Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/11/12
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1109 AM MST FRI NOV 9 2012
.UPDATE...WILL BE MAKING SOME GENERALLY SMALL CHANGES...A LITTLE
COOLER FROM NORTH DENVER NORTHWARD AS MIXING LIMITED IN THIS AREA
WITH LIGHT NORTH TO NORTHEAST WINDS. MUCH MILDER SOUTH OF DENVER
AND FARTHER TO THE EAST. MILD IN THE MOUNTAINS WITH A SLIGHT
DECREASE IN THE PRECIPITATION POSSIBILITIES THERE.
&&
.AVIATION...KIND OF RARE TOTALLY CALM WIND AT ALL THE LLWS SITES
FOR DIA THIS MORNING FOR AWHILE. KEPT A LIGHT ENE WIND FOR TODAY
BUT WILL NEED TO WATCH AS THERE ARE STRONGER WSW WINDS TO OUR
SOUTH. A NICE FINE LINE ON RADAR MARKS THIS BOUNDARY. HRRR WINDS
KEEP THIS TO THE SOUTH UNTIL THIS EVENING AND OTHER MODELS
GENERALLY AGREE BUT WILL KEEP AN EYE ON IT.
&&
.PREV DISCUSSION... /ISSUED 407 AM MST FRI NOV 9 2012/
SHORT TERM...THINGS ARE STILL ON COURSE FOR THE LAST WARM DAY OF
THE CURRENT STRETCH ACROSS NORTHEAST COLORADO. MODERATE SOUTHWEST
FLOW ALOFT WILL CONTINUE OVER THE STATE TODAY AS A VIGOROUS UPPER
TROUGH MOVES INTO THE GREAT BASIN. MOISTURE AHEAD OF THIS TROUGH
WILL BE MOVING OVER COLORADO THROUGH TODAY...BUT EASTERN COLORADO
SHOULD ONLY SEE HIGH LEVEL CLOUDINESS. DEEPER MOISTURE WILL REACH
THE MOUNTAINS EARLY THIS EVENING...WITH AREAS OF RAIN AND SNOW
DEVELOPING AND THEN CHANGING TO SNOW BY MIDNIGHT. THROUGH 12Z
TOMORROW MORNING...THE MOUNTAINS SHOULD BE THE ONLY AREAS TO
RECEIVE ANY PRECIPITATION. AT THE SURFACE...MODELS ARE NOW SHOWING
THE STRONGEST SURFACE CYCLOGENESIS OVER SOUTHERN WYOMING THROUGH
06Z AND THEN DROPPING INTO NORTHEAST COLORADO BY 12Z BEFORE MOVING
INTO WESTERN NEBRASKA. AS THE SURFACE DEVELOPMENT REMAINS TO OUR
NORTH...FLOW OFF THE MOUNTAINS AND FRONT RANGE FOOTHILLS WILL BE
DOWNSLOPING AND MAINLY DRY. WINDS ON THE PLAINS SHOULD REMAIN OUT
OF THE SOUTH. ANY SIGNIFICANT COOLING TO THE AIRMASS WILL NOT
OCCUR UNTIL AFTER THE SURFACE LOW DROPS INTO NORTHEAST COLORADO.
THAT WILL LEAVE US WITH UNSEASONABLY WARM TEMPERATURES AGAIN
TODAY...IN SPITE OF PERIODS OF MID AND HIGH LEVEL CLOUDINESS. LOW
TEMPERATURES TONIGHT WILL ALSO BE MODERATED BY THE DOWNSLOPING
WINDS FEEDING INTO THE DEVELOPING SURFACE LOW TO OUR NORTH. MODEL
QPF FORECASTS IN THE MOUNTAINS ARE PRETTY LIGHT THROUGH 12Z SO NO
HIGHLIGHTS WILL BE NEEDED FOR THE FIRST TWO PERIODS OF THE
FORECAST.
LONG TERM...AN UPPER LEVEL TROUGH WILL MOVE ACROSS THE RGN SAT
INTO SUN. THE FLOW ALOFT WILL BE SWLY ON SAT AND THEN BECOME MORE
NWLY LATE SAT NIGHT INTO SUN AS THE TROUGH AXIS MOVES ACROSS.
THERE WILL BE PLENTY OF MOISTURE IN THE MTNS ALONG WITH DECENT
INSTABILITY ALONG WITH SOME MINOR QG ASCENT. THUS WILL SEE SOME
SNOW WITH THE BEST ACCUMULATIONS THRU SAT AFTN IN ZN 31 WHERE
AMOUNTS MAY REACH ADVISORY CRITERIA. BY SAT NIGHT INTO SUN AS THE
FLOW ALOFT BECOMES MORE NWLY THE REST OF THE MTNS WILL RECEIVE
SOME ACCUMULATIONS WITH AMOUNTS GENERALLY BLO ADVISORY CRITERIA.
EAST OF THE MTNS THERE ARE LARGE DIFFERENCES BETWEEN THE NAM...GFS
AND ECMWF WITH RESPECT TO HOW MUCH PCPN WILL OCCUR. THE GFS AND TO
SOME EXTENT THE ECMWF SHOW BETTER UPSLOPE COMPONENT FM LATE SAT
AFTN THRU SAT NIGHT WITH DECENT MOISTURE WHILE THE NAM IS DRIER
AND HAS MORE OF A DOWNSLOPE COMPONENT. AS A RESULT THE ECMWF AND
GFS HAVE MORE PCPN WHILE THE NAM BASICALLY HAS NO PCPN EXCEPT FOR
A SMALL AREA OVER THE NERN PLAINS. CONSIDERING THE POSITION OF THE
UPPER LEVEL JET AND STEEP LAPSE RATES NR 9 C/KM SAT EVENING ALONG
WITH POTENTIAL FOR BANDED PCPN I FIND IT HARD TO BELIEVE THERE
WILL NOT BE ANY PCPN AS NAM DEPICTS. THUS WILL KEEP LIKELY POPS IN
THE FCST SAT NIGHT OVER NERN CO. IF SOUNDINGS ARE MOIST ADIABATIC
AS SHOWN BY GFS THEN A BURST OF HEAVIER CONVECTIVE SNOW WILL
CERTAINLY BE POSSIBLE ACROSS PORTIONS OF NERN CO. THE GFS HAS A
BULLSEYE OVER DENVER WHILE THE ECMWF IS A BIT FURTHER EAST. AS FOR
TEMPS TIMING OF FNT COMING INTO NERN CO WILL HAVE AN AFFECT ON
HIGHS. RIGHT NOW THE GFS HAS IT MOVING INTO DENVER AROUND 18Z AND
THEN STALLING OVER THE PLAMER DIVIDE DUE TO STRONGER SWLY LOW LVL
FLOW. NORTH OF THE FNT HIGHS WILL ONLY BE IN THE 40S WHILE SOUTH
OF IT HIGHS COULD REACH THE LOWER TO MID 60S ACROSS LINCOLN
COUNTY.
BY SUN AFTN THE UPPER LEVEL TROUGH WILL MOVE AWAY FM THE AREA WITH
NWLY FLOW ALOFT. MOISTURE WILL LINGER IN THE MTNS THRU SUN EVENING
SO WILL KEEP SOME POPS IN THRU MIDNIGHT. ACROSS NERN CO IT LOOKS
LIKE PCPN SHOULD END SUN MORNING. HIGHS ON SUN WILL BE COLD WITH
READINGS MAINLY IN THE UPPER 20S TO LOWER 30S ACROSS NERN CO. FOR
MON DRY NWLY FLOW ALOFT WILL BE OVER THE AREA WITH NO PCPN
EXPECTED. HIGHS SHOULD RISE BACK INTO THE LOWER TO MID 40S OVER
THE PLAINS.
FOR TUE THE FLOW ALOFT WILL BECOME MORE WLY WITH DRY CONDITIONS.
TEMPS SHOULD CONTINUE TO RISE A FEW MORE DEGREES WITH READINGS IN
THE UPPER 40S TO LOWER 50S ACROSS NERN CO. BY WED THE FLOW ALOFT
WILL BECOME MORE SWLY AS ANOTHER UPPER LEVEL TROUGH DEVELOPS OVER
THE WRN US. SOME MID AND HIGH LEVEL MOISTURE WILL SPREAD ACROSS
THE AREA BUT NO PCPN IS EXPECTED. HIGHS SHOULD RISE BACK INTO THE
50S OVER NERN CO BASED ON LATEST 850-700 MB TEMPS.
BY THU THERE ARE LARGE DIFFERENCES BETWEEN THE ECMWF AND GFS IN
HANDLING OF THE NEXT UPPER LEVEL TROUGH. THE GFS MOVES THE NEXT
TROUGH ACROSS THE AREA LATE THU INTO EARLY FRI WHILE THE ECMWF IS
A DAY SLOWER WITH THIS FEATURE. AT THIS POINT HARD TO SAY WHICH
SOLUTION IS RIGHT SO WILL JUST MENTION A SLIGHT CHC OF SHOWERS IN
THE MTNS AND KEEP HIGHS NEAR SEASONAL LEVELS.
AVIATION...DENVER AREA AIRPORTS WILL SEE INCREASING CLOUDS ALOFT
THROUGH THE DAY...BUT CEILINGS SHOULD REMAIN WELL ABOVE 10
THOUSAND FEET UNTIL LATER TONIGHT. WINDS WILL HAVE A SOUTHERLY
COMPONENT THROUGH TONIGHT AS A SURFACE LOW PRESSURE AREA IS
EXPECTED TO INTENSIFY OVER SOUTHERN WYOMING LATER TODAY. CEILINGS
WILL BEGIN TO DECREASE DURING THE PRE-DAWN HOURS TOMORROW MORNING
WITH PRECIPITATION DEVELOPING AFTER 12Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 5 AM SATURDAY TO 5 AM MST SUNDAY
FOR COZ031.
&&
$$
SHORT TERM...SZOKE
LONG TERM....RPK
AVIATION...SZOKE
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
345 AM EST FRI NOV 9 2012
.DISCUSSION...
TODAY-TONIGHT...A LARGE H100-H70 HI PRES RIDGE EXTENDING FROM THE
BAY OF CAMPECHE TO THE GREAT LAKES REGION WILL DRIFT E/NE TODAY AS A
SHORT WAVE TROF OFF THE ERN SEABOARD PUSHES INTO THE OPEN ATLC. THU
EVNG RAOB SOUNDINGS SHOW A VERY DRY/STABLE AIRMASS OVERHEAD WITH A
25C SUBSIDENCE INVERSION IN THE H85-H60 LYR ACRS CENTRAL FL...PWAT
VALUES ARND 0.3".
LATEST RAP ANALYSIS SHOWS A TIGHT RH GRADIENT IN THE H100-H85 LYR
EXTENDING FROM THE CAPE TO LAKE OKEECHOBEE...VALUES AOB 35PCT TO THE
NW AND AOA 65PCT TO THE SE. SFC/TRANSPORT WINDS ARE EXPECTED TO VEER
TO THE NE BY MIDDAY AFTN AS THE ANTICYCLONE PUSHES E. HOWEVER...THIS
WILL ONLY BRING THE WINDS INTO PARALLEL ALIGNMENT WITH THE RH
GRADIENT...THUS LIMITING THE POTENTIAL FOR AIRMASS MODIFICATION TO
THE COASTAL COUNTIES. WINDS WILL CONTINUE TO VEER TO THE E/NE
OVERNIGHT WHICH SHOULD PROVIDE ENOUGH WRLY PUSH TO BEGIN MODIFYING
THE DRY AIR OVER THE INTERIOR.
WILL KEEP MOSUNNY SKIES OVER THE INTERIOR THRU THE AFTN...PSUNNY
ALONG THE COAST...PCLDY ACRS THE SRN CWA/MCLR NRN CWA OVERNIGHT. MAX
TEMPS WILL BEGIN TO REBOUND FROM THE RECENT COOL DOWN...THOUGH THE
NRLY WIND COMPONENT WILL MAINTAIN ENOUGH COOL ADVECTION TO KEEP
TEMPS IN THE L/M70S...ARND 5F BLO CLIMO. AS WINDS BECOME MORE NORMAL
TO THE COAST OVERNIGHT...MIN TEMPS ALONG AND E OF THE I-95 CORRIDOR
WILL HOLD IN THE M-U50S...L/M50S OVER THE INTERIOR.
SAT-SUN...RIDGE ALOFT WILL AMPLIFY NEAR THE EAST COAST IN RESPONSE
TO TROF DEEPENING THROUGH THE PLAINS. SURFACE HIGH PRESSURE WILL BE
REINFORCED TO THE NORTH...WITH WINDS VEERING FROM THE NORTHEAST TO
EAST AND PICKING UP A BIT AS IT DOES SO. RIDGE ALOFT AND VEERING LOW
LEVEL FLOW WILL ALLOW TEMPERATURES TO MODERATE WITH HIGHS SATURDAY
MID 70S COAST/UPPER 70S INLAND...AND UPPER 70S COAST/AROUND 80
INLAND ON SUNDAY. OVERNIGHT MINS LOW/MID 50S SAT MORN...RISING TO
UPPER 50S/LOWER 60S INLAND AND VOLUSIA...MID/UPPER 60S SPACE AND
TREASURE COASTS SUNDAY. SHALLOW MOISTURE DEPTH AND PERSISTENCE OF
INVERSION ALOFT EXPECTED TO KEEP POPS BELOW MENTIONABLE VALUES.
MON-THU...SURFACE RIDGE THE NORTH WILL DRIFT EASTWARD OVER THE
ATLANTIC EARLY NEXT WEEK AHEAD OF A FRONT THAT WILL MOVE DOWN THE
PENINSULA IN THE TUE-TUE NIGHT TIME FRAME. WILL KEEP CONTINUITY
INDICATING A LOW RAIN CHANCE WITH THE FRONT. ONLY SLIGHT COOLING
EXPECTED BEHIND THE FRONT BEFORE FLOW QUICKLY VEERS ONSHORE AGAIN
WED INTO THURS.
&&
.AVIATION...THRU 10/12Z...VFR ALL SITES.
&&
.MARINE...TODAY-TONIGHT...HIGH PRES RIDGE OVER THE GOMEX/DEEP SOUTH
WILL GENERATE A MODERATE N/NE BREEZE ACRS THE LCL ATLC THIS AFTN...
BCMG E/NE OVERNIGHT AS THE RIDGE DRIFTS TOWARD THE ERN SEABOARD. THE
NRLY WIND COMPONENT WILL COMBINE WITH THE SRLY COMPONENT OF THE GULF
STREAM TO GENERATE SEAS UP TO 7FT IN THE GULF STREAM. HOWEVER...
LATEST OBS FROM THE LCL DATA BUOY/C-MAN NETWORK SHOW THE THE LCL
PGRAD IS NOT TIGHT ENOUGH GENERATE WINDS ABV 15KTS. WILL EXTEND THE
SCA THRU SUNSET TONIGHT BUT FOR SEAS ONLY...CAUTIONARY STATEMENT
WILL REMAIN IN PLACE FOR THE NEARSHORE WATERS N OF SEBASTIAN INLET.
SAT-WED...FLOW WILL VEER TOWARD THE EAST THIS WEEKEND WITH MODERATE
TO FRESH EASTERLY WINDS INTO MONDAY. WINDS EASING A BIT AND BECOMING
MORE VARIABLE TUE/TUE NIGHT AS FRONT MOVES DOWN THE PENINSULA THEN
ONSHORE WINDS RESUME AGAIN RATHER QUICKLY BEHIND THE FRONT. LONG
PERIOD SWELL WILL ELEVATE SEA HEIGHTS BEYOND WHAT WINDS ALONE WOULD
SUGGEST THROUGH THE END OF THE PERIOD.
&&
.FIRE WEATHER...TODAY-TONIGHT...VERY DRY AIRMASS OVERHEAD WITH 00Z
RAOBS MEASURING PWAT VALUES ARND 0.3" ACRS CENTRAL FL. WHILE THE
BULK OF THE DRY AIR IS LOCATED ABV A VERY STRONG SUBSIDENCE
INVERSION IN THE H90-H60 LYR...DEW POINT DEPRESSIONS BLO H90 ARE ON
THE ORDER OF 10C.
EXPECT TO SEE SFC RH FALL BLO 35PCT ARND MIDDAY WEST OF A LINE FROM
LAKE KISSIMMEE TO LAKE MONROE TO LAKE GEORGE...WITH VALUES FALLING
BLO 30PCT ALONG AND N OF THE I-4 CORRIDOR FOR 4-6HRS. LATEST ERC
VALUES OVER EAST CENTRAL FL AND THE SURROUNDING COUNTIES ARE AOB THE
35 THRESHOLD NECESSARY TO TRIGGER AN RFW...WILL GO WITH A FIRE
DANGER STATEMENT INSTEAD AND HIGHLIGHT IN THE HWO.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 71 53 75 60 / 0 0 0 0
MCO 73 53 78 59 / 0 0 0 0
MLB 72 58 76 66 / 0 0 0 0
VRB 73 58 76 66 / 0 0 10 0
LEE 72 51 77 57 / 0 0 0 0
SFB 73 52 78 59 / 0 0 0 0
ORL 74 53 78 60 / 0 0 0 0
FPR 72 57 76 65 / 0 0 10 0
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 7 PM EST
THIS EVENING FOR COASTAL WATERS FROM SEBASTIAN INLET TO
JUPITER INLET OUT 20 NM-WATERS FROM FLAGLER BEACH TO
VOLUSIA BREVARD COUNTY LINE 20 TO 60 NM OFFSHORE-WATERS
FROM SEBASTIAN INLET TO JUPITER INLET 20 TO 60 NM OFFSHORE-
WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET
20 TO 60 NM OFFSHORE.
&&
$$
SHORT TERM/AVIATION...BRAGAW
LONG TERM....GLITTO
AREA FORECAST DISCUSSION
NWS DES MOINES IA
810 PM CST SAT NOV 10 2012
.UPDATE PUBLIC DISCUSSION...
.SHORT TERM /TONIGHT/...
HAVE UPDATED WINDS OVER WESTERN IOWA FOR STRONGER SFC GRADIENT AHEAD
OF FRONT. OTHERWISE...FORECAST LOOKS TO BE ON TARGET WITH THUNDER
TIMING AND COLDER TEMPERATURES BY MORNING.
.PREVIOUS SHORT TERM /TONIGHT/...
ALL ELEMENTS ARE CONCERNS THIS EVENING WITH TREMENDOUS CHANGE IN THE
WEATHER. PARENT LONG WAVE TROUGH OF UPSTREAM SYSTEM IS STILL WEST
OF ROCKIES BUT LEAD CO AND NE SHORT WAVES CONTINUE TO PRODUCE
WIDESPREAD SURFACE PRESSURE FALLS ALONG AND AHEAD OF FRONTAL
BOUNDARY WHICH EXTENDS ACROSS NE INTO SIOUXLAND AREA AT 20Z. NO
ISALLOBARIC MAX OR PUSH EVIDENT AS OF YET SO DO NOT EXPECT MUCH
MOVEMENT FOR AWHILE. WARM SECTOR AIRMASS STILL HAS A WAYS TO GO
BEFORE BECOMING SURFACE BASED WITH 20Z SUBJECTIVE ANALYSIS SHOWING
ONLY 100 J/KG MLCAPES AND CINH ONLY DOWN TO 50 J/KG IN SMALL AREA
ACROSS KS/NE BORDER. LATEST RAP AND NAM SUGGEST ONLY A SMALL WINDOW
FOR THERMODYNAMICS FAVORABLE FOR SURFACE CONVECTION UPSTREAM THROUGH
EARLY EVENING...AND WHAT THERE IS FADES INTO THE NIGHT FARTHER
EAST SO DO NOT REALLY FEEL TORNADOES OR SURFACE BASED STORMS A
THREAT.
HOWEVER LATEST NAM/HRRR AND WRF RUNS ALL SUGGEST SIMILAR
PROGRESSIONS WITH CONVECTION DEVELOPING ACROSS ERN NE ASSOCIATED
WITH FORCING THAT IS CURRENTLY PRODUCING NE/SD SNOW. THIS MOVES
INTO WRN FORECAST AREA AFTER 03Z AND THEN ACROSS REMAINDER OF THE
AREA OVERNIGHT. MODELS ACTUALLY DEPICT FORCING MAX 06-12Z SO PRECIP
MAY ACTUALLY EXPAND EARLY SUN MORNING. WIND WOULD SEEM TO BE OUR
GREATEST SEVERE THREAT WITH STORM MOTION SW-NE 50-60KTS...BUT WITH
WANING INSTABILITY AND SOUNDINGS MOISTENING DO NOT THINK THIS IS A
BIG THREAT OVERALL. TEMPERATURES WILL BE PROBLEMATIC WITH SHARP
GRADIENT ACROSS FRONTAL BOUNDARY. TEMPS SHOULD FALL SHARPLY WITH
FRONT NW...BUT WILL LIKELY NOT REACH FAR SERN SECTIONS UNTIL BEYOND
THIS PERIOD.
.LONG TERM /SUNDAY THROUGH SATURDAY/...
MAIN FORECAST CONCERNS FOR LONG TERM FOCUS AROUND BEGINNING OF
LONG TERM AND PRECIPITATION AND TEMPERATURES FOR SUNDAY AND INTO
SUNDAY NIGHT. STRONG COLD FRONT WILL PUSH ACROSS THE CWA
THROUGHOUT THE DAY SUNDAY...AND ANTICIPATE FROPA NEAR 12Z ACROSS
THE WEST...AND AROUND 15Z FOR CENTRAL LOCATIONS. THIS WILL ALLOW
TEMPERATURES TO DROP THROUGHOUT THE DAY...WITH HIGH TEMPERATURES
OCCURRING BETWEEN VERY NEAR 12Z-15Z OR A LITTLE LATER FURTHER SE.
GOOD MOISTURE ASSOCIATED WITH FRONT AND STRONG FRONTOGENESIS AND
LIFT WILL ALLOW FOR PRECIPITATION WITH FRONT. MOST OF THIS
PRECIPITATION WILL COME AS RAIN WITH WARMER TEMPERATURES AHEAD OF
FRONT. HOWEVER...CLOSER TO THE FRONT AND LINGERING POST-FRONTAL
PRECIPITATION WILL LIKELY BE MIXED.
MIXED PRECIPITATION WILL BE MOST LIKELY ACROSS THE WEST SUNDAY
MORNING BEFORE SWITCHING OVER TO RAIN/SNOW IN THE AFTERNOON. GFS
AND NAM SOUNDINGS DIFFER SLIGHTLY WITH PRECIP TYPE AT
SURFACE...MAINLY DUE TO TIMING DIFFERENCES WITH FROPA.
HOWEVER...FEEL THERE IS A GOOD CHANCE FOR RN/IP NEAR FRONT. WITH
ICE INTRODUCTION ALOFT...FALLING THROUGH STRONG WARM LAYER...NEAR
OR ABOVE 6C...BEFORE STRONG COLD LAYER CLOSER TO SURFACE WITH
FRONT. DEPTH OF NEAR SURFACE COLD LAYER VARIES BY MODEL...BUT MOST
INDICATE A GOOD CHANCE FOR REFREEZING AND COULD SEE SLEET. SURFACE
TEMPERATURES WILL BE SLIGHTLY ABOVE FREEZING...FALLING TO NEAR
FREEZING WITH APPROACHING COLD FRONT. THEREFORE CANNOT RULE OUT
CHANCE FOR LOCALIZED FZRN. HOWEVER...FEEL THIS THREAT IS VERY
MINIMAL WITH WARM SURFACE TEMPERATURES AND SMALL TIMING WINDOW.
HOWEVER...LOCALIZED ICING ON ELEVATED SURFACES IS POSSIBLE EARLY
SUNDAY MORNING ACROSS THE NORTHWEST AND WEST. STRONG FRONT PUSHES
THROUGH QUICKLY PUSHING SOUNDING TEMPS BELOW ZERO THROUGH
COLUMN...ENDING CHANCES FOR MELTING IN WARM LAYER...WITH PRECIP AT
SURFACE CHANGING TO RN/SN MIX. AGAIN...EXPECT LITTLE IN THE WAY OF
ACCUMULATION WITH WARM SURFACE TEMPERATURES AND BULK OF
PRECIPITATION PREFRONTAL AND FALLING AS RAIN.
PRECIPITATION WILL PUSH OUT BY SUNDAY NIGHT...WITH COLD
TEMPERATURES REMAINING. COULD SEE SOME LIGHT FLURRIES ACROSS THE
NORTH MONDAY NIGHT AS LOW TRACKS ACROSS THE NORTH. HOWEVER...NOT A
LOT OF LIFT ASSOCIATED WITH THIS AND HAVE ONLY KEPT FLURRIES
MENTIONED WITH NO ACCUMULATION. FOCUS FOR THE LONG TERM SWITCHES
TO TEMPERATURES THROUGH THE WEEK AS NEARLY ZONAL FLOW SETS UP
ACROSS THE REGION. FEW WAVES WILL PUSH THROUGH THE FLOW...BUT
LITTLE MOISTURE AND HAVE NOT INCLUDED PRECIPITATION CHANCES.
TEMPERATURES WILL STEADILY WARM WITH SOUTHERLY SURFACE FLOW...WITH
HIGHS IN THE 40S AND 50S FOR THE END OF THE WEEK. MODELS CONTINUE
TO DEVELOP ANOTHER AREA OF LOW PRESSURE EAST OF THE ROCKIES FOR
LATE IN THE WEEK. HOWEVER...HAVE SIGNIFICANTLY SLOWED DOWN THIS
DEVELOPMENT AND HAVE THEREFORE CUT BACK ON PRECIPITATION CHANCES
FOR FRIDAY WITH ONLY CHANCES MENTIONED SATURDAY. MAY SEE A
CONTINUED SLOWING TREND WITH THIS SYSTEM AND WILL LIKELY SEE BEST
CHANCES FOR PRECIPITATION RETURNING AGAIN AFTER THE END OF THE
PERIOD.
&&
.AVIATION...11/00Z
MAIN SHORTWAVE STILL TO WEST WITH MAIN LINE OF THUNDER EXPECTED TO
ARRIVE 06-12Z. SCATTERED ACTIVITY WILL MOVE ACROSS SOUTHERN IOWA
THIS EVENING WITH STRONG SOUTH WINDS CONTINUING. AS THE FRONT
CROSSES THE STATE FROM 06Z WEST TO 13Z EAST WINDS WILL SWING AROUND
TO NW DIRECTION AND INCREASE DURING THE MORNING HOURS. AS COLD AIR
MIXES INTO THE BACK SIDE OF THE SYSTEM RAIN MIXES IN WITH SNOW AND
THEN CHANGES OVER TO SNOW AS THE SYSTEM DEPARTS. WINDS WILL
GRADUALLY DIMINISH TOWARD 00Z AS SFC GRADIENT WEAKENS. CIGS WILL
REMAIN RATHER LOW FOR MUCH OF THE DAY BUT LIFT TOWARD 20-00Z
TIMEFRAME.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...SMALL/REV
LONG TERM...AWB
AVIATION...REV
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
535 PM CST SAT NOV 10 2012
...UPDATED FOR THE 00Z AVIATION TAF DISCUSSION...
.SYNOPSIS...
ISSUED AT 336 PM CST SAT NOV 10 2012
AN INTENSE STORM SYSTEM WAS MATURING OVER THE ROCKIES AND ADJACENT
GREAT PLAINS TODAY. AFTERNOON RAP ANALYSIS SHOWED A 400MB JET STREAK
OF 100+ KNOTS EXTENDING CYCLONICALLY FROM NORTHEASTERN NEW MEXICO
THROUGH CENTRAL ARIZONA INTO CENTRAL CALIFORNIA. THIS SIGNIFICANT
CYCLONICALLY CURVED JET HAS HELPED SPAWN A DEEP SURFACE LOW AROUND
993MB OVER EASTERN COLORADO THIS AFTERNOON. LOWER-MID TROPOSPHERIC
WIND SPEEDS FROM THE SOUTHWEST WERE 50 TO 70 KNOTS, WHICH WAS THE
TOP OF THE MIXED LAYER IN MANY PLACES ACROSS THE HIGH PLAINS. THIS
LED TO WIDESPREAD SURFACE HIGH WIND EVENT WITH NUMEROUS OBS GUSTING
50 TO EVEN 60 KNOTS AT TIMES. MOST IMPRESSIVELY WAS A RECENT
OBSERVATION AT TUCUMCARI NEW MEXICO OF A 64 KNOT GUST. WIDESPREAD
BLOWING DUST WAS ALSO OCCURRING WITHIN THE HIGH WIND AREA,
EXACERBATED BY THE LONG TERM DROUGHT CONDITIONS. A SHALLOW, NEARLY
STATIONARY SURFACE FRONT THIS MORNING LIFTED BACK NORTH FROM
NORTHWEST KANSAS INTO CENTRAL NEBRASKA AS A WARM FRONT WITH THE
SURFACE LOW STRENGTHENING. THIS QUASI-STATIONARY FRONT AT 19Z
EXTENDED FROM THE 993MB SURFACE LOW NORTHEAST OF LA JUNTA, COLORADO
TO NEAR GOODLAND, KS TO COLUMBUS, NE. THE SURFACE BAROCLINIC ZONE
WAS VERY IMPRESSIVE WITH A TEMPERATURE OF 17F AT CASPER, WYOMING
NORTH OF THE FRONT IN THE ARCTIC AIRMASS AND 79F AT HAYS, KANSAS.
&&
.SHORT TERM...(THIS EVENING AND OVERNIGHT)
ISSUED AT 336 PM CST SAT NOV 10 2012
THE HIGH WIND EVENT WILL CONTINUE WEST OF THE DRYLINE THROUGH 23Z OR
SO, AT WHICH POINT WINDS WILL SLOWLY SLACKEN OFF WITH DUST SETTLING.
AS FAR AS THE PRECIPITATION CHANCES GO, NO CHANGE IN THE CURRENT
FORECAST IS EXPECTED. DEWPOINT TEMPERATURES HAVE NOT BEEN ANY HIGHER
THAN THE MID 50S, WHICH RESULTED IN CAPE 800-1000 J/KG. DESPITE THE
VERY IMPRESSIVE LOW LEVEL AND DEEP LAYER SHEAR, THE LACK OF
APPRECIABLE INSTABILITY AND LOW LEVEL MOISTURE SHOULD PRECLUDE
WIDESPREAD SEVERE WEATHER. THAT BEING SAID, INTENSE MID LEVEL COLD
ADVECTION WILL BE INCREASING, ALLOWING CAPE PROFILES TO IMPROVE THIS
EVENING. WINDOW FOR SEVERE WEATHER SHOULD BE DURING THE 00-04Z TIME
FRAME, WITH THE LINE OF FORCING AND PACIFIC COLD FRONT MOVING
THROUGH SOUTHWEST KANSAS/WESTERN PORTIONS OF SOUTH CENTRAL KANSAS.
THE CANADIAN COLD FRONT WILL BE MOVING THROUGH DURING THE 09-12Z
TIME FRAME ACROSS SOUTHWEST KANSAS, AT WHICH POINT WE WILL SEE
STRONG COLD AIR ADVECTION WITH -8 TO -11C 850MB TEMPERATURES DRIVING
SOUTH. THERE WILL BE SLIGHT DOWNSLOPE MODIFICATION OF THIS AIRMASS
AS WESTERLY COMPONENT MOMENTUM INCREASES OFF THE ROCKIES OF COLORADO
AND WYOMING. WITH THE ADVECTION OF THE MODIFIED ARCTIC AIRMASS, LOW
STRATUS MAY BE A CONCERN AND WILL BUMP UP THE SKY GRIDS A LITTLE BIT
TO ACCOUNT FOR A LITTLE MORE CLOUD THAN EARLIER THOUGHT WITH THE
INITIAL ONSET OF THE COLD AIR AROUND 09Z OR SO.
.LONG TERM...(SUNDAY THROUGH SATURDAY)
ISSUED AT 336 PM CST SAT NOV 10 2012
COLD AIR WILL INVADE WESTERN KANSAS BEHIND THE FRONT BY EARLY SUNDAY
MORNING. HOWEVER, SOME DOWNSLOPE MODIFICATION ON THE WESTERN EDGE OF THE
COLD AIRMASS WILL ALLOW TEMPERATURES TO RISE INTO THE LOWER TO MID
40S IN MOST LOCATIONS. THE COLDEST NIGHT SO FAR THIS FALL IS EXPECTED
BY SUNDAY NIGHT AS WINDS DECREASE AND CLOUD COVER THINS. LOWS SHOULD
BE IN THE UPPER TEENS TO LOWER 20S BY MONDAY MORNING.
FAIRLY CHILLY AIR WILL PERSIST ON MONDAY AS THE COLD SURFACE HIGH
PRESSURE WILL STILL BE JUST OFF TO THE SOUTHEAST, WITH SEA LEVEL
PRESSURES STILL AROUND 1030MB OVER WESTERN KANSAS. HIGHS SHOULD
ONLY REACH INTO THE UPPER 40S TO LOWER 50S. ANOTHER COLD NIGHT
CAN BE EXPECTED MONDAY NIGHT AS SURFACE HIGH PRESSURE LINGERS TO OUR
EAST. LOWS OUGHT TO BE IN THE 20S.
MAINLY ZONAL MID TO HIGH LEVEL FLOW CAN BE EXPECTED TUESDAY THROUGH
SATURDAY. WEAK LEE TROUGHING WILL DEVELOP IN RESPONSE TO THE
MID-LEVEL DOWNSLOPE FLOW ON TUESDAY AND PERSIST INTO THURSDAY. THIS
WILL LEAD TO SOUTHERLY LOW LEVEL WINDS AND WARMER HIGHS IN THE UPPER
50S AND LOWER 60S. SOME BOUNDARY LAYER DECOUPLING CAN BE EXPECTED
EACH NIGHT GIVEN THE RATHER WEAK PRESSURE GRADIENT. AND GIVEN THE
RELATIVELY DRY AIR AT LOWER LEVELS, TEMPERATURES SHOULD HAVE NO
PROBLEM FALLING INTO THE 30S EACH NIGHT THROUGH FRIDAY. SOME 20S
CANNOT BE RULED OUT IN LOW-LYING AREAS.
A SHORTWAVE TROUGH IS ADVERTISED BY THE VARIOUS MODELS TO APPROACH
THE PLAINS BY LATE FRIDAY INTO SATURDAY. GIVEN THE PROGRESSIVENESS
OF THIS SYSTEM, PRECIPITATION IS NOT LIKELY AS LOW-LEVEL MOISTURE
WILL NOT MAKE IT THIS FAR WEST. HOWEVER, SINCE THE MODELS DO SHOW
SOME MID-LEVEL MOISTURE, ISENTROPIC LIFT AND SMALL AMOUNTS OF QPF,
VERY SMALL CHANCES FOR RAIN WERE MAINTAINED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 524 PM CST SAT NOV 10 2012
AS A COLD FRONT MOVES EAST AND OVERTAKES A DRY LINE ACROSS CENTRAL
KANSAS THIS EVENING, THE ASSOCIATED CONVECTIVE ACTIVITY WILL ALSO
MOVE EAST OF THE TAF SITES. STRONG SOUTHWEST WINDS SHOULD SETTLE
DOWN TO AROUND NORTHWEST AT 15 KNOTS AFTER SUNDOWN. THEN THE LOWER
030-045 STRATUS CLOUDS WILL ALSO CLEAR OUT AND LEAVE MID LEVEL
BROKEN CLOUDS. NORTH WINDS WILL PICK UP TOWARD MORNING, AND BLOW
IN THE 15G30KT RANGE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 31 44 21 52 / 10 0 0 0
GCK 28 43 19 52 / 10 0 0 0
EHA 28 44 21 51 / 10 10 10 0
LBL 30 44 20 52 / 10 10 10 0
HYS 30 42 19 51 / 10 0 0 0
P28 40 46 23 52 / 40 0 10 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 7 PM CST THIS EVENING FOR KSZ030-031-045-046-
064>066-077>081-087>090.
HIGH WIND WARNING UNTIL 7 PM CST /6 PM MST/ THIS EVENING FOR
KSZ043-044-061>063-074>076-084>086.
RED FLAG WARNING UNTIL 7 PM CST /6 PM MST/ THIS EVENING FOR
KSZ043-044-061>063-074>076-084>086.
&&
$$
SYNOPSIS...UMSCHEID
SHORT TERM...UMSCHEID
LONG TERM...FINCH
AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS GOODLAND KS
251 PM MST FRI NOV 9 2012
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 224 PM MST FRI NOV 9 2012
LATEST WV IMAGERY AND RUC H5 ANALYSIS SHOW BROAD RIDGE ACROSS THE
EASTERN US CENTERED OVER THE OHIO RIVER VALLEY. UPSTREAM A TROUGH
EXTENDS SOUTH ACROSS THE WESTERN US WITH A CLOSED CENTER OVER
WASHINGTON STATE. SW FLOW IS IN PLACE OVER THE CWA BETWEEN THESE
FEATURES. AT THE SURFACE A STATIONARY FRONT CURRENTLY EXTENDS
ACROSS EASTERN COLORADO TO SOUTHWEST KANSAS.
A WARM FRONT WILL LIFT ACROSS THE CWA TONIGHT WITH BREEZY SW WINDS
AND WARMER H85 TEMPS RESULTING IN OVERNIGHT LOWS IN 40S FOR MOST
LOCATIONS. THE TROUGH OVER THE WESTERN US WILL BEGIN TO SHIFT EAST
ACROSS THE INTER-MOUNTAIN WEST THROUGH SUNDAY WITH AN ASSOCIATED
COLD FRONT MOVING SOUTHEAST TOWARDS THE CWA SATURDAY AFTERNOON.
AHEAD OF THIS FRONT SURFACE PRESSURE GRADIENT WILL BE INCREASING
FROM THE S-SW WITH H85 JET BETWEEN 40-45KT. CONFIDENCE IS HIGHEST
THAT WIND ADVISORY CRITERIA WILL BE MET ACROSS THE SOUTHEAST
CWA...THOUGH IF H7 WINDS WERE ABLE TO MIX DOWN WE COULD APPROACH
WARNING CRITERIA. IM NOT SURE WE WILL SEE 3HR OF SUSTAINED
CRITERIA IN SHERMAN COUNTY AND CHEYENNE/KIT CARSON COLORADO
COUNTIES. HOWEVER...WE SHOULD SEE GUSTS AROUND 45 MPH THERE SO I
WAS COMFORTABLE INCLUDING THEM IN THE ADVISORY.
AHEAD OF THE COLD FRONT A DRY LINE WILL SET UP ACROSS CENTRAL
KANSAS WITH THUNDERSTORMS DEVELOPING AHEAD OF THIS FEATURE. ALL
CURRENT GUIDANCE IS SHOWING THE DRY LINE REMAINING EAST OF THE
CWA...SO I DELAYED ONSET OF PRECIP IN THE EAST UNTIL FROPA AND
LEFT THUNDER OUT OF FORECAST. BEST CHANCE FOR PRECIP SHOULD BE
ACROSS THE NORTHWEST ALONG AND BEHIND THE COLD FRONT WHERE BEST
LARGE SCALE ASCENT AND GOOD MOISTURE ADVECTION WILL SPREAD INTO
CWA BY 00Z.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 240 PM MST FRI NOV 9 2012
THE COLD FRONT WILL BLAST THROUGH THE AREA SATURDAY EVENING AND
NIGHT. MODELS CONTINUE TO SHOW PRECIPITATION DEVELOPING BEHIND THE
FRONT. AS THE PRECIPITATION AND COLD AIR CONTINUE TO MOVE IN...A
CHANGE FROM RAIN TO SNOW IS EXPECTED. MOST MODELS...THE
CANADIAN...THE EUROPEAN AND THE NAM TO BE SPECIFIC...HAVE INCREASED QPF
AMOUNTS FROM PREVIOUS RUNS WHILE THE GFS HAS DECREASED QPF
AMOUNTS. THEREFORE...SLIGHTLY HIGHER PRECIPITATION AMOUNTS ARE NOW
FORECAST. THIS LEADS TO SNOWFALL AMOUNTS RANGING FROM A TRACE IN
MOST AREAS TO AS HIGH AS AN INCH IN YUMA COUNTY COLORADO. HPC IS
SUGGESTING TOTALS COULD BE AS HIGH AS 2 INCHES IN NORTHERN YUMA
COUNTY AND WOULD NOT BE SURPRISED IF THIS HAPPENED.
A COLD SURFACE HIGH PRESSURE SYSTEM WILL BUILD IN ON SUNDAY. THIS
WILL KEEP TEMPERATURES QUITE CHILLY WITH HIGHS IN THE 30S. BREEZY
NORTH WINDS WILL CONTINUE ON SUNDAY BEHIND THE COLD FRONT. A FEW
ADDITIONAL SNOW SHOWERS ARE POSSIBLE IN EASTERN COLORADO ON SUNDAY
MORNING...WITH ALL THE PRECIPITATION CLEARING OUT BY SUNDAY
AFTERNOON.
THE COLDEST NIGHT OF THE FALL IS EXPECTED ON SUNDAY NIGHT. THE COLD
SURFACE HIGH PRESSURE WILL SETTLE IN FOR THE NIGHT. IN
ADDITION...THE WINDS WILL WEAKEN AND SKIES WILL CLEAR. THIS WILL
ALLOW FOR TEMPERATURES TO DROP INTO THE TEENS SUNDAY NIGHT. EVEN
WITH LIGHT WINDS...WIND CHILLS ARE CURRENTLY FORECAST TO FALL INTO
THE SINGLE DIGITS BY MONDAY MORNING.
A WEAK UPPER LEVEL RIDGE OF HIGH PRESSURE WILL BUILD INTO THE
TRI-STATE AREA ON MONDAY. THIS WILL BLOCK ANY WEATHER SYSTEMS
FROM MOVING IN UNTIL THE END OF THE WEEK. THEREFORE...NO RAIN IS
EXPECTED THROUGH AT LEAST WEDNESDAY. TEMPERATURES WILL BE BELOW
NORMAL FOR MONDAY. HOWEVER...A WARMING TREND IS EXPECTED FOR THE
MIDDLE OF THE WEEK AS WINDS RETURN FROM THE SOUTH.
MODEL AGREEMENT FROM YESTERDAY ON THE NEXT WEATHER SYSTEM HAS TURNED
INTO COMPLETE MODEL DISAGREEMENT. THE CANADIAN MODEL SHOWS AN
UPPER LEVEL TROUGH MOVING INTO THE REGION WITH A LEE TROUGH DEVELOPING
ON THURSDAY MORNING. THE CANADIAN MODEL SHOWS A LARGE AREA OF
PRECIPITATION JUST TO THE NORTH OF THE LEE TROUGH OVER
NEBRASKA...WYOMING AND SOUTH DAKOTA. THE EUROPEAN MODEL IS FAIRLY
CONSISTENT WITH YESTERDAYS 12Z MODEL RUN WITH A LONGWAVE TROUGH
MOVING INTO THE AREA THURSDAY NIGHT INTO FRIDAY. THE EUROPEAN
MODEL HAS PRECIPITATION DEVELOPING AHEAD OF THE TROUGH OVER THE
TRI-STATE THURSDAY NIGHT THROUGH FRIDAY. THE GFS MODEL IS NOW
FORECASTING A VERY WEAK TROUGH MOVING THROUGH LATER...NOW ON
SATURDAY INSTEAD OF FRIDAY. THE GFS MODEL AMPLIFIES THIS TROUGH TO
THE EAST AND DEVELOPS PRECIPITATION AHEAD OF IT...THUS MISSING THE
TRI-STATE AREA. IT IS HARD TO DECIDE WHICH MODEL IS CORRECT AT THE
MOMENT...SO JUST WENT WITH THE MODEL BLEND. THIS SUGGESTED SLIGHT
CHANCE AND LOW END CHANCE POPS FOR THURSDAY NIGHT THROUGH FRIDAY.
AT THE PRESENT TIME...MODELS ARE NOT SHOWING ANOTHER STRONG COLD
FRONT MOVING IN BEHIND THE NEXT WEATHER SYSTEM SO HAVE GONE WITH A
PERSISTENCE FORECAST OF NEAR NORMAL TEMPERATURES FOR THE END OF
THE WORK WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1050 AM MST FRI NOV 9 2012
VFR CONDITIONS ARE EXPECTED TO PREVAIL THRU THE TAF PERIOD AT BOTH
MCK AND GLD...WITH A CHANCE OF MVFR LATE IN THE PERIOD AT MCK. FOR
THE REST OF TODAY THERE WILL BE A FEW HIGH CLOUDS AS SURFACE WINDS
TURN FROM THE EAST TO SOUTH. WIND SPEEDS WILL BE LIGHT
TODAY...INCREASING AT GLD EARLY TOMORROW MORNING AT GLD AS A SURFACE
TROUGH OVER EASTERN COLORADO STRENGTHENS AND A WARM FRONT GRADUALLY
PUSHES NORTH THROUGH THE AREA. AT MCK THERE IS THE POSSIBILITY FOR
MVFR VISIBILITIES EARLY MONDAY MORNING SIMILAR TO TODAY...WITH MOST
SHORT RANGE GUIDANCE SUPPORTING THIS IDEA. HOWEVER...DID NOT INCLUDE
MENTION IN TAF DUE TO LACK OF CONFIDENCE OF HOW FAR NORTH THE FRONT
MOVES OVERNIGHT WHICH WILL DETERMINE WHERE FOG DEVELOPS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WIND ADVISORY FROM 11 AM MST /NOON CST/ TO 5 PM MST /6 PM CST/
SATURDAY FOR KSZ003-004-013>016-027>029-041-042.
CO...WIND ADVISORY FROM 11 AM TO 5 PM MST SATURDAY FOR COZ091-092.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...RRH
AVIATION...JJM/DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
224 PM MST FRI NOV 9 2012
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 224 PM MST FRI NOV 9 2012
LATEST WV IMAGERY AND RUC H5 ANALYSIS SHOW BROAD RIDGE ACROSS THE
EASTERN US CENTERED OVER THE OHIO RIVER VALLEY. UPSTREAM A TROUGH
EXTENDS SOUTH ACROSS THE WESTERN US WITH A CLOSED CENTER OVER
WASHINGTON STATE. SW FLOW IS IN PLACE OVER THE CWA BETWEEN THESE
FEATURES. AT THE SURFACE A STATIONARY FRONT CURRENTLY EXTENDS
ACROSS EASTERN COLORADO TO SOUTHWEST KANSAS.
A WARM FRONT WILL LIFT ACROSS THE CWA TONIGHT WITH BREEZY SW WINDS
AND WARMER H85 TEMPS RESULTING IN OVERNIGHT LOWS IN 40S FOR MOST
LOCATIONS. THE TROUGH OVER THE WESTERN US WILL BEGIN TO SHIFT EAST
ACROSS THE INTER-MOUNTAIN WEST THROUGH SUNDAY WITH AN ASSOCIATED
COLD FRONT MOVING SOUTHEAST TOWARDS THE CWA SATURDAY AFTERNOON.
AHEAD OF THIS FRONT SURFACE PRESSURE GRADIENT WILL BE INCREASING
FROM THE S-SW WITH H85 JET BETWEEN 40-45KT. CONFIDENCE IS HIGHEST
THAT WIND ADVISORY CRITERIA WILL BE MET ACROSS THE SOUTHEAST
CWA...THOUGH IF H7 WINDS WERE ABLE TO MIX DOWN WE COULD APPROACH
WARNING CRITERIA. IM NOT SURE WE WILL SEE 3HR OF SUSTAINED
CRITERIA IN SHERMAN COUNTY AND CHEYENNE/KIT CARSON COLORADO
COUNTIES. HOWEVER...WE SHOULD SEE GUSTS AROUND 45 MPH THERE SO I
WAS COMFORTABLE INCLUDING THEM IN THE ADVISORY.
AHEAD OF THE COLD FRONT A DRY LINE WILL SET UP ACROSS CENTRAL
KANSAS WITH THUNDERSTORMS DEVELOPING AHEAD OF THIS FEATURE. ALL
CURRENT GUIDANCE IS SHOWING THE DRY LINE REMAINING EAST OF THE
CWA...SO I DELAYED ONSET OF PRECIP IN THE EAST UNTIL FROPA AND
LEFT THUNDER OUT OF FORECAST. BEST CHANCE FOR PRECIP SHOULD BE
ACROSS THE NORTHWEST ALONG AND BEHIND THE COLD FRONT WHERE BEST
LARGE SCALE ASCENT AND GOOD MOISTURE ADVECTION WILL SPREAD INTO
CWA BY 00Z.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 1148 PM MST THU NOV 8 2012
LOW AMPLITUDE SHORTWAVE RIDGE WILL CROSS THE PLAINS DURING THE
PERIOD MONDAY THROUGH WEDNESDAY. DRY CONDITIONS AND BELOW NORMAL
TEMPERATURES ARE EXPECTED. NEXT SYSTEM WILL BE ORGANIZING IN THE
DESERT SOUTHWEST AND MAKES ITS WAY INTO THE SOUTHERN AND CENTRAL
PLAINS LATE IN THE WEEK. THERE ARE STILL SIGNIFICANT MODEL
DIFFERENCES WITH TIMING AND STRENGTH OF THE SYSTEM...BUT APPEARS
IT WILL BRING A DECENT CHANCE OF PRECIPITATION. COLD AIR WILL BE
LACKING...SO THINK IT WILL BE MAINLY RAIN WITH PERHAPS SOME LIGHT
SNOW ON THE BACKSIDE AS IT DEPARTS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1050 AM MST FRI NOV 9 2012
VFR CONDITIONS ARE EXPECTED TO PREVAIL THRU THE TAF PERIOD AT BOTH
MCK AND GLD...WITH A CHANCE OF MVFR LATE IN THE PERIOD AT MCK. FOR
THE REST OF TODAY THERE WILL BE A FEW HIGH CLOUDS AS SURFACE WINDS
TURN FROM THE EAST TO SOUTH. WIND SPEEDS WILL BE LIGHT
TODAY...INCREASING AT GLD EARLY TOMORROW MORNING AT GLD AS A SURFACE
TROUGH OVER EASTERN COLORADO STRENGTHENS AND A WARM FRONT GRADUALLY
PUSHES NORTH THROUGH THE AREA. AT MCK THERE IS THE POSSIBILITY FOR
MVFR VISIBILITIES EARLY MONDAY MORNING SIMILAR TO TODAY...WITH MOST
SHORT RANGE GUIDANCE SUPPORTING THIS IDEA. HOWEVER...DID NOT INCLUDE
MENTION IN TAF DUE TO LACK OF CONFIDENCE OF HOW FAR NORTH THE FRONT
MOVES OVERNIGHT WHICH WILL DETERMINE WHERE FOG DEVELOPS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WIND ADVISORY FROM 11 AM MST /NOON CST/ TO 5 PM MST /6 PM CST/
SATURDAY FOR KSZ003-004-013>016-027>029-041-042.
CO...WIND ADVISORY FROM 11 AM TO 5 PM MST SATURDAY FOR COZ091-092.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...024
AVIATION...JJM/DR
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
945 PM EST SAT NOV 10 2012
.SYNOPSIS...
ISSUED AT 345 PM EST SAT NOV 10 2012
UNSEASONABLY WARM CONDITIONS CAN BE EXPECTED TONIGHT AND SUNDAY AS A
WARM FRONT LIFTS NORTH OF THE STATE. WINDY CONDITIONS WITH GUSTS TO
40 MPH WILL DEVELOP ON SUNDAY AFTERNOON AS TEMPERATURES RISE INTO
THE 60S TO NEAR 70.
WIDESPREAD RAIN WILL IMPACT THE REGION SUNDAY NIGHT INTO EARLY
MONDAY AS A COLD FRONT MOVES SLOWLY EAST. MUCH COLDER AIR AND
SCATTERED SNOW SHOWERS WILL FOLLOW BEHIND THE FRONT MONDAY AFTERNOON
AND NIGHT. NO SNOW ACCUMULATIONS ARE EXPECTED. OTHERWISE MOST OF
NEXT WEEK LOOKS DRY WITH MODERATING TEMPERATURES.
&&
.UPDATE...
ISSUED AT 944 PM EST SAT NOV 10 2012
TWEAKED POP GRIDS TO REFLECT ISOLATED SHOWERS MOVING ACROSS THE
AREA. SFC ANALYSIS SHOWS THE WARM FRONT STRETCHING FROM NEAR
LUDINGTON TO ALMA. AS THE FRONT MOVES NORTH...CHANCES FOR PCPN
WILL SLOWLY DECREASE OVERNIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 345 PM EST SAT NOV 10 2012
AREA OF CONVECTION WHICH EARLIER PRODUCED NUMEROUS REPORTS OF HAIL
OVER NRN IL IS WEAKENING CONSIDERABLY AS IT HEADS INTO FAR SOUTHERN LWR
MI. SCATTERED SHOWERS WILL IMPACT THE I-94 CORRIDOR THROUGH 00Z.
THERE IS ANOTHER BATCH OF SCATTERED RAIN SHOWERS MOVING NE FROM
IA/MO AND FOR THAT REASON WILL STILL MAINTAIN A SMALL POP THIS
EVENING BEFORE GOING COMPLETELY DRY LATER TONIGHT.
MAIN CONCERN FOR SUNDAY IS WHETHER OR NOT A WIND ADVISORY WILL BE
NEEDED. THAT WILL DEPEND ON HOW WARM IT GETS AND HOW DEEPLY MIXED
THE ATMOSPHERE BECOMES. IT/S PRETTY TOUGH TO MIX DEEPLY IN
NOVEMBER... BUT BUFKIT MIXED LAYER PROGS SUGGEST SOME GUSTS TO 40
KTS ARE POSSIBLE IN THE AFTERNOON. FOR NOW WILL GO WITH GUSTS JUST
SHORT OF ADVISORY CRITERIA.
NO CHANGE TO LATER PERIODS. CATEGORICAL POPS FOR RAIN AS THE COLD
FRONT COMES THROUGH SUNDAY NIGHT/EARLY MONDAY... DIMINISHING TO
CHANCE POPS FOR SNOW OR MIXED RAIN/SNOW SHOWERS BY MONDAY AFTERNOON.
WHILE THE COLD ADVECTION BEHIND THE FRONT IS IMPRESSIVE... MOISTURE
BAILS OUT QUICKLY. THEREFORE NO SNOW ACCUMULATIONS ANTICIPATED ATTM
MONDAY AFTERNOON AND NIGHT.
.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 345 PM EST SAT NOV 10 2012
EVEN THOUGH WE SHOULD BE IN THE HEART OF THE COLD AIR EARLY
TUESDAY...WITH H8 TEMPS AROUND -7C...ANY LAKE EFFECT SNOW SHOWERS
SHOULD BE ENDED WITH ANTICYCLONIC FLOW DEVELOPING EARLY.
OVERALL THE EXTENDED PERIOD LOOKS RATHER UNEVENTFUL. A BLOCKING
RIDGE OFF THE EAST COAST WILL STALL SURFACE HIGH PRESSURE OVER NEW
ENGLAND BY MID TO LATE IN THE WEEK. A LOBE OF HIGH PRESSURE IS
EXPECTED TO LINGER OVER THE LOWER GREAT LAKES AS THIS OCCURS KEEPING
FAIR WEATHER FOR THE BULK OF THE REGION.
THERE SHOULD BE A COUPLE OF WEAK SHORT WAVES THAT TRY TO RUN INTO
THIS BLOCKING RIDGE. THE FIRST PASSES MI LATE THURSDAY OR THURSDAY
NIGHT...WITH THE SECOND ARRIVING SATURDAY. BOTH FEATURES COULD PASS
THROUGH DRY HOWEVER.
WE SHOULD SEE A SLOW MODERATION IN TEMPS THROUGH THE PERIOD WITH
UPPER 30S TO AROUND 40 FOR HIGHS ON TUESDAY...WARMING TO AROUND 50
BY SATURDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 633 PM EST SAT NOV 10 2012
THERE AT THREE IMPORTANT ISSUES TONIGHT. FIRST IS THE POTENTIAL
FOR THUNDERSTORMS WITH HAIL THIS EVENING. THE NEST ISSUE IS THE
LOW LEVEL WIND SHEAR.... WINDS NEAR 2000 FT ALG SHOULD BE ABOUT
200 DEGREES AROUND 50 KNOTS MOST OF THE NIGHT. WITH WINDS ON THE
GROUND OF 190 DEGREES AT 15 KNOTS... THAT WOULD MORE THAN CREATE
SIGNIFICANT LOW LEVEL WIND SHEAR. FINALLY THERE IS THE VERY STRONG
WINDS NEAR THE SURFACE SUNDAY. I COULD SEE SOUTH WINDS OF 25 KNOTS
GUSTING TO 35 KNOTS DURING THE LATE MORNING AND AFTERNOON.
AN AREA OF SHOWERS OVER CENTRAL LAKE MICHIGAN BACK TO SOUTHERN
WISCONSIN IS LIFTING NORTH WITH THE WARM FRONT THIS EVENING. THERE
IS CONSIDERABLE MID LEVEL INSTABILITY... IN FACT RAP SOUNDINGS FOR
MKG/GRR SHOW UP TO 700 J/KG OF ELEVATED CAPE TILL 04Z OR SO WITH
AN EQUILIBRIUM LEVEL NEAR 35000... AND THE GREATEST CAPE IS NEAR
THE -15C ISOTHERM. THIS TELLS ME HAIL IS POSSIBLE IF THESE STORMS
IN FACT DEVELOP. SO I PUT VCTS IN THE I-96 TAF GROUP TILL 04Z TO
ALLOW FOR THE WARM FRONT CONVECTION TO PASS THOUGHT THE AREA.
BEYOND THAT I ALREADY MENTIONED THE LOW LEVEL WIND SHEAR AND I
HAVE THAT IN THE TAFS UNTIL THE SUN MIXES THE BOUNDARY LAYER
AROUND 15Z. ONCE THAT HAPPENS EXPECT THOSE STRONG WINDS TO BE
CLOSER TO THE GROUND SO 20 TO 30 KNOT WINDS NEAR THE GROUND SHOULD
BE EXPECTED AT ALL TAF SITES.
THE CONVECTION WITH THE COLD FRONT SHOULD HOLD OFF UNTIL AFTER 00Z
SO NOT MUCH AN ISSUE WITH THIS SET OF TAFS.
&&
.MARINE...
ISSUED AT 345 PM EST SAT NOV 10 2012
SOUTH FLOW WILL BE INCREASING TONIGHT AND SUNDAY... WITH GUSTS TO
GALES FORCE NOW LOOKING MORE LIKELY SUNDAY. WILL CONTINUE THE SMALL
CRAFT ADVISORY TONIGHT BUT HAVE UPGRADED TO A GALE WARNING FOR
SUNDAY INTO SUNDAY EVENING WHEN THE CORE OF STRONGEST WINDS IS
IMPACTING THE NEARSHORE.
&&
.HYDROLOGY...
ISSUED AT 345 PM EST SAT NOV 10 2012
WIDESPREAD RAIN AMOUNTS OF 0.50 TO 0.75 WITH THE COLD FRONT SUNDAY
NIGHT INTO EARLY MONDAY WILL BRING ONLY SLIGHT RISES ON RIVERS WHICH
HAVE BEEN RUNNING WAY BELOW ACTION STAGE. THUS NO HYDRO ISSUES
ANTICIPATED.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 10 AM EST SUNDAY FOR LMZ844>849.
GALE WARNING FROM 10 AM TO 10 PM EST SUNDAY FOR LMZ844>849.
&&
$$
UPDATE...93
SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...JK
AVIATION...WDM
HYDROLOGY...MEADE
MARINE...MEADE
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
634 PM EST SAT NOV 10 2012
.SYNOPSIS...
ISSUED AT 345 PM EST SAT NOV 10 2012
UNSEASONABLY WARM CONDITIONS CAN BE EXPECTED TONIGHT AND SUNDAY AS A
WARM FRONT LIFTS NORTH OF THE STATE. WINDY CONDITIONS WITH GUSTS TO
40 MPH WILL DEVELOP ON SUNDAY AFTERNOON AS TEMPERATURES RISE INTO
THE 60S TO NEAR 70.
WIDESPREAD RAIN WILL IMPACT THE REGION SUNDAY NIGHT INTO EARLY
MONDAY AS A COLD FRONT MOVES SLOWLY EAST. MUCH COLDER AIR AND
SCATTERED SNOW SHOWERS WILL FOLLOW BEHIND THE FRONT MONDAY AFTERNOON
AND NIGHT. NO SNOW ACCUMULATIONS ARE EXPECTED. OTHERWISE MOST OF
NEXT WEEK LOOKS DRY WITH MODERATING TEMPERATURES.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 345 PM EST SAT NOV 10 2012
AREA OF CONVECTION WHICH EARLIER PRODUCED NUMEROUS REPORTS OF HAIL
OVER NRN IL IS WEAKENING CONSIDERABLY AS IT HEADS INTO FAR SOUTHERN LWR
MI. SCATTERED SHOWERS WILL IMPACT THE I-94 CORRIDOR THROUGH 00Z.
THERE IS ANOTHER BATCH OF SCATTERED RAIN SHOWERS MOVING NE FROM
IA/MO AND FOR THAT REASON WILL STILL MAINTAIN A SMALL POP THIS
EVENING BEFORE GOING COMPLETELY DRY LATER TONIGHT.
MAIN CONCERN FOR SUNDAY IS WHETHER OR NOT A WIND ADVISORY WILL BE
NEEDED. THAT WILL DEPEND ON HOW WARM IT GETS AND HOW DEEPLY MIXED
THE ATMOSPHERE BECOMES. IT/S PRETTY TOUGH TO MIX DEEPLY IN
NOVEMBER... BUT BUFKIT MIXED LAYER PROGS SUGGEST SOME GUSTS TO 40
KTS ARE POSSIBLE IN THE AFTERNOON. FOR NOW WILL GO WITH GUSTS JUST
SHORT OF ADVISORY CRITERIA.
NO CHANGE TO LATER PERIODS. CATEGORICAL POPS FOR RAIN AS THE COLD
FRONT COMES THROUGH SUNDAY NIGHT/EARLY MONDAY... DIMINISHING TO
CHANCE POPS FOR SNOW OR MIXED RAIN/SNOW SHOWERS BY MONDAY AFTERNOON.
WHILE THE COLD ADVECTION BEHIND THE FRONT IS IMPRESSIVE... MOISTURE
BAILS OUT QUICKLY. THEREFORE NO SNOW ACCUMULATIONS ANTICIPATED ATTM
MONDAY AFTERNOON AND NIGHT.
.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 345 PM EST SAT NOV 10 2012
EVEN THOUGH WE SHOULD BE IN THE HEART OF THE COLD AIR EARLY
TUESDAY...WITH H8 TEMPS AROUND -7C...ANY LAKE EFFECT SNOW SHOWERS
SHOULD BE ENDED WITH ANTICYCLONIC FLOW DEVELOPING EARLY.
OVERALL THE EXTENDED PERIOD LOOKS RATHER UNEVENTFUL. A BLOCKING
RIDGE OFF THE EAST COAST WILL STALL SURFACE HIGH PRESSURE OVER NEW
ENGLAND BY MID TO LATE IN THE WEEK. A LOBE OF HIGH PRESSURE IS
EXPECTED TO LINGER OVER THE LOWER GREAT LAKES AS THIS OCCURS KEEPING
FAIR WEATHER FOR THE BULK OF THE REGION.
THERE SHOULD BE A COUPLE OF WEAK SHORT WAVES THAT TRY TO RUN INTO
THIS BLOCKING RIDGE. THE FIRST PASSES MI LATE THURSDAY OR THURSDAY
NIGHT...WITH THE SECOND ARRIVING SATURDAY. BOTH FEATURES COULD PASS
THROUGH DRY HOWEVER.
WE SHOULD SEE A SLOW MODERATION IN TEMPS THROUGH THE PERIOD WITH
UPPER 30S TO AROUND 40 FOR HIGHS ON TUESDAY...WARMING TO AROUND 50
BY SATURDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 633 PM EST SAT NOV 10 2012
THERE AT THREE IMPORTANT ISSUES TONIGHT. FIRST IS THE POTENTIAL
FOR THUNDERSTORMS WITH HAIL THIS EVENING. THE NEST ISSUE IS THE
LOW LEVEL WIND SHEAR.... WINDS NEAR 2000 FT ALG SHOULD BE ABOUT
200 DEGREES AROUND 50 KNOTS MOST OF THE NIGHT. WITH WINDS ON THE
GROUND OF 190 DEGREES AT 15 KNOTS... THAT WOULD MORE THAN CREATE
SIGNIFICANT LOW LEVEL WIND SHEAR. FINALLY THERE IS THE VERY STRONG
WINDS NEAR THE SURFACE SUNDAY. I COULD SEE SOUTH WINDS OF 25 KNOTS
GUSTING TO 35 KNOTS DURING THE LATE MORNING AND AFTERNOON.
AN AREA OF SHOWERS OVER CENTRAL LAKE MICHIGAN BACK TO SOUTHERN
WISCONSIN IS LIFTING NORTH WITH THE WARM FRONT THIS EVENING. THERE
IS CONSIDERABLE MID LEVEL INSTABILITY... IN FACT RAP SOUNDINGS FOR
MKG/GRR SHOW UP TO 700 J/KG OF ELEVATED CAPE TILL 04Z OR SO WITH
AN EQUILIBRIUM LEVEL NEAR 35000... AND THE GREATEST CAPE IS NEAR
THE -15C ISOTHERM. THIS TELLS ME HAIL IS POSSIBLE IF THESE STORMS
IN FACT DEVELOP. SO I PUT VCTS IN THE I-96 TAF GROUP TILL 04Z TO
ALLOW FOR THE WARM FRONT CONVECTION TO PASS THOUGHT THE AREA.
BEYOND THAT I ALREADY MENTIONED THE LOW LEVEL WIND SHEAR AND I
HAVE THAT IN THE TAFS UNTIL THE SUN MIXES THE BOUNDARY LAYER
AROUND 15Z. ONCE THAT HAPPENS EXPECT THOSE STRONG WINDS TO BE
CLOSER TO THE GROUND SO 20 TO 30 KNOT WINDS NEAR THE GROUND SHOULD
BE EXPECTED AT ALL TAF SITES.
THE CONVECTION WITH THE COLD FRONT SHOULD HOLD OFF UNTIL AFTER 00Z
SO NOT MUCH AN ISSUE WITH THIS SET OF TAFS.
&&
.MARINE...
ISSUED AT 345 PM EST SAT NOV 10 2012
SOUTH FLOW WILL BE INCREASING TONIGHT AND SUNDAY... WITH GUSTS TO
GALES FORCE NOW LOOKING MORE LIKELY SUNDAY. WILL CONTINUE THE SMALL
CRAFT ADVISORY TONIGHT BUT HAVE UPGRADED TO A GALE WARNING FOR
SUNDAY INTO SUNDAY EVENING WHEN THE CORE OF STRONGEST WINDS IS
IMPACTING THE NEARSHORE.
&&
.HYDROLOGY...
ISSUED AT 345 PM EST SAT NOV 10 2012
WIDESPREAD RAIN AMOUNTS OF 0.50 TO 0.75 WITH THE COLD FRONT SUNDAY
NIGHT INTO EARLY MONDAY WILL BRING ONLY SLIGHT RISES ON RIVERS WHICH
HAVE BEEN RUNNING WAY BELOW ACTION STAGE. THUS NO HYDRO ISSUES
ANTICIPATED.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 10 AM EST SUNDAY FOR LMZ844>849.
GALE WARNING FROM 10 AM TO 10 PM EST SUNDAY FOR LMZ844>849.
&&
$$
SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...JK
AVIATION...WDM
HYDROLOGY...MEADE
MARINE...MEADE
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
322 AM EST FRI NOV 9 2012
.SYNOPSIS...
ISSUED AT 322 AM EST FRI NOV 9 2012
A WARM FRONT IS EXPECTED TO DEVELOP JUST SOUTH OF THE AREA THROUGH
THIS EVENING. THE CHANCE FOR SHOWERS AND EVEN A THUNDERSTORM WILL
INCREASE THIS AFTERNOON...AND WILL BECOME LIKELY TONIGHT. WARMER AIR
WILL MOVE IN ACROSS THE AREA THEN DURING THE DAY ON SATURDAY...AND
WILL REMAIN THROUGH THE DAY ON SUNDAY. A STRONG COLD FRONT WILL MOVE
THROUGH THE AREA LATE SUNDAY NIGHT AND DURING THE DAY ON MONDAY.
THIS WILL BRING SHOWERS AND A CHANCE OF STORMS WITH IT. MUCH COLDER
AIR WILL MOVE IN FOR THE FIRST HALF OF NEXT WEEK.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 322 AM EST FRI NOV 9 2012
MAIN FOCUS OF THE SHORT TERM CONTINUES TO BE DETERMINING PCPN TRENDS
THROUGH THE UPCOMING WEEKEND. NO REAL CHANGES WERE MADE AS THE
FORECAST IS ON TRACK.
LOW CLOUDS HAVE BEEN TRYING TO MOVE OUT OF THE AREA THIS MORNING. AS
THEY TRY TO MOVE OUT...THEY HAVE BEEN BACKBUILDING AS A RESULT OF
THE STRONG WARM AND MOIST ADVECTION IN PROGRESS FROM THE SE TEXAS
COAST INTO THE GREAT LAKES REGION. THEY ARE MAINLY IMPACTING AREAS
ALONG AND NORTH OF I-96. WE COULD SEE THESE CLOUDS MOVE OUT BRIEFLY
TODAY. HOWEVER THE OVERALL TREND WILL BE TO SEE MORE MID AND HIGH
LEVEL CLOUD COVER ADVECT IN TODAY.
WE WILL SEE THE NRN PERIPHERY OF THE DEVELOPING LLJ AXIS APPROACH
THE SRN PORTION OF THE AREA LATE THIS AFTERNOON. ALL THE MODELS ARE
GENERALLY SHOWING THAT WE SHOULD SEE SOME DEVELOPMENT OF PCPN LATE
TODAY DOWN SOUTH. THE LACK OF LOW LEVEL MOISTURE WILL LIMIT THE
AMOUNT OF PCPN INITIALLY. THE THREAT FOR PCPN WILL INCREASE THIS
EVENING AS WE SEE THE DEEPER MOISTURE FINALLY IN PLACE...AND THE LOW
LEVEL JET IS AS CLOSE AS IT GETS TO THE AREA. THE THREAT WILL
GRADUALLY SHIFT NORTH THROUGH SAT AFTERNOON AS THE WARM FRONT LIFTS
NORTH.
THE THREAT OF THUNDER REMAINS AS THE MODELS ARE ALL INDICATING
ELEVATED LI/S DROPPING BELOW ZERO C. THERE IS NOT A LOT OF
INSTABILITY...BUT ENOUGH TO CONTINUE TO JUSTIFY THE MENTION OF
THUNDER IN THE FCST.
WE SHOULD SEE LITTLE TO NO PCPN IN THE PERIOD FROM LATE SAT
AFTERNOON UNTIL LATE SUN AFTERNOON. THE WARM FRONT WILL BE WELL
NORTH OF THE AREA BY SAT EVENING...AND THE UPPER RIDGE AXIS IS
ACTUALLY ALMOST OVERHEAD. WE CAN NOT RULE OUT A RANDOM SHOWER OR
STORM DURING THIS PERIOD AS WE COULD SEE EMBEDDED SHORT WAVES IN THE
FLOW POTENTIALLY KICK SOMETHING OFF. WE WILL BE IN THE WARM
SECTOR...AND SHOULD SEE TEMPS JUMP INTO THE 60S DURING THE DAY ON
SAT AND SUN.
WE WILL SEE THE CHC OF RAIN INCREASE LATE SUN AFTERNOON TO THE WEST.
THIS OCCURS AS WE SEE THE COLD FRONT AND THE LONG WAVE TROUGH MAKE A
RUN FOR THE CWFA. IT IS LOOKING LIKE THE MAJORITY OF THE RAIN WILL
HOLD OFF UNTIL SUN NIGHT WHEN THE FRONT AND UPPER WAVE WILL BE MUCH
CLOSER. INSTABILITY IS LACKING...SO ANY KIND OF SEVERE THREAT IS
QUITE LIMITED.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 322 AM EST FRI NOV 9 2012
NO SIGNIFICANT CHANGES TO THE FORECAST. CONSISTENT MODEL AGREEMENT
ON TIMING THE COLD FROPA THROUGH FOR LATE SUNDAY NIGHT INTO MONDAY
AND THIS IS WHEN THE HIGHEST POPS WILL BE. SHARP COLD FRONT COULD
SEE BAND OF HEAVIER RAIN AHEAD OF IT WITH SOME LINGERING SNOW
SHOWERS ON THE BACK SIDE.
KEPT THUNDER ON SUNDAY NIGHT CONFINED TO THE SOUTHWEST FORECAST AREA
TO MESH WITH SURROUNDING OFFICES. INSTABILITY IS LIMITED BUT A
RUMBLE OF THUNDER CANNOT BE RULED OUT. LIKELY POPS SUNDAY NIGHT FOR
ALL BUT THE SE FORECAST AREA AND LIKELY POPS ALL ZONES ON MONDAY.
CHANGEOVER TO SNOW EXPECTED MONDAY NIGHT AS SHARP THERMAL TROUGH
MOVES IN WITH 850MB TEMPS FALLING BELOW MINUS 10C BY TUESDAY. THIS
WILL AID LAKE EFFECT AND LINGERING SNOW SHOWERS SHOULD WIND DOWN
TUESDAY AND END TUESDAY NIGHT AS SFC HIGH BUILDS IN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1148 PM EST THU NOV 8 2012
THE LOW CLOUDS ARE STARTING TO CLEAR NEAR AND SOUTH OF INTERSTATE
94 BUT NEAR INTERSTATE 96... THE CLOUDS SEEM TO WANT TO REDEVELOP
OFF SHORE OF MKG AND MOVE INLAND. LOOKING AT THE RAP AND NAM12
FROM 00Z IT WOULD SEEM THE LOW CLOUDS WILL HAVE A HARD TIME REALLY
CLEARING NEAR AND NORTH OF INTERSTATE 96 BEFORE 09Z SO I HELP THE
CLOUDS IN THERE TILL THEN. I EXPECT MVFR VSBY FOR MOST OF THE
INLAND TAF SITES.
THE DEVELOPING WARM FRONT SHOULD RESULT IN SHOWERS DEVELOPING
FRIDAY NIGHT SO I PUT THEM IN THE TAF AFTER 00Z.
&&
.MARINE...
ISSUED AT 322 AM EST FRI NOV 9 2012
THE MAIN PERIOD OF CONCERN FOR MARINE INTERESTS WILL BE FROM
SATURDAY THROUGH MONDAY AS WINDS INCREASE IN ASSOCIATION WITH A
STRONG STORM SYSTEM THAT WILL EVENTUALLY MOVE THROUGH THE AREA.
SMALL CRAFT ADVISORIES LOOK LIKE A SURE THING. THERE IS SOME
POTENTIAL FOR GALES WITH STRONG WINDS ONLY 1-2K FEET UP. THE STRONG
CORE OF WINDS SHOULD REMAIN ELEVATED DUE TO THE STRONG WARM AIR
MOVING IN OVER THE RELATIVELY COOLER WATERS.
&&
.HYDROLOGY...
ISSUED AT 322 AM EST FRI NOV 9 2012
WE CONTINUE TO EXPECT THAT WE WILL NOT HAVE ANY HYDROLOGY ISSUES
THROUGH MID WEEK NEXT WEEK. RIVER LEVELS REMAIN AROUND AVERAGE...AND
WE DO NOT SEE A GOOD POTENTIAL FOR HEAVY RAINS. THIS INCLUDES THE
TWO PERIODS OF RAIN EXPECTED THROUGH MONDAY MORNING.
THE TREND HAS BEEN FOR A LITTLE LESS RAINFALL EXPECTED WITH THE
DEVELOPMENT OF THE WARM FRONT LATER TODAY AND THROUGH SATURDAY
AFTERNOON. MOST LOCATIONS SHOULD GENERALLY SEE LESS THAN A QUARTER
OF AN INCH.
THE OTHER PERIOD OF RAINFALL WILL COME ALONG THE STRONG COLD FRONT
SUNDAY NIGHT AND MONDAY. WE CONTINUE TO EXPECT RAINFALL AMOUNTS WILL
BE BETWEEN A QUARTER AND THREE QUARTERS OF AN INCH OF RAINFALL.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...OSTUNO
AVIATION...WDM
HYDROLOGY...NJJ
MARINE...NJJ
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1148 PM EST THU NOV 8 2012
.SYNOPSIS...
ISSUED AT 345 PM EST THU NOV 8 2012
A WARM FRONT WILL LIFT NORTH INTO SOUTHERN LOWER MICHIGAN BRINGING
MILDER TEMPERATURES FOR THE COMING WEEKEND. THE FRONT WILL ALSO
CREATE A THREAT OF SHOWERS AND THUNDERSTORMS FRIDAY NIGHT INTO
SATURDAY.
THE WARM FRONT WILL LIFT NORTH OF THE REGION SATURDAY NIGHT AND
TEMPORARILY END THE CHANCE OF RAIN... BUT A COLD FRONT APPROACHING
FROM THE WEST WILL BRING ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS
SUNDAY NIGHT INTO EARLY MONDAY. COLD AIR WILL RETURN AGAIN BEHIND
THAT COLD FRONT FOR NEXT WEEK AND SOME SNOW FLAKES MAY BE SEEN AS
WELL.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 345 PM EST THU NOV 8 2012
A STUBBORN AREA OF STRATUS HAS BEEN IMPACTING THE GRR CWFA TODAY...
AND THE QUESTION NOW BECOMES WHAT HAPPENS WITH THESE CLOUDS TONIGHT.
