WRNG.
SEE NO REASON TO CHG HRLY T/TD VALUES AS THEY WL SLOWLY RISE
OVRNGT BFR FROPA. NO CHGS NEEDED TO THESE GRIDS ATTM.
PREV DISCO BLO...
115 PM UPDATE... MAIN CONCERN IS FOR STRONG COLD FRONT MOVING
THROUGH LATE TONIGHT WITH GUSTY WINDS...AND A POTENTIAL SQUALL
THAT COULD HAVE LOCALIZED DAMAGING GUSTS.
WELL AHEAD OF THE FRONT...STOUT SOUTHWEST FLOW IS RIDDLED WITH
SHORTWAVES WHICH HAVE ALREADY PRODUCED SOME SHOWERS OVER THE TWIN
TIERS THROUGH CENTRAL NY. SHOWERS ARE PRESSING SOUTHEAST WITH
TIME YET ALSO WITH SATURATED LAYER NOT AS DEEP SO IS BECOMING MORE
SPOTTY IN COVERAGE. ALL OF THIS OF COURSE TAKES A BACK SEAT TO THE
SET UP FOR TONIGHT.
SYNOPTICALLY SPEAKING...STRONG 850MB JET OCCURS AHEAD OF AND ALONG
FRONT OF 60-75 KTS. COMPARED TO THE WAY THE MODELS LOOKED 24 HRS
AGO...THE JET WHILE STILL STRONG IS NOT POSITIONED QUITE AS LOW
IN THE COLUMN. ALSO...MODEL SOUNDINGS ALL SUGGEST NEAR SURFACE AIR
WILL NOT BE CONDUCIVE FOR MIXING DOWN STRONG GUSTS. UNTIL THE
FRONT COMES...HIGHEST GUSTS WILL BE LIMITED MAINLY TO RIDGETOPS IN
CENTRAL NY. IN COORDINATION WITH ADJOINING NWS OFFICES I HAVE
ELECTED TO REPLACE THE HIGH WIND WATCH WITH A WIND ADVISORY /PLUS
A FEW MORE ZONES/...GIVEN EXPECTATION THAT PEAK GUSTS STAYING
BELOW 50 MPH. ANYTHING HIGHER SHOULD BE LIMITED TO THE POTENTIAL
SQUALL IMMEDIATELY ALONG THE FRONT ITSELF...AS HINTED AT BY SPC
SLIGHT RISK FOR SEVERE THUNDERSTORMS FOR OUR WHOLE AREA. THIS
SHORT-FUSE POSSIBILITY WILL BE HANDLED VIA SPS/SVR IF NECESSARY.
CONFIDENCE HAS INCREASED ON TIMING OF FRONT OVERNIGHT...WITH
SQUALL PASSING THROUGH DURING 05Z-10Z TIME FRAME. LOW TOPPED LINE
EXPECTED WITH LIMITED IF ANY LIGHTNING...BUT CONVECTIVE
NONETHELESS AND CAPABLE OF MIXING DOWN STRONG GUSTS. CONDITIONS
MORE FAVORABLE UPSTREAM...BUT STRONGLY FORCED FRONT WILL STILL
CARRY EAST FROM THERE WITH GOOD GUSTS...THE ONLY QUESTION IS HOW
STRONG. 925-850MB JET WILL BE DECREASING JUST AS FRONT CARRIES
THROUGH THE REGION. ALL-IN-ALL AN EERIE WARM EVENING FOLLOWED BY
AN ACTIVE PERIOD MIDNIGHT ONWARD. FORECAST DETAILS HAVE BEEN
UPDATED TODAY THROUGH TONIGHT...INCLUDING SPECIFIC TIMING FOR
CONVECTIVE LINE...AND QUIRKY VERY MILD NON-DIURNAL TEMPERATURES.
POST-FRONTAL ENVIRONMENT MONDAY WILL CONTINUE TO FEATURE GUSTY
WINDS...THIS TIME JUST FROM PRESSURE GRADIENT. ADVISORY LEVEL
GUSTS STILL PROBABLE FOR MUCH OF CENTRAL NY AND PERHAPS HIGHER
ELEVATIONS OF TWIN TIERS/CATSKILLS. FARTHER SOUTHEAST...25 TO 35
MPH GUSTS. WITH WINDS FROM 250-ISH DIRECTION AND 850MB
TEMPERATURES ONLY DIPPING TO ZERO AND FIVE BELOW CELSIUS BY LATE
MONDAY AFTERNOON...AT LEAST FOR DURING THE DAY I AM ONLY EXPECTING
SPOTTY RAIN SHOWERS REACHING INTO CENTRAL SOUTHERN TIER FROM LAKE
ERIE...AND RAIN SHOWERS DEVELOPING NORTH OF THE NY THRUWAY FROM
LAKE ONTARIO.
NON-DIURNAL TEMPERATURES THROUGH THE PERIOD...INCLUDING VERY MILD
CONDITIONS TONIGHT AND THEN STEADY OR FALLING ON MONDAY DUE TO
STRONG COLD AIR ADVECTION.
&&
.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
SOME LAKE EFFECT
PRECIPITATION WILL LIKELY BE OCCURRING SOUTHEAST LAKE ONTARIO
MONDAY NIGHT. 850 MB TEMPERATURES START OUT AROUND -5 C EARLY IN
THE EVENING AND FALL TO -8 TO -10 BY TUESDAY MORNING. PRECIPITATION
EARLY TUESDAY EVENING WILL LIKELY BE A MIX OF RAIN AND SNOW
SHOWERS EAST OF LAKE ONTARIO... TRENDING TOWARD SNOW OVERNIGHT. BOUNDARY
TEMPERATURES WILL BE MARGINAL FOR ACCUMULATIONS... ESPECIALLY AT
LOWER ELEVATIONS. THE FLOW WILL BE FROM AROUND 290 EARLY IN THE
NIGHT SHIFTING TO AROUND 310 BY TUESDAY MORNING. BASED ON THIS
HAVE GONE WITH LIKELY POPS ACROSS OUR NORTHERN COUNTIES MONDAY
EVENING... THEN CHC POPS SPREADING SOUTH TOWARD THE SOUTHERN TIER OF
NY OVERNIGHT. WITH TEMPERATURES MARGINALLY COLD ENOUGH FOR SNOW
AND SHIFTING WINDS AM NOT EXPECTING A MAJOR EVENT... BUT SOME
SMALL ACCUMULATIONS COULD OCCUR ESPECIALLY AT ELEVATIONS ABOVE
1000 FEET ABOVE SEA LEVEL.
SCATTERED LIGHT SNOW SHOWERS MAY CONTINUE INTO TUESDAY MORNING
WITH A 310-320 FLOW FAVORING AREAS DOWNSTREAM OF THE FINGER
LAKES... HOWEVER WITH TEMPERATURES ONLY MARGINALLY COLD ENOUGH FOR
LAKE EFFECT SNOW AND MOISTURE RAPIDLY DECREASING EXPECT ONLY
MINOR IF ANY ACCUMULATIONS ON TUESDAY. HIGH PRESSURE WIL BUILD ACROSS THE
AREA BRINGING DRY SEASONABLY COOL WEATHER TUESDAY NIGHT INTO
WEDNESDAY.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
GFS AND ECMWF ARE IN GENERALLY GOOD AGREEMENT ON THE EVOLUTION OF
THE PATTERN LATE NEXT WEEK ALTHOUGH WITH THE USUAL TIMING AND
INTENSITY DIFFERENCES THAT ARE OFTEN SEEN AT THAT TIME RANGE.
THURSDAY SHOULD BE DRY AND MILD WITH HIGH PRESSURE MOVING OFF THE EAST
COAST. CHANCE OF SHOWERS WILL INCREASE FRIDAY AND SATURDAY AS THE
NEXT COLD FRONT APPROACHES FROM THE WEST. BEST CHANCE FOR
PRECIPITATION APPEARS TO BE SATURDAY AS A COLD FRONT MOVES ACROSS
THE AREA. AT THIS POINT THE MOST LIKELY P-TYPE WITH THIS SYSTEM
APPEARS TO BE RAIN BUT SOME MIX MAY OCCUR IF SOME OF THE COOLER
LONG-RANGE SOLUTIONS WERE TO VERIFY. COLD WEATHER WILL RETURN ON
SUNDAY WITH BOTH THE GFS AND ECMWF ADVERTISING THE COLDEST WEATHER
OF THE SEASON BY EARLY NEXT WEEK.
&&
.AVIATION /01Z MONDAY THROUGH FRIDAY/...
A COLD FRONT APPROACHING FROM THE WEST WILL BRING RAIN SHOWERS
ACCOMPANIED BY GUSTY WINDS TO THE TERMINALS BETWEEN 5Z AND 9Z.
BRIEF LOW MVFR TO BORDERLINE IFR CONDITIONS ARE POSSIBLE IN THE
DOWNPOURS. THE BGM TERMINAL WILL LIKELY REMAIN AT A CEILING OF 500
TO 900 FEET DUE TO ELEVATION EFFECTS.
COOLER AND DRIER AIR WILL FILTER IN BEHIND THE FRONT OVERNIGHT,
ALLOWING MAINLY MVFR CEILINGS TO BREAK UP AND RISE. AT THIS
POINT...DOWNWARD MOTION IN THE ATMOSPHERE WILL KICK UP WIND SPEEDS
AND KEEP SUSTAINED WINDS OF 20 TO 25 KNOTS OVER THE TERMINALS FOR
MUCH OF MONDAY.
OUTLOOK...
MON AFTN THRU TUE MRNG...MVFR POSSIBLE IN SNOW SHOWERS...MAINLY SYR
AND RME MON NGT AND PERHAPS ALSO KITH-KBGM TUE MRNG.
WED/THU...VFR.
FRI...POSSIBLE RESTRICTIONS FROM -SHRA.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WIND ADVISORY UNTIL 4 PM EST MONDAY FOR PAZ038.
NY...WIND ADVISORY UNTIL 4 PM EST MONDAY FOR NYZ009-015>018-022>025-
036-037-044>046-055-056.
&&
$$
SYNOPSIS...MDP/PVN
NEAR TERM...MDP/PVN
SHORT TERM...MSE
LONG TERM...MDP/MSE
AVIATION...DJP
AREA FORECAST DISCUSSION
NWS RALEIGH NC
940 AM EST SAT NOV 16 2013
.SYNOPSIS...
WEAK HIGH PRESSURE WILL EXTEND ACROSS CENTRAL NC TODAY THEN DRIFT
EAST TONIGHT AND SUNDAY. A STRONG COLD FRONT WILL APPROACH FROM THE
WEST SUNDAY AND CROSS OUR AREA SUNDAY NIGHT THROUGH EARLY MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 940 AM SATURDAY...
REST OF TODAY: AS THE PREVIOUS SHIFT NOTED... THE BIGGEST CHALLENGE
TODAY IS THE EXTENT OF CLOUD COVER AND ITS EFFECTS ON TEMPS. THE 12Z
GSO SOUNDING SHOWED DEEP NEAR-SATURATION EXTENDING UP TO 650 MB...
AND AREA PILOT REPORTS THIS MORNING INDICATE CLOUD DEPTHS UP TO 3K
FT. TRIAD FORECAST SOUNDINGS FROM RECENT RAP MODEL RUNS DID NOT
DEPICT THE CLOUD DEPTH WELL (LITTLE TOO DRY ABOVE 850 MB)...
ALTHOUGH THE UPSTREAM 12Z FFC SOUNDING DOES SUGGEST WE`LL SEE SOME
DRYING ALOFT (ABOVE 900 MB) THROUGH THE DAY. THE VERY LIGHT
NEAR-SURFACE WINDS ALONG WITH THE STABILITY OF THE LOWEST 50-100 MB
WILL LIMIT VERTICAL AND HORIZONTAL MIXING HOWEVER WITH THIS AIR MASS
BANKED UP AGAINST THE HIGHER TERRAIN... AND EXPECT THAT THESE CLOUDS
WILL HOLD FIRM FOR MUCH OF THE DAY ACROSS OUR WRN CWA. THE LIGHTER
WINDS IN THE ERN CWA WILL DISCOURAGE MIXING EVEN MORE... AND A
RECENT AMDAR AIRCRAFT SOUNDING FROM RDU SHOWS THE MOIST LAYER
STRETCHING UP TO 750 MB... SO THE FEW BREAKS AND THIN SPOTS
CURRENTLY OVER THE CENTRAL/ERN PIEDMONT MAY BE THE PEAK OF SUNSHINE
UNTIL LATER THIS AFTERNOON (AFTER 3 PM). ALL OF THIS SHOULD PUT A
DAMPER ON TEMPS... AND BASED ON THE LATEST READINGS... WE MAY ONLY
SEE READINGS CLIMB ANOTHER 10 OR SO DEGREES THROUGH THE DAY. WILL
NUDGE HIGHS SLIGHT DOWNWARD IN THE WEST AND UPWARD IN THE EAST AND
SOUTH (WHICH IS SEEING THE MOST SUNSHINE THIS MORNING). HIGHS 62 NW
TO 72 EAST. -GIH
TONIGHT...LIGHT/NEAR CALM WIND REGIME AND PLENTY OF MOISTURE IN THE
LOWEST 5K-8K FT SUGGEST A RETURN OF LOW OVERCAST WITH THE POTENTIAL
FOR AREAS OF FOG. COULD SEE SOME DRIZZLE THEN ISENTROPIC LIFT
MARGINAL AT BEST. THE MODIFYING AIR MASS AND EXTENSIVE CLOUD COVER
WILL MAINTAIN RELATIVELY MILD OVERNIGHT TEMPS FOR THIS TIME OF YEAR.
MIN TEMPS GENERALLY IN THE LOWER 50S. -WSS
&&
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 315 AM SATURDAY...
SUNDAY...S/W RIDGE EXITS OUR REGION EARLY SUNDAY. THIS WILL ALLOW A
S/W IN THE NORTHERN STREAM TO PROGRESS E-NE FROM THE
CENTRAL-NORTHERN PLAINS INTO THE WESTERN LAKES BY EARLY SUNDAY
EVENING. THE SFC COLD FRONT ATTENDANT WITH THE S/W SHOULD STRETCH
FROM LAKE MICHIGAN SSW TO NEAR MEMPHIS. THE APPROACH OF THIS FRONTAL
SYSTEM WILL INDUCE AND STRENGTHEN A SLY FLOW ACROSS CENTRAL NC BY
SUNDAY AFTERNOON. WHILE CLOUDINESS WILL BE QUITE EXTENSIVE...THE
WARM SLY FLOW SHOULD BOOST TEMPS INTO THE 70-75 DEGREE RANGE. IF A
FEW RENEGADE SHOWERS WERE TO OCCUR SUNDAY AFTERNOON ACROSS THE
WEST...THESE SHOWERS MAY KNOCK TEMPS DOWN A FEW DEGREES. OTHERWISE
RAIN CHANCES THROUGH SUNSET APPEAR MINIMAL.
SUNDAY NIGHT...ATMOSPHERE WILL BE CHARACTERIZED AS A HIGH SHEAR/LOW
CAPE ENVIRONMENT AS A STRENGTHENING LOW LEVEL JET WILL CROSS OUR
REGION OVERNIGHT. THIS WILL RESULT IN BULK SHEAR VALUES INT HE
35-50KT RANGE...SUPPORTIVE OF ORGANIZED CONVECTION. CURRENTLY MODEL
INSTABILITY LACKING WITH MUCAPE VALUES NO WORSE THAN 250-300 J/KG
EXPECTED. REVIEW OF GFS BUFKIT SOUNDING DEPICT A RATHER EXTENSIVE
WARM LAYER IN THE 850-700MB LAYER. MID LEVEL LAPSE RATES APPEAR TO
BE NO WORSE THAN 5.5 DEG C/KM. DO WONDER IF MODEL INSTABILITY MAY BE
UNDERDONE AS SFC DEWPOINTS HAVE THE POTENTIAL TO RECOVER INTO THE
LOW-MID 60S OVER MOST OF CENTRAL NC. THUS CANNOT TOTALLY RULE OUT
THE POSSIBILITY OF A STRONG OR SEVERE STORMS OVERNIGHT SUNDAY NIGHT.
HOWEVER...SUCH OCCURRENCE APPEARS TO BE VERY LIMITED AT THIS TIME SO
REFRAIN FROM MENTIONING THUNDER AT THIS TIME AND AWAIT LATER MODEL
GUIDANCE/UPDATES. APPEARS TO BE FAIRLY DEEP LIFT WITH THE FRONT AND
MOISTURE PLENTIFUL. HAVE INCREASES POPS TO LIKELY OR LOW END
CATEGORICAL ACROSS THE REGION SUNDAY AS TH SFC FRONT SHOULD BE ON
OUR WESTERN PERIPHERY PRIOR TO DAYBREAK MONDAY. VERY MILD SUNDAY
NIGHT WITH MIN TEMPS NEAR 60 NW TO LOW-MID 60S ELSEWHERE.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 315 AM SATURDAY...
MONDAY AND MONDAY NIGHT:
THE SURFACE COLD FRONT MENTIONED IN THE SHORT TERM IS EXPECTED TO
CROSS CENTRAL NC MONDAY MORNING INTO THE EARLY AFTERNOON... WITH THE
BEST CHANCE FOR SHOWERS... AND PERHAPS EVEN A FEW STORMS... IN
ADVANCE OF THE FRONT. FOR NOW... WILL SHOW THE HIGHEST POPS ACROSS
EASTERN AND SOUTHEASTERN PORTIONS OF THE AREA FOR THE MORNING
(SLIGHT CHANCE NW TO LIKELY E/SE)... WITH ONLY A LINGERING CHANCE IN
OUR FAR EAST/SOUTHEAST BY AFTERNOON. THE MAIN DYNAMICS ARE EXPECTED
TO PASS WELL TO THE NORTH OF THE AREA. GIVEN THIS AND THE TIME OF
DAY (MORNING) ALONG WITH THE GOOD LOW LEVEL JET PROGGED TO BE TO THE
EAST OF CENTRAL NC BY 12Z MONDAY... WE DO NOT ANTICIPATE ANY SEVERE
WEATHER. THE GOOD PUSH OF COLD AIR IS EXPECTED TO LAG THE FRONT
THOUGH... WITH DOWNSLOPE FLOW ON MONDAY. GIVEN THE DOWNSLOPE FLOW
AND QUICKLY CLEARING SKIES BEHIND THE FRONT... ALONG WITH TEMPS
STARTING OUT GENERALLY IN THE 60S ACROSS THE AREA... EXPECT HIGH
TEMPS WILL BE AROUND 70 NORTHWEST TO THE MID 70S... MAYBE EVEN UPPER
70S... SOUTHEAST.
HIGH PRESSURE WILL BUILD INTO THE AREA ON MONDAY NIGHT WITH LOW
TEMPS DRIVEN BY CAA. LOWS ON TUESDAY MORNING ARE EXPECTED TO RANGE
FROM THE UPPER 30S NORTH TO LOWER 40S SOUTH... WITH A NORTHWESTERLY
TO NORTHERLY WIND.
TUESDAY THROUGH FRIDAY:
SURFACE HIGH PRESSURE CENTERED ACROSS THE OHIO VALLEY/GREAT LAKES
REGION START THE PERIOD IS EXPECTED TO MOVE EASTWARD AND OFF THE
NORTHEAST/NEW ENGLAND COAST BY THURSDAY... WHILE EXTENDING SOUTHWARD
INTO CENTRAL NC. A LOW AMPLITUDE FLOW ALOFT WILL PERSIST ACROSS THE
REGION GENERALLY THROUGH THE REMAINDER OF THE FORECAST PERIOD...
ALTHOUGH HEIGHTS ALOFT WILL SLOWLY RISE THROUGH THIS TIMEFRAME.
MEDIUM RANGE MODELS ARE STRUGGLING HOW TO HANDEL THE EVOLUTION OF
THE LARGE SCALE FLOW PATTERN THOUGH... AT THE END OF THE FORECAST
PERIOD. NEAR THE END OF THE PERIOD MEDIUM RANGE MODELS BEGIN TO
TREND TO AN ERN PAC/WEST COAST RIDGE AND DOWNSTREAM TROUGHING
PATTERN. FOR NOW IT APPEARS THAT ANY SYSTEM ASSOCIATED WITH THIS
NEXT APPROACHING TROUGH WILL HOLD OFF UNTIL BEYOND THE MEDIUM RANGE.
THUS... FOR US WE SHOULD SEE DRY CONDITIONS FOR THE REMAINDER OF THE
WEEK WITH SLOWLY MODERATING TEMPS. HOWEVER... SKIES WILL BE SUNNY TO
START THE PERIOD... THEN TRANSITION TO PARTLY TO MOSTLY CLOUDY WITH
BOTH INCREASING HIGH LEVEL MOISTURE LATE WEEK FROM THE WEST ALONG
WITH EASTERLY FLOW ADVECTING IN MOISTURE OFF THE ATLANTIC ON
THURSDAY INTO FRIDAY AS THE SURFACE HIGH SHIFTS OFFSHORE. HIGH TEMPS
GENERALLY BE IN THE 50S... WITH LOWS RANGING FROM GENERALLY 30 TO 40
DEGREES... COLDEST ON WEDNESDAY MORNING (WHERE A FEW UPPER 20S CANT
BE RULED OUT).
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
AS OF 645 AM SATURDAY...
WIDESPREAD LOW END MVFR/IFR CEILINGS ACROSS CENTRAL NC WITH POCKETS
OF MVFR VISIBILITY DUE TO FOG WILL PERSIST ACROSS CENTRAL NC UNTIL
14Z. AFTER WHICH...VISIBILITIES WILL IMPROVE TO GREATER THAN 6 MILES
AND CEILINGS WILL GRADUALLY LIFT THOUGH REMAIN IN THE MVFR RANGE
UNTIL 18Z-20Z. BY MID AFTERNOON...EXPECT CEILINGS TO CONTINUE TO
LIFT AND EVENTUALLY SCATTER AT MOST SPOTS WITH CLOUD BASES
3000-4000FT.
THE LOWER LAYERS OF THE ATMOSPHERE WILL REMAIN MOIST LATE TODAY
THROUGH TONIGHT. WITH LITTLE MIXING ANTICIPATED...EXPECT CEILINGS TO
LOWER SHORTLY AFTER SUNSET WITH WIDESPREAD LOW END MVFR/IFR
CEILINGS ANTICIPATED THIS EVENING AND PERSISTING INTO SUNDAY
MORNING. AGAIN...EXPECT A GRADUAL IMPROVEMENT IN CEILINGS LATE
SUNDAY MORNING INTO SUNDAY AFTERNOON. AN APPROACHING COLD FRONT WILL
INCREASE THE THREAT FOR SHOWERS AND ASSOCIATED MVFR
VISIBILITIES...ESPECIALLY SUNDAY NIGHT THROUGH EARLY MONDAY.
SOUTHERLY SFC WINDS WILL BECOME BREEZY AHEAD OF THE FRONT LATE
SUNDAY INTO SUNDAY NIGHT WITH SUSTAINED WINDS 10-15KTS AND GUST
20-25KTS PROBABLE SUNDAY NIGHT.
THE COLD FRONT WILL SWEEP THROUGH CENTRAL NC MONDAY MORNING. BEHIND
THE FRONT...MUCH DRIER AIR WILL QUICKLY DIMINISH THE SHOWERS AND
DISSIPATE THE CLOUD COVERAGE. VFR CONDITIONS SHOULD COVER CENTRAL NC
MONDAY AFTERNOON AND PERSIST THROUGH WEDNESDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...HARTFIELD/WSS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1226 AM EST SAT NOV 16 2013
.SYNOPSIS...
A WARM FRONT AND COASTAL TROUGH WILL BRING SHOWERS OVERNIGHT.
ABOVE NORMAL TEMPERATURES ARE EXPECTED THROUGH THE WEEKEND WITH
THE RISK FOR SHOWERS INCREASING AGAIN LATE SUNDAY INTO MONDAY AS A
COLD FRONT APPROACHES FROM THE WEST. THE FRONT WILL CROSS THE AREA
MONDAY AFTERNOON...FOLLOWED BY DRIER AND COOLER CONDITIONS THROUGH
MUCH OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 12:30 AM SATURDAY...NO CHANGES TO THE FORECAST WITH THE
LATEST UPDATE. PREVIOUS DISCUSSION FOLLOWS:
I`VE GOT TO SAY...THIS FORECAST ISN`T WORKING OUT LIKE I HAD
HOPED. THE 00Z CHARLESTON SOUNDING SHOWS PRECIPITABLE WATER HAS
RISEN TO NEARLY 1.3 INCHES...BUT ALSO SHOWS SEVERAL 3000-5000 FT
THICK DRY LAYERS LOCATED RIGHT IN THE ZONE I WOULD EXPECT THE BEST
ISENTROPIC LIFT TO BE OCCURRING. THE 00Z NAM INITIALIZED QUITE
WELL VERSUS THE CHARLESTON THERMAL/MOISTURE PROFILE AND HAS REALLY
TONED DOWN ITS RAINFALL POTENTIAL THROUGH 12Z. THE 18Z GFS WAS FAR
TOO WET AND SHOWS TOO MUCH MOISTURE THROUGHOUT THE 700-400 MB
LAYER VERSUS THE CHARLESTON SOUNDING. THE LATEST HRRR ALSO IS NOT
CAPTURING TRENDS WELL AND IS BEING IGNORED.
CHANGES WITH THIS UPDATE INCLUDE CUTTING POPS BACK TO 40-50 PERCENT
FOR THE REMAINDER OF THE NIGHT AND SLASHING QPF FORECASTS TO AROUND
0.05 INCHES. WHILE THE LOCATION AND DEGREE OF ISENTROPIC LIFT HAS
PROBABLY BEEN WELL-FORECAST BY THE MODELS ALL ALONG...DRY LIFT
DOESN`T YIELD RAINFALL. BREAKS HAVE EVEN OPENED IN THE OVERCAST DECK
NEAR GEORGETOWN...MYRTLE BEACH AND CONWAY IN THE PAST HOUR. :(
AN INVERTED TROUGH JUST OFFSHORE IS THE SURFACE FEATURE WE ARE
WATCHING THIS EVENING. IT EXTENDS NORTH FROM A WEAK LOW JUST EAST OF
JACKSONVILLE FL. IN THE UPPER LEVELS A SHORTWAVE TROUGH ACROSS THE
SOUTHERN AND CENTRAL APPALACHIANS WILL SWEEP OFFSHORE AFTER
MIDNIGHT. A PUSH OF WESTERLY MID-LEVEL WINDS BEHIND THIS FEATURE
SHOULD HELP NUDGE THE SURFACE TROUGH FARTHER OFFSHORE AS WELL. OUR
LOW LEVEL WINDS WILL BECOME QUITE LIGHT AS THE TROUGH SHIFTS
OFFSHORE LATE...WITH LITTLE OPPORTUNITY FOR THE CHILLIER AIR IN THE
MOUNTAINS TO ADVECT DOWN TOWARD THE COAST.
OVERNIGHT LOW TEMPERATURES ARE STILL EXPECTED TO RANGE FROM THE MID
50S ON THE COAST TO AROUND 50 ON THE INTERSTATE 95 CORRIDOR. THIS IS
ON THE HIGH END OF MOS GUIDANCE BUT SEEMS REASONABLE GIVEN
PREDOMINANTLY CLOUDY SKIES AND NO SUBSTANTIAL COLD ADVECTION EXPECTED
THROUGH DAYBREAK.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...A COASTAL TROUGH WILL BE PRESENT OFFSHORE ON
SAT. THIS TROUGH WILL LIFT N AND THEN DISSIPATE THROUGH SAT NIGHT.
EXPECT ANY LIGHT PRECIPITATION TO BE ENDING DURING SAT. INLAND
AREAS SHOULD SEE AN END TO THE SHOWERS IN THE MORNING. SHOWERS MAY
LINGER ALONG THE COAST INTO THE AFTERNOON...ESPECIALLY ACROSS THE
CAPE FEAR COAST IN CLOSEST PROXIMITY TO THE TROUGH. MOISTURE
PROFILES AND MODEL SOUNDINGS SHOW A GRADUAL DECREASE IN MOISTURE
ON SAT. A PRONOUNCED NEAR SURFACE INVERSION LINGERS INTO SAT
MORNING...BUT EVENTUALLY THE LOW-LEVEL MOISTURE DOES SCOUR OUT.
THIS SHOULD ALLOW PARTIAL SUNSHINE TO DEVELOP SAT AFTERNOON WITH
THE GREATEST CLOUD COVER LIKELY PERSISTING ACROSS THE CAPE FEAR
REGION. A DEEPENING AND STRENGTHENING S TO SW FLOW WILL ENVELOP
THE AREA SUN AND SUN NIGHT. ANOTHER PRONOUNCED LOW-LEVEL INVERSION
IS EXPECTED TO DEVELOP SAT NIGHT AND THIS WILL LINGER INTO SUN
MORNING. THIS INVERSION SHOULD ALLOW LOW STRATUS TO DEVELOP AND
PERSIST INTO A GOOD PORTION OF SUN MORNING. AT THE SAME TIME...MID
AND HIGH LEVEL MOISTURE WILL BE INCREASING AS PRECIPITABLE WATER
VALUES CLIMB TO ABOUT AN INCH AND THREE- QUARTERS SUN EVE AND
NIGHT. THUS...SUN LOOKS TO BE A RATHER CLOUDY DAY THROUGHOUT. THE
COLUMN BECOMES SUFFICIENTLY MOIST IF NOT SATURATED THROUGH A DEEP
LAYER SUN NIGHT AND WILL SHOW POPS INCREASING TO LIKELY OVERNIGHT.
IT IS POSSIBLE SHOWERS DEVELOP EARLIER ON SUN...BUT MOST OF THE
RAINFALL IS EXPECTED SUN NIGHT AND POSSIBLY INTO MON. AT THIS TIME
WILL KEEP MENTION OF ONLY SHOWERS. HOWEVER...INCREASING CAPE
VALUES WERE NOTED AND SO THERE IS A SMALL CHANCE FOR A RUMBLE OF
THUNDER ALTHOUGH AT THIS TIME...FEEL THE RISK WILL BE CONFINED TO
OFFSHORE AREAS WHERE BAROCLINICITY WILL BE HIGHEST.
TEMPS WILL BE A DEG OR TWO ABOVE NORMAL BY DAY AS DEVELOPING WARM
AIR ADVECTION IS MODERATED BY CONSIDERABLE CLOUD COVER...ESPECIALLY
ON SUN. THIS WILL PUT HIGH TEMPS MAINLY IN THE LOWER TO PERHAPS MID
70S. LOW TEMPS WILL HOWEVER BE WELL ABOVE NORMAL...IN THE 50S SAT
NIGHT AND IN THE 60S SUN NIGHT. THE NORMAL LOW TEMPS FOR MID NOV ARE
IN THE MID 40S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 3 PM FRIDAY...THE MID LEVEL PATTERN WILL CONSIST OF MAINLY A
FLAT/ZONAL FLOW BEYOND MONDAY WHEN A WEAKENING TROUGH WILL USHER
THROUGH ANOTHER FAST MOVING FRONT. I DID MAINTAIN THE LIKELY POPS
WITH THIS FEATURE FOR ALL OF MONDAY...AT LEAST THROUGH 0000 UTC
TUESDAY AS THERE REMAINS JUST ENOUGH DISAGREEMENT IN TIMING BETWEEN
THE FASTER GFS SOLUTIONS AND SLOWER WPC PREFERRED ECMWF ENSEMBLE
MEAN. WEEKEND SHIFTS SHOULD BE ABLE TO FINE TUNE TIMING.
BEYOND THIS...HIGH PRESSURE BUILDS IN BUT THE COLD AIR ADVECTION IS
DELAYED SOMEWHAT AS 850MB TEMPERATURES DON/T BOTTOM OUT UNTIL
WEDNESDAY AFTERNOON. OVERALL TEMPERATURE TRENDS ARE SOMEWHAT BELOW
NORMAL WITH WEDNESDAY AND THURSDAY THE COOLEST WARMING A BIT FRIDAY
BASICALLY DUE TO AIR MASS MODIFICATION AND THE DEVELOPMENT OF A
COASTAL TROUGH. TUESDAY TEMPERATURES ARE RIGHT AROUND NORMAL.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 06Z...RADAR IMAGERY INDICATES THE SHOWERS ASSOCIATED WITH A
COASTAL TROUGH HAVE REMAINED OFFSHORE TONIGHT. PRIMARILY VFR CIGS
PREVAIL ACROSS THE AREA AS THE MODELS SEEM TO HAVE OVER-ESTIMATED
THE AVAILABLE MOISTURE FOR PCPN. BASED ON THESE TRENDS...HAVE CUT
BACK PCPN IN THE TAFS TO ONLY MENTION VCSH INTO THE MORNING HOURS.
CALM TO LIGHT WINDS ARE EXPECTED OVERNIGHT...BUT THE CLOUD COVER
SHOULD KEEP VSBYS FROM SIGNIFICANTLY DROPPING. CANNOT RULE OUT SOME
MVFR VSBYS/TEMPO IFR CIGS BEFORE DAYBREAK...BUT AGAIN THE POOR
PERFORMANCE OF THE MODELS WITH REGARDS TO THE MOISTURE PROFILES
LOWERS MY CONFIDENCE. DO NOT ANTICIPATE ANYTHING WORSE THAN MVFR
CONDITIONS OVERNIGHT ATTM. EXPECT MAINLY VFR DURING THE DAYTIME WITH
E-NE WINDS AROUND 5 KTS. FOG COULD BE AN ISSUE EARLY SUNDAY...BUT
ANY VSBY IMPACTS WILL LIKELY OCCUR AFTER THE VALID TAF PERIOD.
EXTENDED OUTLOOK...MVFR/IFR FOG POSSIBLE ON SUNDAY MORNING. EXPECT
SHOWERS AND PERIODS OF MVFR/IFR EARLY MONDAY WITH A COLD FRONT.
STRATUS POSSIBLE ALONG THE COAST ON WEDNESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 12:30 AM SATURDAY...NO CHANGES TO THE FORECAST WITH THE
LATEST UPDATE. PREVIOUS DISCUSSION FOLLOWS:
AN INVERTED SURFACE TROUGH EXTENDS SOUTH-TO-NORTH ACROSS THE
CAROLINA COASTAL WATERS. ITS EXACT LOCATION IS TOUGH TO PIN DOWN
WITH SPARSE OBSERVATIONS...BUT BASED ON WIND DIRECTIONS AT THE
BEACHES AND AT THE FRYING PAN SHOALS BUOY PROBABLY LIES 10-15
MILES EAST OF CAPE FEAR AND 40-45 MILES EAST OF MYRTLE BEACH AND
GEORGETOWN. THIS TROUGH SHOULD WEAKEN AND SHIFT EAST AND FARTHER
OFFSHORE OVERNIGHT AS AN UPPER LEVEL TROUGH PASSES OVERHEAD AFTER
MIDNIGHT.
WINDS EAST OF THE TROUGH AXIS ARE GENERALLY E-NE IN THE 8-12 KNOT
RANGE...WHILE EAST OF THE TROUGH OVER THE OFFSHORE WATERS THEY ARE
SOUTHEAST NEAR 15 KNOTS AT THE FRYING PAN SHOALS BUOY WITH
GUSTS TO 17 KNOTS. SEAS HAVE BUILT TO 4 FT OFFSHORE AND TO 2.5 FEET
AT THE BUOY JUST SOUTH OF CAPE FEAR.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...A COASTAL TROUGH WILL BISECT THE WATERS ON
SAT. THIS TROUGH WILL LIFT N OF THE AREA SAT NIGHT AND DISSIPATE.
A COLD FRONT WILL APPROACH FROM THE W SUN AND SUN NIGHT. THE
APPROACH OF THIS FRONT WILL GRADUALLY TIGHTEN WHAT WILL OTHERWISE
BE A SLACK GRADIENT THIS WEEKEND. THE STRONGEST WINDS ARE EXPECTED
SUN NIGHT. THE WINDS WILL BE LIGHT ENE TO E SAT. THE DIRECTION
WILL VEER TO SE SAT NIGHT AND TO S ON SUN. WINDS WILL EVENTUALLY
COME AROUND TO SW MON MORNING. WIND SPEEDS WILL REACH UP TO 15 TO
20 KT SUN NIGHT. SEAS WILL BE 2 TO 3 FT SAT THROUGH SUN AND THEN
BUILD TO 4 TO POSSIBLY 5 FT SUN NIGHT. AN 8 TO 10 SECOND SE SWELL
WILL BECOME MORE SIGNIFICANT LATE SUN AND SUN NIGHT.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 3 PM FRIDAY...THE MAIN FEATURE FOR THE MARINE COMMUNITY WILL
BE THE FRONT THAT MOVES ACROSS THE WATERS EARLY IN THE PERIOD. THE
TIMING REMAINS CONFIDENCE CHALLENGED BUT FOR NOW IT LOOKS LIKE A
LATE AFTERNOON WIND SHIFT FROM THE SOUTHWEST TO WEST. NOT THE MOST
DYNAMIC OF SYSTEMS SO WINDS WILL TAKE SOME TIME...BY TUESDAY MORNING
TO REACH MARGINAL SMALL CRAFT CRITERIA WITH A 20-25 KNOT RANGE.
WINDS HAVE A GOOD CHANCE TO STAY ELEVATED AS COLD AIR ADVECTION LAGS
WELL BEHIND THE FRONT AND WILL PROBABLY HOVER AROUND 20 KNOTS
THROUGH THE END OF THE PERIOD. SEAS WILL BUILD WITH THE WINDS FROM
INITIAL VALUES OF 2-4 FEET TO 4-7 FEET BY THE END OF THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...REK
AVIATION...BJR
AREA FORECAST DISCUSSION
NWS BISMARCK ND
106 PM CST SAT NOV 16 2013
.UPDATE...
ISSUED AT 107 PM CST SAT NOV 16 2013
LOW PRESSURE WILL REMAIN OVER THE AREA TODAY AS AN UPPER LEVEL
TROUGH DIGS FROM THE NORTHERN ROCKIES INTO THE NORTHERN PLAINS.
MAIN EARLY AFTERNOON UPDATES WERE TO LOWER TEMPERATURES AS
EXTENSIVE CLOUD COVER AND LIGHT PRECIPITATION WILL LIMIT HEATING.
ALSO ADJUSTED POPS BASED ON LATEST RADAR IMAGERY.
UPDATE ISSUED AT 947 AM CST SAT NOV 16 2013
RADAR RETURNS CONTINUE OVER WESTERN AND NORTH CENTRAL NORTH DAKOTA
AND HAVE EXPANDED AREAL COVERAGE OF SLIGHT CHANCE POPS. ALSO ADDED
A SLIGHT CHANCE OF PRECIPITATION OVER THE FAR SOUTHEAST COUNTIES
AS RETURNS HAVE INCREASED HERE AS WELL OVER THE PAST FEW HOURS.
PRECIPITATION WILL BE RAIN IN THE SOUTHEAST WITH A RAIN SNOW MIX
NORTH AND WEST FOR ANOTHER HOUR OR TWO...BEFORE RAIN THIS
AFTERNOON. PRECIPITATION AMOUNTS TODAY WILL BE LIGHT. A FEW AREAS
OF SUN OVER THE FAR SOUTH CENTRAL YET THIS MORNING...BUT CLOUDS
WILL CONTINUE TO INCREASE DURING THE DAY. WILL TAKE A CLOSER LOOK
AT TEMPERATURES LATE MORNING/EARLY THIS AFTERNOON.
UPDATE ISSUED AT 629 AM CST SAT NOV 16 2013
EARLY MORNING RADAR MOSAIC SHOWS A FEW RETURNS ACROSS THE NORTHWEST
AND SOUTHEAST PARTS OF THE STATE. THE 12Z KBIS SOUNDING SHOWS
THERE IS QUITE A BIT OF DRY LOW LEVEL AIR TO OVERCOME...SO MAINLY
VIRGA IS EXPECTED OVER THE NEXT FEW HOURS. THE EXCEPTION WOULD BE
IN THE NORTHWEST WHERE THE LATEST RAP SUGGESTS THERE COULD BE
LIGHT PRECIPITATION THIS MORNING. ESTEVAN HAS REPORTED A FEW
FLURRIES IN THE PAST HOUR...SO WILL INCREASE THE COVERAGE OF THE
SLIGHT CHANCES POPS THIS MORNING TO FALL IN LINE CLOSER TO THE
COVERAGE SHOWN BY THE RAP. DO NOT EXPECT MUCH ACCUMULATION...THUS
KEPT POPS LOW.
UPDATED TEMPERATURES TO BETTER REFLECT CURRENT CONDITIONS...OTHERWISE
THE FORECAST LOOKS TO BE IN GOOD SHAPE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 310 AM CST SAT NOV 16 2013
A WINTER WEATHER ADVISORY WILL NOT BE ISSUED FOR THIS EVENT...AT
LEAST NOT WITH THIS FORECAST CYCLE...BASED ON CURRENT EXPECTATIONS
OF JUST AN INCH OR TWO TOTAL SNOWFALL SATURDAY NIGHT THROUGH
SUNDAY. WE ARE DEEP ENOUGH NOW INTO THE SNOW SEASON WHERE AN
ADVISORY IS NOT JUSTIFIED. WE MAY OPT TO HIGHLIGHT THE EVENT
THROUGH A SPECIAL WEATHER STATEMENT AS SUNDAY WILL BE WINDY AND
MUCH COLDER.
TWO POINTS OF INTEREST FOR THE SHORT TERM. THE FIRST IS THE ABOVE
NORMAL TEMPERATURES FOR TODAY...SATURDAY. ENJOY IT IF YOU CAN AS
HIGH TEMPERATURES WILL BE 5 TO 10 DEGREES ABOVE MID NOVEMBER
NORMALS. COOLER THAN FRIDAY...BUT STILL ABOVE NORMAL. THE SECOND
POINT IS THE COLDER WEATHER MOVING IN FOR TONIGHT WITH RAIN
CHANGING TO SNOW.
FOR TODAY...SURFACE HIGH PRESSURE AND MID LEVEL RIDGING WILL SLIDE
/ SHIFT OFF TO THE EAST AS AN OPEN MID LEVEL WAVE APPROACHES FROM
THE NORTHWEST. AHEAD OF THE SURFACE LOW...CLOUDS WERE ALREADY
ADVANCING INTO THE WESTERN PART OF THE FORECAST AREA...AND WILL
MAKE FOR A MOSTLY CLOUDY AFTERNOON ACROSS ALL OF THE FORECAST
AREA. A WEAK WARM FRONT SLIDING THROUGH LATER TODAY WILL PUSH
TEMPERATURES INTO THE 40S FOR HIGHS...AND BRING THE CHANCE FOR AN
ISOLATED RAIN SHOWER TO THE WEST.
FOR TONIGHT...LARGE SCALE LIFTING INCREASES AS THE MID LEVEL AND
SURFACE WAVE APPROACH. COOLING WILL BE DELAYED...AS WE WILL BE ON
THE SO CALLED WARM SIDE OF STORM...UNTIL AFTER 9 PM OR SO.
PRECIPITATION STARTS AS RAIN AND THEN TRANSITIONS TO SNOW AS THE
ATMOSPHERE COOLS. THE CHANGE TO SNOW OCCURS ALONG HIGHWAY 2 AROUND
9 PM CST...AND ALONG I-94 AROUND 11 PM OR MIDNIGHT CST. THE SNOW
THROUGH DAYBREAK SUNDAY WILL BE LIGHT IN INTENSITY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 310 AM CST SAT NOV 16 2013
SUNDAY WILL BEGIN WITH A LARGE TROUGH ACROSS THE CENTRAL UNITED
STATES WHICH HELPS PUSH ANOTHER COLD FRONT THROUGH THE NORTHERN
PLAINS. SHORT TERM MODELS HAVE COME INTO BETTER AGREEMENT
REGARDING PRECIPITATION CHANCES...AND SUGGEST HIGHER CHANCES FOR
SUNDAY MORNING. HAVE INCREASED POPS ACCORDINGLY AND NOW HAVE POPS
APPROACHING CATEGORICAL IN THE NORTHWEST.
IT APPEARS THE MAJORITY OF THE PRECIPITATION WILL FALL AS SNOW AS
COLDER AIR WORKS IT WAY INTO THE REGION. SNOW AMOUNTS SUNDAY SHOULD
GENERALLY STAY LESS THAN 1.5 INCHES. HIGH TEMPERATURES IN THE MID
20S TO MID 30S ON SUNDAY WILL BE MUCH COOLER THAN THOSE EXPECTED
FOR TODAY (SATURDAY). THE COLDER TEMPERATURES COMBINED WITH A
GUSTY NORTHWESTERLY WIND WILL MAKE FOR A RATHER BLUSTERY DAY.
SURFACE HIGH PRESSURE BUILDS IN SUNDAY NIGHT...AND WILL GO DRY
ACROSS THE FORECAST AREA. THAT BEING SAID...SOME MODEL SOLUTIONS DO
SUGGEST THE POSSIBILITY OF LINGERING LIGHT SNOW IN THE FAR EAST
EARLY SUNDAY EVENING...BUT DID NOT FEEL CONFIDENT ENOUGH TO ADD A
POP AT THE MOMENT.
