Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 10/21/13

AREA FORECAST DISCUSSION

NWS MOUNT HOLLY NJ

 345 PM EDT SAT OCT 19 2013

.SYNOPSIS...
LOW PRESSURE TRACKING ACROSS SOUTHEASTERN CANADA WILL SEND A WEAK
COLD FRONT THROUGH OUR REGION TONIGHT. HIGH PRESSURE TO OUR
SOUTHWEST WILL THEN OVERSPREAD THE MID ATLANTIC SUNDAY BEFORE
PROGRESSING OFFSHORE MONDAY. ANOTHER COLD FRONT IS THEN FORECAST TO
CROSS THE AREA DURING TUESDAY, FOLLOWED BY POSSIBLE LOW PRESSURE
MOVING ACROSS THE REGION WEDNESDAY INTO WEDNESDAY NIGHT. FOR THE END
OF THE WEEK, STRONG HIGH PRESSURE BUILDS TO OUR WEST ACROSS THE
PLAINS AND MIDWEST STATES.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
A COMBINATION OF THE GFS AND WRF-NMMB INITIALIZATION LOOKED THE
BEST OFF THE 12Z SOUNDINGS THIS MORNING. ALL THE MODELS ARE VERIFYING
QUITE WELL WITH THEIR 6HR QPF FORECASTS ENDING AT 18Z AND THEY ALL
HAVE SIMILAR RESULTS FOR OUR CWA. THEY ALL HAVE A BIFURCATED LOOK TO
THE PCPN MASS FIELDS AS THE EXIT REGION OF THE 250MB JET AND STRONG
MID LEVEL QVEC CONVERGENCE SEPARATE FROM EACH OTHER. WE ARE LEFT
WITH A LIGHT PCPN EVENT OF SHORT MEASURABLE DURATION MAINLY
CONCENTRATED IN THE EVENING HOURS. THIS IS A LEVEL LOWER TO WHAT
OCCURRED ON THURSDAY NIGHT EXCEPT THIS TIME WE HAVE NO THUNDER IN
OUR FORECAST (INSTABILITY IS EVEN LESS AND EVEN FARTHER REMOVED TO
THE NORTHWEST). MOST PLACES SHOULD MEASURE ONE TENTH OF AN INCH OR
LESS TONIGHT.

THE TIMING OF THE HIEST POPS ARE CLOSE TO THE HRRR OUTPUT WHICH TOO
HAS BEEN DOING RATHER WELL TODAY. AROUND THE HIGHEST POP TIME THIS
EVENING THERE COULD BE SOME SPRINKLES WHICH FOR THE SAKE OF
SIMPLICITY WAS CARRIED AS LOWER CHANCE POPS.

LIKE THURSDAY NIGHT, THE FORECAST SOUNDINGS ARE SHOWING SOME
GUSTINESS AFTER THE FRONT MOVES THROUGH (3Z-6Z MOST PLACES). THE
WRF-NMMB WAS TOO BOLD TWO NIGHTS AGO AND GIVEN HOW MUCH MORE BENIGN
THE GFS FCST SOUNDINGS ARE, WE SPLIT THE DIFFERENCE. WE EXPECT MIN
TEMPERATURES TO REMAIN RELATIVELY UP (AND OCCUR VERY LATE AT NIGHT,
IF NOT AFTER SUNRISE SUNDAY MORNING) BECAUSE OF THE WINDS. WE ARE
CLOSER TO THE HIGHER NAM GUIDANCE, ESPECIALLY EAST.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
A DELIGHTFUL OCTOBER WEATHER DAY IS FORECAST FOR SUNDAY WITH AMPLE
SUNSHINE AND TEMPERATURES AT OR SLIGHTLY COOLER THAN NORMAL FOR
MAXES. A SPLIT BETWEEN THE WRF-NMMB AND GFS AS TO WHETHER THE
CONVECTIVE TEMP WILL BE REACHED. WE ARE GETTING CLOSER TO THE
STRATOCU SEASON OF NOVEMBER, SO WE SIDED WITH THE WRF AND KEPT SOME
CLOUD COVERAGE (STILL ON THE SUNNIER SIDE OF THE FENCE) IN THE SKY
GRIDS. THERE WILL BE SOME GUSTINESS FROM THE WEST TO NORTHWEST
WINDS. WE ARE FORECASTING IT TO DECREASE AS THE AFTERNOON CONTINUES
AND HIGH PRESSURE GETS CLOSER. MAX TEMPS WERE BASED ON A 925MB/850MB
ADIABATIC AVERAGE BECAUSE OF THE DOWNSLOPING NORTHWEST FLOW. THIS
WAS AT OR SLIGHTLY ABOVE STAT GUIDANCE WHICH WAS PRETTY PRETTY CLOSE
INDEED.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
A QUIET START TO THE LONG TERM AS SURFACE HIGH PRESSURE WILL BE OVER
THE REGION SUNDAY NIGHT BEFORE EVENTUALLY MOVING EAST AND OFFSHORE
DURING MONDAY. DRY CONDITIONS AND FAIRLY SEASONAL MID-OCTOBER
TEMPERATURES ARE EXPECTED WITH LOWS SUNDAY NIGHT RANGING FROM THE
MID 30S NORTH TO THE MID 40S SOUTH AND DAYTIME HIGHS MONDAY MAINLY
IN THE 60S.

AS SURFACE HIGH PRESSURE EXITS OFFSHORE MONDAY, LOW PRESSURE WILL BE
SLOWLY MOVING ACROSS THE GREAT LAKES AND INTO SOUTHEAST CANADA, WITH
ITS TRAILING COLD FRONT APPROACHING OUR REGION FROM THE OHIO VALLEY.
THIS COLD FRONT IS FORECAST TO TRACK THROUGH OUR AREA DURING
TUESDAY, BUT THE BEST FORCING WILL BE FARTHER TO THE NORTH, AND WITH
LIMITED ATMOSPHERIC MOISTURE ACROSS THE AREA, ANY PRECIPITATION
ASSOCIATED WITH THE FRONTAL PASSAGE LOOKS TO FALL APART AS IT NEARS
OUR REGION. WE HAVE, HOWEVER, KEPT SLIGHT CHANCE POPS FOR ISOLATED
SHOWERS IN PLACE FOR OUR NORTHWEST ZONES, AS THERE MAY BE JUST
ENOUGH LIFT AND MOISTURE FOR A TIME.

THE NEXT FEATURE OF INTEREST WILL BE POSSIBLE LOW PRESSURE MOVING
ACROSS OUR REGION DURING THE WEDNESDAY TO WEDNESDAY NIGHT PERIOD.
THERE IS A LITTLE BIT MORE MODEL CONSISTENCY WITH THIS FEATURE AS
THE ECMWF AND GFS SHOW AN INITIAL SHORTWAVE/CLIPPER-TYPE SYSTEM
MOVING SOUTH OUT OF CENTRAL CANADA EARLY TUESDAY AND REACHING THE
OHIO VALLEY REGION LATER TUESDAY NIGHT, WITH AN OVERALL
STRENGTHENING MID LEVEL TROUGH DEVELOPING. THIS DISTURBANCE IS
PROGGED TO THEN CROSS THE APPALACHIANS AND OUR REGION WEDNESDAY INTO
WEDNESDAY NIGHT, WITH THE ECMWF AND GFS THEN INDICATING
STRENGTHENING SURFACE LOW PRESSURE AS IT EMERGES OFF THE MID
ATLANTIC COAST WEDNESDAY NIGHT AND TRACKS NORTHEAST OFF THE NEW
ENGLAND SEABOARD BY EARLY THURSDAY MORNING. MODEL THICKNESSES
DECREASE THROUGH THIS PERIOD, AND DEPENDING ON THE TIMING OF PRECIP,
SOME MIXED PRECIPITATION MAY BE IN STORE FOR THE HIGHER ELEVATIONS
THROUGH THE POCONOS. WE HAVE KEPT LOW POPS IN PLACE WITH THE PASSAGE
OF THIS SYSTEM AND THE IDEA OF A SMALL WINDOW OF MIXED PRECIP FOR
OUR FAR NORTHWEST AREAS. AS CONSISTENCY IN MODEL RUNS IS STILL
WAVERING AT THIS TIME, CONFIDENCE REGARDING THE TIMING AND
DEVELOPMENT OF THIS SYSTEM IS BELOW AVERAGE.

ONCE THIS SYSTEM PASSES EAST AND OFFSHORE, A COOL NORTHWEST FLOW
SETS UP ACROSS THE REGION THROUGH THE END OF THE WEEK AS MID LEVEL
TROUGHING STRENGTHENS AND STRONG SURFACE HIGH PRESSURE BUILDS TO OUR
WEST ACROSS THE PLAINS AND MIDWEST STATES. BELOW NORMAL TEMPERATURES
ARE EXPECTED FOR OUR REGION THROUGH THIS TIMEFRAME, AS MAXIMUM TEMPS
WILL ONLY BE IN THE 50S THURSDAY THROUGH SATURDAY FOR MUCH OF THE
AREA. OVERNIGHT LOWS IN THE 30S WILL BE ON TAP, WITH SOME UPPER 20S
POSSIBLE THROUGH THE HIGHER TERRAIN INTO THE POCONOS AND NORTHWEST
NEW JERSEY.

&&

.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THE 18Z TAFS CARRIED A PERIOD OF MVFR CONDITIONS THIS EVENING AS
SHOWERS MOVE THROUGH.

FOR THE REST OF THIS AFTERNOON VFR CONDITIONS ARE FORECAST WITH
LOWERING CIGS. THE FIRST BAND OF SHOWERS SO FAR HAS REMAINED JUST
SOUTHEAST OF KMIV AND KACY. CIGS THERE MIGHT COME CLOSE TO MVFR
LEVELS. SOUTH WINDS SHOULD AVERAGE AROUND 10 KTS. THERE MIGHT BE
SOME GUSTINESS, BUT CONFIDENCE NOT HIGH ENOUGH TO INCLUDE.

FOR TONIGHT, WE CONTINUE THE PREVIOUS FORECAST IDEA OF A PERIOD OF
MVFR CONDITIONS MAINLY DUE TO CIGS AS SHOWERS MOVE THROUGH
(APPROXIMATELY 00Z TO 03Z). SOUTH WINDS SHOULD CONTINUE UNTIL THE CFP.

THE CFP IS FORECAST TO MOVE THROUGH 03Z-06Z FROM WEST TO EAST. VFR
CIGS SHOULD BE LIFTING AND WE HAVE ACCEPTED A COMPROMISE APPROACH
TO GUIDANCE SUGGESTIONS AS TO HOW MUCH GUSTINESS FOR A COUPLE OF
HOURS WILL OCCUR FOLLOWING THE CFP.

OVERNIGHT SKIES WILL BECOME CLEAR AND TOO MUCH WIND FOR ANY FOG
TO FORM.

ON SUNDAY VFR CONDITIONS WITH FEW TO SCATTERED CUMULUS CLOUDS
AROUND 5K-6K. SOME GUSTINESS SHOULD RETURN (20 - 25 KTS) AS WEST
TO NORTHWEST WINDS CONTINUE.

OUTLOOK...
SUNDAY NIGHT THROUGH TUESDAY...MAINLY VFR CONDITIONS WITH WINDS
BECOMING SOUTH TO SOUTHWEST.

WEDNESDAY...MOSTLY VFR. POSSIBLE SUB-VFR CONDITIONS IN
ISOLATED/SCATTERED SHOWERS.

THURSDAY...MAINLY VFR WITH GUSTY WEST-NORTHWEST WINDS.

&&

.MARINE...
THE SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR A QUICK SHOT OF GUSTY
WINDS BEHIND THE COLD FRONT TONIGHT INTO SUNDAY MORNING. THE LATEST MODEL
RUN IS DECREASING THE WINDS FASTER, SO AS LONG AS SEAS SUBSIDE
(WHICH WE THINK BECAUSE OF THE OFFSHORE FLOW AND SHORT DURATION), WE
DO NOT ENVISION AN EXTENSION BEYOND THE CURRENT ADVISORY EXPIRATION
TIME. WE LEFT UPPER DELAWARE BAY OUT OF THE ADVISORY FOR NOW AS THE
TIGHTEST GRADIENT THERE OCCURS BEFORE THE LARGER AIR AND WATER
TEMPERATURE DIFFERENTIAL.

OUTLOOK...
HIGH PRESSURE WILL BE IN PLACE ACROSS THE REGION INTO SUNDAY NIGHT,
BEFORE GRADUALLY PROGRESSING OFFSHORE DURING MONDAY. THROUGH THIS
TIMEFRAME, SUB-ADVISORY CONDITIONS ARE ANTICIPATED FOR OUR COASTAL
WATERS AND THROUGH DELAWARE BAY. A COLD FRONT WILL THEN APPROACH AND
CROSS THE REGION DURING TUESDAY, FOLLOWED BY POSSIBLE LOW PRESSURE
WEDNESDAY INTO WEDNESDAY NIGHT. AT THIS TIME, SUB-ADVISORY
CONDITIONS ARE EXPECTED TO CONTINUE; ALTHOUGH, SOME WIND GUSTS TO
AROUND 20 KNOTS ARE POSSIBLE FOR OUR COASTAL WATERS. AN INCREASING
WEST-NORTHWEST FLOW TAKES SHAPE THURSDAY INTO THURSDAY NIGHT, WITH
POSSIBLE SCA CONDITIONS DEVELOPING.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 2 PM EDT SUNDAY
     FOR ANZ431-450>455.

&&

$$
SYNOPSIS...KLINE
NEAR TERM...GIGI
SHORT TERM...GIGI
LONG TERM...KLINE
AVIATION...GIGI/KLINE
MARINE...GIGI/KLINE







AREA FORECAST DISCUSSION

NWS MELBOURNE FL

 1005 PM EDT SUN OCT 20 2013

.DISCUSSION...
WEAK STATIONARY FRONT DRAPED OVER THE CENTRAL PENINSULA THIS
EVENING...EXTENDING ROUGHLY FROM TAMPA BAY TO CAPE CANAVERAL.
SLIGHTLY TIGHTER PGRAD ACRS THE AREA THAN IN RECENT DAYS AS THE
FRONTAL TROF IS INTERACTS AXIS OF THE SUBTROPICAL ATLC RIDGE OVER
THE NRN BAHAMAS...WSR-88D VAD WIND PROFILERS AND THE USAF 915HZ
PROFILER ALL MEASURING A STEADY NRLY FLOW THRU 3KFT.

THE FRONTAL TROF HAS PUSHED A FAIR AMOUNT OF MOISTURE INTO THE FL
PENINSULA. EVENING RAOBS MEASURING PWATS FROM 1.5" AT KTBW...TO 1.7"
AT KJAX.. TO 2.1" AT KMFL. FOG POTENTIAL WILL BE LIMITED...
HOWEVER...DUE TO THE STRONGER WINDS ALOFT AND A MID/UPR LVL CLOUD
DECK OVER THE PANHANDLE THAT SHOULD PRESS INTO THE NRN PENINSULA
OVERNIGHT.

THERMODYNAMIC PROFILE IS QUITE HOSTILE FOR NOCTURNAL PRECIP: H70
TEMPS BTWN 9-10C...H50 TEMPS ARND -5C...RESULTING IN MID LVL LAPSE
RATES ARND 5C/KM. RUC ANALYSIS DOES SHOW GOOD UPR LVL DIVERGENCE
ASSOCD WITH THE H30-H20 JET MAX LIFTING OUT OF THE DEEP SOUTH...BUT
ALSO SHOWS A DEARTH OF MID LVL VORTICITY OVER CENTRAL FL THAT WILL
ELIMINATE ANY POTENTIAL FOR MID LVL LIFT. EVEN ISENTROPIC ANALYSIS
INDICATES A NEUTRAL STATE AT BEST.

ISOLD SHRAS S OF THE I-4 CORRIDOR SHOULD DISSIPATE WITHIN THE HR...
WILL RELEASE THE EVENING UPDATE TO REMOVE PRECIP ONCE THEY DO. NO
OTHER SIG CHANGES NECESSARY.

&&

.AVIATION...
THRU 21/08Z...VFR ALL SITES. BTWN 21/08Z-20/14Z...PATCHY MVFR/LCL
IFR VSBYS IN BR. BTWN 21/14Z-21/17Z...VFR ALL SITES. AFT 21/17Z...
CHC MVFR SHRAS/SLGT CHC IFR TSRAS ALL SITES.

&&

.MARINE...
STATIONARY FRONTAL TROF OVER THE CENTRAL PENINSULA INTERACTING WITH
THE ATLC SFC RIDGE OVER THE NRN BAHAMAS TO GENERATE A SLIGHTLY
TIGHTER PGRAD ACRS THE LCL ATLC THAN SAT NIGHT. GENTLE TO MODERATE
N/NE BREEZE N OF THE CAPE...LIGHT TO GENTLE E/NE BREEZE S OF THE
CAPE. DATA BUOYS MEASURING STEADY STATE CONDITIONS...SEAS AOB 2FT
NEARSHORE AND 2-3FT OFFSHORE...MAINLY IN A 9SEC BACKGROUND SWELL.
SEAS MAY BECOME A BIT CHOPPIER N OF THE CAPE AS BUOY012 HAS MEASURED
5SEC DOMINANT WAVE PDS FOR THE PAST SVRL HRS...ASSOCD WITH THE
STRONGER SFC WNDS.

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.

&&

$$

SHORT TERM/AVIATION...BRAGAW
LONG TERM/IMPACT WX...LASCODY






AREA FORECAST DISCUSSION

NWS TAMPA BAY RUSKIN FL

 745 PM EDT SUN OCT 20 2013

.UPDATE (TONIGHT AND MONDAY)...
23Z WATER VAPOR AND H4 RAP ANALYSIS SHOWING THAT MUCH OF THE CONUS
REMAINS UNDER AN EXPANSIVE UPPER TROUGH. WITHIN THE PARENT
TROUGH...2 DISTINCT VORTICITY MAXIMUM CAN BE FOUND...WITH ONE
ENTERING THE CANADIAN MARITIMES REGION...AND ANOTHER PIVOTING SOUTH
AND EAST TOWARD THE UPPER MS VALLEY/WESTERN GREAT LAKES. THIS SECOND
PIECE OF ENERGY IS ASSOCIATE WITH SOME RATHER CHILLY AIR WITH MANY
STATIONS ACROSS NORTHERN MN/WI REPORTING SNOW OR MIXED PRECIP THIS
HOUR. NONE OF THAT BUSINESS FOR US AS THE FLORIDA PENINSULA RESIDES
IN THE TRANSITION ZONES BETWEEN THE MAIN LONGWAVE TROUGH TO OUR
NORTHWEST AND UPPER RIDGING OVER THE FL STRAITS/BAHAMAS. WV IMAGERY
SHOWS A ZONE OF DEEPER MID/UPPER LEVEL MOISTURE STREAMING
NORTHEASTWARD AHEAD OF THE TROUGH OVER THE NE GULF COAST AND
NORTHERN FLORIDA. FURTHER SOUTH...THE ATMOSPHERIC COLUMN IS MUCH
DRIER AS ONE APPROACHES THE RIDGE AXIS.

AT THE SURFACE...WAS ANOTHER WARM LATE OCTOBER DAY WITH MOST
STATIONS REPORTING HIGH TEMPS WELL UP INTO THE 80S. WEAK DECAYING
FRONT IS CURRENTLY ALIGNED NEAR THE I-4 CORRIDOR AND WILL BECOME
LESS AND LESS DISTINCT WITH TIME. DO SEE A DECENT MOISTURE GRADIENT
TO THE NORTH OF THIS BOUNDARY. DEWPOINTS FROM TAMPA AREA SOUTHWARD
ARE IN THE LOWER 70S...AND THEN FALL TO THE MIDDLE 60S UP TOWARD
GAINESVILLE...AND DOWN INTO THE UPPER 50S IN SOUTHERN GA. WILL SEE
SOME REBOUND IN THESE VALUES ASSOCIATED WITH THE DIURNAL RECOVERY
AFTER SUNSET...BUT IT STILL SHOWS JUST HOW CLOSE THE DRIER AIR IS.
SO CLOSE...YET SO FAR FOR MOST OF US.

THE WARM TEMPERATURES AND LOW LEVEL MOISTURE COMBINED WITH ENHANCED
FOCUS FROM THE SEA-BREEZE IS FORCING A FEW MAINLY INLAND SHOWERS
THIS EVENING. THESE SHOWERS AND EVEN A RUMBLE OF THUNDER EAST OF THE
I-75 CORRIDOR SHOULD LINGER FOR A COUPLE MORE HOURS WHILE SOME
RESIDUAL TERRESTRIAL INSTABILITY REMAINS...AND THEN FADE. THE
REMAINDER OF THE NIGHT SHOULD BE MAINLY DRY AND SEASONABLE. MANY OF
THE GUIDANCE MEMBERS ARE SUGGESTING THAT FOG MAY BECOME AN ISSUE
LATER TONIGHT...ESPECIALLY TOWARD DAWN. CAN`T ARGUE WITH THESE
MEMBERS...ESPECIALLY OVER OUR SOUTHERN ZONES CONSIDERING THE LOW
LEVEL MOISTURE IN PLACE...AND THE BETTER COLUMN SUPPRESSION IN
PROXIMITY TO THE UPPER RIDGE. AFTERNOON FORECAST PACKAGE ADDED
PATCHY TO AREAS OF FOG TO THE FORECAST AFTER 08Z...AND WILL LEAVE IN
FOR THIS UPDATE.

OVERALL SYNOPTIC PATTERN DOES NOT CHANGE MUCH INTO THE DAY ON MONDAY
AND THEREFORE...NEITHER WILL THE FORECAST. A DRY MORNING AND EARLY
AFTERNOON WILL EVENTUALLY PRODUCE A SEA-BREEZE AND ENOUGH
INSTABILITY TO SUPPORT A FEW MAINLY INLAND SHOWERS. VERY SIMILAR TO
SUNDAY AFTERNOON/EARLY EVENING. HAVE A GOOD NIGHT...AND LOOK OUT FOR
THE AREAS OF FOG/LOW VISIBILITY DURING THE MONDAY MORNING COMMUTE.

&&

.AVIATION...
21/00Z-22/00Z. LIMITED AFTERNOON CONVECTION GENERALLY EAST OF
TERMINALS WITH NO IMPACT THIS EVENING. MAIN CONCERN IS BR AND LOW
CIGS WITH ALL TERMINAL AT MVFR VSBY/CIG AFTER MIDNIGHT THROUGH
SUNRISE...BRIEF IFR AT LAL AND PGD. AFTERNOON SEA BREEZE WILL
COLLAPSE TO LIGHT VARIABLE BUT MOSTLY NE OR EAST WINDS THROUGH MON
MORNING THEN SHIFTING TO ONSHORE IN THE AFTERNOON. ISOLATED SHRA
AFTER 18Z.

&&

.MARINE...
A WEAK PRESSURE PATTERN WILL REMAIN IN PLACE OVERNIGHT THROUGH
TUESDAY NIGHT...KEEPING WINDS AND SEAS BELOW HEADLINE THRESHOLDS. A
STRONG COLD FRONT WILL MOVE THROUGH WEDNESDAY AND WEDNESDAY NIGHT
WITH HIGH PRESSURE THEN BUILDING NORTH OF THE REGION THROUGH THE END
OF THE WORK WEEK. THIS STRONGER COLD FRONT WILL LIKELY RESULT IN
WINDS AND/OR SEAS APPROACHING CAUTIONARY AND PERHAPS ADVISORY LEVELS
DURING THE MID TO LATE WEEK TIME FRAME.

&&

.PRELIMINARY POINT TEMPS/POPS...
TPA  73  88  73  87 /  10  20  10  20
FMY  73  90  73  89 /  10  20  10  20
GIF  71  91  70  89 /  20  30  20  30
SRQ  72  86  72  86 /  10  10  10  20
BKV  68  88  67  87 /  10  30  20  20
SPG  76  88  75  87 /  10  20  20  20

&&

.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.

&&

$$

UPDATE...MROCZKA
AVIATION...RUDE






AREA FORECAST DISCUSSION

NWS COLUMBIA SC

 533 PM EDT SAT OCT 19 2013

.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH THE AREA TONIGHT. MAINLY LIGHT
ISOLATED RAINFALL IS EXPECTED TONIGHT DUE TO THE LIMITED MOISTURE
ASSOCIATED WITH THE FRONT. LOW PRESSURE WILL DEVELOP ON A STALLED
FRONTAL BOUNDARY OFFSHORE BY LATE MONDAY BRINGING ANOTHER CHANCE
FOR RAIN TUESDAY.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
CONVERGENCE ASSOCIATED WITH THE COLD FRONT AND A MID-LEVEL
SHORTWAVE TROUGH WERE HELPING TO SUPPORT SCATTERED SHOWERS.
EXPECT COVERAGE WILL REMAIN SCATTERED BECAUSE OF LIMITED MOISTURE.
THE HRRR KEEPS SHOWERS IN THE EAST PART FOR MUCH OF THE NIGHT.
THE SPC WRF SHOWS ISOLATED SHOWERS EXITING THE EAST PART BY
MIDNIGHT. RADAR TRENDS SUPPORT THE FASTER TIMING. EXPECT FURTHER
DRYING BEHIND THE FRONT OVERNIGHT. THE TEMPERATURE GUIDANCE MAY BE
A LITTLE TOO COOL BECAUSE OF MIXING.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/...
DRY HIGH PRESSURE WILL BRING MORE SEASONABLE CONDITIONS TO THE
REGION. TEMPERATURES SHOULD BE CLOSE TO NORMAL WITH HIGHS IN THE
LOWER TO MIDDLE 70S. LOWS WILL BE BELOW NORMAL SUNDAY
NIGHT...FALLING INTO THE 40S IN MANY LOCATIONS.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
AN UPPER-LEVEL LOW OVER THE GREAT LAKES REGION WILL MOVE
NORTHEAST ACROSS EASTERN CANADA DURING THE EXTENDED PERIOD.
SURFACE HIGH PRESSURE WILL MOVE OFF THE EAST COAST MONDAY NIGHT AS
A COLD FRONT APPROACHES FROM THE WEST. ISENTROPIC LIFT/MOISTURE
FLUX WILL INCREASE FROM THE SOUTH DUE TO A STALLED FRONT ACROSS
THE GULF COAST STATES. ALSO FORCING WILL BE PROVIDED BY UPPER
DIVERGENCE IN THE RIGHT ENTRANCE REGION OF A STRENGTHENING JET.
THESE FACTORS WILL BRING A CHANCE OF SHOWERS TO THE FORECAST AREA
MONDAY NIGHT INTO TUESDAY. THE COLD FRONT WILL CROSS OUR AREA
BY LATE TUESDAY.

COOL AND DRY HIGH PRESSURE WILL RETURN WEDNESDAY THROUGH SATURDAY. EXPECT
BELOW NORMAL TEMPERATURES FOR THE LATTER HALF OF THE WEEK.

&&

.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
VFR CONDITIONS EXPECTED THROUGH THE NEXT 24 HOURS. WEAK FRONTAL
BOUNDARY OFF THE COAST...WITH ANOTHER FRONT STILL WELL WEST OF THE
CWA POISED TO PUSH THROUGH TONIGHT. WEAK UPPER IMPULSES WILL
CONTRIBUTE TO SOME LIGHT SHOWER ACTIVITY OR SPRINKLES ACROSS THE
REGION. SOME LIGHT SHOWERS MAY IMPACT CSRA TAF SITES EARLY IN THE
PERIOD...BUT CONDITIONS WILL STILL BE VFR. LATER TONIGHT...THE
MAIN COLD FRONT WILL PASS THROUGH THE REGION...WITH WINDS BECOMING
MORE NORTHWESTERLY. WITH SOME WINDS FORECAST JUST OFF THE
SURFACE...SHOULD HAVE ENOUGH LOW- LEVEL MIXING TO HELP LIMIT ANY
WIDESPREAD FOG FORMATION.

EXTENDED AVIATION OUTLOOK...NO IMPACTS TO AVIATION EXPECTED THROUGH
MONDAY. A CHANCE OF SHOWERS AND ASSOCIATED RESTRICTIONS TUESDAY.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$







AREA FORECAST DISCUSSION

NWS NORTHERN INDIANA

 152 PM EDT SAT OCT 19 2013

.SYNOPSIS...
ISSUED AT 1114 AM EDT SAT OCT 19 2013

THE RAIN WILL BE ENDING FOR MUCH OF THE REGION TODAY AS AN UPPER
LEVEL TROUGH MOVES THROUGH THE AREA. AREAS NEAR LAKE MICHIGAN
COULD STILL SEE SOME LAKE EFFECT SHOWERS THROUGH THE DAY AS
TEMPERATURES REMAIN COOL. HIGH TEMPERATURES TODAY WILL RANGE FROM
THE UPPER 40S IN THE EAST TO THE LOWER 50S IN THE WEST. TONIGHT
THE LAKE EFFECT RAIN SHOWERS WILL BE ENDING. THERE WILL BE A
CHANCE FOR SOME PATCHY FROST LATE TONIGHT/EARLY IN THE MORNING AS
TEMPERATURES DROP DOWN INTO THE UPPER 30S. THEN TOMORROW THERE
WILL BE MORE SUNSHINE AS TEMPERATURES REACH TO AROUND 60 TO THE
LOWER 60S.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 457 AM EDT SAT OCT 19 2013

SEVERAL FORECAST ISSUES TO CONSIDER FOR THIS PACKAGE...ALL REVOLVING
AROUND PRECIP CHANCES.

UPPER LEVEL TROUGH AXIS WAS LOCATED FROM WESTERN MINNESOTA TO
CENTRAL OKLAHOMA WITH STG WAVE QUICKLY ROUNDING THE BASE AND HEADING
NE TOWARDS THE LOWER GREAT LAKES/OHIO VALLEY. UPWARD MOTION WAS
RAPIDLY INCREASING ACROSS THE REGION IN RESPONSE TO INCREASING MID
LEVEL HGT FALLS APPROACHING 120 M/12 HRS ONCE AGAIN PASS ACROSS THE
AREA. LIGHT RAIN/DRIZZLE HAS BEEN SLOWLY EXPANDING ACROSS CENTRAL
ILLINOIS AND WAS RAPIDLY MOVING/EXPANDING NE INTO MUCH OF THE
FORECAST AREA. AS A RESULT HAVE HAD TO BUMP UP POPS DRAMATICALLY IN
MANY AREAS AND ALSO SPEED ARRIVAL/DEPARTURE TIMES. PERIODS OF
RAIN/SHOWERS WILL LIKELY IMPACT MANY SPOTS GENERALLY SE OF KNOX TO
THREE RIVERS LINE WITH HIGH LIKELY/CAT POPS WARRANTED IN THESE
AREAS. HRRR HAS HANDLED OVERALL EVOLUTION WELL OVER THE PAST SEVERAL
RUNS AND QUICKLY EXITS PRECIP BY 17Z. GRIDS NOW SHOWING THESE TRENDS
WITH QPF ON THE ORDER OF A FEW HUNDREDTHS TO MAYBE NEAR A QUARTER
INCH (SE AREAS) WITH A BRIEF LULL INTO MID AFTERNOON BEFORE FOCUS
SHIFTS TO LAKE EFFECT/ENHANCEMENT.

COLDER AIR WILL SETTLE IN QUICKLY TODAY AND TONIGHT WITH 850 MB
TEMPS DROPPING TO AROUND 0C. THIS COMBINED WITH LAKE SFC TEMPS IN
THE MID TEENS CELSIUS (ROUGHLY 17 C) WILL ALLOW FOR STRONG
INSTABILITY OVER THE LAKE AND POINTS INLAND (LK-H85 DELTA T`S AROUND
17 AND LK-H7 DELTA T`S PUSHING 30 C BY TONIGHT). DESPITE
THIS...AVAILABLE MSTR MAY BE SOMEWHAT LIMITED WITH SOUTHWARD EXTENT
INTO NW PORTIONS OF THE AREA. ALSO TRAJECTORY WILL BE MORE 230 TO
260 MUCH OF THE PERIOD WITH DEEPER CLOUD LAYER MSTR RESIDING ACROSS
N BERRIEN/NW CASS INTO REMAINDER OF WESTERN LWR MI. HAVE MAINTAINED
LIKELY POPS IN THE BERRIEN/CASS CO AREAS WITH QUICK DROP IN POPS
FURTHER EAST AND SOUTH. CHANCES WILL LINGER INTO AT LEAST THIS
EVENING AND POSSIBLY OVERNIGHT. HOWEVER...DELTA T`S WILL BEGIN TO
DECREASE SOMEWHAT AND FLOW LESS FAVORABLE FOR THE AREA FOR
ADDITIONAL PRECIP.

AWAY FROM THE LAKE AREAS...POTENTIAL DOES EXIST FOR SOME PATCHY
FROST IN MAINLY OUTLYING AREAS AS LOWS DIP INTO THE MID 30S IN MANY
AREAS. WINDS MAY REMAIN JUST STRONG ENOUGH TO KEEP FORMATION LIMITED
WITH FROST CONFINED TO HIGHER SURFACES OR FAVORED DRAINAGE AREAS.
FOR NOW WILL LEAVE MENTION OUT OF FORECAST AND DEFER TO DAY SHIFT TO
MONITOR CLEARING TRENDS AND ANTICIPATED WINDS.

&&

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 457 AM EDT SAT OCT 19 2013

SUCCINCT SHARPENING OF MID CANADA/CONUS TROF UNDERWAY WITH CURRENT
SHORTWAVE DIGGING THROUGH WESTERN GREAT LAKES WITH SUBSTANTIVE
BURGEONING BAROCLINIC LEAF SERN MO INTO CENTRAL ILLINOIS. THIS WAVE
TO RAPIDLY TRANSLATE NEWD TO SOUTHEAST ONTARIO BY LATE THIS EVENING.
BUCKLING POSITIVE HEIGHTS SUNDAY AMID PUTRID MOISTURE PROFILES AND
STRONG LOW LEVEL THERMAL PUSH INTO MID MS VLY POINTS TO FINAL DEATH
KNEEL TO PRIOR TOKEN POP MENTION FOR NWRN CWA SUN. A MORE
TIGHTLY PACKED/VIGORED UPSTREAM ENERGY LOBE NOTED IN WV IMAGERY
64N/105W OR JUST NORTH OF MAN/SASK BORDER POISED FOR CROSS
MERIDIONAL FLOW TO DEEPEN WITH MIDLVL SYSTEM DEEPENING INTO WRN
GREAT LAKES SUNDAY NIGHT INTO MONDAY. CONTD SIMILAR THEME WRT POP
COVERAGE LIMITED TO NWRN/NRN CWA IN STRONG LOW LEVEL WAA...WITH BEST
DYNAMICS SHUNTED W-NW-N OF CWA. AND BEST ALBEIT STILL TEMPERED POPS
FOR MONDAY A LA ANAFRONTAL SCENARIO IN TRAILING LOBE OF HEIGHT
FALLS. IT WILL BE THIS SYSTEMS PASSAGE THAT WILL EFFECTIVELY PUT THE
KIBOSH ON THE NOTABLY STRONG/CYCLICAL CAA/WAA LLVL PATTERN
INTERTWIXT BTWN SYSTEMS OF RECENT PAST...AS FINALLY DEEP COLD AIR
BECOMES ENTRENCHED ACROSS GRT LKS REGN. HEREAFTER...STRONG
CONCURRENCE WITH A PRIORI DISCUSSION/GRIDS AS TO INCREASED ACTIVE
LAKE ENHANCED SHRA POTNL WITH 8H/LK THERMAL DIFFERENTIALS INCREASING
TO AROUND 20C. INCREASED CONFIDENCE OF DEEPER COLD PROFILE SUPPORTS
INTRODUCING POTNL FOR LIQUID/FROZEN MIX BY THURSDAY. SOME MINOR
PROBABILISTIC CONCERN FOR FROZEN PTYPE ON WEDNESDAY...THOUGH ONE
PSBL FLY IN THE OINTMENT MAYBE HINTS OF PLAINS TO MID MS VLY CLIPPER
SYSTEM TO DIVE THRU EASTERN PERIPHERY OF BROADLY ARCHED WRN CONUS
RIDGE. THIS SCENARIO SHOULD FAVOR TEMPORARY BACKING CBL
FLOW/INCREASED IN CLOUD SHEAR. THIS ALONG WITH INITIAL WARM SUB
CLOUD REGION...ESPCLY PROXIMAL TO SRN LK MI SHOULD ALLOW FOR
MELT...LENDS TOWARD OMISSION ATTM. GRADUAL THERMAL MODERATION INTO
NEXT WEEKEND AS A TRANSITIONAL PATTERN AND/OR POSSIBLE TEMPORARY
SPLIT FLOW APPEARS FAVORED. DRYING TREND UNTIL GREATER CONFIDENCE OF
NOTEWORTHY SYSTEM POTNL.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 147 PM EDT SAT OCT 19 2013

VFR CONDS XPCD THROUGH THE PD.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 11 AM EDT SUNDAY FOR LMZ043-046.

&&

$$

SYNOPSIS...LOTHAMER
SHORT TERM...FISHER
LONG TERM...MURPHY
AVIATION...T


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AREA FORECAST DISCUSSION

NWS NORTHERN INDIANA

 1127 AM EDT SAT OCT 19 2013

.SYNOPSIS...
ISSUED AT 1114 AM EDT SAT OCT 19 2013

THE RAIN WILL BE ENDING FOR MUCH OF THE REGION TODAY AS AN UPPER
LEVEL TROUGH MOVES THROUGH THE AREA. AREAS NEAR LAKE MICHIGAN
COULD STILL SEE SOME LAKE EFFECT SHOWERS THROUGH THE DAY AS
TEMPERATURES REMAIN COOL. HIGH TEMPERATURES TODAY WILL RANGE FROM
THE UPPER 40S IN THE EAST TO THE LOWER 50S IN THE WEST. TONIGHT
THE LAKE EFFECT RAIN SHOWERS WILL BE ENDING. THERE WILL BE A
CHANCE FOR SOME PATCHY FROST LATE TONIGHT/EARLY IN THE MORNING AS
TEMPERATURES DROP DOWN INTO THE UPPER 30S. THEN TOMORROW THERE
WILL BE MORE SUNSHINE AS TEMPERATURES REACH TO AROUND 60 TO THE
LOWER 60S.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 457 AM EDT SAT OCT 19 2013

SEVERAL FORECAST ISSUES TO CONSIDER FOR THIS PACKAGE...ALL REVOLVING
AROUND PRECIP CHANCES.

UPPER LEVEL TROUGH AXIS WAS LOCATED FROM WESTERN MINNESOTA TO
CENTRAL OKLAHOMA WITH STG WAVE QUICKLY ROUNDING THE BASE AND HEADING
NE TOWARDS THE LOWER GREAT LAKES/OHIO VALLEY. UPWARD MOTION WAS
RAPIDLY INCREASING ACROSS THE REGION IN RESPONSE TO INCREASING MID
LEVEL HGT FALLS APPROACHING 120 M/12 HRS ONCE AGAIN PASS ACROSS THE
AREA. LIGHT RAIN/DRIZZLE HAS BEEN SLOWLY EXPANDING ACROSS CENTRAL
ILLINOIS AND WAS RAPIDLY MOVING/EXPANDING NE INTO MUCH OF THE
FORECAST AREA. AS A RESULT HAVE HAD TO BUMP UP POPS DRAMATICALLY IN
MANY AREAS AND ALSO SPEED ARRIVAL/DEPARTURE TIMES. PERIODS OF
RAIN/SHOWERS WILL LIKELY IMPACT MANY SPOTS GENERALLY SE OF KNOX TO
THREE RIVERS LINE WITH HIGH LIKELY/CAT POPS WARRANTED IN THESE
AREAS. HRRR HAS HANDLED OVERALL EVOLUTION WELL OVER THE PAST SEVERAL
RUNS AND QUICKLY EXITS PRECIP BY 17Z. GRIDS NOW SHOWING THESE TRENDS
WITH QPF ON THE ORDER OF A FEW HUNDREDTHS TO MAYBE NEAR A QUARTER
INCH (SE AREAS) WITH A BRIEF LULL INTO MID AFTERNOON BEFORE FOCUS
SHIFTS TO LAKE EFFECT/ENHANCEMENT.

COLDER AIR WILL SETTLE IN QUICKLY TODAY AND TONIGHT WITH 850 MB
TEMPS DROPPING TO AROUND 0C. THIS COMBINED WITH LAKE SFC TEMPS IN
THE MID TEENS CELSIUS (ROUGHLY 17 C) WILL ALLOW FOR STRONG
INSTABILITY OVER THE LAKE AND POINTS INLAND (LK-H85 DELTA T`S AROUND
17 AND LK-H7 DELTA T`S PUSHING 30 C BY TONIGHT). DESPITE
THIS...AVAILABLE MSTR MAY BE SOMEWHAT LIMITED WITH SOUTHWARD EXTENT
INTO NW PORTIONS OF THE AREA. ALSO TRAJECTORY WILL BE MORE 230 TO
260 MUCH OF THE PERIOD WITH DEEPER CLOUD LAYER MSTR RESIDING ACROSS
N BERRIEN/NW CASS INTO REMAINDER OF WESTERN LWR MI. HAVE MAINTAINED
LIKELY POPS IN THE BERRIEN/CASS CO AREAS WITH QUICK DROP IN POPS
FURTHER EAST AND SOUTH. CHANCES WILL LINGER INTO AT LEAST THIS
EVENING AND POSSIBLY OVERNIGHT. HOWEVER...DELTA T`S WILL BEGIN TO
DECREASE SOMEWHAT AND FLOW LESS FAVORABLE FOR THE AREA FOR
ADDITIONAL PRECIP.

AWAY FROM THE LAKE AREAS...POTENTIAL DOES EXIST FOR SOME PATCHY
FROST IN MAINLY OUTLYING AREAS AS LOWS DIP INTO THE MID 30S IN MANY
AREAS. WINDS MAY REMAIN JUST STRONG ENOUGH TO KEEP FORMATION LIMITED
WITH FROST CONFINED TO HIGHER SURFACES OR FAVORED DRAINAGE AREAS.
FOR NOW WILL LEAVE MENTION OUT OF FORECAST AND DEFER TO DAY SHIFT TO
MONITOR CLEARING TRENDS AND ANTICIPATED WINDS.

&&

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 457 AM EDT SAT OCT 19 2013

SUCCINCT SHARPENING OF MID CANADA/CONUS TROF UNDERWAY WITH CURRENT
SHORTWAVE DIGGING THROUGH WESTERN GREAT LAKES WITH SUBSTANTIVE
BURGEONING BAROCLINIC LEAF SERN MO INTO CENTRAL ILLINOIS. THIS WAVE
TO RAPIDLY TRANSLATE NEWD TO SOUTHEAST ONTARIO BY LATE THIS EVENING.
BUCKLING POSITIVE HEIGHTS SUNDAY AMID PUTRID MOISTURE PROFILES AND
STRONG LOW LEVEL THERMAL PUSH INTO MID MS VLY POINTS TO FINAL DEATH
KNEEL TO PRIOR TOKEN POP MENTION FOR NWRN CWA SUN. A MORE
TIGHTLY PACKED/VIGORED UPSTREAM ENERGY LOBE NOTED IN WV IMAGERY
64N/105W OR JUST NORTH OF MAN/SASK BORDER POISED FOR CROSS
MERIDIONAL FLOW TO DEEPEN WITH MIDLVL SYSTEM DEEPENING INTO WRN
GREAT LAKES SUNDAY NIGHT INTO MONDAY. CONTD SIMILAR THEME WRT POP
COVERAGE LIMITED TO NWRN/NRN CWA IN STRONG LOW LEVEL WAA...WITH BEST
DYNAMICS SHUNTED W-NW-N OF CWA. AND BEST ALBEIT STILL TEMPERED POPS
FOR MONDAY A LA ANAFRONTAL SCENARIO IN TRAILING LOBE OF HEIGHT
FALLS. IT WILL BE THIS SYSTEMS PASSAGE THAT WILL EFFECTIVELY PUT THE
KIBOSH ON THE NOTABLY STRONG/CYCLICAL CAA/WAA LLVL PATTERN
INTERTWIXT BTWN SYSTEMS OF RECENT PAST...AS FINALLY DEEP COLD AIR
BECOMES ENTRENCHED ACROSS GRT LKS REGN. HEREAFTER...STRONG
CONCURRENCE WITH A PRIORI DISCUSSION/GRIDS AS TO INCREASED ACTIVE
LAKE ENHANCED SHRA POTNL WITH 8H/LK THERMAL DIFFERENTIALS INCREASING
TO AROUND 20C. INCREASED CONFIDENCE OF DEEPER COLD PROFILE SUPPORTS
INTRODUCING POTNL FOR LIQUID/FROZEN MIX BY THURSDAY. SOME MINOR
PROBABILISTIC CONCERN FOR FROZEN PTYPE ON WEDNESDAY...THOUGH ONE
PSBL FLY IN THE OINTMENT MAYBE HINTS OF PLAINS TO MID MS VLY CLIPPER
SYSTEM TO DIVE THRU EASTERN PERIPHERY OF BROADLY ARCHED WRN CONUS
RIDGE. THIS SCENARIO SHOULD FAVOR TEMPORARY BACKING CBL
FLOW/INCREASED IN CLOUD SHEAR. THIS ALONG WITH INITIAL WARM SUB
CLOUD REGION...ESPCLY PROXIMAL TO SRN LK MI SHOULD ALLOW FOR
MELT...LENDS TOWARD OMISSION ATTM. GRADUAL THERMAL MODERATION INTO
NEXT WEEKEND AS A TRANSITIONAL PATTERN AND/OR POSSIBLE TEMPORARY
SPLIT FLOW APPEARS FAVORED. DRYING TREND UNTIL GREATER CONFIDENCE OF
NOTEWORTHY SYSTEM POTNL.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 133 AM EDT SAT OCT 19 2013

LIFT AHEAD OF SHORT WAVE MOVING TOWARDS THE REGION HAS ALREADY
ALLOWED FOR LARGE AREA OF VRY LGT RAIN/DRIZZLE TO EXPAND ACROSS MUCH
OF CENTRAL ILLINOIS. GIVEN PRESENT TRAJECTORIES HAVE OPTED TO
INCLUDE VFR MENTION OF LIGHT RAIN AT KSBN FOR A FEW HOURS OVERNIGHT
AND THEN IMPROVING CONDITIONS. WILL MONITOR UPSTREAM TRENDS AS
TROUGH AXIS TO THE WEST MAY SHIFT THROUGH FAST ENOUGH TO PUSH PRECIP
EAST OR LINGER LONG ENOUGH IN THE WEST TO ALLOW FOR MORE EXPANSIVE
LIGHT RAIN. AT KFWA...LONGER PERIOD OF LGT RAIN MAY OCCUR BUT STILL
MINIMAL OVERALL IMPACT WITH EXCURSION INTO MVFR RANGE POSSIBLE
TOWARDS 12Z.

WAVE MOVES AWAY BY EARLY AFTERNOON WITH SW/W FLOW SETTING UP ACROSS
THE LAKES TO ALLOW FOR SOME LAKE ENHANCEMENT CLOUDS/LIGHT SHOWERS.
THIS SHOULD REMAIN GENERALLY NORTH OF KSBN.


&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 11 AM EDT SUNDAY FOR LMZ043-046.

&&

$$

SYNOPSIS...LOTHAMER
SHORT TERM...FISHER
LONG TERM...MURPHY
AVIATION...FISHER


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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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AREA FORECAST DISCUSSION

NWS NORTHERN INDIANA

 459 AM EDT SAT OCT 19 2013

.SYNOPSIS...
ISSUED AT 457 AM EDT SAT OCT 19 2013

AN UPPER LEVEL DISTURBANCE WILL QUICKLY SHIFT ACROSS THE REGION
TODAY...BRINGING A GOOD CHANCE FOR LIGHT RAIN AND SHOWERS TO THE
AREA. BY AFTERNOON...MANY AREAS WILL SEE AN END TO THE
PRECIPITATION WITH MAYBE SOME PEAKS OF SUNSHINE. THE EXCEPTION TO
THIS WILL BE ACROSS MUCH OF LOWER MICHIGAN INTO FAR NW INDIANA
WHERE LAKE EFFECT CLOUD COVER AND SOME SHOWER ACTIVITY IS
EXPECTED. BELOW NORMAL TEMPERATURES WILL PERSIST THROUGH THE NEXT
SEVEN TO 10 DAYS.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 457 AM EDT SAT OCT 19 2013

SEVERAL FORECAST ISSUES TO CONSIDER FOR THIS PACKAGE...ALL REVOLVING
AROUND PRECIP CHANCES.

UPPER LEVEL TROUGH AXIS WAS LOCATED FROM WESTERN MINNESOTA TO
CENTRAL OKLAHOMA WITH STG WAVE QUICKLY ROUNDING THE BASE AND HEADING
NE TOWARDS THE LOWER GREAT LAKES/OHIO VALLEY. UPWARD MOTION WAS
RAPIDLY INCREASING ACROSS THE REGION IN RESPONSE TO INCREASING MID
LEVEL HGT FALLS APPROACHING 120 M/12 HRS ONCE AGAIN PASS ACROSS THE
AREA. LIGHT RAIN/DRIZZLE HAS BEEN SLOWLY EXPANDING ACROSS CENTRAL
ILLINOIS AND WAS RAPIDLY MOVING/EXPANDING NE INTO MUCH OF THE
FORECAST AREA. AS A RESULT HAVE HAD TO BUMP UP POPS DRAMATICALLY IN
MANY AREAS AND ALSO SPEED ARRIVAL/DEPARTURE TIMES. PERIODS OF
RAIN/SHOWERS WILL LIKELY IMPACT MANY SPOTS GENERALLY SE OF KNOX TO
THREE RIVERS LINE WITH HIGH LIKELY/CAT POPS WARRANTED IN THESE
AREAS. HRRR HAS HANDLED OVERALL EVOLUTION WELL OVER THE PAST SEVERAL
RUNS AND QUICKLY EXITS PRECIP BY 17Z. GRIDS NOW SHOWING THESE TRENDS
WITH QPF ON THE ORDER OF A FEW HUNDREDTHS TO MAYBE NEAR A QUARTER
INCH (SE AREAS) WITH A BRIEF LULL INTO MID AFTERNOON BEFORE FOCUS
SHIFTS TO LAKE EFFECT/ENHANCEMENT.

COLDER AIR WILL SETTLE IN QUICKLY TODAY AND TONIGHT WITH 850 MB
TEMPS DROPPING TO AROUND 0C. THIS COMBINED WITH LAKE SFC TEMPS IN
THE MID TEENS CELSIUS (ROUGHLY 17 C) WILL ALLOW FOR STRONG
INSTABILITY OVER THE LAKE AND POINTS INLAND (LK-H85 DELTA T`S AROUND
17 AND LK-H7 DELTA T`S PUSHING 30 C BY TONIGHT). DESPITE
THIS...AVAILABLE MSTR MAY BE SOMEWHAT LIMITED WITH SOUTHWARD EXTENT
INTO NW PORTIONS OF THE AREA. ALSO TRAJECTORY WILL BE MORE 230 TO
260 MUCH OF THE PERIOD WITH DEEPER CLOUD LAYER MSTR RESIDING ACROSS
N BERRIEN/NW CASS INTO REMAINDER OF WESTERN LWR MI. HAVE MAINTAINED
LIKELY POPS IN THE BERRIEN/CASS CO AREAS WITH QUICK DROP IN POPS
FURTHER EAST AND SOUTH. CHANCES WILL LINGER INTO AT LEAST THIS
EVENING AND POSSIBLY OVERNIGHT. HOWEVER...DELTA T`S WILL BEGIN TO
DECREASE SOMEWHAT AND FLOW LESS FAVORABLE FOR THE AREA FOR
ADDITIONAL PRECIP.

AWAY FROM THE LAKE AREAS...POTENTIAL DOES EXIST FOR SOME PATCHY
FROST IN MAINLY OUTLYING AREAS AS LOWS DIP INTO THE MID 30S IN MANY
AREAS. WINDS MAY REMAIN JUST STRONG ENOUGH TO KEEP FORMATION LIMITED
WITH FROST CONFINED TO HIGHER SURFACES OR FAVORED DRAINAGE AREAS.
FOR NOW WILL LEAVE MENTION OUT OF FORECAST AND DEFER TO DAY SHIFT TO
MONITOR CLEARING TRENDS AND ANTICIPATED WINDS.

&&

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 457 AM EDT SAT OCT 19 2013

SUCCINCT SHARPENING OF MID CANADA/CONUS TROF UNDERWAY WITH CURRENT
SHORTWAVE DIGGING THROUGH WESTERN GREAT LAKES WITH SUBSTANTIVE
BURGEONING BAROCLINIC LEAF SERN MO INTO CENTRAL ILLINOIS. THIS WAVE
TO RAPIDLY TRANSLATE NEWD TO SOUTHEAST ONTARIO BY LATE THIS EVENING.
BUCKLING POSITIVE HEIGHTS SUNDAY AMID PUTRID MOISTURE PROFILES AND
STRONG LOW LEVEL THERMAL PUSH INTO MID MS VLY POINTS TO FINAL DEATH
KNEEL TO PRIOR TOKEN POP MENTION FOR NWRN CWA SUN. A MORE
TIGHTLY PACKED/VIGORED UPSTREAM ENERGY LOBE NOTED IN WV IMAGERY
64N/105W OR JUST NORTH OF MAN/SASK BORDER POISED FOR CROSS
MERIDIONAL FLOW TO DEEPEN WITH MIDLVL SYSTEM DEEPENING INTO WRN
GREAT LAKES SUNDAY NIGHT INTO MONDAY. CONTD SIMILAR THEME WRT POP
COVERAGE LIMITED TO NWRN/NRN CWA IN STRONG LOW LEVEL WAA...WITH BEST
DYNAMICS SHUNTED W-NW-N OF CWA. AND BEST ALBEIT STILL TEMPERED POPS
FOR MONDAY A LA ANAFRONTAL SCENARIO IN TRAILING LOBE OF HEIGHT
FALLS. IT WILL BE THIS SYSTEMS PASSAGE THAT WILL EFFECTIVELY PUT THE
KIBOSH ON THE NOTABLY STRONG/CYCLICAL CAA/WAA LLVL PATTERN
INTERTWIXT BTWN SYSTEMS OF RECENT PAST...AS FINALLY DEEP COLD AIR
BECOMES ENTRENCHED ACROSS GRT LKS REGN. HEREAFTER...STRONG
CONCURRENCE WITH A PRIORI DISCUSSION/GRIDS AS TO INCREASED ACTIVE
LAKE ENHANCED SHRA POTNL WITH 8H/LK THERMAL DIFFERENTIALS INCREASING
TO AROUND 20C. INCREASED CONFIDENCE OF DEEPER COLD PROFILE SUPPORTS
INTRODUCING POTNL FOR LIQUID/FROZEN MIX BY THURSDAY. SOME MINOR
PROBABILISTIC CONCERN FOR FROZEN PTYPE ON WEDNESDAY...THOUGH ONE
PSBL FLY IN THE OINTMENT MAYBE HINTS OF PLAINS TO MID MS VLY CLIPPER
SYSTEM TO DIVE THRU EASTERN PERIPHERY OF BROADLY ARCHED WRN CONUS
RIDGE. THIS SCENARIO SHOULD FAVOR TEMPORARY BACKING CBL
FLOW/INCREASED IN CLOUD SHEAR. THIS ALONG WITH INITIAL WARM SUB
CLOUD REGION...ESPCLY PROXIMAL TO SRN LK MI SHOULD ALLOW FOR
MELT...LENDS TOWARD OMISSION ATTM. GRADUAL THERMAL MODERATION INTO
NEXT WEEKEND AS A TRANSITIONAL PATTERN AND/OR POSSIBLE TEMPORARY
SPLIT FLOW APPEARS FAVORED. DRYING TREND UNTIL GREATER CONFIDENCE OF
NOTEWORTHY SYSTEM POTNL.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 133 AM EDT SAT OCT 19 2013

LIFT AHEAD OF SHORT WAVE MOVING TOWARDS THE REGION HAS ALREADY
ALLOWED FOR LARGE AREA OF VRY LGT RAIN/DRIZZLE TO EXPAND ACROSS MUCH
OF CENTRAL ILLINOIS. GIVEN PRESENT TRAJECTORIES HAVE OPTED TO
INCLUDE VFR MENTION OF LIGHT RAIN AT KSBN FOR A FEW HOURS OVERNIGHT
AND THEN IMPROVING CONDITIONS. WILL MONITOR UPSTREAM TRENDS AS
TROUGH AXIS TO THE WEST MAY SHIFT THROUGH FAST ENOUGH TO PUSH PRECIP
EAST OR LINGER LONG ENOUGH IN THE WEST TO ALLOW FOR MORE EXPANSIVE
LIGHT RAIN. AT KFWA...LONGER PERIOD OF LGT RAIN MAY OCCUR BUT STILL
MINIMAL OVERALL IMPACT WITH EXCURSION INTO MVFR RANGE POSSIBLE
TOWARDS 12Z.

WAVE MOVES AWAY BY EARLY AFTERNOON WITH SW/W FLOW SETTING UP ACROSS
THE LAKES TO ALLOW FOR SOME LAKE ENHANCEMENT CLOUDS/LIGHT SHOWERS.
THIS SHOULD REMAIN GENERALLY NORTH OF KSBN.


&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 11 AM EDT SUNDAY FOR LMZ043-046.

&&

$$

SYNOPSIS...FISHER
SHORT TERM...FISHER
LONG TERM...MURPHY
AVIATION...FISHER


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AREA FORECAST DISCUSSION

NWS DES MOINES IA

 1148 PM CDT FRI OCT 18 2013

.SHORT TERM /TONIGHT/...
ISSUED AT 323 PM CDT FRI OCT 18 2013

IN A NEAR REPEAT OF YESTERDAY AFTERNOONS FORECAST...ANOTHER 500 MB
SHORTWAVE EMBEDDED IN THE MEAN CENTRAL NORTH AMERICAN LONGWAVE
TROUGH IS POISED TO TRACK THROUGH IOWA LATE TONIGHT AND INTO
TOMORROW MORNING. AS WITH ITS PREDECESSOR...FORCING AND MOISTURE
WILL BE SPARSE AND ANY RAIN SHOWERS OVERNIGHT WILL BE CONFINED TO
NORTHERN IOWA. THIS SCENARIO WAS HANDLED WELL BY THE HIGH RES WRF
ARW AND RAP...THUS USED A BLEND OF THESE TWO MODELS FOR THE
PRECIPITATION FORECAST. A SECOND IMPULSE/VORT MAX SLIDES DOWN THE
REAR FLANK OF THE LONGWAVE TROUGH IN WESTERN MINNESOTA AND NORTHWEST
IOWA TOWARDS THE END OF THE PERIOD. MOISTURE PROFILES ARE SLIGHTLY
MORE CONDUCIVE FOR RAINFALL AND HAVE INCREASED POPS ACCORDINGLY IN
THE NORTHWEST TOWARDS 12Z SAT.

290 TO 300K ISENTROPIC ACCENT GENERATED A BAND RAIN AND SNOW ACROSS
KANSAS AND NORTHERN MISSOURI TODAY. THE ASSOCIATED SHIELD OF
CIRROSTRATUS AND ALTOSTRATUS CLOUDS PROPAGATED INTO IOWA THIS
MORNING AND PUT A DAMPER ON HIGHS ACROSS THE SOUTHERN HALF OF THE
CWA. THIS SYSTEM WILL PULL ENE THIS EVENING AS THE UPPER LEVEL
TROUGH DIGS INTO THE CENTRAL PLAINS. THERE IS SOME UNCERTAINTY WITH
HOW MUCH OF THE CLOUD COVER OVER SOUTHERN IOWA WILL CLEAR OUT
BETWEEN THE 06 AND 12Z TIME FRAME. BOTH THE NAM AND RAP SOUNDINGS
HINT AT SOME CLEARING TOWARDS MORNING...SO LOWERED MIN TEMPS IN THE
NISH VALLEY AND OTHER PORTIONS OF SOUTHWEST IOWA.

.LONG TERM /SATURDAY THROUGH FRIDAY/...
ISSUED AT 323 PM CDT FRI OCT 18 2013

BROAD LONG WAVE TROF WILL REMAIN ENTRENCHED ACROSS THE EASTERN
HALF OF THE UNITED STATES DURING THIS FORECAST PERIOD.
THEREFORE...BELOW NORMAL TEMPERATURES ARE EXPECTED FOR MUCH OF THE
NEXT WEEK. THERE WILL ALSO BE THREATS FOR LIGHT PRECIPITATION FROM
TIME TO TIME AS SYSTEMS PASS THROUGH THE STRONG NORTHWEST FLOW.
FIRST WEAK SYSTEM GLANCES THE NORTH TOMORROW MORNING ALTHOUGH THE
BULK OF THE FORCING WILL REMAIN NORTH OF IOWA. HAVE CONTINUED THE
THREAT FOR SOME ISOLATED/SCATTERED SHOWERS IN THE MORNING BUT WITH
SUBSIDENCE ARRIVING BY AFTERNOON...SHOULD SEE ANY ACTIVITY QUICKLY
ENDING. WARM ADVECTION INTO SUNDAY WILL MAKE IT THE WARMEST DAY
OVER THE NEXT WEEK. THE WARMER AIR IS AHEAD OF THE NEXT SYSTEM
DIVING SOUTHEAST INTO THE REGION. ONCE AGAIN...THE FORCING
ASSOCIATED WITH THIS SYSTEM REMAINS NORTH OF IOWA WITH ANY PCPN
THREAT RESIDING NEAR THE MINNESOTA BORDER. STRONG COLD ADVECTION
WILL ARRIVE BY LATE IN THE DAY WITH A MUCH COLDER AIRMASS BECOMING
ESTABLISHED ACROSS THE STATE ON MONDAY. ONE FINAL SYSTEM DROPS
SOUTHEAST TOWARD THE STATE LATE MONDAY NIGHT INTO TUESDAY. THE
EURO IS MOST AGGRESSIVE WITH SATURATION AND LIFT ACROSS IOWA WITH
A FEW TENTHS OF PCPN ON TUESDAY. GIVEN RELATIVELY COLD THERMAL
PROFILES DURING THIS EVENT...WOULDNT BE SURPRISED TO SEE SOME SNOW
MIXED WITH RAIN WITH STRONG DYNAMICAL COOLING SUGGESTED BY THE
LIFT. THE COLDER AIRMASS WILL THEN REMAIN ESSENTIALLY IN PLACE
THROUGH THE END OF NEXT WEEK. THIS SHOULD EFFECTIVELY END THE
GROWING SEASON ACROSS CENTRAL IOWA FOR THOSE LOCATIONS THAT HAVENT
ALREADY SEEN A FREEZE.

&&

.AVIATION...19/06Z
ISSUED AT 1148 PM CDT FRI OCT 18 2013

VFR CONDITIONS EXPECTED TO MAINTAIN THROUGH 12Z. A FEW SHOWERS AND
AREAS OF MVFR CIGS ARE POSSIBLE OVER THE NORTH AND NORTHEAST
SATURDAY MORNING INTO THE EARLY AFTERNOON. THE CIGS WILL GRADUALLY
RISE AND BE PRIMARILY VFR BY THE AFTERNOON. THE WIND WILL BECOME
BREEZY FROM THE WEST DURING THE DAY BEFORE DIMINISHING BY THE
EVENING.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...SKOW
LONG TERM...COGIL
AVIATION...DONAVON







AREA FORECAST DISCUSSION

NWS PITTSBURGH PA

 854 PM EDT SUN OCT 20 2013

.SYNOPSIS...
THE LAST WARM DAY FOR A WHILE OCCURS MONDAY WHEN TEMPERATURES
CLIMB INTO THE 60S. A COLD FRONT PASSES MONDAY NIGHT INTO TUESDAY
DRIVING TEMPERATURES 10 TO 15 DEGREES BELOW NORMAL THE REMAINDER
OF THE WEEK. WINTER TYPE PRECIPITATION IS POSSIBLE AS WE HEAD
TOWARD WEEKS END.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
ATMOSPHERE REMAINS CLOUD FREE THIS EVENING AS WARM ADVECTION EATS
AWAY AT THE SOUTHERN PERIPHERY OF CLOUDS. NAM12 AND RUC13 H5-H3 MSTR
PROFILES KEEP 70% RH OUT OF FCST AREA UNTIL THE 9-12Z WINDOW. AS
A RESULT ADJUSTED SKY GRIDS TO CLR FOR THE I-80 CORRIDOR OVERNIGHT
AND TWEAKED TEMPS DOWNWARD A FEW DEGREES. 24 HR DELTAS FOR T AND
TD ARE 5-7F COMBINED WITH WIND STILL 5-8KTS FROST WILL BE
ISOLATED IN DEEPER VALLEYS AND HOLLOWS OF NRN WV WHERE GROWING
SEASON REMAINS.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/...
WARM ADVCTN ON THE ERN FLANK OF GREAT LAKES LOW PRES WL CONT THROUGH
MONDAY WITH THE AFOREMENTIONED INVERSION QUICKLY MIXING OUT FOR A
RAPID TEMP RISE.  USED THE WARMER GFSMOS AS A BASE FOR MONDAY HIGHS.

AN ADVNG SHRTWV IN SW FLOW ALOFT IS FORECAST TO SPREAD RAIN OVR
THAT SYSTEMS BAROCLINIC ZONE/CDFNTAL REGION...WHICH IS PROGGED ACRS
CNTRL OH BY MONDAY EVE. RAIN IS EXPECTED TO CONTINUE AS THE ZONE
IS SHUNTED EWD MONDAY NGT AND TUESDAY. CHC TO LIKELY POPS WERE
THUS MAINTAINED WITH TIMING ADJUSTMENTS BASED ON THE LATEST
DETERMINISTIC TRENDS...BUT POPS SHOULD DIMINISH RAPIDLY ON TUESDAY
AS THE SPPRTG SHRTWV TRANSLATES RAPIDLY NEWD.

TEMPS IN THE WAKE OF THE SFC FRONT WL BE FALLING DRAMATICALLY THOUGH
WITH TUESDAY HIGHS FORECAST ABOUT 15 DEGREES UNDR THE MONDAY MAXIMUMS.

THE NXT IN SERIES OF DISTURBANCES IS FORECAST THROUGH THE BASE OF
THE EWD SHIFTING UPR TROFS EARLY ON WED. TIMING OF THAT SHRTWV HAS
NOT BEEN CONSISTENT AND NAM SENDS THE CNTRL VORT MAX SOUTH OF THE
AREA. POP CHANGES WERE THUS STRETCHED TO ACCOMMODATE TIMING AND
COLLABORATION ISSUES. IN GENL...CHC TO LOW END LIKELY NMBRS WERE
INCLUDED WITH EXPECTATIONS OF LGT...BUT COLD SHOWERS WITH SOME
SNOW FLAKES OR SLEET MIXED IN.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
MDLS HAVE BEEN CONSISTENT THOUGH IN PROGS OF UPR TROF DVLPMNT OVR ERN
NORTH AMERICA WITH RESULTANT COLD FLOW ACRS RELATIVELY WARM LAKES
DURING THE LATTER HALF OF THE WEEK. PROBLEM WILL BE OF SHRTWV
TIMING...THERMAL TROFS OF WHICH MAY BE NEEDED TO SUFFICIENTLY
DEEPEN MIXING LVLS FOR FOR LAKE AND RIDGE ENHANCED SNOW SHWRS.

COLD TEMPS WERE THUS ADJUSTED...BUT HAVE GENLY PERSISTED WITH
PREVIOUS POPS AS CONFIDNENCE HAS WANED IN TIMING...OVRALL COLUMN
TEMPS...AND MIXING LYR WND DIRECTIONS.

&&

.AVIATION /01Z MONDAY THROUGH FRIDAY/...
JUST A FEW CONVECTIVE CLOUDS LEFT ALONG THE NORTHERN PERIPHERY OF
THE AREA...BASICALLY ONLY CLIPPING AREAS NORTH OF KFKL AND KDUJ.
CLEAR SKIES AND GENERALLY LIGHT SOUTHWEST WINDS WILL CONTINUE
UNTIL HIGHER MOMENTUM MIXES DOWN ON MONDAY. SOME GUSTS ARE
POSSIBLE THROUGH THE AFTERNOON AND HIGH THEN MID CLOUDS STAR TO
BUILD INTO THE AREA FROM WEST TO EAST AHEAD OF THE NEXT SYSTEM.
FRIES

OUTLOOK.../MONDAY NIGHT THROUGH FRIDAY/...
RSTRNS ARE LIKELY IN SHWRS WITH A MON NGT/TUE CDFNT. MORE RSTRNS
ARE PSBL IN RA/SN SHWRS THRU ERLY FRI AS UPR LVL DISTURBANCES
CROSS THE GT LKS AND OH VLY RGN.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

SYNOPSIS...98
NEAR TERM...98
SHORT TERM...15
LONG TERM...07
AVIATION...FRIES





AREA FORECAST DISCUSSION

NWS WAKEFIELD VA

 500 PM EDT SAT OCT 19 2013

.SYNOPSIS...
A COLD FRONT CROSSES THE REGION AND MOVES OFF THE COAST OVERNIGHT.
HIGH PRESSURE SETTLES OVER THE MID ATLANTIC STATES SUNDAY AND
MOVES OFF THE COAST MONDAY. ANOTHER COLD FRONT WILL MOVE THROUGH
WEDNESDAY.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
UPPER LEVEL ANALYSIS HAS A LONG WAVE TROUGH FROM CENTRAL CANADA
SOUTH THROUGH THE MISSISSIPPI VALLEY. SOUTHERN JET STREAM FROM
LOUISIANA TO THE MID ATLANTIC COAST WAS BRINGING MID LEVEL MOISTURE
ACROSS THE CWA. A COLD FRONT EXTENDED FROM LOW PRESSURE OVER THE
NORTHERN GREAT LAKES SOUTH THROUGH EASTERN OHIO AND INTO
MISSISSIPPI. A STATIONARY FRONT EXTENDED ALONG THE CAROLINA COAST
SOUTHWEST INTO THE GULF OF MEXICO.

THE MID LEVEL MOISTURE IN COMBINATION WITH A WEAK SURFACE/LOW LEVEL
TROUGH OVER EASTERN WV WAS RESULTING IN SCATTERED VERY LIGHT SHOWERS
ACROSS MUCH OF THE CWA. MODELS HAVE HANDLED THIS ACTIVITY RATHER
POORLY BUT THE RUC SEEMS TO HAVE THE BEST HANDLE ON IT CURRENTLY.
STARTING THE FORECAST THROUGH 00Z WITH AT LEAST 30 PERCENT POPS.
PCPN AMOUNTS WILL CONTINUE TO BE QUITE LIGHT...GENERALLY A FEW
HUNDREDTHS OF AN INCH AT THE MOST. DRIER AIR WILL GRADUALLY FILTER
IN FROM THE SW WITH A CHC FOR PCPN CONTINUING OVER NORTHERN PORTIONS
TIL 04Z AHEAD OF THE COLD FRONT.

THE COLD FRONT WILL BEGIN TO PASS THROUGH SHORTLY AFTER MIDNIGHT AND
REACH THE COAST BY AROUND 4 AM EDT. THIS WILL BRING SHARP CLEARING
AND SWEEP MUCH OF THE MOISTURE OFF TO THE EAST.

KEPT HOURLY TEMPERATURES ELEVATED THIS EVENING FROM A NORMAL DIURNAL
CURVE THEN LOWERED THEM MORE QUICKLY FOLLOWING THE FRONTAL PASSAGE.
MAINLY USED THE SREF FOR LOW TEMPERATURES SUNDAY MORNING WHICH
VERIFIED WELL FRIDAY MORNING. LOWS ARE FORECAST TO RANGE FROM THE
LWR 40S ACROSS THE PIEDMONT TO MID AND UPR 50S IN THE SE.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
SFC HIGH PRESSURE PERSISTS THROUGH SUNDAY/SUNDAY NIGHT AND SLIDES
OFFSHORE ON MONDAY. A MOSTLY CLEAR SKY AND COOL TEMPERATURES WILL
PERSIST. WITH HIGH PRESSURE OVER THE AREA SUNDAY...SUBSIDENCE WILL
HOLD TEMPERATURES DOWN FROM THEIR POTENTIAL. HIGHS ARE FORECAST TO
RANGE FROM AROUND 60 IN THE NORTHERN NECK AND THE MD EASTERN SHORE
TO THE MID 60S ALONG THE NC BORDER.

IDEAL RADIATIONAL COOLING WILL THEN BRING THE COOLEST NIGHT SO FAR
THIS SEASON. LOWS MONDAY MORNING RANGE FROM THE UPR 30S WELL INLAND
TO THE MID 40S AT THE COAST.

AS HIGH PRESSURE SLIDES OFF THE COAST...TEMPERATURES WARM A BIT
MONDAY WITH HIGHS IN THE MID TO UPR 60S. WITH THE SOUTHERLY WINDS
AND AN INCREASE IN CLOUDINESS...LOW TEMPERATURES WILL BE MILDER
TUESDAY MORNING...RANGING FROM THE MID 40S INLAND TO THE MID 50S
NEAR THE COAST.

DUE TO LOW PRESSURE DEVELOPMENT ON THE FRONT OFF THE CAROLINA
COAST...THERE IS A SLIGHT TO LOW CHC FOR RAIN OVER SE PORTIONS.
THERE IS UNCERTAINTY AS TO WHETHER THIS WILL EVEN MAKE IT INTO OUR
AREA. FOR NOW HAVE A 30 PERCENT CHANCE FOR SHOWERS NEAR THE
ALBEMARLE SOUND WITH 20 PERCENT POPS INTO SOUTHEAST VIRGINIA. HIGH
TEMPERATURES ACROSS THE AREA ON TUESDAY RANGE FROM 65 TO 70.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
WILL LEAN TOWARD THE 12Z ECMWF MODEL FOR THE EXTENDED PERIOD.
ANOTHER SRN STREAM WEAK LO PRES AREA WILL MOVE OFF THE SE AND MID
ATLC CST LATE TUE INTO WED MORNG...FOLLOWED BY A COLD FRONT
PUSHING OFF THE CST BY WED EVENG. THIS SCENARIO WILL PROVIDE A
SLGT CHC OR SML CHC FOR SHOWERS ACRS THE AREA. THEN...A VERY
DRY/COOL AIRMASS WILL DOMINATE THE REGION WED NGT THRU SAT...AS HI
PRES WILL BLD TWD AND INTO THE AREA FM THE W. MIN TEMPS WILL RANGE
FM THE LWR 40S TO LWR 50S WED MORNG...IN THE UPR 30S TO MID 40S
THU MORNG...AND MAINLY IN THE MID 30S TO LWR 40S FRI AND SAT
MORNGS. MAX TEMPS WILL MAINLY RANGE FM THE UPR 50S TO MID 60S THRU
THE PERIOD.

&&

.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
MOISTURE FROM DEPARTING LOW PRESSURE OFF THE MID ATLANTIC COAST
AND AHEAD OF APPROACHING COLD FRONT HAS RESULTED IN SPORATIC IFR
CIGS PAST FEW HOURS ALONG WITH AREAS OF LIGHT RAIN. EXPECT THESE
CONDITIONS TO CONTINUE FOR THE NEXT 3-6 HRS BEFORE WINDS TURN MORE
SW AHEAD OF THE FRONT THIS EVENING. THIS SHOULD SCOUR OUT THE ST
LEAVING BKN SC BETWEEN 2-4K FT UNTIL FROPA. EXPECT DECREASING
CLOUDINESS ALONG WITH A WIND SHIFT TO THE N LATE TONITE.

OUTLOOK...VFR CONDITIONS EXPECTED SUN AND MON AS HIGH PRESSURE
BUILDS INTO THE AREA. ANOTHER WEAK SYSTEM PASSES OFF THE NC COAST
TUE AND COULD BRING CIGS DOWN TO 3K FT OR LESS AT KECG/KORF.

&&

.MARINE...
WILL MAINTAIN SCA HEADLINES FOR ALL ZNS EXCEPT SRN TWO CSTL WTRS.
A COLD FRONT WILL PUSH OFF THE CST TNGT...AS HI PRES BLDS IN FM
THE W. SSW WINDS LESS THAN 15 KT WILL SHIFT TO THE NW LATE TNGT
AND INCREASE TO 15 TO 25 KT...WITH GUSTS TO AROUND 30 KT BY SUN
MORNG. THIS NW OR N SURGE WILL LAST THRU SUN MORNG...THEN DIMINISH
RATHER QUICKLY SUN AFTN...AS SFC HI PRES BLDS RIGHT OVR THE AREA.
FAIRLY QUIET SUN NGT INTO TUE...AS FCST AREA WILL BE BETWEEN
ANOTHER SFC LO WELL TO THE S AND ANOTHER LO PRES SYSTEM MOVING
ACRS THE GRT LKS. A STRONG COLD FRONT WILL EVENTUALLY PUSH THRU
LATE WED/WED NGT...BRINGING ANOTHER ROUND OF SCA OR POSSIBLY EVEN
GALE CONDITIONS.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM TO NOON EDT SUNDAY FOR
     ANZ632>638-650-652-654.
     SMALL CRAFT ADVISORY FROM 1 AM TO NOON EDT SUNDAY FOR ANZ630-
     631.

&&

$$
SYNOPSIS...LSA
NEAR TERM...LSA
SHORT TERM...LSA
LONG TERM...TMG
AVIATION...MPR
MARINE...TMG







AREA FORECAST DISCUSSION

NWS WAKEFIELD VA

 349 PM EDT SAT OCT 19 2013

.SYNOPSIS...
A COLD FRONT CROSSES THE REGION AND MOVES OFF THE COAST OVERNIGHT.
HIGH PRESSURE SETTLES OVER THE MID ATLANTIC STATES SUNDAY AND
MOVES OFF THE COAST MONDAY. ANOTHER COLD FRONT WILL MOVE THROUGH
WEDNESDAY.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
UPPER LEVEL ANALYSIS HAS A LONG WAVE TROUGH FROM CENTRAL CANADA
SOUTH THROUGH THE MISSISSIPPI VALLEY. SOUTHERN JET STREAM FROM
LOUISIANA TO THE MID ATLANTIC COAST WAS BRINGING MID LEVEL MOISTURE
ACROSS THE CWA. A COLD FRONT EXTENDED FROM LOW PRESSURE OVER THE
NORTHERN GREAT LAKES SOUTH THROUGH EASTERN OHIO AND INTO
MISSISSIPPI. A STATIONARY FRONT EXTENDED ALONG THE CAROLINA COAST
SOUTHWEST INTO THE GULF OF MEXICO.

