Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 10/13/14
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
915 PM CDT SUN OCT 12 2014
.UPDATE...
MADE A FEW MINOR CHANGES TO THE CURRENT FORECAST BUT MAINLY FOR
THIS EVENING. HOWEVER...THE POTENTIAL SEVERE EVENTS LOOKS TO BE ON
TRACK. AN AREA OF SHOWERS AND THUNDERSTORMS HAVE DEVELOPED OVER
THE SOUTH AND SOUTHEAST PARTS OF THE STATE AND ARE ASSOCIATED WITH
THE DEVELOPING LOW LEVEL JET. HAVE ADJUSTED POPS UPWARDS HERE TO
ACCOUNT FOR THIS ACTIVITY.
WE ARE STILL LOOKING FOR A LINE OF STRONG TO SEVERE THUNDERSTORMS
TO DEVELOP IN THE SOUTHERN PLAINS TONIGHT IN ASSOCIATION WITH A
VIGOROUS UPPER TROUGH MOVING THROUGH THE NATIONS MIDSECTION.
LATEST MOISTURE CHANNEL IMAGERY SHOWS THIS LINE MAY BE STARTING TO
ORGANIZE OVER WEST CENTRAL TEXAS. WHILE THERE ARE SOME MODEL
DIFFERENCES IN THE EXACT TIMING...WITH THE HRRR MODEL THE QUICKEST
OF ALL...STILL FEEL THE ORIGINAL THINKING WITH THE LINE REACHING
THE WEST BY MORNING AND RACING EAST DURING THE DAY WILL HOLD. WILL
CONTINUE ALL VALID WIND AND FLOODING HIGHLIGHTS.
OTHER CHANGES TONIGHT INCLUDED TWEAKING OVERNIGHT LOWS A TOUCH.
OVERALL TEMPERATURES ARE EXPECTED TO REMAIN NEARLY STEADY THROUGH
THE NIGHT. ALL UPDATES OUT.
&&
.PREV DISCUSSION... /ISSUED 712 PM CDT SUN OCT 12 2014/
AVIATION...
TAF PERIOD STARTS WITH CLEAR SKIES ACROSS THE NORTHERN ARKANSAS AND
SHOWERS AND A FEW ISOLATED THUNDERSTORMS ACROSS PORTIONS OF
CENTRAL AND SOUTHERN ARKANSAS. WIND SHEAR IS A CONCERN THIS
EVENING AND OVERNIGHT AS LLJ SETS UP ACROSS THE AREA. DID HAVE
SOME MENTIONS OF SHOWERS IN DURING THE OVERNIGHT HOURS...HOWEVER
IF SOME OF THE HIGHER RES MODELS PAN OUT...THERE COULD BE THE
POSSIBILITY OF SOME THUNDER BEGINNING AROUND 6Z.
WINDS WILL BE QUITE WINDY ON MONDAY WITH GUSTS UP TO 25 KTS
EXPECTED. HOWEVER...THE MAIN STORY ON MONDAY ARE THE SHOWERS AND
THUNDERSTORMS THAT ARE EXPECTED TO FORM INTO A LINE AND MOVE
EASTWARD THROUGH THE STATE. THIS LINE IS EXPECTED TO REACH
KHRO AS EARLY AS 12Z...KLIT BY 17Z...AND KPBF AND KLLQ BY 18Z. THE
MAIN THREAT FROM THESE STORMS WILL LIKELY BE DAMAGING WINDS AND
TORRENTIAL RAIN. VISIBILITIES WILL BE SEVERELY REDUCED DURING THE
PASSAGE OF THE LINE...BUT AT THIS TIME IS TOO FAR OUT TO PINPOINT.
PREV DISCUSSION... /ISSUED 310 PM CDT SUN OCT 12 2014/
AVIATION...
LOW CLOUDS/MVFR CONDITIONS WILL BE COMMON THIS AFTERNOON
ACROSS MUCH OF ARKANSAS. HEADING INTO THE OVERNIGHT HOURS...
THERE MAY BE A BRIEF PERIOD THIS EVENING WHEN VFR CONDITIONS
RETURN TO SOME AREAS...AND LOW CLOUDS BREAK UP. OTHERWISE...
LOOK FOR WIDESPREAD LOW CLOUDS AND SCATTERED SHOWERS AND A
FEW THUNDERSTORMS.
A STORM SYSTEM WILL DEVELOP IN THE SOUTHERN PLAINS OVERNIGHT...
WITH WIND SHEAR DEVELOPING ACROSS NORTHERN/WESTERN ARKANSAS.
SOUTH/SOUTHWEST WINDS WILL INCREASE TO 40 TO 50 KNOTS.
ON COLUMBUS DAY...LOW CLOUDS WILL LIFT IN THE MORNING ACROSS THE
SOUTHEAST HALF OF THE STATE...WITH VFR CONDITIONS EXPECTED. IN THE
WEST...A LINE OF SHOWERS AND THUNDERSTORMS WILL MOVE INTO THE AREA.
THE LINE WILL REACH CENTRAL SECTIONS BY THE LATE MORNING HOURS.
SURROUNDING THE LINE...MVFR TO IFR CEILINGS WILL BE NOTED...AND
WINDS WILL BE GUSTY. VIBILITIES WILL BE LOWERED BY VERY HEAVY
RAIN. (46)
SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT
NOT MUCH HAS CHANGED WITH THE GOING FORECAST. THE BIG TOPIC OF
DISCUSSION IN THE SHORT TERM IS THE PENDING ARRIVAL OF A STRONG
FRONT AND ASSOCIATED LINEAR CONVECTIVE COMPLEX DURING THE DAY
MONDAY. THE FRONTAL BOUNDARY SHOULD BE MOVING INTO WESTERN
ARKANSAS AROUND OR SHORTLY BEFORE DAYBREAK...AND WILL QUICKLY
SHIFT EAST THROUGH THE DAY. EXPECT THE FRONT TO MOVE THROUGH
CENTRAL ARKANSAS BY MIDDAY...AND EAST OF THE FORECAST AREA BY
EARLY EVENING. INSTABILITY WILL BE LIMITED WITH ALONG/AHEAD OF THE
FRONT BUT WILL BE SUFFICIENT TO SUPPORT STRONG TO SEVERE STORMS
WHEN PAIRED WITH THE IMPRESSIVE WIND SHEAR THAT WILL BE ON TAP.
CURRENT THOUGHTS ARE THAT SEVERE CHANCES IN WESTERN ARKANSAS WILL
BE ON THE LOWER SIDE DUE TO THE FRONT ARRIVING DURING THE MORNING
HOURS WHEN STATIC STABILITY WILL BE HIGHER AND CLOUD COVER
THICKER. AS THE FRONT PROGRESSES INTO EASTERN ARKANSAS BETTER
INSTABILITY WILL BE AVAILABLE AND A DAMAGING WIND THREAT WILL
EMERGE. THE TORNADO THREAT WILL NOT BE EXTREMELY HIGH...BUT WITH
SUCH WIND SHEAR IN PLACE ANY BREAKS IN THE LINE COULD PRODUCE
BRIEF TORNADOES. IN ADDITION TO THE STRONG STORMS...FLASH
FLOODING WILL BE A PROBLEM AS WELL. WHILE PRECIPITATION TOTALS ARE
NOT EXPECTED TO BE OVERLY IMPRESSIVE...GENERALLY SPEAKING A QUICK
1-2 INCHES WITH LOCALLY HIGHER AMOUNTS...THESE QUICK DOWNPOURS
WILL AFFECT AREAS WITH ALREADY SATURATED SOILS. HOISTED A FLASH
FLOOD WATCH FOR THE NORTHWESTERN HALF OF THE FORECAST
AREA...MAINLY DUE TO EXPECTED TERRAIN EFFECTS WITH SUCH HIGH RAIN
RATES.
OTHERWISE THE ONLY CONCERNS IN THE SHORT TERM ARE ADVISORY LEVEL
WINDS AHEAD OF...AND BEHIND THE FRONT TOMORROW...AND HOW LONG
SHOWER ACTIVITY WILL LINGER AROUND THE NORTHERN HALF OF THE STATE
AS THE UPPER LOW TRAVERSES THE AREA LATE MONDAY THROUGH TUESDAY. HAVE
LAKE WIND...AND WIND ADVISORIES IN PLACE TO HANDLE THE
WINDS...WITH GUSTS RANGING FROM 30-40 MPH TOMORROW IN THE DELTA
REGION AND 25-30 MPH IN THE WESTERN HALF OF THE STATE. BEHIND THE
FRONT SHOWERS WILL LINGER IN THE NORTHERN HALF OF THE STATE
THROUGH TUESDAY AS THE UPPER LOW MOVES OVERHEAD. SOME ADDITIONAL
STRONG STORMS WITH THE POTENTIAL FOR SOME LARGE HAIL COULD BE SEEN
MONDAY AFTERNOON AND EVENING...BUT OTHERWISE JUST SCATTERED
SHOWERS WILL BE SEEN.
LONG TERM...THURSDAY THROUGH SATURDAY NIGHT
IT LOOKS LIKE A TRANQUIL EXTENDED PERIOD...WITH A RIDGE OF HIGH
PRESSURE ALONG THE GULF COAST...AND CLOSE TO A ZONAL FLOW AROUND
HERE. THERE MAY BE A FRONTAL PASSAGE ON FRIDAY...BUT MOISTURE WILL
BE LIMITED AND IT WILL NOT BE NOTICED MUCH. ANY STORM SYSTEMS WILL
GO WELL TO THE NORTH. TEMPERATURES THROUGH THE PERIOD WILL BE CLOSE
TO NORMAL TO PERHAPS A LITTLE ABOVE NORMAL.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 61 73 54 60 / 60 100 50 20
CAMDEN AR 67 78 54 69 / 50 100 20 10
HARRISON AR 59 73 50 59 / 80 100 40 30
HOT SPRINGS AR 65 75 54 66 / 60 100 20 10
LITTLE ROCK AR 64 78 55 66 / 60 100 30 20
MONTICELLO AR 68 77 54 68 / 70 100 40 10
MOUNT IDA AR 64 72 52 66 / 70 100 30 10
MOUNTAIN HOME AR 58 73 52 59 / 70 100 40 30
NEWPORT AR 62 74 55 61 / 50 100 50 20
PINE BLUFF AR 66 79 54 67 / 60 100 40 10
RUSSELLVILLE AR 62 71 54 64 / 70 100 40 20
SEARCY AR 60 71 54 64 / 50 100 40 20
STUTTGART AR 65 77 54 65 / 50 100 40 20
&&
.LZK WATCHES/WARNINGS/ADVISORIES...
LAKE WIND ADVISORY FROM 7 AM TO 7 PM CDT MONDAY FOR BAXTER-BOONE-
CLARK-CLEBURNE-CONWAY-FAULKNER-FULTON-GARLAND-HOT SPRING-
INDEPENDENCE-IZARD-JOHNSON-LOGAN-MARION-MONTGOMERY-NEWTON-PERRY-
PIKE-POLK-POPE-PULASKI-SALINE-SCOTT-SEARCY-SHARP-STONE-VAN BUREN-
YELL.
FLASH FLOOD WATCH FROM 5 AM CDT MONDAY THROUGH MONDAY AFTERNOON
FOR BAXTER-BOONE-CLEBURNE-CONWAY-FAULKNER-FULTON-GARLAND-IZARD-
JOHNSON-LOGAN-MARION-MONTGOMERY-NEWTON-PERRY-PIKE-POLK-POPE-
SCOTT-SEARCY-STONE-VAN BUREN-YELL.
WIND ADVISORY FROM 10 AM TO 7 PM CDT MONDAY FOR ARKANSAS-BRADLEY-
CALHOUN-CLEVELAND-DALLAS-DESHA-DREW-GRANT-JACKSON-JEFFERSON-
LINCOLN-LONOKE-MONROE-OUACHITA-PRAIRIE-WHITE-WOODRUFF.
&&
$$
56
AREA FORECAST DISCUSSION...UPDATED
NWS LITTLE ROCK AR
1256 AM CDT SAT OCT 11 2014
.AVIATION...
WIDESPREAD TSRA ACROSS THE SOUTH...WITH THE NEXT ROUND MOVING
TOWARDS CENTRAL AND NORTHERN ARKANSAS. MVFR CONDITIONS ACROSS MUCH
OF THE AREA WITH SOME IFR/LIFR CONDITIONS IN AREAS OF RAINFALL.
THERE WILL BE A BREAK IN PRECIP LATER THIS AFTERNOON...BUT
IFR/LIFR CONDITIONS WILL MOVE IN AFTER 12/00Z.
&&
.PREV DISCUSSION... /ISSUED 1003 PM CDT FRI OCT 10 2014/
UPDATE...
WIDESPREAD LIGHT TO OCCASIONALLY MODERATE RAIN CONTINUES OVER A
GOOD PORTION OF THE FORECAST AREA AT THIS TIME AS A FRONTAL SYSTEM
CONTINUES TO SINK SOUTH. AN OCCASIONAL THUNDERSTORM OR TWO ALONG
THE LEADING EDGE OF THE FRONT HAVE HAD A HISTORY OF BECOMING
BRIEFLY SEVERE. A STRAY STRONG TO SEVERE STORM CAN NOT BE RULED
OUT THIS EVENING. WHATS LEFT OF THE SEVERE THUNDERSTORM WATCH
EXPIRED AT 10 PM.
PRECIPITATION HAS BEEN VERY LIGHT ACROSS PARTS OF THE NORTH AND
PULLING THE WATCH WAS CONSIDERED BRIEFLY. HOWEVER NEW NAM MODEL
AND LATEST HRRR MODEL DOES GENERATE SOME DECENT QPF TONIGHT. WITH
ACTIVITY STILL ONGOING OVER EASTERN OKLAHOMA...I DECIDED TO ERR ON
THE SIDE OF CAUTION AND MAINTAIN THE WATCH AND LET IT EXPIRE AT
12Z SATURDAY MORNING. THE HEAVIER RAIN AXIS WILL CONTINUE ACROSS
CENTRAL AND EVENTUALLY SOUTHERN ARKANSAS AND WILL LET THE
OTHER FLASH FLOOD WATCH RIDE AS WELL.
CHANGES THIS EVENING ARE TO TWEAK THE CURRENT FORECAST/GRIDS BASED
ON CURRENT TRENDS AND A PEEK AT THE INCOMING MODELS. ALL UPDATES
OUT.
PREV DISCUSSION... /ISSUED 343 PM CDT FRI OCT 10 2014/
SHORT TERM...TONIGHT THROUGH MONDAY NIGHT
HEAVY RAIN OCCURRED TOWARD THE MISSOURI BORDER TODAY. MORE THAN
TWO INCHES OF PRECIPITATION FELL IN PORTIONS OF THE OZARKS. RAIN
WILL BUILD SOUTH WITH A SLOW MOVING FRONT.
AS THE FRONT HEADS INTO THE CENTRAL THIRD OF ARKANSAS THIS
EVENING...THERE COULD BE A FEW SEVERE STORMS. ISOLATED SEVERE
WEATHER WAS ONGOING IN EASTERN OKLAHOMA...WITH A SEVERE
THUNDERSTORM WATCH POSTED THROUGH THIS EVENING IN THE OUACHITA
MOUNTAINS OF THE WEST.
RAIN WILL BE LIKELY IN CENTRAL/SOUTHERN SECTIONS OF THE STATE
TONIGHT AND SATURDAY. AMOUNTS COULD BE HEAVY...WITH GENERAL HALF
INCH TO INCH AND A HALF TOTALS IN THE FORECAST. LOCAL TOTALS COULD
EXCEED TWO INCHES.
HAVE A FLASH FLOOD WATCH LINGERING IN THE FAR NORTH TONIGHT...WITH
A FLASH FLOOD WATCH IN CENTRAL/SOUTHERN SECTIONS THROUGH SATURDAY.
AT THIS POINT...WIDESPREAD HIGH WATER PROBLEMS ARE UNLIKELY...WITH
MOST OF THE WATER GOING INTO THE SOIL FOLLOWING A DRY SEPTEMBER.
RAIN WILL TAPER OFF SATURDAY NIGHT/SUNDAY...WITH SCATTERED SHOWERS
IN THE FORECAST. A STRONG STORM SYSTEM WILL DRAG A NEW COLD FRONT
INTO THE REGION SUNDAY NIGHT/MONDAY...WITH SHOWERS AND THUNDERSTORMS
PICKING UP AGAIN.
THERE WILL BE TORRENTIAL DOWNPOURS WITH THE NEW SYSTEM...AND A QUICK
ONE TO TWO INCHES OF RAIN. FLASH FLOODING MAY BECOME MORE OF AN
ISSUE. GIVEN THE DYNAMICS OF THE SYSTEM...THERE IS A POTENTIAL FOR
SEVERE STORMS. HOWEVER...MUCH OF THE PRECIPITATION WILL OCCUR
DURING THE DAYLIGHT HOURS WHICH WILL LIMIT HEATING/INSTABILITY.
AREAS TOWARD THE MISSISSIPPI RIVER ARE FAVORED IF SEVERE STORMS
DEVELOP...OR WHERE THE MOST HEATING TAKES PLACE BEFORE THE FRONT
ARRIVES.
LONG TERM...TUESDAY THROUGH FRIDAY
UPPER LOW PRESSURE WILL BE CENTERED OVER LAKE MICHIGAN TO BEGIN THE
PERIOD AND THE TRAILING TROUGH WILL BE MOVING EAST OF ARKANSAS.
NORTHWEST FLOW WILL INCREASE OVER ARKANSAS TUESDAY AS AN UPPER RIDGE
BUILDS OVER THE ROCKIES TUESDAY AND WEDNESDAY. THE UPPER RIDGE WILL
MOVE TO NEAR THE MISSISSIPPI RIVER BY WEDNESDAY NIGHT. SOUTHWEST
FLOW WILL RETURN TO THE STATE THURSDAY AND FRIDAY.
THE UPPER LEVEL SYSTEM WILL BE EXITING ARKANSAS TUESDAY
MORNING...AND THERE WILL BE A SLIGHT CHANCE OF SHOWERS IN EASTERN
ARKANSAS THROUGH MID MORNING. HIGH PRESSURE WILL BE OVER THE AREA
THROUGH MUCH OF THE PERIOD WITH DRY WEATHER AND NEAR NORMAL
TEMPERATURES EXPECTED THROUGH THURSDAY. A COLD FRONT WILL MOVE
THROUGH THE AREA FRIDAY BUT NO PRECIPITATION IS EXPECTED AT THIS
TIME.
&&
.LZK WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH THIS EVENING FOR ARKANSAS-CLARK-
CLEBURNE-CONWAY-FAULKNER-GARLAND-GRANT-HOT SPRING-INDEPENDENCE-
JACKSON-JEFFERSON-JOHNSON-LOGAN-LONOKE-MONROE-MONTGOMERY-PERRY-
PIKE-POLK-POPE-PRAIRIE-PULASKI-SALINE-SCOTT-VAN BUREN-WHITE-
WOODRUFF-YELL.
FLASH FLOOD WATCH UNTIL 7 AM CDT THIS MORNING FOR BAXTER-BOONE-
FULTON-IZARD-MARION-NEWTON-SEARCY-SHARP-STONE.
&&
$$
AVIATION...58
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
910 PM MDT SUN OCT 12 2014
.UPDATE...
ISSUED AT 910 PM MDT SUN OCT 12 2014
ROAD REPORTS AND WEB CAMS SUGGEST THAT SNOW OVER VAIL PASS
CONTINUES TO HAVE IMPACT...AND THE SAME HOLDS TRUE FOR MONARCH
PASS. THE SNOW MAY HAVE STOPPED OVER RABBIT EARS BUT RADAR STILL
SHOW SHOWERS NORTH OF HIGHWAY 40 AND MOVING SOUTHWARD. WILL LET
THE WINTER WEATHER ADVISORY PLAY OUT. SNOW HAS DIMINISHED OVER THE
NWRN SAN JUAN MOUNTAINS AND HAVE ALLOWED THE ADVISORY TO EXPIRE. A
FEW FLURRIES STILL ONGOING...BUT REMOTE SENSORS SUGGEST THE
SNOWFALL HAS PLAYED OUT.
UPDATE ISSUED AT 721 PM MDT SUN OCT 12 2014
WINDS HAVE DIMINISHED QUITE A BIT DURING THE PAST 1-2 HOURS.
FORECAST UPDATE TO CANCEL THE WIND ADVISORY FOR THE SOUTHERN
VALLEYS. SNOW SHOWERS WILL BE DIMINISHING AND IF CURRENT TREND
HOLDS...THE WINTER WEATHER ADVISORIES MAY BE CANCELLED EARLY BUT
STILL HAVING SOME IMPACT.
&&
.SHORT TERM...(TONIGHT THROUGH MONDAY NIGHT)
ISSUED AT 246 PM MDT SUN OCT 12 2014
ACTIVE WEATHER DAY CONTINUES WITH SNOW...RAIN...GUSTY WINDS...AND
THUNDERSTORMS ALL PLAYING A PART. THE COLD FRONT RESPONSIBLE FOR
THE PRECIP HAS ALREADY PUSHED OUT OF THE CWA AND DID SO FASTER
THAN ANTICIPATED. IN FACT...IT MOVED OVER DURANGO AROUND NOON
WHICH WAS SEVERAL HOURS QUICKER THAN ORIGINALLY FORECAST. EVEN
SO...THE ASSOCIATED SNOWFALL CAUSED SOME HEADACHES OVER MTN PASSES
ESPECIALLY VAIL PASS THAT WAS CLOSED FOR SOME TIME THIS MORNING
AND AFTERNOON. LOCAL SNOTELS SHOWING UPWARDS OF 6 INCHES HAVING
FALLEN NEAR TOWER AND SPOTTERS REPORTING AN INCH OR TWO AT MTN
BASES THOUGH THAT SNOW QUICKLY MELTED. UNSETTLED W TO NW FLOW HAS
SET UP BEHIND THE FRONT AND WILL KEEP PRECIP IN THE PICTURE
THROUGH THIS AFTN AND EVENING. ONE BIG DIFFERENCE FOR THIS TIME
FRAME IS THE ON AGAIN OFF AGAIN NATURE OF THE PRECIP DUE TO ITS
CONVECTIVE NATURE. WILL KEEP ADVISORIES IN PLACE. OF NOTE IS
LATEST RAP13 AND HRRR SHOWING PRECIP REALLY WINDING DOWN EARLY
THIS EVENING AS OPPOSED TO MIDNIGHT SO CHANCE DOES EXIST FOR SOME
WINTER HIGHLIGHTS TO BE PULLED DOWN EARLY.
PRESSURE GRADIENT REMAINS TIGHT AND REFLECTED IN ALMOST ALL AREAS
REPORTING WIND GUSTS. THESE GUSTS HAVE RANGED FROM 20 MPH TO 45
MPH AT THE DURANGO AIRPORT. THE WIND WILL SLOWLY START DYING DOWN
N OF I-70 A LITTLE AFTER 6PM WHILE AREAS SOUTH WILL BE A LITTLE
LATER. THE WIND ADVISORIES WILL CONTINUE. ALSO UPGRADED THE FREEZE
WATCH TO WARNINGS AS GUIDANCE STILL SHOWING BELOW FREEZING TEMPS
OVERNIGHT WHICH MAKES SENSE AS NORTHERLY FLOW WILL CONTINUE TO
USHER IN COLD AIR WHILE CLOUD COVER WILL DECREASE. A BRISK MORNING
IN STORE.
A LARGE AREA OF HIGH PRESSURE WILL BUILD IN MONDAY BRINGING A
PROLONGED PERIOD OF PRECIP-FREE WEATHER AND A WARMING TREND AS
DESCRIBED BELOW.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 246 PM MDT SUN OCT 12 2014
HIGH PRESSURE WILL CONTINUE TO BUILD OVER THE REGION TUESDAY
BRINGING VERY DRY AND PLEASANT AUTUMN CONDITIONS. THE RIDGE AXIS
MOVES EAST ON WEDNESDAY AS A PACIFIC NORTHWEST TROUGH MOVES
ONSHORE. SOUTHWEST WINDS WILL INCREASE OVER THE NORTHWESTERN PART
OF OUR FORECAST AREA WEDNESDAY MORNING AS THE PRESSURE GRADIENT
BETWEEN THE TROUGH AND RIDGE TIGHTENS. GOOD MODEL CONSENSUS ON THE
RIDGE FLATTENING AND COOLER AIR OVER NORTHERN UTAH AND COLORADO ON
THURSDAY BEFORE RIDGING STRENGTHENS AGAIN ON FRIDAY.