THE CLOUDS SEEM TO BE FAIRLY CLOSELY LINKED WITH THE 925 AND 850 MB
THERMAL TROUGH... WHICH IS PROGGED TO MOVE EAST AFTER 06Z AS THE
WARM AIR PUSHES IN FROM THE SOUTHWEST. USING THE LOW LEVEL THERMAL
TROUGH AS A PROXY FOR THE CLOUD BEHAVIOR... WILL HAVE MOSTLY CLOUDY
THIS EVENING THEN GO WITH SKIES BECOMING PARTLY CLOUDY AFTER
MIDNIGHT.
BELIEVE FRIDAY MORNING WILL START OUT WITH ABUNDANT SUNSHINE... BUT
INCREASING CLOUDS ARE LIKELY IN THE AFTERNOON AS THE WARM FRONT
MOVES IN. ALSO ADDED A SLIGHT CHANCE OF LIGHT RAIN SHOWERS LATE IN
THE DAY DUE TO LOWERING CPD/S AND INCREASING MOISTURE/THETA-E
CONVERGENCE NORTH OF THE SHARPENING WARM FRONT.
LOOKS LIKE A PRETTY GOOD CHANCE OF SHOWERS AND TSTMS ON FRIDAY NIGHT
INTO SATURDAY WITH 30+ KT SWLY LOW LEVEL JET AIMED INTO SRN MICHIGAN
ALONG THE WEST-EAST ORIENTED WARM FRONT AND PWAT VALUES EXCEEDING
ONE INCH. PROGGED 850 TO 500 MB THETA LAPSE RATES OF ZERO TO -3
INDICATE A DECENT POTENTIAL FOR ELEVATED CONVECTION/TSTMS.
COVERAGE/FREQUENCY OF CONVECTION WILL PROBABLY DECREASE HEADING INTO
LATE SATURDAY AND SATURDAY NIGHT AS THE WARM FRONT LIFTS NORTH.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 345 PM EST THU NOV 8 2012
UNSEASONABLY WARM CONDITIONS ARE ANTICIPATED SUNDAY IN STRONG
SOUTHERLY FLOW WAA IN ADVANCE OF THE APPROACHING COLD FRONT. MAX
TEMPS WILL REACH WELL INTO THE 60S. A SHOWER OR TWO IS POSSIBLE
DURING THE DAY BUT THE VAST MAJORITY OF THE DAY SHOULD BE DRY UNTIL
THE COLD FRONT BRINGS RAIN AND A SLIGHT CHANCE OF THUNDERSTORMS LATE
SUNDAY NIGHT.
POST FRONTAL RAIN WILL LINGER MONDAY FOLLOWED BY MIXED RAIN AND SNOW
SHOWERS LATE MONDAY/MONDAY NIGHT AS H8 TEMPS FALL TO -8 TO -10 C BY
12Z TUE ALONG WITH EXTENSIVE LINGERING LOW TO MID LEVEL MOISTURE. A
FEW LIGHT SNOW SHOWERS/FLURRIES MAY LINGER INTO TUESDAY MORNING
BEFORE SFC RIDGING/ANTICYCLONIC FLOW BRINGS DRY BUT COOL WEATHER
LATE TUESDAY THROUGH WEDNESDAY.
FAIR WX WILL CONTINUE INTO LATE WEEK WITH THE RIDGE STILL IN CONTROL
ALONG WITH A GRADUAL MODERATING TREND OF TEMPS LATE NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1148 PM EST THU NOV 8 2012
THE LOW CLOUDS ARE STARTING TO CLEAR NEAR AND SOUTH OF INTERSTATE
94 BUT NEAR INTERSTATE 96... THE CLOUDS SEEM TO WANT TO REDEVELOP
OFF SHORE OF MKG AND MOVE INLAND. LOOKING AT THE RAP AND NAM12
FROM 00Z IT WOULD SEEM THE LOW CLOUDS WILL HAVE A HARD TIME REALLY
CLEARING NEAR AND NORTH OF INTERSTATE 96 BEFORE 09Z SO I HELP THE
CLOUDS IN THERE TILL THEN. I EXPECT MVFR VSBY FOR MOST OF THE
INLAND TAF SITES.
THE DEVELOPING WARM FRONT SHOULD RESULT IN SHOWERS DEVELOPING
FRIDAY NIGHT SO I PUT THEM IN THE TAF AFTER 00Z.
&&
.MARINE...
ISSUED AT 345 PM EST THU NOV 8 2012
WHILE THE SOUTHERLY FLOW WILL BE INCREASING TONIGHT... IT APPEARS
THAT CONDITIONS WILL REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA. THE
BEST CHANCE OF SEEING ADVISORY CRITERIA WINDS AND WAVES WILL BE LATE
SATURDAY INTO SATURDAY NIGHT WHEN THE SFC WARM FRONT LIFTS OFF TO
THE NORTH.
&&
.HYDROLOGY...
ISSUED AT 345 PM EST THU NOV 8 2012
EXPECTED QPF WITH THE WARM FRONT FRIDAY NIGHT AND SATURDAY IS 0.10
TO 0.25 AND LOCALLY HIGHER AMOUNTS TO 0.50. EXPECTED QPF AMOUNTS
WITH THE COLD FRONT SUNDAY NIGHT INTO EARLY MONDAY SHOULD BE 0.25 TO
0.75 WITH UP TO AN INCH POSSIBLE. NO HYDRO ISSUES ARE FORESEEN WITH
THESE QPF AMOUNTS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...LAURENS
AVIATION...WDM
HYDROLOGY...MEADE
MARINE...MEADE
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1126 AM CST FRI NOV 9 2012
.AVIATION...18Z TAF. MAIN FORECAST CONCERN LIES WITH THE
CONTINUING CLOUD COVER THIS AFTERNOON...AND INCREASING WINDS
TOWARD THE END OF THE TAF PERIOD AHEAD OF AN APPROACHING COLD
FRONT. BATCH OF LOW LEVEL STRATUS CONTINUES TO AFFECT THE
TERMINAL AREA...AND EVEN WITH SATELLITE IMAGERY SHOWING THE
ERN/WRN EDGES STARTING TO ERODE...LOWERED CIG HEIGHTS SHOULD
REMAIN FOR AT LEAST ANOTHER COUPLE OF HRS. ONCE THE STRATUS DOES
ERODE...NOT EXPECTED CLOUD COVER TO CAUSE ANY OTHER ISSUES THROUGH
THE TAF PERIOD. AM A LITTLE CONCERNED ABOUT THE POTENTIAL FOR SOME
FOG LATER TONIGHT...MAINLY IN THE AREAS SEEING STRATUS TODAY AND
WHERE WINDS WILL BE LIGHTER FOR A PERIOD AS A WARM FRONT BOUNDARY
PUSHES NORTH...AND DECIDED TO INSERT A MVFR VISIBILITY MENTION.
AFTER SUNRISE...SOUTHERLY WINDS WILL BE ON THE INCREASE THROUGH
THE END OF THE TAF PERIOD...LOOKING TO ALREADY BE GUSTING NEAR 30
MPH BY 18Z.
&&
PREV DISCUSSION... /ISSUED 445 AM CST FRI NOV 9 2012/
SHORT TERM...THROUGH 12Z MONDAY. OVERNIGHT UPPER AIR ANALYSIS
INDICATES LONG WAVE TROUGHING OVER THE WESTERN AND EASTERN
CONUS...AND A RIDGE PREVAILING OVER THE CENTRAL CONUS. A CLOSED
MID LEVEL LOW IS ALSO NOTED OVER THE NORTHWESTERN CONUS...WITH
ANOTHER CLOSED MID LEVEL CIRCULATION OVER THE NORTHEASTERN CONUS.
MID AND UPPER LEVEL JET ENERGY EXTENDS FROM CALIFORNIA...NORTHEAST
INTO THE NORTHERN PLAINS AND SOUTH CENTRAL CANADA...AND THEN
SOUTHEAST ACROSS THE OHIO VALLEY AND ON INTO THE SOUTHEASTERN
CONUS. TROPOSPHERIC FLOW IS NOT OVERLY STRONG NEAR OUR AREA AS A
RESULT...MAXING OUT AT AROUND 50KTS AT VARIOUS POINTS BETWEEN
500MB AND 200MB PER 00Z SOUNDING DATA FROM KLBF. WATER VAPOR
IMAGERY CLEARLY SHOWS THE CLOSED MID LEVEL LOWS OVER THE
NORTHWESTERN AND NORTHEASTERN CONUS. INCREASING VALUES OF MID
LEVEL MOISTURE ARE ALSO NOTED ON WATER VAPOR IMAGERY ADVECTING
NORTHEAST ALONG THE FRONT OF THE LONG WAVE TROUGH...INTO THE ROCKY
MOUNTAIN RANGE AND PLAINS. SOME OF THIS MID LEVEL MOISTURE IS
PROMOTING INCREASING MID TO HIGH LEVEL CLOUD COVER OVER PORTIONS
OF THE CENTRAL PLAINS. AT THE SURFACE A STATIONARY BOUNDARY IS
NOTED EXTENDING FROM WESTERN IOWA...SOUTHWEST INTO NORTHEASTERN
KANSAS AND ON INTO SOUTHEASTERN COLORADO. THE LOW LEVEL WIND FIELD
ACROSS OUR AREA REMAINS FROM THE NORTH AS A RESULT...BUT IS FAIRLY
LIGHT AT AROUND 5KTS. IN ADDITION TO THE AFOREMENTIONED MID TO
HIGH LEVEL CLOUDS BEGINNING TO WORK INTO THE REGION...SATELLITE
IMAGERY ALSO INDICATES A STRATUS DECK OVER MUCH OF THE NORTHERN
PLAINS...WITH THIS DECK MOVING SOUTH/SOUTHEAST AT AROUND 20KTS AND
ALREADY INFILTRATING PORTIONS OF CENTRAL NEBRASKA.
GUIDANCE FROM THE NAM...RAP...AND OPERATIONAL GFS ALL SUGGEST
ISENTROPIC UPGLIDE AND SATURATION...PRIMARILY ALONG THE 290-295K
SURFACES...WILL CONTINUE TO PROMOTE STRATUS OVER PORTIONS OF THE
REGION THROUGH MIDDAY. THERE IS SOME UNCERTAINTY AS TO HOW FAR
SOUTH THIS STRATUS DECK WILL MOVE ACROSS OUR CWA. THE OPERATIONAL
GFS REMAINS THE MOST AGGRESSIVE IN BRINGING THE DECK ACROSS OUR
ENTIRE CWA...WHILE THE NAM AND RAP BOTH SUGGEST THE NORTHERN HALF
OF OUR CWA WILL BE THE ONLY LOCATIONS TO OBSERVE THIS STRATUS.
SATELLITE IMAGERY INDICATES THE STRATUS DECK HAS SLOWED THROUGH
THE PAST 2-3 HOURS AND IT NOW SEEMS UNLIKELY THIS STRATUS WILL
MAKE IT TO OUR KANSAS COUNTIES BY 12Z...WHICH IS WHAT THE
OPERATIONAL GFS SUGGESTS. GIVEN THIS...OPTED TO PLAY CLOSER TO NAM
AND RAP GUIDANCE BY KEEPING THE FORECAST STRATUS PRIMARILY OVER
THE NORTHERN HALF OF THE CWA. GUIDANCE FROM THE NAM AND RAP ALSO
SUGGEST THE LOW LEVEL BAROCLINIC ZONE TO OUR SOUTH/SOUTHEAST WILL
LIFT NORTH AS A WARM FRONT TODAY...THUS CARRYING THE PRIMARY AXIS
OF ISENTROPIC UPGLIDE FARTHER NORTH WHICH SHOULD HELP CLEAR THE
STRATUS FROM MUCH OF OUR CWA BY MIDDAY. ALTHOUGH THE INCREASING
MID AND HIGH LEVEL CLOUDS MAY KEEP TEMPERATURES FROM MEETING THEIR
FULL DIURNAL POTENTIAL TODAY...THERE SHOULD BE ENOUGH DIABATIC
HEATING FOR 20-25 DEGREE TEMPERATURE RISES WHICH SHOULD PRESENT
AFTERNOON HIGHS GENERALLY IN THE 60S AND 70S...WITH THE ONLY
EXCEPTION BEING ACROSS OUR FAR NORTH WHERE THE STRATUS MAY KEEP
TEMPERATURES IN THE 50S.
THE BIG WEATHER STORY CONTINUES TO REVOLVE AROUND THE INCOMING
SYSTEM FOR THIS WEEKEND. GUIDANCE CONTINUES TO SUGGEST THE MID
LEVEL LOW...CURRENTLY OVER THE NORTHWESTERN CONUS...WILL OPEN UP
INTO A WAVE AND MOVE EAST INTO THE CENTRAL CONUS TONIGHT THROUGH
SUNDAY. AS THE MID LEVEL TROUGH APPROACHES FROM THE
WEST...RESULTANT SURFACE CYCLOGENESIS IS EXPECTED TO COMMENCE OVER
THE HIGH PLAINS OF NORTHEASTERN COLORADO OVERNIGHT TONIGHT. THIS
SURFACE LOW IS THEN EXPECTED TO QUICKLY EJECT NORTHEAST ACROSS THE
CENTRAL PLAINS AS THE MID LEVEL TROUGH AXIS APPROACHES OUR AREA
FROM THE WEST. AS THE SURFACE LOW MOVE NORTHEAST...AN ASSOCIATED
COLD FRONT IS EXPECTED TO SWEEP ACROSS OUR AREA SATURDAY AFTERNOON
INTO SATURDAY NIGHT.
QPF FIELDS FROM THE NAM...OPERATIONAL GFS...EC AND SREF-MEAN ALL
SUGGEST MID LEVEL THERMAL ADVECTION AHEAD OF THE MID LEVEL TROUGH
AXIS...WORKING IN CONCERT WITH LOW LEVEL CONVERGENCE ALONG THE LOW
LEVEL BAROCLINIC ZONE...WILL PROVIDE SUFFICIENT LIFT FOR
CONVECTIVE INITIATION NEAR THE BAROCLINIC ZONE SATURDAY AFTERNOON.
AT THIS TIME IT APPEARS THIS CONVECTION WILL INITIALIZE IN THE
VICINITY OF A LINE EXTENDING FROM FULLERTON...TO GRAND ISLAND...TO
PHILLIPSBURG. INCREASED VALUES OF LOW LEVEL MOISTURE AHEAD OF THE
LOW LEVEL BAROCLINIC ZONE...ALONG WITH INCREASING MID LEVEL LAPSE
RATES WITH THE APPROACH OF THE MID LEVEL TROUGH AXIS...SHOULD BE
SUFFICIENT ENOUGH TO PROVIDE 0-1MLCAPE VALUES ON THE ORDER OF
1000J/KG PER THE NAM AND OPERATIONAL GFS. IN ADDITION TO THE
POTENTIAL INSTABILITY...INCREASING MID AND UPPER LEVEL JET ENERGY
WILL ALSO LIKELY PROVIDE DEEP LAYER BULK SHEAR VALUES IN EXCESS
50KTS ACROSS MUCH OF THE REGION. ALSO...FORECAST PROXIMITY
SOUNDINGS FROM ACROSS THE CWA...PER THE NAM...SUGGEST A VEERING
LOW LEVEL WIND PROFILE FOR LOCATIONS STILL AHEAD OF THE LOW LEVEL
BAROCLINIC ZONE...WITH THE NAM ALSO SUGGESTING 0-1KM SRH WILL
APPROACH 300M^2/S^2 ACROSS EAST/SOUTHEASTERN PORTIONS OF OUR CWA.
NOW...INCREASING MID AND HIGH LEVEL CLOUDS WILL LIKELY KEEP
DIABATIC HEATING DOWN A TOUCH THROUGH MUCH OF THE DAY WHICH WILL
HELP SUSTAIN SOMETHING OF A CAPPING INVERSION...WHICH MEANS
INITIAL CONVECTIVE DEVELOPMENT COULD BE IN THE FORM OF A FEW
DISCRETE CELLS IN THE VICINITY OF THE LOW LEVEL BAROCLINIC ZONE.
GIVEN THE VERY STRONG DEEP LAYER BULK SHEAR...SUPER CELL
DEVELOPMENT WILL BE MORE THAN POSSIBLE AND GIVEN THIS...WILL
CONTINUE OUTLOOKING LARGE HAIL IN THE HWO. ADDITIONAL CONVECTIVE
DEVELOPMENT ALONG THE BAROCLINIC ZONE COULD THEN POTENTIALLY
EVOLVE INTO A QLCS WITH STRONG OUTFLOW WINDS AT THE SURFACE
REMAINING VERY POSSIBLE. WILL CONTINUE TO CARRY SEVERE
THUNDERSTORM WIND WORDING IN HWO AS WELL. FINALLY...GIVEN THE LOW
LEVEL SHEAR AS INDICATED BY THE NAM...WILL ALSO GO AHEAD AND
MENTION ISOLATED TORNADIC DEVELOPMENT IN ASSOCIATION WITH THE
INITIAL CONVECTION DURING THE LATE AFTERNOON HOURS.
STRONG WINDS WILL NOT ONLY BE A THREAT WITH AFTERNOON AND EVENING
THUNDERSTORM ACTIVITY ON SATURDAY...BUT STRONG SYNOPTIC WINDS WILL
ALSO BE OBSERVED ACROSS MUCH OF THE CWA SATURDAY. AS SURFACE
CYCLOGENESIS CONTINUES ACROSS THE HIGH PLAINS SATURDAY...THE LOW
LEVEL PRESSURE GRADIENT IS EXPECTED TO INTENSIFY GREATLY HEADING
INTO SATURDAY AFTERNOON...ESPECIALLY ACROSS THE SOUTHEASTERN ONE-
HALF OF THE CWA. IN ADDITION...FORECAST PROXIMITY SOUNDINGS FROM
ACROSS OUR CWA PER THE NAM AND OPERATIONAL GFS SUGGEST BOUNDARY
LAYER MIXING TO BETWEEN 850MB AND 800MB WILL BE REALIZED...WHICH
IS WHERE ~50KT WINDS WILL BE WAITING FOR TRANSPORT TO THE SURFACE.
INTERESTING TO NOTE THAT BOTH MET AND MAV GUIDANCE SUGGEST
PORTIONS OF OUR CWA WILL HIT WIND ADVISORY CRITERIA AT SOME POINT
DURING THE DAY SATURDAY...WITH MAV GUIDANCE SUGGESTING OUR
SOUTHWEST WILL HIT BETWEEN 18Z AND 21Z...AND THE NAM SUGGESTING
OUR SOUTHEAST WILL HIT CLOSER TO 00Z. RATHER THAN BLANKET A
MAJORITY OF OUR CWA WITH WIND ADVISORY WINDS...OPTED TO KEEP WINDS
JUST UNDER WIND ADVISORY ACROSS THE SOUTHEASTERN HALF OF THE CWA
WITH THE HOPES THAT WE WILL BE ABLE TO FINE-TUNE THE WIND FORECAST
AND INCREASE WINDS SOMEWHAT...INTO WIND ADVISORY CRITERIA...FOR
PORTIONS OF THE CWA ONCE THAT FORECAST BECOMES MORE CLEAR. WILL GO
AHEAD AND CONTINUE TO CARRY STRONG SYNOPTIC WIND WORDING IN THE
HWO FOR SATURDAY AFTERNOON. STRONG SYNOPTIC WINDS WILL NOT ONLY BE
A THREAT SATURDAY AFTERNOON...BUT WILL ALSO BE POSSIBLE SATURDAY
NIGHT INTO EARLY SUNDAY MORNING AFTER THE LOW LEVEL BAROCLINIC
ZONE CLEAR THE AREA. INTENSE LOW LEVEL PRESSURE RISES POST-FROPA
WILL PROMOTE YET ANOTHER INCREASE IN THE LOW LEVEL PRESSURE
GRADIENT ACROSS THE CWA 00Z-12Z SUNDAY...WITH GUIDANCE SUGGESTING
~20KT SUSTAINED WINDS WILL BE REALIZED ACROSS MUCH OF THE AREA.
WILL GO AHEAD AND CONTINUE CARRYING STRONG SYNOPTIC WIND WORDING
IN THE HWO FOR SATURDAY NIGHT/SUNDAY MORNING AS A RESULT.
WITH THE INFILTRATION OF A MUCH COLDER LOW LEVEL
AIRMASS...FORECAST PROXIMITY SOUNDINGS FROM THE ACROSS THE CWA PER
THE NAM...OPERATIONAL GFS AND EC ALL SUGGEST THE LOWER TROPOSPHERE
WILL BECOME SUPPORTIVE FOR SNOW ACROSS MUCH OF THE CWA SATURDAY
NIGHT INTO SUNDAY MORNING. AT THIS TIME IT APPEARS ANY
PRECIPITATION BEHIND THE LOW LEVEL BAROCLINIC WILL REMAIN FAIRLY
LIGHT ACROSS OUR CWA...THUS ANY SNOWFALL ACCUMULATIONS ACROSS OUR
CWA SHOULD REMAIN UNDER AN INCH. LOCATIONS WEST OF HIGHWAY 281 AND
NORTH OF I-80...WHICH IS WHERE THE LOW LEVEL COLD AIR ADVECTION
WILL BE FIRST TO INFILTRATE...SEEM MOST LIKELY TO OBSERVE THE MOST
SNOWFALL ACCUMULATION. IT IS WORTH NOTING THAT A FEW FORECAST
PROXIMITY SOUNDINGS SUGGEST A BRIEF PERIOD OF SLEET NEAR THE TRI-
CITIES AREA AS THE TRANSITION FROM RAIN TO SNOW BEGINS...BUT GIVEN
THE UNCERTAINTY AND BREVITY OF ANY SUCH POTENTIAL ACTIVITY...OPTED
TO HOLD OFF FROM MENTIONING THIS IN THE FORECAST FOR THE TIME
BEING.
FINALLY...TEMPERATURES LOOK TO FALL OFF DRAMATICALLY POST-FROPA
HEADING INTO SATURDAY NIGHT...AND WITH CONTINUED LOW LEVEL COLD
AIR ADVECTION AND LINGERING CLOUD COVER DURING THE DAY
SUNDAY...ITS DOUBTFUL TEMPERATURES WILL GO MUCH OF ANYWHERE DURING
THE DAY SUNDAY. LOWS IN THE MID 20S TO MID 30S ARE CURRENTLY
FORECAST FOR SATURDAY NIGHT...WITH TEMPERATURES STRUGGLING THROUGH
THE 30S DURING THE DAY SUNDAY. THE PASSAGE OF THE SURFACE RIDGE
AND THE INTRODUCTION OF LOW LEVEL RETURN FLOW SHOULD THEN PRESENT
A WARMING TREND TO FINISH OUT THE SHORT TERM FORECAST PERIOD.
FIRE WEATHER...A LOW LEVEL BAROCLINIC ZONE IS EXPECTED TO CLEAR
WESTERN PORTIONS OF OUR CWA BY LATE MORNING OR MIDDAY SATURDAY.
ALTHOUGH LOW LEVEL COLD AIR ADVECTION WILL BEGIN PUSHING INTO THE
AREA SHORTLY AFTER FROPA...THERE WILL BE A BRIEF PERIOD IN WHICH
LOW LEVEL DRY AIR ADVECTION WILL OUTWEIGH THE COLD AIR
ADVECTION...THUS ALLOWING LOW LEVEL RELATIVE HUMIDITY TO PLUMMET
AS WE HEAD INTO THE AFTERNOON HOURS SATURDAY. AT THIS TIME IT
APPEARS LOCATIONS GENERALLY WEST OF HIGHWAY 281 AND SOUTH OF I-80
WILL OBSERVE THE LOWEST RELATIVE HUMIDITY VALUES...SOMEWHERE NEAR
25%. THESE LOW VALUES OF RELATIVE HUMIDITY...WORKING IN CONCERT
WITH A STRONG LOW LEVEL WIND FIELD...SUSTAINED WELL ABOVE 17KTS
AND GUSTS WELL ABOVE 22KTS...WILL PROVIDE AN ELEVATED FIRE WEATHER
DANGER SATURDAY AFTERNOON. AS A RESULT...WILL GO AHEAD AND PRESENT
ELEVATED FIRE WEATHER WORDING IN THE FWF AND HWO.
LONG TERM...MONDAY THROUGH THURSDAY
THE MAIN THEME: ANOMALOUS "MID-WINTER"LIKE COLD EASES WITH TEMPS
REBOUNDING TO NORMAL AS FAVORABLE PATTERN DELIVERS ANOTHER PCPN
EVENT NEXT THU NGT-FRI AND MORE IN THE OFFING AFTER THAT.
HAZARDS: NONE FORESEEN ATTM. HOWEVER OUR CURRENT MIN RH IS FCST
AROUND 25% NEXT WED. IF WINDS END UP BREEZIER THAN CURRENTLY
EXPECTED...CAN SEE THIS BEING A DAY OF ELEVATED FIRE DANGER.
BIG PICTURE: BELIEVE OVERALL PATTERN CONTINUES TO SUGGEST MORE
RAIN IN OUR FUTURE...ESPECIALLY ALONG AND E OF HWY 281. THE NAO
WILL TRANSITION TO ITS POSITIVE PHASE NEXT WEEK WITH THE PNA
REMAINING NEGATIVE. THIS PHASE CONFIGURATION WILL BE SUPPORTIVE OF
AN ERN USA RIDGE/WRN USA TROF THRU MID-MONTH AND DELIVERS AT LEAST
TWO MORE FORESEEABLE CHANCES FOR PCPN. OVERALL...TEMPS WILL
AVERAGE NEAR NORMAL THRU NEXT THU.
QPF: THE NEXT DECENT OPPORTUNITY CONTS TO BE OUTLOOKED FOR NEXT
THU NGT-FRI /15TH-16TH/. MODELS ARE STRUGGLING WITH RUN-TO-RUN
CONSISTENCY ON HOW POTENT TO KEEP THE UPPER-LEVEL SYSTEM. THE 00Z
EC ENSEMBLE MEAN SHOWS SOME SPREAD AT THE BASE OF THE TROF. THIS
HAS IMPLICATIONS FOR PCPN AMTS. IF THE UPPER SYSTEM REMAINS
OPEN...IT WILL MOVE THRU FASTER WITH LESS OF AN OPPORTUNITY FOR
PCPN. WE`RE HOPING IT REMAINS CLOSED AS WE STRUGGLE TO EVEN
MAINTAIN NORMAL PCPN AMTS. ONCE THIS SYSTEM DEPARTS...WE GET
ANOTHER QUIET INTERLUDE NEXT WEEKEND. THEN WE LOOK TO THE 19TH-
20TH FOR THE NEXT TROF AND RAIN POTENTIAL.
THE DAILY DETAILS...
MON: THE UPPER TROF/CORE OF THE COLDEST AIR DEPARTS INTO THE MS
VALLEY...ALLOWING TEMPS TO EASE UPWARD. HIGH PRES AT THE SFC.
AFTER A BONE-CHILLING START WITH MOST PLACES IN THE TEENS...A NICE
BUT STILL CHILLY DAY.
TUE: LOW AMPLITUDE SHORTWAVE RIDGE WITH STRONG HIGH PRES OVER THE
ERN USA. THIS HIGH REMAINS PARKED THERE THRU THE REST OF THE WEEK
WITH A TENDENCY TO DRIFT TOWARD NEW ENGLAND. SUNNY. TEMPS RETURN
TO NEAR NORMAL /NOW ONLY IN THE LOWER 50S/.
WED: THE TRAILING END OF A WEAK COOL FRONT MOVES THRU LATE. THIS
MAY END UP MORE OF A WINDSHIFT LINE. ALL QG FORCING/MSTR WILL BE
FAR TO THE N. DRY WITH SEASONAL/NORMAL TEMPS. MORE BREEZY AS LEE
LOW DEVELOPS OVER CO...INTENSIFYING THE GRADIENT.
THU: NW FLOW/SHORTWAVE RIDGING AS PAC TROF MOVES INTO DESERT SW.
INCREASING CLOUDS AND BREEZY.
FRI: UPPER TROF EJECTS INTO SRN/CNTRL PLAINS. RAIN LOOKING
PROBABLE AND MAY BEGIN THU NGT. GFS ENSEMBLE PCPN PROBABILITIES
ARE HIGH WITH A 70% CHANCE FOR .10 IN 24 HRS WITH POTENTIAL FOR
MORE.
COOLER WITH TEMPS PROBABLY HELD DOWN IN THE 40S.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HASTINGS NE
520 AM CST FRI NOV 9 2012
.AVIATION...12Z KGRI TAF. ANOTHER HOUR OR TWO OF VFR CONDITIONS
REMAIN POSSIBLE...BUT PREVAILING IFR CONDITIONS ARE FORECAST 13Z-
17Z...WITH TEMPORARY LIFR CONDITIONS ALSO FORECAST. VFR CONDITIONS
ARE THEN EXPECTED 17Z ONWARD. SATELLITE IMAGERY INDICATES A
STRATUS DECK APPROACHING KGRI FROM THE NORTH AND GIVEN THE CURRENT
MOTION OF THIS DECK...CEILINGS BELOW 1000FT AGL SHOULD BE REALIZED
BY 13Z. GUIDANCE SUGGESTS THIS STRATUS SHOULD SLOW AND ACTUALLY
BEGIN RETROGRADING TO THE NORTH A LITTLE LATER THIS MORNING...WITH
VFR CONDITIONS RESTORED BY 17Z. THE SURFACE WIND WILL REMAIN
GENERALLY LIGHT AND VARIABLE DURING THE TAF PERIOD. THIS LIGHT
WIND...WORKING IN CONCERT WITH DECREASING LOW LEVEL DEWPOINT
DEPRESSIONS...MAY ALSO PROMOTE A PERIOD OF RESTRICTED VISIBILITIES
IN BR...13Z-17Z.
&&
.PREV DISCUSSION... /ISSUED 445 AM CST FRI NOV 9 2012/
SHORT TERM...THROUGH 12Z MONDAY. OVERNIGHT UPPER AIR ANALYSIS
INDICATES LONG WAVE TROUGHING OVER THE WESTERN AND EASTERN
CONUS...AND A RIDGE PREVAILING OVER THE CENTRAL CONUS. A CLOSED
MID LEVEL LOW IS ALSO NOTED OVER THE NORTHWESTERN CONUS...WITH
ANOTHER CLOSED MID LEVEL CIRCULATION OVER THE NORTHEASTERN CONUS.
MID AND UPPER LEVEL JET ENERGY EXTENDS FROM CALIFORNIA...NORTHEAST
INTO THE NORTHERN PLAINS AND SOUTH CENTRAL CANADA...AND THEN
SOUTHEAST ACROSS THE OHIO VALLEY AND ON INTO THE SOUTHEASTERN
CONUS. TROPOSPHERIC FLOW IS NOT OVERLY STRONG NEAR OUR AREA AS A
RESULT...MAXING OUT AT AROUND 50KTS AT VARIOUS POINTS BETWEEN
500MB AND 200MB PER 00Z SOUNDING DATA FROM KLBF. WATER VAPOR
IMAGERY CLEARLY SHOWS THE CLOSED MID LEVEL LOWS OVER THE
NORTHWESTERN AND NORTHEASTERN CONUS. INCREASING VALUES OF MID
LEVEL MOISTURE ARE ALSO NOTED ON WATER VAPOR IMAGERY ADVECTING
NORTHEAST ALONG THE FRONT OF THE LONG WAVE TROUGH...INTO THE ROCKY
MOUNTAIN RANGE AND PLAINS. SOME OF THIS MID LEVEL MOISTURE IS
PROMOTING INCREASING MID TO HIGH LEVEL CLOUD COVER OVER PORTIONS
OF THE CENTRAL PLAINS. AT THE SURFACE A STATIONARY BOUNDARY IS
NOTED EXTENDING FROM WESTERN IOWA...SOUTHWEST INTO NORTHEASTERN
KANSAS AND ON INTO SOUTHEASTERN COLORADO. THE LOW LEVEL WIND FIELD
ACROSS OUR AREA REMAINS FROM THE NORTH AS A RESULT...BUT IS FAIRLY
LIGHT AT AROUND 5KTS. IN ADDITION TO THE AFOREMENTIONED MID TO
HIGH LEVEL CLOUDS BEGINNING TO WORK INTO THE REGION...SATELLITE
IMAGERY ALSO INDICATES A STRATUS DECK OVER MUCH OF THE NORTHERN
PLAINS...WITH THIS DECK MOVING SOUTH/SOUTHEAST AT AROUND 20KTS AND
ALREADY INFILTRATING PORTIONS OF CENTRAL NEBRASKA.
GUIDANCE FROM THE NAM...RAP...AND OPERATIONAL GFS ALL SUGGEST
ISENTROPIC UPGLIDE AND SATURATION...PRIMARILY ALONG THE 290-295K
SURFACES...WILL CONTINUE TO PROMOTE STRATUS OVER PORTIONS OF THE
REGION THROUGH MIDDAY. THERE IS SOME UNCERTAINTY AS TO HOW FAR
SOUTH THIS STRATUS DECK WILL MOVE ACROSS OUR CWA. THE OPERATIONAL
GFS REMAINS THE MOST AGGRESSIVE IN BRINGING THE DECK ACROSS OUR
ENTIRE CWA...WHILE THE NAM AND RAP BOTH SUGGEST THE NORTHERN HALF
OF OUR CWA WILL BE THE ONLY LOCATIONS TO OBSERVE THIS STRATUS.
SATELLITE IMAGERY INDICATES THE STRATUS DECK HAS SLOWED THROUGH
THE PAST 2-3 HOURS AND IT NOW SEEMS UNLIKELY THIS STRATUS WILL
MAKE IT TO OUR KANSAS COUNTIES BY 12Z...WHICH IS WHAT THE
OPERATIONAL GFS SUGGESTS. GIVEN THIS...OPTED TO PLAY CLOSER TO NAM
AND RAP GUIDANCE BY KEEPING THE FORECAST STRATUS PRIMARILY OVER
THE NORTHERN HALF OF THE CWA. GUIDANCE FROM THE NAM AND RAP ALSO
SUGGEST THE LOW LEVEL BAROCLINIC ZONE TO OUR SOUTH/SOUTHEAST WILL
LIFT NORTH AS A WARM FRONT TODAY...THUS CARRYING THE PRIMARY AXIS
OF ISENTROPIC UPGLIDE FARTHER NORTH WHICH SHOULD HELP CLEAR THE
STRATUS FROM MUCH OF OUR CWA BY MIDDAY. ALTHOUGH THE INCREASING
MID AND HIGH LEVEL CLOUDS MAY KEEP TEMPERATURES FROM MEETING THEIR
FULL DIURNAL POTENTIAL TODAY...THERE SHOULD BE ENOUGH DIABATIC
HEATING FOR 20-25 DEGREE TEMPERATURE RISES WHICH SHOULD PRESENT
AFTERNOON HIGHS GENERALLY IN THE 60S AND 70S...WITH THE ONLY
EXCEPTION BEING ACROSS OUR FAR NORTH WHERE THE STRATUS MAY KEEP
TEMPERATURES IN THE 50S.
THE BIG WEATHER STORY CONTINUES TO REVOLVE AROUND THE INCOMING
SYSTEM FOR THIS WEEKEND. GUIDANCE CONTINUES TO SUGGEST THE MID
LEVEL LOW...CURRENTLY OVER THE NORTHWESTERN CONUS...WILL OPEN UP
INTO A WAVE AND MOVE EAST INTO THE CENTRAL CONUS TONIGHT THROUGH
SUNDAY. AS THE MID LEVEL TROUGH APPROACHES FROM THE
WEST...RESULTANT SURFACE CYCLOGENESIS IS EXPECTED TO COMMENCE OVER
THE HIGH PLAINS OF NORTHEASTERN COLORADO OVERNIGHT TONIGHT. THIS
SURFACE LOW IS THEN EXPECTED TO QUICKLY EJECT NORTHEAST ACROSS THE
CENTRAL PLAINS AS THE MID LEVEL TROUGH AXIS APPROACHES OUR AREA
FROM THE WEST. AS THE SURFACE LOW MOVE NORTHEAST...AN ASSOCIATED
COLD FRONT IS EXPECTED TO SWEEP ACROSS OUR AREA SATURDAY AFTERNOON
INTO SATURDAY NIGHT.
QPF FIELDS FROM THE NAM...OPERATIONAL GFS...EC AND SREF-MEAN ALL
SUGGEST MID LEVEL THERMAL ADVECTION AHEAD OF THE MID LEVEL TROUGH
AXIS...WORKING IN CONCERT WITH LOW LEVEL CONVERGENCE ALONG THE LOW
LEVEL BAROCLINIC ZONE...WILL PROVIDE SUFFICIENT LIFT FOR
CONVECTIVE INITIATION NEAR THE BAROCLINIC ZONE SATURDAY AFTERNOON.
AT THIS TIME IT APPEARS THIS CONVECTION WILL INITIALIZE IN THE
VICINITY OF A LINE EXTENDING FROM FULLERTON...TO GRAND ISLAND...TO
PHILLIPSBURG. INCREASED VALUES OF LOW LEVEL MOISTURE AHEAD OF THE
LOW LEVEL BAROCLINIC ZONE...ALONG WITH INCREASING MID LEVEL LAPSE
RATES WITH THE APPROACH OF THE MID LEVEL TROUGH AXIS...SHOULD BE
SUFFICIENT ENOUGH TO PROVIDE 0-1MLCAPE VALUES ON THE ORDER OF
1000J/KG PER THE NAM AND OPERATIONAL GFS. IN ADDITION TO THE
POTENTIAL INSTABILITY...INCREASING MID AND UPPER LEVEL JET ENERGY
WILL ALSO LIKELY PROVIDE DEEP LAYER BULK SHEAR VALUES IN EXCESS
50KTS ACROSS MUCH OF THE REGION. ALSO...FORECAST PROXIMITY
SOUNDINGS FROM ACROSS THE CWA...PER THE NAM...SUGGEST A VEERING
LOW LEVEL WIND PROFILE FOR LOCATIONS STILL AHEAD OF THE LOW LEVEL
BAROCLINIC ZONE...WITH THE NAM ALSO SUGGESTING 0-1KM SRH WILL
APPROACH 300M^2/S^2 ACROSS EAST/SOUTHEASTERN PORTIONS OF OUR CWA.
NOW...INCREASING MID AND HIGH LEVEL CLOUDS WILL LIKELY KEEP
DIABATIC HEATING DOWN A TOUCH THROUGH MUCH OF THE DAY WHICH WILL
HELP SUSTAIN SOMETHING OF A CAPPING INVERSION...WHICH MEANS
INITIAL CONVECTIVE DEVELOPMENT COULD BE IN THE FORM OF A FEW
DISCRETE CELLS IN THE VICINITY OF THE LOW LEVEL BAROCLINIC ZONE.
GIVEN THE VERY STRONG DEEP LAYER BULK SHEAR...SUPER CELL
DEVELOPMENT WILL BE MORE THAN POSSIBLE AND GIVEN THIS...WILL
CONTINUE OUTLOOKING LARGE HAIL IN THE HWO. ADDITIONAL CONVECTIVE
DEVELOPMENT ALONG THE BAROCLINIC ZONE COULD THEN POTENTIALLY
EVOLVE INTO A QLCS WITH STRONG OUTFLOW WINDS AT THE SURFACE
REMAINING VERY POSSIBLE. WILL CONTINUE TO CARRY SEVERE
THUNDERSTORM WIND WORDING IN HWO AS WELL. FINALLY...GIVEN THE LOW
LEVEL SHEAR AS INDICATED BY THE NAM...WILL ALSO GO AHEAD AND
MENTION ISOLATED TORNADIC DEVELOPMENT IN ASSOCIATION WITH THE
INITIAL CONVECTION DURING THE LATE AFTERNOON HOURS.
STRONG WINDS WILL NOT ONLY BE A THREAT WITH AFTERNOON AND EVENING
THUNDERSTORM ACTIVITY ON SATURDAY...BUT STRONG SYNOPTIC WINDS WILL
ALSO BE OBSERVED ACROSS MUCH OF THE CWA SATURDAY. AS SURFACE
CYCLOGENESIS CONTINUES ACROSS THE HIGH PLAINS SATURDAY...THE LOW
LEVEL PRESSURE GRADIENT IS EXPECTED TO INTENSIFY GREATLY HEADING
INTO SATURDAY AFTERNOON...ESPECIALLY ACROSS THE SOUTHEASTERN ONE-
HALF OF THE CWA. IN ADDITION...FORECAST PROXIMITY SOUNDINGS FROM
ACROSS OUR CWA PER THE NAM AND OPERATIONAL GFS SUGGEST BOUNDARY
LAYER MIXING TO BETWEEN 850MB AND 800MB WILL BE REALIZED...WHICH
IS WHERE ~50KT WINDS WILL BE WAITING FOR TRANSPORT TO THE SURFACE.
INTERESTING TO NOTE THAT BOTH MET AND MAV GUIDANCE SUGGEST
PORTIONS OF OUR CWA WILL HIT WIND ADVISORY CRITERIA AT SOME POINT
DURING THE DAY SATURDAY...WITH MAV GUIDANCE SUGGESTING OUR
SOUTHWEST WILL HIT BETWEEN 18Z AND 21Z...AND THE NAM SUGGESTING
OUR SOUTHEAST WILL HIT CLOSER TO 00Z. RATHER THAN BLANKET A
MAJORITY OF OUR CWA WITH WIND ADVISORY WINDS...OPTED TO KEEP WINDS
JUST UNDER WIND ADVISORY ACROSS THE SOUTHEASTERN HALF OF THE CWA
WITH THE HOPES THAT WE WILL BE ABLE TO FINE-TUNE THE WIND FORECAST
AND INCREASE WINDS SOMEWHAT...INTO WIND ADVISORY CRITERIA...FOR
PORTIONS OF THE CWA ONCE THAT FORECAST BECOMES MORE CLEAR. WILL GO
AHEAD AND CONTINUE TO CARRY STRONG SYNOPTIC WIND WORDING IN THE
HWO FOR SATURDAY AFTERNOON. STRONG SYNOPTIC WINDS WILL NOT ONLY BE
A THREAT SATURDAY AFTERNOON...BUT WILL ALSO BE POSSIBLE SATURDAY
NIGHT INTO EARLY SUNDAY MORNING AFTER THE LOW LEVEL BAROCLINIC
ZONE CLEAR THE AREA. INTENSE LOW LEVEL PRESSURE RISES POST-FROPA
WILL PROMOTE YET ANOTHER INCREASE IN THE LOW LEVEL PRESSURE
GRADIENT ACROSS THE CWA 00Z-12Z SUNDAY...WITH GUIDANCE SUGGESTING
~20KT SUSTAINED WINDS WILL BE REALIZED ACROSS MUCH OF THE AREA.
WILL GO AHEAD AND CONTINUE CARRYING STRONG SYNOPTIC WIND WORDING
IN THE HWO FOR SATURDAY NIGHT/SUNDAY MORNING AS A RESULT.
WITH THE INFILTRATION OF A MUCH COLDER LOW LEVEL
AIRMASS...FORECAST PROXIMITY SOUNDINGS FROM THE ACROSS THE CWA PER
THE NAM...OPERATIONAL GFS AND EC ALL SUGGEST THE LOWER TROPOSPHERE
WILL BECOME SUPPORTIVE FOR SNOW ACROSS MUCH OF THE CWA SATURDAY
NIGHT INTO SUNDAY MORNING. AT THIS TIME IT APPEARS ANY
PRECIPITATION BEHIND THE LOW LEVEL BAROCLINIC WILL REMAIN FAIRLY
LIGHT ACROSS OUR CWA...THUS ANY SNOWFALL ACCUMULATIONS ACROSS OUR
CWA SHOULD REMAIN UNDER AN INCH. LOCATIONS WEST OF HIGHWAY 281 AND
NORTH OF I-80...WHICH IS WHERE THE LOW LEVEL COLD AIR ADVECTION
WILL BE FIRST TO INFILTRATE...SEEM MOST LIKELY TO OBSERVE THE MOST
SNOWFALL ACCUMULATION. IT IS WORTH NOTING THAT A FEW FORECAST
PROXIMITY SOUNDINGS SUGGEST A BRIEF PERIOD OF SLEET NEAR THE TRI-
CITIES AREA AS THE TRANSITION FROM RAIN TO SNOW BEGINS...BUT GIVEN
THE UNCERTAINTY AND BREVITY OF ANY SUCH POTENTIAL ACTIVITY...OPTED
TO HOLD OFF FROM MENTIONING THIS IN THE FORECAST FOR THE TIME
BEING.
FINALLY...TEMPERATURES LOOK TO FALL OFF DRAMATICALLY POST-FROPA
HEADING INTO SATURDAY NIGHT...AND WITH CONTINUED LOW LEVEL COLD
AIR ADVECTION AND LINGERING CLOUD COVER DURING THE DAY
SUNDAY...ITS DOUBTFUL TEMPERATURES WILL GO MUCH OF ANYWHERE DURING
THE DAY SUNDAY. LOWS IN THE MID 20S TO MID 30S ARE CURRENTLY
FORECAST FOR SATURDAY NIGHT...WITH TEMPERATURES STRUGGLING THROUGH
THE 30S DURING THE DAY SUNDAY. THE PASSAGE OF THE SURFACE RIDGE
AND THE INTRODUCTION OF LOW LEVEL RETURN FLOW SHOULD THEN PRESENT
A WARMING TREND TO FINISH OUT THE SHORT TERM FORECAST PERIOD.
FIRE WEATHER...A LOW LEVEL BAROCLINIC ZONE IS EXPECTED TO CLEAR
WESTERN PORTIONS OF OUR CWA BY LATE MORNING OR MIDDAY SATURDAY.
ALTHOUGH LOW LEVEL COLD AIR ADVECTION WILL BEGIN PUSHING INTO THE
AREA SHORTLY AFTER FROPA...THERE WILL BE A BRIEF PERIOD IN WHICH
LOW LEVEL DRY AIR ADVECTION WILL OUTWEIGH THE COLD AIR
ADVECTION...THUS ALLOWING LOW LEVEL RELATIVE HUMIDITY TO PLUMMET
AS WE HEAD INTO THE AFTERNOON HOURS SATURDAY. AT THIS TIME IT
APPEARS LOCATIONS GENERALLY WEST OF HIGHWAY 281 AND SOUTH OF I-80
WILL OBSERVE THE LOWEST RELATIVE HUMIDITY VALUES...SOMEWHERE NEAR
25%. THESE LOW VALUES OF RELATIVE HUMIDITY...WORKING IN CONCERT
WITH A STRONG LOW LEVEL WIND FIELD...SUSTAINED WELL ABOVE 17KTS
AND GUSTS WELL ABOVE 22KTS...WILL PROVIDE AN ELEVATED FIRE WEATHER
DANGER SATURDAY AFTERNOON. AS A RESULT...WILL GO AHEAD AND PRESENT
ELEVATED FIRE WEATHER WORDING IN THE FWF AND HWO.
LONG TERM...MONDAY THROUGH THURSDAY
THE MAIN THEME: ANOMALOUS "MID-WINTER"LIKE COLD EASES WITH TEMPS
REBOUNDING TO NORMAL AS FAVORABLE PATTERN DELIVERS ANOTHER PCPN
EVENT NEXT THU NGT-FRI AND MORE IN THE OFFING AFTER THAT.
HAZARDS: NONE FORESEEN ATTM. HOWEVER OUR CURRENT MIN RH IS FCST
AROUND 25% NEXT WED. IF WINDS END UP BREEZIER THAN CURRENTLY
EXPECTED...CAN SEE THIS BEING A DAY OF ELEVATED FIRE DANGER.
BIG PICTURE: BELIEVE OVERALL PATTERN CONTINUES TO SUGGEST MORE
RAIN IN OUR FUTURE...ESPECIALLY ALONG AND E OF HWY 281. THE NAO
WILL TRANSITION TO ITS POSITIVE PHASE NEXT WEEK WITH THE PNA
REMAINING NEGATIVE. THIS PHASE CONFIGURATION WILL BE SUPPORTIVE OF
AN ERN USA RIDGE/WRN USA TROF THRU MID-MONTH AND DELIVERS AT LEAST
TWO MORE FORESEEABLE CHANCES FOR PCPN. OVERALL...TEMPS WILL
AVERAGE NEAR NORMAL THRU NEXT THU.
QPF: THE NEXT DECENT OPPORTUNITY CONTS TO BE OUTLOOKED FOR NEXT
THU NGT-FRI /15TH-16TH/. MODELS ARE STRUGGLING WITH RUN-TO-RUN
CONSISTENCY ON HOW POTENT TO KEEP THE UPPER-LEVEL SYSTEM. THE 00Z
EC ENSEMBLE MEAN SHOWS SOME SPREAD AT THE BASE OF THE TROF. THIS
HAS IMPLICATIONS FOR PCPN AMTS. IF THE UPPER SYSTEM REMAINS
OPEN...IT WILL MOVE THRU FASTER WITH LESS OF AN OPPORTUNITY FOR
PCPN. WE`RE HOPING IT REMAINS CLOSED AS WE STRUGGLE TO EVEN
MAINTAIN NORMAL PCPN AMTS. ONCE THIS SYSTEM DEPARTS...WE GET
ANOTHER QUIET INTERLUDE NEXT WEEKEND. THEN WE LOOK TO THE 19TH-
20TH FOR THE NEXT TROF AND RAIN POTENTIAL.
THE DAILY DETAILS...
MON: THE UPPER TROF/CORE OF THE COLDEST AIR DEPARTS INTO THE MS
VALLEY...ALLOWING TEMPS TO EASE UPWARD. HIGH PRES AT THE SFC.
AFTER A BONE-CHILLING START WITH MOST PLACES IN THE TEENS...A NICE
BUT STILL CHILLY DAY.
TUE: LOW AMPLITUDE SHORTWAVE RIDGE WITH STRONG HIGH PRES OVER THE
ERN USA. THIS HIGH REMAINS PARKED THERE THRU THE REST OF THE WEEK
WITH A TENDENCY TO DRIFT TOWARD NEW ENGLAND. SUNNY. TEMPS RETURN
TO NEAR NORMAL /NOW ONLY IN THE LOWER 50S/.
WED: THE TRAILING END OF A WEAK COOL FRONT MOVES THRU LATE. THIS
MAY END UP MORE OF A WINDSHIFT LINE. ALL QG FORCING/MSTR WILL BE
FAR TO THE N. DRY WITH SEASONAL/NORMAL TEMPS. MORE BREEZY AS LEE
LOW DEVELOPS OVER CO...INTENSIFYING THE GRADIENT.
THU: NW FLOW/SHORTWAVE RIDGING AS PAC TROF MOVES INTO DESERT SW.
INCREASING CLOUDS AND BREEZY.
FRI: UPPER TROF EJECTS INTO SRN/CNTRL PLAINS. RAIN LOOKING
PROBABLE AND MAY BEGIN THU NGT. GFS ENSEMBLE PCPN PROBABILITIES
ARE HIGH WITH A 70% CHANCE FOR .10 IN 24 HRS WITH POTENTIAL FOR
MORE.
COOLER WITH TEMPS PROBABLY HELD DOWN IN THE 40S.
PREV DISCUSSION... /ISSUED 1135 PM CST THU NOV 8 2012/
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AVIATION/SHORT TERM/FIRE WEATHER....BRYANT
LONG TERM HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
445 AM CST FRI NOV 9 2012
.SHORT TERM...THROUGH 12Z MONDAY. OVERNIGHT UPPER AIR ANALYSIS
INDICATES LONG WAVE TROUGHING OVER THE WESTERN AND EASTERN
CONUS...AND A RIDGE PREVAILING OVER THE CENTRAL CONUS. A CLOSED
MID LEVEL LOW IS ALSO NOTED OVER THE NORTHWESTERN CONUS...WITH
ANOTHER CLOSED MID LEVEL CIRCULATION OVER THE NORTHEASTERN CONUS.
MID AND UPPER LEVEL JET ENERGY EXTENDS FROM CALIFORNIA...NORTHEAST
INTO THE NORTHERN PLAINS AND SOUTH CENTRAL CANADA...AND THEN
SOUTHEAST ACROSS THE OHIO VALLEY AND ON INTO THE SOUTHEASTERN
CONUS. TROPOSPHERIC FLOW IS NOT OVERLY STRONG NEAR OUR AREA AS A
RESULT...MAXING OUT AT AROUND 50KTS AT VARIOUS POINTS BETWEEN
500MB AND 200MB PER 00Z SOUNDING DATA FROM KLBF. WATER VAPOR
IMAGERY CLEARLY SHOWS THE CLOSED MID LEVEL LOWS OVER THE
NORTHWESTERN AND NORTHEASTERN CONUS. INCREASING VALUES OF MID
LEVEL MOISTURE ARE ALSO NOTED ON WATER VAPOR IMAGERY ADVECTING
NORTHEAST ALONG THE FRONT OF THE LONG WAVE TROUGH...INTO THE ROCKY
MOUNTAIN RANGE AND PLAINS. SOME OF THIS MID LEVEL MOISTURE IS
PROMOTING INCREASING MID TO HIGH LEVEL CLOUD COVER OVER PORTIONS
OF THE CENTRAL PLAINS. AT THE SURFACE A STATIONARY BOUNDARY IS
NOTED EXTENDING FROM WESTERN IOWA...SOUTHWEST INTO NORTHEASTERN
KANSAS AND ON INTO SOUTHEASTERN COLORADO. THE LOW LEVEL WIND FIELD
ACROSS OUR AREA REMAINS FROM THE NORTH AS A RESULT...BUT IS FAIRLY
LIGHT AT AROUND 5KTS. IN ADDITION TO THE AFOREMENTIONED MID TO
HIGH LEVEL CLOUDS BEGINNING TO WORK INTO THE REGION...SATELLITE
IMAGERY ALSO INDICATES A STRATUS DECK OVER MUCH OF THE NORTHERN
PLAINS...WITH THIS DECK MOVING SOUTH/SOUTHEAST AT AROUND 20KTS AND
ALREADY INFILTRATING PORTIONS OF CENTRAL NEBRASKA.
GUIDANCE FROM THE NAM...RAP...AND OPERATIONAL GFS ALL SUGGEST
ISENTROPIC UPGLIDE AND SATURATION...PRIMARILY ALONG THE 290-295K
SURFACES...WILL CONTINUE TO PROMOTE STRATUS OVER PORTIONS OF THE
REGION THROUGH MIDDAY. THERE IS SOME UNCERTAINTY AS TO HOW FAR
SOUTH THIS STRATUS DECK WILL MOVE ACROSS OUR CWA. THE OPERATIONAL
GFS REMAINS THE MOST AGGRESSIVE IN BRINGING THE DECK ACROSS OUR
ENTIRE CWA...WHILE THE NAM AND RAP BOTH SUGGEST THE NORTHERN HALF
OF OUR CWA WILL BE THE ONLY LOCATIONS TO OBSERVE THIS STRATUS.
SATELLITE IMAGERY INDICATES THE STRATUS DECK HAS SLOWED THROUGH
THE PAST 2-3 HOURS AND IT NOW SEEMS UNLIKELY THIS STRATUS WILL
MAKE IT TO OUR KANSAS COUNTIES BY 12Z...WHICH IS WHAT THE
OPERATIONAL GFS SUGGESTS. GIVEN THIS...OPTED TO PLAY CLOSER TO NAM
AND RAP GUIDANCE BY KEEPING THE FORECAST STRATUS PRIMARILY OVER
THE NORTHERN HALF OF THE CWA. GUIDANCE FROM THE NAM AND RAP ALSO
SUGGEST THE LOW LEVEL BAROCLINIC ZONE TO OUR SOUTH/SOUTHEAST WILL
LIFT NORTH AS A WARM FRONT TODAY...THUS CARRYING THE PRIMARY AXIS
OF ISENTROPIC UPGLIDE FARTHER NORTH WHICH SHOULD HELP CLEAR THE
STRATUS FROM MUCH OF OUR CWA BY MIDDAY. ALTHOUGH THE INCREASING
MID AND HIGH LEVEL CLOUDS MAY KEEP TEMPERATURES FROM MEETING THEIR
FULL DIURNAL POTENTIAL TODAY...THERE SHOULD BE ENOUGH DIABATIC
HEATING FOR 20-25 DEGREE TEMPERATURE RISES WHICH SHOULD PRESENT
AFTERNOON HIGHS GENERALLY IN THE 60S AND 70S...WITH THE ONLY
EXCEPTION BEING ACROSS OUR FAR NORTH WHERE THE STRATUS MAY KEEP
TEMPERATURES IN THE 50S.
THE BIG WEATHER STORY CONTINUES TO REVOLVE AROUND THE INCOMING
SYSTEM FOR THIS WEEKEND. GUIDANCE CONTINUES TO SUGGEST THE MID
LEVEL LOW...CURRENTLY OVER THE NORTHWESTERN CONUS...WILL OPEN UP
INTO A WAVE AND MOVE EAST INTO THE CENTRAL CONUS TONIGHT THROUGH
SUNDAY. AS THE MID LEVEL TROUGH APPROACHES FROM THE
WEST...RESULTANT SURFACE CYCLOGENESIS IS EXPECTED TO COMMENCE OVER
THE HIGH PLAINS OF NORTHEASTERN COLORADO OVERNIGHT TONIGHT. THIS
SURFACE LOW IS THEN EXPECTED TO QUICKLY EJECT NORTHEAST ACROSS THE
CENTRAL PLAINS AS THE MID LEVEL TROUGH AXIS APPROACHES OUR AREA
FROM THE WEST. AS THE SURFACE LOW MOVE NORTHEAST...AN ASSOCIATED
COLD FRONT IS EXPECTED TO SWEEP ACROSS OUR AREA SATURDAY AFTERNOON
INTO SATURDAY NIGHT.
QPF FIELDS FROM THE NAM...OPERATIONAL GFS...EC AND SREF-MEAN ALL
SUGGEST MID LEVEL THERMAL ADVECTION AHEAD OF THE MID LEVEL TROUGH
AXIS...WORKING IN CONCERT WITH LOW LEVEL CONVERGENCE ALONG THE LOW
LEVEL BAROCLINIC ZONE...WILL PROVIDE SUFFICIENT LIFT FOR
CONVECTIVE INITIATION NEAR THE BAROCLINIC ZONE SATURDAY AFTERNOON.
AT THIS TIME IT APPEARS THIS CONVECTION WILL INITIALIZE IN THE
VICINITY OF A LINE EXTENDING FROM FULLERTON...TO GRAND ISLAND...TO
PHILLIPSBURG. INCREASED VALUES OF LOW LEVEL MOISTURE AHEAD OF THE
LOW LEVEL BAROCLINIC ZONE...ALONG WITH INCREASING MID LEVEL LAPSE
RATES WITH THE APPROACH OF THE MID LEVEL TROUGH AXIS...SHOULD BE
SUFFICIENT ENOUGH TO PROVIDE 0-1MLCAPE VALUES ON THE ORDER OF
1000J/KG PER THE NAM AND OPERATIONAL GFS. IN ADDITION TO THE
POTENTIAL INSTABILITY...INCREASING MID AND UPPER LEVEL JET ENERGY
WILL ALSO LIKELY PROVIDE DEEP LAYER BULK SHEAR VALUES IN EXCESS
50KTS ACROSS MUCH OF THE REGION. ALSO...FORECAST PROXIMITY
SOUNDINGS FROM ACROSS THE CWA...PER THE NAM...SUGGEST A VEERING
LOW LEVEL WIND PROFILE FOR LOCATIONS STILL AHEAD OF THE LOW LEVEL
BAROCLINIC ZONE...WITH THE NAM ALSO SUGGESTING 0-1KM SRH WILL
APPROACH 300M^2/S^2 ACROSS EAST/SOUTHEASTERN PORTIONS OF OUR CWA.
NOW...INCREASING MID AND HIGH LEVEL CLOUDS WILL LIKELY KEEP
DIABATIC HEATING DOWN A TOUCH THROUGH MUCH OF THE DAY WHICH WILL
HELP SUSTAIN SOMETHING OF A CAPPING INVERSION...WHICH MEANS
INITIAL CONVECTIVE DEVELOPMENT COULD BE IN THE FORM OF A FEW
DISCRETE CELLS IN THE VICINITY OF THE LOW LEVEL BAROCLINIC ZONE.
GIVEN THE VERY STRONG DEEP LAYER BULK SHEAR...SUPER CELL
DEVELOPMENT WILL BE MORE THAN POSSIBLE AND GIVEN THIS...WILL
CONTINUE OUTLOOKING LARGE HAIL IN THE HWO. ADDITIONAL CONVECTIVE
DEVELOPMENT ALONG THE BAROCLINIC ZONE COULD THEN POTENTIALLY
EVOLVE INTO A QLCS WITH STRONG OUTFLOW WINDS AT THE SURFACE
REMAINING VERY POSSIBLE. WILL CONTINUE TO CARRY SEVERE
THUNDERSTORM WIND WORDING IN HWO AS WELL. FINALLY...GIVEN THE LOW
LEVEL SHEAR AS INDICATED BY THE NAM...WILL ALSO GO AHEAD AND
MENTION ISOLATED TORNADIC DEVELOPMENT IN ASSOCIATION WITH THE
INITIAL CONVECTION DURING THE LATE AFTERNOON HOURS.
STRONG WINDS WILL NOT ONLY BE A THREAT WITH AFTERNOON AND EVENING
THUNDERSTORM ACTIVITY ON SATURDAY...BUT STRONG SYNOPTIC WINDS WILL
ALSO BE OBSERVED ACROSS MUCH OF THE CWA SATURDAY. AS SURFACE
CYCLOGENESIS CONTINUES ACROSS THE HIGH PLAINS SATURDAY...THE LOW
LEVEL PRESSURE GRADIENT IS EXPECTED TO INTENSIFY GREATLY HEADING
INTO SATURDAY AFTERNOON...ESPECIALLY ACROSS THE SOUTHEASTERN ONE-
HALF OF THE CWA. IN ADDITION...FORECAST PROXIMITY SOUNDINGS FROM
ACROSS OUR CWA PER THE NAM AND OPERATIONAL GFS SUGGEST BOUNDARY
LAYER MIXING TO BETWEEN 850MB AND 800MB WILL BE REALIZED...WHICH
IS WHERE ~50KT WINDS WILL BE WAITING FOR TRANSPORT TO THE SURFACE.
INTERESTING TO NOTE THAT BOTH MET AND MAV GUIDANCE SUGGEST
PORTIONS OF OUR CWA WILL HIT WIND ADVISORY CRITERIA AT SOME POINT
DURING THE DAY SATURDAY...WITH MAV GUIDANCE SUGGESTING OUR
SOUTHWEST WILL HIT BETWEEN 18Z AND 21Z...AND THE NAM SUGGESTING
OUR SOUTHEAST WILL HIT CLOSER TO 00Z. RATHER THAN BLANKET A
MAJORITY OF OUR CWA WITH WIND ADVISORY WINDS...OPTED TO KEEP WINDS
JUST UNDER WIND ADVISORY ACROSS THE SOUTHEASTERN HALF OF THE CWA
WITH THE HOPES THAT WE WILL BE ABLE TO FINE-TUNE THE WIND FORECAST
AND INCREASE WINDS SOMEWHAT...INTO WIND ADVISORY CRITERIA...FOR
PORTIONS OF THE CWA ONCE THAT FORECAST BECOMES MORE CLEAR. WILL GO
AHEAD AND CONTINUE TO CARRY STRONG SYNOPTIC WIND WORDING IN THE
HWO FOR SATURDAY AFTERNOON. STRONG SYNOPTIC WINDS WILL NOT ONLY BE
A THREAT SATURDAY AFTERNOON...BUT WILL ALSO BE POSSIBLE SATURDAY
NIGHT INTO EARLY SUNDAY MORNING AFTER THE LOW LEVEL BAROCLINIC
ZONE CLEAR THE AREA. INTENSE LOW LEVEL PRESSURE RISES POST-FROPA
WILL PROMOTE YET ANOTHER INCREASE IN THE LOW LEVEL PRESSURE
GRADIENT ACROSS THE CWA 00Z-12Z SUNDAY...WITH GUIDANCE SUGGESTING
~20KT SUSTAINED WINDS WILL BE REALIZED ACROSS MUCH OF THE AREA.
WILL GO AHEAD AND CONTINUE CARRYING STRONG SYNOPTIC WIND WORDING
IN THE HWO FOR SATURDAY NIGHT/SUNDAY MORNING AS A RESULT.
WITH THE INFILTRATION OF A MUCH COLDER LOW LEVEL
AIRMASS...FORECAST PROXIMITY SOUNDINGS FROM THE ACROSS THE CWA PER
THE NAM...OPERATIONAL GFS AND EC ALL SUGGEST THE LOWER TROPOSPHERE
WILL BECOME SUPPORTIVE FOR SNOW ACROSS MUCH OF THE CWA SATURDAY
NIGHT INTO SUNDAY MORNING. AT THIS TIME IT APPEARS ANY
PRECIPITATION BEHIND THE LOW LEVEL BAROCLINIC WILL REMAIN FAIRLY
LIGHT ACROSS OUR CWA...THUS ANY SNOWFALL ACCUMULATIONS ACROSS OUR
CWA SHOULD REMAIN UNDER AN INCH. LOCATIONS WEST OF HIGHWAY 281 AND
NORTH OF I-80...WHICH IS WHERE THE LOW LEVEL COLD AIR ADVECTION
WILL BE FIRST TO INFILTRATE...SEEM MOST LIKELY TO OBSERVE THE MOST
SNOWFALL ACCUMULATION. IT IS WORTH NOTING THAT A FEW FORECAST
PROXIMITY SOUNDINGS SUGGEST A BRIEF PERIOD OF SLEET NEAR THE TRI-
CITIES AREA AS THE TRANSITION FROM RAIN TO SNOW BEGINS...BUT GIVEN
THE UNCERTAINTY AND BREVITY OF ANY SUCH POTENTIAL ACTIVITY...OPTED
TO HOLD OFF FROM MENTIONING THIS IN THE FORECAST FOR THE TIME
BEING.
FINALLY...TEMPERATURES LOOK TO FALL OFF DRAMATICALLY POST-FROPA
HEADING INTO SATURDAY NIGHT...AND WITH CONTINUED LOW LEVEL COLD
AIR ADVECTION AND LINGERING CLOUD COVER DURING THE DAY
SUNDAY...ITS DOUBTFUL TEMPERATURES WILL GO MUCH OF ANYWHERE DURING
THE DAY SUNDAY. LOWS IN THE MID 20S TO MID 30S ARE CURRENTLY
FORECAST FOR SATURDAY NIGHT...WITH TEMPERATURES STRUGGLING THROUGH
THE 30S DURING THE DAY SUNDAY. THE PASSAGE OF THE SURFACE RIDGE
AND THE INTRODUCTION OF LOW LEVEL RETURN FLOW SHOULD THEN PRESENT
A WARMING TREND TO FINISH OUT THE SHORT TERM FORECAST PERIOD.
.LONG TERM...MONDAY THROUGH THURSDAY
THE MAIN THEME: ANOMALOUS "MID-WINTER"LIKE COLD EASES WITH TEMPS
REBOUNDING TO NORMAL AS FAVORABLE PATTERN DELIVERS ANOTHER PCPN
EVENT NEXT THU NGT-FRI AND MORE IN THE OFFING AFTER THAT.
HAZARDS: NONE FORESEEN ATTM. HOWEVER OUR CURRENT MIN RH IS FCST
AROUND 25% NEXT WED. IF WINDS END UP BREEZIER THAN CURRENTLY
EXPECTED...CAN SEE THIS BEING A DAY OF ELEVATED FIRE DANGER.
BIG PICTURE: BELIEVE OVERALL PATTERN CONTINUES TO SUGGEST MORE
RAIN IN OUR FUTURE...ESPECIALLY ALONG AND E OF HWY 281. THE NAO
WILL TRANSITION TO ITS POSITIVE PHASE NEXT WEEK WITH THE PNA
REMAINING NEGATIVE. THIS PHASE CONFIGURATION WILL BE SUPPORTIVE OF
AN ERN USA RIDGE/WRN USA TROF THRU MID-MONTH AND DELIVERS AT LEAST
TWO MORE FORESEEABLE CHANCES FOR PCPN. OVERALL...TEMPS WILL
AVERAGE NEAR NORMAL THRU NEXT THU.
QPF: THE NEXT DECENT OPPORTUNITY CONTS TO BE OUTLOOKED FOR NEXT
THU NGT-FRI /15TH-16TH/. MODELS ARE STRUGGLING WITH RUN-TO-RUN
CONSISTENCY ON HOW POTENT TO KEEP THE UPPER-LEVEL SYSTEM. THE 00Z
EC ENSEMBLE MEAN SHOWS SOME SPREAD AT THE BASE OF THE TROF. THIS
HAS IMPLICATIONS FOR PCPN AMTS. IF THE UPPER SYSTEM REMAINS
OPEN...IT WILL MOVE THRU FASTER WITH LESS OF AN OPPORTUNITY FOR
PCPN. WE`RE HOPING IT REMAINS CLOSED AS WE STRUGGLE TO EVEN
MAINTAIN NORMAL PCPN AMTS. ONCE THIS SYSTEM DEPARTS...WE GET
ANOTHER QUIET INTERLUDE NEXT WEEKEND. THEN WE LOOK TO THE 19TH-
20TH FOR THE NEXT TROF AND RAIN POTENTIAL.
THE DAILY DETAILS...
MON: THE UPPER TROF/CORE OF THE COLDEST AIR DEPARTS INTO THE MS
VALLEY...ALLOWING TEMPS TO EASE UPWARD. HIGH PRES AT THE SFC.
AFTER A BONE-CHILLING START WITH MOST PLACES IN THE TEENS...A NICE
BUT STILL CHILLY DAY.
TUE: LOW AMPLITUDE SHORTWAVE RIDGE WITH STRONG HIGH PRES OVER THE
ERN USA. THIS HIGH REMAINS PARKED THERE THRU THE REST OF THE WEEK
WITH A TENDENCY TO DRIFT TOWARD NEW ENGLAND. SUNNY. TEMPS RETURN
TO NEAR NORMAL /NOW ONLY IN THE LOWER 50S/.
WED: THE TRAILING END OF A WEAK COOL FRONT MOVES THRU LATE. THIS
MAY END UP MORE OF A WINDSHIFT LINE. ALL QG FORCING/MSTR WILL BE
FAR TO THE N. DRY WITH SEASONAL/NORMAL TEMPS. MORE BREEZY AS LEE
LOW DEVELOPS OVER CO...INTENSIFYING THE GRADIENT.
THU: NW FLOW/SHORTWAVE RIDGING AS PAC TROF MOVES INTO DESERT SW.
INCREASING CLOUDS AND BREEZY.
FRI: UPPER TROF EJECTS INTO SRN/CNTRL PLAINS. RAIN LOOKING
PROBABLE AND MAY BEGIN THU NGT. GFS ENSEMBLE PCPN PROBABILITIES
ARE HIGH WITH A 70% CHANCE FOR .10 IN 24 HRS WITH POTENTIAL FOR
MORE.
COOLER WITH TEMPS PROBABLY HELD DOWN IN THE 40S.
&&
.PREV DISCUSSION... /ISSUED 1135 PM CST THU NOV 8 2012/
AVIATION...06Z KGRI TAF. VFR CONDITIONS TO CONTINUE THROUGH
10Z...WITH PREVAILING MVFR CONDITIONS THEN FORECAST 10Z-16Z.
PERIODIC IFR CONDITIONS WILL ALSO BE POSSIBLE 12Z-16Z. VFR
CONDITIONS ARE FORECAST 16Z ONWARD. SATELLITE IMAGERY INDICATES
STRATUS OVER SOUTH DAKOTA AND NORTHERN NEBRASKA...MOVING
SOUTH/SOUTHEAST AT AROUND 35KTS. AS OF 05Z THIS STRATUS HAD
REACHED POINTS AS FAR SOUTH AS KONL AND KANW AND IF THESE TRENDS
CONTINUE...STRATUS SHOULD INFILTRATE KGRI AROUND 10Z. PREVAILING
MVFR CONDITIONS HAVE BEEN INSERTED INTO THE TAF AS A RESULT. SOME
LOCATIONS WITHIN THIS STRATUS DECK HAVE ALSO REPORTED IFR
CEILINGS...THUS IS WHY PERIODIC IFR CONDITIONS HAVE ALSO BEEN
INSERTED. DIFFERENT SETS OF GUIDANCE OFFER DIFFERING SOLUTIONS AS
TO WHEN VFR CONDITIONS WILL BE RESTORED AT KGRI...BUT A BLEND OF
THIS GUIDANCE...WITH GREATER WEIGHT PLACED ON MAV/GFS GUIDANCE
WHICH HAS SEEMED TO HAVE A BETTER HANDLE ON THE EVOLVING SITUATION
THROUGH THE PAST 24 HOURS...WOULD SUGGEST MVFR CONDITIONS WILL
PREVAIL AT KGRI THROUGH MID TO LATE MORNING...WITH VFR CONDITIONS
EXPECTED THEREAFTER. THE SURFACE WIND WILL REMAIN GENERALLY LIGHT
AND VARIABLE THROUGH THE TAF PERIOD...WHICH MAY ALSO ALLOW FOR
PATCHY FOG DEVELOPMENT TONIGHT INTO FRIDAY MORNING. VISIBILITY
RESTRICTION...TO AROUND 5SM IN BR...HAS ALSO BEEN INSERTED INTO
THE TAF AS A RESULT.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM/AVIATION...BRYANT
LONG TERM...HALBLAUB
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
956 PM EST SAT NOV 10 2012
.SYNOPSIS...
A WARM FRONT WILL MOVE FROM SOUTHWEST TO NORTHEAST ACROSS OUR AREA
TONIGHT. THIS FRONT WILL BRING CLOUDS AND LIGHT PRECIPITATION TO
THE AREA...MAINLY AFTER MIDNIGHT. TEMPERATURES WILL BE SUCH THAT
LIGHT MIXED PRECIPITATION IS POSSIBLE...BUT NO ICE OR SNOW
ACCUMULATIONS ARE EXPECTED. THE WARM FRONT WILL BE NORTH OF THE
AREA ON SUNDAY AND A WARMING TREND IS EXPECTED WITH HIGH
TEMPERATURES BY MONDAY ABOUT 15 DEGREES ABOVE NORMAL.
&&
.NEAR TERM /UNTIL 7 AM SUNDAY MORNING/...
AS OF 956 PM EST SATURDAY...MODEST UPDATES TO SKY COVER AND POPS
THROUGH THE OVERNIGHT HOURS THROUGH MID-MORNING SUNDAY AS OF 930
PM TO ACCT FOR CURRENT TRENDS AND LATEST HRRR DATA. ALL AREAS HAVE
ESSENTIALLY TRENDED CLOUDY AND SHOULD REMAIN SO THROUGH THE
REMAINDER OF THE NIGHT AS WARM FRONT NOW APPROACHING QUICKLY FROM
THE WEST/SOUTHWEST. THUS MINIMUM TEMPERATURES HAVE BEEN REACHED IN
MOST LOCALES WITH STEADY OR SLOWLY RISING VALUES EXPECTED FROM
HERE ON OUT. BLOSSOMING ELEVATED CONVECTION ACROSS SW ONTARIO/LK
HURON INITIALIZED FAIRLY GOOD BY 21-00Z HRRR RUNS AND CORFIDI
VECTOR/STREAMLINE ANALYSIS SUGGESTS THIS ACTIVITY SHOULD STREAK
EAST...ALBEIT IN WEAKENED FORM INTO OUR NRN COUNTIES LATER TONIGHT
INTO TOMORROW MORNING. NO THUNDER AS ELEV INSTABILITY CURRENTLY
DRIVING GREAT LAKES ACTIVITY WILL ERODE BY THE TIME IT GETS HERE.
NONETHELESS HAVE RAISED POPS UPWARD BY 10/20% ACROSS NRN NY AND
LEAST BROUGHT CHC POPS INTO NRN VT ACCORDINGLY. QPF STILL TO
REMAIN LIGHT...BUT COULD SEE SLIGHTLY HIGHER AMTS TO NEAR
0.10-0.15 INCHES ACROSS NRN NY COUNTIES. P-TYPE MAINLY LIQUID AS
WARMER AIR ALOFT STREAMS QUICKLY NORTHEAST...THOUGH A BRIEF PERIOD
OF VERY LIGHT FZRA POSSIBLE ACROSS FAR NERN VT AFTER 08Z. HAVE A
GOOD NIGHT.
&&
.SHORT TERM /7 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
AS OF 334 PM EST SATURDAY...WE COULD SEE SOME LIGHT MIXED
PRECIPITATION OVER PARTS OF THE NORTHEAST KINGDOM EARLY SUNDAY
MORNING...BUT WARM FRONT QUICKLY LIFTS NORTH OF THE AREA AS UPPER
RIDGE BEGINS TO AMPLIFY OVER THE AREA. BY MIDDAY WE SHOULD SEE DRY
WEATHER AND PLENTY OF SUNSHINE WITH THE AREA IN THE WARM SECTOR.
TEMPERATURES SHOULD ALSO WARM INTO THE 50S MOST LOCATIONS.
PRESSURE GRADIENT WILL STRENGTHEN OVER AREA IN THE AFTERNOON...SO
LOOKING AT SOME GUSTS FROM THE SOUTH AND SOUTHWEST LATE IN THE
DAY...20 TO 30 MPH. PRESSURE GRADIENT STRENGTHENS EVEN MORE ON
MONDAY AS LARGE UPPER TROUGH MOVES TOWARD THE REGION. LOOKING AT
BREEZY TO WINDY CONDITIONS MONDAY AFTERNOON AND EVENING. WARMEST
AIR IN THE LOWER LEVELS MOVES INTO THE REGION WITH HIGHS IN THE
60S...BUT WITH THAT MUCH WIND...IT WILL NOT FEEL THAT WARM.
