Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 10/31/13
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
910 PM CDT WED OCT 30 2013
.UPDATE...
RADAR CONTINUES TO SLOWLY FILL IN AS STRONG STORM SYSTEM LIFTS OUT
OF THE ROCKIES AND INTO THE CENTRAL PLAINS. AS TROUGH APPROACHES
AND HEIGHTS CONTINUE TO FALL...EXPECT PRECIPITATION TO BECOME
HEAVIER WITH TIME. LATEST HRRR MODELS AND INCOMING NAM AGREE WITH
PREVIOUS MODEL RUNS AND POINT TO A FAIRLY RAPID INCREASE IN BOTH
COVERAGE AND INTENSITY OF THE PRECIPITATION AFTER MIDNIGHT. FEEL
THE PLACEMENT OF THE FLASH FLOOD WATCH STILL LOOKS GOOD IN SPITE
OF ACTUAL AMOUNTS STILL NOT VERY IMPRESSIVE AT THIS POINT.
ASSOCIATED FRONTAL BOUNDARY WILL STILL BE LOCATED OVER CENTRAL
OKLAHOMA EARLY THURSDAY MORNING AND SURGE ACROSS THE STATE DURING
THE DAY TAKING THE BULK OF THE PRECIPITATION WITH IT. A PERIOD
OF GUSTY WINDS WINDS SEEMS LIKELY BEFORE AND IMMEDIATELY AFTER
FROPA AND A LAKE WIND ADVISORY WILL LIKELY BE NEEDED AT THAT TIME.
ANY SEVERE THREAT WILL LIKELY BE OVER THE EAST LATER IN THE DAY.
OVERALL THE FORECAST REMAINS IN EXCELLENT SHAPE AND WILL LET IT
RIDE FOR NOW.
&&
.PREV DISCUSSION... /ISSUED 653 PM CDT WED OCT 30 2013/
UPDATE...
UPDATED FOR THE 00Z AVIATION DISCUSSION BELOW.
AVIATION...
WIDESPREAD SHOWERS...WITH SCATTERED THUNDERSTORMS...WILL SPREAD
ACROSS ARKANSAS OVERNIGHT. HAVE FLIGHT CATEGORIES GOING DOWN TO
IFR LEVELS AFTER 08Z-10Z FOR ALL SITES AS A RESULT. THERE SHOULD
BE A BIT OF A BREAK IN SHRA/TSRA ACTIVITY AT NORTHERN SITES FOR A
FEW HOURS THIS EVENING AND TRIED TO TIME THAT IN TAFS...BUT
OTHERWISE SHRA SHOULD BE FAIRLY CONTINUOUS OVER THE NEXT 12-18
HOURS. THUNDER WILL BE MORE INTERMITTENT. STRONGEST THUNDERSTORMS
WILL BE ACROSS CENTRAL AND SOUTHEAST ARKANSAS SO WENT WITH ROUGHLY
5HRS OF PREVAILING THUNDER FOR TERMINALS IN THOSE AREAS...VERSUS
TEMPO THUNDER UP NORTH. A STRONG LOW LEVEL JET WILL SET UP OVER
ARKANSAS TONIGHT AND EARLY TOMORROW MORNING SO LEFT THE LLWS IN
THE TAFS 08Z-14Z UP NORTH...AND 10Z- 16Z IN THE SOUTH.
FINALLY...THE FRONT AND ASSOC CONVECTION SHOULD CLEAR ALL TAF
SITES TO THE EAST BY ROUGHLY 19Z OR SO. VERY GUSTY SOUTHWEST WINDS
WILL FILL IN BEHIND IT...SO WENT WITH 23015G25KT IN AT ALL SITES.
PREV DISCUSSION... /ISSUED 330 PM CDT WED OCT 30 2013/
SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT
PRIMARY FOCUS FOR THIS FCST WL CONT TO BE TNGT AND THU AS THE MUCH
DISCUSSED STORM SYS OVR THE ROCKIES HEADS EWD TNGT AND THU. PLENTY
OF MOISTURE WL CONT TO ADVECT INTO THE MID SOUTH AHEAD OF THIS
SYSTEM...BOTH FM THE GULF...AS WELL AS THE SUB TROPICAL JETSTREAM.
PROGGED PW/S VALUES CONT TO APCH AND/OR EXCEED 2 INCHES OVR MUCH OF
CNTRL AND SRN AR.
BULK OF THE RAINFALL TODAY HAS BEEN ACRS PARTS OF SRN AND NWRN AR.
RAIN COVERAGE WL CONT TO INCRS FM THE W AS THE NGT PROGRESSES...
ALONG WITH EMBEDDED TSRA. LATEST QPF GUIDANCE CONTS TO INDC
GENERALLY TWO TO FOUR INCHES OF RAINFALL THRU THU OVER A LARGE SWATH
OF CNTRL AND SRN AR...WITH ISOLD HIGHER AMTS ACRS SECTIONS OF SWRN
AR...ROUGHLY FM HOT TO TXK. FF WATCH ALREADY IN PLACE...BUT DID OPT
TO ADD THE REST OF THE SERN PART OF THE FA.
AS FAR AS SVR WX POTENTIAL GOES...AN ISOLD STRONG/SVR STORM CANNOT
BE DISCOUNTED OVR SWRN TNGT...BUT NOTHING WIDESPREAD. PARAMETERS ON
THU STILL LOOK TO BE A LOW CAPE/HIGH SHEAR SITUATION AS CLOUDS AND
ONGOING RAINFALL WL LIKELY LIMIT THE AMOUNT OF INSTABILITY.
HOWEVER...THERE COULD BE SOME SVR STORMS TO DVLP THU AFTN ACRS THE
ERN HALF OF AR IF THAT AREA MANAGES TO SEE A BREAK IN THE RAIN AND
CLOUDS. THE PRIMARY THREATS WOULD BE DAMAGING WINDS DUE TO THE
AMOUNT OF WIND ENERGY...AND POSSIBLY AN ISOLD TORNADO OR TWO.
RAIN WL END FROM THE WEST THU AFTN AND THU EVENING AS A CDFNT SWEEPS
THRU...WITH DRIER AND COOLER CONDS TO FOLLOW. ANOTHER UPR TROF WL
SWING THRU THE REGION FRI NGT AND EARLY SAT...BRINGING WITH IT SOME
INCRS IN CLOUDS AND A REINFORCING SHOT OF COOLER AIR.
LONG TERM...SUNDAY THROUGH WEDNESDAY
HIGH PRESSURE WILL BE ACROSS THE AREA TO START THE LONG TERM...BUT
WILL NOT LAST FOR LONG. THE NEXT LARGE UPPER TROUGH WILL MOVE INTO
THE REGION FOR THE MIDDLE OF NEXT WEEK...WITH ANOTHER ROUND OF HEAVY
RAINFALL POSSIBLE...AS MOISTURE VALUES WILL BE HIGH FOR THIS TIME OF
YEAR. FOR NOW...HAVE GONE WITH A BLEND OF MODELS FOR TIMING...WITH
THE EUROPEAN A LITTLE SLOWER THAN THE GFS. TEMPERATURES WILL WARM
INTO THE 60S AHEAD OF THE SYSTEM...WHICH WILL BE SLIGHTLY ABOVE
NORMAL.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 66 73 48 71 / 100 100 10 10
CAMDEN AR 66 75 48 75 / 100 100 10 0
HARRISON AR 63 71 45 68 / 100 80 10 0
HOT SPRINGS AR 67 74 48 73 / 100 90 10 0
LITTLE ROCK AR 67 75 51 72 / 100 90 10 0
MONTICELLO AR 66 74 51 75 / 80 100 20 10
MOUNT IDA AR 66 74 44 72 / 100 80 10 0
MOUNTAIN HOME AR 64 73 44 68 / 100 80 10 0
NEWPORT AR 65 73 51 70 / 100 100 10 10
PINE BLUFF AR 67 74 51 74 / 90 100 10 10
RUSSELLVILLE AR 67 74 45 70 / 100 80 10 0
SEARCY AR 66 74 47 70 / 100 100 10 10
STUTTGART AR 66 74 51 72 / 90 100 10 10
&&
.LZK WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR ARKANSAS-BRADLEY-
CALHOUN-CLARK-CLEBURNE-CLEVELAND-CONWAY-DALLAS-DESHA-DREW-
FAULKNER-GARLAND-GRANT-HOT SPRING-JEFFERSON-JOHNSON-LINCOLN-
LOGAN-LONOKE-MONROE-MONTGOMERY-NEWTON-OUACHITA-PERRY-PIKE-POLK-
POPE-PRAIRIE-PULASKI-SALINE-SCOTT-SEARCY-VAN BUREN-WHITE-
WOODRUFF-YELL.
&&
$$
56
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
852 PM MDT WED OCT 30 2013
.UPDATE...SHOWERS WILL BE EXITING THE FAR EASTERN PLAINS IN THE
NEXT COUPLE HOURS WITH GRADUAL SUBSIDENCE AND DRYING OVER THE
FORECAST AREA. HOWEVER...MODERATE WEST/NORTHWEST OROGRAPHIC FLOW
BUT SHALLOW MOISTURE FIELD WILL KEEP SNOW SHOWERS GOING IN THE
MOUNTAINS. ANOTHER 1-3 INCHES COULD ACCUMULATE MAINLY ON THE
HIGHER RIDGES BY MORNING WITH ONLY SCATTERED LIGHT SHOWERS IN
VALLEYS.
MOUNTAIN TOP STABLE LAYER STRENGTHENS OVERNIGHT AND MODERATE FLOW
ALOFT SHOULD ALLOW MOUNTAIN WAVE TO DEVELOP WITH OCCASIONAL GUSTY
WINDS ALONG THE FRONT RANGE. WILL BEEF UP WINDS A BIT IN THE
MOUNTAIN WAVE WIND FAVORED AREAS NEAR THE FOOTHILLS LATE
TONIGHT/THURSDAY.
&&
.AVIATION...SHOWER THREAT HAS ENDED AND EXPECT GRADUAL CLEARING
OVERNIGHT WITH DOWNSLOPE FLOW DEVELOPING. ANY FOG WOULD BE PATCHY
AT BEST AND WELL NORTH OF KDEN DUE TO INCREASING SOUTH/SOUTHWEST
WINDS. KBJC MAY BEGIN TO GUST TO 20-25 KTS LATE TONIGHT ALREADY...
WITH GUSTY WEST WINDS EXPECTED TO SPREAD INTO KDEN BY 18Z-22Z
THURSDAY WITH STRENGTHENING LEE TROUGHING AND MIXING. COULD SEE
GUSTS AS HIGH AS 30 KTS IF SUFFICIENT MIXING OCCURS. KAPA IS
EXPECTED TO BE ON THE EDGE OF GUSTY WIND FIELD THURSDAY.
&&
.PREV DISCUSSION... /ISSUED 318 PM MDT WED OCT 30 2013/
SHORT TERM...UPPER TROUGH MOVING INTO WESTERN COLORADO AT THIS
TIME WITH SOUTHWEST FLOW ALOFT OVER AREA. MOISTURE AND LIFT
INCREASING ACROSS MOUNTAINS...WITH SOME SHOWERS DEVELOPING ALONG
THE CONTINENTAL DIVIDE. RADAR ALSO INDICATING A BAND OF SHOWERS
ACROSS CENTRAL LARIMER COUNTY...LOOKS TO BE CSI INDUCED AS UPPER
JET NOW NOSING INTO THE MOUNTAINS. TROUGH TO MOVE ACROSS COLORADO
DURING THE EVENING WITH FLOW BECOMING NORTHWEST AROUND MIDNIGHT.
BEST LIFT TO OCCUR THIS EVENING WHEN FLOW IS WEST SOUTHWEST. BEST
OROGRAPHICS OCCUR AFTER MIDNIGHT BUT MID LEVEL ASCENT WEAKENS WITH
INCREASING MID LEVEL SUBSIDENCE. STILL A FAIRLY GOOD SHOT OF SNOW
FOR THE HIGH COUNTRY...THOUGH ACCUMULATIONS WILL BE ON THE LIGHT
SIDE. AMOUNTS OF 2 TO 4 INCHES WILL BE POSSIBLE BY THURSDAY
MORNING. FOOTHILL AREAS COULD ALSO SOME LIGHT ACCUMULATIONS THIS
EVENING AS THE BAND OF PRECIPITATION SHIFTS SOUTH AND EAST...
SHOULD BE LESS THAN 2 INCHES. ACROSS PLAINS...MID LEVEL ASCENT TO
INCREASE THIS EVENING AS TROUGH MOVES OVERHEAD. MODELS STILL
SHOWING BEST CHANCE FOR PRECIPITATION TO BE ACROSS THE PALMER
DIVIDE. PRIMARILY A RAIN/SNOW MIX AS TEMPERATURES TO BE ABOVE
FREEZING. WILL BE COLD ENOUGH FOR THE PRECIPITATION TO BE ALL SNOW
ALONG THE PALMER DIVIDE. LATEST RAP INDICATING THE POTENTIAL FOR
AROUND 2 INCHES IN AN AREA FROM EASTERN DOUGLAS COUNTY ACROSS
NORTHER ELBERT COUNTY. OVERNIGHT...NORTHWEST FLOW ALOFT INCREASES
BEHIND THE EXITING TROUGH. COULD SEE SOME GUSTS TO AROUND 35 MPH
ACROSS THE MOUNTAINS AND HIGHER FOOTHILLS TOWARDS DAYBREAK. ON
THURSDAY...FAIRLY STRONG AND SUBSIDENT NORTHWEST FLOW ALOFT WILL
BE OVER THE AREA. GOOD OROGRAPHICS AND ENOUGH MOISTURE TO GENERATE
SOME LIGHT SNOW...MAINLY NORTHWEST FACING SLOPES. WINDS TO
GRADUALLY INCREASE ACROSS THE MOUNTAINS AND FOOTHILLS ...WITH
POSSIBLE GUSTS TO 45 WINDS BY THE AFTERNOON. ACROSS PLAINS...
COMBINATION OF SUBSIDENCE...MIXING AND INCREASING NORTHWEST
SURFACE GRADIENT WILL CREATE GUSTY WINDS DURING THE AFTERNOON...
MAINLY NORTH AND EAST OF DENVER. SOME GUSTS COULD REACH 40 MPH
OVER THE NORTHEAST CORNER. THERE IS A SLIGHT CHANCE THAT A WEAK
ANTICYCLONE COULD DEVELOP IN THE DENVER AREA WHICH COULD PRODUCE
LIGHT NORTHEAST TO EAST WINDS IN THE DENVER AREA. TEMPERATURE AND
THICKNESS PROGS SUGGEST HIGHS WILL WARM INTO THE UPPER 50S. LATEST
GFS GUIDANCE SEEMS A BIT WARM WHILE THE NAM GUIDANCE APPEARS A BIT
COOL.
LONG TERM...DEEP NORTHWESTERLY FLOW ON THE BACK SIDE OF EXITING
UPPER TROUGH EXPECTED TO PRODUCE GUSTY NORTHWESTERLY SURFACE WINDS
ON THE MTN RIDGES AND NORTHEAST PLAINS DURING THE DAY FRIDAY.
ACCORDING TO NAM...WRF AND GFS CROSS SECTION WIND PROFILES...
STRONGEST WINDS ON THE MTN RIDGE AND UP UP ALONG THE WYOMING/
NEBRASKA BORDER IN THE MORNING...AND ON THE PLAINS LATER IN THE DAY.
PEAK GUSTS IN THE 40-50 MPH HIGHER TERRAIN AND 30-40 MPH ON THE
PLAINS. SOUTHERN PORTIONS OF THE I-25 URBAN CORRIDOR AND WESTERN
VALLEYS WILL ESCAPE MUCH OF THIS WIND. STRONG/GUSTY WINDS DEVELOP
SOON AFTER PASSAGE OF QUICK MOVING SHORTWAVE TROUGH WHICH MODELS
SHOW SWINGING OVER THE WESTERN WYOMING. WEAK POSITIVE QG FORCING AND
SLIGHTLY UNSTABLE LAPSE RATES WITH COOLING ALOFT WILL COMBINE WITH
FAVORABLE OROGRAPHICS TO PRODUCE ANOTHER ROUND OF SNOW SHOWERS IN
THE NORTHERN MTNS THURSDAY NIGHT. NEW SNOW AMOUNTS EXPECTED TO STAY
ON THE LOW SIDE DUE THE RELATIVELY LIMITED MOISTURE. FRIDAY
TEMPERATURES ON THE PLAINS 1-2 DEG C WARMER THAN THE DAY BEFORE WITH
DOWNING FLOW OFF THE FRONT RANGE. TEMPERATURE IN THE HIGH COUNTRY AS
MUCH AS 3-4DEG C WARMER.
FRIDAY NIGHT THROUGH SUNDAY NIGHT...GRADIENT ALOFT SLACKENS AND SO
DO WIND SPEEDS WITH AN BROAD UPPER LEVEL RIDGE PROPAGATING EASTWARD
ACROSS THE ROCKY MOUNTAIN REGION. WARMEST TEMPERATURES ALOFT OVER
COLORADO SATURDAY NIGHT/SUNDAY TIME FRAME. SFC TEMPERATURES RESPOND
WITH A 1-2DEG C WARM UP FRIDAY-SUNDAY. ESSENTIALLY NO CHANCE OF
PRECIP FRIDAY NIGHT THROUGH SUNDAY AFTERNOON...EVEN IN THE HIGH
COUNTRY.
MONDAY-WEDNESDAY TIME FRAME...LONG WAVE PATTERN SHIFTS EASTWARD
ALLOWING THE NEXT UPPER WAVE TO SWING DOWN FROM THE PACIFIC
NORTHWEST. THIS OPEN WAVE DROPS INTO THE UPPER GREAT BASIN SUNDAY
NIGHT. FROM THERE MODELS GENERALLY AGREE IN MOVING THIS SYSTEM EAST-
SOUTHEASTWARD AT BIT OF A SLOWLY PACE THAN WHAT WAS INDICATED BY
EARLIER MODEL RUNS. ALSO LOOKS AS THOUGH THE TROUGH IS DIGGING A BIT
MORE AS IT PASSES OVER COLORADO DURING THE DAY MONDAY. MODELS SHOW A
COLD FRONT SLIDING SOUTH ALONG THE LEE SLOPE OF THE ROCKIES AND INTO
NERN COLORADO BY EARLY ON MONDAY. ASSUMING ALL THIS HAPPENS...SHOULD
SEE A STEADY FALL IN TEMPERATURES ON MONDAY AND A STEADY INCREASE IN
RAIN/SNOW SHOWER DEVELOPMENT IN THE HIGH COUNTRY. PRECIP SHOULD TURN
TO ALL SNOW IN THE HIGH COUNTRY BEFORE NIGHTFALL. ON THE
PLAINS...BASED ON CURRENT MODEL GUIDANCE...SHOWERY PRECIP WOULD
BEGIN LATE IN THE AFTERNOON...AND AS UPSLOPE FLOW STRENGTHENS/
DEEPENS WITH THE TROUGH PASSING OVERHEAD...PRECIP WOULD BECOME MORE
WIDESPREAD AND POSSIBLY BECOME ALL SNOW MONDAY NIGHT INTO TUESDAY.
REALLY TOO EARLY TO KNOW FOR CERTAIN IF ALL THIS WILL OCCUR. FOR NOW
WILL GENERALLY GO WITH 30-40 PCT POPS ON THE PLAINS AND MTN
VALLEYS...AND 40 60 PCT POPS AT HIGHER ELEVATIONS DURING THE TWO DAY
PERIOD. BEYOND TUESDAY...FORECAST LESS CERTAIN. ALL DEPENDS ON HOW
FAST TO THE UPPER TROUGH MOVES OUT. FOR NOW WILL TREND POPS DOWNWARD
AND BEGIN TO RAISE TEMPERATURES.
AVIATION...FINALLY VFR CONDITIONS. NORTHEAST WINDS PREVAILING AT
AREA AIRPORTS WITH SPEEDS AROUND 8 KTS. STILL A CHANCE OF SHOWERS
DEVELOPING BETWEEN 23Z AND 05Z AS UPPER TROUGH MOVES OVERHEAD.
CEILINGS OF AROUND 5000 FEET TO DEVELOP WITH OCCASIONAL CEILINGS
OF AROUND 2500-3000 FEET. BEST CHANCE FOR SHOWERS TO OCCUR AT APA.
THERE IS THE POTENTIAL FOR A MIX OF RAIN AND SNOW WHICH COULD
BRIEFLY CHANGE OVER TO ALL SNOW AFTER 01Z. AT THIS TIME
ACCUMULATIONS ARE NOT EXPECTED. THE THREAT OF PRECIPITATION WILL
END BY 06Z AND WINDS DECREASE AND DRAINAGE FLOW DEVELOPS. VFR
CONDITIONS TO THEN PREVAIL WITH UNLIMITED CEILINGS. THE WINDS
WILL SHIFT TO THE NORTHWEST AROUND 15Z WITH SPEEDS LESS THAN 8
KTS...THEN INCREASING TO AROUND 15 KTS AFTER 20Z. THERE IS A
SLIGHT CHANCE THAT A WEAK ANTICYCLONE WILL DEVELOP BY 18Z WHICH
COULD CREATE LIGHT NORTHEAST WINDS. AT THIS TIME WILL CONTINUE
WITH THE IDEA OF THE NORTHWEST WINDS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BARJENBRUCH
LONG TERM....BAKER
AVIATION...BARJENBRUCH
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
315 PM MDT TUE OCT 29 2013
.SHORT TERM...UPPER LEVEL LOW SPINNING OVER NORTHERN NEVADA THIS
AFTERNOON WITH A STRONG JET ON ITS EAST SIDE STRETCHING FROM
SOUTHWEST AZ NORTHWARD ACROSS THE WESTERN PART OF CO. ON WATER
VAPOR IMAGERY SEE A NICE SIGNAL OF A SHORTWAVE ALSO MOVING ACROSS
NORTHWESTERN AZ. A NICE BAND OF CLOUDINESS AND ECHOES IS
DEVELOPING IN ASSOCIATION WITH THIS FORCING FROM CENTRAL AZ INTO
SW CO AND THERE IS EVEN SOME LIGHTNING SHOWING UP NOW. THIS
FEATURE ALONG WITH THE UPPER LEVEL JET WILL SHIFT OVER THE
FORECAST AREA TONIGHT AS THE MAIN UPPER LEVEL LOW SPLITS WITH THE
NORTHERN PORTION HEADING INTO WY AND THE SOUTHERN PORTION TOWARDS
LAS VEGAS OVERNIGHT. THEN THE ENTIRE TROUGH PASSES ACROSS COLORADO
TOMORROW INTO TOMORROW NIGHT. LATEST RUNS OF SHORTER TERM MODELS
HRRR AND RAP CONTINUE TO EXPAND THE DEVELOPING BAND OF
PRECIPITATION OVERNIGHT AND SHIFTING IT FIRST OVER THE MOUNTAINS
AND THEN THE FOOTHILLS AND ADJACENT PLAINS WITH THE FIRST SLUG OF
MAINLY RAIN SHOWERS INTO THE LOWER ELEVATIONS OF LARIMER COUNTY
BEGINNING BY ABOUT 01 TO 02Z. THEN THE BAND EXPANDS SOUTHWARD INTO
BOULDER COUNTY AND EVENTUALLY TO A LESSER EXTENT JEFFERSON COUNTY.
AGAIN INITIALLY PRECIP WOULD BE MOSTLY RAIN AT LOWER ELEVATIONS THEN
MIXING WITH AND CHANGING TO SNOW WESTERN PORTION OF THE PLAINS.
COULD BE CLOSE TO ADVISORY CRITERIA IN SOME OF THE FOOTHILLS OF
WESTERN BOULDER AND LARIMER COUNTIES BUT NOT ENOUGH CONFIDENCE TO
HOIST ANY KIND OF ADVISORY. AND IN THE MOUNTAINS OROGRAPHIC
COMPONENT IS NOT VERY GOOD SO AMOUNTS UP TO SEVERAL INCHES SHOULD
REMAIN BELOW ANY ADVISORY LIMITS. THERE COULD ALSO BE A BAND OF
MORE RAIN SHOWERS DEVELOPING TOWARDS THE NORTHEAST CORNER OF THE
STATE WITH MORE SCATTERED SHOWER ACTIVITY IN BETWEEN. BEST CHANCE
OF ACCUMULATING SNOWS WOULD BE WEST OF I-25 GENERALLY THOUGH
FARTHER EAST AS WE GET INTO LARIMER COUNTY. STILL A TRICKY CALL
WITHOUT ANY REAL UPSLOPE COMPONENT OF NOTE SO DO NOT WANT TO GET
TOO CARRIED AWAY WITH AMOUNTS BUT DYNAMICS ARE CERTAINLY STRONG
ENOUGH.
FOR TOMORROW AS NOTED TROUGH AXIS MOVES ACROSS AREA LATER IN THE
DAY WHILE AT THE SURFACE FLOW BECOMES GENERALLY NORTHWESTERLY.
HIGHER RESOLUTION MODELS ARE INDICATING A LONGMONT ANTICYCLONE
FLOW WHICH PUSHES MORE NORTHERLY WINDS INTO THE PALMER DIVIDE
REGION AND THERE IS A CHANCE OF SOME SNOW DEVELOPING THERE DURING
THE LATER AFTERNOON HOURS...CLOSER TO ANY UPPER LEVEL FORCING WITH
THE SOUTHERN PART OF THE TROUGH AS IT LIFTS OUT. OTHERWISE MAYBE
SOME RAIN OR SNOW SHOWERS AROUND BUT NOT MUCH EXPECTED ON THE
PLAINS HOWEVER SNOW SHOWERS SHOULD BE LIKELY IN THE MOUNTAINS WITH
BETTER OROGRAPHIC FLOW AND UNSTABLE LAPSE RATES WITH THE CENTER OF
THE TROUGH.
.LONG TERM...AN ELONGATED UPPER LEVEL TROUGH CONTINUES TO MAKE ITS
WAY ACROSS THE CENTRAL ROCKY MOUNTAIN REGION WEDNESDAY NIGHT. QG
LIFT...COLD ADVECTION WILL CONTINUE TO GENERATE SNOW SHOWERS IN THE
HIGH COUNTRY...WITH SOME ADDITIONAL SNOW ACCUM ON WEST-NORTHWEST
FACING MTN SLOPES. ON THE PLAINS...ANOTHER AREA OF QG FORCING
CENTERED OVER SOUTHEAST COLORADO WEDNESDAY EVENING ALSO WARRANTS
MENTIONING A CHANCE OF SNOW IN NORTHEAST COLORADO...PARTICULARLY
ALONG THE PALMER DIVIDE. ANY ACCUMULATION SHOULD BE MINIMAL AT BEST.
OVERNIGHT...UPPER TROUGH PASSES BY AND SOUTHWEST FLOW ALOFT TURNS
NORTHWESTERLY. MODELS SHOW WEST-NORTHWEST WINDS INCREASING IN SPEED
OVER AND ALONG THE EAST FACE OF THE FRONT RANGE LATE WEDNESDAY NIGHT
AND THURSDAY MORNING. CROSS MOUNTAIN WIND COMPONENT AT MTN TOP PEAKS
IN THE 30-45KT THURSDAY MORNING DURING THE PD OF STRONGEST COLD AIR
ADVECTION. DOWNSLOPE SLOPE DRIES OUT PLAINS AIRMASS BUT SAME
NORTHWEST FLOW KEEPS SNOW SHOWERS GOING IN THE HIGH COUNTRY...
MAINLY ALONG AND WEST OF THE CONTINENTAL DIVIDE. HOWEVER...ANY
ADDITIONAL ACCUMULATION SHOULD BE LIGHT WITH DEPTH OF MOISTURE
DECREASING. BY THURSDAY EVENING...MODELS SHOW A WEAK DISTURBANCE
SWINGING DOWN FROM WESTERN WYOMING AND POSSIBLY REGENERATING
SNOWFALL IN THE HIGH COUNTRY. MAY ALSO SEE SOME BANDED LIGHT PRECIP
IN THE FORM OF LIGHT RAIN ON THE PLAINS...AND MOST LIKELY ENDING
BEFORE MORNING.
FRIDAY THROUGH SUNDAY...UPPER TROUGH MARCHES EAST ACROSS THE CENTRAL
ROCKY MTN REGION CAUSING TEMPERATURES TO WARM AND PROVIDING PLENTY
OF CLEAR SKIES. FRIDAY LOOKS QUITE WINDY IN THE NORTHERN FOOTHILLS
AND ACROSS THE NORTHEAST PLAINS. COULD SEE WIND SPEEDS APPROACHING
55 MPH IN THE FOOTHILLS AND 45 MPH ON THE FAR NORTHEAST PLAINS.
SPEEDS WOULD NOT WARRANT THE ISSUANCE OF A HIGH WIND WATCH. SHOULD
SEE STRONG NORTHWEST FLOW ALOFT QUICKLY DECOUPLING FOR THE BOUNDARY
LAYER RESULTING IN A RAPID DROP OFF IN SFC WIND SPEEDS DURING THE
EVENING.
LOOKING AHEAD TO EARLY NEXT WEEK...MEDIUM RANGE MODELS STILL SHOW A
PACIFIC WEATHER SYSTEM/UPPER TROUGH QUICKLY DIVING IN OVER WYOMING
AND NORTHWEST COLORADO ON MONDAY. SYSTEM APPEARS TO BE PACKING A
DECENT AMOUNT OF COLD AIR. SHOULD THIS SYSTEM PROGRESS AS MODELS
INDICATE COULD SEE 24-36 HOURS OF WINTRY WEATHER IN THE HIGH
COUNTRY...AND POSSIBLY ON THE PLAINS. HENCE THE CHANCE POPS FOR
MONDAY AND TUESDAY.
&&
.AVIATION...CLEARING SKIES HAVE GOTTEN CLOSE TO DIA BUT NOW CLOUD
LINE IS SHIFTING SOUTH AGAIN IN NORTHERLY FLOW ON THE BACK SIDE OF
A MODEST DENVER CYCLONE. SO CONTINUE LOW CLOUDS BUT FOG SHOULD
STAY AWAY TONIGHT WHILE EVENTUALLY BAND OF RAIN SHOWERS MOVES ONTO
THE PLAINS CHANGING TO SNOW LATE...MOST LIKELY FOR ANY SNOW AT
BJC.
&&
.HYDROLOGY...MODEST AMOUNTS OF SNOW POSSIBLE INTO THE FOOTHILLS
ESPECIALLY OF BOULDER AND LARIMER COUNTIES OTHERWISE PRECIPITATION
AMOUNTS SHOULD BE GENERALLY BELOW A QUARTER OF AN INCH OR SO
OVERNIGHT AND QUITE A BIT LESS IN MOST AREAS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...SZOKE
LONG TERM....BAKER
AVIATION...SZOKE
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1100 AM MDT TUE OCT 29 2013
.UPDATE...UPPER LEVEL LOW CURRENTLY SPINNING OVER NORTHERN NEVADA
WITH EMBEDDED SHORTWAVES ROTATING AROUND IT AND A STRONG UPPER
LEVEL JET ON ITS EAST SIDE STRETCHING FROM NW COLORADO BACK TO FAR
SOUTHERN CALIFORNIA. THE JET IS SUPPORTING ONE BAND OF
PRECIPITATION NOW OVER WEST-CENTRAL COLORADO THAT IS HEADING MORE
TO THE NORTH OF BOU FORECAST AREA. THE JET CONTINUES TO SHIFT
EASTWARD LATER TODAY AND THEN IS OVER EASTERN COLORADO TONIGHT
WITH THE ASSOCIATED UPPER LEVEL FORCING ALSO SHIFTING EASTWARD. SO
EXPECT CLOUDS TO INCREASE ACROSS THE HIGH COUNTRY THIS AFTERNOON
WITH SNOW SHOWERS GRADUALLY INCREASING LATER IN THE DAY AND THEN
OVERNIGHT AS LOWER LEVEL FLOW BECOMES MORE OROGRAPHICALLY
FAVORABLE.
ON THE PLAINS TRICKY FORECAST FOR CLOUDINESS WITH ERROSION OF
CLOUDS NOW ACROSS WESTERN PORTIONS OF THE PALMER DIVIDE AND AM
UPDATING THE GRIDS RIGHT NOW FOR THIS. SOME ERROSION FROM THE WEST
TOO BUT EXPECT A GRADUALLY INCREASING BUT STILL WEAKISH DENVER
CYCLONE THIS AFTERNOON THAT WILL LIKELY KEEP THE LOWER CLOUDS
SOCKED IN OVER MOST OF THE LOWER PLAINS. VISIBILITIES THOUGH ARE
IMPROVING AND WILL DROP THE FOG ADVISORY FOR THE EASTERN PLAINS.
MAY TWEAK HIGH TEMPERATURES TODAY FOR A LITTLE COOLER NORTH AND
SLIGHTLY MILDER FAR SOUTH ON THE PLAINS.
STILL ASSESSING SITUATION FOR TONIGHT WITH THE OPERATIONAL GFS AND
NAM CONSISTENT IN POINTING TO BEST CHANCE OF A BAND OF PRECIP WITH
SNOW IN THE FOOTHILLS AND SOME RAIN TO SNOW PLAINS MORE FROM
BOULDER COUNTY NORTHWARDS. DOES NOT LOOK LIKE A SIGNIFICANT EVENT
BUT COULD BE A FEW INCHES ESPECIALLY IN THE FOOTHILLS PER THE
LATTEST RAP AND HRRR RUNS.
&&
.AVIATION...AMENDED TAFS FOR IMPROVING VISIBILITIES AND GRADUAL
LIFTING OF CEILINGS TODAY. AT THIS TIME ANY SIGNIFICANT
PRECIPITATION SHOULD STAY NORTH OF DIA TONIGHT.
&&
.HYDROLOGY...COULD BE A FEW INCHES OF SNOW IN THE FOOTHILLS OF
BOULDER AND LARIMER COUNTY OVERNIGHT WITH THE BAND NOTED ABOVE AND
SOME SNOW IN MOUNTAIN LOCATIONS BUT FORCING AND OROGRAPHIC FLOW DO
NOT APPEAR TO BE SIGNIFICANT ENOUGH FOR ANY HIGHLIGHTS AT THIS
TIME.
&&
.PREV DISCUSSION... /ISSUED 834 AM MDT TUE OCT 29 2013/
UPDATE...
SHORT TERM...JUST ISSUED A SHORT FUSED DENSE FOG ADVISORY FOR
PORTIONS OF COLORADO/S NORTHEAST PLAINS. VISIBILITIES HAS
CONTINUED TO VARY FROM 1/4 TO 1 MILE AT SEVERAL LOCALES IN
MORGAN...WASHINGTON...SEDQWICK AND PHILLIPS COUNTIES...AS WELL AS
EASTERN PORTIONS OF ADAMS...ARAPAHOE AND WELD COUNTIES. AND WITH
TEMPERATURES AROUND 0C...GOOD BET THERE/S SOME FREEZING DRIZZLE
AND FREEZING FOG OUT THERE. SO ROAD SURFCES MAY BE ICY IN AREAS.
NO OTHER CHANGES TO THE FORECAST AT THIS TIME.
PREV DISCUSSION... /ISSUED 503 AM MDT TUE OCT 29 2013/
SHORT TERM...ELONGATED UPPER LOW WILL MOVE SLOWLY NORTHEAST
THROUGH TONIGHT...PUSHING AREAS OF LIFT OVER COLORADO. DURING THE
DAY TODAY THERE WILL BE LIFT ASSOCIATED WITH A JET STREAK LIFTING
OUT OF THE TROUGH. THIS IS MOVING OVER RATHER DRY MID LEVEL
AIR...BUT IS HELPING WITH THE SHOWERS ON THE WESTERN COLORADO
BORDER AT THIS TIME. OVERNIGHT TONIGHT THE BAROCLINIC BAND WILL
SHIFT EASTWARD. MODELS INDICATE THAT THIS SHOULD BE DEVELOPING
SOUTHWARD AS IT MOVES THROUGH...WHICH LOOKS GOOD. SHOWERS SHOULD
BE MOVING INTO/DEVELOPING OVER THE MOUNTAINS THIS AFTERNOON...AND
SOME OF THIS SHOULD SURVIVE ONTO THE PLAINS TONIGHT. A LITTLE
COOLING WILL ACCOMPANY THIS...ENOUGH TO CHANGE PRECIP TO ALL SNOW
IN THE MOUNTAINS.
ON THE PLAINS WE HAVE OTHER ISSUES AS THE SATURATED COOL AIR IS
NOT AS SHALLOW AS IT WAS SUPPOSED TO BE. IT GOT UP BETWEEN 9 AND
10 THOUSAND FEET ON THE EAST SLOPE OF THE FRONT RANGE. DESPITE THE
STRONG SW WINDS ABOVE IT THERE IS NOT MUCH SIGN OF
DISPLACEMENT...JUST A FEW HINTS OF WEST WINDS RIGHT AT THE TOP
AROUND THE 9000 FOOT LEVEL. THE LOW LEVEL WINDS IN THE COOL AIR
REMAIN NORTHEAST...INSTEAD OF BECOMING SOUTHEAST AS EXPECTED...AND
THE MOISTURE HAS PUSHED FAR TO THE SOUTH...ALMOST TO OKLAHOMA. SO
WHILE THERE IS DRY AIR AND WIND ABOVE THE CLOUDS...THERE IS NOT
MUCH GOING ON AT LOW LEVELS TO CHANGE THE SITUATION. IN FACT...THE
EASTERLY WINDS WILL LIKELY BE BRINGING IN WARMER BUT STILL
SATURATED AIR WITH HIGHER DEW POINTS DURING THE DAY. THERE MAY YET
BE SOME SCOURING FROM ABOVE BY THIS AFTERNOON...BUT THIS IS
LOOKING PRETTY UNLIKELY IN AREAS ALONG AND NORTH OF INTERSTATE
76...AND QUESTIONABLE EVEN FURTHER SOUTH THOUGH THE ELEVATION OF
THE PALMER DIVIDE MAY HELP. I DROPPED TEMPERATURES ABOUT 5 DEGREES
IN MOST AREAS AND ADDED MORE DRIZZLE WHICH HAS BEEN FAIRLY
WIDESPREAD THOUGH GENERALLY LIGHT. FOR TONIGHT ON THE PLAINS...IT
SHOULD BE WARM ENOUGH FOR RAIN WITH ANY SHOWERS EARLY IN THE
EVENING...AND PROBABLY STAY THAT WAY BUT WITH THE COOLING ALOFT
AND POSSIBLY NOT BEING MUCH ABOVE FREEZING AT THE SURFACE TO BEGIN
WITH THERE DOES APPEAR TO BE SOME CHANCE OF SNOW. WILL MENTION A
MIX FOR NOW.
LONG TERM...ON WEDNESDAY AT 12Z...MODELS HAVE THE UPPER LOW
CENTERED OVER NORTHWESTERN WYOMING WITH THE UPPER TROUGH AXIS
STRETCHING DOWN INTO BAJA CALIFORNIA. THE UPPER TROUGH AXIS IS
PROGGED TO PUSH ACROSS THE FORECAST AREA WEDNESDAY NIGHT. IT IS
OVER THE EASTERN COLORADO BORDER AT 12Z THURSDAY MORNING.
NORTHWESTERLY FLOW ALOFT IS IN PLACE THE REST OF THURSDAY AND
THURSDAY NIGHT. THERE IS UPWARD Q-G VERTICAL VELOCITY PROGGED OVER
THE CWA WEDNESDAY INTO THE EVENING. AFTER 06Z...DOWNWARD MOTION IS
PROGGED. BY THURSDAY AFTERNOON...THE SYNOPTIC SCALE ENERGY IS
BENIGN. THE LOW LEVEL WINDS ARE PROGGED TO BE WEAK UPSLOPE ON
WEDNESDAY AND WEDNESDAY EVENING. THEY BECOME DOWNSLOPING AFTER 06Z
WEDNESDAY NIGHT AND CONTINUE THAT WAY THROUGH THURSDAY NIGHT. FOR
MOISTURE...THERE IS SOME OVER THE PLAINS WEDNESDAY AND WEDNESDAY
NIGHT....BUT MORE OVER THE MOUNTAINS AT THAT TIME. THINGS DRY OUT
OVER MOST OF THE CWA THURSDAY...HOWEVER...THERE IS STILL SOME
MOISTURE STICKING AROUND OVER THE HIGHER MOUNTAINS THURSDAY INTO
FRIDAY MORNING. THERE QPF FIELDS DO SHOW SOME MEASURABLE
PRECIPITATION AROUND THE CWA WEDNESDAY AND WEDNESDAY EVENING.
MOST AREAS HAVE SOME...THE HIGHEST AMOUNTS OVER THE MOUNTAINS.
THERE IS STILL LIMITED AMOUNTS PROGGED OVER THE MOUNTAINS THURSDAY
AND THURSDAY NIGHT. WILL KEEP 30-60% POPS IN THE MOUNTAINS ALL
FOUR PERIODS...AND 0-30%S OVER THE PLAINS FOR WEDNESDAY AND
WEDNESDAY NIGHT. THE PLAINS WILL SEE RAIN FROM THE LATE MORNING
HOURS INTO THE EARLY EVENING ON WEDNESDAY. SNOWFALL AMOUNTS SHOULD
STAY UNDER ADVISORY CRITERIA. FOR TEMPERATURES...WEDNESDAY AND
THURSDAY`S HIGHS LOOK CLOSE TO WHAT TODAY`S WILL BE. FOR THE
LATER DAYS...FRIDAY THROUGH MONDAY...NORTHWESTERLY FLOW ALOFT WILL
CONTINUE INTO FRIDAY NIGHT...THEN AN UPPER RIDGE WILL GET INTO
COLORADO WITH ZONAL FLOW FOR THE CWA SATURDAY. ANOTHER UPPER
TROUGH IS PROGGED INTO THE WESTERN UNITED STATES BY SATURDAY
NIGHT. THE FLOW ALOFT BECOMES SOUTHWESTERLY SUNDAY AND SUNDAY
NIGHT. BY MONDAY AFTERNOON...BOTH THE GFS AND ECMWF HAVE THE UPPER
TROUGH AXIS OVER EASTERN UTAH/WESTERN COLORADO. THERE WILL STILL
BE LIMITED MOISTURE IN THE MOUNTAINS FRIDAY WITH THE
NORTHWESTERLY FLOW ALOFT. THEN IT WILL DRY EVERYWHERE THROUGH
SUNDAY NIGHT...THEN SOME MOISTURE RETURNS TO THE WESTERN CWA
MONDAY WITH THE UPPER TROUGH.
AVIATION...IFR/LIFR CEILINGS WILL LIKELY LAST LONGER THAN
PREVIOUSLY FORECAST...POSSIBLY INTO THE AFTERNOON. SOME
IMPROVEMENT IS EXPECTED LATER IN THE DAY BUT MVFR CONDITIONS ARE
STILL LIKELY...AND MVFR MAY LAST UNTIL THE TROUGH PASSES TONIGHT.
ANY FREEZING DRIZZLE WILL BE VERY LIGHT...PRECIP TYPE EXPECTED TO
BE MAINLY RAIN TONIGHT IN THE DENVER AREA. IF THERE IS SNOW THE
THREAT OF ACCUMULATION ON RUNWAYS IS LESS THAN 10 PERCENT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...SZOKE
LONG TERM....RJK
AVIATION...SZOKE
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1111 PM MDT MON OCT 28 2013
.UPDATE...
ISSUED AT 637 PM MDT MON OCT 28 2013
UPDATED TO FORECAST TO REFLECT THE LATEST SATELLITE TRENDS AND
HIGH-RES MODEL GUIDANCE...A BLEND OF THE HRRR AND WRF. DELAYED THE
PRECIPITATION FOR MOST OF THE NIGHT ALONG THE CONTINENTAL DIVIDE
WITH A RAMP UP OF POPS BY TUESDAY MORNING. BEFORE THAT...JUST
ISOLATED SNOW SHOWERS ARE EXPECTED WITH AN INCH OR TWO POSSIBLE
ACROSS THE PEAKS. REMOVED THE THUNDERSTORM CHANCES ALONG THE
KANSAS BORDER FOR THIS EVENING...LATEST RADAR TRENDS HAVE
THUNDERSTORMS WELL INTO KANSAS...WITH VERY LIMITED MOISTURE AND
FORCING OVER OUR EASTERN COUNTIES.
LOW STRATUS OVER NORTHEAST COLORADO WILL SHIFT SOUTH ACROSS THE
PLAINS THROUGH THE OVERNIGHT. THIS AREA OF MOISTURE IS VERY
SHALLOW WITH PATCHY FOG...AND OVERCAST CONDITIONS ACROSS MUCH OF
THE PLAINS. THERE MAY ALSO BE SOME PATCHY FREEZING DRIZZLE OVER
THE PALMER DIVIDE...AND CAUTION IS ADVISED TOWARD MORNING FOR
PATCHY BLACK ICE. ELSEWHERE...MOISTURE LOOKS TO BE TOO SHALLOW FOR
DRIZZLE. DELAYED WARMING ALONG THE ARKANSAS RIVER VALLEY FOR
TOMORROW MORNING. PUEBLO MAY BE IN THE 30S TO 40S FOR MUCH OF THE
DAY UNTIL MIXING TAKES OVER BY MID AFTERNOON. MOZLEY
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 337 PM MDT MON OCT 28 2013
COOL FRONT HAS SLIPPED DOWN TO THE CO/NM BORDER WITH THE BOUNDARY
JUST N OF THE STATE LINE. NE COLO WAS SOCKED IN WITH LOW CLOUDS AND
THESE CLOUDS WERE JUST MAKING IT INTO EXTREME N AND NE EL PASO COUNTY.
A COUPLE OF WELL DEFINED WIND SHIFT LINES WERE NOTED OVER S EL PASO
AND N PUEBLO COUNTIES. THESE BOUNDARIES WERE ASSOCIATED WITH WIND
SHIFT LINES (NE WINDS VS SE WINDS).
ELSEWHERE...A STRONG UPPER LOW WAS NOTED OVER NEVADA AND WAS MOVING
SLOWLY EAST. QUITE A BIT OF DRY AIR IN THE UPPER LEVELS WAS NOTED IN
ADVANCE OF THIS SYSTEM PER WATER VAP IMGY.
REST OF TODAY INTO TONIGHT...
FIRST CONCERN WILL BE THUNDER. SIMULATIONS CONTINUE TO SHOW TSRA
BREAKING OUT ALONG THE CO/KS BORDER EARLY THIS EVENING. FOR THIS
REASON KEPT VERY SLIGHT POPS ALONG THE BORDER FOR THIS EVENING. I AM
HIGHLY CONFIDENT CONVECTION WILL OCCUR...BUT DO NOT KNOW WHICH SIDE
OF THE BORDER IT WILL INITIATE ON. SPC HAS THE AREA OUTLOOKED WITH A
5% CHANCE OF SVR (HAIL).
2ND CONCERN IS LOW CLOUDS/FOG TONIGHT. VERY CONFIDENT LOW CLOUDS WILL
BE OVER MOST OF THE PLAINS TONIGHT...HOWEVER CONFIDENCE IS NOT TOO
HIGH ON HOW FAR WEST THESE CLOUDS WILL MAKE IT BACK TOWARDS THE
MTNS. LATEST HRRR HAS BECOME A BIT MORE AGGRESSIVE MOVING THE CLOUDS
ALL THE WAY BACK TO THE MTNS. CONCEPTUALLY...THIS LOOKS REALISTIC
AND WILL LIKELY ADD MORE CLOUDS INTO THE NDFD.
OVER THE CONTDVD...MSTR WILL SLOWLY INCREASE TONIGHT...BUT EXPECT
MAINLY SNOW SHOWERS...ESPECIALLY THE SAN JUANS...WITH INSIGNIFICANT
ACCUMS.
SOME FREEZING FOG WILL BE POSSIBLE TONIGHT OVER EL PASO COUNTY.
TUESDAY...
UPPER LOW WILL MOVE CLOSER TO THE REGION AND FLOW ALOFT WILL
INTENSIFY. SFC BOUNDARY ALONG THE CO/NM BORDER WILL LIKELY PUSH
NORTH TOMORROW...BUT HOW FAR N IS THE QUESTION. ATTM...I HAVE THE
BOUNDARY RUNNING ROUGHLY FROM KCOS DOWN TO KSPD BY MID AFTERNOON
TOMORROW. LIKEWISE...GUSTY SW WINDS WILL BE LIKELY OVER THE S TIER
FOR THE FCST AREA...AND WE WILL LIKELY MIX OUT ACROSS EL PASO SO
COULD SEE SOME GUSTY WARM WINDS THIS LOCATION BY MID DAY. IT IS
POSSIBLE KPUB AREA WILL NOT MIX OUT TOMORROW WHILE EL PASO COUNTY
DOES MIX OUT. HIGH TEMPS TOMORROW AT KCOS MAY BE WARMER THAN KPUB.
IF THIS VERIFIES...THEN CURRENT FCST WILL NEED TO BE ADJUSTED BY
LATER SHIFTS.
SNOWS WILL GRADUALLY RAMP UP OVER THE MTNS ALONG THE
CONTDVD...ESPECIALLY LATER TOMORROW AFTERNOON. COULD SEE A COUPLE OF
INCHES OF SNOW...ESPECIALLY ABOVE 10KFT BY LATE TOMORROW AFTERNOON.
IT WILL LIKELY BE WINDY ANY WHERE SOUTH OF THE FRONT...WITH GUSTS TO
25 TO 35 MPH POSSIBLE...AND 40 TO 45 MPH OVER THE HIGHER TRRN.
/HODANISH.
.LONG TERM...(TUESDAY NIGHT THROUGH NEXT MONDAY)
ISSUED AT 337 PM MDT MON OCT 28 2013
UNSETTLED METEOROLOGICAL CONDITIONS ARE ANTICIPATED OVER PORTIONS
OF THE FORECAST DISTRICT FROM TUESDAY NIGHT INTO THURSDAY...ESPECIALLY
OVER THE CENTRAL MOUNTAINS...AS A UPPER SYSTEM IMPACTS THE CWFA
DURING THIS TIME-FRAME. A RETURN TO DRIER AND WARMER CONDITIONS IS
THEN PROJECTED TO RETURN TO THE FORECAST DISTRICT BY THIS WEEKEND.
RECENT LONGER RANGE COMPUTER SIMULATIONS AND FORECAST MODEL
SOUNDINGS SUGGEST THAT DOUBLE-BARRELED CLOSED UPPER LOW INITIALLY
LOCATED OVER NORTHWESTERN WYOMING AND SOUTHERN NEVADA
RESPECTIVELY AT 06Z WEDNESDAY WILL ROTATE INTO AN EASTERN
WYOMING/SOUTHWESTERN COLORADO LOCATION BY 00Z THURSDAY BEFORE
SHIFTING EAST OF THE FORECAST DISTRICT BY 18Z THURSDAY.
THIS SYSTEM WILL BE CAPABLE OF GENERATING SEVERAL INCHES OF
ACCUMULATING SNOW OVER PORTIONS OF THE SOUTHWESTERN AND
ESPECIALLY CENTRAL MOUNTAINS FROM TUESDAY NIGHT INTO THURSDAY
MORNING(I.E. PORTIONS OF PUBLIC ZONES 58/59/60 AND POSSIBLY 66/68
AND 82).
IN ADDITION...EVEN A FEW INCHES OF SNOW WILL BE POSSIBLE OVER
PORTIONS OF EL PASO AND TELLER COUNTIES AS WELL AS POSSIBLY THE
SANGRE DE CRISTO AND WET MOUNTAINS...ESPECIALLY FROM LATER
WEDNESDAY INTO WEDNESDAY NIGHT.
AT THIS TIME IT APPEARS THAT PRIMARILY WINTER WEATHER ADVISORY
SNOW AMOUNTS WILL BE MOST LIKELY WITH THIS EVENT OVER PORTIONS OF
PUBLIC ZONES 58/59/60 AND POSSIBLY 66/68 AND 82 FROM TUESDAY NIGHT
INTO THURSDAY MORNING...ESPECIALLY IF THE 12Z/28TH ECMWF SOLUTION
VERIFIES. ZONE 60 MAY BE THE MOST PRONE TO RECEIVE WINTER STORM
WARNING TOTALS WITH THIS EVENT...ONCE AGAIN IF THE 12Z/28TH ECMWF
IS CORRECT. WFO PUEBLO WILL MONITOR CLOSELY AND ISSUE NEEDED
HIGHLIGHTS AS NEEDED AND AS WE NEAR THIS POTENTIAL EVENT.
GUSTY WINDS(AROUND 50 KNOTS AT TIMES)...PRIMARILY FAVORING HIGHER
TERRAIN LOCATIONS ARE ALSO ANTICIPATED TUESDAY NIGHT AND THEN
AGAIN FROM LATER WEDNESDAY NIGHT INTO THURSDAY NIGHT.
AS TOUCHED UPON BRIEFLY EARLIER...A RETURN TO WARMER AND DRIER
CONDITIONS SHOULD THEN BE EXPERIENCED OVER THE FORECAST DISTRICT
BY THIS WEEKEND AS DRY NORTHWESTERLY TO ZONAL UPPER FLOW DEVELOPS
OVER SOUTHERN COLORADO. FINALLY...WARMEST MAXIMUM TEMPERATURES OF
THE LONGER TERM ARE EXPECTED THIS WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1106 PM MDT MON OCT 28 2013
KALS...VFR CONDITIONS THROUGH THE FORECAST PERIOD. GUSTY SOUTH-
SOUTHWEST WINDS TO NEAR 30 KTS ARE LIKELY TUESDAY AFTERNOON.
SHOWERS ARE FORECAST TO DEVELOP OVER THE MOUNTAINS AND SHIFT EAST
INTO THE SAN LUIS VALLEY BY EARLY EVENING AND COULD POSSIBLY
IMPACT THE TERMINAL.
KCOS...CURRENT OBS INDICATE LOWERING CIGS AND VIS. EXPECT THE
TREND TO CONTINUE THROUGH THE OVERNIGHT PERIOD WITH LOW STRATUS
AND FOG PRODUCING IFR AND PERIODS OF LIFR. CONDITIONS WILL LIKELY
REMAIN DEGRADED THROUGH 15Z WITH IMPROVEMENTS THROUGH 18Z TO VFR.
ALL SHOWER ACTIVITY IS FORECAST TO REMAIN OVER THE RAMPART RANGE
BY LATE AFTERNOON WITH NO IMPACTS EXPECTED AT THIS TIME.
KPUB...CIGS CONTINUE TO LOWER THROUGH THE OVERNIGHT HOURS WITH
CIGS FALLING TO NEAR 800 FEET. FOG WILL REMAIN POSSIBLE AFTER 08Z.
IFR TO LIFR CONDITIONS WILL LIKELY PERSIST THROUGH AROUND 15Z WITH
IMPROVEMENTS THROUGH 20Z TO VFR. MOZLEY
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MOZLEY
AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1024 PM EDT WED OCT 30 2013
.SYNOPSIS...
HIGH PRESSURE OVER THE REGION WILL MOVE OFF THE COAST THIS
EVENING. THE RETURN OF SOUTHERLY WINDS WILL BRING INCREASING
MOISTURE TO THE AREA FRIDAY...AHEAD OF A COLD FRONT. THE COLD
FRONT WILL CROSS THE AREA FRIDAY NIGHT. DRY HIGH PRESSURE WILL
BUILD ACROSS THE REGION FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
FORECAST FOR TONIGHT CONTINUES TO LOOK ON TRACK. MADE A FEW
TWEAKS. SURFACE HIGH PRESSURE WILL GRADUALLY SHIFT OFF THE COAST
AS THE UPPER RIDGE AXIS SHIFTS EAST ACROSS THE CAROLINAS. SATELLITE
IMAGERY INDICATES INCREASING HIGH LEVEL CLOUDINESS FOR OUR REGION
TONIGHT...LEADING TO SLIGHTLY WARMER MIN TEMPS TONIGHT THAN THIS
MORNING...GENERALLY IN THE MID 50S.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
SURFACE HIGH PRESSURE AND THE UPPER LEVEL RIDGE WILL BE OFF THE
COAST THURSDAY. SOUTHWEST FLOW ALOFT WILL PULL MOISTURE ACROSS
THE SOUTHERN TIER OF STATES FROM THE REMNANTS OF THE EAST PACIFIC
TROPICAL STORM RAYMOND. MODELS SHOW PWAT VALUES INCREASING TO
AROUND 2.5 INCHES OVER THE LOWER MISSISSIPPI VALLEY BY THURSDAY.
THIS MOISTURE WILL PROPAGATE EASTWARD INTO OUR AREA THURSDAY NIGHT
INTO FRIDAY NIGHT.
DRY WEATHER WILL CONTINUE THURSDAY. THE AIR MASS WILL REMAIN
STABLE WITH NO DYNAMICS. ABOVE NORMAL TEMPS WILL CONTINUE WITH
HIGHS IN THE UPPER 70S TO LOWER 80S. COULD SEE A CHANCE FOR
SHOWERS THURSDAY NIGHT AS MOISTURE INCREASES. CLOUDS AND WINDS
WILL HOLD OVERNIGHT LOWS IN THE LOW/MID 60S.
SHORT WAVE ENERGY WILL BEGIN AFFECTING THE AREA FRIDAY AHEAD OF
AN APPROACHING COLD FRONT. IN ADDITION TO HIGHER PWAT VALUES...A
40-50 KNOT H850 JET AND UPPER LEVEL DIVERGENCE WILL CROSS THE REGION.
HOWEVER...PRE-FRONTAL HEATING/DESTABILIZATION SHOULD BE LIMITED.
A FEW STRONG/POTENTIALLY SEVERE TSTMS MAY BE POSSIBLE ESPECIALLY
FRIDAY AFTERNOON MAINLY IN THE EAST PART OF THE FA TO THE EAST OF
CAE. POPS IN THE 60 TO 80 PERCENT RANGE FRIDAY INTO FRIDAY NIGHT.
HIGHS FRIDAY ARE EXPECTED TO BE IN THE MID 70S TO AROUND 80 GIVEN
WARM ADVECTION AHEAD OF THE FRONT. LOWS FRIDAY NIGHT WILL RANGE
THROUGH THE 50S AS THE COLD FRONT MOVES THROUGH.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
THE COLD FRONT WILL BE EAST OF THE MIDLANDS AND CSRA BY SATURDAY.
HIGH PRESSURE BEHIND THE FRONT WILL BRING COOLER AND DRIER AIR TO
THE REGION. SKIES CLEARING FOR SATURDAY WITH HIGHS IN THE LOWER
TO THE MIDDLE 70S. CLEAR SATURDAY NIGHT WITH LOWS IN THE 40S. SUNDAY
THROUGH MONDAY ARE THE COOLEST PERIOD WITH HIGHS IN THE MIDDLE 60S
AND LOWS MAINLY IN THE UPPER 30S. THE AIR MASS BEGINS TO MODIFY BY
MONDAY NIGHT AND TUESDAY WITH LOWS IN THE 40S AND THE HIGHS TUESDAY
FROM THE UPPER 60S TO THE LOWER 70S. ANOTHER HIGH AMPLITUDE WEATHER
SYSTEM APPROACHES FROM THE WEST BY THURSDAY WITH INCREASING MOISTURE
AND A SLIGHT CHANCE OF RAIN. HIGHS WEDNESDAY ARE EXPECTED TO BE IN
THE LOWER TO MIDDLE 70S.
&&
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS AT TERMINAL LOCATIONS THROUGH THE EARLY
EVENING...AT LEAST THROUGH 06Z. EXTENSIVE HIGH LEVEL CLOUDS
STREAMING INTO THE REGION FROM THE WEST WILL LIMIT FOG DEVELOPMENT
OVERNIGHT. SO MORE OPTIMISTIC FORECAST WITH REGARDS TO VISIBILITY
RESTRICTIONS TOWARD MORNING. THIS IS SUPPORTED BY LATEST HRRR AND
LAMP GUIDANCE. MVFR FORECAST AT AGS/OGB AFTER 1000Z. PRESSURE
GRADIENT INCREASES ON THURSDAY AHEAD OF AN APPROACHING COLD FRONT
AND WINDS SHOULD PICK UP AFTER 15Z TO AROUND 10 MPH FROM THE
SOUTH.
EXTENDED AVIATION OUTLOOK...EARLY MORNING FOG/STRATUS POSSIBLE
THURSDAY NIGHT INTO FRIDAY MORNING. SHOWERS WITH ASSOCIATED
RESTRICTIONS...ALONG WITH A POSSIBLE THUNDERSTORM...FRIDAY INTO
FRIDAY NIGHT. BREEZY CONDITIONS POSSIBLE SATURDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
720 PM EDT WED OCT 30 2013
.SYNOPSIS...
HIGH PRESSURE OVER THE REGION WILL MOVE OFF THE COAST THIS
EVENING. THE RETURN OF SOUTHERLY WINDS WILL BRING INCREASING
MOISTURE TO THE AREA FRIDAY...AHEAD OF A COLD FRONT. THE COLD
FRONT WILL CROSS THE AREA FRIDAY NIGHT. DRY HIGH PRESSURE WILL
BUILD ACROSS THE REGION FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
FORECAST FOR TONIGHT CONTINUES TO LOOK ON TRACK. MADE A FEW
TWEAKS. SURFACE HIGH PRESSURE WILL GRADUALLY SHIFT OFF THE COAST
AS THE UPPER RIDGE AXIS SHIFTS EAST ACROSS THE CAROLINAS. SATELLITE
IMAGERY INDICATES INCREASING HIGH LEVEL CLOUDINESS FOR OUR REGION
TONIGHT...LEADING TO SLIGHTLY WARMER MIN TEMPS TONIGHT THAN THIS
MORNING...GENERALLY IN THE MID 50S.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
SURFACE HIGH PRESSURE AND THE UPPER LEVEL RIDGE WILL BE OFF THE
COAST THURSDAY. SOUTHWEST FLOW ALOFT WILL PULL MOISTURE ACROSS
THE SOUTHERN TIER OF STATES FROM THE REMNANTS OF THE EAST PACIFIC
TROPICAL STORM RAYMOND. MODELS SHOW PWAT VALUES INCREASING TO
AROUND 2.5 INCHES OVER THE LOWER MISSISSIPPI VALLEY BY THURSDAY.
THIS MOISTURE WILL PROPAGATE EASTWARD INTO OUR AREA THURSDAY NIGHT
INTO FRIDAY NIGHT.
DRY WEATHER WILL CONTINUE THURSDAY. THE AIR MASS WILL REMAIN
STABLE WITH NO DYNAMICS. ABOVE NORMAL TEMPS WILL CONTINUE WITH
HIGHS IN THE UPPER 70S TO LOWER 80S. COULD SEE A CHANCE FOR
SHOWERS THURSDAY NIGHT AS MOISTURE INCREASES. CLOUDS AND WINDS
WILL HOLD OVERNIGHT LOWS IN THE LOW/MID 60S.
SHORT WAVE ENERGY WILL BEGIN AFFECTING THE AREA FRIDAY AHEAD OF
AN APPROACHING COLD FRONT. IN ADDITION TO HIGHER PWAT VALUES...A
40-50 KNOT H850 JET AND UPPER LEVEL DIVERGENCE WILL CROSS THE REGION.
HOWEVER...PRE-FRONTAL HEATING/DESTABILIZATION SHOULD BE LIMITED.
A FEW STRONG/POTENTIALLY SEVERE TSTMS MAY BE POSSIBLE ESPECIALLY
FRIDAY AFTERNOON MAINLY IN THE EAST PART OF THE FA TO THE EAST OF
CAE. POPS IN THE 60 TO 80 PERCENT RANGE FRIDAY INTO FRIDAY NIGHT.
HIGHS FRIDAY ARE EXPECTED TO BE IN THE MID 70S TO AROUND 80 GIVEN
WARM ADVECTION AHEAD OF THE FRONT. LOWS FRIDAY NIGHT WILL RANGE
THROUGH THE 50S AS THE COLD FRONT MOVES THROUGH.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
THE COLD FRONT WILL BE EAST OF THE MIDLANDS AND CSRA BY SATURDAY.
HIGH PRESSURE BEHIND THE FRONT WILL BRING COOLER AND DRIER AIR TO
THE REGION. SKIES CLEARING FOR SATURDAY WITH HIGHS IN THE LOWER
TO THE MIDDLE 70S. CLEAR SATURDAY NIGHT WITH LOWS IN THE 40S. SUNDAY
THROUGH MONDAY ARE THE COOLEST PERIOD WITH HIGHS IN THE MIDDLE 60S
AND LOWS MAINLY IN THE UPPER 30S. THE AIR MASS BEGINS TO MODIFY BY
MONDAY NIGHT AND TUESDAY WITH LOWS IN THE 40S AND THE HIGHS TUESDAY
FROM THE UPPER 60S TO THE LOWER 70S. ANOTHER HIGH AMPLITUDE WEATHER
SYSTEM APPROACHES FROM THE WEST BY THURSDAY WITH INCREASING MOISTURE
AND A SLIGHT CHANCE OF RAIN. HIGHS WEDNESDAY ARE EXPECTED TO BE IN
THE LOWER TO MIDDLE 70S.
&&
.AVIATION /23Z WEDNESDAY THROUGH MONDAY/...
VFR CONDITIONS AT TERMINAL LOCATIONS THROUGH THE EARLY
EVENING...AT LEAST THROUGH 06Z. EXTENSIVE HIGH LEVEL CLOUDS
STREAMING INTO THE REGION FROM THE WEST WILL LIMIT FOG DEVELOPMENT
OVERNIGHT. SO MORE OPTIMISTIC FORECAST WITH REGARDS TO VISIBILITY
RESTRICTIONS TOWARD MORNING. THIS IS SUPPORTED BY LATEST HRRR AND
LAMP GUIDANCE. MVFR FORECAST AT AGS/OGB AFTER 1000Z. PRESSURE
GRADIENT INCREASES ON THURSDAY AHEAD OF AN APPROACHING COLD FRONT
AND WINDS SHOULD PICK UP AFTER 15Z TO AROUND 10 MPH FROM THE
SOUTH.
EXTENDED AVIATION OUTLOOK...EARLY MORNING FOG/STRATUS POSSIBLE
THURSDAY NIGHT INTO FRIDAY MORNING. SHOWERS WITH ASSOCIATED
RESTRICTIONS...ALONG WITH A POSSIBLE THUNDERSTORM...FRIDAY INTO
FRIDAY NIGHT. BREEZY CONDITIONS POSSIBLE SATURDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1231 PM CDT TUE OCT 29 2013
.DISCUSSION...
337 AM CDT
MAIN FORECAST CONCERNS CONTINUE TO BE WITH RAIN POTENTIAL AND MILDER
TEMPERATURES ASSOCIATED WITH A STRONG LOW PRESSURE SYSTEM WHICH WILL
MOVE THROUGH THE UPPER MIDWEST WEDNESDAY NIGHT THROUGH THURSDAY.
SHORT TERM...TODAY THROUGH THURSDAY...
UPPER FLOW PATTERN THIS MORNING IS DOMINATED BY A LARGE CLOSED LOW
OVER THE INTER-MOUNTAIN WEST...WITH SPLIT BUT MAINLY ZONAL FLOW
DOWNSTREAM ACROSS THE EASTERN CONUS. OVERNIGHT WATER VAPOR IMAGERY
DEPICTS A STRONG SHORT WAVE PROPAGATING ACROSS THE CENTRAL PLAINS
AND INTO THE MID-MISSOURI VALLEY...ALONG A LOW LEVEL BAROCLINIC ZONE
ASSOCIATED WITH A STATIONARY SURFACE FRONT WHICH STRETCHES WEST-EAST
FROM KANSAS TO THE OHIO VALLEY. FARTHER NORTH...AN ELONGATED AREA OF
SURFACE HIGH PRESSURE STRETCHED FROM NEAR LAKE WINNIPEG ACROSS THE
NORTHERN GREAT LAKES TO NEW ENGLAND.
THE PLAINS SHORT WAVE WILL CONTINUE TO TRACK EASTWARD ALONG THE
BAROCLINIC ZONE TODAY...WITH WARM ADVECTION/ISENTROPIC UPGLIDE
DEVELOPING ACROSS THE REGION. THE FOCUS FOR STRONGER FORCING AND LOW
LEVEL MOISTURE RETURN WILL REMAIN ACROSS FAR SOUTHERN IA/MISSOURI
AND DOWNSTATE ILLINOIS THROUGH THIS AFTERNOON HOWEVER...WITH MAINLY
JUST MID/HIGH CLOUDINESS EXPECTED ACROSS THE CWA AS LOW LEVEL FLOW
BACKS MORE SOUTHEAST. THIS WILL PULL IN DRIER AIR FROM UPSTREAM...
AS NOTED IN LAST EVENINGS 00Z SOUNDING FROM WILMINGTON OH. SOME
POTENTIAL PROBABLY EXISTS FOR A SPRINKLE OR TWO FROM OUR DEVELOPING
MID-DECK LATER TODAY...THOUGH IT APPEARS THAT ORGANIZED MEASURABLE
PRECIP CHANCES WILL REMAIN PRETTY LOW WITH THE SUITE OF GUIDANCE NOT
PRODUCING QPF. IT DOES APPEAR THAT PRECIP CHANCES WILL INCREASE
SLOWLY FROM THE SOUTH TONIGHT...AS THE ELEVATED BAROCLINIC ZONE
LIFTS SLOWLY NORTH IN RESPONSE TO PERSISTENT WARM ADVECTION ON
SOUTH-SOUTHWEST WINDS. OTHER THAN MOISTURE TRANSPORT/CONVERGENCE
ALONG THE ELEVATED WARM FRONT ON THE NOSE OF A 20-25 KT LOW LEVEL
JET TONIGHT...LITTLE IN THE WAY OF SHORT WAVE SUPPORT IS NOTED AND
HEIGHTS ACTUALLY RISE A BIT WITH WEAK RIDGING DEVELOPING ALOFT.
GUIDANCE DOES BRING SOME LIGHT QPF ACROSS THE SOUTHERN PORTIONS OF
THE CWA OVERNIGHT...THOUGH HAVE GENERALLY LOWERED POPS SIGNIFICANTLY
FROM PREVIOUS FORECAST BASED ON CURRENT GUIDANCE TRENDS.
THE WESTERN TROUGH BEGINS TO OPEN UP AND MOVE EAST WEDNESDAY AND
WEDNESDAY NIGHT...WITH RENEWED SURFACE LOW PRESSURE DEVELOPMENT
ACROSS THE CENTRAL PLAINS. THE LOW WILL LIFT ACROSS THE MID-MISSOURI
VALLEY BY WEDNESDAY EVENING AND INTO THE UPPER MISSISSIPPI VALLEY BY
THURSDAY MORNING...WITH SEVERAL MODELS DEPICTING A SHORT WAVE
APPROACHING THE CWA WEDNESDAY AFTERNOON/EVENING. A MUCH STRONGER
40-50 KT 850 MB JET IS INDICATED WEDNESDAY NIGHT WHICH IMPINGES ON
THE WARM FRONTAL ZONE AS IT LIFTS NORTH...SUGGESTING RAPIDLY
INCREASING POTENTIAL FOR RAIN AND A FEW THUNDERSTORMS BY LATE
WEDNESDAY AND CONTINUING INTO THURSDAY IN THE WARM SECTOR AHEAD OF
THE APPROACHING COLD FRONT. STRONG MOISTURE ADVECTION...PWATS
APPROACHING 1.5 INCHES...AND SURFACE DEW POINT TEMPS IN THE UPPER
50S...SUPPORT FAIRLY HIGH POPS DURING THIS PERIOD.
AS FOR TEMPERATURES...INCREASING CLOUD COVER AND EAST-SOUTHEAST LOW
LEVEL WINDS ARE EXPECTED TO KEEP RISES IN CHECK DESPITE WARMING
ALOFT TODAY. WARMER TEMPS...IN THE 60S...WILL SPREAD NORTH WITH THE
WARM FRONT INTO THE SOUTHERN CWA WEDNESDAY AND ACROSS THE ENTIRE
AREA THURSDAY. RISING TEMPS ARE LIKELY WEDNESDAY NIGHT.
LONG TERM...FRIDAY-MONDAY...
THE LARGE SCALE UPPER TROUGH WILL LINGER ACROSS THE REGION FRIDAY
AND SATURDAY AS ADDITIONAL SHORT WAVE ENERGY DIGS IN FROM THE
NORTHWEST. COOL ADVECTION AND CYCLONIC LOW LEVEL FLOW IN SURFACE
TROUGHING OVER THE LAKES WILL LIKELY SUPPORT CONSIDERABLE CLOUD
COVER INITIALLY...WITH THE POTENTIAL FOR SOME SPRINKLES/SHOWERS
ESPECIALLY FRIDAY NIGHT AND SATURDAY WITH A SECONDARY PUSH OF COLDER
AIR. SURFACE HIGH PRESSURE THEN EVENTUALLY SPREADS ACROSS THE REGION
LATE SATURDAY NIGHT AND SUNDAY. LONG RANGE MODEL SOLUTIONS MOVE THE
HIGH QUICKLY OFF TO THE EAST SUNDAY NIGHT...WITH ANOTHER LOW PASSING
NORTHWEST OF THE FORECAST AREA MONDAY. THIS SETS UP ANOTHER PERIOD
OF SOUTH FLOW AND A RETURN OF RAIN CHANCES ESPECIALLY WEST ON
MONDAY. TEMPS COOL TO THE UPPER 40S/LOW 50S OVER THE WEEKEND BEFORE
MODERATING MONDAY.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* WINDS SOMEWHAT VARIABLE IN DIRECTION BETWEEN ENE TO SSE.
* LOWERING CIG TREND...WITH MVFR LIKELY SOMETIME WEDNESDAY.
BMD
//DISCUSSION...UPDATED 18Z...
EXPECT FAIRLY STEADY STATE CONDITIONS THROUGH THE REST OF TODAY AND
MOST OF TONIGHT...WITH ONLY SOME MINOR UNDULATIONS IN THE EASTERLY
FLOW. LOW PRESSURE WILL CONTINUE TO DEEPEN AND MOVE NORTHEAST ACROSS
THE CENTRAL PLAINS TODAY...WITH A WARM FRONT MOVING INTO CENTRAL
ILLINOIS OVERNIGHT. WARM ADVECTION/ISENTROPIC ASCENT WILL HELP TO
SATURATE THE COLUMN GRADUALLY THROUGH THE PERIOD WITH DRY LOW LEVEL
EASTERLIES HELPING TO HOLD OFF PRECIPITATION. CIGS ARE EXPECTED TO
BUILD DOWN TO MVFR SOMETIME WEDNESDAY MORNING...THOUGH TIMING IS A
BIT UNCERTAIN...AS SOME MODELS HOLD OFF MVFR UNTIL LATE IN THE
MORNING. DESPITE THE PERSISTENT ALBEIT WEAK LOW LEVEL FORCING...
MID/UPPER LEVEL FORCING IS ABSENT AS UPPER RIDGE BUILDS ACROSS THE
REGION WITH PERSISTENT HEIGHT RISES THROUGH MID EVENING. THAT
SAID...A LEAD SHORTWAVE TROUGH WILL EJECT EAST RIDING UP THE RIDGE
OVER THE AREA WEDNESDAY AFTERNOON AND WILL LEAD TO THE BEST CHANCE
FOR PRECIP WITHIN THE CURRENT TAF PERIOD. SOME OF THE MODELS DEVELOP
LIGHT PRECIP OVER THE AREA...AND CONVECTIVE ALLOWING MODELS HINT AT
A FEW SCATTERED SHOWERS. FOR NOW WILL INCLUDE VCSH IN THE
AFTERNOON...BUT IMPACTS AT THE TERMINALS ARE PRETTY UNLIKELY...AND A
VCSH MIGHT EVEN BE A STRETCH. IF CIGS BUILD DOWN LOWER THAN
EXPECTED...THEN DRIZZLE MAY END UP BEING MORE OF A CONCERN TOMORROW
AFTERNOON.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM-HIGH CONFIDENCE IN WIND DIRECTION/SPEED.
* HIGH CONFIDENCE IN GENERAL CIG TRENDS...LOW-MEDIUM CONFIDENCE IN
TIMING CATEGORY CHANGE.
* LOW CONFIDENCE IN PRECIP IMPACTING TERMINALS WEDNESDAY.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...SHRA W/ CHANCE OF TSRA.
THURSDAY...SHRA W/ CHANCE OF TSRA.
FRIDAY...CHANCE OF SHRA EARLY...OTHERWISE VFR.
SATURDAY...CHANCE OF SHRA...OTHERWISE VFR.
SUNDAY...VFR.
MONDAY...SLIGHT CHANCE OF SHRA...OTHERWISE VFR.
RODRIGUEZ
&&
.MARINE...
418 AM CDT
MAIN FORECAST CONCERN IS WITH A SYSTEM TO APPROACH THE GREAT LAKES
REGION WEDNESDAY NIGHT INTO THURSDAY...WITH GALE FORCE GUSTS TO 35
KT POSSIBLE ACROSS THE WHOLE LAKE DURING THIS PERIOD.
THE CENTER OF LARGE HIGH PRESSURE SPANNING SOUTHERN CANADA AND THE
UPPER MIDWEST WILL SHIFT SOUTHEAST THROUGH THE GREAT LAKES REGION
TO THE ATLANTIC COAST TODAY...WHILE A TROUGH OF LOW PRESSURE OVER
THE SOUTHERN PLAINS REMAINS SITUATED. AS THIS OCCURS...EXPECT EAST
WINDS TO DIMINISH TO 10 TO 15 KT WHILE TURNING TO THE SOUTHEAST
TODAY AND TONIGHT. DESPITE THIS TROUGH OF LOW PRESSURE DEEPENING
AS IT SLOWLY LIFTS NORTHEAST THROUGH THE CENTRAL PLAINS TONIGHT
INTO WEDNESDAY...A FAIRLY RELAXED GRADIENT OVER THE LAKE WILL HELP
LIGHT SOUTHEAST WINDS TO PERSIST DURING THE DAY WEDNESDAY.
ALTHOUGH THIS LOW WILL CONTINUE DEEPENING AS IT LIFTS TO THE UPPER
MIDWEST WEDNESDAY NIGHT AND AS THIS OCCURS...EXPECT THESE
SOUTHEAST WINDS TO BECOME SOUTH AND INCREASE TO 30KT. ONCE
AGAIN...ITS DURING THE WEDNESDAY NIGHT AND THURSDAY TIME FRAME
WHEN GALE FORCE GUSTS ARE POSSIBLE. WILL NEED TO MONITOR THIS TIME
FRAME AND IF INCREASING TRENDS OCCUR OVER THE NEXT FORECAST
RUNS...POSSIBLE GALES WILL NOT BE OUT OF THE QUESTION. THIS LOW
WILL MOVE EAST INTO SOUTHEAST ONTARIO AND QUEBEC THURSDAY NIGHT
INTO FRIDAY BEFORE EXITING TO THE NORTHEAST FRIDAY NIGHT. EXPECT
SOUTHWEST WINDS TO BECOME WEST STILL HOLDING AT 30 KT THROUGH
EARLY FRIDAY...BEFORE DIMINISHING LATER THAT DAY.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 3 PM
TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
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Area Forecast Discussion
National Weather Service Lincoln IL
1216 PM CDT Tue Oct 29 2013
.DISCUSSION...
ISSUED 955 AM CDT Tue Oct 29 2013
Large rain shield advancing eastward across Missouri, but the
eastern edge is being chewed up by the dry air that is currently
in place over Illinois. Initial radar returns will go toward
moistening up the column from the top down, so it will probably be
toward early afternoon before any steadier rains arrive in our
forecast area, and then it will be most likely south of I-72. Have
left slight chance PoP`s in across the northeast third of the CWA
for now, although latest guidance from the NAM/RAP/HRRR models is
indicating that any rain today will likely remain to the south,
and would probably hold off until mid or late afternoon if it does
manage to get that far north.
Have sent some updated zones/grids to freshen up the temperature
and rain trends, although no significant changes were made.
Geelhart
&&
.AVIATION...
ISSUED 1215 PM CDT Tue Oct 29 2013
Incoming rain shield has been eroding on the leading edge due to
the dry air currently in place, so will continue to limit any rain
mention to VCSH at KPIA/KSPI and keep eastern TAFs dry for now.
Main concern will be tonight, as ceilings lower below 3000 feet
this evening from south to north, then are likely to drop to IFR
range after 06Z, with the highest chances of this occurring at
KSPI and KPIA. Drier air aloft will limit overnight precip chances
to mainly some drizzle or very light showers. Ceilings should
begin to come up Wednesday morning as a warm front lifts northward
through central Illinois. Will maintain MVFR ceilings through the
morning, although areas from KSPI-KCMI may see them lift above
3000 feet by late morning.
Geelhart
&&
.PREV DISCUSSION...
ISSUED 254 AM CDT Tue Oct 29 2013
Main challenges with this forecast package are rain chances today
through Thursday and the potential for severe weather Thursday
afternoon.
Current upper air pattern features the main branch of the polar
jet flowing well to the north across central and eastern Canada.
Further southwest, a deep closed low has become cut-off from the
flow and is now meandering eastward across the Great Basin. This
low will be the dominant weather-maker across central Illinois for
the next several days as it slowly makes its way eastward.
SHORT TERM...Today through Thursday
Weak frontal boundary that dropped into the area yesterday
afternoon has now become stationary just north of the Ohio River.
To the north of the front, a dry E/NE flow prevails across central
Illinois early this morning, with 07z/2am dewpoints mainly in the
30s. This dry airmass will inhibit the eastward spread of precip
currently developing ahead of a weak short-wave trough over the
Plains. The onset of precip has been gradually delayed with each
model run over the past couple of days, with the 00z Oct 29 suite
now keeping the KILX CWA dry until afternoon. HRRR suggests light
showers may arrive in the Winchester/Jacksonville area around
midday, then will spread eastward to the Indiana border toward
evening. Will therefore go with a dry forecast this morning, then
will focus highest POPs across the southern CWA in closer proximity
to the stalled front this afternoon. Further north toward the I-74
corridor, little or no precip is expected today. Once this initial
wave passes, short-wave ridging in its wake will keep rain
chances low tonight. Despite lack of upper forcing, moistening
airmass and presence of surface boundary support low chance POPs
through the night.
As Great Basin upper low begins to approach from the west, surface
front will get nudged northward on Wednesday. Thanks to southerly
winds south of the boundary, afternoon high temperatures will rise
into the upper 60s and lower 70s. In addition, showers and
thunderstorms will become more widespread during the afternoon,
particularly along/west of the Illinois River.
Main rain/convective event is still slated for Wednesday night
into Thursday as strong cold front approaches from the west.
Models are generally in good agreement with their mass fields, but
still have some minor differences in QPF. As boundary nears,
copious amounts of moisture will advect northward from the Gulf of
Mexico, with precipitable water values nearing 1.50 on Thursday.
Given ample moisture, strong upper dynamics, and presence of
approaching cold front, will carry likely to categorical POPs
across the board Wednesday night and Thursday. Total rainfall with
this system will generally range from 1 to 1.50, with isolated
higher amounts within stronger storms.
Strong to potentially severe thunderstorms will be possible
Thursday afternoon as the front swings through the region:
however, details remain uncertain at this point. NAM/GFS forecast
soundings indicate a low CAPE/high shear environment in the warm
sector ahead of the front, with the greatest instability focused
further southeast from the Ohio River Valley to the western Gulf
Coast. Latest DAY 3 convective outlook from SPC highlights this
area for potential severe, but can not rule out a few strong
storms with damaging wind gusts further north across east-central
and southeast Illinois, particularly given impressive 0-6km bulk
shear values of 70 to 75kt.
LONG TERM...Friday through Monday
Cooler and drier weather will return by the end of the week, as
upper trough digs across the Great Lakes. GFS/ECMWF both suggest
clouds and a few showers will be possible across northeast
Illinois into north-central Indiana Friday into Saturday: however,
think these will remain northeast of central Illinois. High
pressure building into the Midwest will be the dominant weather
feature in the extended, resulting in cool highs in the 50s Friday
through Monday. Next chance for rain will likely hold off until
Tuesday when another system approaches from the west.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1104 AM CDT TUE OCT 29 2013
.DISCUSSION...
337 AM CDT
MAIN FORECAST CONCERNS CONTINUE TO BE WITH RAIN POTENTIAL AND MILDER
TEMPERATURES ASSOCIATED WITH A STRONG LOW PRESSURE SYSTEM WHICH WILL
MOVE THROUGH THE UPPER MIDWEST WEDNESDAY NIGHT THROUGH THURSDAY.
SHORT TERM...TODAY THROUGH THURSDAY...
UPPER FLOW PATTERN THIS MORNING IS DOMINATED BY A LARGE CLOSED LOW
OVER THE INTER-MOUNTAIN WEST...WITH SPLIT BUT MAINLY ZONAL FLOW
DOWNSTREAM ACROSS THE EASTERN CONUS. OVERNIGHT WATER VAPOR IMAGERY
DEPICTS A STRONG SHORT WAVE PROPAGATING ACROSS THE CENTRAL PLAINS
AND INTO THE MID-MISSOURI VALLEY...ALONG A LOW LEVEL BAROCLINIC ZONE
ASSOCIATED WITH A STATIONARY SURFACE FRONT WHICH STRETCHES WEST-EAST
FROM KANSAS TO THE OHIO VALLEY. FARTHER NORTH...AN ELONGATED AREA OF
SURFACE HIGH PRESSURE STRETCHED FROM NEAR LAKE WINNIPEG ACROSS THE
NORTHERN GREAT LAKES TO NEW ENGLAND.
THE PLAINS SHORT WAVE WILL CONTINUE TO TRACK EASTWARD ALONG THE
BAROCLINIC ZONE TODAY...WITH WARM ADVECTION/ISENTROPIC UPGLIDE
DEVELOPING ACROSS THE REGION. THE FOCUS FOR STRONGER FORCING AND LOW
LEVEL MOISTURE RETURN WILL REMAIN ACROSS FAR SOUTHERN IA/MISSOURI
AND DOWNSTATE ILLINOIS THROUGH THIS AFTERNOON HOWEVER...WITH MAINLY
JUST MID/HIGH CLOUDINESS EXPECTED ACROSS THE CWA AS LOW LEVEL FLOW
BACKS MORE SOUTHEAST. THIS WILL PULL IN DRIER AIR FROM UPSTREAM...
AS NOTED IN LAST EVENINGS 00Z SOUNDING FROM WILMINGTON OH. SOME
POTENTIAL PROBABLY EXISTS FOR A SPRINKLE OR TWO FROM OUR DEVELOPING
MID-DECK LATER TODAY...THOUGH IT APPEARS THAT ORGANIZED MEASURABLE
PRECIP CHANCES WILL REMAIN PRETTY LOW WITH THE SUITE OF GUIDANCE NOT
PRODUCING QPF. IT DOES APPEAR THAT PRECIP CHANCES WILL INCREASE
SLOWLY FROM THE SOUTH TONIGHT...AS THE ELEVATED BAROCLINIC ZONE
LIFTS SLOWLY NORTH IN RESPONSE TO PERSISTENT WARM ADVECTION ON
SOUTH-SOUTHWEST WINDS. OTHER THAN MOISTURE TRANSPORT/CONVERGENCE
ALONG THE ELEVATED WARM FRONT ON THE NOSE OF A 20-25 KT LOW LEVEL
JET TONIGHT...LITTLE IN THE WAY OF SHORT WAVE SUPPORT IS NOTED AND
HEIGHTS ACTUALLY RISE A BIT WITH WEAK RIDGING DEVELOPING ALOFT.
GUIDANCE DOES BRING SOME LIGHT QPF ACROSS THE SOUTHERN PORTIONS OF
THE CWA OVERNIGHT...THOUGH HAVE GENERALLY LOWERED POPS SIGNIFICANTLY
FROM PREVIOUS FORECAST BASED ON CURRENT GUIDANCE TRENDS.
THE WESTERN TROUGH BEGINS TO OPEN UP AND MOVE EAST WEDNESDAY AND
WEDNESDAY NIGHT...WITH RENEWED SURFACE LOW PRESSURE DEVELOPMENT
ACROSS THE CENTRAL PLAINS. THE LOW WILL LIFT ACROSS THE MID-MISSOURI
VALLEY BY WEDNESDAY EVENING AND INTO THE UPPER MISSISSIPPI VALLEY BY
THURSDAY MORNING...WITH SEVERAL MODELS DEPICTING A SHORT WAVE
APPROACHING THE CWA WEDNESDAY AFTERNOON/EVENING. A MUCH STRONGER
40-50 KT 850 MB JET IS INDICATED WEDNESDAY NIGHT WHICH IMPINGES ON
THE WARM FRONTAL ZONE AS IT LIFTS NORTH...SUGGESTING RAPIDLY
INCREASING POTENTIAL FOR RAIN AND A FEW THUNDERSTORMS BY LATE
WEDNESDAY AND CONTINUING INTO THURSDAY IN THE WARM SECTOR AHEAD OF
THE APPROACHING COLD FRONT. STRONG MOISTURE ADVECTION...PWATS
APPROACHING 1.5 INCHES...AND SURFACE DEW POINT TEMPS IN THE UPPER
50S...SUPPORT FAIRLY HIGH POPS DURING THIS PERIOD.
AS FOR TEMPERATURES...INCREASING CLOUD COVER AND EAST-SOUTHEAST LOW
LEVEL WINDS ARE EXPECTED TO KEEP RISES IN CHECK DESPITE WARMING
ALOFT TODAY. WARMER TEMPS...IN THE 60S...WILL SPREAD NORTH WITH THE
WARM FRONT INTO THE SOUTHERN CWA WEDNESDAY AND ACROSS THE ENTIRE
AREA THURSDAY. RISING TEMPS ARE LIKELY WEDNESDAY NIGHT.
LONG TERM...FRIDAY-MONDAY...
THE LARGE SCALE UPPER TROUGH WILL LINGER ACROSS THE REGION FRIDAY
AND SATURDAY AS ADDITIONAL SHORT WAVE ENERGY DIGS IN FROM THE
NORTHWEST. COOL ADVECTION AND CYCLONIC LOW LEVEL FLOW IN SURFACE
TROUGHING OVER THE LAKES WILL LIKELY SUPPORT CONSIDERABLE CLOUD
COVER INITIALLY...WITH THE POTENTIAL FOR SOME SPRINKLES/SHOWERS
ESPECIALLY FRIDAY NIGHT AND SATURDAY WITH A SECONDARY PUSH OF COLDER
AIR. SURFACE HIGH PRESSURE THEN EVENTUALLY SPREADS ACROSS THE REGION
LATE SATURDAY NIGHT AND SUNDAY. LONG RANGE MODEL SOLUTIONS MOVE THE
HIGH QUICKLY OFF TO THE EAST SUNDAY NIGHT...WITH ANOTHER LOW PASSING
NORTHWEST OF THE FORECAST AREA MONDAY. THIS SETS UP ANOTHER PERIOD
OF SOUTH FLOW AND A RETURN OF RAIN CHANCES ESPECIALLY WEST ON
MONDAY. TEMPS COOL TO THE UPPER 40S/LOW 50S OVER THE WEEKEND BEFORE
MODERATING MONDAY.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* MVFR CONDITIONS RETURN EARLY WEDNESDAY MORNING.
* -SHRA MOVING NEAR THE TERMINALS TONIGHT.
RODRIGUEZ/BMD
//DISCUSSION...UPDATED 12Z...
MVFR STRATUS PERSISTING PRIMARILY OVER ORD EARLY THIS
MORNING...WITH ORD BEING IN A FAVORABLE AXIS FOR PERSISTENT
DEVELOPMENT. THESE CONDITIONS WILL REMAIN OVER THE NEXT 2-3 HOURS
BEFORE THESE CEILINGS LIFT NORTH OF THE TERMINALS. SHOULD ONLY
AFFECT ORD...BUT COULD COME CLOSE TO DPA AS THIS LIFTS NORTHWARD.
CEILINGS ARE CURRENTLY HOLDING AT 1500FT...WITH THEM NOT
ANTICIPATED TO LOWER ANY FURTHER. WITH THE DEPARTURE OF THIS LOW
STRATUS...ONLY MID/HIGH LEVEL CLOUD COVER EXPECTED TODAY INTO
TONIGHT AS MOISTURE STREAMS OUT AHEAD OF AN APPROACHING SYSTEM TO
THE WEST. SEVERAL MID LEVEL DISTURBANCES WILL MOVE ACROSS THE
REGION THIS EVENING WITH THE LEADING EDGE OF THE CURRENT PRECIP
SHIELD OVER THE CENTRAL PLAINS WORKING ITS WAY TOWARDS THE
TERMINALS TONIGHT. ALTHOUGH OUTSIDE OF SOME SCT LIGHT SHOWERS NEAR
RFD...IT DOES APPEAR AS IF BETTER FORCING WILL REMAIN TO THE SOUTH
OF THE TERMINALS AND LIKEWISE PRECIP AXIS. ALTHOUGH FURTHER
SATURATION IS EXPECTED OVERNIGHT INTO EARLY WEDNESDAY MORNING WITH
CEILINGS LOWERING...AND MVFR CONDITIONS ONCE AGAIN RETURNING OVER
THE TERMINALS.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH CONFIDENCE WITH CEILINGS/TRENDS TODAY...MEDIUM CONFIDENCE
EARLY WEDNESDAY MORNING.
* HIGH CONFIDENCE WITH WIND DIRECTION...LOW CONFIDENCE IN GUSTS.
* LOW MEDIUM CONFIDENCE WITH -SHRA/TRENDS TONIGHT.
RODRIGUEZ/BMD
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...SHRA W/ CHANCE OF TSRA.
THURSDAY...SHRA W/ CHANCE OF TSRA.
FRIDAY...CHANCE OF SHRA EARLY...OTHERWISE VFR.
SATURDAY...CHANCE OF SHRA...OTHERWISE VFR.
SUNDAY...VFR.
MONDAY...SLIGHT CHANCE OF SHRA...OTHERWISE VFR.
RODRIGUEZ
&&
.MARINE...
418 AM CDT
MAIN FORECAST CONCERN IS WITH A SYSTEM TO APPROACH THE GREAT LAKES
REGION WEDNESDAY NIGHT INTO THURSDAY...WITH GALE FORCE GUSTS TO 35
KT POSSIBLE ACROSS THE WHOLE LAKE DURING THIS PERIOD.
THE CENTER OF LARGE HIGH PRESSURE SPANNING SOUTHERN CANADA AND THE
UPPER MIDWEST WILL SHIFT SOUTHEAST THROUGH THE GREAT LAKES REGION
TO THE ATLANTIC COAST TODAY...WHILE A TROUGH OF LOW PRESSURE OVER
THE SOUTHERN PLAINS REMAINS SITUATED. AS THIS OCCURS...EXPECT EAST
WINDS TO DIMINISH TO 10 TO 15 KT WHILE TURNING TO THE SOUTHEAST
TODAY AND TONIGHT. DESPITE THIS TROUGH OF LOW PRESSURE DEEPENING
AS IT SLOWLY LIFTS NORTHEAST THROUGH THE CENTRAL PLAINS TONIGHT
INTO WEDNESDAY...A FAIRLY RELAXED GRADIENT OVER THE LAKE WILL HELP
LIGHT SOUTHEAST WINDS TO PERSIST DURING THE DAY WEDNESDAY.
ALTHOUGH THIS LOW WILL CONTINUE DEEPENING AS IT LIFTS TO THE UPPER
MIDWEST WEDNESDAY NIGHT AND AS THIS OCCURS...EXPECT THESE
SOUTHEAST WINDS TO BECOME SOUTH AND INCREASE TO 30KT. ONCE
AGAIN...ITS DURING THE WEDNESDAY NIGHT AND THURSDAY TIME FRAME
WHEN GALE FORCE GUSTS ARE POSSIBLE. WILL NEED TO MONITOR THIS TIME
FRAME AND IF INCREASING TRENDS OCCUR OVER THE NEXT FORECAST
RUNS...POSSIBLE GALES WILL NOT BE OUT OF THE QUESTION. THIS LOW
WILL MOVE EAST INTO SOUTHEAST ONTARIO AND QUEBEC THURSDAY NIGHT
INTO FRIDAY BEFORE EXITING TO THE NORTHEAST FRIDAY NIGHT. EXPECT
SOUTHWEST WINDS TO BECOME WEST STILL HOLDING AT 30 KT THROUGH
EARLY FRIDAY...BEFORE DIMINISHING LATER THAT DAY.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 3 PM
TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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Area Forecast Discussion
National Weather Service Lincoln IL
956 AM CDT Tue Oct 29 2013
.DISCUSSION...
ISSUED 955 AM CDT Tue Oct 29 2013
Large rain shield advancing eastward across Missouri, but the
eastern edge is being chewed up by the dry air that is currently
in place over Illinois. Initial radar returns will go toward
moistening up the column from the top down, so it will probably be
toward early afternoon before any steadier rains arrive in our
forecast area, and then it will be most likely south of I-72. Have
left slight chance PoP`s in across the northeast third of the CWA
for now, although latest guidance from the NAM/RAP/HRRR models is
indicating that any rain today will likely remain to the south,
and would probably hold off until mid or late afternoon if it does
manage to get that far north.
Have sent some updated zones/grids to freshen up the temperature
and rain trends, although no significant changes were made.
Geelhart
&&
.AVIATION...
ISSUED 600 AM CDT Tue Oct 29 2013
VFR conditions into the afternoon hours, then timing of the
MVFR/IFR cigs late this afternoon across the west and over the
remainder of the area tonight will be the main forecast challenge.
Band of showers over Missouri expected to weaken as it pushes east
into a drier air mass today. None the less, we do expect some
light shower activity to make it at least into the SPI and DEC in
the 15z-18z time frame. Forecast soundings continue to hold with
mainly VFR cigs despite the rain but feel with a persistent
moistening occurring at the mid and low levels of the atmosphere
over the next 12 to 18 hours...we should see deteriorating
conditions with respect to cigs and vsbys...and that would be
especially true for all areas tonight. Surface winds will be
southeast at 10 to 15 kts today and tonight.
Smith
&&
.PREV DISCUSSION...
ISSUED 254 AM CDT Tue Oct 29 2013
Main challenges with this forecast package are rain chances today
through Thursday and the potential for severe weather Thursday
afternoon.
Current upper air pattern features the main branch of the polar
jet flowing well to the north across central and eastern Canada.
Further southwest, a deep closed low has become cut-off from the
flow and is now meandering eastward across the Great Basin. This
low will be the dominant weather-maker across central Illinois for
the next several days as it slowly makes its way eastward.
SHORT TERM...Today through Thursday
Weak frontal boundary that dropped into the area yesterday
afternoon has now become stationary just north of the Ohio River.
To the north of the front, a dry E/NE flow prevails across central
Illinois early this morning, with 07z/2am dewpoints mainly in the
30s. This dry airmass will inhibit the eastward spread of precip
currently developing ahead of a weak short-wave trough over the
Plains. The onset of precip has been gradually delayed with each
model run over the past couple of days, with the 00z Oct 29 suite
now keeping the KILX CWA dry until afternoon. HRRR suggests light
showers may arrive in the Winchester/Jacksonville area around
midday, then will spread eastward to the Indiana border toward
evening. Will therefore go with a dry forecast this morning, then
will focus highest POPs across the southern CWA in closer proximity
to the stalled front this afternoon. Further north toward the I-74
corridor, little or no precip is expected today. Once this initial
wave passes, short-wave ridging in its wake will keep rain
chances low tonight. Despite lack of upper forcing, moistening
airmass and presence of surface boundary support low chance POPs
through the night.
As Great Basin upper low begins to approach from the west, surface
front will get nudged northward on Wednesday. Thanks to southerly
winds south of the boundary, afternoon high temperatures will rise
into the upper 60s and lower 70s. In addition, showers and
thunderstorms will become more widespread during the afternoon,
particularly along/west of the Illinois River.
Main rain/convective event is still slated for Wednesday night
into Thursday as strong cold front approaches from the west.
Models are generally in good agreement with their mass fields, but
still have some minor differences in QPF. As boundary nears,
copious amounts of moisture will advect northward from the Gulf of
Mexico, with precipitable water values nearing 1.50 on Thursday.
Given ample moisture, strong upper dynamics, and presence of
approaching cold front, will carry likely to categorical POPs
across the board Wednesday night and Thursday. Total rainfall with
this system will generally range from 1 to 1.50, with isolated
higher amounts within stronger storms.
Strong to potentially severe thunderstorms will be possible
Thursday afternoon as the front swings through the region:
however, details remain uncertain at this point. NAM/GFS forecast
soundings indicate a low CAPE/high shear environment in the warm
sector ahead of the front, with the greatest instability focused
further southeast from the Ohio River Valley to the western Gulf
Coast. Latest DAY 3 convective outlook from SPC highlights this
area for potential severe, but can not rule out a few strong
storms with damaging wind gusts further north across east-central
and southeast Illinois, particularly given impressive 0-6km bulk
shear values of 70 to 75kt.
LONG TERM...Friday through Monday
Cooler and drier weather will return by the end of the week, as
upper trough digs across the Great Lakes. GFS/ECMWF both suggest
clouds and a few showers will be possible across northeast
Illinois into north-central Indiana Friday into Saturday: however,
think these will remain northeast of central Illinois. High
pressure building into the Midwest will be the dominant weather
feature in the extended, resulting in cool highs in the 50s Friday
through Monday. Next chance for rain will likely hold off until
Tuesday when another system approaches from the west.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
653 AM CDT TUE OCT 29 2013
.DISCUSSION...
337 AM CDT
MAIN FORECAST CONCERNS CONTINUE TO BE WITH RAIN POTENTIAL AND MILDER
TEMPERATURES ASSOCIATED WITH A STRONG LOW PRESSURE SYSTEM WHICH WILL
MOVE THROUGH THE UPPER MIDWEST WEDNESDAY NIGHT THROUGH THURSDAY.
SHORT TERM...TODAY THROUGH THURSDAY...
UPPER FLOW PATTERN THIS MORNING IS DOMINATED BY A LARGE CLOSED LOW
OVER THE INTER-MOUNTAIN WEST...WITH SPLIT BUT MAINLY ZONAL FLOW
DOWNSTREAM ACROSS THE EASTERN CONUS. OVERNIGHT WATER VAPOR IMAGERY
DEPICTS A STRONG SHORT WAVE PROPAGATING ACROSS THE CENTRAL PLAINS
AND INTO THE MID-MISSOURI VALLEY...ALONG A LOW LEVEL BAROCLINIC ZONE
ASSOCIATED WITH A STATIONARY SURFACE FRONT WHICH STRETCHES WEST-EAST
FROM KANSAS TO THE OHIO VALLEY. FARTHER NORTH...AN ELONGATED AREA OF
SURFACE HIGH PRESSURE STRETCHED FROM NEAR LAKE WINNIPEG ACROSS THE
NORTHERN GREAT LAKES TO NEW ENGLAND.
THE PLAINS SHORT WAVE WILL CONTINUE TO TRACK EASTWARD ALONG THE
BAROCLINIC ZONE TODAY...WITH WARM ADVECTION/ISENTROPIC UPGLIDE
DEVELOPING ACROSS THE REGION. THE FOCUS FOR STRONGER FORCING AND LOW
LEVEL MOISTURE RETURN WILL REMAIN ACROSS FAR SOUTHERN IA/MISSOURI
AND DOWNSTATE ILLINOIS THROUGH THIS AFTERNOON HOWEVER...WITH MAINLY
JUST MID/HIGH CLOUDINESS EXPECTED ACROSS THE CWA AS LOW LEVEL FLOW
BACKS MORE SOUTHEAST. THIS WILL PULL IN DRIER AIR FROM UPSTREAM...
AS NOTED IN LAST EVENINGS 00Z SOUNDING FROM WILMINGTON OH. SOME
POTENTIAL PROBABLY EXISTS FOR A SPRINKLE OR TWO FROM OUR DEVELOPING
MID-DECK LATER TODAY...THOUGH IT APPEARS THAT ORGANIZED MEASURABLE
PRECIP CHANCES WILL REMAIN PRETTY LOW WITH THE SUITE OF GUIDANCE NOT
PRODUCING QPF. IT DOES APPEAR THAT PRECIP CHANCES WILL INCREASE
SLOWLY FROM THE SOUTH TONIGHT...AS THE ELEVATED BAROCLINIC ZONE
LIFTS SLOWLY NORTH IN RESPONSE TO PERSISTENT WARM ADVECTION ON
SOUTH-SOUTHWEST WINDS. OTHER THAN MOISTURE TRANSPORT/CONVERGENCE
ALONG THE ELEVATED WARM FRONT ON THE NOSE OF A 20-25 KT LOW LEVEL
JET TONIGHT...LITTLE IN THE WAY OF SHORT WAVE SUPPORT IS NOTED AND
HEIGHTS ACTUALLY RISE A BIT WITH WEAK RIDGING DEVELOPING ALOFT.
GUIDANCE DOES BRING SOME LIGHT QPF ACROSS THE SOUTHERN PORTIONS OF
THE CWA OVERNIGHT...THOUGH HAVE GENERALLY LOWERED POPS SIGNIFICANTLY
FROM PREVIOUS FORECAST BASED ON CURRENT GUIDANCE TRENDS.
THE WESTERN TROUGH BEGINS TO OPEN UP AND MOVE EAST WEDNESDAY AND
WEDNESDAY NIGHT...WITH RENEWED SURFACE LOW PRESSURE DEVELOPMENT
ACROSS THE CENTRAL PLAINS. THE LOW WILL LIFT ACROSS THE MID-MISSOURI
VALLEY BY WEDNESDAY EVENING AND INTO THE UPPER MISSISSIPPI VALLEY BY
THURSDAY MORNING...WITH SEVERAL MODELS DEPICTING A SHORT WAVE
APPROACHING THE CWA WEDNESDAY AFTERNOON/EVENING. A MUCH STRONGER
40-50 KT 850 MB JET IS INDICATED WEDNESDAY NIGHT WHICH IMPINGES ON
THE WARM FRONTAL ZONE AS IT LIFTS NORTH...SUGGESTING RAPIDLY
INCREASING POTENTIAL FOR RAIN AND A FEW THUNDERSTORMS BY LATE
WEDNESDAY AND CONTINUING INTO THURSDAY IN THE WARM SECTOR AHEAD OF
THE APPROACHING COLD FRONT. STRONG MOISTURE ADVECTION...PWATS
APPROACHING 1.5 INCHES...AND SURFACE DEW POINT TEMPS IN THE UPPER
50S...SUPPORT FAIRLY HIGH POPS DURING THIS PERIOD.
AS FOR TEMPERATURES...INCREASING CLOUD COVER AND EAST-SOUTHEAST LOW
LEVEL WINDS ARE EXPECTED TO KEEP RISES IN CHECK DESPITE WARMING
ALOFT TODAY. WARMER TEMPS...IN THE 60S...WILL SPREAD NORTH WITH THE
WARM FRONT INTO THE SOUTHERN CWA WEDNESDAY AND ACROSS THE ENTIRE
AREA THURSDAY. RISING TEMPS ARE LIKELY WEDNESDAY NIGHT.
LONG TERM...FRIDAY-MONDAY...
THE LARGE SCALE UPPER TROUGH WILL LINGER ACROSS THE REGION FRIDAY
AND SATURDAY AS ADDITIONAL SHORT WAVE ENERGY DIGS IN FROM THE
NORTHWEST. COOL ADVECTION AND CYCLONIC LOW LEVEL FLOW IN SURFACE
TROUGHING OVER THE LAKES WILL LIKELY SUPPORT CONSIDERABLE CLOUD
COVER INITIALLY...WITH THE POTENTIAL FOR SOME SPRINKLES/SHOWERS
ESPECIALLY FRIDAY NIGHT AND SATURDAY WITH A SECONDARY PUSH OF COLDER
AIR. SURFACE HIGH PRESSURE THEN EVENTUALLY SPREADS ACROSS THE REGION
LATE SATURDAY NIGHT AND SUNDAY. LONG RANGE MODEL SOLUTIONS MOVE THE
HIGH QUICKLY OFF TO THE EAST SUNDAY NIGHT...WITH ANOTHER LOW PASSING
NORTHWEST OF THE FORECAST AREA MONDAY. THIS SETS UP ANOTHER PERIOD
OF SOUTH FLOW AND A RETURN OF RAIN CHANCES ESPECIALLY WEST ON
MONDAY. TEMPS COOL TO THE UPPER 40S/LOW 50S OVER THE WEEKEND BEFORE
MODERATING MONDAY.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* LINGERING MVFR CEILINGS THRU 15Z TODAY FOR ORD ONLY.
* EAST WINDS BECOMING SOUTHEAST W/ MID TEEN GUSTS BY MID/LATE
MORNING.
* MVFR CONDITIONS RETURN EARLY WEDNESDAY MORNING.
* -SHRA MOVING NEAR THE TERMINALS TONIGHT.
RODRIGUEZ
//DISCUSSION...UPDATED 12Z...
MVFR STRATUS PERSISTING PRIMARILY OVER ORD EARLY THIS
MORNING...WITH ORD BEING IN A FAVORABLE AXIS FOR PERSISTENT
DEVELOPMENT. THESE CONDITIONS WILL REMAIN OVER THE NEXT 2-3 HOURS
BEFORE THESE CEILINGS LIFT NORTH OF THE TERMINALS. SHOULD ONLY
AFFECT ORD...BUT COULD COME CLOSE TO DPA AS THIS LIFTS NORTHWARD.
CEILINGS ARE CURRENTLY HOLDING AT 1500FT...WITH THEM NOT
ANTICIPATED TO LOWER ANY FURTHER. WITH THE DEPARTURE OF THIS LOW
STRATUS...ONLY MID/HIGH LEVEL CLOUD COVER EXPECTED TODAY INTO
TONIGHT AS MOISTURE STREAMS OUT AHEAD OF AN APPROACHING SYSTEM TO
THE WEST. SEVERAL MID LEVEL DISTURBANCES WILL MOVE ACROSS THE
REGION THIS EVENING WITH THE LEADING EDGE OF THE CURRENT PRECIP
SHIELD OVER THE CENTRAL PLAINS WORKING ITS WAY TOWARDS THE
TERMINALS TONIGHT. ALTHOUGH OUTSIDE OF SOME SCT LIGHT SHOWERS NEAR
RFD...IT DOES APPEAR AS IF BETTER FORCING WILL REMAIN TO THE SOUTH
OF THE TERMINALS AND LIKEWISE PRECIP AXIS. ALTHOUGH FURTHER
SATURATION IS EXPECTED OVERNIGHT INTO EARLY WEDNESDAY MORNING WITH
CEILINGS LOWERING...AND MVFR CONDITIONS ONCE AGAIN RETURNING OVER
THE TERMINALS.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* HIGH CONFIDENCE WITH CEILINGS/TRENDS THIS MORNING AND
TODAY...MEDIUM CONFIDENCE EARLY WEDNESDAY MORNING.
* HIGH CONFIDENCE WITH WIND SPEED/DIRECTION.
* LOW MEDIUM CONFIDENCE WITH -SHRA/TRENDS TONIGHT.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...SHRA W/ CHANCE OF TSRA.
THURSDAY...SHRA W/ CHANCE OF TSRA.
FRIDAY...CHANCE OF SHRA EARLY...OTHERWISE VFR.
SATURDAY...CHANCE OF SHRA...OTHERWISE VFR.
SUNDAY...VFR.
MONDAY...SLIGHT CHANCE OF SHRA...OTHERWISE VFR.
RODRIGUEZ
&&
.MARINE...
418 AM CDT
MAIN FORECAST CONCERN IS WITH A SYSTEM TO APPROACH THE GREAT LAKES
REGION WEDNESDAY NIGHT INTO THURSDAY...WITH GALE FORCE GUSTS TO 35
KT POSSIBLE ACROSS THE WHOLE LAKE DURING THIS PERIOD.
THE CENTER OF LARGE HIGH PRESSURE SPANNING SOUTHERN CANADA AND THE
UPPER MIDWEST WILL SHIFT SOUTHEAST THROUGH THE GREAT LAKES REGION
TO THE ATLANTIC COAST TODAY...WHILE A TROUGH OF LOW PRESSURE OVER
THE SOUTHERN PLAINS REMAINS SITUATED. AS THIS OCCURS...EXPECT EAST
WINDS TO DIMINISH TO 10 TO 15 KT WHILE TURNING TO THE SOUTHEAST
TODAY AND TONIGHT. DESPITE THIS TROUGH OF LOW PRESSURE DEEPENING
AS IT SLOWLY LIFTS NORTHEAST THROUGH THE CENTRAL PLAINS TONIGHT
INTO WEDNESDAY...A FAIRLY RELAXED GRADIENT OVER THE LAKE WILL HELP
LIGHT SOUTHEAST WINDS TO PERSIST DURING THE DAY WEDNESDAY.
ALTHOUGH THIS LOW WILL CONTINUE DEEPENING AS IT LIFTS TO THE UPPER
MIDWEST WEDNESDAY NIGHT AND AS THIS OCCURS...EXPECT THESE
SOUTHEAST WINDS TO BECOME SOUTH AND INCREASE TO 30KT. ONCE
AGAIN...ITS DURING THE WEDNESDAY NIGHT AND THURSDAY TIME FRAME
WHEN GALE FORCE GUSTS ARE POSSIBLE. WILL NEED TO MONITOR THIS TIME
FRAME AND IF INCREASING TRENDS OCCUR OVER THE NEXT FORECAST
RUNS...POSSIBLE GALES WILL NOT BE OUT OF THE QUESTION. THIS LOW
WILL MOVE EAST INTO SOUTHEAST ONTARIO AND QUEBEC THURSDAY NIGHT
INTO FRIDAY BEFORE EXITING TO THE NORTHEAST FRIDAY NIGHT. EXPECT
SOUTHWEST WINDS TO BECOME WEST STILL HOLDING AT 30 KT THROUGH
EARLY FRIDAY...BEFORE DIMINISHING LATER THAT DAY.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 3 PM
TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
605 AM CDT Tue Oct 29 2013
.DISCUSSION...
ISSUED 254 AM CDT Tue Oct 29 2013
Main challenges with this forecast package are rain chances today
through Thursday and the potential for severe weather Thursday
afternoon.
Current upper air pattern features the main branch of the polar
jet flowing well to the north across central and eastern Canada.
Further southwest, a deep closed low has become cut-off from the
flow and is now meandering eastward across the Great Basin. This
low will be the dominant weather-maker across central Illinois for
the next several days as it slowly makes its way eastward.
SHORT TERM...Today through Thursday
Weak frontal boundary that dropped into the area yesterday
afternoon has now become stationary just north of the Ohio River.
To the north of the front, a dry E/NE flow prevails across central
Illinois early this morning, with 07z/2am dewpoints mainly in the
30s. This dry airmass will inhibit the eastward spread of precip
currently developing ahead of a weak short-wave trough over the
Plains. The onset of precip has been gradually delayed with each
model run over the past couple of days, with the 00z Oct 29 suite
now keeping the KILX CWA dry until afternoon. HRRR suggests light
showers may arrive in the Winchester/Jacksonville area around
midday, then will spread eastward to the Indiana border toward
evening. Will therefore go with a dry forecast this morning, then
will focus highest POPs across the southern CWA in closer proximity
to the stalled front this afternoon. Further north toward the I-74
corridor, little or no precip is expected today. Once this initial
wave passes, short-wave ridging in its wake will keep rain
chances low tonight. Despite lack of upper forcing, moistening
airmass and presence of surface boundary support low chance POPs
through the night.
As Great Basin upper low begins to approach from the west, surface
front will get nudged northward on Wednesday. Thanks to southerly
winds south of the boundary, afternoon high temperatures will rise
into the upper 60s and lower 70s. In addition, showers and
thunderstorms will become more widespread during the afternoon,
particularly along/west of the Illinois River.
Main rain/convective event is still slated for Wednesday night
into Thursday as strong cold front approaches from the west.
Models are generally in good agreement with their mass fields, but
still have some minor differences in QPF. As boundary nears,
copious amounts of moisture will advect northward from the Gulf of
Mexico, with precipitable water values nearing 1.50 on Thursday.
Given ample moisture, strong upper dynamics, and presence of
approaching cold front, will carry likely to categorical POPs
across the board Wednesday night and Thursday. Total rainfall with
this system will generally range from 1 to 1.50, with isolated
higher amounts within stronger storms.
Strong to potentially severe thunderstorms will be possible
Thursday afternoon as the front swings through the region:
however, details remain uncertain at this point. NAM/GFS forecast
soundings indicate a low CAPE/high shear environment in the warm
sector ahead of the front, with the greatest instability focused
further southeast from the Ohio River Valley to the western Gulf
Coast. Latest DAY 3 convective outlook from SPC highlights this
area for potential severe, but can not rule out a few strong
storms with damaging wind gusts further north across east-central
and southeast Illinois, particularly given impressive 0-6km bulk
shear values of 70 to 75kt.
LONG TERM...Friday through Monday
Cooler and drier weather will return by the end of the week, as
upper trough digs across the Great Lakes. GFS/ECMWF both suggest
clouds and a few showers will be possible across northeast
Illinois into north-central Indiana Friday into Saturday: however,
think these will remain northeast of central Illinois. High
pressure building into the Midwest will be the dominant weather
feature in the extended, resulting in cool highs in the 50s Friday
through Monday. Next chance for rain will likely hold off until
Tuesday when another system approaches from the west.
&&
.AVIATION...
ISSUED 600 AM CDT Tue Oct 29 2013
VFR conditions into the afternoon hours, then timing of the
MVFR/IFR cigs late this afternoon across the west and over the
remainder of the area tonight will be the main forecast challenge.
Band of showers over Missouri expected to weaken as it pushes east
into a drier air mass today. None the less, we do expect some
light shower activity to make it at least into the SPI and DEC in
the 15z-18z time frame. Forecast soundings continue to hold with
mainly VFR cigs despite the rain but feel with a persistent
moistening occurring at the mid and low levels of the atmosphere
over the next 12 to 18 hours...we should see deteriorating
conditions with respect to cigs and vsbys...and that would be
especially true for all areas tonight. Surface winds will be
southeast at 10 to 15 kts today and tonight.
Smith
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
338 AM CDT TUE OCT 29 2013
.DISCUSSION...
337 AM CDT
MAIN FORECAST CONCERNS CONTINUE TO BE WITH RAIN POTENTIAL AND MILDER
TEMPERATURES ASSOCIATED WITH A STRONG LOW PRESSURE SYSTEM WHICH WILL
MOVE THROUGH THE UPPER MIDWEST WEDNESDAY NIGHT THROUGH THURSDAY.
SHORT TERM...TODAY THROUGH THURSDAY...