THE LONG RANGE FORECAST MODELS DIVERGE ON SATURDAY BUT BOTH KEEP
CONDITIONS DRY NEXT WEEKEND THROUGHOUT THE REGION.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 542 PM MDT SUN OCT 12 2014
IMPROVING CONDITIONS THIS EVENING WITH DISSIPATING RAIN OR SNOW
SHOWERS (SNOW LEVEL AROUND 7-8K FEET. LOCAL IFR FROM PASSING
SHOWERS BECOME WIDESPREAD VFR OVERNIGHT.
AS THE STRONG WINDS ALOFT SHIFT EAST...MODERATE MECHANICAL
TURBULENCE BECOMES LESS PROMINENT OVERNIGHT. SURFACE WIND BECOMES
LESS THAN 10 KTS BETWEEN 03Z-06Z THIS EVENING.
NO AVIATION HAZARDS ARE EXPECTED AFTER 09Z TONIGHT.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR COZ004-
010-012-013.
FREEZE WARNING FROM 2 AM TO 9 AM MDT MONDAY FOR COZ001-007-008-
020>022.
UT...NONE.
&&
$$
UPDATE...PF
SHORT TERM...TGR
LONG TERM...JAM
AVIATION...PF
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
721 PM MDT SUN OCT 12 2014
.UPDATE...
ISSUED AT 721 PM MDT SUN OCT 12 2014
WINDS HAVE DIMINISHED QUITE A BIT DURING THE PAST 1-2 HOURS.
FORECAST UPDATE TO CANCEL THE WIND ADVISORY FOR THE SOUTHERN
VALLEYS. SNOW SHOWERS WILL BE DIMINISHING AND IF CURRENT TREND
HOLDS...THE WINTER WEATHER ADVISORIES MAY BE CANCELLED EARLY BUT
STILL HAVING SOME IMPACT.
&&
.SHORT TERM...(TONIGHT THROUGH MONDAY NIGHT)
ISSUED AT 246 PM MDT SUN OCT 12 2014
ACTIVE WEATHER DAY CONTINUES WITH SNOW...RAIN...GUSTY WINDS...AND
THUNDERSTORMS ALL PLAYING A PART. THE COLD FRONT RESPONSIBLE FOR
THE PRECIP HAS ALREADY PUSHED OUT OF THE CWA AND DID SO FASTER
THAN ANTICIPATED. IN FACT...IT MOVED OVER DURANGO AROUND NOON
WHICH WAS SEVERAL HOURS QUICKER THAN ORIGINALLY FORECAST. EVEN
SO...THE ASSOCIATED SNOWFALL CAUSED SOME HEADACHES OVER MTN PASSES
ESPECIALLY VAIL PASS THAT WAS CLOSED FOR SOME TIME THIS MORNING
AND AFTERNOON. LOCAL SNOTELS SHOWING UPWARDS OF 6 INCHES HAVING
FALLEN NEAR TOWER AND SPOTTERS REPORTING AN INCH OR TWO AT MTN
BASES THOUGH THAT SNOW QUICKLY MELTED. UNSETTLED W TO NW FLOW HAS
SET UP BEHIND THE FRONT AND WILL KEEP PRECIP IN THE PICTURE
THROUGH THIS AFTN AND EVENING. ONE BIG DIFFERENCE FOR THIS TIME
FRAME IS THE ON AGAIN OFF AGAIN NATURE OF THE PRECIP DUE TO ITS
CONVECTIVE NATURE. WILL KEEP ADVISORIES IN PLACE. OF NOTE IS
LATEST RAP13 AND HRRR SHOWING PRECIP REALLY WINDING DOWN EARLY
THIS EVENING AS OPPOSED TO MIDNIGHT SO CHANCE DOES EXIST FOR SOME
WINTER HIGHLIGHTS TO BE PULLED DOWN EARLY.
PRESSURE GRADIENT REMAINS TIGHT AND REFLECTED IN ALMOST ALL AREAS
REPORTING WIND GUSTS. THESE GUSTS HAVE RANGED FROM 20 MPH TO 45
MPH AT THE DURANGO AIRPORT. THE WIND WILL SLOWLY START DYING DOWN
N OF I-70 A LITTLE AFTER 6PM WHILE AREAS SOUTH WILL BE A LITTLE
LATER. THE WIND ADVISORIES WILL CONTINUE. ALSO UPGRADED THE FREEZE
WATCH TO WARNINGS AS GUIDANCE STILL SHOWING BELOW FREEZING TEMPS
OVERNIGHT WHICH MAKES SENSE AS NORTHERLY FLOW WILL CONTINUE TO
USHER IN COLD AIR WHILE CLOUD COVER WILL DECREASE. A BRISK MORNING
IN STORE.
A LARGE AREA OF HIGH PRESSURE WILL BUILD IN MONDAY BRINGING A
PROLONGED PERIOD OF PRECIP-FREE WEATHER AND A WARMING TREND AS
DESCRIBED BELOW.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 246 PM MDT SUN OCT 12 2014
HIGH PRESSURE WILL CONTINUE TO BUILD OVER THE REGION TUESDAY
BRINGING VERY DRY AND PLEASANT AUTUMN CONDITIONS. THE RIDGE AXIS
MOVES EAST ON WEDNESDAY AS A PACIFIC NORTHWEST TROUGH MOVES
ONSHORE. SOUTHWEST WINDS WILL INCREASE OVER THE NORTHWESTERN PART
OF OUR FORECAST AREA WEDNESDAY MORNING AS THE PRESSURE GRADIENT
BETWEEN THE TROUGH AND RIDGE TIGHTENS. GOOD MODEL CONSENSUS ON THE
RIDGE FLATTENING AND COOLER AIR OVER NORTHERN UTAH AND COLORADO ON
THURSDAY BEFORE RIDGING STRENGTHENS AGAIN ON FRIDAY.
THE LONG RANGE FORECAST MODELS DIVERGE ON SATURDAY BUT BOTH KEEP
CONDITIONS DRY NEXT WEEKEND THROUGHOUT THE REGION.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 542 PM MDT SUN OCT 12 2014
IMPROVING CONDITIONS THIS EVENING WITH DISSIPATING RAIN OR SNOW
SHOWERS (SNOW LEVEL AROUND 7-8K FEET. LOCAL IFR FROM PASSING
SHOWERS BECOME WIDESPREAD VFR OVERNIGHT.
AS THE STRONG WINDS ALOFT SHIFT EAST...MODERATE MECHANICAL
TURBULENCE BECOMES LESS PROMINENT OVERNIGHT. SURFACE WIND BECOMES
LESS THAN 10 KTS BETWEEN 03Z-06Z THIS EVENING.
NO AVIATION HAZARDS ARE EXPECTED AFTER 09Z TONIGHT.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR COZ004-
010-012-013.
WINTER WEATHER ADVISORY UNTIL 9 PM MDT THIS EVENING FOR COZ018.
FREEZE WARNING FROM 2 AM TO 9 AM MDT MONDAY FOR COZ001-007-008-
020>022.
UT...NONE.
&&
$$
UPDATE...PF
SHORT TERM...TGR
LONG TERM...JAM
AVIATION...PF
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
542 PM MDT SUN OCT 12 2014
.SHORT TERM...(TONIGHT THROUGH MONDAY NIGHT)
ISSUED AT 246 PM MDT SUN OCT 12 2014
ACTIVE WEATHER DAY CONTINUES WITH SNOW...RAIN...GUSTY WINDS...AND
THUNDERSTORMS ALL PLAYING A PART. THE COLD FRONT RESPONSIBLE FOR
THE PRECIP HAS ALREADY PUSHED OUT OF THE CWA AND DID SO FASTER
THAN ANTICIPATED. IN FACT...IT MOVED OVER DURANGO AROUND NOON
WHICH WAS SEVERAL HOURS QUICKER THAN ORIGINALLY FORECAST. EVEN
SO...THE ASSOCIATED SNOWFALL CAUSED SOME HEADACHES OVER MTN PASSES
ESPECIALLY VAIL PASS THAT WAS CLOSED FOR SOME TIME THIS MORNING
AND AFTERNOON. LOCAL SNOTELS SHOWING UPWARDS OF 6 INCHES HAVING
FALLEN NEAR TOWER AND SPOTTERS REPORTING AN INCH OR TWO AT MTN
BASES THOUGH THAT SNOW QUICKLY MELTED. UNSETTLED W TO NW FLOW HAS
SET UP BEHIND THE FRONT AND WILL KEEP PRECIP IN THE PICTURE
THROUGH THIS AFTN AND EVENING. ONE BIG DIFFERENCE FOR THIS TIME
FRAME IS THE ON AGAIN OFF AGAIN NATURE OF THE PRECIP DUE TO ITS
CONVECTIVE NATURE. WILL KEEP ADVISORIES IN PLACE. OF NOTE IS
LATEST RAP13 AND HRRR SHOWING PRECIP REALLY WINDING DOWN EARLY
THIS EVENING AS OPPOSED TO MIDNIGHT SO CHANCE DOES EXIST FOR SOME
WINTER HIGHLIGHTS TO BE PULLED DOWN EARLY.
PRESSURE GRADIENT REMAINS TIGHT AND REFLECTED IN ALMOST ALL AREAS
REPORTING WIND GUSTS. THESE GUSTS HAVE RANGED FROM 20 MPH TO 45
MPH AT THE DURANGO AIRPORT. THE WIND WILL SLOWLY START DYING DOWN
N OF I-70 A LITTLE AFTER 6PM WHILE AREAS SOUTH WILL BE A LITTLE
LATER. THE WIND ADVISORIES WILL CONTINUE. ALSO UPGRADED THE FREEZE
WATCH TO WARNINGS AS GUIDANCE STILL SHOWING BELOW FREEZING TEMPS
OVERNIGHT WHICH MAKES SENSE AS NORTHERLY FLOW WILL CONTINUE TO
USHER IN COLD AIR WHILE CLOUD COVER WILL DECREASE. A BRISK MORNING
IN STORE.
A LARGE AREA OF HIGH PRESSURE WILL BUILD IN MONDAY BRINGING A
PROLONGED PERIOD OF PRECIP-FREE WEATHER AND A WARMING TREND AS
DESCRIBED BELOW.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 246 PM MDT SUN OCT 12 2014
HIGH PRESSURE WILL CONTINUE TO BUILD OVER THE REGION TUESDAY
BRINGING VERY DRY AND PLEASANT AUTUMN CONDITIONS. THE RIDGE AXIS
MOVES EAST ON WEDNESDAY AS A PACIFIC NORTHWEST TROUGH MOVES
ONSHORE. SOUTHWEST WINDS WILL INCREASE OVER THE NORTHWESTERN PART
OF OUR FORECAST AREA WEDNESDAY MORNING AS THE PRESSURE GRADIENT
BETWEEN THE TROUGH AND RIDGE TIGHTENS. GOOD MODEL CONSENSUS ON THE
RIDGE FLATTENING AND COOLER AIR OVER NORTHERN UTAH AND COLORADO ON
THURSDAY BEFORE RIDGING STRENGTHENS AGAIN ON FRIDAY.
THE LONG RANGE FORECAST MODELS DIVERGE ON SATURDAY BUT BOTH KEEP
CONDITIONS DRY NEXT WEEKEND THROUGHOUT THE REGION.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 542 PM MDT SUN OCT 12 2014
IMPROVING CONDITIONS THIS EVENING WITH DISSIPATING RAIN OR SNOW
SHOWERS (SNOW LEVEL AROUND 7-8K FEET. LOCAL IFR FROM PASSING
SHOWERS BECOME WIDESPREAD VFR OVERNIGHT.
AS THE STRONG WINDS ALOFT SHIFT EAST...MODERATE MECHANICAL
TURBULENCE BECOMES LESS PROMINENT OVERNIGHT. SURFACE WIND BECOMES
LESS THAN 10 KTS BETWEEN 03Z-06Z THIS EVENING.
NO AVIATION HAZARDS ARE EXPECTED AFTER 09Z TONIGHT.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WIND ADVISORY UNTIL 9 PM MDT THIS EVENING FOR COZ021-022.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR COZ004-
010-012-013.
WINTER WEATHER ADVISORY UNTIL 9 PM MDT THIS EVENING FOR COZ018.
FREEZE WARNING FROM 2 AM TO 9 AM MDT MONDAY FOR COZ001-007-008-
020>022.
UT...WIND ADVISORY UNTIL 9 PM MDT THIS EVENING FOR UTZ022-029.
&&
$$
SHORT TERM...TGR
LONG TERM...JAM
AVIATION...PF
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
926 AM MDT SAT OCT 11 2014
.UPDATE...
ISSUED AT 918 AM MDT SAT OCT 11 2014
STUBBORN AREA OF FOG OVER CENTRAL WELD COUNTY FINALLY SHOWING SOME
SIGNS OF LIFTING THIS MORNING. HAVE UPDATED TO KEEP FOG IN THE
GRIDS THROUGH LATE THIS MORNING NORTH OF DENVER. ALSO OPTED TO ADD
THE POTENTIAL FOR SOME THUNDER THIS AFTERNOON. BEST AREA ACCORDING
TO THE LATEST HRRR MAY BE OVER THE PALMER DIVIDE. A WEAK
DISTURBANCE DROPPING OUT OF WY BROUGHT SOME LIGHT RAIN SHOWERS AND
ONE LTG STRIKE TO NORTHERN LARIMER COUNTY THIS MORNING...SO HAVE
ADDED SOME ISOLATED POPS THERE AS WELL. THIS FEATURE MAY ALSO HELP
TO BREAK UP THE AREA OF FOG AS WELL THIS MORNING.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 330 AM MDT SAT OCT 11 2014
FOR THIS MORNING THERE WILL BE AREAS OF PATCHY FOG OVER THE PLAINS.
THE HRRR INDICATES THERE COULD BE SOME DENSE FOG ALONG THE SOUTH
PLATTE RIVER VALLEY IN THE 10Z-15Z TIMEFRAME.
FOR THIS AFTN INTO THE EARLY EVENING HOURS A WEAK DISTURBANCE IN
NWLY FLOW ALOFT WILL MOVE ACROSS THE AREA. THERE IS SOME MID LVL
MOISTURE WITH THIS FEATURE AND WITH LAPSE RATES BETWEEN 7.5 AND 8.5
C/KM WILL SEE AT LEAST WDLY SCT SHOWERS OVER THE HIGHER TERRAIN. AT
LOWER ELEVATIONS THERE COULD ALSO BE SOME WDLY SCT HIGH BASED
SHOWERS LATE THIS AFTN INTO THE EARLY EVENING SO WILL MENTION LOW
POPS ALONG THE FRONT RANGE AND NR THE WY BORDER. AS FOR HIGHS 850-
700 MB TEMPS RISE QUITE A BIT TODAY SO WILL KEEP READINGS IN THE
LOWER TO MID 70S AROUND DENVER WITH UPPER 60S TO LOWER 70S OVER THE
REST OF THE PLAINS.
BY TONIGHT THE WK DISTURBANCE WILL MOVE SE OF THE AREA AS STRONGER
FLOW ALOFT DEVELOPS IN ADVANCE OF A STRONGER SYSTEM WHICH WILL
AFFECT THE RGN ON SUN. CROSS-SECTIONS SHOW LIMITED MOISTURE
OVERNIGHT SO WILL ONLY MENTION A SLIGHT CHC OF SHOWERS IN THE MTNS.
WITH INCREASING FLOW ALOFT GUSTY WINDS WILL DVLP IN THE MTNS AND
HIGHER FOOTHILLS AFTER MIDNIGHT BUT SPEEDS SHOULD STAY BLO WARNING
CRITERIA.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 330 AM MDT SAT OCT 11 2014
MODELS HAVE AN UPPER TROUGH AXIS TO MOVE ACROSS THE CWA SUNDAY
WITH A NORTH-NORTHWESTERLY JET MAXIMUM TO MOVE ACROSS LATE SUNDAY
NIGHT AND MONDAY MORNING. MONDAY NIGHT SHOWS DECREASING NORTHWESTERLY
FLOW ALOFT FOR THE FORECAST AREA. THE QG VERTICAL VELOCITY FIELDS
SHOW A PERIOD OF DECENT UPWARD MOTION FOR US ON SUNDAY. PRETTY
STRONG DOWNWARD MOTION IS INDICATE LATER SUNDAY EVENING INTO
EARLY MONDAY AFTERNOON. THE BOUNDARY LAYER FLOW BECOMES NORTH-
NORTHWESTERLY FOR MUCH OF THE CWA ON SUNDAY INTO THE EVENING
...THEN MORE NORTHWESTERLY OVERNIGHT SUNDAY NIGHT THROUGH MONDAY.
THE COLD FRONT STILL LOOKS TO GET INTO THE PLAINS AROUND NOONTIME.
NORMAL DRAINAGE PATTERNS MAY RETURN FOR MONDAY NIGHT. THERE IS
CERTAINLY SOME MOISTURE AROUND WITH SUNDAY`S UPPER TROUGH
CONTINUING INTO THE EVENING...THEN THINGS DRY OUT PRETTY WELL
MONDAY AND MONDAY NIGHT. DEW POINT PROGS HAVE READINGS MAINLY IN
THE 30S F ON SUNDAY...THEN THE 20S F ON MONDAY. THERE IS A TAD OF
CAPE PROGGED SUNDAY AFTERNOON...THEN NONE MONDAY AND MONDAY NIGHT.
THE QPF FIELDS HAVE MEASURABLE PRECIPITATION SUNDAY INTO SUNDAY
EVENING...NOTHING SIGNIFICANT HOWEVER. THE SNOW LEVEL LOOKS A BIT
HIGHER THAN IT DID FROM THE PREVIOUS RUNS. THERE COULD BE SOME
SNOW AS LOW AS 7000 MSL BY LATE SUNDAY AFTERNOON AND EVENING...BUT
POPS WILL BE ON THE DECREASE AFTER SUNSET. FOR POPS...WILL NOT
CHANGE SUNDAY AND SUNDAY EVENING VERY MUCH. THE HIGH COUNTY WILL
SEE 50-80%S WITH THE TROUGH...NOTHING ABOVE 50%S FOR THE PLAINS
RIGHT NOW. SEE NO REASON FOR HIGHLIGHTS RIGHT NOW. FOR
TEMPERATURES...SUNDAY`S HIGHS ARE DOWN UP TO 10C FROM TODAY`S
HIGHS. MONDAY`S HIGHS WARM UP 2-4 C FROM SUNDAY`S. FOR THE LATER
DAYS...TUESDAY THROUGH FRIDAY...THERE IS UPPER RIDGING OR FLAT
UPPER RIDGING OVER THE CWA ALL FOUR DAYS. MOISTURE IS POOR AND
TEMPERATURES ARE ABOVE NORMAL.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z SUNDAY MORNING)
ISSUED AT 918 AM MDT SAT OCT 11 2014
WNDS WILL REMAIN DRAINAGE THRU THE MORNING HOURS WITH ANY FOG
STAYING NORTH OF THE AIRPORT. BY MIDDAY WINDS WINDS WILL BECOME
MORE SSE. AFTER 21Z THERE COULD BE A WIND SHIFT TO A MORE WLY
DIRECTION AS OUTFLOW FM SOME HIGH BASED SHOWERS MOVES ACROSS.
AFTER 01Z WINDS SHOULD BECOME MORE SLY AND THEN SSW BY 04Z. HAVE
ADDED ISOLD THUNDERSTORMS TO THE PUBLIC FORECAST THIS AFTN BUT
WILL KEEP VCSH IN THE TAFS FOR NOW...BEST INSTABILITY FOR ANY
TSTMS MAY BE MORE WEST AND SOUTH OF DENVER THIS AFTN.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...COOPER
SHORT TERM...RPK
LONG TERM...RJK
AVIATION...COOPER
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
336 AM MDT SAT OCT 11 2014
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 330 AM MDT SAT OCT 11 2014
FOR THIS MORNING THERE WILL BE AREAS OF PATCHY FOG OVER THE PLAINS.
THE HRRR INDICATES THERE COULD BE SOME DENSE FOG ALONG THE SOUTH
PLATTE RIVER VALLEY IN THE 10Z-15Z TIMEFRAME.
FOR THIS AFTN INTO THE EARLY EVENING HOURS A WEAK DISTURBANCE IN
NWLY FLOW ALOFT WILL MOVE ACROSS THE AREA. THERE IS SOME MID LVL
MOISTURE WITH THIS FEATURE AND WITH LAPSE RATES BETWEEN 7.5 AND 8.5
C/KM WILL SEE AT LEAST WDLY SCT SHOWERS OVER THE HIGHER TERRAIN. AT
LOWER ELEVATIONS THERE COULD ALSO BE SOME WDLY SCT HIGH BASED
SHOWERS LATE THIS AFTN INTO THE EARLY EVENING SO WILL MENTION LOW
POPS ALONG THE FRONT RANGE AND NR THE WY BORDER. AS FOR HIGHS 850-
700 MB TEMPS RISE QUITE A BIT TODAY SO WILL KEEP READINGS IN THE
LOWER TO MID 70S AROUND DENVER WITH UPPER 60S TO LOWER 70S OVER THE
REST OF THE PLAINS.
BY TONIGHT THE WK DISTURBANCE WILL MOVE SE OF THE AREA AS STRONGER
FLOW ALOFT DEVELOPS IN ADVANCE OF A STRONGER SYSTEM WHICH WILL
AFFECT THE RGN ON SUN. CROSS-SECTIONS SHOW LIMITED MOISTURE
OVERNIGHT SO WILL ONLY MENTION A SLIGHT CHC OF SHOWERS IN THE MTNS.
WITH INCREASING FLOW ALOFT GUSTY WINDS WILL DVLP IN THE MTNS AND
HIGHER FOOTHILLS AFTER MIDNIGHT BUT SPEEDS SHOULD STAY BLO WARNING
CRITERIA.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 330 AM MDT SAT OCT 11 2014
MODELS HAVE AN UPPER TROUGH AXIS TO MOVE ACROSS THE CWA SUNDAY
WITH A NORTH-NORTHWESTERLY JET MAXIMUM TO MOVE ACROSS LATE SUNDAY
NIGHT AND MONDAY MORNING. MONDAY NIGHT SHOWS DECREASING NORTHWESTERLY
FLOW ALOFT FOR THE FORECAST AREA. THE QG VERTICAL VELOCITY FIELDS
SHOW A PERIOD OF DECENT UPWARD MOTION FOR US ON SUNDAY. PRETTY
STRONG DOWNWARD MOTION IS INDICATE LATER SUNDAY EVENING INTO
EARLY MONDAY AFTERNOON. THE BOUNDARY LAYER FLOW BECOMES NORTH-
NORTHWESTERLY FOR MUCH OF THE CWA ON SUNDAY INTO THE EVENING
...THEN MORE NORTHWESTERLY OVERNIGHT SUNDAY NIGHT THROUGH MONDAY.
THE COLD FRONT STILL LOOKS TO GET INTO THE PLAINS AROUND NOONTIME.
NORMAL DRAINAGE PATTERNS MAY RETURN FOR MONDAY NIGHT. THERE IS
CERTAINLY SOME MOISTURE AROUND WITH SUNDAY`S UPPER TROUGH
CONTINUING INTO THE EVENING...THEN THINGS DRY OUT PRETTY WELL
MONDAY AND MONDAY NIGHT. DEW POINT PROGS HAVE READINGS MAINLY IN
THE 30S F ON SUNDAY...THEN THE 20S F ON MONDAY. THERE IS A TAD OF
CAPE PROGGED SUNDAY AFTERNOON...THEN NONE MONDAY AND MONDAY NIGHT.
THE QPF FIELDS HAVE MEASURABLE PRECIPITATION SUNDAY INTO SUNDAY
EVENING...NOTHING SIGNIFICANT HOWEVER. THE SNOW LEVEL LOOKS A BIT
HIGHER THAN IT DID FROM THE PREVIOUS RUNS. THERE COULD BE SOME
SNOW AS LOW AS 7000 MSL BY LATE SUNDAY AFTERNOON AND EVENING...BUT
POPS WILL BE ON THE DECREASE AFTER SUNSET. FOR POPS...WILL NOT
CHANGE SUNDAY AND SUNDAY EVENING VERY MUCH. THE HIGH COUNTY WILL
SEE 50-80%S WITH THE TROUGH...NOTHING ABOVE 50%S FOR THE PLAINS
RIGHT NOW. SEE NO REASON FOR HIGHLIGHTS RIGHT NOW. FOR
TEMPERATURES...SUNDAY`S HIGHS ARE DOWN UP TO 10C FROM TODAY`S
HIGHS. MONDAY`S HIGHS WARM UP 2-4 C FROM SUNDAY`S. FOR THE LATER
DAYS...TUESDAY THROUGH FRIDAY...THERE IS UPPER RIDGING OR FLAT
UPPER RIDGING OVER THE CWA ALL FOUR DAYS. MOISTURE IS POOR AND
TEMPERATURES ARE ABOVE NORMAL.
