Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 10/16/12
AREA FORECAST DISCUSSION
NWS TAUNTON MA
730 AM EDT SUN OCT 14 2012
.SYNOPSIS...
A WARM FRONT WILL LIFT NORTH ACROSS THE REGION THIS MORNING AND
WILL BE FOLLOWED BY BREEZY AND WARMER WEATHER LASTING INTO
MONDAY. A COLD FRONT WILL MOVE THROUGH MONDAY NIGHT FOLLOWED BY
MAINLY DRY AND MILD WEATHER TUESDAY THROUGH THURSDAY. MOISTURE
WILL INCREASE ALONG WITH SHOWERS POSSIBILITIES BY FRIDAY AND
SATURDAY AS A WEATHER SYSTEM APPROACHES FROM THE WEST.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED FORECAST TO ACCOUNT FOR CURRENT CONDITIONS. MODELS ARE
STRUGGLING WITH TEMPS IN THE NEAR TERMS. SEEMS THAT THE HRRR HAS
THE BEST HANDLE SO FAR. WARM FRONT IS CURRENTLY LIFTING
NORTHWARD...OVER THE SOUTH COAST AND ISLANDS RIGHT NOW. MAIN SWATH
OF PRECIP CONTINUES TO STREAM ACROSS THE REGION. HEAVIER AMOUNTS
HAVE OCCURRED ACROSS NH AND NORTHERN MASSACHUSETTS. EXPECT TREND TO
CONTINUE AND THINGS IMPROVING FROM SOUTHWEST TO NORTHEAST BY MID-
DAY.
PREV DISCUSSION...
INITIAL BATCH OF SHOWERS WHICH ARE MOVING THROUGH N ZONES ARE VERY
LIGHT WITH PRECIP AMOUNTS A TRACE TO A FEW HUNDREDTHS OF AN INCH.
HEAVIER SHOWERS WILL MOVE INTO THE REGION FROM NEW YORK THROUGH
MID MORNING. THE SHOWERS WILL BE CONCENTRATED N OF THE MASS PIKE
THIS MORNING WHERE BEST MOISTURE TRANSPORT AND MID LEVEL OMEGA IS
FOCUSED AHEAD OF THE WARM FRONT. MOISTURE AND LIFT DECREASES
SOUTHWARD TOWARD THE S COAST WHERE COVERAGE OF ANY SHOWERS WILL BE
LIMITED. POPS RANGE FROM CATEGORICAL N OF THE PIKE TO SLIGHT CHC
OVER THE ISLANDS. SHOWERS WILL LIFT N OF THE REGION BY THE
AFTERNOON AS DRY SLOT MOVES IN WITH PARTIAL SUNSHINE DEVELOPING S
OF THE PIKE DURING THE AFTERNOON...BUT MOCLDY SKIES FURTHER N.
IT WILL BE A WINDY DAY...ESPECIALLY IN THE COASTAL PLAIN AS 40 KT
LOW LEVEL JET MOVES ACROSS THE REGION. FAVORABLE LOW LEVEL LAPSE
RATES FROM SFC TO 925 MB WILL PROMOTE ENOUGH MIXING TO SUPPORT GUSTS
TO 30-35 KT...STRONGEST OVER THE CAPE/ISLANDS.
THE GUSTY SW WINDS WILL ADVECT MILDER AIR INTO THE REGION...BUT
PROBABLY NOT TO THE EXTENT THE NAM IS SUGGESTING. LEANED TOWARD
COOLER GFS/ECMWF WITH MAXES RANGING FROM MID/UPPER 50S FAR NORTH
TO MID 60S SOUTH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
TONIGHT...
A DRY AND MILD NIGHT EXPECTED AS REGION WILL REMAIN IN WARM SECTOR
AIRMASS AND FAR ENOUGH REMOVED FROM APPROACHING MOISTURE WITH THE
COLD FRONT TO THE WEST. AREAS OF STRATUS AND PATCHY FOG MAY
DEVELOP OVERNIGHT AS HIGHER DEWPOINT AIR ADVECTS NWD INTO REGION. IT
WILL BE UNSEASONABLY MILD WITH MINS MAINLY IN THE 50S AND CLOSE
TO 60 NEAR THE COAST.
MONDAY...
SHARP MID LEVEL TROF MOVES THROUGH THE GT LAKES WITH THE COLD
FRONT APPROACHING FROM THE WEST. A FEW SHOWERS ARE
POSSIBLE...MAINLY IN THE AFTERNOON AS MOISTURE AXIS AND DECREASING
STABILITY ALOFT MOVE INTO SNE...BUT BETTER CHANCE WILL LIKELY BE
MON NIGHT. WE WILL HAVE CHC POPS. DESPITE MOCLDY SKIES...IT WILL
BE A WARM AND HUMID DAY. 2M TEMPS SUPPORT MAXES IN THE UPPER 60S
TO LOWER 70S AND DEWPOINTS WILL INCREASE TO THE UPPER 50S AND
LOWER 60S WITH MID 60S DEWPOINTS POSSIBLE NEAR THE S COAST.
ANOTHER BREEZY DAY LIKELY IN THE COASTAL PLAIN WITH GUSTS TO 25
KT.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...
* SHOWERY WX RETURNS AS A COLD FRONT MOVE THROUGH MONDAY NIGHT.
* HIGH PRESSURE FOR MID-WEEK WITH MODERATING TEMPS.
* ANOTHER CHANCE FOR SHOWERS LATE FRIDAY INTO THE WEEKEND.
DETAILS...
MODELS/PATTERN...
00Z GUIDANCE IS IN FAIRLY GOOD AGREEMENT FOR THE FORECAST. SO HAVE
MODERATE TO HIGH CONFIDENCE IN THE FORECAST UP TIL LATE IN THE WORK
WEEK...THEN CONFIDENCE DECREASES AS MODEL SPREAD INCREASES. UPPER
LEVEL TROUGH WILL MOVE THROUGH THE AREA ON MONDAY...WITH THE GFS
BEING MORE AMPLIFIED WHILE THE NAM IS VERY PROGRESSIVE. THE SYSTEM
WILL MOVE OUT OF THE REGION BY LATE TUESDAY ALLOWING FOR HIGH
PRESSURE TO BUILD IN FOR THE MID-WEEK. BULK OF THE FORECAST WAS A
MODEL BLEND...MINUS HPC AS THEY WASHED OUT A LOT OF MESO FEATURES.
MODELS ARE SHOWING A POSSIBLE CUT-OFF LOW DEVELOPING OVER THE UPPER
MISSISSIPPI VALLEY. THE ECMWF HAS BEEN MORE AMPLIFIED WITH THIS LOW
THEN THE GFS. REGARDLESS THE PLACEMENT OF THE LOW WILL HAVE AN BIG
IMPACT ON THE REGIONS WEATHER. KEPT PREV FORECAST FOR THURSDAY
ONWARD WITH A LITTLE BLEND OF THE LATEST ECMWF.
MONDAY NIGHT...HIGH CONFIDENCE.
COLD FRONT WILL PUSH THROUGH THE REGION ON MONDAY NIGHT. COMBINED
WITH A SHORTWAVE FORMING A SURFACE LOW ALONG THE FRONT...EXPECT
SHOWERS TO MOVE ACROSS THE REGION WITH AN ENHANCE AREA OF PRECIP
ACROSS RI AND EASTERN MASS. PWAT VALUES RANGE FROM 1 TO 1.5 INCHES
AND SINCE THE SYSTEM IS MOVING QUICKLY BELIEVE THE THREAT FOR
FLOODING IS MINIMAL. HOWEVER WITHIN STRONGER STORMS THERE MAY BE
POSSIBLE MINOR URBAN FLOODING. FRONT SHOULD MOVE OFFSHORE BY LATE
TUESDAY MORNING.
MID-WEEK...MODERATE CONFIDENCE
A FEW LINGER SHOWERS MAY STILL EXIST ACROSS THE CAPE AND ISLANDS IN
THE MORNING. OTHERWISE EXPECT A DRY ON TUESDAY. BACKSIDE OF THE LOW
WILL BRING SOME CLOUD COVER TO THE REGION...BUT ATMOSPHERE IS TO DRY
FOR PRECIP TO FORM. BEHIND THE FRONT ON TUESDAY...WINDS WILL SWITCH
TO THE WEST AND GUST DURING THE DAY. BELIEVE MODELS ARE STILL
UNDERESTIMATING THE MIXING POTENTIAL...ESP ACROSS THE WATERS. EXPECT
GUSTS TO BE AROUND 25 MPH DURING THE DAY.
EXPECT UPPER LEVEL RIDGE TO WORK ITS WAY INTO THE AREA BY LATE
TUESDAY AFTERNOON AS HIGH PRESSURE WILL DOMINATE AT THE SURFACE.
TEMPS DURING THIS TIMEFRAME WILL INCREASE SLIGHTLY WITH MAXS ON
TUESDAY IN THE UPPER 50S TO LOW 60S INCREASING TO MID 60S TO UPPER
70S BY THURSDAY. DRY WEATHER SHOULD PREVAIL DURING THE MID-WEEK AS
THERE IS STILL A GOOD AMOUNT OF DRY AIR... ALLOWING FOR PLEASANT
FALL-LIKE WEATHER.
FRIDAY AND BEYOND...LOW CONFIDENCE
HUGE DIFFERENCE IN THE MODELS HAVE LEAD TO LOW CONFIDENCE FOR THE
END OF THE WEEK INTO THE WEEKEND. AS STATED EARLIER CUT-OFF LOW WILL
FORM ACROSS THE UPPER MISSISSIPPI VALLEY. THE 13.00Z ECMWF ONCE THE
FIRST MODEL TO SHOW THIS FEATURE AS THE 13.12Z GFS JUMPED ON BOARD.
CURRENTLY A LARGE PLACEMENT ON THE LOWS LOCATION. TRENDED TOWARDS
THE ECMWF AS WELL AS PREV FORECAST AS THERE IS STILL A LOT OF
UNCERTAINTY.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT
MODERATE...30 PERCENT TO 60 PERCENT
HIGH...GREATER THAN 60 PERCENT
OVERVIEW...MODERATE CONFIDENCE.
SHOWERS OVERSPREADING THE REGION EARLY THIS MORNING AND CONDITIONS
WILL LOWER TO MVFR AND POSSBILY IFR... ESPECIALLY N OF THE MASS
PIKE. S OF THE PIKE JUST BRIEF MVFR IS EXPECTED WITH MAINLY VFR
NEAR THE S COAST. CONDITIONS WILL GRADUALLY IMPROVE AND BECOME VFR
IN THE AFTERNOON AS THE SHOWERS LIFT TO THE N. BECOMING WINDY IN
THE COASTAL PLAIN AND S COAST WITH SW WIND GUSTS TO 30 KT TODAY.
CONDITIONS LOWERING TO MVFR/IFR LATER SUN NIGHT AS STRATUS AND
PATCHY FOG DEVELOPS...IMPROVING TO VFR DURING MONDAY BUT AREAS OF
MVFR MAY REDEVELOP IN THE AFTERNOON WITH MORE SHOWERS POSSIBLE.
KBOS TAF...MODERATE CONFIDENCE.
A PERIOD OF MVFR IN SHOWERS IS LIKELY LATER THIS MORNING...THEN
IMPROVING TO VFR THIS AFTERNOON. SW GUSTS TO 25 KT LIKELY TODAY.
STRATUS MAY DEVELOP LATE TONIGHT.
KBDL TAF...MODERATE CONFIDENCE.
BRIEF PERIOD OF MVFR AND A FEW SHOWERS POSSIBLE THIS
MORNING...OTHERWISE MAINLY VFR. SW GUSTS TO 20-25 KT DEVELOPING.
MVFR/IFR STRATUS MAY DEVELOP LATE TONIGHT.
OUTLOOK...MONDAY NIGHT THROUGH THURSDAY...
MONDAY NIGHT...
MODERATE CONFIDENCE IN VFR WITH MVFR IN HEAVIER SHOWERS...ESP ACROSS
RI AND EASTERN MASS. SHOULD IMPROVE WEST TO EAST BY EARLY TUESDAY
MORNING.
TUESDAY TROUGH THURSDAY...
HIGH CONFIDENCE IN VFR CONDITIONS THROUGH THURSDAY AS HIGH PRESSURE
WILL PREVAIL.
&&
.MARINE...
SHORT TERM...HIGH CONFIDENCE.
LOW LEVEL JET WILL SUPPORT SW WIND GUSTS TO 30 KT TODAY ACROSS THE
WATERS AS THERE IS DECENT LOW LEVEL MIXING. A FEW GALE FORCE GUSTS
TO 35 KT ARE POSSIBLE...ESPECIALLY OVER S COASTAL WATERS BUT HELD
OFF ON GALE WARNING FOR NOW AS WE DONT THINK IT WILL BE
WIDESPREAD. WINDS DIMINISH SLIGHTLY TONIGHT BUT SCA GUSTS TO 25
KT WILL LIKELY CONTINUE INTO MONDAY.
OUTLOOK...MONDAY NIGHT THROUGH THURSDAY...
MODERATE CONFIDENCE.
COLD FRONT WILL MOVE THROUGH MONDAY NIGHT INTO EARLY TUESDAY MORNING
KEEPING OUTER WATER SEAS UP IN SCA CRITERIA. EXPECT WESTERLY WINDS
BEHIND THE FRONT TO GUST UP TO 25-30KTS DURING THE DAY ON TUESDAY. HIGH
PRESSURE WILL BUILD ACROSS THE WATERS LATE TUESDAY LASTING INTO
THURSDAY. STRONG SOUTHERN SWELL FROM RAFAEL MAY REACH THE WATERS BY
LATE WEDNESDAY INCREASING SEAS TO 6 TO 8 FT. EXPECT CONDITIONS TO
SLOWLY RELAX BY LATE THURSDAY.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 PM EDT MONDAY FOR ANZ232>235-237-
250-254>256.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ230.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT MONDAY FOR ANZ231-251.
SMALL CRAFT ADVISORY UNTIL 9 PM EDT THIS EVENING FOR ANZ236.
&&
$$
SYNOPSIS...KJC/DUNTEN
NEAR TERM...KJC/DUNTEN
SHORT TERM...KJC
LONG TERM...DUNTEN
AVIATION...KJC/DUNTEN
MARINE...KJC/DUNTEN
AREA FORECAST DISCUSSION
NWS MIAMI FL
154 PM EDT SUN OCT 14 2012
.AVIATION...
ISOLATED TO WIDELY SCATTERED RAIN SHOWERS CONTINUE TO PUSH WEST
ACROSS THE SOUTH FLORIDA PENINSULA THIS AFTERNOON AND INTO THE
EARLY EVENING HOURS DUE TO DECENT LOW LEVEL MOISTURE AND WEAK 700
MB DIVERGENCE. LATEST SHORT TERM GUIDANCE KEEPS MOST OF THE
PRECIPITATION ACROSS THE ATLANTIC AND GULF COASTAL WATERS THROUGH
THE LATE EVENING AND OVERNIGHT HOURS. KEPT VCSH MENTION OUT OF ALL
EAST COAST TAFS AFTER 00Z. GUSTY EAST-NORTHEASTERLY WINDS WILL
ALSO BEGIN TO DECREASE DURING THE EARLY MORNING HOURS TOMORROW.
OTHERWISE...VFR CONDITIONS SHOULD PREVAIL THROUGH THE PERIOD.
&&
.PREV DISCUSSION... /ISSUED 735 AM EDT SUN OCT 14 2012/
AVIATION...
STRONG NORTHEAST FLOW ACROSS THE ATLANTIC WILL CONTINUE
THIS MORNING INTO THIS AFTERNOON. STRATOCUMULUS IN THE 3 KFT TO 6
KFT RANGE WITH EMBEDDED SHOWERS WILL CONTINUE TO STREAM SOUTHWEST
ACROSS THE ATLANTIC WATERS THIS MORNING WITH THE EAST COAST TAF
SITES EXPERIENCING BRIEF PASSING SHOWERS FROM TIME TO TIME. BY THE
AFTERNOON SCATTERED SHOWERS ARE POSSIBLE WITH A SLIGHT CHANCE OF
THUNDERSTORMS BUT CONFIDENCE IS LOW WITH THE THUNDERSTORMS WITH
VCSH ASSIGNED TO ALL TERMINALS. THE STRONG NORTHEAST WINDS ARE
EXPECTED TO START DECREASING SLOWLY AROUND 00Z THIS EVENING.
PREV DISCUSSION... /ISSUED 415 AM EDT SUN OCT 14 2012/
.HIGH RISK OF RIP CURRENTS ATLANTIC BEACHES/MINOR COASTAL
FLOODING POSSIBLE BEFORE WINDS RELAX THROUGHOUT THE DAY...
DISCUSSION...THE PWAT ON THE MIAMI EVENING SOUNDING YESTERDAY WAS
ONLY 1.12 INCHES, BUT IT IS PROGGED TO INCREASE INTO THE 1.4-1.6
RANGE THIS AFTERNOON THROUGH MONDAY, BEFORE DRIER AIR INFILTRATES
SOUTH FL BEHIND A WEAK COLD FRONT MON NIGHT. THE RESULT IS THE
EXPECTATION OF SCATTERED SHOWERS, AND POSSIBLY A TSTORM OR TWO,
TODAY-MONDAY WITH THE FOCUS ALONG THE ATLANTIC COAST. THEN, AS A
DRIER AIRMASS ADVECTS INTO THE AREA MON NIGHT-TUE, LITTLE SHOWER
ACTIVITY IS EXPECTED. HOWEVER, WILL PLACE SLIGHT CHANCE EASTERN
HALF OF THE AREA AS THERE COULD BE JUST ENOUGH LOW LEVEL MOISTURE
TO SQUEEZE OUT A FEW SHOWERS ON A QUICK RETURN TO NE-E FLOW BEHIND
THE WEAK FRONTAL BOUNDARY...AS PER GFS/ECMWF MODEL LOW QPF FIELDS.
INSTABILITY INCREASES JUST SLIGHTLY TODAY-MON BUT STILL WEAK LAPSE
RATES. HOWEVER, CANNOT RULE OUT A TSTORM...AND HRRR SHOWS A COUPLE
OF ECHO TOPS TO 40KFT OVER THE SOUTHERN ATLANTIC AND SOUTHERN
INTERIOR OF SOUTH FL THIS AFTERNOON...SO WILL INCLUDE SLIGHT
CHANCE OF TSTORMS TODAY AND MONDAY.
A HIGH RISK OF RIP CURRENTS CONTINUES ALONG THE ATLANTIC BEACHES
TODAY. WINDS WILL GRADUALLY SUBSIDE, BUT THE HIGH RISK WILL PERSIST
THROUGH THE EVENING. MINOR COASTAL FLOODING WILL BE POSSIBLE,
ESPECIALLY AROUND HIGH TIDE AT AROUND SUNRISE THIS MORNING DUE TO
TIDES RUNNING ABOUT A HALF A FOOT ABOVE PREDICTED DUE TO THE STRONG
ONSHORE FLOW. SO WILL CONTINUE TO ADVERTISE THIS POTENTIAL.
SUBSIDING ONSHORE WINDS ALONG THE ATLANTIC COAST SHOULD SLIGHTLY
REDUCE THIS POTENTIAL INTO THE EARLY WORK WEEK, DESPITE TIDES
REMAINING HIGH DUE TO THE SPRING TIDE.
AGAIN, BEHIND THE FRONTAL PASSAGE MON NIGHT, A DRIER AIRMASS WILL
MOVE IN WITH RE-ENFORCING LOWER DEWPOINTS IN THE 60S AND JUST SLIGHT
RAIN CHANCES. A FEW SHOWERS WILL CONTINUE POSSIBLE ESPECIALLY
INTERIOR/EAST COAST THROUGH LATE WEEK. THEN ANOTHER STRONGER COLD
FRONT APPROACHES NEXT WEEKEND...AND MAY MOVE THROUGH, ALTHOUGH THE
LATEST GFS/ECMWF SHOW MUCH OF THE ENERGY NORTH OF OUR AREA. IN
OTHER WORDS, THEY`VE TRENDED LESS AGGRESSIVE WITH THE
FRONT, ESPECIALLY THE ECMWF MODEL. STILL, THERE LOOKS TO BE
ANOTHER COLD FRONTAL PASSAGE SOMETIME THIS WEEKEND. GIVEN TIMING
UNCERTAINTIES, MAINTAINED SLIGHT CHANCE OF SHOWERS THROUGH NEXT
WEEKEND. THE ECMWF SHOWS THE CLOSED MID/UPPER LOW A BIT FURTHER
SOUTH, PULLING UP HIGHER MOISTURE AND EVEN A POTENTIAL FOR TSTORMS
AHEAD/ALONG THE FRONT SATURDAY. WE CAN WATCH MODEL TRENDS. A LOT
OF UNCERTAINTY THIS FAR OUT.
MARINE...WILL CONTINUE THE SMALL CRAFT ADVISORY FOR THE OFFSHORE
GULF WATERS AND BISCAYNE BAY THIS MORNING, BUT DROPPED THE LAKE AS
OBS ARE BELOW 20 KT. THE SCA WILL CONTINUE FOR THE ATLANTIC TODAY,
AND THE PALM BEACH WATERS THROUGH 6Z TONIGHT DUE TO SEAS OF 7 FT
THROUGH THEN BEFORE SUBSIDING FURTHER AS WINDS CONTINUE TO RELAX
THROUGH THE DAY AND BEYOND.
FIRE WEATHER...NO CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 77 87 75 86 / 20 30 10 20
FORT LAUDERDALE 79 87 76 88 / 20 30 10 20
MIAMI 78 87 75 87 / 20 30 10 20
NAPLES 74 89 72 85 / 20 20 10 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR COASTAL
BROWARD-COASTAL MIAMI DADE-COASTAL PALM BEACH.
AM...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR COASTAL
WATERS FROM DEERFIELD BEACH TO OCEAN REEF, FL OUT 20 NM-
WATERS FROM DEERFIELD BEACH TO OCEAN REEF, FL EXTENDING
FROM 20 NM TO THE TERRITORIAL WATERS OF THE BAHAMAS.
SMALL CRAFT ADVISORY UNTIL 2 AM EDT MONDAY FOR COASTAL WATERS
FROM JUPITER INLET TO DEERFIELD BEACH, FL OUT 20 NM-WATERS
FROM JUPITER INLET TO DEERFIELD BEACH, FL EXTENDING FROM 20
NM TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR BISCAYNE
BAY.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...85/AG
AVIATION/RADAR...10/CD
AREA FORECAST DISCUSSION
NWS MIAMI FL
735 AM EDT SUN OCT 14 2012
.AVIATION...
STRONG NORTHEAST FLOW ACROSS THE ATLANTIC WILL CONTINUE
THIS MORNING INTO THIS AFTERNOON. STRATOCUMULUS IN THE 3 KFT TO 6
KFT RANGE WITH EMBEDDED SHOWERS WILL CONTINUE TO STREAM SOUTHWEST
ACROSS THE ATLANTIC WATERS THIS MORNING WITH THE EAST COAST TAF
SITES EXPERIENCING BRIEF PASSING SHOWERS FROM TIME TO TIME. BY THE
AFTERNOON SCATTERED SHOWERS ARE POSSIBLE WITH A SLIGHT CHANCE OF
THUNDERSTORMS BUT CONFIDENCE IS LOW WITH THE THUNDERSTORMS WITH
VCSH ASSIGNED TO ALL TERMINALS. THE STRONG NORTHEAST WINDS ARE
EXPECTED TO START DECREASING SLOWLY AROUND 00Z THIS EVENING.
&&
.PREV DISCUSSION... /ISSUED 415 AM EDT SUN OCT 14 2012/
..HIGH RISK OF RIP CURRENTS ATLANTIC BEACHES/MINOR COASTAL
FLOODING POSSIBLE BEFORE WINDS RELAX THROUGHOUT THE DAY...
DISCUSSION...THE PWAT ON THE MIAMI EVENING SOUNDING YESTERDAY WAS
ONLY 1.12 INCHES, BUT IT IS PROGGED TO INCREASE INTO THE 1.4-1.6
RANGE THIS AFTERNOON THROUGH MONDAY, BEFORE DRIER AIR INFILTRATES
SOUTH FL BEHIND A WEAK COLD FRONT MON NIGHT. THE RESULT IS THE
EXPECTATION OF SCATTERED SHOWERS, AND POSSIBLY A TSTORM OR TWO,
TODAY-MONDAY WITH THE FOCUS ALONG THE ATLANTIC COAST. THEN, AS A
DRIER AIRMASS ADVECTS INTO THE AREA MON NIGHT-TUE, LITTLE SHOWER
ACTIVITY IS EXPECTED. HOWEVER, WILL PLACE SLIGHT CHANCE EASTERN
HALF OF THE AREA AS THERE COULD BE JUST ENOUGH LOW LEVEL MOISTURE
TO SQUEEZE OUT A FEW SHOWERS ON A QUICK RETURN TO NE-E FLOW BEHIND
THE WEAK FRONTAL BOUNDARY...AS PER GFS/ECMWF MODEL LOW QPF FIELDS.
INSTABILITY INCREASES JUST SLIGHTLY TODAY-MON BUT STILL WEAK LAPSE
RATES. HOWEVER, CANNOT RULE OUT A TSTORM...AND HRRR SHOWS A COUPLE
OF ECHO TOPS TO 40KFT OVER THE SOUTHERN ATLANTIC AND SOUTHERN
INTERIOR OF SOUTH FL THIS AFTERNOON...SO WILL INCLUDE SLIGHT
CHANCE OF TSTORMS TODAY AND MONDAY.
A HIGH RISK OF RIP CURRENTS CONTINUES ALONG THE ATLANTIC BEACHES
TODAY. WINDS WILL GRADUALLY SUBSIDE, BUT THE HIGH RISK WILL PERSIST
THROUGH THE EVENING. MINOR COASTAL FLOODING WILL BE POSSIBLE,
ESPECIALLY AROUND HIGH TIDE AT AROUND SUNRISE THIS MORNING DUE TO
TIDES RUNNING ABOUT A HALF A FOOT ABOVE PREDICTED DUE TO THE STRONG
ONSHORE FLOW. SO WILL CONTINUE TO ADVERTISE THIS POTENTIAL.
SUBSIDING ONSHORE WINDS ALONG THE ATLANTIC COAST SHOULD SLIGHTLY
REDUCE THIS POTENTIAL INTO THE EARLY WORK WEEK, DESPITE TIDES
REMAINING HIGH DUE TO THE SPRING TIDE.
AGAIN, BEHIND THE FRONTAL PASSAGE MON NIGHT, A DRIER AIRMASS WILL
MOVE IN WITH RE-ENFORCING LOWER DEWPOINTS IN THE 60S AND JUST SLIGHT
RAIN CHANCES. A FEW SHOWERS WILL CONTINUE POSSIBLE ESPECIALLY
INTERIOR/EAST COAST THROUGH LATE WEEK. THEN ANOTHER STRONGER COLD
FRONT APPROACHES NEXT WEEKEND...AND MAY MOVE THROUGH, ALTHOUGH THE
LATEST GFS/ECMWF SHOW MUCH OF THE ENERGY NORTH OF OUR AREA. IN
OTHER WORDS, THEY`VE TRENDED LESS AGGRESSIVE WITH THE
FRONT, ESPECIALLY THE ECMWF MODEL. STILL, THERE LOOKS TO BE
ANOTHER COLD FRONTAL PASSAGE SOMETIME THIS WEEKEND. GIVEN TIMING
UNCERTAINTIES, MAINTAINED SLIGHT CHANCE OF SHOWERS THROUGH NEXT
WEEKEND. THE ECMWF SHOWS THE CLOSED MID/UPPER LOW A BIT FURTHER
SOUTH, PULLING UP HIGHER MOISTURE AND EVEN A POTENTIAL FOR TSTORMS
AHEAD/ALONG THE FRONT SATURDAY. WE CAN WATCH MODEL TRENDS. A LOT
OF UNCERTAINTY THIS FAR OUT.
MARINE...WILL CONTINUE THE SMALL CRAFT ADVISORY FOR THE OFFSHORE
GULF WATERS AND BISCAYNE BAY THIS MORNING, BUT DROPPED THE LAKE AS
OBS ARE BELOW 20 KT. THE SCA WILL CONTINUE FOR THE ATLANTIC TODAY,
AND THE PALM BEACH WATERS THROUGH 6Z TONIGHT DUE TO SEAS OF 7 FT
THROUGH THEN BEFORE SUBSIDING FURTHER AS WINDS CONTINUE TO RELAX
THROUGH THE DAY AND BEYOND.
FIRE WEATHER...NO CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 87 76 88 73 / 40 30 30 10
FORT LAUDERDALE 88 79 88 75 / 40 30 30 10
MIAMI 88 78 88 75 / 40 30 30 10
NAPLES 91 73 89 72 / 30 10 20 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK THROUGH THIS EVENING FOR COASTAL BROWARD-
COASTAL MIAMI DADE-COASTAL PALM BEACH.
AM...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR COASTAL
WATERS FROM DEERFIELD BEACH TO OCEAN REEF, FL OUT 20 NM-
WATERS FROM DEERFIELD BEACH TO OCEAN REEF, FL EXTENDING
FROM 20 NM TO THE TERRITORIAL WATERS OF THE BAHAMAS.
SMALL CRAFT ADVISORY UNTIL 2 AM EDT MONDAY FOR COASTAL WATERS
FROM JUPITER INLET TO DEERFIELD BEACH, FL OUT 20 NM-WATERS
FROM JUPITER INLET TO DEERFIELD BEACH, FL EXTENDING FROM 20
NM TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR BISCAYNE
BAY.
GM...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR GULF
WATERS FROM CHOKOLOSKEE TO BONITA BEACH, FL EXTENDING FROM
20 TO 60 NM.
&&
$$
DISCUSSION/MARINE/FIRE...57/DG
AVIATION/RADAR...60/BD
AREA FORECAST DISCUSSION
NWS MIAMI FL
415 AM EDT SUN OCT 14 2012
...HIGH RISK OF RIP CURRENTS ATLANTIC BEACHES/MINOR COASTAL
FLOODING POSSIBLE BEFORE WINDS RELAX THROUGHOUT THE DAY...
.DISCUSSION...THE PWAT ON THE MIAMI EVENING SOUNDING YESTERDAY WAS
ONLY 1.12 INCHES, BUT IT IS PROGGED TO INCREASE INTO THE 1.4-1.6
RANGE THIS AFTERNOON THROUGH MONDAY, BEFORE DRIER AIR INFILTRATES
SOUTH FL BEHIND A WEAK COLD FRONT MON NIGHT. THE RESULT IS THE
EXPECTATION OF SCATTERED SHOWERS, AND POSSIBLY A TSTORM OR TWO,
TODAY-MONDAY WITH THE FOCUS ALONG THE ATLANTIC COAST. THEN, AS A
DRIER AIRMASS ADVECTS INTO THE AREA MON NIGHT-TUE, LITTLE SHOWER
ACTIVITY IS EXPECTED. HOWEVER, WILL PLACE SLIGHT CHANCE EASTERN
HALF OF THE AREA AS THERE COULD BE JUST ENOUGH LOW LEVEL MOISTURE
TO SQUEEZE OUT A FEW SHOWERS ON A QUICK RETURN TO NE-E FLOW BEHIND
THE WEAK FRONTAL BOUNDARY...AS PER GFS/ECMWF MODEL LOW QPF FIELDS.
INSTABILITY INCREASES JUST SLIGHTLY TODAY-MON BUT STILL WEAK LAPSE
RATES. HOWEVER, CANNOT RULE OUT A TSTORM...AND HRRR SHOWS A COUPLE
OF ECHO TOPS TO 40KFT OVER THE SOUTHERN ATLANTIC AND SOUTHERN
INTERIOR OF SOUTH FL THIS AFTERNOON...SO WILL INCLUDE SLIGHT
CHANCE OF TSTORMS TODAY AND MONDAY.
A HIGH RISK OF RIP CURRENTS CONTINUES ALONG THE ATLANTIC BEACHES
TODAY. WINDS WILL GRADUALLY SUBSIDE, BUT THE HIGH RISK WILL PERSIST
THROUGH THE EVENING. MINOR COASTAL FLOODING WILL BE POSSIBLE,
ESPECIALLY AROUND HIGH TIDE AT AROUND SUNRISE THIS MORNING DUE TO
TIDES RUNNING ABOUT A HALF A FOOT ABOVE PREDICTED DUE TO THE STRONG
ONSHORE FLOW. SO WILL CONTINUE TO ADVERTISE THIS POTENTIAL.
SUBSIDING ONSHORE WINDS ALONG THE ATLANTIC COAST SHOULD SLIGHTLY
REDUCE THIS POTENTIAL INTO THE EARLY WORK WEEK, DESPITE TIDES
REMAINING HIGH DUE TO THE SPRING TIDE.
AGAIN, BEHIND THE FRONTAL PASSAGE MON NIGHT, A DRIER AIRMASS WILL
MOVE IN WITH RE-ENFORCING LOWER DEWPOINTS IN THE 60S AND JUST SLIGHT
RAIN CHANCES. A FEW SHOWERS WILL CONTINUE POSSIBLE ESPECIALLY
INTERIOR/EAST COAST THROUGH LATE WEEK. THEN ANOTHER STRONGER COLD
FRONT APPROACHES NEXT WEEKEND...AND MAY MOVE THROUGH, ALTHOUGH THE
LATEST GFS/ECMWF SHOW MUCH OF THE ENERGY NORTH OF OUR AREA. IN
OTHER WORDS, THEY`VE TRENDED LESS AGGRESSIVE WITH THE
FRONT, ESPECIALLY THE ECMWF MODEL. STILL, THERE LOOKS TO BE
ANOTHER COLD FRONTAL PASSAGE SOMETIME THIS WEEKEND. GIVEN TIMING
UNCERTAINTIES, MAINTAINED SLIGHT CHANCE OF SHOWERS THROUGH NEXT
WEEKEND. THE ECMWF SHOWS THE CLOSED MID/UPPER LOW A BIT FURTHER
SOUTH, PULLING UP HIGHER MOISTURE AND EVEN A POTENTIAL FOR TSTORMS
AHEAD/ALONG THE FRONT SATURDAY. WE CAN WATCH MODEL TRENDS. A LOT
OF UNCERTAINTY THIS FAR OUT.
&&
.MARINE...WILL CONTINUE THE SMALL CRAFT ADVISORY FOR THE OFFSHORE
GULF WATERS AND BISCAYNE BAY THIS MORNING, BUT DROPPED THE LAKE AS
OBS ARE BELOW 20 KT. THE SCA WILL CONTINUE FOR THE ATLANTIC TODAY,
AND THE PALM BEACH WATERS THROUGH 6Z TONIGHT DUE TO SEAS OF 7 FT
THROUGH THEN BEFORE SUBSIDING FURTHER AS WINDS CONTINUE TO RELAX
THROUGH THE DAY AND BEYOND.
&&
.FIRE WEATHER...NO CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 87 76 88 73 / 40 30 30 10
FORT LAUDERDALE 88 79 88 75 / 40 30 30 10
MIAMI 88 78 88 75 / 40 30 30 10
NAPLES 91 73 89 72 / 30 10 20 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK THROUGH THIS EVENING FOR COASTAL BROWARD-
COASTAL MIAMI DADE-COASTAL PALM BEACH.
AM...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR COASTAL
WATERS FROM DEERFIELD BEACH TO OCEAN REEF, FL OUT 20 NM-
WATERS FROM DEERFIELD BEACH TO OCEAN REEF, FL EXTENDING
FROM 20 NM TO THE TERRITORIAL WATERS OF THE BAHAMAS.
SMALL CRAFT ADVISORY UNTIL 2 AM EDT MONDAY FOR COASTAL WATERS
FROM JUPITER INLET TO DEERFIELD BEACH, FL OUT 20 NM-WATERS
FROM JUPITER INLET TO DEERFIELD BEACH, FL EXTENDING FROM 20
NM TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR BISCAYNE
BAY.
GM...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR GULF
WATERS FROM CHOKOLOSKEE TO BONITA BEACH, FL EXTENDING FROM
20 TO 60 NM.
&&
$$
DISCUSSION/MARINE/FIRE...57/GREGORIA
AVIATION/RADAR...60/BD
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1239 AM EDT SUN OCT 14 2012
.SYNOPSIS...
HIGH PRESSURE WILL WEAKEN ACROSS THE AREA INTO EARLY MONDAY...
THEN GIVE WAY TO A COLD FRONT LATE MONDAY INTO MONDAY NIGHT.
WEAK HIGH PRESSURE WILL THEN PREVAIL THROUGH MID WEEK. ANOTHER
COLD FRONT IS EXPECTED TO APPROACH THE EAST COAST BY NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
ISENTROPIC LIFT IS STRONGEST ACROSS THE SOUTH WHERE IT HAS
MANIFESTED ITSELF INTO A STRATOCUMULUS DECK. EVEN A FEW SHOWERS
HAVE MADE IT ONSHORE ACROSS PARTS OF MCINTOSH AND LIBERTY
COUNTIES. 14/03Z RAP ISENTROPIC FIELDS INDICATE THE STRONGEST
ASSENT WILL REMAIN FOCUSED ACROSS SOUTHEAST GEORGIA FOR THE NEXT
FEW HOURS BEFORE DIMINISHING. MODIFIED POP AND SKY GRIDS TO DENOTE
GOING TRENDS AND TO FOCUS THE GREATEST COVERAGE OF CLOUDS AS WELL AS
ISOLATED SHOWERS ACROSS THE FAR SOUTH. LOWS WILL RANGE FROM THE
LOWER 50S WELL INLAND TO THE UPPER 60S/NEAR 70 AT THE BEACHES.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY/...
SUNDAY...A STRONG SHORT WAVE FOUND MOVING NE FROM THE MID MS VALLEY
TO THE GREAT LAKES WILL CAUSE ITS ASSOCIATED SURFACE LOW PRESSURE TO
DEEPEN AS IT MOVES IN TANDEM NE WITH THE FEATURE ALOFT. THIS IN TURN
WILL FORCE EASTWARD THE NORTHERN PORTION OF HIGH PRESSURE THAT
STRETCHES FROM SOUTH OF NEW ENGLAND TO THE SE STATES. THE ASSOCIATED
RIDGE AXIS WILL HANG BACK TO THE WEST AND SW AND ALIGN ITSELF ACROSS
THE LOCAL CWFA DURING THE LATE MORNING AND AFTERNOON. AS THIS
TRANSPIRES THE LOW LEVEL FLOW WILL VEER AROUND TO THE EAST AND
SE...AND WHEN COMBINED WITH CONSIDERABLE WARM ADVECTION AS 850 MB
TEMPS CLIMB TO 13-14C...WE WILL EXPERIENCE A NOTICEABLY WARMER DAY.
WE WON/T GO AS HIGH AS THE LOW LEVEL THICKNESS FORECAST GIVEN THE
ONSHORE COMPONENT...BUT EVEN SO OUR MAX TEMPS AWAY FROM THE COOLER
COASTLINE WILL STILL REACH THE LOWER 80S. THE WEAK AND NEARBY
COASTAL TROUGH IN THE MORNING WILL DISSIPATE BY AFTERNOON...BUT
ITS CLOSE PROXIMITY AND WEAK ISENTROPIC MIGHT BE ENOUGH TO CAUSE A
FEW MORNING SHOWERS NEAR THE COAST. FOR THAT REASON WE/LL HOLD
ONTO 20 POPS BUT NO MORE SINCE THE MOISTURE DEPTH IS CONFINED TO
ONLY THE FIRST FEW THOUSAND FEET OF THE TROPOSPHERE.
SUNDAY NIGHT...THE INITIAL SHORT WAVE AND ITS SURFACE LOW WILL LIFT
NE INTO CANADA...WHILE ANOTHER STRONG SHORT WAVE DROPS SE AND
AMPLIFIES A TROUGH SOUTH TO THE LOWER MS VALLEY. THIS IN TURN SENDS
A COLD FRONT TOWARD THE APPALACHIAN MOUNTAINS LATE...AS HEIGHT FALLS
ALOFT WEAKENS THE SURFACE RIDGING ACROSS SOUTHERN SC AND SE GA. A
WEAK COASTAL TROUGH WILL TRY AND FORM ONCE THE ANTICYCLONIC FLOW
DIMINISHES ENOUGH...AND WITH A VEERING SYNOPTIC FLOW WE MIGHT SEE A
FEW ATLANTIC SHOWERS MAKE A RUN FOR COASTAL SECTIONS. ONCE AGAIN
THOUGH THE DEPTH OF THE MOISTURE IS LIMITED...SO RAIN CHANCES WILL
BE HELD UNDER 15 PERCENT. PROVIDED THERE IS NOT TOO MUCH CLOUD
COVER FROM OFF ATLANTIC...THERE LOOKS TO BE THE POTENTIAL FOR FOG.
DRY AIR ALOFT ATOP A MOIST BOUNDARY LAYER...LIGHT WIND FIELDS AND
FOG STABILITY INDICES LESS THAN 20 SUGGEST AT LEAST PATCHY FOG
FORMATION. MUCH OF THE VERTICAL WILL WARM AND HOLD TEMPS UP IN THE
LOWER-MIDDLE 60S INLAND FROM US-17 AND THE UPPER 60S TO NEAR 70 AT
THE SHORE.
MONDAY...AN AMPLIFIED MID AND UPPER MID LATITUDE TROUGH MOVES TOWARD
THE EASTERN SEABOARD...AND PUSHES THE COLD FRONT SE TOWARD THE AREA
AS IT CROSSES THE MOUNTAIN CHAIN. STEADY HEIGHT FALLS WILL BE IN
SYNC WITH LOW LEVEL WARM ADVECTION TO GENERATE FAIRLY STEEP LAPSE
RATES FOR MID OCTOBER. THAT ALONG WITH UPPER DIFLUENCE AS A RESULT
OF THE RIGHT ENTRANCE REGION OF THE UPPER JET NEARBY AND MOISTURE
INCREASING AHEAD OF THE FRONT POINTS TOWARD OUR BEST RAIN CHANCES OF
THE SHORT TERM PERIOD. SINCE LOW LEVEL CONVERGENCE IS LIMITED WITH A
DEEP WEST TO SW FLOW...POPS WILL RISE ONLY INTO THE 30-40 PERCENT
RANGE FOR ALL BUT THE SE CORNER OF THE CWFA...WHERE 20 POPS WILL
SUFFICE. DUE TO THE PROGRESSIVE NATURE OF THIS NEXT FRONTAL SYSTEM
AND THE SHORT DURATION OF MOISTURE FLUX...QPF VALUES WILL BE LOW.
THERE IS CERTAINLY THE RISK...ALBEIT SMALL...FOR ISOLATED STRONG OR
SEVERE T-STORMS IN THE AFTERNOON. ALONG WITH THE FAVORABLE LAPSE
RATES THERE IS ALSO 25-30 KT OF 0-6 KM BULK SHEAR...AND SBCAPES WILL
BE AS HIGH AS 1000-1500 J/KG. THE STRONGER UPDRAFTS MIGHT THEN BE
ABLE TO PRODUCE STRONG AND GUSTY WINDS AS THEY COLLAPSE. ALTHOUGH OUR
INSOLATION WILL BE REDUCED BY AN INCREASE IN CLOUD COVER...THIS IS
NEGATED AT LEAST SOMEWHAT BY GOOD WARM ADVECTION AND COMPRESSIONAL
HEATING OUT AHEAD OF THE COLD FRONT. BEFORE ANY RAINS MOVE IN WE
LOOK FOR MAX READINGS IN THE LOWER AND MIDDLE 80S...FAR ABOVE NORMAL
FOR THIS TIME OF YEAR.
MONDAY NIGHT...THE FRONT WILL QUICKLY PUSH THROUGH THE AREA BY
06Z...AND RAPID DRYING AND COLD ADVECTION WILL ENSUE. WE/LL SEE
TEMPS DROP QUICK AND STEADILY IN WAKE OF THE FRONT...FALLING TO THE
LOWER AND MIDDLE 50S WEST...AND UPPER 50S AND LOWER 60S EAST BY
MORNING.
TUESDAY...A WESTERLY FLOW WILL SET IN ALOFT BEHIND THE DEPARTING
SHORT WAVE TROUGH THAT MOVES INTO THE ATLANTIC...AND IS RESPONSIBLE
FOR CAPTURING TC RAFAEL AND LIFTING IT OFF TO THE NE AND EAST WELL
OUT IN THE ATLANTIC. WEAK CONTINENTAL HIGH PRESSURE IN THE OH/TN
VALLEYS WILL MOVE IN...GENERATING A COOLER AIR MASS ON A NORTHERLY
FLOW WITH TEMPS AT 850 MB ARE DOWN NEAR 8-10C. EVEN WITH FULL
SUNSHINE WE/LL BE LIMITED TO MAYBE THE MID AND UPPER 70S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE CENTER OF WEAK HIGH PRESSURE WILL STEADILY SHIFT EASTWARD
THROUGH MID WEEK...BEFORE ANOTHER ROUND OF SHORTWAVE ENERGY SLIPS
FROM CENTRAL CANADA AND SPAWNS A ROBUST LOW SYSTEM OVER THE GREAT
LAKE REGION BY THURSDAY. THE TRAILING COLD FRONT WILL MOVE TOWARD
THE EAST COAST BY EARLY FRIDAY. HOWEVER...MOST DEEP MOISTURE AND
UPPER LEVEL ENERGY IS EXPECTED TO REMAIN DETACHED TO THE NORTH
WITH THE MAIN SYSTEM...SUGGESTING THAT THE FRONT COULD RUN OUT OF
STEAM UPON APPROACH TO THE FORECAST AREA. PREFER TO THUS MAINTAIN
A RATHER CONSERVATIVE POP SCHEME FOR THE EXTENDED PERIOD AND CAP
RAIN CHANCES BELOW 15 PERCENT WEDNESDAY THROUGH SATURDAY. HIGH
TEMPERATURES WILL RANGE FROM THE UPPER 70S NORTH TO AROUND 80
DEGREES NEAR THE ALTAMAHA RIVER IN SOUTHEAST GEORGIA. LOW
TEMPERATURES WILL GENERALLY FALL INTO THE 50S INLAND EACH
NIGHT...WITH SOME MID AND UPPER 40S LIKELY TUESDAY NIGHT UNDER IDEAL
RADIATIONAL COOLING CONDITIONS.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
VFR. LOW CHANCE FOR HIGH-END MVFR CIGS AT KSAV THROUGH
SUNRISE...BUT CIGS ARE EXPECTED TO REMAIN VFR. COULD ALSO SEE SOME
PATCHY GROUND FOG AT KCHS...BUT DO NOT ANTICIPATE ANY SIGNIFICANT
REDUCTIONS IN VISIBILITIES.
EXTENDED AVIATION OUTLOOK...MVFR OR LOWER CONDITIONS POSSIBLE IN
FOG SUNDAY NIGHT/MORNING MORNING. PERIODIC MVFR CONDITIONS POSSIBLE
IN SCATTERED SHRA/ISOLATED TSRA LATE MONDAY IN ASSOCIATION WITH A
COLD FRONT. VFR WEATHER WILL OTHERWISE PREVAIL.
&&
.MARINE...
OVERNIGHT...REPORTS FROM THE CHARLESTON HARBOR PILOT BOAT INDICATE
WINDS AND SEAS HAVE DIMINISHED BELOW SMALL CRAFT ADVISORY
THRESHOLDS ACROSS THE CHARLESTON COUNTY COASTAL WATERS. HAVE
CANCELLED THE ADVISORY FOR THESE WATERS. HOWEVER...IT REMAINS IN
FORCE ELSEWHERE.
SUNDAY AND SUNDAY NIGHT...HIGH PRESSURE FROM THE ATLANTIC AND
EXTENDING ACROSS THE LOCAL WATERS WILL STEADILY WEAKEN AS THE CORE
OF THE HIGH PULLS OUT TO THE EAST IN ADVANCE OF LOW PRESSURE MOVING
INTO THE GREAT LAKES STATES AND FAR SOUTHERN CANADA. WINDS WILL
STEADILY DIMINISH AS A RESULT...BUT SEAS WILL TAKE LONGER IN COMING
DOWN WITH LINGERING SWELL ENERGY. AS A RESULT WE STILL LOOK FOR 6
FOOTERS TO REMAIN ACROSS THE OUTER GA WATERS INTO THE FIRST PART OF
SUNDAY NIGHT...THUS A CONTINUATION OF THE SCA ACROSS AMZ374. THE
REST OF THE COASTAL WATERS WILL EXPERIENCE COMBINED SEAS AT 5 FEET
OR LESS.
MONDAY AND MONDAY NIGHT...WE/LL START THE PERIOD WITH EITHER A WEAK
PRESSURE PATTERN OR A WEAK COASTAL TROUGH...BEFORE THE SYNOPTIC
PATTERN CHANGES TO THE APPROACH AND EVENTUAL PASSAGE OF A COLD
FRONT. A LIGHT WIND REGIME IN ADVANCE OF THE FRONT WILL BE FOLLOWED
BY STRENGTHENING COLD ADVECTION THE SECOND PART OF MONDAY
NIGHT...CAUSING WINDS TO VEER FROM WEST AND SW AROUND TO THE NW AND
NORTH. SPEEDS WILL TAKE A SHARP TURN UPWARDS...REACHING 15 OR EVEN
20 KT LATE. WILL WILL GENERALLY BE AROUND 5 FT...A MIX OF BOTH
SWELLS AND WIND DRIVEN WAVES...BUT WE/LL NEED TO KEEP WATCH FOR
POSSIBLE 6 FOOTERS AGAIN ACROSS AMZ374.
TUESDAY...COLD ADVECTION IN THE MORNING WILL DROP OFF FOR THE
AFTERNOON...AND THAT ALONG WITH A MUCH MORE RELAXED PRESSURE
GRADIENT TO DEVELOP AS THE PRESSURE DIFFERENCE BETWEEN TC RAFAEL AND
WEAK HIGH PRESSURE TO THE WEST DIMINISHES. WE/LL BE CLOSE TO SCA
CONDITIONS...ESPECIALLY ACROSS AMZ374...ESPECIALLY IF ANY SWELLS
FROM RAFAEL ARE ABLE TO ARRIVE BEFORE THAT SYSTEM TURNS OFF TO THE
NE AND EAST.
WEDNESDAY...WEAK HIGH PRESSURE SETTLES ACROSS THE MARINE AREA.
ALTHOUGH WINDS WON/T BE A CONCERN...SEAS WILL REMAIN ELEVATED WITH
SWELL ENERGY STILL PERSISTING.
RIP CURRENTS...WITH STRONGER THAN EXPECTED WINDS ALONG THE
CHARLESTON COUNTY COAST HAVE RAISED THEIR RISK TO HIGH FOR THE
REST OF THE DAY. ELSEWHERE A HIGH RISK REMAINS IN EFFECT.
ALTHOUGH THERE IS A MUCH LIGHTER ONSHORE FLOW FOR SUNDAY...GIVEN
THAT SMALL SWELLS WILL PERSIST AND WE HAVE SOME ENHANCEMENT FROM
THE UPCOMING NEW MOON AND PERIGEE...THE RISK FOR RIP CURRENTS IS
STILL ELEVATED AND IN THE MODERATE RANGE.
&&
.TIDES/COASTAL FLOODING...
TIDE LEVELS WILL REMAIN ELEVATED INTO THE MIDDLE OF NEXT WEEK
MAINLY DUE TO THE PERIGEAN SPRING TIDE. THERE IS A GOOD CHANCE
THAT TIDES WILL BE HIGH ENOUGH TO PRODUCE SOME INUNDATION OF
SALTWATER IN NORMALLY PRONE AREAS EITHER SUNDAY OR MONDAY
MORNING...AND CONTINUING THROUGH AT LEAST WEDNESDAY. AS A
RESULT...COASTAL FLOOD ADVISORIES WILL LIKELY BE NEEDED FOR AT
LEAST THE TIMES AROUND THE MORNING HIGH TIDE EACH DAY DURING THIS
TIME.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EDT EARLY THIS MORNING FOR
AMZ352-354.
SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR AMZ374.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...
MARINE...
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1018 AM EDT SUN OCT 14 2012
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 325 AM EDT SUN OCT 14 2012
LOW PRESSURE CENTERED OUT IN THE PLAINS WILL CONTINUE TO MOVE
TOWARDS THE GREAT LAKES REGION FOR THE END OF THE WEEKEND. A STRONG
COLD FRONT ASSOCIATED WITH THIS SYSTEM WILL CROSS CENTRAL INDIANA
TODAY BRINGING THE CHANCE FOR SHOWERS AND THUNDERSTORMS TO THE
AREA...WITH THE POSSIBILITY OF STRONG TO SEVERE STORMS.
ADDITIONALLY...STRONG SOUTHERLY WINDS WITH GUSTS OVER 40 MPH ARE
POSSIBLE THIS AFTERNOON AS THE LOW CONTINUES TO STRENGTHEN.
HIGH PRESSURE WILL RETURN TO THE AREA ON MONDAY WITH DRY CONDITIONS
EXPECTED TO CONTINUE FOR ROUGHLY THE FIRST HALF OF THE WORK WEEK.
ANOTHER SYSTEM IS EXPECTED TO IMPACT THE REGION MIDWEEK BRINGING
ADDITIONAL CHANCES FOR PRECIPITATION HEADING INTO NEXT WEEKEND.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 945 AM EDT SUN OCT 14 2012
UPDATED FORECAST BASED ON LATEST RADAR TRENDS. DOWNPLAYED CHANCES
FOR THUNDER UNTIL THIS AFTERNOON AND LOWERED POPS THIS MORNING
ACROSS THE NORTHWEST. ALSO UPDATED PRODUCTS TO REFLECT EXPANSION OF
SLIGHT RISK TO THE ENTIRE FORECAST AREA BY SPC. WILL HAVE TO WATCH
CLEAR SLOT DEVELOPING ACROSS MISSOURI FOR IMPACTS ON CONVECTIVE
DEVELOPMENT AND ON SKY/TEMPERATURES.
PREVIOUS DISCUSSION FOLLOWS...
FORECAST CONCERNS FOR THE NEAR TERM CONTINUE TO BE THE STRONG WINDS
EXPECTED THIS AFTERNOON AS WELL AS THE POTENTIAL FOR SEVERE STORMS
AS A COLD FRONT PASSES THROUGH THE AREA.
WINDS ARE NOT AS STRONG THIS MORNING AS PREVIOUSLY FORECAST WITH THE
PRESSURE GRADIENT TAKING A BIT LONGER TO TIGHTEN UP AS THE LOW IS
SLOWER TO DEEPEN THAN EXPECTED. CURRENT THINKING IS THAT THE HIGHEST
SUSTAINED SPEEDS (20-25 MPH) AND ASSOCIATED GUSTS (40-45 MPH) WILL
NOT MIX DOWN UNTIL CLOSER TO 15Z...RATHER THAN AS EARLY AS 12Z.
THEREFORE...WILL DELAY THE START OF THE WIND ADVISORY TO 15Z. EVEN
WITH THE GRADIENT STAYING FAIRLY STRONG SUNDAY EVENING...WINDS
SHOULD BE ABLE TO SUBSIDE ENOUGH AFTER SUNSET SO AN END TIME OF
00Z MONDAY STILL SEEMS REASONABLE.
LATEST RADAR MOSAIC DISPLAYS A FAIRLY LARGE AREA OF PREFRONTAL
PRECIPITATION ACROSS NORTHERN AND WESTERN ILLINOIS SLIDING INTO
NORTHWEST INDIANA. THE HRRR SUGGESTS THIS SHOULD HOLD TOGETHER BUT
STAY JUST NORTH AND WEST OF THE FORECAST AREA. THIS MAKES SENSE DUE
TO THE LOCATION OF THE LEFT EXIT REGION OF THE 50-60 KT 850 MB JET.
THEREFORE...HAVE TRIMMED BACK POPS FOR THE MORNING HOURS..ESPECIALLY
ACROSS THE EASTERN ZONES.
MODELS DISPLAY SOME VARIABILITY IN TIMING THE ARRIVAL OF THE COLD
FRONT AND ITS ASSOCIATED PRECIPITATION. THE NAM AND ECMWF APPEAR TO
BE THE FASTEST WITH QPF ENCOMPASSING A MAJORITY OF THE FORECAST AREA
BY 12Z WHILE THE GFS APPEARS TO BE MORE IN LINE WITH THE HRRR.
REGARDLESS...ALL MODELS DEPICT THE BULK OF THE PRECIPITATION
IMPACTING THE AREA IN THE 18-00Z TIME FRAME SO HAVE HIT POPS THE
HARDEST DURING THE LATE AFTERNOON AND EARLY EVENING HOURS.
IN REGARDS TO SEVERE POTENTIAL...INSTABILITY LOOKS TO BE RESPECTABLE
WITH AROUND 500-750 J/KG TO WORK WITH BY MID TO LATE AFTERNOON.
HOWEVER...THE DYNAMICS APPEAR TO PROVIDE QUITE A BIT MORE SUPPORT
WITH THE FORCING FROM THE COLD FRONT BEING SUPPORTED BY THE UPPER
WAVE. WITH THE GFS DEPICTING 925 MB WINDS APPROACHING 60 KTS...ANY
DECENT STORMS THAT GET GOING SHOULD NOT HAVE TOO HARD OF A TIME
BRINGING SOME OF THAT DOWN TO THE SURFACE. THEREFORE...CONTINUE TO
EXPECT DAMAGING WINDS TO BE THE MAIN THREAT BUT THE POSSIBILITY FOR
SOME LARGE HAIL AND AN ISOLATED TORNADO OR TWO ARE NOT OUT OF THE
QUESTION.
WITH THE INFLUX OF WARM AND MOIST AIR CONTINUING AS SOUTHERLY WINDS
INCREASE...HIGH TEMPERATURES LOOK TO BE SIMILAR TO SATURDAY...IF NOT
A DEGREE OR TWO HIGHER...RANGING FROM THE LOW 70S ACROSS THE NORTH
TO THE MID 70S IN THE SOUTH.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 325 AM EDT SUN OCT 14 2012
WITH THE UPPER WAVE SLOW TO MOVE OUT OF THE REGION...HAVE HUNG ON TO
SMALL POPS FOR SUNDAY EVENING TO ACCOUNT FOR ANY LINGERING SHOWERS
OR THUNDERSTORMS. HIGH PRESSURE WILL THEN BUILD INTO THE REGION FOR
THE BEGINNING OF THE WORK WEEK ALLOWING DRY CONDITIONS TO RETURN FOR
THE REMAINDER OF THE PERIOD.
NORTHWEST WINDS FOLLOWING FRONTAL PASSAGE WILL ALLOW TEMPERATURES TO
DROP A BIT BUT HIGHS SHOULD BE NEAR NORMAL VALUES (MID 60S) WITH A
FAIR AMOUNT OF SUNSHINE ON BOTH MONDAY AND TUESDAY. LOW TEMPERATURES
LOOK TO REMAIN MILD (UPPER 40S TO LOW 50S) EXCEPT FOR MONDAY NIGHT
WITH THE CENTER OF THE HIGH RIGHT OVER THE AREA WHEN TEMPERATURES
COULD FALL TO AROUND 40 DEGREES.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 325 AM EDT SUN OCT 14 2012
UNSETTLED WEATHER WILL BE THE RULE...ESPECIALLY EARLY ON. A STRONG
UPPER LOW WILL MOVE INTO THE NORTHERN PLAINS WEDNESDAY AND THEN
TRACK INTO OUR REGION TOWARDS THE WEEKEND WITH SOME MODELS MOVING IT
ON TO THE EAST OVER THE WEEKEND. MODELS INDICATE A STRONG COLD
FRONT WILL MOVE ACROSS OUR REGION LATE WEDNESDAY NIGHT OR EARLY
THURSDAY. ON WEDNESDAY WE CAN EXPECT INCREASING CLOUDS WITH A CHANCE
OF PRECIP LATE ACROSS OUR NORTHWEST HALF. RAISED ALL BLEND
TEMPERATURES SLIGHTLY AS WARM ADVECTION WILL BE OCCURRING AHEAD OF
FRONT AND MEX NUMBERS WERE RUNNING ABOUT 5 DEGREES WARMER.
WILL CONTINUE LIKELY POPS MOST AREAS WEDNESDAY NIGHT AS FRONT MOVES
THROUGH AND THEN THERE IS SOME QUESTION ON THURSDAY AS A DRY SLOT
PUSHES INTO OUR WEST. FOR NOW WILL ACCEPT ALL BLEND POPS WHICH HAS
SLIGHT CHANCE POPS ACROSS OUR WEST AND CHANCE POPS FATHER EAST.
WILL CONTINUE LOW POPS MOST AREAS REST OF FORECAST AS UPPER LOW
ROTATES INTO OUR REGION. BY DAY 7 GFS HAS IT WELL TO OUR EAST WHILE
NEW EURO STILL HAS IT ACROSS OUR REGION. EXCEPT FOR RAISING MINS A
LITTLE THURSDAY NIGHT AND FRIDAY NIGHT WITH CLOUDS...DID NOT MAKE
ANY SIGNIFICANT CHANGE TO ALL BLEND TEMPERATURES FOR THE REST OF THE
EXTENDED.
&&
.AVIATION /DISCUSSION FOR THE 141200Z TAF ISSUANCE/...
ISSUED AT 1015 AM EDT SUN OCT 14 2012
1430Z UPDATE...ONLY ADJUSTMENT MADE TO TAFS FOR THE NEXT FEW HOURS
WAS TO REMOVE MENTION OF VCTS. OTHERWISE NO OTHER CHANGES WERE
MADE AT THIS TIME. PREVIOUS DISCUSSION FOLLOWS...
MAIN ISSUES WILL BE NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS
TODAY AND STRONG WINDS WITH GUSTS TO 35 KNOTS LATER TODAY AS
PRESSURE GRADIENT BECOMES A LITTLE TIGHTER. A STRONG LOW PRESSURE
SYSTEM WILL TRACK TO NORTHERN LOWER MICHIGAN AND A COLD FRONT WILL
MOVE QUICKLY ACROSS OUR REGION BY LATE AFTERNOON. THE LOW PRESSURE
SYSTEM WILL MOVE TO EASTERN LAKE HURON BY LATE TONIGHT AND THE
PRESSURE GRADIENT AND WINDS WILL MODERATE SOME OVERNIGHT.
RADAR SHOWS NUMEROUS SHOWERS AND A FEW THUNDERSTORMS FROM THE
INDIANA ILLINOIS BORDER ON WEST AND THESE WILL SPREAD RAPIDLY EAST
ACROSS TAF SITES NEXT FEW HOURS. SINCE NOT MUCH LIGHTNING PRESENTLY
OCCURRING WILL START TAFS OUT WITH SHOWERS AND MENTION VCTS. RAPID
REFRESH INDICATES A BETTER CHANCE OF THUNDERSTORMS OCCURRING BY
MIDDAY WITH SOME DAYTIME HEATING AND BETTER MIXING WILL CAUSE WIND
GUSTS TO INCREASE TO 35 TO 40 KNOTS. WILL PLAY UP THUNDERSTORMS A
LITTLE MORE THIS PERIOD.
AFTER COLD FRONT MOVES THROUGH SHOWERS AND THUNDERSTORMS WILL
DIMINISH BY LATE AFTERNOON...BUT A FEW SHOWERS WILL LINGER INTO THE
EVENING HOURS. WINDS WILL GRADUALLY DIMINISH THIS EVENING DROPPING
TO 10 TO 15 KNOTS MOST AREAS BY MIDNIGHT.
EXPECT CEILINGS TO AVERAGE AROUND 3 THOUSAND MUCH OF THE
PERIOD...BUT COULD AT TIMES DROP TO LESS THAN 2 THOUSAND FEET IN
SHOWERS AND THUNDERSTORMS LATER TODAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 8 PM EDT THIS EVENING FOR INZ021-028>031-
035>049-051>057-060>065-067>072.
&&
$$
SYNOPSIS...HOMANN
NEAR TERM...HOMANN/50
SHORT TERM...HOMANN
LONG TERM....JEH
AVIATION...SMF
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
945 AM EDT SUN OCT 14 2012
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 325 AM EDT SUN OCT 14 2012
LOW PRESSURE CENTERED OUT IN THE PLAINS WILL CONTINUE TO MOVE
TOWARDS THE GREAT LAKES REGION FOR THE END OF THE WEEKEND. A STRONG
COLD FRONT ASSOCIATED WITH THIS SYSTEM WILL CROSS CENTRAL INDIANA
TODAY BRINGING THE CHANCE FOR SHOWERS AND THUNDERSTORMS TO THE
AREA...WITH THE POSSIBILITY OF STRONG TO SEVERE STORMS.
ADDITIONALLY...STRONG SOUTHERLY WINDS WITH GUSTS OVER 40 MPH ARE
POSSIBLE THIS AFTERNOON AS THE LOW CONTINUES TO STRENGTHEN.
HIGH PRESSURE WILL RETURN TO THE AREA ON MONDAY WITH DRY CONDITIONS
EXPECTED TO CONTINUE FOR ROUGHLY THE FIRST HALF OF THE WORK WEEK.
ANOTHER SYSTEM IS EXPECTED TO IMPACT THE REGION MIDWEEK BRINGING
ADDITIONAL CHANCES FOR PRECIPITATION HEADING INTO NEXT WEEKEND.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 945 AM EDT SUN OCT 14 2012
UPDATED FORECAST BASED ON LATEST RADAR TRENDS. DOWNPLAYED CHANCES
FOR THUNDER UNTIL THIS AFTERNOON AND LOWERED POPS THIS MORNING
ACROSS THE NORTHWEST. ALSO UPDATED PRODUCTS TO REFLECT EXPANSION OF
SLIGHT RISK TO THE ENTIRE FORECAST AREA BY SPC. WILL HAVE TO WATCH
CLEAR SLOT DEVELOPING ACROSS MISSOURI FOR IMPACTS ON CONVECTIVE
DEVELOPMENT AND ON SKY/TEMPERATURES.
PREVIOUS DISCUSSION FOLLOWS...
FORECAST CONCERNS FOR THE NEAR TERM CONTINUE TO BE THE STRONG WINDS
EXPECTED THIS AFTERNOON AS WELL AS THE POTENTIAL FOR SEVERE STORMS
AS A COLD FRONT PASSES THROUGH THE AREA.
WINDS ARE NOT AS STRONG THIS MORNING AS PREVIOUSLY FORECAST WITH THE
PRESSURE GRADIENT TAKING A BIT LONGER TO TIGHTEN UP AS THE LOW IS
SLOWER TO DEEPEN THAN EXPECTED. CURRENT THINKING IS THAT THE HIGHEST
SUSTAINED SPEEDS (20-25 MPH) AND ASSOCIATED GUSTS (40-45 MPH) WILL
NOT MIX DOWN UNTIL CLOSER TO 15Z...RATHER THAN AS EARLY AS 12Z.
THEREFORE...WILL DELAY THE START OF THE WIND ADVISORY TO 15Z. EVEN
WITH THE GRADIENT STAYING FAIRLY STRONG SUNDAY EVENING...WINDS
SHOULD BE ABLE TO SUBSIDE ENOUGH AFTER SUNSET SO AN END TIME OF
00Z MONDAY STILL SEEMS REASONABLE.
LATEST RADAR MOSAIC DISPLAYS A FAIRLY LARGE AREA OF PREFRONTAL
PRECIPITATION ACROSS NORTHERN AND WESTERN ILLINOIS SLIDING INTO
NORTHWEST INDIANA. THE HRRR SUGGESTS THIS SHOULD HOLD TOGETHER BUT
STAY JUST NORTH AND WEST OF THE FORECAST AREA. THIS MAKES SENSE DUE
TO THE LOCATION OF THE LEFT EXIT REGION OF THE 50-60 KT 850 MB JET.
THEREFORE...HAVE TRIMMED BACK POPS FOR THE MORNING HOURS..ESPECIALLY
ACROSS THE EASTERN ZONES.
MODELS DISPLAY SOME VARIABILITY IN TIMING THE ARRIVAL OF THE COLD
FRONT AND ITS ASSOCIATED PRECIPITATION. THE NAM AND ECMWF APPEAR TO
BE THE FASTEST WITH QPF ENCOMPASSING A MAJORITY OF THE FORECAST AREA
BY 12Z WHILE THE GFS APPEARS TO BE MORE IN LINE WITH THE HRRR.
REGARDLESS...ALL MODELS DEPICT THE BULK OF THE PRECIPITATION
IMPACTING THE AREA IN THE 18-00Z TIME FRAME SO HAVE HIT POPS THE
HARDEST DURING THE LATE AFTERNOON AND EARLY EVENING HOURS.
IN REGARDS TO SEVERE POTENTIAL...INSTABILITY LOOKS TO BE RESPECTABLE
WITH AROUND 500-750 J/KG TO WORK WITH BY MID TO LATE AFTERNOON.
HOWEVER...THE DYNAMICS APPEAR TO PROVIDE QUITE A BIT MORE SUPPORT
WITH THE FORCING FROM THE COLD FRONT BEING SUPPORTED BY THE UPPER
WAVE. WITH THE GFS DEPICTING 925 MB WINDS APPROACHING 60 KTS...ANY
DECENT STORMS THAT GET GOING SHOULD NOT HAVE TOO HARD OF A TIME
BRINGING SOME OF THAT DOWN TO THE SURFACE. THEREFORE...CONTINUE TO
EXPECT DAMAGING WINDS TO BE THE MAIN THREAT BUT THE POSSIBILITY FOR
SOME LARGE HAIL AND AN ISOLATED TORNADO OR TWO ARE NOT OUT OF THE
QUESTION.
WITH THE INFLUX OF WARM AND MOIST AIR CONTINUING AS SOUTHERLY WINDS
INCREASE...HIGH TEMPERATURES LOOK TO BE SIMILAR TO SATURDAY...IF NOT
A DEGREE OR TWO HIGHER...RANGING FROM THE LOW 70S ACROSS THE NORTH
TO THE MID 70S IN THE SOUTH.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 325 AM EDT SUN OCT 14 2012
WITH THE UPPER WAVE SLOW TO MOVE OUT OF THE REGION...HAVE HUNG ON TO
SMALL POPS FOR SUNDAY EVENING TO ACCOUNT FOR ANY LINGERING SHOWERS
OR THUNDERSTORMS. HIGH PRESSURE WILL THEN BUILD INTO THE REGION FOR
THE BEGINNING OF THE WORK WEEK ALLOWING DRY CONDITIONS TO RETURN FOR
THE REMAINDER OF THE PERIOD.