NEVERTHELESS...THESE TEMPERATURES ARE ABOUT 15 DEGREES ABOVE
NORMAL FOR THIS TIME OF YEAR. THE HIGHER AMPLITUDE UPPER PATTERN
SUGGESTS THAT PRECIPITATION WILL BE CLOSELY TIED TO THE UPPER
TROUGH AXIS AND SURFACE COLD FRONT. AS A RESULT...PRECIPITATION
WILL BE SLOW TO PUSH IN AND EXPECT A DRY DAY ON MONDAY AND INTO
THE FIRST PART OF MONDAY EVENING. RAIN SHOULD THEN SPREAD INTO THE
REGION LATER MONDAY NIGHT...ESPECIALLY AFTER MIDNIGHT. GOING
FORECAST HAS LIKELY TO CATEGORICAL PRECIPITATION CHANCES DURING
THAT TIME PERIOD AND HAVE KEPT THAT THE SAME.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 334 PM EST SATURDAY...THE MAIN WEATHER FEATURE OF INTEREST DURING
THE EXTENDED IS THE COLD FRONT FROM THE PREVIOUS PERIOD. THE
FRONT WILL CONTINUE PROGRESSING EASTWARD ACROSS THE NORTH COUNTRY
TUESDAY. THE PRESENCE OF A LARGE UPPER RIDGE AHEAD OF THE FRONT
AND POTENTIAL FOR NEARLY BOUNDARY-PARALLEL UPPER FLOW SUGGESTS THE
FRONT MAY BE SLOW TO MOVE EASTWARD. STRONG POST-FRONTAL 850/925 MB
COLD ADVECTION WITH 850 MB TEMPERATURES FALLING FROM 10C TO 0-2C
DURING THE AFTERNOON. WOULD EXPECT A NON-DIURNAL TEMPERATURE RANGE
ON TUESDAY WITH HIGHS IN THE 40S TO AROUND 50 LIKELY BEING REACHED
LATE MORNING/EARLY AFTERNOON. PRECIPITATION PROBABILITIES RANGE
FROM LIKELY AHEAD OF THE FRONT ON TUESDAY BEFORE TAPERING QUICKLY
WITH WESTWARD EXTENT. WHILE RAIN IS EXPECTED AHEAD OF THE
FRONT...ANY LIGHT PRECIPITATION THAT OCCURS BEHIND THE FRONT COULD
MIX TO SNOW SHOWERS IN THE NORTHERN ADIRONDACKS AS THERMAL
PROFILES COOL. THE FRONT COULD BE A LITTLE SLOW TO MOVE OUT OF
VERMONT ON TUESDAY NIGHT AS UPPER FLOW BECOMES MORE BOUNDARY-
PARALLEL...SO HAVE CARRIED SLIGHT CHANCE TO CHANCE PRECIPITATION
PROBABILITIES INTO TUESDAY NIGHT.
THE REST OF THE EXTENDED IS RATHER BENIGN AS SFC HIGH PRESSURE
BECOMES ESTABLISHED NORTH OF THE REGION. SEVERAL WEAK MID-LEVEL
SHORTWAVE TROUGHS TRAVERSE THE REGION LATE IN THE WEEK...THOUGH THE
TROUGHS WILL HAVE LIMITED MOISTURE TO WORK WITH. SO WHILE THE
TROUGHS MAY PRODUCE SOME CLOUDS HAVE KEPT THE FORECAST DRY. 850 MB
TEMPERATURES OF -3 TO -6C WEDNESDAY AND THURSDAY RESULT IN HIGHS IN
THE 40S AND LOWS IN THE 20S BOTH DAYS. MODERATING TEMPERATURES ARE
EXPECTED BY LATE WEEK AS 850MB TEMPERATURES RECOVER TO AROUND
0C.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
THROUGH 00Z MONDAY...VFR CONDITIONS EXPECTED THROUGH THE PERIOD. A
WARM FRONT WILL PASS ACROSS THE REGION TONIGHT AND SUNDAY MORNING
WITH INCREASING CLOUDS AND SOME VERY LIGHT PRECIPITATION.
HOWEVER...CEILINGS AND VISIBILITIES ARE EXPECTED TO REMAIN VFR AT
ALL TAF SITES. SOME PATCHES OF LIGHT PRECIPITATION ARE POSSIBLE
THIS EVENING...MAINLY IN THE FORM OF LIGHT RAIN OR
DRIZZLE...HOWEVER A BRIEF PERIOD OF VERY LIGHT FREEZING RAIN IS
POSSIBLE AT SLK/MPV BEFORE TEMPERATURES RISE OVERNIGHT. GREATEST
CHANCE OF PRECIPITATION WILL OCCUR AFTER 05Z AND INTO THE FIRST
PART OF SUNDAY MORNING. HOWEVER ASIDE FROM A POSSIBLE VERY BRIEF
PERIOD OF FREEZING RAIN AT SLK/MPV...IT WILL REMAIN LIGHT AND IN
THE FORM OF LIQUID RAIN. ANY REMAINING RAIN SHOWERS WILL COME TO
AN END AFTER 14Z SUNDAY MORNING WITH GENERALLY DRYING AND CLEARING
SKIES BY THE AFTERNOON. SOUTH WINDS WILL BE INCREASING LATER
TONIGHT AND INTO SUNDAY...WITH SOME GUSTS 15-25 KNOTS BY THE
AFTERNOON.
OUTLOOK 00Z MONDAY THROUGH THURSDAY...
00Z MONDAY THROUGH 00Z TUESDAY...VFR UNDER RIDGE OF HIGH PRESSURE.
GUSTY SOUTH WINDS LIKELY...ESPECIALLY MONDAY AFTERNOON. 00Z
TUESDAY THROUGH 00Z WEDNESDAY...PERIODS OF MVFR/IFR IN RAIN
SHOWERS AS A COLD FRONT MOVES ACROSS THE REGION. 00Z WEDNESDAY
ONWARD...VFR UNDER BUILDING HIGH PRESSURE.
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR MONDAY NOVEMBER 12TH:
BURLINGTON - 66 IN 1982
MONTPELIER - 62 IN 1982
ST. JOHNSBURY - 65 IN 1911
MASSENA - 70 IN 1982
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...JMG
SHORT TERM...EVENSON
LONG TERM...LOCONTO
AVIATION...MUCCILLI
CLIMATE...EVENSON
AREA FORECAST DISCUSSION
NWS BUFFALO NY
503 PM EST FRI NOV 9 2012
.SYNOPSIS...
A STRENGTHENING WARM FRONTAL BOUNDARY WILL EXTEND FROM THE UPPER
GREAT LAKES TO LAKE ERIE TONIGHT...THEN WILL SLOWLY LIFT TO THE
NORTH ACROSS OUR REGION DURING THE DAY SATURDAY. THIS WILL KEEP OUR
FORECAST AREA SHROUDED WITH CLOUDS WHILE EVENTUALLY PROMOTING SOME
SHOWER ACTIVITY. THE SILVER LINING TO THIS PROCESS WILL BE THE NEAR
RECORD WARMTH THAT WILL FOLLOW FOR SUNDAY AND MONDAY.
&&
.NEAR TERM /THROUGH SATURDAY NIGHT/...
SOME VERY ISOLATED LAKE EFFECT SHOWERS HAVE DEVELOPED EAST OF LAKE
ONTARIO IN A NARROW BAND ACROSS FAR NORTHERN OSWEGO COUNTY AT 4PM.
THERE IS JUST ENOUGH COOL AIR OVER THE EAST END OF THE LAKE FOR LAKE
INDUCED CAPE OF 100-200 J/KG. SOME ADDITIONAL WEAK LIFT IS PRESENT
WITH THE 850 MB WARM FRONT ORIENTED JUST TO THE WEST FROM TORONTO
SOUTHEAST TO ROCHESTER. UPDATED FORECAST GRIDS FOR THIS NARROW BAND
WHICH THE 19Z HRRR MODEL SHOWS WELL. ONCE THE 850MB FRONT SLIDES A
BIT FURTHER NORTH THIS EVENING THE WARM ADVECTION ALOFT WILL END
ANY LAKE INSTABILITY.
PREVIOUS DISCUSSION...
THE NEXT 24 HOURS WILL BE A TRANSITION PERIOD BETWEEN THE EXTENSIVE
STRETCH OF CHILLY WEATHER THAT WE HAVE EXPERIENCED FOR THE PAST TWO
WEEKS...AND A WELCOMED BATCH OF ANOMALOUS WARMTH THAT WILL CARRY US
INTO THE START OF THE NEW WORK WEEK. MORE ON THIS IN A MOMENT.
MID AND UPPER LEVEL RIDGING WILL BE FOUND OVER THE REGION TONIGHT
WHILE A VERY WEAK SURFACE BOUNDARY WILL SAG SOUTH FROM SOUTHERN
ONTARIO. THIS BOUNDARY WILL STALL OVER THE VCNTY OF THE PENNSYLVANIA
BORDER DURING THE WEE HOURS OF THE MORNING BEFORE LIFTING BACK TO
THE NORTH ON SATURDAY IN THE FORM OF A WARM FRONT. WHILE THERE WILL
BE VERY LITTLE LIFT ASSOCIATED WITH THE PASSAGE OF THIS BOUNDARY...
WE WILL CONTINUE TO BE SHROUDED UNDER A WEALTH OF CLOUD COVER.
SAT IMAGERY SHOWS EXTENSIVE MID LEVEL MOISTURE (ALTO-CU) STREAMING
EASTWARD ACROSS ALL OF THE GREAT LAKES REGION. THIS MOIST FLOW WILL
CONTINUE THROUGH TONIGHT...ENSURING US OF KEEPING OUR MAINLY CLOUDY
SKIES. THE CLOUD COVER WILL KEEP OUR OVERNIGHT TEMPERATURES A FEW
DEGREES HIGHER THAN THOSE OF LAST NIGHT...WITH LOWS GENERALLY
RANGING FROM THE LOWER 30S EAST OF LK ONTARIO TO THE MID AND UPPER
30S OVER THE WESTERN COUNTIES.
AS WE PROGRESS THROUGH THE PRE DAWN HOURS...THE AFOREMENTIONED
FRONTAL BOUNDARY WILL START TO LIFT BACK TO THE NORTH. THE
ASSOCIATED ISENTROPIC LIFT SHOULD BE STRONG TO HELP GENERATE SOME
SHOWERS OVER THE SOUTHWEST CORNER OF THE STATE BEFORE DAYBREAK...
WITH THE SHOWERS GRADUALLY LIFTING NORTH ACROSS WESTERN NEW YORK
BETWEEN DAYBREAK AND LUNCHTIME ON SATURDAY.
DURING THE COURSE OF SATURDAY AFTERNOON...THE WARM FRONT WILL
CONTINUE ITS NORTHEASTWARD TREK BY MOVING FROM THE FINGER LAKES TO
THE EASTERN LAKE ONTARIO REGION....WHERE ANY ASSOCIATED LIGHT
SHOWERS WILL BE FOCUSED. WILL USE CHC POPS FOR THE BULK OF THE
REGION WITH THE EXCEPTION OF THE SRN TIER WHERE LIKELY POPS WILL BE
USED EARLY IN THE MORNING.
THE CLOUDS SHOULD THIN OUT ACROSS THE SRN TIER IN THE WAKE OF THE
FRONT DURING THE MID AND LATE AFTERNOON...AND BEING IN THE WARM
SECTOR...THIS AREA SHOULD BE ABLE TO EXPERIENCE HIGH TEMPERATURES IN
THE LOW TO MID 50S. MERCURY READINGS WILL SOME 10 DEG F LOWER ACROSS
THE NORTH COUNTRY.
SPEAKING OF TEMPS...READINGS ACROSS OUR FORECAST AREA HAVE AVERAGED
OVER 5 DEG F BELOW NORMAL DURING THE PAST TWO WEEKS. THIS TREND WILL
END TODAY. AS WE PROGRESS THROUGH THE END OF THE WEEKEND INTO EARLY
NEXT WEEK...TEMPS BEHIND THE WARM FRONT WILL BE AS MUCH AS 20
DEGREES F ABOVE NORMAL.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
THE NORTHWARD PASSAGE OF THE WARM FRONT ON SATURDAY NIGHT WILL ALSO
LIFT AND SHIFT ANY REMAINING PRECIP TO THE NORTH AND EAST. WILL
CARRY CHANCE POPS FOR THE NORTH COUNTRY AND THE SAINT LAWRENCE RIVER
FOR THE EVENING AND EARLY NIGHT...THEN UPPER AND MID LEVEL RIDGING
WILL SUPPRESS PRECIP ACROSS THE REST OF THE REGION. OVERNIGHT TEMPS
WILL SLIP ONLY A FEW DEGREES TO EARLY LOWS IN THE 40S...THEN CLIMB
SLOWLY OVERNIGHT TO THE MID TO UPPER 40S ALONG THE LAKE PLAINS AND
LOWER TO MID 40S ELSEWHERE.
THE WARM AIR WILL COVER THE REGION ON SUNDAY WITH TEMPERATURES CLOSE
TO RECORD HIGHS. THE RECORD HIGH TEMPERATURE OF 68 DEGREES IN
BUFFALO MAY BE TIED OR BROKEN...BUT ROCHESTER`S RECORD HIGH OF 73
MAY BE TOUGHER TO REACH. SUNNY SKIES WILL PREVAIL WITH A SOUTHERLY
BREEZE.
A COLD FRONT WILL APPROACH ON MONDAY WITH A DEEP MERIDIONAL
PATTERN...THE FRONT REACHING FROM LOW PRESSURE LIFTING NORTH FROM
THE WESTERN GREAT LAKES ALL THE WAY SOUTH TO THE GULF OF MEXICO.
SOUTHERLY WINDS WILL BE ON THE INCREASE AHEAD OF THE FRONT RANGING
15 TO 25 MPH AND GUSTING OVER 30 MPH. IT APPEARS THAT WE WILL NOT
REACH WIND ADVISORY CONDITIONS ON MONDAY...BUT IT IS WORTH CONTINUED
SCRUTINY.
THE COLD FRONT AND ASSOCIATED PRECIP WILL CROSS THE REGION MONDAY
NIGHT. THERE IS THE POSSIBILITY OF THUNDER ALONG THE FRONT AS BOTH
GFS AND ECMWF ARE SHOWING 850MB SOUTHERLY JET OF 50-60KT...WILL HOLD
ON INTRODUCING THUNDER ON THIS FORECAST SET UNTIL THE PATTERN
BECOMES MORE CERTAIN.
SUNDAY NIGHT WILL COOL TO OVERNIGHT LOW TEMPS IN THE LOWER 50S TO
UPPER 40S...THEN PREFRONTAL WARMING WILL RAISE TEMPS BACK TO THE
LOWER TO MID 60S ON MONDAY. NOT AS WARM AS SUNDAY AS THE CLOUDS WILL
THICKEN AHEAD OF THE APPROACHING FRONT. LOWS MONDAY NIGHT WILL BE
OCCUR FOLLOWING THE FRONTAL PASSAGE...FALLING TO THE UPPER 30S TO
LOW 40S ACROSS THE WESTERN COUNTIES AND TO THE MID TO UPPER 40S FOR
CENTRAL AND NORTHERN NEW YORK.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
THE COLD FRONT WILL CONTINUE ACROSS THE REGION ON TUESDAY WITH MUCH
COLDER AIR TO FOLLOW. THE BULK OF THE RAIN WILL BE ALONG OR PAST THE
EASTERN EDGE OF THE FORECAST AREA. THE TIMING OF THE FRONTAL PASSAGE
IS SIMILAR ON GFS AND ECMWF AS ARE THE PLACEMENT AND TRACK OF THE
TRAILING UPPER TROUGH AND THE BOUNDARY LAYER THERMAL PATTERN AND
COOLING. WILL EXPECT 850MB TEMPS OF -6C TO -8C DURING MUCH OF
TUESDAY AND ABOUT 6KFT TO 8KFT DEPTH TO THE UNSTABLE BOUNDARY
LAYER...THUS SOME LAKE RESPONSE IS EXPECTED. WILL HAVE SCATTERED
LAKE EFFECT SNOW SHOWERS TO THE EAST OF THE LAKES DURING
TUESDAY...TRANSITIONING TO A GEORGIAN BAY TO LAKE ONTARIO CONNECTION
ON MORE NORTHWESTERLY FLOW DURING TUESDAY NIGHT. THE SHALLOW DEPTH
OF THE UNSTABLE LAYER AND DRY AIR ALOFT SHOULD SUBSTANTIALLY LIMIT
THE AMOUNT OF LAKE EFFECT PRECIP...BUT SHOULD SEE ENOUGH FOR A
COATING TO AN INCH OR SO ACROSS THE TOP OF THE CHAUTAUQUA RIDGE AND
THE SOUTHERN TO WESTERN SLOPES OF THE TUG HILL AND SOUTHERN OSWEGO
COUNTY.
SURFACE HIGH PRESSURE OVERLAIN BY A ZONAL FLOW ALOFT FROM WEDNESDAY
THROUGH FRIDAY WILL BRING A PERIOD OF BENIGN AND DRY WEATHER WITH A
SLOW WARMING TREND. OVERNIGHT LOW TEMPS WILL BE IN THE MID 20S TO
LOW 30S EACH NIGHT WITH HIGHS ON WEDNESDAY IN THE MID 30S TO LOW 40S
CLIMBING TO THE LOWER TO MID 40S ON THURSDAY AND THE UPPER 40S TO
LOW 50S ON FRIDAY.
&&
.AVIATION /22Z FRIDAY THROUGH WEDNESDAY/...
MIX OF VFR AND MVFR CIGS ARE PRESENT ACROSS THE MAJORITY OF THE
REGION THIS EVENING AS A WEAK WARM FRONT IS POSITIONED JUST SOUTH OF
THE STATE. A VERY NARROW BAND OF LAKE EFFECT RAIN IS PRESENT EAST OF
LAKE ONTARIO SOUTH OF THE KART TERMINAL.
FOR TONIGHT...THE ALTO-CU DECK WILL REMAIN IN PLACE THROUGH
MIDNIGHT WITH CIGS GRADUALLY LOWERING OVERNIGHT. CIGS MAY DROP TO
MVFR LEVELS AGAIN AT KJHW AS LIGHT SHOWERS DEVELOP LATE IN THE VCNTY
OF A WARM FRONT. THE WEAK LAKE BAND SOUTH OF KART WILL FALL APART A
LITTLE LATER THIS EVENING WHEN MID LEVEL WARM AIR SPREADS OVER THE
LAKE.
SATURDAY THE SURFACE WARM FRONT WILL LIFT NORTH ACROSS THE STATE
THROUGH THE DAY WITH RAIN SHOWERS DEVELOPING ALONG AND AHEAD. MAINLY
LOW END VFR OR MVFR CIGS EXPECTED. SOME EARLY MORNING IFR CIGS COULD
DEVELOP AT KJHW WITH ANY SHOWERS BEFORE SUNRISE..
OUTLOOK...
SATURDAY NIGHT...MAINLY VFR WITH A CHANCE OF RAIN SHOWERS EAST OF
LAKE ONTARIO.
SUNDAY...VFR.
MONDAY...VFR DURING THE DAY THEN VFR/MVFR IN RAIN WITH FRONTAL
PASSAGE MON NIGHT.
TUESDAY...MVFR IN SCTD SNOW SHOWERS.
&&
.MARINE...
A WEAK FRONTAL BOUNDARY JUST NORTH OF LAKE ONTARIO THIS EVENING WILL
GRADUALLY DROP SOUTH ACROSS WESTERN NEW YORK DURING THE OVERNIGHT.
THIS WILL ALLOW MODERATE WEST TO SOUTHWEST BREEZES EARLY TONIGHT TO
BECOME LIGHT AND VARIABLE BEFORE FRESHENING FROM THE EAST LATE
TONIGHT AND SATURDAY. WHILE WINDS AND WAVES WILL BE CLOSE TO SCA
CRITERIA FROM SODUS BAY TO MEXICO BAY THIS EVENING...CONDITIONS
THROUGH SATURDAY SHOULD NOT WARRANT ANY MARINE FLAGS.
WINDS WILL VEER TO A SOUTHERLY COMPONENT IN THE WAKE OF A WARM FRONT
DURING THE SECOND HALF OF THE WEEKEND...FIRST OVER LAKE ERIE AND
EVENTUALLY OVER LAKE ONTARIO. AS THESE WINDS INCREASE LATE SUNDAY
NIGHT AND MONDAY...SCA WILL LIKELY BE NEEDED.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...RSH
NEAR TERM...RSH/SMITH
SHORT TERM...WCH
LONG TERM...WCH
AVIATION...RSH/SMITH
MARINE...RSH
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
958 PM EST SAT NOV 10 2012
.SYNOPSIS...
LOW PRESSURE OVER THE PLAINS TODAY WILL MOVE NORTH INTO CANADA ON
SUNDAY AND PUSH A STRONG COLD FRONT ACROSS THE REGION ON MONDAY.
HIGH PRESSURE WILL DOMINATE THE WEATHER ACROSS THE REGION TUESDAY
THROUGH THE END OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
SOUTHERLY FLOW WILL STAY UP TONIGHT. WARM FRONT IS SITTING ACROSS
LAKE ERIE BUT WILL PUSH NORTH EVEN MORE OVERNIGHT. TEMPERATURES
HAVING A HARD TIME FALLING AND HAVE ADJUSTED OVERNIGHT LOWS UP
SOME. CONTINUING TO GET LEFTOVER DEBRIS/CIRRUS CLOUD COVER OFF AND
ON...SO A MIX OF PARTLY CLOUDY AND MOSTLY CLEARS WILL WORK.
HIGH PRESSURE WILL DRIFT OFF THE NEW ENGLAND COAST TONIGHT AS LOW
PRESSURE DEEPENS OVER THE NORTHERN PLAINS.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY NIGHT/...
THE SOUTHERLY WINDS WILL INCREASE ON SUNDAY WITH A BREEZY TO WINDY
AFTERNOON ANTICIPATED. IF HIGH LEVEL CLOUDINESS REMAINS THIN
ENOUGH MOST LOCATIONS WILL WARM WELL INTO THE 60S WITH SOME 70S
LIKELY. A FEW LOCATIONS WILL APPROACH RECORD LEVELS.
RECORD HIGHS FOR SUNDAY...
TOLEDO 73 IN 1927
FINDLAY 72 IN 1964
MANSFIELD 70 IN 1927
CLEVELAND 73 IN 1915
AKRON/CANTON 72 IN 1915
YOUNGSTOWN 70 IN 1939
ERIE 73 IN 1915
THE WARM TEMPERATURES WILL CONTINUE INTO MONDAY NIGHT WITH THE
SOUTHERLY WINDS AND INCREASING CLOUD COVER. EXPECT TO SEE ALL
LOCATIONS REMAIN IN THE 50S. IF CLOUDS THICKEN AND LOWER FAST
ENOUGH WE MAY SEE A FEW LOCATIONS REMAIN NEAR 60 FOR LOWS.
A STRONG COLD FRONT WILL MOVE INTO THE REGION ON MONDAY WITH RAIN
GRADUALLY SPREADING ACROSS THE AREA FROM WEST TO EAST. AS THE
FRONT PASSES IT WILL FEEL SIGNIFICANTLY COOLER BY THE AFTERNOON.
TEMPERATURES SHOULD ACTUALLY DROP BACK INTO THE 40S IN THE WAKE OF
THE FRONT. THE MAIN SHIELD OF RAIN SHOULD PUSH EAST OF THE REGION
BY MONDAY EVENING. THERE WILL THEN LIKELY BE SOME LAKE EFFECT
SHOWERS/SNOW THAT DEVELOP DOWNWIND OF LAKE ERIE BY TUESDAY
MORNING. THESE WILL MAINLY OCCUR FROM ASHTABULA COUNTY INTO NW PA.
THE SNOW SHOULD BE LIMITED TO INLAND ERIE COUNTY INTO CRAWFORD
COUNTY. DEFINITELY CAN NOT RULE OUT SOME LIGHT ACCUMULATIONS AT
THIS POINT. OTHERWISE IT WILL BE MUCH COOLER ON TUESDAY WITH HIGHS
NOT GETTING OUT OF THE 30S ACROSS THE EASTERN HALF OF THE REGION.
THERE MAY BE A FEW LOWER 40S ACROSS THE WEST WHERE THE SUNSHINE
SHOULD OCCUR.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
HIGH PRESSURE LOOKS TO SET UP JUST NE OF THE LAKES FOR LATE WED INTO
SAT TO PRODUCE DRY CONDITIONS WED AND THU. BY FRI AND SAT THE MODELS
BRING AN UPPER TROUGH INTO THE OH VALLEY. TIMING IS DIFFERENT ON THE
MODELS AND EACH MODEL RUN CONTINUES TO DIFFER SO OVERALL CONFIDENCE
IS LOW AT THIS POINT FOR FRI AND SAT. WITH UPPER TROUGH LIKELY TO BE
OVER OR NEAR THE AREA WILL OPT FOR MORE CLOUDINESS FRI AND SAT AND
UP POPS TO SLIGHT CHANCE.
TEMPS SHOULD SHOW A GRADUAL WARMING TREND WED INTO SAT OF A DEGREE
OR TWO EACH DAY.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
LOOKING AT WINDS AND TEMPS...BEST FIT FOR WARM FRONT PLACEMENT
TAKES IT FROM CENTRAL LWR MI ESE ACROSS LAKE ERIE INTO NERN OHIO.
WINDS AT KERI ARE FRONT 060 DEGREES AND KCLE AND KYNG HAVE BACKED
10 TO 30 DEGREES OVER THE PAST COUPLE HOURS SO FRONT MAY BE
WAFFLING A BIT INTO THE AREA. A QUICK LOOK AT THE HRRR HIGH REZ
WIND FORECAST SUGGESTS THIS STOPS AND REVERSES OVER THE NEXT
COUPLE HOURS TURNING WINDS AT KERI BACK TO SOUTHERLY. HAVE ALSO
SEEN DEVELOPMENT OF A CIG AROUND 45 HUNDRED FEET AT KERI AND
SATELLITE SHOWS A SIMILAR DECK DEVELOPING IN VICINITY OF KCLE AS
WELL. WILL CARRY THIS FOR THE NEXT FEW HOURS BUT WITH THE WARM
FRONT BEGINNING TO MOVE NORTH AGAIN WILL NOT CARRY THROUGH THE
NIGHT. OTHER THAN THAT EXPECT ONLY CONVECTIVE DEBRIS CLOUDS
100-120 FEET TO AFFECT TERMINALS OVERNIGHT. SUNDAY...THROUGH THE
DAY EXPECT VFR CONDITIONS BUT WINDS WILL INCREASE TO AROUND 15
KNOTS GUSTING INTO THE MID 20 KNOT RANGE KCLE AND POINTS WEST.
FURTHER EAST GUSTS TO NEAR 20.
OUTLOOK...NON-VFR DEVELOPING IN SHOWERS MONDAY THROUGH MONDAY
EVENING ALONG WITH GUSTY WINDS...LINGERING NON VFR NE OH/NW PA ON
TUESDAY.
&&
.MARINE...
THE FIRST QUESTION IS HOW LONG IT WILL TAKE FOR THE SOUTH WINDS TO
INCREASE ENOUGH TO LEAD TO SCA CONDITIONS. RIGHT NOW PLAN TO HOLD
OFF UNTIL SUN NIGHT WITH THE SCA STRENGTH WINDS AS AIR TEMPS WILL BE
ABOVE WATER TEMPS THROUGH SUN. SUN NIGHT PRESSURE GRADIENT AND LOW
LEVEL FLOW LOOK TO GET TOO STRONG TO NOT SEE SOME OF THE SCA FORCE
WINDS MIX DOWN TO LAKE LEVEL.
THE MODELS STILL HAVE A LITTLE DIFFERENCE IN TIMING OF THE STRONG
COLD FRONT ACROSS LAKE ERIE MON. WIND TURN WEST AND SHOULD SEE SCA
CONDITIONS LATE MON UNTIL ABOUT TUE AFTERNOON WHEN HIGH PRESSURE
STARTS TO BUILD INTO THE LAKE TO DIMINISH THE FLOW.
THE HIGH MOVES ACROSS THE LAKE TUE NIGHT INTO WED WHICH SHOULD MEAN
A LIGHT AND CHANGEABLE FLOW. A LIGHT NE TO E FLOW SHOULD DEVELOP AS
THE HIGH MOVE NE OF THE LAKES FOR WED NIGHT INTO THU VEERING TO MORE
SE BY THU NIGHT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MULLEN
NEAR TERM...MULLEN/OUDEMAN
SHORT TERM...MULLEN
LONG TERM...ADAMS
AVIATION...TK
MARINE...ADAMS
AREA FORECAST DISCUSSION...CORRECTED
NWS CLEVELAND OH
800 PM EST SAT NOV 10 2012
.SYNOPSIS...
LOW PRESSURE OVER THE PLAINS TODAY WILL MOVE NORTH INTO CANADA ON
SUNDAY AND PUSH A STRONG COLD FRONT ACROSS THE REGION ON MONDAY.
HIGH PRESSURE WILL DOMINATE THE WEATHER ACROSS THE REGION TUESDAY
THROUGH THE END OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
HIGH PRESSURE WILL DRIFT OFF THE NEW ENGLAND COAST TONIGHT AS LOW
PRESSURE DEEPENS OVER THE NORTHERN PLAINS. THIS SHOULD KEEP A
DECENT SOUTHERLY BREEZE OVERNIGHT WHICH WILL KEEP TEMPERATURES
ELEVATED EVEN WITH A FAIR AMOUNT OF CLEAR SKIES. VARIABLY CLOUDY
THIS EVENING...THEN CLEARING. THE BETTER DOWNSLOPE LOCATIONS WILL
SEE THE WARMEST TEMPERATURES OVERNIGHT. MOST LOCATIONS ACROSS THE
EASTERN HALF OF THE REGION WILL SEE TEMPERATURES 5 TO 10 DEGREES
WARMER THAN LAST NIGHT. A FEW LOCATIONS CLOSER TO THE
LAKESHORE...ESPECIALLY DOWNTOWN CLEVELAND...MAY REMAIN SLIGHTLY
ABOVE 50 DEGREES. NO CHANGE TO THE FORECAST FOR TONIGHT.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY NIGHT/...
THE SOUTHERLY WINDS WILL INCREASE ON SUNDAY WITH A BREEZY TO WINDY
AFTERNOON ANTICIPATED. IF HIGH LEVEL CLOUDINESS REMAINS THIN
ENOUGH MOST LOCATIONS WILL WARM WELL INTO THE 60S WITH SOME 70S
LIKELY. A FEW LOCATIONS WILL APPROACH RECORD LEVELS.
RECORD HIGHS FOR SUNDAY...
TOLEDO 73 IN 1927
FINDLAY 72 IN 1964
MANSFIELD 70 IN 1927
CLEVELAND 73 IN 1915
AKRON/CANTON 72 IN 1915
YOUNGSTOWN 70 IN 1939
ERIE 73 IN 1915
THE WARM TEMPERATURES WILL CONTINUE INTO MONDAY NIGHT WITH THE
SOUTHERLY WINDS AND INCREASING CLOUD COVER. EXPECT TO SEE ALL
LOCATIONS REMAIN IN THE 50S. IF CLOUDS THICKEN AND LOWER FAST
ENOUGH WE MAY SEE A FEW LOCATIONS REMAIN NEAR 60 FOR LOWS.
A STRONG COLD FRONT WILL MOVE INTO THE REGION ON MONDAY WITH RAIN
GRADUALLY SPREADING ACROSS THE AREA FROM WEST TO EAST. AS THE
FRONT PASSES IT WILL FEEL SIGNIFICANTLY COOLER BY THE AFTERNOON.
TEMPERATURES SHOULD ACTUALLY DROP BACK INTO THE 40S IN THE WAKE OF
THE FRONT. THE MAIN SHIELD OF RAIN SHOULD PUSH EAST OF THE REGION
BY MONDAY EVENING. THERE WILL THEN LIKELY BE SOME LAKE EFFECT
SHOWERS/SNOW THAT DEVELOP DOWNWIND OF LAKE ERIE BY TUESDAY
MORNING. THESE WILL MAINLY OCCUR FROM ASHTABULA COUNTY INTO NW PA.
THE SNOW SHOULD BE LIMITED TO INLAND ERIE COUNTY INTO CRAWFORD
COUNTY. DEFINITELY CAN NOT RULE OUT SOME LIGHT ACCUMULATIONS AT
THIS POINT. OTHERWISE IT WILL BE MUCH COOLER ON TUESDAY WITH HIGHS
NOT GETTING OUT OF THE 30S ACROSS THE EASTERN HALF OF THE REGION.
THERE MAY BE A FEW LOWER 40S ACROSS THE WEST WHERE THE SUNSHINE
SHOULD OCCUR.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
HIGH PRESSURE LOOKS TO SET UP JUST NE OF THE LAKES FOR LATE WED INTO
SAT TO PRODUCE DRY CONDITIONS WED AND THU. BY FRI AND SAT THE MODELS
BRING AN UPPER TROUGH INTO THE OH VALLEY. TIMING IS DIFFERENT ON THE
MODELS AND EACH MODEL RUN CONTINUES TO DIFFER SO OVERALL CONFIDENCE
IS LOW AT THIS POINT FOR FRI AND SAT. WITH UPPER TROUGH LIKELY TO BE
OVER OR NEAR THE AREA WILL OPT FOR MORE CLOUDINESS FRI AND SAT AND
UP POPS TO SLIGHT CHANCE.
TEMPS SHOULD SHOW A GRADUAL WARMING TREND WED INTO SAT OF A DEGREE
OR TWO EACH DAY.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
LOOKING AT WINDS AND TEMPS...BEST FIT FOR WARM FRONT PLACEMENT
TAKES IT FROM CENTRAL LWR MI ESE ACROSS LAKE ERIE INTO NERN OHIO.
WINDS AT KERI ARE FRONT 060 DEGREES AND KCLE AND KYNG HAVE BACKED
10 TO 30 DEGREES OVER THE PAST COUPLE HOURS SO FRONT MAY BE
WAFFLING A BIT INTO THE AREA. A QUICK LOOK AT THE HRRR HIGH REZ
WIND FORECAST SUGGESTS THIS STOPS AND REVERSES OVER THE NEXT
COUPLE HOURS TURNING WINDS AT KERI BACK TO SOUTHERLY. HAVE ALSO
SEEN DEVELOPMENT OF A CIG AROUND 45 HUNDRED FEET AT KERI AND
SATELLITE SHOWS A SIMILAR DECK DEVELOPING IN VICINITY OF KCLE AS
WELL. WILL CARRY THIS FOR THE NEXT FEW HOURS BUT WITH THE WARM
FRONT BEGINNING TO MOVE NORTH AGAIN WILL NOT CARRY THROUGH THE
NIGHT. OTHER THAN THAT EXPECT ONLY CONVECTIVE DEBRIS CLOUDS
100-120 FEET TO AFFECT TERMINALS OVERNIGHT. SUNDAY...THROUGH THE
DAY EXPECT VFR CONDITIONS BUT WINDS WILL INCREASE TO AROUND 15
KNOTS GUSTING INTO THE MID 20 KNOT RANGE KCLE AND POINTS WEST.
FURTHER EAST GUSTS TO NEAR 20.
OUTLOOK...NON-VFR DEVELOPING IN SHOWERS MONDAY THROUGH MONDAY
EVENING ALONG WITH GUSTY WINDS...LINGERING NON VFR NE OH/NW PA ON
TUESDAY.
&&
.MARINE...
THE FIRST QUESTION IS HOW LONG IT WILL TAKE FOR THE SOUTH WINDS TO
INCREASE ENOUGH TO LEAD TO SCA CONDITIONS. RIGHT NOW PLAN TO HOLD
OFF UNTIL SUN NIGHT WITH THE SCA STRENGTH WINDS AS AIR TEMPS WILL BE
ABOVE WATER TEMPS THROUGH SUN. SUN NIGHT PRESSURE GRADIENT AND LOW
LEVEL FLOW LOOK TO GET TOO STRONG TO NOT SEE SOME OF THE SCA FORCE
WINDS MIX DOWN TO LAKE LEVEL.
THE MODELS STILL HAVE A LITTLE DIFFERENCE IN TIMING OF THE STRONG
COLD FRONT ACROSS LAKE ERIE MON. WIND TURN WEST AND SHOULD SEE SCA
CONDITIONS LATE MON UNTIL ABOUT TUE AFTERNOON WHEN HIGH PRESSURE
STARTS TO BUILD INTO THE LAKE TO DIMINISH THE FLOW.
THE HIGH MOVES ACROSS THE LAKE TUE NIGHT INTO WED WHICH SHOULD MEAN
A LIGHT AND CHANGEABLE FLOW. A LIGHT NE TO E FLOW SHOULD DEVELOP AS
THE HIGH MOVE NE OF THE LAKES FOR WED NIGHT INTO THU VEERING TO MORE
SE BY THU NIGHT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MULLEN
NEAR TERM...MULLEN/OUDEMAN
SHORT TERM...MULLEN
LONG TERM...ADAMS
AVIATION...TK
MARINE...ADAMS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
649 PM EST SAT NOV 10 2012
.SYNOPSIS...
LOW PRESSURE OVER THE PLAINS TODAY WILL MOVE NORTH INTO CANADA ON
SUNDAY AND PUSH A STRONG COLD FRONT ACROSS THE REGION ON MONDAY.
HIGH PRESSURE WILL DOMINATE THE WEATHER ACROSS THE REGION TUESDAY
THROUGH THE END OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
HIGH PRESSURE WILL DRIFT OFF THE NEW ENGLAND COAST TONIGHT AS LOW
PRESSURE DEEPENS OVER THE NORTHERN PLAINS. THIS SHOULD KEEP A
DECENT SOUTHERLY BREEZE OVERNIGHT WHICH WILL KEEP TEMPERATURES
ELEVATED EVEN WITH A FAIR AMOUNT OF CLEAR SKIES. VARIABLY CLOUDY
THIS EVENING...THEN CLEARING. THE BETTER DOWNSLOPE LOCATIONS WILL
SEE THE WARMEST TEMPERATURES OVERNIGHT. MOST LOCATIONS ACROSS THE
EASTERN HALF OF THE REGION WILL SEE TEMPERATURES 5 TO 10 DEGREES
WARMER THAN LAST NIGHT. A FEW LOCATIONS CLOSER TO THE
LAKESHORE...ESPECIALLY DOWNTOWN CLEVELAND...MAY REMAIN SLIGHTLY
ABOVE 50 DEGREES. NO CHANGE TO THE FORECAST FOR TONIGHT.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY NIGHT/...
THE SOUTHERLY WINDS WILL INCREASE ON SUNDAY WITH A BREEZY TO WINDY
AFTERNOON ANTICIPATED. IF HIGH LEVEL CLOUDINESS REMAINS THIN
ENOUGH MOST LOCATIONS WILL WARM WELL INTO THE 60S WITH SOME 70S
LIKELY. A FEW LOCATIONS WILL APPROACH RECORD LEVELS.
RECORD HIGHS FOR SUNDAY...
TOLEDO 71 IN 1927
FINDLAY 72 IN 1964
MANSFIELD 70 IN 1927
CLEVELAND 73 IN 1915
AKRON/CANTON 72 IN 1915
YOUNGSTOWN 70 IN 1939
ERIE 73 IN 1915
THE WARM TEMPERATURES WILL CONTINUE INTO MONDAY NIGHT WITH THE
SOUTHERLY WINDS AND INCREASING CLOUD COVER. EXPECT TO SEE ALL
LOCATIONS REMAIN IN THE 50S. IF CLOUDS THICKEN AND LOWER FAST
ENOUGH WE MAY SEE A FEW LOCATIONS REMAIN NEAR 60 FOR LOWS.
A STRONG COLD FRONT WILL MOVE INTO THE REGION ON MONDAY WITH RAIN
GRADUALLY SPREADING ACROSS THE AREA FROM WEST TO EAST. AS THE
FRONT PASSES IT WILL FEEL SIGNIFICANTLY COOLER BY THE AFTERNOON.
TEMPERATURES SHOULD ACTUALLY DROP BACK INTO THE 40S IN THE WAKE OF
THE FRONT. THE MAIN SHIELD OF RAIN SHOULD PUSH EAST OF THE REGION
BY MONDAY EVENING. THERE WILL THEN LIKELY BE SOME LAKE EFFECT
SHOWERS/SNOW THAT DEVELOP DOWNWIND OF LAKE ERIE BY TUESDAY
MORNING. THESE WILL MAINLY OCCUR FROM ASHTABULA COUNTY INTO NW PA.
THE SNOW SHOULD BE LIMITED TO INLAND ERIE COUNTY INTO CRAWFORD
COUNTY. DEFINITELY CAN NOT RULE OUT SOME LIGHT ACCUMULATIONS AT
THIS POINT. OTHERWISE IT WILL BE MUCH COOLER ON TUESDAY WITH HIGHS
NOT GETTING OUT OF THE 30S ACROSS THE EASTERN HALF OF THE REGION.
THERE MAY BE A FEW LOWER 40S ACROSS THE WEST WHERE THE SUNSHINE
SHOULD OCCUR.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
HIGH PRESSURE LOOKS TO SET UP JUST NE OF THE LAKES FOR LATE WED INTO
SAT TO PRODUCE DRY CONDITIONS WED AND THU. BY FRI AND SAT THE MODELS
BRING AN UPPER TROUGH INTO THE OH VALLEY. TIMING IS DIFFERENT ON THE
MODELS AND EACH MODEL RUN CONTINUES TO DIFFER SO OVERALL CONFIDENCE
IS LOW AT THIS POINT FOR FRI AND SAT. WITH UPPER TROUGH LIKELY TO BE
OVER OR NEAR THE AREA WILL OPT FOR MORE CLOUDINESS FRI AND SAT AND
UP POPS TO SLIGHT CHANCE.
TEMPS SHOULD SHOW A GRADUAL WARMING TREND WED INTO SAT OF A DEGREE
OR TWO EACH DAY.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
LOOKING AT WINDS AND TEMPS...BEST FIT FOR WARM FRONT PLACEMENT
TAKES IT FROM CENTRAL LWR MI ESE ACROSS LAKE ERIE INTO NERN OHIO.
WINDS AT KERI ARE FRONT 060 DEGREES AND KCLE AND KYNG HAVE BACKED
10 TO 30 DEGREES OVER THE PAST COUPLE HOURS SO FRONT MAY BE
WAFFLING A BIT INTO THE AREA. A QUICK LOOK AT THE HRRR HIGH REZ
WIND FORECAST SUGGESTS THIS STOPS AND REVERSES OVER THE NEXT
COUPLE HOURS TURNING WINDS AT KERI BACK TO SOUTHERLY. HAVE ALSO
SEEN DEVELOPMENT OF A CIG AROUND 45 HUNDRED FEET AT KERI AND
SATELLITE SHOWS A SIMILAR DECK DEVELOPING IN VICINITY OF KCLE AS
WELL. WILL CARRY THIS FOR THE NEXT FEW HOURS BUT WITH THE WARM
FRONT BEGINNING TO MOVE NORTH AGAIN WILL NOT CARRY THROUGH THE
NIGHT. OTHER THAN THAT EXPECT ONLY CONVECTIVE DEBRIS CLOUDS
100-120 FEET TO AFFECT TERMINALS OVERNIGHT. SUNDAY...THROUGH THE
DAY EXPECT VFR CONDITIONS BUT WINDS WILL INCREASE TO AROUND 15
KNOTS GUSTING INTO THE MID 20 KNOT RANGE KCLE AND POINTS WEST.
FURTHER EAST GUSTS TO NEAR 20.
OUTLOOK...NON-VFR DEVELOPING IN SHOWERS MONDAY THROUGH MONDAY
EVENING ALONG WITH GUSTY WINDS...LINGERING NON VFR NE OH/NW PA ON
TUESDAY.
&&
.MARINE...
THE FIRST QUESTION IS HOW LONG IT WILL TAKE FOR THE SOUTH WINDS TO
INCREASE ENOUGH TO LEAD TO SCA CONDITIONS. RIGHT NOW PLAN TO HOLD
OFF UNTIL SUN NIGHT WITH THE SCA STRENGTH WINDS AS AIR TEMPS WILL BE
ABOVE WATER TEMPS THROUGH SUN. SUN NIGHT PRESSURE GRADIENT AND LOW
LEVEL FLOW LOOK TO GET TOO STRONG TO NOT SEE SOME OF THE SCA FORCE
WINDS MIX DOWN TO LAKE LEVEL.
THE MODELS STILL HAVE A LITTLE DIFFERENCE IN TIMING OF THE STRONG
COLD FRONT ACROSS LAKE ERIE MON. WIND TURN WEST AND SHOULD SEE SCA
CONDITIONS LATE MON UNTIL ABOUT TUE AFTERNOON WHEN HIGH PRESSURE
STARTS TO BUILD INTO THE LAKE TO DIMINISH THE FLOW.
THE HIGH MOVES ACROSS THE LAKE TUE NIGHT INTO WED WHICH SHOULD MEAN
A LIGHT AND CHANGEABLE FLOW. A LIGHT NE TO E FLOW SHOULD DEVELOP AS
THE HIGH MOVE NE OF THE LAKES FOR WED NIGHT INTO THU VEERING TO MORE
SE BY THU NIGHT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MULLEN
NEAR TERM...MULLEN/OUDEMAN
SHORT TERM...MULLEN
LONG TERM...ADAMS
AVIATION...TK
MARINE...ADAMS
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
338 PM CST FRI NOV 9 2012
.DISCUSSION.../ISSUED AT 338 PM CST/
COMPLICATED FORECAST THROUGH SATURDAY NIGHT AS A STRONG AREA OF LOW
PRESSURE PUSHES TOWARDS THE REGION. FOR TONIGHT...EXPECT ANOTHER
AREA OF STRATUS TO FORM OVER EASTERN NEBRASKA AND MOVE NORTH INTO
OUR REGION. THIS AREA WILL LIKELY KEEP LOCATIONS ALONG AND NORTH OF
INTERSTATE 90 LOCKED IN THE CLOUDS MUCH OF THE NIGHT. LOCATIONS TO
THE SOUTH MAY SEE THIS STRATUS ACTUALLY LIFT NORTH OF THEM FOR A
PERIOD TONIGHT. EITHER WAY STILL EXPECTING LOW STRATUS TO REFORM
LATE TONIGHT INTO TOMORROW MORNING OVER MUCH OF THE AREA...WITH
AREAS OF FOG ALSO LIKELY. DRIZZLE SHOULD BE CONFINED TO OUR
NORTHEAST AREAS WHERE SOME WEAK LIFT WILL COINCIDE WITH THE DEEPEST
LOW LEVEL MOISTURE. NOT EXPECTING MUCH IF ANY MEASURABLE PRECIP
TONIGHT AS FORCING REMAINS WEAK AND MOISTURE SHALLOW. LOWS WONT DROP
TOO MUCH...AS THE CLOUDS...A BREEZE AND LOW LEVEL MOISTURE ADVECTION
WILL KEEP THEM IN THE 40S TO NEAR 50.
MODELS ARE TRENDING SLOWER WITH THE SYSTEM AND COLD FRONT FOR
SATURDAY. AS THE WARM FRONT LIFTS NORTH...STRONG SOUTHWESTERLY
FLOW SHOULD BE PRETTY EFFECTIVE AT DISSIPATING THE STRATUS. THUS IT
SHOULD BE QUITE THE WARM DAY ACROSS THE SOUTHEAST HALF OF THE AREA
WITH HIGHS IN THE 60S AND LOW 70S. WINDS WILL BE STRONG ACROSS
NORTHWEST IOWA AND PORTIONS OF SOUTHWEST MINNESOTA WITH BOUNDARY
LAYER MEAN WINDS APPROACHING 30 KTS. MAY EVEN END UP CLOSE TO WIND
ADVISORY CRITERIA...BUT WILL LET FUTURE SHIFTS TAKE ANOTHER LOOK.
FRONT SHOULD ENTER OUR WEST BY AROUND NOON...APPROACH INTERSTATE 29
BY MID AFTERNOON AND EXIT THE CWA DURING THE EVENING. WINDS WILL BE
STRONG OUT OF THE NORTHWEST BEHIND THE FRONT...WITH NEAR ADVISORY
CRITERIA ALSO POSSIBLE WEST OF THE JAMES RIVER. TOTAL PRECIP FROM
THE SYSTEM SHOULD BE GENERALLY UNDER A QUARTER INCH WEST OF
INTERSTATE 29 AND A QUARTER TO ISOLATED HALF INCH AMOUNTS TO THE
EAST...HEAVILY DEPENDENT ON ANY CONVECTIVE DEVELOPMENT SATURDAY
EVENING.
OTHER THINGS OF NOTE WILL BE SEVERE WEATHER POTENTIAL AHEAD OF THE
FRONT AND SNOW BEHIND IT. SEVERE POTENTIAL LOOKS PRETTY MINIMAL
ACROSS OUR CWA. STRONG CAPPING LOOKS PREVALENT AHEAD OF THE FRONT
AND THE BEST FRONTAL CONVERGENCE SHOULD STAY SOUTH OF OUR CWA. MOST
OF THE ACTIVITY LOOKS POST FRONTAL FOR US...WITH POSSIBLY AN AREA OF
ELEVATED THUNDERSTORMS EAST OF INTERSTATE 29. WILL HAVE TO CONTINUE
TO MONITOR THOUGH...ESPECIALLY ACROSS OUR FAR SOUTHEAST COUPLE
COUNTIES. IT IS POSSIBLE THAT A FEW STORMS COULD FORM OVER EASTERN
NEBRASKA AHEAD OF THE FRONT AND MOVE NORTHEAST AND CLIP OUR AREA
SATURDAY EVENING. ANY PRE FRONTAL CONVECTION WOULD HAVE THE
POTENTIAL OF BECOMING SEVERE...WITH IMPRESSIVE WIND PROFILES NOTED
ON SOUNDINGS...MAIN THREAT WOULD BE STRONG WINDS. ANY SNOW THREAT
WILL BE AS THE MID LEVEL FRONT MOVES ACROSS...AS THE BEST DYNAMICAL
LIFT STAYS TO OUR NORTHWEST. RAIN SHOULD MIX WITH AND CHANGE TO SNOW
FROM WEST TO EAST SATURDAY NIGHT. CURRENT INDICATIONS ARE THAT MUCH
OF THE SNOW STAYS TO OUR NORTHWEST CLOSER TO THE BETTER LIFT. THUS
ONLY THINKING AROUND AN INCH OF SNOW ALONG AND WEST OF THE JAMES
RIVER...WITH UNDER AN INCH ELSEWHERE. /CHENARD
SUNDAY BY FAR THE QUIETER DAY OF THE WEEKEND...WITH UPPER WAVE
LIFTING OFF TO THE NORTHEAST AND COLD FRONT/ASSOCIATED MID LEVEL
FRONT PUSHING EAST OF THE CWA. WILL HANG ONTO SOME SMALL POPS IN THE
FAR SOUTHEAST FOR LINGERING LIGHT PRECIP WITH THE MID LEVEL FRONT...
AND SLIGHT CHANCE OF LIGHT SNOW BAND LIFTING NORTH OUT WESTERN CWA.
OTHERWISE EXPECT TO SEE DECENT CLEARING ACROSS THE SOUTH WITH SOME
POTENTIAL FOR AFTERNOON STRATOCU DEVELOPMENT IN THE NORTH AS
TRAILING WAVE SWINGS ACROSS THE EASTERN DAKOTAS. TEMPERATURES WILL
BE SHARPLY COLDER THAN SATURDAY...THOUGH WITH THE POTENTIAL FOR AT
LEAST PARTLY SUNNY SKIES AND STRONG MIXING IN POST FRONTAL AIR
MASS...THINK TEMPERATURES ACROSS THE WEST/NORTH WILL BE ABLE TO
RECOVER A FEW DEGREES FROM MORNING LOWS INTO THE MID-UPPER 20S...
WHILE SOUTHEAST AREAS REMAIN FAIRLY STEADY IN THE LOWER 30S. WILL
FEEL MORE RAW THOUGH...AS GUSTY WEST-NORTHWEST WINDS PUSH WIND CHILL
VALUES INTO THE TEENS MOST OF THE DAY. WINDS STAY UP IN CONTINUED
NORTHWEST FLOW SUNDAY NIGHT...WHICH WILL KEEP TEMPS FROM COMPLETELY
BOTTOMING OUT...THOUGH LOWS IN THE TEENS STILL LOOK REASONABLE GIVEN
COLD AIR MASS.
UPPER TROUGH EXITS OFF TO THE EAST THROUGH THE GREAT LAKES MONDAY
WITH QUASI-ZONAL FLOW THEN DOMINATING THROUGH MOST OF NEXT WEEK.
TEMPERATURES WILL REMAIN QUITE COOL ON MONDAY...THOUGH TEMPERATURE
GRADIENT WILL PIVOT TO A MORE NORTHWEST-SOUTHEAST ORIENTATION...WITH
HIGHS FROM MID-UPPER 20S IN SOUTHWEST MN TO LOWER 30S THROUGH THE
MISSOURI VALLEY. MODERATION IN TEMPERATURES WILL BEGIN TUESDAY AS
SOUTHERLY FLOW KICKS IN BEHIND THE SURFACE RIDGE. ANY SNOWFALL FROM
THIS WEEKENDS SYSTEM COULD HOLD TEMPS BACK A BIT IN THE WEST...BUT
SHOULD GENERALLY SEE HIGHS IN THE UPPER 30S TO MID 40S TUESDAY.
EXPECT WEDNESDAY TO BE WARMEST DAY OF THE WEEK...WITH HIGHS AT LEAST
IN THE MID 40S TO LOWER 50S AS 925MB TEMPS WARM BACK INTO THE 5-10C
RANGE AHEAD OF WEAK COOL FRONT WHICH PUSHES SOUTHEAST THROUGH THE
REGION WEDNESDAY NIGHT.
MODELS SHOWING A WEAK WAVE KICKING OUT INTO THE PLAINS LATE NEXT
WEEK FRIDAY/SATURDAY TIME FRAME. 09/12Z RUN OF ECMWF IS A LITTLE
FASTER WITH THIS THAN ITS 09/00Z COUNTERPART...AND THAN THE 09/12Z
GFS. WITH UNCERTAINTY IN THE TIMING AT THIS RANGE...WILL KEEP THE
FORECAST DRY FOR NOW WITH SEASONABLE HIGHS IN THE 40S FOR THURSDAY
AND FRIDAY.
&&
.AVIATION.../FOR THE 18Z TAF ISSUANCE/
COMPLICATED AND LOW CONFIDENCE TAF FORECAST THROUGH 18Z SATURDAY.
CURRENTLY SEEING STATUS RANGING FROM LIFR TO MVFR...WHICH IS SLOWLY
ERODING FROM EAST TO WEST. RAP AND HRRR SEEMS TO BE HANDLING THIS
THE BEST...ALTHOUGH IT IS LIKELY A LITTLE TO FAST WITH THE CLEARING.
THUS EXPECT CLEARING TO REACH KFSD THIS AFTERNOON FOR A BRIEF
TIME...WITH KHON LIKELY STAYING STUCK IN THE CLOUDS. ANOTHER AREA OF
STRATUS WILL REFORM THIS AFTERNOON TO OUR SOUTH AND MOVE NORTH INTO
THIS EVENING. THUS CIGS WILL DROP BACK DOWN INTO THE IFR RANGE BY
TONIGHT...WITH AREAS OF FOG AND DRIZZLE ALSO POSSIBLE. SOME LIFR
ONCE AGAIN SEEMS LIKELY LATE TONIGHT INTO TOMORROW MORNING.
SOUTHWESTERLY WINDS AHEAD OF THE FRONT SHOULD HELP MIX OUT THE
STRATUS QUICKER TOMORROW...WITH IT BEGINNING TO LIFT FROM SOUTH TO
NORTH BY 18Z. /CHENARD
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1108 AM CST FRI NOV 9 2012
.DISCUSSION.../ISSUED AT 1035 AM CST/
TRICKY FORECAST FOR TODAY WITH LOW STRATUS AND AREAS OF FOG
CURRENTLY HANGING TOUGH ACROSS ALL BUT THE FAR SOUTHEAST PORTION OF
THE CWA. HRRR AND RUC ARE HANDLING THE CURRENT SITUATION WELL...BUT
BOTH APPEAR TO SCOUR OUT THE STRATUS TOO QUICKLY LATE THIS
MORNING...GIVEN EASTERLY WIND COMPONENT ACTING TO SLOW EROSION.
MEANWHILE A SECOND AREA OF STRATUS WILL LIKELY FORM THIS AFTERNOON
TO OUR SOUTH AND PUSH INTO OUR AREA THIS AFTERNOON. GFS SEEMS TOO
AGGRESSIVE WITH THIS. SO WE SHOULD SEE SOME DECENT SUN TODAY IN OUR
FAR SOUTHEAST. THINKING OTHER AREAS STAY MAINLY CLOUDY...AS BY THE
TIME THE CURRENT STATUS BEGINS TO ERODE...OUR NEXT BATCH WILL BE
MOVING IN FROM THE SOUTH. TRENDED TEMPERATURES DOWN TOWARDS THE
COOLER MAV...EXCEPT ACROSS OUR SOUTHEAST WHERE DECENT SUN SHOULD
STILL ALLOW MID OR EVEN UPPER 50S BY THIS AFTERNOON. /CHENARD
.PREVIOUS DISCUSSION.../ISSUED AT 427 AM CST/
BOUNDARY HAS SETTLED SOUTH OF THE CWA OVERNIGHT...AND IN WAKE A
FAIRLY WIDESPREAD STRATUS FIELD ACROSS THE NORTHERN AND WESTERN CWA.
DEALING WITH THE STRATUS AND IMPACT ON TEMPERATURES IS THE MAIN
ISSUE FOR TODAY. DRY AIR POISED TO THE EAST WILL LIKELY ERODE
STRATUS...WHICH EVEN FOR THE CURRENT TIME HAS A DECENT NORTHEAST
WIND SHADOW OFF THE BUFFALO RIDGE. STRATUS LOOKS MOST DIFFICULT TO
SHAKE IN THE NORTHWESTERN/WESTERN AREAS FROM KHON TOWARD LOWER BRULE
LOCATIONS...AND IN THESE AREAS LOWERED HIGHS BY SEVERAL DEGREES.
CONVERSELY...AREAS IN THE FAR SOUTHEAST WILL FIND STRATUS VACANT
FROM SKIES FOR A GOOD PART OF THE DAY...ALTHOUGH A FAIR COVERAGE OF
HIGH CLOUDS WILL STREAM THROUGH SKIES TODAY. MAINTAINED WARMER
READINGS SOUTHEAST...AND EVEN NUDGED UP IN THE FAR SOUTHEAST.
HOWEVER...NOTE ON EVENING RAOB ANALYSIS AREA OF ELEVATED MOISTURE
RETURN WITH 5-10C 850 HPA DEWPOINTS FROM OK INTO KS. AREA OF LOWER
TO MID 50S DEWPOINTS WORKING NORTHWARD AT SURFACE EVEN INTO
SOUTHERN KS AT THIS TIME. AS FLOW ALOFT TURNS MORE SOUTHERLY AND
STRENGTHENS...THE MOISTURE WORKS NORTHWARD AND LOOKS TO IMPACT AREA
STARTING AFT 21Z. SHOULD SEE INCREASE IN STRATUS WITH SOUNDINGS
CAPPING OFF MOISTURE ABOVE AS ELEVATED MIXED LAYER INCREASES THROUGH
THE DAY WITH SOUTHWEST MID LEVEL FLOW.
THIS STRATUS SHOULD CONTINUE TO BECOME MORE WIDESPREAD OVERNIGHT
NORTH OF WARM FRONT LIFTING THROUGH EASTERN NEBRASKA AND IOWA.
INCREASING SHEAR ATOP THE MOIST LAYER IS A LIKELY DRIZZLE
INITIATOR...AND WILL ALSO SEE FOG POTENTIAL INCREASE THROUGH THE
NIGHT...ESPECIALLY FOR HIGHER TERRAIN AS TOP DOWN SATURATION OCCURS.
LOWS WILL REMAIN QUITE MILD WITH THE CLOUD COVER AND INCREASING
MOISTURE...NOT TOO FAR BELOW NORMAL HIGHS...MAINLY IN THE 40S.
PRESENCE OF ELEVATED MIXED LAYER WITH WEAK WAVE RIPPLING NORTHEAST
COULD BRING A COUPLE OF LEGITIMATE LIGHT SHOWERS TO THE EASTERN CWA
LATER TONIGHT...BUT DID COVER A LOW MEASURABLE POP WITH DRIZZLE
THREAT.
CHANGES AND CHALLENGES BEGIN SATURDAY AS LARGE TROUGH IN
INTERMOUNTAIN WEST PUSHES TOWARD THE ROCKIES. PRESSURE FALLS IN THE
WESTERN PLAINS AND DEVELOPING LOW PRESSURE...WILL START TO PULL OUT
INTO THE REGION ALONG WITH A VERY STRONG COLD FRONT. BOUNDARY NOW
APPEARS TO BE JUST A TOUCH SLOWER TREND TO A FEW MODELS...WHICH WILL
OPEN THE WINDOW FOR SOME SLIGHTLY WARMER HIGHS IN THE SOUTHEAST
WHICH WILL BUST INTO THE WARM SECTOR IN THE AFTERNOON. 925 HPA TEMPS
OVERALL WOULD MIX INTO THE LOWER TO MID 70S FOR MUCH OF THE AREA
EAST OF INTERSTATE 29 AND SOUTH OF INTERSTATE 90...BUT A STRONG
INVERSION WILL BE IN PLACE TO LIMIT MIXING POTENTIAL...AND ALSO WILL
HELP TO POOL DEWPOINTS INTO THE 50S. EARLY DAY WILL SEE THE
STRATUS/DRIZZLE LIFTING NORTHWARD...AS INVERTED TROUGH WANDERS
TOWARD THE FAR WESTERN CWA. HIGHS REACHED EARLY IN THE DAY...
PERHAPS AS LATE AS MIDDAY FAR WEST...BEFORE STRONG COLD AIR
ADVECTION SLAMS INTO THE AREA. ECMWF PREFERRED OVERALL WITH
EVOLUTION OF THE VERY AMPLIFIED SYSTEM...WHICH HAS ALSO BEEN QUITE
CONSISTENT WITH OVERALL STRUCTURE.
NOT FULLY SUBSCRIBING TO THE SEVERE THREAT FOR SOUTHEASTERN THIRD OF
CWA...WITH TWO MAJOR CONCERNS BEING TOO MUCH SHEAR WITH 500 HPA
WINDS CLOSE TO 80 KNOTS...AND THE VERY CAPPED LOWER LEVELS IN PRE
FRONTAL ENVIRONMENT. AGAIN WOULD LIKELY TAKE STORMS DEVELOPING
OUTSIDE THE AREA...PERHAPS SOUTHERN NEBRASKA OR NORTHERN KANSAS...TO
RACE NORTHEAST. DID INCREASE THE EVENING POPS ACROSS NORTHWEST IOWA
TO ACCOUNT FOR THIS DEVELOPMENT/ADVECTION...WITH ONLY A VERY OUTSIDE
CHANCE FOR A SEVERE WIND GUST.
THE COLD SIDE OF THE SYSTEM PRESENTING CHALLENGES OF ITS OWN. MODELS
ARE FAR FROM AGREEING ON PRECIPITATION STRUCTURE WITHIN THE SYSTEM.
AGAIN...SIDING MORE WITH THE ECMWF/CANADIAN REGIONAL AND TO LESSER
EXTENT THE GFS /WHICH IS A NOT IMPOSSIBLE OUTLIER TOO SLOW WITH
BOUNDARY DUE TO STRONGER SECONDARY ENERGY HANGING SOUTH/... WOULD
FOCUS SOME BETTER PRECIP EVEN INTO SUNDAY THROUGH THE EASTERN CWA.
RAIN WILL START TO TRANSITION TO SNOW BY EARLY EVENING WEST OF THE
JAMES...AND ESPECIALLY MAKE INROADS TOWARDS 06Z WHEN UPPER PV SURGE
STARTS TO WORK NORTHWARD ALONG THE BOUNDARY. NOT TERRIBLY UNSTABLE
ABOVE FRONTAL SURFACE...SO NOT EXPECTING MORE THAN BROAD AREA OF
PRECIPITATION...PERHAPS WEAKLY FOCUSED FOR A WHILE AROUND 03Z-09Z.
SREF INDICATING VERY LITTLE FREEZING POTENTIAL...BUT STILL CAN SEE
WHERE SATURATION AHEAD OF THE MAIN MID LEVEL BOUNDARY AS COLD AIR
RUSHES AHEAD...MAY FIND LACK OF ICE PROCESSES IN PLACE TO SUPPORT
SOME PATCHY FREEZING DRIZZLE LATER SATURDAY NIGHT OR EARLY SUNDAY
FROM NEAR I29 AND EASTWARD. LINGERING FRONTAL BAND WILL WANE RAPIDLY
SUNDAY MORNING...AND ADDITIONAL ACCUMULATIONS WILL BE GENERALLY A
HALF INCH OR LESS AND MAINLY EARLY...AND TOTAL SNOW ACCUMULATIONS AS
A RESULT WILL DROP OFF SHARPLY EAST OF A MARSHALL TO SIOUX FALLS TO
YANKTON LINE...WITH AN INCH OR TWO WEST AND A HALF INCH OR MUCH LESS
EAST.
WINDY SUNDAY AND BREEZY MONDAY...BOTH WITH MUCH COOLER THAN NORMAL
TEMPERATURES. OVERALL WEATHER WILL BE QUIET BEYOND SUNDAY MORNING...
AND ONLY REAL CHANGES TO GUIDANCE WAS TO LOWER LOWS A BIT MORE ON
TUESDAY MORNING AS WEAK RIDGE SLIDES ACROSS THE AREA...AND RETURN
FLOW NOT EXPECTED TO BE TOO EFFECTIVE IN KEEPING WARM. LARGE SCALE
DISAGREEMENT BETWEEN MODELS TOWARD LATE WEEK...SO KEPT THINGS CLOSER
TO THE CONSENSUS. /CHAPMAN
&&
.AVIATION.../FOR THE 18Z TAF ISSUANCE/
COMPLICATED AND LOW CONFIDENCE TAF FORECAST THROUGH 18Z SATURDAY.
CURRENTLY SEEING STATUS RANGING FROM LIFR TO MVFR...WHICH IS SLOWLY
ERODING FROM EAST TO WEST. RAP AND HRRR SEEMS TO BE HANDLING THIS
THE BEST...ALTHOUGH IT IS LIKELY A LITTLE TO FAST WITH THE CLEARING.
THUS EXPECT CLEARING TO REACH KFSD THIS AFTERNOON FOR A BRIEF
TIME...WITH KHON LIKELY STAYING STUCK IN THE CLOUDS. ANOTHER AREA OF
STRATUS WILL REFORM THIS AFTERNOON TO OUR SOUTH AND MOVE NORTH INTO
THIS EVENING. THUS CIGS WILL DROP BACK DOWN INTO THE IFR RANGE BY
TONIGHT...WITH AREAS OF FOG AND DRIZZLE ALSO POSSIBLE. SOME LIFR
ONCE AGAIN SEEMS LIKELY LATE TONIGHT INTO TOMORROW MORNING.
SOUTHWESTERLY WINDS AHEAD OF THE FRONT SHOULD HELP MIX OUT THE
STRATUS QUICKER TOMORROW...WITH IT BEGINNING TO LIFT FROM SOUTH TO
NORTH BY 18Z. /CHENARD
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1035 AM CST FRI NOV 9 2012
.DISCUSSION.../ISSUED AT 1035 AM CST/
TRICKY FORECAST FOR TODAY WITH LOW STRATUS AND AREAS OF FOG
CURRENTLY HANGING TOUGH ACROSS ALL BUT THE FAR SOUTHEAST PORTION OF
THE CWA. HRRR AND RUC ARE HANDLING THE CURRENT SITUATION WELL...BUT
BOTH APPEAR TO SCOUR OUT THE STRATUS TOO QUICKLY LATE THIS
MORNING...GIVEN EASTERLY WIND COMPONENT ACTING TO SLOW EROSION.
MEANWHILE A SECOND AREA OF STRATUS WILL LIKELY FORM THIS AFTERNOON
TO OUR SOUTH AND PUSH INTO OUR AREA THIS AFTERNOON. GFS SEEMS TOO
AGGRESSIVE WITH THIS. SO WE SHOULD SEE SOME DECENT SUN TODAY IN OUR
FAR SOUTHEAST. THINKING OTHER AREAS STAY MAINLY CLOUDY...AS BY THE
TIME THE CURRENT STATUS BEGINS TO ERODE...OUR NEXT BATCH WILL BE
MOVING IN FROM THE SOUTH. TRENDED TEMPERATURES DOWN TOWARDS THE
COOLER MAV...EXCEPT ACROSS OUR SOUTHEAST WHERE DECENT SUN SHOULD
STILL ALLOW MID OR EVEN UPPER 50S BY THIS AFTERNOON. /CHENARD
.PREVIOUS DISCUSSION.../ISSUED AT 427 AM CST/
BOUNDARY HAS SETTLED SOUTH OF THE CWA OVERNIGHT...AND IN WAKE A
FAIRLY WIDESPREAD STRATUS FIELD ACROSS THE NORTHERN AND WESTERN CWA.
DEALING WITH THE STRATUS AND IMPACT ON TEMPERATURES IS THE MAIN
ISSUE FOR TODAY. DRY AIR POISED TO THE EAST WILL LIKELY ERODE
STRATUS...WHICH EVEN FOR THE CURRENT TIME HAS A DECENT NORTHEAST
WIND SHADOW OFF THE BUFFALO RIDGE. STRATUS LOOKS MOST DIFFICULT TO
SHAKE IN THE NORTHWESTERN/WESTERN AREAS FROM KHON TOWARD LOWER BRULE
LOCATIONS...AND IN THESE AREAS LOWERED HIGHS BY SEVERAL DEGREES.
CONVERSELY...AREAS IN THE FAR SOUTHEAST WILL FIND STRATUS VACANT
FROM SKIES FOR A GOOD PART OF THE DAY...ALTHOUGH A FAIR COVERAGE OF
HIGH CLOUDS WILL STREAM THROUGH SKIES TODAY. MAINTAINED WARMER
READINGS SOUTHEAST...AND EVEN NUDGED UP IN THE FAR SOUTHEAST.
HOWEVER...NOTE ON EVENING RAOB ANALYSIS AREA OF ELEVATED MOISTURE
RETURN WITH 5-10C 850 HPA DEWPOINTS FROM OK INTO KS. AREA OF LOWER
TO MID 50S DEWPOINTS WORKING NORTHWARD AT SURFACE EVEN INTO
SOUTHERN KS AT THIS TIME. AS FLOW ALOFT TURNS MORE SOUTHERLY AND
STRENGTHENS...THE MOISTURE WORKS NORTHWARD AND LOOKS TO IMPACT AREA
STARTING AFT 21Z. SHOULD SEE INCREASE IN STRATUS WITH SOUNDINGS
CAPPING OFF MOISTURE ABOVE AS ELEVATED MIXED LAYER INCREASES THROUGH
THE DAY WITH SOUTHWEST MID LEVEL FLOW.
THIS STRATUS SHOULD CONTINUE TO BECOME MORE WIDESPREAD OVERNIGHT
NORTH OF WARM FRONT LIFTING THROUGH EASTERN NEBRASKA AND IOWA.
INCREASING SHEAR ATOP THE MOIST LAYER IS A LIKELY DRIZZLE
INITIATOR...AND WILL ALSO SEE FOG POTENTIAL INCREASE THROUGH THE
NIGHT...ESPECIALLY FOR HIGHER TERRAIN AS TOP DOWN SATURATION OCCURS.
LOWS WILL REMAIN QUITE MILD WITH THE CLOUD COVER AND INCREASING
MOISTURE...NOT TOO FAR BELOW NORMAL HIGHS...MAINLY IN THE 40S.
PRESENCE OF ELEVATED MIXED LAYER WITH WEAK WAVE RIPPLING NORTHEAST
COULD BRING A COUPLE OF LEGITIMATE LIGHT SHOWERS TO THE EASTERN CWA
LATER TONIGHT...BUT DID COVER A LOW MEASURABLE POP WITH DRIZZLE
THREAT.
CHANGES AND CHALLENGES BEGIN SATURDAY AS LARGE TROUGH IN
INTERMOUNTAIN WEST PUSHES TOWARD THE ROCKIES. PRESSURE FALLS IN THE
WESTERN PLAINS AND DEVELOPING LOW PRESSURE...WILL START TO PULL OUT
INTO THE REGION ALONG WITH A VERY STRONG COLD FRONT. BOUNDARY NOW
APPEARS TO BE JUST A TOUCH SLOWER TREND TO A FEW MODELS...WHICH WILL
OPEN THE WINDOW FOR SOME SLIGHTLY WARMER HIGHS IN THE SOUTHEAST
WHICH WILL BUST INTO THE WARM SECTOR IN THE AFTERNOON. 925 HPA TEMPS
OVERALL WOULD MIX INTO THE LOWER TO MID 70S FOR MUCH OF THE AREA
EAST OF INTERSTATE 29 AND SOUTH OF INTERSTATE 90...BUT A STRONG
INVERSION WILL BE IN PLACE TO LIMIT MIXING POTENTIAL...AND ALSO WILL
HELP TO POOL DEWPOINTS INTO THE 50S. EARLY DAY WILL SEE THE
STRATUS/DRIZZLE LIFTING NORTHWARD...AS INVERTED TROUGH WANDERS
TOWARD THE FAR WESTERN CWA. HIGHS REACHED EARLY IN THE DAY...
PERHAPS AS LATE AS MIDDAY FAR WEST...BEFORE STRONG COLD AIR
ADVECTION SLAMS INTO THE AREA. ECMWF PREFERRED OVERALL WITH
EVOLUTION OF THE VERY AMPLIFIED SYSTEM...WHICH HAS ALSO BEEN QUITE
CONSISTENT WITH OVERALL STRUCTURE.
NOT FULLY SUBSCRIBING TO THE SEVERE THREAT FOR SOUTHEASTERN THIRD OF
CWA...WITH TWO MAJOR CONCERNS BEING TOO MUCH SHEAR WITH 500 HPA
WINDS CLOSE TO 80 KNOTS...AND THE VERY CAPPED LOWER LEVELS IN PRE
FRONTAL ENVIRONMENT. AGAIN WOULD LIKELY TAKE STORMS DEVELOPING
OUTSIDE THE AREA...PERHAPS SOUTHERN NEBRASKA OR NORTHERN KANSAS...TO
RACE NORTHEAST. DID INCREASE THE EVENING POPS ACROSS NORTHWEST IOWA
TO ACCOUNT FOR THIS DEVELOPMENT/ADVECTION...WITH ONLY A VERY OUTSIDE
CHANCE FOR A SEVERE WIND GUST.
THE COLD SIDE OF THE SYSTEM PRESENTING CHALLENGES OF ITS OWN. MODELS
ARE FAR FROM AGREEING ON PRECIPITATION STRUCTURE WITHIN THE SYSTEM.
AGAIN...SIDING MORE WITH THE ECMWF/CANADIAN REGIONAL AND TO LESSER
EXTENT THE GFS /WHICH IS A NOT IMPOSSIBLE OUTLIER TOO SLOW WITH
BOUNDARY DUE TO STRONGER SECONDARY ENERGY HANGING SOUTH/... WOULD
FOCUS SOME BETTER PRECIP EVEN INTO SUNDAY THROUGH THE EASTERN CWA.
RAIN WILL START TO TRANSITION TO SNOW BY EARLY EVENING WEST OF THE
JAMES...AND ESPECIALLY MAKE INROADS TOWARDS 06Z WHEN UPPER PV SURGE
STARTS TO WORK NORTHWARD ALONG THE BOUNDARY. NOT TERRIBLY UNSTABLE
ABOVE FRONTAL SURFACE...SO NOT EXPECTING MORE THAN BROAD AREA OF
PRECIPITATION...PERHAPS WEAKLY FOCUSED FOR A WHILE AROUND 03Z-09Z.
SREF INDICATING VERY LITTLE FREEZING POTENTIAL...BUT STILL CAN SEE
WHERE SATURATION AHEAD OF THE MAIN MID LEVEL BOUNDARY AS COLD AIR
RUSHES AHEAD...MAY FIND LACK OF ICE PROCESSES IN PLACE TO SUPPORT
SOME PATCHY FREEZING DRIZZLE LATER SATURDAY NIGHT OR EARLY SUNDAY
FROM NEAR I29 AND EASTWARD. LINGERING FRONTAL BAND WILL WANE RAPIDLY
SUNDAY MORNING...AND ADDITIONAL ACCUMULATIONS WILL BE GENERALLY A
HALF INCH OR LESS AND MAINLY EARLY...AND TOTAL SNOW ACCUMULATIONS AS
A RESULT WILL DROP OFF SHARPLY EAST OF A MARSHALL TO SIOUX FALLS TO
YANKTON LINE...WITH AN INCH OR TWO WEST AND A HALF INCH OR MUCH LESS
EAST.
WINDY SUNDAY AND BREEZY MONDAY...BOTH WITH MUCH COOLER THAN NORMAL
TEMPERATURES. OVERALL WEATHER WILL BE QUIET BEYOND SUNDAY MORNING...