UPPER FLOW PATTERN THIS MORNING IS DOMINATED BY A LARGE CLOSED LOW
OVER THE INTER-MOUNTAIN WEST...WITH SPLIT BUT MAINLY ZONAL FLOW
DOWNSTREAM ACROSS THE EASTERN CONUS. OVERNIGHT WATER VAPOR IMAGERY
DEPICTS A STRONG SHORT WAVE PROPAGATING ACROSS THE CENTRAL PLAINS
AND INTO THE MID-MISSOURI VALLEY...ALONG A LOW LEVEL BAROCLINIC ZONE
ASSOCIATED WITH A STATIONARY SURFACE FRONT WHICH STRETCHES WEST-EAST
FROM KANSAS TO THE OHIO VALLEY. FARTHER NORTH...AN ELONGATED AREA OF
SURFACE HIGH PRESSURE STRETCHED FROM NEAR LAKE WINNIPEG ACROSS THE
NORTHERN GREAT LAKES TO NEW ENGLAND.
THE PLAINS SHORT WAVE WILL CONTINUE TO TRACK EASTWARD ALONG THE
BAROCLINIC ZONE TODAY...WITH WARM ADVECTION/ISENTROPIC UPGLIDE
DEVELOPING ACROSS THE REGION. THE FOCUS FOR STRONGER FORCING AND LOW
LEVEL MOISTURE RETURN WILL REMAIN ACROSS FAR SOUTHERN IA/MISSOURI
AND DOWNSTATE ILLINOIS THROUGH THIS AFTERNOON HOWEVER...WITH MAINLY
JUST MID/HIGH CLOUDINESS EXPECTED ACROSS THE CWA AS LOW LEVEL FLOW
BACKS MORE SOUTHEAST. THIS WILL PULL IN DRIER AIR FROM UPSTREAM...
AS NOTED IN LAST EVENINGS 00Z SOUNDING FROM WILMINGTON OH. SOME
POTENTIAL PROBABLY EXISTS FOR A SPRINKLE OR TWO FROM OUR DEVELOPING
MID-DECK LATER TODAY...THOUGH IT APPEARS THAT ORGANIZED MEASURABLE
PRECIP CHANCES WILL REMAIN PRETTY LOW WITH THE SUITE OF GUIDANCE NOT
PRODUCING QPF. IT DOES APPEAR THAT PRECIP CHANCES WILL INCREASE
SLOWLY FROM THE SOUTH TONIGHT...AS THE ELEVATED BAROCLINIC ZONE
LIFTS SLOWLY NORTH IN RESPONSE TO PERSISTENT WARM ADVECTION ON
SOUTH-SOUTHWEST WINDS. OTHER THAN MOISTURE TRANSPORT/CONVERGENCE
ALONG THE ELEVATED WARM FRONT ON THE NOSE OF A 20-25 KT LOW LEVEL
JET TONIGHT...LITTLE IN THE WAY OF SHORT WAVE SUPPORT IS NOTED AND
HEIGHTS ACTUALLY RISE A BIT WITH WEAK RIDGING DEVELOPING ALOFT.
GUIDANCE DOES BRING SOME LIGHT QPF ACROSS THE SOUTHERN PORTIONS OF
THE CWA OVERNIGHT...THOUGH HAVE GENERALLY LOWERED POPS SIGNIFICANTLY
FROM PREVIOUS FORECAST BASED ON CURRENT GUIDANCE TRENDS.
THE WESTERN TROUGH BEGINS TO OPEN UP AND MOVE EAST WEDNESDAY AND
WEDNESDAY NIGHT...WITH RENEWED SURFACE LOW PRESSURE DEVELOPMENT
ACROSS THE CENTRAL PLAINS. THE LOW WILL LIFT ACROSS THE MID-MISSOURI
VALLEY BY WEDNESDAY EVENING AND INTO THE UPPER MISSISSIPPI VALLEY BY
THURSDAY MORNING...WITH SEVERAL MODELS DEPICTING A SHORT WAVE
APPROACHING THE CWA WEDNESDAY AFTERNOON/EVENING. A MUCH STRONGER
40-50 KT 850 MB JET IS INDICATED WEDNESDAY NIGHT WHICH IMPINGES ON
THE WARM FRONTAL ZONE AS IT LIFTS NORTH...SUGGESTING RAPIDLY
INCREASING POTENTIAL FOR RAIN AND A FEW THUNDERSTORMS BY LATE
WEDNESDAY AND CONTINUING INTO THURSDAY IN THE WARM SECTOR AHEAD OF
THE APPROACHING COLD FRONT. STRONG MOISTURE ADVECTION...PWATS
APPROACHING 1.5 INCHES...AND SURFACE DEW POINT TEMPS IN THE UPPER
50S...SUPPORT FAIRLY HIGH POPS DURING THIS PERIOD.
AS FOR TEMPERATURES...INCREASING CLOUD COVER AND EAST-SOUTHEAST LOW
LEVEL WINDS ARE EXPECTED TO KEEP RISES IN CHECK DESPITE WARMING
ALOFT TODAY. WARMER TEMPS...IN THE 60S...WILL SPREAD NORTH WITH THE
WARM FRONT INTO THE SOUTHERN CWA WEDNESDAY AND ACROSS THE ENTIRE
AREA THURSDAY. RISING TEMPS ARE LIKELY WEDNESDAY NIGHT.
LONG TERM...FRIDAY-MONDAY...
THE LARGE SCALE UPPER TROUGH WILL LINGER ACROSS THE REGION FRIDAY
AND SATURDAY AS ADDITIONAL SHORT WAVE ENERGY DIGS IN FROM THE
NORTHWEST. COOL ADVECTION AND CYCLONIC LOW LEVEL FLOW IN SURFACE
TROUGHING OVER THE LAKES WILL LIKELY SUPPORT CONSIDERABLE CLOUD
COVER INITIALLY...WITH THE POTENTIAL FOR SOME SPRINKLES/SHOWERS
ESPECIALLY FRIDAY NIGHT AND SATURDAY WITH A SECONDARY PUSH OF COLDER
AIR. SURFACE HIGH PRESSURE THEN EVENTUALLY SPREADS ACROSS THE REGION
LATE SATURDAY NIGHT AND SUNDAY. LONG RANGE MODEL SOLUTIONS MOVE THE
HIGH QUICKLY OFF TO THE EAST SUNDAY NIGHT...WITH ANOTHER LOW PASSING
NORTHWEST OF THE FORECAST AREA MONDAY. THIS SETS UP ANOTHER PERIOD
OF SOUTH FLOW AND A RETURN OF RAIN CHANCES ESPECIALLY WEST ON
MONDAY. TEMPS COOL TO THE UPPER 40S/LOW 50S OVER THE WEEKEND BEFORE
MODERATING MONDAY.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* POSSIBLE MVFR CEILINGS EARLY THIS NEXT HOUR FOR BOTH ORD/MDW.
* NORTHEAST WINDS BECOMING MORE EASTERLY LATER THIS MORNING...AND
THEN EVENTUALLY SOUTHEAST BY MID/LATE MORNING.
RODRIGUEZ
//DISCUSSION...UPDATED 06Z...
LATEST OBS AND SATELLITE IMAGERY DEPICTING LOW LEVEL STRATUS
LINGERING ACROSS PORTIONS OF NORTHEAST ILLINOIS EARLY THIS
MORNING. ALTHOUGH...FLOW WILL BECOME MORE EAST AND THEN SOUTHEAST
THROUGH THIS MORNING WITH MOST OF THIS CLOUD COVER TO MOVE NORTH
OF THE TERMINALS. THIS TREND SHOULD OCCUR HERE IN THE NEAR TERM
BUT AS THIS OCCURS...THESE MVFR CEILINGS COULD STILL MOVE ACROSS
ORD/MDW. SO HAVE INCLUDED A TEMPO GROUP FOR THIS FIRST HOUR TO
SHOW THIS POSSIBILITY. WITH THESE LOW CEILINGS TO THE
NORTH...ONLY MID/HIGH LEVEL CLOUD COVER EXPECTED THROUGH THE
FORECAST PERIOD AND WITH ANY PRECIP APPROACHING LATER THIS EVENING
TO STAY SOUTHWEST OF ALL THE TERMINALS. WINDS WILL CONTINUE A
STEADY TREND FROM THE NORTHEAST TO THE EAST AND SOUTHEAST THIS
MORNING...MAINTAINING THIS DIRECTION THROUGH MOST OF THE DAY
BEFORE TURNING MORE SOUTH SOUTHEAST LATER THIS EVENING.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE WITH CEILING TRENDS.
* HIGH CONFIDENCE WITH WIND SPEED/DIRECTION.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z SUNDAY...UPDATED 00Z...
WEDNESDAY...CHC OF RAIN. SLIGHT CHC OF THUNDER LATE WED NGT. MVFR
LIKELY WITH OCCASIONAL IFR CIGS.
THURSDAY...RAIN LIKELY W/SLIGHT CHC OF THUNDER. MVFR CIGS.
FRIDAY...SLIGHT CHANCE OF RAIN. MVFR POSSIBLE.
SATURDAY THROUGH SUNDAY...VFR.
BEACHLER
&&
.MARINE...
226 PM CDT
BREEZY CONDITIONS EXPECTED THROUGH MUCH OF THE WEEK...WITH PERIOD
OF GALES POSSIBLE WEDNESDAY NIGHT INTO THURSDAY. TODAY...A COLD
FRONT HAS CLEARED THE SOUTH END OF LAKE MICHIGAN WITH STRONG HIGH
PRESSURE BUILDING EAST ACROSS THE CANADIAN PRAIRIES. THE HIGH WILL
SHIFT ESE ACROSS THE EASTERN GREAT LAKES BY LATE TUESDAY...BUT THE
GRADIENT WILL REMAIN MODERATELY TIGHT ACROSS SOUTHERN LAKE
MICHIGAN WHERE WINDS WILL VEER FROM THE NORTHEAST TODAY TO
SOUTHEAST TUESDAY NIGHT...BUT GENERALLY STAY IN THE 15 TO 20 KT
RANGE. WINDS WILL BE WEAKER ACROSS THE NORTH HALF OF THE LAKE
CLOSER TO THE RIDGE AXIS. MIDWEEK...DEEP LOW PRESSURE IS EXPECTED
TO DEVELOP FROM THE PLAINS INTO THE MIDWEST. THIS LOW WILL STILL
BE DEEPENING AS IT MOVES ACROSS THE UPPER PENINSULA OF MICHIGAN
THURSDAY LEADING TO STRONG SOUTHERLY WINDS AHEAD OF THE LOW. IT
APPEARS THAT THE GALES MAY OCCUR WEDNESDAY NIGHT INTO THURSDAY. A
COLD FRONT WILL SWEEP ACROSS THE LAKE ON THURSDAY EVENING WITH
WINDS TURNING WEST TO NORTHWEST AND REMAINING ELEVATED AROUND 30
KTS THROUGH SATURDAY.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 3 PM
TUESDAY.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
254 AM CDT Tue Oct 29 2013
.DISCUSSION...
ISSUED 254 AM CDT Tue Oct 29 2013
Main challenges with this forecast package are rain chances today
through Thursday and the potential for severe weather Thursday
afternoon.
Current upper air pattern features the main branch of the polar
jet flowing well to the north across central and eastern Canada.
Further southwest, a deep closed low has become cut-off from the
flow and is now meandering eastward across the Great Basin. This
low will be the dominant weather-maker across central Illinois for
the next several days as it slowly makes its way eastward.
SHORT TERM...Today through Thursday
Weak frontal boundary that dropped into the area yesterday
afternoon has now become stationary just north of the Ohio River.
To the north of the front, a dry E/NE flow prevails across central
Illinois early this morning, with 07z/2am dewpoints mainly in the
30s. This dry airmass will inhibit the eastward spread of precip
currently developing ahead of a weak short-wave trough over the
Plains. The onset of precip has been gradually delayed with each
model run over the past couple of days, with the 00z Oct 29 suite
now keeping the KILX CWA dry until afternoon. HRRR suggests light
showers may arrive in the Winchester/Jacksonville area around
midday, then will spread eastward to the Indiana border toward
evening. Will therefore go with a dry forecast this morning, then
will focus highest POPs across the southern CWA in closer proximity
to the stalled front this afternoon. Further north toward the I-74
corridor, little or no precip is expected today. Once this initial
wave passes, short-wave ridging in its wake will keep rain
chances low tonight. Despite lack of upper forcing, moistening
airmass and presence of surface boundary support low chance POPs
through the night.
As Great Basin upper low begins to approach from the west, surface
front will get nudged northward on Wednesday. Thanks to southerly
winds south of the boundary, afternoon high temperatures will rise
into the upper 60s and lower 70s. In addition, showers and
thunderstorms will become more widespread during the afternoon,
particularly along/west of the Illinois River.
Main rain/convective event is still slated for Wednesday night
into Thursday as strong cold front approaches from the west.
Models are generally in good agreement with their mass fields, but
still have some minor differences in QPF. As boundary nears,
copious amounts of moisture will advect northward from the Gulf of
Mexico, with precipitable water values nearing 1.50 on Thursday.
Given ample moisture, strong upper dynamics, and presence of
approaching cold front, will carry likely to categorical POPs
across the board Wednesday night and Thursday. Total rainfall with
this system will generally range from 1 to 1.50, with isolated
higher amounts within stronger storms.
Strong to potentially severe thunderstorms will be possible
Thursday afternoon as the front swings through the region:
however, details remain uncertain at this point. NAM/GFS forecast
soundings indicate a low CAPE/high shear environment in the warm
sector ahead of the front, with the greatest instability focused
further southeast from the Ohio River Valley to the western Gulf
Coast. Latest DAY 3 convective outlook from SPC highlights this
area for potential severe, but can not rule out a few strong
storms with damaging wind gusts further north across east-central
and southeast Illinois, particularly given impressive 0-6km bulk
shear values of 70 to 75kt.
LONG TERM...Friday through Monday
Cooler and drier weather will return by the end of the week, as
upper trough digs across the Great Lakes. GFS/ECMWF both suggest
clouds and a few showers will be possible across northeast
Illinois into north-central Indiana Friday into Saturday: however,
think these will remain northeast of central Illinois. High
pressure building into the Midwest will be the dominant weather
feature in the extended, resulting in cool highs in the 50s Friday
through Monday. Next chance for rain will likely hold off until
Tuesday when another system approaches from the west.
Barnes
&&
.AVIATION...
ISSUED 1151 PM CDT Mon Oct 28 2013
VFR conditions will prevail at all TAF sites next 24hrs. High
cirrus will continue overnight and into the morning hours. Then
mid clouds will overspread the TAF sites during the late morning.
As the first wave approaches from the west and tries to make its
way over the mid level ridge, pcpn will diminish as it moves
toward the area. So, initial pcpn will go to saturate the lower
levels first, in the afternoon. So will begin to see some lower
clouds around 5kft in the afternoon with little bit lower mid
clouds. Then by evening, after 00Z, lower clouds will thicken up
and middle clouds will get lower too. At this point, unsure how
widespread pcpn will be. Thinking it could be very light or
scattered, so will have just VCSH for now. Winds will be
northeasterly overnight and then become southeasterly tomorrow
afternoon and continue into the evening hours. Wind speeds will
generally be below 10kts.
Auten
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
645 PM CDT WED OCT 30 2013
.SHORT TERM /TONIGHT/...
ISSUED AT 314 PM CDT WED OCT 30 2013
INTERESTING FORECAST TONIGHT WITH THE SURFACE LOW OVER NW MO AND A
TROUGH EXTENDING INTO CENTRAL IOWA LOCATED FROM ALGONA THROUGH
CRESTON. THE WARM FRONT ASSOCIATED WITH THIS LOW IS STILL IN
NORTHERN MO AND IS JUST STARTING TO INCH INTO FAR SOUTHERN/SW IA.
THE MODELS HAVE CAUGHT ON TO TRENDING DOWN WITH POPS/QPF...
ESPECIALLY ACROSS THE WEST. THE RAP ACTUALLY HAD THE BEST HANDLE ON
THINGS FOR TONIGHT. ALTHOUGH ALL MODELS WERE TRENDING LOWER WITH
POPS...NAM/GFS STILL LOOKED A BIT OVERDONE AND HIT QPF MORE THAN
WHAT I THINK WILL OCCUR. CONSEQUENTLY THE AREA FOR PRECIP THIS
EVENING WILL BE ALONG OUR FAR SOUTHERN AND EASTERN AREAS...NEAR THE
FRONTAL BOUNDARY WHERE SHOWERS AND ISOLATED TO SCATTERED STORMS ARE
STILL POSSIBLE. THE THUNDERSTORMS WILL STILL BE CAPABLE OF
PRODUCING MODERATE TO HEAVY RAINFALL THOUGH I THINK THE HEAVIEST
RAIN WILL OCCUR SE OF OUR FORECAST AREA.
I END POPS THIS EVENING FROM W/NW TO ABOUT THE I-35 CORRIDOR BY 12Z.
INSTABILITY AND FORCING SHIFTS EAST OVERNIGHT AS WELL SO THUNDER
CHANCES DIMINISH AFTER 06Z BUT STILL LINGER ACROSS THE FAR SOUTHEAST
BY 12Z. PATCHY FOG STILL A CONCERN AS SOUNDING SHOW SATURATED
SOUNDINGS ACROSS CENTRAL IOWA. FOR NOW I AM NOT CONSIDERING DENSE
FOG THOUGH LOWER LYING AREAS AND LOCATIONS THAT RECEIVED AN INCH OF
RAIN TODAY COULD SEE AT LEAST LOCALIZED DENSE FOG OVERNIGHT. I WILL
BRIEF THE EVENING SHIFT ON THE POSSIBILITY OF DENSE FOG LATER
TONIGHT.
.LONG TERM /THURSDAY THROUGH WEDNESDAY/...
ISSUED AT 314 PM CDT WED OCT 30 2013
MAIN CHALLENGE IN THE NEAR TERM WILL BE THE EXITING OF OVERNIGHT
PRECIPITATION INTO THURSDAY MORNING. THE BULK OF THE RAIN AND ANY
LEFTOVER ISO THUNDER WILL BE EXITING THE AREA BY EARLY AFTERNOON
WITH SOME LINGERING SHOWERS SOUTHEAST THROUGH 00Z. OTHERWISE
...EXPECTING SIGNIFICANT CLOUD COVER OVER MUCH OF THE SOUTHEAST
HALF THROUGH MIDDAY FOLLOWED BY PARTIAL CLEARING DURING THE
AFTERNOON. SUBSIDENCE SHOULD BE OFFSET BY SOME COLD AIR ADVECTION
WHICH WILL RESULT IN LINGERING CLOUDS FOR THE DAY. HIGHS WILL ONCE
AGAIN REACH THE UPPER 50S SOUTHEAST WITH NEAR 50 HIGHS FAR NORTH
WHERE COLD AIR WILL ARRIVE SOONER. A SECONDARY COLD FRONT/WEAK WAVE
WILL TRACK SOUTHEAST THURSDAY EVENING. THIS WILL CONTINUE CLOUD
COVER ACROSS THE AREA SO OVERNIGHT LOWS WILL BE HELD IN CHECK
COMPARED TO CLEARING. LIMITED WARM AIR ADVECTION IS EXPECTED ON
FRIDAY WITH CLOUDS...SO HIGHS WILL ONCE AGAIN STRUGGLE TO REACH THE
LOWER TO MID 50S FOR THE DAY. THE MODELS ARE CONTINUING TO PICK UP A
WAVE IN THE FLOW OVER THE NORTH PACIFIC/GULF OF ALASKA NOW...WHICH
WILL RACE EAST AND THEN DROP SOUTHEAST INTO THE AREA BY FRIDAY
AFTERNOON. THOUGH GENERALLY MOISTURE STARVED...THIS FEATURE SHOULD
AMPLIFY AS IT HOOKS UP WITH THE H500 TROUGH STILL LINGERING OVER THE
CENTRAL PLAINS. THE TIMING OF THE FEATURE SUGGESTS THAT SOME LIGHT
SHOWERS MAY OCCUR LATE FRIDAY AFTERNOON OR EARLY EVENING PRIOR TO
THE SYSTEM MOVING EAST. THE EURO/GEM ALSO SUGGEST A BRIEF SHOT OF
COLD AIR ADVECTION FRIDAY NIGHT WITH THIS FEATURE REINFORCING THE
COOL WEATHER INTO SATURDAY. BOTH THE GFS AND NAM ARE FASTER WITH
ARRIVAL/DEPARTURE AND ARE ALREADY WARMING UP THE COLUMN SATURDAY
AFTERNOON. FOR NOW...WILL LEAN TOWARD MED RANGE SOLUTIONS AND DELAY
ONSET OF WARM AIR UNTIL LATER SATURDAY AND SUNDAY. WITH A H500
TROUGH JUST OFF THE COAST OF BRITISH COLUMBIA EXPECTED TO DIG
ONSHORE AND DEEPEN OVER THE NORTHERN ROCKIES BY SUNDAY...A NICE
FETCH OF SOUTHERLY FLOW WILL DEVELOP ACROSS THE REGION FOR SUNDAY.
H850 TEMPS WILL QUICKLY TURN THE CORNER AND RISE TO 3C TO 6C BY LATE
DAY...COMBINED WITH MIXING TO 875MB MAXT SHOULD RISE TO THE MID TO
UPPER 50S SOUTH AND AND LOWER 50S SOUTH. ALONG WITH THE INCREASING
SOUTHERLY FLOW...MOISTURE WILL BE RETURNING BY LATE SUNDAY NIGHT
THROUGH TUESDAY AS A DEEP SUBTROPICAL CONNECTION SETS UP WITH THE
GULF/PACIFIC BEING CHANNELED NORTH INTO THE CENTRAL PLAINS AND OHIO
RIVER VALLEY. SOME QUESTION ABOUT THE EXACT POSITION...BUT OVERALL
ADDITIONAL RAINFALL...EVEN IF MODEST OVER THE AREA...WILL BE
WELCOMED TO ADD TO TODAYS RAIN EVENT. IT APPEARS THAT THERE WILL
BE SEVERAL WAVES APPROACHING THE AREA BY EARLY NEXT WEEK INTO
MIDWEEK KEEPING RAINFALL IN THE FORECAST THROUGH AT LEAST
WEDNESDAY. FOR NOW...MODESTLY COOLER AIR FOLLOWS THE SYSTEM SO
HIGHS SHOULD TRACK JUST SLIGHTLY BELOW NORMAL FOR THIS TIME OF THE
YEAR.
&&
.AVIATION...31/00Z
ISSUED AT 638 PM CDT WED OCT 30 2013
PERSISTENT STRATUS WILL CONTINUE TO AFFECT SITES THROUGH
12Z...WITH MVFR AND LOWER CEILINGS. RA/TSRA WILL AFFECT KOTM
THROUGH 06Z BEFORE SYSTEM PUSHES EAST. LOW IFR AND LIFR CEILINGS
AND VISIBILITIES WILL BE POSSIBLE AT SITES...ESPECIALLY IN THE
EAST...KOTM/KALO AND WITH AMPLE LOW LEVEL MOISTURE MAY SEE BR/FG
NEAR 12Z. SYSTEM WILL PULL EAST...WITH CONDITIONS RETURNING TO VFR
BY END OF PERIOD.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...FAB
LONG TERM...REV
AVIATION...AWB
AREA FORECAST DISCUSSION
NWS TOPEKA KS
625 AM CDT Tue Oct 29 2013
...AVIATION UPDATE...
.SHORT TERM...(Today and Tonight)
Issued at 359 AM CDT TUE OCT 29 2013
08Z water vapor imagery shows a closed low over the Great Basin. At
the surface, low pressure was centered over the TX panhandle where a
cold front was pushing south southeast. An inverted trough stretched
northeast from the area of low pressure across central KS, just west
of the forecast area. Southerly flow continues to feed a relatively
moist airmass into the MCS that has developed over eastern KS.
For today and tonight, the thinking is that once the MCS passes to
the east of the forecast area mid to late morning, that there should
be a general lull in widespread precip. Much of the forcing for the
MCS has been derived from the low level jet and isentropic assent
feeding moisture north. Models show the low level jet veering to the
southwest by mid morning which should focus the better forcing to
the east across MO. Will keep a POP through the day however as low
level isentropic surfaces maintain some weak lift within a saturated
stable layer shown by the model forecast soundings. Because of this
there could be some patchy drizzle throughout the day, although
there are signs this lift weakens through the afternoon. The GFS and
NA< also maintain some modest instability within the warm sector
mainly south of the area. The biggest question for today is how far
a weak low will propagate northeast along the inverted trough into
north central KS. This has implications mainly for sky cover and
temps. If it makes it into north central KS by this afternoon, the
warm front could lift north along the I-70 corridor and allow for
the low clouds to scatter out and temps to warm a little more. With
the warmer temps, the surface based instability could move a little
further north. Fortunately there does not appear to be a big
shortwave within the flow to spark deep moist convection, and the
forecast soundings keep a capping inversion over the warm sector.
Nevertheless did not feel confident enough to just go with drizzle
and maintained a mention of showers and thunderstorms through the
afternoon. At this point think areas along and north of I-70 will
remain overcast and cool with highs in the upper 50s along the NEB
state line to the mid 60s along I-70. Have temps warming to near 70
from EMP to Abilene where the warm front is more likely to move to.
Tonight timing of the next wave of precip is the main concern.
Models suggest a weak wave lifting out of the based of the closed
low to the west. This should cause the surface low pressure to
redevelop back to the southwest near the TX/OK panhandles and cause
the low level jet to back to the south again. The forecast shows
POPs increasing after midnight, but it appears the forcing comes
together mainly after 12Z. Lows should be mild for late October with
upper 50s and low 60s due to cloud cover and continued moisture
advection.
Wolters
.LONG TERM...(Wednesday through Monday)
Issued at 359 AM CDT TUE OCT 29 2013
Main upper trough will begin to lift out of the Rockies and into the
plains Wednesday and Wednesday night. Large scale ascent will be in
the increase through the day as the warm front remains situated
closer to the Nebraska border which is where the highest rainfall
amounts are expected. As the cold front begins to make an eastward
push across the CWA in the afternoon more showers and thunderstorms
are expected to form along and ahead of it...however the degree of
instability will remains uncertain with widespread cloud cover and
precip ahead of it during much of the day. Although feel the models
are overdoing the midday MLCAPE...still feel that 500-1000 J/kg are
not unreasonable with plenty of shear. Therefore...could see a brief
window in the late afternoon/early evening for strong to severe
convection along the front as high temps slowly edge up through the
upper 60s/near 70. As the front and axis of deeper moisture ahead of
it slowly shift eastward across the Wednesday night...so will the
higher pops...with likely chances limited to areas generally south
and east of the Kansas Turnpike after midnight.
As the cold front pushes southeast out of the county warning area
Thursday morning...precipitation chance will go with it as much
drier air in its wake as the main upper trough axis moves to the
east in the afternoon. Will carry a dry forecast for Thursday afternoon
as skies become mostly sunny all areas with highs in the lower 60s.
Will then maintain a dry forecast Friday and through the weekend as the
CWA remains in between the two troughs over the eastern and western
CONUS. Although highs in the upper 50s and lower 60s will be in the
rule Friday and Saturday...a return to southerly winds be Sunday and
warm advection ahead of the advancing western trough should allow
for highs to rebound back into the low to middle 60s on Sunday. The
next chance for showers arrives Monday into Monday night with the
approach of the upper trough in the Rockies.
&&
.AVIATION...(For the 12Z TAFs through 12Z Wednesday Morning)
Issued at 625 AM CDT TUE OCT 29 2013
With precip exiting to the east sooner than expected, will keep a
dry forecast beginning at 12Z. There may still be some drizzle
through the day, but latest OBS do not show drizzle immediately
behind the precip shield. Main concern is how far north and east
the warm front will lift this afternoon. The last several runs of
the RAP13 have been going back and forth in bringing the boundary
near the terminals. This will have a large impact on whether
IFR/LIFR conditions persist or if CIGS lift to MVFR. For now
stayed with persistence and maintained a IFR forecast since the
NAM and now the RAP keep the warm front just south. Precip could
move back into the terminals prior to 12Z Wed, but chances look
better after 12Z so have not included a mention at this time.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...Wolters
LONG TERM...63
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
816 PM EDT Wed Oct 30 2013
...Forecast Update...
Issued at 810 PM EDT Wed Oct 30 2013
Ongoing forecast for overnight still looks good with winds starting
to increase from the south and cloud cover keeping temperatures in
the 60s for most locations. Did get a spotter report of some lower
elevation fog in Cherokee Park this hour. This fog likely is caused
by a similar process to what creates sea fog, when the dewpoint
temperature becomes high enough to equal or exceed the water
temperature. Expect any of this fog to quickly dissipate however, as
winds pick up steadily through the night, helping to keep these
lower valleys more mixed.
The main concern continues to be the forecast for tomorrow. A couple
of things are certain. Precipitable water values will go up to near
record levels for this time of year, so available moisture is
plentiful. SREF surface pressure anomalies indicate that by 00Z
Friday, the pressure will be 3-4 standard deviations below normal
for this time of year. A strong wind field will develop in response
to this pressure change, as well as the fact that the surface low
will be continuing to deepen rapidly at this time. Forecast
soundings indicate winds at 850 mb at that time to range from 60-80
knots. Thus gradient winds, even under limited insolation/mixing by
late Thursday afternoon, should be enough to verify the current wind
advisory in place. In addition, given the low-level helicity in
place, will have to watch for breaks in the line of storms forecast
to come through, especially from roughly sunset to Midnight.
What is uncertain is how the mesoscale details will line up, and it
goes without saying that it is difficult to pin down mesoscale
details when we still are at the edge of the mesoscale time frame. A
look at the various high-res models we have that go out that far
indicate we should see numerous to widespread light to moderate rain
showers develop and continue through the day. Normally this type of
precip would kill off any instability before the front pushes
through. However, this is not a typical system. The 4km NAM and ARW
WRF both have a line develop closer to the front on the back edge of
the precip. SREF CAPE is between 100-200 ahead of this front, with
the NAM going with readings a little higher. Strong southerly winds
ahead of the line should help to bring in enough warm air to be able
to mix down some of these stronger winds aloft to allow for damaging
winds, even if the line ends up not producing lightning!
Needless to say, stay tuned for updates as the exact nature of the
event unfolds.
.SHORT TERM (Now through Thursday Night)...
Issued at 325 PM EDT Wed Oct 30 2013
Complex and high-impact forecast with a dynamic cold front and
possible SVR threat rolling through on Halloween night. This
afternoon the warm front is struggling to make any headway into
central Indiana, but southern Indiana and central Kentucky are
getting fairly well established in the warm sector, with temps
climbing into the 70s, except in the Bluegrass where the stratus has
held on and kept temps in the upper 60s. We have continued to see a
smattering of light showers from the Louisville Metro extending ESE
into the southern Bluegrass.
Expect most of the night to be dry as we remain in the warm sector.
Increasing S-SW winds just above the boundary layer will keep us
fairly mixy, and between that and warm advection, do not expect much
cooling. Lows will generally run in the lower 60s.
On Thursday a vigorous upper trof will eject out of the Panhandle
area, with a secondary surface low riding up the front just ahead of
it. Very strong wind fields over the Ohio Valley, with 850mb winds
eventually cranking up to 70+ kts, and 40 kt just 1000 feet off the
deck. Based on these wind fields, and raw model data showing 34 kt
in the boundary layer, believe there is sufficient gust potential to
warrant a Wind Advisory for the entire CWA in the late afternoon and
evening hours.
As for SVR potential, storm-relative helicity will be off the
charts, but the limiting factor will be instability. NAM12 forecast
soundings for 03Z Friday support a very narrow ribbon of instability
just ahead of the cold front, which is a fairly typical mode for
severe T-storms in the Ohio Valley. Expect something along the lines
of a leading stratiform QLCS, with a fast-moving main line right
along the cold front. Wind would be the main threat, but it`s
difficult to rule out a quick spin-up with so much shear. Worst
weather looks to be late in the evening as the front moves through.
Even ahead of the main line, it will not be a pleasant evening to be
outdoors, with a wind-driven rain and gusts near 40 mph.
Temp recovery on Thursday will be limited mainly by clouds and
precip. Even after starting off in the lower 60s, probably won`t
crack 70 north of the Western Kentucky and Bluegrass Parkways. Went
with a non-diurnal temp curve Thursday night, as temps will stay up
during the evening, and then fall quickly after a fropa around
midnight.
.LONG TERM (Friday through Wednesday)...
Issued at 300 PM EDT Wed Oct 30 2013
The start of the long term period will feature a broad trough across
the middle and eastern part of the CONUS, with an amplified ridge
just off the western U.S. coast. This pattern will be rather
progressive through the period, transitioning to southwesterly flow
aloft over the Ohio Valley by the middle of next week.
Conditions will quickly be drying out on Friday, behind the strong
storm system slated to affect the region Thursday (see short term
section above). Slightly cooler air will filter in behind a
departing cold front, but decent turbulent mixing should help to
offset the slightly cooler air a bit, keeping temperatures at least
in the middle 60s.
Another shortwave will dive southeast Friday night into Saturday,
helping to amplify the long wave trough over the Great Lakes and
into the Ohio Valley. Forecast soundings depict quite a bit of cold
air aloft as the core of this system passes overhead, helping to
induce some surface-based instability, mainly across the Northern
Bluegrass. Therefore, think some rather shallow, light showers will
be possible. With the trough amplifying overhead and the expected
cloud cover, temperatures will struggle to make it out of the lower
50s across the Northern Bluegrass, likely making for a rather damp
and raw day. Temperatures will be a bit warmer (in the upper 50s)
across southern KY where widespread clouds and rainfall look less
likely.
Conditions will then turn dry once again for the end of the weekend
into the first part of next week, with a slight warming trend
commencing. Temperatures on Sunday will be in the middle 50s,
warming into the lower 60s by Monday and Tuesday. The reason for
the warming trend will be an area of surface high pressure shifting
to the east, allowing for some return flow to develop in advance of
an approaching storm system. Guidance differences remain in the
timing of this system, but the trends discussed in the previous
discussion remain in place. The 30/00Z ECMWF remains a slow
outlier, with the 30/12Z GFS, GEFS, GEM, and NAEFS all being a bit
less amplified and quicker with the system. Therefore, will
continue to lean towards their consensus solution, which begins to
bring precipitation into areas west of I-65 by Tuesday afternoon.
It appears more widespread precipitation will affect the entire
region by Wednesday, as the upper-level flow transitions to
southwesterly, pumping more moisture up into the Ohio Valley.
&&
.AVIATION (00Z TAF Update)...
Issued at 720 PM EDT Wed Oct 30 2013
Warm front now well north of the region, so ceilings have improved
at all sites this hour. Next concern is low-level wind shear as a
nocturnal jet develops after 06Z. Latest RAP model forecast suggests
the shear to start around 1000 feet, so have lowered the shear to
this level in the TAFs. By mid morning these winds will start mixing
down. Will also see some showers, with the best chance for
restrictions at KSDF first, then later at the other sites. Pressure
gradient will tighten during the afternoon, as low pressure deepens
over the Great Lakes. Wind gusts by late afternoon and continuing
into the evening likely will reach at least 25-30 knots.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...WIND ADVISORY from 4 PM EDT /3 PM CDT/ Thursday to 1 AM EDT
/Midnight CDT/ Friday FOR KYZ023>043-045>049-053>057-
061>067-070>078-081-082.
IN...WIND ADVISORY from 4 PM EDT /3 PM CDT/ Thursday to 1 AM EDT
/Midnight CDT/ Friday FOR INZ076>079-083-084-089>092.
&&
$$
Update.........RJS
Short Term.....RAS
Long Term......KJD
Aviation.......RJS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
722 PM EDT Wed Oct 30 2013
...Updated Aviation Discussion...
.SHORT TERM (Now through Thursday Night)...
Issued at 325 PM EDT Wed Oct 30 2013
Complex and high-impact forecast with a dynamic cold front and
possible SVR threat rolling through on Halloween night. This
afternoon the warm front is struggling to make any headway into
central Indiana, but southern Indiana and central Kentucky are
getting fairly well established in the warm sector, with temps
climbing into the 70s, except in the Bluegrass where the stratus has
held on and kept temps in the upper 60s. We have continued to see a
smattering of light showers from the Louisville Metro extending ESE
into the southern Bluegrass.
Expect most of the night to be dry as we remain in the warm sector.
Increasing S-SW winds just above the boundary layer will keep us
fairly mixy, and between that and warm advection, do not expect much
cooling. Lows will generally run in the lower 60s.
On Thursday a vigorous upper trof will eject out of the Panhandle
area, with a secondary surface low riding up the front just ahead of
it. Very strong wind fields over the Ohio Valley, with 850mb winds
eventually cranking up to 70+ kts, and 40 kt just 1000 feet off the
deck. Based on these wind fields, and raw model data showing 34 kt
in the boundary layer, believe there is sufficient gust potential to
warrant a Wind Advisory for the entire CWA in the late afternoon and
evening hours.
As for SVR potential, storm-relative helicity will be off the
charts, but the limiting factor will be instability. NAM12 forecast
soundings for 03Z Friday support a very narrow ribbon of instability
just ahead of the cold front, which is a fairly typical mode for
severe T-storms in the Ohio Valley. Expect something along the lines
of a leading stratiform QLCS, with a fast-moving main line right
along the cold front. Wind would be the main threat, but it`s
difficult to rule out a quick spin-up with so much shear. Worst
weather looks to be late in the evening as the front moves through.
Even ahead of the main line, it will not be a pleasant evening to be
outdoors, with a wind-driven rain and gusts near 40 mph.
Temp recovery on Thursday will be limited mainly by clouds and
precip. Even after starting off in the lower 60s, probably won`t
crack 70 north of the Western Kentucky and Bluegrass Parkways. Went
with a non-diurnal temp curve Thursday night, as temps will stay up
during the evening, and then fall quickly after a fropa around
midnight.
.LONG TERM (Friday through Wednesday)...
Issued at 300 PM EDT Wed Oct 30 2013
The start of the long term period will feature a broad trough across
the middle and eastern part of the CONUS, with an amplified ridge
just off the western U.S. coast. This pattern will be rather
progressive through the period, transitioning to southwesterly flow
aloft over the Ohio Valley by the middle of next week.
Conditions will quickly be drying out on Friday, behind the strong
storm system slated to affect the region Thursday (see short term
section above). Slightly cooler air will filter in behind a
departing cold front, but decent turbulent mixing should help to
offset the slightly cooler air a bit, keeping temperatures at least
in the middle 60s.
Another shortwave will dive southeast Friday night into Saturday,
helping to amplify the long wave trough over the Great Lakes and
into the Ohio Valley. Forecast soundings depict quite a bit of cold
air aloft as the core of this system passes overhead, helping to
induce some surface-based instability, mainly across the Northern
Bluegrass. Therefore, think some rather shallow, light showers will
be possible. With the trough amplifying overhead and the expected
cloud cover, temperatures will struggle to make it out of the lower
50s across the Northern Bluegrass, likely making for a rather damp
and raw day. Temperatures will be a bit warmer (in the upper 50s)
across southern KY where widespread clouds and rainfall look less
likely.
Conditions will then turn dry once again for the end of the weekend
into the first part of next week, with a slight warming trend
commencing. Temperatures on Sunday will be in the middle 50s,
warming into the lower 60s by Monday and Tuesday. The reason for
the warming trend will be an area of surface high pressure shifting
to the east, allowing for some return flow to develop in advance of
an approaching storm system. Guidance differences remain in the
timing of this system, but the trends discussed in the previous
discussion remain in place. The 30/00Z ECMWF remains a slow
outlier, with the 30/12Z GFS, GEFS, GEM, and NAEFS all being a bit
less amplified and quicker with the system. Therefore, will
continue to lean towards their consensus solution, which begins to
bring precipitation into areas west of I-65 by Tuesday afternoon.
It appears more widespread precipitation will affect the entire
region by Wednesday, as the upper-level flow transitions to
southwesterly, pumping more moisture up into the Ohio Valley.
&&
.AVIATION (00Z TAF Update)...
Issued at 720 PM EDT Wed Oct 30 2013
Warm front now well north of the region, so ceilings have improved
at all sites this hour. Next concern is low-level wind shear as a
nocturnal jet develops after 06Z. Latest RAP model forecast suggests
the shear to start around 1000 feet, so have lowered the shear to
this level in the TAFs. By mid morning these winds will start mixing
down. Will also see some showers, with the best chance for
restrictions at KSDF first, then later at the other sites. Pressure
gradient will tighten during the afternoon, as low pressure deepens
over the Great Lakes. Wind gusts by late afternoon and continuing
into the evening likely will reach at least 25-30 knots.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...WIND ADVISORY from 4 PM EDT /3 PM CDT/ Thursday to 1 AM EDT
/Midnight CDT/ Friday FOR KYZ023>043-045>049-053>057-
061>067-070>078-081-082.
IN...WIND ADVISORY from 4 PM EDT /3 PM CDT/ Thursday to 1 AM EDT
/Midnight CDT/ Friday FOR INZ076>079-083-084-089>092.
&&
$$
Short Term........RAS
Long Term.........KJD
Aviation..........RJS
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1030 PM CDT WED OCT 30 2013
.DISCUSSION...
UPDATED MOST GRIDDED ELEMENTS FOR THE NEXT 36 HRS OR SO. WHILE
MOST MODELS IN GENERAL DID FAIRLY POORLY WITH THE RAINFALL TODAY
AND THIS EVENING...THE HRRR HAS DONE A DECENT JOB DEPICTING
CONVECTION THIS EVENING GRADUALLY DECREASING IN INTENSITY AND
LIFTING NORTHWARD. WHLIE THE SPIGOT MAY NOT SHUT OFF
COMPLETELY...IT APPEARS THAT MOST AREAS SHOULD GET A BREAK FROM
HEAVY RAINFALL DURING THE OVERNIGHT HOURS...A MUCH NEEDED ONE FOR
PARTS OF EAST TEXAS INTO WEST CENTRAL LOUISIANA WHERE ESTIMATES OF
4 TO 6 INCHES WITH LOCALLY HIGHER AMOUNTS HAVE FALLEN. THIS IS
SQUARELY WITHIN THE FLASH FLOOD WATCH AREA...AND WITH ADDITIONAL
AMOUNTS OF 2 TO 4 INCHES...LOCALLY HIGHER...EXPECTED TO FALL
TOMORROW...HAVE EXTENDED THE WATCH THROUGH TOMORROW EVENING. THE
HRRR SUGGESTS A BAND OF HEAVY PCPN WILL BE ONGOING OR JUST
ENTERING EAST TEXAS BY DAYBREAK...AND SLOWLY PROGRESS EAST THROUGH
THE REGION ON THURSDAY INTO THURSDAY NIGHT.
A MODEST TO HIGH SHEAR/HELICITY AND LOW TO MODEST CAPE/INSTABILITY
ENVIRONMENT IS EXPECTED TO BE IN PLACE TOMORROW...AND SPC HAS
THE ENTIRE REGION OUTLINED IN SLIGHT RISK FOR SEVERE
THUNDERSTORMS...WITH TORNADOES/DAMAGING WINDS THE PRIMARY HAZARDS.
13
&&
.PREV DISCUSSION... /ISSUED 653 PM CDT WED OCT 30 2013/
AVIATION UPDATE...REGARDING 00Z TAF ISSUANCE. WIDESPREAD SHOWERS
AND A FEW THUNDERSTORMS OVER CENTRAL LOUISIANA INTO INTERIOR
SOUTHEAST TEXAS WILL CONTINUE TO ADVANCE NORTHEAST WITH RAIN
CHANCES THEN DIMINISHING. SHOWER AND THUNDERSTORM ACTIVITY WILL
RAMP UP AGAIN GOING THROUGH THURSDAY FROM WEST TO EAST AS A STRONG
COLD FRONT APPROACHES AND ADVANCES ACROSS THE AREA DURING THE LATE
AFTERNOON AND EVENING. UNTIL THE FROPA...A STRONG AND GUSTY
SOUTHERLY FLOW WILL CONTINUE...WITH MVFR CEILINGS OVERSPREADING
THE ENTIRE FORECAST AREA.
MARCOTTE
PREV DISCUSSION... /ISSUED 438 PM CDT WED OCT 30 2013/
DISCUSSION...
SHOWERS AND THUNDERSTORMS HAVE BEEN TRAINING ACROSS SOUTHEAST
TEXAS AND SOUTHWEST LOUISIANA NORTH OF THE I-10 CORRIDOR THIS
AFTERNOON. STORM TOTALS REPORTED HAVE RANGED FROM ONE TO FOUR
INCHES. THIS AREA OF SHOWERS IS ASSOCIATED WITH A FRONTAL BOUNDARY
THAT IS CURRENTLY MOVING INTO CENTRAL TEXAS. TEMPS TODAY HAVE
CLIMBED INTO THE LWR 80S OUTSIDE OF RAIN COOLED AREAS ON SOUTHEAST
WINDS.
AS A RESULT OF STRONG SOUTHEAST WINDS TIDES ALONG THE COAST ARE
RUNNING ONE TO TWO FEET ABOVE NORMAL. WINDS SOUTH OF THE I-10
CORRIDOR HAVE BEEN RUNNING AROUND 14 TO 18 MPH WITH GUSTS ABOVE
20 MPH AND THIS WILL CONTINUE INTO THE EVENING HOURS...BUT WILL
REMAIN BELOW WIND ADVISORY.
THIS ACTIVITY WILL CONTINUE INTO TONIGHT AND TOMORROW UNTIL THE
FRONTAL PASSAGE WHICH IS EXPECTED LATE THURSDAY NIGHT INTO EARLY
FRIDAY MORNING. THERE WILL BE A SMALL THREAT THAT A FEW STORMS MAY
BECOME SEVERE.
ALL THIS ACTIVITY SHOULD BE OUT OF THE REGION BEFORE THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 72 80 57 78 / 70 100 100 10
KBPT 74 80 59 77 / 70 100 70 10
KAEX 70 79 56 78 / 100 100 70 10
KLFT 72 81 64 78 / 20 100 100 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...FLASH FLOOD WATCH THROUGH THURSDAY EVENING FOR ALLEN-BEAUREGARD-
RAPIDES-VERNON.
COASTAL FLOOD ADVISORY UNTIL 7 PM CDT THURSDAY FOR EAST CAMERON-
IBERIA-ST. MARY-VERMILION-WEST CAMERON.
TX...FLASH FLOOD WATCH THROUGH THURSDAY EVENING FOR HARDIN-NORTHERN
JASPER-NORTHERN NEWTON-SOUTHERN JASPER-SOUTHERN NEWTON-
TYLER.
COASTAL FLOOD ADVISORY UNTIL 7 PM CDT THURSDAY FOR JEFFERSON.
GM...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THURSDAY FOR COASTAL WATERS
FROM CAMERON LA TO HIGH ISLAND TX OUT 20 NM-COASTAL WATERS
FROM INTRACOASTAL CITY TO CAMERON LA OUT 20 NM-COASTAL
WATERS FROM LOWER ATCHAFALAYA RIVER TO INTRACOASTAL CITY LA
OUT 20 NM-WATERS FROM INTRACOASTAL CITY TO CAMERON LA FROM
20 TO 60 NM-WATERS FROM CAMERON LA TO HIGH ISLAND TX FROM
20 TO 60 NM-WATERS FROM LOWER ATCHAFALAYA RIVER TO
INTRACOASTAL CITY LA FROM 20 TO 60 NM.
&&
$$
AREA FORECAST DISCUSSION
NWS CARIBOU ME
350 PM EDT TUE OCT 29 2013
.SYNOPSIS...
HIGH PRESSURE WILL BUILD OVER THE AREA TONIGHT AND WILL MOVE EAST
OF THE REGION ON THURSDAY. LOW PRESSURE WILL APPROACH LATE THURSDAY
AND LIFT NORTH OF THE STATE THURSDAY NIGHT INTO FRIDAY.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
MAJOR CHALLENGE WILL BE THE CLOUDS ACROSS THE NORTHERN 3RD OF THE
CAW AND TEMPERATURES.
19Z VISIBLE SATL IMAGERY AND METARS SHOWED THE THICKEST CLOUD
COVER ACROSS THE N AND W. FURTHER S AND E, MOSTLY CLEAR SKIES.
THE LATEST 19Z LAPS/RAP SOUNDINGS SHOWED LLVL MOISTURE TRAPPED
BELOW 850 MBS W/DRY AIR ALOFT. CLOUDS ACROSS THE NORTH AND WEST
WILL DISSIPATE LATER THIS EVENING AS DRIER AIR WORKS ITS WAY
THROUGH THE COLUMN AS SHOWN BY THE RAP BY 03Z LEADING TO CLEARING
AND WINDS DECOUPLING. A S/WV SHOWING IN THE UPPER LEVELS IS FCST
TO MOVE ACROSS CENTRAL AND SOUTHERN MAINE LATER TONIGHT INTO
WEDNESDAY. MOST OF THE MOISTURE ASSOCIATED W/THIS FEATURE IS FROM
700-500MBS AND THIS WILL BE MOST PROMINENT ACROSS THE DOWNEAST AND
COASTAL AREAS. THIS WILL AID IN CAPPING TEMPERATURES OVERNIGHT BY
06Z WHILE TEMPERATURES FURTHER N AND W WILL DROP OFF SIGNIFICANTLY
DUE TO THE CLEAR SKIES AND WINDS DROPPING OFF BELOW 6 MPH.
TEMPERATURES BY EARLY WEDNESDAY MORNING ARE FCST TO BE IN THE
UPPER TEENS TO AROUND 20 ACROSS THE N AND W WHILE LOW TO MID 20S
WILL BE COMMON IN THE CENTRAL AND DOWNEAST REGION. THE COAST WILL
BE A TAD WARMER AS HIGH CLOUDS MOVE IN W/EXPECTED OVERNIGHT LOWS
IN THE UPPER 20S.
IN REGARDS TO THE S/WV MENTIONED ABV, THE LATEST RAP AND NAM
INDICATED SOME WEAK MID LEVEL FORCING W/SOME LIGHT PRECIP EDGING
THE COAST AND OFFSHORE WATERS. THE 12Z GFS AND GEM SHOWS THIS TO
SOME EXTENT. THE 12Z UA DID SHOW A 30-35KT JETLET AT 700MBS
ASSOCIATED W/THIS FEATURE AND THEREFORE ADDED 20-30% FOR LIGHT RAIN
SHOWERS BY WEDNESDAY MORNING INTO EARLY AFTERNOON FOR THE IMMEDIATE
COAST. THERE IS SOME CONCERN THAT THERE COULD BE SOME SPOTTY
LIGHT FREEZING PRECIP BUT ATTM CONFIDENCE TO LOW ON THIS AND
DECIDED TO KEEP THE WX ELEMENT AS SHOWERS W/THE BULK OF THE PRECIP
ARRIVING NEAR OR AFTER 12Z W/TEMPERATURES WARMING. DUE TO
DEWPOINTS BEING IN THE UPPER TEENS AND LOWER 20S, WOULD NOT BE
SURPRISED IF SOME BRIEF FLAKES OR EVEN SLEET OCCURS AT THE ONSET
OF ANY PRECIP. THE EVENING CREW CAN ASSESS THIS FURTHER TONIGHT.
SKIES ARE EXPECTED TO BECOME AT LEAST PARTLY SUNNY AND TEMPERATURES
ARE FCST TO WARM WELL INTO THE 30S ACROSS THE N AND W AND MID TO
UPPER 40S CENTRAL AND DOWNEAST.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
INTENSE LOW PRESSURE MOVES INTO THE GREAT LAKES THEN INTO QUEBEC
PROVINCE FRIDAY. AT THE SAME TIME STRONG HIGH PRESSURE WILL MOVE
EAST INTO THE ATLANTIC DURING THE DAY THURSDAY. WILL USE A BLEND
OF THE NAM12..GFS40..SREF AND ECMWF FOR POPS AND QPF. FOR
TEMPERATURE WILL USE THE CONSENSUS RAW BLEND. FOR WINDS HAVE USED
THE MOSG25.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
A STRONG COLD FRONT BEHIND THIS SYSTEM WILL MOVE THROUGH THE
REGION FRIDAY NIGHT INTO SATURDAY. LOW PRESSURE IS EXPECTED TO
DEVELOP ALONG THIS COLD FRONT SOUTH OF NEW ENGLAND LATE SATURDAY
THEN MOVE TO THE NORTHEAST. STRONG HIGH PRESSURE WILL BUILD IN
FROM THE WEST SUNDAY THEN CREST OVER THE REGION MONDAY. HAVE USED
THE SUPPER BLEND TO INITIALIZE ALL GRIDS. WILL ADJUST WIND GUSTS
USING 150 PERCENT OF THE SUSTAINED WIND SPEED.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
NEAR TERM: A BRIEF PERIOD OF MVFR FOR FAR NORTHERN TERMINALS SUCH
AS KCAR/KFVE AND KPQI THIS EVENING AND THEN VFR. FROM KHUL TO
KBHB, IT LOOKS LIKE VFR RIGHT INTO WEDNESDAY.
SHORT TERM: EXPECT VFR CONDITIONS WEDNESDAY NIGHT. IFR CONDITIONS
EXPECTED THURSDAY AND FRIDAY. MVFR CONDITIONS EXPECTED SATURDAY.
VFR CONDITIONS EXPECTED MONDAY.
&&
.MARINE...
NEAR TERM: NO HEADLINES AS CONDITIONS WILL BE BELOW SCA
THRESHOLDS. DECIDED TO FOLLOW THE SHORT TERM`S LEAD USING A BLEND
OF THE NAM12 AND GFS40 FOR THE SUSTAINED WINDS WHICH SHOW AN INCREASE
TO 10-15 KTS WEDNESDAY AFTERNOON. THIS IS IN RESPONSE TO THE S/WV
MOVING ACROSS THE REGION. WAVE HEIGHTS ARE FCST TO BE NO HIGHER THAN
3 FT USING THE SWAN GUIDANCE TO INITIALIZE.
SHORT TERM: FOR SUSTAINED WINDS HAVE USED A BLEND OF THE NAM12
...GFS40 AND ECMWF OUT TO 1200Z FRIDAY THEN TRANSITION TO THE
SUPPER BLEND WINDS. WILL LOWER SUSTAINED WIND SPEED THURSDAY NIGHT
BY 10 PERCENT TO ACCOUNT FOR BOUNDARY LAYER CONDITIONS. FOR WIND
GUST SPEED HAVE USED 110 PERCENT OF THE SUSTAINED WIND. FOR WAVES:
EXPECT COMBINED SEAS ...MOSTLY COMPOSED OF LOCAL WIND WAVE TO
SUBSIDE TO 1-2 FEET WEDNESDAY NIGHT. SOUTHERLY FETCH DEVELOPS FROM
GULF OF MAINE AND EXTENDS TO SOUTH THURSDAY IN RESPONSE TO DEEP LOW
PRESSURE MOVING INTO THE GREAT LAKES. EXPECT SOUTHERLY WAVE SYSTEM
TO BUILD TO 15 FEET/9-10 SECONDS BY MID DAY FRIDAY. LONG PERIOD
SOUTHERLY WAVE GROUP WILL SUBSIDE SLOWLY SATURDAY AND SUNDAY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HEWITT
SHORT TERM...MIGNONE
LONG TERM...MIGNONE
AVIATION...HEWITT/MIGNONE
MARINE...HEWITT/MIGNONE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
804 PM EDT WED OCT 30 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 420 PM EDT WED OCT 30 2013
WV IMAGERY AND RAP ANALYSIS SHOWING A BROAD UPPER TROUGH OVER THE
ROCKIES AND A WEAK UPPER RIDGE SHIFTING EAST ACROSS THE AREA. AS
THIS UPPER RIDGE SHIFTS EAST LATE THIS AFTERNOON AND EARLY THIS
EVENING...AREA WILL COME UNDER INCREASING SOUTHWESTERLY FLOW FROM
THE UPPER TROUGH...PUSHING OUR PWAT VALUES FROM 0.75IN (WHICH IS
STILL 150 PERCENT OF NORMAL) TO OVER 1.0IN (OR 200-225 PERCENT OF
NORMAL) OVER THE EASTERN CWA TONIGHT. THAT SOUTHWESTERLY FLOW ALOFT
WILL ALSO LEAD TO BROAD WARM AIR ADVECTION THROUGH THE
NIGHT...ESPECIALLY OVER THE CENTRAL AND EASTERN CWA. AT THE
SURFACE...A LOW THAT HAS DEVELOPED NEAR THE TEXAS PANHANDLE WILL BE
THE MAIN CONCERN FOR THE WEATHER FOR TOMORROW AFTERNOON INTO
TOMORROW NIGHT AS IT MOVES INTO THE GREAT LAKES REGION. BUT BEFORE
THAT OCCURS...AN ELONGATED SURFACE TROUGH WILL STRETCH NORTHEAST
FROM THAT LOW AND ACROSS UPPER MICHIGAN AND LAKE SUPERIOR TONIGHT.
THAT SURFACE TROUGH WILL COMBINE WITH THE SEVERAL SHORTWAVES MOVING
NORTHEAST FROM THE CENTRAL PLAINS (AND PRODUCING THE AREAS OF
CONVECTION AROUND SOUTHEAST IOWA AND NORTHWEST ILLINOIS)...ALONG
WITH THE BROAD WARM AIR ADVECTION AND MOISTURE TRANSPORT TO PRODUCE
SCATTERED SHOWERS WEST AND NUMEROUS/WIDESPREAD SHOWERS EAST TONIGHT.
AN INITIAL BAND OF RAIN SHOWERS AND DRIZZLE HAS BEEN MOVING
EAST-NORTHEAST ACROSS UPPER MICHIGAN THIS AFTERNOON AND EXPECT THAT
TO CONTINUE OVER THE NEXT COUPLE OF HOURS. WITH THE WARM AIR
ADVECTION AND MOISTURE TRANSPORT BEING VERY BROAD AND
COVERING MUCH OF THE CWA...IT/S HARD TO PIN DOWN AREAS WHERE THE
SHOWERS WILL BE LOCATED AND WHEN THEY WILL OCCUR. FEEL THAT THE
COVERAGE WILL LIKELY BE SCATTERED IN NATURE THROUGH THE
EVENING...AND THEN RAMP UP (ESPECIALLY OVER THE CENTRAL/EASTERN
CWA) TOWARDS MIDNIGHT AND THROUGH THE OVERNIGHT HOURS...AS THE
SHORTWAVE ENERGY IN IOWA MOVES THROUGH THE AREA. SINCE THERE IS
PLENTY OF LOW LEVEL MOISTURE...DID ADD MENTION OF PATCHY/AREAS OF
DRIZZLE FOR LATE THIS AFTERNOON AND INTO THE EVENING HOURS UNTIL
THE MORE WIDESPREAD PRECIPITATION ARRIVES. HIGHER RESOLUTION MODELS
SEEM TO BE STRUGGLING WITH THIS BROAD WAA...BUT SEEM TO FOLLOW THAT
SIMILAR IDEA...ALTHOUGH A FEW SHOW THE COVERAGE TO BE LACKING. IF
THE SHOWERS DEVELOP AS EXPECTED...THERE COULD BE SOME RUMBLES OF
THUNDER OVERNIGHT AS THERE IS A LITTLE BIT OF MUCAPE TONIGHT (50-150
J/KG). IN ADDITION...850-700/500MB LAPSE RATES DO INCREASE TO
6.5C/KM...SO CAN/T COMPLETELY RULE OUT SOME RUMBLES OF THUNDER AS
THE SHOWERS MOVE THROUGH. IF CONFIDENCE WAS HIGHER ON SHOWER
LOCATION AND INTENSITY...WOULD ADD IN ISOLATED THUNDER AND WILL
PASS ALONG TO THE EVENING SHIFT ON A POSSIBLE ADDITION.
ONCE THE SHORTWAVE MOVE THROUGH...HAVE SHOWN A DRYING TREND TO THE
POPS OVER THE WEST THIRD LATE TONIGHT. WITH WINDS SHIFTING TO THE
WEST OR EVEN WEST-NORTHWEST...THINK THE UPSLOPE DIRECTION TO THE
WINDS WILL PRODUCE SOME LIGHT DRIZZLE.
HAVE CONTINUED THE MENTION OF FOG FOR TONIGHT...BUT SPREAD INTO
THIS AFTERNOON AND EXPANDED TO BE WIDESPREAD OVER THE CENTRAL
HIGHER TERRAIN. WITH THE ABUNDANT MOISTURE AROUND AND LOW CLOUDS
AND FOG ALREADY IN PLACE...THINK THAT IS REASONABLE. AFTER THE
SHOWERS MOVE THROUGH...COULD SEE VISIBILITIES FALL TOWARDS
1/4-1/2MI IN THE CENTRAL CWA AND DID ADD A MENTION OF PATCHY DENSE
FOG.
FOR THURSDAY...WITH THE SHORTWAVES AND DEEPER MOISTURE PULLING
NORTHEAST AND AWAY FROM THE CWA THURSDAY MORNING...SHOULD SEE A
DIMINISHING TREND IN THE PRECIP FROM WEST TO EAST. WITH DRIER AIR
MOVING IN ALOFT AND PLENTY OF LOW LEVEL MOISTURE...EXPECT IT TO BE
A DREARY DAY OVER MUCH OF UPPER MICHIGAN. LOW CLOUDS WILL CONTINUE
TO COVER THE AREA AND WILL CONTINUE AREAS/PATCHY FOG OVER THE
HIGHER TERRAIN LOCATIONS AND IN AREAS FAVORED BY LIGHT
WEST-NORTHWESTERLY FLOW OVER THE WEST. HAVE ALSO CONTINUED LIGHT
RAIN SHOWERS OR DRIZZLE FOR THAT PERIOD OVER THE WESTERN CWA.
HEADING INTO THE AFTERNOON...THE SHORTWAVE AND PV ANOMALY WILL
EJECT OUT FROM THE SOUTHERN PLAINS AND INTENSIFY THE LOW AS IT
PULLS NORTHEAST TOWARDS THE GREAT LAKES REGION. MODELS HAVE BEEN
VARIABLE ON THE TRACK OF THE LOW...WITH A CONSENSUS NOW SHOWING IT
LOCATED OVER CENTRAL LAKE MICHIGAN AT 00Z. BUT THEY HAVE BEEN
CONSISTENT ON IT RAPIDLY DEEPENING THURSDAY NIGHT AS IT MOVES
THROUGH THE GREAT LAKES. THIS TRACK GREATLY INFLUENCES THE
PRECIPITATION CHANCES OVER THE SOUTHEASTERN 1/3RD OF THE CWA AND
HAVE FOLLOWED A GENERAL CONSENSUS WITH POPS INCREASING IN THAT AREA
TOWARDS LATE AFTERNOON. OVER THE REST OF THE AREA...THE
CLOUDY/DRIZZLY CONDITIONS WILL CONTINUE.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 420 PM EDT WED OCT 30 2013
THE MAIN FOCUS THIS FORECAST PERIOD WILL BE THE DEVELOPING LOW
PRESSURE OVER THE CENTRAL PLAINS...FORECAST TO MOVE INTO UPPER
MICHIGAN THURSDAY-FRIDAY. MODELS ARE GENERALLY IN DISAGREEMENT AS TO
THE LOWS POSITION BY 00-6Z FRIDAY. ALTHOUGH THE DIFFERENCES ARE
SLIGHT...THE LOCATION OF HIGHEST QPF WILL SHIFT DEPENDING ON THE LOW
TRACK. IF THE NAM VERIFIES...PRECIPITATION AMOUNTS WILL DIFFER
GREATLY FROM WHAT IS IN THE FORECAST NOW.
GENERALLY...THE 12Z GFS WRAPS THE SFC LOW UP SOONER THAN THE 00Z
ECMWF/12Z NAM RUN. THE LOW TRACKS FROM NORTHERN LAKE MICHIGAN AT 00Z
TO NORTHERN LAKE HURON BY 06Z...DEEPENING FROM 989MB TO 982MB. THE
NAM ON THE OTHER HAND...HAS A 992MB LOW OVER SOUTHERN LAKE MICHIGAN
AT 00Z...WITH A TROUGH EXPANDING NORTHWARD ACROSS THE LAKE. BY
6Z...THIS LOW DEEPENS TO 982MB OVER SAGINAW BAY. AT 00Z...THE 00Z
ECMWF POSITIONS A CLOSED LOW OVER CENTRAL LAKE MICHIGAN...A SORT OF
COMPROMISE BETWEEN THE GFS/NAM...BUT THEN ALIGNS ITSELF MORE
FAVORABLY WITH THE GFS BY 6Z...WITH THE LOW OVER NORTHERN LAKE
HURON. THE 12Z REGIONAL GEM BASICALLY IS A COMPROMISE BETWEEN THE
ECMWF/NAM...SO THIS WAS THE PRIMARY MODEL USED TO CREATE THE
WINDS/POPS FOR THIS FORECAST. THE GFS TRACK SEEMS TO BE TOO FAR
NORTH...AND IT STARTS TRENDING SOUTHWARD IN THE 6Z TIME
FRAME...WHICH MAKES ME FEEL MORE CONFIDENT USING THE GEM SOLUTION.
EXPECT LL FGEN BAND ASSOCIATED WITH A TROWAL-LIKE FEATURE TO SET UP
ACROSS EASTERN UPPER MICHIGAN/NEAR THE LAKE MI SHORE FROM 00Z-06Z.
EXPECT PRECIPITATION CHANCES TO BE GREATEST ALONG THIS AXIS. HIGHER
QPF AMOUNTS WERE LIMITED TO THE LAKE MICHIGAN SHORELINE...AS THIS IS
WHERE THE MID-UPPER LEVEL SUPPORT IS MAXIMIZED. MOISTURE WITH THIS
SYSTEM IS ABUNDANT...AS PWATS RISE TO AROUND 200 PERCENT OF
NORMAL...WITH THE HIGHEST VALUES ACROSS THE CENTRAL AND EAST.
THANKFULLY...850MB TEMPS ARE AROUND 0-9C DURING THIS EVENT...SO NO
SNOW IS EXPECTED. OVERALL TEMPERATURES/THICKNESSES ACROSS THE CWA
REMAIN SUPPORTIVE OF A RAIN EVENT THROUGH 12Z FRIDAY.
ONCE WE GET CLOSER TO THE LATE FRIDAY MORNING-SATURDAY TIME
FRAME...850MB TEMPS BECOME COOLER...AROUND -3 TO -6 AT THE
WORST...AND MAINLY OUT WEST. A SECONDARY SHORTWAVE ALOFT MOVES
THROUGH FRIDAY NIGHT AS WELL...WHICH WILL SUPPORT RAIN/SNOW SHOWERS
INLAND FROM THE LAKES DURING THIS TIME. OVERALL...WITH
NORTH-NORTHWESTERLY WINDS AND A LINGERING UPPER LEVEL
TROUGH/CYCLONIC FLOW...EXPECT THE LAKE EFFECT RAIN/SNOW SHOWERS TO
REMAIN THROUGH 06-12Z SUN...THOUGH THEY WILL TAPER OFF WITH TIME AS
THE FLOW GRADUALLY BECOMES MORE ANTICYCLONIC AND MOISTURE DWINDLES.
THE WEAK SFC HIGH PRESSURE WILL FINALLY MOVE IN SUNDAY...BRINGING A
BREAK TO THE MORE ACTIVE WEATHER.
FOR THE EXTENDED TIME FRAME...LOW PRESSURE DEVELOPS ACROSS THE
CENTRAL AND NORTHERN PLAINS AND MOVES INTO ONTARIO. THE ECMWF PULLS
THIS SURFACE LOW FURTHEST NORTH OVER JAMES BAY...AND THE GFS KEEPS
IT OVER NORTHERN ONTARIO. EITHER WAY...UPPER MICHIGAN WILL BE IN THE
SOUTHERLY FLOW AHEAD OF THE LOW...AND 850MB TEMPS REMAIN ABOVE ZERO
FOR THE MOST PART. EXPECT MAINLY RAIN CHANCES AS A RESULT...THOUGH
OVERNIGHT/MORNING COOLER TEMPERATURES COULD RESULT IN A RAIN/SNOW
MIX FOR SOME AREAS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 757 PM EDT WED OCT 30 2013
WARM MOIST AIR STREAMING NORTHEAST ACROSS UPPER MICHIGAN THIS
TONIGHT ALONG AN ELONGATED SURFACE TROUGH WILL LEAD TO VLIFR
CONDITIONS WITH LOW CLOUDS AND DENSE FOG AT CMX/SAW INTO THU MORNING.
THERE MAY BE SOME PERIODS OF IMPROVED VSBY TO 1-3SM AS LIGHT RAIN
SHOWERS MOVE THROUGH THE AREA. A DOWNSLOPE SRLY WIND AT IWD WILL
LIMIT FOG POTENTIAL EVEN WITH IFR CIGS PREVAILING.
ALTHOUGH THE RAIN WILL DEPART FROM WEST TO EAST LATE TONIGHT INTO
EARLY TOMORROW MORNING...THE WINDS TURNING TO THE WEST/NORTHWEST
WILL FAVOR DRIZZLE FOR KCMX/KIWD AND THE UPSLOPE FLOW WILL KEEP
CEILINGS LOW. AT KSAW...THE WINDS WILL STAY OUT OF THE SOUTHWEST
THROUGH MUCH OF THE MORNING AND EXPECT FOG TO BE THE MAIN FACTOR
IMPACTING THE VISIBILITY.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 420 PM EDT WED OCT 30 2013
A LOW PRESSURE SYSTEM DEVELOPING NEAR THE TEXAS PANHANDLE TODAY
WILL BE THE MAIN WEATHER MAKER FOR THE FORECAST PERIOD. THIS LOW
WILL SLIDE A TROUGH NORTHEAST INTO LAKE SUPERIOR TONIGHT AND WILL
LEAD TO WINDS INCREASING OUT OF THE SOUTH TO 20KTS OVER THE
EASTERN HALF OF THE LAKE. WINDS ARE THEN EXPECTED TO WEAKEN
THURSDAY MORNING AS THE LOW INTENSIFIES AND QUICKLY MOVES NORTHEAST
TO CENTRAL LAKE MICHIGAN BY THURSDAY EVENING. AS THE LOW FURTHER
INTENSIFIES AND MOVES ACROSS LAKE HURON ON THURSDAY NIGHT...EXPECT
NORTH-NORTHWESTERLY WINDS TO INCREASE THURSDAY NIGHT INTO FRIDAY
MORNING. THE STRENGTH OF THE WINDS WILL DEPEND ON THE EXACT TRACK OF
THE LOW...BUT THE CURRENT THINKING IS GUSTS UP TO 30KTS OVER THE FAR
SOUTHEASTERN PART OF LAKE SUPERIOR AND TO 20-25KTS ELSEWHERE. IF THE
LOW TRACKS A LITTLE FARTHER NORTH...COULD SEE SOME GALES OVER THE
SOUTHEAST PART OF THE LAKE.
THE LOW WILL CONTINUE NORTHEAST FRIDAY NIGHT AND SATURDAY...BUT
WILL LEAVE A SURFACE TROUGH OVER THE UPPER GREAT LAKES REGION
THROUGH SATURDAY EVENING. WINDS DURING THIS PERIOD SHOULD STAY
BELOW 20KTS. WEAK HIGH PRESSURE WILL BUILD IN FOR SUNDAY AND LEAD TO
WINDS FALLING BELOW 15KTS BEFORE SOUTHERLY FLOW INCREASES AHEAD OF A
LOW MOVING NORTHEAST THROUGH ONTARIO ON MONDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...MCD
AVIATION...JLB
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
118 PM EDT TUE OCT 29 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 426 AM EDT TUE OCT 29 2013
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A NW FLOW ALF OVER
THE UPR GREAT LKS BTWN UPR TROF CENTERED OVER ERN HUDSON BAY AND A
RDG IN THE PLAINS. SPRAWLING SFC HI PRES/DRY AIRMASS WITH PWAT AOB
0.25 INCH IS CENTERED OVER THE UPR LKS...BRINGING QUIET WX TO THE
CWA. ALTHOUGH SOME HI CLDS IN THE RRQ OF A 100KT H3 JET MAX ARE
STREAMING INTO THE CWA...TEMPS HAVE FALLEN SHARPLY AND INTO THE
TEENS OVER INTERIOR LOCATIONS WITH LIGHT WINDS UNDER THE SFC HI.
MORE SC DOES LINGER OVER THE E NEAR LK SUP WITH LLVL NW FLOW E OF
THE HI CENTER...AND THESE CLDS HAVE RESTRICTED THE DIURNAL TEMP FALL
IN THIS AREA. LOOKING TO THE W...DESPITE SOME DRY LLVL AIR SHOWN ON
THE 00Z ABERDEEN SDAKOTA AND BISMARK RAOBS...THERE IS AN AREA OF -SN
OVER SRN NDAKOTA AND NRN SDAKOTA. THE PRIMARY FORCING MECHANISMS
APPEAR TO BE SOME ISENTROPIC ASCENT ON THE 295-300K SFCS AS WELL AS
A BAND OF H7-75 FGEN UNDER UPR DVGC IN RRQ OF THE H3 JET MAX. AN
UPSLOPE SFC E WIND ALSO APPEARS TO BE AIDING IN THE LLVL MOISTENING
DESPITE THE LLVL DRY AIR FEED OUT OF THE E ON THE SRN FLANK OF THE
SFC HI PRES RDG.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE PCPN CHCS OVER UPR MI
RELATED TO THE UPSTREAM DISTURBANCE CAUSING SOME -SN IN THE NRN
PLAINS.
TODAY...AS THE UPR JET CORE SHIFTS TO THE E TODAY...EXPECT
THICKENING HI/MID CLDS UNDER ACCOMPANYING UPR DVGC IN THE RRQ OF
THIS FEATURE AS SFC HI PRES RDG HANGS BACK INTO THE UPR LKS. AS THE
FLOW BACKS TO THE SW...ANY LK CLDS OVER THE E SHOULD SHIFT BACK INTO
THE LK. MOST OF THE LARGER SCALE MODELS SHOW SOME PCPN ARRIVING NEAR
THE WI BORDER AFT 18Z AS BAND OF H7-75 FGEN SHIFTS TO THE NE.
HOWEVER...MOST OF THE HIER RES MODELS SHOW ONLY PATCHY QPF. BIGGEST
IMPEDIMENT WL BE LINGERING LLVL DRY AIR AND ABSENCE OF ANY SGNFT
UPSLOPE WIND COMPONENT THAT IS AIDING THE LLVL MOISTENING UPSTREAM.
OTHER NEGATIVES INCLUDE QUICK DEPARTURE OF UPR JET CORE TO THE E AFT
18Z AND WEAKENING MID LVL ISENTROPIC ASCENT. SO OPTED TO CUT BACK ON
POPS OVER THE N HALF OF THE CWA...WITH HIER POPS FOR SOME -SN/-RA
NEAR THE WI BORDER...ESPECIALLY IN MNM COUNTY/SCENTRAL WITH A LGT
UPSLOPE SE WIND JUST TO THE S OF SFC RDG AXIS. THICKENING CLDS
SHOULD RESTRICT THE DIURNAL TEMP RECOVERY...SO TENDED TOWARD THE
LOWER END OF GUIDANCE FOR MAX TEMPS.
TONIGHT...SUPPORT FOR PCPN IN THE EVNG WL FADE WITH THE ARRIVAL OF
LARGER SCALE QVECTOR DVGC/UPR CNVGC IN ADVANCE OF THE UPR RDG MOVING
NEWD FM THE PLAINS. ENDED THIS LINGERING PCPN OVER MAINLY THE
SCENTRAL BY THE EARLY MRNG HRS ON WED. DESPITE THE VIGOROUS DRYING
ALF...MOST MODEL FCST SDNGS INDICATE MSTR WL LINGER IN THE LOWER
LVLS...ESPECIALLY OVER THE SCENTRAL WHERE PCPN IS MOST LIKELY TO
FALL TODAY. SO MAINTAINED CLDY CONDITIONS IN THIS AREA...WITH
PARTIAL CLRG OVER THE NW. THE LOWEST TEMPS SHOULD OCCUR OVER THE
INTERIOR NW WHERE SOME CLRG IS LIKELY. IF THE CLDS BREAK UP
ELSEWHERE...MIN TEMPS MAY HAVE TO BE ADJUSTED DOWN WITH LGT WINDS
UNDER LINGERING SFC RDG AXIS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 426 AM EDT TUE OCT 29 2013
MID-UPR LEVEL TROUGH SLIDES EAST ACROSS THE NATIONS MID SECTION
WEDNESDAY INTO THURSDAY. INITIAL TROUGHING LIFTS ACROSS GREAT
LAKES TOWARD EASTERN CANADA FRIDAY INTO SATURDAY WHILE SOUTHERN
PORTION OF THE TROUGH DOES NOT EXIT EASTERN CONUS UNTIL LATER IN
THE WEEKEND. AS THE LEADING TROUGH LIFTS TOWARD GREAT LAKES...SFC
LOW PRESSURE TROUGH OVER THE PLAINS ON WEDNESDAY DEVELOPS INTO
1000MB SFC LOW OVER UPR GREAT LAKES BY 12Z THURSDAY...THEN DEEPENS
TO 975-980MB LOW BTWN LK SUPERIOR AND JAMES BAY BY 12Z FRIDAY. AS IT
HAS LOOKED FOR A WHILE...MAIN PERIOD OF PRECIP...IN THE FORM OF
RAIN...OCCURS LATER WEDNESDAY NIGHT INTO THURSDAY WITH MORE
SHOWERY PRECIP TAKING OVER IN WAKE OF THE LOW LATER THURSDAY
NIGHT INTO FRIDAY.
SOUNDINGS FOR WEDNESDAY INDICATE MOISTURE BLO H7 WITH MINIMAL LIFT.
THINKING THE LOW-LEVEL MOISTURE IS OVERDONE...BUT DO EXPECT CLOUDS
TO THICKEN THROUGHOUT THE DAY AS WARM AIR ADVECTION DEVELOPS OUT
AHEAD OF SFC LOW IN THE PLAINS. COULD BE JUST ENOUGH WEAK LIFT AND
MOISTURE ADVECTION TO FORM SOME LGT RAIN LATER IN THE WEST OVER THE
WEST AND SOUTH...NOT A BIG DEAL AT ALL AS PRIMARY AREA OF RAIN WILL
NOT ARRIVE UNTIL LATER WEDNESDAY NIGHT. GIVEN THE CLOUDS...MAX TEMPS
ON WEDNESDAY IN THE LOW-MID 40S. TEMPS SHOULD THEN STAY STEADY OR
SLOWLY RISE THROUGH WEDNESDAY NIGHT.
TIMING OF PRECIP ON WEDNESDAY NIGHT A BIT SLOWER THAN MODELS SHOWED
24 HR AGO. DIVERGENCE ALOFT ON NOSE OF 250MB JET STREAK LIFTING
ACROSS UPR LAKES INTERACTS WITH H85 AND H7 MOISTURE ADVECTION TO THE
NORTH OF SFC-H85 LOWS. EXPECT BRIEF PERIOD OF MODERATE RAIN TO SWEEP
FROM SOUTH TO NORTH ACROSS CWA. EVEN WITH RAIN MOVING THROUGH...PUT
A MENTION OF FOG IN OVERNIGHT WEDNESDAY NIGHT INTO THURSDAY MORNING
AS DWPNTS RISING INTO THE 40S TO LOWER 50S WILL BE RIDING OVER COLDER
GROUND SFC WITH 2 INCH SOIL TEMPS WELL BLO 40 THE LAST WEEK OR SO.
IF THE RAIN EXITS QUICKER...THEN THE FOG WOULD LIKELY BECOME MORE
WIDESPREAD. DRY SLOT/MID-LEVEL DRYING TAPERS OFF RAIN ON THURSDAY
MORNING. AS LONG AS WINDS ARE NOT TOO STRONG FOG COULD PERSIST OVER
THE UPSLOPE AREAS OF CNTRL UPR MICHIGAN INTO THE MIDDLE PART OF THE
DAY. WINDS SHIFT TO WEST AND START TO INCREASE IN THE AFTN AS SFC
LOW CENTER MOVES TO CNTRL OR EASTERN LK SUPERIOR WHILE DEEPENING.
DESPITE CLOUDS/FOG AND SPOTTY RAIN...MAX TEMPS WILL STILL PUSH WELL
INTO THE 50S FROM SHEAR ADVECTION ALONE IN THE WARM SECTOR OF THE
SFC LOW. ANOTHER WAVE OF RAIN COULD DEVELOP LATE AFTN/THURSDAY
EVENING AS PRIMARY HEIGHT FALLS AND DEEP LAYER Q-VECTOR CONVERGENCE
SWEEPS IN OVER MAINLY SOUTH AND EAST CWA. KEPT POPS HIGHEST TO THE
EAST OF MQT AND ESC AS THAT IS WHERE LARGER SCALE FORCING INTERACTS
WITH BETTER MOISTURE ADVECTION. BASED ON GRADIENT OF MID-LEVEL
MOISTURE AND FCST H7-H5 LAPSE RATES...THINKING BETTER CHANCES OF
TSRA WILL REMAIN TO THE SOUTH AND EAST OF CWA LATER THURSDAY AFTN
INTO EVENING.
STRONGER SHORTWAVE/DEEP MOISTURE MAY DROP ACROSS GREAT LAKES FRIDAY
NIGHT INTO SATURDAY WHILE COOLER AIRMASS LINGERS AS H85 TEMPS FALL
TO -4C TO -6C BY 12Z SATURDAY. NW-NNW CYCLONIC FLOW AT 1000-850MB
PERSISTS THROUGH SATURDAY SUGGESTING THERE WILL LIKELY BE SOME LAKE
ENHANCED PRECIP. 1000-850MB/H85-H7 THICKNESSES AND FORECAST SFC
TEMPS POINT TO MAINLY SNOW FOR PTYPE FRIDAY NIGHT INTO SATURDAY
MORNING OVER THE WEST WITH RAIN/SNOW MIX FARTHER EAST. DETAILS WILL
NEED TO BE SORTED OUT LATER THIS WEEK...BUT DOES SEEM THAT THE
FRIDAY NIGHT INTO SATURDAY MORNING PERIOD HOLDS SOME POTENTIAL FOR
ACCUMULATING SNOW OVER THE HIGHER TERRAIN OF WEST AND NORTHWEST UPR
MICHIGAN.
TEMPS COOL FURTHER INTO SATURDAY NIGHT BUT DEEPER MOISTURE AND
CYCLONIC FLOW WILL BE EASING AS SFC-H85 RIDGE NEARS FROM THE WEST.
LAKE EFFECT SNOW SHOWERS COULD CONTINUE MOST OF THE NIGHT...MAINLY
FOR NW FLOW AREAS TO THE EAST OF MARQUETTE. SUNDAY IS A TRANSITION
DAY IN WEATHER. EASTERN CONUS TROUGH EDGES EAST AS STRONGER JET
ENERGY MOVES TO FRONT SIDE OF TROUGH WHICH THEN CLEARS WAY FOR
WESTERN CONUS TROUGH TO EXPAND TOWARD ROCKIES AND RIDGING TO
EXPAND ACROSS THE GREAT LAKES. RIDGING LOOKS BRIEF THOUGH AS THE
TROUGHING OVER THE WESTERN CONUS EXPANDS INTO THE PLAINS LEADING
TO A POTENTIALLY ACTIVE SW FLOW PATTERN ACROSS THE GREAT LAKES BY
EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 118 PM EDT TUE OCT 29 2013
EXPECT VFR CONDITIONS AND LGT WINDS UNDER LINGERING SFC RDG AXIS
THRU MID AFTERNOON. AN UPR DISTURBANCE WL BRING SOME -SN TO
MAINLY THE S HALF OF UPR MI LATE THIS AFTN/EVNG...AND CONDITIONS
WILL DROP TO MVFR AT THE MORE SRN SAW/IWD LOCATIONS DURING THIS TIME
WHEN THE LLVL DRY AIR IS MOISTENED SUFFICIENTLY BY THE PCPN. CMX IS
LIKELY TO REMAIN VFR WITH THE PCPN REMAINING TO THE S.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 426 AM EDT TUE OCT 29 2013
LIGHT WINDS LESS THAN 20 KTS THROUGH WEDNESDAY AS HIGH PRESSURE
RIDGE OVER THE AREA SLOWLY MOVES TOWARD THE EAST COAST. LOW PRESSURE
DEVELOPING OVER THE PLAINS ON WEDNESDAY WILL LIFT TOWARD THE UPPER
GREAT LAKES ON THURSDAY THEN DEEPEN AS IT MOVES INTO QUEBEC ON
FRIDAY. SE-E WINDS 20-25 KTS WEDNESDAY NIGHT INTO THURSDAY AHEAD OF
THE SYSTEM...THEN AFTER THE LOW MOVES EAST OF THE LAKE...EXPECT
WINDS TO SHIFT NW 25-30 KTS THURSDAY NIGHT THROUGH SATURDAY AS
COLDER AIR PLUNGES ACROSS THE UPPER LAKES REGION. WINDS DIMINISH
ON SUNDAY WITH ARRIVAL OF HIGH PRESSURE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...07
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
725 AM EDT TUE OCT 29 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 426 AM EDT TUE OCT 29 2013
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A NW FLOW ALF OVER
THE UPR GREAT LKS BTWN UPR TROF CENTERED OVER ERN HUDSON BAY AND A
RDG IN THE PLAINS. SPRAWLING SFC HI PRES/DRY AIRMASS WITH PWAT AOB
0.25 INCH IS CENTERED OVER THE UPR LKS...BRINGING QUIET WX TO THE
CWA. ALTHOUGH SOME HI CLDS IN THE RRQ OF A 100KT H3 JET MAX ARE
STREAMING INTO THE CWA...TEMPS HAVE FALLEN SHARPLY AND INTO THE
TEENS OVER INTERIOR LOCATIONS WITH LIGHT WINDS UNDER THE SFC HI.
MORE SC DOES LINGER OVER THE E NEAR LK SUP WITH LLVL NW FLOW E OF
THE HI CENTER...AND THESE CLDS HAVE RESTRICTED THE DIURNAL TEMP FALL
IN THIS AREA. LOOKING TO THE W...DESPITE SOME DRY LLVL AIR SHOWN ON
THE 00Z ABERDEEN SDAKOTA AND BISMARK RAOBS...THERE IS AN AREA OF -SN
OVER SRN NDAKOTA AND NRN SDAKOTA. THE PRIMARY FORCING MECHANISMS
APPEAR TO BE SOME ISENTROPIC ASCENT ON THE 295-300K SFCS AS WELL AS
A BAND OF H7-75 FGEN UNDER UPR DVGC IN RRQ OF THE H3 JET MAX. AN
UPSLOPE SFC E WIND ALSO APPEARS TO BE AIDING IN THE LLVL MOISTENING
DESPITE THE LLVL DRY AIR FEED OUT OF THE E ON THE SRN FLANK OF THE
SFC HI PRES RDG.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE PCPN CHCS OVER UPR MI
RELATED TO THE UPSTREAM DISTURBANCE CAUSING SOME -SN IN THE NRN
PLAINS.
TODAY...AS THE UPR JET CORE SHIFTS TO THE E TODAY...EXPECT
THICKENING HI/MID CLDS UNDER ACCOMPANYING UPR DVGC IN THE RRQ OF
THIS FEATURE AS SFC HI PRES RDG HANGS BACK INTO THE UPR LKS. AS THE
FLOW BACKS TO THE SW...ANY LK CLDS OVER THE E SHOULD SHIFT BACK INTO
THE LK. MOST OF THE LARGER SCALE MODELS SHOW SOME PCPN ARRIVING NEAR
THE WI BORDER AFT 18Z AS BAND OF H7-75 FGEN SHIFTS TO THE NE.
HOWEVER...MOST OF THE HIER RES MODELS SHOW ONLY PATCHY QPF. BIGGEST
IMPEDIMENT WL BE LINGERING LLVL DRY AIR AND ABSENCE OF ANY SGNFT
UPSLOPE WIND COMPONENT THAT IS AIDING THE LLVL MOISTENING UPSTREAM.
OTHER NEGATIVES INCLUDE QUICK DEPARTURE OF UPR JET CORE TO THE E AFT
18Z AND WEAKENING MID LVL ISENTROPIC ASCENT. SO OPTED TO CUT BACK ON
POPS OVER THE N HALF OF THE CWA...WITH HIER POPS FOR SOME -SN/-RA
NEAR THE WI BORDER...ESPECIALLY IN MNM COUNTY/SCENTRAL WITH A LGT
UPSLOPE SE WIND JUST TO THE S OF SFC RDG AXIS. THICKENING CLDS
SHOULD RESTRICT THE DIURNAL TEMP RECOVERY...SO TENDED TOWARD THE
LOWER END OF GUIDANCE FOR MAX TEMPS.
TONIGHT...SUPPORT FOR PCPN IN THE EVNG WL FADE WITH THE ARRIVAL OF
LARGER SCALE QVECTOR DVGC/UPR CNVGC IN ADVANCE OF THE UPR RDG MOVING
NEWD FM THE PLAINS. ENDED THIS LINGERING PCPN OVER MAINLY THE
SCENTRAL BY THE EARLY MRNG HRS ON WED. DESPITE THE VIGOROUS DRYING
ALF...MOST MODEL FCST SDNGS INDICATE MSTR WL LINGER IN THE LOWER
LVLS...ESPECIALLY OVER THE SCENTRAL WHERE PCPN IS MOST LIKELY TO
FALL TODAY. SO MAINTAINED CLDY CONDITIONS IN THIS AREA...WITH
PARTIAL CLRG OVER THE NW. THE LOWEST TEMPS SHOULD OCCUR OVER THE
INTERIOR NW WHERE SOME CLRG IS LIKELY. IF THE CLDS BREAK UP
ELSEWHERE...MIN TEMPS MAY HAVE TO BE ADJUSTED DOWN WITH LGT WINDS
UNDER LINGERING SFC RDG AXIS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 426 AM EDT TUE OCT 29 2013
MID-UPR LEVEL TROUGH SLIDES EAST ACROSS THE NATIONS MID SECTION
WEDNESDAY INTO THURSDAY. INITIAL TROUGHING LIFTS ACROSS GREAT
LAKES TOWARD EASTERN CANADA FRIDAY INTO SATURDAY WHILE SOUTHERN
PORTION OF THE TROUGH DOES NOT EXIT EASTERN CONUS UNTIL LATER IN
THE WEEKEND. AS THE LEADING TROUGH LIFTS TOWARD GREAT LAKES...SFC
LOW PRESSURE TROUGH OVER THE PLAINS ON WEDNESDAY DEVELOPS INTO
1000MB SFC LOW OVER UPR GREAT LAKES BY 12Z THURSDAY...THEN DEEPENS
TO 975-980MB LOW BTWN LK SUPERIOR AND JAMES BAY BY 12Z FRIDAY. AS IT
HAS LOOKED FOR A WHILE...MAIN PERIOD OF PRECIP...IN THE FORM OF
RAIN...OCCURS LATER WEDNESDAY NIGHT INTO THURSDAY WITH MORE
SHOWERY PRECIP TAKING OVER IN WAKE OF THE LOW LATER THURSDAY
NIGHT INTO FRIDAY.
SOUNDINGS FOR WEDNESDAY INDICATE MOISTURE BLO H7 WITH MINIMAL LIFT.
THINKING THE LOW-LEVEL MOISTURE IS OVERDONE...BUT DO EXPECT CLOUDS
TO THICKEN THROUGHOUT THE DAY AS WARM AIR ADVECTION DEVELOPS OUT
AHEAD OF SFC LOW IN THE PLAINS. COULD BE JUST ENOUGH WEAK LIFT AND
MOISTURE ADVECTION TO FORM SOME LGT RAIN LATER IN THE WEST OVER THE
WEST AND SOUTH...NOT A BIG DEAL AT ALL AS PRIMARY AREA OF RAIN WILL
NOT ARRIVE UNTIL LATER WEDNESDAY NIGHT. GIVEN THE CLOUDS...MAX TEMPS
ON WEDNESDAY IN THE LOW-MID 40S. TEMPS SHOULD THEN STAY STEADY OR
SLOWLY RISE THROUGH WEDNESDAY NIGHT.
TIMING OF PRECIP ON WEDNESDAY NIGHT A BIT SLOWER THAN MODELS SHOWED
24 HR AGO. DIVERGENCE ALOFT ON NOSE OF 250MB JET STREAK LIFTING
ACROSS UPR LAKES INTERACTS WITH H85 AND H7 MOISTURE ADVECTION TO THE
NORTH OF SFC-H85 LOWS. EXPECT BRIEF PERIOD OF MODERATE RAIN TO SWEEP
FROM SOUTH TO NORTH ACROSS CWA. EVEN WITH RAIN MOVING THROUGH...PUT
A MENTION OF FOG IN OVERNIGHT WEDNESDAY NIGHT INTO THURSDAY MORNING
AS DWPNTS RISING INTO THE 40S TO LOWER 50S WILL BE RIDING OVER COLDER
GROUND SFC WITH 2 INCH SOIL TEMPS WELL BLO 40 THE LAST WEEK OR SO.
IF THE RAIN EXITS QUICKER...THEN THE FOG WOULD LIKELY BECOME MORE
WIDESPREAD. DRY SLOT/MID-LEVEL DRYING TAPERS OFF RAIN ON THURSDAY
MORNING. AS LONG AS WINDS ARE NOT TOO STRONG FOG COULD PERSIST OVER
THE UPSLOPE AREAS OF CNTRL UPR MICHIGAN INTO THE MIDDLE PART OF THE
DAY. WINDS SHIFT TO WEST AND START TO INCREASE IN THE AFTN AS SFC
LOW CENTER MOVES TO CNTRL OR EASTERN LK SUPERIOR WHILE DEEPENING.
DESPITE CLOUDS/FOG AND SPOTTY RAIN...MAX TEMPS WILL STILL PUSH WELL
INTO THE 50S FROM SHEAR ADVECTION ALONE IN THE WARM SECTOR OF THE
SFC LOW. ANOTHER WAVE OF RAIN COULD DEVELOP LATE AFTN/THURSDAY
EVENING AS PRIMARY HEIGHT FALLS AND DEEP LAYER Q-VECTOR CONVERGENCE
SWEEPS IN OVER MAINLY SOUTH AND EAST CWA. KEPT POPS HIGHEST TO THE
EAST OF MQT AND ESC AS THAT IS WHERE LARGER SCALE FORCING INTERACTS
WITH BETTER MOISTURE ADVECTION. BASED ON GRADIENT OF MID-LEVEL
MOISTURE AND FCST H7-H5 LAPSE RATES...THINKING BETTER CHANCES OF
TSRA WILL REMAIN TO THE SOUTH AND EAST OF CWA LATER THURSDAY AFTN
INTO EVENING.
STRONGER SHORTWAVE/DEEP MOISTURE MAY DROP ACROSS GREAT LAKES FRIDAY
NIGHT INTO SATURDAY WHILE COOLER AIRMASS LINGERS AS H85 TEMPS FALL
TO -4C TO -6C BY 12Z SATURDAY. NW-NNW CYCLONIC FLOW AT 1000-850MB
PERSISTS THROUGH SATURDAY SUGGESTING THERE WILL LIKELY BE SOME LAKE
ENHANCED PRECIP. 1000-850MB/H85-H7 THICKNESSES AND FORECAST SFC
TEMPS POINT TO MAINLY SNOW FOR PTYPE FRIDAY NIGHT INTO SATURDAY
MORNING OVER THE WEST WITH RAIN/SNOW MIX FARTHER EAST. DETAILS WILL
NEED TO BE SORTED OUT LATER THIS WEEK...BUT DOES SEEM THAT THE
FRIDAY NIGHT INTO SATURDAY MORNING PERIOD HOLDS SOME POTENTIAL FOR
ACCUMULATING SNOW OVER THE HIGHER TERRAIN OF WEST AND NORTHWEST UPR
MICHIGAN.
TEMPS COOL FURTHER INTO SATURDAY NIGHT BUT DEEPER MOISTURE AND
CYCLONIC FLOW WILL BE EASING AS SFC-H85 RIDGE NEARS FROM THE WEST.
LAKE EFFECT SNOW SHOWERS COULD CONTINUE MOST OF THE NIGHT...MAINLY
FOR NW FLOW AREAS TO THE EAST OF MARQUETTE. SUNDAY IS A TRANSITION
DAY IN WEATHER. EASTERN CONUS TROUGH EDGES EAST AS STRONGER JET
ENERGY MOVES TO FRONT SIDE OF TROUGH WHICH THEN CLEARS WAY FOR
WESTERN CONUS TROUGH TO EXPAND TOWARD ROCKIES AND RIDGING TO
EXPAND ACROSS THE GREAT LAKES. RIDGING LOOKS BRIEF THOUGH AS THE
TROUGHING OVER THE WESTERN CONUS EXPANDS INTO THE PLAINS LEADING
TO A POTENTIALLY ACTIVE SW FLOW PATTERN ACROSS THE GREAT LAKES BY
EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 724 AM EDT TUE OCT 29 2013
ALTHOUGH THERE WL BE A TREND TOWARD THICKENING HI/MID CLDS WELL N OF
A WARM FNT...EXPECT VFR CONDITIONS AND LGT WINDS UNDER LINGERING SFC
RDG AXIS THRU AT LEAST MOST OF TODAY. AN UPR DISTURBANCE WL BRING
SOME -SN TO MAINLY THE S HALF OF UPR MI LATE THIS AFTN/EVNG...AND
CONDITIONS MAY DROP TO MVFR AT THE MORE SRN SAW/IWD LOCATIONS DURING
THIS TIME IF THE LLVL DRY AIR IS MOISTENED SUFFICIENTLY. CMX IS
LIKELY TO REMAIN VFR WITH THE PCPN REMAINING TO THE S.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 426 AM EDT TUE OCT 29 2013
LIGHT WINDS LESS THAN 20 KTS THROUGH WEDNESDAY AS HIGH PRESSURE
RIDGE OVER THE AREA SLOWLY MOVES TOWARD THE EAST COAST. LOW PRESSURE
DEVELOPING OVER THE PLAINS ON WEDNESDAY WILL LIFT TOWARD THE UPPER
GREAT LAKES ON THURSDAY THEN DEEPEN AS IT MOVES INTO QUEBEC ON
FRIDAY. SE-E WINDS 20-25 KTS WEDNESDAY NIGHT INTO THURSDAY AHEAD OF
THE SYSTEM...THEN AFTER THE LOW MOVES EAST OF THE LAKE...EXPECT
WINDS TO SHIFT NW 25-30 KTS THURSDAY NIGHT THROUGH SATURDAY AS
COLDER AIR PLUNGES ACROSS THE UPPER LAKES REGION. WINDS DIMINISH
ON SUNDAY WITH ARRIVAL OF HIGH PRESSURE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...KC
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
428 AM EDT TUE OCT 29 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 426 AM EDT TUE OCT 29 2013
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A NW FLOW ALF OVER
THE UPR GREAT LKS BTWN UPR TROF CENTERED OVER ERN HUDSON BAY AND A
RDG IN THE PLAINS. SPRAWLING SFC HI PRES/DRY AIRMASS WITH PWAT AOB
0.25 INCH IS CENTERED OVER THE UPR LKS...BRINGING QUIET WX TO THE
CWA. ALTHOUGH SOME HI CLDS IN THE RRQ OF A 100KT H3 JET MAX ARE
STREAMING INTO THE CWA...TEMPS HAVE FALLEN SHARPLY AND INTO THE
TEENS OVER INTERIOR LOCATIONS WITH LIGHT WINDS UNDER THE SFC HI.
MORE SC DOES LINGER OVER THE E NEAR LK SUP WITH LLVL NW FLOW E OF
THE HI CENTER...AND THESE CLDS HAVE RESTRICTED THE DIURNAL TEMP FALL
IN THIS AREA. LOOKING TO THE W...DESPITE SOME DRY LLVL AIR SHOWN ON
THE 00Z ABERDEEN SDAKOTA AND BISMARK RAOBS...THERE IS AN AREA OF -SN
OVER SRN NDAKOTA AND NRN SDAKOTA. THE PRIMARY FORCING MECHANISMS
APPEAR TO BE SOME ISENTROPIC ASCENT ON THE 295-300K SFCS AS WELL AS
A BAND OF H7-75 FGEN UNDER UPR DVGC IN RRQ OF THE H3 JET MAX. AN
UPSLOPE SFC E WIND ALSO APPEARS TO BE AIDING IN THE LLVL MOISTENING
DESPITE THE LLVL DRY AIR FEED OUT OF THE E ON THE SRN FLANK OF THE
SFC HI PRES RDG.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE PCPN CHCS OVER UPR MI
RELATED TO THE UPSTREAM DISTURBANCE CAUSING SOME -SN IN THE NRN
PLAINS.
TODAY...AS THE UPR JET CORE SHIFTS TO THE E TODAY...EXPECT
THICKENING HI/MID CLDS UNDER ACCOMPANYING UPR DVGC IN THE RRQ OF
THIS FEATURE AS SFC HI PRES RDG HANGS BACK INTO THE UPR LKS. AS THE
FLOW BACKS TO THE SW...ANY LK CLDS OVER THE E SHOULD SHIFT BACK INTO
THE LK. MOST OF THE LARGER SCALE MODELS SHOW SOME PCPN ARRIVING NEAR
THE WI BORDER AFT 18Z AS BAND OF H7-75 FGEN SHIFTS TO THE NE.
HOWEVER...MOST OF THE HIER RES MODELS SHOW ONLY PATCHY QPF. BIGGEST
IMPEDIMENT WL BE LINGERING LLVL DRY AIR AND ABSENCE OF ANY SGNFT
UPSLOPE WIND COMPONENT THAT IS AIDING THE LLVL MOISTENING UPSTREAM.
OTHER NEGATIVES INCLUDE QUICK DEPARTURE OF UPR JET CORE TO THE E AFT
18Z AND WEAKENING MID LVL ISENTROPIC ASCENT. SO OPTED TO CUT BACK ON
POPS OVER THE N HALF OF THE CWA...WITH HIER POPS FOR SOME -SN/-RA
NEAR THE WI BORDER...ESPECIALLY IN MNM COUNTY/SCENTRAL WITH A LGT
UPSLOPE SE WIND JUST TO THE S OF SFC RDG AXIS. THICKENING CLDS
SHOULD RESTRICT THE DIURNAL TEMP RECOVERY...SO TENDED TOWARD THE
LOWER END OF GUIDANCE FOR MAX TEMPS.
TONIGHT...SUPPORT FOR PCPN IN THE EVNG WL FADE WITH THE ARRIVAL OF
LARGER SCALE QVECTOR DVGC/UPR CNVGC IN ADVANCE OF THE UPR RDG MOVING
NEWD FM THE PLAINS. ENDED THIS LINGERING PCPN OVER MAINLY THE
SCENTRAL BY THE EARLY MRNG HRS ON WED. DESPITE THE VIGOROUS DRYING
ALF...MOST MODEL FCST SDNGS INDICATE MSTR WL LINGER IN THE LOWER
LVLS...ESPECIALLY OVER THE SCENTRAL WHERE PCPN IS MOST LIKELY TO
FALL TODAY. SO MAINTAINED CLDY CONDITIONS IN THIS AREA...WITH
PARTIAL CLRG OVER THE NW. THE LOWEST TEMPS SHOULD OCCUR OVER THE
INTERIOR NW WHERE SOME CLRG IS LIKELY. IF THE CLDS BREAK UP
ELSEWHERE...MIN TEMPS MAY HAVE TO BE ADJUSTED DOWN WITH LGT WINDS
UNDER LINGERING SFC RDG AXIS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 426 AM EDT TUE OCT 29 2013
MID-UPR LEVEL TROUGH SLIDES EAST ACROSS THE NATIONS MID SECTION
WEDNESDAY INTO THURSDAY. INITIAL TROUGHING LIFTS ACROSS GREAT
LAKES TOWARD EASTERN CANADA FRIDAY INTO SATURDAY WHILE SOUTHERN
PORTION OF THE TROUGH DOES NOT EXIT EASTERN CONUS UNTIL LATER IN
THE WEEKEND. AS THE LEADING TROUGH LIFTS TOWARD GREAT LAKES...SFC
LOW PRESSURE TROUGH OVER THE PLAINS ON WEDNESDAY DEVELOPS INTO
1000MB SFC LOW OVER UPR GREAT LAKES BY 12Z THURSDAY...THEN DEEPENS
TO 975-980MB LOW BTWN LK SUPERIOR AND JAMES BAY BY 12Z FRIDAY. AS IT
HAS LOOKED FOR A WHILE...MAIN PERIOD OF PRECIP...IN THE FORM OF
RAIN...OCCURS LATER WEDNESDAY NIGHT INTO THURSDAY WITH MORE
SHOWERY PRECIP TAKING OVER IN WAKE OF THE LOW LATER THURSDAY
NIGHT INTO FRIDAY.
SOUNDINGS FOR WEDNESDAY INDICATE MOISTURE BLO H7 WITH MINIMAL LIFT.
THINKING THE LOW-LEVEL MOISTURE IS OVERDONE...BUT DO EXPECT CLOUDS
TO THICKEN THROUGHOUT THE DAY AS WARM AIR ADVECTION DEVELOPS OUT
AHEAD OF SFC LOW IN THE PLAINS. COULD BE JUST ENOUGH WEAK LIFT AND
MOISTURE ADVECTION TO FORM SOME LGT RAIN LATER IN THE WEST OVER THE
WEST AND SOUTH...NOT A BIG DEAL AT ALL AS PRIMARY AREA OF RAIN WILL
NOT ARRIVE UNTIL LATER WEDNESDAY NIGHT. GIVEN THE CLOUDS...MAX TEMPS
ON WEDNESDAY IN THE LOW-MID 40S. TEMPS SHOULD THEN STAY STEADY OR
SLOWLY RISE THROUGH WEDNESDAY NIGHT.
TIMING OF PRECIP ON WEDNESDAY NIGHT A BIT SLOWER THAN MODELS SHOWED
24 HR AGO. DIVERGENCE ALOFT ON NOSE OF 250MB JET STREAK LIFTING
ACROSS UPR LAKES INTERACTS WITH H85 AND H7 MOISTURE ADVECTION TO THE
NORTH OF SFC-H85 LOWS. EXPECT BRIEF PERIOD OF MODERATE RAIN TO SWEEP
FROM SOUTH TO NORTH ACROSS CWA. EVEN WITH RAIN MOVING THROUGH...PUT
A MENTION OF FOG IN OVERNIGHT WEDNESDAY NIGHT INTO THURSDAY MORNING
AS DWPNTS RISING INTO THE 40S TO LOWER 50S WILL BE RIDING OVER COLDER
GROUND SFC WITH 2 INCH SOIL TEMPS WELL BLO 40 THE LAST WEEK OR SO.
IF THE RAIN EXITS QUICKER...THEN THE FOG WOULD LIKELY BECOME MORE
WIDESPREAD. DRY SLOT/MID-LEVEL DRYING TAPERS OFF RAIN ON THURSDAY
MORNING. AS LONG AS WINDS ARE NOT TOO STRONG FOG COULD PERSIST OVER
THE UPSLOPE AREAS OF CNTRL UPR MICHIGAN INTO THE MIDDLE PART OF THE
DAY. WINDS SHIFT TO WEST AND START TO INCREASE IN THE AFTN AS SFC
LOW CENTER MOVES TO CNTRL OR EASTERN LK SUPERIOR WHILE DEEPENING.
DESPITE CLOUDS/FOG AND SPOTTY RAIN...MAX TEMPS WILL STILL PUSH WELL
INTO THE 50S FROM SHEAR ADVECTION ALONE IN THE WARM SECTOR OF THE
SFC LOW. ANOTHER WAVE OF RAIN COULD DEVELOP LATE AFTN/THURSDAY
EVENING AS PRIMARY HEIGHT FALLS AND DEEP LAYER Q-VECTOR CONVERGENCE
SWEEPS IN OVER MAINLY SOUTH AND EAST CWA. KEPT POPS HIGHEST TO THE
EAST OF MQT AND ESC AS THAT IS WHERE LARGER SCALE FORCING INTERACTS
WITH BETTER MOISTURE ADVECTION. BASED ON GRADIENT OF MID-LEVEL
MOISTURE AND FCST H7-H5 LAPSE RATES...THINKING BETTER CHANCES OF
TSRA WILL REMAIN TO THE SOUTH AND EAST OF CWA LATER THURSDAY AFTN
INTO EVENING.
STRONGER SHORTWAVE/DEEP MOISTURE MAY DROP ACROSS GREAT LAKES FRIDAY
NIGHT INTO SATURDAY WHILE COOLER AIRMASS LINGERS AS H85 TEMPS FALL
TO -4C TO -6C BY 12Z SATURDAY. NW-NNW CYCLONIC FLOW AT 1000-850MB
PERSISTS THROUGH SATURDAY SUGGESTING THERE WILL LIKELY BE SOME LAKE
ENHANCED PRECIP. 1000-850MB/H85-H7 THICKNESSES AND FORECAST SFC
TEMPS POINT TO MAINLY SNOW FOR PTYPE FRIDAY NIGHT INTO SATURDAY
MORNING OVER THE WEST WITH RAIN/SNOW MIX FARTHER EAST. DETAILS WILL
NEED TO BE SORTED OUT LATER THIS WEEK...BUT DOES SEEM THAT THE
FRIDAY NIGHT INTO SATURDAY MORNING PERIOD HOLDS SOME POTENTIAL FOR
ACCUMULATING SNOW OVER THE HIGHER TERRAIN OF WEST AND NORTHWEST UPR
MICHIGAN.
TEMPS COOL FURTHER INTO SATURDAY NIGHT BUT DEEPER MOISTURE AND
CYCLONIC FLOW WILL BE EASING AS SFC-H85 RIDGE NEARS FROM THE WEST.
LAKE EFFECT SNOW SHOWERS COULD CONTINUE MOST OF THE NIGHT...MAINLY
FOR NW FLOW AREAS TO THE EAST OF MARQUETTE. SUNDAY IS A TRANSITION
DAY IN WEATHER. EASTERN CONUS TROUGH EDGES EAST AS STRONGER JET
ENERGY MOVES TO FRONT SIDE OF TROUGH WHICH THEN CLEARS WAY FOR
WESTERN CONUS TROUGH TO EXPAND TOWARD ROCKIES AND RIDGING TO
EXPAND ACROSS THE GREAT LAKES. RIDGING LOOKS BRIEF THOUGH AS THE
TROUGHING OVER THE WESTERN CONUS EXPANDS INTO THE PLAINS LEADING
TO A POTENTIALLY ACTIVE SW FLOW PATTERN ACROSS THE GREAT LAKES BY
EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 125 AM EDT TUE OCT 29 2013
ALTHOUGH THERE WL BE A TREND TOWARD THICKENING HI/MID CLDS WELL N OF
A WARM FNT...EXPECT VFR CONDITIONS AND LGT WINDS UNDER LINGERING SFC
RDG AXIS THRU AT LEAST MOST OF THE DAY. AN UPR DISTURBANCE WL BRING
SOME -SN TO MAINLY THE S HALF OF UPR MI LATE THIS AFTN/EVNG...AND
CONDITIONS MAY DROP TO MVFR AT THE MORE SRN SAW/IWD LOCATIONS DURING
THIS TIME IF THE LLVL DRY AIR IS MOISTENED SUFFICIENTLY.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 426 AM EDT TUE OCT 29 2013
LIGHT WINDS LESS THAN 20 KTS THROUGH WEDNESDAY AS HIGH PRESSURE
RIDGE OVER THE AREA SLOWLY MOVES TOWARD THE EAST COAST. LOW PRESSURE
DEVELOPING OVER THE PLAINS ON WEDNESDAY WILL LIFT TOWARD THE UPPER
GREAT LAKES ON THURSDAY THEN DEEPEN AS IT MOVES INTO QUEBEC ON
FRIDAY. SE-E WINDS 20-25 KTS WEDNESDAY NIGHT INTO THURSDAY AHEAD OF
THE SYSTEM...THEN AFTER THE LOW MOVES EAST OF THE LAKE...EXPECT
WINDS TO SHIFT NW 25-30 KTS THURSDAY NIGHT THROUGH SATURDAY AS
COLDER AIR PLUNGES ACROSS THE UPPER LAKES REGION. WINDS DIMINISH
ON SUNDAY WITH ARRIVAL OF HIGH PRESSURE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...KC
MARINE...JLA
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
730 PM CDT WED OCT 30 2013
.UPDATE...
ISSUED AT 649 PM CDT WED OCT 30 2013
UPDATED GRIDDED AND TEXT PRODUCTS TO INCLUDE ISSUANCE OF A DENSE
FOG ADVY FOR THIS EVENING THROUGH LATE THU MORNING. OBS OF 1/2SM
OR LESS...WITH MANY 1/4SM OR LESS...HAVE BECOME COMMON IN MUCH OF
CENTRAL-SRN MN THIS EVE AND THIS IS EXPECTED TO SPREAD INTO
W-CENTRAL WI BY MIDNIGHT OR SO. LIGHT WINDS COMBINED WITH PLENTY
OF LOW LEVEL MOISTURE WITHIN THE BLYR HAVE CONTRIBUTED TO THE
DEVELOPMENT OF FOG OVER NEARLY THE ENTIRE COVERAGE AREA.
HRRR/SREF/HOPWRF ALL INDICATE THE DEGRADED VSBY TO REMAIN IN PLACE
FOR MUCH OF THE OVERNIGHT SO HAVE OPTED TO HOIST A DENSE FOG ADVY
SINCE THERE IS VIRTUALLY NO INDICATION OF THE FOG LIFTING ANYTIME
SOON.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 400 PM CDT WED OCT 30 2013
DREARY FALL WEATHER WILL CONTINUE TONIGHT AND EARLY THURSDAY
MORNING UNTIL A SURFACE LOW AND COLD FRONT SLIDE EAST OF THE
FORECAST AREA. SEVERAL AREAS OF DRIZZLE AND WIDESPREAD FOG HAVE
PERSISTED FOR MOST OF THE DAY. MSLP HAS FALLEN 5-7 MB IN FAR SOUTH
CENTRAL MN IN THE VICINITY OF THE DRY SLOT SHOWING UP ON
SATELLITE. THIS HAS INCREASED THE BL WINDS AND HELPED MIX OUT SOME
OF THE DENSE FOG OBSERVED EARLIER IN THE DAY. HOWEVER...ACROSS
MOST OF CENTRAL MN AND WEST CENTRAL WI...THE FOG HAS ACTUALLY
THICKENED IN MANY LOCATIONS. THESE SAME AREAS WILL HOLD ONTO LIGHT
ENE WINDS THROUGH AT LEAST 06Z /NEAR CALM AT TIMES/. THIS WILL
KEEP THE LOW FOG AND STRATUS IN PLACE. BETWEEN 09-12Z...THE FLOW
WILL INCREASE OUT OF THE W-NW AND ADVECT COOLER/BUT DRIER 925-850
MB AIR INTO MN. THIS SHOULD DO THE TRICK OF BRINGING AN END TO THE
PRECIP. LOCAL WRF SIMULATIONS AND THE PAST COUPLE HRRR RUNS
SUPPORT THIS SCENARIO AS WELL. WE REDUCED POPS/QPF TONIGHT ACROSS
MOST OF THE FORECAST AREA TO ACCOUNT FOR THE SOUTH-EAST TREND IN
THE 12-18Z GUIDANCE. FAR EASTERN PORTIONS OF THE FORECAST AREA
/SUCH AS ALBERT LEA TO EAU CLAIRE/ SHOULD BE RIGHT ALONG OR JUST
NORTH OF THE LOW TRACK AND COULD STILL SEE 0.10-0.25" BETWEEN
03-09Z TONIGHT. OTHERWISE...MUCH MORE THAN TRACE AMOUNTS MIGHT BE
DIFFICULT TO ACCUMULATE ACROSS THE REST OF THE FORECAST AREA. THE
TWIN CITIES METRO COULD STILL PICK UP A FEW HUNDREDTHS TONIGHT.
TOMORROW WILL BE COOL BEHIND THE COLD FRONT WITH LINGERING STRATO
CU...BUT THE WINDS WILL REMAIN ALMOST DUE WESTERLY AND THERE MAY
BE A FEW BREAKS IN THE CLOUDS DURING THE AFTERNOON.
NONETHELESS...MID TO UPPER 40S ARE EXPECTED FOR HIGHS...WHICH IS
JUST A FEW DEGREES BELOW NORMAL.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 400 PM CDT WED OCT 30 2013
NOTHING TOO SCARY WEATHER WISE ACROSS THE REGION THURSDAY EVENING
OTHER THAN A FEW SHOWERS OVER WEST CENTRAL WISCONSIN IN THE WAKE
OF A LOW PRESSURE SYSTEM. A SHORT WAVE AND WEAK LOW PRESSURE
SYSTEM REMAIN ON TRACK TO DROP SOUTHEAST ACROSS THE REGION FRIDAY
AND FRIDAY NIGHT. HIGH CHANCE POPS REMAIN IN PLACE ACROSS THE FA.
WOULD HAVE GONE TO LIKELY AT THIS POINT ACROSS EASTERN MN AND WEST
CENTRAL WI... BASED ON THE NAM AND GFS SOLUTIONS. HOWEVER... THE
GEM AND ECMWF ARE NOT AS ENTHUSIASTIC WITH A MUCH LIGHTER AND
PATCHY PRECIPITATION PATTERN.
HIGH PRESSURE WILL FOLLOW THIS SYSTEM FROM SATURDAY INTO SUNDAY.
SUNDAY LOOKS TO BE THE BEST OF THE TWO DAYS FOR SUNSHINE BUT IT BECOME
QUITE BREEZY/WINDY ACROSS THE FA... ESPECIALLY FROM WEST CENTRAL
INTO SOUTH CENTRAL MN... WHERE SW WINDS NEAR 25 MPH GUSTING TO 35 MPH
ARE LIKELY. THE WIND IS THE RESULT OF A STRENGTHENING PRESSURE
GRADIENT BETWEEN HIGH PRESSURE OVER THE GREAT LAKES AND DEVELOPING
LOW PRESSURE OVER THE WESTERN HIGH PLAINS. THERE COULD BE A PRETTY
GOOD RUN ON THE HIGH TEMPERATURES FOR THE DAY ACROSS SOUTHWEST MN
AS ALONG AS THE DEVELOPING SOUTHERLY LOW LEVEL WAA PATTERN DOES
NOT SLOW MUCH. PUSHED HIGHS UP INTO THE MIDDLE 50S FOR THE SW CWA BASED
ON H85 MIX DOWN FROM THE ECMWF.