NORTHWEST WINDS FOLLOWING FRONTAL PASSAGE WILL ALLOW TEMPERATURES TO
DROP A BIT BUT HIGHS SHOULD BE NEAR NORMAL VALUES (MID 60S) WITH A
FAIR AMOUNT OF SUNSHINE ON BOTH MONDAY AND TUESDAY. LOW TEMPERATURES
LOOK TO REMAIN MILD (UPPER 40S TO LOW 50S) EXCEPT FOR MONDAY NIGHT
WITH THE CENTER OF THE HIGH RIGHT OVER THE AREA WHEN TEMPERATURES
COULD FALL TO AROUND 40 DEGREES.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 325 AM EDT SUN OCT 14 2012
UNSETTLED WEATHER WILL BE THE RULE...ESPECIALLY EARLY ON. A STRONG
UPPER LOW WILL MOVE INTO THE NORTHERN PLAINS WEDNESDAY AND THEN
TRACK INTO OUR REGION TOWARDS THE WEEKEND WITH SOME MODELS MOVING IT
ON TO THE EAST OVER THE WEEKEND. MODELS INDICATE A STRONG COLD
FRONT WILL MOVE ACROSS OUR REGION LATE WEDNESDAY NIGHT OR EARLY
THURSDAY. ON WEDNESDAY WE CAN EXPECT INCREASING CLOUDS WITH A CHANCE
OF PRECIP LATE ACROSS OUR NORTHWEST HALF. RAISED ALL BLEND
TEMPERATURES SLIGHTLY AS WARM ADVECTION WILL BE OCCURRING AHEAD OF
FRONT AND MEX NUMBERS WERE RUNNING ABOUT 5 DEGREES WARMER.
WILL CONTINUE LIKELY POPS MOST AREAS WEDNESDAY NIGHT AS FRONT MOVES
THROUGH AND THEN THERE IS SOME QUESTION ON THURSDAY AS A DRY SLOT
PUSHES INTO OUR WEST. FOR NOW WILL ACCEPT ALL BLEND POPS WHICH HAS
SLIGHT CHANCE POPS ACROSS OUR WEST AND CHANCE POPS FATHER EAST.
WILL CONTINUE LOW POPS MOST AREAS REST OF FORECAST AS UPPER LOW
ROTATES INTO OUR REGION. BY DAY 7 GFS HAS IT WELL TO OUR EAST WHILE
NEW EURO STILL HAS IT ACROSS OUR REGION. EXCEPT FOR RAISING MINS A
LITTLE THURSDAY NIGHT AND FRIDAY NIGHT WITH CLOUDS...DID NOT MAKE
ANY SIGNIFICANT CHANGE TO ALL BLEND TEMPERATURES FOR THE REST OF THE
EXTENDED.
&&
.AVIATION /DISCUSSION FOR THE 141200Z TAF ISSUANCE/...
ISSUED AT 650 AM EDT SUN OCT 14 2012
MAIN ISSUES WILL BE NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS
TODAY AND STRONG WINDS WITH GUSTS TO 35 KNOTS LATER TODAY AS
PRESSURE GRADIENT BECOMES A LITTLE TIGHTER. A STRONG LOW PRESSURE
SYSTEM WILL TRACK TO NORTHERN LOWER MICHIGAN AND A COLD FRONT WILL
MOVE QUICKLY ACROSS OUR REGION BY LATE AFTERNOON. THE LOW PRESSURE
SYSTEM WILL MOVE TO EASTERN LAKE HURON BY LATE TONIGHT AND THE
PRESSURE GRADIENT AND WINDS WILL MODERATE SOME OVERNIGHT.
RADAR SHOWS NUMEROUS SHOWERS AND A FEW THUNDERSTORMS FROM THE
INDIANA ILLINOIS BORDER ON WEST AND THESE WILL SPREAD RAPIDLY EAST
ACROSS TAF SITES NEXT FEW HOURS. SINCE NOT MUCH LIGHTNING PRESENTLY
OCCURRING WILL START TAFS OUT WITH SHOWERS AND MENTION VCTS. RAPID
REFRESH INDICATES A BETTER CHANCE OF THUNDERSTORMS OCCURRING BY
MIDDAY WITH SOME DAYTIME HEATING AND BETTER MIXING WILL CAUSE WIND
GUSTS TO INCREASE TO 35 TO 40 KNOTS. WILL PLAY UP THUNDERSTORMS A
LITTLE MORE THIS PERIOD.
AFTER COLD FRONT MOVES THROUGH SHOWERS AND THUNDERSTORMS WILL
DIMINISH BY LATE AFTERNOON...BUT A FEW SHOWERS WILL LINGER INTO THE
EVENING HOURS. WINDS WILL GRADUALLY DIMINISH THIS EVENING DROPPING
TO 10 TO 15 KNOTS MOST AREAS BY MIDNIGHT.
EXPECT CEILINGS TO AVERAGE AROUND 3 THOUSAND MUCH OF THE
PERIOD...BUT COULD AT TIMES DROP TO LESS THAN 2 THOUSAND FEET IN
SHOWERS AND THUNDERSTORMS LATER TODAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 11 AM THIS MORNING TO 8 PM EDT THIS EVENING FOR
INZ021-028>031-035>049-051>057-060>065-067>072.
&&
$$
SYNOPSIS...HOMANN
NEAR TERM...HOMANN/50
SHORT TERM...HOMANN
LONG TERM....JEH
AVIATION...JEH
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
650 AM EDT SUN OCT 14 2012
.UPDATE...
AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 325 AM EDT SUN OCT 14 2012
LOW PRESSURE CENTERED OUT IN THE PLAINS WILL CONTINUE TO MOVE
TOWARDS THE GREAT LAKES REGION FOR THE END OF THE WEEKEND. A STRONG
COLD FRONT ASSOCIATED WITH THIS SYSTEM WILL CROSS CENTRAL INDIANA
TODAY BRINGING THE CHANCE FOR SHOWERS AND THUNDERSTORMS TO THE
AREA...WITH THE POSSIBILITY OF STRONG TO SEVERE STORMS.
ADDITIONALLY...STRONG SOUTHERLY WINDS WITH GUSTS OVER 40 MPH ARE
POSSIBLE THIS AFTERNOON AS THE LOW CONTINUES TO STRENGTHEN.
HIGH PRESSURE WILL RETURN TO THE AREA ON MONDAY WITH DRY CONDITIONS
EXPECTED TO CONTINUE FOR ROUGHLY THE FIRST HALF OF THE WORK WEEK.
ANOTHER SYSTEM IS EXPECTED TO IMPACT THE REGION MIDWEEK BRINGING
ADDITIONAL CHANCES FOR PRECIPITATION HEADING INTO NEXT WEEKEND.
&&
.NEAR TERM /TODAY/...
ISSUED AT 325 AM EDT SUN OCT 14 2012
FORECAST CONCERNS FOR THE NEAR TERM CONTINUE TO BE THE STRONG WINDS
EXPECTED THIS AFTERNOON AS WELL AS THE POTENTIAL FOR SEVERE STORMS
AS A COLD FRONT PASSES THROUGH THE AREA.
WINDS ARE NOT AS STRONG THIS MORNING AS PREVIOUSLY FORECAST WITH THE
PRESSURE GRADIENT TAKING A BIT LONGER TO TIGHTEN UP AS THE LOW IS
SLOWER TO DEEPEN THAN EXPECTED. CURRENT THINKING IS THAT THE HIGHEST
SUSTAINED SPEEDS (20-25 MPH) AND ASSOCIATED GUSTS (40-45 MPH) WILL
NOT MIX DOWN UNTIL CLOSER TO 15Z...RATHER THAN AS EARLY AS 12Z.
THEREFORE...WILL DELAY THE START OF THE WIND ADVISORY TO 15Z. EVEN
WITH THE GRADIENT STAYING FAIRLY STRONG SUNDAY EVENING...WINDS
SHOULD BE ABLE TO SUBSIDE ENOUGH AFTER SUNSET SO AN END TIME OF
00Z MONDAY STILL SEEMS REASONABLE.
LATEST RADAR MOSAIC DISPLAYS A FAIRLY LARGE AREA OF PREFRONTAL
PRECIPITATION ACROSS NORTHERN AND WESTERN ILLINOIS SLIDING INTO
NORTHWEST INDIANA. THE HRRR SUGGESTS THIS SHOULD HOLD TOGETHER BUT
STAY JUST NORTH AND WEST OF THE FORECAST AREA. THIS MAKES SENSE DUE
TO THE LOCATION OF THE LEFT EXIT REGION OF THE 50-60 KT 850 MB JET.
THEREFORE...HAVE TRIMMED BACK POPS FOR THE MORNING HOURS..ESPECIALLY
ACROSS THE EASTERN ZONES.
MODELS DISPLAY SOME VARIABILITY IN TIMING THE ARRIVAL OF THE COLD
FRONT AND ITS ASSOCIATED PRECIPITATION. THE NAM AND ECMWF APPEAR TO
BE THE FASTEST WITH QPF ENCOMPASSING A MAJORITY OF THE FORECAST AREA
BY 12Z WHILE THE GFS APPEARS TO BE MORE IN LINE WITH THE HRRR.
REGARDLESS...ALL MODELS DEPICT THE BULK OF THE PRECIPITATION
IMPACTING THE AREA IN THE 18-00Z TIME FRAME SO HAVE HIT POPS THE
HARDEST DURING THE LATE AFTERNOON AND EARLY EVENING HOURS.
IN REGARDS TO SEVERE POTENTIAL...INSTABILITY LOOKS TO BE RESPECTABLE
WITH AROUND 500-750 J/KG TO WORK WITH BY MID TO LATE AFTERNOON.
HOWEVER...THE DYNAMICS APPEAR TO PROVIDE QUITE A BIT MORE SUPPORT
WITH THE FORCING FROM THE COLD FRONT BEING SUPPORTED BY THE UPPER
WAVE. WITH THE GFS DEPICTING 925 MB WINDS APPROACHING 60 KTS...ANY
DECENT STORMS THAT GET GOING SHOULD NOT HAVE TOO HARD OF A TIME
BRINGING SOME OF THAT DOWN TO THE SURFACE. THEREFORE...CONTINUE TO
EXPECT DAMAGING WINDS TO BE THE MAIN THREAT BUT THE POSSIBILITY FOR
SOME LARGE HAIL AND AN ISOLATED TORNADO OR TWO ARE NOT OUT OF THE
QUESTION.
WITH THE INFLUX OF WARM AND MOIST AIR CONTINUING AS SOUTHERLY WINDS
INCREASE...HIGH TEMPERATURES LOOK TO BE SIMILAR TO SATURDAY...IF NOT
A DEGREE OR TWO HIGHER...RANGING FROM THE LOW 70S ACROSS THE NORTH
TO THE MID 70S IN THE SOUTH.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 325 AM EDT SUN OCT 14 2012
WITH THE UPPER WAVE SLOW TO MOVE OUT OF THE REGION...HAVE HUNG ON TO
SMALL POPS FOR SUNDAY EVENING TO ACCOUNT FOR ANY LINGERING SHOWERS
OR THUNDERSTORMS. HIGH PRESSURE WILL THEN BUILD INTO THE REGION FOR
THE BEGINNING OF THE WORK WEEK ALLOWING DRY CONDITIONS TO RETURN FOR
THE REMAINDER OF THE PERIOD.
NORTHWEST WINDS FOLLOWING FRONTAL PASSAGE WILL ALLOW TEMPERATURES TO
DROP A BIT BUT HIGHS SHOULD BE NEAR NORMAL VALUES (MID 60S) WITH A
FAIR AMOUNT OF SUNSHINE ON BOTH MONDAY AND TUESDAY. LOW TEMPERATURES
LOOK TO REMAIN MILD (UPPER 40S TO LOW 50S) EXCEPT FOR MONDAY NIGHT
WITH THE CENTER OF THE HIGH RIGHT OVER THE AREA WHEN TEMPERATURES
COULD FALL TO AROUND 40 DEGREES.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 325 AM EDT SUN OCT 14 2012
UNSETTLED WEATHER WILL BE THE RULE...ESPECIALLY EARLY ON. A STRONG
UPPER LOW WILL MOVE INTO THE NORTHERN PLAINS WEDNESDAY AND THEN
TRACK INTO OUR REGION TOWARDS THE WEEKEND WITH SOME MODELS MOVING IT
ON TO THE EAST OVER THE WEEKEND. MODELS INDICATE A STRONG COLD
FRONT WILL MOVE ACROSS OUR REGION LATE WEDNESDAY NIGHT OR EARLY
THURSDAY. ON WEDNESDAY WE CAN EXPECT INCREASING CLOUDS WITH A CHANCE
OF PRECIP LATE ACROSS OUR NORTHWEST HALF. RAISED ALL BLEND
TEMPERATURES SLIGHTLY AS WARM ADVECTION WILL BE OCCURRING AHEAD OF
FRONT AND MEX NUMBERS WERE RUNNING ABOUT 5 DEGREES WARMER.
WILL CONTINUE LIKELY POPS MOST AREAS WEDNESDAY NIGHT AS FRONT MOVES
THROUGH AND THEN THERE IS SOME QUESTION ON THURSDAY AS A DRY SLOT
PUSHES INTO OUR WEST. FOR NOW WILL ACCEPT ALL BLEND POPS WHICH HAS
SLIGHT CHANCE POPS ACROSS OUR WEST AND CHANCE POPS FATHER EAST.
WILL CONTINUE LOW POPS MOST AREAS REST OF FORECAST AS UPPER LOW
ROTATES INTO OUR REGION. BY DAY 7 GFS HAS IT WELL TO OUR EAST WHILE
NEW EURO STILL HAS IT ACROSS OUR REGION. EXCEPT FOR RAISING MINS A
LITTLE THURSDAY NIGHT AND FRIDAY NIGHT WITH CLOUDS...DID NOT MAKE
ANY SIGNIFICANT CHANGE TO ALL BLEND TEMPERATURES FOR THE REST OF THE
EXTENDED.
&&
.AVIATION /DISCUSSION FOR THE 141200Z TAF ISSUANCE/...
ISSUED AT 650 AM EDT SUN OCT 14 2012
MAIN ISSUES WILL BE NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS
TODAY AND STRONG WINDS WITH GUSTS TO 35 KNOTS LATER TODAY AS
PRESSURE GRADIENT BECOMES A LITTLE TIGHTER. A STRONG LOW PRESSURE
SYSTEM WILL TRACK TO NORTHERN LOWER MICHIGAN AND A COLD FRONT WILL
MOVE QUICKLY ACROSS OUR REGION BY LATE AFTERNOON. THE LOW PRESSURE
SYSTEM WILL MOVE TO EASTERN LAKE HURON BY LATE TONIGHT AND THE
PRESSURE GRADIENT AND WINDS WILL MODERATE SOME OVERNIGHT.
RADAR SHOWS NUMEROUS SHOWERS AND A FEW THUNDERSTORMS FROM THE
INDIANA ILLINOIS BORDER ON WEST AND THESE WILL SPREAD RAPIDLY EAST
ACROSS TAF SITES NEXT FEW HOURS. SINCE NOT MUCH LIGHTNING PRESENTLY
OCCURRING WILL START TAFS OUT WITH SHOWERS AND MENTION VCTS. RAPID
REFRESH INDICATES A BETTER CHANCE OF THUNDERSTORMS OCCURRING BY
MIDDAY WITH SOME DAYTIME HEATING AND BETTER MIXING WILL CAUSE WIND
GUSTS TO INCREASE TO 35 TO 40 KNOTS. WILL PLAY UP THUNDERSTORMS A
LITTLE MORE THIS PERIOD.
AFTER COLD FRONT MOVES THROUGH SHOWERS AND THUNDERSTORMS WILL
DIMINISH BY LATE AFTERNOON...BUT A FEW SHOWERS WILL LINGER INTO THE
EVENING HOURS. WINDS WILL GRADUALLY DIMINISH THIS EVENING DROPPING
TO 10 TO 15 KNOTS MOST AREAS BY MIDNIGHT.
EXPECT CEILINGS TO AVERAGE AROUND 3 THOUSAND MUCH OF THE
PERIOD...BUT COULD AT TIMES DROP TO LESS THAN 2 THOUSAND FEET IN
SHOWERS AND THUNDERSTORMS LATER TODAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 11 AM THIS MORNING TO 8 PM EDT THIS EVENING FOR
INZ021-028>031-035>049-051>057-060>065-067>072.
&&
$$
SYNOPSIS...HOMANN
NEAR TERM...HOMANN
SHORT TERM...HOMANN
LONG TERM....JEH
AVIATION...JEH
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
430 AM EDT SUN OCT 14 2012
.UPDATE...
THE SYNOPSIS...NEAR TERM...SHORT TERM AND LONG TERM SECTIONS HAVE
BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 325 AM EDT SUN OCT 14 2012
LOW PRESSURE CENTERED OUT IN THE PLAINS WILL CONTINUE TO MOVE
TOWARDS THE GREAT LAKES REGION FOR THE END OF THE WEEKEND. A STRONG
COLD FRONT ASSOCIATED WITH THIS SYSTEM WILL CROSS CENTRAL INDIANA
TODAY BRINGING THE CHANCE FOR SHOWERS AND THUNDERSTORMS TO THE
AREA...WITH THE POSSIBILITY OF STRONG TO SEVERE STORMS.
ADDITIONALLY...STRONG SOUTHERLY WINDS WITH GUSTS OVER 40 MPH ARE
POSSIBLE THIS AFTERNOON AS THE LOW CONTINUES TO STRENGTHEN.
HIGH PRESSURE WILL RETURN TO THE AREA ON MONDAY WITH DRY CONDITIONS
EXPECTED TO CONTINUE FOR ROUGHLY THE FIRST HALF OF THE WORK WEEK.
ANOTHER SYSTEM IS EXPECTED TO IMPACT THE REGION MIDWEEK BRINGING
ADDITIONAL CHANCES FOR PRECIPITATION HEADING INTO NEXT WEEKEND.
&&
.NEAR TERM /TODAY/...
ISSUED AT 325 AM EDT SUN OCT 14 2012
FORECAST CONCERNS FOR THE NEAR TERM CONTINUE TO BE THE STRONG WINDS
EXPECTED THIS AFTERNOON AS WELL AS THE POTENTIAL FOR SEVERE STORMS
AS A COLD FRONT PASSES THROUGH THE AREA.
WINDS ARE NOT AS STRONG THIS MORNING AS PREVIOUSLY FORECAST WITH THE
PRESSURE GRADIENT TAKING A BIT LONGER TO TIGHTEN UP AS THE LOW IS
SLOWER TO DEEPEN THAN EXPECTED. CURRENT THINKING IS THAT THE HIGHEST
SUSTAINED SPEEDS (20-25 MPH) AND ASSOCIATED GUSTS (40-45 MPH) WILL
NOT MIX DOWN UNTIL CLOSER TO 15Z...RATHER THAN AS EARLY AS 12Z.
THEREFORE...WILL DELAY THE START OF THE WIND ADVISORY TO 15Z. EVEN
WITH THE GRADIENT STAYING FAIRLY STRONG SUNDAY EVENING...WINDS
SHOULD BE ABLE TO SUBSIDE ENOUGH AFTER SUNSET SO AN END TIME OF
00Z MONDAY STILL SEEMS REASONABLE.
LATEST RADAR MOSAIC DISPLAYS A FAIRLY LARGE AREA OF PREFRONTAL
PRECIPITATION ACROSS NORTHERN AND WESTERN ILLINOIS SLIDING INTO
NORTHWEST INDIANA. THE HRRR SUGGESTS THIS SHOULD HOLD TOGETHER BUT
STAY JUST NORTH AND WEST OF THE FORECAST AREA. THIS MAKES SENSE DUE
TO THE LOCATION OF THE LEFT EXIT REGION OF THE 50-60 KT 850 MB JET.
THEREFORE...HAVE TRIMMED BACK POPS FOR THE MORNING HOURS..ESPECIALLY
ACROSS THE EASTERN ZONES.
MODELS DISPLAY SOME VARIABILITY IN TIMING THE ARRIVAL OF THE COLD
FRONT AND ITS ASSOCIATED PRECIPITATION. THE NAM AND ECMWF APPEAR TO
BE THE FASTEST WITH QPF ENCOMPASSING A MAJORITY OF THE FORECAST AREA
BY 12Z WHILE THE GFS APPEARS TO BE MORE IN LINE WITH THE HRRR.
REGARDLESS...ALL MODELS DEPICT THE BULK OF THE PRECIPITATION
IMPACTING THE AREA IN THE 18-00Z TIME FRAME SO HAVE HIT POPS THE
HARDEST DURING THE LATE AFTERNOON AND EARLY EVENING HOURS.
IN REGARDS TO SEVERE POTENTIAL...INSTABILITY LOOKS TO BE RESPECTABLE
WITH AROUND 500-750 J/KG TO WORK WITH BY MID TO LATE AFTERNOON.
HOWEVER...THE DYNAMICS APPEAR TO PROVIDE QUITE A BIT MORE SUPPORT
WITH THE FORCING FROM THE COLD FRONT BEING SUPPORTED BY THE UPPER
WAVE. WITH THE GFS DEPICTING 925 MB WINDS APPROACHING 60 KTS...ANY
DECENT STORMS THAT GET GOING SHOULD NOT HAVE TOO HARD OF A TIME
BRINGING SOME OF THAT DOWN TO THE SURFACE. THEREFORE...CONTINUE TO
EXPECT DAMAGING WINDS TO BE THE MAIN THREAT BUT THE POSSIBILITY FOR
SOME LARGE HAIL AND AN ISOLATED TORNADO OR TWO ARE NOT OUT OF THE
QUESTION.
WITH THE INFLUX OF WARM AND MOIST AIR CONTINUING AS SOUTHERLY WINDS
INCREASE...HIGH TEMPERATURES LOOK TO BE SIMILAR TO SATURDAY...IF NOT
A DEGREE OR TWO HIGHER...RANGING FROM THE LOW 70S ACROSS THE NORTH
TO THE MID 70S IN THE SOUTH.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 325 AM EDT SUN OCT 14 2012
WITH THE UPPER WAVE SLOW TO MOVE OUT OF THE REGION...HAVE HUNG ON TO
SMALL POPS FOR SUNDAY EVENING TO ACCOUNT FOR ANY LINGERING SHOWERS
OR THUNDERSTORMS. HIGH PRESSURE WILL THEN BUILD INTO THE REGION FOR
THE BEGINNING OF THE WORK WEEK ALLOWING DRY CONDITIONS TO RETURN FOR
THE REMAINDER OF THE PERIOD.
NORTHWEST WINDS FOLLOWING FRONTAL PASSAGE WILL ALLOW TEMPERATURES TO
DROP A BIT BUT HIGHS SHOULD BE NEAR NORMAL VALUES (MID 60S) WITH A
FAIR AMOUNT OF SUNSHINE ON BOTH MONDAY AND TUESDAY. LOW TEMPERATURES
LOOK TO REMAIN MILD (UPPER 40S TO LOW 50S) EXCEPT FOR MONDAY NIGHT
WITH THE CENTER OF THE HIGH RIGHT OVER THE AREA WHEN TEMPERATURES
COULD FALL TO AROUND 40 DEGREES.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 325 AM EDT SUN OCT 14 2012
UNSETTLED WEATHER WILL BE THE RULE...ESPECIALLY EARLY ON. A STRONG
UPPER LOW WILL MOVE INTO THE NORTHERN PLAINS WEDNESDAY AND THEN
TRACK INTO OUR REGION TOWARDS THE WEEKEND WITH SOME MODELS MOVING IT
ON TO THE EAST OVER THE WEEKEND. MODELS INDICATE A STRONG COLD
FRONT WILL MOVE ACROSS OUR REGION LATE WEDNESDAY NIGHT OR EARLY
THURSDAY. ON WEDNESDAY WE CAN EXPECT INCREASING CLOUDS WITH A CHANCE
OF PRECIP LATE ACROSS OUR NORTHWEST HALF. RAISED ALL BLEND
TEMPERATURES SLIGHTLY AS WARM ADVECTION WILL BE OCCURRING AHEAD OF
FRONT AND MEX NUMBERS WERE RUNNING ABOUT 5 DEGREES WARMER.
WILL CONTINUE LIKELY POPS MOST AREAS WEDNESDAY NIGHT AS FRONT MOVES
THROUGH AND THEN THERE IS SOME QUESTION ON THURSDAY AS A DRY SLOT
PUSHES INTO OUR WEST. FOR NOW WILL ACCEPT ALL BLEND POPS WHICH HAS
SLIGHT CHANCE POPS ACROSS OUR WEST AND CHANCE POPS FATHER EAST.
WILL CONTINUE LOW POPS MOST AREAS REST OF FORECAST AS UPPER LOW
ROTATES INTO OUR REGION. BY DAY 7 GFS HAS IT WELL TO OUR EAST WHILE
NEW EURO STILL HAS IT ACROSS OUR REGION. EXCEPT FOR RAISING MINS A
LITTLE THURSDAY NIGHT AND FRIDAY NIGHT WITH CLOUDS...DID NOT MAKE
ANY SIGNIFICANT CHANGE TO ALL BLEND TEMPERATURES FOR THE REST OF THE
EXTENDED.
&&
.AVIATION /DISCUSSION FOR THE 140900Z KIND TAF UPDATE/...
ISSUED AT 4330 AM EDT SUN OCT 14 2012
MINOR TWEAKS MADE TO KIND TAF PER OBSERVATIONS. NO OTHER CHANGES
NEEDED AT THIS TIME. PREVIOUS AVIATION DISCUSSION FOLLOWS...
A COLD FRONT WILL DROP SOUTHEAST ACROSS CENTRAL INDIANA AFTER 22Z
SUNDAY. RAPID REFRESH REFLECTIVITY SUGGESTS WIDESPREAD SHOWERS AND
THUNDERSTORMS WILL MOVE IN AHEAD OF THE FRONT AFTER 11Z.
MEANWHILE...RADAR TRENDS SUGGEST ANY AREA OF ADDITIONAL SHOWERS AND
PERHAPS THUNDERSTORMS WILL OVERSPREAD LAF BY ISSUANCE TIME.
SO...WILL GO WITH AT LEAST TEMPO SHOWERS THERE. COULD SEE SOME MVFR
CONDITIONS AT LAF OVERNIGHT AND THE OTHER SITES AFTER 11Z.
WINDS WILL ALSO BE AN ISSUE AS THE SURFACE PRESSURE GRADIENT
TIGHTENS. SOUTH WINDS WILL GUSTS TO NEAR 20 KNOTS OVERNIGHT AND
SUSTAINED TO 20 KNOTS WITH GUSTS NEAR 35 KNOTS AFTER 11Z. WINDS WILL
THEN BECOME SOUTHWEST AND THEN WEST BEHIND THE FRONT AFTER 22Z AND
DECREASE A BIT TO AROUND 15 KNOTS WITH 20 KNOT GUSTS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 11 AM THIS MORNING TO 8 PM EDT THIS EVENING FOR
INZ021-028>031-035>049-051>057-060>065-067>072.
&&
$$
SYNOPSIS...HOMANN
NEAR TERM...HOMANN
SHORT TERM...HOMANN
LONG TERM....JEH
AVIATION...MK/JEH
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
326 AM EDT SUN OCT 14 2012
.UPDATE...
THE SYNOPSIS...NEAR TERM...SHORT TERM AND LONG TERM SECTIONS HAVE BEEN
UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 325 AM EDT SUN OCT 14 2012
LOW PRESSURE CENTERED OUT IN THE PLAINS WILL CONTINUE TO MOVE
TOWARDS THE GREAT LAKES REGION FOR THE END OF THE WEEKEND. A STRONG
COLD FRONT ASSOCIATED WITH THIS SYSTEM WILL CROSS CENTRAL INDIANA
TODAY BRINGING THE CHANCE FOR SHOWERS AND THUNDERSTORMS TO THE
AREA...WITH THE POSSIBILITY OF STRONG TO SEVERE STORMS.
ADDITIONALLY...STRONG SOUTHERLY WINDS WITH GUSTS OVER 40 MPH ARE
POSSIBLE THIS AFTERNOON AS THE LOW CONTINUES TO STRENGTHEN.
HIGH PRESSURE WILL RETURN TO THE AREA ON MONDAY WITH DRY CONDITIONS
EXPECTED TO CONTINUE FOR ROUGHLY THE FIRST HALF OF THE WORK WEEK.
ANOTHER SYSTEM IS EXPECTED TO IMPACT THE REGION MIDWEEK BRINGING
ADDITIONAL CHANCES FOR PRECIPITATION HEADING INTO NEXT WEEKEND.
&&
.NEAR TERM /TODAY/...
ISSUED AT 325 AM EDT SUN OCT 14 2012
FORECAST CONCERNS FOR THE NEAR TERM CONTINUE TO BE THE STRONG WINDS
EXPECTED THIS AFTERNOON AS WELL AS THE POTENTIAL FOR SEVERE STORMS
AS A COLD FRONT PASSES THROUGH THE AREA.
WINDS ARE NOT AS STRONG THIS MORNING AS PREVIOUSLY FORECAST WITH THE
PRESSURE GRADIENT TAKING A BIT LONGER TO TIGHTEN UP AS THE LOW IS
SLOWER TO DEEPEN THAN EXPECTED. CURRENT THINKING IS THAT THE HIGHEST
SUSTAINED SPEEDS (20-25 MPH) AND ASSOCIATED GUSTS (40-45 MPH) WILL
NOT MIX DOWN UNTIL CLOSER TO 15Z...RATHER THAN AS EARLY AS 12Z.
THEREFORE...WILL DELAY THE START OF THE WIND ADVISORY TO 15Z. EVEN
WITH THE GRADIENT STAYING FAIRLY STRONG SUNDAY EVENING...WINDS
SHOULD BE ABLE TO SUBSIDE ENOUGH AFTER SUNSET SO AN END TIME OF
00Z MONDAY STILL SEEMS REASONABLE.
LATEST RADAR MOSAIC DISPLAYS A FAIRLY LARGE AREA OF PREFRONTAL
PRECIPITATION ACROSS NORTHERN AND WESTERN ILLINOIS SLIDING INTO
NORTHWEST INDIANA. THE HRRR SUGGESTS THIS SHOULD HOLD TOGETHER BUT
STAY JUST NORTH AND WEST OF THE FORECAST AREA. THIS MAKES SENSE DUE
TO THE LOCATION OF THE LEFT EXIT REGION OF THE 50-60 KT 850 MB JET.
THEREFORE...HAVE TRIMMED BACK POPS FOR THE MORNING HOURS..ESPECIALLY
ACROSS THE EASTERN ZONES.
MODELS DISPLAY SOME VARIABILITY IN TIMING THE ARRIVAL OF THE COLD
FRONT AND ITS ASSOCIATED PRECIPITATION. THE NAM AND ECMWF APPEAR TO
BE THE FASTEST WITH QPF ENCOMPASSING A MAJORITY OF THE FORECAST AREA
BY 12Z WHILE THE GFS APPEARS TO BE MORE IN LINE WITH THE HRRR.
REGARDLESS...ALL MODELS DEPICT THE BULK OF THE PRECIPITATION
IMPACTING THE AREA IN THE 18-00Z TIME FRAME SO HAVE HIT POPS THE
HARDEST DURING THE LATE AFTERNOON AND EARLY EVENING HOURS.
IN REGARDS TO SEVERE POTENTIAL...INSTABILITY LOOKS TO BE RESPECTABLE
WITH AROUND 500-750 J/KG TO WORK WITH BY MID TO LATE AFTERNOON.
HOWEVER...THE DYNAMICS APPEAR TO PROVIDE QUITE A BIT MORE SUPPORT
WITH THE FORCING FROM THE COLD FRONT BEING SUPPORTED BY THE UPPER
WAVE. WITH THE GFS DEPICTING 925 MB WINDS APPROACHING 60 KTS...ANY
DECENT STORMS THAT GET GOING SHOULD NOT HAVE TOO HARD OF A TIME
BRINGING SOME OF THAT DOWN TO THE SURFACE. THEREFORE...CONTINUE TO
EXPECT DAMAGING WINDS TO BE THE MAIN THREAT BUT THE POSSIBILITY FOR
SOME LARGE HAIL AND AN ISOLATED TORNADO OR TWO ARE NOT OUT OF THE
QUESTION.
WITH THE INFLUX OF WARM AND MOIST AIR CONTINUING AS SOUTHERLY WINDS
INCREASE...HIGH TEMPERATURES LOOK TO BE SIMILAR TO SATURDAY...IF NOT
A DEGREE OR TWO HIGHER...RANGING FROM THE LOW 70S ACROSS THE NORTH
TO THE MID 70S IN THE SOUTH.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
ISSUED AT 325 AM EDT SUN OCT 14 2012
WITH THE UPPER WAVE SLOW TO MOVE OUT OF THE REGION...HAVE HUNG ON TO
SMALL POPS FOR SUNDAY EVENING TO ACCOUNT FOR ANY LINGERING SHOWERS
OR THUNDERSTORMS. HIGH PRESSURE WILL THEN BUILD INTO THE REGION FOR
THE BEGINNING OF THE WORK WEEK ALLOWING DRY CONDITIONS TO RETURN FOR
THE REMAINDER OF THE PERIOD.
NORTHWEST WINDS FOLLOWING FRONTAL PASSAGE WILL ALLOW TEMPERATURES TO
DROP A BIT BUT HIGHS SHOULD BE NEAR NORMAL VALUES (MID 60S) WITH A
FAIR AMOUNT OF SUNSHINE ON BOTH MONDAY AND TUESDAY. LOW TEMPERATURES
LOOK TO REMAIN MILD (UPPER 40S TO LOW 50S) EXCEPT FOR MONDAY NIGHT
WITH THE CENTER OF THE HIGH RIGHT OVER THE AREA WHEN TEMPERATURES
COULD FALL TO AROUND 40 DEGREES.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 325 AM EDT SUN OCT 14 2012
UNSETTLED WEATHER WILL BE THE RULE...ESPECIALLY EARLY ON. A STRONG
UPPER LOW WILL MOVE INTO THE NORTHERN PLAINS WEDNESDAY AND THEN
TRACK INTO OUR REGION TOWARDS THE WEEKEND WITH SOME MODELS MOVING IT
ON TO THE EAST OVER THE WEEKEND. MODELS INDICATE A STRONG COLD
FRONT WILL MOVE ACROSS OUR REGION LATE WEDNESDAY NIGHT OR EARLY
THURSDAY. ON WEDNESDAY WE CAN EXPECT INCREASING CLOUDS WITH A CHANCE
OF PRECIP LATE ACROSS OUR NORTHWEST HALF. RAISED ALL BLEND
TEMPERATURES SLIGHTLY AS WARM ADVECTION WILL BE OCCURRING AHEAD OF
FRONT AND MEX NUMBERS WERE RUNNING ABOUT 5 DEGREES WARMER.
WILL CONTINUE LIKELY POPS MOST AREAS WEDNESDAY NIGHT AS FRONT MOVES
THROUGH AND THEN THERE IS SOME QUESTION ON THURSDAY AS A DRY SLOT
PUSHES INTO OUR WEST. FOR NOW WILL ACCEPT ALL BLEND POPS WHICH HAS
SLIGHT CHANCE POPS ACROSS OUR WEST AND CHANCE POPS FATHER EAST.
WILL CONTINUE LOW POPS MOST AREAS REST OF FORECAST AS UPPER LOW
ROTATES INTO OUR REGION. BY DAY 7 GFS HAS IT WELL TO OUR EAST WHILE
NEW EURO STILL HAS IT ACROSS OUR REGION. EXCEPT FOR RAISING MINS A
LITTLE THURSDAY NIGHT AND FRIDAY NIGHT WITH CLOUDS...DID NOT MAKE
ANY SIGNIFICANT CHANGE TO ALL BLEND TEMPERATURES FOR THE REST OF THE
EXTENDED.
&&
.AVIATION /DISCUSSION FOR THE 140600Z TAF ISSUANCE/...
ISSUED AT 1230 AM EDT SUN OCT 14 2012
A COLD FRONT WILL DROP SOUTHEAST ACROSS CENTRAL INDIANA AFTER 22Z
SUNDAY. RAPID REFRESH REFLECTIVITY SUGGESTS WIDESPREAD SHOWERS AND
THUNDERSTORMS WILL MOVE IN AHEAD OF THE FRONT AFTER 11Z.
MEANWHILE...RADAR TRENDS SUGGEST ANY AREA OF ADDITIONAL SHOWERS AND
PERHAPS THUNDERSTORMS WILL OVERSPREAD LAF BY ISSUANCE TIME.
SO...WILL GO WITH AT LEAST TEMPO SHOWERS THERE. COULD SEE SOME MVFR
CONDITIONS AT LAF OVERNIGHT AND THE OTHER SITES AFTER 11Z.
WINDS WILL ALSO BE AN ISSUE AS THE SURFACE PRESSURE GRADIENT
TIGHTENS. SOUTH WINDS WILL GUSTS TO NEAR 20 KNOTS OVERNIGHT AND
SUSTAINED TO 20 KNOTS WITH GUSTS NEAR 35 KNOTS AFTER 11Z. WINDS WILL
THEN BECOME SOUTHWEST AND THEN WEST BEHIND THE FRONT AFTER 22Z AND
DECREASE A BIT TO AROUND 15 KNOTS WITH 20 KNOT GUSTS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 11 AM THIS MORNING TO 8 PM EDT THIS EVENING FOR
INZ021-028>031-035>049-051>057-060>065-067>072.
&&
$$
SYNOPSIS...HOMANN
NEAR TERM...HOMANN
SHORT TERM...HOMANN
LONG TERM....JEH
AVIATION...MK
AREA FORECAST DISCUSSION
NWS GOODLAND KS
223 PM MDT SUN OCT 14 2012
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 1251 PM MDT SUN OCT 14 2012
LATEST WV IMAGERY AND RUC H5 ANALYSIS SHOW RIDGE ACROSS NORTHERN
ROCKIES WITH LARGE SCALE TROUGH STILL IN PLACE OVER UPPER
MISSISSIPPI RIVER VALLEY. NW FLOW REMAINS IN PLACE ACROSS THE PLAINS
BETWEEN THESE FEATURES. AT THE SURFACE HIGH PRESSURE IS IN PLACE
OVER EASTERN COLORADO...WITH A LARGE AREA OF LOW PRESSURE OVER THE
CENTRAL MISSISSIPPI RIVER VALLEY. BETWEEN THESE FEATURES...TIGHTENED
PRESSURE GRADIENT OVER THE CWA HAS LED TO GUSTY WINDS BETWEEN 25 AND
30 MPH. THESE WINDS SHOULD DIMINISH AROUND SUNSET WITH AN END OF
DAYTIME MIXING.
A SURFACE TROUGH WILL DEVELOP ALONG THE KS/CO STATE LINE BY EARLY
MONDAY MORNING...WITH GRADIENT RELAXING ACROSS THE CWA. RESULT WILL
BE DEVELOPMENT OF LIGHT SW WINDS AND WAA AT H85. DESPITE WARMER
TEMPS ALOFT...CLEAR SKIES AND CALM WINDS WILL SUPPORT GOOD
RADIATIONAL COOLING OVERNIGHT. MOST LOCATIONS SHOULD SEE LOWS IN THE
LOW TO MID 40S...AND UPPER 30S AT TRADITIONAL COLD SPOTS. H5 RIDGE
WILL CONTINUE TO BUILD EAST OVERNIGHT AND SHOULD BE OVER CWA BY
EARLY MONDAY MORNING. WITH LARGE SCALE SUBSIDENCE IN PLACE MOSTLY
CLEAR SKIES AND DRY CONDITIONS SHOULD PREVAIL THROUGH MONDAY.
AIR MASS WILL CONTINUE TO MODERATE THROUGH MONDAY AFTERNOON...WITH
H85 TEMPS ABOUT 5-7C WARMER THAN THIS AFTERNOON. THIS SHOULD
SUPPORT AFTERNOON HIGH TEMPERATURES IN THE UPPER 70S TO LOW 80S
ACROSS THE CWA.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 217 PM MDT SUN OCT 14 2012
LATE MONDAY NIGHT AN UPPER LEVEL SHORT WAVE TROUGH AND SURFACE
TROUGH/WEAK COLD FRONT WILL MOVE THROUGH THE NORTHEAST HALF OF THE
AREA. SOUNDINGS SHOW LITTLE MOISTURE TO WORK WITH SO AM ONLY
ANTICIPATING A FEW CLOUDS DURING THE OVERNIGHT HOURS.
TUESDAY A SHORT WAVE RIDGE AND SURFACE HIGH FOLLOW THE SURFACE
TROUGH INTO THE AREA. WINDS TURN TO THE SOUTHWEST AS THE RIDGE
BUILDS IN CAUSING TEMPERATURES TO WARM WELL ABOVE NORMAL.
TUESDAY NIGHT A STRONGER COLD FRONT MOVES INTO THE AREA DURING THE
EVENING...AND EXITS THE AREA DURING THE OVERNIGHT HOURS. THERE IS
SOME 700-500MB MOISTURE TO WORK WITH...HOWEVER A DRY LAYER WILL
STILL EXIST BELOW 700MB. MODELS DISAGREE WITH THE 500 AND 300MB
JET PLACEMENT BEHIND THE FRONT...BUT THE MAJORITY OF THE MODELS
INDICATE THE LEFT EXIT REGION OF THE JET MAY BE IN A FAVORABLE
LOCATION FOR THE NORTHERN HALF OF THE AREA TO RECEIVE PRECIP. THE
DOWNFALL IS THE DRY LAYER PRESENT BETWEEN 700MB AND THE SURFACE
WILL PREVENT ANY PRECIP THAT MAY FORM FROM REACHING THE GROUND.
UPPER LEVEL LIFT IMPROVES BEHIND THE FRONT AS A DEEPENING LONG
WAVE TROUGH MOVES IN...BUT SOUNDINGS SHOW THE ENVIRONMENT DRYING
OUT BEHIND THE FRONT. IN ADDITION GEFS AND SREF MEMBERS PLACE THE
PRECIP NORTH OF THE TRI-STATE AREA. WITH UNCERTAINTIES REGARDING THE
AMOUNT OF MOISTURE AVAILABLE WILL ONLY PLACE IN SILENT CHANCES FOR
THE AREA.
FOR THE WEDNESDAY THROUGH SUNDAY PERIOD THE FORECAST WILL CONTINUE
TO BE DRY. THE LONG WAVE TROUGH WILL CONTINUE TO DEEPEN WEDNESDAY
AS IT PROGRESSES EAST...BECOMING A CLOSED LOW OVER THE UPPER
MIDWEST AND LINGERING THERE THROUGH SATURDAY. MEANWHILE NORTHWEST
WINDS WILL STRENGTHEN WEDNESDAY BEHIND THE COLD FRONT FROM TUESDAY
NIGHT. THURSDAY THE WINDS WILL STRENGTHEN FURTHER DUE TO 40-50KT
850MB WINDS WINDS MIXING DOWN. WEDNESDAY AND THURSDAY AFTERNOON
THE FIRE DANGER WILL INCREASE ACROSS THE AREA DUE TO WINDS GUSTING
TO 35 MPH ON WEDNESDAY...45 MPH ON THURSDAY WITH RELATIVE
HUMIDITIES AROUND 20 PERCENT BOTH DAYS. OTHERWISE TEMPERATURES
WILL BE NEAR TO BELOW NORMAL THROUGH FRIDAY THEN ABOVE NORMAL
TEMPERATURES RETURN FOR THE WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1109 AM MDT SUN OCT 14 2012
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT KGLD AND KMCK.
NW WINDS WILL GUST BETWEEN 25-30KT AT BOTH TERMINALS THIS
AFTERNOON. WINDS WILL DECREASE AROUND SUNSET AND SHIFT TO THE
SOUTHWEST AND THE SURFACE TROUGH OVER EASTERN COLORADO MOVES EAST
AND THE GRADIENT RELAXES.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JTL
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1251 PM MDT SUN OCT 14 2012
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 1251 PM MDT SUN OCT 14 2012
LATEST WV IMAGERY AND RUC H5 ANALYSIS SHOW RIDGE ACROSS NORTHERN
ROCKIES WITH LARGE SCALE TROUGH STILL IN PLACE OVER UPPER
MISSISSIPPI RIVER VALLEY. NW FLOW REMAINS IN PLACE ACROSS THE PLAINS
BETWEEN THESE FEATURES. AT THE SURFACE HIGH PRESSURE IS IN PLACE
OVER EASTERN COLORADO...WITH A LARGE AREA OF LOW PRESSURE OVER THE
CENTRAL MISSISSIPPI RIVER VALLEY. BETWEEN THESE FEATURES...TIGHTENED
PRESSURE GRADIENT OVER THE CWA HAS LED TO GUSTY WINDS BETWEEN 25 AND
30 MPH. THESE WINDS SHOULD DIMINISH AROUND SUNSET WITH AN END OF
DAYTIME MIXING.
A SURFACE TROUGH WILL DEVELOP ALONG THE KS/CO STATE LINE BY EARLY
MONDAY MORNING...WITH GRADIENT RELAXING ACROSS THE CWA. RESULT WILL
BE DEVELOPMENT OF LIGHT SW WINDS AND WAA AT H85. DESPITE WARMER
TEMPS ALOFT...CLEAR SKIES AND CALM WINDS WILL SUPPORT GOOD
RADIATIONAL COOLING OVERNIGHT. MOST LOCATIONS SHOULD SEE LOWS IN THE
LOW TO MID 40S...AND UPPER 30S AT TRADITIONAL COLD SPOTS. H5 RIDGE
WILL CONTINUE TO BUILD EAST OVERNIGHT AND SHOULD BE OVER CWA BY
EARLY MONDAY MORNING. WITH LARGE SCALE SUBSIDENCE IN PLACE MOSTLY
CLEAR SKIES AND DRY CONDITIONS SHOULD PREVAIL THROUGH MONDAY.
AIR MASS WILL CONTINUE TO MODERATE THROUGH MONDAY AFTERNOON...WITH
H85 TEMPS ABOUT 5-7C WARMER THAN THIS AFTERNOON. THIS SHOULD
SUPPORT AFTERNOON HIGH TEMPERATURES IN THE UPPER 70S TO LOW 80S
ACROSS THE CWA.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 200 AM MDT SUN OCT 14 2012
THE EXTENDED PERIOD IS EXPECTED TO BE DRY FOLLOWING A
MOISTURE-LACKING FRONTAL PASSAGE ON WEDNESDAY. THIS COLD FRONT IS
EXPECTED TO PUSH THROUGH EARLY WEDNESDAY...ENDING THE RUN OF MILD
TEMPERATURES EARLIER IN THE WEEK. BEHIND THE FRONT THERE WILL BE
STRONG NORTHWEST WINDS WEDNESDAY AND THURSDAY WITH GUSTS UP TO 35
MPH. TEMPERATURES OVER THE PERIOD WILL BE NEAR NORMAL TO ABOVE
NORMAL AS AN UPPER LEVEL RIDGE DEVELOPS OVER THE ROCKIES LATE IN
THE WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1109 AM MDT SUN OCT 14 2012
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT KGLD AND KMCK.
NW WINDS WILL GUST BETWEEN 25-30KT AT BOTH TERMINALS THIS
AFTERNOON. WINDS WILL DECREASE AROUND SUNSET AND SHIFT TO THE
SOUTHWEST AND THE SURFACE TROUGH OVER EASTERN COLORADO MOVES EAST
AND THE GRADIENT RELAXES.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JJM
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1058 PM MDT SAT OCT 13 2012
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 236 PM MDT SAT OCT 13 2012
LATEST WV IMAGERY AND RUC H5 ANALYSIS SHOW STRONG UPPER LOW CENTERED
ALONG KS/CO BORDER WITH AXIS OF MOISTURE ON BACK SIDE OF UPPER LOW
BEGINNING TO MOVE FROM CENTRAL INTO EASTERN COLORADO. RADAR
CURRENTLY INDICATED SHOWERS/ISOLATED THUNDERSTORMS DEVELOPING OVER
THE WESTERN PART OF OUR CWA ALONG KS/CO STATE LINE. THIS IS AHEAD OF
H7 TROUGH AND ALONG NORTHWESTERN AXIS OF STEEP LAPSE RATES.
LATEST HRRR AND RUC BOTH SHOW SHOWERS AND THUNDERSTORMS CONTINUING
TO DEVELOP EASTWARD ACROSS THE REST OF THE CWA THROUGH THE EARLY
EVENING. THIS ACTIVITY SHOULD DIMINISH AFTER SUNSET AS WE LOOSE THE
STEEP LOW LEVEL LAPSE RATES. WITH SCATTERED COVERAGE...AND LIGHT
NATURE OF MOST OF THIS ACTIVITY...PRECIPITATION SHOULD BE LIGHT.
DESPITE MINIMAL CAPE VALUES IN THE 100-500 J/KG RANGE AND WEAK
0-6KM SHEAR...IT WILL NOT TAKE MUCH TO PRODUCE SEVERE HAIL WITH
-20C HEIGHTS AROUND 15-18KFT ACROSS THE CWA. WITH LOW LCL VALUES
AROUND 1500 KFT AND FAVORABLE AREA BENEATH UPPER LOW WHERE
DIFFERENTIAL HEATING AXIS/SURFACE TROUGH OVERLAP...I CANT RULE OUT
FUNNEL/LANDSPOUT FORMATION WITH THIS ACTIVITY THIS AFTERNOON/EARLY
EVENING. CONSIDERING ABSENCE OF DISTINCT SURFACE BOUNDARY...AND
LOCATION OF BEST SURFACE VORTICITY FURTHER NORTH...THIS THREAT
SEEMS TO BE MINIMAL AT BEST.
THE UPPER LOW WILL SHIFT EAST OF THE CWA BY 06Z TONIGHT...WITH
SHORTWAVE RIDGING AND LARGE SCALE SUBSIDENCE OVERSPREADING THE AREA
BY SUNDAY. WITH SIMILAR H85 TEMPS AND NW WIND PERSISTING...TEMPERATURES
ON SUNDAY SHOULD AT LEAST BE SIMILAR TO THIS AFTERNOON WITH HIGHS
IN THE 70S FOR MOST OF THE AREA.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 236 PM MDT SAT OCT 13 2012
SUNDAY NIGHT THROUGH MONDAY NIGHT DRY NORTHWEST UPPER LEVEL FLOW
WILL CONTINUE OVER THE AREA. A SHORT WAVE TROUGH MOVES THROUGH THE
FLOW LATE MONDAY NIGHT ACCOMPANYING A SURFACE TROUGH/WEAK COLD
FRONT. POINT SOUNDINGS INDICATE THE UPPER LEVELS MOISTEN AS THE
SHORT WAVE MOVES THROUGH...SO AM ONLY EXPECTING A FEW CLOUDS TO
DEVELOP DURING THE OVERNIGHT HOURS.
TUESDAY THROUGH SATURDAY WILL REMAIN DRY. A COLD FRONT AND UPPER
LEVEL SHORT WAVE TROUGH WILL MOVE THROUGH WEDNESDAY. BEHIND THE
COLD FRONT WINDS WILL BECOME GUSTY DURING THE AFTERNOON. MOISTURE
WILL REMAIN NORTH OF THE AREA...SO AM NOT ANTICIPATING ANY PRECIP
WITH THE FRONT. THERE MAY BE SOME LIFT FROM THE LEFT EXIT OF THE 500
MB JET...BUT MODELS DISAGREE WITH THE JET PLACEMENT BEHIND THE
FRONT. WITH THE MOISTURE GENERALLY NORTH OF THE AREA AND THE
POSITION OF THE JET IN QUESTION...WILL LEAVE THE FRONTAL PASSAGE DRY.
OTHERWISE TEMPERATURES WILL BE 10 DEGREES ABOVE NORMAL AHEAD THE
COLD FRONT...WITH NEAR NORMAL TEMPERATURES BEHIND THE FRONT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1047 PM MDT SAT OCT 13 2012
VFR CONDITIONS EXPECTED FOR THE NEXT 24 HOURS AT KGLD AND KMCK AS
CLEARING OCCURS BEHND THE EXITING LOW. REDEVELOPMENT OF A BREEZY
NORTH WIND AND CUMULUS CAN BE EXPECTED FOR A FEW HOURS TUESDAY
AFTERNOON.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JTL
AVIATION...FS
AREA FORECAST DISCUSSION...UPDATED
NWS PADUCAH KY
1138 PM CDT SAT OCT 13 2012
.UPDATE...
ISSUED AT 1133 PM CDT SAT OCT 13 2012
UPDATED AVIATION SECTION FOR THE 06Z TAF ISSUANCE.
&&
UPDATED FORECAST TO RAISE POPS TO CATEGORICAL IN PARTS OF SE
MISSOURI AND SW ILLINOIS LATE TONIGHT. RUC MODEL INDICATES THAT
WIDESPREAD RAIN AND STORMS IN THE WARM CONVEYOR BELT OVER
NORTHERN/WESTERN MISSOURI WILL OVERSPREAD SE MISSOURI AND SW
ILLINOIS AFTER 06Z. THE AXIS OF THE LOW LEVEL JET WILL BE ORIENTED
ALONG OR JUST WEST OF THE MISSISSIPPI RIVER BY 12Z...WITH 50 TO 60
KNOTS IN THE 850/900 MB LAYER. THOUGH INSTABILITY WILL BE MARGINAL
AND ELEVATED...A FEW DAMAGING WIND GUSTS ARE POSSIBLE GIVEN THE WIND
FIELDS ALOFT AND STRONG FORCING FOR CONVECTION.
ADDED MENTION OF GRADIENT WIND GUSTS FROM 30 TO 40 MPH TO THE HWO.
BUFKIT ANALYSIS FROM BOTH GFS/NAM INDICATES SUFFICIENT MIXING ON
SUNDAY TO GET SOME SURFACE GUSTS TO NEAR 40 MPH. DEGREE OF CLEARING
IN THE WAKE OF THE MORNING CONVECTION WILL PLAY A LARGE ROLE IN WIND
GUST POTENTIAL...AS WELL AS POTENTIAL FOR AFTERNOON STORMS.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 310 PM CDT SAT OCT 13 2012
DID NOT MAKE ANY DRASTIC CHANGES TO THE GOING FORECAST. ECMWF AND
GEM ARE BOTH A BIT FASTER WITH THE ONSET OF PRECIP THAN THE GFS
AND NAM...BRINGING SHOWERS AND THUNDERSTORMS INTO OUR FAR WESTERN
COUNTIES BY 06Z SUNDAY. OVERALL...THE TIMING DIFFERENCES ARE
MINOR...AND WENT WITH LIKELY POPS FOR THE WESTERN HALF OF THE PAH
FORECAST AREA BY 12Z SUNDAY. THE BEST CHANCES FOR THE WESTERN HALF
OF THE FA WILL BE THROUGH THE MORNING INTO THE EARLY
AFTERNOON...AND THE EASTERN HALF FROM MID MORNING THROUGH MID
AFTERNOON. ALL OF OUR COUNTIES HAVE AT LEAST A FEW HOURS OF LIKELY
POPS.
ECMWF AND GFS SHOW LI`S OF -1 TO -3...AND CAPE VALUES OF
700 TO 1100 J/KG...MAINLY FROM 12Z TO 18Z SUNDAY. NAM CONTINUES
SOME IMPRESSIVE LI AND CAPE VALUES /-3 TO -5 AND 1000 TO 1300
J/KG/ INTO THE AFTERNOON HOURS...WHEN ECMWF AND GFS HAVE ALREADY
PUSHED BEST LIFT/INSTABILITY EAST OF OUR COUNTIES. BASED ON THE
FRONT/UPPER TROF STILL IN WESTERN PORTIONS OF THE FA BY MID
AFTERNOON AND SPC DAY 2 SLIGHT RISK FOR ALL BUT FAR WESTERN
PORTIONS OF OUR FA...NAM LOOKS LIKE A BETTER BET...SO SHOULD SEE
SOME DECENT ACTIVITY THROUGH THE DAY...WITH SOME POTENTIAL FOR
SEVERE STORMS.
THE OTHER ISSUE FOR SUNDAY IS WINDS. MODELS SHOW A VERY TIGHT
PRESSURE GRADIENT TONIGHT AND ESPECIALLY SUNDAY ALONG AND AHEAD OF
THE FRONT. SOUTH TO SOUTHWEST WINDS WILL PICK BACK UP TO 10 TO 15
KTS LATE TONIGHT...THEN INCREASE TO 15 TO 25 KTS WITH GUSTS OF 30
TO 35 KTS FROM 12Z TO 22Z. THIS KEEPS US BELOW WIND ADVISORY
CRITERIA...BUT WILL CONTINUE WITH AN SPS TO HEIGHTEN AWARENESS.
BEYOND SUNDAY...HIGH PRESSURE WILL BUILD INTO THE CENTRAL U.S. FOR
SUNDAY NIGHT THROUGH MONDAY NIGHT. AFTER ABOVE NORMAL TEMPERATURES
ON SUNDAY...NORTHWEST WINDS BEHIND THE FRONT WILL BRING
TEMPERATURES BACK TO NEAR TO EVEN SLIGHTLY BELOW NORMAL TEMPS.
.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 310 PM CDT SAT OCT 13 2012
THE BIG EVENT OF THE LONG TERM IS THE MID WEEK SYSTEM SO WE WILL
FOCUS ON THAT HERE. POSITIVE MODEL INDICATIONS ARE THAT BOTH THE
EURO AND THE GFS ARE SYNCHRONIZING THE INTRODUCTORY PCPN TIMING AS
THE FRONT APPROACHES THE DOORSTEP OF THE FA BY 00Z THU. IT WILL
ENCOUNTER MINOR INSTABILITY...MAINLY ELEVATED...AS BOTH MODELS AGREE
THE BEST CHANCE OF PCPN COMES WITH/POST FROPA OVERNIGHT WED NIGHT.
WE LIKE THE ALLBLENDS LIKELY CAT POPS AS A STARTING POINT AND COULD
BE GOING UP FROM THERE...BUT WITH LATE DAY 5 WE`LL SEE HOW COLLAB
PLAYS OUT ON THAT.
MODEL DIFFERENCES START WITH THE DEPARTURE OF THE SYSTEM ON
THURSDAY. THE EURO IS MORE AMPLIFIED AND CUTS OFF/DEEPENS THE
LOW...OCCLUDING THE FRONT/LINGERING THE POPS. THE GFS LIKEWISE HAS A
ROBUST/DEEPENING OF THE LOW BUT IS MORE PROGRESSIVE WITH IT ACTUALLY
PASSING AND SWEEPING EASTWARD TO THE EAST COAST. THE ALLBLENDS TENDS
BETWEEN THE TWO WITH LEAN TOWARD THE GFS AND WE THINK THAT IS
REASONABLE UNLESS/UNTIL MORE SUPPORT IS YIELDED TOWARD THE EURO.
TEMPS...70S/50S LOOK REASONABLE AHEAD OF THE FRONT...WITH 60S/40S
AFTER ITS PASSAGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1133 PM CDT SAT OCT 13 2012
VFR CONDITIONS EXPECTED AT KCGI/KPAH THROUGH 09-10Z...MVFR CIGS/VSBYS
AND TSRA THROUGH 15-16Z...THEN VFR AGAIN. AT KEVV/KOWB VFR CONDITIONS
EXPECTED THROUGH 13-14Z...MVFR CIGS/VSBYS AND TSRA THROUGH 19-20Z...THEN
VFR. SOUTHERLY WINDS AROUND 10 KTS WILL PICK UP OUT OF THE SOUTH
SOUTHWEST AFT 10Z AT 15-20 KTS WITH GUSTS TO 25-30 KTS...THEN VEER
AROUND TO THE WEST AT 10-15 KTS AFT 00Z.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
AVIATION...JP
PUBLIC/GRIDS...MY
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1000 PM EDT MON OCT 15 2012
.SYNOPSIS...
EASTWARD BUILDING HIGH PRESSURE FROM WISCONSIN WILL END ANY
REMAINING SHOWERS OVERNIGHT...AND PROMOTE SUNSHINE ACROSS THE
UPPER OHIO VALLEY TUESDAY AND WEDNESDAY.
&&
.NEAR TERM /THROUGH TUESDAY/...
THE TREND IN RECENT RADAR AND SURFACE DATA SHOWS CONTINUED
DECREASE IN THE COVERAGE OF LIGHT RAIN SHOWERS ACROSS THE UPPER
OHIO VALLEY.
SO CONCUR WITH RECENT RAP AND SREF MODEL OUTPUT THAT THE REMAINING
SHOWERS WILL HAVE LARGELY DISSIPATED OVER THE LOWER ELEVATIONS BY
AROUND MIDNIGHT...AND OVER THE APPALACHIAN MOUNTAINS BY 3 AM.
LIKEWISE...NAM MODEL PROFILES SHOW CLOUDS DISSIPATING BY MORNING
TO YIELD CONSIDERABLE SUNSHINE DAYTIME TUESDAY...AS HIGH PRESSURE
BUILDS EAST FROM WISCONSIN.
SURFACE WINDS WILL CONTINUE TO SLOW TO SPEEDS MAINLY BETWEEN 5 AND
10 MPH BY LATE TONIGHT.
CONTINUED FORECAST OF TEMPERATURES UP TO 5 DEGREES COLDER THAN
NORMAL PER BLEND OF RECENT NAM AND GFS MOS.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
RECENT SREF MODEL OUTPUT SHOWS DRY HIGH PRESSURE WILL DOMINATE
THROUGH WEDNESDAY...WITH GRADUALLY MODERATING
TEMPERATURES...PARTICULARLY AS LOW LEVEL FLOW TURNS SOUTHERLY BY
WEDNESDAY.
CLOUDS WILL BEGIN TO INCREASE WEDNESDAY NIGHT AS A COLD
FRONT APPROACHES AHEAD OF A DEVELOPING UPPER LEVEL LOW ACROSS THE
WESTERN GREAT LAKES.
FRONT IS EXPECTED TO BRING SHOWERS FOR THURSDAY. AT THIS JUNCTURE
HAVE FORECASTED CHANCE POPS...AS SOME MEMBER MODELS OVER THE LAST
SEVERAL RUNS HAVE HAD VARIABLE SOLUTIONS WITH FRONTAL PROGRESSION
DETAILS.
FORECASTED TEMPERATURES USING AN EVEN BLEND OF NAM AND GFS MOS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
WHILE THE MODELS AGREE ON A VERY AMPLIFIED UPPER LEVEL
PATTERN...WITH A CUTOFF LOW SITUATED NEAR THE GREAT LAKES...THE
ACTUAL POSITION AND STRENGTH VARIES.
THE SOLUTIONS THEN DIVERGE EVEN FURTHER INTO THE PERIOD WITH THE
06Z/12Z GFS EJECTING THE UPPER LOW AND BRINGING A RETURN OF ZONAL
FLOW MUCH FASTER THAN THE SLOWER AND DEEPER 00Z ECMWF. THE CMC IS
BETWEEN THE TWO AND SEEMS TO BE AT LEAST A GOOD COMPROMISE IN THE
UPPER LEVELS THROUGH THIS PERIOD.
FOR NOW...WILL EMPLOY A BLEND OF THE MODELS...SIMILARLY TO WHAT HPC
HAS CONSTRUCTED THROUGH THE PERIOD...KEEPING AN UNSETTLED PATTERN
THROUGH SATURDAY BEFORE SHOWING A DRY OUT FOR SUNDAY AND MONDAY.
CONTINUED FORECAST OF TEMPERATURES SLIGHTLY COOLER THAN NORMAL
THROUGH THE PERIOD.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
CONSIDERING W-NW WINDS MAY CONTINUE FOR THE NEXT SEVERAL
HOURS...THINK THAT MVFR COLD POOL STRATOCUMULUS CEILINGS MAY
LINGER UNTIL CLOUDS DISSIPATE BY 11Z...ALBEIT PERHAPS SOONER FOR
KPIT AND WEST.
IF ZZV DOES CLEAR OUT...MVFR FOG CAN OCCUR NEAR DAYBREAK.
EASTWARD BUILDING HIGH PRESSURE WILL PROMOTE VFR TUESDAY.
.OUTLOOK.../TUESDAY THROUGH SATURDAY/...
HIGH PRESSURE WILL CONTINUE VFR CONDITIONS INTO WEDNESDAY. THE
NEXT CHANCE FOR RESTRICTIONS WILL BE WITH THE FRONTAL PASSAGE
EXPECTED THURSDAY. AN UNSETTLED PATTERN BEHIND THE FRONT COULD
KEEP CHANCES FOR RESTRICTIONS THROUGH THE FIRST HALF OF THE
WEEKEND.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
759 PM EDT MON OCT 15 2012
.SYNOPSIS...
EASTWARD BUILDING HIGH PRESSURE FROM WISCONSIN WILL END ANY
REMAINING SHOWERS OVERNIGHT AND PROMOTE SUNSHINE ACROSS THE UPPER
OHIO VALLEY TUESDAY AND WEDNESDAY.
&&
.NEAR TERM /THROUGH TUESDAY/...
RECENT RADAR AND SURFACE DATA CONTINUE TO SHOW SCATTERED LIGHT
RAIN SHOWERS...INDUCED BY AN EASTBOUND COLD UPPER LEVEL
TROUGH...MOVING SOUTHEASTWARD ACROSS THE UPPER OHIO VALLEY THIS
EVENING.
HOWEVER...CONCUR WITH RECENT RAP AND SREF MODEL OUTPUT THAT THE
REMAINING SHOWERS WILL HAVE LARGELY DISSIPATED OVER THE LOWER
ELEVATIONS BY AROUND MIDNIGHT...AND OVER THE APPALACHIAN MOUNTAINS
BY 3 AM.
NAM MODEL PROFILES THEN SHOW CLOUDS DISSIPATING BY MORNING TO
YIELD CONSIDERABLE SUNSHINE DAYTIME TUESDAY...AS HIGH PRESSURE
BUILDS EAST FROM WISCONSIN.
SURFACE WINDS WILL CONTINUE TO SLOW TO SPEEDS MAINLY BETWEEN 5 AND
10 MPH BY LATE TONIGHT.
CONTINUED FORECAST OF TEMPERATURES UP TO 5 DEGREES COLDER THAN
NORMAL PER BLEND OF RECENT NAM AND GFS MOS.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
RECENT SREF MODEL OUTPUT SHOWS DRY HIGH PRESSURE WILL DOMINATE
THROUGH WEDNESDAY...WITH GRADUALLY MODERATING
TEMPERATURES...PARTICULARLY AS LOW LEVEL FLOW TURNS SOUTHERLY BY
WEDNESDAY.
CLOUDS WILL BEGIN TO INCREASE WEDNESDAY NIGHT AS A COLD
FRONT APPROACHES AHEAD OF A DEVELOPING UPPER LEVEL LOW ACROSS THE
WESTERN GREAT LAKES.
FRONT IS EXPECTED TO BRING SHOWERS FOR THURSDAY. AT THIS JUNCTURE
HAVE FORECASTED CHANCE POPS...AS SOME MEMBER MODELS OVER THE LAST
SEVERAL RUNS HAVE HAD VARIABLE SOLUTIONS WITH FRONTAL PROGRESSION
DETAILS.
FORECASTED TEMPERATURES USING AN EVEN BLEND OF NAM AND GFS MOS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
WHILE THE MODELS AGREE ON A VERY AMPLIFIED UPPER LEVEL
PATTERN...WITH A CUTOFF LOW SITUATED NEAR THE GREAT LAKES...THE
ACTUAL POSITION AND STRENGTH VARIES.
THE SOLUTIONS THEN DIVERGE EVEN FURTHER INTO THE PERIOD WITH THE
06Z/12Z GFS EJECTING THE UPPER LOW AND BRINGING A RETURN OF ZONAL
FLOW MUCH FASTER THAN THE SLOWER AND DEEPER 00Z ECMWF. THE CMC IS
BETWEEN THE TWO AND SEEMS TO BE AT LEAST A GOOD COMPROMISE IN THE
UPPER LEVELS THROUGH THIS PERIOD.
FOR NOW...WILL EMPLOY A BLEND OF THE MODELS...SIMILARLY TO WHAT HPC
HAS CONSTRUCTED THROUGH THE PERIOD...KEEPING AN UNSETTLED PATTERN
THROUGH SATURDAY BEFORE SHOWING A DRY OUT FOR SUNDAY AND MONDAY.
CONTINUED FORECAST OF TEMPERATURES SLIGHTLY COOLER THAN NORMAL
THROUGH THE PERIOD.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
THINK THAT RECENT AVIATION GUIDANCE IS TOO OPTIMISTIC WITH
FORECAST. CONSIDERING W-NW WINDS THAT ARE EXPECTED TO CONTINUE FOR
THE NEXT SEVERAL HOURS...THINK THAT MVFR COLD POOL STRATOCUMULUS
CEILINGS WILL ALSO CONTINUE FOR SEVERAL MORE HOURS. HAVE GONE
SLIGHTLY MORE OPTIMISTIC THAN PREVIOUS FORECAST...GOING WITH
2000FT CEILINGS INSTEAD OF 1500FT CEILINGS...BUT NOT A HIGH
CONFIDENCE CHANGE IN FORECAST. EXPECT CLOUDS TO DISSIPATE BY 08Z-
11Z...PERHAPS SOONER FOR KPIT AND WEST. ZZV IS LIKELY THE ONLY
PLACE THAT WILL COMPLETELY CLEAR OUT...AND THINK THAT MVFR FOG
WILL OCCUR NEAR DAYBREAK.
EASTWARD BUILDING HIGH PRESSURE WILL PROMOTE VFR TUESDAY.
.OUTLOOK.../TUESDAY THROUGH SATURDAY/...
HIGH PRESSURE WILL CONTINUE VFR CONDITIONS INTO WEDNESDAY. THE
NEXT CHANCE FOR RESTRICTIONS WILL BE WITH THE FRONTAL PASSAGE
EXPECTED THURSDAY. AN UNSETTLED PATTERN BEHIND THE FRONT COULD
KEEP CHANCES FOR RESTRICTIONS THROUGH THE FIRST HALF OF THE
WEEKEND.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
714 PM EDT MON OCT 15 2012
.SYNOPSIS...
EASTWARD BUILDING HIGH PRESSURE FROM WISCONSIN WILL END ANY
REMAINING SHOWERS OVERNIGHT AND PROMOTE SUNSHINE ACROSS THE UPPER
OHIO VALLEY TUESDAY AND WEDNESDAY.
&&
.NEAR TERM /THROUGH TUESDAY/...
RECENT RADAR AND SURFACE DATA CONTINUE TO SHOW SCATTERED LIGHT
RAIN SHOWERS...INDUCED BY AN EASTBOUND COLD UPPER LEVEL
TROUGH...MOVING SOUTHEASTWARD ACROSS THE UPPER OHIO VALLEY THIS
EVENING.
HOWEVER...CONCUR WITH RECENT RAP AND SREF MODEL OUTPUT THAT THE
REMAINING SHOWERS WILL HAVE LARGELY DISSIPATED OVER THE LOWER
ELEVATIONS BY AROUND MIDNIGHT...AND OVER THE APPALACHIAN MOUNTAINS
BY 3 AM.
NAM MODEL PROFILES THEN SHOW CLOUDS DISSIPATING BY MORNING TO
YIELD CONSIDERABLE SUNSHINE DAYTIME TUESDAY...AS HIGH PRESSURE
BUILDS EAST FROM WISCONSIN.
SURFACE WINDS WILL CONTINUE TO SLOW TO SPEEDS MAINLY BETWEEN 5 AND
10 MPH BY LATE TONIGHT.
CONTINUED FORECAST OF TEMPERATURES UP TO 5 DEGREES COLDER THAN
NORMAL PER BLEND OF RECENT NAM AND GFS MOS.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
RECENT SREF MODEL OUTPUT SHOWS DRY HIGH PRESSURE WILL DOMINATE
THROUGH WEDNESDAY...WITH GRADUALLY MODERATING
TEMPERATURES...PARTICULARLY AS LOW LEVEL FLOW TURNS SOUTHERLY BY
WEDNESDAY.