AND ONLY REAL CHANGES TO GUIDANCE WAS TO LOWER LOWS A BIT MORE ON
TUESDAY MORNING AS WEAK RIDGE SLIDES ACROSS THE AREA...AND RETURN
FLOW NOT EXPECTED TO BE TOO EFFECTIVE IN KEEPING WARM. LARGE SCALE
DISAGREEMENT BETWEEN MODELS TOWARD LATE WEEK...SO KEPT THINGS CLOSER
TO THE CONSENSUS. /CHAPMAN
&&
.AVIATION.../FOR THE 12Z TAF ISSUANCE/
IFR CEILINGS WILL BE IN PLACE OVER MOST OF THE AREA THROUGH MID TO
LATE MORNING. A SLIGHTLY DRIER FLOW OF AIR FROM THE EAST WILL AID IN
BREAKING UP SOME OF THIS STRATUS DURING THE AFTERNOON. CEILINGS WILL
LIKELY CLIMB BACK INTO THE MVFR CATEGORY BY LATE THIS MORNING AND
POSSIBLY INTO LOW END VFR. AREAS EAST OF INTERSTATE 29 COULD SEE
SCATTERED CLOUD COVER FOR A TIME TODAY. BUT LOWER CEILINGS WILL
AGAIN BE LIKELY OVERNIGHT AS WELL AS THE THREAT FOR SOME FOG AND
DRIZZLE...ESPECIALLY ALONG AND EAST OF INTERSTATE 29. CEILINGS AND
VISIBILITIES WILL LIKELY DROP INTO THE IFR CATEGORY. /08
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1158 PM CST THU NOV 8 2012
.DISCUSSION.../ISSUED AT 900 PM CST/
COLD FRONT MOVING SOUTHEAST THROUGH NORTHWEST IOWA WITH STRATUS
SPREADING SOUTH ACROSS CWA. CURRENTLY STRATUS IS NEAR I90 AND WEST
OF BUFFALO RIDGE IN SOUTHWEST MINNESOTA. STRATUS MAY HAVE A HARD
TIME GETTING EAST OF BUFFALO RIDGE TONIGHT WITH THE LOW LEVEL
NORTHEAST FLOW KEEPING THE CLOUDS TO THE WEST. WILL TREND MOST OF
NIGHT CLOUDS SAGGING SOUTH WEST OF BUFFALO RIDGE...BUT OVER
TIME...STRATUS SHOULD MOVE IN. CLOUDS SHOULD HELP TO HOLD UP
TEMPERATURES TONIGHT...AND DID BUMP UP A FEW DEGREES ACROSS THE
NORTH.
&&
.AVIATION.../FOR THE 06Z TAF ISSUANCE/
IFR CEILINGS WILL BE IN PLACE OVER MOST OF THE AREA THROUGH MID
MORNING. PARTS OF NORTHWEST IOWA COULD AVOID THIS STRATUS...BUT FOG
COULD FILL IN LATE TONIGHT IN AREAS NEAR THE EDGE OF STRATUS. MUCH
OF THIS STRATUS WILL BREAK UP A BIT FROM THE EAST AS DRIER AIR
PUSHES IN. CEILINGS WILL LIKELY LIMB BACK INTO THE MVFR CATEGORY BY
LATE FRIDAY MORNING AND POSSIBLY INTO LOW END VFR. AREAS EAST OF
INTERSTATE 29 COULD SEE SCATTERED CLOUD COVER FOR A TIME TODAY. /08
&&
.PREVIOUS DISCUSSION.../ISSUED AT 356 PM CST/
FRONTAL BOUNDARY WILL CONTINUE TO WORK ITS WAY SOUTHEAST ACROSS THE
CWA THIS AFTERNOON AND EVENING. MAIN FORECAST ISSUE TONIGHT INTO
TOMORROW WILL BE CLOUD COVER AND TEMPERATURES. STRATUS DECK
ASSOCIATED WITH THE LOW LEVEL COLD AIR ADVECTION PUSH IS CURRENTLY
MOVING SOUTH INTO NORTHERN SOUTH DAKOTA. MODELS HANDLE THIS FEATURE
DIFFERENTLY. LOOKS LIKE THE NAM IS DECOUPLING THE BOUNDARY LAYER TOO
MUCH TONIGHT...WHICH ACTS TO KEEP THE STRATUS AT BAY. FEEL LIKE
SOMETHING CLOSER TO THE RAP SOLUTION IS MOST LIKELY...WHERE THE COLD
AIR ADVECTION KEEPS THE BOUNDARY LAYER MIXED ENOUGH TO KEEP THE
STRATUS LOCKED IN AND SPREADING SOUTH. COULD EVEN SEE SOME SPOTTY
DRIZZLE IN THE EASTERLY UPSLOPE LOCATIONS OF SOUTHWEST MINNESOTA.
THUS WILL LEAN TOWARDS THIS SOLUTION WITH CLOUDS INCREASING FROM
NORTH TO SOUTH TONIGHT. LOWS MAINLY IN THE 30S...WITH THE CLOUDS AND
BREEZE PREVENTING TEMPS FROM FALLING TOO FAR.
ON FRIDAY...LOW STRATUS WILL BEGIN TO ERODE FROM SOUTH TO NORTH.
HOWEVER AT THE SAME TIME...SOUTHEASTERLY WINDS WILL ADVECT IN
ADDITIONAL MOISTURE AROUND 850 MB...ALLOWING ANOTHER STRATUS DECK TO
QUICKLY FORM. THUS THINK MUCH OF THE AREA STAYS CLOUDY THROUGH THE
DAY...WITH SOUTHERN AREAS HAVING THE BEST CHANCE OF SEEING A BIT OF
MORNING SUN. MOISTURE WILL CONTINUE TO DEEPEN THROUGH THE DAY...WITH
PORTIONS OF SOUTHWEST MINNESOTA AND NORTHWEST IOWA POSSIBLY SEEING
SOME DRIZZLE BY MID AFTERNOON AS WE SEE WEAK LIFT IN THE NEARLY
SATURATED 0-1 KM LAYER. FORECAST CONFIDENCE IS OVERALL PRETTY LOW ON
FRIDAY. THE NAM IS A LOT SLOWER THAN THE GFS WITH STRATUS
FORMATION...WITH THE GFS THE FASTEST. THE FORECAST FOLLOWS CLOSEST
TO THE GFS SOLUTION...WHICH APPEARS TO BE HANDLING THINGS BEST AT
THE CURRENT TIME. THUS WITH THE CLOUDS AROUND...LOWERED HIGHS A FEW
DEGREES FOR TOMORROW...GENERALLY MID TO UPPER 40S NORTH TO MID 50S
SOUTHEAST. IF A SOLUTION CLOSER TO THE NAM PANS OUT RESULTING IN A
LONGER PERIOD OF SUN...HIGHS WILL BE A GOOD 5 DEGREES WARMER...AND
IF THE CLOUDS STAY LOCKED IN EVEN MORE THAN EXPECTED...HIGHS WOULD
BE A FEW DEGREES COOLER THAN CURRENT FORECAST. /CHENARD
COMPLICATED FORECAST ANTICIPATED FOR THE WEEKEND WITH THE WELL
ADVERTISED SURFACE LOW AND BROAD SURFACE TROUGH TRACKING THROUGH THE
AREA. FOR FRIDAY NIGHT...LOW STRATUS WILL REMAIN A CONCERN WITH ALL
MODELS KEEPING A LOW CLOUD DECK IN PLACE OVERNIGHT. THE GFS AND
ECMWF CONTINUE TO INDICATE A DEEPER MOIST LAYER THAN THE NAM...WHICH
POINTS TO A GREATER POTENTIAL FOR LIGHT FOG/MIST INSTEAD. HAVE
OPTED TO FOLLOW THE GFS/ECMWF AND THE POTENTIAL FOR SOME DRIZZLE OR
VERY LIGHT RAIN POSSIBLE IN OUR NORTHEAST CORNER OVERNIGHT. LOWER
VISIBILITIES OR MIST WOULD BE REASONABLE IN THIS AREA AS WELL...BUT
DO NOT THINK THE FOG WILL BE DENSE ENOUGH TO MENTION IN THE GRIDS.
TEMPERATURES WILL BE QUITE MILD OVERNIGHT IN THE 40S.
SATURDAY HAS THE POTENTIAL FOR BEING A VERY MILD DAY...PARTICULARLY
ACROSS OUR EASTERN HALF. THE SURFACE LOW GRADUALLY LIFTS NORTH
NORTHEAST THROUGH THE CENTER OF THE CWA INTO SOUTHWEST MINNESOTA.
IT DOES LOOK LIKE THE STRATUS WILL BEGIN TO BREAK EARLY IN THE DAY
ACROSS OUR EAST AS THE WARM FRONT LIFTS NORTH AND SOUTHERLY FLOW
TAKES OVER. COULD SEE SOME WEAK MID LEVEL INSTABILITY IN THIS WARM
SECTOR IN THE AFTERNOON AND EVENING ACROSS NORTHWEST IOWA WHICH
WOULD BRING AN ISOLATED THREAT FOR SOME THUNDERSTORMS IN ADDITION TO
THE RAIN SHOWERS WHICH SHOULD BEGIN WORKING INTO THE AREA. THE COLD
FRONT FINALLY KICKS THROUGH OUR EASTERN HALF BY LATE SATURDAY
EVENING...WITH THE STRATIFORM PRECIPITATION SPREADING THROUGH THE
REMAINDER OF THE FORECAST AREA BEHIND IT. MUCH COLDER AIR WILL
QUICKLY ARRIVE OVERNIGHT...TRANSITIONING THE RAIN TO A MIX AND THEN
ENTIRELY SNOW BY DAYBREAK.
FOR EARLY SUNDAY...THE LINGERING MID LEVEL EXITS TO OUR EAST WITH
COOLER AND DRIER AIR WORKING INTO THE REGION. THE NAM IS THE FASTEST
IN EXITING THE WAVE WITH THE BULK OF THE EVENT OVER LATE SUNDAY
NIGHT...WHILE THE GFS AND ECMWF SUGGEST A LINGERING BAND OF LIGHT
SNOW OVER THE FORECAST AREA INTO MID DAY. THE BULK OF THE SNOW WILL
BE OVER AT THIS POINT...BUT HAVE HELD ONTO A CHANCE FOR THE MORNING.
THE HIGHEST SNOWFALL AMOUNTS ARE EXPECTED WEST OF THE JAMES RIVER
WHERE 2 TO 3 INCHES ARE EXPECTED...WHILE NORTHWEST IOWA CAN EXPECT A
HALF INCH OR LESS. VERY BRISK NORTHWEST WINDS WILL COMBINE WITH
HIGHS ONLY TOPPING OUT IN THE MID 20S TO MID 30S.
IN THE EXTENDED...QUIETER WEATHER IS ON TAP EARLY NEXT WEEK INTO MID
WEEK AS THE PATTERN TRANSITIONS INTO A MORE ZONAL FLOW. HIGHS ON
MONDAY WILL REMAIN COLD IN THE UPPER 20S TO LOWER 30S...THEN
GRADUALLY MODERATE INTO THE 40S BY MID WEEK. DID DROP LOWS A FEW
DEGREES BELOW THE ALLBLEND ON SUNDAY NIGHT...BUT SOME LINGERING
WINDS WOULD LIKELY PREVENT TEMPERATURES FROM REALLY DROPPING OFF.
LOWS WILL BE IN THE TEENS SUNDAY NIGHT AND MONDAY NIGHT.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
905 PM CST SAT NOV 10 2012
.UPDATE...
NO CHANGES.
&&
.DISCUSSION...
SURFACE TROUGH AND COLD FRONT EXTENDED FROM WINK NORTHEAST TO
LUBBOCK...THEN INTO NW OKLAHOMA. SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS HAD DEVELOPED EAST OF THE FRONT IN THE PERMIAN
BASIN AND SE TEXAS PANHANDLE.
SCATTERED SHOWERS STILL EXPECTED TO MOVE INTO EASTERN SECTIONS OF
WEST CENTRAL TEXAS AFTER MIDNIGHT...AS UPPER TROUGH IN THE ROCKY
MOUNTAINS MOVES EAST. RUC MUCAPES ON SPC MESOSCALE ANALYSIS PAGE
FOR WEST CENTRAL TEXAS...WERE ON THE LOWER SIDE FOR SEVERE
STORMS...IN THE 500 TO 800 J/KG RANGE...BUT 0-6 KM SHEAR WAS
QUITE HIGH AT OVER 50 KTS. THUS WHILE A STRONG STORM OR EVEN
SEVERE STORM POSSIBLE...MOST SHOULD REMAIN BELOW SEVERE LIMITS.
MAIN POTENTIAL FOR SEVERE WEATHER TONIGHT...MAY BE DAMAGING WINDS
...IF THE STRONG WINDS ASSOCIATED WITH THE 50-60 KT LOW LEVEL JET
PARTIALLY MIX TO GROUND LEVEL WITH PRECIPITATION.
FORECAST LOOKS TO BE IN GOOD SHAPE...THUS WILL NOT MAKE CHANGES
AT THIS TIME.
&&
.PREV DISCUSSION... /ISSUED 520 PM CST SAT NOV 10 2012/
UPDATE...
SEE 00Z AVIATION DISCUSSION BELOW.
AVIATION...
VFR CONDITIONS TO PREVAIL THE MAJORITY OF THE TIME ACROSS WEST
CENTRAL TEXAS TERMINALS. STARTING TO SEE A FEW SHOWERS DEVELOP
ACROSS THE SOUTH PLAINS...AND THESE SHOULD GRADUALLY MOVE EAST AND
INCREASE IN COVERAGE SOME THROUGH THE OVERNIGHT HOURS. BETTER
CHANCES ACROSS THE BIG COUNTRY...WITH THE ABILENE...KABI...
TERMINAL THE MOST LIKELY TO SEE ONE OF THESE STORMS.
STILL...TIMING AND COVERAGE REMAINS A QUESTION...SO WILL NOT
INCLUDE ANYTHING MORE THAN A VCTS.
OTHERWISE...BREEZE SOUTH WINDS TO CONTINUE OVERNIGHT...AND WILL
LIKELY SEE A FEW STRATUS...BUT MAY ACTUALLY HAVE A HARD TIME
FORMING ANYTHING MORE THAN A BRIEF CIG. COLD FRONT MOVES QUICKLY
THROUGH ON SUNDAY...BRINGING DRIER CONDITIONS ON STRONG WEST WINDS.
PREV DISCUSSION... /ISSUED 359 PM CST SAT NOV 10 2012/
SHORT TERM...
UPPER LEVEL TROUGH MOVING ACROSS THE ROCKIES THIS AFTERNOON...WITH
MODELS SHOWING THE BEST SYNOPTIC LIFT MOVING ACROSS THE BIG COUNTRY
NORTHWARD INTO OKLAHOMA AND KANSAS LATER THIS EVENING. MAIN SURFACE
LOW WELL NORTH...BUT DRYLINE HAS TRIED TO BECOME ESTABLISHED SOUTH
THROUGH MUCH OF WEST TEXAS. ATMOSPHERE HAS BEEN CAPPED SO FAR AHEAD
OF THIS DRYLINE...BUT APPROACHING LIFT SHOULD BE ABLE TO ERODE THIS
CAP THIS EVENING. STILL LOOKS LIKE MOST OF THE CONVECTION WILL BE
FARTHER NORTH...WITH THE TAIL END ACROSS THE BIG COUNTRY AND PERHAPS
AS FAR SOUTH AS THE CONCHO VALLEY. ONCE STORMS DEVELOP...SHOULD
SOLIDIFY INTO A MORE SOLID AREA AS LOW LEVEL JET OF 50 KNOTS
DEVELOPS.
PACIFIC FRONT OVERTAKES THE DRYLINE AND PUSHES QUICKLY ACROSS WEST
CENTRAL TEXAS BETWEEN 12Z AND 18Z ON SUNDAY. WILL CONTINUE THE
CHANCE OF STORMS THROUGH THE MORNING HOURS WITH CONVECTION STILL
LIKELY ONGOING ACROSS THE AREA...WITH A MUCH DRIER AIR MASS
FOLLOWING THE FRONT FOR THE AFTERNOON. BREEZY WEST WINDS...WHICH ARE A
DOWNSLOPE...WILL OFFSET A LITTLE OF THE COLD ADVECTION...AND WILL
KEEP TEMPERATURES ON THE WARM SIDE OF GUIDANCE.
FIRE WEATHER CONCERNS WILL ALSO NEED TO BE MONITORED SUNDAY
AFTERNOON...AS HUMIDITY AND WIND CONDITIONS MAY APPROACH RED FLAG
CRITERIA. HOWEVER...RECENT RAINFALL HAS ACTUALLY ALLOWED FOR A
LITTLE BETTER VEGETATION. NEXT SHIFT WILL NEED TO MONITOR...BUT WILL
HOLD OFF ON ANY HIGHLIGHTS FOR NOW.
07
FOR THE REMAINDER OF THE SHORT TERM...THROUGH TUESDAY...LOOK FOR
UNSEASONABLY COLD TEMPERATURES. THE NAM AND GFS ARE IN VERY GOOD
AGREEMENT THIS CYCLE. OVERNIGHT TOMORROW NIGHT...TEMPERATURES AT
850 MB WILL RANGE FROM AROUND 2 CELSIUS ACROSS THE NORTHERN BIG
COUNTRY TO AROUND 5 CELSIUS AROUND OUR SOUTHERN COUNTIES.
PLUS...SURFACE WINDS TOMORROW NIGHT WILL BE VERY LIGHT TO PERHAPS
CALM...AS SURFACE HIGH PRESSURE DOMINATES TEXAS. THESE TWO
FACTORS...ALONG WITH CLEAR SKIES AND ASSOCIATED RADIATIONAL
COOLING...WILL PRODUCE LOWS SUNDAY NIGHT AROUND 30. DURING THE
DAY MONDAY...THE SURFACE HIGH WILL SLIDE EAST...AND SOUTHERLY
SURFACE RETURN FLOW WILL DEVELOP. HOWEVER...850 MB TEMPERATURES DO
NOT REBOUND MUCH DURING THE DAY. THUS...AFTERNOON HIGHS MAINLY IN
THE 55 TO 60 RANGE AND WELL BELOW SEASONAL NORMALS LOOK LIKELY.
OVERNIGHT MONDAY NIGHT...RADIATIONAL COOLING AND LIGHT WINDS WILL
AGAIN PRODUCE LOWS BELOW THE FREEZING MARK...WITH SOME AREAS
LIKELY FALLING INTO THE MID 20S HARD-FREEZE RANGE. FOR
TUESDAY...850 MB TEMPERATURES BEGIN TO REBOUND SLIGHTLY. WITH LOTS
OF SUNSHINE TUESDAY...I EXPECT AFTERNOON HIGHS VERY CLOSE TO MEX MOS
GUIDANCE NUMBERS...MAINLY IN THE 60 TO 65 RANGE.
HUBER
LONG TERM...
TEMPERATURES CONTINUE A SLOW REBOUND INTO THE START OF NEXT
WEEKEND. ALOFT...THE PATTERN SHIFTS FROM A BROAD RIDGE TO MAINLY
ZONAL FLOW. AT THE SURFACE...SOUTHERLY FLOW DOMINATES THE BOUNDARY
LAYER...AND SURFACE DEWPOINT TEMPERATURES RETURN TO THE MID TO
UPPER 50S BY FRIDAY AFTERNOON. TEMPERATURE NUMBERS CLOSE TO MEX
MOS GUIDANCE LOOK GOOD...WITH AFTERNOON HIGHS WELL ABOVE SEASONAL
NORMALS FOR SATURDAY.
HUBER
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 58 70 31 54 29 / 30 20 5 5 0
SAN ANGELO 59 71 31 58 29 / 20 20 5 5 0
JUNCTION 61 75 29 61 28 / 10 30 5 5 0
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/04
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1127 AM PST Fri Nov 9 2012
.SYNOPSIS...
A slow moving low pressure area will continue to meander slowly
over the northeast corner of Washington which will result in more
light snow for the northern Idaho Panhandle and much of northeast
and north central Washington. The low will weaken overnight and be
replaced by weak ridging for the weekend. This will result in a
gradual drying trend...but cold temperatures will continue. Wet
and snowy weather is expected to return to the region by the
beginning of the next work week.
&&
.DISCUSSION...
Morning Update: Steady light snow with embedded heavier showers
continue along the northeastern periphery of a 700mb low. HRRR is
handling the current situation well and was generally referenced
for the remainder of the afternoon. Consequently, the main axis of
light snow will stretch from Lookout Pass...northwest to Sherman
Pass and this is where we will continue the snow advisory for now
with the main travel impacts being along roads that climb near
3000 feet or higher. This does not mean the valleys will escape
with no impacts but snow accumulations on roads will be confined
to isolated heavier showers. Meanwhile, drier, continental air
moving down the Purcell Trench continues to work against the snow
processes aloft and has resulted in little to no snow from
Sandpoint northward. All things considered, we have trimmed
several areas from the snow advisory including the Bonners Ferry
area, Spokane-CDA, and valleys west of Colville. Given the persistent
and heavier shower activity from Deer Park Chewelah, we left this
section of Hwy 395 in the advisory. See the "Detailed Hazard" tab.
South of the main low, sunbreaks have lead to increasing
instability and light showers will be possible just about
anywhere. We are not real concerned with snow accumulations with
this activity given the warmer surface temperatures. We will have
to keep a close eye on activity for the Blue Mtns and Camas
Prairie where orographic flow is a bit more northwesterly. /sb
&&
.AVIATION...
18Z TAFS: Steady snow and snow showers will continue along and
north of a line from COE-GEG. We do not expect additional
accumulations away from grassy surfaces. IFR cigs will trend MVFR
as drier air works in from the northeast. This will lead to breezy
winds down the Purcell Trench from COE-SZT with gusts to 30 mph.
Elewhere, sunbreaks will promote hit or miss light snow showers.
Under these showers, expect brief MVFR to locally IFR conditions.
Stratus will be the more dominate nuisance overnight frm Spokane
to CDA given the weak NE push but a combination of fog and stratus
will be possible at the remaining terminals and carry low
confidence. The system driving the snow today will weaken this
evening and overnight period and we expect most snow showers to
be over by early Saturday. /sb
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 36 19 30 16 33 25 / 50 30 0 0 10 30
Coeur d`Alene 35 18 30 14 34 24 / 90 40 10 0 10 20
Pullman 35 22 31 18 34 24 / 20 20 10 0 0 20
Lewiston 41 27 35 22 38 30 / 20 10 10 0 0 20
Colville 37 22 33 17 36 25 / 90 40 0 0 10 30
Sandpoint 35 19 29 11 33 21 / 90 30 0 0 10 10
Kellogg 34 20 27 15 30 22 / 90 70 10 0 0 0
Moses Lake 43 22 36 20 38 27 / 10 0 0 0 0 50
Wenatchee 43 28 37 23 37 29 / 20 10 10 0 0 50
Omak 42 24 36 21 37 27 / 10 10 0 0 10 40
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Weather Advisory until 4 PM PST this afternoon for
Central Panhandle Mountains-Northern Panhandle.
WA...Winter Weather Advisory until 4 PM PST this afternoon for
Northeast Mountains-Okanogan Highlands.
&&
$$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1015 PM PST Thu Nov 8 2012
.SYNOPSIS...
The weather pattern in the Pacific Northwest will become more
active tonight when the first of a number of winter weather systems
impacts the region and exits early Saturday Morning. The remainder
of the weekend may remain precipitation free until yet another low
pressure system passage brings snow and rain to the region Monday
and Tuesday.
&&
.DISCUSSION...
Update: We`ve been tracking low pressure and the band of precipitation
wrapping around it. Across much of northeast third of Washington
and the Idaho Panhandle, from the higher Palouse through much of
the Spokane area and northern Mountains eastward, temperatures
have been cold enough to support snow or at least a rain/snow mix.
On the West Plains, near our office, we picked up around 0.7
inches of snow on our snowboard since about 4 pm this afternoon.
The center of the developing low is best analyzed around 700mb and,
using IR satellite and RUC guidance, it has been tracking north-
northeast toward the Spokane/Whitman county border. A deformation
axis/700mb theta-e axis wrapped has been lifting in with it and at
of about 03Z (7PM) it wrapped from the central Panhandle, north
and west to near the eastern I-90 corridor. Lift from the
deepening low and parent upper trough, along with the deformation
axis has been helping to focus moisture and the resultant
precipitation. At the same time, more widely scattered showers are
found on its backside around the Basin. A bit of a dry slot is
coming up from the south, drying out part of the lower Palouse.
The short-range models continue to track to low and the
accompanying deformation axis (which will continue to provide a
focus for precipitation) northward. Guidance suggests the primary
core of the precipitation starting to shift north of the I-90
corridor going through the overnight into Friday morning. This
trend seems valid. Through Friday the deformation axis weakens
near the foothills of the Selkirks/Long Lake area and gradually
starts to track east-southeast by late Friday.
Given this depicted trend and recalling previous events, oftentimes
the deformation axis/boundary stalls and provides more focused
band of precipitation within the broader precipitation shield north
of I-90, from the base of the Selkirk into areas near and north of
Coeur d`Alene. Given this thinking and the fact thus far models
seem to have underdone the precipitation amounts I went ahead and
raised QPF and accompanying snow amounts slightly. This does not
change the overall highlights in effect, but some areas could see
localized amounts near or over 6 inches. This is primarily focused
across areas along and north of a line from Wellpinit to Colbert
to Hayden and the Rathdrum Prairie. /J. Cote`
&&
.AVIATION...
06Z TAFS: Low pressure will continue to deepen over eastern WA
tonight before slowly weakening Friday and edging east.
Moisture and cold air wrapped in it will continue to provide
areas of snow, occasionally mixed with rain near the southern
TAF sites. IFR cigs and vis will be most persistent around KGEG to
KCOE (and areas north), while VFR/MVFR conditions will be more
prevalent elsewhere. The precipitation is expected dissipate
around the TAF sites through the late morning to afternoon Friday,
with cigs and vis improving toward MVFR and eventually toward VFR
by late day; however watch for lowering cigs again late Friday
night (into Saturday morning). /J. Cote`
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 28 33 19 31 19 33 / 100 80 20 0 0 10
Coeur d`Alene 29 33 16 30 17 34 / 100 90 30 10 0 10
Pullman 29 33 20 31 18 34 / 80 80 30 10 10 0
Lewiston 33 38 24 35 22 38 / 70 60 20 10 0 0
Colville 28 37 20 35 20 36 / 100 80 10 0 0 10
Sandpoint 26 31 14 29 16 34 / 100 90 20 0 0 10
Kellogg 28 30 17 26 17 30 / 100 100 60 10 0 0
Moses Lake 29 41 22 38 21 38 / 20 20 10 0 0 0
Wenatchee 32 40 24 38 23 38 / 20 20 10 10 0 0
Omak 30 39 22 37 20 38 / 20 30 10 0 0 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Weather Advisory until 4 PM PST Friday for Central
Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
Northern Panhandle.
Winter Weather Advisory until 4 PM PST Friday for Lewis and
Southern Nez Perce Counties.
WA...Winter Weather Advisory until 4 PM PST Friday for Northeast
Mountains-Okanogan Highlands-Spokane Area-Washington
Palouse.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
531 PM CST SAT NOV 10 2012
.SHORT TERM...TONIGHT THROUGH TUESDAY
332 PM CST SAT NOV 10 2012
AT 3 PM...A WARM FRONT WAS LOCATED JUST NORTH OF THE INTERSTATE 94
CORRIDOR. SOUTH OF THIS FRONT...TEMPERATURES WERE IN THE 60S AND
70S. RECORD HIGH TEMPERATURE WERE SET AT BOTH LA CROSSE WI /68F -
PREVIOUS RECORD 67 IN 2010/ AND ROCHESTER MN /72F - PREVIOUS
RECORD 68F IN 1949/. THERE WILL LIKELY BE A FEW COOPERATIVE
RECORDS SET TOO...BUT WE WILL HAVE TO WAIT UNTIL 7 AM SUNDAY TO
KNOW WHICH SITES ESTABLISHED OR TIED RECORDS. NORTH OF THIS
FRONT...THE TEMPERATURES WERE IN THE 40S AND 50S.
FOR THIS EVENING...A SHORT WAVE TROUGH WILL MOVE NORTHEAST THROUGH
THE REGION. SOUNDINGS SHOW THAT THE MOISTURE ASSOCIATED WITH THIS
WAVE WILL BE MAINLY ABOVE 650 MB. WITH STEEP LAPSE RATES /NEARLY 9
C/KM / AND THE ELEVATED CAPE RUNS BETWEEN 100 AND 200 J/KG...ONLY
WENT WITH SOME SCATTERED SPRINKLES WITH THIS SYSTEM. IN
ADDITION...IF THE TEMPERATURES DO NOT COOL AS FAST AS EXPECTED...
THERE WILL BE THE POTENTIAL FOR SOME WIND GUSTS TO CLIMB INTO THE
30 TO 40 MPH RANGE.
OVERNIGHT...THE RAIN CHANCES WILL GRADUALLY INCREASE FROM WEST TO
EAST AS A LONG WAVE TROUGH APPROACHES THE AREA. IN ADDITION...WITH
ELEVATED CAPES UP TO 200 J/KG AND INCREASING FRONTOGENESIS...THERE
WILL BE A POTENTIAL OF A FEW THUNDERSTORMS. WHILE THE 0-6 KM SHEAR
IS FAVORABLE FOR MINI SUPERCELLS...THE 1-6 KM SHEAR IS NOT
FAVORABLE AT ALL. AS A RESULT...NOT EXPECTING ANY SEVERE WEATHER.
HOWEVER WITH THE STRONG WINDS ALOFT COULD NOT RULE OUT AN ISOLATED
WIND GUST IN THE 35 TO 45 MPH RANGE OCCURRING WITH EITHER A SHOWER
OR THUNDERSTORM.
FROM SUNDAY THROUGH SUNDAY EVENING...THE LONG WAVE TROUGH WILL MOVE
EAST ACROSS THE AREA. THE COMBINATION OF SUBTROPICAL MOISTURE
/PRECIPITABLE WATER VALUES 250 TO 300 PERCENT OF NORMAL OR 1.00 TO
1.25 INCHES/...WARM CLOUD LAYER DEPTHS UP TO 3 KM...AND RIGHT
ENTRANCE REGION OF THE UPPER LEVEL JET WILL RESULT IN SOME HEAVY
RAIN FROM TIME TO TIME. RAINFALL TOTALS WILL LIKELY RANGE FROM
0.50 TO 1.50 INCHES. THE HEAVIEST RAIN WILL BE EAST OF A ZUMBROTA
MINNESOTA TO OELWEIN IOWA LINE. TEMPERATURES BEHIND THE COLD FRONT
WILL DROP INTO THE 30S. THIS WILL ALLOW THE RAIN TO CHANGE OVER TO
EITHER A RAIN/SNOW MIX OR SNOW PRIOR TO ITS ENDING. WHILE THERE
MAY BE SOME LIGHT DUSTINGS OF SNOW...MOST LOCATIONS WILL SEE NO
SNOW ACCUMULATIONS FROM THIS SYSTEM.
ON MONDAY...ANOTHER SHORT WAVE TROUGH WILL MOVE SOUTHEAST THROUGH
THE AREA. 950 TO 800 LAPSE RATES ARE AROUND 9 C/KM AND CAPES ARE
UP 50 J/KG...AS A RESULT THERE MAY BE SOME SCATTERED SNOW SHOWERS
AND FLURRIES.
.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY
332 PM CST SAT NOV 10 2012
ON TUESDAY NIGHT AND WEDNESDAY...THE 10.12Z MODELS ARE IN GOOD
AGREEMENT THAT A SHORT WAVE TROUGH WILL MOVE EAST THROUGH THE
AREA. WHILE THERE IS MODERATE 280 TO 290K ISENTROPIC LIFT...THE
CONDENSATION PRESSURE DEFICITS REMAIN ABOVE 50 MB. IN
ADDITION...BUFKIT SOUNDINGS CONTINUE TO SHOW DRY AIR BELOW
750 MB. AS A RESULT...KEPT THE FORECAST DRY FOR THIS TIME PERIOD.
ON THURSDAY AFTERNOON AND NIGHT...ANOTHER SHORT WAVE TROUGH MOVES
EAST THROUGH THE REGION. LIKE ITS PREDECESSOR...MUCH OF THE LIFT
ASSOCIATED WITH THIS WAVE GOES INTO SATURATING THE AIR MASS ABOVE
775 MB AND THE 280-290K CONDENSATION PRESSURE DEFICITS ARE ONLY
ABLE TO DROP TO 50 MB...THUS...KEPT THIS PERIOD DRY.
FOR FRIDAY NIGHT AND SATURDAY...THERE CONTINUES TO BE LITTLE RUN TO
RUN CONSISTENCY BETWEEN THE 12Z AND 00Z MODELS. THE 00Z RUNS SHOW
PRECIPITATION OCCURRING ON DAY 7. MEANWHILE THE 12Z RUNS HAVE BEEN
DRY. MUCH OF THIS HAS TO DUE WITH WHETHER A NEGATIVE NORTH
ATLANTIC OSCILLATION DEVELOPS. WITH THE MODELS CONTINUING TO DELAY
THE ONSET OF THIS PRECIPITATION...KEPT THIS PERIOD DRY TOO.
&&
.AVIATION...TONIGHT AND SUNDAY
531 PM CST SAT NOV 10 2012
TAF SITES CURRENTLY IN THE WARM SECTOR WITH SOUTHERLY WINDS AND
JUST SOME MID AND HIGH LEVEL CLOUDS. EXPECT THESE CONDITIONS TO
CONTINUE THROUGH ABOUT 10Z BEFORE CEILINGS BEGIN TO LOWER AHEAD OF
THE APPROACHING COLD FRONT. WITH THE STRONG PRESSURE GRADIENT IN
PLACE...BOTH THE 10.18Z NAM AND 10.21Z RAP BUFKIT SOUNDINGS SHOW
50 TO 60 KNOT WINDS AROUND 2000 FEET AND THUS CONTINUED TO MENTION
LLWS AT BOTH SITES BETWEEN 02Z-14Z. AFTER 10Z TONIGHT...EXPECT
CEILINGS AND VISIBILITIES TO LOWER AS PRECIPITATION BREAKS OUT
AHEAD OF THE FRONT. CEILINGS LOOK TO LOWER INTO THE IFR CATEGORY
AND REMAIN THERE TOUGH MUCH OF THE REMAINING TAF PERIOD. THE COLD
FRONT WILL PUSH THROUGH KRST BETWEEN 15Z-18Z AND KLSE 18Z-20Z.
MUCH COLDER AIR WILL PUSH IN BEHIND IT WITH ANY REMAINING
PRECIPITATION BECOMING MIXED WITH AND POSSIBLY CHANGING TO ALL
SNOW.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
332 PM CST SAT NOV 10 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
253 PM CST FRI NOV 9 2012
.SHORT TERM...TONIGHT AND SATURDAY.
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW SURFACE LOW
PRESSURE EMERGING INTO THE CENTRAL GREAT PLAINS AND A WARM FRONT
SNAKING ITS WAY ACROSS KANSAS...NORTHERN MISSOURI...AND CENTRAL
ILLINOIS. AN 850MB DEFORMATION ZONE EXISTS OVER NORTHERN WISCONSIN
EARLY THIS AFTERNOON...AND THE CONVERGENCE IS HELPING TO CREATE
WIDESPREAD CLOUD COVER. SCT SHOWERS DEVELOPED EARLIER TODAY OVER
CENTRAL LAKE MICHIGAN ON THE NOSE OF A WEAK LOW LEVEL JET BUT THEY
HAVE SINCE MOVED ON INTO LOWER MICHIGAN. AS THE WARM FRONT LIFTS
NORTH TONIGHT AND SATURDAY...PRECIP AND THUNDER CHANCES ARE THE MAIN
FORECAST CONCERNS.
TONIGHT...AS HEIGHT FALLS OCCUR OVER THE WESTERN GREAT PLAINS WITH
THE APPROACH OF THE LARGE WESTERN CONUS TROUGH...WARM ADVECTION WILL
RAMP UP FROM THE NORTHERN MISSISSIPPI VALLEY TO THE EASTERN GREAT
LAKES TONIGHT. CURRENT LLJ OVER SOUTHERN LAKE MICHIGAN/SE LOWER
MICHIGAN AND ILLINOIS WILL BYPASS THE STATE AS IT SHIFTS TO THE
SOUTHEAST THIS EVENING. WILL HAVE TO WAIT FOR A SECONDARY AND
STRONGER LLJ TO ORGANIZE OVER THE SOUTHERN MISSOURI VALLEY AND LIFT
NORTHWARD LATE THIS EVENING FOR OUR MEANINGFUL PRECIP CHANCES TO
ARRIVE. OPERATIONAL MODELS THIS MORNING ARE DELAYING PRECIP CHANCES
AS IT LOOKS LIKE WEAK ISENTROPIC ASCENT THIS EVENING WILL GO TOWARDS
TRYING TO SATURATE THE COLUMN. HAVE TRIMMED POPS ACROSS THE NORTH
AS A RESULT. STRONGER ISENTROPIC ASCENT AND MOISTURE TRANSPORT THEN
ARRIVES AFTER MIDNIGHT AND HAVE INCREASED POPS TO LIKELY EVERYWHERE
EXCEPT NEAR THE U.P. BORDER. SHOULD ALSO SEE AREAS OF FOG DEVELOP
ONCE THE RAIN ARRIVES AS WELL. LOOKED AT THUNDER CHANCES TONIGHT
AND BUFKIT SOUNDINGS SHOW MID-LEVEL CAPPING AROUND 8KFT SO WILL KEEP
THUNDER OUT OF THE FORECAST. LOWS WILL STAY MILD AND RANGE FROM THE
MID 30S NORTH TO MID 40 SOUTHEAST.
SATURDAY...SURFACE LOW PRESSURE WILL TRACK NORTHEAST ACROSS THE
PLAINS INTO SOUTHERN MINNESOTA IN THE AFTERNOON. AHEAD OF THE
LOW...SW FLOW ALOFT WILL STRENGTHEN WHICH WILL INCREASE POP CHANCES
FOR THE MORNING INTO THE LIKELY/DEFINITE RANGE. AREAS OF FOG WILL
ALSO REMAIN AN ISSUE UNTIL DIURNAL HEATING CAN INCREASE THE
TEMPERATURE-DEWPOINT SPREAD BY LATE MORNING. MOST OF THE FORCING
SHOULD LIFT NORTH OF THE U.P. BORDER BY MID-AFTERNOON...WHICH SHOULD
END THE WIDESPREAD SHOWER THREAT. THE SURFACE WARM FRONT WILL LAG
BEHIND A BIT AND MOVE INTO CENTRAL WISCONSIN IN THE AFTERNOON.
TEMPS WILL BE THE WARMEST THERE...AND REACH INTO THE LOWER TO MIDDLE
60S. CAPPING ALSO DIMINISHES WITH THE APPROACH OF THE SURFACE WARM
FRONT...SO WILL LEAVE A MENTION OF ISOLATED THUNDER IN THE FORECAST.
.LONG TERM...SATURDAY NIGHT THROUGH NEXT FRIDAY. SHOWERS AND
ELEVATED THUNDERSTORMS POSSIBLE SATURDAY EVENING AS A WARM FRONT
MOVES INTO THE UPPER PENINSULA. THEN THERE WILL LIKELY BE LIGHHT
RAIN OR DRIZZLE LATE SATURDAY NIGHT AND SUNDAY ALONG WITH SOME
FOG. SURFACE WAVE MOVING NORTH ALONG A SLOW MOVING COLD FRONT
SHOULD PRODUCE A GOOD RAINFALL SUNDAY. THE RAIN WILL CHANGE TO
SNOW SUNDAY NIGHT OVER THE WESTERN PORTION OF THE FORECAST AREA
BUT ANY ACCUMULATIONS SHOULD BE LIGHT. BLUSTERY AND COLDER MONDAY
WITH CYCLONIC UPPER FLOW AND SCATTERED SNOW SHOWERS OR FLURRIES.
WINDS APPEAR TOO WESTERLY FOR LAKE EFFECT IN NORTHCENTRAL
WISCONSIN. DRY AND COOL TUESDAY THROUGH THURSDAY WITH UPPER FLOW
BECOMING ZONAL AND A SURFACE HIGH DRIFTING ACROSS THE AREA. SOME
CHANCE OF LIGHT PRECIPITATION TOWARDS THE END OF THE WEEK IN WARM
ADVECTION PATTERN BUT NOT MUCH MOISTURE SO LEFT IT DRY FRIDAY. &&
.AVIATION...SPOTTY MVFR CIGS OVER NORTHERN WISCONSIN WILL IMPROVE TO
VFR THIS AFTERNOON. THEN...A WARM FRONT WILL BE LIFTING NORTHWARD
ACROSS THE REGION LATE TONIGHT INTO SATURDAY. CIGS AND VSBYS WILL
BE FALLING MID-EVENING ONWARD AS LOW LEVEL MOISTURE INCREASES AHEAD
OF THIS FRONT. SHOWER/DRIZZLE CHANCES WILL ALSO IMPROVE THROUGH THE
NIGHT AS WELL. ONCE THE SHOWERS ARRIVE...CIGS AND VSBYS ARE
EXPECTED TO FALL INTO THE LIFR RANGE. SOME IMPROVEMENT EXPECTED BY
THE END OF THE TAF PERIOD AS SHOWERS LIFT OFF TO THE NORTHEAST.
MPC
&&
.MARINE...GUSTY SOUTH WINDS AND BUILDING WAVES MAY BE A HAZARD TO
SMALL CRAFT SATURDAY THROUGH EARLY SUNDAY. A COLD FRONT WILL MOVE
THROUGH SUNDAY AFTERNOON WITH GUSTY WEST WINDS AND LARGE WAVES
POSSIBLE FOLLOWING IT SUNDAY NIGHT AND MONDAY. &&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
RDM/MPC
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1218 PM MST FRI NOV 9 2012
.DISCUSSION...
IN A RECENT UPDATE HAVE ADDED SOUTHWEST CARBON COUNTY TO THE HIGH
WIND WARNING. KCOW HAS HAD GUSTS TO ABOVE 55 MPH SINCE 17Z. THE
WINDS AT KARL HAVE ALSO STARTED TO INCREASE...BUT GRADIENT MAY BE
TOO SOUTHERLY FOR THAT LOCATION FOR HIGH WINDS.
&&
.PREVIOUS DISCUSSION.../ISSUED AT 1105 AM MST FRI NOV 9 2012/...
.UPDATE...WINDS CONTINUE TO INCREASE OVER MAINLY THE WEST PART
OF THE CWA AT MID MORNING. AS OF 17Z...SOME LOCATIONS HAD
SUSTAINED WINDS BETWEEN 35 AND 40 MPH AND GUSTS BETWEEN 50 AND 55
MPH. THOSE PLACES INCLUDE KRWL AS WELL AS LOCATIONS ALONG OR NEAR
INTERSTATE 80 FROM KARL TO KRWL. WITH THE FAST MID LEVEL FLOW ABLE
TO MIX TODAY... WILL CONTINUE TO PREVIOUSLY ISSUED HIGH WIND
WARNING FOR THAT AREA.
THE OTHER CONCERN FOR THE REST OF THE DAY IS THE DURATION OF THE
LOW CLOUDS AND FOG OVER THE EAST PART OF THE CWA. SOUTHEAST WIND
FLOW AND WARMING TEMPERATURES IN THE MID LEVELS SHOULD COMBINE TO
KEEP THE LOW CLOUDS OVER MOST OF THAT AREA THROUGH THE EARLY
AFTERNOON. CLOUD BASES WILL SLOWLY LIFT OVER THAT TIME WITH
CLEARING ALREADY TAKING PLACE AT KIBM AND JUST OCCURRED AT KSNY.
THE SLOW IMPROVEMENT IS SHOWN ON THE LATEST HRRR AS WELL AS TIME
HEIGHT PLOTS FOR THOSE AREAS. FOG CONTINUES TO SLOWLY LIFT OVER
THAT AREA WITH THE VISIBILITIES NOW BETWEEN 3 AND 6 MILES. THE LOW
CLOUDS SHOULD KEEP HIGH TEMPERATURES LOWER THAN EXPECTED OVER THE
PANHANDLE. MEANWHILE...FURTHER WEST...TEMPERATURES ARE ALREADY
APPROACHING FORECAST HIGHS AND SO HAVE BUMPED UP AFTERNOON HIGHS IN
THOSE AREAS.
&&
.AVIATION...18Z TAFS. THROUGH 01Z...STRONG SOUTHWEST WINDS SUSTAINED
NEAR 40 KNOTS GUSTING TO 50 KNOTS AT RAWLINS. THROUGH 00Z...VFR
WITH SURFACE LOW STRENGTHENING ACROSS WESTERN WYOMING NEAR
THERMOPOLIS...PRODUCING INCREASING SOUTH AND SOUTHEAST WINDS ACROSS
TAF SITES. AFTER 00Z...SURFACE LOW DEVELOPING FROM NORTHEAST
COLORADO TO NORTH CENTRAL NEBRASKA WITH A COLD FRONT MOVING EASTWARD
AND STRETCHING FROM CHADRON TO FORT COLLINS BY 12Z SATURDAY.
AFTER 04Z...SCATTERED SNOW SHOWERS AND AREAS OF FOG AT RAWLINS
PRODUCING IFR AND MVFR AND MOUNTAIN OBSCUREMENT. VFR ELSEWHERE.
AFTER 15Z...WINDS BECOMING NORTH AND NORTHWEST AFTER COLD FRONTAL
PASSAGE AND INCREASING WITH WINDS GUSTING TO 30 KNOTS. SCATTERED
SHOW SHOWERS PRODUCING MVFR AT RAWLINS TAF WITH VFR AT OTHER
SITES. RUBIN
&&
.PREV DISCUSSION... /ISSUED 509 AM MST FRI NOV 9 2012/
SHORT TERM...TODAY THROUGH SUNDAY NIGHT...
MAIN FORECAST FOCUS WAS GIVEN TO THE HIGH WIND POTENTIAL ACROSS
PORTIONS OF CARBON COUNTY TODAY AND THE RETURN TO WINTRY WEATHER ON
SATURDAY.
BEFORE THEN...EARLY MORNING 11-3.9 FOG PRODUCT SHOWS THE EDGE OF
FOG/LOW STRATUS SLOWLY PROGRESSING WEST ALONG A LUSK TO BRIDGEPORT
LINE. MODELS DO NOT SUGGEST MUCH FURTHER MOVEMENT WEST OF THIS
FOG...SO FOR NOW HAVE KEPT IT EAST OF LUSK/SCOTTSBLUFF/SIDNEY.
ALTHOUGH...WILL NEED TO WATCH THIS CLOSELY THROUGH SUNRISE.
ATTENTION THEN TURNS TO THE UPSTREAM HIGH AMPLITUDE TROUGH THAT WILL
MOVE FROM THE WEST COAST TODAY INTO THE INTERMOUNTAIN WEST TONIGHT
AND SATURDAY. STRONG SOUTHWEST FLOW OUT AHEAD OF THIS TROUGH WILL
BECOME COUPLED TODAY AS THE MIXED LAYER DEEPENS. MEANWHILE...SFC
PRESSURE FALLS ACROSS CENTRAL WYOMING SHOULD FURTHER STRENGTHEN THE
LLVL GRADIENT LATER TODAY. ALTHOUGH AN ATYPICAL HIGH WIND
PATTERN...EXPECT TO SEE THE 50 TO 55 KNOTS OF WINDS AT THE TOP OF
THE MIXED LAYER BE REALIZED LATER THIS MORNING AND DURING THE
AFTERNOON HOURS. SO...HAVE WENT AHEAD AND UPGRADED TO A HIGH WIND
WARNING ACROSS MOST LOWER ELEVATIONS OF CARBON COUNTY TODAY. WINDS
WILL DECOUPLE THROUGH THE EVENING...SO EXPECT THE STRONGEST WINDS TO
SUBSIDE THEN. OTHERWISE EXPECT CLOUDS TO BE ON THE INCREASE FOR MOST
LOCATIONS THROUGH THE DAY AS PACIFIC MOISTURE STREAMS AHEAD OF THE
TROUGH. ONE MORE MILD DAY IN STORE TODAY...THE LIKES OF WHICH WE
WONT SEE AGAIN AT LEAST FOR THE NEXT 7 DAYS. UPSTREAM 00Z SOUNDINGS
HAVE A BROAD AREA OF 5C AT H7...SO EXPECT 50S AND LOW 60S FOR HIGHS
TODAY.
BY TONIGHT...SFC LOW WILL DEEPEN AS IT SLIDES SOUTHEAST ACROSS THE
CWFA. THIS WILL PULL THE COLD FRONT SOUTH INTO NRN ZONES BY AROUND
MIDNIGHT AND THROUGH THE REST OF THE CWFA SATURDAY MORNING.
INITIALLY..SNOW WILL DEVELOP AS A RESULT OF AROUND 40 KNOTS OF
MOIST H7 SOUTHWESTERLY FLOW INTO THE SNOWY/SIERRA MADRES LATE
THIS EVENING. AS THE SFC FRONT DEEPENS AND THE FAVORABLE LFQ OF H3
ARRIVES ON SATURDAY...WILL BEGIN TO SEE PRECIPITATION SPILL OUT
INTO LOWER ELEVATIONS. TEMPERATURES MAY BE WARM ENOUGH TO SEE A
PERIOD OF LIGHT RAIN INITIALLY...ESPECIALLY OVER THE SRN NE
PANHANDLE. HOWEVER CHANGE-OVER WILL OCCUR QUICKLY AS COLD AIR
FILTERS IN BEHIND THE COLD FROPA. WILL NEED TO WATCH THIS CLOSELY
AS ANY RAIN OUT AHEAD OF THE COLD FRONT MAY CREATE SLIPPERY
DRIVING CONDITIONS. THE BEST H7-H5 FRONTOGENESIS WILL BECOME
JUXTAPOSED WITH BEST JET SUPPORT ON SATURDAY AFTERNOON/EVENING
SUGGESTING THAT THE BEST SNOW POTENTIAL WILL OCCUR THEN. 00Z MODEL
OUTPUT CONTINUES TO TREND TOWARDS A SPLIT TROUGH SOLUTION WHICH
WILL LIMIT SNOWFALL POTENTIAL. ONLY TRENDED TOWARDS THIS DRIER
SOLUTION AND WILL AWAIT FURTHER CONFIRMATION FROM SUBSEQUENT RUNS.
STILL THINK THAT AN INCH OR TWO WILL CATCH MOST OF THE LOWER
ELEVATIONS...WITH PERHAPS UP TO 3 IN AREAS CLOSEST TO THE
MOUNTAINS. THE SNOWIES/SIERRA MADRES WILL FARE THE BEST WITH 6 TO
10 INCHES EXPECTED WITH HIGHER AMOUNTS POSSIBLE ALONG WEST FACING
SLOPES. SO...DID ISSUE A WINTER WEATHER ADVISORY FOR THAT AREA
BEGINNING AT 9 PM TONIGHT AND CONTINUING THROUGH MIDNIGHT SATURDAY
NIGHT. THE UPPER TROUGH WILL REMAIN OVER THE AREA ON
SUNDAY...WHICH SHOULD RESULT IN SOME RESIDUAL SNOW SHOWERS
ESPECIALLY OVER THE MOUNTAINS. OTHERWISE...EXPECT A GENERALLY DRY
DAY FOR SUNDAY.
THE OTHER MAJOR IMPACT FROM THIS SYSTEM WILL BE THE FRIGID AIR MASS
THAT WILL USHER IN THE COLDEST AIR THUS FAR THIS SEASON. H7
TEMPERATURES OF -14C TO -16C WILL PREVENT HIGH TEMPERATURES FROM
CLIMBING OUT OF THE 20S AT MOST LOCATIONS ON SUNDAY.
LIKEWISE...OVERNIGHT LOW TEMPERATURES WILL DIP INTO THE SINGLE
DIGITS AND TEENS FOR BOTH SATURDAY AND SUNDAY NIGHTS. WOULD NOT BE
AT ALL SURPRISED FOR SHELTERS VALLEYS WEST OF THE LARAMIE RANGE TO
FALL BELOW ZERO...ESPECIALLY ON SUNDAY NIGHT.
LONG TERM...MONDAY THROUGH FRIDAY...UPPER LEVEL WINDS WILL BACK TO
THE WEST ON MONDAY AS A BROAD RIDGE BUILDS OVER THE WESTERN CONUS
FOR MONDAY THROUGH WEDNESDAY. EXPECTING DRY CONDITIONS UNDER
PARTLY TO MOSTLY CLOUDY SKIES AS A MID/HIGH LEVEL CLOUD DECK
STREAMS OVERHEAD IN THIS ZONAL PATTERN. WINDS WILL REMAIN BREEZY
ALONG AND WEST OF THE LARAMIE RANGE THROUGH THIS TIME AS WELL WITH
THE RIDGE BUILDING IN FROM THE WEST. 700MB TEMPERATURES WILL
STEADILY CLIMB THROUGH THE WEEK BACK TO NEAR 0C BY WEDNESDAY...SO
EXPECTING HIGH TEMPS TO BECOME MORE NORMAL FOR THIS TIME OF YEAR
THROUGH THE WEEKEND. THE NEXT SYSTEM WILL MOVE ACROSS THE ROCKIES
THURSDAY NIGHT AND FRIDAY...DRAGGING A COLD FRONT THROUGH THE
FORECAST AREA EARLY FRIDAY MORNING. 00Z ECMWF IS QUITE A BIT
SLOWER THAN THE 00Z GFS...PREVIOUS RUNS...AND THE GFS ENSEMBLE
MEAN...SO WILL DISCOUNT THE 00Z ECMWF FOR THIS FORECAST. THE MAIN
UPPER TROUGH AXIS MOVES OVERHEAD 06Z FRIDAY WITH FLOW ALOFT
BECOMING SOUTHWEST AHEAD OF THE TROUGH. THE LEESIDE SFC TROUGH
WILL DEEPEN AHEAD OF THE UPPER TROUGH AS WELL WITH SOUTHEAST SFC
FLOW STRENGTHENING ACROSS THE EASTERN PLAINS ON THURSDAY. THE COLD
FRONT WILL MOVE EAST EARLY FRIDAY MORNING WITH SLIGHTLY COOLER
TEMPS EXPECTED FOR FRIDAY. MOIST SOUTHWEST FLOW AHEAD OF THE
TROUGH WILL BRING A SLIGHT CHANCE FOR RAIN/SNOW SHOWERS ALONG THE
WESTERN SLOPES OF THE MOUNTAINS BEGINNING THURSDAY AND CONTINUING
THE WEEKEND.
AVIATION...12Z TAF ISSUANCE...STRONG WEST TO SOUTHWEST WINDS ARE
EXPECTED TODAY ALONG AND WEST OF THE LARAMIE RANGE...WITH GUSTS
IN EXCESS OF 45 KTS EXPECTED FROM RAWLINS TO ARLINGTON. THESE WINDS
WILL EASE OVERNIGHT. ACROSS THE EAST...WIND WILL BE OUT OF THE
SOUTHEAST AT 10 TO 15 KTS...WITH IFR CIGS AND VSBYS ACROSS THE
NORTHERN PANHANDLE SITES THROUGH MIDMORNING. EXPECTING VFR THEN TO
RETURN FOR THE REMAINDER OF THE PERIOD IN THE EAST. A LOW PRESSURE
SYSTEM MOVING ACROSS THE REGION TONIGHT AND SATURDAY WILL BRING
SNOW TO THE MOUNTAINS LATE TONIGHT THROUGH TOMORROW...WITH SNOW
SPREADING INTO THE EASTERN PLAINS ON SATURDAY MORNING. LIKELY
TO SEE MVFR TO IFR DEVELOPING SATURDAY WITH OBSCURED MOUNTAINS.
FIRE WEATHER...ONE MORE MILD DAY IN STORE ACROSS THE DISTRICT
TODAY AS THE NEXT STORM SYSTEM BEARS DOWN ON THE REGION LATER
TONIGHT AND CONTINUING INTO THE WEEKEND. WINDY CONDITIONS WILL
DEVELOP TODAY ACROSS LOWER ELEVATIONS OF CARBON COUNTY WITH GUSTS
APPROACHING 60 MPH. THESE WILL SUBSIDE THIS EVENING AS A COLD
FRONT BEGINS TO WORK THROUGH. THIS FRONTAL SYSTEM WILL BRING SNOW
TO THE SNOWIES/SIERRA MADRES TONIGHT...SPILLING OUT ONTO THE
PLAINS ON SATURDAY. SNOWFALL AMOUNTS OF GENERALLY 1 TO 3 INCHES
WILL BE POSSIBLE ACROSS LOWER ELEVATIONS...WITH 6 TO 10 INCHES
ACROSS IN THE SNOWIES/SIERRA MADRES. SNOW WILL BEGIN TO WIND DOWN
LATE SATURDAY NIGHT...GIVING WAY TO MOSTLY DRY CONDITIONS ON
SUNDAY. TEMPERATURES WILL BECOME MUCH COLDER BEHIND THE COLD FRONT
HIGH TEMPERATURES ONLY CLIMBING INTO THE 30S ON SATURDAY...AND 20S
FOR SUNDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...HIGH WIND WARNING UNTIL 6 PM FRIDAY FOR WYZ104-WYZ109-WYZ110-
WYZ111.
WINTER WEATHER ADVISORY FROM 9 PM FRIDAY TO MIDNIGHT SUNDAY FOR
WYZ112-WYZ114.
NE...NONE.
&&
$$
UPDATE...WEILAND
SHORT TERM/FIRE WEATHER...HAHN
LONG TERM/AVIATION...RJM
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1105 AM MST FRI NOV 9 2012
.UPDATE...WINDS CONTINUE TO INCREASE OVER MAINLY THE WEST PART
OF THE CWA AT MID MORNING. AS OF 17Z...SOME LOCATIONS HAD
SUSTAINED WINDS BETWEEN 35 AND 40 MPH AND GUSTS BETWEEN 50 AND 55
MPH. THOSE PLACES INCLUDE KRWL AS WELL AS LOCATIONS ALONG OR NEAR
INTERSTATE 80 FROM KARL TO KRWL. WITH THE FAST MID LEVEL FLOW ABLE
TO MIX TODAY... WILL CONTINUE TO PREVIOUSLY ISSUED HIGH WIND
WARNING FOR THAT AREA.
THE OTHER CONCERN FOR THE REST OF THE DAY IS THE DURATION OF THE
LOW CLOUDS AND FOG OVER THE EAST PART OF THE CWA. SOUTHEAST WIND
FLOW AND WARMING TEMPERATURES IN THE MID LEVELS SHOULD COMBINE TO
KEEP THE LOW CLOUDS OVER MOST OF THAT AREA THROUGH THE EARLY
AFTERNOON. CLOUD BASES WILL SLOWLY LIFT OVER THAT TIME WITH
CLEARING ALREADY TAKING PLACE AT KIBM AND JUST OCCURRED AT KSNY.
THE SLOW IMPROVEMENT IS SHOWN ON THE LATEST HRRR AS WELL AS TIME
HEIGHT PLOTS FOR THOSE AREAS. FOG CONTINUES TO SLOWLY LIFT OVER
THAT AREA WITH THE VISIBILITIES NOW BETWEEN 3 AND 6 MILES. THE LOW
CLOUDS SHOULD KEEP HIGH TEMPERATURES LOWER THAN EXPECTED OVER THE
PANHANDLE. MEANWHILE...FURTHER WEST...TEMPERATURES ARE ALREADY
APPROACHING FORECAST HIGHS AND SO HAVE BUMPED UP AFTERNOON HIGHS IN
THOSE AREAS.
&&
.AVIATION...18Z TAFS. THROUGH 01Z...STRONG SOUTHWEST WINDS SUSTAINED
NEAR 40 KNOTS GUSTING TO 50 KNOTS AT RAWLINS. THROUGH 00Z...VFR
WITH SURFACE LOW STRENGTHENING ACROSS WESTERN WYOMING NEAR
THERMOPOLIS...PRODUCING INCREASING SOUTH AND SOUTHEAST WINDS ACROSS
TAF SITES. AFTER 00Z...SURFACE LOW DEVELOPING FROM NORTHEAST
COLORADO TO NORTH CENTRAL NEBRASKA WITH A COLD FRONT MOVING EASTWARD
AND STRETCHING FROM CHADRON TO FORT COLLINS BY 12Z SATURDAY.
AFTER 04Z...SCATTERED SNOW SHOWERS AND AREAS OF FOG AT RAWLINS
PRODUCING IFR AND MVFR AND MOUNTAIN OBSCUREMENT. VFR ELSEWHERE.
AFTER 15Z...WINDS BECOMING NORTH AND NORTHWEST AFTER COLD FRONTAL
PASSAGE AND INCREASING WITH WINDS GUSTING TO 30 KNOTS. SCATTERED
SHOW SHOWERS PRODUCING MVFR AT RAWLINS TAF WITH VFR AT OTHER
SITES. RUBIN
&&
.PREV DISCUSSION... /ISSUED 509 AM MST FRI NOV 9 2012/
SHORT TERM...TODAY THROUGH SUNDAY NIGHT...
MAIN FORECAST FOCUS WAS GIVEN TO THE HIGH WIND POTENTIAL ACROSS
PORTIONS OF CARBON COUNTY TODAY AND THE RETURN TO WINTRY WEATHER ON
SATURDAY.
BEFORE THEN...EARLY MORNING 11-3.9 FOG PRODUCT SHOWS THE EDGE OF
FOG/LOW STRATUS SLOWLY PROGRESSING WEST ALONG A LUSK TO BRIDGEPORT
LINE. MODELS DO NOT SUGGEST MUCH FURTHER MOVEMENT WEST OF THIS
FOG...SO FOR NOW HAVE KEPT IT EAST OF LUSK/SCOTTSBLUFF/SIDNEY.
ALTHOUGH...WILL NEED TO WATCH THIS CLOSELY THROUGH SUNRISE.
ATTENTION THEN TURNS TO THE UPSTREAM HIGH AMPLITUDE TROUGH THAT WILL
MOVE FROM THE WEST COAST TODAY INTO THE INTERMOUNTAIN WEST TONIGHT
AND SATURDAY. STRONG SOUTHWEST FLOW OUT AHEAD OF THIS TROUGH WILL
BECOME COUPLED TODAY AS THE MIXED LAYER DEEPENS. MEANWHILE...SFC
PRESSURE FALLS ACROSS CENTRAL WYOMING SHOULD FURTHER STRENGTHEN THE
LLVL GRADIENT LATER TODAY. ALTHOUGH AN ATYPICAL HIGH WIND
PATTERN...EXPECT TO SEE THE 50 TO 55 KNOTS OF WINDS AT THE TOP OF
THE MIXED LAYER BE REALIZED LATER THIS MORNING AND DURING THE
AFTERNOON HOURS. SO...HAVE WENT AHEAD AND UPGRADED TO A HIGH WIND
WARNING ACROSS MOST LOWER ELEVATIONS OF CARBON COUNTY TODAY. WINDS
WILL DECOUPLE THROUGH THE EVENING...SO EXPECT THE STRONGEST WINDS TO
SUBSIDE THEN. OTHERWISE EXPECT CLOUDS TO BE ON THE INCREASE FOR MOST
LOCATIONS THROUGH THE DAY AS PACIFIC MOISTURE STREAMS AHEAD OF THE
TROUGH. ONE MORE MILD DAY IN STORE TODAY...THE LIKES OF WHICH WE
WONT SEE AGAIN AT LEAST FOR THE NEXT 7 DAYS. UPSTREAM 00Z SOUNDINGS
HAVE A BROAD AREA OF 5C AT H7...SO EXPECT 50S AND LOW 60S FOR HIGHS
TODAY.
BY TONIGHT...SFC LOW WILL DEEPEN AS IT SLIDES SOUTHEAST ACROSS THE
CWFA. THIS WILL PULL THE COLD FRONT SOUTH INTO NRN ZONES BY AROUND
MIDNIGHT AND THROUGH THE REST OF THE CWFA SATURDAY MORNING.
INITIALLY..SNOW WILL DEVELOP AS A RESULT OF AROUND 40 KNOTS OF
MOIST H7 SOUTHWESTERLY FLOW INTO THE SNOWY/SIERRA MADRES LATE
THIS EVENING. AS THE SFC FRONT DEEPENS AND THE FAVORABLE LFQ OF H3
ARRIVES ON SATURDAY...WILL BEGIN TO SEE PRECIPITATION SPILL OUT
INTO LOWER ELEVATIONS. TEMPERATURES MAY BE WARM ENOUGH TO SEE A
PERIOD OF LIGHT RAIN INITIALLY...ESPECIALLY OVER THE SRN NE
PANHANDLE. HOWEVER CHANGE-OVER WILL OCCUR QUICKLY AS COLD AIR
FILTERS IN BEHIND THE COLD FROPA. WILL NEED TO WATCH THIS CLOSELY
AS ANY RAIN OUT AHEAD OF THE COLD FRONT MAY CREATE SLIPPERY
DRIVING CONDITIONS. THE BEST H7-H5 FRONTOGENESIS WILL BECOME
JUXTAPOSED WITH BEST JET SUPPORT ON SATURDAY AFTERNOON/EVENING
SUGGESTING THAT THE BEST SNOW POTENTIAL WILL OCCUR THEN. 00Z MODEL
OUTPUT CONTINUES TO TREND TOWARDS A SPLIT TROUGH SOLUTION WHICH
WILL LIMIT SNOWFALL POTENTIAL. ONLY TRENDED TOWARDS THIS DRIER
SOLUTION AND WILL AWAIT FURTHER CONFIRMATION FROM SUBSEQUENT RUNS.
STILL THINK THAT AN INCH OR TWO WILL CATCH MOST OF THE LOWER
ELEVATIONS...WITH PERHAPS UP TO 3 IN AREAS CLOSEST TO THE
MOUNTAINS. THE SNOWIES/SIERRA MADRES WILL FARE THE BEST WITH 6 TO
10 INCHES EXPECTED WITH HIGHER AMOUNTS POSSIBLE ALONG WEST FACING
SLOPES. SO...DID ISSUE A WINTER WEATHER ADVISORY FOR THAT AREA
BEGINNING AT 9 PM TONIGHT AND CONTINUING THROUGH MIDNIGHT SATURDAY
NIGHT. THE UPPER TROUGH WILL REMAIN OVER THE AREA ON
SUNDAY...WHICH SHOULD RESULT IN SOME RESIDUAL SNOW SHOWERS
ESPECIALLY OVER THE MOUNTAINS. OTHERWISE...EXPECT A GENERALLY DRY
DAY FOR SUNDAY.
THE OTHER MAJOR IMPACT FROM THIS SYSTEM WILL BE THE FRIGID AIR MASS
THAT WILL USHER IN THE COLDEST AIR THUS FAR THIS SEASON. H7
TEMPERATURES OF -14C TO -16C WILL PREVENT HIGH TEMPERATURES FROM
CLIMBING OUT OF THE 20S AT MOST LOCATIONS ON SUNDAY.
LIKEWISE...OVERNIGHT LOW TEMPERATURES WILL DIP INTO THE SINGLE
DIGITS AND TEENS FOR BOTH SATURDAY AND SUNDAY NIGHTS. WOULD NOT BE
AT ALL SURPRISED FOR SHELTERS VALLEYS WEST OF THE LARAMIE RANGE TO
FALL BELOW ZERO...ESPECIALLY ON SUNDAY NIGHT.
LONG TERM...MONDAY THROUGH FRIDAY...UPPER LEVEL WINDS WILL BACK TO
THE WEST ON MONDAY AS A BROAD RIDGE BUILDS OVER THE WESTERN CONUS
FOR MONDAY THROUGH WEDNESDAY. EXPECTING DRY CONDITIONS UNDER
PARTLY TO MOSTLY CLOUDY SKIES AS A MID/HIGH LEVEL CLOUD DECK
STREAMS OVERHEAD IN THIS ZONAL PATTERN. WINDS WILL REMAIN BREEZY
ALONG AND WEST OF THE LARAMIE RANGE THROUGH THIS TIME AS WELL WITH
THE RIDGE BUILDING IN FROM THE WEST. 700MB TEMPERATURES WILL
STEADILY CLIMB THROUGH THE WEEK BACK TO NEAR 0C BY WEDNESDAY...SO
EXPECTING HIGH TEMPS TO BECOME MORE NORMAL FOR THIS TIME OF YEAR
THROUGH THE WEEKEND. THE NEXT SYSTEM WILL MOVE ACROSS THE ROCKIES
THURSDAY NIGHT AND FRIDAY...DRAGGING A COLD FRONT THROUGH THE
FORECAST AREA EARLY FRIDAY MORNING. 00Z ECMWF IS QUITE A BIT
SLOWER THAN THE 00Z GFS...PREVIOUS RUNS...AND THE GFS ENSEMBLE
MEAN...SO WILL DISCOUNT THE 00Z ECMWF FOR THIS FORECAST. THE MAIN
UPPER TROUGH AXIS MOVES OVERHEAD 06Z FRIDAY WITH FLOW ALOFT
BECOMING SOUTHWEST AHEAD OF THE TROUGH. THE LEESIDE SFC TROUGH
WILL DEEPEN AHEAD OF THE UPPER TROUGH AS WELL WITH SOUTHEAST SFC
FLOW STRENGTHENING ACROSS THE EASTERN PLAINS ON THURSDAY. THE COLD
FRONT WILL MOVE EAST EARLY FRIDAY MORNING WITH SLIGHTLY COOLER
TEMPS EXPECTED FOR FRIDAY. MOIST SOUTHWEST FLOW AHEAD OF THE
TROUGH WILL BRING A SLIGHT CHANCE FOR RAIN/SNOW SHOWERS ALONG THE
WESTERN SLOPES OF THE MOUNTAINS BEGINNING THURSDAY AND CONTINUING
THE WEEKEND.
AVIATION...12Z TAF ISSUANCE...STRONG WEST TO SOUTHWEST WINDS ARE
EXPECTED TODAY ALONG AND WEST OF THE LARAMIE RANGE...WITH GUSTS
IN EXCESS OF 45 KTS EXPECTED FROM RAWLINS TO ARLINGTON. THESE WINDS
WILL EASE OVERNIGHT. ACROSS THE EAST...WIND WILL BE OUT OF THE
SOUTHEAST AT 10 TO 15 KTS...WITH IFR CIGS AND VSBYS ACROSS THE
NORTHERN PANHANDLE SITES THROUGH MIDMORNING. EXPECTING VFR THEN TO
RETURN FOR THE REMAINDER OF THE PERIOD IN THE EAST. A LOW PRESSURE
SYSTEM MOVING ACROSS THE REGION TONIGHT AND SATURDAY WILL BRING
SNOW TO THE MOUNTAINS LATE TONIGHT THROUGH TOMORROW...WITH SNOW
SPREADING INTO THE EASTERN PLAINS ON SATURDAY MORNING. LIKELY
TO SEE MVFR TO IFR DEVELOPING SATURDAY WITH OBSCURED MOUNTAINS.
FIRE WEATHER...ONE MORE MILD DAY IN STORE ACROSS THE DISTRICT
TODAY AS THE NEXT STORM SYSTEM BEARS DOWN ON THE REGION LATER
TONIGHT AND CONTINUING INTO THE WEEKEND. WINDY CONDITIONS WILL
DEVELOP TODAY ACROSS LOWER ELEVATIONS OF CARBON COUNTY WITH GUSTS
APPROACHING 60 MPH. THESE WILL SUBSIDE THIS EVENING AS A COLD
FRONT BEGINS TO WORK THROUGH. THIS FRONTAL SYSTEM WILL BRING SNOW
TO THE SNOWIES/SIERRA MADRES TONIGHT...SPILLING OUT ONTO THE
PLAINS ON SATURDAY. SNOWFALL AMOUNTS OF GENERALLY 1 TO 3 INCHES
WILL BE POSSIBLE ACROSS LOWER ELEVATIONS...WITH 6 TO 10 INCHES
ACROSS IN THE SNOWIES/SIERRA MADRES. SNOW WILL BEGIN TO WIND DOWN
LATE SATURDAY NIGHT...GIVING WAY TO MOSTLY DRY CONDITIONS ON
SUNDAY. TEMPERATURES WILL BECOME MUCH COLDER BEHIND THE COLD FRONT
HIGH TEMPERATURES ONLY CLIMBING INTO THE 30S ON SATURDAY...AND 20S
FOR SUNDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...HIGH WIND WARNING UNTIL 6 PM FRIDAY FOR WYZ104-WYZ109-WYZ110.
WINTER WEATHER ADVISORY FROM 9 PM FRIDAY TO MIDNIGHT SUNDAY FOR
WYZ112-WYZ114.
NE...NONE.
&&
$$
UPDATE...WEILAND
SHORT TERM/FIRE WEATHER...HAHN
LONG TERM/AVIATION...RJM
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
405 AM EST SUN NOV 11 2012
.SYNOPSIS...
08Z WATER VAPOR AND H4 RAP ANALYSIS SHOW A HIGHLY AMPLIFIED UPPER
LEVEL PATTERN IN PLACE OVER THE CONUS EARLY THIS MORNING. PATTERN IS
DOMINATED BY AN IMPRESSIVE TROUGH OVER THE INTER-MOUNTAIN
WEST/PLAINS/UPPER MIDWEST. AS A RESULT OF THE IMPRESSIVE HEIGHT
FALLS TO OUR WEST...WE ARE SEEING AN OVERALL AMPLIFICATION TO THE
UPPER RIDGE WHICH NOW COVERS THE GULF OF MEXICO AND SOUTHEAST
PORTION OF THE CONUS. THIS RIDGE WILL HELP KEEP OUR LOCAL WEATHER
GENERALLY DRY AND WARM THE NEXT COUPLE OF DAYS.
AT THE SURFACE...1030+MB HIGH OFF THE MID-ATLANTIC COAST RIDGES ALL
THE WAY DOWN THE EASTERN SEABOARD TO THE GULF OF MEXICO. THIS
POSITIONS IS SUPPLYING OUR REGION WITH A FAIRLY TIGHT PRESSURE
GRADIENT AND RESULTING EASTERLY FLOW. A FEW LOW LEVEL CLOUDS
ASSOCIATED WITH ATLANTIC MOISTURE HAVE BEEN TRAVERSING THE PENINSULA
THIS MORNING WITHIN THE LOW LEVEL FLOW...AND THIS PATTERN WILL
PROVIDE A MIX OF SUN AND CLOUDS FOR TODAYS FORECAST. EARLY MORNING
TEMPERATURES ARE SEASONABLE WITH MANY LOCATIONS DOWN INTO THE
50S...AND EVEN A FEW UPPER 40S OVER THE NORTHERN NATURE COAST ZONES.
&&
.SHORT TERM (TODAY THROUGH TUESDAY)...
TODAY/TONIGHT...PATTERN WILL BE DOMINATED BY STACKED RIDGING. THE
INFLUENCE/LARGE SCALE SUBSIDENCE ASSOCIATED WITH THE UPPER RIDGE CAN
BE SEEN CLEARLY ON THE 00Z KTBW SOUNDING PROFILE WITH A WELL DEFINED
SUBSIDENCE INVERSION AROUND 800MB. THE FORECAST UNDER THIS
SUPPRESSION WILL BE FAIR AND DRY TODAY. THE TIGHT GRADIENT AND AMPLE
SUNSHINE WILL PROMOTE GOOD DIURNAL MIXING. 850MB TEMPS AROUND 11C
AND MIXING SIMILAR TO WHAT WAS SEEN SATURDAY SHOULD ALLOW MANY
LOCATIONS TO TOP OUT WITHIN A DEGREE OR 2 OF 80 THIS AFTERNOON.
THE SLOW MODERATION TO OVERNIGHT LOWS WILL CONTINUE TONIGHT WITH
TEMPS UP A FEW DEGREES FROM THIS MORNING. LOOKING FOR LOW TEMPS
TO GENERALLY BE IN THE UPPER 50S TO AROUND 60.
MONDAY...UPPER RIDGE WILL STILL BE IN CONTROL THROUGH MUCH OF THE
DAY BUT WILL BEGIN TO DE-AMPLIFY IN RESPONSE TO THE EASTWARD
PROPAGATION OF THE CENTRAL U.S. TROUGH. NWP GUIDANCE IS IN GOOD
AGREEMENT THAT THE MAJORITY OF THE ENERGY ASSOCIATED WITH THIS
TROUGH WILL PASS TO OUR NORTH. SURFACE COLD FRONT WILL BE MOVING
ALONG THE NORTHERN GULF COAST DURING MONDAY...AND ANY ASSOCIATED
SHOWER ACTIVITY WILL REMAIN TO THE NW/W OF OUR FORECAST AREA. LOW
LEVEL MOISTURE RECOVERY MAY BE ENOUGH TO ALLOW A FEW LOW-TOPPED
SPEED CONVERGENCE SHOWERS FROM THE EAST COAST TO BEGIN SURVIVING THE
TREK ACROSS THE STATE. CAN NOT RULE OUT A BRIEF SPRINKLE FOR A FEW
SPOTS ON MONDAY...BUT COVERAGE AND IMPACT WOULD BE VERY LOW. FOR NOW
WILL LEAVE RAIN CHANCES AT A SILENT 10%. TEMPERATURES UNDER THE
UPPER RIDGE WILL AGAIN BE ABOVE NORMAL WITH MANY SPOTS REACHING THE
LOWER 80S.
MONDAY NIGHT/TUESDAY...UPPER TROUGH QUICKLY PIVOTS AWAY FROM THE
REGION WITH LEFTOVER MASS FIELDS NOT PROVIDING MUCH OF A PUSH
SOUTHWARD TO THE COLD FRONT. LOOKS LIKE AN ILL-DEFINED BOUNDARY WILL
PUSH INTO THE REGION EARLY TUESDAY AND THEN WASH-OUT. WILL NOT SEE
MUCH IN THE WAY OF CAA WITH THIS FRONT AND TEMPERATURES WILL STAY AT
OR SLIGHTLY ABOVE NORMAL INTO THE MIDDLE OF THE WEEK. ALSO...NOT
ANTICIPATING MUCH IN THE WAY OF DEEP LAYER SYNOPTIC SUPPORT FROM
THIS TROUGH AND LOW LEVEL FOCUS ASSOCIATED WITH THE FRONT WILL NOT
BE IMPRESSIVE EITHER. WILL GO WITH A SLIGHT CHANCE 20% POP FOR A FEW
ISOLATED SHOWERS...GENERALLY NORTH OF THE I-4 CORRIDOR. AT THIS
TIME...THIS FRONT LOOKS TO BE A RATHER UNEVENTFUL PASSAGE IN TERMS
OF SENSIBLE WEATHER.