THE MID LEVEL MOISTURE IN COMBINATION WITH A WEAK SURFACE/LOW LEVEL
TROUGH OVER EASTERN WV WAS RESULTING IN SCATTERED VERY LIGHT SHOWERS
ACROSS MUCH OF THE CWA. MODELS HAVE HANDLED THIS ACTIVITY RATHER
POORLY BUT THE RUC SEEMS TO HAVE THE BEST HANDLE ON IT CURRENTLY.
STARTING THE FORECAST THROUGH 00Z WITH AT LEAST 30 PERCENT POPS.
PCPN AMOUNTS WILL CONTINUE TO BE QUITE LIGHT...GENERALLY A FEW
HUNDREDTHS OF AN INCH AT THE MOST. DRIER AIR WILL GRADUALLY FILTER
IN FROM THE SW WITH A CHC FOR PCPN CONTINUING OVER NORTHERN PORTIONS
TIL 04Z AHEAD OF THE COLD FRONT.

THE COLD FRONT WILL BEGIN TO PASS THROUGH SHORTLY AFTER MIDNIGHT AND
REACH THE COAST BY AROUND 4 AM EDT. THIS WILL BRING SHARP CLEARING
AND SWEEP MUCH OF THE MOISTURE OFF TO THE EAST.

KEPT HOURLY TEMPERATURES ELEVATED THIS EVENING FROM A NORMAL DIURNAL
CURVE THEN LOWERED THEM MORE QUICKLY FOLLOWING THE FRONTAL PASSAGE.
MAINLY USED THE SREF FOR LOW TEMPERATURES SUNDAY MORNING WHICH
VERIFIED WELL FRIDAY MORNING. LOWS ARE FORECAST TO RANGE FROM THE
LWR 40S ACROSS THE PIEDMONT TO MID AND UPR 50S IN THE SE.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
SFC HIGH PRESSURE PERSISTS THROUGH SUNDAY/SUNDAY NIGHT AND SLIDES
OFFSHORE ON MONDAY. A MOSTLY CLEAR SKY AND COOL TEMPERATURES WILL
PERSIST. WITH HIGH PRESSURE OVER THE AREA SUNDAY...SUBSIDENCE WILL
HOLD TEMPERATURES DOWN FROM THEIR POTENTIAL. HIGHS ARE FORECAST TO
RANGE FROM AROUND 60 IN THE NORTHERN NECK AND THE MD EASTERN SHORE
TO THE MID 60S ALONG THE NC BORDER.

IDEAL RADIATIONAL COOLING WILL THEN BRING THE COOLEST NIGHT SO FAR
THIS SEASON. LOWS MONDAY MORNING RANGE FROM THE UPR 30S WELL INLAND
TO THE MID 40S AT THE COAST.

AS HIGH PRESSURE SLIDES OFF THE COAST...TEMPERATURES WARM A BIT
MONDAY WITH HIGHS IN THE MID TO UPR 60S. WITH THE SOUTHERLY WINDS
AND AN INCREASE IN CLOUDINESS...LOW TEMPERATURES WILL BE MILDER
TUESDAY MORNING...RANGING FROM THE MID 40S INLAND TO THE MID 50S
NEAR THE COAST.

DUE TO LOW PRESSURE DEVELOPMENT ON THE FRONT OFF THE CAROLINA
COAST...THERE IS A SLIGHT TO LOW CHC FOR RAIN OVER SE PORTIONS.
THERE IS UNCERTAINTY AS TO WHETHER THIS WILL EVEN MAKE IT INTO OUR
AREA. FOR NOW HAVE A 30 PERCENT CHANCE FOR SHOWERS NEAR THE
ALBEMARLE SOUND WITH 20 PERCENT POPS INTO SOUTHEAST VIRGINIA. HIGH
TEMPERATURES ACROSS THE AREA ON TUESDAY RANGE FROM 65 TO 70.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
WILL BE UPDATED SHORTLY

&&

.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
MOISTURE FROM DEPARTING LOW PRESSURE OFF THE MID ATLANTIC COAST
AND AHEAD OF APPROACHING COLD FRONT HAS RESULTED IN SPORATIC IFR
CIGS PAST FEW HOURS ALONG WITH AREAS OF LIGHT RAIN. EXPECT THESE
CONDITIONS TO CONTINUE FOR THE NEXT 3-6 HRS BEFORE WINDS TURN MORE
SW AHEAD OF THE FRONT THIS EVENING. THIS SHOULD SCOUR OUT THE ST
LEAVING BKN SC BETWEEN 2-4K FT UNTIL FROPA. EXPECT DECREASING
CLOUDINESS ALONG WITH A WIND SHIFT TO THE N LATE TONITE.

OUTLOOK...VFR CONDITIONS EXPECTED SUN AND MON AS HIGH PRESSURE
BUILDS INTO THE AREA. ANOTHER WEAK SYSTEM PASSES OFF THE NC COAST
TUE AND COULD BRING CIGS DOWN TO 3K FT OR LESS AT KECG/KORF.

&&

.MARINE...
NO CHANGE TO SCA HEADLINES. DISCUSSION WILL FOLLOW SHORTLHY.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM TO NOON EDT SUNDAY FOR
     ANZ632>638-650-652-654.
     SMALL CRAFT ADVISORY FROM 1 AM TO NOON EDT SUNDAY FOR ANZ630-
     631.

&&

$$
SYNOPSIS...LSA
NEAR TERM...LSA
SHORT TERM...LSA
LONG TERM...TMG
AVIATION...MPR
MARINE...TMG







AREA FORECAST DISCUSSION

NWS GAYLORD MI

 200 PM EDT SAT OCT 19 2013

.SYNOPSIS...
ISSUED AT 233 AM EDT SAT OCT 19 2013

AN ACTIVE AND CHILLY PATTERN WILL REMAIN ACROSS THE GREAT LAKES
RIGHT THROUGH NEXT WEEK. THE MOST SIGNIFICANT LOW PRESSURE SYSTEM IN
THE NEAR FUTURE WILL MOVE SOUTHEAST FROM CENTRAL CANADA THIS
WEEKEND...REACHING LAKE SUPERIOR BY MONDAY MORNING. THE COLDEST AIR
OF THE FALL SEASON SO FAR WILL ENTER THE REGION BEHIND THE LOW
PRESSURE SYSTEM. TEMPERATURES MAY GET COLD ENOUGH NEXT WEEK TO BRING
THE FIRST SNOWFALL OF THE SEASON...ESPECIALLY TO THE INTERIOR
HIGHLANDS OF NORTHERN LOWER MICHIGAN.

&&

.UPDATE...
ISSUED AT 200 PM EDT SAT OCT 19 2013

SYNOPTIC "WRAP AROUND" PRECIP EXITING INTO LAKE HURON.
BUT...CONVECTIVE SHOWERS HAVE ALREADY DEVELOPED OVER NW LOWER
MICHIGAN AND PARTS OF EASTERN UPPER MICHIGAN...WITHIN LAKE
MICHIGAN AND SUPERIOR "HEAT PLUMES" PUSHING INLAND...AND STEEP
LOW-MID LEVEL LAPSE RATES. HEAVIER SHOWERS ARE PRODUCING SMALL
HAIL...WITNESSED AT THIS OFFICE ABOUT AN HOUR AGO.

REST OF THE AFTERNOON...EXPECT MORE OF THE SAME. CORE OF MID
LEVEL COLD AIR (-30C TO -32C) WILL SLIDE INTO THE REGION LATE THIS
AFTERNOON AND THIS EVENING. DAYTIME AND LAKE HEATING DOWN LOW
SHOULD KEEP SHOWERS GOING THROUGH THE AFTERNOON PARTICULARLY ACROSS
EASTERN UPPER AND NORTHWEST LOWER MICHIGAN WITH FLOW OFF THE
LAKES. SMALL HAIL AND SOME THUNDER ALSO POSSIBLE WITH A FEW
HUNDRED JOULES OF CAPE AND EQUILIBRIUM LEVELS POKING ABOVE -20C.

UPDATE ISSUED AT 1111 AM EDT SAT OCT 19 2013

SHARP SHORT WAVE TROUGH AND FIRST ROUND OF COLDER AIR NOW SWINGING
THROUGH THE WESTERN GREAT LAKES. ASSOCIATED JET CORE AXIS RUNS
NORTHEASTWARD UP THROUGH THE OHIO VALLEY AND ACROSS FAR SE LOWER
MICHIGAN. LEFT EXIT REGION FORCING HELPING TO DEEPEN LOW PRESSURE
OVER NRN LAKE HURON WITH A TRAILING COLD FRONT/SFC TROUGH AXIS
STRETCHING BACK THROUGH NE LOWER MICHIGAN INTO CENTRAL LOWER
MICHIGAN. BATCH OF FAIRLY WIDESPREAD "WRAP AROUND" RAINFALL
MOVING ACROSS NE LOWER MICHIGAN THIS LATE THIS MORNING RIGHT
BEHIND THE FRONT.

FURTHER WEST...WELL DEFINED DRY SLOT/CLEARING LINE POKING UP INTO
THE WESTERN GREAT LAKES AND NOSING INTO EASTERN UPPER/NW LOWER
MICHIGAN.

REST OF TODAY...PER SATELLITE TRENDS...CLEARING LINE WILL WORK ITS
WAY EASTWARD OVER THE NEXT FEW HOURS AS LOW AMPLITUDE LOW-MID
LEVEL RIDGING SLIDES THROUGH THE REGION. THIS WILL BRING VARYING
DEGREES OF SUNSHINE TO THE CWA...AT LEAST FOR A BRIEF PERIOD. BUT
GIVEN THE MAGNITUDE OF COLD AIR AND STEEP LAPSE RATES ALOFT (-2C
AT 850 MB...-30C AT 500 MB LEADING TO 1000-500 MB LAPSE RATES
EXCEEDING 7C/KM) HARD TO IMAGINE WE WONT SEE ANOTHER BATCH OF
SHOWERS DEVELOP THIS AFTERNOON...EITHER UPSTREAM OVER EASTERN
WISCONSIN AND/OR OVER THE LAKE MICHIGAN/NW LOWER MICHIGAN WITHIN
THE LAKE "HEAT PLUME." HAVE SCT-LIKELY SHOWERS IN THE FORECAST
DEVELOPING OVER THE WESTERN PARTS OF THE CWA THIS AFTERNOON INTO
THIS EVENING AS A RESULT.

THUNDER AND SMALL HAIL...NOT OUT OF THE QUESTION GIVEN THE STEEP
LAPSE RATES AND EQUILIBRIUM LEVELS POKING ABOVE -20C.

UPDATE ISSUED AT 651 AM EDT SAT OCT 19 2013

SHOWERS HAVE BEEN SLOW ALL NIGHT TO MOVE INLAND FROM LAKE MI...AND
THAT TREND CONTINUES...THOUGH THERE IS SOMETHING OF A BACK EDGE
PRESSING EASTWARD WEST OF CAD/TVC. HAVE ADJUSTED POP/WX GRIDS THIS
MORNING TO ACCOUNT.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 233 AM EDT SAT OCT 19 2013

FIRST ROUND OF A STEP DOWN PROCESS TO A MUCH COOLER WEATHER REGIME
FIRMLY IN CONTROL OF OUR WEATHER AT THIS EARLY HOUR...COURTESY OF
OVERHEAD TROUGHING IN A REMARKABLY AMPLIFIED NOAM FLOW REGIME.
LATEST RAP HIGH RES ANALYSIS CONFIRMS...WITH H8 TEMPERATURES DIPPING
TO SUB 0C LEVELS ACROSS THE NORTHWEST HALF OF THE AREA. DESPITE
OVERHEAD TROUGHING...MID LEVEL SYNOPTIC DYNAMICS RATHER
NEGLIGIBLE...WITH FIRST WAVE (RESPONSIBLE FOR YESTERDAY`S CONVECTIVE
ACTIVITY) OFF TO OUR NORTHEAST...WITH STRONGER CORE OF MID LEVEL
SUPPORT PINWHEELING IN BASE OF TROUGH AXIS WELL TO OUR SOUTHWEST.
LOW LEVEL FEATURES SOMEWHAT MORE FOCUSED...WITH SURFACE TROUGHING
EXTENDING NORTHEAST TO SOUTHWEST...ESSENTIALLY BISECTING NORTHERN
LOWER MICHIGAN...WITH NOTED H8 TROUGHING JUST OFFSET TO THE WEST OF
THIS SURFACE FRONT. COMBINATION OF ATTENDANT FORCED LOW LEVEL
CONVERGENCE AND FAVORABLE LAKE PROCESSES CONTINUE TO KICK OFF
POCKETS OF SHOWERS...SOME OF WHICH HAVE BEEN LOCALLY HEAVY...
ESPECIALLY ALONG THE LAKE MICHIGAN SHORELINE. SURFACE TEMPERATURES
STILL IN THE 40S AND SURFACE BASED MELTING LAYER AT OR ABOVE 2 KFT
LEADING TO ALL LIQUID SHOWERS. SHORT TERM FORECAST CONCERNS REMAIN
CENTERED ON ADDITIONAL SHOWER POTENTIAL RIGHT THROUGH TONIGHT...AS
WELL AS ADDRESSING THUNDER AND WATERSPOUT CHANCES INTO THIS
EVENING.

REALLY KINDA A LOW CONFIDENCE ENDEAVOR ON FORECASTING SHOWER
EVOLUTION TODAY. NO DOUBT THERMODYNAMIC PROFILES REMAIN VERY
SUPPORTIVE FOR ADDITIONAL LAKE PROCESSES...WITH H8 TEMPERATURES
HOVERING AROUND -2C AND LAKE INDUCED EQUILIBRIUM LEVELS UP AND OVER
20 KFT (LAKE INDUCED CAPE OF AROUND 1.0 J/KG). THAT SAID...
KINEMATICS AND OVERALL SYNOPTIC BACKGROUND SUPPORT NOT NEARLY AS
FAVORABLE FOR WIDESPREAD ORGANIZED LAKE INDUCED SHOWERS. WIND FIELDS
RIGHT UP THROUGH 15 KFT REMAIN RATHER LIGHT AND DISORGANIZED...WITH
LOW LEVEL WINDS STEADILY BACKING THROUGH THE DAY AHEAD OF NEXT
APPROACHING SHORTWAVE TROUGH AND ATTENDANT SURFACE REFLECTION. MAIN
CORE OF ENERGY CURRENTLY TIED TO BASE OF TROUGH AXIS LOOKS TO SLIDE
JUST OFF TO OUR SOUTHEAST...LIKELY NOT HAVING A SIGNIFICANT EFFECT
ON LAKE PROCESS MORPHOLOGY (MAY INCREASE THE ODDS FOR MORE FOCUSED
SHOWERS ACROSS NORTHEAST LOWER THIS MORNING). COMBINE ABOVE WITH
TERRESTRIAL CAPE DEVELOPMENT SIMPLY OVERWHELMING LIMITED CBL
SHEAR...RESULTING IN A DEFINITE CELLULAR COMPONENT TO LAKE SHOWER
ACTIVITY...AND ONE CAN SEE WHY SHOWER COVERAGE REMAINS QUITE
PROBLEMATIC TODAY. SHOWERS WILL NO DOUBT CONTINUE...BUT WILL CONFINE
BETTER COVERAGE CLOSER TO THE LAKE MICHIGAN SHORELINE...WITH BELIEF
OVERALL AREAL COVERAGE WILL DISSIPATE AS THEY MOVE INLAND. SURFACE
BASED CAPE AND H5 TEMPERATURES DIPPING TO -30C WILL DEFINITELY AID
IN AN OVERLAND SHOWER COMPONENT...AND MUCH LIKE YESTERDAY...AN
ISOLATED THUNDERSTORM OR TWO. DEEP MOIST CONVECTION IN SUCH A COLD
ENVIRONMENT WILL DEFINITELY SUPPORT THE THREAT OF BRIEF GRAUPEL
SHOWERS UNDER THE HEAVIER PRECIP CORES. HIGHS TODAY WILL RUN A FEW
DEGREES BELOW NORMAL...WITH AFTERNOON READINGS IN THE 40S AND LOWER
50S.

LAKE PROCESSES LIKELY TO GET A BOOST HEADING INTO THIS EVENING AS
WEAK WAVE AND SURFACE TROUGH/ATTENDANT CORE OF LOW LEVEL CONVERGENCE
CROSS LAKE MICHIGAN. MAY SEE SOME PRETTY HEAVY SHOWERS ALONG THIS
TROUGH AS IT PUSHES ONSHORE...WITH SHOWER COVERAGE ONCE AGAIN
DISSIPATING AS THEY PUSH INLAND. GIVEN MAINTENANCE OF DEEP EQL/S AND
GOOD OVER-WATER CAPE...WILL CONTINUE THUNDER MENTION INTO THIS
EVENING OVER AND NEAR LAKE MICHIGAN. LAKE ENHANCEMENT/SHOWER
COVERAGE BOTH EXPECTED TO DISSIPATE OVERNIGHT AS POST-WAVE
SUBSIDENCE REGIME SPREADS ACROSS AND MOISTURE PROFILES BEGIN TO
THIN.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 233 AM EDT SAT OCT 19 2013

UPPER FLOW IS ANCHORED BY RIDGING ALONG OR JUST OFF THE WEST
COAST...AND BROAD RIDGING IN THE CENTRAL ATLANTIC. IN BETWEEN...
TROFFING REIGNS SUPREME OVER CENTRAL CANADA AND ADJOINING PARTS OF
THE US. THIS PATTERN WILL KEEP NORTHERN MI WX COOL AND UNSETTLED FOR
QUITE SOME TIME. THE REAL FUN ARRIVES TOWARD THE EARLY PART OF NEXT
WEEK...AS THE UPPER LOW NOW OVER NW HUDSON BAY DROPS SOUTHWARD INTO
THE NORTHERN GREAT LAKES. PRECIP TRENDS ARE THE MAIN CONCERN THRU
THE FORECAST.

SUNDAY LOOKS LIKE A /RELATIVE/ LULL IN THE SHOWER ACTIVITY. AS THE
UPPER TROF OVER NORTHERN MI TODAY DEPARTS THE EASTERN LAKES...AND AS
THE NEXT LOW DROPS SOUTH ACROSS MANITOBA...A BIT OF SHORTWAVE
RIDGING GETS PUMPED UP INTO THE CENTRAL/NORTHERN LAKES. SUBTLE
SURFACE RIDGING POKES NORTH TOWARD LAKE HURON AT MIDDAY...THEN MOVES
EAST AS RETURN FLOW RAMPS UP LATE IN THE DAY. THOUGH DEEPER DRYING
IS ARRIVING (850-700MB RH LOWERING BELOW 60 PERCENT)...WITH 850MB
TEMPS -2 TO -3C...WOULD STILL EXPECT AT LEAST SCT SHRA IN THE
MORNING IN W TO WSW FLOW AREAS (MAINLY NW LOWER). MAY CATCH A BIT OF
A PRECIP BREAK MIDDAY TO MID AFTERNOON. AFTER THAT...THE NAM MAY BE
OVERDONE IN DEVELOPING A 45KT 850MB JET PUNCHING UP THE SPINE OF
CENTRAL/SOUTHERN LAKE MI. BUT INCREASING RETURN FLOW WARRANTS A
CHANCE OF SHRA RETURNING VERY LATE IN THE DAY IN SOME WESTERN
SECTIONS. MAX TEMPS NEAR 50 TO THE LOWER 50S.

SUN NIGHT/MONDAY...500MB LOW WILL CONTINUE TO DROP TOWARD INTL FALLS
BY MONDAY MORNING...THEN PIVOT TOWARD CENTRAL LAKE SUPERIOR BY
EVENING. THE ASSOCIATED SURFACE LOW WILL DEEPEN TO AROUND 998MB OVER
CENTRAL SUPERIOR BY MORNING MORNING...THEN FILL A BIT AND ELONGATE
TOWARD THE ENE DURING THE DAY.

ON SUNDAY NIGHT...RAIN WILL SPREAD ENE-WARD FROM NORTHERN/CENTRAL
WI...INITIALLY MAINLY NORTH OF A WARM FRONT THAT LIFTS INTO FAR
NORTHERN LOWER MI BY 06Z. THAT FRONT LIFTS ACROSS EASTERN UPPER MI
OVERNIGHT...BUT THE COLD FRONT IS RIGHT BEHIND...CROSSING MOST OF
THE FORECAST AREA FROM WEST TO EAST. THIS BOUNDARY MAY STILL BE
HANGING AROUND EXTREME EASTERN SECTIONS (OSC-APN-DRUMMOND) AT 12Z.
POPS WILL BE HIGHEST NORTH OF A TVC-APN LINE...WHERE THE LOW LEVEL
JET (850MB WINDS PUSHING 50-55KT AT 03Z) PUNCHES ACROSS THE
ADVANCING WARM FRONT. POPS DIMINISH TO CHANCE IN THE FAR SE.

MONDAY IS A DAY DOMINATED BY MID/UPPER-LEVEL DRY SLOTTING...AS THE
WARM CONVEYOR BELT RACES EAST...AND WRAPAROUND MOISTURE REMAINS BACK
ALONG THE WESTERN AND NORTHERN SHORES OF SUPERIOR. HOWEVER...A
SUBSTANTIAL QUANTITY OF COLD AIR WILL BE PUSHING IN AS THE DAY
PROCEEDS. 850MB TEMPS WILL BE IN THE PROCESS OF SLIDING BACK TO OR
BELOW 0C BY 12Z...READINGS CLOSER TO -6C ARE PROGGED BY SUNSET. THE
INCREASING INSTABILITY SHOULD FIGHT OFF THE DRIER AIR ALOFT...AND
SUPPORT AT LEAST SOME SHRA DOWNWIND OF THE LAKES. WHERE EXACTLY THAT
IT IS STILL CONJECTURE...AS DIFFERENT ORIENTATIONS OF THE SURFACE
LOW TO OUR RESULTS IN DIFFERENT FETCHES (FROM W TO SW). WILL SPLIT
THE DIFFERENCE FOR NOW.

MIN TEMPS NEAR 40F TO THE LOWER 40S. MAX TEMPS ONLY 5F WARMER THAN
THAT WEST...10F EAST...WITH FALLING READINGS IN THE PM. BRISK/WINDY
ON MONDAY.

REST OF THE FORECAST...NO MAJOR CHANGES TO THE EXTENDED.
UNSEASONABLY COOL WX WILL CONTINUE. THOUGH THE UPPER LOW ITSELF WILL
LIFT OUT INTO QUEBEC ON TUESDAY/WEDNESDAY...PLENTY OF TROFFING GETS
LEFT BEHIND. OCCASIONAL REINFORCING SHORTWAVES FROM THE NNW WILL
REINFORCE THE TROFFING...AND THE COLDER AIR AT LOW LEVELS. LAKE
EFFECT SHOWERS WILL CONTINUE DOWNWIND OF THE LAKES...AND MAINTAINED
LIKELY POPS IN THE CLASSIC SNOWBELTS. SPEAKING OF SNOW...PRECIP WILL
GET MIXY TO SNOWY AT TIMES...ESPECIALLY AT NIGHT/MORNING AND
ESPECIALLY IN THE HIGH TERRAIN OF NORTHERN LOWER. THOUGH QUITE
UNCERTAIN WHETHER THIS WILL EVER RISE TO THE LEVEL OF A WINTER WX
HEADLINE...THE MENTION OF THE FIRST SNOW OF THE SEASON PRESENTLY IN
THE HAZ WX OUTLOOK IS REASONABLE.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 200 PM EDT SAT OCT 19 2013

GENERALLY VFR CONDITIONS ANTICIPATED AT THE TAF SITES THROUGH THE
NEXT 24 HOURS...WITH MAINLY BKN CIGS. SHOWERS WITH SMALL HAIL WILL
IMPACT NORTHWEST LOWER MICHIGAN...PLN/TVC/MBL...THROUGH THE
AFTERNOON AND INTO THE EVENING. BUT SHOWERS WILL SLOWLY DIMINISH
THROUGH THE NIGHT INTO SUNDAY MORNING.

SOME GUSTINESS WILL BE HAD AT THE TERMINAL SITES THROUGH THIS
AFTERNOON...GUSTS UP TO 20 KNOTS. BUT WINDS DIMINISH TONIGHT AND
REMAIN LIGHTER THROUGH SUNDAY MORNING.

&&

.MARINE...
ISSUED AT 233 AM EDT SAT OCT 19 2013

BIG STORY REMAINS ISOLATED WATERSPOUT POTENTIAL TODAY INTO
THIS EVENING. COMBINATION OF UNSEASONABLY CHILLY AIRMASS/WEAK
PARTIALLY LAKE-DRIVEN SURFACE TROUGH/AND DEEP CONVECTION DEFINITELY
SUPPORT THIS POTENTIAL. PRIMARY THREAT IS EXPECTED ACROSS THE WATERS
OF LAKE MICHIGAN AND LAKE HURON...WITH THE THREAT ENDING OVERNIGHT
AS THE SURFACE TROUGH PASSES. OTHERWISE...MARGINALLY GUSTY GENERAL
WEST FLOW TODAY...ALTHOUGH BOTH WINDS AND WAVES LOOK TO REMAIN BELOW
SCA CRITERIA. WINDS BEGIN TO PICK UP OUT OF THE SOUTHEAST
SUNDAY...BECOMING QUITE GUSTY SUNDAY NIGHT. WINDS VEER SOUTHWEST ON
MONDAY BEHIND PASSAGE OF A STRONG COLD FRONT. HEADLINES WILL
EVENTUALLY BE NEED FOR THE WATERS LATER SUNDAY RIGHT THROUGH MONDAY
(AND LIKELY BEYOND). MAY EVEN SEE GALE CONDITIONS ON NORTHERN LAKE
MICHIGAN ON MONDAY AS STRONG LOW PRESSURE PULLS UP ACROSS LAKE
SUPERIOR.


&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.

&&

$$

UPDATE...BA
SYNOPSIS...JZ
SHORT TERM...MB
LONG TERM...JZ
AVIATION...BA
MARINE...MB








AREA FORECAST DISCUSSION

NWS GAYLORD MI

 1111 AM EDT SAT OCT 19 2013

.SYNOPSIS...
ISSUED AT 233 AM EDT SAT OCT 19 2013

AN ACTIVE AND CHILLY PATTERN WILL REMAIN ACROSS THE GREAT LAKES
RIGHT THROUGH NEXT WEEK. THE MOST SIGNIFICANT LOW PRESSURE SYSTEM IN
THE NEAR FUTURE WILL MOVE SOUTHEAST FROM CENTRAL CANADA THIS
WEEKEND...REACHING LAKE SUPERIOR BY MONDAY MORNING. THE COLDEST AIR
OF THE FALL SEASON SO FAR WILL ENTER THE REGION BEHIND THE LOW
PRESSURE SYSTEM. TEMPERATURES MAY GET COLD ENOUGH NEXT WEEK TO BRING
THE FIRST SNOWFALL OF THE SEASON...ESPECIALLY TO THE INTERIOR
HIGHLANDS OF NORTHERN LOWER MICHIGAN.

&&

.UPDATE...
ISSUED AT 1111 AM EDT SAT OCT 19 2013

SHARP SHORT WAVE TROUGH AND FIRST ROUND OF COLDER AIR NOW SWINGING
THROUGH THE WESTERN GREAT LAKES. ASSOCIATED JET CORE AXIS RUNS
NORTHEASTWARD UP THROUGH THE OHIO VALLEY AND ACROSS FAR SE LOWER
MICHIGAN. LEFT EXIT REGION FORCING HELPING TO DEEPEN LOW PRESSURE
OVER NRN LAKE HURON WITH A TRAILING COLD FRONT/SFC TROUGH AXIS
STRETCHING BACK THROUGH NE LOWER MICHIGAN INTO CENTRAL LOWER
MICHIGAN. BATCH OF FAIRLY WIDESPREAD "WRAP AROUND" RAINFALL
MOVING ACROSS NE LOWER MICHIGAN THIS LATE THIS MORNING RIGHT
BEHIND THE FRONT.

FURTHER WEST...WELL DEFINED DRY SLOT/CLEARING LINE POKING UP INTO
THE WESTERN GREAT LAKES AND NOSING INTO EASTERN UPPER/NW LOWER
MICHIGAN.

REST OF TODAY...PER SATELLITE TRENDS...CLEARING LINE WILL WORK ITS
WAY EASTWARD OVER THE NEXT FEW HOURS AS LOW AMPLITUDE LOW-MID
LEVEL RIDGING SLIDES THROUGH THE REGION. THIS WILL BRING VARYING
DEGREES OF SUNSHINE TO THE CWA...AT LEAST FOR A BRIEF PERIOD. BUT
GIVEN THE MAGNITUDE OF COLD AIR AND STEEP LAPSE RATES ALOFT (-2C
AT 850 MB...-30C AT 500 MB LEADING TO 1000-500 MB LAPSE RATES
EXCEEDING 7C/KM) HARD TO IMAGINE WE WONT SEE ANOTHER BATCH OF
SHOWERS DEVELOP THIS AFTERNOON...EITHER UPSTREAM OVER EASTERN
WISCONSIN AND/OR OVER THE LAKE MICHIGAN/NW LOWER MICHIGAN WITHIN
THE LAKE "HEAT PLUME." HAVE SCT-LIKELY SHOWERS IN THE FORECAST
DEVELOPING OVER THE WESTERN PARTS OF THE CWA THIS AFTERNOON INTO
THIS EVENING AS A RESULT.

THUNDER AND SMALL HAIL...NOT OUT OF THE QUESTION GIVEN THE STEEP
LAPSE RATES AND EQUILIBRIUM LEVELS POKING ABOVE -20C.

UPDATE ISSUED AT 651 AM EDT SAT OCT 19 2013

SHOWERS HAVE BEEN SLOW ALL NIGHT TO MOVE INLAND FROM LAKE MI...AND
THAT TREND CONTINUES...THOUGH THERE IS SOMETHING OF A BACK EDGE
PRESSING EASTWARD WEST OF CAD/TVC. HAVE ADJUSTED POP/WX GRIDS THIS
MORNING TO ACCOUNT.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 233 AM EDT SAT OCT 19 2013

FIRST ROUND OF A STEP DOWN PROCESS TO A MUCH COOLER WEATHER REGIME
FIRMLY IN CONTROL OF OUR WEATHER AT THIS EARLY HOUR...COURTESY OF
OVERHEAD TROUGHING IN A REMARKABLY AMPLIFIED NOAM FLOW REGIME.
LATEST RAP HIGH RES ANALYSIS CONFIRMS...WITH H8 TEMPERATURES DIPPING
TO SUB 0C LEVELS ACROSS THE NORTHWEST HALF OF THE AREA. DESPITE
OVERHEAD TROUGHING...MID LEVEL SYNOPTIC DYNAMICS RATHER
NEGLIGIBLE...WITH FIRST WAVE (RESPONSIBLE FOR YESTERDAY`S CONVECTIVE
ACTIVITY) OFF TO OUR NORTHEAST...WITH STRONGER CORE OF MID LEVEL
SUPPORT PINWHEELING IN BASE OF TROUGH AXIS WELL TO OUR SOUTHWEST.
LOW LEVEL FEATURES SOMEWHAT MORE FOCUSED...WITH SURFACE TROUGHING
EXTENDING NORTHEAST TO SOUTHWEST...ESSENTIALLY BISECTING NORTHERN
LOWER MICHIGAN...WITH NOTED H8 TROUGHING JUST OFFSET TO THE WEST OF
THIS SURFACE FRONT. COMBINATION OF ATTENDANT FORCED LOW LEVEL
CONVERGENCE AND FAVORABLE LAKE PROCESSES CONTINUE TO KICK OFF
POCKETS OF SHOWERS...SOME OF WHICH HAVE BEEN LOCALLY HEAVY...
ESPECIALLY ALONG THE LAKE MICHIGAN SHORELINE. SURFACE TEMPERATURES
STILL IN THE 40S AND SURFACE BASED MELTING LAYER AT OR ABOVE 2 KFT
LEADING TO ALL LIQUID SHOWERS. SHORT TERM FORECAST CONCERNS REMAIN
CENTERED ON ADDITIONAL SHOWER POTENTIAL RIGHT THROUGH TONIGHT...AS
WELL AS ADDRESSING THUNDER AND WATERSPOUT CHANCES INTO THIS
EVENING.

REALLY KINDA A LOW CONFIDENCE ENDEAVOR ON FORECASTING SHOWER
EVOLUTION TODAY. NO DOUBT THERMODYNAMIC PROFILES REMAIN VERY
SUPPORTIVE FOR ADDITIONAL LAKE PROCESSES...WITH H8 TEMPERATURES
HOVERING AROUND -2C AND LAKE INDUCED EQUILIBRIUM LEVELS UP AND OVER
20 KFT (LAKE INDUCED CAPE OF AROUND 1.0 J/KG). THAT SAID...
KINEMATICS AND OVERALL SYNOPTIC BACKGROUND SUPPORT NOT NEARLY AS
FAVORABLE FOR WIDESPREAD ORGANIZED LAKE INDUCED SHOWERS. WIND FIELDS
RIGHT UP THROUGH 15 KFT REMAIN RATHER LIGHT AND DISORGANIZED...WITH
LOW LEVEL WINDS STEADILY BACKING THROUGH THE DAY AHEAD OF NEXT
APPROACHING SHORTWAVE TROUGH AND ATTENDANT SURFACE REFLECTION. MAIN
CORE OF ENERGY CURRENTLY TIED TO BASE OF TROUGH AXIS LOOKS TO SLIDE
JUST OFF TO OUR SOUTHEAST...LIKELY NOT HAVING A SIGNIFICANT EFFECT
ON LAKE PROCESS MORPHOLOGY (MAY INCREASE THE ODDS FOR MORE FOCUSED
SHOWERS ACROSS NORTHEAST LOWER THIS MORNING). COMBINE ABOVE WITH
TERRESTRIAL CAPE DEVELOPMENT SIMPLY OVERWHELMING LIMITED CBL
SHEAR...RESULTING IN A DEFINITE CELLULAR COMPONENT TO LAKE SHOWER
ACTIVITY...AND ONE CAN SEE WHY SHOWER COVERAGE REMAINS QUITE
PROBLEMATIC TODAY. SHOWERS WILL NO DOUBT CONTINUE...BUT WILL CONFINE
BETTER COVERAGE CLOSER TO THE LAKE MICHIGAN SHORELINE...WITH BELIEF
OVERALL AREAL COVERAGE WILL DISSIPATE AS THEY MOVE INLAND. SURFACE
BASED CAPE AND H5 TEMPERATURES DIPPING TO -30C WILL DEFINITELY AID
IN AN OVERLAND SHOWER COMPONENT...AND MUCH LIKE YESTERDAY...AN
ISOLATED THUNDERSTORM OR TWO. DEEP MOIST CONVECTION IN SUCH A COLD
ENVIRONMENT WILL DEFINITELY SUPPORT THE THREAT OF BRIEF GRAUPEL
SHOWERS UNDER THE HEAVIER PRECIP CORES. HIGHS TODAY WILL RUN A FEW
DEGREES BELOW NORMAL...WITH AFTERNOON READINGS IN THE 40S AND LOWER
50S.

LAKE PROCESSES LIKELY TO GET A BOOST HEADING INTO THIS EVENING AS
WEAK WAVE AND SURFACE TROUGH/ATTENDANT CORE OF LOW LEVEL CONVERGENCE
CROSS LAKE MICHIGAN. MAY SEE SOME PRETTY HEAVY SHOWERS ALONG THIS
TROUGH AS IT PUSHES ONSHORE...WITH SHOWER COVERAGE ONCE AGAIN
DISSIPATING AS THEY PUSH INLAND. GIVEN MAINTENANCE OF DEEP EQL/S AND
GOOD OVER-WATER CAPE...WILL CONTINUE THUNDER MENTION INTO THIS
EVENING OVER AND NEAR LAKE MICHIGAN. LAKE ENHANCEMENT/SHOWER
COVERAGE BOTH EXPECTED TO DISSIPATE OVERNIGHT AS POST-WAVE
SUBSIDENCE REGIME SPREADS ACROSS AND MOISTURE PROFILES BEGIN TO
THIN.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 233 AM EDT SAT OCT 19 2013

UPPER FLOW IS ANCHORED BY RIDGING ALONG OR JUST OFF THE WEST
COAST...AND BROAD RIDGING IN THE CENTRAL ATLANTIC. IN BETWEEN...
TROFFING REIGNS SUPREME OVER CENTRAL CANADA AND ADJOINING PARTS OF
THE US. THIS PATTERN WILL KEEP NORTHERN MI WX COOL AND UNSETTLED FOR
QUITE SOME TIME. THE REAL FUN ARRIVES TOWARD THE EARLY PART OF NEXT
WEEK...AS THE UPPER LOW NOW OVER NW HUDSON BAY DROPS SOUTHWARD INTO
THE NORTHERN GREAT LAKES. PRECIP TRENDS ARE THE MAIN CONCERN THRU
THE FORECAST.

SUNDAY LOOKS LIKE A /RELATIVE/ LULL IN THE SHOWER ACTIVITY. AS THE
UPPER TROF OVER NORTHERN MI TODAY DEPARTS THE EASTERN LAKES...AND AS
THE NEXT LOW DROPS SOUTH ACROSS MANITOBA...A BIT OF SHORTWAVE
RIDGING GETS PUMPED UP INTO THE CENTRAL/NORTHERN LAKES. SUBTLE
SURFACE RIDGING POKES NORTH TOWARD LAKE HURON AT MIDDAY...THEN MOVES
EAST AS RETURN FLOW RAMPS UP LATE IN THE DAY. THOUGH DEEPER DRYING
IS ARRIVING (850-700MB RH LOWERING BELOW 60 PERCENT)...WITH 850MB
TEMPS -2 TO -3C...WOULD STILL EXPECT AT LEAST SCT SHRA IN THE
MORNING IN W TO WSW FLOW AREAS (MAINLY NW LOWER). MAY CATCH A BIT OF
A PRECIP BREAK MIDDAY TO MID AFTERNOON. AFTER THAT...THE NAM MAY BE
OVERDONE IN DEVELOPING A 45KT 850MB JET PUNCHING UP THE SPINE OF
CENTRAL/SOUTHERN LAKE MI. BUT INCREASING RETURN FLOW WARRANTS A
CHANCE OF SHRA RETURNING VERY LATE IN THE DAY IN SOME WESTERN
SECTIONS. MAX TEMPS NEAR 50 TO THE LOWER 50S.

SUN NIGHT/MONDAY...500MB LOW WILL CONTINUE TO DROP TOWARD INTL FALLS
BY MONDAY MORNING...THEN PIVOT TOWARD CENTRAL LAKE SUPERIOR BY
EVENING. THE ASSOCIATED SURFACE LOW WILL DEEPEN TO AROUND 998MB OVER
CENTRAL SUPERIOR BY MORNING MORNING...THEN FILL A BIT AND ELONGATE
TOWARD THE ENE DURING THE DAY.

ON SUNDAY NIGHT...RAIN WILL SPREAD ENE-WARD FROM NORTHERN/CENTRAL
WI...INITIALLY MAINLY NORTH OF A WARM FRONT THAT LIFTS INTO FAR
NORTHERN LOWER MI BY 06Z. THAT FRONT LIFTS ACROSS EASTERN UPPER MI
OVERNIGHT...BUT THE COLD FRONT IS RIGHT BEHIND...CROSSING MOST OF
THE FORECAST AREA FROM WEST TO EAST. THIS BOUNDARY MAY STILL BE
HANGING AROUND EXTREME EASTERN SECTIONS (OSC-APN-DRUMMOND) AT 12Z.
POPS WILL BE HIGHEST NORTH OF A TVC-APN LINE...WHERE THE LOW LEVEL
JET (850MB WINDS PUSHING 50-55KT AT 03Z) PUNCHES ACROSS THE
ADVANCING WARM FRONT. POPS DIMINISH TO CHANCE IN THE FAR SE.

MONDAY IS A DAY DOMINATED BY MID/UPPER-LEVEL DRY SLOTTING...AS THE
WARM CONVEYOR BELT RACES EAST...AND WRAPAROUND MOISTURE REMAINS BACK
ALONG THE WESTERN AND NORTHERN SHORES OF SUPERIOR. HOWEVER...A
SUBSTANTIAL QUANTITY OF COLD AIR WILL BE PUSHING IN AS THE DAY
PROCEEDS. 850MB TEMPS WILL BE IN THE PROCESS OF SLIDING BACK TO OR
BELOW 0C BY 12Z...READINGS CLOSER TO -6C ARE PROGGED BY SUNSET. THE
INCREASING INSTABILITY SHOULD FIGHT OFF THE DRIER AIR ALOFT...AND
SUPPORT AT LEAST SOME SHRA DOWNWIND OF THE LAKES. WHERE EXACTLY THAT
IT IS STILL CONJECTURE...AS DIFFERENT ORIENTATIONS OF THE SURFACE
LOW TO OUR RESULTS IN DIFFERENT FETCHES (FROM W TO SW). WILL SPLIT
THE DIFFERENCE FOR NOW.

MIN TEMPS NEAR 40F TO THE LOWER 40S. MAX TEMPS ONLY 5F WARMER THAN
THAT WEST...10F EAST...WITH FALLING READINGS IN THE PM. BRISK/WINDY
ON MONDAY.

REST OF THE FORECAST...NO MAJOR CHANGES TO THE EXTENDED.
UNSEASONABLY COOL WX WILL CONTINUE. THOUGH THE UPPER LOW ITSELF WILL
LIFT OUT INTO QUEBEC ON TUESDAY/WEDNESDAY...PLENTY OF TROFFING GETS
LEFT BEHIND. OCCASIONAL REINFORCING SHORTWAVES FROM THE NNW WILL
REINFORCE THE TROFFING...AND THE COLDER AIR AT LOW LEVELS. LAKE
EFFECT SHOWERS WILL CONTINUE DOWNWIND OF THE LAKES...AND MAINTAINED
LIKELY POPS IN THE CLASSIC SNOWBELTS. SPEAKING OF SNOW...PRECIP WILL
GET MIXY TO SNOWY AT TIMES...ESPECIALLY AT NIGHT/MORNING AND
ESPECIALLY IN THE HIGH TERRAIN OF NORTHERN LOWER. THOUGH QUITE
UNCERTAIN WHETHER THIS WILL EVER RISE TO THE LEVEL OF A WINTER WX
HEADLINE...THE MENTION OF THE FIRST SNOW OF THE SEASON PRESENTLY IN
THE HAZ WX OUTLOOK IS REASONABLE.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 651 AM EDT SAT OCT 19 2013

LOW VFR/HIGH MVFR CIGS WILL PERSIST ACROSS MOST OF NRN LWR MICHIGAN
THRU TONIGHT...AS NMRS LAKE ENHANCED RAIN SHOWERS CONTINUE TO
STREAM INTO THE REGION. NW LWR MICHIGAN (PLN/TVC/MBL) WILL SEE
THE MOST FREQUENT SHOWER ACTIVITY. LOW LEVEL WINDS WILL BACK TO
THE WEST BY MIDDAY SATURDAY AHEAD OF THE NEXT WAVE OF LOW PRESSURE
AS A DEEP 500 MB TROUGH DIGS INTO THE UPPER MISSISSIPPI VALLEY.


&&

.MARINE...
ISSUED AT 233 AM EDT SAT OCT 19 2013

BIG STORY REMAINS ISOLATED WATERSPOUT POTENTIAL TODAY INTO
THIS EVENING. COMBINATION OF UNSEASONABLY CHILLY AIRMASS/WEAK
PARTIALLY LAKE-DRIVEN SURFACE TROUGH/AND DEEP CONVECTION DEFINITELY
SUPPORT THIS POTENTIAL. PRIMARY THREAT IS EXPECTED ACROSS THE WATERS
OF LAKE MICHIGAN AND LAKE HURON...WITH THE THREAT ENDING OVERNIGHT
AS THE SURFACE TROUGH PASSES. OTHERWISE...MARGINALLY GUSTY GENERAL
WEST FLOW TODAY...ALTHOUGH BOTH WINDS AND WAVES LOOK TO REMAIN BELOW
SCA CRITERIA. WINDS BEGIN TO PICK UP OUT OF THE SOUTHEAST
SUNDAY...BECOMING QUITE GUSTY SUNDAY NIGHT. WINDS VEER SOUTHWEST ON
MONDAY BEHIND PASSAGE OF A STRONG COLD FRONT. HEADLINES WILL
EVENTUALLY BE NEED FOR THE WATERS LATER SUNDAY RIGHT THROUGH MONDAY
(AND LIKELY BEYOND). MAY EVEN SEE GALE CONDITIONS ON NORTHERN LAKE
MICHIGAN ON MONDAY AS STRONG LOW PRESSURE PULLS UP ACROSS LAKE
SUPERIOR.


&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.

&&

$$

UPDATE...BA
SYNOPSIS...JZ
SHORT TERM...MB
LONG TERM...JZ
AVIATION...JZ
MARINE...MB








AREA FORECAST DISCUSSION

NWS GAYLORD MI

 652 AM EDT SAT OCT 19 2013

.SYNOPSIS...
ISSUED AT 233 AM EDT SAT OCT 19 2013

AN ACTIVE AND CHILLY PATTERN WILL REMAIN ACROSS THE GREAT LAKES
RIGHT THROUGH NEXT WEEK. THE MOST SIGNIFICANT LOW PRESSURE SYSTEM IN
THE NEAR FUTURE WILL MOVE SOUTHEAST FROM CENTRAL CANADA THIS
WEEKEND...REACHING LAKE SUPERIOR BY MONDAY MORNING. THE COLDEST AIR
OF THE FALL SEASON SO FAR WILL ENTER THE REGION BEHIND THE LOW
PRESSURE SYSTEM. TEMPERATURES MAY GET COLD ENOUGH NEXT WEEK TO BRING
THE FIRST SNOWFALL OF THE SEASON...ESPECIALLY TO THE INTERIOR
HIGHLANDS OF NORTHERN LOWER MICHIGAN.

&&

.UPDATE...
ISSUED AT 651 AM EDT SAT OCT 19 2013

SHOWERS HAVE BEEN SLOW ALL NIGHT TO MOVE INLAND FROM LAKE MI...AND
THAT TREND CONTINUES...THOUGH THERE IS SOMETHING OF A BACK EDGE
PRESSING EASTWARD WEST OF CAD/TVC. HAVE ADJUSTED POP/WX GRIDS THIS
MORNING TO ACCOUNT.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 233 AM EDT SAT OCT 19 2013

FIRST ROUND OF A STEP DOWN PROCESS TO A MUCH COOLER WEATHER REGIME
FIRMLY IN CONTROL OF OUR WEATHER AT THIS EARLY HOUR...COURTESY OF
OVERHEAD TROUGHING IN A REMARKABLY AMPLIFIED NOAM FLOW REGIME.
LATEST RAP HIGH RES ANALYSIS CONFIRMS...WITH H8 TEMPERATURES DIPPING
TO SUB 0C LEVELS ACROSS THE NORTHWEST HALF OF THE AREA. DESPITE
OVERHEAD TROUGHING...MID LEVEL SYNOPTIC DYNAMICS RATHER
NEGLIGIBLE...WITH FIRST WAVE (RESPONSIBLE FOR YESTERDAY`S CONVECTIVE
ACTIVITY) OFF TO OUR NORTHEAST...WITH STRONGER CORE OF MID LEVEL
SUPPORT PINWHEELING IN BASE OF TROUGH AXIS WELL TO OUR SOUTHWEST.
LOW LEVEL FEATURES SOMEWHAT MORE FOCUSED...WITH SURFACE TROUGHING
EXTENDING NORTHEAST TO SOUTHWEST...ESSENTIALLY BISECTING NORTHERN
LOWER MICHIGAN...WITH NOTED H8 TROUGHING JUST OFFSET TO THE WEST OF
THIS SURFACE FRONT. COMBINATION OF ATTENDANT FORCED LOW LEVEL
CONVERGENCE AND FAVORABLE LAKE PROCESSES CONTINUE TO KICK OFF
POCKETS OF SHOWERS...SOME OF WHICH HAVE BEEN LOCALLY HEAVY...
ESPECIALLY ALONG THE LAKE MICHIGAN SHORELINE. SURFACE TEMPERATURES
STILL IN THE 40S AND SURFACE BASED MELTING LAYER AT OR ABOVE 2 KFT
LEADING TO ALL LIQUID SHOWERS. SHORT TERM FORECAST CONCERNS REMAIN
CENTERED ON ADDITIONAL SHOWER POTENTIAL RIGHT THROUGH TONIGHT...AS
WELL AS ADDRESSING THUNDER AND WATERSPOUT CHANCES INTO THIS
EVENING.

REALLY KINDA A LOW CONFIDENCE ENDEAVOR ON FORECASTING SHOWER
EVOLUTION TODAY. NO DOUBT THERMODYNAMIC PROFILES REMAIN VERY
SUPPORTIVE FOR ADDITIONAL LAKE PROCESSES...WITH H8 TEMPERATURES
HOVERING AROUND -2C AND LAKE INDUCED EQUILIBRIUM LEVELS UP AND OVER
20 KFT (LAKE INDUCED CAPE OF AROUND 1.0 J/KG). THAT SAID...
KINEMATICS AND OVERALL SYNOPTIC BACKGROUND SUPPORT NOT NEARLY AS
FAVORABLE FOR WIDESPREAD ORGANIZED LAKE INDUCED SHOWERS. WIND FIELDS
RIGHT UP THROUGH 15 KFT REMAIN RATHER LIGHT AND DISORGANIZED...WITH
LOW LEVEL WINDS STEADILY BACKING THROUGH THE DAY AHEAD OF NEXT
APPROACHING SHORTWAVE TROUGH AND ATTENDANT SURFACE REFLECTION. MAIN
CORE OF ENERGY CURRENTLY TIED TO BASE OF TROUGH AXIS LOOKS TO SLIDE
JUST OFF TO OUR SOUTHEAST...LIKELY NOT HAVING A SIGNIFICANT EFFECT
ON LAKE PROCESS MORPHOLOGY (MAY INCREASE THE ODDS FOR MORE FOCUSED
SHOWERS ACROSS NORTHEAST LOWER THIS MORNING). COMBINE ABOVE WITH
TERRESTRIAL CAPE DEVELOPMENT SIMPLY OVERWHELMING LIMITED CBL
SHEAR...RESULTING IN A DEFINITE CELLULAR COMPONENT TO LAKE SHOWER
ACTIVITY...AND ONE CAN SEE WHY SHOWER COVERAGE REMAINS QUITE
PROBLEMATIC TODAY. SHOWERS WILL NO DOUBT CONTINUE...BUT WILL CONFINE
BETTER COVERAGE CLOSER TO THE LAKE MICHIGAN SHORELINE...WITH BELIEF
OVERALL AREAL COVERAGE WILL DISSIPATE AS THEY MOVE INLAND. SURFACE
BASED CAPE AND H5 TEMPERATURES DIPPING TO -30C WILL DEFINITELY AID
IN AN OVERLAND SHOWER COMPONENT...AND MUCH LIKE YESTERDAY...AN
ISOLATED THUNDERSTORM OR TWO. DEEP MOIST CONVECTION IN SUCH A COLD
ENVIRONMENT WILL DEFINITELY SUPPORT THE THREAT OF BRIEF GRAUPEL
SHOWERS UNDER THE HEAVIER PRECIP CORES. HIGHS TODAY WILL RUN A FEW
DEGREES BELOW NORMAL...WITH AFTERNOON READINGS IN THE 40S AND LOWER
50S.

LAKE PROCESSES LIKELY TO GET A BOOST HEADING INTO THIS EVENING AS
WEAK WAVE AND SURFACE TROUGH/ATTENDANT CORE OF LOW LEVEL CONVERGENCE
CROSS LAKE MICHIGAN. MAY SEE SOME PRETTY HEAVY SHOWERS ALONG THIS
TROUGH AS IT PUSHES ONSHORE...WITH SHOWER COVERAGE ONCE AGAIN
DISSIPATING AS THEY PUSH INLAND. GIVEN MAINTENANCE OF DEEP EQL/S AND
GOOD OVER-WATER CAPE...WILL CONTINUE THUNDER MENTION INTO THIS
EVENING OVER AND NEAR LAKE MICHIGAN. LAKE ENHANCEMENT/SHOWER
COVERAGE BOTH EXPECTED TO DISSIPATE OVERNIGHT AS POST-WAVE
SUBSIDENCE REGIME SPREADS ACROSS AND MOISTURE PROFILES BEGIN TO
THIN.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 233 AM EDT SAT OCT 19 2013

UPPER FLOW IS ANCHORED BY RIDGING ALONG OR JUST OFF THE WEST
COAST...AND BROAD RIDGING IN THE CENTRAL ATLANTIC. IN BETWEEN...
TROFFING REIGNS SUPREME OVER CENTRAL CANADA AND ADJOINING PARTS OF
THE US. THIS PATTERN WILL KEEP NORTHERN MI WX COOL AND UNSETTLED FOR
QUITE SOME TIME. THE REAL FUN ARRIVES TOWARD THE EARLY PART OF NEXT
WEEK...AS THE UPPER LOW NOW OVER NW HUDSON BAY DROPS SOUTHWARD INTO
THE NORTHERN GREAT LAKES. PRECIP TRENDS ARE THE MAIN CONCERN THRU
THE FORECAST.

SUNDAY LOOKS LIKE A /RELATIVE/ LULL IN THE SHOWER ACTIVITY. AS THE
UPPER TROF OVER NORTHERN MI TODAY DEPARTS THE EASTERN LAKES...AND AS
THE NEXT LOW DROPS SOUTH ACROSS MANITOBA...A BIT OF SHORTWAVE
RIDGING GETS PUMPED UP INTO THE CENTRAL/NORTHERN LAKES. SUBTLE
SURFACE RIDGING POKES NORTH TOWARD LAKE HURON AT MIDDAY...THEN MOVES
EAST AS RETURN FLOW RAMPS UP LATE IN THE DAY. THOUGH DEEPER DRYING
IS ARRIVING (850-700MB RH LOWERING BELOW 60 PERCENT)...WITH 850MB
TEMPS -2 TO -3C...WOULD STILL EXPECT AT LEAST SCT SHRA IN THE
MORNING IN W TO WSW FLOW AREAS (MAINLY NW LOWER). MAY CATCH A BIT OF
A PRECIP BREAK MIDDAY TO MID AFTERNOON. AFTER THAT...THE NAM MAY BE
OVERDONE IN DEVELOPING A 45KT 850MB JET PUNCHING UP THE SPINE OF
CENTRAL/SOUTHERN LAKE MI. BUT INCREASING RETURN FLOW WARRANTS A
CHANCE OF SHRA RETURNING VERY LATE IN THE DAY IN SOME WESTERN
SECTIONS. MAX TEMPS NEAR 50 TO THE LOWER 50S.

SUN NIGHT/MONDAY...500MB LOW WILL CONTINUE TO DROP TOWARD INTL FALLS
BY MONDAY MORNING...THEN PIVOT TOWARD CENTRAL LAKE SUPERIOR BY
EVENING. THE ASSOCIATED SURFACE LOW WILL DEEPEN TO AROUND 998MB OVER
CENTRAL SUPERIOR BY MORNING MORNING...THEN FILL A BIT AND ELONGATE
TOWARD THE ENE DURING THE DAY.

ON SUNDAY NIGHT...RAIN WILL SPREAD ENE-WARD FROM NORTHERN/CENTRAL
WI...INITIALLY MAINLY NORTH OF A WARM FRONT THAT LIFTS INTO FAR
NORTHERN LOWER MI BY 06Z. THAT FRONT LIFTS ACROSS EASTERN UPPER MI
OVERNIGHT...BUT THE COLD FRONT IS RIGHT BEHIND...CROSSING MOST OF
THE FORECAST AREA FROM WEST TO EAST. THIS BOUNDARY MAY STILL BE
HANGING AROUND EXTREME EASTERN SECTIONS (OSC-APN-DRUMMOND) AT 12Z.
POPS WILL BE HIGHEST NORTH OF A TVC-APN LINE...WHERE THE LOW LEVEL
JET (850MB WINDS PUSHING 50-55KT AT 03Z) PUNCHES ACROSS THE
ADVANCING WARM FRONT. POPS DIMINISH TO CHANCE IN THE FAR SE.

MONDAY IS A DAY DOMINATED BY MID/UPPER-LEVEL DRY SLOTTING...AS THE
WARM CONVEYOR BELT RACES EAST...AND WRAPAROUND MOISTURE REMAINS BACK
ALONG THE WESTERN AND NORTHERN SHORES OF SUPERIOR. HOWEVER...A
SUBSTANTIAL QUANTITY OF COLD AIR WILL BE PUSHING IN AS THE DAY
PROCEEDS. 850MB TEMPS WILL BE IN THE PROCESS OF SLIDING BACK TO OR
BELOW 0C BY 12Z...READINGS CLOSER TO -6C ARE PROGGED BY SUNSET. THE
INCREASING INSTABILITY SHOULD FIGHT OFF THE DRIER AIR ALOFT...AND
SUPPORT AT LEAST SOME SHRA DOWNWIND OF THE LAKES. WHERE EXACTLY THAT
IT IS STILL CONJECTURE...AS DIFFERENT ORIENTATIONS OF THE SURFACE
LOW TO OUR RESULTS IN DIFFERENT FETCHES (FROM W TO SW). WILL SPLIT
THE DIFFERENCE FOR NOW.

MIN TEMPS NEAR 40F TO THE LOWER 40S. MAX TEMPS ONLY 5F WARMER THAN
THAT WEST...10F EAST...WITH FALLING READINGS IN THE PM. BRISK/WINDY
ON MONDAY.

REST OF THE FORECAST...NO MAJOR CHANGES TO THE EXTENDED.
UNSEASONABLY COOL WX WILL CONTINUE. THOUGH THE UPPER LOW ITSELF WILL
LIFT OUT INTO QUEBEC ON TUESDAY/WEDNESDAY...PLENTY OF TROFFING GETS
LEFT BEHIND. OCCASIONAL REINFORCING SHORTWAVES FROM THE NNW WILL
REINFORCE THE TROFFING...AND THE COLDER AIR AT LOW LEVELS. LAKE
EFFECT SHOWERS WILL CONTINUE DOWNWIND OF THE LAKES...AND MAINTAINED
LIKELY POPS IN THE CLASSIC SNOWBELTS. SPEAKING OF SNOW...PRECIP WILL
GET MIXY TO SNOWY AT TIMES...ESPECIALLY AT NIGHT/MORNING AND
ESPECIALLY IN THE HIGH TERRAIN OF NORTHERN LOWER. THOUGH QUITE
UNCERTAIN WHETHER THIS WILL EVER RISE TO THE LEVEL OF A WINTER WX
HEADLINE...THE MENTION OF THE FIRST SNOW OF THE SEASON PRESENTLY IN
THE HAZ WX OUTLOOK IS REASONABLE.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 651 AM EDT SAT OCT 19 2013

LOW VFR/HIGH MVFR CIGS WILL PERSIST ACROSS MOST OF NRN LWR MICHIGAN
THRU TONIGHT...AS NMRS LAKE ENHANCED RAIN SHOWERS CONTINUE TO
STREAM INTO THE REGION. NW LWR MICHIGAN (PLN/TVC/MBL) WILL SEE
THE MOST FREQUENT SHOWER ACTIVITY. LOW LEVEL WINDS WILL BACK TO
THE WEST BY MIDDAY SATURDAY AHEAD OF THE NEXT WAVE OF LOW PRESSURE
AS A DEEP 500 MB TROUGH DIGS INTO THE UPPER MISSISSIPPI VALLEY.

&&

.MARINE...
ISSUED AT 233 AM EDT SAT OCT 19 2013

BIG STORY REMAINS ISOLATED WATERSPOUT POTENTIAL TODAY INTO
THIS EVENING. COMBINATION OF UNSEASONABLY CHILLY AIRMASS/WEAK
PARTIALLY LAKE-DRIVEN SURFACE TROUGH/AND DEEP CONVECTION DEFINITELY
SUPPORT THIS POTENTIAL. PRIMARY THREAT IS EXPECTED ACROSS THE WATERS
OF LAKE MICHIGAN AND LAKE HURON...WITH THE THREAT ENDING OVERNIGHT
AS THE SURFACE TROUGH PASSES. OTHERWISE...MARGINALLY GUSTY GENERAL
WEST FLOW TODAY...ALTHOUGH BOTH WINDS AND WAVES LOOK TO REMAIN BELOW
SCA CRITERIA. WINDS BEGIN TO PICK UP OUT OF THE SOUTHEAST
SUNDAY...BECOMING QUITE GUSTY SUNDAY NIGHT. WINDS VEER SOUTHWEST ON
MONDAY BEHIND PASSAGE OF A STRONG COLD FRONT. HEADLINES WILL
EVENTUALLY BE NEED FOR THE WATERS LATER SUNDAY RIGHT THROUGH MONDAY
(AND LIKELY BEYOND). MAY EVEN SEE GALE CONDITIONS ON NORTHERN LAKE
MICHIGAN ON MONDAY AS STRONG LOW PRESSURE PULLS UP ACROSS LAKE
SUPERIOR.


&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.

&&

$$

UPDATE...JZ
SYNOPSIS...JZ
SHORT TERM...MB
LONG TERM...JZ
AVIATION...JZ
MARINE...MB







AREA FORECAST DISCUSSION

NWS GAYLORD MI

 236 AM EDT SAT OCT 19 2013

.SYNOPSIS...
ISSUED AT 233 AM EDT SAT OCT 19 2013

AN ACTIVE AND CHILLY PATTERN WILL REMAIN ACROSS THE GREAT LAKES
RIGHT THROUGH NEXT WEEK. THE MOST SIGNIFICANT LOW PRESSURE SYSTEM IN
THE NEAR FUTURE WILL MOVE SOUTHEAST FROM CENTRAL CANADA THIS
WEEKEND...REACHING LAKE SUPERIOR BY MONDAY MORNING. THE COLDEST AIR
OF THE FALL SEASON SO FAR WILL ENTER THE REGION BEHIND THE LOW
PRESSURE SYSTEM. TEMPERATURES MAY GET COLD ENOUGH NEXT WEEK TO BRING
THE FIRST SNOWFALL OF THE SEASON...ESPECIALLY TO THE INTERIOR
HIGHLANDS OF NORTHERN LOWER MICHIGAN.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 233 AM EDT SAT OCT 19 2013

FIRST ROUND OF A STEP DOWN PROCESS TO A MUCH COOLER WEATHER REGIME
FIRMLY IN CONTROL OF OUR WEATHER AT THIS EARLY HOUR...COURTESY OF
OVERHEAD TROUGHING IN A REMARKABLY AMPLIFIED NOAM FLOW REGIME.
LATEST RAP HIGH RES ANALYSIS CONFIRMS...WITH H8 TEMPERATURES DIPPING
TO SUB 0C LEVELS ACROSS THE NORTHWEST HALF OF THE AREA. DESPITE
OVERHEAD TROUGHING...MID LEVEL SYNOPTIC DYNAMICS RATHER
NEGLIGIBLE...WITH FIRST WAVE (RESPONSIBLE FOR YESTERDAY`S CONVECTIVE
ACTIVITY) OFF TO OUR NORTHEAST...WITH STRONGER CORE OF MID LEVEL
SUPPORT PINWHEELING IN BASE OF TROUGH AXIS WELL TO OUR SOUTHWEST.
LOW LEVEL FEATURES SOMEWHAT MORE FOCUSED...WITH SURFACE TROUGHING
EXTENDING NORTHEAST TO SOUTHWEST...ESSENTIALLY BISECTING NORTHERN
LOWER MICHIGAN...WITH NOTED H8 TROUGHING JUST OFFSET TO THE WEST OF
THIS SURFACE FRONT. COMBINATION OF ATTENDANT FORCED LOW LEVEL
CONVERGENCE AND FAVORABLE LAKE PROCESSES CONTINUE TO KICK OFF
POCKETS OF SHOWERS...SOME OF WHICH HAVE BEEN LOCALLY HEAVY...
ESPECIALLY ALONG THE LAKE MICHIGAN SHORELINE. SURFACE TEMPERATURES
STILL IN THE 40S AND SURFACE BASED MELTING LAYER AT OR ABOVE 2 KFT
LEADING TO ALL LIQUID SHOWERS. SHORT TERM FORECAST CONCERNS REMAIN
CENTERED ON ADDITIONAL SHOWER POTENTIAL RIGHT THROUGH TONIGHT...AS
WELL AS ADDRESSING THUNDER AND WATERSPOUT CHANCES INTO THIS
EVENING.

REALLY KINDA A LOW CONFIDENCE ENDEAVOR ON FORECASTING SHOWER
EVOLUTION TODAY. NO DOUBT THERMODYNAMIC PROFILES REMAIN VERY
SUPPORTIVE FOR ADDITIONAL LAKE PROCESSES...WITH H8 TEMPERATURES
HOVERING AROUND -2C AND LAKE INDUCED EQUILIBRIUM LEVELS UP AND OVER
20 KFT (LAKE INDUCED CAPE OF AROUND 1.0 J/KG). THAT SAID...
KINEMATICS AND OVERALL SYNOPTIC BACKGROUND SUPPORT NOT NEARLY AS
FAVORABLE FOR WIDESPREAD ORGANIZED LAKE INDUCED SHOWERS. WIND FIELDS
RIGHT UP THROUGH 15 KFT REMAIN RATHER LIGHT AND DISORGANIZED...WITH
LOW LEVEL WINDS STEADILY BACKING THROUGH THE DAY AHEAD OF NEXT
APPROACHING SHORTWAVE TROUGH AND ATTENDANT SURFACE REFLECTION. MAIN
CORE OF ENERGY CURRENTLY TIED TO BASE OF TROUGH AXIS LOOKS TO SLIDE
JUST OFF TO OUR SOUTHEAST...LIKELY NOT HAVING A SIGNIFICANT EFFECT
ON LAKE PROCESS MORPHOLOGY (MAY INCREASE THE ODDS FOR MORE FOCUSED
SHOWERS ACROSS NORTHEAST LOWER THIS MORNING). COMBINE ABOVE WITH
TERRESTRIAL CAPE DEVELOPMENT SIMPLY OVERWHELMING LIMITED CBL
SHEAR...RESULTING IN A DEFINITE CELLULAR COMPONENT TO LAKE SHOWER
ACTIVITY...AND ONE CAN SEE WHY SHOWER COVERAGE REMAINS QUITE
PROBLEMATIC TODAY. SHOWERS WILL NO DOUBT CONTINUE...BUT WILL CONFINE
BETTER COVERAGE CLOSER TO THE LAKE MICHIGAN SHORELINE...WITH BELIEF
OVERALL AREAL COVERAGE WILL DISSIPATE AS THEY MOVE INLAND. SURFACE
BASED CAPE AND H5 TEMPERATURES DIPPING TO -30C WILL DEFINITELY AID
IN AN OVERLAND SHOWER COMPONENT...AND MUCH LIKE YESTERDAY...AN
ISOLATED THUNDERSTORM OR TWO. DEEP MOIST CONVECTION IN SUCH A COLD
ENVIRONMENT WILL DEFINITELY SUPPORT THE THREAT OF BRIEF GRAUPEL
SHOWERS UNDER THE HEAVIER PRECIP CORES. HIGHS TODAY WILL RUN A FEW
DEGREES BELOW NORMAL...WITH AFTERNOON READINGS IN THE 40S AND LOWER
50S.

LAKE PROCESSES LIKELY TO GET A BOOST HEADING INTO THIS EVENING AS
WEAK WAVE AND SURFACE TROUGH/ATTENDANT CORE OF LOW LEVEL CONVERGENCE
CROSS LAKE MICHIGAN. MAY SEE SOME PRETTY HEAVY SHOWERS ALONG THIS
TROUGH AS IT PUSHES ONSHORE...WITH SHOWER COVERAGE ONCE AGAIN
DISSIPATING AS THEY PUSH INLAND. GIVEN MAINTENANCE OF DEEP EQL/S AND
GOOD OVER-WATER CAPE...WILL CONTINUE THUNDER MENTION INTO THIS
EVENING OVER AND NEAR LAKE MICHIGAN. LAKE ENHANCEMENT/SHOWER
COVERAGE BOTH EXPECTED TO DISSIPATE OVERNIGHT AS POST-WAVE
SUBSIDENCE REGIME SPREADS ACROSS AND MOISTURE PROFILES BEGIN TO
THIN.

&&

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 233 AM EDT SAT OCT 19 2013

UPPER FLOW IS ANCHORED BY RIDGING ALONG OR JUST OFF THE WEST
COAST...AND BROAD RIDGING IN THE CENTRAL ATLANTIC. IN BETWEEN...
TROFFING REIGNS SUPREME OVER CENTRAL CANADA AND ADJOINING PARTS OF
THE US. THIS PATTERN WILL KEEP NORTHERN MI WX COOL AND UNSETTLED FOR
QUITE SOME TIME. THE REAL FUN ARRIVES TOWARD THE EARLY PART OF NEXT
WEEK...AS THE UPPER LOW NOW OVER NW HUDSON BAY DROPS SOUTHWARD INTO
THE NORTHERN GREAT LAKES. PRECIP TRENDS ARE THE MAIN CONCERN THRU
THE FORECAST.

SUNDAY LOOKS LIKE A /RELATIVE/ LULL IN THE SHOWER ACTIVITY. AS THE
UPPER TROF OVER NORTHERN MI TODAY DEPARTS THE EASTERN LAKES...AND AS
THE NEXT LOW DROPS SOUTH ACROSS MANITOBA...A BIT OF SHORTWAVE
RIDGING GETS PUMPED UP INTO THE CENTRAL/NORTHERN LAKES. SUBTLE
SURFACE RIDGING POKES NORTH TOWARD LAKE HURON AT MIDDAY...THEN MOVES
EAST AS RETURN FLOW RAMPS UP LATE IN THE DAY. THOUGH DEEPER DRYING
IS ARRIVING (850-700MB RH LOWERING BELOW 60 PERCENT)...WITH 850MB
TEMPS -2 TO -3C...WOULD STILL EXPECT AT LEAST SCT SHRA IN THE
MORNING IN W TO WSW FLOW AREAS (MAINLY NW LOWER). MAY CATCH A BIT OF
A PRECIP BREAK MIDDAY TO MID AFTERNOON. AFTER THAT...THE NAM MAY BE
OVERDONE IN DEVELOPING A 45KT 850MB JET PUNCHING UP THE SPINE OF
CENTRAL/SOUTHERN LAKE MI. BUT INCREASING RETURN FLOW WARRANTS A
CHANCE OF SHRA RETURNING VERY LATE IN THE DAY IN SOME WESTERN
SECTIONS. MAX TEMPS NEAR 50 TO THE LOWER 50S.

SUN NIGHT/MONDAY...500MB LOW WILL CONTINUE TO DROP TOWARD INTL FALLS
BY MONDAY MORNING...THEN PIVOT TOWARD CENTRAL LAKE SUPERIOR BY
EVENING. THE ASSOCIATED SURFACE LOW WILL DEEPEN TO AROUND 998MB OVER
CENTRAL SUPERIOR BY MORNING MORNING...THEN FILL A BIT AND ELONGATE
TOWARD THE ENE DURING THE DAY.

ON SUNDAY NIGHT...RAIN WILL SPREAD ENE-WARD FROM NORTHERN/CENTRAL
WI...INITIALLY MAINLY NORTH OF A WARM FRONT THAT LIFTS INTO FAR
NORTHERN LOWER MI BY 06Z. THAT FRONT LIFTS ACROSS EASTERN UPPER MI
OVERNIGHT...BUT THE COLD FRONT IS RIGHT BEHIND...CROSSING MOST OF
THE FORECAST AREA FROM WEST TO EAST. THIS BOUNDARY MAY STILL BE
HANGING AROUND EXTREME EASTERN SECTIONS (OSC-APN-DRUMMOND) AT 12Z.
POPS WILL BE HIGHEST NORTH OF A TVC-APN LINE...WHERE THE LOW LEVEL
JET (850MB WINDS PUSHING 50-55KT AT 03Z) PUNCHES ACROSS THE
ADVANCING WARM FRONT. POPS DIMINISH TO CHANCE IN THE FAR SE.

MONDAY IS A DAY DOMINATED BY MID/UPPER-LEVEL DRY SLOTTING...AS THE
WARM CONVEYOR BELT RACES EAST...AND WRAPAROUND MOISTURE REMAINS BACK
ALONG THE WESTERN AND NORTHERN SHORES OF SUPERIOR. HOWEVER...A
SUBSTANTIAL QUANTITY OF COLD AIR WILL BE PUSHING IN AS THE DAY
PROCEEDS. 850MB TEMPS WILL BE IN THE PROCESS OF SLIDING BACK TO OR
BELOW 0C BY 12Z...READINGS CLOSER TO -6C ARE PROGGED BY SUNSET. THE
INCREASING INSTABILITY SHOULD FIGHT OFF THE DRIER AIR ALOFT...AND
SUPPORT AT LEAST SOME SHRA DOWNWIND OF THE LAKES. WHERE EXACTLY THAT
IT IS STILL CONJECTURE...AS DIFFERENT ORIENTATIONS OF THE SURFACE
LOW TO OUR RESULTS IN DIFFERENT FETCHES (FROM W TO SW). WILL SPLIT
THE DIFFERENCE FOR NOW.

MIN TEMPS NEAR 40F TO THE LOWER 40S. MAX TEMPS ONLY 5F WARMER THAN
THAT WEST...10F EAST...WITH FALLING READINGS IN THE PM. BRISK/WINDY
ON MONDAY.

REST OF THE FORECAST...NO MAJOR CHANGES TO THE EXTENDED.
UNSEASONABLY COOL WX WILL CONTINUE. THOUGH THE UPPER LOW ITSELF WILL
LIFT OUT INTO QUEBEC ON TUESDAY/WEDNESDAY...PLENTY OF TROFFING GETS
LEFT BEHIND. OCCASIONAL REINFORCING SHORTWAVES FROM THE NNW WILL
REINFORCE THE TROFFING...AND THE COLDER AIR AT LOW LEVELS. LAKE
EFFECT SHOWERS WILL CONTINUE DOWNWIND OF THE LAKES...AND MAINTAINED
LIKELY POPS IN THE CLASSIC SNOWBELTS. SPEAKING OF SNOW...PRECIP WILL
GET MIXY TO SNOWY AT TIMES...ESPECIALLY AT NIGHT/MORNING AND
ESPECIALLY IN THE HIGH TERRAIN OF NORTHERN LOWER. THOUGH QUITE
UNCERTAIN WHETHER THIS WILL EVER RISE TO THE LEVEL OF A WINTER WX
HEADLINE...THE MENTION OF THE FIRST SNOW OF THE SEASON PRESENTLY IN
THE HAZ WX OUTLOOK IS REASONABLE.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 120 AM EDT SAT OCT 19 2013

LOW VFR/HIGH MVFR CIGS WILL PERSIST ACROSS MOST OF NRN LWR MICHIGAN
THRU SATURDAY NIGHT AS NMRS LAKE ENHANCED RAIN SHOWERS CONTINUE TO
STREAM INTO THE REGION. THE EXCEPTION WILL BE APN WHERE A TEMPORARY
DIMINISH IN CLOUD COVER TONIGHT HAS ALLOWED FOR SOME FOG DEVELOPMENT
AND IFR CONDITIONS. SOME FOG WILL PERSIST IN THIS AREA THRU EARLY TO
MID MORNING DESPITE INCREASING CLOUDS LATE TONIGHT. NW LWR MICHIGAN
(PLN/TVC/MBL) WILL SEE THE MOST FREQUENT SHOWER ACTIVITY AS W/SW LOW
LEVEL FLOW THIS EVENING SHIFTS TO THE NW OVERNIGHT AS A TROUGH
SWINGS THRU MICHIGAN. LOW LEVEL WINDS WILL BACK TO THE WEST BY
MIDDAY SATURDAY AHEAD OF THE NEXT WAVE OF LOW PRESSURE AS A DEEP 500
MB TROUGH DIGS INTO THE UPPER MISSISSIPPI VALLEY.

&&

.MARINE...
ISSUED AT 233 AM EDT SAT OCT 19 2013

BIG STORY REMAINS ISOLATED WATERSPOUT POTENTIAL TODAY INTO
THIS EVENING. COMBINATION OF UNSEASONABLY CHILLY AIRMASS/WEAK
PARTIALLY LAKE-DRIVEN SURFACE TROUGH/AND DEEP CONVECTION DEFINITELY
SUPPORT THIS POTENTIAL. PRIMARY THREAT IS EXPECTED ACROSS THE WATERS
OF LAKE MICHIGAN AND LAKE HURON...WITH THE THREAT ENDING OVERNIGHT
AS THE SURFACE TROUGH PASSES. OTHERWISE...MARGINALLY GUSTY GENERAL
WEST FLOW TODAY...ALTHOUGH BOTH WINDS AND WAVES LOOK TO REMAIN BELOW
SCA CRITERIA. WINDS BEGIN TO PICK UP OUT OF THE SOUTHEAST
SUNDAY...BECOMING QUITE GUSTY SUNDAY NIGHT. WINDS VEER SOUTHWEST ON
MONDAY BEHIND PASSAGE OF A STRONG COLD FRONT. HEADLINES WILL
EVENTUALLY BE NEED FOR THE WATERS LATER SUNDAY RIGHT THROUGH MONDAY
(AND LIKELY BEYOND). MAY EVEN SEE GALE CONDITIONS ON NORTHERN LAKE
MICHIGAN ON MONDAY AS STRONG LOW PRESSURE PULLS UP ACROSS LAKE
SUPERIOR.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.