&&
.AVIATION...(FOR THE TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 330 AM MDT SAT OCT 11 2014
WNDS WILL REMAIN DRAINAGE THRU THE MORNING HOURS WITH ANY FOG
STAYING NORTH OF THE AIRPORT. BY MIDDAY WINDS WINDS WILL BECOME
MORE SSE. AFTER 21Z THERE COULD BE A WIND SHIFT TO A MORE WLY
DIRECTION AS OUTFLOW FM SOME HIGH BASED SHOWERS MOVES ACROSS.
AFTER 01Z WINDS SHOULD BECOME MORE SLY AND THEN SSW BY 04Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RPK
LONG TERM...RJK
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
340 AM EDT SAT OCT 11 2014
.SYNOPSIS...
07Z WATER VAPOR AND H4 RAP ANALYSIS CONTINUE TO SHOW AN OVERALL
UNAMPLIFIED UPPER LEVEL PATTERN ACROSS THE CONUS EARLY THIS MORNING.
HOWEVER...THIS MORE BENIGN UPPER LEVEL PATTERN WILL NOT LAST.
ALREADY SEEING SHORTWAVE ENERGY ARRIVING WITHIN THE NORTHERN STREAM
FLOW APPROACHING THE BRITISH COLUMBIA COAST THAT WILL EVOLVE OVER
THE NEXT 72 TO 84 HOURS INTO AN IMPRESSIVE DEEP AND SHARP TROUGH
OVER THE MID-SECTION OF THE COUNTRY...RESULTING IN WIDESPREAD
INCLEMENT WEATHER. HOWEVER...LETS NOT GET AHEAD OF OURSELVES...BACK
TO THE PRESENT.
CURRENT PATTERN SHOWS SPLIT FLOW ARRIVING OVER THE PACIFIC
NORTHWEST...WITH ONE BRANCH RIDING UP INTO THE CANADIAN
ROCKIES...AND THE OTHER DROPPING SOUTH THROUGH THE GREAT BASIN
REGION. THE DOWNSTREAM FLOW THEN BECOMES CONVERGENT AGAIN ACROSS THE
MID-SECTION OF THE COUNTRY AND RIDES NORTHEASTWARD OFF THE
MID-ATLANTIC/NEW ENGLAND COASTS TO THE SOUTH OF AN EASTERN CANADIAN
TROUGH. THE ONLY REAL "WEATHER" IN THE COUNTY EXISTS WITH A SERIES
OF SHORTWAVE EJECTING WITH THE FLOW OUT OF THE SOUTHWESTERN STATES
AND ACROSS THE SOUTHERN/CENTRAL PLAINS. THESE IMPULSES ARE RESULTING
IN CLUSTERS OF SHOWERS/STORMS FROM NORTHERN TEXAS/OK TO THE LOWER MS
VALLEY.
CLOSER TO HOME WE FIND A BROAD EXPANSE OF MID/UPPER LEVEL RIDGING IN
PLACE OVER THE GULF OF MEXICO AND FL PENINSULA. SYNOPTIC SUPPRESSION
WITHIN THIS RIDGE IS RESULTING IN A DRY COLUMN ABOVE THE BOUNDARY
LAYER AS SEEN IN WV IMAGERY AND WITH THE 11/00Z KTBW SOUNDING
PROFILE.
AT THE SURFACE...RIDGE OF HIGH PRESSURE EXTENDS FROM OFF THE
CAROLINA COAST BACK SOUTHWEST TO THE I-10 CORRIDOR. OUR REGION
RESIDES IN A ZONE OF EASTERLY SYNOPTIC FLOW TO THE SOUTH OF THIS
RIDGE AXIS.
&&
.SHORT TERM (TODAY THROUGH SUNDAY)...
THE QUIET WEATHER UNDERNEATH STACKED RIDGING CONTINUES FOR THE
DURATION OF THE WEEKEND. VERY LITTLE HAS CHANGED FROM A SYNOPTIC
VIEW FROM FRIDAY INTO TODAY. WE ARE STILL LOOKING AT A DRY COLUMN
FROM NORTH TO SOUTH ABOVE SHALLOW BOUNDARY LAYER MOISTURE ARRIVING
FROM THE ATLANTIC WITHIN THE EASTERLY LOW LEVEL FLOW. ON FRIDAY WE
WERE ONLY ABLE TO POP ONE OR TWO VERY ISOLATED AND BRIEF SHOWERS
OVER THE NATURE COAST...AND APPEARS AS THOUGH THE COLUMN WILL BE
EVEN A TOUCH MORE HOSTILE TOWARD DEEP CONVECTION TODAY. DEEP LAYER
DEWPOINT DEPRESSIONS ARE RATHER LARGE ABOVE 850MB...AND THERE IS A
DEEP LAYER OF SUB 320K THETAE IN THE MID-LEVELS. ALL OF THIS WILL BE
VERY DIFFICULT FOR CONVECTIVE COLUMNS TO OVERCOME AND GROW TO THE
POINT OF PRECIPITATION. SIMILAR TO FRIDAY...WILL SAY A VERY ISOLATED
SHOWER CAN NOT BE RULE COMPLETELY OUT...BUT COVERAGE SUGGESTS
VIRTUALLY ALL OF US WILL BE RAIN FREE TODAY...AND ONCE AGAIN WILL
NOT MENTION SHOWERS IN THE FORECAST...KEEPING ALL RAIN CHANCES AT
10% OR LESS.
EFFICIENT MIXING UP TO BETWEEN 800-850MB SHOULD MIX OUT AFTERNOON
HIGH TEMPERATURES INTO THE UPPER UPPER 80S AND LOWER 90S...WHICH IS
JUST A FEW DEGREES ABOVE AVERAGE FOR THE MIDDLE OF OCTOBER.
LOOKING AT THE WIND SPEEDS JUST ABOVE THE SURFACE...950-925MB WINDS
THIS AFTERNOON ARE GENERALLY AT OR BELOW 10 KNOTS ABOVE THE SUN AND
NATURE COASTS. GENERALLY SPEAKING THIS IS NOT ENOUGH OPPOSING FLOW
TO HOLD BACK THE SEA-BREEZE FROM COMING ASHORE. DO NOT ANTICIPATE
MUCH INLAND PENETRATION...BUT WITH THE DEGREE OF TERRESTRIAL HEATING
ANTICIPATED TODAY...WOULD EXPECT WINDS TO FLIP AROUND TO A NW
DIRECTION AT THE BEACHES AFTER 1-2PM.
TONIGHT...MORE OF THE SAME WITH DRY CONDITIONS AND SEASONABLE OR
SLIGHTLY ABOVE AVERAGE LOW TEMPERATURES. WILL BE EXPECTING AREAS OF
FOG TO DEVELOP AFTER MIDNIGHT...WITH AN EMPHASIS COVERAGE TO THE
NORTH OF I-4...WHERE THE BOUNDARY LAYER WINDS ARE WEAKEST CLOSE TO
THE RIDGE AXIS.
SUNDAY IS SHAPING UP TO BE ANOTHER MOSTLY DRY AND WARM DAY TO CLOSE
OUT THE WEEKEND. LATE IN THE DAY ON SUNDAY WE WILL BEGIN TO SEE THE
VERY BEGINNING OF THE TRANSITION TOWARD THE RETURN OF MOISTURE OVER
THE SOUTHERN THIRD OF THE STATE. WE WILL STILL BE UNDER THE
INFLUENCE OF STACKED RIDGING...ALTHOUGH THE UPPER RIDGE WILL BE
SHOWING SIGNS OF BEGINNING TO SHIFT TO THE EAST. THE CONTINUED
SUPPRESSIVE ENVIRONMENT WILL KEEP ALMOST ALL OF THE FORECAST AREA
DRY/RAIN FREE FOR ANOTHER DAY...WITH HIGH TEMPERATURES UP AROUND 90.
TIME-HEIGHT ANALYSIS/X-SECTIONS FROM NORTH TO SOUTH SHOW A SLIGHT
INFLUX OF MOISTURE INTO THE SOUTHERN THIRD OF THE STATE DURING THE
LATER PORTION OF THE DAY. MAINLY SEEING THE HOSTILE THETAE
ENVIRONMENT DOWN TOWARD LEE COUNTY LET UP A BIT. WILL IT BE ENOUGH
TO ALLOW A FEW STORM TO POP AFTER 20Z? BEST GUESS (ASSUMING THE
MODEL TIMING IS CORRECT) IS THAT THE MAJORITY OF ANY SHOWERS THAT DO
FORM WILL BE SOUTH OF FORT MYERS...BUT WILL BE CONSERVATIVE AND
ALLOW A 20% SLIGHT RAIN CHANCE UP INTO LEE COUNTY FOR THE LATE DAY
HOURS. ELSEWHERE...WILL KEEP IT DRY.
LOOKING WELL TO OUR WEST...STRONG SHORTWAVE ENERGY DIVING INTO THE
CENTRAL PORTION OF THE COUNTRY WILL BE STARTING TO DIG AN IMPRESSIVE
TROUGH FOR THIS TIME OF YEAR BY THE END OF THE DAY INTO SUNDAY
NIGHT. THIS FEATURE WILL RESULT IN THE EVENTUAL ARRIVAL OF A COLD
FRONT INTO OUR REGION BY THE MIDDLE OF THE WEEK. MORE ON THIS CHANGE
IN PATTERN IN THE LONG TERM DISCUSSION BELOW.
&&
.LONG TERM (MONDAY THROUGH NEXT FRIDAY)...
THE PERIOD BEGINS WITH A CANADIAN TROUGH REACHING DOWN ACROSS THE
NORTHERN AND CENTRAL U.S. PLAINS WHILE DEEP LAYER RIDGING RESIDES
ALONG THE EASTERN SEA BOARD AND DOWN INTO THE EAST GULF OF MEXICO.
FOR MON AND TUE THESE FEATURES SLIDE EAST...WITH THE TROUGH
EXTENDING DOWN TO THE GULF AND DEEPENING INTO A CLOSED LOW OVER THE
MID-MISSISSIPPI VALLEY (11/00Z ECMWF) OR THE UPPER GREAT LAKES
(11/00Z GFS). THE SURFACE REFLECTION OF THE UPPER LOW TRAILS A COLD
THAT STRETCHES ACROSS THE SOUTHEASTERN STATE AND OVER THE EASTERN
GULF WITH THE ECMWF MORE ROBUST AND SLIGHTLY SLOWER THAN THE GFS.
ON WED AND THU THE UPPER LOW TAKES A EAST-NORTHEAST TRACK WITH THE
ECMWF CONTINUING TO BE SLOWER AND STRONGER. THE TRAILING FRONT
SLIDES SOUTHWARD ACROSS FL...REACHING SOUTH FL BY THU. FINALLY BY
FRI THE LOW HAS DAMPENED OUT NORTH OF THE GREAT LAKES OR THE SAINT
LAWRENCE VALLEY WHILE SOME DEEP RIDGING BUILDS ACROSS THE GULF
REGION FROM THE WEST.
THE PRESENT FORECAST PHILOSOPHY IS TO BLEND THE GFS AND ECMWF ALONG
WITH THE CANADIAN MODEL. INCREASING SOUTHEASTERLY FLOW WILL BRING IN
ENOUGH MOISTURE FOR SLIGHT CHANCE TO CHANCE POP MON AFTERNOON WITH
THE HIGHEST ODDS IN THE SOUTH. THE LOW LEVEL FLOW BECOMES MORE
SOUTHERLY MON NIGHT AND TUE WITH ADDITIONAL MOISTURE WHICH ALONG
WITH THE APPROACHING FRONT WILL SUPPORT SCATTERED TO LIKELY SHOWERS
AND THUNDERSTORMS SPREADING IN FROM THE WEST AND NORTHWEST. SOME OF
THESE STORMS COULD BE STRONG ALTHOUGH THE BEST ENERGY AND MOISTURE
WILL BE TO THE NORTH. THE RAIN CHANCES BEGINS TO TAPER OFF TUE NIGHT
AND WED AS THE FRONT CROSSES THE AREA AND SOME DRIER AIR WORKS IN
FROM THE NORTHWEST. FOR THU AND FRI ANY SIGNIFICANT PRECIPITATION
WILL BE WELL TO THE EAST AND SOUTHEAST. TEMPERATURES COOL OFF BUT
STAY ON THE WARM SIDE OF NORMAL.
&&
.AVIATION...
HIGH PRESSURE WILL REMAIN IN CONTROL OF THE REGION THROUGH THE TAF
PERIOD WITH MAINLY DRY AND RAIN FREE CONDITIONS. SIMILAR TO PREVIOUS
NIGHTS...AREAS OF FOG WILL EXPAND THROUGH THE PRE DAWN
HOURS...MAINLY TO THE NORTH OF I-4...HOWEVER A PERIOD OF MVFR VIS IS
EXPECTED AT KLAL AND PERHAPS AS FAR SOUTH AS KPGD. ANY FOG WILL
QUICKLY BURN OFF WITHIN AN HOUR OR 2 OF SUNRISE WITH PREVAILING VFR
CONDITIONS THEREAFTER. AREAS OF MVFR VIS WILL AGAIN DEVELOP FOR THE
SECOND HALF OF SATURDAY NIGHT WITH KLAL AND KPGD SEEING THE BEST
CHANCES FOR ANY VISIBILITY RESTRICTIONS.
&&
.MARINE...
HIGH PRESSURE WILL REMAIN JUST TO THE NORTH OF THE FORECAST WATERS
THROUGH THE WEEKEND. THE PREVAILING FLOW WILL BE FROM THE
EAST...ALTHOUGH WINDS WILL LIKELY VEER AROUND TO THE NW NEAR THE
COAST EACH AFTERNOON...AND THEN QUICKLY SWITCH BACK FROM THE EAST
AFTER SUNSET. A NOCTURNAL WIND SURGE WILL APPROACH 15 KNOTS FOR A
TIME TONIGHT...MAINLY TO THE SOUTH OF TARPON SPRINGS. THE GRADIENT
WILL THEN TIGHTEN EARLY NEXT WEEK BETWEEN HIGH PRESSURE TO OUR EAST
AND AN APPROACHING COLD FRONT FROM THE WEST...WITH AN INCREASE IN
WINDS AND SEAS FROM THE SOUTHEAST. THIS FRONT IS EXPECTED TO ARRIVE
DURING TUESDAY OR TUESDAY NIGHT...WITH A SHIFT IN WINDS TO THE NORTH
IN ITS WAKE FOR THE MIDDLE PORTION OF THE WEEK.
&&
.FIRE WEATHER...
HIGH PRESSURE WILL REMAIN IN CONTROL OF THE REGION THROUGH THE
WEEKEND KEEPING OUR WEATHER GENERALLY WARM AND RAIN FREE. DESPITE
THE DRIER CONDITIONS...RELATIVE HUMIDITY VALUES ARE EXPECTED TO
REMAIN ABOVE CRITICAL LEVELS. NO SIGNIFICANT FIRE WEATHER CONCERNS
ARE ANTICIPATED.
AREAS OF GROUND FOG ARE EXPECTED TO DEVELOP AFTER MIDNIGHT SATURDAY
NIGHT INTO EARLY SUNDAY MORNING...ESPECIALLY ALONG AND TO THE NORTH
OF THE I-4 CORRIDOR. ALTHOUGH AREAS OF FOG ARE EXPECTED...WIDESPREAD
DENSE FOG IS NOT ANTICIPATED. FOG IS NOT EXPECTED TO BE A CONCERN
SUNDAY NIGHT OR MONDAY NIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 90 72 91 72 / 0 0 10 10
FMY 91 71 90 73 / 0 0 20 10
GIF 90 70 90 68 / 10 0 10 0
SRQ 89 71 89 72 / 0 10 10 10
BKV 91 63 90 67 / 0 0 0 0
SPG 89 75 90 75 / 0 0 10 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...MROCZKA
LONG TERM...RUDE
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1109 AM EDT SAT OCT 11 2014
.SYNOPSIS...
ABOVE NORMAL TEMPERATURES WILL BE FELT ACROSS THE REGION AGAIN TODAY.
THE FRONTAL BOUNDARY WILL SLIP SOUTH ACROSS THE MIDLANDS LATE
THIS AFTERNOON AND TONIGHT. COOL HIGH PRESSURE WILL RIDGE IN FROM THE
NORTH SUNDAY. A STRONG COLD FRONT WILL CROSS THE AREA LATE TUESDAY
AND TUESDAY NIGHT WITH WIDESPREAD SHOWERS AND THUNDERSTORMS. COOL
TEMPERATURES WILL FOLLOW FOR THE END OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
NEARLY ZONAL WESTERLY UPPER LEVEL FLOW ACROSS THE EASTERN PART OF
THE COUNTRY WILL BEGIN TO AMPLIFY TONIGHT AS A POSITIVELY TILTED
TROUGH DIGS INTO THE UPPER MIDWEST. A FRONTAL BOUNDARY EXTENDED
FROM CENTRAL TEXAS NORTHEASTWARD INTO THE TENNESSEE VALLEY TO
SOUTHERN VIRGINIA.
LATEST RADAR IMAGERY CONTINUES TO SHOW SHOWERS AND THUNDERSTORMS
NORTH AND WEST OF THE MIDLANDS FROM NORTHEAST GA INTO THE UPSTATE
OF SC. MESO ANALYSIS SHOWED LIFTED INDICES AROUND MINUS 3C ACROSS
THE CSRA...AND THE RAP AND NAM MODELS INDICATED THIS AREA OF
INSTABILITY TO SPREAD INTO THE MIDLANDS. WITH THE CONVECTION TO
THE NORTH AND WEST SLOWLY MOVING EASTWARD AND AFTERNOON
INSTABILITY THERE IS A SLIGHT CHANCE FOR SHOWERS AND THUNDERSTORMS
ACROSS THE AREA BUT MORE LIKELY NORTH OF THE I-20 CORRIDOR.
KEPT TEMPERATURES IN THE MID 80S TO AROUND 90...WHICH IS IN LINE
WITH GUIDANCE CONSENSUS.
THE FRONTAL BOUNDARY IS FORECAST TO PUSH SOUTH THROUGH THE MIDLANDS
LATE THIS AFTERNOON AND TONIGHT THEN STALL NEAR OR JUST SOUTH OF
THE CSRA. SURFACE HIGH PRESSURE OVER NEW ENGLAND WILL RIDGE INTO
THE CAROLINAS RESULTING IN A SHALLOW WEDGE/COLD AIR DAMMING
OVERNIGHT. WEAK ISENTROPIC LIFT COULD RESULT IN SPOTTY LIGHT RAIN
AND DRIZZLE TONIGHT. CLOUDS AND LOW LEVEL COLD ADVECTION WILL HOLD
OVERNIGHT LOWS IN THE UPPER 50S NORTH TO MID 60S SOUTH.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
CHALLENGING FORECAST WITH SHALLOW WEDGE SUNDAY ERODING MONDAY AS
LOW LEVEL FLOW VEERS TO SOUTHEAST..AS THE SURFACE RIDGE TO THE
NORTH MOVES OFF THE NEW ENGLAND COAST. TEMPERATURES SUNDAY WILL BE
MUCH COOLER. HAVE INDICATED A CHANCE OF LIGHT RAIN/DRIZZLE WITH
CONTINUED WEAK ISENTROPIC LIFT. COULD SEE ISOLATED THUNDERSTORMS
ACROSS THE CSRA CLOSERS TO THE FRONT. FOR SUNDAY...RANGED HIGH
TEMPERATURES FROM THE UPPER 60S NORTH TO LOWER 80S SOUTH.
OVERNIGHT LOWS IN THE UPPER 50S TO LOWER 60S.
IT APPEARS THE WEDGE WILL ERODE MONDAY AS SOUTHERLY WINDS AT
H850MB INCREASES TO 20 TO 30 KNOTS. KEPT CHANCE OF CONVECTION FOR
MONDAY AS THE ATMOSPHERE BECOMES MODERATELY UNSTABLE. WENT
SLIGHTLY BELOW GUIDANCE CONSENSUS FOR HIGHS IN THE UPPER 70S TO
MID 80S. SHOULD BE MILD MONDAY NIGHT AS THE STRONG COLD FRONT
APPROACHES FROM THE WEST. WIND AND CLOUDS WILL HOLD OVERNIGHT LOWS
IN THE UPPER 60S AND LOWER 70S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AN UPPER RIDGE BUILDS NEAR THE ATLANTIC COAST AND A DEEP TROUGH
DEVELOPS ACROSS THE CENTRAL CONUS CAUSING AN AMPLIFIED UPPER
PATTERN FOR THE LONG TERM. A STRONG COLD FRONT SHOULD CROSS THE
REGION LATE TUESDAY INTO TUESDAY NIGHT AS MIDWEST UPPER TROUGH
MOVES EAST. CONFIDENCE HIGH ENOUGH FOR LIKELY POPS TUESDAY BASED
ON GFS ENSEMBLES. MODERATE TO STRONG INSTABILITY AND MOISTURE
CONVERGENCE AHEAD OF THE FRONT SHOULD BRING SHOWERS AND
THUNDERSTORMS. DEEP LAYER SHEAR SUGGEST SEVERE THUNDERSTORM
POTENTIAL. DRY REST OF PERIOD BEHIND FRONT AS HIGH PRESSURE BUILDS
OVER THE SOUTHEAST. TEMPERATURES SLIGHTLY BELOW NORMAL BEHIND
FRONT.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
A COLD FRONT WILL PUSH SOUTH INTO THE FORECAST AREA THIS AFTERNOON
AND THIS EVENING BRINGING ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS. HAVE NOT INCLUDED ANY RESTRICTIONS DUE TO THUNDERSTORMS
AT THIS TIME DUE TO LOW CONFIDENCE IN TIMING AND COVERAGE.
RESTRICTIONS WILL RETURN OVERNIGHT AS A WEDGE DEVELOPS AND LOW
CLOUDS AND LOWER VSBYS RETURN TO THE AREA. HIGH PRESSURE RIDGES
IN BEHIND THE FRONT AND THE WEDGE BEGINS TO SET UP FOR SUNDAY.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS EXPECTED AS A WEDGE
DEVELOPS EARLY SUNDAY AND PERSISTS INTO MONDAY. RESTRICTIONS ALSO
EXPECTED TUESDAY AFTERNOON THROUGH TUESDAY NIGHT AS A STRONG COLD
FRONT CROSSES THE REGION BRINGING NUMEROUS SHOWERS AND THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
745 AM EDT SAT OCT 11 2014
.SYNOPSIS...
ABOVE NORMAL TEMPERATURES WILL BE FELT ACROSS THE REGION AGAIN TODAY.
THE FRONTAL BOUNDARY WILL SLIP SOUTH ACROSS THE MIDLANDS LATE
THIS AFTERNOON AND TONIGHT. COOL HIGH PRESSURE WILL RIDGE IN FROM THE
NORTH SUNDAY. A STRONG COLD FRONT WILL CROSS THE AREA LATE TUESDAY
AND TUESDAY NIGHT WITH WIDESPREAD SHOWERS AND THUNDERSTORMS. COOL
TEMPERATURES WILL FOLLOW FOR THE END OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
NEARLY ZONAL WESTERLY UPPER LEVEL FLOW ACROSS THE EASTERN PART OF
THE COUNTRY WILL BEGIN TO AMPLIFY TONIGHT AS A POSITIVELY TILTED
TROUGH DIGS INTO THE UPPER MIDWEST. A FRONTAL BOUNDARY EXTENDED
FROM CENTRAL TEXAS NORTHEASTWARD INTO THE TENNESSEE VALLEY TO
SOUTHERN VIRGINIA.
HIGH RESOLUTION HRRR MODEL INDICATES SCATTERED CONVECTION
DEVELOPING ACROSS MIDLANDS THIS MORNING. HOWEVER..LATEST RADAR
IMAGERY INDICATES PRECIPITATION NORTH OF THE AREA FROM NORTHEAST
GA INTO THE UPSTATE OF SC. MESO ANALYSIS SHOWED LIFTED INDICES
AROUND MINUS 3C ACROSS THE CSRA... AND THE RAP AND NAM MODELS
INDICATED THIS AREA OF INSTABILITY TO SPREAD INTO THE MIDLANDS.
WITH THE DEVELOPING CONVECTION INCLUDED A SLIGHT CHANCE FOR THE
CSRA AND MIDLANDS THIS MORNING.
SHOULD SEE PARTLY CLOUDY SKIES DURING MUCH OF THE AFTERNOON.