AN UNSETTLED WEATHER PATTERN WILL DOMINATE THE REGION FOR MUCH OF
NEXT WEEK AS YET ANOTHER LARGE STORM SYSTEM PUSHES INTO THE
ROCKIES BY MONDAY. THIS SYSTEM FEATURES BOTH NORTHERN AND SOUTHERN
STREAM ENERGY ALOFT. GFS/ECMWF SOLUTIONS HAVE BEEN MEANDERING
AROUND THE PAST FEW DAYS ON HOW THIS SYSTEM MOVES THROUGH OUR
AREA FROM MONDAY NIGHT INTO THURSDAY. THE GFS HAS BEEN TRYING TO
PHASE THE TWO STREAMS OVER THE CENTER OF THE COUNTRY BY WEDNESDAY
WITH SURFACE LOW PRESSURE TRACKING NORTHEAST FROM THE CENTRAL
PLAINS TO THE GREAT LAKES. THE ECMWF HAS KEPT SEPARATION BETWEEN THE
STREAMS. THE ECMWF HAS BECOME QUITE EXTREME TODAY CUTTING OFF AN
UPPER LOW NEAR NORTHERN MEXICO BY MID WEEK. OVERALL... A SLOWER
OUTCOME WILL LIKELY RESULT OVER WHAT THE GFS INDICATES AND PERHAPS
CLOSER TO THE ECMWF. HENCE... A RATHER WET PERIOD IS LIKELY NEXT
WEEK. THE THREAT FOR SNOW IS MINIMAL AS LONG AS THE NORTHERN AND
SOUTHERN STREAMS KEEP THEIR DISTANCE LIKE THE ECMWF INDICATES.
MORE PHASING LIKE THE GFS WOULD PREFER COULD LEAD TO TROUBLE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 649 PM CDT WED OCT 30 2013
WIDESPREAD IFR-AND-WORSE CONDITIONS THROUGH THE OVERNIGHT HOURS.
TAF SITES IN MN HAVE DROPPED TO 1/2SM OR LESS VSBY WITH OVC003 OR
LOWER CEILINGS. WI TAF SITES WILL FOLLOW SUIT BY 04Z-06Z. DEGRADED
CONDITIONS WILL LAST THROUGH DAYBREAK THU MRNG AND LIKELY TO
AROUND MIDDAY BEFORE APPRECIABLE IMPROVEMENT OCCURS. IFR-MVFR
CEILINGS WILL LIKELY PERSIST THROUGH TMRW AFTN WHILE VSBYS IMPROVE
QUICKER. WINDS WILL SHIFT TO W AT ARND 10 KT AFTER REMAINING
LGT/VRBL OVERNIGHT.
KMSP...IFR-OR-LOWER CONDITIONS...ESPECIALLY LIFR AND VLIFR...WILL
PREVAIL OVERNIGHT DUE TO FOG. VSBY WILL COMMONLY BE 1/4SM OR LESS
THROUGH DAYBREAK WITH CEILINGS IN THE 100-200 FT RANGE. CONDS WILL
SLOWLY IMPROVE DURING THE DAY TMRW...BUT IFR-OR-WORSE CONDITIONS
WILL LIKELY LAST THRU DAYBREAK AND INTO MIDDAY. THIS INCLUDES VSBY
3SM OR LESS AND CEILINGS WELL BELOW 1700 FT. CONDITIONS IMPROVE TO
MVFR LATE TMRW AFTN AND CONTINUE IMPROVING TO VFR BY TMRW EVE.
/OUTLOOK FOR KMSP/
FRI...MVFR CIGS POSSIBLE WITH CHC -SHRA. WINDS W 15G25 KT.
SAT...VFR. WINDS NW 10-15 KT.
SUN...VFR. WINDS SE 10-20 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...DENSE FOG ADVISORY UNTIL 10 AM CDT THURSDAY FOR MNZ041>045-
047>070-073>078-082>085-091>093.
WI...DENSE FOG ADVISORY UNTIL 10 AM CDT THURSDAY FOR WIZ014>016-
023>028.
&&
$$
UPDATE...JPC
SHORT TERM...CLF
LONG TERM...RAH
AVIATION...JPC
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
346 AM CDT TUE OCT 29 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT TUE OCT 29 2013
LIGHT PRECIP WILL OVERSPREAD THE AREA THIS MORNING. WHILE THE CHANCE
OF RECEIVING MEASURABLE PRECIP IS HIGH...PRECIP AMOUNTS WILL BE LOW
/LIQUID AMOUNTS UNDER ONE TENTH OF AN INCH AND SNOW ACCUMS ONE HALF
INCH OR LESS/. RAIN AND SNOW WILL REMAIN POSSIBLE ACROSS THE FORECAST
AREA THROUGH THIS MORNING...AND THEN MAINLY NORTH OF INTERSTATE 94
THIS AFTERNOON. THERE WILL REMAIN A THREAT FOR LIGHT FREEZING PRECIP
AND SLEET OVER FAR SOUTHWEST AND WEST CENTRAL MN FOR A FEW HOURS
AFTER DAYBREAK...WHERE BRIGHT BANDING HAS BEEN OBSERVED ON RADAR
OVERNIGHT.
LOW CLOUDS MOVE IN TONIGHT...WITH FAINT ISENTROPIC UPGLIDE
INDICATING THE POTENTIAL FOR OCCASIONAL DRIZZLE OR VERY LIGHT RAIN
/POSSIBLY WITH SOME VERY LIGHT SNOW OVER CENTRAL MN/.
TEMPERATURES WILL REMAIN FAIRLY STATIC OVER THE NEXT 24 HOURS...WITH
HIGHS IN THE UPPER 30S TO UPPER 40S AND LOWS TONIGHT IN THE LOWER
30S TO LOWER 40S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 345 AM CDT TUE OCT 29 2013
MAIN UPPER SYSTEM LIFTS NORTHEAST WEDNESDAY AFTERNOON INTO
THURSDAY. WILL INCREASE POPS FROM SOUTHWEST TO NORTHEAST DURING
THE PERIOD...WITH A PERIOD OF CATEGORICAL POPS INDICATED. LATEST
AVAILABLE SREF PROBABILITY OF THUNDER BRINGS SMALL CHANCE INTO FAR
SOUTHERN MINNESOTA WEDNESDAY AFTERNOON...AND SPREADS IT A BIT
NORTHEAST AND WEAKENS OVERNIGHT. THIS IS IN LINE WITH THE WEAK
MIXED LAYER/MOST UNSTABLE CAPE OF 200-400 J/KG PROGGED OFF THE
GFS AND THE BEST LI`S AS LOW AS MINUS 4. THIS SHOULD BE ENOUGH AT
LEAST FOR AN ISOLATED THUNDER MENTION OVERNIGHT. FAIRLY
SIGNIFICANT MOISTURE TRANSPORT LIFTS NORTH ACROSS SOUTHEAST MN
FROM 00Z.31 THROUGH 06Z.31 AS 35 KT LOW LEVEL JET LIFTS AND IS
SHUNTED TO THE EAST. AS THE UPPER TROUGH LIFTS NORTHEAST...STRONG
HEIGHT FALL CENTER OF OVER 120 DECAMETERS MOVES ACROSS THE AREA
AS 130 KT UPPER JET NOSES INTO THE AREA. 24 HOUR QPF AMOUNTS 12Z
WED THROUGH 12Z THU SHOULD RANGE AROUND ONE HALF TO THREE QUARTERS
OF AN INCH OVER MUCH OF THE CENTRAL AND EASTERN PORTIONS OF THE
CWA.
SOME WRAPAROUND PRECIPITATION POSSIBLE INTO THURSDAY AS THE
SYSTEM EXITS TO THE EAST. SHOULD WANE BY LATE AFTERNOON OVER THE
WEST AND BY EVENING INTO HE EAST. MODELS CONTINUE TO SHOW
POTENTIAL FROM ANOTHER SHORT WAVE DROPPING IN FROM THE NORTHWEST
FOR FRIDAY. WILL HAVE TO MONITOR THIS FOR FURTHER POSSIBILITY OF
ANOTHER LIGHT SHOWERY EVENT MOVING ACROSS THE CWA FRIDAY INTO
FRIDAY NIGHT. ANY PRECIPITATION SHOULD BE LIGHT IF IT DOES OCCUR.
RIDGING ALOFT DEVELOPS THEN INTO THE WEEKEND WITH TEMPERATURES
WARMING BACK THROUGH THE LOWER 50S. SHOULD REMAIN DRY DURING THE
PERIOD AS WELL. THIS MAY LINGER INTO EARLY NEXT WEEK AS WELL...AS
MODELS CONTINUE TO DEVELOP ANOTHER SIGNIFICANT TROUGH OVER THE
WESTERN CONUS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1033 PM CDT MON OCT 28 2013
LOOKING AT THE LAST FEW RUNS OF THE HRRR...ALONG WITH THE 00Z
NAM...IS LOOKING LIKE TONIGHT INTO TUESDAYS PRECIP EVENT MAY TURN
OUT TO BE MUCH ADO ABOUT NOTHING. DID NOT CHANGE INHERITED TAFS
MUCH...OTHER THAN TO REMOVE SNOW MENTION FROM EAU. GIVEN THE WIDE
RANGE OF SOLUTIONS RANGING FROM NOT MUCH HAPPENING /HRRR/ TO A
GOOD AMOUNT OF PRECIP MOVING THROUGH /18Z GFS/...HAVE CONTINUED TO
BE RATHER CONSERVATIVE WITH PRECIP IN TAFS. BASED ON ALL THE DRY
AIR IN THE MPX 00Z SOUNDING...IT MAY BE TOUGH TO GET MUCH OF
ANYTHING TO THE GROUND...SO CONTINUED TO FAVOR THE DRIER END OF
THINGS RIGHT NOW. FOR CIGS...HRRR/RAP WOULD SUGGEST MVFR CIGS IN
TAFS ARE WAY OVER DONE FOR TODAY OUTSIDE OF WRN MN...WITH THE RAP
SHOWING MOST MPX TAFS ENJOYING VFR CONDS TUESDAY. TUESDAY
NIGHT...A MORE SIGNIFICANT PUSH OF MOISTURE WILL BE ARRIVING FROM
THE SOUTH...AND WITH THAT...LOOKS LIKELY THAT ALL TERMINALS WILL
EVENTUALLY END UP WITH IFR OR LOWER CIGS AT SOME POINT TUESDAY
NIGHT.
KMSP...CONFIDENCE BEGINNING TO DECREASE IN MSP SEEING ANY PRECIP
TUE MORNING. STILL LOOKS TO BE A WINDOW FROM ABOUT 12-16Z WHERE A
BRIEF RA OR SN SHOWER COULD BE SEEN...BUT LATEST RUNS OF THE
NAM/HRRR DO NOT LEAVE MUCH HOPE FOR THAT OCCURRING. IN
ADDITION...THE RAP WOULD SAY OTHER THAN THAT 12-16Z PRECIP
WINDOW...CIGS WILL BE VFR ON TUESDAY...SO THE PROGRESSION OF MVFR
CIGS TO THE SW WILL HAVE TO BE WATCHED CLOSELY AS CONDITIONS MAY
BE SIGNIFICANTLY BETTER THAN CURRENTLY INDICATED...UNTIL TUESDAY
NIGHT AT LEAST.
/OUTLOOK FOR KMSP/
WED...MVFR OR LOWER CIGS/VIS WITH RA LIKELY IN AFTN. WINDS E 10KTS.
THU...MVFR/IFR CIGS WITH -RA ENDING IN MRNG. WINDS BCMG W 10-15KTS.
FRI...MVFR CIGS POSSIBLE. WINDS W 15G25KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...LS
LONG TERM...DWE
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
613 PM CDT Wed Oct 30 2013
.SHORT TERM...(This Evening through Thursday Afternoon)
Issued at 230 PM CDT WED OCT 30 2013
19Z surface analysis and visible satellite imagery depict a sharp
cold front extending from extreme NW MO to just west of Topeka to
just west of Wichita. This boundary has become nearly stationary
this afternoon, slowed by upstream pressure falls and increasing
southerly warm sector flow that has more than offset the anemic
post-frontal wind fields. The elevated mixed layer present in the
12Z KTOP sounding has been eliminating by a surge of mid-high level
subtropical moisture that overspread the area between 17-18Z per
water vapor imagery, and has resulted in widespread showers and
thunderstorms. This activity should continue to progress steadily
eastward over the next few hours, with the activity in the warm
sector diminishing and being maintained north of the warm front
across nrn MO.
Further west, satellite imagery has shown some thinning/partial clearing
along and ahead of the immediate frontal zone over eastern KS into
Kansas City. Enough insolation is expected to boost temperatures into
the lower 70s, coupled with dewpoints now in the mid 60s in the pre-
frontal moist axis. Although frontal convergence is presently weak
owing to light/calm winds on the cool side of the boundary, a short-
wave impulse over wrn KS is expected to lift across Kansas during
the late afternoon and early evening hours. Large scale ascent
associated with this feature should be sufficient for thunderstorms
to quickly develop along the frontal zone around 21-22Z. Increasing
destabilization in this region should yield SBCAPE upwards of 1500
J/kg co-located beneath an impressive mid-upper level wind field
(65-70 knots at 500mb and 120 knots at 250mb) that will shift toward
the KS/MO border by 00Z. The HRRR model, which has done extremely
well to this point, clearly shows the low level response to the upper
wave, with an increasing low level wind field this evening over ern
KS and far wrn MO, with low level SRH values increasing to between
200-300 m^2/s^s. Certainly the large scale environment would be
supportive of both supercells and smaller scale bowing segments
within a QLCS type of system. And although the warm front has become
rather diffuse from recent widespread convection, and convectively
induced boundary could also aid in the available boundary layer
vorticity. Bottom line is that we may see a period between roughly 22
and 02Z where the tornado potential becomes non-zero over the
southwest quadrant of the CWA.
In addition to the severe threat late this afternoon and early this
evening, moderate to heavy precipitation will likely train ahead of
the slow moving boundary through much of the overnight hours (and
into the day tomorrow). The deep subtropical moisture plume, with
direct connections to both the Gulf and the remnants of Hurricane
Raymond in the EPAC, have contributed to GPS measured precipitable
water column around 1.60" which is nearing the maximum values ever
recorded on this date. An intensifying low level jet this evening
and overnight will maximize rainfall efficiency by focusing moisture
transport and ascent along the frontal zone. Given that 1-2.5" of
rain has already fallen over the past 48 hours across portions of
the area, have gone ahead and issued a flash flood watch for areas
along and southeast of a St. Joseph to Trenton line, effective from
now through 18Z tomorrow.
Temperature wise, very warm and humid conditions will persist
through the warm sector overnight. Basically kept readings in the
mid 60s along and south of the MO river, with only a gradual drop
off through the 50s further north given the initial lack of cold
advection.
.LONG TERM...(Thursday Evening through Wednesday)
Issued at 230 PM CDT WED OCT 30 2013
Rain is expected to continue through the majority of the daytime
hours of Thursday as models have trended deeper and more developed
with upper energy rotating around the base of the larger trough.
Despite the surface front sinking into the southeastern third of
Missouri Thursday morning, the track of the upper wave would support
a large deformation rain band to form and spread across the CWA
through the day. Rain should finally taper off late Thursday
afternoon, leaving damp and cool conditions for Halloween evening.
Friday-Sunday: A secondary upper trough will pass through the region
on Friday ushering in slightly cooler air for Saturday. However,
mid-level ridging will quickly move eastward for the second half of
the weekend, and model guidance indicates a quick return of
southerly flow by Sunday morning. Strong warm advection should push
temperatures back into the lower 60s.
Sunday night - Wednesday: Stratus should stream northward Sunday
night, insulating the area from any extreme temperature drop. With
the next upper trough diving into the Four Corners region Monday
night, rain chances will begin to increase substantially by Tuesday
through Wednesday and have bumped up PoPs both days.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday Evening)
Issued at 608 PM CDT WED OCT 30 2013
The heaviest of the showers and thunderstorms are just about to push
east of the terminals with mainly just light showers expected at the
terminals through about 02Z-03Z with low MVFR cigs. Models and MOS
guidance suggest cigs will dip down into IFR after precipitation comes to
an end with light fog developing over the terminals reducing vsbys to
5SM. The break in precipitation should last until about 09Z-11Z when
another round of light to moderate rain will move through the
terminals and persist through the morning hours with continued IFR
cigs. Models suggest clearing tomorrow afternoon as the rain comes to
an end, this maybe be a bit optimistic however conditions should
improve to VFR. The slow moving cold front responsible for this
continued precipitation should move through the terminals between
07Z-10Z gradually veering winds from the southwest to the north-
northwest around 5-10kts.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...FLASH FLOOD WATCH through Thursday afternoon FOR KSZ025-057-060-
103>105.
MO...FLASH FLOOD WATCH through Thursday afternoon FOR MOZ007-008-
013>017-020>025-028>033-037>040-043>046-053-054.
&&
$$
SHORT TERM...Bookbinder
LONG TERM...Dux
AVIATION...73
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
959 AM CDT Tue Oct 29 2013
.MESOSCALE DISCUSSION...
Issued at 959 AM CDT TUE OCT 29 2013
Rainfall continues across the region this morning. There has been
a decrease in lightning reports over the past hour or so,
indicative of an instability starved airmass. Latest RUC forecast
indicates MLCAPE at or below 500 J/kg over much of the area for
the rest of today, thus it appears that our main issues for the
rest of this morning into this afternoon will be a few cloud to
ground lightning strikes and perhaps a storm capable of small hail
(though the risk for hail is decreasing at this time).
Rainfall has been heavy in spots and the radar estimations look to
be in the ballpark based on observed rainfall reports this
morning. Legacy precip estimations appear to most representative
at this time.
From a forecast perspective, concern is increasing for additional
rounds of heavy rainfall and an increasing risk for flooding given
observed rainfall from this morning and an increasingly moist
airmass (both Pacific and Gulf connections).
&&
.SYNOPSIS...
Issued at 237 AM CDT TUE OCT 29 2013
Water vapor was showing large upper level closed system centered
around Nevada with large Pacific moisture plume streaming from
south of the low into the southern/central Plains into the mid
Mississippi valley region. Convection developed during the mid to
late evening in the Plains as pieces over shortwave energy have
ejected out of the upper low along with a jet streak. In addition,
a 30 to 45 kt low level jet has set up from the southern into
central Plains. This convection has advanced into western Missouri
early into the overnight hours, however most of the lightning
strikes remain west of our CWA as instability is still lacking
over the area. Joplin has picked up around .13 of an inch in the
past hour.
Our main focus in the short term (today and tonight) will be with
convection and precipitation amounts. Several waves of
precipitation will be possible through Thursday as the upper low
slowly progresses eastward towards the area.
&&
.SHORT TERM...(Today and Tonight)
Issued at 237 AM CDT TUE OCT 29 2013
For today...first batch of convection (currently occurring over
the western CWA) is expected to track east across the CWA. Will
probably see scattered lightning strikes with this activity, but
overall instability will remain low and not expecting much in the
way of strong or severe storms with this first wave. Decent
precipitation totals will be possible with some locations
receiving between a half inch to inch. Isolated higher amounts
will be possible, with the higher totals expected over the
northwest half of the CWA.
There will probably be a lull in activity from late in the day
through much of the evening before convection redevelops over the
northwestern CWA during the late evening and overnight hours. If
we could get enough instability, there may be some elevated
hailers with this activity, but overall severe chances look to be
on the low side with the better instability remaining to the west.
.LONG TERM...(Wednesday through Monday)
Issued at 237 AM CDT TUE OCT 29 2013
The upper level system will begin to move into the Plains on
Wednesday with strong southerly winds continuing out ahead of this
system across the CWA. Best instability will remain south of the
area late Wednesday into Wednesday night ahead of the approaching
cold front, but convection ahead of the front during this time
frame into Thursday will offer our best chance of stronger to
possibly severe storms. No problem with the shear profiles with
this dynamic system, but the instability still looks to be on the
weaker side for any widespread severe risk. The bulk of the
precipitation should move through by 18z Thu with the pre-frontal
trough as drier air begins to work in from the west behind this.
Total clearing should take place by Thursday evening.
Widespread storm total QPF values of 1 to 3 inches are being
forecast with this slower moving system as the Pacific moisture
stream will be ongoing for much of the event, and eventual
increase in Gulf moisture as well. For now will continue the trend
of limited risk of flooding for the northwest half of the CWA
which will have the higher expectant QPF.
Generally quiet weather is expected after the passage of this
system from Thursday night through the weekend. May start to see
precipitation chances increase by early next week as another
larger trough begins to push into the Plains.
&&
.AVIATION...
Pilots flying in and out of the southwest Missouri airports will
need to monitor for low flight conditions this morning and again
late tonight.
A large cluster of showers and thunderstorms was progressing over
eastern Kansas and much of Missouri this morning. Low ceilings and
visibilities were observed at many locations, including Joplin,
Springfield, and Branson.
Additional IFR and MVFR conditions are expected this morning,
prior to improving by mid day, as the rain shifts east of the
region. Once the rain moves out of the Ozarks, expect mostly dry
weather through the afternoon, as southerly breezes persist at
around 10 mph.
Additional scattered showers and thunderstorms are expected late
tonight and into Wednesday morning. If a thunderstorms track over
one of the airports, then low flight conditions can be expected.
The intermittent stormy weather will continue into Thursday. Safe
Travels.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
MESOSCALE...Gagan
SYNOPSIS...Lindenberg
SHORT TERM...Lindenberg
LONG TERM...Lindenberg
AVIATION...Cramer
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1101 PM CDT WED OCT 30 2013
.UPDATE...
ISSUED AT 1100 PM CDT WED OCT 30 2013
AS ALREADY EVIDENCED BY AUTOMATED OBS...AREA WEBCAMS AND A
PERSONAL OBSERVATION TRAVELING TO THE WFO AT 03Z...AT LEAST
PATCHY...SHALLOW FOG HAS DEVELOPED...AND WILL LIKELY CONTINUE
DEVELOPING ACROSS MUCH OF THE CWA AS THE NIGHT WEARS ON...UNLESS
AN INCREASE IN HIGH CLOUDS IS ENOUGH TO TURN THE TIDE. PER BOTH
THE HRRR AND NAM VISIBILITY PRODUCTS...THERE IS A CHANCE THAT A
SOMEWHAT WIDESPREAD AREA OF DENSE FOG COULD EVENTUALLY MATERIALIZE
MAINLY WITHIN THE EASTERN 1/2 OF THE CWA WHERE SURFACE WINDS WILL
REMAIN THE OVERALL-LIGHTEST. WILL BE KEEPING A CLOSE EYE ON FOG
EVOLUTION...BUT AT LEAST FOR NOW HAVE INSERTED 1 MILE OR LESS
VISIBILITY WORDING INTO THE FORECAST/HAZARDOUS WEATHER OUTLOOK
IN ALL AREAS TO GET THE BALL ROLLING. IN OTHER DEPARTMENTS...HAVE
SHAVED GENERALLY 2-3 DEGREES FROM PREVIOUS LOW TEMPERATURES IN
MOST AREAS...GETTING MORE OF THE CWA DOWN INTO THE LOW-MID 30S
EXCEPT FOR UPPER 30S FAR SOUTHEAST. HAVE HARDLY LOOKED AT PRECIP
TRENDS SINCE WALKING IN THE DOOR...BUT WILL KEEP THE SLIGHT
CHANCE OF RAIN GOING ACROSS SOUTHERN ZONES.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 352 PM CDT WED OCT 30 2013
THE CWA CONTINUES TO SIT UNDER SOUTHWESTERLY FLOW IN THE UPPER
LEVELS...WITH THE MAIN LOW LOCATED ROUGHLY OVER THE WY/SD/NE
BORDER AREA...AND TROUGH AXIS EXTENDING TO THE S/SW. THE
SHORTWAVE DISTURBANCE WHICH BROUGHT SOME STRONG/SVR THUNDERSTORMS
EARLY THIS MORNING HAS SHIFTED OFF TO THE EAST OF THE AREA...AND
OUTSIDE OF A FEW LINGERING SHOWERS AND PATCHY DRIZZLE THROUGH THE
EARLY AFTERNOON...THERE HASNT BEEN A WHOLE LOT GOING ON TODAY.
AFTER STARTING THE DAY COMPLETELY SOCKED IN WITH LOW LEVEL STRATUS
AND CEILINGS ARND 500FT...CLOUDS ARE STARTING TO BREAK UP A
BIT...WITH THE NW CURRENTLY SEEING SOME DECENT SUN...WITH CEILINGS
ELSEWHERE STARTING TO LIFT. SURFACE HIGH PRESSURE HAS SETTLED INTO
THE REGION...KEEPING WINDS NORTHWESTERLY AND ON THE LIGHTER SIDE.
BETTER CHANCES FOR PRECIPITATION HAVE SHIFTED EAST...SO HAVE
REMOVED POPS THE REST OF THIS AFTERNOON/EARLY EVENING.
LOOKING AT TONIGHT AND INTO TOMORROW MORNING...THERE ARE A COUPLE
OF CONCERNS. MAIN ONE IS WITH ANOTHER UPPER LEVEL SHORTWAVE
DISTURBANCE EXPECTED TO PUSH OUT OF THE FOUR CORNERS
REGION...SLIDING ACROSS KS. DECIDED TO INSERT A SLIGHT CHANCE POP
ACROSS OUR NC KS COUNTIES LATER THIS EVENING INTO TOMORROW
MORNING...WITH MOST MODELS SHOWING THAT POTENTIAL BEING THERE. NOT
ALL AGREE...AND KEEP ACTIVITY JUST TO THE SOUTH. ANOTHER CONCERN
IS WITH SOME PATCHY FOG...AS SURFACE HIGH PRESSURE REMAINS IN THE
AREA AND WINDS STAY ON THE LIGHTER SIDE. WILL HOLD OFF ON MENTION
FOR NOW...WITH MODELS SHOWING SOME DRIER AIR STARTING TO WORK IN
FROM THE WEST...BUT EVENING CREW WILL HAVE TO KEEP AN EYE ON
IT...AND SEE IF ANYTHING DEVELOPS ALONG A SURFACE BOUNDARY THAT
WILL BE MAKING ITS WAY INTO THE CWA.
THROUGH THE REST OF THE DAYTIME HOURS...ANY PRECIPITATION THAT
DOES WORK INTO NC KS IS EXPECTED TO BE OFF TO THE EAST BY MIDDAY
AS THE MAIN MID/UPPER LEVEL TROUGH AXIS SWINGS THROUGH...WITH THE
REST OF THE AFTERNOON DRY. A REINFORCING SHOT OF NORTHWESTERLY
WINDS IS EXPECTED AS THE TROUGH MOVES THROUGH...AND A BREEZY
AFTERNOON IS EXPECTED...WITH SPEEDS IN THE 15 TO 25 MPH RANGE. AS
FAR AS TEMPERATURES GO...THE DOWNSLOPING COMPONENT TO THE WINDS
ALONG WITH A SLIGHT BUMP UP IN TEMPS ALOFT IS EXPECTED TO RESULT
IN HIGHS IN THE MID 50S IN THE NORTHEAST TO LOW 60S IN THE
SOUTHWEST.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 352 PM CDT WED OCT 30 2013
BY THURSDAY EVENING...THE MAIN UPPER LEVEL TROUGH WILL SHIFT EAST
OF THE REGION...WHILE A STRONG UPPER LEVEL RIDGE SLIDES INLAND ON
THE WEST COAST. A SECONDARY WEAKER WAVE WILL TRANSCEND SOUTH
ACROSS THE TROUGH AXIS THROUGHOUT THE DAY ON FRIDAY. AT THE
SURFACE...LOW PRESSURE TO THE EAST AND HIGH PRESSURE ALONG THE
WEST COAST WILL GENERATE A TIGHT PRESSURE GRADIENT ACROSS THE
PLAINS. THEREFORE...EXPECTING STRONGER NORTHWEST WINDS ACROSS THE
REGION ON FRIDAY...COMBINED WITH DECREASING DEWPOINTS. HEADING
INTO THE WEEKEND...EXPECT THE UPPER LEVEL RIDGE TO SHIFT EASTWARD.
SURFACE HIGH PRESSURE WILL KEEP THINGS FAIRLY QUIET ACROSS THE
PLAINS WITH MOSTLY SUNNY SKIES AND TEMPERATURES IN THE 50S TO 60S.
THE NEXT UPPER LEVEL WAVE/TROUGH IS ON TAP FOR MONDAY INTO
TUESDAY...AS A STRONG UPPER LEVEL WAVE DIVES SOUTHWEST FROM
BRITISH COLUMBIA INTO IDAHO AND MONTANA. THE GFS SOLUTIONS
REMAINS A BIT MORE BROAD WITH THE WAVE AND NOT AS DEEP AS THE
ECMWF SOLUTION...ALTHOUGH NEITHER BECOME CLOSED AT 500 MB. AT THE
SURFACE...TWO AREAS OF LOW PRESSURE...ONE ALONG THE FRONT RANGE
AND A SECOND ACROSS SOUTHERN CANADA WILL DRAG A COLD FRONT THROUGH
THE AREA SOMETIME MONDAY MORNING. AGAIN...TIMING REMAINS A BIT
UNCERTAIN BETWEEN THE TWO LONG TERM MODEL SOLUTIONS. BEHIND THE
FRONT...COLDER 850 MB AIR WILL BEGIN TO INFILTRATE THE REGION.
BOTH MODELS DO INDICATE SOME PRECIPITATION AROUND THE REGION
MONDAY NIGHT...BUT THE ECMWF SUGGESTS A MORE EXPANSIVE AREA. AT
THIS TIME...CURRENT THINKING...SHOULD PRECIPITATION BE REALIZED
BEHIND THE FRONT...TEMPERATURES ALOFT SHOULD BE COLD ENOUGH FOR AT
LEAST A RAIN SNOW MIX ESPECIALLY ACROSS NORTHWESTERN ZONES.
UNTIL THE TROUGH AXIS FINALLY SHIFTS ACROSS THE PLAINS BY
WEDNESDAY...COOLER AIR WILL CONTINUE TO TAKE HOLD ACROSS THE
PLAINS. AS SUCH...EXPECT HIGH TEMPERATURES TO DROP INTO THE LOWER
50S...POSSIBLY EVEN 40S FOR HIGHS FOR THE BEGINNING OF THE
WORKWEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 635 PM CDT WED OCT 30 2013
SOME LINGERING STRATUS WILL MAKE CEILING PREDICTION A TOUGH CALL
FOR THE FIRST PART OF THE FORECAST. THE TERMINAL IS ALONG THE EDGE
AS IT MOVES OUT...SO A TEMPO OF A COUPLE OF HOURS FOR STRATUS WAS
PUT IN...BUT WE COULD HOLD ON TO THE STRATUS A BIT LONGER. A FEW
MID-HIGH LEVEL CLOUDS COULD CREEP IN TOMORROW AS THE FINAL WAVE
MOVES THROUGH.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...PFANNKUCH
SHORT TERM...ADO
LONG TERM...SALTZMAN
AVIATION...HEINLEIN
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1251 PM CDT TUE OCT 29 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 338 AM CDT TUE OCT 29 2013
THE DEEP H500 MB UPPER LEVEL LOW ACROSS THE WESTERN U.S. IS
EXPECTED TO LIFT SLOWLY NORTHEAST INTO WRN WY BY 12Z WEDNESDAY.
THE MODELS ARE STRENGTHENING THE WARM AIR ADVECTION FROM 850 MB TO
700 MB AS THE LOW LIFTS NORTH BUT REMAIN WEST OF THE FORECAST
AREA. THUS THE THREAT OF FREEZING PRECIPITATION WOULD APPEAR TO BE
DECREASING SOMEWHAT. THE MODELS SHOW A STRONG DRY SLOW WORKING
INTO THE FCST AREA BETWEEN 850-700MB DURING THE DAY TODAY. AS THE
UPPER LEVEL COLD POOL NOSES INTO WYOMING TONIGHT...STEEPENING
LAPSES MIGHT SUPPORT AN ORGANIZED ROUND OF ACCUMULATING ICE ACROSS
THE PANHANDLE AND PERHAPS INTO WESTERN NEBRASKA. TEMPERATURES AT
700 MB IN THESE AREAS COOL TO -2C TO -4C WHICH WOULD NOT SUPPORT
RAPID SNOW GROWTH AND GIVEN THE STRENGTHENING WARM AIR ADVECTION
AT 850MB...ALL MODELS ARE ABOVE FREEZING 1C TO 4C...FREEZING RAIN
WOULD APPEAR TO BE THE ONLY THREAT.
NOTE THE BEST GUESS AT MIN TEMPERATURES WEDNESDAY MORNING PRODUCED
LOWS NEAR 30 ACROSS THE NORTHWEST ZONES WITH A FREEZING LINE RUNNING
FROM ROUGHLY BIG SPRINGS TO AINSWORTH. HIGHS TODAY RISE TO THE MID
30S ACROSS SHERIDAN AND CHERRY COUNTIES. THE RAP MODEL PRODUCED
HIGHS AROUND 33 IN THAT AREA THIS AFTERNOON AND THE HRRR SHOWED 35F.
WITH LOWS FALLING TO AROUND 30 TONIGHT...IT WOULD APPEAR ABOUT 8 TO
10 HOURS OF SUBFREEZING WEATHER COULD DEVELOP WHICH WOULD
NECESSITATE ANOTHER WINTER WEATHER ADVISORY ACROSS SHERIDAN AND
CHERRY COUNTIES. TEMPERATURES TODAY SHOULD RISE ABOVE THE FREEZING
MARK AROUND NOON IN THIS AREA AND WE ARE FORECASTING WARMER LOWS
TONIGHT THAN ARE OCCURRING THIS MORNING.
GIVEN THE DRY AIR MOVING IN ALOFT AHEAD OF THE UPPER LOW...FOG COULD
BECOME A BIT MORE WIDESPREAD TONIGHT BUT MAINLY EAST OF HIGHWAY 83
AS SUGGESTED IN THE 850-700MB MOISTURE FIELDS. DRIZZLE WOULD APPEAR
TO BE THE OPERATIVE PRECIPITATION MODE WITH THE SHALLOW MOISTURE
PROFILES ALONG AND EAST OF HIGHWAY 83 BUT SOME SOLNS LIKE THE GFS
DEVELOP WIDESPREAD LIGHT RAIN ALONG AND EAST OF HIGHWAY 83. THE
OTHER MODELS DO THE SAME BUT ARE FARTHER EAST FAVORING CENTRAL AND
EASTERN NEB WITH THIS RAIN. IT LOOKS LIKES THE GFS IS MAINTAINING A
STRONGLY BACK LOW LEVEL FLOW TONIGHT WHILE THE NAM FOR EXAMPLE VEERS
THE 850 WINDS A BIT MORE TOWARD ERN NEB. THE 305K ISENTROPIC
MOISTURE TRANSPORT VECTORS IN BOTH MODELS IS DIRECTED TOWARD EASTERN
AND CNTL NEB.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 338 AM CDT TUE OCT 29 2013
STORM SYSTEM WILL CONTINUE MOVING THROUGH THE CENTRAL AND NORTHERN
PLAINS DURING THE DAY WEDNESDAY...EXITING TO THE NORTHEAST WEDNESDAY
NIGHT. AS THE UPPER TROUGH AXIS CROSSES THE AREA WEDNESDAY...SHOWERS
WILL CONTINUE TO BE POSSIBLE.
WARM AIR IN THE MID LEVELS OF THE ATMOSPHERE WILL CONTINUE TO KEEP
MOST OF THE PRECIPITATION IN LIQUID FORM. REALLY LITTLE CHANCE OF
SNOW...AS ALL MODELS KEEP TEMPERATURES AT 850MB ABOVE FREEZING. AT
THE SURFACE HOWEVER...SHALLOW ARCTIC AIR WILL REMAIN ACROSS THE
AREA...WITH TEMPERATURES WEDNESDAY MORNING NEAR OR A FEW DEGREES
BELOW FREEZING ACROSS PORTIONS OF NORTHERN AND NORTHWEST NEBRASKA.
FREEZING RAIN WILL LIKELY BEGIN THE DAY...BUT WILL QUICKLY CHANGE TO
RAIN AS TEMPERATURES WARM ABOVE FREEZING BY MID MORNING. FARTHER
EAST ACROSS CENTRAL AND SOUTHWEST NEBRASKA...SUFFICIENT MID LEVEL
INSTABILITY WARRANTS A THUNDER MENTION DURING THE MORNING. BY
AFTERNOON...DRY AIR IN THE MID LEVELS SPREADS NORTHEAST...ENDING
PRECIPITATION FROM SOUTHWEST TO NORTHEAST. SKIES BEGIN TO CLEAR
WEDNESDAY NIGHT...WITH DOWNSLOPE FLOW AND SUNNY SKIES BOOSTING
HIGHS THURSDAY INTO THE 50S TO NEAR 60.
DRY AND MILD WEATHER WILL CONTINUE THROUGH THE WEEKEND...AHEAD OF
THE NEXT UPPER TROUGH AND POTENTIAL PRECIPITATION EARLY NEXT
WEEK. DETAILS REMAIN SKETCHY WITH THIS NEXT SYSTEM...AND WILL ONLY
CARRY SLIGHT CHANCES FOR RAIN/SNOW AT THIS TIME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1250 PM CDT TUE OCT 29 2013
WIDESPREAD IFR OR LIFR CONDITIONS EXPECTED TO CONTINUE THE NEXT
24 HOURS. PLENTIFUL MOISTURE IS TRAPPED IN THE BOUNDARY LAYER
WITH MODELS IN GOOD AGREEMENT RESULTING IN HIGH CONFIDENCE OF
CIGS REMAINS BELOW OVC010. BETTER LIFT WITHIN THE BOUNDARY LAYER
RESULTING IN SCT SHOWERS EAST OF HIGHWAY 83...OTHERWISE AREAS OF
DRIZZLE AND FOG WILL DOMINATE. TEMPERATURES TONIGHT ACROSS NW NEB
DROP TO OR BELOW FREEZING WITH THE POSSIBILITY OF FREEZING
PRECIP/LIGHT ICING. IMPACT AT THE KVTN TERMINAL IS
POSSIBLE...HOWEVER EXPECT KLBF TO REMAIN WARM ENOUGH FOR LIQUID
PRECIP.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...MASEK
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
620 AM CDT TUE OCT 29 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 338 AM CDT TUE OCT 29 2013
THE DEEP H500 MB UPPER LEVEL LOW ACROSS THE WESTERN U.S. IS
EXPECTED TO LIFT SLOWLY NORTHEAST INTO WRN WY BY 12Z WEDNESDAY.
THE MODELS ARE STRENGTHENING THE WARM AIR ADVECTION FROM 850 MB TO
700 MB AS THE LOW LIFTS NORTH BUT REMAIN WEST OF THE FORECAST
AREA. THUS THE THREAT OF FREEZING PRECIPITATION WOULD APPEAR TO BE
DECREASING SOMEWHAT. THE MODELS SHOW A STRONG DRY SLOW WORKING
INTO THE FCST AREA BETWEEN 850-700MB DURING THE DAY TODAY. AS THE
UPPER LEVEL COLD POOL NOSES INTO WYOMING TONIGHT...STEEPENING
LAPSES MIGHT SUPPORT AN ORGANIZED ROUND OF ACCUMULATING ICE ACROSS
THE PANHANDLE AND PERHAPS INTO WESTERN NEBRASKA. TEMPERATURES AT
700 MB IN THESE AREAS COOL TO -2C TO -4C WHICH WOULD NOT SUPPORT
RAPID SNOW GROWTH AND GIVEN THE STRENGTHENING WARM AIR ADVECTION
AT 850MB...ALL MODELS ARE ABOVE FREEZING 1C TO 4C...FREEZING RAIN
WOULD APPEAR TO BE THE ONLY THREAT.
NOTE THE BEST GUESS AT MIN TEMPERATURES WEDNESDAY MORNING PRODUCED
LOWS NEAR 30 ACROSS THE NORTHWEST ZONES WITH A FREEZING LINE RUNNING
FROM ROUGHLY BIG SPRINGS TO AINSWORTH. HIGHS TODAY RISE TO THE MID
30S ACROSS SHERIDAN AND CHERRY COUNTIES. THE RAP MODEL PRODUCED
HIGHS AROUND 33 IN THAT AREA THIS AFTERNOON AND THE HRRR SHOWED 35F.
WITH LOWS FALLING TO AROUND 30 TONIGHT...IT WOULD APPEAR ABOUT 8 TO
10 HOURS OF SUBFREEZING WEATHER COULD DEVELOP WHICH WOULD
NECESSITATE ANOTHER WINTER WEATHER ADVISORY ACROSS SHERIDAN AND
CHERRY COUNTIES. TEMPERATURES TODAY SHOULD RISE ABOVE THE FREEZING
MARK AROUND NOON IN THIS AREA AND WE ARE FORECASTING WARMER LOWS
TONIGHT THAN ARE OCCURRING THIS MORNING.
GIVEN THE DRY AIR MOVING IN ALOFT AHEAD OF THE UPPER LOW...FOG COULD
BECOME A BIT MORE WIDESPREAD TONIGHT BUT MAINLY EAST OF HIGHWAY 83
AS SUGGESTED IN THE 850-700MB MOISTURE FIELDS. DRIZZLE WOULD APPEAR
TO BE THE OPERATIVE PRECIPITATION MODE WITH THE SHALLOW MOISTURE
PROFILES ALONG AND EAST OF HIGHWAY 83 BUT SOME SOLNS LIKE THE GFS
DEVELOP WIDESPREAD LIGHT RAIN ALONG AND EAST OF HIGHWAY 83. THE
OTHER MODELS DO THE SAME BUT ARE FARTHER EAST FAVORING CENTRAL AND
EASTERN NEB WITH THIS RAIN. IT LOOKS LIKES THE GFS IS MAINTAINING A
STRONGLY BACK LOW LEVEL FLOW TONIGHT WHILE THE NAM FOR EXAMPLE VEERS
THE 850 WINDS A BIT MORE TOWARD ERN NEB. THE 305K ISENTROPIC
MOISTURE TRANSPORT VECTORS IN BOTH MODELS IS DIRECTED TOWARD EASTERN
AND CNTL NEB.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 338 AM CDT TUE OCT 29 2013
STORM SYSTEM WILL CONTINUE MOVING THROUGH THE CENTRAL AND NORTHERN
PLAINS DURING THE DAY WEDNESDAY...EXITING TO THE NORTHEAST WEDNESDAY
NIGHT. AS THE UPPER TROUGH AXIS CROSSES THE AREA WEDNESDAY...SHOWERS
WILL CONTINUE TO BE POSSIBLE.
WARM AIR IN THE MID LEVELS OF THE ATMOSPHERE WILL CONTINUE TO KEEP
MOST OF THE PRECIPITATION IN LIQUID FORM. REALLY LITTLE CHANCE OF
SNOW...AS ALL MODELS KEEP TEMPERATURES AT 850MB ABOVE FREEZING. AT
THE SURFACE HOWEVER...SHALLOW ARCTIC AIR WILL REMAIN ACROSS THE
AREA...WITH TEMPERATURES WEDNESDAY MORNING NEAR OR A FEW DEGREES
BELOW FREEZING ACROSS PORTIONS OF NORTHERN AND NORTHWEST NEBRASKA.
FREEZING RAIN WILL LIKELY BEGIN THE DAY...BUT WILL QUICKLY CHANGE TO
RAIN AS TEMPERATURES WARM ABOVE FREEZING BY MID MORNING. FARTHER
EAST ACROSS CENTRAL AND SOUTHWEST NEBRASKA...SUFFICIENT MID LEVEL
INSTABILITY WARRANTS A THUNDER MENTION DURING THE MORNING. BY
AFTERNOON...DRY AIR IN THE MID LEVELS SPREADS NORTHEAST...ENDING
PRECIPITATION FROM SOUTHWEST TO NORTHEAST. SKIES BEGIN TO CLEAR
WEDNESDAY NIGHT...WITH DOWNSLOPE FLOW AND SUNNY SKIES BOOSTING
HIGHS THURSDAY INTO THE 50S TO NEAR 60.
DRY AND MILD WEATHER WILL CONTINUE THROUGH THE WEEKEND...AHEAD OF
THE NEXT UPPER TROUGH AND POTENTIAL PRECIPITATION EARLY NEXT
WEEK. DETAILS REMAIN SKETCHY WITH THIS NEXT SYSTEM...AND WILL ONLY
CARRY SLIGHT CHANCES FOR RAIN/SNOW AT THIS TIME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 614 AM CDT TUE OCT 29 2013
WIDESPREAD IFR CONTINUES TODAY AND TONIGHT WITH UPSLOPE MOISTURE
HOLDING CEILINGS LOW. A PERIOD OF MVFR IS EXPECTED LATE THIS
MORNING THROUGH LATE THIS AFTERNOON ALONG AND EAST OF HIGHWAY 83.
LOW CEILINGS ARE EXPECTED TONIGHT AS EASTERLY WINDS CONTINUE. AN
UPPER LEVEL LOW...CURRENTLY ACROSS THE SWRN U.S....WILL LIFT NORTH
INTO WYOMING. AS THIS OCCURS...ADDITIONAL SHOWERS AND ISOLATED
TSTMS SHOULD REDEVELOP. FREEZING DRIZZLE OR FREEZING RAIN IS
EXPECTED TO REDEVELOP TONIGHT ACROSS NORTHWEST NEBRASKA.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON CDT /11 AM MDT/ TODAY FOR
NEZ004-005-094.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
344 AM CDT TUE OCT 29 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 338 AM CDT TUE OCT 29 2013
THE DEEP H500 MB UPPER LEVEL LOW ACROSS THE WESTERN U.S. IS
EXPECTED TO LIFT SLOWLY NORTHEAST INTO WRN WY BY 12Z WEDNESDAY.
THE MODELS ARE STRENGTHENING THE WARM AIR ADVECTION FROM 850 MB TO
700 MB AS THE LOW LIFTS NORTH BUT REMAIN WEST OF THE FORECAST
AREA. THUS THE THREAT OF FREEZING PRECIPITATION WOULD APPEAR TO BE
DECREASING SOMEWHAT. THE MODELS SHOW A STRONG DRY SLOW WORKING
INTO THE FCST AREA BETWEEN 850-700MB DURING THE DAY TODAY. AS THE
UPPER LEVEL COLD POOL NOSES INTO WYOMING TONIGHT...STEEPENING
LAPSES MIGHT SUPPORT AN ORGANIZED ROUND OF ACCUMULATING ICE ACROSS
THE PANHANDLE AND PERHAPS INTO WESTERN NEBRASKA. TEMPERATURES AT
700 MB IN THESE AREAS COOL TO -2C TO -4C WHICH WOULD NOT SUPPORT
RAPID SNOW GROWTH AND GIVEN THE STRENGTHENING WARM AIR ADVECTION
AT 850MB...ALL MODELS ARE ABOVE FREEZING 1C TO 4C...FREEZING RAIN
WOULD APPEAR TO BE THE ONLY THREAT.
NOTE THE BEST GUESS AT MIN TEMPERATURES WEDNESDAY MORNING PRODUCED
LOWS NEAR 30 ACROSS THE NORTHWEST ZONES WITH A FREEZING LINE RUNNING
FROM ROUGHLY BIG SPRINGS TO AINSWORTH. HIGHS TODAY RISE TO THE MID
30S ACROSS SHERIDAN AND CHERRY COUNTIES. THE RAP MODEL PRODUCED
HIGHS AROUND 33 IN THAT AREA THIS AFTERNOON AND THE HRRR SHOWED 35F.
WITH LOWS FALLING TO AROUND 30 TONIGHT...IT WOULD APPEAR ABOUT 8 TO
10 HOURS OF SUBFREEZING WEATHER COULD DEVELOP WHICH WOULD
NECESSITATE ANOTHER WINTER WEATHER ADVISORY ACROSS SHERIDAN AND
CHERRY COUNTIES. TEMPERATURES TODAY SHOULD RISE ABOVE THE FREEZING
MARK AROUND NOON IN THIS AREA AND WE ARE FORECASTING WARMER LOWS
TONIGHT THAN ARE OCCURRING THIS MORNING.
GIVEN THE DRY AIR MOVING IN ALOFT AHEAD OF THE UPPER LOW...FOG COULD
BECOME A BIT MORE WIDESPREAD TONIGHT BUT MAINLY EAST OF HIGHWAY 83
AS SUGGESTED IN THE 850-700MB MOISTURE FIELDS. DRIZZLE WOULD APPEAR
TO BE THE OPERATIVE PRECIPITATION MODE WITH THE SHALLOW MOISTURE
PROFILES ALONG AND EAST OF HIGHWAY 83 BUT SOME SOLNS LIKE THE GFS
DEVELOP WIDESPREAD LIGHT RAIN ALONG AND EAST OF HIGHWAY 83. THE
OTHER MODELS DO THE SAME BUT ARE FARTHER EAST FAVORING CENTRAL AND
EASTERN NEB WITH THIS RAIN. IT LOOKS LIKES THE GFS IS MAINTAINING A
STRONGLY BACK LOW LEVEL FLOW TONIGHT WHILE THE NAM FOR EXAMPLE VEERS
THE 850 WINDS A BIT MORE TOWARD ERN NEB. THE 305K ISENTROPIC
MOISTURE TRANSPORT VECTORS IN BOTH MODELS IS DIRECTED TOWARD EASTERN
AND CNTL NEB.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 338 AM CDT TUE OCT 29 2013
STORM SYSTEM WILL CONTINUE MOVING THROUGH THE CENTRAL AND NORTHERN
PLAINS DURING THE DAY WEDNESDAY...EXITING TO THE NORTHEAST WEDNESDAY
NIGHT. AS THE UPPER TROUGH AXIS CROSSES THE AREA WEDNESDAY...SHOWERS
WILL CONTINUE TO BE POSSIBLE.
WARM AIR IN THE MID LEVELS OF THE ATMOSPHERE WILL CONTINUE TO KEEP
MOST OF THE PRECIPITATION IN LIQUID FORM. REALLY LITTLE CHANCE OF
SNOW...AS ALL MODELS KEEP TEMPERATURES AT 850MB ABOVE FREEZING. AT
THE SURFACE HOWEVER...SHALLOW ARCTIC AIR WILL REMAIN ACROSS THE
AREA...WITH TEMPERATURES WEDNESDAY MORNING NEAR OR A FEW DEGREES
BELOW FREEZING ACROSS PORTIONS OF NORTHERN AND NORTHWEST NEBRASKA.
FREEZING RAIN WILL LIKELY BEGIN THE DAY...BUT WILL QUICKLY CHANGE TO
RAIN AS TEMPERATURES WARM ABOVE FREEZING BY MID MORNING. FARTHER
EAST ACROSS CENTRAL AND SOUTHWEST NEBRASKA...SUFFICIENT MID LEVEL
INSTABILITY WARRANTS A THUNDER MENTION DURING THE MORNING. BY
AFTERNOON...DRY AIR IN THE MID LEVELS SPREADS NORTHEAST...ENDING
PRECIPITATION FROM SOUTHWEST TO NORTHEAST. SKIES BEGIN TO CLEAR
WEDNESDAY NIGHT...WITH DOWNSLOPE FLOW AND SUNNY SKIES BOOSTING
HIGHS THURSDAY INTO THE 50S TO NEAR 60.
DRY AND MILD WEATHER WILL CONTINUE THROUGH THE WEEKEND...AHEAD OF
THE NEXT UPPER TROUGH AND POTENTIAL PRECIPITATION EARLY NEXT
WEEK. DETAILS REMAIN SKETCHY WITH THIS NEXT SYSTEM...AND WILL ONLY
CARRY SLIGHT CHANCES FOR RAIN/SNOW AT THIS TIME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1151 PM CDT MON OCT 28 2013
WITH MARGINAL TEMPERATURES...THERE IS CONSIDERABLE UNCERTAINTY OVER
WHETHER PRECIPITATION WILL BE FROZEN...FREEZING OR LIQUID IN A LARGE
PART OF NORTH CENTRAL AND NORTHWEST NEBRASKA.
OTHERWISE...CEILINGS IN WESTERN NEBRASKA ARE 500-1000 FEET AGL WITH
A FEW BELOW 500 FEET. ALSO...AREAS OF DRIZZLE OR LIGHT RAIN WILL
CONTINUE THROUGH THE NIGHT. IN NORTHERN NEBRASKA...WHICH INCLUDES
ANW...VTN...TIF AND MHN...FREEZING DRIZZLE OR LIGHT FREEZING RAIN IS
LIKELY. IN THE FAR NORTH...THAT IS VTN AND ANW...FREEZING
RAIN/DRIZZLE MAY MIX WITH OR CHANGE OVER BRIEFLY TO SNOW. AFTER 16Z
WHEN TEMPERATURES RISE ABOVE 32F...IT IS ALL EXPECTED TO BE LIQUID.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON CDT /11 AM MDT/ TODAY FOR
NEZ004-005-094.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...SPRINGER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1015 PM CDT WED OCT 30 2013
.UPDATE...
ISSUED AT 1000 PM CDT WED OCT 30 2013
LATE EVENING UPDATE FOR SKY COVER AND TEMPERATURE TRENDS. CLEARING
HAS ADVANCED FARTHER EAST THAN PREVIOUSLY FORECAST WITH MOST OF
THE STRATUS NOW LOCATED EAST OF THE MISSOURI RIVER. THE RAP NOW
HAS A GOOD HANDLE ON THE LOW LEVEL RH...AND SUGGESTS THERE MAY BE
SOME LOW CLOUDS FILL BACK IN OVER THE SOUTHWEST AFTER MIDNIGHT.
PATCHY DRIZZLE/FREEZING DRIZZLE SHOULD REMAIN CONFINED TO THE FAR
SOUTHEAST BUT NO SIGNIFICANT TRAVEL IMPACTS EXPECTED. MAINTAINED
PATCHY FOG IN THE FORECAST GRIDS OVERNIGHT...ALTHOUGH WINDS SHOULD
STAY UP ENOUGH TO PREVENT WIDESPREAD DENSE FOG.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 240 PM CDT WED OCT 30 2013
FORECAST CHALLENGES/HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE
STRATUS AND PATCHY FOG TONIGHT...ALONG WITH LIGHT DRIZZLE/FREEZING
DRIZZLE SOUTH THROUGH THIS EVENING.
CURRENTLY...BROAD UPPER LOW MOVING INTO THE CENTRAL PLAINS WITHIN
A LONG WAVE TROUGH ACROSS THE CENTRAL UNITED STATES. ENERGY
ROTATING THROUGH THE TROUGH AND AHEAD OF THE LOW GENERATING A BAND
OF LIGHT PRECIPITATION ACROSS FAR NORTHERN SOUTH DAKOTA PUSHING
NORTH TOWARDS MY SOUTHERN COUNTIES. WILL MAINTAIN PATCHY/AREAS OF
DRIZZLE/FREEZING DRIZZLE INTO THIS EVENING SOUTH OF I94. STRATUS
AND RESULTANT TEMPERATURES HAVE BEEN A STRUGGLE TODAY WITH MODELS
NOT PERFORMING VERY WELL IN DEPICTING THE AERIAL COVERAGE OF THE
LOW CLOUDS WITH THE STRATUS DECK PERSISTING LONG AFTER MODELS
INDICATED CLEARING.
IF FREEZING DRIZZLE IS INDEED OCCURRING THIS AFTERNOON WHERE AIR
TEMPERATURES ARE 32F OR LESS...DO NOT ANTICIPATE ANY IMPACTS WITH
ROAD SURFACE TEMPERATURES IN THE UPPER 30S OR WARMER. MAY SEE MORE
IMPACTS THIS EVENING AS ROAD SFC TEMPERATURES DROP SO WILL NEED TO
MONITOR. BY 06Z THE UPPER LOW WILL BE OVER CENTRAL SOUTH DAKOTA
WITH ALL ASSOCIATED LIFT MOVING EAST OUT OF SOUTHWEST AND SOUTH
CENTRAL NORTH DAKOTA SO KEPT THE OVERNIGHT DRY. BOTH THE GFS/NAM
MAINTAIN HIGH BOUNDARY LAYER RH THROUGH TONIGHT SO WILL KEEP THE
FORECAST CLOUDY UNTIL MID MORNING THURSDAY WHEN A DECENT
WEST/NORTHWEST WIND SHOULD SCATTER OUT THE LOW CIGS. PATCHY FOG
USUALLY ACCOMPANIES STRATUS SO WILL MAINTAIN THIS INTO THE
FORECAST TONIGHT.
WITH A BETTER POTENTIAL FOR CLEARING THURSDAY...SHOULD SEE WARMER
TEMPERATURES IN THE 40S. EMBEDDED ENERGY IN NORTHWEST FLOW ALOFT
DOES MOVE INTO THE NORTHERN PLAINS THURSDAY MORNING/AFTERNOON.
HOWEVER...LITTLE SURFACE FORCING IN PLACE SO WILL MAINTAIN A DRY
FORECAST WITH AN INCREASE IN MID/UPPER LEVEL CLOUDS THE ONLY
NOTICEABLE WEATHER WITH THE WAVE.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 240 PM CDT WED OCT 30 2013
THE HIGHLIGHT OF THE EXTENDED IS A WARM UP THROUGH THE
WEEKEND...AND WINDY CONDITIONS ON FRIDAY.
THE 12 UTC GUIDANCE SUITE IS IN GOOD AGREEMENT ON NORTHWEST FLOW
ALOFT ACROSS THE NORTHERN PLAINS THURSDAY NIGHT THROUGH
FRIDAY...BEFORE AN UPPER LEVEL RIDGE BUILDS ACROSS THE REGION
SATURDAY AND SUNDAY. A WEAK CLIPPER IS FORECAST TO PROPAGATE
ACROSS WESTERN AND CENTRAL NORTH DAKOTA ON FRIDAY. THERE IS A
SLIGHT CHANCE OF A RAIN AND SNOW MIX FRIDAY MORNING TRANSITIONING
TO ALL RAIN THROUGH THE DAY IN ASSOCIATION WITH THE UPPER LEVEL
WAVE. WINDY CONDITIONS ARE ALSO POSSIBLE ON FRIDAY ON THE BACKSIDE
OF THE CLIPPER. AT THIS TIME...THE BEST CHANCE FOR ADVISORY LEVEL
WINDS ARE ACROSS THE FAR SOUTHWEST. NEAR NORMAL TEMPERATURES IN THE
MID TO UPPER 40S...PERHAPS THE LOWER 50S NEAR THE SOUTH DAKOTA
BORDER...ARE EXPECTED SATURDAY AND SUNDAY UNDER THE AFOREMENTIONED
RIDGE. HOWEVER...ANOTHER COOL DOWN IS SUGGESTED ON THE 12 UTC
DETERMINISTIC MODELS ON MONDAY AS A COLD FRONT PROPAGATES ACROSS
THE NORTHERN PLAINS AS THE UPPER LEVEL RIDGE SHIFTS TO THE EASTERN
CONUS WITH A DIGGING INTERMOUNTAIN WEST LONG WAVE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1000 PM CDT WED OCT 30 2013
LATE EVENING UPDATES TO TAFS FOR CLEARING TREND. STRATUS EXPECTED
TO FILL BACK IN OVERNIGHT AT KDIK. MAINLY MVFR FOG ALSO POSSIBLE
AT ALL TAF SITES.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE/AVIATION...RP KINNEY
SHORT TERM...NH
LONG TERM...AYD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
928 PM CDT WED OCT 30 2013
.UPDATE...
ISSUED AT 928 PM CDT WED OCT 30 2013
VISIBILITIES DUE TO FOG CONTINUE TO LOWER ACROSS PORTIONS OF WEST
CENTRAL MINNESOTA THIS EVENING. ALTHOUGH 925MB-850MB WINDS ARE
EXPECTED TO INCREASE AFTER MIDNIGHT...NOT SEEING MUCH SURFACE
PRESSURE GRADIENT INCREASE UNTIL CLOSER TO NOON ON THURSDAY. THE
RAP/HRRR HAVE INDICATED LIGHT SURFACE WINDS THROUGH MID-MORNING
ALONG WITH HIGH LOW LEVEL MOISTURE (AND VISIBILITIES 1/4 MILE OR
LESS). FOR THESE REASONS...HAVE ISSUED A DENSE FOG ADVISORY FOR
THIS AREA UNTIL 10AM THURSDAY. WE HAVE RECEIVED A FEW REPORTS OF
DENSE FOG ALREADY...AND DO NOT EXPECT CONDITIONS TO IMPROVE
ANYTIME SOON.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 345 PM CDT WED OCT 30 2013
CHALLENGES FOR THE FORECAST INCLUDE TEMPS AND ENDING TIME OF THE
DRIZZLE/LIGHT RAIN OVERNIGHT INTO TOMORROW MORNING. MODELS IN FAIR
AGREEMENT WITH THIS PERIOD AND WILL USE A BLEND FOR THE FORECAST.
THIS EVENING WILL CONTINUE TO SEE VERY WEAK LOW LEVEL MOISTURE/TEMP
ADVECTION IN THE SE THIRD OF THE FA. TOWARD 06Z 850MB WINDS
INCREASE AND BECOME S TO SWERLY. ALSO SFC WINDS WILL TURN TO THE
WEST ALTHOUGH REMAIN LIGHT. DID ADD A MENTION OF PATCHY FOG
OVERNIGHT WITH SATURATED AIRMASS AND THE FOG OCCURRENCE THE PAST
COUPLE NIGHTS UNDER THE HIGHER DEW POINT AIR...DEWPOINTS IN THE
LOW TO MID 30S SEEMS TO BE ENOUGH FOR DEVELOPMENT. THIS MAY DELAY
THE TIMING OF EROSION OF THE LOW LEVEL MOISTURE AND STRATUS DECK
THURSDAY MORNING. BY MIDDAY THURSDAY 500MB UPPER WAVE AND WILL BE
CENTERED OVER THE FAR EASTERN FA WITH NW SFC WINDS AND SOMEWHAT
DRIER AIR...ALTHOUGH MIXING STILL NOT IMPRESSIVE IN THE
LEAST...SHOULD SEE CLOUDS BEGINNING TO SCATTER OUT. WILL GO WITH
HIGHS IN THE LOW TO MID 40S.
THURSDAY NIGHT INTO FRIDAY PRESSURE GRADIENT INCREASES WITH
AN INCREASE IN CLOUDS AS THE NEXT CLIPPER SYSTEM APPROACHES.
CLOUDS AND INCREASED MIXING WILL KEEP LOW TEMPS UP INTO THE LOW
30S.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 345 PM CDT WED OCT 30 2013
THE NEXT SHORTWAVE WILL DROP INTO THE REGION ALONG THE 500MB NW
FLOW FRIDAY. THERMAL COLUMN REMAINS WARM ENOUGH TO SUPPORT ALL
LIQUID PTYPE WITH ANY SHOWER ACTIVITY THAT DOES DEVELOP ALONG
FROPA OR UNDER COLD POOL ALOFT. BEHIND FROPA WINDS WILL BE STRONG
AS 30KTS OR SO IS AVAILABLE TO MIX DOWN FROM 850MB FRIDAY AFTERNOON.
CYCLONIC FLOW MAY KEEP CLOUDS OVER THE AREA FRIDAY NIGHT INTO
SATURDAY AS SFC HIGH AND UPPER TROUGH SLIDE EAST WITH RETURN
SOUTHERLY SFC FLOW DEVELOPING SATURDAY AFTERNOON.
SUNDAY TO WEDNESDAY...SFC LOW WILL GO JUST NORTH OF THE
INTERNATIONAL BORDER GIVING SOME CHANCE FOR MOSTLY LIQUID PRECIP
ALONG THE NRN TIER OF COUNTIES. COOLER AIR WILL MOVE IN BEHIND FOR
A POSSIBLE RA/SN MIX OF LIGHT PRECIP SUN NIGHT IN THE FAR NORTH.
NOT MUCH WRAP AROUND PRECIP WITH THIS EVENT AS SFC-UPPER LOW REMAIN
FAR ENOUGH NORTH. 12Z EURO CAME IN A BIT FARTHER SOUTH HOWEVER SO
WILL NEED TO WATCH FOR ANY SOUTHWARD ADJUSTMENT WHICH WOULD MEAN
HIGHER POPS IN THE NORTH. OTHERWISE A 500 MB SHORT WAVE WILL DROP
INTO THE 4 CORNERS REGION AND THEN MOVE NORTHEAST. MODELS DIFFER
ON TRACK AND TIMING BUT OVERALL SHOW SYSTEM COMING OUT AS A
POSITIVE TILT AND FAIRLY WEAK LOW MONDAY INTO EARLY TUESDAY. SOME
LIGHT MIXED PRECIP MON- TUE WITH THIS...WITH TRACK OF SYSTEM
INDICATING BRUNT MAY BE TO OUR EAST AND SOUTH. 12Z GFS HOWEVER IS
A BIT STRONGER AND COLDER AND WOULD SIGNAL MORE WINTRY PRECIP THAN
THE ALL BLEND TOOL USED FOR THE FORECAST WOULD INDICATE. HIGH
PRESSURE BUILDS IN BY WED WITH A SEASONABLY CHILLY AIRMASS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 637 PM CDT WED OCT 30 2013
IFR/MVFR CIGS ACROSS THE REGION WILL ONLY SLOWLY CLEAR FROM WEST
TO EAST THROUGH THE PERIOD. USED THE RAP GUIDANCE FOR HEIGHT AND
TIMING PURPOSES AS IT APPEARS TO HAVE A GOOD HANDLE ON THE CURRENT
SITUATION.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...DENSE FOG ADVISORY UNTIL 10 AM CDT THURSDAY FOR MNZ015>017-
022>024-027-028-030>032-040.
&&
$$
UPDATE...TG
SHORT TERM...JK
LONG TERM...JK/RIDDLE
AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
637 PM CDT WED OCT 30 2013
.UPDATE...
ISSUED AT 637 PM CDT WED OCT 30 2013
CLOUDS REMAIN ACROSS THE ENTIRE FA...AND WILL DELAY THE PROGRESS
OF CLEARING FROM WEST TO EAST. WITH THIS...WILL KEEP TEMPERATURES
NEARLY STEADY UNTIL CLEARING IS EXPECTED. THE MAIN CHALLENGE
OVERNIGHT WILL BE POTENTIAL DENSE FOG ACROSS WEST CENTRAL
MINNESOTA. THE 20Z RAP IS INDICATING THIS POSSIBILITY. VISIBILITY
IS ALREADY 1SM-2SM HERE...WITH 1/4SM VSBY JUST TO THE SOUTH. WINDS
ARE EXPECTED TO REMAIN NEARLY CALM MUCH OF THE NIGHT...SO DENSE
FOG AFTER SUNSET APPEARS POSSIBLE (ALTHOUGH CONFIDENCE NOT ENOUGH
AT THIS POINT FOR AN ADVISORY).
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 345 PM CDT WED OCT 30 2013
CHALLENGES FOR THE FORECAST INCLUDE TEMPS AND ENDING TIME OF THE
DRIZZLE/LIGHT RAIN OVERNIGHT INTO TOMORROW MORNING. MODELS IN FAIR
AGREEMENT WITH THIS PERIOD AND WILL USE A BLEND FOR THE FORECAST.
THIS EVENING WILL CONTINUE TO SEE VERY WEAK LOW LEVEL MOISTURE/TEMP
ADVECTION IN THE SE THIRD OF THE FA. TOWARD 06Z 850MB WINDS
INCREASE AND BECOME S TO SWERLY. ALSO SFC WINDS WILL TURN TO THE
WEST ALTHOUGH REMAIN LIGHT. DID ADD A MENTION OF PATCHY FOG
OVERNIGHT WITH SATURATED AIRMASS AND THE FOG OCCURRENCE THE PAST
COUPLE NIGHTS UNDER THE HIGHER DEW POINT AIR...DEWPOINTS IN THE
LOW TO MID 30S SEEMS TO BE ENOUGH FOR DEVELOPMENT. THIS MAY DELAY
THE TIMING OF EROSION OF THE LOW LEVEL MOISTURE AND STRATUS DECK
THURSDAY MORNING. BY MIDDAY THURSDAY 500MB UPPER WAVE AND WILL BE
CENTERED OVER THE FAR EASTERN FA WITH NW SFC WINDS AND SOMEWHAT
DRIER AIR...ALTHOUGH MIXING STILL NOT IMPRESSIVE IN THE
LEAST...SHOULD SEE CLOUDS BEGINNING TO SCATTER OUT. WILL GO WITH
HIGHS IN THE LOW TO MID 40S.
THURSDAY NIGHT INTO FRIDAY PRESSURE GRADIENT INCREASES WITH
AN INCREASE IN CLOUDS AS THE NEXT CLIPPER SYSTEM APPROACHES.
CLOUDS AND INCREASED MIXING WILL KEEP LOW TEMPS UP INTO THE LOW
30S.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 345 PM CDT WED OCT 30 2013
THE NEXT SHORTWAVE WILL DROP INTO THE REGION ALONG THE 500MB NW
FLOW FRIDAY. THERMAL COLUMN REMAINS WARM ENOUGH TO SUPPORT ALL
LIQUID PTYPE WITH ANY SHOWER ACTIVITY THAT DOES DEVELOP ALONG
FROPA OR UNDER COLD POOL ALOFT. BEHIND FROPA WINDS WILL BE STRONG
AS 30KTS OR SO IS AVAILABLE TO MIX DOWN FROM 850MB FRIDAY AFTERNOON.
CYCLONIC FLOW MAY KEEP CLOUDS OVER THE AREA FRIDAY NIGHT INTO
SATURDAY AS SFC HIGH AND UPPER TROUGH SLIDE EAST WITH RETURN
SOUTHERLY SFC FLOW DEVELOPING SATURDAY AFTERNOON.
SUNDAY TO WEDNESDAY...SFC LOW WILL GO JUST NORTH OF THE
INTERNATIONAL BORDER GIVING SOME CHANCE FOR MOSTLY LIQUID PRECIP
ALONG THE NRN TIER OF COUNTIES. COOLER AIR WILL MOVE IN BEHIND FOR
A POSSIBLE RA/SN MIX OF LIGHT PRECIP SUN NIGHT IN THE FAR NORTH.
NOT MUCH WRAP AROUND PRECIP WITH THIS EVENT AS SFC-UPPER LOW REMAIN
FAR ENOUGH NORTH. 12Z EURO CAME IN A BIT FARTHER SOUTH HOWEVER SO
WILL NEED TO WATCH FOR ANY SOUTHWARD ADJUSTMENT WHICH WOULD MEAN
HIGHER POPS IN THE NORTH. OTHERWISE A 500 MB SHORT WAVE WILL DROP
INTO THE 4 CORNERS REGION AND THEN MOVE NORTHEAST. MODELS DIFFER
ON TRACK AND TIMING BUT OVERALL SHOW SYSTEM COMING OUT AS A
POSITIVE TILT AND FAIRLY WEAK LOW MONDAY INTO EARLY TUESDAY. SOME
LIGHT MIXED PRECIP MON- TUE WITH THIS...WITH TRACK OF SYSTEM
INDICATING BRUNT MAY BE TO OUR EAST AND SOUTH. 12Z GFS HOWEVER IS
A BIT STRONGER AND COLDER AND WOULD SIGNAL MORE WINTRY PRECIP THAN
THE ALL BLEND TOOL USED FOR THE FORECAST WOULD INDICATE. HIGH
PRESSURE BUILDS IN BY WED WITH A SEASONABLY CHILLY AIRMASS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 637 PM CDT WED OCT 30 2013
IFR/MVFR CIGS ACROSS THE REGION WILL ONLY SLOWLY CLEAR FROM WEST
TO EAST THROUGH THE PERIOD. USED THE RAP GUIDANCE FOR HEIGHT AND
TIMING PURPOSES AS IT APPEARS TO HAVE A GOOD HANDLE ON THE CURRENT
SITUATION.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...TG
SHORT TERM...JK
LONG TERM...JK/RIDDLE
AVIATION...TG
AREA FORECAST DISCUSSION
NWS BISMARCK ND
124 PM CDT TUE OCT 29 2013
.UPDATE...
ISSUED AT 124 PM CDT TUE OCT 29 2013
HAVE RECEIVED REPORTS OF PATCHY FREEZING DRIZZLE ACROSS PORTIONS
OF THE JAMES RIVER VALLEY SOUTH OF JAMESTOWN EARLY THIS AFTERNOON.
THUS...ADDED THE MENTION OF PATCHY FREEZING DRIZZLE TO THESE
LOCATIONS AND ACROSS THE SOUTHWEST WHERE CEILINGS ARE BELOW 1000
FEET. THE LACK OF ICE CRYSTALS IN THE COLUMN WITH SATURATION
WARMER THAN -10 C AND SURFACE TEMPERATURES IN THE UPPER 20S WILL
CONTINUE FOR THESE LOCATIONS THROUGH THE AFTERNOON...WITH THE
THREAT EXPANDING TO POTENTIALLY IMPACT MOST LOCATIONS SOUTH OF ND
HIGHWAY 200 THROUGH THE NIGHT.
UPDATE ISSUED AT 1017 AM CDT TUE OCT 29 2013
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE. THE BIGGEST
QUESTION WILL BE HOW MUCH STRATUS WILL BE ERODED THROUGH THE
AFTERNOON. THE 14 UTC RAP HOLDS NEARLY THE ENTIRE STRATUS FIELD
THIS MORNING IN PLACE...WHILE THE 12 UTC NAM SUGGESTS SOME
CLEARING NORTH AS THE SURFACE RIDGE AXIS SLOWLY PROPAGATES SOUTH.
WILL CONTINUE TO MONITOR TRENDS...HOWEVER...LEANED CLOSER TO THE
RAP GIVEN WEAK EASTERLY UPSLOPE FLOW.
UPDATE ISSUED AT 641 AM CDT TUE OCT 29 2013
HIGH PRESSURE JUST NORTH OF MINNESOTA AT 6 AM CDT WAS RESPONSIBLE
FOR KEEPING SKIES MOSTLY CLEAR OVER THE NORTH CENTRAL PORTION OF
THE STATE OVERNIGHT. LOWS HERE FELL INTO THE TEENS. SKIES WERE
CLOUDY ACROSS THE REMAINDER OF THE FORECAST AREA. ALTHOUGH LIGHT
SNOW THAT FELL ACROSS THE SOUTHWEST AND FAR SOUTH CENTRAL HAS NOW
DISSIPATED. HAVE UPDATED POPS THIS MORNING...STARTING OUT DRY
ACROSS THE CWA. MESOSCALE MODELS CONTINUE TO INDICATE LIGHT
PRECIPITATION LIFTING NORTH FROM SOUTH DAKOTA DURING THE DAY SO
BROUGHT IN SMALL PRECIPITATION CHANCES ACROSS THE FAR SOUTH DURING
THE MORNING AND KEPT THE CHANCE ACROSS THE SOUTH THIS AFTERNOON.
CLOUDS CONTINUE TO BUILD FROM WEST TO EAST ACROSS THE NORTH...SO
THE MAINLY CLEAR SKIES IN THE NORTH CENTRAL EARLY THIS MORNING
SHOULD CLOUD OVER IN THE NEXT FEW HOURS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM CDT TUE OCT 29 2013
FOCUS OF THE SHORT TERM INCLUDES ANTICIPATED DIMINISHING SNOWFALL
THIS MORNING...THEN PRECIPITATION CHANCES AND PRECIP TYPE THIS
AFTERNOON AND TONIGHT.
AT 3 AM CDT...THE UPPER LEVEL LOW REMAINED OVER THE ROCKIES NEAR
NEVADA/IDAHO WITH SOUTHWEST FLOW ALOFT ACROSS THE EASTERN
ROCKIES...THE FRONT RANGE...AND INTO THE DAKOTAS. AT THE
SURFACE...COLD HIGH PRESSURE WAS CENTERED AT THE BORDER OF
MANITOBA/NORTH DAKOTA/MINNESOTA...WITH LOW PRESSURE OVER
COLORADO/WYOMING. THIS WAS RESULTING IN MAINLY CLEAR SKIES OVER THE
NORTHEASTERN HALF OF NORTH DAKOTA...AND CLOUDS OVER THE SOUTHWEST
HALF. LIGHT SNOW FROM ISENTROPIC LIFT/OVERRUNNING PRECIPITATION FROM
EASTERN MONTANA ACROSS WESTERN AND SOUTH CENTRAL NORTH DAKOTA INTO
NORTHERN SOUTH DAKOTA APPEARED TO BE DECREASING IN INTENSITY AND
COVERAGE OVER THE PAST COUPLE OF HOURS...EXCEPT FOR AN ENHANCED AREA
OF LIGHT SNOW OVER NORTH CENTRAL/NORTHEASTERN SOUTH DAKOTA THAT WAS
MOVING NORTHEASTWARD INTO THE JAMES RIVER VALLEY.
THE HRRR 3KM REFLECTIVITY HAS A GOOD HANDLE ON CURRENT RADAR RETURNS
AND WILL FOLLOW THIS TREND IN THAT MODEL FOR THE MORNING HOURS. THE
HRRR DIMINISHES THE SNOWFALL OVER WESTERN NORTH DAKOTA TO NOTHING
AFTER DAYBREAK/12Z. THE MODEL INDICATES SOME CHANCES OF
PRECIPITATION IN PORTIONS OF SOUTH CENTRAL/SOUTHEASTERN NORTH DAKOTA
DURING THE MORNING HOURS. FEEL CONFIDENT THAT BY 6 AM MDT THE
ADVISORY SHOULD BE ALLOWED TO EXPIRE. WILL KEEP SMALL CHANCES OF
PRECIPITATION ACROSS THE FAR SOUTHERN TIER OF COUNTIES THIS MORNING.
FOR THIS AFTERNOON...THE MODELS DEPICT THE UPPER LOW MOVING
NORTHEAST TO WYOMING AND CONTINUED UPPER LEVEL ENERGY IMPULSES
MOVING NORTHEASTWARD TOWARDS NORTH DAKOTA. THUS THE MODELS WERE
KEEPING PRECIPITATION VERY CLOSE TO THE ND BORDER IN SOUTH
DAKOTA...AND WILL KEEP SMALL CHANCE MENTIONS OF LIGHT SNOW OR LIGHT
RAIN. HIGH TEMPERATURES EXPECTED TO REACH ONLY INTO THE 30S...BUT
WITH WARM ADVECTION ALOFT BRINGING A CHANCE OF RAIN/SNOW TO THE FAR
SOUTH.
FOR TONIGHT...THE UPPER LOW REMAINS OVER WYOMING WITH CONTINUED
ENERGY IMPULSES MOVING NORTHWARD ACROSS THE DAKOTAS. WARM ADVECTION
ALOFT CONTINUES WITH SURFACE TEMPERATURES DROPPING BACK INTO THE
UPPER 20S. TEMPERATURE PROFILES FROM BUFKIT SOUNDINGS STILL SUPPORT
FREEZING RAIN. THUS WILL CONTINUE THE CHANCES OF FREEZING RAIN
ACROSS THE SOUTHERN TIER OF COUNTIES AS HAS BEEN ANTICIPATED FOR THE
PAST FEW DAYS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 329 AM CDT TUE OCT 29 2013
MAIN FORECAST PROBLEM IN THE EXTENDED PERIOD WILL BE PRECIPITATION
CHANCES AND TYPE WEDNESDAY AND WEDNESDAY NIGHT AS AN UPPER LEVEL LOW
MOVES THROUGH THE LOCAL AREA. MODELS ARE IN REASONABLE AGREEMENT AND
UTILIZED A MODEL BLEND WITH PERSISTENCE FOR FORECAST ELEMENTS.
THE UPPER LEVEL LOW TRACKING ACROSS THE NORTHERN ROCKIES MOVES INTO
THE NORTHERN PLAINS WEDNESDAY. THE MAIN SURFACE LOW REMAINS OVER THE
CENTRAL PLAINS BUT WARM ADVECTION LIFTS FROM THE PLAINS INTO THE
CENTRAL AND EASTERN DAKOTAS ON WEDNESDAY WITH THE GFS/EC AND GLOBAL
GEM ALL PRODUCING QPF OVER OUR FAR SOUTH CENTRAL AND SOUTHEAST CWA.
WITH SURFACE TEMPERATURES HOVERING AROUND FREEZING AND MAX
TEMPERATURES ALOFT GENERALLY 2-4 DEGREES CELSIUS...THERE WILL BE A
THREAT OF FREEZING RAIN ALONG THE SOUTH DAKOTA BORDER WEDNESDAY
MORNING. AS TEMPERATURES RISE INTO THE UPPER 30S TO LOWER 40S
WEDNESDAY AFTERNOON THE PRECIPITATION IS EXPECTED TO BE ALL RAIN. BY
WEDNESDAY EVENING THE UPPER LOW MOVES EAST AND COLDER AIR FILTERS
INTO THE REGION. BY THIS TIME ANY LINGERING PRECIPITATION IS
EXPECTED TO BE MAINLY OVER THE JAMES RIVER VALLEY...AND AS
TEMPERATURES COOL DURING THE EVENING WE COULD AGAIN SEE A MIXED BAG
OF LIGHT RAIN/FREEZING RAIN OR SNOW BEFORE THE PRECIPITATION ENDS.
WILL NEED TO MONITOR FOR POSSIBLE FREEZING RAIN HIGHLIGHTS FAR SOUTH
CENTRAL AND SOUTHEAST...BUT AT THIS TIME THE GREATEST POTENTIAL FOR
ACCUMULATING PRECIPITATION APPEARS TO BE WEDNESDAY AFTERNOON WHEN
TEMPERATURES WILL BE WARM ENOUGH THAT RAIN WILL BE THE PREDOMINANT
PRECIPITATION TYPE.
NORTHWEST FLOW DEVELOPS THURSDAY INTO FRIDAY. EMBEDDED IMPULSES IN A
STRONG NORTHWEST UPPER FLOW COULD BRING A RAIN OR SNOW SHOWER TO THE
NORTH AND EAST ON FRIDAY...WITH BREEZY NORTHWEST WINDS EXPECTED
ACROSS THE AREA. HIGH TEMPERATURES SHOULD REMAIN IN THE 40S.
THE NEXT SYSTEM COMING OFF THE PACIFIC LIFTS INTO SOUTHERN CANADA
OVER THE WEEKEND. THIS WILL INDUCE A SOUTHEAST FLOW ACROSS THE AREA
LATE SATURDAY THROUGH SUNDAY WITH HIGH TEMPERATURES MAINLY IN THE
MID TO UPPER 40S AND POSSIBLY SOME 50S IN THE WEST. A COLD FRONT
MOVES THROUGH ON MONDAY BRINGING US BACK DOWN INTO THE UPPER 30S AND
40S. HAVE STUCK WITH PERSISTENCE AND KEPT A SLIGHT CHANCE OF
PRECIPITATION ACROSS THE NORTH ON SUNDAY AND MONDAY. ALTHOUGH LATEST
GUIDANCE IS SUGGESTING THAT THE LOW OVER SOUTHERN CANADA MAY BE FAR
ENOUGH NORTH THAT WE WILL REMAIN IN THE DRY SECTOR...ESPECIALLY ON
SUNDAY...WITH MAYBE A FEW COLD ADVECTION RAIN OR SNOW SHOWERS ON
MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 124 PM CDT TUE OCT 29 2013
IFR CONDITIONS IN STRATUS AND FREEZING DRIZZLE WILL CONTINUE AT
KDIK THIS AFTERNOON THROUGH TONIGHT. KBIS AND KJMS ARE EXPECTED
TO FALL TO IFR IN STRATUS AND FREEZING DRIZZLE AS WELL IN THE
06-09 UTC TIME FRAME TONIGHT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...JV
LONG TERM...TWH
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1019 AM CDT TUE OCT 29 2013
.UPDATE...
ISSUED AT 1017 AM CDT TUE OCT 29 2013
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE. THE BIGGEST
QUESTION WILL BE HOW MUCH STRATUS WILL BE ERODED THROUGH THE
AFTERNOON. THE 14 UTC RAP HOLDS NEARLY THE ENTIRE STRATUS FIELD
THIS MORNING IN PLACE...WHILE THE 12 UTC NAM SUGGESTS SOME
CLEARING NORTH AS THE SURFACE RIDGE AXIS SLOWLY PROPAGATES SOUTH.
WILL CONTINUE TO MONITOR TRENDS...HOWEVER...LEANED CLOSER TO THE
RAP GIVEN WEAK EASTERLY UPSLOPE FLOW.
UPDATE ISSUED AT 641 AM CDT TUE OCT 29 2013
HIGH PRESSURE JUST NORTH OF MINNESOTA AT 6 AM CDT WAS RESPONSIBLE
FOR KEEPING SKIES MOSTLY CLEAR OVER THE NORTH CENTRAL PORTION OF
THE STATE OVERNIGHT. LOWS HERE FELL INTO THE TEENS. SKIES WERE
CLOUDY ACROSS THE REMAINDER OF THE FORECAST AREA. ALTHOUGH LIGHT
SNOW THAT FELL ACROSS THE SOUTHWEST AND FAR SOUTH CENTRAL HAS NOW
DISSIPATED. HAVE UPDATED POPS THIS MORNING...STARTING OUT DRY
ACROSS THE CWA. MESOSCALE MODELS CONTINUE TO INDICATE LIGHT
PRECIPITATION LIFTING NORTH FROM SOUTH DAKOTA DURING THE DAY SO
BROUGHT IN SMALL PRECIPITATION CHANCES ACROSS THE FAR SOUTH DURING
THE MORNING AND KEPT THE CHANCE ACROSS THE SOUTH THIS AFTERNOON.
CLOUDS CONTINUE TO BUILD FROM WEST TO EAST ACROSS THE NORTH...SO
THE MAINLY CLEAR SKIES IN THE NORTH CENTRAL EARLY THIS MORNING
SHOULD CLOUD OVER IN THE NEXT FEW HOURS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM CDT TUE OCT 29 2013
FOCUS OF THE SHORT TERM INCLUDES ANTICIPATED DIMINISHING SNOWFALL
THIS MORNING...THEN PRECIPITATION CHANCES AND PRECIP TYPE THIS
AFTERNOON AND TONIGHT.
AT 3 AM CDT...THE UPPER LEVEL LOW REMAINED OVER THE ROCKIES NEAR
NEVADA/IDAHO WITH SOUTHWEST FLOW ALOFT ACROSS THE EASTERN
ROCKIES...THE FRONT RANGE...AND INTO THE DAKOTAS. AT THE
SURFACE...COLD HIGH PRESSURE WAS CENTERED AT THE BORDER OF
MANITOBA/NORTH DAKOTA/MINNESOTA...WITH LOW PRESSURE OVER
COLORADO/WYOMING. THIS WAS RESULTING IN MAINLY CLEAR SKIES OVER THE
NORTHEASTERN HALF OF NORTH DAKOTA...AND CLOUDS OVER THE SOUTHWEST
HALF. LIGHT SNOW FROM ISENTROPIC LIFT/OVERRUNNING PRECIPITATION FROM
EASTERN MONTANA ACROSS WESTERN AND SOUTH CENTRAL NORTH DAKOTA INTO
NORTHERN SOUTH DAKOTA APPEARED TO BE DECREASING IN INTENSITY AND
COVERAGE OVER THE PAST COUPLE OF HOURS...EXCEPT FOR AN ENHANCED AREA
OF LIGHT SNOW OVER NORTH CENTRAL/NORTHEASTERN SOUTH DAKOTA THAT WAS
MOVING NORTHEASTWARD INTO THE JAMES RIVER VALLEY.
THE HRRR 3KM REFLECTIVITY HAS A GOOD HANDLE ON CURRENT RADAR RETURNS
AND WILL FOLLOW THIS TREND IN THAT MODEL FOR THE MORNING HOURS. THE
HRRR DIMINISHES THE SNOWFALL OVER WESTERN NORTH DAKOTA TO NOTHING
AFTER DAYBREAK/12Z. THE MODEL INDICATES SOME CHANCES OF
PRECIPITATION IN PORTIONS OF SOUTH CENTRAL/SOUTHEASTERN NORTH DAKOTA
DURING THE MORNING HOURS. FEEL CONFIDENT THAT BY 6 AM MDT THE
ADVISORY SHOULD BE ALLOWED TO EXPIRE. WILL KEEP SMALL CHANCES OF
PRECIPITATION ACROSS THE FAR SOUTHERN TIER OF COUNTIES THIS MORNING.
FOR THIS AFTERNOON...THE MODELS DEPICT THE UPPER LOW MOVING
NORTHEAST TO WYOMING AND CONTINUED UPPER LEVEL ENERGY IMPULSES
MOVING NORTHEASTWARD TOWARDS NORTH DAKOTA. THUS THE MODELS WERE
KEEPING PRECIPITATION VERY CLOSE TO THE ND BORDER IN SOUTH
DAKOTA...AND WILL KEEP SMALL CHANCE MENTIONS OF LIGHT SNOW OR LIGHT
RAIN. HIGH TEMPERATURES EXPECTED TO REACH ONLY INTO THE 30S...BUT
WITH WARM ADVECTION ALOFT BRINGING A CHANCE OF RAIN/SNOW TO THE FAR
SOUTH.
FOR TONIGHT...THE UPPER LOW REMAINS OVER WYOMING WITH CONTINUED
ENERGY IMPULSES MOVING NORTHWARD ACROSS THE DAKOTAS. WARM ADVECTION
ALOFT CONTINUES WITH SURFACE TEMPERATURES DROPPING BACK INTO THE
UPPER 20S. TEMPERATURE PROFILES FROM BUFKIT SOUNDINGS STILL SUPPORT
FREEZING RAIN. THUS WILL CONTINUE THE CHANCES OF FREEZING RAIN
ACROSS THE SOUTHERN TIER OF COUNTIES AS HAS BEEN ANTICIPATED FOR THE
PAST FEW DAYS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 329 AM CDT TUE OCT 29 2013
MAIN FORECAST PROBLEM IN THE EXTENDED PERIOD WILL BE PRECIPITATION
CHANCES AND TYPE WEDNESDAY AND WEDNESDAY NIGHT AS AN UPPER LEVEL LOW
MOVES THROUGH THE LOCAL AREA. MODELS ARE IN REASONABLE AGREEMENT AND
UTILIZED A MODEL BLEND WITH PERSISTENCE FOR FORECAST ELEMENTS.
THE UPPER LEVEL LOW TRACKING ACROSS THE NORTHERN ROCKIES MOVES INTO
THE NORTHERN PLAINS WEDNESDAY. THE MAIN SURFACE LOW REMAINS OVER THE
CENTRAL PLAINS BUT WARM ADVECTION LIFTS FROM THE PLAINS INTO THE
CENTRAL AND EASTERN DAKOTAS ON WEDNESDAY WITH THE GFS/EC AND GLOBAL
GEM ALL PRODUCING QPF OVER OUR FAR SOUTH CENTRAL AND SOUTHEAST CWA.
WITH SURFACE TEMPERATURES HOVERING AROUND FREEZING AND MAX
TEMPERATURES ALOFT GENERALLY 2-4 DEGREES CELSIUS...THERE WILL BE A
THREAT OF FREEZING RAIN ALONG THE SOUTH DAKOTA BORDER WEDNESDAY
MORNING. AS TEMPERATURES RISE INTO THE UPPER 30S TO LOWER 40S
WEDNESDAY AFTERNOON THE PRECIPITATION IS EXPECTED TO BE ALL RAIN. BY
WEDNESDAY EVENING THE UPPER LOW MOVES EAST AND COLDER AIR FILTERS
INTO THE REGION. BY THIS TIME ANY LINGERING PRECIPITATION IS
EXPECTED TO BE MAINLY OVER THE JAMES RIVER VALLEY...AND AS
TEMPERATURES COOL DURING THE EVENING WE COULD AGAIN SEE A MIXED BAG
OF LIGHT RAIN/FREEZING RAIN OR SNOW BEFORE THE PRECIPITATION ENDS.
WILL NEED TO MONITOR FOR POSSIBLE FREEZING RAIN HIGHLIGHTS FAR SOUTH
CENTRAL AND SOUTHEAST...BUT AT THIS TIME THE GREATEST POTENTIAL FOR
ACCUMULATING PRECIPITATION APPEARS TO BE WEDNESDAY AFTERNOON WHEN
TEMPERATURES WILL BE WARM ENOUGH THAT RAIN WILL BE THE PREDOMINANT
PRECIPITATION TYPE.
NORTHWEST FLOW DEVELOPS THURSDAY INTO FRIDAY. EMBEDDED IMPULSES IN A
STRONG NORTHWEST UPPER FLOW COULD BRING A RAIN OR SNOW SHOWER TO THE
NORTH AND EAST ON FRIDAY...WITH BREEZY NORTHWEST WINDS EXPECTED
ACROSS THE AREA. HIGH TEMPERATURES SHOULD REMAIN IN THE 40S.
THE NEXT SYSTEM COMING OFF THE PACIFIC LIFTS INTO SOUTHERN CANADA
OVER THE WEEKEND. THIS WILL INDUCE A SOUTHEAST FLOW ACROSS THE AREA
LATE SATURDAY THROUGH SUNDAY WITH HIGH TEMPERATURES MAINLY IN THE
MID TO UPPER 40S AND POSSIBLY SOME 50S IN THE WEST. A COLD FRONT
MOVES THROUGH ON MONDAY BRINGING US BACK DOWN INTO THE UPPER 30S AND
40S. HAVE STUCK WITH PERSISTENCE AND KEPT A SLIGHT CHANCE OF
PRECIPITATION ACROSS THE NORTH ON SUNDAY AND MONDAY. ALTHOUGH LATEST
GUIDANCE IS SUGGESTING THAT THE LOW OVER SOUTHERN CANADA MAY BE FAR
ENOUGH NORTH THAT WE WILL REMAIN IN THE DRY SECTOR...ESPECIALLY ON
SUNDAY...WITH MAYBE A FEW COLD ADVECTION RAIN OR SNOW SHOWERS ON
MONDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 1017 AM CDT TUE OCT 29 2013
WIDESPREAD STRATUS ACROSS WESTERN AND CENTRAL NORTH DAKOTA THIS
MORNING WILL HOLD IN PLACE FOR MOST TAF SITES TODAY. IFR
CONDITIONS WILL PERSIST FOR THE MAJORITY OF THE 12 UTC TAF PERIOD
FOR KDIK. OTHERWISE...VFR STRATUS WILL LOWER TO IFR TONIGHT AT
KJMS/KBIS WITH FREEZING DRIZZLE POSSIBLE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...JV
LONG TERM...TWH
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
641 AM CDT TUE OCT 29 2013
.UPDATE...
ISSUED AT 641 AM CDT TUE OCT 29 2013
HIGH PRESSURE JUST NORTH OF MINNESOTA AT 6 AM CDT WAS RESPONSIBLE
FOR KEEPING SKIES MOSTLY CLEAR OVER THE NORTH CENTRAL PORTION OF
THE STATE OVERNIGHT. LOWS HERE FELL INTO THE TEENS. SKIES WERE
CLOUDY ACROSS THE REMAINDER OF THE FORECAST AREA. ALTHOUGH LIGHT
SNOW THAT FELL ACROSS THE SOUTHWEST AND FAR SOUTH CENTRAL HAS NOW
DISSIPATED. HAVE UPDATED POPS THIS MORNING...STARTING OUT DRY
ACROSS THE CWA. MESOSCALE MODELS CONTINUE TO INDICATE LIGHT
PRECIPITATION LIFTING NORTH FROM SOUTH DAKOTA DURING THE DAY SO
BROUGHT IN SMALL PRECIPITATION CHANCES ACROSS THE FAR SOUTH DURING
THE MORNING AND KEPT THE CHANCE ACROSS THE SOUTH THIS AFTERNOON.
CLOUDS CONTINUE TO BUILD FROM WEST TO EAST ACROSS THE NORTH...SO
THE MAINLY CLEAR SKIES IN THE NORTH CENTRAL EARLY THIS MORNING
SHOULD CLOUD OVER IN THE NEXT FEW HOURS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM CDT TUE OCT 29 2013
FOCUS OF THE SHORT TERM INCLUDES ANTICIPATED DIMINISHING SNOWFALL
THIS MORNING...THEN PRECIPITATION CHANCES AND PRECIP TYPE THIS
AFTERNOON AND TONIGHT.
AT 3 AM CDT...THE UPPER LEVEL LOW REMAINED OVER THE ROCKIES NEAR
NEVADA/IDAHO WITH SOUTHWEST FLOW ALOFT ACROSS THE EASTERN
ROCKIES...THE FRONT RANGE...AND INTO THE DAKOTAS. AT THE
SURFACE...COLD HIGH PRESSURE WAS CENTERED AT THE BORDER OF
MANITOBA/NORTH DAKOTA/MINNESOTA...WITH LOW PRESSURE OVER
COLORADO/WYOMING. THIS WAS RESULTING IN MAINLY CLEAR SKIES OVER THE
NORTHEASTERN HALF OF NORTH DAKOTA...AND CLOUDS OVER THE SOUTHWEST
HALF. LIGHT SNOW FROM ISENTROPIC LIFT/OVERRUNNING PRECIPITATION FROM
EASTERN MONTANA ACROSS WESTERN AND SOUTH CENTRAL NORTH DAKOTA INTO
NORTHERN SOUTH DAKOTA APPEARED TO BE DECREASING IN INTENSITY AND
COVERAGE OVER THE PAST COUPLE OF HOURS...EXCEPT FOR AN ENHANCED AREA
OF LIGHT SNOW OVER NORTH CENTRAL/NORTHEASTERN SOUTH DAKOTA THAT WAS
MOVING NORTHEASTWARD INTO THE JAMES RIVER VALLEY.
THE HRRR 3KM REFLECTIVITY HAS A GOOD HANDLE ON CURRENT RADAR RETURNS
AND WILL FOLLOW THIS TREND IN THAT MODEL FOR THE MORNING HOURS. THE
HRRR DIMINISHES THE SNOWFALL OVER WESTERN NORTH DAKOTA TO NOTHING
AFTER DAYBREAK/12Z. THE MODEL INDICATES SOME CHANCES OF
PRECIPITATION IN PORTIONS OF SOUTH CENTRAL/SOUTHEASTERN NORTH DAKOTA
DURING THE MORNING HOURS. FEEL CONFIDENT THAT BY 6 AM MDT THE
ADVISORY SHOULD BE ALLOWED TO EXPIRE. WILL KEEP SMALL CHANCES OF
PRECIPITATION ACROSS THE FAR SOUTHERN TIER OF COUNTIES THIS MORNING.
FOR THIS AFTERNOON...THE MODELS DEPICT THE UPPER LOW MOVING
NORTHEAST TO WYOMING AND CONTINUED UPPER LEVEL ENERGY IMPULSES
MOVING NORTHEASTWARD TOWARDS NORTH DAKOTA. THUS THE MODELS WERE
KEEPING PRECIPITATION VERY CLOSE TO THE ND BORDER IN SOUTH
DAKOTA...AND WILL KEEP SMALL CHANCE MENTIONS OF LIGHT SNOW OR LIGHT
RAIN. HIGH TEMPERATURES EXPECTED TO REACH ONLY INTO THE 30S...BUT
WITH WARM ADVECTION ALOFT BRINGING A CHANCE OF RAIN/SNOW TO THE FAR
SOUTH.
FOR TONIGHT...THE UPPER LOW REMAINS OVER WYOMING WITH CONTINUED
ENERGY IMPULSES MOVING NORTHWARD ACROSS THE DAKOTAS. WARM ADVECTION
ALOFT CONTINUES WITH SURFACE TEMPERATURES DROPPING BACK INTO THE
UPPER 20S. TEMPERATURE PROFILES FROM BUFKIT SOUNDINGS STILL SUPPORT
FREEZING RAIN. THUS WILL CONTINUE THE CHANCES OF FREEZING RAIN
ACROSS THE SOUTHERN TIER OF COUNTIES AS HAS BEEN ANTICIPATED FOR THE
PAST FEW DAYS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 329 AM CDT TUE OCT 29 2013
MAIN FORECAST PROBLEM IN THE EXTENDED PERIOD WILL BE PRECIPITATION
CHANCES AND TYPE WEDNESDAY AND WEDNESDAY NIGHT AS AN UPPER LEVEL LOW
MOVES THROUGH THE LOCAL AREA. MODELS ARE IN REASONABLE AGREEMENT AND
UTILIZED A MODEL BLEND WITH PERSISTENCE FOR FORECAST ELEMENTS.
THE UPPER LEVEL LOW TRACKING ACROSS THE NORTHERN ROCKIES MOVES INTO
THE NORTHERN PLAINS WEDNESDAY. THE MAIN SURFACE LOW REMAINS OVER THE
CENTRAL PLAINS BUT WARM ADVECTION LIFTS FROM THE PLAINS INTO THE
CENTRAL AND EASTERN DAKOTAS ON WEDNESDAY WITH THE GFS/EC AND GLOBAL
GEM ALL PRODUCING QPF OVER OUR FAR SOUTH CENTRAL AND SOUTHEAST CWA.
WITH SURFACE TEMPERATURES HOVERING AROUND FREEZING AND MAX
TEMPERATURES ALOFT GENERALLY 2-4 DEGREES CELSIUS...THERE WILL BE A
THREAT OF FREEZING RAIN ALONG THE SOUTH DAKOTA BORDER WEDNESDAY
MORNING. AS TEMPERATURES RISE INTO THE UPPER 30S TO LOWER 40S
WEDNESDAY AFTERNOON THE PRECIPITATION IS EXPECTED TO BE ALL RAIN. BY
WEDNESDAY EVENING THE UPPER LOW MOVES EAST AND COLDER AIR FILTERS
INTO THE REGION. BY THIS TIME ANY LINGERING PRECIPITATION IS
EXPECTED TO BE MAINLY OVER THE JAMES RIVER VALLEY...AND AS
TEMPERATURES COOL DURING THE EVENING WE COULD AGAIN SEE A MIXED BAG
OF LIGHT RAIN/FREEZING RAIN OR SNOW BEFORE THE PRECIPITATION ENDS.
WILL NEED TO MONITOR FOR POSSIBLE FREEZING RAIN HIGHLIGHTS FAR SOUTH
CENTRAL AND SOUTHEAST...BUT AT THIS TIME THE GREATEST POTENTIAL FOR
ACCUMULATING PRECIPITATION APPEARS TO BE WEDNESDAY AFTERNOON WHEN
TEMPERATURES WILL BE WARM ENOUGH THAT RAIN WILL BE THE PREDOMINANT
PRECIPITATION TYPE.
NORTHWEST FLOW DEVELOPS THURSDAY INTO FRIDAY. EMBEDDED IMPULSES IN A
STRONG NORTHWEST UPPER FLOW COULD BRING A RAIN OR SNOW SHOWER TO THE
NORTH AND EAST ON FRIDAY...WITH BREEZY NORTHWEST WINDS EXPECTED
ACROSS THE AREA. HIGH TEMPERATURES SHOULD REMAIN IN THE 40S.
THE NEXT SYSTEM COMING OFF THE PACIFIC LIFTS INTO SOUTHERN CANADA
OVER THE WEEKEND. THIS WILL INDUCE A SOUTHEAST FLOW ACROSS THE AREA
LATE SATURDAY THROUGH SUNDAY WITH HIGH TEMPERATURES MAINLY IN THE
MID TO UPPER 40S AND POSSIBLY SOME 50S IN THE WEST. A COLD FRONT
MOVES THROUGH ON MONDAY BRINGING US BACK DOWN INTO THE UPPER 30S AND
40S. HAVE STUCK WITH PERSISTENCE AND KEPT A SLIGHT CHANCE OF
PRECIPITATION ACROSS THE NORTH ON SUNDAY AND MONDAY. ALTHOUGH LATEST
GUIDANCE IS SUGGESTING THAT THE LOW OVER SOUTHERN CANADA MAY BE FAR
ENOUGH NORTH THAT WE WILL REMAIN IN THE DRY SECTOR...ESPECIALLY ON
SUNDAY...WITH MAYBE A FEW COLD ADVECTION RAIN OR SNOW SHOWERS ON
MONDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 641 AM CDT TUE OCT 29 2013
AT 630 AM CDT...A LARGE SURFACE HIGH PRESSURE WAS CENTERED OVER THE
BORDERS OF MANITOBA/NORTH DAKOTA/MINNESOTA...WITH LOW PRESSURE OVER
COLORADO/WYOMING. THESE 2 FEATURES ARE FORECAST TO MOVE EAST TODAY.
MVFR CIGS WERE WEST OF KISN IN NORTHEASTERN MONTANA...THUS PUT A
TEMPO GROUP FOR A FEW HOURS THIS MORNING AT KISN/KDIK. OTHERWISE VFR
AT KBIS/KJMS/KMOT.
LATER THIS TUESDAY EVENING A LARGE AREA OF LOW/MID CLOUDINESS SHOULD
MOVE NORTHWARD BRINGING MVFR CIGS TO SOUTHERN TAF SITES OF
KDIK/KBIS/KJMS AFT 02Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...JV
LONG TERM...TWH
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
328 AM CDT TUE OCT 29 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM CDT TUE OCT 29 2013
FOCUS OF THE SHORT TERM INCLUDES ANTICIPATED DIMINISHING SNOWFALL
THIS MORNING...THEN PRECIPITATION CHANCES AND PRECIP TYPE THIS
AFTERNOON AND TONIGHT.
AT 3 AM CDT...THE UPPER LEVEL LOW REMAINED OVER THE ROCKIES NEAR
NEVADA/IDAHO WITH SOUTHWEST FLOW ALOFT ACROSS THE EASTERN
ROCKIES...THE FRONT RANGE...AND INTO THE DAKOTAS. AT THE
SURFACE...COLD HIGH PRESSURE WAS CENTERED AT THE BORDER OF
MANITOBA/NORTH DAKOTA/MINNESOTA...WITH LOW PRESSURE OVER
COLORADO/WYOMING. THIS WAS RESULTING IN MAINLY CLEAR SKIES OVER THE
NORTHEASTERN HALF OF NORTH DAKOTA...AND CLOUDS OVER THE SOUTHWEST
HALF. LIGHT SNOW FROM ISENTROPIC LIFT/OVERRUNNING PRECIPITATION FROM
EASTERN MONTANA ACROSS WESTERN AND SOUTH CENTRAL NORTH DAKOTA INTO
NORTHERN SOUTH DAKOTA APPEARED TO BE DECREASING IN INTENSITY AND
COVERAGE OVER THE PAST COUPLE OF HOURS...EXCEPT FOR AN ENHANCED AREA
OF LIGHT SNOW OVER NORTH CENTRAL/NORTHEASTERN SOUTH DAKOTA THAT WAS
MOVING NORTHEASTWARD INTO THE JAMES RIVER VALLEY.
THE HRRR 3KM REFLECTIVITY HAS A GOOD HANDLE ON CURRENT RADAR RETURNS
AND WILL FOLLOW THIS TREND IN THAT MODEL FOR THE MORNING HOURS. THE
HRRR DIMINISHES THE SNOWFALL OVER WESTERN NORTH DAKOTA TO NOTHING
AFTER DAYBREAK/12Z. THE MODEL INDICATES SOME CHANCES OF
PRECIPITATION IN PORTIONS OF SOUTH CENTRAL/SOUTHEASTERN NORTH DAKOTA
DURING THE MORNING HOURS. FEEL CONFIDENT THAT BY 6 AM MDT THE
ADVISORY SHOULD BE ALLOWED TO EXPIRE. WILL KEEP SMALL CHANCES OF
PRECIPITATION ACROSS THE FAR SOUTHERN TIER OF COUNTIES THIS MORNING.
FOR THIS AFTERNOON...THE MODELS DEPICT THE UPPER LOW MOVING
NORTHEAST TO WYOMING AND CONTINUED UPPER LEVEL ENERGY IMPULSES
MOVING NORTHEASTWARD TOWARDS NORTH DAKOTA. THUS THE MODELS WERE
KEEPING PRECIPITATION VERY CLOSE TO THE ND BORDER IN SOUTH
DAKOTA...AND WILL KEEP SMALL CHANCE MENTIONS OF LIGHT SNOW OR LIGHT
RAIN. HIGH TEMPERATURES EXPECTED TO REACH ONLY INTO THE 30S...BUT
WITH WARM ADVECTION ALOFT BRINGING A CHANCE OF RAIN/SNOW TO THE FAR
SOUTH.
FOR TONIGHT...THE UPPER LOW REMAINS OVER WYOMING WITH CONTINUED
ENERGY IMPULSES MOVING NORTHWARD ACROSS THE DAKOTAS. WARM ADVECTION
ALOFT CONTINUES WITH SURFACE TEMPERATURES DROPPING BACK INTO THE
UPPER 20S. TEMPERATURE PROFILES FROM BUFKIT SOUNDINGS STILL SUPPORT
FREEZING RAIN. THUS WILL CONTINUE THE CHANCES OF FREEZING RAIN
ACROSS THE SOUTHERN TIER OF COUNTIES AS HAS BEEN ANTICIPATED FOR THE
PAST FEW DAYS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 329 AM CDT TUE OCT 29 2013
MAIN FORECAST PROBLEM IN THE EXTENDED PERIOD WILL BE PRECIPITATION
CHANCES AND TYPE WEDNESDAY AND WEDNESDAY NIGHT AS AN UPPER LEVEL LOW
MOVES THROUGH THE LOCAL AREA. MODELS ARE IN REASONABLE AGREEMENT AND
UTILIZED A MODEL BLEND WITH PERSISTENCE FOR FORECAST ELEMENTS.
THE UPPER LEVEL LOW TRACKING ACROSS THE NORTHERN ROCKIES MOVES INTO
THE NORTHERN PLAINS WEDNESDAY. THE MAIN SURFACE LOW REMAINS OVER THE
CENTRAL PLAINS BUT WARM ADVECTION LIFTS FROM THE PLAINS INTO THE
CENTRAL AND EASTERN DAKOTAS ON WEDNESDAY WITH THE GFS/EC AND GLOBAL
GEM ALL PRODUCING QPF OVER OUR FAR SOUTH CENTRAL AND SOUTHEAST CWA.
WITH SURFACE TEMPERATURES HOVERING AROUND FREEZING AND MAX
TEMPERATURES ALOFT GENERALLY 2-4 DEGREES CELSIUS...THERE WILL BE A
THREAT OF FREEZING RAIN ALONG THE SOUTH DAKOTA BORDER WEDNESDAY
MORNING. AS TEMPERATURES RISE INTO THE UPPER 30S TO LOWER 40S
WEDNESDAY AFTERNOON THE PRECIPITATION IS EXPECTED TO BE ALL RAIN. BY
WEDNESDAY EVENING THE UPPER LOW MOVES EAST AND COLDER AIR FILTERS
INTO THE REGION. BY THIS TIME ANY LINGERING PRECIPITATION IS
EXPECTED TO BE MAINLY OVER THE JAMES RIVER VALLEY...AND AS
TEMPERATURES COOL DURING THE EVENING WE COULD AGAIN SEE A MIXED BAG
OF LIGHT RAIN/FREEZING RAIN OR SNOW BEFORE THE PRECIPITATION ENDS.
WILL NEED TO MONITOR FOR POSSIBLE FREEZING RAIN HIGHLIGHTS FAR SOUTH
CENTRAL AND SOUTHEAST...BUT AT THIS TIME THE GREATEST POTENTIAL FOR
ACCUMULATING PRECIPITATION APPEARS TO BE WEDNESDAY AFTERNOON WHEN
TEMPERATURES WILL BE WARM ENOUGH THAT RAIN WILL BE THE PREDOMINANT
PRECIPITATION TYPE.
NORTHWEST FLOW DEVELOPS THURSDAY INTO FRIDAY. EMBEDDED IMPULSES IN A
STRONG NORTHWEST UPPER FLOW COULD BRING A RAIN OR SNOW SHOWER TO THE
NORTH AND EAST ON FRIDAY...WITH BREEZY NORTHWEST WINDS EXPECTED
ACROSS THE AREA. HIGH TEMPERATURES SHOULD REMAIN IN THE 40S.
THE NEXT SYSTEM COMING OFF THE PACIFIC LIFTS INTO SOUTHERN CANADA
OVER THE WEEKEND. THIS WILL INDUCE A SOUTHEAST FLOW ACROSS THE AREA
LATE SATURDAY THROUGH SUNDAY WITH HIGH TEMPERATURES MAINLY IN THE
MID TO UPPER 40S AND POSSIBLY SOME 50S IN THE WEST. A COLD FRONT
MOVES THROUGH ON MONDAY BRINGING US BACK DOWN INTO THE UPPER 30S AND
40S. HAVE STUCK WITH PERSISTENCE AND KEPT A SLIGHT CHANCE OF
PRECIPITATION ACROSS THE NORTH ON SUNDAY AND MONDAY. ALTHOUGH LATEST
GUIDANCE IS SUGGESTING THAT THE LOW OVER SOUTHERN CANADA MAY BE FAR
ENOUGH NORTH THAT WE WILL REMAIN IN THE DRY SECTOR...ESPECIALLY ON
SUNDAY...WITH MAYBE A FEW COLD ADVECTION RAIN OR SNOW SHOWERS ON
MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1245 AM CDT TUE OCT 29 2013
HAZARDS TO AVIATION TONIGHT WILL BE MVFR TO IFR CONDITIONS IN SNOW
ACROSS SOUTHWEST NORTH DAKOTA. AT 1230 AM CDT...A LARGE SURFACE HIGH
PRESSURE WAS CENTERED OVER THE BORDERS OF MANITOBA/NORTH
DAKOTA/MINNESOTA...WITH LOW PRESSURE OVER COLORADO/WYOMING. THESE 2
FEATURES ARE FORECAST TO MOVE EAST TONIGHT. THIS WILL SPREAD SNOW
ACROSS THE SOUTHERN HALF OF THE STATE...CONTINUING TO IMPACT KDIK
WITH IFR CONDITIONS TONIGHT. MVFR VSBY AT KDIK SHOULD IMPROVE TO 5SM
BY 09Z AND THOUGH SNOW SHOULD BE ENDING EXPECT FOG WITH MVFR VSBY
UNTIL AROUND 18Z. MVFR IS FORECAST TO CONTINUE IN KISN...DEVELOP
AT KBIS AROUND/AFTER 08Z AND AT KJMS AFT 09Z. OTHERWISE VFR AT
KMOT.
BECOMING VFR ALL TAF SITES BY 18Z. LATER TUESDAY EVENING A LARGE
AREA OF LOW/MID CLOUDINESS SHOULD MOVE NORTHWARD BRINGING MVFR CIGS
TO SOUTHERN TAF SITES OF KDIK/KBIS/KJMS AFT 02Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 AM MDT EARLY THIS MORNING FOR
NDZ031>033-040-041-043-044.
&&
$$
SHORT TERM...JV
LONG TERM...TWH
AVIATION...JV
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1130 PM CDT MON OCT 28 2013
.UPDATE...
ISSUED AT 1130 PM CDT MON OCT 28 2013
HIGH PRESSURE AND ASSOCIATED DRY AIRMASS WILL KEEP THE SHIELD UP
ACROSS THE REGION. THE 00Z NAM AND RAP INDICATE QPF ACROSS THE FAR
SOUTHERN FA...WHILE THE 00Z GFS KEEPS ALL MEASURABLE PRECIP SOUTH
OF THE FA. CONSIDERING THE SYNOPTIC SET-UP THE GFS MAKES MORE
SENSE...BUT A FEW SNOWFLAKES STILL POSSIBLE AND WILL KEEP THE
CHANCE POPS IN THE FORECAST. THE THICKER CIRRUS SHIELD NOW OVER
THE REGION AND TEMPERATURES HAVE BEEN STEADY THE PAST HOUR OR TWO.
FORECAST IS ON TRACK.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 305 PM CDT MON OCT 28 2013
FORECAST CHALLENGE WILL BE CLOUD TRENDS AND TEMPS TONIGHT AND ALSO
PCPN WITH THE NEXT SYSTEM MAINLY TUE INTO WED. MODELS REMAIN IN
DECENT AGREEMENT SO WILL CONTINUE TO UTILIZE A BLEND. AS OF LATE
THIS AFTERNOON CLOUDS WERE THINNING PRETTY EXTENSIVELY. THEREFORE
WILL START THE EVENING WITH JUST A BIT OF CLOUD COVER OVER THE FA
AND EXPECT IT TO INCREASE FROM WEST TO EAST OVERNIGHT. LOOKING AT
WIND SPEEDS BECOMING PRETTY LIGHT OR LIGHT EAST NORTHEAST SO IF
ANY AREAS STAY CLEAR TEMPS COULD DROP OFF ONCE AGAIN. WILL KEEP
COOLEST TEMPS IN THE NORTH AND NORTHEAST. AS FOR PCPN CHANCES THEY
SHOULD HOLD OFF UNTIL AFTER MIDNIGHT AT LEAST. HAVE DISCOUNTED THE
WETTEST NAM SOLUTION WHICH SHOWS A BAND OF A QUARTER INCH MOVING
ALONG THE INTERSTATE 94 CORRIDOR. ECMWF/GEM SOLUTIONS LOOK MUCH
MORE BELIEVABLE WITH THE DRY NORTHEAST SFC FLOW AND THEY HAVE
LITTLE IF ANYTHING FALLING AFTER MIDNIGHT. PREVIOUS WWD MAPS HAD
INDICATED A POTENTIAL FOR SOME FREEZING DRIZZLE BUT LATEST DAY1
HAS SHIFTED IT FURTHER SOUTH AND THIS LOOKS GOOD.
PCPN CHANCES ON TUE ARE ALSO LOOKING PRETTY MEAGER AND WILL
CONTINUE TO DISCOUNT THE NAM. OTHER MODELS SHOW ONLY MINIMAL
CHANCES ACROSS THE VERY FAR SOUTH. SHOULD HAVE A LOT MORE CLOUD
COVER ACROSS THE SOUTH WITH LITTLE ACROSS THE NORTH. ABOVE
MENTIONED TRENDS CONTINUE INTO TUE NIGHT AS WELL SO MOST OF THE FA
SHOULD STAY PCPN FREE DURING THIS TIME FRAME.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 305 PM CDT MON OCT 28 2013
THE WESTERN CUTOFF LOW WILL BEGIN TO MOVE INTO THE NORTHERN PLAINS
WED INTO THU. PCPN CHANCES WILL FINALLY INCREASE AND MAINLY ACROSS
THE SOUTH AND SOUTHEAST. MODELS HAVE BEEN WAFFLING ON THE DEGREE
OF WRAPAROUND PCPN WHICH WOULD MAINLY AFFECT EASTERN ND. SOME RUNS
HAVE BEEN DRY AND SOME WETTER BUT REGARDLESS THIS WOULD BE THE
AREA FURTHEST AWAY FROM THE MAIN RAIN BAND. CURRENT EVENT FORECAST
WOULD GIVE A HALF AN INCH OF RAIN OR SO FROM WAHPETON/BRECKENRIDGE
UP TOWARD BEMIDJI. VERY LITTLE TO NOTHING EXPECTED FROM
COOPERSTOWN TO GRAND FORKS TO ROSEAU.
WILL MAINTAIN LINGERING LIGHT PRECIPITATION CHANCES FRIDAY OVER
NORTHERN MINNESOTA MAINLY EAST OF A ROX-FSE-PKD LINE AS WRAPAROUND
MOISTURE LINGERS. TEMP PROFILES SUGGEST MOSTLY LIGHT RAIN...IF ANY
PRECIP FALLS. WEAK HIGH PRESSURE BUILDS IN ON SATURDAY THEN MODELS
DIFFER WITH NEXT PACIFIC SYSTEM FOR SUN-MON. GFS REMAINS FARTHER
SOUTH WITH SFC LOW AND PRECIP MORE ALONG THE INTERNATIONAL BORDER
WHILE 12Z GEM/ECMWF AREA TAD FARTHER NORTH WITH 12Z ECMWF THE
FARTHEST NORTH WITH SFC LOW TRACKING NORTH OF REGINA-WINNIPEG.