H5 HEIGHTS RISE MONDAY WITH WARMER AIR RETURNING TO THE NORTHERN
PLAINS FOR EARLY NEXT WEEK. THE WARMER AIR DOES NOT STAY IN PLACE
FOR VERY LONG WITH ANOTHER COLD FRONT DROPPING ACROSS DAKOTAS
WEDNESDAY INTO WEDNESDAY NIGHT. THE FRONT WILL ALSO BRING ANOTHER
CHANCE OF PRECIPITATION...AGAIN MAINLY IN THE FORM OF SNOW. AT THE
MOMENT...IT DOES NOT APPEAR TO BE A SIGNIFICANT PRECIPITATION
MAKER. DRIER WEATHER TAKES HOLD AGAIN FOR THURSDAY AND FRIDAY.
WARMER AIR RETURNS AGAIN FRIDAY INTO NEXT WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 107 PM CST SAT NOV 16 2013
THIS AFTERNOON RAIN WILL IMPACT KISN AND KMOT...MOVING INTO
KDIK...KBIS...AND KJMS THROUGH THE EVENING. RAIN IS EXPECTED TO TURN
TO SNOW INTO THE OVERNIGHT HOURS. THERE IS SOME UNCERTAINTY AS TO
WHEN THE CHANGEOVER WILL OCCUR. DURING THE TAF PERIOD...EXPECT MVFR
CONDITIONS WITH LOWER CEILINGS AND REDUCED VISIBILITIES. WINDS WILL
GRADUALLY INCREASE THROUGH THE END OF THE PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...JPM
LONG TERM...CK
AVIATION...AC
AREA FORECAST DISCUSSION
NWS BISMARCK ND
947 AM CST SAT NOV 16 2013
.UPDATE...
ISSUED AT 947 AM CST SAT NOV 16 2013
RADAR RETURNS CONTINUE OVER WESTERN AND NORTH CENTRAL NORTH DAKOTA
AND HAVE EXPANDED AREAL COVERAGE OF SLIGHT CHANCE POPS. ALSO ADDED
A SLIGHT CHANCE OF PRECIPITATION OVER THE FAR SOUTHEAST COUNTIES
AS RETURNS HAVE INCREASED HERE AS WELL OVER THE PAST FEW HOURS.
PRECIPITATION WILL BE RAIN IN THE SOUTHEAST WITH A RAIN SNOW MIX
NORTH AND WEST FOR ANOTHER HOUR OR TWO...BEFORE RAIN THIS
AFTERNOON. PRECIPITATION AMOUNTS TODAY WILL BE LIGHT. A FEW AREAS
OF SUN OVER THE FAR SOUTH CENTRAL YET THIS MORNING...BUT CLOUDS
WILL CONTINUE TO INCREASE DURING THE DAY. WILL TAKE A CLOSER LOOK
AT TEMPERATURES LATE MORNING/EARLY THIS AFTERNOON.
UPDATE ISSUED AT 629 AM CST SAT NOV 16 2013
EARLY MORNING RADAR MOSAIC SHOWS A FEW RETURNS ACROSS THE NORTHWEST
AND SOUTHEAST PARTS OF THE STATE. THE 12Z KBIS SOUNDING SHOWS
THERE IS QUITE A BIT OF DRY LOW LEVEL AIR TO OVERCOME...SO MAINLY
VIRGA IS EXPECTED OVER THE NEXT FEW HOURS. THE EXCEPTION WOULD BE
IN THE NORTHWEST WHERE THE LATEST RAP SUGGESTS THERE COULD BE
LIGHT PRECIPITATION THIS MORNING. ESTEVAN HAS REPORTED A FEW
FLURRIES IN THE PAST HOUR...SO WILL INCREASE THE COVERAGE OF THE
SLIGHT CHANCES POPS THIS MORNING TO FALL IN LINE CLOSER TO THE
COVERAGE SHOWN BY THE RAP. DO NOT EXPECT MUCH ACCUMULATION...THUS
KEPT POPS LOW.
UPDATED TEMPERATURES TO BETTER REFLECT CURRENT CONDITIONS...OTHERWISE
THE FORECAST LOOKS TO BE IN GOOD SHAPE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 310 AM CST SAT NOV 16 2013
A WINTER WEATHER ADVISORY WILL NOT BE ISSUED FOR THIS EVENT...AT
LEAST NOT WITH THIS FORECAST CYCLE...BASED ON CURRENT EXPECTATIONS
OF JUST AN INCH OR TWO TOTAL SNOWFALL SATURDAY NIGHT THROUGH
SUNDAY. WE ARE DEEP ENOUGH NOW INTO THE SNOW SEASON WHERE AN
ADVISORY IS NOT JUSTIFIED. WE MAY OPT TO HIGHLIGHT THE EVENT
THROUGH A SPECIAL WEATHER STATEMENT AS SUNDAY WILL BE WINDY AND
MUCH COLDER.
TWO POINTS OF INTEREST FOR THE SHORT TERM. THE FIRST IS THE ABOVE
NORMAL TEMPERATURES FOR TODAY...SATURDAY. ENJOY IT IF YOU CAN AS
HIGH TEMPERATURES WILL BE 5 TO 10 DEGREES ABOVE MID NOVEMBER
NORMALS. COOLER THAN FRIDAY...BUT STILL ABOVE NORMAL. THE SECOND
POINT IS THE COLDER WEATHER MOVING IN FOR TONIGHT WITH RAIN
CHANGING TO SNOW.
FOR TODAY...SURFACE HIGH PRESSURE AND MID LEVEL RIDGING WILL SLIDE
/ SHIFT OFF TO THE EAST AS AN OPEN MID LEVEL WAVE APPROACHES FROM
THE NORTHWEST. AHEAD OF THE SURFACE LOW...CLOUDS WERE ALREADY
ADVANCING INTO THE WESTERN PART OF THE FORECAST AREA...AND WILL
MAKE FOR A MOSTLY CLOUDY AFTERNOON ACROSS ALL OF THE FORECAST
AREA. A WEAK WARM FRONT SLIDING THROUGH LATER TODAY WILL PUSH
TEMPERATURES INTO THE 40S FOR HIGHS...AND BRING THE CHANCE FOR AN
ISOLATED RAIN SHOWER TO THE WEST.
FOR TONIGHT...LARGE SCALE LIFTING INCREASES AS THE MID LEVEL AND
SURFACE WAVE APPROACH. COOLING WILL BE DELAYED...AS WE WILL BE ON
THE SO CALLED WARM SIDE OF STORM...UNTIL AFTER 9 PM OR SO.
PRECIPITATION STARTS AS RAIN AND THEN TRANSITIONS TO SNOW AS THE
ATMOSPHERE COOLS. THE CHANGE TO SNOW OCCURS ALONG HIGHWAY 2 AROUND
9 PM CST...AND ALONG I-94 AROUND 11 PM OR MIDNIGHT CST. THE SNOW
THROUGH DAYBREAK SUNDAY WILL BE LIGHT IN INTENSITY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 310 AM CST SAT NOV 16 2013
SUNDAY WILL BEGIN WITH A LARGE TROUGH ACROSS THE CENTRAL UNITED
STATES WHICH HELPS PUSH ANOTHER COLD FRONT THROUGH THE NORTHERN
PLAINS. SHORT TERM MODELS HAVE COME INTO BETTER AGREEMENT
REGARDING PRECIPITATION CHANCES...AND SUGGEST HIGHER CHANCES FOR
SUNDAY MORNING. HAVE INCREASED POPS ACCORDINGLY AND NOW HAVE POPS
APPROACHING CATEGORICAL IN THE NORTHWEST.
IT APPEARS THE MAJORITY OF THE PRECIPITATION WILL FALL AS SNOW AS
COLDER AIR WORKS IT WAY INTO THE REGION. SNOW AMOUNTS SUNDAY SHOULD
GENERALLY STAY LESS THAN 1.5 INCHES. HIGH TEMPERATURES IN THE MID
20S TO MID 30S ON SUNDAY WILL BE MUCH COOLER THAN THOSE EXPECTED
FOR TODAY (SATURDAY). THE COLDER TEMPERATURES COMBINED WITH A
GUSTY NORTHWESTERLY WIND WILL MAKE FOR A RATHER BLUSTERY DAY.
SURFACE HIGH PRESSURE BUILDS IN SUNDAY NIGHT...AND WILL GO DRY
ACROSS THE FORECAST AREA. THAT BEING SAID...SOME MODEL SOLUTIONS DO
SUGGEST THE POSSIBILITY OF LINGERING LIGHT SNOW IN THE FAR EAST
EARLY SUNDAY EVENING...BUT DID NOT FEEL CONFIDENT ENOUGH TO ADD A
POP AT THE MOMENT.
H5 HEIGHTS RISE MONDAY WITH WARMER AIR RETURNING TO THE NORTHERN
PLAINS FOR EARLY NEXT WEEK. THE WARMER AIR DOES NOT STAY IN PLACE
FOR VERY LONG WITH ANOTHER COLD FRONT DROPPING ACROSS DAKOTAS
WEDNESDAY INTO WEDNESDAY NIGHT. THE FRONT WILL ALSO BRING ANOTHER
CHANCE OF PRECIPITATION...AGAIN MAINLY IN THE FORM OF SNOW. AT THE
MOMENT...IT DOES NOT APPEAR TO BE A SIGNIFICANT PRECIPITATION
MAKER. DRIER WEATHER TAKES HOLD AGAIN FOR THURSDAY AND FRIDAY.
WARMER AIR RETURNS AGAIN FRIDAY INTO NEXT WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 947 AM CST SAT NOV 16 2013
VFR WEATHER WILL PREVAIL THROUGH THE DAYLIGHT HOURS OF SATURDAY.
HIGH AND MID LEVEL CLOUDS WILL INCREASE FROM THE NORTHWEST THROUGH
THE DAY...AND LOWER AS MOISTURE INCREASES AFTER 16/18Z. A FEW SNOW
FLURRIES ARE POSSIBLE FOR THE AREA AROUND KISN THIS MORNING...THEN
ISOLATED RAIN SHOWERS SPREADING THROUGH KISN-KMOT-KDIK AFTER
16/22Z. SURFACE WINDS SATURDAY WILL BE 10 KNOTS OR LESS. THE RAIN
SHOWERS WILL CHANGE TO SNOW AS LOW PRESSURE APPROACHES AFTER
17/03Z...WITH MVFR CIGS ALSO POSSIBLE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...JPM
LONG TERM...CK
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
643 AM CST SAT NOV 16 2013
.UPDATE...
ISSUED AT 629 AM CST SAT NOV 16 2013
EARLY MORNING RADAR MOSAIC SHOWS A FEW RETURNS ACROSS THE NORTHWEST
AND SOUTHEAST PARTS OF THE STATE. THE 12Z KBIS SOUNDING SHOWS
THERE IS QUITE A BIT OF DRY LOW LEVEL AIR TO OVERCOME...SO MAINLY
VIRGA IS EXPECTED OVER THE NEXT FEW HOURS. THE EXCEPTION WOULD BE
IN THE NORTHWEST WHERE THE LATEST RAP SUGGESTS THERE COULD BE
LIGHT PRECIPITATION THIS MORNING. ESTEVAN HAS REPORTED A FEW
FLURRIES IN THE PAST HOUR...SO WILL INCREASE THE COVERAGE OF THE
SLIGHT CHANCES POPS THIS MORNING TO FALL IN LINE CLOSER TO THE
COVERAGE SHOWN BY THE RAP. DO NOT EXPECT MUCH ACCUMULATION...THUS
KEPT POPS LOW.
UPDATED TEMPERATURES TO BETTER REFLECT CURRENT CONDITIONS...OTHERWISE
THE FORECAST LOOKS TO BE IN GOOD SHAPE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 310 AM CST SAT NOV 16 2013
A WINTER WEATHER ADVISORY WILL NOT BE ISSUED FOR THIS EVENT...AT
LEAST NOT WITH THIS FORECAST CYCLE...BASED ON CURRENT EXPECTATIONS
OF JUST AN INCH OR TWO TOTAL SNOWFALL SATURDAY NIGHT THROUGH
SUNDAY. WE ARE DEEP ENOUGH NOW INTO THE SNOW SEASON WHERE AN
ADVISORY IS NOT JUSTIFIED. WE MAY OPT TO HIGHLIGHT THE EVENT
THROUGH A SPECIAL WEATHER STATEMENT AS SUNDAY WILL BE WINDY AND
MUCH COLDER.
TWO POINTS OF INTEREST FOR THE SHORT TERM. THE FIRST IS THE ABOVE
NORMAL TEMPERATURES FOR TODAY...SATURDAY. ENJOY IT IF YOU CAN AS
HIGH TEMPERATURES WILL BE 5 TO 10 DEGREES ABOVE MID NOVEMBER
NORMALS. COOLER THAN FRIDAY...BUT STILL ABOVE NORMAL. THE SECOND
POINT IS THE COLDER WEATHER MOVING IN FOR TONIGHT WITH RAIN
CHANGING TO SNOW.
FOR TODAY...SURFACE HIGH PRESSURE AND MID LEVEL RIDGING WILL SLIDE
/ SHIFT OFF TO THE EAST AS AN OPEN MID LEVEL WAVE APPROACHES FROM
THE NORTHWEST. AHEAD OF THE SURFACE LOW...CLOUDS WERE ALREADY
ADVANCING INTO THE WESTERN PART OF THE FORECAST AREA...AND WILL
MAKE FOR A MOSTLY CLOUDY AFTERNOON ACROSS ALL OF THE FORECAST
AREA. A WEAK WARM FRONT SLIDING THROUGH LATER TODAY WILL PUSH
TEMPERATURES INTO THE 40S FOR HIGHS...AND BRING THE CHANCE FOR AN
ISOLATED RAIN SHOWER TO THE WEST.
FOR TONIGHT...LARGE SCALE LIFTING INCREASES AS THE MID LEVEL AND
SURFACE WAVE APPROACH. COOLING WILL BE DELAYED...AS WE WILL BE ON
THE SO CALLED WARM SIDE OF STORM...UNTIL AFTER 9 PM OR SO.
PRECIPITATION STARTS AS RAIN AND THEN TRANSITIONS TO SNOW AS THE
ATMOSPHERE COOLS. THE CHANGE TO SNOW OCCURS ALONG HIGHWAY 2 AROUND
9 PM CST...AND ALONG I-94 AROUND 11 PM OR MIDNIGHT CST. THE SNOW
THROUGH DAYBREAK SUNDAY WILL BE LIGHT IN INTENSITY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 310 AM CST SAT NOV 16 2013
SUNDAY WILL BEGIN WITH A LARGE TROUGH ACROSS THE CENTRAL UNITED
STATES WHICH HELPS PUSH ANOTHER COLD FRONT THROUGH THE NORTHERN
PLAINS. SHORT TERM MODELS HAVE COME INTO BETTER AGREEMENT
REGARDING PRECIPITATION CHANCES...AND SUGGEST HIGHER CHANCES FOR
SUNDAY MORNING. HAVE INCREASED POPS ACCORDINGLY AND NOW HAVE POPS
APPROACHING CATEGORICAL IN THE NORTHWEST.
IT APPEARS THE MAJORITY OF THE PRECIPITATION WILL FALL AS SNOW AS
COLDER AIR WORKS IT WAY INTO THE REGION. SNOW AMOUNTS SUNDAY SHOULD
GENERALLY STAY LESS THAN 1.5 INCHES. HIGH TEMPERATURES IN THE MID
20S TO MID 30S ON SUNDAY WILL BE MUCH COOLER THAN THOSE EXPECTED
FOR TODAY (SATURDAY). THE COLDER TEMPERATURES COMBINED WITH A
GUSTY NORTHWESTERLY WIND WILL MAKE FOR A RATHER BLUSTERY DAY.
SURFACE HIGH PRESSURE BUILDS IN SUNDAY NIGHT...AND WILL GO DRY
ACROSS THE FORECAST AREA. THAT BEING SAID...SOME MODEL SOLUTIONS DO
SUGGEST THE POSSIBILITY OF LINGERING LIGHT SNOW IN THE FAR EAST
EARLY SUNDAY EVENING...BUT DID NOT FEEL CONFIDENT ENOUGH TO ADD A
POP AT THE MOMENT.
H5 HEIGHTS RISE MONDAY WITH WARMER AIR RETURNING TO THE NORTHERN
PLAINS FOR EARLY NEXT WEEK. THE WARMER AIR DOES NOT STAY IN PLACE
FOR VERY LONG WITH ANOTHER COLD FRONT DROPPING ACROSS DAKOTAS
WEDNESDAY INTO WEDNESDAY NIGHT. THE FRONT WILL ALSO BRING ANOTHER
CHANCE OF PRECIPITATION...AGAIN MAINLY IN THE FORM OF SNOW. AT THE
MOMENT...IT DOES NOT APPEAR TO BE A SIGNIFICANT PRECIPITATION
MAKER. DRIER WEATHER TAKES HOLD AGAIN FOR THURSDAY AND FRIDAY.
WARMER AIR RETURNS AGAIN FRIDAY INTO NEXT WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 642 AM CST SAT NOV 16 2013
BRIEF PATCHY FOG IS POSSIBLE AT KJMS EARLY THIS
MORNING...OTHERWISE VFR WEATHER WILL PREVAIL THROUGH THE DAYLIGHT
HOURS OF SATURDAY. HIGH AND MID LEVEL CLOUDS WILL INCREASE FROM
THE NORTHWEST THROUGH THE DAY...AND LOWER AS MOISTURE INCREASES
AFTER 16/18Z. A FEW SNOW FLURRIES ARE POSSIBLE FOR THE AREA
AROUND KISN THIS MORNING...THEN ISOLATED RAIN SHOWERS SPREADING
THROUGH KISN-KMOT-KDIK AFTER 16/22Z. SURFACE WINDS SATURDAY WILL
BE 10 KNOTS OR LESS. THE RAIN SHOWERS WILL CHANGE TO SNOW AS LOW
PRESSURE APPROACHES AFTER 17/03Z...WITH MVFR CIGS ALSO POSSIBLE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CK
SHORT TERM...JPM
LONG TERM...CK
AVIATION...JPM
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1245 AM EST SAT NOV 16 2013
.SYNOPSIS...
DISTURBANCE ALOFT EXITING OVERNIGHT. WARMING TREND THROUGH
THE WEEKEND. STRONG COLD FRONT CROSSES SUNDAY NIGHT. IN FAST FLOW
ALOFT...GUSTY SHOWERS LIKELY. TURNING COLDER MONDAY.
&&
.NEAR TERM /THROUGH TODAY/...
UPDATE...
ENDED THE POPS QUICKER IN THE OVERNIGHT PERIOD PER LOCAL WRF
MODELS AND THE HRRR MODEL. RAIN WEST OF THE TUG FORK RIVER IS MORE
SCATTERED IN NATURE...AND WILL SEE THIS TREND MOVING INTO THE WEST
VIRGINIA COAL FIELDS IN THE NEXT COUPLE OF HOURS.
PREVIOUS DISCUSSION...
RADAR AND SATELLITE IMAGES INDICATE SHOWERS STRUGGLING TO REACH
THE GROUND ACROSS EASTERN KY THIS AFTERNOON. VERY DRY AIR MASS
REMAINS IN PLACE PRODUCING VIRGA FOR THE MOST PART. BELIEVE...THE
COLUMN WILL CONTINUE TO MOISTEN...MAKING FEW OF THESE LIGHT
SHOWERS TO AFFECT THE EASTERN MOUNTAINS LATER THIS EVENING AND
TONIGHT.
BREEZY FLOW WILL SUBSIDE LATER TONIGHT AND BECOME MORE SOUTHERLY
OVERNIGHT. ADDITIONAL LIGHT SHOWERS WILL BE POSSIBLE ACROSS THE
SOUTHERN COAL FIELDS OF WV EARLY SATURDAY.
KEPT POPS REACHING LIKELY THIS EVENING ACROSS THE SOUTHEAST HALF
OF OUR CWA. MINOR CHANGES TO TEMPERATURES NEEDED.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY/...
MODELS ARE IN GOOD AGREEMENT ON THE STRONG COLD FRONT THAT RAPIDLY
MOVES ACROSS SUNDAY EVENING AND SUNDAY NIGHT. GIVEN THE ASSOCIATED
NEGATIVELY TILTED UPPER TROUGH SWINGING UP THROUGH THE GREAT LAKES
WITH A DEEPENING SURFACE LOW...THE MODEL TRENDS OF SPEEDING THE
FRONT UP EVEN MORE SEEMS REASONABLE. THE CMC IS EVEN FASTER THAN THE
OTHER SWEET OF MODELS...WHICH ONE CANNOT RULE OUT...BUT WILL STICK
WITH THE VAST MAJORITY OF GUIDANCE WITH THE TIMING. THIS BRINGS THE
FRONT TO THE OHIO RIVER SUNDAY EVENING AND EXITING THE MOUNTAINS
AFTER MIDNIGHT SUNDAY NIGHT...WELL BEFORE DAWN MONDAY.
IN THIS SYNOPTIC SCENARIO...THE LOW LEVEL WINDS WILL BE QUITE STRONG
AND GUSTY MAINLY ALONG AND JUST AHEAD OF THE FRONT...WITH MODEL
FORECASTS OF 60 TO 65 KNOTS OF SOUTHWEST WINDS AT 850MB PRECEDING
THE FRONT. BEING CLOSER TO THE SURFACE LOW...THESE STRONGEST WINDS
WITH THIS SYSTEM WILL BE ACROSS THE NORTHWEST THIRD OF THE AREA
SUNDAY AFTERNOON AND SUNDAY EVENING. THERE WILL ALSO BE A BAND OF
SHOWERS AND A FEW THUNDERSTORMS AS THE FRONT PASSES THROUGH. GIVEN
ALL OF THIS...THE BEST CHANCE OF STRONG AND GUSTY WINDS...POSSIBLY
DAMAGING WINDS...WILL BE IN THE CONVECTION ALONG AND JUST AHEAD OF
THE FRONT AND ESPECIALLY OVER NORTHWEST PORTIONS OF THE AREA. SPC
ALSO HAS A SLIGHT RISK OF SEVERE STORMS SNEAKING IN FROM THE WEST
SUNDAY EVENING WITH THE FRONT...WITH THE MAIN THREAT BEING DAMAGING
WINDS. THIS IS HIGHLIGHTED IN THE HAZARDOUS WEATHER OUTLOOK PRODUCT.
AFTER A DRY AND MILD SATURDAY NIGHT...SUNDAY ITSELF WILL FEATURE A
LOT OF CLOUDS AND SCATTERED SHOWERS IN THE WARM ADVECTION AND MOIST
SOUTHERLY INFLOW WELL AHEAD OF THE FRONT ITSELF. WHILE CLOUDS WILL
HELP LIMIT MIXING WITH THE INCREASING LOW LEVEL WINDS...ONE CANNOT
RULE OUT AN ISOLATED DAMAGING GUST IN A SHOWER SUNDAY AFTERNOON...
ESPECIALLY NORTHWEST PORTIONS OF THE AREA FOR THE REASONS MENTIONED
ABOVE. LOOK FOR TEMPS SUNDAY TO BE WELL ABOVE NORMAL...AROUND 70...
DESPITE THE CLOUDS.
FRONT BLASTS THRU SUNDAY NIGHT WITH WESTERLY WINDS BRINGING IN A
NICE DRY SLOT BY MONDAY MORNING. LOOK FOR A DRY AND A MODESTLY
COOLER DAY MONDAY AS MOST OF THE COLD ADVECTION REMAINS NORTH OF US.
LATER IN THE DAY MONDAY...AS WINDS DO TURN MORE NORTHWESTERLY...LOOK
FOR INCREASED COLD ADVECTION AND UPSLOPE TO BRING A LOW CHANCE OF
RAIN SHOWERS IN THE NORTHERN WEST VIRGINIA MOUNTAINS.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
GENERALLY QUIET IN THE EXTENDED. SOME SNOW SHOWERS POSSIBLE ACROSS
THE NORTHERN ZONES MONDAY NIGHT AS THE UPPER FLOW TURNS
NORTHWESTERLY BRIEFLY. MAINLY ZONAL FLOW MID WEEK WITH SOME UPPER
RIDGING TAKING HOLD BY WEEKS END. A CHILLY AIRMASS WILL MODIFY TO
NEAR NORMAL BY WEEKS END.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
DISTURBANCE ALOFT EXITING AT 06Z SATURDAY. IT HAS LEFT THE LOW
LEVELS IN HTS-CRW-BKW ON SOUTH SATURATED. HAVE CEILINGS LOWERING
OVER SOUTHERN MOUNTAINS INCLUDING BKW AT TIMES TO AOB 1 THSD FT BKN
IN STRATUS THEN LIFTING AFTER 14Z. WILL HOLD LOWLANDS AROUND HTS-CRW
WITHOUT THAT LOW CEILING FORMING...THINKING MORE SCATTERED AS HIGHER
CLOUDS THIN 06Z TO 12Z.
FROM 14Z THROUGH THE DAY...HAVE LOWEST CEILINGS AROUND THE EASTERN
SLOPES INCLUDING POCAHONTAS COUNTY AT 1 TO 2 THSD FT BKN...ALSO SOME
2 THSD FT CEILINGS POSSIBLE IN NORTHEAST KENTUCKY AND SOUTHEAST IN
THE MOIST 925 MB SOUTHERLY FLOW. IN BETWEEN THOSE AREAS...FOR THE
WESTERN SLOPES...INCLUDING CRW-PKB-CKB HAVE CEILINGS HIGHER MOSTLY 3
TO 5 THSD FT BKN.
BY 06Z SUNDAY...CEILINGS REMAINING LOW ALONG THE EASTERN SLOPES WITH
SOME AOB 1 THSD FT BKN AND VSBY BLO 3 MILES IN FOG ACROSS HIGH
TERRAIN. TO THE WEEST...BY 06Z...SHOWERS MAY REACH INTO PORTIONS
OF SOUTHEAST OHIO WITH VSBY NEAR 5 MILES.
THE LOW LEVEL FLOW WILL START TO INCREASE 00Z TO 06Z SUNDAY.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z SUNDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: IN SOUTHERN COUNTIES THROUGH 14Z...WITH LOW
LEVELS SATURATED FROM PREVIOUS LIGHT RAIN...SOME STRATUS CEILINGS
AOB 1 THSD FT COULD FORM IN THE WESTERN LOWLANDS AROUND HTS-CRW.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SAT 11/16/13
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EST 1HRLY 01 02 03 04 05 06 07 08 09 10 11 12
CRW CONSISTENCY H H H H M M M H M M M H
HTS CONSISTENCY H H M M M M M M M M M H
BKW CONSISTENCY M M M M M M M L M M M M
EKN CONSISTENCY M H H H H H H H M M M H
PKB CONSISTENCY H H H H H H H H H M M H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z SUNDAY...
IFR IN STRATUS POSSIBLE ON THE EASTERN SLOPES OF THE WV MOUNTAINS
THROUGH 15Z SUNDAY MORNING...INCLUDING THE GREENBRIER VALLEY.
IN STRONG WIND FLOW AREA WIDE...IFR ALSO POSSIBLE IN GUSTY RAIN
SHOWERS SUNDAY AFTERNOON AND SUNDAY NIGHT...AHEAD OF...AND ALONG
COLD FRONT. EMBEDDED THUNDER POSSIBLE JUST AHEAD OF THE FRONT SUNDAY
EVENING.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB/ARJ/JMV/30
NEAR TERM...ARJ/26
SHORT TERM...JMV
LONG TERM...30
AVIATION...KTB
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
924 PM EST SUN NOV 17 2013
.SYNOPSIS...
A STRONG COLD FRONT IS EXPECTED TO PUSH THROUGH THE FORECAST AREA
TONIGHT INTO EARLY MONDAY...FOLLOWED BY COLD CANADIAN HIGH PRESSURE
BUILDING OVER THE REGION THROUGH THE MIDDLE OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
AS OF 920 PM...A SMALL CLUSTER OF THUNDERSTORMS WAS TRACKING ACROSS
CHESTER...SC AT 40 MPH. OTHERWISE...AREAS OF LIGHT RAIN AND HEAVY
DRIZZLE WILL REMAIN ACROSS THE FORECAST AREA THROUGH THE REST OF THE
EVENING. A THIN LINE OF ORGANIZED TSRA EXISTED ACROSS MIDDLE
KY/TN...TRACKING SE AT 35 MPH. AT THIS RATE...THE LEADING EDGE OF
THE LINE COULD REACH GRAHAM AND SWAIN COUNTIES AROUND 5Z.
HOWEVER...THE TN BORDER COUNTIES MAY THE GREATEST COVERAGE BETWEEN
5-7Z. THE LATEST RUN OF THE HRRR INDICATES THAT THE CONVECTION WILL
WEAKEN GRADUALLY ACROSS EASTERN TN...REACHING THE NC COUNTIES WILL
DECREASED REFLECTIVITY AND SHORTER LINE SEGMENTS. THE LATEST
MESOSCALE ANALYSIS INDICATES NO INSTABILITY ACROSS THE FORECAST
AREA. HOWEVER...A BAND OF WEAK VALUES OF CAPE MAY POOL ALONG AND
AHEAD OF THE CONVECTION. THE FORECAST AND HWO APPEARS ON TRACK.
AS OF 7 PM...AREAS OF RAIN AND HEAVY DRIZZLE WILL REMAIN ACROSS THE
FORECAST AREA THIS EVENING AND INTO EARLY MON MORNING. THE PRIMARY
FORECAST CONCERN WILL BE ASSOCIATED WITH THE PRE FRONTAL BAND OF
TSRA...LOCATED OVER MIDDLE AND WESTERN KY/TN. 22Z HRRR INDICATES
THAT THE BAND WILL APPROACH THE NC/TN LINE BY 7Z. THROUGH 9Z...HRRR
INDICATES THAT LINE SEGMENTS OF SHRA/TSRA WILL PUSH ACROSS THE
MTNS...TRACKING ACROSS THE NC FOOTHILLS. PRE FRONT NAM12 SHERB 0-3
KM VALUES RANGE FROM .6-.7. ALSO...0-3 KM EHI VALUES DECREASE FROM
.7-.4 M2/S2 FROM WEST TO EAST. I WOULD EXPECT THAT THE LINE OF
CONVECTION WILL CROSS THE SPINE OF THE APPALACHIANS LATE
TONIGHT...LARGELY INTACT. HOWEVER...THE ENVIRONMENT DOES NOT FAVOR
AN ORGANIZED BAND OF CONVECTION ACROSS THE THE FOOTHILLS AND
PIEDMONT. THE HWO APPEARS WELL WORDED...NO CHANGES PLANNED AT THIS
TIME. OTHERWISE...TEMPS SHOULD REMAIN NEARLY STEADY THIS EVENING AND
TONIGHT.
AS OF MID AFTERNOON...SHOWERS CONTINUE TO DEVELOP AND FILL IN ACROSS
NE GEORGIA...THE UPSTATE...AND THE NC FOOTHILLS...WHILE AN AREA OF
PRECIP MOVES ACRS THE NC MTNS FROM ERN TN. PRECIP CHANCES GRADUALLY
RAMP UP THROUGH THE REST OF THE DAYLIGHT HOURS TO ACCOUNT FOR THIS.
TEMPS ARE WARMER THAN EXPECTED ACROSS METRO CHARLOTTE...SO HIGH
TEMPS WERE RAISED THERE.
THE FIRST BATCH OF PRECIP WAS BEING DRIVEN BY THE PASSAGE OF A SHORT
WAVE...SEEN ON THE WATER VAPOR IMAGERY. THERE COULD BE A LULL IN
ACTIVITY MOVING IN FROM THE WEST THIS EVENING...ALTHO LOW LEVEL
MOISTURE AND FORCING WILL REMAIN IN PLACE. THIS DOES NOT LEAVE
ENOUGH CONFIDENCE TO TEMPORARILY LOWER THE PRECIP CHANCES AHEAD OF
THE FRONT...BUT SOME TWEAKING MIGHT BE DONE DURING THE EARLY EVENING
IF REDEVELOPMENT IS NOT SEEN. MOST SIGNS POINT TO A FRONTAL PASSAGE
DURING THE EARLY MORNING HOURS ACROSS MOST OF THE FCST AREA...WITH
THE FRONT STRETCHED OUT OVER THE PIEDMONT AT SUNRISE. THE MAIN ISSUE
IS THE SEVERE WEATHER POTENTIAL. ALTHO SHEAR WILL BE SUFFICIENT...
THE MODEL GUIDANCE CONTINUES TO FAIL TO GIVE MUCH IN THE WAY OF
INSTABILITY. ONLY THE SW MTNS GET EVEN MINIMAL AMOUNTS OF CAPE.
THUS...SOME WIND DAMAGE POTENTIAL CANNOT BE RULED OUT ON THE TN
BORDER THROUGH THE EARLY MORNING HOURS...BUT SEVERE WEATHER LOOKS
UNLIKELY ELSEWHERE. TEMPS WILL NOT FALL OFF MUCH BEFORE THE FRONT
ARRIVES...WHICH SHOULD LEAD TO AN UNSEASONALLY MILD NIGHT OVER THE
PIEDMONT.
THE FRONT SHOULD EXIT THE WESTERN PIEDMONT BY 13Z TO 14Z. A SMALL
POP WAS KEPT OVER THE EASTERN ZONES TO START THE DAY...BUT IS
QUICKLY DISPATCHED EASTWARD. EXPECT RAPID CLEARING MONDAY MORNING
BEHIND THE FRONT...BUT COOLER AIR WILL BE SLOW TO ARRIVE. DOWNSLOPE
E OF THE MTNS WILL ALLOW TEMPS TO CLIMB ABOVE NORMAL ONCE AGAIN WITH
GUSTY NW WIND IN THE AFTERNOON.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AS OF 200 PM SUNDAY...A SPLIT QUASI-ZONAL FLOW PATTERN IS EXPECTED
IN THE UPR LVLS DURING THE SHORT TERM...WITH A SOUTHERN STREAM
SHORTWAVE TROF CROSSING THE CWFA TUESDAY NIGHT. MEANWHILE...DRY HIGH
PRES DRIFTS EAST FROM THE MIDWEST TO THE EASTERN SEABOARD BY 00Z
THURSDAY. FCST SNDGS SHOW SOME MAINLY UPR LVL MOISTURE STREAMING
ACRS THE AREA AHEAD OF THE SHORTWAVE TUESDAY EVENING. BUT IT LOOKS
VERY DRY BELOW 600 MB. SO NO PRECIP IS EXPECTED...DESPITE STRONG QG
FORCING WITH THE WAVE...JUST A PERIOD OF SOME BKN-OVC SKIES
POSSIBLE. TEMPS WILL GENERALLY BE SEVERAL DEGREES BELOW NORMAL BOTH
TUESDAY AND WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 200 EST PM SUNDAY...THE GLOBAL MODELS ARE IN FAIR AGREEMENT
WITH THE OVERALL SYNOPTIC PATTERN FOR THE MEDIUM RANGE PERIOD.
WEAK UPPER RIDGING WILL PERSIST ACROSS THE SE WED NIGHT INTO FRIDAY
AS 588 DM ANTICYCLONE BUILDS ACROSS THE GULF OF MEXICO AND SLOWLY
RETROGRADES THRU THE PERIOD. AN UPPER LOW PRESSURE TROUGH OVER SOUTH
CENTRAL CANADA ON FRI WILL THEN DIGS SOUTHEAST INTO THE GREAT LAKES
REGION FRI NIGHT...AND INTO THE SOUTHEASTERN STATES BY SAT. THE
TROUGH AXIS IS EXPECTED TO CROSS THE FORECAST AREA SUN AND OFF THE
ATLANTIC COAST BY SUN NIGHT.
AT THE SURFACE...CANADIAN HIGH PRESSURE CENTERED ACROSS NEW ENGLAND
WILL CONTINUE TO RIDGE INTO THE CWA WED NIGHT INTO
THURSDAY...ALLOWING COOL NE FLOW TO PERSIST THRU THE PERIOD. BY
FRIDAY...MOIST RETURN S/SE FLOW WILL SET UP ACROSS THE AREA AS THE
HIGH SHIFTS EAST OF THE AREA AND A COLD FRONT APPROACHES FROM THE
WEST. WITH INCREASING MOIST ISENTROPIC LIFT...POPS RAMP UP TO 20/30
PERCENT TOWARD FRI AFTERNOON. THE GFS PUSHES THE FRONT THROUGH THE
REGION FRI NIGHT INTO SAT MORNING WHILE THE SLOWER 12Z ECMWF PUSHES
IT DURING THE DAY ON SAT. BOTH THE GFS/ECMWF GENERATE ABOUT
0.25-0.5" OF QPF DURING THE FROPA. TAKING A COMPROMISE...POPS REMAIN
IN THE 30/40 PERCENT RANGE FRI NIGHT THRU EARLY SAT. CONDITIONS DRY
OUT BY SAT NIGHT AS THE FRONT PUSHES OFFSHORE AND DRY CANADIAN HIGH
BUILDS IN FROM THE WEST. TEMPERATURES WILL REMAIN 3-5 DEGREE BELOW
NORMAL THRU THURSDAY BEFORE WARMING UP TO NEAR NORMAL RANGE BY FRI.
TEMPS THEN DROP CONSIDERABLY TO 7-10 BELOW NORMAL ON SUN AS COLD
CANADIAN HIGH BUILDS IN.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
AT KCLT...AT TAF ISSUANCE...MVFR CLOUDS REMAINED ACROSS THE
TERMINAL. HOWEVER...IFR CLOUDS AND MVFR VIS WILL LIKELY SWEEP EAST
ACROSS THE TERMINAL BY 2Z...REMAINING UNTIL FROPA OCCURS AROUND
SUNRISE. ALTHOUGH TSRA MAY EXIST ALONG THE FRONT BETWEEN 9-12Z...I
WILL MENTION ONLY SHRA AT THIS TIME. CEILINGS WILL BEGIN TO LIFT AS
WINDS VEER AROUND 10Z...BECOMING VFR BY 13Z. NW WINDS EXPECTED
SHORTLY AFTER SUNRISE...VEERING TO 320 DEGREES BETWEEN 7-10 KTS BY
17Z.
ELSEWHERE...AT TAF ISSUANCE...CEILINGS AND VIS ACROSS THE WESTERN
CAROLINA TAFS RANGED FROM IFR TO LIFR. BASED ON UPSTREAM OBS...I
WOULD EXPECT THAT CONDITIONS WILL NOT VARY MUCH TONIGHT...UNTIL
FROPA OCCURS DURING THE PRE DAWN HOURS. ALTHOUGH TSRA MAY EXIST
ALONG THE FRONT...I WILL MENTION ONLY SHRA AT THIS TIME. CEILINGS
WILL BEGIN TO LIFT AS WINDS VEER AROUND 10Z...BECOMING VFR BETWEEN
11-13Z. NW WINDS EXPECTED SHORTLY AFTER SUNRISE...VEERING TO 310-330
DEGREES BETWEEN 7-10 KTS BY 17Z. KAVL MAY SEE GUSTS TO 25 MPH BY MID
DAY.
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...
02-08Z 08-14Z 14-20Z 20-02Z
KCLT HIGH 88% HIGH 81% HIGH 100% HIGH 100%
KGSP MED 75% HIGH 83% HIGH 97% HIGH 100%
KAVL HIGH 91% HIGH 86% HIGH 97% HIGH 100%
KHKY MED 74% MED 77% HIGH 97% HIGH 100%
KGMU HIGH 81% HIGH 85% HIGH 97% HIGH 100%
KAND HIGH 86% HIGH 86% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.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...JOH
NEAR TERM...NED/PM
SHORT TERM...ARK
LONG TERM...JOH
AVIATION...NED
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
715 PM EST SUN NOV 17 2013
.SYNOPSIS...
A STRONG COLD FRONT IS EXPECTED TO PUSH THROUGH THE FORECAST AREA
TONIGHT INTO EARLY MONDAY...FOLLOWED BY COLD CANADIAN HIGH PRESSURE
BUILDING OVER THE REGION THROUGH THE MIDDLE OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
AS OF 7 PM...AREAS OF RAIN AND HEAVY DRIZZLE WILL REMAIN ACROSS THE
FORECAST AREA THIS EVENING AND INTO EARLY MON MORNING. THE PRIMARY
FORECAST CONCERN WILL BE ASSOCIATED WITH THE PRE FRONTAL BAND OF
TSRA...LOCATED OVER MIDDLE AND WESTERN KY/TN. 22Z HRRR INDICATES
THAT THE BAND WILL APPROACH THE NC/TN LINE BY 7Z. THROUGH 9Z...HRRR
INDICATES THAT LINE SEGMENTS OF SHRA/TSRA WILL PUSH ACROSS THE
MTNS...TRACKING ACROSS THE NC FOOTHILLS. PRE FRONT NAM12 SHERB 0-3
KM VALUES RANGE FROM .6-.7. ALSO...0-3 KM EHI VALUES DECREASE FROM
.7-.4 M2/S2 FROM WEST TO EAST. I WOULD EXPECT THAT THE LINE OF
CONVECTION WILL CROSS THE SPINE OF THE APPALACHIANS LATE
TONIGHT...LARGELY INTACT. HOWEVER...THE ENVIRONMENT DOES NOT FAVOR
AN ORGANIZED BAND OF CONVECTION ACROSS THE THE FOOTHILLS AND
PIEDMONT. THE HWO APPEARS WELL WORDED...NO CHANGES PLANNED AT THIS
TIME. OTHERWISE...TEMPS SHOULD REMAIN NEARLY STEADY THIS EVENING AND
TONIGHT.
AS OF MID AFTERNOON...SHOWERS CONTINUE TO DEVELOP AND FILL IN ACROSS
NE GEORGIA...THE UPSTATE...AND THE NC FOOTHILLS...WHILE AN AREA OF
PRECIP MOVES ACRS THE NC MTNS FROM ERN TN. PRECIP CHANCES GRADUALLY
RAMP UP THROUGH THE REST OF THE DAYLIGHT HOURS TO ACCOUNT FOR THIS.
TEMPS ARE WARMER THAN EXPECTED ACROSS METRO CHARLOTTE...SO HIGH
TEMPS WERE RAISED THERE.
THE FIRST BATCH OF PRECIP WAS BEING DRIVEN BY THE PASSAGE OF A SHORT
WAVE...SEEN ON THE WATER VAPOR IMAGERY. THERE COULD BE A LULL IN
ACTIVITY MOVING IN FROM THE WEST THIS EVENING...ALTHO LOW LEVEL
MOISTURE AND FORCING WILL REMAIN IN PLACE. THIS DOES NOT LEAVE
ENOUGH CONFIDENCE TO TEMPORARILY LOWER THE PRECIP CHANCES AHEAD OF
THE FRONT...BUT SOME TWEAKING MIGHT BE DONE DURING THE EARLY EVENING
IF REDEVELOPMENT IS NOT SEEN. MOST SIGNS POINT TO A FRONTAL PASSAGE
DURING THE EARLY MORNING HOURS ACROSS MOST OF THE FCST AREA...WITH
THE FRONT STRETCHED OUT OVER THE PIEDMONT AT SUNRISE. THE MAIN ISSUE
IS THE SEVERE WEATHER POTENTIAL. ALTHO SHEAR WILL BE SUFFICIENT...
THE MODEL GUIDANCE CONTINUES TO FAIL TO GIVE MUCH IN THE WAY OF
INSTABILITY. ONLY THE SW MTNS GET EVEN MINIMAL AMOUNTS OF CAPE.
THUS...SOME WIND DAMAGE POTENTIAL CANNOT BE RULED OUT ON THE TN
BORDER THROUGH THE EARLY MORNING HOURS...BUT SEVERE WEATHER LOOKS
UNLIKELY ELSEWHERE. TEMPS WILL NOT FALL OFF MUCH BEFORE THE FRONT
ARRIVES...WHICH SHOULD LEAD TO AN UNSEASONALLY MILD NIGHT OVER THE
PIEDMONT.
THE FRONT SHOULD EXIT THE WESTERN PIEDMONT BY 13Z TO 14Z. A SMALL
POP WAS KEPT OVER THE EASTERN ZONES TO START THE DAY...BUT IS
QUICKLY DISPATCHED EASTWARD. EXPECT RAPID CLEARING MONDAY MORNING
BEHIND THE FRONT...BUT COOLER AIR WILL BE SLOW TO ARRIVE. DOWNSLOPE
E OF THE MTNS WILL ALLOW TEMPS TO CLIMB ABOVE NORMAL ONCE AGAIN WITH
GUSTY NW WIND IN THE AFTERNOON.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AS OF 200 PM SUNDAY...A SPLIT QUASI-ZONAL FLOW PATTERN IS EXPECTED
IN THE UPR LVLS DURING THE SHORT TERM...WITH A SOUTHERN STREAM
SHORTWAVE TROF CROSSING THE CWFA TUESDAY NIGHT. MEANWHILE...DRY HIGH
PRES DRIFTS EAST FROM THE MIDWEST TO THE EASTERN SEABOARD BY 00Z
THURSDAY. FCST SNDGS SHOW SOME MAINLY UPR LVL MOISTURE STREAMING
ACRS THE AREA AHEAD OF THE SHORTWAVE TUESDAY EVENING. BUT IT LOOKS
VERY DRY BELOW 600 MB. SO NO PRECIP IS EXPECTED...DESPITE STRONG QG
FORCING WITH THE WAVE...JUST A PERIOD OF SOME BKN-OVC SKIES
POSSIBLE. TEMPS WILL GENERALLY BE SEVERAL DEGREES BELOW NORMAL BOTH
TUESDAY AND WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 200 EST PM SUNDAY...THE GLOBAL MODELS ARE IN FAIR AGREEMENT
WITH THE OVERALL SYNOPTIC PATTERN FOR THE MEDIUM RANGE PERIOD.