&&
.LONG TERM (WEDNESDAY THROUGH NEXT SUNDAY)...
WEAK FRONTAL BOUNDARY WILL HAVE STALLED AND BASICALLY DISSIPATED BY
WEDNESDAY SOMEWHERE IN THE VICINITY OF CENTRAL FLORIDA. THE FRONT
ITSELF WILL HAVE VERY LITTLE IMPACT ON THE REGION...BUT SOME
SLIGHTLY DRIER AIR WILL MOVE IN ALONG WITH A RETURN TO TEMPERATURES
CLOSER TO NORMAL FOR THIS TIME OF YEAR.
MODEL DIFFERENCES LEAD TO SOME UNCERTAINTY IN THE FORECAST FOR THE
END OF THE WEEK. A SHORT-WAVE TROUGH WILL BE MOVING EASTWARD ACROSS
THE SOUTHERN STATES...POSSIBLY AS FAR SOUTH AS THE GULF COAST. THE
GFS...CANADIAN...AND ECMWF ALL SHOW THIS FEATURE...BUT NONE OF THEM
AGREE ON TIMING OR AMPLITUDE. THE 12Z ECMWF HAS A SLOW MOVING CLOSED
MID-LEVEL LOW MOVING ACROSS NORTH FLORIDA. THIS RESULTS IN A CHANCE
FOR SHOWERS ACROSS MUCH OF OUR REGION ON THURSDAY...ESPECIALLY NORTH
OF TAMPA BAY. THE GFS SHOWS A WEAKER TROUGH OVER FLORIDA WITH THE
MAIN ENERGY CONTINUING EASTWARD WELL NORTH OF THE STATE. THE
CANADIAN MODEL HAS A VERY SHARP TROUGH AXIS MOVING ACROSS NORTHERN
ALABAMA AND GEORGIA WEDNESDAY NIGHT...THEN SWINGING RAPIDLY OFF THE
EASTERN SEABOARD BY MID DAY THURSDAY. THE SPEED AND AMPLITUDE OF
THIS FEATURE WILL HAVE AN IMPACT ON THE NEXT UPSTREAM SYSTEM AS
WELL...WHICH POTENTIALLY CROSSES FLORIDA ON SATURDAY AND MAY BE A
CATALYST FOR DEVELOPING LOW PRESSURE IN THE ATLANTIC BEYOND THIS
FORECAST PERIOD. THE BEST COURSE OF ACTION AT THIS TIME WOULD BE TO
USE A BLEND OF GUIDANCE...IN THIS CASE THE GFS AND ECMWF TO
INTRODUCE A SLIGHT CHANCE OF SHOWERS EACH DAY MAINLY NORTH OF TAMPA
BAY AND OVER THE INTERIOR.
&&
.AVIATION...
VFR NEXT 24 HOURS. MAY SEE OCCASIONAL CEILINGS BETWEEN 4000 AND 6000
FEET TODAY. WINDS WILL BECOME GUSTY FROM THE EAST DURING THE
AFTERNOON HOURS.
&&
.MARINE...
A STRONG AREA OF HIGH PRESSURE WILL CONTINUE TO RIDGE DOWN THE
EASTERN SEABOARD TO THE GULF OF MEXICO KEEPING THE LOCAL GRADIENT
TIGHT THROUGH THE DAY. THE INFLUENCE OF THIS RIDGE OF HIGH PRESSURE
WILL WEAKEN BY MONDAY NIGHT AND TUESDAY AS A WEAK COLD FRONT
APPROACHES FROM THE WEST. THIS COLD FRONT WILL DISSIPATE OVER THE
REGION TUESDAY NIGHT AND WEDNESDAY AS HIGH PRESSURE ONCE AGAIN BUILD
TO OUR NORTH.
&&
.FIRE WEATHER...
NO SIGNIFICANT FIRE WEATHER CONCERNS ARE ANTICIPATED THROUGH THE
EARLY PORTION OF THE WEEK. A FEW LOCATIONS WILL SEE RELATIVE
HUMIDITY VALUES DROP INTO THE UPPER 30S THIS AFTERNOON ALONG WITH
BREEZY EASTERLY WINDS. THESE CONDITIONS WILL AID THE SPREAD OF
WILDFIRES...HOWEVER RED FLAG CRITERIA ARE NOT EXPECTED TO BE MET.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 82 64 81 64 / 0 0 10 10
FMY 82 63 83 62 / 0 0 10 10
GIF 80 60 82 61 / 10 10 10 10
SRQ 82 62 81 63 / 0 0 10 10
BKV 81 57 82 58 / 0 0 10 10
SPG 79 66 80 67 / 0 0 10 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/MARINE/FIRE WX...MROCZKA
LONG TERM/AVIATION...JILLSON
AREA FORECAST DISCUSSION
NWS LINCOLN IL
246 AM CST SUN NOV 11 2012
.DISCUSSION...
ISSUED 246 AM CST SUN NOV 11 2012
BIGGEST CHALLENGES THIS PACKAGE ARE WINDS TODAY/THIS EVENING AND
MODEL SPREAD TOWARD THE END OF THE WEEK.
SHORT TERM...TODAY AND TONIGHT
LOOKS LIKE A WINDY DAY ACROSS CENTRAL AND SOUTHEAST ILLINOIS.
THERE IS SOME SPREAD IN FORECAST WIND SPEEDS. STRONGER NAM SEEMS
MORE REASONABLE GIVEN MATCHING UP CURRENT WINDS AND THE HIGHER
RESOLUTION IN THE BOUNDARY LAYER COMPARED TO THE GLOBAL MODELS.
FORECAST GRADIENT WINDS SUGGEST SUSTAINED SPEEDS SHOULD SURPASS
ADVISORY LEVELS. EVEN THOUGH THE GFS GRIDS DO NOT INDICATED AS
HIGH OF SPEEDS AS THE NAM AND HIGH RES MODELS...MAV GUIDANCE IS
INDICATING ADVISORY CRITERIA. NAM MODEL SOUNDINGS SHOW 40+ KTS
SEVERAL HUNDRED FEET OFF THE SURFACE AND SUFFICIENT MIXING OCCURS...THE
GUST CRITERIA OF 45 KTS MAY ALSO BE SURPASSED. CLOUDS MAY LIMIT
MIXING SOME...BUT IT WONT TAKE MUCH TO TAP INTO THE HIGHER
MOMENTUM OFF THE SURFACE. 04Z HRRR SHOWS 40-50 KT GUSTS ACROSS
MOST OF THE AREA BY 19Z. LOOKS LIKE HIGHEST SPEEDS SHOULD DEVELOP
BY LATE MORNING OVER WEST CENTRAL IL AND THEN SPREAD QUICKLY
SOUTHEAST THROUGH MIDDAY AND EARLY AFTERNOON. WILL BE ISSUING WIND
ADVISORY FOR ENTIRE FORECAST AREA.
WINDS SHOULD DECREASE FROM NORTHWEST TO SOUTHEAST DURING THE
EVENING SHORTLY AFTER COLD FRONTAL PASSAGE. SPEAKING OF THE FRONT...
00Z MODEL SUITE IN GOOD AGREEMENT ON TIMING OF INCOMING COLD
FRONT AND POST-FRONTAL PRECIP. HOWEVER...MOST OF THE MODELS ARE
NOT HANDLING THE PRE-FRONTAL PRECIP CURRENTLY ALONG AND WEST OF
THE MISSISSIPPI IN THE WARM SECTOR. LATEST ECMWF(00Z) DOES HINT AT
AN AREA OF PRECIP OVER WEST CENTRAL IL AT 12Z. ORIGINALLY WAS
THINKING THAT ANY PRECIP CHANCE WOULD WAIT FOR THE FRONT...NOT
REACHING WESTERN FORECAST AREA UNTIL LATE MORNING...BUT WITH ONGOING
SHOWERS WILL INCLUDE A CHANCE OF RAIN FOR THE ENTIRE MORNING OVER
THE WEST.
LOOKS LIKE A ANAFRONT STRUCTURED FRONT AND THE BULK OF PRECIP SHOULD BE
MOSTLY ALONG AND BEHIND THE BOUNDARY. PRECIP WATER REMAINS WELL
ABOVE CLIMATOLOGY...99 PERCENTILE FOR NOVEMBER...AND ALTHOUGH THE
PERIOD OF RAIN AT ANY ONE SPOT SHOULDNT BE MORE THAN 12
HOURS...QPF SHOULD APPROACH AN INCH IN MOST AREAS WITH LOCALLY
HIGHER AMOUNTS. DESPITE MEAGER INSTABILITY...SHEAR IS IMPRESSIVE
AND MAY BE SUFFICIENT FOR ISOLATED EMBEDDED THUNDER BEHIND THE
FRONT WHICH COULD LOCALLY ENHANCE THE RAINFALL RATES.
STRONG COLD ADVECTION SURGES INTO THE AREA BEHIND THE FRONT AND
THERE MAY BE A BRIEF PERIOD OF A MIX OR A CHANGE TO SNOW BEFORE
THE PRECIP ENDS EARLY MONDAY. GROUND TEMPS SHOULD BE WARM ENOUGH
TO LIMIT ANY ACCUMULATION.
LONG TERM...MONDAY THROUGH SATURDAY
AFTER PRECIP MOVES OUT MONDAY MORNING...BIG STORY WILL BE THE
COLD ADVECTION. TEMPS WILL BE SUPPRESSED WITH HIGHS ON MONDAY
BEING SOME 20-25 DEGREES COOLER THAN SUNDAY IN MOST LOCATIONS AND
WITH BRISK WEST WINDS...WIND CHILLS WILL STAY OR FALL INTO THE 20S
AND 30S. CLEARING SHOULD SPREAD ACROSS THE AREA EARLY MONDAY. HIGH
PRESSURE CENTERS OVER ILLINOIS ON TUESDAY AND TUESDAY MORNING
SHOULD HAVE GOOD RADIATION AL COOLING CONDITIONS WITH A HARD FREEZE
LIKELY FOR MOST OF CENTRAL AND SOUTHEAST ILLINOIS.
850 MB TEMPS SLOWLY REBOUND AS THE AIR MASS MODERATES AFTER
TUESDAY AND TEMPS SHOULD REACH CLOSE TO NORMAL FOR THE LATER PART
OF THE WEEK.
MODEL SPREAD INCREASES SIGNIFICANTLY IN THE NAEFS AND OPERATIONAL
MODELS FOR THE LATER HALF OF THE WEEK WITH GENERALLY WEAK FLOW AND
ABOVE NORMAL HEIGHTS. MOST LIKELY SCENARIO SUGGESTS HIGH PRESSURE
RIDGING INTO IL FROM THE NORTHEAST KEEPING DRY WEATHER IN PLACE
INTO THE WEEKEND.
BARKER
&&
.AVIATION...
ISSUED 1139 PM CST SAT NOV 10 2012
VFR CONDITIONS WILL PREVAIL OVERNIGHT AT ALL TAF SITES. CLOUDS
WILL START HAS HIGH CIRRUS AND THEN LOWER CLOUDS AROUND AROUND
4KFT WILL ADVECT INTO THE REGION. CLOUD COVER WILL BEGIN AS BROKEN
IN THE WEST AT SPI AND PIA...AND SLOWLY MOVE EAST AFFECTING
DEC/BMI AND CMI. THIS WILL ALL BE AHEAD OF THE FRONT. THEN WHEN
THE FRONT AND PCPN ARRIVES...CIGS WILL DROP TO LOWER MVFR VERY
QUICKLY...AROUND 1.2-1.5KFT. VIS WILL ALSO DECREASE RAPIDLY WITH
THE PCPN. WILL START WITH VCSH THREE HOURS BEFORE THE FRONT AS
THERE COULD BE SOME ISOLATED TO SCATTERED SHOWERS IN THE WARM
SECTOR JUST AHEAD OF THE FRONT. HOWEVER...WARM AIR MASS SHOULD BE
WELL CAPPED HOLDING MOST PCPN BACK TO BE ALONG AND BEHIND THE
FRONT. WILL HAVE SHOWERS WITH VCTS ALONG AND BEHIND THE FRONT
STARTING IN THE EVENING HOURS...00Z-03Z. WINDS WILL REMAIN GUSTY
OVERNIGHT AND THEN INCREASE IN SPEED TOMORROW. LOWE LEVEL JET OF
40-45KTS NOW WILL INCREASE AS WELL TO AROUND 50+KTS...SO EVENING
WITH SLIGHTLY GUSTY WINDS ON THE SFC NOW...WILL KEEP WS OF 50KTS
GOING FOR OVERNIGHT. GUSTY WINDS WILL DECREASE JUST AHEAD OF THE
FRONT BUT THEN DECREASE MORE AS THEY SHIFT TO WEST-NORTHWESTERLY
BEHIND THE FRONT.
AUTEN
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 10 AM THIS MORNING TO 8 PM CST THIS EVENING
FOR ILZ027>031-036>038-040>057-061>063-066>068-071>073.
&&
$$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1022 PM CST SAT NOV 10 2012
.UPDATE 11/06Z AVIATION DISCUSSION...
.SHORT TERM /TONIGHT/...
HAVE UPDATED WINDS OVER WESTERN IOWA FOR STRONGER SFC GRADIENT AHEAD
OF FRONT. OTHERWISE...FORECAST LOOKS TO BE ON TARGET WITH THUNDER
TIMING AND COLDER TEMPERATURES BY MORNING.
.PREVIOUS SHORT TERM /TONIGHT/...
ALL ELEMENTS ARE CONCERNS THIS EVENING WITH TREMENDOUS CHANGE IN THE
WEATHER. PARENT LONG WAVE TROUGH OF UPSTREAM SYSTEM IS STILL WEST
OF ROCKIES BUT LEAD CO AND NE SHORT WAVES CONTINUE TO PRODUCE
WIDESPREAD SURFACE PRESSURE FALLS ALONG AND AHEAD OF FRONTAL
BOUNDARY WHICH EXTENDS ACROSS NE INTO SIOUXLAND AREA AT 20Z. NO
ISALLOBARIC MAX OR PUSH EVIDENT AS OF YET SO DO NOT EXPECT MUCH
MOVEMENT FOR AWHILE. WARM SECTOR AIRMASS STILL HAS A WAYS TO GO
BEFORE BECOMING SURFACE BASED WITH 20Z SUBJECTIVE ANALYSIS SHOWING
ONLY 100 J/KG MLCAPES AND CINH ONLY DOWN TO 50 J/KG IN SMALL AREA
ACROSS KS/NE BORDER. LATEST RAP AND NAM SUGGEST ONLY A SMALL WINDOW
FOR THERMODYNAMICS FAVORABLE FOR SURFACE CONVECTION UPSTREAM THROUGH
EARLY EVENING...AND WHAT THERE IS FADES INTO THE NIGHT FARTHER
EAST SO DO NOT REALLY FEEL TORNADOES OR SURFACE BASED STORMS A
THREAT.
HOWEVER LATEST NAM/HRRR AND WRF RUNS ALL SUGGEST SIMILAR
PROGRESSIONS WITH CONVECTION DEVELOPING ACROSS ERN NE ASSOCIATED
WITH FORCING THAT IS CURRENTLY PRODUCING NE/SD SNOW. THIS MOVES
INTO WRN FORECAST AREA AFTER 03Z AND THEN ACROSS REMAINDER OF THE
AREA OVERNIGHT. MODELS ACTUALLY DEPICT FORCING MAX 06-12Z SO PRECIP
MAY ACTUALLY EXPAND EARLY SUN MORNING. WIND WOULD SEEM TO BE OUR
GREATEST SEVERE THREAT WITH STORM MOTION SW-NE 50-60KTS...BUT WITH
WANING INSTABILITY AND SOUNDINGS MOISTENING DO NOT THINK THIS IS A
BIG THREAT OVERALL. TEMPERATURES WILL BE PROBLEMATIC WITH SHARP
GRADIENT ACROSS FRONTAL BOUNDARY. TEMPS SHOULD FALL SHARPLY WITH
FRONT NW...BUT WILL LIKELY NOT REACH FAR SERN SECTIONS UNTIL BEYOND
THIS PERIOD.
.LONG TERM /SUNDAY THROUGH SATURDAY/...
MAIN FORECAST CONCERNS FOR LONG TERM FOCUS AROUND BEGINNING OF
LONG TERM AND PRECIPITATION AND TEMPERATURES FOR SUNDAY AND INTO
SUNDAY NIGHT. STRONG COLD FRONT WILL PUSH ACROSS THE CWA
THROUGHOUT THE DAY SUNDAY...AND ANTICIPATE FROPA NEAR 12Z ACROSS
THE WEST...AND AROUND 15Z FOR CENTRAL LOCATIONS. THIS WILL ALLOW
TEMPERATURES TO DROP THROUGHOUT THE DAY...WITH HIGH TEMPERATURES
OCCURRING BETWEEN VERY NEAR 12Z-15Z OR A LITTLE LATER FURTHER SE.
GOOD MOISTURE ASSOCIATED WITH FRONT AND STRONG FRONTOGENESIS AND
LIFT WILL ALLOW FOR PRECIPITATION WITH FRONT. MOST OF THIS
PRECIPITATION WILL COME AS RAIN WITH WARMER TEMPERATURES AHEAD OF
FRONT. HOWEVER...CLOSER TO THE FRONT AND LINGERING POST-FRONTAL
PRECIPITATION WILL LIKELY BE MIXED.
MIXED PRECIPITATION WILL BE MOST LIKELY ACROSS THE WEST SUNDAY
MORNING BEFORE SWITCHING OVER TO RAIN/SNOW IN THE AFTERNOON. GFS
AND NAM SOUNDINGS DIFFER SLIGHTLY WITH PRECIP TYPE AT
SURFACE...MAINLY DUE TO TIMING DIFFERENCES WITH FROPA.
HOWEVER...FEEL THERE IS A GOOD CHANCE FOR RN/IP NEAR FRONT. WITH
ICE INTRODUCTION ALOFT...FALLING THROUGH STRONG WARM LAYER...NEAR
OR ABOVE 6C...BEFORE STRONG COLD LAYER CLOSER TO SURFACE WITH
FRONT. DEPTH OF NEAR SURFACE COLD LAYER VARIES BY MODEL...BUT MOST
INDICATE A GOOD CHANCE FOR REFREEZING AND COULD SEE SLEET. SURFACE
TEMPERATURES WILL BE SLIGHTLY ABOVE FREEZING...FALLING TO NEAR
FREEZING WITH APPROACHING COLD FRONT. THEREFORE CANNOT RULE OUT
CHANCE FOR LOCALIZED FZRN. HOWEVER...FEEL THIS THREAT IS VERY
MINIMAL WITH WARM SURFACE TEMPERATURES AND SMALL TIMING WINDOW.
HOWEVER...LOCALIZED ICING ON ELEVATED SURFACES IS POSSIBLE EARLY
SUNDAY MORNING ACROSS THE NORTHWEST AND WEST. STRONG FRONT PUSHES
THROUGH QUICKLY PUSHING SOUNDING TEMPS BELOW ZERO THROUGH
COLUMN...ENDING CHANCES FOR MELTING IN WARM LAYER...WITH PRECIP AT
SURFACE CHANGING TO RN/SN MIX. AGAIN...EXPECT LITTLE IN THE WAY OF
ACCUMULATION WITH WARM SURFACE TEMPERATURES AND BULK OF
PRECIPITATION PREFRONTAL AND FALLING AS RAIN.
PRECIPITATION WILL PUSH OUT BY SUNDAY NIGHT...WITH COLD
TEMPERATURES REMAINING. COULD SEE SOME LIGHT FLURRIES ACROSS THE
NORTH MONDAY NIGHT AS LOW TRACKS ACROSS THE NORTH. HOWEVER...NOT A
LOT OF LIFT ASSOCIATED WITH THIS AND HAVE ONLY KEPT FLURRIES
MENTIONED WITH NO ACCUMULATION. FOCUS FOR THE LONG TERM SWITCHES
TO TEMPERATURES THROUGH THE WEEK AS NEARLY ZONAL FLOW SETS UP
ACROSS THE REGION. FEW WAVES WILL PUSH THROUGH THE FLOW...BUT
LITTLE MOISTURE AND HAVE NOT INCLUDED PRECIPITATION CHANCES.
TEMPERATURES WILL STEADILY WARM WITH SOUTHERLY SURFACE FLOW...WITH
HIGHS IN THE 40S AND 50S FOR THE END OF THE WEEK. MODELS CONTINUE
TO DEVELOP ANOTHER AREA OF LOW PRESSURE EAST OF THE ROCKIES FOR
LATE IN THE WEEK. HOWEVER...HAVE SIGNIFICANTLY SLOWED DOWN THIS
DEVELOPMENT AND HAVE THEREFORE CUT BACK ON PRECIPITATION CHANCES
FOR FRIDAY WITH ONLY CHANCES MENTIONED SATURDAY. MAY SEE A
CONTINUED SLOWING TREND WITH THIS SYSTEM AND WILL LIKELY SEE BEST
CHANCES FOR PRECIPITATION RETURNING AGAIN AFTER THE END OF THE
PERIOD.
&&
.AVIATION...11/06Z
AS THE FRONT CROSSES THE STATE FROM 06Z WEST TO 13Z EAST WINDS WILL
SWING AROUND TO NW DIRECTION AND INCREASE DURING THE MORNING HOURS.
SHOWERS AND ISO THUNDER WILL CONTINUE OVERNIGHT AS FRONT MOVES EAST
AND SHORT WAVE IMPULSE RIDES ALONG THE BOUNDARY NORTHEAST THROUGH
IOWA. AS COLD AIR RUSHES INTO THE BACK SIDE OF THE SYSTEM RAIN MIXES
IN WITH SNOW AND THEN CHANGES OVER TO SNOW AS THE SYSTEM DEPARTS.
WINDS WILL GRADUALLY DIMINISH TOWARD 00Z AS SFC GRADIENT WEAKENS.
CIGS WILL REMAIN RATHER LOW FOR MUCH OF THE DAY BUT LIFT TOWARD
20-00Z TIMEFRAME. WITH SYSTEM HEADING EAST WILL SEE WINDS GRADUALLY
DIMINISH THROUGH THE REMAINDER OF THE TAF FCST.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...SMALL/REV
LONG TERM...AWB
AVIATION...REV
AREA FORECAST DISCUSSION...CORRECTED AVIATION SECTION
NWS DODGE CITY KS
1153 PM CST SAT NOV 10 2012
...UPDATED FOR AVIATION...
.SYNOPSIS...
ISSUED AT 336 PM CST SAT NOV 10 2012
AN INTENSE STORM SYSTEM WAS MATURING OVER THE ROCKIES AND ADJACENT
GREAT PLAINS TODAY. AFTERNOON RAP ANALYSIS SHOWED A 400MB JET STREAK
OF 100+ KNOTS EXTENDING CYCLONICALLY FROM NORTHEASTERN NEW MEXICO
THROUGH CENTRAL ARIZONA INTO CENTRAL CALIFORNIA. THIS SIGNIFICANT
CYCLONICALLY CURVED JET HAS HELPED SPAWN A DEEP SURFACE LOW AROUND
993MB OVER EASTERN COLORADO THIS AFTERNOON. LOWER-MID TROPOSPHERIC
WIND SPEEDS FROM THE SOUTHWEST WERE 50 TO 70 KNOTS, WHICH WAS THE
TOP OF THE MIXED LAYER IN MANY PLACES ACROSS THE HIGH PLAINS. THIS
LED TO WIDESPREAD SURFACE HIGH WIND EVENT WITH NUMEROUS OBS GUSTING
50 TO EVEN 60 KNOTS AT TIMES. MOST IMPRESSIVELY WAS A RECENT
OBSERVATION AT TUCUMCARI NEW MEXICO OF A 64 KNOT GUST. WIDESPREAD
BLOWING DUST WAS ALSO OCCURRING WITHIN THE HIGH WIND AREA,
EXACERBATED BY THE LONG TERM DROUGHT CONDITIONS. A SHALLOW, NEARLY
STATIONARY SURFACE FRONT THIS MORNING LIFTED BACK NORTH FROM
NORTHWEST KANSAS INTO CENTRAL NEBRASKA AS A WARM FRONT WITH THE
SURFACE LOW STRENGTHENING. THIS QUASI-STATIONARY FRONT AT 19Z
EXTENDED FROM THE 993MB SURFACE LOW NORTHEAST OF LA JUNTA, COLORADO
TO NEAR GOODLAND, KS TO COLUMBUS, NE. THE SURFACE BAROCLINIC ZONE
WAS VERY IMPRESSIVE WITH A TEMPERATURE OF 17F AT CASPER, WYOMING
NORTH OF THE FRONT IN THE ARCTIC AIRMASS AND 79F AT HAYS, KANSAS.
&&
.SHORT TERM...(THIS EVENING AND OVERNIGHT)
ISSUED AT 336 PM CST SAT NOV 10 2012
THE HIGH WIND EVENT WILL CONTINUE WEST OF THE DRYLINE THROUGH 23Z OR
SO, AT WHICH POINT WINDS WILL SLOWLY SLACKEN OFF WITH DUST SETTLING.
AS FAR AS THE PRECIPITATION CHANCES GO, NO CHANGE IN THE CURRENT
FORECAST IS EXPECTED. DEWPOINT TEMPERATURES HAVE NOT BEEN ANY HIGHER
THAN THE MID 50S, WHICH RESULTED IN CAPE 800-1000 J/KG. DESPITE THE
VERY IMPRESSIVE LOW LEVEL AND DEEP LAYER SHEAR, THE LACK OF
APPRECIABLE INSTABILITY AND LOW LEVEL MOISTURE SHOULD PRECLUDE
WIDESPREAD SEVERE WEATHER. THAT BEING SAID, INTENSE MID LEVEL COLD
ADVECTION WILL BE INCREASING, ALLOWING CAPE PROFILES TO IMPROVE THIS
EVENING. WINDOW FOR SEVERE WEATHER SHOULD BE DURING THE 00-04Z TIME
FRAME, WITH THE LINE OF FORCING AND PACIFIC COLD FRONT MOVING
THROUGH SOUTHWEST KANSAS/WESTERN PORTIONS OF SOUTH CENTRAL KANSAS.
THE CANADIAN COLD FRONT WILL BE MOVING THROUGH DURING THE 09-12Z
TIME FRAME ACROSS SOUTHWEST KANSAS, AT WHICH POINT WE WILL SEE
STRONG COLD AIR ADVECTION WITH -8 TO -11C 850MB TEMPERATURES DRIVING
SOUTH. THERE WILL BE SLIGHT DOWNSLOPE MODIFICATION OF THIS AIRMASS
AS WESTERLY COMPONENT MOMENTUM INCREASES OFF THE ROCKIES OF COLORADO
AND WYOMING. WITH THE ADVECTION OF THE MODIFIED ARCTIC AIRMASS, LOW
STRATUS MAY BE A CONCERN AND WILL BUMP UP THE SKY GRIDS A LITTLE BIT
TO ACCOUNT FOR A LITTLE MORE CLOUD THAN EARLIER THOUGHT WITH THE
INITIAL ONSET OF THE COLD AIR AROUND 09Z OR SO.
.LONG TERM...(SUNDAY THROUGH SATURDAY)
ISSUED AT 336 PM CST SAT NOV 10 2012
COLD AIR WILL INVADE WESTERN KANSAS BEHIND THE FRONT BY EARLY SUNDAY
MORNING. HOWEVER, SOME DOWNSLOPE MODIFICATION ON THE WESTERN EDGE OF
THE COLD AIRMASS WILL ALLOW TEMPERATURES TO RISE INTO THE LOWER TO
MID 40S IN MOST LOCATIONS. THE COLDEST NIGHT SO FAR THIS FALL IS
EXPECTED BY SUNDAY NIGHT AS WINDS DECREASE AND CLOUD COVER THINS.
LOWS SHOULD BE IN THE UPPER TEENS TO LOWER 20S BY MONDAY MORNING.
FAIRLY CHILLY AIR WILL PERSIST ON MONDAY AS THE COLD SURFACE HIGH
PRESSURE WILL STILL BE JUST OFF TO THE SOUTHEAST, WITH SEA LEVEL
PRESSURES STILL AROUND 1030MB OVER WESTERN KANSAS. HIGHS SHOULD
ONLY REACH INTO THE UPPER 40S TO LOWER 50S. ANOTHER COLD NIGHT
CAN BE EXPECTED MONDAY NIGHT AS SURFACE HIGH PRESSURE LINGERS TO OUR
EAST. LOWS OUGHT TO BE IN THE 20S.
MAINLY ZONAL MID TO HIGH LEVEL FLOW CAN BE EXPECTED TUESDAY THROUGH
SATURDAY. WEAK LEE TROUGHING WILL DEVELOP IN RESPONSE TO THE
MID-LEVEL DOWNSLOPE FLOW ON TUESDAY AND PERSIST INTO THURSDAY. THIS
WILL LEAD TO SOUTHERLY LOW LEVEL WINDS AND WARMER HIGHS IN THE UPPER
50S AND LOWER 60S. SOME BOUNDARY LAYER DECOUPLING CAN BE EXPECTED
EACH NIGHT GIVEN THE RATHER WEAK PRESSURE GRADIENT. AND GIVEN THE
RELATIVELY DRY AIR AT LOWER LEVELS, TEMPERATURES SHOULD HAVE NO
PROBLEM FALLING INTO THE 30S EACH NIGHT THROUGH FRIDAY. SOME 20S
CANNOT BE RULED OUT IN LOW-LYING AREAS.
A SHORTWAVE TROUGH IS ADVERTISED BY THE VARIOUS MODELS TO APPROACH
THE PLAINS BY LATE FRIDAY INTO SATURDAY. GIVEN THE PROGRESSIVENESS
OF THIS SYSTEM, PRECIPITATION IS NOT LIKELY AS LOW-LEVEL MOISTURE
WILL NOT MAKE IT THIS FAR WEST. HOWEVER, SINCE THE MODELS DO SHOW
SOME MID-LEVEL MOISTURE, ISENTROPIC LIFT AND SMALL AMOUNTS OF QPF,
VERY SMALL CHANCES FOR RAIN WERE MAINTAINED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1150 PM CST SAT NOV 10 2012
11-3.9 MICRON SATELLITE IMAGERY AND METAR OBSERVATIONS INDICATE
WIDESPREAD MVFR STRATUS IS RAPIDLY SPREADING SOUTHWARD ACROSS WEST
CENTRAL KANSAS. THE SOUTHWARD SPEED OF THE LEADIND EDGE INDICATES
THE STRATUS IS LIKELY TO IMPACT THE KGCK AND KDDC TERMINALS BEFORE
08 UTC. THE WIDESPREAD EXTENT OF THE STRATUS SHOULD BE ENOUGH TO
MAINTAIN HIGH CONFIDENCE IN LOW STRATUS THROUGH THE MORNING UNTIL
STRONG INSOLATION BEGINS TO WARM THE LOWER BOUNDARY LAYER.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 31 44 21 52 / 10 0 0 0
GCK 28 43 19 52 / 10 0 0 0
EHA 28 44 21 51 / 10 10 10 0
LBL 30 44 20 52 / 10 10 10 0
HYS 30 42 19 51 / 10 0 0 0
P28 40 46 23 52 / 50 0 10 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...UMSCHEID
SHORT TERM...UMSCHEID
LONG TERM...FINCH
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1151 PM CST SAT NOV 10 2012
...UPDATED FOR AVIATION...
.SYNOPSIS...
ISSUED AT 336 PM CST SAT NOV 10 2012
AN INTENSE STORM SYSTEM WAS MATURING OVER THE ROCKIES AND ADJACENT
GREAT PLAINS TODAY. AFTERNOON RAP ANALYSIS SHOWED A 400MB JET STREAK
OF 100+ KNOTS EXTENDING CYCLONICALLY FROM NORTHEASTERN NEW MEXICO
THROUGH CENTRAL ARIZONA INTO CENTRAL CALIFORNIA. THIS SIGNIFICANT
CYCLONICALLY CURVED JET HAS HELPED SPAWN A DEEP SURFACE LOW AROUND
993MB OVER EASTERN COLORADO THIS AFTERNOON. LOWER-MID TROPOSPHERIC
WIND SPEEDS FROM THE SOUTHWEST WERE 50 TO 70 KNOTS, WHICH WAS THE
TOP OF THE MIXED LAYER IN MANY PLACES ACROSS THE HIGH PLAINS. THIS
LED TO WIDESPREAD SURFACE HIGH WIND EVENT WITH NUMEROUS OBS GUSTING
50 TO EVEN 60 KNOTS AT TIMES. MOST IMPRESSIVELY WAS A RECENT
OBSERVATION AT TUCUMCARI NEW MEXICO OF A 64 KNOT GUST. WIDESPREAD
BLOWING DUST WAS ALSO OCCURRING WITHIN THE HIGH WIND AREA,
EXACERBATED BY THE LONG TERM DROUGHT CONDITIONS. A SHALLOW, NEARLY
STATIONARY SURFACE FRONT THIS MORNING LIFTED BACK NORTH FROM
NORTHWEST KANSAS INTO CENTRAL NEBRASKA AS A WARM FRONT WITH THE
SURFACE LOW STRENGTHENING. THIS QUASI-STATIONARY FRONT AT 19Z
EXTENDED FROM THE 993MB SURFACE LOW NORTHEAST OF LA JUNTA, COLORADO
TO NEAR GOODLAND, KS TO COLUMBUS, NE. THE SURFACE BAROCLINIC ZONE
WAS VERY IMPRESSIVE WITH A TEMPERATURE OF 17F AT CASPER, WYOMING
NORTH OF THE FRONT IN THE ARCTIC AIRMASS AND 79F AT HAYS, KANSAS.
&&
.SHORT TERM...(THIS EVENING AND OVERNIGHT)
ISSUED AT 336 PM CST SAT NOV 10 2012
THE HIGH WIND EVENT WILL CONTINUE WEST OF THE DRYLINE THROUGH 23Z OR
SO, AT WHICH POINT WINDS WILL SLOWLY SLACKEN OFF WITH DUST SETTLING.
AS FAR AS THE PRECIPITATION CHANCES GO, NO CHANGE IN THE CURRENT
FORECAST IS EXPECTED. DEWPOINT TEMPERATURES HAVE NOT BEEN ANY HIGHER
THAN THE MID 50S, WHICH RESULTED IN CAPE 800-1000 J/KG. DESPITE THE
VERY IMPRESSIVE LOW LEVEL AND DEEP LAYER SHEAR, THE LACK OF
APPRECIABLE INSTABILITY AND LOW LEVEL MOISTURE SHOULD PRECLUDE
WIDESPREAD SEVERE WEATHER. THAT BEING SAID, INTENSE MID LEVEL COLD
ADVECTION WILL BE INCREASING, ALLOWING CAPE PROFILES TO IMPROVE THIS
EVENING. WINDOW FOR SEVERE WEATHER SHOULD BE DURING THE 00-04Z TIME
FRAME, WITH THE LINE OF FORCING AND PACIFIC COLD FRONT MOVING
THROUGH SOUTHWEST KANSAS/WESTERN PORTIONS OF SOUTH CENTRAL KANSAS.
THE CANADIAN COLD FRONT WILL BE MOVING THROUGH DURING THE 09-12Z
TIME FRAME ACROSS SOUTHWEST KANSAS, AT WHICH POINT WE WILL SEE
STRONG COLD AIR ADVECTION WITH -8 TO -11C 850MB TEMPERATURES DRIVING
SOUTH. THERE WILL BE SLIGHT DOWNSLOPE MODIFICATION OF THIS AIRMASS
AS WESTERLY COMPONENT MOMENTUM INCREASES OFF THE ROCKIES OF COLORADO
AND WYOMING. WITH THE ADVECTION OF THE MODIFIED ARCTIC AIRMASS, LOW
STRATUS MAY BE A CONCERN AND WILL BUMP UP THE SKY GRIDS A LITTLE BIT
TO ACCOUNT FOR A LITTLE MORE CLOUD THAN EARLIER THOUGHT WITH THE
INITIAL ONSET OF THE COLD AIR AROUND 09Z OR SO.
.LONG TERM...(SUNDAY THROUGH SATURDAY)
ISSUED AT 336 PM CST SAT NOV 10 2012
COLD AIR WILL INVADE WESTERN KANSAS BEHIND THE FRONT BY EARLY SUNDAY
MORNING. HOWEVER, SOME DOWNSLOPE MODIFICATION ON THE WESTERN EDGE OF THE
COLD AIRMASS WILL ALLOW TEMPERATURES TO RISE INTO THE LOWER TO MID
40S IN MOST LOCATIONS. THE COLDEST NIGHT SO FAR THIS FALL IS EXPECTED
BY SUNDAY NIGHT AS WINDS DECREASE AND CLOUD COVER THINS. LOWS SHOULD
BE IN THE UPPER TEENS TO LOWER 20S BY MONDAY MORNING.
FAIRLY CHILLY AIR WILL PERSIST ON MONDAY AS THE COLD SURFACE HIGH
PRESSURE WILL STILL BE JUST OFF TO THE SOUTHEAST, WITH SEA LEVEL
PRESSURES STILL AROUND 1030MB OVER WESTERN KANSAS. HIGHS SHOULD
ONLY REACH INTO THE UPPER 40S TO LOWER 50S. ANOTHER COLD NIGHT
CAN BE EXPECTED MONDAY NIGHT AS SURFACE HIGH PRESSURE LINGERS TO OUR
EAST. LOWS OUGHT TO BE IN THE 20S.
MAINLY ZONAL MID TO HIGH LEVEL FLOW CAN BE EXPECTED TUESDAY THROUGH
SATURDAY. WEAK LEE TROUGHING WILL DEVELOP IN RESPONSE TO THE
MID-LEVEL DOWNSLOPE FLOW ON TUESDAY AND PERSIST INTO THURSDAY. THIS
WILL LEAD TO SOUTHERLY LOW LEVEL WINDS AND WARMER HIGHS IN THE UPPER
50S AND LOWER 60S. SOME BOUNDARY LAYER DECOUPLING CAN BE EXPECTED
EACH NIGHT GIVEN THE RATHER WEAK PRESSURE GRADIENT. AND GIVEN THE
RELATIVELY DRY AIR AT LOWER LEVELS, TEMPERATURES SHOULD HAVE NO
PROBLEM FALLING INTO THE 30S EACH NIGHT THROUGH FRIDAY. SOME 20S
CANNOT BE RULED OUT IN LOW-LYING AREAS.
A SHORTWAVE TROUGH IS ADVERTISED BY THE VARIOUS MODELS TO APPROACH
THE PLAINS BY LATE FRIDAY INTO SATURDAY. GIVEN THE PROGRESSIVENESS
OF THIS SYSTEM, PRECIPITATION IS NOT LIKELY AS LOW-LEVEL MOISTURE
WILL NOT MAKE IT THIS FAR WEST. HOWEVER, SINCE THE MODELS DO SHOW
SOME MID-LEVEL MOISTURE, ISENTROPIC LIFT AND SMALL AMOUNTS OF QPF,
VERY SMALL CHANCES FOR RAIN WERE MAINTAINED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1150 PM CST SAT NOV 10 2012
1-3.9 MICRON SATELLITE IMAGERY AND METAR OBSERVATIONS INDICATE
WIDESPREAD MVFR STRATUS IS RAPIDLY SPREADING SOUTHWARD ACROSS WEST
CENTRAL KANSAS. THE SOUTHWARD SPEED OF THE LEADIND EDGE INDICATES
THE STRATUS IS LIKELY TO IMPACT THE KGCK AND KDDC TERMINALS BEFORE
08 UTC. THE WIDESPREAD EXTENT OF THE STRATUS SHOULD BE ENOUGH TO
MAINTAIN HIGH CONFIDENCE IN LOW STRATUS THROUGH THE MORNING UNTIL
STRONG INSOLATION BEGINS TO WARM THE LOWER BOUNDARY LAYER.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 31 44 21 52 / 10 0 0 0
GCK 28 43 19 52 / 10 0 0 0
EHA 28 44 21 51 / 10 10 10 0
LBL 30 44 20 52 / 10 10 10 0
HYS 30 42 19 51 / 10 0 0 0
P28 40 46 23 52 / 50 0 10 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...UMSCHEID
SHORT TERM...UMSCHEID
LONG TERM...FINCH
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
328 AM EST SUN NOV 11 2012
.SYNOPSIS...
ISSUED AT 328 AM EST SUN NOV 11 2012
STRONG SOUTH WINDS WILL DEVELOP ACROSS THE REGION TODAY AHEAD OF A
STRONG COLD FRONT. A PUSH OF WARM AIR WILL SEND TEMPERATURES INTO
THE UPPER 60S A MANY LOCATIONS THIS AFTERNOON. SHOWERS WILL DEVELOP
LATE IN THE DAY AND CONTINUE TONIGHT AS THE FRONT MOVES ACROSS THE
AREA. MUCH COLDER AIR ALONG WITH RAIN AND SNOW SHOWERS WILL MOVE
INTO WEST MICHIGAN MONDAY. HIGH TEMPERATURES WILL SLOWLY FALL DURING
THE DAY AND ONLY REACH AROUND 40 DEGREES TUESDAY. MAINLY DRY WEATHER
IS EXPECTED AFTER MONDAY WITH SLOWLY WARMING TEMPERATURES.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EST SUN NOV 11 2012
FORECAST CONCERNS DEAL WITH THE WIND POTENTIAL TODAY AND PCPN TRENDS
TONIGHT/MONDAY.
THE GOING FORECAST IS LARGELY ON TRACK. HOWEVER...WINDS APPEAR A BIT
STRONGER ACROSS THE WRN CWA AS THE GRADIENT TIGHTENS AHEAD OF THE
COLD FRONT. AS SUCH WE ISSUED A WIND ADVISORY FOR THE WRN 1/2 OF THE
CWA. WINDS ARE ALREADY GUSTING TO 36 KTS AT KMKG AND WILL LIKELY
INCREASE A BIT MORE AS THE SUN RISES AND BETTER MIXING OCCURS.
STRONG 65KT LLJ MOVES OVER THE WRN CWA LATE THIS AFTERNOON.
LATEST HRRR HAS A PRETTY GOOD HANDLE ON THE SHOWERS MOVING ACROSS
NRN IL/WISCONSIN. THESE ARE AHEAD OF THE COLD FRONT AND DISSIPATE
SOMEWHAT AS THEY MOVE EWD THIS AFTERNOON. AS A RESULT...WE
ANTICIPATE A DRY DAY. ABUNDANT MID CLOUD WILL BE PRESENT AND THIS
WILL LIMIT MIXING A BIT BUT NOT ENOUGH TO PREVENT SUSTAINED 25 TO 30
MPH WINDS. FROPA IS ON TRACK FOR MIDNIGHT-4AM TIME FRAME. TEMPS WILL
SLOWLY FALL MONDAY AS H8 TEMPS FALL TO -12C. RAIN WILL MIX WITH SNOW
AFTER FROPA THEN BECOME SHSN AS THE THERMAL PROFILE QUICKLY FALLS
BELOW 0C. NOT LOOKING FOR ACCUMS AT THIS POINT. THOUGH IT/S POSSIBLE
A FEW HIGHER ELEVATIONS ACROSS THE NRN CWA COULD SEE A COUPLE OF
TENTHS.
TUESDAY LOOKS DRY BUT CHILLY WITH HIGHS AROUND 40.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EST SUN NOV 11 2012
FOR THE EXTENDED PERIOD...THE CORE OF THE ARCTIC AIR REMAINS WELL
NORTH OF THE REGION. ONE OF THE MAIN REASONS FOR THIS IS THE ZONAL
MID LEVEL FLOW THAT SETS UP ACROSS NORTH AMERICA FOR THE PERIOD.
HERE IN MI...WE WILL SEE ONLY A WEAKENING COLD FRONT ARRIVING THU.
IF THERE IS ANY PRECIPITATION WITH THIS SHALLOW FEATURE...IT WILL BE
LIMITED AS VERY LITTLE MOISTURE AND LIFT WILL BE IN PLACE.
TEMPERATURES AT 850 MB CLIMB THU INTO SAT...SO WE WILL LIKELY SEE A
GENERAL WARMING TREND. ALTHOUGH...GIVEN THE MID LEVEL
FLOW...PACIFIC MOISTURE COULD CAUSE PERIODS OF CLOUDS THAT WOULD
POTENTIALLY LIMIT THE DAYTIME MIXING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1136 PM EST SAT NOV 10 2012
I EXPECT VFR CONDITIONS TO PREVAIL THROUGH EARLY EVENING SUNDAY AS
A STRONG SOUTHERLY FLOW AHEAD OF THE COLD FRONT WILL CONTINUE TO
BRING LOW TO MID LEVEL DRY AIR NORTH. IT WILL BE WINDY TOO.
SURFACE WINDS OF 15 KNOTS WITH GUSTS TO 25 KNOTS ARE EXPECTED
TONIGHT BUT VAD WIND PROFILE IS SHOWING 35 KNOTS AT 2000 FT AND 50
KNOTS AT 3000 FT AGL. I CONTINUED THE LOW LEVEL WIND SHEAR IN THE
TAFS UNTIL THE SUN ALLOWS MIXING OF THE BOUNDARY LAYER... AROUND
15Z. THEN EXPECT 20-30 KNOT WINDS WITH HIGHER GUSTS.
I DO NOT EXPECT THE SHOWERS OVER WISCONSIN LATE THIS EVENING TO
IMPACT THE TAF SITES DUE TO THE MID LEVEL DRY AIR (RAP SOUNDING
SHOW VERY DRY AIR BELOW 15000 FT THROUGH 12Z). THE LINE OF
CONVECTION WITH THE COLD FRONT SHOULD NOT REACH THE TAF SITES
UNTIL 03Z MONDAY NEAR MKG AND WELL AFTER 06Z ON MONDAY AT JXN.
&&
.MARINE...
ISSUED AT 328 AM EST SUN NOV 11 2012
GIVEN THAT WINDS ALONG THE LAKESHORE ARE ALREADY GUSTING NEAR
35KTS...DECIDED TO RUN WITH THE GALE WARNING NOW AND DISCONTINUE THE
SCA. GALES TO 40KTS EXPECTED TODAY WILL BUILD WAVES TO 5 TO 8 FEET.
THE CORE OF THE STRONGER WINDS WILL DIMINISH AFTER 06Z TONIGHT.
&&
.HYDROLOGY...
ISSUED AT 328 AM EST SUN NOV 11 2012
A THIRD OF AN INCH OF PCPN IS EXPECTED AHEAD OF THE COLD FRONT
TONIGHT. THIS SHOULDN/T RESULT IN FLOODING.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WIND ADVISORY FROM 7 AM THIS MORNING TO 3 AM EST MONDAY FOR
MIZ037-038-043-044-050-056-057-064-065-071-072.
LM...GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LMZ844>849.
&&
$$
SYNOPSIS...93
SHORT TERM...93
LONG TERM...MJS
AVIATION...WDM
HYDROLOGY...93
MARINE...93
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1251 AM EST SUN NOV 11 2012
.SYNOPSIS...
A WARM FRONT WILL MOVE FROM SOUTHWEST TO NORTHEAST ACROSS OUR AREA
TONIGHT. THIS FRONT WILL BRING CLOUDS AND LIGHT PRECIPITATION TO
THE AREA...MAINLY AFTER MIDNIGHT. TEMPERATURES WILL BE SUCH THAT
LIGHT MIXED PRECIPITATION IS POSSIBLE...BUT NO ICE OR SNOW
ACCUMULATIONS ARE EXPECTED. THE WARM FRONT WILL BE NORTH OF THE
AREA ON SUNDAY AND A WARMING TREND IS EXPECTED WITH HIGH
TEMPERATURES BY MONDAY ABOUT 15 DEGREES ABOVE NORMAL.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
AS OF 1215 AM EST SUNDAY...PREVIOUS UPDATE HAS HANDLE OF CURRENT
CONVECTION APPROACHING LAKE ONTARIO. DECENT SHOWWALTER AND MOST
UNSTABLE CAPE IN CLOSEST PROXIMITY TO H9 FNT AND STG LLVL JET.
HWVR...THAT SHLD STAY S OF FA AND WEAKEN AS IT MOVES INTO
STABLE...COLDER AIRMASS.
PREVIOUS DISCUSSION...MODEST UPDATES TO SKY COVER AND POPS
THROUGH THE OVERNIGHT HOURS THROUGH MID-MORNING SUNDAY AS OF 930
PM TO ACCT FOR CURRENT TRENDS AND LATEST HRRR DATA. ALL AREAS HAVE
ESSENTIALLY TRENDED CLOUDY AND SHOULD REMAIN SO THROUGH THE
REMAINDER OF THE NIGHT AS WARM FRONT NOW APPROACHING QUICKLY FROM
THE WEST/SOUTHWEST. THUS MINIMUM TEMPERATURES HAVE BEEN REACHED IN
MOST LOCALES WITH STEADY OR SLOWLY RISING VALUES EXPECTED FROM
HERE ON OUT. BLOSSOMING ELEVATED CONVECTION ACROSS SW ONTARIO/LK
HURON INITIALIZED FAIRLY GOOD BY 21-00Z HRRR RUNS AND CORFIDI
VECTOR/STREAMLINE ANALYSIS SUGGESTS THIS ACTIVITY SHOULD STREAK
EAST...ALBEIT IN WEAKENED FORM INTO OUR NRN COUNTIES LATER TONIGHT
INTO TOMORROW MORNING. NO THUNDER AS ELEV INSTABILITY CURRENTLY
DRIVING GREAT LAKES ACTIVITY WILL ERODE BY THE TIME IT GETS HERE.
NONETHELESS HAVE RAISED POPS UPWARD BY 10/20% ACROSS NRN NY AND
LEAST BROUGHT CHC POPS INTO NRN VT ACCORDINGLY. QPF STILL TO
REMAIN LIGHT...BUT COULD SEE SLIGHTLY HIGHER AMTS TO NEAR
0.10-0.15 INCHES ACROSS NRN NY COUNTIES. P-TYPE MAINLY LIQUID AS
WARMER AIR ALOFT STREAMS QUICKLY NORTHEAST...THOUGH A BRIEF PERIOD
OF VERY LIGHT FZRA POSSIBLE ACROSS FAR NERN VT AFTER 08Z. HAVE A
GOOD NIGHT.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH MONDAY NIGHT/...
AS OF 334 PM EST SATURDAY...WE COULD SEE SOME LIGHT MIXED
PRECIPITATION OVER PARTS OF THE NORTHEAST KINGDOM EARLY SUNDAY
MORNING...BUT WARM FRONT QUICKLY LIFTS NORTH OF THE AREA AS UPPER
RIDGE BEGINS TO AMPLIFY OVER THE AREA. BY MIDDAY WE SHOULD SEE DRY
WEATHER AND PLENTY OF SUNSHINE WITH THE AREA IN THE WARM SECTOR.
TEMPERATURES SHOULD ALSO WARM INTO THE 50S MOST LOCATIONS.
PRESSURE GRADIENT WILL STRENGTHEN OVER AREA IN THE AFTERNOON...SO
LOOKING AT SOME GUSTS FROM THE SOUTH AND SOUTHWEST LATE IN THE
DAY...20 TO 30 MPH. PRESSURE GRADIENT STRENGTHENS EVEN MORE ON
MONDAY AS LARGE UPPER TROUGH MOVES TOWARD THE REGION. LOOKING AT
BREEZY TO WINDY CONDITIONS MONDAY AFTERNOON AND EVENING. WARMEST
AIR IN THE LOWER LEVELS MOVES INTO THE REGION WITH HIGHS IN THE
60S...BUT WITH THAT MUCH WIND...IT WILL NOT FEEL THAT WARM.
NEVERTHELESS...THESE TEMPERATURES ARE ABOUT 15 DEGREES ABOVE
NORMAL FOR THIS TIME OF YEAR. THE HIGHER AMPLITUDE UPPER PATTERN
SUGGESTS THAT PRECIPITATION WILL BE CLOSELY TIED TO THE UPPER
TROUGH AXIS AND SURFACE COLD FRONT. AS A RESULT...PRECIPITATION
WILL BE SLOW TO PUSH IN AND EXPECT A DRY DAY ON MONDAY AND INTO
THE FIRST PART OF MONDAY EVENING. RAIN SHOULD THEN SPREAD INTO THE
REGION LATER MONDAY NIGHT...ESPECIALLY AFTER MIDNIGHT. GOING
FORECAST HAS LIKELY TO CATEGORICAL PRECIPITATION CHANCES DURING
THAT TIME PERIOD AND HAVE KEPT THAT THE SAME.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 334 PM EST SATURDAY...THE MAIN WEATHER FEATURE OF INTEREST DURING
THE EXTENDED IS THE COLD FRONT FROM THE PREVIOUS PERIOD. THE
FRONT WILL CONTINUE PROGRESSING EASTWARD ACROSS THE NORTH COUNTRY
TUESDAY. THE PRESENCE OF A LARGE UPPER RIDGE AHEAD OF THE FRONT
AND POTENTIAL FOR NEARLY BOUNDARY-PARALLEL UPPER FLOW SUGGESTS THE
FRONT MAY BE SLOW TO MOVE EASTWARD. STRONG POST-FRONTAL 850/925 MB
COLD ADVECTION WITH 850 MB TEMPERATURES FALLING FROM 10C TO 0-2C
DURING THE AFTERNOON. WOULD EXPECT A NON-DIURNAL TEMPERATURE RANGE
ON TUESDAY WITH HIGHS IN THE 40S TO AROUND 50 LIKELY BEING REACHED
LATE MORNING/EARLY AFTERNOON. PRECIPITATION PROBABILITIES RANGE
FROM LIKELY AHEAD OF THE FRONT ON TUESDAY BEFORE TAPERING QUICKLY
WITH WESTWARD EXTENT. WHILE RAIN IS EXPECTED AHEAD OF THE
FRONT...ANY LIGHT PRECIPITATION THAT OCCURS BEHIND THE FRONT COULD
MIX TO SNOW SHOWERS IN THE NORTHERN ADIRONDACKS AS THERMAL
PROFILES COOL. THE FRONT COULD BE A LITTLE SLOW TO MOVE OUT OF
VERMONT ON TUESDAY NIGHT AS UPPER FLOW BECOMES MORE BOUNDARY-
PARALLEL...SO HAVE CARRIED SLIGHT CHANCE TO CHANCE PRECIPITATION
PROBABILITIES INTO TUESDAY NIGHT.
THE REST OF THE EXTENDED IS RATHER BENIGN AS SFC HIGH PRESSURE
BECOMES ESTABLISHED NORTH OF THE REGION. SEVERAL WEAK MID-LEVEL
SHORTWAVE TROUGHS TRAVERSE THE REGION LATE IN THE WEEK...THOUGH THE
TROUGHS WILL HAVE LIMITED MOISTURE TO WORK WITH. SO WHILE THE
TROUGHS MAY PRODUCE SOME CLOUDS HAVE KEPT THE FORECAST DRY. 850 MB
TEMPERATURES OF -3 TO -6C WEDNESDAY AND THURSDAY RESULT IN HIGHS IN
THE 40S AND LOWS IN THE 20S BOTH DAYS. MODERATING TEMPERATURES ARE
EXPECTED BY LATE WEEK AS 850MB TEMPERATURES RECOVER TO AROUND
0C.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
THROUGH 06Z MONDAY...VFR CONDITIONS EXPECTED THROUGH THE PERIOD. A
WARM FRONT WILL PASS ACROSS THE REGION OVERNIGHT THROUGH SUNDAY
MORNING ACCOMPANIED BY CLOUDS AND SOME VERY LIGHT PRECIPITATION.
HOWEVER...CEILINGS AND VISIBILITIES ARE EXPECTED TO REMAIN VFR AT
ALL TAF SITES. ANY LIGHT PRECIPITATION WHICH DOES OCCUR WILL BE
MAINLY IN THE FORM OF RAIN OR DRIZZLE...HOWEVER A BRIEF PERIOD OF
VERY LIGHT FREEZING RAIN OR SLEET IS POSSIBLE AT SLK/MPV BEFORE
TEMPERATURES RISE OVERNIGHT. GREATEST CHANCE OF PRECIPITATION WILL
OCCUR 08Z-14Z...FOLLOWED BY DRYING WITH CLEARING SKIES THIS
AFTERNOON. SOUTH WINDS WILL BE INCREASING LATER TONIGHT AND INTO
SUNDAY...WITH SOME GUSTS 15-25 KNOTS BY THE AFTERNOON.
OUTLOOK 06Z MONDAY THROUGH THURSDAY...
06Z MONDAY THROUGH 00Z TUESDAY...VFR UNDER RIDGE OF HIGH PRESSURE.
GUSTY SOUTH WINDS LIKELY...ESPECIALLY MONDAY AFTERNOON.
00Z TUESDAY THROUGH 00Z WEDNESDAY...PERIODS OF MVFR/IFR IN RAIN
SHOWERS AS A COLD FRONT MOVES ACROSS THE REGION.
00Z WEDNESDAY ONWARD...VFR UNDER BUILDING HIGH PRESSURE.
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR MONDAY NOVEMBER 12TH:
BURLINGTON - 66 IN 1982
MONTPELIER - 62 IN 1982
ST. JOHNSBURY - 65 IN 1911
MASSENA - 70 IN 1982
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...JMG/SLW
SHORT TERM...EVENSON
LONG TERM...LOCONTO
AVIATION...RJS
CLIMATE...
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1218 AM EST SUN NOV 11 2012
.SYNOPSIS...
A WARM FRONT WILL MOVE FROM SOUTHWEST TO NORTHEAST ACROSS OUR AREA
TONIGHT. THIS FRONT WILL BRING CLOUDS AND LIGHT PRECIPITATION TO
THE AREA...MAINLY AFTER MIDNIGHT. TEMPERATURES WILL BE SUCH THAT
LIGHT MIXED PRECIPITATION IS POSSIBLE...BUT NO ICE OR SNOW
ACCUMULATIONS ARE EXPECTED. THE WARM FRONT WILL BE NORTH OF THE
AREA ON SUNDAY AND A WARMING TREND IS EXPECTED WITH HIGH
TEMPERATURES BY MONDAY ABOUT 15 DEGREES ABOVE NORMAL.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
AS OF 1215 AM EST SUNDAY...PREVIOUS UPDATE HAS HANDLE OF CURRENT
CONVECTION APPROACHING LAKE ONTARIO. DECENT SHOWWALTER AND MOST
UNSTABLE CAPE IN CLOSEST PROXIMITY TO H9 FNT AND STG LLVL JET.
HWVR...THAT SHLD STAY S OF FA AND WEAKEN AS IT MOVES INTO
STABLE...COLDER AIRMASS.
PREVIOUS DISCUSSION...MODEST UPDATES TO SKY COVER AND POPS
THROUGH THE OVERNIGHT HOURS THROUGH MID-MORNING SUNDAY AS OF 930
PM TO ACCT FOR CURRENT TRENDS AND LATEST HRRR DATA. ALL AREAS HAVE
ESSENTIALLY TRENDED CLOUDY AND SHOULD REMAIN SO THROUGH THE
REMAINDER OF THE NIGHT AS WARM FRONT NOW APPROACHING QUICKLY FROM
THE WEST/SOUTHWEST. THUS MINIMUM TEMPERATURES HAVE BEEN REACHED IN
MOST LOCALES WITH STEADY OR SLOWLY RISING VALUES EXPECTED FROM
HERE ON OUT. BLOSSOMING ELEVATED CONVECTION ACROSS SW ONTARIO/LK
HURON INITIALIZED FAIRLY GOOD BY 21-00Z HRRR RUNS AND CORFIDI
VECTOR/STREAMLINE ANALYSIS SUGGESTS THIS ACTIVITY SHOULD STREAK
EAST...ALBEIT IN WEAKENED FORM INTO OUR NRN COUNTIES LATER TONIGHT
INTO TOMORROW MORNING. NO THUNDER AS ELEV INSTABILITY CURRENTLY
DRIVING GREAT LAKES ACTIVITY WILL ERODE BY THE TIME IT GETS HERE.
NONETHELESS HAVE RAISED POPS UPWARD BY 10/20% ACROSS NRN NY AND
LEAST BROUGHT CHC POPS INTO NRN VT ACCORDINGLY. QPF STILL TO
REMAIN LIGHT...BUT COULD SEE SLIGHTLY HIGHER AMTS TO NEAR
0.10-0.15 INCHES ACROSS NRN NY COUNTIES. P-TYPE MAINLY LIQUID AS
WARMER AIR ALOFT STREAMS QUICKLY NORTHEAST...THOUGH A BRIEF PERIOD
OF VERY LIGHT FZRA POSSIBLE ACROSS FAR NERN VT AFTER 08Z. HAVE A
GOOD NIGHT.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH MONDAY NIGHT/...
AS OF 334 PM EST SATURDAY...WE COULD SEE SOME LIGHT MIXED
PRECIPITATION OVER PARTS OF THE NORTHEAST KINGDOM EARLY SUNDAY
MORNING...BUT WARM FRONT QUICKLY LIFTS NORTH OF THE AREA AS UPPER
RIDGE BEGINS TO AMPLIFY OVER THE AREA. BY MIDDAY WE SHOULD SEE DRY
WEATHER AND PLENTY OF SUNSHINE WITH THE AREA IN THE WARM SECTOR.
TEMPERATURES SHOULD ALSO WARM INTO THE 50S MOST LOCATIONS.
PRESSURE GRADIENT WILL STRENGTHEN OVER AREA IN THE AFTERNOON...SO
LOOKING AT SOME GUSTS FROM THE SOUTH AND SOUTHWEST LATE IN THE
DAY...20 TO 30 MPH. PRESSURE GRADIENT STRENGTHENS EVEN MORE ON
MONDAY AS LARGE UPPER TROUGH MOVES TOWARD THE REGION. LOOKING AT
BREEZY TO WINDY CONDITIONS MONDAY AFTERNOON AND EVENING. WARMEST
AIR IN THE LOWER LEVELS MOVES INTO THE REGION WITH HIGHS IN THE
60S...BUT WITH THAT MUCH WIND...IT WILL NOT FEEL THAT WARM.
NEVERTHELESS...THESE TEMPERATURES ARE ABOUT 15 DEGREES ABOVE
NORMAL FOR THIS TIME OF YEAR. THE HIGHER AMPLITUDE UPPER PATTERN
SUGGESTS THAT PRECIPITATION WILL BE CLOSELY TIED TO THE UPPER
TROUGH AXIS AND SURFACE COLD FRONT. AS A RESULT...PRECIPITATION
WILL BE SLOW TO PUSH IN AND EXPECT A DRY DAY ON MONDAY AND INTO
THE FIRST PART OF MONDAY EVENING. RAIN SHOULD THEN SPREAD INTO THE
REGION LATER MONDAY NIGHT...ESPECIALLY AFTER MIDNIGHT. GOING
FORECAST HAS LIKELY TO CATEGORICAL PRECIPITATION CHANCES DURING
THAT TIME PERIOD AND HAVE KEPT THAT THE SAME.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 334 PM EST SATURDAY...THE MAIN WEATHER FEATURE OF INTEREST DURING
THE EXTENDED IS THE COLD FRONT FROM THE PREVIOUS PERIOD. THE
FRONT WILL CONTINUE PROGRESSING EASTWARD ACROSS THE NORTH COUNTRY
TUESDAY. THE PRESENCE OF A LARGE UPPER RIDGE AHEAD OF THE FRONT
AND POTENTIAL FOR NEARLY BOUNDARY-PARALLEL UPPER FLOW SUGGESTS THE
FRONT MAY BE SLOW TO MOVE EASTWARD. STRONG POST-FRONTAL 850/925 MB
COLD ADVECTION WITH 850 MB TEMPERATURES FALLING FROM 10C TO 0-2C
DURING THE AFTERNOON. WOULD EXPECT A NON-DIURNAL TEMPERATURE RANGE
ON TUESDAY WITH HIGHS IN THE 40S TO AROUND 50 LIKELY BEING REACHED
LATE MORNING/EARLY AFTERNOON. PRECIPITATION PROBABILITIES RANGE
FROM LIKELY AHEAD OF THE FRONT ON TUESDAY BEFORE TAPERING QUICKLY
WITH WESTWARD EXTENT. WHILE RAIN IS EXPECTED AHEAD OF THE
FRONT...ANY LIGHT PRECIPITATION THAT OCCURS BEHIND THE FRONT COULD
MIX TO SNOW SHOWERS IN THE NORTHERN ADIRONDACKS AS THERMAL
PROFILES COOL. THE FRONT COULD BE A LITTLE SLOW TO MOVE OUT OF
VERMONT ON TUESDAY NIGHT AS UPPER FLOW BECOMES MORE BOUNDARY-
PARALLEL...SO HAVE CARRIED SLIGHT CHANCE TO CHANCE PRECIPITATION
PROBABILITIES INTO TUESDAY NIGHT.
THE REST OF THE EXTENDED IS RATHER BENIGN AS SFC HIGH PRESSURE
BECOMES ESTABLISHED NORTH OF THE REGION. SEVERAL WEAK MID-LEVEL
SHORTWAVE TROUGHS TRAVERSE THE REGION LATE IN THE WEEK...THOUGH THE
TROUGHS WILL HAVE LIMITED MOISTURE TO WORK WITH. SO WHILE THE
TROUGHS MAY PRODUCE SOME CLOUDS HAVE KEPT THE FORECAST DRY. 850 MB
TEMPERATURES OF -3 TO -6C WEDNESDAY AND THURSDAY RESULT IN HIGHS IN
THE 40S AND LOWS IN THE 20S BOTH DAYS. MODERATING TEMPERATURES ARE
EXPECTED BY LATE WEEK AS 850MB TEMPERATURES RECOVER TO AROUND
0C.
&&
.AVIATION /05Z SUNDAY THROUGH THURSDAY/...
THROUGH 00Z MONDAY...VFR CONDITIONS EXPECTED THROUGH THE PERIOD. A
WARM FRONT WILL PASS ACROSS THE REGION TONIGHT AND SUNDAY MORNING
WITH INCREASING CLOUDS AND SOME VERY LIGHT PRECIPITATION.
HOWEVER...CEILINGS AND VISIBILITIES ARE EXPECTED TO REMAIN VFR AT
ALL TAF SITES. SOME PATCHES OF LIGHT PRECIPITATION ARE POSSIBLE
THIS EVENING...MAINLY IN THE FORM OF LIGHT RAIN OR
DRIZZLE...HOWEVER A BRIEF PERIOD OF VERY LIGHT FREEZING RAIN IS
POSSIBLE AT SLK/MPV BEFORE TEMPERATURES RISE OVERNIGHT. GREATEST
CHANCE OF PRECIPITATION WILL OCCUR AFTER 05Z AND INTO THE FIRST
PART OF SUNDAY MORNING. HOWEVER ASIDE FROM A POSSIBLE VERY BRIEF
PERIOD OF FREEZING RAIN AT SLK/MPV...IT WILL REMAIN LIGHT AND IN
THE FORM OF LIQUID RAIN. ANY REMAINING RAIN SHOWERS WILL COME TO
AN END AFTER 14Z SUNDAY MORNING WITH GENERALLY DRYING AND CLEARING
SKIES BY THE AFTERNOON. SOUTH WINDS WILL BE INCREASING LATER
TONIGHT AND INTO SUNDAY...WITH SOME GUSTS 15-25 KNOTS BY THE
AFTERNOON.
OUTLOOK 00Z MONDAY THROUGH THURSDAY...
00Z MONDAY THROUGH 00Z TUESDAY...VFR UNDER RIDGE OF HIGH PRESSURE.
GUSTY SOUTH WINDS LIKELY...ESPECIALLY MONDAY AFTERNOON. 00Z
TUESDAY THROUGH 00Z WEDNESDAY...PERIODS OF MVFR/IFR IN RAIN
SHOWERS AS A COLD FRONT MOVES ACROSS THE REGION. 00Z WEDNESDAY
ONWARD...VFR UNDER BUILDING HIGH PRESSURE.
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR MONDAY NOVEMBER 12TH:
BURLINGTON - 66 IN 1982
MONTPELIER - 62 IN 1982
ST. JOHNSBURY - 65 IN 1911
MASSENA - 70 IN 1982
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...JMG/SLW
SHORT TERM...EVENSON
LONG TERM...LOCONTO
AVIATION...MUCCILLI
CLIMATE...
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
309 AM EST SUN NOV 11 2012
.SYNOPSIS...
LOW PRESSURE OVER MINNESOTA WILL CONTINUE NORTH INTO CANADA TODAY.
A STRONG COLD FRONT ASSOCIATED WITH THIS LOW WILL SWEEP EAST
ACROSS THE LOCAL AREA ON MONDAY. HIGH PRESSURE WILL THEN BUILD
OVER THE REGION FOR THE REMAINDER OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SOUTHERLY WINDS HAVE STAYED UP OVERNIGHT AND THIS HAS KEPT TEMPS
IN THE MIDDLE 50S MOST AREAS. THE AREA IS NOW COMFORTABLY IN THE
WARM SECTOR AND SEE NO REASON WHY TEMPS WON`T BE A FEW DEGREES
WARMER THAN THEY WERE ON SATURDAY. SOME HIGH CLOUDS WILL
OVERSPREAD THE AREA TODAY BUT THESE SHOULD BE FAIRLY THIN. HAVE
GONE A COUPLE DEGREES ABOVE GUIDANCE AND MUCH OF THE AREA WILL
HAVE A SHOT AT REACHING 70 DEGREES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
NOT MUCH CHANGE TO THE SHORT TERM PERIOD THIS MORNING. MODELS NOW
IN GOOD AGREEMENT BRINGING A STRONG COLD FRONT ACROSS THE AREA ON
MONDAY. THIS FRONT SHOULD REACH THE WESTERN TIP OF THE AREA AROUND
DAYBREAK AND MOVE INTO NW PA BY EARLY AFTERNOON. WILL SEE A LINE
OF SHOWERS ALONG AND BEHIND THIS FRONT AND THE ENTIRE AREA WILL
SEE A SEVERAL HOUR PERIOD OF PRECIPITATION. GIVEN THE TIME OF
DAY...NOT EXPECTING MUCH IF ANY THUNDER WITH THE SHOWERS.
DEWPOINTS COULD POOL INTO THE 50S IN NW PA AND FAR NE OH BEFORE
THE FRONT ARRIVES AND IF ANY AREA HAS A SHOT FOR THUNDER IT COULD
BE THERE. EXPECT CLOSE TO A HALF INCH OF PRECIP MOST AREAS. NEXT
QUESTION IS HOW QUICK THE PRECIP WILL END. IT NOW APPEARS THAT NW
OH AND PORTIONS OF N-CENTRAL OH WILL BE DRY BY LATE TOMORROW
AFTERNOON. HAVE FINE TUNED PRECIP CHANCES. REALISTICALLY...ONLY
ABOUT THE EAST THIRD OF THE AREA HAS A SHOT OF MEASURABLE PRECIP
AFTER 00Z TUE. BY THAT TIME LOW LEVEL THICKNESSES COULD GET COLD
ENOUGH FOR SNOW SHOWERS OR MIXED PRECIP TO THE EAST OF KCLE. ANY
PRECIP THAT FALLS AFTER DARK SHOULD BE FAIRLY LIGHT AND NOT
EXPECTING ANY ACCUMS. BY DAYBREAK TUESDAY 850 MB TEMPS WILL BE
AROUND NEG 8 SO LAKE EFFECT CLOUDS ARE LIKELY IN THE WESTERLY
FLOW. COULD ALSO SEE A FEW SHOWERS EVEN THOUGH THE LOWER
ATMOSPHERE WILL BE FAIRLY DRY. RIDGING WILL MOVE INTO THE AREA
LATER TUESDAY AND THIS SHOULD END THE PRECIP THREAT. TEMPS COULD
SNEAK INTO THE 60S OVER EASTERN AREAS MONDAY AHEAD OF THE FRONT.
THE REST OF THE PERIOD WILL SEE BELOW NORMAL TEMPS. HAVE STAYED
PRETTY CLOSE TO GUIDANCE MOST PERIODS.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
MODELS CONTINUE TO BE IN REASONABLE AGREEMENT IN THE LONG TERM WITH
HIGH PRESSURE ANCHORED OVER THE GREAT LAKES. MODELS MOVE LOW
PRESSURE SYSTEM ACROSS THE LOWER TENNESSEE VALLEY LATE IN THE WEEK
AND THEN UP THE EAST COAST THIS WEEKEND. ALTHOUGH EXACT TRACK AND
TIMING OF LOW OFF SOMEWHAT BOTH MODELS HAVE THE LOW OFF THE VIRGINIA
COAST BY SUNDAY AFTERNOON. AT THIS POINT HIGH SEEMS STRONG ENOUGH
THAT WILL KEEP FORECAST DRY THROUGH THE ENTIRE FORECAST PERIOD.
TEMPS CONTINUE TO SHOW A VERY GRADUAL WARMING TREND.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
LOOKING AT WINDS AND TEMPS...BEST FIT FOR WARM FRONT PLACEMENT
TAKES IT FROM CENTRAL LWR MI ESE ACROSS LAKE ERIE INTO NERN OHIO.
WINDS AT KERI ARE FRONT 060 DEGREES AND KCLE AND KYNG HAVE BACKED
10 TO 30 DEGREES OVER THE PAST COUPLE HOURS SO FRONT MAY BE
WAFFLING A BIT INTO THE AREA. A QUICK LOOK AT THE HRRR HIGH REZ
WIND FORECAST SUGGESTS THIS STOPS AND REVERSES OVER THE NEXT
COUPLE HOURS TURNING WINDS AT KERI BACK TO SOUTHERLY. HAVE ALSO
SEEN DEVELOPMENT OF A CIG AROUND 45 HUNDRED FEET AT KERI AND
SATELLITE SHOWS A SIMILAR DECK DEVELOPING IN VICINITY OF KCLE AS
WELL. WILL CARRY THIS FOR THE NEXT FEW HOURS BUT WITH THE WARM
FRONT BEGINNING TO MOVE NORTH AGAIN WILL NOT CARRY THROUGH THE
NIGHT. OTHER THAN THAT EXPECT ONLY CONVECTIVE DEBRIS CLOUDS
100-120 FEET TO AFFECT TERMINALS OVERNIGHT. SUNDAY...THROUGH THE
DAY EXPECT VFR CONDITIONS BUT WINDS WILL INCREASE TO AROUND 15
KNOTS GUSTING INTO THE MID 20 KNOT RANGE KCLE AND POINTS WEST.
FURTHER EAST GUSTS TO NEAR 20.
OUTLOOK...NON-VFR DEVELOPING IN SHOWERS MONDAY THROUGH MONDAY
EVENING ALONG WITH GUSTY WINDS...LINGERING NON VFR NE OH/NW PA ON
TUESDAY.
&&
.MARINE...
SOUTH FLOW WILL BECOME BREEZY THIS AFTERNOON...BUT AS COLD AS THE
LAKE IS DO NOT THINK A LOT OF THE WIND WILL MIX DOWN TO THE LAKE
ITSELF. THEREFORE WILL NOT GO WITH A SMALL CRAFT ADVISORY TODAY. A
SMALL CRAFT WILL LIKELY BE NEEDED TONIGHT. MODELS CONTINUE TO BE IN
GOOD AGREEMENT ON THE TIMING OF THE STRONG COLD FRONT MONDAY. WINDS
TURN TO THE WEST AND INCREASE TO 30 KNOTS MONDAY AS THE FRONT MOVES
ACROSS THE LAKE. THE 850MB TEMPS DIP TO MINUS 10C BY TUESDAY.
SMALL CRAFT LIKELY UNTIL LATE TUESDAY AS HIGH PRESSURE MOVES OVER
THE LAKE. AFTER THAT HIGH PRESSURE WILL BE DOMINATE FEATURE INTO
NEXT WEEKEND.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KUBINA
NEAR TERM...KUBINA
SHORT TERM...KUBINA
LONG TERM...DJB
AVIATION...TK
MARINE...DJB
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1149 PM CST SAT NOV 10 2012
.UPDATE...
&&
.AVIATION...
CONVECTION CONTINUES TO DEVELOP ACROSS THE WESTERN PORTIONS OF
THE BIG COUNTRY LATE THIS EVENING...BUT APPEARS THAT THE VAST
MAJORITY WILL TRACK NORTH AND WEST OF ABILENE...KABI. WILL
CONTINUE THE VCTS MENTION...AS THE MAIN AREA OF LIFT LIFTS TO THE
NORTHWEST. PACIFIC FRONT MOVING INTO THE AREA WILL KEEP SOME
CHANCE OF STORMS THROUGH THE OVERNIGHT HOURS...AGAIN...MAINLY NEAR KABI.
OTHERWISE...BREEZE SOUTH WINDS TO CONTINUE OVERNIGHT...AND WILL
LIKELY SEE A FEW STRATUS...BUT MAY ACTUALLY HAVE A HARD TIME
FORMING ANYTHING MORE THAN A BRIEF CIG. COLD FRONT MOVES QUICKLY
THROUGH ON SUNDAY...BRINGING DRIER CONDITIONS ON STRONG WEST WINDS.
&&
.PREV DISCUSSION... /ISSUED 905 PM CST SAT NOV 10 2012/
UPDATE...
NO CHANGES.
DISCUSSION...
SURFACE TROUGH AND COLD FRONT EXTENDED FROM WINK NORTHEAST TO
LUBBOCK...THEN INTO NW OKLAHOMA. SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS HAD DEVELOPED EAST OF THE FRONT IN THE PERMIAN
BASIN AND SE TEXAS PANHANDLE.