CLOUDS WILL BEGIN TO INCREASE WEDNESDAY NIGHT AS A COLD
FRONT APPROACHES AHEAD OF A DEVELOPING UPPER LEVEL LOW ACROSS THE
WESTERN GREAT LAKES.
FRONT IS EXPECTED TO BRING SHOWERS FOR THURSDAY. AT THIS JUNCTURE
HAVE FORECASTED CHANCE POPS...AS SOME MEMBER MODELS OVER THE LAST
SEVERAL RUNS HAVE HAD VARIABLE SOLUTIONS WITH FRONTAL PROGRESSION
DETAILS.
FORECASTED TEMPERATURES USING AN EVEN BLEND OF NAM AND GFS MOS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
WHILE THE MODELS AGREE ON A VERY AMPLIFIED UPPER LEVEL
PATTERN...WITH A CUTOFF LOW SITUATED NEAR THE GREAT LAKES...THE
ACTUAL POSITION AND STRENGTH VARIES.
THE SOLUTIONS THEN DIVERGE EVEN FURTHER INTO THE PERIOD WITH THE
06Z/12Z GFS EJECTING THE UPPER LOW AND BRINGING A RETURN OF ZONAL
FLOW MUCH FASTER THAN THE SLOWER AND DEEPER 00Z ECMWF. THE CMC IS
BETWEEN THE TWO AND SEEMS TO BE AT LEAST A GOOD COMPROMISE IN THE
UPPER LEVELS THROUGH THIS PERIOD.
FOR NOW...WILL EMPLOY A BLEND OF THE MODELS...SIMILARLY TO WHAT HPC
HAS CONSTRUCTED THROUGH THE PERIOD...KEEPING AN UNSETTLED PATTERN
THROUGH SATURDAY BEFORE SHOWING A DRY OUT FOR SUNDAY AND MONDAY.
CONTINUED FORECAST OF TEMPERATURES SLIGHTLY COOLER THAN NORMAL THROUGH
THE PERIOD.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
EXPECT REMAINING MVFR COLD POOL STRATOCUMULUS CEILINGS AND
POTENTIALLY BRIEF MVFR SHOWERS TO DISSIPATE BY 08Z-11Z...PERHAPS
SOONER FOR KPIT AND WEST.
SURFACE WINDS WILL CONTINUE TO BE MAINLY WEST TO NORTHWEST BY SLOW
TO LESS THAN 10 KTS BEFORE 08Z.
EASTWARD BUILDING HIGH PRESSURE WILL PROMOTE VFR TUESDAY.
.OUTLOOK.../TUESDAY THROUGH SATURDAY/...
HIGH PRESSURE WILL CONTINUE VFR CONDITIONS INTO WEDNESDAY. THE
NEXT CHANCE FOR RESTRICTIONS WILL BE WITH THE FRONTAL PASSAGE
EXPECTED THURSDAY. AN UNSETTLED PATTERN BEHIND THE FRONT COULD
KEEP CHANCES FOR RESTRICTIONS THROUGH THE FIRST HALF OF THE
WEEKEND.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
712 PM EDT MON OCT 15 2012
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 414 PM EDT MON OCT 15 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH EAST
OF LAKE HURON LEAVING MAINLY ZONAL FLOW TO THE WEST FROM THE PAC NW TO
THE UPPER MS VALLEY. AN UPSTREAM SHORTWAVE TROUGH WAS MOVING FROM
THE NRN ROCKIES INTO THE NRN PLAINS. AT THE SFC...A RIDGE WAS
BUILDING ACROSS WRN LAKE SUPERIOR AND W UPPER MI. SRLY WINDS WERE
INCREASING OVER MN AHEAD OF A TROUGH FROM SRN MANITOBA INTO THE
CNTRL DAKOTAS. VIS LOOP SHOWED CLEARING SKIES OVER THE W HALF OF
UPPER MI. HOWEVER...HIGH CLOUDS SUPPORTED BY WAA AHEAD OF THE TROUGH
WERE QUICKLY STREAMING FROM MN INTO WRN WI. SOME LIGHT RAIN HAD ALSO
DEVELOPED FROM NEAR WINNIPEG INTO NW MN WITH WAA/ISENTROPIC LIFT
AHEAD OF THE TROUGH.
THE MODELS WERE IN GOOD AGREEMENT WITH THE MID LEVEL TROUGH DIGGING
FROM THE NRN PLAINS INTO THE UPPER MS VALLEY TONIGHT INTO TUE.
EXPECT THE AREA OF RAIN TO THE WEST TO EXPAND LATE TONIGHT AND
SPREAD INTO THE WRN CWA AS 925-850 MB MOISTURE TRANSPORT AND
295-300K ISENTROPIC LIFT INCREASE. AS THE 850-700 MB WARM FRONT
MOVES THROUGH THE AREA TUE...PCPN WILL SPREAD ACROSS THE CWA.
ALTHOUGH LIKELY-CATEGORICAL POPS WERE WARRANTED...THE HEAVIER PCPN
(INTO THE 0.25 TO 0.50 RANGE) IS EXPECTED MAINLY ACROSS THE NORTH
AND EAST FROM THE KEWEENAW INTO THE ERN CWA WHERE THE STRONGEST LIFT
AHEAD OF THE 850 MB WARM FRONT IS PROGGED....PER NAM/REGIONAL-GEM.
MODELS TIMING HAS ALSO BEEN CONSISTENT WITH THE PCPN ENDING OVER THE
WEST BY EARLY AFTERNOON AND OVER THE EAST LATE.
TEMPS WILL DROP INTO THE LOW TO MID 30S THIS EVENING BEFORE THE
CLOUDS THICKEN AND SRLY WINDS INCREASE RESULTING IN SLOWLY CLIMBING
TEMPS OVERNIGHT. AS THE PCPN ENDS TUE AFTERNOON...WAA WILL ALSO DRAW
ENOUGH WARM AIR INTO THE REGION TO PUSH MAX READINGS INTO UPPER 50S
WEST WHILE TEMPS LINGER AROUND 50 OVER THE EAST.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 414 PM EDT MON OCT 15 2012
MID WEEK WILL REMAIN UNSETTLED AS A DEEP UPPER TROUGH OVER THE
CANADIAN PRAIRIE PROVINCES CLOSES OFF OVER THE UPPER MIDWEST/GREAT
LAKES. THIS WILL ALLOW FOR PRECIPITATION CHANCES THROUGH THURSDAY
WITH AT OR SLIGHTLY BELOW NORMAL TEMPERATURES.
FOR THE DETAILS...EXPECT THE WARM ADVECTION/ISENTROPIC LIFT PCPN
ASSOCIATED WITH THE 850MB WARM FRONT TO MOVE EAST OF THE FORECAST
AREA TUESDAY NIGHT...LEADING TO THE AREA BEING IN THE WARM SECTOR
AHEAD OF THE DEEP SFC LOW AND OCCLUDED FRONT EXTENDING FROM LAKE
WINNIPEG INTO THE PLAINS. WILL MAINTAIN LOW CHANCE POPS IN THE
EVENING EAST OF MARQUETTE DUE TO CONTINUED WEAK ISENTROPIC LIFT AND
MID LVL Q-VECT CONVERGENCE. LOW CLOUDS/FOG WILL REMAIN A CONCERN
OVERNIGHT DUE TO CLEARING SKIES AND LEFTOVER LOW LEVEL MOISTURE FROM
AFTN/EVENING RAINFALL AND AS SUCH HAVE MAINTAINED FOG CHANCES.
THE OCCLUDED FRONT WILL MOVE EAST ON WEDNESDAY AS THE UPPER SYSTEM
CLOSES OFF. EXPECT A BAND OF SHOWERS TO MOVE INTO THE WESTERN U.P.
WEDNESDAY AFTERNOON ASSOCIATED WITH PRECIPITABLE WATER VALUES IN
EXCESS OF 1 INCH AND MID LVL Q-VECTOR CONVERGENCE. DUE TO THE LOW
CLOSING OFF...THE BAND OF SHOWERS WILL ONLY SLOWLY MOVE EAST WED
AFTN/NIGHT. IN FACT...THERE WILL LIKELY BE A PROLONGED PERIOD OF
STEADY RAIN WED EVENING ACROSS UPPER MICHIGAN DUE TO THE ROTATION
AND TIGHTENING OF THE 850MB ISOTHERMS CONTRIBUTING TO INCREASED
FN/FS VECTOR CONVERGENCE IN THE TROWAL REGION. WILL THEREFORE
MAINTAIN LIKELY POPS ACROSS THE ENTIRE U.P. WED NIGHT.
TRICKY AND UNCERTAIN FORECAST FOR THURSDAY. THE ECMWF SUGGESTS THAT
MOST OF THE U.P. WILL BE DRY WITH THE COMMA HEAD MOISTURE/PCPN BACK
INTO MN AND NW WISCONSIN DUE TO THE UPPER LOW BEING FURTHER WEST
THAN THE GFS WHICH HAS THE UPPER LOW OVERHEAD. AM THINKING THAT THE
BEST CHANCES FOR PCPN WILL BE ACROSS THE WEST AND HAVE OPTED TO
MAINTAIN HIGH CHANCE POPS FOR THAT AREA. DUE TO SIGNIFICANT
UNCERTAINTY...WILL STILL NEED TO MAINTAIN CHANCE POPS TO THE EAST.
CONFIDENCE IN THE EXTENDED FORECAST FOR FRIDAY-MONDAY STILL QUITE
LOW WITH DIFFERENCES BETWEEN THE ECWMF...GFS AND CANADIAN IN HOW
FAST THE GREAT LAKES CLOSED LOW EJECTS TO THE NORTHEAST. TEND TO
BELIEVE THE SLOWER ECMWF SOLUTION WHICH WOULD KEEP A DRIER FORECAST
FOR THE UPPER LAKES FOR THE WEEKEND DUE TO UPPER RIDGING HANGING ON
ACROSS THE UPPER MIDWEST. THE BELOW CONFIDENCE FORECAST NOT ONLY
APPLIES TO PRECIPITATION CHANCES...BUT ALSO TO TEMPERATURES AS THE
ECMWF WOULD BE WARMER COMPARED TO THE CLOUDY/COOL GFS.
WITH ALL OF THIS SAID...WILL TREND TOWARD THE 00Z AND 12Z ECMWF AND
LOWER POPS TO SLIGHT CHANCE OR LOW CHANCE POPS EACH DAY IN THE
EXTENDED. IN FACT IF THE 00Z ECMWF VERIFIES IT WILL END UP BEING A
DECENT WEEKEND. ON THE OTHER HAND...IF THE GFS VERIFIES IT COULD BE
MUCH WETTER.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 712 PM EDT MON OCT 15 2012
EXPECT VFR CONDITIONS TO CONTINUE OVERNIGHT AT ALL SITES AS A RIDGE
OF HIGH PRESSURE WITH DRIER AIR MOVES INTO THE REGION. ANOTHER
TROUGH WILL MOVE TOWARD THE AREA LATE TONIGHT BRINGING THICKENING
CLOUDS AND THE POTENTIAL FOR SOME LIGHT RAIN LATE TONIGHT. EXPECT
RAIN WITH MVFR CIGS TO MOVE IN TUESDAY AT KCMX AND CONDITIONS TO
STAY VFR THROUGH THE PERIOD AT KSAW AND KIWD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 414 PM EDT MON OCT 15 2012
WINDS WILL CONTINUE TO DIMINISH THIS EVENING AS HIGH PRES BUILDS
INTO THE REGION. ANOTHER LOW PRESSURE TROUGH APPROACHING THE UPPER
GREAT LAKES LATE TONIGHT WILL RESULT IN SOUTH WINDS OF 15 TO 25 KT
WITH AREAS TO NEAR 30 KT OVER ERN LAKE SUPERIOR LATE TUE AFTERNOON
AND EVENING. A DEEPER LOW PRESSURE SYSTEM MOVING INTO THE UPPER GREAT LAKES
ON THURSDAY COULD CAUSE AN INCREASE IN ERLY WINDS TO 30 KT LATE WED
NIGHT INTO THURSDAY. OTHERWISE...WINDS IN THE VICINITY OF THE LOW
SHOULD GENERALLY REMAIN LESS THAN 20 KTS WEDNESDAY THROUGH FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...MRD
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
627 PM EDT SUN OCT 14 2012
.UPDATE...
ISSUED AT 625 PM EDT SUN OCT 14 2012
DID AN EARLY UPDATE THIS EVENING TO ACCOUNT FOR A MORE EXTENSIVE
PERIOD OF RAIN ACROSS THE EASTERN HALF OF THE FORECAST AREA. THE LOW
OVER NRN MICHIGAN WILL BE SLOW TO MOVE NORTHEAST TONIGHT AS THE
UPPER TROUGH BECOMES NEGATIVELY TILTED. THIS WILL ALLOW FOR
DEEPENING TO CONTINUE THIS EVENING WITH A TROWAL TYPE FEATURE
EVENTUALLY DEVELOPING AS THE LOW OCCLUDES OUT. THIS TROWAL WILL HELP
TO STRENGTHEN THE FRONTOGENETIC FORCING TO THE NORTHWEST OF THE LOW
AND ALLOW FOR PCPN TO PERSIST FOR MUCH OF THE OVERNIGHT ACROSS THE
EASTERN 1/3 OF UPPER MICHIGAN. THE LATEST RAP RUN CLEARLY SHOWS PCPN
HANGING ON FOR MUCH OF THE NIGHT AT ERY. MEANWHILE...NORTH CENTRAL
UPPER MICHIGAN IS SEEING THE TERRAIN LIGHT UP DUE TO THE DEEPER
MOISTURE AND SLIGHTLY MORE NORTHERLY PBL FLOW. WITH ALL OF THIS
SAID...HAVE OPTED TO RAISE POPS TO CATEGORICAL THIS EVENING ACROSS
N-CENTRAL UPPER MICHIGAN AND THEN GRADUALLY DIMINISH OVERNIGHT AS
DRIER AIR MOVES IN. WILL ALSO MAINTAIN CATEGORICAL POPS ALL NIGHT
ACROSS THE EAST. SOME PLACES ACROSS THE EASTERN HALF OF UPPER MI
WILL SEE OVER 2 INCHES OF RAIN BY MONDAY MORNING. MANY PLACES ARE
ALREADY WELL OVER 1 INCH TODAY.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 351 PM EDT SUN OCT 14 2012
CURRENT /18Z/ ANALYSIS SHOWS A STRONG UPPER SHORTWAVE TROUGH
STRETCHING FROM N MN TO N IL...WITH AN ELONGATED 998MB SFC LOW FROM
N IL TO NE LOWER MI. THE NE PORTION OF THE SFC LOW SHOULD BEGIN TO
DOMINATE AS THE DRY SLOT IS MOVING OVER REDUCING STATIC
STABILITY...AND SINCE THE UPPER SHORTWAVE FOCUS OVER THIS
AREA...FAVORING CYCLOGENESIS. THE 850MB LOW IS JUST SE OF
MENOMINEE...WITH A LARGE SHIELD OF MODERATE TO HEAVY RAINFALL ON THE
NW SIDE OF THIS FEATURE. THE NW EXTENT OF THE RAIN SHIELD EXTENDS
FROM NEAR ARX...TO RHI...TO CRYSTAL FALLS...TO MQT...TO E LAKE
SUPERIOR. AS NOTED BEFORE...HEAVY RAIN HAS BEEN REPORTED...MAINLY
CLOSER TO LAKE MICHIGAN WITH RAIN AMOUNTS UP TO AN INCH SO FAR OVER
SCENTRAL UPPER M. ADDITIONALLY...UPSLOPE FLOW AND AMPLE LOW LEVEL
MOISTURE IS BRINGING DRIZZLE/BR AND RAIN SHOWERS TO MUCH OF THE REST
OF THE CWA. ON THE NW SIDE OF THE SYSTEM IS A SFC RIDGE THAT WILL
MOVE INTO THE CWA TOMORROW.
THE DEFORMATION/FGEN FORCING AXIS AND ASSOCIATED PRECIP IS NOT
EXPECTED TO MOVE MUCH MORE NW THAN WHAT IT IS NOW SINCE IT IS
PIVOTING AROUND THE 850MB LOW...AND IS ALREADY STARTING TO PUSH
SLOWLY E ALONG THE WI BORDER. AS THE UPPER SHORTWAVE MOVES TO THE
ERN CWA BY 06Z MON...THE SFC LOW WILL MOVE TO LAKE HURON AND THE
BAND OF SYNOPTIC PRECIP WILL MOVE TO THE FAR ERN CWA OR JUST E OF
THE CWA. AS MODERATELY COLD 850MB TEMPS OF -2C TO -4C MOVES OVER
LAKE SUPERIOR BY 06Z MON...EXPECT SOME ISOLATED TO SCATTERED LAKE
EFFECT RAIN SHOWERS AND DRIZZLE FROM THE NLY UPSLOPE FLOW. BY TIME
THE COLDER AIR MOVES INTO THE NEAR SFC LAYER...LOW LOW LEVEL
MOISTURE WILL BE PRESENT...SO NOW SNOW IS EXPECTED. THE LAKE EFFECT
PRECIP WILL TAPER OFF FROM W TO E AS DRIER LOW LEVEL AIR MOVES IN
WITH THE SFC RIDGE. THE RIDGE WILL MOVE TO NEAR IWD BY 18Z
MON...THEN TO THE CENTER OF THE CWA BY 00Z TUE...BRINGING A RETURN
OF WARMER 850MB TEMPS UP TO 4C.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 449 PM EDT SUN OCT 14 2012
MONDAY NIGHT INTO TUE...MDLS WERE IN REASONABLE AGREEMENT WITH THE
MID LEVEL AND SFC RIDGE SLIDING QUICKLY TO THE EAST AND A MAINLY
ZONAL PATTERN ACROSS THE NRN CONUS. WAA/ISENTROPIC LIFT AHEAD OF THE
NEXT SHORTWAVE TROUGH WILL BRING INCREASING CLOUDS ACROSS THE AREA
MON NIGHT WITH RAIN CHANCES SPREADING INTO WRN UPPER MI. MODERATE TO
STRONG 300K ASCENT WITH MOISTURE INFLOW BRINGING PWAT VALUES TO
AROUND AN INCH SUPPORT LIKELY POPS OVER MOST OF THE CWA...ESPECIALLY
FOR THE CNTRL AND EAST EVEN IF QPF VALUES ARE ONLY A TENTH OF TWO.
EXPECT THAT THE PCPN WILL TAPER OFF IN THE WEST HALF BY AFTERNOON
AND THE EAST LATE.
TUE NIGHT AND WED...MDLS SUGGEST THAT AS STRONG UPPER LEVEL JET
ENERGY INTO THE PAC NW DIGS TO THE SE A BROAD MID/UPPER LEVEL TROUGH
WILL DEVELOP OVER THE PLAINS. WAA WILL INCREASE AHEAD OF A SFC
TROUGH EXTENDED FROM SRN MANITOBA INTO WRN MN BY 12Z/WED. THE ECMWF
WAS PREFERRED WITH A SLIGHTLY LATER ARRIVAL OF ANY PCPN INTO UPPER
MI AS THE STRONGER FORCING WITH THE JET AND MID LEVEL LOW REMAIN TO
THE SW OF UPPER MI. EVEN THOUGH 850 MB TEMPS CLIMB TO AROUND
10C...INCREASING CLOUDS SHOULD LIMIT MAX READINGS TO AROUND 60.
THU-SUN...MDLS DIFFERENCES BECOME MORE SIGNFICANT AS THE GFS/GEFS
BECOME MORE PROGRESSIVE BY NEXT WEEKEND COMPARED TO THE 00Z ECMWF
AND ASSOCIATED ENSEMBLES. EVEN THOUGH THE 12Z ECMWF HAS TRENDED MORE
TOWARD THE GFS...CONFIDENCE IN THE OVERALL PATTERN AND DETAILS IS
LOW. EXPECT THE BEST CHANCE OF PCPN FROM WED NIGHT INTO THU AS THE
SFC TROUGH AND MOISTURE AXIS LIFTS INTO THE REGION. BEYOND THU...THE
POSITION OF THE DRY SLOT OR ADDITIONAL WEAK IMPULSES AROUND THE MID
LEVEL LOW IS VERY UNCERTAIN. ABOVE NORMAL TEMPS WILL COOL BACK AGAIN
AOB SEASONAL AVERAGES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 131 PM EDT SUN OCT 14 2012
AMPLE LOW LEVEL MOISTURE FLOWING AROUND A LOW PRESSURE SYSTEM
SOUTHEAST OF THE AREA WILL KEEP LOW CIGS...WITH DZ AND -RA INTO
TONIGHT. -RA AND LOW CIGS WILL STICK AROUND THE LONGEST AT SAW INTO
LATE TONIGHT. AS THE SYSTEM MOVES EAST AND A RIDGE OF HIGH PRESSURE
MOVES IN FROM THE WEST LATE TONIGHT INTO MON MORNING...CONDITIONS
WILL BEGIN TO IMPROVE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 301 PM EDT SUN OCT 14 2012
EXPECT N TO NE WINDS TO INCREASE INTO TONIGHT AS A LOW PRESSURE
SYSTEM OVER NORTHERN LAKE MICHIGAN LIFTS NE TO LAKE HURON BY LATE
TONIGHT. LATE THIS AFTERNOON AND EARLY EVENING...WINDS SHOULD BE IN
THE 20-30KT RANGE OVER PRIMARILY THE CENTRAL AND ERN PORTIONS OF
LAKE SUPERIOR. WINDS WILL BE LIGHTER OVER THE FAR WRN LAKE. EXPECT
NORTHERLY GALES TO DEVELOP OVER ROUGHLY THE EASTERN HALF OF LAKE
SUPERIOR LATE THIS EVENING AND THEN CONTINUE INTO MONDAY MORNING AS
THE LOW RAPIDLY DEEPENS AND MOVES EAST OF THE AREA AND HIGH PRESSURE
PUSHES IN FROM THE WEST. WINDS SETTLE DOWN MONDAY AFTERNOON AND
MONDAY NIGHT WITH ARRIVAL OF HIGH PRESSURE. ANOTHER LOW PRESSURE
SYSTEM WILL MOVE INTO THE UPPER GREAT LAKES ON WEDNESDAY INTO
WEDNESDAY NIGHT. SOUTH WINDS AHEAD OF THIS LOW COULD BRIEFLY REACH
GALES TO 35 KTS OVER ERN LAKE SUPERIOR TUE AFTERNOON.
OTHERWISE...WINDS IN THE VICINITY OF THE LOW SHOULD REMAIN LESS THAN
20 KTS WEDNESDAY THROUGH FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 10 AM EDT MONDAY FOR LSZ249>251-266-267.
LAKE MICHIGAN...
GALE WARNING UNTIL 11 AM EDT MONDAY FOR LMZ221-250.
&&
$$
UPDATE...MRD
SHORT TERM...TITUS
LONG TERM...JLB
AVIATION...TITUS
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
452 PM EDT SUN OCT 14 2012
.SYNOPSIS...
ISSUED AT 400 PM EDT SUN OCT 14 2012
STRONG LOW PRESSURE WILL MOVE ACROSS NORTHERN LOWER MICHIGAN AND
LAKE HURON TONIGHT. THIS SYSTEM WILL CONTINUE TO PRODUCE SCATTERED
RAIN SHOWERS AND ISOLATED THUNDERSTORMS... SOME OF WHICH MAY PRODUCE
STRONG WIND GUSTS TONIGHT.
COOL AND BREEZY CONDITIONS WITH SCATTERED SHOWERS CAN BE EXPECTED ON
MONDAY ON THE BACK SIDE OF THE DEPARTING LOW PRESSURE SYSTEM. MILDER
WEATHER WILL RETURN FOR TUESDAY AND WEDNESDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 400 PM EDT SUN OCT 14 2012
HIGH SHEAR/LOW CAPE ENVIRONMENT THIS AFTERNOON AND EARLY EVENING AS
STRONG SHORTWAVE NEAR CHICAGO PIVOTS NORTHEAST. WARMS SECTOR OF
INTENSIFYING SFC CYCLONE HAS PUSHED FARTHER NORTH THAN EARLIER
EXPECTED AS MAIN SFC LOW DEEPENS OVER NRN LWR MI. SFC CAPES HAVE
RISEN ABV 500 J/KG WHICH DOESN/T SOUND LIKE MUCH BUT 0-6KM SHEAR IS
AROUND 60 KTS. SINCE WINDS AT 3-5K FT ARE AROUND 50 KTS... THERE IS
CONCERN THAT SOME OF THE DEVELOPING CONVECTION WILL PRODUCE DAMAGING
WIND GUSTS OR BRIEFLY ROTATE. OF PARTICULAR CONCERN IS THE SOMEWHAT
MORE ORGANIZED CONVECTION CURRENTLY AROUND CHICAGO WHICH IS HEADING
THIS WAY. THE CURRENT LIMITED SVR WX THREAT SHOULD END SHORTLY AFTER
SUNSET AS THE THE COLD FRONT SWEEPS THROUGH.
PERIOD OF STRONG/GUSTY SYNOPTIC WINDS IS EXPECTED LATER THIS EVENING
AS THE SFC LOW DEEPENS TO 988 OVER NRN LK HURON (LATEST RAP13 PROG).
WIND SPEEDS/GUSTS FROM THE WEST NORTHWEST ARE CURRENTLY EXPECTED TO
BE JUST BELOW WIND ADVISORY CRITERIA... BUT THIS WILL NEED TO BE
MONITORED OVER THE NEXT FEW HOURS.
COOL AND BREEZY CONDITIONS EXPECTED ON MONDAY AS THE LOW PULLS AWAY
WITH SOME LINGERING WRAPAROUND/COLD ADVECTION RAIN SHOWERS...
ESPECIALLY EARLY. THEN A COLD NIGHT WITH DECREASING CLOUDS/WIND ON
MONDAY NIGHT AS THE SFC RIDGE MOVES OVHD. ALREADY WARM ADVECTING
AGAIN ON TUESDAY IN PROGRESSIVE PATTERN. RETURNING SW FLOW MAY
SQUEEZE OUT A FEW LIGHT SHOWERS.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 400 PM EDT SUN OCT 14 2012
THE LONG TERM PORTION OF THE FCST WILL BE DOMINATED BY ONE MAIN
SYSTEM THAT LOOKS TO HOLD IN ACROSS THE AREA THROUGH MOST OF...IF
NOT ALL OF THE LONG TERM PERIOD THROUGH NEXT SUNDAY.
THE STRONG UPPER JET CURRENTLY JUST SOUTH OF THE GULF OF ALASKA WILL
BE THE MAIN DRIVING FORCE BEHIND THE SYSTEM THAT WILL AFFECT THE
AREA MOST OF THE LONG TERM. THIS JET IS EXPECTED TO HELP DIG A
STRONG SYSTEM ACROSS THE PLAINS OR UPPER MS RIVER VALLEY. MODELS ARE
EVENTUALLY CLOSING THE SYSTEM OFF...HOWEVER THEY DIFFER ON THE
EVENTUAL EVOLUTION.
EITHER WAY...IT LOOKS LIKE THE AREA IS IN FOR AN UNSETTLED PERIOD OF
WEATHER. THE SYSTEM SHOULD MOVE IN LATE WED/WED NIGHT WITH THE FRONT
APPROACHING THE AREA. THIS SHOULD BRING THE BEST CHC OF MORE
WIDESPREAD RAIN TO THE AREA. TEMPERATURES WILL REMAIN COOL WITH
SOMEWHAT LIMITED DIURNAL TEMPERATURES SWINGS DUE TO THE CLOUD COVER.
ONCE THE FRONT MOVES THROUGH ON THU...THE PCPN SHOULD BECOME MORE
SCATTERED AND UNCERTAIN DEPENDING ON THE MOVEMENT OF THE UPPER LOW
AND ANY DISTURBANCES THAT WILL BE ROTATING AROUND IT. THIS WILL
REQUIRE KEEPING A CHC OF RAIN IN THE FORECAST THROUGH AT LEAST THE
END OF THE WORK WEEK. WE ARE LEANING TOWARD THE EURO MODEL AND
KEEPING THE CHC OF RAIN IN THROUGH NEXT WEEKEND. THE GFS SEEMS TO
LIFT THE SYSTEM OUT A BIT TOO QUICK CONSIDERING HOW BIG AND CLOSED
OFF THIS SYSTEM IS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 448 PM EDT SUN OCT 14 2012
THIS IS A QUICK UPDATE BECUASE I UPDATED ALL OF THE TAFS TO TIME
THE LINE OF STORMS ACROSS THE CWA. I USED THE COMBINATION OF THE
TIME TOOL (ON AWIPS) AND THE HRRR RUC TO TIME THE STORMS THROUGH.
OVER THE PAST HOUR THE TIMING TOOL HAS TRACKED WELL AND WHERE THE
LINE IS NOW IS IN GOOD AGREEMENT WITH THE HRRR TIMING OF THE LINE.
AFTER THE LINE MOVES THROUGH I EXPECT VFR CIGS/VSBY BUT WINDY
CONDITIONS. THE WRAP AROUND LOW CLOUDS AND SHOWERS WILL IMPACT GRR
AND MKG MORE THAN AZO...BTL...JXN AND LAN BUT I TRIED TO TIME THAT
EAST TOO.
&&
.MARINE...
ISSUED AT 400 PM EDT SUN OCT 14 2012
SOUTH WINDS HAVE BRIEFLY GUSTED TO GALE FORCE RECENTLY... BUT MORE
PERSISTENT GALES FROM THE NW ARE LIKELY LATER THIS EVENING AND
OVERNIGHT ONCE THE SFC LOW PASSES BY. WINDS WILL DIMINISH LATE
MONDAY.
&&
.HYDROLOGY...
ISSUED AT 400 PM EDT SUN OCT 14 2012
MOST STORM TOTAL RAIN AMOUNTS HAVE BEEN ONE TO TWO INCHES...
ALTHOUGH SOME REPORTS HAVE BEEN HIGHER ESPECIALLY IN THE NW CWFA.
THERE HAVE BEEN NO REPORTS OF FLOODING DUE TO THE PROLONGED NATURE
OF THE EVENT...AND RIVERS WHICH WERE VERY LOW ARE STILL EXPECTED TO
REMAIN BELOW BANKFULL. ADDITIONAL RAIN AMOUNTS SHOULD BE MOSTLY A
HALF INCH OR LESS TONIGHT AND MONDAY.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LMZ844>849.
GALE WARNING FROM 8 PM THIS EVENING TO 5 AM EDT MONDAY FOR
LMZ844>849.
&&
$$
SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...NJJ
AVIATION...WDM
HYDROLOGY...MEADE
MARINE...MEADE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
132 PM EDT SUN OCT 14 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 610 AM EDT SUN OCT 14 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS CONTINUE TO SHOW A ZONAL FLOW
ACROSS SRN CANADA AND THE FAR NRN CONUS WITH A WELL-DEFINED
SHORTWAVE OVER ERN KS AND WRN MO POISED TO LIFT NE TOWARD THE
CENTRAL GREAT LAKES THIS AFTERNOON. DEFORMATION/FRONTOGENESIS RAIN
BAND IN DEVELOPING BAROCLINIC LEAF/COMMA HEAD OF SHORTWAVE
STRETCHING FROM ERN NEBRASKA AND NRN IA INTO CENTRAL WI LINES UP
NICELY WITH 700 MB FGEN FORCING AS DEPICTED BY 00Z GFS. SO FAR EARLY
THIS MORNING...RADAR SHOW ONLY SPURIOUS SHRA ACTIVITY MOVING ACROSS
SCNTRL AND SE UPR MI IN AREA OF WEAK Q-VECT CONV AND FGEN FORCING.
THERE HAS ALSO BEEN SOME UPSLOPE DZ AT KMQT EARLY THIS MORNING IN
NRLY FLOW.
PCPN TRENDS/COVERAGE WILL BE THE MAIN FCST ISSUES IN THE SHORT TERM.
ZONAL FLOW ACROSS SRN CANADA/FAR NRN CONUS IS EXPECTED TO BUCKLE
TODAY AS HEIGHT RISES OVER WRN NAMERICA FORCE DOWNSTREAM HEIGHT
FALLS INTO MISSISSIPPI VALLEY REGION. THIS WILL HELP EJECT THE
CENTRAL PLAINS SHORTWAVE NE INTO THE GREAT LAKES THIS AFTERNOON.
EXACTLY HOW FAR N THE SHORTWAVE LIFTS ACROSS LOWER MI WILL BE
IMPORTANT TO THE PCPN COVERAGE TODAY. EVEN NOW...SO CLOSE TO THE
ONSET OF THE EVENT...THE MODELS ARE STILL EXHIBITING SIGNIFICANT RUN
TO RUN DIFFERENCES. THE MAJORITY OF THE 00Z RUNS WERE SHOWING THE
MAIN PCPN BAND STAYING MAINLY SOUTH OF THE FCST AREA...BRUSHING THE
FAR SCNTRL AND ERN FCST AREA WITH AROUND A HALF INCH OF RAINFALL
WITH A FAIRLY SHARP CUT-OFF OF PCPN HEADING NORTH AND WEST. NOW THE
06Z NAM AND GFS HAVE TRENDED FARTHER NORTH AND WEST WITH PCPN
SHIELD...STILL DROPPING THE HEAVIEST RAIN OVER THE SCNTRL AND EAST
BUT ALSO BRINGING ANYWHERE FROM 0.25-0.50 INCH INTO DICKINSON AND SE
HALF OF MQT COUNTY.
LATEST RADAR TRENDS AND MODEL FGEN FIELDS SUGGEST A SLIGHT NORTHWARD
TREND IN MAIN PCPN BAND IS POSSIBLE AS SHORTWAVE LIFTS TOWARD REGION
TODAY AND THIS WILL BE SOMETHING TO WATCH AS THE MORNING PROGRESSES.
SHORT TERM FCST UPDATES MAY NEED TO EXPAND CATEGORICAL POPS OVER FAR
SCNTRL AND ERN FCST AREA FARTHER NW TO ACCOUNT FOR THESE PCPN
TRENDS.
TONIGHT...AS SHORTWAVE AND ASSOC SFC LOW LIFT EAST OF THE REGION
LATER TONIGHT...EXPECT PCPN TO TAPER OFF OVER CENTRAL PORTIONS OF
THE CWA THIS EVENING AND OVER ERN PORTIONS OVERNIGHT. WITH MARGINAL
COLD ADVECTION BEHIND THE SYSTEM TONIGHT...AND BUFR SNDGS AND WET
BULB ZERO HGTS NOT REALLY SUPPORTING MUCH IN THE WAY OF PCPN
MIXING/CHANGING TO SNOW LATE TONIGHT...HAVE DECIDED TO PULL MENTION
OF SNOW LATE TONIGHT FOR NCNTRL ZONES. STRONG DEEP CYCLONIC NRLY
FLOW WILL LIKELY SUPPORT SOME LAKE EFFECT UPSLOPE RAIN/DZ THROUGH
MUCH OF NIGHT OVER NCNTRL PORTIONS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 610 AM EDT SUN OCT 14 2012
UPPER LEVEL PATTERN TO BEGIN THE LONG TERM ON MONDAY HAS A TROUGH
FROM HUDSON BAY INTO THE OHIO VALLEY WITH ASSOCIATED SFC LOW LIFTING
INTO SOUTHERN QUEBEC. KEPT MENTION OF LIGHT LK EFFECT PRECIP FIRST
THING ON MONDAY MORNING OVER NORTH CENTRAL WITH H85 TEMPS DOWN TO
-3C LEADING TO MARGINAL OVER-WATER INSTABILITY WITH DELTA T/S OVER
15C. SOUNDINGS FOR MQT FROM GFS/NAM INDICATE WBZERO HEIGHTS STAYING
AOA 1000FT AGL SO KEPT PTYPE AS ONLY RAIN. EVEN WITH CYCLONIC
NORTHERLY FLOW IN WAKE OF SFC LOW MOVING INTO QUEBEC...SOUNDINGS
SHOW ONLY A SHALLOW MOIST LAYER AFTER 12Z MONDAY WITH TEMPS IN THE
MOIST LAYER NOT ANY COLDER THAN -5C. SO...MAY JUST END UP WITH
FINE DRIZZLE OR MAYBE JUST A FEW SPRINKLES SINCE SUB CLOUD LAYER IS
INCREASINLY MIXED WITH INVERTED-V LOOK.
SFC RIDGE FOLLOWING IN WAKE OF THE SFC LOW SHOULD BE IN PROCESS OF
WORKING ACROSS UPPER GREAT LAKES BY AFTN WHICH WILL CONK OUT ANY
LINGERING RAIN SHOWERS/DRIZZLE/SPRINKLES. CLOUDS USUALLY TOUGHER TO
GO AND WOULD EXPECT SCT-BKN STRATOCU TO HANG AROUND TIL LATER AFTN
AS H85 RIDGE BEGINS TO MOVE INTO THE AREA.
UPPER FLOW BECOMES MORE WESTERLY INTO TUESDAY ALLOWING WEAK SFC
TROUGH/WARM FRONT TO SKIRT ACROSS NORTHERN ONTARIO AND UPPER GREAT
LAKES. ALTHOUGH SFC REFLECTION IS WEAK...ACTUALLY IS STRONG WARM AIR
ADVECTION ALOFT WITH THE AHEAD AND ALONG SHORTWAVE PASSING OVER THE
REGION. ISENTROPIC ASCENT ON THE 300K SFC /H8-H7/ IMPACTS MOST OF
CWA...BUT STRONGEST H85 TEMP ADVECTION IS MORE OVER THE NORTH CWA.
OVERALL A PERIOD OF MOISTURE/STRONG UVM IN THE H7-H5 LAYER /TEMPS
BLO -10C/ ARE FORECAST WHICH SHOULD IN TURN LEAD TO GREATER CHANCE
OF SEEING SOME RAIN MAKE IT TO SFC DESPITE DRY SUB H85 LAYERS MODELS
SHOW. LOOKS LIKE HIGHER POP/LOW QPF SETUP. INCREASED POPS TO LIKELY
OVER NORTH AND ALSO EAST. HIGH CHANCES SHOULD COVER IT FOR AREAS
FARTHER AWAY FROM MID LEVEL LIFT. MID LEVEL MOISTURE/UVM EXITS TO
THE FAR EAST CWA BY LATE DAY...SO HAVE TRIMMED BACK POPS IN THE WEST
AFTER 18Z AND FOR ALL AREAS ON INTO TUESDAY NIGHT. DESPITE
CLOUDS/SHOWERS...WARMING TEMPS ALOFT AND A SOUTH WIND SHOULD ALLOW
FOR TEMPS TO PUSH ABOVE NORMAL...ESPECIALLY DURING AFTN AS PRECIP
TAPERS OFF. COULD SEE SOME SPOTS ON TUESDAY TOUCH 60 DEGREES IF
ENOUGH THINNING IN OVERCAST OCCURS. BEST SHOT FOR WARMER TEMPS IN
THE WEST AND SOUTHWEST CWA.
ATTENTION TUESDAY NIGHT INTO WEDNESDAY WILL BE ON SHORTWAVE TROUGH
AND STRONG UPPER LEVEL JET DIGGING INTO PACIFIC NORTHWEST.
ASSOCIATED SFC LOW /PRETTY DEEP AT SUB 985MB/ FORMS OVER SOUTHERN
ALBERTA LATER TUESDAY WITH COMPLEX OF LOWS THEN DEVELOPING FROM
SASKATCHEWAN INTO MINNESOTA AND WESTERN WISCONSIN BY LATE DAY ON
WEDNESDAY. SLIGHT POTENTIAL FOR COUPLE BATCHES OF MID LEVEL MOISTURE
LIFTING ACROSS TUESDAY NIGHT TO YIELD SPRINKLES OR A SHOWER ON
TUESDAY NIGHT. FOR MOST PART THOUGH THE NIGHT SHOULD END UP DRY
AND FAIRLY MILD FOR MID-LATE OCTOBER WITH LOWS IN THE MID-UPPER 40S.
NOW SEEMS LIKE WEDNESDAY WILL BE FOR MOST PART FAIRLY VOID OF SIG
PRECIP OVER THE CWA. UPPER TROUGH AND IDEAL JET SUPPORT FOR PRECIP
REMAIN WELL TO WEST OVER MIDDLE MISSISSIPPI RIVER VALLEY. ALSO
SOME INDICATION FROM LATEST ECMWF THAT SHARPER SHORTWAVE EMBEDDED IN
SOUTHERN PORTION OF UPR TROUGH WILL FOCUS SFC LOW FARTHER SOUTH OVER
SOUTHERN IOWA WHICH KEEPS H85 JET AND HIGHER H85 DWPNT LOCKED UP
MORE TO SOUTHWEST OF CWA. KEPT CHANCE POPS OVER WEST AND SOUTHWEST
CWA...BUT DID TRIM TO ONLY SLIGHT CHANCES OVER THE EASTERN CWA.
SIMILAR TO TUESDAY...GIVEN WARM AIR ALOFT /H85 TEMPS PUSHING +10C
OVER SOUTH CWA/ AND SOUTHERLY WINDS...MAX TEMPS COULD PUSH PAST 60
DEGREES AGAIN. TRENDS IN CLOUD COVER WILL HAVE BIG IMPACT ON TEMPS
THOUGH AS IF PARTIAL CLEARING COULD OCCUR OVER CWA...TEMPS MAKING
RUN WELL INTO THE 60S /EVEN AN ISOLD 70 DEGREE READING/ WOULD BE
FEASIBLE.
BEYOND WEDNESDAY MODELS DIVERGE WITH HANDLING OF TROUGH AND SFC
LOW TO CLOSE THE WEEK. GFS BECOMES MORE PROGRESSIVE WITH LOW PUSHING
TOWARD LK MICHIGAN BY THURSDAY AFTERNOON WHILE ECMWF AND GEM-NHEM
SHOW MORE OF A SLOWER UPPER TROUGH PROGRESSION AND KEEP PRIMARY SFC
LOW LUMBERING MORE OVER SOUTHERN PORTION OF MINNESOTA THROUGH
THURSDAY. SFC LOW PLACEMENT PRETTY MUCH ALL OVER THE PLACE IN MORE
RECENT MODEL RUNS. SINCE THE SYSTEM IS VERY WRAPPED UP ON ALL
MODELS...POTENTIAL IS THERE FOR SIGNIFICANT DRY SLOTTING SOMETIME
THURSDAY INTO FRIDAY ALONG WITH MINOR SHORTWAVES ROTATING AROUND
MAIN UPPER LOW. LEANED HEAVILY ON CONSENSUS FOR POPS/SKY/WINDS FOR
THURSDAY AND BEYOND DUE TO LACK OF CONSISTENCY IN ANY OF THE MODELS
AND VARYING SOLUTIONS WITH HANDLING OF UPPER TROUGH/SFC LOW. COULD
EASILY SEE WINDS BEING MUCH STRONGER THAN IS SHOWN WITH THIS
FORECAST...ESPECIALLY THURSDAY AND FRIDAY...BUT AT THIS POINT
CANNOT PIN POINT WHERE THE STRONGER WINDS WILL OCCUR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 131 PM EDT SUN OCT 14 2012
AMPLE LOW LEVEL MOISTURE FLOWING AROUND A LOW PRESSURE SYSTEM
SOUTHEAST OF THE AREA WILL KEEP LOW CIGS...WITH DZ AND -RA INTO
TONIGHT. -RA AND LOW CIGS WILL STICK AROUND THE LONGEST AT SAW INTO
LATE TONIGHT. AS THE SYSTEM MOVES EAST AND A RIDGE OF HIGH PRESSURE
MOVES IN FROM THE WEST LATE TONIGHT INTO MON MORNING...CONDITIONS
WILL BEGIN TO IMPROVE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 610 AM EDT SUN OCT 14 2012
EXPECT N TO NE WINDS TO INCREASE TODAY AS LOW PRES OVER THE CENTRAL
PLAINS LIFTS NE INTO NRN LWR MICHIGAN THIS AFTERNOON. DURING THE
AFTN...WINDS SHOULD BE IN THE 20-30KT RANGE OVER THE CNTRL AND ERN
PORTIONS OF LAKE SUPERIOR. WINDS WILL BE LIGHTER OVER THE FAR W.
EXPECT NORTHERLY GALES TO DEVELOP OVER EASTERN LAKE SUPERIOR THIS
EVENING AND THEN CONTINUE INTO MONDAY MORNING AS THE LOW RAPIDLY
DEEPENS AND MOVES EAST OF THE AREA AND HIGH PRESSURE PUSHES IN FROM
THE WEST. WINDS SETTLE DOWN MONDAY AFTERNOON AND MONDAY NIGHT WITH
ARRIVAL OF HIGH PRESSURE. ANOTHER LOW PRESSURE WILL MOVE INTO THE
UPPER GREAT LAKES ON WEDNESDAY. SOUTH WINDS AHEAD OF THIS LOW COULD
BRIEFLY REACH GALES TO 35 KTS OVER ERN LAKE SUPERIOR TUE AFTERNOON.
OTHERWISE...WINDS IN THE VICINITY OF THE LOW SHOULD REMAIN LESS THAN
20 KTS WEDNESDAY INTO THURSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 7 PM THIS EVENING TO 10 AM EDT MONDAY FOR
LSZ266-267.
LAKE MICHIGAN...
GALE WARNING FROM 6 PM THIS EVENING TO 11 AM EDT MONDAY FOR
LMZ221-250.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...TITUS
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
747 AM EDT SUN OCT 14 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 610 AM EDT SUN OCT 14 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS CONTINUE TO SHOW A ZONAL FLOW
ACROSS SRN CANADA AND THE FAR NRN CONUS WITH A WELL-DEFINED
SHORTWAVE OVER ERN KS AND WRN MO POISED TO LIFT NE TOWARD THE
CENTRAL GREAT LAKES THIS AFTERNOON. DEFORMATION/FRONTOGENESIS RAIN
BAND IN DEVELOPING BAROCLINIC LEAF/COMMA HEAD OF SHORTWAVE
STRETCHING FROM ERN NEBRASKA AND NRN IA INTO CENTRAL WI LINES UP
NICELY WITH 700 MB FGEN FORCING AS DEPICTED BY 00Z GFS. SO FAR EARLY
THIS MORNING...RADAR SHOW ONLY SPURIOUS SHRA ACTIVITY MOVING ACROSS
SCNTRL AND SE UPR MI IN AREA OF WEAK Q-VECT CONV AND FGEN FORCING.
THERE HAS ALSO BEEN SOME UPSLOPE DZ AT KMQT EARLY THIS MORNING IN
NRLY FLOW.
PCPN TRENDS/COVERAGE WILL BE THE MAIN FCST ISSUES IN THE SHORT TERM.
ZONAL FLOW ACROSS SRN CANADA/FAR NRN CONUS IS EXPECTED TO BUCKLE
TODAY AS HEIGHT RISES OVER WRN NAMERICA FORCE DOWNSTREAM HEIGHT
FALLS INTO MISSISSIPPI VALLEY REGION. THIS WILL HELP EJECT THE
CENTRAL PLAINS SHORTWAVE NE INTO THE GREAT LAKES THIS AFTERNOON.
EXACTLY HOW FAR N THE SHORTWAVE LIFTS ACROSS LOWER MI WILL BE
IMPORTANT TO THE PCPN COVERAGE TODAY. EVEN NOW...SO CLOSE TO THE
ONSET OF THE EVENT...THE MODELS ARE STILL EXHIBITING SIGNIFICANT RUN
TO RUN DIFFERENCES. THE MAJORITY OF THE 00Z RUNS WERE SHOWING THE
MAIN PCPN BAND STAYING MAINLY SOUTH OF THE FCST AREA...BRUSHING THE
FAR SCNTRL AND ERN FCST AREA WITH AROUND A HALF INCH OF RAINFALL
WITH A FAIRLY SHARP CUT-OFF OF PCPN HEADING NORTH AND WEST. NOW THE
06Z NAM AND GFS HAVE TRENDED FARTHER NORTH AND WEST WITH PCPN
SHIELD...STILL DROPPING THE HEAVIEST RAIN OVER THE SCNTRL AND EAST
BUT ALSO BRINGING ANYWHERE FROM 0.25-0.50 INCH INTO DICKINSON AND SE
HALF OF MQT COUNTY.
LATEST RADAR TRENDS AND MODEL FGEN FIELDS SUGGEST A SLIGHT NORTHWARD
TREND IN MAIN PCPN BAND IS POSSIBLE AS SHORTWAVE LIFTS TOWARD REGION
TODAY AND THIS WILL BE SOMETHING TO WATCH AS THE MORNING PROGRESSES.
SHORT TERM FCST UPDATES MAY NEED TO EXPAND CATEGORICAL POPS OVER FAR
SCNTRL AND ERN FCST AREA FARTHER NW TO ACCOUNT FOR THESE PCPN
TRENDS.
TONIGHT...AS SHORTWAVE AND ASSOC SFC LOW LIFT EAST OF THE REGION
LATER TONIGHT...EXPECT PCPN TO TAPER OFF OVER CENTRAL PORTIONS OF
THE CWA THIS EVENING AND OVER ERN PORTIONS OVERNIGHT. WITH MARGINAL
COLD ADVECTION BEHIND THE SYSTEM TONIGHT...AND BUFR SNDGS AND WET
BULB ZERO HGTS NOT REALLY SUPPORTING MUCH IN THE WAY OF PCPN
MIXING/CHANGING TO SNOW LATE TONIGHT...HAVE DECIDED TO PULL MENTION
OF SNOW LATE TONIGHT FOR NCNTRL ZONES. STRONG DEEP CYCLONIC NRLY
FLOW WILL LIKELY SUPPORT SOME LAKE EFFECT UPSLOPE RAIN/DZ THROUGH
MUCH OF NIGHT OVER NCNTRL PORTIONS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 610 AM EDT SUN OCT 14 2012
UPPER LEVEL PATTERN TO BEGIN THE LONG TERM ON MONDAY HAS A TROUGH
FROM HUDSON BAY INTO THE OHIO VALLEY WITH ASSOCIATED SFC LOW LIFTING
INTO SOUTHERN QUEBEC. KEPT MENTION OF LIGHT LK EFFECT PRECIP FIRST
THING ON MONDAY MORNING OVER NORTH CENTRAL WITH H85 TEMPS DOWN TO
-3C LEADING TO MARGINAL OVER-WATER INSTABILITY WITH DELTA T/S OVER
15C. SOUNDINGS FOR MQT FROM GFS/NAM INDICATE WBZERO HEIGHTS STAYING
AOA 1000FT AGL SO KEPT PTYPE AS ONLY RAIN. EVEN WITH CYCLONIC
NORTHERLY FLOW IN WAKE OF SFC LOW MOVING INTO QUEBEC...SOUNDINGS
SHOW ONLY A SHALLOW MOIST LAYER AFTER 12Z MONDAY WITH TEMPS IN THE
MOIST LAYER NOT ANY COLDER THAN -5C. SO...MAY JUST END UP WITH
FINE DRIZZLE OR MAYBE JUST A FEW SPRINKLES SINCE SUB CLOUD LAYER IS
INCREASINLY MIXED WITH INVERTED-V LOOK.
SFC RIDGE FOLLOWING IN WAKE OF THE SFC LOW SHOULD BE IN PROCESS OF
WORKING ACROSS UPPER GREAT LAKES BY AFTN WHICH WILL CONK OUT ANY
LINGERING RAIN SHOWERS/DRIZZLE/SPRINKLES. CLOUDS USUALLY TOUGHER TO
GO AND WOULD EXPECT SCT-BKN STRATOCU TO HANG AROUND TIL LATER AFTN
AS H85 RIDGE BEGINS TO MOVE INTO THE AREA.
UPPER FLOW BECOMES MORE WESTERLY INTO TUESDAY ALLOWING WEAK SFC
TROUGH/WARM FRONT TO SKIRT ACROSS NORTHERN ONTARIO AND UPPER GREAT
LAKES. ALTHOUGH SFC REFLECTION IS WEAK...ACTUALLY IS STRONG WARM AIR
ADVECTION ALOFT WITH THE AHEAD AND ALONG SHORTWAVE PASSING OVER THE
REGION. ISENTROPIC ASCENT ON THE 300K SFC /H8-H7/ IMPACTS MOST OF
CWA...BUT STRONGEST H85 TEMP ADVECTION IS MORE OVER THE NORTH CWA.
OVERALL A PERIOD OF MOISTURE/STRONG UVM IN THE H7-H5 LAYER /TEMPS
BLO -10C/ ARE FORECAST WHICH SHOULD IN TURN LEAD TO GREATER CHANCE
OF SEEING SOME RAIN MAKE IT TO SFC DESPITE DRY SUB H85 LAYERS MODELS
SHOW. LOOKS LIKE HIGHER POP/LOW QPF SETUP. INCREASED POPS TO LIKELY
OVER NORTH AND ALSO EAST. HIGH CHANCES SHOULD COVER IT FOR AREAS
FARTHER AWAY FROM MID LEVEL LIFT. MID LEVEL MOISTURE/UVM EXITS TO
THE FAR EAST CWA BY LATE DAY...SO HAVE TRIMMED BACK POPS IN THE WEST
AFTER 18Z AND FOR ALL AREAS ON INTO TUESDAY NIGHT. DESPITE
CLOUDS/SHOWERS...WARMING TEMPS ALOFT AND A SOUTH WIND SHOULD ALLOW
FOR TEMPS TO PUSH ABOVE NORMAL...ESPECIALLY DURING AFTN AS PRECIP
TAPERS OFF. COULD SEE SOME SPOTS ON TUESDAY TOUCH 60 DEGREES IF
ENOUGH THINNING IN OVERCAST OCCURS. BEST SHOT FOR WARMER TEMPS IN
THE WEST AND SOUTHWEST CWA.
ATTENTION TUESDAY NIGHT INTO WEDNESDAY WILL BE ON SHORTWAVE TROUGH
AND STRONG UPPER LEVEL JET DIGGING INTO PACIFIC NORTHWEST.
ASSOCIATED SFC LOW /PRETTY DEEP AT SUB 985MB/ FORMS OVER SOUTHERN
ALBERTA LATER TUESDAY WITH COMPLEX OF LOWS THEN DEVELOPING FROM
SASKATCHEWAN INTO MINNESOTA AND WESTERN WISCONSIN BY LATE DAY ON
WEDNESDAY. SLIGHT POTENTIAL FOR COUPLE BATCHES OF MID LEVEL MOISTURE
LIFTING ACROSS TUESDAY NIGHT TO YIELD SPRINKLES OR A SHOWER ON
TUESDAY NIGHT. FOR MOST PART THOUGH THE NIGHT SHOULD END UP DRY
AND FAIRLY MILD FOR MID-LATE OCTOBER WITH LOWS IN THE MID-UPPER 40S.
NOW SEEMS LIKE WEDNESDAY WILL BE FOR MOST PART FAIRLY VOID OF SIG
PRECIP OVER THE CWA. UPPER TROUGH AND IDEAL JET SUPPORT FOR PRECIP
REMAIN WELL TO WEST OVER MIDDLE MISSISSIPPI RIVER VALLEY. ALSO
SOME INDICATION FROM LATEST ECMWF THAT SHARPER SHORTWAVE EMBEDDED IN
SOUTHERN PORTION OF UPR TROUGH WILL FOCUS SFC LOW FARTHER SOUTH OVER
SOUTHERN IOWA WHICH KEEPS H85 JET AND HIGHER H85 DWPNT LOCKED UP
MORE TO SOUTHWEST OF CWA. KEPT CHANCE POPS OVER WEST AND SOUTHWEST
CWA...BUT DID TRIM TO ONLY SLIGHT CHANCES OVER THE EASTERN CWA.
SIMILAR TO TUESDAY...GIVEN WARM AIR ALOFT /H85 TEMPS PUSHING +10C
OVER SOUTH CWA/ AND SOUTHERLY WINDS...MAX TEMPS COULD PUSH PAST 60
DEGREES AGAIN. TRENDS IN CLOUD COVER WILL HAVE BIG IMPACT ON TEMPS
THOUGH AS IF PARTIAL CLEARING COULD OCCUR OVER CWA...TEMPS MAKING
RUN WELL INTO THE 60S /EVEN AN ISOLD 70 DEGREE READING/ WOULD BE
FEASIBLE.
BEYOND WEDNESDAY MODELS DIVERGE WITH HANDLING OF TROUGH AND SFC
LOW TO CLOSE THE WEEK. GFS BECOMES MORE PROGRESSIVE WITH LOW PUSHING
TOWARD LK MICHIGAN BY THURSDAY AFTERNOON WHILE ECMWF AND GEM-NHEM
SHOW MORE OF A SLOWER UPPER TROUGH PROGRESSION AND KEEP PRIMARY SFC
LOW LUMBERING MORE OVER SOUTHERN PORTION OF MINNESOTA THROUGH
THURSDAY. SFC LOW PLACEMENT PRETTY MUCH ALL OVER THE PLACE IN MORE
RECENT MODEL RUNS. SINCE THE SYSTEM IS VERY WRAPPED UP ON ALL
MODELS...POTENTIAL IS THERE FOR SIGNIFICANT DRY SLOTTING SOMETIME
THURSDAY INTO FRIDAY ALONG WITH MINOR SHORTWAVES ROTATING AROUND
MAIN UPPER LOW. LEANED HEAVILY ON CONSENSUS FOR POPS/SKY/WINDS FOR
THURSDAY AND BEYOND DUE TO LACK OF CONSISTENCY IN ANY OF THE MODELS
AND VARYING SOLUTIONS WITH HANDLING OF UPPER TROUGH/SFC LOW. COULD
EASILY SEE WINDS BEING MUCH STRONGER THAN IS SHOWN WITH THIS
FORECAST...ESPECIALLY THURSDAY AND FRIDAY...BUT AT THIS POINT
CANNOT PIN POINT WHERE THE STRONGER WINDS WILL OCCUR.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 740 AM EDT SUN OCT 14 2012
LOW PRESSURE OVER THE CENTRAL PLAINS WILL MOVE NORTHEAST TOWARD THE
CENTRAL GREAT LAKES DURING THE FCST PERIOD. AT KIWD...IFR WILL
CONTINUE MUCH OF THE FCST PD WITH SOME -DZ DVLPG BY LATE MORNING IN
UPSLOPE NRLY FLOW. AT KCMX...MVFR CONDITIONS SHOULD GENERALLY
PREVAIL THROUGH PD UNDER NRLY FLOW. AT KSAW...LOW MVFR CONDITIONS
WILL FALL BACK TO LIFR CONDITIONS LATER THIS MORNING AS SHOWERS/RAIN
MOVE IN AND UPSLOPE NNE WINDS STRENGTHEN. DRIER AIR LATE TONIGHT IN
NNW SHOULD ALLOW CONDITIONS TO IMPROVE TO MVFR AGAIN.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 610 AM EDT SUN OCT 14 2012
EXPECT N TO NE WINDS TO INCREASE TODAY AS LOW PRES OVER THE CENTRAL
PLAINS LIFTS NE INTO NRN LWR MICHIGAN THIS AFTERNOON. DURING THE
AFTN...WINDS SHOULD BE IN THE 20-30KT RANGE OVER THE CNTRL AND ERN
PORTIONS OF LAKE SUPERIOR. WINDS WILL BE LIGHTER OVER THE FAR W.
EXPECT NORTHERLY GALES TO DEVELOP OVER EASTERN LAKE SUPERIOR THIS
EVENING AND THEN CONTINUE INTO MONDAY MORNING AS THE LOW RAPIDLY
DEEPENS AND MOVES EAST OF THE AREA AND HIGH PRESSURE PUSHES IN FROM
THE WEST. WINDS SETTLE DOWN MONDAY AFTERNOON AND MONDAY NIGHT WITH
ARRIVAL OF HIGH PRESSURE. ANOTHER LOW PRESSURE WILL MOVE INTO THE
UPPER GREAT LAKES ON WEDNESDAY. SOUTH WINDS AHEAD OF THIS LOW COULD
BRIEFLY REACH GALES TO 35 KTS OVER ERN LAKE SUPERIOR TUE AFTERNOON.
OTHERWISE...WINDS IN THE VICINITY OF THE LOW SHOULD REMAIN LESS THAN
20 KTS WEDNESDAY INTO THURSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 7 PM THIS EVENING TO 10 AM EDT MONDAY FOR
LSZ266-267.
LAKE MICHIGAN...
GALE WARNING FROM 6 PM THIS EVENING TO 11 AM EDT MONDAY FOR
LMZ221-250.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...VOSS
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
611 AM EDT SUN OCT 14 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 610 AM EDT SUN OCT 14 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS CONTINUE TO SHOW A ZONAL FLOW
ACROSS SRN CANADA AND THE FAR NRN CONUS WITH A WELL-DEFINED
SHORTWAVE OVER ERN KS AND WRN MO POISED TO LIFT NE TOWARD THE
CENTRAL GREAT LAKES THIS AFTERNOON. DEFORMATION/FRONTOGENESIS RAIN
BAND IN DEVELOPING BAROCLINIC LEAF/COMMA HEAD OF SHORTWAVE
STRETCHING FROM ERN NEBRASKA AND NRN IA INTO CENTRAL WI LINES UP
NICELY WITH 700 MB FGEN FORCING AS DEPICTED BY 00Z GFS. SO FAR EARLY
THIS MORNING...RADAR SHOW ONLY SPURIOUS SHRA ACTIVITY MOVING ACROSS
SCNTRL AND SE UPR MI IN AREA OF WEAK Q-VECT CONV AND FGEN FORCING.
THERE HAS ALSO BEEN SOME UPSLOPE DZ AT KMQT EARLY THIS MORNING IN
NRLY FLOW.
PCPN TRENDS/COVERAGE WILL BE THE MAIN FCST ISSUES IN THE SHORT TERM.
ZONAL FLOW ACROSS SRN CANADA/FAR NRN CONUS IS EXPECTED TO BUCKLE
TODAY AS HEIGHT RISES OVER WRN NAMERICA FORCE DOWNSTREAM HEIGHT
FALLS INTO MISSISSIPPI VALLEY REGION. THIS WILL HELP EJECT THE
CENTRAL PLAINS SHORTWAVE NE INTO THE GREAT LAKES THIS AFTERNOON.
EXACTLY HOW FAR N THE SHORTWAVE LIFTS ACROSS LOWER MI WILL BE
IMPORTANT TO THE PCPN COVERAGE TODAY. EVEN NOW...SO CLOSE TO THE
ONSET OF THE EVENT...THE MODELS ARE STILL EXHIBITING SIGNIFICANT RUN
TO RUN DIFFERENCES. THE MAJORITY OF THE 00Z RUNS WERE SHOWING THE
MAIN PCPN BAND STAYING MAINLY SOUTH OF THE FCST AREA...BRUSHING THE
FAR SCNTRL AND ERN FCST AREA WITH AROUND A HALF INCH OF RAINFALL
WITH A FAIRLY SHARP CUT-OFF OF PCPN HEADING NORTH AND WEST. NOW THE
06Z NAM AND GFS HAVE TRENDED FARTHER NORTH AND WEST WITH PCPN
SHIELD...STILL DROPPING THE HEAVIEST RAIN OVER THE SCNTRL AND EAST
BUT ALSO BRINGING ANYWHERE FROM 0.25-0.50 INCH INTO DICKINSON AND SE
HALF OF MQT COUNTY.
LATEST RADAR TRENDS AND MODEL FGEN FIELDS SUGGEST A SLIGHT NORTHWARD
TREND IN MAIN PCPN BAND IS POSSIBLE AS SHORTWAVE LIFTS TOWARD REGION
TODAY AND THIS WILL BE SOMETHING TO WATCH AS THE MORNING PROGRESSES.
SHORT TERM FCST UPDATES MAY NEED TO EXPAND CATEGORICAL POPS OVER FAR
SCNTRL AND ERN FCST AREA FARTHER NW TO ACCOUNT FOR THESE PCPN
TRENDS.
TONIGHT...AS SHORTWAVE AND ASSOC SFC LOW LIFT EAST OF THE REGION
LATER TONIGHT...EXPECT PCPN TO TAPER OFF OVER CENTRAL PORTIONS OF
THE CWA THIS EVENING AND OVER ERN PORTIONS OVERNIGHT. WITH MARGINAL
COLD ADVECTION BEHIND THE SYSTEM TONIGHT...AND BUFR SNDGS AND WET
BULB ZERO HGTS NOT REALLY SUPPORTING MUCH IN THE WAY OF PCPN
MIXING/CHANGING TO SNOW LATE TONIGHT...HAVE DECIDED TO PULL MENTION
OF SNOW LATE TONIGHT FOR NCNTRL ZONES. STRONG DEEP CYCLONIC NRLY
FLOW WILL LIKELY SUPPORT SOME LAKE EFFECT UPSLOPE RAIN/DZ THROUGH
MUCH OF NIGHT OVER NCNTRL PORTIONS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 610 AM EDT SUN OCT 14 2012
UPPER LEVEL PATTERN TO BEGIN THE LONG TERM ON MONDAY HAS A TROUGH
FROM HUDSON BAY INTO THE OHIO VALLEY WITH ASSOCIATED SFC LOW LIFTING
INTO SOUTHERN QUEBEC. KEPT MENTION OF LIGHT LK EFFECT PRECIP FIRST
THING ON MONDAY MORNING OVER NORTH CENTRAL WITH H85 TEMPS DOWN TO
-3C LEADING TO MARGINAL OVER-WATER INSTABILITY WITH DELTA T/S OVER
15C. SOUNDINGS FOR MQT FROM GFS/NAM INDICATE WBZERO HEIGHTS STAYING
AOA 1000FT AGL SO KEPT PTYPE AS ONLY RAIN. EVEN WITH CYCLONIC
NORTHERLY FLOW IN WAKE OF SFC LOW MOVING INTO QUEBEC...SOUNDINGS
SHOW ONLY A SHALLOW MOIST LAYER AFTER 12Z MONDAY WITH TEMPS IN THE
MOIST LAYER NOT ANY COLDER THAN -5C. SO...MAY JUST END UP WITH
FINE DRIZZLE OR MAYBE JUST A FEW SPRINKLES SINCE SUB CLOUD LAYER IS
INCREASINLY MIXED WITH INVERTED-V LOOK.
SFC RIDGE FOLLOWING IN WAKE OF THE SFC LOW SHOULD BE IN PROCESS OF
WORKING ACROSS UPPER GREAT LAKES BY AFTN WHICH WILL CONK OUT ANY
LINGERING RAIN SHOWERS/DRIZZLE/SPRINKLES. CLOUDS USUALLY TOUGHER TO
GO AND WOULD EXPECT SCT-BKN STRATOCU TO HANG AROUND TIL LATER AFTN
AS H85 RIDGE BEGINS TO MOVE INTO THE AREA.
UPPER FLOW BECOMES MORE WESTERLY INTO TUESDAY ALLOWING WEAK SFC
TROUGH/WARM FRONT TO SKIRT ACROSS NORTHERN ONTARIO AND UPPER GREAT
LAKES. ALTHOUGH SFC REFLECTION IS WEAK...ACTUALLY IS STRONG WARM AIR
ADVECTION ALOFT WITH THE AHEAD AND ALONG SHORTWAVE PASSING OVER THE
REGION. ISENTROPIC ASCENT ON THE 300K SFC /H8-H7/ IMPACTS MOST OF
CWA...BUT STRONGEST H85 TEMP ADVECTION IS MORE OVER THE NORTH CWA.
OVERALL A PERIOD OF MOISTURE/STRONG UVM IN THE H7-H5 LAYER /TEMPS
BLO -10C/ ARE FORECAST WHICH SHOULD IN TURN LEAD TO GREATER CHANCE
OF SEEING SOME RAIN MAKE IT TO SFC DESPITE DRY SUB H85 LAYERS MODELS
SHOW. LOOKS LIKE HIGHER POP/LOW QPF SETUP. INCREASED POPS TO LIKELY
OVER NORTH AND ALSO EAST. HIGH CHANCES SHOULD COVER IT FOR AREAS
FARTHER AWAY FROM MID LEVEL LIFT. MID LEVEL MOISTURE/UVM EXITS TO
THE FAR EAST CWA BY LATE DAY...SO HAVE TRIMMED BACK POPS IN THE WEST
AFTER 18Z AND FOR ALL AREAS ON INTO TUESDAY NIGHT. DESPITE
CLOUDS/SHOWERS...WARMING TEMPS ALOFT AND A SOUTH WIND SHOULD ALLOW
FOR TEMPS TO PUSH ABOVE NORMAL...ESPECIALLY DURING AFTN AS PRECIP
TAPERS OFF. COULD SEE SOME SPOTS ON TUESDAY TOUCH 60 DEGREES IF
ENOUGH THINNING IN OVERCAST OCCURS. BEST SHOT FOR WARMER TEMPS IN
THE WEST AND SOUTHWEST CWA.
ATTENTION TUESDAY NIGHT INTO WEDNESDAY WILL BE ON SHORTWAVE TROUGH
AND STRONG UPPER LEVEL JET DIGGING INTO PACIFIC NORTHWEST.
ASSOCIATED SFC LOW /PRETTY DEEP AT SUB 985MB/ FORMS OVER SOUTHERN
ALBERTA LATER TUESDAY WITH COMPLEX OF LOWS THEN DEVELOPING FROM
SASKATCHEWAN INTO MINNESOTA AND WESTERN WISCONSIN BY LATE DAY ON
WEDNESDAY. SLIGHT POTENTIAL FOR COUPLE BATCHES OF MID LEVEL MOISTURE
LIFTING ACROSS TUESDAY NIGHT TO YIELD SPRINKLES OR A SHOWER ON
TUESDAY NIGHT. FOR MOST PART THOUGH THE NIGHT SHOULD END UP DRY
AND FAIRLY MILD FOR MID-LATE OCTOBER WITH LOWS IN THE MID-UPPER 40S.
NOW SEEMS LIKE WEDNESDAY WILL BE FOR MOST PART FAIRLY VOID OF SIG
PRECIP OVER THE CWA. UPPER TROUGH AND IDEAL JET SUPPORT FOR PRECIP
REMAIN WELL TO WEST OVER MIDDLE MISSISSIPPI RIVER VALLEY. ALSO
SOME INDICATION FROM LATEST ECMWF THAT SHARPER SHORTWAVE EMBEDDED IN
SOUTHERN PORTION OF UPR TROUGH WILL FOCUS SFC LOW FARTHER SOUTH OVER
SOUTHERN IOWA WHICH KEEPS H85 JET AND HIGHER H85 DWPNT LOCKED UP
MORE TO SOUTHWEST OF CWA. KEPT CHANCE POPS OVER WEST AND SOUTHWEST
CWA...BUT DID TRIM TO ONLY SLIGHT CHANCES OVER THE EASTERN CWA.
SIMILAR TO TUESDAY...GIVEN WARM AIR ALOFT /H85 TEMPS PUSHING +10C
OVER SOUTH CWA/ AND SOUTHERLY WINDS...MAX TEMPS COULD PUSH PAST 60
DEGREES AGAIN. TRENDS IN CLOUD COVER WILL HAVE BIG IMPACT ON TEMPS
THOUGH AS IF PARTIAL CLEARING COULD OCCUR OVER CWA...TEMPS MAKING
RUN WELL INTO THE 60S /EVEN AN ISOLD 70 DEGREE READING/ WOULD BE
FEASIBLE.