WILL MAINTAIN A LOW POP RIGHT ALONG THE BORDER FOR MIXED RA/SN.
OVERALL TEMPS WILL REBOUND TO NEAR NORMAL LEVELS WITH MOSTLY 40S FOR
HIGHS THU-SUN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1130 PM CDT MON OCT 28 2013
A VERY DRY AIRMASS WILL REMAIN ACROSS THE REGION THROUGH THE
PERIOD. CIRRUS WILL BE OVERHEAD THROUGH THE NIGHT INTO THE DAY ON
TUESDAY. THERE COULD BE SOME MID-LEVEL CLOUDS CLOSER THE NORTH
DAKOTA/SOUTH DAKOTA BORDER...BUT STILL VFR. LIGHT AND VARIABLE
WINDS TONIGHT WILL TURN SOUTHEAST ON TUESDAY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...TG
SHORT TERM...GODON
LONG TERM...GODON/RIDDLE
AVIATION...TG
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
953 AM EDT TUE OCT 29 2013
.SYNOPSIS...
HIGH PRESSURE WILL RACE EAST ACROSS THE GREAT LAKES REGION TO THE
EAST COAST BY TONIGHT. A STATIONARY FRONT JUST SOUTH OF THE AREA
WILL MOVE NORTH AS A WARM FRONT WEDNESDAY. LOW PRESSURE WILL MOVE
NORTHEAST ACROSS LAKE SUPERIOR THURSDAY. A COLD FRONT WILL MOVE EAST
ACROSS THE REGION LATE THURSDAY NIGHT. A REINFORCING COLD FRONT WILL
MOVE EAST ACROSS THE AREA ON SATURDAY AS LOW PRESSURE DEVELOPS OVER
LAKE HURON.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FAIR WEATHER WILL CONTINUE INTO THE AFTERNOON AS HIGH CLOUDS
GRADUALLY INCREASE ACROSS THE REGION. LINGERING FOG NEAR MNN WILL
DISSIPATE SOON. DIFFUSE WEAK FRONT OVER SOUTHERN WV AND OHIO WILL
DRIFT NORTHWARD TOWARD EVENING. HRRR TEMPERATURE FORECAST FOR THE
AFTERNOON IS SUPPORTED BY THE 12Z SOUNDINGS AT DTX AND ILN. HAVE
ONLY MADE MINOR CHANGES TO THE HIGH TEMPERATURE FORECAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
CHANGES ARE ON THE WAY IN THE UPPER LEVEL PATTERN THROUGH FRIDAY
NIGHT. WHAT IS NEARLY ZONAL FLOW TODAY WILL TREND TOWARD THE
AMPLIFICATION OF THE RIDGE JUST TO OUR WEST. THIS UPPER LEVEL
RIDGE WILL BUILD EAST OVER THE FORECAST AREA WEDNESDAY NIGHT AND
MOVE EAST OF THE REGION ON THURSDAY. THIS WILL THEN ALLOW A TROUGH
OF LOW PRESSURE ALOFT TO MOVE EAST INTO THE FORECAST AREA BY
FRIDAY AND FRIDAY NIGHT.
TONIGHT WILL STILL REMAIN QUIET UNDER THE INFLUENCE OF HIGH PRESSURE
THAT WILL SETTLE IN OVER THE EASTERN UNITED STATES. THIS SHOULD SET
THE MOTION OF THE WARM FRONT TO HEAD NORTH TOWARD THE REGION. THE
WARM FRONT WILL MOVE NORTH ACROSS THE FORECAST AREA ON WEDNESDAY.
THIS WILL BEGIN THE TRANSITION TO WARM AIR ADVECTION THAT WILL
CONTINUE THROUGH EARLY THURSDAY NIGHT.
A SURGE OF MOISTURE ASSOCIATED WITH THE WARM FRONT WILL AFFECT THE
FORECAST AREA BY LATE WEDNESDAY INTO WEDNESDAY NIGHT AND BRING WITH
IT AT LEAST A CHANCE FOR SOME SHOWERS.
NOW...THERE IS SOME HINT THAT A DRY SLOT MAY DEVELOP BEHIND THE WARM
FRONT AND AHEAD OF THE COLD FRONT ON THURSDAY ACROSS THE AREA. MODEL
SOUNDINGS INDICATE THAT SEVERE POTENTIAL WILL BE NON EXISTENT
BECAUSE OF THE EXTENSIVE CLOUD COVER AND MOISTURE PRODUCING NIL
CAPE. HOWEVER...I DO BELIEVE WE WILL SEE SOME BREAKS OF SUN DURING
THE DAY ON THURSDAY AND THERE IS A REMOTE POSSIBILITY THAT WITH DAY
TIME HEATING...TEMPERATURES COULD JUMP UP ABOUT 4 TO 5 DEGREES. THIS
WILL HELP TO PRODUCE ENOUGH CAPE AND INSTABILITY TO PRODUCE SOME
STRONG TO SEVERE THUNDERSTORMS LATE IN THE DAY THURSDAY INTO
THURSDAY EVENING. ANOTHER ISSUE IS THE FAIRLY HIGH HELICITY VALUES
EXPECTED THURSDAY AFTERNOON INDICATING THE POTENTIAL FOR ROTATING
THUNDERSTORMS. SO...IF ANY THING DEVELOPS THURSDAY...IT WILL HAVE TO
BE WATCHED CLOSELY FOR SEVERE THUNDERSTORM POTENTIAL. CURRENT
INDICATIONS ARE THAT ANY THREATS WILL BE STRONG DAMAGING WINDS BUT
WITH THE HIGH HELICITY POTENTIAL...THERE COULD BE A HIGHER THREAT
FOR SEVERE WEATHER.
COLD FRONT SWEEPS EAST OF THE AREA LATE THURSDAY NIGHT INTO FRIDAY
MORNING ENDING THE THREAT FOR SEVERE WEATHER. COLD AIR MASS BEHIND
THE COLD FRONT IS NOT EXPECTED TO BE VERY STRONG SO HIGHS ON FRIDAY
WILL ONLY BE KNOCKED DOWN A PEG OR TWO. THE TRUE COLD FRONT DOES NOT
ARRIVE UNTIL SATURDAY. A RETURN TO WINTER WEATHER SHAPING UP FOR THE
WEEKEND.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
AN UPPER TROF WILL CROSS THE AREA ON SATURDAY AND THAT WILL CAUSE A
THREAT OF SHOWERS ACROSS THE ENTIRE FORECAST AREA WITH THE BEST
CHANCE OVER THE SNOW BELT AREA...BECAUSE THE MOISTURE AND OMEGA IS
BEST. ON SATURDAY NIGHT IT COULD BE COLD ENOUGH FOR SOME RAIN AND
SNOW MIX...MAINLY OVER NORTHEAST OHIO AND NW PA. ON SUNDAY THE
AIR MASS IS DRYING OUT AND HIGH PRESSURE IS BUILDING IN QUICKLY FORM
THE WEST...HOWEVER...A THREAT OF SHOWERS WILL CONTINUE ESPECIALLY
OVER NW PA. FOR MONDAY HIGH PRESSURE WILL BE IN CONTROL WITH DRY
WEATHER. THE MODELS ARE IN GENERAL AGREEMENT. USED A BLEND OF
GUIDANCE FOR THE TEMPERATURE FORECAST. READINGS WILL BE NEAR OR JUST
BELOW NORMAL.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
HIGH PRESSURE OVER THE NORTHERN GREAT LAKES WILL KEEP A NORTHEAST
OR EAST FLOW OVER THE REGION THROUGH EARLY EVENING. SATELLITE
PICTURES AND OBSERVATIONS SHOW SOME LOW CLOUDS OVER LAKE ERIE.
THE QUESTION IS WILL THOSE CLOUDS MAKE IT INTO THE FORECAST AREA.
CONFIDENCE IS LOW BUT SOME CEILINGS COULD FORM MAINLY ALONG THE
LAKESHORE THROUGH THE MORNING. OTHERWISE SOME SCATTERED CUMULUS IS
EXPECTED WITH SOME CIRRUS THIS AFTERNOON.
SOME FOG WILL OCCUR THROUGH 14Z/10 AM EDT.
AS THE FLOW BECOMES SOUTHEAST THIS EVENING ANY REMAINING LOW
CLOUDS WILL GO AWAY AND ONLY HIGH CLOUDS WILL BE LEFT. SOME MID
CLOUDS WILL BE COMING IN FROM THE WEST LATE TONIGHT.
OUTLOOK...SOME NON-VFR POSSIBLE WEDNESDAY EVENING THROUGH FRIDAY
AND MAINLY AROUND THE SNOWBELT FRI NIGHT AND SAT.
&&
.MARINE...
HIGH PRESSURE OVER THE NORTHERN LAKES TODAY WILL DRIFT SLOWLY EAST
THROUGH WEDNESDAY NIGHT. A WARM FRONT WILL MOVE ACROSS THE LAKE
WEDNESDAY NIGHT AND THEN A COLD FRONT WILL CROSS LAKE ERIE EARLY
FRIDAY.
IN THE MEANTIME EAST WINDS WILL BE ON THE DECREASE TODAY...SO NO
SMALL CRAFT ADVISORY WILL BE NEEDED.
THE NEXT THREAT FOR A SMALL CRAFT ADVISORY WILL BE THURSDAY THROUGH
THE WEEKEND. ON THURSDAY IN A STRONG SOUTHWEST FLOW CONDITIONS
SHOULD MEET SMALL CRAFT ADVISORY CRITERIA AND THEN EARLY FRIDAY INTO
THE WEEKEND WHEN THE COLD ADVECTION STARTS. CONDITIONS COULD BE
CLOSE TO GALES FOR SHORT TIME EARLY FRIDAY AFTER THE FRONTAL
PASSAGE. ON THE EDGE WHETHER WILL COULD HAVE GALE FORCE WINDS IN THE
WARM ADVECTION. OTHERWISE THE CONDITIONS WILL BE CLOSE TO SMALL
CRAFT ADVISORY CONDITIONS FOR MUCH OF THE UPCOMING WEEKEND.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...LAPLANTE
SHORT TERM...LOMBARDY
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS NORMAN OK
652 PM CDT WED OCT 30 2013
.AVIATION...
STORMS HAVE STRUGGLED TO DEVELOP OR STRENGTHEN. BETTER CHANCES
FOR DEVELOP SHOULD ARRIVE LATER THIS EVENING AND OVERNIGHT AS
BETTER LIFT ARRIVES. MEANWHILE...IFR CEILINGS TO NEAR MFVR
CEILINGS WILL PREVAIL ACROSS CENTRAL OKLAOMA WITH MVFR CEILINGS
DEVELOPING ELSEWHERE.
A COLD FRONT WILL BRING A STRONG WIND SHIFT ON WEDNESDAY
WITH VFR CEILINGS. RECENT HRRR RUN IS FASTER WITH PUSHING
THE COLD FRONT SOUTHWARD THIS EVENING AS THIS IS PREFERRED.
&&
.PREV DISCUSSION... /ISSUED 406 PM CDT WED OCT 30 2013/
DISCUSSION...
WIDELY SCATTERED SHOWERS CONTINUE ACROSS PORTIONS OF EASTERN AND
SOUTHERN OK...WITH AN INITIAL SHORTWAVE TROUGH EXITING THE
REGION. A FEW STRONGER STORMS HAVE MANAGED TO DEVELOP ALONG THE
FRONT IN KS...BUT HAVE STRUGGLED TO MAINTAIN THEIR INTENSITY WITH
LITTLE MLCAPE IN PLAY. HIGHER INSTABILITY IS PRESENT NEAR THE
PREFRONTAL TROUGH/DRYLINE ACROSS SW OK AND W N TX. EXPECT SOME
DEVELOPMENT NEAR THERE AS ANOTHER WEAK MID LEVEL SHORTWAVE TROUGH
(SIGNS OF LIFT NOW EVIDENT ACROSS WESTERN N TX) WITHIN SW FLOW
MOVES OVERHEAD COMBINING WITH SOME ENHANCED SURFACE CONFLUENCE.
SOME HAIL MAY ACCOMPANY THE STRONGER STORMS...BUT POOR MID LEVEL
LAPSE RATES AND MARGINAL INSTABILITY MAY KEEP AT OR JUST BELOW
SEVERE LIMITS. LATER TONIGHT RAPID HEIGHT FALLS WILL OVERSPREAD
THE REGION WITH THE APPROACH OF THE UPPER TROUGH LIKELY RESULTING
IN MORE DEVELOPMENT PARTICULARLY ACROSS CENTRAL AND NORTHERN OK.
HEAVY RAINFALL ALSO APPEARS LIKELY OVER EXTREME SE OK. THE FRONT
AND MID LEVEL TROUGH AXIS BOTH APPEAR TO HAVE SLOWED SO WILL
LINGER AT LEAST SCHC POPS ACROSS THE EASTERN HALF OF THE FA...AND
SOME CHC POPS ACROSS THE NORTH ASSOCIATED WITH THE DPVA AS THE LOW
MOVES OVER THIS REGION.
THE 700MB TROUGH AXIS WILL FINALLY PASS OVER THE I35 CORRIDOR JUST
BEFORE LUNCHTIME AND RAPID CLEARING WILL FOLLOW. WINDS WILL
INITIALLY INCREASE BEHIND THE FRONT WITH MIXING...BUT DECOUPLE
QUICKLY WITH SUNSET. LOWS WILL DROP MAINLY BACK INTO THE 40S
FRIDAY. THE ANOTHER SHORTWAVE TROUGH WILL DIG SOUTHWARD FRIDAY
MORNING TRAVERSING THE LEE OF THE ROCKIES AND SWINGING ANOTHER MID
TO UPPER TROUGH AXIS ACROSS THE SOUTHERN PLAINS AND MIDWEST. A
COLDER AIRMASS WILL ACCOMPANY THIS TROUGH WITH A ~1025 HIGH IN
PLACE OVER THE LEE OF THE ROCKIES BY SAT MORNING. THIS WILL DROP
TEMPS BACK INTO THE LOW 40S AND UPPER 30S WITH SOME FREEZING
POSSIBLE CLOSER TO THE CENTER OF THE HIGH OVER NW OK. THESE COLDER
THAN NORMAL TEMPS WILL STICK AROUND UNTIL EARLY NEXT WEEK WHEN
RETURN FLOW ESTABLISHES ITSELF AHEAD OF A DIGGING MID TO UPPER
TROUGH OVER THE ROCKIES. RAIN CHANCES WILL RETURN INTO THE
EXTENDED AS MOISTURE INCREASES AHEAD OF THIS FEATURE. THE HIGHEST
CHANCES APPEAR TO BE TUESDAY WHEN A STRONG COLD FRONT IMPACTS THE
REGION.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 65 67 45 71 / 70 20 0 0
HOBART OK 62 69 45 70 / 50 10 0 0
WICHITA FALLS TX 66 72 46 75 / 40 10 0 0
GAGE OK 48 66 38 67 / 40 10 0 0
PONCA CITY OK 64 65 41 67 / 80 40 0 0
DURANT OK 71 75 50 76 / 80 20 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TULSA OK
646 PM CDT WED OCT 30 2013
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
GENERALLY MVFR CONDITIONS THROUGH 15Z. OCCASIONAL IFR
CEILINGS/VISIBILITY IN HEAVY RAIN SHOWERS AND ISOLATED
THUNDER. THUNDER CHANCES TOO LOW TO INCLUDE AT TAF SITES.
RAPID IMPROVEMENT TO VFR CONDITIONS ABOUT THE TIME OF COLD
FRONT PASSAGE... 15Z-18Z TIME FRAME.
&&
.PREV DISCUSSION... /ISSUED 309 PM CDT WED OCT 30 2013/
DISCUSSION...
MAIN FORECAST CONCERNS CONTINUE TO BE SHORT TERM FLASH FLOODING
AND ISOLATED SEVERE STORM POTENTIAL ACROSS VARIOUS PARTS OF THE
FORECAST AREA.
OVERNIGHT...THERE WILL LIKELY BE TWO DISTINCT AREAS OF CONVECTIVE
DEVELOPMENT TO AFFECT EASTERN OKLAHOMA AND NORTHWEST ARKANSAS. THE
FIRST IS ASSOCIATED WITH A STRONG LOW LEVEL JET IN SOUTHEAST
OKLAHOMA AND INTO WESTERN ARKANSAS...AND THE SECOND IS IN THE
VICINITY OF THE COLD FRONT THAT SHOULD EVENTUALLY AFFECT ALL OF
THE FORECAST AREA...PERHAPS AFTER MERGING SOMEWHAT WITH THE LOW
LEVEL JET CONVECTION.
SHOWERS AND STORMS IN NORTHEAST TEXAS AND INTO SOUTHEAST OKLAHOMA
HAVE BEEN SLOW TO BECOME ANYTHING MORE THAN SCATTERED THROUGH THE
DAY...BUT DATA INDICATE THAT THINGS SHOULD BEGIN TO FILL IN THIS
EVENING AND INTO THE OVERNIGHT. THERE IS A POSSIBILITY THAT THE
AXIS OF HEAVIEST PRECIPITATION MAY SLIDE JUST SOUTHEAST OF THE
FORECAST AREA...BUT THIS SHIFT IS STILL SOMEWHAT UNCERTAIN...
ESPECIALLY WITH THE HRRR CONTINUING TO NAIL SOUTHEAST OKLAHOMA.
NEVERTHELESS...AS THIS AREA OF STORMS BEGINS TO SET UP...IT IS
LIKELY TO STEAL SOME MOISTURE AND HEAVY RAIN POTENTIAL FROM
CONVECTION FARTHER NORTH.
FURTHER NORTHWEST...ALONG THE FRONTAL BOUNDARY...STRONG TO...AT
TIMES...SEVERE STORMS HAVE ALREADY DEVELOPED ACROSS PARTS OF SOUTH
CENTRAL KANSAS. LACK OF INSTABILITY ACROSS EASTERN OKLAHOMA SHOULD
LIMIT THE SEVERE POTENTIAL AS THEY MOVE TOWARD THE AREA...BUT
STRONG WIND FIELDS WILL KEEP A LIMITED SEVERE THREAT THIS
EVENING...ESPECIALLY NORTHWEST OF TULSA.
BAND OF PERSISTENT RAIN THAT DEVELOPED DURING THE DAY JUST SOUTH
OF THE INTERSTATE 44 CORRIDOR PRODUCED A WIDESPREAD 2 TO 3 INCHES
OF RAIN FROM NORTHERN PARTS OF OKFUSKEE COUNTY NORTHEASTWARD
TOWARD NORTHERN CHEROKEE AND SOUTHERN DELAWARE COUNTIES. ALTHOUGH
AMOUNTS OF THIS MAGNITUDE ARE NOT EXPECTED FROM THE FRONTAL PRECIP
OVERNIGHT...THE ANTECEDENT CONDITIONS WARRANT EXPANDING THE FLASH
FLOOD WATCH NORTHWARD.
STORMS WILL LIKELY LINGER INTO TOMORROW MORNING ACROSS ESPECIALLY
FAR EASTERN OKLAHOMA AND NORTHWEST ARKANSAS BEFORE BEGINNING TO
CLEAR OUT DURING THE AFTERNOON. DRY CONDITIONS WILL PERSIST
THROUGH THE WEEKEND...WITH TEMPERATURES RUNNING CLOSER TO SEASONAL
NORMALS.
ANOTHER STORM SYSTEM WILL MOVE INTO THE WESTERN UNITED STATES AND
AFFECT THE REGION DURING THE FIRST HALF OF NEXT WEEK...WITH MORE
WIDESPREAD STORMS APPEARING LIKELY AT THIS POINT. CURRENTLY...IT
LOOKS LIKE TEMPERATURES BEHIND THIS SYSTEM WILL BE LOWER THAN
BEHIND THE CURRENT ONE. ONE ITEM OF NOTE...THE CURRENT RUN OF THE
ECMWF HAS BEEN DISCOUNTED FOR THIS FORECAST...AS IT IS A HUGE
CHANGE FROM ITS PREVIOUS RUNS AND ALSO FROM THE GFS...ALL OF WHICH
POINT TO A MORE PROGRESSIVE SYSTEM AS OPPOSED TO A CLOSED LOW
SCENARIO.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 66 69 47 70 / 90 60 0 0
FSM 64 74 47 72 / 100 80 0 0
MLC 65 72 47 74 / 80 50 0 0
BVO 64 66 42 69 / 90 50 0 0
FYV 61 70 42 68 / 100 80 0 0
BYV 60 71 45 67 / 100 80 0 0
MKO 63 72 45 71 / 90 60 0 0
MIO 64 68 44 67 / 90 70 0 0
F10 65 70 47 72 / 80 50 0 0
HHW 64 76 47 75 / 100 50 10 0
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...FLASH FLOOD WATCH UNTIL 7 AM THURSDAY FOR OKZ049-OKZ053-OKZ062-
OKZ063-OKZ065-OKZ066-OKZ067-OKZ068-OKZ070-OKZ071-OKZ072-
OKZ073-OKZ074-OKZ075-OKZ076.
AR...FLASH FLOOD WATCH UNTIL 7 AM THURSDAY FOR ARZ019-ARZ020-ARZ029.
&&
$$
SHORT TERM...07
LONG TERM....07
AVIATION...21
AREA FORECAST DISCUSSION
NWS NORMAN OK
331 PM CDT TUE OCT 29 2013
.DISCUSSION...
STORM SYSTEM OVER NEVADA WILL MOVE TOWARD THE AREA BRINGING STORM
CHANCES THROUGH THURSDAY MORNING. FOR TONIGHT... WILL FIRST WATCH
FOR ANY CONVECTION THAT MIGHT DEVELOP ALONG THE SURFACE FRONT THAT
CURRENTLY EXTENDS FROM NORTH CENTRAL INTO WEST CENTRAL OKLAHOMA.
SOME INSTABILITY HAS DEVELOPED PER MESOANALYSIS DESPITE THE
CLOUDINESS. RAP... HRRR AND LOCAL WRF SUGGEST THAT SOME
DEVELOPMENT IS AT LEAST POSSIBLE LATE THIS AFTERNOON. THIS
BOUNDARY IS EXPECTED TO WASH OUT AND/OR LIFT NORTH INTO KANSAS.
WITH THIS PRIMARY FOCUS LIFTING INTO KANSAS... THE HIGHEST CHANCE
OF PRECIPITATION WILL BE ACROSS NORTHERN OKLAHOMA ALTHOUGH SOME
NUMERICAL GUIDANCE SUGGEST THAT AT LEAST THE CHANCE FOR SCATTERED
STORMS FARTHER SOUTH. STORMS ARE LIKELY AS THE STORM SYSTEM
APPROACHES WEDNESDAY AND MOVES OVER THE PLAINS THURSDAY MORNING.
HEAVY RAINFALL WILL BE POSSIBLE IN SOUTHEASTERN OKLAHOMA. DID
CONSIDER A SMALL FLASH FLOOD WATCH SOUTHEAST... BUT THE FLASH
FLOOD GUIDANCE IS STILL RELATIVELY HIGH AND THE HEAVIEST RAIN
CURRENTLY LOOKS TO FALL JUST EAST OF THE CWA.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 66 72 61 71 / 40 70 50 20
HOBART OK 65 75 58 70 / 40 50 40 10
WICHITA FALLS TX 66 77 64 73 / 50 70 40 10
GAGE OK 60 75 48 68 / 40 30 30 0
PONCA CITY OK 66 73 59 67 / 60 80 60 30
DURANT OK 66 72 67 77 / 40 90 80 30
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TULSA OK
1134 PM CDT MON OCT 28 2013
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
SCATTERED SHOWERS AND THUNDERSTORMS WILL WILL PLAGUE NORTHEAST
OKLAHOMA AND NORTHWEST ARKANSAS LATE INTO TUESDAY MORNING. THIS
WILL CREATE MVFR TO OCCASIONAL IFR CONDITIONS AT THE TAF SITES
ACROSS THIS AREA. CONDITIONS LOOKS TO IMPROVE BY TUESDAY AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 952 PM CDT MON OCT 28 2013/
DISCUSSION...
A FEW SHOWERS ARE BEGINNING TO DEVELOP ACROSS PARTS OF NORTHEAST
OKLAHOMA AT THIS TIME. THIS ACTIVITY IS EXPECTED TO CONTINUE TO
DEVELOP AND INCREASE IN BOTH COVERAGE AND INTENSITY OVERNIGHT PER
THE LATEST HRRR MODEL DATA. THE MOST WIDESPREAD SHOWERS AND STORMS
OVERNIGHT WILL LIKELY REMAIN NORTH OF INTERSTATE 44 AND THE BEST
CHANCE FOR ANY ISOLATED SEVERE STORMS WILL BE TO THE NORTH OF THE
OKLAHOMA/KANSAS BORDER.
HAVE LOWERED POPS SLIGHTLY OVERNIGHT IN MOST PLACES BASED ON THE
LATEST HRRR AND NAM MODEL RUNS. THE REST OF THE FORECAST LOOKS
GOOD AT THIS TIME.
UPDATE ON THE WAY.
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...10
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
913 PM CDT WED OCT 30 2013
.UPDATE...
AT THE SURFACE AN EFFECTIVE WARM FRONT BOUNDARY DEVELOPED TODAY
AND IS CURRENTLY LOCATED ALONG A LINE FROM NACOGDOCHES TO MEXIA TO
GRANBURY TO WICHITA FALLS. TO THE NORTH OF THIS BOUNDARY
TEMPERATURES AND DEWPOINTS ARE IN THE MID 60S...ABOUT 5 TO 7
DEGREES COOLER THAN THE AIRMASS TO THE SOUTH OF THE BOUNDARY. EVEN
SHORT TERM MODEL GUIDANCE HAS NOT REALLY CAUGHT ONTO THE PRESENCE
OF THIS BOUNDARY...WHICH IS AFFECTING THE FORECAST SURFACE
INSTABILITY FIELDS OVER THE NORTHEAST HALF OF THE REGION. IN
ADDITION...HAVE LOWERED FORECAST LOW TEMPS 5 DEGREES OR SO TO NEAR
CURRENT TEMPS IN THIS AREA. TEMPERATURES WILL BE STEADY OR RISE
SLOWLY AS THE WARM FRONT LIFTS NORTH AS THE MAIN UPPER TROUGH AND
SURFACE LOW PRESSURE SYSTEM MOVE EAST TONIGHT.
CONCERNING THE CONVECTIVE FORECAST AND HEAVY RAIN POTENTIAL. THE
RADAR IS CLEARLY SHOWING THE EFFECTS OF A LOW LEVEL TROUGH OR
BOUNDARY THAT HAS SET UP THIS EVENING RIGHT ALONG THE I-35
CORRIDOR SOUTH OF TEMPLE. THE BOUNDARY EXTENDS FROM COTULLA TO
AUSTIN TO MARLIN TO ATHENS. EVENING FWD SOUNDING INDICATED
SIGNIFICANTLY DRIER AIR NEAR 850MB AND MORE VEERED WESTERLY FLOW.
AT DEL RIO...DRY AIR AND EVEN NORTHWEST WINDS WERE PRESENT AT
850MB...SO THERE IS GOOD REASON TO BELIEVE THAT THE LOW LEVEL
BOUNDARY IS FIRMLY IN PLACE AND WILL REMAIN IN TACT THROUGH
TONIGHT ACROSS CENTRAL AND EAST TEXAS. THIS BOUNDARY WILL BE THE
FOCUS FOR TRAINING CONVECTIVE CELLS THROUGH THE NEXT 6 TO 9 HOURS
OVER THE SOUTHEAST ZONES. ALL OF THE INGREDIENTS THAT PORTEND TO
EXCESSIVE RAINFALL ARE AVAILABLE TONIGHT WITH HIGH MOISTURE
CONTENT...STRONG LOW LEVEL WINDS RESULTING IN HIGH MOISTURE
FLUX...WEAK INSTABILITY...AND HIGH FREEZING LEVELS. AM VERY
CONCERNED SOME LOCATIONS ACROSS THE SOUTHEAST ZONES MAY RECEIVE
OVER 6 INCHES OF RAIN TONIGHT...WHICH RAISES CONCERN FOR A
SIGNIFICANT FLASH FLOODING EVENT THAT IS A THREAT TO LIFE AND
PROPERTY.
WITH THE BAND OF CONVECTION SETTING UP IN THIS LOCATION...AND THE
PRESENCE OF DRIER AND MORE STABLE AIR OVER THE NORTHEAST ZONES
HAVE CANCELED THE WATCH OVER THE NORTHEAST ZONES...INCLUDING
ROCKWALL AND KAUFMAN COUNTIES. ADDITIONAL RAIN IS LIKELY IN THESE
AREAS TONIGHT...BUT HEAVY RAIN THREAT IS LESSENING. THE FORT
WORTH SOUNDING DID INDICATE A LAYER OF MOIST/CONDITIONALLY
UNSTABLE PARCELS JUST ABOVE THE COOLER SURFACE LAYER. WHEN THE
NEXT PIECE OF UPPER LEVEL ENERGY THAT IS NOW LOCATED IN NEW MEXICO
ROTATES OUT INTO THE SOUTHERN PLAINS...THIS SHOULD BE CONVERTED
INTO SCATTERED SHOWERS AND STORMS OVER THE REMAINDER OF THE AREA
NORTH OF THE TRAINING BAND OF HEAVY RAINFALL. THIS MAY WAIT UNTIL
THE COLD FRONT ARRIVES LAET TONIGHT AND A SURFACE/LOW LEVEL
TRIGGER BECOMES AVAILABLE. FOR THIS REASON WILL KEEP POPS HIGH
OVER THE AREA...BUT THE THREAT FOR HEAVY RAINFALL WILL BE LIMITED
BY QUICK DURATION AND THE THREAT FOR SEVERE WEATHER WILL BE
LIMITED BY MOIST ADIABATIC LAPSE RATES ALOFT.
TR.92
&&
.AVIATION...
A MESOSCALE BOUNDARY SEPARATING RAIN COOLED AIR TO THE NORTH AND
WARM...UNSTABLE AIR TO THE SOUTH CONTINUES TO LIFT NORTHEAST INTO
THE METROPLEX. THIS SHOULD ALLOW FOR IMPROVING CIGS AT METROPLEX
TAF SITES...AND WILL INDICATE IFR CONDITIONS IMPROVING TO MVFR
AT 01-02Z. SCATTERED THUNDERSTORMS WILL REMAIN A POSSIBILITY IN
THE WARM UNSTABLE AIR FOR ANOTHER COUPLE OF HOURS....WITH MOST OF
THE THUNDERSTORM ACTIVITY REMAINING EAST AND SOUTH OF THE TAF
SITES WHERE THE HIGHEST MOISTURE RESIDES. FOR THE NEAR
TERM...RADAR TRENDS INDICATE THAT KACT WILL HAVE A GREATER
POTENTIAL OF BEING AFFECTED THAN THE METROPLEX AND WILL CONTINUE
WITH VCTS THERE WITH VCSH IN THE METROPLEX THROUGH 06Z. OTHERWISE
SURFACE WINDS HAD BACKED TO A MORE EASTERLY COMPONENT NORTH OF THE
SURFACE BOUNDARY...BUT SHOULD BECOME MORE SOUTHERLY AREA-WIDE AS
THE BOUNDARY MOVES NORTH OF ALL TAF SITES. SPEEDS IN THE 10-15 KT
RANGE WILL INCREASE TO 15-20 KT AROUND MIDNIGHT LOCAL AS THE LOW
LEVEL JET BECOMES ESTABLISHED.
THE MAIN UPPER TROUGH AXIS IS CURRENTLY OVER THE 4-CORNERS REGION
AND STEADILY APPROACHING WEST TEXAS. CONVECTION WILL BECOME MORE
WIDESPREAD LATER THIS EVENING AS ASCENT FROM THIS SYSTEM SPREADS
OVERHEAD. HI-RES MODEL DATA SUGGESTS THUNDERSTORMS REDEVELOPING
NEAR ALL TAF LOCATIONS AROUND 06Z THEN SHIFTING EAST OF TAF
LOCATIONS AROUND 10Z. SOUTH WINDS WILL BECOME WEST MID TO LATE
MORNING THURSDAY AS A PACIFIC FRONT PUSHES EAST ACROSS THE
AREA...WITH WINDS VEERING TO THE NORTHWEST BY EARLY AFTERNOON.
FOR DFW...THE MAIN IMPACT THURSDAY WILL BE CROSSWINDS LATE MORNING
THEN NORTHWEST WINDS SHORTLY AFTER 18Z. OTHERWISE CONDITIONS ARE
EXPECTED TO BE VFR THURSDAY.
30
&&
.PREV DISCUSSION... /ISSUED 401 PM CDT WED OCT 30 2013/
THE NEXT 18 HOURS WILL BE QUITE UNSETTLED ACROSS NORTH TEXAS WITH
PERIODS OF SHOWERS AND THUNDERSTORMS AND THE POTENTIAL FOR BOTH
SEVERE WEATHER AND FLASH FLOODING. WHILE MOST AREAS WILL PICK UP
SOME RAINFALL THROUGH LATE TONIGHT...THE MAIN CHALLENGE WILL BE
NARROWING DOWN THE HIGHEST POTENTIAL FOR HEAVY RAINFALL AND FLASH
FLOODING. THERE ARE A COUPLE OF COMPLICATING FACTORS THAT COULD
HAVE SIGNIFICANT IMPACTS ON THE SHORT TERM FORECAST INCLUDING THE
POTENTIAL FOR UNDERESTIMATING THE SEVERE THREAT.
CONCERNING THE SHORT TERM SEVERE WEATHER THREAT...LATEST SATELLITE
IMAGERY SHOWS SUBSTANTIAL BREAKS IN THE CLOUD COVER ACROSS THE
FAR SOUTHERN PARTS OF THE CWA INTO SOUTHEAST TEXAS. THIS IS
IMPORTANT BECAUSE TEMPERATURES IN HENDERSON AND ANDERSON COUNTIES
ARE IN THE MID 60S WHILE TEMPERATURE ACROSS BELL AND MILAM
COUNTIES ARE IN THE LOWER 80S. THIS DIFFERENTIAL HEATING BOUNDARY
WILL EFFECTIVELY ACT AS A WARM FRONT WITH STRONGLY BACKED WINDS TO
THE NORTH OF THE BOUNDARY. LOCALLY RUN SEVERE PARAMETERS INDICATE
AROUND 2000J/KG OF SURFACE BASED CAPE WITH LITTLE INHIBITION. MORE
IMPORTANTLY...LOW LEVEL TURNING OF THE WINDS IS QUITE STRONG AND
THERE IS AMPLE LOW LEVEL CAPE. GIVEN THE VERY HIGH SURFACE
DEWPOINTS...LCLS ARE LOW AND THIS AREA WOULD NEED TO BE MONITORED
FOR A LOCALLY ENHANCED TORNADO THREAT ESPECIALLY IF STORMS DEVELOP
ALONG THE BOUNDARY ITSELF.
ELSEWHERE...THERE IS A POTENTIAL FOR MORE ISOLATED SEVERE
THUNDERSTORMS THROUGH THE NIGHT ACROSS NORTH TEXAS GIVEN AMPLE
DEEP LAYER SHEAR OF AROUND 50KTS. WITH DEEP MOISTURE IN
PLACE...LAPSE RATES ARE NOT OVERLY STEEP BUT A MARGINALLY SEVERE
HAIL THREAT WOULD EXIST. THERE IS A LAYER OF MID LEVEL DRY AIR
OVER NORTH TEXAS WHICH COULD ENHANCE DOWNDRAFTS LOCALLY SUPPORTING
A LOW END DAMAGING WIND THREAT.
THE MORE SIGNIFICANT HAZARD ACROSS NORTH TEXAS APPEARS TO BE THE
POTENTIAL FOR FLASH FLOODING THROUGH TONIGHT. THE MID LEVEL DRY
AIR MENTIONED ABOVE HAS BEEN A THORN IN OUR SIDE IN TRYING TO
DETERMINE THE LOCATION OF HEAVIEST RAINFALL. MODEL GUIDANCE
CONTINUES TO INDICATE AT LEAST WEAK SUBSIDENCE INCREASING ACROSS
THE WESTERN HALF OF THE CWA THROUGH LATE THIS EVENING. AIRCRAFT
SOUNDINGS FROM DFW AND DAL SHOW THIS LAYER OF DRY AIR FROM ABOUT
700MB TO 550MB. MORE IMPORTANTLY...LATEST SOUNDINGS INDICATE THAT
THIS DRY AIR IS SINKING...IMPLYING DOWNWARD VERTICAL MOTIONS.
LATEST FORECAST WILL FOLLOW THE ASSUMPTION THAT SOME DRIER AIR
WILL REMAIN IN PLACE ACROSS THE WESTERN HALF OF THE CWA...OR MORE
SPECIFIC...FROM SOUTHWEST TO NORTHEAST ACROSS THE CWA FROM NEAR
GOLDTHWAITE TO HILLSBORO TO SHERMAN. THIS WILL BE IN THE FORM OF A
TIGHT THETA-E BOUNDARY ALONG THESE AREAS. AS THE MAIN UPPER LOW
EJECTS EASTWARD LATER TONIGHT LARGE SCALE FORCING WILL CONTINUE TO
INCREASE. THE COVERAGE OF SHOWERS AND THUNDERSTORMS SHOULD
INCREASE DRAMATICALLY AFTER DARK...MAINLY FROM 9PM TO 2AM. THE
AFOREMENTIONED THETA-E BOUNDARY THEN BECOMES ESPECIALLY IMPORTANT
BECAUSE MOST OF THE HEAVY PRECIPITATION WILL BE ALONG AND EAST OF
THIS BOUNDARY. WITH A 50KT LLJ PUMPING RICH MOISTURE INTO THIS
SYSTEM...EXPECT SEVERAL HOURS OF TRAINING SHOWERS AND
THUNDERSTORMS...MAINLY ACROSS THE EAST AND SOUTHEAST COUNTIES. THE
CURRENT FLASH FLOOD WATCH HIGHLIGHTS THE AREAS WHERE WE THINK THE
BEST CHANCE FOR TRAINING THUNDERSTORMS EXISTS. OF COURSE...IF THIS
IS OFF ANY BIT...CONSIDERABLY HEAVIER RAINFALL COULD FALL FARTHER
WEST. THE LAST FEW RUNS OF THE HRRR SEEM TO SUGGEST THAT MUCH
HEAVIER RAINFALL WILL FALL WEST...BUT IT SEEMS TO BE THE OUTLIER
AT THIS TIME AND DOESNT APPEAR TO BE HANDLING THE DRY AIR AS WELL.
THAT BEING SAID...CURRENT FLASH FLOOD WATCH CONFIGURATION WILL
REMAIN THE SAME...BUT IF IT BECOMES APPARENT THAT HEAVIER RAINFALL
WILL OCCUR WEST...WE WILL EXPAND IT THIS EVENING. WITH PWS IN
EXCESS OF 2 INCHES...WHICH IS ANOMALOUSLY HIGH FOR LATE
OCTOBER...AND SURFACE TO 700MB THETA-E DIFFERENCE OF ONLY ABOUT 5
DEG K...VERY HEAVY RAINFALL IS EXPECTED. THUNDERSTORMS SHOULD BE
ABLE TO MAINTAIN EXTREMELY EFFICIENT RAINFALL RATES FOR AN
EXTENDED PERIOD OF TIME. RAINFALL AMOUNTS IN THE WATCH AREA SHOULD
AVERAGE 3 TO 5 INCHES WITH ISOLATED AMOUNTS IN EXCESS OF 7 INCHES.
ALL OF THIS ACTIVITY SHOULD MOVE EAST DURING THE MORNING HOURS
THURSDAY WITH MUCH DRIER AIR MOVING IN. WINDS WILL DIMINISH DURING
THE DAY AND TRICK OR TREATING WEATHER SHOULD BE QUITE NICE. THE
MAIN UPPER TROUGH WILL MOVE EAST AND A LARGE SURFACE HIGH WILL
BUILD IN FOR THE WEEKEND. THIS SHOULD BE SHORT LIVED AS ANOTHER
STRONG SYSTEM MOVES INTO THE WESTERN US EARLY NEXT WEEK. MOISTURE
WILL BE QUICK TO RETURN WITH RAIN CHANCES FOR MONDAY AND TUESDAY.
DUNN
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 66 79 53 77 50 / 80 20 5 0 0
WACO, TX 68 79 47 77 47 / 90 20 5 0 0
PARIS, TX 63 78 50 74 46 / 100 20 5 0 0
DENTON, TX 65 75 50 74 43 / 80 10 5 0 0
MCKINNEY, TX 64 76 50 76 46 / 100 20 5 0 0
DALLAS, TX 66 79 54 78 52 / 90 20 5 0 0
TERRELL, TX 64 78 50 76 47 / 100 20 5 0 0
CORSICANA, TX 64 80 52 75 50 / 100 30 5 0 0
TEMPLE, TX 69 79 48 78 49 / 100 30 5 0 0
MINERAL WELLS, TX 67 75 44 76 45 / 60 10 5 0 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR TXZ122-123-135-
146>148-158-160>162-174-175.
&&
$$
/
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
613 PM CDT WED OCT 30 2013
.AVIATION...
A MESOSCALE BOUNDARY SEPARATING RAIN COOLED AIR TO THE NORTH AND
WARM...UNSTABLE AIR TO THE SOUTH CONTINUES TO LIFT NORTHEAST INTO
THE METROPLEX. THIS SHOULD ALLOW FOR IMPROVING CIGS AT METROPLEX
TAF SITES...AND WILL INDICATE IFR CONDITIONS IMPROVING TO MVFR
AT 01-02Z. SCATTERED THUNDERSTORMS WILL REMAIN A POSSIBILITY IN
THE WARM UNSTABLE AIR FOR ANOTHER COUPLE OF HOURS....WITH MOST OF
THE THUNDERSTORM ACTIVITY REMAINING EAST AND SOUTH OF THE TAF
SITES WHERE THE HIGHEST MOISTURE RESIDES. FOR THE NEAR
TERM...RADAR TRENDS INDICATE THAT KACT WILL HAVE A GREATER
POTENTIAL OF BEING AFFECTED THAN THE METROPLEX AND WILL CONTINUE
WITH VCTS THERE WITH VCSH IN THE METROPLEX THROUGH 06Z. OTHERWISE
SURFACE WINDS HAD BACKED TO A MORE EASTERLY COMPONENT NORTH OF THE
SURFACE BOUNDARY...BUT SHOULD BECOME MORE SOUTHERLY AREA-WIDE AS
THE BOUNDARY MOVES NORTH OF ALL TAF SITES. SPEEDS IN THE 10-15 KT
RANGE WILL INCREASE TO 15-20 KT AROUND MIDNIGHT LOCAL AS THE LOW
LEVEL JET BECOMES ESTABLISHED.
THE MAIN UPPER TROUGH AXIS IS CURRENTLY OVER THE 4-CORNERS REGION
AND STEADILY APPROACHING WEST TEXAS. CONVECTION WILL BECOME MORE
WIDESPREAD LATER THIS EVENING AS ASCENT FROM THIS SYSTEM SPREADS
OVERHEAD. HI-RES MODEL DATA SUGGESTS THUNDERSTORMS REDEVELOPING
NEAR ALL TAF LOCATIONS AROUND 06Z THEN SHIFTING EAST OF TAF
LOCATIONS AROUND 10Z. SOUTH WINDS WILL BECOME WEST MID TO LATE
MORNING THURSDAY AS A PACIFIC FRONT PUSHES EAST ACROSS THE
AREA...WITH WINDS VEERING TO THE NORTHWEST BY EARLY AFTERNOON.
FOR DFW...THE MAIN IMPACT THURSDAY WILL BE CROSSWINDS LATE MORNING
THEN NORTHWEST WINDS SHORTLY AFTER 18Z. OTHERWISE CONDITIONS ARE
EXPECTED TO BE VFR THURSDAY.
30
&&
.PREV DISCUSSION... /ISSUED 401 PM CDT WED OCT 30 2013/
THE NEXT 18 HOURS WILL BE QUITE UNSETTLED ACROSS NORTH TEXAS WITH
PERIODS OF SHOWERS AND THUNDERSTORMS AND THE POTENTIAL FOR BOTH
SEVERE WEATHER AND FLASH FLOODING. WHILE MOST AREAS WILL PICK UP
SOME RAINFALL THROUGH LATE TONIGHT...THE MAIN CHALLENGE WILL BE
NARROWING DOWN THE HIGHEST POTENTIAL FOR HEAVY RAINFALL AND FLASH
FLOODING. THERE ARE A COUPLE OF COMPLICATING FACTORS THAT COULD
HAVE SIGNIFICANT IMPACTS ON THE SHORT TERM FORECAST INCLUDING THE
POTENTIAL FOR UNDERESTIMATING THE SEVERE THREAT.
CONCERNING THE SHORT TERM SEVERE WEATHER THREAT...LATEST SATELLITE
IMAGERY SHOWS SUBSTANTIAL BREAKS IN THE CLOUD COVER ACROSS THE
FAR SOUTHERN PARTS OF THE CWA INTO SOUTHEAST TEXAS. THIS IS
IMPORTANT BECAUSE TEMPERATURES IN HENDERSON AND ANDERSON COUNTIES
ARE IN THE MID 60S WHILE TEMPERATURE ACROSS BELL AND MILAM
COUNTIES ARE IN THE LOWER 80S. THIS DIFFERENTIAL HEATING BOUNDARY
WILL EFFECTIVELY ACT AS A WARM FRONT WITH STRONGLY BACKED WINDS TO
THE NORTH OF THE BOUNDARY. LOCALLY RUN SEVERE PARAMETERS INDICATE
AROUND 2000J/KG OF SURFACE BASED CAPE WITH LITTLE INHIBITION. MORE
IMPORTANTLY...LOW LEVEL TURNING OF THE WINDS IS QUITE STRONG AND
THERE IS AMPLE LOW LEVEL CAPE. GIVEN THE VERY HIGH SURFACE
DEWPOINTS...LCLS ARE LOW AND THIS AREA WOULD NEED TO BE MONITORED
FOR A LOCALLY ENHANCED TORNADO THREAT ESPECIALLY IF STORMS DEVELOP
ALONG THE BOUNDARY ITSELF.
ELSEWHERE...THERE IS A POTENTIAL FOR MORE ISOLATED SEVERE
THUNDERSTORMS THROUGH THE NIGHT ACROSS NORTH TEXAS GIVEN AMPLE
DEEP LAYER SHEAR OF AROUND 50KTS. WITH DEEP MOISTURE IN
PLACE...LAPSE RATES ARE NOT OVERLY STEEP BUT A MARGINALLY SEVERE
HAIL THREAT WOULD EXIST. THERE IS A LAYER OF MID LEVEL DRY AIR
OVER NORTH TEXAS WHICH COULD ENHANCE DOWNDRAFTS LOCALLY SUPPORTING
A LOW END DAMAGING WIND THREAT.
THE MORE SIGNIFICANT HAZARD ACROSS NORTH TEXAS APPEARS TO BE THE
POTENTIAL FOR FLASH FLOODING THROUGH TONIGHT. THE MID LEVEL DRY
AIR MENTIONED ABOVE HAS BEEN A THORN IN OUR SIDE IN TRYING TO
DETERMINE THE LOCATION OF HEAVIEST RAINFALL. MODEL GUIDANCE
CONTINUES TO INDICATE AT LEAST WEAK SUBSIDENCE INCREASING ACROSS
THE WESTERN HALF OF THE CWA THROUGH LATE THIS EVENING. AIRCRAFT
SOUNDINGS FROM DFW AND DAL SHOW THIS LAYER OF DRY AIR FROM ABOUT
700MB TO 550MB. MORE IMPORTANTLY...LATEST SOUNDINGS INDICATE THAT
THIS DRY AIR IS SINKING...IMPLYING DOWNWARD VERTICAL MOTIONS.
LATEST FORECAST WILL FOLLOW THE ASSUMPTION THAT SOME DRIER AIR
WILL REMAIN IN PLACE ACROSS THE WESTERN HALF OF THE CWA...OR MORE
SPECIFIC...FROM SOUTHWEST TO NORTHEAST ACROSS THE CWA FROM NEAR
GOLDTHWAITE TO HILLSBORO TO SHERMAN. THIS WILL BE IN THE FORM OF A
TIGHT THETA-E BOUNDARY ALONG THESE AREAS. AS THE MAIN UPPER LOW
EJECTS EASTWARD LATER TONIGHT LARGE SCALE FORCING WILL CONTINUE TO
INCREASE. THE COVERAGE OF SHOWERS AND THUNDERSTORMS SHOULD
INCREASE DRAMATICALLY AFTER DARK...MAINLY FROM 9PM TO 2AM. THE
AFOREMENTIONED THETA-E BOUNDARY THEN BECOMES ESPECIALLY IMPORTANT
BECAUSE MOST OF THE HEAVY PRECIPITATION WILL BE ALONG AND EAST OF
THIS BOUNDARY. WITH A 50KT LLJ PUMPING RICH MOISTURE INTO THIS
SYSTEM...EXPECT SEVERAL HOURS OF TRAINING SHOWERS AND
THUNDERSTORMS...MAINLY ACROSS THE EAST AND SOUTHEAST COUNTIES. THE
CURRENT FLASH FLOOD WATCH HIGHLIGHTS THE AREAS WHERE WE THINK THE
BEST CHANCE FOR TRAINING THUNDERSTORMS EXISTS. OF COURSE...IF THIS
IS OFF ANY BIT...CONSIDERABLY HEAVIER RAINFALL COULD FALL FARTHER
WEST. THE LAST FEW RUNS OF THE HRRR SEEM TO SUGGEST THAT MUCH
HEAVIER RAINFALL WILL FALL WEST...BUT IT SEEMS TO BE THE OUTLIER
AT THIS TIME AND DOESNT APPEAR TO BE HANDLING THE DRY AIR AS WELL.
THAT BEING SAID...CURRENT FLASH FLOOD WATCH CONFIGURATION WILL
REMAIN THE SAME...BUT IF IT BECOMES APPARENT THAT HEAVIER RAINFALL
WILL OCCUR WEST...WE WILL EXPAND IT THIS EVENING. WITH PWS IN
EXCESS OF 2 INCHES...WHICH IS ANOMALOUSLY HIGH FOR LATE
OCTOBER...AND SURFACE TO 700MB THETA-E DIFFERENCE OF ONLY ABOUT 5
DEG K...VERY HEAVY RAINFALL IS EXPECTED. THUNDERSTORMS SHOULD BE
ABLE TO MAINTAIN EXTREMELY EFFICIENT RAINFALL RATES FOR AN
EXTENDED PERIOD OF TIME. RAINFALL AMOUNTS IN THE WATCH AREA SHOULD
AVERAGE 3 TO 5 INCHES WITH ISOLATED AMOUNTS IN EXCESS OF 7 INCHES.
ALL OF THIS ACTIVITY SHOULD MOVE EAST DURING THE MORNING HOURS
THURSDAY WITH MUCH DRIER AIR MOVING IN. WINDS WILL DIMINISH DURING
THE DAY AND TRICK OR TREATING WEATHER SHOULD BE QUITE NICE. THE
MAIN UPPER TROUGH WILL MOVE EAST AND A LARGE SURFACE HIGH WILL
BUILD IN FOR THE WEEKEND. THIS SHOULD BE SHORT LIVED AS ANOTHER
STRONG SYSTEM MOVES INTO THE WESTERN US EARLY NEXT WEEK. MOISTURE
WILL BE QUICK TO RETURN WITH RAIN CHANCES FOR MONDAY AND TUESDAY.
DUNN
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 70 79 53 77 50 / 80 20 5 0 0
WACO, TX 70 79 47 77 47 / 100 20 5 0 0
PARIS, TX 68 78 50 74 46 / 100 20 5 0 0
DENTON, TX 67 75 50 74 43 / 80 10 5 0 0
MCKINNEY, TX 69 76 50 76 46 / 100 20 5 0 0
DALLAS, TX 72 79 54 78 52 / 90 20 5 0 0
TERRELL, TX 71 78 50 76 47 / 100 20 5 0 0
CORSICANA, TX 70 80 52 75 50 / 100 30 5 0 0
TEMPLE, TX 71 79 48 78 49 / 100 30 5 0 0
MINERAL WELLS, TX 67 75 44 76 45 / 60 10 5 0 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR TXZ095-105>107-
120>123-135-146>148-158-160>162-174-175.
&&
$$
30/92
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
158 PM CDT TUE OCT 29 2013
.AVIATION...
FOR THE 18Z TAFS...TIMING OF MVFR CIGS AND THE ONSET OF
PRECIPITATION ACROSS THE REGION IS THE PRIMARY AVIATION WEATHER
CONCERN THROUGH THE VALID FORECAST PERIOD.
MVFR CIGS REMAINED IN PLACE ACROSS ALL AREA TAF SITES AT THE START
OF THE VALID FORECAST PERIOD. LATEST RAP SOUNDINGS AND UPSTREAM
TRENDS INDICATE CIGS SHOULD LIFT ABOVE 2 KFT BY 3 PM CDT...LIFTING
TO VFR LEVELS BY 6 PM CDT. MVFR CIGS ARE LIKELY TO RETURN TO THE
REGION LATE TONIGHT AS WEAK WARM AIR ADVECTION ASSOCIATED WITH A
RELATIVELY STRONG LOW LEVEL JET OF 40 TO 45 KTS WILL PROVIDE SOME
GRADUAL MOIST LIFT OVERNIGHT OVER THE REGION. ONCE IN PLACE...MVFR
CIGS WILL LIKELY PERSIST THROUGHOUT THE DAY ON WEDNESDAY AS AN
UNSEASONABLY DEEP MOIST AIR MASS HOLDS OVER THE AREA THROUGH
THURSDAY AFTERNOON.
ISOLATED TO SCATTERED RAIN SHOWERS ARE POSSIBLE ANYTIME FROM THIS
EVENING THROUGH TOMORROW MORNING. AT THIS TIME THESE RAIN CHANCES
WERE TOO LOW TO MENTION IN THE TAFS...SO JUST HAVE CHANGE GROUPS
IN THE EARLY PART OF THE TAF FOR CIG HEIGHTS. WIDESPREAD RAIN
SHOWERS ARE MORE LIKELY TOMORROW MORNING...AND HAVE A VCSH IN AT
ALL AREA TAFS STARTING AT 15Z AS A RESULT. THUNDERSTORMS ARE MOST
LIKELY TO AFFECT AREA TAF SITES WEDNESDAY AFTERNOON WHICH WAS
BEYOND THE VALID FORECAST PERIOD FOR ALL SITES BUT DFW. WILL
LIKELY NEED TO MAKE CHANGES TO THE TAFS WITH REGARDS TO THE TIMING
OF PRECIPITATION IN FUTURE FORECASTS.
CAVANAUGH
&&
.PREV DISCUSSION... /ISSUED 403 AM CDT TUE OCT 29 2013/
AN UPPER LEVEL LOW CURRENTLY OVER NORTHERN NEVADA WILL MOVE EAST
ACROSS THE NORTHERN AND CENTRAL PLAINS WEDNESDAY AFTERNOON
THROUGH THURSDAY MORNING. MODELS ARE IN GOOD AGREEMENT WITH THE
TRACK AND TIMING OF THIS SYSTEM. WE WILL CONTINUE TO SEE AN
INCREASE IN BOTH LOW LEVEL AND MID/UPPER LEVEL MOISTURE AHEAD OF
THIS SYSTEM. PRECIPITABLE WATER VALUES EXPECTED TO CLIMB TO 1.5
TO OVER 2 INCHES BY WEDNESDAY MORNING. THIS WILL PUT MOST OF THE
FORECAST AREA 2 STANDARD DEVIATIONS ABOVE CLIMATOLOGICAL NORMALS
AND NEAR THE 99TH PERCENTILE. HAVE PLACED A MENTION OF HEAVY RAIN
IN THE FORECAST FOR THE WEDNESDAY AND WEDNESDAY NIGHT PERIOD.
RAINFALL TOTALS FOR THE EVENT WILL LIKELY AVERAGE FROM AROUND 1
INCH ACROSS THE NORTHWESTERN MOST COUNTIES TO 2 TO 4 INCHES
ACROSS THE AREA ALONG AND EAST OF THE I-35 CORRIDOR. WE WILL
LIKELY BE ISSUING A FLASH FLOOD WATCH FOR THE EASTERN TWO THIRDS
OF THE FORECAST AREA FOR THE WEDNESDAY AND WEDNESDAY NIGHT PERIOD
LATER THIS MORNING OR THIS AFTERNOON. THERE WILL ALSO BE THE
POTENTIAL FOR SOME STORMS TO BECOME SEVERE WITH LARGE HAIL AND
DAMAGING WINDS BEING THE THREATS.
AS THE TROUGH MOVES EAST...A COLD FRONT WILL MOVE INTO THE
WESTERN PART OF THE FORECAST AREA AFTER MIDNIGHT WEDNESDAY NIGHT
AND THIS FRONT WILL MOVE TO THE EAST OF THE FORECAST AREA BY
MIDDAY. SOME HEAVY RAIN MAY CONTINUE INTO THURSDAY MORNING ACROSS
THE SOUTHEASTERN THIRD OF THE FORECAST AREA. THE RAIN WILL END
WEST OF A PARIS... CORSICANA...TEMPLE LINE BY MIDDAY THURSDAY AND
END ACROSS THE REST OF THE FORECAST AREA DURING THE AFTERNOON.
DRY WEATHER IS THEN EXPECTED FOR THE REST OF THURSDAY THROUGH
SUNDAY. WE WILL BE IN NORTHWESTERLY FLOW ALOFT IN THE WAKE OF THE
EXITING UPPER TROUGH FRIDAY THROUGH SATURDAY MORNING. UPPER LEVEL
RIDGING WILL TRANSIT TEXAS SATURDAY AFTERNOON THROUGH SUNDAY
MORNING AS ANOTHER UPPER LEVEL TROUGH DIGS INTO THE WESTERN U.S.
THIS WILL PUT US IN SOUTHWESTERLY FLOW ALOFT FOR SUNDAY AFTERNOON
INTO THE EARLY PART OF NEXT WEEK. RAIN CHANCES WILL RETURN TO THE
FORECAST AREA SUNDAY NIGHT AND CONTINUE THROUGH TUESDAY. WE WILL
THEN DRY OUT TUESDAY NIGHT AS THE UPPER LEVEL TROUGH MOVES OFF TO
THE EAST.
58
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 80 69 77 69 80 / 20 40 80 90 30
WACO, TX 81 67 77 68 81 / 10 40 80 90 40
PARIS, TX 79 66 75 67 77 / 20 40 80 90 50
DENTON, TX 79 65 73 67 77 / 20 50 80 80 30
MCKINNEY, TX 79 68 75 68 78 / 20 40 80 90 30
DALLAS, TX 80 71 77 71 81 / 20 40 80 90 30
TERRELL, TX 81 69 76 69 79 / 10 40 80 90 50
CORSICANA, TX 81 68 77 70 79 / 10 30 70 90 50
TEMPLE, TX 81 68 77 69 80 / 10 40 70 90 50
MINERAL WELLS, TX 79 66 77 65 76 / 20 60 80 70 20
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
642 AM CDT TUE OCT 29 2013
.DISCUSSION...UPDATED FOR 06 AVIATION.
&&
.AVIATION...MIX OF VFR/MVFR CEILINGS EXIST ACROSS SOUTH TEXAS
TERMINALS THIS MORNING. ANY MVFR CEILINGS WILL MIX OUT BY 14Z OR
15Z. SOUTHEAST TO SOUTH SOUTHEAST WINDS WILL INCREASE TODAY WITH
SOME GUSTS BETWEEN 25 AND 30 KNOTS THIS AFTERNOON. WINDS WILL
DIMINISH AROUND 00Z...BUT REMAIN ELEVATED AT LRD THROUGH THE
EVENING. LLJ OF 30 TO 35 KNOTS WILL DEVELOP TONIGHT WHICH SHOULD
KEEP FOG POTENTIAL LOW...BUT MVFR STRATUS WILL AGAIN BE COMMON.
CEILINGS MAY FALL BELOW MVFR TONIGHT...BUT CONFIDENCE IS TOO LOW
TO MENTION IN THE TAFS ATTM.
&&
.PREV DISCUSSION... /ISSUED 432 AM CDT TUE OCT 29 2013/
SHORT TERM (TODAY THROUGH WEDNESDAY)...DEEP SOUTHERLY FLOW
THROUGH THE LOWER PARTS OF THE ATMOSPHERE WILL BRING MOISTURE BACK
INTO SOUTH TEXAS DURING THE SHORT TERM. STRATUS HAS DEVELOPED
ACROSS MUCH OF SOUTH TEXAS OVERNIGHT BUT ANTICIPATE THE LOW
CLOUDS TO MIX OUT LATER THIS MORNING. LATEST RUN HRRR PICKING UP
ON SOME SHOWER ACTIVITY THROUGH THE MORNING AND HAVE INCLUDED A 10
POP WITH MENTION OF SHOWERS THROUGH 18Z. UPPER LOW OVER THE
WESTERN CONUS WILL SLOWLY MOVE TO THE EAST TODAY...INTO FOUR
CORNERS REGION ON WEDNESDAY. PRESSURE GRADIENT WILL STRENGTHEN
OVER SOUTH TEXAS TODAY WITH SOUTHEASTERLY WINDS INCREASING BY THE
AFTERNOON. SOME GUSTS AROUND 30 MPH WILL BE POSSIBLE ACROSS THE
COASTAL BEND AND OVER THE RIO GRANDE PLAINS. HIGH TEMPS TODAY WILL
AGAIN BE ABOVE NORMAL WITH UPPER 80S ACROSS EASTERN SECTIONS TO
LOWER 90S OUT WEST. ON WEDNESDAY...DEEPER MOISTURE WILL GET DRAWN
INTO SOUTH TEXAS AS LOW LEVEL FLOW REMAINS OUT OF THE SE AND SSE.
PW VALUES WILL CLIMB TO NEAR 2 INCHES (2.1 INCHES IF THE GFS
VERIFIES) AS DISTURBANCE SCOOTS TO THE NORTH OF THE AREA. HIGHEST
CHANCES FOR SHOWERS AND STORMS ON WEDNESDAY WILL EXIST ACROSS THE
NORTHEAST ZONES WHERE CAPPING WILL BE THE WEAKEST. POPS RANGE FROM
SLIGHT CHANCE OVER THE SOUTHWEST ZONES TO LIKELY IN THE NORTHEAST
SECTIONS. TEMPS ON WEDNESDAY WILL BE SIMILAR TO TODAY...EXCEPT
OVER THE NORTHEAST WHERE BETTER RAIN CHANCES AND CLOUD COVER MAY
KEEP TEMPS DOWN A FEW DEGREES. YET ANOTHER BREEZY TO WINDY DAY ON
WEDNESDAY IN ADVANCE OF THURSDAY/S FROPA.
MARINE/COASTAL...ONSHORE FLOW BEGIN TO INCREASE ACROSS THE GULF
WATERS TODAY AS GRADIENT STRENGTHENS OVER THE AREA. SMALL CRAFT
ADVISORY CONDITIONS WILL DEVELOP THIS EVENING WITH WINDS OF 20 TO
25 KNOTS. IN ADDITION...SEAS WILL CLIMB TO 7 TO 8 FEET OVER THE
WATERS. THESE CONDITIONS WILL LIKELY CONTINUE INTO WEDNESDAY IN
ADVANCE OF A COLD FRONT. THE SOUTHERN BAYS MAY FLIRT WITH SMALL
CRAFT ADVISORY CONDITIONS TODAY BUT CONFIDENCE IS NOT HIGH ENOUGH
TO ISSUE AN SCA AT THIS TIME. REGARDING THE RIP CURRENT RISK...
SWELLS APPEAR TO BE FINALLY LOWERING A BIT...BUT THE STRONG
ONSHORE FLOW THAT IS EXPECTED WARRANT CONTINUING THE RIP CURRENT
STATEMENT FOR NOW. IF CONDITIONS IMPROVE...THEN LATER SHIFTS MAY
CANCEL EARLY.
LONG TERM (WEDNESDAY NIGHT THROUGH MONDAY)...MODELS CONTINUE TO BE
IN AGREEMENT WITH BRINGING A COLD FRONT THROUGH S TX ON THU...WITH
SUBTLE DIFFERENCES IN TIMING AND STRENGTH. WED NIGHT AHD OF THE
FRONT...MODELS PROG PWATS OF AROUND 2 INCHES ACROSS S TX. THIS DEEP
MOISTURE IS PROGD TO COMBINE WITH AN UPPER LEVEL SHORT WAVE TO
PRODUCE SCT TO NUM SHRA/TSRAS ACROSS THE NRN PORTIONS OF THE CWA.
THE CAPPING INVERSION WILL BE TOO STRONG ACROSS THE SRN CWA WED
NIGHT...HOWEVER AM STILL EXPECTING ISOLD PRECIP DUE TO ABUNDANT
MOISTURE ABV THE INVERSION. THE COLD FRONT IS PROGD TO BE PUSHING
ACROSS THE NRN CWA BTWN 15-18Z THU. THE VCT CROSSROADS HAS THE
HIGHEST POPS DUE TO LITTLE TO NO CAP...HIGHEST CAPE AND PROXIMITY TO
THE RRQ OF THE UPPER LEVEL JET. IN ADDITION...MODELS SHOW STRONGEST
LOW LEVEL CONVERGENCE ACROSS THE NE CWA. STRONGEST DYNAMICS LOOK TO
BE NE OF THE CWA (ACROSS EAST TX AND LA AND EXTENDING NE) WHERE THE
STORMS PREDICTION CENTER HAS PLACED A SLIGHT RISK FOR DAY 3. THE NE
CWA COULD BE ON THE TAIL END OF THE STRONGER STORMS WITH THE
POSSIBILITY OF ISOLD SVR. GIVEN THE ABUNDANT DEEP MOISTURE AND
FORCING ALONG THE FRONT...HVY RAIN IS ALSO EXPECTED ACROSS THE NE
CWA...HOWEVER THE FRONT IS PROGD TO MOVE FAIRLY QUICKLY RESULTING IN
TOTAL RAINFALL AMOUNTS LESS THAN 2 INCHES FOR THE EVENT. ISOLD
AMOUNTS COULD BE 2-2.5 INCHES. MAIN CONCERN WOULD BE IF THE FRONT
SLOWS OR STALLS SOMEWHERE BETWEEN VCT TO CRP...THEN RAINFALL AMOUNTS
COULD BE MUCH HIGHER INTO THU EVENING DURING HALLOWEEN FESTIVITIES.
TSRA CHCS ARE LOWER TO THE W DUE TO STRONGER CAP AND WEAKER OVERALL
DYNAMICS...BUT STILL SHOULD BE SCT WITH RAINFALL AMOUNTS TOTALING
0.5-1 INCH. AS THE FRONT MOVES SE...SO WILL THE CONVECTION BUT THE
HIGHEST POPS ARE EXPECTED TO SHIFT OFFSHORE BY THU EVENING...IF THE
FRONT DOES NOT SLOW DOWN. RAIN CHANCES DIMINISH FROM NW TO SE
THROUGH THU NIGHT WITH RESIDUAL ELEVATED -SHRAS BRIEFLY BEHIND THE
FRONT. DRIER AND SLIGHTLY COOLER CONDITIONS WILL FILTER INTO S TX ON
FRI WITH REINFORCING HIGH PRESSURE MVG INTO THE AREA FRI NIGHT. THIS
WILL LEAD TO CLRG SKIES AND MILD MORE SEASONABLE TEMPS THROUGH THE
WEEKEND. RAIN CHCS BEGIN TO INCREASE ONCE AGAIN BY NEXT MONDAY WITH
RETURN FLOW.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 87 75 87 76 86 / 10 20 30 30 50
VICTORIA 87 73 84 72 82 / 10 20 70 60 70
LAREDO 92 76 93 77 90 / 10 10 20 20 40
ALICE 89 73 89 74 87 / 10 20 30 30 40
ROCKPORT 86 76 84 76 85 / 10 20 40 40 70
COTULLA 90 74 88 72 85 / 10 10 30 40 40
KINGSVILLE 89 75 90 76 87 / 10 20 30 30 40
NAVY CORPUS 85 77 86 78 84 / 10 20 30 30 40
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...RIP CURRENT RISK THROUGH LATE TONIGHT FOR THE FOLLOWING ZONES:
ARANSAS...CALHOUN...KLEBERG...NUECES.
GM...SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 7 PM CDT
WEDNESDAY FOR THE FOLLOWING ZONES: COASTAL WATERS FROM
BAFFIN BAY TO PORT ARANSAS OUT 20 NM...COASTAL WATERS FROM
PORT ARANSAS TO MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60 NM...WATERS
FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL FROM 20 TO 60
NM.
&&
$$
TB/78...AVIATION
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
432 AM CDT TUE OCT 29 2013
.SHORT TERM (TODAY THROUGH WEDNESDAY)...DEEP SOUTHERLY FLOW
THROUGH THE LOWER PARTS OF THE ATMOSPHERE WILL BRING MOISTURE BACK
INTO SOUTH TEXAS DURING THE SHORT TERM. STRATUS HAS DEVELOPED
ACROSS MUCH OF SOUTH TEXAS OVERNIGHT BUT ANTICIPATE THE LOW
CLOUDS TO MIX OUT LATER THIS MORNING. LATEST RUN HRRR PICKING UP
ON SOME SHOWER ACTIVITY THROUGH THE MORNING AND HAVE INCLUDED A 10
POP WITH MENTION OF SHOWERS THROUGH 18Z. UPPER LOW OVER THE
WESTERN CONUS WILL SLOWLY MOVE TO THE EAST TODAY...INTO FOUR
CORNERS REGION ON WEDNESDAY. PRESSURE GRADIENT WILL STRENGTHEN
OVER SOUTH TEXAS TODAY WITH SOUTHEASTERLY WINDS INCREASING BY THE
AFTERNOON. SOME GUSTS AROUND 30 MPH WILL BE POSSIBLE ACROSS THE
COASTAL BEND AND OVER THE RIO GRANDE PLAINS. HIGH TEMPS TODAY WILL
AGAIN BE ABOVE NORMAL WITH UPPER 80S ACROSS EASTERN SECTIONS TO
LOWER 90S OUT WEST. ON WEDNESDAY...DEEPER MOISTURE WILL GET DRAWN
INTO SOUTH TEXAS AS LOW LEVEL FLOW REMAINS OUT OF THE SE AND SSE.
PW VALUES WILL CLIMB TO NEAR 2 INCHES (2.1 INCHES IF THE GFS
VERIFIES) AS DISTURBANCE SCOOTS TO THE NORTH OF THE AREA. HIGHEST
CHANCES FOR SHOWERS AND STORMS ON WEDNESDAY WILL EXIST ACROSS THE
NORTHEAST ZONES WHERE CAPPING WILL BE THE WEAKEST. POPS RANGE FROM
SLIGHT CHANCE OVER THE SOUTHWEST ZONES TO LIKELY IN THE NORTHEAST
SECTIONS. TEMPS ON WEDNESDAY WILL BE SIMILAR TO TODAY...EXCEPT
OVER THE NORTHEAST WHERE BETTER RAIN CHANCES AND CLOUD COVER MAY
KEEP TEMPS DOWN A FEW DEGREES. YET ANOTHER BREEZY TO WINDY DAY ON
WEDNESDAY IN ADVANCE OF THURSDAY/S FROPA.
&&
.MARINE/COASTAL...ONSHORE FLOW BEGIN TO INCREASE ACROSS THE GULF
WATERS TODAY AS GRADIENT STRENGTHENS OVER THE AREA. SMALL CRAFT
ADVISORY CONDITIONS WILL DEVELOP THIS EVENING WITH WINDS OF 20 TO
25 KNOTS. IN ADDITION...SEAS WILL CLIMB TO 7 TO 8 FEET OVER THE
WATERS. THESE CONDITIONS WILL LIKELY CONTINUE INTO WEDNESDAY IN
ADVANCE OF A COLD FRONT. THE SOUTHERN BAYS MAY FLIRT WITH SMALL
CRAFT ADVISORY CONDITIONS TODAY BUT CONFIDENCE IS NOT HIGH ENOUGH
TO ISSUE AN SCA AT THIS TIME. REGARDING THE RIP CURRENT RISK...
SWELLS APPEAR TO BE FINALLY LOWERING A BIT...BUT THE STRONG
ONSHORE FLOW THAT IS EXPECTED WARRANT CONTINUING THE RIP CURRENT
STATEMENT FOR NOW. IF CONDITIONS IMPROVE...THEN LATER SHIFTS MAY
CANCEL EARLY.
&&
.LONG-TERM (WEDNESDAY NIGHT THROUGH MONDAY)...MODELS CONTINUE TO BE
IN AGREEMENT WITH BRINGING A COLD FRONT THROUGH S TX ON THU...WITH
SUBTLE DIFFERENCES IN TIMING AND STRENGTH. WED NIGHT AHD OF THE
FRONT...MODELS PROG PWATS OF AROUND 2 INCHES ACROSS S TX. THIS DEEP
MOISTURE IS PROGD TO COMBINE WITH AN UPPER LEVEL SHORT WAVE TO
PRODUCE SCT TO NUM SHRA/TSRAS ACROSS THE NRN PORTIONS OF THE CWA.
THE CAPPING INVERSION WILL BE TOO STRONG ACROSS THE SRN CWA WED
NIGHT...HOWEVER AM STILL EXPECTING ISOLD PRECIP DUE TO ABUNDANT
MOISTURE ABV THE INVERSION. THE COLD FRONT IS PROGD TO BE PUSHING
ACROSS THE NRN CWA BTWN 15-18Z THU. THE VCT CROSSROADS HAS THE
HIGHEST POPS DUE TO LITTLE TO NO CAP...HIGHEST CAPE AND PROXIMITY TO
THE RRQ OF THE UPPER LEVEL JET. IN ADDITION...MODELS SHOW STRONGEST
LOW LEVEL CONVERGENCE ACROSS THE NE CWA. STRONGEST DYNAMICS LOOK TO
BE NE OF THE CWA (ACROSS EAST TX AND LA AND EXTENDING NE) WHERE THE
STORMS PREDICTION CENTER HAS PLACED A SLIGHT RISK FOR DAY 3. THE NE
CWA COULD BE ON THE TAIL END OF THE STRONGER STORMS WITH THE
POSSIBILITY OF ISOLD SVR. GIVEN THE ABUNDANT DEEP MOISTURE AND
FORCING ALONG THE FRONT...HVY RAIN IS ALSO EXPECTED ACROSS THE NE
CWA...HOWEVER THE FRONT IS PROGD TO MOVE FAIRLY QUICKLY RESULTING IN
TOTAL RAINFALL AMOUNTS LESS THAN 2 INCHES FOR THE EVENT. ISOLD
AMOUNTS COULD BE 2-2.5 INCHES. MAIN CONCERN WOULD BE IF THE FRONT
SLOWS OR STALLS SOMEWHERE BETWEEN VCT TO CRP...THEN RAINFALL AMOUNTS
COULD BE MUCH HIGHER INTO THU EVENING DURING HALLOWEEN FESTIVITIES.
TSRA CHCS ARE LOWER TO THE W DUE TO STRONGER CAP AND WEAKER OVERALL
DYNAMICS...BUT STILL SHOULD BE SCT WITH RAINFALL AMOUNTS TOTALING
0.5-1 INCH. AS THE FRONT MOVES SE...SO WILL THE CONVECTION BUT THE
HIGHEST POPS ARE EXPECTED TO SHIFT OFFSHORE BY THU EVENING...IF THE
FRONT DOES NOT SLOW DOWN. RAIN CHANCES DIMINISH FROM NW TO SE
THROUGH THU NIGHT WITH RESIDUAL ELEVATED -SHRAS BRIEFLY BEHIND THE
FRONT. DRIER AND SLIGHTLY COOLER CONDITIONS WILL FILTER INTO S TX ON
FRI WITH REINFORCING HIGH PRESSURE MVG INTO THE AREA FRI NIGHT. THIS
WILL LEAD TO CLRG SKIES AND MILD MORE SEASONABLE TEMPS THROUGH THE
WEEKEND. RAIN CHCS BEGIN TO INCREASE ONCE AGAIN BY NEXT MONDAY WITH
RETURN FLOW.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 87 75 87 76 86 / 10 20 30 30 50
VICTORIA 87 73 84 72 82 / 10 20 70 60 70
LAREDO 92 76 93 77 90 / 10 10 20 20 40
ALICE 89 73 89 74 87 / 10 20 30 30 40
ROCKPORT 86 76 84 76 85 / 10 20 40 40 70
COTULLA 90 74 88 72 85 / 10 10 30 40 40
KINGSVILLE 89 75 90 76 87 / 10 20 30 30 40
NAVY CORPUS 85 77 86 78 84 / 10 20 30 30 40
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...RIP CURRENT RISK THROUGH LATE TONIGHT FOR THE FOLLOWING ZONES:
ARANSAS...CALHOUN...KLEBERG...NUECES.
GM...SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 7 PM CDT
WEDNESDAY FOR THE FOLLOWING ZONES: COASTAL WATERS FROM
BAFFIN BAY TO PORT ARANSAS OUT 20 NM...COASTAL WATERS FROM
PORT ARANSAS TO MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60 NM...WATERS
FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL FROM 20 TO 60
NM.
&&
$$
TB/78...SHORT TERM
TE/81...LONG TERM
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1132 PM CDT MON OCT 28 2013
.DISCUSSION...
SEE AVIATION FOR THE 06Z TAF DISCUSSION.
&&
.AVIATION...
AT 04Z MVFR CIGS WERE DEVELOPING ACROSS SOUTH CENTRAL TEXAS...HAVING
REACHED KSAT AND KSSF. MVFR CIGS WILL REACH KAUS BY 07Z AND KDRT
BY 08Z. CONDITIONS WILL DETERIORATE TO IFR BETWEEN 10Z AND 11Z. CIGS
WILL GRADUALLY IMPROVE TO MVFR BY 17Z...VFR BY 19Z. THE PREVAILING
S TO SE FLOW OFF THE GULF WILL ALLOW MVFR CIGS TO RETURN BY 30/04Z.
SFC WINDS OVERNIGHT SE AT 5 TO 8 KTS...10 TO 15 KTS TUESDAY AFTERNOON.
WILL NOT MENTION CONVECTION IN THE TAFS ATTM FOR TUESDAY AFTERNOON
AND EVENING DUE TO UNCERTAINTY IN TIMING.
&&
.PREV DISCUSSION... /ISSUED 628 PM CDT MON OCT 28 2013/
DISCUSSION...
SEE AVIATION FOR THE 00Z TAF DISCUSSION.
AVIATION...
A MODERATE S TO SE FLOW IN THE BOUNDARY LAYER WILL RESULT IN THE
EARLY ONSET OF MVFR CIGS THIS EVENING. THIS WILL INHIBIT SIGNIFICANT
FOG FORMATION...WITH PATCHY VSBYS REMAINING AOA 1 MILE IN AREAS
THAT EXPERIENCE DELAYED LOW CLOUD DEVELOPMENT. THERE ARE SOME
TIMING DIFFERENCES BETWEEN THE 12Z HIRES-ARW AND THE 21Z RUC13 IN
REGARDS TO THE FORMATION OF MVFR CIGS TONIGHT. WILL LEAN TOWARDS A
BLEND OF THE SLOWER RUC13 AND LATEST LAMP MOS GUIDANCE.
I-35 TERMINALS...MVFR CIGS WILL FORM BETWEEN 04Z AND 06Z...LOWERING
TO IFR BY 11Z. CIGS IMPROVE TO MVFR BY 15Z...VFR BY 17Z. SFC WINDS
OVERNIGHT SE AT 5 TO 8 KTS...SE 10 TO 15 KTS TUESDAY AFTERNOON.
KDRT TERMINAL...MVFR CIGS FORM AROUND 07Z LOWERING TO IFR BY 10Z.
CIGS IMPROVE TO MVFR BY 16Z...VFR BY 20Z. SFC WINDS OVERNIGHT SE
AT 5 TO 10 KTS...AROUND 15 KTS TUESDAY AFTERNOON.
PREV DISCUSSION... /ISSUED 323 PM CDT MON OCT 28 2013/
SHORT TERM (TONIGHT THROUGH TUESDAY NIGHT)...
WARM SOUTHERLY FLOW IN THE BOUNDARY LAYER AND PACIFIC MOISTURE
STREAMING INTO THE AREA IN THE UPPER LEVELS WILL RESULT IN ANOTHER
HUMID AND CLOUDY NIGHT. SFC PRESSURE GRADIENTS APPEAR TO REMAIN
TOO TIGHT TO PROMOTE WIDESPREAD DEVELOPMENT OF FOG...BUT COULD SEE
PATCHY FOG DEVELOP IN THE NEAR-SUNRISE HOURS ACROSS EASTERN
PORTIONS OF THE REGION. AN UPPER LEVEL LOW ACROSS THE WESTERN U.S.
WILL PUSH EASTWARD TOWARD THE ROCKIES ON TUESDAY. THIS WILL
ENHANCE THE SOUTHEASTERLY FLOW ACROSS OUR AREA AND RESULT IN
ANOTHER PARTLY TO MOSTLY CLOUDY AND UNSEASONABLY WARM AFTERNOON.
DEEPENING MOISTURE THROUGH THE LOWER LEVELS AND INCREASING
INSTABILITY AS THE UPPER LOW APPROACHES WILL LEAD TO ISOLATED
SHOWERS AND THUNDERSTORMS DEVELOPING ACROSS THE HILL COUNTRY
TUESDAY AFTERNOON. AN INCREASE IN AREAL COVERAGE IS EXPECTED
TUESDAY NIGHT. OTHERWISE...THE CLOUDY MUGGY AND MILD PATTERN WILL
PERSIST TUESDAY NIGHT WITH LOWS REMAINING MOSTLY NEAR 70.
LONG TERM (WEDNESDAY THROUGH MONDAY)...
AS THE UPPER LOW CONTINUES TO PUSH EASTWARD INTO THE CENTRAL
PLAINS...IT WILL TRANSITION TO AN OPEN WAVE/TROUGH. A COLD FRONT
WILL DEVELOP WITH THIS SYSTEM AND DIG INTO TEXAS ON THURSDAY.
AHEAD OF THE PASSAGE OF THE FRONT...CHANCES FOR SHOWERS AND
THUNDERSTORMS WILL INCREASE DRAMATICALLY ON WEDNESDAY AND
WEDNESDAY NIGHT BEFORE TAPERING OFF THURSDAY AFTERNOON WITH THE
FROPA. MODELS ARE PROJECTING PW VALUES TO SURGE TO ABOVE 2 INCHES
ACROSS EASTERN PORTIONS OF THE REGION BY WEDNESDAY (NORMAL PWS FOR
LATE OCTOBER ARE GENERALLY 1.25 TO 1.5 INCHES). GIVEN OUR POSITION
IN THE WARM SECTOR AHEAD OF THE FRONT AND THE AMPLE MOISTURE...THERE
IS A THREAT FOR LOCALLY HEAVY RAINFALL WITH THESE STORMS. RAINFALL
TOTALS ARE EXPECTED TO AVERAGE ONE TO THREE INCHES...WITH ISOLATED
TOTALS OF 5 INCHES OR MORE POSSIBLE. A FLASH FLOOD WATCH MAY BE
NECESSARY.
THE COLD FRONT WILL REACH THE COAST LATE THURSDAY AFTERNOON AND
DRIER AIR WILL BEGIN TO FILTER INTO THE REGION THURSDAY NIGHT.
THURSDAY EVENING WILL BE MILD WITH A LIGHT NORTHERLY WIND.
TEMPERATURES WILL FALL TO THE UPPER 60S ACROSS MUCH OF THE REGION
(LOW 60S HILL COUNTRY) BY 9 PM. THE DRIER AIR ENTERING THE REGION
WILL BEGIN TO CLEAR OUT SKIES FROM NORTH TO SOUTH THURSDAY NIGHT.
LOW TEMPERATURES FRIDAY MORNING WILL RANGE FROM THE MID 40S ACROSS
THE HILL COUNTRY TO NEAR 60 ACROSS OUR SOUTHERN COUNTIES.
UPPER LEVEL FLOW WILL BE NORTHWESTERLY ON FRIDAY AND FLATTEN-OUT
OVER THE WEEKEND. THIS WILL KEEP A DRY AIRMASS OVER OUR AREA AND
RESULT IN CHILLY MORNINGS AND WARM AFTERNOONS. SOUTHEASTERLY WINDS
WILL RETURN IN THE LOWER LEVELS ON SUNDAY LEADING TO A RAPID
WARMING TREND OF OVERNIGHT LOWS DURING THE BEGINNING OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 70 84 70 82 71 / - 10 30 60 70
AUSTIN BERGSTROM INTL AIRPORT 67 84 70 80 71 / - 10 30 60 70
NEW BRAUNFELS MUNI AIRPORT 68 85 71 82 70 / - 10 30 50 70
BURNET MUNI AIRPORT 67 81 67 78 66 / - 10 30 70 70
DEL RIO INTL AIRPORT 70 83 71 83 65 / - 20 30 30 30
GEORGETOWN MUNI AIRPORT 67 82 68 81 68 / - 10 30 70 70
HONDO MUNI AIRPORT 72 87 73 85 70 / - 10 30 50 50
SAN MARCOS MUNI AIRPORT 67 84 70 81 70 / - 10 30 60 70
LA GRANGE - FAYETTE REGIONAL 70 87 73 83 74 / - 10 20 50 70
SAN ANTONIO INTL AIRPORT 72 86 73 83 71 / - 10 30 50 60
STINSON MUNI AIRPORT 72 88 73 85 73 / - 10 30 50 60
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...13
SYNOPTIC/GRIDS...04
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
139 PM EDT TUE OCT 29 2013
.SYNOPSIS...
A WEAK FRONT EXTENDED FROM VIRGINIA TO A LOW IN KANSAS
MISSOURI...WHILE HIGH PRESSURE COVERED THE NORTHERN PLAINS TO THE
GREAT LAKES. TUESDAY AND WEDNESDAY THE LOW WILL DEEPEN OVER THE
CENTRAL PLAINS AND MOVE SLOWLY NORTHEAST. BY FRIDAY THE LOW WILL
BE OVER THE GREAT LAKES AND A STRONG COLD FRONT WILL MOVE ACROSS
THE EASTERN UNITED STATES.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 100 PM EDT TUESDAY...
DECREASED CLOUD COVER AND POPS FOR THIS AFTERNOON INTO TONIGHT.
ADJUSTED TEMPERATURES FOR THE LESS CLOUD COVER.
AS OF 915 AM EDT TUESDAY...
LOW CLOUDS AND FOG WILL SLOWLY LIFT OR ERODE WITH MIXING AND
HEATING THIS MORNING. THIS MORNING 12Z/8AM RNK SOUNDING SHOWED
LOW LEVEL MOISTURE UP TO 850 MB WITH THE NORTHWEST FLOW JUST ABOVE
THE SURFACE. HRRR AND RNK WRFARW INDICATED LIGHT RAIN DEVELOP
AFTER 18Z THIS AFTERNOON. DECIDED TO CUT BACK ON MORNING POPS
INTO THIS AFTERNOON. WILL ALLOW FOR SOME ISOLATED RAIN MAINLY
ALONG AND WEST OF I77 THIS AFTERNOON INTO TONIGHT. MODIFIED
TEMPERATURES...DEW POINTS AND CLOUD COVER WITH LATEST OBS TRENDS
FOR THIS MORNING. MORE CHANGES LATER TODAY...
AS OF 345 AM EDT TUESDAY...
A WEAK STATIONARY BOUNDARY ALONG THE NORTHERN EDGE OF AN AIR MASS
WITH HIGHER SURFACE DEW POINTS. SCATTERED RAIN NORTH OF BLUEFIELD
AND ROANOKE EARLY THIS MORNING WAS MOVING EAST AND DISSIPATING. DO
NOT THINK THE PROBABILITY OF RAIN WILL COMPLETELY GO AWAY BUT JUST
BE AT A MINIMUM TODAY.
BY THIS EVENING ANOTHER SHORT WAVE TRACKING ALONG THE NORTHERN
FRINGE OF BUILDING UPPER RIDGE WILL BE REACHING THE WESTERN COUNTY
WARNING AREA. MODELS WERE ALSO SHOWING BETTER ISENTROPIC LIFT
TONIGHT AROUND THE 290K LEVEL. EXPECT PROBABILITY OF PRECIPITATION
TO INCREASE AND GRADUALLY MOVE EAST OVERNIGHT.
WITH ALL THE CLOUD COVER TODAY...AGAIN WENT COOLER THAN GUIDANCE FOR
MAXIMUM TEMPERATURES IN THE MOUNTAINS TODAY. GUIDANCE FOR MONDAY WAS
TOO WARM IN THIS AREA. EAST OF THE BLUE RIDGE USED A BLEND OF BIAS
CORRECTED ADJMET/ADJMAV NUMBERS.
850 MB START OUT FROM THE WEST TODAY AND EVENTUALLY BECOME SOUTH
TONIGHT. WITH WEAK WARM ADVECTION AND ABUNDANT CLOUD
COVER...TEMPERATURES WILL HAVE A LIMITED DROP OVERNIGHT...ESPECIALLY
ALONG THE RIDGES. STAYED CLOSER TO WARMER MET GUIDANCE FOR MINIMUM
TEMPERATURES.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
AS OF 330 AM EDT TUESDAY...
FOR WEDNESDAY...MODELS ARE IN BETTER AGREEMENT THIS MORNING THAT WE
WILL START THE DAY OFF WITH A WARM FRONT SITUATED NEAR THE
INTERSTATE 64 CORRIDOR. MINOR DISTURBANCES RIDING ALONG THE BOUNDARY
FROM THE WEST WILL PASS ACROSS OUR AREA DURING THE MORNING AND EARLY
AFTERNOON...TRIGGERING SPOTTY SHOWERS GENERALLY WITH LIGHT RAINFALL
AMOUNTS. THE FRONT WILL LIFT NORTH THROUGH THE DAY...LEAVING THE MID
ATLANTIC SITUATED IN AN AREA OF STRONG SOUTHWESTERLY WINDFLOW.
RISING 500MB HEIGHTS AS AN UPPER LEVEL RIDGE BUILDS IN FROM THE WEST
WILL ALLOW THE WARMUP TO CONTINUE...AS AFTERNOON HIGHS RANGE FROM
THE MID/UPPER 60S ACROSS THE MOUNTAINS...TO THE LOW 7OS FURTHER
EAST.
SHOWER ACTIVITY WILL INCREASE ON THURSDAY AS A DEEP LOW PRESSURE
SYSTEM PASSES ACROSS THE WESTERN GREAT LAKES...DRAGGING A STRONG
COLD FRONT EAST FROM THE MISSISSIPPI RIVER VALLEY. STUCK CLOSER TO
THE NAM/ECMWF/CANADIAN MODEL SOLUTIONS RELATIVE TO TIMING OF THE
MORE WIDESPREAD SHOWER ACTIVITY...ALL OF WHICH FAVOR HEAVIER
RAINFALL ENTERING THE MOUNTAINS DURING THE EVENING. THE UPPER RIDGE
AXIS IS EXPECTED TO BE SITUATED ALONG THE APPALACHIAN CHAIN THURSDAY
AFTERNOON...AND WHEN FACTORING IN A DELAYED ONSET TO WIDESPREAD
RAINFALL...BELIEVE THAT THURSDAY WILL BE THE WARMEST DAY FOR MOST
AREAS...LIKELY ONLY A DEGREE OR TWO OVER WEDNESDAY`S HIGHS HOWEVER.
SHOWER ACTIVITY IS EXPECTED TO BECOME WIDESPREAD DURING THE EARLY
HOURS OF FRIDAY. MODELS CONTINUE TO SUGGEST LOW CAPE/INSTABILITY AS
THE SUPPORTING UPPER LEVEL TROUGH MOVES ACROSS FROM THE WEST...BUT
VERY HIGH SHEAR AND HELICITY AS A 50KT TO 60KT LOW LEVEL JET
DEVELOPS. BELIEVE THESE CONDITIONS WILL SUPPORT MAINLY STRONG
SHOWERS WITH ONLY MINIMAL LIGHTNING...BUT THAT THE STRONGER SHOWERS
WILL BE CAPABLE OF DRAWING SOME OF THE STRONGER WINDS ALOFT DOWN TO
THE SURFACE...RESULTING IN GUSTY AND LOCALLY DAMAGING WINDS. THE
HIGH SHEAR AND HELICITY ALSO MEAN THAT ISOLATED AND SHORT LIVED
TORNADOES WILL BE POSSIBLE. AREAS ALONG AND EAST OF THE BLUE RIDGE
WILL HAVE A BETTER THREAT FOR SEVERE WEATHER...AS THE SMOOTHER
TERRAIN WILL ALLOW FOR BETTER ORGANIZATION OF CONVECTION. IN
ADDITION...IF TIMING OF THE UPPER TROUGH IS DELAYED ANY...DAYTIME
HEATING MAY ENHANCE THE CONVECTION ACROSS THE PIEDMONTS.
HEAVIEST RAINFALL WILL MOVE EAST OF OUR AREA BY EARLY AFTERNOON ON
FRIDAY...WITH LINGERING SHOWER ACTIVITY EXPECTED THROUGH EVENING.
MILD AIR WILL REMAIN OVER OUR AREA THROUGH FRIDAY NIGHT...WITH THE
TRULY COLDER AIR NOT EXPECTED TO ARRIVE UNTIL AFTER SUNRISE
SATURDAY.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 100 PM EDT MONDAY...
ON SATURDAY...WINDS WILL BECOME INCREASINGLY NORTHWESTERLY IN THE
WAKE OF THE DEPARTING COLD FRONT. THIS WILL ALLOW FOR GOOD DOWNSLOPE
CLEARING OF SKIES EAST OF THE CREST OF THE BLUE RIDGE. ACROSS THE
MOUNTAINS...THE FLOW WILL BE UPSLOPE AND EXPECT THE DEVELOPMENT OF
THE RAIN/SNOW SHOWERS ACROSS THE PREFERRED UPSLOPE REGIONS OF MAINLY
SOUTHEAST WEST VIRGINIA...ACCOMPANYING COUNTIES OF SOUTHWEST
VIRGINIA...AND THE NORTHERN MOUNTAINS OF THE NORTH CAROLINA.
FLURRIES OR SPRINKLES WILL CARRY DOWNSTREAM OF THE MAIN ACTIVITY TO
AROUND THE CREST OF THE BLUE RIDGE AND THE NORTH CAROLINA FOOTHILLS.
THIS PATTERN WILL CONTINUE THROUGH AT LEAST SUNDAY...WITH GRADUALLY
DECREASING COVERAGE OF THE SHOWER ACTIVITY AS 850 MB WINDS WEAKEN
AND VEER NORTH TO NORTHEAST.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 137 PM EDT TUESDAY...
SCT TO BKN MVFR CLOUDS THIS AFTERNOON INTO TONIGHT. ANOTHER
SHORTWAVE TRACKS NORTH OF THE UPPER RIDGE AND REACHES THE CENTRAL
APPALACHIANS TONIGHT. TAF SITES IN THE MOUNTAINS WILL LOWER TO
MVFR AFTER 05Z/1AM WITH THIS SHORTWAVE. OVERNIGHT INTO WEDNESDAY
MORNING EXPECTED MVFR CEILING WITH POCKETS OF IFR IN LOW
CLOUDS...FOG AND LIGHT RAIN.
MEDIUM CONFIDENCE IN CIGS THROUGH TAF PERIOD.
MEDIUM CONFIDENCE IN VSBYS THROUGH TAF VALID PERIOD.
HIGH CONFIDENCE IN WIND SPD/DIR THROUGH TAF VALID PERIOD.
MVFR-VFR CONDITIONS ARE EXPECTED WEDNESDAY AND THURSDAY WITH
EXTENSIVE MID/HIGH CLOUDS. CANNOT RULE OUT OCCASIONAL -SHRA IN
ADVANCE OF A STRONG FRONT THURSDAY...BUT THE MAIN BAND OF
PRECIPITATION WILL COME THURSDAY NIGHT/FRIDAY WITH HEAVY
RAIN SHOWERS AND GUSTY WINDS AND POTENTIAL FOR LOW-LEVEL WIND
SHEAR. THIS WILL BRING AT LEAST BRIEF PERIODS OF IFR CIGS/VSYBS AS
WELL.
IN THE WAKE OF THE COLD FRONT...LOOK FOR INCREASING NORTHWEST
FLOW BEHIND THE SURFACE SYSTEM. THIS WILL RESULT IN UPSLOPE
RAIN/SNOW SHOWERS ACROSS THE PREFERRED UPSLOPE REGIONS OF
SOUTHEAST WEST VIRGINIA SATURDAY INTO SUNDAY ALONG WITH IFR-MVFR
CEILINGS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/KK
SHORT TERM...NF
LONG TERM...DS
AVIATION...AMS/KK
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
925 AM EDT TUE OCT 29 2013
.SYNOPSIS...
A WEAK FRONT EXTENDED FROM VIRGINIA TO A LOW IN KANSAS
MISSOURI...WHILE HIGH PRESSURE COVERED THE NORTHERN PLAINS TO THE
GREAT LAKES. TUESDAY AND WEDNESDAY THE LOW WILL DEEPEN OVER THE
CENTRAL PLAINS AND MOVE SLOWLY NORTHEAST. BY FRIDAY THE LOW WILL
BE OVER THE GREAT LAKES AND A STRONG COLD FRONT WILL MOVE ACROSS
THE EASTERN UNITED STATES.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 915 AM EDT TUESDAY...
LOW CLOUDS AND FOG WILL SLOWLY LIFT OR ERODE WITH MIXING AND
HEATING THIS MORNING. THIS MORNING 12Z/8AM RNK SOUNDING SHOWED
LOW LEVEL MOISTURE UP TO 850 MB WITH THE NORTHWEST FLOW JUST ABOVE
THE SURFACE. HRRR AND RNK WRFARW INDICATED LIGHT RAIN DEVELOP
AFTER 18Z THIS AFTERNOON. DECIDED TO CUT BACK ON MORNING POPS
INTO THIS AFTERNOON. WILL ALLOW FOR SOME ISOLATED RAIN MAINLY
ALONG AND WEST OF I77 THIS AFTERNOON INTO TONIGHT. MODIFIED
TEMPERATURES...DEW POINTS AND CLOUD COVER WITH LATEST OBS TRENDS
FOR THIS MORNING. MORE CHANGES LATER TODAY...
AS OF 345 AM EDT TUESDAY...
A WEAK STATIONARY BOUNDARY ALONG THE NORTHERN EDGE OF AN AIR MASS
WITH HIGHER SURFACE DEW POINTS. SCATTERED RAIN NORTH OF BLUEFIELD
AND ROANOKE EARLY THIS MORNING WAS MOVING EAST AND DISSIPATING. DO
NOT THINK THE PROBABILITY OF RAIN WILL COMPLETELY GO AWAY BUT JUST
BE AT A MINIMUM TODAY.
BY THIS EVENING ANOTHER SHORT WAVE TRACKING ALONG THE NORTHERN
FRINGE OF BUILDING UPPER RIDGE WILL BE REACHING THE WESTERN COUNTY
WARNING AREA. MODELS WERE ALSO SHOWING BETTER ISENTROPIC LIFT
TONIGHT AROUND THE 290K LEVEL. EXPECT PROBABILITY OF PRECIPITATION
TO INCREASE AND GRADUALLY MOVE EAST OVERNIGHT.
WITH ALL THE CLOUD COVER TODAY...AGAIN WENT COOLER THAN GUIDANCE FOR
MAXIMUM TEMPERATURES IN THE MOUNTAINS TODAY. GUIDANCE FOR MONDAY WAS
TOO WARM IN THIS AREA. EAST OF THE BLUE RIDGE USED A BLEND OF BIAS
CORRECTED ADJMET/ADJMAV NUMBERS.
850 MB START OUT FROM THE WEST TODAY AND EVENTUALLY BECOME SOUTH
TONIGHT. WITH WEAK WARM ADVECTION AND ABUNDANT CLOUD
COVER...TEMPERATURES WILL HAVE A LIMITED DROP OVERNIGHT...ESPECIALLY
ALONG THE RIDGES. STAYED CLOSER TO WARMER MET GUIDANCE FOR MINIMUM
TEMPERATURES.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
AS OF 330 AM EDT TUESDAY...
FOR WEDNESDAY...MODELS ARE IN BETTER AGREEMENT THIS MORNING THAT WE
WILL START THE DAY OFF WITH A WARM FRONT SITUATED NEAR THE
INTERSTATE 64 CORRIDOR. MINOR DISTURBANCES RIDING ALONG THE BOUNDARY
FROM THE WEST WILL PASS ACROSS OUR AREA DURING THE MORNING AND EARLY
AFTERNOON...TRIGGERING SPOTTY SHOWERS GENERALLY WITH LIGHT RAINFALL
AMOUNTS. THE FRONT WILL LIFT NORTH THROUGH THE DAY...LEAVING THE MID
ATLANTIC SITUATED IN AN AREA OF STRONG SOUTHWESTERLY WINDFLOW.
RISING 500MB HEIGHTS AS AN UPPER LEVEL RIDGE BUILDS IN FROM THE WEST
WILL ALLOW THE WARMUP TO CONTINUE...AS AFTERNOON HIGHS RANGE FROM
THE MID/UPPER 60S ACROSS THE MOUNTAINS...TO THE LOW 7OS FURTHER
EAST.
SHOWER ACTIVITY WILL INCREASE ON THURSDAY AS A DEEP LOW PRESSURE
SYSTEM PASSES ACROSS THE WESTERN GREAT LAKES...DRAGGING A STRONG
COLD FRONT EAST FROM THE MISSISSIPPI RIVER VALLEY. STUCK CLOSER TO
THE NAM/ECMWF/CANADIAN MODEL SOLUTIONS RELATIVE TO TIMING OF THE
MORE WIDESPREAD SHOWER ACTIVITY...ALL OF WHICH FAVOR HEAVIER
RAINFALL ENTERING THE MOUNTAINS DURING THE EVENING. THE UPPER RIDGE
AXIS IS EXPECTED TO BE SITUATED ALONG THE APPALACHIAN CHAIN THURSDAY
AFTERNOON...AND WHEN FACTORING IN A DELAYED ONSET TO WIDESPREAD
RAINFALL...BELIEVE THAT THURSDAY WILL BE THE WARMEST DAY FOR MOST
AREAS...LIKELY ONLY A DEGREE OR TWO OVER WEDNESDAY`S HIGHS HOWEVER.
SHOWER ACTIVITY IS EXPECTED TO BECOME WIDESPREAD DURING THE EARLY
HOURS OF FRIDAY. MODELS CONTINUE TO SUGGEST LOW CAPE/INSTABILITY AS
THE SUPPORTING UPPER LEVEL TROUGH MOVES ACROSS FROM THE WEST...BUT
VERY HIGH SHEAR AND HELICITY AS A 50KT TO 60KT LOW LEVEL JET
DEVELOPS. BELIEVE THESE CONDITIONS WILL SUPPORT MAINLY STRONG
SHOWERS WITH ONLY MINIMAL LIGHTNING...BUT THAT THE STRONGER SHOWERS
WILL BE CAPABLE OF DRAWING SOME OF THE STRONGER WINDS ALOFT DOWN TO
THE SURFACE...RESULTING IN GUSTY AND LOCALLY DAMAGING WINDS. THE
HIGH SHEAR AND HELICITY ALSO MEAN THAT ISOLATED AND SHORT LIVED
TORNADOES WILL BE POSSIBLE. AREAS ALONG AND EAST OF THE BLUE RIDGE
WILL HAVE A BETTER THREAT FOR SEVERE WEATHER...AS THE SMOOTHER
TERRAIN WILL ALLOW FOR BETTER ORGANIZATION OF CONVECTION. IN
ADDITION...IF TIMING OF THE UPPER TROUGH IS DELAYED ANY...DAYTIME
HEATING MAY ENHANCE THE CONVECTION ACROSS THE PIEDMONTS.
HEAVIEST RAINFALL WILL MOVE EAST OF OUR AREA BY EARLY AFTERNOON ON
FRIDAY...WITH LINGERING SHOWER ACTIVITY EXPECTED THROUGH EVENING.
MILD AIR WILL REMAIN OVER OUR AREA THROUGH FRIDAY NIGHT...WITH THE
TRULY COLDER AIR NOT EXPECTED TO ARRIVE UNTIL AFTER SUNRISE
SATURDAY.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 100 PM EDT MONDAY...
ON SATURDAY...WINDS WILL BECOME INCREASINGLY NORTHWESTERLY IN THE
WAKE OF THE DEPARTING COLD FRONT. THIS WILL ALLOW FOR GOOD DOWNSLOPE
CLEARING OF SKIES EAST OF THE CREST OF THE BLUE RIDGE. ACROSS THE
MOUNTAINS...THE FLOW WILL BE UPSLOPE AND EXPECT THE DEVELOPMENT OF
THE RAIN/SNOW SHOWERS ACROSS THE PREFERRED UPSLOPE REGIONS OF MAINLY
SOUTHEAST WEST VIRGINIA...ACCOMPANYING COUNTIES OF SOUTHWEST
VIRGINIA...AND THE NORTHERN MOUNTAINS OF THE NORTH CAROLINA.
FLURRIES OR SPRINKLES WILL CARRY DOWNSTREAM OF THE MAIN ACTIVITY TO
AROUND THE CREST OF THE BLUE RIDGE AND THE NORTH CAROLINA FOOTHILLS.
THIS PATTERN WILL CONTINUE THROUGH AT LEAST SUNDAY...WITH GRADUALLY
DECREASING COVERAGE OF THE SHOWER ACTIVITY AS 850 MB WINDS WEAKEN
AND VEER NORTH TO NORTHEAST.
&&
.AVIATION /13Z TUESDAY THROUGH SATURDAY/...
AS OF 730 AM EDT TUESDAY...
COMBINATION OF WEAK UPSLOPE LOW LEVEL WINDS AND A WEAK SURFACE
BOUNDARY ACROSS WEST VIRGINIA AND VIRGINIA PRODUCED ENOUGH LIFT
FOR SCATTERED LIGHT RAIN OVER THE MOUNTAINS. ENOUGH LOW LEVEL
MOISTURE AND LIMITED MIXING WILL RESULT IN AREAS OF STRATUS AND
FOG THIS MORNING. HIGH CONFIDENCE OF IFR CEILINGS AND
VISIBILITIES AT KBLF/KLWB AND KBCB BEFORE THROUGH 15Z/11AM. LATEST
LAMP GUIDANCE SUGGESTED IT WOULD TAKE MOST OF THE MORNING FOR
CONDITIONS TO IMPROVE AT THESE SITES.
KROA/KLYH AND KDAN WILL BE VFR TODAY. THE WEAK FRONT PASSED SOUTH
OF KLYH AT 09Z/5AM AS INDICATED BY THE NORTH TO NORTHEAST WINDS AT
5 TO 10 KNOTS. THIS WAS ALSO REFLECTED IN THE MSAS ANALYSIS OF
LIFTED INDEX VALUES.
ANOTHER SHORT WAVE TRACKS NORTH OF THE UPPER RIDGE TODAY AND
REACHES THE CENTRAL APPALACHIANS TONIGHT. TAF SITES IN THE
MOUNTAINS WILL LOWER TO MVFR AFTER 05Z/1AM WITH THIS SHORT
WAVE. CONFIDENCE IS NOT AS HIGH WITH THE COVERAGE OF LIGHT RAIN
WITH THIS SHORT WAVE. FOR NOT HAVE ADDED R- TO THE KBCB/KLWB AND
KBLF TAF OVERNIGHT.
MVFR-VFR CONDITIONS ARE EXPECTED WEDNESDAY AND THURSDAY WITH
EXTENSIVE MID/HIGH CLOUDS. CANNOT RULE OUT OCCASIONAL -SHRA IN
ADVANCE OF A STRONG FRONT THURSDAY...BUT THE MAIN BAND OF
PRECIPITATION WILL COME THURSDAY NIGHT/FRIDAY WITH HEAVY
RAIN SHOWERS AND GUSTY WINDS AND POTENTIAL FOR LOW-LEVEL WIND
SHEAR. THIS WILL BRING AT LEAST BRIEF PERIODS OF IFR CIGS/VSYBS AS
WELL.
IN THE WAKE OF THE COLD FRONT...LOOK FOR INCREASING NORTHWEST
FLOW BEHIND THE SURFACE SYSTEM. THIS WILL RESULT IN UPSLOPE
RAIN/SNOW SHOWERS ACROSS THE PREFERRED UPSLOPE REGIONS OF
SOUTHEAST WEST VIRGINIA SATURDAY INTO SUNDAY ALONG WITH IFR-MVFR
CEILINGS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/KK
SHORT TERM...NF
LONG TERM...DS
AVIATION...AMS/RAB
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
352 PM MDT TUE OCT 29 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 345 PM MDT TUE OCT 29 2013
ANOTHER CHALLENGING FORECAST FOR TONIGHT SINCE TEMPERATURES TODAY
DID NOT WARM UP AS MUCH AS PREVIOUSLY THOUGHT. CURRENT SATELLITE
LOOP SHOWS FOG AND LOW STRATUS ARE STILL PRESENT ACROSS PORTIONS
OF EXTREME SOUTHEAST WYOMING AND MOST OF WESTERN NEBRASKA.
TEMPERATURES JUMPED INTO THE 40S WEST OF THE LARAMIE RANGE...BUT
HAVE STRUGGLED TO REACH THE MIDDLE 30S EAST OF THE LARAMIE RANGE.
MODELS AND WATER VAPOR LOOP SHOW THE NEXT UPPER LEVEL DISTURBANCE
ROUNDING THE BASE OF THE MAIN UPPER LEVEL LOW OVER THE GREAT
BASIN. THIS DISTURBANCE IS EXPECTED TO IMPACT SOUTHEAST WYOMING
AND PORTIONS OF WESTERN NEBRASKA TONIGHT RESULTING IN THE
POTENTIAL OF ANOTHER WINTRY MIX ACROSS THE HIGH PLAINS. CURRENT
SOUNDINGS HAVE STRUGGLED TO SHOW PRESENT CONDITIONS TODAY...WITH
THE NAM BUFR SOUNDINGS COMING THE CLOSEST TO INITIAL CONDITIONS.
EXPECT A PERIOD OF FREEZING FOG AND PATCHY FREEZING DRIZZLE LATE
THIS EVENING EAST OF A DOUGLAS TO CHEYENNE LINE AHEAD OF THIS
UPPER LEVEL DISTURBANCE. NAM SOUNDINGS SHOW NEAR OR SLIGHTLY BELOW
FREEZING TEMPERATURES AT THE SURFACE EAST OF THE LARAMIE RANGE
WITH NEARLY ISOTHERMAL TEMPERATURES UP TO 700MB...OR WARMING
SLIGHTLY. ONCE THE AXIS OF THIS SHORTWAVE DISTURBANCE MOVES INTO
THE AREA...EXPECT LIGHT FREEZING RAIN/SLEET/SNOW MIX TO
DEVELOP...TRENDING TOWARDS SLEET AND SNOW MIX BY EARLY WEDNESDAY
MORNING AS THE TEMPERATURES LOWER BELOW 0C ALOFT. FOR THE
MOUNTAINS AND HIGHER RIDGES...INCLUDING LARAMIE AND
CHEYENNE...LITTLE ICE OR FREEZING DRIZZLE IS EXPECTED WITH MORE OF
A RAIN/SNOW MIX INITIALLY CHANGING TO ALL SNOW. WILL HAVE TO KEEP
AN EYE ON THE I80 CORRIDOR TOWARDS THE NEBRASKA BORDER FOR SNOW
ACCUMULATIONS OVER 3 INCHES SINCE MODELS CONTINUE TO INDICATE SOME
ELEVATED INSTABILITY AS THE COLD AIR ALOFT MOVES INTO THE REGION.
IN FACT...A FEW LIGHTNING STRIKES HAVE BEEN OBSERVED WITH THIS
SHORTWAVE DISTURBANCE ACROSS SOUTHWEST COLORADO. FURTHER
NORTH...EXPECT SOME ICE AND SNOW ACCUMULATION...AND ISSUED A
WINTER WEATHER ADVISORY FOR A WINTRY MIX...NORTHEAST OF A
WHEATLAND TO ALLIANCE LINE. EXPECT ICE ACCUMULATIONS AROUND ONE
TENTH TO TWO TENTHS OF AN INCH IN THESE LOCATIONS WITH SNOW
ACCUMULATIONS WEDNESDAY MORNING UP TO AN INCH.
UPPER LEVEL DISTURBANCE QUICKLY MOVES NORTHEAST INTO THE DAKOTAS
BY LATE WEDNESDAY MORNING WITH SUBSIDENCE AND DRIER CONDITIONS
EXPECTED WEDNESDAY AFTERNOON AS WINDS SHIFT INTO THE WEST. THE
NEXT FORECAST CONCERN WILL BE STRONG WINDS WEDNESDAY NIGHT AND
THURSDAY AS THE PRESSURE GRADIENT STRENGTHENS ACROSS SOUTHEAST
WYOMING. ISSUED A HIGH WIND WATCH BEGINNING MIDNIGHT LATE
WEDNESDAY NIGHT FOR THE WIND PRONE AREAS ALONG I80 BETWEEN LARAMIE
AND CHEYENNE INCLUDING THE I80 SUMMIT...AND THE ARLINGTON EXCHANGE
WEST OF LARAMIE. GUSTS AROUND 60 MPH ARE EXPECTED IN THESE
LOCATIONS BY EARLY THURSDAY MORNING. WINDS WILL INCREASE OUT OF
THE NORTHWEST EVERYWHERE BY NOON THURSDAY AS LLVL MIXING
OCCURS...WHERE WINDS MAY GUST AS HIGH AS 50 MPH OUTSIDE OF THE
WATCH AREA. MAY NEED A WIND ADVISORY FOR PORTIONS OF NEBRASKA
THURSDAY AFTERNOON WITH MOS GUIDANCE SHOWING SUSTAINED WINDS
BETWEEN 25 TO 35 MPH. POP WILL BE BELOW 5 PERCENT ACROSS MOST OF
THE FORECAST AREA OUTSIDE OF THE MOUNTAINS ON THURSDAY...BUT
UPSLOPE FLOW WILL CONTINUE OVER THE MOUNTAINS WHERE 1 TO 3 INCHES
OF SNOW MAY ACCUMULATE IN THE SNOWY AND SIERRA MADRE RANGES.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 330 AM MDT TUE OCT 29 2013
HIGH WINDS LOOK TO BE CONTINUING THE BEGINNING OF THE LONG TERM AS
GFS SHOWING 700MB WINDS 50+ KTS OVER SOUTHERN WYOMING. WINDS WILL
BE EASING DURING THE OVERNIGHT HOURS INTO FRIDAY MORNING...DOWN TO
AROUND 35KTS BY 12Z FRIDAY.
NORTHWEST FLOW FOR FRIDAY WITH FAIRLY COOL TEMPERATURES. 700MB
TEMPERATURES -4 TO -6C SHOULD EQUATE TO 40 HIGHS OUT WEST. WITH A
DOWNSLOPING COMPONENT THOUGH...AREAS EAST OF THE LARAMIE RANGE
SHOULD MAKE IT INTO THE 50S FRIDAY AFTERNOON.
BRIEF WARM UP FOR THE WEEKEND AS 700MB TEMPERATURES CLIMB BACK
ABOVE FREEZING...UP TO +4 TO +6C SATURDAY INTO SUNDAY. LOOKING AT
VERY NICE TEMPERATURES BOTH DAYS...60S EAST OF THE LARAMIE
RANGE...50S WEST.
WARM CONDITIONS WILL BE TEMPORARY THOUGH AS OUR NEXT PACIFIC STORM
SYSTEM LOOKS TO MOVE INTO THE AREA SUNDAY NIGHT INTO MONDAY. 700MB
TEMPERATURE FALL TO -8 TO -10C MONDAY AFTERNOON AS THE FRONT MOVES
THROUGH THE AREA AND STALLS OVER NORTHERN COLORADO. BOTH THE GFS
AND ECMWF ARE IN GOOD AGREEMENT FOR WIDESPREAD PRECIP DEVELOPING
INITIALLY OUT WEST OVER CARBON COUNTY...BUT SPREADING ACROSS THE
ENTIRE CWFA BY MONDAY NIGHT. WITH THE COLD 700MB
TEMPERATURES...THIS SHOULD ALL FALL AS SNOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY MORNING)
ISSUED AT 1104 AM MDT TUE OCT 29 2013
TOUGH FORECAST FOR THE SOUTHEAST WYOMING AND NEBRASKA PANHANDLE
AIRPORTS TODAY. RELYING HEAVILY ON LATEST HRRR FORECAST THAT
BREAKS OUT CHEYENNE AND THE SOUTHERN PANHANDLE LATE THIS AFTERNOON
FOR A BRIEF TIME. FOR CHADRON AND ALLIANCE...THINK THESE AIRPORTS
WILL STAY DOWN ALL DAY. ALL AIRPORTS EAST OF THE LARAMIE RANGE
WILL GO DOWN ONCE AGAIN THIS EVENING AS UPPER LOW EJECTS SOME
ENERGY EAST. CONFIDENCE HIGH ON THIS HAPPENING. SHOULD SEE A
RETURN TO VFR CONDITIONS FROM WEST TO EAST LATE WEDNESDAY MORNING.
&&
.FIRE WEATHER...
ISSUED AT 300 PM MDT TUE OCT 29 2013
WITH WINTRY WEATHER AND COOL TEMPERATURES EXPECTED THIS WEEK...AND
AGAIN EARLY NEXT WEEK...NO FIRE WEATHER CONCERNS ARE ANTICIPATED.
TEMPERATURES WILL GRADUALLY MODERATE LATE THIS WEEK WITH
INCREASING WINDS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO NOON MDT
WEDNESDAY FOR WYZ102-107-108.
HIGH WIND WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY
AFTERNOON FOR WYZ110-116-117.
NE...WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO NOON MDT
WEDNESDAY FOR NEZ002-003-019-095-096.
&&
$$
SHORT TERM...TJT
LONG TERM...CLAYCOMB
AVIATION...CLAYCOMB
FIRE WEATHER...TJT
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1109 AM MDT TUE OCT 29 2013
.UPDATE...
ISSUED AT 951 AM MDT TUE OCT 29 2013
UPDATED FORECAST THROUGH TONIGHT WITH ONLY MINOR CHANGES TODAY.