&&

$$

SYNOPSIS...JZ
SHORT TERM...MB
LONG TERM...JZ
AVIATION...MR
MARINE...MB







AREA FORECAST DISCUSSION

NWS TWIN CITIES/CHANHASSEN MN

 441 PM CDT SAT OCT 19 2013

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 342 PM CDT SAT OCT 19 2013

THE COLD FRONT IS NOW ALMOST COMPLETELY THROUGH MN AND IS
CURRENTLY WORKING ITS WAY ACROSS WEST CENTRAL WI. WE HAD NUMEROUS
REPORTS OF ICE PELLETS TODAY DUE TO THE CONVECTIVE NATURE TO THE
SHOWERS. THIS WAS GRAUPEL GIVEN THE NEAR SURFACE WARM LAYER AND
COLD TEMPS ALOFT. THIS SHOWERY ACTIVITY WILL CONTINUE TO DIMINISH
WITH TIME NOW THAT MN/WI IS POST FRONTAL AND WE ARE LOSING ARE
STEEP LOW LEVEL LAPSE RATES. WE ARE ALREADY SEEING LIGHT BANDED
RAIN IN NORTH CENTRAL ND THIS AFTERNOON IN THE WARM AIR ADVECTION
WING OF THE INCOMING CLIPPER SYSTEM. THIS WILL CONTINUE TO DROP
SOUTHEAST WITH TIME AS THE SYSTEM APPROACHES. KUDOS TO THE NAM FOR
BEING THE TREND SETTER YESTERDAY WITH A MORE SOUTHERLY LOW
TRACK...WHICH IS NOW BEING SHOWN BY THE GEM/ECMWF/GFS. THE 12Z
GUIDANCE TAKES THE LOW ACROSS SOUTHERN MN DURING THE DAY
TOMORROW. THE SOUTHERN SHIFT MEANS AREAS SUCH AS ST. CLOUD...THE
TWIN CITIES...AND EAU CLAIRE WILL END UP WITH A BIT MORE PRECIP
/AT LEAST 0.25"/. THE OVERNIGHT FORECAST MADE LAST NIGHT
RIGHTFULLY BEGAN PULLING THE HIGHER POPS FARTHER SOUTH. THERE IS
STILL A REALLY STRONG FRONOTGENESIS SIGNAL ACROSS CENTRAL MN
BETWEEN 12-18Z TOMORROW. THIS SUGGESTS A QUICK CHANGE OVER TO SNOW
IS LOOKING MORE LIKELY. NOT TO MENTION THAT THE FORECAST SOUNDINGS
SHOW QUICK COLUMN COOLING AT THE ONSET OF PRECIP GIVEN THE LOWER
BL WET BULB TEMPERATURE. 2 TO 4 INCHES SEEMS ENTIRELY POSSIBLE ON
GRASSY AND ELEVATED SURFACES IN THE NORTHERN PORTIONS OF THE
FORECAST AREA. NEAR AND SOUTH OF THE I-94 CORRIDOR WILL STRUGGLE
TO GET A FEW TENTHS GIVEN THE WARMTH OF THE NEAR SURFACE WARM
LAYER.

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 342 PM CDT SAT OCT 19 2013

BY LATE SUNDAY EVENING...THE DRY SLOT OF THE CLIPPER WILL BE
SPREADING ACROSS THE CWA WITH GOOD Q-VECTOR DIVERGENCE. THIS WILL
LIKELY YIELD A DRY NIGHT FOR MOST LOCATIONS SUNDAY NIGHT AND
MONDAY MORNING. THE TROUGH HANGS BACK ACROSS NORTHERN MN ON
MONDAY...SO LIGHT SHOWERS SEEM REASONABLE /AGAIN MAINLY NORTH OF
I-94/. LIGHT SNOW WILL BE THE DOMINATE PRECIP TYPE ON MONDAY. THE
PATTERN REMAINS COOL AND MOSTLY DRY THROUGH THE EXTENDED AFTER THE
WEEKEND...WITH THE LONGWAVE TROUGH BEGINNING TO SHIFT SLIGHTLY EAST
NEAR THE END OF NEXT WEEK OFF THE ECMWF. THE GFS KEEP THE TROUGH
MORE FIRMLY IN PLACE THROUGH THE ENTIRE 240-HR FORECAST...WITH
CONTINUED WELL BELOW NORMAL TEMPERATURES.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 102 PM CDT SAT OCT 19 2013

MVFR CIGS MAY HANG IN THERE THIS AFTERNOON A LITTLE LONGER THAN
PREVIOUSLY THOUGHT. UPPER TROUGH STILL OVER EASTERN MN AND WI AT
MIDDAY. LATEST RAP SHOWS CYCLONIC LOW LEVEL FLOW DOES NOT REALLY
SHIFT EASTWARD ACROSS WESTERN WISCONSIN UNTIL EARLY EVENING. LAMP
HANGS ON A LITTLE LONGER AS WELL...AND SATELLITE TRENDS CERTAINLY
BEAR THIS OUT EVEN IN WEST CENTRAL MN. BUT CELLULAR CU WILL
DISSIPATE AROUND SUNSET. NEXT SYSTEM IN NW FLOW IS QUICK ON ITS
HEELS... WITH MVFR CIGS/VSBYS MOVING INTO WEST CENTRAL MN LATE
TONIGHT. PREVIOUS FORECAST TIMING LOOKS ABOUT RIGHT...THOUGH WILL
ADD SOME DETAIL TO THE ONSET OF PRECIP IN TERMS OF DEVELOPMENT OF MVFR.
KAXN AND KSTC WILL LIKELY SEE IFR CIGS SUNDAY MORNING...CLOSER TO
THE HEAVIER PRECIP...WHERE IT MAY WELL LEAN MORE TO SNOW THAN
RAIN.

KMSP...
MVFR CIGS AROUND 2500 FT AGL WILL REMAIN AROUND KMSP AT LEAST
THROUGH MID AFTERNOON AMID LOW LEVEL CYCLONIC FLOW. WILL NOT BE
SURPRISED IF 2500 FOOT CEILINGS PERSIST UNTIL 23Z OR SO. QUIET
NIGHT WITH BRIEF RIDGE MOVING ACROSS AS LIGHT WINDS SHIFT FROM NW
TO S. NEXT SYSTEM MOVES IN QUICKLY AFTER 12Z...WITH GOOD POTENTIAL
FOR MVFR CEILING/VISIBILITY AROUND 15Z. MIGHT BE SOME WET SNOW
MOVED IN DURING ONSET OF PRECIP TOMORROW...BUT SHOULD GENERALLY BE
RAIN. IT MIGHT END SHORTLY BEFORE 21/00Z BUT NOT SURE YET SO DID
LET IT PERSIST AFTER 15Z AND THROUGH THE BALANCE OF THE FORECAST.

/OUTLOOK FOR KMSP/
MON...VFR WITH -RA/SN POSSIBLE. WINDS NW AT 10G15KT.
TUE...VFR WITH MVFR CIGS POSSIBLE EARLY. WINDS NW AT 10KTS.
WED...VFR WITH MVFR AND -RA/SN POSSIBLE. WINDS SW AT 10KTS.


&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&

$$

SHORT TERM...CLF
LONG TERM...CLF
AVIATION...TDK








AREA FORECAST DISCUSSION

NWS TWIN CITIES/CHANHASSEN MN

 102 PM CDT SAT OCT 19 2013

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CDT SAT OCT 19 2013

A WEAK SURFACE TROUGH WAS LOCATED ACROSS WESTERN MINNESOTA THIS
MORNING...WITH AN EQUALLY WEAK RIDGE OVER THE DAKOTAS. FARTHER
UPSTREAM WINDS WERE OUT OF THE SOUTHEAST IN RESPONSE TO THE
DEVELOPING SYSTEM THAT WILL BRING MEASURABLE SNOW ACROSS THE REGION
LATE TONIGHT INTO SUNDAY MORNING. EARLY MORNING WATER VAPOR
IDENTIFIED THIS SYSTEM OVER NORTHERN BRITISH COLUMBIA. OVER THE NEXT
24 HOURS THIS SHORTWAVE WILL DIVE SOUTHEAST AND EMERGE ACROSS THE
HIGH PLAINS. A CLASSIC LOW LEVEL THERMAL SIGNATURE AT H850 WILL
DEVELOP AHEAD OF THIS WAVE AS IDENTIFIED BY MARTIN ET AL 2007. BROAD
ISENTROPIC ASCENT WILL EVENTUALLY BECOME A FOCUSED REGION OF
VERTICAL MOTION DRIVEN BY H850-700 FGEN. THIS MESOSCALE FORCING WILL
DEVELOP A NARROW BAND OF ACCUMULATING SNOW EXPECTED TO ENTER WESTERN
MINNESOTA LATE SATURDAY NIGHT. THE NAM 19.00 FORECAST SOUNDING
AT SAINT CLOUD SHOWS A VEERING WIND PROFILE...WITH MAX OMEGA IN THE
H800-700 LAYER. THE COBB OUTPUT KEEPS THE MAJORITY OF THE PRECIP AS
LIQUID...AND THEREFORE DOESNT PRODUCE VIRTUALLY ANY SNOW.
HOWEVER...JUST UP THE ROAD AT BRAINERD THE COBB OUTPUT HAS 1.9
INCHES...AND BUFKIT OUTPUT HAS UP TO 4 INCHES. SREF PLUMES SHOW 2
INCHES AT AXN...BUT THESE VALUES ARE LIKELY INFLATED BY A FACTOR OF
TWO DUE TO A FEW OF THE MORE ROBUST RUNS.

MORE OFTEN THAN NOT THE LARGE SCALE MODELS ARE TOO SLOW WITH THE
ONSET...AND DEPARTURE OF THE SNOWFALL WITH THESE CLIPPER SYSTEMS.
THE HIRES RUN OF THE NMM AND ARW EAST SHOW THE PRECIP APPROACHING
THE MN/WI BORDER BY 12Z...SO HAVE INCREASED THE TIMING OF THE POPS.
THE PRECIP SHOULD BE GENERALLY SNOW BEFORE 12Z DUE TO BOTH THE
DIURNAL MINIMUM IN TEMPERATURE...AND THE STRENGTH OF THE FGEN
FORCING. ACCUMULATING SNOW WILL FALL BEYOND THE END OF THIS
PERIOD...BUT STILL HAVE AROUND AN INCH IN THE NORTHWEST CWA BY 12Z
SUNDAY MORNING.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 315 AM CDT SAT OCT 19 2013

MAIN FORECAST CONCERN IS PRECIPITATION TYPE SUNDAY/SUNDAY AFTN AS
THE ONSET OF THE STORM SYSTEM SATURDAY NIGHT...MOVES QUICKLY
ACROSS THE CWA BY THE EARLY EVENING. THE LONGER TERM CONCERN IS
WHETHER ANOTHER ALBERTA CLIPPER TYPE OF SYSTEM BRUSHES OUR REGION
WEDNESDAY.

THE MAIN ISSUE REMAINS THE LOWER 1KM OF THE ATMOSPHERIC THERMAL
PROFILE ONCE THE SYSTEM MOVES ACROSS THE REGION LATE TONIGHT...AND
INTO SUNDAY AFTN. INITIALLY...THE MEAN TEMP OF LOWEST 1KM OF THE
WET-BLUB TEMP ARE CLOSE TO 0C. USUALLY THESE TEMPS ARE A GOOD
CORRELATION BETWEEN WHERE IT SNOWS AND WHERE THE CHANGE OVER
OCCURS TO RAIN. THE MAGIC TEMP IS +1.5C OR LOWER FOR MAINLY SNOW.

OVERALL ALL MODELS INITIALLY HAVE THIS TEMP NEAR OR SLIGHTLY BLW
0C AFT MIDNIGHT TONIGHT WHICH MEANS THAT ONCE PRECIPITATION
BEGINS...IT SHOULD BE IN THE FORM OF SNOW. ONLY THE FAR WEST/SW
CWA HAS A CHC OF RAIN OR A MIXTURE OF RAIN/SNOW DUE TO SLIGHTLY
HIGHER TEMPS IN THE LOWEST 1KM. THESE TEMPS QUICKLY RISE AS STRONG
WAA DEVELOPS BY 12Z SUNDAY. BY 18Z SUNDAY...MOST AREAS RISE ABV
THE +1.5C TEMP...WITH ONLY PORTIONS OF CENTRAL MN AND WC WI HAVING
TEMPS CLOSE TO 2C. WITH THIS IN MIND...WILL CONTINUE WITH A
RAIN/SNOW MIXTURE DURING THE MORNING /POSSIBLY ALL SNOW INITIALLY
IN CENTRAL EC MN/...THEN QUICKLY CHANGING TO EITHER ALL RAIN...OR
A MIXTURE OF RAIN/SNOW BY LATE SUNDAY MORNING/EARLY AFTN. AS
DISCUSS PREVIOUSLY...THIS SYSTEM IS FAST WHICH WILL TAKE THE BULK
OF THE PRECIPITATION OUT OF MN BY THE MID/LATE AFTN OF SUNDAY. THE
BEST LOCATION OF REMAINING ALL SNOW WILL OCCUR NORTH OF A LITTLE
FALLS TO MORA TO RUSH CITY LINE IN MINNESOTA...AND NORTH OF A LUCK
TO RICE LAKE TO LADYSMITH LINE IN WISCONSIN. AN INCH OR TWO OF
HEAVY WET SNOW IS POSSIBLE IN THESE AREAS. DUE TO THE WARM
GROUND...MOST OF THE SNOW WILL ONLY ACCUMULATE ON GRASSY SURFACES
AND TREES.

AFTER SUNDAY...THICKNESS VALUES WILL REMAIN COLD ENOUGH FOR MAINLY
SNOW OR SNOW SHOWERS...WITH ONLY A SLIGHT CHANCE OF MIXING WITH
RAIN SHOWERS DURING THE DAYTIME HOURS. ANY SYSTEM THAT MOVES
ACROSS THE AREA NEXT WEEK IS RATHER WEAK COMPARED TO SUNDAY/S
WHICH WILL LEAD TO LITTLE OR NO SNOWFALL ACCUMULATIONS. NEXT WEEK
WILL REMAIN WELL BLW NORMAL WITH ONLY A SLIGHT MODIFICATION BY
LATE IN THE WEEK AND INTO NEXT WEEKEND.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 102 PM CDT SAT OCT 19 2013

MVFR CIGS MAY HANG IN THERE THIS AFTERNOON A LITTLE LONGER THAN
PREVIOUSLY THOUGHT. UPPER TROUGH STILL OVER EASTERN MN AND WI AT
MIDDAY. LATEST RAP SHOWS CYCLONIC LOW LEVEL FLOW DOES NOT REALLY
SHIFT EASTWARD ACROSS WESTERN WISCONSIN UNTIL EARLY EVENING. LAMP
HANGS ON A LITTLE LONGER AS WELL...AND SATELLITE TRENDS CERTAINLY
BEAR THIS OUT EVEN IN WEST CENTRAL MN. BUT CELLULAR CU WILL
DISSIPATE AROUND SUNSET. NEXT SYSTEM IN NW FLOW IS QUICK ON ITS
HEELS... WITH MVFR CIGS/VSBYS MOVING INTO WEST CENTRAL MN LATE
TONIGHT. PREVIOUS FORECAST TIMING LOOKS ABOUT RIGHT...THOUGH WILL
ADD SOME DETAIL TO THE ONSET OF PRECIP IN TERMS OF DEVELOPMENT OF MVFR.
KAXN AND KSTC WILL LIKELY SEE IFR CIGS SUNDAY MORNING...CLOSER TO
THE HEAVIER PRECIP...WHERE IT MAY WELL LEAN MORE TO SNOW THAN
RAIN.

KMSP...
MVFR CIGS AROUND 2500 FT AGL WILL REMAIN AROUND KMSP AT LEAST
THROUGH MID AFTERNOON AMID LOW LEVEL CYCLONIC FLOW. WILL NOT BE
SURPRISED IF 2500 FOOT CEILINGS PERSIST UNTIL 23Z OR SO. QUIET
NIGHT WITH BRIEF RIDGE MOVING ACROSS AS LIGHT WINDS SHIFT FROM NW
TO S. NEXT SYSTEM MOVES IN QUICKLY AFTER 12Z...WITH GOOD POTENTIAL
FOR MVFR CEILING/VISIBILITY AROUND 15Z. MIGHT BE SOME WET SNOW
MOVED IN DURING ONSET OF PRECIP TOMORROW...BUT SHOULD GENERALLY BE
RAIN. IT MIGHT END SHORTLY BEFORE 21/00Z BUT NOT SURE YET SO DID
LET IT PERSIST AFTER 15Z AND THROUGH THE BALANCE OF THE FORECAST.

/OUTLOOK FOR KMSP/
MON...VFR WITH -RA/SN POSSIBLE. WINDS NW AT 10G15KT.
TUE...VFR WITH MVFR CIGS POSSIBLE EARLY. WINDS NW AT 10KTS.
WED...VFR WITH MVFR AND -RA/SN POSSIBLE. WINDS SW AT 10KTS.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&

$$

SHORT TERM...JRB
LONG TERM...JLT
AVIATION...TDK







AREA FORECAST DISCUSSION

NWS KANSAS CITY/PLEASANT HILL MO

 1201 AM CDT Sat Oct 19 2013

.UPDATE...
Issued at 949 PM CDT FRI OCT 18 2013

The going forecast remains on track and only minor changes were made
to temperatures and PoPs to keep up with trends in each. Potential
remains for some patchy frost tonight but there are a few things
that may hinder development despite temperatures falling into the
32-35 degree range across most of the area. The biggest is that it
looks like winds will not be calm and generally be around 5 mph or
so, with the exception of some very sheltered areas. The other is
that there is some uncertainty with how much cloud cover will be
present in the area. Some recent runs of short-term models including
the RAP and HRRR start to develop and/or move lower clouds back into
the area late tonight. Latest fog imagery is showing an area of IFR
stratus forming over eastern KS as the higher level clouds move out.
Short-range models drift this area east through overnight,
encompassing most of western Missouri through the better part of the
overnight. These two factors negatively impact the radiational
cooling potential and thus potential for frost. Will continue to
monitor trends but at this time widespread frost does not seem
likely.

&&

.SHORT TERM...(This Evening through Sunday Night)
Issued at 331 PM CDT FRI OCT 18 2013

For this evening, the main concern will be moderate rain moving
through the southern two thirds of the forecast area in advance of a
southeastward moving shortwave trough. A dry boundary layer and cold
temperatures aloft have allowed a few pellets of sleet to mix with
rain especially as the column initially saturates, and has also
allowed a few flakes of snow to mix with the lighter rain on the
back side of the precipitation shield. Rainfall amounts should be
around a few tenths to a quarter of an inch, and no accumulation of
wintry precipitation is expected. As frontogenesis weakens late this
afternoon into the early evening, precipitation should lighten
considerably and may start to break up a bit as it heads southeast.

After the precipitation clears out during the late evening to early
overnight hours, temperatures and frost potential will be the main
concern. The degree of clearing will be uncertain with additional
clouds working down across Iowa and portions of northern Missouri,
and non-zero surface winds will also make cooling of the ground
layer a bit more difficult, so have held off on a frost advisory for
now. However, temperatures will not have to fall far to get into the
lower to mid 30s since readings have fallen into the upper 30s
across many areas currently experiencing precipitation, so some
precaution will be needed with sensitive vegetation tonight.

Temperatures will slowly recover on Saturday, then will be much
warmer on Sunday as breezy west winds and sunshine help highs climb
into the upper 60s to even lower 70s. Lows should not be a concern
on Sunday or Monday mornings, with better moisture and southerly
winds helping temperatures stay in the upper 30s to mid 40s both
nights. No additional precipitation is expected through Sunday night.

.LONG TERM...(Monday through Friday)
Issued at 349 PM CDT FRI OCT 18 2013

Medium range models maintain a cold pattern during most of the
period as the mean upper trough over the eastern half of the nation
gradually shifts east. A couple of fast moving clipper type systems
are expected to zip down the back side of the upper trough with the
initial one possibly affecting the CWA on Tuesday. The 12z GFS came
into agreement with the 00z ECMWF but now the 12z ECMWF tracks the
clipper further east. Enough uncertainty due to model waffling that
30-40% PoPs are high enough. Cold air advection through Monday night
in previous forecasts called into the possibility of freezing
temperatures is somewhat mitigated due to the expected increase in
cloud cover. So, have raised overnight lows for Monday night.

Latest ECMWF shows stronger cold air advection behind Tuesday system
for Wednesday but believe that is overdone. Nonetheless, the
overriding theme from Wednesday on is well below average
temperatures. A continued northerly component of the boundary layer
winds will funnel the shallow cold air from the Canadian provinces
southward despite rising heights aloft.

&&

.AVIATION...(For the 06Z TAFS through 06Z Saturday Night)
Issued at 1155 PM CDT FRI OCT 18 2013

Low IFR stratus has expanded over eastern Kansas and western
Missouri. This is eroding from the west but it looks to be affecting
the terminals through the overnight hours. Have persisted the IFR
ceilings through about 12Z. Some model guidance suggest ceilings
lifting/moving away earlier. But the latest short-range models
persist IFR ceilings through sunrise over far western Missouri.
Confidence is only medium on the timing of the ending of the IFR
conditions. Once ceilings lift, in the morning, VFR conditions
should prevail with winds becoming gusty from west- northwest. Winds
will taper off towards sunset with skies becoming clear.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&

$$

UPDATE...CDB
SHORT TERM...Laflin
LONG TERM...MJ
AVIATION...CDB







AREA FORECAST DISCUSSION

NWS BURLINGTON VT

 748 PM EDT SUN OCT 20 2013

.SYNOPSIS...
WHILE STARTING OUT RELATIVELY MILD ON MONDAY...THE WEATHER THIS WEEK
ACROSS THE NORTH COUNTRY WILL TURN MUCH COOLER WITH SEVERAL
CHANCES FOR SOME LIGHT RAIN AND EVEN SOME MOUNTAIN SNOW SHOWERS.
THE GREATEST CHANCE FOR WIDESPREAD RAIN SHOWERS WILL COME MONDAY
NIGHT INTO TUESDAY AS A COLD FRONT PASSES THROUGH THE REGION
USHERING IN THE COOLER AIR.

&&

.NEAR TERM /UNTIL 8 AM MONDAY MORNING/...
AS OF 707 PM EDT SUNDAY...INFRARED SATELLITE REVEALS A PLUME OF LAKE
EFFECT CLOUDINESS AFFECTING CENTRAL AND WESTERN NEW YORK.
MEANWHILE FURTHER BACK TO THE WEST...BROAD SHIELD OF MID- LEVEL
CLOUDINESS TIED TO A SFC WARM FRONT BEGINNING TO QUICKLY APPROACH
SOUTHWESTERN ONTARIO. REGIONAL VWP AND RAP ANALYSIS DATA ACROSS
WESTERN NEW YORK STATE SHOWING LOW-LEVEL FLOW BACKING TO
SOUTHWEST. THE GENERAL IDEA IS THAT INCREASING WARM AIR ADVECTION
SHOULD BE BEGINNING OVER THE NEXT COUPLE OF HOURS ACROSS THE SAINT
LAWRENCE VALLEY AND THE ADIRONDACKS...WITH AN INCREASE IN CLOUDS
AND SLIGHTLY WARMER LOW TEMPS. I SUSPECT IT`LL BE COLDER IN
EASTERN VERMONT AND THE NORTHEAST KINGDOM WHERE THE LOW- LEVEL
WARM ADVECTION AND ASSOCIATED CLOUDINESS WILL TAKE LONGER TO
OVERSPREAD...MOST LIKELY NOT UNTIL THE EARLY MORNING. SO I`VE
STARTED TO RAISE MIN TEMPERATURES UP A FEW DEGREES ACROSS NORTHERN
NEW YORK AND THE NORTHERN ADIRONDACKS. I`VE ALSO REMOVED MENTION
OF SLIGHT CHANCE OF LAKE EFFECT SHOWERS IN THE ADIRONDACKS. WITH
LOW-LEVEL WINDS BEGINNING TO BACK TO SOUTHWEST...THINK ANY LAKE
EFFECT SHOWERS WILL REMAIN TO THE SOUTH AND WEST.

&&

.SHORT TERM /8 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
AS OF 308 PM EDT SUNDAY...WARM FRONT PASSES ACROSS THE NORTH
COUNTRY MONDAY MORNING AS SOUTHWESTERLY FLOW STRENGTHENS AHEAD OF
THE NEXT LOW PRESSURE SYSTEM MOVING THROUGH THE GREAT LAKES. THIS
WILL PLACE THE REGION IN THE WARM SECTOR...SO HIGHS WILL BE ABOVE
NORMAL...IN THE UPPER 50S AND LOWER 60S. AN AREA OF CLOUDS WILL
MOVE ACROSS VT/NY IN THE MORNING WITH THE WARM FRONT...BUT REST
OF THE DAY SHOULD FEATURE PARTLY-MOSTLY SUNNY SKIES IN EASTERN AND
SOUTHERN VERMONT AND MOSTLY CLOUDY SKIES ACROSS NORTHERN NEW YORK
CLOSER TO THE APPROACHING LOW...WITH FILTERED SUNSHINE IN THE
CHAMPLAIN VALLEY AND WESTERN VERMONT. SOUTH WINDS WILL BE ON THE
INCREASE WITH GUSTS UP TO 25 MPH.

SOUTHWEST FLOW ALOFT INTENSIFIES FURTHER MONDAY NIGHT AS THE LOW
PRESSURE SYSTEM APPROACHES. HOWEVER...MAIN LOW WILL STAY WELL NORTH
OF THE AREA...DRAGGING A COLD FRONT INTO THE REGION TOWARDS TUESDAY
MORNING. THIS WILL BRING A BAND OF RAIN SHOWERS THAT WILL MOVE
THROUGH THE NORTH COUNTRY LATER MONDAY NIGHT AND INTO TUESDAY. LIKE
PREVIOUS SYSTEMS...AMOUNTS WILL BE LIGHT...A TENTH TO A QUARTER
OF AN INCH TOPS. TEMPERATURES WILL STAY RELATIVELY MILD AHEAD OF
THE FRONT SO LOWS MONDAY NIGHT WILL ONLY DROP INTO THE 40S TO NEAR
50...BUT THEN NOT GO VERY FAR ON TUESDAY POST-FRONTAL WITH HIGHS
IN THE UPPER 40S TO MID 50S.

WEST-SOUTHWEST FLOW DEVELOPS BEHIND THE COLD FRONT LATER TUESDAY AND
TUESDAY NIGHT...KEEPING SOME CLOUDS ACROSS THE REGION AND THE CHANCE
FOR SOME LAKE EFFECT RAIN AND HIGHER TERRAIN SNOW SHOWERS IN
NORTHERN NEW YORK. LOWS LOOK TO BE NEAR NORMAL...GENERALLY IN THE
30S (40S ALONG LAKE CHAMPLAIN) WITH PERHAPS SOME 20S IN THE
ADIRONDACKS.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 439 AM EDT SUNDAY...ECMWF AND GFS DEPICT DEEPENING TROUGH OVER
THE OHIO VALLEY WEDNESDAY...WHICH RESULTS IN DEVELOPMENT OF WEAK
SURFACE LOW OFF MID ATLANTIC COAST. THIS LOW THEN DEEPENS AND
HEADS RAPIDLY NORTHEAST...PASSING NEAR 40N 70W LATE WEDNESDAY AND
THEN TO NOVA SCOTIA WEDNESDAY NIGHT. PRECIPITATION ASSOCIATED WITH
THIS SYSTEM EXPECTED TO REMAIN SOUTHEAST OF FORECAST AREA. BUT
THERE WILL BE A LOW CHANCE FOR SHOWERS DURING THIS PERIOD AS
MODELS INDICATE THAT SOME LAKE EFFECT MOISTURE FROM LAKE ONTARIO
WILL BE PULLED NORTHEAST INTO NORTHERN NEW YORK AND VERMONT. HAVE
CONTINUED WITH SLIGHT CHANCE OR CHANCE POPS FOR SHOWERS WEDNESDAY
INTO WEDNESDAY NIGHT...WITH HIGHEST POPS OVER ADIRONDACKS. UPPER
TROUGH REMAINS OVER THE NORTHEAST THURSDAY/FRIDAY WITH FORECAST
AREA UNDER CYCLONIC NORTHWESTERLY FLOW WITH GRADUAL COLD AIR
ADVECTION CONTINUING. THE RESULT WILL BE A LOT OF CLOUDS AND THE
CHANCE FOR SOME MOUNTAIN SNOW/RAIN SHOWERS...WHILE VALLEYS REMAIN
MOSTLY DRY...WITH ONLY LOW CHANCE FEW LIGHT RAIN SHOWERS. HIGH
PRESSURE BUILDS IN FROM THE EASTERN GREAT LAKES LATER
FRIDAY...BRINGING DRY CONDITIONS TO THE FORECAST AREA FRIDAY NIGHT
INTO SATURDAY MORNING. CHANCES FOR SHOWERS THEN INCREASE SATURDAY
AFTERNOON INTO SUNDAY AS UPPER TROUGH AND ASSOCIATED SURFACE LOW
APPROACH FROM THE GREAT LAKES.

BELOW NORMAL TEMPERATURES ARE EXPECTED FOR MUCH OF THE EXTENDED
PERIOD WITH HIGHS MAINLY IN THE 40S WITH 30S IN THE MOUNTAINS. LOWS
WILL GENERALLY RANGE FROM THE MID 20S TO MID 30S. TEMPERATURES WARM
A BIT BACK TO SEASONABLE LEVELS NEXT WEEKEND.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
THROUGH 00Z TUESDAY...VFR CONDITIONS EXPECTED THROUGH THE PERIOD.
LOOK FOR AN AREA OF CLOUDS...VFR CEILINGS...TO MOVE FROM SOUTHWEST
TO NORTHEAST ACROSS THE AREA BETWEEN 02Z AND 12Z BEFORE MOVING
NORTHEAST OF THE AREA. WINDS WILL GENERALLY BE LIGHT AND VARIABLE
THROUGH THIS PERIOD. AFTER 12Z...LOOK FOR INCREASING SOUTH TO
SOUTHWEST WINDS WITH GUSTS IN THE 15 TO 25 KNOT RANGE AFTER 15Z
AND CONTINUING THROUGH THE PERIOD. ANY CEILINGS DURING THIS TIME
PERIOD WILL BE ABOVE 8000 FEET. VFR VISIBILITIES ARE EXPECTED
THROUGH THE ENTIRE PERIOD.

OUTLOOK 00Z TUESDAY THROUGH FRIDAY...

00Z TUESDAY THROUGH 00Z WEDNESDAY...PERIODS OF MVFR IN SHOWERS AS
COLD FRONT MOVES THROUGH.

00Z WEDNESDAY ONWARD...MAINLY VFR WITH SOME MVFR POSSIBLE AT TIMES
IN SCATTERED SHOWERS...ESPECIALLY AT SLK/MPV. PSBL -SHSN AT SLK.

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.

&&

$$
SYNOPSIS...MUCCILLI
NEAR TERM...LOCONTO/MUCCILLI
SHORT TERM...MUCCILLI
LONG TERM...RJS
AVIATION...EVENSON/RJS






AREA FORECAST DISCUSSION

NWS BURLINGTON VT

 707 PM EDT SUN OCT 20 2013

.SYNOPSIS...
WHILE STARTING OUT RELATIVELY MILD ON MONDAY...THE WEATHER THIS WEEK
ACROSS THE NORTH COUNTRY WILL TURN MUCH COOLER WITH SEVERAL
CHANCES FOR SOME LIGHT RAIN AND EVEN SOME MOUNTAIN SNOW SHOWERS.
THE GREATEST CHANCE FOR WIDESPREAD RAIN SHOWERS WILL COME MONDAY
NIGHT INTO TUESDAY AS A COLD FRONT PASSES THROUGH THE REGION
USHERING IN THE COOLER AIR.

&&

.NEAR TERM /UNTIL 8 AM MONDAY MORNING/...
AS OF 707 PM EDT SUNDAY...INFRARED SATELLITE REVEALS A PLUME OF LAKE
EFFECT CLOUDINESS AFFECTING CENTRAL AND WESTERN NEW YORK.
MEANWHILE FURTHER BACK TO THE WEST...BROAD SHIELD OF MID- LEVEL
CLOUDINESS TIED TO A SFC WARM FRONT BEGINNING TO QUICKLY APPROACH
SOUTHWESTERN ONTARIO. REGIONAL VWP AND RAP ANALYSIS DATA ACROSS
WESTERN NEW YORK STATE SHOWING LOW-LEVEL FLOW BACKING TO
SOUTHWEST. THE GENERAL IDEA IS THAT INCREASING WARM AIR ADVECTION
SHOULD BE BEGINNING OVER THE NEXT COUPLE OF HOURS ACROSS THE SAINT
LAWRENCE VALLEY AND THE ADIRONDACKS...WITH AN INCREASE IN CLOUDS
AND SLIGHTLY WARMER LOW TEMPS. I SUSPECT IT`LL BE COLDER IN
EASTERN VERMONT AND THE NORTHEAST KINGDOM WHERE THE LOW- LEVEL
WARM ADVECTION AND ASSOCIATED CLOUDINESS WILL TAKE LONGER TO
OVERSPREAD...MOST LIKELY NOT UNTIL THE EARLY MORNING. SO I`VE
STARTED TO RAISE MIN TEMPERATURES UP A FEW DEGREES ACROSS NORTHERN
NEW YORK AND THE NORTHERN ADIRONDACKS. I`VE ALSO REMOVED MENTION
OF SLIGHT CHANCE OF LAKE EFFECT SHOWERS IN THE ADIRONDACKS. WITH
LOW-LEVEL WINDS BEGINNING TO BACK TO SOUTHWEST...THINK ANY LAKE
EFFECT SHOWERS WILL REMAIN TO THE SOUTH AND WEST.

&&

.SHORT TERM /8 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
AS OF 308 PM EDT SUNDAY...WARM FRONT PASSES ACROSS THE NORTH
COUNTRY MONDAY MORNING AS SOUTHWESTERLY FLOW STRENGTHENS AHEAD OF
THE NEXT LOW PRESSURE SYSTEM MOVING THROUGH THE GREAT LAKES. THIS
WILL PLACE THE REGION IN THE WARM SECTOR...SO HIGHS WILL BE ABOVE
NORMAL...IN THE UPPER 50S AND LOWER 60S. AN AREA OF CLOUDS WILL
MOVE ACROSS VT/NY IN THE MORNING WITH THE WARM FRONT...BUT REST
OF THE DAY SHOULD FEATURE PARTLY-MOSTLY SUNNY SKIES IN EASTERN AND
SOUTHERN VERMONT AND MOSTLY CLOUDY SKIES ACROSS NORTHERN NEW YORK
CLOSER TO THE APPROACHING LOW...WITH FILTERED SUNSHINE IN THE
CHAMPLAIN VALLEY AND WESTERN VERMONT. SOUTH WINDS WILL BE ON THE
INCREASE WITH GUSTS UP TO 25 MPH.

SOUTHWEST FLOW ALOFT INTENSIFIES FURTHER MONDAY NIGHT AS THE LOW
PRESSURE SYSTEM APPROACHES. HOWEVER...MAIN LOW WILL STAY WELL NORTH
OF THE AREA...DRAGGING A COLD FRONT INTO THE REGION TOWARDS TUESDAY
MORNING. THIS WILL BRING A BAND OF RAIN SHOWERS THAT WILL MOVE
THROUGH THE NORTH COUNTRY LATER MONDAY NIGHT AND INTO TUESDAY. LIKE
PREVIOUS SYSTEMS...AMOUNTS WILL BE LIGHT...A TENTH TO A QUARTER
OF AN INCH TOPS. TEMPERATURES WILL STAY RELATIVELY MILD AHEAD OF
THE FRONT SO LOWS MONDAY NIGHT WILL ONLY DROP INTO THE 40S TO NEAR
50...BUT THEN NOT GO VERY FAR ON TUESDAY POST-FRONTAL WITH HIGHS
IN THE UPPER 40S TO MID 50S.

WEST-SOUTHWEST FLOW DEVELOPS BEHIND THE COLD FRONT LATER TUESDAY AND
TUESDAY NIGHT...KEEPING SOME CLOUDS ACROSS THE REGION AND THE CHANCE
FOR SOME LAKE EFFECT RAIN AND HIGHER TERRAIN SNOW SHOWERS IN
NORTHERN NEW YORK. LOWS LOOK TO BE NEAR NORMAL...GENERALLY IN THE
30S (40S ALONG LAKE CHAMPLAIN) WITH PERHAPS SOME 20S IN THE
ADIRONDACKS.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 439 AM EDT SUNDAY...ECMWF AND GFS DEPICT DEEPENING TROUGH OVER
THE OHIO VALLEY WEDNESDAY...WHICH RESULTS IN DEVELOPMENT OF WEAK
SURFACE LOW OFF MID ATLANTIC COAST. THIS LOW THEN DEEPENS AND
HEADS RAPIDLY NORTHEAST...PASSING NEAR 40N 70W LATE WEDNESDAY AND
THEN TO NOVA SCOTIA WEDNESDAY NIGHT. PRECIPITATION ASSOCIATED WITH
THIS SYSTEM EXPECTED TO REMAIN SOUTHEAST OF FORECAST AREA. BUT
THERE WILL BE A LOW CHANCE FOR SHOWERS DURING THIS PERIOD AS
MODELS INDICATE THAT SOME LAKE EFFECT MOISTURE FROM LAKE ONTARIO
WILL BE PULLED NORTHEAST INTO NORTHERN NEW YORK AND VERMONT. HAVE
CONTINUED WITH SLIGHT CHANCE OR CHANCE POPS FOR SHOWERS WEDNESDAY
INTO WEDNESDAY NIGHT...WITH HIGHEST POPS OVER ADIRONDACKS. UPPER
TROUGH REMAINS OVER THE NORTHEAST THURSDAY/FRIDAY WITH FORECAST
AREA UNDER CYCLONIC NORTHWESTERLY FLOW WITH GRADUAL COLD AIR
ADVECTION CONTINUING. THE RESULT WILL BE A LOT OF CLOUDS AND THE
CHANCE FOR SOME MOUNTAIN SNOW/RAIN SHOWERS...WHILE VALLEYS REMAIN
MOSTLY DRY...WITH ONLY LOW CHANCE FEW LIGHT RAIN SHOWERS. HIGH
PRESSURE BUILDS IN FROM THE EASTERN GREAT LAKES LATER
FRIDAY...BRINGING DRY CONDITIONS TO THE FORECAST AREA FRIDAY NIGHT
INTO SATURDAY MORNING. CHANCES FOR SHOWERS THEN INCREASE SATURDAY
AFTERNOON INTO SUNDAY AS UPPER TROUGH AND ASSOCIATED SURFACE LOW
APPROACH FROM THE GREAT LAKES.

BELOW NORMAL TEMPERATURES ARE EXPECTED FOR MUCH OF THE EXTENDED
PERIOD WITH HIGHS MAINLY IN THE 40S WITH 30S IN THE MOUNTAINS. LOWS
WILL GENERALLY RANGE FROM THE MID 20S TO MID 30S. TEMPERATURES WARM
A BIT BACK TO SEASONABLE LEVELS NEXT WEEKEND.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
THROUGH 18Z MONDAY...MAINLY VFR CONDITIONS EXPECTED THROUGH THE
PERIOD AS HIGH PRESSURE MOVES EAST ACROSS THE REGION.

DRIER AIR CONTINUES TO WORK INTO REGION WITH APPROACH OF HIGH
PRESSURE. SATELLITE LOOP AND SURFACE OBSERVATIONS INDICATE BROKEN
DECK OF STRATOCUMULUS CLOUDS ACROSS THE REGION AT THIS TIME WITH
CIGS MAINLY ABOVE 4000 FT. EXPECT DIMINISHING CLOUDS LATER THIS
AFTERNOON/EVENING WITH LOSS OF ANY DAYTIME HEATING. EXCEPTION WILL
BE DOWNWIND OF LAKE ONTARIO WHERE CLOUDS WILL PERSIST...AND MAY
AFFECT SLK WITH A PERIOD OF MVFR LATE TONIGHT. OTHERWISE...MAINLY
CLEAR SKIES TONIGHT WILL GIVE WAY TO SOME BROKEN MID LEVEL CLOUDS
BY MORNING WITH ONSET OF WARM AIR ADVECTION.

WINDS WILL BE WESTERLY 10-15 KTS WITH GUSTS 20-25 KTS THIS
AFTERNOON. WINDS WILL DIMINISH THIS EVENING AND THEN INCREASE FROM
THE SSW TO 8-15 KTS MONDAY.

OUTLOOK 18Z MONDAY THROUGH FRIDAY...

18Z MONDAY THROUGH 00Z TUESDAY...VFR UNDER DEPARTING HIGH PRESSURE.

00Z TUESDAY THROUGH 00Z WEDNESDAY...PERIODS OF MVFR IN SHOWERS
AS COLD FRONT MOVES THROUGH.

00Z WEDNESDAY ONWARD...MAINLY VFR WITH SOME MVFR POSSIBLE AT TIMES
IN SCATTERED SHOWERS...ESPECIALLY AT SLK/MPV. PSBL -SHSN AT SLK.

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.

&&

$$
SYNOPSIS...MUCCILLI
NEAR TERM...LOCONTO/MUCCILLI
SHORT TERM...MUCCILLI
LONG TERM...RJS
AVIATION...RJS











AREA FORECAST DISCUSSION...COR

NWS WILMINGTON NC

 600 PM EDT SAT OCT 19 2013

.SYNOPSIS...
A LINGERING COLD FRONT OVER THE COASTAL CAROLINAS WILL MOVE OFF
SHORE AS HIGH PRESSURE BUILDS IN THROUGH SUNDAY. THE FRONT WILL
SHIFT BACK TOWARD THE COAST AS HIGH PRESSURE MOVES OFF TO THE
NORTHEAST LATE MONDAY INTO TUESDAY. COLDER HIGH PRESSURE WILL
SLOWLY BUILD INTO THE AREA MID THROUGH LATE OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 6 PM SATURDAY...THE LATEST RADAR TRENDS SUGGEST FAVORABLE
DYNAMICS ALOFT ARE BEGINNING TO PLAY A ROLE IN THE UPTREND IN
SHOWER ACTIVITY PRESENTLY. AN UPPER JET CROSSING THE APPALACHIANS
IS PRODUCING A ZONE OF DIFFLUENCE ALOFT OVER CENTRAL CAROLINAS
WHICH IS GRADUALLY EDGING EASTWARD. INITIALLY HIGHER POP VALUES
THIS EVENING ARE PLACED ACROSS OUR WESTERN ZONES...SPREADING OVER
MUCH OF THE FORECAST AREA OVERNIGHT. INSTABILITY OVER THE REGION
REMAINS WEAK AND PRECIPITABLE WATERS HIGH...SO WILL MAINTAIN A
MENTION OF ISOLATED SHOWERS THROUGH 12Z SUNDAY. THE LATEST NAM
MODEL RUN DEPICTS EXPANDING STRATIFORM RAIN OVER THE EASTERN
CAROLINAS AFTER 6Z/2AM TONIGHT INTO DAYBREAK SUNDAY...AS MOISTURE
ALOFT FROM THE SW OVER-RUNS THE LEADING EDGE OF BUILDING HIGH
PRESSURE AND NORTHERLY WIND FLOW IN THE LOW-LEVELS. THIS IS
FEASIBLE AND THE ISENTROPIC OMEGA WOULD HELP SATURATE THE LOW AND
MID LEVELS. WITH THIS IN MIND WE MAY NEED TO BRING POP VALUES UP
WITH THE MID EVENING UPDATE FOR THE DAYBREAK SUNDAY TIME FRAME.
WILL ALSO NEED TO TAKE A CLOSER LOOK AT MINIMUMS FOR DAYBREAK
SUNDAY AS THE RUC UPDATES SUGGEST OVERNIGHT WILL REMAIN MILDER
THAN FORECAST WITH CLOUDS AND POTENTIAL STRATIFORM RAIN IN THE
PRE-DAWN HOURS.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
AS OF 3 PM SATURDAY...COLD FRONT WILL SHIFT SLIGHTLY FURTHER
SOUTH AND EAST OFF THE COAST THROUGH SUNDAY AS HIGH PRESSURE
BUILDS IN BEHIND IT. THIS WILL ALLOW AREA TO DRY OUT THROUGH
SUNDAY. LOOKS LIKE DRYING OUT MAY BE SLOWER THAN PREVIOUS THOUGHT
WITH INCREASING SUNSHINE THROUGH THE LATE MORNING INTO EARLY
AFTERNOON FROM WEST TO EAST ACROSS FORECAST AREA. STILL A
DISCREPANCY OF 5 TO 10 DEGREES BETWEEN NAM AND MAV GUIDANCE FOR
DEWPOINT TEMPS SUNDAY AFTERNOON WITH THE NAM BEING DRIER. EITHER
WAY...SUNDAY LOOKS TO BE SHAPING UP TO BE A NICE FALL-LIKE DAY
WITH A GOOD DEAL OF AFTERNOON SUNSHINE.

THE HIGH PRESSURE WILL SLIP OFF THE DELMARVA COAST BY MONDAY
MORNING ALLOWING THIS LINGERING FRONT TO SHIFT BACK TOWARD THE
COAST PLAGUING THE AREA WITH CLOUDS AND PCP ONCE AGAIN. COASTAL
SECTIONS MAY BE INTO THE CLOUDS BY DAYBREAK BUT THE CLOUDS AND PCP
WILL SPREAD BACK TOWARD THE NORTH. PERTURBATIONS IN THE SOUTHWEST
FLOW ALOFT WILL AID IN GENERATING CLOUDS AND A WAVE OF LOW
PRESSURE AT THE SURFACE WILL ALSO MOVE ALONG THE BOUNDARY FROM
SOUTHWEST TO NORTHEAST INCREASING PCP CHANCES BY LATE MONDAY NIGHT.
EXPECT MORE IN THE WAY OF CLOUDS THROUGH MONDAY WITH LIGHT PCP
MAINLY OFF SHORE AND CLOSE TO THE COAST BY LATE DAY AND BETTER CHC
OF MEASURABLE PCP OVERNIGHT MONDAY.

COOL AND DRY AIR ADVECTION THROUGH SUNDAY WILL KEEP DAY TIME HIGHS
CLOSER TO 70 AND OVERNIGHT LOWS WILL DROP OUT IN MORE IDEAL
RADIATIONAL COOLING CONDITIONS. CLOUDS TOWARD DAYBREAK COULD
HAMPER TEMP FALLS BUT FOR NOW WILL KEEP WITH READINGS BETWEEN 45
AND 50 MOST PLACES. CLOUDS WILL KEEP TMPS SLIGHTLY COOLER ON
MONDAY ONCE AGAIN AND WARMER OVERNIGHT WITH READINGS IN THE MID
TO UPPER 50S BY MONDAY NIGHT.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 300 PM SATURDAY...UNSETTLED WEATHER TO BEGIN THE PERIOD...BUT
THE STORY OF THE EXTENDED WILL FOCUS PRIMARILY ON THE COLD OUTBREAK
EXPECTED FOR THE END OF THE WEEK.

BROAD MID-LEVEL TROUGHING BEGINS TO SHARPEN AT THE START OF THE
PERIOD...BUT THE TROUGH AXIS REMAINS WEST OF THE LOCAL AREA ON
TUESDAY. THIS DRIVES MOIST SW FLOW THROUGH MUCH OF THE
COLUMN...WHICH IS TAPPED BY WEAK WAVES OF LOW PRESSURE WHICH WILL
MOVE ALONG A STALLED BOUNDARY JUST OFF THE SE COAST. THESE WILL WORK
TOGETHER TO CREATE DECENT PRECIP CHANCES TUESDAY. ONLY LIGHT RAIN IS
EXPECTED WITH .1 TO .25 QPF LIKELY...HIGHEST ALONG THE
COAST...BEFORE DRYING BEGINS LATE TUESDAY NIGHT AS SOME NVA DEVELOPS
ALOFT AND SURFACE FLOW VEERS TO THE W/NW.

THE REST OF THE PERIOD WILL BE DRY...BUT THE COOLEST AIR OF THE
SEASON IS EXPECTED TO FLOOD INTO THE CAROLINAS BEGINNING THURSDAY.
WEDNESDAY WILL BE A TRANSITIONAL DAY WITH DRYING OCCURRING...BUT CAA
DELAYED UNTIL LATE AS THE UPPER TROUGH AXIS MOVES EAST OF THE AREA.
WHILE THIS HAPPENS...STRONG CYCLOGENESIS OCCURS OFF THE NEW ENGLAND
COAST...WHICH DRIVES THE SECONDARY COLD FRONT OVER THE AREA AND
HELPS STRONG CAA DEVELOP IN ADVANCE OF A CANADIAN HIGH SINKING SOUTH
ACROSS THE CENTRAL PLAINS. THIS HIGH WILL THEN SLOWLY MIGRATE
EAST...BECOMING OVERHEAD THE CAROLINAS SATURDAY.

WHILE TUESDAY WILL BE UNSETTLED WITH TEMPS AROUND CLIMO...AND
WEDNESDAY WILL BE SIMILAR BUT DRY...MUCH COOLER AIR EXPECTED
THU-SAT. GUIDANCE DISAGREES ON JUST HOW COLD IT WILL GET HERE...BUT
ATTM SUPPORT THE COOLER GFS DUE TO STRONG CAA BEHIND THE LOW
PRESSURE OFF THE NE COAST. THIS DRAGS 850MB TEMPS BELOW
0C...SUPPORTING HIGHS IN THE MID 60S AND LOWS IN THE 40S. AS THE
HIGH MOVES OVERHEAD FRI INTO SAT...GRADIENT WILL RELAX...AND
SATURDAY MAY END UP BEING THE COLDEST OF THE PERIOD...WITH SATURDAY
MORNING LOWS IN SOME PLACES DROPPING INTO THE 30S.

&&

.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
AS OF 18Z...PRECIPITATION WILL COME TO AN END ALONG THE COAST
SHORTLY AFTER TAF ISSUANCE AS A SHORT WAVE MOVES FAIRLY RAPIDLY TO
THE NORTHEAST. SOME DRYING THIS AFTERNOON IS EXPECTED IN THE MID
LEVELS...BUT RETURNING SOMEWHAT TONIGHT AS A COLD FRONT APPROACHES.
LOOK FOR FROPA AROUND 06-08Z WITH A WIND SHIFT TO THE NORTH
NORTHWEST AND A MID CLOUD CEILING...POST FRONTAL. SUNDAY...SKIES
WILL BECOME SCATTERED BY MID TO LATE MORNING AND WINDS WILL BECOME
GUSTY WITH MODERATE COLD AIR ADVECTION.

EXTENDED OUTLOOK...VFR THROUGH THE EXTENDED. LIGHT RAIN DEVELOPING
TUESDAY MORNING INTO WEDNESDAY IN ASSOCIATION WITH AN APPROACHING
FRONTAL SYSTEM.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 6 PM SATURDAY...HIGH PRESSURE APPROACHING FROM THE WEST WILL
BRING A WIND-SHIFT TO NORTH TO THE COASTAL WATERS AROUND 2AM OVER
THE NC WATERS AND BY 5AM SOUTH CAROLINA WATERS. THIS SURGE OF
NORTH WIND WILL BRING INCREASING WIND SPEEDS OF 15 KT AND GUSTY
INTO EARLY SUNDAY...ALTHOUGH THE MAINLY NORTH TRAJECTORY/OFFSHORE
WILL KEEP SEAS RELATIVELY SMALL INSHORE...WITH LARGEST SEAS OUTER
PORTION. THE MODERATE NORTH CHOP WILL INTERACT WITH  2 FT OF ESE
WAVES IN 8-9 SECOND INTERVALS. SHOWERS AND ISOLATED TSTMS WILL BE
POSSIBLE OVERNIGHT.

SHORT TERM /SUNDAY THROUGH MONDAY
NIGHT/... AS OF 3 PM SATURDAY...FRONT WILL BE SHIFTING SOUTH AND
EAST AND SHOULD CLEAR LOCAL WATERS BY SUNDAY MORNING. HIGH
PRESSURE WILL BUILD IN BEHIND IT WITH NORTHERLY WINDS AROUND 10 TO
15 KTS. WINDS WILL VEER AROUND TO THE NORTHEAST SUNDAY NIGHT INTO
MONDAY AS HIGH PRESSURE MOVES OFF THE DELMARVA COAST. MAY SEE
SLIGHT SPIKE IN WINDS AND SEAS SUNDAY NIGHT IN COOL AND DRY
ADVECTION. WINDS WILL WEAKEN THROUGH MONDAY INTO MONDAY NIGHT AS
FRONT SHIFTS BACK NORTHWEST TOWARD THE CAPE FEAR COAST. OVERALL
LIGHT WIND FLOW WILL MAINTAIN SEAS 2 TO 3 FT BUT MAY SEE A FEW 4
FTERS IN OUTER WATERS SUNDAY NIGHT.

LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 3 PM SATURDAY...STALLED BOUNDARY ACROSS THE WATERS WILL KEEP
WINDS LIGHT AND GENERALLY OUT OF THE NORTH TUE. PASSAGE OF WEAK
SURFACE WAVE DURING THE DAY TUE MAY RESULT IN WINDS BECOMING MORE
VARIABLE BUT LITTLE CHANGE TO GRADIENT...AND THUS WIND SPEED...IS
EXPECTED. NORTHWEST FLOW DEVELOPS IN ERNEST WED WITH WINDS
BECOMING 10 TO 15 KT. WINDS COULD BECOME GUSTY WED NIGHT AS FIRST
ROUND OF COLD ADVECTION BEGINS.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...MJC
SHORT TERM...RGZ
LONG TERM...JDW
AVIATION...SGL










AREA FORECAST DISCUSSION

NWS RALEIGH NC

 145 PM EDT SAT OCT 19 2013

.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION LATE THIS EVENING. WEAK HIGH
PRESSURE WILL BUILD OVER THE AREA THROUGH EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 AM SATURDAY...

THROUGH THIS EVENING...
20-30KT OF 925/850MB FLOW AND WEAK ISENTROPIC LIFT BETWEEN A COASTAL
FRONT AND AN 850MB FRONT OVER THE WESTERN PIEDMONT CONTINUES TO
SUPPORT AREAS OF LIGHT RAIN THIS MORNING...MAINLY OVER THE FOOTHILLS
AND WESTERN PIEDMONT.  UPPER DIVERGENCE ASSOCIATED WITH THE RIGHT
ENTRANCE REGION OF A 150KT 300MB JET WEST OF THE MOUNTAINS SHOULD
OFFER ADDITIONAL LIFT THROUGH THIS AFTERNOON...WHILE THE MAIN AXIS
OF DEEP MOISTURE SHIFTS EASTWARD ACROSS THE CWA AHEAD OF AN UPPER
TROUGH THAT WILL BEGIN TO LIFT OUT OF THE MID MISSISSIPPI VALLEY
REGION.  MODELS STILL SHOW QUITE A BIT OF DRYING CENTERED AROUND
850MB AFTER 18Z AS THE FLOW VEERS TO A BIT MORE
WEST-SOUTHWESTERLY...WHICH SHOULD EFFECTIVELY SHUT OFF THE LIGHT
PRECIP...EVEN AS THE NORTHWESTERN PORTION OF THE CWA GETS A GLANCING
BLOW OF 60M HEIGHT FALLS AND THE COLD FRONT ENTERS THE AREA FROM THE
WEST.  WILL EXTEND A CHANCE POP INTO THE AFTERNOON BEFORE BRINGING
POPS TO AN END FROM WEST TO EAST THIS EVENING WITH THE IMPENDING
FRONTAL PASSAGE.

THE LIGHT RAIN OVERNIGHT HAS LEFT A WEAK STABLE LAYER NEAR THE
SURFACE AND WIDESPREAD LOW STRATUS.  DRY AIR ADVECTING IN FROM THE
SOUTHWEST WILL SLOWLY ERODE THE LOW CLOUDS TODAY...BUT EXPECT THE
LOW CLOUDS WILL LINGER INTO THE AFTERNOON WITHOUT A SIGNIFICANT
EROSION MECHANISM PRIOR TO THE COLD FRONT THIS EVENING. EVEN AS THE
LOW CLOUDS BREAK...THERE WILL ABUNDANT MID AND HIGH CLOUDS TO TEMPER
HIGHS.  THE LATEST RAP RUNS APPEAR TO HAVE A BETTER HANDLE OF
THIS...SO HAVE ADJUSTED TEMPS TOWARD THE RAP AND LOCAL WRF
ARW...WHICH SHOW A SLOW WARMING TREND THROUGH EARLY AFTERNOON.
HIGHS SHOULD END UP IN THE MID 60S ACROSS THE NORTHERN AREAS AND
POSSIBLE THE LOWER 70S ACROSS THE SOUTH. -SMITH

TONIGHT...
SHEARED SHORTWAVE TROUGH LIFTING NEWD INTO THE GREAT LAKES
AND NORTHEAST WILL DRAG THE TRAILING SFC COLD FRONT ACROSS THE THE
MOUNTAINS LATE THIS AFTERNOON AND ACROSS CENTRAL NC THIS EVENING
BETWEEN 00 TO 06Z. LIMITED MOISTURE...WEAK FORCING AND THE LACK OF
INSTABILITY WILL PREEMPT ANY PRECIP WITH DRY COLD AIR ADVECTION FOR
THE SECOND HALF OF THE NIGHT SPREADING WEST TO EAST. MUCH COOLER
WITH LOWS RANGING FROM MID 40S NW TO LOWER 50S SE. -CBL

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 240 AM SATURDAY...

POST-FRONTAL CAA REGIME SUNDAY MORNING WILL RESULT IN
LOW-LEVEL THICKNESSES STARTING OUT A GOOD 30 METERS BELOW
NORMAL...MORE REPRESENTATIVE OF LATE NOVEMBER THAN LATE OCTOBER.
IN-HOUSE TEMPERATURE FORECASTING TECHNIQUES ARE A GOOD 4 TO 6
DEGREES COOLER THAN MOS STATISTICAL GUIDANCE WITH FORECAST HIGHS ON
SUNDAY. UNDER COMPLIMENTS OF FULL SUNSHINE...EXPECT AFTERNOON HIGHS
IN THE LOWER TO MID 60S ACROSS THE PIEDMONT/NORTHERN COASTAL
PLAIN...TO MID/UPPER 60S SOUTH.

UPPER HEIGHTS LEVEL OUT A BIT OVER THE REGION AS LONG WAVE TROUGH
CENTERED BACK OVER THE CENTRAL US AWAITS RE-LOADING FROM A
SUCCESSION OF BOTH PACIFIC NW AND CANADIAN S/W ENERGY DIVING SEWD
THROUGH THE NATIONS MID-SECTION. THUS...SWLY FLOW ALOFT WILL
CONTINUE WITH LATEST GFS SHOWING A RESURGENCE OF HIGH-LEVEL MOISTURE
BACK ACROSS THE AREA LATE SUNDAY NIGHT...ESPECIALLY ACROSS THE
SOUTHERN HALF. WILL HAVE TO MONITOR CLOUD TRENDS AS THESE HIGHS
CLOUDS COULD MODULATE WHAT OTHERWISE WOULD BE GOOD RADIATIONAL
CONDITIONS WITH SFC HIGH PRESSURE CENTERED OVER THE AREA. LOWS IN
THE LOWER TO MID 40S.

 &&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 240 AM SATURDAY...

THE UPPER LEVEL LOW OVER SOUTH CENTRAL CANADA MONDAY WILL SWING
THROUGH THE GREAT LAKES REGION AND INTO NORTHEAST CANADA THROUGH
FRIDAY...WITH THE TROUGH SLOWLY PROGRESSING EAST FROM THE MIDWEST TO
THE ATLANTIC COAST. AT THE SURFACE...HIGH PRESSURE TO START THE
PERIOD WILL BE PUSHED NORTH AND EAST OFFSHORE BY A COLD FRONT MOVING
THROUGH THE CAROLINAS BY MID-WEEK. BEHIND THE FRONT...HIGH PRESSURE
WILL BUILD IN...BRINGING WITH IT A COOLER DRIER POLAR AIRMASS...
WHICH SHOULD LINGER THROUGH THE REMAINDER OF THE PERIOD. MODELS
INDICATE A SURGE OF MOISTURE FROM THE GULF MOVING INTO CENTRAL AND
EASTERN NC TUESDAY...AHEAD OF THE COLD FRONTAL PASSAGE...WHICH COULD
BRING AN INCREASE IN UPPER AND MID LEVEL CLOUD COVER MONDAY EVENING
AND INTO THE OVERNIGHT. WITH THE LATEST MODEL SOLUTIONS...EXPECT
BEST CHANCES FOR RAIN TO BE ACROSS THE EAST TUESDAY. ALTHOUGH THERE
MAY BE SOME LINGERING LOW LEVEL MOISTURE ACROSS THE AREA WEDNESDAY
AND WEDNESDAY NIGHT AND LIGHT RAIN CANNOT BE RULED OUT COMPLETELY...
DRY AIR IS EXPECTED TO BE IN PLACE AT THE MID AND UPPER LEVELS...
WITH NORTH TO NORTHWEST FLOW IN THE LOW LEVELS...WHICH SHOULD HELP
TO INHIBIT ADDITIONAL RAINFALL. AS FOR TEMPERATURES...WILL SEE A
STEADY DECREASE IN HIGHS THROUGH THE PERIOD...BEGINNING IN THE UPPER
60S TO LOW 70S ON MONDAY AND UPPER 50S TO MID 60S BY FRIDAY. EXPECT
OVERNIGHT LOWS TO BE THE COOLEST OF THE SEASON BY MID TO LATE IN THE
PERIOD...STARTING IN THE UPPER 40S TO LOW 50S MONDAY NIGHT...
DECREASING INTO THE MID 30S TO LOW 40S BY WEDNESDAY NIGHT...HOLDING
THROUGH THE END OF THE PERIOD.



&&

.AVIATION /18Z SATURDAY THROUGH WEDNESDAY/...
AS OF 145 PM SATURDAY...

24-HOUR TAF PERIOD...

LIGHT RAIN CONTINUES TO STREAM ACROSS THE WESTERN PIEDMONT THIS
AFTERNOON...AND LOW CEILINGS HAVE HELD ACROSS NEARLY ALL OF CENTRAL
NC. HOWEVER... THESE IFR CEILINGS ARE BEGINNING TO ERODE FROM THE
SOUTHWEST AND MVFR OR VFR CONDITIONS SHOULD DEVELOP AT ALL SITES BY
20-21Z. AS THIS DRIER AIR MOVES IN FROM THE WEST AND
SOUTHWEST...PRECIP IS BEGINNING TO DIMINISH...AND THE COLD FRONT
FORECAST TO CROSS THE AREA LATE THIS EVENING SHOULD BE MOSTLY DRY.
WINDS WILL SHIFT TO NORTHWESTERLY BEHIND THE FRONT BUT WILL REMAIN
BELOW 12KT.  VFR CONDITIONS AND LIGHT NORTH-NORTHWESTERLY WINDS WILL
CONTINUE THROUGH THE TAF PERIOD.

LOOKING AHEAD:
HIGH PRESSURE WILL DOMINATE THE WEATHER ACROSS NC EARLY NEXT WEEK.
THERE IS A SMALL CHANCE OF SUB-VFR CONDITIONS RETURNING BY THE
MIDDLE OF NEXT WEEK...MAINLY AT EASTERN SITES...AS A FRONTAL ZONE
LINGERS NEAT THE COAST.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...CBL
NEAR TERM...CBL/SMITH
SHORT TERM...CBL
LONG TERM...KMC
AVIATION...CBL













AREA FORECAST DISCUSSION

NWS RALEIGH NC

 1015 AM EDT SAT OCT 19 2013

.SYNOPSIS...
A WEAK SURFACE WAVE OF LOW PRESSURE WILL TRACK NORTH ALONG A STALLED
FRONTAL ZONE DRAPED ACROSS THE SOUTHEAST/NC COAST THIS MORNING. A
STRONGER SECONDARY COLD FRONT WILL CROSS THE REGION LATE THIS
EVENING. WEAK HIGH PRESSURE WILL BUILD OVER THE AREA THROUGH EARLY
NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 AM SATURDAY...

THROUGH THIS EVENING...
20-30KT OF 925/850MB FLOW AND WEAK ISENTROPIC LIFT BETWEEN A COASTAL
FRONT AND AN 850MB FRONT OVER THE WESTERN PIEDMONT CONTINUES TO
SUPPORT AREAS OF LIGHT RAIN THIS MORNING...MAINLY OVER THE FOOTHILLS
AND WESTERN PIEDMONT.  UPPER DIVERGENCE ASSOCIATED WITH THE RIGHT
ENTRANCE REGION OF A 150KT 300MB JET WEST OF THE MOUNTAINS SHOULD
OFFER ADDITIONAL LIFT THROUGH THIS AFTERNOON...WHILE THE MAIN AXIS
OF DEEP MOISTURE SHIFTS EASTWARD ACROSS THE CWA AHEAD OF AN UPPER
TROUGH THAT WILL BEGIN TO LIFT OUT OF THE MID MISSISSIPPI VALLEY
REGION.  MODELS STILL SHOW QUITE A BIT OF DRYING CENTERED AROUND
850MB AFTER 18Z AS THE FLOW VEERS TO A BIT MORE
WEST-SOUTHWESTERLY...WHICH SHOULD EFFECTIVELY SHUT OFF THE LIGHT
PRECIP...EVEN AS THE NORTHWESTERN PORTION OF THE CWA GETS A GLANCING
BLOW OF 60M HEIGHT FALLS AND THE COLD FRONT ENTERS THE AREA FROM THE
WEST.  WILL EXTEND A CHANCE POP INTO THE AFTERNOON BEFORE BRINGING
POPS TO AN END FROM WEST TO EAST THIS EVENING WITH THE IMPENDING
FRONTAL PASSAGE.

THE LIGHT RAIN OVERNIGHT HAS LEFT A WEAK STABLE LAYER NEAR THE
SURFACE AND WIDESPREAD LOW STRATUS.  DRY AIR ADVECTING IN FROM THE
SOUTHWEST WILL SLOWLY ERODE THE LOW CLOUDS TODAY...BUT EXPECT THE
LOW CLOUDS WILL LINGER INTO THE AFTERNOON WITHOUT A SIGNIFICANT
EROSION MECHANISM PRIOR TO THE COLD FRONT THIS EVENING. EVEN AS THE
LOW CLOUDS BREAK...THERE WILL ABUNDANT MID AND HIGH CLOUDS TO TEMPER
HIGHS.  THE LATEST RAP RUNS APPEAR TO HAVE A BETTER HANDLE OF
THIS...SO HAVE ADJUSTED TEMPS TOWARD THE RAP AND LOCAL WRF
ARW...WHICH SHOW A SLOW WARMING TREND THROUGH EARLY AFTERNOON.
HIGHS SHOULD END UP IN THE MID 60S ACROSS THE NORTHERN AREAS AND
POSSIBLE THE LOWER 70S ACROSS THE SOUTH. -SMITH

TONIGHT...
SHEARED SHORTWAVE TROUGH LIFTING NEWD INTO THE GREAT LAKES
AND NORTHEAST WILL DRAG THE TRAILING SFC COLD FRONT ACROSS THE THE
MOUNTAINS LATE THIS AFTERNOON AND ACROSS CENTRAL NC THIS EVENING
BETWEEN 00 TO 06Z. LIMITED MOISTURE...WEAK FORCING AND THE LACK OF
INSTABILITY WILL PREEMPT ANY PRECIP WITH DRY COLD AIR ADVECTION FOR
THE SECOND HALF OF THE NIGHT SPREADING WEST TO EAST. MUCH COOLER
WITH LOWS RANGING FROM MID 40S NW TO LOWER 50S SE. -CBL

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 240 AM SATURDAY...

POST-FRONTAL CAA REGIME SUNDAY MORNING WILL RESULT IN
LOW-LEVEL THICKNESSES STARTING OUT A GOOD 30 METERS BELOW
NORMAL...MORE REPRESENTATIVE OF LATE NOVEMBER THAN LATE OCTOBER.
IN-HOUSE TEMPERATURE FORECASTING TECHNIQUES ARE A GOOD 4 TO 6
DEGREES COOLER THAN MOS STATISTICAL GUIDANCE WITH FORECAST HIGHS ON
SUNDAY. UNDER COMPLIMENTS OF FULL SUNSHINE...EXPECT AFTERNOON HIGHS
IN THE LOWER TO MID 60S ACROSS THE PIEDMONT/NORTHERN COASTAL
PLAIN...TO MID/UPPER 60S SOUTH.

UPPER HEIGHTS LEVEL OUT A BIT OVER THE REGION AS LONG WAVE TROUGH
CENTERED BACK OVER THE CENTRAL US AWAITS RE-LOADING FROM A
SUCCESSION OF BOTH PACIFIC NW AND CANADIAN S/W ENERGY DIVING SEWD
THROUGH THE NATIONS MID-SECTION. THUS...SWLY FLOW ALOFT WILL
CONTINUE WITH LATEST GFS SHOWING A RESURGENCE OF HIGH-LEVEL MOISTURE
BACK ACROSS THE AREA LATE SUNDAY NIGHT...ESPECIALLY ACROSS THE
SOUTHERN HALF. WILL HAVE TO MONITOR CLOUD TRENDS AS THESE HIGHS
CLOUDS COULD MODULATE WHAT OTHERWISE WOULD BE GOOD RADIATIONAL
CONDITIONS WITH SFC HIGH PRESSURE CENTERED OVER THE AREA. LOWS IN
THE LOWER TO MID 40S.

 &&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 240 AM SATURDAY...

THE UPPER LEVEL LOW OVER SOUTH CENTRAL CANADA MONDAY WILL SWING
THROUGH THE GREAT LAKES REGION AND INTO NORTHEAST CANADA THROUGH
FRIDAY...WITH THE TROUGH SLOWLY PROGRESSING EAST FROM THE MIDWEST TO
THE ATLANTIC COAST. AT THE SURFACE...HIGH PRESSURE TO START THE
PERIOD WILL BE PUSHED NORTH AND EAST OFFSHORE BY A COLD FRONT MOVING
THROUGH THE CAROLINAS BY MID-WEEK. BEHIND THE FRONT...HIGH PRESSURE
WILL BUILD IN...BRINGING WITH IT A COOLER DRIER POLAR AIRMASS...
WHICH SHOULD LINGER THROUGH THE REMAINDER OF THE PERIOD. MODELS
INDICATE A SURGE OF MOISTURE FROM THE GULF MOVING INTO CENTRAL AND
EASTERN NC TUESDAY...AHEAD OF THE COLD FRONTAL PASSAGE...WHICH COULD
BRING AN INCREASE IN UPPER AND MID LEVEL CLOUD COVER MONDAY EVENING
AND INTO THE OVERNIGHT. WITH THE LATEST MODEL SOLUTIONS...EXPECT
BEST CHANCES FOR RAIN TO BE ACROSS THE EAST TUESDAY. ALTHOUGH THERE
MAY BE SOME LINGERING LOW LEVEL MOISTURE ACROSS THE AREA WEDNESDAY
AND WEDNESDAY NIGHT AND LIGHT RAIN CANNOT BE RULED OUT COMPLETELY...
DRY AIR IS EXPECTED TO BE IN PLACE AT THE MID AND UPPER LEVELS...
WITH NORTH TO NORTHWEST FLOW IN THE LOW LEVELS...WHICH SHOULD HELP
TO INHIBIT ADDITIONAL RAINFALL. AS FOR TEMPERATURES...WILL SEE A
STEADY DECREASE IN HIGHS THROUGH THE PERIOD...BEGINNING IN THE UPPER
60S TO LOW 70S ON MONDAY AND UPPER 50S TO MID 60S BY FRIDAY. EXPECT
OVERNIGHT LOWS TO BE THE COOLEST OF THE SEASON BY MID TO LATE IN THE
PERIOD...STARTING IN THE UPPER 40S TO LOW 50S MONDAY NIGHT...
DECREASING INTO THE MID 30S TO LOW 40S BY WEDNESDAY NIGHT...HOLDING
THROUGH THE END OF THE PERIOD.



&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
AS OF 623 AM SATURDAY...

24-HR TAF PERIOD:
A WEAK AREA OF LOW PRESSURE WILL MOVE NORTH-NORTHEASTWARD ALONG A
STALLED FRONT ACROSS COASTAL PORTIONS OF THE CAROLINAS THIS MORNING.
LOW-LEVEL MOISTURE CONVERGENCE ALONG THE LOW PRESSURE WILL RESULT IN
SOME RAIN AND WIDESPREAD SUB-VFR CONDITIONS ACROSS THE AREA THROUGH
LATE MORNING/MIDDAY(15-17Z)....WITH THE HEAVIEST RAINFALL AND MOST
ADVERSE AVIATION IMPACTS OCCURRING IN THE EAST. CIGS WILL RANGE FROM
LIFR AT KFAY/KRWI TO GENERALLY MVFR FOR KGSO/KINT.

AS THE AFOREMENTIONED SURFACE LOW LIFTS OFF TO THE NORTHEAST...
LOW-LEVEL FLOW WILL VEER TO WEST-SOUTHWESTERLY ADVECTING DRIER AIR
INTO THE AREA...WHICH SHOULD ALLOW CEILINGS TO LIFT AND IMPROVE TO
VFR FROM SW TO NE BETWEEN 15-18Z. A DRY COLD FRONT WILL MOVE THROUGH
THE AREA FROM WEST TO EAST BETWEEN 00Z TO 06. SFC WINDS WILL SWING
AROUND TO NWLY BEHIND THE FRONT.


LOOKING AHEAD:
VFR CONDITIONS CONDITIONS SHOULD RETURN SATURDAY EVENING/NIGHT/ WITH
THE PASSAGE OF A DRY COLD FRONT. DRY HIGH PRESSURE WILL RULE SUNDAY
AND INTO EARLY NEXT WEEK...WITH THE NEXT CHANCE FOR PRECIP AND
POSSIBLY SUB-VFR CONDITIONS ON TUESDAY AS A WAVY FRONTAL ZONE
DEVELOPS NEAR THE SE/NC COAST.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...CBL
NEAR TERM...CBL/SMITH
SHORT TERM...CBL
LONG TERM...KMC
AVIATION...CBL










AREA FORECAST DISCUSSION

NWS NEWPORT/MOREHEAD CITY NC

 252 AM EDT SAT OCT 19 2013

.SYNOPSIS...
A WAVE OF LOW PRESSURE WILL FORM ALONG A STATIONARY FRONT OFFSHORE
AND MOVE ALONG THE COAST TONIGHT AND OFF TO THE NORTHEAST
SATURDAY. A SECONDARY COLD FRONT WILL PUSH THROUGH THE AREA
SATURDAY NIGHT. HIGH PRESSURE WILL PASS THROUGH SUNDAY AND MONDAY.
ANOTHER COLD FRONT WILL PUSH THROUGH TUESDAY NIGHT. HIGH PRESSURE
WILL BUILD IN FROM THE NORTHWEST LATE IN THE WEEK.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF MIDNIGHT...LATEST RADAR IMAGERY SHOWING CONVECTIVE SHOWERS
INC IN COVERAGE...AND BANDED STRUCTURE OF THE PRECIP INDICATE
FGEN/OMEGA INC IN THE LOW/MID LEVELS PER LATEST RUC ANALYSIS. HAVE
CATEGORICAL POPS ACROSS COASTAL AREAS...WITH LIKELY POPS FOR THE
COASTAL PLAIN. HAVE CONTINUED MENTION OF SCT THUNDER WITH DECENT
INSTABILITY DEVELOPING OVERNIGHT EAST OF LOW TRACK ALONG THE HWY
17 CORRIDOR. QPF WILL RANGE A QUARTER TO HALF AN INCH OVERNIGHT
THOUGH LOCALLY HIGHER AMOUNTS WILL FALL WITH EMBEDDED
THUNDERSTORMS.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TODAY/...
AS OF 3 PM FRI...AREA OF LOW PRESSURE WILL MOVE OFF TO THE
NORTHEAST DURING MIDDAY. CONTINUED LIKELY POPS THROUGH THE FIRST
HALF OF THE DAY...THEN TAPERED OFF TO CHANCE MAINLY WEST OF
HIGHWAY 17 IN THE AFTERNOON. THICKNESSES AT 18Z SHOW LITTLE CHANGE
FROM THIS AFTERNOON SO NOT MUCH CHANGE IN FORECAST HIGH TEMPS.
EXPECTING LOWER 70S NORTHWEST TO MID 70S SOUTHEAST.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
UPPER TROUGH WILL SHIFT EAST OVER EASTERN CANADA AND NEW ENGLAND
WHILE THE COLD FRONT AND ASSOCIATED PRECIP PUSH OFF THE EASTERN
NC COAST EARLY SUNDAY MORNING. MODEST CAA BEHIND THE FRONT WILL
KEEP HIGH TEMPS AROUND 70F SUNDAY AS A SURFACE RIDGE SHIFTS EAST
OFF THE MID-ATLANTIC COAST LATE IN THE DAY. STRONG SW GRADIENT
ALOFT WILL PERSIST THROUGH TUES DUE TO BROAD HIGH HOLDING STRONG
OVER THE WESTERN ATLANTIC OCEAN AND LOW PRESSURE DIGGING SOUTH
THROUGH THE WESTERN GREAT LAKES. THE REGION SHOULD REMAIN DRY
THROUGH MONDAY WITH FRONT STALLING OFFSHORE. AN AREA OF LOW
PRESSURE WILL FORM ALONG THE STALLED BOUNDARY MON NIGHT INTO TUES
AND PUSH NE NEAR THE EASTERN NC COAST...AND THUS HAVE CONTINUED
PREVIOUS TREND OF HIGH CHANCE POPS EAST TAPERING BACK TO LOW CHANCE
DEEP INLAND. A SHORTWAVE IN MEAN SE FLOW ALOFT OVER THE CENTRAL
CONUS WILL ROTATE AROUND THE BASE OF THE POSITIVELY-TITLED UPPER
TROUGH TOWARDS EASTERN NC TUES NIGHT INTO WED...PUSHING A SURFACE
FRONT THROUGH EASTERN NC WED NIGHT WITH MUCH COOLER THAN NORMAL
TEMPS EXPECTED FOR LATE WEEK. WITH THE CONTINUING COLD AIR
INFILTRATING THE AREA, TEMPERATURES WILL SHOW A STEADY DECLINE
LATE IN THE WEEK WITH HIGHS WED UPPER 60S TRENDING COOLER TOWARD
THE LOWER 60S BY FRIDAY. LOWS AT NIGHT FOR INLAND AREAS WILL BE
QUITE COOL WITH LOW 40S WED NIGHT TRENDING TOWARD THE UPPER OR
POSSIBLY EVEN MID 30S LATE IN THE WEEK DUE TO HIGH PRESSURE AT
THE SURFACE WITH AN OVERALL DRY COLUMN SHOULD ALLOWING FOR
EXCELLENT RADIATIONAL COOLING.