SCATTERED SHOWERS STILL EXPECTED TO MOVE INTO EASTERN SECTIONS OF
WEST CENTRAL TEXAS AFTER MIDNIGHT...AS UPPER TROUGH IN THE ROCKY
MOUNTAINS MOVES EAST. RUC MUCAPES ON SPC MESOSCALE ANALYSIS PAGE
FOR WEST CENTRAL TEXAS...WERE ON THE LOWER SIDE FOR SEVERE
STORMS...IN THE 500 TO 800 J/KG RANGE...BUT 0-6 KM SHEAR WAS
QUITE HIGH AT OVER 50 KTS. THUS WHILE A STRONG STORM OR EVEN
SEVERE STORM POSSIBLE...MOST SHOULD REMAIN BELOW SEVERE LIMITS.
MAIN POTENTIAL FOR SEVERE WEATHER TONIGHT...MAY BE DAMAGING WINDS
..IF THE STRONG WINDS ASSOCIATED WITH THE 50-60 KT LOW LEVEL JET
PARTIALLY MIX TO GROUND LEVEL WITH PRECIPITATION.
FORECAST LOOKS TO BE IN GOOD SHAPE...THUS WILL NOT MAKE CHANGES
AT THIS TIME.
PREV DISCUSSION... /ISSUED 520 PM CST SAT NOV 10 2012/
UPDATE...
SEE 00Z AVIATION DISCUSSION BELOW.
AVIATION...
VFR CONDITIONS TO PREVAIL THE MAJORITY OF THE TIME ACROSS WEST
CENTRAL TEXAS TERMINALS. STARTING TO SEE A FEW SHOWERS DEVELOP
ACROSS THE SOUTH PLAINS...AND THESE SHOULD GRADUALLY MOVE EAST AND
INCREASE IN COVERAGE SOME THROUGH THE OVERNIGHT HOURS. BETTER
CHANCES ACROSS THE BIG COUNTRY...WITH THE ABILENE...KABI...
TERMINAL THE MOST LIKELY TO SEE ONE OF THESE STORMS.
STILL...TIMING AND COVERAGE REMAINS A QUESTION...SO WILL NOT
INCLUDE ANYTHING MORE THAN A VCTS.
OTHERWISE...BREEZE SOUTH WINDS TO CONTINUE OVERNIGHT...AND WILL
LIKELY SEE A FEW STRATUS...BUT MAY ACTUALLY HAVE A HARD TIME
FORMING ANYTHING MORE THAN A BRIEF CIG. COLD FRONT MOVES QUICKLY
THROUGH ON SUNDAY...BRINGING DRIER CONDITIONS ON STRONG WEST WINDS.
PREV DISCUSSION... /ISSUED 359 PM CST SAT NOV 10 2012/
SHORT TERM...
UPPER LEVEL TROUGH MOVING ACROSS THE ROCKIES THIS AFTERNOON...WITH
MODELS SHOWING THE BEST SYNOPTIC LIFT MOVING ACROSS THE BIG COUNTRY
NORTHWARD INTO OKLAHOMA AND KANSAS LATER THIS EVENING. MAIN SURFACE
LOW WELL NORTH...BUT DRYLINE HAS TRIED TO BECOME ESTABLISHED SOUTH
THROUGH MUCH OF WEST TEXAS. ATMOSPHERE HAS BEEN CAPPED SO FAR AHEAD
OF THIS DRYLINE...BUT APPROACHING LIFT SHOULD BE ABLE TO ERODE THIS
CAP THIS EVENING. STILL LOOKS LIKE MOST OF THE CONVECTION WILL BE
FARTHER NORTH...WITH THE TAIL END ACROSS THE BIG COUNTRY AND PERHAPS
AS FAR SOUTH AS THE CONCHO VALLEY. ONCE STORMS DEVELOP...SHOULD
SOLIDIFY INTO A MORE SOLID AREA AS LOW LEVEL JET OF 50 KNOTS
DEVELOPS.
PACIFIC FRONT OVERTAKES THE DRYLINE AND PUSHES QUICKLY ACROSS WEST
CENTRAL TEXAS BETWEEN 12Z AND 18Z ON SUNDAY. WILL CONTINUE THE
CHANCE OF STORMS THROUGH THE MORNING HOURS WITH CONVECTION STILL
LIKELY ONGOING ACROSS THE AREA...WITH A MUCH DRIER AIR MASS
FOLLOWING THE FRONT FOR THE AFTERNOON. BREEZY WEST WINDS...WHICH ARE A
DOWNSLOPE...WILL OFFSET A LITTLE OF THE COLD ADVECTION...AND WILL
KEEP TEMPERATURES ON THE WARM SIDE OF GUIDANCE.
FIRE WEATHER CONCERNS WILL ALSO NEED TO BE MONITORED SUNDAY
AFTERNOON...AS HUMIDITY AND WIND CONDITIONS MAY APPROACH RED FLAG
CRITERIA. HOWEVER...RECENT RAINFALL HAS ACTUALLY ALLOWED FOR A
LITTLE BETTER VEGETATION. NEXT SHIFT WILL NEED TO MONITOR...BUT WILL
HOLD OFF ON ANY HIGHLIGHTS FOR NOW.
07
FOR THE REMAINDER OF THE SHORT TERM...THROUGH TUESDAY...LOOK FOR
UNSEASONABLY COLD TEMPERATURES. THE NAM AND GFS ARE IN VERY GOOD
AGREEMENT THIS CYCLE. OVERNIGHT TOMORROW NIGHT...TEMPERATURES AT
850 MB WILL RANGE FROM AROUND 2 CELSIUS ACROSS THE NORTHERN BIG
COUNTRY TO AROUND 5 CELSIUS AROUND OUR SOUTHERN COUNTIES.
PLUS...SURFACE WINDS TOMORROW NIGHT WILL BE VERY LIGHT TO PERHAPS
CALM...AS SURFACE HIGH PRESSURE DOMINATES TEXAS. THESE TWO
FACTORS...ALONG WITH CLEAR SKIES AND ASSOCIATED RADIATIONAL
COOLING...WILL PRODUCE LOWS SUNDAY NIGHT AROUND 30. DURING THE
DAY MONDAY...THE SURFACE HIGH WILL SLIDE EAST...AND SOUTHERLY
SURFACE RETURN FLOW WILL DEVELOP. HOWEVER...850 MB TEMPERATURES DO
NOT REBOUND MUCH DURING THE DAY. THUS...AFTERNOON HIGHS MAINLY IN
THE 55 TO 60 RANGE AND WELL BELOW SEASONAL NORMALS LOOK LIKELY.
OVERNIGHT MONDAY NIGHT...RADIATIONAL COOLING AND LIGHT WINDS WILL
AGAIN PRODUCE LOWS BELOW THE FREEZING MARK...WITH SOME AREAS
LIKELY FALLING INTO THE MID 20S HARD-FREEZE RANGE. FOR
TUESDAY...850 MB TEMPERATURES BEGIN TO REBOUND SLIGHTLY. WITH LOTS
OF SUNSHINE TUESDAY...I EXPECT AFTERNOON HIGHS VERY CLOSE TO MEX MOS
GUIDANCE NUMBERS...MAINLY IN THE 60 TO 65 RANGE.
HUBER
LONG TERM...
TEMPERATURES CONTINUE A SLOW REBOUND INTO THE START OF NEXT
WEEKEND. ALOFT...THE PATTERN SHIFTS FROM A BROAD RIDGE TO MAINLY
ZONAL FLOW. AT THE SURFACE...SOUTHERLY FLOW DOMINATES THE BOUNDARY
LAYER...AND SURFACE DEWPOINT TEMPERATURES RETURN TO THE MID TO
UPPER 50S BY FRIDAY AFTERNOON. TEMPERATURE NUMBERS CLOSE TO MEX
MOS GUIDANCE LOOK GOOD...WITH AFTERNOON HIGHS WELL ABOVE SEASONAL
NORMALS FOR SATURDAY.
HUBER
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 58 70 31 54 29 / 30 20 5 5 0
SAN ANGELO 59 71 31 58 29 / 20 20 5 5 0
JUNCTION 61 75 29 61 28 / 10 30 5 5 0
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
343 AM CST SUN NOV 11 2012
.SHORT TERM...
TODAY-FORECAST CONFIDENCE HIGH
STRONG DYNAMIC SETUP COMING UP TODAY. DEEP UPPER TROUGH IN THE
ROCKIES PUSHES OUT INTO THE PLAINS WITH STRONG HEIGHT FALLS THIS
AFTERNOON. 500 MB 12 HOUR FALLS OF 60 TO 80 METERS SPREAD INTO
SOUTHERN WISCONSIN DURING THE AFTERNOON AS SURFACE COLD FRONT
APPROACHES.
ALTHOUGH SURFACE LOW NOT EXPECTED TO DEEPEN AS IT LIFTS INTO
NORTHWEST ONTARIO...VERY STRONG AND DEEP FRONTOGENESIS SHOWN BEHIND
SURGING COLD FRONT. THIS FRONT SHOULD ENTER FAR WEST AROUND NOON
AND THEN PROBABLY JUST EAST OF A LINE FROM FLD TO RFD BY 00Z MON.
BRIEF PERIOD OF NEAR WIND ADVISORY CONDITIONS ALREADY OCCURRED WITH
EARLIER 65 KNOT 850 MB WIND MAX THAT PUSHED THROUGH. MODELS SHOW A
LULL IN LOW LEVEL JET THEN A NEW NARROW SURGED SHOWN JUST AHEAD OF
THE FRONT LATER THIS MORNING INTO THIS AFTERNOON. GFS SHOWS UP TO
80 KNOTS AT 850 MB OVER SHEBOYGAN BY LATE AFTERNOON. WITH MEAN WIND
IN SURFACE TO 850 MB LAYER OF NEARLY 60 KNOTS...CERTAINLY CONCERN
FOR STRONG WIND GUSTS SO WILL GO WITH WIND ADVISORY FOR THE CENTRAL
AND EASTERN PORTIONS OF THE CWA. HRRR SURFACE GUST POTENTIAL
INDICATES 40 KNOTS AND GFS BUFKIT SHOWING SIMILAR GUST POTENTIAL
ESPECIALLY TOWARD THE LAKE SHORE.
RAIN SHOULD SPREAD EAST ALONG WITH A FEW RUMBLES OF THUNDER AND MAY
NOT QUITE REACH LAKE SHORE BY 00Z.
TONIGHT-FORECAST CONFIDENCE HIGH
CONTINUED CRASHING OF UPPER HEIGHTS AS FULL LATITUDE TROUGH CRASHES
THROUGH THE MISSISSIPPI RIVER VALLEY. 500 MB 12 HOUR FALLS OF 180
METERS SPREAD ACROSS SOUTHERN WISCONSIN...HELPING USHER IN MUCH
COLDER AIR.
WINDS SHOULD DIE DOWN BEHIND COLD FRONT SO WILL LET WIND ADVISORY
EXPIRE IN THE WESTERN AREAS AT 00Z AND 02Z IN THE EAST PER
COORDINATION WITH DVN AND LOT WFOS.
RAIN SHOULD END PRIOR TO AIR COOLING ENOUGH FOR CHANGE OVER TO
SNOW. HOWEVER...HAVE A CHANCE OF LIGHT SNOW AT THE TAIL END OF THE
PRECIPITATION BUT GUT FEELING IS THAT PROBABLY IS PRETTY LOW.
ALMOST ALL OF THE GUIDANCE SHOWS THE PRECIP CUTTING OFF RIGHT ABOUT
THE TIME THAT THE 850 MB TEMPERATURE CRASHES TO ZERO OR COLDER.
TREMENDOUS COLD ADVECTION SHOULD DROP WESTERN AREAS INTO THE LOWER
20S BY MORNING DESPITE CLOUD COVER WITH CONSENSUS 850 MB TEMPS DOWN
TO -10C BY 12Z MONDAY.
MONDAY THROUGH MONDAY NIGHT...FORECAST CONFIDENCE MEDIUM.
IT WILL BE A COLD...DRY AND MOSTLY CLOUDY MONDAY. EXPECT CLEARING
BEHIND THE FRONT TO LAST INTO MONDAY MORNING AND THEN INSTABILITY
CLOUDS WITH THE STEEP LOW LEVEL LAPSE RATES IN THE CYCLONIC FLOW
REGIME WILL QUICKLY DEVELOP LATE IN THE MORNING. FLURRIES ARE
POSSIBLE WITH THE AFTERNOON LOW CLOUDS. WINDS WILL BE BRISK OUT OF
THE WEST 15 TO 20 MPH WITH HIGHER GUSTS. MAX TEMPS WILL WILL BE IN
THE LOWER 30S...WITH A FEW LOCATIONS EXPECTED TO STAY BELOW FREEZING.
LINGERING TIGHT PRESSURE GRADIENT ABOVE THE SURFACE WILL ONLY ALLOW
FOR A WEAK INVERSION...THUS KEEPING MIN TEMPS IN CHECK. WITH 925MB
TEMPS AROUND -4C...EXPECT LOWS IN THE LOWER 20S. A FEW LOCATIONS MAY
SEE LOWS IN THE TEENS.
TUESDAY THROUGH THURSDAY...FORECAST CONFIDENCE IS MEDIUM TO HIGH.
HIGH PRESSURE WILL RETURN AND BRING DRY WEATHER FOR MUCH OF THE
REMAINDER OF THIS WEEK. 500MB PATTERN WILL BECOME ZONAL OVER THE
NORTHERN PLAINS AND UPPER GREAT LAKES. A SMALL RIPPLE IN THE FLOW
MAY BRING LIGHT RAIN TO WI TUE NIGHT/WED...BUT IT LOOKS LIKE IT JUST
MIGHT BE INCREASING CLOUDS WITH ISENTROPIC LIFT/WARM AIR ADVECTION.
THE LOW LEVELS ARE EXPECTED TO BE TOO DRY TOO ALLOW FOR ANY
MEASURABLE PRECIP. DRY FORECAST FOR SOUTHERN WI CONTINUES.
TEMPS WILL GRADUALLY WARM THROUGH THE WEEK...BEGINNING AROUND 40 ON
TUESDAY AND ENDING UP AROUND 50 FOR THE WEEKEND.
.LONG TERM...
NEXT WEEKEND...FORECAST CONFIDENCE MEDIUM.
MODELS TRENDED AWAY FROM PRECIP CHANCES IN SOUTHERN WISCONSIN OVER
THE WEEKEND. IT LOOKS LIKE BLOCKING HIGH PRESSURE WILL BE IN CONTROL
WITH DRY WEATHER THROUGH EARLY NEXT WEEK. MAX TEMPS WILL BE AROUND
50.
&&
.AVIATION/12Z TAFS/...
LOW LEVEL SHEAR EARLY THIS MORNING WITH 55 KNOTS AT 2000 FEET AGL
SHOULD RELAX AS SURFACE WINDS INCREASE.
GUSTY SOUTH WINDS TO 35 OR 40 KNOTS EXPECTED ESPECIALLY AT KMKE AND
KENW THIS AFTERNOON AND EARLY EVENING AHEAD OF STRONG COLD FRONT.
PERIOD OF IFR CEILINGS AND VISIBILITIES IN MODERATE TO BRIEFLY HEAVY
RAIN AND RUMBLE OF THUNDER EXPECTED JUST BEHIND COLD FRONT THIS
AFTERNOON IN KMSN AND IN SOUTHEAST TAF SITES LATE AFTERNOON AND
EVENING.
WINDS SHIFT TO WEST AND DIMINISH RAPIDLY BEHIND COLD FRONT THIS
EVENING. CEILINGS SHOULD IMPROVE TO MVFR AFTER RAIN ENDS DURING THE
EVENING AND THEN EVENTUALLY TO VFR AFTER MIDNIGHT AS COLDER AND
DRIER AIR MOVES IN.
NOT IMPOSSIBLE FOR RAIN TO END AS BRIEF PERIOD OF WET SNOW OR SLEET
AT KMSN DURING THE EVENING...BUT NOT MUCH IMPACT EXPECTED WITH
SLIGHTLY ABOVE FREEZING TEMPERATURES.
&&
.MARINE...
ALREADY GUSTING NEAR GALE FORCE EARLY THIS MORNING AT KENOSHA HARBOR
AND EXPECT GALE FORCE SOUTHERLY GUSTS LATER THIS MORNING AND THIS
AFTERNOON AHEAD OF STRONG COLD FRONT. THUS GALE WARNING FOR MID
MORNING INTO THE EVENING LOOKS GOOD.
WINDS SHIFT TO WEST AND DIMINISH RAPIDLY AFTER COLD FRONTAL PASSAGE
THIS EVENING. DUE TO HIGH WAVES AND BRISK WEST WINDS...WILL LIKELY
NEED TO DOWNGRADE GALE TO SMALL CRAFT ADVISORY THIS EVENING AND RUN
IT THROUGH MONDAY. WAVES WILL DIMINISH WITH OFFSHORE FLOW BUT
WESTERLY GUSTS TO 25 KNOTS EXPECTED DUE TO UNSTABLE CONDITIONS WITH
STRONG COLD ADVECTION CONTINUING BEHIND FRONT LATE TONIGHT AND
MONDAY.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...WIND ADVISORY FROM 10 AM THIS MORNING TO 6 PM CST THIS EVENING
FOR WIZ051-057-058-063-064-068-069.
WIND ADVISORY FROM 10 AM THIS MORNING TO 8 PM CST THIS EVENING
FOR WIZ052-059-060-065-066-070>072.
LM...SMALL CRAFT ADVISORY UNTIL 10 AM CST THIS MORNING FOR LMZ643>646.
GALE WARNING FROM 10 AM THIS MORNING TO 9 PM CST THIS EVENING
FOR LMZ643>646.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...CRAVEN
MONDAY THROUGH SATURDAY...MRC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
313 AM CST SUN NOV 11 2012
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
313 AM CST SUN NOV 11 2012
THE MAIN FOCUS THROUGH EARLY NEXT WEEK IS WITH THE CHANGE OVER
FROM RAIN TO FROZEN PRECIPITATION TODAY AND HOW COLD IT WILL BE
THE NEXT FEW DAYS.
BROAD UPPER LEVEL TROUGHING HAS MOVED INTO THE CENTRAL PLAINS AND
UPPER MISSISSIPPI RIVER VALLEY WITH THE MAIN EMBEDDED CLOSED LOW
CURRENTLY LOCATED IN NORTHEAST MONTANA. AT THE SURFACE...A LOW
PRESSURE SYSTEM HAS MADE IT INTO NORTHERN MINNESOTA WITH A COLD
FRONT TRAILING TO THE SOUTH ALONG AND JUST TO THE WEST OF I-35
FROM MINNESOTA DOWN TO NORTHWEST MISSOURI. HIGH TEMPERATURES HAVE
LIKELY ALREADY BEEN HIT FOR THE DAY WITH COLDER AIR MOVING IN THIS
MORNING. TWO MAIN CORRIDORS OF RAIN SHOWERS AND ISOLATED
THUNDERSTORMS HAVE SET UP WITH ONE EASTERN BAND IN WISCONSIN BEING
IN THE MIDDLE OF THE STRONGEST LOW LEVEL MOISTURE TRANSPORT AND
THE OTHER ASSOCIATED WITH THE SURFACE COLD FRONT. INSTABILITY IS
RATHER LIMITED WITH 11.07Z RAP ANALYSIS SHOWING LESS THAN 250 J/KG
ACROSS THE ENTIRE AREA...SO THUNDERSTORMS SHOULD REMAIN FAIRLY
ISOLATED.
WITH THE EASTERN BAND OF RAIN BEING TO THE EAST OF THE FORECAST
AREA...THE FOCUS IS MORE SO WITH THE WESTERN BAND THAT WILL MOVE IN
ALONG WITH THE COLD FRONT THIS MORNING. 11.00Z NAM/GFS CROSS
SECTIONS RUNNING FROM WEST TO EAST ACROSS THE REGION SHOW
INCREASING FRONTOGENESIS WITH DEEPER LIFT COMING IN AS A RESULT
THIS MORNING ALONG AND BEHIND THE FRONT. WOULD EXPECT THE SCATTERED
COVERAGE TO THE RAIN TO BECOME MORE WIDESPREAD BY MID MORNING.
WITH A PROLONGED PERIOD OF RAIN LASTING THROUGH MUCH OF
TODAY...EXPECT TO SEE RAINFALL AMOUNTS RANGING FROM AROUND A HALF
INCH ON UP TO AN INCH AND A HALF WITH THE HIGHER AMOUNTS MORE
LIKELY ACROSS WESTERN WISCONSIN.
WITH MUCH OF THE PRECIPITATION OCCURRING AFTER THE SURFACE COLD
FRONT COMES THROUGH...IT APPEARS LIKELY THAT TEMPERATURES WILL BE
ABLE TO COOL QUICKLY ENOUGH THAT A CHANGE OVER TO FROZEN
PRECIPITATION WILL OCCUR. 11.00Z NAM/GFS AND 11.06Z RAP SOUNDINGS
SHOW A RAPID NEAR SURFACE LAYER COOLING BEHIND THE FRONT WHILE A
WARM LAYER REMAINS AROUND 850MB. THIS COULD LEAD TO A BRIEF
TRANSITION PERIOD WHERE THE WARM LAYER WILL BE WARM ENOUGH AT +2
TO +4C WITH A NEAR SURFACE COLD LAYER DROPPING DOWN TO AROUND -7C
THAT SOME SLEET AND/OR FREEZING RAIN MAY OCCUR. THE WARM LAYER
RAPIDLY COOLS THOUGH AND CATCHES UP TO WHERE THE FULL THERMAL
PROFILE IS SUB-FREEZING WHILE PRECIPITATION IS STILL OCCURRING.
THIS PERIOD OF ALL SNOW APPEARS TO BE BRIEF AS WELL AT AN HOUR TO
3 HOURS OR SO BEFORE DRIER AIR MOVES IN AND ENDS THE PRECIPITATION.
GIVEN THE SHORT RESIDENCE TIME OF THE FROZEN PRECIPITATION...AM
NOT EXPECTING MUCH IN THE WAY OF ACCUMULATION OF SNOW WITH UP TO A
HALF INCH FALLING. IMPACTS FROM ANY SLEET OR FREEZING RAIN ARE
EXPECTED TO BE MINIMAL AFTER A PROLONGED PERIOD OF RAIN FALLING
BEFORE IT THOUGH SOME SLICK SPOTS CAN NOT BE COMPLETELY RULED OUT.
A COOL CANADIAN AIR MASS WITH THEN DROP DOWN INTO THE REGION
SUNDAY NIGHT INTO MONDAY WITH 850MB TEMPERATURES DROPPING DOWN TO
AROUND -16C BY MONDAY MORNING. WITH SOME BRIEF CLEARING EXPECTED
OVERNIGHT ACROSS NORTHEAST IOWA...COULD SEE SOME SPOTS DROP INTO
THE TEENS. HIGH TEMPERATURES WILL THEN STRUGGLE TO GET ABOVE
FREEZING ON MONDAY WITH THE CORE OF THE COLDEST AIR OVERHEAD ALONG
WITH CLOUDY SKIES. WITH THE LOW LEVEL MOISTURE BEING IN THE
DENDRITIC GROWTH ZONE BUT LIFT BEING WEAK...EXPECT TO SEE FLURRIES
THROUGH MUCH OF THE DAY BEFORE THE TROUGH PROPAGATES TO THE EAST
INTO THE GREAT LAKES. A GRADUAL WARMING TREND WILL THEN KICK OFF
ON TUESDAY WITH LOW LEVEL SOUTHWESTERLY WINDS BRINGING WARMER AIR
INTO THE REGION. THE 11.00Z GFS/ECMWF DO SHOW SOME PRECIPITATION
FORMING ALONG THE NORTHERN FRINGE OF THE LOW LEVEL ADVECTION
TUESDAY NIGHT WHICH SHOULD REMAIN TO THE NORTHWEST OF THE FORECAST
AREA.
.LONG TERM...WEDNESDAY THROUGH SATURDAY
313 AM CST SUN NOV 11 2012
HIGH PRESSURE SETS UP ACROSS THE EASTERN HALF OF THE US ON
WEDNESDAY AND LINGERS THROUGH NEXT WEEKEND AND SHOULD LEAVE DRY
CONDITIONS THROUGH THE PERIOD. WITH THE UPPER MISSISSIPPI RIVER
VALLEY BEING ON THE WESTERN PERIPHERY OF THE RIDGE THERE SHOULD BE
SOUTHERLY SURFACE TO LOW LEVEL WINDS THAT WILL KEEP TEMPERATURES
AT ABOUT NORMAL.
&&
.AVIATION...THROUGH 06Z MONDAY
1127 PM CST SAT NOV 10 2012
COLD FRONT IS CURRENTLY BISECTING MINNESOTA FROM NORTH TO SOUTH.
TAF SITES REMAIN IN THE WARM SECTOR...WHERE CEILINGS WERE
GENERALLY 040K FEET AND HIGHER ALONG WITH A FEW SPRINKLES.
PRESSURE GRADIENT RATHER TIGHT AND BUFKIT SOUNDINGS STILL
SHOWING HIGHER WINDS ALOFT AT 55 TO 60 KNOTS AND THUS CONTINUED
THE LLWS. COLD FRONT POISED TO PUSH THROUGH KRST BETWEEN 12Z-15Z
AND KLSE 15Z-18Z. AS THE FRONT APPROACHES...EXPECT RAIN TO BECOME
MORE WIDESPREAD AND CEILINGS TO LOWER INTO THE IFR CATEGORY AT
BOTH SITES WITH IFR TO LOWER MVFR CEILINGS REMAINING THROUGH MUCH
OF THE DAY. THE RAIN WILL MIX WITH SNOW BEFORE THE PRECIPITATION
ENDS AND LOOKING AT A FEW HOUR WINDOW OF THE MIXED
PRECIPITATION...GENERALLY AROUND 19Z-21Z AT KRST AND AFTER 22Z AT
KLSE. PRECIPITATION WILL END SHORTLY AFTER 00Z FROM WEST TO EAST
WITH MVFR CEILINGS REMAINING THROUGH 06Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
313 AM CST SUN NOV 11 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS LINCOLN IL
524 AM CST SUN NOV 11 2012
.DISCUSSION...
ISSUED 246 AM CST SUN NOV 11 2012
BIGGEST CHALLENGES THIS PACKAGE ARE WINDS TODAY/THIS EVENING AND
MODEL SPREAD TOWARD THE END OF THE WEEK.
SHORT TERM...TODAY AND TONIGHT
LOOKS LIKE A WINDY DAY ACROSS CENTRAL AND SOUTHEAST ILLINOIS.
THERE IS SOME SPREAD IN FORECAST WIND SPEEDS. STRONGER NAM SEEMS
MORE REASONABLE GIVEN MATCHING UP CURRENT WINDS AND THE HIGHER
RESOLUTION IN THE BOUNDARY LAYER COMPARED TO THE GLOBAL MODELS.
FORECAST GRADIENT WINDS SUGGEST SUSTAINED SPEEDS SHOULD SURPASS
ADVISORY LEVELS. EVEN THOUGH THE GFS GRIDS DO NOT INDICATED AS
HIGH OF SPEEDS AS THE NAM AND HIGH RES MODELS...MAV GUIDANCE IS
INDICATING ADVISORY CRITERIA. NAM MODEL SOUNDINGS SHOW 40+ KTS
SEVERAL HUNDRED FEET OFF THE SURFACE AND SUFFICIENT MIXING OCCURS...THE
GUST CRITERIA OF 45 KTS MAY ALSO BE SURPASSED. CLOUDS MAY LIMIT
MIXING SOME...BUT IT WONT TAKE MUCH TO TAP INTO THE HIGHER
MOMENTUM OFF THE SURFACE. 04Z HRRR SHOWS 40-50 KT GUSTS ACROSS
MOST OF THE AREA BY 19Z. LOOKS LIKE HIGHEST SPEEDS SHOULD DEVELOP
BY LATE MORNING OVER WEST CENTRAL IL AND THEN SPREAD QUICKLY
SOUTHEAST THROUGH MIDDAY AND EARLY AFTERNOON. WILL BE ISSUING WIND
ADVISORY FOR ENTIRE FORECAST AREA.
WINDS SHOULD DECREASE FROM NORTHWEST TO SOUTHEAST DURING THE
EVENING SHORTLY AFTER COLD FRONTAL PASSAGE. SPEAKING OF THE FRONT...
00Z MODEL SUITE IN GOOD AGREEMENT ON TIMING OF INCOMING COLD
FRONT AND POST-FRONTAL PRECIP. HOWEVER...MOST OF THE MODELS ARE
NOT HANDLING THE PRE-FRONTAL PRECIP CURRENTLY ALONG AND WEST OF
THE MISSISSIPPI IN THE WARM SECTOR. LATEST ECMWF(00Z) DOES HINT AT
AN AREA OF PRECIP OVER WEST CENTRAL IL AT 12Z. ORIGINALLY WAS
THINKING THAT ANY PRECIP CHANCE WOULD WAIT FOR THE FRONT...NOT
REACHING WESTERN FORECAST AREA UNTIL LATE MORNING...BUT WITH ONGOING
SHOWERS WILL INCLUDE A CHANCE OF RAIN FOR THE ENTIRE MORNING OVER
THE WEST.
LOOKS LIKE A ANAFRONT STRUCTURED FRONT AND THE BULK OF PRECIP SHOULD BE
MOSTLY ALONG AND BEHIND THE BOUNDARY. PRECIP WATER REMAINS WELL
ABOVE CLIMATOLOGY...99 PERCENTILE FOR NOVEMBER...AND ALTHOUGH THE
PERIOD OF RAIN AT ANY ONE SPOT SHOULDNT BE MORE THAN 12
HOURS...QPF SHOULD APPROACH AN INCH IN MOST AREAS WITH LOCALLY
HIGHER AMOUNTS. DESPITE MEAGER INSTABILITY...SHEAR IS IMPRESSIVE
AND MAY BE SUFFICIENT FOR ISOLATED EMBEDDED THUNDER BEHIND THE
FRONT WHICH COULD LOCALLY ENHANCE THE RAINFALL RATES.
STRONG COLD ADVECTION SURGES INTO THE AREA BEHIND THE FRONT AND
THERE MAY BE A BRIEF PERIOD OF A MIX OR A CHANGE TO SNOW BEFORE
THE PRECIP ENDS EARLY MONDAY. GROUND TEMPS SHOULD BE WARM ENOUGH
TO LIMIT ANY ACCUMULATION.
LONG TERM...MONDAY THROUGH SATURDAY
AFTER PRECIP MOVES OUT MONDAY MORNING...BIG STORY WILL BE THE
COLD ADVECTION. TEMPS WILL BE SUPPRESSED WITH HIGHS ON MONDAY
BEING SOME 20-25 DEGREES COOLER THAN SUNDAY IN MOST LOCATIONS AND
WITH BRISK WEST WINDS...WIND CHILLS WILL STAY OR FALL INTO THE 20S
AND 30S. CLEARING SHOULD SPREAD ACROSS THE AREA EARLY MONDAY. HIGH
PRESSURE CENTERS OVER ILLINOIS ON TUESDAY AND TUESDAY MORNING
SHOULD HAVE GOOD RADIATION AL COOLING CONDITIONS WITH A HARD FREEZE
LIKELY FOR MOST OF CENTRAL AND SOUTHEAST ILLINOIS.
850 MB TEMPS SLOWLY REBOUND AS THE AIR MASS MODERATES AFTER
TUESDAY AND TEMPS SHOULD REACH CLOSE TO NORMAL FOR THE LATER PART
OF THE WEEK.
MODEL SPREAD INCREASES SIGNIFICANTLY IN THE NAEFS AND OPERATIONAL
MODELS FOR THE LATER HALF OF THE WEEK WITH GENERALLY WEAK FLOW AND
ABOVE NORMAL HEIGHTS. MOST LIKELY SCENARIO SUGGESTS HIGH PRESSURE
RIDGING INTO IL FROM THE NORTHEAST KEEPING DRY WEATHER IN PLACE
INTO THE WEEKEND.
&&
.AVIATION...
ISSUED 515 AM CST SUN NOV 11 2012
MAIN CONCERNS THIS FORECAST PERIOD WILL BE WITH THE STRONG SOUTH
WINDS TODAY...TIMING OF FROPA THIS EVENING AND ASSOCIATED RAIN
CHANCES ALONG IT AND POTENTIAL FOR A PERIOD OF MVFR/IFR CIGS
TONIGHT AS MUCH COLDER AIR FILTERS INTO THE AREA. 12Z ILX SOUNDING
SHOWING 50-55 KTS AROUND THE 2000 FOOT LAYER...SO WILL CONTINUE
WITH THE LLWS FOR THE NEXT COUPLE OF HOURS.
COLD FRONT CURRENTLY JUST WEST OF DES MOINES AND SHOULD CROSS THE
MISSISSIPPI RIVER BY 21Z. WE HAVE HAD SOME ISOLD SHOWERS DEVELOP
IN A BROAD WARM ADVECTION PATTERN ACROSS THE MID-MISSISSIPPI VALLEY
OVERNIGHT...WEST OF THE TAF SITES. MOST OF THAT ACTIVITY SHOULD
REMAIN WEST OF OUR AREA UNTIL THE FRONT MAKES SOME EASTWARD PROGRESS
LATER TODAY. SOUTHERLY WINDS OF 20 TO 25 KTS...WITH OCCASIONAL GUSTS
UP TO 40 KTS WILL PREVAIL OVER THE FORECAST AREA TODAY BEFORE WINDS
SWITCH INTO THE WEST EARLY THIS EVENING AT PIA AND SPI...AND BY 03Z
OVER AT KCMI. WE SHOULD SEE CIGS GRADUALLY LOWER TODAY AND DROP TO
MVFR CATEGORY BY LATE AFTN OR EARLY EVENING ALONG AND JUST BEHIND
THE COLD FRONT. FORECAST SOUNDINGS SUGGEST ABOUT A 3-6 HOUR PERIOD
OF MVFR CIGS AND POSSIBLY LOWER IN SOME OF THE HEAVIER RAINS
TONIGHT. THE PRECIP SHOULD BE SHIFTING EAST OF THE TAF SITES BY
AROUND 09Z WITH CIGS AND VSBYS SLOWLY IMPROVING IN THE 09Z-12Z TIME
FRAME.
SMITH
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 10 AM THIS MORNING TO 8 PM CST THIS EVENING
FOR ILZ027>031-036>038-040>057-061>063-066>068-071>073.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
718 AM EST SUN NOV 11 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 533 AM EST SUN NOV 11 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP TROF OVER THE
ROCKIES UPSTREAM OF HI AMPLITUDE RDG IN THE E. VIGOROUS SHRTWV WITH
CLOSED LO AT H5 LIFTING NEWD THRU THE NRN PLAINS IS SUPPORTING 995MB
SFC LO PRES OVER NW MN AT 06Z. ATTENDANT SFC WARM FNT LIES W-E ACRS
NCNTRL WI...WITH SHARP TEMP GRADIENT ACRS THIS BNDRY. AT 05Z...SFC
TEMP WAS 51 AT WAUSAU WI TO 64 AT WISCONSIN RAPIDS LESS THAN 50
MILES TO THE S ACRS THE WARM FNT. THE H85 WARM FNT SEPARATING A 00Z
H85 TEMP OF 13C AT MPX FM 2C AT INL STRETCHES W-E ACRS LK SUP.
VIGOROUS WARM/MOIST ADVECTION WITH H7 WINDS AS HI AS 50-70KTS IN A
RIBBON JUST E OF THE ATTENDANT COLD FNT IN THE PLAINS HAS ADVECTED
PWAT OF NEARLY 1 INCH INTO THE UPR LKS...UP TO 250 PCT OF NORMAL.
NMRS SHRA WITH A FEW ELEVATED TS APPEAR TO BE TIED TO H85 WARM FNT
AND ENHANCED BY VIGOROUS UPR DVGC IN ADVANCE OF 130KT H3 JET MAX
LIFTING NEWD THRU THE PLAISN AND STEEPENING LAPSE RATES ACCOMPANYING
THE VIGOROUS WARM/MOIST ADVCTN AT H85-7. THE TS ARE MAINLY OVER WRN
LK SUP...AND THIS AREA OF PCPN IS LIFTING NEWD THRU LK SUP/THE ERN
CWA AT 06Z...BUT SCT -SHRA ARE ALSO PRESENT IN THE H85 WARM SECTOR S
THRU WI. THESE SHRA ARE TENDING TO DIMINISH WITH TIME. LOOKING TO
THE W...THE REMNANTS OF A LINE OF CONVECTION ARE PRESSING EWD THRU
MN AND INTO NW WI WELL AHEAD OF THE ASSOCIATED OCCLUDED/COLD FNT...
BUT LATEST RADAR TRENDS SHOW THIS BAND OF SHRA IS DIMINISHING. THE
THERMAL CONTRAST ACROSS THIS COLD FNT IS EQUALLY IMPRESSIVE... WITH
00Z H85 TEMPS RANGING FM 13C AT MPX AND OMAHA TO -11C AT BISMARCK.
ANOTHER VIGOROUS SHRTWV APPEARS TO BE ROUNDING THE BASE OF THE TROF
IN THE ROCKIES.
FCST CONCERNS DURING THE SHORT TERM ARE MANY AND INCLUDE SHRA/TS
CHCS THRU TNGT AS WELL AS TRANSITION TO MORE WINTRY WX TNGT AS COLD
FNT TO THE W PASSES THRU UPR MI.
TODAY...LATEST MODELS IN FAIRLY GOOD AGREEMENT SHOWING SFC LO IN MN
MOVING TO NEAR PICKLE LAKE ONTARIO BY 00Z MON WITH ATTENDANT COLD
FNT MOVING TO ABOUT MQT-IMT THEN. GUIDANCE REMAINS IN VERY GOOD
SHOWING H3 JET CORE UP TO 130KT LIFTING NNEWD TO NE MN/WRN LK SUP BY
00Z...WITH INCRSG PCPN COVERAGE MAINLY ALONG AND JUST BEHIND THE FNT
WITH ENHANCED UPR DVGC AND BAND OF SHARP FGEN THAT SHOWS UP BEST AT
H8-7 BEING THE MAIN FORCING MECHANISMS TO LIFT VERY MOIST AIRMASS.
GOING FCST POPS SHOWING INCRSG POPS TO CATEGORICAL OVER MUCH OF THE
W AND CENTRAL SEEM ON TRACK AND ARE IN NEED OF ONLY MINOR
ADJUSTMENTS. PCPN OVER THE MORE CAPPED E SHOULD REMAIN MAINLY SCT
-SHRA TO THE E OF THE INCOMING COLD FNT. EXPECT TEMPS TO RISE INTO
THE BALMY 50S FOLLOWING SFC WARM FROPA. ALTHOUGH THE PASSAGE OF THE
COLD FNT WL OPEN THE DOOR TO COLDER AIR TO MOVE INTO THE W HALF AND
FALLING TEMPS AFT WELL ABV NORMAL RELATIVELY EARLY HI TEMPS
ESPECIALLY OVER THE W...THE APRCH OF THE DISTURBANCE SUPPORTS MODEL
FCST THERMAL FIELDS THAT INDICATE THE PCPN WL REMAIN IN THE FORM OF
RA EVEN AT IWD UNTIL ALMOST 00Z.
TONIGHT...UPR DVGC IN RRQ OF 140KT H3 JET MAX/AXIS OF LO-MID LVL
FGEN ASSOCIATED WITH APRCHG SHRTWV WL BRING CATEGORICAL POPS TO
MAINLY THE E HALF OF THE CWA AS SFC FNT PUSHES SLOWLY TO THE
E...REACHING THE SAULT JUST A FEW HRS BEFORE 12Z MON. BULK OF MODELS
SHOW ENUF DRY MID LVL AIR PUSHING EWD TO LIMIT PCPN AMOUNTS OVER THE
W AND THEN CENTRAL WHERE THE AIR WL TURN COLD ENUF TO SUPPORT
SN...BUT H85 TEMPS FALLING TO -10C TO -14C BY 12Z MON OVER THE W WL
BE SUFFICIENTLY COLD TO BRING AT LEAST SCT LK EFFECT SHSN TO AREAS
FAVORED BY FCST W WIND DESPITE SLIGHTLY LLVL ACYC FLOW. ANY SN/SLEET
ACCUM SHOULD BE UNDER AN INCH. SHARP LLVL COOLING ASSOCIATED WITH
H85-7 FGEN MAX SLOPED FAIRLY FAR TO THE W OF THE SFC FNT MAY CREATE
ELEVATED WARM LYR/POTENTIAL FOR SLEET AS WELL AS SN TO THE CNTRL ZNS
ON THE WRN EDGE OF THE LARGER SYNOPTIC SCALE PCPN AREA TO THE E. THE
E SHOULD REMAIN WARM ENUF FOR MAINLY RA GIVEN FCST H85 TEMPS/H100-85
THKNS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 533 AM EST SUN NOV 11 2012
MAIN FOCUS INITIALLY IN LONG TERM IS DEEP/COLD/MOIST LOW-MID LEVEL
TROUGH EXTENDING FROM ONTARIO TO THE MIDDLE MISSISSIPPI RIVER
VALLEY ON MONDAY. SFC COLD FRONT WILL BE THROUGH UPR MICHIGAN BY 12Z
MONDAY. KEPT HIGHER POPS OVER FAR EAST FOR MAINLY SNOW THROUGH MID
MORNING...BUT WILL BE DRYING OUT ELSEWHERE OVER THE EAST IN WAKE OF
THE FRONT.
ALREADY PLENTY COLD ENOUGH AT H85 /H85 TEMPS AROUND -10C/ TO SUPPORT
LK EFFECT OFF LK SUPERIOR TO START THE DAY GIVEN WATER TEMPS AROUND
+8C. OVER-WATER INSTABILITY RAMPS UP FURTHER THROUGH THE DAY WITH
DELTA T/S WELL OVER 20C BY EVENING IN A MOIST ENVIRONMENT TO H7. NOT
THE USUALLY TYPICAL REALLY COLD BUT REALLY DRY AIRMASS FOR THE LK
EFFECT TO WORK ON...AT LEAST NOT UNTIL LATER MONDAY NIGHT WITH
ARRIVAL OF DRIER AIR AOA H85. NAM/GFS SOUNDINGS INDICATE INVERSION
HEIGHTS OR AT LEAST LAKE EQUILIBRIUM LEVELS TOPPING OUT AROUND 10KFT
AND LOW-LEVEL LAPSE RATES EXCEEDING 9C/KM. SINCE IT IS CHILLY AT SFC
AND ALOFT...MUCH OF THE LAKE CONVECTIVE LAYER WILL BE WITHIN HEART
OF DENDRITIC GROWTH ZONE...BOOSTING SLR/S AND ULTIMATELY SNOWFALL
TOTALS.
PRIMARY QUESTION IS HOW QUICKLY ON MONDAY WILL SIGNIFICANT LK EFFECT
SNOW SHOWERS DEVELOP AND WHERE WILL HEAVIER SNOWS OCCUR THROUGH
MONDAY NIGHT. LOW-LEVEL WINDS IN WAKE OF COLD FRONT ARE MORE FROM
WSW INITIALLY ON MONDAY MORNING WHICH FAVORS MAJORITY OF SNOW
IMPACTING MAINLY NORTHERN PORTIONS OF KEWEENAW PENINSULA. SFC WINDS
GRADUALLY TURN MORE NORTHWEST ON MONDAY EVENING AS SFC TROUGH WORKS
ACROSS LK SUPERIOR AND NORTHERN UPR MICHIGAN. SOUNDINGS INDICATE
THAT EVEN AS SUB H85 WINDS ARE MOSTLY FROM THE WSW MUCH OF MONDAY
THE WINDS FROM H8-H7 SHIFT TO NW DURING THE AFTN OVER WESTERN UPR
MICHIGAN. MAY SEE SITUATION WHERE MORE OF A WIDESPREAD SNOW ENVELOPS
MOST OF NW/W UPR MICHIGAN BY MID AFTN DUE TO COOL/MOIST PROFILE
UPWARDS OF H7. MEANWHILE...BLYR WINDS WOULD FAVOR CONVERGENCE BAND
OF HEAVIER SNOW TO SET UP SOMEWHERE ALONG WEST SIDE OF KEWEENAW THEN
GRADUALLY SINKING SOUTHWARD LATE IN THE DAY INTO THE EVENING WITH
THE SFC WIND SHIFT. ALL FACTORS ARE FAVORABLE FOR INTENSE SNOW RATES
AFTN-EVENING WHERE THE BAND DEVELOPS. INSTABILITY PARAMETERS AND
LOCAL GUIDANCE ALONG WITH LAKE SNOW PARAMETER DEVELOPED BY NWS
OFFICE IN GAYLORD MI ALL POINT TO HEAVY SNOWFALL RATES /AT LEAST 1"
PER HR/ LATER MONDAY AFTN AND MONDAY EVENING OVR NW UPR MICHIGAN.
CURRENTLY HAVE POTENTIAL FOR SNOW MENTIONED IN HAZARDOUS WEATHER
OUTLOOK FOR NW CWA. CANNOT FORGET THE FAR NORTHEAST CWA AS WELL WITH
WINDS SHIFTING ONSHORE AND LEADING TO POTENTIAL OF DOMINANT BAND OF
SNOW IMPACTING THOSE AREAS AS WELL...MAINLY EAST OF P53 INTO
NORTHERN LUCE COUNTY. AS MENTIONED IN PREVIOUS DISCUSSION...MORE
RESIDENCE TIME OVER THE WARMER LAKE WATERS AND A BIT MORE WARMER
AIRMASS OVERALL MAY ACT TO LIMIT SNOW AMOUNTS COMPARED TO WHAT IS
EXPECTED TO OCCUR OVER NW UPR MICHIGAN. SOME SNOW ACCUMULATIONS ARE
LIKELY THOUGH.
LATER MONDAY NIGHT AND FOR SURE INTO MID MORNING TUESDAY...WILL SEE
LK EFFECT DIMINISH SIGNIFICANTLY MAINLY DUE TO DEPARTURE OF MOISTURE
ABOVE H85 AND AS STEADILY WARMING TEMPS AT TOP OF 5KFT INVERSION.
MOISTURE DECREASES DRAMATICALLY BY 12Z TUESDAY...ESPECIALLY IN THE
WEST. COULD EVEN SEE SKIES BECOME MOSTLY CLEAR OVER FAR SOUTH AWAY
FROM EFFECTS OFF THE LAKE. IN ANY CASE...WHAT LAKE EFFECT IS LEFT
AT THAT TIME WILL BE SHADOW OF WHAT WILL HAVE JUST OCCURRED 12 HR
PREVIOUSLY. NO REAL CHANGES TO POPS FOR MONDAY THROUGH MONDAY NIGHT
AND INTO TUESDAY...JUST SOME TWEAKING TO MATCH LATEST MODEL TRENDS.
DID INCREASE SNOW AMOUNTS SOME OVER NORTHWEST GIVEN INCREASING
CONFIDENCE IN OVERALL SCENARIO. CURRENTLY FORECASTED SNOW AMOUNTS
SUPPORT ADVISORY HEADLINES EVENTUALLY. THAT SAID...CERTAINLY
POSSIBLE THAT AT LEAST ISOLD LOCATIONS FROM ONTONAGON THROUGH
HOUGHTON AND KEWEENAW COUTNIES MAY SEE WARNING CRITERIA SNOWFALL
FROM THIS EARLY SEASON LAKE SNOW EVENT. ON A SIDE NOTE...WINDS IN
THE STRONGER CONVERGENCE AREAS ACROSS KEWEENAW MAY TOP OUT 30-40 MPH
ON MONDAY AND MONDAY EVENING. SO IN ADDITION TO THE HEAVY SNOW COULD
ALSO SEE STRONG/GUSTY WINDS WITHIN THOSE HEAVIER SNOW SQUALLS.
PLAN TO MENTION THIS IN THE HAZARDOUS WEATHER OUTLOOK.
REST OF LONG TERM...PRETTY QUIET OVERALL AS PACIFIC FLOW ALOFT WILL
BE IN CONTROL. SFC HIGH BUILDS IN LATER TUESDAY AND MOVES EAST ON
WEDNESDAY. LOWERED MINS ON TUESDAY NIGHT WITH COLD AIRMASS IN PLACE.
MID CLOUDS INCREASE LATE BUT SEEMED REASONABLE TO START THE NIGHT
TEMPS COULD FALL OFF INTO THE TEENS BEFORE BECOMING MORE STEADY LATE.
WEDNESDAY MAY END UP FAIRLY CLOUDY...BUT REALLY WHAT ELSE IS NEW
LATELY. A LOT OF MID CLOUDS SHOW UP IN THE MODELS...BUT DRY SUB H85
AIR DUE TO LINGERING AFFECTS OF THE SFC HIGH AND NOT VERY STRONG
LIFT ALOFT RESULT IN KEEPING DRY FORECAST GOING FOR CWA. WEAK WARM
AIR ADVECTION AND ADDITIONAL MOISTURE ADVECTION AHEAD OF SFC TROUGH
MOVING ACROSS ONTARIO BY THURSDAY MORNING COULD PROVIDE CHANCE FOR
SOME LGT SNOW/FLURRIES ON WEDNESDAY NIGHT. DRY FORECAST TO CLOSE THE
WEEK AND THROUGH NEXT SATURDAY WITH LACK OF SYSTEMS MOVING THROUGH
IN THE WESTERLY FLOW. SW FLOW IN LOWER LEVELS FRIDAY/SATURDAY MAY
ALLOW FOR TEMPS TO PUSH SLIGHTY ABOVE NORMAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 716 AM EST SUN NOV 11 2012
EXPECT PREDOMINANT VFR CONDITIONS AND SOME LLWS AT ALL 3 SITES FOR A
TIME THIS MRNG WITH INFLUX OF RELATIVELY DRY/CAPPED AIRMASS IN THE
WAKE OF EARLIER WARM FROPA. AS A COLD FNT PRESSES E INTO UPR MI BY
THIS AFTN...EXPECT SHRA TO ARRIVE W-E WITH CONDITIONS DETERIORATING
TO MVFR THEN IFR AS A DISTURBANCE RIDING NEWD ALONG THE FNT CAUSES
AN EXPANSION OF RA AREA. LIFR CONDITIONS WL BE POSSIBLE FOR A TIME
AS WELL...ESPECIALLY AT CMX THIS AFTN/EVNG WITH GUSTY USPLOPE W WIND
BEHIND THE COLD FROPA. EXPECT THE ARRIVAL OF DRIER AIR TO CAUSE THE
PCPN TO DIMINISH JUST AS ENUF COLD AIR SURGES INTO THE AREA TO
CHANGE THE RA TO SN. THE BEST CHC FOR HEAVIER -SHSN/PERHAPS IFR WX
LATER TNGT WL BE AT THE MORE EXPOSED CMX LOCATION...WHERE GUSTY
WINDS WL LINGER AS WELL.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 533 AM EST SUN NOV 11 2012
EXPECT S WINDS UP TO 25 TO 30 KTS...STRONGEST OVER THE E HALF UNDER
TIGHTER PRES GRADIENT...IN ADVANCE OF AN APPROACHING COLD FRONT TO
SHIFT TO THE W FOLLOWING THE COLD FROPA OVER THE W THIS AFTERNOON AND
THEN OVER THE CENTRAL AND E TONIGHT AS MUCH COLDER AIR FLOWS OVER THE
RELATIVELY WARM LAKE WATERS AND ENHANCES MIXING OF STRONGER WINDS TO
THE SURFACE.
PRESSURE GRADIENT STAYS TIGHT ON MONDAY WITH WEST WINDS UP TO 30 KTS
AND OCCASIONAL GALE GUSTS TO 35 KTS. PRESSURE GRADIENT SLACKENS
MONDAY NIGHT AND TUESDAY WITH WINDS DIMINISHING BLO 25 KTS. A LOW
PRESSURE TROUGH WILL PUSH ACROSS NORTHERN ONTARIO ON THURSDAY. SOUTH
WINDS AHEAD OF THE TROUGH COULD REACH 25 KTS OVER EASTERN SECTIONS
OF LK SUPERIOR WEDNESDAY AND WEDNESDAY NIGHT. WINDS TO FINISH UP THE
WEEK WILL BE BLO 20 KTS AS PRESSURE GRADIENT DIMINISHES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...KC
MARINE...KC/JLA
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
627 AM EST SUN NOV 11 2012
.SYNOPSIS...
ISSUED AT 328 AM EST SUN NOV 11 2012
STRONG SOUTH WINDS WILL DEVELOP ACROSS THE REGION TODAY AHEAD OF A
STRONG COLD FRONT. A PUSH OF WARM AIR WILL SEND TEMPERATURES INTO
THE UPPER 60S A MANY LOCATIONS THIS AFTERNOON. SHOWERS WILL DEVELOP
LATE IN THE DAY AND CONTINUE TONIGHT AS THE FRONT MOVES ACROSS THE
AREA. MUCH COLDER AIR ALONG WITH RAIN AND SNOW SHOWERS WILL MOVE
INTO WEST MICHIGAN MONDAY. HIGH TEMPERATURES WILL SLOWLY FALL DURING
THE DAY AND ONLY REACH AROUND 40 DEGREES TUESDAY. MAINLY DRY WEATHER
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EST SUN NOV 11 2012
FORECAST CONCERNS DEAL WITH THE WIND POTENTIAL TODAY AND PCPN TRENDS
TONIGHT/MONDAY.
THE GOING FORECAST IS LARGELY ON TRACK. HOWEVER...WINDS APPEAR A BIT
STRONGER ACROSS THE WRN CWA AS THE GRADIENT TIGHTENS AHEAD OF THE
COLD FRONT. AS SUCH WE ISSUED A WIND ADVISORY FOR THE WRN 1/2 OF THE
CWA. WINDS ARE ALREADY GUSTING TO 36 KITS AT KMKG AND WILL LIKELY
INCREASE A BIT MORE AS THE SUN RISES AND BETTER MIXING OCCURS.
STRONG 65KT LLJ MOVES OVER THE WRN CWA LATE THIS AFTERNOON.
LATEST HRRR HAS A PRETTY GOOD HANDLE ON THE SHOWERS MOVING ACROSS
NRN IL/WISCONSIN. THESE ARE AHEAD OF THE COLD FRONT AND DISSIPATE
SOMEWHAT AS THEY MOVE EWD THIS AFTERNOON. AS A RESULT...WE
ANTICIPATE A DRY DAY. ABUNDANT MID CLOUD WILL BE PRESENT AND THIS
WILL LIMIT MIXING A BIT BUT NOT ENOUGH TO PREVENT SUSTAINED 25 TO 30
MPH WINDS. FROPA IS ON TRACK FOR MIDNIGHT-4AM TIME FRAME. TEMPS WILL
SLOWLY FALL MONDAY AS H8 TEMPS FALL TO -12C. RAIN WILL MIX WITH SNOW
AFTER FROPA THEN BECOME SHSN AS THE THERMAL PROFILE QUICKLY FALLS
BELOW 0C. NOT LOOKING FOR ACCUMS AT THIS POINT. THOUGH IT/S POSSIBLE
A FEW HIGHER ELEVATIONS ACROSS THE NRN CWA COULD SEE A COUPLE OF
TENTHS.
TUESDAY LOOKS DRY BUT CHILLY WITH HIGHS AROUND 40.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EST SUN NOV 11 2012
FOR THE EXTENDED PERIOD...THE CORE OF THE ARCTIC AIR REMAINS WELL
NORTH OF THE REGION. ONE OF THE MAIN REASONS FOR THIS IS THE ZONAL
MID LEVEL FLOW THAT SETS UP ACROSS NORTH AMERICA FOR THE PERIOD.
HERE IN MI...WE WILL SEE ONLY A WEAKENING COLD FRONT ARRIVING THU.
IF THERE IS ANY PRECIPITATION WITH THIS SHALLOW FEATURE...IT WILL BE
LIMITED AS VERY LITTLE MOISTURE AND LIFT WILL BE IN PLACE.
TEMPERATURES AT 850 MB CLIMB THU INTO SAT...SO WE WILL LIKELY SEE A
GENERAL WARMING TREND. ALTHOUGH...GIVEN THE MID LEVEL
FLOW...PACIFIC MOISTURE COULD CAUSE PERIODS OF CLOUDS THAT WOULD
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 620 AM EST SUN NOV 11 2012
SOUTH TO SOUTHWEST FLOW AHEAD OF THE COLD FRONT WILL INCREASE
TODAY AS WE HEAT UP. GUSTS OVER 25 KNOTS ARE EXPECTED FOR ALL TAF
SITES. LOCAL GUSTS OVER 35 KNOTS ARE POSSIBLE. WINDS SHIFT TO THE
WEST AS THE FRONT PASSES THOUGH LATE TONIGHT OR EARLY MON. THE
LACK OF LOW LEVEL MOISTURE WILL KEEP CONDITIONS VFR THROUGH SUNSET
LATER THIS AFTERNOON. HOWEVER WITH THE MOISTURE INCREASING
TONIGHT...THIS WILL CAUSE CONDITIONS TO LOWER TO MVFR WITH AN
INCREASED RISK OF IFR BEFORE DAYBREAK ON MONDAY.
&&
.MARINE...
ISSUED AT 328 AM EST SUN NOV 11 2012
GIVEN THAT WINDS ALONG THE LAKESHORE ARE ALREADY GUSTING NEAR
35KTS...DECIDED TO RUN WITH THE GALE WARNING NOW AND DISCONTINUE THE
SCA. GALES TO 40KTS EXPECTED TODAY WILL BUILD WAVES TO 5 TO 8 FEET.
&&
.HYDROLOGY...
ISSUED AT 328 AM EST SUN NOV 11 2012
A THIRD OF AN INCH OF PCPN IS EXPECTED AHEAD OF THE COLD FRONT
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WIND ADVISORY UNTIL 3 AM EST MONDAY FOR MIZ037-038-043-044-050-
056-057-064-065-071-072.
LM...GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LMZ844>849.
&&
$$
SYNOPSIS...93
SHORT TERM...93
LONG TERM...MJS
AVIATION...MJS
HYDROLOGY...93
MARINE...93
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
536 AM EST SUN NOV 11 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 533 AM EST SUN NOV 11 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP TROF OVER THE
ROCKIES UPSTREAM OF HI AMPLITUDE RDG IN THE E. VIGOROUS SHRTWV WITH
CLOSED LO AT H5 LIFTING NEWD THRU THE NRN PLAINS IS SUPPORTING 995MB
SFC LO PRES OVER NW MN AT 06Z. ATTENDANT SFC WARM FNT LIES W-E ACRS
NCNTRL WI...WITH SHARP TEMP GRADIENT ACRS THIS BNDRY. AT 05Z...SFC
TEMP WAS 51 AT WAUSAU WI TO 64 AT WISCONSIN RAPIDS LESS THAN 50
MILES TO THE S ACRS THE WARM FNT. THE H85 WARM FNT SEPARATING A 00Z
H85 TEMP OF 13C AT MPX FM 2C AT INL STRETCHES W-E ACRS LK SUP.
VIGOROUS WARM/MOIST ADVECTION WITH H7 WINDS AS HI AS 50-70KTS IN A
RIBBON JUST E OF THE ATTENDANT COLD FNT IN THE PLAINS HAS ADVECTED
PWAT OF NEARLY 1 INCH INTO THE UPR LKS...UP TO 250 PCT OF NORMAL.
NMRS SHRA WITH A FEW ELEVATED TS APPEAR TO BE TIED TO H85 WARM FNT
AND ENHANCED BY VIGOROUS UPR DVGC IN ADVANCE OF 130KT H3 JET MAX
LIFTING NEWD THRU THE PLAISN AND STEEPENING LAPSE RATES ACCOMPANYING
THE VIGOROUS WARM/MOIST ADVCTN AT H85-7. THE TS ARE MAINLY OVER WRN
LK SUP...AND THIS AREA OF PCPN IS LIFTING NEWD THRU LK SUP/THE ERN
CWA AT 06Z...BUT SCT -SHRA ARE ALSO PRESENT IN THE H85 WARM SECTOR S
THRU WI. THESE SHRA ARE TENDING TO DIMINISH WITH TIME. LOOKING TO
THE W...THE REMNANTS OF A LINE OF CONVECTION ARE PRESSING EWD THRU
MN AND INTO NW WI WELL AHEAD OF THE ASSOCIATED OCCLUDED/COLD FNT...
BUT LATEST RADAR TRENDS SHOW THIS BAND OF SHRA IS DIMINISHING. THE
THERMAL CONTRAST ACROSS THIS COLD FNT IS EQUALLY IMPRESSIVE... WITH
00Z H85 TEMPS RANGING FM 13C AT MPX AND OMAHA TO -11C AT BISMARCK.
ANOTHER VIGOROUS SHRTWV APPEARS TO BE ROUNDING THE BASE OF THE TROF
IN THE ROCKIES.
FCST CONCERNS DURING THE SHORT TERM ARE MANY AND INCLUDE SHRA/TS
CHCS THRU TNGT AS WELL AS TRANSITION TO MORE WINTRY WX TNGT AS COLD
FNT TO THE W PASSES THRU UPR MI.
TODAY...LATEST MODELS IN FAIRLY GOOD AGREEMENT SHOWING SFC LO IN MN
MOVING TO NEAR PICKLE LAKE ONTARIO BY 00Z MON WITH ATTENDANT COLD
FNT MOVING TO ABOUT MQT-IMT THEN. GUIDANCE REMAINS IN VERY GOOD
SHOWING H3 JET CORE UP TO 130KT LIFTING NNEWD TO NE MN/WRN LK SUP BY
00Z...WITH INCRSG PCPN COVERAGE MAINLY ALONG AND JUST BEHIND THE FNT
WITH ENHANCED UPR DVGC AND BAND OF SHARP FGEN THAT SHOWS UP BEST AT
H8-7 BEING THE MAIN FORCING MECHANISMS TO LIFT VERY MOIST AIRMASS.
GOING FCST POPS SHOWING INCRSG POPS TO CATEGORICAL OVER MUCH OF THE
W AND CENTRAL SEEM ON TRACK AND ARE IN NEED OF ONLY MINOR
ADJUSTMENTS. PCPN OVER THE MORE CAPPED E SHOULD REMAIN MAINLY SCT
-SHRA TO THE E OF THE INCOMING COLD FNT. EXPECT TEMPS TO RISE INTO
THE BALMY 50S FOLLOWING SFC WARM FROPA. ALTHOUGH THE PASSAGE OF THE
COLD FNT WL OPEN THE DOOR TO COLDER AIR TO MOVE INTO THE W HALF AND
FALLING TEMPS AFT WELL ABV NORMAL RELATIVELY EARLY HI TEMPS
ESPECIALLY OVER THE W...THE APRCH OF THE DISTURBANCE SUPPORTS MODEL
FCST THERMAL FIELDS THAT INDICATE THE PCPN WL REMAIN IN THE FORM OF
RA EVEN AT IWD UNTIL ALMOST 00Z.
TONIGHT...UPR DVGC IN RRQ OF 140KT H3 JET MAX/AXIS OF LO-MID LVL
FGEN ASSOCIATED WITH APRCHG SHRTWV WL BRING CATEGORICAL POPS TO
MAINLY THE E HALF OF THE CWA AS SFC FNT PUSHES SLOWLY TO THE
E...REACHING THE SAULT JUST A FEW HRS BEFORE 12Z MON. BULK OF MODELS
SHOW ENUF DRY MID LVL AIR PUSHING EWD TO LIMIT PCPN AMOUNTS OVER THE
W AND THEN CENTRAL WHERE THE AIR WL TURN COLD ENUF TO SUPPORT
SN...BUT H85 TEMPS FALLING TO -10C TO -14C BY 12Z MON OVER THE W WL
BE SUFFICIENTLY COLD TO BRING AT LEAST SCT LK EFFECT SHSN TO AREAS
FAVORED BY FCST W WIND DESPITE SLIGHTLY LLVL ACYC FLOW. ANY SN/SLEET
ACCUM SHOULD BE UNDER AN INCH. SHARP LLVL COOLING ASSOCIATED WITH
H85-7 FGEN MAX SLOPED FAIRLY FAR TO THE W OF THE SFC FNT MAY CREATE
ELEVATED WARM LYR/POTENTIAL FOR SLEET AS WELL AS SN TO THE CNTRL ZNS
ON THE WRN EDGE OF THE LARGER SYNOPTIC SCALE PCPN AREA TO THE E. THE
E SHOULD REMAIN WARM ENUF FOR MAINLY RA GIVEN FCST H85 TEMPS/H100-85
THKNS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 533 AM EST SUN NOV 11 2012
MAIN FOCUS INITIALLY IN LONG TERM IS DEEP/COLD/MOIST LOW-MID LEVEL
TROUGH EXTENDING FROM ONTARIO TO THE MIDDLE MISSISSIPPI RIVER
VALLEY ON MONDAY. SFC COLD FRONT WILL BE THROUGH UPR MICHIGAN BY 12Z
MONDAY. KEPT HIGHER POPS OVER FAR EAST FOR MAINLY SNOW THROUGH MID
MORNING...BUT WILL BE DRYING OUT ELSEWHERE OVER THE EAST IN WAKE OF
THE FRONT.
ALREADY PLENTY COLD ENOUGH AT H85 /H85 TEMPS AROUND -10C/ TO SUPPORT
LK EFFECT OFF LK SUPERIOR TO START THE DAY GIVEN WATER TEMPS AROUND
+8C. OVER-WATER INSTABILITY RAMPS UP FURTHER THROUGH THE DAY WITH
DELTA T/S WELL OVER 20C BY EVENING IN A MOIST ENVIRONMENT TO H7. NOT
THE USUALLY TYPICAL REALLY COLD BUT REALLY DRY AIRMASS FOR THE LK
EFFECT TO WORK ON...AT LEAST NOT UNTIL LATER MONDAY NIGHT WITH
ARRIVAL OF DRIER AIR AOA H85. NAM/GFS SOUNDINGS INDICATE INVERSION
HEIGHTS OR AT LEAST LAKE EQUILIBRIUM LEVELS TOPPING OUT AROUND 10KFT
AND LOW-LEVEL LAPSE RATES EXCEEDING 9C/KM. SINCE IT IS CHILLY AT SFC
AND ALOFT...MUCH OF THE LAKE CONVECTIVE LAYER WILL BE WITHIN HEART
OF DENDRITIC GROWTH ZONE...BOOSTING SLR/S AND ULTIMATELY SNOWFALL
TOTALS.
PRIMARY QUESTION IS HOW QUICKLY ON MONDAY WILL SIGNIFICANT LK EFFECT
SNOW SHOWERS DEVELOP AND WHERE WILL HEAVIER SNOWS OCCUR THROUGH
MONDAY NIGHT. LOW-LEVEL WINDS IN WAKE OF COLD FRONT ARE MORE FROM
WSW INITIALLY ON MONDAY MORNING WHICH FAVORS MAJORITY OF SNOW
IMPACTING MAINLY NORTHERN PORTIONS OF KEWEENAW PENINSULA. SFC WINDS
GRADUALLY TURN MORE NORTHWEST ON MONDAY EVENING AS SFC TROUGH WORKS
ACROSS LK SUPERIOR AND NORTHERN UPR MICHIGAN. SOUNDINGS INDICATE
THAT EVEN AS SUB H85 WINDS ARE MOSTLY FROM THE WSW MUCH OF MONDAY
THE WINDS FROM H8-H7 SHIFT TO NW DURING THE AFTN OVER WESTERN UPR
MICHIGAN. MAY SEE SITUATION WHERE MORE OF A WIDESPREAD SNOW ENVELOPS
MOST OF NW/W UPR MICHIGAN BY MID AFTN DUE TO COOL/MOIST PROFILE
UPWARDS OF H7. MEANWHILE...BLYR WINDS WOULD FAVOR CONVERGENCE BAND
OF HEAVIER SNOW TO SET UP SOMEWHERE ALONG WEST SIDE OF KEWEENAW THEN
GRADUALLY SINKING SOUTHWARD LATE IN THE DAY INTO THE EVENING WITH
THE SFC WIND SHIFT. ALL FACTORS ARE FAVORABLE FOR INTENSE SNOW RATES
AFTN-EVENING WHERE THE BAND DEVELOPS. INSTABILITY PARAMETERS AND
LOCAL GUIDANCE ALONG WITH LAKE SNOW PARAMETER DEVELOPED BY NWS
OFFICE IN GAYLORD MI ALL POINT TO HEAVY SNOWFALL RATES /AT LEAST 1"
PER HR/ LATER MONDAY AFTN AND MONDAY EVENING OVR NW UPR MICHIGAN.
CURRENTLY HAVE POTENTIAL FOR SNOW MENTIONED IN HAZARDOUS WEATHER
OUTLOOK FOR NW CWA. CANNOT FORGET THE FAR NORTHEAST CWA AS WELL WITH
WINDS SHIFTING ONSHORE AND LEADING TO POTENTIAL OF DOMINANT BAND OF
SNOW IMPACTING THOSE AREAS AS WELL...MAINLY EAST OF P53 INTO
NORTHERN LUCE COUNTY. AS MENTIONED IN PREVIOUS DISCUSSION...MORE
RESIDENCE TIME OVER THE WARMER LAKE WATERS AND A BIT MORE WARMER
AIRMASS OVERALL MAY ACT TO LIMIT SNOW AMOUNTS COMPARED TO WHAT IS
EXPECTED TO OCCUR OVER NW UPR MICHIGAN. SOME SNOW ACCUMULATIONS ARE
LIKELY THOUGH.
LATER MONDAY NIGHT AND FOR SURE INTO MID MORNING TUESDAY...WILL SEE
LK EFFECT DIMINISH SIGNIFICANTLY MAINLY DUE TO DEPARTURE OF MOISTURE
ABOVE H85 AND AS STEADILY WARMING TEMPS AT TOP OF 5KFT INVERSION.
MOISTURE DECREASES DRAMATICALLY BY 12Z TUESDAY...ESPECIALLY IN THE
WEST. COULD EVEN SEE SKIES BECOME MOSTLY CLEAR OVER FAR SOUTH AWAY
FROM EFFECTS OFF THE LAKE. IN ANY CASE...WHAT LAKE EFFECT IS LEFT
AT THAT TIME WILL BE SHADOW OF WHAT WILL HAVE JUST OCCURRED 12 HR
PREVIOUSLY. NO REAL CHANGES TO POPS FOR MONDAY THROUGH MONDAY NIGHT
AND INTO TUESDAY...JUST SOME TWEAKING TO MATCH LATEST MODEL TRENDS.
DID INCREASE SNOW AMOUNTS SOME OVER NORTHWEST GIVEN INCREASING
CONFIDENCE IN OVERALL SCENARIO. CURRENTLY FORECASTED SNOW AMOUNTS
SUPPORT ADVISORY HEADLINES EVENTUALLY. THAT SAID...CERTAINLY
POSSIBLE THAT AT LEAST ISOLD LOCATIONS FROM ONTONAGON THROUGH
HOUGHTON AND KEWEENAW COUTNIES MAY SEE WARNING CRITERIA SNOWFALL
FROM THIS EARLY SEASON LAKE SNOW EVENT. ON A SIDE NOTE...WINDS IN
THE STRONGER CONVERGENCE AREAS ACROSS KEWEENAW MAY TOP OUT 30-40 MPH
ON MONDAY AND MONDAY EVENING. SO IN ADDITION TO THE HEAVY SNOW COULD
ALSO SEE STRONG/GUSTY WINDS WITHIN THOSE HEAVIER SNOW SQUALLS.
PLAN TO MENTION THIS IN THE HAZARDOUS WEATHER OUTLOOK.
REST OF LONG TERM...PRETTY QUIET OVERALL AS PACIFIC FLOW ALOFT WILL
BE IN CONTROL. SFC HIGH BUILDS IN LATER TUESDAY AND MOVES EAST ON
WEDNESDAY. LOWERED MINS ON TUESDAY NIGHT WITH COLD AIRMASS IN PLACE.
MID CLOUDS INCREASE LATE BUT SEEMED REASONABLE TO START THE NIGHT
TEMPS COULD FALL OFF INTO THE TEENS BEFORE BECOMING MORE STEADY LATE.
WEDNESDAY MAY END UP FAIRLY CLOUDY...BUT REALLY WHAT ELSE IS NEW
LATELY. A LOT OF MID CLOUDS SHOW UP IN THE MODELS...BUT DRY SUB H85
AIR DUE TO LINGERING AFFECTS OF THE SFC HIGH AND NOT VERY STRONG
LIFT ALOFT RESULT IN KEEPING DRY FORECAST GOING FOR CWA. WEAK WARM
AIR ADVECTION AND ADDITIONAL MOISTURE ADVECTION AHEAD OF SFC TROUGH
MOVING ACROSS ONTARIO BY THURSDAY MORNING COULD PROVIDE CHANCE FOR
SOME LGT SNOW/FLURRIES ON WEDNESDAY NIGHT. DRY FORECAST TO CLOSE THE
WEEK AND THROUGH NEXT SATURDAY WITH LACK OF SYSTEMS MOVING THROUGH
IN THE WESTERLY FLOW. SW FLOW IN LOWER LEVELS FRIDAY/SATURDAY MAY
ALLOW FOR TEMPS TO PUSH SLIGHTY ABOVE NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1224 AM EST SUN NOV 11 2012
SHOWERS LIFTING OVER THE AREA WITH PASSAGE OF WARM FRONT COMBINED
WITH MOIST UPSLOPE E-SE FLOW SHOULD MAINTAIN CONDITIONS AT AIRFIELD
LANDING MINS AT KCMX AND ALT LANDING MINS AT KSAW THROUGH AT LEAST
08Z. AT KIWD...LOW STRATUS HAS LIFTED OUT TEMPORARILY BUT SCT SHRA
AND ISOLD TSRA COULD AFFECT AIRPORT INTO THE OVERNIGHT. AS WINDS
SHIFT SRLY LATE TONIGHT...LOOK FOR CONDITIONS TO IMPROVE TO LOW MVFR
AT KSAW AND KCMX. AS THE COLD FRONT ADVANCES FROM THE PLAINS...SHRA
WILL ARRIVE AT KIWD AND KCMX BY LATE SUNDAY MORNING AND AT KSAW BY
MID-LATE AFTERNOON SENDING CONDITIONS BACK DOWN TO IFR. SOME MID-LVL
INSTABILITY WILL ALSO WARRANT A MENTION OF VCTS AT ALL SITES AHEAD
OF THE COLD FRONT ARRIVAL. WINDS SHIFTING TO AN ONSHORE/UPSLOPE WRLY
DIRECTION BEHIND THE FRONT MAY ALSO LOWER VSBYS/CIGS DOWN NEAR ALT
LANDING MINS AT KIWD AND KCMX SUN AFTERNOON. COLD ADVECTION WILL
CHANGE PCPN OVER TO SNOW BY EARLY EVENING AT KIWD AND BY LATE
EVENING AT KCMX.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 533 AM EST SUN NOV 11 2012
EXPECT S WINDS UP TO 25 TO 30 KTS...STRONGEST OVER THE E HALF UNDER
TIGHTER PRES GRADIENT...IN ADVANCE OF AN APPROACHING COLD FRONT TO
SHIFT TO THE W FOLLOWING THE COLD FROPA OVER THE W THIS AFTERNOON AND
THEN OVER THE CENTRAL AND E TONIGHT AS MUCH COLDER AIR FLOWS OVER THE
RELATIVELY WARM LAKE WATERS AND ENHANCES MIXING OF STRONGER WINDS TO
THE SURFACE.
PRESSURE GRADIENT STAYS TIGHT ON MONDAY WITH WEST WINDS UP TO 30 KTS
AND OCCASIONAL GALE GUSTS TO 35 KTS. PRESSURE GRADIENT SLACKENS
MONDAY NIGHT AND TUESDAY WITH WINDS DIMINISHING BLO 25 KTS. A LOW
PRESSURE TROUGH WILL PUSH ACROSS NORTHERN ONTARIO ON THURSDAY. SOUTH
WINDS AHEAD OF THE TROUGH COULD REACH 25 KTS OVER EASTERN SECTIONS
OF LK SUPERIOR WEDNESDAY AND WEDNESDAY NIGHT. WINDS TO FINISH UP THE
WEEK WILL BE BLO 20 KTS AS PRESSURE GRADIENT DIMINISHES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...VOSS
MARINE...KC/JLA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
608 AM EST SUN NOV 11 2012
.SYNOPSIS...
LOW PRESSURE OVER MINNESOTA WILL CONTINUE NORTH INTO CANADA TODAY.
A STRONG COLD FRONT ASSOCIATED WITH THIS LOW WILL SWEEP EAST
ACROSS THE LOCAL AREA ON MONDAY. HIGH PRESSURE WILL THEN BUILD
OVER THE REGION FOR THE REMAINDER OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MADE SOME MINOR ADJUSTMENTS TO THE CLOUD COVER OTHERWISE NO
CHANGES.
PREVIOUS...SOUTHERLY WINDS HAVE STAYED UP OVERNIGHT AND THIS HAS
KEPT TEMPS IN THE MIDDLE 50S MOST AREAS. THE AREA IS NOW
COMFORTABLY IN THE WARM SECTOR AND SEE NO REASON WHY TEMPS WON`T
BE A FEW DEGREES WARMER THAN THEY WERE ON SATURDAY. SOME HIGH
CLOUDS WILL OVERSPREAD THE AREA TODAY BUT THESE SHOULD BE FAIRLY
THIN. HAVE GONE A COUPLE DEGREES ABOVE GUIDANCE AND MUCH OF THE
AREA WILL HAVE A SHOT AT REACHING 70 DEGREES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
NOT MUCH CHANGE TO THE SHORT TERM PERIOD THIS MORNING. MODELS NOW
IN GOOD AGREEMENT BRINGING A STRONG COLD FRONT ACROSS THE AREA ON
MONDAY. THIS FRONT SHOULD REACH THE WESTERN TIP OF THE AREA AROUND
DAYBREAK AND MOVE INTO NW PA BY EARLY AFTERNOON. WILL SEE A LINE
OF SHOWERS ALONG AND BEHIND THIS FRONT AND THE ENTIRE AREA WILL
SEE A SEVERAL HOUR PERIOD OF PRECIPITATION. GIVEN THE TIME OF
DAY...NOT EXPECTING MUCH IF ANY THUNDER WITH THE SHOWERS.