FORECAST FOR TODAY LOOKS ON TRACK WITH FOG AND FREEZING DRIZZLE
CONTINUING LATE THIS MORNING. LOW STRATUS AND FOG IS TAKING ITS
TIME LIFTING...SO LOWERED HOURLY TEMPERATURES BY 3-5 DEGREES
THROUGH 3 PM THIS AFTERNOON. WILL CONTINUE WITH THE FREEZING RAIN
ADVISORY UNTIL NOON WITH SEVERAL REPORTS ACROSS THE AREA OBSERVING
ICE ACCUMULATIONS UP TO A QUARTER INCH FROM LARAMIE COUNTY
NORTHEAST TO NORTHWEST NEBRASKA. EXPECT FOG TO GRADUALLY LIFT THIS
AFTERNOON WITH SOME SUNSHINE EXPECTED...WHICH WILL MELT MOST OF
THE ICE INTO THIS EVENING.
ATTENTION THEN SHIFTS TO THE POTENTIAL FOR SNOW TONIGHT AS A
POTENT SHORTWAVE...CURRENTLY OVER SOUTHERN NEVADA AND
CALIFORNIA...EJECTS NORTHEASTWARD OVER SOUTHEAST WYOMING AND MAYBE
WESTERN NEBRASKA. MODELS HAVE NOT BEEN CONSISTENT WITH THE
PLACEMENT OF THIS FEATURE AND ASSOCIATED PRECIPITATION. DID
INCREASE POP TONIGHT EAST OF A LINE FROM LARAMIE TO CHADRON. THERE
IS THE POTENTIAL OF LIGHT TO MODERATE SNOW ACCUMULATIONS...BUT
SNOW LEVEL WILL BE RELATIVELY HIGH...AROUND 6000 TO 7000 FEET.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT)
ISSUED AT 345 AM MDT TUE OCT 29 2013
PREDAWN WATER VAPOR SATELLITE IMAGERY SHOWED THE PACIFIC UPPER
LOW CENTER HAD MOVED EAST INTO NORTHERN NEVADA WITH BROAD
DIFFLUENT FLOW ALOFT FROM THE FOUR CORNERS THROUGH THE CENTRAL
ROCKIES AND GREAT PLAINS. THE REGIONAL SURFACE ANALYSIS DEPICTED
A STATIONARY FRONT FROM CENTRAL IDAHO THROUGH SOUTHWEST WYOMING...
ALONG THE COLORADO FRONT RANGE TO THE SOUTH CENTRAL HIGH PLAINS.
NORTH OF THIS BOUNDARY...A SHALLOW COLD AIR MASS WAS ENTRENCHED
ACROSS THE CWA. WARM MOIST AIR OVERRUNNING THE COLD AIR ALOFT AND
UPSLOPE LOW LEVEL FLOW WAS CREATING WIDESPREAD FOG...LIGHT FREEZING
DRIZZLE AND SNOW. ICE ACCUMULATIONS HAVE BEEN LIGHT THUS FAR...BUT
ARE CAUSING HAZARDOUS DRIVING CONDITIONS DUE TO BLACK ICE. SURFACE
TEMPERATURES REMAINED STEADY IN THE 20S. VISIBILITIES IN FOG
GENERALLY RANGED FROM 1 TO 5 MILES...BUT WERE AS LOW AS A QUARTER
MILE ACROSS THE SOUTHERN LARAMIE RANGE WHERE A DENSE FOG ADVISORY
REMAINS IN EFFECT UNTIL 6 AM.
THE 00Z SHORT RANGE MODEL GUIDANCE IS IN GOOD AGREEMENT PROGGING
THE NEVADA UPPER LOW TO MOVE NORTHEAST INTO WYOMING TONIGHT AND
THE DAKOTAS ON WEDNESDAY. SYNOPTIC SCALE LIFT ASSOCIATED WITH THE
ACCOMPANYING TROUGH WILL ENHANCE THE PRECIPITATION TONIGHT AND
WEDNESDAY. FREEZING DRIZZLE MIXED WITH SNOW WILL PREVAIL THIS
MORNING EAST OF THE LARAMIE RANGE...THEN CHANGE TO RAIN OR RAIN
MIXED WITH SNOW THIS AFTERNOON AS TEMPERATURES RISE ABOVE
FREEZING. AS THE UPPER LOW MOVES INTO WYOMING TONIGHT...COLDER
AIR ALOFT WILL CHANGE THE MIXED PRECIPITATION TO SNOW. SNOW
ACCUMULATIONS WILL RANGE FROM A HALF INCH FOR THE PLAINS TO MUCH
AS 3 INCHES FOR THE SNOWY AND SIERRA MADRE RANGES. THE SNOW WILL
LINGER THROUGH WEDNESDAY NIGHT WITH AN ADDITIONAL 1 TO 3 INCHES
FOR THE SOUTHERN MOUNTAINS. LIGHT RAIN OR RAIN MIXED WITH SNOW
IS EXPECTED FOR LOWER ELEVATIONS WEDNESDAY. WEST WINDS WILL BEGIN
TO INCREASE WEDNESDAY AFTERNOON WEST OF THE LARAMIE RANGE AND
SPREAD EAST INTO SOUTHEAST WYOMING WEDNESDAY NIGHT.
TEMPERATURES DURING THE SHORT TERM PERIOD WILL AVERAGE BELOW
SEASONAL NORMALS. HIGHS TODAY WILL RANGE FROM THE 20S MOUNTAINS...
TO THE 30S TO MID 40S VALLEYS AND PLAINS. LOWS TONIGHT WILL RANGE
FROM AROUND 20 MOUNTAINS TO THE LOWER AND MID 30S PLAINS. HIGHS
WEDNESDAY WILL BE ABOUT 5 DEGREES MILDER FOR THE PLAINS WITH 40S
TO AROUND 50. LOWS WEDNESDAY NIGHT WILL BE SIMILAR TO TONIGHT/S
MINIMA.
.LONG TERM...(THURSDAY THROUGH MONDAY NIGHT)
ISSUED AT 345 AM MDT TUE OCT 29 2013
MODELS CONTINUE TO SHOW A GAP WIND EVENT SETTING UP FOR THURSDAY AS
NW FLOW ALOFT INCREASES...AND HIGH PRESSURE BUILDS IN FROM THE WEST
BOTH ALOFT AND AT THE SURFACE. THE LOW LEVEL GRADIENT WILL INCREASE
THURSDAY MORNING WITH THE APPROACHING HIGH...PROMOTING AN INCREASE
IN WESTERLY GRADIENT WINDS ACROSS THE FORECAST AREA. MID LEVEL WARM
AIR ADVECTION WILL STRENGTHEN THE INVERSION BETWEEN 600 AND 700
MB...IN ESSENCE TRAPPING THE INCREASING GRADIENT FLOW NEAR THE
SURFACE. IN THE HIGH COUNTRY...700 MB WINDS JUST BELOW THE
INVERSION LOOK TO INCREASE TO AROUND 50 KT DUE TO THE ACCELERATION
OF TRAPPED FLOW BETWEEN THE MOUNTAINS AND INVERSION. LOOKING AT
SURFACE WINDS GUSTING AROUND 60 MPH IN THESE GAP AREAS ALONG AND
WEST OF THE LARAMIE RANGE...IN ADDITION TO THE HIGHER MOUNTAIN
PEAKS THROUGH THE MORNING AND EARLY AFTERNOON UNTIL THE INVERSION
WEAKENS. GUSTS AROUND 50 MPH LOOK TO OCCUR IN THE PLAINS TO THE
IMMEDIATE EAST OF THE LARAMIE RANGE...AND WILL ALSO SEE BREEZY
CONDITIONS ELSEWHERE ACROSS WYOMING AND THE WESTERN NEBRASKA
PANHANDLE DUE TO THE GENERAL INCREASING GRADIENT FLOW. THURSDAYS
TEMPS WILL BE ON THE RISE AS A RESULT OF WARM AIR ADVECTION AND
DOWNSLOPE WARMING...WITH 50S TO 60S LIKELY ACROSS THE EASTERN
PLAINS AND 40S OUT WEST. WOULD EXPECT SOME MOUNTAIN WAVE CLOUDS AS
WELL IN THIS PATTERN AND A FEW LIGHT OROGRAPHIC RAIN/SNOW SHOWERS
IN THE SNOWY AND SIERRA MADRE MOUNTAINS.
A SOMEWHAT DISORGANIZED SHORTWAVE WILL MOVE ACROSS THE FORECAST AREA
THURSDAY NIGHT IN NW FLOW...ALONG WITH INCREASING MID LEVEL
MOISTURE. UPPER LEVEL FORCING LOOKS RELATIVELY WEAK WITH THIS
FEATURE...SO ANTICIPATE MAINLY OROGRAPHIC SHOWERS TO BE ENHANCED BY
THE WAVE WITH A FEW SNEAKING OFF THE MOUNTAINS AND INTO THE
IMMEDIATE EASTERN PLAINS THROUGH FRIDAY MORNING. LITTLE TO NO
ACCUMULATION WILL OCCUR OVER THE PLAINS AND HIGH VALLEYS...WITH A
FEW INCHES POSSIBLE IN THE MOUNTAINS. THE UPPER RIDGE WILL BUILD
OVERHEAD FRIDAY AND SATURDAY WITH MILD AND MAINLY DRY CONDITIONS
EXPECTED LATE FRIDAY THROUGH SATURDAY. THE NEXT UPPER TROUGH WILL
MOVE TOWARD THE FORECAST AREA SATURDAY NIGHT AND SUNDAY AND WILL
BACK UPPER LEVEL FLOW TO THE SOUTHWEST. THE LEE SIDE PRESSURE TROUGH
WILL DEEPEN IN ADVANCE OF THIS WAVE SO WILL SEE BREEZY SOUTHWEST
WINDS ACROSS THE AREA THROUGH MUCH OF THE WEEKEND. A COLD FRONT
ASSOCIATED WITH THIS SYSTEM WILL MOVE THROUGH THE AREA LATE IN THE
WEEKEND AND WILL BRING A RETURN OF MUCH COOLER TEMPS AND SNOW FOR
THE BEGINNING OF THE WEEK. WILL MAINTAIN LOW END CHANCES FOR SNOW AS
MODELS CONTINUE TO SHOW SOME STRENGTH AND TIMING DIFFERENCES WITH
THE UPPER TROUGH.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY MORNING)
ISSUED AT 1104 AM MDT TUE OCT 29 2013
TOUGH FORECAST FOR THE SOUTHEAST WYOMING AND NEBRASKA PANHANDLE
AIRPORTS TODAY. RELYING HEAVILY ON LATEST HRRR FORECAST THAT
BREAKS OUT CHEYENNE AND THE SOUTHERN PANHANDLE LATE THIS AFTERNOON
FOR A BRIEF TIME. FOR CHADRON AND ALLIANCE...THINK THESE AIRPORTS
WILL STAY DOWN ALL DAY. ALL AIRPORTS EAST OF THE LARAMIE RANGE
WILL GO DOWN ONCE AGAIN THIS EVENING AS UPPER LOW EJECTS SOME
ENERGY EAST. CONFIDENCE HIGH ON THIS HAPPENING. SHOULD SEE A
RETURN TO VFR CONDITIONS FROM WEST TO EAST LATE WEDNESDAY MORNING.
&&
.FIRE WEATHER...
ISSUED AT 238 AM MDT TUE OCT 29 2013
UPPER LEVEL LOW PRESSURE OVER NEVADA WILL MOVE INTO WYOMING TONIGHT.
THIS LOW WILL BRING WIDESPREAD LIGHT RAIN...DRIZZLE AND SNOW TO
THE DISTRICTS TODAY THROUGH WEDNESDAY. COLD TEMPERATURES AND HIGH
RELATIVE HUMIDITIES WILL PRECLUDE FIRE WEATHER CONCERNS. AS THE
LOW EXITS TO THE EAST LATE WEDNESDAY AND THURSDAY...SUSTAINED
WESTERLY WINDS OF 25 TO 35 MPH WITH GUSTS TO 50 MPH WILL BE
POSSIBLE FOR THE WIND PRONE AREAS OF SOUTHEAST WYOMING. DRIER AND
MILDER CONDITIONS WILL RETURN LATER THIS WEEK AND LAST THROUGH THE
WEEKEND. A CHANGE TO COLDER AND WETTER CONDITIONS IS EXPECTED FOR
EARLY NEXT WEEK.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...TJT
SHORT TERM...JAMSKI
LONG TERM...RJM
AVIATION...CLAYCOMB
FIRE WEATHER...JAMSKI
AREA FORECAST DISCUSSION...UPDATED
NWS LITTLE ROCK AR
1204 AM CDT THU OCT 31 2013
.DISCUSSION...
UPDATED TO INCLUDE THE 06Z AVIATION DISCUSSION BELOW...
&&
.AVIATION...
WIDESPREAD SHRA ONGOING ACROSS A LARGE PORTION OF THE STATE EARLY
THIS MORNING...WHICH WILL CONTINUE FOR MOST SITES INTO THE REST OF
THE MORNING HRS. EXPECT CONDITIONS AS LOW AS LIFR IN SOME
SPOTS...WITH SOME BREEZY SRLY WINDS. SOME TSRA WILL ALSO BE
POSSIBLE. THE COLD FRONT WILL MOVE EAST ACROSS THE STATE THIS
AFTERNOON...WITH PRECIP ENDING FROM WEST TO EAST BY THU EVENING.
IMPROVING CONDITIONS WILL ALSO BE SEEN BEHIND THE FRONT.
&&
.PREV DISCUSSION... /ISSUED 910 PM CDT WED OCT 30 2013/
UPDATE...
RADAR CONTINUES TO SLOWLY FILL IN AS STRONG STORM SYSTEM LIFTS OUT
OF THE ROCKIES AND INTO THE CENTRAL PLAINS. AS TROUGH APPROACHES
AND HEIGHTS CONTINUE TO FALL...EXPECT PRECIPITATION TO BECOME
HEAVIER WITH TIME. LATEST HRRR MODELS AND INCOMING NAM AGREE WITH
PREVIOUS MODEL RUNS AND POINT TO A FAIRLY RAPID INCREASE IN BOTH
COVERAGE AND INTENSITY OF THE PRECIPITATION AFTER MIDNIGHT. FEEL
THE PLACEMENT OF THE FLASH FLOOD WATCH STILL LOOKS GOOD IN SPITE
OF ACTUAL AMOUNTS STILL NOT VERY IMPRESSIVE AT THIS POINT.
ASSOCIATED FRONTAL BOUNDARY WILL STILL BE LOCATED OVER CENTRAL
OKLAHOMA EARLY THURSDAY MORNING AND SURGE ACROSS THE STATE DURING
THE DAY TAKING THE BULK OF THE PRECIPITATION WITH IT. A PERIOD
OF GUSTY WINDS WINDS SEEMS LIKELY BEFORE AND IMMEDIATELY AFTER
FROPA AND A LAKE WIND ADVISORY WILL LIKELY BE NEEDED AT THAT TIME.
ANY SEVERE THREAT WILL LIKELY BE OVER THE EAST LATER IN THE DAY.
OVERALL THE FORECAST REMAINS IN EXCELLENT SHAPE AND WILL LET IT
RIDE FOR NOW.
PREV DISCUSSION... /ISSUED 330 PM CDT WED OCT 30 2013/
SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT
PRIMARY FOCUS FOR THIS FCST WL CONT TO BE TNGT AND THU AS THE MUCH
DISCUSSED STORM SYS OVR THE ROCKIES HEADS EWD TNGT AND THU. PLENTY
OF MOISTURE WL CONT TO ADVECT INTO THE MID SOUTH AHEAD OF THIS
SYSTEM...BOTH FM THE GULF...AS WELL AS THE SUB TROPICAL JETSTREAM.
PROGGED PW/S VALUES CONT TO APCH AND/OR EXCEED 2 INCHES OVR MUCH OF
CNTRL AND SRN AR.
BULK OF THE RAINFALL TODAY HAS BEEN ACRS PARTS OF SRN AND NWRN AR.
RAIN COVERAGE WL CONT TO INCRS FM THE W AS THE NGT PROGRESSES...
ALONG WITH EMBEDDED TSRA. LATEST QPF GUIDANCE CONTS TO INDC
GENERALLY TWO TO FOUR INCHES OF RAINFALL THRU THU OVER A LARGE SWATH
OF CNTRL AND SRN AR...WITH ISOLD HIGHER AMTS ACRS SECTIONS OF SWRN
AR...ROUGHLY FM HOT TO TXK. FF WATCH ALREADY IN PLACE...BUT DID OPT
TO ADD THE REST OF THE SERN PART OF THE FA.
AS FAR AS SVR WX POTENTIAL GOES...AN ISOLD STRONG/SVR STORM CANNOT
BE DISCOUNTED OVR SWRN TNGT...BUT NOTHING WIDESPREAD. PARAMETERS ON
THU STILL LOOK TO BE A LOW CAPE/HIGH SHEAR SITUATION AS CLOUDS AND
ONGOING RAINFALL WL LIKELY LIMIT THE AMOUNT OF INSTABILITY.
HOWEVER...THERE COULD BE SOME SVR STORMS TO DVLP THU AFTN ACRS THE
ERN HALF OF AR IF THAT AREA MANAGES TO SEE A BREAK IN THE RAIN AND
CLOUDS. THE PRIMARY THREATS WOULD BE DAMAGING WINDS DUE TO THE
AMOUNT OF WIND ENERGY...AND POSSIBLY AN ISOLD TORNADO OR TWO.
RAIN WL END FROM THE WEST THU AFTN AND THU EVENING AS A CDFNT SWEEPS
THRU...WITH DRIER AND COOLER CONDS TO FOLLOW. ANOTHER UPR TROF WL
SWING THRU THE REGION FRI NGT AND EARLY SAT...BRINGING WITH IT SOME
INCRS IN CLOUDS AND A REINFORCING SHOT OF COOLER AIR.
LONG TERM...SUNDAY THROUGH WEDNESDAY
HIGH PRESSURE WILL BE ACROSS THE AREA TO START THE LONG TERM...BUT
WILL NOT LAST FOR LONG. THE NEXT LARGE UPPER TROUGH WILL MOVE INTO
THE REGION FOR THE MIDDLE OF NEXT WEEK...WITH ANOTHER ROUND OF HEAVY
RAINFALL POSSIBLE...AS MOISTURE VALUES WILL BE HIGH FOR THIS TIME OF
YEAR. FOR NOW...HAVE GONE WITH A BLEND OF MODELS FOR TIMING...WITH
THE EUROPEAN A LITTLE SLOWER THAN THE GFS. TEMPERATURES WILL WARM
INTO THE 60S AHEAD OF THE SYSTEM...WHICH WILL BE SLIGHTLY ABOVE
NORMAL.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 66 73 48 71 / 100 100 10 10
CAMDEN AR 66 75 48 75 / 100 100 10 0
HARRISON AR 63 71 45 68 / 100 80 10 0
HOT SPRINGS AR 67 74 48 73 / 100 90 10 0
LITTLE ROCK AR 67 75 51 72 / 100 90 10 0
MONTICELLO AR 66 74 51 75 / 80 100 20 10
MOUNT IDA AR 66 74 44 72 / 100 80 10 0
MOUNTAIN HOME AR 64 73 44 68 / 100 80 10 0
NEWPORT AR 65 73 51 70 / 100 100 10 10
PINE BLUFF AR 67 74 51 74 / 90 100 10 10
RUSSELLVILLE AR 67 74 45 70 / 100 80 10 0
SEARCY AR 66 74 47 70 / 100 100 10 10
STUTTGART AR 66 74 51 72 / 90 100 10 10
&&
.LZK WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR ARKANSAS-BRADLEY-
CALHOUN-CLARK-CLEBURNE-CLEVELAND-CONWAY-DALLAS-DESHA-DREW-
FAULKNER-GARLAND-GRANT-HOT SPRING-JEFFERSON-JOHNSON-LINCOLN-
LOGAN-LONOKE-MONROE-MONTGOMERY-NEWTON-OUACHITA-PERRY-PIKE-POLK-
POPE-PRAIRIE-PULASKI-SALINE-SCOTT-SEARCY-VAN BUREN-WHITE-
WOODRUFF-YELL.
&&
$$
AVIATION...62
AREA FORECAST DISCUSSION
NWS DES MOINES IA
335 AM CDT THU OCT 31 2013
.SHORT TERM /TODAY/...
ISSUED AT 335 AM CDT THU OCT 31 2013
LOW PRESSURE HAS MOVED INTO NERN IA NOW WITH THE COLD FRONT ALONG
THE EAST EDGE OF THE CWA. COLD FRONT WILL CONTINUE TO MAKE
PROGRESS...HOWEVER UPPER LOW NOT LIFTING THROUGH THE OK PANHANDLE
WILL RESULT IN AN EXPANSION OF THE RAIN WESTWARD AGAIN. HRRR HAD A
PRETTY GOOD HANDLE ON IT. ALTHOUGH THE FARTHEST WEST OF THE
MODELS...IT DOES NOT LOOK ALL THAT BAD GIVEN RADAR TRENDS.
EXPANSION HAS BEEN PUT INTO THE GRIDS FOR THIS MORNING WITH RAIN
GRADUALLY ENDING FROM THE WEST THIS AFTERNOON. TEMPS WILL NOT RISE
IN THE SOUTHEAST TODAY WITH MODEST RISES IN THE NORTHWEST. WINDS
WILL BECOME A SOMEWHAT GUSTY FOR A WHILE TODAY...BUT NOT MUCH HIGHER
THAN 20 MPH OR SO.
.LONG TERM /TONIGHT THROUGH WEDNESDAY/...
ISSUED AT 335 AM CDT THU OCT 31 2013
SYSTEM WILL DEPART TO THE EAST TONIGHT WITH SUBSIDENCE...CLEARING
AND COOLER TEMPERATURES. HOWEVER...ANOTHER SHORTWAVE WILL RAPIDLY
ADVANCE ON THE STATE FROM THE NORTHWEST ON FRIDAY. MOISTURE WILL
BE GENERALLY LACKING WITH THIS SYSTEM...HOWEVER DECENT MID LEVEL
FORCING AND STEEP LAPSE RATES WILL LEAD TO ISOLD/SCT SHOWER
DEVELOPMENT ACROSS NORTHERN IOWA BY AFTERNOON. FARTHER SOUTH...
SOUNDINGS ARE DRIER WITH LESS THREAT OF PCPN. WINDS WILL BE QUITE
STRONG ON FRIDAY AS WELL WITH DECENT PRESSURE GRADIENT AND NEARLY
UNIDIRECTIONAL FLOW THROUGH A GOOD DEPTH OF THE ATMOSPHERE...AND
HELPED ALONG WITH NEARLY ADIABATIC LAPSE RATES IN THE LOW LEVELS.
QUITE WEATHER IS EXPECTED THIS WEEKEND AS HIGH PRESSURE MOVES
ACROSS THE STATE. SOUTH WINDS WILL INCREASE QUICKLY ON SUNDAY ON
BACKSIDE OF HIGH AS LARGE WESTERN TROF DEVELOPS. GFS AND EURO
COMING CLOSER ON SOLUTIONS AND INDICATE A PROLONGED PERIOD OF
RAINFALL CHANCES FROM LATE SUNDAY NIGHT INTO WEDNESDAY. IOWA WILL
BE ON WESTERN EDGE OF WARM CONVEYOR BELT FROM GULF OF MEXICO WITH
DECENT RAINS EXPECTED...ESPECIALLY MOVING TO THE EAST ACROSS THE
STATE. TEMPERATURES MAY COOL ENOUGH BEHIND A SLOWLY MOVING COLD
FRONT FOR SOME TRANSITION TO SNOW BY TUESDAY NIGHT IN THE FAR
NORTHWEST.
&&
.AVIATION...31/06Z
ISSUED AT 1144 PM CDT WED OCT 30 2013
LOW MVFR AND IFR STRATUS WILL PERSIST ACROSS SITES THROUGH 12Z.
VISIBILITIES WILL ALSO BE IFR OR LOWER AT TIES WITH BR/FG. SYSTEM
WILL SLOWLY PUSH EASTWARD...WITH CEILINGS AND VISIBILITIES LIFTING
TO MVFR AND VFR AFTER 12Z AND WILL BE VFR THROUGH REMAINDER OF PERIOD.
WINDS WILL BE GUSTY AND NORTHWESTERLY THURSDAY.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...MS
LONG TERM...COGIL
AVIATION...AWB
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1146 PM CDT WED OCT 30 2013
.SHORT TERM /TONIGHT/...
ISSUED AT 314 PM CDT WED OCT 30 2013
INTERESTING FORECAST TONIGHT WITH THE SURFACE LOW OVER NW MO AND A
TROUGH EXTENDING INTO CENTRAL IOWA LOCATED FROM ALGONA THROUGH
CRESTON. THE WARM FRONT ASSOCIATED WITH THIS LOW IS STILL IN
NORTHERN MO AND IS JUST STARTING TO INCH INTO FAR SOUTHERN/SW IA.
THE MODELS HAVE CAUGHT ON TO TRENDING DOWN WITH POPS/QPF...
ESPECIALLY ACROSS THE WEST. THE RAP ACTUALLY HAD THE BEST HANDLE ON
THINGS FOR TONIGHT. ALTHOUGH ALL MODELS WERE TRENDING LOWER WITH
POPS...NAM/GFS STILL LOOKED A BIT OVERDONE AND HIT QPF MORE THAN
WHAT I THINK WILL OCCUR. CONSEQUENTLY THE AREA FOR PRECIP THIS
EVENING WILL BE ALONG OUR FAR SOUTHERN AND EASTERN AREAS...NEAR THE
FRONTAL BOUNDARY WHERE SHOWERS AND ISOLATED TO SCATTERED STORMS ARE
STILL POSSIBLE. THE THUNDERSTORMS WILL STILL BE CAPABLE OF
PRODUCING MODERATE TO HEAVY RAINFALL THOUGH I THINK THE HEAVIEST
RAIN WILL OCCUR SE OF OUR FORECAST AREA.
I END POPS THIS EVENING FROM W/NW TO ABOUT THE I-35 CORRIDOR BY 12Z.
INSTABILITY AND FORCING SHIFTS EAST OVERNIGHT AS WELL SO THUNDER
CHANCES DIMINISH AFTER 06Z BUT STILL LINGER ACROSS THE FAR SOUTHEAST
BY 12Z. PATCHY FOG STILL A CONCERN AS SOUNDING SHOW SATURATED
SOUNDINGS ACROSS CENTRAL IOWA. FOR NOW I AM NOT CONSIDERING DENSE
FOG THOUGH LOWER LYING AREAS AND LOCATIONS THAT RECEIVED AN INCH OF
RAIN TODAY COULD SEE AT LEAST LOCALIZED DENSE FOG OVERNIGHT. I WILL
BRIEF THE EVENING SHIFT ON THE POSSIBILITY OF DENSE FOG LATER
TONIGHT.
.LONG TERM /THURSDAY THROUGH WEDNESDAY/...
ISSUED AT 314 PM CDT WED OCT 30 2013
MAIN CHALLENGE IN THE NEAR TERM WILL BE THE EXITING OF OVERNIGHT
PRECIPITATION INTO THURSDAY MORNING. THE BULK OF THE RAIN AND ANY
LEFTOVER ISO THUNDER WILL BE EXITING THE AREA BY EARLY AFTERNOON
WITH SOME LINGERING SHOWERS SOUTHEAST THROUGH 00Z. OTHERWISE
...EXPECTING SIGNIFICANT CLOUD COVER OVER MUCH OF THE SOUTHEAST
HALF THROUGH MIDDAY FOLLOWED BY PARTIAL CLEARING DURING THE
AFTERNOON. SUBSIDENCE SHOULD BE OFFSET BY SOME COLD AIR ADVECTION
WHICH WILL RESULT IN LINGERING CLOUDS FOR THE DAY. HIGHS WILL ONCE
AGAIN REACH THE UPPER 50S SOUTHEAST WITH NEAR 50 HIGHS FAR NORTH
WHERE COLD AIR WILL ARRIVE SOONER. A SECONDARY COLD FRONT/WEAK WAVE
WILL TRACK SOUTHEAST THURSDAY EVENING. THIS WILL CONTINUE CLOUD
COVER ACROSS THE AREA SO OVERNIGHT LOWS WILL BE HELD IN CHECK
COMPARED TO CLEARING. LIMITED WARM AIR ADVECTION IS EXPECTED ON
FRIDAY WITH CLOUDS...SO HIGHS WILL ONCE AGAIN STRUGGLE TO REACH THE
LOWER TO MID 50S FOR THE DAY. THE MODELS ARE CONTINUING TO PICK UP A
WAVE IN THE FLOW OVER THE NORTH PACIFIC/GULF OF ALASKA NOW...WHICH
WILL RACE EAST AND THEN DROP SOUTHEAST INTO THE AREA BY FRIDAY
AFTERNOON. THOUGH GENERALLY MOISTURE STARVED...THIS FEATURE SHOULD
AMPLIFY AS IT HOOKS UP WITH THE H500 TROUGH STILL LINGERING OVER THE
CENTRAL PLAINS. THE TIMING OF THE FEATURE SUGGESTS THAT SOME LIGHT
SHOWERS MAY OCCUR LATE FRIDAY AFTERNOON OR EARLY EVENING PRIOR TO
THE SYSTEM MOVING EAST. THE EURO/GEM ALSO SUGGEST A BRIEF SHOT OF
COLD AIR ADVECTION FRIDAY NIGHT WITH THIS FEATURE REINFORCING THE
COOL WEATHER INTO SATURDAY. BOTH THE GFS AND NAM ARE FASTER WITH
ARRIVAL/DEPARTURE AND ARE ALREADY WARMING UP THE COLUMN SATURDAY
AFTERNOON. FOR NOW...WILL LEAN TOWARD MED RANGE SOLUTIONS AND DELAY
ONSET OF WARM AIR UNTIL LATER SATURDAY AND SUNDAY. WITH A H500
TROUGH JUST OFF THE COAST OF BRITISH COLUMBIA EXPECTED TO DIG
ONSHORE AND DEEPEN OVER THE NORTHERN ROCKIES BY SUNDAY...A NICE
FETCH OF SOUTHERLY FLOW WILL DEVELOP ACROSS THE REGION FOR SUNDAY.
H850 TEMPS WILL QUICKLY TURN THE CORNER AND RISE TO 3C TO 6C BY LATE
DAY...COMBINED WITH MIXING TO 875MB MAXT SHOULD RISE TO THE MID TO
UPPER 50S SOUTH AND AND LOWER 50S SOUTH. ALONG WITH THE INCREASING
SOUTHERLY FLOW...MOISTURE WILL BE RETURNING BY LATE SUNDAY NIGHT
THROUGH TUESDAY AS A DEEP SUBTROPICAL CONNECTION SETS UP WITH THE
GULF/PACIFIC BEING CHANNELED NORTH INTO THE CENTRAL PLAINS AND OHIO
RIVER VALLEY. SOME QUESTION ABOUT THE EXACT POSITION...BUT OVERALL
ADDITIONAL RAINFALL...EVEN IF MODEST OVER THE AREA...WILL BE
WELCOMED TO ADD TO TODAYS RAIN EVENT. IT APPEARS THAT THERE WILL
BE SEVERAL WAVES APPROACHING THE AREA BY EARLY NEXT WEEK INTO
MIDWEEK KEEPING RAINFALL IN THE FORECAST THROUGH AT LEAST
WEDNESDAY. FOR NOW...MODESTLY COOLER AIR FOLLOWS THE SYSTEM SO
HIGHS SHOULD TRACK JUST SLIGHTLY BELOW NORMAL FOR THIS TIME OF THE
YEAR.
&&
.AVIATION...31/06Z
ISSUED AT 1144 PM CDT WED OCT 30 2013
LOW MVFR AND IFR STRATUS WILL PERSIST ACROSS SITES THROUGH 12Z.
VISIBILITIES WILL ALSO BE IFR OR LOWER AT TIES WITH BR/FG. SYSTEM
WILL SLOWLY PUSH EASTWARD...WITH CEILINGS AND VISIBILITIES LIFTING
TO MVFR AND VFR AFTER 12Z AND WILL BE VFR THROUGH REMAINDER OF PERIOD.
WINDS WILL BE GUSTY AND NORTHWESTERLY THURSDAY.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...FAB
LONG TERM...REV
AVIATION...AWB
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1122 PM CDT WED OCT 30 2013
.AVIATION UPDATE...REGARDING 06Z TAF ISSUANCE. WIDESPREAD SHOWER AND
THUNDERSTORM ACTIVITY IS EXPECTED TO DEVELOP ACROSS THE FORECAST
AREA THURSDAY. THIS WILL BE ALONG AND AHEAD OF A STRONG COLD FRONT
MOVING ACROSS THE AREA. A FEW STRONG THUNDERSTORMS WILL BE
POSSIBLE. OTHERWISE...GUSTY SOUTHERLIES WILL CONTINUE IN ADVANCE
OF THE FRONT...WITH CEILINGS FALLING INTO AND REMAINING GENERALLY
WITHIN MVFR UNTIL FROPA.
&&
MARCOTTE
&&
.PREV DISCUSSION... /ISSUED 1030 PM CDT WED OCT 30 2013/
DISCUSSION...
UPDATED MOST GRIDDED ELEMENTS FOR THE NEXT 36 HRS OR SO. WHILE
MOST MODELS IN GENERAL DID FAIRLY POORLY WITH THE RAINFALL TODAY
AND THIS EVENING...THE HRRR HAS DONE A DECENT JOB DEPICTING
CONVECTION THIS EVENING GRADUALLY DECREASING IN INTENSITY AND
LIFTING NORTHWARD. WHLIE THE SPIGOT MAY NOT SHUT OFF
COMPLETELY...IT APPEARS THAT MOST AREAS SHOULD GET A BREAK FROM
HEAVY RAINFALL DURING THE OVERNIGHT HOURS...A MUCH NEEDED ONE FOR
PARTS OF EAST TEXAS INTO WEST CENTRAL LOUISIANA WHERE ESTIMATES OF
4 TO 6 INCHES WITH LOCALLY HIGHER AMOUNTS HAVE FALLEN. THIS IS
SQUARELY WITHIN THE FLASH FLOOD WATCH AREA...AND WITH ADDITIONAL
AMOUNTS OF 2 TO 4 INCHES...LOCALLY HIGHER...EXPECTED TO FALL
TOMORROW...HAVE EXTENDED THE WATCH THROUGH TOMORROW EVENING. THE
HRRR SUGGESTS A BAND OF HEAVY PCPN WILL BE ONGOING OR JUST
ENTERING EAST TEXAS BY DAYBREAK...AND SLOWLY PROGRESS EAST THROUGH
THE REGION ON THURSDAY INTO THURSDAY NIGHT.
A MODEST TO HIGH SHEAR/HELICITY AND LOW TO MODEST CAPE/INSTABILITY
ENVIRONMENT IS EXPECTED TO BE IN PLACE TOMORROW...AND SPC HAS
THE ENTIRE REGION OUTLINED IN SLIGHT RISK FOR SEVERE
THUNDERSTORMS...WITH TORNADOES/DAMAGING WINDS THE PRIMARY HAZARDS.
13
PREV DISCUSSION... /ISSUED 653 PM CDT WED OCT 30 2013/
AVIATION UPDATE...REGARDING 00Z TAF ISSUANCE. WIDESPREAD SHOWERS
AND A FEW THUNDERSTORMS OVER CENTRAL LOUISIANA INTO INTERIOR
SOUTHEAST TEXAS WILL CONTINUE TO ADVANCE NORTHEAST WITH RAIN
CHANCES THEN DIMINISHING. SHOWER AND THUNDERSTORM ACTIVITY WILL
RAMP UP AGAIN GOING THROUGH THURSDAY FROM WEST TO EAST AS A STRONG
COLD FRONT APPROACHES AND ADVANCES ACROSS THE AREA DURING THE LATE
AFTERNOON AND EVENING. UNTIL THE FROPA...A STRONG AND GUSTY
SOUTHERLY FLOW WILL CONTINUE...WITH MVFR CEILINGS OVERSPREADING
THE ENTIRE FORECAST AREA.
MARCOTTE
PREV DISCUSSION... /ISSUED 438 PM CDT WED OCT 30 2013/
DISCUSSION...
SHOWERS AND THUNDERSTORMS HAVE BEEN TRAINING ACROSS SOUTHEAST
TEXAS AND SOUTHWEST LOUISIANA NORTH OF THE I-10 CORRIDOR THIS
AFTERNOON. STORM TOTALS REPORTED HAVE RANGED FROM ONE TO FOUR
INCHES. THIS AREA OF SHOWERS IS ASSOCIATED WITH A FRONTAL BOUNDARY
THAT IS CURRENTLY MOVING INTO CENTRAL TEXAS. TEMPS TODAY HAVE
CLIMBED INTO THE LWR 80S OUTSIDE OF RAIN COOLED AREAS ON SOUTHEAST
WINDS.
AS A RESULT OF STRONG SOUTHEAST WINDS TIDES ALONG THE COAST ARE
RUNNING ONE TO TWO FEET ABOVE NORMAL. WINDS SOUTH OF THE I-10
CORRIDOR HAVE BEEN RUNNING AROUND 14 TO 18 MPH WITH GUSTS ABOVE
20 MPH AND THIS WILL CONTINUE INTO THE EVENING HOURS...BUT WILL
REMAIN BELOW WIND ADVISORY.
THIS ACTIVITY WILL CONTINUE INTO TONIGHT AND TOMORROW UNTIL THE
FRONTAL PASSAGE WHICH IS EXPECTED LATE THURSDAY NIGHT INTO EARLY
FRIDAY MORNING. THERE WILL BE A SMALL THREAT THAT A FEW STORMS MAY
BECOME SEVERE.
ALL THIS ACTIVITY SHOULD BE OUT OF THE REGION BEFORE THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 72 80 57 78 55 / 70 100 100 10 0
KBPT 74 80 59 77 55 / 70 100 70 10 0
KAEX 70 79 56 78 49 / 100 100 70 10 0
KLFT 72 81 64 78 55 / 20 100 100 10 0
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...FLASH FLOOD WATCH THROUGH THURSDAY EVENING FOR THE FOLLOWING
ZONES: ALLEN...BEAUREGARD...RAPIDES...VERNON.
COASTAL FLOOD ADVISORY UNTIL 7 PM CDT THURSDAY FOR THE FOLLOWING
ZONES: EAST CAMERON...IBERIA...ST. MARY...VERMILION...WEST
CAMERON.
TX...FLASH FLOOD WATCH THROUGH THURSDAY EVENING FOR THE FOLLOWING
ZONES: HARDIN...NORTHERN JASPER...NORTHERN NEWTON...
SOUTHERN JASPER...SOUTHERN NEWTON...TYLER.
COASTAL FLOOD ADVISORY UNTIL 7 PM CDT THURSDAY FOR THE FOLLOWING
ZONES: JEFFERSON.
GM...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THURSDAY FOR THE FOLLOWING
ZONES: COASTAL WATERS FROM CAMERON LA TO HIGH ISLAND TX OUT
20 NM...COASTAL WATERS FROM INTRACOASTAL CITY TO CAMERON LA
OUT 20 NM...COASTAL WATERS FROM LOWER ATCHAFALAYA RIVER TO
INTRACOASTAL CITY LA OUT 20 NM...WATERS FROM INTRACOASTAL
CITY TO CAMERON LA FROM 20 TO 60 NM...WATERS FROM CAMERON
LA TO HIGH ISLAND TX FROM 20 TO 60 NM...WATERS FROM LOWER
ATCHAFALAYA RIVER TO INTRACOASTAL CITY LA FROM 20 TO 60 NM.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
138 AM EDT THU OCT 31 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 420 PM EDT WED OCT 30 2013
WV IMAGERY AND RAP ANALYSIS SHOWING A BROAD UPPER TROUGH OVER THE
ROCKIES AND A WEAK UPPER RIDGE SHIFTING EAST ACROSS THE AREA. AS
THIS UPPER RIDGE SHIFTS EAST LATE THIS AFTERNOON AND EARLY THIS
EVENING...AREA WILL COME UNDER INCREASING SOUTHWESTERLY FLOW FROM
THE UPPER TROUGH...PUSHING OUR PWAT VALUES FROM 0.75IN (WHICH IS
STILL 150 PERCENT OF NORMAL) TO OVER 1.0IN (OR 200-225 PERCENT OF
NORMAL) OVER THE EASTERN CWA TONIGHT. THAT SOUTHWESTERLY FLOW ALOFT
WILL ALSO LEAD TO BROAD WARM AIR ADVECTION THROUGH THE
NIGHT...ESPECIALLY OVER THE CENTRAL AND EASTERN CWA. AT THE
SURFACE...A LOW THAT HAS DEVELOPED NEAR THE TEXAS PANHANDLE WILL BE
THE MAIN CONCERN FOR THE WEATHER FOR TOMORROW AFTERNOON INTO
TOMORROW NIGHT AS IT MOVES INTO THE GREAT LAKES REGION. BUT BEFORE
THAT OCCURS...AN ELONGATED SURFACE TROUGH WILL STRETCH NORTHEAST
FROM THAT LOW AND ACROSS UPPER MICHIGAN AND LAKE SUPERIOR TONIGHT.
THAT SURFACE TROUGH WILL COMBINE WITH THE SEVERAL SHORTWAVES MOVING
NORTHEAST FROM THE CENTRAL PLAINS (AND PRODUCING THE AREAS OF
CONVECTION AROUND SOUTHEAST IOWA AND NORTHWEST ILLINOIS)...ALONG
WITH THE BROAD WARM AIR ADVECTION AND MOISTURE TRANSPORT TO PRODUCE
SCATTERED SHOWERS WEST AND NUMEROUS/WIDESPREAD SHOWERS EAST TONIGHT.
AN INITIAL BAND OF RAIN SHOWERS AND DRIZZLE HAS BEEN MOVING
EAST-NORTHEAST ACROSS UPPER MICHIGAN THIS AFTERNOON AND EXPECT THAT
TO CONTINUE OVER THE NEXT COUPLE OF HOURS. WITH THE WARM AIR
ADVECTION AND MOISTURE TRANSPORT BEING VERY BROAD AND
COVERING MUCH OF THE CWA...IT/S HARD TO PIN DOWN AREAS WHERE THE
SHOWERS WILL BE LOCATED AND WHEN THEY WILL OCCUR. FEEL THAT THE
COVERAGE WILL LIKELY BE SCATTERED IN NATURE THROUGH THE
EVENING...AND THEN RAMP UP (ESPECIALLY OVER THE CENTRAL/EASTERN
CWA) TOWARDS MIDNIGHT AND THROUGH THE OVERNIGHT HOURS...AS THE
SHORTWAVE ENERGY IN IOWA MOVES THROUGH THE AREA. SINCE THERE IS
PLENTY OF LOW LEVEL MOISTURE...DID ADD MENTION OF PATCHY/AREAS OF
DRIZZLE FOR LATE THIS AFTERNOON AND INTO THE EVENING HOURS UNTIL
THE MORE WIDESPREAD PRECIPITATION ARRIVES. HIGHER RESOLUTION MODELS
SEEM TO BE STRUGGLING WITH THIS BROAD WAA...BUT SEEM TO FOLLOW THAT
SIMILAR IDEA...ALTHOUGH A FEW SHOW THE COVERAGE TO BE LACKING. IF
THE SHOWERS DEVELOP AS EXPECTED...THERE COULD BE SOME RUMBLES OF
THUNDER OVERNIGHT AS THERE IS A LITTLE BIT OF MUCAPE TONIGHT (50-150
J/KG). IN ADDITION...850-700/500MB LAPSE RATES DO INCREASE TO
6.5C/KM...SO CAN/T COMPLETELY RULE OUT SOME RUMBLES OF THUNDER AS
THE SHOWERS MOVE THROUGH. IF CONFIDENCE WAS HIGHER ON SHOWER
LOCATION AND INTENSITY...WOULD ADD IN ISOLATED THUNDER AND WILL
PASS ALONG TO THE EVENING SHIFT ON A POSSIBLE ADDITION.
ONCE THE SHORTWAVE MOVE THROUGH...HAVE SHOWN A DRYING TREND TO THE
POPS OVER THE WEST THIRD LATE TONIGHT. WITH WINDS SHIFTING TO THE
WEST OR EVEN WEST-NORTHWEST...THINK THE UPSLOPE DIRECTION TO THE
WINDS WILL PRODUCE SOME LIGHT DRIZZLE.
HAVE CONTINUED THE MENTION OF FOG FOR TONIGHT...BUT SPREAD INTO
THIS AFTERNOON AND EXPANDED TO BE WIDESPREAD OVER THE CENTRAL
HIGHER TERRAIN. WITH THE ABUNDANT MOISTURE AROUND AND LOW CLOUDS
AND FOG ALREADY IN PLACE...THINK THAT IS REASONABLE. AFTER THE
SHOWERS MOVE THROUGH...COULD SEE VISIBILITIES FALL TOWARDS
1/4-1/2MI IN THE CENTRAL CWA AND DID ADD A MENTION OF PATCHY DENSE
FOG.
FOR THURSDAY...WITH THE SHORTWAVES AND DEEPER MOISTURE PULLING
NORTHEAST AND AWAY FROM THE CWA THURSDAY MORNING...SHOULD SEE A
DIMINISHING TREND IN THE PRECIP FROM WEST TO EAST. WITH DRIER AIR
MOVING IN ALOFT AND PLENTY OF LOW LEVEL MOISTURE...EXPECT IT TO BE
A DREARY DAY OVER MUCH OF UPPER MICHIGAN. LOW CLOUDS WILL CONTINUE
TO COVER THE AREA AND WILL CONTINUE AREAS/PATCHY FOG OVER THE
HIGHER TERRAIN LOCATIONS AND IN AREAS FAVORED BY LIGHT
WEST-NORTHWESTERLY FLOW OVER THE WEST. HAVE ALSO CONTINUED LIGHT
RAIN SHOWERS OR DRIZZLE FOR THAT PERIOD OVER THE WESTERN CWA.
HEADING INTO THE AFTERNOON...THE SHORTWAVE AND PV ANOMALY WILL
EJECT OUT FROM THE SOUTHERN PLAINS AND INTENSIFY THE LOW AS IT
PULLS NORTHEAST TOWARDS THE GREAT LAKES REGION. MODELS HAVE BEEN
VARIABLE ON THE TRACK OF THE LOW...WITH A CONSENSUS NOW SHOWING IT
LOCATED OVER CENTRAL LAKE MICHIGAN AT 00Z. BUT THEY HAVE BEEN
CONSISTENT ON IT RAPIDLY DEEPENING THURSDAY NIGHT AS IT MOVES
THROUGH THE GREAT LAKES. THIS TRACK GREATLY INFLUENCES THE
PRECIPITATION CHANCES OVER THE SOUTHEASTERN 1/3RD OF THE CWA AND
HAVE FOLLOWED A GENERAL CONSENSUS WITH POPS INCREASING IN THAT AREA
TOWARDS LATE AFTERNOON. OVER THE REST OF THE AREA...THE
CLOUDY/DRIZZLY CONDITIONS WILL CONTINUE.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 420 PM EDT WED OCT 30 2013
THE MAIN FOCUS THIS FORECAST PERIOD WILL BE THE DEVELOPING LOW
PRESSURE OVER THE CENTRAL PLAINS...FORECAST TO MOVE INTO UPPER
MICHIGAN THURSDAY-FRIDAY. MODELS ARE GENERALLY IN DISAGREEMENT AS TO
THE LOWS POSITION BY 00-6Z FRIDAY. ALTHOUGH THE DIFFERENCES ARE
SLIGHT...THE LOCATION OF HIGHEST QPF WILL SHIFT DEPENDING ON THE LOW
TRACK. IF THE NAM VERIFIES...PRECIPITATION AMOUNTS WILL DIFFER
GREATLY FROM WHAT IS IN THE FORECAST NOW.
GENERALLY...THE 12Z GFS WRAPS THE SFC LOW UP SOONER THAN THE 00Z
ECMWF/12Z NAM RUN. THE LOW TRACKS FROM NORTHERN LAKE MICHIGAN AT 00Z
TO NORTHERN LAKE HURON BY 06Z...DEEPENING FROM 989MB TO 982MB. THE
NAM ON THE OTHER HAND...HAS A 992MB LOW OVER SOUTHERN LAKE MICHIGAN
AT 00Z...WITH A TROUGH EXPANDING NORTHWARD ACROSS THE LAKE. BY
6Z...THIS LOW DEEPENS TO 982MB OVER SAGINAW BAY. AT 00Z...THE 00Z
ECMWF POSITIONS A CLOSED LOW OVER CENTRAL LAKE MICHIGAN...A SORT OF
COMPROMISE BETWEEN THE GFS/NAM...BUT THEN ALIGNS ITSELF MORE
FAVORABLY WITH THE GFS BY 6Z...WITH THE LOW OVER NORTHERN LAKE
HURON. THE 12Z REGIONAL GEM BASICALLY IS A COMPROMISE BETWEEN THE
ECMWF/NAM...SO THIS WAS THE PRIMARY MODEL USED TO CREATE THE
WINDS/POPS FOR THIS FORECAST. THE GFS TRACK SEEMS TO BE TOO FAR
NORTH...AND IT STARTS TRENDING SOUTHWARD IN THE 6Z TIME
FRAME...WHICH MAKES ME FEEL MORE CONFIDENT USING THE GEM SOLUTION.
EXPECT LL FGEN BAND ASSOCIATED WITH A TROWAL-LIKE FEATURE TO SET UP
ACROSS EASTERN UPPER MICHIGAN/NEAR THE LAKE MI SHORE FROM 00Z-06Z.
EXPECT PRECIPITATION CHANCES TO BE GREATEST ALONG THIS AXIS. HIGHER
QPF AMOUNTS WERE LIMITED TO THE LAKE MICHIGAN SHORELINE...AS THIS IS
WHERE THE MID-UPPER LEVEL SUPPORT IS MAXIMIZED. MOISTURE WITH THIS
SYSTEM IS ABUNDANT...AS PWATS RISE TO AROUND 200 PERCENT OF
NORMAL...WITH THE HIGHEST VALUES ACROSS THE CENTRAL AND EAST.
THANKFULLY...850MB TEMPS ARE AROUND 0-9C DURING THIS EVENT...SO NO
SNOW IS EXPECTED. OVERALL TEMPERATURES/THICKNESSES ACROSS THE CWA
REMAIN SUPPORTIVE OF A RAIN EVENT THROUGH 12Z FRIDAY.
ONCE WE GET CLOSER TO THE LATE FRIDAY MORNING-SATURDAY TIME
FRAME...850MB TEMPS BECOME COOLER...AROUND -3 TO -6 AT THE
WORST...AND MAINLY OUT WEST. A SECONDARY SHORTWAVE ALOFT MOVES
THROUGH FRIDAY NIGHT AS WELL...WHICH WILL SUPPORT RAIN/SNOW SHOWERS
INLAND FROM THE LAKES DURING THIS TIME. OVERALL...WITH
NORTH-NORTHWESTERLY WINDS AND A LINGERING UPPER LEVEL
TROUGH/CYCLONIC FLOW...EXPECT THE LAKE EFFECT RAIN/SNOW SHOWERS TO
REMAIN THROUGH 06-12Z SUN...THOUGH THEY WILL TAPER OFF WITH TIME AS
THE FLOW GRADUALLY BECOMES MORE ANTICYCLONIC AND MOISTURE DWINDLES.
THE WEAK SFC HIGH PRESSURE WILL FINALLY MOVE IN SUNDAY...BRINGING A
BREAK TO THE MORE ACTIVE WEATHER.
FOR THE EXTENDED TIME FRAME...LOW PRESSURE DEVELOPS ACROSS THE
CENTRAL AND NORTHERN PLAINS AND MOVES INTO ONTARIO. THE ECMWF PULLS
THIS SURFACE LOW FURTHEST NORTH OVER JAMES BAY...AND THE GFS KEEPS
IT OVER NORTHERN ONTARIO. EITHER WAY...UPPER MICHIGAN WILL BE IN THE
SOUTHERLY FLOW AHEAD OF THE LOW...AND 850MB TEMPS REMAIN ABOVE ZERO
FOR THE MOST PART. EXPECT MAINLY RAIN CHANCES AS A RESULT...THOUGH
OVERNIGHT/MORNING COOLER TEMPERATURES COULD RESULT IN A RAIN/SNOW
MIX FOR SOME AREAS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 136 AM EDT THU OCT 31 2013
WARM MOIST AIR STREAMING NORTHEAST ACROSS UPPER MICHIGAN THIS
AFTERNOON AND TONIGHT ALONG AN ELONGATED SURFACE TROUGH WILL LEAD TO
LIFR CONDITIONS WITH LOW CLOUDS AND FOG AT CMX/SAW INTO THU MORNING.
A DOWNSLOPE SRLY WIND AT IWD WILL LIMIT FOG POTENTIAL EVEN WITH IFR
CIGS PREVAILING.
ALTHOUGH THE RAIN WILL DEPART FROM WEST TO EAST LATE TONIGHT INTO
EARLY TOMORROW MORNING...THE WINDS TURNING TO THE WEST/NORTHWEST
WILL FAVOR DRIZZLE FOR KCMX/KIWD AND THE UPSLOPE FLOW WILL KEEP
CEILINGS LOW. AT KSAW...WITH SRLY WINDS BECOMING NORTH...UPSLOPE
CONDITIONS WILL SUPPORT LOW CIGS AND FOG THROUGH THE FCST PERIOD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 420 PM EDT WED OCT 30 2013
A LOW PRESSURE SYSTEM DEVELOPING NEAR THE TEXAS PANHANDLE TODAY
WILL BE THE MAIN WEATHER MAKER FOR THE FORECAST PERIOD. THIS LOW
WILL SLIDE A TROUGH NORTHEAST INTO LAKE SUPERIOR TONIGHT AND WILL
LEAD TO WINDS INCREASING OUT OF THE SOUTH TO 20KTS OVER THE
EASTERN HALF OF THE LAKE. WINDS ARE THEN EXPECTED TO WEAKEN
THURSDAY MORNING AS THE LOW INTENSIFIES AND QUICKLY MOVES NORTHEAST
TO CENTRAL LAKE MICHIGAN BY THURSDAY EVENING. AS THE LOW FURTHER
INTENSIFIES AND MOVES ACROSS LAKE HURON ON THURSDAY NIGHT...EXPECT
NORTH-NORTHWESTERLY WINDS TO INCREASE THURSDAY NIGHT INTO FRIDAY
MORNING. THE STRENGTH OF THE WINDS WILL DEPEND ON THE EXACT TRACK OF
THE LOW...BUT THE CURRENT THINKING IS GUSTS UP TO 30KTS OVER THE FAR
SOUTHEASTERN PART OF LAKE SUPERIOR AND TO 20-25KTS ELSEWHERE. IF THE
LOW TRACKS A LITTLE FARTHER NORTH...COULD SEE SOME GALES OVER THE
SOUTHEAST PART OF THE LAKE.
THE LOW WILL CONTINUE NORTHEAST FRIDAY NIGHT AND SATURDAY...BUT
WILL LEAVE A SURFACE TROUGH OVER THE UPPER GREAT LAKES REGION
THROUGH SATURDAY EVENING. WINDS DURING THIS PERIOD SHOULD STAY
BELOW 20KTS. WEAK HIGH PRESSURE WILL BUILD IN FOR SUNDAY AND LEAD TO
WINDS FALLING BELOW 15KTS BEFORE SOUTHERLY FLOW INCREASES AHEAD OF A
LOW MOVING NORTHEAST THROUGH ONTARIO ON MONDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
DENSE FOG ADVISORY UNTIL 11 AM EDT /10 AM CDT/ THIS MORNING FOR
MIZ004-005-010>012-084.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...MCD
AVIATION...JLB
MARINE...SRF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1157 PM CDT WED OCT 30 2013
.UPDATE...
ISSUED AT 649 PM CDT WED OCT 30 2013
UPDATED GRIDDED AND TEXT PRODUCTS TO INCLUDE ISSUANCE OF A DENSE
FOG ADVY FOR THIS EVENING THROUGH LATE THU MORNING. OBS OF 1/2SM
OR LESS...WITH MANY 1/4SM OR LESS...HAVE BECOME COMMON IN MUCH OF
CENTRAL-SRN MN THIS EVE AND THIS IS EXPECTED TO SPREAD INTO
W-CENTRAL WI BY MIDNIGHT OR SO. LIGHT WINDS COMBINED WITH PLENTY
OF LOW LEVEL MOISTURE WITHIN THE BLYR HAVE CONTRIBUTED TO THE
DEVELOPMENT OF FOG OVER NEARLY THE ENTIRE COVERAGE AREA.
HRRR/SREF/HOPWRF ALL INDICATE THE DEGRADED VSBY TO REMAIN IN PLACE
FOR MUCH OF THE OVERNIGHT SO HAVE OPTED TO HOIST A DENSE FOG ADVY.
WILL MONITOR TRENDS AND TWEAK THE ADVY IF/AS NECESSARY.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 400 PM CDT WED OCT 30 2013
DREARY FALL WEATHER WILL CONTINUE TONIGHT AND EARLY THURSDAY
MORNING UNTIL A SURFACE LOW AND COLD FRONT SLIDE EAST OF THE
FORECAST AREA. SEVERAL AREAS OF DRIZZLE AND WIDESPREAD FOG HAVE
PERSISTED FOR MOST OF THE DAY. MSLP HAS FALLEN 5-7 MB IN FAR SOUTH
CENTRAL MN IN THE VICINITY OF THE DRY SLOT SHOWING UP ON
SATELLITE. THIS HAS INCREASED THE BL WINDS AND HELPED MIX OUT SOME
OF THE DENSE FOG OBSERVED EARLIER IN THE DAY. HOWEVER...ACROSS
MOST OF CENTRAL MN AND WEST CENTRAL WI...THE FOG HAS ACTUALLY
THICKENED IN MANY LOCATIONS. THESE SAME AREAS WILL HOLD ONTO LIGHT
ENE WINDS THROUGH AT LEAST 06Z /NEAR CALM AT TIMES/. THIS WILL
KEEP THE LOW FOG AND STRATUS IN PLACE. BETWEEN 09-12Z...THE FLOW
WILL INCREASE OUT OF THE W-NW AND ADVECT COOLER/BUT DRIER 925-850
MB AIR INTO MN. THIS SHOULD DO THE TRICK OF BRINGING AN END TO THE
PRECIP. LOCAL WRF SIMULATIONS AND THE PAST COUPLE HRRR RUNS
SUPPORT THIS SCENARIO AS WELL. WE REDUCED POPS/QPF TONIGHT ACROSS
MOST OF THE FORECAST AREA TO ACCOUNT FOR THE SOUTH-EAST TREND IN
THE 12-18Z GUIDANCE. FAR EASTERN PORTIONS OF THE FORECAST AREA
/SUCH AS ALBERT LEA TO EAU CLAIRE/ SHOULD BE RIGHT ALONG OR JUST
NORTH OF THE LOW TRACK AND COULD STILL SEE 0.10-0.25" BETWEEN
03-09Z TONIGHT. OTHERWISE...MUCH MORE THAN TRACE AMOUNTS MIGHT BE
DIFFICULT TO ACCUMULATE ACROSS THE REST OF THE FORECAST AREA. THE
TWIN CITIES METRO COULD STILL PICK UP A FEW HUNDREDTHS TONIGHT.
TOMORROW WILL BE COOL BEHIND THE COLD FRONT WITH LINGERING STRATO
CU...BUT THE WINDS WILL REMAIN ALMOST DUE WESTERLY AND THERE MAY
BE A FEW BREAKS IN THE CLOUDS DURING THE AFTERNOON.
NONETHELESS...MID TO UPPER 40S ARE EXPECTED FOR HIGHS...WHICH IS
JUST A FEW DEGREES BELOW NORMAL.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 400 PM CDT WED OCT 30 2013
NOTHING TOO SCARY WEATHER WISE ACROSS THE REGION THURSDAY EVENING
OTHER THAN A FEW SHOWERS OVER WEST CENTRAL WISCONSIN IN THE WAKE
OF A LOW PRESSURE SYSTEM. A SHORT WAVE AND WEAK LOW PRESSURE
SYSTEM REMAIN ON TRACK TO DROP SOUTHEAST ACROSS THE REGION FRIDAY
AND FRIDAY NIGHT. HIGH CHANCE POPS REMAIN IN PLACE ACROSS THE FA.
WOULD HAVE GONE TO LIKELY AT THIS POINT ACROSS EASTERN MN AND WEST
CENTRAL WI... BASED ON THE NAM AND GFS SOLUTIONS. HOWEVER... THE
GEM AND ECMWF ARE NOT AS ENTHUSIASTIC WITH A MUCH LIGHTER AND
PATCHY PRECIPITATION PATTERN.
HIGH PRESSURE WILL FOLLOW THIS SYSTEM FROM SATURDAY INTO SUNDAY.
SUNDAY LOOKS TO BE THE BEST OF THE TWO DAYS FOR SUNSHINE BUT IT
BECOME QUITE BREEZY/WINDY ACROSS THE FA... ESPECIALLY FROM WEST
CENTRAL INTO SOUTH CENTRAL MN... WHERE SW WINDS NEAR 25 MPH
GUSTING TO 35 MPH ARE LIKELY. THE WIND IS THE RESULT OF A
STRENGTHENING PRESSURE GRADIENT BETWEEN HIGH PRESSURE OVER THE
GREAT LAKES AND DEVELOPING LOW PRESSURE OVER THE WESTERN HIGH
PLAINS. THERE COULD BE A PRETTY GOOD RUN ON THE HIGH TEMPERATURES
FOR THE DAY ACROSS SOUTHWEST MN AS ALONG AS THE DEVELOPING
SOUTHERLY LOW LEVEL WAA PATTERN DOES NOT SLOW MUCH. PUSHED HIGHS
UP INTO THE MIDDLE 50S FOR THE SW CWA BASED ON H85 MIX DOWN FROM
THE ECMWF.
AN UNSETTLED WEATHER PATTERN WILL DOMINATE THE REGION FOR MUCH OF
NEXT WEEK AS YET ANOTHER LARGE STORM SYSTEM PUSHES INTO THE
ROCKIES BY MONDAY. THIS SYSTEM FEATURES BOTH NORTHERN AND SOUTHERN
STREAM ENERGY ALOFT. GFS/ECMWF SOLUTIONS HAVE BEEN MEANDERING
AROUND THE PAST FEW DAYS ON HOW THIS SYSTEM MOVES THROUGH OUR
AREA FROM MONDAY NIGHT INTO THURSDAY. THE GFS HAS BEEN TRYING TO
PHASE THE TWO STREAMS OVER THE CENTER OF THE COUNTRY BY WEDNESDAY
WITH SURFACE LOW PRESSURE TRACKING NORTHEAST FROM THE CENTRAL
PLAINS TO THE GREAT LAKES. THE ECMWF HAS KEPT SEPARATION BETWEEN
THE STREAMS. THE ECMWF HAS BECOME QUITE EXTREME TODAY CUTTING
OFF AN UPPER LOW NEAR NORTHERN MEXICO BY MID WEEK. OVERALL... A
SLOWER OUTCOME WILL LIKELY RESULT OVER WHAT THE GFS INDICATES AND
PERHAPS CLOSER TO THE ECMWF. HENCE... A RATHER WET PERIOD IS
LIKELY NEXT WEEK. THE THREAT FOR SNOW IS MINIMAL AS LONG AS THE
NORTHERN AND SOUTHERN STREAMS KEEP THEIR DISTANCE LIKE THE ECMWF
INDICATES. MORE PHASING LIKE THE GFS WOULD PREFER COULD LEAD TO
TROUBLE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1151 PM CDT WED OCT 30 2013
WIDESPREAD IFR-AND-WORSE CONDITIONS TO CONTINUE THROUGH THE
OVERNIGHT HOURS. SOME IMPROVEMENT IS BEING SHOWN IN FAR WRN MN
WITH VSBY IN THE 2SM-4SM RANGE...BUT THE MAJORITY OF CENTRAL-ERN
MN INTO WRN WI STILL SHOW 2SM OR LESS VSBY...ALONG WITH OVC003 OR
LOWER CEILINGS. DEGRADED CONDITIONS WILL LAST THROUGH DAYBREAK AND
LIKELY TO AROUND MIDDAY BEFORE APPRECIABLE IMPROVEMENT OCCURS.
IFR-MVFR CEILINGS WILL LIKELY PERSIST THROUGH TMRW AFTN WHILE
VSBYS IMPROVE QUICKER. CONDS LOOK TO REACH VFR BY EARLY EVENING
THU AND SOME CEILINGS MAY EVEN SCATTER OUT. WINDS WILL SHIFT TO W
AT ARND 10 KT AFTER REMAINING LGT/VRBL OVERNIGHT.
KMSP...IFR-OR-LOWER CONDITIONS...ESPECIALLY LIFR AND VLIFR...WILL
PREVAIL OVERNIGHT DUE TO FOG. VSBY WILL COMMONLY BE 1/2SM OR LESS
THROUGH DAYBREAK WITH CEILINGS IN THE 100-200 FT RANGE. CONDS WILL
SLOWLY IMPROVE DURING THE DAY TMRW...BUT IFR-OR-WORSE CONDITIONS
WILL LIKELY LAST THRU LATE MRNG INTO EARLY AFTN. THIS INCLUDES
VSBY 3SM OR LESS AND CEILINGS WELL BELOW 1700 FT. CONDITIONS
IMPROVE TO MVFR LATE TMRW AFTN AND CONTINUE IMPROVING TO VFR BY
TMRW EVE.
/OUTLOOK FOR KMSP/
FRI...MVFR CIGS POSSIBLE WITH CHC -SHRA. WINDS W 15G25 KT.
SAT...VFR. WINDS NW 10-15 KT.
SUN...VFR. WINDS SE 10-20 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...DENSE FOG ADVISORY UNTIL 10 AM CDT THURSDAY FOR MNZ041>045-
048>053-057>063-066>070-076>078.
WI...DENSE FOG ADVISORY UNTIL 10 AM CDT THURSDAY FOR WIZ014>016-
023>028.
&&
$$
UPDATE...JPC
SHORT TERM...CLF
LONG TERM...RAH
AVIATION...JPC
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1202 AM CDT Thu Oct 31 2013
.SHORT TERM...(This Evening through Thursday Afternoon)
Issued at 230 PM CDT WED OCT 30 2013
19Z surface analysis and visible satellite imagery depict a sharp
cold front extending from extreme NW MO to just west of Topeka to
just west of Wichita. This boundary has become nearly stationary
this afternoon, slowed by upstream pressure falls and increasing
southerly warm sector flow that has more than offset the anemic
post-frontal wind fields. The elevated mixed layer present in the
12Z KTOP sounding has been eliminating by a surge of mid-high level
subtropical moisture that overspread the area between 17-18Z per
water vapor imagery, and has resulted in widespread showers and
thunderstorms. This activity should continue to progress steadily
eastward over the next few hours, with the activity in the warm
sector diminishing and being maintained north of the warm front
across nrn MO.
Further west, satellite imagery has shown some thinning/partial clearing
along and ahead of the immediate frontal zone over eastern KS into
Kansas City. Enough insolation is expected to boost temperatures into
the lower 70s, coupled with dewpoints now in the mid 60s in the pre-
frontal moist axis. Although frontal convergence is presently weak
owing to light/calm winds on the cool side of the boundary, a short-
wave impulse over wrn KS is expected to lift across Kansas during
the late afternoon and early evening hours. Large scale ascent
associated with this feature should be sufficient for thunderstorms
to quickly develop along the frontal zone around 21-22Z. Increasing
destabilization in this region should yield SBCAPE upwards of 1500
J/kg co-located beneath an impressive mid-upper level wind field
(65-70 knots at 500mb and 120 knots at 250mb) that will shift toward
the KS/MO border by 00Z. The HRRR model, which has done extremely
well to this point, clearly shows the low level response to the upper
wave, with an increasing low level wind field this evening over ern
KS and far wrn MO, with low level SRH values increasing to between
200-300 m^2/s^s. Certainly the large scale environment would be
supportive of both supercells and smaller scale bowing segments
within a QLCS type of system. And although the warm front has become
rather diffuse from recent widespread convection, and convectively
induced boundary could also aid in the available boundary layer
vorticity. Bottom line is that we may see a period between roughly 22
and 02Z where the tornado potential becomes non-zero over the
southwest quadrant of the CWA.
In addition to the severe threat late this afternoon and early this
evening, moderate to heavy precipitation will likely train ahead of
the slow moving boundary through much of the overnight hours (and
into the day tomorrow). The deep subtropical moisture plume, with
direct connections to both the Gulf and the remnants of Hurricane
Raymond in the EPAC, have contributed to GPS measured precipitable
water column around 1.60" which is nearing the maximum values ever
recorded on this date. An intensifying low level jet this evening
and overnight will maximize rainfall efficiency by focusing moisture
transport and ascent along the frontal zone. Given that 1-2.5" of
rain has already fallen over the past 48 hours across portions of
the area, have gone ahead and issued a flash flood watch for areas
along and southeast of a St. Joseph to Trenton line, effective from
now through 18Z tomorrow.
Temperature wise, very warm and humid conditions will persist
through the warm sector overnight. Basically kept readings in the
mid 60s along and south of the MO river, with only a gradual drop
off through the 50s further north given the initial lack of cold
advection.
.LONG TERM...(Thursday Evening through Wednesday)
Issued at 230 PM CDT WED OCT 30 2013
Rain is expected to continue through the majority of the daytime
hours of Thursday as models have trended deeper and more developed
with upper energy rotating around the base of the larger trough.
Despite the surface front sinking into the southeastern third of
Missouri Thursday morning, the track of the upper wave would support
a large deformation rain band to form and spread across the CWA
through the day. Rain should finally taper off late Thursday
afternoon, leaving damp and cool conditions for Halloween evening.
Friday-Sunday: A secondary upper trough will pass through the region
on Friday ushering in slightly cooler air for Saturday. However,
mid-level ridging will quickly move eastward for the second half of
the weekend, and model guidance indicates a quick return of
southerly flow by Sunday morning. Strong warm advection should push
temperatures back into the lower 60s.
Sunday night - Wednesday: Stratus should stream northward Sunday
night, insulating the area from any extreme temperature drop. With
the next upper trough diving into the Four Corners region Monday
night, rain chances will begin to increase substantially by Tuesday
through Wednesday and have bumped up PoPs both days.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday Night)
Issued at 1155 PM CDT WED OCT 30 2013
A slow moving surface cold front is currently across northwestern
Missouri and is in the VC of STJ. This will help keep winds light and
variable through much of the night. A few light showers will continue
to move through MKC overnight with a few in the VC of MCI while STJ
will remain dry with fog reducing vsbys to 2SM. Cigs will be IFR at
MCI and STJ through the overnight hours while MKC will remain MVFR
through 09Z before dropping into IFR. Another round of showers and
thunderstorms which is associated with an upper level shortwave is
getting organized across northern Oklahoma. These showers will
continue to move northeastward overnight and move into the terminals
between 09Z-10Z. Light to moderate rain showers will continue through
16Z-17Z with IFR cigs persisting with light fog reducing vsbys to
4-5SM. After the main area of rain pushes off to the east of terminals,
there may continue to be a few light showers in the area however cigs
should improve to MVFR. As such have added a TEMPO group for
improving conditions by late morning/early afternoon. Cigs will
scatter out around 19Z-20Z before going clear tomorrow evening. After
generally light winds overnight, winds will become out of the north-
northwest tomorrow morning between 5-10kts. Winds tomorrow afternoon
will then back to the west-northwest before becoming westerly around
5kts around 00Z.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...FLASH FLOOD WATCH through Thursday afternoon FOR KSZ025-057-060-
103>105.
MO...FLASH FLOOD WATCH through Thursday afternoon FOR MOZ007-008-
013>017-020>025-028>033-037>040-043>046-053-054.
&&
$$
SHORT TERM...Bookbinder
LONG TERM...Dux
AVIATION...73
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
255 AM CDT THU OCT 31 2013
.DISCUSSION...
SKIES HAD CLEARED ACROSS ALL BUT THE SOUTHEAST PORTION OF THE
FORECAST AREA AT 07Z WITH UPPER TROUGH AXIS STILL OVER THE WESTERN
PLAINS. WV LOOP SHOWING STRONG VORT MAX COMING OUT OF NORTHEAST
NEW MEXICO WHICH MODELS LIFT TOWARD THE LOWER MISSOURI VALLEY
DURING THE DAY. THIS WILL LIKELY MAINTAIN SOME CLOUD COVER OVER
THE SOUTHEAST UNTIL PASSAGE SOMETIME THIS AFTERNOON WITH
INCREASING CLOUDS ELSEWHERE ACROSS THE AREA. HRRR SUGGEST SOME
CHANCE OF SHOWERS FOR FAR SOUTHEAST NEBRASKA AND SOUTHWEST IOWA SO
HAVE PLACED LOW POPS THERE THROUGH THE MORNING. PATCHY FOG MENTION
FOR PARTS OF THE NORTHEAST AND EAST CENTRAL AREAS.
WINDY CONDITIONS MOVE INTO THE AREA ON FRIDAY AS UPPER TROUGH AXIS
SHIFTS EAST OF THE AREA...OTHERWISE GENERALLY DRY WITH SEASONAL
TEMPERATURES EXPECTED INTO SATURDAY.
EXTENDED PERIOD STILL LOOKS TO TURN ACTIVE EARLY NEXT WEEK AFTER
A MILD START ON SUNDAY. PATTERN SIMILAR TO THE RECENT SYSTEM AS
ANOTHER DEEP TROUGH DEVELOPS OVER THE WESTERN CONUS WITH A COLD
FRONT OVER EASTERN PARTS OF KANSAS AND NEBRASKA MONDAY NIGHT INTO
TUESDAY. SETUP PROVIDES ANOTHER CHANCE OF PRECIP FOR THE AREA WITH
A MIX OF RAIN AND SNOW IN PARTS OF THE NORTHEAST WHERE COLDER
TEMPERATURES EXPECTED THIS TIME AROUND.
&&
.AVIATION...
06Z TAFS FOR KOFK...KOMA AND KLNK.
ALTHOUGH LOW CLOUDS CONTINUED TO GENERALLY CLEAR TO NEAR LINCOLN
THROUGH 06Z...A WEAK SURFACE LOW THAT WILL MOVE ACROSS NORTHEAST
NEBRASKA THROUGH EARLY THURSDAY WILL BRING A PERIOD OF LIGHTER
WINDS WHICH WILL LIKELY ALLOW SOME FOG AND POSSIBLY SOME LOW CIGS
TO RETURN TO SITES. CONFIDENCE IN TIMING OF RETURN OF CIGS/LOWER
VSBYS IS LOW...ESPECIALLY WITH HIGHER CLOUDS STREAMING NEWD OUT
OF KS. STRONGER NW WINDS DURING THE DAY THURSDAY SHOULD ALLOW FOR
VFR CONDITIONS AT ALL SITES AFTER MID-LATE THU MORNING...ALTHOUGH
COOL AIR ALOFT AND ANOTHER DISTURBANCE COULD POSSIBLY BRING A
PERIOD OF LOWER CIGS WHICH COULD BE AROUND FL020-030 AT KOFK AND
KOMA. HOWEVER...NO MVFR CIGS WERE MENTIONED DURING THE DAY
THURSDAY WITH THIS FORECAST.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
FOBERT/CHERMOK
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1239 AM CDT THU OCT 31 2013
.UPDATE...
ISSUED AT 1100 PM CDT WED OCT 30 2013
AS ALREADY EVIDENCED BY AUTOMATED OBS...AREA WEBCAMS AND A
PERSONAL OBSERVATION TRAVELING TO THE WFO AT 03Z...AT LEAST
PATCHY...SHALLOW FOG HAS DEVELOPED...AND WILL LIKELY CONTINUE
DEVELOPING ACROSS MUCH OF THE CWA AS THE NIGHT WEARS ON...UNLESS
AN INCREASE IN HIGH CLOUDS IS ENOUGH TO TURN THE TIDE. PER BOTH
THE HRRR AND NAM VISIBILITY PRODUCTS...THERE IS A CHANCE THAT A
SOMEWHAT WIDESPREAD AREA OF DENSE FOG COULD EVENTUALLY MATERIALIZE
MAINLY WITHIN THE EASTERN 1/2 OF THE CWA WHERE SURFACE WINDS WILL
REMAIN THE OVERALL-LIGHTEST. WILL BE KEEPING A CLOSE EYE ON FOG
EVOLUTION...BUT AT LEAST FOR NOW HAVE INSERTED 1 MILE OR LESS
VISIBILITY WORDING INTO THE FORECAST/HAZARDOUS WEATHER OUTLOOK
IN ALL AREAS TO GET THE BALL ROLLING. IN OTHER DEPARTMENTS...HAVE
SHAVED GENERALLY 2-3 DEGREES FROM PREVIOUS LOW TEMPERATURES IN
MOST AREAS...GETTING MORE OF THE CWA DOWN INTO THE LOW-MID 30S
EXCEPT FOR UPPER 30S FAR SOUTHEAST. HAVE HARDLY LOOKED AT PRECIP
TRENDS SINCE WALKING IN THE DOOR...BUT WILL KEEP THE SLIGHT
CHANCE OF RAIN GOING ACROSS SOUTHERN ZONES.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 352 PM CDT WED OCT 30 2013
THE CWA CONTINUES TO SIT UNDER SOUTHWESTERLY FLOW IN THE UPPER
LEVELS...WITH THE MAIN LOW LOCATED ROUGHLY OVER THE WY/SD/NE
BORDER AREA...AND TROUGH AXIS EXTENDING TO THE S/SW. THE
SHORTWAVE DISTURBANCE WHICH BROUGHT SOME STRONG/SVR THUNDERSTORMS
EARLY THIS MORNING HAS SHIFTED OFF TO THE EAST OF THE AREA...AND
OUTSIDE OF A FEW LINGERING SHOWERS AND PATCHY DRIZZLE THROUGH THE
EARLY AFTERNOON...THERE HASNT BEEN A WHOLE LOT GOING ON TODAY.
AFTER STARTING THE DAY COMPLETELY SOCKED IN WITH LOW LEVEL STRATUS
AND CEILINGS ARND 500FT...CLOUDS ARE STARTING TO BREAK UP A
BIT...WITH THE NW CURRENTLY SEEING SOME DECENT SUN...WITH CEILINGS
ELSEWHERE STARTING TO LIFT. SURFACE HIGH PRESSURE HAS SETTLED INTO
THE REGION...KEEPING WINDS NORTHWESTERLY AND ON THE LIGHTER SIDE.
BETTER CHANCES FOR PRECIPITATION HAVE SHIFTED EAST...SO HAVE
REMOVED POPS THE REST OF THIS AFTERNOON/EARLY EVENING.
LOOKING AT TONIGHT AND INTO TOMORROW MORNING...THERE ARE A COUPLE
OF CONCERNS. MAIN ONE IS WITH ANOTHER UPPER LEVEL SHORTWAVE
DISTURBANCE EXPECTED TO PUSH OUT OF THE FOUR CORNERS
REGION...SLIDING ACROSS KS. DECIDED TO INSERT A SLIGHT CHANCE POP
ACROSS OUR NC KS COUNTIES LATER THIS EVENING INTO TOMORROW
MORNING...WITH MOST MODELS SHOWING THAT POTENTIAL BEING THERE. NOT
ALL AGREE...AND KEEP ACTIVITY JUST TO THE SOUTH. ANOTHER CONCERN
IS WITH SOME PATCHY FOG...AS SURFACE HIGH PRESSURE REMAINS IN THE
AREA AND WINDS STAY ON THE LIGHTER SIDE. WILL HOLD OFF ON MENTION
FOR NOW...WITH MODELS SHOWING SOME DRIER AIR STARTING TO WORK IN
FROM THE WEST...BUT EVENING CREW WILL HAVE TO KEEP AN EYE ON
IT...AND SEE IF ANYTHING DEVELOPS ALONG A SURFACE BOUNDARY THAT
WILL BE MAKING ITS WAY INTO THE CWA.
THROUGH THE REST OF THE DAYTIME HOURS...ANY PRECIPITATION THAT
DOES WORK INTO NC KS IS EXPECTED TO BE OFF TO THE EAST BY MIDDAY
AS THE MAIN MID/UPPER LEVEL TROUGH AXIS SWINGS THROUGH...WITH THE
REST OF THE AFTERNOON DRY. A REINFORCING SHOT OF NORTHWESTERLY
WINDS IS EXPECTED AS THE TROUGH MOVES THROUGH...AND A BREEZY
AFTERNOON IS EXPECTED...WITH SPEEDS IN THE 15 TO 25 MPH RANGE. AS
FAR AS TEMPERATURES GO...THE DOWNSLOPING COMPONENT TO THE WINDS
ALONG WITH A SLIGHT BUMP UP IN TEMPS ALOFT IS EXPECTED TO RESULT
IN HIGHS IN THE MID 50S IN THE NORTHEAST TO LOW 60S IN THE
SOUTHWEST.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 352 PM CDT WED OCT 30 2013
BY THURSDAY EVENING...THE MAIN UPPER LEVEL TROUGH WILL SHIFT EAST
OF THE REGION...WHILE A STRONG UPPER LEVEL RIDGE SLIDES INLAND ON
THE WEST COAST. A SECONDARY WEAKER WAVE WILL TRANSCEND SOUTH
ACROSS THE TROUGH AXIS THROUGHOUT THE DAY ON FRIDAY. AT THE
SURFACE...LOW PRESSURE TO THE EAST AND HIGH PRESSURE ALONG THE
WEST COAST WILL GENERATE A TIGHT PRESSURE GRADIENT ACROSS THE
PLAINS. THEREFORE...EXPECTING STRONGER NORTHWEST WINDS ACROSS THE
REGION ON FRIDAY...COMBINED WITH DECREASING DEWPOINTS. HEADING
INTO THE WEEKEND...EXPECT THE UPPER LEVEL RIDGE TO SHIFT EASTWARD.
SURFACE HIGH PRESSURE WILL KEEP THINGS FAIRLY QUIET ACROSS THE
PLAINS WITH MOSTLY SUNNY SKIES AND TEMPERATURES IN THE 50S TO 60S.
THE NEXT UPPER LEVEL WAVE/TROUGH IS ON TAP FOR MONDAY INTO
TUESDAY...AS A STRONG UPPER LEVEL WAVE DIVES SOUTHWEST FROM
BRITISH COLUMBIA INTO IDAHO AND MONTANA. THE GFS SOLUTIONS
REMAINS A BIT MORE BROAD WITH THE WAVE AND NOT AS DEEP AS THE
ECMWF SOLUTION...ALTHOUGH NEITHER BECOME CLOSED AT 500 MB. AT THE
SURFACE...TWO AREAS OF LOW PRESSURE...ONE ALONG THE FRONT RANGE
AND A SECOND ACROSS SOUTHERN CANADA WILL DRAG A COLD FRONT THROUGH
THE AREA SOMETIME MONDAY MORNING. AGAIN...TIMING REMAINS A BIT
UNCERTAIN BETWEEN THE TWO LONG TERM MODEL SOLUTIONS. BEHIND THE
FRONT...COLDER 850 MB AIR WILL BEGIN TO INFILTRATE THE REGION.
BOTH MODELS DO INDICATE SOME PRECIPITATION AROUND THE REGION
MONDAY NIGHT...BUT THE ECMWF SUGGESTS A MORE EXPANSIVE AREA. AT
THIS TIME...CURRENT THINKING...SHOULD PRECIPITATION BE REALIZED
BEHIND THE FRONT...TEMPERATURES ALOFT SHOULD BE COLD ENOUGH FOR AT
LEAST A RAIN SNOW MIX ESPECIALLY ACROSS NORTHWESTERN ZONES.
UNTIL THE TROUGH AXIS FINALLY SHIFTS ACROSS THE PLAINS BY
WEDNESDAY...COOLER AIR WILL CONTINUE TO TAKE HOLD ACROSS THE
PLAINS. AS SUCH...EXPECT HIGH TEMPERATURES TO DROP INTO THE LOWER
50S...POSSIBLY EVEN 40S FOR HIGHS FOR THE BEGINNING OF THE
WORKWEEK.
&&
.AVIATION...(FOR THE 06Z KGRI TAF THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1238 AM CDT THU OCT 31 2013
COMPARED TO THE PREVIOUS ROUTINE ISSUANCE 6 HOURS AGO...THINGS
HAVE DEFINITELY TAKEN A TURN FOR THE WORSE THANKS TO THE
DEVELOPMENT OF SHALLOW FOG...AT LEAST THROUGH THE EARLY-MID
MORNING HOURS. FOR NOW...WILL ADVERTISE A PREVAILING IFR
VISIBILITY THROUGH 15Z...AND WILL ALSO RUN WITH A TEMPO GROUP FOR
THE POSSIBILITY...IF NOT LIKELIHOOD...OF OFF AND ON LIFR
VISIBILITY/CEILING. OUTRIGHT DENSE FOG IN VLIFR IS NOT OUT OF THE
QUESTION...BUT WILL NOT GO QUITE THAT LOW YET UNLESS OBS
EVENTUALLY SUPPORT IT. FOG ISSUES SHOULD ABATE FAIRLY QUICKLY ONCE
WEST-NORTHWEST BREEZES PICK UP DURING THE DAY...AND HAVE A RETURN
TO VFR CONDITIONS STARTING AT 15Z AND LASTING THROUGH THE REST OF
THE PERIOD. THESE BREEZES WILL CARRY AN AFTERNOON GUST POTENTIAL
UP TO AROUND 25KT...BEFORE STEADILY SUBSIDING BY EARLY EVENING TO
AROUND 10KT OR LESS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...PFANNKUCH
SHORT TERM...ADO
LONG TERM...SALTZMAN
AVIATION...PFANNKUCH
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
339 AM EDT THU OCT 31 2013
.SYNOPSIS...
A WARM FRONT WILL GENERATE SHOWERS TODAY PRIMARILY THROUGH MID
AFTERNOON. A STRONG COLD FRONT WILL BRING ANOTHER ROUND OF SHOWERS
LATE TONIGHT THROUGH LATE FRIDAY MORNING, ALONG WITH STRONG
GUSTY WINDS. FRIDAY AFTERNOON THROUGH SATURDAY MORNING WILL BE
PRIMARILY DRY, BEFORE SCATTERED SHOWERS IMPACT THE AREA SATURDAY
AFTERNOON.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
330 AM UPDATE...
UL LOW SITTING UP OVR THE DAKOTAS AND EJECTING SLOWLY TO THE EAST.
SIGNIFICANT MOISTURE IS CREEPING UP AHD OF LOW WITH PW VALUES INCRSG
TO 40 MM (1.5 INCHES) OVR THE MID-MS VLY. THIS IS PROGGED TO WORK UP
INTO THE REGION LATE THIS AFTN.
04Z HAND ANALYSIS PLACES WMFNT EXTENDING FM SFC LOW IN IOWA INTO NRN
INDIANA AND OHIO AND SLOWLY HEADING NORTH. DWPTS SOUTH OF THE BNDRY
IN THE MID-ATLANTIC STATES ARE IN THE 50S AND WL WORK UP THIS WAY
THIS AFTN.
AREA OF MODERATE TO HVY RAIN ACRS LWR MICHIGAN DVLPNG IN VICINITY OF
SFC WMFNT ON NOSE OF LLJ. LATEST HRRR RUN BRINGS PCPN INTO WRN ZONES
BY 11Z AND OVRSPRDS MOST OF THE REGION BY AFTN. MAY BE BROKEN ACRS
SRN SXNS THIS AFTN IN THE FORM OF SCTD SHOWERS BASED ON WHAT IS
CURRENTLY GOING ON SOUTH OF SFC WMFNT, THUS WL KEEP JUST SCTD SHOWER
MENTION ALONG AND SOUTH OF THE NRN TIER OF PA.
AFTN MAXES WL TOP OUT IN THE L/M 60S AS 925MB TEMPS CLIMB UP TO ARND
10-12C TDA. THIS IS ALL COURTESY OF WAA THAT WL COMMENCE ACRS THE
REGION AS WMFNT PASSES THRU. CLDY SKIES EXPECTED FOR MOST OF THE DAY
WITH SHOWER ACTIVITY LKLY KEEPING TEMPS FM GETTING OUT OF CONTROL.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
330 AM UPDATE...
PHASING OF S/WVS EXPECTED TONIGHT RESULTING IN DEEPENING SFC LOW
ACRS THE GREAT LKS. H8 LLJ GETS CRANKING BY MIDNIGHT ACRS THE AREA
TO +60KTS THEN ABV 70KTS BY 09Z. BASED ON TRACK OF APPROX 980MB SFC
LOW ACRS SRN ONTARIO BY ALL MODELS, WITH 00Z NAM BEING A TOUCH
FURTHER NORTH, HV DECIDED TO UPGRADE TO HIGH WIND WARNING. BASED ON
LOCAL SYNOPTIC WIND STUDY 6-HR RISE/FALL COUPLET LOOKS TO BE IN THE
BALLPARK FOR HIGH WIND EVENT AND CONFIDENCE IS THERE THAT EXISTING
CNTYS IN WATCH WILL SEE HIGH WINDS AFTER MIDNIGHT TONIGHT. WL ALLOW
DAYSHIFT TO EVALUATE THE NEED FOR WIND ADVISORY ACRS RMNG AREAS TDA.
GIVEN THE STRENGTHENING LLJ AND PHASING OF VORT MAXES TONIGHT EXPECT
OCNL MODERATE SHOWERS LATE WITH QPF AMNTS ACRS THE FAR NORTH IN
VICINITY OF WMFNT APPCHG 1 INCH THRU 12Z FRIDAY. ELSEWHERE EXPECT
ARND 0.50 INCHES.
THO INSTABILITY IS VRY POOR THRU 12Z FRIDAY HV ADDED IN AN ISOLD
THUNDER MENTION AS SHOWALTERS/LI VALUES DIP BLO 0C BTWN 09Z AND 15Z
FRIDAY. CAPES VALUES LOOK TO BE PRETTY PUNY DRG THIS TIME WITH JUST
A COUPLE HUNDRED JOULES, HWVR DYNAMICS ARE EXTREMELY IMPRESSIVE AND
LOW-LVL LR ARE STEEP JUST ALONG AND AHD OF FRONT THUS THINK THAT
THUNDER AT LEAST DESERVES A MENTION, ESPECIALLY CONSIDERING
LIGHTNING STRIKES CURRENTLY OVR LK ERIE.
FROPA LOOKS TO OCCUR SOMETIME FRI MRNG/AFTN WITH HIGH TEMPS ONCE
AGAIN RISING INTO THE 60S ACRS MOST OF THE AREA, THO EXTRM WRN ZONES
MAY TOP OUT ARND 60F. APPEARS THAT THERE WILL BE A SHARP GRADIENT TO
PCPN WITH SHOWERS ENDING IN AREAS WEST OF I-81 AT 18Z AND LINGERING
ACRS ERN ZONES FOR ANOTHER HR OR TWO AFT THIS TIME. CAA WL BE
DELAYED UNTIL THE VRY END OF THE SHORT TERM WITH OVRNGT MINS AND
AFTN MAXES STILL ABV NORMAL FOR SATURDAY.
ANOTHER TROF/ASSOC SFC LOW WL MV INTO AREA FM THE NW BY 12Z
SATURDAY. WINDS WL BCM SRLY AHD OF THIS SFC SYSTEM AND QUICKLY SHIFT
ARND TO THE NW AS LOPRES PASSES ON SATURDAY. THIS WL SET THE STAGE
FOR LK EFFECT SHOWERS ON SAT AFTN AND EVENTUALLY A MIX WITH AND
CHANGE OVR TO SNOW ON SUN MRNG. HV MADE NO CHGS TO THESE GRIDS AT
THIS TIME DUE TO NEAR TERM CHALLENGES.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
2 AM UPDATE...
JUST MINOR CHANGES AND STILL BASED ON WPC GUIDANCE. PROGRESSIVE
PATTERN WITH UPPER LEVEL TROF EXITING THIS WEEKEND THEN UL HEIGHTS
BUILD AGAIN WITH A LARGE SFC HIGH PRESSURE MONDAY TO WED. THURSDAY
MORE SHOWERS AS A COLD FRONT AND TROF APPROACH.
PREVIOUS DISCUSSION...
A QUIET PD IS IN STORE FOR THE FCST AREA AFTER THE DEPARTURE OF
THIS WEEKEND`S SYSTEM. LAKE ENHANCED -SHSN DUE TO DEPARTING UPR
LVL TROF WILL TAPER OFF ON SUNDAY...WITH SFC RIDGING AND RAPIDLY
RISING HGTS EARLY NXT WEEK AS ANOTHER DEEP TROF DIGS INTO THE
CNTRL U.S.. THIS SYSTEM WILL BEGIN TO APPROACH THE FCST AREA LATE
IN THE FCST PD. MAXES MODERATING FROM THE U40S ON MONDAY TO THE
MID 50S BY WED.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
130 AM UPDATE...
MAINLY VFR CONDITIONS WILL QUICKLY FALL TO MVFR AND MAYBE IFR THIS
MORNING AS A DEEP STRONG SW BRINGS MOISTURE AND SHOWERS AT LOW
LEVELS. A LOW LEVEL MARINE LAYER HAS GOTTEN TO AVP WITH 1K FT CIGS
AND 2 TO 3 MILES VSBY. THIS WILL CONTINUE AND COULD DROP CIGS TO
IFR. THIS MOISTURE STAYING SOUTH OF THE ELM AND BGM BUT NOW LESS
THAN 50 MILES AWAY. MVFR CIGS IN WRN PA WILL COME INTO THE AREA BY
13Z WITH SHOWERS BY 16Z. SHOWERS COULD HAVE MVFR VSBYS. BY 18Z
SOUTH CENT NY AND AVP SHOULD BE DRY AND IN THE WARM SECTOR. CIGS
SHOULD LIFT SOME BUT REMAIN MVFR. VSBYS WILL RETURN TO VFR. AT SYR
AND RME SHOWERS WILL LINGER OFF AND ON ALL DAY WITH MAINLY MVFR
CONDITIONS. THIS EVENING SHOWERS COME BACK IN EVERYWHERE.
LIGHT E TO S WINDS WILL INCREASE TO 10 TO 15 WITH HIGHER GUSTS
TODAY AND CONTINUE INTO TONIGHT. INCREASING SSW FLOW IN LOWEST
FEW THOUSAND FEET AGL COULD ALSO CAUSE MARGINAL LLWS CONDITIONS
TOWARDS 09Z-14Z TIME PERIOD IF ADEQUATE MIXING OF WINDS DOWN TO
SURFACE DOES NOT OCCUR. MOST LIKELY LLWS AT KRME WHERE LOCALIZED
ESE VALLEY WIND WILL OPPOSE THE STRONGER 30-35 KT SSW WIND IN
LOWEST 2 KFT AGL...BUT LEFT OUT LLWS FOR OTHER TERMINALS WHERE IT
WILL NOT BE AS LIKELY /THOUGH POSSIBLE...ESP KELM/.
OUTLOOK...
THU OVERNGT....MVFR/IFR IN SHRA. STRONG GUSTY SSW
WINDS...ESPECIALLY KSYR-KRME.
FRI/FRI NGT...VFR. STRONG GUSTY SW TO W WINDS FRI MRNG...ESPECIALLY
KSYR-KRME.
SAT/SAT NGT...MVFR IN SHRA/SHSN PRIMARILY CNTRL NY.
SUN...MVFR EARLY CNTRL NY IN -SHRA/-SHSN...IMPRVG TO VFR.
MON...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...HIGH WIND WARNING FROM 2 AM TO 2 PM EDT FRIDAY FOR NYZ009-
015>018-036-037.
&&
$$
SYNOPSIS...PVN
NEAR TERM...PVN
SHORT TERM...PVN
LONG TERM...TAC
AVIATION...TAC
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
313 AM CDT THU OCT 31 2013
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 313 AM CDT THU OCT 31 2013
WHEN TO END DENSE FOG ADVISORY AND PRECIP CHANCES THROUGHOUT THE
PERIOD WILL BE THE MAIN FORECAST PROBLEMS FOR THE SHORT TERM.
CLEARING LINE HAS MOVED INTO THE WESTERN CWA...ALTHOUGH STILL
PLENTY OF CLOUDS OVER THE VALLEY AND POINTS EASTWARD. VISIBILITIES
HAVE BEEN IMPROVING OVER THE LAST FEW HOURS...AND THINK WITH LIGHT
WEST WINDS STARTING UP WE WILL SEE THAT TREND CONTINUE. ON THE
OTHER HAND...SOME SPOTS ARE STILL DOWN AROUND 1/2 MILE...AND WE
ARE HEADED TOWARDS THE MOST LIKELY TIME PERIOD FOR FOG. WILL HOLD
ONTO THE ADVISORY FOR NOW AND TAKE A SECOND LOOK AT THE 12Z UPDATE.
THE WEST WINDS WILL CONTINUE TO SLOWLY PUSH THE LOW LEVEL MOISTURE
EASTWARD TODAY...ALTHOUGH THE MODELS ALL ARE IN DECENT AGREEMENT
ON KEEPING THE EASTERN COUNTIES SOCKED IN WITH CLOUDS. LOWERED
TEMPS A FEW DEGREES IN THAT AREA INTO THE LOWER 40S...WITH
SLIGHTLY WARMER TEMPS FURTHER WEST WHERE THERE COULD BE SOME
SUNSHINE.
TONIGHT...A DECENT SHORTWAVE TROUGH WILL BE DIGGING DOWN INTO ND
AND BRINGING A FAIR AMOUNT OF MOISTURE WITH IT. CLOUDS WILL
INCREASE AGAIN...AND WITH WEST WINDS BRINGING SOME MIXING...THINK
THAT WILL BE ENOUGH TO KEEP TEMPS IN THE LOW 30S EVEN WITH SOME
COLD AIR ADVECTION. MODELS ALL START BRINGING SOME LIGHT PRECIP
INTO THE WESTERN CWA DURING THE LATE NIGHT HOURS AS THE SHORTWAVE
APPROACHES. ADJUSTED TIMING OF POPS...STARTING THEM IN THE
NORTHWEST BEFORE SUNRISE AND SPREADING EASTWARD DURING THE DAY ON
FRIDAY. FOR NOW KEPT POPS IN THE CHANCE RANGE AS THE SYSTEM MOVES
THROUGH.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 313 AM CDT THU OCT 31 2013
SFC HIGH PRESSURE WILL BUILD IN FRIDAY NIGHT...REDUCING CLOUD
COVER BUT WITH WESTERLY SFC WINDS ADVECTING IN SOME SLIGHTLY
WARMER AIR DID NOT DROP LOWS MUCH...ONLY IN THE UPPER 20S TO LOW
30S. SATURDAY SHOULD BE FAIRLY QUIET AS THE UPPER RIDGE AXIS
BEGINS TO MOVE INTO THE PLAINS. WINDS WILL SHIFT AROUND TO THE
SOUTH AND WITH SOME SUNSHINE HIGHS SHOULD CLIMB INTO THE UPPER
40S. THE SOUTH WINDS WILL CONTINUE TO PICK UP INTO SATURDAY NIGHT
AND MIXING WILL KEEP LOWS IN THE LOW 30S.
SUNDAY THROUGH WEDNESDAY NIGHT...00 UTC GFS/ECMWF IN REASONABLE
AGREEMENT BOTH SHOWING A DEEP PACIFIC TROUGH STALLING ACROSS THE
ROCKIES AND EJECTING SHORT-WAVES ACROSS THE NORTHERN PLAINS. SOME
DIFFERENCES IN MODEL TIMING AND STRENGTH OF THESE WAVES WITH THE
ECMWF MORE PROGRESSIVE AND WEAKER THAN THE GFS. EITHER WAY...THE
BEST CHANCE FOR PRECIPITATION WILL BE SUNDAY NIGHT THROUGH MONDAY
WITH THE MAIN FRONTAL PASSAGE. THERMAL PROFILES ARE GENERALLY WARM
ENOUGH FOR ALL RAIN WITH THE THREAT FOR A RAIN/SNOW MIX AT NIGHT.
TUESDAY/WEDNESDAY LOOK MOSTLY DRY AT THIS TIME. EXPECT CONSIDERABLE
CLOUDINESS THROUGH THE PERIOD WITH A SLIGHT COOLING TREND TUESDAY
AND WEDNESDAY IN THE WAKE OF THE COLD FRONT. DAYTIME HIGHS IN THE
MID TO UPPER 40S SUNDAY WILL FALL INTO THE UPPER 30S TO LOWER 40S
BY MID-WEEK. NIGHTTIME LOWS WILL RANGE FROM THE MID 20S TO MID
30S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1148 PM CDT WED OCT 30 2013
IFR/MVFR CIGS ACROSS THE REGION WILL ONLY SLOWLY CLEAR FROM WEST
TO EAST THROUGH THE PERIOD. USED THE RAP GUIDANCE FOR HEIGHT AND
TIMING PURPOSES AS IT APPEARS TO HAVE A GOOD HANDLE ON THE CURRENT
SITUATION.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR MNZ015>017-
022>024-027-028-030>032-040.
&&
$$
SHORT TERM...JR
LONG TERM...JR/ROGERS
AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1148 PM CDT WED OCT 30 2013
.UPDATE...
ISSUED AT 928 PM CDT WED OCT 30 2013
VISIBILITIES DUE TO FOG CONTINUE TO LOWER ACROSS PORTIONS OF WEST
CENTRAL MINNESOTA THIS EVENING. ALTHOUGH 925MB-850MB WINDS ARE
EXPECTED TO INCREASE AFTER MIDNIGHT...NOT SEEING MUCH SURFACE
PRESSURE GRADIENT INCREASE UNTIL CLOSER TO NOON ON THURSDAY. THE
RAP/HRRR HAVE INDICATED LIGHT SURFACE WINDS THROUGH MID-MORNING
ALONG WITH HIGH LOW LEVEL MOISTURE (AND VISIBILITIES 1/4 MILE OR
LESS). FOR THESE REASONS...HAVE ISSUED A DENSE FOG ADVISORY FOR
THIS AREA UNTIL 10AM THURSDAY. WE HAVE RECEIVED A FEW REPORTS OF
DENSE FOG ALREADY...AND DO NOT EXPECT CONDITIONS TO IMPROVE
ANYTIME SOON.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 345 PM CDT WED OCT 30 2013
CHALLENGES FOR THE FORECAST INCLUDE TEMPS AND ENDING TIME OF THE
DRIZZLE/LIGHT RAIN OVERNIGHT INTO TOMORROW MORNING. MODELS IN FAIR
AGREEMENT WITH THIS PERIOD AND WILL USE A BLEND FOR THE FORECAST.
THIS EVENING WILL CONTINUE TO SEE VERY WEAK LOW LEVEL MOISTURE/TEMP
ADVECTION IN THE SE THIRD OF THE FA. TOWARD 06Z 850MB WINDS
INCREASE AND BECOME S TO SWERLY. ALSO SFC WINDS WILL TURN TO THE
WEST ALTHOUGH REMAIN LIGHT. DID ADD A MENTION OF PATCHY FOG
OVERNIGHT WITH SATURATED AIRMASS AND THE FOG OCCURRENCE THE PAST
COUPLE NIGHTS UNDER THE HIGHER DEW POINT AIR...DEWPOINTS IN THE
LOW TO MID 30S SEEMS TO BE ENOUGH FOR DEVELOPMENT. THIS MAY DELAY
THE TIMING OF EROSION OF THE LOW LEVEL MOISTURE AND STRATUS DECK
THURSDAY MORNING. BY MIDDAY THURSDAY 500MB UPPER WAVE AND WILL BE
CENTERED OVER THE FAR EASTERN FA WITH NW SFC WINDS AND SOMEWHAT
DRIER AIR...ALTHOUGH MIXING STILL NOT IMPRESSIVE IN THE
LEAST...SHOULD SEE CLOUDS BEGINNING TO SCATTER OUT. WILL GO WITH
HIGHS IN THE LOW TO MID 40S.
THURSDAY NIGHT INTO FRIDAY PRESSURE GRADIENT INCREASES WITH
AN INCREASE IN CLOUDS AS THE NEXT CLIPPER SYSTEM APPROACHES.
CLOUDS AND INCREASED MIXING WILL KEEP LOW TEMPS UP INTO THE LOW
30S.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 345 PM CDT WED OCT 30 2013
THE NEXT SHORTWAVE WILL DROP INTO THE REGION ALONG THE 500MB NW
FLOW FRIDAY. THERMAL COLUMN REMAINS WARM ENOUGH TO SUPPORT ALL
LIQUID PTYPE WITH ANY SHOWER ACTIVITY THAT DOES DEVELOP ALONG
FROPA OR UNDER COLD POOL ALOFT. BEHIND FROPA WINDS WILL BE STRONG
AS 30KTS OR SO IS AVAILABLE TO MIX DOWN FROM 850MB FRIDAY AFTERNOON.
CYCLONIC FLOW MAY KEEP CLOUDS OVER THE AREA FRIDAY NIGHT INTO
SATURDAY AS SFC HIGH AND UPPER TROUGH SLIDE EAST WITH RETURN
SOUTHERLY SFC FLOW DEVELOPING SATURDAY AFTERNOON.
SUNDAY TO WEDNESDAY...SFC LOW WILL GO JUST NORTH OF THE
INTERNATIONAL BORDER GIVING SOME CHANCE FOR MOSTLY LIQUID PRECIP
ALONG THE NRN TIER OF COUNTIES. COOLER AIR WILL MOVE IN BEHIND FOR
A POSSIBLE RA/SN MIX OF LIGHT PRECIP SUN NIGHT IN THE FAR NORTH.
NOT MUCH WRAP AROUND PRECIP WITH THIS EVENT AS SFC-UPPER LOW REMAIN
FAR ENOUGH NORTH. 12Z EURO CAME IN A BIT FARTHER SOUTH HOWEVER SO
WILL NEED TO WATCH FOR ANY SOUTHWARD ADJUSTMENT WHICH WOULD MEAN
HIGHER POPS IN THE NORTH. OTHERWISE A 500 MB SHORT WAVE WILL DROP
INTO THE 4 CORNERS REGION AND THEN MOVE NORTHEAST. MODELS DIFFER
ON TRACK AND TIMING BUT OVERALL SHOW SYSTEM COMING OUT AS A
POSITIVE TILT AND FAIRLY WEAK LOW MONDAY INTO EARLY TUESDAY. SOME
LIGHT MIXED PRECIP MON- TUE WITH THIS...WITH TRACK OF SYSTEM
INDICATING BRUNT MAY BE TO OUR EAST AND SOUTH. 12Z GFS HOWEVER IS
A BIT STRONGER AND COLDER AND WOULD SIGNAL MORE WINTRY PRECIP THAN
THE ALL BLEND TOOL USED FOR THE FORECAST WOULD INDICATE. HIGH
PRESSURE BUILDS IN BY WED WITH A SEASONABLY CHILLY AIRMASS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1148 PM CDT WED OCT 30 2013
IFR/MVFR CIGS ACROSS THE REGION WILL ONLY SLOWLY CLEAR FROM WEST
TO EAST THROUGH THE PERIOD. USED THE RAP GUIDANCE FOR HEIGHT AND
TIMING PURPOSES AS IT APPEARS TO HAVE A GOOD HANDLE ON THE CURRENT
SITUATION.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...DENSE FOG ADVISORY UNTIL 10 AM CDT THURSDAY FOR MNZ015>017-
022>024-027-028-030>032-040.
&&
$$
UPDATE...TG
SHORT TERM...JK
LONG TERM...JK/RIDDLE
AVIATION...TG
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
322 AM EDT THU OCT 31 2013
.SYNOPSIS...
WARM SOUTHERLY WINDS TODAY. COLD FRONT TONIGHT WITH GUSTY SHOWERS.
COOLER FOR THE WEEKEND...WITH A REINFORCING FRONT SATURDAY. HIGH
PRESSURE LATE IN THE WEEKEND AND EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
NOT MUCH CHANGE IN PREV FCST THINKING REGARDING MUCH ADVERTISED SYS
TO AFFECT THE AREA THIS HALLOWEEN NIGHT. THERE IS SOME CONCERN FOR
SOME -SHRA TO MOVE THRU BY EARLY AFTN AS RUC AND ESPECIALLY HRRR
SHOWS SOME MID LVL FORCING IN WAA MOVING ACROSS. DIDNT GET TOO
CARRIED AWAY WITH THIS GIVEN STRONG DOWNSLOPING FLOW AMID DRY LLVLS
BUT ALLOWED FOR CHC POPS W OF THE MTNS WITH SOME LKLY FOR SE OH. MAY
END UP INCREASING POPS MORE W LOWLANDS/NE KY AND ESPECIALLY SE OH
FOR THIS AFTN SHOULD THESE TRENDS IN MDLS CONT.
THE MAIN SHOW STILL LOOKS TO BE WITH PREFRONTAL BAND THIS EVE AND
THEN FRONTAL ACTION. IT IS LOOKING LIKE TRICK OR TREATERS WILL GET
WET IN SE OH AND NE KY...PERHAPS EVEN W LOWLANDS. NOT SURE HOW
STRONG PREFRONTAL BAND IS ONCE INTO AREA THIS EVE GIVEN LACK OF
INSTABILITY...BUT SE OH STANDS BEST SHOT OF SEEING LOW TOPPED QLCS
BEFORE PROBABLY WEAKENING AS IT PUSHES E. ACTUAL COLD FRONT LOOKS TO
ENTER SE OH ARND 06Z...CROSSING OH RVR BY 09Z...AND EXITING MTNS
ARND 12Z. EXPECT A DECENT FRONTAL BAND WITH BAROCLINIC ZONE. DESPITE
LACK OF ANY INSTABILITY...LEFT SOME LOW THUNDER CHC IN...GIVING A
NOD TO STRONG LLJ AND UPR TROF TRYING TO GO NEG TILT.
THIS ALL LEADS TO THE WIND CONCERN. SPC CONT TO KEEP SVR SLIGHT RISK
W OF AREA. STILL...THERE IS CONCERN FOR CONVECTIVE TYPE FRONTAL SHRA
TO BRING DOWN SOME OF THAT 70 KT LLJ TO SFC. AFTER SOME COORDINATION
WITH SOME OF THE SURROUNDING OFFICES FELT PRUDENT TO HANDLE THIS
WITH A WIND ADV FOR ALL OF THE MOUNTAINOUS CO INCLUDING SW VA GIVEN
THESE ARE SYNOPTIC WINDS. HELD OFF ON ANYTHING OUTSIDE OF THE MTNS
AS NOT AS CONFIDENT ON SEEING CRITERIA GUSTS EVEN WITH ANY STOUT
FRONTAL SHRA. STILL EXPECT SOME 35 TO 40 MPH GUSTS THOUGH. NOT
EXPECTING THE STRONG GUSTS DURING THE DAYLIGHT HRS...UNLESS THIS SYS
SPEEDS UP. HARD TO GET STRONG GUSTS ON WAA WITHOUT SOME HELP FROM
CONVECTIVE SHRA...ESPECIALLY WITH WHAT WILL PROBABLY BE AN OVC SKY
OF MID AND HI CLDS.
FOR TEMPS...ELECTED TO GO CLOSER TO COOLER SIDE OF GUIDANCE TDY WITH
ALL THE CLDS AND MAYBE SOME SHRA IN AFTN W ZONES. STILL HAVE UPR 60S
TO LWR 70S FOR MUCH OF THE AREA ON STRONG DOWNSLOPE FLOW AND WAA.
TONIGHTS NUMBERS LOOKED GOOD FROM PREV FCST AND ONLY NEEDED SOME
TWEAKING TO ACCOUNT FOR FALLING TEMPS LATE IN SE OH/NE KY POST
FRONTAL AND IMPROVING SKY.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
MOST MODELS SHOWING DEEPER MOISTURE FROM THE COLD FRONT MOVING AWAY
QUICKLY FRIDAY MORNING. NAM IS AN OUTLIER HERE...AS IT DEVELOPS A
WAVE ALONG THE FRONT AND SKIRTS THE EASTERN COUNTIES. THE
ECMWF...GFS...AND CANADIAN ARE ALL SHOWING THE WAVE MUCH FURTHER
EAST. WILL DISCOUNT THE HANDLING OF THIS WAVE BY THE NAM.
MOS HIGHS ON FRIDAY ARE STILL LOOKING WAY TOO WARM BASED ON 850 MB
TEMPERATURES AND BEING BEHIND THE COLD FRONT. WILL CONTINUE TO
UNDERCUT CONSIDERABLY.
A STRONG TROUGH MOVES THROUGH ON SATURDAY...PROVIDING A REINFORCING
COLD FRONT. MODELS ARE DIVIDED ON TIMING OF PRECIPITATION AND HOW
MUCH. WILL STAY NEAR CURRENT FORECAST FOR NOW...AS THIS APPEARS TO
BE A GOOD MIDDLE GROUND.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
COLD SYSTEM EXITING THE AREA AT THE START OF THE PERIOD...WARM
SYSTEM MOVING IN AT THE END...WITH HIGH PRESSURE LARGE AND IN CHARGE
IN BETWEEN.
PERIOD BEGINS WITH LOW LEVEL COLD ADVECTION IN W TO NW FLOW BENEATH
UPPER LEVEL SHORT WAVE/ LONG WAVE TROUGH RIGHT OVER THE AREA. HAVE
UPSLOPE SNOW SHOWERS TAPERING OFF OVERNIGHT INTO FIRST THING SUN
MORNING...BUT WITH A SWITCH TO SNOW SHOWERS EARLY ON OVER THE HIGH
TERRAIN...THE SNOW LEVELS LOWERING AS THE PRECIPITATION WINDS DOWN.
AS THE CLOUD TOPS LOWER AND WE LOSE CRYSTAL GROWTH...PRECIPITATION
MAY END BEFORE A SWITCH OVER AT LOCATIONS LIKE EKN AND BKW.
AFTER THE COLD START...THE WEATHER WARMS UP EARLY NEXT WEAK AS THE
L/W TROUGH POSITION SHIFTS QUICKLY E...AND A L/W RIDGE AXIS BECOMES
ESTABLISHED ALONG THE E COAST BY THE END OF THE PERIOD. LARGE SFC
HIGH PASSES N OF THE AREA EARLY MON BUT SFC RIDGING DOWN THE E SIDE
OF THE APPALACHIANS PERSISTS INTO WED. LOW LEVEL MOISTURE IN THE
LONG ATLANTIC FETCH S OF THE LARGE HIGH WILL LIKELY INTRODUCE CLOUDS
TO THE EASTERN SLOPES BY TUE. MEANWHILE...LONG FETCH UPPER LEVEL SW
FLOW FROM NORTHERN MEXICO SHOULD CARRY MID AND HIGH CLOUD INTO THE
AREA BEGINNING TUE AS WELL.
HAVE THE CHANCE FOR RAIN SHOWERS STARTING WED...AT FIRST ALONG THE
EASTERN SLOPES AND IN THE W WITH THE TYPICAL S FLOW SHADOW ACROSS
THE MIDDLE OF THE CWA THAT THEN GRADUALLY FILLS IN WED NT. WITH WPC
BEING SLOWER WITH THE FRONT THAN EVEN THE SLOWER ECMWF...KEPT THE
FRONT W OF THE AREA THROUGH THE END OF THE PERIOD...12Z THU...THE
GFS HAS THE FRONT ABOUT HALF THE WAY THROUGH THE CWA AT THAT TIME.
THE 12Z ECMWF ADDED A NEW TWIST...WITH A MUCH STRONGER UPPER LEVEL
HIGH OVER THE SERN STATES KEEPING THE FRONT FROM REACHING ALL BUT
PERHAPS NORTHERN PORTIONS OF THE AREA ALMOST ALL THE WAY THROUGH ITS
240 HR RUN.
USED MOSTLY AN ECE/WPC BLEND FOR TEMPERATURES WITH THE MEX ALSO
BLENDED IN FOR LOWS EARLY ON. LEANED TOWARD HIGHER GUIDANCE LATE IN
THE PERIOD IN THE MILD STRONG S FLOW AHEAD OF THE FRONT OUT TO THE W.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
06Z THURSDAY THRU 06Z FRIDAY...
MAINLY VFR CONDITIONS THROUGH EARLY AFTN WITH A BKN TO OVC DECK OF
MID/HI CLDS. CIGS LWR LATE THIS AFTN AND INTO THIS EVE AS PREFRONTAL
SHRA WORK IN FROM W. MVFR CIGS WILL OVERSPREAD SE OH AFTER 21Z AND
TAKING UNTIL PERHAPS 06Z ELSEWHERE...GIVEN STRONG LLVL DOWNSLOPING
FLOW. SFC FRONT TO MAKE INROADS INTO SE OH BY 06Z...CROSSING OH RVR
BY 09Z...AND EXITING MTNS ARND 12Z. SOME IFR CIGS/VSBY POSSIBLE WITH
PREFRONTAL BAND AND ACTUAL FRONTAL BAND. S TO SW FLOW ALOFT WILL BE
INCREASING TDY WHICH MAY LEAD TO A FEW HRS OF LLWS CONCERNS FOR
LOWLAND TAF SITES. HELD OFF IN THE 06Z ISSUANCE AND WILL REEVALUATE
FOR THE 09Z AMENDMENT. WITH EXPECTED OVC SKY TDY AND WAA NATURE TO
FLOW...THINK WIND GUSTS WILL BE HELD IN CHECK ACROSS THE
TERMINALS...GENERALLY LESS THAN 20 KTS DESPITE APPROACHING LLJ. DID
INCREASE THE GUSTS TONIGHT TO NEAR 30 KTS. MTN SITES COULD GUST
HIGHER BY 06Z BUT DID NOT WANT TO GET TOO CARRIED AWAY AT THIS
DISTANCE AS IT WILL PROBABLY TAKE STOUT CONVECTIVE SHRA TO BRING
DOWN THE STRONGER WINDS. HAVE OH RVR SITES LOSING POST FRONTAL
STRATUS BY 12Z WITH A DRYING COLUMN. ALSO LET GUSTS SUBSIDE AFTER
FROPA.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATIVE SCENARIOS: WINDS MAY NOT BE AS GUSTY TDY. TIMING OF SHRA
MAY VARY HEADING INTO LATE THIS AFTN AND EARLY EVE.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE THU 10/31/13
UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19
EDT 1HRLY 04 05 06 07 08 09 10 11 12 13 14 15
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY M L L L L H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z FRIDAY...
IFR POSSIBLE IN THE HIGHER ELEVATIONS OF THE MOUNTAINS SATURDAY
NIGHT INTO EARLY SUNDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...WIND ADVISORY FROM 6 PM THIS EVENING TO 7 AM EDT FRIDAY FOR
WVZ033>038-046-047.
OH...NONE.
KY...NONE.
VA...WIND ADVISORY FROM 6 PM THIS EVENING TO 7 AM EDT FRIDAY FOR
VAZ003-004.
&&
$$
SYNOPSIS...TRM/RPY/30
NEAR TERM...30
SHORT TERM...RPY
LONG TERM...TRM
AVIATION...SL
AREA FORECAST DISCUSSION
NWS NORMAN OK
1154 PM CDT WED OCT 30 2013
.AVIATION...
STRONG TO OCCASIONALLY SEVERE GUSTS WILL BE POSSIBLE WITH
A THIN LINE OF CONVECTION THAT IS CURRENT LOCATED IN WESTERN
OKLAHOMA. GUSTS WILL BE FROM THE SOUTHWEST AND WEST. MOST OF THIS
CONVECTION SHOULD BE EAST OF ALL TAF SITES BY 10-11Z.