BEYOND WEDNESDAY MODELS DIVERGE WITH HANDLING OF TROUGH AND SFC
LOW TO CLOSE THE WEEK. GFS BECOMES MORE PROGRESSIVE WITH LOW PUSHING
TOWARD LK MICHIGAN BY THURSDAY AFTERNOON WHILE ECMWF AND GEM-NHEM
SHOW MORE OF A SLOWER UPPER TROUGH PROGRESSION AND KEEP PRIMARY SFC
LOW LUMBERING MORE OVER SOUTHERN PORTION OF MINNESOTA THROUGH
THURSDAY. SFC LOW PLACEMENT PRETTY MUCH ALL OVER THE PLACE IN MORE
RECENT MODEL RUNS. SINCE THE SYSTEM IS VERY WRAPPED UP ON ALL
MODELS...POTENTIAL IS THERE FOR SIGNIFICANT DRY SLOTTING SOMETIME
THURSDAY INTO FRIDAY ALONG WITH MINOR SHORTWAVES ROTATING AROUND
MAIN UPPER LOW. LEANED HEAVILY ON CONSENSUS FOR POPS/SKY/WINDS FOR
THURSDAY AND BEYOND DUE TO LACK OF CONSISTENCY IN ANY OF THE MODELS
AND VARYING SOLUTIONS WITH HANDLING OF UPPER TROUGH/SFC LOW. COULD
EASILY SEE WINDS BEING MUCH STRONGER THAN IS SHOWN WITH THIS
FORECAST...ESPECIALLY THURSDAY AND FRIDAY...BUT AT THIS POINT
CANNOT PIN POINT WHERE THE STRONGER WINDS WILL OCCUR.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 213 AM EDT SUN OCT 14 2012
LOW PRESSURE OVER THE CENTRAL PLAINS WILL MOVE NORTHEAST TOWARD THE
WRN GREAT LAKES DURING THE FCST PERIOD. AT KIWD...WILL CONTINUE TO
SEE VLIFR CONDITIONS/-DZ LATER TONIGHT AS NNE WINDS STRENGTHEN
ACROSS LAKE SUPERIOR FOR SOME UPSLOPE. DRIER AIR GETS ADVECTED IN BY
AFTERNOON WITH MVFR CONDITIONS EXPECTED THROUGH THE REST OF THE
PERIOD AT KIWD. AT KCMX...MVFR CONDITIONS SHOULD GENERALLY PREVAIL
OVERNIGHT INTO SUNDAY IN MOSTLY DOWNSLOPE NE FLOW. AT KSAW...LOW
MVFR CONDITIONS WILL FALL BACK TO LIFR CONDITIONS LATER TONIGHT/SUN
AS UPSLOPE NNE WINDS STRENGTHEN. DRIER AIR LATE IN THE AFTERNOON
SHOULD BRING MVFR CONDITIONS TO KSAW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 610 AM EDT SUN OCT 14 2012
EXPECT N TO NE WINDS TO INCREASE TODAY AS LOW PRES OVER THE CENTRAL
PLAINS LIFTS NE INTO NRN LWR MICHIGAN THIS AFTERNOON. DURING THE
AFTN...WINDS SHOULD BE IN THE 20-30KT RANGE OVER THE CNTRL AND ERN
PORTIONS OF LAKE SUPERIOR. WINDS WILL BE LIGHTER OVER THE FAR W.
EXPECT NORTHERLY GALES TO DEVELOP OVER EASTERN LAKE SUPERIOR THIS
EVENING AND THEN CONTINUE INTO MONDAY MORNING AS THE LOW RAPIDLY
DEEPENS AND MOVES EAST OF THE AREA AND HIGH PRESSURE PUSHES IN FROM
THE WEST. WINDS SETTLE DOWN MONDAY AFTERNOON AND MONDAY NIGHT WITH
ARRIVAL OF HIGH PRESSURE. ANOTHER LOW PRESSURE WILL MOVE INTO THE
UPPER GREAT LAKES ON WEDNESDAY. SOUTH WINDS AHEAD OF THIS LOW COULD
BRIEFLY REACH GALES TO 35 KTS OVER ERN LAKE SUPERIOR TUE AFTERNOON.
OTHERWISE...WINDS IN THE VICINITY OF THE LOW SHOULD REMAIN LESS THAN
20 KTS WEDNESDAY INTO THURSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 7 PM THIS EVENING TO 10 AM EDT MONDAY FOR
LSZ266-267.
LAKE MICHIGAN...
GALE WARNING FROM 6 PM THIS EVENING TO 11 AM EDT MONDAY FOR
LMZ221-250.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...07
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
217 AM EDT SUN OCT 14 2012
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 423 PM EDT SAT OCT 13 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A ZONALLY ORIENTED FLOW
ACROSS SRN CANADA AND THE FAR NRN CONUS. TO THE S...A SHORTWAVE TROF
IS EMERGING FROM CO/NM INTO THE WRN PLAINS. DEEP/MOIST SW FLOW
DOWNSTREAM OF THE TROF HAS GENERATED SEVERAL AREAS OF SHRA AND SOME
TSRA FROM THE SRN PLAINS TO THE GREAT LAKES. WITH THE MORE ZONALLY
ORIENTED FLOW ACROSS THE FAR NRN CONUS...THE AREAS OF SHRA HAVE BEEN
TENDING TO SHIFT MORE EASTWARD THE FARTHER N THEY SPREAD. AS A
RESULT...THERE HAS BEEN LITTLE PCPN OVER THE NW HALF OF THE FCST
AREA TODAY (MUCH OF THE PCPN HAS BEEN DRIZZLE) WHILE THE SE HALF HAS
BEEN GETTING BRUSHED BY SHRA.
PCPN TRENDS/COVERAGE WILL BE THE MAIN FCST ISSUES IN THE SHORT TERM.
FLOW ACROSS SRN CANADA/FAR NRN CONUS IS EXPECTED TO BUCKLE AS HEIGHT
RISES OVER WRN NAMERICA FORCE DOWNSTREAM HEIGHT FALLS INTO
MISSISSIPPI VALLEY REGION. THIS WILL HELP TO PICK UP/LIFT THE WRN
PLAINS SHORTWAVE TO THE NE. EXACTLY HOW FAR N IT LIFTS WILL BE
IMPORTANT TO THE PCPN FCST TONIGHT/SUN. EVEN AT THIS SHORT TIME
RANGE INTO MODEL RUNS...THERE ARE STILL IMPORTANT DIFFERENCES IN THE
MODELS. THE NAM REMAINS MOST SUPPRESSED WITH THE LOW TRACK THOUGH IT
HAS TRENDED SLIGHTLY N...AND IT IS SUPPORTED BY OUR LOCAL REG WRF
RUN AND THE NCEP HIGH RES WRF-ARW AND WRF-NMN. THEY ALL KEEP THE
MAIN PCPN SHIELD ALMOST ENTIRELY SE OF FCST AREA SUN. THE 12Z GFS
HAS TRENDED S AND ONLY BRINGS PCPN SHIELD INTO THE SE FCST AREA. THE
UKMET/REGIONAL GEM PUSH PCPN SHIELD A LITTLE FARTHER N AND W. THE 12Z
ECMWF HAS ALSO TRENDED SLIGHTLY S. GIVEN OVERALL TRENDS AND A
MAJORITY SHOWING A LESS AGGRESSIVE MOISTURE PUSH INTO UPPER MI
SUN...FCST WILL FOLLOW SUIT AND SHOW HIGHER POPS SHIFTED MORE TO THE
S AND E.
CURRENT PUSH OF SHRA ENE THRU WI INTO SRN UPPER MI IS ASSOCIATED
WITH A SURGE OF 850-700MB MOISTURE TRANSPORT AND ISENTROPIC ASCENT
ON THE 305K SFC. WITH THAT MOISTURE TRANSPORT/ASCENT QUICKLY
SHIFTING E THIS EVENING...AND THEN RATHER MEAGER FORCING LEFT BEHIND
FOR THE NIGHT...IT APPEARS THERE WON`T BE MUCH IN THE WAY OF
RAINFALL FOR THE BULK OF TONIGHT AS WE AWAIT THE MAIN PIECE OF
ENERGY TO TRACK INTO THE GREAT LAKES SUN. WITH WINDS BECOMING LIGHT
UPSLOPE OFF LAKE SUPERIOR DURING THE NIGHT...-DZ THAT HAS BEEN
OCCURRING TODAY WILL LIKELY CONTINUE TONIGHT...ESPECIALLY ACROSS THE
NCNTRL.
SHORTWAVE LIFTS INTO THE GREAT LAKES SUN AFTN WITH ASSOCIATED SFC
LOW TRACKING TOWARD NRN LWR MI. AS A RESULT...RAIN WILL SPREAD BACK
TO THE N...BUT AS DISCUSSED ABOVE...LOWERED POPS FROM PREVIOUS FCST.
KEPT CATEGORICAL POPS ONLY ALONG LAKE MICHIGAN INTO THE FAR ERN FCST
AREA WITH POPS DROPPING OFF SHARPLY TO CHC JUST TO THE NW. MAY SEE A
LITTLE LAKE ENHANCED SHRA ACTIVITY IN THE NNE/NE WIND FAVORED
LOCATIONS...SO SHRA CHANCES IN THOSE AREAS WILL BE A LITTLE HIGHER.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 423 PM EDT SAT OCT 13 2012
A FAIRLY STRONG UPPER SHORTWAVE TROUGH WILL BE OVER THE CENTRAL CWA
AT 00Z MON...DEEPENING AS IT MOVES TO THE FAR ERN CWA BY 06Z MON DUE
TO A WEAK SHORTWAVE PHASING WITH THE SYSTEM. AT THE SFC...A ROUGHLY
995MB LOW WILL BE OVER OVER NRN LOWER MI AT 00Z MON...MOVING TO
GEORGIAN BAY BY 06Z MON. THE 850MB LOW WILL BE JUST E OF DRUMMOND
ISLAND AT 00Z MON...WITH A NICE DEFORMATION PRECIP BAND JUST ON THE
LEFT SIDE OF THE 850MB LOW TRACK AS IT MOVES NE. THERE SHOULD BE A
PRETTY SHARP CUT OFF BETWEEN THE DEFORMATION BAND AND LITTLE TO NO
SYNOPTIC RAIN...AND AFTER 00Z SUN...THE CWA SHOULD BE ON THE DRIER
SIDE OF THAT CUT OFF. HOWEVER...WITH THE SHORTWAVE DEEPENING
OVERHEAD THEN MOVING E...COLDER 850MB TEMPS WILL FILTER IN FROM THE
NNW. WITH THE NNW LOW LEVEL WINDS AND 850MB TEMPS OF -3C TO
-4C...SOME LIGHT LAKE EFFECT RAIN /MIXING WITH SNOW OVER THE HIGHER
TERRAIN/ WILL LINGER INTO MONDAY MORNING OVER NCENTRAL AND ERN UPPER
MI.
A SFC RIDGE WILL MOVE OVER MON AFTERNOON AND EVENING...BRINGING A
BRIEF DRY PERIOD BEFORE A SHORTWAVE TROUGH AND ASSOCIATED WARM FRONT
MOVE INTO THE CWA. PRECIP CHANCES MOVE BACK IN WITH THIS SYSTEM
AFTER MIDNIGHT MON NIGHT...WITH AT LEAST SLIGHT CHANCE POPS OVER
PARTS OF THE CWA UNTIL MORE PRECIP ARRIVES WITH A LOW PRESSURE
SYSTEM MOVING IN FROM THE W ON WED. HIGHS ON MON LOOK TO BE IN THE
UPPER 40S TO MID 50...WITH WARMER TEMPS ON TUE IN THE 50S. WED LOOKS
TO CONTINUE THE WARM TREND WITH HIGHS AGAIN IN THE 50S. OVERALL GOOD
CONFIDENCE INTO WED.
CONFIDENCE DECREASES AS THE NEXT SYSTEM MOVES IN WED INTO THE END OF
NEXT WEEK SINCE MODELS GENERALLY SHOW THE SAME IDEA OF THE LOW
CLOSING OFF ON THU AND LINGERING SOMEWHERE OVER/NEAR THE REGION
THROUGH THE END OF THE WEEK. HOWEVER...MODELS SHOW SIGNIFICANTLY
VARYING SOLUTIONS WITH WHERE TO HAVE THE LOW...WHICH CAUSES WIDELY
DIFFERENT PRECIP/WIND SCENARIOS. EVEN WITH THE DIFFERENCES...WILL
HAVE CHANCES OF PRECIP FOR THE REST OF THE PERIOD LATE WED THROUGH
SAT...DERIVED FROM CONSENSUS OF MODELS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 213 AM EDT SUN OCT 14 2012
LOW PRESSURE OVER THE CENTRAL PLAINS WILL MOVE NORTHEAST TOWARD THE
WRN GREAT LAKES DURING THE FCST PERIOD. AT KIWD...WILL CONTINUE TO
SEE VLIFR CONDITIONS/-DZ LATER TONIGHT AS NNE WINDS STRENGTHEN
ACROSS LAKE SUPERIOR FOR SOME UPSLOPE. DRIER AIR GETS ADVECTED IN BY
AFTERNOON WITH MVFR CONDITIONS EXPECTED THROUGH THE REST OF THE
PERIOD AT KIWD. AT KCMX...MVFR CONDITIONS SHOULD GENERALLY PREVAIL
OVERNIGHT INTO SUNDAY IN MOSTLY DOWNSLOPE NE FLOW. AT KSAW...LOW
MVFR CONDITIONS WILL FALL BACK TO LIFR CONDITIONS LATER TONIGHT/SUN
AS UPSLOPE NNE WINDS STRENGTHEN. DRIER AIR LATE IN THE AFTERNOON
SHOULD BRING MVFR CONDITIONS TO KSAW. &&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 423 PM EDT SAT OCT 13 2012
WINDS ARE IN THE PROCESS OF DIMINISHING ACROSS LAKE SUPERIOR AS LOW
PRES TROF/WEAKER PRES GRADIENT SHIFT OVER THE AREA. LATER TONIGHT
AND INTO SUN...N TO NE WINDS WILL INCREASE AS LOW PRES MOVES NE
TOWARD NRN LWR MICHIGAN. DURING SUN AFTN...WINDS SHOULD BE IN THE
20-30KT RANGE OVER THE CNTRL AND ERN PORTIONS OF LAKE SUPERIOR.
WINDS WILL BE LIGHTER OVER THE FAR W. SOME NORTHERLY GALE GUSTS OVER
EASTERN LAKE SUPERIOR ARE POSSIBLE INTO SUNDAY NIGHT AS THE LOW
MOVES EAST OF THE AREA AND HIGH PRESSURE PUSHES IN FROM THE WEST.
WINDS SETTLE DOWN MONDAY AND MONDAY NIGHT WITH ARRIVAL OF HIGH
PRESSURE. ANOTHER LOW PRESSURE WILL MOVE INTO THE UPPER GREAT LAKES
ON WEDNESDAY. SOUTH WINDS COULD PUSH UP TO 25 KTS AHEAD OF THE LOW
ON TUESDAY...MAINLY FOR EASTERN SECTIONS. OTHERWISE...WINDS IN THE
VICINITY OF THE LOW SHOULD REMAIN LESS THAN 20 KTS WEDNESDAY INTO
THURSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...07
MARINE...ROLFSON/TITUS
AREA FORECAST DISCUSSION
NWS JACKSON MS
420 PM CDT SUN OCT 14 2012
.SHORT TERM...
SHOWERS/THUNDERSTORM ACTIVITY ASSOCIATED WITH THE PREFRONTAL TROUGH
HAS ALL BUT DIMINISHED ACROSS THE ARKLAMISS THIS AFTERNOON LEAVING
JUST A FEW LIGHT SHOWERS PASSING OVER AREAS S OF THE NATCHEZ TRACE.
CLEARING CLOUD COVER ACROSS THE DELTA/NE LA HAS ALLOWED HEATING TO
WARM TEMPS INTO THE UPPER 70S/LOWER 80S ACCOMPANIED BY DEW POINTS IN
THE UPPER 60S/NEAR 70. LATEST RUC ANALYSIS SHOWS UNCAPPED SBCAPE
VALUES HAVE CLIMBED ABOVE 1500J/KG ACROSS THESE AREAS JUST AHEAD OF
THE COLD FRONT. FORCING ASSOCIATED WITH THE LEFT EXIT REGION OF A
STRENGTHENING UPPER JET STREAK NOSING IN FROM THE WEST WILL BEGIN TO
OVERSPREAD THESE UNSTABLE AREAS OVER THE NEXT 2 TO 3 HOURS AND WOULD
NOT BE SURPRISED IF AT LEAST A COUPLE STORMS DEVELOPED ALONG THE
FRONT AS WE HEAD INTO EVENING. DEEP LAYER SHEAR OF ~30KTS REMAINS
SUFFICIENT YET MARGINAL FOR SEVERE STORMS SO THE SEVERE WEATHER RISK
WITH ANY OF THIS ACTIVITY IS NOT A SLAM DUNK...BUT IS NOT OUT OF THE
QUESTION. WIND GUSTS WILL BE THE PRIMARY RISK IF ANYTHING CAN GET
GOING...BUT A TORNADO ISN`T COMPLETELY OUT OF THE QUESTION AS LOW
LEVEL SHEAR IN EXCESS OF 20KTS REMAINS ACROSS THIS REGION. WILL KEEP
THESE RISKS MENTIONED IN THE HWO THROUGH THE EVENING.
THE CONVECTIVE POTENTIAL HEADED INTO THE LATTER PART OF THE EVENING
WILL MOST LIKELY BE DOMINATED BY WHAT CAN GET GOING THROUGH EARLY
EVENING. IF STORMS DEVELOP THEN A FEW MAY PERSIST AND PUSH SE TOWARD
THE NATCHEZ TRACE CORRIDOR AS THE STRONG LIFT PUSHES IN...BUT IF
NOTHING DEVELOPS WE MAY NOT SEE MUCH PERSIST PAST 8 OR 9 PM. GIVEN
THE STRENGTH OF THE FORCING...ITS PLAUSIBLE WE COULD SEE ISOLATED
SHOWERS AHEAD OF THE FRONT THROUGH MOST OF THE NIGHT REGARDLESS.
HIGH PRESSURE IN WAKE OF THE FRONT WILL OVERSPREAD THE REGION
TOMORROW KEEPING THINGS DRY THROUGH THE MIDDLE OF THE WEEK. TEMPS
THROUGH THIS TIME WILL BE MUCH MORE SEASONAL ALTHOUGH HIGHS WILL
STILL BE COMING IN A TAD ABOVE NORMAL. RELEVANT SECTIONS OF THE
PREVIOUS LONGER TERM DISCUSSION HAVE BEEN APPENDED BELOW. /BK/
.LONG TERM...
BY WED...A VIGOROUS H5 S/WV TROUGH WILL PIVOT INTO THE CNTRL PLAINS.
DEEP SFC CYCLOGENESIS IS PROGGED TO OCCUR WITH A SUB 995MB SFC LOW
ACROSS MID/UPPER MS VALLEY THAT WILL BRING A POTENT COLD FRONT
TOWARDS THE REGION. AHEAD OF THE FRONT...PWATS WILL SURGE FROM S/SW
FLOW LATE WED/ERLY THURS TO NEAR 1.6-1.8" AS SFC DEWPOINTS CLIMB BACK
INTO THE LOW 60S.
ATTM...TIMING OF FROPA IS THURS MRNG PER 00Z EC/GFS WITH LOW
INSTABILITY BUT MODEST KINEMATICS. WILL HAVE TO KEEP WATCH OF THIS
SYSTEM IF SLOWER TIMING /AS 12Z ECMWF HINTED AT/ RESULTS IN GREATER
CONVECTIVE POTENTIAL IF FROPA OCCURS THURS AFTN. INCREASED POPS
ABOVE MEXMOS TOWARDS ECMEX VALUES THURS MRNG FOR NW AREAS WITH
DECREASING RAIN CHANCES BY THURS AFTN/NGT FROM NW TO SE. EC/GFS ARE
AT ODDS WITH DEGREE OF CAA AS EC KEEPS COOLER H85 TEMPS N/W OF
REGION WHILE GFS BARRELS SINGLE DIGIT H85 TEMPS ACROSS NRN ARKLAMISS
FRIDAY. HAVE FAVORED GFS GIVEN CONTINUED MEAN ENSEMBLE SUPPORT WITH
MEAN H5 TROUGH AXIS PLACEMENT JUXTAPOSED TO EC`S LONG RANGE H5
OMEGA BLOCK PATTERN. HIGHS FRI/SAT LOOK TO RANGE FROM NEAR 70 NORTH
TO MID 70S SOUTH WITH A SLIGHT WARM UP INTO SUNDAY WITH PROGGED
AMPLE SUNSHINE POST FROPA. /ALLEN/
&&
.AVIATION...THE CONVECTION ACROSS THE AREA THIS MORNING STABILIZED
THE AIRMASS BUT ADDITIONAL ACTIVITY WILL BE POSSIBLE ALONG A COLD
FRONT THAT WILL MOVE ACROSS THE AREA TONIGHT. EXPECT VFR CONDITIONS
OUTSIDE OF ANY TSTM ACTIVITY. THE COLD FRONT WILL PASS THROUGH THE
ENTIRE AREA BY DAYBREAK MONDAY AND EXPECT VFR CONDITIONS WILL
PREVAIL FOR THE ENTIRE AREA THROUGH MONDAY NIGHT AS HIGH PRESSURE
AND DRIER AIR BRINGS CLEAR SKIES. /22/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 57 79 49 78 / 23 0 0 5
MERIDIAN 59 80 45 77 / 23 0 0 3
VICKSBURG 53 80 46 78 / 27 0 0 5
HATTIESBURG 65 82 49 79 / 22 0 0 11
NATCHEZ 57 78 49 77 / 24 0 0 5
GREENVILLE 52 77 50 79 / 30 0 0 3
GREENWOOD 51 77 47 79 / 31 0 0 3
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
BK/22/ALLEN
AREA FORECAST DISCUSSION
NWS JACKSON MS
352 PM CDT SUN OCT 14 2012
.SHORT TERM...
SHOWERS/THUNDERSTORM ACTIVITY ASSOCIATED WITH THE PREFRONTAL TROUGH
HAS ALL BUT DIMINISHED ACROSS THE ARKLAMISS THIS AFTERNOON LEAVING
JUST A FEW LIGHT SHOWERS PASSING OVER AREAS S OF THE NATCHEZ TRACE.
CLEARING CLOUD COVER ACROSS THE DELTA/NE LA HAS ALLOWED HEATING TO
WARM TEMPS INTO THE UPPER 70S/LOWER 80S ACCOMPANIED BY DEW POINTS IN
THE UPPER 60S/NEAR 70. LATEST RUC ANALYSIS SHOWS UNCAPPED SBCAPE
VALUES HAVE CLIMBED ABOVE 1500J/KG ACROSS THESE AREAS JUST AHEAD OF
THE COLD FRONT. FORCING ASSOCIATED WITH THE LEFT EXIT REGION OF A
STRENGTHENING UPPER JET STREAK NOSING IN FROM THE WEST WILL BEGIN TO
OVERSPREAD THESE UNSTABLE AREAS OVER THE NEXT 2 TO 3 HOURS AND WOULD
NOT BE SURPRISED IF AT LEAST A COUPLE STORMS DEVELOPED ALONG THE
FRONT AS WE HEAD INTO EVENING. DEEP LAYER SHEAR OF ~30KTS REMAINS
SUFFICIENT YET MARGINAL FOR SEVERE STORMS SO THE SEVERE WEATHER RISK
WITH ANY OF THIS ACTIVITY IS NOT A SLAM DUNK...BUT IS NOT OUT OF THE
QUESTION. WIND GUSTS WILL BE THE PRIMARY RISK IF ANYTHING CAN GET
GOING...BUT A TORNADO ISN`T COMPLETELY OUT OF THE QUESTION AS LOW
LEVEL SHEAR IN EXCESS OF 20KTS REMAINS ACROSS THIS REGION. WILL KEEP
THESE RISKS MENTIONED IN THE HWO THROUGH THE EVENING.
THE CONVECTIVE POTENTIAL HEADED INTO THE LATTER PART OF THE EVENING
WILL MOST LIKELY BE DOMINATED BY WHAT CAN GET GOING THROUGH EARLY
EVENING. IF STORMS DEVELOP THEN A FEW MAY PERSIST AND PUSH SE TOWARD
THE NATCHEZ TRACE CORRIDOR AS THE STRONG LIFT PUSHES IN...BUT IF
NOTHING DEVELOPS WE MAY NOT SEE MUCH PERSIST PAST 8 OR 9 PM. GIVEN
THE STRENGTH OF THE FORCING...ITS PLAUSIBLE WE COULD SEE ISOLATED
SHOWERS AHEAD OF THE FRONT THROUGH MOST OF THE NIGHT REGARDLESS.
HIGH PRESSURE IN WAKE OF THE FRONT WILL OVERSPREAD THE REGION
TOMORROW KEEPING THINGS DRY THROUGH THE MIDDLE OF THE WEEK. TEMPS
THROUGH THIS TIME WILL BE MUCH MORE SEASONAL ALTHOUGH HIGHS WILL
STILL BE COMING IN A TAD ABOVE NORMAL. RELEVANT SECTIONS OF THE
PREVIOUS LONGER TERM DISCUSSION HAVE BEEN APPENDED BELOW. /BK/
.LONG TERM...
BY WED...A VIGOROUS H5 S/WV TROUGH WILL PIVOT INTO THE CNTRL PLAINS.
DEEP SFC CYCLOGENESIS IS PROGGED TO OCCUR WITH A SUB 995MB SFC LOW
ACROSS MID/UPPER MS VALLEY THAT WILL BRING A POTENT COLD FRONT
TOWARDS THE REGION. AHEAD OF THE FRONT...PWATS WILL SURGE FROM S/SW
FLOW LATE WED/ERLY THURS TO NEAR 1.6-1.8" AS SFC DEWPOINTS CLIMB BACK
INTO THE LOW 60S.
ATTM...TIMING OF FROPA IS THURS MRNG PER 00Z EC/GFS WITH LOW
INSTABILITY BUT MODEST KINEMATICS. WILL HAVE TO KEEP WATCH OF THIS
SYSTEM IF SLOWER TIMING /AS 12Z ECMWF HINTED AT/ RESULTS IN GREATER
CONVECTIVE POTENTIAL IF FROPA OCCURS THURS AFTN. INCREASED POPS
ABOVE MEXMOS TOWARDS ECMEX VALUES THURS MRNG FOR NW AREAS WITH
DECREASING RAIN CHANCES BY THURS AFTN/NGT FROM NW TO SE. EC/GFS ARE
AT ODDS WITH DEGREE OF CAA AS EC KEEPS COOLER H85 TEMPS N/W OF
REGION WHILE GFS BARRELS SINGLE DIGIT H85 TEMPS ACROSS NRN ARKLAMISS
FRIDAY. HAVE FAVORED GFS GIVEN CONTINUED MEAN ENSEMBLE SUPPORT WITH
MEAN H5 TROUGH AXIS PLACEMENT JUXTAPOSED TO EC`S LONG RANGE H5
OMEGA BLOCK PATTERN. HIGHS FRI/SAT LOOK TO RANGE FROM NEAR 70 NORTH
TO MID 70S SOUTH WITH A SLIGHT WARM UP INTO SUNDAY WITH PROGGED
AMPLE SUNSHINE POST FROPA. /ALLEN/
&&
.AVIATION...THE CONVECTION ACROSS THE AREA THIS MORNING STABILIZED
THE AIRMASS BUT ADDITIONAL ACTIVITY WILL BE POSSIBLE ALONG A COLD
FRONT THAT WILL MOVE ACROSS THE AREA TONIGHT. EXPECT VFR CONDITIONS
OUTSIDE OF ANY TSTM ACTIVITY. THE COLD FRONT WILL PASS THROUGH THE
ENTIRE AREA BY DAYBREAK MONDAY AND EXPECT VFR CONDITIONS WILL
PREVAIL FOR THE ENTIRE AREA THROUGH MONDAY NIGHT AS HIGH PRESSURE
AND DRIER AIR BRINGS CLEAR SKIES. /22/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 57 79 49 78 / 23 0 0 5
MERIDIAN 59 80 45 77 / 23 0 0 3
VICKSBURG 53 80 46 78 / 27 0 0 5
HATTIESBURG 65 82 49 79 / 22 0 0 11
NATCHEZ 57 78 49 77 / 24 0 0 5
GREENVILLE 52 77 50 79 / 30 0 0 3
GREENWOOD 51 77 47 79 / 31 0 0 3
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...WIND ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR MSZ018-019-034.
LA...NONE.
AR...WIND ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR ARZ075.
&&
$$
BK/22/ALLEN
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1147 PM CDT SAT OCT 13 2012
.AVIATION...
06Z TAFS FOR KOFK...KLNK AND KOMA.
GENERALLY VFR CONDITIONS ARE EXPECTED THROUGH SUNDAY EVENING
OUTSIDE OF ANY THUNDERSTORM ACTIVITY. SCATTERED THUNDERSTORMS WILL
AFFECT KLNK AND KOMA AREAS THROUGH ABOUT 09Z SATURDAY MORNING AS
A LOW PRESSURE SYSTEM AND COLD FRONT MOVE THROUGH THE AREA.
ASSOCIATED MVFR CIGS/VSBYS CAN BE EXPECTED. OTHERWISE NORTHWEST
WINDS WILL FOLLOW THE FRONT AND INCREASE TO THE 15 TO 30 KT RANGE
BY 15Z SUNDAY UNDER CLEAR SKIES. THOSE WINDS SHOULD DIMINISH TO
UNDER 10KT BY 00Z.
DERGAN
&&
.PREV DISCUSSION... /ISSUED 318 PM CDT SAT OCT 13 2012/
SHORT TERM...TONIGHT THROUGH TUESDAY
MUCH WARMER AND MOISTER AIR HAS REACHED THE REGION AHEAD OF AN
ADVANCING UPPER-LEVEL LOW. SUBJECTIVE 12Z UPPER AIR ANALYSIS
INDICATES OPENING UPPER LOW CENTERED IN SOUTHERN CO...WITH 500MB
HEIGHT FALLS UP TO 90M IN EASTERN CO INDICATING THE WAVE IS EJECTING
INTO THE CENTRAL PLAINS. CORE OF UPPER-LEVEL JET EXTENDED FROM GULF
OF CA THROUGH WESTERN KS/NEB AND INTO CENTRAL MN...WITH STRONGER
NORTHERN STREAM JET STREAK NOSING INTO THE PACIFIC NORTHWEST. AHEAD
OF THE UPPER LOW...850MB MOISTURE HAD SPREAD NORTHWARD FROM OK/TX
INTO NEB/IA...WITH 850MB WINDS UP TO 50-60KT IN EASTERN KS/EASTERN
NEB. SURFACE LOW AT 19Z WAS CENTERED IN NORTH CENTRAL NEB...WITH
COLD FRONT LAGGING FROM SOUTHWEST NEB THROUGH WESTERN KS TO THE
OK/TX PANHANDLES. SURFACE DEWPOINTS IN EASTERN NEB/WESTERN IA ALONG
AND SOUTH OF I-80 WERE IN THE 60S.
MAIN FORECAST CONCERN IS CONVECTIVE POTENTIAL THIS EVENING...WITH
RAIN LINGERING INTO TONIGHT IN THE SOUTHEASTERN CWA. THOUGH UPPER-
LEVEL WAVE IS OPENING...IT REMAINS POTENT. RAP ANALYSIS INDICATES
MLCAPE OF 1000+ J/KG REACHING SOUTH CENTRAL NEB. DEEP-LAYER
EFFECTIVE BULK SHEAR CERTAINLY IS POTENT...AT OR ABOVE 40KT ACROSS
MOST OF SOUTHEAST NEB/SOUTHWEST IA. INTERMITTENT CLOUDS HAVE BEEN
IN PLACE ALL ACROSS THE AREA...BUT ENOUGH SUN IS BREAKING THROUGH TO
ALLOW SOME HEATING AND DESTABILIZATION. THINK CONVECTION COULD
DEVELOP IN CENTRAL KS IN THE LATE AFTN...THEN MOVE NORTHEASTWARD
INTO SOUTHEAST NEB AND EVENTUALLY SOUTHEAST IA THROUGH THE EVENING
HOURS. DO THINK THAT STORMS THAT MOVE INTO THE AREA COULD CARRY A
RISK OF HAIL...AND ALSO WIND...ESPECIALLY AS THEY ORGANIZE INTO A
LINE LATER THIS EVENING AHEAD OF THE FRONT...AS ORIENTATION OF SHEAR
VECTOR IS NEARLY PARALLEL TO FRONTAL FORCING. DO THINK TORNADO
POTENTIAL IS LIMITED BY VEERED SURFACE WIND PROFILE. STORMS SHOULD
PROGRESS ACROSS THE AREA THROUGH THE EVENING HOURS. ECMWF CONTINUES
TO HOLD ONTO A DEFORMATION-ZONE AREA OF RAIN BEHIND THE UPPER-
LOW...WITH A STRONGER LOW THAN NAM/GFS/GEM/UKMET. HELD ONTO A
SHOWER MENTION LATE TONIGHT IN THE SOUTHEAST CWA AS A NOD TO THE
STRONGER ECMWF SOLUTION.
UPPER-LEVEL SYSTEM LACKS ANY KIND OF COLD AIR PUSH BEHIND IT...AND
MILD TEMPERATURES WILL CONTINUE INTO THE WORK WEEK. TEMPS SHOULD
PEAK ON MONDAY UNDER WARM AIR ADVECTION AND LOW-LEVEL
SOUTH/SOUTHWESTERLY FLOW...WITH HIGHS LIKELY TO CRACK 80 IN PARTS OF
EASTERN NEB. A WEAK FRONTAL PASSAGE ASSOCIATED WITH A WEAK UPPER-
LEVEL WAVE WILL SKIRT THROUGH THE AREA ON TUESDAY...BRINGING MAYBE A
FEW EXTRA CLOUDS AND A SLIGHT DIP IN TEMPERATURES TO LESS ABOVE-
NORMAL READINGS.
MAYES
LONG TERM...TUESDAY NIGHT THROUGH SATURDAY
GLOBAL MODELS ARE IN BETTER AGREEMENT TODAY IN THE LARGE SCALE FLOW
ACROSS THE CONUS FOR THE SECOND HALF OF THE WORK WEEK. MOST
OPERATIONAL AND ENSEMBLES MODELS NOW AMPLIFY A STRONG SHORTWAVE
TROUGH DIVING INTO THE CNTRL US ON WED. THIS DRIVES A STRONG COLD
FRONT THROUGH THE FA ON WED. WE WILL CONT WITH THE CHC OF SHOWERS
FOR LATE TUE NIGHT IN THE NORTH...SPREADING ACROSS A GOOD PART OF
OUR FA FOR WED. WE MAY SEE THE SHOWERS SHUT OFF FOR A TIME ON WED
NIGHT AS THE MID LEVEL DRY-SLOT WORKS THROUGH THE FORECAST AREA. BUT
THE WRAP-AROUND/DEFORMATION ZONE LOOKS TO IMPACT AT LEAST OUR
NORTHERN AND ERN FA THU AND THU NIGHT WITH CHC POPS IN THE FORECAST.
IT APPEARS THEN THAT THIS PERIOD OF THE FORECAST WILL SEE WELL BELOW
NORMAL TEMPERATURES FOR HIGHS...ESPECIALLY ON THU WHERE HIGHS MAY
NOT GET OUT OF THE MID 40S WITH BREEZY CONDITIONS. WILL LEAVE THE
LATER HALF OF FRI AND INTO SAT DRY ATTM WITH SOME MODERATION TO
TEMPERATURES.
BOUSTEAD
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
246 AM EDT SUN OCT 14 2012
.SYNOPSIS...
RAIN WILL BE WIDESPREAD ACROSS CENTRAL NEW YORK AND PARTS OF
NORTHEAST PENNSYLVANIA EARLY THIS MORNING AS A WARM FRONT CROSSES
THE REGION. BEHIND THE WARM FRONT, A FEW SHOWERS WILL BE POSSIBLE
SUNDAY MORNING. OTHERWISE, IT WILL BE WARMER WITH HIGHS IN THE 60S
TO LOWER 70S. A COLD FRONT WILL CROSS THE REGION MONDAY, WITH A
CHANCE FOR MORE SHOWERS, ALONG WITH A RETURN TO COOLER WEATHER.
&&
.NEAR TERM /THROUGH TODAY/...
RADARS SHOW RAINS INCREASING ACROSS MUCH OF CENTRAL NEW YORK IN
RESPONSE TO INCREASING ISENTROPIC LIFT AND MOISTURE ADVECTION.
THIS ISEN LIFT/MOISTURE ADVECTION WAS IN ADVANCE OF A SHORT WAVE
RIPPLING THROUGH NORTHERN ONTARIO. THIS FEATURE WAS INCREASING
UPPER CONFLUENCE TO OUR NORTHEAST ENHANCING THE THERMALLY DIRECT
JET STREAK CIRCULATION FOR NY AND PA. THIS WAS ALLOWING FOR THE
STRGR ISEN LIFT AND PRECIPITATION TO BREAK OUT. BY AROUND
9Z...THIS WAVE PASSES AND THE WAA IMPULSE WILL WEAKEN AND THE MORE
WIDESPREAD RAINS WILL TAPER TO SCATTERED SHOWERS/SPRINKLES. THIS
OCCURS AT THE SAME TIME THAT THE STRONGER UPPER LEVEL LOW AND
ASSOCIATED SURFACE CYCLONE IN THE PLAINS INTENSIFIES AND INCREASES
THE DOWNSTREAM RIDGING ALOFT OVER THE EAST. THIS WILL ALLOW THE
WARM FRONT TO EVENTUALLY PUSH NORTH OF THE REGION SUNDAY LATER IN
THE MORNING AS THE ISENTROPES WILL EASILY BE ADVECTED NORTH AND
NOT BE HELD UP BY A JET STREAK AND ASSOCIATED GEOSTROPHIC
ADJUSTMENTS.
LATEST HRRR HAD THE BEST HANDLE ON THE RADAR ECHOES AT THIS TIME IN
OHIO WHICH WAS MUCH FARTHER SOUTH THAN THE NAM...GFS...AND OTHER
CONVECTION ALLOWING HIGH RES MODELS. SINCE THIS MODEL SEEMS TO HAVE
INITIALIZED WELL AND THE PRECIP IS FARTHER S...I WENT ALONG WITH
THE IDEA OF HAVING MORE PRECIP SLIDE ACROSS NRN PA IN LINE WITH
THE LATEST HRRR LATER TONIGHT. I RAISED POPS IN NE PA FOR LATER TONIGHT
AS A RESULT.
FOR SUNDAY...WARM FRONT CLEARS REGION TO THE NORTH. ALL HIGHER
RESOLUTION MODELS PULL PRECIP NORTH OF THE WFO BGM FORECAST AREA
BY ARND 18Z. SO I HAVE SUN PM DRY AND MILD AND CUT BACK ON POPS
FROM PREVIOUS FORECAST. OTHERWISE NO MAJOR CHANGES.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
330 PM UPDATE...
STRONGEST LIFT MOVES NORTHEAST AS A WARM FRONT LIFTS INTO NNY SUNDAY.
WILL DECREASE POPS FROM SOUTHWEST TO NORTHEAST EARLY...AND
MAINTAIN CHANCE POPS THROUGH THE AFTERNOON ONLY ACROSS NORTHERN
ONEIDA COUNTY. WE WILL REMAIN BREEZY THROUGH EARLY
AFTERNOON...AGAIN WITH THE HIGHER WINDS OVER THE HIGHEST TERRAIN.
WE LOOK FAIRLY DRY THROUGH SUNDAY NIGHT WITH POPS INCREASING
TOWARD DAYBREAK MONDAY AS A COLD FRONT ENTERS THE WESTERN PART OF
THE CWA.
NOT OVERLY IMPRESSED WITH THE FRONTAL PASSAGE MONDAY AND WILL KEEP
POPS IN THE CHANCE RANGE. BY AFTERNOON MOST OF THE CWA SHOULD BE
DRY WITH THE EXCEPTION OF THE FAR SOUTHEAST AS SOME MOISTURE MOVES
UP THE COAST. A TROF MOVES THROUGH MONDAY NIGHT WITH A FEW
SHOWERS. WITH 850S IN THE 0C TO -2C RANGE TUESDAY ON A NORTHWEST
FLOW LAKE SHOWERS WILL BE AROUND BUT STRONG NVA ON THE BACKSIDE OF
THE UPPER TROF WILL LIMIT THE POTENTIAL TO JUST SLIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
2 AM UPDATE...
LITTLE CHANGE TO THE LONG TERM GRIDS. HIGH PRESSURE WEDNESDAY THEN
TIMING DIFFERS ON A STACKED LOW AND OCCLUDED FRONT. GFS SAYS
THURSDAY WHILE EURO AND HPC SAY FRIDAY. HAVE LEFT THE POPS CLOSE
TO BEFORE WITH INCREASING POPS FROM WEST TO EAST THU THEN CHC POPS
THU NGT ON. SLOW COOL DOWN FRIDAY TO SUNDAY BUT THE AIR MASS WILL
BE MODERATED AS THE LOW WEAKENS AND LIFTS NORTHEAST INTO SRN
QUEBEC. ALSO CLOUDS WILL AGAIN DOMINATE SO LESS SWING IN TEMPS.
330 PM UPDATE...
MAIN FEATURE OF NOTE TO WATCH DURING THIS EXTENDED PERIOD WILL BE AN
UPPER LEVEL CLOSED LOW MOVING SLOWLY EAST FROM THE MIDWEST. MODEL
TRENDS HAVE BEEN TO SLOW THIS FEATURE DOWN WITH TIME. LATEST GFS AND
12Z ECMWF INDICATE THAT THIS SYSTEM MAY NOT BRING ANY RAIN TO OUR
AREA UNTIL FRIDAY. BASED ON THIS WILL GO WITH A DRY MILD FORECAST
WEDNESDAY THROUGH THURSDAY WITH ABOVE NORMAL HIGHS MAINLY IN THE MID
TO UPPER 60S AND LOWS IN THE 40S TO LOWER 50S. WILL BRING HIGH
CHANCE POPS ACROSS THE AREA FRIDAY AND CONTINUED MILD WITH HIGHS
MAINLY IN THE 60S. THE WEEKEND LOOKS COOLER AND CONTINUED UNSETTLED
WITH A CHANCE OF SHOWERS AS THE CLOSED LOW MOVES EAST ACROSS THE
AREA.
&&
.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
130 AM UPDATE...
GENERAL TREND FROM VFR TO MVFR CIGS AND MAYBE MVFR VSBYS
EARLY THIS MORNING THEN BACK TO VFR BY 16Z. CLOUDS AND LIGHT TO
BRIEF MODERATE RAIN WITH A WARM FRONT LIFTING NORTHEAST THROUGH
THE AREA. KAVP WILL BE OUT OF MOST OF THE RAIN AND SHOULD REMAIN
VFR. NY SITES WILL FALL TO MVFR CIGS BETWEEN 8 AND 10Z THEN RETURN
TO VFR BETWEEN 14 AND 16Z.
IFR CHANCES ARE LOW AND HAVE LEFT OUT. VERY SMALL CHANCES FOR ITH
AND BGM TO FALL BELOW 1K FT CIG. RME A LITTLE BETTER CHANCE OF IFR
CIG BUT WITH A SE FLOW DOWNSLOPED. RME NOW HAS AN IFR VSBY BUT
THAT IS ONLY WITH THE MODERATE RAIN AND WILL NOT LAST LONG.
WINDS SE TO S AT 5 TO 10 KTS EARLY THIS MORNING. SOUTH WINDS
AROUND 10 KTS DURING THE DAY THEN BACK TO SE TO S AT 5 TO 10 KTS
THIS EVENING.
OUTLOOK...
LATE TONIGHT TO TUESDAY...MVFR AND MAYBE IFR MOSTLY LATE AT NIGHT.
SOME SHOWERS WITH A FRONT MONDAY COULD BRING BRIEF MVFR.
WED AND THU...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...HEDEN
LONG TERM...MSE/TAC
AVIATION...TAC
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
1022 AM CDT SUN OCT 14 2012
.DISCUSSION...LOW STRATUS REMAINS ACROSS PORTIONS OF THE DEVILS
LAKE BASIN AND INTO THE NORTHERN VALLEY. PATCHY DENSE FOG REMAINS
ACROSS PORTIONS OF THE DEVILS LAKE BASIN. SURFACE HIGH WILL BE
MOVING INTO THE DEVILS LAKE BASIN THIS AFTERNOON. THUS...LIGHT
WINDS WILL REMAIN THROUGH THE DAY HERE. MID OCTOBER SUN ANGLE
LIKELY NOT ENOUGH TO QUICKLY ERODE THIS CLOUD DECK UNTIL MAYBE
MID-AFTERNOON. USING THE 12Z HRRR AS A GUIDE...WILL UPDATE THIS
AREA TO MOSTLY CLOUDY INTO THE AFTERNOON HOURS. VISIBILITY IN THE
FOG SHOULD IMPROVE BY AFTERNOON. THE CLOUD DECK WILL AFFECT
TEMPS...AND DID NEED TO SIGNIFICANTLY LOWER MAX TEMPS WHERE CLOUDS
ARE EXPECTED TO REMAIN THE LONGEST. CLOUDS ALSO REMAIN ACROSS THE
FAR EASTERN FA...AND MADE SOME MINOR UPDATES HERE AS WELL. THE
SOUTHERN FA NEEDED NO CHANGES.
&&
.AVIATION...BEMIDJI AREA TO BE ON THE EDGE OF THE LOWER CLOUDS
AND FOG PATCHES WHICH PREVAIL JUST TO THE EAST...WHICH SHOULD
CLEAR THIS AFTERNOON. LOWER CLOUDS ALSO AFFECTING THE DEVILS LAKE
BASIN AND NORTHERN VALLEY AREAS...WHICH ARE EXPECTED TO REMAIN
INTO AT LEAST THE EARLY AFTERNOON HOURS. STILL SOME QUESTION
REGARDING WHAT THESE CLOUDS WILL DO.
&&
.PREV DISCUSSION... /ISSUED 853 AM CDT SUN OCT 14 2012/
UPDATE...INSERTED PATCHY DENSE FOG WITHIN THE DEVILS LAKE BASIN
FOR THE REMAINDER OF THE MORNING HOURS. WEB CAMS CONFIRM THE
FOG...AND HRRR INDICATES IT COULD REMAIN FOR A FEW MORE HOURS.
THIS SEEMS REASONABLE GIVEN LIGHT WIND REGIME. FOR NOW...THINKING
FOG/CLOUDS WILL CLEAR BY THE AFTERNOON ALLOWING FOR TEMPS TO RISE
TO NEAR FORECASTED VALUES. WILL TAKE A LOOK AT THE SITUATION AGAIN
IN A COUPLE HOURS.
PREV DISCUSSION... /ISSUED 335 AM CDT SUN OCT 14 2012/
SHORT TERM...
EARLIER COLD FRONT WHICH MOVED THROUGH THE FCST AREA MUCH MORE
ILL-DEFINED FROM NORTHEAST TO SOUTHWESTERN MINNESOTA AS THERE IS
AN AREA OF NORTH WINDS NORTH OF SURFACE LOW IN SOUTHWEST IOWA OVER
THE SOUTHEAST HALF OF MINNESOTA AND AN AREA OF NORTHWEST SFC WINDS
OVER NW MN AND ERN ND BEHIND ACTUAL COLD FRONT. AXIS OF LIGHT
WINDS FROM THE MN ARROWHEAD SOUTHWEST TOWARD ST CLOUD-WILMAR. IN
THIS ZONE THERE IS EXTENSIVE LOW CLOUDS AND FOG. WRN EDGE OF LOW
CLOUDS SKIRTING WADENA-BEMIDJI AREAS AND THIS IS LIKELY TO BE THE
CASE THROUGH THE REST OF THE EARLY MORNING. MOST OF THE FOG SHOULD
STAY EAST OF OUR AREA HOWEVER. OTHERWISE GOT SOME PATCHES OF
HIGH/MID LEVEL CLOUD COVER WITH TEMPS MOSTLY IN THE LOWER-MID 30S.
FOR TODAY...WATER VAPOR SHOWS SEVERAL WEAK SHORT WAVES IN SRN
SASKATCHEWAN WHICH ARE PROGGED TO MOVE EAST-SOUTHEAST THRU THE
AREA. UPSTREAM OBS/SATELLITE SHOWS SOME MID LEVEL CLOUDS. EVEN A
FEW LIGHT -SHRA IN SRN SASK INTO FAR NW ND. DO EXPECT A MIX OF
CLOUD/SUN TODAY WITH A GENERAL LIGHT NORTH- NORTHWEST WIND WITH
TEMPS A FEW DEGREES COOLER TODAY AS 925-850 MB COOL THRU 18Z
BEFORE WARMING A BIT LATE TODAY- TONIGHT. ATTM WILL NOT INCLUDE
ANY PRECIP...BUT NOT IMPOSSIBLE TO HAVE A FEW MID CLOUD SPRINKLES
BASED ON UPSTREAM OBS. LIGHT WINDS TONIGHT SHOULD ALLOW TEMPS TO
FALL OFF PRETTY QUICKLY IN MANY AREAS DESPITE WARMING JUST ABOVE
THE SFC. HOW COOL DEPENDS ON CLOUD COVER AS WILL PROBABLY HAVE
SOME PATCHES OF MID- HIGH CLOUDS AROUND.
MONDAY WILL SEE AN AREA OF THICKER MID LEVEL MOISTURE MOVE THRU
MAINLY IN RESPONSE TO 850 MB WARM ADVECTION. MODELS INSIST ON A
FEW SHOWERS OVER FAR NRN FCST AREA MONDAY LATE MORNING-AFTN SO
WILL CONTINUE TO MENTION. WILL CONTINUE MENTION INTO PARTS OF MON
NIGHT AS WELL OVER NW MN IN 850 MB WARM ADV ZONE. MONDAY HIGH
TEMPS LOOK NOT QUITE AS WARM AS PREVIOUSLY FORECASTED DUE TO CLOUD
COVER. ALL BLEND AND CONSALL TEMPS INDICATE HIGHS UPPER 50S
NORTHEAST TO LOWER 70S SOUTHWEST.
TUESDAY WILL BE GENERALLY DRY AND MILD BUT WILL SEE SOME LATE DAY
CHANCES FOR LIGHT RAIN ENTER THE DVL BASIN IN ADVANCE OF THE
LARGER MID WEEK SYSTEM.
LONG TERM (WEDNESDAY-SATURDAY)...
PACIFIC SHORTWAVE ENERGY IS EXPECTED TO CASCADE SOUTHEASTWARD ACROSS
THE CENTRAL US ON WEDNESDAY....FORMING A DEEP CLOSED LOW BY
WEDNESDAY NIGHT/THURSDAY. THE 00Z GFS IS FARTHEST EAST WITH THE
SYSTEM...WITH THE LOW CENTERED ACROSS WI...WHILE THE 00Z GEM AND
ESPECIALLY THE 00Z ECMWF ARE FARTHER WEST. THE MODELS DO AGREE THAT
A STRONG SFC LOW ASSOCIATED WITH THE UPPER LOW WILL DROP SOUTHEAST
OUT OF SOUTHERN CANADA AND OCCLUDE AS IT EVER SO SLOWLY PUSHES
ACROSS THE UPPER MIDWEST/GREAT LAKES THROUGH THE END OF THE WORK
WEEK. MODELS DIFFER QUITE A BIT ON THE PLACEMENT OF PRECIP WITH THE
SYSTEM...WITH THE FURTHER WEST GEM AND ECMWF SOLUTIONS SUGGESTING A
DECENT RAIN EVENT. HOWEVER...STILL A LOT OF QUESTIONS REGARDING THE
EVOLUTION OF THIS SYSTEM...AND OVERALL CONFIDENCE IN THE PLACEMENT
OF PRECIP IS LOW. NOT A LOT OF COLD AIR IS EXPECTED WITH THIS
SYSTEM...BUT WITH SOME LOW-LEVEL COLD ADVECTION WITH BRISK NORTH
WINDS ON THE BACK-SIDE OF THE LOW...AND EXTENSIVE
CLOUDS/SHOWERS...TEMPS ARE EXPECTED TO COOL DOWN BELOW SEASONAL
AVERAGES FOR THE LATTER HALF OF THE WORK WEEK.
LOW FORECAST CONFIDENCE EXISTS FOR FRIDAY/SATURDAY...WITH THE GFS
MORE PROGRESSIVE IN LIFTING THE UPPER LOW NORTHEASTWARD THAN THE
ECMWF. NEVERTHELESS...A GRADUAL DRYING TREND IS EXPECTED LATE IN THE
PERIOD.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
TG
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
853 AM CDT SUN OCT 14 2012
.UPDATE...INSERTED PATCHY DENSE FOG WITHIN THE DEVILS LAKE BASIN
FOR THE REMAINDER OF THE MORNING HOURS. WEB CAMS CONFIRM THE
FOG...AND HRRR INDICATES IT COULD REMAIN FOR A FEW MORE HOURS.
THIS SEEMS REASONABLE GIVEN LIGHT WIND REGIME. FOR NOW...THINKING
FOG/CLOUDS WILL CLEAR BY THE AFTERNOON ALLOWING FOR TEMPS TO RISE
TO NEAR FORECASTED VALUES. WILL TAKE A LOOK AT THE SITUATION AGAIN
IN A COUPLE HOURS.
&&
.AVIATION...BEMIDJI AREA TO BE ON THE EDGE OF THE LOWER CLOUDS
AND FOG PATCHES WHICH PREVAIL JUST TO THE EAST. SO TAF FCST WILL
HAVE SOME MENTION OF MVFR VSBYS AND PSBL IFR CIGS THROUGH MID TO
LATE MORNING. DENSE FOG NEAR KDVL SHOULD DISSIPATE BY MID TO LATE
MORNING. OTHERWISE VFR TODAY WITH LIGHT NORTH-NORTHWEST WIND AND
SOME MID-HIGH LEVEL CLOUD COVER.
&&
.PREV DISCUSSION... /ISSUED 335 AM CDT SUN OCT 14 2012/
SHORT TERM...
EARLIER COLD FRONT WHICH MOVED THROUGH THE FCST AREA MUCH MORE
ILL-DEFINED FROM NORTHEAST TO SOUTHWESTERN MINNESOTA AS THERE IS
AN AREA OF NORTH WINDS NORTH OF SURFACE LOW IN SOUTHWEST IOWA OVER
THE SOUTHEAST HALF OF MINNESOTA AND AN AREA OF NORTHWEST SFC WINDS
OVER NW MN AND ERN ND BEHIND ACTUAL COLD FRONT. AXIS OF LIGHT
WINDS FROM THE MN ARROWHEAD SOUTHWEST TOWARD ST CLOUD-WILMAR. IN
THIS ZONE THERE IS EXTENSIVE LOW CLOUDS AND FOG. WRN EDGE OF LOW
CLOUDS SKIRTING WADENA-BEMIDJI AREAS AND THIS IS LIKELY TO BE THE
CASE THROUGH THE REST OF THE EARLY MORNING. MOST OF THE FOG SHOULD
STAY EAST OF OUR AREA HOWEVER. OTHERWISE GOT SOME PATCHES OF
HIGH/MID LEVEL CLOUD COVER WITH TEMPS MOSTLY IN THE LOWER-MID 30S.
FOR TODAY...WATER VAPOR SHOWS SEVERAL WEAK SHORT WAVES IN SRN
SASKATCHEWAN WHICH ARE PROGGED TO MOVE EAST-SOUTHEAST THRU THE
AREA. UPSTREAM OBS/SATELLITE SHOWS SOME MID LEVEL CLOUDS. EVEN A
FEW LIGHT -SHRA IN SRN SASK INTO FAR NW ND. DO EXPECT A MIX OF
CLOUD/SUN TODAY WITH A GENERAL LIGHT NORTH- NORTHWEST WIND WITH
TEMPS A FEW DEGREES COOLER TODAY AS 925-850 MB COOL THRU 18Z
BEFORE WARMING A BIT LATE TODAY- TONIGHT. ATTM WILL NOT INCLUDE
ANY PRECIP...BUT NOT IMPOSSIBLE TO HAVE A FEW MID CLOUD SPRINKLES
BASED ON UPSTREAM OBS. LIGHT WINDS TONIGHT SHOULD ALLOW TEMPS TO
FALL OFF PRETTY QUICKLY IN MANY AREAS DESPITE WARMING JUST ABOVE
THE SFC. HOW COOL DEPENDS ON CLOUD COVER AS WILL PROBABLY HAVE
SOME PATCHES OF MID- HIGH CLOUDS AROUND.
MONDAY WILL SEE AN AREA OF THICKER MID LEVEL MOISTURE MOVE THRU
MAINLY IN RESPONSE TO 850 MB WARM ADVECTION. MODELS INSIST ON A
FEW SHOWERS OVER FAR NRN FCST AREA MONDAY LATE MORNING-AFTN SO
WILL CONTINUE TO MENTION. WILL CONTINUE MENTION INTO PARTS OF MON
NIGHT AS WELL OVER NW MN IN 850 MB WARM ADV ZONE. MONDAY HIGH
TEMPS LOOK NOT QUITE AS WARM AS PREVIOUSLY FORECASTED DUE TO CLOUD
COVER. ALL BLEND AND CONSALL TEMPS INDICATE HIGHS UPPER 50S
NORTHEAST TO LOWER 70S SOUTHWEST.
TUESDAY WILL BE GENERALLY DRY AND MILD BUT WILL SEE SOME LATE DAY
CHANCES FOR LIGHT RAIN ENTER THE DVL BASIN IN ADVANCE OF THE
LARGER MID WEEK SYSTEM.
LONG TERM (WEDNESDAY-SATURDAY)...
PACIFIC SHORTWAVE ENERGY IS EXPECTED TO CASCADE SOUTHEASTWARD ACROSS
THE CENTRAL US ON WEDNESDAY....FORMING A DEEP CLOSED LOW BY
WEDNESDAY NIGHT/THURSDAY. THE 00Z GFS IS FARTHEST EAST WITH THE
SYSTEM...WITH THE LOW CENTERED ACROSS WI...WHILE THE 00Z GEM AND
ESPECIALLY THE 00Z ECMWF ARE FARTHER WEST. THE MODELS DO AGREE THAT
A STRONG SFC LOW ASSOCIATED WITH THE UPPER LOW WILL DROP SOUTHEAST
OUT OF SOUTHERN CANADA AND OCCLUDE AS IT EVER SO SLOWLY PUSHES
ACROSS THE UPPER MIDWEST/GREAT LAKES THROUGH THE END OF THE WORK
WEEK. MODELS DIFFER QUITE A BIT ON THE PLACEMENT OF PRECIP WITH THE
SYSTEM...WITH THE FURTHER WEST GEM AND ECMWF SOLUTIONS SUGGESTING A
DECENT RAIN EVENT. HOWEVER...STILL A LOT OF QUESTIONS REGARDING THE
EVOLUTION OF THIS SYSTEM...AND OVERALL CONFIDENCE IN THE PLACEMENT
OF PRECIP IS LOW. NOT A LOT OF COLD AIR IS EXPECTED WITH THIS
SYSTEM...BUT WITH SOME LOW-LEVEL COLD ADVECTION WITH BRISK NORTH
WINDS ON THE BACK-SIDE OF THE LOW...AND EXTENSIVE
CLOUDS/SHOWERS...TEMPS ARE EXPECTED TO COOL DOWN BELOW SEASONAL
AVERAGES FOR THE LATTER HALF OF THE WORK WEEK.
LOW FORECAST CONFIDENCE EXISTS FOR FRIDAY/SATURDAY...WITH THE GFS
MORE PROGRESSIVE IN LIFTING THE UPPER LOW NORTHEASTWARD THAN THE
ECMWF. NEVERTHELESS...A GRADUAL DRYING TREND IS EXPECTED LATE IN THE
PERIOD.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
TG
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1104 AM EDT SUN OCT 14 2012
.SYNOPSIS...
A LOW PRESSURE SYSTEM LIFTING OUT OF THE PLAINS WILL TRAVEL NORTHEAST
INTO MICHIGAN. A STONG COLD FRONT EXTENDING SOUTH OF THE LOW WILL
PUSH ACROSS THE REGION...BRINGING STRONG WINDS AND THE CHANCE FOR
SEVERE THUNDERSTORMS LATE THIS AFTERNOON INTO TONIGHT. HIGH
PRESSURE AND DRIER AIR WILL ARRIVE BY LATE MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ADJUSTED TIMING OF PRECIP ONSET AS WELL AS CONVECTION. CURRENTLY
DIMINISHING OF SHOWERS OVER INDIANA SO HAVE DELAYED ONSET OF SCT
SHOWERS...AND WHILE THUNDERSTORMS POSSIBLE THIS AFTERNOON...SHOULD
BE MAINLY SHRA WITH ISOLATED TSTMS WITH SOME CONVECTIVE INHIBITION
EARLY. CAPE VALUES STILL NOT TERRIBLY IMPRESSIVE BUT ENOUGH TO
SPARK TSTMS ESPECIALLY NR/AFTER 20Z...WITH LATEST RAP PEAKING OUT AT
600 J/KG OVER INDIANA...AND THEN DIMINISHING SIGNIFICANTLY OVER
AREA BY 00Z-02Z. BEST SEVERE CHANCE WILL BE WITH STORMS THAT
DEVELOP AS CAPE STILL DECENT IN THE SW WHILE LL WIND FIELD STILL
IMPRESSIVE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
CDFNT WONT SWING THROUGH UNTIL AFTER 00Z TONIGHT. EXPECT A SECOND
LINE OF CONVECTION TO DEVELOP JUST AHEAD OF THE FRONT. NOT SURE IF
THIS SECOND LINE WILL BE SEVERE...DUE TO THE TIMING WHICH IS AFTER
SUNSET. WILL CARRY CATEGORICAL POPS BEFORE 06Z WITH EXPECTED
CONVECTION AHEAD OF THE FRONT.
COOLER AIR WILL BEGIN TO WORK IN BEHIND THE FRONT AFTER 06Z. ON
MONDAY...A DEEP H5 TROF WILL SWING ACROSS THE REGION. NW CAA WILL
COMBINE WITH THE LIFT FROM THE TROF TO KICK OFF SOME SCT SHRA.
BEST CHC WILL BE ACROSS THE N...BUT DID TAKE SLGT CHC POPS DOWN TO
THE OHIO RIVER.
SKIES WILL CLEAR QUICKLY MONDAY NIGHT AS A HIGH PRESSURE RIDGE
BUILDS IN FROM THE W. THE SFC RIDGE WILL PROVIDE DRY WEATHER ON
TUESDAY...BUT ZONAL FLOW AT H5 WILL ALLOW UPPER LEVEL MOISTURE TO
SPILL SOME CLOUDS INTO THE REGION.
DROPPED TEMPERATURES DOWN INTO THE UPPER 40S IN THE NW AND LOWER
50S ELSEWHERE FOR TONIGHT. THEN ON MONDAY...THE COOL NW FLOW WILL
HOLD TEMPERATURES DOWN INTO THE MID 50S ACROSS THE NW AND THE
LOWER 60S IN THE EXTREME S. CLEAR SKIES AND LIGHT WINDS WILL ALLOW
TEMPERATURES TO FALL INTO THE UPPER 30S MONDAY NIGHT...BUT
TEMPERATURES SHOULD REBOUND INTO THE 60S FOR TUESDAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
UPPER LEVEL FLOW PATTERN TO UNDERGO A TRANSITION WITH ENERGY FROM
THE PACIFIC NORTHWEST CARVING OUT A DEEP UPPER LOW OVER THE
NATIONS MID SECTION. WILL INTRODUCE CHC POPS INTO THE FAR WEST
WEDNESDAY NIGHT AHD OF AN APPROACHING FRONT. EXPECT ABOVE NORMAL
TEMPERATURES WEDNESDAY WITH HIGHS RANGING FROM THE UPPER 60S NORTH
TO THE LOWER 70S SOUTH.
WITH THE UPPER LOW DEEPENING AND SETTLING INTO THE UPPER MS VLY AN
OCCLUDED FRONT TO PUSH THRU OHIO THURSDAY NIGHT/EARLY FRIDAY. SOME
TIMING DIFFERENCES EXIST...SO WILL INCREASE POPS TO HIGH CHC
CATEGORY. TEMPS TO CONT TO BE ABOVE NORMAL ON THURSDAY WITH HIGHS
FROM THE LOWER 60S NORTHWEST TO UPPER 60S SE.
TIMING DIFFERENCES EXIST REGARDING THE PROGRESSION OF THE UPPER LOW
WITH THE ECMWF DEEPER AND SLOWER WITH THIS FEATURE SETTLING INTO THE
OHIO VALLEY AT THE END OF NEXT WEEK. GFS SOLN KEEPS THE UPPER LOW
FURTHER NORTH AND IS QUICKER OPENING UP THE LOW.
WILL TREND POPS LOWER INTO SLIGHT CHC CATEGORY FRIDAY INTO FRIDAY
NIGHT AND THEN BUMP BACK TO CHANCE SATURDAY WITH THE EFFECTS OF THE
UPPER LOW EXPECTED. TEMPERATURES TO TREND COLDER WITH HIGHS ON
FRIDAY RANGING FROM THE UPPER 50S NW TO THE MID 60S SE AND FROM THE
MID 50S NW TO NEAR 60 SE ON SATURDAY.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
PRIMARILY VFR CIGS WILL BE FOUND UNTIL SHOWERS COME IN AFTER ABOUT
18Z AND SPREAD EASTWARD FROM THE IN/OH LINE. OCCASIONAL MVFR
2500-3KFT CIGS MAY POP UP IN AN OBSERVATION OR TWO BUT ARE NOT
EXPECTED TO BE THE RULE UNTIL SHOWERS DEVELOP LATER.
SHOWERS IN THE AFTERNOON WILL GIVE WAY TO THUNDERSTORMS AFTER
ABOUT 20-22Z. A LINE OF CONVECTION IS MORE LIKELY TO BE THE
WEATHER MAKER EARLY THIS EVENING. UNTIL THIS COMES
THROUGH...SOUTHERLY WINDS WILL SEE GUSTS TOPPING 35KT AT TIMES IN
ANY LOCATION AFTER ABOUT 16Z. AFTER THE LINE OF STORMS COMES
THROUGH...WINDS WILL TURN MORE WESTERLY OVERNIGHT AND LOSE A GOOD
BIT OF THEIR KICK BUT STILL BE IN THE UNUSUALLY HIGH 15KT WITH
STRONGER GUSTS DURING THE OVERNIGHT HOURS.
LOWER MVFR CIGS POTENTIALLY DIPPING TO IFR WILL OCCUR IN THE POST-
FRONTAL AIRMASS UNDER THE COLD ADVECTION. DO NOT EXPECT ANY VSBY
RESTRICTIONS IN THESE LOWER CIGS.
.OUTLOOK...MVFR CEILINGS LIKELY SUNDAY NIGHT INTO MONDAY. MVFR
CEILINGS AND VISIBILITIES POSSIBLE THURSDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...WIND ADVISORY UNTIL 8 PM EDT THIS EVENING FOR OHZ026-034-035-
042>046-051>056-060>065-070>074-077>082-088.
KY...WIND ADVISORY UNTIL 8 PM EDT THIS EVENING FOR KYZ089>100.
IN...WIND ADVISORY UNTIL 8 PM EDT THIS EVENING FOR INZ050-058-059-
066-073>075-080.
&&
$$
SYNOPSIS...JDR/SITES
NEAR TERM...JDR
SHORT TERM...SITES
LONG TERM...AR
AVIATION...JDR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1125 PM EDT MON OCT 15 2012
.SYNOPSIS...
A COLD FRONT OVER FAR EASTERN PENNSYLVANIA THIS EVENING WILL EXIT
OFF THE MID ATLANTIC COAST OVERNIGHT. MAINLY DRY AND MILD WEATHER
WILL FOLLOW FOR THE MID-WEEK PERIOD. A DEEP UPPER LEVEL LOW WILL
DEVELOP OVER THE UPPER PLAINS AND MIDWEST OVER THE NEXT FEW DAYS.
THE DEEP LOW WILL THEN MOVE TO THE EAST AND PUSH A COLD FRONT
THROUGH LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
SFC COLD FRONT IS APPROACHING THE NEW JERSEY COAST...AND NW FLOW
IN THE LOWEST 5-6 KFT HAS SPREAD ACROSS ALL OF THE CWA IN ITS
WAKE. STRONG BACKING TO THE FLOW WAS SEEN ACROSS THE EASTERN
2/3RDS OF THE CWA /IN THE MID AND UPPER LEVELS/ AS A SHARPENING
UPPER TROUGH DRIFTS RIGHT OVERHEAD LATE TONIGHT.
LAST VESTIGES OF RAIN WAS BRUSHING SERN YORK AND LANCASTER
COUNTIES ATTM...IN ASSOCIATION WITH UVVEL BENEATH THE FAVORABLE
RIGHT ENTRANCE REGION OF STRONG UPPER JET. SOME PARTIAL CLEARING
WILL OCCUR ACROSS THE SUSQ VALLEY THANKS TO DEEPENING SUBSIDENCE
AS THE LEFT ENTRANCE REGION OF THE 115 KT UPPER JET DRAGS ACROSS
THAT REGION.
FURTHER WEST...STRONG MID LEVEL /700-500MB/ COLD ADVECTION AND A
POCKET OF STEEP 850-700 MB LAPSE RATES WAS SUPPORTING SCATTERED
LIGHT SHOWERS ACROSS THE WESTERN MTNS AND LAUREL HIGHLANDS.
LATEST HRRR GUIDANCE SHOWS THIS AREA OF SHOWERS DISSOLVING QUICKLY
OVER THE NEXT FW HOURS AND BECOMING CONFINED TO THE FAR NW ZONES
THROUGH ABOUT 06-07Z.
ADDITONAL RAINFALL AMOUNTS IN ANY OF THESE AFOREMENTIONED AREAS OF
SHOWERS WILL BE 0.05 OR LESS.
THIS POCKET OF COLD AIR ALOFT WITH 700 MB TEMPS INITIALLY AROUND
-8C EARLY THIS EVENING...WILL GRADUALLY FILL/WARM BY 3-4C AS IT
CROSSES CENTRAL PENN...AND REACHES THE SUSQ VALLEY LATE TONIGHT.
OTHERWISE...SHALLOW MOISTURE TRAPPED BENEATH THE LOWERING
SUBSIDENCE INVERSION BASE WILL KEEP SKIES MOSTLY CLOUDY TO CLOUDY
ACROSS THE NRN AND WRN MTNS...WITH VARYING AMOUNTS OF STRATO CU
ACROSS THE SE HALF OF THE FCST AREA.
TEMPS ON TRACK TO ACHIEVE LOWS RIGHT AROUND NORMAL EARLY TUESDAY...