&&

.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH SATURDAY/...
AS OF 650 PM FRI...WEAK LOW PRESSURE WILL MOVE NORTHEAST ALONG A
FRONT STALLED JUT OFF OF THE NC COAST TONIGHT AND SATURDAY. AS THE
LOW APPROACHES LATE THIS EVENING WIDESPREAD RAIN IS EXPECTED TO
DEVELOP OVER EASTERN NC TAPERING OFF SATURDAY. WIDESPREAD PRED
MVFR CEILINGS CONTINUE EARLY THIS EVENING...THEN A PERIOD OF IFR
CONDITIONS LIKELY TO DEVELOP OVERNIGHT AS WIDESPREAD RAIN DEVELOPS.
IFR CONDITIONS ARE EXPECTED TO LINGER INTO SATURDAY MORNING IN FOG
AND STRATUS. THE LOW CLOUDS AND FOG WILL DIMINISH BY SATURDAY
AFTERNOON WITH CEILINGS LIFTING THROUGH MVFR WITH SOME BRIEF VFR
CONDITIONS POSSIBLY DEVELOPING BY MID AFTERNOON.

LONG TERM /SUNDAY THROUGH WEDNESDAY/...
MAINLY VFR SUN AND MON AS HIGH PRESSURE CROSSES THE REGION. SOME
SCATTERED SHOWERS POSSIBLE TUES INTO TUES NIGHT AS AN AREA OF LOW
PRESSURE FORMS ALONG THE STALLED BOUNDARY OFF THE COAST AND PUSHES
NE OFF THE COAST THROUGH TUES NIGHT. SOME REDUCED CEILINGS AND
VSBYS ARE POSSIBLE...ESPECIALLY FOR EWN/OAJ CLOSER THE COAST.
RETURN TO VFR EXPECTED WED.

&&

.MARINE...
SHORT TERM /THROUGH SATURDAY/...
AS OF 1015 PM FRI...MARINE FORECAST IN GREAT SHAPE...NO CHANGES
NEEDED AT THIS TIME. THE LATEST BUOY OBS CONTINUE TO SHOW NE/E
WINDS 5-15 KT AND SEAS 2-4 FT. THE AREA OF LOW PRESSURE CONTINUES
TO DEVELOP ALONG A STATIONARY BOUNDARY OVER COASTAL SC. THIS LOW
PRESSURE WILL MOVE ALONG THE COAST OVERNIGHT AND IS EXPECTED TO
LIFT TO THE NE BY TOMORROW AFTERNOON. WINDS WILL BE VARIABLE
OVERNIGHT...VEERING INTO SATURDAY MORNING...EVENTUALLY BECOMING
WEST SOUTHWEST THROUGHOUT SATURDAY AFTERNOON. WIND SPEEDS AND SEAS
WILL REMAIN BELOW SMALL CRAFT LEVELS. WIDESPREAD RAIN EXPECTED
FROM LATE TONIGHT INTO MOST OF SATURDAY. SCATTERED THUNDER
POSSIBLE TONIGHT AND ISOLATED THUNDER POSSIBLE SATURDAY.

LONG TERM /SUNDAY THROUGH WEDNESDAY/...
A COLD FRONT CROSSES THE WATERS EARLY SUN MORNING WITH A BRIEF
SURGE OF NW TO N WINDS OF 15 TO 20 KTS. WINDS WILL QUICKLY SUBSIDE
TO 10 TO 15 KTS LATER SUN AND BECOME MORE NE AS HIGH PRES BUILDS
TO THE N. MAINLY NE WINDS 5 TO 15 KTS SUN NIGHT AND MON AS HIGH
PRES SLIDES OFFSHORE TO THE N. COLD FRONT WILL APPROACH FROM THE W
TUES WITH A WEAK WAVE DEVELOPING NEAR THE COAST AHEAD OF FRONT.
UNCERTAINTY REMAINS FOR WINDS/SEAS TUES/WED BUT FOR NOW LOOKS LIKE
SPEEDS WILL REMAIN AT OR BELOW 15KTS.

SEAS WILL BUILD TO 3 TO 5 FT CENTRAL AND NORTHERN WATERS EARLY
SUN IN WAKE OF FRONT. SEAS WILL SUBSIDE TO 2 TO 3 FT SUN NIGHT AND
CONT IN THAT RANGE INTO TUES. SEAS BUILD 2-4 FT TUES NIGHT THEN
3-5 FT...MAINLY FOR THE CENTRAL AND NORTHERN WATERS DUE TO
MODERATE NORTHERLY SURGE WED.

&&

.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...HSA
NEAR TERM...HSA/TL/BM
SHORT TERM...HSA
LONG TERM...BTC/DAG
AVIATION...BTC/HSA/CQD/DAG
MARINE...BTC/HSA/CQD/DAG/BM







AREA FORECAST DISCUSSION

NWS RALEIGH NC

 140 AM EDT SAT OCT 19 2013

.SYNOPSIS...
A WEAK SURFACE WAVE OF LOW PRESSURE WILL TRACK NORTH ALONG A STALLED
FRONTAL ZONE DRAPED ACROSS THE SOUTHEAST...NC COAST THIS MORNING.
A STRONGER SECONDARY COLD FRONT WILL CROSS THE REGION LATE THIS
EVENING. WEAK HIGH PRESSURE WILL BUILD OVER THE AREA THROUGH EARLY
NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 915 PM FRIDAY...

MAIN FORECAST CHALLENGE TONIGHT INTO SATURDAY IS HOW FAR WEST-NW
WILL THE THREAT FOR PATCHY LIGHT RAIN EXPAND ACROSS CENTRAL NC.

A SURFACE BOUNDARY REMAINS STALLED ACROSS THE IMMEDIATE SC COAST AMD
JUST OFFSHORE OF SE NC. A WEAK SFC LOW WAS NOTED IN THE SFC WIND
FIELD IN VICINITY OF MYRTLE BEACH. A WEAK SFC RIDGE DID EXTEND SW-NE
ACROSS THE PIEDMONT OF CENTRAL NC. THIS RIDGE IS VERY SHALLOW AS
AREAS VAD WIND PROFILES DEPICT A LIGHT NE WIND CONFINED TO THE
LOWEST 1-2K FT WITH SLY FLOW ALOFT. SFC DEWPOINTS UNDERNEATH THIS
RIDGE WERE IN THE LOW-MID 50S. MEANWHILE DEWPOINTS CLOSER TO
BOUNDARY WERE IN THE 60S.

WATER VAPOR IMAGERY DEPICTS A JETLET LIFTING NE ACROSS THE LOWER MS
VALLEY THIS EVENING ALONG WITH A MINOR MID LEVEL DISTURBANCE LIFTING
NE ACROSS SE LA AND SOUTHERN MS.

THE APPROACH OF THE MID LEVEL DISTURBANCE WILL MAINTAIN AND POSSIBLY
BACK THE FLOW IN THE 925-850MB LAYER OVERNIGHT INTO EARLY SATURDAY.
WHILE THE SLY FLOW IS NOT OVERLY STRONG...THE NEAR TERM MODEL
GUIDANCE DOES SUGGEST ENOUGH UPGLIDE TO CAUSE PATCHY LIGHT RAIN OVER
SECTIONS OF THE SANDHILLS AND THE COASTAL PLAIN. MOST MODEL GUIDANCE
SUGGEST MEASURABLE RAIN A POSSIBILITY AS FAR WEST AS SILER CITY AND
BURLINGTON. THE GFS MODEL VERIFIED FAIRLY WELL AT 00Z IN ITS PRECIP
DEPICTION FIELD WHILE THE 12Z ECMWF ALONG WITH A BULK OF THE CAM
MODELS WERE TOO AGGRESSIVE. LATEST RAP MODEL (23Z) DELAYS EXPANSION
UNTIL 07Z (SEEMS REASONABLE CONSIDERING THE MID LEVEL PERTURBATION
IS WELL SW OF OUR REGION AT 00Z) WITH MEASURABLE RAINFALL AS FAR
WEST AS THE NORTHERN MOUNTAINS AND FOOTHILLS SHORTLY AFTER 12Z
SATURDAY. AT THIS TIME...THIS SEEMS TOO AGGRESSIVE CONSIDERING THE
AMOUNT OF DRY AIR NOW RESIDING OVER THE WESTERN PIEDMONT (PER 00Z
GSO SOUNDING) AND WEAK TO NON-EXISTENT 850MB MOISTURE TRANSPORT
INTO THE PIEDMONT. PLAN TO MAINTAIN HIGHEST THREAT FOR MEASURABLE
RAIN EAST OF HIGHWAY 1...AND MOSTLY OVER THE COASTAL PLAIN.

MIN TEMPS WILL DEPEND UPON THE AREAL EXTENT OF RAIN (SE HALF) AND
THICKNESS OF CLOUD COVER (NW HALF). OVER THE NW HALF...PARTLY
CLOUDY SKIES HAVE ALLOWED TEMPS TO COOL INTO THE MID-UPPER 50S AT
MID EVENING. AS CLOUDS INCREASE/THICKEN...SHOULD SEE TEMPS STABILIZE
AND MAY ACTUALLY RISE A DEGREE OR TWO AFTER MIDNIGHT. OVER THE
EAST-SE...TEMPS WILL HOLD STEADY OR SHOW A VERY SLOW DECLINE THROUGH
THE NIGHT.

&&

.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
AS OF 245 PM FRIDAY...

PRECIP SHOULD BE COMING TO AN END SATURDAY MORNING AS A WEAK WAVE OF
LOW PRESSURE MOVES ACROSS THE COASTAL PLAIN AND OFF TO THE
NORTHEAST.  FORECAST SOUNDINGS SHOW A DEEP SOUTHWESTERLY FLOW AND
RAPID DRYING IN THE MID LEVELS AHEAD OF THE SHORTWAVE SWINGING
THROUGH THE MIDWEST...BUT IF WE GET SUFFICIENT RAIN OVERNIGHT...LOW
CLOUDS MAY BE SLOWER TO SCOUR THAT MODELS PROJECT.  ONCE CLOUDS DO
BREAK...LOWER 70S SHOULD BE ATTAINABLE.

A COLD FRONT WILL MOVE INTO WESTERN NC SATURDAY AFTERNOON AND CROSS
CENTRAL NC SATURDAY EVENING.  THE MAIN HEIGHT FALLS AND DPVA
ASSOCIATED WITH THE SHORTWAVE WILL PASS TO OUR NORTH...AND WITH
MID-LEVEL DYING AHEAD OF THE FRONT...THERE WILL BE LIMITED
FORCING/MOISTURE TO PRODUCE ANY PRECIP ALONG THE FRONT. ONLY THE
ECMWF SHOWS MUCH QPF ALONG THE FRONT...AND THIS APPEARS OVERDONE.
WILL MAINTAIN JUST A SLIGHT CHANCE DURING THE AFTERNOON.    COLD
ADVECTION WILL KICK IN SATURDAY NIGHT AND LOWS SHOULD DROP INTO THE
MID TO UPPER 40S FOR MUCH OF THE AREA.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 230 PM FRIDAY...

THE UPPER TROF OVER THE CENTRAL CONUS WILL BE IN PERSISTENT RELOAD
MODE THROUGH THE EXTENDED PERIOD...RESULTING IN UNSEASONABLY COOL
AND DRY WEATHER SETTLING...THEN DEEPENING OVER AREA NEXT WEEK.

WE WILL BE LOOKING AT MOSTLY CLEAR SKIES SUNDAY AND MONDAY AS HIGH
PRESSURE OVER THE AREA IS GRADUALLY SQUEEZED OFF TO THE NORTHEAST.
HIGHS WILL BE IN THE MID 60S NORTHWEST TO LOWER 70S SOUTHEAST BOTH
DAYS. AS THE HIGH MOVES OFF TO THE NORTHEAST...A FRONT WHICH HAS
BEEN LOOMING OFFSHORE SOUTH AND EAST OF THE AREA WILL MAKE A BRIEF
NORTHERLY AND WESTERLY SURGE. THE BROAD MOISTURE PLUME OF SOUTHERN
STREAM MOISTURE ASSOCIATED WITH THIS FRONT WILL SETTLE OVER THE
COASTAL PLAIN...PRODUCING A CHANCE OF SHOWERS IN THE EASTERN CWFA
LATER MONDAY NIGHT AND TUESDAY. THIS MOISTURE WILL BE SHUNTED
OFFSHORE BY A COLD FRONT LATE TUESDAY...WHICH WILL THEN USHER IN A
DEEPENING POLAR AIRMASS THROUGH THE END OF THE WEEK. HIGHS WEDNESDAY
WILL BE MAINLY IN THE MID 60S...WITH HIGHS BOTH THURSDAY AND FRIDAY
MOSTLY IN THE 60 TO 65 RANGES...BUT STRUGGLING TO REACH 60 IN THE
NORTHWEST. WE WILL SEE THE COLDEST TEMPS OF THE SEASON TO DATE AS
THE POLAR AIRMASS RADIATIONALLY COOLS OVERNIGHT...WITH MINS IN THE
40S SUNDAY THROUGH TUESDAY IN THE 40S...FALLING TO THE MID AND UPPER
30S WEDNESDAY AND THURSDAY NIGHTS.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 140 AM SATURDAY...

24-HR TAF PERIOD:
A WEAK AREA OF LOW PRESSURE WILL LIFT NORTH-NORTHEASTWARD ALONG THE
STALLED FRONT ALONG COASTAL PORTIONS OF THE CAROLINAS TONIGHT.
LOW-LEVEL MOISTURE CONVERGENCE ALONG THE LOW PRESSURE WILL RESULT IN
SOME RAIN AND WIDESPREAD SUB-VFR CONDITIONS ACROSS THE AREA THROUGH
LATE MORNING/MIDDAY(15-17Z)....WITH THE HEAVIEST RAINFALL AND MOST
ADVERSE AVIATION IMPACTS OCCURRING IN THE EAST. THUS... EXPECT WE
WILL SEE CIGS RANGE FROM IFR/LIFR AT KFAY/KRWI TO GENERALLY MVFR FOR
KGSO/KINT.

AS THE AFOREMENTIONED SURFACE LOW LIFTS OFF TO THE NORTHEAST...
LOW-LEVEL FLOW WILL VEER TO WEST-SOUTHWESTERLY ADVECTING DRIER AIR
INTO THE AREA...WHICH SHOULD ALLOW CEILINGS TO IMPROVE TO VFR
BY 18Z OR SOON AFTER. THEN BETWEEN 00 TO 06Z SUNDAY...A DRY COLD
FRONT WILL MOVE THROUGH THE AREA. SFC WINDS WILL SWING AROUND TO
NWLY BEHIND THE FRONT.


LOOKING AHEAD:
VFR CONDITIONS CONDITIONS SHOULD RETURN SATURDAY EVENING/NIGHT/ WITH
THE PASSAGE OF A DRY COLD FRONT. DRY HIGH PRESSURE WILL RULE SUNDAY
AND INTO EARLY NEXT WEEK...WITH THE NEXT CHANCE FOR PRECIP AND
POSSIBLY SUB-VFR CONDITIONS ON TUESDAY AS A WAVY FRONTAL ZONE
DEVELOPS NEAR THE SE/NC COAST.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...CBL
NEAR TERM...WSS
SHORT TERM...SMITH
LONG TERM...MLM
AVIATION...CBL









AREA FORECAST DISCUSSION

NWS NEWPORT/MOREHEAD CITY NC

 1200 AM EDT SAT OCT 19 2013

.SYNOPSIS...
A WAVE OF LOW PRESSURE WILL FORM ALONG A STATIONARY FRONT OFFSHORE
AND MOVE ALONG THE COAST TONIGHT AND OFF TO THE NORTHEAST
SATURDAY. A SECONDARY COLD FRONT WILL PUSH THROUGH THE AREA
SATURDAY NIGHT. HIGH PRESSURE WILL PASS THROUGH SUNDAY AND MONDAY.
ANOTHER COLD FRONT WILL PUSH THROUGH TUESDAY NIGHT. HIGH PRESSURE
WILL BUILD IN FROM THE NORTHWEST LATE IN THE WEEK.

&&

.NEAR TERM /OVERNIGHT/...
AS OF MIDNIGHT...LATEST RADAR IMAGERY SHOWING CONVECTIVE SHOWERS
INC IN COVERAGE...AND BANDED STRUCTURE OF THE PRECIP INDICATE
FGEN/OMEGA INC IN THE LOW/MID LEVELS PER LATEST RUC ANALYSIS. HAVE
CATEGORICAL POPS ACROSS COASTAL AREAS...WITH LIKELY POPS FOR THE
COASTAL PLAIN. HAVE CONTINUED MENTION OF SCT THUNDER WITH DECENT
INSTABILITY DEVELOPING OVERNIGHT EAST OF LOW TRACK ALONG THE HWY
17 CORRIDOR. QPF WILL RANGE A QUARTER TO HALF AN INCH OVERNIGHT
THOUGH LOCALLY HIGHER AMOUNTS WILL FALL WITH EMBEDDED
THUNDERSTORMS.

&&

.SHORT TERM /SATURDAY/...
AS OF 3 PM FRI...AREA OF LOW PRESSURE WILL MOVE OFF TO THE
NORTHEAST DURING MIDDAY. CONTINUED LIKELY POPS THROUGH THE FIRST
HALF OF THE DAY...THEN TAPERED OFF TO CHANCE MAINLY WEST OF
HIGHWAY 17 IN THE AFTERNOON. THICKNESSES AT 18Z SHOW LITTLE CHANGE
FROM THIS AFTERNOON SO NOT MUCH CHANGE IN FORECAST HIGH TEMPS.
EXPECTING LOWER 70S NORTHWEST TO MID 70S SOUTHEAST.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
AS OF 315 PM FRI...UPPER TROUGH WILL SHIFT EAST OVER EASTERN
CANADA AND NEW ENGLAND SAT NIGHT WHILE THE COLD FRONT AND
ASSOCIATED PRECIP PUSH OFF THE EASTERN NC COAST. CONTINUED
PREVIOUS TREND OF POPS ENDING FROM WEST TO EAST SAT NIGHT AND
COMPLETELY OFF THE COAST AROUND SUNRISE SUN MORNING. MODEST CAA
BEHIND THE FRONT WILL KEEP TEMPS 69-71 F SUN AS A SURFACE RIDGE
SHIFTS EAST OFF THE MID-ATLANTIC COAST. STRONG SW GRADIENT ALOFT
WILL PERSIST THROUGH TUES DUE TO BROAD HIGH HOLDING STRONG OVER
THE WESTERN ATLANTIC OCEAN AND LOW PRESSURE DIGGING SOUTH THROUGH
THE WESTERN GREAT LAKES. THE REGION SHOULD REMAIN DRY SUN THROUGH
MON WITH SATURDAY NIGHTS FRONT STALLING OFFSHORE. AN AREA OF LOW
PRESSURE WILL FORM ALONG THE STALLED BOUNDARY MON NIGHT INTO TUES
AND PUSH NE NEAR THE EASTERN NC COAST...AND THUS HAVE CONTINUED
PREVIOUS TREND OF HIGHER POPS EAST OF HWY 17 AND SLIGHT CHANCE
POPS INLAND. A SHORTWAVE IN MEAN SE FLOW ALOFT OVER THE CENTRAL
CONUS WILL ROTATE AROUND THE BASE OF THE POSITIVELY-TITLED UPPER
TROUGH TOWARDS EASTERN NC TUES NIGHT INTO WED...PUSHING A
SURFACE FRONT THROUGH EASTERN NC WED NIGHT WITH MUCH COOLER THAN
NORMAL TEMPS EXPECTED FOR LATE WEEK. LOW LEVEL THICKNESSES DROP
TO 1330-1340 METERS THURS...1320-1330 METERS FRI...YIELDING MAX
TEMPS IN THE LOW 60S BOTH DAYS. MIN TEMPS WILL FALL INTO THE LOWER
40S WED NIGHT THROUGH FRI NIGHT DUE TO HIGH PRESSURE AT THE
SURFACE WITH AN OVERALL DRY COLUMN SHOULD ALLOW FOR EXCELLENT
RADIATIONAL COOLING.

&&

.AVIATION /04Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH SATURDAY/...
AS OF 650 PM FRI...WEAK LOW PRESSURE WILL MOVE NORTHEAST ALONG A
FRONT STALLED JUT OFF OF THE NC COAST TONIGHT AND SATURDAY. AS THE
LOW APPROACHES LATE THIS EVENING WIDESPREAD RAIN IS EXPECTED TO
DEVELOP OVER EASTERN NC TAPERING OFF SATURDAY. WIDESPREAD PRED
MVFR CEILINGS CONTINUE EARLY THIS EVENING...THEN A PERIOD OF IFR
CONDITIONS LIKELY TO DEVELOP OVERNIGHT AS WIDESPREAD RAIN DEVELOPS.
IFR CONDITIONS ARE EXPECTED TO LINGER INTO SATURDAY MORNING IN FOG
AND STRATUS. THE LOW CLOUDS AND FOG WILL DIMINISH BY SATURDAY
AFTERNOON WITH CEILINGS LIFTING THROUGH MVFR WITH SOME BRIEF VFR
CONDITIONS POSSIBLY DEVELOPING BY MID AFTERNOON.

LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 330 PM FRI...MOISTURE LINGERING BEHIND THE FRONT SAT NIGHT
MAY LEAD TO REDUCED VSBYS/CEILINGS PRIOR TO SUNRISE SUN MORNING. MAINLY
VFR SUN AND MON AS HIGH PRESSURE CROSSES THE REGION. SOME SCATTERED
SHOWERS POSSIBLE TUES INTO TUES NIGHT AS AN AREA OF LOW PRESSURE FORMS
ALONG THE STALLED BOUNDARY OFF THE COAST AND PUSHES NE OFF THE
COAST THROUGH TUES NIGHT. SOME REDUCED CEILINGS AND VSBYS ARE
POSSIBLE...ESPECIALLY FOR EWN/OAJ CLOSER THE COAST. RETURN TO VFR
EXPECTED WED.

&&

.MARINE...
SHORT TERM /THROUGH SATURDAY/...
AS OF 1015 PM FRI...MARINE FORECAST IN GREAT SHAPE...NO CHANGES
NEEDED AT THIS TIME. THE LATEST BUOY OBS CONTINUE TO SHOW NE/E
WINDS 5-15 KT AND SEAS 2-4 FT. THE AREA OF LOW PRESSURE CONTINUES
TO DEVELOP ALONG A STATIONARY BOUNDARY OVER COASTAL SC. THIS LOW
PRESSURE WILL MOVE ALONG THE COAST OVERNIGHT AND IS EXPECTED TO
LIFT TO THE NE BY TOMORROW AFTERNOON. WINDS WILL BE VARIABLE
OVERNIGHT...VEERING INTO SATURDAY MORNING...EVENTUALLY BECOMING
WEST SOUTHWEST THROUGHOUT SATURDAY AFTERNOON. WIND SPEEDS AND SEAS
WILL REMAIN BELOW SMALL CRAFT LEVELS. WIDESPREAD RAIN EXPECTED
FROM LATE TONIGHT INTO MOST OF SATURDAY. SCATTERED THUNDER
POSSIBLE TONIGHT AND ISOLATED THUNDER POSSIBLE SATURDAY.

LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 340 PM FRI...A COLD FRONT APPROACHES FROM THE NW SAT NIGHT
AND CROSSES THE WATERS BY SUN MORNING. EXPECT A BRIEF SURGE OF NW
TO N WINDS OF 15 TO 20 KTS EARLY SUNDAY. WINDS WILL QUICKLY
SUBSIDE TO 10 TO 15 KTS LATER SUN AND BECOME MORE NE AS HIGH PRES
BUILDS TO THE N. MAINLY NE WINDS 5 TO 15 KTS SUN NIGHT AND MON AS
HIGH PRES SLIDES OFFSHORE TO THE N. COLD FRONT WILL APPROACH FROM
THE W TUES WITH A WEAK WAVE DEVELOPING NEAR THE COAST AHEAD OF
FRONT. UNCERTAINTY REMAINS FOR WINDS/SEAS TUES/WED BUT FOR NOW
LOOKS LIKE SPEEDS WILL REMAIN BELOW 15KTS.

SEAS WILL CONTINUE AT 2 TO 4 FEET SAT EVENING THEN BUILD TO 3 TO
5 FT CENTRAL AND NORTHERN WATERS EARLY SUN IN WAKE OF FRONT. SEAS
WILL SUBSIDE TO 2 TO 3 FT SUN NIGHT AND CONT IN THAT RANGE INTO
TUES. SEAS BUILD 2-4 FT TUES NIGHT THEN 3-5 FT...MAINLY FOR THE
CENTRAL AND NORTHERN WATERS DUE TO MODERATE NORTHERLY SURGE WED.

&&

.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...HSA
NEAR TERM...TL
SHORT TERM...HSA
LONG TERM...DAG
AVIATION...HSA/CQD/DAG
MARINE...HSA/CQD/DAG/BM







AREA FORECAST DISCUSSION

NWS GRAND FORKS ND

 942 PM CDT SUN OCT 20 2013

.UPDATE...
ISSUED AT 936 PM CDT SUN OCT 20 2013

CLEARING CONTINUES TO EXPAND ACROSS SOUTHERN MB AND LOOKS TO BE
ENTERING FAR NORTHERN FA. WITH CURRENT TEMPERATURES AS THEY ARE EVEN
WITH MODEST MIXING ANY CLEARING SHOULD BE ABLE TO QUICKLY DROP
TEMPERATURES TO EXPECTED MINIMUMS SO FOR NOW WILL HOLD WITH
FORECAST MINS. UNTIL CLOUDS DECREASE ADDED FLURRIES WITH WEAK
RETURNS FROM KMVX-88D. MADE MORE ADJUSTMENTS TO CLOUD TRENDS WITH
REMAINDER OF FORECAST OK.

UPDATE ISSUED AT 641 PM CDT SUN OCT 20 2013

BIG CHALLENGE TONIGHT WILL BE MINIMUM TEMPERATURES WHICH WILL
HINGE ON CLOUD TRENDS. SOME BREAKS SHOWING UP IN SOUTHERN MB
HOWEVER STILL PRETTY SOLID CLOUD COVER ACROSS THE FA. WILL BE
MONITORING CLOUD TRENDS THROUGH THE EVENING. AT THIS POINT NOT
PLANNING ANY CHANGES OTHER THAN ADJUSTING CLOUD COVER A BIT.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 316 PM CDT SUN OCT 20 2013

CHALLENGES THROUGH THE PERIOD INCLUDE LOW END PRECIPITATION CHANCES
AND TEMPERATURES. GFS/NAM/ECMWF/GEM IN REASONABLE AGREEMENT AND
WILL FOLLOW AND BLENDED MODEL SOLUTION.

20 UTC SURFACE ANALYSIS SHOWS THE SURFACE LOW SOUTHWEST OF
MINNEAPOLIS AND MOST OF ITS ASSOCIATED PRECIPITATION ACROSS THE MN
ARROWHEAD INTO NORTHWEST WI. A COUPLE SURFACE OBS ACROSS WEST
CENTRAL MN STILL REPORTING LIGHT RAIN...BUT WITH VISIBILITY OF 10
SM...MOST LIKELY JUST SOME LINGERING SPRINKLES. WILL CONTINUE THIS
DRYING TREND INTO THE EARLY EVENING WITH ONLY SOME 20 POPS ACROSS
THE LAKE OF THE WOODS REGION OVERNIGHT AS THE SURFACE LOW PIVOTS
BACK TO THE NORTH AND ITS INVERTED TROUGH PINWHEELS ABOUT THE
INTERNATIONAL BORDER.

THERE IS ABUNDANT CLOUD COVER UPSTREAM...BUT IT IS MORE CELLULAR
IN NATURE...SO IT/S DIFFICULT TO SAY HOW MUCH CLEARING WILL OCCUR
OVERNIGHT...ESPECIALLY WHEN THE RAP 925 HPA RH SHOWS SATURATED
CONDITIONS THROUGH MONDAY MORNING. WILL SHOW SOME CLEARING WEST OF
THE VALLEY BY 12 UTC MONDAY...BUT THIS MAY BE OVERLY OPTIMISTIC.
EITHER WAY...WITH HIGHS THIS AFTERNOON IN THE 30S...NIGHTTIME
LOWS IN THE 20S SEEM REASONABLE.

BEST CHANCE FOR PRECIPITATION MONDAY WILL CONTINUE ACROSS THE LAKE
OF THE WOODS REGION WITH ALL OTHER AREAS DRY. SHOULD SEE A BIT
MORE SUN TO THE SOUTH AND WEST...BUT COLD AIR MASS WILL KEEP
HIGH TEMPERATURES IN THE 30S. NORTH-NORTHWEST WIND WILL PERSIST...
BUT WITH A WEAKENING PRESSURE GRADIENT...SHOULD BE A BIT LOWER
FROM 10 TO 15 MPH.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 316 PM CDT SUN OCT 20 2013

CANADIAN HIGH PRESSURE DIVES SOUTH ACROSS THE NORTHERN PLAINS
TUESDAY AND WEDNESDAY FOR MOSTLY DRY CONDITIONS. HOWEVER...
PERSISTENT CYCLONIC FLOW ALOFT COMBINED WITH HIGHER MID-LEVEL
MOISTURE WILL RESULT IN QUITE A BIT OF CLOUDS. MID-LEVEL THERMAL
RIDGE WILL NUDGE EASTWARD...ALLOWING FOR A LITTLE WARMING EACH
DAY...SO THAT HIGHS BY WEDNESDAY SHOULD APPROACH 40 DEGREES. THIS
IS STILL 10 TO 15 DEGREES BELOW MID-LATE OCTOBER NORMALS.

WED NIGHT-SUNDAY...NORTHWEST FLOW ALOFT THOUGH THE PERIOD. 12Z
MODELS ARE IN GOOD AGREEMENT INITIALLY...BUT QUICKLY DISAGREE WITH A
STRONGER WAVE FRIDAY INTO SUNDAY. THE GFS/GEM ARE MUCH QUICKER AND
FURTHER WEST WITH THIS WAVE THAN THE ECMWF. THE GFS/GEM BRING PRECIP
INTO NORTHWEST MINNESOTA WITH THIS FEATURE...WHILE THE ECMWF IS
BASICALLY DRY THROUGH THE PERIOD. TEMPERATURES WOULD ALSO BE
AFFECTED WITH EXACTLY WHERE THIS WAVE TRACKS. THE BLEND OF MODELS IS
LIKELY THE BEST COURSE OF ACTION.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 641 PM CDT SUN OCT 20 2013

ALL TAF SITES HAVE RISEN TO VFR CONDITIONS AND EXPECT CONDITIONS
TO CONTINUE THROUGH THE FORECAST PERIOD. WHETHER WE SCATTER OUT
WILL BE THE BIG QUESTION.


&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

UPDATE...VOELKER
SHORT TERM...ROGERS
LONG TERM...ROGERS/TG
AVIATION...VOELKER







AREA FORECAST DISCUSSION

NWS GRAND FORKS ND

 652 PM CDT SUN OCT 20 2013

.UPDATE...
ISSUED AT 641 PM CDT SUN OCT 20 2013

BIG CHALLENGE TONIGHT WILL BE MINIMUM TEMPERATURES WHICH WILL
HINGE ON CLOUD TRENDS. SOME BREAKS SHOWING UP IN SOUTHERN MB
HOWEVER STILL PRETTY SOLID CLOUD COVER ACROSS THE FA. WILL BE
MONITORING CLOUD TRENDS THROUGH THE EVENING. AT THIS POINT NOT
PLANNING ANY CHANGES OTHER THAN ADJUSTING CLOUD COVER A BIT.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 316 PM CDT SUN OCT 20 2013

CHALLENGES THROUGH THE PERIOD INCLUDE LOW END PRECIPITATION CHANCES
AND TEMPERATURES. GFS/NAM/ECMWF/GEM IN REASONABLE AGREEMENT AND
WILL FOLLOW AND BLENDED MODEL SOLUTION.

20 UTC SURFACE ANALYSIS SHOWS THE SURFACE LOW SOUTHWEST OF
MINNEAPOLIS AND MOST OF ITS ASSOCIATED PRECIPITATION ACROSS THE MN
ARROWHEAD INTO NORTHWEST WI. A COUPLE SURFACE OBS ACROSS WEST
CENTRAL MN STILL REPORTING LIGHT RAIN...BUT WITH VISIBILITY OF 10
SM...MOST LIKELY JUST SOME LINGERING SPRINKLES. WILL CONTINUE THIS
DRYING TREND INTO THE EARLY EVENING WITH ONLY SOME 20 POPS ACROSS
THE LAKE OF THE WOODS REGION OVERNIGHT AS THE SURFACE LOW PIVOTS
BACK TO THE NORTH AND ITS INVERTED TROUGH PINWHEELS ABOUT THE
INTERNATIONAL BORDER.

THERE IS ABUNDANT CLOUD COVER UPSTREAM...BUT IT IS MORE CELLULAR
IN NATURE...SO IT/S DIFFICULT TO SAY HOW MUCH CLEARING WILL OCCUR
OVERNIGHT...ESPECIALLY WHEN THE RAP 925 HPA RH SHOWS SATURATED
CONDITIONS THROUGH MONDAY MORNING. WILL SHOW SOME CLEARING WEST OF
THE VALLEY BY 12 UTC MONDAY...BUT THIS MAY BE OVERLY OPTIMISTIC.
EITHER WAY...WITH HIGHS THIS AFTERNOON IN THE 30S...NIGHTTIME
LOWS IN THE 20S SEEM REASONABLE.

BEST CHANCE FOR PRECIPITATION MONDAY WILL CONTINUE ACROSS THE LAKE
OF THE WOODS REGION WITH ALL OTHER AREAS DRY. SHOULD SEE A BIT
MORE SUN TO THE SOUTH AND WEST...BUT COLD AIR MASS WILL KEEP
HIGH TEMPERATURES IN THE 30S. NORTH-NORTHWEST WIND WILL PERSIST...
BUT WITH A WEAKENING PRESSURE GRADIENT...SHOULD BE A BIT LOWER
FROM 10 TO 15 MPH.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 316 PM CDT SUN OCT 20 2013

CANADIAN HIGH PRESSURE DIVES SOUTH ACROSS THE NORTHERN PLAINS
TUESDAY AND WEDNESDAY FOR MOSTLY DRY CONDITIONS. HOWEVER...
PERSISTENT CYCLONIC FLOW ALOFT COMBINED WITH HIGHER MID-LEVEL
MOISTURE WILL RESULT IN QUITE A BIT OF CLOUDS. MID-LEVEL THERMAL
RIDGE WILL NUDGE EASTWARD...ALLOWING FOR A LITTLE WARMING EACH
DAY...SO THAT HIGHS BY WEDNESDAY SHOULD APPROACH 40 DEGREES. THIS
IS STILL 10 TO 15 DEGREES BELOW MID-LATE OCTOBER NORMALS.

WED NIGHT-SUNDAY...NORTHWEST FLOW ALOFT THOUGH THE PERIOD. 12Z
MODELS ARE IN GOOD AGREEMENT INITIALLY...BUT QUICKLY DISAGREE WITH A
STRONGER WAVE FRIDAY INTO SUNDAY. THE GFS/GEM ARE MUCH QUICKER AND
FURTHER WEST WITH THIS WAVE THAN THE ECMWF. THE GFS/GEM BRING PRECIP
INTO NORTHWEST MINNESOTA WITH THIS FEATURE...WHILE THE ECMWF IS
BASICALLY DRY THROUGH THE PERIOD. TEMPERATURES WOULD ALSO BE
AFFECTED WITH EXACTLY WHERE THIS WAVE TRACKS. THE BLEND OF MODELS IS
LIKELY THE BEST COURSE OF ACTION.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 641 PM CDT SUN OCT 20 2013

ALL TAF SITES HAVE RISEN TO VFR CONDITIONS AND EXPECT CONDITIONS
TO CONTINUE THROUGH THE FORECAST PERIOD. WHETHER WE SCATTER OUT
WILL BE THE BIG QUESTION.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

UPDATE...VOELKER
SHORT TERM...ROGERS
LONG TERM...ROGERS/TG
AVIATION...VOELKER







AREA FORECAST DISCUSSION

NWS BISMARCK ND

 1242 AM CDT SAT OCT 19 2013

.UPDATE...
ISSUED AT 1242 AM CDT SAT OCT 19 2013

MAIN FOCUS ON THIS UPDATE WAS RAIN/SNOW CHANCES.

LATEST RADAR TRENDS CONTINUE TO SHOW ISOLATED SHOWERS ACROSS
WESTERN AND CENTRAL NORTH DAKOTA. SHOWERS WILL REMAIN ISOLATED
ACROSS EASTERN AND CENTRAL NORTH DAKOTA AS THE AREA REMAINS IN THE
FAVORED RIGHT ENTRANCE REGION OF AN UPPER LEVEL JET. SHOWERS WILL
COME TO AND END ACROSS CENTRAL NORTH DAKOTA EARLY SATURDAY MORNING
AS THE JET EXITS. WARM AIR ADVECTION AND WEAK ISENTROPIC ASCENT
MAY SPARK SOME ADDITIONAL SHOWERS IN WESTERN NORTH DAKOTA SATURDAY
MORNING.

THEREFORE...UPDATED PRECIP CHANCES TO REFLECT THE LATEST TRENDS
AND FORECAST GUIDANCE.

UPDATE ISSUED AT 903 PM CDT FRI OCT 18 2013

THE LATEST HRRR AND RAP13 PRECIPITATION FIELDS OVERALL FIT THE
CURRENT RADAR IMAGERY THIS EVENING. SHORTWAVE NOW INTO FAR NORTH
CENTRAL NORTH DAKOTA PER LATEST WATER VAPOR LOOP IN COMBINATION
WITH THE LEFT EXIT REGION OF A 100KT H3 JET STREAK CONTINUES TO
PROVIDE THE VERTICAL MOTION FOR PRODUCING SCATTERED SHOWERS. THIS
WILL GRADUALLY SHIFT FURTHER SOUTH AND EAST OVERNIGHT...WITH THE
PRECIPITATION EXITING THE JAMES RIVER VALLEY BY AROUND 09Z
SATURDAY. ATTENTION THEN TURNS TO THE NORTHWEST WHERE WARM AIR
ADVECTION ASSOCIATED WITH A WARM FRONTAL BOUNDARY BEGINS TO
IMPINGE FROM SOUTHERN CANADA INTO NORTHWEST AND NORTH CENTRAL
NORTH DAKOTA. ISENTROPIC LIFT PER 00Z NAM WILL LIKELY LEAD TO
ISOLATED RAIN OR SNOW SHOWERS BETWEEN 12Z AND 18Z SATURDAY IN THE
ABOVE MENTIONED AREA. THE CURRENT FORECAST HAS THIS FORECAST
ALREADY IN PLACE.

UPDATE ISSUED AT 524 PM CDT FRI OCT 18 2013

LATEST WATER VAPOR SHOWS A SHORTWAVE ALONG THE SOUTHERN SASKATCHEWAN
AND MANITOBA BORDER DIVING SOUTH WITH TIME. AN AREA OF VERTICAL
MOTION/H85-H3 OMEGA AHEAD OF THIS WAVE CONTINUES TO RESULT IN
SURFACE PRESSURE FALLS AND SCATTERED RAIN SHOWERS IN NORTH CENTRAL
NORTH DAKOTA. THE LATEST HRRR FORECASTS THIS AREA TO SHIFT SOUTH
AND INCREASE IN AREAL COVERAGE FOR SOUTH CENTRAL NORTH DAKOTA
THROUGH 04Z. CONCUR WITH THIS IDEA PER LATEST RADAR RETURNS. THERE
COULD BE SOME SNOW OR GRAPPLE WITHIN HEAVIER CONVECTIVE SHOWERS
THIS EVENING AS THE SHALLOW SURFACE WARM LAYER COOLS WITH SUPERCOOLED
WATER DROPLETS DOMINATING ABOVE. MAIN FORECAST REMAINS ON TRACK
WITH MINOR UPDATES TO HOURLY GRIDDED DATA.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 251 PM CDT FRI OCT 18 2013

SMALL POCKETS OF LIGHT RAIN WILL CONTINUE TO DEVELOP AND PUSH
SOUTHEAST THROUGH THE AFTERNOON HOURS. THE HIGHEST PRECIPITATION
COVERAGE IS EXPECTED NORTHEAST OF A LINE FROM KENMARE TO BISMARCK AND
ELLENDALE. AS NEAR SURFACE TEMPS DROP OFF TONIGHT...EXPECT RAIN TO
BECOME MIXED WITH OR CHANGE OVER TO ALL SNOW. THERE MAY BE SOME
VERY MINOR ACCUMULATIONS ON GRASSY SURFACES...MAINLY FROM
BOTTINEAU...TO CARRINGTON AND JAMESTOWN.

ON SATURDAY...A WARM FRONT WILL PUSH INTO WESTERN NORTH DAKOTA
DURING THE MORNING HOURS. A BAROCLINIC ZONE NEAR THE BOUNDARY MAY
BE ENOUGH TO SUPPORT A FEW LIGHT SNOW SHOWERS...MAINLY DURING THE
MORNING HOURS. AGAIN...LITTLE OR NO ACCUMULATION IS EXPECTED.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 251 PM CDT FRI OCT 18 2013

THE LONG TERM FORECAST WILL BE DOMINATED BY NORTH/NORTHWEST FLOW
ALOFT WITH A TROUGH OVER EASTERN CANADA/US AND A WESTERN RIDGE OVER
WESTERN CANADA/US.

THE MAIN FOCUS IN THE LONG TERM WILL BE SNOW AMOUNTS IN THE
NORTHEAST PART OF THE FORECAST AREA...BOTTINEAU-ROLLA-RUGBY-HARVEY
LATE SATURDAY NIGHT INTO SUNDAY MORNING. OTHER THAN THAT THERE WILL
BE A CHANCE OF LIGHT PRECIPITATION MONDAY/MONDAY NIGHT.

REGARDING THIS SATURDAY NIGHT/SUNDAY CLIPPER EVENT...TODAY`S MODELS
ARE INDICATING WARM AIR ADVECTION AHEAD OF THE SURFACE CLIPPER -
ENOUGH SUCH THAT PRECIPITATION SATURDAY EVENING AND INTO VERY EARLY
SUNDAY MORNING WOULD BE AHEAD AND EAST OF THE SURFACE LOW AND IN THE
FORM OF RAIN. RAIN WOULD NOT BE CHANGING TO SNOW UNTIL ROUGHLY 3 AM
IN THE TURTLE MOUNTAINS...THOUGH FARTHER WEST THE CHANGE TO SNOW MAY
OCCUR AROUND MIDNIGHT SATURDAY NIGHT. A GOOD AMOUNT OF THE
PRECIPITATION ASSOCIATED WITH THIS SYSTEM IS PROGGED TO BEGIN LATE
AFTERNOON/EARLY EVENING...WITH THE BEST LIFT AND MORE INTENSE
PRECIPITATION OCCURRING BEFORE MIDNIGHT. THE SURFACE LOW IS PROGGED
TO MOVE SOUTH FROM SASKATCHEWAN AND CROSS THE NORTH DAKOTA BORDER
BETWEEN 10 PM AND MIDNIGHT. THUS THE BULK OF THE ASSOCIATED
PRECIPITATION SHOULD BE IN THE FORM OF RAIN.

REGARDING SNOW AMOUNTS...THE LATEST EXPECTATION IS THAT THE TURTLE
MOUNTAINS MAY RECEIVE UP TO 2 INCHES OF SNOW FROM SATURDAY NIGHT
THROUGH SUNDAY...WITH HALF AN INCH TO AN INCH IN THE SURROUNDING
AREAS FROM BOTTINEAU TO NORTHERN MCHENRY TO PIERCE COUNTIES. LESSER
AMOUNTS EXPECTED ACROSS NORTHWESTERN NORTH DAKOTA TO THE NORTHERN
JAMES RIVER VALLEY.

WINDY AS WELL SATURDAY NIGHT AND SUNDAY AS THE CLIPPER LOW MOVES
FROM THE NORTH CENTRAL TO SOUTHEASTERN NORTH DAKOTA. NORTHWEST WINDS
OF 20 TO 30 MPH EARLY SUNDAY MORNING IN THE WEST...AND DAYTIME
SUNDAY OVER WESTERN AND CENTRAL NORTH DAKOTA.

A NEXT WEAKER WAVE IS THROUGH ON MONDAY / TUESDAY...FOLLOWED BY THE
BUILDING H5 RIDGE WITH DRIER AND MORE SEASONAL TEMPERATURES. THE
REST OF THE LONG TERM WILL SEE HIGHS IN THE 30S AND 40S OVER CENTRAL
NORTH DAKOTA...AND 40S TO LOWER 50S OVER WESTERN NORTH DAKOTA.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1242 AM CDT SAT OCT 19 2013

ISOLATED RAIN/SNOW SHOWERS AND VFR TO MVFR CIGS ARE EXPECTED FOR
THE NEXT 24 HOURS. EARLY SATURDAY MORNING...IT APPEARS KBIS/KJMS
WILL HAVE THE HIGHEST PROBABILITY FOR SHOWERS WITH KISN AND KMOT
SEEING THE BEST CHANCE LATE MORNING. CIGS WILL LIFT TO VFR AND
WINDS WILL SHIFT BRIEFLY OUT OF THE SOUTH SATURDAY AFTERNOON AS
A WARM FRONT MOVES THROUGH CENTRAL NORTH DAKOTA.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...AJ
SHORT TERM...RP KINNEY
LONG TERM...JV
AVIATION...AJ







AREA FORECAST DISCUSSION

NWS CLEVELAND OH

 952 AM EDT SAT OCT 19 2013

.SYNOPSIS...
A COLD FRONT HAS STALLED OVER NORTHERN OHIO AS WE AWAIT AN AREA
OF LOW PRESSURE TO MOVE NORTHWARD ALONG IT. THE LOW SHOULD MOVE
EAST OF THE AREA THIS AFTERNOON AND WILL DRAG THE FRONT INTO
CENTRAL PENNSYLVANIA THIS EVENING. HIGH PRESSURE WILL BRIEFLY
BUILD IN ON SUNDAY BEFORE THE NEXT COLD FRONT MOVES INTO THE AREA
ON MONDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...ADJUSTED MOST GRIDS THROUGH THE DAY HOWEVER MOST CHANGES
WERE MINOR DUE TO TIMING CHANGES. ALSO ADJUSTED HOURLY AND MAX
TEMPS TOWARD THE HRRR HOWEVER LIMITED HIGHS TO UPPER 50S EAST
WHICH WAS LOWER THAN THE HRRR GUIDANCE. BELIEVE RAIN WILL LIMIT
HIGHS.

ORIGINAL...RAIN IS MOVING INTO WESTERN OHIO WITH SPRINKLES TO A
HUNDREDTH OF AN INCH FROM DAYTON TO FORT WAYNE AS OF 10Z. RADAR
INDICATES THAT IT IS A BIT FURTHER EAST AND MAY SEE LIGHT RAIN AT
FINDLAY AND MARION SHORTLY. SO WITH THESE RADAR TRENDS WE HAVE
NUDGED THE ONSET OF RAIN BY A COUPLE HOURS FROM EARLIER THINKING.

PREVIOUS DISCUSSION...
A COLD FRONT HAS STALLED OVER THE AREA AS WE AWAIT A RIPPLE OF
LOW PRESSURE TO MOVE NORTHWARD ALONG IT. THIS BOUNDARY COMBINED
WITH IMPROVING LIFT ASSOCIATED WITH A 5H JET SHOULD BRING
INCREASING CHANCES OF RAIN. THE RAIN WILL REACH THE SOUTHWESTERN
COUNTY WARNING AREA SHORTLY AFTER SUNRISE AND THEN SPREAD EASTWARD
INTO THE AFTERNOON. THE RAIN MAY NOT REACH THE OH/PA BORDER UNTIL
MID AFTERNOON. AFTER THE RAIN BEGINS IT WILL LIKELY PERSIST FOR 6
TO 8 HOURS. RAINFALL AMOUNTS WILL LIKELY BE AROUND A THIRD OF AN
INCH OR SO.

CLOUD COVER AND THE RAINFALL WILL MAKE IT A COOL DAY WITH HIGHS
GENERALLY WITHIN A COUPLE DEGREES OF 50...SLIGHTLY WARMER ACROSS
EXTREME EASTERN OHIO INTO NW PA.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
RAINFALL WILL CONTINUE INTO THE EVENING ACROSS THE EASTERN COUNTY
WARNING AREA BUT SHOULD BECOME FOCUSED DOWNWIND OF LAKE ERIE
AFTER SUNSET. A SOUTHWEST TO WEST WIND SHOULD FOCUS THE SHOWERS
INTO EXTREME NE OHIO INTO NW PA THROUGH THE NIGHT. CLOUD COVER AND
A 10 TO 15 MPH BREEZE SHOULD KEEP FROST FROM DEVELOPING OVERNIGHT
AT MOST LOCATIONS EVEN WITH LOWS DIPPING INTO THE 30S. HOWEVER IF
ENOUGH BREAKS DEVELOP AND WINDS CAN DECOUPLE THERE WILL LIKELY BE
PATCHY FROST...ESPECIALLY ACROSS THE SOUTHWEST HALF OF THE REGION.
WILL MENTION THIS POTENTIAL IN THE HWO AND ALLOW THE NEXT SHIFT TO
EVALUATE THE POTENTIAL FOR A FROST ADVISORY.

DRIER AIR SHOULD ARRIVE ON SUNDAY WITH THE SHOWERS ENDING BY
EARLY AFTERNOON ACROSS NORTHERN ERIE COUNTY. HOWEVER WILL KEEP A
SLIGHT CHANCE GOING INTO THE AFTERNOON IF IT DOES NOT END AS EARLY
AS EXPECTED. THE CLOUD COVER FORECAST WILL BE DIFFICULT BUT
BELIEVE THEY WILL INCREASE DURING THE AFTERNOON UNDER THE BROAD
UPPER LEVEL TROUGH. THE CLOUDS WILL DEFINITELY RETURN SUNDAY NIGHT
AS THE NEXT PIECE OF ENERGY MOVES THROUGH THE UPPER TROUGH. SO
WITH THE EXTRA CLOUD COVER WE SHOULD SEE SLIGHTLY WARMER LOWS FOR
MONDAY MORNING.

RAIN CHANCES WILL ONCE AGAIN INCREASE MONDAY AFTERNOON INTO MONDAY
NIGHT. THE BEST CHANCES WILL BE ALONG A COLD FRONT THAT WILL SWEEP
ACROSS THE REGION FROM WEST TO EAST AFTER DARK. THIS FRONTAL
BOUNDARY WILL HAVE COOLER TEMPERATURES IN ITS WAKE THAN THE LAST
COUPLE. THE LAKE EFFECT SHOWERS THAT DEVELOP IN THE WAKE OF THE
FRONT MAY CHANGE TO SOME SNOW OVER THE INLAND HILLS OF NW PA
TUESDAY NIGHT. MORE ON THIS OVER THE NEXT COUPLE DAYS.

&&

.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
COOL UPPER TROUGH REMAINS OVER THE GREAT LAKES THROUGH FRIDAY. STILL
UNCERTAINTY IN THE SMALLER DETAILS OF INDIVIDUAL TROUGHS TO CROSS
THE LAKES. WILL HAVE TO KEEP CONTINUAL 30-50 PERCENT PRECIP CHANCES
FOR THE SNOWBELT THROUGH THE END OF THE WEEK. BETWEEN THE LAKE
EFFECT AND THE INDIVIDUAL TROUGHS...CANNOT PICK OUT THE DOWN TIMES
JUST YET. THERE MAY BE OPPORTUNITIES FOR PRECIP OUTSIDE OF THE
SNOWBELT WITH THE PASSAGE OF THE TROUGHS. BOUNDARY LAYER TEMPS WILL
REMAIN JUST WARM ENOUGH FOR PRECIP TO BE RAIN. EXCEPTION WOULD BE
FOR PRECIP FALLING DURING THE EARLY MORNING HOURS. TEMPERATURES WILL
REMAIN BELOW NORMAL WITH HIGHS ONLY IN THE UPPER 40S. NIGHT LOWS
WILL BE IN THE 30S...WITH WIDESPREAD LOWER 30S/FREEZING MORE LIKELY
TOWARD FRIDAY AS HIGH PRESSURE BEGINS TO BUILD OVER THE OHIO VALLEY.
ANY AMOUNT OF CLEARING ANY MORNING MAY RESULT IN TEMPS REACHING
FREEZING INLAND.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
RAIN BEGINNING TO MOVE INTO WESTERN OHIO ALONG WITH MVFR CEILINGS
AND VSBYS. EXPECT THIS AREA OF RAIN AND NON VFR CONDITIONS TO
OVERSPREAD THE REST OF NORTHERN OHIO THIS MORNING AND MAKE IT INTO
NW PA BY EARLY AFTERNOON. ONLY MINOR TIMING ADJUSTMENTS IN THIS
SET OF TAFS. OTHERWISE NON-VFR WEATHER WILL BE CONCENTRATED
BETWEEN NOW AND MID EVENING. EMBEDDED AREAS OF IFR POSSIBLE...BUT
OVERALL IT LOOKS TO BE A PREDOMINATELY MVFR EVENT. SSW FLOW
BECOMES MORE WSW BY THIS AFTERNOON. UNEVENTFUL AND VFR TONIGHT.

OUTLOOK...NON-VFR CIGS MAY RETURN FOR NW PA SUNDAY. OTHERWISE
EXPECT NON VFR FOR MONDAY NIGHT. CONTINUED INTERVALS OF NON VFR
CONDITIONS WILL BE POSSIBLE THROUGH WEDNESDAY...BUT MAINLY FOR FAR
NE OH/NW PA.

&&

.MARINE...
CHOPPY/ROUGH WEEK ON THE LAKE CONTINUES THROUGH THE WEEKEND AND INTO
NEXT WEEK. DIRECTION WILL VARY LITTLE...BETWEEN SSW AND WEST FOR THE
NEXT SEVERAL DAYS. WHILE THERE ARE A FEW LULLS IN THE WIND
SPEEDS...WIND WILL PREDOMINATELY RANGE FROM 10 TO 25 KNOTS.
THEREFORE WILL CONTINUE THE EASTERN TWO THIRDS SMALL CRAFT ADVISORY
AS IS. THE ISLANDS WILL NEED SMALL CRAFT ADVISORIES AT TIMES. ALL OF
THIS IS DUE TO A NUMBER OF FAST MOVING SYSTEMS COMING ACROSS THE
MIDWEST AND GREAT LAKES. WATERSPOUTS MAY ALSO BE POSSIBLE OVER
THE NEXT SEVERAL DAYS...BUT WILL NOT MENTION YET IN THE FORECAST
UNTIL CONDITIONS ARE MORE FAVORABLE AND AREAS OF CONVERGENCE CAN
BE PICKED OUT.

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EDT SUNDAY FOR LEZ146>149.

&&

$$
SYNOPSIS...MULLEN
NEAR TERM...TK/MULLEN
SHORT TERM...MULLEN
LONG TERM...OUDEMAN
AVIATION...OUDEMAN
MARINE...OUDEMAN







AREA FORECAST DISCUSSION

NWS TULSA OK

 932 PM CDT SUN OCT 20 2013

.DISCUSSION...
CLOUDINESS WILL BE ON THE INCREASE OVERNIGHT AS AN UPPER LEVEL
DISTURBANCE APPROACHES THE AREA FROM THE WEST AND A COLD FRONT
MOVES INTO NORTHEAST OKLAHOMA FROM THE NORTH. THERE IS A STRONG
SIGNAL IN RECENT RUNS OF THE HRRR THAT CONFIRMS THE 12Z ECMWF AND
UKMET SIGNALS THAT PRECIPITATION WILL BREAK OUT ACROSS PARTS OF
CENTRAL AND EASTERN OKLAHOMA OVERNIGHT. AS SUCH...WILL ADD POPS TO
AREAS SOUTHEAST OF INTERSTATE 44 LATER TONIGHT. WILL ALSO MAKE
SOME MINOR TEMPERATURES CHANGES.

UPDATE COMING SHORTLY.

&&

.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.

&&

$$

SHORT TERM...18
LONG TERM....05

PLATE






AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

 541 PM EDT SAT OCT 19 2013

.SYNOPSIS...
A COLD FRONT WILL PASS THROUGH THE REGION THIS EVENING FOLLOWED
BY A VISIT FROM HIGH PRESSURE ON SUNDAY AND MONDAY. THE PATTERN
WILL TURN NOTICEABLY COOLER AND UNSETTLED NEXT WEEK AS AN UPPER
TROUGH ESTABLISHES ITSELF OVER THE EASTERN UNITED STATES.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
EARLY EVENING REGIONAL RADAR LOOP SHOWING WIDESPREAD SHOWERS
FALLING ACROSS MOST OF CENTRAL PA...ALONG AXIS OF SOUTHERLY LL
JET/HIGHEST PWATS AHEAD OF APPROACHING COLD FRONT. FINE LINE OF
HIGHER RETURNS ALONG COLD FRONT NOTED ON THE OH/PA BORDER. AS CD
FRONT SWEEPS EAST...WOULDN/T BE SURPRISED TO SEE A COUPLE
LIGHTNING STRIKES ACROSS NORTH CENTRAL PA...WHERE NR TERM MDLS
PLACE SOME MARGINAL INSTABILITY.

LATEST RAP OUTPUT TIMES CDFRONT INTO THE W MTNS ARND 01Z AND
CLEARING THE EASTERNMOST COUNTIES /SCHUYLKILL AND LANCASTER/ BY
MIDNIGHT. WESTERLY FLOW OF MUCH DRIER AIR BEHIND THE FRONT WILL
SHUT OFF RAINFALL OVER NEARLY ALL OF THE AREA LATER THIS
EVENING...WITH THE POSSIBLE EXCEPTION OF THE NW MTNS...WHERE LAKE
EFFECT -SHRA COULD LINGER BEHIND FRONT. A MID-LAKE BAND WILL
PROBABLY DEVELOP ON GOOD INSTABILITY UNDER THE COLD AIR...AND WRLY
FLOW WILL MAKE IT JUST BRUSH AREAS N OF ROUTE 6 TONIGHT AND INTO
SUN MORNING.

CLEARING SHOULD TAKE PLACE OVER THE DOWNSLOPE AREAS OF THE CWA IN
THE POST-FRONTAL FLOW. THE INITIALLY GUSTY WEST WINDS WILL STAY UP
FOR MUCH OF THE NIGHT...BUT COULD SLACKEN IN THE DEEPER VALLEYS.
WILL LEAVE OUT MENTIONS OF VALLEY FOG AT THIS POINT WITH DEWPOINTS
FALLING INTO THE 30S AND WIND STILL GOING ALL NIGHT. BUT IT IS
TOUGH TO KEEP IT FROM FORMING WHEN AIR TEMP IS IN THE 30S AND
WATER MUCH WARMER.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
HIGH PRESSURE TO THE SOUTH OF THE STATE LOOKS VERY SIMILAR TO WHAT
THE PATTERN WAS ON FRIDAY. BUT...MUCH LESS MOISTURE AROUND...SO
THIS SHOULD LEAD TO MORE SUNSHINE. DIURNAL CU IS LIKELY OVER THE
HIGHER ELEVATIONS OF THE ALLEGHENIES...BUT COVERAGE SHOULD BE SCT
AT WORST. THE CLOUDS AND ANY SPRINKLES IN THE FAR NRN TIER SHOULD
LIFT TO THE NORTH THROUGH THE MORNING AND LEAVE A FAIR DAY THERE
AS WELL. WIND WILL INCREASE A BIT FROM ANY MORNING LULL AS THE
ATMOS MIXES. MAXES UNDER THE RATHER HOMOGENEOUS 0C-M2C 8H TEMPS
WILL BE ALMOST ENTIRELY DEPENDENT ON ELEVATION AND DOWNSLOPE
WARMING. THUS...MAXES CLOSE TO 50F IN THE NW MTS AND NEAR 60F IN
THE VALLEYS/LOWER ELEVS OF THE SUSQ VALLEY.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
CENTRAL PA WILL BE ON NORTHERN EDGE OF ERODING HIGH PRESSURE RIDGE
SUN NIGHT INTO MON...WITH A WARM FRONT LIFTING THROUGH OHIO VALLEY
AND SKIRTING W PA. THIS WILL KEEP WEATHER FAIR AND MILD...WITH
HIGHS MONDAY SLIPPING INTO THE 60S /ABOUT 4-8F ABOVE NORMAL/.

THINGS START TO GO DOWNHILL MONDAY NIGHT AS NEW ENERGY STARTS
DIVING OUT OF SOUTHERN CANADA ON THE WAY TO CARVING OUT A LARGE
SCALE PERSISTENT TROF OVER THE EASTERN U.S. A BUILDING RIDGE OVER
THE WEST COAST WILL HELP DEEPEN AN ADVANCING LOW...WHICH WILL
DELIVER A STEADY FEED OF INCREASINGLY MORE CHILLY AIR ACROSS THE
UPPER MIDWEST NEXT WEEK. THIS COLD AIR WILL PROPAGATE INTO THE
LOWER LAKES AND LOCAL AREA IN THE WAKE OF A COLD FRONTAL BOUNDARY
PROGGED FOR TUESDAY...AND REINFORCED BY SECONDARY TROUGH ON
WEDNESDAY /AS ANOTHER LOW FORMS ALONG THE BOUNDARY AND SLIDES
ACROSS MID ATLANTIC STATES JUST TO OUR SOUTH BEFORE SLIDING OFF
THE COAST OF NEW ENGLAND/.

SOME DIFFERENCES CONTINUE IN MODEL SOLUTIONS STARTING AROUND
WEDNESDAY WHEN THE ECMWF BRINGS A STRONG SHORTWAVE OUT OF THE
OHIO VALLEY. THE OPERATIONAL GFS AND THE GEFS /PREVIOUSLY WITH A
FLATTER TROUGH/ ARE COMING MORE IN LINE WITH THE EC...WHICH WILL
INCREASE OUR POP CHANCES FOR WED WITH A STEADY LIGHT RAIN POSS.

AFTER THAT...CYCLONIC FLOW WILL CONTINUE TO ALLOW INCREASINGLY
COOLER AIR TO FILTER IN ON NW FLOW. PLENTY OF COLD ADVECTION
STRATOCU AND LAKE/OROGRAPHIC SHOWERS LOOKING LIKELY IN THE HIGHER
WESTERN TERRAIN MID/LATE WEEK...WITH DOWNSLOPE COMPONENT TO WINDS
KEEPING PRECIP AT A MIN FOR THE SE. LOW LEVEL TEMPS GET COLD
ENOUGH /850MB TEMPS DIP BELOW 0C/ THAT LIGHT SHOWERS COULD BE
MIXED WITH WET SNOW DURING THE CHILLIEST PART OF THE DAY AND
OVERNIGHT.

HIGH PRESSURE BUILDS IN LOW LEVELS FOR THE WEEKEND...BRINGING
QUITE CHILLY MORNING TEMPS. BUT AN OVERALL MORE SETTLED WEATHER
PATTERN. REINFORCING SHOT OF COLDER AIR POSS EARLY NEXT WEEK.

&&

.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
EXCEPT FOR KUNV...ALL CENTRAL PA AIRFIELDS REPORTING VFR
CONDITIONS LATE THIS AFTERNOON...DESPITE A GOOD DEAL OF RAIN AND
SHOWERS MOVING THROUGH THE REGION. SURFACE ANALYSIS SHOWS A BAND
OF LOWER MVFR TO IFR CIGS WITH AND DIRECTLY BEHIND THE APPROACHING
COLD FRONT...SO HAVE INCLUDED THIS PERIOD OF LOWERING CIGS IN TAFS.

FROPA TIMED AT KBFD BETWEEN 23Z AND 00Z...IN CENTRAL AREAS SUCH AS
KUNV BETWEEN 01Z AND 02Z...AND ACROSS THE EASTERN AIRFIELDS
BETWEEN 03Z AND 04Z. AGAIN...DRAMATIC WIND SHIFT TO THE WEST...AND
A BAND OF LOWER CIGS WILL ACCOMPANY THE FRONT.

HIGH PRESSURE BUILDS TO THE WEST FROM THE TENNESSEE VALLEY...BUT
STAYS FAR ENOUGH AWAY TO KEEP SOME GRADIENT WIND...GENERALLY
10 TO 12 KTS...DURING THE DAY ON SUNDAY WITH OTHERWISE VFR
CONDITIONS. SHOWERS MAY LINGER LATE TONIGHT AND VERY EARLY SUN
A.M. VCTY BFD. BUT EVEN AT BFD IMPROVEMENT TO VFR WILL OCCUR IN
THE MORNING.

MONDAY LOOKS FAIR/VFR AS HIGH PRESSURE SLIDES TO THE EAST COAST
AND RETURN FLOW BEGINS. MORE COLD AIR ARRIVES WITH THE NEXT COLD
FRONT MON NIGHT AND TUESDAY.

OUTLOOK...
TUE...FROPA. MVFR/IFR POSS DUE TO SHOWERS/CLOUDS...ESP NW.
WED...MVFR POSS IN SHRA...ESP NW.
THURS...BREEZY...MVFR CLOUDS/SHRA N/W.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LA CORTE
NEAR TERM...DANGELO/FITZGERALD
SHORT TERM...DANGELO
LONG TERM...RXR
AVIATION...JUNG/DANGELO







AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

 519 PM EDT SAT OCT 19 2013

.SYNOPSIS...
A COLD FRONT WILL PASS THROUGH THE REGION THIS EVENING FOLLOWED
BY A VISIT FROM HIGH PRESSURE ON SUNDAY AND MONDAY. THE PATTERN
WILL TURN NOTICEABLY COOLER AND UNSETTLED NEXT WEEK AS AN UPPER
TROUGH ESTABLISHES ITSELF OVER THE EASTERN UNITED STATES.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
EARLY EVENING REGIONAL RADAR LOOP SHOWING WIDESPREAD SHOWERS
FALLING ACROSS MOST OF CENTRAL PA...ALONG AXIS OF SOUTHERLY LL
JET/HIGHEST PWATS AHEAD OF APPROACHING COLD FRONT. FINE LINE OF
HIGHER RETURNS ALONG COLD FRONT NOTED ON THE OH/PA BORDER. AS CD
FRONT SWEEPS EAST...WOULDN/T BE SURPRISED TO SEE A COUPLE
LIGHTNING STRIKES ACROSS NORTH CENTRAL PA...WHERE NR TERM MDLS
PLACE SOME MARGINAL INSTABILITY.

LATEST RAP OUTPUT TIMES CDFRONT INTO THE W MTNS ARND 01Z AND
CLEARING THE EASTERNMOST COUNTIES /SCHUYLKILL AND LANCASTER/ BY
MIDNIGHT. WESTERLY FLOW OF MUCH DRIER AIR BEHIND THE FRONT WILL
SHUT OFF RAINFALL OVER NEARLY ALL OF THE AREA LATER THIS
EVENING...WITH THE POSSIBLE EXCEPTION OF THE NW MTNS...WHERE LAKE
EFFECT -SHRA COULD LINGER BEHIND FRONT. A MID-LAKE BAND WILL
PROBABLY DEVELOP ON GOOD INSTABILITY UNDER THE COLD AIR...AND WRLY
FLOW WILL MAKE IT JUST BRUSH AREAS N OF ROUTE 6 TONIGHT AND INTO
SUN MORNING.

CLEARING SHOULD TAKE PLACE OVER THE DOWNSLOPE AREAS OF THE CWA IN
THE POST-FRONTAL FLOW. THE INITIALLY GUSTY WEST WINDS WILL STAY UP
FOR MUCH OF THE NIGHT...BUT COULD SLACKEN IN THE DEEPER VALLEYS.
WILL LEAVE OUT MENTIONS OF VALLEY FOG AT THIS POINT WITH DEWPOINTS
FALLING INTO THE 30S AND WIND STILL GOING ALL NIGHT. BUT IT IS
TOUGH TO KEEP IT FROM FORMING WHEN AIR TEMP IS IN THE 30S AND
WATER MUCH WARMER.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
HIGH PRESSURE TO THE SOUTH OF THE STATE LOOKS VERY SIMILAR TO WHAT
THE PATTERN WAS ON FRIDAY. BUT...MUCH LESS MOISTURE AROUND...SO
THIS SHOULD LEAD TO MORE SUNSHINE. DIURNAL CU IS LIKELY OVER THE
HIGHER ELEVATIONS OF THE ALLEGHENIES...BUT COVERAGE SHOULD BE SCT
AT WORST. THE CLOUDS AND ANY SPRINKLES IN THE FAR NRN TIER SHOULD
LIFT TO THE NORTH THROUGH THE MORNING AND LEAVE A FAIR DAY THERE
AS WELL. WIND WILL INCREASE A BIT FROM ANY MORNING LULL AS THE
ATMOS MIXES. MAXES UNDER THE RATHER HOMOGENEOUS 0C-M2C 8H TEMPS
WILL BE ALMOST ENTIRELY DEPENDENT ON ELEVATION AND DOWNSLOPE
WARMING. THUS...MAXES CLOSE TO 50F IN THE NW MTS AND NEAR 60F IN
THE VALLEYS/LOWER ELEVS OF THE SUSQ VALLEY.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
CENTRAL PA WILL BE ON NORTHERN EDGE OF ERODING HIGH PRESSURE RIDGE
SUN NIGHT INTO MON...WITH A WARM FRONT LIFTING THROUGH OHIO VALLEY
AND SKIRTING W PA. THIS WILL KEEP WEATHER FAIR AND MILD...WITH
HIGHS MONDAY SLIPPING INTO THE 60S /ABOUT 4-8F ABOVE NORMAL/.

THINGS START TO GO DOWNHILL MONDAY NIGHT AS NEW ENERGY STARTS
DIVING OUT OF SOUTHERN CANADA ON THE WAY TO CARVING OUT A LARGE
SCALE PERSISTENT TROF OVER THE EASTERN U.S. A BUILDING RIDGE OVER
THE WEST COAST WILL HELP DEEPEN AN ADVANCING LOW...WHICH WILL
DELIVER A STEADY FEED OF INCREASINGLY MORE CHILLY AIR ACROSS THE
UPPER MIDWEST NEXT WEEK. THIS COLD AIR WILL PROPAGATE INTO THE
LOWER LAKES AND LOCAL AREA IN THE WAKE OF A COLD FRONTAL BOUNDARY
PROGGED FOR TUESDAY...AND REINFORCED BY SECONDARY TROUGH ON
WEDNESDAY /AS ANOTHER LOW FORMS ALONG THE BOUNDARY AND SLIDES
ACROSS MID ATLANTIC STATES JUST TO OUR SOUTH BEFORE SLIDING OFF
THE COAST OF NEW ENGLAND/.

SOME DIFFERENCES CONTINUE IN MODEL SOLUTIONS STARTING AROUND
WEDNESDAY WHEN THE ECMWF BRINGS A STRONG SHORTWAVE OUT OF THE
OHIO VALLEY. THE OPERATIONAL GFS AND THE GEFS /PREVIOUSLY WITH A
FLATTER TROUGH/ ARE COMING MORE IN LINE WITH THE EC...WHICH WILL
INCREASE OUR POP CHANCES FOR WED WITH A STEADY LIGHT RAIN POSS.

AFTER THAT...CYCLONIC FLOW WILL CONTINUE TO ALLOW INCREASINGLY
COOLER AIR TO FILTER IN ON NW FLOW. PLENTY OF COLD ADVECTION
STRATOCU AND LAKE/OROGRAPHIC SHOWERS LOOKING LIKELY IN THE HIGHER
WESTERN TERRAIN MID/LATE WEEK...WITH DOWNSLOPE COMPONENT TO WINDS
KEEPING PRECIP AT A MIN FOR THE SE. LOW LEVEL TEMPS GET COLD
ENOUGH /850MB TEMPS DIP BELOW 0C/ THAT LIGHT SHOWERS COULD BE
MIXED WITH WET SNOW DURING THE CHILLIEST PART OF THE DAY AND
OVERNIGHT.

HIGH PRESSURE BUILDS IN LOW LEVELS FOR THE WEEKEND...BRINGING
QUITE CHILLY MORNING TEMPS. BUT AN OVERALL MORE SETTLED WEATHER
PATTERN. REINFORCING SHOT OF COLDER AIR POSS EARLY NEXT WEEK.

&&

.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
HIGHER-END MVFR CIGS AND LOWER-END VFR CIGS EXPECTED THIS EVENING
AS THE COLD FRONT AND ASSOCD SHOWERS PUSH THROUGH FROM W-E.
SHOWERS OVER THE CENTRAL MTS WILL BE THE MAIN STORY AND COULD MAKE
GUSTS INTO THE L20S AT THE EASTERN TERMINALS AS THEY COAGULATE IN
THE NEXT HOUR OR SO. THE LIGHT RAIN TO THE WEST OF THE AREA WILL
LIKELY BEGIN TO DISSIPATE AS IT REACHES A BFD-JST LINE. THE DRY
AIR AT THE SFC WILL MAKE IT EASY FOR THE HUSTY WINDS BEHIND THE
FRONT TO MIX DOWN EARLY TONIGHT...BUT SOME DECOUPLING IS POSSIBLE
IN THE DEEPER VALLEYS IN THE MORNING. CLOUDS SHOULD DECREASE
RAPIDLY TONIGHT OVER THE SERN HALF OF THE FORECAST AREA. HIGH
PRESSURE BUILDS TO THE WEST FROM THE TN VALLEY...BUT STAYS FAR
ENOUGH AWAY TO KEEP SOME GRADIENT WIND - GENERALLY 10-12 KTS
DURING THE DAY ON SUNDAY WITH OTHERWISE VFR CONDITIONS. SHOWERS
MAY LINGER LATE TONIGHT AND VERY EARLY SUN A.M. VCTY BFD. BUT EVEN
AT BFD IMPROVEMENT TO VFR WILL OCCUR IN THE MORNING.

MONDAY LOOKS FAIR/VFR AS HIGH PRESSURE SLIDES TO THE EAST COAST
AND RETURN FLOW BEGINS. MORE COLD AIR ARRIVES WITH THE NEXT COLD
FRONT MON NIGHT AND TUESDAY.

OUTLOOK...
TUE...FROPA. MVFR/IFR POSS DUE TO SHOWERS/CLOUDS...ESP NW.
WED...MVFR POSS IN SHRA...ESP NW.
THURS...BREEZY...MVFR CLOUDS/SHRA N/W.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LA CORTE
NEAR TERM...DANGELO/FITZGERALD
SHORT TERM...DANGELO
LONG TERM...RXR
AVIATION...DANGELO







AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

 253 PM EDT SAT OCT 19 2013

.SYNOPSIS...
A COLD FRONT WILL PASS THROUGH THE REGION THIS EVENING FOLLOWED
BY A VISIT FROM HIGH PRESSURE ON SUNDAY AND MONDAY. THE PATTERN
WILL TURN NOTICEABLY COOLER AND UNSETTLED NEXT WEEK AS AN UPPER
TROUGH ESTABLISHES ITSELF OVER THE EASTERN UNITED STATES.

&&

.NEAR TERM /THROUGH TONIGHT/...
DRY AIR SEEMS TO BE WINNING OUT AT THIS POINT...AND LITTLE PRECIP
HAS FALLEN. DEWPOINTS HAVE NOT RISEN PAST THE M40S. LITTLE
MOISTURE AVAILABLE...BUT LOWER ATMOS IS TRYING TO MOISTEN UP.
EXPECT THE SHOWERS OVER THE CENTRAL MTS TO CONTINUE DEVELOPING IN
THE IDEA OF THE HRRR AND RUC RUNS OF THE LAST FEW HRS.
THUS...THESE SHOULD BE THE MOST NUMEROUS SHOWERS AND MOVE TO THE
EAST THROUGH THE VERY EARLY EVENING. THESE SHOWERS SHOULD BE OFF
TO THE EAST OF THE CWA BY 8 PM. THE RAIN OVER NRN OH AND FAR WRN
PA IS FEEDING ON POOR DEWPOINTS AS WELL. WILL PAINT THE HIGHEST
POPS IN THE NW AND ALSO FROM UNV TO THE EAST. JUST SCT SHOWERS
WILL BE LEFT ALONG THE NY BORDER AND PERHAPS IN THE LAURELS FOR
THE EARLY PART OF THE NIGHT. A MID-LAKE BAND WILL PROBABLY DEVELOP
ON GOOD INSTABILITY UNDER THE COLD AIR...AND WRLY FLOW WILL MAKE
IT JUST BRUSH AREAS N OF ROUTE 6 TONIGHT AND INTO SUN MORNING.
CLEARING SHOULD TAKE PLACE OVER THE DOWNSLOPE AREAS OF THE CWA IN
THE POST-FRONTAL FLOW. THE INITIALLY GUSTY WEST WINDS WILL STAY
UP FOR MUCH OF THE NIGHT...BUT COULD SLACKEN IN THE DEEPER
VALLEYS. WILL LEAVE OUT MENTIONS OF VALLEY FOG AT THIS POINT WITH
DEWPOINTS FALLING INTO THE 30S AND WIND STILL GOING ALL NIGHT. BUT
IT IS TOUGH TO KEEP IT FROM FORMING WHEN AIR TEMP IS IN THE 30S
AND WATER MUCH WARMER.