MEANWHILE...IFR CEILINGS IN CENTRAL OKLAHOMA SHOULD IMPROVE AFTER
THE STORMS AND RAIN MOVE EAST. COLD FRONT IN NORTHERN OKLAHOMA
WILL CONTINUE TO SAG SOUTHWARD TONIGHT...BUT WILL GET A MUCH
STRONGER PUSH AFTER SUNRISE THURSDAY.
&&
.PREV DISCUSSION... /ISSUED 652 PM CDT WED OCT 30 2013/
AVIATION...
STORMS HAVE STRUGGLED TO DEVELOP OR STRENGTHEN. BETTER CHANCES
FOR DEVELOP SHOULD ARRIVE LATER THIS EVENING AND OVERNIGHT AS
BETTER LIFT ARRIVES. MEANWHILE...IFR CEILINGS TO NEAR MFVR
CEILINGS WILL PREVAIL ACROSS CENTRAL OKLAOMA WITH MVFR CEILINGS
DEVELOPING ELSEWHERE.
A COLD FRONT WILL BRING A STRONG WIND SHIFT ON WEDNESDAY
WITH VFR CEILINGS. RECENT HRRR RUN IS FASTER WITH PUSHING
THE COLD FRONT SOUTHWARD THIS EVENING AS THIS IS PREFERRED.
PREV DISCUSSION... /ISSUED 406 PM CDT WED OCT 30 2013/
DISCUSSION...
WIDELY SCATTERED SHOWERS CONTINUE ACROSS PORTIONS OF EASTERN AND
SOUTHERN OK...WITH AN INITIAL SHORTWAVE TROUGH EXITING THE
REGION. A FEW STRONGER STORMS HAVE MANAGED TO DEVELOP ALONG THE
FRONT IN KS...BUT HAVE STRUGGLED TO MAINTAIN THEIR INTENSITY WITH
LITTLE MLCAPE IN PLAY. HIGHER INSTABILITY IS PRESENT NEAR THE
PREFRONTAL TROUGH/DRYLINE ACROSS SW OK AND W N TX. EXPECT SOME
DEVELOPMENT NEAR THERE AS ANOTHER WEAK MID LEVEL SHORTWAVE TROUGH
(SIGNS OF LIFT NOW EVIDENT ACROSS WESTERN N TX) WITHIN SW FLOW
MOVES OVERHEAD COMBINING WITH SOME ENHANCED SURFACE CONFLUENCE.
SOME HAIL MAY ACCOMPANY THE STRONGER STORMS...BUT POOR MID LEVEL
LAPSE RATES AND MARGINAL INSTABILITY MAY KEEP AT OR JUST BELOW
SEVERE LIMITS. LATER TONIGHT RAPID HEIGHT FALLS WILL OVERSPREAD
THE REGION WITH THE APPROACH OF THE UPPER TROUGH LIKELY RESULTING
IN MORE DEVELOPMENT PARTICULARLY ACROSS CENTRAL AND NORTHERN OK.
HEAVY RAINFALL ALSO APPEARS LIKELY OVER EXTREME SE OK. THE FRONT
AND MID LEVEL TROUGH AXIS BOTH APPEAR TO HAVE SLOWED SO WILL
LINGER AT LEAST SCHC POPS ACROSS THE EASTERN HALF OF THE FA...AND
SOME CHC POPS ACROSS THE NORTH ASSOCIATED WITH THE DPVA AS THE LOW
MOVES OVER THIS REGION.
THE 700MB TROUGH AXIS WILL FINALLY PASS OVER THE I35 CORRIDOR JUST
BEFORE LUNCHTIME AND RAPID CLEARING WILL FOLLOW. WINDS WILL
INITIALLY INCREASE BEHIND THE FRONT WITH MIXING...BUT DECOUPLE
QUICKLY WITH SUNSET. LOWS WILL DROP MAINLY BACK INTO THE 40S
FRIDAY. THE ANOTHER SHORTWAVE TROUGH WILL DIG SOUTHWARD FRIDAY
MORNING TRAVERSING THE LEE OF THE ROCKIES AND SWINGING ANOTHER MID
TO UPPER TROUGH AXIS ACROSS THE SOUTHERN PLAINS AND MIDWEST. A
COLDER AIRMASS WILL ACCOMPANY THIS TROUGH WITH A ~1025 HIGH IN
PLACE OVER THE LEE OF THE ROCKIES BY SAT MORNING. THIS WILL DROP
TEMPS BACK INTO THE LOW 40S AND UPPER 30S WITH SOME FREEZING
POSSIBLE CLOSER TO THE CENTER OF THE HIGH OVER NW OK. THESE COLDER
THAN NORMAL TEMPS WILL STICK AROUND UNTIL EARLY NEXT WEEK WHEN
RETURN FLOW ESTABLISHES ITSELF AHEAD OF A DIGGING MID TO UPPER
TROUGH OVER THE ROCKIES. RAIN CHANCES WILL RETURN INTO THE
EXTENDED AS MOISTURE INCREASES AHEAD OF THIS FEATURE. THE HIGHEST
CHANCES APPEAR TO BE TUESDAY WHEN A STRONG COLD FRONT IMPACTS THE
REGION.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 63 67 45 71 / 60 20 0 0
HOBART OK 59 69 45 70 / 30 10 0 0
WICHITA FALLS TX 63 72 46 75 / 60 10 0 0
GAGE OK 47 66 38 67 / 20 10 0 0
PONCA CITY OK 54 65 41 67 / 80 40 0 0
DURANT OK 64 75 50 76 / 90 20 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PORTLAND OR
856 PM PDT WED OCT 30 2013
.SYNOPSIS...A WEAK FRONT WILL BRING RAIN SHOWERS AND DRIZZLE TO THE
REGION TONIGHT INTO THURSDAY. HIGH PRESSURE WILL BRING DRIER WEATHER
TO THE REGION FRIDAY. A STRONGER STORM SYSTEM SATURDAY WILL BRING
BREEZY CONDITIONS ALONG THE COAST...VALLEY RAIN AND MOUNTAIN SNOW.
DRIER WEATHER SHOULD RETURN LATE IN THE WEEKEND INTO EARLY NEXT
BEFORE ANOTHER SERIES OF EVEN COLDER STORM SYSTEMS POSSIBLY IMPACT
THE REGION DURING THE MIDDLE TO LATTER PART OF NEXT WEEK.
&&
.EVENING UPDATE...A LOOP OF DOPPLER RADAR SHOWS WIDESPREAD ECHOES
SPREADING SOUTHEASTWARD OVER THE CWA THIS EVENING. THIS IS RESPONSE
TO ISENTROPIC LIFT NEAR THE 295K SURFACE. WHILE THE INITIAL RETURNS
ARE VIRGA...A GRADUAL MOISTENING OF THE ATMOSPHERE IS UNDERWAY WITH
MEASURABLE RAIN REPORTED IN THE COAST RANGE...AND TRACES ARE
BEGINNING TO SHOW UP FURTHER INLAND AT KSPB AND KMMV. AS A
RESULT...SPRINKLES WERE ADDED TO THE FORECAST THROUGH 06Z. BOTH THE
GFS AND NAM SUGGEST THIS ISENTROPIC LIFT WILL CONTINUE THROUGH 12Z.
AS A RESULT...POPS HAVE BEEN INCREASED AND EXPANDED IN AREAL
COVERAGE FOR THE 06Z-12Z PERIOD.
A WEAK SURFACE TROUGH STILL WEST OF BUOY 89 WILL MOVE INTO THE COAST
THURSDAY MORNING. THIS SHOULD PROVIDE A SECONDARY FOCUS FOR SHOWERS
THURSDAY MORNING AND EARLY AFTERNOON AS IT PUSHES INLAND AND FALLS
APART. SHORTWAVE RIDGING STILL LOOKS ON TRACK TO BRING DRIER
CONDITIONS TO THE AREA THURSDAY NIGHT AND FRIDAY...WITH PERHAPS SOME
MORNING FOG.
THE WEEKEND FORECAST STILL LOOKS INTERESTING...BUT MODELS CONTINUE TO
WAVER ON THE POSITION AND STRENGTH OF A DEVELOPING LOW PRESSURE THAT
WILL MOVE INTO THE PACIFIC NORTHWEST LATE FRIDAY INTO SATURDAY. THE
NAM REMAINS THE WEAKEST AND FURTHEST SOUTH. MEANWHILE...THE LATEST
GFS BRINGS A 999MB LOW PRESSURE INTO THE OLYMPIC PENINSULA. THE 12Z
EC REMAINS A HYBRID OF THE TWO. INTERESTINGLY...MODELS GENERALLY DO
NOT SEEM VERY AMBITIOUS TO INCREASE PREFRONTAL WINDS. THE GFS
SOLUTION WOULD BRING A SWATH OF STRONGER POST FRONTAL WINDS FOR THE
FAR NORTH OREGON COAST AND WASHINGTON COAST...BUT ON A COUPLE OF
EVENTS IN THE PAST YEAR OR SO...THE MODELS HAVE OVERDONE THESE
POSTFRONTAL WINDS. AS A RESULT...CONFIDENCE IS NOT TERRIBLY HIGH
THAT 45 TO 55 MPH WINDS WILL SURFACE ALONG THE COAST EVEN IF THE GFS
SOLUTION WERE TO PAN OUT. HOWEVER...DUE TO THE INHERENT
UNCERTAINTY...I WILL NOT MAKE ANY CHANGES TO THE SPS CURRENTLY OUT
FOR THE COAST...AND WILL LET THE MID SHIFT TAKE IN THE 00Z EC.
THE OTHER NOTABLE IMPACT FROM THIS SYSTEM WILL BE SNOW LEVELS
LOWERING TO NEAR 3000 TO 3500 FT WITH ACCUMULATING SNOW LIKELY. AT
THIS POINT...IT LOOKS LIKE THE HEAVIEST PRECIPITATION WILL FALL
BEFORE SNOW LEVELS DROP BELOW 5000 FT SATURDAY. NONETHELESS...WEST
TO NORTHWEST 30 TO 40 KT 850MB FLOW WILL ACT ON A DEEP CONDITIONALLY
UNSTABLE AIRMASS TO PRODUCE AMPLE SHOWERS OVER THE CASCADES SATURDAY
AFTERNOON INTO EARLY SUNDAY. AS A RESULT...MOTORISTS SHOULD BE PREPARED
FOR WINTER LIKE DRIVING CONDITIONS OVER WILLAMETTE AND SANTIAM
PASSES AND AROUND GOVERNMENT CAMP ALONG HIGHWAY 26 SATURDAY
AFTERNOON INTO EARLY SUNDAY. /NEUMAN
.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY.
THE LOW PRESSURE SYSTEM WILL EXIT THE REGION SUNDAY THOUGH SOME
SHOWERS WILL PERSIST BEHIND THE FRONT WITH THE ONSHORE NEAR-SURFACE
FLOW. SNOW SHOULD CONTINUE IN THE CASCADES SUNDAY ALONG WITH SOME
WINDY CONDITIONS. SNOW LEVELS WILL DROP TO AROUND OR JUST BELOW 3000
FT SUNDAY AS COOL NORTHWESTERLY FLOW ALOFT BUILDS OVER THE PACIFIC
NORTHWEST. SOME SHORTWAVE ENERGY WILL ENHANCE SHOWER CHANCES EARLY
NEXT WEEK AND THE NEXT SYSTEM SHOULD TUESDAY. WHILE THE FORECAST
MODELS EXHIBIT SOME VARIATIONS WITH RESPECT TO THE FINER DETAILS OF
TIMING PERIODS OF PRECIPITATION THROUGH THE MIDDLE OF NEXT WEEK...IT
IS CLEAR THAT WE ARE SHIFTING TO A MORE SEASONAL TYPE OF PATTERN.
HIGHS TEMPERATURES WILL BE NOTICEABLY COOLER FOR THE FIRST HALF OF
NEXT WEEK...AND MAX AND MIN TEMPERATURES SHOULD EACH RUN SEVERAL
DEGREES BELOW NORMAL THROUGH THE PERIOD. CULLEN
&&
.AVIATION...MOSTLY MID LEVEL CLOUDS GREATER WITH BASES HIGHER THAN
5000 FEET RESULTING IN A FEW SPRINKLES THIS EVENING AND TONIGHT
THOUGH REMAINING VFR. EXPECT ENOUGH LIFT WITH THE FRONT TO LOWER
CIGS TO 5000 FT OR LOWER OVERNIGHT....WITH MVFR CONDITIONS
POSSIBLE AT THE COAST. MVFR BECOMES INCREASINGLY POSSIBLE FOR THE
INLAND TERMINALS AFTER DAYBREAK OR LATER THU MORNING WITH LIGHT
RAIN OR DRIZZLE. HIGHEST CONFIDENCE FOR MVFR WILL BE LATE MORNING
TO EARLY AFTERNOON. WITH THE ABUNDANT LOWER LEVEL MOISTURE
ARRIVING...IFR CONDITIONS ARE POSSIBLE. THE COLD FRONT PASSAGE
OCCURS LATER IN THE AFTERNOON WHICH SHOULD HELP TO SCOUR OUT LOWER
CIGS...BUT LIGHT FLOW WILL BRING IFR POTENTIAL THU NIGHT.
KPDX AND APPROACHES...VFR WILL PREVAIL THROUGH AT LEAST 12Z THU.
LIGHT RAIN OR DRIZZLE MAY DEVELOP AROUND 12Z FOR A THREAT OF MVFR.
THE WARM-FRONTAL NATURE OF THE INCOMING SYSTEM COULD ALSO LEAD TO
IFR OR LOW-END MVFR THU MORNING. KMD
&&
.MARINE...WEAK FRONTAL SYSTEM WILL CONTINUE TO BRING WIND GUSTS OF
20-25 KT TONIGHT. THE LATEST HRRR SUGGESTS THE FRONT HANGS UP LONG
ENOUGH TO SUGGEST THESE WINDS WILL HANG ON A BIT LONGER...AT LEAST
FOR THE WATERS CLOSER TO SHORE...SO EXTENDED THE SMALL CRAFT
ADVISORY THROUGH DAYBREAK. CANNOT RULE OUT A FEW GUSTS ALONG THE
CENTRAL OREGON COASTAL INNER WATERS TO 25 KT THOUGH CONFIDENCE IS
LOW. /KMD
REST OF THE MARINE DISCUSSION UNCHANGED...A MUCH STRONGER SYSTEM WILL
IMPACT THE WATERS LATE FRIDAY NIGHT AND SAT. STILL PLENTY OF MODEL
DISCREPANCY WITH THE TRACK AND CENTRAL PRESSURE OF THE LOW. THE
18Z NAM IS MUCH WEAKER AND A BIT MORE S WITH IT COMPARED TO THE
12Z RUN. THE 18Z VERSION SHOWS A 1012 MB CENTER NEAR CAPE FALCON
09Z SAT. THE 12Z RUN WAS NEAR 1000 MB AND FURTHER N. 12Z GFS AND
ECMWF ARE SOMEWHAT SIMILAR WITH THE CENTRAL PRES...1002 MB OR
SO...BUT THE GFS SHOWS LANDFALL ALONG NEAR VANCOUVER ISLAND. THE
ECMWF TRACK IS BETWEEN THE 18Z NAM AND THE 12Z GFS. IN ANY
EVENT...LOOK FOR GALES TO DEVELOP OVER THE WATERS EARLY SAT
MORNING AND CONTINUE THROUGH THE AFTERNOON. THE POST-FRONTAL W-NW
WIND COULD BE JUST AS STRONG...IF NOT A BIT STRONGER...THAN THE
PRE-FRONTAL WIND. THERE IS THE POTENTIAL FOR SOME STORM-FORCE
GUSTS OVER THE FAR N WATERS. THE WIND SETTLES DOWN FAIRLY QUICKLY
SAT EVENING.
SEAS REMAIN WELL BELOW 10 FT THROUGH FRI NIGHT...BUT MAKE A
SUBSTANTIAL JUMP SAT MORNING. EXPECT 15-20 FT SEAS SAT
MORNING...WIND-WAVE DOMINATED. COULD SEE HIGHER SEAS SHOULD THE GALE-
FORCE NWLY WIND END UP STRONGER AND OF LONGER DURATION OVER THE
FETCH AREA. W-NW SWELL AROUND 20 FT IMPACTS THE FAR N WATERS SAT
AFTERNOON. WEISHAAR
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 7 AM PDT THURSDAY FOR
COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR
OUT 10 NM-WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR
FROM 10 TO 60 NM.
&&
$$
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 FORT WORTH TX
1141 PM CDT WED OCT 30 2013
.AVIATION...
THUNDERSTORMS HAVE LINED UP OVER SOUTH AND SOUTHEAST COUNTIES OF
NORTH TEXAS...WHERE THEY WILL LIKELY REMAIN FOR SEVERAL MORE HOURS
BEFORE MOVING EAST OF THE REGION. THIS SHOULD KEEP THE BRUNT OF THE
CONVECTION EAST OF NORTH TEXAS TAF SITES DURING THE OVERNIGHT
HOURS. THE NORTHWEST EDGE OF THIS AXIS OF CONVECTION IS RIGHT AT
THE MCLENNAN COUNTY LINE...SO WE WILL NEED TO KEEP A CLOSE EYE ON
KACT IN CASE THE SOUTHWEST EDGE OF THE THUNDERSTORMS DECIDE TO
LIFT NORTH TOWARDS THE FIELD.
WE STILL EXPECT INCREASING RAIN SHOWERS WITH ISOLATED
THUNDERSTORMS AT THE METROPLEX TAF LOCATIONS AS THE UPPER TROUGH
TO OUR WEST APPROACHES ALONG WITH A PACIFIC COLD FRONT. SINCE IT
APPEARS CONVECTION SHOULD REMAIN MORE ISOLATED IN NATURE...WILL
LIKELY GO WITH A VCTS DURING THE 09-12Z TIME FRAME AT ALL
LOCATIONS. THE MESOSCALE BOUNDARY FROM EARLIER IN THE EVENING
NEVER QUITE MADE IT NORTH OF THE METROPLEX...WHICH KEPT THE IFR
CIGS IN PLACE. CLOUD BASES MAY LIFT A LITTLE AS WINDS SLOWLY VEER
BUT DO NOT EXPECT SIGNIFICANT IMPROVEMENT UNTIL WINDS BECOME
SOUTHWEST AROUND SUNRISE IMMEDIATELY AHEAD OF THE FRONT.
WEST WINDS BEHIND THE FRONT SHOULD CONTINUE VEERING TO A
NORTHWESTERLY DIRECTION BY EARLY AFTERNOON THURSDAY. WIND SPEEDS
AROUND 20 KTS WILL LIKELY PRODUCE SOME CROSS WIND ISSUES AT DFW DURING
THE LATE MORNING HOURS BEFORE MORE OF A NORTHWESTERLY COMPONENT IS
REACHED 18-19Z. SPEEDS WILL DROP OFF AS LOW LEVEL WINDS DECOUPLE
SHORTLY AFTER SUNSET.
30
&&
.UPDATE...
AT THE SURFACE AN EFFECTIVE WARM FRONT BOUNDARY DEVELOPED TODAY
AND IS CURRENTLY LOCATED ALONG A LINE FROM NACOGDOCHES TO MEXIA TO
GRANBURY TO WICHITA FALLS. TO THE NORTH OF THIS BOUNDARY
TEMPERATURES AND DEWPOINTS ARE IN THE MID 60S...ABOUT 5 TO 7
DEGREES COOLER THAN THE AIRMASS TO THE SOUTH OF THE BOUNDARY. EVEN
SHORT TERM MODEL GUIDANCE HAS NOT REALLY CAUGHT ONTO THE PRESENCE
OF THIS BOUNDARY...WHICH IS AFFECTING THE FORECAST SURFACE
INSTABILITY FIELDS OVER THE NORTHEAST HALF OF THE REGION. IN
ADDITION...HAVE LOWERED FORECAST LOW TEMPS 5 DEGREES OR SO TO NEAR
CURRENT TEMPS IN THIS AREA. TEMPERATURES WILL BE STEADY OR RISE
SLOWLY AS THE WARM FRONT LIFTS NORTH AS THE MAIN UPPER TROUGH AND
SURFACE LOW PRESSURE SYSTEM MOVE EAST TONIGHT.
CONCERNING THE CONVECTIVE FORECAST AND HEAVY RAIN POTENTIAL. THE
RADAR IS CLEARLY SHOWING THE EFFECTS OF A LOW LEVEL TROUGH OR
BOUNDARY THAT HAS SET UP THIS EVENING RIGHT ALONG THE I-35
CORRIDOR SOUTH OF TEMPLE. THE BOUNDARY EXTENDS FROM COTULLA TO
AUSTIN TO MARLIN TO ATHENS. EVENING FWD SOUNDING INDICATED
SIGNIFICANTLY DRIER AIR NEAR 850MB AND MORE VEERED WESTERLY FLOW.
AT DEL RIO...DRY AIR AND EVEN NORTHWEST WINDS WERE PRESENT AT
850MB...SO THERE IS GOOD REASON TO BELIEVE THAT THE LOW LEVEL
BOUNDARY IS FIRMLY IN PLACE AND WILL REMAIN IN TACT THROUGH
TONIGHT ACROSS CENTRAL AND EAST TEXAS. THIS BOUNDARY WILL BE THE
FOCUS FOR TRAINING CONVECTIVE CELLS THROUGH THE NEXT 6 TO 9 HOURS
OVER THE SOUTHEAST ZONES. ALL OF THE INGREDIENTS THAT PORTEND TO
EXCESSIVE RAINFALL ARE AVAILABLE TONIGHT WITH HIGH MOISTURE
CONTENT...STRONG LOW LEVEL WINDS RESULTING IN HIGH MOISTURE
FLUX...WEAK INSTABILITY...AND HIGH FREEZING LEVELS. AM VERY
CONCERNED SOME LOCATIONS ACROSS THE SOUTHEAST ZONES MAY RECEIVE
OVER 6 INCHES OF RAIN TONIGHT...WHICH RAISES CONCERN FOR A
SIGNIFICANT FLASH FLOODING EVENT THAT IS A THREAT TO LIFE AND
PROPERTY.
WITH THE BAND OF CONVECTION SETTING UP IN THIS LOCATION...AND THE
PRESENCE OF DRIER AND MORE STABLE AIR OVER THE NORTHEAST ZONES
HAVE CANCELED THE WATCH OVER THE NORTHEAST ZONES...INCLUDING
ROCKWALL AND KAUFMAN COUNTIES. ADDITIONAL RAIN IS LIKELY IN THESE
AREAS TONIGHT...BUT HEAVY RAIN THREAT IS LESSENING. THE FORT
WORTH SOUNDING DID INDICATE A LAYER OF MOIST/CONDITIONALLY
UNSTABLE PARCELS JUST ABOVE THE COOLER SURFACE LAYER. WHEN THE
NEXT PIECE OF UPPER LEVEL ENERGY THAT IS NOW LOCATED IN NEW MEXICO
ROTATES OUT INTO THE SOUTHERN PLAINS...THIS SHOULD BE CONVERTED
INTO SCATTERED SHOWERS AND STORMS OVER THE REMAINDER OF THE AREA
NORTH OF THE TRAINING BAND OF HEAVY RAINFALL. THIS MAY WAIT UNTIL
THE COLD FRONT ARRIVES LATE TONIGHT AND A SURFACE/LOW LEVEL
TRIGGER BECOMES AVAILABLE. FOR THIS REASON WILL KEEP POPS HIGH
OVER THE AREA...BUT THE THREAT FOR HEAVY RAINFALL WILL BE LIMITED
BY QUICK DURATION AND THE THREAT FOR SEVERE WEATHER WILL BE
LIMITED BY MOIST ADIABATIC LAPSE RATES ALOFT.
TR.92
&&
.PREV DISCUSSION... /ISSUED 401 PM CDT WED OCT 30 2013/
THE NEXT 18 HOURS WILL BE QUITE UNSETTLED ACROSS NORTH TEXAS WITH
PERIODS OF SHOWERS AND THUNDERSTORMS AND THE POTENTIAL FOR BOTH
SEVERE WEATHER AND FLASH FLOODING. WHILE MOST AREAS WILL PICK UP
SOME RAINFALL THROUGH LATE TONIGHT...THE MAIN CHALLENGE WILL BE
NARROWING DOWN THE HIGHEST POTENTIAL FOR HEAVY RAINFALL AND FLASH
FLOODING. THERE ARE A COUPLE OF COMPLICATING FACTORS THAT COULD
HAVE SIGNIFICANT IMPACTS ON THE SHORT TERM FORECAST INCLUDING THE
POTENTIAL FOR UNDERESTIMATING THE SEVERE THREAT.
CONCERNING THE SHORT TERM SEVERE WEATHER THREAT...LATEST SATELLITE
IMAGERY SHOWS SUBSTANTIAL BREAKS IN THE CLOUD COVER ACROSS THE
FAR SOUTHERN PARTS OF THE CWA INTO SOUTHEAST TEXAS. THIS IS
IMPORTANT BECAUSE TEMPERATURES IN HENDERSON AND ANDERSON COUNTIES
ARE IN THE MID 60S WHILE TEMPERATURE ACROSS BELL AND MILAM
COUNTIES ARE IN THE LOWER 80S. THIS DIFFERENTIAL HEATING BOUNDARY
WILL EFFECTIVELY ACT AS A WARM FRONT WITH STRONGLY BACKED WINDS TO
THE NORTH OF THE BOUNDARY. LOCALLY RUN SEVERE PARAMETERS INDICATE
AROUND 2000J/KG OF SURFACE BASED CAPE WITH LITTLE INHIBITION. MORE
IMPORTANTLY...LOW LEVEL TURNING OF THE WINDS IS QUITE STRONG AND
THERE IS AMPLE LOW LEVEL CAPE. GIVEN THE VERY HIGH SURFACE
DEWPOINTS...LCLS ARE LOW AND THIS AREA WOULD NEED TO BE MONITORED
FOR A LOCALLY ENHANCED TORNADO THREAT ESPECIALLY IF STORMS DEVELOP
ALONG THE BOUNDARY ITSELF.
ELSEWHERE...THERE IS A POTENTIAL FOR MORE ISOLATED SEVERE
THUNDERSTORMS THROUGH THE NIGHT ACROSS NORTH TEXAS GIVEN AMPLE
DEEP LAYER SHEAR OF AROUND 50KTS. WITH DEEP MOISTURE IN
PLACE...LAPSE RATES ARE NOT OVERLY STEEP BUT A MARGINALLY SEVERE
HAIL THREAT WOULD EXIST. THERE IS A LAYER OF MID LEVEL DRY AIR
OVER NORTH TEXAS WHICH COULD ENHANCE DOWNDRAFTS LOCALLY SUPPORTING
A LOW END DAMAGING WIND THREAT.
THE MORE SIGNIFICANT HAZARD ACROSS NORTH TEXAS APPEARS TO BE THE
POTENTIAL FOR FLASH FLOODING THROUGH TONIGHT. THE MID LEVEL DRY
AIR MENTIONED ABOVE HAS BEEN A THORN IN OUR SIDE IN TRYING TO
DETERMINE THE LOCATION OF HEAVIEST RAINFALL. MODEL GUIDANCE
CONTINUES TO INDICATE AT LEAST WEAK SUBSIDENCE INCREASING ACROSS
THE WESTERN HALF OF THE CWA THROUGH LATE THIS EVENING. AIRCRAFT
SOUNDINGS FROM DFW AND DAL SHOW THIS LAYER OF DRY AIR FROM ABOUT
700MB TO 550MB. MORE IMPORTANTLY...LATEST SOUNDINGS INDICATE THAT
THIS DRY AIR IS SINKING...IMPLYING DOWNWARD VERTICAL MOTIONS.
LATEST FORECAST WILL FOLLOW THE ASSUMPTION THAT SOME DRIER AIR
WILL REMAIN IN PLACE ACROSS THE WESTERN HALF OF THE CWA...OR MORE
SPECIFIC...FROM SOUTHWEST TO NORTHEAST ACROSS THE CWA FROM NEAR
GOLDTHWAITE TO HILLSBORO TO SHERMAN. THIS WILL BE IN THE FORM OF A
TIGHT THETA-E BOUNDARY ALONG THESE AREAS. AS THE MAIN UPPER LOW
EJECTS EASTWARD LATER TONIGHT LARGE SCALE FORCING WILL CONTINUE TO
INCREASE. THE COVERAGE OF SHOWERS AND THUNDERSTORMS SHOULD
INCREASE DRAMATICALLY AFTER DARK...MAINLY FROM 9PM TO 2AM. THE
AFOREMENTIONED THETA-E BOUNDARY THEN BECOMES ESPECIALLY IMPORTANT
BECAUSE MOST OF THE HEAVY PRECIPITATION WILL BE ALONG AND EAST OF
THIS BOUNDARY. WITH A 50KT LLJ PUMPING RICH MOISTURE INTO THIS
SYSTEM...EXPECT SEVERAL HOURS OF TRAINING SHOWERS AND
THUNDERSTORMS...MAINLY ACROSS THE EAST AND SOUTHEAST COUNTIES. THE
CURRENT FLASH FLOOD WATCH HIGHLIGHTS THE AREAS WHERE WE THINK THE
BEST CHANCE FOR TRAINING THUNDERSTORMS EXISTS. OF COURSE...IF THIS
IS OFF ANY BIT...CONSIDERABLY HEAVIER RAINFALL COULD FALL FARTHER
WEST. THE LAST FEW RUNS OF THE HRRR SEEM TO SUGGEST THAT MUCH
HEAVIER RAINFALL WILL FALL WEST...BUT IT SEEMS TO BE THE OUTLIER
AT THIS TIME AND DOESNT APPEAR TO BE HANDLING THE DRY AIR AS WELL.
THAT BEING SAID...CURRENT FLASH FLOOD WATCH CONFIGURATION WILL
REMAIN THE SAME...BUT IF IT BECOMES APPARENT THAT HEAVIER RAINFALL
WILL OCCUR WEST...WE WILL EXPAND IT THIS EVENING. WITH PWS IN
EXCESS OF 2 INCHES...WHICH IS ANOMALOUSLY HIGH FOR LATE
OCTOBER...AND SURFACE TO 700MB THETA-E DIFFERENCE OF ONLY ABOUT 5
DEG K...VERY HEAVY RAINFALL IS EXPECTED. THUNDERSTORMS SHOULD BE
ABLE TO MAINTAIN EXTREMELY EFFICIENT RAINFALL RATES FOR AN
EXTENDED PERIOD OF TIME. RAINFALL AMOUNTS IN THE WATCH AREA SHOULD
AVERAGE 3 TO 5 INCHES WITH ISOLATED AMOUNTS IN EXCESS OF 7 INCHES.
ALL OF THIS ACTIVITY SHOULD MOVE EAST DURING THE MORNING HOURS
THURSDAY WITH MUCH DRIER AIR MOVING IN. WINDS WILL DIMINISH DURING
THE DAY AND TRICK OR TREATING WEATHER SHOULD BE QUITE NICE. THE
MAIN UPPER TROUGH WILL MOVE EAST AND A LARGE SURFACE HIGH WILL
BUILD IN FOR THE WEEKEND. THIS SHOULD BE SHORT LIVED AS ANOTHER
STRONG SYSTEM MOVES INTO THE WESTERN US EARLY NEXT WEEK. MOISTURE
WILL BE QUICK TO RETURN WITH RAIN CHANCES FOR MONDAY AND TUESDAY.
DUNN
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 66 79 53 77 50 / 80 20 5 0 0
WACO, TX 68 79 47 77 47 / 90 20 5 0 0
PARIS, TX 63 78 50 74 46 / 100 20 5 0 0
DENTON, TX 65 75 50 74 43 / 80 10 5 0 0
MCKINNEY, TX 64 76 50 76 46 / 100 20 5 0 0
DALLAS, TX 66 79 54 78 52 / 90 20 5 0 0
TERRELL, TX 64 78 50 76 47 / 100 20 5 0 0
CORSICANA, TX 64 80 52 75 50 / 100 30 5 0 0
TEMPLE, TX 69 79 48 78 49 / 100 30 5 0 0
MINERAL WELLS, TX 67 75 44 76 45 / 60 10 5 0 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 10 AM CDT THURSDAY FOR TXZ122-123-135-
146>148-158-160>162-174-175.
&&
$$
30/92
AREA FORECAST DISCUSSION
NWS ALBANY NY
1009 AM EDT THU OCT 31 2013
.SYNOPSIS...
A SIGNIFICANT STORM SYSTEM WILL IMPACT THE REGION THURSDAY INTO
FRIDAY...AS A STRONG AREA OF LOW PRESSURE TRACKS ACROSS THE WEST
CENTRAL GREAT LAKES AND SOUTHEAST CANADA...BRINGING WIDESPREAD
SHOWERS AND GUSTY WINDS TO OUR AREA FROM LATE TODAY INTO FRIDAY.
COOLER AIR WILL FILTER INTO THE REGION IN THE WAKE OF THE STORM
SYSTEM FOR THIS WEEKEND...WITH SOME SHOWERS POSSIBLE.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1000 AM EDT...CLOUDS HAVE ENCOMPASSED THE ENTIRE REGION WITH
FOG/MIST CONDITIONS CONTINUING. THE LEADING EDGE OF THE RAIN WAS
ACROSS CENTRAL NY AND EXTRAPOLATION OF THIS RAIN WILL REACH INTO
THE HUDSON RIVER VALLEY REGION AROUND NOON LOCAL TIME. THERE IS
SOME BREAKS IN THE PRECIP FIELD OVER SOUTHWEST NY STATE WHICH PER
THE HRRR COULD FILL IN LATER THIS AFTERNOON. SO LITTLE CHANGES TO
THE FORECAST WITH A GRADUAL INCREASE IN POPS FROM WEST TO EAST. AS
FOR WIND HEADLINES...NO CHANGES AT THIS TIME AS WE AWAIT FOR THE
12Z GUIDANCE BEFORE MAKING ANY ADJUSTMENTS.
AS OF 645 AM EDT...MID LEVEL CLOUDS CONTINUE TO INCREASE FROM THE
WEST...WHILE LOW LEVEL STRATUS CLOUDS HAVE CREPT NORTHWARD THROUGH
MUCH OF THE EASTERN HALF OF THE AREA. CLOUDS WILL CONTINUE TO
THICKEN THROUGH THE MORNING...AHEAD OF A WARM FRONT APPROACHING
FROM THE OHIO VALLEY. THE THREAT FOR SHOWERS WILL ALSO GRADUALLY
INCREASE TODAY...AS ISENTROPIC LIFT ON THE 295K SURFACE INCREASES.
WILL MENTION LIKELY POPS WEST OF THE CAPITAL REGION BY NOON...WITH
LIKELY OR CATEGORICAL POPS ACROSS MUCH OF THE AREA BY MID TO LATE
AFTERNOON. WILL MENTION THE HIGHEST POPS NORTH OF THE THE CAPITAL
REGION...WHERE A SOUTHERLY UPSLOPE COMPONENT WILL AID IN LOW LEVEL
ASCENT.
TEMPERATURES STARTING OUT COOL EARLY THIS MORNING MAINLY IN THE
UPPER 20S TO MID 30S...BUT SHOULD WARM STEADILY THROUGHOUT THE DAY
IN RESPONSE TO WARM ADVECTION AND AN INCREASING SOUTHERLY FLOW. IT
APPEARS SHOWERS WILL STILL BE LIKELY LATE THIS AFTERNOON AND EARLY
THIS EVENING...BUT IT WILL AT LEAST BE MILD FOR THIS TIME OF YEAR
WITH TEMPERATURES IN THE MID 50S TO LOWER 60S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
HIGH WIND WARNING HAS BEEN ISSUED FOR PORTIONS OF THE
WESTERN/SOUTHERN ADIRONDACKS AND WESTERN MOHAWK VALLEY LATE TONIGHT
THROUGH MUCH OF FRIDAY
TONIGHT INTO FRIDAY WE WILL BE DEALING WITH A POWERFUL STORM
SYSTEM...THAT WILL BE DEVELOPING TODAY OVER THE UPPER MIDWEST AND
EXPLOSIVELY STRENGTHEN OVER THE CENTRAL GREAT LAKES TONIGHT BEFORE
TRACKING NORTHEASTWARD THROUGH SOUTHERN QUEBEC ON FRIDAY. MODEL
GUIDANCE IN GENERALLY GOOD AGREEMENT WITH THE TRACK AND INTENSITY OF
THE SURFACE CYCLONE...WHICH DEPICTS A 970-975 MB LOW BY FRIDAY.
MODELS HAVE TRENDED SLIGHTLY FARTHER SOUTH AND EAST WITH THE TRACK
OF THIS SYSTEM...SO THIS HAS PROMPTED UPGRADING THE HIGH WIND WATCH
TO A HIGH WIND WARNING FOR HERKIMER...HAMILTON AND NORTHERN FULTON
COUNTIES. A SECONDARY LOW LEVEL JET CORE IS FORECAST TO MOVE ACROSS
LAKE ONTARIO AND THE ST. LAWRENCE VALLEY FRIDAY MORNING/AFTERNOON IN
WAKE OF THE PASSAGE OF AN OCCLUDED FRONTAL BOUNDARY...WITH DEEP
MIXING COMMENCING. THUS THE CONFIDENCE IN THE POTENTIAL FOR DAMAGING
WINDS HAS INCREASED ENOUGH SO THAT THE HIGH WIND WARNING HAS BEEN
ISSUED.
OTHERWISE...WINDS WILL GRADUALLY INCREASE ACROSS THE REGION TONIGHT
IN A SOUTH-SOUTHWEST FLOW REGIME. THE STRONGEST WINDS WILL BE OVER
HIGHER ELEVATIONS...AS IT APPEARS MIXING WILL BE LIMITED WITH
RELATIVELY STABLE LOW LEVELS DESPITE A 60-70 KT 850 MB JET MOVING
OVERHEAD LATE. CHANCES FOR RAIN WILL INCREASE ENOUGH TO MENTION
CATEGORICAL POPS MOST OF THE NIGHT...AS LARGE SCALE ASCENT INCREASES
AHEAD OF A POTENT UPPER LEVEL TROUGH/VORTICITY MAXIMUM. AT THE
SURFACE OUR REGION WILL BE IN A WARM SECTOR...WITH TEMPERATURES
GRADUALLY WARMING THROUGH THE OVERNIGHT HOURS AND ESPECIALLY BY
FRIDAY MORNING. BY SUNRISE MOST AREAS SHOULD WARM INTO THE UPPER
50S TO MID 60S.
THE POTENTIAL FOR STRONGEST WINDS WILL BE ON FRIDAY IN MULTIPLE
PHASES. FIRST...AN OCCLUDED FRONT TRAILING FROM THE PARENT LOW IN
QUEBEC WILL BE CROSSING THE AREA FROM WEST TO EAST FRIDAY MORNING.
WITH A SURGE IN LOW LEVEL TEMPERATURES AND DEWPOINTS...AND STRONG
LARGE SCALE ASCENT...IT IS POSSIBLE FOR ONE OR MULTIPLE LOW-TOPPED
LINES OF SHOWERS TO MIX DOWN THE STRONG WINDS ALOFT. THE COVERAGE OF
ANY LIGHTNING-PRODUCING CONVECTION IS LOW AT THIS TIME...SO NO
MENTION OF THUNDER IN THE FORECAST AS THE GREATER HAZARD WOULD BE
ANY STRONG WINDS THAT ARE ABLE TO MIX DOWN. THE SECOND PHASE OF
POSSIBLE STRONG WINDS WILL BE IN WAKE OF THE FRONTAL
PASSAGE...MOMENTUM TRANSFER INCREASES DUE TO DEEPER MIXING AS WINDS
SHIFT TO THE SOUTHWEST. THE STRONGEST CORE OF WINDS ALOFT WILL BE
MAINLY EAST OF THE ARE BY THEN /EXCEPT FOR NORTHWEST AREAS MENTIONED
PREVIOUSLY WHERE THE WARNING IS IN EFFECT/...HOWEVER WIND GUSTS MAY
BECOME STRONG ENOUGH TO REACH ADVISORY OR BORDERLINE WARNING LEVELS.
WILL CONTINUE TO MENTION THIS THREAT IN THE HWO.
TEMPERATURES SHOULD SPIKE IN THE FEW HOURS FOLLOWING THE OCCLUDED
FRONT PASSAGE...AS DEEPER MIXING WILL LEAD TO WARM SURFACE
TEMPERATURES AIDED FURTHER IN THE HUDSON VALLEY BY A SOUTHWEST
DOWNSLOPE COMPONENT. STILL THINKING UPPER 60S TO LOWER 70S A GOOD
BET FROM THE CAPITAL DISTRICT/HUDSON VALLEY SOUTH AND EAST...WITH A
FEW MID 70S EVEN POSSIBLE IN THE MID HUDSON VALLEY. SHOWERS WILL
TAPER OFF AS WELL...WITH GOOD DRYING TAKING PLACE DURING THE
AFTERNOON.
WIND SPEEDS WILL DECREASE AFTER DARK FRIDAY NIGHT...AS THE STORM
SYSTEM PULLS AWAY INTO THE CANADIAN MARITIMES. IT WILL STILL BE
GUSTY...ALTHOUGH THE THREAT FOR DAMAGING WINDS WILL HAVE ENDED. A
FEW LAKE ENHANCED SHOWERS WILL BE POSSIBLE OVER THE WESTERN
ADIRONDACKS...OTHERWISE IT WILL BE A DRY AND COOLER NIGHT FOR MUCH
OF THE AREA. A LARGER SCALE UPPER TROUGH WILL BE APPROACHING OUR
AREA FROM THE GREAT LAKES AND OHIO VALLEY ON SATURDAY...BRINGING
INCREASING CHANCES FOR SHOWERS DURING THE AFTERNOON. THE BEST CHANCE
WILL BE GENERALLY NORTH AND WEST OF THE CAPITAL REGION BY LATE IN
THE DAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THE MODEL GUIDANCE REMAINS IN FAIRLY GOOD AGREEMENT ON THE LONGWAVE
PATTERN. TROUGH MOVES EASTWARD ACROSS THE EASTERN UNITED STATES OVER
THE WEEKEND AS SHORT WAVE ENERGY ROTATES THROUGH IT. HEIGHTS RISE AS
WE HEAD INTO NEXT WEEK WITH RIDGING BUILDING IN OVER THE EASTERN
UNITED STATES WITH AN ANCHORING HIGH SETTING UP NEAR FLORIDA AS A
TROUGH DIGS OVER THE PLAINS.
AT THE SURFACE...A WAVE OF LOW PRESSURE IS EXPECTED TO FORM ALONG A
COLD FRONTAL BOUNDARY MOVING OFF THE EAST IN RESPONSE TO A SHORT
WAVE ROTATING THROUGH THE BASE OF THE TROUGH...WHILE A SECONDARY
COLD FRONT MOVES ACROSS THE REGION. WITH THE PASSAGE OF THIS
SECONDARY BOUNDARY A MUCH COLDER AIRMASS WILL BE USHERED IN.
CANADIAN HIGH PRESSURE THEN BUILDS IN FROM THE WEST AND IS EXPECTED
TO CREST OVER THE REGION MONDAY...THEN SHIFT OFF THE NEW ENGLAND
COAST TUESDAY.
SOME RAIN AND SNOW SHOWERS WILL LINGER THROUGH SATURDAY NIGHT AS THE
UPPER TROUGH SWINGS THROUGH ALONG WITH SOME LAKE ENHANCEMENT. WITH
HEIGHTS BEGINNING TO RISE ON SUNDAY AND HIGH PRESSURE BUILDING IN AT
THE SURFACE CLOUD COVER WILL DECREASE. DESPITE INCREASING SUNSHINE
IT WILL BE CHILLY AS BRISK AND GUSTY NORTHWESTERLY WINDS...COLD AIR
ADVECTION...BRING IN A COLDER AIRMASS. HIGHS SUNDAY WILL BE AROUND
10 DEGREES BELOW NORMAL...GENERALLY RANGING FROM THE MID 30S TO
UPPER 40S.
SUNDAY NIGHT SHOULD BE THE COLDEST NIGHT OF THE SEASON WITH CLEAR
SKIES AND DIMINISHING NORTHERLY WINDS. TEMPERATURES ACROSS THE
FORECAST AREA ARE EXPECTED TO DROP INTO THE 20S WITH TEENS
ACROSS PORTIONS OF THE WESTERN ADIRONDACKS. THE LAST TIME WE HAD
WIDESPREAD TEMPERATURES THIS COLD WAS BACK IN EARLY APRIL.
IT WILL BE CHILLY ON MONDAY WITH THE HIGH CRESTING OVER THE
REGION...THEN TEMPERATURES WILL MODERATE AS THE HIGH SHIFTS OFFSHORE
AND RETURN FLOW SETS UP. SEASONABLE READING ARE ANTICIPATE TUESDAY
WITH A BIT ABOVE NORMAL ON WEDNESDAY.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
A STRONG STORM SYSTEM WILL IMPACT THE REGION TODAY AND FRIDAY. THE
LOW WILL PASS WELL TO OUR NORTH AND WEST ACROSS THE GREAT LAKES
REGION AND INTO EASTERN CANADA. THE SYSTEM WARM FRONT WILL LIFT
NORTHEAST AND CROSS THE REGION TODAY FOLLOWED BY THE SYSTEM`S COLD
FRONT ON FRIDAY. STRONG WINDS WILL ACCOMPANY THIS SYSTEM.
HIGH LEVEL CLOUDS OVERSPREAD THE REGION...HOWEVER RADIATIONAL
FOG AND STRATUS DEVELOPED BEFORE THE HIGHER CLOUDS CAME IN. IN
ADDITION...STRATUS HAS SPREAD NORTH UP THE HUDSON VALLEY. CLOUDS
SHOULD LIFT SOME AFTER THE WARM FRONT PASSES BUT ONLY TO MVFR. IFR
WILL RETURN BY LATE AFTERNOON THEN PERSIST THROUGH THE OVERNIGHT IN
THE RAIN AHEAD OF THE APPROACHING COLD FRONT.
THE LOW LEVEL JETS ASSOCIATED WITH THIS SYSTEM WILL BE STRONG
RESULTING IN LOW LEVEL WIND SHEAR AT KPOU...KPSF AND KGFL DEVELOP
THIS AFTERNOON AND CONTINUING INTO THE OVERNIGHT AS SURFACE WINDS
REMAIN LIGHT AT LESS THAN 10 KNOTS. WHILE AT KALB...SURFACE WINDS
ARE EXPECTED TO INCREASE WITH SOME MIXING SO LLWS NOT MENTIONED IN
TAF BUT NEEDS TO BE CLOSELY MONITORED.
OUTLOOK...
FRI NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SAT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
SAT NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
SUN: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
SUN NIGHT-TUE: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
A SIGNIFICANT STORM SYSTEM WILL IMPACT THE REGION THURSDAY INTO
FRIDAY...AS A STRONG AREA OF LOW PRESSURE TRACKS ACROSS THE WEST
CENTRAL GREAT LAKES AND SOUTHEAST CANADA...BRINGING WIDESPREAD
SHOWERS AND GUSTY WINDS TO OUR AREA FROM LATE TODAY INTO FRIDAY.
COOLER AIR WILL FILTER INTO THE REGION IN THE WAKE OF THE STORM
SYSTEM FOR THIS WEEKEND...WITH SOME SHOWERS POSSIBLE.
MINIMUM RELATIVE HUMIDITY VALUES WILL ONLY BE BETWEEN 65 AND 80
PERCENT TODAY...INCREASING TO AROUND 85 TO 100 PERCENT TONIGHT. RH
VALUES WILL DROP TO BETWEEN 50 AND 65 PERCENT ON FRIDAY.
WINDS TODAY WILL BECOME SOUTHERLY AROUND 10 TO 15 MPH. WINDS TONIGHT
WILL REMAIN SOUTH...WITH SPEEDS INCREASING TO 15 TO 25 MPH WITH
GUSTS TO 35 MPH POSSIBLE. WINDS ON FRIDAY WILL SHIFT TO THE
SOUTHWEST AND INCREASE FURTHER TO AROUND 20 TO 35 MPH...WITH GUSTS
OF 45 TO 60 MPH POSSIBLE.
&&
.HYDROLOGY...
NO HYDRO ISSUES ARE ANTICIPATED THROUGH THE PERIOD. OVERALL RIVER
AND STREAM LEVELS ARE NEAR TO SLIGHTLY BELOW NORMAL FOR LATE
OCTOBER.
A STRONG SYSTEM LOOKS TO IMPACT THE REGION TODAY INTO FRIDAY WITH
WIDESPREAD RAINFALL. DUE TO THE EXPECTED PROGRESSIVE NATURE OF THIS
SYSTEM AND RECENT DRY ANTECEDENT CONDITIONS...RAINFALL SHOULD NOT BE
HEAVY ENOUGH TO CAUSE HYDRO PROBLEMS. QPF AMOUNTS ARE EXPECTED TO
RANGE FROM HALF AN INCH TO AN INCH AND A HALF...WITH ISOLATED
AMOUNTS NEAR TWO INCHES. THIS WILL LIKELY CAUSE SOME WITHIN BANK
RISES ON MAIN STEM RIVERS.
OVER THE WEEKEND...MAINLY SCATTERED SHOWERS ARE FORECAST WITH LIGHT
PRECIPITATION AMOUNTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...HIGH WIND WARNING FROM 2 AM TO 6 PM EDT FRIDAY FOR NYZ032-033-
038-082.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...KL/JPV
NEAR TERM...BGM/JPV
SHORT TERM...JPV
LONG TERM...IAA
AVIATION...IAA
FIRE WEATHER...JPV
HYDROLOGY...KL/JPV
FOR THE LATEST UPDATES...PLEASE VISIT OUR WEBPAGE AT
WWW.WEATHER.GOV/ALBANY
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
1013 AM EDT Thu Oct 31 2013
.NEAR TERM [Through Today]...
Just made a few tweaks to the PoP grid this morning. Otherwise
current forecast remains on track. A surface cold front, currently
passing through Missouri, will continue to move southeastward
throughout the day. Ahead of the front there is an ample moisture
feed off the Gulf signified on our 12Z TAE sounding that shows
significant moisture to about 800mb. Despite the ample moisture
present, all instability and forcing dynamics are located further
west closer to the front and associated upper level low. Therefore
besides maybe a weak shower in our far western CWA, not expecting
rain today. This is confirmed with latest runs of the HRRR and our
local 4KM WRF. Otherwise for the remainder of today expect cloud
cover to increase from west to east, high temperatures in the low
to mid 80s, and winds out of the south around 15-20 mph.
&&
.SHORT TERM [Tonight Through Saturday]...
Upper ridge across the southeastern states will break down tonight
as a potent trough exits the central states. Surface ridge over
the mid-Atlantic states will retreat east as well, allowing for
increasing southerly flow across the forecast area. Narrow band of
deep layer moisture, ahead of the cold front, will push into SE
Alabama late tonight with a band of showers and isolated
thunderstorms. This band of showers and storms will push across
the remainder of the forecast area during the day on Friday before
exiting the southeastern zones early Saturday morning.
Temperatures on Friday will vary from northwest to southeast on
Friday in association with the front. Expect to see mid to upper
70s for the northwest and mid 80s over the southeast.
Models continue to show the bulk of the upper forcing and support
lifting well to the northeast of the area tonight and Friday as
the primary shortwave shears out. This will significantly limit
height falls across the region, keeping instability in check.
However, the presence of strong low- to mid-level flow (40kt deep
layer shear) may support an isolated strong to severe thunderstorm
or two, especially during the day on Friday. Overall, the severe
threat is rather small, with the SPC Day 2 outlook indicating 5
percent probs.
A cooler and drier airmass will push into the region on Saturday,
with highs in the mid to upper 70s anticipated.
&&
.LONG TERM [Saturday Night through Wednesday]...
Overnight lows will be in the mid to upper 40s Saturday and
Sunday nights with highs on Sunday mainly in the upper 60s, with
some lower 70s in the FL Big Bend. Temps will moderate early next
week as the low level flow becomes more easterly. These winds will
also increase moisture levels with low-end rain chances returning
for Tuesday and Wednesday. The next frontal system looks like it
will hold off until later next week.
&&
.AVIATION...
[Through 12z Friday] Skies will be dominated by high clouds at
KTLH, KABY, and KVLD, while VFR low/mid clouds will be likely at
KDHN and KECP. Scattered showers will also be a possibility later
today at KDHN and KECP. Expect gusty south winds this afternoon at
all terminals, predominantly in the 20 to 25 knot range, with
isolated gusts up to 30 knots.
&&
.MARINE...
Strong onshore flow ahead of an approaching cold front will keep
exercise caution conditions in place over the waters into tonight.
Winds may reach advisory levels on Friday as the front pushes
across the waters. Offshore flow will develop on Saturday in the
wake of the front and increase to advisory levels Saturday night.
Strong high pressure north of the waters will then headline
conditions in place through early next week.
&&
.FIRE WEATHER...
Relative humidity values will remain above critical levels for
the foreseeable future, precluding any Red Flag conditions.
However, it should be mentioned that transport winds will be quite
high this afternoon, resulting in high dispersion indices.
&&
.HYDROLOGY...
A cold front will pass slowly through the region Friday through
Saturday morning. Average rainfall totals of just over an inch can
be expected across the northwestern portions of the forecast area
trending down to three quarters of an inch south and east of
Tallahassee. This will have little to no impact on area rivers and
streams as flows remain well below action stage at this time.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 83 66 83 58 77 / 10 10 50 70 20
Panama City 81 72 79 61 75 / 30 20 70 60 10
Dothan 83 68 79 52 75 / 30 30 80 40 10
Albany 83 68 79 54 74 / 10 20 70 60 10
Valdosta 84 64 82 60 76 / 10 10 40 70 30
Cross City 85 64 83 66 77 / 10 10 30 60 50
Apalachicola 80 72 80 63 76 / 20 20 50 70 30
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
Near Term...Navarro/DVD
Short Term/Marine...Camp
Long Term...Wool
Aviation/Fire Wx...Harrigan
Hydrology...Lamers
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1103 AM CDT THU OCT 31 2013
.DISCUSSION...
402 AM CDT
MAIN FORECAST CONCERNS THIS MORNING ARE FOCUSED ON ADDITIONAL HEAVY
RAINFALL AMOUNTS ACROSS THE CENTRAL/SOUTHERN PARTS OF THE CWA...AND
SOME POTENTIAL FOR A FEW STRONG/SEVERE THUNDERSTORMS THIS AFTERNOON
ACROSS THE SOUTHEAST.
SURFACE LOW PRESSURE WAS DEEPENING OVER THE UPPER MISSISSIPPI VALLEY
EARLY THIS MORNING...IN RESPONSE TO STRONG FORCING ASSOCIATED WITH
UPPER TROUGH PROPAGATING ACROSS THE CENTRAL CONUS. WITH DEEPENING
AND NORTHWARD MOVEMENT OF THE SURFACE LOW...WARM FRONT HAS DEVELOPED
NORTH ACROSS THE AREA OVERNIGHT WITH A VERY MILD/MOIST AIR MASS
SPREADING ACROSS THE FORECAST AREA. SEVERAL SMALLER MID-LEVEL SHORT
WAVES EMERGING AHEAD OF THE LARGER SCALE UPPER TROUGH IN SOUTHWEST
FLOW HAVE PRODUCED PERIODS OF MODERATE/LOCALLY HEAVY RAINFALL SINCE
LAST EVENING...WITH A COUPLE OF SWATHS OF 2+ INCH RAINFALL AMOUNTS
OVER THE SOUTHERN HALF OF THE CWA. THE EXCEPTION HAS BEEN THE FAR
SOUTHEAST CORNER...WHICH WAS SOUTH OF THE HEAVIER RAIN AXIS
OVERNIGHT. ADDITIONAL RAINFALL IS ON THE WAY...AS CURRENT SHORT WAVE
AND THEN STRONGER UPSTREAM WAVE CURRENTLY LIFTING NORTHEAST FROM THE
TX/OK PANHANDLE REGION TRACK TOWARD THE AREA. THESE IN COMBINATION
WITH LARGE SCALE ASCENT AND HEIGHT FALLS WITH THE APPROACHING UPPER
TROUGH SHOULD CONTINUE TO GENERATE CLUSTERS OF MODERATE/LOCALLY
HEAVY RAIN THROUGH THE DAY. MOST OF THE HIGH-RES CONVECTION ALLOWING
GUIDANCE...ARW/NMM/HRRR ETC...INDICATE THAT THE SOUTHEAST HALF OF
THE CWA WILL LIKELY SEE MORE FOCUSED RAINFALL AND EMBEDDED THUNDER
AFTER PERHAPS AN EARLY MORNING LULL. WITH THE UNSEASONABLY MOIST AIR
MASS AND STRONG/PERSISTENT FORCING...AM CONCERNED THAT AN ADDITIONAL
1-2 INCHES OF RAINFALL COULD CAUSE SOME LOCALIZED FLOODING AND RISES
ON SMALLER TRIBUTARIES AND CREEKS. HOWEVER...SINCE RAINFALL WILL BE
SPREAD OUT OVER 24 HOURS FOR THE MOST PART HAVE DECIDED TO HOLD OFF
ON A FLOOD WATCH. WILL HOWEVER ISSUE AN ESF/HYDROLOGIC OUTLOOK TO
ADDRESS RAINFALL AMOUNTS AND ANTICIPATED EFFECTS.
OTHER CONCERN IS FOR THE POSSIBILITY OF SOME STRONG/SEVERE
THUNDERSTORMS TO AFFECT SOUTHEAST PARTS OF THE CWA THIS AFTERNOON
AHEAD OF THE COLD FRONT. A STRONG MID-LEVEL JET STREAK IS EXPECTED
TO SPREAD ACROSS THE REGION THIS AFTERNOON WITH THE APPROACH OF THE
STRONGER SHORT WAVE NOW OVER THE PLAINS. COUPLED WITH 50 KT LOW
LEVEL JET STREAK AROUND 850 MB...0-6 KM BULK SHEAR WILL INCREASE TO
70-80 KT BY LATE AFTERNOON COINCIDENT WITH THE ADVANCING COLD FRONT.
WHILE SFC-BASED INSTABILITY MAY BE LACKING DUE TO MOIST FLOW/CLOUDS
THERE APPEARS TO BE SUFFICIENT WEAK ELEVATED CAPE MAINLY ACROSS OUR
SOUTHEAST COUNTIES TO SUPPORT SOME ORGANIZED THUNDERSTORMS AHEAD OF
THE FRONT. DAMAGING WIND GUSTS WOULD BE THE MOST LIKELY SEVERE
THREAT WITH QUICK MOVING STORMS AND PLENTY OF MOMENTUM JUST ABOVE
THE BOUNDARY LAYER...THOUGH A CONDITIONAL LOW PROBABILITY TORNADO
THREAT EXISTS AS WELL WITH 0-1 KM BULK SHEAR NEAR 40 KT AND MOIST
LOW LEVELS. SPC HAS OUTLOOKED OUR SOUTHEAST COUNTIES FOR A SLGT RISK
OF SEVERE THIS AFTERNOON. THE COLD FRONT WILL PUSH EAST OF THE AREA
BY EARLY THIS EVENING... THOUGH SCATTERED SHOWERS MAY LINGER BEHIND
THE FRONT FOR A TIME AS STRONG UPPER TROUGH AXIS LAGS THE SURFACE
BOUNDARY. PRECIP SHOULD END FROM WEST TO EAST...ENDING BY OR SHORTLY
AFTER MIDNIGHT IN NORTHWEST INDIANA.
COOLER WEATHER THEN RETURNS LATER TONIGHT AND FRIDAY...WITH ANOTHER
STRONGER SHORT WAVE DIGGING ACROSS THE AREA FRIDAY NIGHT/EARLY
SATURDAY TO BRING A REINFORCING PUSH OF COLDER AIR FOR THE WEEKEND.
INSTABILITY STRATOCU AND A FEW SHOWERS/SPRINKLES ARE POSSIBLE WITH
THIS STRONGER WAVE FRIDAY NIGHT/SATURDAY...BEFORE HIGH PRESSURE
BUILDS IN FROM THE WEST SATURDAY NIGHT. AFTER 60S TODAY...EXPECT
HIGHS IN THE UPPER 40S/LOWER 50S FOR THE WEEKEND. LOWS SUNDAY
MORNING WILL LIKELY DIP INTO THE 20S WEST OF CHICAGO...WHERE
CLEARING SKIES AND THE SURFACE RIDGE AXIS WILL SUPPORT STRONG
RADIATIONAL COOLING. ANOTHER LOW PRESSURE SYSTEM IS PROGGED TO LIFT
ACROSS THE UPPER MIDWEST EARLY NEXT WEEK...BRINGING SOUTH WINDS AND
MILDER TEMPS AT LEAST WELL INTO THE 50S. THE CHANCE OF RAIN WILL
INCREASE AGAIN MONDAY NIGHT THROUGH MID-WEEK AS GUIDANCE CURRENTLY
INDICATES ANOTHER SURFACE WAVE RIPPLING UP THE APPROACHING COLD
FRONT.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* PERIODS OF IFR CIGS THROUGH THE DAY.
* PERSISTENT RAIN RETURNING THIS AFTERNOON...WITH LOWER VIS IN THE
HEAVIER RAIN.
* ISOL/SCT THUNDERSTORMS STILL POSSIBLE THIS AFTERNOON...MAINLY
SOUTH OF THE TERMINALS.
* PERIOD OF VERY GUSTY WESTERLY WINDS BY EARLY THIS EVENING IN THE
WAKE OF THE COLD FRONT.
RODRIGUEZ/KB
//DISCUSSION...UPDATED 12Z...
LOWER CEILINGS REMAINING SITUATED ACROSS THE REGION THIS MORNING
WITH TERMINALS REPORTING LOW END MVFR OR IFR AT THIS HOUR. ANY LOW
END MVFR IN PLACE AT THIS HOUR WILL BE REPLACED WITH IFR CEILINGS
OVER THE NEXT 1-2 HOURS...AND EXPECT THESE CEILINGS TO REMAIN IN
PLACE WITH LITTLE OR NO IMPROVEMENT THROUGH THE DAY. HAVE REMOVED
THE LIFR CEILINGS IN THE TAF WITH ANY OF THESE CONDITIONS ONLY
BEING OBSERVED UNDER TROUGH AXIS OVER EASTERN IOWA. THIS TROUGH
AXIS WILL SHIFT EAST THROUGH THIS MORNING AND THINK THAT BY THE
TIME THIS MOVES OVERHEAD...SOME SLIGHT IMPROVEMENT INTO THE IFR
RANGE WILL HAVE OCCURRED. ITS NOT UNTIL FROPA LATE THIS AFTERNOON
AND EARLY EVENING THAT ANY IMPROVEMENT IS EXPECTED...WITH MVFR
CONDITIONS BECOMING MORE LIKELY. AREA OF RAIN WILL CONTINUE
EXITING NORTHEAST ILLINOIS AND NORTHWEST INDIANA OVER THE NEXT
COUPLE OF HOURS WITH A BRIEF LULL IN THE ACTIVITY EXPECTED BEFORE
UPSTREAM RAIN MOVES BACK OVERHEAD BY MID DAY. CONTINUED RAIN IS
EXPECTED OUT AHEAD OF FRONT THIS AFTERNOON AND ITS DURING THIS
TIME FRAME THAT ISOL/SCT THUNDERSTORMS COULD MOVE ACROSS THE
TERMINALS. ALTHOUGH DUE TO LOW CONFIDENCE...HAVE LEFT OUT ANY
MENTION OF THUNDERSTORMS AT THIS TIME. SOUTH TO SOUTHWEST WINDS
WILL BE OBSERVED FORM MOST OF TODAY BEFORE SHIFTING MORE SOUTHWEST
AND THEN WEST WITH FROPA...WITH WINDS ALSO BECOMING GUSTY BEHIND
THE FRONT.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM TO HIGH CONFIDENCE WITH CEILINGS/TRENDS.
* HIGH CONFIDENCE WITH RAIN TODAY.
* LOW CONFIDENCE WITH THUNDERSTORMS AT THE TERMINALS.
* MEDIUM CONFIDENCE WITH GUSTY WINDS THIS EVENING.
RODRIGUEZ/KB
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...CHANCE OF SHOWERS...OTHERWISE VFR.
SATURDAY...SLIGHT CHANCE OF SHOWERS...OTHERWISE VFR.
SUNDAY...VFR.
MONDAY...CHANCE OF SHOWERS LATE...OTHERWISE VFR.
TUESDAY...CHANCE OF SHOWERS...OTHERWISE VFR.
WEDNESDAY...CHANCE OF SHOWERS...OTHERWISE VFR.
RODRIGUEZ
&&
.MARINE...
702 AM CDT
STRONGER WINDS EXPECTED OVER THE LAKE AND THE NEARSHORE WATERS
TONIGHT...WITH GALES LIKELY ACROSS THE ENTIRE LAKE AND THE INDIANA
NEARSHORE WATERS.
A TROUGH OF LOW PRESSURE OVER THE UPPER MIDWEST WILL CONTINUE
LIFTING TO THE NORTHEAST ACROSS THE CENTRAL GREAT LAKES REGION
TODAY WHILE DEEPENING....WITH SOUTHERLY WINDS LIKELY ACROSS THE
LAKE. ALTHOUGH AS THIS LOW CONTINUES NORTHEAST INTO SOUTHEAST
ONTARIO AND SOUTHERN QUEBEC TONIGHT INTO EARLY FRIDAY...IT WILL
FURTHER DEEPEN WITH A PERIOD OF STRONGER WINDS DEVELOPING ACROSS
THE ENTIRE LAKE. EXPECT GALES TO 35 KT TO DEVELOP OVER THE
NORTHERN PORTIONS...AND THEN TO 40 KT OVER THE SOUTHERN HALF
TONIGHT BEFORE DIMINISHING ONCE AGAIN EARLY FRIDAY MORNING. WINDS
WILL REMAIN SOMEWHAT STRONGER INTO SATURDAY AS A TROUGH OF LOW
PRESSURE WILL LINGER ACROSS THE EASTERN GREAT LAKES. THIS TROUGH
WILL SHIFT EAST SATURDAY NIGHT...WHILE HIGH PRESSURE BUILDS EAST
ACROSS THE CENTRAL PLAINS AND THEN INTO THE WESTERN GREAT LAKES.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 9 PM THURSDAY.
GALE WARNING...LMZ743-LMZ744-LMZ745...9 PM THURSDAY TO 4 AM
FRIDAY.
GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...9 PM THURSDAY TO 9 AM
FRIDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...4 PM THURSDAY TO
10 AM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
[top]
Area Forecast Discussion
National Weather Service Lincoln IL
1028 AM CDT Thu Oct 31 2013
.DISCUSSION...
ISSUED 1027 AM CDT Thu Oct 31 2013
Widespread showers continuing over all of the CWA this morning,
although a narrow dry slot in the St Louis area is trying to move
in. Latest surface observations show the cold front along the
Illinois/Iowa border extending southwest into southeast Kansas.
Latest HRRR shows the front near the I-57 corridor by 00Z, with a
narrow line of convection firing along it early this afternoon.
Southeast half of the forecast area remains in the slight risk for
severe weather this afternoon, but areas along/east of I-57 may
see the best shot of any damaging winds. Temperatures across the
northwest CWA will be falling later this afternoon behind the
front, but should still reach the mid to upper 60s in most areas
ahead of it.
Updated zones/grids have been sent. These mainly adjusted the
hourly temperature trends. Also did some tweaks to the rain trends
this evening behind the front.
Geelhart
&&
.AVIATION...
ISSUED 630 AM CDT Thu Oct 31 2013
Timing of cold front and TSRA across the forecast area along with
coverage of MVFR/IFR cigs the main forecast challenges this period.
Cold front was located over east central Iowa as of 11z...and will
slow push into our area by early this afternoon. Widespread MVFR
and local IFR cigs common across the area with a trend towards more
IFR cigs this morning as another wave of rain moves across the
forecast area. Cold front is expected to push across our western
areas between 18z-21z...and to the east of our TAF sites by around
00z. The better chances for any TSRA and brief reductions in cigs
and vsbys to LIFR will be right along the cold front. Once the
front clears our area this evening, look for winds, which will be
mainly out of a south direction at 12 to 17 kts this morning, to
veer more into a southwest to west direction with FROPA this
afternoon and evening. May see some gusts up to 25 kts today ahead
of the front, especially from DEC to CMI and then again just behind
the front late this afternoon into this evening as the colder air
works its way into our area.
Smith
&&
.PREV DISCUSSION...
ISSUED 237 AM CDT Thu Oct 31 2013
SHORT TERM...Today through Saturday
Periods of rain will persist across central Illinois today, as a
moist southwesterly flow continues ahead of a slowly approaching
cold front. Boundary will reach the I-55 corridor by around
midday, then will push into western Indiana by early evening. Main
question of the day will be if any severe weather will develop
ahead of the front this afternoon/evening. Forecast soundings
continue to show a saturated and rather stable warm sector:
however, latest run of the NAM suggests a weak surface wave riding
northeastward along the boundary may pull a slightly more unstable
airmass into east-central and southeast Illinois later today. This
added instability will combine with impressive 0-6km shear values
of 80 to 90kt to potentially produce a few strong to severe
storms. 4km WRF-NMM hints at a possible narrow squall line ahead of
the front between 2 PM and 8 PM, mainly along/east of I-57. As a
result, the Storm Prediction Center (SPC) has outlooked much of
east-central and southeast Illinois for a slight risk of severe.
Any storms that develop will push into Indiana after 8 PM:
however, scattered showers will persist further west through the
evening hours. Total rainfall today into this evening will
generally range from 1 to 1.50, but will be higher within stronger
storms.
Partly to mostly sunny skies and cooler conditions can be expected
on Friday in the wake of the departing cold front. High
temperatures will be several degrees cooler than today, ranging
from the middle 50s far north to the lower 60s south of I-70.
Clouds will be on the increase Friday afternoon/evening, as a
short-wave digs southeastward out of the Northern Plains. This
feature will carve a trough across the Great Lakes Friday night
into Saturday. Models continue to produce a few light showers
beneath this feature, mainly across northern Illinois into
north-central Indiana. As a result, will maintain a cool/dry
forecast across central Illinois through Saturday.
LONG TERM...Sunday through Wednesday
High pressure will provide continued cool/dry weather for Sunday
and Monday before the next system begins to approach from the west
by Tuesday. Significant model spread exists concerning speed of
system, mainly due to varying strengths of blocking upper ridge
progged to develop in the southeast U.S. ECMWF is indicating an
unseasonably strong 594dm 500mb high building over the Carolinas
early next week, which slows the eastward progression of an upper
wave and associated cold front across the central CONUS. This
solution would bring an extended period of rain chances to central
Illinois from Tuesday through Thursday. Meanwhile, both the GFS
and GEM are slightly weaker with the Carolinas high and thus bring
the Plains system eastward through the region a bit faster. Rain
chances with this solution would generally be confined to just
Tuesday and Wednesday. Whichever solution eventually pans out, it
appears another period of beneficial rainfall is likely early next
week. Have included PoPs for Tuesday and Wednesday, hitting rain
chances hardest across the entire area on Wednesday. After a
chilly weekend, temps will return to near normal in the upper
50s/lower 60s next week.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
642 AM CDT THU OCT 31 2013
.SHORT TERM /TODAY/...
ISSUED AT 335 AM CDT THU OCT 31 2013
LOW PRESSURE HAS MOVED INTO NERN IA NOW WITH THE COLD FRONT ALONG
THE EAST EDGE OF THE CWA. COLD FRONT WILL CONTINUE TO MAKE
PROGRESS...HOWEVER UPPER LOW NOT LIFTING THROUGH THE OK PANHANDLE
WILL RESULT IN AN EXPANSION OF THE RAIN WESTWARD AGAIN. HRRR HAD A
PRETTY GOOD HANDLE ON IT. ALTHOUGH THE FARTHEST WEST OF THE
MODELS...IT DOES NOT LOOK ALL THAT BAD GIVEN RADAR TRENDS.
EXPANSION HAS BEEN PUT INTO THE GRIDS FOR THIS MORNING WITH RAIN
GRADUALLY ENDING FROM THE WEST THIS AFTERNOON. TEMPS WILL NOT RISE
IN THE SOUTHEAST TODAY WITH MODEST RISES IN THE NORTHWEST. WINDS
WILL BECOME A SOMEWHAT GUSTY FOR A WHILE TODAY...BUT NOT MUCH HIGHER
THAN 20 MPH OR SO.
.LONG TERM /TONIGHT THROUGH WEDNESDAY/...
ISSUED AT 335 AM CDT THU OCT 31 2013
SYSTEM WILL DEPART TO THE EAST TONIGHT WITH SUBSIDENCE...CLEARING
AND COOLER TEMPERATURES. HOWEVER...ANOTHER SHORTWAVE WILL RAPIDLY
ADVANCE ON THE STATE FROM THE NORTHWEST ON FRIDAY. MOISTURE WILL
BE GENERALLY LACKING WITH THIS SYSTEM...HOWEVER DECENT MID LEVEL
FORCING AND STEEP LAPSE RATES WILL LEAD TO ISOLD/SCT SHOWER
DEVELOPMENT ACROSS NORTHERN IOWA BY AFTERNOON. FARTHER SOUTH...
SOUNDINGS ARE DRIER WITH LESS THREAT OF PCPN. WINDS WILL BE QUITE
STRONG ON FRIDAY AS WELL WITH DECENT PRESSURE GRADIENT AND NEARLY
UNIDIRECTIONAL FLOW THROUGH A GOOD DEPTH OF THE ATMOSPHERE...AND
HELPED ALONG WITH NEARLY ADIABATIC LAPSE RATES IN THE LOW LEVELS.
QUITE WEATHER IS EXPECTED THIS WEEKEND AS HIGH PRESSURE MOVES
ACROSS THE STATE. SOUTH WINDS WILL INCREASE QUICKLY ON SUNDAY ON
BACKSIDE OF HIGH AS LARGE WESTERN TROF DEVELOPS. GFS AND EURO
COMING CLOSER ON SOLUTIONS AND INDICATE A PROLONGED PERIOD OF
RAINFALL CHANCES FROM LATE SUNDAY NIGHT INTO WEDNESDAY. IOWA WILL
BE ON WESTERN EDGE OF WARM CONVEYOR BELT FROM GULF OF MEXICO WITH
DECENT RAINS EXPECTED...ESPECIALLY MOVING TO THE EAST ACROSS THE
STATE. TEMPERATURES MAY COOL ENOUGH BEHIND A SLOWLY MOVING COLD
FRONT FOR SOME TRANSITION TO SNOW BY TUESDAY NIGHT IN THE FAR
NORTHWEST.
&&
.AVIATION...31/12Z
ISSUED AT 639 AM CDT THU OCT 31 2013
WIDESPREAD IFR AND LIFR CONDITIONS THIS MORNING WILL IMPROVE
GRADUALLY DURING THE DAY AS DRIER AIR WORKS ITS WAY IN FROM THE
WEST. UPPER LEVEL DISTURBANCE OVER SWRN KS WILL RACE NORTHEAST AND
BRING AN AREA OF RAIN ACROSS THE SOUTHEAST HALF OF THE STATE. RAIN
WILL END WITH CLEARING SKIES ACROSS THE TAF SITES LATER THIS
AFTERNOON INTO THE EVENING.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...MS OCT 13
LONG TERM...COGIL
AVIATION...MS OCT 13
AREA FORECAST DISCUSSION
NWS TOPEKA KS
939 AM CDT Thu Oct 31 2013
.UPDATE...
Issued at 936 AM CDT THU OCT 31 2013
Ran an update to take out the flash flood watch as threat for
widespread heavy rainfall continues to diminish. Light to moderate
rain is expected to continue this morning generally along and
southeast of the turnpike, however clusters of showers and storms
are progressive with breaks between. Cooler drier air also
continues to move in through the low levels and heavier rainfall
shifting slowly southward. Debated bringing highs down a few
degrees, but think late day sunshine will bring highs back into
the 50s for much of the area albeit late in the day.
&&
.SHORT TERM...(Today and Tonight)
Issued at 358 AM CDT THU OCT 31 2013
Well finally the upper level trough is making progress east, and the
08z water vapor imagery shows the last and most impressive shortwave
lifting across the OK panhandle. Surface obs show the front has
moved into east central KS from Burlington to Eudora. Profiler data
suggests the 850MB front is a little further west near McPherson to
near Alma and into southwest IA.
Today will see an end to the wet and gloomy weather as the upper
level wave propagates east of the area. However this morning will be
wet across eastern KS. Most model guidance is showing decent mid
level frontogenesis along the 850 front with some moisture
lingering. Additionally there should be a decent shot of QG forcing
and PVA from the shortwave lifting out from the panhandles. So there
will be one last shot of widespread shower activity with some
embedded thunderstorms. Think that the rain will come to an end once
the 850 front and the associated frontogenesis pushes south and east
of the forecast area. This looks to occur by the early afternoon
with skies clearing out by the late afternoon hours. With recent
trends showing precip becoming more stratiform in nature, rainfall
rates may not be quite as high as yesterday, but with PWs still over
an inch across east central KS, there could still be around an inch
of additional rain accumulations. Therefore will maintain the flash
flood watch for areas along and southeast of the turnpike, although
the threat does not appear to be widespread. Areas further northwest
have not received as much rain and so will cancel the watch early
for these area.
Highs today will be tricky depending on when the clouds clear out.
Think north central KS will warm into the lower 60s while parts of
northeast and east central KS could stay in the middle 50s due to
cloud cover. Lows tonight are forecast to fall into the 30s and have
not made any big changes from the previous forecast. Models show dry
air advecting in from the west with dewpoint falling into the lower
30s. Clear skies should help with some radiational cooling. Winds
are forecast to remain from the west at 5 to 10 MPH overnight. Think
this along with the dry air advection are expected to mitigate any
widespread fog formation tonight. If it looks like winds will
decouple, later shifts may need to readdress this.
Wolters
.LONG TERM...(Friday through Wednesday)
Issued at 358 AM CDT THU OCT 31 2013
Next shortwave trough to move through in northwest flow aloft on
Friday will pass primarily north and east of the county warning area
so will keep mostly sunny skies with highs from the upper 50s
northern counties to the lower 60s south. Strong mixing will result
in gusty northwest winds of 15 to 25 mph but will gradually decrease
late in the afternoon. Although skies will be clear with decreasing
winds Friday night with saturated soils...will not insert fog into
forecast at this point as so mixing still evident with the high center
to the south and west of the CWA.
Will continue with a dry weekend forecast. Surface to start the day
Saturday will result in light winds and less mixing so will keep
cooler highs in the 50s before warming back into the low to middle
60s for Sunday as gusty south winds return ahead of deepening
leeside surface trough. Next chance for showers appears with the
developing llvl jet and resulting warm air advection Sunday night.
As the western trough advanced into the plains Monday night and
Tuesday and interacts with a surge of high level tropical moisture
plume off the Pacific...an increase in precip chances will occur
Monday night through Tuesday night before decreasing again by
Wednesday with the passage of the upper trough and cold front.
With the clouds and increasing shower/thunder chances early next
week...will keep highs in the upper 50s for Monday...then cool into
the upper 40s and lower 50s Tuesday with the increase in rain and
the cold frontal passage.
&&
.AVIATION...(For the 12Z TAFs through 12Z Friday Morning)
Issued at 618 AM CDT THU OCT 31 2013
Uncertainty mainly deals with CIGS and VSBY bouncing around
categories within the stratiform rain. With the surface front
beginning to move southeast and some dryer air in the boundary
layer moving in behind the front, will trend a little more
optimistic with the CIGS and VSBY and keep them MVFR. Timing the
end of precip is not much different than the prev forecast. The
one concern is the RAP13 trending slower with the exit of the
overall system. Water vapor still suggests the upper wave will be
overhead by mid afternoon with the precip off to the east, so did
not slow the timing down as the RAP would have it.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...67
SHORT TERM...Wolters
LONG TERM...63
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS TOPEKA KS
619 AM CDT Thu Oct 31 2013
...AVIATION UPDATE...
.SHORT TERM...(Today and Tonight)
Issued at 358 AM CDT THU OCT 31 2013
Well finally the upper level trough is making progress east, and the
08z water vapor imagery shows the last and most impressive shortwave
lifting across the OK panhandle. Surface obs show the front has
moved into east central KS from Burlington to Eudora. Profiler data
suggests the 850MB front is a little further west near McPherson to
near Alma and into southwest IA.
Today will see an end to the wet and gloomy weather as the upper
level wave propagates east of the area. However this morning will be
wet across eastern KS. Most model guidance is showing decent mid
level frontogenesis along the 850 front with some moisture
lingering. Additionally there should be a decent shot of QG forcing
and PVA from the shortwave lifting out from the panhandles. So there
will be one last shot of widespread shower activity with some
embedded thunderstorms. Think that the rain will come to an end once
the 850 front and the associated frontogenesis pushes south and east
of the forecast area. This looks to occur by the early afternoon
with skies clearing out by the late afternoon hours. With recent
trends showing precip becoming more stratiform in nature, rainfall
rates may not be quite as high as yesterday, but with PWs still over
an inch across east central KS, there could still be around an inch
of additional rain accumulations. Therefore will maintain the flash
flood watch for areas along and southeast of the turnpike, although
the threat does not appear to be widespread. Areas further northwest
have not received as much rain and so will cancel the watch early
for these area.
Highs today will be tricky depending on when the clouds clear out.
Think north central KS will warm into the lower 60s while parts of
northeast and east central KS could stay in the middle 50s due to
cloud cover. Lows tonight are forecast to fall into the 30s and have
not made any big changes from the previous forecast. Models show dry
air advecting in from the west with dewpoint falling into the lower
30s. Clear skies should help with some radiational cooling. Winds
are forecast to remain from the west at 5 to 10 MPH overnight. Think
this along with the dry air advection are expected to mitigate any
widespread fog formation tonight. If it looks like winds will
decouple, later shifts may need to readdress this.
Wolters
.LONG TERM...(Friday through Wednesday)
Issued at 358 AM CDT THU OCT 31 2013
Next shortwave trough to move through in northwest flow aloft on
Friday will pass primarily north and east of the county warning area
so will keep mostly sunny skies with highs from the upper 50s
northern counties to the lower 60s south. Strong mixing will result
in gusty northwest winds of 15 to 25 mph but will gradually decrease
late in the afternoon. Although skies will be clear with decreasing
winds Friday night with saturated soils...will not insert fog into
forecast at this point as so mixing still evident with the high center
to the south and west of the CWA.
Will continue with a dry weekend forecast. Surface to start the day
Saturday will result in light winds and less mixing so will keep
cooler highs in the 50s before warming back into the low to middle
60s for Sunday as gusty south winds return ahead of deepening
leeside surface trough. Next chance for showers appears with the
developing llvl jet and resulting warm air advection Sunday night.
As the western trough advanced into the plains Monday night and
Tuesday and interacts with a surge of high level tropical moisture
plume off the Pacific...an increase in precip chances will occur
Monday night through Tuesday night before decreasing again by
Wednesday with the passage of the upper trough and cold front.
With the clouds and increasing shower/thunder chances early next
week...will keep highs in the upper 50s for Monday...then cool into
the upper 40s and lower 50s Tuesday with the increase in rain and
the cold frontal passage.
&&
.AVIATION...(For the 12Z TAFs through 12Z Friday Morning)
Issued at 618 AM CDT THU OCT 31 2013
Uncertainty mainly deals with CIGS and VSBY bouncing around
categories within the stratiform rain. With the surface front
beginning to move southeast and some dryer air in the boundary
layer moving in behind the front, will trend a little more
optimistic with the CIGS and VSBY and keep them MVFR. Timing the
end of precip is not much different than the prev forecast. The
one concern is the RAP13 trending slower with the exit of the
overall system. Water vapor still suggests the upper wave will be
overhead by mid afternoon with the precip off to the east, so did
not slow the timing down as the RAP would have it.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH until 1 PM CDT this afternoon FOR KSZ026-039-
040-054>056-058-059.
&&
$$
Happy Halloween!
SHORT TERM...Wolters
LONG TERM...63
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS CARIBOU ME
931 AM EDT THU OCT 31 2013
.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST OF THE AREA TODAY. STRONG LOW
PRESSURE WILL TRACK NORTHWEST OF MAINE FRIDAY DRAWING A COLD
FRONT ACROSS THE REGION. A WEAKER LOW WILL CROSS THE REGION
LATER SATURDAY INTO SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
VISIBLE SATELLITE SHOWS CLOUDS MOVING IN MORE QUICKLY THAN
REFLECTED IN THE EARLIER FORECAST. THE MAIN ADJUSTMENT WITH THIS
UPDATE WAS TO INCREASE CLOUD COVER THE REST OF THIS MORNING. THE
LATEST HRRR IS INDICATING THE STEADIEST RAIN SHOULD MOVE IN LATE
THIS AFTERNOON AND THE PREVIOUS FORECAST HAS THIS COVERED FAIRLY
WELL.
RAIN WILL SPREAD ACROSS THE AREA FROM WEST TO EAST THIS AFTERNOON
AND A SOUTHERLY BREEZE WILL INCREASE AS THE LOW APPROACHES. HIGHS
WILL REACH THE 50S DOWNEAST AND 40S OVER THE NORTH. TONIGHT WILL
BRING OCCASIONAL RAIN AND INCREASING SOUTH WINDS AS THE LOW CENTER
TRACKS INTO QUEBEC. LOW TEMPS TONIGHT WILL OCCUR EARLY THIS
EVENING. TEMPS WILL THEN RISE OVERNIGHT AS THE SOUTHERLY WIND
PULLS WARMER AIR NORTHWARD. A LOW LEVEL JET AROUND 70 KT AT 925
WILL BEGIN TO MOVE ACROSS THE COASTAL DOWNEAST REGION BY MORNING
WHERE WIND GUSTS MAY BEGIN TO APPROACH 40 MPH TOWARD MORNING. SOME
FOG AND MIST WILL LIKELY MOVE ONTO COASTAL AREAS LATE TONIGHT AS
THE WARMER AIR MOVES OVER THE COLDER WATERS.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
STRONG LOW PRESSURE WILL TRACK NORTHWEST OF MAINE FRIDAY...WITH A
COLD/OCCLUDED FRONT STARTING TO CROSS THE REGION DURING THE
AFTERNOON. MODELS INDICATE A STRONG LOW LEVEL JET CROSSING THE
REGION IN ADVANCE OF THE FRONT...WITH THE STRONGEST WINDS MOVING
ALONG THE DOWNEAST COAST. A HIGH WIND WATCH IS IN EFFECT FOR
CENTRAL/DOWNEAST PORTIONS OF THE FORECAST AREA FROM FRIDAY
MORNING THROUGH FRIDAY EVENING WITH THE LOW LEVEL JET. A HIGH
WIND WATCH IS IN EFFECT ACROSS NORTHERN AREAS FROM FRIDAY
AFTERNOON THROUGH FRIDAY EVENING WHERE THE COLD/OCCLUDED FRONT
WILL BREAK THE INVERSION ALLOWING THE STRONGER WINDS ALOFT TO MIX
TO THE SURFACE. OTHERWISE...AN AREA OF RAIN WILL CROSS THE REGION
FRIDAY MORNING THROUGH EARLY AFTERNOON THEN TAPER TO SHOWERS DURING
THE AFTERNOON. THE LOW AND FRONT WILL EXIT THROUGH THE MARITIMES
FRIDAY NIGHT. SKIES WILL REMAIN MOSTLY CLOUDY ACROSS NORTHERN
AREAS FRIDAY NIGHT...WITH DECREASING CLOUDS DOWNEAST. A WEAKER LOW
WILL BEGIN TO MOVE EAST ACROSS THE REGION LATER SATURDAY...WHILE
ANOTHER LOW BEGINS TO DEVELOP EAST OF THE GULF OF MAINE. CLOUD
COVER WILL INCREASE ACROSS THE REGION SATURDAY WITH A CHANCE OF
SHOWERS DURING THE AFTERNOON. TEMPERATURES WILL BE AT ABOVE NORMAL
LEVELS FRIDAY/SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THE OCEAN LOW WILL MOVE NORTHEAST SATURDAY NIGHT THROUGH SUNDAY
WITH A TROF EXTENDING BACK ACROSS THE FORECAST AREA. A CHANCE OF
RAIN/SNOW SHOWERS WILL PERSIST ACROSS NORTHERN AREAS SATURDAY NIGHT
INTO SUNDAY WITH A CHANCE OF RAIN SHOWERS DOWNEAST. HIGH PRESSURE
WILL BUILD EAST SUNDAY NIGHT...CROSS THE REGION MONDAY...THEN
MOVE EAST TUESDAY. MOSTLY CLEAR SKIES ARE EXPECTED ACROSS THE
REGION SUNDAY NIGHT THROUGH MONDAY...WITH PARTLY/MOSTLY SUNNY
SKIES TUESDAY. CLOUDS WILL THEN INCREASE WEDNESDAY WITH A CHANCE
OF SHOWERS. TEMPERATURES WILL BE AT SLIGHTLY BELOW NORMAL LEVELS
SUNDAY THROUGH TUESDAY...WITH NEAR NORMAL LEVEL TEMPERATURES
WEDNESDAY.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
NEAR TERM: VFR CONDITIONS ARE EXPECTED THROUGH MID AFTERNOON TODAY.
CONDITIONS WILL LOWER TO MVFR LATE THIS AFTERNOON THEN IFR
TONIGHT IN LOW CLOUDS AND SOME MIST AND FOG. SOUTHERLY WINDS WILL
INCREASE TODAY INTO TONIGHT. THERE IS A POTENTIAL FOR WIND SHEAR
LATE TONIGHT AS A LOW LEVEL SOUTHERLY JET AT 925 PUSHES NORTH
ACROSS THE AREA.
SHORT TERM: IFR/LIFR CONDITIONS ARE EXPECTED ACROSS THE REGION
EARLY FRIDAY...WITH OCCASIONAL MVFR CONDITIONS FRIDAY AFTERNOON.
STRONG WINDS WILL OCCUR ACROSS THE REGION FRIDAY INTO FRIDAY
EVENING...WITH LOW LEVEL WIND SHEAR ALSO A CONCERN. OCCASIONAL
MVFR CONDITIONS ARE POSSIBLE ACROSS NORTHERN AREAS FRIDAY NIGHT
WITH VFR CONDITIONS DOWNEAST. CONDITIONS WILL LOWER TO MVFR/IFR
LEVELS ACROSS THE REGION SATURDAY...WITH SIMILAR CONDITIONS
PERSISTING INTO EARLY SUNDAY. VFR CONDITIONS WILL DEVELOP SUNDAY
AFTERNOON...THEN PERSIST THROUGH MONDAY.
&&
.MARINE...
NEAR TERM: SOUTHERLY WINDS WILL INCREASE LATER TODAY INTO TONIGHT.
A GALE WARNING IS BEING ISSUED BEGINNING AT 2 AM FRIDAY FOR SOUTH
WINDS GUSTING OVER 35 KT LATE TONIGHT. SEAS ARE EXPECTED TO RISE
ABOVE 10 FT IN RESPONSE TO THE SOUTH WINDS LATE TONIGHT.
SHORT TERM: A GALE WARNING IS IN EFFECT FOR THE WATERS FRIDAY
THROUGH MUCH OF FRIDAY NIGHT WITH GUSTS OF 40 TO 45 KNOTS EXPECTED.
SMALL CRAFT ADVISORY CONDITIONS ARE THEN EXPECTED THROUGH MUCH OF
LATER FRIDAY NIGHT INTO MONDAY. VISIBILITIES WILL BE REDUCED IN RAIN
AND FOG FRIDAY. SHOWERS ARE THEN POSSIBLE SATURDAY AFTERNOON INTO
SUNDAY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...HIGH WIND WATCH FROM FRIDAY AFTERNOON THROUGH FRIDAY EVENING
FOR MEZ001>006-010.
HIGH WIND WATCH FROM FRIDAY MORNING THROUGH FRIDAY EVENING FOR
MEZ011-015>017-029>032.
MARINE...GALE WARNING FROM 2 AM FRIDAY TO 2 AM EDT SATURDAY FOR
ANZ050>052.
&&
$$
NEAR TERM...BLOOMER/DUDA
SHORT TERM...NORCROSS
LONG TERM...NORCROSS
AVIATION...BLOOMER/DUDA/NORCROSS
MARINE...BLOOMER/DUDA/NORCROSS
AREA FORECAST DISCUSSION
NWS JACKSON MS
1027 AM CDT THU OCT 31 2013
.UPDATE...
UPDATED ALL PRODUCTS FOR TORNADO WATCH WORDING INCLUSION AND MOVED
UP FLASH FLOOD WATCH START TIME TO NOW. A NEW HAZARDOUS WEATHER
OUTLOOK AND SUPPORTING GRAPHICS WILL BE UPDATED SHORTLY TO REFLECT
THE CURRENT TRENDS AND EXPECTED EVOLUTION THAT ARE DISCUSSED BELOW.
.DISCUSSION...
LIFT FROM A LEAD SHORTWAVE IN COMBINATION WITH THE BEGINNING
INFLUENCE OF LIFT FROM THE MAIN TROUGH FORCING STILL BACK ACROSS
TEXAS/LOUISIANA HAS ALLOWED FOR A HEAVY RAIN SHIELD TO DEVELOP
ACROSS THE DELTA WITH A STRONGER CONVECTIVE AXIS EXTENDING SOUTHWEST
TOWARDS LAKE CHARLES. THIS LEAD SHORTWAVE HAS COME IN STRONGER AND
THUS THE HEAVY RAIN AND CONVECTIVE BANDING TIMING IS FASTER FOR THIS
MORNING. THE STRATIFORM RAIN SHIELD NORTH OF I-20 HAS NULLIFIED THE
SEVERE STORM RISK THERE. GRADIENT WINDS WILL STILL BE GUSTY AS OBS
THIS MORNING SHOW 20-25 KT GUSTS. ITS NOT IMPOSSIBLE FOR HIGHER WIND
GUSTS TO OCCUR LATE MRNG/AFTN TO 35 KT (40 MPH) WITH SUCH SATURATED
SOIL FOR SPORADIC TREES TO COME DOWN, HOWEVER. THE BETTER RISK FOR
ANY STRONG TO SEVERE STORM WILL BE ALONG AND SOUTH OF I-20 CLOSER TO
A CAPE RESERVOIR POOL ACROSS SOUTHERN LOUISIANA.
A SMALL PORTION OF LOUISIANA AND SOUTHWEST MS IS UNDER A TORNADO
WATCH THROUGH 2PM THIS AFTERNOON. WHILE THE TORNADO RISK IS LOW WITH
LACK OF ANY INSTABILITY PER MESOANALYSIS, THE AMOUNT OF 0-1 KM SRH
REMAINS HIGH />500 M2/S2/. THIS ENVIRONMENT SUPPORTS A NON-ZERO RISK
FOR TORNADOES BUT THE LIKELIHOOD IS SMALL. NONE-THE-LESS, WE WILL
CONTINUE TO MONITOR ANY DEEPER CONVECTIVE CELL THAT COULD TAKE
ADVANTAGE IN THIS SET-UP.
HAVE MOVED UP THE START TIME OF THE FLASH FLOOD WATCH TO NOW WITH
THE AREAS REMAINING THE SAME. HI-RES AND HRRR OUTPUT THIS MORNING
CONTINUE TO SUGGEST WIDESPREAD 1-3 INCHES WITH NARROW BANDS OF 3 TO
4 INCHES DEPENDING ON WHERE HIGHER CONVECTIVE CELLS TRAIN. HOWEVER,
IT SHOULD BE STRESSED THAT WITH SUCH ANOMALOUSLY HIGH PWATS OF 1.8
TO 2" AND DUAL-POL RADAR INDICATING 2-4" INSTANTANEOUS HOURLY PRECIP
RATES...RAIN FALL IN NE LOUISIANA AND ACROSS SW TO SOUTH MISSISSIPPI
WILL HAVE THE POSSIBILITY OF HAVING NARROW BANDS OF LOCALLY 4-5"
POSSIBLE IN A SHORT AMOUNT OF TIME. ESPECIALLY SINCE THE FORCING AND
THE RESULTANT ASCENT OF THE MAIN TROUGH AXIS REMAINS BACK TO OUR
WEST.
HRRR HAS A DECENT HANDLE ON PRECIP LOCATION CURRENTLY BUT THINK IT
IS TO FAST AS TIME PROGRESSES ESPECIALLY GIVEN AREA OF ASCENT SEEN
IN WATER VAPOR AND RADAR IMAGERY STILL REMAINING BACK ACROSS TEXAS.
FEEL MORE COMFORTABLE GOING TOWARDS 6Z ARW WRF WHICH IS SLOWER THAN
THE HRRR. THE HEAVY RAIN AXIS WILL LINGER ACROSS LA/MS RIVER THROUGH
EARLY AFTERNOON, BE NEAR JACKSON EARLY AFTERNOON TO MID AFTERNOON,
AND IN EAST MS TOWARDS HATTIESBURG BY LATE AFTERNOON TO EARLY
EVENING. RAIN WILL LINGER BEHIND THE MAIN AXIS AS THE ACTUAL FRONT
MOVES THROUGH BEHIND THE MAIN RAIN AXIS. THIS OVERALL TIMING IS A
TOUCH FASTER THAN PREVIOUS FORECAST WITH RAIN LIGHTENING UP
POSSIBLY ACROSS THE METRO BY 7PM FOR HALLOWEEN ACTIVITIES. UPDATED
HWO/GRAPHICS WILL BE OUT SHORTLY TO REFLECT NEW TIMING AND HAZARD
AREAS.
/ALLEN/
&&
.AVIATION...MAINLY MVFR CONDITIONS ANTICIPATED THROUGH MUCH OF THE
DAY ACROSS THE AERODROME AS RAIN AND EMBEDDED THUNDERSTORMS
GRADUALLY PUSH INTO THE HEART OF THE REGION. THUNDERSTORMS THROUGH
EARLY THIS EVENING WILL BE MORE NUMEROUS SOUTH OF INTERSTATE TWENTY
AND A FEW OF THESE COULD CONTAIN VERY GUSTY WINDS. AWAY FROM STORMS
ANTICIPATE GUSTY SOUTH WINDS OVER 20 KTS AT TIMES. THE STRONGEST
WINDS WILL BE THROUGH EARLY AFTERNOON AT GLH/GWO. POCKETS OF IFR
CONDITIONS WILL BE POSSIBLE IN ALL AREAS FOR ONE TO TWO HOURS AT A
TIME DURING THE DAY AS THE POCKETS OF HEAVIEST PRECIPITATION MOVE
OVER THE STATION.
PRECIPITATION SHOULD BE GRADUALLY CLEARING TO THE EAST THROUGH THE
NIGHT TONIGHT...ALTHOUGH MVFR TO PATCHY IFR CONDITIONS MAY LINGER IN
SOME FASHION UNTIL MORNING. THE LATTER WILL ESPECIALLY BE THE CASE
ACROSS EASTERN PORTIONS OF MS. /BB/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 76 53 74 46 / 96 61 11 0
MERIDIAN 78 56 74 43 / 95 94 17 0
VICKSBURG 76 50 74 46 / 100 37 8 0
HATTIESBURG 78 63 78 48 / 57 100 31 0
NATCHEZ 76 52 73 49 / 100 39 9 0
GREENVILLE 73 49 73 47 / 100 11 7 0
GREENWOOD 72 49 73 47 / 98 37 8 0
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...FLASH FLOOD WATCH THROUGH THIS EVENING FOR MSZ018-019-025>045-
047>050-053>055-059>062.
WIND ADVISORY UNTIL 5 PM CDT THIS AFTERNOON FOR MSZ018-019-025-
034-035-040-041.
LA...FLASH FLOOD WATCH THROUGH THIS EVENING FOR LAZ007>009-015-016-
023>026.
WIND ADVISORY UNTIL 5 PM CDT THIS AFTERNOON FOR LAZ007>009-015-
016-023>026.
AR...FLASH FLOOD WATCH THROUGH THIS EVENING FOR ARZ074-075.
WIND ADVISORY UNTIL 5 PM CDT THIS AFTERNOON FOR ARZ074-075.
&&
$$
ALLEN
AREA FORECAST DISCUSSION
NWS JACKSON MS
937 AM CDT THU OCT 31 2013
.UPDATE...
UPDATED ALL PRODUCTS FOR TORNADO WATCH WORDING INCLUSION AND MOVED
UP FLASH FLOOD WATCH START TIME TO NOW. A NEW HAZARDOUS WEATHER
OUTLOOK AND SUPPORTING GRAPHICS WILL BE UPDATED SHORTLY TO REFLECT
THE CURRENT TRENDS AND EXPECTED EVOLUTION THAT ARE DISCUSSED BELOW.
.DISCUSSION...
LIFT FROM A LEAD SHORTWAVE IN COMBINATION WITH THE BEGINNING
INFLUENCE OF LIFT FROM THE MAIN TROUGH FORCING STILL BACK ACROSS
TEXAS/LOUISIANA HAS ALLOWED FOR A HEAVY RAIN SHIELD TO DEVELOP
ACROSS THE DELTA WITH A STRONGER CONVECTIVE AXIS EXTENDING SOUTHWEST
TOWARDS LAKE CHARLES. THIS LEAD SHORTWAVE HAS COME IN STRONGER AND
THUS THE HEAVY RAIN AND CONVECTIVE BANDING TIMING IS FASTER FOR THIS
MORNING. THE STRATIFORM RAIN SHIELD NORTH OF I-20 HAS NULLIFIED THE
SEVERE STORM RISK THERE. GRADIENT WINDS WILL STILL BE GUSTY AS OBS
THIS MORNING SHOW 20-25 KT GUSTS. ITS NOT IMPOSSIBLE FOR HIGHER WIND
GUSTS TO OCCUR LATE MRNG/AFTN TO 35 KT (40 MPH) WITH SUCH SATURATED
SOIL FOR SPORADIC TREES TO COME DOWN, HOWEVER. THE BETTER RISK FOR
ANY STRONG TO SEVERE STORM WILL BE ALONG AND SOUTH OF I-20 CLOSER TO
A CAPE RESERVOIR POOL ACROSS SOUTHERN LOUISIANA.
A SMALL PORTION OF LOUISIANA AND SOUTHWEST MS IS UNDER A TORNADO
WATCH THROUGH 2PM THIS AFTERNOON. WHILE THE TORNADO RISK IS LOW WITH
LACK OF ANY INSTABILITY PER MESOANALYSIS, THE AMOUNT OF 0-1 KM SRH
REMAINS HIGH />500 M2/S2/. THIS ENVIRONMENT SUPPORTS A NON-ZERO RISK
FOR TORNADOES BUT THE LIKELIHOOD IS SMALL. NONE-THE-LESS, WE WILL
CONTINUE TO MONITOR ANY DEEPER CONVECTIVE CELL THAT COULD TAKE
ADVANTAGE IN THIS SET-UP.
HAVE MOVED UP THE START TIME OF THE FLASH FLOOD WATCH TO NOW WITH
THE AREAS REMAINING THE SAME. HI-RES AND HRRR OUTPUT THIS MORNING
CONTINUE TO SUGGEST WIDESPREAD 1-3 INCHES WITH NARROW BANDS OF 3 TO
4 INCHES DEPENDING ON WHERE HIGHER CONVECTIVE CELLS TRAIN. HOWEVER,
IT SHOULD BE STRESSED THAT WITH SUCH ANOMALOUSLY HIGH PWATS OF 1.8
TO 2" AND DUAL-POL RADAR INDICATING 2-4" INSTANTANEOUS HOURLY PRECIP
RATES...RAIN FALL IN NE LOUISIANA AND ACROSS SW TO SOUTH MISSISSIPPI
WILL HAVE THE POSSIBILITY OF HAVING NARROW BANDS OF LOCALLY 4-5"
POSSIBLE IN A SHORT AMOUNT OF TIME. ESPECIALLY SINCE THE FORCING AND
THE RESULTANT ASCENT OF THE MAIN TROUGH AXIS REMAINS BACK TO OUR
WEST.
HRRR HAS A DECENT HANDLE ON PRECIP LOCATION CURRENTLY BUT THINK IT IS
TO FAST AS TIME PROGRESSES ESPECIALLY GIVEN AREA OF ASCENT SEEN IN
WATER VAPOR AND RADAR IMAGERY STILL REMAINING BACK ACROSS TEXAS.
FEEL MORE COMFORTABLE GOING TOWARDS 6Z ARW WRF WHICH IS SLOWER THAN
THE HRRR. THE HEAVY RAIN AXIS WILL LINGER ACROSS LA/MS RIVER THROUGH
EARLY AFTERNOON, BE NEAR JACKSON EARLY AFTERNOON TO MID AFTERNOON,
AND IN EAST MS TOWARDS HATTIESBURG BY LATE AFTERNOON TO EARLY
EVENING. RAIN WILL LINGER BEHIND THE MAIN AXIS AS THE ACTUAL FRONT
MOVES THROUGH BEHIND THE MAIN RAIN AXIS. THIS OVERALL TIMING IS A
TOUCH FASTER THAN PREVIOUS FORECAST WITH RAIN LIGHTENING UP
POSSIBLY ACROSS THE METRO BY 7PM FOR HALLOWEEN ACTIVITIES. UPDATED
HWO/GRAPHICS WILL BE OUT SHORTLY TO REFLECT NEW TIMING AND HAZARD
AREAS.
/ALLEN/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 76 53 74 46 / 96 61 11 0
MERIDIAN 78 56 74 43 / 95 94 17 0
VICKSBURG 76 50 74 46 / 100 37 8 0
HATTIESBURG 78 63 78 48 / 57 100 31 0
NATCHEZ 76 52 73 49 / 100 39 9 0
GREENVILLE 73 49 73 47 / 100 11 7 0
GREENWOOD 72 49 73 47 / 98 37 8 0
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...FLASH FLOOD WATCH THROUGH THIS EVENING FOR MSZ018-019-025>045-
047>050-053>055-059>062.
WIND ADVISORY UNTIL 5 PM CDT THIS AFTERNOON FOR MSZ018-019-025-
034-035-040-041.
LA...FLASH FLOOD WATCH THROUGH THIS EVENING FOR LAZ007>009-015-016-
023>026.
WIND ADVISORY UNTIL 5 PM CDT THIS AFTERNOON FOR LAZ007>009-015-
016-023>026.
AR...FLASH FLOOD WATCH THROUGH THIS EVENING FOR ARZ074-075.
WIND ADVISORY UNTIL 5 PM CDT THIS AFTERNOON FOR ARZ074-075.
&&
$$
ALLEN
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
610 AM CDT THU OCT 31 2013
.AVIATION...12Z TAFS FOR KOMA...KLNK AND KOFK. COULD SEE TEMPORARY
MVFR FOG CONDITIONS THIS MORNING THROUGH ABOUT 14Z. COULD ALSO SEE
TEMPORARY IFR CEILINGS AT KOMA THROUGH THE SAME PERIOD.
OTHERWISE...CALM OR LIGHT AND VARIABLE WINDS BECOME WEST THIS
MORNING...THEN NORTHWEST BY 15 TO 17Z. BY THEN...COULD ALSO SEE
GUSTS THAT RANGE FROM 18 TO 24 KNOTS THROUGH THE AFTERNOON...BUT
GUSTS DIMINISH BY 23-00Z.
DEWALD
&&
.PREV DISCUSSION... /ISSUED 255 AM CDT THU OCT 31 2013/
DISCUSSION...
SKIES HAD CLEARED ACROSS ALL BUT THE SOUTHEAST PORTION OF THE
FORECAST AREA AT 07Z WITH UPPER TROUGH AXIS STILL OVER THE WESTERN
PLAINS. WV LOOP SHOWING STRONG VORT MAX COMING OUT OF NORTHEAST
NEW MEXICO WHICH MODELS LIFT TOWARD THE LOWER MISSOURI VALLEY
DURING THE DAY. THIS WILL LIKELY MAINTAIN SOME CLOUD COVER OVER
THE SOUTHEAST UNTIL PASSAGE SOMETIME THIS AFTERNOON WITH
INCREASING CLOUDS ELSEWHERE ACROSS THE AREA. HRRR SUGGEST SOME
CHANCE OF SHOWERS FOR FAR SOUTHEAST NEBRASKA AND SOUTHWEST IOWA SO
HAVE PLACED LOW POPS THERE THROUGH THE MORNING. PATCHY FOG MENTION
FOR PARTS OF THE NORTHEAST AND EAST CENTRAL AREAS.
WINDY CONDITIONS MOVE INTO THE AREA ON FRIDAY AS UPPER TROUGH AXIS
SHIFTS EAST OF THE AREA...OTHERWISE GENERALLY DRY WITH SEASONAL
TEMPERATURES EXPECTED INTO SATURDAY.
EXTENDED PERIOD STILL LOOKS TO TURN ACTIVE EARLY NEXT WEEK AFTER
A MILD START ON SUNDAY. PATTERN SIMILAR TO THE RECENT SYSTEM AS
ANOTHER DEEP TROUGH DEVELOPS OVER THE WESTERN CONUS WITH A COLD
FRONT OVER EASTERN PARTS OF KANSAS AND NEBRASKA MONDAY NIGHT INTO
TUESDAY. SETUP PROVIDES ANOTHER CHANCE OF PRECIP FOR THE AREA WITH
A MIX OF RAIN AND SNOW IN PARTS OF THE NORTHEAST WHERE COLDER
TEMPERATURES EXPECTED THIS TIME AROUND.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1122 AM EDT THU OCT 31 2013
.SYNOPSIS...
A WARM FRONT WILL GENERATE SHOWERS TODAY PRIMARILY THROUGH MID
AFTERNOON. A STRONG COLD FRONT WILL BRING ANOTHER ROUND OF SHOWERS
LATE TONIGHT THROUGH LATE FRIDAY MORNING, ALONG WITH STRONG
GUSTY WINDS. FRIDAY AFTERNOON THROUGH SATURDAY MORNING WILL BE
PRIMARILY DRY, BEFORE SCATTERED SHOWERS IMPACT THE AREA SATURDAY
AFTERNOON.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1120 AM UPDATE...SHOWERS NOW CONFINED TO AREAS PRIMARILY EAST/NORTH
OF THE BGM AREA. ACTIVITY CONTINUES MOVING THROUGH AT A GOOD PACE
AND EXPECT THE WIDESPREAD ACTIVITY TO BE NEARLY OVER BY EARLY
AFTERNOON EXCEPT FOR ONEIDA COUNTY. FOR THE REMAINDER OF THE
DAYLIGHT HOURS INTO EARLY EVENING COVERAGE WILL ONLY BE SCATTERED.
830 AM UPDATE...LOCAL RADARS SHOW SHOWERS OVER THE CENTRAL
SOUTHERN TIER AND FINGER LAKES REGION. THIS ACTIVITY IS MOVING
QUICKLY ACROSS CENTRAL NY AND IS ASSOCIATED WITH AN AREA OF STRONG
ISENTROPIC LIFT THAT WILL MOVE THROUGH THE REGION BY EARLY
AFTERNOON. SPED UP POPS THIS MORNING TO REFLECT CURRENT
CONDITIONS. ASSOCIATED LIKELY/CATEGORICAL POPS WITH BAND OF LIFT
ASSOCIATED WITH WARM FRONT THEN DROPPED POPS BACK INTO SCATTERED
COVERAGE ONCE IT PASSES. WIDESPREAD SHOWERS MAY LINGER IN THE
WESTERN CATSKILLS AND NRN CWA INTO THE MID AFTERNOON.
330 AM UPDATE... UL LOW SITTING UP OVR THE DAKOTAS AND EJECTING
SLOWLY TO THE EAST. SIGNIFICANT MOISTURE IS CREEPING UP AHD OF LOW
WITH PW VALUES INCRSG TO 40 MM (1.5 INCHES) OVR THE MID-MS VLY.
THIS IS PROGGED TO WORK UP INTO THE REGION LATE THIS AFTN.
04Z HAND ANALYSIS PLACES WMFNT EXTENDING FM SFC LOW IN IOWA INTO NRN
INDIANA AND OHIO AND SLOWLY HEADING NORTH. DWPTS SOUTH OF THE BNDRY
IN THE MID-ATLANTIC STATES ARE IN THE 50S AND WL WORK UP THIS WAY
THIS AFTN.
AREA OF MODERATE TO HVY RAIN ACRS LWR MICHIGAN DVLPNG IN VICINITY OF
SFC WMFNT ON NOSE OF LLJ. LATEST HRRR RUN BRINGS PCPN INTO WRN ZONES
BY 11Z AND OVRSPRDS MOST OF THE REGION BY AFTN. MAY BE BROKEN ACRS
SRN SXNS THIS AFTN IN THE FORM OF SCTD SHOWERS BASED ON WHAT IS
CURRENTLY GOING ON SOUTH OF SFC WMFNT, THUS WL KEEP JUST SCTD SHOWER
MENTION ALONG AND SOUTH OF THE NRN TIER OF PA.
AFTN MAXES WL TOP OUT IN THE L/M 60S AS 925MB TEMPS CLIMB UP TO ARND
10-12C TDA. THIS IS ALL COURTESY OF WAA THAT WL COMMENCE ACRS THE
REGION AS WMFNT PASSES THRU. CLDY SKIES EXPECTED FOR MOST OF THE DAY
WITH SHOWER ACTIVITY LKLY KEEPING TEMPS FM GETTING OUT OF CONTROL.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
330 AM UPDATE...
PHASING OF S/WVS EXPECTED TONIGHT RESULTING IN DEEPENING SFC LOW
ACRS THE GREAT LKS. H8 LLJ GETS CRANKING BY MIDNIGHT ACRS THE AREA
TO +60KTS THEN ABV 70KTS BY 09Z. BASED ON TRACK OF APPROX 980MB SFC
LOW ACRS SRN ONTARIO BY ALL MODELS, WITH 00Z NAM BEING A TOUCH
FURTHER NORTH, HV DECIDED TO UPGRADE TO HIGH WIND WARNING. BASED ON
LOCAL SYNOPTIC WIND STUDY 6-HR RISE/FALL COUPLET LOOKS TO BE IN THE
BALLPARK FOR HIGH WIND EVENT AND CONFIDENCE IS THERE THAT EXISTING
CNTYS IN WATCH WILL SEE HIGH WINDS AFTER MIDNIGHT TONIGHT. WL ALLOW
DAYSHIFT TO EVALUATE THE NEED FOR WIND ADVISORY ACRS RMNG AREAS TDA.
GIVEN THE STRENGTHENING LLJ AND PHASING OF VORT MAXES TONIGHT EXPECT
OCNL MODERATE SHOWERS LATE WITH QPF AMNTS ACRS THE FAR NORTH IN
VICINITY OF WMFNT APPCHG 1 INCH THRU 12Z FRIDAY. ELSEWHERE EXPECT
ARND 0.50 INCHES.
THO INSTABILITY IS VRY POOR THRU 12Z FRIDAY HV ADDED IN AN ISOLD
THUNDER MENTION AS SHOWALTERS/LI VALUES DIP BLO 0C BTWN 09Z AND 15Z
FRIDAY. CAPES VALUES LOOK TO BE PRETTY PUNY DRG THIS TIME WITH JUST
A COUPLE HUNDRED JOULES, HWVR DYNAMICS ARE EXTREMELY IMPRESSIVE AND
LOW-LVL LR ARE STEEP JUST ALONG AND AHD OF FRONT THUS THINK THAT
THUNDER AT LEAST DESERVES A MENTION, ESPECIALLY CONSIDERING
LIGHTNING STRIKES CURRENTLY OVR LK ERIE.
FROPA LOOKS TO OCCUR SOMETIME FRI MRNG/AFTN WITH HIGH TEMPS ONCE
AGAIN RISING INTO THE 60S ACRS MOST OF THE AREA, THO EXTRM WRN ZONES
MAY TOP OUT ARND 60F. APPEARS THAT THERE WILL BE A SHARP GRADIENT TO
PCPN WITH SHOWERS ENDING IN AREAS WEST OF I-81 AT 18Z AND LINGERING
ACRS ERN ZONES FOR ANOTHER HR OR TWO AFT THIS TIME. CAA WL BE
DELAYED UNTIL THE VRY END OF THE SHORT TERM WITH OVRNGT MINS AND
AFTN MAXES STILL ABV NORMAL FOR SATURDAY.
ANOTHER TROF/ASSOC SFC LOW WL MV INTO AREA FM THE NW BY 12Z
SATURDAY. WINDS WL BCM SRLY AHD OF THIS SFC SYSTEM AND QUICKLY SHIFT
ARND TO THE NW AS LOPRES PASSES ON SATURDAY. THIS WL SET THE STAGE
FOR LK EFFECT SHOWERS ON SAT AFTN AND EVENTUALLY A MIX WITH AND
CHANGE OVR TO SNOW ON SUN MRNG. HV MADE NO CHGS TO THESE GRIDS AT
THIS TIME DUE TO NEAR TERM CHALLENGES.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
2 AM UPDATE...
JUST MINOR CHANGES AND STILL BASED ON WPC GUIDANCE. PROGRESSIVE
PATTERN WITH UPPER LEVEL TROF EXITING THIS WEEKEND THEN UL HEIGHTS
BUILD AGAIN WITH A LARGE SFC HIGH PRESSURE MONDAY TO WED. THURSDAY
MORE SHOWERS AS A COLD FRONT AND TROF APPROACH.
PREVIOUS DISCUSSION...
A QUIET PD IS IN STORE FOR THE FCST AREA AFTER THE DEPARTURE OF
THIS WEEKEND`S SYSTEM. LAKE ENHANCED -SHSN DUE TO DEPARTING UPR
LVL TROF WILL TAPER OFF ON SUNDAY...WITH SFC RIDGING AND RAPIDLY
RISING HGTS EARLY NXT WEEK AS ANOTHER DEEP TROF DIGS INTO THE
CNTRL U.S.. THIS SYSTEM WILL BEGIN TO APPROACH THE FCST AREA LATE
IN THE FCST PD. MAXES MODERATING FROM THE U40S ON MONDAY TO THE
MID 50S BY WED.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
7 AM UPDATE...
SATURATED LOW LEVELS DUE TO SOUTH WINDS AHEAD OF A WARM FRONT HAVE
BROUGHT IFR CONDITIONS TO BGM AND MVFR TO AVP AND ITH. MORE
MOISTURE AND SHOWERS IN WRN NY AND WRN PA WILL MOVE THROUGH
BETWEEN 13 AND 17Z WITH MVFR CONDITIONS AND POSSIBLE IFR
ESPECIALLY AT BGM AND ITH. BY 18Z SOUTH CENT NY AND AVP SHOULD BE
DRY AND IN THE WARM SECTOR. CIGS SHOULD LIFT SOME BUT REMAIN MVFR.
VSBYS WILL RETURN TO VFR. AT SYR AND RME SHOWERS WILL LINGER OFF
AND ON ALL DAY WITH MAINLY MVFR CONDITIONS. THIS EVENING SHOWERS
COME BACK IN EVERYWHERE.