RANGING FROM THE M-U30S ACROSS THE NW...TO THE M40S IN THE SE.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
ANY ISOLD SHRA IN THE NW SHOULD BE DONE AROUND SUNRISE TUES...SO
WILL KEEP POPS NIL AREAWIDE FOR THE DAYTIME. DAYTIME TEMPS WILL
REMAIN VERY CLOSE TO SEASONAL NORMALS...TOPPING OUT IN THE M50S-
M60S. RIDGE AXIS STILL OFF TO THE WEST IN THE MORNING...BUT
OVERHEAD LATE IN THE DAY...SO WINDS SHOULD BEGIN 8-10KTS AND COULD
INCREASE/GUST A LITTLE BUT THEN LIGHTEN UP - ESP IN THE W -
THROUGH THE AFTN. AN UNEVENTFUL BUT TYPICAL AUTUMN DAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
SFC HIGH PRESSURE RIDGE OVER THE REGION FOR MIDWEEK WITH WESTERLY
FLOW TURNING SW ALOFT AHEAD OF DEVELOPING TROUGH. SO DRY WEATHER
WILL PREVAIL TUE NIGHT INTO THU. CHILLY NIGHT TUE NIGHT WITH LOWS IN
THE 30S...BUT RETURN FLOW ON BACK SIDE OF HIGH WILL PUSH TEMPS
SLIGHTLY ABOVE NORMAL ON WED. MILDER NIGHT WED NIGHT...THEN
INCREASING CLOUD COVER WILL BRING SEASONAL TEMPS FOR THU.
TROUGH EDGES TOWARD PA LATE WEEK...WITH FRONT RUNNING OUT AHEAD OF
SYSTEM FOR THU NIGHT/FRI BRINGING BEST CHANCE FOR WIDESPREAD RAIN
THIS WEEK. EASTERN SECTIONS COULD SEE HIGHEST AMOUNTS...WITH QPF
AROUND 0.25 INCHES...POSS UP TO 0.75 INCHES ON EASTERN EDGE.
UNFORTUNATELY...MODELS REMAIN STEADFAST IN THEIR DIFFERENCES THIS
WEEKEND WITH GFS REMAINING WEAKER AND MORE PROGRESSIVE WHILE THE
ECMWF STICKS WITH A LARGER AND SLOWER MOVING LOW. SO FORECAST
CONTINUES TO TRY TO MITIGATE THESE DIFFERENCES INTO A COMPROMISE
SOLUTION. AFTER BEST RAIN CHANCES CENTERED ON FRIDAY...KEPT SCT
SHOWERS POSS INTO THE WEEKEND WITH DRYING TREND LATE. TEMPS DO
COOL OFF A BIT OVER THE WEEKEND INTO EARLY NEXT WEEK...BUT REMAIN
CLOSE TO SEASONAL AVERAGES.
&&
.AVIATION /04Z TUESDAY THROUGH SATURDAY/...
COLD FRONT HAS PUSHED EAST OF THE REGION LATE THIS EVENING AND
DOWNSLOPING WESTERLY FLOW IN IT/S WAKE IS PRODUCING PARTIAL CLEARING
ACROSS THE SUSQ VALLEY. RESIDUAL LOW LVL MOISTURE ASCENDING THE W
MTNS WILL PRODUCE PERSISTENT MVFR STRATO-CU AT BFD AND JST
OVERNIGHT WITH SREF DATA EVEN SUGGESTING THE POSSIBILITY OF CIGS
DIPPING TO IFR LATE TONIGHT.
WHERE SKIES REMAIN CLOUDY...ATMOS WILL REMAIN WELL MIXED AND FAVOR
FREQUENT WIND GUSTS TO NR 20KTS OVERNIGHT ACROSS THE W MTNS.
DOWNSLOPING FLOW EAST OF THE MTNS WILL RESULT IN BRKS IN THE
OVERCAST...SOME RAD COOLING AND LIGHTER WIND SPEEDS.
SOME EARLY LOW CIGS ARE POSSIBLE TO START TUESDAY AT JST OR BFD.
HOWEVER...HIGH PRES BUILDING INTO THE STATE SUPPORTS A HIGH
CONFIDENCE FCST OF VFR CONDS EVERYWHERE BY MIDDAY.
OUTLOOK...
WED...NO SIG WX EXPECTED.
THU...AM LOW CIGS POSSIBLE EAST. PM SHRA/LOW CIGS POSS...MAINLY BFD.
FRI...SHRA/LOW CIGS POSSIBLE...ESP EARLY.
SAT...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...DANGELO
LONG TERM...RXR
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
948 PM EDT MON OCT 15 2012
.SYNOPSIS...
A COLD FRONT OVER FAR EASTERN PENNSYLVANIA THIS EVENING WILL EXIT
OFF THE MID ATLANTIC COAST OVERNIGHT. MAINLY DRY AND MILD WEATHER
WILL FOLLOW FOR THE MID-WEEK PERIOD. A DEEP UPPER LEVEL LOW WILL
DEVELOP OVER THE UPPER PLAINS AND MIDWEST OVER THE NEXT FEW DAYS.
THE DEEP LOW WILL THEN MOVE TO THE EAST AND PUSH A COLD FRONT
THROUGH LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
SFC COLD FRONT IS APPROACHING THE NEW JERSEY COAST...AND NW FLOW
IN THE LOWEST 5-6 KFT HAS SPREAD ACROSS ALL OF THE CWA IN ITS
WAKE. STRONG BACKING TO THE FLOW WAS SEEN ACROSS THE EASTERN
2/3RDS OF THE CWA /IN THE MID AND UPPER LEVELS/ AS A SHARPENING
UPPER TROUGH DRIFTS RIGHT OVERHEAD LATE TONIGHT.
LAST VESTIGES OF RAIN WAS BRUSHING SERN YORK AND LANCASTER
COUNTIES ATTM...IN ASSOCIATION WITH UVVEL BENEATH THE FAVORABLE
RIGHT ENTRANCE REGION OF STRONG UPPER JET. SOME PARTIAL CLEARING
WILL OCCUR ACROSS THE SUSQ VALLEY THANKS TO DEEPENING SUBSIDENCE
AS THE LEFT ENTRANCE REGION OF THE 115 KT UPPER JET DRAGS ACROSS
THAT REGION.
FURTHER WEST...STRONG MID LEVEL /700-500MB/ COLD ADVECTION AND A
POCKET OF STEEP 850-700 MB LAPSE RATES WAS SUPPORTING SCATTERED
LIGHT SHOWERS ACROSS THE WESTERN MTNS AND LAUREL HIGHLANDS.
LATEST HRRR GUIDANCE SHOWS THIS AREA OF SHOWERS DISSOLVING QUICKLY
OVER THE NEXT FW HOURS AND BECOMING CONFINED TO THE FAR NW ZONES
THROUGH ABOUT 06-07Z.
ADDITONAL RAINFALL AMOUNTS IN ANY OF THESE AFOREMENTIONED AREAS OF
SHOWERS WILL BE 0.05 OR LESS.
THIS POCKET OF COLD AIR ALOFT WITH 700 MB TEMPS INITIALLY AROUND
-8C EARLY THIS EVENING...WILL GRADUALLY FILL/WARM BY 3-4C AS IT
CROSSES CENTRAL PENN...AND REACHES THE SUSQ VALLEY LATE TONIGHT.
OTHERWISE...SHALLOW MOISTURE TRAPPED BENEATH THE LOWERING
SUBSIDENCE INVERSION BASE WILL KEEP SKIES MOSTLY CLOUDY TO CLOUDY
ACROSS THE NRN AND WRN MTNS...WITH VARYING AMOUNTS OF STRATO CU
ACROSS THE SE HALF OF THE FCST AREA.
TEMPS ON TRACK TO ACHIEVE LOWS RIGHT AROUND NORMAL EARLY TUESDAY...
RANGING FROM THE M-U30S ACROSS THE NW...TO THE M40S IN THE SE.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
ANY ISOLD SHRA IN THE NW SHOULD BE DONE AROUND SUNRISE TUES...SO
WILL KEEP POPS NIL AREAWIDE FOR THE DAYTIME. DAYTIME TEMPS WILL
REMAIN VERY CLOSE TO SEASONAL NORMALS...TOPPING OUT IN THE M50S-
M60S. RIDGE AXIS STILL OFF TO THE WEST IN THE MORNING...BUT
OVERHEAD LATE IN THE DAY...SO WINDS SHOULD BEGIN 8-10KTS AND COULD
INCREASE/GUST A LITTLE BUT THEN LIGHTEN UP - ESP IN THE W -
THROUGH THE AFTN. AN UNEVENTFUL BUT TYPICAL AUTUMN DAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
SFC HIGH PRESSURE RIDGE OVER THE REGION FOR MIDWEEK WITH WESTERLY
FLOW TURNING SW ALOFT AHEAD OF DEVELOPING TROUGH. SO DRY WEATHER
WILL PREVAIL TUE NIGHT INTO THU. CHILLY NIGHT TUE NIGHT WITH LOWS IN
THE 30S...BUT RETURN FLOW ON BACK SIDE OF HIGH WILL PUSH TEMPS
SLIGHTLY ABOVE NORMAL ON WED. MILDER NIGHT WED NIGHT...THEN
INCREASING CLOUD COVER WILL BRING SEASONAL TEMPS FOR THU.
TROUGH EDGES TOWARD PA LATE WEEK...WITH FRONT RUNNING OUT AHEAD OF
SYSTEM FOR THU NIGHT/FRI BRINGING BEST CHANCE FOR WIDESPREAD RAIN
THIS WEEK. EASTERN SECTIONS COULD SEE HIGHEST AMOUNTS...WITH QPF
AROUND 0.25 INCHES...POSS UP TO 0.75 INCHES ON EASTERN EDGE.
UNFORTUNATELY...MODELS REMAIN STEADFAST IN THEIR DIFFERENCES THIS
WEEKEND WITH GFS REMAINING WEAKER AND MORE PROGRESSIVE WHILE THE
ECMWF STICKS WITH A LARGER AND SLOWER MOVING LOW. SO FORECAST
CONTINUES TO TRY TO MITIGATE THESE DIFFERENCES INTO A COMPROMISE
SOLUTION. AFTER BEST RAIN CHANCES CENTERED ON FRIDAY...KEPT SCT
SHOWERS POSS INTO THE WEEKEND WITH DRYING TREND LATE. TEMPS DO
COOL OFF A BIT OVER THE WEEKEND INTO EARLY NEXT WEEK...BUT REMAIN
CLOSE TO SEASONAL AVERAGES.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
COLD FRONT HAS PUSHED EAST OF THE REGION THIS EVENING AND
DOWNSLOPING WESTERLY FLOW IN IT/S WAKE IS PRODUCING CLEARING SKIES
ACROSS PORTIONS OF THE SUSQ VALLEY. RESIDUAL LOW LVL MOISTURE
ASCENDING THE W MTNS WILL PRODUCE PERSISTENT MVFR STRATO-CU AT
BFD AND JST OVERNIGHT WITH SREF DATA EVEN SUGGESTING THE POSSIBILITY
OF CIGS DIPPING TO IFR LATE TONIGHT. A FEW SHRA NOTED ON RADAR
ACROSS WESTERN PA AT 23Z ASSOC WITH APPROACH OF UPPER LVL TROUGH.
THESE SHRA SHOULD BE CONFINED MAINLY THE W MTNS AND LAST ONLY
UNTIL PASSAGE OF UPPER TROUGH ARND 02Z.
WHERE SKIES REMAIN CLOUDY...ATMOS WILL REMAIN WELL MIXED AND FAVOR
FREQUENT WIND GUSTS TO NR 20KTS OVERNIGHT ACROSS THE W MTNS.
DOWNSLOPING FLOW EAST OF THE MTNS WILL RESULT IN BRKS IN THE
OVERCAST...SOME RAD COOLING AND LIGHTER WIND SPEEDS.
SOME EARLY LOW CIGS ARE POSSIBLE TO START TUESDAY AT JST OR BFD.
HOWEVER...HIGH PRES BUILDING INTO THE STATE SUPPORTS A HIGH
CONFIDENCE FCST OF VFR CONDS EVERYWHERE BY MIDDAY.
OUTLOOK...
WED...NO SIG WX EXPECTED.
THU...AM LOW CIGS POSSIBLE EAST. PM SHRA/LOW CIGS POSS...MAINLY BFD.
FRI...SHRA/LOW CIGS POSSIBLE...ESP EARLY.
SAT...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...DANGELO
LONG TERM...RXR
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
749 PM EDT MON OCT 15 2012
.SYNOPSIS...
A COLD FRONT OVER FAR EASTERN PENNSYLVANIA THIS EVENING WILL EXIT
OFF THE MID ATLANTIC COAST OVERNIGHT. MAINLY DRY AND MILD WEATHER
WILL FOLLOW FOR THE MID-WEEK PERIOD. A DEEP UPPER LEVEL LOW WILL
DEVELOP OVER THE UPPER PLAINS AND MIDWEST OVER THE NEXT FEW DAYS.
THE DEEP LOW WILL THEN MOVE TO THE EAST AND PUSH A COLD FRONT
THROUGH LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
SFC COLD FRONT IS CURRENTLY APPROACHING THE DELAWARE VALLEY AND
WILL MOVE OFF THE MID ATLANTIC COAST OVERNIGHT. STRATIFORM RAIN
HAS EXITED OUR FAR SERN ZONES...FOLLOWED BY SOME PARTIAL CLEARING
AS LLVL DOWNSLOPE WESTERLY FLOW KICKS IN ACROSS THE CENTRAL MTS
AND SUSQ VALLEY THIS EVENING...AND THE DEEPER LIFT ALOFT WANES
AS THE LEFT ENTRANCE REGION OF A NORTH/SOUTH 115 KT UPPER JET
DRAGS ACROSS CENTRAL PENN AND THE SUSQUEHANNA REGION.
FURTHER WEST...STRONG MID LEVEL /700-500MB/ COLD ADVECTION AND A
POCKET OF STEEP 850-700 MB LAPSE RATES WAS SUPPORTING AN AREA OF
LIGHT TO MODERATE RAIN SHOWERS MOVING ACROSS THE WEST CENTRAL MTNS
AND LAUREL HIGHLANDS. LATEST HRRR GUIDANCE SHOWS THIS AREA OF
SHOWERS DWINDLING AS IT MOVES EAST OF THE ALLEGHENY FRONT BETWEEN
23-01Z.
RAINFALL AMOUNTS ACROSS THE SW 1/4 OF THE CWA WILL RANGE FROM JUST
A FEW HUNDREDTHS...TO AROUND 0NE TENTH OF AN INCH IN SOME SPOTS.
THIS POCKET OF COLD AIR ALOFT WITH 700 MB TEMPS INITIALLY AROUND
-8C EARLY THIS EVENING...WILL GRADUALLY FILL/WARM BY 3-4C AS IT
CROSSES CENTRAL PENN...AND REACHES THE SUSQ VALLEY LATE TONIGHT.
A FEW BRIEF SHOWERS ARE POSSIBLE THROUGH EARLY TONIGHT ACROSS THE
CENTRAL RIDGE AND VALLEY REGION /MORE LIKELY SPRINKLES/...BUT MOST
LOCATIONS WILL NOT SEE ENOUGH RAIN TO WET THE GROUND.
GUSTY WEST WINDS ACROSS THE CENTRAL AND WESTERN ZONES
AT DUSK WILL SLACKEN OFF BY MIDNIGHT...BUT THEY WON/T GO CALM
OVERNIGHT CONSIDERING THAT THE RIDGE AXIS IS STILL SEVERAL HUNDRED
MILES OFF TO THE WEST.
THE MOISTURE LAYER BECOMES THINNER AS SUBSIDENCE INCREASES AND
UPPER HEIGHTS RISE LATE TONIGHT....AND PRACTICALLY ALL OF THE
SHOWERS WILL HAVE ENDED BY 07-09Z TUESDAY /EXCEPT FOR THE
LINGERING LAKE EFFECT VARIETY NEAR AND TO THE WEST OF KBFD/.
LOWS TONIGHT WILL BE RIGHT AROUND NORMAL WITH M-U30S ACROSS THE NW
AND M40S IN THE SE.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
ANY ISOLD SHRA IN THE NW SHOULD BE DONE AROUND SUNRISE TUES...SO
WILL KEEP POPS NIL AREAWIDE FOR THE DAYTIME. DAYTIME TEMPS WILL
REMAIN VERY CLOSE TO SEASONAL NORMALS...TOPPING OUT IN THE M50S-
M60S. RIDGE AXIS STILL OFF TO THE WEST IN THE MORNING...BUT
OVERHEAD LATE IN THE DAY...SO WINDS SHOULD BEGIN 8-10KTS AND COULD
INCREASE/GUST A LITTLE BUT THEN LIGHTEN UP - ESP IN THE W -
THROUGH THE AFTN. AN UNEVENTFUL BUT TYPICAL AUTUMN DAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
SFC HIGH PRESSURE RIDGE OVER THE REGION FOR MIDWEEK WITH WESTERLY
FLOW TURNING SW ALOFT AHEAD OF DEVELOPING TROUGH. SO DRY WEATHER
WILL PREVAIL TUE NIGHT INTO THU. CHILLY NIGHT TUE NIGHT WITH LOWS IN
THE 30S...BUT RETURN FLOW ON BACK SIDE OF HIGH WILL PUSH TEMPS
SLIGHTLY ABOVE NORMAL ON WED. MILDER NIGHT WED NIGHT...THEN
INCREASING CLOUD COVER WILL BRING SEASONAL TEMPS FOR THU.
TROUGH EDGES TOWARD PA LATE WEEK...WITH FRONT RUNNING OUT AHEAD OF
SYSTEM FOR THU NIGHT/FRI BRINGING BEST CHANCE FOR WIDESPREAD RAIN
THIS WEEK. EASTERN SECTIONS COULD SEE HIGHEST AMOUNTS...WITH QPF
AROUND 0.25 INCHES...POSS UP TO 0.75 INCHES ON EASTERN EDGE.
UNFORTUNATELY...MODELS REMAIN STEADFAST IN THEIR DIFFERENCES THIS
WEEKEND WITH GFS REMAINING WEAKER AND MORE PROGRESSIVE WHILE THE
ECMWF STICKS WITH A LARGER AND SLOWER MOVING LOW. SO FORECAST
CONTINUES TO TRY TO MITIGATE THESE DIFFERENCES INTO A COMPROMISE
SOLUTION. AFTER BEST RAIN CHANCES CENTERED ON FRIDAY...KEPT SCT
SHOWERS POSS INTO THE WEEKEND WITH DRYING TREND LATE. TEMPS DO
COOL OFF A BIT OVER THE WEEKEND INTO EARLY NEXT WEEK...BUT REMAIN
CLOSE TO SEASONAL AVERAGES.
&&
.AVIATION /23Z MONDAY THROUGH SATURDAY/...
COLD FRONT HAS PUSHED EAST OF THE REGION THIS EVENING AND
DOWNSLOPING WESTERLY FLOW IN IT/S WAKE IS PRODUCING CLEARING SKIES
ACROSS PORTIONS OF THE SUSQ VALLEY. RESIDUAL LOW LVL MOISTURE
ASCENDING THE W MTNS WILL PRODUCE PERSISTENT MVFR STRATO-CU AT
BFD AND JST OVERNIGHT WITH SREF DATA EVEN SUGGESTING THE POSSIBILITY
OF CIGS DIPPING TO IFR LATE TONIGHT. A FEW SHRA NOTED ON RADAR
ACROSS WESTERN PA AT 23Z ASSOC WITH APPROACH OF UPPER LVL TROUGH.
THESE SHRA SHOULD BE CONFINED MAINLY THE W MTNS AND LAST ONLY
UNTIL PASSAGE OF UPPER TROUGH ARND 02Z.
WHERE SKIES REMAIN CLOUDY...ATMOS WILL REMAIN WELL MIXED AND FAVOR
FREQUENT WIND GUSTS TO NR 20KTS OVERNIGHT ACROSS THE W MTNS.
DOWNSLOPING FLOW EAST OF THE MTNS WILL RESULT IN BRKS IN THE
OVERCAST...SOME RAD COOLING AND LIGHTER WIND SPEEDS.
SOME EARLY LOW CIGS ARE POSSIBLE TO START TUESDAY AT JST OR BFD.
HOWEVER...HIGH PRES BUILDING INTO THE STATE SUPPORTS A HIGH
CONFIDENCE FCST OF VFR CONDS EVERYWHERE BY MIDDAY.
OUTLOOK...
WED...NO SIG WX EXPECTED.
THU...AM LOW CIGS POSSIBLE EAST. PM SHRA/LOW CIGS POSS...MAINLY BFD.
FRI...SHRA/LOW CIGS POSSIBLE...ESP EARLY.
SAT...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...DANGELO
LONG TERM...RXR
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1205 AM CDT SUN OCT 14 2012
.DISCUSSION...
SEE 06Z AVIATION DISCUSSION...
&&
.AVIATION...
ISOLATED STREAMER SHOWERS MOVING ON SHORE FROM THE GULF MAY
CONTRIBUTE TO OCCASIONAL MVFR CIGS AT GLS OVER NIGHT. WIDELY
SCATTERED SHOWERS ARE ALSO DEVELOPING TO THE WEST OF CLL. THIS
ACTIVITY SHOULD MOVE IN TO CLL VICINITY AFTER 08Z. TERMINALS WEST
OF HOUSTON METRO AREA WILL LIKELY HAVE MVFR CIGS DURING PRE-DAWN
HOURS. A WEAK COLD FRONT SHOULD PASS THROUGH CLL AND UTS BETWEEN
15 AND 18Z AND THE HOUSTON METRO AREA BETWEEN 18 AND 22Z. EXPECT
SCATTERED SHOWER ACTIVITY AHEAD ON THE FRONT WITH THUNDERSTORM
ACTIVITY POSSIBLE WITH FRONTAL PASSAGE. AT THIS TIME...EXPECT
MOST ACTIVITY TO BE LIMITED TO NORTHERN AND WESTERN PORTIONS OF
THE FORECAST AREA WITH DECREASING ACTIVITY AS THE FRONT APPROACHES
THE COAST.
WINDS DURING THE DAY ON SUNDAY SHOULD BE FROM THE SOUTH NEAR 10
KNOTS...BECOMING WESTERLY AND NORTHWESTERLY FOLLOWING FRONTAL
PASSAGE. 44
&&
.PREV DISCUSSION... /ISSUED 1010 PM CDT SAT OCT 13 2012/
DISCUSSION...
THE COLD FRONT WAS CURRENTLY THROUGH THE PANHANDLE AND MOVING
INTO CENTRAL AND NORTHERN TX. ISOLATED THUNDERSTORMS THAT OCCURRED
OVER BURLESON AND BRAZOS COUNTIES EARLIER THIS EVENING HAVE
DIMINISHED. DID HAVE A CONFIRMED REPORT OF A RAIN WRAPPED TORNADO
WITH THE STORM BETWEEN DIME BOX AND CALDWELL...THAT ACTUALLY
STARTED IN LEE COUNTY NEAR LEXINGTON. KUDOS TO WFO EWX FOR THE
ORIGINAL HEADS UP AND THE SPOTTER REPORTS IN LEE COUNTY THAT
HELPED US CONFIRM THE RADAR SIGNATURE AND WARNING DECISIONS FOR
BURLESON COUNTY. ALSO APPRECIATED THE WEATHER SPOTTER IN BURLESON
COUNTY FOR THE TWO REPORTS DURING THE TORNADO WARNING. HELICITY
VALUES ON THE 00Z AREA SOUNDINGS DID INDICATE SOME POTENTIAL...
WITH 0 TO 3 KM VALUES AT 350 AT FWD...133 AT CRP...AND 257 AT
SHV. THE 18Z NAM BUFR MODEL ACTUALLY SHOWED THE BEST POTENTIAL ON
THE CLL FORECAST SOUNDING FOR EARLIER THIS EVENING.
DO EXPECT THE RAIN CHANCES TO INCREASE OVERNIGHT OVER THE
NORTHWESTERN HALF OF THE FORECAST AREA AS THE FRONT APPROACHES
SE TX. THE RAP MESO-SCALE ANALYSIS INDICATES THIS TREND BY SHOWING
PW/S NEARING 1.8 INCHES OVER THE WESTERN COUNTIES.
THE CURRENT RADAR ALSO SHOWS STREAMER SHOWERS DEVELOPING OFF THE
COAST AS THE MOISTURE ADVECTION WAS INCREASING. DECIDED TO UPDATE
THE FORECAST TO INCLUDE ISOLATED SHOWERS IN THE 10 PERCENT POP
AREAS. THESE ARE LOCATED MAINLY TOWARD THE COAST THIS EVENING...
AND ALONG AND OFF THE COAST OVERNIGHT TONIGHT AND SUNDAY MORNING.
40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 73 86 62 84 59 / 60 50 10 10 0
HOUSTON (IAH) 73 87 64 86 60 / 20 40 30 10 0
GALVESTON (GLS) 76 86 72 83 71 / 10 30 30 10 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 10 AM CDT SUNDAY FOR
THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...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...40
AVIATION/MARINE...44
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
307 PM CDT SUN OCT 14 2012
.SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT
307 PM CDT SUN OCT 14 2012
BIGGEST FORECAST CHALLENGES ARE ON THE TIMING OF THE ENDING OF THE
PRECIPITATION TONIGHT ALONG WITH CLOUD TRENDS. ALSO RAIN CHANCES ON
WEDNESDAY.
18Z SURFACE ANALYSIS SHOWS AN AREA OF LOW PRESSURE OVER NORTHERN
ILLINOIS...WITH RADAR SHOWING A DEFORMATION BAND OF RAIN OVER
SOUTHERN AND CENTRAL WISCONSIN AND NORTHERN ILLINOIS. THE BACK EDGE
HAS STEADILY BEEN MOVING EASTWARD AND NOW EXTENDS FROM AROUND
NEILLSVILLE WISCONSIN...TO MONONA IOWA. VISIBLE SATELLITE IMAGERY
SHOWING BACK EDGE OF CLOUDS PUSHING INTO EASTERN MINNESOTA...WITH A
BATCH OF MID LEVEL CLOUDS OVER NORTHERN MINNESOTA.
14.12Z MODELS OFFER SIMILAR SOLUTIONS THROUGH THE PERIOD. IN THE
NEAR TERM...SURFACE LOW WILL CONTINUE TO PULL NORTHEAST INTO LOWER
MICHIGAN THIS EVENING. DEFORMATION AREA OF RAIN WILL CONTINUE TO
SHIFT EASTWARD. THE 14.12Z RAP AND 14.12Z GFS PUSH THE PRECIPITATION
TO THE EAST OF THE AREA BY 00Z...WHILE THE NAM IS A LITTLE SLOWER.
BASED ON MOVEMENT OF THE BACK EDGE...BELIEVE IT WILL CLEAR THE
FORECAST AREA BY 00Z. QUESTION THEN BECOMES HOW QUICKLY THE SKIES
CLEAR. BOTH THE NAM AND GFS RELATIVE HUMIDITY PROGS SHOW THE LOWER
STRATUS TO ADVECT EASTWARD THIS EVENING...BUT SOME MID LEVEL MOISTURE
AROUND 700MB ROTATES SOUTHWARD FROM NORTHERN MINNESOTA INTO THE
AREA. VISIBLE SATELLITE IMAGERY SHOWS THIS MOISTURE NOW OVER NORTHERN
MINNESOTA. THUS DID ADD DOME MORE CLOUDS TO THE EVENING HOURS BEFORE
CLEARING AFTER MIDNIGHT. BETWEEN THE CLOUDS AND THE PRESSURE
GRADIENT REMAINING TIGHT DO NOT EXPECT ANY FOG FORMATION DESPITE THE WET
GROUND FROM THE RAIN.
SURFACE HIGH PRESSURE BUILDS IN MONDAY...WITH THE RIDGE AXIS
QUICKLY MOVING EAST MONDAY NIGHT. 850MB TEMPERATURES IN THE 5 TO 7
DEGREE RANGE CELSIUS AND PLENTY OF SUN WILL MAKE FOR TEMPERATURES
NEAR THE SEASONAL NORMALS. WARM ADVECTION SPREADS ACROSS THE AREA ON
THE BACK SIDE OF THE HIGH MONDAY NIGHT AS A A WEAK SHORTWAVE DROPS
ACROSS THE PLAINS. FORCING SIGNALS RATHER WEAK AND FEEL BEST CHANCES
FOR PRECIPITATION WILL BE ACROSS THE FAR NORTH.
WARM ADVECTION CONTINUES IN EARNEST ON TUESDAY AS 850MB TEMPERATURES
RISE INTO THE LOWER TEENS CELSIUS. WITH A SOUTHWESTER LOW LEVEL
FLOW...EXPECT TEMPERATURES TO TOP OFF IN THE 60S TO LOWER 70S. A
SHORTWAVE WILL TRANSLATE ALONG THE CANADIAN BORDER WITH SOME WEAK
FORCING ACROSS NORTHERN WISCONSIN. GFS AND ECMWF DO GENERATE SOME
LIGHT QPF ACROSS THE FAR NORTHERN COUNTIES...WHILE NAM IS RELATIVELY
DRY. DID KEEP THE LOWER END PROBABILITIES FOR THIS TIME FRAME.
ON WEDNESDAY...A 130 KNOT 300MB JET DIGS DOWN ACROSS THE ROCKIES
INTO THE PLAINS. IN RESPONSE A STRENGTHENING 500MB CLOSED LOW WILL
DROP SOUTHWARD TO NEAR LAKE WINNIPEG. THIS AMPLIFIED FLOW WILL PUSH
A COLD FRONT ACROSS THE AREA...WITH RATHER IMPRESSIVE COLD ADVECTION
IN ITS WAKE. STRONG DYNAMIC FORCING WITH FGEN SIGNAL PUSHES ACROSS
THE AREA. MODELS CONSISTENT WITH PUSHING A BAND OF PRECIPITATION
ACROSS THE AREA WEDNESDAY. SOME WEAK INSTABILITIES LOOK TO BE
PRESENT ACROSS IOWA AND SOUTHWEST WISCONSIN. DID RAISE PROBABILITIES
IN THIS TIME FRAME AND KEPT THE MENTION OF THUNDER ACROSS THE SOUTH.
THESE PRECIPITATION CHANCES WILL REMAIN WEDNESDAY NIGHT AS 500MB
CLOSED LOW SLOWLY CONTINUES TO SINK SOUTHWARD INTO THE AREA.
.LONG TERM...THURSDAY THROUGH SUNDAY
307 PM CDT SUN OCT 14 2012
THE AFOREMENTIONED 500MB LOW WILL BE THE MAIN WEATHER FEATURE OF
INTEREST AT LEAST THROUGH THE EARLY PORTIONS OF THE WEEKEND. ONCE
AGAIN THE 14.12Z GFS IS FASTER AT OPENING THE WAVE UP AND PUSHING IT
EASTWARD ON SATURDAY...WHILE THE ECMWF MAINTAINS ITS CONTINUITY IN
SLOWLY LIFTING IT NORTHEAST LATER IN THE WEEKEND. GIVEN STRENGTH OF
SYSTEM THE SLOWER SOLUTIONS LOOKS MORE REASONABLE AT THIS POINT. WILL
CONTINUE TO SEE RAIN CHANCES THROUGH THE ENTIRE PERIOD. TEMPERATURES
LOOK TO BE BELOW NORMAL...WITH SLOW WARMING TREND BY SUNDAY AS THE
LOW PUSHES AWAY. WILL HAVE TO WAIT FOR LATER MODEL RUNS TO PIN DOWN
ANY OF THE DETAILS.
&&
.AVIATION...THROUGH 18Z MONDAY
1257 PM CDT SUN OCT 14 2012
LOW PRESSURE WILL CONTINUE TO MOVE NORTHEAST AWAY FROM THE AREA
THIS AFTERNOON. AS THIS OCCURS...THE LIGHT RAIN WILL MOVE OUT KLSE
BY 14.20Z. IN ADDITION...THE CEILINGS WILL SLOWLY RISE AND BECOME
VFR BETWEEN 14.20Z AND 15.01Z. WHILE THE AREA WILL BE LOSING THE
LOW DECK OF CLOUDS...A MID DECK OF CLOUDS WILL MOVE THROUGH THE
AREA TONIGHT...AND THEN SKIES WILL CLEAR AS A WEAK RIDGE BUILDS
ACROSS THE REGION.
WITH ALL OF THE RAIN THIS WEEKEND WAS INITIALLY CONCERNED WITH FOG
TONIGHT...HOWEVER...THE MODEL SOUNDINGS SUGGEST THAT THE WINDS
WILL STAY ABOVE 5 KNOTS. THIS WILL PRECLUDE ANY FOG DEVELOPMENT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
307 PM CDT SUN OCT 14 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RABERDING
LONG TERM...RABERDING
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1257 PM CDT SUN OCT 14 2012
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
258 AM CDT SUN OCT 14 2012
MAIN FORECAST CONCERNS ARE ON PRECIPITATION TODAY AS WELL AS
PRECIPITATION CHANCES FOR MONDAY NIGHT THROUGH TUESDAY NIGHT.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING BUILDING UP ACROSS THE WESTERN U.S. INTO BRITISH
COLUMBIA...A NORTHERN STREAM TROUGH OVER SOUTH CENTRAL CANADA AND
NORTH DAKOTA...AND AN UPPER LOW NEAR TOPEKA KS. ALSO OF INTEREST IS
120KT JET STREAK AROUND 200MB OVER LAKE SUPERIOR ACCORDING TO THE
RAP. THE COMBINATION OF UPPER DIVERGENCE IN THE RIGHT ENTRANCE
REGION OF THIS UPPER JET...THE PRESENCE OF LOW TO MID LEVEL
FRONTOGENESIS OVER THE SOUTHERN HALF OF THE FORECAST AREA SEEN JUST
BY CONVERGENCE IN 850MB PROFILER AND VWP DATA...AND PLENTIFUL
MOISTURE NOTED BY GOES PRECIPITABLE WATER VALUES OF 1.4 INCHES IN
THE SAME PLACE IS RESULTING IN A BAND OF SHOWERS AND EMBEDDED
THUNDERSTORMS. BACK EDGE OF THIS PRECIPITATION ALONG A LINE
EXTENDED FROM CHARLES CITY TO VIROQUA AND WISCONSIN DELLS.
NORTHWEST OF THIS LINE...PRECIPITABLE WATER VALUES DROP OFF
DRAMATICALLY... DOWN TO AROUND 0.75 INCH IN WEST CENTRAL MINNESOTA.
IN FACT...SATELLITE IMAGERY DEPICTS CLEARING OVER WESTERN
MINNESOTA AND THE EASTERN DAKOTAS. AT THE SURFACE...A 998MB LOW
WAS PRESENT IN SOUTHWEST IOWA WITH A WARM FRONT EXTENDING
NORTHEAST INTO SOUTHWEST WISCONSIN.
TODAY...MODELS DEPICT THE NORTHERN STREAM TROUGH OVER SOUTH CENTRAL
CANADA DROPPING DOWN INTO MINNESOTA AND IOWA...WHICH HELPS TO KICK
THE UPPER LOW NEAR TOPEKA NORTHEASTWARD. BY 00Z...MODELS HAVE THE
UPPER LOW AND THE ASSOCIATED SURFACE LOW IN CENTRAL LAKE MICHIGAN...
SLIGHTLY SLOWER THAN SEEN YESTERDAY. THE FORECAST AREA...IN
PARTICULAR THE SOUTHEAST HALF...WILL STAY IN THE DEFORMATION ON THE
NORTHWEST SIDE OF THE LOW TRACK WHICH IS QUITE FAVORABLE FOR
PRECIPITATION. IN FACT...THE CURRENT BAND OF SHOWERS AND EMBEDDED
THUNDERSTORMS SHOULD INTENSIFY THIS MORNING AS DPVA INCREASES FROM
THE APPROACHING UPPER LOW. FRONTOGENESIS FIELDS ALSO STRENGTHEN IN
RESPONSE TO THE INCREASING DPVA. PRECIPITATION WILL TAPER OFF IN THE
AFTERNOON WEST TO EAST AS THE UPPER JET...FRONTOGENESIS AND THE
OVERALL SYSTEM MOVE EAST AWAY FROM THE AREA. DECENT AMOUNT OF QPF
EXPECTED TODAY IN SOUTHEAST SECTIONS OF THE FORECAST AREA GIVEN
THE STRONG FORCING THIS MORNING AND PRECIPITABLE WATER VALUES NEAR
1.5 INCHES. BLEND OF GUIDANCE SUGGESTS UPWARDS OF 1 INCH BETWEEN
12-18Z FROM OELWEIN TO PRAIRIE DU CHIEN AND BOSCOBEL. ALTHOUGH
CLEARING IS NOT TOO FAR AWAY...OVER WESTERN MINNESOTA...14.00Z
NAM/14.03Z RAP SOUNDINGS SUGGEST IT WILL TAKE ITS TIME SHIFTING
EAST AS MOISTURE STAYS TRAPPED BELOW A SUBSIDENCE INVERSION AT
5000 FT. WILL PLAY THIS MORE PESSIMISTIC ROUTE COMPARED TO THE
QUICKER CLEARING GFS GIVEN THAT CLIMATOLOGICALLY CLOUD COVER TENDS
TO HOLD AROUND LONGER. WITH PLENTY OF CLOUDS AND 850MB TEMPS
FALLING FROM 8-12C AT 12Z TO 2-4C AT 00Z...ANTICIPATE TEMPERATURES
TO NOT RISE MUCH. IN FACT...READINGS COULD FALL...ESPECIALLY OVER
THE EASTERN TWO THIRDS OF THE AREA WHICH STAND NO CHANCE OF SEEING
SUN.
TONIGHT AND MONDAY...RAPID EVOLUTION OF THE UPPER AIR PATTERN IS
FORECAST OVER THE AREA DURING THIS TIME. THE NORTHERN STREAM TROUGH
DROPPING INTO IOWA AT 00Z IS PROGGED TO DIG INTO ILLINOIS BY 12Z...
THEN RIDGING SEEN OVER BRITISH COLUMBIA RIGHT NOW EXPECTED TO SHIFT
OVER THE AREA BY 00Z TUESDAY. NOT ANTICIPATING ANY PRECIPITATION
WITH THE NORTHERN STREAM TROUGH...NOR WITH THE WARM ADVECTION
ACCOMPANYING THE UPPER RIDGE BUILDING IN ON MONDAY...AS TOO MUCH
SUBSIDENCE AND DRYING FLOWS IN BEHIND THE CURRENT STORM SYSTEM.
WOULD HAVE SOME CONCERN ABOUT VALLEY FOG TONIGHT WITH SKIES LIKELY
TO CLEAR FROM WEST TO EAST AND LINGERING MOISTURE FROM TODAYS RAIN.
HOWEVER...THERE IS TOO MUCH OF A NORTHWEST BREEZE BETWEEN THE
DEPARTING STORM SYSTEM AND A SURFACE HIGH PRESSURE RIDGE BUILDING
INTO WESTERN MINNESOTA BY 12Z. THIS BREEZE SHOULD HELP KEEP
TEMPERATURES FROM DROPPING TOO MUCH AS WELL. GENERALLY FOLLOWED A
BLEND OF GUIDANCE FOR LOWS. WITH THE PASSAGE OF THE SURFACE RIDGE ON
MONDAY...MORE SUN AND 850MB TEMPS CLIMBING TO 4C EAST TO 7C WEST BY
00Z...SHOULD SEE A WARMER DAY. THE AFOREMENTIONED LATE IN THE DAY
850MB TEMPS SUPPORT HIGHS IN THE MID 50S TO LOWER 60S. THESE ARE
LOWER THAN PREVIOUSLY FORECAST BECAUSE MODELS ARE SLOWER IN BRINGING
THE WARMER AIR IN.
MONDAY NIGHT AND TUESDAY...MODELS DEPICT A SHORTWAVE TROUGH OVER
NORTH DAKOTA AT 00Z TUESDAY...PARTLY RESPONSIBLE FOR THE UPPER RIDGE
THAT MOVED INTO THE AREA ON MONDAY...MOVING QUICKLY TO THE EAST
AND PERHAPS EVEN WEAKENING. THIS WEAKENING MAKES SENSE AS THERE IS A
MUCH MORE IMPRESSIVE AND POTENT UPPER TROUGH DIGGING DOWN INTO THE
NORTHERN U.S. ROCKIES. QUESTION IS IF ANY PRECIPITATION WILL OCCUR
WITH THAT SHORTWAVE TROUGH THAT TRACKS TO OUR NORTH. 14.00Z NAM
KEEPS ALL PRECIPITATION WELL TO THE NORTH...FROM NORTHERN MINNESOTA
INTO THE U.P.. THE 14.00Z GFS SHOWS SOME PRECIP CROSSING THE
NORTHERN SECTIONS OF THE FORECAST AREA...THOUGH VARIOUS ISENTROPIC
LIFT LEVELS FROM 290-310K SHOW VERY LITTLE LIFT OCCURRING WITH IT.
PLUS...THE PRECIPITATION IS FALLING OUT OF A 9000 FT CEILING. ALL
MODELS HAVE CERTAINLY TRENDED DRIER AND LESS IMPRESSIVE WITH THE
SHORTWAVE TROUGH. HAVE DECIDED TO MAINTAIN SOME 20 PERCENT
CHANCES...MAINLY ON TUESDAY NORTHEAST OF I-94. IDEA HERE BEING THAT
IT MAY TAKE AWHILE TO SATURATE THE LOWER LEVELS WITH THE WARM
ADVECTION TO ALLOW PRECIPITATION TO OCCUR. ALTHOUGH WE MAY GET
LITTLE PRECIPITATION OVERALL WITH THE SHORTWAVE TROUGH...THERE IS
DEFINITE WARMING COMING INTO THE FORECAST AREA WITH IT. 850MB TEMPS
CLIMB TO AT LEAST 10-14C BY 18Z TUESDAY. WITH POTENTIAL FOR ANY WARM
ADVECTION MID CLOUDS TO CLEAR OUT ON TUESDAY...COULD SEE DECENT
MIXING. AS SUCH...HAVE BUMPED UP TEMPERATURES ABOUT 5 DEGREES TO
COME IN BETTER ALIGNMENT WITH GUIDANCE. MONDAY NIGHT STILL LOOKS
RELATIVELY MILD THANKS TO THE INCREASE IN MID CLOUDS AND SOME
SOUTHERLY BREEZE.
TUESDAY NIGHT...THE POTENT TROUGH DIGGING INTO THE NORTHERN ROCKIES
ON TUESDAY IS PROGGED TO DIVE DOWN INTO THE DAKOTAS. IMPRESSIVE
WINDY AND COLD ADVECTION SETUP BEHIND IT WITH MODEL PROGS OF A 980S
MB LOW NEAR LAKE WINNIPEG AND 1025-1030MB SURFACE HIGH OVER THE
NORTHWESTERN U.S.. FOR OUR AREA...WE ARE IN THE WARM ADVECTION SETUP
AHEAD OF THE LOW WITH INDICATIONS OF 500MB HEIGHTS FALLING AFTER
MIDNIGHT. THEREFORE...ANTICIPATING SOME MID AND HIGH CLOUDS
SPREADING WEST TO EAST AGAIN...LIKE MONDAY NIGHT. LOWER LEVEL
SATURATION BECOMES AN ISSUE FOR ANY PRECIPITATION TO FALL OUT OF
THESE CLOUDS. BOTH THE 14.00Z GFS AND NAM SUGGEST SOME LIGHT QPF CAN
FALL ACROSS NORTHWEST SECTIONS OF THE FORECAST AREA BETWEEN 06-12Z
WEDNESDAY...WHICH HAVE BEEN ACKNOWLEDGED WITH A 15-20 PERCENT
CHANCE. OTHERWISE...DRY CONDITIONS WITH A LIGHT SOUTHERLY BREEZE
WILL BE THE RULE. COMBINATION OF THAT SOUTHERLY BREEZE AND
CLOUDS...ALONG WITH DEWPOINTS WHICH SHOULD BE UP IN THE 40S IS
EXPECTED TO HELP HOLD LOWS UP IN THE MID 40S TO LOW 50S.
.LONG TERM...WEDNESDAY THROUGH SATURDAY NIGHT
258 AM CDT SUN OCT 14 2012
MAIN STORY FOR THE EXTENDED REVOLVES AROUND THAT POTENT UPPER TROUGH
DROPPING DOWN INTO THE DAKOTAS TUESDAY NIGHT. 14.00Z
ECMWF/GFS/CANADIAN AND GFS ENSEMBLES ALL SHOW THIS TROUGH DIGGING
INTO THE UPPER MISSISSIPPI RIVER VALLEY AND EASTERN MISSOURI RIVER V
REGIONS BY 12Z THURSDAY. AS THIS TROUGH DIGS...IT GRADUALLY PULLS UP
MORE AND MORE MOISTURE FROM THE GULF OF MEXICO. THEREFORE...
PRECIPITATION WITH IT SEEMS LIKELY. BIGGEST PROBLEM IS EVOLUTION OF
THE VARIOUS WARM AND COLD CONVEYOR BELTS AS THIS SYSTEM WRAPS
UP...WITH POTENTIAL OF A DRY SLOT COMING AROUND THE UPPER LOW TOO.
FOLLOWED THE CONSENSUS APPROACH FOR NOW WHICH INCREASES CHANCES TO
AROUND 50 ON WEDNESDAY...WITH THE EXPECTED WARM CONVEYOR BELT...
LOWER 30-40 PERCENT CHANCES ON WEDNESDAY NIGHT WITH A POSSIBLE DRY
SLOT...THEN 50 PERCENT CHANCES OVER MINNESOTA WITH THE COLD CONVEYOR
BELT TO 30 PERCENT CHANCES IN SOUTHEAST SECTIONS OF THE FORECAST
AREA WITH POSSIBLE DRY SLOT ON THURSDAY. AS TIME GETS CLOSER...THESE
CHANCES WILL NEED TO BE FURTHER REFINED WITH INCREASES AGAIN LIKELY.
WEDNESDAY STILL LOOKS RELATIVELY WARM BEING IN THE WARM CONVEYOR
BELT AND 850MB TEMPS UPWARDS OF 8-12C. MOST LOCATIONS SHOULD REACH
THE MID 50S TO MID 60S RANGE...WARMEST EAST WHERE PRECIPITATION
BEGINS LATER. COOLER WEATHER THEN ON TAP FOR THURSDAY WITH THE UPPER
TROUGH IN PLACE AND POSSIBLE PRECIPITATION. ALSO ADDED A MENTION OF
THUNDER TO NORTHEAST IOWA AND FAR SOUTHWEST WISCONSIN ON WEDNESDAY
WHERE BOTH THE 14.00Z GFS/ECMWF DEPICT SOME MUCAPE BUILDING UP.
AFTER THURSDAY...QUESTION IS HOW FAST THE UPPER LOW/TROUGH PUSHES
EAST. THE 14.00Z ECMWF/CANADIAN HAVE RIDGES AMPLIFYING ACROSS THE
WESTERN U.S. AND FROM NEW ENGLAND INTO QUEBEC...EFFECTIVELY BLOCKING
THE TROUGH FROM REALLY GOING ANYWHERE. THE 14.00Z GFS AND QUITE A
FEW OF ITS ENSEMBLE MEMBERS DO NOT HAVE AS MUCH RIDGING OVER NEW
ENGLAND AND QUEBEC...THUS ALLOWING THE TROUGH TO LIFT OUT. THINK
THIS LATTER SCENARIO IS TOO FAST AND THUS LEANING THE FORECAST MORE
TOWARDS THE CONSISTENT ECMWF/CANADIAN SOLUTIONS. THIS RESULTS IN
MAINTAINING COOL WEATHER WITH HIGHS IN THE LOW TO MID 50S ALONG WITH
LOW CHANCES OF PRECIPITATION THROUGH SATURDAY. REASON FOR THE LOW
PRECIPITATION CHANCES...GENERALLY 20-30...IS A COMBINATION OF MODEL
UNCERTAINTY ON THE EVOLUTION/TRACK OF THE UPPER LOW/TROUGH AS WELL
AS SUGGESTIONS OF THE UPPER LOW/TROUGH FILLING WITH TIME.
&&
.AVIATION...THROUGH 18Z MONDAY
1257 PM CDT SUN OCT 14 2012
LOW PRESSURE WILL CONTINUE TO MOVE NORTHEAST AWAY FROM THE AREA
THIS AFTERNOON. AS THIS OCCURS...THE LIGHT RAIN WILL MOVE OUT KLSE
BY 14.20Z. IN ADDITION...THE CEILINGS WILL SLOWLY RISE AND BECOME
VFR BETWEEN 14.20Z AND 15.01Z. WHILE THE AREA WILL BE LOSING THE
LOW DECK OF CLOUDS...A MID DECK OF CLOUDS WILL MOVE THROUGH THE
AREA TONIGHT...AND THEN SKIES WILL CLEAR AS A WEAK RIDGE BUILDS
ACROSS THE REGION.
WITH ALL OF THE RAIN THIS WEEKEND WAS INITIALLY CONCERNED WITH FOG
TONIGHT...HOWEVER...THE MODEL SOUNDINGS SUGGEST THAT THE WINDS
WILL STAY ABOVE 5 KNOTS. THIS WILL PRECLUDE ANY FOG DEVELOPMENT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
258 AM CDT SUN OCT 14 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
641 AM CDT SUN OCT 14 2012
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
258 AM CDT SUN OCT 14 2012
MAIN FORECAST CONCERNS ARE ON PRECIPITATION TODAY AS WELL AS
PRECIPITATION CHANCES FOR MONDAY NIGHT THROUGH TUESDAY NIGHT.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING BUILDING UP ACROSS THE WESTERN U.S. INTO BRITISH
COLUMBIA...A NORTHERN STREAM TROUGH OVER SOUTH CENTRAL CANADA AND
NORTH DAKOTA...AND AN UPPER LOW NEAR TOPEKA KS. ALSO OF INTEREST IS
120KT JET STREAK AROUND 200MB OVER LAKE SUPERIOR ACCORDING TO THE
RAP. THE COMBINATION OF UPPER DIVERGENCE IN THE RIGHT ENTRANCE
REGION OF THIS UPPER JET...THE PRESENCE OF LOW TO MID LEVEL
FRONTOGENESIS OVER THE SOUTHERN HALF OF THE FORECAST AREA SEEN JUST
BY CONVERGENCE IN 850MB PROFILER AND VWP DATA...AND PLENTIFUL
MOISTURE NOTED BY GOES PRECIPITABLE WATER VALUES OF 1.4 INCHES IN
THE SAME PLACE IS RESULTING IN A BAND OF SHOWERS AND EMBEDDED
THUNDERSTORMS. BACK EDGE OF THIS PRECIPITATION ALONG A LINE
EXTENDED FROM CHARLES CITY TO VIROQUA AND WISCONSIN DELLS.
NORTHWEST OF THIS LINE...PRECIPITABLE WATER VALUES DROP OFF
DRAMATICALLY... DOWN TO AROUND 0.75 INCH IN WEST CENTRAL MINNESOTA.
IN FACT...SATELLITE IMAGERY DEPICTS CLEARING OVER WESTERN
MINNESOTA AND THE EASTERN DAKOTAS. AT THE SURFACE...A 998MB LOW
WAS PRESENT IN SOUTHWEST IOWA WITH A WARM FRONT EXTENDING
NORTHEAST INTO SOUTHWEST WISCONSIN.
TODAY...MODELS DEPICT THE NORTHERN STREAM TROUGH OVER SOUTH CENTRAL
CANADA DROPPING DOWN INTO MINNESOTA AND IOWA...WHICH HELPS TO KICK
THE UPPER LOW NEAR TOPEKA NORTHEASTWARD. BY 00Z...MODELS HAVE THE
UPPER LOW AND THE ASSOCIATED SURFACE LOW IN CENTRAL LAKE MICHIGAN...
SLIGHTLY SLOWER THAN SEEN YESTERDAY. THE FORECAST AREA...IN
PARTICULAR THE SOUTHEAST HALF...WILL STAY IN THE DEFORMATION ON THE
NORTHWEST SIDE OF THE LOW TRACK WHICH IS QUITE FAVORABLE FOR
PRECIPITATION. IN FACT...THE CURRENT BAND OF SHOWERS AND EMBEDDED
THUNDERSTORMS SHOULD INTENSIFY THIS MORNING AS DPVA INCREASES FROM
THE APPROACHING UPPER LOW. FRONTOGENESIS FIELDS ALSO STRENGTHEN IN
RESPONSE TO THE INCREASING DPVA. PRECIPITATION WILL TAPER OFF IN THE
AFTERNOON WEST TO EAST AS THE UPPER JET...FRONTOGENESIS AND THE
OVERALL SYSTEM MOVE EAST AWAY FROM THE AREA. DECENT AMOUNT OF QPF
EXPECTED TODAY IN SOUTHEAST SECTIONS OF THE FORECAST AREA GIVEN
THE STRONG FORCING THIS MORNING AND PRECIPITABLE WATER VALUES NEAR
1.5 INCHES. BLEND OF GUIDANCE SUGGESTS UPWARDS OF 1 INCH BETWEEN
12-18Z FROM OELWEIN TO PRAIRIE DU CHIEN AND BOSCOBEL. ALTHOUGH
CLEARING IS NOT TOO FAR AWAY...OVER WESTERN MINNESOTA...14.00Z
NAM/14.03Z RAP SOUNDINGS SUGGEST IT WILL TAKE ITS TIME SHIFTING
EAST AS MOISTURE STAYS TRAPPED BELOW A SUBSIDENCE INVERSION AT
5000 FT. WILL PLAY THIS MORE PESSIMISTIC ROUTE COMPARED TO THE
QUICKER CLEARING GFS GIVEN THAT CLIMATOLOGICALLY CLOUD COVER TENDS
TO HOLD AROUND LONGER. WITH PLENTY OF CLOUDS AND 850MB TEMPS
FALLING FROM 8-12C AT 12Z TO 2-4C AT 00Z...ANTICIPATE TEMPERATURES
TO NOT RISE MUCH. IN FACT...READINGS COULD FALL...ESPECIALLY OVER
THE EASTERN TWO THIRDS OF THE AREA WHICH STAND NO CHANCE OF SEEING
SUN.
TONIGHT AND MONDAY...RAPID EVOLUTION OF THE UPPER AIR PATTERN IS
FORECAST OVER THE AREA DURING THIS TIME. THE NORTHERN STREAM TROUGH
DROPPING INTO IOWA AT 00Z IS PROGGED TO DIG INTO ILLINOIS BY 12Z...
THEN RIDGING SEEN OVER BRITISH COLUMBIA RIGHT NOW EXPECTED TO SHIFT
OVER THE AREA BY 00Z TUESDAY. NOT ANTICIPATING ANY PRECIPITATION
WITH THE NORTHERN STREAM TROUGH...NOR WITH THE WARM ADVECTION
ACCOMPANYING THE UPPER RIDGE BUILDING IN ON MONDAY...AS TOO MUCH
SUBSIDENCE AND DRYING FLOWS IN BEHIND THE CURRENT STORM SYSTEM.
WOULD HAVE SOME CONCERN ABOUT VALLEY FOG TONIGHT WITH SKIES LIKELY
TO CLEAR FROM WEST TO EAST AND LINGERING MOISTURE FROM TODAYS RAIN.
HOWEVER...THERE IS TOO MUCH OF A NORTHWEST BREEZE BETWEEN THE
DEPARTING STORM SYSTEM AND A SURFACE HIGH PRESSURE RIDGE BUILDING
INTO WESTERN MINNESOTA BY 12Z. THIS BREEZE SHOULD HELP KEEP
TEMPERATURES FROM DROPPING TOO MUCH AS WELL. GENERALLY FOLLOWED A
BLEND OF GUIDANCE FOR LOWS. WITH THE PASSAGE OF THE SURFACE RIDGE ON
MONDAY...MORE SUN AND 850MB TEMPS CLIMBING TO 4C EAST TO 7C WEST BY
00Z...SHOULD SEE A WARMER DAY. THE AFOREMENTIONED LATE IN THE DAY
850MB TEMPS SUPPORT HIGHS IN THE MID 50S TO LOWER 60S. THESE ARE
LOWER THAN PREVIOUSLY FORECAST BECAUSE MODELS ARE SLOWER IN BRINGING
THE WARMER AIR IN.
MONDAY NIGHT AND TUESDAY...MODELS DEPICT A SHORTWAVE TROUGH OVER
NORTH DAKOTA AT 00Z TUESDAY...PARTLY RESPONSIBLE FOR THE UPPER RIDGE
THAT MOVED INTO THE AREA ON MONDAY...MOVING QUICKLY TO THE EAST
AND PERHAPS EVEN WEAKENING. THIS WEAKENING MAKES SENSE AS THERE IS A
MUCH MORE IMPRESSIVE AND POTENT UPPER TROUGH DIGGING DOWN INTO THE
NORTHERN U.S. ROCKIES. QUESTION IS IF ANY PRECIPITATION WILL OCCUR
WITH THAT SHORTWAVE TROUGH THAT TRACKS TO OUR NORTH. 14.00Z NAM
KEEPS ALL PRECIPITATION WELL TO THE NORTH...FROM NORTHERN MINNESOTA
INTO THE U.P.. THE 14.00Z GFS SHOWS SOME PRECIP CROSSING THE
NORTHERN SECTIONS OF THE FORECAST AREA...THOUGH VARIOUS ISENTROPIC
LIFT LEVELS FROM 290-310K SHOW VERY LITTLE LIFT OCCURRING WITH IT.
PLUS...THE PRECIPITATION IS FALLING OUT OF A 9000 FT CEILING. ALL
MODELS HAVE CERTAINLY TRENDED DRIER AND LESS IMPRESSIVE WITH THE
SHORTWAVE TROUGH. HAVE DECIDED TO MAINTAIN SOME 20 PERCENT
CHANCES...MAINLY ON TUESDAY NORTHEAST OF I-94. IDEA HERE BEING THAT
IT MAY TAKE AWHILE TO SATURATE THE LOWER LEVELS WITH THE WARM
ADVECTION TO ALLOW PRECIPITATION TO OCCUR. ALTHOUGH WE MAY GET
LITTLE PRECIPITATION OVERALL WITH THE SHORTWAVE TROUGH...THERE IS
DEFINITE WARMING COMING INTO THE FORECAST AREA WITH IT. 850MB TEMPS
CLIMB TO AT LEAST 10-14C BY 18Z TUESDAY. WITH POTENTIAL FOR ANY WARM
ADVECTION MID CLOUDS TO CLEAR OUT ON TUESDAY...COULD SEE DECENT
MIXING. AS SUCH...HAVE BUMPED UP TEMPERATURES ABOUT 5 DEGREES TO
COME IN BETTER ALIGNMENT WITH GUIDANCE. MONDAY NIGHT STILL LOOKS
RELATIVELY MILD THANKS TO THE INCREASE IN MID CLOUDS AND SOME
SOUTHERLY BREEZE.
TUESDAY NIGHT...THE POTENT TROUGH DIGGING INTO THE NORTHERN ROCKIES
ON TUESDAY IS PROGGED TO DIVE DOWN INTO THE DAKOTAS. IMPRESSIVE
WINDY AND COLD ADVECTION SETUP BEHIND IT WITH MODEL PROGS OF A 980S
MB LOW NEAR LAKE WINNIPEG AND 1025-1030MB SURFACE HIGH OVER THE
NORTHWESTERN U.S.. FOR OUR AREA...WE ARE IN THE WARM ADVECTION SETUP
AHEAD OF THE LOW WITH INDICATIONS OF 500MB HEIGHTS FALLING AFTER
MIDNIGHT. THEREFORE...ANTICIPATING SOME MID AND HIGH CLOUDS
SPREADING WEST TO EAST AGAIN...LIKE MONDAY NIGHT. LOWER LEVEL
SATURATION BECOMES AN ISSUE FOR ANY PRECIPITATION TO FALL OUT OF
THESE CLOUDS. BOTH THE 14.00Z GFS AND NAM SUGGEST SOME LIGHT QPF CAN
FALL ACROSS NORTHWEST SECTIONS OF THE FORECAST AREA BETWEEN 06-12Z
WEDNESDAY...WHICH HAVE BEEN ACKNOWLEDGED WITH A 15-20 PERCENT
CHANCE. OTHERWISE...DRY CONDITIONS WITH A LIGHT SOUTHERLY BREEZE
WILL BE THE RULE. COMBINATION OF THAT SOUTHERLY BREEZE AND
CLOUDS...ALONG WITH DEWPOINTS WHICH SHOULD BE UP IN THE 40S IS
EXPECTED TO HELP HOLD LOWS UP IN THE MID 40S TO LOW 50S.
.LONG TERM...WEDNESDAY THROUGH SATURDAY NIGHT
258 AM CDT SUN OCT 14 2012
MAIN STORY FOR THE EXTENDED REVOLVES AROUND THAT POTENT UPPER TROUGH
DROPPING DOWN INTO THE DAKOTAS TUESDAY NIGHT. 14.00Z
ECMWF/GFS/CANADIAN AND GFS ENSEMBLES ALL SHOW THIS TROUGH DIGGING
INTO THE UPPER MISSISSIPPI RIVER VALLEY AND EASTERN MISSOURI RIVER V
REGIONS BY 12Z THURSDAY. AS THIS TROUGH DIGS...IT GRADUALLY PULLS UP
MORE AND MORE MOISTURE FROM THE GULF OF MEXICO. THEREFORE...
PRECIPITATION WITH IT SEEMS LIKELY. BIGGEST PROBLEM IS EVOLUTION OF
THE VARIOUS WARM AND COLD CONVEYOR BELTS AS THIS SYSTEM WRAPS
UP...WITH POTENTIAL OF A DRY SLOT COMING AROUND THE UPPER LOW TOO.
FOLLOWED THE CONSENSUS APPROACH FOR NOW WHICH INCREASES CHANCES TO
AROUND 50 ON WEDNESDAY...WITH THE EXPECTED WARM CONVEYOR BELT...
LOWER 30-40 PERCENT CHANCES ON WEDNESDAY NIGHT WITH A POSSIBLE DRY
SLOT...THEN 50 PERCENT CHANCES OVER MINNESOTA WITH THE COLD CONVEYOR
BELT TO 30 PERCENT CHANCES IN SOUTHEAST SECTIONS OF THE FORECAST
AREA WITH POSSIBLE DRY SLOT ON THURSDAY. AS TIME GETS CLOSER...THESE
CHANCES WILL NEED TO BE FURTHER REFINED WITH INCREASES AGAIN LIKELY.
WEDNESDAY STILL LOOKS RELATIVELY WARM BEING IN THE WARM CONVEYOR
BELT AND 850MB TEMPS UPWARDS OF 8-12C. MOST LOCATIONS SHOULD REACH
THE MID 50S TO MID 60S RANGE...WARMEST EAST WHERE PRECIPITATION
BEGINS LATER. COOLER WEATHER THEN ON TAP FOR THURSDAY WITH THE UPPER
TROUGH IN PLACE AND POSSIBLE PRECIPITATION. ALSO ADDED A MENTION OF
THUNDER TO NORTHEAST IOWA AND FAR SOUTHWEST WISCONSIN ON WEDNESDAY
WHERE BOTH THE 14.00Z GFS/ECMWF DEPICT SOME MUCAPE BUILDING UP.
AFTER THURSDAY...QUESTION IS HOW FAST THE UPPER LOW/TROUGH PUSHES
EAST. THE 14.00Z ECMWF/CANADIAN HAVE RIDGES AMPLIFYING ACROSS THE
WESTERN U.S. AND FROM NEW ENGLAND INTO QUEBEC...EFFECTIVELY BLOCKING
THE TROUGH FROM REALLY GOING ANYWHERE. THE 14.00Z GFS AND QUITE A
FEW OF ITS ENSEMBLE MEMBERS DO NOT HAVE AS MUCH RIDGING OVER NEW
ENGLAND AND QUEBEC...THUS ALLOWING THE TROUGH TO LIFT OUT. THINK
THIS LATTER SCENARIO IS TOO FAST AND THUS LEANING THE FORECAST MORE
TOWARDS THE CONSISTENT ECMWF/CANADIAN SOLUTIONS. THIS RESULTS IN
MAINTAINING COOL WEATHER WITH HIGHS IN THE LOW TO MID 50S ALONG WITH
LOW CHANCES OF PRECIPITATION THROUGH SATURDAY. REASON FOR THE LOW
PRECIPITATION CHANCES...GENERALLY 20-30...IS A COMBINATION OF MODEL
UNCERTAINTY ON THE EVOLUTION/TRACK OF THE UPPER LOW/TROUGH AS WELL
AS SUGGESTIONS OF THE UPPER LOW/TROUGH FILLING WITH TIME.
&&
.AVIATION...TODAY AND TONIGHT
641 AM CDT SUN OCT 14 2012
IFR/LIFR CONDITIONS WILL PERSIST AT THE TAF SITES THROUGH MID
MORNING AS A LOW PRESSURE SYSTEM LIFTS INTO NORTHERN ILLINOIS.
RAIN SHOWERS WILL CONTINUE AT KRST FOR A FEW MORE HOURS THIS
MORNING BEFORE ENDING AND SHIFTING EAST. THE RAIN IS EXPECTED TO
PERSIST AT KLSE THROUGH EARLY THIS AFTERNOON. CEILINGS THIS
MORNING WILL RANGE FROM 200 FT AT KRST TO AROUND 700 FT AT KSLE IN
LOW STRATUS. PLAN ON VISIBILITIES IN THE 4 TO 5 SM RANGE IN RAIN
AND BR. THE LOW WILL SHIFT EAST OF THE AREA THIS AFTERNOON WITH
SHOWERS ENDING AND CONDITIONS RAPIDLY IMPROVING TO MVFR AS
NORTHWEST WINDS INCREASE AND USHER IN DRIER AIR. LOOK FOR
CEILINGS TO RISE TO AROUND 1500 FT AT KRST BY 17Z...THEN
INCREASING TO AROUND 3500 FT BY 21Z WITH CLOUDS BECOMING
SCATTERED LATE IN THE AFTERNOON. THE STRATUS WILL LINGER A LITTLE
LONGER AT KLSE WITH CEILINGS CLIMBING TO AROUND 1000FT BY
16Z..THEN GRADUALLY RISING THROUGH THE AFTERNOON HOURS TO AROUND
3000 FT BY 22Z. VFR CONDITIONS ARE EXPECTED AT THE TAF SITES THIS
EVENING INTO THE OVERNIGHT HOURS AS HIGH PRESSURE BUILDS IN. WILL
HAVE TO KEEP AN EYE ON SHALLOW FOG POTENTIAL AT KLSE GIVEN THE
RECENT RAINS AND WINDS BECOMING LIGHT LATE TONIGHT. AT THIS TIME
IT APPEARS WINDS FROM JUST ABOVE THE SURFACE THROUGH 1 KFT WILL
STAY IN THE 12 TO 20 KT RANGE AND PROMOTE ENOUGH MIXING TO PREVENT
FOG DEVELOPMENT SO WILL NOT INCLUDE IT IN THE TAF AT THIS TIME.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
258 AM CDT SUN OCT 14 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...WETENKAMP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
452 AM CDT SUN OCT 14 2012
.UPDATE...FOR TODAY
452 AM CDT SUN OCT 14 2012
14.06Z NAM...14.08Z RAP AND RADAR TRENDS SHOWING THAT THE
DEFORMATION BAND IS SHIFTING FARTHER NORTHWEST. AFTER SEEING THE
14.06Z NAM...DID TREND THE FORECAST MORE TOWARDS ITS SCENARIO.
HOWEVER...IT IS POSSIBLE THE DEFORMATION BAND GOES FARTHER
NORTHWEST. IN ADDITION...AS WE HEAD INTO THE AFTERNOON AND IN
PARTICULAR THE LATE AFTERNOON HOURS...THE BAND MAY LAST LONGER IN
WISCONSIN THAN CURRENTLY FORECAST. THIS WILL HAVE TO BE MONITORED.
ALSO OF NOTE IS THE QPF WITH THIS DEFORMATION BAND. THE RAIN AS
PREVIOUSLY MENTIONED IN THE SHORT TERM SHOULD ONLY INTENSIFY AS THE
UPPER LOW NOW NEAR THE KANSAS CITY AREA APPROACHES. CROSS-SECTIONS
OF FN VECTORS SHOW A STRONG FRONTOGENESIS-FRONTOLYSIS COUPLET AT 12Z
AND 15Z...WHILE PLAN VIEWS OF THE 310 K SURFACE AND 500MB
TEMPERATURE SHOW A TROWAL SIGNATURE. AS SUCH...FROM 12-18Z TODAY WE
COULD BE SEEING SOME PRETTY HEAVY RAIN...ESPECIALLY COMPARED WITH
WHAT WE HAVE OBSERVED FOR THE PAST FEW MONTHS. THE LAST TIME LA
CROSSE TALLIED MORE THAN 1 INCH OF RAIN WAS AUGUST 4TH. HAVE THE
FORECAST SET AT A MAX AROUND 1.7 INCHES NEAR VIROQUA TODAY...BUT THE
NAM SUGGESTS IT COULD BE EVEN UPWARDS OF 3 INCHES. THUS QPF WILL
NEED MONITORING TOO. THE RAIN COULD RESULT IN PONDING OF WATER ON
ROADWAYS...ESPECIALLY WHERE THERE ARE LEAVES CLOGGING STORM DRAINS.
&&
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
258 AM CDT SUN OCT 14 2012
MAIN FORECAST CONCERNS ARE ON PRECIPITATION TODAY AS WELL AS
PRECIPITATION CHANCES FOR MONDAY NIGHT THROUGH TUESDAY NIGHT.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING BUILDING UP ACROSS THE WESTERN U.S. INTO BRITISH
COLUMBIA...A NORTHERN STREAM TROUGH OVER SOUTH CENTRAL CANADA AND
NORTH DAKOTA...AND AN UPPER LOW NEAR TOPEKA KS. ALSO OF INTEREST IS
120KT JET STREAK AROUND 200MB OVER LAKE SUPERIOR ACCORDING TO THE
RAP. THE COMBINATION OF UPPER DIVERGENCE IN THE RIGHT ENTRANCE
REGION OF THIS UPPER JET...THE PRESENCE OF LOW TO MID LEVEL
FRONTOGENESIS OVER THE SOUTHERN HALF OF THE FORECAST AREA SEEN JUST
BY CONVERGENCE IN 850MB PROFILER AND VWP DATA...AND PLENTIFUL
MOISTURE NOTED BY GOES PRECIPITABLE WATER VALUES OF 1.4 INCHES IN
THE SAME PLACE IS RESULTING IN A BAND OF SHOWERS AND EMBEDDED
THUNDERSTORMS. BACK EDGE OF THIS PRECIPITATION ALONG A LINE
EXTENDED FROM CHARLES CITY TO VIROQUA AND WISCONSIN DELLS.
NORTHWEST OF THIS LINE...PRECIPITABLE WATER VALUES DROP OFF
DRAMATICALLY... DOWN TO AROUND 0.75 INCH IN WEST CENTRAL MINNESOTA.
IN FACT...SATELLITE IMAGERY DEPICTS CLEARING OVER WESTERN
MINNESOTA AND THE EASTERN DAKOTAS. AT THE SURFACE...A 998MB LOW
WAS PRESENT IN SOUTHWEST IOWA WITH A WARM FRONT EXTENDING
NORTHEAST INTO SOUTHWEST WISCONSIN.