WEAK UPPER RIDGING WILL PERSIST ACROSS THE SE WED NIGHT INTO FRIDAY
AS 588 DM ANTICYCLONE BUILDS ACROSS THE GULF OF MEXICO AND SLOWLY
RETROGRADES THRU THE PERIOD. AN UPPER LOW PRESSURE TROUGH OVER SOUTH
CENTRAL CANADA ON FRI WILL THEN DIGS SOUTHEAST INTO THE GREAT LAKES
REGION FRI NIGHT...AND INTO THE SOUTHEASTERN STATES BY SAT. THE
TROUGH AXIS IS EXPECTED TO CROSS THE FORECAST AREA SUN AND OFF THE
ATLANTIC COAST BY SUN NIGHT.
AT THE SURFACE...CANADIAN HIGH PRESSURE CENTERED ACROSS NEW ENGLAND
WILL CONTINUE TO RIDGE INTO THE CWA WED NIGHT INTO
THURSDAY...ALLOWING COOL NE FLOW TO PERSIST THRU THE PERIOD. BY
FRIDAY...MOIST RETURN S/SE FLOW WILL SET UP ACROSS THE AREA AS THE
HIGH SHIFTS EAST OF THE AREA AND A COLD FRONT APPROACHES FROM THE
WEST. WITH INCREASING MOIST ISENTROPIC LIFT...POPS RAMP UP TO 20/30
PERCENT TOWARD FRI AFTERNOON. THE GFS PUSHES THE FRONT THROUGH THE
REGION FRI NIGHT INTO SAT MORNING WHILE THE SLOWER 12Z ECMWF PUSHES
IT DURING THE DAY ON SAT. BOTH THE GFS/ECMWF GENERATE ABOUT
0.25-0.5" OF QPF DURING THE FROPA. TAKING A COMPROMISE...POPS REMAIN
IN THE 30/40 PERCENT RANGE FRI NIGHT THRU EARLY SAT. CONDITIONS DRY
OUT BY SAT NIGHT AS THE FRONT PUSHES OFFSHORE AND DRY CANADIAN HIGH
BUILDS IN FROM THE WEST. TEMPERATURES WILL REMAIN 3-5 DEGREE BELOW
NORMAL THRU THURSDAY BEFORE WARMING UP TO NEAR NORMAL RANGE BY FRI.
TEMPS THEN DROP CONSIDERABLY TO 7-10 BELOW NORMAL ON SUN AS COLD
CANADIAN HIGH BUILDS IN.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
AT KCLT...AT TAF ISSUANCE...MVFR CLOUDS REMAINED ACROSS THE
TERMINAL. HOWEVER...IFR CLOUDS AND MVFR VIS WILL LIKELY SWEEP EAST
ACROSS THE TERMINAL BY 2Z...REMAINING UNTIL FROPA OCCURS AROUND
SUNRISE. ALTHOUGH TSRA MAY EXIST ALONG THE FRONT BETWEEN 9-12Z...I
WILL MENTION ONLY SHRA AT THIS TIME. CEILINGS WILL BEGIN TO LIFT AS
WINDS VEER AROUND 10Z...BECOMING VFR BY 13Z. NW WINDS EXPECTED
SHORTLY AFTER SUNRISE...VEERING TO 320 DEGREES BETWEEN 7-10 KTS BY
17Z.
ELSEWHERE...AT TAF ISSUANCE...CEILINGS AND VIS ACROSS THE WESTERN
CAROLINA TAFS RANGED FROM IFR TO LIFR. BASED ON UPSTREAM OBS...I
WOULD EXPECT THAT CONDITIONS WILL NOT VARY MUCH TONIGHT...UNTIL
FROPA OCCURS DURING THE PRE DAWN HOURS. ALTHOUGH TSRA MAY EXIST
ALONG THE FRONT...I WILL MENTION ONLY SHRA AT THIS TIME. CEILINGS
WILL BEGIN TO LIFT AS WINDS VEER AROUND 10Z...BECOMING VFR BETWEEN
11-13Z. NW WINDS EXPECTED SHORTLY AFTER SUNRISE...VEERING TO 310-330
DEGREES BETWEEN 7-10 KTS BY 17Z. KAVL MAY SEE GUSTS TO 25 MPH BY MID
DAY.
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...
00-06Z 06-12Z 12-18Z 18-24Z
KCLT HIGH 93% HIGH 83% HIGH 95% HIGH 100%
KGSP MED 60% MED 79% HIGH 96% HIGH 100%
KAVL HIGH 95% HIGH 87% HIGH 95% HIGH 100%
KHKY MED 65% MED 63% HIGH 97% HIGH 100%
KGMU MED 79% HIGH 80% HIGH 96% HIGH 100%
KAND HIGH 85% HIGH 81% HIGH 95% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.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...JOH
NEAR TERM...NED/PM
SHORT TERM...ARK
LONG TERM...JOH
AVIATION...NED
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
954 AM EST SAT NOV 16 2013
.SYNOPSIS...
THE NEXT COLD FRONT IS EXPECTED TO PUSH THROUGH THE REGION SUNDAY
NIGHT INTO EARLY MONDAY...FOLLOWED BY STRONG HIGH PRESSURE BUILDING
OVER THE REGION THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF MID MORNING...THE FCST APPEARS TO BE ON TRACK. SATELLITE
IMAGERY SHOWS THE HIGH ELEVATIONS OF THE NC MTNS ALREADY POKING UP
ABOVE THE LOW CLOUDS. A FEW HOLES IN THE OVERCAST ARE STARTING TO
OPEN UP OVER THE PIEDMONT OF THE CAROLINAS...BUT THESE MIGHT FILL
BACK IN WITH CLOUDS AT LEAST TEMPORARILY. THINK IT WILL TAKE A FEW
MORE HOURS...UNTIL MIDDAY...BEFORE WHOLESALE SCATTERING OCCURS.
TEMPS ARE IN GOOD SHAPE.
PREVIOUS DISCUSSION...
AS OF 245 AM EST SATURDAY...WIDESPREAD LOW CLOUDS AND AREAS OF FOG
WILL GRADUALLY LIFT AND PARTIALLY BURN OFF THIS MORNING. SO FAR THE
FOG HAS BEEN WELL SHORT OF ADVISORY CRITERIA. WITH ALL SITES
REPORTING A CEILING AT THIS HOUR...IT WOULD APPEAR THAT ANY DENSE
FOG THROUGH MID MORNING WILL BE ISOLATED. SCATTERED PATCHES OF RAIN
CONTINUE ATTM OVER WRN NC...BUT A WEAKENING LOW LEVEL WIND FIELD AND
NVA ALOFT SHOULD BRING THAT TO AN END IN A COUPLE HOURS. OTHERWISE
IT WILL BE A QUIET WEATHER DAY AS HEIGHTS RISE OVER THE REGION AHEAD
OF STRONG TROUGH DIGGING INTO THE CENTRAL HIGH PLAINS STATES.
LOW LEVEL WINDS WILL INCREASE IN SPEED TONIGHT AHEAD OF THAT
DEEPENING TROUGH. THE NAM H8 WINDS INCREASE TO AROUND 30 KTS. THE
STRENGTHENING WINDS AND INCREASING LLVL WARM ADVECTION AS A THERMAL
RIDGE MOVES IN FROM THE WEST WILL BE SUFFICIENT FOR ANOTHER ROUND OF
UPSLOPE ENHANCED LIGHT RAIN AND DRIZZLE. THE BULK OF THE PCPN SHOULD
BE CONFINED TO THE MOUNTAINS AND WRN FOOTHILLS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AT 230 AM EST SATURDAY...AN UPPER RIDGE WILL BE OFF THE EAST COAST
ON SATURDAY...WHILE AN UPPER TROUGH WILL BE OVER THE CENTER OF THE
NATION. THE DEAMPLIFYING TROUGH AXIS WILL PROGRESS TO THE CENTRAL
AND SOUTHERN APPALACHIANS BY BY MONDAY...MOVING OFF THE EAST COAST
ON MONDAY NIGHT.
SURFACE HIGH PRESSURE WIL WEAKEN ALONG THE EAST COAST ON SUNDAY...
WHILE A COLD FRONT CROSSES THE MS RIVER VALLEY. MOIST ISENTROPIC
UPGLIDE FLOW WILL PRECEDE THE FRONT ON SUNDAY AND SUNDAY NIGHT...
HOWEVER LOW LEVEL UPSLOPE FLOW WILL WEAKEN AS WINDS VEER AND BECOME
PARALLEL TO THE BLUE RIDGE. FRONTAL PASSAGE OVER OUR AREA IS
EXPECTED TO OCCUR LATE SUNDAY NIGHT AND EARLY MONDAY. WHILE BOTH THE
NAM AND GFS SHOW SHEAR CROSSING THE AREA WITH THE FRONT...NAM CAPE
IS MARGINAL...AND GFS CAPE MUCH WEAKER. THE SITUATION WILL NEED TO
BE MONITORED FOR THE POSSIBILITY OF A LOW CAPE...HIGH SHEAR
ENVIRONMENT. PRECIPITATION IS NOT EXPECTED TO BE EXCESSIVE...WITH
PERHAPS A BIT MORE THAN ONE INCH OF RAINFALL ALONG THE SOUTH FACING
BLUE RIDGE ESCARPMENT.
TEMPERATURES WILL WARM ABOVE NORMAL AHEAD OF THE FRONT...WITH A
REDUCED DIURNAL RANGE IN CLOUDS AND PRECIPITATION. TEMPERATURES WILL
WARM EVEN FURTHER ABOVE NORMAL MONDAY IN DOWNSLOPE FLOW BEHIND THE
FRONT....BUT WILL FALL BELOW NORMAL MONDAY NIGHT IN COLD ADVECTION
WITH WINDS DIMINISHING AND VEERING.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 155 AM EST SATURDAY...TUESDAY THROUGH FRIDAY NIGHT...MEDIUM
RANGE MODELS SHOW HIGH PRESSURE CENTERED OVER ILLINOIS AT 12Z
TUESDAY WITH PRESSURE GRADIENT EASING OVER THE CAROLINAS. BY 00Z WED
THE CENTER OF THE HIGH IS OVER THE EASTERN GREAT LAKES WITH LOW
LEVEL WIND FLOW FOR OUR AREA BEING GENERALLY NE. AS THIS HIGH MOVES
OFF THE NEW ENGLAND COAST THURSDAY AFTERNOON...THE WIND FLOW BECOMES
MORE EAST TO SE AND TEMPS RISE A BIT FROM JANUARY TYPE TEMPS TO JUST
A FEW DEGREES BELOW NORMAL ON FRIDAY. THE GFS HAS A SURFACE LOW
FORMING OVER EAST TEXAS FRIDAY NIGHT AND MOVING NE WHILE THE ECMWF
HAS A LESS VIGOROUS TROUGH AND SURFACE DEVELOPMENT. BOTH OF THESE
MODELS HAVE AT LEAST SOME LIGHT PRECIP MOVING INTO THE WESTERN NC
MTNS BY LATE FRIDAY NIGHT. THEREFORE...I HAVE INTRODUCED SLIGHT POPS
FOR THAT AREA IN THE EXTRA PERIOD OF FRIDAY NIGHT.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
AT KCLT...SKIES HAVE ACTUALLY CLEARED ABOUT 20 MILES TO THE
SOUTHEAST OF THE AIRFIELD. HOWEVER...THE LLVL FLOW IS WEAKLY OUT OF
THE SOUTHWEST AND CIGS BETWEEN 005-007 SHOULD LAST THROUGH ABOUT 15
UTC. THE NAM MODEL SOUNDINGS IMPLY CONDITIONS COULD IMPROVE
EARLIER...THE RAP LATER. WITH THE VERY LIGHT LLVL WINDS AND FAIRLY
WEAK INVERSION...I DON/T SEE THE IFR LEVEL CIGS HANGING AROUND MUCH
BEYOND 15 UTC...BUT I/M NOT TERRIBLY CONFIDENT ABOUT THIS. A PERIOD
OF VFR CONDITIONS IS EXPECTED TO DEVELOP THIS AFTERNOON...WITH
STRATUS RETURNING AGAIN TONIGHT. IN FACT...WITH A STRONGER WIND
FIELD AND BETTER WARM ADVECTION...I THINK THE CHANCES OF AN IFR DECK
ARE PRETTY GOOD.
ELSEWHERE...IFR CONDITIONS PREVAIL ACROSS THE REGION THIS MORNING.
EXPECTING CIGS TO HOLD GENERALLY BETWEEN 007-010 OVER THE NEXT FEW
HOURS. HOWEVER...THERE HAVE BEEN BREAKS IN THE IFR WITH AN MVFR DECK
ABOVE THAT. ADDED A TEMPO GROUP TO ACCOUNT FOR THIS AT ALL SITES
EXCEPT KAVL. VSBYS SHOULD GENERALLY BE IN THE MVFR RANGE AT THE
UPSTATE SITES...AND A LITTLE LOWER IN NC. IT IS POSSIBLE THAT
CONDITIONS WILL WORSEN AFTER SUNRISE WITH THE MOIST LOW LEVELS. THE
LLVL WINDS LOOK TOO WEAK TO SUPPORT STRATUS...CAUSING ME TO BE
CONCERNED ABOUT INCREASING AMOUNTS OF FOG AFTER 12 UTC. I DON/T SEE
ANYTHING TO REALLY HANG MY HAT ON IN THIS REGARD...WHICH IS WHY THE
TAFS SIMPLY REFLECT THE PREVAILING CONDITIONS FOR ANOTHER 3 HOURS OR
SO. THERE SHOULD BE SOME IMPROVEMENT THIS AFTN WITH MANY AREAS
SEEING VFR CIGS. LATER SAT NIGHT AS THE LLVL WINDS AND WARM
ADVECTION INCREASE...CHANCES LOOK GOOD FOR AN IFR DECK. LIGHT RAIN
IS ALSO POSSIBLE LATE TONIGHT...ESPECIALLY AROUND KAVL.
OUTLOOK...THE APPROACH OF THE NEXT STRONG COLD FRONT WILL BRING
INCREASING RAIN CHANCES AND LIKELY RESTRICTIONS ON SUNDAY INTO EARLY
MONDAY. A RETURN TO MUCH DRIER WEATHER IS EXPECTED BY LATE MONDAY.
CONFIDENCE TABLE...
15-21Z 21-03Z 03-09Z 09-15Z
KCLT HIGH 93% HIGH 83% MED 79% MED 75%
KGSP MED 76% HIGH 90% MED 79% MED 78%
KAVL MED 65% HIGH 83% HIGH 94% HIGH 96%
KHKY MED 79% HIGH 84% HIGH 97% HIGH 100%
KGMU MED 77% HIGH 90% HIGH 81% HIGH 81%
KAND MED 79% HIGH 83% MED 77% MED 78%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...DEO
NEAR TERM...MCAVOY/PM
SHORT TERM...JAT
LONG TERM...DEO
AVIATION...MCAVOY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
641 AM EST SAT NOV 16 2013
.SYNOPSIS...
THE NEXT COLD FRONT IS EXPECTED TO PUSH THROUGH THE REGION SUNDAY
NIGHT INTO EARLY MONDAY...FOLLOWED BY STRONG HIGH PRESSURE BUILDING
OVER THE REGION THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 615 AM EST SATURDAY...UPPED MIN TEMPS A FEW DEGREES AS
WIDESPREAD LOW CLOUDS HAVE RESULTED IN NEAR STEADY TEMPS THE BEST
SEVERAL HOURS. DEWPOINTS ARE ALSO A LITTLE HIGHER THAN WHAT WAS IN
THE GRIDS AND THOSE HAVE BEEN BUMPED UP AS WELL. IT WILL BE
INTERESTING TO SEE IF FOG BECOMES MORE WIDESPREAD AFTER SUNRISE.
AS OF 245 AM EST SATURDAY...WIDESPREAD LOW CLOUDS AND AREAS OF FOG
WILL GRADUALLY LIFT AND PARTIALLY BURN OFF THIS MORNING. SO FAR THE
FOG HAS BEEN WELL SHORT OF ADVISORY CRITERIA. WITH ALL SITES
REPORTING A CEILING AT THIS HOUR...IT WOULD APPEAR THAT ANY DENSE
FOG THROUGH MID MORNING WILL BE ISOLATED. SCATTERED PATCHES OF RAIN
CONTINUE ATTM OVER WRN NC...BUT A WEAKENING LOW LEVEL WIND FIELD AND
NVA ALOFT SHOULD BRING THAT TO AN END IN A COUPLE HOURS. OTHERWISE
IT WILL BE A QUIET WEATHER DAY AS HEIGHTS RISE OVER THE REGION AHEAD
OF STRONG TROUGH DIGGING INTO THE CENTRAL HIGH PLAINS STATES.
LOW LEVEL WINDS WILL INCREASE IN SPEED TONIGHT AHEAD OF THAT
DEEPENING TROUGH. THE NAM H8 WINDS INCREASE TO AROUND 30 KTS. THE
STRENGTHENING WINDS AND INCREASING LLVL WARM ADVECTION AS A THERMAL
RIDGE MOVES IN FROM THE WEST WILL BE SUFFICIENT FOR ANOTHER ROUND OF
UPSLOPE ENHANCED LIGHT RAIN AND DRIZZLE. THE BULK OF THE PCPN SHOULD
BE CONFINED TO THE MOUNTAINS AND WRN FOOTHILLS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AT 230 AM EST SATURDAY...AN UPPER RIDGE WILL BE OFF THE EAST COAST
ON SATURDAY...WHILE AN UPPER TROUGH WILL BE OVER THE CENTER OF THE
NATION. THE DEAMPLIFYING TROUGH AXIS WILL PROGRESS TO THE CENTRAL
AND SOUTHERN APPALACHIANS BY BY MONDAY...MOVING OFF THE EAST COAST
ON MONDAY NIGHT.
SURFACE HIGH PRESSURE WIL WEAKEN ALONG THE EAST COAST ON SUNDAY...
WHILE A COLD FRONT CROSSES THE MS RIVER VALLEY. MOIST ISENTROPIC
UPGLIDE FLOW WILL PRECEDE THE FRONT ON SUNDAY AND SUNDAY NIGHT...
HOWEVER LOW LEVEL UPSLOPE FLOW WILL WEAKEN AS WINDS VEER AND BECOME
PARALLEL TO THE BLUE RIDGE. FRONTAL PASSAGE OVER OUR AREA IS
EXPECTED TO OCCUR LATE SUNDAY NIGHT AND EARLY MONDAY. WHILE BOTH THE
NAM AND GFS SHOW SHEAR CROSSING THE AREA WITH THE FRONT...NAM CAPE
IS MARGINAL...AND GFS CAPE MUCH WEAKER. THE SITUATION WILL NEED TO
BE MONITORED FOR THE POSSIBILITY OF A LOW CAPE...HIGH SHEAR
ENVIRONMENT. PRECIPITATION IS NOT EXPECTED TO BE EXCESSIVE...WITH
PERHAPS A BIT MORE THAN ONE INCH OF RAINFALL ALONG THE SOUTH FACING
BLUE RIDGE ESCARPMENT.
TEMPERATURES WILL WARM ABOVE NORMAL AHEAD OF THE FRONT...WITH A
REDUCED DIURNAL RANGE IN CLOUDS AND PRECIPITATION. TEMPERATURES WILL
WARM EVEN FURTHER ABOVE NORMAL MONDAY IN DOWNSLOPE FLOW BEHIND THE
FRONT....BUT WILL FALL BELOW NORMAL MONDAY NIGHT IN COLD ADVECTION
WITH WINDS DIMINISHING AND VEERING.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 155 AM EST SATURDAY...TUESDAY THROUGH FRIDAY NIGHT...MEDIUM
RANGE MODELS SHOW HIGH PRESSURE CENTERED OVER ILLINOIS AT 12Z
TUESDAY WITH PRESSURE GRADIENT EASING OVER THE CAROLINAS. BY 00Z WED
THE CENTER OF THE HIGH IS OVER THE EASTERN GREAT LAKES WITH LOW
LEVEL WIND FLOW FOR OUR AREA BEING GENERALLY NE. AS THIS HIGH MOVES
OFF THE NEW ENGLAND COAST THURSDAY AFTERNOON...THE WIND FLOW BECOMES
MORE EAST TO SE AND TEMPS RISE A BIT FROM JANUARY TYPE TEMPS TO JUST
A FEW DEGREES BELOW NORMAL ON FRIDAY. THE GFS HAS A SURFACE LOW
FORMING OVER EAST TEXAS FRIDAY NIGHT AND MOVING NE WHILE THE ECMWF
HAS A LESS VIGOROUS TROUGH AND SURFACE DEVELOPMENT. BOTH OF THESE
MODELS HAVE AT LEAST SOME LIGHT PRECIP MOVING INTO THE WESTERN NC
MTNS BY LATE FRIDAY NIGHT. THEREFORE...I HAVE INTRODUCED SLIGHT POPS
FOR THAT AREA IN THE EXTRA PERIOD OF FRIDAY NIGHT.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
AT KCLT...SKIES HAVE ACTUALLY CLEARED ABOUT 20 MILES TO THE
SOUTHEAST OF THE AIRFIELD. HOWEVER...THE LLVL FLOW IS WEAKLY OUT OF
THE SOUTHWEST AND CIGS BETWEEN 005-007 SHOULD LAST THROUGH ABOUT 15
UTC. THE NAM MODEL SOUNDINGS IMPLY CONDITIONS COULD IMPROVE
EARLIER...THE RAP LATER. WITH THE VERY LIGHT LLVL WINDS AND FAIRLY
WEAK INVERSION...I DON/T SEE THE IFR LEVEL CIGS HANGING AROUND MUCH
BEYOND 15 UTC...BUT I/M NOT TERRIBLY CONFIDENT ABOUT THIS. A PERIOD
OF VFR CONDITIONS IS EXPECTED TO DEVELOP THIS AFTERNOON...WITH
STRATUS RETURNING AGAIN TONIGHT. IN FACT...WITH A STRONGER WIND
FIELD AND BETTER WARM ADVECTION...I THINK THE CHANCES OF AN IFR DECK
ARE PRETTY GOOD.
ELSEWHERE...IFR CONDITIONS PREVAIL ACROSS THE REGION THIS MORNING.
EXPECTING CIGS TO HOLD GENERALLY BETWEEN 007-010 OVER THE NEXT FEW
HOURS. HOWEVER...THERE HAVE BEEN BREAKS IN THE IFR WITH AN MVFR DECK
ABOVE THAT. ADDED A TEMPO GROUP TO ACCOUNT FOR THIS AT ALL SITES
EXCEPT KAVL. VSBYS SHOULD GENERALLY BE IN THE MVFR RANGE AT THE
UPSTATE SITES...AND A LITTLE LOWER IN NC. IT IS POSSIBLE THAT
CONDITIONS WILL WORSEN AFTER SUNRISE WITH THE MOIST LOW LEVELS. THE
LLVL WINDS LOOK TOO WEAK TO SUPPORT STRATUS...CAUSING ME TO BE
CONCERNED ABOUT INCREASING AMOUNTS OF FOG AFTER 12 UTC. I DON/T SEE
ANYTHING TO REALLY HANG MY HAT ON IN THIS REGARD...WHICH IS WHY THE
TAFS SIMPLY REFLECT THE PREVAILING CONDITIONS FOR ANOTHER 3 HOURS OR
SO. THERE SHOULD BE SOME IMPROVEMENT THIS AFTN WITH MANY AREAS
SEEING VFR CIGS. LATER SAT NIGHT AS THE LLVL WINDS AND WARM
ADVECTION INCREASE...CHANCES LOOK GOOD FOR AN IFR DECK. LIGHT RAIN
IS ALSO POSSIBLE LATE TONIGHT...ESPECIALLY AROUND KAVL.
OUTLOOK...THE APPROACH OF THE NEXT STRONG COLD FRONT WILL BRING
INCREASING RAIN CHANCES AND LIKELY RESTRICTIONS ON SUNDAY INTO EARLY
MONDAY. A RETURN TO MUCH DRIER WEATHER IS EXPECTED BY LATE MONDAY.
CONFIDENCE TABLE...
11-17Z 17-23Z 23-05Z 05-11Z
KCLT MED 74% HIGH 92% HIGH 87% MED 73%
KGSP MED 62% HIGH 88% MED 71% HIGH 82%
KAVL MED 66% MED 79% MED 75% HIGH 93%
KHKY LOW 55% HIGH 86% HIGH 83% HIGH 95%
KGMU MED 61% HIGH 88% MED 68% HIGH 80%
KAND LOW 55% HIGH 85% MED 71% MED 73%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...DEO
NEAR TERM...MCAVOY
SHORT TERM...JAT
LONG TERM...DEO
AVIATION...MCAVOY
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1157 AM CST SAT NOV 16 2013
.UPDATE...
18Z AVIATION DISCUSSION UPDATED BELOW.
FOG IS STILL PRESENT ACROSS PARTS OF NORTHEAST SOUTH DAKOTA AND
WEST CENTRAL MINNESOTA. THE KATY OB HAS IMPROVED FROM A QUARTER
MILE VISIBILITY UP TO A HALF...BUT WITHOUT ANYTHING TO SCOUR OUT
THE LOW LEVEL MOISTURE...LEFT THE FOG MENTION IN THROUGH THE EARLY
AFTERNOON HOURS. A NARROW AREA OF SPRINKLES HAS DEVELOPED ALONG A
LINE FROM EUREKA TO BOWDLE TO HOVEN...SO ADDED THIS MENTION INTO
THE FORECAST...AND ADJUSTED THE TIMING OF POPS MOVING INTO
NORTHEAST SOUTH DAKOTA TO MATCH CURRENT RADAR TRENDS.
OTHERWISE...THE OVERALL FORECAST REMAINS ON TRACK THIS MORNING.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TODAY THROUGH MONDAY
WEAK UPPER LEVEL DISTURBANCE DRIFTING NORTHEAST ACROSS THE AREA
EARLY THIS MORNING. WEAK LIFT SLIDING THROUGH AND FOG SATELLITE
SHOWING SOME TEXTURE TO THE MID LEVEL DECK MOVING NORTHEAST
THROUGH THE CWA. RADAR HAS SOME VERY LIGHT RETURNS WITHIN THE MID
LEVEL DECK......MAYBE JUST A COUPLE SPRINKLES. MAIN THING TO
WATCH TODAY IS THE SECONDARY WAVE WHICH IS A TAD FURTHER
SOUTH...AND ITS EXPECTED DEVELOPMENT OF SHOWERS ACROSS SOUTHEAST
SOUTH DAKOTA INTO MINNESOTA. EVEN THIS CLOSE TO EVENT
TIME...MODELS STILL HAVING A TOUGH TIME DETERMINING PLACEMENT OF
PRECIP AND THE HANDLING OF THE STRATUS DECK WELL TO THE SOUTH. NO
SIGN OF STRATUS ANYWHERE NEAR THE CWA...WITH THINGS RIGHT NOW
PUSHED WELL SOUTH INTO KANSAS AND MISSOURI. ALTHOUGH...MODELS
STILL SUGGESTING SOME DEVELOPMENT SHORTLY AFTER 12Z. VERY LOW
CONFIDENCE IN JUST HOW FAST STRATUS MAKES IT INTO SOUTHEAST SOUTH
DAKOTA AND THE SOUTHEAST CWA. FOR RIGHT NOW HAVE CONSTRUCTED SKY
GRIDS TO SHOW SOME INCREASE IN CLOUDS LATER THIS MORNING. FEEL
THERE WILL BE AT LEAST SOME DEVELOPMENT OF STRATUS BY LATER TODAY.
REMOVED DRIZZLE FROM THE FORECAST AS SOUNDINGS OVER THE SOUTHEAST
CWA JUST DO NOT SUPPORT IT. NO DEEP MOISTURE LAYER DOWN LOW AT
ALL. BETTER SIGNAL SHOWS UP CLOSE TO SIOUX FALLS AREA. WILL LEAVE
IN 20 POPS ACROSS THE FAR EASTERN CWA TO SORT OF GO ALONG WITH
WHAT THE HRRR AND ABR 4KM MODELS ARE SHOWING. AT THIS POINT...NOT
REALLY BUYING INTO THE MORE QPF-HAPPY EC AND GFS WHICH HAS PRECIP
BACK FURTHER WEST INTO THE JAMES VALLEY WITHIN A STRATUS DECK.
ATTENTION THEN TURNS TO THE STRONGER UPPER LEVEL SHORTWAVE ENERGY
MOVING ACROSS THE DAKOTAS LATE TONIGHT THROUGH SUNDAY. MODELS
CONTINUE TO WARM THE LOWER LEVELS OF THE ATMOSPHERE AND HAVE
INCREASED HIGHS ON SUNDAY. NOW IT APPEARS MOST OF TONIGHT WILL BE
DRY WITH CHANCES MOVING INTO THE WESTERN CWA BY 12Z SUNDAY. LEFT
PRECIP MOSTLY RAIN THOUGH AS THERMAL PROFILES STILL FAIRLY MILD
THROUGH THE NIGHT. AROUND 12Z SUNDAY AND SHORTLY AFTER THE COLUMN
BEGINS TO COOL ENOUGH TO SUPPORT MAINLY SNOWFALL DURING THE
MORNING HOURS...BUT WARMING AGAIN DURING THE AFTERNOON. MODELS
HAVING A TOUGH TIME WITH THIS SHORTWAVE ENERGY AS WELL IN REGARDS
TO PRECIP PLACEMENT. OVERALL...A FAIRLY LOW CONFIDENCE FORECAST
UNFORTUNATELY. BUT HAVING SAID THAT...IT DOES APPEAR THE BEST
CHANCE FOR PRECIP IN THE SHORT TERM WILL BE WITH WHATEVER
MATERIALIZES WITHIN THE UPPER LEVEL SHORTWAVE ENERGY LATER TONIGHT
THROUGH SUNDAY. ALSO NEED TO MENTION THE WINDS ON SUNDAY AS THEY
WILL GET RATHER GUSTY WITHIN A TIGHTENING PRESSURE GRADIENT. COULD
BE LOOKING AT WIND ADVISORY SPEEDS OVER THE WESTERN CWA ON SUNDAY.
WILL CONTINUE TO MONITOR.
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY
SEEMS THE GLOBAL SPECTRAL MODELS ARE CONTINUING TO HAVE A TOUGH
TIME RESOLVING FLOW PATTERN EVOLUTION AND SHORT-WAVE TIMING IN THE
FARTHER OUT FORECAST TIME PERIODS. FOR THE PAST COUPLE OF MORNINGS
THE GFS AND ECMWF HAVE BEEN HINTING AT THE DEVELOPMENT OF A PERIOD
OF SPLIT FLOW IN THE OUT PERIODS. MODELS ARE KNOWN TO HAVE
DIFFICULTIES RESOLVING FLOW PATTERN FEATURES IN THE SHORTER RANGE
FORECAST PERIODS /CONSIDERABLY LOWER FORECAST CONFIDENCE/ WHEN A
SPLIT FLOW PATTERN IS OCCURRING OR IMMINENT...LET ALONE THE LONGER
RANGE FORECAST TIME-FRAME. SO IT WOULD BE SAFE TO SAY...FORECASTER
CONFIDENCE IN LONGER RANGE SOLUTIONS IS LOWER THAN NORMAL.
THE ECMWF STILL HAS A STRONG COLD FRONT WORKING THROUGH THE REGION
BY THE MIDDLE OF NEXT WEEK. IT DOES NOT HAVE A BAND OF SNOW
WORKING ACROSS THE CWA...THOUGH...FOR WEDNESDAY NIGHT. THAT
FEATURE HAS SLOWED BY ABOUT 12 HOURS AND IS FURTHER SOUTH NOW
ACROSS NEBRASKA. THE GFS COLD FRONTAL FEATURE STILL SEEMS TO LAG
BEHIND THE ECMWF BY ABOUT 12 HOURS...WHILE THE GEM REMAINS APPX 12
HOURS FASTER THAN THE ECMWF. SO...WITH FRONTAL TIMING DIFFERENCES
STILL ABOUNDING...AND PRECIPITATION TIMING/PLACEMENT FORECASTS
STILL EVOLVING...SEEMS LIKE GOING AS DRY AS POSSIBLE FOR AS MUCH
OF THE LONG TERM AS POSSIBLE IS A GOOD MOVE THIS MORNING. AT THIS
POINT...THURSDAY STILL LOOKS LIKE THE COLDEST DAY OF THE
EXTENDED...ALTHOUGH THAT WILL PROBABLY CHANGE BY TOMORROW
MORNING...AS WELL.
&&
.AVIATION...
18Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
ONE UPPER LEVEL LOW PRESSURE SYSTEM WAS LEAVING THE EASTERN PART
OF THE REGION THIS AFTERNOON WHILE ANOTHER STRONGER SYSTEM WAS
MOVING IN FROM THE NORTHWEST. THE LOW STRATUS AND FOG AT ATY IS
EXPECTED TO BREAK UP/LIFT THROUGH THE AFTERNOON...POSSIBLY
REFORMING AGAIN TONIGHT. AT THIS TIME...LEFT IT OUT OF ATY FOR
TONIGHT AND WILL HAVE TO WATCH. OTHERWISE...AS THE MID AND HIGH
LEVEL CLOUDS EXIT WITH THE FIRST SYSTEM MORE VFR CLOUDS WILL
SPREAD IN WITH THE NEXT SYSTEM. SOME SCATTERED LIGHT RAIN SHOWERS
WILL ALSO SPREAD IN FOR LATER TONIGHT AND SUNDAY MORNING POSSIBLY
AFFECTING THE TERMINALS WITH NO REDUCTION IN VISIBILITY EXPECTED.
MAY HAVE TO INSERT IN TERMINALS AS WE GET CLOSER. NORTHWEST WINDS
ARE EXPECTED TO ALSO PICK UP ON SUNDAY MORNING.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...SERR
SHORT TERM...TMT
LONG TERM...DORN
AVIATION...MOHR
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1041 AM CST SAT NOV 16 2013
.UPDATE...
FOG IS STILL PRESENT ACROSS PARTS OF NORTHEAST SOUTH DAKOTA AND
WEST CENTRAL MINNESOTA. THE KATY OB HAS IMPROVED FROM A QUARTER
MILE VISIBILITY UP TO A HALF...BUT WITHOUT ANYTHING TO SCOUR OUT
THE LOW LEVEL MOISTURE...LEFT THE FOG MENTION IN THROUGH THE EARLY
AFTERNOON HOURS. A NARROW AREA OF SPRINKLES HAS DEVELOPED ALONG A
LINE FROM EUREKA TO BOWDLE TO HOVEN...SO ADDED THIS MENTION INTO
THE FORECAST...AND ADJUSTED THE TIMING OF POPS MOVING INTO
NORTHEAST SOUTH DAKOTA TO MATCH CURRENT RADAR TRENDS.
OTHERWISE...THE OVERALL FORECAST REMAINS ON TRACK THIS MORNING.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TODAY THROUGH MONDAY
WEAK UPPER LEVEL DISTURBANCE DRIFTING NORTHEAST ACROSS THE AREA
EARLY THIS MORNING. WEAK LIFT SLIDING THROUGH AND FOG SATELLITE
SHOWING SOME TEXTURE TO THE MID LEVEL DECK MOVING NORTHEAST
THROUGH THE CWA. RADAR HAS SOME VERY LIGHT RETURNS WITHIN THE MID
LEVEL DECK......MAYBE JUST A COUPLE SPRINKLES. MAIN THING TO
WATCH TODAY IS THE SECONDARY WAVE WHICH IS A TAD FURTHER
SOUTH...AND ITS EXPECTED DEVELOPMENT OF SHOWERS ACROSS SOUTHEAST
SOUTH DAKOTA INTO MINNESOTA. EVEN THIS CLOSE TO EVENT
TIME...MODELS STILL HAVING A TOUGH TIME DETERMINING PLACEMENT OF
PRECIP AND THE HANDLING OF THE STRATUS DECK WELL TO THE SOUTH. NO
SIGN OF STRATUS ANYWHERE NEAR THE CWA...WITH THINGS RIGHT NOW
PUSHED WELL SOUTH INTO KANSAS AND MISSOURI. ALTHOUGH...MODELS
STILL SUGGESTING SOME DEVELOPMENT SHORTLY AFTER 12Z. VERY LOW
CONFIDENCE IN JUST HOW FAST STRATUS MAKES IT INTO SOUTHEAST SOUTH
DAKOTA AND THE SOUTHEAST CWA. FOR RIGHT NOW HAVE CONSTRUCTED SKY
GRIDS TO SHOW SOME INCREASE IN CLOUDS LATER THIS MORNING. FEEL
THERE WILL BE AT LEAST SOME DEVELOPMENT OF STRATUS BY LATER TODAY.
REMOVED DRIZZLE FROM THE FORECAST AS SOUNDINGS OVER THE SOUTHEAST
CWA JUST DO NOT SUPPORT IT. NO DEEP MOISTURE LAYER DOWN LOW AT
ALL. BETTER SIGNAL SHOWS UP CLOSE TO SIOUX FALLS AREA. WILL LEAVE
IN 20 POPS ACROSS THE FAR EASTERN CWA TO SORT OF GO ALONG WITH
WHAT THE HRRR AND ABR 4KM MODELS ARE SHOWING. AT THIS POINT...NOT
REALLY BUYING INTO THE MORE QPF-HAPPY EC AND GFS WHICH HAS PRECIP
BACK FURTHER WEST INTO THE JAMES VALLEY WITHIN A STRATUS DECK.
ATTENTION THEN TURNS TO THE STRONGER UPPER LEVEL SHORTWAVE ENERGY
MOVING ACROSS THE DAKOTAS LATE TONIGHT THROUGH SUNDAY. MODELS
CONTINUE TO WARM THE LOWER LEVELS OF THE ATMOSPHERE AND HAVE
INCREASED HIGHS ON SUNDAY. NOW IT APPEARS MOST OF TONIGHT WILL BE
DRY WITH CHANCES MOVING INTO THE WESTERN CWA BY 12Z SUNDAY. LEFT
PRECIP MOSTLY RAIN THOUGH AS THERMAL PROFILES STILL FAIRLY MILD
THROUGH THE NIGHT. AROUND 12Z SUNDAY AND SHORTLY AFTER THE COLUMN
BEGINS TO COOL ENOUGH TO SUPPORT MAINLY SNOWFALL DURING THE
MORNING HOURS...BUT WARMING AGAIN DURING THE AFTERNOON. MODELS
HAVING A TOUGH TIME WITH THIS SHORTWAVE ENERGY AS WELL IN REGARDS
TO PRECIP PLACEMENT. OVERALL...A FAIRLY LOW CONFIDENCE FORECAST
UNFORTUNATELY. BUT HAVING SAID THAT...IT DOES APPEAR THE BEST
CHANCE FOR PRECIP IN THE SHORT TERM WILL BE WITH WHATEVER
MATERIALIZES WITHIN THE UPPER LEVEL SHORTWAVE ENERGY LATER TONIGHT
THROUGH SUNDAY. ALSO NEED TO MENTION THE WINDS ON SUNDAY AS THEY
WILL GET RATHER GUSTY WITHIN A TIGHTENING PRESSURE GRADIENT. COULD
BE LOOKING AT WIND ADVISORY SPEEDS OVER THE WESTERN CWA ON SUNDAY.
WILL CONTINUE TO MONITOR.
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY
SEEMS THE GLOBAL SPECTRAL MODELS ARE CONTINUING TO HAVE A TOUGH
TIME RESOLVING FLOW PATTERN EVOLUTION AND SHORT-WAVE TIMING IN THE
FARTHER OUT FORECAST TIME PERIODS. FOR THE PAST COUPLE OF MORNINGS
THE GFS AND ECMWF HAVE BEEN HINTING AT THE DEVELOPMENT OF A PERIOD
OF SPLIT FLOW IN THE OUT PERIODS. MODELS ARE KNOWN TO HAVE
DIFFICULTIES RESOLVING FLOW PATTERN FEATURES IN THE SHORTER RANGE
FORECAST PERIODS /CONSIDERABLY LOWER FORECAST CONFIDENCE/ WHEN A
SPLIT FLOW PATTERN IS OCCURRING OR IMMINENT...LET ALONE THE LONGER
RANGE FORECAST TIME-FRAME. SO IT WOULD BE SAFE TO SAY...FORECASTER
CONFIDENCE IN LONGER RANGE SOLUTIONS IS LOWER THAN NORMAL.
THE ECMWF STILL HAS A STRONG COLD FRONT WORKING THROUGH THE REGION
BY THE MIDDLE OF NEXT WEEK. IT DOES NOT HAVE A BAND OF SNOW
WORKING ACROSS THE CWA...THOUGH...FOR WEDNESDAY NIGHT. THAT
FEATURE HAS SLOWED BY ABOUT 12 HOURS AND IS FURTHER SOUTH NOW
ACROSS NEBRASKA. THE GFS COLD FRONTAL FEATURE STILL SEEMS TO LAG
BEHIND THE ECMWF BY ABOUT 12 HOURS...WHILE THE GEM REMAINS APPX 12
HOURS FASTER THAN THE ECMWF. SO...WITH FRONTAL TIMING DIFFERENCES
STILL ABOUNDING...AND PRECIPITATION TIMING/PLACEMENT FORECASTS
STILL EVOLVING...SEEMS LIKE GOING AS DRY AS POSSIBLE FOR AS MUCH
OF THE LONG TERM AS POSSIBLE IS A GOOD MOVE THIS MORNING. AT THIS
POINT...THURSDAY STILL LOOKS LIKE THE COLDEST DAY OF THE
EXTENDED...ALTHOUGH THAT WILL PROBABLY CHANGE BY TOMORROW
MORNING...AS WELL.
&&
.AVIATION...
12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
VFR SHOULD PREVAIL TODAY AND TONIGHT AT KMBG...KPIR AND KABR.
THERE MAY BE A COUPLE SPRINKLES OR FLURRIES AT KPIR AND KABR AND
ALONG A LINE BETWEEN THESE TWO TERMINALS THROUGH ABOUT MID-DAY
TODAY. BUT...THIS SHOULD NOT IMPACT CIGS OR VISBIES.
KATY CONTINUES TO REMAIN THE CONCERN FOR SUB-VFR CONDITIONS.
SURFACE TO TOP-OF-THE-BOUNDARY-LAYER MOISTURE CONTINUES TO
INCREASE THIS MORNING ON LIGHT SOUTH WINDS. UPSTREAM FROM
KATY...SITES ACROSS SERN SOUTH DAKOTA AND SWRN MINNESOTA ARE
REPORTING IFR CIGS AND IN SOME CASES MVFR/IFR VISBIES. SEEMS
INCREASINGLY PROBABLE THAT KATY WILL BE DOWN INTO SOME FORM OF
SUB-VFR FLYING CONDITIONS WITHIN THE NEXT 3 TO 6 HOURS. THERE IS
ALSO A CHANCE FOR SOME RAIN AT KATY MAINLY LATER THIS AFTERNOON
FOR A FEW HOURS AS A LOW PRESSURE SYSTEM LIFTS NEWD ACROSS THE
REGION.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...SERR
SHORT TERM...TMT
LONG TERM...DORN
AVIATION...DORN
WEATHER.GOV/ABERDEEN
SEE BELOW FOR AN UPDATED AVIATION FORECAST DISCUSSION.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TODAY THROUGH MONDAY
WEAK UPPER LEVEL DISTURBANCE DRIFTING NORTHEAST ACROSS THE AREA
EARLY THIS MORNING. WEAK LIFT SLIDING THROUGH AND FOG SATELLITE
SHOWING SOME TEXTURE TO THE MID LEVEL DECK MOVING NORTHEAST
THROUGH THE CWA. RADAR HAS SOME VERY LIGHT RETURNS WITHIN THE MID
LEVEL DECK......MAYBE JUST A COUPLE SPRINKLES. MAIN THING TO
WATCH TODAY IS THE SECONDARY WAVE WHICH IS A TAD FURTHER
SOUTH...AND ITS EXPECTED DEVELOPMENT OF SHOWERS ACROSS SOUTHEAST
SOUTH DAKOTA INTO MINNESOTA. EVEN THIS CLOSE TO EVENT
TIME...MODELS STILL HAVING A TOUGH TIME DETERMINING PLACEMENT OF
PRECIP AND THE HANDLING OF THE STRATUS DECK WELL TO THE SOUTH. NO
SIGN OF STRATUS ANYWHERE NEAR THE CWA...WITH THINGS RIGHT NOW
PUSHED WELL SOUTH INTO KANSAS AND MISSOURI. ALTHOUGH...MODELS
STILL SUGGESTING SOME DEVELOPMENT SHORTLY AFTER 12Z. VERY LOW
CONFIDENCE IN JUST HOW FAST STRATUS MAKES IT INTO SOUTHEAST SOUTH
DAKOTA AND THE SOUTHEAST CWA. FOR RIGHT NOW HAVE CONSTRUCTED SKY
GRIDS TO SHOW SOME INCREASE IN CLOUDS LATER THIS MORNING. FEEL
THERE WILL BE AT LEAST SOME DEVELOPMENT OF STRATUS BY LATER TODAY.