LIGHT SE TO S WINDS WILL INCREASE TO 10 TO 15 WITH HIGHER GUSTS
TODAY AND CONTINUE INTO TONIGHT.
OUTLOOK...
FRI/FRI NGT...MVFR/IFR BECOMING VFR MIDDAY FRIDAY AS RAIN ENDS.
STRONG GUSTY SW TO W WINDS FRI MRNG...ESPECIALLY KSYR-KRME.
SAT/SAT NGT...MVFR IN SHRA/SHSN PRIMARILY CNTRL NY.
SUN...MVFR EARLY CNTRL NY IN -SHRA/-SHSN...IMPRVG TO VFR.
MON...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...HIGH WIND WARNING FROM 2 AM TO 2 PM EDT FRIDAY FOR NYZ009-
015>018-036-037.
&&
$$
SYNOPSIS...PVN
NEAR TERM...PVN/RRM
SHORT TERM...PVN
LONG TERM...TAC
AVIATION...TAC
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
834 AM EDT THU OCT 31 2013
.SYNOPSIS...
A WARM FRONT WILL GENERATE SHOWERS TODAY PRIMARILY THROUGH MID
AFTERNOON. A STRONG COLD FRONT WILL BRING ANOTHER ROUND OF SHOWERS
LATE TONIGHT THROUGH LATE FRIDAY MORNING, ALONG WITH STRONG
GUSTY WINDS. FRIDAY AFTERNOON THROUGH SATURDAY MORNING WILL BE
PRIMARILY DRY, BEFORE SCATTERED SHOWERS IMPACT THE AREA SATURDAY
AFTERNOON.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
830 AM UPDATE...LOCAL RADARS SHOW SHOWERS OVER THE CENTRAL
SOUTHERN TIER AND FINGER LAKES REGION. THIS ACTIVITY IS MOVING
QUICKLY ACROSS CENTRAL NY AND IS ASSOCIATED WITH AN AREA OF STRONG
ISENTROPIC LIFT THAT WILL MOVE THROUGH THE REGION BY EARLY
AFTERNOON. SPED UP POPS THIS MORNING TO REFLECT CURRENT
CONDITIONS. ASSOCIATED LIKELY/CATEGORICAL POPS WITH BAND OF LIFT
ASSOCIATED WITH WARM FRONT THEN DROPPED POPS BACK INTO SCATTERED
COVERAGE ONCE IT PASSES. WIDESPREAD SHOWERS MAY LINGER IN THE
WESTERN CATSKILLS AND NRN CWA INTO THE MID AFTERNOON.
330 AM UPDATE... UL LOW SITTING UP OVR THE DAKOTAS AND EJECTING
SLOWLY TO THE EAST. SIGNIFICANT MOISTURE IS CREEPING UP AHD OF LOW
WITH PW VALUES INCRSG TO 40 MM (1.5 INCHES) OVR THE MID-MS VLY.
THIS IS PROGGED TO WORK UP INTO THE REGION LATE THIS AFTN.
04Z HAND ANALYSIS PLACES WMFNT EXTENDING FM SFC LOW IN IOWA INTO NRN
INDIANA AND OHIO AND SLOWLY HEADING NORTH. DWPTS SOUTH OF THE BNDRY
IN THE MID-ATLANTIC STATES ARE IN THE 50S AND WL WORK UP THIS WAY
THIS AFTN.
AREA OF MODERATE TO HVY RAIN ACRS LWR MICHIGAN DVLPNG IN VICINITY OF
SFC WMFNT ON NOSE OF LLJ. LATEST HRRR RUN BRINGS PCPN INTO WRN ZONES
BY 11Z AND OVRSPRDS MOST OF THE REGION BY AFTN. MAY BE BROKEN ACRS
SRN SXNS THIS AFTN IN THE FORM OF SCTD SHOWERS BASED ON WHAT IS
CURRENTLY GOING ON SOUTH OF SFC WMFNT, THUS WL KEEP JUST SCTD SHOWER
MENTION ALONG AND SOUTH OF THE NRN TIER OF PA.
AFTN MAXES WL TOP OUT IN THE L/M 60S AS 925MB TEMPS CLIMB UP TO ARND
10-12C TDA. THIS IS ALL COURTESY OF WAA THAT WL COMMENCE ACRS THE
REGION AS WMFNT PASSES THRU. CLDY SKIES EXPECTED FOR MOST OF THE DAY
WITH SHOWER ACTIVITY LKLY KEEPING TEMPS FM GETTING OUT OF CONTROL.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
330 AM UPDATE...
PHASING OF S/WVS EXPECTED TONIGHT RESULTING IN DEEPENING SFC LOW
ACRS THE GREAT LKS. H8 LLJ GETS CRANKING BY MIDNIGHT ACRS THE AREA
TO +60KTS THEN ABV 70KTS BY 09Z. BASED ON TRACK OF APPROX 980MB SFC
LOW ACRS SRN ONTARIO BY ALL MODELS, WITH 00Z NAM BEING A TOUCH
FURTHER NORTH, HV DECIDED TO UPGRADE TO HIGH WIND WARNING. BASED ON
LOCAL SYNOPTIC WIND STUDY 6-HR RISE/FALL COUPLET LOOKS TO BE IN THE
BALLPARK FOR HIGH WIND EVENT AND CONFIDENCE IS THERE THAT EXISTING
CNTYS IN WATCH WILL SEE HIGH WINDS AFTER MIDNIGHT TONIGHT. WL ALLOW
DAYSHIFT TO EVALUATE THE NEED FOR WIND ADVISORY ACRS RMNG AREAS TDA.
GIVEN THE STRENGTHENING LLJ AND PHASING OF VORT MAXES TONIGHT EXPECT
OCNL MODERATE SHOWERS LATE WITH QPF AMNTS ACRS THE FAR NORTH IN
VICINITY OF WMFNT APPCHG 1 INCH THRU 12Z FRIDAY. ELSEWHERE EXPECT
ARND 0.50 INCHES.
THO INSTABILITY IS VRY POOR THRU 12Z FRIDAY HV ADDED IN AN ISOLD
THUNDER MENTION AS SHOWALTERS/LI VALUES DIP BLO 0C BTWN 09Z AND 15Z
FRIDAY. CAPES VALUES LOOK TO BE PRETTY PUNY DRG THIS TIME WITH JUST
A COUPLE HUNDRED JOULES, HWVR DYNAMICS ARE EXTREMELY IMPRESSIVE AND
LOW-LVL LR ARE STEEP JUST ALONG AND AHD OF FRONT THUS THINK THAT
THUNDER AT LEAST DESERVES A MENTION, ESPECIALLY CONSIDERING
LIGHTNING STRIKES CURRENTLY OVR LK ERIE.
FROPA LOOKS TO OCCUR SOMETIME FRI MRNG/AFTN WITH HIGH TEMPS ONCE
AGAIN RISING INTO THE 60S ACRS MOST OF THE AREA, THO EXTRM WRN ZONES
MAY TOP OUT ARND 60F. APPEARS THAT THERE WILL BE A SHARP GRADIENT TO
PCPN WITH SHOWERS ENDING IN AREAS WEST OF I-81 AT 18Z AND LINGERING
ACRS ERN ZONES FOR ANOTHER HR OR TWO AFT THIS TIME. CAA WL BE
DELAYED UNTIL THE VRY END OF THE SHORT TERM WITH OVRNGT MINS AND
AFTN MAXES STILL ABV NORMAL FOR SATURDAY.
ANOTHER TROF/ASSOC SFC LOW WL MV INTO AREA FM THE NW BY 12Z
SATURDAY. WINDS WL BCM SRLY AHD OF THIS SFC SYSTEM AND QUICKLY SHIFT
ARND TO THE NW AS LOPRES PASSES ON SATURDAY. THIS WL SET THE STAGE
FOR LK EFFECT SHOWERS ON SAT AFTN AND EVENTUALLY A MIX WITH AND
CHANGE OVR TO SNOW ON SUN MRNG. HV MADE NO CHGS TO THESE GRIDS AT
THIS TIME DUE TO NEAR TERM CHALLENGES.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
2 AM UPDATE...
JUST MINOR CHANGES AND STILL BASED ON WPC GUIDANCE. PROGRESSIVE
PATTERN WITH UPPER LEVEL TROF EXITING THIS WEEKEND THEN UL HEIGHTS
BUILD AGAIN WITH A LARGE SFC HIGH PRESSURE MONDAY TO WED. THURSDAY
MORE SHOWERS AS A COLD FRONT AND TROF APPROACH.
PREVIOUS DISCUSSION...
A QUIET PD IS IN STORE FOR THE FCST AREA AFTER THE DEPARTURE OF
THIS WEEKEND`S SYSTEM. LAKE ENHANCED -SHSN DUE TO DEPARTING UPR
LVL TROF WILL TAPER OFF ON SUNDAY...WITH SFC RIDGING AND RAPIDLY
RISING HGTS EARLY NXT WEEK AS ANOTHER DEEP TROF DIGS INTO THE
CNTRL U.S.. THIS SYSTEM WILL BEGIN TO APPROACH THE FCST AREA LATE
IN THE FCST PD. MAXES MODERATING FROM THE U40S ON MONDAY TO THE
MID 50S BY WED.
&&
.AVIATION /13Z THURSDAY THROUGH MONDAY/...
7 AM UPDATE...
SATURATED LOW LEVELS DUE TO SOUTH WINDS AHEAD OF A WARM FRONT HAVE
BROUGHT IFR CONDITIONS TO BGM AND MVFR TO AVP AND ITH. MORE
MOISTURE AND SHOWERS IN WRN NY AND WRN PA WILL MOVE THROUGH
BETWEEN 13 AND 17Z WITH MVFR CONDITIONS AND POSSIBLE IFR
ESPECIALLY AT BGM AND ITH. BY 18Z SOUTH CENT NY AND AVP SHOULD BE
DRY AND IN THE WARM SECTOR. CIGS SHOULD LIFT SOME BUT REMAIN MVFR.
VSBYS WILL RETURN TO VFR. AT SYR AND RME SHOWERS WILL LINGER OFF
AND ON ALL DAY WITH MAINLY MVFR CONDITIONS. THIS EVENING SHOWERS
COME BACK IN EVERYWHERE.
LIGHT SE TO S WINDS WILL INCREASE TO 10 TO 15 WITH HIGHER GUSTS
TODAY AND CONTINUE INTO TONIGHT.
OUTLOOK...
FRI/FRI NGT...MVFR/IFR BECOMING VFR MIDDAY FRIDAY AS RAIN ENDS.
STRONG GUSTY SW TO W WINDS FRI MRNG...ESPECIALLY KSYR-KRME.
SAT/SAT NGT...MVFR IN SHRA/SHSN PRIMARILY CNTRL NY.
SUN...MVFR EARLY CNTRL NY IN -SHRA/-SHSN...IMPRVG TO VFR.
MON...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...HIGH WIND WARNING FROM 2 AM TO 2 PM EDT FRIDAY FOR NYZ009-
015>018-036-037.
&&
$$
SYNOPSIS...PVN
NEAR TERM...PVN/RRM
SHORT TERM...PVN
LONG TERM...TAC
AVIATION...TAC
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
651 AM EDT THU OCT 31 2013
.SYNOPSIS...
A WARM FRONT WILL GENERATE SHOWERS TODAY PRIMARILY THROUGH MID
AFTERNOON. A STRONG COLD FRONT WILL BRING ANOTHER ROUND OF SHOWERS
LATE TONIGHT THROUGH LATE FRIDAY MORNING, ALONG WITH STRONG
GUSTY WINDS. FRIDAY AFTERNOON THROUGH SATURDAY MORNING WILL BE
PRIMARILY DRY, BEFORE SCATTERED SHOWERS IMPACT THE AREA SATURDAY
AFTERNOON.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
330 AM UPDATE...
UL LOW SITTING UP OVR THE DAKOTAS AND EJECTING SLOWLY TO THE EAST.
SIGNIFICANT MOISTURE IS CREEPING UP AHD OF LOW WITH PW VALUES INCRSG
TO 40 MM (1.5 INCHES) OVR THE MID-MS VLY. THIS IS PROGGED TO WORK UP
INTO THE REGION LATE THIS AFTN.
04Z HAND ANALYSIS PLACES WMFNT EXTENDING FM SFC LOW IN IOWA INTO NRN
INDIANA AND OHIO AND SLOWLY HEADING NORTH. DWPTS SOUTH OF THE BNDRY
IN THE MID-ATLANTIC STATES ARE IN THE 50S AND WL WORK UP THIS WAY
THIS AFTN.
AREA OF MODERATE TO HVY RAIN ACRS LWR MICHIGAN DVLPNG IN VICINITY OF
SFC WMFNT ON NOSE OF LLJ. LATEST HRRR RUN BRINGS PCPN INTO WRN ZONES
BY 11Z AND OVRSPRDS MOST OF THE REGION BY AFTN. MAY BE BROKEN ACRS
SRN SXNS THIS AFTN IN THE FORM OF SCTD SHOWERS BASED ON WHAT IS
CURRENTLY GOING ON SOUTH OF SFC WMFNT, THUS WL KEEP JUST SCTD SHOWER
MENTION ALONG AND SOUTH OF THE NRN TIER OF PA.
AFTN MAXES WL TOP OUT IN THE L/M 60S AS 925MB TEMPS CLIMB UP TO ARND
10-12C TDA. THIS IS ALL COURTESY OF WAA THAT WL COMMENCE ACRS THE
REGION AS WMFNT PASSES THRU. CLDY SKIES EXPECTED FOR MOST OF THE DAY
WITH SHOWER ACTIVITY LKLY KEEPING TEMPS FM GETTING OUT OF CONTROL.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
330 AM UPDATE...
PHASING OF S/WVS EXPECTED TONIGHT RESULTING IN DEEPENING SFC LOW
ACRS THE GREAT LKS. H8 LLJ GETS CRANKING BY MIDNIGHT ACRS THE AREA
TO +60KTS THEN ABV 70KTS BY 09Z. BASED ON TRACK OF APPROX 980MB SFC
LOW ACRS SRN ONTARIO BY ALL MODELS, WITH 00Z NAM BEING A TOUCH
FURTHER NORTH, HV DECIDED TO UPGRADE TO HIGH WIND WARNING. BASED ON
LOCAL SYNOPTIC WIND STUDY 6-HR RISE/FALL COUPLET LOOKS TO BE IN THE
BALLPARK FOR HIGH WIND EVENT AND CONFIDENCE IS THERE THAT EXISTING
CNTYS IN WATCH WILL SEE HIGH WINDS AFTER MIDNIGHT TONIGHT. WL ALLOW
DAYSHIFT TO EVALUATE THE NEED FOR WIND ADVISORY ACRS RMNG AREAS TDA.
GIVEN THE STRENGTHENING LLJ AND PHASING OF VORT MAXES TONIGHT EXPECT
OCNL MODERATE SHOWERS LATE WITH QPF AMNTS ACRS THE FAR NORTH IN
VICINITY OF WMFNT APPCHG 1 INCH THRU 12Z FRIDAY. ELSEWHERE EXPECT
ARND 0.50 INCHES.
THO INSTABILITY IS VRY POOR THRU 12Z FRIDAY HV ADDED IN AN ISOLD
THUNDER MENTION AS SHOWALTERS/LI VALUES DIP BLO 0C BTWN 09Z AND 15Z
FRIDAY. CAPES VALUES LOOK TO BE PRETTY PUNY DRG THIS TIME WITH JUST
A COUPLE HUNDRED JOULES, HWVR DYNAMICS ARE EXTREMELY IMPRESSIVE AND
LOW-LVL LR ARE STEEP JUST ALONG AND AHD OF FRONT THUS THINK THAT
THUNDER AT LEAST DESERVES A MENTION, ESPECIALLY CONSIDERING
LIGHTNING STRIKES CURRENTLY OVR LK ERIE.
FROPA LOOKS TO OCCUR SOMETIME FRI MRNG/AFTN WITH HIGH TEMPS ONCE
AGAIN RISING INTO THE 60S ACRS MOST OF THE AREA, THO EXTRM WRN ZONES
MAY TOP OUT ARND 60F. APPEARS THAT THERE WILL BE A SHARP GRADIENT TO
PCPN WITH SHOWERS ENDING IN AREAS WEST OF I-81 AT 18Z AND LINGERING
ACRS ERN ZONES FOR ANOTHER HR OR TWO AFT THIS TIME. CAA WL BE
DELAYED UNTIL THE VRY END OF THE SHORT TERM WITH OVRNGT MINS AND
AFTN MAXES STILL ABV NORMAL FOR SATURDAY.
ANOTHER TROF/ASSOC SFC LOW WL MV INTO AREA FM THE NW BY 12Z
SATURDAY. WINDS WL BCM SRLY AHD OF THIS SFC SYSTEM AND QUICKLY SHIFT
ARND TO THE NW AS LOPRES PASSES ON SATURDAY. THIS WL SET THE STAGE
FOR LK EFFECT SHOWERS ON SAT AFTN AND EVENTUALLY A MIX WITH AND
CHANGE OVR TO SNOW ON SUN MRNG. HV MADE NO CHGS TO THESE GRIDS AT
THIS TIME DUE TO NEAR TERM CHALLENGES.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
2 AM UPDATE...
JUST MINOR CHANGES AND STILL BASED ON WPC GUIDANCE. PROGRESSIVE
PATTERN WITH UPPER LEVEL TROF EXITING THIS WEEKEND THEN UL HEIGHTS
BUILD AGAIN WITH A LARGE SFC HIGH PRESSURE MONDAY TO WED. THURSDAY
MORE SHOWERS AS A COLD FRONT AND TROF APPROACH.
PREVIOUS DISCUSSION...
A QUIET PD IS IN STORE FOR THE FCST AREA AFTER THE DEPARTURE OF
THIS WEEKEND`S SYSTEM. LAKE ENHANCED -SHSN DUE TO DEPARTING UPR
LVL TROF WILL TAPER OFF ON SUNDAY...WITH SFC RIDGING AND RAPIDLY
RISING HGTS EARLY NXT WEEK AS ANOTHER DEEP TROF DIGS INTO THE
CNTRL U.S.. THIS SYSTEM WILL BEGIN TO APPROACH THE FCST AREA LATE
IN THE FCST PD. MAXES MODERATING FROM THE U40S ON MONDAY TO THE
MID 50S BY WED.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
7 AM UPDATE...
SATURATED LOW LEVELS DUE TO SOUTH WINDS AHEAD OF A WARM FRONT HAVE
BROUGHT IFR CONDITIONS TO BGM AND MVFR TO AVP AND ITH. MORE
MOISTURE AND SHOWERS IN WRN NY AND WRN PA WILL MOVE THROUGH
BETWEEN 13 AND 17Z WITH MVFR CONDITIONS AND POSSIBLE IFR
ESPECIALLY AT BGM AND ITH. BY 18Z SOUTH CENT NY AND AVP SHOULD BE
DRY AND IN THE WARM SECTOR. CIGS SHOULD LIFT SOME BUT REMAIN MVFR.
VSBYS WILL RETURN TO VFR. AT SYR AND RME SHOWERS WILL LINGER OFF
AND ON ALL DAY WITH MAINLY MVFR CONDITIONS. THIS EVENING SHOWERS
COME BACK IN EVERYWHERE.
LIGHT SE TO S WINDS WILL INCREASE TO 10 TO 15 WITH HIGHER GUSTS
TODAY AND CONTINUE INTO TONIGHT.
OUTLOOK...
FRI/FRI NGT...MVFR/IFR BECOMING VFR MIDDAY FRIDAY AS RAIN ENDS.
STRONG GUSTY SW TO W WINDS FRI MRNG...ESPECIALLY KSYR-KRME.
SAT/SAT NGT...MVFR IN SHRA/SHSN PRIMARILY CNTRL NY.
SUN...MVFR EARLY CNTRL NY IN -SHRA/-SHSN...IMPRVG TO VFR.
MON...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...HIGH WIND WARNING FROM 2 AM TO 2 PM EDT FRIDAY FOR NYZ009-
015>018-036-037.
&&
$$
SYNOPSIS...PVN
NEAR TERM...PVN
SHORT TERM...PVN
LONG TERM...TAC
AVIATION...TAC
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1000 AM CDT THU OCT 31 2013
.UPDATE...
ISSUED AT 1000 AM CDT THU OCT 31 2013
HAVE LIMITED PATCHY FOG MENTION FOR THE MID TO LATE MORNING TO AREAS
EAST OF THE VALLEY...WHERE SOME VISIBILITIES ARE STILL AROUND 1
SM. THE EDGE OF THE LOWER CLOUD DECK CURRENTLY EXTENDS FROM AROUND
ROSEAU TO GRAFTON TO CARRINGTON. WILL HAVE TO MONITOR THE
PROGRESSION OF THIS DECK THROUGH THE DAY...AND ITS EFFECTS ON HIGH
TEMPS. OTHERWISE...MID/HIGH CLOUDS ARE INCREASING FROM THE
NORTHWEST WITH A WEAK UPPER WAVE. SEEING SOME ECHOES UPSTREAM FROM
THE CANADIAN RADARS. THE HRRR BRINGS SOME WEAKENING ECHOES INTO
THE DVL BASIN EARLY THIS AFTERNOON...BUT WILL NOT ADD ANY POPS FOR
NOW...WITH PERHAPS SOME SPRINKLES. WILL CONTINUE TO MONITOR TRENDS
THIS MORNING.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 313 AM CDT THU OCT 31 2013
WHEN TO END DENSE FOG ADVISORY AND PRECIP CHANCES THROUGHOUT THE
PERIOD WILL BE THE MAIN FORECAST PROBLEMS FOR THE SHORT TERM.
CLEARING LINE HAS MOVED INTO THE WESTERN CWA...ALTHOUGH STILL
PLENTY OF CLOUDS OVER THE VALLEY AND POINTS EASTWARD. VISIBILITIES
HAVE BEEN IMPROVING OVER THE LAST FEW HOURS...AND THINK WITH LIGHT
WEST WINDS STARTING UP WE WILL SEE THAT TREND CONTINUE. ON THE
OTHER HAND...SOME SPOTS ARE STILL DOWN AROUND 1/2 MILE...AND WE
ARE HEADED TOWARDS THE MOST LIKELY TIME PERIOD FOR FOG. WILL HOLD
ONTO THE ADVISORY FOR NOW AND TAKE A SECOND LOOK AT THE 12Z UPDATE.
THE WEST WINDS WILL CONTINUE TO SLOWLY PUSH THE LOW LEVEL MOISTURE
EASTWARD TODAY...ALTHOUGH THE MODELS ALL ARE IN DECENT AGREEMENT
ON KEEPING THE EASTERN COUNTIES SOCKED IN WITH CLOUDS. LOWERED
TEMPS A FEW DEGREES IN THAT AREA INTO THE LOWER 40S...WITH
SLIGHTLY WARMER TEMPS FURTHER WEST WHERE THERE COULD BE SOME
SUNSHINE.
TONIGHT...A DECENT SHORTWAVE TROUGH WILL BE DIGGING DOWN INTO ND
AND BRINGING A FAIR AMOUNT OF MOISTURE WITH IT. CLOUDS WILL
INCREASE AGAIN...AND WITH WEST WINDS BRINGING SOME MIXING...THINK
THAT WILL BE ENOUGH TO KEEP TEMPS IN THE LOW 30S EVEN WITH SOME
COLD AIR ADVECTION. MODELS ALL START BRINGING SOME LIGHT PRECIP
INTO THE WESTERN CWA DURING THE LATE NIGHT HOURS AS THE SHORTWAVE
APPROACHES. ADJUSTED TIMING OF POPS...STARTING THEM IN THE
NORTHWEST BEFORE SUNRISE AND SPREADING EASTWARD DURING THE DAY ON
FRIDAY. FOR NOW KEPT POPS IN THE CHANCE RANGE AS THE SYSTEM MOVES
THROUGH.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 313 AM CDT THU OCT 31 2013
SFC HIGH PRESSURE WILL BUILD IN FRIDAY NIGHT...REDUCING CLOUD
COVER BUT WITH WESTERLY SFC WINDS ADVECTING IN SOME SLIGHTLY
WARMER AIR DID NOT DROP LOWS MUCH...ONLY IN THE UPPER 20S TO LOW
30S. SATURDAY SHOULD BE FAIRLY QUIET AS THE UPPER RIDGE AXIS
BEGINS TO MOVE INTO THE PLAINS. WINDS WILL SHIFT AROUND TO THE
SOUTH AND WITH SOME SUNSHINE HIGHS SHOULD CLIMB INTO THE UPPER
40S. THE SOUTH WINDS WILL CONTINUE TO PICK UP INTO SATURDAY NIGHT
AND MIXING WILL KEEP LOWS IN THE LOW 30S.
SUNDAY THROUGH WEDNESDAY NIGHT...00 UTC GFS/ECMWF IN REASONABLE
AGREEMENT BOTH SHOWING A DEEP PACIFIC TROUGH STALLING ACROSS THE
ROCKIES AND EJECTING SHORT-WAVES ACROSS THE NORTHERN PLAINS. SOME
DIFFERENCES IN MODEL TIMING AND STRENGTH OF THESE WAVES WITH THE
ECMWF MORE PROGRESSIVE AND WEAKER THAN THE GFS. EITHER WAY...THE
BEST CHANCE FOR PRECIPITATION WILL BE SUNDAY NIGHT THROUGH MONDAY
WITH THE MAIN FRONTAL PASSAGE. THERMAL PROFILES ARE GENERALLY WARM
ENOUGH FOR ALL RAIN WITH THE THREAT FOR A RAIN/SNOW MIX AT NIGHT.
TUESDAY/WEDNESDAY LOOK MOSTLY DRY AT THIS TIME. EXPECT CONSIDERABLE
CLOUDINESS THROUGH THE PERIOD WITH A SLIGHT COOLING TREND TUESDAY
AND WEDNESDAY IN THE WAKE OF THE COLD FRONT. DAYTIME HIGHS IN THE
MID TO UPPER 40S SUNDAY WILL FALL INTO THE UPPER 30S TO LOWER 40S
BY MID-WEEK. NIGHTTIME LOWS WILL RANGE FROM THE MID 20S TO MID
30S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 1000 AM CDT THU OCT 31 2013
LINGERING LIFR CLOUDS AND PATCHY FOG OVER NORTHWEST AND WEST CENTRAL
MN WILL SLOWLY ERODE AND SHIFT EASTWARD THROUGH THE FORENOON...WITH
IFR /MVFR/ CIGS EXPECTED TO PERSIST INTO NCNTRL AND NTRL MN THROUGH
TEH REMAINDER OF THE DAY. PARTIALLY CLEARING SKIES ACROSS EASTERN ND
INTO THE RRV WILL SEE AN INCREASING HIDG CLOUD DECK THROUGH MIDDAY
AND INTO TEH AFTERNOON... WITH LIGHT WESTERLY WINDS SHIFTING TO THE
NORTHWEST THROUGH THE AFTERNOON AS WELL.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...MAKOWSKI
SHORT TERM...JR
LONG TERM...JR/ROGERS
AVIATION...GUST
AREA FORECAST DISCUSSION...UPDATED
NWS CHARLESTON WV
ISSUED BY NATIONAL WEATHER SERVICE PITTSBURGH PA
1146 AM EDT THU OCT 31 2013
.SYNOPSIS...
WARM SOUTHERLY WINDS TODAY. COLD FRONT TONIGHT WITH GUSTY SHOWERS.
COOLER FOR THE WEEKEND...WITH A REINFORCING FRONT SATURDAY. HIGH
PRESSURE LATE IN THE WEEKEND AND EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH FRIDAY/...
SOME ADJUSTMENTS WERE MADE TO NEAR-TERM POPS TO REFLECT CURRENT
LGT RAIN SHWRS IN FCST AREA. WITH CLD CVR BCMG MORE SOLID...TEMPS
WILL STRUGGLE TO INCR MUCH ABV LWR 70S. AS PREVLY THOUGHT...MAIN
MDT-HVY RAIN WILL BE WITH BAND OF SHWRS ALONG CDFNT. PRIOR TO THE
ARRIVAL OF THE BNDRY...OCNL SHWRS XPCD. POPS WERE INCRD DURG THIS
PD AND OCNL WORDING WAS INCLUDED THRU 0600 UTC...AFTER WHICH
WDSPRD WORDING WAS USED TO REFLECT MORE CONSISTENT CVRG OF PCPN.
SHWRS WILL VACATE FRI MRNG...WITH FOCUS FOR POPS MAINLY IN ERN
ZONES AND ALONG TYPICAL UPSLP-FOCUSED AREAS.
WIND ADZY RMNS IN EFFECT TNGT FOR THE HIGHER ELEVATIONS. VERY
STRONG H9/H8 FLOW STILL XPCD TO PRODUCE GUSTS UP TO 50 MPH OVNGT.
IN THE WAKE OF THE CDFNT...MOIST AMS WILL RMN IN PLACE AS LAPSE
RATES ABV THE SFC STEEPEN CONSIDERABLY. THUS...WDSPRD CLD CVR
LKLY IN THE FORM OF STRATOCU SHOULD CONT ON FRI.
PREVIOUS DISCUSSION BELOW...
NOT MUCH CHANGE IN PREV FCST THINKING REGARDING MUCH ADVERTISED SYS
TO AFFECT THE AREA THIS HALLOWEEN NIGHT. THERE IS SOME CONCERN FOR
SOME -SHRA TO MOVE THRU BY EARLY AFTN AS RUC AND ESPECIALLY HRRR
SHOWS SOME MID LVL FORCING IN WAA MOVING ACROSS. DIDNT GET TOO
CARRIED AWAY WITH THIS GIVEN STRONG DOWNSLOPING FLOW AMID DRY LLVLS
BUT ALLOWED FOR CHC POPS W OF THE MTNS WITH SOME LKLY FOR SE OH. MAY
END UP INCREASING POPS MORE W LOWLANDS/NE KY AND ESPECIALLY SE OH
FOR THIS AFTN SHOULD THESE TRENDS IN MDLS CONT.
THE MAIN SHOW STILL LOOKS TO BE WITH PREFRONTAL BAND THIS EVE AND
THEN FRONTAL ACTION. IT IS LOOKING LIKE TRICK OR TREATERS WILL GET
WET IN SE OH AND NE KY...PERHAPS EVEN W LOWLANDS. NOT SURE HOW
STRONG PREFRONTAL BAND IS ONCE INTO AREA THIS EVE GIVEN LACK OF
INSTABILITY...BUT SE OH STANDS BEST SHOT OF SEEING LOW TOPPED QLCS
BEFORE PROBABLY WEAKENING AS IT PUSHES E. ACTUAL COLD FRONT LOOKS TO
ENTER SE OH ARND 06Z...CROSSING OH RVR BY 09Z...AND EXITING MTNS
ARND 12Z. EXPECT A DECENT FRONTAL BAND WITH BAROCLINIC ZONE. DESPITE
LACK OF ANY INSTABILITY...LEFT SOME LOW THUNDER CHC IN...GIVING A
NOD TO STRONG LLJ AND UPR TROF TRYING TO GO NEG TILT.
THIS ALL LEADS TO THE WIND CONCERN. SPC CONT TO KEEP SVR SLIGHT RISK
W OF AREA. STILL...THERE IS CONCERN FOR CONVECTIVE TYPE FRONTAL SHRA
TO BRING DOWN SOME OF THAT 70 KT LLJ TO SFC. AFTER SOME COORDINATION
WITH SOME OF THE SURROUNDING OFFICES FELT PRUDENT TO HANDLE THIS
WITH A WIND ADV FOR ALL OF THE MOUNTAINOUS CO INCLUDING SW VA GIVEN
THESE ARE SYNOPTIC WINDS. HELD OFF ON ANYTHING OUTSIDE OF THE MTNS
AS NOT AS CONFIDENT ON SEEING CRITERIA GUSTS EVEN WITH ANY STOUT
FRONTAL SHRA. STILL EXPECT SOME 35 TO 40 MPH GUSTS THOUGH. NOT
EXPECTING THE STRONG GUSTS DURING THE DAYLIGHT HRS...UNLESS THIS SYS
SPEEDS UP. HARD TO GET STRONG GUSTS ON WAA WITHOUT SOME HELP FROM
CONVECTIVE SHRA...ESPECIALLY WITH WHAT WILL PROBABLY BE AN OVC SKY
OF MID AND HI CLDS.
FOR TEMPS...ELECTED TO GO CLOSER TO COOLER SIDE OF GUIDANCE TDY WITH
ALL THE CLDS AND MAYBE SOME SHRA IN AFTN W ZONES. STILL HAVE UPR 60S
TO LWR 70S FOR MUCH OF THE AREA ON STRONG DOWNSLOPE FLOW AND WAA.
TONIGHTS NUMBERS LOOKED GOOD FROM PREV FCST AND ONLY NEEDED SOME
TWEAKING TO ACCOUNT FOR FALLING TEMPS LATE IN SE OH/NE KY POST
FRONTAL AND IMPROVING SKY.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY/...
A STRONG TROUGH MOVES THROUGH ON SATURDAY...PROVIDING A
REINFORCING COLD FRONT. MODELS ARE DIVIDED ON TIMING OF
PRECIPITATION AND HOW MUCH. WILL STAY NEAR CURRENT FORECAST FOR
NOW...AS THIS APPEARS TO BE A GOOD MIDDLE GROUND.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
COLD SYSTEM EXITING THE AREA AT THE START OF THE PERIOD...WARM
SYSTEM MOVING IN AT THE END...WITH HIGH PRESSURE LARGE AND IN CHARGE
IN BETWEEN.
PERIOD BEGINS WITH LOW LEVEL COLD ADVECTION IN W TO NW FLOW BENEATH
UPPER LEVEL SHORT WAVE/ LONG WAVE TROUGH RIGHT OVER THE AREA. HAVE
UPSLOPE SNOW SHOWERS TAPERING OFF OVERNIGHT INTO FIRST THING SUN
MORNING...BUT WITH A SWITCH TO SNOW SHOWERS EARLY ON OVER THE HIGH
TERRAIN...THE SNOW LEVELS LOWERING AS THE PRECIPITATION WINDS DOWN.
AS THE CLOUD TOPS LOWER AND WE LOSE CRYSTAL GROWTH...PRECIPITATION
MAY END BEFORE A SWITCH OVER AT LOCATIONS LIKE EKN AND BKW.
AFTER THE COLD START...THE WEATHER WARMS UP EARLY NEXT WEAK AS THE
L/W TROUGH POSITION SHIFTS QUICKLY E...AND A L/W RIDGE AXIS BECOMES
ESTABLISHED ALONG THE E COAST BY THE END OF THE PERIOD. LARGE SFC
HIGH PASSES N OF THE AREA EARLY MON BUT SFC RIDGING DOWN THE E SIDE
OF THE APPALACHIANS PERSISTS INTO WED. LOW LEVEL MOISTURE IN THE
LONG ATLANTIC FETCH S OF THE LARGE HIGH WILL LIKELY INTRODUCE CLOUDS
TO THE EASTERN SLOPES BY TUE. MEANWHILE...LONG FETCH UPPER LEVEL SW
FLOW FROM NORTHERN MEXICO SHOULD CARRY MID AND HIGH CLOUD INTO THE
AREA BEGINNING TUE AS WELL.
HAVE THE CHANCE FOR RAIN SHOWERS STARTING WED...AT FIRST ALONG THE
EASTERN SLOPES AND IN THE W WITH THE TYPICAL S FLOW SHADOW ACROSS
THE MIDDLE OF THE CWA THAT THEN GRADUALLY FILLS IN WED NT. WITH WPC
BEING SLOWER WITH THE FRONT THAN EVEN THE SLOWER ECMWF...KEPT THE
FRONT W OF THE AREA THROUGH THE END OF THE PERIOD...12Z THU...THE
GFS HAS THE FRONT ABOUT HALF THE WAY THROUGH THE CWA AT THAT TIME.
THE 12Z ECMWF ADDED A NEW TWIST...WITH A MUCH STRONGER UPPER LEVEL
HIGH OVER THE SERN STATES KEEPING THE FRONT FROM REACHING ALL BUT
PERHAPS NORTHERN PORTIONS OF THE AREA ALMOST ALL THE WAY THROUGH ITS
240 HR RUN.
USED MOSTLY AN ECE/WPC BLEND FOR TEMPERATURES WITH THE MEX ALSO
BLENDED IN FOR LOWS EARLY ON. LEANED TOWARD HIGHER GUIDANCE LATE IN
THE PERIOD IN THE MILD STRONG S FLOW AHEAD OF THE FRONT OUT TO THE W.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
12Z THURSDAY THRU 12Z FRIDAY...
MAINLY VFR CONDITIONS THROUGH EARLY AFTN WITH A BKN TO OVC DECK OF
MID/HI CLDS AND SOME VERY LIGHT SHRA FROM TIME TO TIME ALONG AND W
OF OH RVR. CIGS LWR LATE THIS AFTN AND INTO THIS EVE AS PREFRONTAL
SHRA WORK IN FROM W. MVFR CIGS WILL OVERSPREAD SE OH AFTER 21Z AND
TAKING UNTIL PERHAPS 06Z ELSEWHERE...GIVEN STRONG LLVL DOWNSLOPING
FLOW. SFC FRONT TO MAKE INROADS INTO SE OH BY 06Z...CROSSING OH
RVR BY 09Z...AND EXITING MTNS ARND 12Z. SOME IFR CIGS/VSBY
POSSIBLE WITH PREFRONTAL BAND AND ACTUAL FRONTAL BAND. S TO SW
FLOW ALOFT WILL BE INCREASING TDY WHICH MAY LEAD TO A FEW HRS OF
LLWS CONCERNS FOR LOWLAND TAF SITES. HELD OFF IN THE 06Z ISSUANCE
AND WILL REEVALUATE FOR THE 09Z AMENDMENT. WITH EXPECTED OVC SKY
TDY AND WAA NATURE TO FLOW...THINK WIND GUSTS WILL BE HELD IN
CHECK ACROSS THE TERMINALS...GENERALLY LESS THAN 20 KTS DESPITE
APPROACHING LLJ. DID INCREASE THE GUSTS TONIGHT TO NEAR 30 KTS.
MTN SITES COULD GUST HIGHER BY 06Z BUT DID NOT WANT TO GET TOO
CARRIED AWAY AT THIS DISTANCE AS IT WILL PROBABLY TAKE STOUT
CONVECTIVE SHRA TO BRING DOWN THE STRONGER WINDS. HAVE OH RVR
SITES LOSING POST FRONTAL STRATUS BY 12Z WITH A DRYING COLUMN.
ALSO LET GUSTS SUBSIDE AFTER FROPA.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATIVE SCENARIOS: WINDS MAY NOT BE AS GUSTY TDY. TIMING OF SHRA
MAY VARY HEADING INTO LATE THIS AFTN AND EARLY EVE.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
AFTER 18Z FRIDAY...
IFR POSSIBLE IN THE HIGHER ELEVATIONS OF THE MOUNTAINS SATURDAY
NIGHT INTO EARLY SUNDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...WIND ADVISORY FROM 6 PM THIS EVENING TO 7 AM EDT FRIDAY FOR
WVZ033>038-046-047.
OH...NONE.
KY...NONE.
VA...WIND ADVISORY FROM 6 PM THIS EVENING TO 7 AM EDT FRIDAY FOR
VAZ003-004.
&&
$$
SYNOPSIS...TRM/RPY/30
NEAR TERM...KRAMAR/WFO PBZ
SHORT TERM...RPY
LONG TERM...TRM
AVIATION...SL
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
646 AM EDT THU OCT 31 2013
.SYNOPSIS...
WARM SOUTHERLY WINDS TODAY. COLD FRONT TONIGHT WITH GUSTY SHOWERS.
COOLER FOR THE WEEKEND...WITH A REINFORCING FRONT SATURDAY. HIGH
PRESSURE LATE IN THE WEEKEND AND EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
630 AM UPDATE...
A FEW VERY LIGHT SHRA MOVING THRU THE AREA...FALLING OUT OF A MID
DECK. LOOKING MORE AND MORE LIKE THIS WILL BE THE RULE TODAY
ACROSS W LOWLANDS AND ESPECIALLY NE KY/SE OH. ELECTED TO SPEED UP
BRINGING IN THE HIGHER POPS ACROSS THOSE AREAS FOR THIS AFTN.
STILL EXPECT THE SHRA TO VERY LIGHT IN NATURE.
PREVIOUS DISCUSSION BELOW...
NOT MUCH CHANGE IN PREV FCST THINKING REGARDING MUCH ADVERTISED SYS
TO AFFECT THE AREA THIS HALLOWEEN NIGHT. THERE IS SOME CONCERN FOR
SOME -SHRA TO MOVE THRU BY EARLY AFTN AS RUC AND ESPECIALLY HRRR
SHOWS SOME MID LVL FORCING IN WAA MOVING ACROSS. DIDNT GET TOO
CARRIED AWAY WITH THIS GIVEN STRONG DOWNSLOPING FLOW AMID DRY LLVLS
BUT ALLOWED FOR CHC POPS W OF THE MTNS WITH SOME LKLY FOR SE OH. MAY
END UP INCREASING POPS MORE W LOWLANDS/NE KY AND ESPECIALLY SE OH
FOR THIS AFTN SHOULD THESE TRENDS IN MDLS CONT.
THE MAIN SHOW STILL LOOKS TO BE WITH PREFRONTAL BAND THIS EVE AND
THEN FRONTAL ACTION. IT IS LOOKING LIKE TRICK OR TREATERS WILL GET
WET IN SE OH AND NE KY...PERHAPS EVEN W LOWLANDS. NOT SURE HOW
STRONG PREFRONTAL BAND IS ONCE INTO AREA THIS EVE GIVEN LACK OF
INSTABILITY...BUT SE OH STANDS BEST SHOT OF SEEING LOW TOPPED QLCS
BEFORE PROBABLY WEAKENING AS IT PUSHES E. ACTUAL COLD FRONT LOOKS TO
ENTER SE OH ARND 06Z...CROSSING OH RVR BY 09Z...AND EXITING MTNS
ARND 12Z. EXPECT A DECENT FRONTAL BAND WITH BAROCLINIC ZONE. DESPITE
LACK OF ANY INSTABILITY...LEFT SOME LOW THUNDER CHC IN...GIVING A
NOD TO STRONG LLJ AND UPR TROF TRYING TO GO NEG TILT.
THIS ALL LEADS TO THE WIND CONCERN. SPC CONT TO KEEP SVR SLIGHT RISK
W OF AREA. STILL...THERE IS CONCERN FOR CONVECTIVE TYPE FRONTAL SHRA
TO BRING DOWN SOME OF THAT 70 KT LLJ TO SFC. AFTER SOME COORDINATION
WITH SOME OF THE SURROUNDING OFFICES FELT PRUDENT TO HANDLE THIS
WITH A WIND ADV FOR ALL OF THE MOUNTAINOUS CO INCLUDING SW VA GIVEN
THESE ARE SYNOPTIC WINDS. HELD OFF ON ANYTHING OUTSIDE OF THE MTNS
AS NOT AS CONFIDENT ON SEEING CRITERIA GUSTS EVEN WITH ANY STOUT
FRONTAL SHRA. STILL EXPECT SOME 35 TO 40 MPH GUSTS THOUGH. NOT
EXPECTING THE STRONG GUSTS DURING THE DAYLIGHT HRS...UNLESS THIS SYS
SPEEDS UP. HARD TO GET STRONG GUSTS ON WAA WITHOUT SOME HELP FROM
CONVECTIVE SHRA...ESPECIALLY WITH WHAT WILL PROBABLY BE AN OVC SKY
OF MID AND HI CLDS.
FOR TEMPS...ELECTED TO GO CLOSER TO COOLER SIDE OF GUIDANCE TDY WITH
ALL THE CLDS AND MAYBE SOME SHRA IN AFTN W ZONES. STILL HAVE UPR 60S
TO LWR 70S FOR MUCH OF THE AREA ON STRONG DOWNSLOPE FLOW AND WAA.
TONIGHTS NUMBERS LOOKED GOOD FROM PREV FCST AND ONLY NEEDED SOME
TWEAKING TO ACCOUNT FOR FALLING TEMPS LATE IN SE OH/NE KY POST
FRONTAL AND IMPROVING SKY.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
MOST MODELS SHOWING DEEPER MOISTURE FROM THE COLD FRONT MOVING AWAY
QUICKLY FRIDAY MORNING. NAM IS AN OUTLIER HERE...AS IT DEVELOPS A
WAVE ALONG THE FRONT AND SKIRTS THE EASTERN COUNTIES. THE
ECMWF...GFS...AND CANADIAN ARE ALL SHOWING THE WAVE MUCH FURTHER
EAST. WILL DISCOUNT THE HANDLING OF THIS WAVE BY THE NAM.
MOS HIGHS ON FRIDAY ARE STILL LOOKING WAY TOO WARM BASED ON 850 MB
TEMPERATURES AND BEING BEHIND THE COLD FRONT. WILL CONTINUE TO
UNDERCUT CONSIDERABLY.
A STRONG TROUGH MOVES THROUGH ON SATURDAY...PROVIDING A REINFORCING
COLD FRONT. MODELS ARE DIVIDED ON TIMING OF PRECIPITATION AND HOW
MUCH. WILL STAY NEAR CURRENT FORECAST FOR NOW...AS THIS APPEARS TO
BE A GOOD MIDDLE GROUND.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
COLD SYSTEM EXITING THE AREA AT THE START OF THE PERIOD...WARM
SYSTEM MOVING IN AT THE END...WITH HIGH PRESSURE LARGE AND IN CHARGE
IN BETWEEN.
PERIOD BEGINS WITH LOW LEVEL COLD ADVECTION IN W TO NW FLOW BENEATH
UPPER LEVEL SHORT WAVE/ LONG WAVE TROUGH RIGHT OVER THE AREA. HAVE
UPSLOPE SNOW SHOWERS TAPERING OFF OVERNIGHT INTO FIRST THING SUN
MORNING...BUT WITH A SWITCH TO SNOW SHOWERS EARLY ON OVER THE HIGH
TERRAIN...THE SNOW LEVELS LOWERING AS THE PRECIPITATION WINDS DOWN.
AS THE CLOUD TOPS LOWER AND WE LOSE CRYSTAL GROWTH...PRECIPITATION
MAY END BEFORE A SWITCH OVER AT LOCATIONS LIKE EKN AND BKW.
AFTER THE COLD START...THE WEATHER WARMS UP EARLY NEXT WEAK AS THE
L/W TROUGH POSITION SHIFTS QUICKLY E...AND A L/W RIDGE AXIS BECOMES
ESTABLISHED ALONG THE E COAST BY THE END OF THE PERIOD. LARGE SFC
HIGH PASSES N OF THE AREA EARLY MON BUT SFC RIDGING DOWN THE E SIDE
OF THE APPALACHIANS PERSISTS INTO WED. LOW LEVEL MOISTURE IN THE
LONG ATLANTIC FETCH S OF THE LARGE HIGH WILL LIKELY INTRODUCE CLOUDS
TO THE EASTERN SLOPES BY TUE. MEANWHILE...LONG FETCH UPPER LEVEL SW
FLOW FROM NORTHERN MEXICO SHOULD CARRY MID AND HIGH CLOUD INTO THE
AREA BEGINNING TUE AS WELL.
HAVE THE CHANCE FOR RAIN SHOWERS STARTING WED...AT FIRST ALONG THE
EASTERN SLOPES AND IN THE W WITH THE TYPICAL S FLOW SHADOW ACROSS
THE MIDDLE OF THE CWA THAT THEN GRADUALLY FILLS IN WED NT. WITH WPC
BEING SLOWER WITH THE FRONT THAN EVEN THE SLOWER ECMWF...KEPT THE
FRONT W OF THE AREA THROUGH THE END OF THE PERIOD...12Z THU...THE
GFS HAS THE FRONT ABOUT HALF THE WAY THROUGH THE CWA AT THAT TIME.
THE 12Z ECMWF ADDED A NEW TWIST...WITH A MUCH STRONGER UPPER LEVEL
HIGH OVER THE SERN STATES KEEPING THE FRONT FROM REACHING ALL BUT
PERHAPS NORTHERN PORTIONS OF THE AREA ALMOST ALL THE WAY THROUGH ITS
240 HR RUN.
USED MOSTLY AN ECE/WPC BLEND FOR TEMPERATURES WITH THE MEX ALSO
BLENDED IN FOR LOWS EARLY ON. LEANED TOWARD HIGHER GUIDANCE LATE IN
THE PERIOD IN THE MILD STRONG S FLOW AHEAD OF THE FRONT OUT TO THE W.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
12Z THURSDAY THRU 12Z FRIDAY...
MAINLY VFR CONDITIONS THROUGH EARLY AFTN WITH A BKN TO OVC DECK OF
MID/HI CLDS AND SOME VERY LIGHT SHRA FROM TIME TO TIME ALONG AND W
OF OH RVR. CIGS LWR LATE THIS AFTN AND INTO THIS EVE AS PREFRONTAL
SHRA WORK IN FROM W. MVFR CIGS WILL OVERSPREAD SE OH AFTER 21Z AND
TAKING UNTIL PERHAPS 06Z ELSEWHERE...GIVEN STRONG LLVL DOWNSLOPING
FLOW. SFC FRONT TO MAKE INROADS INTO SE OH BY 06Z...CROSSING OH
RVR BY 09Z...AND EXITING MTNS ARND 12Z. SOME IFR CIGS/VSBY
POSSIBLE WITH PREFRONTAL BAND AND ACTUAL FRONTAL BAND. S TO SW
FLOW ALOFT WILL BE INCREASING TDY WHICH MAY LEAD TO A FEW HRS OF
LLWS CONCERNS FOR LOWLAND TAF SITES. HELD OFF IN THE 06Z ISSUANCE
AND WILL REEVALUATE FOR THE 09Z AMENDMENT. WITH EXPECTED OVC SKY
TDY AND WAA NATURE TO FLOW...THINK WIND GUSTS WILL BE HELD IN
CHECK ACROSS THE TERMINALS...GENERALLY LESS THAN 20 KTS DESPITE
APPROACHING LLJ. DID INCREASE THE GUSTS TONIGHT TO NEAR 30 KTS.
MTN SITES COULD GUST HIGHER BY 06Z BUT DID NOT WANT TO GET TOO
CARRIED AWAY AT THIS DISTANCE AS IT WILL PROBABLY TAKE STOUT
CONVECTIVE SHRA TO BRING DOWN THE STRONGER WINDS. HAVE OH RVR
SITES LOSING POST FRONTAL STRATUS BY 12Z WITH A DRYING COLUMN.
ALSO LET GUSTS SUBSIDE AFTER FROPA.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATIVE SCENARIOS: WINDS MAY NOT BE AS GUSTY TDY. TIMING OF SHRA
MAY VARY HEADING INTO LATE THIS AFTN AND EARLY EVE.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22
EDT 1HRLY 07 08 09 10 11 12 13 14 15 16 17 18
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY L L M H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z FRIDAY...
IFR POSSIBLE IN THE HIGHER ELEVATIONS OF THE MOUNTAINS SATURDAY
NIGHT INTO EARLY SUNDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...WIND ADVISORY FROM 6 PM THIS EVENING TO 7 AM EDT FRIDAY FOR
WVZ033>038-046-047.
OH...NONE.
KY...NONE.
VA...WIND ADVISORY FROM 6 PM THIS EVENING TO 7 AM EDT FRIDAY FOR
VAZ003-004.
&&
$$
SYNOPSIS...TRM/RPY/30
NEAR TERM...30
SHORT TERM...RPY
LONG TERM...TRM
AVIATION...SL
AREA FORECAST DISCUSSION
NWS MEDFORD OR
836 AM PDT THU OCT 31 2013
.DISCUSSION...A WEAK FRONTAL BOUNDARY WILL MOVE OVER THE NORTHERN
PART OF THE FORECAST AREA TODAY. AT THE SAME TIME 500MB HEIGHTS
ARE INCREASING AND SHOULD KEEP MOST IF NOT ALL PRECIPITATION NORTH
OF OUR AREA. THE LATEST RAP MODEL GUIDANCE SHOWS VERY LIGHT QPF
AMOUNTS OVER COOS COUNTY THIS MORNING, THEN NOTHING IN THE
AFTERNOON. THUS HAVE SCALED BACK POPS FOR THIS MORNING AND
AFTERNOON AND KEPT THEM MAINLY CONFINED TO COOS COUNTY, NORTHERN
DOUGLAS AND FROM AROUND CRATER LAKE NORTH. ELSEWHERE DRY AND MILD
CONDITIONS ARE EXPECTED WITH CLOUD COVER GRADUALLY DECREASING FROM
SOUTH TO NORTH AND MILDER TEMPERATURES. THE NEXT FOCUS OF CONCERN
WILL BE SATURDAY WITH THE ARRIVAL OF A STRONGER COLD FRONT. A
PRELIMINARY LOOK AT SOME OF THE GUIDANCE SHOWS THERE IS SOME
UNCERTAINTY REGARDING THE STRENGTH OF THE SURFACE LOW. -PETRUCELLI
&&
.AVIATION...BASED ON THE 31/12Z TAF CYCLE.
A FRONTAL BOUNDARY WILL WEAKEN OVER THE AREA TODAY WITH VFR EAST OF
THE CASCADES. EXPECT MOSTLY VFR CIGS ALONG AND WEST OF THE CASCADES,
BUT LOCAL MVFR CIGS CAN OCCUR ALONG THE COAST AND INTO THE UMPQUA
BASIN WITH SOME HIGHER TERRAIN OBSCURATION. CIGS WILL LOWER TO IFR
OVERNIGHT INTO FRIDAY MORNING ALONG THE COAST AND IN THE UMPQUA
VALLEY ALONG WITH SOME VIS REDUCTIONS DUE TO FOG. THE REMAINDER OF
THE AREA SHOULD BE VFR, THOUGH FOG PATCHES MAY DEVELOP TOWARD
SUNRISE IN SOME OF THE DEEPER VALLEYS AND BASINS. SPILDE
&&
.PREV DISCUSSION... /ISSUED 235 AM PDT THU OCT 31 2013/
DISCUSSION...THE TRAILING END OF A WEAK COLD FRONT WILL BRUSH THE
NORTHERN PORTIONS OF THE FORECAST AREA TODAY. HOWEVER...THE JET
AXIS IS WELL NORTH OF THE AREA...OVER VANCOUVER BC AND THE PRECIP
ASSOCIATED WITH THIS FRONT WILL BE LIGHT. THE UPPER LEVEL RIDGE
WILL ASSERT ITSELF POST THE BACK DOOR SLIDER...WITH A THERMAL
TROUGH DEEPENING AT THE COAST AND OFFSHORE FLOW EXTENDING FROM THE
COAST TO THE CASCADES. THE UPPER LEVEL TROUGH MIGRATES EAST WITH
AN UPPER LEVEL TROUGH DEEPENING AHEAD OF THE NEXT...MUCH STRONGER
FRONT THAT MOVES INTO THE COASTAL WATERS FRIDAY NIGHT. THIS FRONT
MOVES IN THROUGH THE REGION ON THE RIGHT ENTRANCE REGION OF A 100
KT JET. IN SPITE OF THE GOOD JET DYNAMICS THE PRECEDENT MOISTURE
FLOW IS WEAK AND THIS SYSTEM SHOULD NOT BE A MAJOR PRECIP
PRODUCER. THE NORTHWEST FLOW BEHIND THIS SYSTEM IS STRONG...AND
THE TRACK OF THE SURFACE LOW WILL BRING SEAS UP QUICKLY AND USHER
A COLD AIR MASS BEHIND IT. 850 MB TEMPS OF -2C MOVE IN SATURDAY
NIGHT...LOWERING SNOW LEVELS TO THE CASCADE PASSES AND HIGHER
PASSES IN I-5 ON THE TAIL END OF THE SYSTEM. ANOTHER FRONT MOVES
IN QUICKLY BEHIND IT ON THE LEFT EXIT REGION OF A DESCENDING FRONT
SUNDAY. THE COLDER AIR MASS SHOULD STILL BE IN PLACE OVER THE
REGION AS THIS QUICK MOVING SYSTEM BRINGS A QUICK ROUND OF HEAVIER
SNOW TO THE HIGHER PASSES.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...NONE.
$$
AREA FORECAST DISCUSSION
NWS PORTLAND OR
318 AM PDT THU OCT 31 2013
.SYNOPSIS...A WEAK WARM FRONT IS BRINGING LIGHT RAIN AND DRIZZLE TO
THE REGION THIS MORNING. A WEAKENING SURFACE TROUGH WILL BRING MORE
SHOWERS LATER THIS MORNING AND THIS AFTERNOON. HIGH PRESSURE WILL
BRING DRIER WEATHER TO THE REGION FRIDAY. A STRONGER STORM SYSTEM
SATURDAY WILL BRING BREEZY CONDITIONS ALONG THE COAST...VALLEY RAIN
AND MOUNTAIN SNOW. RELATIVELY MORE QUIET WEATHER SHOULD RETURN LATE
IN THE WEEKEND INTO EARLY NEXT BEFORE ANOTHER SERIES OF EVEN COLDER
STORM SYSTEMS POSSIBLY IMPACT THE REGION DURING THE MIDDLE TO LATTER
PART OF NEXT WEEK.
&&
.SHORT TERM...
A LOOK AT DOPPLER RADAR IMAGERY THIS MORNING SHOWS RADAR ECHOES
SPREADING ONTO THE S WA COAST AHEAD OF AN APPROACHING FRONTAL SYSTEM.
THIS PRECIPITATION IS DUE TO A WEAK WARM FRONT AND ASSOCIATED
ISENTROPIC LIFT. THE FCST MODELS ARE HANDLING THIS FAIRLY WELL...AND
INDICATE THAT LIGHT RAIN OR DRIZZLE WILL SPREAD FURTHER DOWN THE
COAST DURING THE EARLY MORNING HOURS...THEN PUSH INLAND AFTER 12Z.
THE ISENTROPIC LIFT APPEARS TO DIMINISH SIGNIFICANT BY 18Z.
HOWEVER...LIGHT RAIN OR SHOWERS SHOULD CONTINUE DURING THE AFTERNOON
AS A WEAK SURFACE TROUGH AND RESULTANT CONVERGENCE PROVIDE SOME
ADDITIONAL LIFT. BY LATE AFTERNOON INTO THIS EVENING...THE BEST
SHOWER COVERAGE SHOULD MAINLY BE CONFINED TO THE HIGHER TERRAIN OF
THE MOUNTAINS AS WEAK OROGRAPHICS PROVIDE A BIT OF ADDITIONAL
FORCING.
A FEW SHOWERS MAY LINGER IN THE CASCADES OVERNIGHT..BUT THE TREND
WILL BE TOWARD DRIER WEATHER FOR FRI. UPPER LEVEL RIDGING REMAINING
IN PLACE OVER THE NE PAC COMBINED WITH THE ADDITIONAL LOW LEVEL
MOISTURE FROM TODAY/S SHOWERS SHOULD CREATE FAVORABLE CONDITIONS FOR
SOME SHALLOW STRATUS OR PATCHY FOG FORMATION EARLY FRI MORNING FOR
THE INTERIOR LOWLANDS AND ALONG THE COAST. OTHERWISE...EXPECT A
RELATIVELY QUIET DAY ON FRI. MOST LOCATIONS SHOULD REMAIN DRY AND
THERE WILL LIKELY BE SOME SUNSHINE AS WELL...PARTICULARLY FOR
SOUTHERN PORTIONS OF THE FCST AREA. LATE IN THE DAY...CLOUDS WILL
BEGIN TO SPREAD IN FROM THE NW AHEAD OF THE NEXT APPROACHING SYSTEM.
THIS NEXT SYSTEM WILL PACK SIGNIFICANTLY MORE PUNCH...BRINGING GUSTY
WINDS ALONG THE COAST...A DECENT SHOT OF RAIN...AND ACCUMULATING
MOUNTAIN SNOW. THIS WILL BE A FAST MOVING SYSTEM...AND THE EXACT
TRACK OF THE SURFACE LOW WILL BE A BIT DIFFICULT TO PIN DOWN UNTIL WE
GET CLOSER TO THE EVENT. THE UPPER LEVEL FORCING WILL BE PROVIDED BY
TWO UPPER LEVEL SHORTWAVES THAT ARE PROGGED TO PHASE OVER THE NE PAC
ON FRI AND WILL PUSH INTO THE PAC NW OVERNIGHT FRI INTO SAT AS A
FAIRLY SHARP UPPER LEVEL TROUGH.
EXPECT RAIN TO BEGIN SPREADING INTO THE NORTHERN COASTAL ZONES FRI
EVENING...THEN PUSH RAPIDLY INLAND OVERNIGHT. THE FCST MODELS
CONTINUE TO INDICATE VERY LITTLE IN THE WAY OF PRE FRONTAL WINDS. BUT
POST FRONTAL NW WINDS WILL LIKELY BRING BREEZY TO GUSTY CONDITIONS TO
THE COASTAL WATERS AND POSSIBLY THE COAST ON SAT MORNING. THE TREND
HAS BEEN TOWARD WEAKENING THESE POST FRONTAL WINDS A BIT. MUCH STILL
DEPENDS ON THE EXACT TRACK OF THE LOW...BUT THINK THAT THERE IS
POTENTIAL TO SEE WIND GUSTS OF 35 TO 45 MPH OVER THE COASTAL WATERS
AND POSSIBLY ALONG THE COAST AS WELL.
SNOW LEVELS WILL REMAIN HIGH AT THE ONSET OF THIS EVENT...WITH RAIN
FALLING FOR ALL BUT THE HIGHEST CASCADE PEAKS OVERNIGHT FRI INTO
EARLY SAT MORNING. HOWEVER THE AIRMASS WILL COOL RAPIDLY AS THE UPPER
LEVEL COLD POOL MOVES ALOFT BETWEEN 12Z AND 18Z SAT. BY LATE MORNING
OR EARLY AFTERNOON...EXPECT THE SNOW LEVEL TO BE DOWN TO THE HIGHER
CASCADE PASSES...THEN DROP DOWN TO THE 2500 TO 3000 FT LEVEL BY SAT
EVENING. THE HEAVIEST PRECIPITATION IS EXPECTED TO FALL BEFORE SNOW
LEVELS DROP...BUT WEST TO NORTHWEST 30 TO 40 KT 850MB FLOW WILL ACT
ON A DEEP CONDITIONALLY UNSTABLE AIRMASS TO PRODUCE AMPLE SHOWERS
OVER THE CASCADES SATURDAY AFTERNOON INTO EARLY SUNDAY. AS A
RESULT...MOTORISTS SHOULD BE PREPARED FOR WINTER LIKE DRIVING
CONDITIONS OVER WILLAMETTE AND SANTIAM PASSES AND AROUND GOVERNMENT
CAMP ALONG HIGHWAY 26 SATURDAY AFTERNOON INTO EARLY SUNDAY. PYLE
.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY.
THE LOW PRESSURE SYSTEM WILL EXIT THE REGION SUNDAY THOUGH SOME
SHOWERS WILL PERSIST BEHIND THE FRONT WITH THE ONSHORE NEAR-SURFACE
FLOW. SNOW SHOULD CONTINUE IN THE CASCADES SUNDAY ALONG WITH SOME
WINDY CONDITIONS. SNOW LEVELS WILL DROP TO AROUND OR JUST BELOW 3000
FT SUNDAY AS COOL NORTHWESTERLY FLOW ALOFT BUILDS OVER THE PACIFIC
NORTHWEST. SOME SHORTWAVE ENERGY WILL ENHANCE SHOWER CHANCES EARLY
NEXT WEEK AND THE NEXT SYSTEM SHOULD TUESDAY. WHILE THE FORECAST
MODELS EXHIBIT SOME VARIATIONS WITH RESPECT TO THE FINER DETAILS OF
TIMING PERIODS OF PRECIPITATION THROUGH THE MIDDLE OF NEXT WEEK...IT
IS CLEAR THAT WE ARE SHIFTING TO A MORE SEASONAL TYPE OF PATTERN.
HIGHS TEMPERATURES WILL BE NOTICEABLY COOLER FOR THE FIRST HALF OF
NEXT WEEK...AND MAX AND MIN TEMPERATURES SHOULD EACH RUN SEVERAL
DEGREES BELOW NORMAL THROUGH THE PERIOD. CULLEN
&&
.AVIATION...MOSTLY MID LEVEL CLOUDS GREATER WITH BASES HIGHER THAN
5000 FEET RESULTING IN A FEW SPRINKLES THIS EVENING AND TONIGHT
THOUGH REMAINING VFR. EXPECT ENOUGH LIFT WITH THE FRONT TO LOWER
CIGS TO 5000 FT OR LOWER OVERNIGHT....WITH MVFR CONDITIONS
POSSIBLE AT THE COAST. MVFR BECOMES INCREASINGLY POSSIBLE FOR THE
INLAND TERMINALS AFTER DAYBREAK OR LATER THU MORNING WITH LIGHT
RAIN OR DRIZZLE. HIGHEST CONFIDENCE FOR MVFR WILL BE LATE MORNING
TO EARLY AFTERNOON. WITH THE ABUNDANT LOWER LEVEL MOISTURE
ARRIVING...IFR CONDITIONS ARE POSSIBLE. THE COLD FRONT PASSAGE
OCCURS LATER IN THE AFTERNOON WHICH SHOULD HELP TO SCOUR OUT LOWER
CIGS...BUT LIGHT FLOW WILL BRING IFR POTENTIAL THU NIGHT.
KPDX AND APPROACHES...VFR WILL PREVAIL THROUGH AT LEAST 12Z THU.
LIGHT RAIN OR DRIZZLE MAY DEVELOP AROUND 12Z FOR A THREAT OF MVFR.
THE WARM-FRONTAL NATURE OF THE INCOMING SYSTEM COULD ALSO LEAD TO
IFR OR LOW-END MVFR THU MORNING.
&&
.MARINE...WEAK FRONT NEAR THE NEAR SHORE WATERS IN THE NORTH ZONES
AND
OVER THE OUTER WATERS FOR THE SOUTH ZONES. WIND ARE GUSTING
TO AROUND 25 KT AT BUOY 46029 AND NOW THE COASTAL WINDS SITES ARE
PICKING GUSTING IN THE 20 TO 25 KT RANGE. WINDS HAVE EASED OVER
THE OUTER WATERS IN THE NORTH SO HAVE DROPPED ADVISORY FOR THAT
AREA. THE HRRR MODEL SUPPORTS THAT IDEA AS WELL AS MAINTAINING
STRONGER WINDS NEAR SHORE EARLY THIS MORNING. ALSO CANNOT RULE
OUT A FEW GUSTS ALONG THE CENTRAL OREGON COASTAL INNER WATERS TO
25 KT FOR THIS MORNING.
A MUCH STRONGER SYSTEM WILL IMPACT THE WATERS LATE FRIDAY NIGHT
AND SAT. MODEL AGREEMENT ON THE TRACK OF THE LOW IS LOW. RUN TO RUN
CONSISTENCY IS ALSO LOW...BUT BETTER THAN 2 DAYS AGO. THE 00Z ECMWF
AND NAM TAKES THE LOW FURTHEST SOUTH TOWARD THE SOUTH WA COAST
WHILE THE GFS AND GEM FURTHEST NORTH TO THE NORTH WA COAT AND
SOUTHERN VANCOUVER ISLAND RESPECTIVELY. PLAN ON WEIGHTING THE
FORECAST CLOSEST TO THE GFS WHICH LOOKS LIKE A GOOD AVERAGE TRACK.
EXPECT GALES TO DEVELOP OVER THE WATERS EARLY SAT MORNING AND
CONTINUE THROUGH THE AFTERNOON. THE POST-FRONTAL W-NW WIND COULD
BE JUST AS STRONG...IF NOT A BIT STRONGER...THAN THE PRE-FRONTAL
WIND. THERE IS THE POTENTIAL FOR SOME STORM-FORCE GUSTS OVER THE
FAR N WATERS. THE WIND SETTLES DOWN FAIRLY QUICKLY SAT EVENING.
SEAS LIKELY TO SUBSIDE BELOW 10 FT SUN AFTERNOON.
SEAS REMAIN WELL BELOW 10 FT THROUGH FRI NIGHT...BUT MAKE A
SUBSTANTIAL JUMP SAT MORNING. EXPECT SEAS AROUND 15 FT SAT
MORNING ...WIND-WAVE DOMINATED. COULD SEE HIGHER SEAS SHOULD THE
GALE- FORCE NWLY WIND END UP STRONGER AND OF LONGER DURATION OVER
THE FETCH AREA. W-NW SWELL APPROACHING 20 FT IMPACTS THE FAR N
WATERS SAT AFTERNOON. WEISHAAR/MH
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 7 AM PDT THIS
MORNING FOR COASTAL WATERS FROM CAPE SHOALWATER WA
TO CASCADE HEAD OR OUT 60 NM.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
1027 AM EDT THU OCT 31 2013
.DISCUSSION...MINOR UPDATE TO TODAY. LIGHT SHOWERS OR SPRINKLES
WILL CONTINUE EARLY TODAY. UPPER FEATURE AIDED THE LIFT WILL EXIT
TO THE NE. LOWEST LAYERS REMAIN RELATIVELY DRY WITH CURRENT AND
UPSTREAM CLOUD DECKS IN THE MID LEVELS. HRRR AND RUC MORE
AGGRESSIVE WITH EARLY PRECIPITATION BUT NOR CONCERNED ABOUT MUCH IN
WAY OF MEASURABLE PCPN. SOME EVAPORATIVE COOLING OCCURRING THIS
MORNING. THIS COUPLED WITH EXTENSIVE CLOUD CANOPY LOWERED AFTN
TEMPS A COUPLE OF DEGREES. LATE DAY WARM AIR SURGE COULD EXCEED
THESE VALUES. INCREASED WINDS ON TRACK FOR THIS AFTERNOON. BEST
PCPN COVERAGE EXPECTED OVERNIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 73 61 72 45 65 / 50 100 20 10 10
KNOXVILLE MCGHEE TYSON AIRPORT, TN 72 59 73 45 61 / 50 100 20 10 20
OAK RIDGE, TN 72 59 73 44 61 / 50 100 20 10 20
TRI CITIES AIRPORT, TN 70 57 71 43 57 / 30 100 30 10 30
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...WIND ADVISORY FROM 4 PM THIS AFTERNOON TO 7 AM EDT FRIDAY FOR
THE FOLLOWING ZONES: CHEROKEE...CLAY.
TN...WIND ADVISORY FROM 4 PM EDT /3 PM CDT/ THIS AFTERNOON TO 7 AM
EDT /6 AM CDT/ FRIDAY FOR THE FOLLOWING ZONES: BLEDSOE...
BLOUNT SMOKY MOUNTAINS...CAMPBELL...CLAIBORNE...COCKE SMOKY
MOUNTAINS...EAST POLK...JOHNSON...MARION...MORGAN...SCOTT
TN...SEQUATCHIE...SEVIER SMOKY MOUNTAINS...SOUTHEAST
CARTER...SOUTHEAST GREENE...SOUTHEAST MONROE...UNICOI.
VA...WIND ADVISORY FROM 4 PM THIS AFTERNOON TO 7 AM EDT FRIDAY FOR
THE FOLLOWING ZONES: LEE...RUSSELL...WASHINGTON...WISE.
&&
$$
SON
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
901 AM CDT THU OCT 31 2013
.UPDATE...THIS MORNING
ISSUED AT 901 AM CDT THU OCT 31 2013
WITH VISIBILITIES RUNNING AROUND A QUARTER MILE...EXPANDED THE
DENSE FOG ADVISORY SOUTH TO VERNON COUNTY. ALSO DECIDED TO EXTEND
IT UNTIL NOON. WITH THE SREF AND HRRR SHOWING THAT THE
VISIBILITIES WILL IMPROVE RAPIDLY BETWEEN 31.15Z AND 31.18Z...DO
NOT ANTICIPATE HAVING TO EXTEND THIS ADVISORY INTO THE AFTERNOON.
&&
.SHORT TERM...(TODAY AND TONIGHT)
213 AM CDT THU OCT 31 2013
MAIN FOCUS DURING THE SHORT TERM PERIOD IS THE PRECIPITATION AS THE
LOW PRESSURE SYSTEM TRAVERSES THE AREA. ALSO WATCHING FOG TRENDS
WITH DENSE FOG ACROSS PARTS OF THE REGION. 07Z SURFACE ANALYSIS
SHOWS THE LOW CENTER SOMEWHERE BETWEEN KRST AND KDEH...MOVING EAST.
FRONTAL BOUNDARY TRAILING SOUTH FROM THE LOW THROUGH CENTRAL IA.
RADAR LOOP SHOWS SHOWERS AND A FEW EMBEDDED THUNDERSTORMS AHEAD OF
THE LOW...WITH WIDESPREAD LIGHT RETURN ALONG AND BEHIND...
INDICATIVE OF DRIZZLE OR VERY LIGHT RAIN. SURFACE OBSERVATIONS
SHOW DENSE FOG OVER NORTHERN WI...WHERE A DENSE FOG ADVISORY
REMAINS IN EFFECT. THICK FOG IS ALSO OCCURRING ALONG THE FRONT AS
IT MOVES EAST.
IT WILL TAKE SOME TIME...BUT THE MAIN SHORT WAVE TROUGH AND LOW
SYSTEM WILL TRACK NORTHEAST OUT OF THE AREA BY TONIGHT. WEAK FLOW
AND WEAK LIFT WILL KEEP THE THREAT FOR VERY LIGHT PRECIPITATION
AROUND THROUGH MUCH OF THE DAY...SO WILL HANG ONTO THE LOW CHANCES
UNTIL THE EVENING HOURS. COLD ADVECTION BEHIND THE FRONT WILL KEEP
TEMPERATURES FROM MOVING MUCH. IN FACT...THEY SHOULD FALL FOR A
GOOD PORTION OF THE DAY...WITH PERHAPS A FEW DEGREES OF AN UPWARD
TICK DURING THE AFTERNOON. TONIGHT SHOULD SEE THE MERCURY DIP INTO
THE 30S. IT COULD GET A BIT COOLER IF THE CLOUDS BREAK UP MORE...
SO WILL HAVE TO WATCH THAT TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
213 AM CDT THU OCT 31 2013
A FAST-MOVING SHORT WAVE TROUGH WILL ZIP SOUTHEAST FROM ALBERTA
AND SASKATCHEWAN INTO MN/IA BY FRIDAY. MOISTURE WILL BE LIMITED...
BUT THERE WILL BE AMPLE LIFT AND SOMEWHAT STEEP LAPSE RATES WITH
THE COOLER AIR IN PLACE BEHIND THE DEPARTING SYSTEM. ANTICIPATE
SOME SCATTERED SHOWERS TO DEVELOP AND MOVE THROUGH THE AREA FROM
LATE FRIDAY AFTERNOON INTO FRIDAY NIGHT. DO NOT EXPECT RAIN TO
AMOUNT TO TOO MUCH. WEAK CHANNELED VORTICITY WILL BE DROPPING INTO
THE BACK SIDE OF THE DEEPENING LONG WAVE TROUGH OVER THE OHIO
VALLEY...AND THIS COULD PROVIDE SOME WEAK SUPPORT TO GENERATE A
FEW SHOWERS OVER PARTS OF WI DURING THE DAY SATURDAY. AGAIN...IF
THIS DOES HAPPEN...DO NOT EXPECT IT TO AMOUNT TO VERY MUCH. `
HIGH PRESSURE THEN BUILDS IN...PROVIDING FOR A COOL NIGHT SATURDAY
NIGHT AND A COOL BUT PLEASANT DAY ON SUNDAY. BUT THE UNSETTLED
WEATHER PATTERN RESULTS IN ANOTHER LONG WAVE TROUGH DIGGING INTO
THE ROCKIES ON MONDAY...WHICH FORMS A STRONG LOW PRESSURE SYSTEM
ACROSS THE DAKOTAS AND MANITOBA. THIS ONE LOOKS TO REMAIN NORTH OF
THE REGION...AS IT TRACKS THROUGH WESTERN ONTARIO INTO JAMES BAY.
BUT THE TRAILING COLD FRONT WILL MOVE THROUGH THE REGION MONDAY...
BRINGING ANOTHER CHANCE FOR SHOWERS. AND ANOTHER SHORT WAVE TROUGH
ROUNDING THE BASE OF THE MAIN TROUGH WILL EJECT UP ACROSS THE
PLAINS AND TOWARD THE GREAT LAKES REGION FOR TUESDAY INTO
WEDNESDAY. OVERALL TEMPERATURES LOOK TO BE NEAR NORMAL...WITH NO
REAL CONNECTION TO THE ARCTIC AIR SEEN IN THE FORESEEABLE FUTURE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 704 AM CDT THU OCT 31 2013
LIFR VIS/CIGS CURRENTLY OCCURRING ACROSS MUCH OF THE REGION AND AT
THE TAF SITES WITH THE MAIN INITIAL QUESTION FOR THE FORECAST
BEING WHEN THESE CONDITIONS MAY IMPROVE. CALM WINDS AND HIGH
RELATIVE HUMIDITY ASSOCIATED WITH A LOW PRESSURE SYSTEM CENTERED
OVER THE REGION HAS LED TO THIS FOG FORMATION. THE COLD FRONT
ASSOCIATED WITH THE LOW HAS GONE THROUGH RST AND WILL GO THROUGH
LSE BY MID MORNING. WHILE CEILINGS STAY IFR OR WORSE AFTER THE
FRONT COMES THROUGH...THE VISIBILITY AT LEAST IMPROVES ABOVE
1/4SM. THE IFR LOOKS LIKE IT COULD HOLD ON THROUGH MUCH OF THE DAY
THOUGH THERE HAS BEEN SOME IMPROVEMENT TO MVFR ACROSS SOUTH
CENTRAL MINNESOTA ALREADY. PLAYED IT PESSIMISTIC AS THE SURFACE
LOW WILL NOT TRACK TO FAST TO THE EAST AND THE MAIN UPPER LEVEL
TROUGH IS STILL OFF TO THE WEST. CONDITIONS WILL AT LEAST REMAIN
MVFR THROUGH TOMORROW MORNING AS A SECONDARY TROUGH COMES THROUGH
THE REGION TONIGHT AND HELPS TO KEEP SOME LOW LEVEL MOISTURE
AROUND. THERE COULD BE SOME LIGHT RAIN THAT OCCURS WITH THIS
FEATURE AS WELL...BUT THE BETTER FORCING LOOKS LIKE IT STAYS JUST
NORTH OF THE TAF SITES.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...DENSE FOG ADVISORY UNTIL NOON CDT TODAY FOR WIZ017-029-032>034-
041>044-053.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...BOYNE
SHORT TERM...MW
LONG TERM...MW
AVIATION...HALBACH
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
320 PM EDT THU OCT 31 2013
.SHORT TERM /TONIGHT THROUGH FRIDAY/...
OBVIOUSLY THE MAIN QUESTION THROUGH THE SHORT TERM IS TIMING OF THE
FRONT AND PRECIP ASSOCIATED WITH IT. DEEP UPPER TROUGH OVER THE
CENTER OF THE COUNTRY IS BEGINNING TO LIFT OUT. STRONG SURFACE LOW
OVER THE GREAT LAKES WILL CONTINUE MOVING NORTHEAST...DRAGGING A
COLD FRONT THROUGH THE SOUTHEAST TONIGHT AND TOMORROW AS THE SURFACE
LOW OCCLUDES. MOST OF THE PRECIP WILL BE OUT OF THE AREA BY THE END
OF THE SHORT TERM WITH THE EXCEPTION OF EXTREME SOUTHEAST ZONES.
STRONG SOUTHERLY FLOW IS IN PLACE ACROSS THE SOUTHEAST AHEAD OF THE
FRONT AT AFD TIME...WITH SOME PATCHY RETURNS SHOWING UP HERE AND
THERE ON RADAR. IT IS DOUBTFUL THAT ANYTHING IS REACHING THE GROUND
FROM THESE WEAK ECHOES BUT THEIR EXISTENCE DOES LEND SOME CREDENCE
TO THE HRRR SOLUTION FOR THIS AFTERNOON AND EARLY EVENING. GUIDANCE
IS ALL REALLY COMING INTO AGREEMENT WITH THE PROGRESSION OF THE
FRONT AND IT LOOKS LIKE FOR THE MOST PART THE CWA WILL REMAIN
PRECIP-FREE UNTIL AFTER 00Z. MAY SEE SOME SPRINKLES NORTHWEST BUT
REALLY HAVE NOT STARTED INCREASING POPS UNTIL AFTER THAT POINT.
SHOULD ENCROACH UPON THE METRO AREA NEAR OR JUST AFTER MIDNIGHT...
AND TOWARDS CENTRAL GEORGIA /MACON AREA/ BY 12Z. SO TRICK-OR-
TREATING SHOULD BE IN GOOD SHAPE THIS EVENING.
ONTO SOME DETAILS...STARTING WITH QPF...NOT OVERLY CONCERNED ABOUT
OVERALL BASIN-AVERAGE VALUES WHICH GENERALLY REMAIN BELOW AN INCH
THROUGH THE EVENT. NAM IS A LITTLE MORE AGGRESSIVE WITH QPF VALUES
ESPECIALLY 12-18Z FRIDAY BUT IT SEEMS TO BE A BIT OF AN OUTLIER.
CANNOT RULE OUT SOME ISOLATED PRECIP ISSUES ESPECIALLY WITH ANY
OROGRAPHIC ENHANCEMENT IN THE NORTH GEORGIA MOUNTAINS...BUT THAT
WILL HAVE TO BE HANDLED ON A CASE-BY-CASE BASIS.
OTHER CONCERN IS SEVERE POTENTIAL. AS IS ALWAYS THE CASE...NAM IS
MORE UNSTABLE THAN OTHER GUIDANCE BUT THE GFS IS COMING IN WITH
SLIGHTLY HIGHER MUCAPE FRIDAY AFTERNOON THAN PREVIOUS RUNS WITH OVER
700 J/KG...NOT THAT DIFFERENT FROM THE NAM. EXPECT THAT ANY PRECIP
THIS EVENING AND THROUGH MOST OF THE OVERNIGHT PERIOD WILL REMAIN AS
SHOWERS...THOUGH DID BRING SLIGHT CHANCE THUNDER IN STARTING AT 06Z
NORTHWEST...BUT GENERALLY ONLY WHERE POPS ARE LIKELY OR HIGHER.
SWATH OF INSTABILITY WILL BE ACROSS THE METRO AREA BY AROUND
12Z...AND CENTRAL GEORGIA BY 18Z. SO OVERALL VERY...VERY LITTLE
INSTABILITY TO WORK WITH BUT WHEN CONTRASTED WITH THE VERY STRONG
SHEAR...WE CANNOT LET OUR GUARD DOWN. 0-1KM BULK SHEAR VALUES BY 06Z
TONIGHT ARE OVER 40KT IN NORTHWEST GEORGIA...WITH 60-70KT 0-6KM
SHEAR. 0-1KM SHEAR DROPS OFF THROUGH TIME TO GENERALLY BELOW 35KT BY
12Z FRIDAY...AND LESS THAN 30KT BY 18Z FRIDAY...BUT DEEP LAYER SHEAR
REMAINS QUITE STRONG AT OVER 60KT. SO WE HAVE A TREND OF INCREASING
INSTABILITY FROM 06-18Z FRIDAY AND DECREASING SHEAR. SOMEWHERE IN
THERE A PERFECT JUXTAPOSITION CANNOT BE RULED OUT. SPC HAS A SEE
TEXT FOR DAY2 ACROSS CENTRAL GEORGIA AND SREF GUIDANCE SEEMS TO
POINT TO FRIDAY LATE MORNING AND EARLY AFTERNOON BEING OF GREATER
CONCERN THAN OVERNIGHT TONIGHT. SHERB PARAMETER...WHICH WAS
CALIBRATED TO INDICATE A FAVORABLE ENVIRONMENT FOR HIGH SHEAR LOW
CAPE SEVERE WEATHER...IS MAXIMIZED LATE THIS EVENING IN NORTHWEST
GEORGIA WITH ANOTHER MAXIMUM JUST BEFORE 18Z TOMORROW /RIGHT BEFORE
FROPA/ AROUND THE METRO AREA.
OF COURSE...ALL THAT SAID /OR WRITTEN/...OVERALL CONCERN FOR SEVERE
IS NOT PARTICULARLY HIGH. IT JUST CANNOT BE RULED OUT.
USED A BLEND FOR TEMPERATURES BUT PULLED BACK ON BIAS ADJUSTMENT DUE
TO WIDESPREAD CLOUDS AND IMPENDING AIRMASS CHANGE.
TDP
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
COLD FRONT EXPECTED TO EXIT THE SE CWA FRIDAY NIGHT WITH PRECIP
CHANCES DIMINISHING. UPPER TROUGH MOVES ACROSS THE AREA ON SATURDAY
WITH SOME MOISTURE ASSOCIATED OVER THE FAR NORTHERN COUNTIES. CAN
NOT RULE OUT SOME LIGHT SHOWERS OR SPRINKLES DURING THE DAY.
TEMPERATURES TRENDING TO BELOW NORMAL INTO EARLY NEXT WEEK.
BDL
PREVIOUS DISCUSSION...
MODELS IN GOOD AGREEMENT WITH CONTINUING TO PUSH THE COLD FRONT AND
ASSOCIATED MOISTURE OUT OF THE CWA BY SATURDAY MORNING LEAVING THE
LONG TERM DRY UNTIL THE MIDDLE OF NEXT WEEK. THE H5 TROUGH WILL EXIT
THE U.S. SATURDAY WITH A RIDGE BUILDING OVER THE EASTERN U.S. SUNDAY
THROUGH EARLY NEXT WEEK. SOME DIFFERENCES IN THE NEXT SYSTEM APPEAR
BETWEEN THE 00Z GFS AND THE 12Z ECMWF WITH THE ECMWF HOLDING ONTO
THE H5 HIGH OVER THE SOUTHEAST WHILE THE GFS WEAKENS THE HIGH AND
BRINGS A FAST MOVING TROUGH AND ASSOCIATED COLD FRONT INTO THE CWA
BY WEDNESDAY NIGHT AND THURSDAY. AT THIS TIME WILL MAINTAIN CHANCE
POPS BEGINNING WEDNESDAY.
17
&&
.AVIATION...
18Z UPDATE...
VFR TO START THE PERIOD WITH GUSTY S TO SSE WINDS. CONDITIONS
DETERIORATE ABOUT 06Z WHEN CIGS DROP TO MVFR AND SHRA MOVES IN.
CIGS CONTINUE TO DROP AND EXPECT IFR BY 09Z. CANNOT RULE OUT LIFR
TOWARD SUNRISE BUT FOR NOW HAVE ONLY KEPT SCT004. BEST CHANCE TSRA
APPROX 15-18Z FRIDAY AND HAVE INTRODUCED PROB30 AT THAT POINT BUT
EXPECT RAPID CLEARING AFTER 18Z AFTER THE FRONT PUSHES THROUGH.
WINDS WILL VARY BETWEEN SSE AND SSW BUT SHOULD BE SOLIDLY ON THE W
SIDE BY 06Z.
//ATL CONFIDENCE...18Z UPDATE...
MEDIUM ON ALL ELEMENTS.
TDP
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 64 70 48 69 / 100 100 10 0
ATLANTA 63 71 50 67 / 100 100 10 0
BLAIRSVILLE 58 71 43 61 / 100 80 10 20
CARTERSVILLE 65 73 44 67 / 100 70 5 0
COLUMBUS 69 73 51 72 / 90 100 10 0
GAINESVILLE 62 72 49 67 / 100 100 10 10
MACON 67 74 49 74 / 60 100 20 0
ROME 63 72 43 66 / 100 40 5 0
PEACHTREE CITY 66 72 45 69 / 100 100 10 0
VIDALIA 66 78 58 76 / 30 90 80 0
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...TDP
LONG TERM....BDL
AVIATION...TDP
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
313 PM CDT THU OCT 31 2013
.DISCUSSION...
310 PM CDT
THE FORECAST CHALLENGES THIS FINAL DAY OF OCTOBER WERE FOCUSED
EARLY ON WITH CONVECTIVE CHANCES...RAIN TIMING AND AMOUNTS...AND
WINDS THROUGH THIS EVE. OTHERWISE THE WEATHER LOOKS FAIRLY CALM
DURING THE FIRST WEEKEND OF NOV BEFORE THE NEXT PRONOUNCED MID-
LATITUDE SYSTEM POTENTIALLY DURING MIDWEEK.
SYNOPSIS...PROGRESSIVE AND VERY-WELL DEFINED UPPER WAVE ACROSS
CENTRAL MO THIS MID-AFTERNOON WILL ROTATE EAST OVER THE AREA THIS
EVENING...BRINGING A LARGE SCALE NEGATIVE TILT TO THE MIDWEST TROUGH
AS A WHOLE. DRY SLOT OF THE SYSTEM IS ENCROACHING IN ON THE AREA
WITH MODE OF RAIN ACTIVITY BECOMING MORE SHOWER-LIKE ACROSS
CENTRAL IL AND INTO THE SOUTHERN FORECAST AREA. CONSOLIDATING
SURFACE LOWS OVER THE CWA ARE A RESULT OF THE DEEP UPWARD
ASCENT...AND 5-7MB/3HR PRESSURE FALLS ARE CURRENTLY BEING OBSERVED
OVER MUCH OF THE AREA. THIS LOW WILL BE VERY NEAR A BOMB BY
DEFINITION THROUGH TONIGHT AS IT DEEPENS INTO LOWER MICHIGAN AND
TO 970-975MB JUST EAST OF LAKE HURON BY EARLY FRIDAY. THE SURFACE
COLD FRONT IS DRAPED ACROSS THE FAR WESTERN FORECAST AREA AS OF 3
PM AND THIS WILL INCH EASTWARD THIS EVE...WITH CONVECTIVE CHANCES
MAINLY AHEAD OF THIS WHERE OVERALL HIGHER MOISTURE
CONTENT/TRANSPORT REMAINS.
LATE THIS AFTERNOON AND TONIGHT...AS MID-LEVEL JET AND DRY SLOT
ROTATE OVERHEAD...THE SHOWER MODE SHOULD CONTINUE TO BECOME MORE
PREVALENT THROUGH LATE THIS AFTERNOON. THERE HAD BEEN A BAND OF
MORE ROBUST SHOWERS NEAR THE FRONT IN CENTRAL IL WITH 30-40 KT
WINDS JUST OFF THE SURFACE BUT THAT HAS DISSIPATED SINCE 230 PM.
IN ADDITION...MORE SHOWERS AND STORMS CONTINUE TO FIRE OVER
SOUTHERN IL...AND FURTHER SOUTH THAN THAT...ALL WHICH MAY BEGIN TO
LIMIT COVERAGE OF SHOWERS AND STORMS THAT DEVELOP THIS FAR NORTH
THROUGH THE NEXT SEVERAL HOURS. STILL EXPECT AT LEAST SCATTERED
DEVELOPMENT AHEAD OF THE FRONT AND ANY SHOWERS OR STORMS
IMMEDIATELY ON THE FRONT ITSELF WILL REMAIN THE MOST PROBABLE TO
HAVE AT LEAST A LIMITED GUSTY WIND POTENTIAL. WITH SCATTERING OF
CLOUDS LOOKING HIGHLY UNLIKELY TO MAKE IT TO THE SOUTHEAST
FORECAST AREA...THE POTENTIAL TO REALIZE LOW-LEVEL CAPE ALSO LOOKS
HIGHLY DIMINISHED. WHILE THE FRONT WILL END THE POTENTIAL FOR
THUNDER BY 7 PM...THERE WILL LINGER A COUPLE HOUR PERIOD BEHIND
THE FRONT INTO EARLY TO MID EVE WHERE SOME SCATTERED SHOWERS MAY
PERSIST AS THE UPPER LOW PASSES OVERHEAD.
AS THE PRESSURE RISES BEGIN TO BE SEEN ASSOCIATED WITH THE
DOWNWARD MOTION OF THE JET AND LOW-LEVEL COLD AIR ADVECTION...THE
ISALLOBARIC COUPLET WILL BECOME MORE AND MORE PRONOUNCED. WHILE
THERE IS LITTLE IN THE WAY OF WIND UPSTREAM TO OUR WEST AND
SOUTHWEST...EXPECT THAT HIGHER GUSTS WILL PRETTY MUCH DEVELOP
RIGHT OVER THE CWA...PARTICULARLY THE SOUTH AND EAST BY EARLY EVE.
LOOKING AT THE LATEST RAP AND NAM SOUNDINGS CONTINUE TO SUPPORT
TEMPORARY GUST POTENTIAL AROUND 40 MPH BETWEEN 6 AND 10 PM OR SO.
THE BEST CHANCES REMAIN SOUTH OF CHICAGO BUT CANNOT RULE OUT SOME
OF THE WIND POTENTIAL REACHING THAT FAR NORTH.
FRIDAY...NORTHWEST FLOW WILL DEVELOP OVER THE AREA INTO THE FIRST
HALF OF THIS WEEKEND...WITH A COUPLE UPPER SHORT WAVES DIVING OVER
THE AREA FRIDAY AFTERNOON AND MORE SO IN THE EVE. SATURATED LAYER
LOOKS SHALLOW AT FIRST BUT LATE IN THE AFTERNOON INTO THE
EVE...NAMELY OVER FAR NORTHERN AND NORTHEASTERN IL...IT LOOKS DEEP
ENOUGH TO SUPPORT SOME SHOWERS. SO MAINTAIN THE CHANCES WHICH
GENERALLY HAD A GOOD LOOKING ORIENTATION AND MAGNITUDE IN OUR
FORECAST. HIGHS WILL BE BACK DOWN INTO THE 50S...WITH A FEW UPPER
40S NEAR THE STATE LINE.
THIS WEEKEND...LITTLE IN THE WAY OF CHANGE TO THIS PART OF THE
FORECAST. SAT NIGHT SHOULD BE A COOL NIGHT WITH RIDGING
OVERHEAD...BUT ALL IN ALL ONLY ABOUT 5 DEGREE BELOW NORMAL.
MTF
LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...
PRIMARY CONCERN IN THE EXTENDED PERIOD IS WHAT COULD POTENTIALLY BE
ANOTHER SIGNIFICANT RAIN EVENT FOR THE CWA LATER TUESDAY INTO
WEDNESDAY. THERE IS GOOD AGREEMENT AMONGST OPERATIONAL AND ENSEMBLE
GUIDANCE IN THE MID RANGE IN THE UPPER PATTERN TRANSITIONING TO
BROAD TROUGHING OVER WESTERN NOAM AND A RIDGE SETTING UP OVER THE
EASTERN THIRD OF THE CONUS...AND THIS STRENGTHENING TO ALMOST SUMMER
TIME HEIGHTS OFF THE SOUTHEAST COAST BY TUESDAY AND
WEDNESDAY...NEARING 590 DM. THIS WILL PUT OUR REGION INTO BROAD
SOUTHWEST FLOW ALOFT. AT THE SURFACE...HIGH PRESSURE OVER THE AREA
DURING THE WEEKEND WILL SLIDE EAST AND STRENGTHEN OVER THE NORTHEAST
TUESDAY AND WEDNESDAY...WHILE THE WESTERN TROUGH WILL SPUR INITIALLY
WEAK SURFACE CYCLOGENESIS OVER THE SOUTHERN AND CENTRAL PLAINS. THIS
LOW WILL STRENGTHEN AND THEN TRACK TOWARD THE NORTHERN LAKES ON
WEDNESDAY.
INCREASING WAA AND STEADY SOUTHEAST FLOW WILL RESULT IN A MILDER
NIGHT SUNDAY NIGHT...WITH TEMPERATURES WARMING TO 4 TO 5 DEGREES
ABOVE CLIMO ON MONDAY. RAIN CHANCES ARRIVE PRIMARILY OVER NORTHWEST
HALF OF CWA MONDAY NIGHT AS LOW LEVEL JET INCREASES MOISTURE
TRANSPORT WITH A WARM FRONT LIFTING NORTH. POPS WILL CONTINUE TO BE
FOCUSED NORTHWEST HALF ON TUESDAY...WITH THERMAL PROFILES POSSIBLY
SUPPORTIVE OF 60+ DEGREE READINGS IN THE SOUTHEAST HALF DEPENDING ON
CLOUD COVER. TUESDAY NIGHT INTO WEDNESDAY IS THE BIGGEST PERIOD OF
CONCERN AS LOW LEVEL JET WILL FURTHER INCREASE TO 40 TO POSSIBLY 50
KT...WITH TONGUE OF PWAT AROUND OR A BIT OVER 1.25 INCHES
TRANSPORTED OVER AREA...WHICH IS ALMOST 250% OF NORMAL FOR NOVEMBER.
EXPECTING TO SEE PERIODS OF RAIN WITH SHORTWAVES EMANATING FROM
TROUGH TO WEST LIKELY RIDING INTO AREA IN SOUTHWEST MID FLOW. STRONG
SURFACE SOUTHERLY FLOW WILL ALSO LIKELY RESULT IN LOW TEMPERATURES
AROUND OR ABOVE NORMAL HIGHS...AT LEAST INTO THE LOW 50S AND RISING
TEMPERATURES TOWARD DAYBREAK WEDNESDAY A NICE SPRINGBOARD FOR
POSSIBLY SEEING SOME 60 DEGREE READINGS AGAIN IN SOUTHEAST HALF OF
CWA. PRIOR TO COLD FRONT PASSAGE ON WEDNESDAY...SYNOPTIC PATTERN
APPEARS FAVORABLE FOR ANOTHER POSSIBLY 1 INCH PLUS RAIN EVENT.
DESPITE IT BEING SEVERAL DAYS OUT...FELT THERE WAS ENOUGH AGREEMENT
AND RUN TO RUN CONSISTENCY IN GUIDANCE TO MAINTAIN LIKELY POPS IN
TUES NIGHT THROUGH WEDNESDAY PERIOD.
MAIN UNCERTAINTY IS WITH HOW PROGRESSIVE TROUGH PASSAGE IS...AS
LATEST OPERATIONAL ECMWF TRENDED FASTER. GFS ENSEMBLES KEEP SOME LOW
POPS FOR EASTERN CWA INTO THURSDAY BUT IF TREND OF OPERATIONAL
MODELS TO HAVE SURFACE HIGH OVER AREA ON THURS COME TO
FRUITION...WILL LIKELY BE ABLE TO REMOVE MORNING POPS. 850 MB TEMPS
COOLING TO MID MINUS SINGLE DIGITS AND 925 MB AROUND 0C ON THURSDAY
SUPPORTS HIGHS A BIT BELOW NORMAL IN UPPER 40S.
CONFIDENCE IN SEEING RAIN TUESDAY INTO WEDNESDAY...MEDIUM-HIGH.
RC
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* PERIODS OF IFR CIGS THROUGH EARLY EVENING.
* PERSISTENT RAIN WITH LOWER VIS DOWN TO 2 MILES IN THE HEAVIER
RAIN THROUGH LATE AFTERNOON/EARLY EVENING.
* PERIOD OF GUSTY WEST-NORTHWESTERLY WINDS BY EARLY THIS EVENING
IN THE WAKE OF THE COLD FRONT.
KJB
//DISCUSSION...UPDATED 18Z...
THE WEATHER WILL CONTINUE TO BE MESSY THIS AFTERNOON AND INTO THE
EVENING ACROSS THE REGION AS A POTENT STORM SYSTEM CONTINUES TO
STRENGTHEN AS IT MOVES FROM WISCONSIN TO LOWER MICHIGAN BY THIS
EVENING.
ASIDE FROM A FEW BRIEF BREAKS IN THE LOW CLOUDS...CIGS CONTINUE TO
RESIDE BETWEEN 800 TO 1000 FEET ACROSS THE AIRSPACE EARLY THIS
AFTERNOON...AND THIS WILL CONTINUE TO BE THE CASE THROUGH THE DAY.
MORE PERSISTENT HEAVIER RAIN WILL CONTINUE TO OVERSPREAD THE AREA
THIS AFTERNOON AHEAD OF AN APPROACHING COLD FRONT. VISIBILITIES IN
THE HEAVIER RAIN COULD FALL TO 2 TO 3 MILES FOR A PERIOD THIS
AFTERNOON. CIGS AND VIS SHOULD IMPROVE AND RAIN WILL END BY MID TO
LATE EVENING AS THE SYSTEM MOVES NORTHEAST ACROSS NORTHERN LOWER
MICHIGAN.
WINDS WILL REMAIN AROUND 7 TO 10 KT OUT OF THE SOUTH AHEAD OF THIS
COLD FRONT. HOWEVER...THIS COLD FRONT WILL PUSH ACROSS THE KRFD AREA
AROUND 20 UTC...AND AROUND 2230 TO 23 UTC AT THE EASTERN TAF SITES.
ONCE THIS FRONT PUSHES THROUGH...EXPECT A RAPID WIND SHIFT OUT OF
THE WEST-NORTHWEST. IT ALSO APPEARS THAT THERE COULD BE A PERIOD OF
SOME FAIRLY STRONG WINDS AS WELL IN THE WAKE OF THIS FRONT EARLY
THIS EVENING. WIND GUSTS COULD APPROACH OR EVEN EXCEED 30 KT FOR A
SHORT ONE OR TWO HOUR PERIOD THIS EVENING AFTER 23 UTC. THE WINDS
WILL REMAIN OUT OF THE WEST INTO FRIDAY...BUT WIND GUSTS WILL ABATE
SOME.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM TO HIGH CONFIDENCE WITH CEILINGS/TRENDS.
* MEDIUM TO HIGH CONFIDENCE WITH GUSTY WINDS THIS EVENING.
KJB
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...CHANCE OF SHOWERS...OTHERWISE VFR.
SATURDAY...SLIGHT CHANCE OF SHOWERS...OTHERWISE VFR.
SUNDAY...VFR.
MONDAY...CHANCE OF SHOWERS LATE...OTHERWISE VFR.
TUESDAY...CHANCE OF SHOWERS...OTHERWISE VFR.
WEDNESDAY...CHANCE OF SHOWERS...OTHERWISE VFR.
RODRIGUEZ
&&
.MARINE...
209 PM CDT
DEVELOPING STORM SYSTEM THIS EVENING AS IT NEARS LAKE MICHIGAN. NO
CHANGES TO THE GOING HEADLINES OF GALES FOR THE ENTIRE LAKE AND
INDIANA NEARSHORE WATERS.
AN ELONGATED TROUGH OF LOW PRESSURE STRETCHED FROM CENTRAL WISCONSIN
SOUTH THROUGH SOUTHWEST ILLINOIS THIS AFTERNOON...AND IS FORECAST TO
CONSOLIDATE INTO A LOW OVER CENTRAL LAKE MICHIGAN EARLY THIS EVENING
AND RAPIDLY DEEPEN. AS THE LOW QUICKLY INTENSIFIES...THE PRESSURE
GRADIENT OVER THE LAKE WILL ALSO TIGHTEN. THIS WILL RESULT IN GALES
DEVELOPING WITH NEARLY 40-44KT ACROSS THE SOUTHERN HALF OF LAKE
MICHIGAN FROM THE WEST. TIMING CONTINUES TO BE AROUND MIDNIGHT. THE
STRONG LOW PRESSURE WILL CONTINUE TO DEEPEN AS IT SLIDES NORTHEAST
ACROSS NORTHEASTERN LAKE HURON INTO EASTERN ONTARIO AND WESTERN
QUEBEC FRI AFTN/EVE. THE GRADIENT WILL THEN QUICKLY DIMINISH LATE
FRI MORNING...WITH GALES ENDING BY MID-MORNING FRI.
WINDS WILL CONTINUE TO BE WESTERLY UNTIL THE UPPER LEVEL TROUGH
ARRIVES FRI EVE...THEN WINDS WILL TURN NORTHWESTERLY. A BROAD RIDGE
OF HIGH PRESSURE CONTINUES TO BE FORECAST TO SLIDE ACROSS THE
CENTRAL/SOUTHERN PLAINS. THIS WILL RESULT IN A PROLONGED PERIOD OF
NORTH/NORTHWEST WINDS FOR SAT. THE GRADIENT DOESN/T COMPLETELY GO
AWAY...WITH SPEEDS REMAINING ARND 10-20KT WITH GUSTS TO 25KT OVER
THE OPEN WATERS. THEN THIS HIGH PRESSURE SLIDES EAST AND STRETCHES
TO COVER LAKE MICHIGAN SAT NIGHT/SUN...WITH A PERIOD OF LIGHTER
WINDS. THE WEATHER REMAINS PROGRESSIVE AND THE HIGH PRESSURE WILL
PUSH EAST WITH WINDS SHIFTING TO SOUTHEASTERLY/SOUTHERLY FOR EARLY
NEXT WEEK.
FORECAST GUIDANCE IS BEGINNING TO POINT TOWARDS ANOTHER STRONG STORM
SYSTEM TO DEVELOP AND APPROACH THE GREAT LAKES REGION FOR THE MIDDLE
PART OF NEXT WEEK.
CONFIDENCE IN GALES TONIGHT/FRI MORNING...HIGH.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 9 PM
THURSDAY.
GALE WARNING...LMZ743-LMZ744-LMZ745...9 PM THURSDAY TO 4 AM
FRIDAY.
GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...9 PM THURSDAY TO 9 AM
FRIDAY.
SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 10 AM
FRIDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1251 PM CDT THU OCT 31 2013
.DISCUSSION...
1210 PM CDT
SOME CHANGES MADE TO FORECAST POPS/THUNDER CHANCES/QPF THROUGH
EARLY...WITH THE MOST MAJOR TO ADD INCREASED WIND GUSTS LATE THIS
AFTERNOON AND THIS EVE. THERE REMAINS SOME CONDITIONAL THREAT FOR
SEVERE WEATHER IN THE FAR SOUTHEAST FORECAST AREA...NAMELY BETWEEN
3 AND 7 PM. DID EXTEND COVERAGE OF CATEGORICAL POPS THROUGH MID-EVE
WITH A TREND FOR A SLOWER DEPARTURE OF RAIN FOR AT LEAST PART OF
THE CWA.
DYNAMIC UPPER LOW ASSOCIATED WITH 200M UPPER LEVEL HEIGHT FALLS
THIS MORNING IS ENTERING WESTERN MO EARLY THIS AFTERNOON...AS IS A
POTENT ASSOCIATED MID-LEVEL JET. NUMEROUS IMPULSES CONTINUE TO BE
SEEN IN ADVANCE OF THIS WHICH CONTINUE TO CAUSE BLOSSOMING OF RAIN
AREAS ACROSS THE REGION...WITH AT TIMES SOME HEAVIER AXES. THE DRY
SLOT IS RACING NORTHEAST ACROSS CENTRAL MO AND SHOULD ARRIVE ATOP
THE SOUTHWEST/SOUTHERN FORECAST AREA AROUND 3 PM. TWO SURFACE LOWS
ARE NOTED NEAR THE SAME MAGNITUDE RIGHT NOW WITH ONE IN WI AND
POSSIBLY A MORE PROBLEMATIC ONE ENTERING WEST CENTRAL IL IN
ASSOCIATION WITH THE PRIMARY WAVE ENTERING MO. THE COLD FRONT
CONNECTS THE TWO AND IS INCHING EASTWARD. THE SURFACE WARM SECTOR
IS CATEGORIZED BY LOW MID 60S TEMPS OVER LOW 60S DEW POINTS.
SOUTHERLY GUSTS HAVE STARTED TO SHOW UP IN RESPONSE TO THE
PRESSURE FALLS ACROSS CENTRAL IL...WITH GUSTS INTO THE SOUTHERN
FORECAST AREA.
WHILE WE HAVE NOT SEEN MUCH THUNDER THUS FAR...COULD FORESEE AN
UPTICK ACROSS CENTRAL IL DURING THE NEXT SEVERAL HOURS AS THE DRY
SLOT BEGINS TO MOVE IN AND LOW-LEVEL CAPE IS REALIZED AHEAD OF
THE BOUNDARY. VISIBLE SATELLITE IS INDICATING DEEPER CLOUDS
IMMEDIATELY AHEAD OF THAT LOW...COINCIDENT WITH THE STRONG MID-
LEVEL JET. CONVECTIVE ALLOWING GUIDANCE FROM 12Z OVERALL CONTINUES
TO INDICATE THE SOUTHEAST FORECAST AREA IS MOST FAVORED FOR SOME
OF THIS. IT LOOKS LIKE ANY SCATTERING MAY STRUGGLE TO REACH THIS
FAR NORTH...WHICH WOULD ENABLE AREAS TO GET FIRMLY INTO THE MID
60S AND INCREASE THAT LOW-LEVEL CAPE /AS WELL AS THE EFFECTIVENESS
OF THE MODEST TO HIGH LOW-LEVEL SHEAR/. STILL...A CHANCE FOR SOME
GUSTIER STORMS IMMEDIATELY AHEAD OF THE FRONT EXISTS...AND EVEN
POSSIBLY LOW-OPPED SUPERCELLS GIVEN THE DEEP LAYER SHEAR IN THE
SOUTHEAST CWA. WILL KEEP AN EYE ON THE SURFACE WIND FIELD AHEAD OF
THIS SECONDARY LOW AS SOME MINOR BACKING HAS BEEN NOTED ACROSS
CENTRAL IL. WHILE NO GUIDANCE IS INDICATING THIS TO CONTINUE OR TO
BACK FURTHER...COULD FORESEE THAT HAPPENING IF THE LOW DEEPENS
MORE RAPIDLY AND MORE WARMING OCCURS IN ADVANCE. OVERALL THAT
COULD INCREASE THE SMALL CONDITIONAL TORNADO THREAT THAT THESE
DYNAMIC EARLY COOL SEASON-ESQUE SYSTEMS CAN BRING.
IMMEDIATELY ALONG AND BEHIND THE SURFACE FRONT APPEARS A DECENT
SETUP FOR A SEVERAL HOUR WINDOW OF HIGHER WIND GUSTS. A STRONG
ISALLOBARIC COMPONENT WILL BE DEVELOPING DUE TO THE SURFACE LOW
PROJECTION TO RAPIDLY DEEPEN...AND LOW-LEVEL LAPSE RATES RAPIDLY
STEEPEN. THIS AREA WILL ALSO BE UNDER THE NOSE OF THE DRY
SLOT...OR STING...A SYNOPTIC AREA THAT CAN INDUCE HIGHER WINDS TO
BE REALIZED AT THE TOP OF THE MIXED LAYER. SO HAVE ADDED THE
POTENTIAL FOR 40 MPH GUSTS INTO THE EARLY EVE
FORECAST...GENERALLY ALONG AND EAST OF INTERSTATE 55 WHERE
PARAMETERS ARE OVERLAPPING.
MTF
//PREV DISCUSSION...
402 AM CDT
MAIN FORECAST CONCERNS THIS MORNING ARE FOCUSED ON ADDITIONAL HEAVY
RAINFALL AMOUNTS ACROSS THE CENTRAL/SOUTHERN PARTS OF THE CWA...AND
SOME POTENTIAL FOR A FEW STRONG/SEVERE THUNDERSTORMS THIS AFTERNOON
ACROSS THE SOUTHEAST.
SURFACE LOW PRESSURE WAS DEEPENING OVER THE UPPER MISSISSIPPI VALLEY
EARLY THIS MORNING...IN RESPONSE TO STRONG FORCING ASSOCIATED WITH
UPPER TROUGH PROPAGATING ACROSS THE CENTRAL CONUS. WITH DEEPENING
AND NORTHWARD MOVEMENT OF THE SURFACE LOW...WARM FRONT HAS DEVELOPED
NORTH ACROSS THE AREA OVERNIGHT WITH A VERY MILD/MOIST AIR MASS
SPREADING ACROSS THE FORECAST AREA. SEVERAL SMALLER MID-LEVEL SHORT
WAVES EMERGING AHEAD OF THE LARGER SCALE UPPER TROUGH IN SOUTHWEST
FLOW HAVE PRODUCED PERIODS OF MODERATE/LOCALLY HEAVY RAINFALL SINCE
LAST EVENING...WITH A COUPLE OF SWATHS OF 2+ INCH RAINFALL AMOUNTS
OVER THE SOUTHERN HALF OF THE CWA. THE EXCEPTION HAS BEEN THE FAR
SOUTHEAST CORNER...WHICH WAS SOUTH OF THE HEAVIER RAIN AXIS
OVERNIGHT. ADDITIONAL RAINFALL IS ON THE WAY...AS CURRENT SHORT WAVE
AND THEN STRONGER UPSTREAM WAVE CURRENTLY LIFTING NORTHEAST FROM THE
TX/OK PANHANDLE REGION TRACK TOWARD THE AREA. THESE IN COMBINATION
WITH LARGE SCALE ASCENT AND HEIGHT FALLS WITH THE APPROACHING UPPER
TROUGH SHOULD CONTINUE TO GENERATE CLUSTERS OF MODERATE/LOCALLY
HEAVY RAIN THROUGH THE DAY. MOST OF THE HIGH-RES CONVECTION ALLOWING
GUIDANCE...ARW/NMM/HRRR ETC...INDICATE THAT THE SOUTHEAST HALF OF
THE CWA WILL LIKELY SEE MORE FOCUSED RAINFALL AND EMBEDDED THUNDER
AFTER PERHAPS AN EARLY MORNING LULL. WITH THE UNSEASONABLY MOIST AIR
MASS AND STRONG/PERSISTENT FORCING...AM CONCERNED THAT AN ADDITIONAL
1-2 INCHES OF RAINFALL COULD CAUSE SOME LOCALIZED FLOODING AND RISES
ON SMALLER TRIBUTARIES AND CREEKS. HOWEVER...SINCE RAINFALL WILL BE
SPREAD OUT OVER 24 HOURS FOR THE MOST PART HAVE DECIDED TO HOLD OFF
ON A FLOOD WATCH. WILL HOWEVER ISSUE AN ESF/HYDROLOGIC OUTLOOK TO
ADDRESS RAINFALL AMOUNTS AND ANTICIPATED EFFECTS.
OTHER CONCERN IS FOR THE POSSIBILITY OF SOME STRONG/SEVERE
THUNDERSTORMS TO AFFECT SOUTHEAST PARTS OF THE CWA THIS AFTERNOON
AHEAD OF THE COLD FRONT. A STRONG MID-LEVEL JET STREAK IS EXPECTED
TO SPREAD ACROSS THE REGION THIS AFTERNOON WITH THE APPROACH OF THE
STRONGER SHORT WAVE NOW OVER THE PLAINS. COUPLED WITH 50 KT LOW
LEVEL JET STREAK AROUND 850 MB...0-6 KM BULK SHEAR WILL INCREASE TO
70-80 KT BY LATE AFTERNOON COINCIDENT WITH THE ADVANCING COLD FRONT.
WHILE SFC-BASED INSTABILITY MAY BE LACKING DUE TO MOIST FLOW/CLOUDS
THERE APPEARS TO BE SUFFICIENT WEAK ELEVATED CAPE MAINLY ACROSS OUR
SOUTHEAST COUNTIES TO SUPPORT SOME ORGANIZED THUNDERSTORMS AHEAD OF
THE FRONT. DAMAGING WIND GUSTS WOULD BE THE MOST LIKELY SEVERE
THREAT WITH QUICK MOVING STORMS AND PLENTY OF MOMENTUM JUST ABOVE
THE BOUNDARY LAYER...THOUGH A CONDITIONAL LOW PROBABILITY TORNADO
THREAT EXISTS AS WELL WITH 0-1 KM BULK SHEAR NEAR 40 KT AND MOIST
LOW LEVELS. SPC HAS OUTLOOKED OUR SOUTHEAST COUNTIES FOR A SLGT RISK
OF SEVERE THIS AFTERNOON. THE COLD FRONT WILL PUSH EAST OF THE AREA
BY EARLY THIS EVENING... THOUGH SCATTERED SHOWERS MAY LINGER BEHIND
THE FRONT FOR A TIME AS STRONG UPPER TROUGH AXIS LAGS THE SURFACE
BOUNDARY. PRECIP SHOULD END FROM WEST TO EAST...ENDING BY OR SHORTLY
AFTER MIDNIGHT IN NORTHWEST INDIANA.
COOLER WEATHER THEN RETURNS LATER TONIGHT AND FRIDAY...WITH ANOTHER
STRONGER SHORT WAVE DIGGING ACROSS THE AREA FRIDAY NIGHT/EARLY
SATURDAY TO BRING A REINFORCING PUSH OF COLDER AIR FOR THE WEEKEND.
INSTABILITY STRATOCU AND A FEW SHOWERS/SPRINKLES ARE POSSIBLE WITH
THIS STRONGER WAVE FRIDAY NIGHT/SATURDAY...BEFORE HIGH PRESSURE
BUILDS IN FROM THE WEST SATURDAY NIGHT. AFTER 60S TODAY...EXPECT
HIGHS IN THE UPPER 40S/LOWER 50S FOR THE WEEKEND. LOWS SUNDAY
MORNING WILL LIKELY DIP INTO THE 20S WEST OF CHICAGO...WHERE
CLEARING SKIES AND THE SURFACE RIDGE AXIS WILL SUPPORT STRONG
RADIATIONAL COOLING. ANOTHER LOW PRESSURE SYSTEM IS PROGGED TO LIFT
ACROSS THE UPPER MIDWEST EARLY NEXT WEEK...BRINGING SOUTH WINDS AND
MILDER TEMPS AT LEAST WELL INTO THE 50S. THE CHANCE OF RAIN WILL
INCREASE AGAIN MONDAY NIGHT THROUGH MID-WEEK AS GUIDANCE CURRENTLY
INDICATES ANOTHER SURFACE WAVE RIPPLING UP THE APPROACHING COLD
FRONT.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* PERIODS OF IFR CIGS THROUGH EARLY EVENING.
* PERSISTENT RAIN RETURNING FOR A PERIOD THIS AFTERNOON...WITH
LOWER VIS IN THE HEAVIER RAIN.
* ISOL/SCT THUNDERSTORMS STILL POSSIBLE THIS AFTERNOON...MAINLY
SOUTH OF THE TERMINALS.
* PERIOD OF VERY GUSTY WEST-NORTHWESTERLY WINDS BY LATE
AFTERNOON/EARLY THIS EVENING IN THE WAKE OF THE COLD FRONT.
KJB
//DISCUSSION...UPDATED 18Z...
THE WEATHER WILL CONTINUE TO BE MESSY THIS AFTERNOON AND INTO THE
EVENING ACROSS THE REGION AS A POTENT STORM SYSTEM CONTINUES TO
STRENGTHEN AS IT MOVES FROM WISCONSIN TO LOWER MICHIGAN BY THIS
EVENING.
ASIDE FROM A FEW BRIEF BREAKS IN THE LOW CLOUDS...CIGS CONTINUE TO
RESIDE BETWEEN 800 TO 1000 FEET ACROSS THE AIRSPACE EARLY THIS
AFTERNOON...AND THIS WILL CONTINUE TO BE THE CASE THROUGH THE DAY.