&&

.SHORT TERM /SUNDAY/...
HIGH PRESSURE TO THE SOUTH OF THE STATE LOOKS VERY SIMILAR TO WHAT
THE PATTERN WAS ON FRIDAY. BUT...MUCH LESS MOISTURE AROUND...SO
THIS SHOULD LEAD TO MORE SUNSHINE. DIURNAL CU IS LIKELY OVER THE
HIGHER ELEVATIONS OF THE ALLEGHENIES...BUT COVERAGE SHOULD BE SCT
AT WORST. THE CLOUDS AND ANY SPRINKLES IN THE FAR NRN TIER SHOULD
LIFT TO THE NORTH THROUGH THE MORNING AND LEAVE A FAIR DAY THERE
AS WELL. WIND WILL INCREASE A BIT FROM ANY MORNING LULL AS THE
ATMOS MIXES. MAXES UNDER THE RATHER HOMOGENEOUS 0C-M2C 8H TEMPS
WILL BE ALMOST ENTIRELY DEPENDENT ON ELEVATION AND DOWNSLOPE
WARMING. THUS...MAXES CLOSE TO 50F IN THE NW MTS AND NEAR 60F IN
THE VALLEYS/LOWER ELEVS OF THE SUSQ VALLEY.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
MONDAY WILL BEGIN THE EXTENDED ON THE FAIR AND MILD SIDE AS THE
HIGH REMAINS IN CONTROL FOR ONE MORE DAY. THINGS START TO GO
DOWNHILL MONDAY NIGHT AS NEW ENERGY STARTS DIVING OUT OF SOUTHERN
CANADA ON THE WAY TO CARVING OUT A LARGE SCALE TROF OVER THE
EASTERN US.

THE BUILDING RIDGE OVER THE WEST COAST...AIDED BY A STRONG
TYPHOON THAT PASSED EAST OF JAPAN SEVERAL DAYS AGO...WILL HELP
DEEPEN AN ADVANCING LOW WHICH WILL DELIVER INCREASINGLY CHILLY
AIR THROUGH THE UPPER MID WEST NEXT WEEK. THIS COLD AIR WILL
PROPAGATE INTO THE LOWER LAKES AND LOCAL AREA BY THE TUESDAY-
WEDNESDAY TIME FRAME.

DIFFERENCES ARISE IN THE PATTERN AROUND WEDNESDAY WHEN THE
ECMWF...FOR THE SECOND RUN IN A ROW SHOWS A STRONG SHORTWAVE
MOVING OUT OF THE OHIO VALLEY. THE OPERATIONAL GFS AND THE GEFS
HAVE A TROF...BUT FLATTER AND MUCH MORE POSITIVELY TILTED. THE
ECMWF EVENTUALLY USES ITS POTENT WAVE TO DEVELOP A COASTAL LOW
THAT BRINGS AN EARLY SEASON NOR`EASTER TO NEW ENGLAND AND THE
MARITIMES...WHILE THE GFS/GEFS JUST KEEPS US IN GENERALLY COOL
AND CYCLONIC UPPER FLOW WHICH AT THIS TIME OF YEAR STARTS TO
MEAN PLENTY OF COLD ADVECTION STRATOCU AND LAKE/OROGRAPHIC
SHOWERS LOOKING LIKELY. THE MAIN DIFFERENCE LOCALLY GIVEN THE
MODEL DIFFERENCES WOULD BE FOR A BETTER CHANCE OF MORE
WIDESPREAD SHOWERS WEDNESDAY INTO WEDNESDAY NIGHT.

STARTING TUESDAY NIGHT...AND LASTING THROUGH THE WEEK...ALL
GUIDANCE AGREES THAT ENOUGH COLD AIR WILL HAVE MOVED INTO THE
REGION THAT ANY OF THE LIGHT SHOWERS THAT FALL COULD BE MIXED
WITH SNOW DURING THE CHILLIEST PART OF THE DAY AND OVERNIGHT.
ACCUMULATIONS WILL BE LIGHT IF ANY...BUT IT`S ALL POINTING TO
IT BEING DOWNHILL TO WINTER FROM HERE.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
HIGHER-END MVFR CIGS AND LOWER-END VFR CIGS EXPECTED THIS EVENING
AS THE COLD FRONT AND ASSOCD SHOWERS PUSH THROUGH FROM W-E.
SHOWERS OVER THE CENTRAL MTS WILL BE THE MAIN STORY AND COULD MAKE
GUSTS INTO THE L20S AT THE EASTERN TERMINALS AS THEY COAGULATE IN
THE NEXT HOUR OR SO. THE LIGHT RAIN TO THE WEST OF THE AREA WILL
LIKELY BEGIN TO DISSIPATE AS IT REACHES A BFD-JST LINE. THE DRY
AIR AT THE SFC WILL MAKE IT EASY FOR THE HUSTY WINDS BEHIND THE
FRONT TO MIX DOWN EARLY TONIGHT...BUT SOME DECOUPLING IS POSSIBLE
IN THE DEEPER VALLEYS IN THE MORNING. CLOUDS SHOULD DECREASE
RAPIDLY TONIGHT OVER THE SERN HALF OF THE FORECAST AREA. HIGH
PRESSURE BUILDS TO THE WEST FROM THE TN VALLEY...BUT STAYS FAR
ENOUGH AWAY TO KEEP SOME GRADIENT WIND - GENERALLY 10-12 KTS
DURING THE DAY ON SUNDAY WITH OTHERWISE VFR CONDITIONS. SHOWERS
MAY LINGER LATE TONIGHT AND VERY EARLY SUN A.M. VCTY BFD. BUT EVEN
AT BFD IMPROVEMENT TO VFR WILL OCCUR IN THE MORNING.

MONDAY LOOKS FAIR/VFR AS HIGH PRESSURE SLIDES TO THE EAST COAST
AND RETURN FLOW BEGINS. MORE COLD AIR ARRIVES WITH THE NEXT COLD
FRONT MON NIGHT AND TUESDAY.

OUTLOOK...
TUE...FROPA. MVFR/IFR POSS DUE TO SHOWERS/CLOUDS...ESP NW.
WED...MVFR POSS IN SHRA...ESP NW.
THURS...BREEZY...MVFR CLOUDS/SHRA N/W.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LA CORTE
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...LA CORTE
AVIATION...DANGELO










AREA FORECAST DISCUSSION

NWS HOUSTON/GALVESTON TX

 1230 PM CDT SAT OCT 19 2013

.DISCUSSION...
18Z AVIATION DISCUSSION BELOW.

&&

.AVIATION...
VFR IN THIS POST-FRONTAL ENVIRONMENT. AREAWIDE SKY CLEAR BY
19-20Z AND WEAKENING NORTHERLIES TO VRB03KT/CALM SHORTLY AFTER
SUNSET. LIGHT BREEZE WAKES UP FROM THE EAST LATE SUNDAY MORNING
...A GRADUAL LATE SUNDAY AFTERNOON VEERING TO MORE ONSHORE WITH
A MID-LEVEL CLOUD DECK BY 00Z MONDAY. 31

&&

.PREV DISCUSSION... /ISSUED 1039 AM CDT SAT OCT 19 2013/

UPDATE...
SEE MORNING UPDATE.

DISCUSSION...
A COLD FRONT HAS CLEARED THE COAST AND SIGNIFICANTLY COOLER
TEMPERATURES AND DRIER AIR ARE FILTERING INTO SOUTHEAST TEXAS.
GRADIENT REMAINS RATHER TIGHT AND SO AM EXPECTING BREEZY CONDS TO
PERSIST. BETWEEN COLD AIR ADVECTION AND MIXING...AM NOT SURE THAT
THEY`LL BE MUCH OF A WARM UP TODAY DESPITE FULL SUNSHINE EXPECTED
THIS AFTN. TWEAKED MAX TEMPS A BIT LOWER OVER THE NORTH. TWEAKED
SKY GRIDS A BIT TO REFLECT RAPID CLEARING OVER THE NORTHERN ZONES.
THE CHANGES ARE VERY MINOR AND THE INTEGRITY OF THE PREVIOUS FCST
IS UNCHANGED AND ON TRACK. 43

&&

PREV DISCUSSION... /ISSUED 631 AM CDT SAT OCT 19 2013/

UPDATE...
EARLY MORNING UPDATE FOR RAIN MOVING OUT OF THE AREA.

DISCUSSION...
KEEPING UP WITH LATEST RADAR TRENDS HAVE UPDATED RAIN CHANCES FOR
THE DAY AS PRECIP CONTINUES TO MOVE EAST OUT INTO THE GULF. LOOKS
LIKE MOSTLY CLOUDY SKIES TO START THIS MORNING AS COLD FRONT
PUSHES THROUGH THE AREA. COLD FRONT CURRENTLY PUSHING THROUGH
CONROE AND APPROACHING THE HOUSTON AREA. FRONT SHOULD PUSH OFF THE
COAST MID MORNING. UPDATED FORECAST PRODUCTS HAVE BEEN ISSUED. 39

&&

PREV DISCUSSION... /ISSUED 608 AM CDT SAT OCT 19 2013/

DISCUSSION...
SEE AVIATION FOR 12Z TAF DISCUSSION

AVIATION...
SHRA HAVE MOVED OFFSHORE THIS MORNING AND ALL PRECIP MENTIONS WILL
BE REMOVED FROM THE TAFS. NORTHERLY WINDS ALREADY ONGOING AT ALL
SITES AS PREFRONTAL TROUGH HAS PUSHED OFFSHORE WITH THE ACTUAL
COLD FRONT HAVING REACHED CLL AND UTS THIS MORNING. EXPECT AN HOUR
OR TWO WITH GUSTS NEAR 20KTS AS THE FRONTAL BOUNDARY PUSHES
THROUGH THIS MORNING. MAIN CONCERN WILL BE SOUTHERLY EXTENT OF
IFR/MVFR CIGS IMMEDIATELY BEHIND THE FRONT. AS THE SUN COMES UP
THIS MORNING FEEL THAT THIS LAYER WILL BEGIN TO SCATTER OUT SO
HAVE NOT INCLUDED CIGS FOR IAH ALTHOUGH A BRIEF PERIOD OF
BKN010-BKN015 IS POSSIBLE THIS MORNING BEFORE CONDITIONS IMPROVE
TO VFR BY AFTERNOON. SURFACE HIGH PRESSURE WILL SPREAD INTO
SOUTHEAST TEXAS SATURDAY EVENING LEADING TO VARIABLE WINDS ACROSS
THE INLAND AREAS OVERNIGHT INTO SUNDAY. 38

&&

PREV DISCUSSION... /ISSUED 428 AM CDT SAT OCT 19 2013/

DISCUSSION...
COLD FRONT PUSHING SOUTH THROUGH TEXAS AT 09Z (4AM CDT) ABOUT AT
A KLFK/KUTS/K11R LINE OR BASICALLY A BRENHAM TO LUFKIN LINE. LINE
OF SHOWERS AND THUNDERSTORMS OVER HOUSTON EARLIER TONIGHT HAS
WEAKENED AND ACTIVITY HAS INCREASED MORE OFF THE UPPER TX COAST.
UPPER LEVEL SHORT WAVE LOOKS TO BE MOVING OUT OF THE AREA AND
POSSIBLE THAT UPPER LEVEL DIVERGENCE IS WEAKENING AS A RESULT.
BULK OF EARLIER CONVECTION HAS BEEN SUPPORTED BY SOME ISENTROPIC
LIFT AND FRONTOGENESIS IN 925-850MB LAYER PER SPC MESOANALYSES.
PER LATEST RADAR TRENDS...EXPECT SOME LINGERING SHOWERS ALONG THE
COAST BUT LOOKS LIKE MOST OF THE RAINFALL MAY BE DONE BY 12Z WHICH
IS A GOOD 3-6 HRS SOONER THAN MOST 00Z MODEL SOLUTIONS. HOWEVER
THE 00Z TX TECH 3KM WRF AND LATEST 06Z HRRR ARE IN GOOD AGREEMENT
WITH LATEST TRENDS. FORECAST HAS BE TRENDED TOWARDS THESE MODELS
IN THE SHORT TERM BUT MAY HOLD ONTO PRECIP A LITTLE LONGER. COLD
FRONT SHOULD BE OFF THE COAST BETWEEN 12-15Z THIS MORNING WITH
STRONG NORTHERLY WINDS ARE WIDE. UPPER LEVEL TROUGH AXIS WILL ALSO
HAVE PUSHED BY SE TX WITH RIGHT REAR QUADRANT OF JET STREAK STILL
LINGERING OVER THE AREA. HIGH PRESSURE AT THE SURFACE SHOULD
CONTINUE TO BUILD OVER TX TODAY. MAX TEMPS WILL BE A CHALLENGE AS
DO EXPECT SOME COLD ADVECTION TO OCCUR. HOWEVER 850MB TEMPS ONLY
DROP TO ABOUT 12-13C SO COULD STILL SEE TEMPS REACHING UPPER 60S
TO LOW 70S WITH DAYTIME HEATING. CLOUD COVER SHOULD CLEAR OUT SO
MAY NOT GET QUITE AS COOL AS IT COULD WITH BULK OF COLDER AIRMASS
MOVING EAST OF THE AREA OVER MISS RIVER VALLEY.

LOOKS LIKE RETURN FLOW AND WARM ADVECTION WILL ENSUE ONCE AGAIN
SUN NIGHT INTO MONDAY. VERY SIMILAR SET UP TO THE MOST RECENT RAIN
EVENT WITH WEAK ISENTROPIC LIFT AND A SHORT WAVE TROUGH ROTATING
THROUGH THE S PLAINS PROVIDING ENOUGH LARGE SCALE ASCENT FOR
ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. THINK ORIENTATION OF
JET STREAK AND SHORT WAVE TROUGH MAY PUSH BULK OF PRECIP EAST OF
SE TX SO HAVE NOT CHANGED POPS MUCH. BEST CHANCES WILL AGAIN BE
ALONG THE COAST BUT WILL KEEP AROUND 50 PERCENT FOR NOW. ANOTHER
COLD FRONT WILL ALSO PUSH INTO SE TX BUT MORE SO MON NIGHT INTO
TUE MORNING. BEST LIFT WILL HAVE SHIFTED EAST BY THIS TIME SO WILL
BE HAVING DECREASING RAIN CHANCES MON NIGHT INTO TUE.

TUE THROUGH THE REST OF THE WEEK SHOULD BE DRY WITH A RATHER
AMPLIFIED UPPER LEVEL PATTERN. BROAD RIDGE SHOULD REMAIN OVER THE
PACIFIC COAST WITH A DEEP LOW AND LONG WAVE TROUGH OVER THE GREAT
LAKES AND MIDWEST. SEVERAL SHORT WAVE TROUGHS MOVING THROUGH THE
FLOW SHOULD KEEP THE TROUGH OVER THE GREAT LAKES THROUGH THE END
OF THE WEEK. WILL GET SFC HIGH PRESSURE BUILDING OVER TX THROUGH
WED WITH ANOTHER RIDGE BUILDING OVER THE MIDWEST THUR INTO FRI.
PATTERN SHOULD KEEP CONDITIONS DRY AND ON THE COOL SIDE. TRIED TO
BLEND THE TEMP FORECAST BETWEEN GFS AND ENSEMBLE MEAN TEMPS FOR
THE LATER HALF OF THE WEEK. THIS WILL MEAN TEMPS WILL BE NEAR OR
EVEN A DEGREE OR TWO BELOW NORMAL FOR THE END OF NEXT WEEK. 39

&&

MARINE...
NORTHERLY WINDS HAVE REACHED THE NEARSHORE BUOY THIS MORNING AS A
PREFRONTAL TROUGH PUSHES OUT AHEAD OF THE COLD FRONT MOVING INTO
SOUTHEAST TEXAS. EXPECT OFFSHORE WINDS TO PICK UP THROUGH THE
MORNING WITH BUILDING SEAS AS THE FRONT MOVES OFFSHORE. ADVISORY
FLAGS IN PLACE ACROSS ALL COASTAL WATERS TODAY AND MAY NEED TO BE
EXTENDED FURTHER STILL...ALTHOUGH WILL ALLOW NEXT SHIFT TO
EVALUATE NEW MODEL DATA AND OBSERVATIONS FROM TODAY BEFORE MAKING
THAT DECISION. EXPECT A QUICK RETURN OF ONSHORE WINDS LATE THIS
WEEKEND AHEAD OF YET ANOTHER FRONTAL PASSAGE EXPECTED LATE MONDAY
INTO TUESDAY. 38

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      45  75  58  78  58 /   0   0  10  20  20
HOUSTON (IAH)              47  77  59  78  60 /   0  10  10  40  20
GALVESTON (GLS)            58  76  68  79  67 /   0  10  20  50  30

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 4 PM CDT THIS
     AFTERNOON FOR THE FOLLOWING ZONES: GALVESTON BAY...
     MATAGORDA BAY.

     SMALL CRAFT ADVISORY UNTIL 6 PM CDT THIS EVENING FOR THE
     FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
     CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE
     MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
     TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH ISLAND TO
     FREEPORT OUT 20 NM.

&&

$$

DISCUSSION...43
AVIATION/MARINE...31




AREA FORECAST DISCUSSION

NWS BROWNSVILLE TX

 1217 PM CDT SAT OCT 19 2013

.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.

&&

.AVIATION...DRIER AIR IS WORKING INTO THE AREA THIS AFTERNOON.
INTERMITTENT SCT TO BKN 2500 FT WILL GENERALLY BECOME MORE SCT TO
BKN AT 3500 FT THROUGH THE NEXT 3 OR 4 HOURS BEFORE BECOMING MORE
SCATTERED OVERALL. CLOUDS WILL HUG THE SIERRA MADRE KEEPING BKN TO
OVC AT AROUND 2000 FT LINGERING IN ZAPATA COUNTY...AND A BKN DECK
WILL STICK AROUND OVER THE GULF AND VERY CLOSE TO THE COAST FOR A
FEW MORE HOURS. WINDS WILL CONTINUE FROM NORTH TO NORTHEAST
GUSTING AT 20 TO 28KTS. THIS WILL GRADUALLY BEGIN DECREASING IN
THE MID TO LATE AFTERNOON BEFORE SLACKENING SIGNIFICANTLY AFTER SUNSET.

TONIGHT EXPECTING VFR CONDITIONS WITH SCT TO BKN MID CLOUD AND
FAIRLY LIGHT NORTHEAST WINDS. EXPECTING VFR CONDITIONS AT THE
START OF SUNDAY AS WELL WITH WINDS REMAINING LIGHT THROUGH THE
EARLY PART OF THE DAY. /68-JGG/

&&

.PREV DISCUSSION... /ISSUED 1108 AM CDT SAT OCT 19 2013/

DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.

AVIATION...IMPROVED THE AVIATION OUTLOOK THROUGH THE NEXT SEVERAL
HOURS WITH CIGS IMPROVING TO MVFR ACROSS MOST OF THE AREA...WITH
THE VALLEY TAF SITES CIGS BETWEEN 2300 AND 2500 FT. AREAS CLOSE TO
THE COAST...ALONG THE NORTHEASTERLY TRAJECTORY OF THE WINDS MAY KEEP
ENOUGH MOISTURE FOR A 2500 TO 3000 FT CIG THROUGH THE AFTERNOON
BUT FURTHER INLAND A LIFTING TO AROUND 3500 FT AND GRADUAL
SCATTERING OF CLOUDS IS ANTICIPATED. TAFS ADJUSTED ACCORDINGLY.
PERIODIC MVFR WILL STILL BE POSSIBLE FOR THE NEXT 3 TO 5 HOURS AT
NON TAF SITES WITH A GRADUAL IMPROVEMENT TO GENERALLY VFR
CONDITIONS WITH CIGS AROUND 3500 FT. WINDS WILL CONTINUE TO GUST
AT AROUND 25 KNOTS AND OCCASIONALLY HIGHER. /68-JGG/

PREV DISCUSSION... /ISSUED 859 AM CDT SAT OCT 19 2013/

DISCUSSION...TWEAKED POPS DOWN TO SLIGHT CHANCE ALONG THE COAST
AND RIVER WITH THE FRONT A FEW HOURS AHEAD OF SCHEDULE. OBS FROM
SOUTH PADRE ISLAND ARE MEETING WIND ADVISORY CRITERIA...AND KBRO
VWP TRENDS SHOW STRONGER 1000-2000FT LEVEL WINDS AS THE DEEPER
COLD ADVECTION MOVES IN. BASED ON OBS AND RAP GUIDANCE EXPECT AT
OR NEAR ADVISORY LEVEL CONDITIONS ON SOUTH PADRE ISLAND AND RIGHT
NEAR THE LAGUNA MADRE THROUGH THE NEXT FEW HOURS SO ISSUED A WIND
ADVISORY UNTIL 2PM. THE FREQUENT GUST TRENDS AND EXPECTATIONS DO
NOT QUITE REQUIRE A GALE WARNING FOR THE LAGUNA/NEARSHORE WATERS
AT THIS TIME. /68-JGG/

PREV DISCUSSION... /ISSUED 749 AM CDT SAT OCT 19 2013/

DISCUSSION...12Z RAOB ANALYSIS AND SURFACE OBSERVATIONS SHOW MUCH
MORE EXTENSIVE 925/850MB COLD ADVECTION THAN WHAT WAS ORIGINALLY
ANTICIPATED WITH THIS COLD FRONT. BUOY OBSERVATIONS ARE PUSHING
GALE FORCE GUSTS IN THE LAST HOUR...AND BASED ON RAP AND OBSERVED
ANALYSIS STRONGER COLD ADVECTION/WIND IS EXPECTED THROUGH THE NEXT
FEW HOURS. WITH THAT UPGRADED THE OFFSHORE WATERS TO A GALE
WARNING THROUGH 4 PM THIS AFTERNOON FOR FREQUENT GALE FORCE GUSTS.
/68-JGG/

MARINE...HAVE UPGRADED THE SMALL CRAFT ADVISORY TO A GALE WARNING
FOR FREQUENT GALE FORCE GUSTS IN THE OFFSHORE ZONES.

PREV DISCUSSION... /ISSUED 651 AM CDT SAT OCT 19 2013/

DISCUSSION...UPDATED FOR LATEST MARINE DISCUSSION BELOW.

MARINE...HAVE MOVED UP THE STARTING TIME OF THE SCA WITH WINDS
BEHIND A LINE OF THUNDERSTORMS EXCEEDING SCA CRITERIA. DO NOT
BELIEVE THERE WILL BE MUCH OF LULL BEFORE HIGH PRESSURE BUILDS
TOWARDS THE COAST IN WAKE OF A COLD FRONT NOW MOVING ACROSS THE
NORTHERN RANCHLANDS. WINDS ACROSS THE LAGUNA MADRE WILL ALSO BE ON
THE INCREASE THIS EARLIER THIS MORNING.

PREV DISCUSSION... /ISSUED 628 AM CDT SAT OCT 19 2013/

DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.

AVIATION...IFR CIGS SPREADING ACROSS THE REGION EARLY THIS
MORNING. EXPECT CIGS TO LOWER AT KHRL AND KBRO BY OR SHORTLY AFTER
SUNRISE. THE LOWER CIGS TO PERSIST THROUGH THE MORNING WITH A SLOW
RISE TO MVFR THIS AFTERNOON. VFR CONDITIONS NOT EXPECTED AT THE
REGIONAL AIRPORTS UNTIL THE EVENING HOURS. HIGH PRESSURE BUILDS
SOUTH INCREASING THE NORTH WIND. GUSTS TO 25 KNOTS ARE POSSIBLE
WITH A STEADY 12-18 KNOT WIND THROUGH THE DAY.

PREV DISCUSSION... /ISSUED 426 AM CDT SAT OCT 19 2013/

SHORT TERM /NOW THROUGH SUNDAY/...
SURFACE OBSERVATIONS INDICATE TWO FRONTS ACROSS SOUTH TEXAS THIS
MORNING. THE LEAD STATIONARY FRONT PARALLELS THE COAST WITH A WEAK
SURFACE LOW OR FRONTAL WAVE EAST OF KENEDY COUNTY. THE SECOND FRONT
EXTENDS FROM NEAR SHREVEPORT TO COTULLA.

MAIN CHALLENGE FOR TODAY IS THE POP FORECAST FOLLOWED BY THE
TEMPERATURES. MOST CONVECTION CURRENTLY HAS BEEN DEVELOPING ALONG
THE COASTAL TROUGH AND NORTHEAST OF SURFACE LOW. MOST OF SOUTH TEXAS
REMAINS UNDER LARGE SCALE ASCENT WITH THE REGION UNDER THE RIGHT
REAR QUADRANT OF 100+ KNOT JET. HOWEVER BEST SURFACE CONVERGENCE IS
NOTED ALONG THE LEAD BOUNDARY AND SURFACE LOW. ANOTHER WEAK
DISTURBANCE IS APPROACHING THE COASTAL AREAS OF TAMAULIPAS WHICH
LOOKS TO PASS TO OUR SOUTH. GUT FEELING FROM CURRENT TRENDS IS FOR
THE MAJORITY OF THE CONVECTION TO REMAIN OFFSHORE WITH SOME ISOLATED
TO POSSIBLE SCATTERED ACTIVITY DEVELOPING OVER THE COASTAL COUNTIES
BEFORE SUNRISE.  AS THE SECOND FRONT MOVES INTO THE AREA THE BEST
MOISTURE WILL BE SHOVED EAST WITH LITTLE LEFT TO PRODUCE AS MUCH
RAIN AS WHAT IS CURRENTLY PROJECTED IN THE FORECAST. HAVE ALREADY
LOWERED RAIN CHANCES BUT HAVE REDUCE THE MENTION OF THUNDER EXCEPT
OVER KENEDY COUNTY AND THE GULF WATERS. TIMING OF THE SECOND FRONT
IN LINE WITH THE NAM MODEL WHICH IS ABOUT 3 HOURS SLOWER THEN THE
GFS. THE FRONT TO MOVE THROUGH THE NORTHERN ZONES AROUND OR SHORTLY
AFTER SUNRISE WORKING ITS WAY SOUTH OF BROWNSVILLE BY 10 AM. WE CAN
EXPECT OUR WINDS TO TURN NORTH TO NORTHWEST AHEAD OF THE SECOND
FRONT WITH A MORE NOTICEABLE AIRMASS CHANGE WITH STRONGER WIND AND
COOLING TEMPERATURES AS THE SECOND BOUNDARY PASSES THROUGH THE
REGION.  CURRENT OBSERVATIONS INDICATE A NICE COOL AIRMASS OVER
NORTH CENTRAL TEXAS AND SOME OF THAT AIR TO SPREAD SOUTH AS NORTH
WINDS INCREASE TO BREEZY LEVELS. EXPECT HIGH TEMPERATURES TO OCCUR
THIS MORNING WITH A SLOW STEADY FALL THROUGH THE AFTERNOON. ANY RAIN
THAT FALLS BEHIND THE FRONT WILL PROVIDE AN EVAPORATIVE COOLING
AFFECT WHICH WILL ALLOW FOR TEMPERATURES TO FALL MORE QUICKLY ALBEIT
FOR A SHORT WHILE. IN ANY CASE HAVE LOWERED TEMPERATURES A FEW
DEGREES AND IT WILL FEEL A BIT CHILLY WITH A GRAY OVERCAST HOLDING
TOUGH ALL DAY.

TONIGHT...COOL SURFACE HIGH BUILDS MORE OVER EAST TEXAS THEN OVER
OUR REGION WITH NORTH WINDS VEERING NORTHEAST AND DIMINISHING
RAPIDLY. THE COLD AIR ADVECTION DURING THE DAYTIME HOURS WILL BE
WEAKENING.  GUIDANCE TEMPERATURES HAVE LOWERED A FEW DEGREES OVER
PREVIOUS RUNS AND WITH EVIDENCE OF TEMPERATURES UPSTREAM WILL TREND
IN THIS DIRECTION EVEN WITH AN OVERCAST CONDITIONS. DO NOT EXPECT
THE CLOUDS TO CLEAR AS 700MB FLOW TURNS SOUTHWEST DEVELOPING WEAK
OVERRUNNING.

SUNDAY...HIGH PRESSURE MOVES WELL EAST AND UPPER FLOW REMAINS
WESTERLY WHICH WILL ALLOW FOR OUR AIRMASS TO BEGIN MODIFYING RATHER
QUICKLY. FRONT STALLS WELL SOUTH AND THE EXPECTED DEVELOPMENT OF A
COASTAL TROUGH MIGHT BE DELAYED BY 6 HOURS. THIS WILL KEEP OUR RAIN
CHANCES LOWER AND LIKELY OUT OVER THE GULF. A SHORTWAVE TROUGH IN
THE WESTERLY FLOW EVENTUALLY WORKS ITS WAY NEAR THE BIG BEND AREA
WITH THE SURFACE INFLECTION DEVELOPING LATER IN THE DAY OR IN THE
EVENING WITH RAIN CHANCES POSSIBLY INCREASE AFTER DARK. WINDS TO
VEER EAST AND TEMPERATURES TO WARM UP WITH SOME BREAKS IN THE
OVERCAST ESPECIALLY ACROSS THE NORTH AND WEST.  /59/

LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
BROAD UPPER-LEVEL TROUGHINESS WILL CONTINUE TO DOMINATE MUCH OF THE
CENTRAL AND EASTERN UNITED STATES AS WE HEAD INTO THE LONG TERM
PORTION OF THE FORECAST.  CLOSER TO HOME...IT LOOKS LIKE SHOWER
POSSIBILITIES WILL CONTINUE AS WE HEAD TOWARD THE START OF THE NEW
WORKWEEK AS A COASTAL TROUGH REMAINS IN PLACE.

LOW-LEVEL THETA-E VALUES WILL LIKELY APPROACH 340K DURING THIS
PERIOD...WITH PRECIPITABLE WATER VALUES RANGING FROM 1.8 INCHES NEAR
THE US-281 CORRIDOR TO A LITTLE MORE THAN 2 INCHES ALONG THE COAST
AND OFFSHORE.  THESE PRECIPITABLE WATER VALUES ARE ABOVE THE 75TH
PERCENTILE CLIMATOLOGICALLY.  IN OTHER WORDS...PLENTY OF MOISTURE
SHOULD BE SEEN THROUGH THE BOUNDARY LAYER SUNDAY NIGHT AND MONDAY.
COMBINED WITH THE PRESENCE OF THE COASTAL TROUGH...AT LEAST A
SCATTERING OF SHOWERS WILL LIKELY BE SEEN.

I HAVE A CONCERN OR TWO ABOUT THIS SCENARIO THOUGH.  MOST OF THE
ISENTROPIC ASCENT AND LOWER CONDENSATION PRESSURE DEFICITS /ALONG
THE 310K THETA SURFACE/ SHIFT OFFSHORE SUNDAY EVENING...WITH
ADDITIONAL MOISTURE MOVING INTO THIS REGION OVERNIGHT.  THE UPGLIDE
THEN STRENGTHENS AND STARTS TO MOVE NORTHEAST /AND AWAY FROM OUR
AREA/ MONDAY MORNING.  EVIDENCE OF THIS ALSO EXISTS IN THE QG
FIELDS...AS A MID-LEVEL SHORTWAVE TROUGH MOVES NORTHEAST THROUGH THE
REGION.

THIS IMPLIES TO ME TWO THINGS.  FIRST...THE BEST TIME TO SEE
PRECIPITATION FOR OUR REGION WILL LIKELY BE LATE SUNDAY NIGHT...
WITH DIMINISHING ODDS MONDAY MORNING.  THIS IS A TAD FASTER THAN
WHAT THE CURRENT FORECAST IMPLIES.  SECOND...THE ODDS OF SEEING
SHOWERS /MAINLY OVER LAND AREAS/ MAY NOT BE AS GREAT AS THE CURRENT
FORECAST.  WITH THIS FORECAST PACKAGE...I HAVE MADE SOME TWEAKS TO
TIMING BASED ON THE LATEST DATA.  PRECIPITATION PROBABILITIES HAVE
LARGELY REMAINED UNTOUCHED...AND WILL ALLOW SUBSEQUENT SHIFTS TO
FINE TUNE THE FORECAST USING THE LATEST AVAILABLE DATA.

CONDITIONS SHOULD START TO DRY OUT A BIT MONDAY AFTERNOON AND
EVENING...AS THE SURFACE TROUGH MOVES FARTHER OFFSHORE.  A SHORTWAVE
TROUGH IS EXPECTED TO SWING THROUGH THE SOUTHERN PLAINS MONDAY NIGHT
INTO TUESDAY MORNING.  THERE MAY BE ENOUGH MOMENTUM ASSOCIATED WITH
THIS FEATURE TO PUSH A WEAK COLD FRONT THROUGH THE AREA TUESDAY
MORNING.  SOME LOW CLOUDS MAY REMAIN IN PLACE BEHIND THE FRONT
THANKS TO A BIT OF LINGERING THERMAL TROUGHINESS AT 850MB.

THE UPPER TROUGH AXIS IS FORECAST TO SHIFT EAST WEDNESDAY.
NORTHWEST FLOW ALOFT OVER OUR AREA IN WAKE OF THIS SYSTEM SHOULD
ALLOW THE CENTER OF A SURFACE HIGH TO HEAD INTO THE OZARKS
WEDNESDAY.  WEAK SHORTWAVE RIDGING...COMBINED WITH A SURFACE HIGH
NEAR THE ARKLAMISS SHOULD ALLOW QUIET WEATHER CONDITIONS TO BE SEEN
FOR THE REMAINDER OF THE UPCOMING WORKWEEK.  /BUTTS/

MARINE...

TODAY THROUGH SUNDAY...
SMALL CRAFT ADVISORIES ARE IN PLACE FOR ALL COASTAL WATERS TODAY AS
NORTH WINDS TO INCREASE BEHIND A COLD FRONT POISED TO MOVE OFFSHORE
AFTER SUNRISE. SEAS TO RESPOND RATHER QUICKLY WITH ROUGH CONDITIONS
BY OR BEFORE NOON. HIGH PRESSURE TO BUILDS NORTH AND EAST OF THE
LOWER TEXAS COAST TONIGHT INTO SUNDAY WITH WINDS AND SEAS LOWERING.
SCA COULD PERSIST FOR THE OFFSHORE WATERS THIS EVENING BUT SHOULD
FALL BELOW CRITERIA BY MIDNIGHT. MORNING SHOWERS AND THUNDERSTORMS
TO FAVOR THE NORTHERN WATERS WITH AREAS OF RAIN WITH EMBEDDED
SHOWERS ACROSS THE SOUTH. MOST OF THE STORMS TO PUSH OFF TO THE
NORTHEAST BEFORE NOON.  /59/

SUNDAY NIGHT THROUGH WEDNESDAY...
A TROUGH OF LOW PRESSURE JUST OFFSHORE...COMBINED WITH AMPLE
MOISTURE...SHOULD ALLOW SHOWERS AND A FEW STORMS TO BE SEEN OVER THE
MARINE AREA SUNDAY NIGHT THROUGH MONDAY.  E WINDS /GENERALLY 10 KTS
OR LESS/ SHOULD BECOME SE SUNDAY NIGHT...THEN BECOME SW-W MONDAY
AFTERNOON AS THE TROUGH MOVES FARTHER OFFSHORE.  A WEAK COLD FRONT
IS FORECAST TO MOVE THROUGH THE MARINE AREA TUESDAY.  THIS IS
EXPECTED TO RESULT IN STRENGTHENING N-NE WINDS AND BUILDING SEAS.
SMALL CRAFT ADVISORIES MAY BE NEEDED FOR ALL OR PART OF THE MARINE
AREA DURING THIS TIME.  /BUTTS/

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...WIND ADVISORY UNTIL 2 PM CDT THIS AFTERNOON FOR TXZ256-257.

GM...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR GMZ130-132-
     135.

     SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 1 AM CDT SUNDAY
     FOR GMZ170-175.

     GALE WARNING UNTIL 4 PM CDT THIS AFTERNOON FOR GMZ170-175.

     SMALL CRAFT ADVISORY UNTIL 1 AM CDT SUNDAY FOR GMZ150-155.

&&

$$

THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV

68/61






AREA FORECAST DISCUSSION...UPDATED

NWS BROWNSVILLE TX

 1108 AM CDT SAT OCT 19 2013

.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.

&&

.AVIATION...IMPROVED THE AVIATION OUTLOOK THROUGH THE NEXT SEVERAL
HOURS WITH CIGS IMPROVING TO MVFR ACROSS MOST OF THE AREA...WITH
THE VALLEY TAF SITES CIGS BETWEEN 2300 AND 2500 FT. AREAS CLOSE TO
THE COAST...ALONG THE NORTHEASTERLY TRAJECTORY OF THE WINDS MAY KEEP
ENOUGH MOISTURE FOR A 2500 TO 3000 FT CIG THROUGH THE AFTERNOON
BUT FURTHER INLAND A LIFTING TO AROUND 3500 FT AND GRADUAL
SCATTERING OF CLOUDS IS ANTICIPATED. TAFS ADJUSTED ACCORDINGLY.
PERIODIC MVFR WILL STILL BE POSSIBLE FOR THE NEXT 3 TO 5 HOURS AT
NON TAF SITES WITH A GRADUAL IMPROVEMENT TO GENERALLY VFR
CONDITIONS WITH CIGS AROUND 3500 FT. WINDS WILL CONTINUE TO GUST
AT AROUND 25 KNOTS AND OCCASIONALLY HIGHER. /68-JGG/

&&

.PREV DISCUSSION... /ISSUED 859 AM CDT SAT OCT 19 2013/

DISCUSSION...TWEAKED POPS DOWN TO SLIGHT CHANCE ALONG THE COAST
AND RIVER WITH THE FRONT A FEW HOURS AHEAD OF SCHEDULE. OBS FROM
SOUTH PADRE ISLAND ARE MEETING WIND ADVISORY CRITERIA...AND KBRO
VWP TRENDS SHOW STRONGER 1000-2000FT LEVEL WINDS AS THE DEEPER
COLD ADVECTION MOVES IN. BASED ON OBS AND RAP GUIDANCE EXPECT AT
OR NEAR ADVISORY LEVEL CONDITIONS ON SOUTH PADRE ISLAND AND RIGHT
NEAR THE LAGUNA MADRE THROUGH THE NEXT FEW HOURS SO ISSUED A WIND
ADVISORY UNTIL 2PM. THE FREQUENT GUST TRENDS AND EXPECTATIONS DO
NOT QUITE REQUIRE A GALE WARNING FOR THE LAGUNA/NEARSHORE WATERS
AT THIS TIME. /68-JGG/

PREV DISCUSSION... /ISSUED 749 AM CDT SAT OCT 19 2013/

DISCUSSION...12Z RAOB ANALYSIS AND SURFACE OBSERVATIONS SHOW MUCH
MORE EXTENSIVE 925/850MB COLD ADVECTION THAN WHAT WAS ORIGINALLY
ANTICIPATED WITH THIS COLD FRONT. BUOY OBSERVATIONS ARE PUSHING
GALE FORCE GUSTS IN THE LAST HOUR...AND BASED ON RAP AND OBSERVED
ANALYSIS STRONGER COLD ADVECTION/WIND IS EXPECTED THROUGH THE NEXT
FEW HOURS. WITH THAT UPGRADED THE OFFSHORE WATERS TO A GALE
WARNING THROUGH 4 PM THIS AFTERNOON FOR FREQUENT GALE FORCE GUSTS.
/68-JGG/

MARINE...HAVE UPGRADED THE SMALL CRAFT ADVISORY TO A GALE WARNING
FOR FREQUENT GALE FORCE GUSTS IN THE OFFSHORE ZONES.

PREV DISCUSSION... /ISSUED 651 AM CDT SAT OCT 19 2013/

DISCUSSION...UPDATED FOR LATEST MARINE DISCUSSION BELOW.

MARINE...HAVE MOVED UP THE STARTING TIME OF THE SCA WITH WINDS
BEHIND A LINE OF THUNDERSTORMS EXCEEDING SCA CRITERIA. DO NOT
BELIEVE THERE WILL BE MUCH OF LULL BEFORE HIGH PRESSURE BUILDS
TOWARDS THE COAST IN WAKE OF A COLD FRONT NOW MOVING ACROSS THE
NORTHERN RANCHLANDS. WINDS ACROSS THE LAGUNA MADRE WILL ALSO BE ON
THE INCREASE THIS EARLIER THIS MORNING.

PREV DISCUSSION... /ISSUED 628 AM CDT SAT OCT 19 2013/

DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.

AVIATION...IFR CIGS SPREADING ACROSS THE REGION EARLY THIS
MORNING. EXPECT CIGS TO LOWER AT KHRL AND KBRO BY OR SHORTLY AFTER
SUNRISE. THE LOWER CIGS TO PERSIST THROUGH THE MORNING WITH A SLOW
RISE TO MVFR THIS AFTERNOON. VFR CONDITIONS NOT EXPECTED AT THE
REGIONAL AIRPORTS UNTIL THE EVENING HOURS. HIGH PRESSURE BUILDS
SOUTH INCREASING THE NORTH WIND. GUSTS TO 25 KNOTS ARE POSSIBLE
WITH A STEADY 12-18 KNOT WIND THROUGH THE DAY.

PREV DISCUSSION... /ISSUED 426 AM CDT SAT OCT 19 2013/

SHORT TERM /NOW THROUGH SUNDAY/...
SURFACE OBSERVATIONS INDICATE TWO FRONTS ACROSS SOUTH TEXAS THIS
MORNING. THE LEAD STATIONARY FRONT PARALLELS THE COAST WITH A WEAK
SURFACE LOW OR FRONTAL WAVE EAST OF KENEDY COUNTY. THE SECOND FRONT
EXTENDS FROM NEAR SHREVEPORT TO COTULLA.

MAIN CHALLENGE FOR TODAY IS THE POP FORECAST FOLLOWED BY THE
TEMPERATURES. MOST CONVECTION CURRENTLY HAS BEEN DEVELOPING ALONG
THE COASTAL TROUGH AND NORTHEAST OF SURFACE LOW. MOST OF SOUTH TEXAS
REMAINS UNDER LARGE SCALE ASCENT WITH THE REGION UNDER THE RIGHT
REAR QUADRANT OF 100+ KNOT JET. HOWEVER BEST SURFACE CONVERGENCE IS
NOTED ALONG THE LEAD BOUNDARY AND SURFACE LOW. ANOTHER WEAK
DISTURBANCE IS APPROACHING THE COASTAL AREAS OF TAMAULIPAS WHICH
LOOKS TO PASS TO OUR SOUTH. GUT FEELING FROM CURRENT TRENDS IS FOR
THE MAJORITY OF THE CONVECTION TO REMAIN OFFSHORE WITH SOME ISOLATED
TO POSSIBLE SCATTERED ACTIVITY DEVELOPING OVER THE COASTAL COUNTIES
BEFORE SUNRISE.  AS THE SECOND FRONT MOVES INTO THE AREA THE BEST
MOISTURE WILL BE SHOVED EAST WITH LITTLE LEFT TO PRODUCE AS MUCH
RAIN AS WHAT IS CURRENTLY PROJECTED IN THE FORECAST. HAVE ALREADY
LOWERED RAIN CHANCES BUT HAVE REDUCE THE MENTION OF THUNDER EXCEPT
OVER KENEDY COUNTY AND THE GULF WATERS. TIMING OF THE SECOND FRONT
IN LINE WITH THE NAM MODEL WHICH IS ABOUT 3 HOURS SLOWER THEN THE
GFS. THE FRONT TO MOVE THROUGH THE NORTHERN ZONES AROUND OR SHORTLY
AFTER SUNRISE WORKING ITS WAY SOUTH OF BROWNSVILLE BY 10 AM. WE CAN
EXPECT OUR WINDS TO TURN NORTH TO NORTHWEST AHEAD OF THE SECOND
FRONT WITH A MORE NOTICEABLE AIRMASS CHANGE WITH STRONGER WIND AND
COOLING TEMPERATURES AS THE SECOND BOUNDARY PASSES THROUGH THE
REGION.  CURRENT OBSERVATIONS INDICATE A NICE COOL AIRMASS OVER
NORTH CENTRAL TEXAS AND SOME OF THAT AIR TO SPREAD SOUTH AS NORTH
WINDS INCREASE TO BREEZY LEVELS. EXPECT HIGH TEMPERATURES TO OCCUR
THIS MORNING WITH A SLOW STEADY FALL THROUGH THE AFTERNOON. ANY RAIN
THAT FALLS BEHIND THE FRONT WILL PROVIDE AN EVAPORATIVE COOLING
AFFECT WHICH WILL ALLOW FOR TEMPERATURES TO FALL MORE QUICKLY ALBEIT
FOR A SHORT WHILE. IN ANY CASE HAVE LOWERED TEMPERATURES A FEW
DEGREES AND IT WILL FEEL A BIT CHILLY WITH A GRAY OVERCAST HOLDING
TOUGH ALL DAY.

TONIGHT...COOL SURFACE HIGH BUILDS MORE OVER EAST TEXAS THEN OVER
OUR REGION WITH NORTH WINDS VEERING NORTHEAST AND DIMINISHING
RAPIDLY. THE COLD AIR ADVECTION DURING THE DAYTIME HOURS WILL BE
WEAKENING.  GUIDANCE TEMPERATURES HAVE LOWERED A FEW DEGREES OVER
PREVIOUS RUNS AND WITH EVIDENCE OF TEMPERATURES UPSTREAM WILL TREND
IN THIS DIRECTION EVEN WITH AN OVERCAST CONDITIONS. DO NOT EXPECT
THE CLOUDS TO CLEAR AS 700MB FLOW TURNS SOUTHWEST DEVELOPING WEAK
OVERRUNNING.

SUNDAY...HIGH PRESSURE MOVES WELL EAST AND UPPER FLOW REMAINS
WESTERLY WHICH WILL ALLOW FOR OUR AIRMASS TO BEGIN MODIFYING RATHER
QUICKLY. FRONT STALLS WELL SOUTH AND THE EXPECTED DEVELOPMENT OF A
COASTAL TROUGH MIGHT BE DELAYED BY 6 HOURS. THIS WILL KEEP OUR RAIN
CHANCES LOWER AND LIKELY OUT OVER THE GULF. A SHORTWAVE TROUGH IN
THE WESTERLY FLOW EVENTUALLY WORKS ITS WAY NEAR THE BIG BEND AREA
WITH THE SURFACE INFLECTION DEVELOPING LATER IN THE DAY OR IN THE
EVENING WITH RAIN CHANCES POSSIBLY INCREASE AFTER DARK. WINDS TO
VEER EAST AND TEMPERATURES TO WARM UP WITH SOME BREAKS IN THE
OVERCAST ESPECIALLY ACROSS THE NORTH AND WEST.  /59/

LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
BROAD UPPER-LEVEL TROUGHINESS WILL CONTINUE TO DOMINATE MUCH OF THE
CENTRAL AND EASTERN UNITED STATES AS WE HEAD INTO THE LONG TERM
PORTION OF THE FORECAST.  CLOSER TO HOME...IT LOOKS LIKE SHOWER
POSSIBILITIES WILL CONTINUE AS WE HEAD TOWARD THE START OF THE NEW
WORKWEEK AS A COASTAL TROUGH REMAINS IN PLACE.

LOW-LEVEL THETA-E VALUES WILL LIKELY APPROACH 340K DURING THIS
PERIOD...WITH PRECIPITABLE WATER VALUES RANGING FROM 1.8 INCHES NEAR
THE US-281 CORRIDOR TO A LITTLE MORE THAN 2 INCHES ALONG THE COAST
AND OFFSHORE.  THESE PRECIPITABLE WATER VALUES ARE ABOVE THE 75TH
PERCENTILE CLIMATOLOGICALLY.  IN OTHER WORDS...PLENTY OF MOISTURE
SHOULD BE SEEN THROUGH THE BOUNDARY LAYER SUNDAY NIGHT AND MONDAY.
COMBINED WITH THE PRESENCE OF THE COASTAL TROUGH...AT LEAST A
SCATTERING OF SHOWERS WILL LIKELY BE SEEN.

I HAVE A CONCERN OR TWO ABOUT THIS SCENARIO THOUGH.  MOST OF THE
ISENTROPIC ASCENT AND LOWER CONDENSATION PRESSURE DEFICITS /ALONG
THE 310K THETA SURFACE/ SHIFT OFFSHORE SUNDAY EVENING...WITH
ADDITIONAL MOISTURE MOVING INTO THIS REGION OVERNIGHT.  THE UPGLIDE
THEN STRENGTHENS AND STARTS TO MOVE NORTHEAST /AND AWAY FROM OUR
AREA/ MONDAY MORNING.  EVIDENCE OF THIS ALSO EXISTS IN THE QG
FIELDS...AS A MID-LEVEL SHORTWAVE TROUGH MOVES NORTHEAST THROUGH THE
REGION.

THIS IMPLIES TO ME TWO THINGS.  FIRST...THE BEST TIME TO SEE
PRECIPITATION FOR OUR REGION WILL LIKELY BE LATE SUNDAY NIGHT...
WITH DIMINISHING ODDS MONDAY MORNING.  THIS IS A TAD FASTER THAN
WHAT THE CURRENT FORECAST IMPLIES.  SECOND...THE ODDS OF SEEING
SHOWERS /MAINLY OVER LAND AREAS/ MAY NOT BE AS GREAT AS THE CURRENT
FORECAST.  WITH THIS FORECAST PACKAGE...I HAVE MADE SOME TWEAKS TO
TIMING BASED ON THE LATEST DATA.  PRECIPITATION PROBABILITIES HAVE
LARGELY REMAINED UNTOUCHED...AND WILL ALLOW SUBSEQUENT SHIFTS TO
FINE TUNE THE FORECAST USING THE LATEST AVAILABLE DATA.

CONDITIONS SHOULD START TO DRY OUT A BIT MONDAY AFTERNOON AND
EVENING...AS THE SURFACE TROUGH MOVES FARTHER OFFSHORE.  A SHORTWAVE
TROUGH IS EXPECTED TO SWING THROUGH THE SOUTHERN PLAINS MONDAY NIGHT
INTO TUESDAY MORNING.  THERE MAY BE ENOUGH MOMENTUM ASSOCIATED WITH
THIS FEATURE TO PUSH A WEAK COLD FRONT THROUGH THE AREA TUESDAY
MORNING.  SOME LOW CLOUDS MAY REMAIN IN PLACE BEHIND THE FRONT
THANKS TO A BIT OF LINGERING THERMAL TROUGHINESS AT 850MB.

THE UPPER TROUGH AXIS IS FORECAST TO SHIFT EAST WEDNESDAY.
NORTHWEST FLOW ALOFT OVER OUR AREA IN WAKE OF THIS SYSTEM SHOULD
ALLOW THE CENTER OF A SURFACE HIGH TO HEAD INTO THE OZARKS
WEDNESDAY.  WEAK SHORTWAVE RIDGING...COMBINED WITH A SURFACE HIGH
NEAR THE ARKLAMISS SHOULD ALLOW QUIET WEATHER CONDITIONS TO BE SEEN
FOR THE REMAINDER OF THE UPCOMING WORKWEEK.  /BUTTS/

MARINE...

TODAY THROUGH SUNDAY...
SMALL CRAFT ADVISORIES ARE IN PLACE FOR ALL COASTAL WATERS TODAY AS
NORTH WINDS TO INCREASE BEHIND A COLD FRONT POISED TO MOVE OFFSHORE
AFTER SUNRISE. SEAS TO RESPOND RATHER QUICKLY WITH ROUGH CONDITIONS
BY OR BEFORE NOON. HIGH PRESSURE TO BUILDS NORTH AND EAST OF THE
LOWER TEXAS COAST TONIGHT INTO SUNDAY WITH WINDS AND SEAS LOWERING.
SCA COULD PERSIST FOR THE OFFSHORE WATERS THIS EVENING BUT SHOULD
FALL BELOW CRITERIA BY MIDNIGHT. MORNING SHOWERS AND THUNDERSTORMS
TO FAVOR THE NORTHERN WATERS WITH AREAS OF RAIN WITH EMBEDDED
SHOWERS ACROSS THE SOUTH. MOST OF THE STORMS TO PUSH OFF TO THE
NORTHEAST BEFORE NOON.  /59/

SUNDAY NIGHT THROUGH WEDNESDAY...
A TROUGH OF LOW PRESSURE JUST OFFSHORE...COMBINED WITH AMPLE
MOISTURE...SHOULD ALLOW SHOWERS AND A FEW STORMS TO BE SEEN OVER THE
MARINE AREA SUNDAY NIGHT THROUGH MONDAY.  E WINDS /GENERALLY 10 KTS
OR LESS/ SHOULD BECOME SE SUNDAY NIGHT...THEN BECOME SW-W MONDAY
AFTERNOON AS THE TROUGH MOVES FARTHER OFFSHORE.  A WEAK COLD FRONT
IS FORECAST TO MOVE THROUGH THE MARINE AREA TUESDAY.  THIS IS
EXPECTED TO RESULT IN STRENGTHENING N-NE WINDS AND BUILDING SEAS.
SMALL CRAFT ADVISORIES MAY BE NEEDED FOR ALL OR PART OF THE MARINE
AREA DURING THIS TIME.  /BUTTS/

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...WIND ADVISORY UNTIL 2 PM CDT THIS AFTERNOON FOR TXZ256-257.

GM...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR GMZ130-132-
     135.

     SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 1 AM CDT SUNDAY
     FOR GMZ170-175.

     GALE WARNING UNTIL 4 PM CDT THIS AFTERNOON FOR GMZ170-175.

     SMALL CRAFT ADVISORY UNTIL 1 AM CDT SUNDAY FOR GMZ150-155.

&&

$$

THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV

68/61






AREA FORECAST DISCUSSION

NWS HOUSTON/GALVESTON TX

 1039 AM CDT SAT OCT 19 2013

.UPDATE...
SEE MORNING UPDATE.

&&

.DISCUSSION...
A COLD FRONT HAS CLEARED THE COAST AND SIGNIFICANTLY COOLER
TEMPERATURES AND DRIER AIR ARE FILTERING INTO SOUTHEAST TEXAS.
GRADIENT REMAINS RATHER TIGHT AND SO AM EXPECTING BREEZY CONDS TO
PERSIST. BETWEEN COLD AIR ADVECTION AND MIXING...AM NOT SURE THAT
THEY`LL BE MUCH OF A WARM UP TODAY DESPITE FULL SUNSHINE EXPECTED
THIS AFTN. TWEAKED MAX TEMPS A BIT LOWER OVER THE NORTH. TWEAKED
SKY GRIDS A BIT TO REFLECT RAPID CLEARING OVER THE NORTHERN ZONES.
THE CHANGES ARE VERY MINOR AND THE INTEGRITY OF THE PREVIOUS FCST
IS UNCHANGED AND ON TRACK. 43


&&

.PREV DISCUSSION... /ISSUED 631 AM CDT SAT OCT 19 2013/

UPDATE...
EARLY MORNING UPDATE FOR RAIN MOVING OUT OF THE AREA.

DISCUSSION...
KEEPING UP WITH LATEST RADAR TRENDS HAVE UPDATED RAIN CHANCES FOR
THE DAY AS PRECIP CONTINUES TO MOVE EAST OUT INTO THE GULF. LOOKS
LIKE MOSTLY CLOUDY SKIES TO START THIS MORNING AS COLD FRONT
PUSHES THROUGH THE AREA. COLD FRONT CURRENTLY PUSHING THROUGH
CONROE AND APPROACHING THE HOUSTON AREA. FRONT SHOULD PUSH OFF THE
COAST MID MORNING. UPDATED FORECAST PRODUCTS HAVE BEEN ISSUED.

39

PREV DISCUSSION... /ISSUED 608 AM CDT SAT OCT 19 2013/

DISCUSSION...
SEE AVIATION FOR 12Z TAF DISCUSSION

AVIATION...
SHRA HAVE MOVED OFFSHORE THIS MORNING AND ALL PRECIP MENTIONS WILL
BE REMOVED FROM THE TAFS. NORTHERLY WINDS ALREADY ONGOING AT ALL
SITES AS PREFRONTAL TROUGH HAS PUSHED OFFSHORE WITH THE ACTUAL
COLD FRONT HAVING REACHED CLL AND UTS THIS MORNING. EXPECT AN HOUR
OR TWO WITH GUSTS NEAR 20KTS AS THE FRONTAL BOUNDARY PUSHES
THROUGH THIS MORNING. MAIN CONCERN WILL BE SOUTHERLY EXTENT OF
IFR/MVFR CIGS IMMEDIATELY BEHIND THE FRONT. AS THE SUN COMES UP
THIS MORNING FEEL THAT THIS LAYER WILL BEGIN TO SCATTER OUT SO
HAVE NOT INCLUDED CIGS FOR IAH ALTHOUGH A BRIEF PERIOD OF
BKN010-BKN015 IS POSSIBLE THIS MORNING BEFORE CONDITIONS IMPROVE
TO VFR BY AFTERNOON. SURFACE HIGH PRESSURE WILL SPREAD INTO
SOUTHEAST TEXAS SATURDAY EVENING LEADING TO VARIABLE WINDS ACROSS
THE INLAND AREAS OVERNIGHT INTO SUNDAY. 38

PREV DISCUSSION... /ISSUED 428 AM CDT SAT OCT 19 2013/

DISCUSSION...
COLD FRONT PUSHING SOUTH THROUGH TEXAS AT 09Z (4AM CDT) ABOUT AT
A KLFK/KUTS/K11R LINE OR BASICALLY A BRENHAM TO LUFKIN LINE. LINE
OF SHOWERS AND THUNDERSTORMS OVER HOUSTON EARLIER TONIGHT HAS
WEAKENED AND ACTIVITY HAS INCREASED MORE OFF THE UPPER TX COAST.
UPPER LEVEL SHORT WAVE LOOKS TO BE MOVING OUT OF THE AREA AND
POSSIBLE THAT UPPER LEVEL DIVERGENCE IS WEAKENING AS A RESULT.
BULK OF EARLIER CONVECTION HAS BEEN SUPPORTED BY SOME ISENTROPIC
LIFT AND FRONTOGENESIS IN 925-850MB LAYER PER SPC MESOANALYSES.
PER LATEST RADAR TRENDS...EXPECT SOME LINGERING SHOWERS ALONG THE
COAST BUT LOOKS LIKE MOST OF THE RAINFALL MAY BE DONE BY 12Z WHICH
IS A GOOD 3-6 HRS SOONER THAN MOST 00Z MODEL SOLUTIONS. HOWEVER
THE 00Z TX TECH 3KM WRF AND LATEST 06Z HRRR ARE IN GOOD AGREEMENT
WITH LATEST TRENDS. FORECAST HAS BE TRENDED TOWARDS THESE MODELS
IN THE SHORT TERM BUT MAY HOLD ONTO PRECIP A LITTLE LONGER. COLD
FRONT SHOULD BE OFF THE COAST BETWEEN 12-15Z THIS MORNING WITH
STRONG NORTHERLY WINDS ARE WIDE. UPPER LEVEL TROUGH AXIS WILL ALSO
HAVE PUSHED BY SE TX WITH RIGHT REAR QUADRANT OF JET STREAK STILL
LINGERING OVER THE AREA. HIGH PRESSURE AT THE SURFACE SHOULD
CONTINUE TO BUILD OVER TX TODAY. MAX TEMPS WILL BE A CHALLENGE AS
DO EXPECT SOME COLD ADVECTION TO OCCUR. HOWEVER 850MB TEMPS ONLY
DROP TO ABOUT 12-13C SO COULD STILL SEE TEMPS REACHING UPPER 60S
TO LOW 70S WITH DAYTIME HEATING. CLOUD COVER SHOULD CLEAR OUT SO
MAY NOT GET QUITE AS COOL AS IT COULD WITH BULK OF COLDER AIRMASS
MOVING EAST OF THE AREA OVER MISS RIVER VALLEY.

LOOKS LIKE RETURN FLOW AND WARM ADVECTION WILL ENSUE ONCE AGAIN
SUN NIGHT INTO MONDAY. VERY SIMILAR SET UP TO THE MOST RECENT RAIN
EVENT WITH WEAK ISENTROPIC LIFT AND A SHORT WAVE TROUGH ROTATING
THROUGH THE S PLAINS PROVIDING ENOUGH LARGE SCALE ASCENT FOR
ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. THINK ORIENTATION OF
JET STREAK AND SHORT WAVE TROUGH MAY PUSH BULK OF PRECIP EAST OF
SE TX SO HAVE NOT CHANGED POPS MUCH. BEST CHANCES WILL AGAIN BE
ALONG THE COAST BUT WILL KEEP AROUND 50 PERCENT FOR NOW. ANOTHER
COLD FRONT WILL ALSO PUSH INTO SE TX BUT MORE SO MON NIGHT INTO
TUE MORNING. BEST LIFT WILL HAVE SHIFTED EAST BY THIS TIME SO WILL
BE HAVING DECREASING RAIN CHANCES MON NIGHT INTO TUE.

TUE THROUGH THE REST OF THE WEEK SHOULD BE DRY WITH A RATHER
AMPLIFIED UPPER LEVEL PATTERN. BROAD RIDGE SHOULD REMAIN OVER THE
PACIFIC COAST WITH A DEEP LOW AND LONG WAVE TROUGH OVER THE GREAT
LAKES AND MIDWEST. SEVERAL SHORT WAVE TROUGHS MOVING THROUGH THE
FLOW SHOULD KEEP THE TROUGH OVER THE GREAT LAKES THROUGH THE END
OF THE WEEK. WILL GET SFC HIGH PRESSURE BUILDING OVER TX THROUGH
WED WITH ANOTHER RIDGE BUILDING OVER THE MIDWEST THUR INTO FRI.
PATTERN SHOULD KEEP CONDITIONS DRY AND ON THE COOL SIDE. TRIED TO
BLEND THE TEMP FORECAST BETWEEN GFS AND ENSEMBLE MEAN TEMPS FOR
THE LATER HALF OF THE WEEK. THIS WILL MEAN TEMPS WILL BE NEAR OR
EVEN A DEGREE OR TWO BELOW NORMAL FOR THE END OF NEXT WEEK.

39

MARINE...
NORTHERLY WINDS HAVE REACHED THE NEARSHORE BUOY THIS MORNING AS A
PREFRONTAL TROUGH PUSHES OUT AHEAD OF THE COLD FRONT MOVING INTO
SOUTHEAST TEXAS. EXPECT OFFSHORE WINDS TO PICK UP THROUGH THE
MORNING WITH BUILDING SEAS AS THE FRONT MOVES OFFSHORE. ADVISORY
FLAGS IN PLACE ACROSS ALL COASTAL WATERS TODAY AND MAY NEED TO BE
EXTENDED FURTHER STILL...ALTHOUGH WILL ALLOW NEXT SHIFT TO
EVALUATE NEW MODEL DATA AND OBSERVATIONS FROM TODAY BEFORE MAKING
THAT DECISION. EXPECT A QUICK RETURN OF ONSHORE WINDS LATE THIS
WEEKEND AHEAD OF YET ANOTHER FRONTAL PASSAGE EXPECTED LATE MONDAY
INTO TUESDAY. 38

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      66  45  75  58  78 /  10   0   0  10  20
HOUSTON (IAH)              69  47  77  59  78 /  10   0  10  10  40
GALVESTON (GLS)            72  58  76  68  79 /  10   0  10  20  50

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 4 PM CDT THIS
     AFTERNOON FOR THE FOLLOWING ZONES: GALVESTON BAY...
     MATAGORDA BAY.

     SMALL CRAFT ADVISORY UNTIL 6 PM CDT THIS EVENING FOR THE
     FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
     CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE
     MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
     TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH ISLAND TO
     FREEPORT OUT 20 NM.

&&

$$

DISCUSSION...43




AREA FORECAST DISCUSSION...UPDATED

NWS BROWNSVILLE TX

 859 AM CDT SAT OCT 19 2013

.DISCUSSION...TWEAKED POPS DOWN TO SLIGHT CHANCE ALONG THE COAST
AND RIVER WITH THE FRONT A FEW HOURS AHEAD OF SCHEDULE. OBS FROM
SOUTH PADRE ISLAND ARE MEETING WIND ADVISORY CRITERIA...AND KBRO
VWP TRENDS SHOW STRONGER 1000-2000FT LEVEL WINDS AS THE DEEPER
COLD ADVECTION MOVES IN. BASED ON OBS AND RAP GUIDANCE EXPECT AT
OR NEAR ADVISORY LEVEL CONDITIONS ON SOUTH PADRE ISLAND AND RIGHT
NEAR THE LAGUNA MADRE THROUGH THE NEXT FEW HOURS SO ISSUED A WIND
ADVISORY UNTIL 2PM. THE FREQUENT GUST TRENDS AND EXPECTATIONS DO
NOT QUITE REQUIRE A GALE WARNING FOR THE LAGUNA/NEARSHORE WATERS
AT THIS TIME. /68-JGG/

&&

.PREV DISCUSSION... /ISSUED 749 AM CDT SAT OCT 19 2013/

DISCUSSION...12Z RAOB ANALYSIS AND SURFACE OBSERVATIONS SHOW MUCH
MORE EXTENSIVE 925/850MB COLD ADVECTION THAN WHAT WAS ORIGINALLY
ANTICIPATED WITH THIS COLD FRONT. BUOY OBSERVATIONS ARE PUSHING
GALE FORCE GUSTS IN THE LAST HOUR...AND BASED ON RAP AND OBSERVED
ANALYSIS STRONGER COLD ADVECTION/WIND IS EXPECTED THROUGH THE NEXT
FEW HOURS. WITH THAT UPGRADED THE OFFSHORE WATERS TO A GALE
WARNING THROUGH 4 PM THIS AFTERNOON FOR FREQUENT GALE FORCE GUSTS.
/68-JGG/

MARINE...HAVE UPGRADED THE SMALL CRAFT ADVISORY TO A GALE WARNING
FOR FREQUENT GALE FORCE GUSTS IN THE OFFSHORE ZONES.

PREV DISCUSSION... /ISSUED 651 AM CDT SAT OCT 19 2013/

DISCUSSION...UPDATED FOR LATEST MARINE DISCUSSION BELOW.

MARINE...HAVE MOVED UP THE STARTING TIME OF THE SCA WITH WINDS
BEHIND A LINE OF THUNDERSTORMS EXCEEDING SCA CRITERIA. DO NOT
BELIEVE THERE WILL BE MUCH OF LULL BEFORE HIGH PRESSURE BUILDS
TOWARDS THE COAST IN WAKE OF A COLD FRONT NOW MOVING ACROSS THE
NORTHERN RANCHLANDS. WINDS ACROSS THE LAGUNA MADRE WILL ALSO BE ON
THE INCREASE THIS EARLIER THIS MORNING.

PREV DISCUSSION... /ISSUED 628 AM CDT SAT OCT 19 2013/

DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.

AVIATION...IFR CIGS SPREADING ACROSS THE REGION EARLY THIS
MORNING. EXPECT CIGS TO LOWER AT KHRL AND KBRO BY OR SHORTLY AFTER
SUNRISE. THE LOWER CIGS TO PERSIST THROUGH THE MORNING WITH A SLOW
RISE TO MVFR THIS AFTERNOON. VFR CONDITIONS NOT EXPECTED AT THE
REGIONAL AIRPORTS UNTIL THE EVENING HOURS. HIGH PRESSURE BUILDS
SOUTH INCREASING THE NORTH WIND. GUSTS TO 25 KNOTS ARE POSSIBLE
WITH A STEADY 12-18 KNOT WIND THROUGH THE DAY.

PREV DISCUSSION... /ISSUED 426 AM CDT SAT OCT 19 2013/

SHORT TERM /NOW THROUGH SUNDAY/...
SURFACE OBSERVATIONS INDICATE TWO FRONTS ACROSS SOUTH TEXAS THIS
MORNING. THE LEAD STATIONARY FRONT PARALLELS THE COAST WITH A WEAK
SURFACE LOW OR FRONTAL WAVE EAST OF KENEDY COUNTY. THE SECOND FRONT
EXTENDS FROM NEAR SHREVEPORT TO COTULLA.

MAIN CHALLENGE FOR TODAY IS THE POP FORECAST FOLLOWED BY THE
TEMPERATURES. MOST CONVECTION CURRENTLY HAS BEEN DEVELOPING ALONG
THE COASTAL TROUGH AND NORTHEAST OF SURFACE LOW. MOST OF SOUTH TEXAS
REMAINS UNDER LARGE SCALE ASCENT WITH THE REGION UNDER THE RIGHT
REAR QUADRANT OF 100+ KNOT JET. HOWEVER BEST SURFACE CONVERGENCE IS
NOTED ALONG THE LEAD BOUNDARY AND SURFACE LOW. ANOTHER WEAK
DISTURBANCE IS APPROACHING THE COASTAL AREAS OF TAMAULIPAS WHICH
LOOKS TO PASS TO OUR SOUTH. GUT FEELING FROM CURRENT TRENDS IS FOR
THE MAJORITY OF THE CONVECTION TO REMAIN OFFSHORE WITH SOME ISOLATED
TO POSSIBLE SCATTERED ACTIVITY DEVELOPING OVER THE COASTAL COUNTIES
BEFORE SUNRISE.  AS THE SECOND FRONT MOVES INTO THE AREA THE BEST
MOISTURE WILL BE SHOVED EAST WITH LITTLE LEFT TO PRODUCE AS MUCH
RAIN AS WHAT IS CURRENTLY PROJECTED IN THE FORECAST. HAVE ALREADY
LOWERED RAIN CHANCES BUT HAVE REDUCE THE MENTION OF THUNDER EXCEPT
OVER KENEDY COUNTY AND THE GULF WATERS. TIMING OF THE SECOND FRONT
IN LINE WITH THE NAM MODEL WHICH IS ABOUT 3 HOURS SLOWER THEN THE
GFS. THE FRONT TO MOVE THROUGH THE NORTHERN ZONES AROUND OR SHORTLY
AFTER SUNRISE WORKING ITS WAY SOUTH OF BROWNSVILLE BY 10 AM. WE CAN
EXPECT OUR WINDS TO TURN NORTH TO NORTHWEST AHEAD OF THE SECOND
FRONT WITH A MORE NOTICEABLE AIRMASS CHANGE WITH STRONGER WIND AND
COOLING TEMPERATURES AS THE SECOND BOUNDARY PASSES THROUGH THE
REGION.  CURRENT OBSERVATIONS INDICATE A NICE COOL AIRMASS OVER
NORTH CENTRAL TEXAS AND SOME OF THAT AIR TO SPREAD SOUTH AS NORTH
WINDS INCREASE TO BREEZY LEVELS. EXPECT HIGH TEMPERATURES TO OCCUR
THIS MORNING WITH A SLOW STEADY FALL THROUGH THE AFTERNOON. ANY RAIN
THAT FALLS BEHIND THE FRONT WILL PROVIDE AN EVAPORATIVE COOLING
AFFECT WHICH WILL ALLOW FOR TEMPERATURES TO FALL MORE QUICKLY ALBEIT
FOR A SHORT WHILE. IN ANY CASE HAVE LOWERED TEMPERATURES A FEW
DEGREES AND IT WILL FEEL A BIT CHILLY WITH A GRAY OVERCAST HOLDING
TOUGH ALL DAY.

TONIGHT...COOL SURFACE HIGH BUILDS MORE OVER EAST TEXAS THEN OVER
OUR REGION WITH NORTH WINDS VEERING NORTHEAST AND DIMINISHING
RAPIDLY. THE COLD AIR ADVECTION DURING THE DAYTIME HOURS WILL BE
WEAKENING.  GUIDANCE TEMPERATURES HAVE LOWERED A FEW DEGREES OVER
PREVIOUS RUNS AND WITH EVIDENCE OF TEMPERATURES UPSTREAM WILL TREND
IN THIS DIRECTION EVEN WITH AN OVERCAST CONDITIONS. DO NOT EXPECT
THE CLOUDS TO CLEAR AS 700MB FLOW TURNS SOUTHWEST DEVELOPING WEAK
OVERRUNNING.

SUNDAY...HIGH PRESSURE MOVES WELL EAST AND UPPER FLOW REMAINS
WESTERLY WHICH WILL ALLOW FOR OUR AIRMASS TO BEGIN MODIFYING RATHER
QUICKLY. FRONT STALLS WELL SOUTH AND THE EXPECTED DEVELOPMENT OF A
COASTAL TROUGH MIGHT BE DELAYED BY 6 HOURS. THIS WILL KEEP OUR RAIN
CHANCES LOWER AND LIKELY OUT OVER THE GULF. A SHORTWAVE TROUGH IN
THE WESTERLY FLOW EVENTUALLY WORKS ITS WAY NEAR THE BIG BEND AREA
WITH THE SURFACE INFLECTION DEVELOPING LATER IN THE DAY OR IN THE
EVENING WITH RAIN CHANCES POSSIBLY INCREASE AFTER DARK. WINDS TO
VEER EAST AND TEMPERATURES TO WARM UP WITH SOME BREAKS IN THE
OVERCAST ESPECIALLY ACROSS THE NORTH AND WEST.  /59/

LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
BROAD UPPER-LEVEL TROUGHINESS WILL CONTINUE TO DOMINATE MUCH OF THE
CENTRAL AND EASTERN UNITED STATES AS WE HEAD INTO THE LONG TERM
PORTION OF THE FORECAST.  CLOSER TO HOME...IT LOOKS LIKE SHOWER
POSSIBILITIES WILL CONTINUE AS WE HEAD TOWARD THE START OF THE NEW
WORKWEEK AS A COASTAL TROUGH REMAINS IN PLACE.

LOW-LEVEL THETA-E VALUES WILL LIKELY APPROACH 340K DURING THIS
PERIOD...WITH PRECIPITABLE WATER VALUES RANGING FROM 1.8 INCHES NEAR
THE US-281 CORRIDOR TO A LITTLE MORE THAN 2 INCHES ALONG THE COAST
AND OFFSHORE.  THESE PRECIPITABLE WATER VALUES ARE ABOVE THE 75TH
PERCENTILE CLIMATOLOGICALLY.  IN OTHER WORDS...PLENTY OF MOISTURE
SHOULD BE SEEN THROUGH THE BOUNDARY LAYER SUNDAY NIGHT AND MONDAY.
COMBINED WITH THE PRESENCE OF THE COASTAL TROUGH...AT LEAST A
SCATTERING OF SHOWERS WILL LIKELY BE SEEN.

I HAVE A CONCERN OR TWO ABOUT THIS SCENARIO THOUGH.  MOST OF THE
ISENTROPIC ASCENT AND LOWER CONDENSATION PRESSURE DEFICITS /ALONG
THE 310K THETA SURFACE/ SHIFT OFFSHORE SUNDAY EVENING...WITH
ADDITIONAL MOISTURE MOVING INTO THIS REGION OVERNIGHT.  THE UPGLIDE
THEN STRENGTHENS AND STARTS TO MOVE NORTHEAST /AND AWAY FROM OUR
AREA/ MONDAY MORNING.  EVIDENCE OF THIS ALSO EXISTS IN THE QG
FIELDS...AS A MID-LEVEL SHORTWAVE TROUGH MOVES NORTHEAST THROUGH THE
REGION.

THIS IMPLIES TO ME TWO THINGS.  FIRST...THE BEST TIME TO SEE
PRECIPITATION FOR OUR REGION WILL LIKELY BE LATE SUNDAY NIGHT...
WITH DIMINISHING ODDS MONDAY MORNING.  THIS IS A TAD FASTER THAN
WHAT THE CURRENT FORECAST IMPLIES.  SECOND...THE ODDS OF SEEING
SHOWERS /MAINLY OVER LAND AREAS/ MAY NOT BE AS GREAT AS THE CURRENT
FORECAST.  WITH THIS FORECAST PACKAGE...I HAVE MADE SOME TWEAKS TO
TIMING BASED ON THE LATEST DATA.  PRECIPITATION PROBABILITIES HAVE
LARGELY REMAINED UNTOUCHED...AND WILL ALLOW SUBSEQUENT SHIFTS TO
FINE TUNE THE FORECAST USING THE LATEST AVAILABLE DATA.

CONDITIONS SHOULD START TO DRY OUT A BIT MONDAY AFTERNOON AND
EVENING...AS THE SURFACE TROUGH MOVES FARTHER OFFSHORE.  A SHORTWAVE
TROUGH IS EXPECTED TO SWING THROUGH THE SOUTHERN PLAINS MONDAY NIGHT
INTO TUESDAY MORNING.  THERE MAY BE ENOUGH MOMENTUM ASSOCIATED WITH
THIS FEATURE TO PUSH A WEAK COLD FRONT THROUGH THE AREA TUESDAY
MORNING.  SOME LOW CLOUDS MAY REMAIN IN PLACE BEHIND THE FRONT
THANKS TO A BIT OF LINGERING THERMAL TROUGHINESS AT 850MB.

THE UPPER TROUGH AXIS IS FORECAST TO SHIFT EAST WEDNESDAY.
NORTHWEST FLOW ALOFT OVER OUR AREA IN WAKE OF THIS SYSTEM SHOULD
ALLOW THE CENTER OF A SURFACE HIGH TO HEAD INTO THE OZARKS
WEDNESDAY.  WEAK SHORTWAVE RIDGING...COMBINED WITH A SURFACE HIGH
NEAR THE ARKLAMISS SHOULD ALLOW QUIET WEATHER CONDITIONS TO BE SEEN
FOR THE REMAINDER OF THE UPCOMING WORKWEEK.  /BUTTS/

MARINE...

TODAY THROUGH SUNDAY...
SMALL CRAFT ADVISORIES ARE IN PLACE FOR ALL COASTAL WATERS TODAY AS
NORTH WINDS TO INCREASE BEHIND A COLD FRONT POISED TO MOVE OFFSHORE
AFTER SUNRISE. SEAS TO RESPOND RATHER QUICKLY WITH ROUGH CONDITIONS
BY OR BEFORE NOON. HIGH PRESSURE TO BUILDS NORTH AND EAST OF THE
LOWER TEXAS COAST TONIGHT INTO SUNDAY WITH WINDS AND SEAS LOWERING.
SCA COULD PERSIST FOR THE OFFSHORE WATERS THIS EVENING BUT SHOULD
FALL BELOW CRITERIA BY MIDNIGHT. MORNING SHOWERS AND THUNDERSTORMS
TO FAVOR THE NORTHERN WATERS WITH AREAS OF RAIN WITH EMBEDDED
SHOWERS ACROSS THE SOUTH. MOST OF THE STORMS TO PUSH OFF TO THE
NORTHEAST BEFORE NOON.  /59/

SUNDAY NIGHT THROUGH WEDNESDAY...
A TROUGH OF LOW PRESSURE JUST OFFSHORE...COMBINED WITH AMPLE
MOISTURE...SHOULD ALLOW SHOWERS AND A FEW STORMS TO BE SEEN OVER THE
MARINE AREA SUNDAY NIGHT THROUGH MONDAY.  E WINDS /GENERALLY 10 KTS
OR LESS/ SHOULD BECOME SE SUNDAY NIGHT...THEN BECOME SW-W MONDAY
AFTERNOON AS THE TROUGH MOVES FARTHER OFFSHORE.  A WEAK COLD FRONT
IS FORECAST TO MOVE THROUGH THE MARINE AREA TUESDAY.  THIS IS
EXPECTED TO RESULT IN STRENGTHENING N-NE WINDS AND BUILDING SEAS.
SMALL CRAFT ADVISORIES MAY BE NEEDED FOR ALL OR PART OF THE MARINE
AREA DURING THIS TIME.  /BUTTS/

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...WIND ADVISORY UNTIL 2 PM CDT THIS AFTERNOON FOR TXZ256-257.