DEWPOINTS COULD POOL INTO THE 50S IN NW PA AND FAR NE OH BEFORE
THE FRONT ARRIVES AND IF ANY AREA HAS A SHOT FOR THUNDER IT COULD
BE THERE. EXPECT CLOSE TO A HALF INCH OF PRECIP MOST AREAS. NEXT
QUESTION IS HOW QUICK THE PRECIP WILL END. IT NOW APPEARS THAT NW
OH AND PORTIONS OF N-CENTRAL OH WILL BE DRY BY LATE TOMORROW
AFTERNOON. HAVE FINE TUNED PRECIP CHANCES. REALISTICALLY...ONLY
ABOUT THE EAST THIRD OF THE AREA HAS A SHOT OF MEASURABLE PRECIP
AFTER 00Z TUE. BY THAT TIME LOW LEVEL THICKNESSES COULD GET COLD
ENOUGH FOR SNOW SHOWERS OR MIXED PRECIP TO THE EAST OF KCLE. ANY
PRECIP THAT FALLS AFTER DARK SHOULD BE FAIRLY LIGHT AND NOT
EXPECTING ANY ACCUMS. BY DAYBREAK TUESDAY 850 MB TEMPS WILL BE
AROUND NEG 8 SO LAKE EFFECT CLOUDS ARE LIKELY IN THE WESTERLY
FLOW. COULD ALSO SEE A FEW SHOWERS EVEN THOUGH THE LOWER
ATMOSPHERE WILL BE FAIRLY DRY. RIDGING WILL MOVE INTO THE AREA
LATER TUESDAY AND THIS SHOULD END THE PRECIP THREAT. TEMPS COULD
SNEAK INTO THE 60S OVER EASTERN AREAS MONDAY AHEAD OF THE FRONT.
THE REST OF THE PERIOD WILL SEE BELOW NORMAL TEMPS. HAVE STAYED
PRETTY CLOSE TO GUIDANCE MOST PERIODS.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
MODELS CONTINUE TO BE IN REASONABLE AGREEMENT IN THE LONG TERM WITH
HIGH PRESSURE ANCHORED OVER THE GREAT LAKES. MODELS MOVE LOW
PRESSURE SYSTEM ACROSS THE LOWER TENNESSEE VALLEY LATE IN THE WEEK
AND THEN UP THE EAST COAST THIS WEEKEND. ALTHOUGH EXACT TRACK AND
TIMING OF LOW OFF SOMEWHAT BOTH MODELS HAVE THE LOW OFF THE VIRGINIA
COAST BY SUNDAY AFTERNOON. AT THIS POINT HIGH SEEMS STRONG ENOUGH
THAT WILL KEEP FORECAST DRY THROUGH THE ENTIRE FORECAST PERIOD.
TEMPS CONTINUE TO SHOW A VERY GRADUAL WARMING TREND.
&&
.AVIATION /11Z SUNDAY THROUGH THURSDAY/...
LOOKING AT WINDS AND TEMPS...BEST FIT FOR WARM FRONT PLACEMENT
TAKES IT FROM CENTRAL LWR MI ESE ACROSS LAKE ERIE INTO NERN OHIO.
WINDS AT KERI ARE FRONT 060 DEGREES AND KCLE AND KYNG HAVE BACKED
10 TO 30 DEGREES OVER THE PAST COUPLE HOURS SO FRONT MAY BE
WAFFLING A BIT INTO THE AREA. A QUICK LOOK AT THE HRRR HIGH REZ
WIND FORECAST SUGGESTS THIS STOPS AND REVERSES OVER THE NEXT
COUPLE HOURS TURNING WINDS AT KERI BACK TO SOUTHERLY. HAVE ALSO
SEEN DEVELOPMENT OF A CIG AROUND 45 HUNDRED FEET AT KERI AND
SATELLITE SHOWS A SIMILAR DECK DEVELOPING IN VICINITY OF KCLE AS
WELL. WILL CARRY THIS FOR THE NEXT FEW HOURS BUT WITH THE WARM
FRONT BEGINNING TO MOVE NORTH AGAIN WILL NOT CARRY THROUGH THE
NIGHT. OTHER THAN THAT EXPECT ONLY CONVECTIVE DEBRIS CLOUDS
100-120 FEET TO AFFECT TERMINALS OVERNIGHT. SUNDAY...THROUGH THE
DAY EXPECT VFR CONDITIONS BUT WINDS WILL INCREASE TO AROUND 15
KNOTS GUSTING INTO THE MID 20 KNOT RANGE KCLE AND POINTS WEST.
FURTHER EAST GUSTS TO NEAR 20.
OUTLOOK...NON-VFR DEVELOPING IN SHOWERS MONDAY THROUGH MONDAY
EVENING ALONG WITH GUSTY WINDS...LINGERING NON VFR NE OH/NW PA ON
TUESDAY.
&&
.MARINE...
SOUTH FLOW WILL BECOME BREEZY THIS AFTERNOON...BUT AS COLD AS THE
LAKE IS DO NOT THINK A LOT OF THE WIND WILL MIX DOWN TO THE LAKE
ITSELF. THEREFORE WILL NOT GO WITH A SMALL CRAFT ADVISORY TODAY. A
SMALL CRAFT WILL LIKELY BE NEEDED TONIGHT. MODELS CONTINUE TO BE IN
GOOD AGREEMENT ON THE TIMING OF THE STRONG COLD FRONT MONDAY. WINDS
TURN TO THE WEST AND INCREASE TO 30 KNOTS MONDAY AS THE FRONT MOVES
ACROSS THE LAKE. THE 850MB TEMPS DIP TO MINUS 10C BY TUESDAY.
SMALL CRAFT LIKELY UNTIL LATE TUESDAY AS HIGH PRESSURE MOVES OVER
THE LAKE. AFTER THAT HIGH PRESSURE WILL BE DOMINATE FEATURE INTO
NEXT WEEKEND.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KUBINA
NEAR TERM...KUBINA
SHORT TERM...KUBINA
LONG TERM...DJB
AVIATION...DJB
MARINE...DJB
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
518 AM CST SUN NOV 11 2012
.DISCUSSION.../ISSUED AT 331 AM CST/
MAJOR TROUGH MOVING THROUGH THIS MORNING WITH SUBSIDENCE BECOMING
STRONGER THROUGH THE DAY. OUTSIDE OF A FEW FLURRIES NOT REALLY
EXPECTING MUCH IN THE WAY OF PRECIPITATION. VERY COLD AIR POURING
INTO THE REGION WITH WIND CHILL VALUES INT HE SINGLE DIGITS WEST OF
INTERSTATE 29. VERY LITTLE REBOUND TODAY WITH CONTINUED COLD AIR
ADVECTION AND SOME CLOUD COVER TO SHAKE OFF SO ONLY EXPECTING A
REBOUND OF 5 TO 8 DEGREES FROM THIS MORNINGS LOW TEMPERATURE.
SO...LOWERED HIGHS A COUPLE OF DEGREES...ESPECIALLY WEST WHERE A
LITTLE ACCUMULATING SNOW MAY HAVE FALLEN.
JUST AS THE CLOUDS SCOUR OUT FROM SOUTH TO NORTH TODAY ADDITIONAL
CLOUD COVER WILL BUILD SOUTH FROM NORTH DAKOTA AS THE COLD CORE LOW
BUILDS SOUTHWARD. WILL CONTINUE A SMALL CHANCE FOR SNOWFALL NORTH OF
INTERSTATE 90 AS THIS DOES SO WITH MODERATELY STEEP LAPSE RATES
DEVELOPING. IF THIS COLD CORE WAS MOVING THROUGH DURING THE DAY
CONFIDENCE IN A FEW SNOW SHOWERS WOULD BE A LITTLE HIGHER. NOT
AIMING TOO LOW WITH CLOUD COVER BUT STILL BELIEVE TEENS TO LOWER 20S
WILL BE COMMON.
BY MONDAY A GOOD MIXING WESTERLY WIND AND DECREASING CLOUD COVER
WILL ALLOW FOR SOME WARMING...AND INCREASED HIGHS JUST A BIT TO
ACCOUNT FOR POTENTIALLY DECENT MIXING CONDITIONS...BUT STILL ONLY IN
THE 30S.
WINDS WILL TURN TO THE SOUTH MONDAY NIGHT INTO TUESDAY ALLOWING FOR
LESS COLD CONDITIONS. LOWS STILL IN THE TEENS TO MID 20S WITH HIGHS
CLIMBING BACK INTO THE 40S. IF THE NAM LOW LEVEL THERMAL FIELD IS A
LITTLE CLOSER AREAS IN THE SOUTHERN CWA COULD CLIMB INTO THE LOWER
50S.
IN THE LATTER PERIODS(WED/SAT)...OVERALL LOOKS FAIRLY QUIET THROUGH
THE PERIOD WITH SPLIT FLOW DEVELOPING EARLY AND SOME HINT OF A WEAK
SOUTHERN STREAM WAVE MOVING IN ON SATURDAY. GENERALLY SPLIT FLOW IS
FAIRLY QUIET SO WILL CONTINUE WITH NO REAL THREAT FOR
PRECIPITATION...EXCEPT CONTINUE THE POP FOR SATURDAYS WEAK WAVE.
OTHERWISE...TEMPERATURES FAIRLY SEASONAL THROUGH THE PERIOD WITH NO
MAJOR COOL DOWNS OR WARM UPS...SO WILL BE SHOOTING FOR HIGHS MAINLY
IN THE 40S TO LOWER 50S AND LOWS IN THE 20S TO LOWER 30S WITH THE
POTENTIAL FOR SOME WARMER LOWS ON SATURDAY MORNING AHEAD OF THE
INCOMING WAVE. /08
&&
.AVIATION.../FOR THE 12Z TAF ISSUANCE/
NAM AND RUC SHOW A STOUT INVERSION AROUND 900MB UNTIL AROUND 9-10 AM
LOCAL TIME AT FSD AND SUX WITH DRYING BELOW THE INVERSION. HON
SOUNDINGS SHOW THE INVERSION LIFTING AROUND 7-8AM LOCAL. WILL START
RAISING CIGS AROUND THE AFOREMENTIONED TIMES. SOME BREAKS IN THE
CLOUDS WILL BE POSSIBLE LATER THIS MORNING BUT ANOTHER SLUG OF
MOISTURE RETURNS AS WELL AS AN UPPER LEVEL TROF AND CLOUDS WILL FILL
BACK IN IN THE AFTERNOON THROUGH THE EVENING WITH VFR EXPECTED.
GUSTY WIND WILL CONTINUE THROUGH THE DAY AND INTO THE EARLY EVENING
WITH GUSTS STARTING TO SUBSIDE A FEW HOURS AFTER SUNSET.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
607 AM CST SUN NOV 11 2012
.SHORT TERM...TODAY
607 AM CST SUN NOV 11 2012
BASED ON THE LAST FEW RUNS OF RAP SOUNDINGS ACROSS THE
REGION...HAVE DECIDED TO PULL THE FREEZING RAIN FROM THE FORECAST
FOR TODAY SINCE IT APPEARS THAT SURFACE TEMPERATURES WILL HAVE A
HARD TIME TO DROP BELOW FREEZING BEFORE THE WARM LAYER COOLS. THIS
MEANS THAT THE RAIN WILL CHANGE OVER TO A PERIOD OF SLEET/SNOW
PELLETS BEFORE CHANGING OVER TO ALL SNOW THIS AFTERNOON/EVENING.
WILL HAVE TO MONITOR THE BACK SIDE OF THE PRECIPITATION SHIELD IN
CASE ICE CREATION IS LOST IN THE -10C TO -20C DENDRITIC GROWTH
ZONE AND SOME DRIZZLE FALLS IN SUB FREEZING AIR.
.LONG TERM...WEDNESDAY THROUGH SATURDAY
313 AM CST SUN NOV 11 2012
HIGH PRESSURE SETS UP ACROSS THE EASTERN HALF OF THE US ON
WEDNESDAY AND LINGERS THROUGH NEXT WEEKEND AND SHOULD LEAVE DRY
CONDITIONS THROUGH THE PERIOD. WITH THE UPPER MISSISSIPPI RIVER
VALLEY BEING ON THE WESTERN PERIPHERY OF THE RIDGE THERE SHOULD BE
SOUTHERLY SURFACE TO LOW LEVEL WINDS THAT WILL KEEP TEMPERATURES
AT ABOUT NORMAL.
&&
.AVIATION...TODAY AND TONIGHT
557 AM CST SUN NOV 11 2012
A STRONG COLD FRONT WILL PUSH ACROSS THE AREA TODAY BRINGING RAIN
TO THE TAF SITES THIS MORNING...SWITCHING OVER TO A MIX OF SLEET
AND SNOW THIS AFTERNOON WITH A SWITCH OVER TO ALL SNOW LATE IN THE
AFTERNOON INTO THE EARLY EVENING HOURS. PLAN ON IFR CONDITIONS
EARLY THIS MORNING AT KRST WITH CLOUD BASES AT 500 FT ALONG WITH LIGHT
RAIN AND BR. IFR CONDITIONS WILL DEVELOP AT KLSE AROUND 14Z AS
RAIN AND LOW CLOUDS MOVE IN WITH CLOUD BASES LOWERING TO AROUND
900 FT. WINDS WILL SWITCH TO THE WEST THEN NORTHWEST AS THE FRONT
MOVES IN. LOOK FOR THE RAIN TO SWITCH OVER TO A MIX OF SLEET AND
SNOW AROUND 19Z AT KRST AND AROUND 22Z AT KLSE. THE PRECIPITATION
SHOULD SWITCH OVER TO ALL SNOW AT KRST BY 21Z WITH IFR CONDITIONS
PERSISTING...WITH CEILINGS AROUND 600 FT AND VISIBILITIES REDUCED
TO AROUND 3SM IN SNOW. THE PRECIPITATION IS EXPECTED TO SWITCH
OVER TO ALL SNOW AT KLSE AROUND 00Z WITH IFR CONDITIONS EXPECTED.
PRECIPITATION WILL FINALLY MOVE EAST OF THE TAF SITE LAT THIS
EVENING WITH MVFR CONDITIONS EXPECTED. WILL HAVE TO KEEP A CLOSE
WATCH ON FREEZING DRIZZLE POTENTIAL THIS EVENING AS ICE ALOFT IS
LOST AND LOW LEVEL MOISTURE AND WEAK LIFT LINGERS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
313 AM CST SUN NOV 11 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...WETENKAMP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
557 AM CST SUN NOV 11 2012
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
313 AM CST SUN NOV 11 2012
THE MAIN FOCUS THROUGH EARLY NEXT WEEK IS WITH THE CHANGE OVER
FROM RAIN TO FROZEN PRECIPITATION TODAY AND HOW COLD IT WILL BE
THE NEXT FEW DAYS.
BROAD UPPER LEVEL TROUGHING HAS MOVED INTO THE CENTRAL PLAINS AND
UPPER MISSISSIPPI RIVER VALLEY WITH THE MAIN EMBEDDED CLOSED LOW
CURRENTLY LOCATED IN NORTHEAST MONTANA. AT THE SURFACE...A LOW
PRESSURE SYSTEM HAS MADE IT INTO NORTHERN MINNESOTA WITH A COLD
FRONT TRAILING TO THE SOUTH ALONG AND JUST TO THE WEST OF I-35
FROM MINNESOTA DOWN TO NORTHWEST MISSOURI. HIGH TEMPERATURES HAVE
LIKELY ALREADY BEEN HIT FOR THE DAY WITH COLDER AIR MOVING IN THIS
MORNING. TWO MAIN CORRIDORS OF RAIN SHOWERS AND ISOLATED
THUNDERSTORMS HAVE SET UP WITH ONE EASTERN BAND IN WISCONSIN BEING
IN THE MIDDLE OF THE STRONGEST LOW LEVEL MOISTURE TRANSPORT AND
THE OTHER ASSOCIATED WITH THE SURFACE COLD FRONT. INSTABILITY IS
RATHER LIMITED WITH 11.07Z RAP ANALYSIS SHOWING LESS THAN 250 J/KG
ACROSS THE ENTIRE AREA...SO THUNDERSTORMS SHOULD REMAIN FAIRLY
ISOLATED.
WITH THE EASTERN BAND OF RAIN BEING TO THE EAST OF THE FORECAST
AREA...THE FOCUS IS MORE SO WITH THE WESTERN BAND THAT WILL MOVE IN
ALONG WITH THE COLD FRONT THIS MORNING. 11.00Z NAM/GFS CROSS
SECTIONS RUNNING FROM WEST TO EAST ACROSS THE REGION SHOW
INCREASING FRONTOGENESIS WITH DEEPER LIFT COMING IN AS A RESULT
THIS MORNING ALONG AND BEHIND THE FRONT. WOULD EXPECT THE SCATTERED
COVERAGE TO THE RAIN TO BECOME MORE WIDESPREAD BY MID MORNING.
WITH A PROLONGED PERIOD OF RAIN LASTING THROUGH MUCH OF
TODAY...EXPECT TO SEE RAINFALL AMOUNTS RANGING FROM AROUND A HALF
INCH ON UP TO AN INCH AND A HALF WITH THE HIGHER AMOUNTS MORE
LIKELY ACROSS WESTERN WISCONSIN.
WITH MUCH OF THE PRECIPITATION OCCURRING AFTER THE SURFACE COLD
FRONT COMES THROUGH...IT APPEARS LIKELY THAT TEMPERATURES WILL BE
ABLE TO COOL QUICKLY ENOUGH THAT A CHANGE OVER TO FROZEN
PRECIPITATION WILL OCCUR. 11.00Z NAM/GFS AND 11.06Z RAP SOUNDINGS
SHOW A RAPID NEAR SURFACE LAYER COOLING BEHIND THE FRONT WHILE A
WARM LAYER REMAINS AROUND 850MB. THIS COULD LEAD TO A BRIEF
TRANSITION PERIOD WHERE THE WARM LAYER WILL BE WARM ENOUGH AT +2
TO +4C WITH A NEAR SURFACE COLD LAYER DROPPING DOWN TO AROUND -7C
THAT SOME SLEET AND/OR FREEZING RAIN MAY OCCUR. THE WARM LAYER
RAPIDLY COOLS THOUGH AND CATCHES UP TO WHERE THE FULL THERMAL
PROFILE IS SUB-FREEZING WHILE PRECIPITATION IS STILL OCCURRING.
THIS PERIOD OF ALL SNOW APPEARS TO BE BRIEF AS WELL AT AN HOUR TO
3 HOURS OR SO BEFORE DRIER AIR MOVES IN AND ENDS THE PRECIPITATION.
GIVEN THE SHORT RESIDENCE TIME OF THE FROZEN PRECIPITATION...AM
NOT EXPECTING MUCH IN THE WAY OF ACCUMULATION OF SNOW WITH UP TO A
HALF INCH FALLING. IMPACTS FROM ANY SLEET OR FREEZING RAIN ARE
EXPECTED TO BE MINIMAL AFTER A PROLONGED PERIOD OF RAIN FALLING
BEFORE IT THOUGH SOME SLICK SPOTS CAN NOT BE COMPLETELY RULED OUT.
A COOL CANADIAN AIR MASS WITH THEN DROP DOWN INTO THE REGION
SUNDAY NIGHT INTO MONDAY WITH 850MB TEMPERATURES DROPPING DOWN TO
AROUND -16C BY MONDAY MORNING. WITH SOME BRIEF CLEARING EXPECTED
OVERNIGHT ACROSS NORTHEAST IOWA...COULD SEE SOME SPOTS DROP INTO
THE TEENS. HIGH TEMPERATURES WILL THEN STRUGGLE TO GET ABOVE
FREEZING ON MONDAY WITH THE CORE OF THE COLDEST AIR OVERHEAD ALONG
WITH CLOUDY SKIES. WITH THE LOW LEVEL MOISTURE BEING IN THE
DENDRITIC GROWTH ZONE BUT LIFT BEING WEAK...EXPECT TO SEE FLURRIES
THROUGH MUCH OF THE DAY BEFORE THE TROUGH PROPAGATES TO THE EAST
INTO THE GREAT LAKES. A GRADUAL WARMING TREND WILL THEN KICK OFF
ON TUESDAY WITH LOW LEVEL SOUTHWESTERLY WINDS BRINGING WARMER AIR
INTO THE REGION. THE 11.00Z GFS/ECMWF DO SHOW SOME PRECIPITATION
FORMING ALONG THE NORTHERN FRINGE OF THE LOW LEVEL ADVECTION
TUESDAY NIGHT WHICH SHOULD REMAIN TO THE NORTHWEST OF THE FORECAST
AREA.
.LONG TERM...WEDNESDAY THROUGH SATURDAY
313 AM CST SUN NOV 11 2012
HIGH PRESSURE SETS UP ACROSS THE EASTERN HALF OF THE US ON
WEDNESDAY AND LINGERS THROUGH NEXT WEEKEND AND SHOULD LEAVE DRY
CONDITIONS THROUGH THE PERIOD. WITH THE UPPER MISSISSIPPI RIVER
VALLEY BEING ON THE WESTERN PERIPHERY OF THE RIDGE THERE SHOULD BE
SOUTHERLY SURFACE TO LOW LEVEL WINDS THAT WILL KEEP TEMPERATURES
AT ABOUT NORMAL.
&&
.AVIATION...TODAY AND TONIGHT
557 AM CST SUN NOV 11 2012
A STRONG COLD FRONT WILL PUSH ACROSS THE AREA TODAY BRINGING RAIN
TO THE TAF SITES THIS MORNING...SWITCHING OVER TO A MIX OF SLEET
AND SNOW THIS AFTERNOON WITH A SWITCH OVER TO ALL SNOW LATE IN THE
AFTERNOON INTO THE EARLY EVENING HOURS. PLAN ON IFR CONDITIONS
EARLY THIS MORNING AT KRST WITH CLOUD BASES AT 500 FT ALONG WITH LIGHT
RAIN AND BR. IFR CONDITIONS WILL DEVELOP AT KLSE AROUND 14Z AS
RAIN AND LOW CLOUDS MOVE IN WITH CLOUD BASES LOWERING TO AROUND
900 FT. WINDS WILL SWITCH TO THE WEST THEN NORTHWEST AS THE FRONT
MOVES IN. LOOK FOR THE RAIN TO SWITCH OVER TO A MIX OF SLEET AND
SNOW AROUND 19Z AT KRST AND AROUND 22Z AT KLSE. THE PRECIPITATION
SHOULD SWITCH OVER TO ALL SNOW AT KRST BY 21Z WITH IFR CONDITIONS
PERSISTING...WITH CEILINGS AROUND 600 FT AND VISIBILITIES REDUCED
TO AROUND 3SM IN SNOW. THE PRECIPITATION IS EXPECTED TO SWITCH
OVER TO ALL SNOW AT KLSE AROUND 00Z WITH IFR CONDITIONS EXPECTED.
PRECIPITATION WILL FINALLY MOVE EAST OF THE TAF SITE LAT THIS
EVENING WITH MVFR CONDITIONS EXPECTED. WILL HAVE TO KEEP A CLOSE
WATCH ON FREEZING DRIZZLE POTENTIAL THIS EVENING AS ICE ALOFT IS
LOST AND LOW LEVEL MOISTURE AND WEAK LIFT LINGERS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
313 AM CST SUN NOV 11 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...WETENKAMP
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1133 AM MST SUN NOV 11 2012
.UPDATE
ISSUED AT 1133 AM MST SUN NOV 11 2012
WEBCAMS ACROSS THE AREA SHOW SNOW CONTINUING OVER TELLURIDE AND
VAIL PASS. LATEST HRRR MODEL DATA ALSO INDICATES MORE BANDS SETTING
UP THIS AFTERNOON AIDED BY FAVORABLE OROGRAPHICS. VISIBLE SATELLITE
IMAGERY CORROBORATES THIS WITH SOME ENHANCED TOPS SHOWING UP OVER
THE MOUNTAINS IN COLORADO. AS SUCH...WILL KEEP WARNINGS AND
ADVISORIES IN PLACE WITH ANOTHER 2 TO 4 INCHES OF NEW SNOW
POSSIBLE THROUGH THIS EVENING. FORECAST LOOKS GOOD ASIDE FROM SOME
MINOR TWEAKS TO SKY GRID.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 322 AM MST SUN NOV 11 2012
THE SYNOPTIC PICTURE IS SIMPLE WHILE THE DETAILS REMAIN COMPLEX.
THE SECOND FRIGID COLD FRONT WORKED THROUGH THE REGION OVERNIGHT
BRINGING WIDESPREAD SNOWFALL MAINLY TO THE CENTRAL ZONES. IN NW
FLOW 700 MB TEMPERATURES DROP TO -16C BY MIDDAY SO ANY AVAILABLE
MOISTURE THAT ENCOUNTERS ANY LIFT AT ALL WILL EFFICIENTLY PRODUCE
BIG FLUFFY DENDRITIC SNOW CRYSTALS. IN ADDITION THE MODELS SHOW A
DEFORMATION ZONE PASSING THROUGH NW-WEST CENTRAL COLORADO THIS
MORNING INTO EARLY AFTERNOON. SO MICROPHYSICS...OROGRAPHICS...AND
SOME DYNAMICS ALL COMBINE TO STACK UP SNOWFALL TODAY OVER THE
CENTRAL AND NORTHERN CO MTNS AND ADJOINING VALLEYS.
IN THE NW SAN JUAN MTNS THIS EARLY MORNING...RADAR VAD WINDS
INDICATED NORTH AT 15KTS AT 11KFT AND MONTROSE AND TELLURIDE HAVE
BEEN SNOWING FOR SEVERAL HOURS THIS EARLY MORNING. MONTROSE MAY
REACH SNOW ADVISORY CRITERIA AND THE UNCOMPAHGRE GORGE COULD BE
GETTING LARGE ACCUMULATIONS THIS EARLY MORNING. SO EXTENDED THE
WARNING FOR ZONE 18 UNTIL 6 PM WITH HIGHWAY 550 AND 145 TRAVEL
EXPECTED TO BE IMPACTED.
SNOTEL SITES INDICATE STORM TOTALS OF TWO FEET ON THE FLATTOPS AND
GRAND MESA AND OVER SCHOFIELD PASS IN THE WEST ELKS. TOWER SITE IN
THE PARK RANGE HAS APPROACHED A FOOT NEW THIS EARLY MORNING SO WE
UPGRADED THE ADVISORY FOR ZONE 4 TO WARNING. WITH THE WEAK
DISTURBANCE PASSING TO THE EAST THIS AFTERNOON AND WARM ADVECTION
BEGINNING ALOFT...ALL SNOW HIGHLIGHTS END AT 6 PM.
SUNDAY NIGHT WILL BE FRIGID WITH NEW RECORD LOWS POSSIBLE AT ALL
LOCATIONS. ICE FOG IS POSSIBLE OVERNIGHT MAINLY IN THE VALLEY
BOTTOMS AND NORTH SLOPES OF MOUNTAINS. AS WARM AIR POURS IN
ALOFT... FORECAST SOUNDINGS SHOW A NEAR ISOTHERMAL LAYER FROM THE
SURFACE UP TO 650MB OR 12KFT ELEVATION. THUS EXPOSED HIGH MTN
SLOPES EVEN NEAR TIMBERLINE MAY NOT BE AS COLD AS THE VALLEY
BOTTOMS.
MONDAY THE VALLEYS WILL REMAIN STRONGLY CAPPED WHILE THE SLOPES
SHOW A WARMING TREND. HIGH CLOUDS INVADE ESPECIALLY ACROSS THE
NORTHERN ZONES AHEAD OF A WEAK ZONAL DISTURBANCE.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 322 AM MST SUN NOV 11 2012
A WEAK WAVE PASSES MONDAY NIGHT AND CLIPS THE NORTHERN ZONES
TRIGGERING A FEW LIGHT SNOW SHOWERS. OTHERWISE LITTLE IMPACT
EXPECTED FROM THIS SYSTEM OUTSIDE OF AN INCREASE IN CLOUD COVER
INTO TUESDAY MORNING. THIS SHOULD HELP TO MODERATE LOWS A BIT OVER
THE POTENTIAL RECORD COLD EXPECTED MONDAY MORNING.
AS THIS SYSTEM EXITS TUESDAY MORNING...SHRTWV RIDING WILL BUILD IN
AND BRING CLEAR/DRY CONDITIONS THROUGH THURSDAY. VALLEY INVERSIONS
WILL BE SLOW TO BREAK...SO WILL BE SHAVING A FEW DEGREES OF MAX
TEMPS UNTIL FLOW ALOFT SWINGS BACK TO THE SOUTHWEST LATE THURSDAY.
MODELS CONTINUE TO SLOW DOWN AND BACK OFF THE NEXT SYSTEM THAT IS
NOW DELAYED INTO THE FRIDAY/SATURDAY TIME FRAME. APPEARS THAT WE
WILL SEE A SERIES OF WEAK WAVES KICKING OUT OF THE BASE OF THE
TROUGH...WITH EACH SYSTEM LOSING ENERGY AS IT MOVES ACROSS THE
SOUTHWEST U.S. BIGGEST IMPACT AT THIS TIME WILL BE BETTER MIXING
TO ALLOW WARMER AIR ALOFT TO MIX INTO THE VALLEYS AND BRING
LOCALLY BREEZY CONDITIONS TO THE AREA ALONG WITH A FEW MOUNTAIN
SHOWERS. TEMPS WILL BE RETURNING TO MORE SEASONAL NORMS AS THE
WEEK CLOSES...EVEN WITH THE INCREASED CLOUD COVER AND POTENTIAL
FOR SHOWERS IN THE REGION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z NOON MONDAY)
ISSUED AT 936 AM MST SUN NOV 11 2012
OFF AND ON SNOW AND LOW CLOUDS ARE EXPECTED FOR KASE KEGE AND KSBS
WITH MVFR TO IFR CIGS AND VIS THROUGH THE EARLY AFTERNOON HOURS.
SOME CLEARING IS EXPECTED AFTER THAT WITH POSSIBLY A RETURN TO
SOME SNOWSHOWERS IN THE EARLY EVENING HOURS.
SOME FOG WAS REPORTED EARLIER THIS MORNING BUT HAS BURNED OFF WITH
REMAINING TAF SITES EXPECTED TO REMAIN VFR WITH SOME MID TO HIGH
CLOUDS HANGING AROUND.
SOME MORNING FOG WILL BE POSSIBLE FOR MANY VALLEY LOCATIONS
TOMORROW MORNING WITH VIS DROPPING TO LESS THAN A MILE AT TIMES.
THE FOG SHOULD DISSIPATE BETWEEN 0900 AND 1000.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WARNING UNTIL 6 PM MST THIS EVENING FOR COZ004-009-
013-018.
WINTER WEATHER ADVISORY UNTIL 6 PM MST THIS EVENING FOR COZ003-
005-008-010.
UT...NONE.
&&
$$
UPDATE...TGR
SHORT TERM...JOE
LONG TERM...JDC
AVIATION...TGR
AREA FORECAST DISCUSSION
NWS LINCOLN IL
300 PM CST SUN NOV 11 2012
.DISCUSSION...
ISSUED 300 PM CST SUN NOV 11 2012
VIGOROUS SYSTEM APPROACHING CENTRAL AND SOUTHEAST ILLINOIS HAS
RESULTED IN STRONG SOUTHERLY WINDS TODAY...WITH NUMEROUS GUSTS
OVER 40 MPH ACROSS CENTRAL ILLINOIS. A FEW GUSTS OF 50-55 MPH HAVE
BEEN REPORTED AS WELL. COLD FRONT IS ALREADY MAKING STEADY
PROGRESS ACROSS THE FORECAST AREA...CROSSING THE IL RIVER VALLEY
AT THE MOMENT. MAIN FORECAST CONCERN TODAY REVOLVES AROUND
WIND...PRECIPITATION...TEMPERATURES EITHER SIDE OF TONIGHT/S
FROPA. OTHERWISE...RATHER BENIGN...ALBEIT COOLER THAN NORMAL
CONDITIONS...ARE EXPECTED FOR THE NEXT SEVERAL DAYS.
12Z MODELS SHOW SPREAD IN THE MOISTURE/THERMAL FIELDS TONIGHT
INVOF FROPA...AND AGAIN WITH LOWER AMPLITUDE WAVES IN THE MOSTLY
ZONAL FLOW LATER IN THE WEEK. OTHERWISE...AGREEMENT IS GOOD. IN THE
NEAR TERM...PLAN TO USE ACTUAL OBSERVATIONS AND EXTRAPOLATION
RATHER THAN ANY ONE MODEL SOLUTION. FURTHER OUT...AN ENSEMBLE
BLEND SHOULD CONTINUE TO BE THE BEST COURSE OF ACTION UNTIL THE
SPREAD DIMINISHES A BIT.
SHORT TERM...TONIGHT THROUGH WEDNESDAY...FRONT IS CURRENTLY MOVING
MORE QUICKLY THAN MOST OF THE MODELS INDICATED AND SEE NO REASON
WHY THIS WILL NOT CONTINUE TO BE THE CASE. WILL BE CANCELING THE
WESTERN EXTENT OF THE WIND ADVISORY AT 4 PM AS WINDS HAVE BEEN AND
SHOULD CONTINUE TO FALL BELOW ADVISORY LEVELS WITH FROPA. THE BULK
OF THE PRECIPITATION IS STILL EXPECTED ALONG AND BEHIND THE
FRONT...ASSOCIATED WITH STRONG MID LEVEL FRONTOGENESIS AND THE
APPROACH OF THE MAIN UPPER WAVE/JET. WHILE IT STILL LOOKS AS
THOUGH THE BULK OF THE PRECIPITATION SHOULD BE OVER BY THE TIME IT
IS COLD ENOUGH TO SNOW...IT SHOULD BE NOTED THAT THE LATEST NAM
AND RAP HOLD ONTO DEEPER MOISTURE INTO THE OVERNIGHT HOURS AND
WOULD POSE A GREATER SNOW RISK. HOWEVER...UPSTREAM TRENDS CONTINUE
TO AGREE WITH PREVIOUS EXPECTATION THAT THE PRECIPITATION SHOULD
END FOR THE MOST PART BEFORE IT IS COLD ENOUGH FOR SNOW. WE WILL
NEED TO KEEP AN EYE ON THESE TRENDS THOUGH...ESPECIALLY DUE TO THE
FASTER MOVEMENT OF THE FRONT AND ARRIVAL OF THE COLD AIR.
PRECIPITATION WILL BE OVER BY EARLY MONDAY AND A CHILLY AREA OF
HIGH PRESSURE WILL BUILD ACROSS THE AREA INTO MID WEEK. THIS
SURFACE HIGH...ASSOCIATED DRY AIRMASS...AND MOSTLY NEUTRAL UPPER
LEVEL FLOW SHOULD PRODUCE QUIET WEATHER THROUGH THE PERIOD.
LONG TERM...THURSDAY THROUGH SUNDAY...FOR THE MOST PART...THE
MODELS SUPPORT PREDOMINANTLY HIGH PRESSURE AT THE SURFACE AND
ZONAL/NEUTRAL UPPER LEVEL FLOW THROUGH THE WEEKEND. THE LOW LEVEL
FLOW TURNING SOUTHERLY AND GRADUALLY RISING HEIGHTS SUPPORT A SLOW
MODERATION IN TEMPERATURES...ALTHOUGH THEY WILL STILL BE COOL.
SOME SHORT WAVE ENERGY MAY IMPACT THE AREA FROM TIME TO TIME...BUT
THERE IS NOT ENOUGH OF A MODEL CONSENSUS IN THE TIMING/TRACK OF
ANY OF THESE DISCRETE WAVES TO WARRANT CARRYING POPS AT ANY POINT
IN THE EXTENDED RANGE OF THE FORECAST.
BAK
&&
.AVIATION...
ISSUED 1215 PM CST SUN NOV 11 2012
AVIATION CONCERNS REMAIN WITH THE VERY STRONG WINDS ACROSS ALL ILX
TERMINALS TODAY. SOUTHERLY WINDS 25-25KTS COMMON WITH GUSTS COMMON
OVER 40 KTS. VFR DOMINATING AHEAD OF FRONT. FRONT ALONG THE MISS
RIVER VALLEY AND TIMED TO PASS THRU FROM WEST TO EAST BTWN 00 AND
04Z. SHARP GRADIENT AND BAROCLINIC ZONE AND VERY SUDDEN WINDSHIFT
FROM SOUTHERLY TO WESTERLY WITH THE BOUNDARY. SHOWERS ALONG AND
BEHIND THE FRONT INTO THE EARLY MORNING HOURS LIKELY FOR MOST OF
CENTRAL IL. FAIRLY DEFINED CLEARING LINE EXPECTED FOR THE MORNING
WITH THE DRY SLOT SHOWING UP ON VIS SAT IMAGERY OVER THE PLAINS
TODAY.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 8 PM CST THIS EVENING FOR ILZ038-042>046-
051>057-061>063-066>068-071>073.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1221 PM CST SUN NOV 11 2012
.DISCUSSION...
ISSUED 1039 AM CST SUN NOV 11 2012
WARM AIR ADVECTION AHEAD OF THE APPROACHING COLD FRONT EFFECTIVELY
BUMPING TEMPS UP A BIT IN THE FAR WEST. HAVE ADJUSTED THE FORECAST
MAX TEMPS...THOUGH IT WILL NOT BE LONG BEFORE THE MAX IS HIT IN
THAT REGION. FRONT RAPIDLY MOVING ACROSS THE MISS RIVER VALLEY WITH
PLENTY OF PRECIP BEHIND IT AND A RATHER SHARP DROP IN
TEMPERATURES EXPECTED FOR THE LATE AFTERNOON/EVENING HOURS. VERY
LITTLE THUNDER ASSOCIATED WITH THE RAINFALL. THE MAIN ISSUE FOR
THE FORECAST REMAINS VERY STRONG WINDS AHEAD OF THE FRONT AS THE
PRESSURE GRADIENT TIGHTENS AND 50 KT WINDS JUST OFF THE SFC MIX
DOWN THROUGH THIS MORNINGS INVERSION. WIND ADVISORY FOR ENTIRE
AREA WILL MOST DEFINITELY REMAIN. ZONE UPDATE ALREADY SENT.
&&
.AVIATION...
ISSUED 1215 PM CST SUN NOV 11 2012
AVIATION CONCERNS REMAIN WITH THE VERY STRONG WINDS ACROSS ALL ILX
TERMINALS TODAY. SOUTHERLY WINDS 25-25KTS COMMON WITH GUSTS COMMON
OVER 40 KTS. VFR DOMINATING AHEAD OF FRONT. FRONT ALONG THE MISS
RIVER VALLEY AND TIMED TO PASS THRU FROM WEST TO EAST BTWN 00 AND
04Z. SHARP GRADIENT AND BAROCLINIC ZONE AND VERY SUDDEN WINDSHIFT
FROM SOUTHERLY TO WESTERLY WITH THE BOUNDARY. SHOWERS ALONG AND
BEHIND THE FRONT INTO THE EARLY MORNING HOURS LIKELY FOR MOST OF
CENTRAL IL. FAIRLY DEFINED CLEARING LINE EXPECTED FOR THE MORNING
WITH THE DRY SLOT SHOWING UP ON VIS SAT IMAGERY OVER THE PLAINS
TODAY.
HJS
&&
.PREV DISCUSSION...
ISSUED 246 AM CST SUN NOV 11 2012
BIGGEST CHALLENGES THIS PACKAGE ARE WINDS TODAY/THIS EVENING AND
MODEL SPREAD TOWARD THE END OF THE WEEK.
SHORT TERM...TODAY AND TONIGHT
LOOKS LIKE A WINDY DAY ACROSS CENTRAL AND SOUTHEAST ILLINOIS.
THERE IS SOME SPREAD IN FORECAST WIND SPEEDS. STRONGER NAM SEEMS
MORE REASONABLE GIVEN MATCHING UP CURRENT WINDS AND THE HIGHER
RESOLUTION IN THE BOUNDARY LAYER COMPARED TO THE GLOBAL MODELS.
FORECAST GRADIENT WINDS SUGGEST SUSTAINED SPEEDS SHOULD SURPASS
ADVISORY LEVELS. EVEN THOUGH THE GFS GRIDS DO NOT INDICATED AS
HIGH OF SPEEDS AS THE NAM AND HIGH RES MODELS...MAV GUIDANCE IS
INDICATING ADVISORY CRITERIA. NAM MODEL SOUNDINGS SHOW 40+ KTS
SEVERAL HUNDRED FEET OFF THE SURFACE AND SUFFICIENT MIXING OCCURS...THE
GUST CRITERIA OF 45 KTS MAY ALSO BE SURPASSED. CLOUDS MAY LIMIT
MIXING SOME...BUT IT WONT TAKE MUCH TO TAP INTO THE HIGHER
MOMENTUM OFF THE SURFACE. 04Z HRRR SHOWS 40-50 KT GUSTS ACROSS
MOST OF THE AREA BY 19Z. LOOKS LIKE HIGHEST SPEEDS SHOULD DEVELOP
BY LATE MORNING OVER WEST CENTRAL IL AND THEN SPREAD QUICKLY
SOUTHEAST THROUGH MIDDAY AND EARLY AFTERNOON. WILL BE ISSUING WIND
ADVISORY FOR ENTIRE FORECAST AREA.
WINDS SHOULD DECREASE FROM NORTHWEST TO SOUTHEAST DURING THE
EVENING SHORTLY AFTER COLD FRONTAL PASSAGE. SPEAKING OF THE FRONT...
00Z MODEL SUITE IN GOOD AGREEMENT ON TIMING OF INCOMING COLD
FRONT AND POST-FRONTAL PRECIP. HOWEVER...MOST OF THE MODELS ARE
NOT HANDLING THE PRE-FRONTAL PRECIP CURRENTLY ALONG AND WEST OF
THE MISSISSIPPI IN THE WARM SECTOR. LATEST ECMWF(00Z) DOES HINT AT
AN AREA OF PRECIP OVER WEST CENTRAL IL AT 12Z. ORIGINALLY WAS
THINKING THAT ANY PRECIP CHANCE WOULD WAIT FOR THE FRONT...NOT
REACHING WESTERN FORECAST AREA UNTIL LATE MORNING...BUT WITH ONGOING
SHOWERS WILL INCLUDE A CHANCE OF RAIN FOR THE ENTIRE MORNING OVER
THE WEST.
LOOKS LIKE A ANAFRONT STRUCTURED FRONT AND THE BULK OF PRECIP SHOULD BE
MOSTLY ALONG AND BEHIND THE BOUNDARY. PRECIP WATER REMAINS WELL
ABOVE CLIMATOLOGY...99 PERCENTILE FOR NOVEMBER...AND ALTHOUGH THE
PERIOD OF RAIN AT ANY ONE SPOT SHOULDNT BE MORE THAN 12
HOURS...QPF SHOULD APPROACH AN INCH IN MOST AREAS WITH LOCALLY
HIGHER AMOUNTS. DESPITE MEAGER INSTABILITY...SHEAR IS IMPRESSIVE
AND MAY BE SUFFICIENT FOR ISOLATED EMBEDDED THUNDER BEHIND THE
FRONT WHICH COULD LOCALLY ENHANCE THE RAINFALL RATES.
STRONG COLD ADVECTION SURGES INTO THE AREA BEHIND THE FRONT AND
THERE MAY BE A BRIEF PERIOD OF A MIX OR A CHANGE TO SNOW BEFORE
THE PRECIP ENDS EARLY MONDAY. GROUND TEMPS SHOULD BE WARM ENOUGH
TO LIMIT ANY ACCUMULATION.
LONG TERM...MONDAY THROUGH SATURDAY
AFTER PRECIP MOVES OUT MONDAY MORNING...BIG STORY WILL BE THE
COLD ADVECTION. TEMPS WILL BE SUPPRESSED WITH HIGHS ON MONDAY
BEING SOME 20-25 DEGREES COOLER THAN SUNDAY IN MOST LOCATIONS AND
WITH BRISK WEST WINDS...WIND CHILLS WILL STAY OR FALL INTO THE 20S
AND 30S. CLEARING SHOULD SPREAD ACROSS THE AREA EARLY MONDAY. HIGH
PRESSURE CENTERS OVER ILLINOIS ON TUESDAY AND TUESDAY MORNING
SHOULD HAVE GOOD RADIATION AL COOLING CONDITIONS WITH A HARD FREEZE
LIKELY FOR MOST OF CENTRAL AND SOUTHEAST ILLINOIS.
850 MB TEMPS SLOWLY REBOUND AS THE AIR MASS MODERATES AFTER
TUESDAY AND TEMPS SHOULD REACH CLOSE TO NORMAL FOR THE LATER PART
OF THE WEEK.
MODEL SPREAD INCREASES SIGNIFICANTLY IN THE NAEFS AND OPERATIONAL
MODELS FOR THE LATER HALF OF THE WEEK WITH GENERALLY WEAK FLOW AND
ABOVE NORMAL HEIGHTS. MOST LIKELY SCENARIO SUGGESTS HIGH PRESSURE
RIDGING INTO IL FROM THE NORTHEAST KEEPING DRY WEATHER IN PLACE
INTO THE WEEKEND.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 8 PM CST THIS EVENING FOR ILZ027>031-036>038-
040>057-061>063-066>068-071>073.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1045 AM CST SUN NOV 11 2012
.DISCUSSION...
ISSUED 1039 AM CST SUN NOV 11 2012
WARM AIR ADVECTION AHEAD OF THE APPROACHING COLD FRONT EFFECTIVELY
BUMPING TEMPS UP A BIT IN THE FAR WEST. HAVE ADJUSTED THE FORECAST
MAX TEMPS...THOUGH IT WILL NOT BE LONG BEFORE THE MAX IS HIT IN
THAT REGION. FRONT RAPIDLY MOVING ACROSS THE MISS RIVER VALLEY WITH
PLENTY OF PRECIP BEHIND IT AND A RATHER SHARP DROP IN
TEMPERATURES EXPECTED FOR THE LATE AFTERNOON/EVENING HOURS. VERY
LITTLE THUNDER ASSOCIATED WITH THE RAINFALL. THE MAIN ISSUE FOR
THE FORECAST REMAINS VERY STRONG WINDS AHEAD OF THE FRONT AS THE
PRESSURE GRADIENT TIGHTENS AND 50 KT WINDS JUST OFF THE SFC MIX
DOWN THROUGH THIS MORNINGS INVERSION. WIND ADVISORY FOR ENTIRE
AREA WILL MOST DEFINITELY REMAIN. ZONE UPDATE ALREADY SENT.
HJS
&&
.AVIATION...
ISSUED 515 AM CST SUN NOV 11 2012
MAIN CONCERNS THIS FORECAST PERIOD WILL BE WITH THE STRONG SOUTH
WINDS TODAY...TIMING OF FROPA THIS EVENING AND ASSOCIATED RAIN
CHANCES ALONG IT AND POTENTIAL FOR A PERIOD OF MVFR/IFR CIGS
TONIGHT AS MUCH COLDER AIR FILTERS INTO THE AREA. 12Z ILX SOUNDING
SHOWING 50-55 KTS AROUND THE 2000 FOOT LAYER...SO WILL CONTINUE
WITH THE LLWS FOR THE NEXT COUPLE OF HOURS.
COLD FRONT CURRENTLY JUST WEST OF DES MOINES AND SHOULD CROSS THE
MISSISSIPPI RIVER BY 21Z. WE HAVE HAD SOME ISOLD SHOWERS DEVELOP
IN A BROAD WARM ADVECTION PATTERN ACROSS THE MID-MISSISSIPPI VALLEY
OVERNIGHT...WEST OF THE TAF SITES. MOST OF THAT ACTIVITY SHOULD
REMAIN WEST OF OUR AREA UNTIL THE FRONT MAKES SOME EASTWARD PROGRESS
LATER TODAY. SOUTHERLY WINDS OF 20 TO 25 KTS...WITH OCCASIONAL GUSTS
UP TO 40 KTS WILL PREVAIL OVER THE FORECAST AREA TODAY BEFORE WINDS
SWITCH INTO THE WEST EARLY THIS EVENING AT PIA AND SPI...AND BY 03Z
OVER AT KCMI. WE SHOULD SEE CIGS GRADUALLY LOWER TODAY AND DROP TO
MVFR CATEGORY BY LATE AFTN OR EARLY EVENING ALONG AND JUST BEHIND
THE COLD FRONT. FORECAST SOUNDINGS SUGGEST ABOUT A 3-6 HOUR PERIOD
OF MVFR CIGS AND POSSIBLY LOWER IN SOME OF THE HEAVIER RAINS
TONIGHT. THE PRECIP SHOULD BE SHIFTING EAST OF THE TAF SITES BY
AROUND 09Z WITH CIGS AND VSBYS SLOWLY IMPROVING IN THE 09Z-12Z TIME
FRAME.
SMITH
&&
.PREV DISCUSSION...
ISSUED 246 AM CST SUN NOV 11 2012
BIGGEST CHALLENGES THIS PACKAGE ARE WINDS TODAY/THIS EVENING AND
MODEL SPREAD TOWARD THE END OF THE WEEK.
SHORT TERM...TODAY AND TONIGHT
LOOKS LIKE A WINDY DAY ACROSS CENTRAL AND SOUTHEAST ILLINOIS.
THERE IS SOME SPREAD IN FORECAST WIND SPEEDS. STRONGER NAM SEEMS
MORE REASONABLE GIVEN MATCHING UP CURRENT WINDS AND THE HIGHER
RESOLUTION IN THE BOUNDARY LAYER COMPARED TO THE GLOBAL MODELS.
FORECAST GRADIENT WINDS SUGGEST SUSTAINED SPEEDS SHOULD SURPASS
ADVISORY LEVELS. EVEN THOUGH THE GFS GRIDS DO NOT INDICATED AS
HIGH OF SPEEDS AS THE NAM AND HIGH RES MODELS...MAV GUIDANCE IS
INDICATING ADVISORY CRITERIA. NAM MODEL SOUNDINGS SHOW 40+ KTS
SEVERAL HUNDRED FEET OFF THE SURFACE AND SUFFICIENT MIXING OCCURS...THE
GUST CRITERIA OF 45 KTS MAY ALSO BE SURPASSED. CLOUDS MAY LIMIT
MIXING SOME...BUT IT WONT TAKE MUCH TO TAP INTO THE HIGHER
MOMENTUM OFF THE SURFACE. 04Z HRRR SHOWS 40-50 KT GUSTS ACROSS
MOST OF THE AREA BY 19Z. LOOKS LIKE HIGHEST SPEEDS SHOULD DEVELOP
BY LATE MORNING OVER WEST CENTRAL IL AND THEN SPREAD QUICKLY
SOUTHEAST THROUGH MIDDAY AND EARLY AFTERNOON. WILL BE ISSUING WIND
ADVISORY FOR ENTIRE FORECAST AREA.
WINDS SHOULD DECREASE FROM NORTHWEST TO SOUTHEAST DURING THE
EVENING SHORTLY AFTER COLD FRONTAL PASSAGE. SPEAKING OF THE FRONT...
00Z MODEL SUITE IN GOOD AGREEMENT ON TIMING OF INCOMING COLD
FRONT AND POST-FRONTAL PRECIP. HOWEVER...MOST OF THE MODELS ARE
NOT HANDLING THE PRE-FRONTAL PRECIP CURRENTLY ALONG AND WEST OF
THE MISSISSIPPI IN THE WARM SECTOR. LATEST ECMWF(00Z) DOES HINT AT
AN AREA OF PRECIP OVER WEST CENTRAL IL AT 12Z. ORIGINALLY WAS
THINKING THAT ANY PRECIP CHANCE WOULD WAIT FOR THE FRONT...NOT
REACHING WESTERN FORECAST AREA UNTIL LATE MORNING...BUT WITH ONGOING
SHOWERS WILL INCLUDE A CHANCE OF RAIN FOR THE ENTIRE MORNING OVER
THE WEST.
LOOKS LIKE A ANAFRONT STRUCTURED FRONT AND THE BULK OF PRECIP SHOULD BE
MOSTLY ALONG AND BEHIND THE BOUNDARY. PRECIP WATER REMAINS WELL
ABOVE CLIMATOLOGY...99 PERCENTILE FOR NOVEMBER...AND ALTHOUGH THE
PERIOD OF RAIN AT ANY ONE SPOT SHOULDNT BE MORE THAN 12
HOURS...QPF SHOULD APPROACH AN INCH IN MOST AREAS WITH LOCALLY
HIGHER AMOUNTS. DESPITE MEAGER INSTABILITY...SHEAR IS IMPRESSIVE
AND MAY BE SUFFICIENT FOR ISOLATED EMBEDDED THUNDER BEHIND THE
FRONT WHICH COULD LOCALLY ENHANCE THE RAINFALL RATES.
STRONG COLD ADVECTION SURGES INTO THE AREA BEHIND THE FRONT AND
THERE MAY BE A BRIEF PERIOD OF A MIX OR A CHANGE TO SNOW BEFORE
THE PRECIP ENDS EARLY MONDAY. GROUND TEMPS SHOULD BE WARM ENOUGH
TO LIMIT ANY ACCUMULATION.
LONG TERM...MONDAY THROUGH SATURDAY
AFTER PRECIP MOVES OUT MONDAY MORNING...BIG STORY WILL BE THE
COLD ADVECTION. TEMPS WILL BE SUPPRESSED WITH HIGHS ON MONDAY
BEING SOME 20-25 DEGREES COOLER THAN SUNDAY IN MOST LOCATIONS AND
WITH BRISK WEST WINDS...WIND CHILLS WILL STAY OR FALL INTO THE 20S
AND 30S. CLEARING SHOULD SPREAD ACROSS THE AREA EARLY MONDAY. HIGH
PRESSURE CENTERS OVER ILLINOIS ON TUESDAY AND TUESDAY MORNING
SHOULD HAVE GOOD RADIATION AL COOLING CONDITIONS WITH A HARD FREEZE
LIKELY FOR MOST OF CENTRAL AND SOUTHEAST ILLINOIS.
850 MB TEMPS SLOWLY REBOUND AS THE AIR MASS MODERATES AFTER
TUESDAY AND TEMPS SHOULD REACH CLOSE TO NORMAL FOR THE LATER PART
OF THE WEEK.
MODEL SPREAD INCREASES SIGNIFICANTLY IN THE NAEFS AND OPERATIONAL
MODELS FOR THE LATER HALF OF THE WEEK WITH GENERALLY WEAK FLOW AND
ABOVE NORMAL HEIGHTS. MOST LIKELY SCENARIO SUGGESTS HIGH PRESSURE
RIDGING INTO IL FROM THE NORTHEAST KEEPING DRY WEATHER IN PLACE
INTO THE WEEKEND.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 8 PM CST THIS EVENING FOR ILZ027>031-036>038-
040>057-061>063-066>068-071>073.
&&
$$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
336 PM CST SUN NOV 11 2012
.SHORT TERM /TONIGHT/...
EXTRAPOLATION AND RAP FORCING SUGGEST PRECIP WILL COME TO AN END IN
OUR FORECAST AREA BY 00Z SO NOTHING BEYOND LINGERING LIGHT
RAIN...LIGHT SLEET OR LIGHT SNOW FAR SE LATE THIS AFTERNOON AS COLD
AIR CONTINUES TO DEEPEN. HAVE HAD NO REPORTS OF ANYTHING BEYOND
TOKEN PERIODS OF LIGHT SLEET AS OF YET HOWEVER. CERTAINLY NO
ACCUMULATIONS.
SKIES SHOULD CLEAR THIS EVENING LEADING TO MIN TEMP CONCERNS.
ALTHOUGH MOS SHOWS LOWS IN THE MID TEENS AND LOWER 20S...FORECAST
SOUNDINGS SUGGEST AIRMASS WILL REMAIN MIXED THROUGH THE NIGHT WITH
PERSISTENT NW WINDS. THIS SEEMS REASONABLE SO HAVE BLENDED MOS AND
SOMEWHAT WARMER RAW MODEL TEMPS FOR LOWS.
.LONG TERM /MONDAY THROUGH /...
FEW CONCERNS WITH EXTENDED AS STRONG LOW PRESSURE SYSTEM
CONTINUES TO PUSH NE. BEHIND LOW...UPPER LEVEL FLOW WILL BE MOSTLY
ZONAL. TEMPERATURES WILL REMAIN COLD FOR MONDAY AND MONDAY NIGHT
AS COLD CANADIAN AIR REMAINS IN PLACE BEHIND STRONG COLD
FRONT...WITH LITTLE WARMING FOR MONDAY. HAVE LEFT MENTION OF
ISOLATED FLURRIES ACROSS THE NORTH MONDAY WITH WRAP AROUND OF LOW
CROSSING INTO MN. HAVE DROPPED OVERNIGHT LOWS MONDAY NIGHT AS
SKIES CLEAR AND WINDS BECOME LIGHT EXPECT GOOD RADIATIONAL
COOLING. WILL BE WAA INCREASING ACROSS THE WEST MONDAY NIGHT...BUT
WITH 850 TEMPS STILL BELOW 0C...EXPECT TEMPS TO DROP INTO THE
TEENS AND 20S. A WEAK WAVE WILL PUSH THROUGH FOR WEDNESDAY...WITH
SOUTHERLY FLOW INCREASING. WAVE WILL BRING LITTLE IMPACT WITH LACK
OF MOISTURE. TEMPERATURES WILL CONTINUE TO WARM WITH SOUTHERLY
FLOW THROUGH THE WEEK...AND WILL SEE A RETURN TO SLIGHTLY ABOVE
NORMAL TEMPERATURES FOR THE END OF THE WORK WEEK.
NEXT SYSTEM OF CONCERN REMAINS LOW PRESSURE SYSTEM DEVELOPING
ACROSS WESTERN PLAINS FOR END OF THE PERIOD. MODELS CONTINUE TO
WEAKEN AND SLOW THIS SYSTEM. HAVE CUT BACK ON POPS FOR THE
WEEKEND...KEEPING THEM CONFINED TO THE WEST AND SW FOR SATURDAY
AND SUNDAY. MODELS DO NOT HAVE GOOD AGREEMENT ON TRACK OR
PLACEMENT OF THE LOW HOWEVER...SO THIS COULD CONTINUE TO CHANCE.
STILL LOOKS LIKE BEST CHANCES FOR PRECIPITATION WILL BE BEYOND THE
FORECAST PERIOD NEXT WEEK AS LOW PUSHES EAST.
&&
.AVIATION...11/18Z
WIDESPREAD MVFR/IFR CONDITIONS PERSIST OVER FORECAST AREA WITH MUCH
OF PRECIP NOW ALONG OR JUST EAST OF KMCW-KDSM-KLWD LINE. EXPECT
PRECIP TO CONTINUE ADVANCING EASTWARD AND NOT ENDING AT KOTM UNTIL
AROUND 00Z...AND AT LEAST MVFR CIGS LINGERING FOR SEVERAL HOURS
AFTER THAT. SKIES SHOULD THEN BECOME VFR/MOSTLY CLEAR OVERNIGHT.
SUSTAINED WINDS WILL NOT DIMINISH TOO MUCH OVERNIGHT AND THEN BECOME
GUSTY AGAIN DURING MIXING LATE MON MORNING.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...SMALL
LONG TERM...AWB
AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
345 PM MST SUN NOV 11 2012
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 115 PM MST SUN NOV 11 2012
LATEST WV IMAGERY AND RUC H5 ANALYSIS SHOW LARGE POSITIVELY TILTED
TROUGH OVER THE CENTRAL US WITH ITS AXIS EXTENDING SOUTH ALONG THE
KS/CO STATE LINE AND OVER THE TX/OK PANHANDLES. AT THE SURFACE A
COLD FRONT HAS PUSHED WELL SOUTH AND EAST OF THE CWA...NOW EXTENDING
FROM NORTHERN TX AND THEN BACK TO THE NE ACROSS THE CENTRAL
MISSISSIPPI RIVER VALLEY.
LIGHT SNOW ASSOCIATED WITH H7 FRONTOGENETICAL FORCING HAS ALL BUT
ENDED WITH ONLY A FEW LINGERING FLURRIES OVER OUR SW CWA. THIS
ACTIVITY SHOULD CONTINUE TO DIMINISH THIS AFTERNOON AS SUBSIDENCE AND
A STABLE AIRMASS CONTINUES TO MOVE IN FROM WYOMING AND THE NEBRASKA
PANHANDLE WHERE CLEARING IS ALREADY OBSERVED ON SATELLITE.
WHILE THERE WILL BE A SLIGHT MODERATION OF THE AIRMASS OVER THE CWA
OVERNIGHT WE WILL STILL SEE H85 TEMPS IN THE -4C TO -1C RANGE.
CONSIDERING HOW COLD MANY LOCATIONS GOT EARLY THIS MORNING WITH ONLY
A FEW BREAKS IN CLOUD COVER AND WINDS IN THE 10 TO 20 MPH...TONIGHT
WILL ACTUALLY BE MUCH BETTER FOR COOLING WITH CLEARING SKIES AND
RELATIVELY LIGHT WINDS. RIGHT NOW I HAVE TEMPS RANGING FROM 10 TO
18F ACROSS THE CWA TONIGHT...HOWEVER I WOULD NOT BE SURPRISED IF WE
SEE TEMPERATURES A FEW DEGREES COOLER THAN THIS.
THE AIR MASS WILL CONTINUE TO MODERATE MONDAY WITH HIGH TEMPERATURES
RECOVERING TO THE UPPER 40S/LOW 50S. A VERY DRY AIRMASS WILL REMAIN
IN PLACE WHICH WILL RESULT IN RH VALUES WITHIN RED FLAG CRITERIA.
WINDS APPEAR TO BE MARGINAL SO NO RFW IS PLANNED...HOWEVER THIS MAY
NEED TO BE WATCHED IN THE EVENT THAT WINDS ARE A LITTLE STRONGER.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 115 PM MST SUN NOV 11 2012
MONDAY NIGHT-WEDNESDAY...ONE UPPER DISTURBANCE MOVES ACROSS THE AREA
TUESDAY WITH NOTHING BUT AN INCREASE IN CLOUDINESS. ANOTHER BATCH OF
CLOUDS MOVE IN WEDNESDAY AFTERNOON AND CONTINUE THROUGH THE NIGHT AS
ANOTHER SYSTEM MOVES THROUGH THE NORTHERN AND CENTRAL PLAINS.
SEASONAL HIGH TEMPERATURES WITH BELOW NORMAL TEMPERATURES MONDAY
NIGHT AND TUESDAY NIGHT...NEAR TO SLIGHTLY ABOVE NORMAL WEDNESDAY
NIGHT.
THURSDAY-SUNDAY...NOT MUCH GOING ON TIL FRIDAY NIGHT THROUGH
SATURDAY NIGHT WHEN A WEATHER SYSTEM MOVES ACROSS THE AREA. NOT MUCH
IN THE WAY OF PRECIPITATION HOWEVER. OTHERWISE SEASONAL TEMPERATURES
FOR THIS TIME OF YEAR.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 345 PM MST SUN NOV 11 2012
VFR THROUGH THE PERIOD AT KGLD AND KMCK. VRB WINDS AT BEGINNING OF
TAF PERIOD WILL BECOME WESTERLY AT 9-12KTS BY 06Z THEN SHIFT TO
THE W/NW AT 10-15KTS BY 17Z MONDAY AS A WEAK UPPER WAVE AND
ASSOCIATED MID AND HIGH LEVEL CLOUDS MOVE THROUGH. BY 23Z WINDS
WILL BECOME VARIABLE AT 5KTS OR LESS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...99
AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
115 PM MST SUN NOV 11 2012
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 115 PM MST SUN NOV 11 2012
LATEST WV IMAGERY AND RUC H5 ANALYSIS SHOW LARGE POSITIVELY TILTED
TROUGH OVER THE CENTRAL US WITH ITS AXIS EXTENDING SOUTH ALONG THE
KS/CO STATE LINE AND OVER THE TX/OK PANHANDLES. AT THE SURFACE A
COLD FRONT HAS PUSHED WELL SOUTH AND EAST OF THE CWA...NOW EXTENDING
FROM NORTHERN TX AND THEN BACK TO THE NE ACROSS THE CENTRAL
MISSISSIPPI RIVER VALLEY.
LIGHT SNOW ASSOCIATED WITH H7 FRONTOGENETICAL FORCING HAS ALL BUT
ENDED WITH ONLY A FEW LINGERING FLURRIES OVER OUR SW CWA. THIS
ACTIVITY SHOULD CONTINUE TO DIMINISH THIS AFTERNOON AS SUBSIDENCE AND
A STABLE AIRMASS CONTINUES TO MOVE IN FROM WYOMING AND THE NEBRASKA
PANHANDLE WHERE CLEARING IS ALREADY OBSERVED ON SATELLITE.
WHILE THERE WILL BE A SLIGHT MODERATION OF THE AIRMASS OVER THE CWA
OVERNIGHT WE WILL STILL SEE H85 TEMPS IN THE -4C TO -1C RANGE.
CONSIDERING HOW COLD MANY LOCATIONS GOT EARLY THIS MORNING WITH ONLY
A FEW BREAKS IN CLOUD COVER AND WINDS IN THE 10 TO 20 MPH...TONIGHT
WILL ACTUALLY BE MUCH BETTER FOR COOLING WITH CLEARING SKIES AND
RELATIVELY LIGHT WINDS. RIGHT NOW I HAVE TEMPS RANGING FROM 10 TO
18F ACROSS THE CWA TONIGHT...HOWEVER I WOULD NOT BE SURPRISED IF WE
SEE TEMPERATURES A FEW DEGREES COOLER THAN THIS.
THE AIR MASS WILL CONTINUE TO MODERATE MONDAY WITH HIGH TEMPERATURES
RECOVERING TO THE UPPER 40S/LOW 50S. A VERY DRY AIRMASS WILL REMAIN
IN PLACE WHICH WILL RESULT IN RH VALUES WITHIN RED FLAG CRITERIA.
WINDS APPEAR TO BE MARGINAL SO NO RFW IS PLANNED...HOWEVER THIS MAY
NEED TO BE WATCHED IN THE EVENT THAT WINDS ARE A LITTLE STRONGER.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 115 PM MST SUN NOV 11 2012
MONDAY NIGHT-WEDNESDAY...ONE UPPER DISTURBANCE MOVES ACROSS THE AREA
TUESDAY WITH NOTHING BUT AN INCREASE IN CLOUDINESS. ANOTHER BATCH OF
CLOUDS MOVE IN WEDNESDAY AFTERNOON AND CONTINUE THROUGH THE NIGHT AS
ANOTHER SYSTEM MOVES THROUGH THE NORTHERN AND CENTRAL PLAINS.
SEASONAL HIGH TEMPERATURES WITH BELOW NORMAL TEMPERATURES MONDAY
NIGHT AND TUESDAY NIGHT...NEAR TO SLIGHTLY ABOVE NORMAL WEDNESDAY
NIGHT.
THURSDAY-SUNDAY...NOT MUCH GOING ON TIL FRIDAY NIGHT THROUGH
SATURDAY NIGHT WHEN A WEATHER SYSTEM MOVES ACROSS THE AREA. NOT MUCH
IN THE WAY OF PRECIPITATION HOWEVER. OTHERWISE SEASONAL TEMPERATURES
FOR THIS TIME OF YEAR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1048 AM MST SUN NOV 11 2012
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD AT BOTH GLD AND
MCK. NORTHWEST FLOW ALOFT TODAY AS DEEP UPPER LEVEL TROUGH EXITS THE
CENTRAL PLAINS. A FEW HIGH CLOUDS THIS AFTERNOON WITH LIGHT WINDS
OUT OF THE NORTH-NORTHWEST...THOUGH A FEW GUSTS TO 20KTS CANNOT BE
RULED OUT. OVERNIGHT WINDS GRADUALLY BACK TO THE WEST AT
6-8KTS...AND SKIES WILL BE MOSTLY CLEAR WITH A FEW MID LEVEL CLOUDS
POSSIBLE BY SUNRISE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...99
AVIATION...JJM/DR
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
445 PM EST SUN NOV 11 2012
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 442 PM EST SUN NOV 11 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A DEEP TROF EXTENDING FROM
SCNTRL CANADA THRU THE WRN PLAINS. DEEP SRLY FLOW THAT HAS BEEN
OCCURRING AHEAD OF THE TROF HAS TRANSPORTED ABUNDANT MOISTURE N INTO
THE WRN GREAT LAKES. 12Z RAOBS SHOW PRECIPITABLE WATER RUNNING
200-275PCT OF NORMAL OVER THE WRN GREAT LAKES. AT THE SFC...SHARP
COLD FRONT EXTENDS FROM CNTRL LAKE SUPERIOR TO JUST E OF THE
KEWEENAW AND THEN S TO THE W OF KIMT. SHARP FRONT PLOWING INTO DEEP
MOISTURE COMBINED WITH HEALTHY UPPER DIVERGENCE ASSOCIATED WITH
130-140KT UPPER JET STREAK LIFTING UP FRONT SIDE OF TROF HAS
RESULTED IN A SOLID BAND OF SHRA ALONG THE COLD FRONT TODAY. BEHIND
THE FRONT...TEMP HAS ALREADY PLUMMETED TO 37 AT KIWD WHERE RAIN IS
JUST ABOUT DONE.
THERE ARE PLENTY OF CONCERNS IN THE SHORT TERM...RANGING FROM
PROGRESSION OF RAIN BAND E ACROSS THE AREA TONIGHT...POSSIBLE BRIEF
WINTRY MIX ON THE BACKSIDE OF THE RAIN...AND THEN TRANSITION TO LES
AND POSSIBLE WINTER WX HEADLINE MON.
FCST FOR THIS EVENING IS LARGELY BASED ON EXTRAPOLATION OF SHRA.
SINCE UPPER DIVERGENCE OVERTOP SHARP COLD FRONT WILL ALLOW SHRA TO
PERSIST ALONG FRONT AS IT MOVES E...WILL SPREAD CATEGORICAL POPS
STEADILY E ACROSS THE CNTRL AND ERN FCST AREA TONIGHT IN ASSOCIATION
WITH SFC COLD FRONT WHICH SHOULD REACH THE SOO LATE TONIGHT. PCPN
ACROSS THE W AND CNTRL WILL END AS RIBBON OF PRONOUNCED MIDLEVEL
DRYING FOLLOWS UPPER JET STREAK TRANSLATING ACROSS THE AREA. BEFORE
PCPN ENDS...THERE IS A SMALL WINDOW FOR A LITTLE SLEET THEN SNOW TO
OCCUR AS INITIALLY SHALLOW COLD AIR UNDERCUTS THE LINGERING WARMER
AIR ALOFT. HOWEVER...THERE ISN`T MUCH SIGNAL FOR SUFFICIENT FORCING
TOO FAR W OF THE COLD FRONT TO COUNTER THE SHARP MID LEVEL DRYING
AND KEEP PCPN LINGERING IN THE COLD AIR FOR TOO LONG. ANY SLEET OR
SNOW THAT DOES OCCUR ON THE BACKSIDE OF THE MAIN FRONTAL SHRA BAND
SHOULDN`T AMOUNT TO MUCH IF ANYTHING. THE MIXED PCPN POTENTIAL WILL
SPREAD INTO THE ERN FCST AREA LATE TONIGHT AS MODELS ARE A LITTLE
FASTER WITH CAA. LINGERING LIGHT PCPN OVER THE E SHOULD END BY MID
MORNING MON.
AS MAIN SYNOPTIC PCPN EXITS...ATTENTION TURNS TO LAKE EFFECT SNOW.
WITH SFC WATER TEMPS OVER WRN LAKE SUPERIOR AROUND 6C...MODEL
CONSENSUS IS FOR 850MB TEMPS TO FALL SUFFICIENTLY FOR LES
DEVELOPMENT AFTER 06Z...BUT MORE SO BTWN 09-12Z AS TEMPS WILL BE
DOWN TO -12 TO -14C AT 12Z. MIDLEVEL DRY SLOT WILL INITIALLY WORK TO
KEEP COVERAGE MORE LIMITED. SO SCT COVERAGE POPS FOR -SHSN APPEAR ON
TRACK FOR THE OVERNIGHT.
LES FCST GETS MORE INTERESTING MON AS MID LEVEL TROF AXIS AND POOL
OF DEEP MOISTURE ARRIVES. THIS RESULTS IN INVERSION LIFTING TOWARD
10KFT. WITH 850MB TEMPS AVERAGING AROUND -13C THRU THE DAY...DGZ
ENDS UP WITHIN THE MOIST CONVECTIVE LAYER...AND AT LEAST WITH THE
NAM...THERE IS A NICE INTERSECTION OF UPWARD MOTION THRU THE DGZ.
WIND DIRECTION WILL BE CRITICAL. VARIOUS HIGH RES MODELS (LOCAL HIGH
RES WRF AND NCEP HIGH RES ARW/NMM) INCLUDING NAM/REGIONAL GEM ARE IN
GOOD AGREEMENT SHOWING MORE OF A WSW WIND OVER WRN LAKE SUPERIOR AND
ARE SUGGESTIVE OF A DOMINANT CONVERGENT BAND DEVELOPING NEAR THE
APOSTLE ISLANDS AND STREAMING TOWARD THE NRN PORTION OF THE KEWEENAW
PENINSULA MON...WHICH IS A COMMON OCCURRENCE FOR THIS TYPE OF
LOW-LEVEL WIND FLOW. GIVEN THE AGREEMENT...HAVE FOLLOWED THIS
SCENARIO. WITH POTENTIAL OF MDT TO PERHAPS HVY LAKE ENHANCED SNOW AT
TIMES GIVEN FAVORABLE TEMP/MOISTURE PROFILE...OPTED TO GO WITH A
WINTER WX ADVY FOR NRN HOUGHTON/KEWEENAW COUNTIES MON. EXPECT MAIN
FOCUS OF HEAVIER LES TO BE N OF HOUGHTON...PARTICULARLY IN THE AFTN
OVER THE HIGHER TERRAIN FROM AROUND CALUMET THRU DELAWARE WHERE SNOW
MAY ACCUMULATE TO AROUND 4 INCHES DURING THE DAY MON. VERY LATE IN THE
AFTN...WINDS WILL BEGIN TO SHIFT MORE TO THE W WHICH WILL PUSH
HEAVIER SNOW OVER MORE OF THE KEWEENAW PENINSULA. SINCE ONTONAGON
COUNTY WILL BE SOUTH OF THE HEAVIER SNOW AND POSSIBLY S OF MOST OF
THE LAKE ENHANCED SNOW...DID NOT INCLUDE ADVY FOR THAT AREA AT THIS
TIME. TO THE E...WINDS WILL PROBABLY HAVE ENOUGH OFFSHORE COMPONENT
TO KEEP MOST OF THE DEVELOPING LAKE ENHANCED SNOW OFFSHORE OF
ALGER/LUCE COUNTIES. ELSEWHERE...EXPECT SCT FLURRIES/-SHSN TO
ACCOMPANY ARRIVAL OF MIDLEVEL TROF OVER ROUGHLY THE W HALF OF UPPER
MI MON. WITH 850MB THERMAL TROF MOVING OVER THE AREA...TEMPS SHOULD
RISE VERY LITTLE. IN FACT...TO THE W...TEMPS THIS AFTN ARE ONLY IN
THE UPPER TEENS/LWR 20S IN THE ERN DAKOTAS/WRN MN. SO...TEMPS LIKELY
WON`T RISE OUT OF THE MID/UPPER 20S OVER WRN UPPER MI MON...AND
TEMPS MAY FALL SOME OVER THE E AS CAA CONTINUES THRU THE MORNING IN
THAT AREA.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 442 PM EST SUN NOV 11 2012
NOT MUCH CHANGE TO PREVIOUS FORECAST THINKING IN THE LONG TERM WITH
MAIN FOCUS MON NIGHT INTO TUE WITH LES.
A SHARP UPPER TROUGH WILL BE OVER THE CENTRAL CWA /E OF THE
KEWEENAW/ AT 00Z TUE WITH A SLIGHTLY LAGGING SFC TROUGH OVER WRN
LAKE SUPERIOR. COLD AIR ASSOCIATED WITH THIS TROUGH CAUSES CONCERN
WITH CHANCES FOR LES PARTICULARLY OVER THE KEWEENAW PENINSULA. 850MB
TEMPS WILL BE AROUND -11C AT 00Z TUE...WITH THE TOP OF THE INVERSION
ABOVE THE DGZ AT AROUND 9500FT WITH TEMPS AROUND -24C. WHILE 850MB
TEMPS WILL BE A COUPLE OF DEGREES WARMER THAT A FEW HOURS
BEFORE...THE INVERSION LOOKS TO BE DEEPEST AROUND 00Z TUE...SO BEST
OVERALL AVG COVERAGE/INTENSITY SHOULD BE SEEN AROUND THIS TIME.
AFTER 00Z TUE...A SFC RIDGE WILL MOVE OVERHEAD BY 18Z TUE WITH 850MB
TEMPS STEADILY INCREASING TO AOA -5C BY 00Z WED. MOISTURE...WHICH
WILL BE AMPLE FOR LES AT 00Z...WILL DECREASE AFTER 00Z TUE. MOISTURE
FROM 850MB AND UP WILL DECREASE TO BELOW 60 PERCENT RH OVER THE WRN
HALF OF LAKE SUPERIOR BY 09Z TUE...AND OVER THE ENTIRE LAKE BY 15Z
TUE. 925MB-850MB RH DECREASES BELOW 60 PERCENT OVER THE WRN HALF OF
LAKE SUPERIOR BY 15Z TUE...AND THE MOST OF THE REST OF THE LAKE BY
00Z WED. AT LEAST FROM 00Z TUE TO 06Z WED...WINDS LOOK TO GUST TO
35-40MPH OVER THE KEWEENAW PENINSULA WITH THE W WINDS. COLD SECTOR
LIVING AT ITS BEST.