REMOVED DRIZZLE FROM THE FORECAST AS SOUNDINGS OVER THE SOUTHEAST
CWA JUST DO NOT SUPPORT IT. NO DEEP MOISTURE LAYER DOWN LOW AT
ALL. BETTER SIGNAL SHOWS UP CLOSE TO SIOUX FALLS AREA. WILL LEAVE
IN 20 POPS ACROSS THE FAR EASTERN CWA TO SORT OF GO ALONG WITH
WHAT THE HRRR AND ABR 4KM MODELS ARE SHOWING. AT THIS POINT...NOT
REALLY BUYING INTO THE MORE QPF-HAPPY EC AND GFS WHICH HAS PRECIP
BACK FURTHER WEST INTO THE JAMES VALLEY WITHIN A STRATUS DECK.
ATTENTION THEN TURNS TO THE STRONGER UPPER LEVEL SHORTWAVE ENERGY
MOVING ACROSS THE DAKOTAS LATE TONIGHT THROUGH SUNDAY. MODELS
CONTINUE TO WARM THE LOWER LEVELS OF THE ATMOSPHERE AND HAVE
INCREASED HIGHS ON SUNDAY. NOW IT APPEARS MOST OF TONIGHT WILL BE
DRY WITH CHANCES MOVING INTO THE WESTERN CWA BY 12Z SUNDAY. LEFT
PRECIP MOSTLY RAIN THOUGH AS THERMAL PROFILES STILL FAIRLY MILD
THROUGH THE NIGHT. AROUND 12Z SUNDAY AND SHORTLY AFTER THE COLUMN
BEGINS TO COOL ENOUGH TO SUPPORT MAINLY SNOWFALL DURING THE
MORNING HOURS...BUT WARMING AGAIN DURING THE AFTERNOON. MODELS
HAVING A TOUGH TIME WITH THIS SHORTWAVE ENERGY AS WELL IN REGARDS
TO PRECIP PLACEMENT. OVERALL...A FAIRLY LOW CONFIDENCE FORECAST
UNFORTUNATELY. BUT HAVING SAID THAT...IT DOES APPEAR THE BEST
CHANCE FOR PRECIP IN THE SHORT TERM WILL BE WITH WHATEVER
MATERIALIZES WITHIN THE UPPER LEVEL SHORTWAVE ENERGY LATER TONIGHT
THROUGH SUNDAY. ALSO NEED TO MENTION THE WINDS ON SUNDAY AS THEY
WILL GET RATHER GUSTY WITHIN A TIGHTENING PRESSURE GRADIENT. COULD
BE LOOKING AT WIND ADVISORY SPEEDS OVER THE WESTERN CWA ON SUNDAY.
WILL CONTINUE TO MONITOR.
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY
SEEMS THE GLOBAL SPECTRAL MODELS ARE CONTINUING TO HAVE A TOUGH
TIME RESOLVING FLOW PATTERN EVOLUTION AND SHORT-WAVE TIMING IN THE
FARTHER OUT FORECAST TIME PERIODS. FOR THE PAST COUPLE OF MORNINGS
THE GFS AND ECMWF HAVE BEEN HINTING AT THE DEVELOPMENT OF A PERIOD
OF SPLIT FLOW IN THE OUT PERIODS. MODELS ARE KNOWN TO HAVE
DIFFICULTIES RESOLVING FLOW PATTERN FEATURES IN THE SHORTER RANGE
FORECAST PERIODS /CONSIDERABLY LOWER FORECAST CONFIDENCE/ WHEN A
SPLIT FLOW PATTERN IS OCCURRING OR IMMINENT...LET ALONE THE LONGER
RANGE FORECAST TIME-FRAME. SO IT WOULD BE SAFE TO SAY...FORECASTER
CONFIDENCE IN LONGER RANGE SOLUTIONS IS LOWER THAN NORMAL.
THE ECMWF STILL HAS A STRONG COLD FRONT WORKING THROUGH THE REGION
BY THE MIDDLE OF NEXT WEEK. IT DOES NOT HAVE A BAND OF SNOW
WORKING ACROSS THE CWA...THOUGH...FOR WEDNESDAY NIGHT. THAT
FEATURE HAS SLOWED BY ABOUT 12 HOURS AND IS FURTHER SOUTH NOW
ACROSS NEBRASKA. THE GFS COLD FRONTAL FEATURE STILL SEEMS TO LAG
BEHIND THE ECMWF BY ABOUT 12 HOURS...WHILE THE GEM REMAINS APPX 12
HOURS FASTER THAN THE ECMWF. SO...WITH FRONTAL TIMING DIFFERENCES
STILL ABOUNDING...AND PRECIPITATION TIMING/PLACEMENT FORECASTS
STILL EVOLVING...SEEMS LIKE GOING AS DRY AS POSSIBLE FOR AS MUCH
OF THE LONG TERM AS POSSIBLE IS A GOOD MOVE THIS MORNING. AT THIS
POINT...THURSDAY STILL LOOKS LIKE THE COLDEST DAY OF THE
EXTENDED...ALTHOUGH THAT WILL PROBABLY CHANGE BY TOMORROW
MORNING...AS WELL.
&&
.AVIATION...
12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
VFR SHOULD PREVAIL TODAY AND TONIGHT AT KMBG...KPIR AND KABR.
THERE MAY BE A COUPLE SPRINKLES OR FLURRIES AT KPIR AND KABR AND
ALONG A LINE BETWEEN THESE TWO TERMINALS THROUGH ABOUT MID-DAY
TODAY. BUT...THIS SHOULD NOT IMPACT CIGS OR VISBIES.
KATY CONTINUES TO REMAIN THE CONCERN FOR SUB-VFR CONDITIONS.
SURFACE TO TOP-OF-THE-BOUNDARY-LAYER MOISTURE CONTINUES TO
INCREASE THIS MORNING ON LIGHT SOUTH WINDS. UPSTREAM FROM
KATY...SITES ACROSS SERN SOUTH DAKOTA AND SWRN MINNESOTA ARE
REPORTING IFR CIGS AND IN SOME CASES MVFR/IFR VISBIES. SEEMS
INCREASINGLY PROBABLE THAT KATY WILL BE DOWN INTO SOME FORM OF
SUB-VFR FLYING CONDITIONS WITHIN THE NEXT 3 TO 6 HOURS. THERE IS
ALSO A CHANCE FOR SOME RAIN AT KATY MAINLY LATER THIS AFTERNOON
FOR A FEW HOURS AS A LOW PRESSURE SYSTEM LIFTS NEWD ACROSS THE
REGION.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...DORN
SHORT TERM...TMT
LONG TERM...DORN
AVIATION...DORN
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
332 AM CST SAT NOV 16 2013
.SHORT TERM...TODAY THROUGH MONDAY
WEAK UPPER LEVEL DISTURBANCE DRIFTING NORTHEAST ACROSS THE AREA
EARLY THIS MORNING. WEAK LIFT SLIDING THROUGH AND FOG SATELLITE
SHOWING SOME TEXTURE TO THE MID LEVEL DECK MOVING NORTHEAST
THROUGH THE CWA. RADAR HAS SOME VERY LIGHT RETURNS WITHIN THE MID
LEVEL DECK......MAYBE JUST A COUPLE SPRINKLES. MAIN THING TO
WATCH TODAY IS THE SECONDARY WAVE WHICH IS A TAD FURTHER
SOUTH...AND ITS EXPECTED DEVELOPMENT OF SHOWERS ACROSS SOUTHEAST
SOUTH DAKOTA INTO MINNESOTA. EVEN THIS CLOSE TO EVENT
TIME...MODELS STILL HAVING A TOUGH TIME DETERMINING PLACEMENT OF
PRECIP AND THE HANDLING OF THE STRATUS DECK WELL TO THE SOUTH. NO
SIGN OF STRATUS ANYWHERE NEAR THE CWA...WITH THINGS RIGHT NOW
PUSHED WELL SOUTH INTO KANSAS AND MISSOURI. ALTHOUGH...MODELS
STILL SUGGESTING SOME DEVELOPMENT SHORTLY AFTER 12Z. VERY LOW
CONFIDENCE IN JUST HOW FAST STRATUS MAKES IT INTO SOUTHEAST SOUTH
DAKOTA AND THE SOUTHEAST CWA. FOR RIGHT NOW HAVE CONSTRUCTED SKY
GRIDS TO SHOW SOME INCREASE IN CLOUDS LATER THIS MORNING. FEEL
THERE WILL BE AT LEAST SOME DEVELOPMENT OF STRATUS BY LATER TODAY.
REMOVED DRIZZLE FROM THE FORECAST AS SOUNDINGS OVER THE SOUTHEAST
CWA JUST DO NOT SUPPORT IT. NO DEEP MOISTURE LAYER DOWN LOW AT
ALL. BETTER SIGNAL SHOWS UP CLOSE TO SIOUX FALLS AREA. WILL LEAVE
IN 20 POPS ACROSS THE FAR EASTERN CWA TO SORT OF GO ALONG WITH
WHAT THE HRRR AND ABR 4KM MODELS ARE SHOWING. AT THIS POINT...NOT
REALLY BUYING INTO THE MORE QPF-HAPPY EC AND GFS WHICH HAS PRECIP
BACK FURTHER WEST INTO THE JAMES VALLEY WITHIN A STRATUS DECK.
ATTENTION THEN TURNS TO THE STRONGER UPPER LEVEL SHORTWAVE ENERGY
MOVING ACROSS THE DAKOTAS LATE TONIGHT THROUGH SUNDAY. MODELS
CONTINUE TO WARM THE LOWER LEVELS OF THE ATMOSPHERE AND HAVE
INCREASED HIGHS ON SUNDAY. NOW IT APPEARS MOST OF TONIGHT WILL BE
DRY WITH CHANCES MOVING INTO THE WESTERN CWA BY 12Z SUNDAY. LEFT
PRECIP MOSTLY RAIN THOUGH AS THERMAL PROFILES STILL FAIRLY MILD
THROUGH THE NIGHT. AROUND 12Z SUNDAY AND SHORTLY AFTER THE COLUMN
BEGINS TO COOL ENOUGH TO SUPPORT MAINLY SNOWFALL DURING THE
MORNING HOURS...BUT WARMING AGAIN DURING THE AFTERNOON. MODELS
HAVING A TOUGH TIME WITH THIS SHORTWAVE ENERGY AS WELL IN REGARDS
TO PRECIP PLACEMENT. OVERALL...A FAIRLY LOW CONFIDENCE FORECAST
UNFORTUNATELY. BUT HAVING SAID THAT...IT DOES APPEAR THE BEST
CHANCE FOR PRECIP IN THE SHORT TERM WILL BE WITH WHATEVER
MATERIALIZES WITHIN THE UPPER LEVEL SHORTWAVE ENERGY LATER TONIGHT
THROUGH SUNDAY. ALSO NEED TO MENTION THE WINDS ON SUNDAY AS THEY
WILL GET RATHER GUSTY WITHIN A TIGHTENING PRESSURE GRADIENT. COULD
BE LOOKING AT WIND ADVISORY SPEEDS OVER THE WESTERN CWA ON SUNDAY.
WILL CONTINUE TO MONITOR.
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY
SEEMS THE GLOBAL SPECTRAL MODELS ARE CONTINUING TO HAVE A TOUGH
TIME RESOLVING FLOW PATTERN EVOLUTION AND SHORT-WAVE TIMING IN THE
FARTHER OUT FORECAST TIME PERIODS. FOR THE PAST COUPLE OF MORNINGS
THE GFS AND ECMWF HAVE BEEN HINTING AT THE DEVELOPMENT OF A PERIOD
OF SPLIT FLOW IN THE OUT PERIODS. MODELS ARE KNOWN TO HAVE
DIFFICULTIES RESOLVING FLOW PATTERN FEATURES IN THE SHORTER RANGE
FORECAST PERIODS /CONSIDERABLY LOWER FORECAST CONFIDENCE/ WHEN A
SPLIT FLOW PATTERN IS OCCURRING OR IMMINENT...LET ALONE THE LONGER
RANGE FORECAST TIME-FRAME. SO IT WOULD BE SAFE TO SAY...FORECASTER
CONFIDENCE IN LONGER RANGE SOLUTIONS IS LOWER THAN NORMAL.
THE ECMWF STILL HAS A STRONG COLD FRONT WORKING THROUGH THE REGION
BY THE MIDDLE OF NEXT WEEK. IT DOES NOT HAVE A BAND OF SNOW
WORKING ACROSS THE CWA...THOUGH...FOR WEDNESDAY NIGHT. THAT
FEATURE HAS SLOWED BY ABOUT 12 HOURS AND IS FURTHER SOUTH NOW
ACROSS NEBRASKA. THE GFS COLD FRONTAL FEATURE STILL SEEMS TO LAG
BEHIND THE ECMWF BY ABOUT 12 HOURS...WHILE THE GEM REMAINS APPX 12
HOURS FASTER THAN THE ECMWF. SO...WITH FRONTAL TIMING DIFFERENCES
STILL ABOUNDING...AND PRECIPITATION TIMING/PLACEMENT FORECASTS
STILL EVOLVING...SEEMS LIKE GOING AS DRY AS POSSIBLE FOR AS MUCH
OF THE LONG TERM AS POSSIBLE IS A GOOD MOVE THIS MORNING. AT THIS
POINT...THURSDAY STILL LOOKS LIKE THE COLDEST DAY OF THE
EXTENDED...ALTHOUGH THAT WILL PROBABLY CHANGE BY TOMORROW
MORNING...AS WELL.
&&
.AVIATION...
06Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
VFR CONDITIONS ARE EXPECTED AT ALL TERMINALS THROUGH TONIGHT.
HOWEVER THERE IS ONE CAVEAT. SOME NEW SREF MEMBERS CONTINUE TO
BRING LOW CIGS/VSBYS NORTH TO NEAR KATY LATE TNT. THEREFORE WILL
PUT IN A MENTION OF IFR/MVFR CIGS LATE TNT AND SATURDAY MORNING
FOR KATY.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
SHORT TERM...TMT
LONG TERM...DORN
AVIATION...TDK
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
917 PM CST SUN NOV 17 2013
.DISCUSSION...
LINE OF SHOWERS AND ISOLATED THUNDERSTORMS CONTINUES TO PUSH SOUTH
INTO NORTH MISSISSIPPI. SKIES ARE CLOUDY ALONG AND AHEAD OF THIS
LINE BUT BEHIND THE LINE SKIES ARE CLEAR. TEMPERATURES RANGE FROM
THE UPPER 50S TO LOWER 70S. THE LINE OF SHOWERS SHOULD MOVE
THROUGH THE REMAINDER OF THE FORECAST AREA BY MIDNIGHT. HAVE
ADJUSTED POPS FOR THE EVENING HOURS. ALSO REMOVED MENTION OF FOG
OVERNIGHT AND INTO MONDAY MORNING.
ARS
&&
.PREV DISCUSSION... /ISSUED 542 PM CST SUN NOV 17 2013/
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...
00Z TAF CYCLE (18/00Z-19/00Z)
A COLD FRONT WILL CONTINUE EASTWARD THROUGH THE MIDSOUTH THIS
EVENING. A LINE OF SHOWERS AND EMBEDDED THUNDERSTORMS WILL MOVE
THROUGH KMKL BY 01Z WITH SHOWERS POSSIBLY DEVELOPING NEAR KTUP
UNTIL ABOUT 03Z. CONVECTION HAS ALREADY MOVED EAST OF KJBR AND IS
EXPECTED TO REMAIN NORTH AND EAST OF KMEM. MVFR CEILINGS MAY ALSO
OCCUR AT KTUP AND KMKL UNTIL FRONTAL PASSAGE. OTHERWISE VFR
CONDITIONS WITH CLEARING SKIES WILL OCCUR ACROSS THE MIDSOUTH
THROUGH THE PERIOD. WINDS TONIGHT BECOMING NW-N 6-8 KTS. WINDS
MONDAY N 9-10 KTS.
JCL
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 49 63 41 59 / 60 0 0 0
MKL 43 62 35 57 / 60 0 0 0
JBR 43 61 36 55 / 10 0 0 0
TUP 48 66 38 60 / 70 0 0 0
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
855 PM EST SUN NOV 17 2013
.DISCUSSION...
CURRENT SURFACE ANALYSIS SHOWS A COLD FRONT STRETCHING GENERALLY
ALONG A LINE FROM NEAR CINCINNATI TO NEAR NASHVILLE AND MEMPHIS. AN
UNSEASONABLY WARM AIR MASS WAS LINGERING OVER THE FORECAST AREA...
WITH DEWPOINTS CURRENTLY IN THE UPPER 50S TO MID 60S. CURRENT LAPS
DATA AND LATEST RUC MODEL RUN INDICATES A STABLE AIR MASS OVER THE
FORECAST AREA...SO EXPECT THE CONVECTIVE LINE ALONG THE COLD FRONT
TO WEAKEN AS IT MOVES EAST THIS EVENING. HOWEVER...A STRONG 850 MB
JET (WITH WINDS AROUND 60 KT) WAS STILL LOCATED OVER EASTERN KY AND
WESTERN WV...WITH THE TAIL END OF THIS LOW-LEVEL JET PROGGED TO
SWING OVER SOUTHWEST VA AND NORTHEAST TN THIS EVENING. THUS...IT
APPEARS THAT A FEW STORMS WITH DAMAGING WINDS WILL BE POSSIBLE THIS
EVENING.
OVERALL...FORECAST FOR TONIGHT APPEARS TO BE ON TRACK...BUT HAVE
ALREADY UPDATED THIS EVENING TO MENTION THE SEVERE TSTORM WATCH
UNTIL 1 AM EST.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 52 65 37 56 35 / 90 10 0 0 0
KNOXVILLE AIRPORT, TN 48 63 34 52 33 / 90 10 0 0 0
OAK RIDGE, TN 47 62 34 52 33 / 90 10 0 0 0
TRI CITIES AIRPORT, TN 46 60 31 49 28 / 90 10 0 0 0
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...WIND ADVISORY UNTIL 4 AM EST /3 AM CST/ MONDAY FOR THE FOLLOWING
ZONES: BLEDSOE...BLOUNT SMOKY MOUNTAINS...COCKE SMOKY
MOUNTAINS...JOHNSON...MARION...MORGAN...SCOTT TN...
SEQUATCHIE...SEVIER SMOKY MOUNTAINS...SOUTHEAST CARTER...
SOUTHEAST GREENE...SOUTHEAST MONROE...UNICOI.
VA...WIND ADVISORY UNTIL 4 AM EST MONDAY FOR THE FOLLOWING ZONES:
LEE...RUSSELL...SCOTT...WASHINGTON...WISE.
&&
$$
DMG
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
542 PM CST SUN NOV 17 2013
.UPDATE...
UPDATED TO INCLUDE THE 00Z AVIATION DISCUSSION BELOW.
JCL
&&
.DISCUSSION... /ISSUED 205 PM CST SUN NOV 17 2013/
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...
00Z TAF CYCLE (18/00Z-19/00Z)
A COLD FRONT WILL CONTINUE EASTWARD THROUGH THE MIDSOUTH THIS
EVENING. A LINE OF SHOWERS AND EMBEDDED THUNDERSTORMS WILL MOVE
THROUGH KMKL BY 01Z WITH SHOWERS POSSIBLY DEVELOPING NEAR KTUP
UNTIL ABOUT 03Z. CONVECTION HAS ALREADY MOVED EAST OF KJBR AND IS
EXPECTED TO REMAIN NORTH AND EAST OF KMEM. MVFR CEILINGS MAY ALSO
OCCUR AT KTUP AND KMKL UNTIL FRONTAL PASSAGE. OTHERWISE VFR
CONDITIONS WITH CLEARING SKIES WILL OCCUR ACROSS THE MIDSOUTH
THROUGH THE PERIOD. WINDS TONIGHT BECOMING NW-N 6-8 KTS. WINDS
MONDAY N 9-10 KTS.
JCL
&&
.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...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
533 AM CST SAT NOV 16 2013
.DISCUSSION...
SEE THE 12Z AVIATION DISCUSSION BELOW.
40
&&
.AVIATION...
DIFFICULT FORECAST. MVFR TO IFR SHOULD IMPROVE SLOWLY THROUGH THE
MID AND LATE MORNING. ISOLATED SHOWERS WERE DEVELOPING OVER THE
GULF WATERS SOUTH OF FREEPORT...HOWEVER THE MODEL SOUNDINGS
INDICATE A CAP WILL BE IN PLACE AND DO NOT EXPECT THESE TO BECOME
MORE WIDESPREAD. AS THE CEILINGS LIFT...BREEZY CONDITIONS MAY
DEVELOP THIS AFTERNOON. ANOTHER ROUND OF AT LEAST MVFR TONIGHT.
40
&&
.PREV DISCUSSION... /ISSUED 402 AM CST SAT NOV 16 2013/
DISCUSSION...
PATCHY FOG...LOCALLY DENSE IN A FEW SPOTS...WILL PERSIST THROUGH
MID MORNING BEFORE ERODING. DEEP MOISTURE REMAINS IN PLACE. NOT
MUCH IN THE WAY OF A LOW LEVEL FOCUS AND UPPER LEVEL SUPPORT BUT
THE MOISTURE LEVELS ARE SO HIGH THAT FEEL SOME SHOWERS WILL
DEVELOP DURING THE DAY. BOTH THE RAP AND TEXAS TECH WRF SHOW
SHOWERS DEVELOPING THIS AFTN SO WILL ADD 20 POPS BACK TO THE
FCST. OVERNIGHT LOWS ON SUN MORNING WILL BE UNSEASONABLY WARM AND
MINS WILL ONLY FALL INTO THE UPPER 60S. W-SW WINDS JUST OFF THE
SURFACE COUPLED WITH THE WARM START SHOULD YIELD MAX TEMPS IN THE
MID 80S. RECORD HIGH TEMPERATURES ARE POSSIBLE ON SUNDAY. FCST
SOUNDINGS ON SUNDAY SHOW AN ERODING CAP AND PWATS BETWEEN 1.6 AND
1.8 INCHES SO WILL MAINTAIN 20 POPS ON SUNDAY.
A COLD FRONT WILL CROSS SE TX ON MONDAY. GFS LOOKS A BIT FAST WITH
THIS FEATURE AND PREFER THE SLOWER NAM/ECMWF SOLN. MSTR POOLS
AHEAD OF THE BOUNDARY AND SCT SHRA/TSRA WILL BE POSSIBLE ALONG THE
COAST AND PARTS OF THE SOUTHERN CWA. AM CARRYING CHC POPS FOR THE
COAST ON MONDAY MORNING BUT FEEL THESE MIGHT BE A TAD LOW. MSTR
LEVELS NEVER REALLY DROP OFF THIS WEEK AND AN UPPER LEVEL
DISTURBANCE COULD BRING MORE SHOWERS ON TUESDAY AFTN. SW FLOW
ALOFT ON THURSDAY WILL BRING A DISTURBANCE ACROSS SE TX. THIS
FEATURE COUPLED WITH PWATS AROUND 1.6 INCHES SHOULD AGAIN YIELD
MORE PRECIP. MSTR ON THE BACKSIDE OF A RETREATING SURFACE RIDGE
WILL CONTINUE TO DRAW DEEPER MSTR INTO SE TX THU/FRI. A COLD FRONT
WILL CROSS SE TX ON FRI AND RAIN CHANCES WILL CONTINUE. A DEEP
UPPER LEVEL LOW WILL REMAIN WEST OF THE REGION THROUGH NEXT
WEEKEND. ISENTROPIC UPGLIDE WILL BE MAXIMIZED WITH NNE SFC WINDS
BEING OVERRUN BY SW WINDS ALOFT. NEXT WEEKEND LOOKS RAINY AND
KIND OF RAW. MAX TEMPS WILL STRUGGLE TO REACH 50 DEGREES IF THE
ECMWF VERIFIES. LEANED TOWARD THE ECMWF NEXT FRI-SUN BUT MODELS
DIFFER WITH TIMING AND RUN TO RUN CONSISTENCY HAS BEEN POOR. 43
CLIMATE...
RECORD HIGH TEMPERATURES ARE POSSIBLE ON SUNDAY. RECORDS FOR
SUNDAY NOV 17TH ARE THE FOLLOWING:
CURRENT RECORDS FORECAST
VALUES
IAH 84 - 1985 86
CLL 85 - 1921 86
MARINE...
LONG PERIOD SWELLS WERE OCCURRING AT BUOY 42019. MAY NEED TO UPGRADE
TO A SMALL CRAFT ADVISORY IF THESE CONTINUE AND WILL UPDATE IF
NEEDED. OTHERWISE...WINDS WILL GRADUALLY DECREASE LATER TODAY AND
TONIGHT AS A COLD FRONT MOVES TOWARD THE COAST. THE FRONT IS
EXPECTED TO PUSH OFF THE COAST MONDAY MORNING WITH INITIAL POST
FRONTAL WINDS OUT OF THE NORTH. THE MODELS ARE CONSISTENT WITH
MODERATE TO STRONG NORTHEAST WINDS DEVELOP MONDAY NIGHT AND TUESDAY.
AS HIGH PRESSURE MOVES ACROSS THE LOWER MISSISSIPPI VALLEY INTO THE
EASTERN SEABOARD...EXPECT SOUTHEAST WINDS TO DEVELOP BY WEDNESDAY.
40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 81 71 86 61 74 / 20 20 20 10 10
HOUSTON (IAH) 81 72 86 66 77 / 20 20 20 20 20
GALVESTON (GLS) 77 70 78 69 74 / 20 20 20 30 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 9 AM CST THIS MORNING FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT 20 TO 60 NM.
&&
$$
DISCUSSION...43
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
402 AM CST SAT NOV 16 2013
.DISCUSSION...
PATCHY FOG...LOCALLY DENSE IN A FEW SPOTS...WILL PERSIST THROUGH
MID MORNING BEFORE ERODING. DEEP MOISTURE REMAINS IN PLACE. NOT
MUCH IN THE WAY OF A LOW LEVEL FOCUS AND UPPER LEVEL SUPPORT BUT
THE MOISTURE LEVELS ARE SO HIGH THAT FEEL SOME SHOWERS WILL
DEVELOP DURING THE DAY. BOTH THE RAP AND TEXAS TECH WRF SHOW
SHOWERS DEVELOPING THIS AFTN SO WILL ADD 20 POPS BACK TO THE
FCST. OVERNIGHT LOWS ON SUN MORNING WILL BE UNSEASONABLY WARM AND
MINS WILL ONLY FALL INTO THE UPPER 60S. W-SW WINDS JUST OFF THE
SURFACE COUPLED WITH THE WARM START SHOULD YIELD MAX TEMPS IN THE
MID 80S. RECORD HIGH TEMPERATURES ARE POSSIBLE ON SUNDAY. FCST
SOUNDINGS ON SUNDAY SHOW AN ERODING CAP AND PWATS BETWEEN 1.6 AND
1.8 INCHES SO WILL MAINTAIN 20 POPS ON SUNDAY.
A COLD FRONT WILL CROSS SE TX ON MONDAY. GFS LOOKS A BIT FAST WITH
THIS FEATURE AND PREFER THE SLOWER NAM/ECMWF SOLN. MSTR POOLS
AHEAD OF THE BOUNDARY AND SCT SHRA/TSRA WILL BE POSSIBLE ALONG THE
COAST AND PARTS OF THE SOUTHERN CWA. AM CARRYING CHC POPS FOR THE
COAST ON MONDAY MORNING BUT FEEL THESE MIGHT BE A TAD LOW. MSTR
LEVELS NEVER REALLY DROP OFF THIS WEEK AND AN UPPER LEVEL
DISTURBANCE COULD BRING MORE SHOWERS ON TUESDAY AFTN. SW FLOW
ALOFT ON THURSDAY WILL BRING A DISTURBANCE ACROSS SE TX. THIS
FEATURE COUPLED WITH PWATS AROUND 1.6 INCHES SHOULD AGAIN YIELD
MORE PRECIP. MSTR ON THE BACKSIDE OF A RETREATING SURFACE RIDGE
WILL CONTINUE TO DRAW DEEPER MSTR INTO SE TX THU/FRI. A COLD FRONT
WILL CROSS SE TX ON FRI AND RAIN CHANCES WILL CONTINUE. A DEEP
UPPER LEVEL LOW WILL REMAIN WEST OF THE REGION THROUGH NEXT
WEEKEND. ISENTROPIC UPGLIDE WILL BE MAXIMIZED WITH NNE SFC WINDS
BEING OVERRUN BY SW WINDS ALOFT. NEXT WEEKEND LOOKS RAINY AND
KIND OF RAW. MAX TEMPS WILL STRUGGLE TO REACH 50 DEGREES IF THE
ECMWF VERIFIES. LEANED TOWARD THE ECMWF NEXT FRI-SUN BUT MODELS
DIFFER WITH TIMING AND RUN TO RUN CONSISTENCY HAS BEEN POOR. 43
&&
.CLIMATE...
RECORD HIGH TEMPERATURES ARE POSSIBLE ON SUNDAY. RECORDS FOR
SUNDAY NOV 17TH ARE THE FOLLOWING:
CURRENT RECORDS FORECAST
VALUES
IAH 84 - 1985 86
CLL 85 - 1921 86
&&
.MARINE...
LONG PERIOD SWELLS WERE OCCURRING AT BUOY 42019. MAY NEED TO UPGRADE
TO A SMALL CRAFT ADVISORY IF THESE CONTINUE AND WILL UPDATE IF
NEEDED. OTHERWISE...WINDS WILL GRADUALLY DECREASE LATER TODAY AND
TONIGHT AS A COLD FRONT MOVES TOWARD THE COAST. THE FRONT IS
EXPECTED TO PUSH OFF THE COAST MONDAY MORNING WITH INITIAL POST
FRONTAL WINDS OUT OF THE NORTH. THE MODELS ARE CONSISTENT WITH
MODERATE TO STRONG NORTHEAST WINDS DEVELOP MONDAY NIGHT AND TUESDAY.
AS HIGH PRESSURE MOVES ACROSS THE LOWER MISSISSIPPI VALLEY INTO THE
EASTERN SEABOARD...EXPECT SOUTHEAST WINDS TO DEVELOP BY WEDNESDAY.
40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 81 71 86 61 74 / 20 20 20 10 10
HOUSTON (IAH) 81 72 86 66 77 / 20 20 20 20 20
GALVESTON (GLS) 77 70 78 69 74 / 20 20 20 30 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
1131 PM CST FRI NOV 15 2013
.AVIATION...
FOR THE 06Z TAFS...PRIMARY CONCERNS REMAIN THE SMALL POTENTIAL FOR
SHRA THROUGH 12Z...AND THE WINDS AFTER 12Z. THE THREAT FOR SHRA
APPEARS TO BE LIMITED TO JUST KAMA...PRIMARILY BETWEEN 09 AND 11Z.
THE EARLIER CONCERNS FOR DOWNBURSTS WITH SHRA AND VIRGA HAVE
DECREASED AS AN INVERSION HAS DEVELOPED...AND DEW POINT DEPRESSIONS
ARE MUCH SMALLER NOW. THUS...FEW IMPACTS ARE EXPECTED FROM ANY
SHOWERS.
WINDS STILL EXPECTED TO INCREASE DRAMATICALLY BETWEEN 15 AND 18Z. KAMA
AND KDHT SHOULD SEE WIND SPEEDS APPROACH 30G40KT THROUGH LATE
AFTERNOON. WILL WAIT ONE MORE TAF ISSUANCE BEFORE DECIDING ON AN AWW
AT KAMA...THOUGH AT THIS POINT...IT APPEARS LIKELY TO BE NEEDED.
STILL A SMALL THREAT THAT WITH THE STRONGEST WINDS BLOWING DUST COULD
REDUCE VISIBILITIES INTO THE MVFR RANGE. OTHERWISE...VFR CONDITIONS
ARE EXPECTED THROUGH THE TAF PERIOD.
JOHNSON
&&
.PREV DISCUSSION... /ISSUED 518 PM CST FRI NOV 15 2013/
AVIATION...
FOR THE 00Z TAFS...THE PRIMARY CONCERNS ARE THE POTENTIAL FOR SHRA
TONIGHT...AND WINDS TOMORROW. SHRA WILL BE POSSIBLE AFTER
03Z...THOUGH MORE LIKELY AFTER 06Z...ACROSS THE W AND S TX PANHANDLE.
COVERAGE WILL BE LIMITED...SO THERE IS NOT ENOUGH CONFIDENCE TO
INCLUDE ANYTHING MORE THAN VCSH AT THIS TIME. HOWEVER...IF A SHRA
DOES DIRECTLY IMPACT A TERMINAL...GIVEN VERY DRY LOW LEVELS...THERE
IS A THREAT FOR DRY DOWNBURSTS LEADING TO GUSTY AND VARIABLE WINDS.
TOMORROW...WINDS WILL INCREASE SHORTLY AFTER 15Z...APPROACHING
30G40KT. HOWEVER...THERE IS ONE CONCERN THAT CLOUDS WILL NOT CLEAR
OUT IN TIME TO ALLOW MAXIMUM MIXING. EVEN GRANTING THE CLOUDS ARE
SLOWER TO CLEAR OUT...AGREE WITH THE PREVIOUS SHIFT THAT A FEW GUSTS
NEAR 40KT ARE LIKELY AT KAMA AND KDHT. FOR NOW HOWEVER...WILL NOT
ISSUE AN AWW FOR THE WINDS TOMORROW IN CASE AN AWW WILL BE NEEDED
THIS EVENING DUE TO THE GUSTY WINDS WITH SHRA.
VFR CONDITIONS ARE EXPECTED WITH THE EXCEPTION OF A SMALL THREAT OF
DECREASED VISIBILITIES DUE TO BLOWING DUST IN THE STRONGEST WINDS.
JOHNSON
PREV DISCUSSION... /ISSUED 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
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
16/02
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1015 AM PST Sat Nov 16 2013
.SYNOPSIS...
Low pressure will continue to bring rain and snow snow showers
across Inland Northwest today. Accumulating snow are expected
in the mountains, as well as some northern valley location. A
shower threat will linger into Sunday and early Monday. A much
wetter, but warmer system moves into the area late Monday. It
impacts will continue Tuesday and Wednesday.
&&
.DISCUSSION...
Morning update: low pressure/inverted surface trough will continue
to migrate across the region this morning and afternoon, weakening
as it does. This will keep scattered to locally numerous rain and
snow showers alive across the eastern third of WA/north ID. The
west to northwest flow will continue to focus some of the higher
snow amounts toward the ID mountains through tonight. Some brief
moderate to heavy snow showers will also be possible in some of
the heavier bands around the northeast WA mtns, the Blues and
Camas Prairie through this afternoon. Thus winter storm warnings
will continue through tonight over ID, while advisories will
linger over the northeast WA mtns, Blues and Camas Prairie through
afternoon...largely above about 2000 to 3500 feet.
I removed the advisory from the Okanogan Highlands, where shower
coverage is winding down to mainly isolated. I also let the
advisory around the COE zone expire; though some snow showers will
continue through the afternoon they will be mixed with rain as
temperatures are warming above freezing and this should limit the
amount of accumulation.
I did continue the winter weather advisory for the Cascade crest.
A look at webcams, especially around Stevens Pass, indicates some
unpleasant conditions. The HRRR also indicates some moderate bands
of snow continue in this region through at least this afternoon.
We will have to watch trends to see if this needs to be extended
longer. /J. Cote`
&&
.AVIATION...
18Z TAFS: low pressure over eastern WA/north ID will continue to
focus MVFR/lcl IFR cigs and vis with scattered rain and snow
showers around KGEG-KCOE and KPUW, especially before evening. A
period of VFR conditions is possible this afternoon, with breezy
conditions, before cigs drop toward MVFR/lcl IFR after 03-08Z
tonight through Sunday. A threat of showers will be also found
near KLWS through early evening. Toward Sunday morning a small
shower near KEAT as the next system approaches. /J. Cote`
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 38 27 41 31 42 35 / 20 10 40 40 30 60
Coeur d`Alene 38 26 39 29 41 34 / 40 20 50 50 30 60
Pullman 38 29 41 32 44 34 / 50 10 30 30 10 40
Lewiston 41 34 46 34 47 37 / 40 20 30 20 10 40
Colville 40 21 39 27 42 32 / 20 20 50 50 40 70
Sandpoint 38 25 38 30 40 33 / 60 40 60 70 50 60
Kellogg 34 28 36 27 39 34 / 70 70 50 60 20 50
Moses Lake 47 29 49 32 47 34 / 10 0 10 10 20 60
Wenatchee 45 32 45 33 46 35 / 10 0 10 10 20 60
Omak 42 27 41 30 43 33 / 10 0 30 20 30 70
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 4 AM PST Sunday for Central Panhandle
Mountains-Northern Panhandle.
Winter Weather Advisory until 4 PM PST this afternoon for Lewis
and Southern Nez Perce Counties.
WA...Winter Weather Advisory until 4 PM PST this afternoon for East
Slopes Northern Cascades-Northeast Blue Mountains.
Winter Weather Advisory until 4 PM PST this afternoon for
Northeast Mountains.
&&
$$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
927 PM PST Fri Nov 15 2013
.SYNOPSIS...
A strong weather system will spread rain and snow into most of the
region tonight and Saturday with accumulating snow in the
mountains as well as some northern valley locations. The weather
will trend slightly drier on Sunday into early Monday...except
near the Canadian border. A much wetter but warmer weather system
will move into the area late Monday and continue through Tuesday
and Wednesday.
&&
.DISCUSSION...
Looking at recent HRRR runs and some other later model guidance
felt it appropriate to delay the start of the wind advisory a few
hours to 10 PM PST rather than its earlier 7 PM start as the jet
is just a bit slow entering the area. /Pelatti
&&
.AVIATION...
06Z TAFs: Low pressure system dragging wet cold front through and
leaving a cold conditionally unstable airmass behind allow for a wet
and cluttered forecast with nuisance snow levels near elevations of
aviation sites. Thus the nuisance snowfall allows for low ceilings
and visibilities tonight and into tomorrow. Wind with the cold
front could cause nuisance low level wind shear at times as well and
allow for some gusty conditions at locations that mix these winds
down to the surface. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 33 36 27 40 31 42 / 100 60 10 40 40 10
Coeur d`Alene 33 36 25 38 29 41 / 100 90 20 50 50 20
Pullman 33 37 30 40 32 43 / 100 90 10 40 40 30
Lewiston 38 40 34 46 34 47 / 90 80 20 30 30 20
Colville 34 38 21 37 27 41 / 100 60 20 50 60 20
Sandpoint 33 36 24 37 30 40 / 100 100 40 70 70 50
Kellogg 31 33 26 35 27 39 / 100 100 70 50 60 40
Moses Lake 37 45 29 47 32 47 / 40 10 0 10 10 10
Wenatchee 35 43 30 43 33 46 / 10 10 0 10 10 10
Omak 30 40 26 39 30 43 / 20 10 0 30 20 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Weather Advisory until 10 AM PST Saturday for Coeur
d`Alene Area.
Winter Storm Warning until 4 AM PST Sunday for Central Panhandle
Mountains-Northern Panhandle.
Winter Weather Advisory until 4 PM PST Saturday for Lewis and
Southern Nez Perce Counties.
WA...Winter Weather Advisory until 4 PM PST Saturday for Northeast
Mountains-Okanogan Highlands.
Wind Advisory from 10 PM this evening to 7 AM PST Saturday for
Lower Garfield and Asotin Counties-Upper Columbia Basin-
Washington Palouse.
Winter Weather Advisory until 4 PM PST Saturday for Northeast
Blue Mountains.
&&
$$
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
358 AM EST MON NOV 18 2013
.DISCUSSION...
CURRENT...LATEST RUC ANALYSIS SHOWS A FRONTAL TROF EXTENDING FROM
THE LWR MS VALLEY UP THE APPALACHIAN RANGE PRESSING E/SE. AHEAD OF
THE FRONT...A POCKET OF MID LVL VORTICITY IS HUGGING THE N GULF
COAST...COUPLED WITH A CORRESPONDING AREA OF LIFTING OMEGA AND UPR
LVL DIVERGENCE. IR SAT PICS SHOWING SOME ENHANCED CLOUD TOPS WITH
THIS FEATURE...THOUGH KTLH-KMOB WSR-88D RADARS ONLY INDICATING
AREAS OF LIGHT TO MODERATE RAIN. WEAK H100-H70 RIDGE AXIS BISECTING
THE FL PENINSULA TOPPED BY AN H85-H50 ANTICYCLONE OVER THE CENTRAL
GOMEX. EVENING RAOB SOUNDINGS WERE ON THE MOIST SIDE WITH PWAT
VALUES BTWN 1.7"-1.8"...THOUGH ONLY KJAX SHOWED ANY DEFINITIVE
CONCENTRATION OF LOW LVL MOISTURE.
TODAY-TONIGHT...
THE FRONTAL TROF WILL COLLAPSE THE WRN FLANK OF THE LOW LVL RIDGE AS
A STRONG STORM SYSTEM OVER THE GREAT LAKES REGION PULLS THE COLD
FRONT INTO THE FL PANHANDLE. DESPITE A STRONG NW PUSH BEHIND THE
FRONT...THE MID LVL ANTICYCLONE WILL SLOW ITS ADVANCEMENT AND KEEP
IT AS THE PRIMARY WX FEATURE TO START THE WEEK. THE LCL AIRMASS WILL
BECOME SATURATED AS THE PREFRONTAL MOISTURE BAND SLIPS ITS WAY INTO
CENTRAL FL. HOWEVER...THERE IS LIMITED AVAILABLE ENERGY UPSTREAM...
MOST OF WHICH IS CONFINED TO THE WRN GOMEX ON THE FAR SIDE OF THE
AFOREMENTIONED ANTICYCLONE.
THE POSITION OF THE MID LVL ANTICYCLONE WILL BLOCK OUT WHAT LITTLE
MOST OF WHAT LITTLE MID/UPPER LVL ENERGY IS AVAILABLE. MEANWHILE...
AS THE GREAT LAKES STORM SYSTEM LIFT INTO ERN CANADA...IT WILL TAKE
MOST OF ITS TORQUE WITH IT...LEAVING THE SRN EXTENSION OF ITS
FRONTAL TROF ON ITS OWN TO PUSH INTO CENTRAL FL. THE FROPA WILL BE
QUITE SLOW...ESPECIALLY WITH WITH ZONAL FLOW ALOFT. NEVERTHELESS...
IT WILL PROVIDE SUFFICIENT LOW LVL CONVERGENCE AND DEEP ENOUGH
MOISTURE TO GENERATE A RESPECTABLE CHANCE FOR PRECIP ACRS THE CWA.
EVEN SO...WITH SUCH WEAK THERMODYNAMIC/DYNAMIC PROFILES...MOST OF
THE PRECIP WITH THIS SYSTEM WILL BE LIGHT WITH MAX QPF VALUES BTWN
0.10"-0.25" OVER MOST OF THE CWA THRU DAYBREAK TUE.
DESPITE CONSIDERABLE CLOUD COVER...THE S/SW FLOW WILL GENERATE WARM
TEMPS ACRS THE CENTRAL PENINSULA WITH MOST AREAS CLIMBING INTO THE
L/M80S...5-9C ABV AVG. WEAK PGRAD WILL PREVAIL...SHOULD SEE AN EAST
COAST SEA BREEZE DEVELOP BY EARLY AFTERNOON FROM THE CAPE ESPECIALLY
IF CLOUD COVER IS SLOW TO PUSH S. CONTINENTAL WIND COMPONENT WILL BE
BRIEF AND LIMITED TO THE OVERNIGHT PD. COUPLED WITH THE BLANKET
EFFECT OF THE PREFRONTAL CLOUD BAND...MIN TEMPS TONIGHT NOT EXPECTED
TO DROP MUCH BLO THE M60S...7-12F ABV AVG.
TUE-TUE NIGHT...
SOUTHERN END OF FRONTAL BOUNDARY WILL BECOME ORIENTED WEST-EAST
AS IT SAGS INTO THE AREA. WHILE THE FLOW ALOFT IS ZONAL AND NO
IMPULSES ARE NOTED...LOW LEVEL MOISTURE CONVERGENCE LOOKS QUITE
IMPRESSIVE FOR THIS TIME OF THE YEAR. THE GFS SHOWS PRECIPITABLE
WATER NEAR 2 INCHES ACROSS THE SOUTH HALF WITH LOW LEVEL NORTHEAST
WINDS 20-25 KNOTS. MOS POPS ARE ABOUT 40 PERCENT IN THE FAR NORTH
TO 70 PERCENT IN THE SOUTH. DID NOT GO THAT HIGH THOUGH...STAYING
ABOUT 20 PERCENT UNDER THOSE VALUES FOR NOW.