MODERATE INSTABILITY AND WEAK SHEAR MAY RESULT IN SCATTERED
SHOWERS AND THUNDERSTORMS INTO THE AFTERNOON. KEPT TEMPERATURES IN
THE MID 80S TO AROUND 90...WHICH IS IN LINE WITH GUIDANCE
CONSENSUS.
THE FRONTAL BOUNDARY IS FORECAST TO PUSH SOUTH THROUGH THE MIDLANDS
LATE THIS AFTERNOON AND TONIGHT THEN STALL NEAR OR JUST SOUTH OF
THE CSRA. SURFACE HIGH PRESSURE OVER NEW ENGLAND WILL RIDGE INTO
THE CAROLINAS RESULTING IN A SHALLOW WEDGE/COLD AIR DAMMING
OVERNIGHT. WEAK ISENTROPIC LIFT COULD RESULT IN SPOTTY LIGHT RAIN
AND DRIZZLE TONIGHT. CLOUDS AND LOW LEVEL COLD ADVECTION WILL HOLD
OVERNIGHT LOWS IN THE UPPER 50S NORTH TO MID 60S SOUTH.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
CHALLENGING FORECAST WITH SHALLOW WEDGE SUNDAY ERODING MONDAY AS
LOW LEVEL FLOW VEERS TO SOUTHEAST..AS THE SURFACE RIDGE TO THE
NORTH MOVES OFF THE NEW ENGLAND COAST. TEMPERATURES SUNDAY WILL BE
MUCH COOLER. HAVE INDICATED A CHANCE OF LIGHT RAIN/DRIZZLE WITH
CONTINUED WEAK ISENTROPIC LIFT. COULD SEE ISOLATED THUNDERSTORMS
ACROSS THE CSRA CLOSERS TO THE FRONT. FOR SUNDAY...RANGED HIGH
TEMPERATURES FROM THE UPPER 60S NORTH TO LOWER 80S SOUTH.
OVERNIGHT LOWS IN THE UPPER 50S TO LOWER 60S.
IT APPEARS THE WEDGE WILL ERODE MONDAY AS SOUTHERLY WINDS AT
H850MB INCREASES TO 20 TO 30 KNOTS. KEPT CHANCE OF CONVECTION FOR
MONDAY AS THE ATMOSPHERE BECOMES MODERATELY UNSTABLE. WENT
SLIGHTLY BELOW GUIDANCE CONSENSUS FOR HIGHS IN THE UPPER 70S TO
MID 80S. SHOULD BE MILD MONDAY NIGHT AS THE STRONG COLD FRONT
APPROACHES FROM THE WEST. WIND AND CLOUDS WILL HOLD OVERNIGHT LOWS
IN THE UPPER 60S AND LOWER 70S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AN UPPER RIDGE BUILDS NEAR THE ATLANTIC COAST AND A DEEP TROUGH
DEVELOPS ACROSS THE CENTRAL CONUS CAUSING AN AMPLIFIED UPPER
PATTERN FOR THE LONG TERM. A STRONG COLD FRONT SHOULD CROSS THE
REGION LATE TUESDAY INTO TUESDAY NIGHT AS MIDWEST UPPER TROUGH
MOVES EAST. CONFIDENCE HIGH ENOUGH FOR LIKELY POPS TUESDAY BASED
ON GFS ENSEMBLES. MODERATE TO STRONG INSTABILITY AND MOISTURE
CONVERGENCE AHEAD OF THE FRONT SHOULD BRING SHOWERS AND
THUNDERSTORMS. DEEP LAYER SHEAR SUGGEST SEVERE THUNDERSTORM
POTENTIAL. DRY REST OF PERIOD BEHIND FRONT AS HIGH PRESSURE BUILDS
OVER THE SOUTHEAST. TEMPERATURES SLIGHTLY BELOW NORMAL BEHIND
FRONT.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
LIGHT WINDS AND LOW LEVEL MOISTURE ARE PROMOTING PATCHY STRATUS
AND FOG DEVELOPMENT THIS MORNING. RESTRICTIONS TO CONTINUE THROUGH
DAYBREAK WITH IMPROVEMENT TO VFR EXPECTED AROUND 14/15Z. KOGB
EXPERINCING IFR CONDITIONS WITH VSBYS RISING FROM 1/4SM TO 3/4 SM.
A COLD FRONT WILL PUSH SOUTH ACROSS THE FORECAST AREA THIS
AFTERNOON AND TONIGHT BRINGING ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS. HAVE NOT INCLUDED ANY RESTRICTIONS AT THIS TIME DUE
TO LOW CONFIDENCE IN TIMING AND COVERAGE. RESTRICTIONS WILL RETURN
OVERNIGHT AS A WEDGE DEVELOPS AND LOW CLOUDS RETURN TO THE AREA.
WINDS WILL REMAIN OUT OF THE SOUTH- SOUTHWEST THIS MORNING AND
VEER TO WESTERLY BY 21Z AND VEER TO NORTH/NORTHEASTERLY TOWARD THE
END OF THE TAF PERIOD AS HIGH PRESSURE RIDGES IN BEHIND THE FRONT
AND THE WEDGE BEGINS TO SET UP.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS EXPECTED AS A WEDGE
DEVELOPS EARLY SUNDAY AND PERSISTS INTO MONDAY. RESTRICTIONS ALSO
EXPECTED TUESDAY AFTERNOON THROUGH TUESDAY NIGHT AS A STRONG COLD
FRONT CROSSES THE REGION BRINGING NUMEROUS SHOWERS AND THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
507 AM EDT SAT OCT 11 2014
.SYNOPSIS...
ABOVE NORMAL TEMPERATURES WILL BE FELT ACROSS THE REGION AGAIN TODAY.
THE FRONTAL BOUNDARY WILL SLIP SOUTH ACROSS THE MIDLANDS LATE
THIS AFTERNOON AND TONIGHT. COOL HIGH PRESSURE WILL RIDGE IN FROM THE
NORTH SUNDAY. A STRONG COLD FRONT WILL CROSS THE AREA LATE TUESDAY
AND TUESDAY NIGHT WITH WIDESPREAD SHOWERS AND THUNDERSTORMS. COOL
TEMPERATURES WILL FOLLOW FOR THE END OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
NEARLY ZONAL WESTERLY UPPER LEVEL FLOW ACROSS THE EASTERN PART OF
THE COUNTRY WILL BEGIN TO AMPLIFY TONIGHT AS A POSITIVELY TILTED
TROUGH DIGS INTO THE UPPER MIDWEST. A FRONTAL BOUNDARY EXTENDED
FROM CENTRAL TEXAS NORTHEASTWARD INTO THE TENNESSEE VALLEY TO
SOUTHERN VIRGINIA.
HIGH RESOLUTION HRRR MODEL INDICATED SCATTERED CONVECTION
DEVELOPING ACROSS THE CSRA TO THE CENTRAL MIDLANDS AROUND SUNRISE.
MESO ANALYSIS SHOWED LIFTED INDICES AROUND MINUS 3C ACROSS THE
CSRA... AND THE RAP AND NAM MODELS INDICATED THIS AREA OF
INSTABILITY TO SPREAD NORTHWARD INTO THE MIDLANDS. THEREFORE WE
INCLUDED A CHANCE FOR CONVECTION FOR THIS MORNING.
SHOULD SEE PARTLY CLOUDY SKIES DURING MUCH OF THE AFTERNOON.
MODERATE INSTABILITY AND WEAK SHEAR MAY RESULT IN SCATTERED
SHOWERS AND THUNDERSTORMS INTO THE AFTERNOON. KEPT TEMPERATURES IN
THE MID 80S TO AROUND 90...WHICH IS IN LINE WITH GUIDANCE
CONSENSUS.
THE FRONTAL BOUNDARY IS FORECAST TO PUSH SOUTH THROUGH THE MIDLANDS
LATE THIS AFTERNOON AND TONIGHT THEN STALL NEAR OR JUST SOUTH OF
THE CSRA. SURFACE HIGH PRESSURE OVER NEW ENGLAND WILL RIDGE INTO
THE CAROLINAS RESULTING IN A SHALLOW WEDGE/COLD AIR DAMMING
OVERNIGHT. WEAK ISENTROPIC LIFT COULD RESULT IN SPOTTY LIGHT RAIN
AND DRIZZLE TONIGHT. CLOUDS AND LOW LEVEL COLD ADVECTION WILL HOLD
OVERNIGHT LOWS IN THE UPPER 50S NORTH TO MID 60S SOUTH.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
CHALLENGING FORECAST WITH SHALLOW WEDGE SUNDAY ERODING MONDAY AS
LOW LEVEL FLOW VEERS TO SOUTHEAST..AS THE SURFACE RIDGE TO THE
NORTH MOVES OFF THE NEW ENGLAND COAST. TEMPERATURES SUNDAY WILL BE
MUCH COOLER. HAVE INDICATED A CHANCE OF LIGHT RAIN/DRIZZLE WITH
CONTINUED WEAK ISENTROPIC LIFT. COULD SEE ISOLATED THUNDERSTORMS
ACROSS THE CSRA CLOSERS TO THE FRONT. FOR SUNDAY...RANGED HIGH
TEMPERATURES FROM THE UPPER 60S NORTH TO LOWER 80S SOUTH.
OVERNIGHT LOWS IN THE UPPER 50S TO LOWER 60S.
IT APPEARS THE WEDGE WILL ERODE MONDAY AS SOUTHERLY WINDS AT
H850MB INCREASES TO 20 TO 30 KNOTS. KEPT CHANCE OF CONVECTION FOR
MONDAY AS THE ATMOSPHERE BECOMES MODERATELY UNSTABLE. WENT
SLIGHTLY BELOW GUIDANCE CONSENSUS FOR HIGHS IN THE UPPER 70S TO
MID 80S. SHOULD BE MILD MONDAY NIGHT AS THE STRONG COLD FRONT
APPROACHES FROM THE WEST. WIND AND CLOUDS WILL HOLD OVERNIGHT LOWS
IN THE UPPER 60S AND LOWER 70S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AN UPPER RIDGE BUILDS NEAR THE ATLANTIC COAST AND A DEEP TROUGH
DEVELOPS ACROSS THE CENTRAL CONUS CAUSING AN AMPLIFIED UPPER
PATTERN FOR THE LONG TERM. A STRONG COLD FRONT SHOULD CROSS THE
REGION LATE TUESDAY INTO TUESDAY NIGHT AS MIDWEST UPPER TROUGH
MOVES EAST. CONFIDENCE HIGH ENOUGH FOR LIKELY POPS TUESDAY BASED
ON GFS ENSEMBLES. MODERATE TO STRONG INSTABILITY AND MOISTURE
CONVERGENCE AHEAD OF THE FRONT SHOULD BRING SHOWERS AND
THUNDERSTORMS. DEEP LAYER SHEAR SUGGEST SEVERE THUNDERSTORM
POTENTIAL. DRY REST OF PERIOD BEHIND FRONT AS HIGH PRESSURE BUILDS
OVER THE SOUTHEAST. TEMPERATURES SLIGHTLY BELOW NORMAL BEHIND
FRONT.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
LIGHT WINDS AND LOW LEVEL MOISTURE ARE PROMOTING PATCHY STRATUS
AND FOG DEVELOPMENT THIS MORNING. RESTRICTIONS TO CONTINUE THROUGH
DAYBREAK WITH IMPROVEMENT TO VFR EXPECTED AROUND 14/15Z. A COLD
FRONT WILL PUSH SOUTH ACROSS THE FORECAST AREA THIS AFTERNOON AND
TONIGHT BRINGING ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS.
HAVE NOT INCLUDED ANY RESTRICTIONS AT THIS TIME DUE TO LOW
CONFIDENCE IN TIMING AND COVERAGE. RESTRICTIONS WILL RETURN
OVERNIGHT AS A WEDGE DEVELOPS AND LOW CLOUDS RETURN TO THE AREA.
WINDS WILL REMAIN OUT OF THE SOUTH-SOUTHWEST THIS MORNING AND
VEER TO WESTERLY BY 21Z AND VEER TO NORTH/NORTHEASTERLY TOWARD THE
END OF THE TAF PERIOD AS HIGH PRESSURE RIDGES IN BEHIND THE FRONT
AND THE WEDGE BEGINS TO SET UP.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS EXPECTED AS A WEDGE
DEVELOPS EARLY SUNDAY AND PERSISTS INTO MONDAY. RESTRICTIONS ALSO
EXPECTED TUESDAY AFTERNOON THROUGH TUESDAY NIGHT AS A STRONG COLD
FRONT CROSSES THE REGION BRINGING NUMEROUS SHOWERS AND THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
427 AM EDT SAT OCT 11 2014
.SYNOPSIS...
ABOVE NORMAL TEMPERATURES WILL BE FELT ACROSS THE REGION AGAIN TODAY.
THE FRONTAL BOUNDARY WILL SLIP SOUTH ACROSS THE MIDLANDS LATE
THIS AFTERNOON AND TONIGHT. COOL HIGH PRESSURE WILL RIDGE IN FROM THE
NORTH SUNDAY. A STRONG COLD FRONT WILL CROSS THE AREA LATE TUESDAY
AND TUESDAY NIGHT WITH WIDESPREAD SHOWERS AND THUNDERSTORMS. COOL
TEMPERATURES WILL FOLLOW FOR THE END OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
NEARLY ZONAL WESTERLY UPPER LEVEL FLOW ACROSS THE EASTERN PART OF
THE COUNTRY WILL BEGIN TO AMPLIFY TONIGHT AS A POSITIVELY TILTED
TROUGH DIGS INTO THE UPPER MIDWEST. A FRONTAL BOUNDARY EXTENDED
FROM CENTRAL TEXAS NORTHEASTWARD INTO THE TENNESSEE VALLEY TO
SOUTHERN VIRGINIA.
HIGH RESOLUTION HRRR MODEL INDICATED SCATTERED CONVECTION
DEVELOPING ACROSS THE CSRA TO THE CENTRAL MIDLANDS AROUND SUNRISE.
MESO ANALYSIS SHOWED LIFTED INDICES AROUND MINUS 3C ACROSS THE
CSRA... AND THE RAP AND NAM MODELS INDICATED THIS AREA OF
INSTABILITY TO SPREAD NORTHWARD INTO THE MIDLANDS. THEREFORE WE
INCLUDED A CHANCE FOR CONVECTION FOR THIS MORNING.
SHOULD SEE PARTLY CLOUDY SKIES DURING MUCH OF THE AFTERNOON.
MODERATE INSTABILITY AND WEAK SHEAR MAY RESULT IN SCATTERED
SHOWERS AND THUNDERSTORMS INTO THE AFTERNOON. KEPT TEMPERATURES IN
THE MID 80S TO AROUND 90...WHICH IS IN LINE WITH GUIDANCE
CONSENSUS.
THE FRONTAL BOUNDARY IS FORECAST TO PUSH SOUTH THROUGH THE MIDLANDS
LATE THIS AFTERNOON AND TONIGHT THEN STALL NEAR OR JUST SOUTH OF
THE CSRA. SURFACE HIGH PRESSURE OVER NEW ENGLAND WILL RIDGE INTO
THE CAROLINAS RESULTING IN A SHALLOW WEDGE/COLD AIR DAMMING
OVERNIGHT. WEAK ISENTROPIC LIFT COULD RESULT IN SPOTTY LIGHT RAIN
AND DRIZZLE TONIGHT. CLOUDS AND LOW LEVEL COLD ADVECTION WILL HOLD
OVERNIGHT LOWS IN THE UPPER 50S NORTH TO MID 60S SOUTH.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
CHALLENGING FORECAST WITH SHALLOW WEDGE SUNDAY ERODING MONDAY AS
LOW LEVEL FLOW VEERS TO SOUTHEAST..AS THE SURFACE RIDGE TO THE
NORTH MOVES OFF THE NEW ENGLAND COAST. TEMPERATURES SUNDAY WILL BE
MUCH COOLER. HAVE INDICATED A CHANCE OF LIGHT RAIN/DRIZZLE WITH
CONTINUED WEAK ISENTROPIC LIFT. COULD SEE ISOLATED THUNDERSTORMS
ACROSS THE CSRA CLOSERS TO THE FRONT. FOR SUNDAY...RANGED HIGH
TEMPERATURES FROM THE UPPER 60S NORTH TO LOWER 80S SOUTH.
OVERNIGHT LOWS IN THE UPPER 50S TO LOWER 60S.
IT APPEARS THE WEDGE WILL ERODE MONDAY AS SOUTHERLY WINDS AT
H850MB INCREASES TO 20 TO 30 KNOTS. KEPT CHANCE OF CONVECTION FOR
MONDAY AS THE ATMOSPHERE BECOMES MODERATELY UNSTABLE. WENT
SLIGHTLY BELOW GUIDANCE CONSENSUS FOR HIGHS IN THE UPPER 70S TO
MID 80S. SHOULD BE MILD MONDAY NIGHT AS THE STRONG COLD FRONT
APPROACHES FROM THE WEST. WIND AND CLOUDS WILL HOLD OVERNIGHT LOWS
IN THE UPPER 60S AND LOWER 70S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AN UPPER RIDGE BUILDS NEAR THE ATLANTIC COAST AND A DEEP TROUGH
DEVELOPS ACROSS THE CENTRAL CONUS CAUSING AN AMPLIFIED UPPER
PATTERN FOR THE LONG TERM. A STRONG COLD FRONT SHOULD CROSS THE
REGION LATE TUESDAY INTO TUESDAY NIGHT AS MIDWEST UPPER TROUGH
MOVES EAST. CONFIDENCE HIGH ENOUGH FOR LIKELY POPS TUESDAY BASED
ON GFS ENSEMBLES. MODERATE TO STRONG INSTABILITY AND MOISTURE
CONVERGENCE AHEAD OF THE FRONT SHOULD BRING SHOWERS AND
THUNDERSTORMS. DEEP LAYER SHEAR SUGGEST SEVERE THUNDERSTORM
POTENTIAL. DRY REST OF PERIOD BEHIND FRONT AS HIGH PRESSURE BUILDS
OVER THE SOUTHEAST. TEMPERATURES SLIGHTLY BELOW NORMAL BEHIND
FRONT.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS EXPECTED TO PREVAIL FOR A MAJORITY OF THE TAF
PERIOD. MODELS SUGGEST SOME STRATUS OR PATCHY FOG DEVELOPING
TOWARD DAYBREAK...WILL DEPEND ON THE STRENGTH OF THE LOW-LEVEL JET
THAT NAM BUFKIT IS SHOWING OVERNIGHT. HAVE CONTINUED TO
INDICATE MVFR AT FOG PRONE AGS/OGB AND CONDITIONS RETURNING TO VFR
BY 14Z. A COLD FRONT WILL PUSH SOUTH ACROSS THE FORECAST AREA THIS
AFTERNOON AND EVENING ALTHOUGH THE BEST CHANCES FOR SHOWERS AND
STORMS WILL REMAIN NORTH OF THE TERMINALS SO HAVE NOT INCLUDED ANY
RESTRICTIONS AT THIS TIME. WINDS WILL REMAIN OUT OF THE SOUTH-
SOUTHWEST THIS MORNING AND VEER TO WESTERLY BY 21Z AND VEER TO
NORTH/NORTHEASTERLY TOWARD THE END OF THE TAF PERIOD AS HIGH
PRESSURE RIDGES IN BEHIND THE FRONT AND A WEDGE BEGINS TO SET UP.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS EXPECTED AS A WEDGE
DEVELOPS EARLY SUNDAY AND PERSISTS INTO MONDAY. RESTRICTIONS ALSO
EXPECTED TUESDAY AFTERNOON THROUGH TUESDAY NIGHT AS A STRONG COLD
FRONT CROSSES THE REGION BRINGING NUMEROUS SHOWERS AND THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
214 AM EDT SAT OCT 11 2014
.SYNOPSIS...
ABOVE NORMAL TEMPERATURES WILL REMAIN ACROSS AREA TODAY AS A COLD
FRONT DEVELOPS NORTH OF THE REGION. THE FRONTAL BOUNDARY WILL SLIP
SOUTH ACROSS THE MIDLANDS LATE THIS AFTERNOON. COOL HIGH PRESSURE
WILL RIDGE IN FROM THE NORTH SUNDAY. A STRONG COLD FRONT IS
EXPECTED TO CROSS THE AREA LATE TUESDAY AND TUESDAY NIGHT WITH
NUMEROUS THUNDERSTORMS. COOL TEMPERATURES WILL FOLLOW FOR THE END
OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
NEARLY ZONAL WESTERLY UPPER LEVEL FLOW ACROSS THE EASTERN PART OF
THE COUNTRY WITH A POSITIVELY TILTED TROUGH DIGGING INTO THE UPPER
MIDWEST WITH AN UPPER RIDGE OVER THE GULF OF MEXICO NOSING INTO
THE GULF COAST STATES. A FRONTAL BOUNDARY EXTENDED FROM CENTRAL
TEXAS NORTHEASTWARD INTO THE TENNESSEE VALLEY TO EASTERN WEST
VIRGINIA.
AS THE FRONTAL BOUNDARY SINKS SOUTHWARD OVERNIGHT THE POSSIBILITY
OF NOCTURNAL PRECIPITATION WILL BECOME FOCUSED ACROSS THE NORTHERN
AND WESTERN MIDLANDS...THOUGH MOISTURE IS LIMITED WITH PWAT VALUES
ONLY AROUND 1.3 INCHES. HIGH RESOLUTION HRRR DOES NOT INDICATE ANY
ADDITIONAL CONVECTION OVERNIGHT BUT WILL CONTINUE TO HOLD ON TO
SLIGHT CHANCE TO CHANCE POPS DURING THE PREDAWN HOURS WITH
FAVORABLE CORFIDI VECTORS AND UPSTREAM CONVECTION EXPECTED TO PUSH
EASTWARD.
SHOULD SEE SOME INCREASE IN HIGH AND MID LEVEL CLOUDS OVERNIGHT.
LOW TEMPERATURES WILL BE IN THE MID AND UPPER 60S WITH SOME
POSSIBLE STRATUS OR PATCHY FOG TOWARD MORNING.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH SUNDAY NIGHT/...
THE FRONTAL BOUNDARY IS FORECAST TO PUSH SOUTH ACROSS THE MIDLANDS
SATURDAY AFTERNOON AND SATURDAY NIGHT AND STALL NEAR OR JUST SOUTH
OF THE CSRA. SURFACE HIGH PRESSURE OVER NEW ENGLAND WILL RIDGE
INTO THE CAROLINAS RESULTING IN A SHALLOW WEDGE/COLD AIR DAMMING
SATURDAY NIGHT INTO SUNDAY NIGHT.
MOST OF THE SHOWERS SHOULD REMAIN NEAR THE FRONT ON SATURDAY...SO
KEPT CHANCE POPS ACROSS THE NORTHERN AND CENTRAL MIDLANDS. GIVEN
WEST-SOUTHWEST 850MB FLOW...TEMPERATURES WILL BE STILL BE WARM ON
SATURDAY WITH HIGHS RANGING FROM THE LOWER 80S NORTH TO NEAR 90
SOUTH. OVERNIGHT LOWS IN THE LOW TO MID 60S.
WITH SHALLOW WEDGE/COLD AIR DAMMING ON SUNDAY SHOULD SEE COOLER
TEMPERATURES AND A CHANCE OF LIGHT RAIN. COULD SEE ISOLATED
THUNDERSTORMS ACROSS THE CSRA CLOSERS TO THE FRONT. RANGED HIGH
TEMPERATURES FROM THE UPPER 60S NORTH TO MID 80S SOUTH. OVERNIGHT
LOWS IN THE LOW TO MID 60S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
RIDGE BUILDS NEAR THE ATLANTIC COAST AND A DEEP TROUGH DEVELOPS
ACROSS THE CENTRAL CONUS CAUSING AN AMPLIFIED UPPER PATTERN. THE
GFS AND ECMWF CONTINUE TO CONVERGE.
CHALLENGING FORECAST WITH SHALLOW WEDGE FROM SUNDAY ERODING
MONDAY AS LOW LEVEL FLOW VEERS TO SOUTHEAST AS SURFACE RIDGE TO
THE NORTH MOVES OFF THE NEW ENGLAND COAST. UPPER RIDGE BUILDING
OFF CAROLINA COAST IN RESPONSE TO DEEP TROUGH MOVING ACROSS
PLAINS. A STRONG COLD FRONT SHOULD CROSS THE REGION LATE TUESDAY
INTO TUESDAY NIGHT AS MIDWEST UPPER TROUGH MOVES EAST. CONFIDENCE
HIGH ENOUGH FOR LIKELY POPS TUESDAY BASED ON GFS ENSEMBLES.