GM...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR GMZ130-132-
     135.

     SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 1 AM CDT SUNDAY
     FOR GMZ170-175.

     GALE WARNING UNTIL 4 PM CDT THIS AFTERNOON FOR GMZ170-175.

     SMALL CRAFT ADVISORY UNTIL 1 AM CDT SUNDAY FOR GMZ150-155.

&&

$$

THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV

68/61






AREA FORECAST DISCUSSION...UPDATED

NWS BROWNSVILLE TX

 749 AM CDT SAT OCT 19 2013

.DISCUSSION...12Z RAOB ANALYSIS AND SURFACE OBSERVATIONS SHOW MUCH
MORE EXTENSIVE 925/850MB COLD ADVECTION THAN WHAT WAS ORIGINALLY
ANTICIPATED WITH THIS COLD FRONT. BUOY OBSERVATIONS ARE PUSHING
GALE FORCE GUSTS IN THE LAST HOUR...AND BASED ON RAP AND OBSERVED
ANALYSIS STRONGER COLD ADVECTION/WIND IS EXPECTED THROUGH THE NEXT
FEW HOURS. WITH THAT UPGRADED THE OFFSHORE WATERS TO A GALE
WARNING THROUGH 4 PM THIS AFTERNOON FOR FREQUENT GALE FORCE GUSTS.
/68-JGG/

&&

.MARINE...HAVE UPGRADED THE SMALL CRAFT ADVISORY TO A GALE WARNING
FOR FREQUENT GALE FORCE GUSTS IN THE OFFSHORE ZONES.

&&

.PREV DISCUSSION... /ISSUED 651 AM CDT SAT OCT 19 2013/

DISCUSSION...UPDATED FOR LATEST MARINE DISCUSSION BELOW.

MARINE...HAVE MOVED UP THE STARTING TIME OF THE SCA WITH WINDS
BEHIND A LINE OF THUNDERSTORMS EXCEEDING SCA CRITERIA. DO NOT
BELIEVE THERE WILL BE MUCH OF LULL BEFORE HIGH PRESSURE BUILDS
TOWARDS THE COAST IN WAKE OF A COLD FRONT NOW MOVING ACROSS THE
NORTHERN RANCHLANDS. WINDS ACROSS THE LAGUNA MADRE WILL ALSO BE ON
THE INCREASE THIS EARLIER THIS MORNING.

PREV DISCUSSION... /ISSUED 628 AM CDT SAT OCT 19 2013/

DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.

AVIATION...IFR CIGS SPREADING ACROSS THE REGION EARLY THIS
MORNING. EXPECT CIGS TO LOWER AT KHRL AND KBRO BY OR SHORTLY AFTER
SUNRISE. THE LOWER CIGS TO PERSIST THROUGH THE MORNING WITH A SLOW
RISE TO MVFR THIS AFTERNOON. VFR CONDITIONS NOT EXPECTED AT THE
REGIONAL AIRPORTS UNTIL THE EVENING HOURS. HIGH PRESSURE BUILDS
SOUTH INCREASING THE NORTH WIND. GUSTS TO 25 KNOTS ARE POSSIBLE
WITH A STEADY 12-18 KNOT WIND THROUGH THE DAY.

PREV DISCUSSION... /ISSUED 426 AM CDT SAT OCT 19 2013/

SHORT TERM /NOW THROUGH SUNDAY/...
SURFACE OBSERVATIONS INDICATE TWO FRONTS ACROSS SOUTH TEXAS THIS
MORNING. THE LEAD STATIONARY FRONT PARALLELS THE COAST WITH A WEAK
SURFACE LOW OR FRONTAL WAVE EAST OF KENEDY COUNTY. THE SECOND FRONT
EXTENDS FROM NEAR SHREVEPORT TO COTULLA.

MAIN CHALLENGE FOR TODAY IS THE POP FORECAST FOLLOWED BY THE
TEMPERATURES. MOST CONVECTION CURRENTLY HAS BEEN DEVELOPING ALONG
THE COASTAL TROUGH AND NORTHEAST OF SURFACE LOW. MOST OF SOUTH TEXAS
REMAINS UNDER LARGE SCALE ASCENT WITH THE REGION UNDER THE RIGHT
REAR QUADRANT OF 100+ KNOT JET. HOWEVER BEST SURFACE CONVERGENCE IS
NOTED ALONG THE LEAD BOUNDARY AND SURFACE LOW. ANOTHER WEAK
DISTURBANCE IS APPROACHING THE COASTAL AREAS OF TAMAULIPAS WHICH
LOOKS TO PASS TO OUR SOUTH. GUT FEELING FROM CURRENT TRENDS IS FOR
THE MAJORITY OF THE CONVECTION TO REMAIN OFFSHORE WITH SOME ISOLATED
TO POSSIBLE SCATTERED ACTIVITY DEVELOPING OVER THE COASTAL COUNTIES
BEFORE SUNRISE.  AS THE SECOND FRONT MOVES INTO THE AREA THE BEST
MOISTURE WILL BE SHOVED EAST WITH LITTLE LEFT TO PRODUCE AS MUCH
RAIN AS WHAT IS CURRENTLY PROJECTED IN THE FORECAST. HAVE ALREADY
LOWERED RAIN CHANCES BUT HAVE REDUCE THE MENTION OF THUNDER EXCEPT
OVER KENEDY COUNTY AND THE GULF WATERS. TIMING OF THE SECOND FRONT
IN LINE WITH THE NAM MODEL WHICH IS ABOUT 3 HOURS SLOWER THEN THE
GFS. THE FRONT TO MOVE THROUGH THE NORTHERN ZONES AROUND OR SHORTLY
AFTER SUNRISE WORKING ITS WAY SOUTH OF BROWNSVILLE BY 10 AM. WE CAN
EXPECT OUR WINDS TO TURN NORTH TO NORTHWEST AHEAD OF THE SECOND
FRONT WITH A MORE NOTICEABLE AIRMASS CHANGE WITH STRONGER WIND AND
COOLING TEMPERATURES AS THE SECOND BOUNDARY PASSES THROUGH THE
REGION.  CURRENT OBSERVATIONS INDICATE A NICE COOL AIRMASS OVER
NORTH CENTRAL TEXAS AND SOME OF THAT AIR TO SPREAD SOUTH AS NORTH
WINDS INCREASE TO BREEZY LEVELS. EXPECT HIGH TEMPERATURES TO OCCUR
THIS MORNING WITH A SLOW STEADY FALL THROUGH THE AFTERNOON. ANY RAIN
THAT FALLS BEHIND THE FRONT WILL PROVIDE AN EVAPORATIVE COOLING
AFFECT WHICH WILL ALLOW FOR TEMPERATURES TO FALL MORE QUICKLY ALBEIT
FOR A SHORT WHILE. IN ANY CASE HAVE LOWERED TEMPERATURES A FEW
DEGREES AND IT WILL FEEL A BIT CHILLY WITH A GRAY OVERCAST HOLDING
TOUGH ALL DAY.

TONIGHT...COOL SURFACE HIGH BUILDS MORE OVER EAST TEXAS THEN OVER
OUR REGION WITH NORTH WINDS VEERING NORTHEAST AND DIMINISHING
RAPIDLY. THE COLD AIR ADVECTION DURING THE DAYTIME HOURS WILL BE
WEAKENING.  GUIDANCE TEMPERATURES HAVE LOWERED A FEW DEGREES OVER
PREVIOUS RUNS AND WITH EVIDENCE OF TEMPERATURES UPSTREAM WILL TREND
IN THIS DIRECTION EVEN WITH AN OVERCAST CONDITIONS. DO NOT EXPECT
THE CLOUDS TO CLEAR AS 700MB FLOW TURNS SOUTHWEST DEVELOPING WEAK
OVERRUNNING.

SUNDAY...HIGH PRESSURE MOVES WELL EAST AND UPPER FLOW REMAINS
WESTERLY WHICH WILL ALLOW FOR OUR AIRMASS TO BEGIN MODIFYING RATHER
QUICKLY. FRONT STALLS WELL SOUTH AND THE EXPECTED DEVELOPMENT OF A
COASTAL TROUGH MIGHT BE DELAYED BY 6 HOURS. THIS WILL KEEP OUR RAIN
CHANCES LOWER AND LIKELY OUT OVER THE GULF. A SHORTWAVE TROUGH IN
THE WESTERLY FLOW EVENTUALLY WORKS ITS WAY NEAR THE BIG BEND AREA
WITH THE SURFACE INFLECTION DEVELOPING LATER IN THE DAY OR IN THE
EVENING WITH RAIN CHANCES POSSIBLY INCREASE AFTER DARK. WINDS TO
VEER EAST AND TEMPERATURES TO WARM UP WITH SOME BREAKS IN THE
OVERCAST ESPECIALLY ACROSS THE NORTH AND WEST.  /59/

LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
BROAD UPPER-LEVEL TROUGHINESS WILL CONTINUE TO DOMINATE MUCH OF THE
CENTRAL AND EASTERN UNITED STATES AS WE HEAD INTO THE LONG TERM
PORTION OF THE FORECAST.  CLOSER TO HOME...IT LOOKS LIKE SHOWER
POSSIBILITIES WILL CONTINUE AS WE HEAD TOWARD THE START OF THE NEW
WORKWEEK AS A COASTAL TROUGH REMAINS IN PLACE.

LOW-LEVEL THETA-E VALUES WILL LIKELY APPROACH 340K DURING THIS
PERIOD...WITH PRECIPITABLE WATER VALUES RANGING FROM 1.8 INCHES NEAR
THE US-281 CORRIDOR TO A LITTLE MORE THAN 2 INCHES ALONG THE COAST
AND OFFSHORE.  THESE PRECIPITABLE WATER VALUES ARE ABOVE THE 75TH
PERCENTILE CLIMATOLOGICALLY.  IN OTHER WORDS...PLENTY OF MOISTURE
SHOULD BE SEEN THROUGH THE BOUNDARY LAYER SUNDAY NIGHT AND MONDAY.
COMBINED WITH THE PRESENCE OF THE COASTAL TROUGH...AT LEAST A
SCATTERING OF SHOWERS WILL LIKELY BE SEEN.

I HAVE A CONCERN OR TWO ABOUT THIS SCENARIO THOUGH.  MOST OF THE
ISENTROPIC ASCENT AND LOWER CONDENSATION PRESSURE DEFICITS /ALONG
THE 310K THETA SURFACE/ SHIFT OFFSHORE SUNDAY EVENING...WITH
ADDITIONAL MOISTURE MOVING INTO THIS REGION OVERNIGHT.  THE UPGLIDE
THEN STRENGTHENS AND STARTS TO MOVE NORTHEAST /AND AWAY FROM OUR
AREA/ MONDAY MORNING.  EVIDENCE OF THIS ALSO EXISTS IN THE QG
FIELDS...AS A MID-LEVEL SHORTWAVE TROUGH MOVES NORTHEAST THROUGH THE
REGION.

THIS IMPLIES TO ME TWO THINGS.  FIRST...THE BEST TIME TO SEE
PRECIPITATION FOR OUR REGION WILL LIKELY BE LATE SUNDAY NIGHT...
WITH DIMINISHING ODDS MONDAY MORNING.  THIS IS A TAD FASTER THAN
WHAT THE CURRENT FORECAST IMPLIES.  SECOND...THE ODDS OF SEEING
SHOWERS /MAINLY OVER LAND AREAS/ MAY NOT BE AS GREAT AS THE CURRENT
FORECAST.  WITH THIS FORECAST PACKAGE...I HAVE MADE SOME TWEAKS TO
TIMING BASED ON THE LATEST DATA.  PRECIPITATION PROBABILITIES HAVE
LARGELY REMAINED UNTOUCHED...AND WILL ALLOW SUBSEQUENT SHIFTS TO
FINE TUNE THE FORECAST USING THE LATEST AVAILABLE DATA.

CONDITIONS SHOULD START TO DRY OUT A BIT MONDAY AFTERNOON AND
EVENING...AS THE SURFACE TROUGH MOVES FARTHER OFFSHORE.  A SHORTWAVE
TROUGH IS EXPECTED TO SWING THROUGH THE SOUTHERN PLAINS MONDAY NIGHT
INTO TUESDAY MORNING.  THERE MAY BE ENOUGH MOMENTUM ASSOCIATED WITH
THIS FEATURE TO PUSH A WEAK COLD FRONT THROUGH THE AREA TUESDAY
MORNING.  SOME LOW CLOUDS MAY REMAIN IN PLACE BEHIND THE FRONT
THANKS TO A BIT OF LINGERING THERMAL TROUGHINESS AT 850MB.

THE UPPER TROUGH AXIS IS FORECAST TO SHIFT EAST WEDNESDAY.
NORTHWEST FLOW ALOFT OVER OUR AREA IN WAKE OF THIS SYSTEM SHOULD
ALLOW THE CENTER OF A SURFACE HIGH TO HEAD INTO THE OZARKS
WEDNESDAY.  WEAK SHORTWAVE RIDGING...COMBINED WITH A SURFACE HIGH
NEAR THE ARKLAMISS SHOULD ALLOW QUIET WEATHER CONDITIONS TO BE SEEN
FOR THE REMAINDER OF THE UPCOMING WORKWEEK.  /BUTTS/

MARINE...

TODAY THROUGH SUNDAY...
SMALL CRAFT ADVISORIES ARE IN PLACE FOR ALL COASTAL WATERS TODAY AS
NORTH WINDS TO INCREASE BEHIND A COLD FRONT POISED TO MOVE OFFSHORE
AFTER SUNRISE. SEAS TO RESPOND RATHER QUICKLY WITH ROUGH CONDITIONS
BY OR BEFORE NOON. HIGH PRESSURE TO BUILDS NORTH AND EAST OF THE
LOWER TEXAS COAST TONIGHT INTO SUNDAY WITH WINDS AND SEAS LOWERING.
SCA COULD PERSIST FOR THE OFFSHORE WATERS THIS EVENING BUT SHOULD
FALL BELOW CRITERIA BY MIDNIGHT. MORNING SHOWERS AND THUNDERSTORMS
TO FAVOR THE NORTHERN WATERS WITH AREAS OF RAIN WITH EMBEDDED
SHOWERS ACROSS THE SOUTH. MOST OF THE STORMS TO PUSH OFF TO THE
NORTHEAST BEFORE NOON.  /59/

SUNDAY NIGHT THROUGH WEDNESDAY...
A TROUGH OF LOW PRESSURE JUST OFFSHORE...COMBINED WITH AMPLE
MOISTURE...SHOULD ALLOW SHOWERS AND A FEW STORMS TO BE SEEN OVER THE
MARINE AREA SUNDAY NIGHT THROUGH MONDAY.  E WINDS /GENERALLY 10 KTS
OR LESS/ SHOULD BECOME SE SUNDAY NIGHT...THEN BECOME SW-W MONDAY
AFTERNOON AS THE TROUGH MOVES FARTHER OFFSHORE.  A WEAK COLD FRONT
IS FORECAST TO MOVE THROUGH THE MARINE AREA TUESDAY.  THIS IS
EXPECTED TO RESULT IN STRENGTHENING N-NE WINDS AND BUILDING SEAS.
SMALL CRAFT ADVISORIES MAY BE NEEDED FOR ALL OR PART OF THE MARINE
AREA DURING THIS TIME.  /BUTTS/

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR GMZ130-132-
     135.

     SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 1 AM CDT SUNDAY
     FOR GMZ170-175.

     GALE WARNING UNTIL 4 PM CDT THIS AFTERNOON FOR GMZ170-175.

     SMALL CRAFT ADVISORY UNTIL 1 AM CDT SUNDAY FOR GMZ150-155.

&&

$$

THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV

68/61






AREA FORECAST DISCUSSION

NWS HOUSTON/GALVESTON TX

 631 AM CDT SAT OCT 19 2013

.UPDATE...
EARLY MORNING UPDATE FOR RAIN MOVING OUT OF THE AREA.

&&

.DISCUSSION...
KEEPING UP WITH LATEST RADAR TRENDS HAVE UPDATED RAIN CHANCES FOR
THE DAY AS PRECIP CONTINUES TO MOVE EAST OUT INTO THE GULF. LOOKS
LIKE MOSTLY CLOUDY SKIES TO START THIS MORNING AS COLD FRONT
PUSHES THROUGH THE AREA. COLD FRONT CURRENTLY PUSHING THROUGH
CONROE AND APPROACHING THE HOUSTON AREA. FRONT SHOULD PUSH OFF THE
COAST MID MORNING. UPDATED FORECAST PRODUCTS HAVE BEEN ISSUED.

39

&&

.PREV DISCUSSION... /ISSUED 608 AM CDT SAT OCT 19 2013/

DISCUSSION...
SEE AVIATION FOR 12Z TAF DISCUSSION

AVIATION...
SHRA HAVE MOVED OFFSHORE THIS MORNING AND ALL PRECIP MENTIONS WILL
BE REMOVED FROM THE TAFS. NORTHERLY WINDS ALREADY ONGOING AT ALL
SITES AS PREFRONTAL TROUGH HAS PUSHED OFFSHORE WITH THE ACTUAL
COLD FRONT HAVING REACHED CLL AND UTS THIS MORNING. EXPECT AN HOUR
OR TWO WITH GUSTS NEAR 20KTS AS THE FRONTAL BOUNDARY PUSHES
THROUGH THIS MORNING. MAIN CONCERN WILL BE SOUTHERLY EXTENT OF
IFR/MVFR CIGS IMMEDIATELY BEHIND THE FRONT. AS THE SUN COMES UP
THIS MORNING FEEL THAT THIS LAYER WILL BEGIN TO SCATTER OUT SO
HAVE NOT INCLUDED CIGS FOR IAH ALTHOUGH A BRIEF PERIOD OF
BKN010-BKN015 IS POSSIBLE THIS MORNING BEFORE CONDITIONS IMPROVE
TO VFR BY AFTERNOON. SURFACE HIGH PRESSURE WILL SPREAD INTO
SOUTHEAST TEXAS SATURDAY EVENING LEADING TO VARIABLE WINDS ACROSS
THE INLAND AREAS OVERNIGHT INTO SUNDAY. 38

PREV DISCUSSION... /ISSUED 428 AM CDT SAT OCT 19 2013/

DISCUSSION...
COLD FRONT PUSHING SOUTH THROUGH TEXAS AT 09Z (4AM CDT) ABOUT AT
A KLFK/KUTS/K11R LINE OR BASICALLY A BRENHAM TO LUFKIN LINE. LINE
OF SHOWERS AND THUNDERSTORMS OVER HOUSTON EARLIER TONIGHT HAS
WEAKENED AND ACTIVITY HAS INCREASED MORE OFF THE UPPER TX COAST.
UPPER LEVEL SHORT WAVE LOOKS TO BE MOVING OUT OF THE AREA AND
POSSIBLE THAT UPPER LEVEL DIVERGENCE IS WEAKENING AS A RESULT.
BULK OF EARLIER CONVECTION HAS BEEN SUPPORTED BY SOME ISENTROPIC
LIFT AND FRONTOGENESIS IN 925-850MB LAYER PER SPC MESOANALYSES.
PER LATEST RADAR TRENDS...EXPECT SOME LINGERING SHOWERS ALONG THE
COAST BUT LOOKS LIKE MOST OF THE RAINFALL MAY BE DONE BY 12Z WHICH
IS A GOOD 3-6 HRS SOONER THAN MOST 00Z MODEL SOLUTIONS. HOWEVER
THE 00Z TX TECH 3KM WRF AND LATEST 06Z HRRR ARE IN GOOD AGREEMENT
WITH LATEST TRENDS. FORECAST HAS BE TRENDED TOWARDS THESE MODELS
IN THE SHORT TERM BUT MAY HOLD ONTO PRECIP A LITTLE LONGER. COLD
FRONT SHOULD BE OFF THE COAST BETWEEN 12-15Z THIS MORNING WITH
STRONG NORTHERLY WINDS ARE WIDE. UPPER LEVEL TROUGH AXIS WILL ALSO
HAVE PUSHED BY SE TX WITH RIGHT REAR QUADRANT OF JET STREAK STILL
LINGERING OVER THE AREA. HIGH PRESSURE AT THE SURFACE SHOULD
CONTINUE TO BUILD OVER TX TODAY. MAX TEMPS WILL BE A CHALLENGE AS
DO EXPECT SOME COLD ADVECTION TO OCCUR. HOWEVER 850MB TEMPS ONLY
DROP TO ABOUT 12-13C SO COULD STILL SEE TEMPS REACHING UPPER 60S
TO LOW 70S WITH DAYTIME HEATING. CLOUD COVER SHOULD CLEAR OUT SO
MAY NOT GET QUITE AS COOL AS IT COULD WITH BULK OF COLDER AIRMASS
MOVING EAST OF THE AREA OVER MISS RIVER VALLEY.

LOOKS LIKE RETURN FLOW AND WARM ADVECTION WILL ENSUE ONCE AGAIN
SUN NIGHT INTO MONDAY. VERY SIMILAR SET UP TO THE MOST RECENT RAIN
EVENT WITH WEAK ISENTROPIC LIFT AND A SHORT WAVE TROUGH ROTATING
THROUGH THE S PLAINS PROVIDING ENOUGH LARGE SCALE ASCENT FOR
ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. THINK ORIENTATION OF
JET STREAK AND SHORT WAVE TROUGH MAY PUSH BULK OF PRECIP EAST OF
SE TX SO HAVE NOT CHANGED POPS MUCH. BEST CHANCES WILL AGAIN BE
ALONG THE COAST BUT WILL KEEP AROUND 50 PERCENT FOR NOW. ANOTHER
COLD FRONT WILL ALSO PUSH INTO SE TX BUT MORE SO MON NIGHT INTO
TUE MORNING. BEST LIFT WILL HAVE SHIFTED EAST BY THIS TIME SO WILL
BE HAVING DECREASING RAIN CHANCES MON NIGHT INTO TUE.

TUE THROUGH THE REST OF THE WEEK SHOULD BE DRY WITH A RATHER
AMPLIFIED UPPER LEVEL PATTERN. BROAD RIDGE SHOULD REMAIN OVER THE
PACIFIC COAST WITH A DEEP LOW AND LONG WAVE TROUGH OVER THE GREAT
LAKES AND MIDWEST. SEVERAL SHORT WAVE TROUGHS MOVING THROUGH THE
FLOW SHOULD KEEP THE TROUGH OVER THE GREAT LAKES THROUGH THE END
OF THE WEEK. WILL GET SFC HIGH PRESSURE BUILDING OVER TX THROUGH
WED WITH ANOTHER RIDGE BUILDING OVER THE MIDWEST THUR INTO FRI.
PATTERN SHOULD KEEP CONDITIONS DRY AND ON THE COOL SIDE. TRIED TO
BLEND THE TEMP FORECAST BETWEEN GFS AND ENSEMBLE MEAN TEMPS FOR
THE LATER HALF OF THE WEEK. THIS WILL MEAN TEMPS WILL BE NEAR OR
EVEN A DEGREE OR TWO BELOW NORMAL FOR THE END OF NEXT WEEK.

39

MARINE...
NORTHERLY WINDS HAVE REACHED THE NEARSHORE BUOY THIS MORNING AS A
PREFRONTAL TROUGH PUSHES OUT AHEAD OF THE COLD FRONT MOVING INTO
SOUTHEAST TEXAS. EXPECT OFFSHORE WINDS TO PICK UP THROUGH THE
MORNING WITH BUILDING SEAS AS THE FRONT MOVES OFFSHORE. ADVISORY
FLAGS IN PLACE ACROSS ALL COASTAL WATERS TODAY AND MAY NEED TO BE
EXTENDED FURTHER STILL...ALTHOUGH WILL ALLOW NEXT SHIFT TO
EVALUATE NEW MODEL DATA AND OBSERVATIONS FROM TODAY BEFORE MAKING
THAT DECISION. EXPECT A QUICK RETURN OF ONSHORE WINDS LATE THIS
WEEKEND AHEAD OF YET ANOTHER FRONTAL PASSAGE EXPECTED LATE MONDAY
INTO TUESDAY. 38

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      68  45  75  58  78 /  10  10   0  10  20
HOUSTON (IAH)              72  47  77  59  78 /  10  10   0  10  40
GALVESTON (GLS)            74  58  76  68  79 /  10  10  10  20  50

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 4 PM CDT THIS
     AFTERNOON FOR THE FOLLOWING ZONES: GALVESTON BAY...
     MATAGORDA BAY.

     SMALL CRAFT ADVISORY UNTIL 6 PM CDT THIS EVENING FOR THE
     FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
     CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE
     MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
     TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH ISLAND TO
     FREEPORT OUT 20 NM.

&&

$$

DISCUSSION...39




AREA FORECAST DISCUSSION

NWS HOUSTON/GALVESTON TX

 608 AM CDT SAT OCT 19 2013

.DISCUSSION...
SEE AVIATION FOR 12Z TAF DISCUSSION

&&

.AVIATION...
SHRA HAVE MOVED OFFSHORE THIS MORNING AND ALL PRECIP MENTIONS WILL
BE REMOVED FROM THE TAFS. NORTHERLY WINDS ALREADY ONGOING AT ALL
SITES AS PREFRONTAL TROUGH HAS PUSHED OFFSHORE WITH THE ACTUAL
COLD FRONT HAVING REACHED CLL AND UTS THIS MORNING. EXPECT AN HOUR
OR TWO WITH GUSTS NEAR 20KTS AS THE FRONTAL BOUNDARY PUSHES
THROUGH THIS MORNING. MAIN CONCERN WILL BE SOUTHERLY EXTENT OF
IFR/MVFR CIGS IMMEDIATELY BEHIND THE FRONT. AS THE SUN COMES UP
THIS MORNING FEEL THAT THIS LAYER WILL BEGIN TO SCATTER OUT SO
HAVE NOT INCLUDED CIGS FOR IAH ALTHOUGH A BRIEF PERIOD OF
BKN010-BKN015 IS POSSIBLE THIS MORNING BEFORE CONDITIONS IMPROVE
TO VFR BY AFTERNOON. SURFACE HIGH PRESSURE WILL SPREAD INTO
SOUTHEAST TEXAS SATURDAY EVENING LEADING TO VARIABLE WINDS ACROSS
THE INLAND AREAS OVERNIGHT INTO SUNDAY. 38

&&

.PREV DISCUSSION... /ISSUED 428 AM CDT SAT OCT 19 2013/

DISCUSSION...
COLD FRONT PUSHING SOUTH THROUGH TEXAS AT 09Z (4AM CDT) ABOUT AT
A KLFK/KUTS/K11R LINE OR BASICALLY A BRENHAM TO LUFKIN LINE. LINE
OF SHOWERS AND THUNDERSTORMS OVER HOUSTON EARLIER TONIGHT HAS
WEAKENED AND ACTIVITY HAS INCREASED MORE OFF THE UPPER TX COAST.
UPPER LEVEL SHORT WAVE LOOKS TO BE MOVING OUT OF THE AREA AND
POSSIBLE THAT UPPER LEVEL DIVERGENCE IS WEAKENING AS A RESULT.
BULK OF EARLIER CONVECTION HAS BEEN SUPPORTED BY SOME ISENTROPIC
LIFT AND FRONTOGENESIS IN 925-850MB LAYER PER SPC MESOANALYSES.
PER LATEST RADAR TRENDS...EXPECT SOME LINGERING SHOWERS ALONG THE
COAST BUT LOOKS LIKE MOST OF THE RAINFALL MAY BE DONE BY 12Z WHICH
IS A GOOD 3-6 HRS SOONER THAN MOST 00Z MODEL SOLUTIONS. HOWEVER
THE 00Z TX TECH 3KM WRF AND LATEST 06Z HRRR ARE IN GOOD AGREEMENT
WITH LATEST TRENDS. FORECAST HAS BE TRENDED TOWARDS THESE MODELS
IN THE SHORT TERM BUT MAY HOLD ONTO PRECIP A LITTLE LONGER. COLD
FRONT SHOULD BE OFF THE COAST BETWEEN 12-15Z THIS MORNING WITH
STRONG NORTHERLY WINDS ARE WIDE. UPPER LEVEL TROUGH AXIS WILL ALSO
HAVE PUSHED BY SE TX WITH RIGHT REAR QUADRANT OF JET STREAK STILL
LINGERING OVER THE AREA. HIGH PRESSURE AT THE SURFACE SHOULD
CONTINUE TO BUILD OVER TX TODAY. MAX TEMPS WILL BE A CHALLENGE AS
DO EXPECT SOME COLD ADVECTION TO OCCUR. HOWEVER 850MB TEMPS ONLY
DROP TO ABOUT 12-13C SO COULD STILL SEE TEMPS REACHING UPPER 60S
TO LOW 70S WITH DAYTIME HEATING. CLOUD COVER SHOULD CLEAR OUT SO
MAY NOT GET QUITE AS COOL AS IT COULD WITH BULK OF COLDER AIRMASS
MOVING EAST OF THE AREA OVER MISS RIVER VALLEY.

LOOKS LIKE RETURN FLOW AND WARM ADVECTION WILL ENSUE ONCE AGAIN
SUN NIGHT INTO MONDAY. VERY SIMILAR SET UP TO THE MOST RECENT RAIN
EVENT WITH WEAK ISENTROPIC LIFT AND A SHORT WAVE TROUGH ROTATING
THROUGH THE S PLAINS PROVIDING ENOUGH LARGE SCALE ASCENT FOR
ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. THINK ORIENTATION OF
JET STREAK AND SHORT WAVE TROUGH MAY PUSH BULK OF PRECIP EAST OF
SE TX SO HAVE NOT CHANGED POPS MUCH. BEST CHANCES WILL AGAIN BE
ALONG THE COAST BUT WILL KEEP AROUND 50 PERCENT FOR NOW. ANOTHER
COLD FRONT WILL ALSO PUSH INTO SE TX BUT MORE SO MON NIGHT INTO
TUE MORNING. BEST LIFT WILL HAVE SHIFTED EAST BY THIS TIME SO WILL
BE HAVING DECREASING RAIN CHANCES MON NIGHT INTO TUE.

TUE THROUGH THE REST OF THE WEEK SHOULD BE DRY WITH A RATHER
AMPLIFIED UPPER LEVEL PATTERN. BROAD RIDGE SHOULD REMAIN OVER THE
PACIFIC COAST WITH A DEEP LOW AND LONG WAVE TROUGH OVER THE GREAT
LAKES AND MIDWEST. SEVERAL SHORT WAVE TROUGHS MOVING THROUGH THE
FLOW SHOULD KEEP THE TROUGH OVER THE GREAT LAKES THROUGH THE END
OF THE WEEK. WILL GET SFC HIGH PRESSURE BUILDING OVER TX THROUGH
WED WITH ANOTHER RIDGE BUILDING OVER THE MIDWEST THUR INTO FRI.
PATTERN SHOULD KEEP CONDITIONS DRY AND ON THE COOL SIDE. TRIED TO
BLEND THE TEMP FORECAST BETWEEN GFS AND ENSEMBLE MEAN TEMPS FOR
THE LATER HALF OF THE WEEK. THIS WILL MEAN TEMPS WILL BE NEAR OR
EVEN A DEGREE OR TWO BELOW NORMAL FOR THE END OF NEXT WEEK.

39

MARINE...
NORTHERLY WINDS HAVE REACHED THE NEARSHORE BUOY THIS MORNING AS A
PREFRONTAL TROUGH PUSHES OUT AHEAD OF THE COLD FRONT MOVING INTO
SOUTHEAST TEXAS. EXPECT OFFSHORE WINDS TO PICK UP THROUGH THE
MORNING WITH BUILDING SEAS AS THE FRONT MOVES OFFSHORE. ADVISORY
FLAGS IN PLACE ACROSS ALL COASTAL WATERS TODAY AND MAY NEED TO BE
EXTENDED FURTHER STILL...ALTHOUGH WILL ALLOW NEXT SHIFT TO
EVALUATE NEW MODEL DATA AND OBSERVATIONS FROM TODAY BEFORE MAKING
THAT DECISION. EXPECT A QUICK RETURN OF ONSHORE WINDS LATE THIS
WEEKEND AHEAD OF YET ANOTHER FRONTAL PASSAGE EXPECTED LATE MONDAY
INTO TUESDAY. 38

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      68  45  75  58  78 /  10  10   0  10  20
HOUSTON (IAH)              72  47  77  59  78 /  20  10   0  10  40
GALVESTON (GLS)            74  58  76  68  79 /  40  10  10  20  50

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 4 PM CDT THIS
     AFTERNOON FOR THE FOLLOWING ZONES: GALVESTON BAY...
     MATAGORDA BAY.

     SMALL CRAFT ADVISORY UNTIL 6 PM CDT THIS EVENING FOR THE
     FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
     CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE
     MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
     TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH ISLAND TO
     FREEPORT OUT 20 NM.

&&

$$

DISCUSSION...39
AVIATION/MARINE...38




AREA FORECAST DISCUSSION

NWS HOUSTON/GALVESTON TX

 428 AM CDT SAT OCT 19 2013

.DISCUSSION...
COLD FRONT PUSHING SOUTH THROUGH TEXAS AT 09Z (4AM CDT) ABOUT AT
A KLFK/KUTS/K11R LINE OR BASICALLY A BRENHAM TO LUFKIN LINE. LINE
OF SHOWERS AND THUNDERSTORMS OVER HOUSTON EARLIER TONIGHT HAS
WEAKENED AND ACTIVITY HAS INCREASED MORE OFF THE UPPER TX COAST.
UPPER LEVEL SHORT WAVE LOOKS TO BE MOVING OUT OF THE AREA AND
POSSIBLE THAT UPPER LEVEL DIVERGENCE IS WEAKENING AS A RESULT.
BULK OF EARLIER CONVECTION HAS BEEN SUPPORTED BY SOME ISENTROPIC
LIFT AND FRONTOGENESIS IN 925-850MB LAYER PER SPC MESOANALYSES.
PER LATEST RADAR TRENDS...EXPECT SOME LINGERING SHOWERS ALONG THE
COAST BUT LOOKS LIKE MOST OF THE RAINFALL MAY BE DONE BY 12Z WHICH
IS A GOOD 3-6 HRS SOONER THAN MOST 00Z MODEL SOLUTIONS. HOWEVER
THE 00Z TX TECH 3KM WRF AND LATEST 06Z HRRR ARE IN GOOD AGREEMENT
WITH LATEST TRENDS. FORECAST HAS BE TRENDED TOWARDS THESE MODELS
IN THE SHORT TERM BUT MAY HOLD ONTO PRECIP A LITTLE LONGER. COLD
FRONT SHOULD BE OFF THE COAST BETWEEN 12-15Z THIS MORNING WITH
STRONG NORTHERLY WINDS ARE WIDE. UPPER LEVEL TROUGH AXIS WILL ALSO
HAVE PUSHED BY SE TX WITH RIGHT REAR QUADRANT OF JET STREAK STILL
LINGERING OVER THE AREA. HIGH PRESSURE AT THE SURFACE SHOULD
CONTINUE TO BUILD OVER TX TODAY. MAX TEMPS WILL BE A CHALLENGE AS
DO EXPECT SOME COLD ADVECTION TO OCCUR. HOWEVER 850MB TEMPS ONLY
DROP TO ABOUT 12-13C SO COULD STILL SEE TEMPS REACHING UPPER 60S
TO LOW 70S WITH DAYTIME HEATING. CLOUD COVER SHOULD CLEAR OUT SO
MAY NOT GET QUITE AS COOL AS IT COULD WITH BULK OF COLDER AIRMASS
MOVING EAST OF THE AREA OVER MISS RIVER VALLEY.

LOOKS LIKE RETURN FLOW AND WARM ADVECTION WILL ENSUE ONCE AGAIN
SUN NIGHT INTO MONDAY. VERY SIMILAR SET UP TO THE MOST RECENT RAIN
EVENT WITH WEAK ISENTROPIC LIFT AND A SHORT WAVE TROUGH ROTATING
THROUGH THE S PLAINS PROVIDING ENOUGH LARGE SCALE ASCENT FOR
ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. THINK ORIENTATION OF
JET STREAK AND SHORT WAVE TROUGH MAY PUSH BULK OF PRECIP EAST OF
SE TX SO HAVE NOT CHANGED POPS MUCH. BEST CHANCES WILL AGAIN BE
ALONG THE COAST BUT WILL KEEP AROUND 50 PERCENT FOR NOW. ANOTHER
COLD FRONT WILL ALSO PUSH INTO SE TX BUT MORE SO MON NIGHT INTO
TUE MORNING. BEST LIFT WILL HAVE SHIFTED EAST BY THIS TIME SO WILL
BE HAVING DECREASING RAIN CHANCES MON NIGHT INTO TUE.

TUE THROUGH THE REST OF THE WEEK SHOULD BE DRY WITH A RATHER
AMPLIFIED UPPER LEVEL PATTERN. BROAD RIDGE SHOULD REMAIN OVER THE
PACIFIC COAST WITH A DEEP LOW AND LONG WAVE TROUGH OVER THE GREAT
LAKES AND MIDWEST. SEVERAL SHORT WAVE TROUGHS MOVING THROUGH THE
FLOW SHOULD KEEP THE TROUGH OVER THE GREAT LAKES THROUGH THE END
OF THE WEEK. WILL GET SFC HIGH PRESSURE BUILDING OVER TX THROUGH
WED WITH ANOTHER RIDGE BUILDING OVER THE MIDWEST THUR INTO FRI.
PATTERN SHOULD KEEP CONDITIONS DRY AND ON THE COOL SIDE. TRIED TO
BLEND THE TEMP FORECAST BETWEEN GFS AND ENSEMBLE MEAN TEMPS FOR
THE LATER HALF OF THE WEEK. THIS WILL MEAN TEMPS WILL BE NEAR OR
EVEN A DEGREE OR TWO BELOW NORMAL FOR THE END OF NEXT WEEK.

39

&&

.MARINE...
NORTHERLY WINDS HAVE REACHED THE NEARSHORE BUOY THIS MORNING AS A
PREFRONTAL TROUGH PUSHES OUT AHEAD OF THE COLD FRONT MOVING INTO
SOUTHEAST TEXAS. EXPECT OFFSHORE WINDS TO PICK UP THROUGH THE
MORNING WITH BUILDING SEAS AS THE FRONT MOVES OFFSHORE. ADVISORY
FLAGS IN PLACE ACROSS ALL COASTAL WATERS TODAY AND MAY NEED TO BE
EXTENDED FURTHER STILL...ALTHOUGH WILL ALLOW NEXT SHIFT TO
EVALUATE NEW MODEL DATA AND OBSERVATIONS FROM TODAY BEFORE MAKING
THAT DECISION. EXPECT A QUICK RETURN OF ONSHORE WINDS LATE THIS
WEEKEND AHEAD OF YET ANOTHER FRONTAL PASSAGE EXPECTED LATE MONDAY
INTO TUESDAY. 38

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      68  45  75  58  78 /  10  10   0  10  20
HOUSTON (IAH)              72  47  77  59  78 /  20  10   0  10  40
GALVESTON (GLS)            74  58  76  68  79 /  40  10  10  20  50

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 4 PM CDT THIS
     AFTERNOON FOR THE FOLLOWING ZONES: GALVESTON BAY...
     MATAGORDA BAY.

     SMALL CRAFT ADVISORY UNTIL 6 PM CDT THIS EVENING FOR THE
     FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
     CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE
     MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
     TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH ISLAND TO
     FREEPORT OUT 20 NM.

&&

$$

DISCUSSION...39
AVIATION/MARINE...38




AREA FORECAST DISCUSSION...UPDATED

NWS MILWAUKEE/SULLIVAN WI

 1012 AM CDT SAT OCT 19 2013

.UPDATE...BROKEN LINE OF SHOWERS WILL EXIT SOUTHEAST WISCONSIN
AROUND MIDDAY AS NEXT ROUND OF SHOWERS MOVES INTO SW WI. SHOWERS
WILL DIMINISH WEST TO EAST DURING THE EVENING AS MID LEVEL TROUGH
AND SURFACE TROUGH PUSH OFF TO THE EAST. 925MB HEIGHTS SUPPORT
HIGHS AROUND 50.

&&

.AVIATION/18Z TAFS/...A FEW SHOWERS OUT THERE RIGHT NOW...BUT BEST
CHANCE FOR SHOWERS WILL BE THIS AFTERNOON AS ANOTHER SHORTWAVE
PUSHES INTO SOUTHERN WISCONSIN. BASED ON LATEST SOUNDINGS AND
UPSTREAM OBS...COULD SEE CIGS BRIEFLY DROP TO MVFR AS THE
SHORTWAVE MOVES THROUGH.

SHOULD BE SOME CLEARING TONIGHT BEHIND THE SHORTWAVE. MORE SHOWERS
ARE THEN POSSIBLE SUNDAY AFTERNOON AND EVENING...THE BEST CHANCE
NORTH OF A LINE FROM DARLINGTON TO MILWAUKEE.

&&

.PREV DISCUSSION... /ISSUED 326 AM CDT SAT OCT 19 2013/

TODAY...FORECAST CONFIDENCE IS HIGH.

FULL LATITUDE TROUGH PHASING JUST ABOUT OVERHEAD CURRENTLY WITH
110 METER 500 MB HEIGHT FALLS CENTERED OVER NORTHERN ILLINOIS
FIRST THING THIS MORNING. DEVELOPING BAROCLINIC LEAF AND SWATH OF
LIGHT PRECIPITATION SHOULD STAY TO THE SOUTH AND EAST.

CIRCULATION WITH DIGGING UPSTREAM TROUGH NOW ALONG MN/ND BORDER
HAS PV1.5 SURFACE POKING BELOW 500 MB AND THIS IS EXPECTED TO MOVE
INTO SOUTHEAST MINNESOTA THIS MORNING AND ACROSS SOUTHERN
WISCONSIN THIS AFTERNOON. EVEN THOUGH HEIGHTS STOP FALLING DURING
THE DAY THE 500 MB COLD CORE OF -30C MOVES ACROSS DURING PEAK
DIURNAL HEATING...WITH MODELS SHOWING STEEP LAPSE RATES IN THE LOW
LEVELS.

LATEST HRRR SHOWS BANDS OF CONVECTIVE SHOWERS MOVING ACROSS DURING
THE LATE MORNING AND AFTERNOON WHICH SEEMS REASONABLE. WOULD NOT
BE SURPRISED IF THERE IS GRAUPEL MIXED IN GIVEN THE LOW FREEZING
LEVEL WITH THE HEAVIER SHOWERS.

TONIGHT...FORECAST CONFIDENCE IS HIGH.

HEIGHTS RISE ABOUT 90 METERS OVERNIGHT AND MODELS SHOW SIGNIFICANT
MID LEVEL DRYING DURING THE NIGHT. PROBABLY WILL NOT COMPLETELY
CLEAR OUT BUT BREAKS IN CLOUDS AND LIGHT WINDS FROM LATE EVENING
INTO THE 3-4 AM PERIOD SHOULD BE SUFFICIENT FOR READINGS TO DROP
TO AROUND FREEZING. MARGINAL NATURE OF EVENT SUGGESTS THAT A FROST
ADVISORY WOULD WORK BEST.

SUNDAY THROUGH MONDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM TO
HIGH.

SHORT TERM MODELS IN DECENT AGREEMENT WITH FEATURES DURING THIS
PERIOD. SURFACE LOW PRESSURE TRACKS FROM SOUTHEASTERN NORTH DAKOTA
TO NORTHWEST WISCONSIN SUNDAY...THEN INTO NORTHERN LAKE SUPERIOR
SUNDAY NIGHT. FOCUSED WARM AIR ADVECTION SPREADS THROUGH THE
REGION AHEAD OF THE LOW ON SUNDAY...WITH A STRONG COLD FRONT
PUSHING EAST THROUGH THE AREA LATE SUNDAY/SUNDAY EVENING.

GOOD LOW LEVEL Q VECTOR CONVERGENCE ALSO SEEN SUNDAY ACROSS THE
AREA. AREA FORECAST SOUNDINGS SHOWING GOOD MID LEVEL MOISTURE
SUNDAY...WITH LOW LEVELS SLOWLY TRYING TO MOISTEN BY LATE IN THE
DAY AND EARLY SUNDAY EVENING. BEST UPWARD VERTICAL MOTION AND DEEP
MOISTURE IS TOWARD CENTRAL WISCONSIN...THOUGH QPF DOES PASS
THROUGH MOST OF THE AREA EXCEPT THE FAR SOUTH.

HAVE LIKELY POPS IN THE FAR NORTHWEST COUNTIES LATER SUNDAY
AFTERNOON...WITH HIGHER END CHANCE POPS SUNDAY INTO SUNDAY EVENING
ACROSS THE NORTHERN HALF OF THE AREA. LOW POPS WERE KEPT IN THE
SOUTH. TEMPERATURE PROFILES WILL BE WARM ENOUGH FOR ALL RAIN.

HIGHS IN THE 50S ARE EXPECTED SUNDAY...BEFORE COLD AIR ADVECTION
WITH BRISK WEST WINDS BEHIND COLD FRONT BRINGS COLDER AIRMASS INTO
THE REGION. LOWS SHOULD DROP INTO THE MID TO UPPER 30S SUNDAY
NIGHT. QUIET WEATHER BUT CHILLY DAY EXPECTED ON MONDAY...WITH
HIGHS ONLY IN THE 40S WITH BRISK WEST WINDS CONTINUING.

ADDED LOW POPS FOR LIGHT RAIN/SNOW SHOWERS IN THE FAR NORTH AND
NORTHEAST COUNTIES MONDAY NIGHT...WITH PASSING 500MB VORTICITY
MAXIMUM WITHIN LARGER CYCLONIC FLOW. GOOD SHOT AT FREEZE WARNING
CRITERIA FOR MONDAY NIGHT...AS LOWS SHOULD DROP INTO THE UPPER 20S
TO LOWER 30S ACROSS THE AREA...WITH DECREASING WEST WINDS. LATER
SHIFTS MAY CONSIDER A FREEZE WATCH FOR THE ENTIRE AREA FOR MONDAY
NIGHT.

TUESDAY THROUGH FRIDAY...FORECAST CONFIDENCE IS MEDIUM.

ECMWF/GFS SHOWING SOME DIFFERENCES DURING THIS PERIOD. THEY SHOW
A GENERAL NORTHWEST FLOW AT 500MB CONTINUING THROUGH THE
WEEK...WITH SEVERAL VORTICITY MAXIMA SHIFTING THROUGH THE REGION.
THERE ARE TIMING DIFFERENCES WITH THESE FEATURES BETWEEN
ECMWF/GFS.

AT THE SURFACE...WEAK LOW PRESSURE PASSES WELL SOUTHWEST OF THE
AREA TUESDAY ON THE ECMWF/GFS. THEY BOTH THEN BRING HIGH PRESSURE
SOUTHEAST ACROSS THE CENTRAL PLAINS TUESDAY NIGHT. GFS THEN BRINGS
ANOTHER LOW SOUTHEAST THROUGH THE AREA LATER WEDNESDAY AND
WEDNESDAY EVENING...NOT SHOWN ON THE ECMWF.

BOTH MODELS THEN BRING HIGH PRESSURE SOUTHEAST THROUGH THE CENTRAL
PLAINS AGAIN THURSDAY INTO FRIDAY. THEY BOTH DO MAINTAIN THE COLD
AIRMASS OVER THE REGION. FOLLOWED CONSENSUS POPS AND TEMPERATURES
FOR THIS PERIOD. HIGHS SHOULD ONLY REACH THE 40S TUESDAY INTO
FRIDAY. LOWS SHOULD REMAIN IN THE UPPER 20S TO LOWER 30S
INLAND...WITH LOWER TO MID 30S LAKESIDE.

AVIATION/12Z TAFS/...

VFR MID LEVEL CLOUDS ARE EXPECTED MUCH OF THE TIME. UNSTABLE
CONDITIONS DURING THE LATE MORNING AND AFTERNOON WILL RESULT IN
CONVECTIVE SHOWERS WITH LOCALLY GUSTY WINDS...SMALL HAIL...AND
BRIEF MVFR CONDITIONS. THESE CONDITIONS WILL BE MOST LIKELY IN THE
KMSN AREA AND SOMEWHAT LESS LIKELY UNTIL LATE AFTERNOON IN THE
SOUTHEAST TAF SITES.

PARTIAL CLEARING IS EXPECTED TONIGHT WITH VFR CONDITIONS.

MARINE...

LAKE TO 850 MB TEMPERATURE DIFFERENCE INCREASES TO ABOUT 19 THIS
AFTERNOON AS COLD CORE MOVES ACROSS LAKE MICHIGAN. WESTERLY FLOW
REGIME SUGGESTS THAT WATERSPOUT THREAT SHOULD BE CONFINED MAINLY
TO CENTRAL AND EASTERN PORTION OF THE LAKE WHICH WOULD INCLUDE
EXTREME EASTERN PORTIONS OF THE OPEN WATERS.

FAST MOVING LOW ON SUNDAY WILL MOVE ACROSS WISCONSIN AND THEN SLOW
DOWN AS IT MOVES ACROSS LAKE SUPERIOR MONDAY AND MONDAY NIGHT.
THIS WILL BE A WINDY SYSTEM WITH STRONG SOUTH TO SOUTHWEST WINDS
SUNDAY NIGHT TURNING TO THE WEST AND EVENTUALLY NORTHWEST MONDAY
AND MONDAY NIGHT. SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED
OVER THE COASTAL WATERS WITH GUSTY WINDS...WITH GALE FORCE WINDS
AND HIGH WAVES POSSIBLE OVER THE OPEN WATERS.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...FROST ADVISORY FROM 1 AM TO 8 AM CDT SUNDAY FOR WIZ046-047-051-
     052-056>060-062>072.

LM...NONE.
&&

$$

UPDATE...SM/DDV
TODAY/TONIGHT AND AVIATION/MARINE...CRAVEN
SUNDAY THROUGH FRIDAY...WOOD









AREA FORECAST DISCUSSION

NWS MILWAUKEE/SULLIVAN WI

 326 AM CDT SAT OCT 19 2013

.TODAY...FORECAST CONFIDENCE IS HIGH.

FULL LATITUDE TROUGH PHASING JUST ABOUT OVERHEAD CURRENTLY WITH
110 METER 500 MB HEIGHT FALLS CENTERED OVER NORTHERN ILLINOIS
FIRST THING THIS MORNING. DEVELOPING BAROCLINIC LEAF AND SWATH OF
LIGHT PRECIPITATION SHOULD STAY TO THE SOUTH AND EAST.

CIRCULATION WITH DIGGING UPSTREAM TROUGH NOW ALONG MN/ND BORDER
HAS PV1.5 SURFACE POKING BELOW 500 MB AND THIS IS EXPECTED TO MOVE
INTO SOUTHEAST MINNESOTA THIS MORNING AND ACROSS SOUTHERN
WISCONSIN THIS AFTERNOON. EVEN THOUGH HEIGHTS STOP FALLING DURING
THE DAY THE 500 MB COLD CORE OF -30C MOVES ACROSS DURING PEAK
DIURNAL HEATING...WITH MODELS SHOWING STEEP LAPSE RATES IN THE LOW
LEVELS.

LATEST HRRR SHOWS BANDS OF CONVECTIVE SHOWERS MOVING ACROSS DURING
THE LATE MORNING AND AFTERNOON WHICH SEEMS REASONABLE. WOULD NOT
BE SURPRISED IF THERE IS GRAUPEL MIXED IN GIVEN THE LOW FREEZING
LEVEL WITH THE HEAVIER SHOWERS.

.TONIGHT...FORECAST CONFIDENCE IS HIGH.

HEIGHTS RISE ABOUT 90 METERS OVERNIGHT AND MODELS SHOW SIGNIFICANT
MID LEVEL DRYING DURING THE NIGHT. PROBABLY WILL NOT COMPLETELY
CLEAR OUT BUT BREAKS IN CLOUDS AND LIGHT WINDS FROM LATE EVENING
INTO THE 3-4 AM PERIOD SHOULD BE SUFFICIENT FOR READINGS TO DROP
TO AROUND FREEZING. MARGINAL NATURE OF EVENT SUGGESTS THAT A FROST
ADVISORY WOULD WORK BEST.

.SUNDAY THROUGH MONDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM TO
HIGH.

SHORT TERM MODELS IN DECENT AGREEMENT WITH FEATURES DURING THIS
PERIOD. SURFACE LOW PRESSURE TRACKS FROM SOUTHEASTERN NORTH DAKOTA
TO NORTHWEST WISCONSIN SUNDAY...THEN INTO NORTHERN LAKE SUPERIOR
SUNDAY NIGHT. FOCUSED WARM AIR ADVECTION SPREADS THROUGH THE
REGION AHEAD OF THE LOW ON SUNDAY...WITH A STRONG COLD FRONT
PUSHING EAST THROUGH THE AREA LATE SUNDAY/SUNDAY EVENING.

GOOD LOW LEVEL Q VECTOR CONVERGENCE ALSO SEEN SUNDAY ACROSS THE
AREA. AREA FORECAST SOUNDINGS SHOWING GOOD MID LEVEL MOISTURE
SUNDAY...WITH LOW LEVELS SLOWLY TRYING TO MOISTEN BY LATE IN THE
DAY AND EARLY SUNDAY EVENING. BEST UPWARD VERTICAL MOTION AND DEEP
MOISTURE IS TOWARD CENTRAL WISCONSIN...THOUGH QPF DOES PASS
THROUGH MOST OF THE AREA EXCEPT THE FAR SOUTH.

HAVE LIKELY POPS IN THE FAR NORTHWEST COUNTIES LATER SUNDAY
AFTERNOON...WITH HIGHER END CHANCE POPS SUNDAY INTO SUNDAY EVENING
ACROSS THE NORTHERN HALF OF THE AREA. LOW POPS WERE KEPT IN THE
SOUTH. TEMPERATURE PROFILES WILL BE WARM ENOUGH FOR ALL RAIN.

HIGHS IN THE 50S ARE EXPECTED SUNDAY...BEFORE COLD AIR ADVECTION
WITH BRISK WEST WINDS BEHIND COLD FRONT BRINGS COLDER AIRMASS INTO
THE REGION. LOWS SHOULD DROP INTO THE MID TO UPPER 30S SUNDAY
NIGHT. QUIET WEATHER BUT CHILLY DAY EXPECTED ON MONDAY...WITH
HIGHS ONLY IN THE 40S WITH BRISK WEST WINDS CONTINUING.

ADDED LOW POPS FOR LIGHT RAIN/SNOW SHOWERS IN THE FAR NORTH AND
NORTHEAST COUNTIES MONDAY NIGHT...WITH PASSING 500MB VORTICITY
MAXIMUM WITHIN LARGER CYCLONIC FLOW. GOOD SHOT AT FREEZE WARNING
CRITERIA FOR MONDAY NIGHT...AS LOWS SHOULD DROP INTO THE UPPER 20S
TO LOWER 30S ACROSS THE AREA...WITH DECREASING WEST WINDS. LATER
SHIFTS MAY CONSIDER A FREEZE WATCH FOR THE ENTIRE AREA FOR MONDAY
NIGHT.

.TUESDAY THROUGH FRIDAY...FORECAST CONFIDENCE IS MEDIUM.

ECMWF/GFS SHOWING SOME DIFFERENCES DURING THIS PERIOD. THEY SHOW
A GENERAL NORTHWEST FLOW AT 500MB CONTINUING THROUGH THE
WEEK...WITH SEVERAL VORTICITY MAXIMA SHIFTING THROUGH THE REGION.
THERE ARE TIMING DIFFERENCES WITH THESE FEATURES BETWEEN
ECMWF/GFS.

AT THE SURFACE...WEAK LOW PRESSURE PASSES WELL SOUTHWEST OF THE
AREA TUESDAY ON THE ECMWF/GFS. THEY BOTH THEN BRING HIGH PRESSURE
SOUTHEAST ACROSS THE CENTRAL PLAINS TUESDAY NIGHT. GFS THEN BRINGS
ANOTHER LOW SOUTHEAST THROUGH THE AREA LATER WEDNESDAY AND
WEDNESDAY EVENING...NOT SHOWN ON THE ECMWF.

BOTH MODELS THEN BRING HIGH PRESSURE SOUTHEAST THROUGH THE CENTRAL
PLAINS AGAIN THURSDAY INTO FRIDAY. THEY BOTH DO MAINTAIN THE COLD
AIRMASS OVER THE REGION. FOLLOWED CONSENSUS POPS AND TEMPERATURES
FOR THIS PERIOD. HIGHS SHOULD ONLY REACH THE 40S TUESDAY INTO
FRIDAY. LOWS SHOULD REMAIN IN THE UPPER 20S TO LOWER 30S
INLAND...WITH LOWER TO MID 30S LAKESIDE.

&&

.AVIATION/12Z TAFS/...

VFR MID LEVEL CLOUDS ARE EXPECTED MUCH OF THE TIME. UNSTABLE
CONDITIONS DURING THE LATE MORNING AND AFTERNOON WILL RESULT IN
CONVECTIVE SHOWERS WITH LOCALLY GUSTY WINDS...SMALL HAIL...AND
BRIEF MVFR CONDITIONS. THESE CONDITIONS WILL BE MOST LIKELY IN THE
KMSN AREA AND SOMEWHAT LESS LIKELY UNTIL LATE AFTERNOON IN THE
SOUTHEAST TAF SITES.

PARTIAL CLEARING IS EXPECTED TONIGHT WITH VFR CONDITIONS.

&&

.MARINE...

LAKE TO 850 MB TEMPERATURE DIFFERENCE INCREASES TO ABOUT 19 THIS
AFTERNOON AS COLD CORE MOVES ACROSS LAKE MICHIGAN. WESTERLY FLOW
REGIME SUGGESTS THAT WATERSPOUT THREAT SHOULD BE CONFINED MAINLY
TO CENTRAL AND EASTERN PORTION OF THE LAKE WHICH WOULD INCLUDE
EXTREME EASTERN PORTIONS OF THE OPEN WATERS.

FAST MOVING LOW ON SUNDAY WILL MOVE ACROSS WISCONSIN AND THEN SLOW
DOWN AS IT MOVES ACROSS LAKE SUPERIOR MONDAY AND MONDAY NIGHT.
THIS WILL BE A WINDY SYSTEM WITH STRONG SOUTH TO SOUTHWEST WINDS
SUNDAY NIGHT TURNING TO THE WEST AND EVENTUALLY NORTHWEST MONDAY
AND MONDAY NIGHT. SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED
OVER THE COASTAL WATERS WITH GUSTY WINDS...WITH GALE FORCE WINDS
AND HIGH WAVES POSSIBLE OVER THE OPEN WATERS.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...FROST ADVISORY FROM 1 AM TO 8 AM CDT SUNDAY FOR WIZ046-047-051-
     052-056>060-062>072.

LM...NONE.
&&

$$

TODAY/TONIGHT AND AVIATION/MARINE...CRAVEN
SUNDAY THROUGH FRIDAY...WOOD







AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 1105 PM CDT FRI OCT 18 2013

.UPDATE...
ISSUED AT 911 PM CDT FRI OCT 18 2013

THE CHANCES FOR PRECIPITATION TONIGHT INTO EARLY SATURDAY MORNING
ARE LOOKING LESS LIKELY NOW. THE FOCUS FOR PRECIPITATION TONIGHT
WAS ON A SHORTWAVE COMING ACROSS SOUTHWEST MINNESOTA. KMPX RADAR
SHOWS A BAND OF LIGHT RETURNS WHICH AT MOST HAVE PRODUCED
SPRINKLES AT REDWOOD FALLS IN THE PAST HOUR. OTHERWISE...THE BULK
OF THE RETURNS ARE VIRGA...DUE TO DRY LOW LEVEL AIR BELOW THE
7000-8000 FT CLOUD BASES AS SEEN ON THE 00Z MPX SOUNDING. RECENT
HRRR MODEL RUNS HAVE HAD A GOOD HANDLE ON THIS BAND OF LIGHT
PRECIPITATION...SUGGESTING IT WILL DIMINISH AS IT MOVES FURTHER
EAST INTO THE DRIER AIR. ADDITIONALLY...THE FORCING OVERALL FROM
THE SHORTWAVE JUST SEEMS TO BE WEAKENING. BELIEVE THIS IS DUE TO A
SOMEWHAT STRONGER SHORTWAVE DROPPING INTO EASTERN NORTH DAKOTA AS
SEEN ON WATER VAPOR. ADDITIONALLY...THIS SHORTWAVE HAS A 100-110
KT JET STREAK AT THE TROPOPAUSE ON ITS WESTERN SIDE PER RAP
ANALYSIS. THIS SHORTWAVE WILL BRING A MUCH GREATER CHANCE FOR
PRECIPITATION TO THE FORECAST AREA. TIMING OF THIS PRECIPITATION
HAS BECOME MORE PROBLEMATIC BY THE 18.23Z HRRR HAVING IT STILL
WEST OF I-35 AT 14Z...COMPARED TO THE 18.18Z NAM AND 18.15Z SREF
WHICH SUGGESTED IT ALREADY NEARING RST AT THE TIME.

FOR THE PRECIPITATION FORECAST...HAVE LOWERED CHANCES TO BASICALLY
DRY TONIGHT TO ABOUT 13-14Z SATURDAY MORNING. ONLY LEFT A 20
PERCENT CHANCE AROUND TAYLOR COUNTY PER 18.18Z NAM SUGGESTING
TAYLOR COUNTY COULD GET BRUSHED. CHANCES THEN RAMP UP WEST TO EAST
TO 60 BETWEEN THE 15-19Z PERIOD AS THE NEXT SHORTWAVE AND UPPER
JET STREAK FORCING IMPACTS THE AREA.

TEMPERATURES ARE AN ISSUE TONIGHT TOO. WHERE BREAKS HAVE DEVELOPED
IN THE CIRRUS OVER CENTRAL WISCONSIN...READINGS HAVE ALREADY
DROPPED TO NEAR/AROUND FREEZING. EVEN OVER SOUTHEAST MN DODGE
CENTER HAS FALLEN TO 35. HAVE LOWERED TEMPERATURES A FEW
DEGREES...BUT A STREAM OF BROKEN MID CLOUDS ACROSS MINNESOTA AND
NORTHWEST IOWA WILL MOVE THROUGH THE AREA OVERNIGHT. THESE CLOUDS
MAY CAUSE TEMPERATURES TO FLUCTUATE QUITE A BIT. ADDED AT LEAST
SOME PATCHY-AREAS OF FROST MENTION TO MUCH OF THE FORECAST
AREA RESULTING FROM THE LOWERING OF TEMPERATURES. CONFIDENCE IS
NOT HIGH ENOUGH TO ISSUE ANY FROST ADVISORIES IN OUR AREA THAT ARE
STILL ACTIVE / COUNTIES WEST OF I-94 / GIVEN CLOUD ISSUES.

&&

.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 333 PM CDT FRI OCT 18 2013

MAIN FORECAST CONCERN IS COLDER THAN NORMAL TEMPERATURES AND BOUTS
OF PRECIPITATION.

WATER VAPOR IMAGERY FEATURES A DEEP/ELONGATED LONGWAVE TROUGH OF LOW
PRESSURE EXTENDING FROM WESTERN HUDSONS BAY CANADA THROUGH THE UPPER
MISSISSIPPI RIVER AND INTO THE DESSERT SOUTHWEST. WITHIN THE LONGWAVE
TROUGH...A SHORTWAVE TROUGH WAS DROPPING SOUTHWARD OUT OF SOUTHERN
SASKATCHEWAN. VISIBLE SATELLITE SHOWING THE RESULT OF THE VERY
CHILLY AIR ALOFT WITH WIDESPREAD CUMULUS/STRATOCUMULUS ACROSS THE
DAKOTAS INTO MN/WESTERN WI. RADAR MOSAIC WAS EVEN SHOWING ISOLATED
SHOWERS ACTIVITY ACROSS NORTHEAST MN AND THE EASTERN DAKOTAS IN
ADVANCE OF THE SASKATCHEWAN WAVE. OTHERWISE...UNSEASONABLY COOL
AIRMASS IN PLACE ACROSS THE REGION WITH TEMPERATURES THIS AFTERNOON
STRUGGLING THROUGH THE 40S TO NEAR 50. THIS IS SOME 10-15 DEGREES BELOW
NORMAL.

FOR TONIGHT...THE WAVE OVER SASKATCHEWAN WILL DEEPEN SLIGHTLY AND
MOVE SOUTHEASTWARD INTO THE EASTERN DAKOTAS. NOT MUCH FORCING
ASSOCIATED WITH THIS WAVE OTHER THAN STEEPENING LAPSE RATES AND
SLIGHTLY INCREASED CYCLONIC FLOW. BASED ON THIS...WILL GO WITH
SMALL-END PRECIPITATION PROBABILITIES. IF SHOWERS DO DEVELOP...
THERMAL PROFILES SUPPORT MAINLY RAIN BUT CANNOT RULE OUT SOME SNOW
FLAKES NORTHEAST OF I-94. LOOK FOR OVERNIGHT LOWS IN THE MIDDLE TO
UPPER 30S.

AS THE TROUGH ROTATES OVER THE AREA SATURDAY...A STEEPENING LAPSE
RATE OF 8-10C/KM IN THE LOWEST 3KM AND CYCLONIC FLOW IS EXPECTED TO
GENERATE SCATTERED-NUMEROUS RAIN SHOWERS. OTHERWISE...PLAN ON HIGHS
IN THE 40S.

A FEW SHOWERS MAY LINGER INTO SATURDAY EVENING NORTHEAST OF
I-94...BUT THEN CLEARING IS EXPECTED LATER INTO THE EVENING AND
OVERNIGHT AS A WEAK RIDGE OF HIGH PRESSURE PASSES OVERHEAD. THIS
WILL SET UP GOOD RADIATIONAL COOLING WITH AREAS-WIDESPREAD FROST
LIKELY FOR MOST AREAS. OVERNIGHT LOWS ARE EXPECTED TO BOTTOM OUT IN
THE UPPER 20S NORTHEAST OF I-94...TO NEAR THE FREEZING MARK FOR ALL
OTHER LOCATIONS.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 333 PM CDT FRI OCT 18 2013

MODELS SHOWING A FAIRLY VIGOROUS MID-LEVEL TROUGH AND SURFACE LOW
DROPPING ACROSS THE DAKOTAS INTO SOUTHERN MN/WESTERN WI BY SUNDAY
AFTERNOON. MODELS SHOWING FAIRLY STRONG 850-500MB
PV-ADVECTION/ISENTROPIC LIFT ASSOCIATED WITH THIS WAVE. THIS HAS
BEEN A VERY CONSISTENT SIGNAL FOR THE LAST FEW DAYS OF MODEL RUNS
NOW. BASED ON THIS...WILL GO WITH LIKELY TO CATEGORICAL
PROBABILITIES ALONG AND NORTHEAST OF I-94...TAPERING TO CHANCES TO
THE SOUTH OF I-94. THERMAL PROFILES HINT THERE MAY BE A CHANCE THAT
AS THE PRECIPITATION MOVES IN SUNDAY MORNING...IT MAY FALL AS A
SNOW/RAIN MIX NORTH OF I-94. OTHERWISE WITH TEMPERATURES MODERATING
INTO THE 40S AND LOWER 50S DURING THE DAY...LOOK FOR THIS
PRECIPITATION TO BE ALL RAIN FROM MID-MORNING ONWARD THROUGH THE
REST OF THE DAY.

THIS LOW PULLS OFF INTO UPPER MICHIGAN SUNDAY EVENING...SPILLING
COLDER AIR INTO THE AREA. DEPENDING ON THE TIMING OF THIS COLD AIR
WITH THE TAPERING PRECIPITATION...THERE COULD BE A SLUSHY 1/4-1/2
INCH ACROSS NORTHERN PARTS OF TAYLOR COUNTY. THE PRECIPITATION IS
EXPECTED TO DIMINISH COMPLETELY AFTER MIDNIGHT AS THE LOW PULLS INTO
SOUTHERN ONTARIO. LOOK FOR OVERNIGHT LOWS IN THE 30-35 DEGREE RANGE.

ON MONDAY...MODELS SHOWING ANOTHER MID-LEVEL SHORTWAVE TROUGH
ROTATING SOUTHWARD AROUND THE NOW CLOSED/STACKED LOW OVER SOUTHERN
ONTARIO...INTO NORTHERN MN/WI. THE NAM IS SPREADS PRECIPITATION
FARTHEST SOUTH INTO THE AREA ASSOCIATED WITH THIS WAVE. MODEL
CONSENSUS YIELDS A 20-40 PERCENT PROBABILITY OF PRECIPITATION NORTH
OF I-94 WITH THE BULK OF THE PRECIPITATION STAYING NORTH OF THE
AREA. AGAIN...THERMAL PROFILES SHOW PRECIPITATION COULD BE ALL SNOW
IN THE MORNING...CHANGING TO ALL RAIN DURING THE REST OF THE DAY AS
HIGHS TO OFF IN THE UPPER 30S TO THE MIDDLE 40S.

THE EXTENDED MODELS CONTINUE TO SHOW A DEEP TROUGH ACROSS THE
EASTERN CONUS THROUGH THE REST OF THE PERIOD AS A RIDGE BUILDS OVER
THE WEST COAST. THIS KEEPS OUR AREA IN NORTHWEST FLOW ALOFT WITH
TEMPERATURES REMAINING SOME 10 DEGREES BELOW NORMAL WITH HIGHS ONLY
ON THE 40S. WITH MODELS HAVING A HARD TIME WITH STRENGTH AND
TIMING OF WEAKER WAVES RIPPLING THROUGH THIS NORTHWEST
FLOW...MODEL CONSENSUS IS FOR GENERALLY DRY STRETCH.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1105 PM CDT FRI OCT 18 2013

DRY AIR IN THE LOWER LEVELS OF THE ATMOSPHERE SHOULD HELP TO KEEP
CONDITIONS VFR THROUGH MUCH OF THE MORNING HOURS. THE MAIN CAVEAT
TO THIS IS POSSIBLE VALLEY FOG AT LSE...IF SKIES CAN REMAIN CLEAR
LONG ENOUGH FOR IT TO FORM. RIGHT NOW CONFIDENCE OF A CLEAR SKY
FOR THE REST OF THE NIGHT IS VERY LOW GIVEN MORE HIGH BASED
STRATUS COMING INTO SOUTHEAST MINNESOTA. THE MAIN IMPACT TO THE
TAF SITES DURING THE NEXT 24 HOURS IS A LOW PRESSURE TROUGH MOVING
THROUGH NORTH DAKOTA. THIS TROUGH SHOULD MOVE INTO THE TAF SITES
BETWEEN 16-19Z...PRODUCING SHOWERS AND LOWER CEILINGS. CEILINGS
SHOULD DROP TO MVFR AT RST AND VERY LOW VFR AT LSE. AFTER THE
TROUGH PASSES...BETWEEN 21-22Z...EXPECT VFR CONDITIONS TO RETURN
WITH SKIES CLEARING LATER IN THE EVENING AS DRIER AIR MOVES IN.
LOOK FOR WINDS TO BRIEFLY INCREASE TOO IN THE WAKE OF THE TROUGH
OUT OF THE WEST-NORTHWEST BETWEEN 10-15 KT.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&

$$

UPDATE...AJ
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...AJ








AREA FORECAST DISCUSSION

NWS GRAND JUNCTION CO

 1039 PM MDT SUN OCT 20 2013

.SHORT TERM...(TONIGHT THROUGH MONDAY NIGHT)
ISSUED AT 233 PM MDT SUN OCT 20 2013

IN NW FLOW ALOFT THE INITIAL VORTICITY MAXIMUM HAS PASSED TO THE
SE OF THE STEAMBOAT-VAIL LINE PRODUCING ENHANCEMENT EAST OF VAIL
PASS THIS EARLY AFTERNOON. SNOTELS SHOW 2 INCHES IN THE MTNS EAST
OF STEAMBOAT SPRINGS WITH HIGHER AMOUNTS IN THE PARK RANGE NEAR
THE WYOMING BORDER. SNOW ACCUMULATION LEVEL THIS AFTERNOON IS
AROUND 9KFT THERE. SOME LESS ORGANIZED ENERGY WILL ROLL OVER THE
ELKHEADS-PARK-GORE RANGES THIS AFTERNOON BUT THIS FORCING ENDS BY
SUNSET. LITTLE EXTRA ACCUMULATION IS EXPECTED EXCEPT PERHAPS IN
THE HIGHEST ELEVATIONS OF THE ZIRKEL WILDERNESS. THE 18Z RAP AND
HRRR END SHOWERS BY 6PM BUT THE NAM HOLDS ONTO SOME LIGHT
OROGRAPHIC SNOW ON NORTH-FACING SLOPES INTO THE EVENING. ALL AGREE
ITS ALL DONE BY MIDNIGHT. THEREFORE HAVE CUT BACK POPS FOR
TONIGHT.

SOME LOW-MID CLOUDS WILL LINGER OVERNIGHT MAINLY EAST OF A LINE
FROM CRAIG SOUTH TO MONARCH PASS. OTHERWISE PARTIALLY CLEARING
SKIES WILL KEEP TEMPERATURES BELOW NORMAL TONIGHT AND MONDAY.
WITH THE PASSING OF THESE FINAL DISTURBANCES THIS EVENING THE
WEST COAST RIDGE RELAXES INTO THE INTERMOUNTAIN WEST. BENIGN AND
DRY NW FLOW CONTINUES THROUGH MONDAY NIGHT AND BEYOND.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 233 PM MDT SUN OCT 20 2013

DRY WITH A GRADUAL WARMING TREND AS THE LARGE-SCALE PATTERN CHANGES
LITTLE. A BLOCKING UPPER RIDGE NEAR THE WEST COAST DRIFTS OVER THE
GREAT BASIN BY MIDWEEK BEFORE RETREATING BACK WESTWARD...WHILE A
LARGE TROUGH REMAINS OVER THE CENTRAL AND EASTERN PART OF THE
COUNTRY. NORTHWEST FLOW ON TUESDAY BECOMES WEST TO SOUTHWEST
WEDNESDAY-THURSDAY AS A WEAK WAVE UNDERCUTS THE RIDGE AND CROSSES
THE SOUTHERN GREAT BASIN...SWITCHING BACK TO NORTHWEST FRIDAY AS THE
WAVE PASSES BY TO OUR SOUTH. THIS WILL BRING SOME CLOUDS TO CENTRAL
AND SOUTHERN PARTS OF THE FORECAST AREA BUT LITTLE OR NO
PRECIPITATION...AND WILL KEEP THE FORECAST DRY. DAYTIME TEMPERATURES
WILL BE NEAR TO A LITTLE ABOVE NORMAL WHILE THE NIGHTS AVERAGE NEAR
NORMAL.

AN UPPER LOW IS EXPECTED TO PINCH OFF FROM THE NORTHERN JET
STREAM OVER THE NERN PACIFIC OCEAN AND GRADUALLY SETTLE OFF THE CA
COAST AND UNDERNEATH THE RIDGE BY LATE FRIDAY. MODELS OFTEN HAVE
DIFFICULTY HANDLING THESE CUT-OFF LOWS...AND THE GFS AND ECMWF
SHOW DIFFERENT SOLUTIONS BY NEXT MONDAY. BOTH INDICATE DRY WEATHER
STILL NEXT WEEKEND SO WILL CONTINUE WITH THAT FOR NOW...BUT
CONFIDENCE IS LOWERING BY SUNDAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1040 PM MDT SUN OCT 20 2013

MID LEVEL CLOUDS CONTINUE OVER THE NORTHERN AND CENTRAL MOUNTAINS
AT THIS HOUR WITH SOME -SN BEING REPORTED. NO TAF SITES REPORTING
CONDITIONS BELOW MVFR AND EXPECT THIS TO CONTINUE THROUGH THE
NIGHT AND WITH HIGH PRESSURE BUILDING IN TOMORROW...VFR WILL BE
COMMON ACROSS EASTERN UTAH AND WESTERN COLORADO.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...NONE.

UT...NONE.

&&

$$

SHORT TERM...JOE
LONG TERM...JAD
AVIATION...TGR







AREA FORECAST DISCUSSION

NWS MELBOURNE FL

 410 AM EDT MON OCT 21 2013

.DISCUSSION...

TODAY/TONIGHT...WEAK FRONT CURRENTLY ACROSS CENTRAL FLORIDA FROM
NORTH OF TAMPA TO THE CAPE IS STARTING TO SHOW SIGNS OF A SLOW
NORTHWARD MOVEMENT. THIS MOTION WILL LIKELY CONTINUE AND MAY REACH
JUST NORTH OF LAKE/VOLUSIA COUNTIES TODAY BEFORE STALLING OUT ONCE
AGAIN. WEAK LOW LEVEL WIND FIELD WILL PERSIST OVER THE REGION WITH
SEA BREEZE BOUNDARIES DEVELOPING AND MOVING INLAND. BEST CHANCE FOR
SHOWERS AND MAYBE EVEN A FEW STORMS WILL EXIST ACROSS THE INTERIOR
LATER THIS AFTERNOON WITH ANY BOUNDARY COLLISIONS OR INTERACTIONS
WITH THE FRONT. IF ANY STORMS DO DEVELOP A SOUTHWEST STEERING FLOW
WILL PUSH THIS CONVECTION BACK TOWARD THE COAST INTO THE EARLY
EVENING HOURS. HIGHS WILL RANGE FROM THE MID TO UPPER 80S WITH A FEW
LOCATIONS REACHING AROUND 90 DEGREES ACROSS INTERIOR LOCATIONS SOUTH
OF ORLANDO. OVERNIGHT LOWS WILL GENERALLY BE AROUND 70 DEGREES TO
LOW 70S.