LOW LEVEL ONSHORE FLOW WILL STILL BE QUITE STRONG TUE NIGHT SO
HAVE HAD TO BUMP UP POPS FROM THE PREVIOUS FORECAST...WITH 20
PERCENT VALUES IN THE NORTH TO 40 IN THE FAR SOUTHEAST.
WITH SUCH BREEZY LOW LEVEL WINDS...THERE IS A SLIGHT CHANCE FOR
SOME HEAVY RAINFALL MAINLY ALONG THE TREASURE COAST.
SOME MARINE MODIFICATION AND CLOUD COVER WILL PRODUCE LOWER HIGH
TEMPS...ESPECIALLY ACROSS THE NORTH HALF.
WED-THU...
STRONG HIGH PRESSURE ALONG THE EASTERN SEABOARD WILL MAINTAIN A
BREEZY EASTERLY WIND FLOW. FRONTAL BAND MOISTURE IS FORECAST TO
LINGER ACROSS THE AREA...PARTICULARLY THE SOUTH. HENCE HAVE HAD TO
BUMP UP PREVIOUS POPS TO 20 PERCENT NORTH AND 50 PERCENT SOUTHEAST
ON WED. RAIN CHANCES LOOK A LITTLE LESS THU AS RIDGING ALOFT IS
INDICATED AND HAVE 20 PERCENT FOR MOST OF THE AREA AND 30 PERCENT
ALONG THE TREASURE COAST.
FRI-MON...
DEEP LAYER RIDGING OVER THE WESTERN ATLANTIC IS FORECAST TO SHOVE
HIGHEST MOISTURE TO OUR SOUTH FRI-SAT AND HAVE CONTINUED OUR DRY
FORECAST FOR THE MOST PART. THERE COULD BE A FEW ATLANTIC SHOWERS
PUSHING ASHORE MAINLY IN THE FAR SOUTH FRI.
THE NEXT FRONT IS FORECAST TO DROP THROUGH SUNDAY OR SUNDAY NIGHT.
MOISTURE LOOKS LIMITED SO ONLY HAVE SLIGHT CHANCE POPS WITH IT. IT
IS STILL A LONG WAY OUT BUT THE GFS AND ECMWF SUGGEST THAT THERE
WILL BE A LITTLE MORE COOLING WITH THIS FRONT...BACK TO SLIGHTLY
BELOW NORMAL...WHICH WOULD BE A CHANGE FROM THE MOSTLY ABOVE
NORMAL TEMPS WE HAVE HAD THIS MONTH.
&&
.AVIATION...THRU 18/15Z...PREVAILING CIGS AOA FL120 N OF KMLB-KGIF
WITH AREAS CIGS BTWN FL040-060 ALONG AND N OF KISM-KTIX...PATCHY
MVFR/BRIEF LCL IFR VSBYS IN BR/FG. BTWN 18/15Z-18/17Z...SFC
WNDSHFT FM SW TO E BLO 10KTS BTWN KTIX-KSUA...PREVAILING CIGS AOA
FL120 ALL SITES WITH AREAS CIGS BTWN FL040-060 N OF KMLB-KGIF. AFT
18/17Z...VCSH ALL SITES WITH PREVAILING CIGS BTWN FL040-60.
&&
.MARINE...
TODAY-TONIGHT...WEAK HIGH PRES RIDGE BISECTING THE FL PENINSULA WILL
GENERATE A LIGHT TO GENTLE S/SW BREEZE THRU THE DAY. A WEAKENING
COLD FRONT WILL PUSH INTO CENTRAL FLORIDA OVERNIGHT...FORCING WINDS
N OF SEBASTIAN INLET TO VEER TO THE N/NW AND FRESHEN TO 15-20KTS
THROUGH THE PREDAWN HRS. SEAS 2-3FT NEARSHORE AND 3-4FT OFFSHORE
THRU MIDNIGHT...BUILDING TO 3-4FT NEARSHORE AND 4-5FT OFFSHORE BY
DAYBREAK.
TUE-FRI...STRONG HIGH PRESSURE ALONG THE EASTERN SEABOARD WILL
PRODUCE A TIGHT GRADIENT INTO LATE WEEK. ENOUGH CONFIDENCE EXISTS
TO INITIATE ADVISORIES ON TUE FOR THE WATERS FROM SEBASTIAN INLET
NORTHWARD. EXPECT THE ADVISORY TO COVER ALL OF THE WATERS BY TUE
NIGHT OR WED.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 82 65 75 64 / 50 60 20 20
MCO 86 65 77 64 / 50 60 30 20
MLB 83 67 80 70 / 40 50 40 30
VRB 84 67 82 72 / 40 40 50 40
LEE 84 64 76 61 / 50 60 20 20
SFB 84 65 76 63 / 50 60 30 20
ORL 85 65 77 64 / 50 60 30 20
FPR 84 67 81 72 / 30 40 50 40
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY FROM 10 AM TUESDAY TO 4 AM EST THURSDAY FOR
COASTAL WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY
LINE OUT 20 NM-WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD
COUNTY LINE 20 TO 60 NM OFFSHORE.
SMALL CRAFT ADVISORY FROM 4 PM TUESDAY TO 4 AM EST THURSDAY FOR
COASTAL WATERS FROM VOLUSIA BREVARD COUNTY LINE TO
SEBASTIAN INLET OUT 20 NM-WATERS FROM VOLUSIA BREVARD
COUNTY LINE TO SEBASTIAN INLET 20 TO 60 NM OFFSHORE.
&&
$$
SHORT TERM...BRAGAW
LONG TERM....LASCODY
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
413 AM EST MON NOV 18 2013
.SHORT TERM /TODAY THROUGH TONIGHT/...
AT THE SURFACE...COLD FRONT MOVING THROUGH WILL BRING SHOWERS ALONG
AND AHEAD OF IT THROUGH EARLY TO MIDDAY MONDAY ENDING FROM NORTH TO
SOUTH AS IT MOVES THROUGH. ALOFT...MAIN UPPER LEVEL ENERGY
RESPONSIBLE FOR THE SEVERE OUTBREAK ON SUNDAY ACROSS THE OHIO VALLEY
REGION IS MOVING THROUGH THE GREAT LAKES AND AWAY FROM OUR REGION.
END RESULT IS GENERALLY ZONAL FLOW IN THE MID AND UPPER LEVELS
ACROSS THE SOUTHEAST U.S. WITH SURFACE HIGH PRESSURE BUILDING IN
BEHIND THE FRONT. HAVE KEPT HIGH POPS IN WITH THE FRONT AS IT
PROGRESSES SOUTH AND EAST BUT TAPER THEM OFF QUICKLY BEHIND. HAVE
ALSO REMOVED ALL MENTION OF THUNDER AS INSTABILITY IS ALL BUT GONE.
MAIN CONCERN WITH THE FRONT IS GUSTY WINDS WITH THE SHOWERS MIXING
SOME OF THE STRONG WINDS OFF THE SURFACE DOWN. VAD WINDS SHOWING 20
TO 30 KTS IN THE LOWEST FEW THOUSAND FEET. HAVE ALREADY SEEN SOME
GUSTS TO NEAR 40 MPH ACROSS NORTH GA WITH SOME OF THE SHOWERS.
WINDS WILL PICK UP THROUGH THE DAY AS THE CLEARING LINE PROGRESSES
THROUGH THE REGION AND THE SURFACE RIDGE BUILDS IN.
OTHERWISE...THE REMAINDER OF THE SHORT TERM FORECAST LOOKS GOOD.
USED A MODEL BLEND FOR MOST ELEMENTS...WITH THE RUC AND HRRR IN THE
IMMEDIATE SHORT TERM.
30
.LONG TERM /TUESDAY THROUGH SUNDAY/...
QUIET WEATHER IS ON TAP FOR MOST OF THE LONG TERM PERIOD. A COLD
FRONT IS EXPECTED TO IMPACT THE CWFA LATE IN THE WEEK/EARLY PART OF
THE WEEKEND...BRINGING THE NEXT BEST CHANCES FOR PRECIPITATION.
HIGH PRESSURE WILL CONTINUE ACROSS THE SE US THROUGH WEDNESDAY
BEFORE BEGINNING TO SHIFT EASTWARD ON THURSDAY. A COLD FRONT WILL
MOVE INTO THE MISSISSIPPI RIVER VALLEY ON FRIDAY. THE FRONT IS
EXPECTED TO MOVE THROUGH THE CWFA ON SATURDAY...WITH HIGH PRESSURE
RETURNING FOR THE REMAINDER OF THE WEEKEND INTO THE EARLY PART OF
NEXT WEEK.
PRECIP CHANCES WILL BEGIN TO INCREASE LATER ON THURSDAY AS MOISTURE
BEGINS TO INCREASE AHEAD OF THE APPROACHING FRONTAL BOUNDARY. THE
FRONT IS STILL PROGGED TO COME THROUGH DURING THE DAY ON
SATURDAY...WITH THE MODELS INDICATING SOME MARGINAL INSTABILITY AT
THIS TIME. WILL KEEP THE MENTION OF THUNDER.
STRONG HIGH PRESSURE WILL BUILD BEHIND THE FRONTAL BOUNDARY...AND
BREEZY/WIND CONDITIONS ARE POSSIBLE SATURDAY NIGHT INTO SUNDAY. IN
ADDITION...A COLDER AND DRIER AIRMASS WILL SETTLE OVER THE SOUTHERN
STATES.
NLISTEMAA
&&
AVIATION...
06Z UPDATE...
COLD FRONT ENTERING NORTHWEST GA WITH A LINE OF SHOWERS NOTED ON
RADAR IN ASSOCIATION WITH THE FRONT. BASED ON CURRENT SPEED AM
PROJECTING AN ARRIVAL TIME AT ATL BTW 09Z AND 10Z. HAVE REFLECTED
THIS IN THE 06Z TAF ISSUANCE BY MOVING THINGS UP AN HOUR. EXPECT
IFR AND EVEN SOME LIFR CONDITIONS OFF AND ON UNTIL THE FRONT
PASSES AT ALL TAF SITES. PREVIOUS FORECAST LOOKS GOOD BEYOND
FRONTAL PASSAGE WITH STRONG NORTHWEST WINDS DURING THE DAY TODAY
AND RELAXING AFTER SUNSET AND OTHERWISE VFR CONDITIONS.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM CONFIDENCE ON LIFR CONDITIONS WITH FRONT...HIGH CONFIDENCE
ON ALL OTHER ELEMENTS.
30
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 72 46 59 36 / 20 0 5 0
ATLANTA 71 47 59 38 / 30 0 0 5
BLAIRSVILLE 66 38 56 32 / 20 0 0 0
CARTERSVILLE 69 42 58 36 / 30 0 0 0
COLUMBUS 77 53 64 41 / 70 0 5 5
GAINESVILLE 68 45 57 36 / 20 5 0 0
MACON 78 50 62 38 / 60 5 5 5
ROME 68 43 58 36 / 20 0 0 5
PEACHTREE CITY 73 45 60 37 / 30 0 5 5
VIDALIA 80 55 63 41 / 50 10 5 5
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...30
LONG TERM....NLISTEMAA
AVIATION...30
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1252 AM EST MON NOV 18 2013
.SYNOPSIS...
HIGH PRESSURE EAST OF NEW ENGLAND WILL SLIDE TO THE EAST. DEEPENING
LOW PRESSURE OVER THE WESTERN GREAT LAKES WILL MOVE NORTHEAST INTO
CANADA...PUSHING A COLD FRONT ACROSS THE LOCAL AREA EARLY MONDAY.
HIGH PRESSURE THEN RETURNS FOR THE MIDDLE OF THE WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
SURFACE ANALYSIS SHOWS A ~980MB LOW JUST NORTH OF LAKE SUPERIOR IN
SOUTHERN ONTARIO, WITH A STRONG COLD FRONT SOUTH THROUGH EASTERN
ILLINOIS TO NORTHEAST TEXAS. ALOFT, MID EVENING WATER VAPOR SAT
IMAGERY SHOWING NEGATIVELY TILTED SHORT WAVE TROUGH PUSHING E-NE
FROM THE MID MISSOURI VALLEY TOWARDS THE UPPER MIDWEST.
RADAR MOSAIC INDICATES A BATCH OF LIGHT RAIN ACROSS SOUTHWEST
VIRGINIA.
A WEAK AREA OF SUBTLE UPPER VORT/WEAK LIFT HAS ALLOWED SOME
SCATTERED SHOWERS/SPRINKLES TO CROP UP IN THE WARM SECTOR THIS
EVENING. HAVE REORGANIZED POPS SLIGHTLY AND WILL GO WITH ISO/SCT
SHRA WORDING EARLY THIS EVENING. HRRR HAS HANDLED RADAR TRENDS
REASONABLY WELL THIS EVENING...WITH ITS SOLUTION KEEPING AREAL
COVERAGE OF SHRAS RATHER SPOTTY THROUGH MUCH OF THE NIGHT. THIS
DOES MAKE SENSE GIVEN RATHER ANEMIC FORCING WITH PRE-FRONTAL PCPN.
SHOWERS DO INCREASE IN COVERAGE LATE W/AFOREMENTIONED COLD FRONT
DROPPING INTO THE NW CORNER OF THE CWA AROUND 09Z. A NARROW LINE
OF SHOWERS LOOKS TO ACCOMPANY THE FRONT...MOST LIKELY WITH BEST
FORCING/CONVERGENCE OVER THE NORTHERN HALF OF THE AREA. HAVE
LIKELY POPS OVER THIS AREA WITH THE FRONTAL PASSAGE...WITH HIGH
CHC POPS FARTHER SOUTH. FRONT SWEEPS QUICKLY TO THE EAST, WITH
DRYING ALOFT QUICKLY BRINGING AN END TO PCPN BEHIND THE FRONT. BY
12Z...THE FRONT WILL EXTEND FROM THE EASTERN PART OF THE NORTHERN
NECK THROUGH THE RICHMOND METRO AREA AND INTO NORTH CENTRAL NC.
PRE-FRONTAL S/SW WINDS WL INCREASE OVER THE NEXT FEW HRS, KEEPING
TEMPERATURES ON THE MILD SIDE. DESPITE STRONG SHEAR...KEPT TSTMS
OUT OF THE FCST. CAPE WILL BE VERY LIMITED AND THE SURFACE WILL
REMAIN STABLE. A FEW GUSTS TO AROUND 30 MPH WILL BE PSBL NEAR THE
FRONT AND ASSOCIATED SHOWERS.
TEMPERATURES HAVE LEVELED OFF THIS EVENING...AND EXPECT STEADY
TEMPS TO RISE SLIGHTLY OVERNIGHT AHEAD OF THE FRONT. EARLY
MORNING LOW TEMPERATURES TO RANGE FROM 60 TO 65...WITH UPR 50S
BEHIND THE FRONT OVER LOUISA AND FLUVANNA COUNTIES.
ON MONDAY...THE FRONT MOVES OFF THE COAST AROUND MIDDAY. PCPN ENDS
IN MOST AREAS IN THE MRNG BUT KEPT SLGT CHC POPS ON THE NC COAST
THROUGH 20Z. DOWNSLOPE FLOW SHOULD BRING SUNSHINE BEHIND THE FRONT
ACROSS THE WESTERN CWA...AND ALLOW TEMPERATURES TO BE MILD ON
MONDAY. EXPECT MAXIMA IN THE LOW TO MID 70S ACROSS MOST OF THE AREA
EXCEPT NEAR 70 WEST OF INTERSTATE 95. TEMPERATURES WILL BEGIN TO
FALL DURING THE AFTN OVER WESTERN SECTIONS. WINDS WILL BE BREEZY
FROM THE WEST AND NORTHWEST...ESPECIALLY NEAR THE COAST.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
MONDAY NIGHT THROUGH TUESDAY NIGHT IS STRAIGHTFORWARD WITH DRY
CONDITIONS AND A MOSTLY CLEAR SKY. HIGH PRESSURE WILL BE OVER THE
NORTHEASTERN STATES WITH RIDGING INTO THE MID ATLANTIC. THE CORE OF
THE RIDGE WILL BE OVERHEAD TUESDAY WHICH WILL REDUCE MIXING SOME.
MODELS ARE ALL OVER THE PLACE WITH HIGH TEMPERATURES BUT STAYED
CLOSE TO OUR PREVIOUS FORECAST AND MOS GUIDE. HIGH TEMPERATURES WILL
RANGE FROM 50 TO 55. ON WEDNESDAY...NE TO E FLOW WILL RESULT IN AN
INCREASE IN CLOUDS AND TEMPERATURES A BIT LOWER...ESPECIALLY OVER
THE PIEDMONT. READINGS ARE EXPECTED TO RANGE FROM AROUND 50 IN THE
PIEDMONT TO THE MID 50S IN NE NORTH CAROLINA. KEPT SLGT CHC FOR
SHOWERS FOR THE NC COAST WITH SOME MODEL SUPPORT...ESPECIALLY FROM
THE GFS FOR THIS POSSIBILITY. LOW TEMPERATURES TUESDAY AND
WEDNESDAY MORNINGS WILL GENERALLY RANGE FROM 30 TO 35.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE SHIFTS OFF THE NRN NEW ENGLAND COAST WED NIGHT AND
THU...THEN STARTS TO SLIDE DOWN THE ATLANTIC COAST THU NIGHT AND
FRI. THE PRESSURE GRADIENT WILL REMAIN TIGHT OVER SERN PORTIONS OF
THE REGION WED NIGHT...FOLLOWED BY ADDITIONAL RELAXING OF THE
GRADIENT IN THIS AREA BY THU AFTN. NW-N WINDS WILL REMAIN BREEZY
NEAR COASTAL AREAS WED THROUGH FRI DUE TO THE PERSISTENT ONSHORE
FLOW. AS WINDS BECOME MORE NE-E ON WED...EXPECT LOW CLOUDS TO MOVE
INTO COASTAL AREAS FROM THE OCEAN. THIS COULD RESULT IN LIGHT RAIN
SHOWERS AND OCCASIONAL DRIZZLE WED/THU. AN APPROACHING COLD FRONT
WILL BOOST TEMPS ACROSS THE REGION FRI/FRI NIGHT...FOLLOWED BY
ANOTHER POTENTIAL BLAST OF ARCTIC AIR SAT/SUN.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
FIRST BATCH OF PRE FRONTAL SHOWERS WILL QUICKLY MOVE OFFSHORE
NEXT FEW HOURS. DESPITE A GUSTY SOUTH WIND UP TO 20 KTS...IFR
STRATUS HAS DEVELOPED ACROSS THE PIEDMONT AND WILL LIKELY MOVE
EAST. THUS...EXPECT CHANGEABLE CIGS AND VSBYS NEXT FEW HOURS WITH
SPORATIC SHOWERS.
MAIN COLD FRONT PROGGED BETWEEN 8-12Z. LATEST MODEL DATA SUGGESTS
LINE OF CONVECTION WITH THIS FRONT WEAKENS AS IT CROSSES THE
MOUNTAINS DUE TO LACK OF UPR LEVEL SUPPORT. STILL CAN`T RUKE OUT A
GUSTY SHOWER WITH THE ACTUAL FROPA AT RIC/SBY WHERE BEST SUPPORT
WILL BE. SCT SHOWERS CONTINUE ACROSS SERN TAF SITES WITH GUSTY
S-SW WINDS UP TO 25 KT.
RAPID IMPROVEMENT AFTER FROPA. DECREASING CLOUDINESS THRU 18Z.
WINDS SHIFT INTO W-NW AT 10-20 KTS. SKC EXPECTED AFTER 00Z.
&&
.MARINE...
WEAK HIGH PRESSURE CONTINUES TO BREAKDOWN THIS EVENING AS E-SE WINDS
REMAIN AOB 10 KT WITH SEAS AVERAGING 1-3 FT. THIS ALL CHANGES
OVERNIGHT AS A VERY STRONG COLD FRONT APPROACHES THE
REGION...CAUSING THE SFC PRESSURE GRADIENT TO TIGHTEN AND THE WINDS
TO VEER TO THE S. WINDS SHIFT TO THE SW AND QUICKLY INCREASE INTO
LOW-END SCA THRESHOLDS JUST AHEAD OF AND ALONG THE FRONTAL PASSAGE
DURING THE PRE-DAWN AND EARLY DAYLIGHT HOURS MON MORNING. SPEEDS
OF 20-25 KT BAY/COASTAL WATERS AND 15-20 KT CURRITUCK SOUND SHOULD
BE ANTICIPATED DURING THE AFOREMENTIONED TIMEFRAME. WAVES ON CHES
BAY WILL QUICKLY BUILD TO 3-4 FT WHILE SEAS QUICKLY RESPOND AND JUMP
TO 4-6 FT FOR ALL COASTAL WATERS (UP TO 7 FT NEAR 20 NM FROM FENWICK
ISLAND TO CHINCOTEAGUE). SW WINDS TURN TO THE W-NW BEHIND THE
FRONTAL PASSAGE ON MON AND SPEEDS WILL DIMINISH BELOW SCA THRESHOLDS
DURING THE DAYTIME. THIS WILL BE SHORT-LIVED AS COLDER TEMPERATURES
FROM A MODIFIED ARCTIC AIRMASS MOVE OVER THE WATERS EARLY MON
EVENING THROUGH TUE. THIS PARTICULAR SET-UP WILL RESULT IN A NW-N
SURGE BEGINNING MON NIGHT AND CONTINUING THROUGH TUE NIGHT BEFORE
WINDS BEGIN TO DIMINISH ON WED. EXPECT THE STRONGEST SURGE TO OCCUR
EARLY TUE MORNING WHEN THE WIND DIRECTION TURNS FROM NW TO N. WIND
SPEEDS ARE ANTICIPATED TO INCREASE TO 20-25 KT (SOLID SCA
CONDITIONS) OVER ALL WATERS...WITH GUSTS TO AROUND 30 KT. RESPONDING
WAVES ARE EXPECTED TO REBUILD TO 4-5 FT OVER CHES BAY. SEAS ARE ALSO
EXPECTED TO BUILD FROM 3-4 FT MONDAY EVENING TO 5-6 FT EARLY TUE
MORNING. PREVIOUS FLAGS FOR COASTAL WATERS NORTH OF THE VA/NC BORDER
AND CHES BAY HAVE BEEN EXTENDED THROUGH TUESDAY EVENING...DESPITE
THE LULL IN WINDS MON AFTN. ADDITIONAL FLAGS HAVE BEEN ISSUED FOR
SRN COASTAL WATERS FROM THE VA/NC BORDER TO CURRITUCK
LIGHT...CURRITUCK SOUND FOR TONIGHT THROUGH TUE EVENING. AN
ADDITIONAL SCA FLAG HAS BEEN ISSUED FOR THE LOWER JAMES RIVER FOR
LATE TONIGHT INTO MON MORNING. HEADLINES FOR REST OF ERN VA RIVERS
WILL LIKELY BE NEEDED FOR MON NIGHT INTO TUESDAY BUT WILL HOLD OFF
ON ISSUING THEM ATTM.
HIGH PRESSURE BEGINS TO SHIFT ACROSS THE OH VALLEY ON TUE...THEN
SHIFTS OVER NRN NEW ENGLAND TUE NIGHT THROUGH WED. THE PRESSURE
GRADIENT WILL REMAIN TIGHT OVER THE WATERS DURING THIS TIMEFRAME.
N WINDS WILL REMAIN ELEVATED IN LOW-END SCA WIND SPEEDS EARLY TUE
NIGHT...THEN START TO DIMINISH AFTER MIDNIGHT INTO WED. EXPECT
WINDS AFTER MIDNIGHT TO AOB 15 KT BAY/RIVERS/SOUND...AOB 20 KT
COASTAL WATERS. AS THE NRN NEW ENGLAND HIGH PRESSURE CENTER MOVES
ACROSS NRN NEW ENGLAND TO JUST OFF ITS COAST ON WED NIGHT INTO
THU...WINDS BECOME MORE NE-E/ONSHORE. SPEEDS WILL BEGIN TO SLACKEN
THROUGH WED AND DIMINISH FURTHER WED NIGHT INTO THU. WAVES ON CHES
BAY SHOULD START TO SUBSIDE BY WED AFTN...EXCEPT THE MOUTH OF THE
BAY WHERE ONSHORE WINDS WILL KEEP WAVES HIGHER THROUGH WED NIGHT.
SEAS SHOULD ALSO BE SLOW TO SUBSIDE BELOW 5 FT UNTIL SOMETIME THU
NIGHT/FRI. HIGH PRESSURE LINGERS OFF THE NRN NEW ENGLAND COAST
THROUGH FRI AND ONSHORE FLOW WILL PERSIST.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST TUESDAY FOR ANZ630>634-650-
652-654-656-658.
SMALL CRAFT ADVISORY UNTIL NOON EST TODAY FOR ANZ638.
&&
$$
SYNOPSIS...LSA
NEAR TERM...MAM/LSA
SHORT TERM...LSA
LONG TERM...BMD
AVIATION...MPR
MARINE...BMD
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1245 AM EST MON NOV 18 2013
.SYNOPSIS...
A STRONG COLD FRONT WILL PASS THROUGH THE REGION LATE TONIGHT INTO
EARLY MONDAY MORNING. HIGH PRESSURE BEHIND THE COLD FRONT WILL
BUILD OVERHEAD LATE MONDAY THROUGH WEDNESDAY. THE HIGH WILL MOVE
OFF THE COAST THURSDAY AND A COLD FRONT MAY IMPACT THE AREA FRIDAY
AND SATURDAY.
&&
.NEAR TERM /THROUGH TODAY/...
UPDATE...SEVERE THUNDERSTORM WATCH 572 IS IN EFFECT FOR COUNTIES
ALONG AND WEST OF THE BLUE RIDGE AND PARTS OF THE PIEDMONT REGION.
00Z RADAR AND OBSERVATIONS INDICATE THE COLD FRONT HAS REACHED
WESTERN OHIO...AND CONTINUES TO PUSH RAPIDLY EASTWARD. SOME
AREAS OF LIGHT RAIN/SHOWERS HAVE MOVED INTO THE MOUNTAINS AND
PIEDMONT. THESE WILL IMPACT THE FORECAST AREA OVER THE NEXT
COUPLE OF HOURS. AFTER THE FIRST BATCH OF RAIN...A RESPITE IS
LIKELY FOR A WHILE THIS EVENING AS A DRY SLOT NOTED ON WATER VAPOR
IMAGERY MOVES INTO THE AREA.
BASED ON SHORT-TERM MODEL OUTPUT...THE COLD FRONT AND ITS
ASSOCIATED LINE OF SHOWERS IS EXPECTED TO REACH THE POTOMAC
HIGHLANDS AROUND 11PM - MIDNIGHT...THEN STEADILY CROSS THE CWA
OVERNIGHT...REACHING CHESAPEAKE BAY AROUND 5AM. THERE HAS BEEN
SOME RUN-TO-RUN INCONSISTENCY IN TERMS OF HOW WELL SHOWER ACTIVITY
WILL REMAIN ORGANIZED AS IT CROSSES THE CWA...ESPECIALLY EAST OF
THE BLUE RIDGE. HRRR HAD PREVIOUSLY HELD THE LINE OF HEAVY
SHOWERS TOGETHER...BUT ITS 22Z RUN JUST IN DETERIORATES THE LINE
SOUTH OF THE POTOMAC RIVER AS IT MOVES EWD. WHEREVER THE LINE
HOLDS TOGETHER...IT WILL HAVE THE POTENTIAL TO TAP INTO A VERY
STRONG LOW LEVEL JET STREAM...WHICH SHOULD REACH AROUND 55-65KTS
AT 850MB AS IT CROSSES THE AREA. WITH IT...GUSTY WINDS ARE
EXPECTED...WITH AN ISOLATED DAMAGING WIND THREAT. ISOLATED THUNDER
REMAINS POSSIBLE AS WELL.
A WIND ADVISORY IS IN EFFECT ACROSS MUCH OF THE POTOMAC HIGHLANDS
AND CENTRAL AND SOUTHERN SHENANDOAH VALLEYS FROM 9PM UNTIL 6 AM
MONDAY. THIS ADVISORY IS PRIMARILY FOR ELEVATIONS ABOVE 2500 FEET
ALONG THE ALLEGHENY FRONT AND BLUE RIDGE. WINDS LOOK LIKE THEY
WILL INCREASE QUICKLY THIS EVENING AND GUST BETWEEN 45 AND 55 MPH
AT THE RIDGE TOPS LATER THIS EVENING AND OVERNIGHT.
WENT WITH NAM MODEL FOR LOW TEMPERATURES TONIGHT...THE WARMER MODEL.
WE HAVE WARM AIR ADVECTION ON A PERSISTENT SOUTHERLY WIND PLUS
CLOUD COVER AHEAD OF THE COLD FRONT.
THE COLD FRONT WILL MOVE OFF TO OUR EAST MONDAY MORNING AND LOW
PRESSURE WILL TRACK ACROSS EASTERN CANADA MONDAY WHILE HIGH
PRESSURE BUILDS OVER THE CENTRAL CONUS. A WESTERLY FLOW BEHIND THE
FRONT WILL DRY THINGS OUT QUICKLY FOR MONDAY...ALLOWING FOR PLENTY
OF SUNSHINE. MONDAY WILL BE MILD DUE TO SUNSHINE ALONG WITH A
DOWNSLOPING FLOW...DESPITE COLD ADVECTION BEHIND THE FRONT. MAX
TEMPS WILL RANGE FROM THE UPPER 50S AND LOWER 60S IN THE
SHENANDOAH VALLEY TO THE UPPER 60S AND LOWER 70S NEAR WASHINGTON
AND BALTIMORE AS WELL AS SOUTHERN MARYLAND. CHILLIER CONDITIONS
ARE EXPECTED IN THE MOUNTAINS WITH TEMPS IN THE 40S. BREEZY
CONDITIONS ARE EXPECTED MONDAY DUE TO A DEEP MIXING LAYER.
WESTERLY WINDS WILL GUST FREQUENTLY AROUND 25 TO 30 MPH WITH GUSTS
AROUND 40 MPH IN THE MOUNTAINS.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
HIGH PRESSURE WILL BUILD OVERHEAD MONDAY NIGHT THROUGH WEDNESDAY.
DRY AND SEASONABLY CHILLY CONDITIONS ARE EXPECTED DURING THIS
TIME.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE WILL SLOWLY DRIFT OFF THE MID-ATLANTIC COAST WEDNESDAY
NIGHT INTO THURSDAY AS UPPER-LEVEL TROUGHING APPROACHES FROM THE
WEST. SURFACE REFLECTION IN THE FORM OF A COLD FRONT WILL APPROACH
THE AREA LATE THURSDAY INTO FRIDAY. SEASONABLE TEMPERATURES ARE
EXPECTED AHEAD OF THE FRONT THROUGH LATE IN THE WEEK. 17/12Z GFS
OPERATIONAL IN BETTER AGREEMENT WITH ITS 06Z ENSEMBLE MEAN AND
17/00Z ECMWF OPERATIONAL/ENSEMBLE MEAN WITH OVERALL PATTERN AND
TIMING OF THE FRONT...ALTHOUGH THE ECMWF TRIES TO DEVELOP A WAVE ON
THE FRONT AS IT CROSSES THE AREA. THE ECMWF IS ALSO A BIT COLDER
FRIDAY NIGHT. FOR NOW...FOLLOWED WPC GUIDANCE WHICH IS A 70/30 BLEND
OF THE 00Z ECMWF ENSEMBLE MEAN/06Z GFS ENSEMBLE MEAN.
THIS RESULTS IN A CHANCE OF PRECIPITATION BEGINNING AND ENDING FROM
WEST TO EAST EARLY FRIDAY MORNING THROUGH SATURDAY. ALTHOUGH BOTH
THE GFS AND TO A GREATER EXTENT THE ECMWF HINT AT COLDER AIR MOVING
IN BEFORE PRECIPITATION ENDS...KEPT ANY MENTION OF SNOW SHOWERS
MIXED WITH RAIN WELL NORTH AND WEST OF THE I-95 CORRIDOR GIVEN
CLIMATOLOGY AND INHERENT UNCERTAINTY/MODEL SPREAD AT THIS TIME RANGE.
A BLAST OF ARCTIC AIR FOLLOWS THE COLD FRONT LEADING TO BELOW NORMAL
TEMPERATURES AREA-WIDE NEXT WEEKEND.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
COLD FRONT WILL MOVE ACROSS THE TERMINALS IN THE NEXT FEW HOURS. A
THIN LINE OF SHOWERS WITH HEAVY RAINFALL AND GUSTY WINDS WILL
ACCOMPANY THE FRONT. AHEAD OF THE FRONT...GENERALLY MVFR
CIGS...WITH IFR LIKELY AS THE HEAVIER RAIN MOVES THROUGH.
AFTER THE FRONT MOVES THROUGH...VFR CONDITIONS WILL RETURN BY
SUNRISE...WITH WINDS SHIFTING TO THE WEST. GUSTS TO AROUND 20KT
WILL DEVELOP DURING THE MORNING AND SHOULD PERSIST THROUGH THE
AFTERNOON.
VFR CONDITIONS ARE EXPECTED MONDAY NIGHT THROUGH WEDNESDAY.
NORTHWEST WINDS WILL GUST AROUND 15 TO 20 KNOTS TUESDAY. WINDS
TUESDAY NIGHT AND WEDNESDAY WILL BE LIGHT. HIGH PRESSURE WILL
REMAIN OVER THE TERMINALS LATE IN THE WEEK.
&&
.MARINE...
A SMALL CRAFT ADVISORY IS IN EFFECT TONIGHT FOR SOUTHERLY WINDS
AHEAD OF A COLD FRONT. THERE IS POTENTIAL FOR SPECIAL MARINE
WARNINGS OVERNIGHT AS SHOWERS WITH GUSTY WINDS MOVE THROUGH THE WATERS.
GUSTY WESTERLY WINDS ARE EXPECTED BEHIND A COLD FRONT MONDAY. A
SMALL CRAFT ADVISORY IS IN EFFECT FOR THE WATERS. THE SMALL CRAFT
ADVISORY CONTINUES MONDAY NIGHT FOR THE MARYLAND CHESAPEAKE BAY AND
TIDAL POTOMAC RIVER FROM INDIAN HEAD TO SMITH POINT.
A SMALL CRAFT ADVISORY MAY BE NEEDED FOR PORTIONS OF THE WATERS
TUESDAY AND TUESDAY NIGHT. HIGH PRESSURE WILL BUILD OVERHEAD
WEDNESDAY. A RELATIVELY BENIGN SURFACE PRESSURE GRADIENT WILL
LIKELY LEAD TO SUB-SCA CONDITIONS ON AREA WATERS WEDNESDAY NIGHT
THROUGH FRIDAY. A COLD FRONT MAY BRING SHOWERS TO THE WATERS
FRIDAY INTO SATURDAY...FOLLOWED BY INCREASINGLY GUSTY NW FLOW.
&&
.TIDES/COASTAL FLOODING...
ANOMALIES WILL CONTINUE TO INCREASE TONIGHT AS THE SOUTHERLY FLOW
INCREASES. HOWEVER...A COLD FRONT IS EXPECTED TO MOVE THROUGH
OVERNIGHT...WITH WINDS SHIFTING TO THE WEST BEFORE MORNING HIGH
TIDE MONDAY. THEREFORE...MINOR COASTAL FLOODING IS NOT EXPECTED
AS OF NOW. WILL CONTINUE TO MONITOR ANOMALIES BECAUSE CERTAINTY IS
LOW DUE TO THE GUSTY SOUTHERLY FLOW.
WEST WINDS WILL CONTINUE BEHIND THE COLD FRONT MONDAY AND
ANOMALIES WILL DECREASE. TIDAL BLOWOUT IS POSSIBLE LATE MONDAY AND
TUESDAY.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...WIND ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR MDZ501.
VA...WIND ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR VAZ025>027-
029-030-036>040-503-504.
WV...WIND ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR WVZ055-
501>503-505-506.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST TUESDAY FOR ANZ530>534-536-
537-539>541-543.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ535-
538-542.
&&
$$
SYNOPSIS...BJL
NEAR TERM...KS/KLW
SHORT TERM...BJL
LONG TERM...DFH
AVIATION...KCS/DFH
MARINE...BJL/KLW/DFH
TIDES/COASTAL FLOODING...KCS
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1142 PM EST SUN NOV 17 2013
.SYNOPSIS...
A STRONG COLD FRONT WILL PASS THROUGH THE REGION LATE TONIGHT INTO
EARLY MONDAY MORNING. HIGH PRESSURE BEHIND THE COLD FRONT WILL
BUILD OVERHEAD LATE MONDAY THROUGH WEDNESDAY. THE HIGH WILL MOVE
OFF THE COAST THURSDAY AND A COLD FRONT MAY IMPACT THE AREA FRIDAY
AND SATURDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
UPDATE...SEVERE THUNDERSTORM WATCH 572 IS IN EFFECT FOR COUNTIES
ALONG AND WEST OF THE BLUE RIDGE AND PARTS OF THE PIEDMONT REGION.
00Z RADAR AND OBSERVATIONS INDICATE THE COLD FRONT HAS REACHED
WESTERN OHIO...AND CONTINUES TO PUSH RAPIDLY EASTWARD. SOME
AREAS OF LIGHT RAIN/SHOWERS HAVE MOVED INTO THE MOUNTAINS AND
PIEDMONT. THESE WILL IMPACT THE FORECAST AREA OVER THE NEXT
COUPLE OF HOURS. AFTER THE FIRST BATCH OF RAIN...A RESPITE IS
LIKELY FOR A WHILE THIS EVENING AS A DRY SLOT NOTED ON WATER VAPOR
IMAGERY MOVES INTO THE AREA.
BASED ON SHORT-TERM MODEL OUTPUT...THE COLD FRONT AND ITS
ASSOCIATED LINE OF SHOWERS IS EXPECTED TO REACH THE POTOMAC
HIGHLANDS AROUND 11PM - MIDNIGHT...THEN STEADILY CROSS THE CWA
OVERNIGHT...REACHING CHESAPEAKE BAY AROUND 5AM. THERE HAS BEEN
SOME RUN-TO-RUN INCONSISTENCY IN TERMS OF HOW WELL SHOWER ACTIVITY
WILL REMAIN ORGANIZED AS IT CROSSES THE CWA...ESPECIALLY EAST OF
THE BLUE RIDGE. HRRR HAD PREVIOUSLY HELD THE LINE OF HEAVY
SHOWERS TOGETHER...BUT ITS 22Z RUN JUST IN DETERIORATES THE LINE
SOUTH OF THE POTOMAC RIVER AS IT MOVES EWD. WHEREVER THE LINE
HOLDS TOGETHER...IT WILL HAVE THE POTENTIAL TO TAP INTO A VERY
STRONG LOW LEVEL JET STREAM...WHICH SHOULD REACH AROUND 55-65KTS
AT 850MB AS IT CROSSES THE AREA. WITH IT...GUSTY WINDS ARE
EXPECTED...WITH AN ISOLATED DAMAGING WIND THREAT. ISOLATED THUNDER
REMAINS POSSIBLE AS WELL.
A WIND ADVISORY IS IN EFFECT ACROSS MUCH OF THE POTOMAC HIGHLANDS
AND CENTRAL AND SOUTHERN SHENANDOAH VALLEYS FROM 9PM UNTIL 6 AM
MONDAY. THIS ADVISORY IS PRIMARILY FOR ELEVATIONS ABOVE 2500 FEET
ALONG THE ALLEGHENY FRONT AND BLUE RIDGE. WINDS LOOK LIKE THEY
WILL INCREASE QUICKLY THIS EVENING AND GUST BETWEEN 45 AND 55 MPH
AT THE RIDGE TOPS LATER THIS EVENING AND OVERNIGHT.
WENT WITH NAM MODEL FOR LOW TEMPERATURES TONIGHT...THE WARMER MODEL.
WE HAVE WARM AIR ADVECTION ON A PERSISTENT SOUTHERLY WIND PLUS
CLOUD COVER AHEAD OF THE COLD FRONT.
THE COLD FRONT WILL MOVE OFF TO OUR EAST MONDAY MORNING AND LOW
PRESSURE WILL TRACK ACROSS EASTERN CANADA MONDAY WHILE HIGH
PRESSURE BUILDS OVER THE CENTRAL CONUS. A WESTERLY FLOW BEHIND THE
FRONT WILL DRY THINGS OUT QUICKLY FOR MONDAY...ALLOWING FOR PLENTY
OF SUNSHINE. MONDAY WILL BE MILD DUE TO SUNSHINE ALONG WITH A
DOWNSLOPING FLOW...DESPITE COLD ADVECTION BEHIND THE FRONT. MAX
TEMPS WILL RANGE FROM THE UPPER 50S AND LOWER 60S IN THE
SHENANDOAH VALLEY TO THE UPPER 60S AND LOWER 70S NEAR WASHINGTON
AND BALTIMORE AS WELL AS SOUTHERN MARYLAND. CHILLIER CONDITIONS
ARE EXPECTED IN THE MOUNTAINS WITH TEMPS IN THE 40S. BREEZY
CONDITIONS ARE EXPECTED MONDAY DUE TO A DEEP MIXING LAYER.
WESTERLY WINDS WILL GUST FREQUENTLY AROUND 25 TO 30 MPH WITH GUSTS
AROUND 40 MPH IN THE MOUNTAINS.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
HIGH PRESSURE WILL BUILD OVERHEAD MONDAY NIGHT THROUGH WEDNESDAY.
DRY AND SEASONABLY CHILLY CONDITIONS ARE EXPECTED DURING THIS
TIME.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE WILL SLOWLY DRIFT OFF THE MID-ATLANTIC COAST WEDNESDAY
NIGHT INTO THURSDAY AS UPPER-LEVEL TROUGHING APPROACHES FROM THE
WEST. SURFACE REFLECTION IN THE FORM OF A COLD FRONT WILL APPROACH
THE AREA LATE THURSDAY INTO FRIDAY. SEASONABLE TEMPERATURES ARE
EXPECTED AHEAD OF THE FRONT THROUGH LATE IN THE WEEK. 17/12Z GFS
OPERATIONAL IN BETTER AGREEMENT WITH ITS 06Z ENSEMBLE MEAN AND
17/00Z ECMWF OPERATIONAL/ENSEMBLE MEAN WITH OVERALL PATTERN AND
TIMING OF THE FRONT...ALTHOUGH THE ECMWF TRIES TO DEVELOP A WAVE ON
THE FRONT AS IT CROSSES THE AREA. THE ECMWF IS ALSO A BIT COLDER
FRIDAY NIGHT. FOR NOW...FOLLOWED WPC GUIDANCE WHICH IS A 70/30 BLEND
OF THE 00Z ECMWF ENSEMBLE MEAN/06Z GFS ENSEMBLE MEAN.
THIS RESULTS IN A CHANCE OF PRECIPITATION BEGINNING AND ENDING FROM
WEST TO EAST EARLY FRIDAY MORNING THROUGH SATURDAY. ALTHOUGH BOTH
THE GFS AND TO A GREATER EXTENT THE ECMWF HINT AT COLDER AIR MOVING
IN BEFORE PRECIPITATION ENDS...KEPT ANY MENTION OF SNOW SHOWERS
MIXED WITH RAIN WELL NORTH AND WEST OF THE I-95 CORRIDOR GIVEN
CLIMATOLOGY AND INHERENT UNCERTAINTY/MODEL SPREAD AT THIS TIME RANGE.
A BLAST OF ARCTIC AIR FOLLOWS THE COLD FRONT LEADING TO BELOW NORMAL
TEMPERATURES AREA-WIDE NEXT WEEKEND.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
A COLD FRONT WILL MOVE THROUGH THE REGION OVERNIGHT INTO THE EARLY
MORNING HOURS MONDAY. A FEW PERIODS OF SHOWERS ARE EXPECTED...AND
MOST TERMINALS WILL SEE BRIEF HEAVY RAINFALL WITH POTENTIAL FOR
ISOLATED THUNDERSTORMS. AMENDMENTS LIKELY FOR TEMPO GROUPS FOR
THIS HEAVY RAINFALL ACTIVITY AND ASSOCIATED REDUCED CIGS/VSBYS AS
THE ACTIVITY APPROACHES AND TIMING BECOMES MORE CERTAIN. WINDS
WILL INCREASE AS THE EVENING PROGRESSES...WITH GUSTS AROUND 25KTS
AT DC METRO TERMINALS. HIGHER GUSTS POSSIBLE WITH ANY HEAVY
SHOWER/TSTM ACTIVITY. WINDS WILL SHIFT TO THE WEST AFTER THE FRONT
MOVES THROUGH LATE TONIGHT OR EARLY MONDAY.
VFR CONDITIONS ARE EXPECTED MONDAY THROUGH WEDNESDAY. WESTERLY WINDS
WILL GUST AROUND 25 KNOTS MONDAY BEFORE DIMINISHING TOWARD SUNSET.