MODERATE TO STRONG INSTABILITY AND MOISTURE CONVERGENCE AHEAD OF
THE FRONT SHOULD BRING SHOWERS AND THUNDERSTORMS. DEEP LAYER SHEAR
SUGGEST SEVERE THUNDERSTORM POTENTIAL. DRY REST OF PERIOD BEHIND
FRONT AS HIGH PRESSURE BUILDS OVER THE SOUTHEAST. TEMPERATURES
SLIGHTLY BELOW NORMAL BEHIND FRONT.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS EXPECTED TO PREVAIL FOR A MAJORITY OF THE TAF
PERIOD. MODELS SUGGEST SOME STRATUS OR PATCHY FOG DEVELOPING
TOWARD DAYBREAK...WILL DEPEND ON THE STRENGTH OF THE LOW-LEVEL JET
THAT NAM BUFKIT IS SHOWING OVERNIGHT. HAVE CONTINUED TO
INDICATE MVFR AT FOG PRONE AGS/OGB AND CONDITIONS RETURNING TO VFR
BY 14Z. A COLD FRONT WILL PUSH SOUTH ACROSS THE FORECAST AREA THIS
AFTERNOON AND EVENING ALTHOUGH THE BEST CHANCES FOR SHOWERS AND
STORMS WILL REMAIN NORTH OF THE TERMINALS SO HAVE NOT INCLUDED ANY
RESTRICTIONS AT THIS TIME. WINDS WILL REMAIN OUT OF THE SOUTH-
SOUTHWEST THIS MORNING AND VEER TO WESTERLY BY 21Z AND VEER TO
NORTH/NORTHEASTERLY TOWARD THE END OF THE TAF PERIOD AS HIGH
PRESSURE RIDGES IN BEHIND THE FRONT AND A WEDGE BEGINS TO SET UP.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS EXPECTED AS A WEDGE
DEVELOPS EARLY SUNDAY AND PERSISTS INTO MONDAY. RESTRICTIONS ALSO
EXPECTED TUESDAY AFTERNOON THROUGH TUESDAY NIGHT AS A STRONG COLD
FRONT CROSSES THE REGION BRINGING NUMEROUS SHOWERS AND THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
129 PM EDT Sat Oct 11 2014
...Updated Aviation Discussion...
...Forecast Update...
Issued at 905 AM EDT Sat Oct 11 2014
Removed thunder wording from across our south. Latest high-res
guidance indicates little to no lightning potential down there.
Given fairly uniform temperatures north to south and cloud cover,
think it`s a good bet not to get any thunder today. Sharp pop
gradient across the region still looks good. Only other addition was
a layer in between where we may see some scattered sprinkles, still
mainly south of the I-64 corridor. Latest HRRR seems too far north
with its rain shield, but would not be surprised to see some
sprinkles edge in this afternoon.
.SHORT TERM (Now through Sunday)...
Issued at 303 AM EDT Sat Oct 11 2014
The cold front that moved through the area yesterday will continue
to slowly sink to the south and east this morning. This boundary
will eventually stall out across TN. Aloft a shortwave will approach
the area today.
Most of the showers have moved east of the region early this
morning. Some patchy drizzle will be possible, but most areas will
be dry. As the upper level disturbance nears, showers and possibly a
few thunderstorms will develop and move into south central Kentucky.
Have lowered pops across the northern half of the forecast area
considerably and taken them out all together in places. Models all
suggest that precip will remain closer to the surface boundary
today. Will continue to mention scattered precipitation overnight.
For Sunday the boundary will begin to lift back to the north as a
warm front. With this moisture will be on the increase as will
showers and thunderstorms. Have kept pops lower in southern Indiana
as the front may not make it that far north during the day.
Temperatures today will remain on the cool side with highs topping
out in the lower 60s. Lows tonight will range from the upper 40s to
mid 50s. Sunday will be quite a bit warmer in many places with the
warm front lifting north across the region. Highs will range from
the upper 60s in the north to the mid 70s in the south.
.LONG TERM (Sunday night through Friday)...
Issued at 350 AM EDT Sat Oct 11 2014
...Strong Thunderstorms and Heavy Rainfall Likely Monday Night Into
Tuesday Morning...
The long term period will start out with a broad southwesterly flow
at the surface and aloft. While a mid-level wave will be exiting
the area, the multi-model consensus is in agreement with the
nocturnal low-level jet kicking up. This feature combined with
low-level moisture transport and some elevated instability as noted
by model proximity soundings should support a continued convective
threat during the overnight hours. Coverage is likely to be in on
the high end of the chance range...perhaps even rising to the likely
range. The increase in moisture transport will result in heavier
rainfall potential...with some storms possibly producing torrential
rainfall at times.
Convective activity will likely diminish in coverage Monday morning
as the low-level jet retrogrades west and away from the region.
Southerly level low flow will increase moderately throughout the
day. We expect to be deep in the warm sector throughout the day as
temperatures are likely to warm into the upper 70s. Some breaks in
the cloud cover may occur, and if so, then will push our maximum
temps into the lower 80s. Within the broad warm air advection
scheme, we`ll likely see instability develop during the afternoon
hours. Overall, the instability will likely be conditional on the
amount of insolation we receive throughout the day. Nonetheless, we
should see at least some isolated-scattered convection developing
during the afternoon/eve hours.
Monday night still looks to be the main time for strong/severe
convection across the region. Strong synoptic scale ascent,
courtesy of large H5 height falls with an approaching front,
combined with an increasing low-level jet should result in a rather
extensive squall line developing to the west of the Ohio Valley.
The multi-model consensus continues to be in good agreement with
40-55kts of bulk shear, with a low-level jet axis of 50-65kts
impinging into the Ohio Valley late Monday night. Current thinking
is that the large squall line out to the west will slide eastward
into our region late Monday night and early Tuesday morning. Given
that the line will be moving in as instability drops, due to
nocturnal cooling/loss of insolation, strong dynamical forcing will
likely keep storms at strong to severe levels. CIPS analog guidance
suggests that a decent severe weather risk will be possible across
the region...though the highest threat will likely remain to our
west and southwest. Torrential rainfall and damaging winds look to
be the main severe weather hazards. However, the quasi-linear
squall line will likely have embedded bowing line segments that
could result in some isolated tornadoes. Obviously something to
watch over the next few days.
Surface cold front should push through the region on Tuesday
bringing the threat of heavy rainfall to a gradual end by Tuesday
evening. Temperatures Tuesday will likely have early morning highs
with temperatures falling a bit during the day. Highs will range
from the lower 60s in the north to the mid 60s down south. Lows
Tuesday night should cool down into the upper 40s.
For Wednesday and beyond, there continues to be a rather large
spread in the guidance on how the upper level flow will evolve. The
GFS and GEM runs are more progressive with the upper level flow
while the Euro has continued the idea of a massive cut off low
developing over the eastern US. By all accounts the Euro solution
remains an outlier, but in comparison, much of the other guidance is
gradually slowing down aloft during the period. Given the usual
superiority of the Euro in the long term, its hard to ignore the
last several runs suggesting this cut off low. For now, have
trended the forecast toward this idea, but have not completely
discounted the progressive GFS/GEM runs. We`ll keep some diurnally
driven showers in the forecast for Wed-Fri since we`ll probably be
under the cut off. Clouds associated with the cut off will likely
keep our temperatures down. Thus, have trimmed back highs on the
SuperBlend guidance and gone with lower-mid 60s for highs and
overnight lows in the 40s.
&&
.HYDROLOGY...
Issued at 350 AM EDT Sat Oct 11 2014
From a hydrologic standpoint, expect highest rainfall amounts today
and tonight to be mainly across southern Kentucky which will be
closer to the surface frontal boundary. This boundary will lift
northward on Sunday bringing better chances of precipitation to the
region. While widespread heavy rain is not expected, but where
storms do occur, high rainfall rates could cause ponding of water
and could result in area creeks and streams filling up rather
quickly.
More heavy rainfall...and perhaps more widespread...will occur late
Monday and into Tuesday as a strong upper trough and surface cold
front move through the region. The exact evolution of this system
will determine whether 1) copious rain amounts fall over KY and
southern IN, or 2) whether rainfall is heavy but progressive, or 3)
whether the heaviest rain and strongest (possibly severe) storms
remain more across TN and the northern Gulf states. Either of the
last two scenarios described above looks like the best bet right
now. Nevertheless, periods of heavy rain should fall Monday night,
with rain diminishing in intensity on Tuesday.
General rainfall amounts could vary widely across central KY and
southern IN through Tuesday morning depending on storm coverage and
propagation. Nevertheless, with high atmospheric moisture content,
most storms should produce brief heavy rain. Total accumulated
rainfall amounts of 2 to 4 inches, possibly isolated higher
especially in southern KY, could occur by Tuesday morning. Depending
on how storms evolve over the next few days, a Flood or Flash Flood
Watch may be required in later forecasts.
&&
.AVIATION (18Z TAF Update)...
Issued at 125 PM EDT Sat Oct 11 2014
Poor ceilings continue at KBWG, but are showing signs of rising
slowly. Still expect some light rain showers down there, and they
may help to scour things enough to get cigs back into the MVFR range
in a few hours. At rest of sites models are showing some low-level
subsidence that combined with some drying should erode the MVFR cigs
some. Expect poor conditions to return overnight at least to
LEX/BWG, and perhaps to SDF by daybreak as the front over Tennessee
starts lifting northward as a warm front. This will bring a better
shot at showers during the day Sunday. Cannot rule out thunder late
in the SDF period, but too early to throw in just yet.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........RJS
Short Term.....EER
Long Term......MJ
Hydrology......MJ/EER
Aviation.......RJS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
909 AM EDT Sat Oct 11 2014
...Forecast Update...
Issued at 905 AM EDT Sat Oct 11 2014
Removed thunder wording from across our south. Latest high-res
guidance indicates little to no lightning potential down there.
Given fairly uniform temperatures north to south and cloud cover,
think it`s a good bet not to get any thunder today. Sharp pop
gradient across the region still looks good. Only other addition was
a layer in between where we may see some scattered sprinkles, still
mainly south of the I-64 corridor. Latest HRRR seems too far north
with its rain shield, but would not be surprised to see some
sprinkles edge in this afternoon.
.SHORT TERM (Now through Sunday)...
Issued at 303 AM EDT Sat Oct 11 2014
The cold front that moved through the area yesterday will continue
to slowly sink to the south and east this morning. This boundary
will eventually stall out across TN. Aloft a shortwave will approach
the area today.
Most of the showers have moved east of the region early this
morning. Some patchy drizzle will be possible, but most areas will
be dry. As the upper level disturbance nears, showers and possibly a
few thunderstorms will develop and move into south central Kentucky.
Have lowered pops across the northern half of the forecast area
considerably and taken them out all together in places. Models all
suggest that precip will remain closer to the surface boundary
today. Will continue to mention scattered precipitation overnight.
For Sunday the boundary will begin to lift back to the north as a
warm front. With this moisture will be on the increase as will
showers and thunderstorms. Have kept pops lower in southern Indiana
as the front may not make it that far north during the day.
Temperatures today will remain on the cool side with highs topping
out in the lower 60s. Lows tonight will range from the upper 40s to
mid 50s. Sunday will be quite a bit warmer in many places with the
warm front lifting north across the region. Highs will range from
the upper 60s in the north to the mid 70s in the south.
.LONG TERM (Sunday night through Friday)...
Issued at 350 AM EDT Sat Oct 11 2014
...Strong Thunderstorms and Heavy Rainfall Likely Monday Night Into
Tuesday Morning...
The long term period will start out with a broad southwesterly flow
at the surface and aloft. While a mid-level wave will be exiting
the area, the multi-model consensus is in agreement with the
nocturnal low-level jet kicking up. This feature combined with
low-level moisture transport and some elevated instability as noted
by model proximity soundings should support a continued convective
threat during the overnight hours. Coverage is likely to be in on
the high end of the chance range...perhaps even rising to the likely
range. The increase in moisture transport will result in heavier
rainfall potential...with some storms possibly producing torrential
rainfall at times.
Convective activity will likely diminish in coverage Monday morning
as the low-level jet retrogrades west and away from the region.
Southerly level low flow will increase moderately throughout the
day. We expect to be deep in the warm sector throughout the day as
temperatures are likely to warm into the upper 70s. Some breaks in
the cloud cover may occur, and if so, then will push our maximum
temps into the lower 80s. Within the broad warm air advection
scheme, we`ll likely see instability develop during the afternoon
hours. Overall, the instability will likely be conditional on the
amount of insolation we receive throughout the day. Nonetheless, we
should see at least some isolated-scattered convection developing
during the afternoon/eve hours.
Monday night still looks to be the main time for strong/severe
convection across the region. Strong synoptic scale ascent,
courtesy of large H5 height falls with an approaching front,
combined with an increasing low-level jet should result in a rather
extensive squall line developing to the west of the Ohio Valley.
The multi-model consensus continues to be in good agreement with
40-55kts of bulk shear, with a low-level jet axis of 50-65kts
impinging into the Ohio Valley late Monday night. Current thinking
is that the large squall line out to the west will slide eastward
into our region late Monday night and early Tuesday morning. Given
that the line will be moving in as instability drops, due to
nocturnal cooling/loss of insolation, strong dynamical forcing will
likely keep storms at strong to severe levels. CIPS analog guidance
suggests that a decent severe weather risk will be possible across
the region...though the highest threat will likely remain to our
west and southwest. Torrential rainfall and damaging winds look to
be the main severe weather hazards. However, the quasi-linear
squall line will likely have embedded bowing line segments that
could result in some isolated tornadoes. Obviously something to
watch over the next few days.
Surface cold front should push through the region on Tuesday
bringing the threat of heavy rainfall to a gradual end by Tuesday
evening. Temperatures Tuesday will likely have early morning highs
with temperatures falling a bit during the day. Highs will range
from the lower 60s in the north to the mid 60s down south. Lows
Tuesday night should cool down into the upper 40s.
For Wednesday and beyond, there continues to be a rather large
spread in the guidance on how the upper level flow will evolve. The
GFS and GEM runs are more progressive with the upper level flow
while the Euro has continued the idea of a massive cut off low
developing over the eastern US. By all accounts the Euro solution
remains an outlier, but in comparison, much of the other guidance is
gradually slowing down aloft during the period. Given the usual
superiority of the Euro in the long term, its hard to ignore the
last several runs suggesting this cut off low. For now, have
trended the forecast toward this idea, but have not completely
discounted the progressive GFS/GEM runs. We`ll keep some diurnally
driven showers in the forecast for Wed-Fri since we`ll probably be
under the cut off. Clouds associated with the cut off will likely
keep our temperatures down. Thus, have trimmed back highs on the
SuperBlend guidance and gone with lower-mid 60s for highs and
overnight lows in the 40s.
&&
.HYDROLOGY...
Issued at 350 AM EDT Sat Oct 11 2014
From a hydrologic standpoint, expect highest rainfall amounts today
and tonight to be mainly across southern Kentucky which will be
closer to the surface frontal boundary. This boundary will lift
northward on Sunday bringing better chances of precipitation to the
region. While widespread heavy rain is not expected, but where
storms do occur, high rainfall rates could cause ponding of water
and could result in area creeks and streams filling up rather
quickly.
More heavy rainfall...and perhaps more widespread...will occur late
Monday and into Tuesday as a strong upper trough and surface cold
front move through the region. The exact evolution of this system
will determine whether 1) copious rain amounts fall over KY and
southern IN, or 2) whether rainfall is heavy but progressive, or 3)
whether the heaviest rain and strongest (possibly severe) storms
remain more across TN and the northern Gulf states. Either of the
last two scenarios described above looks like the best bet right
now. Nevertheless, periods of heavy rain should fall Monday night,
with rain diminishing in intensity on Tuesday.
General rainfall amounts could vary widely across central KY and
southern IN through Tuesday morning depending on storm coverage and
propagation. Nevertheless, with high atmospheric moisture content,
most storms should produce brief heavy rain. Total accumulated
rainfall amounts of 2 to 4 inches, possibly isolated higher
especially in southern KY, could occur by Tuesday morning. Depending
on how storms evolve over the next few days, a Flood or Flash Flood
Watch may be required in later forecasts.
&&
.AVIATION (12Z TAF Update)...
Issued at 630 AM EDT Sat Oct 11 2014
Low ceilings will continue to be the main issue for this TAF period.
Ceilings at SDF have risen to MVFR this morning and LEX is currently
IFR. Drier air will be moving in today across north central KY with
an area of high pressure. Thus, ceilings are expected to improve
slowly at these two sites through the morning and they will become
VFR this afternoon. Winds will remain out of the northeast today
around 7-9 knots.
Low level moisture will keep cigs lower at BWG thanks to its
proximity to a stalled frontal boundary. Conditions will improve
somewhat but cigs are expected to remain MVFR through the day. In
addition showers will move into the area and across the airport at
times.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........RJS
Short Term.....EER
Long Term......MJ
Hydrology......MJ/EER
Aviation.......EER
AREA FORECAST DISCUSSION
NWS JACKSON KY
115 AM EDT SAT OCT 11 2014
.UPDATE...
ISSUED AT 115 AM EDT SAT OCT 11 2014
BACK EDGE OF RAIN SHOWERS IS PUSHING ACROSS CENTRAL KENTUCKY AND
SHOULD WORK INTO AND ACROSS EASTERN KENTUCKY OVER THE NEXT 4 TO 6
HOURS. THIS WILL GRADUALLY BRING AN END TO THE RAIN FROM WEST TO EAST
BY DAYBREAK. A FEW SHOWERS MAY LINGER JUST PAST DAYBREAK IN THE
EAST...BUT FOR THE MOST PART...THINGS SHOULD BE WINDING DOWN.
ADJUSTED POPS TO REFLECT THESE TRENDS. OTHERWISE...TEMPERATURES AND
DEWPOINTS ARE ON TRACK...SO NO OTHER CHANGES NEEDED AT THIS TIME.
UPDATE ISSUED AT 1101 PM EDT FRI OCT 10 2014
RAIN CONTINUES TO PUSH ACROSS EASTERN KENTUCKY. BEST COVERAGE REMAINS
ACROSS THE NORTH...BUT A NARROW LINE OF SHOWERS HAS DEVELOPED AND
WILL PUSH ACROSS AREAS NEAR THE TENNESSEE BORDER OVER THE NEXT
SEVERAL HOURS. UPDATED FORECAST TO REFINE THE POPS OVER THE NEXT
SEVERAL HOURS. FOG HAS LIFTED A BIT ACROSS THE AREA...BUT STILL
SEEING A FEW SPOTS ON THE RIDGES REPORTING SOME DENSE FOG...SO WILL
MAINTAIN THE FOG IN THE FORECAST. ADJUSTED TEMPERATURES AND DEWPOINTS
TO REFLECT A BETTER TREND THROUGH THE REST OF THE NIGHT.
UPDATE ISSUED AT 642 PM EDT FRI OCT 10 2014
UPDATED TO REMOVE THUNDER AS BETTER INSTABILITY HAS SHIFTED SOUTH OF
OUR AREA. THUNDER CHANCES LOOK MINIMAL THROUGH TOMORROW GIVEN
INSTABILITY IS BOTTLED UP SOUTH OF THE FRONTAL BOUNDARY. THUS...PLAN
TO REMOVE ANY THUNDER CHANCES TOMORROW AS WELL. MEANWHILE...FOG HAS
DEVELOPED QUICKLY ON THE RIDGES THIS EVENING AND HAS BECOME LOCALLY
DENSE. PLAN TO ADD FOG INTO THE FORECAST TONIGHT AND INCLUDE IT IN
THE HWO AS IT WILL CONTINUE TO BE DENSE IN PLACES THROUGH DAYBREAK.
SOME QUESTION AS TO HOW DENSE THE FOG WILL END UP IN THE
VALLEYS...BUT IF THE FOG CONTINUES TO EXPAND...MAY NEED TO LOOK AT
THE NEED FOR A DENSE FOG ADVISORY LATER ON. IN FACT... THE RAIN OUT
THERE NOW SHOULD BE MOVING ON THROUGH WITH A LULL EXPECTED AFTER
MIDNIGHT. AS THE BOUNDARY FINALLY SHIFTS SOUTHWARD. THIS WOULD PUT
ALL OF THE AREA ON THE NORTH SIDE OF THE BOUNDARY WITH THE POTENTIAL
FOR THE DENSE FOG. UPDATED FORECAST TO REFINE THE POPS THROUGH THE
REST OF THE NIGHT...FOCUSING THE BETTER POPS IN THE NORTH...WITH
LESSER POPS IN THE SOUTH AS THE SOUTHERN AREAS GET DRY SLOTTED.
FORECAST UPDATE HAS BEEN SENT.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 400 PM EDT FRI OCT 10 2014
19Z SFC ANALYSIS SHOWS A QUASI-STATIONARY FRONT LYING JUST NORTH OF
THE TENNESSEE AND KENTUCKY BORDER. THIS FRONT IS SERVING AS FOCUSING
MECHANISM FOR SHOWERS AND THUNDERSTORMS...BUT MAINLY TO THE SOUTH OF
THE STATE THUS FAR THIS AFTERNOON. THIS SHOULD CHANGE AS ANOTHER MID
LEVEL WAVE APPROACHES FROM THE WEST AND INDUCES A SFC WAVE TO MOVE
ALONG THE FRONT BRINGING RENEWED SHOWERS AND STORMS TO THE CWA THIS
EVENING AND INTO THE NIGHT. IN THE MEANTIME...JUST A FEW LIGHT
SHOWERS ARE FOUND THROUGH EAST KENTUCKY WITH SKIES MOSTLY CLOUDY.
THERE HAS BEEN SOME THINNING AND CLEAR PATCHES NOTED IN THE VISIBLE
SATELLITE LOOP OVER EAST KENTUCKY AND THIS SHOULD HELP BUILD SOME
EXTRA INSTABILITY OVER THE AREA THROUGH THE REST OF THE AFTERNOON.
THE THICKEST CLOUDS AND BEING NORTH OF THE FRONT HAS KEPT READINGS
LOCKED IN THE UPPER 50S IN THE FAR NORTH WHILE SOME 70 DEGREE REPORTS
HAVE BEEN NOTED IN THE FAR SOUTH. DEWPOINTS...MEANWHILE...ARE IN THE
LOW AND MID 60S SOUTH AND A BIT LOWER NORTH WHILE LIGHT WINDS ARE
FROM THE NORTHEAST NORTH OF JKL AND FROM THE SOUTHWEST TO THE SOUTH.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM AS THEY
ALL DEPICT FAST AND NEAR ZONAL FLOW MOVING OVER KENTUCKY INTO WHICH
A SHEARING MID LEVEL WAVE WILL PERIODICALLY RELEASE ITS ENERGY. A
HEALTHY BATCH IS ON ITS WAY HERE FOR THIS EVENING AND IS RESPONSIBLE
FOR THE CONVECTION CURRENTLY BUILDING OVER TENNESSEE THAT IS POISED
TO MOVE NORTHEAST INTO OUR AREA BY EVENING. THE REMNANTS OF THE PLAINS
TROUGH FALLS APART OVER THE OHIO VALLEY SATURDAY NIGHT. AS THIS ALL
HAPPENS...PLENTY OF UPPER LEVEL DIVERGENCE WILL BE FOUND OVER THE
REGION OWING TO A STRONG 300 MB JET PASSING BY TO THE NORTHEAST. HAVE
GONE WITH A BLEND OF THE MODELS WITH A LEAN TOWARD THE ECMWF
POSITIONS FOR THE FRONT...BUT FAVORED THE NAM12 QPF TOTALS...JUST
TRANSLATED A BIT SOUTH. ALSO INCORPORATED THE LATEST HRRR IN THE NEAR
TERM GRIDS.
SENSIBLE WEATHER WILL FEATURE A WET NIGHT WITH SHOWERS AND
THUNDERSTORMS EXPECTED TO KICK UP DURING THE EVENING AND FADE OUT
LATE IN THE NIGHT. PERIODS OF HEAVY RAIN WILL BE POSSIBLE. THE NEXT
WAVE MOVES OUT BY DAWN SATURDAY AS THE NEXT ONE STARTS TO HEAD THIS
WAY FROM THE MID MISSISSIPPI VALLEY BUT TAKING A BIT FURTHER SOUTH
TRACK. IT IS THESE TRACK SHIFTS THAT SHOULD SPARE ANY PARTICULAR PART
OF THE CWA A HIGHER FLOOD RISK DESPITE THE ROUNDS OF RAIN. HOWEVER...