TODAY...MODELS DEPICT THE NORTHERN STREAM TROUGH OVER SOUTH CENTRAL
CANADA DROPPING DOWN INTO MINNESOTA AND IOWA...WHICH HELPS TO KICK
THE UPPER LOW NEAR TOPEKA NORTHEASTWARD. BY 00Z...MODELS HAVE THE
UPPER LOW AND THE ASSOCIATED SURFACE LOW IN CENTRAL LAKE MICHIGAN...
SLIGHTLY SLOWER THAN SEEN YESTERDAY. THE FORECAST AREA...IN
PARTICULAR THE SOUTHEAST HALF...WILL STAY IN THE DEFORMATION ON THE
NORTHWEST SIDE OF THE LOW TRACK WHICH IS QUITE FAVORABLE FOR
PRECIPITATION. IN FACT...THE CURRENT BAND OF SHOWERS AND EMBEDDED
THUNDERSTORMS SHOULD INTENSIFY THIS MORNING AS DPVA INCREASES FROM
THE APPROACHING UPPER LOW. FRONTOGENESIS FIELDS ALSO STRENGTHEN IN
RESPONSE TO THE INCREASING DPVA. PRECIPITATION WILL TAPER OFF IN THE
AFTERNOON WEST TO EAST AS THE UPPER JET...FRONTOGENESIS AND THE
OVERALL SYSTEM MOVE EAST AWAY FROM THE AREA. DECENT AMOUNT OF QPF
EXPECTED TODAY IN SOUTHEAST SECTIONS OF THE FORECAST AREA GIVEN
THE STRONG FORCING THIS MORNING AND PRECIPITABLE WATER VALUES NEAR
1.5 INCHES. BLEND OF GUIDANCE SUGGESTS UPWARDS OF 1 INCH BETWEEN
12-18Z FROM OELWEIN TO PRAIRIE DU CHIEN AND BOSCOBEL. ALTHOUGH
CLEARING IS NOT TOO FAR AWAY...OVER WESTERN MINNESOTA...14.00Z
NAM/14.03Z RAP SOUNDINGS SUGGEST IT WILL TAKE ITS TIME SHIFTING
EAST AS MOISTURE STAYS TRAPPED BELOW A SUBSIDENCE INVERSION AT
5000 FT. WILL PLAY THIS MORE PESSIMISTIC ROUTE COMPARED TO THE
QUICKER CLEARING GFS GIVEN THAT CLIMATOLOGICALLY CLOUD COVER TENDS
TO HOLD AROUND LONGER. WITH PLENTY OF CLOUDS AND 850MB TEMPS
FALLING FROM 8-12C AT 12Z TO 2-4C AT 00Z...ANTICIPATE TEMPERATURES
TO NOT RISE MUCH. IN FACT...READINGS COULD FALL...ESPECIALLY OVER
THE EASTERN TWO THIRDS OF THE AREA WHICH STAND NO CHANCE OF SEEING
SUN.
TONIGHT AND MONDAY...RAPID EVOLUTION OF THE UPPER AIR PATTERN IS
FORECAST OVER THE AREA DURING THIS TIME. THE NORTHERN STREAM TROUGH
DROPPING INTO IOWA AT 00Z IS PROGGED TO DIG INTO ILLINOIS BY 12Z...
THEN RIDGING SEEN OVER BRITISH COLUMBIA RIGHT NOW EXPECTED TO SHIFT
OVER THE AREA BY 00Z TUESDAY. NOT ANTICIPATING ANY PRECIPITATION
WITH THE NORTHERN STREAM TROUGH...NOR WITH THE WARM ADVECTION
ACCOMPANYING THE UPPER RIDGE BUILDING IN ON MONDAY...AS TOO MUCH
SUBSIDENCE AND DRYING FLOWS IN BEHIND THE CURRENT STORM SYSTEM.
WOULD HAVE SOME CONCERN ABOUT VALLEY FOG TONIGHT WITH SKIES LIKELY
TO CLEAR FROM WEST TO EAST AND LINGERING MOISTURE FROM TODAYS RAIN.
HOWEVER...THERE IS TOO MUCH OF A NORTHWEST BREEZE BETWEEN THE
DEPARTING STORM SYSTEM AND A SURFACE HIGH PRESSURE RIDGE BUILDING
INTO WESTERN MINNESOTA BY 12Z. THIS BREEZE SHOULD HELP KEEP
TEMPERATURES FROM DROPPING TOO MUCH AS WELL. GENERALLY FOLLOWED A
BLEND OF GUIDANCE FOR LOWS. WITH THE PASSAGE OF THE SURFACE RIDGE ON
MONDAY...MORE SUN AND 850MB TEMPS CLIMBING TO 4C EAST TO 7C WEST BY
00Z...SHOULD SEE A WARMER DAY. THE AFOREMENTIONED LATE IN THE DAY
850MB TEMPS SUPPORT HIGHS IN THE MID 50S TO LOWER 60S. THESE ARE
LOWER THAN PREVIOUSLY FORECAST BECAUSE MODELS ARE SLOWER IN BRINGING
THE WARMER AIR IN.
MONDAY NIGHT AND TUESDAY...MODELS DEPICT A SHORTWAVE TROUGH OVER
NORTH DAKOTA AT 00Z TUESDAY...PARTLY RESPONSIBLE FOR THE UPPER RIDGE
THAT MOVED INTO THE AREA ON MONDAY...MOVING QUICKLY TO THE EAST
AND PERHAPS EVEN WEAKENING. THIS WEAKENING MAKES SENSE AS THERE IS A
MUCH MORE IMPRESSIVE AND POTENT UPPER TROUGH DIGGING DOWN INTO THE
NORTHERN U.S. ROCKIES. QUESTION IS IF ANY PRECIPITATION WILL OCCUR
WITH THAT SHORTWAVE TROUGH THAT TRACKS TO OUR NORTH. 14.00Z NAM
KEEPS ALL PRECIPITATION WELL TO THE NORTH...FROM NORTHERN MINNESOTA
INTO THE U.P.. THE 14.00Z GFS SHOWS SOME PRECIP CROSSING THE
NORTHERN SECTIONS OF THE FORECAST AREA...THOUGH VARIOUS ISENTROPIC
LIFT LEVELS FROM 290-310K SHOW VERY LITTLE LIFT OCCURRING WITH IT.
PLUS...THE PRECIPITATION IS FALLING OUT OF A 9000 FT CEILING. ALL
MODELS HAVE CERTAINLY TRENDED DRIER AND LESS IMPRESSIVE WITH THE
SHORTWAVE TROUGH. HAVE DECIDED TO MAINTAIN SOME 20 PERCENT
CHANCES...MAINLY ON TUESDAY NORTHEAST OF I-94. IDEA HERE BEING THAT
IT MAY TAKE AWHILE TO SATURATE THE LOWER LEVELS WITH THE WARM
ADVECTION TO ALLOW PRECIPITATION TO OCCUR. ALTHOUGH WE MAY GET
LITTLE PRECIPITATION OVERALL WITH THE SHORTWAVE TROUGH...THERE IS
DEFINITE WARMING COMING INTO THE FORECAST AREA WITH IT. 850MB TEMPS
CLIMB TO AT LEAST 10-14C BY 18Z TUESDAY. WITH POTENTIAL FOR ANY WARM
ADVECTION MID CLOUDS TO CLEAR OUT ON TUESDAY...COULD SEE DECENT
MIXING. AS SUCH...HAVE BUMPED UP TEMPERATURES ABOUT 5 DEGREES TO
COME IN BETTER ALIGNMENT WITH GUIDANCE. MONDAY NIGHT STILL LOOKS
RELATIVELY MILD THANKS TO THE INCREASE IN MID CLOUDS AND SOME
SOUTHERLY BREEZE.
TUESDAY NIGHT...THE POTENT TROUGH DIGGING INTO THE NORTHERN ROCKIES
ON TUESDAY IS PROGGED TO DIVE DOWN INTO THE DAKOTAS. IMPRESSIVE
WINDY AND COLD ADVECTION SETUP BEHIND IT WITH MODEL PROGS OF A 980S
MB LOW NEAR LAKE WINNIPEG AND 1025-1030MB SURFACE HIGH OVER THE
NORTHWESTERN U.S.. FOR OUR AREA...WE ARE IN THE WARM ADVECTION SETUP
AHEAD OF THE LOW WITH INDICATIONS OF 500MB HEIGHTS FALLING AFTER
MIDNIGHT. THEREFORE...ANTICIPATING SOME MID AND HIGH CLOUDS
SPREADING WEST TO EAST AGAIN...LIKE MONDAY NIGHT. LOWER LEVEL
SATURATION BECOMES AN ISSUE FOR ANY PRECIPITATION TO FALL OUT OF
THESE CLOUDS. BOTH THE 14.00Z GFS AND NAM SUGGEST SOME LIGHT QPF CAN
FALL ACROSS NORTHWEST SECTIONS OF THE FORECAST AREA BETWEEN 06-12Z
WEDNESDAY...WHICH HAVE BEEN ACKNOWLEDGED WITH A 15-20 PERCENT
CHANCE. OTHERWISE...DRY CONDITIONS WITH A LIGHT SOUTHERLY BREEZE
WILL BE THE RULE. COMBINATION OF THAT SOUTHERLY BREEZE AND
CLOUDS...ALONG WITH DEWPOINTS WHICH SHOULD BE UP IN THE 40S IS
EXPECTED TO HELP HOLD LOWS UP IN THE MID 40S TO LOW 50S.
.LONG TERM...WEDNESDAY THROUGH SATURDAY NIGHT
258 AM CDT SUN OCT 14 2012
MAIN STORY FOR THE EXTENDED REVOLVES AROUND THAT POTENT UPPER TROUGH
DROPPING DOWN INTO THE DAKOTAS TUESDAY NIGHT. 14.00Z
ECMWF/GFS/CANADIAN AND GFS ENSEMBLES ALL SHOW THIS TROUGH DIGGING
INTO THE UPPER MISSISSIPPI RIVER VALLEY AND EASTERN MISSOURI RIVER V
REGIONS BY 12Z THURSDAY. AS THIS TROUGH DIGS...IT GRADUALLY PULLS UP
MORE AND MORE MOISTURE FROM THE GULF OF MEXICO. THEREFORE...
PRECIPITATION WITH IT SEEMS LIKELY. BIGGEST PROBLEM IS EVOLUTION OF
THE VARIOUS WARM AND COLD CONVEYOR BELTS AS THIS SYSTEM WRAPS
UP...WITH POTENTIAL OF A DRY SLOT COMING AROUND THE UPPER LOW TOO.
FOLLOWED THE CONSENSUS APPROACH FOR NOW WHICH INCREASES CHANCES TO
AROUND 50 ON WEDNESDAY...WITH THE EXPECTED WARM CONVEYOR BELT...
LOWER 30-40 PERCENT CHANCES ON WEDNESDAY NIGHT WITH A POSSIBLE DRY
SLOT...THEN 50 PERCENT CHANCES OVER MINNESOTA WITH THE COLD CONVEYOR
BELT TO 30 PERCENT CHANCES IN SOUTHEAST SECTIONS OF THE FORECAST
AREA WITH POSSIBLE DRY SLOT ON THURSDAY. AS TIME GETS CLOSER...THESE
CHANCES WILL NEED TO BE FURTHER REFINED WITH INCREASES AGAIN LIKELY.
WEDNESDAY STILL LOOKS RELATIVELY WARM BEING IN THE WARM CONVEYOR
BELT AND 850MB TEMPS UPWARDS OF 8-12C. MOST LOCATIONS SHOULD REACH
THE MID 50S TO MID 60S RANGE...WARMEST EAST WHERE PRECIPITATION
BEGINS LATER. COOLER WEATHER THEN ON TAP FOR THURSDAY WITH THE UPPER
TROUGH IN PLACE AND POSSIBLE PRECIPITATION. ALSO ADDED A MENTION OF
THUNDER TO NORTHEAST IOWA AND FAR SOUTHWEST WISCONSIN ON WEDNESDAY
WHERE BOTH THE 14.00Z GFS/ECMWF DEPICT SOME MUCAPE BUILDING UP.
AFTER THURSDAY...QUESTION IS HOW FAST THE UPPER LOW/TROUGH PUSHES
EAST. THE 14.00Z ECMWF/CANADIAN HAVE RIDGES AMPLIFYING ACROSS THE
WESTERN U.S. AND FROM NEW ENGLAND INTO QUEBEC...EFFECTIVELY BLOCKING
THE TROUGH FROM REALLY GOING ANYWHERE. THE 14.00Z GFS AND QUITE A
FEW OF ITS ENSEMBLE MEMBERS DO NOT HAVE AS MUCH RIDGING OVER NEW
ENGLAND AND QUEBEC...THUS ALLOWING THE TROUGH TO LIFT OUT. THINK
THIS LATTER SCENARIO IS TOO FAST AND THUS LEANING THE FORECAST MORE
TOWARDS THE CONSISTENT ECMWF/CANADIAN SOLUTIONS. THIS RESULTS IN
MAINTAINING COOL WEATHER WITH HIGHS IN THE LOW TO MID 50S ALONG WITH
LOW CHANCES OF PRECIPITATION THROUGH SATURDAY. REASON FOR THE LOW
PRECIPITATION CHANCES...GENERALLY 20-30...IS A COMBINATION OF MODEL
UNCERTAINTY ON THE EVOLUTION/TRACK OF THE UPPER LOW/TROUGH AS WELL
AS SUGGESTIONS OF THE UPPER LOW/TROUGH FILLING WITH TIME.
&&
.AVIATION...THROUGH 06Z MONDAY
1147 PM CDT SAT OCT 13 2012
AREA OF SHOWERS WITH A FEW THUNDERSTORMS ADVANCING NORTHEAST
TOWARD THE AREA OUT OF IOWA LATE THIS EVENING. EXPECT THIS WILL
CONTINUE INTO THE AREA AND POSSIBLY EXPAND AS THE FRONTOGENESIS
IN THE 700-500 MB LAYER STRENGTHENS THROUGH THE NIGHT AND THERE
WILL BE A CONTINUED UP GLIDE OF 2 TO 5 UBAR/S ON THE 300K
ISENTROPIC SURFACE. THE 14.00Z NAM SUGGESTS THE MU CAPE WILL STAY
TO THE SOUTH SO WILL NOT SHOW ANY THUNDER. THE CONCERN IS WHERE
IS THE BACK EDGE OF THE RAIN GOING TO SET UP. THE NAM SUGGESTS
THAT THE RAIN WILL MAKE IT INTO KLSE BUT NOT KRST. FOR THE MOST
PART...THE LAST FEW RUNS OF THE HRRR AGREE WITH THIS TREND BUT THE
14.01Z DOES SUGGEST THE POTENTIAL FOR SOME SHOWERS TO GET TO KRST
BEFORE 12Z. THUS PLAN TO BRING THE SHOWERS INTO KLSE OVERNIGHT AND
CONTINUE THEM THROUGH MUCH OF SUNDAY MORNING AND WILL SHOW A SHORT
PERIOD LATE TONIGHT WHEN THE SHOWERS COULD POSSIBLY GET INTO KRST.
NOT EXPECTING CEILINGS TO DO MUCH OVERNIGHT AND REMAIN IFR AT BOTH
TAF SITES. FORECAST SOUNDINGS DO NOT SHOW MUCH IMPROVEMENT
OCCURRING UNTIL SUNDAY AFTERNOON WHEN THE LOW LEVEL INVERSION
STARTS TO MIX OUT. LIFTED THE CEILINGS FROM IFR TO VFR BY LATE
AFTERNOON AND EXPECT THERE WILL BE A PERIOD OF MVFR IN BETWEEN BUT
THIS CAN BE DETAILED WITH LATER FORECASTS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
258 AM CDT SUN OCT 14 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
UPDATE...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
259 AM CDT SUN OCT 14 2012
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
258 AM CDT SUN OCT 14 2012
MAIN FORECAST CONCERNS ARE ON PRECIPITATION TODAY AS WELL AS
PRECIPITATION CHANCES FOR MONDAY NIGHT THROUGH TUESDAY NIGHT.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING BUILDING UP ACROSS THE WESTERN U.S. INTO BRITISH
COLUMBIA...A NORTHERN STREAM TROUGH OVER SOUTH CENTRAL CANADA AND
NORTH DAKOTA...AND AN UPPER LOW NEAR TOPEKA KS. ALSO OF INTEREST IS
120KT JET STREAK AROUND 200MB OVER LAKE SUPERIOR ACCORDING TO THE
RAP. THE COMBINATION OF UPPER DIVERGENCE IN THE RIGHT ENTRANCE
REGION OF THIS UPPER JET...THE PRESENCE OF LOW TO MID LEVEL
FRONTOGENESIS OVER THE SOUTHERN HALF OF THE FORECAST AREA SEEN JUST
BY CONVERGENCE IN 850MB PROFILER AND VWP DATA...AND PLENTIFUL
MOISTURE NOTED BY GOES PRECIPITABLE WATER VALUES OF 1.4 INCHES IN
THE SAME PLACE IS RESULTING IN A BAND OF SHOWERS AND EMBEDDED
THUNDERSTORMS. BACK EDGE OF THIS PRECIPITATION ALONG A LINE
EXTENDED FROM CHARLES CITY TO VIROQUA AND WISCONSIN DELLS.
NORTHWEST OF THIS LINE...PRECIPITABLE WATER VALUES DROP OFF
DRAMATICALLY... DOWN TO AROUND 0.75 INCH IN WEST CENTRAL MINNESOTA.
IN FACT...SATELLITE IMAGERY DEPICTS CLEARING OVER WESTERN
MINNESOTA AND THE EASTERN DAKOTAS. AT THE SURFACE...A 998MB LOW
WAS PRESENT IN SOUTHWEST IOWA WITH A WARM FRONT EXTENDING
NORTHEAST INTO SOUTHWEST WISCONSIN.
TODAY...MODELS DEPICT THE NORTHERN STREAM TROUGH OVER SOUTH CENTRAL
CANADA DROPPING DOWN INTO MINNESOTA AND IOWA...WHICH HELPS TO KICK
THE UPPER LOW NEAR TOPEKA NORTHEASTWARD. BY 00Z...MODELS HAVE THE
UPPER LOW AND THE ASSOCIATED SURFACE LOW IN CENTRAL LAKE MICHIGAN...
SLIGHTLY SLOWER THAN SEEN YESTERDAY. THE FORECAST AREA...IN
PARTICULAR THE SOUTHEAST HALF...WILL STAY IN THE DEFORMATION ON THE
NORTHWEST SIDE OF THE LOW TRACK WHICH IS QUITE FAVORABLE FOR
PRECIPITATION. IN FACT...THE CURRENT BAND OF SHOWERS AND EMBEDDED
THUNDERSTORMS SHOULD INTENSIFY THIS MORNING AS DPVA INCREASES FROM
THE APPROACHING UPPER LOW. FRONTOGENESIS FIELDS ALSO STRENGTHEN IN
RESPONSE TO THE INCREASING DPVA. PRECIPITATION WILL TAPER OFF IN THE
AFTERNOON WEST TO EAST AS THE UPPER JET...FRONTOGENESIS AND THE
OVERALL SYSTEM MOVE EAST AWAY FROM THE AREA. DECENT AMOUNT OF QPF
EXPECTED TODAY IN SOUTHEAST SECTIONS OF THE FORECAST AREA GIVEN
THE STRONG FORCING THIS MORNING AND PRECIPITABLE WATER VALUES NEAR
1.5 INCHES. BLEND OF GUIDANCE SUGGESTS UPWARDS OF 1 INCH BETWEEN
12-18Z FROM OELWEIN TO PRAIRIE DU CHIEN AND BOSCOBEL. ALTHOUGH
CLEARING IS NOT TOO FAR AWAY...OVER WESTERN MINNESOTA...14.00Z
NAM/14.03Z RAP SOUNDINGS SUGGEST IT WILL TAKE ITS TIME SHIFTING
EAST AS MOISTURE STAYS TRAPPED BELOW A SUBSIDENCE INVERSION AT
5000 FT. WILL PLAY THIS MORE PESSIMISTIC ROUTE COMPARED TO THE
QUICKER CLEARING GFS GIVEN THAT CLIMATOLOGICALLY CLOUD COVER TENDS
TO HOLD AROUND LONGER. WITH PLENTY OF CLOUDS AND 850MB TEMPS
FALLING FROM 8-12C AT 12Z TO 2-4C AT 00Z...ANTICIPATE TEMPERATURES
TO NOT RISE MUCH. IN FACT...READINGS COULD FALL...ESPECIALLY OVER
THE EASTERN TWO THIRDS OF THE AREA WHICH STAND NO CHANCE OF SEEING
SUN.
TONIGHT AND MONDAY...RAPID EVOLUTION OF THE UPPER AIR PATTERN IS
FORECAST OVER THE AREA DURING THIS TIME. THE NORTHERN STREAM TROUGH
DROPPING INTO IOWA AT 00Z IS PROGGED TO DIG INTO ILLINOIS BY 12Z...
THEN RIDGING SEEN OVER BRITISH COLUMBIA RIGHT NOW EXPECTED TO SHIFT
OVER THE AREA BY 00Z TUESDAY. NOT ANTICIPATING ANY PRECIPITATION
WITH THE NORTHERN STREAM TROUGH...NOR WITH THE WARM ADVECTION
ACCOMPANYING THE UPPER RIDGE BUILDING IN ON MONDAY...AS TOO MUCH
SUBSIDENCE AND DRYING FLOWS IN BEHIND THE CURRENT STORM SYSTEM.
WOULD HAVE SOME CONCERN ABOUT VALLEY FOG TONIGHT WITH SKIES LIKELY
TO CLEAR FROM WEST TO EAST AND LINGERING MOISTURE FROM TODAYS RAIN.
HOWEVER...THERE IS TOO MUCH OF A NORTHWEST BREEZE BETWEEN THE
DEPARTING STORM SYSTEM AND A SURFACE HIGH PRESSURE RIDGE BUILDING
INTO WESTERN MINNESOTA BY 12Z. THIS BREEZE SHOULD HELP KEEP
TEMPERATURES FROM DROPPING TOO MUCH AS WELL. GENERALLY FOLLOWED A
BLEND OF GUIDANCE FOR LOWS. WITH THE PASSAGE OF THE SURFACE RIDGE ON
MONDAY...MORE SUN AND 850MB TEMPS CLIMBING TO 4C EAST TO 7C WEST BY
00Z...SHOULD SEE A WARMER DAY. THE AFOREMENTIONED LATE IN THE DAY
850MB TEMPS SUPPORT HIGHS IN THE MID 50S TO LOWER 60S. THESE ARE
LOWER THAN PREVIOUSLY FORECAST BECAUSE MODELS ARE SLOWER IN BRINGING
THE WARMER AIR IN.
MONDAY NIGHT AND TUESDAY...MODELS DEPICT A SHORTWAVE TROUGH OVER
NORTH DAKOTA AT 00Z TUESDAY...PARTLY RESPONSIBLE FOR THE UPPER RIDGE
THAT MOVED INTO THE AREA ON MONDAY...MOVING QUICKLY TO THE EAST
AND PERHAPS EVEN WEAKENING. THIS WEAKENING MAKES SENSE AS THERE IS A
MUCH MORE IMPRESSIVE AND POTENT UPPER TROUGH DIGGING DOWN INTO THE
NORTHERN U.S. ROCKIES. QUESTION IS IF ANY PRECIPITATION WILL OCCUR
WITH THAT SHORTWAVE TROUGH THAT TRACKS TO OUR NORTH. 14.00Z NAM
KEEPS ALL PRECIPITATION WELL TO THE NORTH...FROM NORTHERN MINNESOTA
INTO THE U.P.. THE 14.00Z GFS SHOWS SOME PRECIP CROSSING THE
NORTHERN SECTIONS OF THE FORECAST AREA...THOUGH VARIOUS ISENTROPIC
LIFT LEVELS FROM 290-310K SHOW VERY LITTLE LIFT OCCURRING WITH IT.
PLUS...THE PRECIPITATION IS FALLING OUT OF A 9000 FT CEILING. ALL
MODELS HAVE CERTAINLY TRENDED DRIER AND LESS IMPRESSIVE WITH THE
SHORTWAVE TROUGH. HAVE DECIDED TO MAINTAIN SOME 20 PERCENT
CHANCES...MAINLY ON TUESDAY NORTHEAST OF I-94. IDEA HERE BEING THAT
IT MAY TAKE AWHILE TO SATURATE THE LOWER LEVELS WITH THE WARM
ADVECTION TO ALLOW PRECIPITATION TO OCCUR. ALTHOUGH WE MAY GET
LITTLE PRECIPITATION OVERALL WITH THE SHORTWAVE TROUGH...THERE IS
DEFINITE WARMING COMING INTO THE FORECAST AREA WITH IT. 850MB TEMPS
CLIMB TO AT LEAST 10-14C BY 18Z TUESDAY. WITH POTENTIAL FOR ANY WARM
ADVECTION MID CLOUDS TO CLEAR OUT ON TUESDAY...COULD SEE DECENT
MIXING. AS SUCH...HAVE BUMPED UP TEMPERATURES ABOUT 5 DEGREES TO
COME IN BETTER ALIGNMENT WITH GUIDANCE. MONDAY NIGHT STILL LOOKS
RELATIVELY MILD THANKS TO THE INCREASE IN MID CLOUDS AND SOME
SOUTHERLY BREEZE.
TUESDAY NIGHT...THE POTENT TROUGH DIGGING INTO THE NORTHERN ROCKIES
ON TUESDAY IS PROGGED TO DIVE DOWN INTO THE DAKOTAS. IMPRESSIVE
WINDY AND COLD ADVECTION SETUP BEHIND IT WITH MODEL PROGS OF A 980S
MB LOW NEAR LAKE WINNIPEG AND 1025-1030MB SURFACE HIGH OVER THE
NORTHWESTERN U.S.. FOR OUR AREA...WE ARE IN THE WARM ADVECTION SETUP
AHEAD OF THE LOW WITH INDICATIONS OF 500MB HEIGHTS FALLING AFTER
MIDNIGHT. THEREFORE...ANTICIPATING SOME MID AND HIGH CLOUDS
SPREADING WEST TO EAST AGAIN...LIKE MONDAY NIGHT. LOWER LEVEL
SATURATION BECOMES AN ISSUE FOR ANY PRECIPITATION TO FALL OUT OF
THESE CLOUDS. BOTH THE 14.00Z GFS AND NAM SUGGEST SOME LIGHT QPF CAN
FALL ACROSS NORTHWEST SECTIONS OF THE FORECAST AREA BETWEEN 06-12Z
WEDNESDAY...WHICH HAVE BEEN ACKNOWLEDGED WITH A 15-20 PERCENT
CHANCE. OTHERWISE...DRY CONDITIONS WITH A LIGHT SOUTHERLY BREEZE
WILL BE THE RULE. COMBINATION OF THAT SOUTHERLY BREEZE AND
CLOUDS...ALONG WITH DEWPOINTS WHICH SHOULD BE UP IN THE 40S IS
EXPECTED TO HELP HOLD LOWS UP IN THE MID 40S TO LOW 50S.
.LONG TERM...WEDNESDAY THROUGH SATURDAY NIGHT
258 AM CDT SUN OCT 14 2012
MAIN STORY FOR THE EXTENDED REVOLVES AROUND THAT POTENT UPPER TROUGH
DROPPING DOWN INTO THE DAKOTAS TUESDAY NIGHT. 14.00Z
ECMWF/GFS/CANADIAN AND GFS ENSEMBLES ALL SHOW THIS TROUGH DIGGING
INTO THE UPPER MISSISSIPPI RIVER VALLEY AND EASTERN MISSOURI RIVER V
REGIONS BY 12Z THURSDAY. AS THIS TROUGH DIGS...IT GRADUALLY PULLS UP
MORE AND MORE MOISTURE FROM THE GULF OF MEXICO. THEREFORE...
PRECIPITATION WITH IT SEEMS LIKELY. BIGGEST PROBLEM IS EVOLUTION OF
THE VARIOUS WARM AND COLD CONVEYOR BELTS AS THIS SYSTEM WRAPS
UP...WITH POTENTIAL OF A DRY SLOT COMING AROUND THE UPPER LOW TOO.
FOLLOWED THE CONSENSUS APPROACH FOR NOW WHICH INCREASES CHANCES TO
AROUND 50 ON WEDNESDAY...WITH THE EXPECTED WARM CONVEYOR BELT...
LOWER 30-40 PERCENT CHANCES ON WEDNESDAY NIGHT WITH A POSSIBLE DRY
SLOT...THEN 50 PERCENT CHANCES OVER MINNESOTA WITH THE COLD CONVEYOR
BELT TO 30 PERCENT CHANCES IN SOUTHEAST SECTIONS OF THE FORECAST
AREA WITH POSSIBLE DRY SLOT ON THURSDAY. AS TIME GETS CLOSER...THESE
CHANCES WILL NEED TO BE FURTHER REFINED WITH INCREASES AGAIN LIKELY.
WEDNESDAY STILL LOOKS RELATIVELY WARM BEING IN THE WARM CONVEYOR
BELT AND 850MB TEMPS UPWARDS OF 8-12C. MOST LOCATIONS SHOULD REACH
THE MID 50S TO MID 60S RANGE...WARMEST EAST WHERE PRECIPITATION
BEGINS LATER. COOLER WEATHER THEN ON TAP FOR THURSDAY WITH THE UPPER
TROUGH IN PLACE AND POSSIBLE PRECIPITATION. ALSO ADDED A MENTION OF
THUNDER TO NORTHEAST IOWA AND FAR SOUTHWEST WISCONSIN ON WEDNESDAY
WHERE BOTH THE 14.00Z GFS/ECMWF DEPICT SOME MUCAPE BUILDING UP.
AFTER THURSDAY...QUESTION IS HOW FAST THE UPPER LOW/TROUGH PUSHES
EAST. THE 14.00Z ECMWF/CANADIAN HAVE RIDGES AMPLIFYING ACROSS THE
WESTERN U.S. AND FROM NEW ENGLAND INTO QUEBEC...EFFECTIVELY BLOCKING
THE TROUGH FROM REALLY GOING ANYWHERE. THE 14.00Z GFS AND QUITE A
FEW OF ITS ENSEMBLE MEMBERS DO NOT HAVE AS MUCH RIDGING OVER NEW
ENGLAND AND QUEBEC...THUS ALLOWING THE TROUGH TO LIFT OUT. THINK
THIS LATTER SCENARIO IS TOO FAST AND THUS LEANING THE FORECAST MORE
TOWARDS THE CONSISTENT ECMWF/CANADIAN SOLUTIONS. THIS RESULTS IN
MAINTAINING COOL WEATHER WITH HIGHS IN THE LOW TO MID 50S ALONG WITH
LOW CHANCES OF PRECIPITATION THROUGH SATURDAY. REASON FOR THE LOW
PRECIPITATION CHANCES...GENERALLY 20-30...IS A COMBINATION OF MODEL
UNCERTAINTY ON THE EVOLUTION/TRACK OF THE UPPER LOW/TROUGH AS WELL
AS SUGGESTIONS OF THE UPPER LOW/TROUGH FILLING WITH TIME.
&&
.AVIATION...THROUGH 06Z MONDAY
1147 PM CDT SAT OCT 13 2012
AREA OF SHOWERS WITH A FEW THUNDERSTORMS ADVANCING NORTHEAST
TOWARD THE AREA OUT OF IOWA LATE THIS EVENING. EXPECT THIS WILL
CONTINUE INTO THE AREA AND POSSIBLY EXPAND AS THE FRONTOGENESIS
IN THE 700-500 MB LAYER STRENGTHENS THROUGH THE NIGHT AND THERE
WILL BE A CONTINUED UP GLIDE OF 2 TO 5 UBAR/S ON THE 300K
ISENTROPIC SURFACE. THE 14.00Z NAM SUGGESTS THE MU CAPE WILL STAY
TO THE SOUTH SO WILL NOT SHOW ANY THUNDER. THE CONCERN IS WHERE
IS THE BACK EDGE OF THE RAIN GOING TO SET UP. THE NAM SUGGESTS
THAT THE RAIN WILL MAKE IT INTO KLSE BUT NOT KRST. FOR THE MOST
PART...THE LAST FEW RUNS OF THE HRRR AGREE WITH THIS TREND BUT THE
14.01Z DOES SUGGEST THE POTENTIAL FOR SOME SHOWERS TO GET TO KRST
BEFORE 12Z. THUS PLAN TO BRING THE SHOWERS INTO KLSE OVERNIGHT AND
CONTINUE THEM THROUGH MUCH OF SUNDAY MORNING AND WILL SHOW A SHORT
PERIOD LATE TONIGHT WHEN THE SHOWERS COULD POSSIBLY GET INTO KRST.
NOT EXPECTING CEILINGS TO DO MUCH OVERNIGHT AND REMAIN IFR AT BOTH
TAF SITES. FORECAST SOUNDINGS DO NOT SHOW MUCH IMPROVEMENT
OCCURRING UNTIL SUNDAY AFTERNOON WHEN THE LOW LEVEL INVERSION
STARTS TO MIX OUT. LIFTED THE CEILINGS FROM IFR TO VFR BY LATE
AFTERNOON AND EXPECT THERE WILL BE A PERIOD OF MVFR IN BETWEEN BUT
THIS CAN BE DETAILED WITH LATER FORECASTS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
258 AM CDT SUN OCT 14 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
145 AM EDT TUE OCT 16 2012
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 414 PM EDT MON OCT 15 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH EAST
OF LAKE HURON LEAVING MAINLY ZONAL FLOW TO THE WEST FROM THE PAC NW TO
THE UPPER MS VALLEY. AN UPSTREAM SHORTWAVE TROUGH WAS MOVING FROM
THE NRN ROCKIES INTO THE NRN PLAINS. AT THE SFC...A RIDGE WAS
BUILDING ACROSS WRN LAKE SUPERIOR AND W UPPER MI. SRLY WINDS WERE
INCREASING OVER MN AHEAD OF A TROUGH FROM SRN MANITOBA INTO THE
CNTRL DAKOTAS. VIS LOOP SHOWED CLEARING SKIES OVER THE W HALF OF
UPPER MI. HOWEVER...HIGH CLOUDS SUPPORTED BY WAA AHEAD OF THE TROUGH
WERE QUICKLY STREAMING FROM MN INTO WRN WI. SOME LIGHT RAIN HAD ALSO
DEVELOPED FROM NEAR WINNIPEG INTO NW MN WITH WAA/ISENTROPIC LIFT
AHEAD OF THE TROUGH.
THE MODELS WERE IN GOOD AGREEMENT WITH THE MID LEVEL TROUGH DIGGING
FROM THE NRN PLAINS INTO THE UPPER MS VALLEY TONIGHT INTO TUE.
EXPECT THE AREA OF RAIN TO THE WEST TO EXPAND LATE TONIGHT AND
SPREAD INTO THE WRN CWA AS 925-850 MB MOISTURE TRANSPORT AND
295-300K ISENTROPIC LIFT INCREASE. AS THE 850-700 MB WARM FRONT
MOVES THROUGH THE AREA TUE...PCPN WILL SPREAD ACROSS THE CWA.
ALTHOUGH LIKELY-CATEGORICAL POPS WERE WARRANTED...THE HEAVIER PCPN
(INTO THE 0.25 TO 0.50 RANGE) IS EXPECTED MAINLY ACROSS THE NORTH
AND EAST FROM THE KEWEENAW INTO THE ERN CWA WHERE THE STRONGEST LIFT
AHEAD OF THE 850 MB WARM FRONT IS PROGGED....PER NAM/REGIONAL-GEM.
MODELS TIMING HAS ALSO BEEN CONSISTENT WITH THE PCPN ENDING OVER THE
WEST BY EARLY AFTERNOON AND OVER THE EAST LATE.
TEMPS WILL DROP INTO THE LOW TO MID 30S THIS EVENING BEFORE THE
CLOUDS THICKEN AND SRLY WINDS INCREASE RESULTING IN SLOWLY CLIMBING
TEMPS OVERNIGHT. AS THE PCPN ENDS TUE AFTERNOON...WAA WILL ALSO DRAW
ENOUGH WARM AIR INTO THE REGION TO PUSH MAX READINGS INTO UPPER 50S
WEST WHILE TEMPS LINGER AROUND 50 OVER THE EAST.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 414 PM EDT MON OCT 15 2012
MID WEEK WILL REMAIN UNSETTLED AS A DEEP UPPER TROUGH OVER THE
CANADIAN PRAIRIE PROVINCES CLOSES OFF OVER THE UPPER MIDWEST/GREAT
LAKES. THIS WILL ALLOW FOR PRECIPITATION CHANCES THROUGH THURSDAY
WITH AT OR SLIGHTLY BELOW NORMAL TEMPERATURES.
FOR THE DETAILS...EXPECT THE WARM ADVECTION/ISENTROPIC LIFT PCPN
ASSOCIATED WITH THE 850MB WARM FRONT TO MOVE EAST OF THE FORECAST
AREA TUESDAY NIGHT...LEADING TO THE AREA BEING IN THE WARM SECTOR
AHEAD OF THE DEEP SFC LOW AND OCCLUDED FRONT EXTENDING FROM LAKE
WINNIPEG INTO THE PLAINS. WILL MAINTAIN LOW CHANCE POPS IN THE
EVENING EAST OF MARQUETTE DUE TO CONTINUED WEAK ISENTROPIC LIFT AND
MID LVL Q-VECT CONVERGENCE. LOW CLOUDS/FOG WILL REMAIN A CONCERN
OVERNIGHT DUE TO CLEARING SKIES AND LEFTOVER LOW LEVEL MOISTURE FROM
AFTN/EVENING RAINFALL AND AS SUCH HAVE MAINTAINED FOG CHANCES.
THE OCCLUDED FRONT WILL MOVE EAST ON WEDNESDAY AS THE UPPER SYSTEM
CLOSES OFF. EXPECT A BAND OF SHOWERS TO MOVE INTO THE WESTERN U.P.
WEDNESDAY AFTERNOON ASSOCIATED WITH PRECIPITABLE WATER VALUES IN
EXCESS OF 1 INCH AND MID LVL Q-VECTOR CONVERGENCE. DUE TO THE LOW
CLOSING OFF...THE BAND OF SHOWERS WILL ONLY SLOWLY MOVE EAST WED
AFTN/NIGHT. IN FACT...THERE WILL LIKELY BE A PROLONGED PERIOD OF
STEADY RAIN WED EVENING ACROSS UPPER MICHIGAN DUE TO THE ROTATION
AND TIGHTENING OF THE 850MB ISOTHERMS CONTRIBUTING TO INCREASED
FN/FS VECTOR CONVERGENCE IN THE TROWAL REGION. WILL THEREFORE
MAINTAIN LIKELY POPS ACROSS THE ENTIRE U.P. WED NIGHT.
TRICKY AND UNCERTAIN FORECAST FOR THURSDAY. THE ECMWF SUGGESTS THAT
MOST OF THE U.P. WILL BE DRY WITH THE COMMA HEAD MOISTURE/PCPN BACK
INTO MN AND NW WISCONSIN DUE TO THE UPPER LOW BEING FURTHER WEST
THAN THE GFS WHICH HAS THE UPPER LOW OVERHEAD. AM THINKING THAT THE
BEST CHANCES FOR PCPN WILL BE ACROSS THE WEST AND HAVE OPTED TO
MAINTAIN HIGH CHANCE POPS FOR THAT AREA. DUE TO SIGNIFICANT
UNCERTAINTY...WILL STILL NEED TO MAINTAIN CHANCE POPS TO THE EAST.
CONFIDENCE IN THE EXTENDED FORECAST FOR FRIDAY-MONDAY STILL QUITE
LOW WITH DIFFERENCES BETWEEN THE ECWMF...GFS AND CANADIAN IN HOW
FAST THE GREAT LAKES CLOSED LOW EJECTS TO THE NORTHEAST. TEND TO
BELIEVE THE SLOWER ECMWF SOLUTION WHICH WOULD KEEP A DRIER FORECAST
FOR THE UPPER LAKES FOR THE WEEKEND DUE TO UPPER RIDGING HANGING ON
ACROSS THE UPPER MIDWEST. THE BELOW CONFIDENCE FORECAST NOT ONLY
APPLIES TO PRECIPITATION CHANCES...BUT ALSO TO TEMPERATURES AS THE
ECMWF WOULD BE WARMER COMPARED TO THE CLOUDY/COOL GFS.
WITH ALL OF THIS SAID...WILL TREND TOWARD THE 00Z AND 12Z ECMWF AND
LOWER POPS TO SLIGHT CHANCE OR LOW CHANCE POPS EACH DAY IN THE
EXTENDED. IN FACT IF THE 00Z ECMWF VERIFIES IT WILL END UP BEING A
DECENT WEEKEND. ON THE OTHER HAND...IF THE GFS VERIFIES IT COULD BE
MUCH WETTER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 130 AM EDT TUE OCT 16 2012
A TROUGH WILL MOVE TOWARD THE AREA LATE TONIGHT BRINGING THICKENING
CLOUDS AND THE POTENTIAL FOR SOME LIGHT RAIN LATE TONIGHT. EXPECT
RAIN WITH MVFR CIGS TO MOVE IN TUESDAY AT KCMX AND CONDITIONS TO
STAY VFR THROUGH THE PERIOD AT KSAW AND KIWD. THERE WILL BE SOME
LLWS AT TIMES AT ALL SITES.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 414 PM EDT MON OCT 15 2012
WINDS WILL CONTINUE TO DIMINISH THIS EVENING AS HIGH PRES BUILDS
INTO THE REGION. ANOTHER LOW PRESSURE TROUGH APPROACHING THE UPPER
GREAT LAKES LATE TONIGHT WILL RESULT IN SOUTH WINDS OF 15 TO 25 KT
WITH AREAS TO NEAR 30 KT OVER ERN LAKE SUPERIOR LATE TUE AFTERNOON
AND EVENING. A DEEPER LOW PRESSURE SYSTEM MOVING INTO THE UPPER GREAT LAKES
ON THURSDAY COULD CAUSE AN INCREASE IN ERLY WINDS TO 30 KT LATE WED
NIGHT INTO THURSDAY. OTHERWISE...WINDS IN THE VICINITY OF THE LOW
SHOULD GENERALLY REMAIN LESS THAN 20 KTS WEDNESDAY THROUGH FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...MRD
AVIATION...VOSS
MARINE...JLB
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
122 AM EDT TUE OCT 16 2012
.SYNOPSIS...
A COLD FRONT OVER FAR EASTERN PENNSYLVANIA THIS EVENING WILL EXIT
OFF THE MID ATLANTIC COAST OVERNIGHT. MAINLY DRY AND MILD WEATHER
WILL FOLLOW FOR THE MID-WEEK PERIOD. A DEEP UPPER LEVEL LOW WILL
DEVELOP OVER THE UPPER PLAINS AND MIDWEST OVER THE NEXT FEW DAYS.
THE DEEP LOW WILL THEN MOVE TO THE EAST AND PUSH A COLD FRONT
THROUGH LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
SFC COLD FRONT IS APPROACHING THE NEW JERSEY COAST...AND NW FLOW
IN THE LOWEST 5-6 KFT HAS SPREAD ACROSS ALL OF THE CWA IN ITS
WAKE. STRONG BACKING TO THE FLOW WAS SEEN ACROSS THE EASTERN
2/3RDS OF THE CWA /IN THE MID AND UPPER LEVELS/ AS A SHARPENING
UPPER TROUGH DRIFTS RIGHT OVERHEAD LATE TONIGHT.
LAST VESTIGES OF RAIN WAS BRUSHING SERN YORK AND LANCASTER
COUNTIES ATTM...IN ASSOCIATION WITH UVVEL BENEATH THE FAVORABLE
RIGHT ENTRANCE REGION OF STRONG UPPER JET. SOME PARTIAL CLEARING
WILL OCCUR ACROSS THE SUSQ VALLEY THANKS TO DEEPENING SUBSIDENCE
AS THE LEFT ENTRANCE REGION OF THE 115 KT UPPER JET DRAGS ACROSS
THAT REGION.
FURTHER WEST...STRONG MID LEVEL /700-500MB/ COLD ADVECTION AND A
POCKET OF STEEP 850-700 MB LAPSE RATES WAS SUPPORTING SCATTERED
LIGHT SHOWERS ACROSS THE WESTERN MTNS AND LAUREL HIGHLANDS.
LATEST HRRR GUIDANCE SHOWS THIS AREA OF SHOWERS DISSOLVING QUICKLY
OVER THE NEXT FW HOURS AND BECOMING CONFINED TO THE FAR NW ZONES
THROUGH ABOUT 06-07Z.
ADDITIONAL RAINFALL AMOUNTS IN ANY OF THESE AFOREMENTIONED AREAS OF
SHOWERS WILL BE 0.05 OR LESS.
THIS POCKET OF COLD AIR ALOFT WITH 700 MB TEMPS INITIALLY AROUND
-8C EARLY THIS EVENING...WILL GRADUALLY FILL/WARM BY 3-4C AS IT
CROSSES CENTRAL PENN...AND REACHES THE SUSQ VALLEY LATE TONIGHT.
OTHERWISE...SHALLOW MOISTURE TRAPPED BENEATH THE LOWERING
SUBSIDENCE INVERSION BASE WILL KEEP SKIES MOSTLY CLOUDY TO CLOUDY
ACROSS THE NRN AND WRN MTNS...WITH VARYING AMOUNTS OF STRATO CU
ACROSS THE SE HALF OF THE FCST AREA.
TEMPS ON TRACK TO ACHIEVE LOWS RIGHT AROUND NORMAL EARLY TUESDAY...
RANGING FROM THE M-U30S ACROSS THE NW...TO THE M40S IN THE SE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/...
ANY ISOLD SHRA IN THE NW SHOULD BE DONE AROUND SUNRISE TUES...SO
WILL KEEP POPS NIL AREA WIDE FOR THE DAYTIME. DAYTIME TEMPS WILL
REMAIN VERY CLOSE TO SEASONAL NORMALS...TOPPING OUT IN THE M50S-
M60S. RIDGE AXIS STILL OFF TO THE WEST IN THE MORNING...BUT
OVERHEAD LATE IN THE DAY...SO WINDS SHOULD BEGIN 8-10KTS AND COULD
INCREASE/GUST A LITTLE BUT THEN LIGHTEN UP - ESP IN THE W -
THROUGH THE AFTN. AN UNEVENTFUL BUT TYPICAL AUTUMN DAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
SFC HIGH PRESSURE RIDGE OVER THE REGION FOR MIDWEEK WITH WESTERLY
FLOW TURNING SW ALOFT AHEAD OF DEVELOPING TROUGH. SO DRY WEATHER
WILL PREVAIL TUE NIGHT INTO THU. CHILLY NIGHT TUE NIGHT WITH LOWS IN
THE 30S...BUT RETURN FLOW ON BACK SIDE OF HIGH WILL PUSH TEMPS
SLIGHTLY ABOVE NORMAL ON WED. MILDER NIGHT WED NIGHT...THEN
INCREASING CLOUD COVER WILL BRING SEASONAL TEMPS FOR THU.
TROUGH EDGES TOWARD PA LATE WEEK...WITH FRONT RUNNING OUT AHEAD OF
SYSTEM FOR THU NIGHT/FRI BRINGING BEST CHANCE FOR WIDESPREAD RAIN
THIS WEEK. EASTERN SECTIONS COULD SEE HIGHEST AMOUNTS...WITH QPF
AROUND 0.25 INCHES...POSS UP TO 0.75 INCHES ON EASTERN EDGE.
UNFORTUNATELY...MODELS REMAIN STEADFAST IN THEIR DIFFERENCES THIS
WEEKEND WITH GFS REMAINING WEAKER AND MORE PROGRESSIVE WHILE THE
ECMWF STICKS WITH A LARGER AND SLOWER MOVING LOW. SO FORECAST
CONTINUES TO TRY TO MITIGATE THESE DIFFERENCES INTO A COMPROMISE
SOLUTION. AFTER BEST RAIN CHANCES CENTERED ON FRIDAY...KEPT SCT
SHOWERS POSS INTO THE WEEKEND WITH DRYING TREND LATE. TEMPS DO
COOL OFF A BIT OVER THE WEEKEND INTO EARLY NEXT WEEK...BUT REMAIN
CLOSE TO SEASONAL AVERAGES.
&&
.AVIATION /05Z TUESDAY THROUGH SATURDAY/...
COLD FRONT CONTINUES TO PUSHES EASTWARD OVER NIGHT AS DOWNSLOPING
WESTERLY FLOW ADVECTS IN IT/S WAKE. THIS FLOW SHOULD PRODUCE A PARTIAL
CLEARING ACROSS THE SUSQ VALLEY. RESIDUAL LOW LVL MOISTURE
ASCENDING THE W MTNS WILL PRODUCE PERSISTENT MVFR STRATO-CU AT
BFD AND IFR AT JST OVERNIGHT. SREF DATA MAKES IT POSSIBLE THAT
LIFR COULD EVEN BE PRESENT AT JST BETWEEN 09-14Z.
WHERE SKIES REMAIN CLOUDY...ATMOS WILL REMAIN WELL MIXED AND FAVOR
FREQUENT WIND GUSTS TO NEAR 20KTS OVERNIGHT ACROSS THE W MTNS.
DOWNSLOPING FLOW EAST OF THE MTNS WILL RESULT IN BRKS IN THE
OVERCAST...SOME RAD COOLING AND LIGHTER WIND SPEEDS.
SOME EARLY LOW CIGS ARE POSSIBLE TO START TUESDAY AT JST OR BFD.
HOWEVER...HIGH PRES BUILDING INTO THE STATE SUPPORTS A HIGH
CONFIDENCE FCST OF VFR CONDS EVERYWHERE BY MIDDAY.
OUTLOOK...
WED...NO SIG WX EXPECTED.
THU...AM LOW CIGS POSSIBLE EAST. PM SHRA/LOW CIGS POSS...MAINLY BFD.
FRI...SHRA/LOW CIGS POSSIBLE...ESP EARLY.
SAT...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...DANGELO
LONG TERM...RXR
AVIATION...FITZGERALD/CERU
AREA FORECAST DISCUSSION
NWS SPOKANE WA
221 AM PDT Tue Oct 16 2012
.SYNOPSIS...Windy conditions with scattered rain and high mountain
snow showers will affect the region today. Wind gusts of 35 to 50 mph
will be likely through this evening over portions of the Inland
Northwest. A drier, more stable pattern is expected for Wednesday
and Thursday, before more precipitation chances enter late in the
week with cooler temperatures.
&&
.DISCUSSION...
...VERY WINDY CONDITIONS TODAY...
Today and tonight...The cold front continues to move southeast
across the forecast area this morning with the back edge just south
of the I-90 corridor as of 08Z. The main area of steady rain is
confined to Shoshone county but widely scattered showers are
popping up all across the area in the unstable post frontal air
mass. A few lightning strikes have been recorded across the extreme
northern Cascades and across southern BC. The cold pool aloft will
keep things unsettled enough for a slight chance of thunderstorms
through about 15Z before the best forcing moves east. Gusty winds
are starting to increase as the surface pressure gradient
strengthens between the deepening low over southern Alberta and high
pressure off the coast. The gradient is expected to max out late
this morning to early afternoon. The benchmark that will support a
high wind warning is at least a 24mb difference between Lethbridge,
Alberta (CYQL) and Yakima (KYKM) along with synoptic support from a
jet streak overhead. We will be just shy of the gradient and the jet
will sag to the south this afternoon. This likely means that we will
be seeing a high end wind advisory. There could possibly be one or
two of the windier sites breaking into high wind criteria but
widespread damaging winds are not expected with this system. It will
also be a fast mover, with the low sliding into the Canadian
Prairies by 00z, weakening the gradient. No changes made to the
ongoing wind advisory at this time.
Another concern will be snow levels for the east slopes of the
Cascades. Models are bringing the 850mb 0C line along the crest with
the NAM12 down to -1C this morning. Radar mosaic is showing some
evidence of a convergent zone. The HRRR model agrees, but shows the
plume drifting south along the crest into slightly warmer air.
Depending on the location and persistence of this feature, some of
the higher valleys could see some light snowfall accumulation. After
a relatively mild morning, due to strong mixing by gusty winds,
temperatures will not warm very much today as cold air advection
takes over. Expect chilly temperatures tonight with most of the
northern valleys dipping below the freezing mark. For other valley
locations, mid 30s will be common. /Kelch
Wednesday through Thursday...Latest models are in good agreement
for this period. A quite break will grace the region as a weak
but perceptible short wave ridge builds over the forecast area in
the wake of Tuesday`s unpleasantness. Residual breezy winds and
lingering showers over the Idaho Panhandle will decrease Wednesday
morning as surface high pressure settles over the region. Wednesday`s
highs will peak right around seasonal normal with generally partly
cloudy to mostly sunny skies. The quiet break will continue on
Thursday although the ridge axis will pass to the east of the
region and open the way for increasing high clouds as the next
weather system approaches. The retreat of the ridge axis will
allow some warm advection to begin on Thursday in the pre-frontal
southwest flow regime...promoting high temperatures once again
slightly above normal...but with sunshine filtered through
thickening clouds especially across the northern zones.
Thursday night and Friday...The GFS and ECMWF models advertise a
ridge breakdown and subsequent cold front passage either Thursday
night (GFS) or Friday (EC). Both models have stuck to their
respective timing differences over the last few runs. The driving
force of a 120-140kt jet over the Gulf Of Alaska associated with
this wave suggest the faster GFS may be the best solution to work
with. Forecast will be based upon this reasoning...which yields
high pops over much of the forecast area Thursday night and into
Friday morning as a strong fetch of precipitable water enhances
along the cold front with good and well defined jet divergence and
differential PVA. High temperatures Friday are low
confidence...with the current forecast reflecting an assumption
of a morning precipitation threat followed by good afternoon
adiabatic mixing promoting high temperatures above average...but
if the EC is correct then highs may top out closer to average. In
any event...after the relatively benign conditions of Wednesday
and Thursday...there is high confidence that Friday will bring a
change to this pattern.
Friday night through Monday...Things get rather messy and
uncertain during this period with respect to timing multiple minor
waves and fronts in a much more progressive...cooler and wet
pattern. Where certainty is higher is the overall pattern
reflected by all the latest models featuring a cool zonal or
moderately cold troffy flow regime with the storm track to the
south of the forecast area. This argues for a broad brush approach
featuring a chance of valley rain and mountain snow each day
through the weekend and early next week...with the added
possibility of some overnight non-accumulating snow flakes down
to the valley and basin floors if any particular disturbance rides
through during the overnight or early morning hours. The deep
basin in the lee of the Cascades will probably miss out on any
significant precipitation given the rain shadow promoting mean
westerly flow. During this period the mountains above 4000 to 5000 feet
are likely to receive their first significant snow
accumulations...slowly building up to three to seven inches
through the weekend. Thus...confidence is high for a raw...breezy
and occasionally wet regime during this period...although
confidence is low regarding timing of any of the expected
transient focusing mechanisms and fronts. /Fugazzi
&&
.AVIATION...
06Z TAFS: The mid level cold front pushed east of all the
terminals this evening with stratiform rainfall transitioning to
convective showers. The atmosphere will begin to destabilize
through the night as the upper level trough pushes over the
region. This may result in some showers developing into
thunderstorms, but confidence is too low to include at any of the
taf sites. Moist upslope flow into KGEG, KSFF, KCOE and at KPUW
will result in some low stratus before drier air aloft begins to
clear skies out and improve conditions. The surface cold front
will move east of the Cascades over the next few hours with winds
beginning to gust out of the west and southwest by the early
morning hours and intensifying by the afternoon on Tuesday. Until
the surface front pushes through, expect some low level wind shear
at all terminals tonight. /SVH
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 56 37 54 37 60 43 / 30 10 0 0 10 60
Coeur d`Alene 55 34 53 33 60 40 / 50 10 0 0 10 60
Pullman 57 31 53 36 62 42 / 70 10 0 0 10 60
Lewiston 63 39 58 40 68 47 / 70 10 0 0 10 50
Colville 60 29 57 34 60 36 / 30 10 10 0 10 60
Sandpoint 53 33 52 32 57 39 / 70 10 10 0 10 60
Kellogg 50 35 48 32 56 39 / 90 20 10 0 10 70
Moses Lake 62 34 60 37 64 42 / 10 0 0 0 10 20
Wenatchee 58 40 57 39 65 45 / 10 0 0 0 10 30
Omak 61 33 59 37 62 38 / 10 0 0 10 10 60
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Wind Advisory until 8 PM PDT this evening for Coeur d`Alene Area-
Idaho Palouse-Lewiston Area.
WA...Wind Advisory until 8 PM PDT this evening for Lower Garfield and
Asotin Counties-Moses Lake Area-Spokane Area-Upper Columbia
Basin-Washington Palouse-Waterville Plateau-Wenatchee Area.
&&
$$
AREA FORECAST DISCUSSION
NWS MIAMI FL
939 AM EDT TUE OCT 16 2012
.UPDATE...
THE MORNING SURFACE ANALYSIS SHOWED A COLD FRONT EXTENDING
SOUTHWEST ACROSS THE FLORIDA PENINSULA FROM AROUND DAYTONA BEACH
TO JUST NORTH OF TAMPA. PLENTY OF DRY AIR WITH DEWPOINTS IN THE
LOWER 50S HAS ALREADY BEGUN TO SPREAD SOUTH INTO NORTHERN FLORIDA
IN ITS WAKE EARLY THIS MORNING. FARTHER SOUTH AHEAD OF THIS
BOUNDARY...A DECENT AMOUNT OF LOW-LEVEL MOISTURE WITH DEWPOINTS
REMAINING IN THE LOWER 70S WILL BE ANTICIPATED TODAY. THE MORNING
UPPER AIR SOUNDING IN MIAMI REFLECTED THIS MOISTURE UP TO AROUND
10 KFT OR 700 MB...THEN VERY DRY ABOVE THIS POINT. LOW-LEVEL WIND
PROFILE SHOWED NNE FLOW. AS A RESULT...THE LATEST HRRR AND WRF
MODEL REFLECTIVITIES INDICATE THE BEST CHANCE FOR MAINLY ISOLATED
SHOWERS LATER THIS AFTERNOON AND EVENING ACROSS THE SOUTHERN
EXTENT OF THE FL PENINSULA TODAY. FOR THE MORNING UPDATE...WE WILL
SLIGHTLY INCREASE THE AFTERNOON RAINFALL CHANCES OVER THESE SRN
AREAS AND CONTINUE THEM INTO THE EARLY EVENING HOURS.
OTHERWISE...THE PREVIOUS FORECAST PACKAGE REMAINS ON TRACK. 85/AG
&&
.PREV DISCUSSION... /ISSUED 727 AM EDT TUE OCT 16 2012/
AVIATION...
VFR CONDITIONS EXPECTED THROUGH THE PERIOD. A FEW SHRA POSSIBLE THIS
AFTERNOON MAINLY OVER THE INTERIOR WITH STEERING FLOW TO THE SOUTH.
LATEST HIGH RESOLUTION SHORT TERM GUIDANCE SUGGESTS THE DEVELOPMENT
WILL BE LATE AND MOSTLY FROM BROWARD COUNTY AND TO THE SOUTH SO
PLACED VCSH IN FOR THOSE TERMINALS AND REMOVED FROM THE KAPF TAF.
OFFSHORE LIGHT WIND FLOW ALONG BOTH COASTS THIS MORNING WILL BECOME
ONSHORE ALONG THE E CST AFT 15-16Z AND AFT 17-18Z AT KAPF AND THEN
OFFSHORE ONCE AGAIN THIS EVENING. /KOB
PREV DISCUSSION... /ISSUED 351 AM EDT TUE OCT 16 2012/
SHORT TERM (TODAY-THURSDAY)...
E COAST UPPER TROUGH LIFTS TO THE NE PULLING HURRICANE RAFAEL NORTH
-WARD WHILE THE ASSOCIATED COLD FRONT CURRENTLY OVER N FLA...SLOWLY
MOVES SOUTHWARD AS THE UPPER FLOW BECOMES ZONAL. BUT OVERNIGHT AND
INTO EARLY WEDNESDAY MORNING ANOTHER SHORT WAVE DIVES INTO THE SE
U.S. AND LIFTS NE BUT THE FRONT LIMPS INTO S FLA BY WED MORNING
.POSSIBLY STALLING AND WASHING OUT. HIGH PRESSURE THEN BUILDS OVER
THE EASTERN U.S. THURSDAY. PLENTY OF DRY AIR MOVING OVER S FLA BUT
ENOUGH MOISTURE IN PLACE TO TRIGGER SHOWER ACTIVITY THIS AFTERNOON
ACROSS MAINLY THE EASTERN HALF OF THE S FLA PENINSULA. ON WEDNESDAY
.WITH THE STALLING/DISSIPATING BOUNDARY AND POSSIBLE INFLUENCE OF
THE SHORT WAVE CROSSING ACROSS N FLA...THERE MAY BE A CHANCE OF
SHOWERS AND SOME THUNDERSTORMS ACROSS THE AREA WITH THE BETTER
CHANCE OF PRECIPITATION INTERIOR AND E DUE TO WESTERLY STEERING
FLOW. ON THURSDAY...SOME DRIER AIR MOVES OVER S FLA AGAIN AND
WITH A MINOR DECREASE IN POPS.
MIAMI BEACH HAD SOME COASTAL FLOODING ON MONDAY WITH SOME MINOR
INUNDATION OF SOME ROADWAYS DURING HIGH TIDE. WITH WATER LEVELS
STILL RUNNING A BIT ABOVE NORMAL...DURING THE HIGH TIDE CYCLE TODAY
.WHICH IS BETWEEN 9 AND 10 AM...SOME MINOR FLOODING MAY OCCUR
AGAIN. WITH DECREASING WINDS AND WITH TIDES RETURNING TO NORMAL
.THIS POTENTIAL FLOODING AT MIAMI BEACH WILL DIMINISH THROUGH THE
WEEK. LITTLE IN THE WAY OF ADDITION RAINFALL IS EXPECTED TODAY BUT A
POTENTIAL OF HEAVIER RAINFALL ON WEDNESDAY THAT COULD BECOME
CONCENTRATED AND THE ADDITIONAL RAINFALL COULD RESULT IN ADDITIONAL
FLOODING OR STANDING WATER CONCERNS. SOMETHING TO WATCH.
LONG TERM (FRIDAY-MONDAY)...
A STRONG CLOSED MID/UPPER LOW DIVES INTO THE GREAT LAKES REGION
FRIDAY AND SATURDAY THEN LIFTS NE INTO E CANADA AS A HIGH PRESSURE
RIDGE MOVES EASTWARD AND OVER THE E U.S. BY EARLY NEXT WEEK. THE
ASSOCIATED COLD FRONT...BASED ON GFS/ECMWF COMPARISON...APPEARS TO
NOT NEAR S FLA. SO...MOISTURE REMAINS IN PLACE THROUGH THE PERIOD
WITH WARM, HUMID CONDITIONS PREVAILING THROUGH THE FORECAST PERIOD
ALONG WITH A DAILY CHANCE OF SHOWERS/TSTORMS. WITH WESTERLY STEERING
WINDS THE INTERIOR AND E WILL BE FAVORED.
MARINE...ATLC SEAS OF 2 TO 4 FEET...ESPECIALLY OFF OF PALM BEACH
COUNTY...THROUGH TONIGHT THEN 2 TO 3 FEET ALL ATLC WATERS THROUGH
THURSDAY WHICH WILL BECOME 2 FEET OR LESS FRIDAY INTO THE EARLY
WEEKEND. SEAS INCREASE 2 TO 4 FEET BY LATE SUNDAY INTO MONDAY. WINDS
LESS THAN 15 KNOTS THROUGH SATURDAY NIGHT THEN INCREASING TO 15
KNOTS OR HIGHER LATE SUNDAY INTO MONDAY.
FIRE WEATHER...RELATIVE HUMIDITIES ARE FORECAST TO REMAIN WELL
ABOVE CRITICAL LEVELS WITH NO RED FLAG CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 87 75 87 72 / 10 10 40 20
FORT LAUDERDALE 88 76 87 75 / 10 10 40 20
MIAMI 88 75 87 74 / 10 10 40 20
NAPLES 88 72 84 71 / - 0 30 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...85/AG
AVIATION/RADAR...10/CD
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
757 AM EDT TUE OCT 16 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 622 AM EDT TUE OCT 16 2012
WV IMAGERY AND RUC ANALYSIS SHOWS A WELL-DEFINED SHORTWAVE MOVING
EAST THROUGH SOUTH DAKOTA. STRONG WAA/ISENTROPIC LIFT AHEAD OF THIS
FEATURE AND LOWERING CONDENSATION PRES DEFICITS HAVE ALLOWED FOR AN
AREA OF LIGHT RAIN TO DEVELOP OVER THE NRN HALF OF MN STRETCHING
INTO FAR NRN WI AND WRN UPR MI. INITIAL VERY DRY AIR AT LOW-LVLS AS
NOTED ON 00Z KMPX AND KINL SNDGS HAS KEPT RAIN LIGHT AND REPORTED
CIGS THUS FAR WITH RAIN HAVE BEEN HIGH-BASED...GENERALLY ABV 5KFT.
WAA MID-HIGH CLOUDS SPREADING INTO UPPER MI HAVE BROUGHT TEMPS UP
ABV FREEZING AT MOST LOCATIONS EARLY THIS MORNING AFTER CHILLY UPPER
20S LOWS REACHED EARLIER IN THE EVENING AT MANY CENTRAL AND ERN
LOCATIONS.
AS THE 850-700 MB WARM FRONT NOW REACHING INTO THE WRN CWA MOVES
EAST THROUGH THE AREA TODAY...PCPN WILL SPREAD EAST ACROSS THE CWA.
LIKELY-CATEGORICAL POPS ARE WARRANTED...ESPECIALLY ACROSS THE NRN
TIER AND ERN COUNTIES WHERE THE STRONGEST ISENTROPIC LIFT AND BEST
LLVL MOISTURE TRANSPORT IS LOCATED ALONG/AHEAD OF THE ADVANCING 850
MB WARM FRONT...AS PROGGED BY 00-06Z MODELS. BELIEVE INITIALLY DRY
LOW-LVLS MAY NEGATIVELY IMPACT PCPN AMOUNTS...KEEPING RAINFALL
CLOSER TO STINGIER NAM/WRF-ARW AMOUNTS OF .1-.2 INCH NORTH TO LESS
THAN .1 INCH SOUTH. MODELS HAVE BEEN CONSISTENT WITH THE PCPN ENDING
OVER THE WEST BY EARLY AFTERNOON AND OVER THE EASTERN COUNTIES IN
TUE EVENING AS Q-VECT DIV/SUBSIDENCE SPREADS IN FROM THE WEST IN THE
WAKE OF THE SHORTWAVE AND ASSOC WARM FRONT. LOW CLOUDS/FOG WILL
REMAIN A CONCERN LATE TONIGHT DUE TO CLEARING SKIES FROM WEST AND
LEFTOVER LOW LEVEL MOISTURE FROM AFTN/EVENING RAINFALL SO HAVE
MAINTAINED MENTION OF FOG...ESPECIALLY CENTRAL AND EAST WHERE
UPSLOPE/ONSHORE FLOW OFF LAKE MI COULD ENHANCE FOG CHCS.
WAA WILL DRAW ENOUGH WARM AIR INTO THE REGION TO PUSH MAX READINGS
TODAY INTO UPPER 50S WEST WHILE TEMPS LINGER AROUND 50 OVER THE
EAST. TEMPS SHOULD STAY RELATIVELY MILD TONIGHT (IN THE 40S) AS WE
REMAIN IN WARM SECTOR AHEAD OF DEEPENING SFC LOW NR LAKE WINNIPEG
AND OCCLUDED FRONT STRETCHING INTO THE PLAINS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 622 AM EDT TUE OCT 16 2012
MAJORITY OF FOCUS IN THE LONG TERM IS ON DEEP UPPER TROUGH THAT DIGS
INTO CENTRAL CONUS WEDNESDAY AND THURSDAY. ASSOCIATED SFC TROUGH IS
INITIALLY STRUNG OUT FROM SOUTHERN SASKATCHEWAN AND MANITOBA INTO
MIDDLE MISSISSIPPI RIVER VALLEY ON WEDNESDAY...THEN PHASES INTO A
985-990MB SFC LOW OVER UPPER GREAT LAKES BY THURSDAY MORNING. RAIN
CHANCES ON WEDNESDAY DRIVEN BY BROAD UPPER DIFFLUENCE BTWN THE CNTRL
CONUS UPR LOW AND RIDGE OVER THE NORTHEAST CONUS. MOISTURE ADVECTION
AT H85 ALSO A FACTOR. GOING WITH PREFERRED ECMWF MODELS DEPICTION...
STRONGER UPPER FORCING /MID-LEVEL HEIGHT FALLS AND H85-H7
FRONTOGENESIS/ HOLDS OFF OVR UPR MICHIGAN UNTIL LATER WEDNESDAY AFTN
OVER WESTERN CWA AND ACROSS REST OF CWA ON WEDNESDAY NIGHT. MAX
TEMPS ON WEDNESDAY REMAIN TRICKY PROPOSITION AS IT IS FEASIBLE THERE
COULD BE SOME SUNSHINE THROUGH MIDDAY FOR PORTIONS OF CWA /DEPENDS
ON HOW QUICKLY ANY FOG/LOW CLOUDS GET OUT OF THE WAY IN THE MORNING/
BUT GIVEN ANY SUNSHINE...TEMPS ALOFT ARE PRETTY WARM /H85 TEMPS
PUSHING +10C AND H925 TEMPS OVR +10C/ SO WOULD NOT TAKE MUCH MIXING
TO ALLOW TEMPS TO PUSH PAST 60 DEGREES. KEPT TEMPS OVER FAR WEST
COOLER WITH MORE CLOUDS AND PRECIP EXPECTED BUT TEMPS ELSEWHERE
SHOULD TOP OUT IN THE 60S WHICH WOULD BE THE WARMEST DAY SEEN SINCE
OCTOBER 4TH WHEN TEMPS REACHED UPPER 60S.
NO REAL CHANGE TO PREVIOUS THINKING IN THAT WEDNESDAY NIGHT TURNS
OUT TO BE WET NIGHT OVER CWA. SWATH OF WARM CONVEYOR MOISTURE AND A
BIT OF A TROWAL REGION PIVOT ACROSS CWA AS SFC LOW OCCLUDES WHICH
PUTS AREA IN REGION OF MORE STEADY RAIN MOST OF THE NIGHT. HAVE
LINGERED HIGHER POPS ON THURSDAY OVER KEWEENAW AS THAT AREA REMAINS
ON SOUTHERN EDGE OF H85 THERMAL GRADIENT AND WITHIN H3 JET CORE.