MORE PERSISTENT HEAVIER RAIN WILL CONTINUE TO OVERSPREAD THE AREA
THIS AFTERNOON AHEAD OF AN APPROACHING COLD FRONT. VISIBILITIES IN
THE HEAVIER RAIN COULD FALL TO 2 TO 3 MILES FOR A PERIOD THIS
AFTERNOON. CIGS AND VIS SHOULD IMPROVE AND RAIN WILL END BY MID TO
LATE EVENING AS THE SYSTEM MOVES NORTHEAST ACROSS NORTHERN LOWER
MICHIGAN.
WINDS WILL REMAIN AROUND 7 TO 10 KT OUT OF THE SOUTH AHEAD OF THIS
COLD FRONT. HOWEVER...THIS COLD FRONT WILL PUSH ACROSS THE KRFD AREA
AROUND 20 UTC...AND AROUND 2230 TO 23 UTC AT THE EASTERN TAF SITES.
ONCE THIS FRONT PUSHES THROUGH...EXPECT A RAPID WIND SHIFT OUT OF
THE WEST-NORTHWEST. IT ALSO APPEARS THAT THERE COULD BE A PERIOD OF
SOME FAIRLY STRONG WINDS AS WELL IN THE WAKE OF THIS FRONT EARLY
THIS EVENING. WIND GUSTS COULD APPROACH OR EVEN EXCEED 30 KT FOR A
SHORT ONE OR TWO HOUR PERIOD THIS EVENING AFTER 23 UTC. THE WINDS
WILL REMAIN OUT OF THE WEST INTO FRIDAY...BUT WIND GUSTS WILL ABATE
SOME.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM TO HIGH CONFIDENCE WITH CEILINGS/TRENDS.
* LOW CONFIDENCE WITH THUNDERSTORMS AT THE TERMINALS.
* MEDIUM TO HIGH CONFIDENCE WITH GUSTY WINDS THIS EVENING.
KJB
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...CHANCE OF SHOWERS...OTHERWISE VFR.
SATURDAY...SLIGHT CHANCE OF SHOWERS...OTHERWISE VFR.
SUNDAY...VFR.
MONDAY...CHANCE OF SHOWERS LATE...OTHERWISE VFR.
TUESDAY...CHANCE OF SHOWERS...OTHERWISE VFR.
WEDNESDAY...CHANCE OF SHOWERS...OTHERWISE VFR.
RODRIGUEZ
&&
.MARINE...
702 AM CDT
STRONGER WINDS EXPECTED OVER THE LAKE AND THE NEARSHORE WATERS
TONIGHT...WITH GALES LIKELY ACROSS THE ENTIRE LAKE AND THE INDIANA
NEARSHORE WATERS.
A TROUGH OF LOW PRESSURE OVER THE UPPER MIDWEST WILL CONTINUE
LIFTING TO THE NORTHEAST ACROSS THE CENTRAL GREAT LAKES REGION
TODAY WHILE DEEPENING....WITH SOUTHERLY WINDS LIKELY ACROSS THE
LAKE. ALTHOUGH AS THIS LOW CONTINUES NORTHEAST INTO SOUTHEAST
ONTARIO AND SOUTHERN QUEBEC TONIGHT INTO EARLY FRIDAY...IT WILL
FURTHER DEEPEN WITH A PERIOD OF STRONGER WINDS DEVELOPING ACROSS
THE ENTIRE LAKE. EXPECT GALES TO 35 KT TO DEVELOP OVER THE
NORTHERN PORTIONS...AND THEN TO 40 KT OVER THE SOUTHERN HALF
TONIGHT BEFORE DIMINISHING ONCE AGAIN EARLY FRIDAY MORNING. WINDS
WILL REMAIN SOMEWHAT STRONGER INTO SATURDAY AS A TROUGH OF LOW
PRESSURE WILL LINGER ACROSS THE EASTERN GREAT LAKES. THIS TROUGH
WILL SHIFT EAST SATURDAY NIGHT...WHILE HIGH PRESSURE BUILDS EAST
ACROSS THE CENTRAL PLAINS AND THEN INTO THE WESTERN GREAT LAKES.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 9 PM THURSDAY.
GALE WARNING...LMZ743-LMZ744-LMZ745...9 PM THURSDAY TO 4 AM
FRIDAY.
GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...9 PM THURSDAY TO 9 AM
FRIDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...4 PM THURSDAY TO
10 AM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1227 PM CDT Thu Oct 31 2013
.DISCUSSION...
ISSUED 1027 AM CDT Thu Oct 31 2013
Widespread showers continuing over all of the CWA this morning,
although a narrow dry slot in the St Louis area is trying to move
in. Latest surface observations show the cold front along the
Illinois/Iowa border extending southwest into southeast Kansas.
Latest HRRR shows the front near the I-57 corridor by 00Z, with a
narrow line of convection firing along it early this afternoon.
Southeast half of the forecast area remains in the slight risk for
severe weather this afternoon, but areas along/east of I-57 may
see the best shot of any damaging winds. Temperatures across the
northwest CWA will be falling later this afternoon behind the
front, but should still reach the mid to upper 60s in most areas
ahead of it.
Updated zones/grids have been sent. These mainly adjusted the
hourly temperature trends. Also did some tweaks to the rain trends
this evening behind the front.
Geelhart
&&
.AVIATION...
ISSUED 1226 PM CDT Thu Oct 31 2013
Main concern with the TAF`s will be with the period through about
02Z. Cold front currently located from near KGBG-KJEF will be
pushing eastward through the afternoon. Besides the widespread
showers, a narrow band of convection has been increasing
immediately along the front from southeast of KUIN into the
western St. Louis metro. This will be most likely to affect areas
from KSPI-KCMI through mid to late afternoon. Ceilings have
largely been around 500 feet or so, but visible satellite imagery
showing some clouds across western Illinois briefly poking above
3000 feet. Think the more likely period for any substantial VFR
conditions to arrive will be by mid to late evening. Highest winds
through this afternoon will be near KCMI with gusts of 25 knots or
so, with gusts briefly subsiding over central Illinois with the
frontal passage. However, additional gusts of 15-20 knots likely
for a few hours following the front.
Geelhart
&&
.PREV DISCUSSION...
ISSUED 237 AM CDT Thu Oct 31 2013
SHORT TERM...Today through Saturday
Periods of rain will persist across central Illinois today, as a
moist southwesterly flow continues ahead of a slowly approaching
cold front. Boundary will reach the I-55 corridor by around
midday, then will push into western Indiana by early evening. Main
question of the day will be if any severe weather will develop
ahead of the front this afternoon/evening. Forecast soundings
continue to show a saturated and rather stable warm sector:
however, latest run of the NAM suggests a weak surface wave riding
northeastward along the boundary may pull a slightly more unstable
airmass into east-central and southeast Illinois later today. This
added instability will combine with impressive 0-6km shear values
of 80 to 90kt to potentially produce a few strong to severe
storms. 4km WRF-NMM hints at a possible narrow squall line ahead of
the front between 2 PM and 8 PM, mainly along/east of I-57. As a
result, the Storm Prediction Center (SPC) has outlooked much of
east-central and southeast Illinois for a slight risk of severe.
Any storms that develop will push into Indiana after 8 PM:
however, scattered showers will persist further west through the
evening hours. Total rainfall today into this evening will
generally range from 1 to 1.50, but will be higher within stronger
storms.
Partly to mostly sunny skies and cooler conditions can be expected
on Friday in the wake of the departing cold front. High
temperatures will be several degrees cooler than today, ranging
from the middle 50s far north to the lower 60s south of I-70.
Clouds will be on the increase Friday afternoon/evening, as a
short-wave digs southeastward out of the Northern Plains. This
feature will carve a trough across the Great Lakes Friday night
into Saturday. Models continue to produce a few light showers
beneath this feature, mainly across northern Illinois into
north-central Indiana. As a result, will maintain a cool/dry
forecast across central Illinois through Saturday.
LONG TERM...Sunday through Wednesday
High pressure will provide continued cool/dry weather for Sunday
and Monday before the next system begins to approach from the west
by Tuesday. Significant model spread exists concerning speed of
system, mainly due to varying strengths of blocking upper ridge
progged to develop in the southeast U.S. ECMWF is indicating an
unseasonably strong 594dm 500mb high building over the Carolinas
early next week, which slows the eastward progression of an upper
wave and associated cold front across the central CONUS. This
solution would bring an extended period of rain chances to central
Illinois from Tuesday through Thursday. Meanwhile, both the GFS
and GEM are slightly weaker with the Carolinas high and thus bring
the Plains system eastward through the region a bit faster. Rain
chances with this solution would generally be confined to just
Tuesday and Wednesday. Whichever solution eventually pans out, it
appears another period of beneficial rainfall is likely early next
week. Have included PoPs for Tuesday and Wednesday, hitting rain
chances hardest across the entire area on Wednesday. After a
chilly weekend, temps will return to near normal in the upper
50s/lower 60s next week.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1241 PM CDT THU OCT 31 2013
.SHORT TERM /TODAY/...
ISSUED AT 335 AM CDT THU OCT 31 2013
LOW PRESSURE HAS MOVED INTO NERN IA NOW WITH THE COLD FRONT ALONG
THE EAST EDGE OF THE CWA. COLD FRONT WILL CONTINUE TO MAKE
PROGRESS...HOWEVER UPPER LOW NOT LIFTING THROUGH THE OK PANHANDLE
WILL RESULT IN AN EXPANSION OF THE RAIN WESTWARD AGAIN. HRRR HAD A
PRETTY GOOD HANDLE ON IT. ALTHOUGH THE FARTHEST WEST OF THE
MODELS...IT DOES NOT LOOK ALL THAT BAD GIVEN RADAR TRENDS.
EXPANSION HAS BEEN PUT INTO THE GRIDS FOR THIS MORNING WITH RAIN
GRADUALLY ENDING FROM THE WEST THIS AFTERNOON. TEMPS WILL NOT RISE
IN THE SOUTHEAST TODAY WITH MODEST RISES IN THE NORTHWEST. WINDS
WILL BECOME A SOMEWHAT GUSTY FOR A WHILE TODAY...BUT NOT MUCH HIGHER
THAN 20 MPH OR SO.
.LONG TERM /TONIGHT THROUGH WEDNESDAY/...
ISSUED AT 335 AM CDT THU OCT 31 2013
SYSTEM WILL DEPART TO THE EAST TONIGHT WITH SUBSIDENCE...CLEARING
AND COOLER TEMPERATURES. HOWEVER...ANOTHER SHORTWAVE WILL RAPIDLY
ADVANCE ON THE STATE FROM THE NORTHWEST ON FRIDAY. MOISTURE WILL
BE GENERALLY LACKING WITH THIS SYSTEM...HOWEVER DECENT MID LEVEL
FORCING AND STEEP LAPSE RATES WILL LEAD TO ISOLD/SCT SHOWER
DEVELOPMENT ACROSS NORTHERN IOWA BY AFTERNOON. FARTHER SOUTH...
SOUNDINGS ARE DRIER WITH LESS THREAT OF PCPN. WINDS WILL BE QUITE
STRONG ON FRIDAY AS WELL WITH DECENT PRESSURE GRADIENT AND NEARLY
UNIDIRECTIONAL FLOW THROUGH A GOOD DEPTH OF THE ATMOSPHERE...AND
HELPED ALONG WITH NEARLY ADIABATIC LAPSE RATES IN THE LOW LEVELS.
QUITE WEATHER IS EXPECTED THIS WEEKEND AS HIGH PRESSURE MOVES
ACROSS THE STATE. SOUTH WINDS WILL INCREASE QUICKLY ON SUNDAY ON
BACKSIDE OF HIGH AS LARGE WESTERN TROF DEVELOPS. GFS AND EURO
COMING CLOSER ON SOLUTIONS AND INDICATE A PROLONGED PERIOD OF
RAINFALL CHANCES FROM LATE SUNDAY NIGHT INTO WEDNESDAY. IOWA WILL
BE ON WESTERN EDGE OF WARM CONVEYOR BELT FROM GULF OF MEXICO WITH
DECENT RAINS EXPECTED...ESPECIALLY MOVING TO THE EAST ACROSS THE
STATE. TEMPERATURES MAY COOL ENOUGH BEHIND A SLOWLY MOVING COLD
FRONT FOR SOME TRANSITION TO SNOW BY TUESDAY NIGHT IN THE FAR
NORTHWEST.
&&
.AVIATION...31/18Z
ISSUED AT 1241 PM CDT THU OCT 31 2013
AN UPPER LEVEL DISTURBANCE OVER KS WILL LIFT ACROSS SE IA. THIS
WILL KEEP A FEW SHOWERS GOING THROUGH 21Z. AS THE NORTHERN PLAINS
UPPER LEVEL TROUGH SHIFTS EAST THROUGH EARLY EVENING...CIGS WILL
LIFT. ANOTHER UPPER LEVEL WAVE SLIDES DOWN ACROSS THE NORTHERN
PLAINS IN TO NORTHERN IA INCREASING CLOUDS AFT 01/06Z. SFC FLOW
WILL BECOME WESTERLY AND INCREASE AFT 01/12Z IN RESPONSE TO THAT
NEXT WAVE.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...MS OCT 13
LONG TERM...COGIL
AVIATION...FAB
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
353 PM EDT THU OCT 31 2013
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/HYDRO/MARINE
.SYNOPSIS...
ISSUED AT 336 PM EDT THU OCT 31 2013
STRONG LOW PRESSURE WILL WILL BRING RAIN THIS EVENING AND HIGH
WINDS AFTER MIDNIGHT. SCATTERED POWER OUTAGES ARE EXPECTED AS
WINDS GUST OVER 50 MPH AT TIMES. THE WEATHER WILL COME DOWN FRIDAY
MORNING BUT SCATTERED SHOWERS WILL CONTINUE INTO SATURDAY. FAIR
AND COOL WEATHER IS EXPECTED FOR SUNDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 336 PM EDT THU OCT 31 2013
FORECAST ISSUES ARE FOR HIGH WIND LATE TONIGHT...AND THUNDER/RAIN
THIS EVENING.
WENT WITH A WIND ADVISORY FOR LATE TONIGHT AS THE LOW DEEPENS AND
COLD AIR ADVECTION BEGINS AFTER MIDNIGHT SOME STRONG WINDS COULD
MIX DOWN. BOTH THE NAM AND GFS SHOW 50 KNOTS OF WIND CLOSE TO OR
IN THE MIXING LAYER. THE 12Z EURO IS A BIT WEAKER AND FASTER WITH
THE SFC LOW. WENT WITH A HIGH WIND ADVISORY...ALTHOUGH THERE IS A
CHANCE OF SOME SPOTS GUSTING TO 50 KNOTS ACROSS THE EASTERN
FORECAST AREA AROUND 09Z.
BEFORE THEN...WILL BE WATCHING THE RADAR EVOLUTION OF THE PRECIP
CURRENTLY ACROSS CENTRAL ILLINOIS. DRY SLOT CURRENTLY OVER WESTERN
LOWER MICHIGAN...BUT STILL SEEING DRIZZLE AND SOLID CLOUD
COVER...SO LITTLE IN THE WAY OF SFC INSTABILITY EXPECTED LATE THIS
AFTERNOON/EVENING. A WEAK NCFR COULD STILL FORM AS HINTED AT BY A
FEW RUNS OF THE HRRR AND RADAR ACROSS CENTRAL ILLINOIS. THIS COULD
BRING A BRIEF BURST OF RAIN AND WIND THIS EVENING...OTHERWISE IT
SHOULD JUST BE A SOGGY AND MILD TIME FOR TRICK OT TREATING. THE
SYNOPTIC WIND THREAT ARRIVES LATER.
NO REAL IMPACTS EXPECTED AFTER FRIDAY MORNING. SOME SNOWFLAKES ARE
POSSIBLE SATURDAY EVENING AS 850 MB TEMPS FALL BLO MINUS 6C AND
LAKE EFFECT CONTINUES...BUT THESE SHOULD NOT AMOUNT TO MUCH.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 336 PM EDT THU OCT 31 2013
FAIR WEATHER WITH SEASONABLY COOL TEMPERATURES IS EXPECTED SUNDAY
WITH HIGH PRESSURE IN PLACE. STRONG SOUTHERLY RETURN FLOW WARM AIR
ADVECTION WILL DEVELOP EARLY TO MID NEXT WEEK AS THE RIDGE MOVES
EAST. WARM AIR ADVECTION SHOWERS MAY DEVELOP AS EARLY AS LATE MONDAY
NIGHT AND TUESDAY.
HOWEVER THE BETTER CHANCE FOR RAIN WILL HOLD OFF UNTIL WEDNESDAY
THROUGH THURSDAY AS THE NEXT LOW PRESSURE SYSTEM MOVES THROUGH THE
GREAT LAKES REGION. MAX TEMPS MONDAY THROUGH WEDNESDAY WILL REACH
THE 50S BEFORE COOLING TO THE 40S BEHIND THAT SYSTEM FOR LATE NEXT
WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY)
ISSUED AT 1230 PM EDT THU OCT 31 2013
MAINLY IFR CONDITIONS ARE ANTICIPATED AT ALL THE TERMINALS THIS
AFTERNOON AND EVENING DUE TO LOW CLOUDS AND RAIN. POCKETS OF LIFR
ARE POSSIBLE. WE CANNOT COMPLETELY RULE OUT AN ISOLATED THUNDERSTORM
LATE THIS AFTERNOON OR EARLY EVENING BUT THERE IS NOT ENOUGH
POTENTIAL IN THIS TO WARRANT INCLUSION IN ANY OF THE TERMINAL
FORECASTS.
WINDY CONDITIONS WILL DEVELOP THIS EVENING AND OVERNIGHT AS WINDS
VEER TO THE WEST AND INCREASE TO 20 TO 30 KTS WITH GUSTS TO 35 TO 40
KTS POSSIBLE... MAINLY AT KMKG. CONDITIONS LATE TONIGHT THROUGH 18Z
FRIDAY SHOULD BE MAINLY MVFR DUE TO LINGERING LOW CLOUDS AND LIGHTER
POST FRONTAL SHOWERS.
&&
.MARINE...
ISSUED AT 336 PM EDT THU OCT 31 2013
NO CHANGES TO THE SMALL CRAFT ADVISORY OR GALE WARNING. WINDS
WILL DIMINISH ON FRIDAY MORNING AND THE GALE WARNING WILL BE
REPLACED WITH ANOTHER SMALL CRAFT ADVISORY AT THAT TIME.
&&
.HYDROLOGY...
ISSUED AT 336 PM EDT THU OCT 31 2013
SOME RAIN TOTALS OVER 3 INCHES IN VAN BUREN COUNTY AND EXPECT
ANOTHER HALF INCH TO INCH BEFORE THE HEAVY RAIN ENDS TONIGHT. WE
WILL CONTINUE TO SEE SHARP RISES ON SOME STREAMS AND CREEKS WITH
RISES ON MANY OF THE MAINSTEM RIVERS INTO EARLY NEXT WEEK. AFTER A
BREAK...ANOTHER ROUND OF RAIN IS EXPECTED BY WEDNESDAY OF NEXT
WEEK.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WIND ADVISORY FROM 2 AM TO 8 AM EDT FRIDAY FOR MIZ037>040-
043>046-050>052-056>059-064>067-071>074.
LM...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR LMZ844>849.
GALE WARNING FROM 10 PM THIS EVENING TO 10 AM EDT FRIDAY FOR
LMZ844>849.
&&
$$
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...LAURENS
AVIATION...LAURENS
HYDROLOGY...OSTUNO
MARINE...OSTUNO
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1246 PM CDT THU OCT 31 2013
.UPDATE...
UPDATED PRODUCTS WITH NEW TORNADO WATCH NOW IN EFFECT FOR CENTRAL
AND EAST MS THROUGH 7PM THIS EVENING. UPDATED RAINFALL AXIS TIMING
AS IT SWEEPS ACROSS THE REGION THIS EARLY AFTN THROUGH EARLY FRIDAY
MORNING. IN ADDITION, NEW THOUGHTS ON POSSIBLE STRONG/SEVERE
CONVECTIVE EVOLUTION THIS AFTERNOON IN DISCUSSION BELOW.
.DISCUSSION...
LATEST RADAR TRENDS HAVE SEEN AN UPTICK IN STRONGER LEWP
REFLECTIVITY CORES EMBEDDED WITHIN THE HEAVY RAIN AXIS ACROSS WEST
MS AND NORTHEAST LA. MID-ALTITUDE RADIAL CONVERGENCE HAS BEEN ON THE
INCREASE WITH THESE LEWP FEATURES AND WITH 0-1 SRH 400-500 M2/S2 AND
PLUS SOME INCREASED SBCAPE NEAR 500 J/KG WITH SLIGHT BOUNDARY
BUOYANCY RECOVERY...THE TORNADO RISK AND STRAIGHTLINE WIND RISK WILL
BE ON THE INCREASE THROUGH THE EARLY AFTN THROUGH EARLY EVENING FOR
THE WATCH AREA.
LATEST RUC ANALYSIS DEPICTS ENHANCED SURFACE CONVERGENCE BAND WHERE
STRONGER CONVECTION IS CURRENTLY LOCATED ACROSS CENTRAL AND SOUTH
LOUISIANA. THE RUC BRINGS THIS ENHANCED CONVERGENCE BAND ACROSS
SOUTH AND CENTRAL MS THROUGH 6PM THAT WOULD BE INDICATIVE OF DEEPER
CORES TAKING ADVANTAGE OF THE HIGHLY SHEARED ENVIRONMENT. QUICK SPIN
UP VORTICIES HAVE BEEN SEEN SEEN ON FORT POLK RADAR OVER THE PAST
FEW HOURS AND THIS POSSIBILITY WILL PERSIST ACROSS THE WATCH AREA
THROUGH 7PM TONIGHT.
THE WORST OF THE WEATHER WILL CLEAR WEST MISSISSIPPI AND NORTHEAST
LOUISIANA MID TO LATE AFTERNOON...THE JACKSON METRO/TRACE CORRIDOR
BY LATE AFTERNOON TO MID EVENING AND THEN EAST MISSISSIPPI BY
MIDNIGHT. HAVE UPDATED THE WEATHER GRIDS WITH THIS LATEST TIMING.
NEW GRAPHICS WILL BE POSTED SHORTLY WITH UPDATED TEXT PRODUCTS OUT.
/ALLEN/
&&
.AVIATION...MAINLY MVFR CONDITIONS ANTICIPATED THROUGH MUCH OF THE
DAY ACROSS THE AERODROME AS RAIN AND EMBEDDED THUNDERSTORMS
GRADUALLY PUSH INTO THE HEART OF THE REGION. THUNDERSTORMS THROUGH
EARLY THIS EVENING WILL BE MORE NUMEROUS SOUTH OF INTERSTATE TWENTY
AND A FEW OF THESE COULD CONTAIN VERY GUSTY WINDS. AWAY FROM STORMS
ANTICIPATE GUSTY SOUTH WINDS OVER 20 KTS AT TIMES. THE STRONGEST
WINDS WILL BE THROUGH EARLY AFTERNOON AT GLH/GWO. POCKETS OF IFR
CONDITIONS WILL BE POSSIBLE IN ALL AREAS FOR ONE TO TWO HOURS AT A
TIME DURING THE DAY AS THE POCKETS OF HEAVIEST PRECIPITATION MOVE
OVER THE STATION.
PRECIPITATION SHOULD BE GRADUALLY CLEARING TO THE EAST THROUGH THE
NIGHT TONIGHT...ALTHOUGH MVFR TO PATCHY IFR CONDITIONS MAY LINGER IN
SOME FASHION UNTIL MORNING. THE LATTER WILL ESPECIALLY BE THE CASE
ACROSS EASTERN PORTIONS OF MS. /BB/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 53 74 46 71 / 61 11 0 5
MERIDIAN 56 74 43 70 / 94 17 0 6
VICKSBURG 50 74 46 71 / 37 8 0 5
HATTIESBURG 63 78 48 73 / 100 31 0 9
NATCHEZ 52 73 49 71 / 39 9 0 5
GREENVILLE 49 73 47 69 / 25 7 0 4
GREENWOOD 49 73 47 68 / 37 8 0 5
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...FLASH FLOOD WATCH UNTIL MIDNIGHT CDT TONIGHT FOR MSZ018-019-
025>045-047>050-053>055-059>062.
WIND ADVISORY UNTIL 5 PM CDT THIS AFTERNOON FOR MSZ018-019-025-
034-035-040-041.
LA...FLASH FLOOD WATCH UNTIL MIDNIGHT CDT TONIGHT FOR LAZ007>009-015-
016-023>026.
WIND ADVISORY UNTIL 5 PM CDT THIS AFTERNOON FOR LAZ007>009-015-
016-023>026.
AR...FLASH FLOOD WATCH UNTIL MIDNIGHT CDT TONIGHT FOR ARZ074-075.
WIND ADVISORY UNTIL 5 PM CDT THIS AFTERNOON FOR ARZ074-075.
&&
$$
/
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
351 PM CDT Thu Oct 31 2013
.SHORT TERM: (Through Tonight)
Issued at 221 PM CDT Thu Oct 31 2013
Focus for tonight will be pops as the upper trof moves thru the
area.
Upper trof just starting to enter far nwrn MO with dry slot
spreading over much of the area. Vort max rounding the base of the
trof now will help eject the trof ewd along with the precip. Have
trended pops this eve twd the 4km local WRF and the HRRR which are
in fairly good agreement along with much of the other guidance as
well. These solns suggest a line of TSRA across far ern portions of
the CWA with some stratiform precip behind that, but exiting the
area quickly. The CWA shud be dry by 03z if not before.
With clouds clearing out of the area tonight, have trended twd the
cooler guidance. That said, do not anticipate temps dropping too
much tonight with mixing persisting thru the night and with no
substantial cooler or drier air advecting into the region.
Tilly
.LONG TERM: (Friday through Next Thursday)
Issued at 321 PM CDT Thu Oct 31 2013
Period begins with focus on temps thru the weekend.
With ample clouds expected across much of the area on Fri and with
the sfc ridge building into the area on Sat, have trended twd the
cooler guidance thru the weekend. Warm up shud begin on Sun as the
sfc ridge starts to retreat and as the thermal ridge starts moving
nwd into the area.
For the extd, focus turns to pops late Mon thru Wed. Mdls have
come into better agreement with trof timing and phasing. Have
lowered pops on Mon and on Thurs with better agreement among mdls.
Increased pops between these times where mdls were in better
agreement regarding precip. Some uncertainty still remains and
will continue to adjust as needed.
Tilly
&&
.AVIATION: (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1225 PM CDT Thu Oct 31 2013
Complex weather scenario for this afternoon and early evening.
Line of showers has developed and has become attm the effective
boundary as winds veer sharply to the west concurrent with a drop
in temps and dewpoints. This line is approaching the St. Louis
metro area from the west/southwest as of 1700 UTC. However...area
of low pressure may develop to the southwest and help keep the
synoptic cold front back until around 2100 UTC. Thus...have a
TEMPO for brief gusty winds out of the west at the metro TAF sites
before prevailing winds become out of the SSW until actual fropa.
Kept VCTS mention at these sites too for this afternoon as there
may be just enough instability to produce some
thunder/lightning. IFR ceilings will also be possible at the metro
sites post-frontal and thus have a tempo in to account for this
possibility. At KCOU and KUIN...believe northwest winds will hold
through the valid TAF period with main concerns at these sites
being possible IFR ceilings and post- frontal shra. Both of these
sites should experience at least some IFR ceilings through late
this afternoon before scattering out. Skies should become mostly
clear overnight tonight with some diurnal cu with bases around
3000 feet likely tomorrow and west/northwest winds around 10-15
knots with some gusts around 20 knots.
Specifics for KSTL:
Complex weather scenario for this afternoon and early evening.
Line of showers has developed and has become attm the effective
boundary as winds veer sharply to the west concurrent with a drop
in temps and dewpoints. This line is approaching the St. Louis
metro area from the west/southwest as of 1700 UTC. However...area
of low pressure may develop to the southwest and help keep the
actual synoptic cold front back until around 2100 UTC.
Thus...have a TEMPO for brief gusty winds out of the west at the
metro TAF sites before prevailing winds become out of the SSW
until actual fropa. Kept VCTS mention at these sites too for this
afternoon as there may be just enough instability to produce some
thunder/lightning. IFR ceilings are possible after fropa so have a
tempo to account for this. Skies should become mostly clear
overnight tonight with some diurnal cu with bases around 3000 feet
likely tomorrow and west/northwest winds around 10-15 knots with
some gusts around 20 knots.
Gosselin
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 44 61 42 55 / 60 0 5 0
Quincy 39 56 37 51 / 20 5 10 0
Columbia 41 60 37 53 / 10 0 0 0
Jefferson City 42 62 37 54 / 10 0 0 0
Salem 44 61 41 54 / 80 0 10 0
Farmington 43 63 37 54 / 50 0 0 0
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
222 PM CDT Thu Oct 31 2013
.SHORT TERM: (Through Tonight)
Issued at 221 PM CDT Thu Oct 31 2013
Focus for tonight will be pops as the upper trof moves thru the
area.
Upper trof just starting to enter far nwrn MO with dry slot
spreading over much of the area. Vort max rounding the base of the
trof now will help eject the trof ewd along with the precip. Have
trended pops this eve twd the 4km local WRF and the HRRR which are
in fairly good agreement along with much of the other guidance as
well. These solns suggest a line of TSRA across far ern portions of
the CWA with some stratiform precip behind that, but exiting the
area quickly. The CWA shud be dry by 03z if not before.
With clouds clearing out of the area tonight, have trended twd the
cooler guidance. That said, do not anticipate temps dropping too
much tonight with mixing persisting thru the night and with no
substantial cooler or drier air advecting into the region.
Tilly
.LONG TERM: (Tonight through Wednesday)
Issued at 323 AM CDT Thu Oct 31 2013
A period of quiet weather will follow today`s activity. Expecting
seasonable temperatures in the upper 50s to lower 60s and dry
conditions Friday. The upper longwave pattern will amplify overhead
by Saturday morning with the Midwest being in northwest flow. This
will cause a cool high pressure system to build across the area
Saturday into Sunday. As a result, temperatures will fall below
normal with lows in the mid 30s to near 40 and highs in the low to
mid 50s Saturday rising to the mid 50s to near 60 on Sunday. The
next trof will amplify over the Rockies on Monday, and the flow
aloft will turn back to the southwest. Medium range models show a
trend for increasing clouds Monday as well as increasing chances for
precipitation. By Tuesday the axis of the low level jet will be
right over Missouri with a strong baroclinic zone stretching from
the southeast Plains in to eastern Kansas, northwest Missouri, and
Iowa. Models generate a wave of low pressure on the baroclinic zone
over Oklahoma Tuesday night and eject it northeast along the
baroclinic zone into Wednesday. Guidance has the cold front
associated with this system drifting into east central Missouri by
18Z Wednesday. Temperatures will be highly dependent upon clouds
and precip Monday through Wednesday, but it looks like temperatures
should be near or a few degrees below normal with an increasing
chance for rain, especially Tuesday and Wednesday.
Carney
&&
.AVIATION: (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1225 PM CDT Thu Oct 31 2013
Complex weather scenario for this afternoon and early evening.
Line of showers has developed and has become attm the effective
boundary as winds veer sharply to the west concurrent with a drop
in temps and dewpoints. This line is approaching the St. Louis
metro area from the west/southwest as of 1700 UTC. However...area
of low pressure may develop to the southwest and help keep the
synoptic cold front back until around 2100 UTC. Thus...have a
TEMPO for brief gusty winds out of the west at the metro TAF sites
before prevailing winds become out of the SSW until actual fropa.
Kept VCTS mention at these sites too for this afternoon as there
may be just enough instability to produce some
thunder/lightning. IFR ceilings will also be possible at the metro
sites post-frontal and thus have a tempo in to account for this
possibility. At KCOU and KUIN...believe northwest winds will hold
through the valid TAF period with main concerns at these sites
being possible IFR ceilings and post- frontal shra. Both of these
sites should experience at least some IFR ceilings through late
this afternoon before scattering out. Skies should become mostly
clear overnight tonight with some diurnal cu with bases around
3000 feet likely tomorrow and west/northwest winds around 10-15
knots with some gusts around 20 knots.
Specifics for KSTL:
Complex weather scenario for this afternoon and early evening.
Line of showers has developed and has become attm the effective
boundary as winds veer sharply to the west concurrent with a drop
in temps and dewpoints. This line is approaching the St. Louis
metro area from the west/southwest as of 1700 UTC. However...area
of low pressure may develop to the southwest and help keep the
actual synoptic cold front back until around 2100 UTC.
Thus...have a TEMPO for brief gusty winds out of the west at the
metro TAF sites before prevailing winds become out of the SSW
until actual fropa. Kept VCTS mention at these sites too for this
afternoon as there may be just enough instability to produce some
thunder/lightning. IFR ceilings are possible after fropa so have a
tempo to account for this. Skies should become mostly clear
overnight tonight with some diurnal cu with bases around 3000 feet
likely tomorrow and west/northwest winds around 10-15 knots with
some gusts around 20 knots.
Gosselin
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 44 61 42 55 / 60 0 5 0
Quincy 39 56 37 51 / 20 5 10 0
Columbia 41 60 37 53 / 10 0 0 0
Jefferson City 42 62 37 54 / 10 0 0 0
Salem 44 61 41 54 / 80 0 10 0
Farmington 43 63 37 54 / 50 0 0 0
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1231 PM CDT THU OCT 31 2013
.AVIATION...
18Z TAFS FOR KOMA...KLNK AND KOFK.
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. THE HIGH LEVEL
CLOUDS HAVE MOVED OUT OF KOFK AND WILL SOON MOVE OUT OF KOMA/KLNK AS
WELL. NORTHWEST WINDS WILL INCREASE THIS AFTERNOON WITH SOME GUSTS
POSSIBLE AT KOFK. THE CLOUDS WILL AGAIN INCREASE THIS EVENING AHEAD
OF ANOTHER WEAK SYSTEM CURRENTLY OVER MT. THIS MID AND HIGH LEVEL
CLOUDS WILL CONTINUE THROUGH THE END OF THIS TAF PERIOD. WINDS WILL
INCREASE AGAIN ON FRI MORNING AT ALL TAF SITES WITH GUSTS LIKELY BY
LATE MORNING.
BOUSTEAD
&&
.PREV DISCUSSION... /ISSUED 255 AM CDT THU OCT 31 2013/
DISCUSSION...
SKIES HAD CLEARED ACROSS ALL BUT THE SOUTHEAST PORTION OF THE
FORECAST AREA AT 07Z WITH UPPER TROUGH AXIS STILL OVER THE WESTERN
PLAINS. WV LOOP SHOWING STRONG VORT MAX COMING OUT OF NORTHEAST
NEW MEXICO WHICH MODELS LIFT TOWARD THE LOWER MISSOURI VALLEY
DURING THE DAY. THIS WILL LIKELY MAINTAIN SOME CLOUD COVER OVER
THE SOUTHEAST UNTIL PASSAGE SOMETIME THIS AFTERNOON WITH
INCREASING CLOUDS ELSEWHERE ACROSS THE AREA. HRRR SUGGEST SOME
CHANCE OF SHOWERS FOR FAR SOUTHEAST NEBRASKA AND SOUTHWEST IOWA SO
HAVE PLACED LOW POPS THERE THROUGH THE MORNING. PATCHY FOG MENTION
FOR PARTS OF THE NORTHEAST AND EAST CENTRAL AREAS.
WINDY CONDITIONS MOVE INTO THE AREA ON FRIDAY AS UPPER TROUGH AXIS
SHIFTS EAST OF THE AREA...OTHERWISE GENERALLY DRY WITH SEASONAL
TEMPERATURES EXPECTED INTO SATURDAY.
EXTENDED PERIOD STILL LOOKS TO TURN ACTIVE EARLY NEXT WEEK AFTER
A MILD START ON SUNDAY. PATTERN SIMILAR TO THE RECENT SYSTEM AS
ANOTHER DEEP TROUGH DEVELOPS OVER THE WESTERN CONUS WITH A COLD
FRONT OVER EASTERN PARTS OF KANSAS AND NEBRASKA MONDAY NIGHT INTO
TUESDAY. SETUP PROVIDES ANOTHER CHANCE OF PRECIP FOR THE AREA WITH
A MIX OF RAIN AND SNOW IN PARTS OF THE NORTHEAST WHERE COLDER
TEMPERATURES EXPECTED THIS TIME AROUND.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
158 PM EDT THU OCT 31 2013
.SYNOPSIS...
A WARM FRONT WILL GENERATE SHOWERS TODAY PRIMARILY THROUGH MID
AFTERNOON. A STRONG COLD FRONT WILL BRING ANOTHER ROUND OF SHOWERS
LATE TONIGHT THROUGH LATE FRIDAY MORNING, ALONG WITH STRONG
GUSTY WINDS. FRIDAY AFTERNOON THROUGH SATURDAY MORNING WILL BE
PRIMARILY DRY, BEFORE SCATTERED SHOWERS IMPACT THE AREA SATURDAY
AFTERNOON.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1120 AM UPDATE...SHOWERS NOW CONFINED TO AREAS PRIMARILY EAST/NORTH
OF THE BGM AREA. ACTIVITY CONTINUES MOVING THROUGH AT A GOOD PACE
AND EXPECT THE WIDESPREAD ACTIVITY TO BE NEARLY OVER BY EARLY
AFTERNOON EXCEPT FOR ONEIDA COUNTY. FOR THE REMAINDER OF THE
DAYLIGHT HOURS INTO EARLY EVENING COVERAGE WILL ONLY BE SCATTERED.
830 AM UPDATE...LOCAL RADARS SHOW SHOWERS OVER THE CENTRAL
SOUTHERN TIER AND FINGER LAKES REGION. THIS ACTIVITY IS MOVING
QUICKLY ACROSS CENTRAL NY AND IS ASSOCIATED WITH AN AREA OF STRONG
ISENTROPIC LIFT THAT WILL MOVE THROUGH THE REGION BY EARLY
AFTERNOON. SPED UP POPS THIS MORNING TO REFLECT CURRENT
CONDITIONS. ASSOCIATED LIKELY/CATEGORICAL POPS WITH BAND OF LIFT
ASSOCIATED WITH WARM FRONT THEN DROPPED POPS BACK INTO SCATTERED
COVERAGE ONCE IT PASSES. WIDESPREAD SHOWERS MAY LINGER IN THE
WESTERN CATSKILLS AND NRN CWA INTO THE MID AFTERNOON.
330 AM UPDATE... UL LOW SITTING UP OVR THE DAKOTAS AND EJECTING
SLOWLY TO THE EAST. SIGNIFICANT MOISTURE IS CREEPING UP AHD OF LOW
WITH PW VALUES INCRSG TO 40 MM (1.5 INCHES) OVR THE MID-MS VLY.
THIS IS PROGGED TO WORK UP INTO THE REGION LATE THIS AFTN.
04Z HAND ANALYSIS PLACES WMFNT EXTENDING FM SFC LOW IN IOWA INTO NRN
INDIANA AND OHIO AND SLOWLY HEADING NORTH. DWPTS SOUTH OF THE BNDRY
IN THE MID-ATLANTIC STATES ARE IN THE 50S AND WL WORK UP THIS WAY
THIS AFTN.
AREA OF MODERATE TO HVY RAIN ACRS LWR MICHIGAN DVLPNG IN VICINITY OF
SFC WMFNT ON NOSE OF LLJ. LATEST HRRR RUN BRINGS PCPN INTO WRN ZONES
BY 11Z AND OVRSPRDS MOST OF THE REGION BY AFTN. MAY BE BROKEN ACRS
SRN SXNS THIS AFTN IN THE FORM OF SCTD SHOWERS BASED ON WHAT IS
CURRENTLY GOING ON SOUTH OF SFC WMFNT, THUS WL KEEP JUST SCTD SHOWER
MENTION ALONG AND SOUTH OF THE NRN TIER OF PA.
AFTN MAXES WL TOP OUT IN THE L/M 60S AS 925MB TEMPS CLIMB UP TO ARND
10-12C TDA. THIS IS ALL COURTESY OF WAA THAT WL COMMENCE ACRS THE
REGION AS WMFNT PASSES THRU. CLDY SKIES EXPECTED FOR MOST OF THE DAY
WITH SHOWER ACTIVITY LKLY KEEPING TEMPS FM GETTING OUT OF CONTROL.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
330 AM UPDATE...
PHASING OF S/WVS EXPECTED TONIGHT RESULTING IN DEEPENING SFC LOW
ACRS THE GREAT LKS. H8 LLJ GETS CRANKING BY MIDNIGHT ACRS THE AREA
TO +60KTS THEN ABV 70KTS BY 09Z. BASED ON TRACK OF APPROX 980MB SFC
LOW ACRS SRN ONTARIO BY ALL MODELS, WITH 00Z NAM BEING A TOUCH
FURTHER NORTH, HV DECIDED TO UPGRADE TO HIGH WIND WARNING. BASED ON
LOCAL SYNOPTIC WIND STUDY 6-HR RISE/FALL COUPLET LOOKS TO BE IN THE
BALLPARK FOR HIGH WIND EVENT AND CONFIDENCE IS THERE THAT EXISTING
CNTYS IN WATCH WILL SEE HIGH WINDS AFTER MIDNIGHT TONIGHT. WL ALLOW
DAYSHIFT TO EVALUATE THE NEED FOR WIND ADVISORY ACRS RMNG AREAS TDA.
GIVEN THE STRENGTHENING LLJ AND PHASING OF VORT MAXES TONIGHT EXPECT
OCNL MODERATE SHOWERS LATE WITH QPF AMNTS ACRS THE FAR NORTH IN
VICINITY OF WMFNT APPCHG 1 INCH THRU 12Z FRIDAY. ELSEWHERE EXPECT
ARND 0.50 INCHES.
THO INSTABILITY IS VRY POOR THRU 12Z FRIDAY HV ADDED IN AN ISOLD
THUNDER MENTION AS SHOWALTERS/LI VALUES DIP BLO 0C BTWN 09Z AND 15Z
FRIDAY. CAPES VALUES LOOK TO BE PRETTY PUNY DRG THIS TIME WITH JUST
A COUPLE HUNDRED JOULES, HWVR DYNAMICS ARE EXTREMELY IMPRESSIVE AND
LOW-LVL LR ARE STEEP JUST ALONG AND AHD OF FRONT THUS THINK THAT
THUNDER AT LEAST DESERVES A MENTION, ESPECIALLY CONSIDERING
LIGHTNING STRIKES CURRENTLY OVR LK ERIE.
FROPA LOOKS TO OCCUR SOMETIME FRI MRNG/AFTN WITH HIGH TEMPS ONCE
AGAIN RISING INTO THE 60S ACRS MOST OF THE AREA, THO EXTRM WRN ZONES
MAY TOP OUT ARND 60F. APPEARS THAT THERE WILL BE A SHARP GRADIENT TO
PCPN WITH SHOWERS ENDING IN AREAS WEST OF I-81 AT 18Z AND LINGERING
ACRS ERN ZONES FOR ANOTHER HR OR TWO AFT THIS TIME. CAA WL BE
DELAYED UNTIL THE VRY END OF THE SHORT TERM WITH OVRNGT MINS AND
AFTN MAXES STILL ABV NORMAL FOR SATURDAY.
ANOTHER TROF/ASSOC SFC LOW WL MV INTO AREA FM THE NW BY 12Z
SATURDAY. WINDS WL BCM SRLY AHD OF THIS SFC SYSTEM AND QUICKLY SHIFT
ARND TO THE NW AS LOPRES PASSES ON SATURDAY. THIS WL SET THE STAGE
FOR LK EFFECT SHOWERS ON SAT AFTN AND EVENTUALLY A MIX WITH AND
CHANGE OVR TO SNOW ON SUN MRNG. HV MADE NO CHGS TO THESE GRIDS AT
THIS TIME DUE TO NEAR TERM CHALLENGES.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
LONG TERM STARTS OUT DRY AND VERY COLD AS A 1034MB SFC HIPRES
BLDS INTO SW QUEBEC AND BRINGS A NE FLOW INTO THE FCST AREA.
COLDEST NGT SO FAR SEEMS LIKELY WITH LOW IN THE UPR TEENS PSBL MON
MRNG. SFC HI SLOWLY SLIDES EAST OVER THE NEXT 48 HRS AS THE UPR
RDG BLDS OVER THE AREA. RETURN FLOW BEGINS THE WAA PROCESS LTR MON
AND CONTG INTO WED. NEXT LOW DVLPG OVER THE LAKES IS HELD OFF BY
THE BLDG RDG AND DRY AIR IN PLACE. SO THE NEXT CHANCE FOR PCPN
WILL BE ON THU AS THE COLD FNT SWEEPS THRU THE AREA. AS IS
TYPICAL...GFS IS A GOOD 12 HRS AHD OF THE EURO IN THE TIMING OF
THE FNTL PASSAGE SO WILL JUST STICK WITH CHANCE POPS FOR NOW UNTIL
THE TIMING IS FIGURED OUT. I WOULD GUESS THAT THE GFS IS A BIT
CLOSER TO THE CORRECT TIME...BUT IN GNRL THE TRUTH LIES BETWEEN.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
SLY FLOW OF DEEP MOISTURE WILL BE OVER THE REGION AHD OF A COLD
FNT. FEW SPOTS BROKE OUT THIS AFTN TO VFR BUT THE TREND LTR AND
OVRNGT WILL BE TO IFR IN NEAR STEADY RAIN AND LGT FOG AS THE
LOWERS LVLS STABILIZE. STRONGER WINDS ARE LIKELY ON THE HILLTOP
STATIONS AS THE GRADIENT TIGHTENS AND THE LOW DEEPENS AND ADVANCES
EWRD. IT WILL BE TOUGHER TO BRING THE HIGHER WINDS DOWN INTO THE
VLY AND LWR ELEVATION AIRPORTS WITH THE STABLE LYR. DRAMATIC COLD
FNT PASSAGE ARND 15Z WILL BRING A RAPID RETURN TO VFR BUT WITH
VERY GUSTY WLY WINDS AS WE MIX MUCH STRONGER WINDS ALOFT TO THE
SFC.
OUTLOOK...
FRI NGT...VFR W/GUSTY WINDS
SAT/SAT NGT...MVFR IN SHRA/SHSN PRIMARILY CNTRL NY.
SUN...MVFR EARLY CNTRL NY IN -SHRA/-SHSN...IMPRVG TO VFR.
MON/TUE...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...HIGH WIND WARNING FROM 2 AM TO 2 PM EDT FRIDAY FOR NYZ009-
015>018-036-037.
&&
$$
SYNOPSIS...PVN
NEAR TERM...PVN/RRM
SHORT TERM...PVN
LONG TERM...DGM
AVIATION...DGM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
257 PM EDT THU OCT 31 2013
.SYNOPSIS...
MOISTURE WILL INCREASE TONIGHT AHEAD OF A COLD FRONT EXPECTED TO
CROSS THE AREA FRIDAY AND FRIDAY NIGHT BEFORE COOLER CONDITIONS
RETURN FOR THE WEEKEND.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 230 PM THURSDAY...
TEMPERATURES THIS AFTERNOON ARE FOR THE MOST PART ON TRACK TO CLIMB
INTO THE MID TO UPPER 70S IN THE SOUTHEAST AND MAYBE A COUPLE
DEGREES COOLER THAN EXPECTED IN THE EXTREME TRIAD AS THEY STRUGGLE
TO GET TO 70 DEGREES WITH A BIT MORE CLOUD COVER AND SOME
DRIZZLE/SPRINKLES MOVING THROUGH THE AREA OVER THE NEXT COUPLE OF
HOURS. RADAR SHOWS VERY LIGHT RAIN MOVING SOUTHWEST. NEW DEVELOPMENT
ON THE SOUTHERN EDGE OF THIS FEATURE OVER UPSTATE SOUTH CAROLINA
WILL MOVE NORTHEASTWARD INTO OUR SOUTHWEST PIEDMONT LATER IN THE
AFTERNOON. ADVECTION OF THIS FEATURE FURTHER TO THE EAST WILL BE
HARDER AS THE LATEST RUN OF THE RAP SHOWS A SWATH OF DRIER
1000-500MB AIR ASSOCIATED WITH AN UPPER LEVEL HIGH PRESSURE SYSTEM
TO THE SOUTH MOVING UP THROUGH THE TRIANGLE AND POINTS EASTWARD.
THIS SHOULD HELP TO KEEP THINGS DRY OR AT THE VERY LEAST KEEP
SHOWERS TO A MINIMUM. CURRENT WINDS OUT OF THE SOUTH SOUTHWEST AT 10
KNOTS GUSTING TO 20 KNOTS ARE EXPECTED TO CONTINUE THIS AFTERNOON
AND INTO THE EVENING AND POSSIBLY STRENGTHEN A FEW KNOTS IN THE
PROCESS. EXPECT AT LEAST UPPER LEVEL CLOUD COVER TO INCREASE AS THE
DAY GOES ON FROM WEST TO EAST AS THE FRONTAL SYSTEM CROSSING THE
MISSISSIPPI PUSHES FURTHER EAST.
FOR TONIGHT...WINDS ARE EXPECTED TO REMAIN BREEZY OUT OF THE
SOUTHWEST OVERNIGHT BUT THIS ACTIVITY MAY BE MORE SPORADIC DURING
THE EARLY MORNING HOURS. MODEL FORECAST SOUNDINGS SHOWN IN BUFKIT
HAVE A SATURATED LAYER BETWEEN 900 AND 750 MB TONIGHT WHICH IS WHERE
MOISTURE FOR ANY LIGHT SHOWER ACTIVITY WOULD COME FROM...ABOVE THAT
A STRONG TEMPERATURE INVERSION AT 700 MB SHOULD KEEP THINGS CAPPED
OVERNIGHT. WITH LIMITED TO NO INSTABILITY...SHOWER ACTIVITY MAY BE
HARD TO COME BY. LOWS ARE ONLY EXPECTED TO DROP INTO THE MID 60S IN
MOST LOCATIONS.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 300 PM THURSDAY...
A FRONTAL SYSTEM ASSOCIATED WITH A STRONG LOW PRESSURE SYSTEM MOVING
NORTHEASTWARD THROUGH THE GREAT LAKES. WILL BE ON THE DOORSTEP BY
FRIDAY MORNING WITH PRECIPITATION EXPECTED TO BEGIN IN THE TRIAD
BETWEEN 9 AND 12Z...15Z AT RDU AND 18Z AT KFAY AND KRWI. INSTABILITY
WILL BE VERY LIMITED WITH THIS SYSTEM ALTHOUGH SHEAR VALUES WILL BE
VERY STRONG THROUGHOUT THE EVENT. GUSTY WINDS OF UP TO 25 KNOTS CAN
BE EXPECTED ON FRIDAY. IT IS NOT OUT OF THE QUESTION THAT A STRONGER
SHOWER COULD HELP TO BRING STRONGER 40-50 KNOT 850 MB WINDS DOWN TO
THE SURFACE. AS THE FRONT MOVES EASTWARD SURFACE WINDS OUT AHEAD OF
THE FRONT WILL BACK AROUND FROM SOUTHWESTERLY TO
SOUTHERLY...ESPECIALLY ACROSS EASTERN NORTH CAROLINA. THIS IS
CLEARLY INDICATED ON MODEL HODOGRAPHS WHICH SHOW SWEEPING CLOCKWISE
HODOGRAPHS FOR MUCH OF THE DAY FRIDAY INDICATING THAT THERE COULD BE
SOME ROTATION PRESENT...ESPECIALLY FOR I-95 AND POINTS EAST. THE
DEVELOPMENT OF A SURFACE LOW ALONG THE FRONT LATER IN THE EVENING
GIVES FURTHER CREDIBILITY TO THIS THEORY BUT CURRENT SIMULATIONS
SHOW THE FRONT PROGRESSING THROUGH OUR CWA BEFORE THIS HAPPENS. AT
THE CURRENT TIME SPC HAS MAINTAINED A SEE TEXT FOR OUR AREA FOR
FRIDAY SIGHTING AN OUTSIDE CHANCE OF DAMAGING WINDS AND A NON-ZERO
TORNADO THREAT BUT ADDING THE CAVEAT THAT VERY LIMITED INSTABILITY
AND LAPSE RATES MAKE THE SEVERE WEATHER THREAT FAIRLY MUNDANE AND
NOT WORTHY OF A SLIGHT RISK AT THIS POINT.
AS FAR AS QPF VALUES ARE CONCERNED THE LATEST RUN OF THE NAM
AVERAGES OUT AROUND A QUARTER OF AN INCH WITH STRONGER PULSES
POTENTIALLY PUSHING THE TOTALS AT SOME LOCATIONS UP TOWARDS A HALF
OF AN INCH. WITH SOUTHWESTERLY FLOW IN PLACE ALL DAY ON
SATURDAY...MAXIMUM TEMPERATURES SHOULD RISE INTO THE UPPER 70S IN
THE EAST WHERE GREATER INSOLATION WILL OCCUR. BACK TO THE
NORTHWEST...CLOUD COVER ASSOCIATED WITH THE FRONT WILL KEEP HIGHS
DOWN CLOSER TO 70. ON FRIDAY NIGHT FRONTAL PASSAGE WITH WIND
SHIFTING TO NORTHWESTERLY IS NOT EXPECTED TO OCCUR UNTIL AFTER 6Z IN
THE TRIAD...CLOSER TO 9Z AT KRDU AND NEAR 12Z IN THE EAST. THIS
TIMING WILL ALSO HELP TO CLEAR THINGS OUT IN THE WEST BEFORE SUNRISE
AND THEREFORE LEAVING ANOTHER STRONG TEMPERATURE GRADIENT IN THE
OVERNIGHT LOWS. WHILE THE TRIAD WILL BE NEAR 50 DEGREES...MIDDLE 60S
ARE STILL LIKELY IN THE SOUTHEAST WHERE SOUTHERLY WINDS AND CLOUDS
WILL HANG ON THE LONGEST.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 205 PM THURSDAY...
FOR SATURDAY/SATURDAY NIGHT: LATEST MODEL GUIDANCE INDICATES THAT
THE COLD FRONT WILL BE EAST OF THE CWA... ALONG COASTAL SECTIONS OF
NC BY DAWN SATURDAY. RAIN CHANCES SHOULD EXTEND INTO MID MORNING IN
AREAS ALONG/EAST OF I-95 BEFORE QUICKLY ENDING BY LATE MORNING...
THEN EXPECT A PERIOD OF MOSTLY SUNNY SKIES LATE MORNING THROUGH
EARLY AFTERNOON WITH WNW DOWNSLOPE FLOW AND A DRYING COLUMN. A
SECONDARY SURFACE FRONT... ASSOCIATED WITH THE MID LEVEL TROUGH
AXIS... WILL CROSS CENTRAL NC NW TO SE FROM MID AFTERNOON THROUGH
EARLY EVENING. MID LEVEL DPVA... A SHOT OF UPPER DIVERGENCE... AND
LOW LEVEL LAPSE RATES OF 6.5-7.0 C/KM ARE ANTICIPATED ALONG AND
AHEAD OF THIS FRONT. FORECAST SOUNDINGS DEPICT ENOUGH SATURATION
ACCOMPANYING THESE STEEP LAPSE RATES IN THE 850-600 MB LAYER DURING
THIS TIME TO SUPPORT ADDING A SLIGHT CHANCE OF SHOWERS AREAWIDE. THE
MOIST LAYER EXTENDS UP INTO THE -12C TO -16C RANGE... SO GIVEN THE
EXPECTED INSTABILITY AND AUGMENTED LIFT BY MID-UPPER LEVEL
FORCING... WE COULD SEE A STORM OR TWO AS WELL... BUT WILL HOLD OFF
ADDING THUNDER AT THIS TIME GIVEN THE EXPECTED SPARSITY OF COVERAGE.
THE FAIRLY DEEP AND DRYING SUBCLOUD LAYER SHOULD LIMIT QPF DESPITE
DECENT COVERAGE... AND MANY PLACES MAY SEE JUST A TRACE... BUT THIS
LOW LEVEL DRY AIR COULD ALSO MEAN ENHANCED DOWNDRAFTS AND ISOLATED
OCCURRENCES OF STRONG WIND GUSTS WITH THESE SHOWERS. THERMAL
STRUCTURE ON FORECAST SOUNDINGS SUPPORT HIGHS OF 66-73. LOWS 40-45
WITH CLEARING SKIES... AND COLD AIR ADVECTION BEING OFFSET SOMEWHAT
BY CONTINUED MIXING OVERNIGHT.
FOR SUNDAY THROUGH THURSDAY: QUIET AND MOSTLY DRY WEATHER WITH A
WARMING TREND... AS COOL SURFACE HIGH PRESSURE DRIFTS EASTWARD OVER
EASTERN NOAM BEFORE MODIFYING AND MOVING OFF THE COAST. THE
FULL-LATITUDE MID LEVEL TROUGH THAT AFFECTS NC SATURDAY WILL SHIFT
OFF THE EASTERN SEABOARD EARLY SUNDAY... THEN AN AMPLIFYING LONGWAVE
TROUGH DIGGING OVER THE ROCKIES AND HIGH PLAINS WILL INDUCE
STRENGTHENING RIDGING ALOFT OVER THE SOUTHEAST AND CAROLINAS THROUGH
MID WEEK. BELOW TO MUCH BELOW NORMAL TEMPS ARE EXPECTED
SUNDAY/MONDAY WITH FAIR TO MOSTLY CLEAR SKIES. BY TUESDAY... THE
SURFACE HIGH WILL PASS OFF THE CANADIAN MARITIME COAST WHILE NOSING
SSW INTO NC IN A WEDGE-LIKE FASHION... CAPPED BY A CLOSED MID LEVEL
ANTICYCLONE JUST OFF THE CAROLINAS (ECMWF HAS A STRONGER RIDGE
CLOSER TO OUR COAST WHILE THE GFS IS WEAKER AND A BIT MORE SE). THIS
FAVORS A PATTERN OF MOIST/STABLE LOW LEVELS (WITH INCREASED MOIST
ATLANTIC INFLOW AROUND THE SURFACE RIDGE AND UPSLOPE FLOW ALONG WITH
ISENTROPIC UPGLIDE) CAPPED WITH DRY/STABLE AIR ABOVE 800 MB. WE
SHOULD SEE INCREASING CLOUD COVER TUESDAY INTO THURSDAY... WITH A
SLIGHT CHANCE OF SOME DRIZZLE... PARTICULARLY EARLY TUESDAY MORNING
WITH A BETTER CHANCE TUESDAY NIGHT/WEDNESDAY MORNING... ESPECIALLY
OVER THE WRN PIEDMONT HEADING INTO THE HIGHER TERRAIN. EXPECT NEAR
NORMAL TEMPS TUESDAY... WARMING TO ABOUT A CATEGORY ABOVE NORMAL BY
THURSDAY AS THE WEDGE AIR MASS WEAKENS AND SLOWLY WARMS. THE WESTERN
TROUGH WILL START TO LIFT THROUGH THE CENTRAL US LATE THURSDAY WITH
ITS SURFACE COLD FRONT APPROACHING... BUT ACCORDING TO THE FAVORED
SLOWER ECMWF SOLUTION... THE ATTENDING BAND OF CONVECTION SHOULD
HOLD WEST OF THE FORECAST AREA THROUGH THURSDAY. WILL INCLUDE JUST A
SMALL CHANCE OF PREFRONTAL SHOWERS LATE WEDNESDAY THROUGH THURSDAY
MAINLY IN THE WRN PIEDMONT. -GIH
&&
.AVIATION /18Z THURSDAY THROUGH WEDNESDAY/...
AS OF 200 PM THURSDAY...
24 HOUR TAF PERIOD: RATHER COMPLICATED TAF PERIOD ACROSS THE CWA AS
A FRONTAL SYSTEM APPROACHES THE AREA EARLY FRIDAY MORNING. FOR THE
REST OF TODAY EXPECT BREEZY SOUTHERLY TO SOUTHWESTERLY FLOW AT ALL
SITES WITH GUSTS OF 15 TO 20 MPH LIKELY AND INCREASING A BIT INTO
THE EVENING HOURS. FOR THE MOST PART...TERMINALS SHOULD REMAIN DRY
BUT SOME PATCHY DRIZZLE/SPRINKLES IS MOVING INTO WESTERN AREAS AT
THIS TIME. THIS IS IN RESPONSE TO SOME MOISTURE ADVECTION FROM THE
SOUTH AND IS NOT EXPECTED TO DEVELOP BUT THIS TYPE OF ACTIVITY COULD
CONTINUE THROUGH THE EVENING. THE TREND FOR THIS WILL BE LESS
FURTHER TO THE EAST. OVERNIGHT...SOME LOW CEILINGS ARE EXPECTED TO
BEGIN SHOWING UP AFTER 6Z OR SO IN THE WEST WITH IFR CEILINGS LIKELY
THE PREDOMINANT CATEGORY BUT IT WILL NOT BE UNCOMMON FOR CEILINGS TO
JUMP BETWEEN LIFR/MVFR. GUSTS ARE EXPECTED TO CONTINUE THROUGH THE
OVERNIGHT HOURS BUT MAY WAX AND WANE IN INTENSITY.
FOR FRIDAY EXPECT THE FIRST PRECIPITATION WITH THE FRONT TO ENTER
THE TRIAD AROUND 12Z. RAIN OF LIGHT TO MODERATE INTENSITY IS
EXPECTED WITH SOME POCKETS OF HEAVIER SHOWERS. WINDS WILL REMAIN OUT
OF THE SOUTHWEST AT 15 KNOTS GUSTING TO NEAR 25 KNOTS. PRECIPITATION
WILL MARCH WESTWARD APPROACHING KRDU BY 15Z AND KFAY BY 18Z. KRWI
SHOULD STAY DRY FOR THE REMAINDER OF THE TAF PERIOD. CEILINGS AND
VISIBILITIES SHOULD GO DOWN TO MVFR LEVELS WITH THE ARRIVAL OF PRE
FRONTAL PRECIPITATION AND WILL STAY DOWN AT KINT...KGSO...AND KRDU.
KFAY AND KRWI MAY SEE IMPROVEMENT IN AVIATION CONDITIONS TO VFR
AFTER SUNRISE THROUGH THE END OF THE PERIOD.
LONG TERM:
FOR SATURDAY A SECONDARY WAVE ASSOCIATED WITH THE UPPER LEVEL
TROUGH WILL PASS OVER THE AREA AND MAY PRESENT SOME PROBLEMS FOR
AVIATION CONDITIONS. BEYOND THAT HIGH PRESSURE MOVES NORTH OF THE
AREA WITH GENERALLY EASTERLY FLOW AND A POTENTIAL COLD AIR DAMMING
SITUATION THROUGH EARLY NEXT WEEK WHICH COULD ALSO PLAY HAVOC ON
CEILINGS.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...ELLIS
NEAR TERM...ELLIS
SHORT TERM...ELLIS
LONG TERM...HARTFIELD
AVIATION...ELLIS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
231 PM EDT THU OCT 31 2013
.SYNOPSIS...
MOISTURE WILL INCREASE TONIGHT AHEAD OF A COLD FRONT EXPECTED TO
CROSS THE AREA FRIDAY AND FRIDAY NIGHT BEFORE COOLER CONDITIONS
RETURN FOR THE WEEKEND.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 230 PM THURSDAY...
TEMPERATURES THIS AFTERNOON ARE FOR THE MOST PART ON TRACK TO CLIMB
INTO THE MID TO UPPER 70S IN THE SOUTHEAST AND MAYBE A COUPLE
DEGREES COOLER THAN EXPECTED IN THE EXTREME TRIAD AS THEY STRUGGLE
TO GET TO 70 DEGREES WITH A BIT MORE CLOUD COVER AND SOME
DRIZZLE/SPRINKLES MOVING THROUGH THE AREA OVER THE NEXT COUPLE OF
HOURS. RADAR SHOWS VERY LIGHT RAIN MOVING SOUTHWEST. NEW DEVELOPMENT
ON THE SOUTHERN EDGE OF THIS FEATURE OVER UPSTATE SOUTH CAROLINA
WILL MOVE NORTHEASTWARD INTO OUR SOUTHWEST PIEDMONT LATER IN THE
AFTERNOON. ADVECTION OF THIS FEATURE FURTHER TO THE EAST WILL BE
HARDER AS THE LATEST RUN OF THE RAP SHOWS A SWATH OF DRIER
1000-500MB AIR ASSOCIATED WITH AN UPPER LEVEL HIGH PRESSURE SYSTEM
TO THE SOUTH MOVING UP THROUGH THE TRIANGLE AND POINTS EASTWARD.
THIS SHOULD HELP TO KEEP THINGS DRY OR AT THE VERY LEAST KEEP
SHOWERS TO A MINIMUM. CURRENT WINDS OUT OF THE SOUTH SOUTHWEST AT 10
KNOTS GUSTING TO 20 KNOTS ARE EXPECTED TO CONTINUE THIS AFTERNOON
AND INTO THE EVENING AND POSSIBLY STRENGTHEN A FEW KNOTS IN THE
PROCESS. EXPECT AT LEAST UPPER LEVEL CLOUD COVER TO INCREASE AS THE
DAY GOES ON FROM WEST TO EAST AS THE FRONTAL SYSTEM CROSSING THE
MISSISSIPPI PUSHES FURTHER EAST.
FOR TONIGHT...WINDS ARE EXPECTED TO REMAIN BREEZY OUT OF THE
SOUTHWEST OVERNIGHT BUT THIS ACTIVITY MAY BE MORE SPORADIC DURING
THE EARLY MORNING HOURS. MODEL FORECAST SOUNDINGS SHOWN IN BUFKIT
HAVE A SATURATED LAYER BETWEEN 900 AND 750 MB TONIGHT WHICH IS WHERE
MOISTURE FOR ANY LIGHT SHOWER ACTIVITY WOULD COME FROM...ABOVE THAT
A STRONG TEMPERATURE INVERSION AT 700 MB SHOULD KEEP THINGS CAPPED
OVERNIGHT. WITH LIMITED TO NO INSTABILITY...SHOWER ACTIVITY MAY BE
HARD TO COME BY. LOWS ARE ONLY EXPECTED TO DROP INTO THE MID 60S IN
MOST LOCATIONS.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 330 AM THURSDAY...
ALTHOUGH THE BEST DPVA/HEIGHT FALLS WILL PASS WELL N/NW OF CENTRAL
NC ON FRI AS THE POTENT SHORTWAVE TRACKS NE FROM THE GREAT LAKES
INTO EASTERN CANADA...A PROLONGED PERIOD OF RELATIVELY STRONG
SFC-925 MB CONVERGENCE IS EXPECTED WITH THE SFC-925 MB TROUGH AS IT
PROGRESSES SLOWLY EAST ACROSS THE CAROLINAS ON FRIDAY...AND THE
SOUTHERLY LLJ ON THE EASTERN PERIPHERY OF THE TROUGH WILL HAVE AMPLE
TIME TO ADVECT PLENTIFUL LOW-LEVEL MOISTURE INTO THE REGION...WITH
PWAT VALUES WELL ABOVE NORMAL AROUND ~1.75" AND SFC DEWPOINTS
APPROACHING 65-67F...EXCELLENT FOR THIS TIME OF YEAR. SOME UPPER
FORCING MAY BE PRESENT FRI/FRI EVENING IN THE FORM OF SMALL
AMPLITUDE DISTURBANCES IN SW FLOW ALOFT OR IN ASSOC/W THE RIGHT
ENTRANCE REGION OF A STRONG UPPER LEVEL JET OVER THE MID-ATLANTIC.
LATE FRI NIGHT...ADDITIONAL SHORTWAVE ENERGY TRACKING SOUTHEAST
THROUGH THE UPPER MIDWEST/CENTRAL MS RIVER VALLEY WILL AMPLIFY
CYCLONIC FLOW ALOFT ACROSS THE TN/OH VALLEY AND PERHAPS STRENGTHEN
FORCING FOR ASCENT FURTHER DOWNSTREAM OVER THE CAROLINAS. GIVEN THE
AFOREMENTIONED FACTORS AND THAT THE LATEST MODEL GUIDANCE REMAINS
CONSISTENT WITH PREVIOUS RUNS (ALL SHOWING MEASURABLE PRECIP OVER
CENTRAL NC)...WILL MAKE LITTLE CHANGE TO PRIOR FORECASTS WITH REGARD
TO PRECIP CHANCES/TIMING/AMOUNTS...WITH PRECIP CHANCES EVENTUALLY
DECREASING FROM WEST-EAST FRI NIGHT.
HIGHS ON FRI WILL BE DICTATED BY PERVASIVE CLOUD COVER AND
PRECIPITATION...ESPECIALLY IN THE WESTERN PIEDMONT. BETTER
INSOLATION AND/OR THINNER CLOUD COVER WILL BE POSSIBLE IN THE EAST
WHERE THE DRIER MID-LEVEL AIRMASS WILL LINGER LONGER BEFORE ERODING.
WITH THE ABOVE IN MIND...EXPECT HIGHS RANGING FROM THE UPPER 60S TO
NEAR 70F IN THE NW PIEDMONT TO THE UPPER 70S /NEAR 80F/ IN THE
COASTAL PLAIN.
DIURNAL DESTABILIZATION WILL BE SIGNIFICANTLY HAMPERED BY CLOUD
COVER ON FRI. RELATIVELY STEEP MID-LEVEL LAPSE RATES ARE EXPECTED TO
WEAKEN FROM WEST-EAST DURING THE DAY...AND MLCAPE MAY STRUGGLE TO
REACH 100-250 J/KG IN THE WEST...THOUGH PERHAPS REACHING 250-500
J/KG IN THE EAST. GIVEN THAT THE BEST DPVA/HEIGHT FALLS WILL PASS
WELL TO THE NORTH WITH FORCING PRIMARILY LIMITED TO THE LOWER-LEVELS
AND MARGINAL INSTABILITY AT BEST IT IS DIFFICULT TO ASCERTAIN THE
POTENTIAL FOR THUNDERSTORMS LET ALONE SEVERE WEATHER. AT THIS TIME
WILL CONTINUE TO MENTION A LOW-END POTENTIAL FOR DAMAGING WINDS
GIVEN STRONG LOW/MID LEVEL FLOW AND ATTENDANT INCREASED POTENTIAL
FOR MOMENTUM TRANSPORT...ESPECIALLY IF THE DRY MID-LEVEL AIRMASS CAN
LINGER LONG ENOUGH IN EASTERN PORTIONS OF THE AREA. ADDITIONALLY...
GIVEN THE POTENTIAL FOR A WEAK WAVE OF LOW PRESSURE DEVELOPING ALONG
THE FRONT AND TRACKING NE FROM ROUGHLY CLT-RDU-ORF FRI AFT/EVE INTO
FRI NIGHT...A LOW-END POTENTIAL FOR AN ISOLD TORNADO CANNOT BE RULED
OUT. -VINCENT
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 205 PM THURSDAY...
FOR SATURDAY/SATURDAY NIGHT: LATEST MODEL GUIDANCE INDICATES THAT
THE COLD FRONT WILL BE EAST OF THE CWA... ALONG COASTAL SECTIONS OF
NC BY DAWN SATURDAY. RAIN CHANCES SHOULD EXTEND INTO MID MORNING IN
AREAS ALONG/EAST OF I-95 BEFORE QUICKLY ENDING BY LATE MORNING...
THEN EXPECT A PERIOD OF MOSTLY SUNNY SKIES LATE MORNING THROUGH
EARLY AFTERNOON WITH WNW DOWNSLOPE FLOW AND A DRYING COLUMN. A
SECONDARY SURFACE FRONT... ASSOCIATED WITH THE MID LEVEL TROUGH
AXIS... WILL CROSS CENTRAL NC NW TO SE FROM MID AFTERNOON THROUGH
EARLY EVENING. MID LEVEL DPVA... A SHOT OF UPPER DIVERGENCE... AND
LOW LEVEL LAPSE RATES OF 6.5-7.0 C/KM ARE ANTICIPATED ALONG AND
AHEAD OF THIS FRONT. FORECAST SOUNDINGS DEPICT ENOUGH SATURATION
ACCOMPANYING THESE STEEP LAPSE RATES IN THE 850-600 MB LAYER DURING
THIS TIME TO SUPPORT ADDING A SLIGHT CHANCE OF SHOWERS AREAWIDE. THE
MOIST LAYER EXTENDS UP INTO THE -12C TO -16C RANGE... SO GIVEN THE
EXPECTED INSTABILITY AND AUGMENTED LIFT BY MID-UPPER LEVEL
FORCING... WE COULD SEE A STORM OR TWO AS WELL... BUT WILL HOLD OFF
ADDING THUNDER AT THIS TIME GIVEN THE EXPECTED SPARSITY OF COVERAGE.
THE FAIRLY DEEP AND DRYING SUBCLOUD LAYER SHOULD LIMIT QPF DESPITE
DECENT COVERAGE... AND MANY PLACES MAY SEE JUST A TRACE... BUT THIS
LOW LEVEL DRY AIR COULD ALSO MEAN ENHANCED DOWNDRAFTS AND ISOLATED
OCCURRENCES OF STRONG WIND GUSTS WITH THESE SHOWERS. THERMAL
STRUCTURE ON FORECAST SOUNDINGS SUPPORT HIGHS OF 66-73. LOWS 40-45
WITH CLEARING SKIES... AND COLD AIR ADVECTION BEING OFFSET SOMEWHAT
BY CONTINUED MIXING OVERNIGHT.
FOR SUNDAY THROUGH THURSDAY: QUIET AND MOSTLY DRY WEATHER WITH A
WARMING TREND... AS COOL SURFACE HIGH PRESSURE DRIFTS EASTWARD OVER
EASTERN NOAM BEFORE MODIFYING AND MOVING OFF THE COAST. THE
FULL-LATITUDE MID LEVEL TROUGH THAT AFFECTS NC SATURDAY WILL SHIFT
OFF THE EASTERN SEABOARD EARLY SUNDAY... THEN AN AMPLIFYING LONGWAVE
TROUGH DIGGING OVER THE ROCKIES AND HIGH PLAINS WILL INDUCE
STRENGTHENING RIDGING ALOFT OVER THE SOUTHEAST AND CAROLINAS THROUGH
MID WEEK. BELOW TO MUCH BELOW NORMAL TEMPS ARE EXPECTED
SUNDAY/MONDAY WITH FAIR TO MOSTLY CLEAR SKIES. BY TUESDAY... THE
SURFACE HIGH WILL PASS OFF THE CANADIAN MARITIME COAST WHILE NOSING
SSW INTO NC IN A WEDGE-LIKE FASHION... CAPPED BY A CLOSED MID LEVEL
ANTICYCLONE JUST OFF THE CAROLINAS (ECMWF HAS A STRONGER RIDGE
CLOSER TO OUR COAST WHILE THE GFS IS WEAKER AND A BIT MORE SE). THIS
FAVORS A PATTERN OF MOIST/STABLE LOW LEVELS (WITH INCREASED MOIST
ATLANTIC INFLOW AROUND THE SURFACE RIDGE AND UPSLOPE FLOW ALONG WITH
ISENTROPIC UPGLIDE) CAPPED WITH DRY/STABLE AIR ABOVE 800 MB. WE
SHOULD SEE INCREASING CLOUD COVER TUESDAY INTO THURSDAY... WITH A
SLIGHT CHANCE OF SOME DRIZZLE... PARTICULARLY EARLY TUESDAY MORNING
WITH A BETTER CHANCE TUESDAY NIGHT/WEDNESDAY MORNING... ESPECIALLY
OVER THE WRN PIEDMONT HEADING INTO THE HIGHER TERRAIN. EXPECT NEAR
NORMAL TEMPS TUESDAY... WARMING TO ABOUT A CATEGORY ABOVE NORMAL BY
THURSDAY AS THE WEDGE AIR MASS WEAKENS AND SLOWLY WARMS. THE WESTERN
TROUGH WILL START TO LIFT THROUGH THE CENTRAL US LATE THURSDAY WITH
ITS SURFACE COLD FRONT APPROACHING... BUT ACCORDING TO THE FAVORED
SLOWER ECMWF SOLUTION... THE ATTENDING BAND OF CONVECTION SHOULD
HOLD WEST OF THE FORECAST AREA THROUGH THURSDAY. WILL INCLUDE JUST A
SMALL CHANCE OF PREFRONTAL SHOWERS LATE WEDNESDAY THROUGH THURSDAY
MAINLY IN THE WRN PIEDMONT. -GIH
&&
.AVIATION /18Z THURSDAY THROUGH WEDNESDAY/...
AS OF 200 PM THURSDAY...
24 HOUR TAF PERIOD: RATHER COMPLICATED TAF PERIOD ACROSS THE CWA AS
A FRONTAL SYSTEM APPROACHES THE AREA EARLY FRIDAY MORNING. FOR THE
REST OF TODAY EXPECT BREEZY SOUTHERLY TO SOUTHWESTERLY FLOW AT ALL
SITES WITH GUSTS OF 15 TO 20 MPH LIKELY AND INCREASING A BIT INTO
THE EVENING HOURS. FOR THE MOST PART...TERMINALS SHOULD REMAIN DRY
BUT SOME PATCHY DRIZZLE/SPRINKLES IS MOVING INTO WESTERN AREAS AT
THIS TIME. THIS IS IN RESPONSE TO SOME MOISTURE ADVECTION FROM THE
SOUTH AND IS NOT EXPECTED TO DEVELOP BUT THIS TYPE OF ACTIVITY COULD
CONTINUE THROUGH THE EVENING. THE TREND FOR THIS WILL BE LESS
FURTHER TO THE EAST. OVERNIGHT...SOME LOW CEILINGS ARE EXPECTED TO
BEGIN SHOWING UP AFTER 6Z OR SO IN THE WEST WITH IFR CEILINGS LIKELY
THE PREDOMINANT CATEGORY BUT IT WILL NOT BE UNCOMMON FOR CEILINGS TO
JUMP BETWEEN LIFR/MVFR. GUSTS ARE EXPECTED TO CONTINUE THROUGH THE
OVERNIGHT HOURS BUT MAY WAX AND WANE IN INTENSITY.
FOR FRIDAY EXPECT THE FIRST PRECIPITATION WITH THE FRONT TO ENTER
THE TRIAD AROUND 12Z. RAIN OF LIGHT TO MODERATE INTENSITY IS
EXPECTED WITH SOME POCKETS OF HEAVIER SHOWERS. WINDS WILL REMAIN OUT
OF THE SOUTHWEST AT 15 KNOTS GUSTING TO NEAR 25 KNOTS. PRECIPITATION
WILL MARCH WESTWARD APPROACHING KRDU BY 15Z AND KFAY BY 18Z. KRWI
SHOULD STAY DRY FOR THE REMAINDER OF THE TAF PERIOD. CEILINGS AND
VISIBILITIES SHOULD GO DOWN TO MVFR LEVELS WITH THE ARRIVAL OF PRE
FRONTAL PRECIPITATION AND WILL STAY DOWN AT KINT...KGSO...AND KRDU.
KFAY AND KRWI MAY SEE IMPROVEMENT IN AVIATION CONDITIONS TO VFR
AFTER SUNRISE THROUGH THE END OF THE PERIOD.
LONG TERM:
FOR SATURDAY A SECONDARY WAVE ASSOCIATED WITH THE UPPER LEVEL
TROUGH WILL PASS OVER THE AREA AND MAY PRESENT SOME PROBLEMS FOR
AVIATION CONDITIONS. BEYOND THAT HIGH PRESSURE MOVES NORTH OF THE
AREA WITH GENERALLY EASTERLY FLOW AND A POTENTIAL COLD AIR DAMMING
SITUATION THROUGH EARLY NEXT WEEK WHICH COULD ALSO PLAY HAVOC ON
CEILINGS.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...ELLIS
NEAR TERM...ELLIS
SHORT TERM...VINCENT
LONG TERM...HARTFIELD
AVIATION...ELLIS
AREA FORECAST DISCUSSION
NWS PORTLAND OR
922 AM PDT THU OCT 31 2013
.SYNOPSIS...A WEAK WARM FRONT BROUGHT LIGHT RAIN AND DRIZZLE TO THE
REGION THIS MORNING. A WEAKENING SURFACE TROUGH WILL MOVE ACROSS
TODAY BRINGING A FEW SHOWERS LATER TODAY. HIGH PRESSURE WILL BRING
DRIER WEATHER TO THE REGION FRIDAY. A STRONGER STORM SYSTEM SATURDAY
WILL BRING BREEZY CONDITIONS ALONG THE COAST...VALLEY RAIN AND
MOUNTAIN SNOW. RELATIVELY MORE QUIET WEATHER SHOULD RETURN LATE IN
THE WEEKEND INTO EARLY NEXT BEFORE ANOTHER SERIES OF EVEN COLDER
STORM SYSTEMS POSSIBLY IMPACT THE REGION DURING THE MIDDLE TO LATTER
PART OF NEXT WEEK.
&&
.SHORT TERM...AN AAREA OF WARM AIR ADVECTION WAS BRINGING AREAS OF
LIGHT RAIN TO THE REGION THIS MORNING. RADAR AND SURFACE
OBSERVATIONS INDICATED MOST OF THE RAINFALL WAS IN THE NORTHERN HALF
OF THE REGION...CONCENTRATED IN THE HIGHER TERRAIN. IN THE MODELS
MOIST ISENTROPIC LIFT WAS EXPECTED TO CONTINUE THROUGH 18Z TODAY
ALONG THE 290K ISENTROPE. AT THE SURFACE A WEAK WARM FRONT WAS SEEN
APPROACHING THE N COAST THIS MORNING...HAVING PASSED BUOY 46029
AROUND 13Z. EXPECT THE LIGHT RAIN TO TAPER OFF TO MAINLY OROGRAPHIC
SHOWERS THIS AFTERNOON...AS MOIST LAYER BECOMES SHALLOWER AND
ISENTROPIC LIFT COMES TO AN END.
REMAINDER OF SHORT TERM DISCUSSION UNCHANGED...
A FEW SHOWERS MAY LINGER IN THE CASCADES OVERNIGHT..BUT THE TREND
WILL BE TOWARD DRIER WEATHER FOR FRI. UPPER LEVEL RIDGING REMAINING
IN PLACE OVER THE NE PAC COMBINED WITH THE ADDITIONAL LOW LEVEL
MOISTURE FROM TODAY/S SHOWERS SHOULD CREATE FAVORABLE CONDITIONS FOR
SOME SHALLOW STRATUS OR PATCHY FOG FORMATION EARLY FRI MORNING FOR
THE INTERIOR LOWLANDS AND ALONG THE COAST. OTHERWISE...EXPECT A
RELATIVELY QUIET DAY ON FRI. MOST LOCATIONS SHOULD REMAIN DRY AND
THERE WILL LIKELY BE SOME SUNSHINE AS WELL...PARTICULARLY FOR
SOUTHERN PORTIONS OF THE FCST AREA. LATE IN THE DAY...CLOUDS WILL
BEGIN TO SPREAD IN FROM THE NW AHEAD OF THE NEXT APPROACHING SYSTEM.
THIS NEXT SYSTEM WILL PACK SIGNIFICANTLY MORE PUNCH...BRINGING GUSTY
WINDS ALONG THE COAST...A DECENT SHOT OF RAIN...AND ACCUMULATING
MOUNTAIN SNOW. THIS WILL BE A FAST MOVING SYSTEM...AND THE EXACT
TRACK OF THE SURFACE LOW WILL BE A BIT DIFFICULT TO PIN DOWN UNTIL WE
GET CLOSER TO THE EVENT. THE UPPER LEVEL FORCING WILL BE PROVIDED BY
TWO UPPER LEVEL SHORTWAVES THAT ARE PROGGED TO PHASE OVER THE NE PAC
ON FRI AND WILL PUSH INTO THE PAC NW OVERNIGHT FRI INTO SAT AS A
FAIRLY SHARP UPPER LEVEL TROUGH.
EXPECT RAIN TO BEGIN SPREADING INTO THE NORTHERN COASTAL ZONES FRI
EVENING...THEN PUSH RAPIDLY INLAND OVERNIGHT. THE FCST MODELS
CONTINUE TO INDICATE VERY LITTLE IN THE WAY OF PRE FRONTAL WINDS. BUT
POST FRONTAL NW WINDS WILL LIKELY BRING BREEZY TO GUSTY CONDITIONS TO
THE COASTAL WATERS AND POSSIBLY THE COAST ON SAT MORNING. THE TREND
HAS BEEN TOWARD WEAKENING THESE POST FRONTAL WINDS A BIT. MUCH STILL
DEPENDS ON THE EXACT TRACK OF THE LOW...BUT THINK THAT THERE IS
POTENTIAL TO SEE WIND GUSTS OF 35 TO 45 MPH OVER THE COASTAL WATERS
AND POSSIBLY ALONG THE COAST AS WELL.
SNOW LEVELS WILL REMAIN HIGH AT THE ONSET OF THIS EVENT...WITH RAIN
FALLING FOR ALL BUT THE HIGHEST CASCADE PEAKS OVERNIGHT FRI INTO
EARLY SAT MORNING. HOWEVER THE AIRMASS WILL COOL RAPIDLY AS THE UPPER
LEVEL COLD POOL MOVES ALOFT BETWEEN 12Z AND 18Z SAT. BY LATE MORNING
OR EARLY AFTERNOON...EXPECT THE SNOW LEVEL TO BE DOWN TO THE HIGHER
CASCADE PASSES...THEN DROP DOWN TO THE 2500 TO 3000 FT LEVEL BY SAT
EVENING. THE HEAVIEST PRECIPITATION IS EXPECTED TO FALL BEFORE SNOW
LEVELS DROP...BUT WEST TO NORTHWEST 30 TO 40 KT 850MB FLOW WILL ACT
ON A DEEP CONDITIONALLY UNSTABLE AIRMASS TO PRODUCE AMPLE SHOWERS
OVER THE CASCADES SATURDAY AFTERNOON INTO EARLY SUNDAY. AS A
RESULT...MOTORISTS SHOULD BE PREPARED FOR WINTER LIKE DRIVING
CONDITIONS OVER WILLAMETTE AND SANTIAM PASSES AND AROUND GOVERNMENT
CAMP ALONG HIGHWAY 26 SATURDAY AFTERNOON INTO EARLY SUNDAY. PYLE
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS.
SATURDAY NIGHT THROUGH WEDNESDAY. THE LOW PRESSURE SYSTEM WILL EXIT
THE REGION SUNDAY THOUGH SOME SHOWERS WILL PERSIST BEHIND THE FRONT
WITH THE ONSHORE NEAR-SURFACE FLOW. SNOW SHOULD CONTINUE IN THE
CASCADES SUNDAY ALONG WITH SOME WINDY CONDITIONS. SNOW LEVELS WILL
DROP TO AROUND OR JUST BELOW 3000 FT SUNDAY AS COOL NORTHWESTERLY
FLOW ALOFT BUILDS OVER THE PACIFIC NORTHWEST. SOME SHORTWAVE ENERGY
WILL ENHANCE SHOWER CHANCES EARLY NEXT WEEK AND THE NEXT SYSTEM
SHOULD TUESDAY. WHILE THE FORECAST MODELS EXHIBIT SOME VARIATIONS
WITH RESPECT TO THE FINER DETAILS OF TIMING PERIODS OF PRECIPITATION
THROUGH THE MIDDLE OF NEXT WEEK...IT IS CLEAR THAT WE ARE SHIFTING
TO A MORE SEASONAL TYPE OF PATTERN. HIGHS TEMPERATURES WILL BE
NOTICEABLY COOLER FOR THE FIRST HALF OF NEXT WEEK...AND MAX AND MIN
TEMPERATURES SHOULD EACH RUN SEVERAL DEGREES BELOW NORMAL THROUGH
THE PERIOD. CULLEN
&&
.AVIATION...WEAK WEATHER DISTURBANCE MOVING ACROSS THE AREA THIS
MORNING HAS RESULTED IN SOME MVFR CIGS INLAND WITH AREAS OF LIGHT
RAIN OR DRIZZLE OCCASIONALLY REDUCING VIS TO MVFR. TROUGH MOVES
THROUGH THIS AFTERNOON BUT MVFR CIGS EXPECTED TO RETURN TO MOST
INLAND AREAS OVERNIGHT. EXPECT SOME IFR CIGS ALONG THE COAST AFTER
MIDNIGHT AND LOCAL IFR INLAND DURING THE EARLY MORNING HOURS FRI.
KPDX AND APPROACHES...CIGS WILL REMAIN VFR BUT COULD BE OCCASIONAL
MVFR WITH OCCASIONAL LIGHT RAIN OR DRIZZLE THROUGH 23Z. CONDITIONS
WILL IMPROVE SOME DURING THE EVENING AS TROUGH PASSES TO THE EAST.
EXPECT MVFR CIGS TO RETURN AFTER 12Z. SCHNEIDER
&&
.MARINE...WEAK FRONT SLOW TO PASS INLAND WITH WINDS STILL IN THE
SMALL CRAFT ADVISORY RANGE NEAR SHORE IN THE NORTHERN INLAND
WATERS. HRRR MODEL STILL INDICATING WINDS WILL REMAIN STRONG
ENOUGH FOR A SMALL CRAFT ADVISORY THROUGH 18Z. FRONT WILL WEAKEN
AND MOVE INLAND BY AFTERNOON WITH WINDS DROPPING OFF.
A MUCH STRONGER SYSTEM WILL IMPACT THE WATERS LATE FRIDAY NIGHT
AND SAT. MODELS STILL CAN NOT AGREE ON THE INTENSITY AND STRUCTURE
OF THIS NEXT SYSTEM MAKING FOR A DIFFICULT AND UNCERTAIN FORECAST.
THE GFS CONTINUES TO SHOW A DEEP LOW IN THE GULF WITH STRONG NW
WINDS DEVELOPING BEHIND THE LOW. THIS RESULTS IN MUCH HIGHER SEAS
THAN THE NAM OR ECMWF MODEL WOULD INDICATE. THE OLD ECMWF HAS MORE
OF AN OPEN WAVE WITH THE LOW MOVING INLAND FASTER AND LESS OF A
FETCH TO BUILD HE SEAS. FOR NOW WILL NOT MAKE CHANGES TO THE
CURRENT FORECAST WHICH IS A COMPROMISE BETWEEN MODELS. SCHNEIDER
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 AM PDT THIS MORNING
FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD
OR OUT 10 NM.
&&
$$
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 LA CROSSE WI
600 PM CDT THU OCT 31 2013
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 317 PM CDT THU OCT 31 2013
MAIN FORECAST CONCERNS ARE ON LIGHT RAIN CHANCES TONIGHT AND LATE
FRIDAY AFTERNOON INTO FRIDAY NIGHT.
LATEST WATER VAPOR IMAGERY AND 500 MB RAP ANALYSIS SHOWED A TROUGH
EXTENDING FROM THE UPPER MISSISSIPPI RIVER VALLEY SOUTH THROUGH THE
SOUTHERN PLAINS AND MOVING EAST. AN EMBEDDED SHORTWAVE WAS LIFTING
NORTHEAST THROUGH NORTHERN ILLINOIS INTO SOUTHEAST WISCONSIN.
SURFACE OBSERVATIONS SHOWED LOW PRESSURE OVER NORTHEAST WISCONSIN
WITH A COLD FRONT EXTENDING SOUTH ALONG THE INTERSTATE 39 CORRIDOR
INTO THROUGH NORTH CENTRAL ILLINOIS MOVING EAST. EXTENSIVE CLOUD
COVER NOTED OVER THE REGION THIS AFTERNOON WITH TEMPERATURES
RANGING FROM THE UPPER 30S TO LOWER 40S OVER SOUTHEAST MINNESOTA
TO THE MID 50S OVER CENTRAL WISCONSIN.
THE SURFACE LOW WILL DEEPEN AND SHIFT EAST OVER NORTHERN LOWER
MICHIGAN/EASTERN UPPER MICHIGAN TONIGHT AS THE TROUGH LIFTS INTO THE
GREAT LAKES. LOW LEVEL MOISTURE WILL CONTINUE TO BRING ABUNDANT
CLOUD COVER THE AREA AS WELL AS THE POTENTIAL FOR SOME LIGHT RAIN OR
DRIZZLE LATE TONIGHT INTO EARLY FRIDAY MORNING. A WEAK SHORTWAVE AND
SURFACE TROUGH WILL SLIDE ACROSS CENTRAL WISCONSIN TONIGHT INTO
FRIDAY MORNING AND MAY GENERATE SOME LIGHT RAIN OR DRIZZLE OVER
PORTIONS OF WESTERN INTO CENTRAL WISCONSIN. OTHERWISE...PLAN ON
A CLOUDY AND COOL NIGHT WITH LOWS FALLING INTO THE UPPER 30S TO
LOWER 40S. CLOUDS WILL REMAIN ACROSS THE REGION ON FRIDAY AS
ANOTHER TROUGH DROPS SOUTH OUT OF SOUTHERN MANITOBA/SASKATCHEWAN.
THE TROUGH IS EXPECTED TO SLIDE ACROSS THE UPPER MISSISSIPPI RIVER
VALLEY LATE FRIDAY AFTERNOON INTO FRIDAY NIGHT BRINGING A CHANCE
OF LIGHT RAIN TO THE AREA. GIVEN THE CLOUDS IN PLACE ACROSS THE
REGION ON FRIDAY AND THE PRECIPITATION MOVING IN LATE DECIDED TO
COOL HIGHS A FEW DEGREES ON FRIDAY WITH HIGHS RANGING FROM THE MID
40S OVER NORTH CENTRAL WISCONSIN TO AROUND 50 ACROSS NORTHEAST
IOWA.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 317 PM CDT THU OCT 31 2013
HIGH PRESSURE GRADUALLY BUILDS INTO THE UPPER MISSISSIPPI RIVER
VALLEY ON SATURDAY WITH DECREASING CLOUDS EXPECTED BY LATE
AFTERNOON. AN UPPER RIDGE WILL SLIDE OVER THE AREA ON SUNDAY
PROVIDING MOSTLY SUNNY SKIES. BREEZY SOUTHEAST WINDS WILL DEVELOP ON
SUNDAY AS THE SURFACE HIGH SLIDES OFF OT THE EAST AND A TROUGH
DEVELOPS OVER THE PLAINS. THE OPEN AREAS OF SOUTHEAST MINNESOTA AND
NORTHEAST IOWA WILL SEE THE STRONGEST WINDS WHERE SPEEDS DURING THE
AFTERNOON WILL RANGE FROM THE 15 TO 20 MPH WITH GUSTS TO AROUND 30
MPH. A RIDGE DIGS INTO THE WESTERN CONUS FOR THE START OF THE WORK
WEEK PUSHING A COLD FRONT TOWARD THE AREA FROM THE NORTHERN PLAINS.
ACTIVE SOUTHWEST FLOW SETS UP OVER THE REGION FROM MONDAY INTO
WEDNESDAY WITH SEVERAL ROUNDS OF PRECIPITATION POSSIBLE. RAIN
CHANCES SPREAD BACK INTO THE AREA ON MONDAY AS THE FRONT MOVES INTO
THE UPPER MISSISSIPPI RIVER VALLEY AND STALLS OVER THE FORECAST
AREA. SHORTWAVES WITHIN THE SOUTHWEST FLOW ALOFT WILL INTERACT WITH
THE FRONT AND WILL LIKELY BRING SHOWERS TO THE AREA THROUGH TUESDAY.
FORECAST MODELS ARE IN CLOSE AGREEMENT ON PUSHING THE COLD FRONT
ACROSS THE AREA TUESDAY NIGHT INTO WEDNESDAY AS A STRONGER
SHORTWAVES LIFTS NORTHEAST ACROSS THE AREA...SO WILL GO WITH LIKELY
PRECIPITATION CHANCES. TEMPERATURES COOL BEHIND THE FRONT WEDNESDAY
INTO THURSDAY. HIGHS ON WEDNESDAY ARE EXPECTED TO RANGE FORM THE MID
TO UPPER 40S...THEN COOL INTO THE LOWER 40S FOR THURSDAY. CANNOT
RULE OUT SOME SNOW MIXING IN WITH THE RAIN LATE TUESDAY NIGHT WEST
OF THE MISSISSIPPI RIVER THEN AGAIN LATE WEDNESDAY NIGHT OVER
NORTHEAST IOWA INTO CENTRAL WISCONSIN BEFORE THE PRECIPITATION
DEPARTS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 600 PM CDT THU OCT 31 2013
LOW CIGS WILL PERSIST THROUGH THE NIGHT TIME HOURS - GENERALLY
HOVERING NEAR 1 KFT - AS A LOW PRESSURE SYSTEM EXITS TO THE EAST.
NOT MUCH VSBY RESTRICTIONS INDICATED VIA LATEST SFC OBS...AND DON/T
ANTICIPATED MUCH DEVELOPMENT TONIGHT AS WINDS STAY FAIRLY STIRRED
OUT OF THE WEST/NORTHWEST.
CIGS SHOULD START TO IMPROVE BY MID MORNING FRIDAY...AND COULD GET A
BUMP INTO VFR BY 18Z. WILL PLAY THIS MORE PESSIMISTIC...WAITING
UNTIL LATER IN THE AFTERNOON. FALL/WINTER CAN BE NOTORIOUS FOR
HANGING ONTO LOW CIGS LONGER THAN THE MODELS WOULD SUGGEST.
BITS OF UPPER LEVEL ENERGY AND A SFC TROUGH COULD SPARK A FEW -SHRA
LATE TONIGHT INTO FRIDAY. BETTER CHANCES LOOK TO BE ALONG I-94
NORTH/EAST...BUT CAN/T COMPLETELY RULE OUT A -SHRA PASSING
ACROSS KRST/KLSE. NOT ENOUGH CONFIDENCE TO ADD TO THE FORECAST...BUT
SOMETHING TO WATCH. DON/T THINK THERE WOULD BE A SIGNIFICANT IMPACT
ON CIGS/VSBY IF IT OCCURRED.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM....WETENKAMP
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
317 PM CDT THU OCT 31 2013
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 317 PM CDT THU OCT 31 2013
MAIN FORECAST CONCERNS ARE ON LIGHT RAIN CHANCES TONIGHT AND LATE
FRIDAY AFTERNOON INTO FRIDAY NIGHT.
LATEST WATER VAPOR IMAGERY AND 500 MB RAP ANALYSIS SHOWED A TROUGH
EXTENDING FROM THE UPPER MISSISSIPPI RIVER VALLEY SOUTH THROUGH THE
SOUTHERN PLAINS AND MOVING EAST. AN EMBEDDED SHORTWAVE WAS LIFTING
NORTHEAST THROUGH NORTHERN ILLINOIS INTO SOUTHEAST WISCONSIN.
SURFACE OBSERVATIONS SHOWED LOW PRESSURE OVER NORTHEAST WISCONSIN
WITH A COLD FRONT EXTENDING SOUTH ALONG THE INTERSTATE 39 CORRIDOR
INTO THROUGH NORTH CENTRAL ILLINOIS MOVING EAST. EXTENSIVE CLOUD
COVER NOTED OVER THE REGION THIS AFTERNOON WITH TEMPERATURES
RANGING FROM THE UPPER 30S TO LOWER 40S OVER SOUTHEAST MINNESOTA
TO THE MID 50S OVER CENTRAL WISCONSIN.
THE SURFACE LOW WILL DEEPEN AND SHIFT EAST OVER NORTHERN LOWER
MICHIGAN/EASTERN UPPER MICHIGAN TONIGHT AS THE TROUGH LIFTS INTO THE
GREAT LAKES. LOW LEVEL MOISTURE WILL CONTINUE TO BRING ABUNDANT
CLOUD COVER THE AREA AS WELL AS THE POTENTIAL FOR SOME LIGHT RAIN OR
DRIZZLE LATE TONIGHT INTO EARLY FRIDAY MORNING. A WEAK SHORTWAVE AND
SURFACE TROUGH WILL SLIDE ACROSS CENTRAL WISCONSIN TONIGHT INTO
FRIDAY MORNING AND MAY GENERATE SOME LIGHT RAIN OR DRIZZLE OVER
PORTIONS OF WESTERN INTO CENTRAL WISCONSIN. OTHERWISE...PLAN ON
A CLOUDY AND COOL NIGHT WITH LOWS FALLING INTO THE UPPER 30S TO
LOWER 40S. CLOUDS WILL REMAIN ACROSS THE REGION ON FRIDAY AS
ANOTHER TROUGH DROPS SOUTH OUT OF SOUTHERN MANITOBA/SASKATCHEWAN.
THE TROUGH IS EXPECTED TO SLIDE ACROSS THE UPPER MISSISSIPPI RIVER
VALLEY LATE FRIDAY AFTERNOON INTO FRIDAY NIGHT BRINGING A CHANCE
OF LIGHT RAIN TO THE AREA. GIVEN THE CLOUDS IN PLACE ACROSS THE
REGION ON FRIDAY AND THE PRECIPITATION MOVING IN LATE DECIDED TO
COOL HIGHS A FEW DEGREES ON FRIDAY WITH HIGHS RANGING FROM THE MID
40S OVER NORTH CENTRAL WISCONSIN TO AROUND 50 ACROSS NORTHEAST
IOWA.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 317 PM CDT THU OCT 31 2013
HIGH PRESSURE GRADUALLY BUILDS INTO THE UPPER MISSISSIPPI RIVER
VALLEY ON SATURDAY WITH DECREASING CLOUDS EXPECTED BY LATE
AFTERNOON. AN UPPER RIDGE WILL SLIDE OVER THE AREA ON SUNDAY
PROVIDING MOSTLY SUNNY SKIES. BREEZY SOUTHEAST WINDS WILL DEVELOP ON
SUNDAY AS THE SURFACE HIGH SLIDES OFF OT THE EAST AND A TROUGH
DEVELOPS OVER THE PLAINS. THE OPEN AREAS OF SOUTHEAST MINNESOTA AND
NORTHEAST IOWA WILL SEE THE STRONGEST WINDS WHERE SPEEDS DURING THE
AFTERNOON WILL RANGE FROM THE 15 TO 20 MPH WITH GUSTS TO AROUND 30
MPH. A RIDGE DIGS INTO THE WESTERN CONUS FOR THE START OF THE WORK
WEEK PUSHING A COLD FRONT TOWARD THE AREA FROM THE NORTHERN PLAINS.
ACTIVE SOUTHWEST FLOW SETS UP OVER THE REGION FROM MONDAY INTO
WEDNESDAY WITH SEVERAL ROUNDS OF PRECIPITATION POSSIBLE. RAIN CHANCES
SPREAD BACK INTO THE AREA ON MONDAY AS THE FRONT MOVES INTO THE
UPPER MISSISSIPPI RIVER VALLEY AND STALLS OVER THE FORECAST AREA.
SHORTWAVES WITHIN THE SOUTHWEST FLOW ALOFT WILL INTERACT WITH THE
FRONT AND WILL LIKELY BRING SHOWERS TO THE AREA THROUGH TUESDAY.
FORECAST MODELS ARE IN CLOSE AGREEMENT ON PUSHING THE COLD FRONT
ACROSS THE AREA TUESDAY NIGHT INTO WEDNESDAY AS A STRONGER
SHORTWAVES LIFTS NORTHEAST ACROSS THE AREA...SO WILL GO WITH
LIKELY PRECIPITATION CHANCES. TEMPERATURES COOL BEHIND THE FRONT
WEDNESDAY INTO THURSDAY. HIGHS ON WEDNESDAY ARE EXPECTED TO RANGE
FORM THE MID TO UPPER 40S...THEN COOL INTO THE LOWER 40S FOR
THURSDAY. CANNOT RULE OUT SOME SNOW MIXING IN WITH THE RAIN LATE
TUESDAY NIGHT WEST OF THE MISSISSIPPI RIVER THEN AGAIN LATE
WEDNESDAY NIGHT OVER NORTHEAST IOWA INTO CENTRAL WISCONSIN BEFORE
THE PRECIPITATION DEPARTS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1234 PM CDT THU OCT 31 2013
CEILINGS WILL BECOME MVFR BRIEFLY THIS AFTERNOON AND THEN BECOME
IFR THIS EVENING AND REMAIN THAT WAY THROUGH MUCH OF FRIDAY
MORNING. ON THE RIDGE TOPS AND HIGHER ELEVATIONS OF SOUTHEAST
MINNESOTA AND NORTHEAST IOWA...CEILINGS WILL LIKELY ONLY BE A
COUPLE OF HUNDRED FEET. THIS INCLUDES KRST BETWEEN 01.06Z AND
01.16Z.
AS FAR AS VISIBILITIES...IT LOOKS LIKE THE WINDS WILL KEEP THINGS
STIRRED UP ENOUGH THAT THERE SHOULD BE NO RESTRICTIONS TONIGHT AND
FRIDAY MORNING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1235 PM CDT THU OCT 31 2013
.UPDATE...
ISSUED AT 1200 PM CDT THU OCT 31 2013
DURING THE PAST HOUR...VISIBILITIES HAVE BEEN RAPIDLY IMPROVING
ACROSS THE AREA. THIS TREND IS EXPECTED TO CONTINUE THIS
AFTERNOON. AS A RESULT...THE DENSE FOG ADVISORY HAS BEEN ALLOWED
TO EXPIRE.
UPDATE ISSUED AT 901 AM CDT THU OCT 31 2013
WITH VISIBILITIES RUNNING AROUND A QUARTER MILE...EXPANDED THE
DENSE FOG ADVISORY SOUTH TO VERNON COUNTY. ALSO DECIDED TO EXTEND
IT UNTIL NOON. WITH THE SREF AND HRRR SHOWING THAT THE
VISIBILITIES WILL IMPROVE RAPIDLY BETWEEN 31.15Z AND 31.18Z...DO
NOT ANTICIPATE HAVING TO EXTEND THIS ADVISORY INTO THE AFTERNOON.
&&
.SHORT TERM...(TODAY AND TONIGHT)
213 AM CDT THU OCT 31 2013
MAIN FOCUS DURING THE SHORT TERM PERIOD IS THE PRECIPITATION AS THE
LOW PRESSURE SYSTEM TRAVERSES THE AREA. ALSO WATCHING FOG TRENDS
WITH DENSE FOG ACROSS PARTS OF THE REGION. 07Z SURFACE ANALYSIS
SHOWS THE LOW CENTER SOMEWHERE BETWEEN KRST AND KDEH...MOVING EAST.
FRONTAL BOUNDARY TRAILING SOUTH FROM THE LOW THROUGH CENTRAL IA.
RADAR LOOP SHOWS SHOWERS AND A FEW EMBEDDED THUNDERSTORMS AHEAD OF
THE LOW...WITH WIDESPREAD LIGHT RETURN ALONG AND BEHIND...
INDICATIVE OF DRIZZLE OR VERY LIGHT RAIN. SURFACE OBSERVATIONS
SHOW DENSE FOG OVER NORTHERN WI...WHERE A DENSE FOG ADVISORY
REMAINS IN EFFECT. THICK FOG IS ALSO OCCURRING ALONG THE FRONT AS
IT MOVES EAST.
IT WILL TAKE SOME TIME...BUT THE MAIN SHORT WAVE TROUGH AND LOW
SYSTEM WILL TRACK NORTHEAST OUT OF THE AREA BY TONIGHT. WEAK FLOW
AND WEAK LIFT WILL KEEP THE THREAT FOR VERY LIGHT PRECIPITATION
AROUND THROUGH MUCH OF THE DAY...SO WILL HANG ONTO THE LOW CHANCES
UNTIL THE EVENING HOURS. COLD ADVECTION BEHIND THE FRONT WILL KEEP
TEMPERATURES FROM MOVING MUCH. IN FACT...THEY SHOULD FALL FOR A
GOOD PORTION OF THE DAY...WITH PERHAPS A FEW DEGREES OF AN UPWARD
TICK DURING THE AFTERNOON. TONIGHT SHOULD SEE THE MERCURY DIP INTO
THE 30S. IT COULD GET A BIT COOLER IF THE CLOUDS BREAK UP MORE...
SO WILL HAVE TO WATCH THAT TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
213 AM CDT THU OCT 31 2013
A FAST-MOVING SHORT WAVE TROUGH WILL ZIP SOUTHEAST FROM ALBERTA
AND SASKATCHEWAN INTO MN/IA BY FRIDAY. MOISTURE WILL BE LIMITED...
BUT THERE WILL BE AMPLE LIFT AND SOMEWHAT STEEP LAPSE RATES WITH
THE COOLER AIR IN PLACE BEHIND THE DEPARTING SYSTEM. ANTICIPATE
SOME SCATTERED SHOWERS TO DEVELOP AND MOVE THROUGH THE AREA FROM
LATE FRIDAY AFTERNOON INTO FRIDAY NIGHT. DO NOT EXPECT RAIN TO
AMOUNT TO TOO MUCH. WEAK CHANNELED VORTICITY WILL BE DROPPING INTO
THE BACK SIDE OF THE DEEPENING LONG WAVE TROUGH OVER THE OHIO
VALLEY...AND THIS COULD PROVIDE SOME WEAK SUPPORT TO GENERATE A
FEW SHOWERS OVER PARTS OF WI DURING THE DAY SATURDAY. AGAIN...IF
THIS DOES HAPPEN...DO NOT EXPECT IT TO AMOUNT TO VERY MUCH. `
HIGH PRESSURE THEN BUILDS IN...PROVIDING FOR A COOL NIGHT SATURDAY
NIGHT AND A COOL BUT PLEASANT DAY ON SUNDAY. BUT THE UNSETTLED
WEATHER PATTERN RESULTS IN ANOTHER LONG WAVE TROUGH DIGGING INTO
THE ROCKIES ON MONDAY...WHICH FORMS A STRONG LOW PRESSURE SYSTEM
ACROSS THE DAKOTAS AND MANITOBA. THIS ONE LOOKS TO REMAIN NORTH OF
THE REGION...AS IT TRACKS THROUGH WESTERN ONTARIO INTO JAMES BAY.
BUT THE TRAILING COLD FRONT WILL MOVE THROUGH THE REGION MONDAY...
BRINGING ANOTHER CHANCE FOR SHOWERS. AND ANOTHER SHORT WAVE TROUGH
ROUNDING THE BASE OF THE MAIN TROUGH WILL EJECT UP ACROSS THE
PLAINS AND TOWARD THE GREAT LAKES REGION FOR TUESDAY INTO
WEDNESDAY. OVERALL TEMPERATURES LOOK TO BE NEAR NORMAL...WITH NO
REAL CONNECTION TO THE ARCTIC AIR SEEN IN THE FORESEEABLE FUTURE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1234 PM CDT THU OCT 31 2013
CEILINGS WILL BECOME MVFR BRIEFLY THIS AFTERNOON AND THEN BECOME
IFR THIS EVENING AND REMAIN THAT WAY THROUGH MUCH OF FRIDAY
MORNING. ON THE RIDGE TOPS AND HIGHER ELEVATIONS OF SOUTHEAST
MINNESOTA AND NORTHEAST IOWA...CEILINGS WILL LIKELY ONLY BE A
COUPLE OF HUNDRED FEET. THIS INCLUDES KRST BETWEEN 01.06Z AND
01.16Z.
AS FAR AS VISIBILITIES...IT LOOKS LIKE THE WINDS WILL KEEP THINGS
STIRRED UP ENOUGH THAT THERE SHOULD BE NO RESTRICTIONS TONIGHT AND
FRIDAY MORNING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...BOYNE
SHORT TERM...MW
LONG TERM...MW
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1202 PM CDT THU OCT 31 2013
.UPDATE...THIS AFTERNOON
ISSUED AT 1200 PM CDT THU OCT 31 2013
DURING THE PAST HOUR...VISIBILITIES HAVE BEEN RAPIDLY IMPROVING
ACROSS THE AREA. THIS TREND IS EXPECTED TO CONTINUE THIS
AFTERNOON. AS A RESULT...THE DENSE FOG ADVISORY HAS BEEN ALLOWED
TO EXPIRE.
UPDATE ISSUED AT 901 AM CDT THU OCT 31 2013
WITH VISIBILITIES RUNNING AROUND A QUARTER MILE...EXPANDED THE
DENSE FOG ADVISORY SOUTH TO VERNON COUNTY. ALSO DECIDED TO EXTEND
IT UNTIL NOON. WITH THE SREF AND HRRR SHOWING THAT THE
VISIBILITIES WILL IMPROVE RAPIDLY BETWEEN 31.15Z AND 31.18Z...DO
NOT ANTICIPATE HAVING TO EXTEND THIS ADVISORY INTO THE AFTERNOON.
&&
.SHORT TERM...(TODAY AND TONIGHT)
213 AM CDT THU OCT 31 2013
MAIN FOCUS DURING THE SHORT TERM PERIOD IS THE PRECIPITATION AS THE
LOW PRESSURE SYSTEM TRAVERSES THE AREA. ALSO WATCHING FOG TRENDS
WITH DENSE FOG ACROSS PARTS OF THE REGION. 07Z SURFACE ANALYSIS
SHOWS THE LOW CENTER SOMEWHERE BETWEEN KRST AND KDEH...MOVING EAST.
FRONTAL BOUNDARY TRAILING SOUTH FROM THE LOW THROUGH CENTRAL IA.
RADAR LOOP SHOWS SHOWERS AND A FEW EMBEDDED THUNDERSTORMS AHEAD OF
THE LOW...WITH WIDESPREAD LIGHT RETURN ALONG AND BEHIND...
INDICATIVE OF DRIZZLE OR VERY LIGHT RAIN. SURFACE OBSERVATIONS
SHOW DENSE FOG OVER NORTHERN WI...WHERE A DENSE FOG ADVISORY
REMAINS IN EFFECT. THICK FOG IS ALSO OCCURRING ALONG THE FRONT AS
IT MOVES EAST.
IT WILL TAKE SOME TIME...BUT THE MAIN SHORT WAVE TROUGH AND LOW
SYSTEM WILL TRACK NORTHEAST OUT OF THE AREA BY TONIGHT. WEAK FLOW
AND WEAK LIFT WILL KEEP THE THREAT FOR VERY LIGHT PRECIPITATION
AROUND THROUGH MUCH OF THE DAY...SO WILL HANG ONTO THE LOW CHANCES
UNTIL THE EVENING HOURS. COLD ADVECTION BEHIND THE FRONT WILL KEEP
TEMPERATURES FROM MOVING MUCH. IN FACT...THEY SHOULD FALL FOR A
GOOD PORTION OF THE DAY...WITH PERHAPS A FEW DEGREES OF AN UPWARD
TICK DURING THE AFTERNOON. TONIGHT SHOULD SEE THE MERCURY DIP INTO
THE 30S. IT COULD GET A BIT COOLER IF THE CLOUDS BREAK UP MORE...
SO WILL HAVE TO WATCH THAT TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
213 AM CDT THU OCT 31 2013
A FAST-MOVING SHORT WAVE TROUGH WILL ZIP SOUTHEAST FROM ALBERTA
AND SASKATCHEWAN INTO MN/IA BY FRIDAY. MOISTURE WILL BE LIMITED...
BUT THERE WILL BE AMPLE LIFT AND SOMEWHAT STEEP LAPSE RATES WITH
THE COOLER AIR IN PLACE BEHIND THE DEPARTING SYSTEM. ANTICIPATE
SOME SCATTERED SHOWERS TO DEVELOP AND MOVE THROUGH THE AREA FROM
LATE FRIDAY AFTERNOON INTO FRIDAY NIGHT. DO NOT EXPECT RAIN TO
AMOUNT TO TOO MUCH. WEAK CHANNELED VORTICITY WILL BE DROPPING INTO
THE BACK SIDE OF THE DEEPENING LONG WAVE TROUGH OVER THE OHIO
VALLEY...AND THIS COULD PROVIDE SOME WEAK SUPPORT TO GENERATE A
FEW SHOWERS OVER PARTS OF WI DURING THE DAY SATURDAY. AGAIN...IF
THIS DOES HAPPEN...DO NOT EXPECT IT TO AMOUNT TO VERY MUCH. `
HIGH PRESSURE THEN BUILDS IN...PROVIDING FOR A COOL NIGHT SATURDAY
NIGHT AND A COOL BUT PLEASANT DAY ON SUNDAY. BUT THE UNSETTLED
WEATHER PATTERN RESULTS IN ANOTHER LONG WAVE TROUGH DIGGING INTO
THE ROCKIES ON MONDAY...WHICH FORMS A STRONG LOW PRESSURE SYSTEM
ACROSS THE DAKOTAS AND MANITOBA. THIS ONE LOOKS TO REMAIN NORTH OF
THE REGION...AS IT TRACKS THROUGH WESTERN ONTARIO INTO JAMES BAY.
BUT THE TRAILING COLD FRONT WILL MOVE THROUGH THE REGION MONDAY...
BRINGING ANOTHER CHANCE FOR SHOWERS. AND ANOTHER SHORT WAVE TROUGH
ROUNDING THE BASE OF THE MAIN TROUGH WILL EJECT UP ACROSS THE
PLAINS AND TOWARD THE GREAT LAKES REGION FOR TUESDAY INTO
WEDNESDAY. OVERALL TEMPERATURES LOOK TO BE NEAR NORMAL...WITH NO
REAL CONNECTION TO THE ARCTIC AIR SEEN IN THE FORESEEABLE FUTURE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 704 AM CDT THU OCT 31 2013
LIFR VIS/CIGS CURRENTLY OCCURRING ACROSS MUCH OF THE REGION AND AT
THE TAF SITES WITH THE MAIN INITIAL QUESTION FOR THE FORECAST
BEING WHEN THESE CONDITIONS MAY IMPROVE. CALM WINDS AND HIGH
RELATIVE HUMIDITY ASSOCIATED WITH A LOW PRESSURE SYSTEM CENTERED
OVER THE REGION HAS LED TO THIS FOG FORMATION. THE COLD FRONT
ASSOCIATED WITH THE LOW HAS GONE THROUGH RST AND WILL GO THROUGH
LSE BY MID MORNING. WHILE CEILINGS STAY IFR OR WORSE AFTER THE
FRONT COMES THROUGH...THE VISIBILITY AT LEAST IMPROVES ABOVE
1/4SM. THE IFR LOOKS LIKE IT COULD HOLD ON THROUGH MUCH OF THE DAY
THOUGH THERE HAS BEEN SOME IMPROVEMENT TO MVFR ACROSS SOUTH
CENTRAL MINNESOTA ALREADY. PLAYED IT PESSIMISTIC AS THE SURFACE
LOW WILL NOT TRACK TO FAST TO THE EAST AND THE MAIN UPPER LEVEL
TROUGH IS STILL OFF TO THE WEST. CONDITIONS WILL AT LEAST REMAIN
MVFR THROUGH TOMORROW MORNING AS A SECONDARY TROUGH COMES THROUGH
THE REGION TONIGHT AND HELPS TO KEEP SOME LOW LEVEL MOISTURE
AROUND. THERE COULD BE SOME LIGHT RAIN THAT OCCURS WITH THIS
FEATURE AS WELL...BUT THE BETTER FORCING LOOKS LIKE IT STAYS JUST
NORTH OF THE TAF SITES.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...BOYNE
SHORT TERM...MW
LONG TERM...MW
AVIATION...HALBACH