SHOULD THE HEAVIER CELLS TRAIN OVER A SPOT LOCALIZED FLOODING WILL BE
POSSIBLE. THE RAIN WILL ACCUMULATE ENOUGH THAT THE DITCHES AND CREEKS
WILL CERTAINLY BE FULL AT TIMES AND THE LARGER RIVERS WILL RESPOND
AND START TO FILL UP AS WELL. FOR SATURDAY AND SATURDAY NIGHT THE
TRACK LOOKS TO FAVOR THE SOUTH AND LIKELY BE A LITTLE LESS ROBUST...
THOUGH EACH WAVE THROUGH EARLY SUNDAY...COULD HAVE PLACES THAT GET
HEAVY TO EXCESSIVE RAINS. THIS WILL CONTINUE TO BE ADDRESSED IN AN
ESFJKL. TEMPERATURES THROUGH THE SHORT TERM PERIOD WILL BE NEAR
NORMAL WITH A SMALL DIURNAL RANGE.
ONCE AGAIN USED THE CONSSHORT AS A STARTING POINT AGAIN FOR THE
T/TD/WIND GRIDS THROUGH THE FIRST 18-24 HOURS BEFORE GOING WITH THE
SUPERBLEND THEREAFTER. DID NOT SEE MANY TARGETS OF OPPORTUNITY FOR
TEMPERATURE IMPROVEMENTS IN THIS ENVIRONMENT SO ONLY MINOR TWEAKS
WERE MADE TO THE MAX AND MIN T GRIDS. AS FOR POPS...ENDED UP MOST
SIMILAR TO THE WETTER MAV NUMBERS THROUGH THE SHORT TERM PERIOD.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 335 PM EDT FRI OCT 10 2014
NOT MUCH AGREEMENT IN TIMING OF MAIN SYNOPTIC FEATURES THROUGH THE
EXTENDED...BUT BETTER AGREEMENT WITH ACTUAL PATTERN. HIGHLY
AMPLIFIED CENTRAL CONUS TROUGH WILL MOVE OUT OF THE GREAT PLAINS
EARLY IN THE PERIOD BEFORE FORMING A CUT OFF LOW SOMEWHERE OVER THE
MID MISSISSIPPI VALLEY...OR MIDWEST BY TUESDAY. FROM THERE FORWARD
THE 12Z GFS IS MUCH MORE PROGRESSIVE TAKING THIS LARGE SYSTEM INTO
THE NORTHEAST BY LATE WEDNESDAY. THE 12Z CANADIAN APPEARS TO BE
COMPROMISE OF THE GFS AND ECMWF. THE 0Z ECMWF...SLOWEST OF ALL THE
OPERATIONAL MODELS ROTATES THE LOW THROUGH THE LOWER OHIO VALLEY AT
A TURTLES PACE BEFORE LIFTING THE SYSTEM NORTHEAST THROUGH THE OHIO
VALLEY REGION LATE IN THE WEEK. NATIONAL GUIDANCE QUESTIONS HOW THE
ECMWF CAN KEEP THE CUT OFF LOW OVER THE LOWER OHIO VALLEY FOR SO
LONG WITHOUT BETTER SUPPORT FROM THE OVERALL UPPER LEVEL PATTERN
THAT WOULD PRODUCE THE SPLIT FLOW NECESSARY FOR ITS SOLUTION...AND
IN GENERAL THEY ARE NOT SEEING THOSE TYPES OF SIGNALS. THEREFORE
WILL TEND TO STICK WITH A BLENDED SOLUTION THROUGH THE EXTENDED.
AT THE SURFACE A QUASI STATIONARY FRONTAL BOUNDARY WILL REMAIN IN
THE REGION LIFTING NORTH AND SOUTH WITH EACH PASSING SFC WAVE AND/OR
UPPER LEVEL DISTURBANCE. THIS BOUNDARY LIFTS NORTH OF OUR AREA LATE
SUNDAY OR SUNDAY NIGHT AS THE MAIN STORM SYSTEM STRENGTHENS TO OUR
WEST. THERE IS MUCH LOWER CONFIDENCE IN THE FORECAST THEREAFTER BUT
CONSENSUS APPROACH SUGGEST THE POSSIBILITY OF SOME WRAP AROUND
MOISTURE...COLD AIR MASS INSTABILITY TYPE SHOWER ACTIVITY DURING THE
MID WEEK TIME FRAME.
AS FAR AS SIGNIFICANT WEATHER HIGHLIGHTS...STRONG LLJ MAY DEVELOP
OVER OUR AREA...AHEAD OF THE MAIN STORM SYSTEM LATE MONDAY INTO
TUESDAY AS H850 WIND SPEEDS INCREASE TO BETWEEN 50 AND 70 KTS. THESE
STRONGER WINDS COULD MIX DOWN CREATING THE POTENTIAL FOR SOME STRONG
STORMS AS AN OCCLUDED FRONT MAKES ITS WAY ACROSS THE AREA EITHER
LATE MONDAY OR TUESDAY. THIS THREAT WILL INCREASE SHOULD WE SEE
SIGNIFICANT AMOUNTS OF SUNLIGHT MONDAY. HOWEVER...THERE IS TOO MUCH
DIFFERENCES IN MODEL SOLUTIONS TO HAVE ANY CONFIDENCE IN TIMING AND
OTHER DETAILS AT THIS POINT. STRONGER...GUSTY WINDS SHOULD BE
EXPECTED BEHIND THE OCCLUDED FRONT AS WELL...WHICH MAY BE REALIZED
AS EARLY AS TUESDAY. ANOTHER HIGHLIGHT IS THE POTENTIAL FOR LOCALLY
HEAVY RAINFALL. WHILE FORECAST SOUNDINGS DO INDICATE ABOVE NORMAL
PWATS...TIMING OF DISTURBANCES MOVING THROUGH THE AREA WOULD PROVIDE
SOME DECENT BREAKS...RECOVERY TIME BETWEEN SUCCESSIVE BOUTS OF RAIN.
THOUGHTS ARE THAT TRAINING OF CELLS MAY CREATE A MUCH GREATER THREAT
OF HEAVY RAIN...ESPECIALLY OVER SATURATED GROUND. IN ADDITION...
TOTAL RAINFALL WILL BE SPREAD OUT OVER AN EXTENDED PERIOD OF TIME.
THEREFORE FLASH FLOODING IS NOT EXPECTED TO BE AS GREAT A THREAT AS
IT MIGHT NORMALLY BE. HOWEVER SOME MINOR FLOODING OF LARGER CREEKS
AND STREAMS...AND EVENTUALLY AREA RIVERS...WILL BE POSSIBLE OVER THE
LONG HAUL. ATTM THE CURRENT HYDROLOGIC OUTLOOK HANDLES OUR CURRENT
SITUATION WELL.
IN GENERAL SENSIBLE WEATHER LOOKS QUITE UNSTABLE THROUGH TUESDAY...
BUT GRADUALLY IMPROVES AND DRIES OUT THEREAFTER WITH ONLY SOME
INSTABILITY SHOWERS TO DEAL WITH WED-THU. STUCK TO A BLEND OF
GUIDANCE FOR TEMPS. WITH SUCH A STRONG SOUTHERLY JET AND FETCH OF
AIR INTO THE REGION MONDAY NUDGED TEMPS UP CLOSER TO THE WARMER GFS
GUIDANCE VERSUS THE BLEND. LOOKING FOR ABOVE NORMAL TEMPS THROUGH
MONDAY NIGHT...THEN NEAR OR BELOW NORMAL TEMPS THROUGH THE REMAINDER
OF THE PERIOD. SHOULD THE ECMWF EVENTUALLY TURN OUT TO BE THE BEST
SOLUTION...TUESDAY/S HIGH AND POSSIBLY TUESDAY NIGHTS LOW TEMPS
WOULD COME IN WARMER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 115 AM EDT SAT OCT 11 2014
A LOW PRESSURE DISTURBANCE CONTINUES TO PUSH ACROSS THE AREA
PRODUCING SCATTERED TO NUMEROUS SHOWERS ACROSS EASTERN KENTUCKY. AS
THIS WAVE DEPARTS OVERNIGHT...CEILINGS WILL FALL TO NEAR OR BELOW
AIRPORT MINIMUMS AND THIS WILL CONTINUE THROUGH MUCH OF THE MORNING.
SOME SLIGHT IMPROVEMENT IS POSSIBLE THROUGH THE DAY SATURDAY...BUT
CEILINGS WILL NOT GET MUCH ABOVE AIRPORT MINIMUMS. CEILINGS MAY FALL
BACK BELOW AIRPORT MINIMUMS TONIGHT AS THE AREA REMAINS NORTH OF THE
FRONTAL BOUNDARY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...GREIF
LONG TERM...RAY
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1038 PM CDT SUN OCT 12 2014
.DISCUSSION...
VERY BUSY EVENING...AS SCT CONVECTION RAPIDLY DEVELOPED/BECAME SVR
ACROSS PORTIONS OF EXTREME ERN TX/N LA WITHIN THE WARM SECTOR
ALONG/S OF A WARM FRONT. THIS FRONT CONTINUES TO RAPIDLY MIX NNW
THIS EVENING...WITH VERY LOW STRATUS/PATCHY FG STILL HANGING TOUGH
ATTM ACROSS PORTIONS OF EXTREME NE TX/SE OK/SW AR ALONG/N OF THE
I-30 CORRIDOR. THE INITIAL SHORTWAVE THAT TRIGGERED THE SCT SVR
CONVECTION EARLIER THIS EVENING HAS EJECTED NE OF THE AREA...WITH
ALL EYES FOCUSED TO OUR W WITH THE LONGWAVE TROUGH DIVING SE INTO
THE PLAINS. MOSAIC RADARS ALREADY INDICATING A DEVELOPING SQUALL
LINE OVER CNTRL OK/NW TX...ALONG A STRONG COLD FRONT THAT HAS
MOVED THROUGH THE TX PANHANDLE INTO WRN OK. THE PRESSURE GRADIENT
HAS TIGHTENED OVER THE SRN PLAINS THIS EVENING...WITH STRONG
FRONTAL CONVERGENCE CONTRIBUTING TO SVR CONVECTION...WHERE STRONG
DIFFLUENCE IN THE RRQ OF THE UPPER JET HAS SET UP.
SFC WINDS OVER OUR REGION HAS NOT INCREASED MUCH AS EARLIER
ANTICIPATED...WITH THE GFS MUCH TOO FAST WITH INCREASING WINDS
AHEAD OF AN INTENSIFYING SFC LOW THAT WILL SPREAD SE INTO CNTRL
OK LATE. HAVE DELAYED THE LAKE WIND ADVISORY UNTIL 4AM
MONDAY...AND HAVE MAINTAINED IT THROUGH THE ORIGINAL 7PM EXPIRATION
TIME. HAVE ALSO LOWERED POPS A TAD ACROSS EXTREME E TX/NW
LA/SCNTRL AR AND REMOVED HEAVY RAINFALL WORDING...WITH THE NEW 00Z NAM
IN GOOD AGREEMENT WITH THE HRRR WITH PRE-FRONTAL CONVECTION
DEVELOPING AHEAD OF THE SQUALL LINE MOVING INTO EXTREME SE OK/NE
TX AFTER 08Z. HAVE ALSO ADDED SVR WORDING TO E TX/SE OK AS WELL
LATE...AND ADDED IT AREAWIDE MONDAY AS THE SQUALL LINE RACES
ACROSS THE REGION. WITH THE HRRR AND 00Z NAM SUGGESTING A FASTER
PROGRESSION OF THE SQUALL LINE...HOPEFULLY THIS AND THE MORNING
LOW STRATUS WILL DETER DESTABILIZATION SOME OVER NCNTRL LA/SCNTRL
AR. HOWEVER...A SLOWER EWD PROGRESSION WOULD SUGGEST MORE
HEATING/INSTABILITY WITHIN A STRONGLY SHEARED ENVIRONMENT...WHICH
WOULD RESULT IN AN ENHANCED SVR THREAT.
AM CONCERNED FOR POTENTIAL FLOODING ISSUES LATE TONIGHT/MONDAY
MORNING ESPECIALLY OVER SE OK/ADJACENT SECTIONS OF SW AR /OUR NRN
COUNTIES/...AS ANY PRE-SQUALL LINE CONVECTION WOULD TEND TO TRAIN
OVER THESE AREAS...RESULTING IN 2-4+ INCH QPF/S OVER ALREADY
SATURATED GROUNDS. WILL NOT ISSUE A FLASH FLOOD WATCH FOR THESE
AREAS JUST YET...AS THE SQUALL LINE MAY QUICKLY OVERTAKE THE PRE-
FRONTAL CONVECTION AND LIMIT TRAINING. HOWEVER...LOCALIZED FLASH
FLOODING WILL REMAIN POSSIBLE.
DID ADJUST MIN TEMPS SLIGHTLY TONIGHT...WITH CURRENT TEMPS SEVERAL
DEGREES BELOW THE ORIGINAL FORECAST VALUES. HOWEVER...TEMPS SHOULD
SLOWLY WARM OVERNIGHT AS WINDS/LOW STRATUS INCREASES ACROSS THE
NWN EXPANDING WARM SECTOR.
ZONE UPDATE/NPW ALREADY OUT...GRIDS WILL BE AVAILABLE SHORTLY.
15
&&
.PREV DISCUSSION... /ISSUED 728 PM CDT SUN OCT 12 2014/
AVIATION...
FOR THE 13/00Z TAFS...SCT CONVECTION AFFECTING OUR N LA/S AR SITES
EARLY THIS EVENING AS A SFC WARM FRONT EXTENDS ALONG AND NEAR THE
I-20 CORRIDOR AND AN UPPER LEVEL DISTURBANCE SHIFTS OVERHEAD. THIS
CONVECTION HAS PRODUCED GUSTY WINDS AND HEAVY DOWNPOURS...WITH LOW
CIGS/VSBYS AT TIMES. EXPECT A GRADUAL LOWERING OF CIGS TO MVFR/IFR
OVERNIGHT AS CONVECTION WILL DIMINISH THROUGH EARLY MONDAY MORNING.
HOWEVER...ANOTHER LINE OF SHWRS/TSTMS WILL BEGIN TO SPREAD EWRD AS
WE SHIFT AHEAD TO MID/LATE MORNING AHEAD OF A STRONG COLD FRONT IN
CNTRL TX/OK. THESE STORMS WILL RACE RAPIDLY EWRD ACROSS THE REGION
AND PRODUCE STRONG AND POTENTIALLY DAMAGING STRAIGHT-LINE WINDS IN
ADVANCE OF THE FRONT. TIMING PUTS THE LINE NEAR TYR/GGG/TXK FROM
12Z-15Z...15Z-18Z AT LFK/SHV/ELD AND MLU AROUND 18Z-21Z. CIGS WILL
IMPROVE SLIGHTLY AT OUR WRN SITES IN E TX AND POSSIBLY SHV/TXK
NEAR THE END OF THE TAF PERIOD BUT SOME WRAP AROUND MOISTURE FROM
THE UPPER LEVEL LOW MAY KEEP CLOUDS FROM CLEARLY QUITE AS QUICKLY
BEHIND THE FRONT. THE OTHER CONCERN WORTH NOTING WILL BE THE
STRONG WINDS NOT ASSOCIATED WITH CONVECTION AS S/SW FLOW WILL PICK
UP AFTER 13/06Z AND WIND SPEEDS WILL INCREASE TO 12-18 KTS WITH
HIGHER GUSTS APPROACHING 25-30 KTS. W/NW WINDS EXPECTED BEHIND
THE FRONT WITH SPEEDS DROPPING OFF AFTER 14/00Z. /19/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 67 79 53 74 48 / 50 100 10 10 10
MLU 68 82 55 73 50 / 40 100 40 10 10
DEQ 64 75 52 71 42 / 80 100 30 10 10
TXK 65 77 52 71 48 / 60 100 20 10 10
ELD 67 78 52 70 46 / 50 100 30 10 10
TYR 68 74 51 75 49 / 70 100 10 10 10
GGG 66 77 52 76 46 / 50 100 10 10 10
LFK 70 82 52 78 48 / 30 100 10 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...LAKE WIND ADVISORY FROM 4 AM TO 7 PM CDT MONDAY FOR THE
FOLLOWING ZONES: ARZ050-051-059>061-070>073.
LA...LAKE WIND ADVISORY FROM 4 AM TO 7 PM CDT MONDAY FOR THE
FOLLOWING ZONES: LAZ001>006-010>014-017>022.
OK...LAKE WIND ADVISORY FROM 4 AM TO 7 PM CDT MONDAY FOR THE
FOLLOWING ZONES: OKZ077.
TX...LAKE WIND ADVISORY FROM 4 AM TO 7 PM CDT MONDAY FOR THE
FOLLOWING ZONES:
TXZ096-097-108>112-124>126-136>138-149>153-165>167.
&&
$$
15
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1150 PM EDT SUN OCT 12 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 330 PM EDT SUN OCT 12 2014
A WET WEEK IS ON TAP ACROSS THE AREA...ALONG WITH WARMER
TEMPERATURES THROUGH MOST OF THE WEEK. THE LEADING EDGE OF A LOW
PRESSURE SYSTEM WILL MOVE IN ACROSS THE AREA TONIGHT. THIS WILL
BRING A FEW SHOWERS INTO THE AREA TONIGHT. SHOWERS AND STORMS WILL
BECOME MORE NUMEROUS AND HEAVIER BY MONDAY NIGHT AND TUESDAY. RAIN
WILL NOT BE AS HEAVY BEYOND TUESDAY...HOWEVER SHOWERS WILL BE
POSSIBLE THROUGH MOST OF THE REST OF THE WEEK.
&&
.UPDATE...
ISSUED AT 1005 PM EDT SUN OCT 12 2014
I REFOCUSED THE POPS FOR OVERNIGHT EARLIER AND MORE TO THE
SOUTHEAST. THE LATEST RAP DATA (01Z) SHOWS THE AREA OF SHOWERS
CURRENTLY MOVING OVER WESTERN SECTIONS WIDELY SCATTERED AND ARE
NOT ALL THAT HEAVY. THIS AREA OF SHOWERS IS THE DEEP MOISTURE
MOVING IN BUT THE PROBLEM IS WHILE THERE IS LIFT IN THE DGZ...
THEM MEAN RH IN THAT LAYER IS MOSTLY BELOW 50 PCT. THE AREA WITH
RH OVER 80 PCT STAYS OVER LAKE MICHIGAN AND LIFTS NORTH OF THE
LAKE BY 06Z. THE AREA OF CONDENSATION PRESSURE DEFICITS UNDER 10
MB IS RATHER NARROW (NEAR 700 MB) AND MOVES THROUGH THE CWA
BETWEEN 03Z AND 09Z. ADD TO THIS A LACK OF SIGNIFICANT LOW LEVEL
JET AND I HAVE TO BELIEVE ANY SHOWER ACTIVITY WILL BE LIGHT AND
NOT LAST VERY LONG. THE INSTABILITY IS LACKING FOR THUNDERSTORMS SO
THAT IS NOT MUCH OF CONCERN TONIGHT EITHER. FOR THE MOST PART WHAT
WILL BE SEEN IS A LOWERING CLOUD DECK AND TEMPERATURES HOLDING
STEADY OR SLOWLY RISING AS THE CLOUDS THICKEN. AT THIS POINT I DO
NOT SEE MUCH OF DENSE FOG PROBLEM.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 330 PM EDT SUN OCT 12 2014
THE MAIN CHALLENGES IN THE SHORT TERM WILL BE PCPN TRENDS THROUGH
THE PERIOD...AND WHAT...IF ANY THREAT OF SEVERE WEATHER EXISTS
MAINLY THROUGH TUE.
THE STRETCH OF NICE WEATHER THE AREA HAS HAD OVER THE PAST FEW DAYS
IS IN THE PROCESS OF COMING TO AN END WITH THE INCREASING CLOUD
COVER NOW ENTERING THE CWFA FROM THE SW. WE ARE SEEING THE INITIAL
SURGE OF MOISTURE TRANSPORT AHEAD OF THE LEADING WAVE NOW ACROSS THE
MO/IL AREA. THE FIRST SHOWERS ARE NOW PRESENT JUST SW OF CHICAGO...
AND WE WILL SEE PCPN CHCS INCREASE THROUGH THE EVENING. THE BEST
CHCS OF RAIN TONIGHT WILL BE ACROSS THE SRN TWO-THIRDS OF THE CWFA
AS THE BEST MOISTURE TRANSPORT MOVES ACROSS THE SE PORTION OF THE
AREA. THUNDER SHOULD HOLD OFF FOR TONIGHT WITH NO REAL SFC BASED OF
ELEVATED INSTABILITY PRESENT.
WE SHOULD SEE A LULL IN THE MORE WIDESPREAD SHOWER ACTIVITY DURING
THE DAY ON MON. WE WILL BE INBETWEEN THE DEPARTING WAVE FROM TONIGHT
AND THE MAIN PORTION OF THE SYSTEM THAT WILL COME IN MON EVENING.
THERE STILL COULD BE A SHOWER OR STORM POP UP ON MON AFTERNOON WITH
ONGOING WEAKER MOISTURE TRANSPORT. SOME BREAKS IN THE CLOUDS WILL BE
POSSIBLE AND TEMPS WILL LIKELY SNEAK UP TO 70 DOWN SOUTH. SOME SFC
BASED INSTABILITY COULD DEVELOP WITH THE TEMPS AND DEW POINTS ON THE
RISE. IF A STORM WERE TO DEVELOP...INCREASING WINDS ALOFT WOULD
SUPPORT SOME STRONGER WIND GUST POTENTIAL. AT THIS TIME WE ARE NOT
EXPECTING WIDESPREAD CONVECTION MON AFTERNOON.
WE WILL SEE MORE WIDESPREAD RAIN SHOWERS AND SOME EMBEDDED THUNDER
MOVE IN FOR MON NIGHT AND TUE. THIS IS WHEN THE CORE OF THE 50+ KNOT
LLJ AND STRONGEST MOISTURE TRANSPORT TAKES PLACE OVER THE AREA. THE
FOCUS WILL BE ON THE NW CORNER OF THE CWFA FOR HIGHEST RAINFALL
AMOUNTS. THIS IS DUE TO THE FRONTAL BOUNDARY SETTLED OVER THE
CWFA...AND THE STRONG OVERRUNNING THAT WILL BE TAKING PLACE. THE
RAIN WILL GRADUALLY SPREAD TO THE EAST AS THE TRIPLE POINT OF THE
SYSTEM SLOWLY MOVES JUST S AND EVENTUALLY EAST OF THE AREA.
INSTABILITY LOOKS TO BE MAINLY ELEVATED AFTER MON AFTERNOON. THIS
SHOULD LIMIT THE SEVERE POTENTIAL FOR THE AREA FROM MON NIGHT AND
BEYOND WITH WEAK ELEVATED INSTABILITY PRESENT.
MAINLY SHOWERS WILL CONTINUE ACROSS THE AREA FOR TUE NIGHT. THE
OCCLUDED FRONT BECOMES NEARLY STATIONARY OVER THE AREA AT THAT TIME
AS THE PARENT LOW DOES NOT MOVE MUCH AT ALL. THE BEST CHANCE FOR
RAIN WILL BE ACROSS THE CENTRAL AND NRN PORTION OF THE CWFA ON TUE
NIGHT AS THE DRY SLOT TRIES TO WORK IN ACROSS THE SOUTH.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 330 PM EDT SUN OCT 12 2014
THE UNSETTLED/SHOWERY PATTERN IS EXPECTED TO CONTINUE IN THE LONG
TERM PERIOD AS THE SLOW MOVING UPPER LOW DRIFTS SLOWLY
NORTH/NORTHEAST. TEMPERATURES WILL ACTUALLY BE A FEW DEGREES ABOVE
NORMAL WEDNESDAY THROUGH FRIDAY WITH HIGHS MOSTLY IN THE 60S. CANT
RULE OUT A FEW THUNDERSTORMS IN THE MID TO LATE WEEK PERIOD UNDER
THE UPPER LOW... ESPECIALLY DURING THE AFTERNOON AND EARLY EVENING
HOURS... BUT LEFT THAT OUT OF THE FCST FOR NOW.
THE GFS CONTINUES TO LOOK TOO PROGRESSIVE WITH THE UPPER LOW/TROUGH
BEYOND 72 HOURS AND HAS STRUGGLED WITH THIS IN EVERY MODEL RUN.
CONTINUE TO PREFER THE SLOWER ECMWF SOLUTION WHICH SHOWS THE UPPER
LOW EVENTUALLY JUST BEING ABSORBED IN WITH THE DIGGING NRN STREAM
TROUGH DROPPING DOWN FROM THE NORTHWEST TOWARD NEXT WEEKEND.