SHORTWAVE ROTATING NORTH IN PERIFERY OF BROAD UPPER LOW MAY BRING
INCREASE TO POPS FOR MUCH OF CWA THURSDAY AFTN/EVENING. PVA FM THE
WAVE AND MORE PERSISTENT LOW-LEVEL MOISTURE ADVECTION IS FORECAST
OVER THE EAST...ALONG WITH SOME ELEVATED INSTABILITY AS SI/S FALL
TOWARD 0C. ANY DETAIL IS REALLY A ROUGH GUESS AS SENSIBLE WEATHER
WILL BE ALTERED WITH JUST A SLIGHT SHIFT IN THE UPR LOW CENTER. DRY
AIR INTRUSION THAT MODELS HAVE HINTED AT FOR A WHILE SHOWS UP LATER
THURSDAY NIGHT INTO FRIDAY. EXPECT STEADIER PRECIP TO DIMINISH BY
THAT TIME...THOUGH CERTAINLY COULD SEE LOW CLOUDS AND MAYBE SOME
LIGHTER PRECIP/DRIZZLE LINGER. CHANCES FOR MORE SIGNIFICANT PRECIP
WOULD BE ENHANCED WHERE THE LOW-LEVEL WINDS ARE MOST ONSHORE AND/OR
PROVIDE MOST UPSLOPE LIFT.
LOW THEN WOBBLES SOUTH/SOUTHEAST LATER FRIDAY AND IS FINALLY KICKED
OFF TOWARD EASTERN CANADA/NEW ENGLAND THROUGH THE UPCOMING WEEKEND.
AFTER SOME WARMER THAN NORMAL TEMPS THROUGH MIDWEEK...TEMPS
GRADUALLY TREND SLIGHTLY BLO NORMAL BY FRIDAY AS COLD AIR ADVECTION
AFFECTS THE UPR LAKES REGION. INTO THE WEEKEND...HAVE SIDED WITH
MORE CONSISTENT ECMWF THAT SHOWS A GENERALLY DRY WEEKEND AS UPR
LAKES IS BTWN EXITING UPR LOW AND ANOTHER TROUGH SLIDING TOWARD
NORTHERN PLAINS BY SUNDAY. SINCE SFC TROUGH DEVELOPS OVER THE PLAINS
BY SUNDAY SW WINDS SHOULD PUSH TEMPS BACK TOWARD NORMAL THROUGH THE
WEEKEND IF NOT SLIGHTLY ABOVE NORMAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 748 AM EDT TUE OCT 16 2012
A WARM FRONT MOVING ACROSS THE AREA WILL SPREAD LIGHT RAIN ACROSS
THE TAF SITES TODAY. FAIRLY DRY AIR AT LOW LEVELS HOWEVER SHOULD KEEP
CONDITIONS VFR AT ALL TAF SITES DESPITE THE RAIN. THERE WILL BE SOME
LLWS AT KCMX AND KSAW THIS MORNING. RAIN WILL LIFT EAST OF THE TAF
SITES IN THE AFTERNOON. POSSIBLE CLEARING TONIGHT WILL BRING THE
POTENTIAL FOR FOG LATE TONIGHT...ESPECIALLY AT KSAW WHERE A
DEVELOPING SSE UPSLOPE FLOW COULD LEAD TO VLIFR CONDITIONS IN
STRATUS/FOG.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 622 AM EDT TUE OCT 16 2012
LOW PRESSURE TROUGH APPROACHING FROM THE NRN PLAINS WILL RESULT
IN SOUTH WINDS OF 15 TO 25 KT WITH AREAS TO NEAR 30 KT OVER ERN LAKE
SUPERIOR THIS AFTERNOON AND EVENING. A DEEPER LOW PRESSURE SYSTEM
MOVING INTO THE UPPER GREAT LAKES ON THURSDAY COULD CAUSE AN
INCREASE IN ERLY WINDS TO 30 KT LATE WED NIGHT AND EARLY
THURSDAY. OTHERWISE...WINDS IN THE VICINITY OF THE LOW SHOULD
GENERALLY REMAIN LESS THAN 20 KTS WEDNESDAY THROUGH SATURDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...VOSS
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
623 AM EDT TUE OCT 16 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 622 AM EDT TUE OCT 16 2012
WV IMAGERY AND RUC ANALYSIS SHOWS A WELL-DEFINED SHORTWAVE MOVING
EAST THROUGH SOUTH DAKOTA. STRONG WAA/ISENTROPIC LIFT AHEAD OF THIS
FEATURE AND LOWERING CONDENSATION PRES DEFICITS HAVE ALLOWED FOR AN
AREA OF LIGHT RAIN TO DEVELOP OVER THE NRN HALF OF MN STRETCHING
INTO FAR NRN WI AND WRN UPR MI. INITIAL VERY DRY AIR AT LOW-LVLS AS
NOTED ON 00Z KMPX AND KINL SNDGS HAS KEPT RAIN LIGHT AND REPORTED
CIGS THUS FAR WITH RAIN HAVE BEEN HIGH-BASED...GENERALLY ABV 5KFT.
WAA MID-HIGH CLOUDS SPREADING INTO UPPER MI HAVE BROUGHT TEMPS UP
ABV FREEZING AT MOST LOCATIONS EARLY THIS MORNING AFTER CHILLY UPPER
20S LOWS REACHED EARLIER IN THE EVENING AT MANY CENTRAL AND ERN
LOCATIONS.
AS THE 850-700 MB WARM FRONT NOW REACHING INTO THE WRN CWA MOVES
EAST THROUGH THE AREA TODAY...PCPN WILL SPREAD EAST ACROSS THE CWA.
LIKELY-CATEGORICAL POPS ARE WARRANTED...ESPECIALLY ACROSS THE NRN
TIER AND ERN COUNTIES WHERE THE STRONGEST ISENTROPIC LIFT AND BEST
LLVL MOISTURE TRANSPORT IS LOCATED ALONG/AHEAD OF THE ADVANCING 850
MB WARM FRONT...AS PROGGED BY 00-06Z MODELS. BELIEVE INITIALLY DRY
LOW-LVLS MAY NEGATIVELY IMPACT PCPN AMOUNTS...KEEPING RAINFALL
CLOSER TO STINGIER NAM/WRF-ARW AMOUNTS OF .1-.2 INCH NORTH TO LESS
THAN .1 INCH SOUTH. MODELS HAVE BEEN CONSISTENT WITH THE PCPN ENDING
OVER THE WEST BY EARLY AFTERNOON AND OVER THE EASTERN COUNTIES IN
TUE EVENING AS Q-VECT DIV/SUBSIDENCE SPREADS IN FROM THE WEST IN THE
WAKE OF THE SHORTWAVE AND ASSOC WARM FRONT. LOW CLOUDS/FOG WILL
REMAIN A CONCERN LATE TONIGHT DUE TO CLEARING SKIES FROM WEST AND
LEFTOVER LOW LEVEL MOISTURE FROM AFTN/EVENING RAINFALL SO HAVE
MAINTAINED MENTION OF FOG...ESPECIALLY CENTRAL AND EAST WHERE
UPSLOPE/ONSHORE FLOW OFF LAKE MI COULD ENHANCE FOG CHCS.
WAA WILL DRAW ENOUGH WARM AIR INTO THE REGION TO PUSH MAX READINGS
TODAY INTO UPPER 50S WEST WHILE TEMPS LINGER AROUND 50 OVER THE
EAST. TEMPS SHOULD STAY RELATIVELY MILD TONIGHT (IN THE 40S) AS WE
REMAIN IN WARM SECTOR AHEAD OF DEEPENING SFC LOW NR LAKE WINNIPEG
AND OCCLUDED FRONT STRETCHING INTO THE PLAINS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 622 AM EDT TUE OCT 16 2012
MAJORITY OF FOCUS IN THE LONG TERM IS ON DEEP UPPER TROUGH THAT DIGS
INTO CENTRAL CONUS WEDNESDAY AND THURSDAY. ASSOCIATED SFC TROUGH IS
INITIALLY STRUNG OUT FROM SOUTHERN SASKATCHEWAN AND MANITOBA INTO
MIDDLE MISSISSIPPI RIVER VALLEY ON WEDNESDAY...THEN PHASES INTO A
985-990MB SFC LOW OVER UPPER GREAT LAKES BY THURSDAY MORNING. RAIN
CHANCES ON WEDNESDAY DRIVEN BY BROAD UPPER DIFFLUENCE BTWN THE CNTRL
CONUS UPR LOW AND RIDGE OVER THE NORTHEAST CONUS. MOISTURE ADVECTION
AT H85 ALSO A FACTOR. GOING WITH PREFERRED ECMWF MODELS DEPICTION...
STRONGER UPPER FORCING /MID-LEVEL HEIGHT FALLS AND H85-H7
FRONTOGENESIS/ HOLDS OFF OVR UPR MICHIGAN UNTIL LATER WEDNESDAY AFTN
OVER WESTERN CWA AND ACROSS REST OF CWA ON WEDNESDAY NIGHT. MAX
TEMPS ON WEDNESDAY REMAIN TRICKY PROPOSITION AS IT IS FEASIBLE THERE
COULD BE SOME SUNSHINE THROUGH MIDDAY FOR PORTIONS OF CWA /DEPENDS
ON HOW QUICKLY ANY FOG/LOW CLOUDS GET OUT OF THE WAY IN THE MORNING/
BUT GIVEN ANY SUNSHINE...TEMPS ALOFT ARE PRETTY WARM /H85 TEMPS
PUSHING +10C AND H925 TEMPS OVR +10C/ SO WOULD NOT TAKE MUCH MIXING
TO ALLOW TEMPS TO PUSH PAST 60 DEGREES. KEPT TEMPS OVER FAR WEST
COOLER WITH MORE CLOUDS AND PRECIP EXPECTED BUT TEMPS ELSEWHERE
SHOULD TOP OUT IN THE 60S WHICH WOULD BE THE WARMEST DAY SEEN SINCE
OCTOBER 4TH WHEN TEMPS REACHED UPPER 60S.
NO REAL CHANGE TO PREVIOUS THINKING IN THAT WEDNESDAY NIGHT TURNS
OUT TO BE WET NIGHT OVER CWA. SWATH OF WARM CONVEYOR MOISTURE AND A
BIT OF A TROWAL REGION PIVOT ACROSS CWA AS SFC LOW OCCLUDES WHICH
PUTS AREA IN REGION OF MORE STEADY RAIN MOST OF THE NIGHT. HAVE
LINGERED HIGHER POPS ON THURSDAY OVER KEWEENAW AS THAT AREA REMAINS
ON SOUTHERN EDGE OF H85 THERMAL GRADIENT AND WITHIN H3 JET CORE.
SHORTWAVE ROTATING NORTH IN PERIFERY OF BROAD UPPER LOW MAY BRING
INCREASE TO POPS FOR MUCH OF CWA THURSDAY AFTN/EVENING. PVA FM THE
WAVE AND MORE PERSISTENT LOW-LEVEL MOISTURE ADVECTION IS FORECAST
OVER THE EAST...ALONG WITH SOME ELEVATED INSTABILITY AS SI/S FALL
TOWARD 0C. ANY DETAIL IS REALLY A ROUGH GUESS AS SENSIBLE WEATHER
WILL BE ALTERED WITH JUST A SLIGHT SHIFT IN THE UPR LOW CENTER. DRY
AIR INTRUSION THAT MODELS HAVE HINTED AT FOR A WHILE SHOWS UP LATER
THURSDAY NIGHT INTO FRIDAY. EXPECT STEADIER PRECIP TO DIMINISH BY
THAT TIME...THOUGH CERTAINLY COULD SEE LOW CLOUDS AND MAYBE SOME
LIGHTER PRECIP/DRIZZLE LINGER. CHANCES FOR MORE SIGNIFICANT PRECIP
WOULD BE ENHANCED WHERE THE LOW-LEVEL WINDS ARE MOST ONSHORE AND/OR
PROVIDE MOST UPSLOPE LIFT.
LOW THEN WOBBLES SOUTH/SOUTHEAST LATER FRIDAY AND IS FINALLY KICKED
OFF TOWARD EASTERN CANADA/NEW ENGLAND THROUGH THE UPCOMING WEEKEND.
AFTER SOME WARMER THAN NORMAL TEMPS THROUGH MIDWEEK...TEMPS
GRADUALLY TREND SLIGHTLY BLO NORMAL BY FRIDAY AS COLD AIR ADVECTION
AFFECTS THE UPR LAKES REGION. INTO THE WEEKEND...HAVE SIDED WITH
MORE CONSISTENT ECMWF THAT SHOWS A GENERALLY DRY WEEKEND AS UPR
LAKES IS BTWN EXITING UPR LOW AND ANOTHER TROUGH SLIDING TOWARD
NORTHERN PLAINS BY SUNDAY. SINCE SFC TROUGH DEVELOPS OVER THE PLAINS
BY SUNDAY SW WINDS SHOULD PUSH TEMPS BACK TOWARD NORMAL THROUGH THE
WEEKEND IF NOT SLIGHTLY ABOVE NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 130 AM EDT TUE OCT 16 2012
A TROUGH WILL MOVE TOWARD THE AREA LATE TONIGHT BRINGING THICKENING
CLOUDS AND THE POTENTIAL FOR SOME LIGHT RAIN LATE TONIGHT. EXPECT
RAIN WITH MVFR CIGS TO MOVE IN TUESDAY AT KCMX AND CONDITIONS TO
STAY VFR THROUGH THE PERIOD AT KSAW AND KIWD. THERE WILL BE SOME
LLWS AT TIMES AT ALL SITES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 622 AM EDT TUE OCT 16 2012
LOW PRESSURE TROUGH APPROACHING FROM THE NRN PLAINS WILL RESULT
IN SOUTH WINDS OF 15 TO 25 KT WITH AREAS TO NEAR 30 KT OVER ERN LAKE
SUPERIOR THIS AFTERNOON AND EVENING. A DEEPER LOW PRESSURE SYSTEM
MOVING INTO THE UPPER GREAT LAKES ON THURSDAY COULD CAUSE AN
INCREASE IN ERLY WINDS TO 30 KT LATE WED NIGHT AND EARLY
THURSDAY. OTHERWISE...WINDS IN THE VICINITY OF THE LOW SHOULD
GENERALLY REMAIN LESS THAN 20 KTS WEDNESDAY THROUGH SATURDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...VOSS
MARINE...VOSS
AREA FORECAST DISCUSSION...UPDATED FOR 12Z TAFS
NWS TWIN CITIES/CHANHASSEN MN
535 AM CDT TUE OCT 16 2012
.DISCUSSION...ISSUED 417 AM CDT
TODAY WILL BE THE LAST DAY OF ABOVE NORMAL TEMPS FOR A WHILE AS A
POWERFUL STORM SYSTEM ARRIVES ON WEDNESDAY. TEMPS WILL COOL DOWN
THURSDAY AND FRIDAY...BUT A BRIEF WARM UP IS EXPECTED FOR THE
WEEKEND AHEAD OF THE NEXT SYSTEM FORECAST TO AFFECT THE REGION
EARLY NEXT WEEK.
TODAY...MORNING IR IMAGERY WITH 500MB HEIGHTS SHOWED SOME MID
LEVEL CLOUDS AHEAD OF A SHORTWAVE ABOUT TO CROSS THE MN/DAKOTA
BORDER. ISENTROPIC LIFT AHEAD OF THIS WAVE WAS ENOUGH TO PRODUCE A
FEW SPRINKLES ACROSS CENTRAL MINNESOTA AND NORTHERN
WISCONSIN...BUT DRY AIR IN THE LOWEST 6000FT OF THE ATMOSPHERE WAS
KEEPING THE MEASURABLE RAINFALL AT BAY. AT THE SURFACE WARM AIR
ADVECTION TOGETHER WITH THE AFOREMENTIONED CLOUD DECK KEPT
OVERNIGHT LOW TEMPERATURES IN THE MID 50S ACROSS THE REGION. LATER
TODAY THE LIGHT PRECIP WILL MOVE EASTWARD...AND WINDS WILL
GRADUALLY BECOME WEST NORTHWEST AS A PRESSURE TROUGH PASSES
THROUGH. DIURNAL MIXING SHOULD BE ABLE TO TAP INTO THE H850 TEMPS
RANGING FROM 10 TO 12C...SO EXPECT HIGH TEMPS TO APPROACH 70 ACROSS
MOST OF MINNESOTA...WITH MID 60S IN WESTERN WISCONSIN WHERE CLOUDS
WILL HINDER THE DAYTIME HEATING.
WEDNESDAY THROUGH THURSDAY...AN UPPER LEVEL JET WILL CROSS THE HIGH
PLAINS AND CARVE OUT A LONG WAVE TROUGH OVER THE MIDWEST ON
WEDNESDAY. STRONG UPPER LEVEL FORCING IN THE LEFT EXIT REGION WILL
LEAD TO A BROAD AREA OF LOW PRESSURE NEAR THE MN/CANADA BORDER BY
WEDNESDAY AFTERNOON. TO THE SOUTH A COLD FRONT WILL SWEEP THROUGH
THE REGION AND FRONTOGENETICAL FORCING TOGETHER WITH THE LARGE SCALE
QG ASCENT WILL YIELD A FEW SHOWERS MOVING FROM WEST TO EAST
WEDNESDAY MORNING. THIS CYCLONE WILL QUICKLY MATURE...WITH MODELS
INDICATING A DRY SLOT ACROSS SOUTHERN MINNESOTA BY WEDNESDAY
AFTERNOON. THE DRY POST FRONTAL AIRMASS WILL EASILY MIX OUT WITH RH
VALUES FALLING INTO THE 20S ACROSS THE MINNESOTA RIVER VALLEY AMIDST
WESTERLY WINDS OF 20 TO 30 MPH. DEPENDING ON THE AMOUNT OF PRECIP
THAT FALLS EARLIER IN THE DAY...FIRE WEATHER PRODUCTS MAY BE
WARRANTED DURING THAT AFTERNOON. AS THE UPPER LEVEL JET STREAK
ROUNDS THE BAST OF THE TROUGH...THE CYCLONE WILL OCCLUDE AND BECOME
VERTICALLY STACKED BY THURSDAY. SHORTWAVES OF ENHANCED VORTICITY
WILL ROTATE AROUND THIS CUT OFF LOW AND BE THE FOCUS FOR ADDITION
ROUNDS OF PRECIPITATION. GFS 16.00 IS SLIGHTLY QUICKER THAN THE NAM
OR ECMWF...BUT ALL DEVELOP A TROWEL FEATURE WITH A MAX OF
PRECIPITATION ACROSS THE RED RIVER/MINNESOTA RIVER VALLEYS ON
THURSDAY. THEREFORE INCREASED THE POPS IN THOSE AREAS.
FRIDAY THROUGH MONDAY...BY FRIDAY THE UPPER LEVEL WAVE BEGINS TO MAKE
ITS WAY TOWARDS THE NEW ENGLAND AREA...BUT STILL EXPECT TO HAVE
OVERCAST SKIES AND COOL TEMPS WITH BRISK NORTHWEST WINDS CONTINUING
ACROSS THE REGION...AND A FEW LIGHT SHOWERS LINGERING IN EASTERN
MINNESOTA AND WISCONSIN. SWITCHING GEARS BACK TO THE LARGE
SCALE...IN THE GULF OF ALASKA...THE GEM/GFS/ECMWF 16.00 H250
FORECAST VALID FOR FRIDAY SHOWS A REMARKABLY SIMILAR JET SETTING
UP...WHICH WILL AFFECT THE REGION EARLY NEXT WEEK. TEMPORARY
RIDGING ACROSS THE CENTRAL CONUS SHOULD ALLOW SATURDAY AND SUNDAY
TO BE DRY AHEAD OF THE AFOREMENTIONED APPROACHING SYSTEM. SUNDAYS
H850 TEMPS OF 12-14C ACROSS THE REGION SHOULD GIVE WAY TO HIGH
TEMPS IN AT LEAST THE LOW TO MID 60S...SO HAVE BUMPED THESE UP
FROM THE PREVIOUS FORECAST. THERE IS SOME DISAGREEMENT BETWEEN THE
LONG RANGE MODELS IN HOW THEY HANDLE THE JET EVOLUTION...WITH THE
GFS MORE ZONAL...THE GEM MORE AMPLIFIED AND THE ECMWF IN BETWEEN
THE TWO. THEREFORE DID NOT STRAY FROM THE MODEL CONSENSUS.
&&
.AVIATION.../12Z TAF ISSUANCE/
WEAK SURFACE TROUGH IN W MN HASN`T MADE A LOT OF EWRD PROGRESS
OVERNITE AND MODELS STILL WASH IT OUT AS STRONGER TROF DEVELOPS
FARTHER WEST AHD OF UPPER TROF MOVING ACRS THE PACIFIC NW. SFC TROF
MAY MAKE IT ABT AS FAR EAST AS STC. STILL WDSRPD MID CLDS WITH BASES
GNRLY AOA 8K ACROSS AREA. MAY SEE A BRF SPRINKLE NEXT FEW HOURS AT
STC/AXN. HRRR AND GFS HAVE BEEN TRYING TO GENERATE ANOTHER AREA OF
-SHRA ACRS SC MN...AND RADAR IN LAST FEW SCANS HAS BEEN SHOWING PCPN
TRYING TO DVLP ARND MKT TO FRM. WILL PUT VCSH AT EAU 14Z-18Z. ATTM
WILL KEEP S OF MSP...BUT MAY ADJUST BEFORE ISSUE TIME IF AREA
EXPANDS NORTH.
KMSP...VFR THRU ABT NEXT 24 HRS WITH LOWERING CONDS AHEAD OF STRONG
UPPER TROF MOVING ACRS WED MRNG. IN THE SHORT TERM RADAR IS SHOWING
-SHRA DVLPG S OF MSP IN THE MKT/FRM AREA. WILL MONITOR MAY PUT IN
AT LEAST VCSH IF AREA DEVELOPS NORTH.
/OUTLOOK FOR KMSP/
WEDNESDAY...MVFR CEILINGS POSSIBLE WITH SHRA. SOUTHWEST WINDS 5 TO
15 KT SHIFTING WEST 15 TO 25 KT.
WEDNESDAY NIGHT...MVFR CEILINGS POSSIBLE LATE ALONG WITH CHANCE OF
SHRA. WEST WINDS 10 TO 20 KT.
THURSDAY AND THURSDAY NIGHT...MVFR CEILINGS EXPECTED WITH MVFR
VISIBILITY DURING SHRA. IFR CONDITIONS POSSIBLE. WEST WINDS 15 TO
25 KT WITH GUSTS ABV 30KT SHIFTING NORTHWEST.
&&
.FIRE WEATHER...
ON WEDNESDAY AFTERNOON STRONG POST FRONTAL WINDS OF 20 TO 30 MPH
LOOK TO REMAIN ON TRACK ACROSS WESTERN MINNESOTA. MEANWHILE...RH
VALUES COULD DROP INTO THE 20S ACROSS THE REGION...SPECIFICALLY
THE MINNESOTA RIVER VALLEY. DEPENDING ON AMOUNT OF PRECIPITATION
THAT FALLS DURING THE MORNING...AND THE AMOUNT OF CLEARING/DRYING
THAT TAKES PLACE DURING THE AFTERNOON...A RED FLAG WARNING MAY BE
NEEDED.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
JRB/BAP
AREA FORECAST DISCUSSION
NWS SPOKANE WA
436 AM PDT Tue Oct 16 2012
.SYNOPSIS...Windy conditions with scattered rain and high mountain
snow showers will affect the region today. Wind gusts of 35 to 50 mph
will be likely through this evening over portions of the Inland
Northwest. A drier, more stable pattern is expected for Wednesday
and Thursday, before more precipitation chances enter late in the
week with cooler temperatures.
&&
.DISCUSSION...
...VERY WINDY CONDITIONS TODAY...
Today and tonight...The cold front continues to move southeast
across the forecast area this morning with the back edge just south
of the I-90 corridor as of 08Z. The main area of steady rain is
confined to Shoshone county but widely scattered showers are
popping up all across the area in the unstable post frontal air
mass. A few lightning strikes have been recorded across the extreme
northern Cascades and across southern BC. The cold pool aloft will
keep things unsettled enough for a slight chance of thunderstorms
through about 15Z before the best forcing moves east. Gusty winds
are starting to increase as the surface pressure gradient
strengthens between the deepening low over southern Alberta and high
pressure off the coast. The gradient is expected to max out late
this morning to early afternoon. The benchmark that will support a
high wind warning is at least a 24mb difference between Lethbridge,
Alberta (CYQL) and Yakima (KYKM) along with synoptic support from a
jet streak overhead. We will be just shy of the gradient and the jet
will sag to the south this afternoon. This likely means that we will
be seeing a high end wind advisory. There could possibly be one or
two of the windier sites breaking into high wind criteria but
widespread damaging winds are not expected with this system. It will
also be a fast mover, with the low sliding into the Canadian
Prairies by 00z, weakening the gradient. No changes made to the
ongoing wind advisory at this time.
Another concern will be snow levels for the east slopes of the
Cascades. Models are bringing the 850mb 0C line along the crest with
the NAM12 down to -1C this morning. Radar mosaic is showing some
evidence of a convergent zone. The HRRR model agrees, but shows the
plume drifting south along the crest into slightly warmer air.
Depending on the location and persistence of this feature, some of
the higher valleys could see some light snowfall accumulation. After
a relatively mild morning, due to strong mixing by gusty winds,
temperatures will not warm very much today as cold air advection
takes over. Expect chilly temperatures tonight with most of the
northern valleys dipping below the freezing mark. For other valley
locations, mid 30s will be common. /Kelch
Wednesday through Thursday...Latest models are in good agreement
for this period. A quite break will grace the region as a weak
but perceptible short wave ridge builds over the forecast area in
the wake of Tuesday`s unpleasantness. Residual breezy winds and
lingering showers over the Idaho Panhandle will decrease Wednesday
morning as surface high pressure settles over the region. Wednesday`s
highs will peak right around seasonal normal with generally partly
cloudy to mostly sunny skies. The quiet break will continue on
Thursday although the ridge axis will pass to the east of the
region and open the way for increasing high clouds as the next
weather system approaches. The retreat of the ridge axis will
allow some warm advection to begin on Thursday in the pre-frontal
southwest flow regime...promoting high temperatures once again
slightly above normal...but with sunshine filtered through
thickening clouds especially across the northern zones.
Thursday night and Friday...The GFS and ECMWF models advertise a
ridge breakdown and subsequent cold front passage either Thursday
night (GFS) or Friday (EC). Both models have stuck to their
respective timing differences over the last few runs. The driving
force of a 120-140kt jet over the Gulf Of Alaska associated with
this wave suggest the faster GFS may be the best solution to work
with. Forecast will be based upon this reasoning...which yields
high pops over much of the forecast area Thursday night and into
Friday morning as a strong fetch of precipitable water enhances
along the cold front with good and well defined jet divergence and
differential PVA. High temperatures Friday are low
confidence...with the current forecast reflecting an assumption
of a morning precipitation threat followed by good afternoon
adiabatic mixing promoting high temperatures above average...but
if the EC is correct then highs may top out closer to average. In
any event...after the relatively benign conditions of Wednesday
and Thursday...there is high confidence that Friday will bring a
change to this pattern.
Friday night through Monday...Things get rather messy and
uncertain during this period with respect to timing multiple minor
waves and fronts in a much more progressive...cooler and wet
pattern. Where certainty is higher is the overall pattern
reflected by all the latest models featuring a cool zonal or
moderately cold troffy flow regime with the storm track to the
south of the forecast area. This argues for a broad brush approach
featuring a chance of valley rain and mountain snow each day
through the weekend and early next week...with the added
possibility of some overnight non-accumulating snow flakes down
to the valley and basin floors if any particular disturbance rides
through during the overnight or early morning hours. The deep
basin in the lee of the Cascades will probably miss out on any
significant precipitation given the rain shadow promoting mean
westerly flow. During this period the mountains above 4000 to 5000 feet
are likely to receive their first significant snow
accumulations...slowly building up to three to seven inches
through the weekend. Thus...confidence is high for a raw...breezy
and occasionally wet regime during this period...although
confidence is low regarding timing of any of the expected
transient focusing mechanisms and fronts. /Fugazzi
&&
.AVIATION...
12Z TAFS: The upper level trough has moved over the region this
morning with scattered thunderstorms across the panhandle of
Idaho. Convection has moved east of most terminals, except KLWS.
A line of storms will affect extreme southeast WA and the central
panhandle through about 15z. Moist upslope flow into KGEG, KSFF, KCOE
and at KPUW will result in some low stratus before drier air aloft
begins to clear skies out and improve conditions. Winds are beginning
to gust out of the west and southwest and will intensify by 18Z
with gusts to of 35 to 40 kts common. Scattered showers will
affect the Idaho panhandle through this afternoon, then diminish.
Winds will start to slacken by 01Z then become light after 06Z. As
winds become light, low stratus may form at any and all terminals.
/EK
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 56 37 54 37 60 43 / 30 10 0 0 10 60
Coeur d`Alene 55 34 53 33 60 40 / 50 10 0 0 10 60
Pullman 57 31 53 36 62 42 / 70 10 0 0 10 60
Lewiston 63 39 58 40 68 47 / 70 10 0 0 10 50
Colville 60 29 57 34 60 36 / 30 10 10 0 10 60
Sandpoint 53 33 52 32 57 39 / 70 10 10 0 10 60
Kellogg 50 35 48 32 56 39 / 90 20 10 0 10 70
Moses Lake 62 34 60 37 64 42 / 10 0 0 0 10 20
Wenatchee 58 40 57 39 65 45 / 10 0 0 0 10 30
Omak 61 33 59 37 62 38 / 10 0 0 10 10 60
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Wind Advisory until 8 PM PDT this evening for Coeur d`Alene Area-
Idaho Palouse-Lewiston Area.
WA...Wind Advisory until 8 PM PDT this evening for Lower Garfield and
Asotin Counties-Moses Lake Area-Spokane Area-Upper Columbia
Basin-Washington Palouse-Waterville Plateau-Wenatchee Area.
&&
$$
AREA FORECAST DISCUSSION
NWS MIAMI FL
121 PM EDT TUE OCT 16 2012
.AVIATION...
ALTHOUGH VFR CONDITIONS WILL PREVAIL THROUGH THE BULK OF THE
PERIOD...A FEW SHOWERS DEVELOPING THIS AFTERNOON COULD RESULT IN
A BRIEF PERIOD OR TWO WITH SUB VFR CIGS/VSBYS. THE LATEST HIRES
MODEL GUIDANCE REFLECTS THIS AND GENERALLY INDICATES THE BEST
COVERAGE SETTING UP ACROSS THE SOUTHERN HALF OF THE FL PENINSULA
THROUGH THE LATE AFTERNOON AND EARLY EVENING PERIODS.
THEREFORE...WILL CONTINUE TO INCLUDE VCSH FOR THESE TAF SITES
THROUGH THIS PERIOD TODAY. WINDS WILL REMAIN LIGHT THROUGH THE
PERIOD. FOR WEDNESDAY...RAIN CHANCES WILL SLIGHTLY INCREASE AS AN
UPPER TROUGH ADVANCES EWD ACROSS THE STATE. WILL INTRODUCE VCSH
THROUGH THE LATTER HALF OF THIS PACKAGE AS A RESULT.
&&
.PREV DISCUSSION... /ISSUED 939 AM EDT TUE OCT 16 2012/
UPDATE...
THE MORNING SURFACE ANALYSIS SHOWED A COLD FRONT EXTENDING
SOUTHWEST ACROSS THE FLORIDA PENINSULA FROM AROUND DAYTONA BEACH
TO JUST NORTH OF TAMPA. PLENTY OF DRY AIR WITH DEWPOINTS IN THE
LOWER 50S HAS ALREADY BEGUN TO SPREAD SOUTH INTO NORTHERN FLORIDA
IN ITS WAKE EARLY THIS MORNING. FARTHER SOUTH AHEAD OF THIS
BOUNDARY...A DECENT AMOUNT OF LOW-LEVEL MOISTURE WITH DEWPOINTS
REMAINING IN THE LOWER 70S WILL BE ANTICIPATED TODAY. THE MORNING
UPPER AIR SOUNDING IN MIAMI REFLECTED THIS MOISTURE UP TO AROUND
10 KFT OR 700 MB...THEN VERY DRY ABOVE THIS POINT. LOW-LEVEL WIND
PROFILE SHOWED NNE FLOW. AS A RESULT...THE LATEST HRRR AND WRF
MODEL REFLECTIVITIES INDICATE THE BEST CHANCE FOR MAINLY ISOLATED
SHOWERS LATER THIS AFTERNOON AND EVENING ACROSS THE SOUTHERN
EXTENT OF THE FL PENINSULA TODAY. FOR THE MORNING UPDATE...WE WILL
SLIGHTLY INCREASE THE AFTERNOON RAINFALL CHANCES OVER THESE SRN
AREAS AND CONTINUE THEM INTO THE EARLY EVENING HOURS.
OTHERWISE...THE PREVIOUS FORECAST PACKAGE REMAINS ON TRACK. 85/AG
PREV DISCUSSION... /ISSUED 727 AM EDT TUE OCT 16 2012/
AVIATION...
VFR CONDITIONS EXPECTED THROUGH THE PERIOD. A FEW SHRA POSSIBLE THIS
AFTERNOON MAINLY OVER THE INTERIOR WITH STEERING FLOW TO THE SOUTH.
LATEST HIGH RESOLUTION SHORT TERM GUIDANCE SUGGESTS THE DEVELOPMENT
WILL BE LATE AND MOSTLY FROM BROWARD COUNTY AND TO THE SOUTH SO
PLACED VCSH IN FOR THOSE TERMINALS AND REMOVED FROM THE KAPF TAF.
OFFSHORE LIGHT WIND FLOW ALONG BOTH COASTS THIS MORNING WILL BECOME
ONSHORE ALONG THE E CST AFT 15-16Z AND AFT 17-18Z AT KAPF AND THEN
OFFSHORE ONCE AGAIN THIS EVENING. /KOB
PREV DISCUSSION... /ISSUED 351 AM EDT TUE OCT 16 2012/
SHORT TERM (TODAY-THURSDAY)...
E COAST UPPER TROUGH LIFTS TO THE NE PULLING HURRICANE RAFAEL NORTH
-WARD WHILE THE ASSOCIATED COLD FRONT CURRENTLY OVER N FLA...SLOWLY
MOVES SOUTHWARD AS THE UPPER FLOW BECOMES ZONAL. BUT OVERNIGHT AND
INTO EARLY WEDNESDAY MORNING ANOTHER SHORT WAVE DIVES INTO THE SE
U.S. AND LIFTS NE BUT THE FRONT LIMPS INTO S FLA BY WED MORNING
POSSIBLY STALLING AND WASHING OUT. HIGH PRESSURE THEN BUILDS OVER
THE EASTERN U.S. THURSDAY. PLENTY OF DRY AIR MOVING OVER S FLA BUT
ENOUGH MOISTURE IN PLACE TO TRIGGER SHOWER ACTIVITY THIS AFTERNOON
ACROSS MAINLY THE EASTERN HALF OF THE S FLA PENINSULA. ON WEDNESDAY
WITH THE STALLING/DISSIPATING BOUNDARY AND POSSIBLE INFLUENCE OF
THE SHORT WAVE CROSSING ACROSS N FLA...THERE MAY BE A CHANCE OF
SHOWERS AND SOME THUNDERSTORMS ACROSS THE AREA WITH THE BETTER
CHANCE OF PRECIPITATION INTERIOR AND E DUE TO WESTERLY STEERING
FLOW. ON THURSDAY...SOME DRIER AIR MOVES OVER S FLA AGAIN AND
WITH A MINOR DECREASE IN POPS.
MIAMI BEACH HAD SOME COASTAL FLOODING ON MONDAY WITH SOME MINOR
INUNDATION OF SOME ROADWAYS DURING HIGH TIDE. WITH WATER LEVELS
STILL RUNNING A BIT ABOVE NORMAL...DURING THE HIGH TIDE CYCLE TODAY
WHICH IS BETWEEN 9 AND 10 AM...SOME MINOR FLOODING MAY OCCUR
AGAIN. WITH DECREASING WINDS AND WITH TIDES RETURNING TO NORMAL
THIS POTENTIAL FLOODING AT MIAMI BEACH WILL DIMINISH THROUGH THE
WEEK. LITTLE IN THE WAY OF ADDITION RAINFALL IS EXPECTED TODAY BUT A
POTENTIAL OF HEAVIER RAINFALL ON WEDNESDAY THAT COULD BECOME
CONCENTRATED AND THE ADDITIONAL RAINFALL COULD RESULT IN ADDITIONAL
FLOODING OR STANDING WATER CONCERNS. SOMETHING TO WATCH.
LONG TERM (FRIDAY-MONDAY)...
A STRONG CLOSED MID/UPPER LOW DIVES INTO THE GREAT LAKES REGION
FRIDAY AND SATURDAY THEN LIFTS NE INTO E CANADA AS A HIGH PRESSURE
RIDGE MOVES EASTWARD AND OVER THE E U.S. BY EARLY NEXT WEEK. THE
ASSOCIATED COLD FRONT...BASED ON GFS/ECMWF COMPARISON...APPEARS TO
NOT NEAR S FLA. SO...MOISTURE REMAINS IN PLACE THROUGH THE PERIOD
WITH WARM, HUMID CONDITIONS PREVAILING THROUGH THE FORECAST PERIOD
ALONG WITH A DAILY CHANCE OF SHOWERS/TSTORMS. WITH WESTERLY STEERING
WINDS THE INTERIOR AND E WILL BE FAVORED.
MARINE...ATLC SEAS OF 2 TO 4 FEET...ESPECIALLY OFF OF PALM BEACH
COUNTY...THROUGH TONIGHT THEN 2 TO 3 FEET ALL ATLC WATERS THROUGH
THURSDAY WHICH WILL BECOME 2 FEET OR LESS FRIDAY INTO THE EARLY
WEEKEND. SEAS INCREASE 2 TO 4 FEET BY LATE SUNDAY INTO MONDAY. WINDS
LESS THAN 15 KNOTS THROUGH SATURDAY NIGHT THEN INCREASING TO 15
KNOTS OR HIGHER LATE SUNDAY INTO MONDAY.
FIRE WEATHER...RELATIVE HUMIDITIES ARE FORECAST TO REMAIN WELL
ABOVE CRITICAL LEVELS WITH NO RED FLAG CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 75 87 72 87 / 10 40 20 30
FORT LAUDERDALE 76 87 75 87 / 10 40 20 30
MIAMI 75 87 74 87 / 10 40 20 30
NAPLES 72 84 71 86 / 0 30 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...55/CWC
AVIATION/RADAR...85/AG
AREA FORECAST DISCUSSION
NWS CARIBOU ME
509 PM EDT TUE OCT 16 2012
.SYNOPSIS...
HIGH PRESSURE WILL BUILD OVER THE AREA TONIGHT AND REMAIN ACROSS
THE REGION WEDNESDAY INTO WEDNESDAY NIGHT. THE HIGH WILL MOVE EAST
OF THE STATE ON THURSDAY.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
UPDATE: QUICK UPDATE TO ADJUST THE TEMPERATURES/DEWPOINTS DOWN AS
COLDER AIR MOVING SE FROM CANADA. ADJUSTED THE POPS AS WELL TO
ACCOUNT FOR THE RADAR WHICH SHOWED THE BULK OF RAIN NOW INTO NEW
BRUNSWICK AND ANOTHER SMALLER AREA MOVING ACROSS NE AROOSTOOK
COUNTY. THE LATEST RUC HAD THIS HANDLED NICELY.
PREVIOUS DISCUSSION...
THE LOW WHICH BROUGHT RAIN TO THE AREA MUCH OF THE DAY WILL
QUICKLY LIFT NORTHEAST AND AWAY TONIGHT AS HIGH PRESSURE BUILDS
OVER THE STATE. THIS WILL ALLOW CLEARING THROUGHOUT THE REGION
TONIGHT AND TEMPS WILL DROP TO NEAR OR JUST BELOW FREEZING IN MOST
AREAS. HIGH PRESSURE WILL REMAIN OVER THE REGION WEDNESDAY
BRINGING SUNSHINE WITH AFTERNOON TEMPS RANGING FROM THE UPPER 50S
DOWNEAST TO THE LOW 50S OVER THE NORTH. WINDS WILL BE VERY LIGHT
AS THE HIGH CRESTS OVER THE REGION.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
NORTHERN NEW ENGLAND WILL BEGIN THIS FORECAST PERIOD UNDERNEATH AN
UPPER RIDGE. THIS WILL ALLOW FOR ABOVE NORMAL TEMPERATURES AND
DRY WEATHER. HIGH CLOUDS WILL SPILL OVER THE RIDGE AXIS FOR MOSTLY
CLOUDY SKIES. WILL HAVE TO WATCH OUT FOR LOW CLOUDS AND FOG ALONG
THE COASTAL ZONES LATE THURSDAY NIGHT AND EARLY FRIDAY MORNING DUE
TO A STRONG ONSHORE FLOW.
WINDS WILL INCREASE ON FRIDAY AS AN OCCLUDED FRONT APPROACHES FROM
THE WEST. EXPECT RAIN OR RAIN SHOWERS TO DEVELOP DURING THE DAY
ACROSS NORTHERN AND DOWNEAST MAINE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AN OCCLUDED FRONT WILL CROSS THE REGION FRIDAY NIGHT THROUGH
SATURDAY NIGHT...THOUGH UNCERTAINTY STILL EXISTS REGARDING HOW
QUICKLY THE FRONT MOVES EAST OF THE REGION LATER SATURDAY THROUGH
SATURDAY NIGHT. AN AREA OF RAIN WILL CROSS THE REGION IN ADVANCE
OF THE OCCLUSION FRIDAY NIGHT INTO SATURDAY...THEN TAPER TO
SHOWERS IN THE WAKE OF THE FRONT LATER SATURDAY INTO SATURDAY
NIGHT DEPENDENT ON THE TIMING OF THE FRONT. SHOWERS WRAPPING
AROUND THE EXITING SYSTEM COULD BRING A CHANCE OF SHOWERS TO THE
NORTH/MOUNTAINS SUNDAY...WITH PARTLY CLOUDY SKIES DOWNEAST. HIGH
PRESSURE SHOULD THEN BUILD ACROSS THE REGION MONDAY. A COLD FRONT
COULD THEN BRING A CHANCE OF SHOWERS TUESDAY. TEMPERATURES SHOULD
BE AT SLIGHTLY ABOVE NORMAL LEVELS SATURDAY THROUGH MONDAY...WITH
NEAR NORMAL LEVEL TEMPERATURES TUESDAY.
&&
.AVIATION /21Z TUESDAY THROUGH SUNDAY/...
NEAR TERM: CONDITIONS WILL IMPROVE TO VFR TONIGHT THEN REMAIN VFR
IN MOSTLY CLEAR SKIES ON WEDNESDAY.
SHORT TERM: MVFR CIGS AND VSBYS ARE POSSIBLE AT KBHB AND KBGR LATE
THURSDAY NIGHT AND EARLY FRIDAY MORNING DUE TO LOW CLOUDS AND FOG.
MVFR CIGS AND VSBYS ARE POSSIBLE FRIDAY AFTERNOON AT ALL TAF SITES
DUE TO LOW CLOUDS AND SHOWERS AS AN OCCLUDED FRONT MOVES INTO THE
REGION. MVFR/IFR CONDITIONS ARE EXPECTED ACROSS THE REGION FRIDAY
NIGHT INTO EARLY SATURDAY NIGHT...WITH MVFR CONDITIONS LATER
SATURDAY NIGHT. OCCASIONAL MVFR CONDITIONS COULD LINGER ACROSS
THE NORTH/MOUNTAINS SUNDAY...WITH VFR CONDITIONS DOWNEAST.
&&
.MARINE...
NEAR TERM: AN SCA WILL CONTINUE TONIGHT FOR NORTHWEST WINDS
GUSTING UP TO 25 KT. WINDS WILL DIMINISH LATE TONIGHT AND THEN BE
LIGHT ON WEDNESDAY AS THE HIGH CRESTS OVER THE WATERS.
SHORT TERM: SCA CONDITIONS ARE LIKELY THURSDAY WITH WAVE HEIGHTS IN
THE 4 TO 7 FOOT RANGE AND FRIDAY WITH WAVE HEIGHTS IN THE 6 TO 9
FOOT RANGE AND WIND GUSTS IN EXCESS OF 25 KNOTS.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 AM EDT WEDNESDAY FOR ANZ050>052.
&&
$$
NEAR TERM...BLOOMER/HEWITT
SHORT TERM...OKULSKI
LONG TERM...NORCROSS
AVIATION...BLOOMER/HEWITT
MARINE...BLOOMER/HEWITT/OKULSKI
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
657 PM EDT TUE OCT 16 2012
.SYNOPSIS...
ISSUED AT 345 PM EDT TUE OCT 16 2012
A WARM FRONT WILL LIFT NORTH THROUGH MICHIGAN TONIGHT AND MAY TOUCH
OFF A FEW SHOWERS AND THUNDERSTORMS. IN THE WAKE OF THIS WARM
FRONT... WEDNESDAY WILL BE THE WARMEST DAY OF THE WEEK AS
TEMPERATURES RISE TO NEAR 70. THE WARM UP WILL BE SHORT LIVED
HOWEVER BECAUSE ANOTHER COLD FRONT WILL SWEEP THROUGH THE REGION ON
WEDNESDAY NIGHT AND BRING A WIDESPREAD AREA OF RAIN WITH IT.
COOLER AND SHOWERY WEATHER CAN BE EXPECTED FOR THURSDAY AND FRIDAY
AS A LOW PRESSURE SYSTEM OVER ALBERTA CANADA MOVES SOUTHEAST AND
STALLS OVER THE GREAT LAKES REGION. THAT SYSTEM SHOULD PUSH OUT OF
THE REGION EARLY SATURDAY LEADING TO A PREDOMINATELY DRY PATTERN FOR
THE COMING WEEKEND WITH MODERATING TEMPERATURES.
&&
.UPDATE...
ISSUED AT 657 PM EDT TUE OCT 16 2012
I UPDATED THE GRIDS TO HAVE LIKELY POP ALONG THE ROUTE 10
CORRIDOR THIS EVENING INTO EARLY TONIGHT . THIS IS TO REFLECT THE
CURRENT AREA OF SHOWERS STRENGTHENING THIS EVENING AS IT MOVES
ACROSS THE AREA ( MOSTLY NORTH OF I-96).
AN AREA OF SHOWERS CONTINUES TO DEVELOP AND MOVE EAST NORTHEAST
ACROSS CENTRAL LAKE MICHIGAN (MOSTLY N OF MKE TO MKG LINE) EARLY
THIS EVENING. THIS IS ON THE NOSE A STRENGTHENING LOW LEVEL JET
(40-45 KNOT CORE EAST OF THE QUAD CITIES AT 21Z). THIS AREA WILL
LIKELY INTENSIFY THIS EVENING AS THE LOW LEVEL JET STRENGTHENS
AFTER DARK. WITH THE CORE OF THE JET CROSSING THE GRR AREA AROUND
MIDNIGHT...I WOULD EXPECT MOST OF THE ACTIVITY TO BE NORTH OF
INTERSTATE 96. WITH A DRY SUB CLOUD LAYER SEEN ON THE RAP AND LAPS
SOUNDINGS THIS EVENING... I WOULD EXPECT GUSTY WINDS OUT OF ANY
SHOWER THAT MOVES ACROSS THE AREA UNTIL THE BOUNDARY LAYER EITHER
MOISTENS OR A STRONGER RADIATION INVERSION DEVELOPS. MOST OF THIS
ACTIVITY WILL BE EAST OF THE CWA AFTER 02Z (SHORTWAVE IS EAST OF
THE AREA).
THE INSTABILITY IS MOSTLY AT MID LEVELS AND THE STRONGEST LIFT
NORTH OF MKG IS NEAR THE -20C ISOTHERM AND THAT AREA IS FORECAST
TO BE SATURATED THIS EVENING. SO I WOULD THING THERE SHOULD BE
SOME ISOLATED THUNDERSTORMS WITH THIS AREA SHOWERS TOO.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 345 PM EDT TUE OCT 16 2012
PLUME OF ELEVATED INSTABILITY WITH MID LEVEL LAPSE RATES OF 8-8.5
C/KM OVER IOWA THIS AFTERNOON WILL BE SHIFTING TOWARD SW LWR MI THIS
EVENING... AIDED BY A 45 KT SWLY H8 JET. THAT LOW LEVEL JET IS IN
ADVANCE OF AN H5 SHORTWAVE OVER MN/IA THAT WILL BE PROGRESSING EAST
TOWARD MI. THESE INGREDIENTS SUPPORT A CHANCE OF SHOWERS AND TSTMS
TONIGHT... BUT MOISTURE IS A LIMITING FACTOR WHICH SHOULD LIMIT
COVERAGE. SUSPECT WE WILL BEGIN SEEING SOME HIGHER BASED ACCAS
CLOUDS MOVING IN TOWARD/AFTER SUNSET.
LOOKS LIKE THERE WILL BE A LULL IN PCPN POTENTIAL WEDNESDAY MORNING
INTO THE EARLY AFTERNOON AS THE AFOREMENTIONED SHORTWAVE MOVES OUT
AND THE NEXT WAVE DIVES INTO THE BASE OF THE DIGGING LONGWAVE TROUGH
TO OUR WEST. IT IS THIS WAVE WHICH BRINGS A CATEGORICAL CHANCE FOR
RAIN SHOWERS WEDNESDAY NIGHT. MODELS ARE IN DECENT AGREEMENT ON
TIMING OF THIS FEATURE AND ASSOCIATED SFC FRONT/OCCLUSION PIVOTING
NE THROUGH THE REGION AND PROVIDING A WIDESPREAD SOAKING RAIN.
WHILE RAIN SHOWERS SHOULD END FOR A TIME THURSDAY WITH THE PASSAGE
OF THE COLD FRONT/OCCLUSION... MORE SCATTERED SHOWERS WILL PROBABLY
DEVELOP IN THE AFTERNOON AS THE UPPER LOW AND COLD POOL ALOFT MOVE
IN.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 345 PM EDT TUE OCT 16 2012
RAIN SHOWERS LIKELY TO LINGER FRIDAY BEFORE MOVING OFF FRIDAY NIGHT
AS AN UPPER LOW PROGRESSES TO THE EAST/NORTHEAST. A WEAK RIDGE OF
HIGH PRESSURE WILL MOVE IN FOR THE WEEKEND...WHICH SHOULD KEEP US
MOSTLY DRY SATURDAY THROUGH THE DAY ON MONDAY. AS THE RIDGE OF HIGH
PRESSURE MOVES OFF LATE MONDAY...A MOIST SOUTHWEST FLOW ALOFT WILL
BRING THE POTENTIAL FOR SHOWERS AND MAYBE THUNDERSTORMS LATE MONDAY
NIGHT THROUGH TUESDAY NIGHT.
TEMPERATURES WILL ONLY CLIMB TO AROUND 50 DEGREES ON FRIDAY WITH THE
LINGERING RAIN. GRADUAL WARM UP THROUGH THE WEEKEND...WITH LOWER TO
MID 60S POSSIBLE SUNDAY AND MONDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 657 PM EDT TUE OCT 16 2012
FOR THE MOST PART VFR CONDITIONS SHOULD PREVAIL THROUGH THE TAF
PERIOD. WITH THE SHOWERS AND ISOLATED THUNDERSTORMS ASSOCIATED
WITH THE SHORTWAVE CROSSING CENTRAL LOWER MICHIGAN THIS EVENING
COULD BE BRIEF MVFR VSBY IN HEAVIER SHOWERS. ALSO EXPECT GUSTY
WINDS NEAR SHOWERS AS THERE IS A SIGNIFICANT DRY SUB-CLOUD LAYER.
THIS AREA OF CONVECTION SHOULD BE EAST OF THE TAF SITES BY 06Z OR
SO. THEN PARTLY CLOUD SKIES WITH LAYERED MID CLOUDS SHOULD PREVAIL.
THE NEXT AREA OF RAIN ASSOCIATED WITH THE PRIMARY STORM SYSTEM TO
OUR WEST WILL MOVE IN AFTER 00Z THURSDAY. I EXPECT IFR CIGS/VSBY
AS THAT MOVES THROUGH.
&&
.MARINE...
ISSUED AT 345 PM EDT TUE OCT 16 2012
SMALL CRAFT ADVISORIES CONTINUE AS SOUTHERLY LOW LEVEL JET IMPACTS
LK MI. ADDED WATERSPOUTS TO THE FCST BEHIND THE COLD FRONT THURSDAY
AS UPPER COLD POOL MOVES OVERHEAD.
&&
.HYDROLOGY...
ISSUED AT 345 PM EDT TUE OCT 16 2012
THE BAND OF RAIN ON WEDNESDAY NIGHT COULD PRODUCE WIDESPREAD AMOUNTS
OF 0.50 TO 1.0 INCHES. HOWEVER THIS SHOULD HAVE LITTLE IMPACT ON THE
RIVERS WHICH ARE STILL RUNNING LOW EVEN AFTER LAST WEEKEND/S 1.5 TO
3 INCH RAIN EVENT.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 8 AM EDT THURSDAY FOR LMZ844>849.
&&
$$
UPDATE...WDM
SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...JMM
AVIATION...WDM
HYDROLOGY...MEADE
MARINE...MEADE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
435 PM EDT TUE OCT 16 2012
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 431 PM EDT TUE OCT 16 2012
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW ZONAL FLOW ALF
OVER THE UPR LKS. SHRTWV EMBEDDED WITHIN THIS FLOW IS MOVING THRU
ONTARIO/MN. COMBINATION OF ISENTROPIC ASCENT BEST DEPICTED ON THE
295-300K SFCS/H7 MSTR CNVGC AND UPR DVGC IN RRQ OF 80KT H3 JET MAX
MOVING THRU SE CANADA IS CAUSING AN AREA OF SHRA OVER THE UPR LKS
THIS AFTN. THE PCPN IS MOST WIDESPREAD OVER THE N AND CNTRL CWA...
WITH DRIER AIR BLO H75 DEPICTED ON THE 12Z GRB RAOB AND MORE
IMPRESSIVE ISENTROPIC ASCENT TO THE N RESTRICTING PCPN COVERAGE OVER
THE SCNTRL. TO THE W...DNVA/MID LVL DRYING/LARGER SCALE QVECTOR DVGC
IN THE WAKE OF THE SHRTWV ARE BRINGING A DRYING TREND IN MN...WITH
THE BACK EDGE OF THE RA AREA PUSHING THRU WRN LK SUP EARLY THIS
AFTN. SKIES ARE MOCLR OVER THE NRN PLAINS INTO MN UNDER THE RDG
TRAILING THE SHRTWV. ANOTHER POTENT SHRTWV EMBEDDED IN THE ZONAL
FLOW ALF IS PUSHING INTO THE NRN ROCKIES. THERE WERE SOME 00Z-12Z H3
HGT FALLS IN EXCESS OF 200M ASSOCIATED WITH THIS DISTURBANCE.
MAIN FCST CONCERNS IN THE SHORT TERM REVOLVE ARND PCPN/CLD TRENDS
THRU THE REST OF THIS AFTN THEN TO POTENTIAL FOR FOG TNGT AS DRIER
AIR ALF OVERSPREADS THE AREA. FOCUS FOR WED TURNS TO PCPN CHCS
ASSOCIATED WITH SHRTWV NOW MOVG THRU THE NRN ROCKIES.
LATE TDAY...BEST H7 MSTR TRANSPORT/UPR DVGC INDICATES THE HEAVIER/
MORE WDSPRD SHRA WL SHIFT INTO THE ERN ZNS WHILE DRYING ALF/LARGER
SCALE QVECTOR DVGC ENDS THE PCPN OVER THE W.
TNGT...EXPECT LINGERING SHRA OVER THE E TO END BY MIDNGT WITH THE
PASSAGE OF THE SHRTWV/ARRIVAL OF DRYING ALF AND DNVA/LARGE SCALE
QVECTOR DVGC. GIVEN THE UPR DRYING/CLD TRENDS...EXPECT CLRG TO
OVERSPREAD THE AREA. WITH LINGERING LLVL MSTR...SUSPECT FOG WL DVLP.
WITH A FAIRLY STEADY SSE WIND...THE BEST CHC FOR MORE WDSPRD/DENSER
FOG AND LO CLDS WL BE OVER THE CNTRL ZNS WHERE THAT FLOW UPSLOPES.
TENDED TOWARD THE LO END OF GUIDANCE FOR MIN TEMPS GIVEN EXPECTED
DRYING ALF...BUT STEADY WIND WL RESTRICT THE FALL FM GOING TOO FAR.
WED...THE AT LEAST THE MRNG SHOULD BE DRY WITH LINGERING DRY AIR/UPR
RDG STILL IN PLACE. BUT STRONG SHRTWV NOW MOVING THRU THE NRN
ROCKIES IS FCST TO CLOSE OFF AND DRIFT INTO FAR NW MN BY 00Z THU. AS
SFC LO MOVES INTO NE MN...ATTENDANT COLD FNT IS PROGGED TO APRCH IWD
LATE IN THE DAY. LOOKS LIKE MOST IMPRESSIVE DPVA/DEEP LYR QVECTOR
CNVGC ASSOCIATED WITH THE SHRTWV WL STAY TO THE NW OF THE AREA WHILE
ANOTHER AREA OF DEEP LYR FORCING/UPR DVGC PASSES WELL TO THE S
CLOSER TO UPR JET AXIS/DEEPER MSTR CNVGC. SO OPTED TO GO NO HIER
THAN CHC POPS OVER THE W HALF OF THE CWA IN THE AFTN...WITH DRY WX
EXPECTED OVER THE E HALF CLOSER TO DEPARTING RDG/DRY AIR. ALTHOUGH
FOG MAY LINGER OVER THE CENTRAL WELL THRU THE MRNG WITH PERSISTENT
UPSLOPE SSE FLOW...RETURN OF MORE SUNSHINE IN THE AFTN WITH H85
TEMPS AS HI AS 10-12C SUG TEMPS WL RISE TO WELL ABV NORMAL. COOLER
CONDITIONS ARE LIKELY OVER THE W WHERE THERE WL BE MORE CLD COVER IN
THE AFTN...BUT SOME MRNG SUNSHINE/DOWNSLOPE S WIND WITH LESS FOG
STILL INDICATE A WARM DAY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 431 PM EDT TUE OCT 16 2012
TO BEGIN THE LONG TERM...A DEEP TROF (500MB DEPTH PEAKS THU MORNING
AT 3.5 STANDARD DEVIATIONS FROM THE LONG TERM AVG) WILL BE OVER THE
MID AND UPPER MISSISSIPPI VALLEY. TROF THEN UNRAVELS QUICKLY AND
GETS KICKED NE BY BROAD TROF SETTLING INTO WRN NAMERICA. MEDIUM
RANGE GUIDANCE IS IN POOR AGREEMENT ON THE STRUCTURE/EVOLUTION OF
THE WRN TROF AND STRENGTH/TIMING/TRACKS OF SHORTWAVES EJECTING FROM
TROF. THE GFS RUN-TO-RUN CONSISTENCY FROM LATE WEEKEND INTO EARLY
NEXT WEEK IS IMPROVING WITH LATEST RUNS MORE AGGRESSIVE PUSHING
ENERGY E...FLATTENING DOWNSTREAM RIDGE OVER THE GREAT LAKES/ERN
CONUS AND SHIFTING RIDGE BACK TO THE W. THE ECMWF HAD SHOWN SOMEWHAT
BETTER CONSISTENCY IN DEPICTING A SLOWLY PROGRESSIVE WRN TROF AND A
MORE PRONOUNCED ERN RIDGE THRU EARLY NEXT WEEK. HOWEVER...THE 12Z
ECMWF HAS MADE A BIG SHIFT TOWARD THE GFS IDEA. THRU 12Z MON...THE
GLOBAL GEM/UKMET OFFER OTHER VARYING IDEAS ON THE WRN TROF...BUT
TEND TO LOOK A LITTLE MORE LIKE PREVIOUS ECMWF RUNS. ALL THIS LEADS
TO A VERY LOW CONFIDENCE FCST FOR THE LATTER HALF OF THE LONG TERM
WITH RESPECT TO BOTH TEMPS AND PCPN. GIVEN THE MODEL ISSUES...
TODAY`S LONG TERM FCST WON`T FAVOR ANY SOLUTION IN PARTICULAR THOUGH
IT WOULD SEEM THE 12Z GFS/12Z ECMWF MAY BE WHERE MEDIUM RANGE
GUIDANCE WILL BE HEADING IN UPCOMING RUNS. OVERALL...NEAR NORMAL
TEMPS LATE THIS WEEK SHOULD TREND ABOVE NORMAL BY LATE WEEKEND AND
THEN BEGIN TO FALL BACK CLOSER TO NORMAL. AFTER LINGERING SHRA
CHANCES LATE IN THE WORK WEEK WITH DEPARTING TROF...DEVELOPING GREAT
LAKES/ERN RIDGE SHOULD INITIALLY LEAD TO DRIER WEATHER OVER THE
WEEKEND BEFORE PCPN CHANCES RETURN MON/TUE.
BEGINNING WED NIGHT...TROF WILL BE APPROACHING MAX DEPTH AS 500MB
LOW CLOSES OFF IN THE VCNTY OF NE IA. SFC WAVE WILL DEVELOP/DEEPEN
AND ROTATE THRU ERN WI TOWARD NW WI/WRN UPPER MI OVERNIGHT.
AHEAD OF FRONT/SFC WAVE...WARM CONVEYOR PCPN WILL SWING ACROSS UPPER
MI. NICE DIRECTIONALLY DIFFLUENT UPPER LEVEL FLOW OVERTOP SHARPENING
850MB FRONT WILL AID THE PCPN. LIKELY/CATEGORICAL POPS SPREADING
ACROSS THE AREA APPEARS REASONABLE. CLOUDS/PCPN WILL HOLD MIN TEMPS
IN THE 40S...AND POSSIBLY AROUND 50 E.
WARM CONVEYOR PCPN SHOULD ROTATE OUT OF THE AREA THU...BUT DEEP
CYCLONIC FLOW AND INDICATIONS OF SHORTWAVE PIVOTING AROUND MID LEVEL
LOW TOWARD UPPER MI WILL WORK TO KEEP PCPN CHANCES OVER THE AREA
THRU THE DAY. ABUNDANT CLOUD COVER AND WEAK CAA WILL LIMIT DIURNAL
TEMP RISE. EXPECT HIGHS IN THE UPPER 40S TO MID 50S.
THU NIGHT/FRI...ENTIRE SYSTEM WEAKENS RATHER QUICKLY AND FOCUSED
PCPN SHOULD DIMINISH AS LOW/MID LEVEL WIND FIELDS WEAKEN
DRAMATICALLY. IN FACT...MUCH OF THE GUIDANCE SUGGESTS A TREND TOWARD
MOSTLY DRY LATER THU NIGHT INTO FRI. HOWEVER...WHILE ORGANIZED PCPN
AREAS WILL DIMINISH THU NIGHT...PROXIMITY OF THE CENTER OF WEAKENING
MID LEVEL LOW SUGGESTS MAINTAINING CHC/SLIGHT CHC POPS THU
NIGHT/FRI. MAY END UP BEING MORE OF A DRIZZLE SITUATION WITH PATCHY
-RA. DIURNAL TEMP SWING THU NIGHT/FRI SHOULD CONTINUE TO BE LIMITED
BY CLOUDS AND ALSO BY LITTLE TEMP ADV.
AS WEAKENING SYSTEM BEGINS TO ACCELERATE TO THE NE SAT...WILL OPT
FOR A DRY DAY. BEST SHOT FOR A DRY DAY WILL BE SUN AS AMPLIFYING
RIDGE AXIS DOWNSTREAM OF DEVELOPING WRN TROF SHIFTS ACROSS THE UPPER
LAKES. SUN WILL BE THE WARMEST DAY...WITH MID 50S E AND PERHAPS
AROUND 60F OVER THE W
AS MENTIONED ABOVE...THERE IS VERY LOW CONFIDENCE IN FCST FOR EARLY
NEXT WEEK. EXPECT A CHC OF PCPN AT SOME POINT SUN NIGHT INTO TUE AS
COLD FRONT SLIPS THRU THE AREA. THE 12Z ECMWF/GFS SUGGEST LIMITED
PCPN CHC THAT WILL BE CONFINED MAINLY TO MON OVER THE SCNTRL AND E.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 122 PM EDT TUE OCT 16 2012
EXPECT STEADY RA TO END W-E THIS AFTN AS DRY AIR OVERSPREADS THE UPR
GRT LKS...BUT NOT BEFORE A PERIOD OF MVFR/IFR CONDITIONS IMPACT CMX
AND SAW. ALTHOUGH CONDITIONS SHOULD BE VFR INTO EARLY EVNG AFTER ANY
PCPN ENDS...EXPECT SOME FOG/LO CLD TO DVLP OVERNGT WITH NOCTURNAL
COOLING OF THE FAIRLY MOIST LLVLS UNDER THE DRYING ALF. THE BEST CHC
FOR IFR AND EVEN LIFR CONDITIONS WL BE AT SAW...WITH FAVORABLE
UPSLOPE SSE WIND. ONSET OF DAYTIME HEATING/MIXING ON WED WL BREAK UP
ANY FOG/LO CLD THAT DEVELOPS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 431 PM EDT TUE OCT 16 2012
EXPECT S WINDS UP TO 25-30 KTS OVER THE E HALF TO DIMINISH A BIT
TONIGHT WITH THE ARRIVAL OF A WEAKER PRES GRADIENT. SE WINDS UP TO
25 KTS WILL CONTINUE ON WED IN ADVANCE OF AN APPROACHING DEEP LO
PRES CENTER. THE STRONGEST WINDS WILL BE OVER THE E HALF AGAIN WHERE
THE TERRAIN TENDS TO ENHANCE THESE WINDS.
DEEPENING SFC LOW ROTATING NW THRU NRN WI WED NIGHT WILL RESULT IN
AN INCREASE IN E TO SE WINDS ACROSS LAKE SUPERIOR. NOT OUT OF THE
QUESTION THAT SOME GALE FORCE GUSTS COULD DEVELOP LATE IN THE NIGHT
FROM AROUND WHITEFISH PT TO AROUND ISLE ROYALE. WINDS WILL THEN
DIMINISH DURING THE DAY THU AS LOW PRES WEAKENS. BY THU AFTN...WINDS
SHOULD BE UNDER 15KT OVER WRN LAKE SUPERIOR AND DOWN TO 15 TO 25KT
OVER CNTRL AND ERN LAKE SUPERIOR. BEYOND THU...NO SIGNIFICANT
WEATHER SYSTEMS ARE EXPECTED TO AFFECT THE UPPER LAKES THRU THE
WEEKEND. IN FACT...WEAK PRES GRADIENT MAY LEAD TO A PERIOD OF LIGHT
WINDS UNDER 15KT OVER MUCH OF LAKE SUPERIOR FRI THRU SUN.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...NONE.
LAKE SUPERIOR...NONE.
LAKE MICHIGAN...NONE.
&&
$$
SHORT TERM...KC
LONG TERM...ROLFSON
AVIATION...KC
MARINE...KC/ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
123 PM EDT TUE OCT 16 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 622 AM EDT TUE OCT 16 2012
WV IMAGERY AND RUC ANALYSIS SHOWS A WELL-DEFINED SHORTWAVE MOVING
EAST THROUGH SOUTH DAKOTA. STRONG WAA/ISENTROPIC LIFT AHEAD OF THIS
FEATURE AND LOWERING CONDENSATION PRES DEFICITS HAVE ALLOWED FOR AN
AREA OF LIGHT RAIN TO DEVELOP OVER THE NRN HALF OF MN STRETCHING
INTO FAR NRN WI AND WRN UPR MI. INITIAL VERY DRY AIR AT LOW-LVLS AS
NOTED ON 00Z KMPX AND KINL SNDGS HAS KEPT RAIN LIGHT AND REPORTED
CIGS THUS FAR WITH RAIN HAVE BEEN HIGH-BASED...GENERALLY ABV 5KFT.
WAA MID-HIGH CLOUDS SPREADING INTO UPPER MI HAVE BROUGHT TEMPS UP
ABV FREEZING AT MOST LOCATIONS EARLY THIS MORNING AFTER CHILLY UPPER
20S LOWS REACHED EARLIER IN THE EVENING AT MANY CENTRAL AND ERN
LOCATIONS.
AS THE 850-700 MB WARM FRONT NOW REACHING INTO THE WRN CWA MOVES
EAST THROUGH THE AREA TODAY...PCPN WILL SPREAD EAST ACROSS THE CWA.
LIKELY-CATEGORICAL POPS ARE WARRANTED...ESPECIALLY ACROSS THE NRN
TIER AND ERN COUNTIES WHERE THE STRONGEST ISENTROPIC LIFT AND BEST
LLVL MOISTURE TRANSPORT IS LOCATED ALONG/AHEAD OF THE ADVANCING 850
MB WARM FRONT...AS PROGGED BY 00-06Z MODELS. BELIEVE INITIALLY DRY
LOW-LVLS MAY NEGATIVELY IMPACT PCPN AMOUNTS...KEEPING RAINFALL
CLOSER TO STINGIER NAM/WRF-ARW AMOUNTS OF .1-.2 INCH NORTH TO LESS
THAN .1 INCH SOUTH. MODELS HAVE BEEN CONSISTENT WITH THE PCPN ENDING
OVER THE WEST BY EARLY AFTERNOON AND OVER THE EASTERN COUNTIES IN
TUE EVENING AS Q-VECT DIV/SUBSIDENCE SPREADS IN FROM THE WEST IN THE
WAKE OF THE SHORTWAVE AND ASSOC WARM FRONT. LOW CLOUDS/FOG WILL
REMAIN A CONCERN LATE TONIGHT DUE TO CLEARING SKIES FROM WEST AND
LEFTOVER LOW LEVEL MOISTURE FROM AFTN/EVENING RAINFALL SO HAVE
MAINTAINED MENTION OF FOG...ESPECIALLY CENTRAL AND EAST WHERE
UPSLOPE/ONSHORE FLOW OFF LAKE MI COULD ENHANCE FOG CHCS.
WAA WILL DRAW ENOUGH WARM AIR INTO THE REGION TO PUSH MAX READINGS
TODAY INTO UPPER 50S WEST WHILE TEMPS LINGER AROUND 50 OVER THE
EAST. TEMPS SHOULD STAY RELATIVELY MILD TONIGHT (IN THE 40S) AS WE
REMAIN IN WARM SECTOR AHEAD OF DEEPENING SFC LOW NR LAKE WINNIPEG
AND OCCLUDED FRONT STRETCHING INTO THE PLAINS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 622 AM EDT TUE OCT 16 2012
MAJORITY OF FOCUS IN THE LONG TERM IS ON DEEP UPPER TROUGH THAT DIGS
INTO CENTRAL CONUS WEDNESDAY AND THURSDAY. ASSOCIATED SFC TROUGH IS
INITIALLY STRUNG OUT FROM SOUTHERN SASKATCHEWAN AND MANITOBA INTO
MIDDLE MISSISSIPPI RIVER VALLEY ON WEDNESDAY...THEN PHASES INTO A
985-990MB SFC LOW OVER UPPER GREAT LAKES BY THURSDAY MORNING. RAIN
CHANCES ON WEDNESDAY DRIVEN BY BROAD UPPER DIFFLUENCE BTWN THE CNTRL
CONUS UPR LOW AND RIDGE OVER THE NORTHEAST CONUS. MOISTURE ADVECTION
AT H85 ALSO A FACTOR. GOING WITH PREFERRED ECMWF MODELS DEPICTION...