NORTHWEST WINDS WILL GUST AROUND 15 TO 20 KNOTS TUESDAY. WINDS
TUESDAY NIGHT AND WEDNESDAY WILL BE LIGHT. HIGH PRESSURE WILL
REMAIN OVER THE TERMINALS LATE IN THE WEEK.
&&
.MARINE...
A SMALL CRAFT ADVISORY IS IN EFFECT TONIGHT FOR SOUTHERLY WINDS
AHEAD OF A COLD FRONT. THERE IS POTENTIAL FOR SPECIAL MARINE
WARNINGS OVERNIGHT AS SHOWERS WITH GUSTY WINDS MOVE THROUGH THE WATERS.
GUSTY WESTERLY WINDS ARE EXPECTED BEHIND A COLD FRONT MONDAY. A
SMALL CRAFT ADVISORY IS IN EFFECT FOR THE WATERS. THE SMALL CRAFT
ADVISORY CONTINUES MONDAY NIGHT FOR THE MARYLAND CHESAPEAKE BAY AND
TIDAL POTOMAC RIVER FROM INDIAN HEAD TO SMITH POINT.
A SMALL CRAFT ADVISORY MAY BE NEEDED FOR PORTIONS OF THE WATERS
TUESDAY AND TUESDAY NIGHT. HIGH PRESSURE WILL BUILD OVERHEAD
WEDNESDAY. A RELATIVELY BENIGN SURFACE PRESSURE GRADIENT WILL
LIKELY LEAD TO SUB-SCA CONDITIONS ON AREA WATERS WEDNESDAY NIGHT
THROUGH FRIDAY. A COLD FRONT MAY BRING SHOWERS TO THE WATERS
FRIDAY INTO SATURDAY...FOLLOWED BY INCREASINGLY GUSTY NW FLOW.
&&
.TIDES/COASTAL FLOODING...
ANOMALIES WILL CONTINUE TO INCREASE TONIGHT AS THE SOUTHERLY FLOW
INCREASES. HOWEVER...A COLD FRONT IS EXPECTED TO MOVE THROUGH
OVERNIGHT...WITH WINDS SHIFTING TO THE WEST BEFORE MORNING HIGH
TIDE MONDAY. THEREFORE...MINOR COASTAL FLOODING IS NOT EXPECTED
AS OF NOW. WILL CONTINUE TO MONITOR ANOMALIES BECAUSE CERTAINTY IS
LOW DUE TO THE GUSTY SOUTHERLY FLOW.
WEST WINDS WILL CONTINUE BEHIND THE COLD FRONT MONDAY AND
ANOMALIES WILL DECREASE. TIDAL BLOWOUT IS POSSIBLE LATE MONDAY AND
TUESDAY.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...WIND ADVISORY UNTIL 6 AM EST MONDAY FOR MDZ501.
VA...WIND ADVISORY UNTIL 6 AM EST MONDAY FOR VAZ025>027-029-030-
036>040-503-504.
WV...WIND ADVISORY UNTIL 6 AM EST MONDAY FOR WVZ055-501>503-505-506.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST TUESDAY FOR ANZ530>534-536-
537-539>541-543.
SMALL CRAFT ADVISORY UNTIL 6 PM EST MONDAY FOR ANZ535-538-542.
&&
$$
SYNOPSIS...BJL
NEAR TERM...KS/KLW
SHORT TERM...BJL
LONG TERM...DFH
AVIATION...BJL/KS/DFH
MARINE...BJL/KLW/DFH
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1257 AM EST MON NOV 18 2013
.SYNOPSIS...
A LARGE STORM SYSTEM WILL STRENGTHEN OVER THE GREAT LAKES AND
BLAST A COLD FRONT THROUGH OUR REGION BETWEEN MIDNIGHT AND DAWN
TONIGHT. THE FRONT WILL BE ACCOMPANIED BY A GUSTY LINE OF SHOWERS
AND ISOLATED THUNDERSTORMS. LOCALIZED DAMAGING WINDS WILL BE POSSIBLE.
COLDER AIR WILL MOVE IN BEHIND THE FRONT...WITH GUSTY WINDS
CONTINUING MONDAY. SOME LAKE EFFECT SNOW SHOWERS CAN BE EXPECTED
MONDAY NIGHT INTO TUESDAY MORNING IN CENTRAL NEW YORK.
&&
.NEAR TERM /THROUGH TODAY/...
815 PM UPDATE...
982MB LOW IS CURRENTLY IN VICINITY OF EXTREME EASTERN UP OF
MICHIGAN. CDFNT EXTNDS TWD THE SOUTH ACROSS CNTRL LWR MICHIGAN AND
THRU WRN OHIO WITH WINDS GUSTING ANYWHERE BTWN 35-50KTS.
CONVECTIVE LINE HAS MADE IT INTO NE OH, HWVR CLD-GROUND LIGHTNING
IS ALMOST NON-EXISTENT WITH THE LINE WITH THE MAIN LIGHTNING
STRIKES OVR ONTARIO AND SRN KY. IN-CLOUD LIGHTNING IS NOT MUCH
BETTER AS JUST A FEW STRIKES EXIST OVR ERN OHIO. 00Z KBUF RAOB
SHOWING MINIMAL CAPES AND POOR LAPSE RATES AT THIS TIME AND ONLY
EXPECT THAT TO CONTINUE AS THE LINE HEADS EAST PER KALY SNDG.
LATEST HRRR CONTINUES TO SUGGEST A VRY THIN CONVECTIVE LINE MVG
THRU BTWN 05Z-09Z, PLACING THE LINE ALONG THE I-81 CORRIDOR BY
07Z. ALL INDICATIONS ARE THAT THIS TIMING LOOKS TO BE RIGHT ON
TARGET. THUNDER THREAT LOOKS ISOLD AT BEST BUT STILL EXPECT A VRY
BRIEF WINDOW OF STRONG WINDS ALONG THE FRONT. THUS, WIND ADVISORY
WL CONTINUE AS IS. WL HANDLE ANY DAMAGING WINDS WITH AN SPS OR
SHORT-FUSED HIGH WIND WRNG.
SEE NO REASON TO CHG HRLY T/TD VALUES AS THEY WL SLOWLY RISE
OVRNGT BFR FROPA. NO CHGS NEEDED TO THESE GRIDS ATTM.
PREV DISCO BLO...
115 PM UPDATE... MAIN CONCERN IS FOR STRONG COLD FRONT MOVING
THROUGH LATE TONIGHT WITH GUSTY WINDS...AND A POTENTIAL SQUALL
THAT COULD HAVE LOCALIZED DAMAGING GUSTS.
WELL AHEAD OF THE FRONT...STOUT SOUTHWEST FLOW IS RIDDLED WITH
SHORTWAVES WHICH HAVE ALREADY PRODUCED SOME SHOWERS OVER THE TWIN
TIERS THROUGH CENTRAL NY. SHOWERS ARE PRESSING SOUTHEAST WITH
TIME YET ALSO WITH SATURATED LAYER NOT AS DEEP SO IS BECOMING MORE
SPOTTY IN COVERAGE. ALL OF THIS OF COURSE TAKES A BACK SEAT TO THE
SET UP FOR TONIGHT.
SYNOPTICALLY SPEAKING...STRONG 850MB JET OCCURS AHEAD OF AND ALONG
FRONT OF 60-75 KTS. COMPARED TO THE WAY THE MODELS LOOKED 24 HRS
AGO...THE JET WHILE STILL STRONG IS NOT POSITIONED QUITE AS LOW
IN THE COLUMN. ALSO...MODEL SOUNDINGS ALL SUGGEST NEAR SURFACE AIR
WILL NOT BE CONDUCIVE FOR MIXING DOWN STRONG GUSTS. UNTIL THE
FRONT COMES...HIGHEST GUSTS WILL BE LIMITED MAINLY TO RIDGETOPS IN
CENTRAL NY. IN COORDINATION WITH ADJOINING NWS OFFICES I HAVE
ELECTED TO REPLACE THE HIGH WIND WATCH WITH A WIND ADVISORY /PLUS
A FEW MORE ZONES/...GIVEN EXPECTATION THAT PEAK GUSTS STAYING
BELOW 50 MPH. ANYTHING HIGHER SHOULD BE LIMITED TO THE POTENTIAL
SQUALL IMMEDIATELY ALONG THE FRONT ITSELF...AS HINTED AT BY SPC
SLIGHT RISK FOR SEVERE THUNDERSTORMS FOR OUR WHOLE AREA. THIS
SHORT-FUSE POSSIBILITY WILL BE HANDLED VIA SPS/SVR IF NECESSARY.
CONFIDENCE HAS INCREASED ON TIMING OF FRONT OVERNIGHT...WITH
SQUALL PASSING THROUGH DURING 05Z-10Z TIME FRAME. LOW TOPPED LINE
EXPECTED WITH LIMITED IF ANY LIGHTNING...BUT CONVECTIVE
NONETHELESS AND CAPABLE OF MIXING DOWN STRONG GUSTS. CONDITIONS
MORE FAVORABLE UPSTREAM...BUT STRONGLY FORCED FRONT WILL STILL
CARRY EAST FROM THERE WITH GOOD GUSTS...THE ONLY QUESTION IS HOW
STRONG. 925-850MB JET WILL BE DECREASING JUST AS FRONT CARRIES
THROUGH THE REGION. ALL-IN-ALL AN EERIE WARM EVENING FOLLOWED BY
AN ACTIVE PERIOD MIDNIGHT ONWARD. FORECAST DETAILS HAVE BEEN
UPDATED TODAY THROUGH TONIGHT...INCLUDING SPECIFIC TIMING FOR
CONVECTIVE LINE...AND QUIRKY VERY MILD NON-DIURNAL TEMPERATURES.
POST-FRONTAL ENVIRONMENT MONDAY WILL CONTINUE TO FEATURE GUSTY
WINDS...THIS TIME JUST FROM PRESSURE GRADIENT. ADVISORY LEVEL
GUSTS STILL PROBABLE FOR MUCH OF CENTRAL NY AND PERHAPS HIGHER
ELEVATIONS OF TWIN TIERS/CATSKILLS. FARTHER SOUTHEAST...25 TO 35
MPH GUSTS. WITH WINDS FROM 250-ISH DIRECTION AND 850MB
TEMPERATURES ONLY DIPPING TO ZERO AND FIVE BELOW CELSIUS BY LATE
MONDAY AFTERNOON...AT LEAST FOR DURING THE DAY I AM ONLY EXPECTING
SPOTTY RAIN SHOWERS REACHING INTO CENTRAL SOUTHERN TIER FROM LAKE
ERIE...AND RAIN SHOWERS DEVELOPING NORTH OF THE NY THRUWAY FROM
LAKE ONTARIO.
NON-DIURNAL TEMPERATURES THROUGH THE PERIOD...INCLUDING VERY MILD
CONDITIONS TONIGHT AND THEN STEADY OR FALLING ON MONDAY DUE TO
STRONG COLD AIR ADVECTION.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
SOME LAKE EFFECT
PRECIPITATION WILL LIKELY BE OCCURRING SOUTHEAST LAKE ONTARIO
MONDAY NIGHT. 850 MB TEMPERATURES START OUT AROUND -5 C EARLY IN
THE EVENING AND FALL TO -8 TO -10 BY TUESDAY MORNING. PRECIPITATION
EARLY TUESDAY EVENING WILL LIKELY BE A MIX OF RAIN AND SNOW
SHOWERS EAST OF LAKE ONTARIO... TRENDING TOWARD SNOW OVERNIGHT. BOUNDARY
TEMPERATURES WILL BE MARGINAL FOR ACCUMULATIONS... ESPECIALLY AT
LOWER ELEVATIONS. THE FLOW WILL BE FROM AROUND 290 EARLY IN THE
NIGHT SHIFTING TO AROUND 310 BY TUESDAY MORNING. BASED ON THIS
HAVE GONE WITH LIKELY POPS ACROSS OUR NORTHERN COUNTIES MONDAY
EVENING... THEN CHC POPS SPREADING SOUTH TOWARD THE SOUTHERN TIER OF
NY OVERNIGHT. WITH TEMPERATURES MARGINALLY COLD ENOUGH FOR SNOW
AND SHIFTING WINDS AM NOT EXPECTING A MAJOR EVENT... BUT SOME
SMALL ACCUMULATIONS COULD OCCUR ESPECIALLY AT ELEVATIONS ABOVE
1000 FEET ABOVE SEA LEVEL.
SCATTERED LIGHT SNOW SHOWERS MAY CONTINUE INTO TUESDAY MORNING
WITH A 310-320 FLOW FAVORING AREAS DOWNSTREAM OF THE FINGER
LAKES... HOWEVER WITH TEMPERATURES ONLY MARGINALLY COLD ENOUGH FOR
LAKE EFFECT SNOW AND MOISTURE RAPIDLY DECREASING EXPECT ONLY
MINOR IF ANY ACCUMULATIONS ON TUESDAY. HIGH PRESSURE WIL BUILD ACROSS THE
AREA BRINGING DRY SEASONABLY COOL WEATHER TUESDAY NIGHT INTO
WEDNESDAY.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
GFS AND ECMWF ARE IN GENERALLY GOOD AGREEMENT ON THE EVOLUTION OF
THE PATTERN LATE NEXT WEEK ALTHOUGH WITH THE USUAL TIMING AND
INTENSITY DIFFERENCES THAT ARE OFTEN SEEN AT THAT TIME RANGE.
THURSDAY SHOULD BE DRY AND MILD WITH HIGH PRESSURE MOVING OFF THE EAST
COAST. CHANCE OF SHOWERS WILL INCREASE FRIDAY AND SATURDAY AS THE
NEXT COLD FRONT APPROACHES FROM THE WEST. BEST CHANCE FOR
PRECIPITATION APPEARS TO BE SATURDAY AS A COLD FRONT MOVES ACROSS
THE AREA. AT THIS POINT THE MOST LIKELY P-TYPE WITH THIS SYSTEM
APPEARS TO BE RAIN BUT SOME MIX MAY OCCUR IF SOME OF THE COOLER
LONG-RANGE SOLUTIONS WERE TO VERIFY. COLD WEATHER WILL RETURN ON
SUNDAY WITH BOTH THE GFS AND ECMWF ADVERTISING THE COLDEST WEATHER
OF THE SEASON BY EARLY NEXT WEEK.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
06Z UPDATE...
SCATTERED RAIN SHOWERS ARE SLOWLY MOVING ACROSS CENTRAL NEW YORK
AND NORTHEAST PENNSYLVANIA THIS MORNING. THESE SHOWERS ARE A MIX
OF VFR AND MVFR CIGS WITH EMBEDDED IFR CIGS. VISBYS MAY FALL TO
IFR AT KBGM FOR A BRIEF PERIOD OF TIME BUT ARE NOT EXPECTED AT
REMAINING TAF SITES. GUSTY WINDS UP TO 35 KNOTS ARE POSSIBLE WITH
THESE SHOWERS. THESE SHOWERS ARE EXPECTED TO CONTINUE FOR THE NEXT
COUPLE OF HOURS AHEAD OF AN APPROACHING COLD FRONT. BEHIND THE
COLD FRONT AN ABRUPT WIND SHIFT WILL OCCUR AND GUSTY WINDS WILL
FOLLOW. WINDS ARE EXPECTED TO BE SUSTAINED AT 20 KNOTS THROUGH THE
AFTERNOON/EVENING ON MONDAY.
COOLER AND DRIER AIR WILL FUNNEL IN THE REGION MONDAY AFTERNOON
BRINGING A CHANCE FOR LAKE EFFECT RAIN SHOWERS TO KRME LATER IN
THE DAY. THESE SHOWERS WILL DEVELOP AROUND 03Z TUESDAY MORNING AND
CONSIST OF MVFR CIGS.
OUTLOOK...
MON AFTN THRU TUE MRNG...MVFR POSSIBLE IN SNOW SHOWERS...MAINLY SYR
AND RME MON NGT AND PERHAPS ALSO KITH-KBGM TUE MRNG.
WED/THU...VFR.
FRI...POSSIBLE RESTRICTIONS FROM -SHRA.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR PAZ038.
NY...WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR NYZ009-015>018-
022>025-036-037-044>046-055-056.
&&
$$
SYNOPSIS...MDP/PVN
NEAR TERM...MDP/PVN
SHORT TERM...MSE
LONG TERM...MDP/MSE
AVIATION...KAH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1250 AM EST MON NOV 18 2013
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION FROM THE WEST EARLY THIS MORNING.
HIGH PRESSURE WILL BUILD INTO THE CAROLINAS FROM THE NORTHWEST THIS
AFTERNOON AND INFLUENCE OUR WEATHER THROUGH WEDNESDAY.
&&
.NEAR TERM /OVERNIGHT/...
AS OF 945 PM SUNDAY...
OVERVIEW:
A NEGATIVELY TILTED UPPER LEVEL TROUGH AND ATTENDANT SFC LOW OVER
THE GREAT LAKES WILL TRACK NORTHEAST INTO ONTARIO/QUEBEC...WHILE AN
ASSOCIATED COLD FRONT PROGRESSES RAPIDLY EAST THROUGH THE SOUTHERN
APPALACHIANS INTO CENTRAL/WESTERN PORTIONS OF THE MID-ATLANTIC AND
CAROLINAS BY 12Z MON.
PRECIPITATION CHANCES:
SCATTERED SHOWER ACTIVITY ASSOCIATED WITH WARM ADVECTION AND
MARGINAL ELEVATED INSTABILITY DOWNSTREAM OF THE APPROACHING
LOW-LEVEL TROUGH /COLD FRONT/ OVER THE TN VALLEY WILL WEAKEN SHORTLY
AFTER 06Z AS LOW-LEVEL FLOW VEERS TO A MORE WESTERLY DIRECTION AND A
DRIER MID-LEVEL AIRMASS (PER 00Z UPSTREAM RAOB DATA SUCH AS KOHX)
BEGINS TO ADVECT INTO THE REGION. ASIDE FROM THE POTENTIAL FOR A
SMALL AMPLITUDE DISTURBANCE IN WSW FLOW ALOFT...ANTICIPATE LITTLE IN
THE WAY OF UPPER LEVEL FORCING AS THE AMPLIFYING UPPER LEVEL WAVE
OVER THE GREAT LAKES TRACKS FURTHER AWAY FROM THE REGION INTO
CANADA. WITH THE ABOVE IN MIND...EXPECT SCATTERED ELEVATED SHOWER
ACTIVITY TO PERSIST THROUGH ~06Z. THEREAFTER...A SHORT LULL IN
ACTIVITY MAY BE POSSIBLE BEFORE CHANCES INCREASE ONCE AGAIN IN
ASSOC/W A NARROW SW-NE ORIENTED LINE OF LOW-TOPPED CONVECTION
EXPECTED TO PROGRESS INTO WESTERN PORTIONS OF THE AREA BY 12Z AS THE
COLD FRONT /LOW-LEVEL TROUGH/ APPROACH.
THUNDERSTORM POTENTIAL:
RECENT REMOTE SENSING DATA INDICATED A FEW ISOLD LIGHTNING STRIKES
IN UPSTATE SC WHERE LOW-LEVEL WARM ADVECTION AND ELEVATED
INSTABILITY ARE PRESUMABLY STRONGER...AS SUGGESTED BY 01Z SPC
MESOANALYSIS DATA. AN ISOLD LIGHTNING STRIKE CANNOT BE RULED OUT
WITH ELEVATED SHOWER ACTIVITY THROUGH ~06Z...PRIMARILY IN SOUTHERN
PORTIONS OF THE AREA. ALTHOUGH THE LATEST RAP MODEL DATA INDICATES
THAT STRENGTHENING SOUTHERLY FLOW WILL BEGIN TO ADVECT A MARGINALLY
UNSTABLE SURFACE BASED AIRMASS (CHARACTERIZED BY SFC DEWPOINTS IN
THE MID/UPPER 60S AND MLCAPE OF 250-500 J/KG) INTO PORTIONS OF
CENTRAL NC BY 09Z...IT SEEMS LIKELY THAT A SHALLOW NEAR-SFC STABLE
LAYER WILL REMAIN IN PLACE DUE TO PRIOR SHOWER ACTIVITY AND ONGOING
NOCTURNAL EFFECTS. THIS...IN ADDITION TO WEAK UPPER LEVEL FORCING
AND MID-LEVEL DRYING SHOULD PRECLUDE ANY POTENTIAL FOR SFC-BASED
CONVECTION /SEVERE WEATHER/ AS THE LOW-LEVEL TROUGH APPROACHES
WESTERN PORTIONS OF THE AREA BY SUNRISE.
TEMPERATURES:
AS SOUTHERLY FLOW STRENGTHENS EXPECT TEMPERATURES TO SLOWLY RISE
OVERNIGHT...INTO THE UPPER 60S TO NEAR 70F IN THE FAR S/SE AND INTO
THE MID 60S IN THE N/NW. -VINCENT
&&
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
AS OF 325 PM SUNDAY...
THE COLD FRONT IS EXPECTED TO PUSH QUICKLY EAST OF THE TRIANGLE
THROUGH THE SOUTHEAST CWA MONDAY MORNING. MUCH DRIER AIR WILL PUSH
IN QUICKLY BEHIND THE FRONT... WITH STRONG SUBSIDENCE AND CLEARING
SKIES AS SURFACE HIGH PRESSURE BUILDS IN FROM THE WEST. EXPECT A
TRANSITION FROM THICK CLOUDY SKIES RAPIDLY TO MOSTLY SUNNY SKIES...
WITH LINGERING SCATTERED CLOUDS BASED AROUND 6000 FT AGL INTO THE
AFTERNOON. THICKNESSES FALL SLOWLY THROUGH THE DAY... WITH A MUCH
MORE PRECIPITOUS DROP LATE IN THE DAY THROUGH MONDAY NIGHT... MAKING
TEMPS DIFFICULT TO PINPOINT. IN FACT.. CURRENT TEMPS IMMEDIATELY
BEHIND THE FRONT ARE STILL IN THE 70S. EXPECT HIGHS FROM 68 NW (WITH
A RISE OF UNDER 10 DEGREES THROUGH THE DAY) TO 75 SOUTHEAST. WINDS
NW AROUND 10-15 MPH. COLDER AIR RUSHES IN BY EVENING AND LASTS
THROUGH THE NIGHT... ALTHOUGH THE COLD AIR ADVECTION AND CLEAR SKIES
WILL BE TEMPERED BY THE CONTINUED MIXING OVERNIGHT. LOWS 36-42. -GIH
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
AS OF 250 PM SUNDAY...
HIGH PRESSURE WILL BUILD FROM THE MIDWEST TOWARD NEW ENGLAND TUESDAY
AND WEDNESDAY AS AN UPPER RIDGE BUILDS ALONG THE EAST COAST. THE
SURFACE HIGH IS THEN FORECAST TO PERSIST MOST OF THE
WEEK...SUPPLYING COOL AIR AND POTENTIAL COLD AIR DAMMING AS MOISTURE
BEGINS TO INCREASE FROM THE WEST-SOUTHWEST AHEAD OF A SLOW MOVING
COLD FRONT. WHILE MOST OF THE MOISTURE AND PRECIP ASSOCIATED WITH
THE SLOWING COLD FRONT SHOULD STAY WEST OF THE MOUNTAINS...MODELS
SUGGEST SOME LIGHT PRECIP MAY SPREAD ACROSS THE MOUNTAINS BY
FRIDAY...WHICH MAY HELP TO REINFORCE THE WEAK CAD PRIOR TO THE COLD
FRONT FINALLY BEING PUSHED EAST BY A STRONGER SHORTWAVE DIGGING
THROUGH THE GREAT LAKES ON SATURDAY. WILL LEAVE POPS OUT FOR
FRIDAY BUT INCLUDE A CHANCE POP ON SATURDAY. 1000-850MB THICKNESSES
BOTTOM OUT AROUND 1310M TUESDAY/WEDNESDAY MORNING...WHICH WOULD
YIELD HIGHS IN THE MID 50S AND LOWS IN THE UPPER 20S AND LOWER 30S
WEDNESDAY MORNING. WILL THEN ERR ON THE COOLER SIDE OF GUIDANCE FOR
TEMPS THURSDAY THROUGH SATURDAY...WITH HIGHS IN THE LOW TO MID 50S
WEST AND LOW TO MID 60S EAST. LOWS SHOULD BE MOSTLY IN THE UPPER
30S AND LOWER 40S.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 1250 AM MONDAY...
WIDESPREAD LIFR/IFR CONDITIONS WILL PREVAIL ACROSS CENTRAL NC
THROUGH 10-12Z AS SLY FLOW IN THE LOWER LEVELS OF THE ATMOSPHERE
MAINTAINS A WARM MOIST AIR MASS. SCATTERED SHOWERS WILL BECOME MORE
LIKELY AFTER 08Z AS A COLD FRONT MOVES INTO OUR REGION FROM THE
WEST. THE COLD FRONT SHOULD CROSS THE TRIAD TERMINALS BETWEEN
10-11Z...THE KRDU VICINITY AROUND 12Z...AND KRWI AND KFAY BETWEEN
13-14Z. THE PASSAGE OF THE FRONT WILL BE NOTED BY SURFACE WINDS
VEERING TO THE NW. AHEAD AND BEHIND THE FRONT...EXPECT SURFACE WIND
GUSTS AROUND 20KTS.
DRIER MORE STABLE AIR WILL OVERSPREAD CENTRAL NC FROM THE NW BEHIND
THE FRONT. THIS WILL INITIATE RAPID CLEARING WITH SKIES BECOMING
MOSTLY CLEAR NW-SE BETWEEN 11Z-15Z.
HIGH PRESSURE WILL BUILD INTO THE CAROLINAS THIS AFTERNOON AND
TONIGHT AND LINGER OVER THE REGION TUESDAY INTO WEDNESDAY. THIS
WEATHER SYSTEM WILL BE ACCOMPANIED BY VFR CONDITIONS.
A RETURN FLOW OF MOISTURE AND AN APPROACHING FRONTAL SYSTEM WILL
BRING THE NEXT THREAT FOR SUB-VFR PARAMETERS THURSDAY INTO
FRIDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...VINCENT
SHORT TERM...HARTFIELD
LONG TERM...SMITH
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1231 AM EST MON NOV 18 2013
.SYNOPSIS...
A COLD FRONT WILL MOVE OFF THE CAROLINA COAST TODAY AS COLD CANADIAN
HIGH PRESSURE BUILDS OVER THE REGION THROUGH THE MIDDLE OF THE WEEK.
THE NEXT COLD FRONT IS EXPECTED TO REACH OUR AREA NEXT SATURDAY.
&&
.NEAR TERM /THROUGH TODAY/...
0530 UTC UPDATE...POPS WERE ADJUSTED PER RADAR TRENDS...WITH A
DECREASE IN THE NC FOOTHILLS THE NEXT HOUR OR TWO. POPS WERE ALSO
ADJUSTED TO ACCOUNT FOR TIMING OF THE FRONTAL PASSAGE THIS MORNING.
QPF WAS ADJUSTED ACCORDINGLY...WITH A DECREASE IN THE FOOTHILLS..AND
A BIT MORE IN THE MOUNTAINS. WINDS WERE UPDATED FROM A BLENDED MODEL
DATA...PRESERVING GUSTS AT HIGH ELEVATIONS OVERNIGHT.
AS OF 920 PM...A SMALL CLUSTER OF THUNDERSTORMS WAS TRACKING ACROSS
CHESTER...SC AT 40 MPH. OTHERWISE...AREAS OF LIGHT RAIN AND HEAVY
DRIZZLE WILL REMAIN ACROSS THE FORECAST AREA THROUGH THE REST OF THE
EVENING. A THIN LINE OF ORGANIZED TSRA EXISTED ACROSS MIDDLE
KY/TN...TRACKING SE AT 35 MPH. AT THIS RATE...THE LEADING EDGE OF
THE LINE COULD REACH GRAHAM AND SWAIN COUNTIES AROUND 5Z.
HOWEVER...THE TN BORDER COUNTIES MAY THE GREATEST COVERAGE BETWEEN
5-7Z. THE LATEST RUN OF THE HRRR INDICATES THAT THE CONVECTION WILL
WEAKEN GRADUALLY ACROSS EASTERN TN...REACHING THE NC COUNTIES WILL
DECREASED REFLECTIVITY AND SHORTER LINE SEGMENTS. THE LATEST
MESOSCALE ANALYSIS INDICATES NO INSTABILITY ACROSS THE FORECAST
AREA. HOWEVER...A BAND OF WEAK VALUES OF CAPE MAY POOL ALONG AND
AHEAD OF THE CONVECTION. THE FORECAST AND HWO APPEARS ON TRACK.
AS OF 7 PM...AREAS OF RAIN AND HEAVY DRIZZLE WILL REMAIN ACROSS THE
FORECAST AREA THIS EVENING AND INTO EARLY MON MORNING. THE PRIMARY
FORECAST CONCERN WILL BE ASSOCIATED WITH THE PRE FRONTAL BAND OF
TSRA...LOCATED OVER MIDDLE AND WESTERN KY/TN. 22Z HRRR INDICATES
THAT THE BAND WILL APPROACH THE NC/TN LINE BY 7Z. THROUGH 9Z...HRRR
INDICATES THAT LINE SEGMENTS OF SHRA/TSRA WILL PUSH ACROSS THE
MTNS...TRACKING ACROSS THE NC FOOTHILLS. PRE FRONT NAM12 SHERB 0-3
KM VALUES RANGE FROM .6-.7. ALSO...0-3 KM EHI VALUES DECREASE FROM
.7-.4 M2/S2 FROM WEST TO EAST. I WOULD EXPECT THAT THE LINE OF
CONVECTION WILL CROSS THE SPINE OF THE APPALACHIANS LATE
TONIGHT...LARGELY INTACT. HOWEVER...THE ENVIRONMENT DOES NOT FAVOR
AN ORGANIZED BAND OF CONVECTION ACROSS THE THE FOOTHILLS AND
PIEDMONT. THE HWO APPEARS WELL WORDED...NO CHANGES PLANNED AT THIS
TIME. OTHERWISE...TEMPS SHOULD REMAIN NEARLY STEADY THIS EVENING AND
TONIGHT.
AS OF MID AFTERNOON...SHOWERS CONTINUE TO DEVELOP AND FILL IN ACROSS
NE GEORGIA...THE UPSTATE...AND THE NC FOOTHILLS...WHILE AN AREA OF
PRECIP MOVES ACRS THE NC MTNS FROM ERN TN. PRECIP CHANCES GRADUALLY
RAMP UP THROUGH THE REST OF THE DAYLIGHT HOURS TO ACCOUNT FOR THIS.
TEMPS ARE WARMER THAN EXPECTED ACROSS METRO CHARLOTTE...SO HIGH
TEMPS WERE RAISED THERE.
THE FIRST BATCH OF PRECIP WAS BEING DRIVEN BY THE PASSAGE OF A SHORT
WAVE...SEEN ON THE WATER VAPOR IMAGERY. THERE COULD BE A LULL IN
ACTIVITY MOVING IN FROM THE WEST THIS EVENING...ALTHO LOW LEVEL
MOISTURE AND FORCING WILL REMAIN IN PLACE. THIS DOES NOT LEAVE
ENOUGH CONFIDENCE TO TEMPORARILY LOWER THE PRECIP CHANCES AHEAD OF
THE FRONT...BUT SOME TWEAKING MIGHT BE DONE DURING THE EARLY EVENING
IF REDEVELOPMENT IS NOT SEEN. MOST SIGNS POINT TO A FRONTAL PASSAGE
DURING THE EARLY MORNING HOURS ACROSS MOST OF THE FCST AREA...WITH
THE FRONT STRETCHED OUT OVER THE PIEDMONT AT SUNRISE. THE MAIN ISSUE
IS THE SEVERE WEATHER POTENTIAL. ALTHO SHEAR WILL BE SUFFICIENT...
THE MODEL GUIDANCE CONTINUES TO FAIL TO GIVE MUCH IN THE WAY OF
INSTABILITY. ONLY THE SW MTNS GET EVEN MINIMAL AMOUNTS OF CAPE.
THUS...SOME WIND DAMAGE POTENTIAL CANNOT BE RULED OUT ON THE TN
BORDER THROUGH THE EARLY MORNING HOURS...BUT SEVERE WEATHER LOOKS
UNLIKELY ELSEWHERE. TEMPS WILL NOT FALL OFF MUCH BEFORE THE FRONT
ARRIVES...WHICH SHOULD LEAD TO AN UNSEASONALLY MILD NIGHT OVER THE
PIEDMONT.
THE FRONT SHOULD EXIT THE WESTERN PIEDMONT BY 13Z TO 14Z. A SMALL
POP WAS KEPT OVER THE EASTERN ZONES TO START THE DAY...BUT IS
QUICKLY DISPATCHED EASTWARD. EXPECT RAPID CLEARING MONDAY MORNING
BEHIND THE FRONT...BUT COOLER AIR WILL BE SLOW TO ARRIVE. DOWNSLOPE
E OF THE MTNS WILL ALLOW TEMPS TO CLIMB ABOVE NORMAL ONCE AGAIN WITH
GUSTY NW WIND IN THE AFTERNOON.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
AS OF 200 PM SUNDAY...A SPLIT QUASI-ZONAL FLOW PATTERN IS EXPECTED
IN THE UPR LVLS DURING THE SHORT TERM...WITH A SOUTHERN STREAM
SHORTWAVE TROF CROSSING THE CWFA TUESDAY NIGHT. MEANWHILE...DRY HIGH
PRES DRIFTS EAST FROM THE MIDWEST TO THE EASTERN SEABOARD BY 00Z
THURSDAY. FCST SNDGS SHOW SOME MAINLY UPR LVL MOISTURE STREAMING
ACRS THE AREA AHEAD OF THE SHORTWAVE TUESDAY EVENING. BUT IT LOOKS
VERY DRY BELOW 600 MB. SO NO PRECIP IS EXPECTED...DESPITE STRONG QG
FORCING WITH THE WAVE...JUST A PERIOD OF SOME BKN-OVC SKIES
POSSIBLE. TEMPS WILL GENERALLY BE SEVERAL DEGREES BELOW NORMAL BOTH
TUESDAY AND WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 200 EST PM SUNDAY...THE GLOBAL MODELS ARE IN FAIR AGREEMENT
WITH THE OVERALL SYNOPTIC PATTERN FOR THE MEDIUM RANGE PERIOD.
WEAK UPPER RIDGING WILL PERSIST ACROSS THE SE WED NIGHT INTO FRIDAY
AS 588 DM ANTICYCLONE BUILDS ACROSS THE GULF OF MEXICO AND SLOWLY
RETROGRADES THRU THE PERIOD. AN UPPER LOW PRESSURE TROUGH OVER SOUTH
CENTRAL CANADA ON FRI WILL THEN DIGS SOUTHEAST INTO THE GREAT LAKES
REGION FRI NIGHT...AND INTO THE SOUTHEASTERN STATES BY SAT. THE
TROUGH AXIS IS EXPECTED TO CROSS THE FORECAST AREA SUN AND OFF THE
ATLANTIC COAST BY SUN NIGHT.
AT THE SURFACE...CANADIAN HIGH PRESSURE CENTERED ACROSS NEW ENGLAND
WILL CONTINUE TO RIDGE INTO THE CWA WED NIGHT INTO
THURSDAY...ALLOWING COOL NE FLOW TO PERSIST THRU THE PERIOD. BY
FRIDAY...MOIST RETURN S/SE FLOW WILL SET UP ACROSS THE AREA AS THE
HIGH SHIFTS EAST OF THE AREA AND A COLD FRONT APPROACHES FROM THE
WEST. WITH INCREASING MOIST ISENTROPIC LIFT...POPS RAMP UP TO 20/30
PERCENT TOWARD FRI AFTERNOON. THE GFS PUSHES THE FRONT THROUGH THE
REGION FRI NIGHT INTO SAT MORNING WHILE THE SLOWER 12Z ECMWF PUSHES
IT DURING THE DAY ON SAT. BOTH THE GFS/ECMWF GENERATE ABOUT
0.25-0.5" OF QPF DURING THE FROPA. TAKING A COMPROMISE...POPS REMAIN
IN THE 30/40 PERCENT RANGE FRI NIGHT THRU EARLY SAT. CONDITIONS DRY
OUT BY SAT NIGHT AS THE FRONT PUSHES OFFSHORE AND DRY CANADIAN HIGH
BUILDS IN FROM THE WEST. TEMPERATURES WILL REMAIN 3-5 DEGREE BELOW
NORMAL THRU THURSDAY BEFORE WARMING UP TO NEAR NORMAL RANGE BY FRI.
TEMPS THEN DROP CONSIDERABLY TO 7-10 BELOW NORMAL ON SUN AS COLD
CANADIAN HIGH BUILDS IN.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AT KCLT...MODEL GUIDANCE SUPPORTS CIG FALLING FROM IFR TO LIFR OR
EVEN VLIFR BY DAYBREAK IN A MOIST AIR MASS AHEAD OF A COLD FRONT.
FOR NOW WILL ALLOW CIG TO FALL TO LIFR. VSBY SHOULD REACH MVFR AS
WELL. SHOWERS WILL ACCOMPANY THE FRONT...BUT THUNDER CHANCES ARE TOO
LOW TO MENTION. FRONTAL PASSAGE WILL BE SOME TIME AROUND DAWN...
FOLLOWED WINDS VEERING SW TO NW AND BECOMING GUSTY...WITH
RESTRICTIONS ENDING. WINDS VEER TO THE N TONIGHT AND LOSE MUCH OF
THEIR GUSTINESS.
ELSEWHERE...RESTRICTIONS WILL LOWER AS A COLD FRONT AND ITS
ASSOCIATED PRECIPITATION MOVE INTO THE AREA FROM THE WEST OVERNIGHT.
GUIDANCE HINTS AT VLIFR CIGS AT MANY SITES...BUT CONFIDENCE IS
LIMITED...AND ONLY IFR WILL BE CARRIED AT KAVL...WITH LIFR AT
FOOTHILLS SITES. GUIDANCE SUPPORTS IFR CIGS AT ALL SITES. FRONTAL
PASSAGE WILL BE BEFORE DAWN. THUNDER CHANCES ARE ONLY ENOUGH FOR A
MENTION AT KAND. WINDS WILL VEER FROM SW TO NW WITH FRONTAL PASSAGE
BEFORE DAWN...BUT SPEEDS WILL BE TOO LOW TO MIX OUT RESTRICTIONS
UNTIL AFTER DAYBREAK. NW WINDS BECOME GUSTY DURING THE DAY...THE
VEER TO THE N TONIGHT WITH GUSTS DECREASING.
OUTLOOK...VFR FROM MONDAY NIGHT THROUGH THE MIDDLE OF THE UPCOMING
WEEK.
CONFIDENCE TABLE...
05-11Z 11-17Z 17-23Z 23-05Z
KCLT LOW 55% MED 65% MED 71% HIGH 95%
KGSP MED 78% MED 76% MED 77% MED 72%
KAVL MED 78% MED 65% HIGH 84% HIGH 89%
KHKY HIGH 81% HIGH 85% MED 74% MED 74%
KGMU MED 77% MED 75% MED 76% HIGH 80%
KAND HIGH 83% MED 65% HIGH 89% HIGH 87%
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...JOH
NEAR TERM...JAT/NED/PM
SHORT TERM...ARK
LONG TERM...JOH
AVIATION...JAT
FIRE WEATHER...
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
1104 PM CST SUN NOV 17 2013
.UPDATE...
UPDATED TO INCLUDE THE 06Z AVIATION DISCUSSION BELOW.
JCL
&&
.DISCUSSION... /ISSUED 917 PM CST SUN NOV 17 2013/
LINE OF SHOWERS AND ISOLATED THUNDERSTORMS CONTINUES TO PUSH
SOUTH INTO NORTH MISSISSIPPI. SKIES ARE CLOUDY ALONG AND AHEAD OF
THIS LINE BUT BEHIND THE LINE SKIES ARE CLEAR. TEMPERATURES RANGE
FROM THE UPPER 50S TO LOWER 70S. THE LINE OF SHOWERS SHOULD MOVE
THROUGH THE REMAINDER OF THE FORECAST AREA BY MIDNIGHT. HAVE
ADJUSTED POPS FOR THE EVENING HOURS. ALSO REMOVED MENTION OF FOG
OVERNIGHT AND INTO MONDAY MORNING.
ARS
PREV DISCUSSION... /ISSUED 542 PM CST SUN NOV 17 2013/
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...
06Z TAF CYCLE (18/06Z-19/06Z)
A COLD FRONT WILL MOVE SOUTHEAST OF THE MIDSOUTH EARLY MONDAY MORNING
FOLLOWED BY MUCH DRIER AIR. AT KTUP...MVFR CONDITIONS WITH A FEW
SHOWERS AND PATCHY FOG MAY LINGER UNTIL ABOUT 07Z...OTHERWISE VFR
CONDITIONS ARE EXPECTED TO PREVAIL AT THE TAF SITES
(KMEM...KMKL...KJBR...AND KTUP) THROUGH THE PERIOD. WINDS TONIGHT
NW-N 6-7 KTS...WINDS MONDAY N 9-11 KTS...WINDS AFTER 19/00Z N-NE
4-6 KTS.
JCL
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 49 63 41 59 / 60 0 0 0
MKL 43 62 35 57 / 60 0 0 0
JBR 43 61 36 55 / 10 0 0 0
TUP 48 66 38 60 / 70 0 0 0
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
347 AM CST MON NOV 18 2013
.DISCUSSION...
DENSE FOG CONTINUES TO BLANKET MUCH OF SOUTHEAST TEXAS THIS
MORNING. A WEAK COLD FRONT IS DRAPED ACROSS THE EXTREME NORTHERN
PART OF THE CWA AND IS DRIFTING SLOWLY SOUTH. AM EXPECTING A
GRADUAL IMPROVEMENT IN VISIBILITY OVER THE NORTH AS DRIER AIR
FILTERS INTO THE REGION. CROCKETT HAS ALREADY CLEARED OUT BUT
HUNTSVILLE IS STILL BELOW A 1/2 MILE. THE FRONT WILL MOVE THROUGH
SE TX TODAY BUT THE SLOW MOVEMENT WILL ALLOW FOGGY CONDS TO
PREVAIL ALONG THE COAST THROUGH LATE MORNING. WILL ADJUST THE
DENSE FOG ADVISORY RIGHT BEFORE SENDING THE ZFP TO TRY AND MATCH
UP WITH CURRENT OBS. THE BOUNDARY COULD ALSO TRIGGER A FEW SHOWERS
AS IT ENCOUNTERS DEEP MOISTURE CLOSER TO THE COAST. SATELLITE
DERIVED PW VALUES ARE NEAR 2.0 INCHES ALONG THE COAST AND THE RAP
AND HRRR WANT TO DEVELOP PRECIP ALONG THE BOUNDARY LATER THIS
MORNING. WILL MAINTAIN CHC/SLT CHC POPS FOR AREAS GENERALLY EAST
OF I-69.
TUESDAY LOOKS QUIET BUT MOISTURE BEGINS TO RETURN ON WEDNESDAY.
PWATS INCREASE TO 1.6 INCHES ON WED AND NAM 12 FCST SOUNDINGS SHOW
A DEEP SATURATED LAYER BETWEEN 900-600 MB. THE GFS IS LESS
AGGRESSIVE BUT STILL SHOWS A SATURATED LAYER BETWEEN 950-700 MB.
WILL MAINTAIN SLT RAIN CHANCES FOR MAINLY THE SW HALF OF THE
REGION. A WARM FRONT WILL MOVE ACROSS SE TX WED NITE AND THURSDAY.
SOME LIGHT RAIN WILL ACCOMPANY THE FRONT AS IT MOVES NORTH. A
WEAK UPPER LEVEL DISTURBANCE COUPLED WITH DEEPER MOISTURE WILL
YIELD A CHANCE OF SHOWERS ON THURSDAY.
MODELS IN BETTER AGREEMENT WITH THE TIMING AND STRENGTH OF THE NEXT
COLD FRONT. THE ECMWF IS STILL FASTER THAN THE GFS. THE GFS IS
TRENDING A BIT FASTER AND THE ECMWF IS TRENDING A BIT SLOWER SO
THE TIMING OF THE FROPA SHOULD BE DURING THE DAY ON FRIDAY. PWATS
INCREASE TO 1.8 INCHES AHEAD OF THE FRONT. JET DYNAMICS ARE
LACKING A BIT BUT THE FRONT SHOULD SERVE AS A CATALYST FOR
SHRA/TSRA. WILL MAINTAIN HIGH END CHC POPS FOR NOW. CONSIDERABLY
COLDER TEMPERATURES WILL MOVE INTO SE TX FOR THE WEEKEND.