CONFIDENCE IS ALREADY MEDIUM TO HIGH REGARDING AN INTRUSION OF SUB
ZERO H8 AIR FRIDAY NIGHT WITH CONSIDERABLE CLOUDINESS AND SCATTERED
LAKE EFFECT RAIN SHOWERS IN THE CYCLONIC FLOW BEHIND THE COLD FRONT
ON SATURDAY. MODELS HAVE BEEN SHOWING THIS SCENARIO FOR SEVERAL RUNS
NOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1147 PM EDT SUN OCT 12 2014
IFR/MVFR CIGS HAVE BEEN SLOWLY BUT STEADILY MOVING NORTHEAST
ACROSS ILLINOIS INTO SW LWR MI THIS EVENING. THE LOWER CIGS/VSBYS
WILL MOVE ACROSS THE TAF SITES OVERNIGHT. CIBS BLO 1K FT ARE
EXPECTED AT SUNRISE ALONG WITH SHOWERS. CIGS WILL RISE A BIT TO
MVFR MONDAY AFTERNOON.
&&
.MARINE...
ISSUED AT 330 PM EDT SUN OCT 12 2014
NO MARINE HEADLINES WILL BE ISSUED WITH THIS FCST PACKAGE. AN
INITIAL SURGE IN WINDS WELL ABOVE THE SFC WILL COME IN TONIGHT...
HOWEVER WE DO NOT EXPECT THEM TO REACH DOWN TO THE SFC WITH STRONG
WARMING TAKING PLACE UP ABOVE AND AN OFFSHORE COMPONENT TO THE WIND.
WE DO EXPECT AT LEAST SCA CONDITIONS FOR MON NIGHT AND TUE AS THE
SECOND AND STRONGER SURGE OF WIND COMES IN. GALES COULD BE
APPROACHED AT THAT TIME.
&&
.HYDROLOGY...
ISSUED AT 330 PM EDT SUN OCT 12 2014
WE CONTINUE TO FOCUS ON MOST OF THIS WEEK WITH RAIN EXPECTED DURING
THAT TIME...WHERE WOULD COULD END UP WITH HEAVIER AMOUNTS OVERALL. A
GENERAL 1 TO 3 INCHES OF RAIN IS EXPECTED WITH HIGHER AMOUNTS TO THE
NW...AND LESSER AMOUNTS TO THE SE. THE MAJORITY OF THE RAIN WILL
FALL FROM MON NIGHT THROUGH TUE WHEN THE STRONGEST WARM AND MOIST
ADVECTION TAKES PLACE AHEAD OF THE SYSTEM. PWATS ARE STILL FCST TO
APPROACH 1.75 INCHES MON NIGHT AND TUE WHICH IS AT...OR ABOVE THE
99TH PERCENTILE FOR MID OCTOBER.
RIVER LEVELS HAVE RECOVERED A BIT OVER THE PAST FEW DAYS WITH THE
DRY WEATHER WE HAVE HAD. THIS RAIN WILL CAUSE SIGNIFICANT RISES ON
THE AREA RIVERS...ESPECIALLY ACROSS THE MUSKEGON RIVER BASIN WHERE
THE HEAVIER RAIN WILL BE FOUND. WE WILL CONTINUE TO MONITOR THE NEED
FOR HEADLINES ACROSS THE AREA.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...MEADE
AVIATION...93
HYDROLOGY...NJJ
MARINE...NJJ
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1006 PM EDT SUN OCT 12 2014
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 330 PM EDT SUN OCT 12 2014
A WET WEEK IS ON TAP ACROSS THE AREA...ALONG WITH WARMER
TEMPERATURES THROUGH MOST OF THE WEEK. THE LEADING EDGE OF A LOW
PRESSURE SYSTEM WILL MOVE IN ACROSS THE AREA TONIGHT. THIS WILL
BRING A FEW SHOWERS INTO THE AREA TONIGHT. SHOWERS AND STORMS WILL
BECOME MORE NUMEROUS AND HEAVIER BY MONDAY NIGHT AND TUESDAY. RAIN
WILL NOT BE AS HEAVY BEYOND TUESDAY...HOWEVER SHOWERS WILL BE
POSSIBLE THROUGH MOST OF THE REST OF THE WEEK.
&&
.UPDATE...
ISSUED AT 1005 PM EDT SUN OCT 12 2014
I REFOCUSED THE POPS FOR OVERNIGHT EARLIER AND MORE TO THE
SOUTHEAST. THE LATEST RAP DATA (01Z) SHOWS THE AREA OF SHOWERS
CURRENTLY MOVING OVER WESTERN SECTIONS WIDELY SCATTERED AND ARE
NOT ALL THAT HEAVY. THIS AREA OF SHOWERS IS THE DEEP MOISTURE
MOVING IN BUT THE PROBLEM IS WHILE THERE IS LIFT IN THE DGZ...
THEM MEAN RH IN THAT LAYER IS MOSTLY BELOW 50 PCT. THE AREA WITH
RH OVER 80 PCT STAYS OVER LAKE MICHIGAN AND LIFTS NORTH OF THE
LAKE BY 06Z. THE AREA OF CONDENSATION PRESSURE DEFICITS UNDER 10
MB IS RATHER NARROW (NEAR 700 MB) AND MOVES THROUGH THE CWA
BETWEEN 03Z AND 09Z. ADD TO THIS A LACK OF SIGNIFICANT LOW LEVEL
JET AND I HAVE TO BELIEVE ANY SHOWER ACTIVITY WILL BE LIGHT AND
NOT LAST VERY LONG. THE INSTABILITY IS LACKING FOR THUNDERSTORMS SO
THAT IS NOT MUCH OF CONCERN TONIGHT EITHER. FOR THE MOST PART WHAT
WILL BE SEEN IS A LOWERING CLOUD DECK AND TEMPERATURES HOLDING
STEADY OR SLOWLY RISING AS THE CLOUDS THICKEN. AT THIS POINT I DO
NOT SEE MUCH OF DENSE FOG PROBLEM.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 330 PM EDT SUN OCT 12 2014
THE MAIN CHALLENGES IN THE SHORT TERM WILL BE PCPN TRENDS THROUGH
THE PERIOD...AND WHAT...IF ANY THREAT OF SEVERE WEATHER EXISTS
MAINLY THROUGH TUE.
THE STRETCH OF NICE WEATHER THE AREA HAS HAD OVER THE PAST FEW DAYS
IS IN THE PROCESS OF COMING TO AN END WITH THE INCREASING CLOUD
COVER NOW ENTERING THE CWFA FROM THE SW. WE ARE SEEING THE INITIAL
SURGE OF MOISTURE TRANSPORT AHEAD OF THE LEADING WAVE NOW ACROSS THE
MO/IL AREA. THE FIRST SHOWERS ARE NOW PRESENT JUST SW OF CHICAGO...
AND WE WILL SEE PCPN CHCS INCREASE THROUGH THE EVENING. THE BEST
CHCS OF RAIN TONIGHT WILL BE ACROSS THE SRN TWO-THIRDS OF THE CWFA
AS THE BEST MOISTURE TRANSPORT MOVES ACROSS THE SE PORTION OF THE
AREA. THUNDER SHOULD HOLD OFF FOR TONIGHT WITH NO REAL SFC BASED OF
ELEVATED INSTABILITY PRESENT.
WE SHOULD SEE A LULL IN THE MORE WIDESPREAD SHOWER ACTIVITY DURING
THE DAY ON MON. WE WILL BE INBETWEEN THE DEPARTING WAVE FROM TONIGHT
AND THE MAIN PORTION OF THE SYSTEM THAT WILL COME IN MON EVENING.
THERE STILL COULD BE A SHOWER OR STORM POP UP ON MON AFTERNOON WITH
ONGOING WEAKER MOISTURE TRANSPORT. SOME BREAKS IN THE CLOUDS WILL BE
POSSIBLE AND TEMPS WILL LIKELY SNEAK UP TO 70 DOWN SOUTH. SOME SFC
BASED INSTABILITY COULD DEVELOP WITH THE TEMPS AND DEW POINTS ON THE
RISE. IF A STORM WERE TO DEVELOP...INCREASING WINDS ALOFT WOULD
SUPPORT SOME STRONGER WIND GUST POTENTIAL. AT THIS TIME WE ARE NOT
EXPECTING WIDESPREAD CONVECTION MON AFTERNOON.
WE WILL SEE MORE WIDESPREAD RAIN SHOWERS AND SOME EMBEDDED THUNDER
MOVE IN FOR MON NIGHT AND TUE. THIS IS WHEN THE CORE OF THE 50+ KNOT
LLJ AND STRONGEST MOISTURE TRANSPORT TAKES PLACE OVER THE AREA. THE
FOCUS WILL BE ON THE NW CORNER OF THE CWFA FOR HIGHEST RAINFALL
AMOUNTS. THIS IS DUE TO THE FRONTAL BOUNDARY SETTLED OVER THE
CWFA...AND THE STRONG OVERRUNNING THAT WILL BE TAKING PLACE. THE
RAIN WILL GRADUALLY SPREAD TO THE EAST AS THE TRIPLE POINT OF THE
SYSTEM SLOWLY MOVES JUST S AND EVENTUALLY EAST OF THE AREA.
INSTABILITY LOOKS TO BE MAINLY ELEVATED AFTER MON AFTERNOON. THIS
SHOULD LIMIT THE SEVERE POTENTIAL FOR THE AREA FROM MON NIGHT AND
BEYOND WITH WEAK ELEVATED INSTABILITY PRESENT.
MAINLY SHOWERS WILL CONTINUE ACROSS THE AREA FOR TUE NIGHT. THE
OCCLUDED FRONT BECOMES NEARLY STATIONARY OVER THE AREA AT THAT TIME
AS THE PARENT LOW DOES NOT MOVE MUCH AT ALL. THE BEST CHANCE FOR
RAIN WILL BE ACROSS THE CENTRAL AND NRN PORTION OF THE CWFA ON TUE
NIGHT AS THE DRY SLOT TRIES TO WORK IN ACROSS THE SOUTH.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 330 PM EDT SUN OCT 12 2014
THE UNSETTLED/SHOWERY PATTERN IS EXPECTED TO CONTINUE IN THE LONG
TERM PERIOD AS THE SLOW MOVING UPPER LOW DRIFTS SLOWLY
NORTH/NORTHEAST. TEMPERATURES WILL ACTUALLY BE A FEW DEGREES ABOVE
NORMAL WEDNESDAY THROUGH FRIDAY WITH HIGHS MOSTLY IN THE 60S. CANT
RULE OUT A FEW THUNDERSTORMS IN THE MID TO LATE WEEK PERIOD UNDER
THE UPPER LOW... ESPECIALLY DURING THE AFTERNOON AND EARLY EVENING
HOURS... BUT LEFT THAT OUT OF THE FCST FOR NOW.
THE GFS CONTINUES TO LOOK TOO PROGRESSIVE WITH THE UPPER LOW/TROUGH
BEYOND 72 HOURS AND HAS STRUGGLED WITH THIS IN EVERY MODEL RUN.
CONTINUE TO PREFER THE SLOWER ECMWF SOLUTION WHICH SHOWS THE UPPER
LOW EVENTUALLY JUST BEING ABSORBED IN WITH THE DIGGING NRN STREAM
TROUGH DROPPING DOWN FROM THE NORTHWEST TOWARD NEXT WEEKEND.
CONFIDENCE IS ALREADY MEDIUM TO HIGH REGARDING AN INTRUSION OF SUB
ZERO H8 AIR FRIDAY NIGHT WITH CONSIDERABLE CLOUDINESS AND SCATTERED
LAKE EFFECT RAIN SHOWERS IN THE CYCLONIC FLOW BEHIND THE COLD FRONT
ON SATURDAY. MODELS HAVE BEEN SHOWING THIS SCENARIO FOR SEVERAL RUNS
NOW.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 727 PM EDT SUN OCT 12 2014
OUR VFR WEATHER PATTERN IS ABOUT TO COME TO AN END THIS EVENING.
VFR CONDITIONS WILL FADE TO IFR BY 09Z-12Z. THEN IFR /MVFR
CONDITIONS SHOULD CONTINUE INTO TUESDAY AFTERNOON AND LIKELY BEYOND
THAT.
A SYSTEM FROM THE SOUTHERN PLAINS IS SENDING DEEP MOISTURE
TOWARD THE GREAT LAKES SO WE WILL SEE A "WARM FRONT" WEATHER
PATTERN OVER THE NEXT 24 HOURS. THE MID CLOUDS EARLY THIS EVENING
WILL LOWER TO MVFR CIGS BY 06Z OR SO. AT THAT POINT A FEW SHOWERS
ARE POSSIBLE (I PUT VCSH FOR THAT). TOWARD MORNING AS THE LOW
LEVEL JET IS AIMED AT THIS AREA WE SHOULD SEE A PERIOD OF SHOWERS
IN THE 09Z- 15Z TIME FRAME. SINCE SURFACE DEW POINTS IN THE WARM
AIR HEADING THIS WAY ARE HIGHER THAN THE FORECAST SURFACE
TEMPERATURES AT THE TAF SITES BY MID MORNING MONDAY.... I WOULD
EXPECT EXTENSIVE IFR CIGS AND VSBY WITH DRIZZLE AND FOG ONCE THE
SHOWERS MOVE OUT OF THE AREA. WE COULD SEE CONDITIONS IMPROVE TO
MVFR BY EARLY AFTERNOON. THE PRIMARY RAIN AREA FROM THIS SYSTEM
WILL NOT MOVE INTO SOUTHWEST MICHIGAN UNTIL AFTER 06Z TUESDAY.
THERE IS A THREAT FOR THUNDERSTORMS MONDAY BUT GIVEN THE EXTENSIVE
LOW CLOUDS AND THE LACK OF DEEP FORCING DURING THE DAY TIME HOURS
OF MONDAY OVER THE TAF SITES ON SOUTHWEST LOWER MICHIGAN I AM
THINKING THUNDERSTORMS ARE NOT LIKELY SO THEY ARE NOT INCLUDED THE
THE TAFS AT THIS POINT. THIS WILL HAVE TO BE WATCHED OVER TIME
THROUGH.
&&
.MARINE...
ISSUED AT 330 PM EDT SUN OCT 12 2014
NO MARINE HEADLINES WILL BE ISSUED WITH THIS FCST PACKAGE. AN
INITIAL SURGE IN WINDS WELL ABOVE THE SFC WILL COME IN TONIGHT...
HOWEVER WE DO NOT EXPECT THEM TO REACH DOWN TO THE SFC WITH STRONG
WARMING TAKING PLACE UP ABOVE AND AN OFFSHORE COMPONENT TO THE WIND.
WE DO EXPECT AT LEAST SCA CONDITIONS FOR MON NIGHT AND TUE AS THE
SECOND AND STRONGER SURGE OF WIND COMES IN. GALES COULD BE
APPROACHED AT THAT TIME.
&&
.HYDROLOGY...
ISSUED AT 330 PM EDT SUN OCT 12 2014
WE CONTINUE TO FOCUS ON MOST OF THIS WEEK WITH RAIN EXPECTED DURING
THAT TIME...WHERE WOULD COULD END UP WITH HEAVIER AMOUNTS OVERALL. A
GENERAL 1 TO 3 INCHES OF RAIN IS EXPECTED WITH HIGHER AMOUNTS TO THE
NW...AND LESSER AMOUNTS TO THE SE. THE MAJORITY OF THE RAIN WILL
FALL FROM MON NIGHT THROUGH TUE WHEN THE STRONGEST WARM AND MOIST
ADVECTION TAKES PLACE AHEAD OF THE SYSTEM. PWATS ARE STILL FCST TO
APPROACH 1.75 INCHES MON NIGHT AND TUE WHICH IS AT...OR ABOVE THE
99TH PERCENTILE FOR MID OCTOBER.
RIVER LEVELS HAVE RECOVERED A BIT OVER THE PAST FEW DAYS WITH THE
DRY WEATHER WE HAVE HAD. THIS RAIN WILL CAUSE SIGNIFICANT RISES ON
THE AREA RIVERS...ESPECIALLY ACROSS THE MUSKEGON RIVER BASIN WHERE
THE HEAVIER RAIN WILL BE FOUND. WE WILL CONTINUE TO MONITOR THE NEED
FOR HEADLINES ACROSS THE AREA.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...MEADE
AVIATION...WDM
HYDROLOGY...NJJ
MARINE...NJJ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
905 PM EDT SUN OCT 12 2014
.UPDATE...
ISSUED AT 904 PM EDT SUN OCT 12 2014
SHOWERS AND/OR SPRINKLES HAVE MOVED INTO WESTERN UPPER MICHIGAN IN
ADVANCE OF THE WEAK UPPER DISTURBANCE ALOFT. WITH THE DWPTS STILL IN
THE LOWER 30S...DO NOT EXPECT MUCH MORE THAN A FEW
SPRINKLES/SHOWERS. HOWEVER...HAVE INTRODUCED ISOLATED SHOWERS MOVING
ACROSS THE AREA OVERNIGHT. IN FACT...HAVE BROUGHT IN SCATTERED POPS
LATER TONIGHT AS THE HRRR INDICATES MORE SHOWER ACTIVITY DEVELOPING
AS THE DISTURBANCE CURRENTLY OVER MISSOURI MOVES OVERHEAD.
OTHERWISE...DUE TO THE EXTENSIVE CLOUD COVER AND CONTINUED GUSTY
WINDS...HAVE RAISED LOW TEMPS SLIGHTLY ACROSS THE REGION TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 414 PM EDT SUN OCT 12 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A DEEPENING TROF MOVING
OFF THE ROCKIES INTO THE WRN PLAINS. DOWNSTREAM OF THE TROF...
INCREASING SOUTHERLY FLOW IS TRANSPORTING MOISTURE N UP THE
MISSISSIPPI RIVER VALLEY. THIS SHOWS UP NICELY ON VIS SATELLITE
IMAGERY AS A MASS OF CLOUDS QUICKLY SPREADING STEADILY N AT ABOUT
30KT WITH LEADING EDGE NOW INTO SE MN AND SW WI AS OF 19Z. CLOSER TO
HOME...IT`S BEEN A NICE MID OCT DAY THOUGH BREEZY IN SOME AREAS.
ADDED MOISTURE OFF LAKE MI LED TO SCT/BKN CLOUDS FOR A WHILE OVER
THE E. OTHERWISE...THERE`S BEEN ABUNDANT SUNSHINE. TEMPS HAVE RISEN
INTO THE MID 50S TO LWR 60S.
WITH A WEAK TEMP GRADIENT OVER THE WRN LAKES TONIGHT...ISENTROPIC
ASCENT IS LIMITED DESPITE CONTINUED SW FLOW. SOME WEAK DEEP LAYER
FORCING IS NOTED AS A COUPLE OF SUBTLE SHORTWAVES LIFT THRU THE WRN
GREAT LAKES. ALL IN ALL...THERE IS NOT A LOT OF SUPPORT FOR MUCH
PCPN EVEN THOUGH MOISTURE INCREASES SUBSTANTIALLY (PRECIPITABLE
WATER INCREASES FROM 50-60PCT OF NORMAL CURRENTLY TO 140-170PCT OF
NORMAL BY 12Z). UPSTREAM RADAR IMAGERY ONLY SHOWS ISOLD TO SCT
-SHRA/SPRINKLES ADVANCING NNE IN THE MOISTURE PLUME...SO A SPREAD OF
SCHC TO SPOTTY LOW CHC POPS N AND E INTO THE FCST AREA APPEARS
REASONABLE TONIGHT. INCREASING MOISTURE/CLOUDS WILL KEEP TEMPS FROM
FALLING SIGNIFICANTLY TONIGHT. 40S WILL BE THE RULE.
ON MON...SUBTLE SHORTWAVE LIFTING NE ACROSS THE AREA EARLY WILL
PROBABLY SUPPORT A CONTINUED THREAT OF ISOLD -SHRA/SPRINKLES IN THE
MORNING...THEN MUCH IF NOT ALL OF THE REST OF THE DAY WILL PROBABLY
END UP DRY UNTIL LATE IN THE AFTN. DURING THE AFTN...STRENGTHENING
OF A JET STREAK FROM MN TO JAMES BAY WILL PLACE UPPER GREAT LAKES
UNDER THE INCREASINGLY FAVORABLE RIGHT ENTRANCE...AND DOWN
BELOW...IT WILL SERVE TO STRENGTHEN LOW/MID LEVEL
FRONTOGENESIS/TIGHTENING OF THE THERMAL GRADIENT ACROSS THE AREA.
ALL MODELS SHOW A HEALTHY RIBBON OF FRONTOGENESIS BEGINNING TO
DEVELOP OVER THE UPPER MISSISSIPPI VALLEY INTO THE UPPER LAKES LATE
IN THE DAY...BUT MUCH MORE SO MON NIGHT. AS A RESULT...A DEVELOPING
AREA OF MDT TO POSSIBLY HVY RAIN SHOULD BEGIN ORGANIZING/SPREADING
NNE THRU THE MID MISSISSIPPPI VALLEY MON AFTN. LEADING EDGE OF THIS
AREA OF DEVELOPING PCPN MAY BEGIN TO REACH THE WRN AND SRN FCST AREA
VERY LATE IN THE DAY...BUT GIVEN SLOWER MODEL TRENDS IN RECENT
DAYS...WOULDN`T BE SURPRISED IF PCPN HOLDS OFF UNTIL AFTER 00Z.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 414 PM EDT SUN OCT 12 2014
TEMPERATURES WILL REMAIN NEAR NORMAL THROUGH THE EXTENDED FORECAST
WITH WET WEATHER EXPECTED THROUGHOUT THIS FORECAST PERIOD. THE
HEAVIEST RAIN IS EXPECTED MONDAY NIGHT INTO TUESDAY.
MONDAY NIGHT THROUGH WEDNESDAY...THE SURFACE LOW OVER THE MISSOURI
VALLEY WILL CONTINUE TO STRENGTHEN AS AN UPPER LEVEL LOW CLOSES OFF
JUST TO THE WEST OF THE SURFACE LOW MONDAY NIGHT. FAIRLY STRONG
ISENTROPIC UPGLIDE WILL SET UP EAST AND NORTHEAST OF THE LOW AS
PLENTY OF MOISTURE REMAINS IN PLACE. THIS WILL ALLOW RAIN TO SPREAD
INTO MUCH OF THE AREA MONDAY EVENING AND LINGER THROUGH THE
OVERNIGHT HOURS...WITH THE BETTER FOCUS BEING OVER THE CENTRAL AND
EAST WHERE THE STRONGER UPGLIDE OCCURS. AS THE LOW LIFTS NORTHWARD
AND BECOMES VERTICALLY STACKED OVERNIGHT...A DECENT FGEN BAND IS
PROGGED TO DEVELOP OVER MUCH OF THE CENTRAL AND EASTERN U.P. THIS
WILL FOCUS STRONG QCONV OVER THESE AREAS ALONG WITH THE DEEP LAYER
1000 TO 500MB RH TO LEND SUPPORT TO A STEADY...MODERATE TO
OCCASIONALLY HEAVY RAINFALL ACROSS THE AREA. PWAT VALUES ARE
EXPECTED TO BE AROUND 1 TO 1.5 INCHES ACROSS THE AREA...AGAIN
LENDING SUPPORT TO A DECENT RAINFALL. AS THE LOW WORKS SLOWLY EAST
NORTHEASTWARD INTO THE OHIO VALLEY THROUGH WEDNESDAY EXPECT THE LOW
TO WEAKEN. THE INVERTED TROUGH ASSOCIATED WITH THIS LOW WILL LINGER
OVER MUCH OF THE EASTERN U.P. THROUGH THIS TIME FRAME ALONG WITH
WEAK QCONV ALLOWING RAIN SHOWERS TO CONTINUE THROUGH THIS TIME
PERIOD. DRY AIR WILL BEGIN WORKING INTO THE NORTHWEST PORTION OF THE
U.P. TUESDAY MORNING ALLOWING SHOWERS TO TAPER OFF A BIT EARLIER
OVER THOSE AREAS.
AN ADDITIONAL CONCERN...ESPECIALLY DURING THE TUESDAY INTO TUESDAY
NIGHT TIME PERIOD IS THE POSSIBILITY FOR LARGE WAVES TO DEVELOP ON
THE TIGHTER PRESSURE GRADIENT ALONG THE INVERTED TROUGH. THESE WAVES
WOULD DEVELOP ON GUSTY NORTH TO NORTHEASTERLY WINDS....ALLOWING
WAVES TO REACH AROUND 8 FEET. THIS COULD CAUSE MINOR BEACH EROSION
ALONG THE MARQUETTE AND ALGER COUNTY SHORELINES.