TUE-FRI...ANTICYCLONIC FLOW AROUND WRN ATLC MID LEVEL RIDGE WILL
BECOME BROADLY CYCLONIC AS DEVELOPING ERN CONUS/WRN ATLC TROUGH
CAUSES H50 HEIGHT FALLS OF ABOUT 30-40M OVER THE FL PENINSULA.
THIS WILL FINALLY CAVE IN THE RESISTANCE TO THE COOL FRONT...
WHICH WILL GRADUALLY SAG INTO ON WEDNESDAY...PRECEDED BY INCRSG
CLOUDS/MOISTURE AND RAIN CHANCES FROM LATE TUE THRU WED. MODEST
STRIPE OF MID LEVEL VORTICITY COUPLED WITH RESPECTABLE UPPER DIVG
IN TAIL OF DEPARTING RR QUAD OF 120KT+ SERN CONUS JET STREAK WILL
PUSH OVHD..MAKING FOR A CLOUDY AND SOMEWHAT WET ~36 HR PERIOD...
FOLLOWED BY DRIER/COOLER WEATHER THU. RAIN CHCS WILL AVERAGE ABOUT
40-50 PCT FOR TUE THROUGH WED...WITH PRECIP ENDING N-S WED EVENING.
COOLER TEMPS WED DUE TO CLOUDS/PRECIP AND COOLER STILL ON THU OWING
TO MODIFIED CAA. REINFORCING SURFACE HIGH MOVES INTO THE SERN CONUS
FRI...WHICH WILL KEEP TEMPS FROM MODIFYING MUCH INTO THIS WEEKEND.

SAT-MON...E-W ORIENTED SFC RIDGE OVER THE SERN CONUS WEEKEND OVER
THE COURSE OF THIS WEEKEND WITH DRY CONDITIONS CONTINUING AND SLOWLY
MODIFYING TEMPS. ANOTHER SHORT WAVE TROUGH SLIDES THROUGH THE SERN
CONUS AND FL SUN NIGHT/EARLY MON BUT LOCAL AIR MASS APPEARS AS THOUGH
IT MAY BE TOO DRY TO SUPPORT PRECIP...IN SPITE OF DECENT MID LEVEL
LIFT. LARGE SURFACE HIGH BUILD OVER THE NERN CONUS WITH EASTERLY FLOW
STRENGTHENING OVER FL EARLY NEXT WEEK. TEMPS NEAR TO SLIGHTLY BELOW
NORMAL.

&&

.AVIATION...NOT LOOKING AS FAVORABLE FOR WIDESPREAD STRATUS/FOG
DEVELOPMENT THROUGH EARLY THIS MORNING...BUT SHOULD STILL SEE A FEW
LOCATIONS WHERE TEMPO IFR/MVFR CONDS OCCUR THROUGH 13Z. ISO/SCT
SHOWERS AND A FEW STORMS WILL BE POSSIBLE INTO THE AFTERNOON...
MAINLY OVER THE INTERIOR...BUT RAIN CHANCES REMAIN LOW ENOUGH TO
ONLY INCLUDE VCSH IN THE TAFS FOR NOW.

&&

.MARINE...

TODAY/TONIGHT...QUASI-STATIONARY FRONT WILL EXIST NEAR TO JUST NORTH
OF THE VOLUSIA COUNTY WATERS TODAY INTO TONIGHT. RELATIVELY LIGHT
AND VARIABLE WINDS THIS MORNING WILL BECOME ONSHORE AND THEN SWITCH
TO THE SOUTH TONIGHT. SEAS WILL RANGE FROM 2-3 FEET.

TUE-FRI...LIGHT OFFSHORE PRE-FRONTAL WINDS WILL INCREASE OUT OF THE
NORTH IMMEDIATELY BEHIND THE COLD FRONT WED AND NE WED NIGHT. WINDS
SLACKEN AND VEER A TAD ON THU BEFORE REINFORCING HIGH PRES AND ASCD
NE WIND SURGE PUSH SEAS BACK UP ON FRIDAY. CONDITIONS OVER THE GULF
STREAM WILL BE FAIRLY CHOPPY...ESPECIALLY WED AND FRI..GIVEN THE
PREVAILING N-NE WIND FLOW.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  84  70  82  68 /  20  20  50  50
MCO  88  71  86  70 /  30  20  40  50
MLB  87  72  85  71 /  20  20  40  50
VRB  88  72  88  70 /  20  20  40  40
LEE  88  71  85  68 /  30  20  40  50
SFB  87  71  86  69 /  30  20  50  50
ORL  88  72  86  70 /  30  20  40  50
FPR  88  71  87  70 /  20  20  40  40

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&

$$

SHORT TERM/AVIATION...WEITLICH
LONG TERM/IMPACT WX....CRISTALDI










AREA FORECAST DISCUSSION

NWS MELBOURNE FL

 355 AM EDT MON OCT 21 2013

.DISCUSSION...

TODAY/TONIGHT...WEAK FRONT CURRENTLY ACROSS CENTRAL FLORIDA FROM
NORTH OF TAMPA TO THE CAPE IS STARTING TO SHOW SIGNS OF A SLOW
NORTHWARD MOVEMENT. THIS MOTION WILL LIKELY CONTINUE AND MAY REACH
JUST NORTH OF LAKE/VOLUSIA COUNTIES TODAY BEFORE STALLING OUT ONCE
AGAIN. WEAK LOW LEVEL WIND FIELD WILL PERSIST OVER THE REGION WITH
SEA BREEZE BOUNDARIES DEVELOPING AND MOVING INLAND. BEST CHANCE FOR
SHOWERS AND MAYBE EVEN A FEW STORMS WILL EXIST ACROSS THE INTERIOR
LATER THIS AFTERNOON WITH ANY BOUNDARY COLLISIONS OR INTERACTIONS
WITH THE FRONT. IF ANY STORMS DO DEVELOP A NORTHWEST STEERING FLOW
WILL PUSH THIS CONVECTION BACK TOWARD THE COAST INTO THE EARLY
EVENING HOURS. HIGHS WILL RANGE FROM THE MID TO UPPER 80S WITH A FEW
LOCATIONS REACHING AROUND 90 DEGREES ACROSS INTERIOR LOCATIONS SOUTH
OF ORLANDO. OVERNIGHT LOWS WILL GENERALLY BE AROUND 70 DEGREES TO
LOW 70S.

TUE-FRI...ANTICYCLONIC FLOW AROUND WRN ATLC MID LEVEL RIDGE WILL
BECOME BROADLY CYCLONIC AS DEVELOPING ERN CONUS/WRN ATLC TROUGH
CAUSES H50 HEIGHT FALLS OF ABOUT 30-40M OVER THE FL PENINSULA.
THIS WILL FINALLY CAVE IN THE RESISTANCE TO THE COOL FRONT...
WHICH WILL GRADUALLY SAG INTO ON WEDNESDAY...PRECEDED BY INCRSG
CLOUDS/MOISTURE AND RAIN CHANCES FROM LATE TUE THRU WED. MODEST
STRIPE OF MID LEVEL VORTICITY COUPLED WITH RESPECTABLE UPPER DIVG
IN TAIL OF DEPARTING RR QUAD OF 120KT+ SERN CONUS JET STREAK WILL
PUSH OVHD..MAKING FOR A CLOUDY AND SOMEWHAT WET ~36 HR PERIOD...
FOLLOWED BY DRIER/COOLER WEATHER THU. RAIN CHCS WILL AVERAGE ABOUT
40-50 PCT FOR TUE THROUGH WED...WITH PRECIP ENDING N-S WED EVENING.
COOLER TEMPS WED DUE TO CLOUDS/PRECIP AND COOLER STILL ON THU OWING
TO MODIFIED CAA. REINFORCING SURFACE HIGH MOVES INTO THE SERN CONUS
FRI...WHICH WILL KEEP TEMPS FROM MODIFYING MUCH INTO THIS WEEKEND.

SAT-MON...E-W ORIENTED SFC RIDGE OVER THE SERN CONUS WEEKEND OVER
THE COURSE OF THIS WEEKEND WITH DRY CONDITIONS CONTINUING AND SLOWLY
MODIFYING TEMPS. ANOTHER SHORT WAVE TROUGH SLIDES THROUGH THE SERN
CONUS AND FL SUN NIGHT/EARLY MON BUT LOCAL AIR MASS APPEARS AS THOUGH
IT MAY BE TOO DRY TO SUPPORT PRECIP...IN SPITE OF DECENT MID LEVEL
LIFT. LARGE SURFACE HIGH BUILD OVER THE NERN CONUS WITH EASTERLY FLOW
STRENGTHENING OVER FL EARLY NEXT WEEK. TEMPS NEAR TO SLIGHTLY BELOW
NORMAL.

&&

.AVIATION...NOT LOOKING AS FAVORABLE FOR WIDESPREAD STRATUS/FOG
DEVELOPMENT THROUGH EARLY THIS MORNING...BUT SHOULD STILL SEE A FEW
LOCATIONS WHERE TEMPO IFR/MVFR CONDS OCCUR THROUGH 13Z. ISO/SCT
SHOWERS AND A FEW STORMS WILL BE POSSIBLE INTO THE AFTERNOON...
MAINLY OVER THE INTERIOR...BUT RAIN CHANCES REMAIN LOW ENOUGH TO
ONLY INCLUDE VCSH IN THE TAFS FOR NOW.

&&

.MARINE...

TODAY/TONIGHT...QUASI-STATIONARY FRONT WILL EXIST NEAR TO JUST NORTH
OF THE VOLUSIA COUNTY WATERS TODAY INTO TONIGHT. RELATIVELY LIGHT
AND VARIABLE WINDS THIS MORNING WILL BECOME ONSHORE AND THEN SWITCH
TO THE SOUTH TONIGHT. SEAS WILL RANGE FROM 2-3 FEET.

TUE-FRI...LIGHT OFFSHORE PRE-FRONTAL WINDS WILL INCREASE OUT OF THE
NORTH IMMEDIATELY BEHIND THE COLD FRONT WED AND NE WED NIGHT. WINDS
SLACKEN AND VEER A TAD ON THU BEFORE REINFORCING HIGH PRES AND ASCD
NE WIND SURGE PUSH SEAS BACK UP ON FRIDAY. CONDITIONS OVER THE GULF
STREAM WILL BE FAIRLY CHOPPY...ESPECIALLY WED AND FRI..GIVEN THE
PREVAILING N-NE WIND FLOW.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  84  70  82  68 /  20  20  50  50
MCO  88  71  86  70 /  30  20  40  50
MLB  87  72  85  71 /  20  20  40  50
VRB  88  72  88  70 /  20  20  40  40
LEE  88  71  85  68 /  30  20  40  50
SFB  87  71  86  69 /  30  20  50  50
ORL  88  72  86  70 /  30  20  40  50
FPR  88  71  87  70 /  20  20  40  40

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&

$$

SHORT TERM/AVIATION...WEITLICH
LONG TERM/IMPACT WX....CRISTALDI






AREA FORECAST DISCUSSION

NWS TALLAHASSEE FL

 257 AM EDT Mon Oct 21 2013

.NEAR TERM [Today]...
Based on objective RUC analysis early this morning, there exists a
considerable theta-e gradient in the 900-700mb layer roughly from
buoy 42039, to TLH, to VLD. The air mass to the southeast of this
boundary is fairly moist, with mixing ratios in the same layer about
+1 to +2 standard deviations above normal. The combination of the
low-level theta-e gradient bisecting our forecast area, and the
anomalously moist air mass over the southeast half of the area
should provide enough impetus for isolated showers today along and
southeast of the aforementioned line. This is supported by CAM
guidance, with a variety of hi-res models showing a similar
scenario. The 03-04z runs of the HRRR even show some slow-moving
thunderstorms near Apalachicola that produce over 1 inch of rain.
That may not be the most likely scenario, but we did shift some of
the 20-30% PoPs that had previously only been over the water into
some of the coastal counties. Most areas should see at least some
filtered sunshine today, with the result being highs near normal.

&&

.SHORT TERM [Tonight Through Wednesday]...
While we see decent agreement among the various models in their
handling of large scale upper levels features over the next 48
hours, there remain differences in the surface response which will
have an impact on the PoP forecast, mainly for Tuesday and Tuesday
night. The NAM and GFS continue to be drier than the 12 UTC Euro,
although the GFS has trended wetter. The Euro appears to have a
better handle on the short wave over northern Mexico and we
therefore favor its more enhanced QPF forecast. We continue to use a
blend of guidance for the sensible weather, but are mixing in a much
larger percentage of the ECMWF solution. This brings slight chance
PoPs to the area late tonight. Highest PoPs will be on Tuesday and
we have raised them to likely across our FL Big Bend and adjacent
zones, tapering off to the northwest. Chance PoPs will then linger
into Tuesday night with precip ending from northwest to southeast
early Wednesday morning as the latest in a series of progressively
stronger cold fronts pushes through. This front will coolest airmass
of the season to the region (see below).

&&

.LONG TERM [Wednesday Night through Sunday]...
The upper level synoptic pattern will continue to stay in place
during the long term period. High pressure ridging will sit over the
west coast while a trough hangs over the eastern CONUS. The trough
will de-amplify early in the period as a wave of energy ejects to the
northeast, but will likely deepen again towards the end of the
period, as another wave of energy swings through the trough. With a
cool, dry air mass in place, rain chances will be low through the
period (less than 20%) and temperatures will be noticeably cooler
with highs in the upper 60s to mid 70s and lows in the 40s to around
50.

&&

.AVIATION...
[Through 06 UTC Tuesday] Much of the TAF period will be dominated
by VFR ceilings at all terminals. However, there could be some
MVFR CIGS at TLH and VLD near a region of greater low-level
moisture around sunrise. This would be most likely after 09 UTC,
and prior to 15 UTC.


&&

.MARINE...
Winds and seas will remain relatively low over the marine area until
a strong cold front crosses the waters Wednesday morning. Offshore
winds behind this front will increase to cautionary or marginal
advisory levels from early Wednesday into midday Thursday. Moderate
northwest flow will then persist into Friday.

&&

.FIRE WEATHER...
RH will remain relatively high for the next couple days before a
reinforcing cold front arrives. Much drier air is expected for the
latter half of the week, from Wednesday to Friday at least. Despite
the drier air, the current forecast would probably make red flag
conditions unlikely. However, there could be an increased fire
danger by late in the week.

&&

.HYDROLOGY...
Despite chances for showers and isolated thunderstorms through
Tuesday night, rainfall amounts are not expected to be high enough
to cause significant rises on area rivers or any other flooding
concerns.

&&

.PRELIMINARY POINT TEMPS/POPS...
Tallahassee   82  64  80  58  78 / 10  20  60  40  10
Panama City   80  65  81  60  79 / 10  20  50  30  10
Dothan        77  57  81  51  74 / 10  20  40  20   0
Albany        78  60  81  52  76 / 10  20  40  20   0
Valdosta      79  62  78  58  76 / 10  20  60  40  10
Cross City    84  67  79  63  79 / 20  20  60  40  20
Apalachicola  81  66  79  62  78 / 20  20  60  40  10

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.

&&

$$

Near Term/Aviation/Fire Weather...Lamers
Long Term...Moore
Rest of Discussion...Wool





AREA FORECAST DISCUSSION

NWS MARQUETTE MI

 538 AM EDT MON OCT 21 2013

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 537 AM EDT MON OCT 21 2013

WV IMAGERY AND RUC ANALYSIS INDICATED A RIDGE INTO THE PACIFIC NW
AND A BROAD MID/UPPER LEVEL TROUGH ACROSS THE CNTRL AND EAST CONUS.
A MID LEVEL LOW WAS LOCATED NEAR KINL. A SHORTWAVE TROUGH THAT
BROUGHT THE AREA OF RAIN/SNOW THROUGH UPPER MI WAS LIFTING TO THE
ENE THROUGH CNTRL UPPER MI. AT THE SFC...LOW PRES WAS LOCATED NEAR
WHITE FISH BAY. A TROUGH EXTENDED TO THE NW THROUGH CNTRL LAKE
SUPERIOR AND INTO SRN MANITOBA. RADAR INDICATED THAT THE MAIN AREA
OF PCPN HAD MOVED INTO ERN LAKE SUPERIOR WITH MAINLY
FLURRIES/DRIZZLE TO THE WEST AS 850-500 QVECTOR DIV MOVES IN BEHIND
THE SHRTWV.

TODAY...CONVERGENT LOW LEVEL WRLY WINDS ACROSS LAKE SUPERIOR WITH
850 MB TEMPS FALLING FROM -5C TO -8C AND ABUNDANT MOISTURE BELOW 700
MB SHOULD CONTINUE TO SUPPORT SCT/NMRS SNOW SHOWERS INTO NW UPPER MI
THAT WILL BE MIXED WITH RAIN NEAR THE SHORELINE. THE HIGH RES MODELS
SUGGEST THAT THE SNOW SHOWERS WILL BE MOST PROMINENT IN THE AREA
FROM NEAR ONTONAGON AND ROCKLAND TO TWIN LAKES AND PELKIE.
OTHERWISE...MAINLY DRY WEATHER IS EXPECTED ACROSS THE REST OF THE
CWA WITH SYNOPTIC SCALE SUBSIDENCE TAKING OVER. IT WILL ALSO FEEL
COLDER WITH GUSTY WEST WINDS AND HIGHS FROM THE MID AND UPPER 30S
WEST TO THE MID 40S EAST.

TONIGHT...EXPECT THE SNOW SHOWERS OVER THE WEST TO INCREASE IN
COVERAGE AND INTENSITY AS THE SFC TROUGH EDGES INTO THE AREA. THE
ENHANCED LOW LEVEL CONV WITH THIS FEATURE COMBINED WITH 850 MB TEMPS
AROUND -7C AND THE PROXIMITY OF THE MID LEVEL LOW WILL LEAD TO LAKE
INDUCED CAPE VALUES TO AROUND 500 J/KG. A PERIOD OF MODERATE TO
HEAVY SNOW SHOULD SPREAD INTO NW UPPER MI THIS EVENING AND SAG INTO
IWD BY LATE EVENING AND INTO MARQUETTE COUNTY AFT 06Z. A TRANSITION
TO WIND PARALLEL NNW FLOW LAKE ENHANCED SNOW IS THEN EXPECTED
FOLLOWING PASSAGE OF THE TROUGH. OVERALL SNOW TOTALS IN THE 1 TO 4
INCH RANGE ARE EXPECTED WITH THE GREATEST AMOUNTS IN THE HIGHER
TERRAIN FROM TWIN LAKE SOUTHWARD AND OVER THE HURON MOUNTAINS.
SNOW/WATER RATIOS SHOULD REMAIN RELATIVELY LOW...AOB 10/1...AS THE
STRONGEST UPWARD MOTION REMAINS BELOW THE DGZ AND THE LOWER LEVELS
REMAIN NEAR 0C. AN ADVISORY WAS POSTED FOR THE WRN HALF OF THE CWA
ADJOINING LAKE SUPERIOR.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 350 AM EDT MON OCT 21 2013

A LARGE UPPER TROUGH WILL BE OVER THE GREAT LAKES REGION FOR THIS
WORK WEEK AND LEAD TO BELOW NORMAL TEMPERATURES FOR UPPER MICHIGAN.
THIS COLD AIR WILL ALSO LEAD TO LAKE EFFECT SNOW NEAR LAKE
SUPERIOR. UNCERTAINTY GROWS HEADING INTO THE WEEKEND ON HOW THE
MODELS HANDLE THE UPPER TROUGH SHIFTING EAST OR RE-AMPLIFYING OVER
THE GREAT LAKES.

FOR TUESDAY...THE SURFACE TROUGH THAT WILL BE SWEEPING EAST ACROSS
UPPER MICHIGAN TONIGHT WILL QUICKLY EXIT EASTERN UPPER MICHIGAN ON
TUESDAY MORNING. PRECIPITATION WILL BE ONGOING OVER MUCH OF UPPER
MICHIGAN...ESPECIALLY NEAR LAKE SUPERIOR WITH THE NORTHWEST LAKE
ENHANCED FLOW. MODELS ARE CONTINUING TO SHOW MOISTURE ABOVE 850MB
TO QUICKLY DIMINISH FROM NORTHWEST TO SOUTHEAST ACROSS THE AREA
THROUGH THE DAY ON TUESDAY. THINK THIS DRY AIR ENTRAINMENT WILL
REALLY PUT A CRIMP ON THE SNOWFALL OVER MUCH OF THE CWA EVEN WITH
THE DELTA-T VALUES AROUND 18 AND OVER LAKE INSTABILITY IS AROUND
300-500 J/KG. THUS...WILL SHOW THE HIGHEST POPS TO START TUESDAY AND
QUICKLY DIMINISH VALUES THROUGH THE AFTERNOON HOURS. HELD ON TO THE
HIGHEST POPS OVER THE EAST SINCE THERE MAY BE ENOUGH TIME OVER THE
LAKE TO KEEP SOME SHOWERS AROUND THROUGH THE DAY. EVEN THOUGH THE
DEEPER MOISTURE IS LACKING...WILL SHOW MOSTLY CLOUDY SKIES FOR
THE NORTHWEST WIND FAVORED LOCATIONS INTO THE AFTERNOON.

A WEAK SHORTWAVE SLIDING THROUGH THE AREA ON TUESDAY EVENING WILL
BRING INCREASING LOW LEVEL MOISTURE ACROSS THE LAKE TUESDAY NIGHT
AND THAT WILL CONTINUE INTO WEDNESDAY. 850MB TEMPS ARE STILL AROUND
-7C TUESDAY NIGHT INTO WEDNESDAY...SO THERE IS PLENTY OF OVER THE
LAKE INSTABILITY TO SUPPORT LAKE EFFECT SNOWFALL IN THE NORTHWEST
WIND FAVORED LOCATIONS. EQUILIBRIUM LEVELS AROUND 12KFT WILL
SUPPORT DEEP CLOUD DEPTHS FOR MODERATE LAKE EFFECT SNOW POTENTIAL.
SNOWFALL AMOUNTS WILL LIKELY BE LIMITED BY SNOW RATIOS BEING
AROUND 10-1 DUE TO ONLY THE TOP 5KFT OF THE CLOUD WITHIN THE DGZ AND
THE BEST LAKE FORCING BELOW THAT. THEREFORE...SHOULD SEE SOME
CLUMPING OF THE FLAKES TO SUPPORT THE MORE SYSTEM SNOW LIKE SLR
VALUES...WHICH WILL CUT SNOWFALL AMOUNTS IN HALF FROM WHAT IS
TRADITIONALLY SEEN DURING PURE LES EVENTS. IN ADDITION...WITH
DAYTIME TEMPERATURES TRYING TO RISE INTO THE UPPER 30S OVER THE
EAST...IT TRENDS AWAY FROM THE LOWER 30S GENERALLY NEEDED FOR SNOW
ACCUMULATION. THAT FACTOR IS ALSO INFLUENCED BY THE NORTHWEST WINDS
COMING OFF LAKE SUPERIOR WITH IT/S SURFACE TEMPS AROUND 50
DEGREES...WHICH DOES RAISE THE WETBULB VALUES TO HAVE SOME RAIN
MIXING IN DURING THE DAY WEDNESDAY. THINKING THE BEST OPPORTUNITY
FOR MEASUREABLE SNOW WOULD BE UNDER THE HEAVIEST BANDS AND LATE
TUESDAY NIGHT AND INTO WEDNESDAY MORNING. THEREFORE...HAVE MOST NW
WIND LOCATIONS ONLY SEEING AROUND AN INCH OF SNOW THROUGH WEDNESDAY.
AS WE GET A LITTLE CLOSER WE SHOULD BE ABLE TO PIN DOWN ANY STRONGER
BANDS...WHICH WOULD LOWER TEMPS AND INCREASE SNOWFALL ACCUMULATIONS.

SINCE THE AREA WILL CONTINUE TO BE BETWEEN THE LOW JUST EAST OF
JAMES BAY AND A SERIES OF HIGHS SLIDING SOUTHEAST THROUGH THE
NORTHERN PLAINS...EXPECT THE NORTHWEST WINDS TO CONTINUE THROUGH
THURSDAY NIGHT. 850MB TEMPS LOOK LIKE THERE IS LITTLE VARIABILITY
DURING THAT PERIOD AND WITH MODELS CONTINUING TO SHOW ENOUGH
MOISTURE IN THE LOWER LEVELS...WILL HIGHLIGHT LIKELY POPS IN THE
NORMAL NORTHWEST WIND LOCATIONS THROUGH THE TIME PERIOD. ALTHOUGH
ACCUMULATIONS WON/T BE LARGE...STILL THINK THERE WILL BE SOME AREAS
IN THE WEST AND EAST OF MUNISING THAT WILL HAVE A FEW INCHES OF
SNOW ON THE GROUND BY FRIDAY. BEST OPPORTUNITY FOR ACCUMULATIONS
WILL BE OVER THE WEST...WITH THE EXISTING SNOW ON THE GROUND FROM
TONIGHT.

MODELS REALLY DIFFER ON THE HANDLING OF A SHORTWAVE DIVING
SOUTHEAST TOWARDS THE GREAT LAKES REGION ON FRIDAY AND ACROSS THE
AREA ON SATURDAY OR SUNDAY. THIS SHORTWAVE HAS A LONG JOURNEY AHEAD
OF IT (CURRENTLY NORTH OF HAWAII) AND NEEDS TO ROUND THE RIDGE OVER
THE WEST AND POTENTIALLY MERGE WITH THE ANOTHER WAVE IN NORTHWEST
CANADA. WITH THAT LONG OF A DISTANCE TO TRAVEL...IT/S NOT
SURPRISING THAT THERE ARE DIFFERENCES IN THE GEM/ECMWF/GFS ON THE
SHORTWAVE AND POTENTIAL CLIPPER SYSTEM MOVING THROUGH THE AREA.
12Z GEM/GFS WERE FAIRLY SIMILAR ON THE WAVE AND CLIPPER MOVING
THROUGH ON FRIDAY NIGHT INTO SATURDAY MORNING...WHILE THE 12Z ECMWF
WAS MUCH SLOWER AND KEEPS THE CLIPPER NORTH OF THE AREA (MOVING
THROUGH NORTHERN ONTARIO ON SATURDAY NIGHT). 00Z RUNS HAVE
FLIPPED THE GEM/ECMWF IDEAS WITH THE 00Z GFS STAYING SIMILAR. THESE
DIFFERENCES LEAD TO LITTLE OR NO CONFIDENCE FOR THAT TIME FRAME
OTHER THAN THE BELOW NORMAL HIGH TEMPERATURES WILL CONTINUE.
USING A GENERAL CONSENSUS OF THE MODELS GIVES LOW END CHANCE POPS
FOR THE WEEKEND.
&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 127 AM EDT MON OCT 21 2013

EXPECT IFR CIGS TO PREDOMINATE THIS MRNG AT IWD WHILE CONDITIONS
DETERIORATE TO IFR AT CMX WITH WSHFT TO AN UPSLOPE WNW COMPONENT
ASSOCIATED WITH SFC LO SHIFTING NEWD INTO ERN LK SUP. IFR CONDITIONS
MAY OCCUR AT SAW AS WELL. ONCE THE DEEPENING LO MOVES INTO LK SUP
LATER THIS MRNG...W WINDS WL TURN QUITE GUSTY...ESPECIALLY AT THE
MORE EXPOSED CMX LOCATION. WITH THE ARRIVAL OF SOMEWHAT DRIER LLVL
AIR...PLAN ON A SLOW IMPROVEMENT TO MVFR DESPITE PERSISTENT UPSLOPE
WIND COMPONENT. SAW SHOULD SEE VFR CIGS IN DOWNSLOPE FLOW. ARRIVAL
OF ANOTHER LO PRES TROF THIS EVNG WL BRING IFR CONDITIONS/SOME SHSN
AT IWD/CMX.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 401 PM EDT SUN OCT 20 2013

A LOW CENTERED OVER MUCH OF MINNESOTA AN NORTHERN IOWA WILL SLIDE
ACROSS THE UPPER GREAT LAKES TONIGHT THROUGH EARLY MONDAY. EXPECT
THIS LOW TO LIFT SLOWLY INTO QUEBEC MONDAY AFTERNOON WHILE KEEPING A
TROUGH OVER THE UPPER GREAT LAKES THROUGH THURSDAY. A PERIOD OF 35KT
GUSTS WILL BE POSSIBLE OVER S LAKE SUPERIOR STARTING MID MORNING
MONDAY /OUT OF THE W/. A SECOND PUSH OF STRONGER WINDS WILL COME IN
AS THE TROUGH OF LOW PRESSURE WRAPS BACK AROUND...WITH A PERIOD OF
NW GALES OF 35 TO NEAR 40KTS OVER MAINLY CENTRAL AND E LAKE SUPERIOR
MONDAY NIGHT INTO MID TUESDAY. WINDS WILL SLOWLY DIMINISH TUESDAY
AFTERNOON...WITH GUSTS LINGERING IN THE 20 TO 30KT RANGE THROUGH THE
REST OF THE WORK WEEK.

BROAD HIGH PRESSURE OF IS EXPECTED TO BUILD OVER MUCH OF THE PLAINS
STATES BY THURSDAY NIGHT AND SPREAD EASTWARD INTO MUCH OF EASTERN
CONTINENTAL UNITED STATES...WITH A RIDGE OVER THE UPPER GREAT LAKES.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
  WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 8 AM EDT
     TUESDAY FOR MIZ002>004-084.

  WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO 7 AM CDT
     TUESDAY FOR MIZ009.

  WINTER WEATHER ADVISORY FROM 1 AM TO 11 AM EDT TUESDAY FOR
     MIZ005.

LAKE SUPERIOR...
  GALE WARNING FROM 11 AM THIS MORNING TO 11 AM EDT TUESDAY FOR
     LSZ265>267.

  GALE WARNING FROM 8 PM THIS EVENING TO 11 AM EDT TUESDAY FOR
     LSZ264.

  GALE WARNING FROM 11 AM THIS MORNING TO 8 AM EDT TUESDAY FOR
     LSZ263.

LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...JLB
LONG TERM...SRF
AVIATION...KC
MARINE...KF







AREA FORECAST DISCUSSION

NWS GRAND FORKS ND

 1131 PM CDT SUN OCT 20 2013

.UPDATE...
ISSUED AT 1130 PM CDT SUN OCT 20 2013

NO CHANGES NECESSARY THIS UPDATE PERIOD.

UPDATE ISSUED AT 936 PM CDT SUN OCT 20 2013

CLEARING CONTINUES TO EXPAND ACROSS SOUTHERN MB AND LOOKS TO BE
ENTERING FAR NORTHERN FA. WITH CURRENT TEMPERATURES AS THEY ARE EVEN
WITH MODEST MIXING ANY CLEARING SHOULD BE ABLE TO QUICKLY DROP
TEMPERATURES TO EXPECTED MINIMUMS SO FOR NOW WILL HOLD WITH
FORECAST MINS. UNTIL CLOUDS DECREASE ADDED FLURRIES WITH WEAK
RETURNS FROM KMVX-88D. MADE MORE ADJUSTMENTS TO CLOUD TRENDS WITH
REMAINDER OF FORECAST OK.

UPDATE ISSUED AT 641 PM CDT SUN OCT 20 2013

BIG CHALLENGE TONIGHT WILL BE MINIMUM TEMPERATURES WHICH WILL
HINGE ON CLOUD TRENDS. SOME BREAKS SHOWING UP IN SOUTHERN MB
HOWEVER STILL PRETTY SOLID CLOUD COVER ACROSS THE FA. WILL BE
MONITORING CLOUD TRENDS THROUGH THE EVENING. AT THIS POINT NOT
PLANNING ANY CHANGES OTHER THAN ADJUSTING CLOUD COVER A BIT.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 316 PM CDT SUN OCT 20 2013

CHALLENGES THROUGH THE PERIOD INCLUDE LOW END PRECIPITATION CHANCES
AND TEMPERATURES. GFS/NAM/ECMWF/GEM IN REASONABLE AGREEMENT AND
WILL FOLLOW AND BLENDED MODEL SOLUTION.

20 UTC SURFACE ANALYSIS SHOWS THE SURFACE LOW SOUTHWEST OF
MINNEAPOLIS AND MOST OF ITS ASSOCIATED PRECIPITATION ACROSS THE MN
ARROWHEAD INTO NORTHWEST WI. A COUPLE SURFACE OBS ACROSS WEST
CENTRAL MN STILL REPORTING LIGHT RAIN...BUT WITH VISIBILITY OF 10
SM...MOST LIKELY JUST SOME LINGERING SPRINKLES. WILL CONTINUE THIS
DRYING TREND INTO THE EARLY EVENING WITH ONLY SOME 20 POPS ACROSS
THE LAKE OF THE WOODS REGION OVERNIGHT AS THE SURFACE LOW PIVOTS
BACK TO THE NORTH AND ITS INVERTED TROUGH PINWHEELS ABOUT THE
INTERNATIONAL BORDER.

THERE IS ABUNDANT CLOUD COVER UPSTREAM...BUT IT IS MORE CELLULAR
IN NATURE...SO IT/S DIFFICULT TO SAY HOW MUCH CLEARING WILL OCCUR
OVERNIGHT...ESPECIALLY WHEN THE RAP 925 HPA RH SHOWS SATURATED
CONDITIONS THROUGH MONDAY MORNING. WILL SHOW SOME CLEARING WEST OF
THE VALLEY BY 12 UTC MONDAY...BUT THIS MAY BE OVERLY OPTIMISTIC.
EITHER WAY...WITH HIGHS THIS AFTERNOON IN THE 30S...NIGHTTIME
LOWS IN THE 20S SEEM REASONABLE.

BEST CHANCE FOR PRECIPITATION MONDAY WILL CONTINUE ACROSS THE LAKE
OF THE WOODS REGION WITH ALL OTHER AREAS DRY. SHOULD SEE A BIT
MORE SUN TO THE SOUTH AND WEST...BUT COLD AIR MASS WILL KEEP
HIGH TEMPERATURES IN THE 30S. NORTH-NORTHWEST WIND WILL PERSIST...
BUT WITH A WEAKENING PRESSURE GRADIENT...SHOULD BE A BIT LOWER
FROM 10 TO 15 MPH.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 316 PM CDT SUN OCT 20 2013

CANADIAN HIGH PRESSURE DIVES SOUTH ACROSS THE NORTHERN PLAINS
TUESDAY AND WEDNESDAY FOR MOSTLY DRY CONDITIONS. HOWEVER...
PERSISTENT CYCLONIC FLOW ALOFT COMBINED WITH HIGHER MID-LEVEL
MOISTURE WILL RESULT IN QUITE A BIT OF CLOUDS. MID-LEVEL THERMAL
RIDGE WILL NUDGE EASTWARD...ALLOWING FOR A LITTLE WARMING EACH
DAY...SO THAT HIGHS BY WEDNESDAY SHOULD APPROACH 40 DEGREES. THIS
IS STILL 10 TO 15 DEGREES BELOW MID-LATE OCTOBER NORMALS.

WED NIGHT-SUNDAY...NORTHWEST FLOW ALOFT THOUGH THE PERIOD. 12Z
MODELS ARE IN GOOD AGREEMENT INITIALLY...BUT QUICKLY DISAGREE WITH A
STRONGER WAVE FRIDAY INTO SUNDAY. THE GFS/GEM ARE MUCH QUICKER AND
FURTHER WEST WITH THIS WAVE THAN THE ECMWF. THE GFS/GEM BRING PRECIP
INTO NORTHWEST MINNESOTA WITH THIS FEATURE...WHILE THE ECMWF IS
BASICALLY DRY THROUGH THE PERIOD. TEMPERATURES WOULD ALSO BE
AFFECTED WITH EXACTLY WHERE THIS WAVE TRACKS. THE BLEND OF MODELS IS
LIKELY THE BEST COURSE OF ACTION.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1130 PM CDT SUN OCT 20 2013

WILL SEE VFR CONDITIONS THROUGH THE FORECAST PERIOD.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

UPDATE...VOELKER
SHORT TERM...ROGERS
LONG TERM...ROGERS/TG
AVIATION...VOELKER







AREA FORECAST DISCUSSION

NWS TULSA OK

 1148 PM CDT SUN OCT 20 2013

.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
A FEW AREAS OF SHOWERS NOTED ACROSS WESTERN OK LATE THIS
EVENING. THIS ACTIVITY SHOULD EXPAND EASTWARD OVERNIGHT
AND COULD IMPACT THE KTUL/KRVS AND KMLC TAF SITES AROUND
10Z...AND EVENTUALLY MOVE INTO WESTERN AR AFTER 12-13Z.
CIGS SHOULD REMAIN GENERALLY AROUND 5KFT.

&&

.PREV DISCUSSION... /ISSUED 932 PM CDT SUN OCT 20 2013/

DISCUSSION...
CLOUDINESS WILL BE ON THE INCREASE OVERNIGHT AS AN UPPER LEVEL
DISTURBANCE APPROACHES THE AREA FROM THE WEST AND A COLD FRONT
MOVES INTO NORTHEAST OKLAHOMA FROM THE NORTH. THERE IS A STRONG
SIGNAL IN RECENT RUNS OF THE HRRR THAT CONFIRMS THE 12Z ECMWF AND
UKMET SIGNALS THAT PRECIPITATION WILL BREAK OUT ACROSS PARTS OF
CENTRAL AND EASTERN OKLAHOMA OVERNIGHT. AS SUCH...WILL ADD POPS TO
AREAS SOUTHEAST OF INTERSTATE 44 LATER TONIGHT. WILL ALSO MAKE
SOME MINOR TEMPERATURES CHANGES.

UPDATE COMING SHORTLY.

&&

.PRELIMINARY POINT TEMPS/POPS...
TUL   46  56  39  71 /  20  50  10   0
FSM   46  61  39  70 /  10  50  30   0
MLC   46  60  37  72 /  50  50  10   0
BVO   44  55  35  69 /  10  20  10   0
FYV   42  56  33  65 /  10  50  20  10
BYV   44  56  35  64 /  10  40  20  10
MKO   44  57  37  69 /  40  50  10   0
MIO   44  56  36  67 /  10  20  10  10
F10   46  55  38  71 /  30  50  10   0
HHW   46  68  42  71 /  20  50  30   0

&&

.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&

$$

SHORT TERM...99
LONG TERM....99
AVIATION...18






AREA FORECAST DISCUSSION

NWS HOUSTON/GALVESTON TX

 442 AM CDT MON OCT 21 2013

.DISCUSSION...
BASED ON 00Z UPPER AIR ANALYSIS AND WATER VAPOR IMAGERY...FIRST
OF A COUPLE OF SHORT WAVE TROUGHS IS AFFECTING SE TX THIS MORNING.
UPWARD VERTICAL MOTION FROM THE FIRST SHORTWAVE IS SUPPORTING
CONVECTION BETWEEN VICTORIA AND WHARTON THIS MORNING ON RADAR
IMAGERY. ALSO GETTING QUITE A BIT OF CONVECTION TO DEVELOP OFF THE
LOWER TX COAST AND S TX. SECOND MORE SIGNIFICANT TROUGH AXIS IS
BACK OVER THE S ROCKIES AND SHOULD BE PUSHING THROUGH LATER TODAY
AND TONIGHT AS IT SHEARS OUT. JET STEAM IS ALSO EXPECTED TO BECOME
MORE FAVORABLE FOR UPWARD MOTION AS IT STRENGTHENS OVER THE MID
SOUTH AND POSITIONS DIVERGENCE OVER SE TX FROM RIGHT ENTRANCE
REGION OF THE JET. EXPECT THERE TO BE SOME ISENTROPIC LIFT AS WELL
FROM DISSIPATING FRONTAL BOUNDARY IN THE GULF. ALL OF THIS SHOULD
SUPPORT SOME RAINFALL ACROSS THE SOUTHERN PORTION OF SE TX AND
ALONG THE COAST. THE 06Z HRRR AND 00Z TX TECH WRF KEEP MOST OF THE
PRECIP OFF THE COAST AND HAVE ORIENTED POPS AS SUCH. POPS MAY BE
ABOUT 10 PERCENT TOO HIGH ACROSS THE BOARD FOR INLAND AREAS BUT
THINK THAT MOST AREAS WILL SEE AT LEAST SOME RAIN...JUST LOWER
AMOUNTS. LOOKS LIKE THE COASTAL COUNTIES WILL LIKELY HAVE MAYBE
0.25-0.5 INCHES OF RAIN. AN 1 INCH TOTALS WILL BE OUT IN THE GULF.
THE REST OF SE TX LIKELY HAVE A TENTH OF AN INCH IF THAT. DESPITE
CLOUD COVER STILL THINK MAX TEMPS IN THE UPPER 70S LOOK GOOD WITH
MOISTURE AND WARM ADVECTION IN PLACE TODAY.

COLD FRONT CURRENTLY WORKING THROUGH OKLA AND W TX WILL PUSH INTO
SE TX TONIGHT AND OFF THE COAST BY 12Z TUE. THIS SHOULD END ANY
RAIN CHANCES FOR SE TX WITH THE BULK OF THE PRECIP IN THE GULF
HEADED TOWARDS N GULF COAST. COLD ADVECTION DURING THE DAY SHOULD
KEEP MAX TEMPS IN THE MID 70S ALONG THE COAST AND LOW 70S FARTHER
INLAND. HIGH PRESSURE WILL BUILD OVER SE TX FOR WED MORNING SO
EXPECT MIN TEMPS BACK IN THE UPPER 40S TO LOW 50S.

NEAR TO BELOW NORMAL TEMPERATURES ARE LIKELY TO CONTINUE THE REST
OF THE WEEK. UPPER LEVEL PATTERN SHOULD BE QUITE AMPLIFIED WITH
LONG WAVE TROUGH OVER THE GREAT LAKES AND NW FLOW ACROSS THE
PLAINS DUE TO RIDGING OVER THE WEST COAST. SHORT WAVE TROUGH STILL
EXPECTED TO IMPACT N TX THROUGH SE TX ON SATURDAY BUT LOOKS MUCH
WEAKER. MOISTURE WILL ALSO BE LIMITED SO BACKED OFF ON POPS SOME
BUT KEPT A PERIOD OF 20 POPS FOR NORTHERN AREAS OF SE TX WHERE
LIFT MAY BE MAXIMIZED. OTHERWISE FORECAST SHOULD BE DRY THROUGH
THE WEEKEND. TEMPERATURES WERE NOT ADJUSTED VERY MUCH BUT DID
TREND TEMPS COOLER FOR THE WEEKEND. ANOTHER AREA OF HIGH PRESSURE
WILL BUILD OVER THE MISS RIVER VALLEY WITH NE/E BOUNDARY LAYER
FLOW OVER SE TX. THIS SHOULD ALLOW FOR COOLER AIR TO FILTER INTO
THE REGION FOR THE WEEKEND. THIS WILL LIKELY KEEP TEMPS NEAR
NORMAL OR EVEN A DEGREE OR TWO BELOW NORMAL.

39

&&

.MARINE...
ONSHORE FLOW THIS MORNING WILL PERSIST THROUGH THE DAY AHEAD OF A
COLD FRONT WHICH WILL PUSH OFFSHORE JUST BEFORE DAYBREAK ON
TUESDAY. CAUTION FLAGS WILL BE NEEDED IN THE WAKE OF THE FRONT
WITH ADVISORY CONDITIONS POSSIBLE FOR A BRIEF PERIOD ON TUESDAY.
EXPECT BRISK NORTH AND NORTHEAST WINDS THROUGH THE END OF THE WEEK
WITH CAUTION FLAGS POSSIBLE FOR MOST OF THE WEEK. 38

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      78  54  73  51  77 /  30  20  10  10  10
HOUSTON (IAH)              79  58  75  52  78 /  50  20  10  10  10
GALVESTON (GLS)            79  67  77  62  77 /  50  40  10  10  10

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&

$$

DISCUSSION...39
AVIATION/MARINE...38





AREA FORECAST DISCUSSION

NWS MARQUETTE MI

 742 AM EDT MON OCT 21 2013

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 537 AM EDT MON OCT 21 2013

WV IMAGERY AND RUC ANALYSIS INDICATED A RIDGE INTO THE PACIFIC NW
AND A BROAD MID/UPPER LEVEL TROUGH ACROSS THE CNTRL AND EAST CONUS.
A MID LEVEL LOW WAS LOCATED NEAR KINL. A SHORTWAVE TROUGH THAT
BROUGHT THE AREA OF RAIN/SNOW THROUGH UPPER MI WAS LIFTING TO THE
ENE THROUGH CNTRL UPPER MI. AT THE SFC...LOW PRES WAS LOCATED NEAR
WHITE FISH BAY. A TROUGH EXTENDED TO THE NW THROUGH CNTRL LAKE
SUPERIOR AND INTO SRN MANITOBA. RADAR INDICATED THAT THE MAIN AREA
OF PCPN HAD MOVED INTO ERN LAKE SUPERIOR WITH MAINLY
FLURRIES/DRIZZLE TO THE WEST AS 850-500 QVECTOR DIV MOVES IN BEHIND
THE SHRTWV.

TODAY...CONVERGENT LOW LEVEL WRLY WINDS ACROSS LAKE SUPERIOR WITH
850 MB TEMPS FALLING FROM -5C TO -8C AND ABUNDANT MOISTURE BELOW 700
MB SHOULD CONTINUE TO SUPPORT SCT/NMRS SNOW SHOWERS INTO NW UPPER MI
THAT WILL BE MIXED WITH RAIN NEAR THE SHORELINE. THE HIGH RES MODELS
SUGGEST THAT THE SNOW SHOWERS WILL BE MOST PROMINENT IN THE AREA
FROM NEAR ONTONAGON AND ROCKLAND TO TWIN LAKES AND PELKIE.
OTHERWISE...MAINLY DRY WEATHER IS EXPECTED ACROSS THE REST OF THE
CWA WITH SYNOPTIC SCALE SUBSIDENCE TAKING OVER. IT WILL ALSO FEEL
COLDER WITH GUSTY WEST WINDS AND HIGHS FROM THE MID AND UPPER 30S
WEST TO THE MID 40S EAST.

TONIGHT...EXPECT THE SNOW SHOWERS OVER THE WEST TO INCREASE IN
COVERAGE AND INTENSITY AS THE SFC TROUGH EDGES INTO THE AREA. THE
ENHANCED LOW LEVEL CONV WITH THIS FEATURE COMBINED WITH 850 MB TEMPS
AROUND -7C AND THE PROXIMITY OF THE MID LEVEL LOW WILL LEAD TO LAKE
INDUCED CAPE VALUES TO AROUND 500 J/KG. A PERIOD OF MODERATE TO
HEAVY SNOW SHOULD SPREAD INTO NW UPPER MI THIS EVENING AND SAG INTO
IWD BY LATE EVENING AND INTO MARQUETTE COUNTY AFT 06Z. A TRANSITION
TO WIND PARALLEL NNW FLOW LAKE ENHANCED SNOW IS THEN EXPECTED
FOLLOWING PASSAGE OF THE TROUGH. OVERALL SNOW TOTALS IN THE 1 TO 4
INCH RANGE ARE EXPECTED WITH THE GREATEST AMOUNTS IN THE HIGHER
TERRAIN FROM TWIN LAKE SOUTHWARD AND OVER THE HURON MOUNTAINS.
SNOW/WATER RATIOS SHOULD REMAIN RELATIVELY LOW...AOB 10/1...AS THE
STRONGEST UPWARD MOTION REMAINS BELOW THE DGZ AND THE LOWER LEVELS
REMAIN NEAR 0C. AN ADVISORY WAS POSTED FOR THE WRN HALF OF THE CWA
ADJOINING LAKE SUPERIOR.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 350 AM EDT MON OCT 21 2013

A LARGE UPPER TROUGH WILL BE OVER THE GREAT LAKES REGION FOR THIS
WORK WEEK AND LEAD TO BELOW NORMAL TEMPERATURES FOR UPPER MICHIGAN.
THIS COLD AIR WILL ALSO LEAD TO LAKE EFFECT SNOW NEAR LAKE
SUPERIOR. UNCERTAINTY GROWS HEADING INTO THE WEEKEND ON HOW THE
MODELS HANDLE THE UPPER TROUGH SHIFTING EAST OR RE-AMPLIFYING OVER
THE GREAT LAKES.

FOR TUESDAY...THE SURFACE TROUGH THAT WILL BE SWEEPING EAST ACROSS
UPPER MICHIGAN TONIGHT WILL QUICKLY EXIT EASTERN UPPER MICHIGAN ON
TUESDAY MORNING. PRECIPITATION WILL BE ONGOING OVER MUCH OF UPPER
MICHIGAN...ESPECIALLY NEAR LAKE SUPERIOR WITH THE NORTHWEST LAKE
ENHANCED FLOW. MODELS ARE CONTINUING TO SHOW MOISTURE ABOVE 850MB
TO QUICKLY DIMINISH FROM NORTHWEST TO SOUTHEAST ACROSS THE AREA
THROUGH THE DAY ON TUESDAY. THINK THIS DRY AIR ENTRAINMENT WILL
REALLY PUT A CRIMP ON THE SNOWFALL OVER MUCH OF THE CWA EVEN WITH
THE DELTA-T VALUES AROUND 18 AND OVER LAKE INSTABILITY IS AROUND
300-500 J/KG. THUS...WILL SHOW THE HIGHEST POPS TO START TUESDAY AND
QUICKLY DIMINISH VALUES THROUGH THE AFTERNOON HOURS. HELD ON TO THE
HIGHEST POPS OVER THE EAST SINCE THERE MAY BE ENOUGH TIME OVER THE
LAKE TO KEEP SOME SHOWERS AROUND THROUGH THE DAY. EVEN THOUGH THE
DEEPER MOISTURE IS LACKING...WILL SHOW MOSTLY CLOUDY SKIES FOR
THE NORTHWEST WIND FAVORED LOCATIONS INTO THE AFTERNOON.

A WEAK SHORTWAVE SLIDING THROUGH THE AREA ON TUESDAY EVENING WILL
BRING INCREASING LOW LEVEL MOISTURE ACROSS THE LAKE TUESDAY NIGHT
AND THAT WILL CONTINUE INTO WEDNESDAY. 850MB TEMPS ARE STILL AROUND
-7C TUESDAY NIGHT INTO WEDNESDAY...SO THERE IS PLENTY OF OVER THE
LAKE INSTABILITY TO SUPPORT LAKE EFFECT SNOWFALL IN THE NORTHWEST
WIND FAVORED LOCATIONS. EQUILIBRIUM LEVELS AROUND 12KFT WILL
SUPPORT DEEP CLOUD DEPTHS FOR MODERATE LAKE EFFECT SNOW POTENTIAL.
SNOWFALL AMOUNTS WILL LIKELY BE LIMITED BY SNOW RATIOS BEING
AROUND 10-1 DUE TO ONLY THE TOP 5KFT OF THE CLOUD WITHIN THE DGZ AND
THE BEST LAKE FORCING BELOW THAT. THEREFORE...SHOULD SEE SOME
CLUMPING OF THE FLAKES TO SUPPORT THE MORE SYSTEM SNOW LIKE SLR
VALUES...WHICH WILL CUT SNOWFALL AMOUNTS IN HALF FROM WHAT IS
TRADITIONALLY SEEN DURING PURE LES EVENTS. IN ADDITION...WITH
DAYTIME TEMPERATURES TRYING TO RISE INTO THE UPPER 30S OVER THE
EAST...IT TRENDS AWAY FROM THE LOWER 30S GENERALLY NEEDED FOR SNOW
ACCUMULATION. THAT FACTOR IS ALSO INFLUENCED BY THE NORTHWEST WINDS
COMING OFF LAKE SUPERIOR WITH IT/S SURFACE TEMPS AROUND 50
DEGREES...WHICH DOES RAISE THE WETBULB VALUES TO HAVE SOME RAIN
MIXING IN DURING THE DAY WEDNESDAY. THINKING THE BEST OPPORTUNITY
FOR MEASUREABLE SNOW WOULD BE UNDER THE HEAVIEST BANDS AND LATE
TUESDAY NIGHT AND INTO WEDNESDAY MORNING. THEREFORE...HAVE MOST NW
WIND LOCATIONS ONLY SEEING AROUND AN INCH OF SNOW THROUGH WEDNESDAY.
AS WE GET A LITTLE CLOSER WE SHOULD BE ABLE TO PIN DOWN ANY STRONGER
BANDS...WHICH WOULD LOWER TEMPS AND INCREASE SNOWFALL ACCUMULATIONS.

SINCE THE AREA WILL CONTINUE TO BE BETWEEN THE LOW JUST EAST OF
JAMES BAY AND A SERIES OF HIGHS SLIDING SOUTHEAST THROUGH THE
NORTHERN PLAINS...EXPECT THE NORTHWEST WINDS TO CONTINUE THROUGH
THURSDAY NIGHT. 850MB TEMPS LOOK LIKE THERE IS LITTLE VARIABILITY
DURING THAT PERIOD AND WITH MODELS CONTINUING TO SHOW ENOUGH
MOISTURE IN THE LOWER LEVELS...WILL HIGHLIGHT LIKELY POPS IN THE
NORMAL NORTHWEST WIND LOCATIONS THROUGH THE TIME PERIOD. ALTHOUGH
ACCUMULATIONS WON/T BE LARGE...STILL THINK THERE WILL BE SOME AREAS
IN THE WEST AND EAST OF MUNISING THAT WILL HAVE A FEW INCHES OF
SNOW ON THE GROUND BY FRIDAY. BEST OPPORTUNITY FOR ACCUMULATIONS
WILL BE OVER THE WEST...WITH THE EXISTING SNOW ON THE GROUND FROM
TONIGHT.

MODELS REALLY DIFFER ON THE HANDLING OF A SHORTWAVE DIVING
SOUTHEAST TOWARDS THE GREAT LAKES REGION ON FRIDAY AND ACROSS THE
AREA ON SATURDAY OR SUNDAY. THIS SHORTWAVE HAS A LONG JOURNEY AHEAD
OF IT (CURRENTLY NORTH OF HAWAII) AND NEEDS TO ROUND THE RIDGE OVER
THE WEST AND POTENTIALLY MERGE WITH THE ANOTHER WAVE IN NORTHWEST
CANADA. WITH THAT LONG OF A DISTANCE TO TRAVEL...IT/S NOT
SURPRISING THAT THERE ARE DIFFERENCES IN THE GEM/ECMWF/GFS ON THE
SHORTWAVE AND POTENTIAL CLIPPER SYSTEM MOVING THROUGH THE AREA.
12Z GEM/GFS WERE FAIRLY SIMILAR ON THE WAVE AND CLIPPER MOVING
THROUGH ON FRIDAY NIGHT INTO SATURDAY MORNING...WHILE THE 12Z ECMWF
WAS MUCH SLOWER AND KEEPS THE CLIPPER NORTH OF THE AREA (MOVING
THROUGH NORTHERN ONTARIO ON SATURDAY NIGHT). 00Z RUNS HAVE
FLIPPED THE GEM/ECMWF IDEAS WITH THE 00Z GFS STAYING SIMILAR. THESE
DIFFERENCES LEAD TO LITTLE OR NO CONFIDENCE FOR THAT TIME FRAME
OTHER THAN THE BELOW NORMAL HIGH TEMPERATURES WILL CONTINUE.
USING A GENERAL CONSENSUS OF THE MODELS GIVES LOW END CHANCE POPS
FOR THE WEEKEND.
&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 741 AM EDT MON OCT 21 2013

WITH A DEEPENING LOW INTO ERN LAKE SUEPRIOR...W WINDS WILL BECOME QUITE
GUSTY...ESPECIALLY AT THE MORE EXPOSED CMX LOCATION. WITH THE ARRIVAL
OF SOMEWHAT DRIER LOW LEVEL AIR...PLAN ON A SLOW IMPROVEMENT TO MVFR
DESPITE A PERSISTENT UPSLOPE WIND COMPONENT. SAW SHOULD SEE VFR CIGS
IN DOWNSLOPE FLOW. ARRIVAL OF ANOTHER LO PRES TROF THIS EVENING WILL
BRING IFR CONDITIONS/SHSN AT IWD/CMX WHICH WILL GRADUALLY DIMINISH
LATE TONIGHT.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 401 PM EDT SUN OCT 20 2013

A LOW CENTERED OVER MUCH OF MINNESOTA AN NORTHERN IOWA WILL SLIDE
ACROSS THE UPPER GREAT LAKES TONIGHT THROUGH EARLY MONDAY. EXPECT
THIS LOW TO LIFT SLOWLY INTO QUEBEC MONDAY AFTERNOON WHILE KEEPING A
TROUGH OVER THE UPPER GREAT LAKES THROUGH THURSDAY. A PERIOD OF 35KT
GUSTS WILL BE POSSIBLE OVER S LAKE SUPERIOR STARTING MID MORNING
MONDAY /OUT OF THE W/. A SECOND PUSH OF STRONGER WINDS WILL COME IN
AS THE TROUGH OF LOW PRESSURE WRAPS BACK AROUND...WITH A PERIOD OF
NW GALES OF 35 TO NEAR 40KTS OVER MAINLY CENTRAL AND E LAKE SUPERIOR
MONDAY NIGHT INTO MID TUESDAY. WINDS WILL SLOWLY DIMINISH TUESDAY
AFTERNOON...WITH GUSTS LINGERING IN THE 20 TO 30KT RANGE THROUGH THE
REST OF THE WORK WEEK.

BROAD HIGH PRESSURE OF IS EXPECTED TO BUILD OVER MUCH OF THE PLAINS
STATES BY THURSDAY NIGHT AND SPREAD EASTWARD INTO MUCH OF EASTERN
CONTINENTAL UNITED STATES...WITH A RIDGE OVER THE UPPER GREAT LAKES.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
  WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 8 AM EDT
     TUESDAY FOR MIZ002>004-084.

  WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO 7 AM CDT
     TUESDAY FOR MIZ009.

  WINTER WEATHER ADVISORY FROM 1 AM TO 11 AM EDT TUESDAY FOR
     MIZ005.

LAKE SUPERIOR...
  GALE WARNING FROM 11 AM THIS MORNING TO 11 AM EDT TUESDAY FOR
     LSZ265>267.

  GALE WARNING FROM 8 PM THIS EVENING TO 11 AM EDT TUESDAY FOR
     LSZ264.

  GALE WARNING FROM 11 AM THIS MORNING TO 8 AM EDT TUESDAY FOR
     LSZ263.

LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...JLB
LONG TERM...SRF
AVIATION...JLB
MARINE...KF







AREA FORECAST DISCUSSION

NWS PORTLAND OR

 445 AM PDT MON OCT 21 2013

.SYNOPSIS...A STRONG UPPER LEVEL RIDGE ALONG THE COAST CONTINUES TO
DOMINATE THE WEATHER ACROSS THE WESTERN UNITED STATES AND CANADA...
PUSHING THE MAIN PACIFIC STORM TRACK WELL NORTH INTO ALASKA. THIS
WILL MAINTAIN DRY WEATHER WITH MILD DAYS AND COOL NIGHTS IN SOUTHWEST
WASHINGTON AND NORTHWEST OREGON...ALONG WITH AREAS OF DENSE NIGHT AND
MORNING FOG. A BIT OF EAST WIND SHOULD DEVELOP IN THE GORGE
AND SPREAD INTO THE PORTLAND AND VANCOUVER METRO AREA MONDAY NIGHT...
LEADING TO LESS FOG IN THESE AREAS TUESDAY MORNING. AFTER SOME
POSSIBLE COASTAL DRIZZLE WEDNESDAY THE FORECAST LOOKS DRY.

&&

.UPDATE...UPDATE ON THE FOG FOR THE METRO AREA THIS MORNING. A SOLID
STRATUS DECK IS HOLDING AT ABOUT 200 FEET. SO WHILE THE LOWEST
ELEVATIONS MAY NOT BE SEEING DENSE FOG WHERE MANY OF OUR OBSERVATION
STATIONS ARE LOCATED...ANY CHANGING TERRAIN ABOVE 200 FEET
INTERSECTING THE FOG WILL EASILY ENCOUNTER WIDELY VARYING VISIBILITY
AND ENTER THE DENSE FOG. CAUTION IS STILL URGED FOR THE MORNING
COMMUTE.

.SHORT TERM...MONDAY THROUGH WEDNESDAY...
THINGS ARE PROGRESSING IN A SOMEWHAT SIMILAR FASHION TO LAST
NIGHT...WITH THE MINOR EXCEPTION THAT WE ARE STARTING TO DEVELOP AN
OFFSHORE GRADIENT THROUGH THE COLUMBIA RIVER GORGE AND ALONG THE
EAST SIDE OF THE WARNING AREAS. INVERSIONS ARE IN PLACE TO KEEP THE
EAST WIND FROM SURFACING OUTSIDE OF THE GORGE JUST YET. THAT MEANS
FAIRLY LIGHT WINDS TO EVEN A LIGHT NORTHWEST WIND AROUND PORTLAND
THAT IS JOINING WITH RADIATIONAL PROCESSES TO BRING LOW CLOUDS AND
FOG IN FROM THE NORTH WHERE IT HAS BEEN LOCKED IN PLACE FOR THE PAST
FEW DAYS. THE COWLITZ RIVER VALLEY AND KELSO/LONGVIEW AREAS ARE
AGAIN SEEING LOW STRATUS RATHER THAN DENSE FOG...AS THE COLD POOL
STRATUS OVER THE PUGET SOUND PUSHES INTO THE AREA BEFORE FOG CAN
DEVELOP. MEANWHILE AT THE COAST...FOG IS DENSE FROM ABOUT LINCOLN
CITY SOUTHWARD...WHILE EAST WINDS ARE SHOWING UP NEAR ASTORIA KEEPING
THINGS AT BAY. STILL THINK RADIATIONAL PROCESSES WILL ALLOW FOR SOME
FOG HERE TOO.

WE DO HAVE WIDELY VARYING VISIBILITIES...BUT LATEST HRRR GUIDANCE FOR
SFC VISIBILITY WHICH HAD A DECENT HANDLE ON THE DENSE FOG YESTERDAY
SUGGESTS IT REMAINS A CONCERN THROUGH THE VALID TIME OF THE CURRENT
ADVISORY. HAVE SOME CONCERNS THAT WITH THE WINDS ABOVE THE SURFACE
BEING A BIT STRONGER TODAY WITH THE OFFSHORE GRADIENT THAT THE FOG
WILL ONLY REMAIN DENSE IN WIND SHELTERED LOCATIONS AND THAT IT WILL
LIFT TO A LOW STRATUS DECK AS IS NOW TAKING PLACE IN SEVERAL
LOCATIONS.  WILL HANG ONTO THE VALLEY ADVISORY FOR NOW AND MONITOR
THE TRENDS AS WE STILL HAVE PLENTY OF SPOTS AT THREE QUARTERS OF A
MILE VISIBILITY OR LESS AND QUARTER MILE VISIBILITY AT HILLSBORO AND
MCMINNVILLE. ELEVATED LOCATIONS MAY BE IN THE LOW CLOUD AND THUS IN
THE FOG ANYWAYS AND CAMERAS ON I-205 DO SHOW SOME PRETTY DENSE FOG
AS OF 300 AM. MEANWHILE...THE HRRR ALSO SUGGESTS THE CENTRAL COAST
WILL HANG ONTO DENSE FOG AND ON THE NORTH COAST FROM TILLAMOOK
SOUTH. FEEL THESE AREAS WILL KEEP LIGHT WINDS UNDER THE COASTAL LOW
TO WARRANT ADDITION OF THE CENTRAL COAST INTO THE ADVISORY...AND
WILL ADD THE NORTH COAST TOO DESPITE IT BEING FOCUSED ON THE
SOUTHERN HALF OF THE ZONE.  AREAS NORTH TOWARD ASTORIA AND INTO THE
SOUTH WASHINGTON COAST ARE FEELING THE EAST WIND A BIT MORE AS SEEN
IN THE MSLP ANALYSIS. ALL LOWLAND AREAS MAY ALSO EXPERIENCE SOME
DRIZZLY MIST OUT OF THE LOW CLOUDS WHEN HEADING OUT THIS MORNING.

THE COLD POOL DEEPENS LATER THIS MORNING...WHICH ALLOWS HIGH PRESSURE
TO STRENGTHEN ENOUGH EAST OF THE CASCADES TO PUSH THE EASTERLY
PRESSURE GRADIENTS INTO THE PORTLAND METRO AREA. MONDAY NIGHT/EARLY
TUESDAY APPEARS TO BE THE TIME PERIOD WHERE FOG WILL HAVE A HARD
TIME RE-FORMING AROUND THE PDX METRO DUE TO MODERATE EASTERLY GORGE
WINDS. THERE MAY BE ENOUGH OFFSHORE COMPONENT TO KEEP THE NORTH
COAST CLEAR MON NIGHT AS WELL. AS A RESULT THESE AREAS SHOULD BE A
FEW DEGREES WARMER ON TUESDAY. EXPECT TEMPERATURES TODAY TO BE
SOMEWHAT ON PAR WITH YESTERDAY...THOUGH GUIDANCE SUGGESTS A SMALL
INCREASE ESPECIALLY FOR LOCATIONS WHERE LOW CLOUDS AND FOG LINGER
THE LEAST. /KMD

REST OF THE SHORT TERM DISCUSSION UNCHANGED...EASTERLY WINDS SHOULD
CONTINUE THROUGH THE GORGE AND ACROSS THE
PORTLAND/VANCOUVER METRO TUE NIGHT/EARLY WED...BUT SHOULD BEGIN TO
EASE AS HIGH PRESSURE WEAKENS EAST OF THE CASCADES. HOWEVER...AT THE
SAME TIME A WEAK UPPER LEVEL CUTOFF LOW WILL BE MEANDERING CLOSER TO
THE OREGON COAST. THIS MAY KEEP FLOW EASTERLY ACROSS THE NORTHERN
HALF OF OUR FORECAST AREA...WHILE DEEPENING THE MARINE LAYER AND
INDUCING A SOUTHERLY WIND REVERSAL ALONG THE CENTRAL OREGON COAST.
THE DEEPENING MARINE LAYER MAY BE ENOUGH TO WRING OUT SOME COASTAL
DRIZZLE AND COULD EVENTUALLY SPREAD COASTAL LOW CLOUDS INTO THE
WILLAMETTE VALLEY.  WEAGLE

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...WEDNESDAY
NIGHT THROUGH SUNDAY...THE WEAK DRY LOW CIRCULATION OFF THE OREGON
COAST AT THE END OF THE SHORT TERM PERIOD WILL DRIFT NORTH TOWARD
B.C. DURING THE FIRST PART OF THE LANG TERM PERIOD...REPLACED BY A
LARGER LOW OFF THE CALIFORNIA COAST. WE LOOK TO STAY DRY...THOUGH WE
WILL HAVE A BIT MORE PERSISTENT LOW LEVEL MARINE LAYER NEAR THE
COAST...WITH MORE NIGHT AND MORNING FOG AND LOW CLOUDS INLAND. THE
FOG AND LOW CLOUDS INLAND MAY TAKE A WHILE TO BREAK OUT EACH DAY AS
THE SURFACE GRADIENTS ARE LIGHTER...CAUSING AN EROSION IN AFTERNOON
TEMPS.

THE 12Z ECMWF AND THE GEM ARE NOW STARTING TO SHOW A SYSTEM DROPPING
INTO THE PACIFIC NORTHWEST FROM OVER THE RIDGE LATE NEXT WEEKEND
WHICH COULD BRING AN END TO THE DRY SPELL. THE GFS REMAINS DRY. WILL
CONTINUE THE CURRENT DRY FORECAST BUT WILL NEED TO CHANGE IF THESE
TRENDS CONTINUE. TOLLESON

&&

.AVIATION...IFR CONDITIONS THE RULE BUT MORE SO UNDER STRATUS THAN
FOG. SEEMS LIKE THE LOW LEVEL OFFSHORE FLOW IS SERVING TO LIFT THE
DECK EVER SO SLIGHTLY. TOUGH CALL FOR THE TAFS THIS MORNING BUT AM
STRONGLY CONSIDERING HAVING THE LOW DECKS PREVAIL FOR THE 12Z TAF
PACKAGE VERSUS KEEPING THE FOG IN PLACE. STILL EXPECT NOTABLE
TERRAIN OBSCURATION AROUND THE TERMINALS...HOWEVER. AS SUCH...AM
LOOKING CLOSER TO THE 16 TO 18Z TIME FRAME FOR SCATTERING ACROSS
THE NORTH WHILE HOLDING ON TO THE DECK A LITTLE LONGER FOR THE
SOUTH, SAY 18 TO 20Z. LOOKS LIKE AN IFR OR WORSE DECK WILL
REAPPEAR OVERNIGHT EXCEPT FOR KPDX, KTTD, AND PERHAPS KAST, WHERE
EASTERLY GORGE INFLUENCE WINDS WILL KEEP CONDITIONS CLEARER.

KPDX AND APPROACHES...IFR CIGS THROUGH AROUND 17Z THEN REMAINING VFR
FOR THE REST OF THE PERIOD. /JBONK

&&

.MARINE...MAIN CONCERN IS FOR IMMEDIATE NEAR SHORE SURF CONDITIONS
AS LONG PERIOD SWELL IN PLACE WITH HEIGHTS NOW REACHING 6 FT AT
20 TO 21 SEC. WILL SEE SWELL PEAK NEAR 8 FT WITH WIND WAVES
TACKING ON MAYBE ANOTHER FOOT FOR A TOTAL OF 9 FT FOR THE NORTHERN
OUTER WATERS AT TIMES EARLY THIS EVENING. THIS IS MAKING THE
COLUMBIA BAR FORECAST A BIT PROBLEMATIC AS THE AFTERNOON EBB WILL
BE STRONG AND OCCURRING AROUND THIS SAME TIME. HAVE NOT SEEN MUCH
IN THE WAY OF NOTABLE RISES GIVEN THE ADDED LONG PERIOD ENERGY
PLUS IT IS COMING IN SOMEWHAT ANGLED ACROSS THE PRIMARY FLOW OUT
OF THE MOUTH. WILL SIT TIGHT ON THE CUSP OF ISSUING A ROUGH BAR
ADVISORY UNTIL PERHAPS LATER SHIFTS GAIN ADDED CONFIDENCE FROM
DAYLIGHT OBSERVATIONS. THE LONG PERIOD SWELL WILL SHORTEN
OVERNIGHT AS SEAS GRADUALLY EASE BACK TOWARD 6 FEET OR LESS
HEADING INTO MID WEEK.

WINDS DO GENERALLY STAY IN THE 15 TO 20 KT RANGE FOR GUSTS AND
SLIGHTLY LESS SUSTAINED WINDS. SURFACE LOW PRESSURE JUST OFFSHORE
WILL TURN WINDS LIGHT SOUTHERLY FOR A BIT MIDWEEK. /JBONK


&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PDT THIS MORNING FOR CENTRAL
     OREGON COAST-CENTRAL WILLAMETTE VALLEY-GREATER PORTLAND
     METRO AREA-NORTH OREGON COAST-SOUTH WILLAMETTE VALLEY.

WA...DENSE FOG ADVISORY UNTIL 10 AM PDT THIS MORNING FOR GREATER
     VANCOUVER AREA.

PZ...NONE.

&&

$$

MORE WEATHER INFORMATION ONLINE AT...
    HTTP://WEATHER.GOV/PORTLAND

INTERACT WITH US VIA SOCIAL MEDIA
    WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
    WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.










AREA FORECAST DISCUSSION

NWS PORTLAND OR

 315 AM PDT MON OCT 21 2013

.SYNOPSIS...A STRONG UPPER LEVEL RIDGE ALONG THE COAST CONTINUES TO
DOMINATE THE WEATHER ACROSS THE WESTERN UNITED STATES AND CANADA...
PUSHING THE MAIN PACIFIC STORM TRACK WELL NORTH INTO ALASKA. THIS
WILL MAINTAIN DRY WEATHER WITH MILD DAYS AND COOL NIGHTS IN SOUTHWEST
WASHINGTON AND NORTHWEST OREGON...ALONG WITH AREAS OF DENSE NIGHT AND
MORNING FOG. A BIT OF EAST WIND SHOULD DEVELOP IN THE GORGE
AND SPREAD INTO THE PORTLAND AND VANCOUVER METRO AREA MONDAY NIGHT...
LEADING TO LESS FOG IN THESE AREAS TUESDAY MORNING. AFTER SOME
POSSIBLE COASTAL DRIZZLE WEDNESDAY THE FORECAST LOOKS DRY.

&&

.SHORT TERM...MONDAY THROUGH WEDNESDAY...
THINGS ARE PROGRESSING IN A SOMEWHAT SIMILAR FASHION TO LAST
NIGHT...WITH THE MINOR EXCEPTION THAT WE ARE STARTING TO DEVELOP AN
OFFSHORE GRADIENT THROUGH THE COLUMBIA RIVER GORGE AND ALONG THE
EAST SIDE OF THE WARNING AREAS. INVERSIONS ARE IN PLACE TO KEEP THE
EAST WIND FROM SURFACING OUTSIDE OF THE GORGE JUST YET. THAT MEANS
FAIRLY LIGHT WINDS TO EVEN A LIGHT NORTHWEST WIND AROUND PORTLAND
THAT IS JOINING WITH RADIATIONAL PROCESSES TO BRING LOW CLOUDS AND
FOG IN FROM THE NORTH WHERE IT HAS BEEN LOCKED IN PLACE FOR THE PAST
FEW DAYS. THE COWLITZ RIVER VALLEY AND KELSO/LONGVIEW AREAS ARE
AGAIN SEEING LOW STRATUS RATHER THAN DENSE FOG...AS THE COLD POOL
STRATUS OVER THE PUGET SOUND PUSHES INTO THE AREA BEFORE FOG CAN
DEVELOP. MEANWHILE AT THE COAST...FOG IS DENSE FROM ABOUT LINCOLN
CITY SOUTHWARD...WHILE EAST WINDS ARE SHOWING UP NEAR ASTORIA KEEPING
THINGS AT BAY. STILL THINK RADIATIONAL PROCESSES WILL ALLOW FOR SOME
FOG HERE TOO.

WE DO HAVE WIDELY VARYING VISIBILITIES...BUT LATEST HRRR GUIDANCE FOR
SFC VISIBILITY WHICH HAD A DECENT HANDLE ON THE DENSE FOG YESTERDAY
SUGGESTS IT REMAINS A CONCERN THROUGH THE VALID TIME OF THE CURRENT
ADVISORY. HAVE SOME CONCERNS THAT WITH THE WINDS ABOVE THE SURFACE
BEING A BIT STRONGER TODAY WITH THE OFFSHORE GRADIENT THAT THE FOG
WILL ONLY REMAIN DENSE IN WIND SHELTERED LOCATIONS AND THAT IT WILL
LIFT TO A LOW STRATUS DECK AS IS NOW TAKING PLACE IN SEVERAL
LOCATIONS.  WILL HANG ONTO THE VALLEY ADVISORY FOR NOW AND MONITOR
THE TRENDS AS WE STILL HAVE PLENTY OF SPOTS AT THREE QUARTERS OF A
MILE VISIBILITY OR LESS AND QUARTER MILE VISIBILITY AT HILLSBORO AND
MCMINNVILLE. ELEVATED LOCATIONS MAY BE IN THE LOW CLOUD AND THUS IN
THE FOG ANYWAYS AND CAMERAS ON I-205 DO SHOW SOME PRETTY DENSE FOG
AS OF 300 AM. MEANWHILE...THE HRRR ALSO SUGGESTS THE CENTRAL COAST
WILL HANG ONTO DENSE FOG AND ON THE NORTH COAST FROM TILLAMOOK
SOUTH. FEEL THESE AREAS WILL KEEP LIGHT WINDS UNDER THE COASTAL LOW
TO WARRANT ADDITION OF THE CENTRAL COAST INTO THE ADVISORY...AND
WILL ADD THE NORTH COAST TOO DESPITE IT BEING FOCUSED ON THE
SOUTHERN HALF OF THE ZONE.  AREAS NORTH TOWARD ASTORIA AND INTO THE
SOUTH WASHINGTON COAST ARE FEELING THE EAST WIND A BIT MORE AS SEEN
IN THE MSLP ANALYSIS. ALL LOWLAND AREAS MAY ALSO EXPERIENCE SOME
DRIZZLY MIST OUT OF THE LOW CLOUDS WHEN HEADING OUT THIS MORNING.

THE COLD POOL DEEPENS LATER THIS MORNING...WHICH ALLOWS HIGH PRESSURE
TO STRENGTHEN ENOUGH EAST OF THE CASCADES TO PUSH THE EASTERLY
PRESSURE GRADIENTS INTO THE PORTLAND METRO AREA. MONDAY NIGHT/EARLY
TUESDAY APPEARS TO BE THE TIME PERIOD WHERE FOG WILL HAVE A HARD
TIME RE-FORMING AROUND THE PDX METRO DUE TO MODERATE EASTERLY GORGE
WINDS. THERE MAY BE ENOUGH OFFSHORE COMPONENT TO KEEP THE NORTH
COAST CLEAR MON NIGHT AS WELL. AS A RESULT THESE AREAS SHOULD BE A
FEW DEGREES WARMER ON TUESDAY. EXPECT TEMPERATURES TODAY TO BE
SOMEWHAT ON PAR WITH YESTERDAY...THOUGH GUIDANCE SUGGESTS A SMALL
INCREASE ESPECIALLY FOR LOCATIONS WHERE LOW CLOUDS AND FOG LINGER
THE LEAST. /KMD

REST OF THE SHORT TERM DISCUSSION UNCHANGED...EASTERLY WINDS SHOULD
CONTINUE THROUGH THE GORGE AND ACROSS THE
PORTLAND/VANCOUVER METRO TUE NIGHT/EARLY WED...BUT SHOULD BEGIN TO
EASE AS HIGH PRESSURE WEAKENS EAST OF THE CASCADES. HOWEVER...AT THE
SAME TIME A WEAK UPPER LEVEL CUTOFF LOW WILL BE MEANDERING CLOSER TO
THE OREGON COAST. THIS MAY KEEP FLOW EASTERLY ACROSS THE NORTHERN
HALF OF OUR FORECAST AREA...WHILE DEEPENING THE MARINE LAYER AND
INDUCING A SOUTHERLY WIND REVERSAL ALONG THE CENTRAL OREGON COAST.
THE DEEPENING MARINE LAYER MAY BE ENOUGH TO WRING OUT SOME COASTAL
DRIZZLE AND COULD EVENTUALLY SPREAD COASTAL LOW CLOUDS INTO THE
WILLAMETTE VALLEY.  WEAGLE

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...WEDNESDAY
NIGHT THROUGH SUNDAY...THE WEAK DRY LOW CIRCULATION OFF THE OREGON
COAST AT THE END OF THE SHORT TERM PERIOD WILL DRIFT NORTH TOWARD
B.C. DURING THE FIRST PART OF THE LANG TERM PERIOD...REPLACED BY A
LARGER LOW OFF THE CALIFORNIA COAST. WE LOOK TO STAY DRY...THOUGH WE
WILL HAVE A BIT MORE PERSISTENT LOW LEVEL MARINE LAYER NEAR THE
COAST...WITH MORE NIGHT AND MORNING FOG AND LOW CLOUDS INLAND. THE
FOG AND LOW CLOUDS INLAND MAY TAKE A WHILE TO BREAK OUT EACH DAY AS
THE SURFACE GRADIENTS ARE LIGHTER...CAUSING AN EROSION IN AFTERNOON
TEMPS.