ISENTROPIC UPGLIDE SHOULD PERSIST INTO SATURDAY MORNING AS SW
WINDS ALOFT OVERRIDE N-NE SFC WINDS. PRECIP SHOULD END ON SAT AFTN
AS A STRONG UPPER LOW OVER BAJA RETROGRADES SLIGHTLY AND THIS WILL
ALLOW WEAK RIDGING TO AMPLIFY OVER DEEP SOUTH TEXAS. AS A
RESULT...UPPER LEVEL WINDS BRIEFLY BECOME WEST AND END THE
ISENTROPIC LIFT. IT WILL REMAIN UNSEASONABLY COLD THROUGH THROUGH
THE WEEKEND. THE UPPER LOW WILL BEGIN TO MOVE EAST ON MONDAY AND
SW WINDS ALOFT REDEVELOP. THE UPPER LOW WILL MOVE ACROSS THE STATE
NEXT TUES AND A COASTAL LOW WILL DEVELOP OFF CORPUS. THE TWO
FEATURES SHOULD BRING A GOOD CHANCE OF RAIN TO THE REGION NEXT
TUESDAY. 43
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 77 53 71 54 74 / 10 10 10 10 10
HOUSTON (IAH) 78 54 71 56 74 / 20 10 10 10 20
GALVESTON (GLS) 78 62 69 63 74 / 30 10 10 10 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...DENSE FOG ADVISORY UNTIL 9 AM CST THIS MORNING FOR THE FOLLOWING
ZONES: AUSTIN...BRAZORIA...BRAZOS...BURLESON...CHAMBERS...
COLORADO...FORT BEND...GALVESTON...GRIMES...HARRIS...
HOUSTON...JACKSON...LIBERTY...MADISON...MATAGORDA...
MONTGOMERY...POLK...SAN JACINTO...TRINITY...WALKER...
WALLER...WASHINGTON...WHARTON.
GM...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR THE FOLLOWING ZONES:
GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT OUT 20 NM.
&&
$$
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1223 AM EST MON NOV 18 2013
.SYNOPSIS...
COLD FRONT WILL MOVE OVER THE AREA THROUGH THE NIGHT...AND EXIT
EAST BY MONDAY MORING. COLD HIGH PRESSURE SETTLES OVER THE GREAT
LAKES TUESDAY AND WEDNESDAY BRINGING DRIER WEATHER INTO THE MIDDLE
OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 1055 PM EST SUNDAY...
COLD FRONT THIS EVENING LIES PITTSBURGH PA TO HUNTINGTON WV
SOUTHWEST TO NASHVILLE TN. RADAR SHOWING DISTINCT LINE OF
CONVECTION APPROACHING OUR SOUTHEAST WV COUNTIES BUT MARGINAL
INSTABILITY IN THIS AREA SHOULD KEEP THE WINDS AT JUST BELOW SVR
LEVELS...ALTHOUGH CANNOT RULE OUT AN ISOLATED TREE BEING BLOWN
DOWN ACROSS THE HIGHER ELEVATIONS OF WESTERN GREENBRIER. AS YOU
HEAD FURTHER EAST THE AIRMASS REMAINS WEDGED IN AND STABLE. THIS
WILL ACT TO KEEP THE HIGHER GUSTS ABOVE THE SURFACE...WITH SOME
HIGHER RIDGES ABOVE 3000-4000 FT GETTING SOME GUSTS TO 50 MPH.
WIND ADVISORY STILL LOOKS GOOD...SO NO CHANGES PLANNED HERE.
FOLLOWED THE 23Z HRRR AS WE HEAD THROUGH THE NIGHT WHICH INDICATES
THE LINE GRADUALLY LOSING ITS PUNCH AND ORGANIZATION ONCE IT GETS
TO ABOUT INSTERSTATE 81 AND THE BLUE RIDGE. WILL MAINTAIN A POP
CONFIGURATION OF LIKELY/CAT WITH THE LINE BUFFERED BY CHANCE
EITHER SIDE...THEN DRYING IT OUT FAST BY MORNING...AS STRONG WNW
AND SUBSIDENCE KICKS IN. TEMPS SEEM ON TARGET FOR LOWS...WHICH
WILL BE ELEVATED PER WIND AND CLOUDS.
PREVIOUS VALID DISCUSSION ISSUED AT 345 PM....
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 /TONIGHT 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 /05Z MONDAY THROUGH FRIDAY/...
AS OF 1215 AM EST MONDAY...
LINE OF SHOWERS WITH GUSTY WINDS WILL BE EAST OF BLF/LWB AT TAF
START TIME...REACHING BCB/ROA AT 06Z. RADAR INDICATES SOME HEAVIER
DOWNPOURS POSSIBLE AT BCB WITH GUSTS TO 30 KNOTS...AND HAVE A
TEMPO GROUP HERE. THE LATEST HIGH RES MODELS INDICATED THAT THE
LINE WEAKENS EAST OF THE BLUE RIDGE SO LYH/DAN IS EXPECTED TO SEE
SOME SHOWERS BUT OVERALL NO HEAVY RAIN ISSUES. UNTIL THE FRONT
PASSES...LOOKING AT BELOW 3KFT CIGS AND AS LOW AS 1KFT ALONG THE
RIDGES...BUT KEPT IT ABOVE FOR NOW. WINDS SHIFT FROM SOUTHWEST TO
WEST-NORTHWEST AT BLF/LWB 07-08Z...BCB/ROA 08-09Z...AND LYH/DAN
10-11Z.
ONCE THE FRONT MOVES BY CIGS RISE TO VFR AND SCATTER OUT. LOOK FOR
VFR TO PERSIST THROUGH THE DAY MONDAY. WIND STAYS GUSTY THROUGH
THE DAY SUBSIDING FOR SOME AROUND DUSK.
WINDS WILL BE GUSTY TOMORROW FROM THE WNW WITH SOME REACHING 30
KNOTS...MAINLY AT THE AIRPORTS LIKE KGEV/KHSP.
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 350 PM 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 EARLY THIS MORNING FOR VAZ007-019-
020-024-035.
NC...NONE.
WV...WIND ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR WVZ042-043-
045.
&&
$$
SYNOPSIS...AMS/WP
NEAR TERM...AMS/WP
SHORT TERM...KM
LONG TERM...RCS
AVIATION...AMS/WP
FIRE WEATHER...AMS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1108 PM EST SUN NOV 17 2013
.SYNOPSIS...
COLD FRONT WILL MOVE OVER THE AREA THROUGH THE NIGHT...AND EXIT
EAST BY MONDAY MORING. 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 1055 PM EST SUNDAY...
COLD FRONT THIS EVENING LIES PITTSBURGH PA TO HUNTINGTON WV
SOUTHWEST TO NASHVILLE TN. RADAR SHOWING DISTINCT LINE OF
CONVECTION APPROACHING OUR SOUTHEAST WV COUNTIES BUT MARGINAL
INSTABILITY IN THIS AREA SHOULD KEEP THE WINDS AT JUST BELOW SVR
LEVELS...ALTHOUGH CANNOT RULE OUT AN ISOLATED TREE BEING BLOWN
DOWN ACROSS THE HIGHER ELEVATIONS OF WESTERN GREENBRIER. AS YOU
HEAD FURTHER EAST THE AIRMASS REMAINS WEDGED IN AND STABLE. THIS
WILL ACT TO KEEP THE HIGHER GUSTS ABOVE THE SURFACE...WITH SOME
HIGHER RIDGES ABOVE 3000-4000 FT GETTING SOME GUSTS TO 50 MPH.
WIND ADVISORY STILL LOOKS GOOD...SO NO CHANGES PLANNED HERE.
FOLLOWED THE 23Z HRRR AS WE HEAD THROUGH THE NIGHT WHICH INDICATES
THE LINE GRADUALLY LOSING ITS PUNCH AND ORGANIZATION ONCE IT GETS
TO ABOUT INSTERSTATE 81 AND THE BLUE RIDGE. WILL MAINTAIN A POP
CONFIGURATION OF LIKELY/CAT WITH THE LINE BUFFERED BY CHANCE
EITHER SIDE...THEN DRYING IT OUT FAST BY MORNING...AS STRONG WNW
AND SUBSIDENCE KICKS IN. TEMPS SEEM ON TARGET FOR LOWS...WHICH
WILL BE ELEVATED PER WIND AND CLOUDS.
PREVIOUS VALID DISCUSSION ISSUED AT 345 PM....
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 /04Z MONDAY THROUGH FRIDAY/...
AS OF 635 PM EST SUNDAY...
SIGNIFICANT CHANGES WILL BE OCCURRING DURING THE TAF PERIOD.
WEDGE STILL HOLDING DOWN CIGS/VSBYS ACROSS THE FOOTHILLS/PIEDMONT.
MOST AREAS WILL BE SEEING OFF AND ON -SHRA WITH AT TIMES MODERATE
SHOWERS THIS EVENING AHEAD OF THE FRONT. IN THE WEST THERE SHOULD
BE SOME LOWERING OF CIGS AS MORE SHOWERS MOVE IN...SO THE VFR
THERE SHOULD BE SHORT LIVED.
THINK PREVIOUS FORECAST HAD THINGS WELL IN HAND WITH TIMING OF THE
FRONT AND THE WIND SHIFT FROM SOUTH TO SOUTHWEST TO WEST. LOOK FOR
BLF/LWB TO GET THE MAIN THRUST OF THE FRONT AROUND 06-08Z...WITH
WINDS GUSTING WITH THE BAND OF SHOWERS. THE GUSTY WINDS WITH THE
SHOWERS WILL MAKE IT INTO BCB/ROA BY 08Z...AND OUT EAST TOWARD
MORNING...ALTHOUGH SOME THINKING THAT THE STRENGTH WILL BE
LESSENED AS CORE OF LOW LVL JET WORKS NORTH OF THE AREA.
SO OVERALL KEEPING TAFS IN THE MVFR OR WORSE RANGE UNTIL OR
SHORTLY AFTER FROPA...THEN SHOULD CLEAR OUT AT LEAST EAST OF THE
BLF/LWB SECTIONS BY 12-14Z...WHILE UPSLOPE BKN VFR CIGS LINGER AT
BLF/LWB UNTIL 14-18Z.
WINDS WILL BE GUSTY TOMORROW FROM THE WNW WITH SOME REACHING 30
KNOTS...MAINLY AT THE AIRPORTS LIKE KGEV/KHSP.
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 350 PM 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/WP
NEAR TERM...AMS/WP
SHORT TERM...KM
LONG TERM...RCS
AVIATION...AMS/WP
FIRE WEATHER...AMS
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
948 AM EST MON NOV 18 2013
.UPDATE...
FRONT CONTINUING TO MOVE RAPIDLY THROUGH THE CWA. IT HAS NOW CLEARED
MCN AND CSG. SCATTERED SHOWERS THAT HAD OCCURRED ALONG THE FRONT
HAVE DISSIPATED. THERE COULD BE A FEW SHOWERS DEVELOP AHEAD OF THE
FRONT BEFORE IT PUSHES OUT OF THE CWA AROUND NOON AND HAVE LEFT LOW
CHANCE POPS FOR THE EXTREME SOUTHEAST CORNER OF THE CWA UNTIL NOON.
HAVE TAKEN POPS OUT OF THE FORECAST FOR THIS AFTERNOON AND EVENING
AS DRIER AND MORE STABLE AIR SPREADS ACROSS THE CWA. FORECAST TEMPS
LOOK ON TRACK AS WE ARE GETTING A GOOD REBOUND ACROSS NORTH GA.
LATEST PROGS SHOW THE CAA MOVING INTO THE STATE TONIGHT.
&&
.SHORT TERM /TODAY THROUGH TONIGHT/...
/ISSUED 413 AM EST MON NOV 18 2013/
AT THE SURFACE...COLD FRONT MOVING THROUGH WILL BRING SHOWERS ALONG
AND AHEAD OF IT THROUGH EARLY TO MIDDAY MONDAY ENDING FROM NORTH TO
SOUTH AS IT MOVES THROUGH. ALOFT...MAIN UPPER LEVEL ENERGY
RESPONSIBLE FOR THE SEVERE OUTBREAK ON SUNDAY ACROSS THE OHIO VALLEY
REGION IS MOVING THROUGH THE GREAT LAKES AND AWAY FROM OUR REGION.
END RESULT IS GENERALLY ZONAL FLOW IN THE MID AND UPPER LEVELS
ACROSS THE SOUTHEAST U.S. WITH SURFACE HIGH PRESSURE BUILDING IN
BEHIND THE FRONT. HAVE KEPT HIGH POPS IN WITH THE FRONT AS IT
PROGRESSES SOUTH AND EAST BUT TAPER THEM OFF QUICKLY BEHIND. HAVE
ALSO REMOVED ALL MENTION OF THUNDER AS INSTABILITY IS ALL BUT GONE.
MAIN CONCERN WITH THE FRONT IS GUSTY WINDS WITH THE SHOWERS MIXING
SOME OF THE STRONG WINDS OFF THE SURFACE DOWN. VAD WINDS SHOWING 20
TO 30 KTS IN THE LOWEST FEW THOUSAND FEET. HAVE ALREADY SEEN SOME
GUSTS TO NEAR 40 MPH ACROSS NORTH GA WITH SOME OF THE SHOWERS.
WINDS WILL PICK UP THROUGH THE DAY AS THE CLEARING LINE PROGRESSES
THROUGH THE REGION AND THE SURFACE RIDGE BUILDS IN.
OTHERWISE...THE REMAINDER OF THE SHORT TERM FORECAST LOOKS GOOD.
USED A MODEL BLEND FOR MOST ELEMENTS...WITH THE RUC AND HRRR IN THE
IMMEDIATE SHORT TERM.
30
.LONG TERM /TUESDAY THROUGH SUNDAY/...
/ISSUED 413 AM EST MON NOV 18 2013/
QUIET WEATHER IS ON TAP FOR MOST OF THE LONG TERM PERIOD. A COLD
FRONT IS EXPECTED TO IMPACT THE CWFA LATE IN THE WEEK/EARLY PART OF
THE WEEKEND...BRINGING THE NEXT BEST CHANCES FOR PRECIPITATION.
HIGH PRESSURE WILL CONTINUE ACROSS THE SE US THROUGH WEDNESDAY
BEFORE BEGINNING TO SHIFT EASTWARD ON THURSDAY. A COLD FRONT WILL
MOVE INTO THE MISSISSIPPI RIVER VALLEY ON FRIDAY. THE FRONT IS
EXPECTED TO MOVE THROUGH THE CWFA ON SATURDAY...WITH HIGH PRESSURE
RETURNING FOR THE REMAINDER OF THE WEEKEND INTO THE EARLY PART OF
NEXT WEEK.
PRECIP CHANCES WILL BEGIN TO INCREASE LATER ON THURSDAY AS MOISTURE
BEGINS TO INCREASE AHEAD OF THE APPROACHING FRONTAL BOUNDARY. THE
FRONT IS STILL PROGGED TO COME THROUGH DURING THE DAY ON
SATURDAY...WITH THE MODELS INDICATING SOME MARGINAL INSTABILITY AT
THIS TIME. WILL KEEP THE MENTION OF THUNDER.
STRONG HIGH PRESSURE WILL BUILD BEHIND THE FRONTAL BOUNDARY...AND
BREEZY/WIND CONDITIONS ARE POSSIBLE SATURDAY NIGHT INTO SUNDAY. IN
ADDITION...A COLDER AND DRIER AIRMASS WILL SETTLE OVER THE SOUTHERN
STATES.
NLISTEMAA
&&
.AVIATION...
12Z UPDATE...
COLD FRONT EXTENDING FROM CSG TO MCN AT 12Z WILL CONTINUE MOVING
SOUTH THROUGH THE AREA. WIND SHIFT TO THE NW ASSOCIATED WITH THE
FRONT AS WELL AS AN END TO ANY IFR CIGS. WILL MAINTAIN SOME MVFR
CIGS FOR A COUPLE HOURS BEHIND THE FRONT BEFORE GOING VFR AREAWIDE
BY 18Z. WITH THE COLD AIR FILTERING IN...IS POSSIBLE FOR SOME CU
EARLY THIS AFTERNOON...BUT CONFIDENCE IS LOW. GUSTY NORTHWEST
WINDS IN STORE THIS AFTERNOON AT ALL TAF SITES BEFORE RELAXING A
BIT AFTER SUNSET.
//ATL CONFIDENCE...12Z UPDATE...
MEDIUM CONFIDENCE ON TIMING OF CIG HEIGHT CHANGES.
HIGH CONFIDENCE ALL OTHER ELEMENTS.
30
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 72 46 59 36 / 20 0 5 0
ATLANTA 71 47 59 38 / 30 0 0 5
BLAIRSVILLE 66 38 56 32 / 20 0 0 0
CARTERSVILLE 69 42 58 36 / 30 0 0 0
COLUMBUS 77 53 64 41 / 70 0 5 5
GAINESVILLE 68 45 57 36 / 20 5 0 0
MACON 78 50 62 38 / 60 5 5 5
ROME 68 43 58 36 / 20 0 0 5
PEACHTREE CITY 73 45 60 37 / 30 0 5 5
VIDALIA 80 55 63 41 / 50 10 5 5
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...30
LONG TERM....NLISTEMAA
AVIATION...30
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
935 AM EST MON NOV 18 2013
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH LATE THIS AFTERNOON AND EARLY THIS
EVENING...FOLLOWED BY HIGH PRESSURE BUILDING FROM THE NORTH
THROUGH THE END OF THE WORK WEEK. ANOTHER COLD FRONT WILL MOVE
ACROSS THE REGION SATURDAY AND SATURDAY NIGHT...WITH HIGH PRESSURE
RETURNING INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SATELLITE AND SURFACE OBSERVATIONS SHOW THE COLD FRONT MOVING
SLOWLY EAST THROUGH THE MIDLANDS...CSRA AND CENTRAL GEORGIA. THE
FRONT IS EXPECTED TO SLOW DOWN OVER THE NEXT FEW HOURS ONLY TO
ACCELERATE OFFSHORE THIS EVENING AS SHORTWAVE ENERGY PASSES TO THE
NORTH. IN THE MEANTIME...THE ENTIRE FORECAST AREA LOOKS TO REMAIN
WELL EMBEDDED WITHIN THE PRE-FRONTAL WARM SECTOR THROUGH THE
AFTERNOON WITH WARM...MOIST CONDITIONS CONTINUING. DESPITE
EXTENSIVE CLOUD COVER...ONGOING WARM AIR ADVECTION WILL PUSH
HIGHS INTO THE UPPER 70S TO AROUND 80 FOR MOST LOCATIONS. SHOWER
ACTIVITY AHEAD OF THE FRONT HAS BEEN STEADILY DIMINISHING WITH
TIME AS MID-LEVEL DRY AIR OVERSPREADS THE AREA. THE BEST CHANCES
FOR MEASURABLE RAINFALL WILL REMAIN ACROSS THE FAR SOUTHERN ZONES
CLOSER TO THE ALTAMAHA RIVER. WILL CONTINUE TO HIGHLIGHT 40-50
PERCENT POPS IN THESE AREAS WITH 20-30 PERCENT POPS ELSEWHERE.
THERE WILL BE A SMALL WINDOW FOR SOME TSTM ACTIVITY THIS AFTERNOON
AS RAP INSTABILITY PROGS SHOW SBCAPE REACHING AS HIGH AS 1500 J/KG
WITH AS MUCH AS 30 KT OF 0-6 KM BULK SHEAR. THIS MAY SUPPORT A STRONG
TSTM OR TWO...BUT THE OVERALL SEVERE RISK LOOKS PRETTY LOW AT THIS
POINT.
COASTAL WEBCAMS STILL SHOW AREAS OF DENSE SEA FOG IMPACTING THE
BEACHES OF CHARLESTON COUNTY WHERE VISIBILITIES HAVE BEEN AS LOW
AS 1/4 MILE AT TIMES. THE FOG IS NOT WIDESPREAD ENOUGH TO JUSTIFY
A DENSE FOG ADVISORY...BUT THE RISK FOR REDUCED VISIBILITIES WILL
REMAIN ALONG THE BEACHES FOR MUCH OF THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
TONIGHT...THE COLD FRONT SHOULD CLEAR THE COAST BY
MIDNIGHT...LATEST ACROSS SOUTHEAST GEORGIA...WITH STRONG HIGH
PRESSURE MOVING IN FROM THE NORTHWEST AFTER MIDNIGHT. THIS WILL
LEAD TO RAPID DRYING AND INCREASING NORTH WINDS...ESPECIALLY NEAR
THE COAST.
THE SYNOPTIC PATTERN IN THE MID-WEEK PERIOD WILL BE DOMINATED BY A
NEARLY ZONAL FLOW ALOFT...WITH WEAK RIDGING STARTING TO BUILD ON
THURSDAY. MEANWHILE AT THE SURFACE...HIGH PRESSURE WILL BUILD INTO
THE REGION FROM THE NORTH AS THE CENTER DRIFTS FROM THE OHIO VALLEY
ON TUESDAY...TO OVER NEW ENGLAND ON WEDNESDAY...THEN TO A POSITION
NEAR OR JUST OFF THE NEW ENGLAND COAST ON THURSDAY.
STRONG SUBSIDENCE AND A LACK OF DEEP MOISTURE SHOULD KEEP CONDITIONS
RAIN-FREE ACROSS THE AREA...WITH THE EXCEPTION OF PORTIONS OF THE
IMMEDIATE SOUTHEAST GEORGIA COAST WHERE A NORTHEAST FLOW COULD ALLOW
ISOLATED SHOWERS TO ADVECT ONSHORE WEDNESDAY AND WEDNESDAY NIGHT.
EXPECT A GOOD AMOUNT OF SUNSHINE ON TUESDAY DESPITE SOME JET
CIRRUS...BUT INCREASING LOW LEVEL MOISTURE WEDNESDAY AND THURSDAY
COULD RESULT IN PARTLY TO MOSTLY CLOUDY SKIES DUE TO THE PRESENCE OF
CUMULUS AND/OR STRATOCUMULUS.
HIGH TEMPERATURES WILL BE BELOW NORMAL TUESDAY AND WEDNESDAY WITH
HIGHS IN THE LOWER TO MID 60S...BUT MODERATE CLOSER TO NORMAL WITH
HIGHS IN THE UPPER 60S TO NEAR 70 BY THURSDAY. LOW TEMPERATURES ON
WEDNESDAY MORNING SHOULD BE IN THE UPPER 30S TO LOWER 40S INLAND
FROM THE IMMEDIATE COAST...BUT COULD GET COOLER INLAND IF WINDS FULLY
DECOUPLE. INCREASED CLOUD COVER THURSDAY MORNING WILL RESULT IN
LOWS IN THE LOWER TO MID 40S AWAY FROM THE IMMEDIATE COAST.
LAKE WINDS...WINDS SHOULD GUSTS TO 25 KT LATE TONIGHT AND
CONTINUE INTO TUESDAY AFTERNOON ON LAKE MOULTRIE AS MUCH COLDER
AND DRIER AIR MOVES IN OVER THE RELATIVELY WARM LAKE CREATING
IDEAL CONDITIONS FOR MIXING STRONG LOW-LEVEL WINDS DOWN TO THE
SURFACE. THUS...A LAKE WIND ADVISORY HAS BEEN ISSUED.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
MEDIUM RANGE IS IN FAIRLY GOOD AGREEMENT THROUGH THE LONG TERM
PERIOD. IN THE MID AND UPPER LEVELS OF THE ATMOSPHERE...A RIDGE WILL
BUILD ACROSS THE SOUTHEAST STATES FROM THE GULF OF MEXICO...BEFORE A
DEEP TROUGH SWINGS ACROSS THE CENTRAL U.S. ON SATURDAY THEN THE
EASTERN U.S. ON SUNDAY WITH A ZONAL FLOW RETURNING FOR MONDAY. AT
THE SURFACE...HIGH PRESSURE WILL MOVE OFF THE EASTERN SEABOARD ON
FRIDAY...ALLOWING A RETURN FLOW TO DEVELOP IN ADVANCE OF AN
APPROACHING COLD FRONT. THE FRONT SHOULD MOVE THROUGH LATE
SATURDAY AND SATURDAY NIGHT...FOLLOWED BY STRONG HIGH PRESSURE
BUILDING FROM THE NORTHWEST.
THERE IS A SLIGHT CHANCE OR CHANCE OF SHOWERS IN THE FORECAST
SATURDAY...SATURDAY NIGHT AND EARLY SUNDAY IN ASSOCIATION WITH THE
COLD FRONT...OTHERWISE RAIN-FREE CONDITIONS ARE EXPECTED. STRONG
WARM AIR ADVECTION AND COMPRESSIONAL HEATING AHEAD OF THE FRONT WILL
RESULT IN ABOVE NORMAL TEMPERATURES FRIDAY AND SATURDAY...WITH A
SIGNIFICANT COOL-DOWN EXPECTED BEHIND THE FRONT SUNDAY AND MONDAY.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
ABUNDANT LOW LEVEL MOISTURE HAS PRODUCED WIDESPREAD STRATUS ACROSS
THE AREA THIS MORNING...WITH IFR OR LOW-END MVFR CEILINGS EXPECTED TO
REMAIN IN PLACE AT THE TERMINALS THROUGH ABOUT 16Z...BEFORE
LIFTING MORE SOLIDLY INTO THE MVFR CATEGORY THROUGH ABOUT 22Z.
VFR CONDITIONS ARE THEN EXPECTED IN WAKE OF A PASSING COLD FRONT
AS WINDS VEER NORTHWEST AND EVENTUALLY NORTH AND CEILINGS
DISSIPATE. THERE COULD BE SOME SCATTERED SHOWERS AHEAD OF THE
FRONT FROM ABOUT MIDDAY THROUGH MID-LATE AFTERNOON AND HAVE
INDICATED MAINLY VCSH AT BOTH TERMINALS...WITH A FEW HOURS OF SHRA
FROM 19-22Z AT KSAV WHERE PROBABILITIES OF RAINFALL ARE SLIGHTLY
GREATER. THERE IS A LOW PROBABILITY FOR SOME THUNDERSTORMS AS
WELL...ESPECIALLY AT KSAV...BUT DUE TO UNCERTAINTY IN
TIMING/COVERAGE HAVE LEFT MENTION OUT OF THE FORECAST.
WINDS LATE TONIGHT INCREASE UPWARDS OF 30-35 KT WITHIN 2K FT OF
THE SURFACE...SO LOW LEVEL WIND SHEAR COULD BECOME A CONCERN. WILL
NEED TO MONITOR TRENDS FOR POSSIBLE INCLUSION IN LATER TAF
ISSUANCES.
EXTENDED AVIATION OUTLOOK...BREEZY CONDITIONS WILL BE POSSIBLE AT
BOTH TERMINALS THROUGH MIDWEEK...OTHERWISE VFR CONDITIONS WILL
PREVAIL.
&&
.MARINE...
TODAY...COASTAL WEBCAM AND PILOT BOAT REPORTS INDICATE VISIBILITIES
HAVE IMPROVED FOR ALL WATERS EXCEPT THE CHARLESTON COUNTY WATERS.
HAVE THEREFORE CANCELLED THE MARINE DENSE FOG ADVISORY FOR ALL BUT
AMZ350 AND THE CHARLESTON HARBOR WHERE DENSE FOG LINGERS NEAR THE
HARBOR ENTRANCE. THE SEA FOG IS EXPECTED TO GRADUALLY SHRINK BELOW
ADVISORY THRESHOLDS OFF THE CHARLESTON COUNTY COAST THIS
AFTERNOON...SO THE ADVISORY WILL REMAIN IN FORCE THROUGH NOON.
HOWEVER...SEA FOG IS RESILIENT AND HARD TO PREDICT. FURTHER
ADJUSTMENTS WILL BE NEEDED LATER TODAY. OTHERWISE...WINDS WILL
REMAIN FAIRLY BENIGN OVER THE WATERS TODAY WITH SEAS 2-4 FT.
TONIGHT...WEST WINDS WILL SHIFT TO THE NORTH AND INCREASE RAPIDLY
AS STRONG HIGH PRESSURE BUILDS INTO THE AREA BEHIND THE COLD
FRONT. EXPECT SOLID ADVISORY CONDITIONS TO DEVELOP FROM NORTH TO
SOUTH WITH GUSTS POSSIBLY NEARING GALE FORCE LATE BEYOND 20 NM.
SEAS WILL BUILD QUICKLY AS WELL...UP TO 6 FT WITHIN 20 NM AND UP
TO 8 FT IN THE 20-60 NM GA ZONE.
TUESDAY THROUGH SATURDAY...STRONG HIGH PRESSURE BUILDING FROM THE
NORTH WILL RESULT IN A TIGHT SURFACE PRESSURE GRADIENT THROUGH THE
MIDDLE OF THE WEEK...WITH A STRONG NORTHEAST FLOW EXPECTED AS COLD
AIR ADVECTION OCCURS OVER THE WATERS. WILL NEED TO MONITOR THIS
SITUATION AS MARGINAL GALE CONDITIONS ARE POSSIBLE OVER THE OUTER
GEORGIA WATERS INTO TUESDAY. FOR NOW...SMALL CRAFT ADVISORIES ARE IN
EFFECT FOR HAZARDOUS MARINE CONDITIONS THROUGH TUESDAY FOR THE
CHARLESTON HARBOR...THROUGH WEDNESDAY NIGHT FOR ALL NEAR SHORE
WATERS...AND INTO THURSDAY NIGHT FOR THE OUTER GEORGIA WATERS WHERE
SEAS WILL REMAIN ELEVATED DESPITE DIMINISHING WINDS ON
THURSDAY/THURSDAY NIGHT. WINDS WILL BEGIN TO VEER ON FRIDAY WITH A
SOUTHERLY RETURN FLOW DEVELOPING BY SATURDAY AHEAD OF AN APPROACHING
COLD FRONT. WINDS AND SEAS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY
LEVELS FRIDAY AND SATURDAY.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...LAKE WIND ADVISORY FROM 1 AM TO 4 PM EST TUESDAY FOR SCZ045.
MARINE...SMALL CRAFT ADVISORY FROM 1 AM TUESDAY TO 6 AM EST THURSDAY
FOR AMZ352-354.
DENSE FOG ADVISORY UNTIL NOON EST TODAY FOR AMZ330-350.
SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 6 AM EST
THURSDAY FOR AMZ350.
SMALL CRAFT ADVISORY FROM 1 AM TUESDAY TO MIDNIGHT EST
THURSDAY NIGHT FOR AMZ374.
SMALL CRAFT ADVISORY FROM 1 AM TO 4 PM EST TUESDAY FOR AMZ330.
&&
$$
ST
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
639 AM EST MON NOV 18 2013
.PREV DISCUSSION... /ISSUED 413 AM EST MON NOV 18 2013/
SHORT TERM /TODAY THROUGH TONIGHT/...
AT THE SURFACE...COLD FRONT MOVING THROUGH WILL BRING SHOWERS ALONG
AND AHEAD OF IT THROUGH EARLY TO MIDDAY MONDAY ENDING FROM NORTH TO
SOUTH AS IT MOVES THROUGH. ALOFT...MAIN UPPER LEVEL ENERGY
RESPONSIBLE FOR THE SEVERE OUTBREAK ON SUNDAY ACROSS THE OHIO VALLEY
REGION IS MOVING THROUGH THE GREAT LAKES AND AWAY FROM OUR REGION.
END RESULT IS GENERALLY ZONAL FLOW IN THE MID AND UPPER LEVELS
ACROSS THE SOUTHEAST U.S. WITH SURFACE HIGH PRESSURE BUILDING IN
BEHIND THE FRONT. HAVE KEPT HIGH POPS IN WITH THE FRONT AS IT
PROGRESSES SOUTH AND EAST BUT TAPER THEM OFF QUICKLY BEHIND. HAVE
ALSO REMOVED ALL MENTION OF THUNDER AS INSTABILITY IS ALL BUT GONE.
MAIN CONCERN WITH THE FRONT IS GUSTY WINDS WITH THE SHOWERS MIXING
SOME OF THE STRONG WINDS OFF THE SURFACE DOWN. VAD WINDS SHOWING 20
TO 30 KTS IN THE LOWEST FEW THOUSAND FEET. HAVE ALREADY SEEN SOME
GUSTS TO NEAR 40 MPH ACROSS NORTH GA WITH SOME OF THE SHOWERS.
WINDS WILL PICK UP THROUGH THE DAY AS THE CLEARING LINE PROGRESSES
THROUGH THE REGION AND THE SURFACE RIDGE BUILDS IN.
OTHERWISE...THE REMAINDER OF THE SHORT TERM FORECAST LOOKS GOOD.
USED A MODEL BLEND FOR MOST ELEMENTS...WITH THE RUC AND HRRR IN THE
IMMEDIATE SHORT TERM.
30
LONG TERM /TUESDAY THROUGH SUNDAY/...
QUIET WEATHER IS ON TAP FOR MOST OF THE LONG TERM PERIOD. A COLD
FRONT IS EXPECTED TO IMPACT THE CWFA LATE IN THE WEEK/EARLY PART OF
THE WEEKEND...BRINGING THE NEXT BEST CHANCES FOR PRECIPITATION.
HIGH PRESSURE WILL CONTINUE ACROSS THE SE US THROUGH WEDNESDAY
BEFORE BEGINNING TO SHIFT EASTWARD ON THURSDAY. A COLD FRONT WILL
MOVE INTO THE MISSISSIPPI RIVER VALLEY ON FRIDAY. THE FRONT IS
EXPECTED TO MOVE THROUGH THE CWFA ON SATURDAY...WITH HIGH PRESSURE
RETURNING FOR THE REMAINDER OF THE WEEKEND INTO THE EARLY PART OF
NEXT WEEK.
PRECIP CHANCES WILL BEGIN TO INCREASE LATER ON THURSDAY AS MOISTURE
BEGINS TO INCREASE AHEAD OF THE APPROACHING FRONTAL BOUNDARY. THE
FRONT IS STILL PROGGED TO COME THROUGH DURING THE DAY ON
SATURDAY...WITH THE MODELS INDICATING SOME MARGINAL INSTABILITY AT
THIS TIME. WILL KEEP THE MENTION OF THUNDER.
STRONG HIGH PRESSURE WILL BUILD BEHIND THE FRONTAL BOUNDARY...AND
BREEZY/WIND CONDITIONS ARE POSSIBLE SATURDAY NIGHT INTO SUNDAY. IN
ADDITION...A COLDER AND DRIER AIRMASS WILL SETTLE OVER THE SOUTHERN
STATES.
NLISTEMAA
&&
.AVIATION...
12Z UPDATE...
COLD FRONT EXTENDING FROM CSG TO MCN AT 12Z WILL CONTINUE MOVING
SOUTH THROUGH THE AREA. WIND SHIFT TO THE NW ASSOCIATED WITH THE
FRONT AS WELL AS AN END TO ANY IFR CIGS. WILL MAINTAIN SOME MVFR
CIGS FOR A COUPLE HOURS BEHIND THE FRONT BEFORE GOING VFR AREAWIDE
BY 18Z. WITH THE COLD AIR FILTERING IN...IS POSSIBLE FOR SOME CU
EARLY THIS AFTERNOON...BUT CONFIDENCE IS LOW. GUSTY NORTHWEST
WINDS IN STORE THIS AFTERNOON AT ALL TAF SITES BEFORE RELAXING A
BIT AFTER SUNSET.
//ATL CONFIDENCE...12Z UPDATE...
MEDIUM CONFIDENCE ON TIMING OF CIG HEIGHT CHANGES.
HIGH CONFIDENCE ALL OTHER ELEMENTS.
30
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 72 46 59 36 / 20 0 5 0
ATLANTA 71 47 59 38 / 30 0 0 5
BLAIRSVILLE 66 38 56 32 / 20 0 0 0
CARTERSVILLE 69 42 58 36 / 30 0 0 0
COLUMBUS 77 53 64 41 / 70 0 5 5
GAINESVILLE 68 45 57 36 / 20 5 0 0
MACON 78 50 62 38 / 60 5 5 5
ROME 68 43 58 36 / 20 0 0 5
PEACHTREE CITY 73 45 60 37 / 30 0 5 5
VIDALIA 80 55 63 41 / 50 10 5 5
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...30
LONG TERM....NLISTEMAA
AVIATION...30
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
529 AM CST MON NOV 18 2013
.DISCUSSION...
SEE THE 12Z AVIATION DISCUSSION BELOW.
40
&&
.AVIATION...
THE FOG WAS BEGINNING TO LIFT AT BOTH KCLL AND KUTS AT 11Z AND
EXPECT BOTH TO BE MVFR BY 12Z. HOWEVER...THE IS A CHANCE THAT IFR
FOG MAY LINGER PAST 12Z. OTHERWISE...THE COLD FRONT THAT IS MOVING
SOUTHWARD AND HELPING TO LIFT THE FOG SHOULD ARRIVE AT KCXO AND
KIAH BY 14Z...15Z AT KHOU...16Z AT KSGR...17Z AT KLBX...AND 18Z AT
KGLS. LESS SURE OF THE TIMING AFTER THE FRONT PUSHES THROUGH THE
BIG METRO AIRPORTS. THIS AFTERNOON SHOULD SEE VFR CONDITIONS
DEVELOPING.
40
&&
.PREV DISCUSSION... /ISSUED 423 AM CST MON NOV 18 2013/
MARINE...
DENSE SEA FOG WILL LIKELY PERSIST THROUGH MUCH OF THE MORNING...
GIVEN THE WATER TEMPERATURES IN THE MID 60S BEING OVERRUN BY AN
AIR MASS WITH DEWPOINTS IN THE LOWER 70S. THE GFS MODEL
STATISTICAL GUIDANCE FOR GALVESTON INDICATES THAT THE SEA FOG WILL
PERSIST THROUGH MID MORNING AND THEN BEGIN LIFTING AS THE COLD
FRONT PUSHES OFF THE COAST. EXPECT THAT GALVESTON BAY WILL SEE
IMPROVEMENTS FIRST DURING THE MID MORNING PERIOD...FOLLOWED BY THE
GULF WATERS EAST OF FREEPORT DURING THE MID TO LATE MORNING. THE
WATERS WEST OF FREEPORT AND MATAGORDA BAY MAY EXPERIENCE THE SEA
FOG THROUGH NOON TIME.
BEHIND THE FRONT MODERATE TO STRONG NORTHEAST WINDS ARE EXPECTED
TO DEVELOP TONIGHT AND THEN SLOWLY DIMINISH THROUGH TUESDAY
NIGHT. AFTER A PERIOD OF ONSHORE WINDS...A STRONGER FRONT IS
EXPECTED TO PUSH OFF THE COAST ON FRIDAY.
PREV DISCUSSION... /ISSUED 347 AM CST MON NOV 18 2013/
DISCUSSION...
DENSE FOG CONTINUES TO BLANKET MUCH OF SOUTHEAST TEXAS THIS
MORNING. A WEAK COLD FRONT IS DRAPED ACROSS THE EXTREME NORTHERN
PART OF THE CWA AND IS DRIFTING SLOWLY SOUTH. AM EXPECTING A
GRADUAL IMPROVEMENT IN VISIBILITY OVER THE NORTH AS DRIER AIR
FILTERS INTO THE REGION. CROCKETT HAS ALREADY CLEARED OUT BUT
HUNTSVILLE IS STILL BELOW A 1/2 MILE. THE FRONT WILL MOVE THROUGH
SE TX TODAY BUT THE SLOW MOVEMENT WILL ALLOW FOGGY CONDS TO
PREVAIL ALONG THE COAST THROUGH LATE MORNING. WILL ADJUST THE
DENSE FOG ADVISORY RIGHT BEFORE SENDING THE ZFP TO TRY AND MATCH
UP WITH CURRENT OBS. THE BOUNDARY COULD ALSO TRIGGER A FEW SHOWERS
AS IT ENCOUNTERS DEEP MOISTURE CLOSER TO THE COAST. SATELLITE
DERIVED PW VALUES ARE NEAR 2.0 INCHES ALONG THE COAST AND THE RAP
AND HRRR WANT TO DEVELOP PRECIP ALONG THE BOUNDARY LATER THIS
MORNING. WILL MAINTAIN CHC/SLT CHC POPS FOR AREAS GENERALLY EAST
OF I-69.
TUESDAY LOOKS QUIET BUT MOISTURE BEGINS TO RETURN ON WEDNESDAY.
PWATS INCREASE TO 1.6 INCHES ON WED AND NAM 12 FCST SOUNDINGS SHOW
A DEEP SATURATED LAYER BETWEEN 900-600 MB. THE GFS IS LESS
AGGRESSIVE BUT STILL SHOWS A SATURATED LAYER BETWEEN 950-700 MB.
WILL MAINTAIN SLT RAIN CHANCES FOR MAINLY THE SW HALF OF THE
REGION. A WARM FRONT WILL MOVE ACROSS SE TX WED NITE AND THURSDAY.
SOME LIGHT RAIN WILL ACCOMPANY THE FRONT AS IT MOVES NORTH. A
WEAK UPPER LEVEL DISTURBANCE COUPLED WITH DEEPER MOISTURE WILL
YIELD A CHANCE OF SHOWERS ON THURSDAY.
MODELS IN BETTER AGREEMENT WITH THE TIMING AND STRENGTH OF THE NEXT
COLD FRONT. THE ECMWF IS STILL FASTER THAN THE GFS. THE GFS IS
TRENDING A BIT FASTER AND THE ECMWF IS TRENDING A BIT SLOWER SO
THE TIMING OF THE FROPA SHOULD BE DURING THE DAY ON FRIDAY. PWATS
INCREASE TO 1.8 INCHES AHEAD OF THE FRONT. JET DYNAMICS ARE
LACKING A BIT BUT THE FRONT SHOULD SERVE AS A CATALYST FOR
SHRA/TSRA. WILL MAINTAIN HIGH END CHC POPS FOR NOW. CONSIDERABLY
COLDER TEMPERATURES WILL MOVE INTO SE TX FOR THE WEEKEND.
ISENTROPIC UPGLIDE SHOULD PERSIST INTO SATURDAY MORNING AS SW
WINDS ALOFT OVERRIDE N-NE SFC WINDS. PRECIP SHOULD END ON SAT AFTN
AS A STRONG UPPER LOW OVER BAJA RETROGRADES SLIGHTLY AND THIS WILL
ALLOW WEAK RIDGING TO AMPLIFY OVER DEEP SOUTH TEXAS. AS A
RESULT...UPPER LEVEL WINDS BRIEFLY BECOME WEST AND END THE
ISENTROPIC LIFT. IT WILL REMAIN UNSEASONABLY COLD THROUGH THROUGH
THE WEEKEND. THE UPPER LOW WILL BEGIN TO MOVE EAST ON MONDAY AND
SW WINDS ALOFT REDEVELOP. THE UPPER LOW WILL MOVE ACROSS THE STATE
NEXT TUES AND A COASTAL LOW WILL DEVELOP OFF CORPUS. THE TWO
FEATURES SHOULD BRING A GOOD CHANCE OF RAIN TO THE REGION NEXT
TUESDAY. 43
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 77 53 71 54 74 / 10 10 10 10 10
HOUSTON (IAH) 78 54 71 56 74 / 20 10 10 10 20
GALVESTON (GLS) 78 62 69 63 74 / 30 10 10 10 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...DENSE FOG ADVISORY UNTIL 9 AM CST THIS MORNING FOR THE FOLLOWING
ZONES: AUSTIN...BRAZORIA...BRAZOS...CHAMBERS...COLORADO...
FORT BEND...GALVESTON...GRIMES...HARRIS...JACKSON...
LIBERTY...MATAGORDA...MONTGOMERY...POLK...SAN JACINTO...
WALKER...WALLER...WASHINGTON...WHARTON.
GM...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR THE FOLLOWING ZONES:
GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...43
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
423 AM CST MON NOV 18 2013
.MARINE...
DENSE SEA FOG WILL LIKELY PERSIST THROUGH MUCH OF THE MORNING...
GIVEN THE WATER TEMPERATURES IN THE MID 60S BEING OVERRUN BY AN
AIR MASS WITH DEWPOINTS IN THE LOWER 70S. THE GFS MODEL
STATISTICAL GUIDANCE FOR GALVESTON INDICATES THAT THE SEA FOG WILL
PERSIST THROUGH MID MORNING AND THEN BEGIN LIFTING AS THE COLD
FRONT PUSHES OFF THE COAST. EXPECT THAT GALVESTON BAY WILL SEE
IMPROVEMENTS FIRST DURING THE MID MORNING PERIOD...FOLLOWED BY THE
GULF WATERS EAST OF FREEPORT DURING THE MID TO LATE MORNING. THE
WATERS WEST OF FREEPORT AND MATAGORDA BAY MAY EXPERIENCE THE SEA
FOG THROUGH NOON TIME.
BEHIND THE FRONT MODERATE TO STRONG NORTHEAST WINDS ARE EXPECTED
TO DEVELOP TONIGHT AND THEN SLOWLY DIMINISH THROUGH TUESDAY
NIGHT. AFTER A PERIOD OF ONSHORE WINDS...A STRONGER FRONT IS
EXPECTED TO PUSH OFF THE COAST ON FRIDAY.
&&
.PREV DISCUSSION... /ISSUED 347 AM CST MON NOV 18 2013/
DISCUSSION...