TAKING A CLOSER LOOKS AT SNOWFALL AMOUNTS AND OTHER HAZARDS FOR TUE
NIGHT...LOW LEVEL WINDS WILL BE FAIRLY UNIDIRECTIONAL...WHICH IS
GOOD FOR LES BANDING. HOWEVER...WINDS WILL BE SHIFTING FROM A WSW
DIRECTION MON EVENING...WHICH WILL FAVOR A DOMINANT BAND WITH
INTENSE SNOWFALL AMOUNTS LATE MON. THOSE WSW WINDS BECOME MORE WLY
BY 00Z TUE AND SLOWLY VEER INTO TUE AS THE RIDGE MOVES IN FROM THE
W. THIS WILL MOVE THE WEAKENING DOMINANT BAND FROM N TO S ACROSS THE
KEWEENAW AND INTO ONTONAGON COUNTY MON NIGHT...BUT THE FACT THAT
WINDS WILL STEADILY VEER WILL KEEP THE STRONGER BAND FROM SITTING
OVER ANY ONE PLACE FOR TOO LONG...HELPING TO KEEP SNOWFALL TOTALS
FROM GETTING TO HIGH. THE BEST AREA OF LIFT WILL SPAN THE
DGZ...WHICH WILL HELP MAKE SNOW TO LIQUID RATIOS HIGH...BUT GUSTY
WINDS WILL KNOCK THOSE DOWN SOME. EXPECT SLR VALUES AROUND 18-20 TO
1. ADDITIONAL SNOWFALL AMOUNTS MON NIGHT /ON TOP OF WHAT FALL MON/
LOOK TO BE UP TO AROUND 4 INCHES...HIGHEST OVER THE HIGHER TERRAIN
FROM ROCKLAND TO SOUTH RANGE. WITH THE WINDS...BLOWING SNOW WILL
ALSO BE AN ISSUE...BUT A LIMITED ONE GIVEN NO SNOW ON THE GROUND
YET. AS FOR THE TUE MORNING COMMUTE OVER THE KEWEENAW...BY 12Z TUE
WINDS WILL HAVE DIMINISHED TO 20MPH OR LESS AND SNOWFALL RATES
SHOULD BE GREATLY REDUCED...SO CONDITIONS WILL MAINLY DEPEND ON HOW
WELL ROAD CREWS CAN CLEAR EARLIER SNOW OFF THE ROADS...BUT AT LEAST
SLICK ROADS APPEAR LIKELY.
WITH THE WINDS BECOMING MORE WNW THROUGH THE NIGHT...THE ERN CWA
NEAR LAKE SUPERIOR /MAINLY E OF MUNISING/ SHOULD SEE SOME MODERATE
TO HEAVY SNOWFALL AS WELL. THE FORECAST IS A BIT TRICKIER OVER
THERE...MAINLY DUE TO UNCERTAINTY WITH WHEN AND HOW FAR LES BAND
WILL MOVE ONSHORE. SIMILAR TO THE KEWEENAW THERE SHOULD BE A MORE
DOMINANT BAND SITTING OVER ERN LAKE SUPERIOR THAT WILL PUSH ONSHORE
AS CONDITIONS START TO BECOME LESS FAVORABLE FOR LES. PUSH
CONDITIONS BACK A FEW HOURS FROM TIMING OVER THE KEWEENAW...SO THE
BAND SHOULD BEGIN TO VEER ONSHORE AROUND 06Z TUE...BUT SHOULD BEGIN
WEAKENING SHORTLY DUE TO DRIER AIR AND MORE ANTICYCLONIC FLOW
GRADUALLY MOVING IN. COULD SEE TOTAL SNOWFALL AMOUNTS OF 3-4 INCHES
MON NIGHT INTO TUE.
HAVE A WINTER WX ADV THAT EXTENDS TO 12Z TUE FOR NRN HOUGHTON AND
KEWEENAW COUNTIES. WILL POSSIBLY NEED AN ADV FOR ONTONAGON AND MAYBE
SOUTHERN HOUGHTON COUNTY MON NIGHT...BUT WILL LEAVE THOSE DETAILS TO
MIDNIGHT SHIFT AND HIGHLIGHT IN HWO. ALSO MAY NEED AN ADV FOR PARTS
OF THE ERN CWA CLOSE TO LAKE SUPERIOR...BUT THOSE DETAILS ARE EVEN
LESS CERTAIN.
WITH FAIRLY BENIGN...LOW IMPACT WEATHER AFTER CONDITIONS SUBSIDE
TUE...JUST USED A CONSENSUS OF THE MODELS FOR THE REST OF THE
FORECAST SO AS TO PLACE MOST TIME/EMPHASIS ON SHORTER TERM IMPACTS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1256 PM EST SUN NOV 11 2012
CONDITIONS WILL CONTINUE TO DETERIORATE AS SHRA OVERSPREADS WESTERN
AND CENTRAL UPPER MI IN RELATION TO A DISTURBANCE RIDING NEWD ALONG
COLD FRONT...CURRENTLY OVER FAR WESTERN UPPER MI. KEPT TAF SITES
WITHIN FUEL ALTERNATE CATEGORIES THROUGH THIS EVENING...THOUGH AS
MENTIONED BY PREVIOUS FORECAST...LIFR CONDITIONS CAN NOT BE RULED
OUT AT SOME POINT...ESPECIALLY AT CMX THIS AFTN/EVNG WITH GUSTY
UPSLOPE W WIND BEHIND THE COLD FROPA. EXPECT THE ARRIVAL OF DRIER
AIR TO CAUSE THE PCPN TO DIMINISH JUST AS ENUF COLD AIR SURGES INTO
THE AREA TO CHANGE THE RA TO SN. THE BEST CHC FOR HEAVIER -SHSN
LATER TNGT WL BE AT THE MORE EXPOSED CMX LOCATION...WHERE GUSTY
WINDS WL LINGER AS WELL. OTHERWISE...DRY AIR WILL CONTINUE TO
IMPROVE CIG CONDITIONS TO VFR AT KIWD AND KSAW BY MONDAY MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 442 PM EST SUN NOV 11 2012
SHARP COLD FRONT IS IN THE PROCESS OF CROSSING LAKE SUPERIOR ATTM.
AHEAD OF THE FRONT...S WINDS OVER ERN LAKE SUPERIOR WILL GUST TO
GALE FORCE AT TIMES THIS EVENING...ESPECIALLY IN THE AREA AROUND
GRAND MARAIS WHICH IS FAVORED FOR STRONG WINDS IN SOUTHERLY FLOW.
ALTHOUGH CAA IS STRONG BEHIND COLD FRONT...LACK OF STRONGER SFC PRES
RISES WILL PROBABLY RESULT IN WESTERLY WINDS REMAINING BLO GALE
FORCE TONIGHT. PRESSURE GRADIENT TIGHTENS JUST A BIT ON MON AS
SECONDARY SFC TROF APPROACHES. WITH COLD AIR AND UNSTABLE
LOW-LEVELS...OCNL GALE FORCE GUSTS TO 35KT ARE POSSIBLE MON/MON
EVENING. PRESSURE GRADIENT THEN SLACKENS LATE MON NIGHT/TUE WITH
WINDS DIMINISHING BLO 25 KTS. A LOW PRES TROF WILL PUSH ACROSS
NORTHERN ONTARIO THU. S WINDS AHEAD OF THE TROF COULD REACH 25 KTS
OVER EASTERN SECTIONS OF LAKE SUPERIOR WED/WED NIGHT. WINDS TO
FINISH UP THE WEEK WILL BE BLO 20 KTS AS PRESSURE GRADIENT BECOMES
WEAK WITH SFC HIGH PRES PASSING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY FROM 7 AM MONDAY TO 7 AM EST TUESDAY FOR
MIZ001-003.
LAKE SUPERIOR...NONE.
LAKE MICHIGAN...
GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LMZ248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...JMW
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1258 PM EST SUN NOV 11 2012
LATEST UPDATE...AVIATION...
.SYNOPSIS...
ISSUED AT 328 AM EST SUN NOV 11 2012
STRONG SOUTH WINDS WILL DEVELOP ACROSS THE REGION TODAY AHEAD OF A
STRONG COLD FRONT. A PUSH OF WARM AIR WILL SEND TEMPERATURES INTO
THE UPPER 60S A MANY LOCATIONS THIS AFTERNOON. SHOWERS WILL DEVELOP
LATE IN THE DAY AND CONTINUE TONIGHT AS THE FRONT MOVES ACROSS THE
AREA. MUCH COLDER AIR ALONG WITH RAIN AND SNOW SHOWERS WILL MOVE
INTO WEST MICHIGAN MONDAY. HIGH TEMPERATURES WILL SLOWLY FALL DURING
THE DAY AND ONLY REACH AROUND 40 DEGREES TUESDAY. MAINLY DRY WEATHER
IS EXPECTED AFTER MONDAY WITH SLOWLY WARMING TEMPERATURES.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EST SUN NOV 11 2012
FORECAST CONCERNS DEAL WITH THE WIND POTENTIAL TODAY AND PCPN TRENDS
TONIGHT/MONDAY.
THE GOING FORECAST IS LARGELY ON TRACK. HOWEVER...WINDS APPEAR A BIT
STRONGER ACROSS THE WRN CWA AS THE GRADIENT TIGHTENS AHEAD OF THE
COLD FRONT. AS SUCH WE ISSUED A WIND ADVISORY FOR THE WRN 1/2 OF THE
CWA. WINDS ARE ALREADY GUSTING TO 36 KITS AT KMKG AND WILL LIKELY
INCREASE A BIT MORE AS THE SUN RISES AND BETTER MIXING OCCURS.
STRONG 65KT LLJ MOVES OVER THE WRN CWA LATE THIS AFTERNOON.
LATEST HRRR HAS A PRETTY GOOD HANDLE ON THE SHOWERS MOVING ACROSS
NRN IL/WISCONSIN. THESE ARE AHEAD OF THE COLD FRONT AND DISSIPATE
SOMEWHAT AS THEY MOVE EWD THIS AFTERNOON. AS A RESULT...WE
ANTICIPATE A DRY DAY. ABUNDANT MID CLOUD WILL BE PRESENT AND THIS
WILL LIMIT MIXING A BIT BUT NOT ENOUGH TO PREVENT SUSTAINED 25 TO 30
MPH WINDS. FROPA IS ON TRACK FOR MIDNIGHT-4AM TIME FRAME. TEMPS WILL
SLOWLY FALL MONDAY AS H8 TEMPS FALL TO -12C. RAIN WILL MIX WITH SNOW
AFTER FROPA THEN BECOME SHSN AS THE THERMAL PROFILE QUICKLY FALLS
BELOW 0C. NOT LOOKING FOR ACCUMS AT THIS POINT. THOUGH IT/S POSSIBLE
A FEW HIGHER ELEVATIONS ACROSS THE NRN CWA COULD SEE A COUPLE OF
TENTHS.
TUESDAY LOOKS DRY BUT CHILLY WITH HIGHS AROUND 40.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EST SUN NOV 11 2012
FOR THE EXTENDED PERIOD...THE CORE OF THE ARCTIC AIR REMAINS WELL
NORTH OF THE REGION. ONE OF THE MAIN REASONS FOR THIS IS THE ZONAL
MID LEVEL FLOW THAT SETS UP ACROSS NORTH AMERICA FOR THE PERIOD.
HERE IN MI...WE WILL SEE ONLY A WEAKENING COLD FRONT ARRIVING THU.
IF THERE IS ANY PRECIPITATION WITH THIS SHALLOW FEATURE...IT WILL BE
LIMITED AS VERY LITTLE MOISTURE AND LIFT WILL BE IN PLACE.
TEMPERATURES AT 850 MB CLIMB THU INTO SAT...SO WE WILL LIKELY SEE A
GENERAL WARMING TREND. ALTHOUGH...GIVEN THE MID LEVEL
FLOW...PACIFIC MOISTURE COULD CAUSE PERIODS OF CLOUDS THAT WOULD
POTENTIALLY LIMIT THE DAYTIME MIXING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY)
ISSUED AT 1258 PM EST SUN NOV 11 2012
STRONG SOUTH FLOW AHEAD OF A COLD FRONT WILL RESULT IN GUSTS OVER 25
KNOTS FOR ALL TAF SITES INTO THE EVENING. WINDS WILL DECREASE A BIT
OVERNIGHT... BUT WILL PICK UP OUT OF THE WEST BEHIND THE FRONT.
EXPECTING CEILINGS TO FALL TO AROUND 2500 FEET TONIGHT WITH
VISIBILITIES MOSTLY ABOVE 3SM. ISOLATED IFR LEVELS MAY BE
EXPERIENCED UNDER THE STRONGEST CELLS. FEEL LOW CHANCE AT TAF SITES
FOR IFR OVERNIGHT... SO DID NOT INCLUDE. WENT WITH VCSH FOR MONDAY.
THE TEMPERATURES WILL BE FALLING... SO RAIN SHOWERS WILL TRANSITION
TO SNOW SHOWERS.
&&
.MARINE...
ISSUED AT 328 AM EST SUN NOV 11 2012
GIVEN THAT WINDS ALONG THE LAKESHORE ARE ALREADY GUSTING NEAR
35KTS...DECIDED TO RUN WITH THE GALE WARNING NOW AND DISCONTINUE THE
SCA. GALES TO 40KTS EXPECTED TODAY WILL BUILD WAVES TO 5 TO 8 FEET.
&&
.HYDROLOGY...
ISSUED AT 328 AM EST SUN NOV 11 2012
A THIRD OF AN INCH OF PCPN IS EXPECTED AHEAD OF THE COLD FRONT
TONIGHT. THIS SHOULDN/T RESULT IN FLOODING.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WIND ADVISORY UNTIL 3 AM EST MONDAY FOR MIZ037-038-043-044-050-
056-057-064-065-071-072.
LM...GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LMZ844>849.
&&
$$
SYNOPSIS...93
SHORT TERM...93
LONG TERM...MJS
AVIATION...63
HYDROLOGY...93
MARINE...93
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1257 PM EST SUN NOV 11 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 533 AM EST SUN NOV 11 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP TROF OVER THE
ROCKIES UPSTREAM OF HI AMPLITUDE RDG IN THE E. VIGOROUS SHRTWV WITH
CLOSED LO AT H5 LIFTING NEWD THRU THE NRN PLAINS IS SUPPORTING 995MB
SFC LO PRES OVER NW MN AT 06Z. ATTENDANT SFC WARM FNT LIES W-E ACRS
NCNTRL WI...WITH SHARP TEMP GRADIENT ACRS THIS BNDRY. AT 05Z...SFC
TEMP WAS 51 AT WAUSAU WI TO 64 AT WISCONSIN RAPIDS LESS THAN 50
MILES TO THE S ACRS THE WARM FNT. THE H85 WARM FNT SEPARATING A 00Z
H85 TEMP OF 13C AT MPX FM 2C AT INL STRETCHES W-E ACRS LK SUP.
VIGOROUS WARM/MOIST ADVECTION WITH H7 WINDS AS HI AS 50-70KTS IN A
RIBBON JUST E OF THE ATTENDANT COLD FNT IN THE PLAINS HAS ADVECTED
PWAT OF NEARLY 1 INCH INTO THE UPR LKS...UP TO 250 PCT OF NORMAL.
NMRS SHRA WITH A FEW ELEVATED TS APPEAR TO BE TIED TO H85 WARM FNT
AND ENHANCED BY VIGOROUS UPR DVGC IN ADVANCE OF 130KT H3 JET MAX
LIFTING NEWD THRU THE PLAISN AND STEEPENING LAPSE RATES ACCOMPANYING
THE VIGOROUS WARM/MOIST ADVCTN AT H85-7. THE TS ARE MAINLY OVER WRN
LK SUP...AND THIS AREA OF PCPN IS LIFTING NEWD THRU LK SUP/THE ERN
CWA AT 06Z...BUT SCT -SHRA ARE ALSO PRESENT IN THE H85 WARM SECTOR S
THRU WI. THESE SHRA ARE TENDING TO DIMINISH WITH TIME. LOOKING TO
THE W...THE REMNANTS OF A LINE OF CONVECTION ARE PRESSING EWD THRU
MN AND INTO NW WI WELL AHEAD OF THE ASSOCIATED OCCLUDED/COLD FNT...
BUT LATEST RADAR TRENDS SHOW THIS BAND OF SHRA IS DIMINISHING. THE
THERMAL CONTRAST ACROSS THIS COLD FNT IS EQUALLY IMPRESSIVE... WITH
00Z H85 TEMPS RANGING FM 13C AT MPX AND OMAHA TO -11C AT BISMARCK.
ANOTHER VIGOROUS SHRTWV APPEARS TO BE ROUNDING THE BASE OF THE TROF
IN THE ROCKIES.
FCST CONCERNS DURING THE SHORT TERM ARE MANY AND INCLUDE SHRA/TS
CHCS THRU TNGT AS WELL AS TRANSITION TO MORE WINTRY WX TNGT AS COLD
FNT TO THE W PASSES THRU UPR MI.
TODAY...LATEST MODELS IN FAIRLY GOOD AGREEMENT SHOWING SFC LO IN MN
MOVING TO NEAR PICKLE LAKE ONTARIO BY 00Z MON WITH ATTENDANT COLD
FNT MOVING TO ABOUT MQT-IMT THEN. GUIDANCE REMAINS IN VERY GOOD
SHOWING H3 JET CORE UP TO 130KT LIFTING NNEWD TO NE MN/WRN LK SUP BY
00Z...WITH INCRSG PCPN COVERAGE MAINLY ALONG AND JUST BEHIND THE FNT
WITH ENHANCED UPR DVGC AND BAND OF SHARP FGEN THAT SHOWS UP BEST AT
H8-7 BEING THE MAIN FORCING MECHANISMS TO LIFT VERY MOIST AIRMASS.
GOING FCST POPS SHOWING INCRSG POPS TO CATEGORICAL OVER MUCH OF THE
W AND CENTRAL SEEM ON TRACK AND ARE IN NEED OF ONLY MINOR
ADJUSTMENTS. PCPN OVER THE MORE CAPPED E SHOULD REMAIN MAINLY SCT
-SHRA TO THE E OF THE INCOMING COLD FNT. EXPECT TEMPS TO RISE INTO
THE BALMY 50S FOLLOWING SFC WARM FROPA. ALTHOUGH THE PASSAGE OF THE
COLD FNT WL OPEN THE DOOR TO COLDER AIR TO MOVE INTO THE W HALF AND
FALLING TEMPS AFT WELL ABV NORMAL RELATIVELY EARLY HI TEMPS
ESPECIALLY OVER THE W...THE APRCH OF THE DISTURBANCE SUPPORTS MODEL
FCST THERMAL FIELDS THAT INDICATE THE PCPN WL REMAIN IN THE FORM OF
RA EVEN AT IWD UNTIL ALMOST 00Z.
TONIGHT...UPR DVGC IN RRQ OF 140KT H3 JET MAX/AXIS OF LO-MID LVL
FGEN ASSOCIATED WITH APRCHG SHRTWV WL BRING CATEGORICAL POPS TO
MAINLY THE E HALF OF THE CWA AS SFC FNT PUSHES SLOWLY TO THE
E...REACHING THE SAULT JUST A FEW HRS BEFORE 12Z MON. BULK OF MODELS
SHOW ENUF DRY MID LVL AIR PUSHING EWD TO LIMIT PCPN AMOUNTS OVER THE
W AND THEN CENTRAL WHERE THE AIR WL TURN COLD ENUF TO SUPPORT
SN...BUT H85 TEMPS FALLING TO -10C TO -14C BY 12Z MON OVER THE W WL
BE SUFFICIENTLY COLD TO BRING AT LEAST SCT LK EFFECT SHSN TO AREAS
FAVORED BY FCST W WIND DESPITE SLIGHTLY LLVL ACYC FLOW. ANY SN/SLEET
ACCUM SHOULD BE UNDER AN INCH. SHARP LLVL COOLING ASSOCIATED WITH
H85-7 FGEN MAX SLOPED FAIRLY FAR TO THE W OF THE SFC FNT MAY CREATE
ELEVATED WARM LYR/POTENTIAL FOR SLEET AS WELL AS SN TO THE CNTRL ZNS
ON THE WRN EDGE OF THE LARGER SYNOPTIC SCALE PCPN AREA TO THE E. THE
E SHOULD REMAIN WARM ENUF FOR MAINLY RA GIVEN FCST H85 TEMPS/H100-85
THKNS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 533 AM EST SUN NOV 11 2012
MAIN FOCUS INITIALLY IN LONG TERM IS DEEP/COLD/MOIST LOW-MID LEVEL
TROUGH EXTENDING FROM ONTARIO TO THE MIDDLE MISSISSIPPI RIVER
VALLEY ON MONDAY. SFC COLD FRONT WILL BE THROUGH UPR MICHIGAN BY 12Z
MONDAY. KEPT HIGHER POPS OVER FAR EAST FOR MAINLY SNOW THROUGH MID
MORNING...BUT WILL BE DRYING OUT ELSEWHERE OVER THE EAST IN WAKE OF
THE FRONT.
ALREADY PLENTY COLD ENOUGH AT H85 /H85 TEMPS AROUND -10C/ TO SUPPORT
LK EFFECT OFF LK SUPERIOR TO START THE DAY GIVEN WATER TEMPS AROUND
+8C. OVER-WATER INSTABILITY RAMPS UP FURTHER THROUGH THE DAY WITH
DELTA T/S WELL OVER 20C BY EVENING IN A MOIST ENVIRONMENT TO H7. NOT
THE USUALLY TYPICAL REALLY COLD BUT REALLY DRY AIRMASS FOR THE LK
EFFECT TO WORK ON...AT LEAST NOT UNTIL LATER MONDAY NIGHT WITH
ARRIVAL OF DRIER AIR AOA H85. NAM/GFS SOUNDINGS INDICATE INVERSION
HEIGHTS OR AT LEAST LAKE EQUILIBRIUM LEVELS TOPPING OUT AROUND 10KFT
AND LOW-LEVEL LAPSE RATES EXCEEDING 9C/KM. SINCE IT IS CHILLY AT SFC
AND ALOFT...MUCH OF THE LAKE CONVECTIVE LAYER WILL BE WITHIN HEART
OF DENDRITIC GROWTH ZONE...BOOSTING SLR/S AND ULTIMATELY SNOWFALL
TOTALS.
PRIMARY QUESTION IS HOW QUICKLY ON MONDAY WILL SIGNIFICANT LK EFFECT
SNOW SHOWERS DEVELOP AND WHERE WILL HEAVIER SNOWS OCCUR THROUGH
MONDAY NIGHT. LOW-LEVEL WINDS IN WAKE OF COLD FRONT ARE MORE FROM
WSW INITIALLY ON MONDAY MORNING WHICH FAVORS MAJORITY OF SNOW
IMPACTING MAINLY NORTHERN PORTIONS OF KEWEENAW PENINSULA. SFC WINDS
GRADUALLY TURN MORE NORTHWEST ON MONDAY EVENING AS SFC TROUGH WORKS
ACROSS LK SUPERIOR AND NORTHERN UPR MICHIGAN. SOUNDINGS INDICATE
THAT EVEN AS SUB H85 WINDS ARE MOSTLY FROM THE WSW MUCH OF MONDAY
THE WINDS FROM H8-H7 SHIFT TO NW DURING THE AFTN OVER WESTERN UPR
MICHIGAN. MAY SEE SITUATION WHERE MORE OF A WIDESPREAD SNOW ENVELOPS
MOST OF NW/W UPR MICHIGAN BY MID AFTN DUE TO COOL/MOIST PROFILE
UPWARDS OF H7. MEANWHILE...BLYR WINDS WOULD FAVOR CONVERGENCE BAND
OF HEAVIER SNOW TO SET UP SOMEWHERE ALONG WEST SIDE OF KEWEENAW THEN
GRADUALLY SINKING SOUTHWARD LATE IN THE DAY INTO THE EVENING WITH
THE SFC WIND SHIFT. ALL FACTORS ARE FAVORABLE FOR INTENSE SNOW RATES
AFTN-EVENING WHERE THE BAND DEVELOPS. INSTABILITY PARAMETERS AND
LOCAL GUIDANCE ALONG WITH LAKE SNOW PARAMETER DEVELOPED BY NWS
OFFICE IN GAYLORD MI ALL POINT TO HEAVY SNOWFALL RATES /AT LEAST 1"
PER HR/ LATER MONDAY AFTN AND MONDAY EVENING OVR NW UPR MICHIGAN.
CURRENTLY HAVE POTENTIAL FOR SNOW MENTIONED IN HAZARDOUS WEATHER
OUTLOOK FOR NW CWA. CANNOT FORGET THE FAR NORTHEAST CWA AS WELL WITH
WINDS SHIFTING ONSHORE AND LEADING TO POTENTIAL OF DOMINANT BAND OF
SNOW IMPACTING THOSE AREAS AS WELL...MAINLY EAST OF P53 INTO
NORTHERN LUCE COUNTY. AS MENTIONED IN PREVIOUS DISCUSSION...MORE
RESIDENCE TIME OVER THE WARMER LAKE WATERS AND A BIT MORE WARMER
AIRMASS OVERALL MAY ACT TO LIMIT SNOW AMOUNTS COMPARED TO WHAT IS
EXPECTED TO OCCUR OVER NW UPR MICHIGAN. SOME SNOW ACCUMULATIONS ARE
LIKELY THOUGH.
LATER MONDAY NIGHT AND FOR SURE INTO MID MORNING TUESDAY...WILL SEE
LK EFFECT DIMINISH SIGNIFICANTLY MAINLY DUE TO DEPARTURE OF MOISTURE
ABOVE H85 AND AS STEADILY WARMING TEMPS AT TOP OF 5KFT INVERSION.
MOISTURE DECREASES DRAMATICALLY BY 12Z TUESDAY...ESPECIALLY IN THE
WEST. COULD EVEN SEE SKIES BECOME MOSTLY CLEAR OVER FAR SOUTH AWAY
FROM EFFECTS OFF THE LAKE. IN ANY CASE...WHAT LAKE EFFECT IS LEFT
AT THAT TIME WILL BE SHADOW OF WHAT WILL HAVE JUST OCCURRED 12 HR
PREVIOUSLY. NO REAL CHANGES TO POPS FOR MONDAY THROUGH MONDAY NIGHT
AND INTO TUESDAY...JUST SOME TWEAKING TO MATCH LATEST MODEL TRENDS.
DID INCREASE SNOW AMOUNTS SOME OVER NORTHWEST GIVEN INCREASING
CONFIDENCE IN OVERALL SCENARIO. CURRENTLY FORECASTED SNOW AMOUNTS
SUPPORT ADVISORY HEADLINES EVENTUALLY. THAT SAID...CERTAINLY
POSSIBLE THAT AT LEAST ISOLD LOCATIONS FROM ONTONAGON THROUGH
HOUGHTON AND KEWEENAW COUTNIES MAY SEE WARNING CRITERIA SNOWFALL
FROM THIS EARLY SEASON LAKE SNOW EVENT. ON A SIDE NOTE...WINDS IN
THE STRONGER CONVERGENCE AREAS ACROSS KEWEENAW MAY TOP OUT 30-40 MPH
ON MONDAY AND MONDAY EVENING. SO IN ADDITION TO THE HEAVY SNOW COULD
ALSO SEE STRONG/GUSTY WINDS WITHIN THOSE HEAVIER SNOW SQUALLS.
PLAN TO MENTION THIS IN THE HAZARDOUS WEATHER OUTLOOK.
REST OF LONG TERM...PRETTY QUIET OVERALL AS PACIFIC FLOW ALOFT WILL
BE IN CONTROL. SFC HIGH BUILDS IN LATER TUESDAY AND MOVES EAST ON
WEDNESDAY. LOWERED MINS ON TUESDAY NIGHT WITH COLD AIRMASS IN PLACE.
MID CLOUDS INCREASE LATE BUT SEEMED REASONABLE TO START THE NIGHT
TEMPS COULD FALL OFF INTO THE TEENS BEFORE BECOMING MORE STEADY LATE.
WEDNESDAY MAY END UP FAIRLY CLOUDY...BUT REALLY WHAT ELSE IS NEW
LATELY. A LOT OF MID CLOUDS SHOW UP IN THE MODELS...BUT DRY SUB H85
AIR DUE TO LINGERING AFFECTS OF THE SFC HIGH AND NOT VERY STRONG
LIFT ALOFT RESULT IN KEEPING DRY FORECAST GOING FOR CWA. WEAK WARM
AIR ADVECTION AND ADDITIONAL MOISTURE ADVECTION AHEAD OF SFC TROUGH
MOVING ACROSS ONTARIO BY THURSDAY MORNING COULD PROVIDE CHANCE FOR
SOME LGT SNOW/FLURRIES ON WEDNESDAY NIGHT. DRY FORECAST TO CLOSE THE
WEEK AND THROUGH NEXT SATURDAY WITH LACK OF SYSTEMS MOVING THROUGH
IN THE WESTERLY FLOW. SW FLOW IN LOWER LEVELS FRIDAY/SATURDAY MAY
ALLOW FOR TEMPS TO PUSH SLIGHTY ABOVE NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1256 PM EST SUN NOV 11 2012
CONDITIONS WILL CONTINUE TO DETERIORATE AS SHRA OVERSPREADS WESTERN
AND CENTRAL UPPER MI IN RELATION TO A DISTURBANCE RIDING NEWD ALONG
COLD FRONT...CURRENTLY OVER FAR WESTERN UPPER MI. KEPT TAF SITES
WITHIN FUEL ALTERNATE CATEGORIES THROUGH THIS EVENING...THOUGH AS
MENTIONED BY PREVIOUS FORECAST...LIFR CONDITIONS CAN NOT BE RULED
OUT AT SOME POINT...ESPECIALLY AT CMX THIS AFTN/EVNG WITH GUSTY
UPSLOPE W WIND BEHIND THE COLD FROPA. EXPECT THE ARRIVAL OF DRIER
AIR TO CAUSE THE PCPN TO DIMINISH JUST AS ENUF COLD AIR SURGES INTO
THE AREA TO CHANGE THE RA TO SN. THE BEST CHC FOR HEAVIER -SHSN
LATER TNGT WL BE AT THE MORE EXPOSED CMX LOCATION...WHERE GUSTY
WINDS WL LINGER AS WELL. OTHERWISE...DRY AIR WILL CONTINUE TO
IMPROVE CIG CONDITIONS TO VFR AT KIWD AND KSAW BY MONDAY MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 533 AM EST SUN NOV 11 2012
EXPECT S WINDS UP TO 25 TO 30 KTS...STRONGEST OVER THE E HALF UNDER
TIGHTER PRES GRADIENT...IN ADVANCE OF AN APPROACHING COLD FRONT TO
SHIFT TO THE W FOLLOWING THE COLD FROPA OVER THE W THIS AFTERNOON AND
THEN OVER THE CENTRAL AND E TONIGHT AS MUCH COLDER AIR FLOWS OVER THE
RELATIVELY WARM LAKE WATERS AND ENHANCES MIXING OF STRONGER WINDS TO
THE SURFACE.
PRESSURE GRADIENT STAYS TIGHT ON MONDAY WITH WEST WINDS UP TO 30 KTS
AND OCCASIONAL GALE GUSTS TO 35 KTS. PRESSURE GRADIENT SLACKENS
MONDAY NIGHT AND TUESDAY WITH WINDS DIMINISHING BLO 25 KTS. A LOW
PRESSURE TROUGH WILL PUSH ACROSS NORTHERN ONTARIO ON THURSDAY. SOUTH
WINDS AHEAD OF THE TROUGH COULD REACH 25 KTS OVER EASTERN SECTIONS
OF LK SUPERIOR WEDNESDAY AND WEDNESDAY NIGHT. WINDS TO FINISH UP THE
WEEK WILL BE BLO 20 KTS AS PRESSURE GRADIENT DIMINISHES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...JMW
MARINE...KC/JLA
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
347 PM CST SUN NOV 11 2012
.DISCUSSION...
Short Range (Tonight through Tuesday):
Impressive upper trough moving east through the Plains late this
afternoon. Best lift/sensible weather occurring well downstream over
the mid MO River Valley where mixed precipitation is falling. The
combination of significant cold air advection through the entire
column, elevated frontogenesis and increasing upper level jet
dynamics has allowed sleet to form on the western edge of the rain
shield. Short range models, HRRR, RAP and NAM all clear out the
precipitation over the eastern counties by 03Z. Have slowed down the
end of the precipitation slightly due to the positive tilt of the
upper trough and the associated strong upper level jet dynamics.
Weather looking pretty tranquil after the upper trough axis passes
through the CWA early Monday. Strong subsidence on the back side of
the trough should greatly limit the effects of a secondary vorticity
lobe sliding through eastern NE/KS during the day. Although the
models show warm air advection occurring on Monday its effects will
be muted due to such a cold start to the day.
A semi-zonal flow pattern will ensue over the central U.S. by Monday
night and continue into mid week. A fast moving shortwave embedded
within this flow will streak through KS/NE/IA/MO on Tuesday,
However, moisture will be limited, especially within the boundary
layer so should only see a modest pick up in clouds with moderate
warm air advection resulting in seasonally average temperatures.
MJ
Medium Range (Wednesday through Sunday):
A few troughs may drop through primarily zonal flow during the
latter half of the week; however, with dry surface high pressure
sitting over the southeastern U.S, precipitation chances look very
low through at least Saturday. Temperatures should hover around to a
few degrees below normal in the absence of any amplified troughing
or ridging through the Plains, with highs mainly in the 50`s and
lows in the 30`s.
As the surface high weakens and gradually slides eastward Saturday,
both the EC and GFS bringing a shortwave trough into Nebraska and
eastern Kansas, potentially fueling widespread but light, scattered
precipitation especially across the western half of the CWA. Aloft,
temperatures look warm enough for a liquid precipitation type across
the region, especially without any deep cold air poised to filter in
behind the system.
Laflin
&&
.AVIATION...
For the 18Z TAFS...The back edge of the precipitation shield, which
has some sleet and snow mixed in with the rain, has moved east of
KSTJ and will likely be east of KMCI at the the start of the
forecast period. Will mention mix of rain/sleet for KMKC for another
hr. Otherwise, low MVFR cigs for most of the afternoon with
improvement to high end MVFR by late afternoon. Clearing line should
reach the terminals early this evening. Gusty northwest winds will
drop off by around 00z with winds gradually backing to the southwest
overnight.
MJ
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1035 AM CST SUN NOV 11 2012
.DISCUSSION.../ISSUED AT 1035 AM CST/
EARLIER FORECAST WAS PRETTY GOOD. HAVE BRIGHTENED UP SKIES A LITTLE
AND HELD TEMPERATURES DOWN A TAD BUT PRETTY SMALL CHANGES. EARLIER
WINDS ARE LOOKING GOOD...WINDY BUT A LITTLE BELOW ADVISORY CRITERIA.
EARLY OUTLOOK FOR THREAT OF MINIMAL LIGHT SNOW LOOKS OK BUT IT MAY
BE JUST SOME FLURRIES.
&&
.AVIATION.../FOR THE 12Z TAF ISSUANCE/
NAM AND RUC SHOW A STOUT INVERSION AROUND 900MB UNTIL AROUND 9-10 AM
LOCAL TIME AT FSD AND SUX WITH DRYING BELOW THE INVERSION. HON
SOUNDINGS SHOW THE INVERSION LIFTING AROUND 7-8AM LOCAL. WILL START
RAISING CIGS AROUND THE AFOREMENTIONED TIMES. SOME BREAKS IN THE
CLOUDS WILL BE POSSIBLE LATER THIS MORNING BUT ANOTHER SLUG OF
MOISTURE RETURNS AS WELL AS AN UPPER LEVEL TROF AND CLOUDS WILL FILL
BACK IN IN THE AFTERNOON THROUGH THE EVENING WITH VFR EXPECTED.
GUSTY WIND WILL CONTINUE THROUGH THE DAY AND INTO THE EARLY EVENING
WITH GUSTS STARTING TO SUBSIDE A FEW HOURS AFTER SUNSET.
&&
.PREV DISCUSSION.../ISSUED AT 331 AM CST/
MAJOR TROUGH MOVING THROUGH THIS MORNING WITH SUBSIDENCE BECOMING
STRONGER THROUGH THE DAY. OUTSIDE OF A FEW FLURRIES NOT REALLY
EXPECTING MUCH IN THE WAY OF PRECIPITATION. VERY COLD AIR POURING
INTO THE REGION WITH WIND CHILL VALUES INT HE SINGLE DIGITS WEST OF
INTERSTATE 29. VERY LITTLE REBOUND TODAY WITH CONTINUED COLD AIR
ADVECTION AND SOME CLOUD COVER TO SHAKE OFF SO ONLY EXPECTING A
REBOUND OF 5 TO 8 DEGREES FROM THIS MORNINGS LOW TEMPERATURE.
SO...LOWERED HIGHS A COUPLE OF DEGREES...ESPECIALLY WEST WHERE A
LITTLE ACCUMULATING SNOW MAY HAVE FALLEN.
JUST AS THE CLOUDS SCOUR OUT FROM SOUTH TO NORTH TODAY ADDITIONAL
CLOUD COVER WILL BUILD SOUTH FROM NORTH DAKOTA AS THE COLD CORE LOW
BUILDS SOUTHWARD. WILL CONTINUE A SMALL CHANCE FOR SNOWFALL NORTH OF
INTERSTATE 90 AS THIS DOES SO WITH MODERATELY STEEP LAPSE RATES
DEVELOPING. IF THIS COLD CORE WAS MOVING THROUGH DURING THE DAY
CONFIDENCE IN A FEW SNOW SHOWERS WOULD BE A LITTLE HIGHER. NOT
AIMING TOO LOW WITH CLOUD COVER BUT STILL BELIEVE TEENS TO LOWER 20S
WILL BE COMMON.
BY MONDAY A GOOD MIXING WESTERLY WIND AND DECREASING CLOUD COVER
WILL ALLOW FOR SOME WARMING...AND INCREASED HIGHS JUST A BIT TO
ACCOUNT FOR POTENTIALLY DECENT MIXING CONDITIONS...BUT STILL ONLY IN
THE 30S.
WINDS WILL TURN TO THE SOUTH MONDAY NIGHT INTO TUESDAY ALLOWING FOR
LESS COLD CONDITIONS. LOWS STILL IN THE TEENS TO MID 20S WITH HIGHS
CLIMBING BACK INTO THE 40S. IF THE NAM LOW LEVEL THERMAL FIELD IS A
LITTLE CLOSER AREAS IN THE SOUTHERN CWA COULD CLIMB INTO THE LOWER
50S.
IN THE LATTER PERIODS(WED/SAT)...OVERALL LOOKS FAIRLY QUIET THROUGH
THE PERIOD WITH SPLIT FLOW DEVELOPING EARLY AND SOME HINT OF A WEAK
SOUTHERN STREAM WAVE MOVING IN ON SATURDAY. GENERALLY SPLIT FLOW IS
FAIRLY QUIET SO WILL CONTINUE WITH NO REAL THREAT FOR
PRECIPITATION...EXCEPT CONTINUE THE POP FOR SATURDAYS WEAK WAVE.
OTHERWISE...TEMPERATURES FAIRLY SEASONAL THROUGH THE PERIOD WITH NO
MAJOR COOL DOWNS OR WARM UPS...SO WILL BE SHOOTING FOR HIGHS MAINLY
IN THE 40S TO LOWER 50S AND LOWS IN THE 20S TO LOWER 30S WITH THE
POTENTIAL FOR SOME WARMER LOWS ON SATURDAY MORNING AHEAD OF THE
INCOMING WAVE. /08
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
324 PM CST SUN NOV 11 2012
.DISCUSSION...
CF IS THROUGH WACO AND TEMPLE AND HEADED FOR CLL 5-6 PM. RAP AND
LOCAL WRF ARE IN GOOD AGREEMENT THAT THE FRONT WILL REACH IAH
AROUND 9 PM AND THEN NEAR THE COAST AROUND MIDNIGHT. THE CAP HAS
HELD STRONG ACROSS SE TX TODAY...WITH THE ONLY TSTMS NORTH OF THE
AREA SO FAR AND WITHIN THE SVR TSTM WATCH AREA. EXPECT TO SEE SOME
TSTMS DEVELOP ACROSS NORTHERN AREAS DURING THE NEXT COUPLE HOURS
AS THE FRONT APPROACHES. STILL A SLIGHT RISK OF SVR TSTMS ACROSS
NORTHERN AREAS AND THIS THREAT APPEARS TO BE UNTIL AROUND 9
PM...WITH ISOLATED STRONG WIND GUSTS A POSSIBILITY WITH ANY
STRONG/SEVERE STORM THAT DEVELOPS. LOWERED POPS A LITTLE ACROSS
SOUTHWEST AREAS THIS EVENING AS THE CAP MAY BE PROBLEMATIC FOR
PRECIP...EVEN WITH THE BOUNDARY.
PREFER THE GFS FOR THE FORECAST...ALTHOUGH NO SIGNIFICANT
DIFFERENCES BETWEEN THE ECMWF/GFS AS THE GFS HAS TRENDED COLDER
TOWARD THE END OF THE WEEK WITH NW FLOW ALOFT AND ANOTHER
REINFORCING COOL PUSH ON WED BEHIND A SHORT WAVE TROF. STILL DO
NOT THINK WE WILL SEE RAIN WITH THIS DISTURBANCE ACROSS SOUTHERN
AREAS ON TUE NIGHT AS THE ATMOSPHERE IS VERY DRY IN THE LOW-
LEVELS. WE WILL SEE SOME ADDITIONAL MID-LEVEL CLOUD COVER. MADE
SOME COOLER ADJUSTMENTS TO THE FORECAST ESPECIALLY FOR MIN TEMPS
THU...FRI...AND SAT. WILL SEE MIN TEMPS IN THE MID 30S ACROSS
NORTHERN AREAS TUE THROUGH THU MORNINGS.
THE NEXT RAIN CHANCE APPEARS TO BE NEXT WEEKEND AS MOISTURE
RETURNS AND A MID/UPPER TROUGH MOVES ACROSS. 33
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 47 66 37 64 39 / 40 0 0 0 0
HOUSTON (IAH) 56 69 41 66 42 / 60 0 0 0 0
GALVESTON (GLS) 61 71 50 66 49 / 60 0 0 0 0
&&
.AVIATION...
DID NOT MAKE A LOT OF CHANGES WITH THIS 18Z TAF PACKAGE AS TIMING OF
THE COLD FRONT REMAINS ON PACE FOR PASSAGE AT CLL AROUND 00Z THEN TO
THE COAST/GLS BY 08Z. STILL SOME QUESTIONS AS TO THE STRENGTH OF THE
CAP FOR LOCATIONS SOUTH OF I-10 BUT DID KEEP VCTS IN FOR FROPA. VERY
RAPID CLEARING BEHIND THE FRONT WITH VFR AREAWIDE BY SUNRISE. 41
&&
.MARINE...
MODERATE/STRONG ONSHORE WINDS...BUT THE MAIN ISSUE FOR THE AFTERNOON
HAS BEEN THE ELEVATED SEAS. DID RAISE A SMALL CRAFT ADVISORY FOR ALL
OF THE COASTAL WATERS TODAY (AS WELL AS KEEPING AN SCEC FOR BAYS) AS
WE HEAD INTO TONIGHT. WE COULD GET A BRIEF BREAK WITH THESE ELEVATED
WINDS/SEAS JUST AHEAD OF THE FRONT BUT CONDITIONS EXPECTED TO RATCH-
ET BACK UP BY SUNRISE AS THE COLDER AIR MOVES INTO THE MARINE ZONES.
SCA FLAGS MAY NEED TO BE EXTENDED FOR THE BAYS BEHIND THE COLD FRONT
SHOULD THE MODELS VERIFY. HIGH PRESSURE BUILDING IN OVER THE AREA TO
HELP LOWER WINDS/SEAS BY TUES AFTN. 41
&&
.FIRE WEATHER...
SOME ISSUES OF CONCERN REGARDING CONDITIONS IN THE WAKE OF THE FRONT
FOR MON. VERY DRY AIR MOVING DOWN OFF THE PLAINS COULD LOWER MINIMUM
AFTN RH LEVELS TO AROUND 25% FOR MOST INLAND AREAS MON BUT WINDS ARE
LIKELY TO REMAIN LOW (10-15MPH) DURING THIS SAME TIME FRAME. HOWEVER
INTERESTS SHOULD CONTINUE TO MONITOR THE FCST. 41
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION THROUGH TUESDAY AFTERNOON
FOR THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...
WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20
NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL 6 PM CST TUESDAY FOR THE FOLLOWING
ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL
20 NM TO 60 NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20
TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...33
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
201 PM CST SUN NOV 11 2012
.SHORT TERM...THROUGH WEDNESDAY
201 PM CST SUN NOV 11 2012
MAIN FORECAST CONCERN IS ON TEMPERATURES THE NEXT FEW DAYS DUE TO
THE SHARPLY COLDER AIR THAT HAS BEEN ADVECTING IN TODAY.
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT
ANALYSIS SHOWED RIDGING BUILDING UP ALONG THE WEST COAST OF THE
U.S....DEEP TROUGHING FROM MANITOBA SOUTHWESTWARD INTO THE TEXAS
PANHANDLE...AND STRONG RIDGING ALONG THE EAST COAST OF THE U.S..
WITHIN THE SOUTHWEST FLOW AHEAD OF THE DEEP TROUGH...A 120KT JET
STREAK WAS PRESENT NEAR 250MB OVER EASTERN MINNESOTA. THE
COMBINATION OF UPPER DIVERGENCE IN THE RIGHT ENTRANCE REGION OF
THIS JET...VARIOUS SHORTWAVES RIDING THROUGH THE SOUTHWEST
FLOW...A STRONG LOW TO MID-LEVEL FRONTOGENESIS ZONE NOTED IN RAP
ANALYSES AND IN 925MB AND 850MB VWP AND PROFILER DATA...AND
PLENTIFUL MOISTURE INDICATED FROM GOES DERIVED PRECIPITABLE WATER
DATA SHOWING AROUND 1 INCH IS AIDING IN WIDESPREAD PRECIPITATION.
REGIONAL RADAR IMAGERY SHOWED THE PRECIPITATION FROM EASTERN IOWA
THROUGH MUCH OF WISCONSIN AND A SMALL PORTION OF SOUTHEAST
MINNESOTA. MUCH OF THE PRECIPITATION IS FALLING AS RAIN...THOUGH
THE WESTERN EDGE HAS MIXED WITH SLEET AND SNOW DUE TO
DRAMATICALLY COLDER AIR FLOWING IN ON NORTHWEST WINDS. SURFACE
TEMPERATURES ARE MOSTLY IN THE TEENS AND 20S IN THE DAKOTAS INTO
WESTERN MINNESOTA. MEANWHILE...AHEAD OF THE SURFACE COLD FRONT
INDICATED JUST EAST OF THE FORECAST AREA...READINGS ARE IN THE LOW
TO MID 60S FROM GREEN BAY TO MADISON. 12Z RAOBS REFLECTED THE
SHARP TEMPERATURE GRADIENT TOO...WITH 850MB READINGS OF 11C AT
GRB...3C AT MPX...-12C AT ABR AND -15C AT BIS. LAST ITEM OF NOTE
IS SKIES THAT HAVE CLEARED OUT OVER EASTERN SOUTH DAKOTA INTO
SOUTHWEST MINNESOTA.
TONIGHT AND MONDAY...THE DEEP UPPER TROUGH OVER THE PLAINS IS
PROGGED TO PROGRESS EASTWARD THROUGH THIS PERIOD...WITH ITS AXIS
SITTING OVER THE AREA MONDAY MORNING...THEN SHIFTING INTO THE GREAT
LAKES MONDAY AFTERNOON. WITH THIS UPPER TROUGH WILL COME THE COLDER
AIR WITH 850MB AND 925MB TEMPS FORECAST TO TANK BY 12Z TO -12 TO
-16C AND -8 TO -11C RESPECTIVELY. THESE ARE 2 STANDARD DEVIATIONS
BELOW NORMAL. THUS...EXPECT A MUCH COLDER NIGHT TONIGHT AND DAY ON
MONDAY. THE TEMPERATURES WILL STILL BE OFF THE COLDEST HIGH
TEMPERATURE FOR A DAY AT LA CROSSE AND ROCHESTER OF 14 AND 11
RESPECTIVELY...SET AFTER THE ARMISTICE DAY STORM OF 1940. WITH THE
EASTWARD PROGRESSION OF THE UPPER TROUGH...ANTICIPATING
PRECIPITATION TO END WEST TO EAST THIS EVENING. A LITTLE SNOW IS
POSSIBLE...BUT THE WARM GROUND SHOULD LIMIT ACCUMULATIONS TO A HALF
INCH OR LESS...MOSTLY ON GRASSY SURFACES. SKIES WILL CLEAR FOR
MOST LOCATIONS TONIGHT AS THE DRIER AIR IN SOUTH DAKOTA AND
SOUTHWEST MINNESOTA PUSHES IN. HOWEVER...A SURFACE TROUGH
ACCOMPANYING THE CORE OF THE COLD AIR IS SLATED TO CROSS THE AREA ON
MONDAY...BRINGING WITH IT A RAPID INCREASE OF CLOUDS. IN
ADDITION...THE COMBINATION OF DIURNAL HEATING AND THE CLOUDS BEING
SITUATED IN THE DENDRITIC GROWTH ZONE WILL LIKELY LEAD TO
FLURRY/SNOW SHOWER DEVELOPMENT. BEST CHANCE OF SEEING SOME LIGHT
SNOW SHOWER ACCUMULATION WILL BE NORTH OF I-90 WHERE DEEPER MOISTURE
EXISTS.
MONDAY NIGHT AND TUESDAY...THE UPPER RIDGE THAT IS BUILDING ALONG
THE WEST COAST OF THE U.S. CURRENTLY LOOKS TO FLATTEN OUT AND PUSH
EAST INTO THE FORECAST AREA BY TUESDAY. THIS IN RESPONSE TO NUMEROUS
SHORTWAVES COMING OFF THE EAST PACIFIC. ACCOMPANYING THE FLATTENING
UPPER RIDGE WILL BE A SURFACE HIGH PRESSURE RIDGE AS WELL AS WARMER
925-850MB AIR. BY 00Z WEDNESDAY...850MB TEMPS SHOULD HAVE CLIMBED TO
0 TO -3C PER MODEL CONSENSUS...MUCH WARMER THAN THOSE SEEN ON
MONDAY. THEREFORE...AFTER WHAT WILL LIKELY BE A CHILLY NIGHT MONDAY
NIGHT DUE TO THE COLD START...WINDS DROPPING OFF TO CALM WITH THE
SURFACE RIDGE AND SKIES CLEARING OUT...TEMPERATURES SHOULD REBOUND
INTO THE MID 30S TO PERHAPS EVEN LOWER 40S. WARMEST READINGS WOULD
OCCUR ALONG/WEST OF THE MISSISSIPPI RIVER DUE TO THE WARMER AIR
COMING IN THERE FIRST. DROPPED LOWS 5 TO 10 DEGREES MONDAY NIGHT
FROM THE PREVIOUS FORECAST DUE TO THE FAVORABLE RADIATIONAL
COOLING CONDITIONS EXPECTED. THE FORECAST LOW TEMPERATURES LEAN
CLOSELY TOWARDS THE MET GUIDANCE. SOME INCREASE IN CLOUDS OCCURS
LATE ON TUESDAY WITH THE WARMER AIR MOVING IN...ALONG WITH A
SHORTWAVE TROUGH ENTERING THE NORTHERN PLAINS...BUT THESE SHOULD
NOT HAMPER MIXING OR PRODUCE ANY PRECIPITATION DUE TO LOW LEVEL
DRY AIR PRESENT.
TUESDAY NIGHT AND WEDNESDAY...MODELS PROG THE SHORTWAVE TROUGH IN
THE NORTHERN PLAINS LATE TUESDAY TO MOVE NORTHEAST AND ACROSS THE
AREA WEDNESDAY MORNING. PRECIPITABLE WATER VALUES SUGGEST SOMEWHAT
LIMITED MOISTURE WITH THE TROUGH...ANYWHERE FROM 0.3-0.5 INCHES...
HIGHEST JUST NORTH OF THE FORECAST AREA. ISENTROPIC LIFT PROGS ON
THE 280-290K SURFACES COMBINED WITH CONDENSATION PRESSURE DEFICITS
FORECAST BEST JUXTAPOSITION IS JUST NORTH OF THE FORECAST AREA.
THUS...THINKING ANY PRECIPITATION POTENTIAL WILL ALSO STAY JUST
NORTH OF THE FORECAST AREA...SIMILAR TO WHAT DERIVED QPF OUTPUT
SHOWS FROM THE 11.12Z NAM/GFS/ECMWF AND 11.15Z SREF MEAN.
THEREFORE...HAVE STAYED WITH A DRY FORECAST. ALTHOUGH NO
PRECIPITATION IS ANTICIPATED...AN INCREASE OF CLOUDS WILL OCCUR FOR
TUESDAY NIGHT INTO WEDNESDAY MORNING...BEFORE SUBSIDENCE IN THE WAKE
OF THE SHORTWAVE TROUGH HELPS CLEAR THEM OUT WEDNESDAY AFTERNOON.
WITH MORE CLOUDS TUESDAY NIGHT...MUCH WARMER TEMPERATURES ARE
EXPECTED COMPARED TO MONDAY NIGHT. STAYED WITH A BLEND OF GUIDANCE
FOR LOWS. 850MB TEMPS HOVERING NEAR 0C ON WEDNESDAY AND THE
AFTERNOON SUN SHOULD ALLOW TEMPERATURES TO CLIMB UP INTO THE LOW TO
MID 40S IN MOST LOCATIONS.
.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY
201 PM CST SUN NOV 11 2012
THE LONG TERM FORECAST LOOKS GENERALLY QUIET WEATHER WITH
TEMPERATURES NEAR TO SLIGHTLY ABOVE NORMAL. UPPER LEVEL PATTERN
SUGGESTED BY THE 11.12Z ECMWF/GFS/CANADIAN AND GFS
ENSEMBLES...ALONG WITH THEIR PREVIOUS RUNS...FEATURES A SPLIT
FLOW PATTERN...WITH THE NORTHERN STREAM MOSTLY TRACKING ACROSS
SOUTHERN CANADA AND THE SOUTHERN STREAM GOING ACROSS THE SOUTHERN
U.S.. THERE IS SOME AMPLIFICATION THAT TAKES PLACE TO THE NORTHERN
STREAM FOR THE END OF THE WEEKEND IN RESPONSE TO A DEEP TROUGH
FORMING OVER THE EAST PACIFIC...HELPING TO KEEP A PACIFIC FLOW OF
AIR ACROSS THE CONUS. THERE ARE A FEW HIGHLIGHTS IN THE EXTENDED.
FIRST...A SHORTWAVE TROUGH IS INDICATED BY ALL MODELS TO CROSS THE
AREA ON THURSDAY WITH A WEAK COLD FRONT ACCOMPANYING IT. BEST
FORCING WITH THIS TROUGH LOOKS TO OCCUR NORTH OF THE FORECAST
AREA...AND IN CONJUNCTION WITH LIMITED MOISTURE...HAVE KEPT THE
FORECAST DRY. THE NEXT HIGHLIGHT IS A SHORTWAVE ALONG THE
SUBTROPICAL JET WHICH MODELS HAVE BEEN ADVERTISING MOVING INTO THE
CENTRAL PLAINS SATURDAY NIGHT...THEN SLOWLY PROGRESSING EASTWARD
ON SUNDAY. IT APPEARS ANY FORCING AND PRECIPITATION FROM THIS
SHORTWAVE WILL STAY TO THE SOUTHWEST...THUS HAVE KEPT SATURDAY
NIGHT THROUGH SUNDAY DRY.
&&
.AVIATION...THROUGH 18Z MONDAY
1147 AM CST SUN NOV 11 2012
A STRONG COLD FRONT WILL MOVE QUICKLY EAST THROUGH CENTRAL
AND SOUTHWEST WISCONSIN. THIS FRONT HAS ALREADY CLEARED BOTH TAF
SITES. FOR THIS AFTERNOON...NORTHWEST WINDS WILL BE SUSTAINED IN
THE 10 TO 20 KNOT RANGE AND THE WINDS WILL OCCASIONALLY GUST UP TO
25 KNOTS. STRONG FRONTOGENESIS ON THE BACK SIDE OF THIS FRONT WILL
KEEP PRECIPITATION AT KLSE THROUGH 11.04Z. SOUNDINGS SUGGEST THAT
THE RAIN WILL CHANGE OVER TO SLEET AND SNOW AROUND 11.22Z...AND
TO SNOW BY 12.00Z. UP TO A HALF INCH OF SNOW ACCUMULATION WILL BE
POSSIBLE MAINLY ON GRASSY SURFACES. CEILINGS WILL BE PRIMARILY
IFR AND VISIBILITIES MVFR. MEANWHILE AT KRST...THEY ARE ON THE
WESTERN EDGE OF THIS PRECIPITATION BAND. EXPECTING THE RAIN TO
CHANGE OVER TO A MIX OF SLEET AND SNOW BY 11.19Z...AND TO SNOW BY
11.21Z. NOT EXPECTING ANY ACCUMULATION OF SNOW. VISIBILITIES WILL
BE MAINLY VFR AND OCCASIONALLY DROP TO MVFR. CEILINGS WILL START
OUT AS IFR AND THEN RAISE TO MVFR BY LATE AFTERNOON.
FOR TONIGHT...EXPECT SKIES TO CLEAR AT KRST AROUND 12.02Z AND AT
KLSE AROUND 12.06Z.
ON MONDAY MORNING...A SHORT WAVE TROUGH WILL MOVE INTO THE REGION.
AS IT APPROACHES A MVFR DECK WILL MOVE INTO KRST AROUND 12.11Z AND
KLSE AROUND 12.12Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
201 PM CST SUN NOV 11 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1150 AM CST SUN NOV 11 2012
.SHORT TERM...TODAY
607 AM CST SUN NOV 11 2012
BASED ON THE LAST FEW RUNS OF RAP SOUNDINGS ACROSS THE
REGION...HAVE DECIDED TO PULL THE FREEZING RAIN FROM THE FORECAST
FOR TODAY SINCE IT APPEARS THAT SURFACE TEMPERATURES WILL HAVE A
HARD TIME TO DROP BELOW FREEZING BEFORE THE WARM LAYER COOLS. THIS
MEANS THAT THE RAIN WILL CHANGE OVER TO A PERIOD OF SLEET/SNOW
PELLETS BEFORE CHANGING OVER TO ALL SNOW THIS AFTERNOON/EVENING.
WILL HAVE TO MONITOR THE BACK SIDE OF THE PRECIPITATION SHIELD IN
CASE ICE CREATION IS LOST IN THE -10C TO -20C DENDRITIC GROWTH
ZONE AND SOME DRIZZLE FALLS IN SUB FREEZING AIR.
.LONG TERM...WEDNESDAY THROUGH SATURDAY
313 AM CST SUN NOV 11 2012
HIGH PRESSURE SETS UP ACROSS THE EASTERN HALF OF THE US ON
WEDNESDAY AND LINGERS THROUGH NEXT WEEKEND AND SHOULD LEAVE DRY
CONDITIONS THROUGH THE PERIOD. WITH THE UPPER MISSISSIPPI RIVER
VALLEY BEING ON THE WESTERN PERIPHERY OF THE RIDGE THERE SHOULD BE
SOUTHERLY SURFACE TO LOW LEVEL WINDS THAT WILL KEEP TEMPERATURES
AT ABOUT NORMAL.
&&
.AVIATION...THROUGH 18Z MONDAY
1147 AM CST SUN NOV 11 2012
A STRONG COLD FRONT WILL MOVE QUICKLY EAST THROUGH CENTRAL
AND SOUTHWEST WISCONSIN. THIS FRONT HAS ALREADY CLEARED BOTH TAF
SITES. FOR THIS AFTERNOON...NORTHWEST WINDS WILL BE SUSTAINED IN
THE 10 TO 20 KNOT RANGE AND THE WINDS WILL OCCASIONALLY GUST UP TO
25 KNOTS. STRONG FRONTOGENESIS ON THE BACK SIDE OF THIS FRONT WILL
KEEP PRECIPITATION AT KLSE THROUGH 11.04Z. SOUNDINGS SUGGEST THAT
THE RAIN WILL CHANGE OVER TO SLEET AND SNOW AROUND 11.22Z...AND
TO SNOW BY 12.00Z. UP TO A HALF INCH OF SNOW ACCUMULATION WILL BE
POSSIBLE MAINLY ON GRASSY SURFACES. CEILINGS WILL BE PRIMARILY
IFR AND VISIBILITIES MVFR. MEANWHILE AT KRST...THEY ARE ON THE
WESTERN EDGE OF THIS PRECIPITATION BAND. EXPECTING THE RAIN TO
CHANGE OVER TO A MIX OF SLEET AND SNOW BY 11.19Z...AND TO SNOW BY
11.21Z. NOT EXPECTING ANY ACCUMULATION OF SNOW. VISIBILITIES WILL
BE MAINLY VFR AND OCCASIONALLY DROP TO MVFR. CEILINGS WILL START
OUT AS IFR AND THEN RAISE TO MVFR BY LATE AFTERNOON.
FOR TONIGHT...EXPECT SKIES TO CLEAR AT KRST AROUND 12.02Z AND AT
KLSE AROUND 12.06Z.
ON MONDAY MORNING...A SHORT WAVE TROUGH WILL MOVE INTO THE REGION.
AS IT APPROACHES A MVFR DECK WILL MOVE INTO KRST AROUND 12.11Z AND
KLSE AROUND 12.12Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
313 AM CST SUN NOV 11 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...BOYNE
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1119 AM CST SUN NOV 11 2012
.UPDATE...INTERESTING DAY AHEAD AS A STRONG COLD FRONT APPROACHES
FROM THE WEST AHEAD OF A DEEP UPPER-LEVEL TROUGH AS SEEN IN THE
MID- AND UPPER-LEVEL MODEL ANALYSES. MAIN CONCERNS TODAY WILL BE
TIMING OF THE SURFACE COLD FRONT...AND ITS ASSOCIATED IMPACT ON
TEMPS AND WINDS...AND WEATHER/POPS. NO CHANGES IN HEADLINES IN
THIS UPDATE. WIND ADVISORY IN EFFECT FOR SOUTHEAST AND PORTIONS
SOUTH CENTRAL TODAY ENDING AT 6PM...WITH FAR EAST COUNTIES ENDING
AT 8PM.
MSAS AND SFC OBS AS OF 9 AM SHOW SURFACE COLD FRONT POSITION ALONG
A LINE FROM JUST EAST OF EAU CLAIRE WI...TO NEAR DECORAH IA...TO
NEAR OTTUMWA IA. QUITE A TEMPERATURE GRADIENT...WITH TEMPERATURES
FALLING SHARPLY BEHIND FROPA. AT 9AM...LA CROSSE WAS 57 AHEAD OF
FROPA WITH PRESTON AT 41 BEHIND IT...TO 30 AT FAIRBAULT MN. VIS
SAT SHOWS A DENSE CLOUD SHIELD THAT IS INTO PORTIONS OF SE WI AND
GOES BACK TO EASTERN MN.
NOT MANY CHANGES MADE TO TEMPERATURE AND WIND FCST SO FAR IN THE
TODAY PERIOD. THOUGH UPDATED THE IMMEDIATE NEAR-TERM FOR
TRENDS...WITH TEMPS AND WINDS ON TRACK WITH GUIDANCE AND THE
EXPECTED FROPA STILL. WX/POPS WERE TRIMMED BACK IN THE NEAR-TIME
WITH RESPECT TO TIMING BASED ON RADAR AND HI-RES MODEL. WINDS WILL
HAVE TO BE WATCHED...AS NAM SOUNDINGS WITH GOOD LOW LEVEL
TEMPERATURE PROFILE SHOWED BORDERLINE CRITERIA BEING MET FOR GUSTS
AND SUSTAINED WINDS.
ELSEWHERE...POPS AND WX LATER IN THE AFTERNOON AND EVENING WERE
NOT CHANGED MUCH. WILL MONITOR THIS CLOSELY AS WELL. THE HI-RES
MODELS...LOCAL WRF AND HRRR...REFLECTIVITY FIELDS ARE HANDLING THE
NATURE AND TIMING OF THE PRESENT PRECIPITATION WELL COMPARED TO
THE RADAR MOSAIC...WILL BE USING THEM FOR POPS/WX TIMING IN
CONJUNCTION WITH RADAR. GIVEN ELEVATED CAPE...ISOLATED THUNDER
POSSIBLE TODAY...ESPECIALLY WITH THE LIFT AVAILABLE.
PRECIPITATION FIELD CORRESPONDS WELL WITH STRONG SURFACE
FRONTOGENESIS AND THE FIELDS LOCATION WITH RESPECT TO STRONG
LLJ/LLJ NOSE. AT NOON AT 850 HPA...A WIND MAX OF AROUND 60-65 KTS
IS SEEN GENERALLY SOUTH OF WI-IL BORDER...WITH LLJ STRENGTHENING
AND POSITIONING ITSELF OVER LAKE MICHIGAN THIS AFTERNOON. THE
DETERMINISTIC MODELS ARE GENERALLY SIMILAR IN POSITION AND SPEEDS
OF LLJ...THOUGH THE GFS AND RAP ARE A BIT STRONGER. DO EXPECT COLD
FRONT TO SPEED UP A BIT IN THE AFTERNOON...AS SFC LOW LIFTS AND
MOVES TO THE NE TOWARDS JAMES BAY.
&&
.AVIATION/18Z TAFS/...RAIN WITH MVFR/IFR CEILINGS AND VISIBILITIES
SHOULD REACH MADISON BY 20Z SUNDAY...AND THE EASTERN TAF SITES
BETWEEN 22Z SUNDAY AND 00Z MONDAY. ISOLATED THUNDERSTORMS ARE
EXPECTED ALONG THE LEADING EDGE OF THE STRONG COLD FRONT. THE
FRONT WILL REACH MADISON BY 23Z SUNDAY...AND THE EASTERN SITES
BETWEEN 01Z AND 03Z MONDAY. GUSTY SOUTH WINDS AHEAD OF THE FRONT
MAY GUST TO 39 KNOTS. WINDS WILL SLOWLY WEAKEN AND SHIFT WEST
BEHIND THE FRONT..WITH GUSTS TO 20 KNOTS STILL EXPECTED.
THE RAIN WITH MVFR/IFR CONDITIONS WILL LINGER THIS EVENING...THEN
END AT MADISON BY 06Z MONDAY...AND THE EASTERN SITES BY 10Z TO 11Z
MONDAY. MAY SEE LIGHT SNOW SHOWERS MIX IN BRIEFLY WITH THE RAIN
TOWARDS THESE ENDING TIMES...BUT NOT CONFIDENT ENOUGH TO MENTION
IN TAFS AT THIS TIME.
BRISK WEST WINDS WILL LINGER THROUGH MONDAY...GUSTING TO 25 KNOTS
AT TIMES. MVFR/IFR CEILINGS AND VISIBILITIES WILL IMPROVE TO VFR
AFTER THE PRECIPITATION ENDS...WITH SCATTERED TO BROKEN CUMULUS
AND FLURRIES EXPECTED BY MONDAY AFTERNOON.
&&
.MARINE...GALE WARNING CONTINUES UNTIL 03Z MONDAY ACROSS THE
NEARSHORE WATERS. TIGHT PRESSURE GRADIENT AND STRONG MIXING OF
WINDS FROM THE LOW LEVELS SHOULD BRING FREQUENT GUSTS TO 40 KNOTS
DURING THIS TIME. HIGH WAVES WILL RESULT...UP TO 4 TO 8 FEET.
THE STRONG COLD FRONT WILL MOVE THROUGH THIS AREA EARLY THIS
EVENING...WHICH WILL BRING SLIGHTLY WEAKER WINDS THAT WILL SHIFT
WEST AFTER THE FRONTAL PASSAGE. THESE WINDS WILL REMAIN GUSTY UP
TO 25 KNOTS TONIGHT AND MONDAY...LINGERING INTO MONDAY EVENING.
THESE WINDS WILL HELP WAVES SUBSIDE QUICKLY THIS EVENING...AND
REMAINING BELOW 4 FEET THROUGH MONDAY NIGHT.
THUS...A SMALL CRAFT ADVISORY WILL BE NEEDED AFTER THE GALE
WARNING EXPIRES AND THROUGH MONDAY/MONDAY EVENING.
&&
.PREV DISCUSSION... /ISSUED 343 AM CST SUN NOV 11 2012/
SHORT TERM...
TODAY-FORECAST CONFIDENCE HIGH
STRONG DYNAMIC SETUP COMING UP TODAY. DEEP UPPER TROUGH IN THE
ROCKIES PUSHES OUT INTO THE PLAINS WITH STRONG HEIGHT FALLS THIS
AFTERNOON. 500 MB 12 HOUR FALLS OF 60 TO 80 METERS SPREAD INTO
SOUTHERN WISCONSIN DURING THE AFTERNOON AS SURFACE COLD FRONT
APPROACHES.
ALTHOUGH SURFACE LOW NOT EXPECTED TO DEEPEN AS IT LIFTS INTO
NORTHWEST ONTARIO...VERY STRONG AND DEEP FRONTOGENESIS SHOWN BEHIND
SURGING COLD FRONT. THIS FRONT SHOULD ENTER FAR WEST AROUND NOON
AND THEN PROBABLY JUST EAST OF A LINE FROM FLD TO RFD BY 00Z MON.
BRIEF PERIOD OF NEAR WIND ADVISORY CONDITIONS ALREADY OCCURRED WITH
EARLIER 65 KNOT 850 MB WIND MAX THAT PUSHED THROUGH. MODELS SHOW A
LULL IN LOW LEVEL JET THEN A NEW NARROW SURGED SHOWN JUST AHEAD OF
THE FRONT LATER THIS MORNING INTO THIS AFTERNOON. GFS SHOWS UP TO
80 KNOTS AT 850 MB OVER SHEBOYGAN BY LATE AFTERNOON. WITH MEAN WIND
IN SURFACE TO 850 MB LAYER OF NEARLY 60 KNOTS...CERTAINLY CONCERN
FOR STRONG WIND GUSTS SO WILL GO WITH WIND ADVISORY FOR THE CENTRAL
AND EASTERN PORTIONS OF THE CWA. HRRR SURFACE GUST POTENTIAL
INDICATES 40 KNOTS AND GFS BUFKIT SHOWING SIMILAR GUST POTENTIAL
ESPECIALLY TOWARD THE LAKE SHORE.
RAIN SHOULD SPREAD EAST ALONG WITH A FEW RUMBLES OF THUNDER AND MAY
NOT QUITE REACH LAKE SHORE BY 00Z.
TONIGHT-FORECAST CONFIDENCE HIGH
CONTINUED CRASHING OF UPPER HEIGHTS AS FULL LATITUDE TROUGH CRASHES
THROUGH THE MISSISSIPPI RIVER VALLEY. 500 MB 12 HOUR FALLS OF 180
METERS SPREAD ACROSS SOUTHERN WISCONSIN...HELPING USHER IN MUCH
COLDER AIR.
WINDS SHOULD DIE DOWN BEHIND COLD FRONT SO WILL LET WIND ADVISORY
EXPIRE IN THE WESTERN AREAS AT 00Z AND 02Z IN THE EAST PER
COORDINATION WITH DVN AND LOT WFOS.
RAIN SHOULD END PRIOR TO AIR COOLING ENOUGH FOR CHANGE OVER TO
SNOW. HOWEVER...HAVE A CHANCE OF LIGHT SNOW AT THE TAIL END OF THE
PRECIPITATION BUT GUT FEELING IS THAT PROBABLY IS PRETTY LOW.
ALMOST ALL OF THE GUIDANCE SHOWS THE PRECIP CUTTING OFF RIGHT ABOUT
THE TIME THAT THE 850 MB TEMPERATURE CRASHES TO ZERO OR COLDER.
TREMENDOUS COLD ADVECTION SHOULD DROP WESTERN AREAS INTO THE LOWER
20S BY MORNING DESPITE CLOUD COVER WITH CONSENSUS 850 MB TEMPS DOWN
TO -10C BY 12Z MONDAY.
MONDAY THROUGH MONDAY NIGHT...FORECAST CONFIDENCE MEDIUM.
IT WILL BE A COLD...DRY AND MOSTLY CLOUDY MONDAY. EXPECT CLEARING
BEHIND THE FRONT TO LAST INTO MONDAY MORNING AND THEN INSTABILITY
CLOUDS WITH THE STEEP LOW LEVEL LAPSE RATES IN THE CYCLONIC FLOW
REGIME WILL QUICKLY DEVELOP LATE IN THE MORNING. FLURRIES ARE
POSSIBLE WITH THE AFTERNOON LOW CLOUDS. WINDS WILL BE BRISK OUT OF
THE WEST 15 TO 20 MPH WITH HIGHER GUSTS. MAX TEMPS WILL WILL BE IN
THE LOWER 30S...WITH A FEW LOCATIONS EXPECTED TO STAY BELOW FREEZING.
LINGERING TIGHT PRESSURE GRADIENT ABOVE THE SURFACE WILL ONLY ALLOW
FOR A WEAK INVERSION...THUS KEEPING MIN TEMPS IN CHECK. WITH 925MB
TEMPS AROUND -4C...EXPECT LOWS IN THE LOWER 20S. A FEW LOCATIONS MAY
SEE LOWS IN THE TEENS.
TUESDAY THROUGH THURSDAY...FORECAST CONFIDENCE IS MEDIUM TO HIGH.
HIGH PRESSURE WILL RETURN AND BRING DRY WEATHER FOR MUCH OF THE
REMAINDER OF THIS WEEK. 500MB PATTERN WILL BECOME ZONAL OVER THE
NORTHERN PLAINS AND UPPER GREAT LAKES. A SMALL RIPPLE IN THE FLOW
MAY BRING LIGHT RAIN TO WI TUE NIGHT/WED...BUT IT LOOKS LIKE IT JUST
MIGHT BE INCREASING CLOUDS WITH ISENTROPIC LIFT/WARM AIR ADVECTION.
THE LOW LEVELS ARE EXPECTED TO BE TOO DRY TOO ALLOW FOR ANY
MEASURABLE PRECIP. DRY FORECAST FOR SOUTHERN WI CONTINUES.
TEMPS WILL GRADUALLY WARM THROUGH THE WEEK...BEGINNING AROUND 40 ON
TUESDAY AND ENDING UP AROUND 50 FOR THE WEEKEND.
LONG TERM...
NEXT WEEKEND...FORECAST CONFIDENCE MEDIUM.
MODELS TRENDED AWAY FROM PRECIP CHANCES IN SOUTHERN WISCONSIN OVER
THE WEEKEND. IT LOOKS LIKE BLOCKING HIGH PRESSURE WILL BE IN CONTROL
WITH DRY WEATHER THROUGH EARLY NEXT WEEK. MAX TEMPS WILL BE AROUND
50.
AVIATION/12Z TAFS/...
LOW LEVEL SHEAR EARLY THIS MORNING WITH 55 KNOTS AT 2000 FEET AGL
SHOULD RELAX AS SURFACE WINDS INCREASE.
GUSTY SOUTH WINDS TO 35 OR 40 KNOTS EXPECTED ESPECIALLY AT KMKE AND
KENW THIS AFTERNOON AND EARLY EVENING AHEAD OF STRONG COLD FRONT.
PERIOD OF IFR CEILINGS AND VISIBILITIES IN MODERATE TO BRIEFLY HEAVY
RAIN AND RUMBLE OF THUNDER EXPECTED JUST BEHIND COLD FRONT THIS
AFTERNOON IN KMSN AND IN SOUTHEAST TAF SITES LATE AFTERNOON AND
EVENING.
WINDS SHIFT TO WEST AND DIMINISH RAPIDLY BEHIND COLD FRONT THIS
EVENING. CEILINGS SHOULD IMPROVE TO MVFR AFTER RAIN ENDS DURING THE
EVENING AND THEN EVENTUALLY TO VFR AFTER MIDNIGHT AS COLDER AND
DRIER AIR MOVES IN.
NOT IMPOSSIBLE FOR RAIN TO END AS BRIEF PERIOD OF WET SNOW OR SLEET
AT KMSN DURING THE EVENING...BUT NOT MUCH IMPACT EXPECTED WITH
SLIGHTLY ABOVE FREEZING TEMPERATURES.
MARINE...
ALREADY GUSTING NEAR GALE FORCE EARLY THIS MORNING AT KENOSHA HARBOR
AND EXPECT GALE FORCE SOUTHERLY GUSTS LATER THIS MORNING AND THIS
AFTERNOON AHEAD OF STRONG COLD FRONT. THUS GALE WARNING FOR MID
MORNING INTO THE EVENING LOOKS GOOD.
WINDS SHIFT TO WEST AND DIMINISH RAPIDLY AFTER COLD FRONTAL PASSAGE
THIS EVENING. DUE TO HIGH WAVES AND BRISK WEST WINDS...WILL LIKELY
NEED TO DOWNGRADE GALE TO SMALL CRAFT ADVISORY THIS EVENING AND RUN
IT THROUGH MONDAY. WAVES WILL DIMINISH WITH OFFSHORE FLOW BUT
WESTERLY GUSTS TO 25 KNOTS EXPECTED DUE TO UNSTABLE CONDITIONS WITH
STRONG COLD ADVECTION CONTINUING BEHIND FRONT LATE TONIGHT AND
MONDAY.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR WIZ051-057-058-063-
064-068-069.
WIND ADVISORY UNTIL 8 PM CST THIS EVENING FOR WIZ052-059-060-065-
066-070>072.
LM...GALE WARNING UNTIL 9 PM CST THIS EVENING FOR LMZ643>646.
&&
$$
UPDATE...ET/WOOD
TODAY/TONIGHT AND AVIATION/MARINE...CRAVEN
MONDAY THROUGH SATURDAY...MRC