THE 12Z ECMWF AND THE GEM ARE NOW STARTING TO SHOW A SYSTEM DROPPING
INTO THE PACIFIC NORTHWEST FROM OVER THE RIDGE LATE NEXT WEEKEND
WHICH COULD BRING AN END TO THE DRY SPELL. THE GFS REMAINS DRY. WILL
CONTINUE THE CURRENT DRY FORECAST BUT WILL NEED TO CHANGE IF THESE
TRENDS CONTINUE. TOLLESON

&&

.AVIATION...IFR CONDITIONS THE RULE BUT MORE SO UNDER STRATUS THAN
FOG. SEEMS LIKE THE LOW LEVEL OFFSHORE FLOW IS SERVING TO LIFT THE
DECK EVER SO SLIGHTLY. TOUGH CALL FOR THE TAFS THIS MORNING BUT AM
STRONGLY CONSIDERING HAVING THE LOW DECKS PREVAIL FOR THE 12Z TAF
PACKAGE VERSUS KEEPING THE FOG IN PLACE. STILL EXPECT NOTABLE
TERRAIN OBSCURATION AROUND THE TERMINALS...HOWEVER. AS SUCH...AM
LOOKING CLOSER TO THE 16 TO 18Z TIME FRAME FOR SCATTERING ACROSS
THE NORTH WHILE HOLDING ON TO THE DECK A LITTLE LONGER FOR THE
SOUTH, SAY 18 TO 20Z. LOOKS LIKE AN IFR OR WORSE DECK WILL
REAPPEAR OVERNIGHT EXCEPT FOR KPDX, KTTD, AND PERHAPS KAST, WHERE
EASTERLY GORGE INFLUENCE WINDS WILL KEEP CONDITIONS CLEARER.

KPDX AND APPROACHES...IFR CIGS THROUGH AROUND 17Z THEN REMAINING VFR
FOR THE REST OF THE PERIOD. /JBONK

&&

.MARINE...MAIN CONCERN IS FOR IMMEDIATE NEAR SHORE SURF CONDITIONS
AS LONG PERIOD SWELL IN PLACE WITH HEIGHTS NOW REACHING 6 FT AT
20 TO 21 SEC. WILL SEE SWELL PEAK NEAR 8 FT WITH WIND WAVES
TACKING ON MAYBE ANOTHER FOOT FOR A TOTAL OF 9 FT FOR THE NORTHERN
OUTER WATERS AT TIMES EARLY THIS EVENING. THIS IS MAKING THE
COLUMBIA BAR FORECAST A BIT PROBLEMATIC AS THE AFTERNOON EBB WILL
BE STRONG AND OCCURRING AROUND THIS SAME TIME. HAVE NOT SEEN MUCH
IN THE WAY OF NOTABLE RISES GIVEN THE ADDED LONG PERIOD ENERGY
PLUS IT IS COMING IN SOMEWHAT ANGLED ACROSS THE PRIMARY FLOW OUT
OF THE MOUTH. WILL SIT TIGHT ON THE CUSP OF ISSUING A ROUGH BAR
ADVISORY UNTIL PERHAPS LATER SHIFTS GAIN ADDED CONFIDENCE FROM
DAYLIGHT OBSERVATIONS. THE LONG PERIOD SWELL WILL SHORTEN
OVERNIGHT AS SEAS GRADUALLY EASE BACK TOWARD 6 FEET OR LESS
HEADING INTO MID WEEK.

WINDS DO GENERALLY STAY IN THE 15 TO 20 KT RANGE FOR GUSTS AND
SLIGHTLY LESS SUSTAINED WINDS. SURFACE LOW PRESSURE JUST OFFSHORE
WILL TURN WINDS LIGHT SOUTHERLY FOR A BIT MIDWEEK. /JBONK


&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PDT THIS MORNING FOR CENTRAL
     OREGON COAST-CENTRAL WILLAMETTE VALLEY-GREATER PORTLAND
     METRO AREA-NORTH OREGON COAST-SOUTH WILLAMETTE VALLEY.

WA...DENSE FOG ADVISORY UNTIL 10 AM PDT THIS MORNING FOR GREATER
     VANCOUVER AREA.

PZ...NONE.

&&

$$

MORE WEATHER INFORMATION ONLINE AT...
    HTTP://WEATHER.GOV/PORTLAND

INTERACT WITH US VIA SOCIAL MEDIA
    WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
    WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.







AREA FORECAST DISCUSSION

NWS HOUSTON/GALVESTON TX

 1000 AM CDT MON OCT 21 2013

.UPDATE...
WIDESPREAD SOUTHERN CWA SHOWERS...WITH OCCASIONAL THUNDER...MOVING
QUICKLY NORTHEAST AT AROUND 40 MPH. THE BULK OF TODAY`S PRECIPITATION
WILL FALL ALONG AND SOUTH OF HIGHWAY 59...OR WHERE THE MOST EFFICIENT
UPPER LEVEL FORCING RESIDES. THE UPPER TEXAS COAST FALLING IN THE
RRQ OF A SOUTHEASTERN U.S. 3H JET WITH A DISTURBANCE RIDING UP AHEAD
OF A CENTRAL TEXAS SHORTWAVE TROUGH. ADDITIONAL CONVECTIVE FOCUS
IS BEING PROVIDED BY A NEAR-STATIONARY WARM FRONTAL BOUNDARY ALONG
THE COAST. THIS EVENING INTO EARLY TUESDAY MORNING`S COLD FRONTAL
PASSAGE ON SCHEDULE TO PASS OVER THE NORTHERN FA TONIGHT...TO THE
COAST BEFORE SUNRISE TOMORROW. PARTIALLY TO MOSTLY OVERCAST WITH
RAIN/ISOLATED STORMS PRIMARILY CONFINED TO SOUTHERN THIRD OF REGION
TODAY...TEMPERATURES WILL CLIMB INTO THE AVERAGE UPPER 70S BY 4 PM.
POST-FRONTAL COOLER AND MUCH DRIER CONDITIONS TOMORROW...INLAND
MORNING MINIMUMS IN THE 50S (60S COAST)...WARMING INTO THE VERY
COMFORTABLE MID 70S. 31

&&

.PREV DISCUSSION... /ISSUED 636 AM CDT MON OCT 21 2013/

DISCUSSION...
SEE AVIATION FOR 12Z TAF DISCUSSION

AVIATION...
LIGHT SHRA TO THE WEST OF THE TERMINALS THIS MORNING ASSOCIATED
WITH A WEAK SHORTWAVE DISTURBANCE OVER SAT. EXPECT SHRA COVERAGE
TO INCREASE BY LATE MORNING AS UPPER DISTURBANCE MOVES OVERHEAD. A
COLD FRONT CURRENTLY STRETCHING FROM NEAR FST-SPS-TUL WILL
APPROACH THE REGION TODAY REACHING CLL BY 03Z TUESDAY AND THE
METRO TERMINALS BETWEEN 08-10Z. A BRIEF PERIOD OF MVFR CIGS IS
POSSIBLE AS THE FRONT PASSES THROUGH THE REGION...CLEARING THE
COAST AT THE END OF THE CURRENT TAF PERIOD. 38

PREV DISCUSSION... /ISSUED 442 AM CDT MON OCT 21 2013/

DISCUSSION...
BASED ON 00Z UPPER AIR ANALYSIS AND WATER VAPOR IMAGERY...FIRST
OF A COUPLE OF SHORT WAVE TROUGHS IS AFFECTING SE TX THIS MORNING.
UPWARD VERTICAL MOTION FROM THE FIRST SHORTWAVE IS SUPPORTING
CONVECTION BETWEEN VICTORIA AND WHARTON THIS MORNING ON RADAR
IMAGERY. ALSO GETTING QUITE A BIT OF CONVECTION TO DEVELOP OFF THE
LOWER TX COAST AND S TX. SECOND MORE SIGNIFICANT TROUGH AXIS IS
BACK OVER THE S ROCKIES AND SHOULD BE PUSHING THROUGH LATER TODAY
AND TONIGHT AS IT SHEARS OUT. JET STEAM IS ALSO EXPECTED TO BECOME
MORE FAVORABLE FOR UPWARD MOTION AS IT STRENGTHENS OVER THE MID
SOUTH AND POSITIONS DIVERGENCE OVER SE TX FROM RIGHT ENTRANCE
REGION OF THE JET. EXPECT THERE TO BE SOME ISENTROPIC LIFT AS WELL
FROM DISSIPATING FRONTAL BOUNDARY IN THE GULF. ALL OF THIS SHOULD
SUPPORT SOME RAINFALL ACROSS THE SOUTHERN PORTION OF SE TX AND
ALONG THE COAST. THE 06Z HRRR AND 00Z TX TECH WRF KEEP MOST OF THE
PRECIP OFF THE COAST AND HAVE ORIENTED POPS AS SUCH. POPS MAY BE
ABOUT 10 PERCENT TOO HIGH ACROSS THE BOARD FOR INLAND AREAS BUT
THINK THAT MOST AREAS WILL SEE AT LEAST SOME RAIN...JUST LOWER
AMOUNTS. LOOKS LIKE THE COASTAL COUNTIES WILL LIKELY HAVE MAYBE
0.25-0.5 INCHES OF RAIN. AN 1 INCH TOTALS WILL BE OUT IN THE GULF.
THE REST OF SE TX LIKELY HAVE A TENTH OF AN INCH IF THAT. DESPITE
CLOUD COVER STILL THINK MAX TEMPS IN THE UPPER 70S LOOK GOOD WITH
MOISTURE AND WARM ADVECTION IN PLACE TODAY.

COLD FRONT CURRENTLY WORKING THROUGH OKLA AND W TX WILL PUSH INTO
SE TX TONIGHT AND OFF THE COAST BY 12Z TUE. THIS SHOULD END ANY
RAIN CHANCES FOR SE TX WITH THE BULK OF THE PRECIP IN THE GULF
HEADED TOWARDS N GULF COAST. COLD ADVECTION DURING THE DAY SHOULD
KEEP MAX TEMPS IN THE MID 70S ALONG THE COAST AND LOW 70S FARTHER
INLAND. HIGH PRESSURE WILL BUILD OVER SE TX FOR WED MORNING SO
EXPECT MIN TEMPS BACK IN THE UPPER 40S TO LOW 50S.

NEAR TO BELOW NORMAL TEMPERATURES ARE LIKELY TO CONTINUE THE REST
OF THE WEEK. UPPER LEVEL PATTERN SHOULD BE QUITE AMPLIFIED WITH
LONG WAVE TROUGH OVER THE GREAT LAKES AND NW FLOW ACROSS THE
PLAINS DUE TO RIDGING OVER THE WEST COAST. SHORT WAVE TROUGH STILL
EXPECTED TO IMPACT N TX THROUGH SE TX ON SATURDAY BUT LOOKS MUCH
WEAKER. MOISTURE WILL ALSO BE LIMITED SO BACKED OFF ON POPS SOME
BUT KEPT A PERIOD OF 20 POPS FOR NORTHERN AREAS OF SE TX WHERE
LIFT MAY BE MAXIMIZED. OTHERWISE FORECAST SHOULD BE DRY THROUGH
THE WEEKEND. TEMPERATURES WERE NOT ADJUSTED VERY MUCH BUT DID
TREND TEMPS COOLER FOR THE WEEKEND. ANOTHER AREA OF HIGH PRESSURE
WILL BUILD OVER THE MISS RIVER VALLEY WITH NE/E BOUNDARY LAYER
FLOW OVER SE TX. THIS SHOULD ALLOW FOR COOLER AIR TO FILTER INTO
THE REGION FOR THE WEEKEND. THIS WILL LIKELY KEEP TEMPS NEAR
NORMAL OR EVEN A DEGREE OR TWO BELOW NORMAL. 39

MARINE...
ONSHORE FLOW THIS MORNING WILL PERSIST THROUGH THE DAY AHEAD OF A
COLD FRONT WHICH WILL PUSH OFFSHORE JUST BEFORE DAYBREAK ON
TUESDAY. CAUTION FLAGS WILL BE NEEDED IN THE WAKE OF THE FRONT
WITH ADVISORY CONDITIONS POSSIBLE FOR A BRIEF PERIOD ON TUESDAY.
EXPECT BRISK NORTH AND NORTHEAST WINDS THROUGH THE END OF THE WEEK
WITH CAUTION FLAGS POSSIBLE FOR MOST OF THE WEEK. 38

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      78  53  73  51  77 /  20  20  10  10  10
HOUSTON (IAH)              80  59  75  52  78 /  50  20  10  10  10
GALVESTON (GLS)            79  66  76  62  77 /  90  40  10  10  10

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&

$$

DISCUSSION...31/43




AREA FORECAST DISCUSSION

NWS HOUSTON/GALVESTON TX

 636 AM CDT MON OCT 21 2013

.DISCUSSION...
SEE AVIATION FOR 12Z TAF DISCUSSION

&&

.AVIATION...
LIGHT SHRA TO THE WEST OF THE TERMINALS THIS MORNING ASSOCIATED
WITH A WEAK SHORTWAVE DISTURBANCE OVER SAT. EXPECT SHRA COVERAGE
TO INCREASE BY LATE MORNING AS UPPER DISTURBANCE MOVES OVERHEAD. A
COLD FRONT CURRENTLY STRETCHING FROM NEAR FST-SPS-TUL WILL
APPROACH THE REGION TODAY REACHING CLL BY 03Z TUESDAY AND THE
METRO TERMINALS BETWEEN 08-10Z. A BRIEF PERIOD OF MVFR CIGS IS
POSSIBLE AS THE FRONT PASSES THROUGH THE REGION...CLEARING THE
COAST AT THE END OF THE CURRENT TAF PERIOD. 38

&&

.PREV DISCUSSION... /ISSUED 442 AM CDT MON OCT 21 2013/

DISCUSSION...
BASED ON 00Z UPPER AIR ANALYSIS AND WATER VAPOR IMAGERY...FIRST
OF A COUPLE OF SHORT WAVE TROUGHS IS AFFECTING SE TX THIS MORNING.
UPWARD VERTICAL MOTION FROM THE FIRST SHORTWAVE IS SUPPORTING
CONVECTION BETWEEN VICTORIA AND WHARTON THIS MORNING ON RADAR
IMAGERY. ALSO GETTING QUITE A BIT OF CONVECTION TO DEVELOP OFF THE
LOWER TX COAST AND S TX. SECOND MORE SIGNIFICANT TROUGH AXIS IS
BACK OVER THE S ROCKIES AND SHOULD BE PUSHING THROUGH LATER TODAY
AND TONIGHT AS IT SHEARS OUT. JET STEAM IS ALSO EXPECTED TO BECOME
MORE FAVORABLE FOR UPWARD MOTION AS IT STRENGTHENS OVER THE MID
SOUTH AND POSITIONS DIVERGENCE OVER SE TX FROM RIGHT ENTRANCE
REGION OF THE JET. EXPECT THERE TO BE SOME ISENTROPIC LIFT AS WELL
FROM DISSIPATING FRONTAL BOUNDARY IN THE GULF. ALL OF THIS SHOULD
SUPPORT SOME RAINFALL ACROSS THE SOUTHERN PORTION OF SE TX AND
ALONG THE COAST. THE 06Z HRRR AND 00Z TX TECH WRF KEEP MOST OF THE
PRECIP OFF THE COAST AND HAVE ORIENTED POPS AS SUCH. POPS MAY BE
ABOUT 10 PERCENT TOO HIGH ACROSS THE BOARD FOR INLAND AREAS BUT
THINK THAT MOST AREAS WILL SEE AT LEAST SOME RAIN...JUST LOWER
AMOUNTS. LOOKS LIKE THE COASTAL COUNTIES WILL LIKELY HAVE MAYBE
0.25-0.5 INCHES OF RAIN. AN 1 INCH TOTALS WILL BE OUT IN THE GULF.
THE REST OF SE TX LIKELY HAVE A TENTH OF AN INCH IF THAT. DESPITE
CLOUD COVER STILL THINK MAX TEMPS IN THE UPPER 70S LOOK GOOD WITH
MOISTURE AND WARM ADVECTION IN PLACE TODAY.

COLD FRONT CURRENTLY WORKING THROUGH OKLA AND W TX WILL PUSH INTO
SE TX TONIGHT AND OFF THE COAST BY 12Z TUE. THIS SHOULD END ANY
RAIN CHANCES FOR SE TX WITH THE BULK OF THE PRECIP IN THE GULF
HEADED TOWARDS N GULF COAST. COLD ADVECTION DURING THE DAY SHOULD
KEEP MAX TEMPS IN THE MID 70S ALONG THE COAST AND LOW 70S FARTHER
INLAND. HIGH PRESSURE WILL BUILD OVER SE TX FOR WED MORNING SO
EXPECT MIN TEMPS BACK IN THE UPPER 40S TO LOW 50S.

NEAR TO BELOW NORMAL TEMPERATURES ARE LIKELY TO CONTINUE THE REST
OF THE WEEK. UPPER LEVEL PATTERN SHOULD BE QUITE AMPLIFIED WITH
LONG WAVE TROUGH OVER THE GREAT LAKES AND NW FLOW ACROSS THE
PLAINS DUE TO RIDGING OVER THE WEST COAST. SHORT WAVE TROUGH STILL
EXPECTED TO IMPACT N TX THROUGH SE TX ON SATURDAY BUT LOOKS MUCH
WEAKER. MOISTURE WILL ALSO BE LIMITED SO BACKED OFF ON POPS SOME
BUT KEPT A PERIOD OF 20 POPS FOR NORTHERN AREAS OF SE TX WHERE
LIFT MAY BE MAXIMIZED. OTHERWISE FORECAST SHOULD BE DRY THROUGH
THE WEEKEND. TEMPERATURES WERE NOT ADJUSTED VERY MUCH BUT DID
TREND TEMPS COOLER FOR THE WEEKEND. ANOTHER AREA OF HIGH PRESSURE
WILL BUILD OVER THE MISS RIVER VALLEY WITH NE/E BOUNDARY LAYER
FLOW OVER SE TX. THIS SHOULD ALLOW FOR COOLER AIR TO FILTER INTO
THE REGION FOR THE WEEKEND. THIS WILL LIKELY KEEP TEMPS NEAR
NORMAL OR EVEN A DEGREE OR TWO BELOW NORMAL.

39

MARINE...
ONSHORE FLOW THIS MORNING WILL PERSIST THROUGH THE DAY AHEAD OF A
COLD FRONT WHICH WILL PUSH OFFSHORE JUST BEFORE DAYBREAK ON
TUESDAY. CAUTION FLAGS WILL BE NEEDED IN THE WAKE OF THE FRONT
WITH ADVISORY CONDITIONS POSSIBLE FOR A BRIEF PERIOD ON TUESDAY.
EXPECT BRISK NORTH AND NORTHEAST WINDS THROUGH THE END OF THE WEEK
WITH CAUTION FLAGS POSSIBLE FOR MOST OF THE WEEK. 38

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      78  54  73  51  77 /  30  20  10  10  10
HOUSTON (IAH)              79  58  75  52  78 /  50  20  10  10  10
GALVESTON (GLS)            79  67  77  62  77 /  50  40  10  10  10

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&

$$

DISCUSSION...39
AVIATION/MARINE...38




AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 926 AM CDT MON OCT 21 2013

.UPDATE...TODAY
ISSUED AT 926 AM CDT MON OCT 21 2013

ADDED SCATTERED FLURRIES TO MUCH OF THE FORECAST AREA TODAY AS
SUBTLE SHORTWAVE TROUGH ROUNDS THE BASE OF THE UPPER LEVEL LOW.
DEPTH OF THE LOW LEVEL CLOUD DECK OFF THE 21.12Z MPX SOUNDING AND
FORECAST RAP SOUNDINGS FOR THIS MORNING INTO THE AFTERNOON HOURS
RANGES FROM 2 TO 6 KFT...IN CONJUNCTION WITH WEAK LIFT...AND LAPSE
RATES WILL BE SUFFICIENTLY STEEP FOR WEAK CONVECTIVE INSTABILITY
SNOW SHOWERS OR FLURRIES TO DEVELOP. UPSTREAM REPORTS FROM THE
TWIN CITIES AREA OF SNOW FLURRIES MATCHES WITH THE WEAK RADAR
RETURNS. SKIES WILL BE OVERCAST FOR MUCH OF THE DAY...AND
TEMPERATURES WILL STRUGGLE TO RISE A LOT. LOWERED HIGHS A BIT TO
ACCOUNT FOR THIS.

&&

.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 259 AM CDT MON OCT 21 2013

THE SURFACE LOW THAT MOVED ACROSS THE REGION SUNDAY IS MOVING
ACROSS NORTHERN LAKE MICHIGAN EARLY THIS MORNING. A TROUGH OF LOW
PRESSURE EXTENDS NORTHWEST FROM THE LOW ACROSS LAKE SUPERIOR INTO
SOUTHERN CANADA. THE SURFACE LOW IS EXPECTED TO KEEP MOVING
NORTHEAST TOWARD HUDSON BAY TODAY AND AS IT DOES...THE TROUGH OF
LOW PRESSURE SHOULD PIVOT AROUND THE BACK SIDE OF THE LOW AND
EXTEND FROM THE LOW BACK TO THE SOUTHWEST ACROSS LAKE SUPERIOR.
THIS IS FARTHER NORTH THAN EARLIER MODELS RUNS WERE
INDICATED...BUT THIS NORTHWARD SHIFT IN POSITION OF THE TROUGH HAS
BEEN A CONSISTENT TREND IN THE MODELS AS WELL. THIS WILL ALL OCCUR
AS THE UPPER LEVEL LOW OVER THE SOUTHWEST CORNER OF ONTARIO STARTS
TO TURN SOUTHEAST AND MOVE TOWARD THE U.P. OF MICHIGAN TODAY. THE
FORCING WITH THE UPPER LEVEL LOW IS EXPECTED TO STAY WELL TO THE
NORTHEAST OF THE AREA WITH ALL THE QG CONVERGENCE STAYING OVER
LAKE SUPERIOR INTO ONTARIO. THE 21.00Z MODELS HAVE ALSO REMAINED
CONSISTENT IN SHOWING THE DEEPEST MOISTURE STAYING ALONG AND NORTH
OF THE SURFACE TROUGH WITH STRONG MID LEVEL DRYING WORKING IN
UNDERNEATH THE UPPER LEVEL LOW. WITH THE SURFACE TROUGH FARTHER TO
THE NORTH AND THE EXPECTED MID LEVEL DRYING...REMOVED THE MENTION
OF ANY PRECIPITATION ACROSS THE AREA FOR TODAY.

THE FOCUS THEN TURNS TO THE NEXT SHORT WAVE TROUGH TO COME DOWN
IN THE NORTHWEST FLOW FOR LATE TONIGHT INTO TUESDAY. THE MODELS
ARE ALL FAIRLY CONSISTENT IN SHOWING THIS WAVE PASSING BY TO THE
SOUTHWEST OF THE AREA BUT CLOSE ENOUGH TO PRODUCE AS MUCH AS 8
PVU/S OF VORTICITY ADVECTION IN THE 500-300 MB LAYER ACROSS THE
SOUTHERN PARTS OF THE FORECAST AREA LATE TONIGHT INTO TUESDAY
MORNING. WEAK TO MODERATE QG CONVERGENCE SHOULD OCCUR IN THE
1000-300 MB LAYER WITH THIS WAVE MAINLY ACROSS NORTHEAST IOWA.
WITH THE SURFACE LOW EXPECTED TO TRACK FROM SOUTHEAST SOUTH
DAKOTA TO NORTHERN MISSOURI TONIGHT THROUGH TUESDAY MORNING...ALL
THE ISENTROPIC UP GLIDE REMAINS CLOSE TO THE SURFACE LOW AND SOUTH
OF THE AREA. ENOUGH FORCING FROM THIS SYSTEM TO JUSTIFY HAVING A
CHANCE OF PRECIPITATION ACROSS THE SOUTH FOR LATE TONIGHT THROUGH
TUESDAY MORNING. SOUNDINGS SUGGEST PLENTY OF ICE WILL BE AVAILABLE
IN THE CLOUDS AND EXPECT ANY PRECIPITATION TYPE ISSUES TO BE
CONTROLLED BY LOW LEVEL TEMPERATURES. SO EXPECT THIS TO MAINLY BE
SNOW POSSIBLY MIXING WITH SOME RAIN TOWARD THE END OF THE EVENT
TUESDAY MORNING.

COULD BE A VERY SIMILAR SYSTEM COMING THROUGH THE NORTHWEST FLOW
FOR WEDNESDAY. THE 21.00Z GFS AND ECMWF BOTH SHOW THE SURFACE LOW
DROPPING SOUTHEAST THROUGH THE MISSOURI RIVER VALLEY AND BRUSHING
THE SOUTHWEST SECTIONS OF THE FORECAST AREA WITH SOME
PRECIPITATION WHILE THE 21.00Z NAM BARELY SHOWS ANYTHING. BASED ON
THE AGREEMENT BETWEEN THE GFS AND ECMWF...ADDED IN A SMALL CHANCE
OF SOME PRECIPITATION ACROSS THE SOUTHWEST PARTS OF THE AREA.

.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 259 AM CDT MON OCT 21 2013

THE NORTHWEST FLOW ALOFT IS EXPECTED TO CONTINUE UNTIL POSSIBLY
VERY LATE IN THE PERIOD WHEN THERE IS SOME SUGGESTION OF THE
WESTERN RIDGE BREAKING DOWN ALLOWING THE FLOW OVER THE UPPER
MIDWEST TO BECOME ZONAL. MODELS ALSO CONTINUE TO SHOW A SYSTEM
COMING ACROSS THE GREAT LAKES REGION IN THE NORTHWEST FLOW IN THE
FRIDAY NIGHT INTO SATURDAY TIME FRAME. HOWEVER...STILL SOME
DIFFERENCES ON THE TRACK OF THE SYSTEM WITH THE GFS BRINGING THE
SURFACE LOW ACROSS WISCONSIN AND SHOWING PRECIPITATION OVER THE
AREA WHILE THE 22.00Z ECMWF TAKES THE SURFACE ACROSS ONTARIO
KEEPING THE AREA DRY. THE 22.00Z GEM LOOKS TO BE MUCH WEAKER WITH
NO SURFACE LOW BUT DOES PRODUCE SOME PRECIPITATION ACROSS
NORTHEAST WISCONSIN. FOR NOW...WILL STAY WITH THE MODEL CONSENSUS
GRIDS AND SHOW SOME SMALL PRECIPITATION CHANCES FOR FRIDAY NIGHT
AND SATURDAY. BELOW TEMPERATURES TO CONTINUE THROUGH THE
PERIOD...BUT SOME WARMING POSSIBLE FOR NEXT WEEKEND...POSSIBLY
APPROACHING 50 ACROSS THE FAR SOUTH.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 650 AM CDT MON OCT 21 2013

A WEAK TROUGH WILL GENERATE ISOLATED SHOWERS ACROSS WESTERN
WISCONSIN THROUGH 21.15Z. SINCE THE MESO MODELS SUGGEST THAT THESE
SHOWERS WILL BE EAST OF KLSE...IT WAS NOT INCLUDED IN THE TAF.
OVERALL THE MAIN CONCERN IN THE FORECAST WILL BE THE CLOUDS. SOME
MVFR CLOUDS WILL CONTINUE TO BE SEEN IN KLSE THROUGH 21.14Z AND
THEN THE CEILINGS WILL REMAIN IN THE 4 TO 6K RANGE INTO THIS
EVENING. THE MODELS HINT THAT THESE CLOUDS WILL BECOME SCATTERED
BECOME 21.21Z AND 22.03Z. HOWEVER WITH MODELS NOT DOING THE
GREATEST ON THIS CLEARING ACROSS MANITOBA AT THE MOMENT...DECIDED
TO DELAY THIS CLEARING UNTIL AFTER 22.06Z. THIS IS CORRESPONDING
TO THE INVERSION RISING AHEAD OF THE NEXT SHORT WAVE TROUGH.


&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&

$$

UPDATE...ZT
SHORT TERM...04
LONG TERM...04
AVIATION...BOYNE








AREA FORECAST DISCUSSION

NWS PEACHTREE CITY GA

 232 PM EDT MON OCT 21 2013

...QUICK SHOT OF RAIN TUESDAY BEFORE COLDER AIR ARRIVES...

.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...

LATEST SURFACE ANALYSIS OF THE SOUTHEAST STATES SHOWS HIGH
PRESSURE RIDGE REMAINS IN CONTROL BUT INFLUENCE IS WEAKENING. THIS
IS DUE TO THE APPROACH OF AN UPPER LEVEL TROUGH WHICH RUC ANALYSIS
HAS SITUATED FROM EASTERN ILLINOIS THROUGH MISSOURI AND KANSAS AS
WELL AS ADDITIONAL RIPPLES OF UPPER LEVEL ENERGY CLOSER TO HOME
EMBEDDED IN BROADER TROUGH REGIME. AS FAR AS THE SENSIBLE WEATHER
THIS HAS PRODUCED AT THE SURFACE...PRETTY MUCH A MIXED BAG WITH
LOW CLOUDS IN VICINITY OF RIDGE AXIS AROUND ATHENS JUST STARTING
TO BREAK UP AND A MOSTLY SUNNY DAY ELSEWHERE WHICH IS QUICKLY
GIVING WAY TO INCREASED CIRRUS IN SW FLOW ALOFT. SOME LIGHT
RETURNS FORM THIS ON RADAR FOR SOUTHERN SECTIONS BUT NO EVIDENCE
ANY OF THIS IS REACHING THE GROUND JUST YET.

FOR TONIGHT...GULF COAST WAVE AT THE UPPER LEVELS WILL MOVE INTO
SOUTH GEORGIA THIS EVENING ALLOWING FOR INCREASED LIFT AND
MOISTURE BOTH AT THE MID LEVELS AND EVENTUALLY LOW LEVELS BY
DAYBREAK. IN FACT...MODELS INDICATE LOW CLOUDS REDEVLOPING ACROSS
THE SE ZONES WITH SOME POTENTIAL FOR REDUCED VSBY AS WELL PRIOR TO
DAYBREAK. EXPECT THICKENING CLOUD DECK AND AFOREMENTIONED LIFT TO
RESULT IN -RA WITH LOW END CHANCE ADVERTISED FOR NOW. THIS MAY
PROVE TO BE TOO LOW GIVEN THE AMOUNT OF OMEGA INDICATED BY THE
MODELS BUT HAVE AT LEAST RAMPED UP SOME 10 TO 20 PERCENT ABOVE
GUIDANCE.

SAME HOLDS TRUE FOR TUESDAY AS GUIDANCE POPS LOOK MUCH TOO LOW FOR
THE AMOUNT OF MOISTURE AND LIFT INDICATED BY THE
MODELS...ESPECIALLY THE NAM12. SETUP LOOKS AN AWFUL LOT LIKE THIS
PAST SATURDAY WHEN GUIDANCE HAD NO CLUE AND RAIN WAS MUCH MORE
WIDESPREAD THAN EXPECTED. WITH SECONDARY SHOT OF ENERGY COMING
ACROSS LATE IN THE DAY...FEEL LOW END CHANCE POPS AT LEAST ARE
WARRANTED AND THESE MAY NEED TO BE INCREASED FURTHER IF TRENDS
CONTINUE. ALSO WENT ON THE LOW SIDE OF GUIDANCE FOR TUE MAX TEMPS
BASED ON MORE PRECIP AND CLOUD COVER.


DEESE


.LONG TERM /WEDNESDAY THROUGH MONDAY/...

VERY LITTLE CHANGES NEEDED TO THE EXTENDED FORECAST. BY WED MORNING
THE MAIN FRONTAL BOUNDARY WILL HAVE MOVED OFF THE GA/SC COAST WITH
HIGH PRESSURE BUILDING INTO THE REGION FROM THE CENTRAL PLAINS. A
COOLER AIRMASS WILL MOVE IN WITH THIS RIDGE AS WE WILL SE SOME OF
THE COOLEST TEMPS SO FAR THIS SEASON. LOW TEMPS THU MORNING EXPECTED
IN THE 30S AND 40S WITH HIGH TEMPS ONLY GETTING UP INTO THE 60S THU.
THIS COOL AIR REMAINS OVER THE REGION THROUGH THE END OF THE WEEK
AND EVEN GETS REINFORCED FRI/SAT AS ANOTHER STRONGER RIDGE MOVES IN
BEHIND A DRY COLD FRONT FROM THE NORTHERN PLAINS. SOME AREAS ACROSS
EXTREME N GA WILL SE BELOW FREEZING TEMPS SAT MORNING. TEMPS WILL
BEGIN TO REBOUND SUN/MON WILL SEE MAINLY BELOW SEASONAL NORMS WED
THROUGH SAT. NO PRECIP EXPECTED THIS WEEK.

01


&&


.AVIATION...
18Z UPDATE...
PERSISTENT PATCH OF LOW CLOUDS OVER NORTHEAST GEORGIA INCLUDING
AHN FINALLY STARTING TO BREAK UP WITH JUST A SCT VFR DECK FOR MOST
OTHER TAF SITES. SHOULD SEE LOW CLOUDS DEVELOP AGAIN TONIGHT AND
ENCROACH UPON THE SOUTHEAST SECTIONS TONIGHT WITH MCN POSSIBLY
SEEING REDUCED CIGS AND VSBY PRIOR TO DAYBREAK. EXPECTING LOWERING
CIGS ELSEWHERE AS WELL BUT SHOULD REMAIN VFR THROUGH THE PERIOD.
HAVE INCREASED RAIN CHANCES FOR TUE AFTERNOON BUT NOT HIGH ENOUGH
JUST YET FOR INCLUSION IN TAF.

//ATL CONFIDENCE...18Z UPDATE...
MEDIUM ON CIGS TONIGHT.
HIGH REMAINING ELEMENTS.

DEESE

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          54  72  50  65 /   5  30  20   0
ATLANTA         55  70  49  61 /   5  30  20   0
BLAIRSVILLE     45  67  42  54 /   5  30  20   5
CARTERSVILLE    47  70  45  59 /   5  30  10   0
COLUMBUS        59  77  54  69 /   5  20  20   0
GAINESVILLE     53  69  49  60 /   5  30  20   0
MACON           57  75  49  70 /  10  30  20   0
ROME            46  70  44  60 /   5  30  10   5
PEACHTREE CITY  50  72  49  63 /   5  20  20   0
VIDALIA         63  75  55  74 /  30  40  30   0

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...DEESE
LONG TERM....01
AVIATION...DEESE






AREA FORECAST DISCUSSION

NWS MARQUETTE MI

 122 PM EDT MON OCT 21 2013

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 537 AM EDT MON OCT 21 2013

WV IMAGERY AND RUC ANALYSIS INDICATED A RIDGE INTO THE PACIFIC NW
AND A BROAD MID/UPPER LEVEL TROUGH ACROSS THE CNTRL AND EAST CONUS.
A MID LEVEL LOW WAS LOCATED NEAR KINL. A SHORTWAVE TROUGH THAT
BROUGHT THE AREA OF RAIN/SNOW THROUGH UPPER MI WAS LIFTING TO THE
ENE THROUGH CNTRL UPPER MI. AT THE SFC...LOW PRES WAS LOCATED NEAR
WHITE FISH BAY. A TROUGH EXTENDED TO THE NW THROUGH CNTRL LAKE
SUPERIOR AND INTO SRN MANITOBA. RADAR INDICATED THAT THE MAIN AREA
OF PCPN HAD MOVED INTO ERN LAKE SUPERIOR WITH MAINLY
FLURRIES/DRIZZLE TO THE WEST AS 850-500 QVECTOR DIV MOVES IN BEHIND
THE SHRTWV.

TODAY...CONVERGENT LOW LEVEL WRLY WINDS ACROSS LAKE SUPERIOR WITH
850 MB TEMPS FALLING FROM -5C TO -8C AND ABUNDANT MOISTURE BELOW 700
MB SHOULD CONTINUE TO SUPPORT SCT/NMRS SNOW SHOWERS INTO NW UPPER MI
THAT WILL BE MIXED WITH RAIN NEAR THE SHORELINE. THE HIGH RES MODELS
SUGGEST THAT THE SNOW SHOWERS WILL BE MOST PROMINENT IN THE AREA
FROM NEAR ONTONAGON AND ROCKLAND TO TWIN LAKES AND PELKIE.
OTHERWISE...MAINLY DRY WEATHER IS EXPECTED ACROSS THE REST OF THE
CWA WITH SYNOPTIC SCALE SUBSIDENCE TAKING OVER. IT WILL ALSO FEEL
COLDER WITH GUSTY WEST WINDS AND HIGHS FROM THE MID AND UPPER 30S
WEST TO THE MID 40S EAST.

TONIGHT...EXPECT THE SNOW SHOWERS OVER THE WEST TO INCREASE IN
COVERAGE AND INTENSITY AS THE SFC TROUGH EDGES INTO THE AREA. THE
ENHANCED LOW LEVEL CONV WITH THIS FEATURE COMBINED WITH 850 MB TEMPS
AROUND -7C AND THE PROXIMITY OF THE MID LEVEL LOW WILL LEAD TO LAKE
INDUCED CAPE VALUES TO AROUND 500 J/KG. A PERIOD OF MODERATE TO
HEAVY SNOW SHOULD SPREAD INTO NW UPPER MI THIS EVENING AND SAG INTO
IWD BY LATE EVENING AND INTO MARQUETTE COUNTY AFT 06Z. A TRANSITION
TO WIND PARALLEL NNW FLOW LAKE ENHANCED SNOW IS THEN EXPECTED
FOLLOWING PASSAGE OF THE TROUGH. OVERALL SNOW TOTALS IN THE 1 TO 4
INCH RANGE ARE EXPECTED WITH THE GREATEST AMOUNTS IN THE HIGHER
TERRAIN FROM TWIN LAKE SOUTHWARD AND OVER THE HURON MOUNTAINS.
SNOW/WATER RATIOS SHOULD REMAIN RELATIVELY LOW...AOB 10/1...AS THE
STRONGEST UPWARD MOTION REMAINS BELOW THE DGZ AND THE LOWER LEVELS
REMAIN NEAR 0C. AN ADVISORY WAS POSTED FOR THE WRN HALF OF THE CWA
ADJOINING LAKE SUPERIOR.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 350 AM EDT MON OCT 21 2013

A LARGE UPPER TROUGH WILL BE OVER THE GREAT LAKES REGION FOR THIS
WORK WEEK AND LEAD TO BELOW NORMAL TEMPERATURES FOR UPPER MICHIGAN.
THIS COLD AIR WILL ALSO LEAD TO LAKE EFFECT SNOW NEAR LAKE
SUPERIOR. UNCERTAINTY GROWS HEADING INTO THE WEEKEND ON HOW THE
MODELS HANDLE THE UPPER TROUGH SHIFTING EAST OR RE-AMPLIFYING OVER
THE GREAT LAKES.

FOR TUESDAY...THE SURFACE TROUGH THAT WILL BE SWEEPING EAST ACROSS
UPPER MICHIGAN TONIGHT WILL QUICKLY EXIT EASTERN UPPER MICHIGAN ON
TUESDAY MORNING. PRECIPITATION WILL BE ONGOING OVER MUCH OF UPPER
MICHIGAN...ESPECIALLY NEAR LAKE SUPERIOR WITH THE NORTHWEST LAKE
ENHANCED FLOW. MODELS ARE CONTINUING TO SHOW MOISTURE ABOVE 850MB
TO QUICKLY DIMINISH FROM NORTHWEST TO SOUTHEAST ACROSS THE AREA
THROUGH THE DAY ON TUESDAY. THINK THIS DRY AIR ENTRAINMENT WILL
REALLY PUT A CRIMP ON THE SNOWFALL OVER MUCH OF THE CWA EVEN WITH
THE DELTA-T VALUES AROUND 18 AND OVER LAKE INSTABILITY IS AROUND
300-500 J/KG. THUS...WILL SHOW THE HIGHEST POPS TO START TUESDAY AND
QUICKLY DIMINISH VALUES THROUGH THE AFTERNOON HOURS. HELD ON TO THE
HIGHEST POPS OVER THE EAST SINCE THERE MAY BE ENOUGH TIME OVER THE
LAKE TO KEEP SOME SHOWERS AROUND THROUGH THE DAY. EVEN THOUGH THE
DEEPER MOISTURE IS LACKING...WILL SHOW MOSTLY CLOUDY SKIES FOR
THE NORTHWEST WIND FAVORED LOCATIONS INTO THE AFTERNOON.

A WEAK SHORTWAVE SLIDING THROUGH THE AREA ON TUESDAY EVENING WILL
BRING INCREASING LOW LEVEL MOISTURE ACROSS THE LAKE TUESDAY NIGHT
AND THAT WILL CONTINUE INTO WEDNESDAY. 850MB TEMPS ARE STILL AROUND
-7C TUESDAY NIGHT INTO WEDNESDAY...SO THERE IS PLENTY OF OVER THE
LAKE INSTABILITY TO SUPPORT LAKE EFFECT SNOWFALL IN THE NORTHWEST
WIND FAVORED LOCATIONS. EQUILIBRIUM LEVELS AROUND 12KFT WILL
SUPPORT DEEP CLOUD DEPTHS FOR MODERATE LAKE EFFECT SNOW POTENTIAL.
SNOWFALL AMOUNTS WILL LIKELY BE LIMITED BY SNOW RATIOS BEING
AROUND 10-1 DUE TO ONLY THE TOP 5KFT OF THE CLOUD WITHIN THE DGZ AND
THE BEST LAKE FORCING BELOW THAT. THEREFORE...SHOULD SEE SOME
CLUMPING OF THE FLAKES TO SUPPORT THE MORE SYSTEM SNOW LIKE SLR
VALUES...WHICH WILL CUT SNOWFALL AMOUNTS IN HALF FROM WHAT IS
TRADITIONALLY SEEN DURING PURE LES EVENTS. IN ADDITION...WITH
DAYTIME TEMPERATURES TRYING TO RISE INTO THE UPPER 30S OVER THE
EAST...IT TRENDS AWAY FROM THE LOWER 30S GENERALLY NEEDED FOR SNOW
ACCUMULATION. THAT FACTOR IS ALSO INFLUENCED BY THE NORTHWEST WINDS
COMING OFF LAKE SUPERIOR WITH IT/S SURFACE TEMPS AROUND 50
DEGREES...WHICH DOES RAISE THE WETBULB VALUES TO HAVE SOME RAIN
MIXING IN DURING THE DAY WEDNESDAY. THINKING THE BEST OPPORTUNITY
FOR MEASUREABLE SNOW WOULD BE UNDER THE HEAVIEST BANDS AND LATE
TUESDAY NIGHT AND INTO WEDNESDAY MORNING. THEREFORE...HAVE MOST NW
WIND LOCATIONS ONLY SEEING AROUND AN INCH OF SNOW THROUGH WEDNESDAY.
AS WE GET A LITTLE CLOSER WE SHOULD BE ABLE TO PIN DOWN ANY STRONGER
BANDS...WHICH WOULD LOWER TEMPS AND INCREASE SNOWFALL ACCUMULATIONS.

SINCE THE AREA WILL CONTINUE TO BE BETWEEN THE LOW JUST EAST OF
JAMES BAY AND A SERIES OF HIGHS SLIDING SOUTHEAST THROUGH THE
NORTHERN PLAINS...EXPECT THE NORTHWEST WINDS TO CONTINUE THROUGH
THURSDAY NIGHT. 850MB TEMPS LOOK LIKE THERE IS LITTLE VARIABILITY
DURING THAT PERIOD AND WITH MODELS CONTINUING TO SHOW ENOUGH
MOISTURE IN THE LOWER LEVELS...WILL HIGHLIGHT LIKELY POPS IN THE
NORMAL NORTHWEST WIND LOCATIONS THROUGH THE TIME PERIOD. ALTHOUGH
ACCUMULATIONS WON/T BE LARGE...STILL THINK THERE WILL BE SOME AREAS
IN THE WEST AND EAST OF MUNISING THAT WILL HAVE A FEW INCHES OF
SNOW ON THE GROUND BY FRIDAY. BEST OPPORTUNITY FOR ACCUMULATIONS
WILL BE OVER THE WEST...WITH THE EXISTING SNOW ON THE GROUND FROM
TONIGHT.

MODELS REALLY DIFFER ON THE HANDLING OF A SHORTWAVE DIVING
SOUTHEAST TOWARDS THE GREAT LAKES REGION ON FRIDAY AND ACROSS THE
AREA ON SATURDAY OR SUNDAY. THIS SHORTWAVE HAS A LONG JOURNEY AHEAD
OF IT (CURRENTLY NORTH OF HAWAII) AND NEEDS TO ROUND THE RIDGE OVER
THE WEST AND POTENTIALLY MERGE WITH THE ANOTHER WAVE IN NORTHWEST
CANADA. WITH THAT LONG OF A DISTANCE TO TRAVEL...IT/S NOT
SURPRISING THAT THERE ARE DIFFERENCES IN THE GEM/ECMWF/GFS ON THE
SHORTWAVE AND POTENTIAL CLIPPER SYSTEM MOVING THROUGH THE AREA.
12Z GEM/GFS WERE FAIRLY SIMILAR ON THE WAVE AND CLIPPER MOVING
THROUGH ON FRIDAY NIGHT INTO SATURDAY MORNING...WHILE THE 12Z ECMWF
WAS MUCH SLOWER AND KEEPS THE CLIPPER NORTH OF THE AREA (MOVING
THROUGH NORTHERN ONTARIO ON SATURDAY NIGHT). 00Z RUNS HAVE
FLIPPED THE GEM/ECMWF IDEAS WITH THE 00Z GFS STAYING SIMILAR. THESE
DIFFERENCES LEAD TO LITTLE OR NO CONFIDENCE FOR THAT TIME FRAME
OTHER THAN THE BELOW NORMAL HIGH TEMPERATURES WILL CONTINUE.
USING A GENERAL CONSENSUS OF THE MODELS GIVES LOW END CHANCE POPS
FOR THE WEEKEND.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 122 PM EDT MON OCT 21 2013

GUSTY WEST WINDS WILL CONTINUE THIS AFTERNOON AT ALL SITES THIS
AFTERNOON WITH TRANSIENT LAKE EFFECT SNOW SHOWERS AND MVFR
CONDITIONS EXCEPT AT SAW WHICH WILL HAVE A WEST DOWNSLOPE WIND. WITH
ANOTHER DISTURBANCE COMING IN TONIGHT...LAKE EFFECT SNOW SHOWERS
WILL PICK UP IN INTENSITY WITH THE ARRIVAL OF ANOTHER LO PRES TROF
THIS EVENING WILL BRING IFR CONDITIONS/SHSN AT IWD/CMX WHICH WILL
GRADUALLY DIMINISH LATE TONIGHT AND RETURN TO MVFR THERE. AT
SAW...MVFR CONDITIONS WILL MOVE BACK IN THIS EVENING WITH THE
TROUGH.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 401 PM EDT SUN OCT 20 2013

A LOW CENTERED OVER MUCH OF MINNESOTA AN NORTHERN IOWA WILL SLIDE
ACROSS THE UPPER GREAT LAKES TONIGHT THROUGH EARLY MONDAY. EXPECT
THIS LOW TO LIFT SLOWLY INTO QUEBEC MONDAY AFTERNOON WHILE KEEPING A
TROUGH OVER THE UPPER GREAT LAKES THROUGH THURSDAY. A PERIOD OF 35KT
GUSTS WILL BE POSSIBLE OVER S LAKE SUPERIOR STARTING MID MORNING
MONDAY /OUT OF THE W/. A SECOND PUSH OF STRONGER WINDS WILL COME IN
AS THE TROUGH OF LOW PRESSURE WRAPS BACK AROUND...WITH A PERIOD OF
NW GALES OF 35 TO NEAR 40KTS OVER MAINLY CENTRAL AND E LAKE SUPERIOR
MONDAY NIGHT INTO MID TUESDAY. WINDS WILL SLOWLY DIMINISH TUESDAY
AFTERNOON...WITH GUSTS LINGERING IN THE 20 TO 30KT RANGE THROUGH THE
REST OF THE WORK WEEK.

BROAD HIGH PRESSURE OF IS EXPECTED TO BUILD OVER MUCH OF THE PLAINS
STATES BY THURSDAY NIGHT AND SPREAD EASTWARD INTO MUCH OF EASTERN
CONTINENTAL UNITED STATES...WITH A RIDGE OVER THE UPPER GREAT LAKES.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
  WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 8 AM EDT
     TUESDAY FOR MIZ002>004-084.

  WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO 7 AM CDT
     TUESDAY FOR MIZ009.

  WINTER WEATHER ADVISORY FROM 1 AM TO 11 AM EDT TUESDAY FOR
     MIZ005.

LAKE SUPERIOR...
  GALE WARNING UNTIL 11 AM EDT TUESDAY FOR LSZ265>267.

  GALE WARNING FROM 8 PM THIS EVENING TO 11 AM EDT TUESDAY FOR
     LSZ264.

  GALE WARNING UNTIL 8 AM EDT TUESDAY FOR LSZ263.

LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...JLB
LONG TERM...SRF
AVIATION...07
MARINE...KF







AREA FORECAST DISCUSSION...UPDATED

NWS BILLINGS MT

 1122 AM MDT MON OCT 21 2013

.UPDATE...

WE MADE A SECOND MINOR FORECAST UPDATE TO FURTHER INCREASE POPS IN
SOUTHEASTERN MT THIS AFTERNOON IN RESPONSE TO RECENT RADAR TRENDS.
THOSE TRENDS AND RECENT RAP SIMULATIONS SUPPORT POPS OF 90 PERCENT
AROUND BAKER AND POPS AS HIGH AS 50 PERCENT AT MILES CITY. SCHULTZ

&&

.SHORT TERM...VALID FOR TDY AND TUE...

SOMEWHAT UNSTABLE NORTHWEST FLOW WILL CONTINUE ACROSS THE REGION
TODAY. THIS WILL CONTINUE TO PRODUCE SOME LIGHT SCATTERED SHOWERS
ON THE PLAINS AND PERHAPS SOME LIGHT SNOW IN THE HIGHER BIG HORNS.
FORCING DOES NOT LOOK TO ORGANIZED AND IS RELATED TO OVERRUNNING
OF A WEAK BAROCLINIC ZONE IN THE EAST WITH ASSOCIATED WARM AIR
ADVECTION. UPSLOPE INTO NORTH FACING SLOPES OF HIGHER TERRAIN ALSO
PLAYING A ROLE. HOWEVER...MODELS AGREE THAT RIDGING WILL SHIFT
EAST BY EVENING AND KEEP THE BULK OF THIS ACTIVITY IN THE DAKOTAS
BY TUESDAY. I MADE SOME SLIGHT ADJUSTMENTS TO POPS...RAISING THEM
SOME IN THE FALLON COUNTY VICINITY AS THIS PATTERN FAVORS THAT
AREA. MAINLY DRY CONDITIONS AND WARMER TEMPERATURES ARE THEN
EXPECTED FOR TUESDAY. BT

.LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN...

A MAINLY DRY NW FLOW WILL BE OVER THE REGION THROUGH SAT.
CONFIDENCE STARTS TO BREAK DOWN ON SUN WHEN MODELS BRING A STRONG
SHORTWAVE S TOWARD THE AREA FOR A POSSIBLE SYSTEM SUN AND MON.

A WEAK BACKDOOR COLD FRONT WILL MOVE INTO THE AREA ON WED. GFS
SHOWED SOME MOISTURE AND FRONTOGENESIS WITH THE FRONT SO
INTRODUCED SLIGHT CHANCE POPS OVER AREAS E OF KBIL WED MORNING.
AIRMASS WILL DRY OUT IN THE AFTERNOON. DRY WEATHER WILL PREVAIL
THU THROUGH SAT. ON SUN...LATEST GFS BROUGHT A WAVE QUICKLY S INTO
THE AREA WHILE THE ECMWF KEPT THE WAVE TO THE N OF THE CANADIAN
BORDER. KEPT SUN MAINLY DRY AS THE GFS HAS NOT BEEN CONSISTENT IN
BRINGING THE WAVE SO QUICKLY S. BY MON BOTH MODELS HAVE QPF ACROSS
THE ENTIRE AREA...SO HAVE POPS ACROSS THE AREA SUN NIGHT AND MON.
BOTH MODELS DROP 850 MB TEMPERATURES BELOW ZERO DEGREES C DURING
MON SO ANY PRECIPITATION WOULD BE A MIX OF RAIN AND SNOW OR ALL
SNOW. WILL NEED TO WATCH MODEL TRENDS WITH THIS SYSTEM SINCE IT IS
STILL FAR OUT IN TIME. OTHERWISE...TEMPERATURES WILL BE NEAR
SEASONABLE VALUES THROUGH SAT. ARTHUR

&&

.AVIATION...

SCATTERED SHOWERS WILL IMPACT ROUTES EAST OF BILLINGS TODAY...WITH
LOCALIZED MVFR CONDITIONS IN THE HEAVIER SHOWERS. THE BIG HORN
MOUNTAINS WILL LIKELY BE OBSCURED AT TIMES TODAY. CANNOT RULE OUT
AN ISOLATED SHOWER AROUND BILLINGS TODAY...HOWEVER EXPECT TO VFR
CONDITIONS TO PREVAIL. CHURCH

&&

.PRELIMINARY POINT TEMP/POPS...

    TDY TUE     WED     THU     FRI     SAT     SUN
-------------------------------------------------------
BIL 061 039/061 038/057 037/054 040/060 039/060 038/056
    2/N 00/B    00/B    00/U    00/U    00/U    00/U
LVM 058 035/062 035/058 035/061 034/060 035/059 033/053
    1/N 00/N    00/U    00/U    00/U    00/U    01/U
HDN 062 038/062 037/057 035/057 035/061 036/062 035/057
    2/W 00/B    01/B    00/U    00/U    00/U    00/U
MLS 058 039/058 039/055 034/052 034/060 035/058 036/054
    5/W 10/B    02/W    00/U    00/U    00/U    01/U
4BQ 056 038/057 037/055 035/053 035/059 036/059 035/055
    4/W 10/B    02/W    00/B    00/U    00/U    00/U
BHK 051 037/052 036/051 031/048 031/055 033/054 034/055
    9/W 21/E    12/W    00/U    00/U    00/B    01/B
SHR 057 038/059 037/056 034/058 033/061 032/059 034/056
    2/W 00/B    00/B    00/U    00/U    00/U    00/U

&&

.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.

&&

$$
WEATHER.GOV/BILLINGS




AREA FORECAST DISCUSSION

NWS NASHVILLE TN

 317 PM CDT MON OCT 21 2013

.SHORT TERM...SATELLITE PICS SHOWED CLOUDS INCREASING OVER SOUTHERN
MIDDLE TENNESSEE THIS AFTERNOON, AS WELL AS OVER THE EXTREME
NORTHWEST. BIG BULGE OF 300-500MB MOISTURE LIFTING NORTHWARD FROM
GULF COASTAL REGION, AHEAD OF MISSISSIPPI VALLEY SHORTWAVE, WAS
RESPONSIBLE FOR THE INCREASE IN CLOUDS OVER THE SOUTH. MEANWHILE,
A BAND OF INCREASED 850-700MB MOISTURE, IMMEDIATELY AHEAD OF THE
SHORTWAVE WAS PRODUCING THE INCREASED CLOUDS OVER THE EXTREME NORTHWEST.

SURFACE COLD FRONT, THAT WAS PUSHING INTO THE MISSOURI BOOTHEEL AT
MID-AFTERNOON, WAS CREATING A BAND OF SHOWERS, EXTENDING FROM
EASTERN OKLAHOMA AND NORTHWEST ARKANSAS UP ACROSS SOUTHERN PARTS
OF MISSOURI. THIS COLD AND BAND OF RAIN IS EXPECTED TO PUSH EASTWARD
OVERNIGHT INTO MIDDLE TENNESSEE, AND BOTH THE HRRR BRINGS THIS
BAND OF LIGHT RAIN INTO AT LEAST NORTHWESTERN AND NORTH-CENTRAL
PARTS OF OUR FA BY 12Z TUE.

EVEN THOUGH PRECIP TOTALS WILL BE LIGHT WITH THIS NEXT COLD FRONT,
BELIEVE AN INCREASE TO "LIKELY POPS" IS WARRANTED OVER MOST
NORTHERN AREAS TONIGHT AND TUESDAY. WILL GO WITH A CHANCE OF SHOWERS
ELSEWHERE. EXPECT FRONT TO BE NEAR A LAFAYETTE-NASHVILLE-WAYNESBORO
LINE AT 06Z AND THEN PUSH TO THE CUMBERLAND PLATEAY BY 12-14Z.

EXPECT POST-FRONTAL SHOWERS TO END OVER EASTERN AREAS BY 18Z TUE.

SURFACE DEW POINTS DON`T DRY OUT MUCH UNTIL PASSAGE OF ANOTHER COLD
FRONT TUESDAY NIGHT...WHICH WILL SEND DEW POINTS TUMBLING INTO THE
UPPER 20S BY WEDNESDAY AFTERNOON. THERE MAY BE A FEW LIGHT SHOWERS
OVER NORTH-CENTRAL AND NORTHEASTERN PARTS OF THE MID STATE TUESDAY
NIGHT AND WEDNESDAY MORNING AS THIS FRONT PASSES THROUGH. HIGHS ON
WEDNESDAY AREN`T EXPECTED TO EVEN GET OUT OF THE 50S!

STILL LOOKS THE COLD AND DRY CANADIAN AIR MASS THAT COMES IN
WEDNESDAY, WILL KEEP DEW POINTS LOW ENOUGH TO PRODUCE THE
LIKELIHOOD FOR SOME FROST AND FREEZING TEMPERATURES OVER MUCH OF
THE MID STATE DURING LATE WEEK...ESPECIALLY DURING THE EARLY
MORNING HOURS ON FRIDAY AND SATURDAY. A HARD FREEZE (I.E., TEMPS
OF AOB 27 DEGS) MAY EVEN OCCUR ALONG THE CUMBERLAND PLATEAU
SATURDAY MORNING. NASHVILLE MAY EVEN FLIRT WITH THE 32 DEG MARK
THAT SAME MORNING.

.LONG TERM...LOOKS LIKE OUR CHILLY WEATHER PATTERN MAY RELAX JUST
A BIT EARLY NEXT WEEK, WITH UPPER FLOW BECOMING A BIT MORE ZONAL
AND AFTERNOON HIGHS PERHAPS STARTING TO FLIRT WITH THE 70 DEG MARK
OVER SOME SOUTHERN AND WESTERN COUNTIES BY NEXT MONDAY.


&&

.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE      46  62  41  52 /  40  50  10  10
CLARKSVILLE    44  62  38  53 /  70  10  20  05
CROSSVILLE     42  60  39  50 /  20  50  20  10
COLUMBIA       46  65  41  54 /  20  30  10  05
LAWRENCEBURG   44  67  41  55 /  20  20  10  05
WAVERLY        44  63  38  53 /  70  20  10  05

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

19






AREA FORECAST DISCUSSION

NWS HOUSTON/GALVESTON TX

 1215 PM CDT MON OCT 21 2013

.DISCUSSION...
SEE 18Z AVIATION DISCUSSION.

&&

.AVIATION...
GUIDANCE IS NOT IN THE BEST AGREEMENT THIS AFTN. THE RAP IS
AGGRESSIVE WITH RAIN CHANCES THIS AFTN WHILE GLOBAL MODELS LOOK
RATHER BENIGN. WILL CONTINUE TO CARRY VCSH AS PWATS REMAIN AROUND
1.5 INCHES AND LIFT ON THE LEADING EDGE OF A 700 MB TROF AXIS
HEADS THIS WAY. A COLD FRONT WILL CROSS THE AREA LATE TONIGHT BUT
BOTH THE GFS/NAM HINT AT BRIEF IFR CIGS JUST BEFORE SUNRISE. WILL
HINT AT THAT IN THE TAF WITH A SCT008 GROUP. SKIES WILL CLEAR
RAPIDLY TUESDAY MORNING WITH VFR CONDS EXPECTED. WINDS WILL BE
GUSTY IN THE MORNING WITH THE GRADIENT WEAKENING IN THE AFTN. 43

&&

.PREV DISCUSSION... /ISSUED 1000 AM CDT MON OCT 21 2013/

UPDATE...
WIDESPREAD SOUTHERN CWA SHOWERS...WITH OCCASIONAL THUNDER...MOVING
QUICKLY NORTHEAST AT AROUND 40 MPH. THE BULK OF TODAY`S PRECIPITATION
WILL FALL ALONG AND SOUTH OF HIGHWAY 59...OR WHERE THE MOST EFFICIENT
UPPER LEVEL FORCING RESIDES. THE UPPER TEXAS COAST FALLING IN THE
RRQ OF A SOUTHEASTERN U.S. 3H JET WITH A DISTURBANCE RIDING UP AHEAD
OF A CENTRAL TEXAS SHORTWAVE TROUGH. ADDITIONAL CONVECTIVE FOCUS
IS BEING PROVIDED BY A NEAR-STATIONARY WARM FRONTAL BOUNDARY ALONG
THE COAST. THIS EVENING INTO EARLY TUESDAY MORNING`S COLD FRONTAL
PASSAGE ON SCHEDULE TO PASS OVER THE NORTHERN FA TONIGHT...TO THE
COAST BEFORE SUNRISE TOMORROW. PARTIALLY TO MOSTLY OVERCAST WITH
RAIN/ISOLATED STORMS PRIMARILY CONFINED TO SOUTHERN THIRD OF REGION
TODAY...TEMPERATURES WILL CLIMB INTO THE AVERAGE UPPER 70S BY 4 PM.
POST-FRONTAL COOLER AND MUCH DRIER CONDITIONS TOMORROW...INLAND
MORNING MINIMUMS IN THE 50S (60S COAST)...WARMING INTO THE VERY
COMFORTABLE MID 70S. 31

PREV DISCUSSION... /ISSUED 636 AM CDT MON OCT 21 2013/

DISCUSSION...
SEE AVIATION FOR 12Z TAF DISCUSSION

AVIATION...
LIGHT SHRA TO THE WEST OF THE TERMINALS THIS MORNING ASSOCIATED
WITH A WEAK SHORTWAVE DISTURBANCE OVER SAT. EXPECT SHRA COVERAGE
TO INCREASE BY LATE MORNING AS UPPER DISTURBANCE MOVES OVERHEAD. A
COLD FRONT CURRENTLY STRETCHING FROM NEAR FST-SPS-TUL WILL
APPROACH THE REGION TODAY REACHING CLL BY 03Z TUESDAY AND THE
METRO TERMINALS BETWEEN 08-10Z. A BRIEF PERIOD OF MVFR CIGS IS
POSSIBLE AS THE FRONT PASSES THROUGH THE REGION...CLEARING THE
COAST AT THE END OF THE CURRENT TAF PERIOD. 38

PREV DISCUSSION... /ISSUED 442 AM CDT MON OCT 21 2013/

DISCUSSION...
BASED ON 00Z UPPER AIR ANALYSIS AND WATER VAPOR IMAGERY...FIRST
OF A COUPLE OF SHORT WAVE TROUGHS IS AFFECTING SE TX THIS MORNING.
UPWARD VERTICAL MOTION FROM THE FIRST SHORTWAVE IS SUPPORTING
CONVECTION BETWEEN VICTORIA AND WHARTON THIS MORNING ON RADAR
IMAGERY. ALSO GETTING QUITE A BIT OF CONVECTION TO DEVELOP OFF THE
LOWER TX COAST AND S TX. SECOND MORE SIGNIFICANT TROUGH AXIS IS
BACK OVER THE S ROCKIES AND SHOULD BE PUSHING THROUGH LATER TODAY
AND TONIGHT AS IT SHEARS OUT. JET STEAM IS ALSO EXPECTED TO BECOME
MORE FAVORABLE FOR UPWARD MOTION AS IT STRENGTHENS OVER THE MID
SOUTH AND POSITIONS DIVERGENCE OVER SE TX FROM RIGHT ENTRANCE
REGION OF THE JET. EXPECT THERE TO BE SOME ISENTROPIC LIFT AS WELL
FROM DISSIPATING FRONTAL BOUNDARY IN THE GULF. ALL OF THIS SHOULD
SUPPORT SOME RAINFALL ACROSS THE SOUTHERN PORTION OF SE TX AND
ALONG THE COAST. THE 06Z HRRR AND 00Z TX TECH WRF KEEP MOST OF THE
PRECIP OFF THE COAST AND HAVE ORIENTED POPS AS SUCH. POPS MAY BE
ABOUT 10 PERCENT TOO HIGH ACROSS THE BOARD FOR INLAND AREAS BUT
THINK THAT MOST AREAS WILL SEE AT LEAST SOME RAIN...JUST LOWER
AMOUNTS. LOOKS LIKE THE COASTAL COUNTIES WILL LIKELY HAVE MAYBE
0.25-0.5 INCHES OF RAIN. AN 1 INCH TOTALS WILL BE OUT IN THE GULF.
THE REST OF SE TX LIKELY HAVE A TENTH OF AN INCH IF THAT. DESPITE
CLOUD COVER STILL THINK MAX TEMPS IN THE UPPER 70S LOOK GOOD WITH
MOISTURE AND WARM ADVECTION IN PLACE TODAY.

COLD FRONT CURRENTLY WORKING THROUGH OKLA AND W TX WILL PUSH INTO
SE TX TONIGHT AND OFF THE COAST BY 12Z TUE. THIS SHOULD END ANY
RAIN CHANCES FOR SE TX WITH THE BULK OF THE PRECIP IN THE GULF
HEADED TOWARDS N GULF COAST. COLD ADVECTION DURING THE DAY SHOULD
KEEP MAX TEMPS IN THE MID 70S ALONG THE COAST AND LOW 70S FARTHER
INLAND. HIGH PRESSURE WILL BUILD OVER SE TX FOR WED MORNING SO
EXPECT MIN TEMPS BACK IN THE UPPER 40S TO LOW 50S.

NEAR TO BELOW NORMAL TEMPERATURES ARE LIKELY TO CONTINUE THE REST
OF THE WEEK. UPPER LEVEL PATTERN SHOULD BE QUITE AMPLIFIED WITH
LONG WAVE TROUGH OVER THE GREAT LAKES AND NW FLOW ACROSS THE
PLAINS DUE TO RIDGING OVER THE WEST COAST. SHORT WAVE TROUGH STILL
EXPECTED TO IMPACT N TX THROUGH SE TX ON SATURDAY BUT LOOKS MUCH
WEAKER. MOISTURE WILL ALSO BE LIMITED SO BACKED OFF ON POPS SOME
BUT KEPT A PERIOD OF 20 POPS FOR NORTHERN AREAS OF SE TX WHERE
LIFT MAY BE MAXIMIZED. OTHERWISE FORECAST SHOULD BE DRY THROUGH
THE WEEKEND. TEMPERATURES WERE NOT ADJUSTED VERY MUCH BUT DID
TREND TEMPS COOLER FOR THE WEEKEND. ANOTHER AREA OF HIGH PRESSURE
WILL BUILD OVER THE MISS RIVER VALLEY WITH NE/E BOUNDARY LAYER
FLOW OVER SE TX. THIS SHOULD ALLOW FOR COOLER AIR TO FILTER INTO
THE REGION FOR THE WEEKEND. THIS WILL LIKELY KEEP TEMPS NEAR
NORMAL OR EVEN A DEGREE OR TWO BELOW NORMAL. 39

MARINE...
ONSHORE FLOW THIS MORNING WILL PERSIST THROUGH THE DAY AHEAD OF A
COLD FRONT WHICH WILL PUSH OFFSHORE JUST BEFORE DAYBREAK ON
TUESDAY. CAUTION FLAGS WILL BE NEEDED IN THE WAKE OF THE FRONT
WITH ADVISORY CONDITIONS POSSIBLE FOR A BRIEF PERIOD ON TUESDAY.
EXPECT BRISK NORTH AND NORTHEAST WINDS THROUGH THE END OF THE WEEK
WITH CAUTION FLAGS POSSIBLE FOR MOST OF THE WEEK. 38

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      78  53  73  51  77 /  20  20  10  10  10
HOUSTON (IAH)              80  59  75  52  78 /  50  20  10  10  10
GALVESTON (GLS)            79  66  76  62  77 /  90  40  10  10  10

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&

$$

DISCUSSION...31
AVIATION/MARINE...43




AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 1224 PM CDT MON OCT 21 2013

.UPDATE...
ISSUED AT 926 AM CDT MON OCT 21 2013

ADDED SCATTERED FLURRIES TO MUCH OF THE FORECAST AREA TODAY AS
SUBTLE SHORTWAVE TROUGH ROUNDS THE BASE OF THE UPPER LEVEL LOW.
DEPTH OF THE LOW LEVEL CLOUD DECK OFF THE 21.12Z MPX SOUNDING AND
FORECAST RAP SOUNDINGS FOR THIS MORNING INTO THE AFTERNOON HOURS
RANGES FROM 2 TO 6 KFT...IN CONJUNCTION WITH WEAK LIFT...AND LAPSE
RATES WILL BE SUFFICIENTLY STEEP FOR WEAK CONVECTIVE INSTABILITY
SNOW SHOWERS OR FLURRIES TO DEVELOP. UPSTREAM REPORTS FROM THE
TWIN CITIES AREA OF SNOW FLURRIES MATCHES WITH THE WEAK RADAR
RETURNS. SKIES WILL BE OVERCAST FOR MUCH OF THE DAY...AND
TEMPERATURES WILL STRUGGLE TO RISE A LOT. LOWERED HIGHS A BIT TO
ACCOUNT FOR THIS.

&&

.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 259 AM CDT MON OCT 21 2013

THE SURFACE LOW THAT MOVED ACROSS THE REGION SUNDAY IS MOVING
ACROSS NORTHERN LAKE MICHIGAN EARLY THIS MORNING. A TROUGH OF LOW
PRESSURE EXTENDS NORTHWEST FROM THE LOW ACROSS LAKE SUPERIOR INTO
SOUTHERN CANADA. THE SURFACE LOW IS EXPECTED TO KEEP MOVING
NORTHEAST TOWARD HUDSON BAY TODAY AND AS IT DOES...THE TROUGH OF
LOW PRESSURE SHOULD PIVOT AROUND THE BACK SIDE OF THE LOW AND
EXTEND FROM THE LOW BACK TO THE SOUTHWEST ACROSS LAKE SUPERIOR.
THIS IS FARTHER NORTH THAN EARLIER MODELS RUNS WERE
INDICATED...BUT THIS NORTHWARD SHIFT IN POSITION OF THE TROUGH HAS
BEEN A CONSISTENT TREND IN THE MODELS AS WELL. THIS WILL ALL OCCUR
AS THE UPPER LEVEL LOW OVER THE SOUTHWEST CORNER OF ONTARIO STARTS
TO TURN SOUTHEAST AND MOVE TOWARD THE U.P. OF MICHIGAN TODAY. THE
FORCING WITH THE UPPER LEVEL LOW IS EXPECTED TO STAY WELL TO THE
NORTHEAST OF THE AREA WITH ALL THE QG CONVERGENCE STAYING OVER
LAKE SUPERIOR INTO ONTARIO. THE 21.00Z MODELS HAVE ALSO REMAINED
CONSISTENT IN SHOWING THE DEEPEST MOISTURE STAYING ALONG AND NORTH
OF THE SURFACE TROUGH WITH STRONG MID LEVEL DRYING WORKING IN
UNDERNEATH THE UPPER LEVEL LOW. WITH THE SURFACE TROUGH FARTHER TO
THE NORTH AND THE EXPECTED MID LEVEL DRYING...REMOVED THE MENTION
OF ANY PRECIPITATION ACROSS THE AREA FOR TODAY.

THE FOCUS THEN TURNS TO THE NEXT SHORT WAVE TROUGH TO COME DOWN
IN THE NORTHWEST FLOW FOR LATE TONIGHT INTO TUESDAY. THE MODELS
ARE ALL FAIRLY CONSISTENT IN SHOWING THIS WAVE PASSING BY TO THE
SOUTHWEST OF THE AREA BUT CLOSE ENOUGH TO PRODUCE AS MUCH AS 8
PVU/S OF VORTICITY ADVECTION IN THE 500-300 MB LAYER ACROSS THE
SOUTHERN PARTS OF THE FORECAST AREA LATE TONIGHT INTO TUESDAY
MORNING. WEAK TO MODERATE QG CONVERGENCE SHOULD OCCUR IN THE
1000-300 MB LAYER WITH THIS WAVE MAINLY ACROSS NORTHEAST IOWA.
WITH THE SURFACE LOW EXPECTED TO TRACK FROM SOUTHEAST SOUTH
DAKOTA TO NORTHERN MISSOURI TONIGHT THROUGH TUESDAY MORNING...ALL
THE ISENTROPIC UP GLIDE REMAINS CLOSE TO THE SURFACE LOW AND SOUTH
OF THE AREA. ENOUGH FORCING FROM THIS SYSTEM TO JUSTIFY HAVING A
CHANCE OF PRECIPITATION ACROSS THE SOUTH FOR LATE TONIGHT THROUGH
TUESDAY MORNING. SOUNDINGS SUGGEST PLENTY OF ICE WILL BE AVAILABLE
IN THE CLOUDS AND EXPECT ANY PRECIPITATION TYPE ISSUES TO BE
CONTROLLED BY LOW LEVEL TEMPERATURES. SO EXPECT THIS TO MAINLY BE
SNOW POSSIBLY MIXING WITH SOME RAIN TOWARD THE END OF THE EVENT
TUESDAY MORNING.

COULD BE A VERY SIMILAR SYSTEM COMING THROUGH THE NORTHWEST FLOW
FOR WEDNESDAY. THE 21.00Z GFS AND ECMWF BOTH SHOW THE SURFACE LOW
DROPPING SOUTHEAST THROUGH THE MISSOURI RIVER VALLEY AND BRUSHING
THE SOUTHWEST SECTIONS OF THE FORECAST AREA WITH SOME
PRECIPITATION WHILE THE 21.00Z NAM BARELY SHOWS ANYTHING. BASED ON
THE AGREEMENT BETWEEN THE GFS AND ECMWF...ADDED IN A SMALL CHANCE
OF SOME PRECIPITATION ACROSS THE SOUTHWEST PARTS OF THE AREA.

.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 259 AM CDT MON OCT 21 2013

THE NORTHWEST FLOW ALOFT IS EXPECTED TO CONTINUE UNTIL POSSIBLY
VERY LATE IN THE PERIOD WHEN THERE IS SOME SUGGESTION OF THE
WESTERN RIDGE BREAKING DOWN ALLOWING THE FLOW OVER THE UPPER
MIDWEST TO BECOME ZONAL. MODELS ALSO CONTINUE TO SHOW A SYSTEM
COMING ACROSS THE GREAT LAKES REGION IN THE NORTHWEST FLOW IN THE
FRIDAY NIGHT INTO SATURDAY TIME FRAME. HOWEVER...STILL SOME
DIFFERENCES ON THE TRACK OF THE SYSTEM WITH THE GFS BRINGING THE
SURFACE LOW ACROSS WISCONSIN AND SHOWING PRECIPITATION OVER THE
AREA WHILE THE 22.00Z ECMWF TAKES THE SURFACE ACROSS ONTARIO
KEEPING THE AREA DRY. THE 22.00Z GEM LOOKS TO BE MUCH WEAKER WITH
NO SURFACE LOW BUT DOES PRODUCE SOME PRECIPITATION ACROSS
NORTHEAST WISCONSIN. FOR NOW...WILL STAY WITH THE MODEL CONSENSUS
GRIDS AND SHOW SOME SMALL PRECIPITATION CHANCES FOR FRIDAY NIGHT
AND SATURDAY. BELOW TEMPERATURES TO CONTINUE THROUGH THE
PERIOD...BUT SOME WARMING POSSIBLE FOR NEXT WEEKEND...POSSIBLY
APPROACHING 50 ACROSS THE FAR SOUTH.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1131 AM CDT MON OCT 21 2013

ANY HOLES IN THE CLOUD DECK THIS MORNING WILL BECOME BROKEN TO
OVERCAST AS AFTERNOON CUMULUS TAKE OVER. BASES WILL BE
VFR...MAINLY IN THE 4 TO 6 KFT RANGE AND GUSTY NORTHWEST WINDS TO
PERSIST THROUGH EARLY EVENING. CLOUD TRENDS OVERNIGHT ARE LESS
CONFIDENT AS CURRENT SYSTEM PULLS AWAY...AND AHEAD OF THE NEXT
SHORTWAVE TROUGH THAT WILL DROP SOUTHEAST INTO THE AREA. THERE
COULD BE A PERIOD OF CLEAR TO MOSTLY CLEAR SKIES OVERNIGHT BUT
SHOULD QUICKLY FILL IN WITH MID TO HIGH LEVEL CLOUDS FROM THE
NORTHWEST. THE CURRENT FORECAST IS ON THE PESSIMISTIC
SIDE...KEEPING A BROKEN DECK THROUGH THE PERIOD. BY LATER TUESDAY
MORNING...A LOWER BUT STILL VFR DECK COULD DEVELOP. THE
RESTRICTIVE CEILINGS AND CHANCES OF PRECIPITATION TUESDAY MORNING
WILL BE OFF TO THE SOUTH...ACROSS CENTRAL AND EASTERN IOWA.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&

$$

UPDATE.......ZT
SHORT TERM...04
LONG TERM....04
AVIATION.....ZT