DENSE FOG CONTINUES TO BLANKET MUCH OF SOUTHEAST TEXAS THIS
MORNING. A WEAK COLD FRONT IS DRAPED ACROSS THE EXTREME NORTHERN
PART OF THE CWA AND IS DRIFTING SLOWLY SOUTH. AM EXPECTING A
GRADUAL IMPROVEMENT IN VISIBILITY OVER THE NORTH AS DRIER AIR
FILTERS INTO THE REGION. CROCKETT HAS ALREADY CLEARED OUT BUT
HUNTSVILLE IS STILL BELOW A 1/2 MILE. THE FRONT WILL MOVE THROUGH
SE TX TODAY BUT THE SLOW MOVEMENT WILL ALLOW FOGGY CONDS TO
PREVAIL ALONG THE COAST THROUGH LATE MORNING. WILL ADJUST THE
DENSE FOG ADVISORY RIGHT BEFORE SENDING THE ZFP TO TRY AND MATCH
UP WITH CURRENT OBS. THE BOUNDARY COULD ALSO TRIGGER A FEW SHOWERS
AS IT ENCOUNTERS DEEP MOISTURE CLOSER TO THE COAST. SATELLITE
DERIVED PW VALUES ARE NEAR 2.0 INCHES ALONG THE COAST AND THE RAP
AND HRRR WANT TO DEVELOP PRECIP ALONG THE BOUNDARY LATER THIS
MORNING. WILL MAINTAIN CHC/SLT CHC POPS FOR AREAS GENERALLY EAST
OF I-69.
TUESDAY LOOKS QUIET BUT MOISTURE BEGINS TO RETURN ON WEDNESDAY.
PWATS INCREASE TO 1.6 INCHES ON WED AND NAM 12 FCST SOUNDINGS SHOW
A DEEP SATURATED LAYER BETWEEN 900-600 MB. THE GFS IS LESS
AGGRESSIVE BUT STILL SHOWS A SATURATED LAYER BETWEEN 950-700 MB.
WILL MAINTAIN SLT RAIN CHANCES FOR MAINLY THE SW HALF OF THE
REGION. A WARM FRONT WILL MOVE ACROSS SE TX WED NITE AND THURSDAY.
SOME LIGHT RAIN WILL ACCOMPANY THE FRONT AS IT MOVES NORTH. A
WEAK UPPER LEVEL DISTURBANCE COUPLED WITH DEEPER MOISTURE WILL
YIELD A CHANCE OF SHOWERS ON THURSDAY.
MODELS IN BETTER AGREEMENT WITH THE TIMING AND STRENGTH OF THE NEXT
COLD FRONT. THE ECMWF IS STILL FASTER THAN THE GFS. THE GFS IS
TRENDING A BIT FASTER AND THE ECMWF IS TRENDING A BIT SLOWER SO
THE TIMING OF THE FROPA SHOULD BE DURING THE DAY ON FRIDAY. PWATS
INCREASE TO 1.8 INCHES AHEAD OF THE FRONT. JET DYNAMICS ARE
LACKING A BIT BUT THE FRONT SHOULD SERVE AS A CATALYST FOR
SHRA/TSRA. WILL MAINTAIN HIGH END CHC POPS FOR NOW. CONSIDERABLY
COLDER TEMPERATURES WILL MOVE INTO SE TX FOR THE WEEKEND.
ISENTROPIC UPGLIDE SHOULD PERSIST INTO SATURDAY MORNING AS SW
WINDS ALOFT OVERRIDE N-NE SFC WINDS. PRECIP SHOULD END ON SAT AFTN
AS A STRONG UPPER LOW OVER BAJA RETROGRADES SLIGHTLY AND THIS WILL
ALLOW WEAK RIDGING TO AMPLIFY OVER DEEP SOUTH TEXAS. AS A
RESULT...UPPER LEVEL WINDS BRIEFLY BECOME WEST AND END THE
ISENTROPIC LIFT. IT WILL REMAIN UNSEASONABLY COLD THROUGH THROUGH
THE WEEKEND. THE UPPER LOW WILL BEGIN TO MOVE EAST ON MONDAY AND
SW WINDS ALOFT REDEVELOP. THE UPPER LOW WILL MOVE ACROSS THE STATE
NEXT TUES AND A COASTAL LOW WILL DEVELOP OFF CORPUS. THE TWO
FEATURES SHOULD BRING A GOOD CHANCE OF RAIN TO THE REGION NEXT
TUESDAY. 43
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 77 53 71 54 74 / 10 10 10 10 10
HOUSTON (IAH) 78 54 71 56 74 / 20 10 10 10 20
GALVESTON (GLS) 78 62 69 63 74 / 30 10 10 10 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...DENSE FOG ADVISORY UNTIL 9 AM CST THIS MORNING FOR THE FOLLOWING
ZONES: AUSTIN...BRAZORIA...BRAZOS...CHAMBERS...COLORADO...
FORT BEND...GALVESTON...GRIMES...HARRIS...JACKSON...
LIBERTY...MATAGORDA...MONTGOMERY...POLK...SAN JACINTO...
WALKER...WALLER...WASHINGTON...WHARTON.
GM...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR THE FOLLOWING ZONES:
GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...43
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS ALBANY NY
536 PM EST MON NOV 18 2013
.SYNOPSIS...
AS COLDER AIR WORKS INTO THE REGION TONIGHT...LAKE ENHANCED RAIN AND
SNOW SHOWERS WILL AFFECT WESTERN AND NORTHERN PARTS OF THE AREA.
TEMPERATURES TOMORROW WILL BE MUCH COLDER THAN RECENT DAYS...WITH A
GUSTY WESTERLY WIND. HIGH PRESSURE PASSING OVER THE AREA WILL ALLOW
FOR DRY WEATHER FOR THE REMAINDER OF THE WORK WEEK...WITH
TEMPERATURES SLOWLY MODERATING BACK TO NORMAL LEVELS.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 530 PM EST...COLD FRONT JUST SLIPPED SOUTH OF I90 PER THE DUAL
POL RADAR DATA. SOME SHOWERS HAVE DEVELOPED ON THE UPSLOPE AREAS OF
THE SCHOHARIE VALLEY AND HELDERBERGS AND WITH THE MEAN WESTERLY
FLOW...THESE ISOLATED SHOWERS HAVE MOVED INTO THE CAPITAL REGION.
FURTHERMORE...TERRAIN ENHANCEMENT ACROSS THE SOUTHERN GREENS HAVE
TOO INITIATED SOME SHOWERS. SO WE WILL INCREASE POPS/WX THROUGH THE
EVENING HOURS AND WATCH LAKE EFFECT ACTIVITY PICK UP DOWNWIND OF
LAKE ONTARIO. PER THE RUC13 LOW LEVEL CONVERGENCE FIELDS...SEEMS
BAND/S/ OF PRECIP SHOULD INCREASE ACROSS CENTRAL HERKIMER COUNTY
WITH A TENDENCY TO SLIDE SOUTHWARD AND WEAKEN OVERNIGHT. THE
CURRENT FORECAST ACROSS THAT PART OF THE CWA REMAINS IN EXCELLENT
SHAPE. OTHERWISE...PER HOURLY TEMPS...DID SLOW DOWN THE NOCTURNAL
CURVE A BIT AND CLOSER TO THE LAMP/LAV AND 2KM HRRR/RUC13.
AS OF 400 PM EST...A STRONG AND VERTICALLY STACKED STORM SYSTEM
OVER WESTERN QUEBEC WILL FILL IN AND WEAKEN OVERNIGHT. WITH THE
TROUGH AXIS CENTERED OVER THE NORTHEASTERN US...THE CYCLONIC FLOW
AROUND THE UPPER LOW WILL PASS OVER THE NORTHERN AND EASTERN GREAT
LAKES. INITIALLY...THE LOW TO MID LEVEL FLOW WILL BE IN A W-SW
DIRECTION...WHICH WILL ALLOW FOR SOME LAKE ENHANCED RAIN AND SNOW
SHOWERS THIS EVENING OVER THE NORTHWESTERN ADIRONDACKS...AS STRONG
CAA DROP 850 HPA TEMPS FROM AROUND 0 TO +4 DEGREES C THIS
AFTN...TO -8 TO -12 DEGREES C BY LATE TONIGHT.
AS BOUNDARY LAYER TEMPS ALSO COOL DOWN...PTYPE WILL CHANGE TO SNOW
ACROSS THE REGION. THE MEAN WIND SHIFTS TO THE WEST DURING THE
OVERNIGHT HOURS AND EVENTUALLY NORTHWEST BY LATE TONIGHT. OUR LOCAL
WFOWRF...AS WELL AS THE LATEST 3KM HRRR...ALL SUGGEST THAT SOME OF
THIS LAKE ENHANCED ACTIVITY WILL PASS ACROSS WESTERN AND NORTHERN
PARTS OF OUR AREA DURING THE OVERNIGHT HOURS. DUE TO THE EXPECTED
AMOUNTS OF SHEAR AND WIND DIRECTION...THE ACTIVITY WILL GENERALLY BE
MULTI-BAND IN NATURE...AND THE INVERSION HEIGHT OF ONLY 2.5-3 KM
WILL PREVENT ANY MEANINGFUL SNOW BANDS FROM OCCURRING.
WHILE THE BULK OF THE ACTIVITY WILL EITHER BY ACROSS THE HIGH
TERRAIN OR THE WESTERN MOHAWK VALLEY...IT/S POSSIBLE THAT A
FLURRY OR SPRINKLE MAY MAKE IT INTO THE HUDSON VALLEY REGION AND
CAPITAL REGION BY LATE TONIGHT. NO SNOW ACCUMULATION IS EXPECTED FOR
THE CAPITAL REGION/HUDSON VALLEY AREAS. ELSEWHERE..SNOW ACCUM WILL
RANGE FROM JUST A DUSTING TO UP TO TWO INCHES ACROSS THE WESTERN
ADIRONDACKS.
TEMPS WILL BE MUCH COLDER FOR TONIGHT THAN RECENT NIGHTS...WITH MINS
RANGING FROM THE MID 20S TO MID 30S. IN ADDITION...THE W-NW SFC
WIND WILL CONTINUE TO BE GUSTY OVERNIGHT...WITH SUSTAINED WINDS OF
10 TO 20 MPH WITH A FEW HIGHER GUSTS...ESP FOR THE MOHAWK VALLEY AND
CAPITAL REGION.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
WITH SFC HIGH PRESSURE BUILDING INTO THE REGION ON TUESDAY AND THE
FLOW ALOFT BECOMING ANTICYCLONIC AND INVERSION HEIGHTS
LOWERING...LAKE EFFECT ACTIVITY WILL END. A FEW SNOW SHOWERS ARE
POSSIBLE EARLY IN THE DAY ACROSS SCHOHARIE COUNTY AND THE EASTERN
CATSKILLS...OTHERWISE IT WILL BE DRY UNDER A PARTLY TO MOSTLY
SUNNY SKY WITH A CONTINUED GUSTY NW BREEZE. TEMPS WILL BE MUCH
COLDER THAN RECENT DAYS...WITH MAX TEMPS IN THE 30S TO MID 40S
ACROSS THE REGION.
AS THE HIGH PRESSURE AREA BUILDS INTO THE REGION FOR TUESDAY
NIGHT...THE WIND WILL DIE OFF AND THIS SHOULD ALLOW FOR GOOD
RADIATIONAL COOLING. TEMPS WILL BE VERY COLD TOMORROW NIGHT...WITH
TEMPS RANGING FROM THE SINGLE DIGITS OVER THE CENTRAL ADIRONDACKS TO
THE TEENS AND LOW 20S ELSEWHERE.
THE HIGH PRESSURE AREA WILL REMAIN SITUATED OVER THE NORTHEAST FOR
WEDNESDAY THROUGH THURSDAY AS WELL...KEEPING THE DRY WEATHER IN
PLACE. MAX TEMPS ON WED WILL BE COLD ONCE AGAIN...WITH 30S AND LOW
40S. HOWEVER...WITH A LIGHT SOUTHERLY WIND DEVELOPING FOR WED NIGHT
AND A FEW MORE CLOUDS ACROSS THE AREA...MIN TEMPS WON/T BE AS COLD
FOR WED NIGHT...WITH 20S OVER THE MAJORITY OF THE AREA. TEMPS WILL
START TO MODERATE ON THURSDAY AS OUR REGION WILL BE IN A RETURN
FLOW AROUND THE SLOWLY DEPARTING HIGH...WITH 40S ACROSS THE ENTIRE
REGION...AND A FEW MORE CLOUDS AROUND...ESP FOR WESTERN PARTS OF
THE AREA.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE PERIOD BEGINS WITH THE PASSAGE OF A COLD FRONT THAT WILL BRING
VERY LITTLE MOISTURE AND THUS LITTLE IN THE WAY OF PRECIPITATION.
BUT LOW PRESSURE STRENGTHENING ALONG THE FRONT OVER THE OHIO VALLEY
ON FRIDAY WILL RAPIDLY BUILD MOISTURE INTO THE REGION. THE LOW WILL
TRACK ALONG THE MID-ATLANTIC REGION AND UP THE NEW ENGLAND COAST
FRIDAY NIGHT AND SATURDAY...A TRAJECTORY WHICH COULD RESULT IN OUR
FIRST SIGNIFICANT WINTER WEATHER EVENT...CONSISTING OF A MIXED BAG
OF PRECIPITATION TYPES.
A WEST TO NORTHWESTERLY FLOW BEHIND THE SYSTEM ON SUNDAY WILL DRAW
IN SIGNIFICANTLY COLDER AIR AND TURN ON THE LAKE EFFECT MACHINE...
WITH A GOOD CHANCE FOR SNOW SHOWERS FROM SATURDAY AFTERNOON THROUGH
SUNDAY. THIS COULD BE WET SNOW FOR THE MID HUDSON VALLEY. WITH THE
FLOW WEAKENING SUNDAY NIGHT...LAKE EFFECT SHOULD BECOME LIMITED TO
THE WESTERN ADIRONDACKS...ALTHOUGH MOST REMAINING LOCATIONS WILL
STILL HAVE A SLIGHT CHANCE OF SEEING SOMETHING. BY MONDAY...THINGS
SHOULD BE QUIETED DOWN AS HIGH PRESSURE RIDGES IN FROM THE SOUTHERN
APPALACHIANS. THERE WILL BE A GOOD MIX OF SUN AND CLOUDS MONDAY...B
UT LITTLE BOUNCE BACK IN TEMPERATURES.
LOWS THURSDAY AND FRIDAY NIGHTS WILL RANGE FROM THE MID OR UPPER 20S
TO THE MID 30S. BEHIND THE WEEKEND STORM SYSTEM...LOWS WILL BE IN
THE UPPER TEENS AND THE 20S SATURDAY NIGHT. THEY WILL RANGE FROM
ONLY AROUND 10 DEGREES IN THE ADIRONDACKS...TO AROUND 20 DEGREES IN
THE MID HUDSON VALLEY SUNDAY NIGHT. HIGH TEMPERATURES WILL RANGE
FROM THE MID 30S IN THE WESTERN ADIRONDACKS...TO AROUND 50 DEGREES
IN THE MID HUDSON VALLEY ON FRIDAY...COOLING TO FROM AROUND 30 TO
THE MID 40S ON SATURDAY...THE LOWER 20S TO MID 30S ON SUNDAY...WITH
A COUPLE OF DEGREES OF BOUNCE BACK IN THE NORTHWESTERN HALF OF THE
FORECAST AREA FOR MONDAY. NORMAL TEMPERATURES FOR ALBANY DURING
THIS PERIOD ARE MID 40S FOR HIGHS AND AROUND 30 FOR LOWS.
&&
.AVIATION /21Z MONDAY THROUGH SATURDAY/...
VFR CONDITIONS AND BREEZY CONDITIONS WILL PREVAIL THROUGHOUT THE TAF
PERIOD.
THIS AFTERNOON...GENERALLY CLEARING SKIES ARE EXPECTED AT ALL TAF
SITES EXCEPT FOR KGFL...WHERE PERIODIC BROKEN STRATOCUMULUS AROUND 5
KFT WILL REMAIN AS BROAD CYCLONIC FLOW LINGERS ALOFT BEHIND THE EXIT
OF A POWERFUL STORM SYSTEM. WESTERLY WINDS WILL CONTINUE TO BE
BREEZY THIS AFTERNOON AND THROUGH TONIGHT...GENERALLY BETWEEN 10-15
KNOTS WITH OCCASIONAL GUSTS UP TO 25 KNOTS LIKELY.
TONIGHT INTO TUESDAY...A SECONDARY WEAK COLD FRONT WILL SKIRT ACROSS
THE REGION TONIGHT...WITH RELATIVELY LITTLE IMPACT EXCEPT FOR SOME
PASSING CLOUDS. HIGH PRESSURE WILL BEGIN TO BUILD ACROSS THE REGION
FROM THE SOUTH ON TUESDAY WITH CLEARING SKIES...BUT CONTINUED BREEZY
CONDITIONS AS A TIGHT PRESSURE GRADIENT KEEPS NORTHWESTERLY WINDS
BETWEEN 10-20 KNOTS.
OUTLOOK...
TUESDAY NIGHT-THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN...RA.
FRIDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF RA...SN.
SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF
SHRA...RA...SN...SLEET.
&&
.HYDROLOGY...
NO HYDRO ISSUES ARE EXPECTED OVER THE NEXT FIVE DAYS.
LAKE EFFECT RAIN AND SNOW SHOWERS WILL AFFECT THE ADIRONDACKS AND
MOHAWK VALLEY TONIGHT...WITH UP TO A QUARTER OF AN INCH OF LIQUID
EQUIVALENT PRECIPITATION EXPECTED. THIS PRECIP WILL HAVE LITTLE TO
NO EFFECT ON AREA WATERWAYS. ANY LAKE EFFECT ACTIVITY WILL END ON
TUESDAY MORNING...AS HIGH PRESSURE BUILDS INTO THE AREA.
HIGH PRESSURE WILL BE IN CONTROL OF THE WEATHER OVER THE REGION
THROUGH THURSDAY...ALLOWING FOR DRY WEATHER. THIS WILL ALLOW RIVERS
AND STREAMS TO HOLD STEADY OR RECEDE...WITH FLOWS EXPECTED TO BE
AROUND SEASONAL LEVELS. A STORM SYSTEM LOOKS TO MOVE ACROSS THE
REGION SOMETIME BETWEEN FRIDAY AND NEXT WEEKEND...WITH RAIN AND SNOW
POSSIBLE.
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...FRUGIS
NEAR TERM...FRUGIS/BGM
SHORT TERM...FRUGIS
LONG TERM...ELH
AVIATION...IRL
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
1225 PM EST MON NOV 18 2013
.UPDATE...
/ISSUED AT 948 AM EST MON NOV 18 2013/
FRONT CONTINUING TO MOVE RAPIDLY THROUGH THE CWA. IT HAS NOW CLEARED
MCN AND CSG. SCATTERED SHOWERS THAT HAD OCCURRED ALONG THE FRONT
HAVE DISSIPATED. THERE COULD BE A FEW SHOWERS DEVELOP AHEAD OF THE
FRONT BEFORE IT PUSHES OUT OF THE CWA AROUND NOON AND HAVE LEFT LOW
CHANCE POPS FOR THE EXTREME SOUTHEAST CORNER OF THE CWA UNTIL NOON.
HAVE TAKEN POPS OUT OF THE FORECAST FOR THIS AFTERNOON AND EVENING
AS DRIER AND MORE STABLE AIR SPREADS ACROSS THE CWA. FORECAST TEMPS
LOOK ON TRACK AS WE ARE GETTING A GOOD REBOUND ACROSS NORTH GA.
LATEST PROGS SHOW THE CAA MOVING INTO THE STATE TONIGHT.
&&
.SHORT TERM /TODAY THROUGH TONIGHT/...
/ISSUED 413 AM EST MON NOV 18 2013/
AT THE SURFACE...COLD FRONT MOVING THROUGH WILL BRING SHOWERS ALONG
AND AHEAD OF IT THROUGH EARLY TO MIDDAY MONDAY ENDING FROM NORTH TO
SOUTH AS IT MOVES THROUGH. ALOFT...MAIN UPPER LEVEL ENERGY
RESPONSIBLE FOR THE SEVERE OUTBREAK ON SUNDAY ACROSS THE OHIO VALLEY
REGION IS MOVING THROUGH THE GREAT LAKES AND AWAY FROM OUR REGION.
END RESULT IS GENERALLY ZONAL FLOW IN THE MID AND UPPER LEVELS
ACROSS THE SOUTHEAST U.S. WITH SURFACE HIGH PRESSURE BUILDING IN
BEHIND THE FRONT. HAVE KEPT HIGH POPS IN WITH THE FRONT AS IT
PROGRESSES SOUTH AND EAST BUT TAPER THEM OFF QUICKLY BEHIND. HAVE
ALSO REMOVED ALL MENTION OF THUNDER AS INSTABILITY IS ALL BUT GONE.
MAIN CONCERN WITH THE FRONT IS GUSTY WINDS WITH THE SHOWERS MIXING
SOME OF THE STRONG WINDS OFF THE SURFACE DOWN. VAD WINDS SHOWING 20
TO 30 KTS IN THE LOWEST FEW THOUSAND FEET. HAVE ALREADY SEEN SOME
GUSTS TO NEAR 40 MPH ACROSS NORTH GA WITH SOME OF THE SHOWERS.
WINDS WILL PICK UP THROUGH THE DAY AS THE CLEARING LINE PROGRESSES
THROUGH THE REGION AND THE SURFACE RIDGE BUILDS IN.
OTHERWISE...THE REMAINDER OF THE SHORT TERM FORECAST LOOKS GOOD.
USED A MODEL BLEND FOR MOST ELEMENTS...WITH THE RUC AND HRRR IN THE
IMMEDIATE SHORT TERM.
30
.LONG TERM /TUESDAY THROUGH SUNDAY/...
/ISSUED 413 AM EST MON NOV 18 2013/
QUIET WEATHER IS ON TAP FOR MOST OF THE LONG TERM PERIOD. A COLD
FRONT IS EXPECTED TO IMPACT THE CWFA LATE IN THE WEEK/EARLY PART OF
THE WEEKEND...BRINGING THE NEXT BEST CHANCES FOR PRECIPITATION.
HIGH PRESSURE WILL CONTINUE ACROSS THE SE US THROUGH WEDNESDAY
BEFORE BEGINNING TO SHIFT EASTWARD ON THURSDAY. A COLD FRONT WILL
MOVE INTO THE MISSISSIPPI RIVER VALLEY ON FRIDAY. THE FRONT IS
EXPECTED TO MOVE THROUGH THE CWFA ON SATURDAY...WITH HIGH PRESSURE
RETURNING FOR THE REMAINDER OF THE WEEKEND INTO THE EARLY PART OF
NEXT WEEK.
PRECIP CHANCES WILL BEGIN TO INCREASE LATER ON THURSDAY AS MOISTURE
BEGINS TO INCREASE AHEAD OF THE APPROACHING FRONTAL BOUNDARY. THE
FRONT IS STILL PROGGED TO COME THROUGH DURING THE DAY ON
SATURDAY...WITH THE MODELS INDICATING SOME MARGINAL INSTABILITY AT
THIS TIME. WILL KEEP THE MENTION OF THUNDER.
STRONG HIGH PRESSURE WILL BUILD BEHIND THE FRONTAL BOUNDARY...AND
BREEZY/WIND CONDITIONS ARE POSSIBLE SATURDAY NIGHT INTO SUNDAY. IN
ADDITION...A COLDER AND DRIER AIRMASS WILL SETTLE OVER THE SOUTHERN
STATES.
NLISTEMAA
&&
.AVIATION...
18Z UPDATE...
VFR CONDITIONS EXPECTED THROUGH THE FORECAST. SKIES WILL BE CLEAR
THROUGH EARLY TONIGHT...THEN CIRRUS WILL BEGIN SPREADING OVER THE
FORECAST AREA LATE TONIGHT AND CONTINUE INTO TUESDAY. WINDS WILL BE
NORTHWEST WITH GUSTS OF 15 TO 20KTS...DIMINISHING SOMEWHAT TONIGHT
AND THEN SWITCHING TO THE NORTHEAST/EAST ON TUESDAY.
//ATL CONFIDENCE...18Z UPDATE...
HIGH CONFIDENCE ON ALL ELEMENTS.
17
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 72 46 59 36 / 20 0 5 0
ATLANTA 71 47 59 38 / 30 0 0 5
BLAIRSVILLE 66 38 56 32 / 20 0 0 0
CARTERSVILLE 69 42 58 36 / 30 0 0 0
COLUMBUS 77 53 64 41 / 70 0 5 5
GAINESVILLE 68 45 57 36 / 20 5 0 0
MACON 78 50 62 38 / 60 5 5 5
ROME 68 43 58 36 / 20 0 0 5
PEACHTREE CITY 73 45 60 37 / 30 0 5 5
VIDALIA 80 55 63 41 / 50 10 5 5
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...30
LONG TERM....NLISTEMAA
AVIATION...30
AREA FORECAST DISCUSSION
NWS BOISE ID
237 PM MST MON NOV 18 2013
.SHORT TERM...TONIGHT THROUGH WEDNESDAY...A VIGOROUS AND FAST-
MOVING SERIES OF SYSTEMS IS MOVING EAST TOWARD THE PAC NW. THE
INITIAL WAVE IS SET TO MOVE INTO SE OREGON THIS EVENING AND INTO
SW IDAHO OVERNIGHT. LATEST GUIDANCE FROM THE 18Z NAM IS SLOWING
THE SYSTEM DOWN SIGNIFICANTLY...BUT WILL GO WITH THE OVERWHELMING
AGREEMENT OF THE GFS AND EC...ALONG WITH THE 12Z NAM AND THE
LATEST HRRR RUNS...ON THE PRECIP AREA GETTING THROUGH THE TREASURE
VALLEY BY 12Z. CLOUD COVER WILL BE EXTENSIVE TONIGHT...KEEPING
LOW TEMPS WELL ABOVE NORMAL. THE SECOND MAJOR WAVE IN THE SERIES
WILL MOVE THROUGH TUE NIGHT INTO WED...BRINGING ANOTHER ROUND OF
WIDESPREAD PRECIP. SNOW LEVELS FOR BOTH EVENTS WILL BE TOO HIGH TO
BRING SNOW TO THE VALLEYS...WITH HEIGHTS RANGING FROM 5000 FEET IN
THE NORTH TO 7500 FEET IN THE SOUTH TONIGHT...AND FROM 5500 FEET
IN THE NORTH TO 6500 FEET IN THE SOUTH FOR TUE NIGHT INTO WED
MORNING WHEN THE MAJORITY OF THE PRECIP ASSOCIATED WITH THE SECOND
SYSTEM WILL FALL. HEIGHTS WILL COME DOWN SWIFTLY THROUGH THE DAY
WED...CHANGING THE RAIN TO SNOW IN THE NORTH...BUT BY THAT TIME
MOST OF THE PRECIP WILL HAVE ENDED. TEMPS THROUGH THE SHORT TERM
WILL HAVE MINIMAL DIURNAL RANGE OWING TO CLOUD COVER. CHANGES FROM
THE PREVIOUS FORECAST WERE MINOR.
.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...MOSTLY DRY
CONDITIONS WEDNESDAY NIGHT AND THURSDAY WITH LINGERING SHOWERS
ALONG THE NEVADA BORDER AS A WEATHER SYSTEM EXITS TO THE EAST AND
A RIDGE OF HIGH PRESSURE BUILDS OFF THE WEST COAST. DRY CONDITIONS
WILL CONTINUE OVER THE FORECAST AREA FRIDAY THROUGH MONDAY. AS THE
RIDGE OF HIGH PRESSURE STRENGTHENS OVER THE FORECAST AREA
TEMPERATURE INVERSIONS WILL DEVELOP FRIDAY MORNING AND WILL
PERSIST THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. WITH
RESIDUAL MOISTURE FROM THE PRECIPITATION FROM TUESDAY AND
WEDNESDAY COMBINED WITH THE INVERSIONS WILL SEE AREAS OF VALLEY
FOG AND LOW STRATUS. TEMPERATURES WILL AVERAGE NEAR NORMAL BUT
VALLEY LOCATIONS UNDER THE INVERSION WILL LIKELY SEE TEMPERATURES
A FEW DEGREES BELOW NORMAL.
&&
.AVIATION...WIDESPREAD PRECIPITATION WILL MOVE INTO THE REGION
THIS EVENING AND WILL LINGER OVER THE AREA THROUGH TUESDAY. ONCE
PRECIPITATION BEGINS MOUNTAINS WILL BECOME OBSCURED ALONG WITH
AREAS OF MVFR AND LOCAL IFR CONDITIONS. SNOW LEVEL WILL BE AT OR
ABOVE 5K FEET MSL. LATEST TIMING OF PRECIPITATION STARTING AT TAF
SITES WILL BE AROUND 04Z FOR KBNO...KBKE AND KMYL...AROUND 10Z FOR
KBOI AND AROUND 15Z FOR KTWF AND KJER. SURFACE WINDS TONIGHT WILL
BE SOUTHEAST TO SOUTHWEST GENERALLY 10 KNOTS OR LESS. WINDS ALOFT
WILL BE SOUTHWESTERLY AROUND 15 KNOTS UP THROUGH 10K FEET MSL.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.
&&
$$
WEATHER.GOV/BOISE
SHORT TERM...SP
LONG TERM....JA/WH
AVIATION.....JA
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
233 PM EST MON NOV 18 2013
.SYNOPSIS...
A COLD FRONT WILL MOVE OFFSHORE THIS AFTERNOON. COOL HIGH PRESSURE
WILL THEN BUILD OVER THE REGION THROUGH THE REMAINDER OF THE WORK
WEEK. ANOTHER COLD FRONT WILL MOVE THROUGH THE AREA SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1245 PM MONDAY...MINOR UPDATE FOR LATEST TRENDS. PCPN HAS
DRIED UP BUT LATEST HRRR STILL INDICATES LINGERING SCT SHOWER THREAT
S COAST LATE AFTN...THUS WILL CONTINUE 30 POP REST OF AFTN THERE.
RAISED TEMPS A FEW DEGS WITH SOME SRN SECTIONS INTO UPR 70S.
/PREVIOUS DISCUSSION/
AS OF 705 AM MONDAY...HAVE SPED UP PRECIPITATION AS FRONT ALREADY
APPROACHING THE RALEIGH AREA AND BROKEN LINE OF SHOWERS MOVING
INTO OUR WESTERN CWA. HAVE SCALED BACK POPS TO 30 PCT AS COVERAGE
WILL BE LIMITED AND THINK THE BULK OF THE RAIN WILL BE THROUGH
THE AREA BY MID TO LATE MORNING. TEMPERATURES OFF TO A WARM
START THIS MORNING WITH SEVERAL STATIONS AROUND 70 AND EXPECT
READINGS INTO THE MID 70S AT MANY SITES AHEAD OF THE FRONT. BY
MID- AFTERNOON...EXPECTING GUSTY N/NNE WINDS WITH TEMPS LEVELING
OFF THEN FALLING LATE DURING THE DAYLIGHT HOURS.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
AS OF 355 AM MONDAY...SKIES SHOULD BECOME CLEAR BY SHORTLY AFTER
DARK WITH NORTHERLY BREEZES BRINGING IN COOLER AND DRIER AIR. FOR
LOW TEMPERATURES TONIGHT...MOST AREAS AWAY FROM THE IMMEDIATE
COAST WILL BE IN THE LOW TO MID 40S WITH TEMPERATURES RIGHT AROUND
50 OVER THE OUTER BANKS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
AS OF 230 PM MON...NO SIGNIFICANT CHANGES NEEDED TO FORECAST AT
THIS TIME. SFC HIGH PRESSURE WILL BUILD OVER THE NE US TUE NIGHT
THROUGH LATE WEEK...EXTENDING SOUTHWARD INTO THE SE STATES...WITH
UPPER RIDGING OVER THE SE. GRADUAL TEMP WARMUP EXPECTED THROUGH
THE WEEK WITH BUILDING HEIGHTS. GOOD RADIATIONAL COOLING
CONDITIONS EXPECTED TUE NIGHT WITH CLEAR SKIES AND LIGHT
WINDS...WITH LOWS IN THE LOWER 30S TO LOW/MID 40S FOR THE OUTER
BANKS. BY THU EXPECT TEMPS NEAR NORMAL IN THE LOW/MID 60S. A COLD
FRONT WILL MOVE THROUGH EASTERN NC SATURDAY WITH INCREASING
MOISTURE AND LIFT...WILL CONTINUE CHANCE POPS SAT THROUGH SAT
NIGHT...SLOWLY TAPERING OFF FROM W TO E EARLY SUN MORNING. STRONG
HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT SUN AND MON. MUCH
COOLER TEMPS EXPECTED BEHIND THE FRONT. LOW LEVEL THICKNESS
VALUES SUPPORT HIGHS IN THE UPPER 40S/LOWER 50S WITH OVERNIGHT
LOWS IN THE LOW/UPPER 30S.
&&
.AVIATION /19Z MONDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH TUESDAY/...
AS OF 1230 PM MONDAY...HIGH CONFIDENCE OF VFR CONDITIONS WILL
DOMINATE THE TAF PERIOD. ONCE THE COLD FRONT CROSSES THE
AREA...DRIER AIR WILL AID TO DISSIPATE THE REMAINING CLOUD COVERAGE
IN THE AREA. HIGH PRESSURE WILL BUILD OVERNIGHT...RESULTING WITH A
TIGHTEN PRESSURE GRADIENT AND INHIBITING ANY FOG/LOW STRATUS
DEVELOPMENT. WINDS WILL INCREASE TO 10 GUSTING UP TO 15 KT TOMORROW
MORNING WITH MOSTLY CLEAR SKIES.
LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 230 PM MON...PREDOMINATE VFR CONDITIONS EXPECTED THROUGH THE
PERIOD. A COLD FRONT WILL MOVE THROUGH THE AREA SATURDAY...WITH
PERIODS OF SUB-VFR CONDITIONS POSSIBLE.
&&
.MARINE...
.SHORT TERM /THROUGH TONIGHT/...
AS OF 1245 PM MONDAY...NO CHANGES WITH UPDATE.
/PREVIOUS DISCUSSION/
AS OF 705 AM MONDAY...NO MAJOR CHANGES TO CURRENT MARINE FORECAST
AS SOUTHWEST WINDS OF 15 TO 20 KNOTS SHOULD GRADUALLY BECOME NW BY
EARLY AFTERNOON. EVEN THOUGH WIND AND WAVE MODELS INDICATE THAT
WINDS/SEAS WILL DIMINISH BELOW SMALL CRAFT ADVISORY FOR A FEW
HOURS LATE THIS AFTERNOON AND EVENING...WINDS AND SEAS ABRUPTLY
INCREASE WITH STRONG CAA BEHIND COLD FRONT TONIGHT AND HAVE OPTED
TO KEEP SMALL CRAFT ADV FOR THE COASTAL WATERS TODAY...TONIGHT AND
INTO MID WEEK GIVEN THE GUSTY N/NE WINDS AND ROUGH SEAS. THE
FRONTAL PASSAGE SHOULD OCCUR FOR THE COASTAL WATERS AROUND 18Z OR
SO WITH WINDS VEERING FROM S/SW EARLY THIS MORNING TO WNW/NW BY
EARLY AFTERNOON.
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 230 PM MON...SCA CONDITIONS TO START OFF THE PERIOD AND
CONTINUE THROUGH MID/LATE WEEK. SFC HIGH PRESSURE WILL CONTINUE TO
BUILD NORTH TUE NIGHT EXTENDING OVER THE AREA THROUGH LATE WEEK.
THIS COMBINED WITH CAA WILL RESULT IN N/NE WINDS 15-25KT TUE NIGHT
BECOMING NE 15-20KT WED. ELEVATED SEAS OF 4-6FT LIKELY CONTINUE
THROUGH THU. NE FLOW CONTINUES THROUGH THU NIGHT...SLOWLY VEERING
AND BECOMING SLY FRI NIGHT AS COLD FRONT APPROACHES FROM THE WEST. A
COLD FRONT WILL MOVE THROUGH THE WATERS LATE SAT/SAT NIGHT. SW
WINDS WILL INCREASE TO 15-25KT AHEAD OF THE FRONT SAT...BECOMING
NW BEHIND THE FRONT.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 AM TO 10 PM EST TUESDAY FOR AMZ135.
SMALL CRAFT ADVISORY FROM 1 AM TO 4 PM EST TUESDAY FOR AMZ130.
SMALL CRAFT ADVISORY UNTIL 4 PM EST THURSDAY FOR AMZ152-154-
156-158.
SMALL CRAFT ADVISORY UNTIL 10 AM EST THURSDAY FOR AMZ150.
&&
$$
SYNOPSIS...CTC
NEAR TERM...JBM/CTC
SHORT TERM...CTC
LONG TERM...CQD
AVIATION...BM/CQD
MARINE...JBM/CTC/CQD
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
100 PM EST MON NOV 18 2013
.SYNOPSIS...
A COLD FRONT WILL MOVE OFFSHORE THIS AFTERNOON. COOL HIGH PRESSURE
WILL THEN BUILD OVER THE REGION THROUGH THE REMAINDER OF THE WORK
WEEK. ANOTHER COLD FRONT WILL MOVE ACROSS THE AREA SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1245 PM MONDAY...MINOR UPDATE FOR LATEST TRENDS. PCPN HAS
DRIED UP BUT LATEST HRRR STILL INDICATES LINGERING SCT SHOWER THREAT
S COAST LATE AFTN...THUS WILL CONTINUE 30 POP REST OF AFTN THERE.
RAISED TEMPS A FEW DEGS WITH SOME SRN SECTIONS INTO UPR 70S.
/PREVIOUS DISCUSSION/
AS OF 705 AM MONDAY...HAVE SPED UP PRECIPITATION AS FRONT ALREADY
APPROACHING THE RALEIGH AREA AND BROKEN LINE OF SHOWERS MOVING
INTO OUR WESTERN CWA. HAVE SCALED BACK POPS TO 30 PCT AS COVERAGE
WILL BE LIMITED AND THINK THE BULK OF THE RAIN WILL BE THROUGH
THE AREA BY MID TO LATE MORNING. TEMPERATURES OFF TO A WARM
START THIS MORNING WITH SEVERAL STATIONS AROUND 70 AND EXPECT
READINGS INTO THE MID 70S AT MANY SITES AHEAD OF THE FRONT. BY
MID- AFTERNOON...EXPECTING GUSTY N/NNE WINDS WITH TEMPS LEVELLING
OFF THEN FALLING LATE DURING THE DAYLIGHT HOURS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
AS OF 355 AM MONDAY...SKIES SHOULD BECOME CLEAR BY SHORTLY AFTER
DARK WITH NORTHERLY BREEZES BRINGING IN COOLER AND DRIER AIR. FOR
LOW TEMPERATURES TONIGHT...MOST AREAS AWAY FROM THE IMMEDIATE
COAST WILL BE IN THE LOW TO MID 40S WITH TEMPERATURES RIGHT AROUND
50 OVER THE OUTER BANKS.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
AS OF 3 AM MON...STRONG SURFACE RIDGING WILL BUILD ACROSS EASTERN
NC FROM THE NORTH TUES INTO WED WHILE UPPER RIDGING WILL ALSO
BUILD OVER THE REGION FROM THE WEST. MODEST CAA WITH LOW LEVEL
THICKNESSES FALLING TO 1315-1525 METERS EACH DAY WILL YIELD TEMPS
7-8 DEGREES BELOW CLIMO FOR MID NOVEMBER WITH HIGHS ONLY IN THE
MID/UPPER 50S. OVERNIGHT LOWS WILL REACH NEAR FREEZING TUES NIGHT
THEN MODERATE INTO THE UPPER 30S WED NIGHT. GUIDANCE CONTINUES TO
INDICATE WEAK SHORTWAVE ALOFT IN MEAN WESTERLY FLOW MAY PRODUCE
SOME LIGHT SHOWERS FOR COASTAL REGIONS WED AND HAVE MAINTAINED
SLIGHT CHANCE FOR THE CENTRAL OBX/COASTAL WATERS.
BY WED NIGHT...THE SURFACE RIDGE TO THE NORTH WILL SHIFT OVER NEW
ENGLAND AND NOSE SOUTH OVER THE REGION...PRODUCING NE FLOW. RIDGE
THEN SHIFTS OFF THE SOUTHERN NEW ENGLAND COAST THURS/FRI WITH
UPPER RIDGING PERSISTING OVER THE REGION. 850 MB FLOW BECOMES SSW
THUR/FRI WITH SURFACE FLOW REMAINS NE YIELDING CLOUDS AND POSSIBLE
PRECIP MAINLY NEAR THE COAST. SURFACE RETURN FLOW SETS UP FRI AS
THE HIGH SHIFTS OFFSHORE AND A COLD FRONT APPROACHES FROM THE NW
ALLOWING LOW LEVEL THICKNESSES TO BUILD 1360-1370 METERS WITH
TEMPS IN THE MID 60S. KEPT FRI DRY AND BEGAN TREND OF INCREASING
POPS FRI NIGHT AS FRONT SLOWLY SAGS SE OVER THE REGION. SAT SHOULD
REMAIN MILD TEMPERATURE-WISE WITH CHANCE POPS/SCATTERED SHOWERS.
COLD FRONT WILL PUSH OFF THE COAST SAT NIGHT WITH STRONG HIGH
PRESSURE BUILDING IN BEHIND THE FRONT ON SUN. TEMPS SUN WILL BE
COOLER WITH HIGHS IN THE LOW TO MID 50S.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH 18Z TUESDAY/...
AS OF 1230 PM MONDAY...HIGH CONFIDENCE OF VFR CONDITIONS WILL
DOMINATE THE TAF PERIOD. ONCE THE COLD FRONT CROSSES THE
AREA...DRIER AIR WILL AID TO DISSIPATE THE REMAINING CLOUD COVERAGE
IN THE AREA. HIGH PRESSURE WILL BUILD OVERNIGHT...RESULTING WITH A
TIGHTEN PRESSURE GRADIENT AND INHIBITING ANY FOG/LOW STRATUS
DEVELOPMENT. WINDS WILL INCREASE TO 10 GUSTING UP TO 15 KT TOMORROW
MORNING WITH MOSTLY CLEAR SKIES.
LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 305 AM MON...VFR CONDITIONS WILL PREVAIL THROUGH THE LONG
TERM. HIGH PRESSURE WILL BUILD OVER THE REGION TUES THROUGH MID
WEEK WITH OVERALL DRY AIRMASS AND THUS NO IMPACTS ON AVIATION
EXPECTED.
&&
.MARINE...
.SHORT TERM /THROUGH TONIGHT/...
AS OF 1245 PM MONDAY...NO CHANGES WITH UPDATE.
/PREVIOUS DISCUSSION/
AS OF 705 AM MONDAY...NO MAJOR CHANGES TO CURRENT MARINE FORECAST
AS SOUTHWEST WINDS OF 15 TO 20 KNOTS SHOULD GRADUALLY BECOME NW BY
EARLY AFTERNOON. EVEN THOUGH WIND AND WAVE MODELS INDICATE THAT
WINDS/SEAS WILL DIMINISH BELOW SMALL CRAFT ADVISORY FOR A FEW
HOURS LATE THIS AFTERNOON AND EVENING...WINDS AND SEAS ABRUPTLY
INCREASE WITH STRONG CAA BEHIND COLD FRONT TONIGHT AND HAVE OPTED
TO KEEP SMALL CRAFT ADV FOR THE COASTAL WATERS TODAY...TONIGHT AND
INTO MID WEEK GIVEN THE GUSTY N/NE WINDS AND ROUGH SEAS. THE
FRONTAL PASSAGE SHOULD OCCUR FOR THE COASTAL WATERS AROUND 18Z OR
SO WITH WINDS VEERING FROM S/SW EARLY THIS MORNING TO WNW/NW BY
EARLY AFTERNOON.
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 310 AM MON...A PROLONGED PERIOD OF SMALL ADVISORY CONDITIONS
ARE EXPECTED THROUGH THE PERIOD. SURFACE RIDGE SHIFTS OVER NEW
ENGLAND THEN OFF THE NEW ENGLAND COAST BY LATE WEEK. NORTHERLY WINDS
REMAIN 15-25 KT TUES DUE TO STRONG CAA...THEN WINDS SHIFT NE TUES
NIGHT INTO WED AND BECOME 10-20 KT. GRADIENT DIMINISHES FURTHER
WED/THURS WITH WINDS DIMINISH 10-15 KT AND SLOWLY VEERING ENE
THROUGH THURS. SEAS REMAIN ELEVATED 5-7 FT TUES INTO THURS. SEAS
SHOULD SUBSIDE BELOW 6 FT FOR THE SOUTHERN WATERS BY WED THEN FOR
ALL WATERS BY THURS NIGHT/FRI MORNING.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST WEDNESDAY FOR
AMZ150-152- 154-156.
SMALL CRAFT ADVISORY UNTIL 7 PM EST TUESDAY FOR AMZ158.
&&
$$
SYNOPSIS...CTC
NEAR TERM...CTC/JBM
SHORT TERM...CTC
LONG TERM...DAG
AVIATION...CTC/BM
MARINE...CTC/DAG/JBM