STRONGER UPPER FORCING /MID-LEVEL HEIGHT FALLS AND H85-H7
FRONTOGENESIS/ HOLDS OFF OVR UPR MICHIGAN UNTIL LATER WEDNESDAY AFTN
OVER WESTERN CWA AND ACROSS REST OF CWA ON WEDNESDAY NIGHT. MAX
TEMPS ON WEDNESDAY REMAIN TRICKY PROPOSITION AS IT IS FEASIBLE THERE
COULD BE SOME SUNSHINE THROUGH MIDDAY FOR PORTIONS OF CWA /DEPENDS
ON HOW QUICKLY ANY FOG/LOW CLOUDS GET OUT OF THE WAY IN THE MORNING/
BUT GIVEN ANY SUNSHINE...TEMPS ALOFT ARE PRETTY WARM /H85 TEMPS
PUSHING +10C AND H925 TEMPS OVR +10C/ SO WOULD NOT TAKE MUCH MIXING
TO ALLOW TEMPS TO PUSH PAST 60 DEGREES. KEPT TEMPS OVER FAR WEST
COOLER WITH MORE CLOUDS AND PRECIP EXPECTED BUT TEMPS ELSEWHERE
SHOULD TOP OUT IN THE 60S WHICH WOULD BE THE WARMEST DAY SEEN SINCE
OCTOBER 4TH WHEN TEMPS REACHED UPPER 60S.
NO REAL CHANGE TO PREVIOUS THINKING IN THAT WEDNESDAY NIGHT TURNS
OUT TO BE WET NIGHT OVER CWA. SWATH OF WARM CONVEYOR MOISTURE AND A
BIT OF A TROWAL REGION PIVOT ACROSS CWA AS SFC LOW OCCLUDES WHICH
PUTS AREA IN REGION OF MORE STEADY RAIN MOST OF THE NIGHT. HAVE
LINGERED HIGHER POPS ON THURSDAY OVER KEWEENAW AS THAT AREA REMAINS
ON SOUTHERN EDGE OF H85 THERMAL GRADIENT AND WITHIN H3 JET CORE.
SHORTWAVE ROTATING NORTH IN PERIFERY OF BROAD UPPER LOW MAY BRING
INCREASE TO POPS FOR MUCH OF CWA THURSDAY AFTN/EVENING. PVA FM THE
WAVE AND MORE PERSISTENT LOW-LEVEL MOISTURE ADVECTION IS FORECAST
OVER THE EAST...ALONG WITH SOME ELEVATED INSTABILITY AS SI/S FALL
TOWARD 0C. ANY DETAIL IS REALLY A ROUGH GUESS AS SENSIBLE WEATHER
WILL BE ALTERED WITH JUST A SLIGHT SHIFT IN THE UPR LOW CENTER. DRY
AIR INTRUSION THAT MODELS HAVE HINTED AT FOR A WHILE SHOWS UP LATER
THURSDAY NIGHT INTO FRIDAY. EXPECT STEADIER PRECIP TO DIMINISH BY
THAT TIME...THOUGH CERTAINLY COULD SEE LOW CLOUDS AND MAYBE SOME
LIGHTER PRECIP/DRIZZLE LINGER. CHANCES FOR MORE SIGNIFICANT PRECIP
WOULD BE ENHANCED WHERE THE LOW-LEVEL WINDS ARE MOST ONSHORE AND/OR
PROVIDE MOST UPSLOPE LIFT.
LOW THEN WOBBLES SOUTH/SOUTHEAST LATER FRIDAY AND IS FINALLY KICKED
OFF TOWARD EASTERN CANADA/NEW ENGLAND THROUGH THE UPCOMING WEEKEND.
AFTER SOME WARMER THAN NORMAL TEMPS THROUGH MIDWEEK...TEMPS
GRADUALLY TREND SLIGHTLY BLO NORMAL BY FRIDAY AS COLD AIR ADVECTION
AFFECTS THE UPR LAKES REGION. INTO THE WEEKEND...HAVE SIDED WITH
MORE CONSISTENT ECMWF THAT SHOWS A GENERALLY DRY WEEKEND AS UPR
LAKES IS BTWN EXITING UPR LOW AND ANOTHER TROUGH SLIDING TOWARD
NORTHERN PLAINS BY SUNDAY. SINCE SFC TROUGH DEVELOPS OVER THE PLAINS
BY SUNDAY SW WINDS SHOULD PUSH TEMPS BACK TOWARD NORMAL THROUGH THE
WEEKEND IF NOT SLIGHTLY ABOVE NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 122 PM EDT TUE OCT 16 2012
EXPECT STEADY RA TO END W-E THIS AFTN AS DRY AIR OVERSPREADS THE UPR
GRT LKS...BUT NOT BEFORE A PERIOD OF MVFR/IFR CONDITIONS IMPACT CMX
AND SAW. ALTHOUGH CONDITIONS SHOULD BE VFR INTO EARLY EVNG AFTER ANY
PCPN ENDS...EXPECT SOME FOG/LO CLD TO DVLP OVERNGT WITH NOCTURNAL
COOLING OF THE FAIRLY MOIST LLVLS UNDER THE DRYING ALF. THE BEST CHC
FOR IFR AND EVEN LIFR CONDITIONS WL BE AT SAW...WITH FAVORABLE
UPSLOPE SSE WIND. ONSET OF DAYTIME HEATING/MIXING ON WED WL BREAK UP
ANY FOG/LO CLD THAT DEVELOPS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 622 AM EDT TUE OCT 16 2012
LOW PRESSURE TROUGH APPROACHING FROM THE NRN PLAINS WILL RESULT
IN SOUTH WINDS OF 15 TO 25 KT WITH AREAS TO NEAR 30 KT OVER ERN LAKE
SUPERIOR THIS AFTERNOON AND EVENING. A DEEPER LOW PRESSURE SYSTEM
MOVING INTO THE UPPER GREAT LAKES ON THURSDAY COULD CAUSE AN
INCREASE IN ERLY WINDS TO 30 KT LATE WED NIGHT AND EARLY
THURSDAY. OTHERWISE...WINDS IN THE VICINITY OF THE LOW SHOULD
GENERALLY REMAIN LESS THAN 20 KTS WEDNESDAY THROUGH SATURDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...KC
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
423 PM EDT TUE OCT 16 2012
.SYNOPSIS...
SURFACE HIGH PRESSURE BUILDS INTO THE NORTH COUNTRY TONIGHT BRINGING
DECREASING CLOUDINESS AND LIGHT WINDS. THE HIGH PRESSURE AREA MOVES
EAST INTO THE GULF OF MAINE DURING WEDNESDAY AFTERNOON...AND WILL
BRING DRY WEATHER WEDNESDAY AND THURSDAY...WITH A GRADUAL
MODERATION OF TEMPERATURES. A LARGE UPPER LOW PRESSURE SYSTEM AND
ASSOCIATED OCCLUDED FRONT SHOULD BRING A PERIOD OF RAINFALL TO THE
NORTH COUNTRY THURSDAY NIGHT INTO FRIDAY MORNING.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
AS OF 245 PM EDT TUESDAY...SFC RIDGE AXIS SHIFTS EWD FROM THE ERN
GREAT LAKES REGION AND CRESTS OVER THE NORTH COUNTRY OVERNIGHT.
INVERSION NEAR 3 KFT KEEPING SHALLOW STRATUS LAYER IN PLACE LATE
THIS AFTN...BUT ANTICIPATE CLEARING AREAWIDE DURING THE EVENING
HRS WITH DRYING/SUBSIDENCE. LOOKING FOR MOSTLY CLEAR SKIES FOR THE
OVERNIGHT...ALTHOUGH A FEW MID-LEVEL CLOUDS (8-12 KFT) ASSOCIATED
WITH UPSTREAM SHORTWAVE TROUGH ACROSS THE UPR MS RIVER VALLEY/WRN
GREAT LAKES REGION WILL STREAM RAPIDLY EWD AND REACH NRN NY TOWARD
09Z. HAVE INDICATED SOME SCATTERED CLOUDS IN ASSOCIATION WITH THIS
FEATURE TOWARD DAYBREAK. SHOULD BE A PERIOD OF GOOD RADIATIONAL
COOLING WITH LOW TEMPERATURES GENERALLY IN THE UPPER 20S TO LOWER
30S. NWLY GRADIENT FLOW WITH WINDS 10-20 MPH AND A FEW GUSTS TO 30
MPH WILL QUICKLY ABATE THIS EVENING WITH BOUNDARY LAYER
STABILIZATION. ANY LINGERING SPRINKLES ACROSS THE NORTHEAST
KINGDOM WILL END LATE THIS AFTN/EARLY THIS EVENING WITH
DISSIPATION OF LOW CLOUD DECK WITH NIL POPS 00-12Z.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
AS OF 245 PM EDT TUESDAY...TRANQUIL WX UNTIL THURSDAY NIGHT. SFC RIDGE
AXIS DRIFTS EWD INTO THE GULF OF MAINE LATE WEDNESDAY WITH A
LIGHT 5-8 MPH SLY RETURN FLOW DEVELOPING. 850MB TEMPS MODERATE
NICELY TO +7C TO +8C BY 21Z WEDNESDAY. MID-LEVEL WAA AND
CONTINUATION OF RELATIVELY HIGH MID-LEVEL RH SUGGESTS PERIODS OF
MID-LEVEL CLOUDS DURING THE DAY WEDNESDAY. ALL IN ALL...WILL BE
PARTLY CLOUDY WITH PERIODS OF FILTERED SUN. CLOUDS SHOULDN/T
SIGNIFICANTLY IMPACT HIGH TEMPERATURES...SO STAYED CLOSE TO MOS
WITH MAX TEMPS IN THE MID-UPR 50S (OR ABOUT 10F HIGHER THAN
TUESDAY/S HIGHS).
VARIABLE MID-LEVEL CLOUDINESS CONTINUES WEDNESDAY NIGHT WITH LIGHT
SOUTH WINDS CONTINUING IN THE CHAMPLAIN VALLEY. SOME CLOUDS AND
MODIFYING AIR MASS WILL KEEP TEMPS A BIT WARMER COMPARED TO TUESDAY
NIGHT WITH LOWS WED NGT MID 30S TO LWR 40S.
THURSDAY LOOKS MILDER STILL AS MID-LEVEL HEIGHTS BUILD IN ADVANCE OF
LARGE-SCALE/SLOW-MOVING UPR LOW ACROSS THE MID-UPR MS RIVER VALLEY.
HIGHS WILL REACH THE MID-UPR 60S...WARMEST IN THE CHAMPLAIN AND ST.
LAWRENCE RIVER VALLEYS. SOUTH WINDS CONTINUE WITH SFC HIGH WELL
OFFSHORE AND VERTICALLY STACKED LOW OVER THE WRN GREAT LAKES. MAY
SEE AN INCREASE IN HIGH CLOUDS LATE IN THE DAY - ESPECIALLY ACROSS
NRN NY.
LEADING FRONTAL RAIN BAND WITH LARGE-SCALE OCCLUSION SWINGS INTO THE
FORECAST AREA DURING THURSDAY NIGHT BASED ON 12Z GFS/SREF/NAM. THE
ECMWF CONTINUES TO BE SLOWER WITH THE EVOLUTION OF THIS
SYSTEM...AND COULD SUGGEST A SLOWER PCPN ARRIVAL TIME. AT THIS
POINT...WILL INDICATE CLOUDY SKIES/LIKELY POPS WITH A STEADY
STRATIFORM RAIN DEVELOPING. QPF POTL 0.25-0.50"...THOUGH LIKELY
LESS ACROSS FAR ERN/NERN VT WITH LATER ARRIVAL TIME OF PRECIP.
WILL BE A MILD NIGHT WITH SE/SOUTH WINDS AND CLOUDS AREAWIDE. MAY
SEE SOME GUSTY DOWNSLOPE WINDS ALONG THE WESTERN SLOPES OF THE
GREEN MTNS (UP TO 35 MPH BASED ON PRESENT INDICATIONS) AND WILL BE
SOMETHING TO MONITOR AS DETAILS BECOME MORE APPARENT. SHOULD SEE
RATHER UNIFORM AND MILD LOW TEMPS EXPECTED IN THE UPR 40S TO LWR
50S.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 430 PM EDT TUESDAY...FCST FOCUS WL BE EVOLUTION/MOVEMENT OF
FULL LATITUDE CLOSED MID/UPPER LVL CIRCULATION ACRS THE EASTERN
CONUS AND IMPACTS TO OUR CWA. OVERALL MODELS IN GOOD AGREEMENT
WITH LARGE SCALE CLOSED SYSTEM SHIFTING FROM THE NORTHERN PLAINS
INTO THE OHIO VALLEY BY FRIDAY AND INTO EASTERN CANADA BY THE
WEEKEND. HOWEVER...PLENTY OF UNCERTAINTY WITH REGARDS TO TIMING OF
INDIVIDUAL S/W`S AND RIBBONS OF ENHANCED 850 TO 500MB RH...WHICH
RESULTS IN UNCERTAINTY IN PRECIP TIMING/PLACEMENT FOR FRIDAY INTO
THIS UPCOMING WEEKEND. GFS/SREF/GEM AND ECMWF ALL SHOW A SURGE OF
>1.0" PWS AHEAD OF OCCLUDED TYPE BOUNDARY ON FRIDAY INTO
SATURDAY...ASSOCIATED WITH POTENT LOW/MID LVL JET...AND STRONG
ULVL DIVERGENCE. GIVEN AVAILABLE MOISTURE/DYNAMICS WL CONT TO
MENTION HIGH LIKELY POPS ATTM FOR FRIDAY INTO SAT...BUT 6 TO 10 HR
WINDOW FOR HEAVIEST QPF IS DIFFICULT TO TIME. GIVEN THE DOWNSTREAM
BLOCKING FROM WESTERN ATLANTIC MID/UPPER LVL RIDGE AND DEEP CLOSED
CUTOFF CIRCULATION...FEEL A SLOWER/WETTER AND WARMER SOLUTION OF
THE GEM/ECMWF LOOKS REASONABLE AND WL TREND TWD. THIS SUPPORTS
ABOVE NORMAL TEMPS FOR FRI THRU SAT...WITH A COOLING TREND BY
SUNDAY...AS LLVL CAA DEVELOPS BEHIND DEPARTING CLOSED CIRCULATION.
IN ADDITION...WL CONT TO MENTION CHC POPS FOR SUNDAY ASSOCIATED
WITH UPSLOPE FLW AND LLVL CAA. THIS WL PROBABLY NEED TO BE
ADJUSTED UPWARD AS CONFIDENCE INCREASES WITH REGARDS TO AMOUNT OF
MOISTURE AND UPSLOPE LIFT. MID/UPPER LVL RIDGE REDEVELOPS FOR
EARLY NEXT WEEK...WITH ABOVE NORMAL TEMPS AND SOME DRYING.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
THROUGH 18Z WEDNESDAY...AVIATION CHALLENGE IS TIMING OF CLOUDS
DISSIPATING ACRS OUR TAF SITES THIS AFTN/EVENING. CRNT SFC
ANALYSIS SHOWS CYCLONIC UPSLOPE FLW ACRS OUR CWA WITH LOW PRES
LOCATED EAST OF CARIBOU MAINE THIS AFTN. THIS LLVL UPSLOPE
FLW...COMBINED WITH MOISTURE TRAPPED BLW TEMP INVERSION HAS RESULTED
PLENTY OF CLOUDS WITH MVFR CONDITIONS AT MOST SITES. NAM/GFS
VERTICAL SOUNDINGS ARE TOO QUICK AT ERODING THE CLOUDS...GIVEN
MOISTURE/WIND DIRECTION...WL TREND TOWARD THE LATEST RAP
SOUNDINGS. THESE SHOW MVFR BCMG VFR CONDITIONS BY 21Z AT
PBG/BTV/RUT/MSS AND AFT 00Z AT MPV/SLK WITH NW WINDS BECMG
LIGHT/VARIABLE TWD SUNSET. INTERESTING RAP SOUNDINGS CONT TO SHOW
VERY SHALLOW RH PROFILES OVERNIGHT AT SLK/MPV...BUT THINKING WITH
SFC HIGH PRES/SUBSIDENCE DEPTH OF MOISTURE WL NOT BE ENOUGH TO
PRODUCE CLOUDS...BUT SATL TRENDS WL NEED TO BE MONITORED.
OUTLOOK 18Z WEDNESDAY THROUGH SATURDAY...
SFC HIGH PRES WITH VFR CONDITIONS PREVAIL THRU 00Z FRIDAY...BEFORE
NEXT SYSTEM PRODUCE WIDESPREAD RAIN WITH MVFR CONDITIONS BTWN 06Z
FRIDAY AND 18Z FRIDAY. IN ADDITION...SOME GUSTY SOUTH TO SOUTHEAST
WINDS WL BE POSSIBLE...ESPECIALLY AT RUT...ALONG WITH AREAS OF LLVL
WIND SHEAR AND TURBULENCE THURS NIGHT/FRIDAY MORNING. AREAS OF
SCATTERED SHOWERS WITH MVFR AND BRIEF PERIODS OF IFR AT SLK/MPV WL
BE POSSIBLE FRIDAY AFTN INTO SAT....AS SFC LOW PRES CONTS TO
IMPACT OUR TAF SITES.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS
SHORT TERM...BANACOS
LONG TERM...TABER
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
252 PM EDT TUE OCT 16 2012
.SYNOPSIS...
SURFACE HIGH PRESSURE BUILDS INTO THE NORTH COUNTRY TONIGHT BRINGING
DECREASING CLOUDINESS AND LIGHT WINDS. THE HIGH PRESSURE AREA MOVES
EAST INTO THE GULF OF MAINE DURING WEDNESDAY AFTERNOON...AND WILL
BRING DRY WEATHER WEDNESDAY AND THURSDAY...WITH A GRADUAL
MODERATION OF TEMPERATURES. A LARGE UPPER LOW PRESSURE SYSTEM AND
ASSOCIATED OCCLUDED FRONT SHOULD BRING A PERIOD OF RAINFALL TO THE
NORTH COUNTRY THURSDAY NIGHT INTO FRIDAY MORNING.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
AS OF 245 PM EDT TUESDAY...SFC RIDGE AXIS SHIFTS EWD FROM THE ERN
GREAT LAKES REGION AND CRESTS OVER THE NORTH COUNTRY OVERNIGHT.
INVERSION NEAR 3 KFT KEEPING SHALLOW STRATUS LAYER IN PLACE LATE
THIS AFTN...BUT ANTICIPATE CLEARING AREAWIDE DURING THE EVENING
HRS WITH DRYING/SUBSIDENCE. LOOKING FOR MOSTLY CLEAR SKIES FOR THE
OVERNIGHT...ALTHOUGH A FEW MID-LEVEL CLOUDS (8-12 KFT) ASSOCIATED
WITH UPSTREAM SHORTWAVE TROUGH ACROSS THE UPR MS RIVER VALLEY/WRN
GREAT LAKES REGION WILL STREAM RAPIDLY EWD AND REACH NRN NY TOWARD
09Z. HAVE INDICATED SOME SCATTERED CLOUDS IN ASSOCIATION WITH THIS
FEATURE TOWARD DAYBREAK. SHOULD BE A PERIOD OF GOOD RADIATIONAL
COOLING WITH LOW TEMPERATURES GENERALLY IN THE UPPER 20S TO LOWER
30S. NWLY GRADIENT FLOW WITH WINDS 10-20 MPH AND A FEW GUSTS TO 30
MPH WILL QUICKLY ABATE THIS EVENING WITH BOUNDARY LAYER
STABILIZATION. ANY LINGERING SPRINKLES ACROSS THE NORTHEAST
KINGDOM WILL END LATE THIS AFTN/EARLY THIS EVENING WITH
DISSIPATION OF LOW CLOUD DECK WITH NIL POPS 00-12Z.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
AS OF 245 PM EDT TUESDAY...TRANQUIL WX UNTIL THURSDAY NIGHT. SFC RIDGE
AXIS DRIFTS EWD INTO THE GULF OF MAINE LATE WEDNESDAY WITH A
LIGHT 5-8 MPH SLY RETURN FLOW DEVELOPING. 850MB TEMPS MODERATE
NICELY TO +7C TO +8C BY 21Z WEDNESDAY. MID-LEVEL WAA AND
CONTINUATION OF RELATIVELY HIGH MID-LEVEL RH SUGGESTS PERIODS OF
MID-LEVEL CLOUDS DURING THE DAY WEDNESDAY. ALL IN ALL...WILL BE
PARTLY CLOUDY WITH PERIODS OF FILTERED SUN. CLOUDS SHOULDN/T
SIGNIFICANTLY IMPACT HIGH TEMPERATURES...SO STAYED CLOSE TO MOS
WITH MAX TEMPS IN THE MID-UPR 50S (OR ABOUT 10F HIGHER THAN
TUESDAY/S HIGHS).
VARIABLE MID-LEVEL CLOUDINESS CONTINUES WEDNESDAY NIGHT WITH LIGHT
SOUTH WINDS CONTINUING IN THE CHAMPLAIN VALLEY. SOME CLOUDS AND
MODIFYING AIR MASS WILL KEEP TEMPS A BIT WARMER COMPARED TO TUESDAY
NIGHT WITH LOWS WED NGT MID 30S TO LWR 40S.
THURSDAY LOOKS MILDER STILL AS MID-LEVEL HEIGHTS BUILD IN ADVANCE OF
LARGE-SCALE/SLOW-MOVING UPR LOW ACROSS THE MID-UPR MS RIVER VALLEY.
HIGHS WILL REACH THE MID-UPR 60S...WARMEST IN THE CHAMPLAIN AND ST.
LAWRENCE RIVER VALLEYS. SOUTH WINDS CONTINUE WITH SFC HIGH WELL
OFFSHORE AND VERTICALLY STACKED LOW OVER THE WRN GREAT LAKES. MAY
SEE AN INCREASE IN HIGH CLOUDS LATE IN THE DAY - ESPECIALLY ACROSS
NRN NY.
LEADING FRONTAL RAIN BAND WITH LARGE-SCALE OCCLUSION SWINGS INTO THE
FORECAST AREA DURING THURSDAY NIGHT BASED ON 12Z GFS/SREF/NAM. THE
ECMWF CONTINUES TO BE SLOWER WITH THE EVOLUTION OF THIS
SYSTEM...AND COULD SUGGEST A SLOWER PCPN ARRIVAL TIME. AT THIS
POINT...WILL INDICATE CLOUDY SKIES/LIKELY POPS WITH A STEADY
STRATIFORM RAIN DEVELOPING. QPF POTL 0.25-0.50"...THOUGH LIKELY
LESS ACROSS FAR ERN/NERN VT WITH LATER ARRIVAL TIME OF PRECIP.
WILL BE A MILD NIGHT WITH SE/SOUTH WINDS AND CLOUDS AREAWIDE. MAY
SEE SOME GUSTY DOWNSLOPE WINDS ALONG THE WESTERN SLOPES OF THE
GREEN MTNS (UP TO 35 MPH BASED ON PRESENT INDICATIONS) AND WILL BE
SOMETHING TO MONITOR AS DETAILS BECOME MORE APPARENT. SHOULD SEE
RATHER UNIFORM AND MILD LOW TEMPS EXPECTED IN THE UPR 40S TO LWR
50S.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 400 AM EDT TUESDAY...A LOT OF UNCERTAINTY EXISTS IN THE
EXTENDED PORTION OF THE FORECAST DUE TO DIFFERING MODEL SOLUTIONS
IN REGARDS TO THE OVERALL SYNOPTIC PATTERN FROM THURSDAY NIGHT
ONWARDS. FORECASTER CONFIDENCE IS LOW.
RELIABLE MEDIUM/LONG TERM MODELS OF THE GFS AND ECMWF SEEM TO
CONTINUE TO BE AT ODDS WITH THE OVERALL HANDLING OF A POTENT LOW
PRESSURE SYSTEM MOVING OUT OF THE GREAT LAKES REGION THURSDAY NIGHT.
OVERALL...THERE IS A GENERAL AGREEMENT IN REGARDS TO THE TRACK FROM
THE GREAT LAKES NORTHEASTWARD THROUGH THE SAINT LAWRENCE VALLEY AND
INTO CENTRAL QUEBEC...BUT THERE ARE HUGE DIFFERENCES IN TIMING. GFS
IS MUCH MORE PROGRESSIVE MOVING THE LOW NORTH OF THE CWA BY SATURDAY
NIGHT...WHILE THE ECMWF LAGS BEHIND BY A GOOD 24 HOURS. HARD TO
PREDICT WHICH IS RIGHT AT THIS POINT...BUT HAVE LEANED TOWARDS THE
ECMWF SOLUTION BASED ON BETTER PERFORMANCE OVER THE LAST WEEK OR SO.
THAT SAID...EXPECTING TO SEE WIDESPREAD RAIN ACROSS THE REGION
DEVELOPING LATE THURSDAY NIGHT...AND CONTINUING THROUGH FRIDAY NIGHT
AS LOW PRESSURE SLOWLY SHIFTS EASTWARD THROUGH THE GREAT LAKES.
COULD BE LOOKING AT SOME DECENT RAINFALL AMOUNTS WITH A STRONG
MOISTURE FEED OFF THE SOUTHEAST COAST...AND THIS WILL NEED TO BE
MONITORED FOR POSSIBLE FLOOD POTENTIAL AS SOIL MOISTURE IS RUNNING
HIGH FROM ABOVE NORMAL PRECIP SO FAR THIS MONTH. STRONG S/SW FLOW
WILL KEEP TEMPS RATHER MILD ACROSS THE REGION WITH LOWS IN THE 50S
AND HIGHS IN THE 60S. S/SW FLOW CONTINUES ON SATURDAY WITH CONTINUED
HIGH CHANCES FOR SHOWERS AS THE LOW SHIFTS NORTHEAST THROUGH THE
SAINT LAWRENCE VALLEY AND TRACKS A COLD FRONT ACROSS THE REGION.
WINDS SHIFT TO THE W/NW POST FRONTAL PASSAGE AND CONTINUED
CLOUDINESS IS LIKELY SATURDAY NIGHT WITH AMPLE WRAP-AROUND MOISTURE
KEEPING SOME SHOWERS AROUND. BY SUNDAY MORNING...HIGH AMPLITUDE
RIDGE BEGINS TO BUILD INTO THE REGION...AND WILL DOMINATE THE NORTH
COUNTRYS WEATHER THROUGH THE REMAINDER OF THE FORECAST PERIOD WITH
DRY AND SEASONAL CONDITIONS EXPECTED.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
THROUGH 18Z WEDNESDAY...AVIATION CHALLENGE IS TIMING OF CLOUDS
DISSIPATING ACRS OUR TAF SITES THIS AFTN/EVENING. CRNT SFC
ANALYSIS SHOWS CYCLONIC UPSLOPE FLW ACRS OUR CWA WITH LOW PRES
LOCATED EAST OF CARIBOU MAINE THIS AFTN. THIS LLVL UPSLOPE
FLW...COMBINED WITH MOISTURE TRAPPED BLW TEMP INVERSION HAS RESULTED
PLENTY OF CLOUDS WITH MVFR CONDITIONS AT MOST SITES. NAM/GFS
VERTICAL SOUNDINGS ARE TOO QUICK AT ERODING THE CLOUDS...GIVEN
MOISTURE/WIND DIRECTION...WL TREND TOWARD THE LATEST RAP
SOUNDINGS. THESE SHOW MVFR BCMG VFR CONDITIONS BY 21Z AT
PBG/BTV/RUT/MSS AND AFT 00Z AT MPV/SLK WITH NW WINDS BECMG
LIGHT/VARIABLE TWD SUNSET. INTERESTING RAP SOUNDINGS CONT TO SHOW
VERY SHALLOW RH PROFILES OVERNIGHT AT SLK/MPV...BUT THINKING WITH
SFC HIGH PRES/SUBSIDENCE DEPTH OF MOISTURE WL NOT BE ENOUGH TO
PRODUCE CLOUDS...BUT SATL TRENDS WL NEED TO BE MONITORED.
OUTLOOK 18Z WEDNESDAY THROUGH SATURDAY...
SFC HIGH PRES WITH VFR CONDITIONS PREVAIL THRU 00Z FRIDAY...BEFORE
NEXT SYSTEM PRODUCE WIDESPREAD RAIN WITH MVFR CONDITIONS BTWN 06Z
FRIDAY AND 18Z FRIDAY. IN ADDITION...SOME GUSTY SOUTH TO SOUTHEAST
WINDS WL BE POSSIBLE...ESPECIALLY AT RUT...ALONG WITH AREAS OF LLVL
WIND SHEAR AND TURBULENCE THURS NIGHT/FRIDAY MORNING. AREAS OF
SCATTERED SHOWERS WITH MVFR AND BRIEF PERIODS OF IFR AT SLK/MPV WL
BE POSSIBLE FRIDAY AFTN INTO SAT....AS SFC LOW PRES CONTS TO
IMPACT OUR TAF SITES.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS
SHORT TERM...BANACOS
LONG TERM...LAHIFF
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
139 PM EDT TUE OCT 16 2012
.SYNOPSIS...
A COLD FRONT HAS MOVED EAST OF THE REGION. COLDER AIR FILTERING IN
BEHIND THE FRONT COMBINED WITH AN UPPER LEVEL DISTURBANCE WILL BRING
SCATTERED MOUNTAIN SNOW SHOWERS AND A FEW LIGHT RAIN SHOWERS OR
SPRINKLES TO THE VALLEYS THIS MORNING. SKIES WILL CLEAR THIS
AFTERNOON WITH HIGH PRESSURE BRINGING FAIR WEATHER TO THE NORTH
COUNTRY LATER TODAY INTO THURSDAY. A RATHER STRONG LOW PRESSURE
SYSTEM IS EXPECTED TO BRING RAIN FRIDAY INTO SATURDAY.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
AS OF 1232 PM EDT TUESDAY...HAVE UPDATED THE FCST TO DELAY
CLEARING 3-4 HRS BASED ON RAP SOUNDINGS/RH PROFILES AND PREVAILING
OVERCAST ON VIS SATELLITE IMAGERY. IT APPEARS INVERSION NEAR 3 KFT
IS HOLDING FIRM...AND TRAPPING LOW STRATUS LAYER UNTIL CLOSE TO
00Z FOR MOST SECTIONS OF THE CWA. CORRESPONDINGLY...TEMPERATURES
HAVE BEEN LOWERED A FEW DEGREES FOR THIS AFTN. THE REMAINDER OF
THE FCST REMAINS UNCHANGED.
PREVIOUS FORECAST: SCATTERED SPRINKLES/SUMMIT FLURRIES CONTINUE
ACROSS THE NORTH COUNTRY UNDER MAINLY CLOUDY SKIES. A LIGHT
COATING OF SNOW NOTED ON WEATHER CAMS ABOVE 2000` IN THE NRN
ADIRONDACKS AND CENTRAL/NRN GREEN MTNS. SFC LOW NEAR THE MAINE
COAST AND TRAILING DEFORMATION BAND WILL SHIFT AWAY FROM THE NORTH
COUNTRY BY EARLY THIS AFTN. ANTICIPATE ANY REMAINING LIGHT PCPN TO
GRADUALLY END LATE THIS MORNING/EARLY THIS AFTN WITH SKIES
GRADUALLY CLEARING THIS AFTN. HIGH TEMPS GENERALLY IN THE UPR 40S
TO AROUND 50...BUT LOCALLY IN THE MID 40S IN THE NRN ADIRONDACK
REGION AND IN VERMONT IN THE 1-2KFT ELEVATIONAL BAND. MODERATELY
STRONG PRESSURE GRADIENT IN PLACE BEHIND DEEPENING SURFACE LOW
OVER NEW BRUNSWICK. WITH STEEP LOW-LEVEL LAPSE RATES IN
PLACE...LOOKING FOR NW WINDS 10-20 MPH WITH GUSTS 25-30 MPH AT
TIMES. WINDS WILL ABATE TOWARD THIS EVENING.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH THURSDAY/...
AS OF 421 AM EDT TUESDAY...GENERALLY QUIET WEATHER THROUGH THE
PERIOD. SURFACE RIDGE CRESTS OVER THE NORTH COUNTRY TONIGHT WITH
MAINLY CLEAR SKIES EXPECTED. PATCHY FOG POSSIBLE AFTER MIDNIGHT IN
THE FAVORED VERMONT RIVER VALLEYS. LOWS RANGING FROM THE MID AND
UPPER 20S IN THE ADIRONDACKS AND NORTH CENTRAL/NORTHEAST VERMONT TO
THE LOWER AND MID 30S ELSEWHERE. RIDGE AXIS SHIFTS TO THE EAST
DURING THE DAY WEDNESDAY WITH LIGHT SOUTH WINDS DEVELOPING. THIS
WILL ALLOW AIR MASS TO MODERATE SOME ALLOWING FOR HIGH TEMPERATURES
TO REACH THE LOWER 60S IN THE VALLEYS. SKIES WILL BE PARTLY TO MOSTLY
SUNNY WITH SOME MID LEVEL CLOUDS DUE A WEAK DISTURBANCE IN THE FLOW
ALOFT. CONTINUED QUIET WEDNESDAY NIGHT WITH LIGHT SOUTH WINDS IN THE
CHAMPLAIN VALLEY. NOT AS COOL WITH LOWS IN THE LOW TO MID 40S IN
THE CHAMPLAIN AND SAINT LAWRENCE VALLEYS AND 30S ELSEWHERE. HIGH
PRESSURE WILL REMAIN ALONG THE EAST COAST THURSDAY...WHILE LARGE
SCALE LOW PRESSURE SYSTEM APPROACHES FROM THE WESTERN GREAT LAKES
REGION. EXPECT SUN TO GIVE WAY TO INCREASING CLOUDS. IT SHOULD
REMAIN DRY THROUGH THE DAYLIGHT HOURS...WITH JUST A LOW CHANCE OF
SHOWERS LATE IN THE DAY OVER WESTERN ZONES. TEMPS ON THE MILD SIDE
ONCE AGAIN WITH HIGHS IN THE 60S WITH INCREASING SOUTHERLY BREEZES.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 400 AM EDT TUESDAY...A LOT OF UNCERTAINTY EXISTS IN THE
EXTENDED PORTION OF THE FORECAST DUE TO DIFFERING MODEL SOLUTIONS
IN REGARDS TO THE OVERALL SYNOPTIC PATTERN FROM THURSDAY NIGHT
ONWARDS. FORECASTER CONFIDENCE IS LOW.
RELIABLE MEDIUM/LONG TERM MODELS OF THE GFS AND ECMWF SEEM TO
CONTINUE TO BE AT ODDS WITH THE OVERALL HANDLING OF A POTENT LOW
PRESSURE SYSTEM MOVING OUT OF THE GREAT LAKES REGION THURSDAY NIGHT.
OVERALL...THERE IS A GENERAL AGREEMENT IN REGARDS TO THE TRACK FROM
THE GREAT LAKES NORTHEASTWARD THROUGH THE SAINT LAWRENCE VALLEY AND
INTO CENTRAL QUEBEC...BUT THERE ARE HUGE DIFFERENCES IN TIMING. GFS
IS MUCH MORE PROGRESSIVE MOVING THE LOW NORTH OF THE CWA BY SATURDAY
NIGHT...WHILE THE ECMWF LAGS BEHIND BY A GOOD 24 HOURS. HARD TO
PREDICT WHICH IS RIGHT AT THIS POINT...BUT HAVE LEANED TOWARDS THE
ECMWF SOLUTION BASED ON BETTER PERFORMANCE OVER THE LAST WEEK OR SO.
THAT SAID...EXPECTING TO SEE WIDESPREAD RAIN ACROSS THE REGION
DEVELOPING LATE THURSDAY NIGHT...AND CONTINUING THROUGH FRIDAY NIGHT
AS LOW PRESSURE SLOWLY SHIFTS EASTWARD THROUGH THE GREAT LAKES.
COULD BE LOOKING AT SOME DECENT RAINFALL AMOUNTS WITH A STRONG
MOISTURE FEED OFF THE SOUTHEAST COAST...AND THIS WILL NEED TO BE
MONITORED FOR POSSIBLE FLOOD POTENTIAL AS SOIL MOISTURE IS RUNNING
HIGH FROM ABOVE NORMAL PRECIP SO FAR THIS MONTH. STRONG S/SW FLOW
WILL KEEP TEMPS RATHER MILD ACROSS THE REGION WITH LOWS IN THE 50S
AND HIGHS IN THE 60S. S/SW FLOW CONTINUES ON SATURDAY WITH CONTINUED
HIGH CHANCES FOR SHOWERS AS THE LOW SHIFTS NORTHEAST THROUGH THE
SAINT LAWRENCE VALLEY AND TRACKS A COLD FRONT ACROSS THE REGION.
WINDS SHIFT TO THE W/NW POST FRONTAL PASSAGE AND CONTINUED
CLOUDINESS IS LIKELY SATURDAY NIGHT WITH AMPLE WRAP-AROUND MOISTURE
KEEPING SOME SHOWERS AROUND. BY SUNDAY MORNING...HIGH AMPLITUDE
RIDGE BEGINS TO BUILD INTO THE REGION...AND WILL DOMINATE THE NORTH
COUNTRYS WEATHER THROUGH THE REMAINDER OF THE FORECAST PERIOD WITH
DRY AND SEASONAL CONDITIONS EXPECTED.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
THROUGH 18Z WEDNESDAY...AVIATION CHALLENGE IS TIMING OF CLOUDS
DISSIPATING ACRS OUR TAF SITES THIS AFTN/EVENING. CRNT SFC
ANALYSIS SHOWS CYCLONIC UPSLOPE FLW ACRS OUR CWA WITH LOW PRES
LOCATED EAST OF CARIBOU MAINE THIS AFTN. THIS LLVL UPSLOPE
FLW...COMBINED WITH MOISTURE TRAPPED BLW TEMP INVERSION HAS RESULTED
PLENTY OF CLOUDS WITH MVFR CONDITIONS AT MOST SITES. NAM/GFS
VERTICAL SOUNDINGS ARE TOO QUICK AT ERODING THE CLOUDS...GIVEN
MOISTURE/WIND DIRECTION...WL TREND TOWARD THE LATEST RAP
SOUNDINGS. THESE SHOW MVFR BCMG VFR CONDITIONS BY 21Z AT
PBG/BTV/RUT/MSS AND AFT 00Z AT MPV/SLK WITH NW WINDS BECMG
LIGHT/VARIABLE TWD SUNSET. INTERESTING RAP SOUNDINGS CONT TO SHOW
VERY SHALLOW RH PROFILES OVERNIGHT AT SLK/MPV...BUT THINKING WITH
SFC HIGH PRES/SUBSIDENCE DEPTH OF MOISTURE WL NOT BE ENOUGH TO
PRODUCE CLOUDS...BUT SATL TRENDS WL NEED TO BE MONITORED.
OUTLOOK 18Z WEDNESDAY THROUGH SATURDAY...
SFC HIGH PRES WITH VFR CONDITIONS PREVAIL THRU 00Z FRIDAY...BEFORE
NEXT SYSTEM PRODUCE WIDESPREAD RAIN WITH MVFR CONDITIONS BTWN 06Z
FRIDAY AND 18Z FRIDAY. IN ADDITION...SOME GUSTY SOUTH TO SOUTHEAST
WINDS WL BE POSSIBLE...ESPECIALLY AT RUT...ALONG WITH AREAS OF LLVL
WIND SHEAR AND TURBULENCE THURS NIGHT/FRIDAY MORNING. AREAS OF
SCATTERED SHOWERS WITH MVFR AND BRIEF PERIODS OF IFR AT SLK/MPV WL
BE POSSIBLE FRIDAY AFTN INTO SAT....AS SFC LOW PRES CONTS TO
IMPACT OUR TAF SITES.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...RJS
NEAR TERM...BANACOS
SHORT TERM...RJS
LONG TERM...LAHIFF
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1235 PM EDT TUE OCT 16 2012
.SYNOPSIS...
A COLD FRONT HAS MOVED EAST OF THE REGION. COLDER AIR FILTERING IN
BEHIND THE FRONT COMBINED WITH AN UPPER LEVEL DISTURBANCE WILL BRING
SCATTERED MOUNTAIN SNOW SHOWERS AND A FEW LIGHT RAIN SHOWERS OR
SPRINKLES TO THE VALLEYS THIS MORNING. SKIES WILL CLEAR THIS
AFTERNOON WITH HIGH PRESSURE BRINGING FAIR WEATHER TO THE NORTH
COUNTRY LATER TODAY INTO THURSDAY. A RATHER STRONG LOW PRESSURE
SYSTEM IS EXPECTED TO BRING RAIN FRIDAY INTO SATURDAY.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
AS OF 1232 PM EDT TUESDAY...HAVE UPDATED THE FCST TO DELAY
CLEARING 3-4 HRS BASED ON RAP SOUNDINGS/RH PROFILES AND PREVAILING
OVERCAST ON VIS SATELLITE IMAGERY. IT APPEARS INVERSION NEAR 3 KFT
IS HOLDING FIRM...AND TRAPPING LOW STRATUS LAYER UNTIL CLOSE TO
00Z FOR MOST SECTIONS OF THE CWA. CORRESPONDINGLY...TEMPERATURES
HAVE BEEN LOWERED A FEW DEGREES FOR THIS AFTN. THE REMAINDER OF
THE FCST REMAINS UNCHANGED.
PREVIOUS FORECAST: SCATTERED SPRINKLES/SUMMIT FLURRIES CONTINUE
ACROSS THE NORTH COUNTRY UNDER MAINLY CLOUDY SKIES. A LIGHT
COATING OF SNOW NOTED ON WEATHER CAMS ABOVE 2000` IN THE NRN
ADIRONDACKS AND CENTRAL/NRN GREEN MTNS. SFC LOW NEAR THE MAINE
COAST AND TRAILING DEFORMATION BAND WILL SHIFT AWAY FROM THE NORTH
COUNTRY BY EARLY THIS AFTN. ANTICIPATE ANY REMAINING LIGHT PCPN TO
GRADUALLY END LATE THIS MORNING/EARLY THIS AFTN WITH SKIES
GRADUALLY CLEARING THIS AFTN. HIGH TEMPS GENERALLY IN THE UPR 40S
TO AROUND 50...BUT LOCALLY IN THE MID 40S IN THE NRN ADIRONDACK
REGION AND IN VERMONT IN THE 1-2KFT ELEVATIONAL BAND. MODERATELY
STRONG PRESSURE GRADIENT IN PLACE BEHIND DEEPENING SURFACE LOW
OVER NEW BRUNSWICK. WITH STEEP LOW-LEVEL LAPSE RATES IN
PLACE...LOOKING FOR NW WINDS 10-20 MPH WITH GUSTS 25-30 MPH AT
TIMES. WINDS WILL ABATE TOWARD THIS EVENING.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH THURSDAY/...
AS OF 421 AM EDT TUESDAY...GENERALLY QUIET WEATHER THROUGH THE
PERIOD. SURFACE RIDGE CRESTS OVER THE NORTH COUNTRY TONIGHT WITH
MAINLY CLEAR SKIES EXPECTED. PATCHY FOG POSSIBLE AFTER MIDNIGHT IN
THE FAVORED VERMONT RIVER VALLEYS. LOWS RANGING FROM THE MID AND
UPPER 20S IN THE ADIRONDACKS AND NORTH CENTRAL/NORTHEAST VERMONT TO
THE LOWER AND MID 30S ELSEWHERE. RIDGE AXIS SHIFTS TO THE EAST
DURING THE DAY WEDNESDAY WITH LIGHT SOUTH WINDS DEVELOPING. THIS
WILL ALLOW AIR MASS TO MODERATE SOME ALLOWING FOR HIGH TEMPERATURES
TO REACH THE LOWER 60S IN THE VALLEYS. SKIES WILL BE PARTLY TO MOSTLY
SUNNY WITH SOME MID LEVEL CLOUDS DUE A WEAK DISTURBANCE IN THE FLOW
ALOFT. CONTINUED QUIET WEDNESDAY NIGHT WITH LIGHT SOUTH WINDS IN THE
CHAMPLAIN VALLEY. NOT AS COOL WITH LOWS IN THE LOW TO MID 40S IN
THE CHAMPLAIN AND SAINT LAWRENCE VALLEYS AND 30S ELSEWHERE. HIGH
PRESSURE WILL REMAIN ALONG THE EAST COAST THURSDAY...WHILE LARGE
SCALE LOW PRESSURE SYSTEM APPROACHES FROM THE WESTERN GREAT LAKES
REGION. EXPECT SUN TO GIVE WAY TO INCREASING CLOUDS. IT SHOULD
REMAIN DRY THROUGH THE DAYLIGHT HOURS...WITH JUST A LOW CHANCE OF
SHOWERS LATE IN THE DAY OVER WESTERN ZONES. TEMPS ON THE MILD SIDE
ONCE AGAIN WITH HIGHS IN THE 60S WITH INCREASING SOUTHERLY BREEZES.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 400 AM EDT TUESDAY...A LOT OF UNCERTAINTY EXISTS IN THE
EXTENDED PORTION OF THE FORECAST DUE TO DIFFERING MODEL SOLUTIONS
IN REGARDS TO THE OVERALL SYNOPTIC PATTERN FROM THURSDAY NIGHT
ONWARDS. FORECASTER CONFIDENCE IS LOW.
RELIABLE MEDIUM/LONG TERM MODELS OF THE GFS AND ECMWF SEEM TO
CONTINUE TO BE AT ODDS WITH THE OVERALL HANDLING OF A POTENT LOW
PRESSURE SYSTEM MOVING OUT OF THE GREAT LAKES REGION THURSDAY NIGHT.
OVERALL...THERE IS A GENERAL AGREEMENT IN REGARDS TO THE TRACK FROM
THE GREAT LAKES NORTHEASTWARD THROUGH THE SAINT LAWRENCE VALLEY AND
INTO CENTRAL QUEBEC...BUT THERE ARE HUGE DIFFERENCES IN TIMING. GFS
IS MUCH MORE PROGRESSIVE MOVING THE LOW NORTH OF THE CWA BY SATURDAY
NIGHT...WHILE THE ECMWF LAGS BEHIND BY A GOOD 24 HOURS. HARD TO
PREDICT WHICH IS RIGHT AT THIS POINT...BUT HAVE LEANED TOWARDS THE
ECMWF SOLUTION BASED ON BETTER PERFORMANCE OVER THE LAST WEEK OR SO.
THAT SAID...EXPECTING TO SEE WIDESPREAD RAIN ACROSS THE REGION
DEVELOPING LATE THURSDAY NIGHT...AND CONTINUING THROUGH FRIDAY NIGHT
AS LOW PRESSURE SLOWLY SHIFTS EASTWARD THROUGH THE GREAT LAKES.
COULD BE LOOKING AT SOME DECENT RAINFALL AMOUNTS WITH A STRONG
MOISTURE FEED OFF THE SOUTHEAST COAST...AND THIS WILL NEED TO BE
MONITORED FOR POSSIBLE FLOOD POTENTIAL AS SOIL MOISTURE IS RUNNING
HIGH FROM ABOVE NORMAL PRECIP SO FAR THIS MONTH. STRONG S/SW FLOW
WILL KEEP TEMPS RATHER MILD ACROSS THE REGION WITH LOWS IN THE 50S
AND HIGHS IN THE 60S. S/SW FLOW CONTINUES ON SATURDAY WITH CONTINUED
HIGH CHANCES FOR SHOWERS AS THE LOW SHIFTS NORTHEAST THROUGH THE
SAINT LAWRENCE VALLEY AND TRACKS A COLD FRONT ACROSS THE REGION.
WINDS SHIFT TO THE W/NW POST FRONTAL PASSAGE AND CONTINUED
CLOUDINESS IS LIKELY SATURDAY NIGHT WITH AMPLE WRAP-AROUND MOISTURE
KEEPING SOME SHOWERS AROUND. BY SUNDAY MORNING...HIGH AMPLITUDE
RIDGE BEGINS TO BUILD INTO THE REGION...AND WILL DOMINATE THE NORTH
COUNTRYS WEATHER THROUGH THE REMAINDER OF THE FORECAST PERIOD WITH
DRY AND SEASONAL CONDITIONS EXPECTED.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
THROUGH 12Z WEDNESDAY...A MIX OF VFR AND MVFR CONDITIONS WILL
CONTINUE THROUGH AT LEAST 18Z TODAY WITH SOME ISOLATED TO
SCATTERED RAIN/SNOW SHOWERS AROUND AS LOW PRESSURE EXITS NORTHEAST
OFF THE ATLANTIC COAST. IN ADDITION...WNW WINDS WILL CONTINUE TO BE
GUSTY IN THE 20-25 KT RANGE. AFTER 21-00Z...HIGH PRESSURE BUILDS
INTO THE REGION WITH WINDS DIMINISHING AND SKIES TRENDING TO CLEAR
FOR THE OVERNIGHT HOURS.
OUTLOOK 12Z WEDNESDAY THROUGH SATURDAY...
12Z WEDNESDAY THROUGH 00Z FRIDAY...VFR UNDER HIGH PRESSURE.
00Z FRIDAY THROUGH SATURDAY...VFR CONDITIONS TRENDING TO MVFR AND
POSSIBLY IFR IN PERIODS OF RAIN AS LOW PRESSURE MOVES ACROSS THE
REGION.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...RJS
NEAR TERM...BANACOS
SHORT TERM...RJS
LONG TERM...LAHIFF
AVIATION...LAHIFF
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
650 PM EDT TUE OCT 16 2012
.SYNOPSIS...
A WARM FRONT WILL LIFT NORTHEAST ACROSS THE GREAT LAKES TONIGHT AND
WEDNESDAY. A COLD FRONT WILL SWEEP ACROSS THE AREA ON THURSDAY. AN
UPPER LOW WILL DROP SOUTHEAST ACROSS THE MIDWEST ON THURSDAY AND
CROSS THE LOCAL AREA ON FRIDAY INTO SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
INCREASING CLOUDS FOR TONIGHT AND CONTINUED THE 20 POPS. INCREASED
THE POP COVERAGE OVER NORTHWEST OHIO. THE HRRR MODEL SEEMS
OVERDONE AS PER MOST MODELS NOT INDICATING MEASURABLE. WILL
MONITOR THIS FOR THE NEXT UPDATE. AIRMASS SEEMS TO STABLE FOR
THAT. NO CHANGE TO LOWS AT THIS TIME.
SHORT WAVE ZIPPING ACROSS THE UPPER GREAT LAKES LATE THIS
AFTERNOON INTO TONIGHT. THE SHORT WAVE WILL DAMPEN OUT AS THE LONG
WAVE RIDGE BUILDS AND IT IS CHASED BY A MORE SIGNIFICANT WAVE
DIGGING INTO THE HIGH PLAINS. NONETHELESS...THERE IS A DECENT LOW
LEVEL JET AND STRONG WARM ADVECTION...ESSENTIALLY A WARM FRONT.
PRETTY COMMON FOR THESE TYPES OF SYSTEMS TO HAVE ENOUGH UPWARD
MOTION TO GET SOME DROPS TO FALL FROM A MID LEVEL CLOUD DECK.
NOTHING SIGNIFICANT...BUT A PASSING SHOWER COULD REACH THE GROUND
ESPECIALLY ACROSS THE NORTHERN COUNTIES TONIGHT.
LOWS WILL BE WARMER THAN RECENT NIGHTS AS THE SOUTH BREEZE WILL
PERSIST. QUITE A BIT OF THE TEMPERATURE DROP WILL BE THIS EVENING
AND TEMPS MIGHT EVEN RISE A DEGREE OR TWO IN THE DOWNSLOPE AND
LAKESHORE AREAS. LOWS WILL DIP TO THE MID OR UPPER 40S IN MOST
AREAS WITH LOWER 40S ACROSS THE COLD SPOTS OF NW PA.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY NIGHT/...
THE MAJORITY OF MID/HIGH CLOUDS SHOULD MOVE EAST OF THE FORECAST
AREA ON WEDNESDAY. SCATTERED CUMULUS/STRATOCUMULUS MAY DEVELOP OVER
EXTREME NE OH/NW PA...OTHERWISE WE SHOULD SEE A FAIR AMOUNT OF
SUNSHINE AND A BRISK SOUTH BREEZE. BOUNDARY LAYER MODEL
TEMPERATURES SUPPORT LOWER AND MID 70S FOR HIGHS AND SEEING THE
CURRENT TEMPERATURES TO OUR WEST IT SEEMS REASONABLE.
THE MODELS ARE GETTING CLOSE ON THEIR TIMING OF THE COLD/OCCLUDED
FRONT ON THURSDAY...ARRIVING TO NORTHWEST OHIO DURING THE EARLY
MORNING HOURS THURSDAY AND PUSHING ACROSS EXTREME NORTHEAST OHIO AND
NORTHWEST PENNSYLVANIA THURSDAY AFTERNOON. EXPECT A GENERAL
DIMINISHING IN THE SHOWERS AS THE FRONT OUT RUNS THE LOW LEVEL JET
AND ENCOUNTERS THE DOWNSLOPE SSE WIND.
SOME CONCERN FOR WIND ON THURSDAY AS THE 850 MB WIND IS PROGGED
BY MOST MODELS TO ABOUT 60 KNOTS. THE TIMING IS NOT GREAT FOR
REACHING THE MAXIMUM WIND AS THE SHOWERS WITH THE FRONT WILL
STABILIZE THE ATMOSPHERE. THERE COULD BE SOME GOOD GUSTS WITH THE
ONSET OF THE SHOWERS AND THERE WILL BE DECENT GUSTS BEHIND THE
FRONT...MOST LIKELY IN THE 35 TO 40 MPH RANGE. WE WILL HAVE TO
CONTINUE TO MONITOR. THE BOUNDARY LAYER REMAINS RATHER WARM ON
THURSDAY BUT IT IS COOLING OFF ALOFT. OFTEN WE CAN SNEAK HIGH
TEMPERATURES A COUPLE DEGREES WARMER THAN ONE WOULD THINK IN THAT
SITUATION AND WILL FORECAST HIGHS GENERALLY IN THE LOWER/MID 60S.
THE UPPER LOW WILL MOVE INTO THE AREA ON FRIDAY AND EXPECT SHOWERS
TO INCREASE. IF IT IS CLOUDY AND SHOWERY THEN TEMPERATURES
WOULD BE COOL...OR IF THERE WILL BE SOME SUNSHINE AND THE SHOWERS
DEVELOP CONVECTIVELY...IT COULD BE WARMER. WILL BE CONSERVATIVE AND
STAY ON THE COOL SIDE AT THIS TIME...WITH FORECAST HIGHS IN THE
50S.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
UPPER TROUGH OVER THE AREA ON SATURDAY WILL ALLOW FOR CONTINUED
CLOUDS AND LIKELY LAKE EFFECT SHOWERS ACROSS FAR NE OH AND NW PA.
THIS TROUGH WILL QUICKLY MOVE TO THE EAST THROUGH SATURDAY NIGHT
WITH RIDGING DEVELOPING OVER THE AREA FOR SUNDAY. COOLER TEMPS
EXPECTED ON SATURDAY WITH THE TROUGH...BUT QUICKLY REBOUNDING ON
SUNDAY WITH READINGS CLIMBING BACK WELL INTO THE 60S FOR THE WEST
AND NEAR 60 FOR THE EAST. HIGH PRESSURE SLIDES OFF TO THE EAST
MONDAY WITH DEVELOPING SOUTH FLOW AND WARM AIR ADVECTION ACROSS THE
AREA.
MODELS CONTINUING TO MAKE CHANGES FOR THE NEXT FRONTAL PASSAGE AT
THE VERY END OF THE PERIOD...WITH LATEST 12Z ECMWF CLOSER TO THE
GFS. FOR NOW ADDED IN POPS MONDAY NIGHT ACROSS THE NORTHERN HALF OF
THE AREA WITH MILD OVERNIGHT TEMPS AHEAD OF THE FRONT.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
LOWER CLOUDS DISSIPATING ACROSS EASTERN SITES FROM ERI-YNG EARLY
THIS AFTERNOON. VFR CONDITIONS EXPECTED THROUGH TONIGHT AS A WARM
FRONT APPROACHING THE AREA. MID CLOUDS ARE EXPECTED TO BUILD
ACROSS WESTERN SITES AFTER MIDNIGHT AND BUILD EASTWARD OVERNIGHT.
THERE IS THE CHANCE FOR SOME SPRINKLES BETWEEN 07-12Z ACROSS
WESTERN SITES TO NEAR CLE...BUT CONFIDENCE LOW AT THIS POINT AND
WILL NOT INCLUDE IN TAF FORECASTS. WARM FRONT WILL PUSH NORTH OF
LAKE ERIE WED MORNING ALLOWING FOR CLEARING SKIES...BUT SOUTH
WINDS WILL INCREASE QUICKLY IN THE MORNING AND BECOME GUSTY BY
MIDDAY.
.OUTLOOK...NON VFR DEVELOPING THURSDAY/THURSDAY NIGHT IN SHOWERS
ASSOCIATED WITH THE NEXT COLD FRONT. NON VFR LINGERING AT TIMES ON
FRIDAY AND SATURDAY AS A TROUGH OF LOW PRESSURE REMAINS OVER THE
GREAT LAKES.
&&
.MARINE...
HIGH PRESSURE OVER THE REGION WILL BUILD TO THE EAST COAST ON
WEDNESDAY. THIS WILL ALLOW SOUTHERLY WINDS TO INCREASE AHEAD OF THE
NEXT LOW PRESSURE SYSTEM. WINDS WILL INCREASE TO 20 TO 25 KNOTS FOR
A PERIOD OF TIME...VEERING TO SOUTHWEST BEHIND THE PASSAGE OF A COLD
FRONT. A SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED FOR A PERIOD OF
TIME ON THURSDAY.
THIS BROAD AREA OF LOW PRESSURE WILL SLOWLY DRIFT EAST ACROSS THE
REGION THROUGH THE END OF THE WEEK. HIGH PRESSURE WILL BUILD OVER
THE OHIO VALLEY ON SATURDAY WITH DECREASING WINDS AND WAVES.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KOSARIK
NEAR TERM...KIELTYKA/KOSARIK
SHORT TERM...KOSARIK
LONG TERM...ABE
AVIATION...ABE
MARINE...KEC
AREA FORECAST DISCUSSION
NWS SPOKANE WA
ISSUED BY NATIONAL WEATHER SERVICE PENDLETON OR
1035 AM PDT TUE OCT 16 2012
.SYNOPSIS...WINDY CONDITIONS WITH SCATTERED RAIN AND HIGH MOUNTAIN
SNOW SHOWERS WILL AFFECT THE REGION TODAY. WIND GUSTS OF 35 TO 50 MPH
WILL BE LIKELY THROUGH THIS EVENING OVER PORTIONS OF THE INLAND
NORTHWEST. A DRIER, MORE STABLE PATTERN IS EXPECTED FOR WEDNESDAY
AND THURSDAY, BEFORE MORE PRECIPITATION CHANCES ENTER LATE IN THE
WEEK WITH COOLER TEMPERATURES.
&&
.UPDATE...ONLY MINOR UPDATES WERE MADE TO THE CURRENT FORECAST.
ISOLATED THUNDERSTORMS HAVE BEEN OBSERVED OVER THE IDAHO
PANHANDLE, SO I EXTENDED THE THE THREAT OF THUNDERSTORMS UNTIL
LATE MORNING. A FEW UPDATES WERE MADE TO INCREASE TEMPERATURES IN
THE PALOUSE AND LEWISTON AREAS. WINDS ARE MEETING ADVISORY
CRITERIA (I.E. 25-35 MPH GUSTING TO 45-50 MPH) ACROSS THE COLUMBIA
BASIN AND THE WASHINGTON PALOUSE, AND I INCLUDED THE CAMAS PRAIRIE
AREA IN THE ADVISORY.
&&
.AVIATION...
18Z TAFS: MAIN IMPACTS TODAY WILL BE WINDS. GUSTY WESTERLY WINDS
WILL CONTINUE THROUGH THE AFTERNOON BEFORE DIMINISHING THIS EVENING.
SUSTAINED WINDS WILL BE 15-30KT WITH GUSTS 30-40KT. DOWNSLOPE FLOW
OFF THE CASCADES WILL PROVIDE MAINLY CLEAR SKIES FOR THE COLUMBIA
BASIN TAF SITES WITH SCT-BKN 040-060 ELSEWHERE. WINDS WILL DECREASE
TO 5-15KT LATER THIS EVENING INTO THE OVERNIGHT PERIOD. 94
&&
.PREV DISCUSSION... /ISSUED 436 AM PDT TUE OCT 16 2012/
..VERY WINDY CONDITIONS TODAY...
TODAY AND TONIGHT...THE COLD FRONT CONTINUES TO MOVE SOUTHEAST
ACROSS THE FORECAST AREA THIS MORNING WITH THE BACK EDGE JUST SOUTH
OF THE I-90 CORRIDOR AS OF 08Z. THE MAIN AREA OF STEADY RAIN IS
CONFINED TO SHOSHONE COUNTY BUT WIDELY SCATTERED SHOWERS ARE
POPPING UP ALL ACROSS THE AREA IN THE UNSTABLE POST FRONTAL AIR
MASS. A FEW LIGHTNING STRIKES HAVE BEEN RECORDED ACROSS THE EXTREME
NORTHERN CASCADES AND ACROSS SOUTHERN BC. THE COLD POOL ALOFT WILL
KEEP THINGS UNSETTLED ENOUGH FOR A SLIGHT CHANCE OF THUNDERSTORMS
THROUGH ABOUT 15Z BEFORE THE BEST FORCING MOVES EAST. GUSTY WINDS
ARE STARTING TO INCREASE AS THE SURFACE PRESSURE GRADIENT
STRENGTHENS BETWEEN THE DEEPENING LOW OVER SOUTHERN ALBERTA AND HIGH
PRESSURE OFF THE COAST. THE GRADIENT IS EXPECTED TO MAX OUT LATE
THIS MORNING TO EARLY AFTERNOON. THE BENCHMARK THAT WILL SUPPORT A
HIGH WIND WARNING IS AT LEAST A 24MB DIFFERENCE BETWEEN LETHBRIDGE,
ALBERTA (CYQL) AND YAKIMA (KYKM) ALONG WITH SYNOPTIC SUPPORT FROM A
JET STREAK OVERHEAD. WE WILL BE JUST SHY OF THE GRADIENT AND THE JET
WILL SAG TO THE SOUTH THIS AFTERNOON. THIS LIKELY MEANS THAT WE WILL
BE SEEING A HIGH END WIND ADVISORY. THERE COULD POSSIBLY BE ONE OR
TWO OF THE WINDIER SITES BREAKING INTO HIGH WIND CRITERIA BUT
WIDESPREAD DAMAGING WINDS ARE NOT EXPECTED WITH THIS SYSTEM. IT WILL
ALSO BE A FAST MOVER, WITH THE LOW SLIDING INTO THE CANADIAN
PRAIRIES BY 00Z, WEAKENING THE GRADIENT. NO CHANGES MADE TO THE
ONGOING WIND ADVISORY AT THIS TIME.
ANOTHER CONCERN WILL BE SNOW LEVELS FOR THE EAST SLOPES OF THE
CASCADES. MODELS ARE BRINGING THE 850MB 0C LINE ALONG THE CREST WITH
THE NAM12 DOWN TO -1C THIS MORNING. RADAR MOSAIC IS SHOWING SOME
EVIDENCE OF A CONVERGENT ZONE. THE HRRR MODEL AGREES, BUT SHOWS THE
PLUME DRIFTING SOUTH ALONG THE CREST INTO SLIGHTLY WARMER AIR.
DEPENDING ON THE LOCATION AND PERSISTENCE OF THIS FEATURE, SOME OF
THE HIGHER VALLEYS COULD SEE SOME LIGHT SNOWFALL ACCUMULATION. AFTER
A RELATIVELY MILD MORNING, DUE TO STRONG MIXING BY GUSTY WINDS,
TEMPERATURES WILL NOT WARM VERY MUCH TODAY AS COLD AIR ADVECTION
TAKES OVER. EXPECT CHILLY TEMPERATURES TONIGHT WITH MOST OF THE
NORTHERN VALLEYS DIPPING BELOW THE FREEZING MARK. FOR OTHER VALLEY
LOCATIONS, MID 30S WILL BE COMMON. /KELCH
WEDNESDAY THROUGH THURSDAY...LATEST MODELS ARE IN GOOD AGREEMENT
FOR THIS PERIOD. A QUITE BREAK WILL GRACE THE REGION AS A WEAK
BUT PERCEPTIBLE SHORT WAVE RIDGE BUILDS OVER THE FORECAST AREA IN
THE WAKE OF TUESDAY`S UNPLEASANTNESS. RESIDUAL BREEZY WINDS AND
LINGERING SHOWERS OVER THE IDAHO PANHANDLE WILL DECREASE WEDNESDAY
MORNING AS SURFACE HIGH PRESSURE SETTLES OVER THE REGION. WEDNESDAY`S
HIGHS WILL PEAK RIGHT AROUND SEASONAL NORMAL WITH GENERALLY PARTLY
CLOUDY TO MOSTLY SUNNY SKIES. THE QUIET BREAK WILL CONTINUE ON
THURSDAY ALTHOUGH THE RIDGE AXIS WILL PASS TO THE EAST OF THE
REGION AND OPEN THE WAY FOR INCREASING HIGH CLOUDS AS THE NEXT
WEATHER SYSTEM APPROACHES. THE RETREAT OF THE RIDGE AXIS WILL
ALLOW SOME WARM ADVECTION TO BEGIN ON THURSDAY IN THE PRE-FRONTAL
SOUTHWEST FLOW REGIME...PROMOTING HIGH TEMPERATURES ONCE AGAIN
SLIGHTLY ABOVE NORMAL...BUT WITH SUNSHINE FILTERED THROUGH
THICKENING CLOUDS ESPECIALLY ACROSS THE NORTHERN ZONES.
THURSDAY NIGHT AND FRIDAY...THE GFS AND ECMWF MODELS ADVERTISE A
RIDGE BREAKDOWN AND SUBSEQUENT COLD FRONT PASSAGE EITHER THURSDAY
NIGHT (GFS) OR FRIDAY (EC). BOTH MODELS HAVE STUCK TO THEIR
RESPECTIVE TIMING DIFFERENCES OVER THE LAST FEW RUNS. THE DRIVING
FORCE OF A 120-140KT JET OVER THE GULF OF ALASKA ASSOCIATED WITH
THIS WAVE SUGGEST THE FASTER GFS MAY BE THE BEST SOLUTION TO WORK
WITH. FORECAST WILL BE BASED UPON THIS REASONING...WHICH YIELDS
HIGH POPS OVER MUCH OF THE FORECAST AREA THURSDAY NIGHT AND INTO
FRIDAY MORNING AS A STRONG FETCH OF PRECIPITABLE WATER ENHANCES
ALONG THE COLD FRONT WITH GOOD AND WELL DEFINED JET DIVERGENCE AND
DIFFERENTIAL PVA. HIGH TEMPERATURES FRIDAY ARE LOW
CONFIDENCE...WITH THE CURRENT FORECAST REFLECTING AN ASSUMPTION
OF A MORNING PRECIPITATION THREAT FOLLOWED BY GOOD AFTERNOON
ADIABATIC MIXING PROMOTING HIGH TEMPERATURES ABOVE AVERAGE...BUT
IF THE EC IS CORRECT THEN HIGHS MAY TOP OUT CLOSER TO AVERAGE. IN
ANY EVENT...AFTER THE RELATIVELY BENIGN CONDITIONS OF WEDNESDAY
AND THURSDAY...THERE IS HIGH CONFIDENCE THAT FRIDAY WILL BRING A
CHANGE TO THIS PATTERN.
FRIDAY NIGHT THROUGH MONDAY...THINGS GET RATHER MESSY AND
UNCERTAIN DURING THIS PERIOD WITH RESPECT TO TIMING MULTIPLE MINOR
WAVES AND FRONTS IN A MUCH MORE PROGRESSIVE...COOLER AND WET
PATTERN. WHERE CERTAINTY IS HIGHER IS THE OVERALL PATTERN
REFLECTED BY ALL THE LATEST MODELS FEATURING A COOL ZONAL OR
MODERATELY COLD TROFFY FLOW REGIME WITH THE STORM TRACK TO THE
SOUTH OF THE FORECAST AREA. THIS ARGUES FOR A BROAD BRUSH APPROACH
FEATURING A CHANCE OF VALLEY RAIN AND MOUNTAIN SNOW EACH DAY
THROUGH THE WEEKEND AND EARLY NEXT WEEK...WITH THE ADDED
POSSIBILITY OF SOME OVERNIGHT NON-ACCUMULATING SNOW FLAKES DOWN
TO THE VALLEY AND BASIN FLOORS IF ANY PARTICULAR DISTURBANCE RIDES
THROUGH DURING THE OVERNIGHT OR EARLY MORNING HOURS. THE DEEP
BASIN IN THE LEE OF THE CASCADES WILL PROBABLY MISS OUT ON ANY
SIGNIFICANT PRECIPITATION GIVEN THE RAIN SHADOW PROMOTING MEAN
WESTERLY FLOW. DURING THIS PERIOD THE MOUNTAINS ABOVE 4000 TO 5000 FEET
ARE LIKELY TO RECEIVE THEIR FIRST SIGNIFICANT SNOW
ACCUMULATIONS...SLOWLY BUILDING UP TO THREE TO SEVEN INCHES
THROUGH THE WEEKEND. THUS...CONFIDENCE IS HIGH FOR A RAW...BREEZY
AND OCCASIONALLY WET REGIME DURING THIS PERIOD...ALTHOUGH
CONFIDENCE IS LOW REGARDING TIMING OF ANY OF THE EXPECTED
TRANSIENT FOCUSING MECHANISMS AND FRONTS. /FUGAZZI
&&
.PRELIMINARY POINT TEMPS/POPS...
SPOKANE 58 37 54 37 60 43 / 10 10 0 0 10 60
COEUR D`ALENE 60 34 53 33 60 40 / 20 10 0 0 10 60
PULLMAN 57 31 53 36 62 42 / 30 10 0 0 10 60
LEWISTON 63 39 58 40 68 47 / 20 10 0 0 10 50
COLVILLE 60 29 57 34 60 36 / 20 10 10 0 10 60
SANDPOINT 53 33 52 32 57 39 / 40 10 10 0 10 60
KELLOGG 50 35 48 32 56 39 / 80 20 10 0 10 70
MOSES LAKE 62 34 60 37 64 42 / 10 0 0 0 10 20
WENATCHEE 58 40 57 39 65 45 / 10 0 0 0 10 30
OMAK 61 33 59 37 62 38 / 0 0 0 10 10 60
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...WIND ADVISORY UNTIL 8 PM PDT THIS EVENING FOR COEUR D`ALENE AREA-
IDAHO PALOUSE-LEWIS AND SOUTHERN NEZ PERCE COUNTIES-
LEWISTON AREA.
WA...WIND ADVISORY UNTIL 8 PM PDT THIS EVENING FOR LOWER GARFIELD AND
ASOTIN COUNTIES-MOSES LAKE AREA-SPOKANE AREA-UPPER COLUMBIA
BASIN-WASHINGTON PALOUSE-WATERVILLE PLATEAU-WENATCHEE AREA.
&&
$$