WEDNESDAY NIGHT INTO THURSDAY NIGHT...MODEL TRENDS BEGIN TO DIVERGE
ON THE OVERALL TIMING AND POSITION OF THE UPPER LEVEL TROUGH AND
SURFACE LOW SHIFTING TO THE EAST OF THE UPPER PENINSULA.
CURRENTLY...IT APPEARS AS IF MOST OF THE U.P. WILL ONLY SEE LIGHT
RAIN SHOWERS THROUGH THIS TIME PERIOD AS OVERALL FORCING IS FAIRLY
WEAK AND MOISTURE IS NOT AS ABUNDANT.
FRIDAY THROUGH THE REMAINING EXTENDED...BROAD UPPER LEVEL TROUGHING
IS PROGGED TO DEVELOP OVER MUCH OF THE EASTERN U.S. ALLOWING FOR
INTERMITTENT RAIN SHOWERS TO DEVELOP ACROSS THE AREA. PINNING DOWN
SPECIFICS WILL BE A BIT TOUGH AT THIS POINT AS INCREASED RAINFALL
POTENTIAL WILL BE CLOSELY RELATED TO TIMING OF SHORTWAVES ROTATING
AROUND THE UPPER LEVEL 500MB TROUGH. AGAIN MODELS VARY SIGNIFICANTLY
ON THE FINER DETAILS AT THIS POINT THEREFORE...WILL STICK CLOSELY TO
MODEL CONSENSUS DURING THIS TIME FRAME. ON SUNDAY...MODELS ARE
TRENDING TOWARD A RIDGE BUILDING IN TO THE AREA...WHICH WOULD BEGIN
TO LEND MORE SUPPORT TO A BIT WARMER AND DRIER WEATHER.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 904 PM EDT SUN OCT 12 2014
ISOLATED SHOWERS HAVE MOVED INTO WESTERN UPPER MICHIGAN AS A WEAK
DISTURBANCE ALOFT MOVES THROUGH. EXPECT CIGS/VSBYS TO STAY VFR FOR
MUCH OF THE NIGHT HOWEVER. AS INCREASED MOISTURE OVER IOWA MOVES
NORTHWARD TONIGHT...EXPECT CIGS TO DROP TO MVFR ACROSS THE AREA LATE
TONIGHT INTO MON MORNING. IN FACT...SAW AND IWD WILL LIKELY SEE CIGS
DROP TO IFR MON AFTN AS EVEN DEEPER MOISTURE MOVES INTO THE AREA
AHEAD OF RAIN. EXPECT IFR CONDITIONS AT ALL LOCATIONS MONDAY NIGHT
INTO TUE MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 414 PM EDT SUN OCT 12 2014
SOUTHERLY WINDS AS HIGH AS 15-25KT WILL CONTINUE INTO THE EVENING
OVER ROUGHLY THE E HALF OF LAKE SUPERIOR. PRES GRADIENT THEN WEAKENS
OVERNIGHT/MON AS A LOW PRES TROF MOVES E INTO THE UPPER LAKES WHILE
LOW PRES ORGANIZES ALONG THE TROF OVER THE SOUTHERN PLAINS. THIS
WILL RESULT IN WINDS DIMINISHING OVERNIGHT AND MON. WINDS WILL BE
UNDER 10KT ACROSS THE LAKE BY MON AFTN. AS THE LOW SLOWLY LIFTS
NE...WINDS WILL BECOME N TO NE MON NIGHT AND WILL INCREASE LATE. TUE
AND TUE NIGHT...EXPECT N TO NE WINDS UP TO 20KT ON WRN LAKE SUPERIOR
AND UP TO 25KT ON ERN LAKE SUPERIOR. THE LOW WILL THEN WEAKEN AS IT
DRIFTS NE ACROSS THE GREAT LAKES REGION WED/THU...ALLOWING WINDS TO
DIMINISH. WINDS SHOULD BE UNDER 10KT BY THU. ANOTHER LOW PRES SYSTEM
TRACKING ACROSS SRN CANADA THU WILL THEN MERGE WITH THE REMNANT
GREAT LAKES LOW ON FRI IN THE VCNTY OF JAMES BAY. THIS WILL RESULT IN
INCREASING W TO NW INTO THE 15-25KT RANGE ON FRI.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...MRD
SHORT TERM...ROLFSON
LONG TERM...KEC
AVIATION...MRD
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
340 PM EDT SAT OCT 11 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 338 PM EDT SAT OCT 11 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW THAT THE PERSISTENT TROF
THAT HAS DOMINATED SE CANADA AND THE NE CONUS IS NOW LIFTING OUT AS
STRONG JET AND NEW TROF BEGIN TO PUSH INTO THE NWRN CONUS.
DOWNSTREAM RIDGE OVER THE NRN PLAINS/SCNTRL CANADA IS ALSO BEING
FORCED EASTWARD. AS A RESULT...WAA IS BEGINNING TO SPREAD INTO THE
UPPER GREAT LAKES THIS AFTN. EARLIER TODAY...QUITE A BIT OF
CU/STRATOCU DEVELOPED WITHIN 850MB THERMAL TROF THAT WAS PUSHING
ACROSS CNTRL AND ERN UPPER MI. COMBINATION OF WEAK WAA AND MIXING
OUT OF MOISTURE HAS LED TO RAPID DISSIPATION OF THESE CLOUDS FROM
THE W. AS OF 19Z...CLOUDS ARE STILL HANGING ON E OF A
MUNISING/ESCANABA LINE. EXPECT THESE CLOUDS TO CLEAR OUT OVER THE
NEXT FEW HRS.
SHORT TERM WEATHER WILL BE QUIET AS UPSTREAM RIDGE SHIFTS ACROSS THE
AREA TONIGHT AND THEN TO THE E ON SUN. THIS WILL RESULT IN GRADUALLY
STRENGTHENING SW FLOW/WAA. TONIGHT...AXIS OF STRONGEST
WAA/ISENTROPIC ASCENT IS FOCUSED WELL TO THE N TOWARD JAMES BAY
VCNTY. SO...PCPN IS NOT A CONCERN HERE. IN FACT...SKY WILL BE CLEAR.
ONLY ISSUE TONIGHT IS THE POTENTIAL FOR FOG TO DEVELOP OVER THE ERN
FCST AREA. LIGHT/CALM WIND AND GOOD RADIATIONAL COOLING AT LEAST
THRU THE EVENING WILL ALLOW TEMPS TO FALL INTO THE 30S IN THE
INTERIOR AND AS LOW AS THE UPPER 20S/LWR 30S IN THE TRADITIONAL COLD
SPOTS. WITH TEMPS FALLING PAST THE CROSSOVER TEMP AND MORE
IMPORTANTLY WITH LIGHT NEAR SFC FLOW OFF NRN LAKE MICHIGAN ADVECTING
HIGHER DWPTS INLAND OVERNIGHT...SEEMS LIKELY THAT SOME FOG WILL
DEVELOP.
DESPITE PERSISTENT SW FLOW...COLUMN REMAINS DRY ON SUNDAY. THUS...
EXPECT ABUNDANT SUNSHINE ONLY FILTERED BY SOME INCREASE IN HIGH
CLOUDS DURING THE AFTN. MIXING TO 875-850MB ON FCST SOUNDINGS YIELDS
MAX TEMPS IN THE MID 50S TO AS HIGH AS THE LWR 60S.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 338 PM EDT SAT OCT 11 2014
...WET AND UNSETTLED WEATHER IN STORE FOR EARLY NEXT WEEK...
SUNDAY NIGHT INTO MON MORNING SHOULD END UP BEING FAIRLY QUIET WITH
THE BEST MOISTURE AND LIFT ASSOCIATED WITH THE TROUGH STILL WEST OF
THE AREA. HOWEVER...AS THE FRONT AND TROUGH MOVE EAST...EXPECT AN
INCREASE OF MOISTURE AND CLOUDS...ALTHOUGH THERE WILL BE ONLY A
SLIGHT CHANCE FOR RAIN LATE CLOSE TO THE WI BORDER.
AS THE FRONTAL BOUNDARY AND ASSOCIATED UPPER TROUGH MOVES EAST
SUNDAY NIGHT...LOW PRESSURE WILL DEVELOP ALONG IT IN THE SOUTHERN
PLAINS. THIS LOW WILL MOVE NORTH/NORTHEAST MONDAY INTO TUESDAY. THE
GFS LOOKS TO BE IN BETTER AGREEMENT WITH THE ECMWF IN SHOWING A
FAIRLY SHARP AREA OF DEFORMATION AND FRONTOGENETIC CIRCULATION
DEVELOPING NEAR THE INVERTED SURFACE TROUGH EXTENDING INTO THE UPPER
GREAT LAKES MON NIGHT INTO TUESDAY. THE GFS NOW SUGGESTS THAT THE
BEST FORCING AND 850MB THERMAL PACKING WILL BE SUPPRESSED SLIGHTLY
FURTHER EAST AND SOUTH WHICH IS SIMILAR TO WHAT THE ECMWF HAS SHOWN.
AS SUCH...THE HEAVIEST PRECIPITATION WILL LIKELY BE CONFINED TO FAR
NORTHERN LOWER AND EASTERN UPPER MI. HOWEVER...AM STILL EXPECTING
MOST OF THE EASTERN 2/3 OF UPPER MICHIGAN TO SEE STEADY RAINFALL
MONDAY NIGHT INTO TUESDAY MORNING ESPECIALLY SINCE PRECIPITABLE
WATER VALUES WILL STILL BE 150-200 PCT OF NORMAL ACROSS THE EASTERN
HALF OF UPPER MICHIGAN. AS SUCH...WILL MAINTAIN CATEGORICAL POPS
ACROSS MUCH OF UPPER MICHIGAN MON NIGHT AND MAINTAIN THOSE INTO TUE
MORNING ACROSS THE EAST. WITH DRY EASTERLY FLOW INITIALLY...WILL OPT
TO HOLD OFF THE STEADY PCPN ACROSS THE FAR EAST UNTIL MON EVENING.
GUSTY NORTH WINDS TUE-TUE NIGHT WILL ALLOW FOR WAVES OF 7-9 FEET
ALONG THE SHORELINE OF MARQUETTE AND ALGER COUNTIES. GIVEN THE
RELATIVELY HIGH WATER LEVELS COMBINED WITH THE WAVE SETUP...THERE IS
THE POTENTIAL FOR SOME MINOR BEACH EROSION IN THESE AREAS.
THE UPPER LOW WILL BE QUITE SLOW TO MOVE OUT OF THE GREAT LAKES
REGION AS IT BECOMES CUT OFF FROM THE MEAN FLOW TO TH NORTH. THIS
WILL ALLOW FOR CYCLONIC FLOW ALOFT TO PERSIST ACROSS THE REGION
THROUGH WED AT LEAST. MEANWHILE...CONSIDERABLY DRIER AIR ATTEMPTS TO
MOVE IN FROM THE WEST WITH PRECIPITABLE WATER VALUES LOWERING TO
BELOW 1 INCH. WITH THIS SAID...CANNOT RULE OUT A CHANCE FOR SHOWERS
ACROSS THE EAST ON TUE NIGHT INTO WED WHERE THE BETTER MOISTURE WILL
BE. HOWEVER...DYNAMICS WILL BE FAIRLY LIMITED DESPITE CYCLONIC FLOW
ALOFT...AND INSTABILITY OFF THE LAKE WILL BE MINIMAL AT BEST DUE TO
WARM 850MB TEMPS OF AROUND +8C. WILL THEREFORE LIMIT CHC POPS ONLY
TO THE EAST TUE NIGHT INTO WED AND KEEP THE REMAINDER OF THE AREA
DRY. MAY HAVE A BETTER CHANCE FOR RAIN THURSDAY AS THE UPPER LOW
FINALLY LIFTS OUT AND THE NEXT SYSTEM APPROACHES FROM THE WEST.
HOWEVER...THE MODEL SOLUTIONS ARE CERTAINLY NOT CONSISTENT WITH THE
AMOUNT OF MOISTURE AND PCPN IN THIS PERIOD...WITH THE ECMWF BEING
MUCH MORE AGGRESSIVE THAN THE GFS OR GEM. BEHIND THIS TROUGH...850MB
TEMPS DROP TO -6C FRI NIGHT INTO SATURDAY WHICH COMBINED WITH NW PBL
FLOW SHOULD ALLOW FOR SOME LAKE EFFECT RAIN SHOWERS...AND PERHAPS A
FEW WET SNOW FLAKES SATURDAY MORNING.
OVERALL...MUCH OF THE WEEK WILL SEE TEMPS AT OR ABOVE NORMAL WITH
HIGHS EACH DAY IN THE 50S AND LOWS IN THE UPPER 30S/LOWER 40S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 141 PM EDT SAT OCT 11 2014
UNDER A DRY AIR MASS...VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW
THRU THIS FCST PERIOD. ONLY ITEM OF NOTE IS THAT CONDITIONS WILL
GET CLOSE TO LLWS CRITERIA OVERNIGHT AS LOW-LEVEL JET INCREASES.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 338 PM EDT SAT OCT 11 2014
GENERALLY QUIET MARINE WEATHER FOR THE REST OF THE WEEKEND. SOUTH TO
SOUTHWEST WINDS OF 10-20 KT WILL DEVELOP TONIGHT AHEAD OF A COLD
FRONT. THESE WINDS WILL PERSIST ON SUNDAY. SUNDAY NIGHT...LOW
PRESSURE DEVELOPS ALONG THE FRONT IN THE SOUTHERN PLAINS AND SLOWLY
MOVES INTO THE GREAT LAKES BY TUESDAY. THIS WILL ALLOW FOR SOUTH
WINDS TO GRADUALLY WEAKEN SUN NIGHT AND MONDAY...BEFORE SHIFTING TO
THE NORTH AND INCREASING TO 15 TO 25 KT ON TUE/TUE NIGHT WITH WAVES
BUILDING TO 6-9 FEET. THE LOW WEAKENS OVER THE GREAT LAKES WED WHILE
MOVING NORTHEAST...ALLOWING THE WINDS TO ALSO WEAKEN TO 10-20 KT.
SOUTH WINDS ONCE AGAIN DEVELOP ON THURSDAY AHEAD OF ANOTHER COLD
FRONT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...MRD
AVIATION...ROLFSON
MARINE...MRD
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
842 PM MDT SUN OCT 12 2014
.UPDATE...
SHORTWAVE MOVING THROUGH MONTANA IN NORTHWEST FLOW COMBINING WITH
DEEP INSTABILITY TO PRODUCE SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS ACROSS THE FORECAST AREA THIS AFTERNOON AND EVENING.
ACTIVITY HAS DECREASED SOME...BUT INSTABILITY REMAINS AND THE
SHORTWAVE HAS YET TO CLEAR THE AREA...SO RADAR WAS STILL ACTIVE
WITH SHOWERS. THE MAIN AREA WAS EAST OF A LINE FROM HARLOWTON TO
BILLINGS TO SHERIDAN. HAVE ADJUSTED POPS SOME THIS EVENING TO KEEP
ACTIVITY IN A LITTLE LONGER. ONCE THE SHORTWAVE CLEARS THE
STATE...CLOUDS SHOULD GRADUALLY DECREASE. ADJUSTED TEMPERATURES
DOWN A COUPLE OF DEGREES BASED ON HOURLY TRENDS THIS EVENING. TWH
&&
.SHORT TERM...VALID FOR MON AND TUE...
LINGERING SHORTWAVE ENERGY AND MOISTURE IN THE NNW FLOW WILL KEEP
SOME SHOWERS AND POSSIBLE THUNDERSTORMS OVER THE FORECAST
AREA...MAINLY THIS EVENING. RAP SOUNDINGS SHOWED SOME CAPE AND
STEEP LAPSE RATES OVER THE AREA THIS EVENING WHICH WILL SUPPORT A
CONTINUED CHANCE OF A FEW THUNDERSTORMS. AS UPPER RIDGING BUILDS
IN FOR MON...MODELS SHOWED A SHORTWAVE WITH SOME MOISTURE MOVING
OVER THE SW MOUNTAINS. TIME-HEIGHTS FOR THE MOUNTAINS HAD NO
UPWARD MOTION AND LIMITED MOISTURE...AND MODELS DID NOT GENERATE
ANY QPF SO WILL NOT MENTION ANY PRECIPITATION THERE AT THIS TIME.
THE UPPER RIDGE AND AN ACCOMPANYING DRY AIRMASS WILL SLIDE E
THROUGH TUE NIGHT KEEPING THE REGION DRY.
MODEL MIXING PROFILES SUPPORTED THE GOING TEMPERATURE FORECAST SO
HAVE MADE VERY LITTLE CHANGE TO INHERITED VALUES. LEE TROUGHING
MON NIGHT AND TUE NIGHT WILL BRING GUSTY WINDS TO GAP FLOW AREAS.
AT THIS POINT...GRADIENT DID NOT LOOK STRONG ENOUGH TO WARRANT ANY
HIGHLIGHTS. MON AND TUE WILL BE BREEZY TO WINDY OVER CENTRAL AND
WESTERN AREAS DUE TO GOOD MIXING. ARTHUR
.LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN...
WEDNESDAY STILL LOOKING QUITE WARM WITH INCREASED WIND AS PACIFIC
FRONT PUSHES INTO OUR WEST EITHER IN THE AFTERNOON OR EARLY
EVENING...MODELS REMAIN IN SOME DISAGREEMENT HERE. LOOKS LIKE A
COMPRESSIONAL WARMING DAY WHICH SHOULD BE WARMER THAN GUIDANCE SO
HAVE TWEAKED TEMPS UP A LITTLE MORE. COULD SEE 80F APPROACHED IN
CENTRAL OR EASTERN PARTS. OTHERWISE WE SHOULD SEE A BRIEF PERIOD
OF SYNOPTIC ASCENT INTO OUR WEST DUE TO PACIFIC SHORTWAVE BY
AFTERNOON. GIVEN THIS IS PEAK HEATING AND WE SHOULD SEE SOME
DIURNAL INSTABILITY ESPECIALLY AS HEIGHTS BEGIN TO FALL...HAVE
EXPANDED SLIGHT POPS TO INCLUDE THE LIVINGSTON TO HARLOWTON AREAS
WEDNESDAY AFTERNOON. FAST-MOVING ENERGY MAY BRING A FEW LIGHT
SHOWERS TO OUR FAR NORTH IN THE EVENING...THEN DESCENT SPREADS IN
QUICKLY THROUGH THE NIGHT PUTTING AN END TO ANY PCPN CHANCES. MAIN
IMPACT FROM THIS WAVE WILL BE INCREASED WESTERLY WINDS FROM
WEDNESDAY AFTERNOON THROUGH THURSDAY.
MOSTLY QUIET WEATHER SHOULD DOMINATE OUR REGION THURSDAY THROUGH
NEXT WEEKEND...WITH TEMPS STAYING ABOVE NORMAL AND IN THE 60S FOR
HIGHS...AND MAYBE BACK NEAR 70F BY NEXT WEEKEND. ECMWF/GFS SUGGEST
A WEAK PACIFIC SHORTWAVE ON SATURDAY...BUT WITH LITTLE MOISTURE TO
WORK WITH. WILL KEEP FORECAST DRY.
LOOKING FURTHER AHEAD...MODELS IN GOOD AGREEMENT SHOWING A RETURN
TO STRONG RIDGING OVER THE HIGH PLAINS EARLY THE FOLLOWING
WEEK...WITH A PERSISTENT LOW HEIGHT ANOMALY IN THE NORTH PACIFIC.
AT THIS TIME THERE IS NO SIGN OF A PATTERN SHIFT TO COLDER
CONDITIONS BUT WILL NEED TO CONTINUE TO MONITOR THE TROPICAL
PACIFIC AS IT REMAINS ACTIVE. JKL
&&
.AVIATION...
SCATTERED SHOWERS AND THUNDERSTORMS CONTINUE ACROSS WESTERN
ROUTES...EXTENDING NORTHWEST FROM NEAR KSHR TOWARD KLWT ...WITH
POTENTIAL SNOW SHOWERS IN THE THE HIGHER TERRAIN. VFR CONDITIONS
PREVAIL...BUT LOCALIZED MVFR CONDITIONS ARE POSSIBLE MAINLY NEAR
THE FOOTHILLS...AND THE MOUNTAINS WILL BE FREQUENTLY OBSCURED.
ACTIVITY WILL CONTINUE TO DIMINISH OVERNIGHT. GUSTY WINDS HAVE
TAPER OFF ACROSS THE REGION THIS EVENING...BUT SOUTHWEST WINDS
WILL DEVELOP AND INCREASE LATE TONIGHT AND MONDAY ACROSS THE
WESTERN FOOTHILL...INCLUDING KLVM. AAG
&&
.PRELIMINARY POINT TEMP/POPS...
MON TUE WED THU FRI SAT SUN
-----------------------------------------------------------
BIL 036/064 045/076 050/075 045/062 036/062 043/069 044/067
20/B 00/U 00/B 10/N 00/U 11/B 11/U
LVM 031/064 041/074 046/071 040/058 034/063 039/066 041/064
20/N 00/N 02/W 11/N 11/B 11/B 11/B
HDN 035/066 039/078 045/077 042/065 034/065 039/071 041/069
20/U 00/U 00/B 10/U 00/U 11/B 11/U
MLS 035/065 039/078 045/078 044/063 035/062 036/067 041/066
20/B 00/U 00/U 20/N 00/U 11/B 11/B
4BQ 034/063 039/079 046/078 044/063 034/062 036/067 040/067
20/U 00/U 00/U 00/N 00/U 01/U 11/B
BHK 032/062 036/073 043/076 043/060 031/057 032/061 036/062
20/U 00/U 00/U 10/N 00/U 01/B 11/B
SHR 030/061 036/076 043/079 039/062 030/063 036/069 040/066
30/U 00/U 00/B 00/U 00/U 01/B 11/U
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
917 AM MDT SAT OCT 11 2014
.UPDATE...
MORNING SURFACE ANALYSIS SHOWED COLD FRONT FROM JUST N OF ID
THROUGH S ALBERTA THEN NE INTO W CENTRAL SASKATCHEWAN. MODELS HAD
A GOOD HANDLE ON FRONTAL PLACEMENT. SOME ECHO WAS SHOWING UP ON
RADAR OVER W MT. CHECK OF THE WEBCAMS SHOWED THIS WAS ALTOCUMULUS
AND MOUNTAINS DID NOT APPEAR TO BE AFFECTED BY ANY SHOWERS. THERE
WERE A COUPLE OF SHOWERS OVER SE MT EARLIER THIS MORNING DUE TO A
SHORTWAVE...SEEN IN WATER VAPOR IMAGERY...BUT THESE HAVE
DISSIPATED. THE WAVE WAS MOVING E AND WOULD NOT EXPECT ANY MORE
SHOWER DEVELOPMENT OVER SE MT AS IT MOVES OUT. MOISTURE WILL
DEEPEN OVER THE MOUNTAINS AND NEARBY AREAS LATE THIS AFTERNOON AS
VORTICITY INCREASES OVER THESE AREAS AND THE FRONT SINKS SE. HRRR
WAS TOO FAST IN PRODUCING PRECIPITATION OVER THE AREA THIS
MORNING...BUT OTHER MODELS LOOKED MORE REASONABLE. RAP BUFKIT
SOUNDINGS SHOWED VERY DRY AIR OVER E MT/KSHR THIS AFTERNOON SO
HAVE REMOVED POPS FROM THESE AREAS AND KEPT POPS FROM KBIL AND THE
NE BIG HORNS W. THESE POPS WERE IN LINE WITH QPF FROM NEW WRF AND
GFS. KEPT THUNDER OUT OF THE FORECAST BASED ON WRF NOT SHOWING
MUCH INSTABILITY. CHANCES FOR PRECIPITATION WILL INCREASE TONIGHT
OVER THE AREA AS THE SYSTEM MOVES THROUGH THE REGION.
TEMPERATURES WERE IN GOOD SHAPE BASED ON MIXING TO 700 MB.
INCREASED WINDS A BIT THROUGH THE DAY BASED ON EXPECTED MIXING. IT
WILL BE A BREEZY AND MILD DAY ACROSS MUCH OF THE AREA. INCREASED
CLOUD COVER THROUGH 18Z OVER WESTERN AREAS DUE TO THE MID LEVEL
CLOUDS. ARTHUR
&&
.SHORT TERM...VALID FOR TDY AND SUN...
A STRONG PACIFIC JET STREAM WILL NOSE INTO THE AREA
TODAY...GENERATING DOWNSLOPE WARMING THAT WILL PUSH TEMPERATURES
INTO THE 65 TO 75 DEGREE RANGE THIS AFTERNOON. THIS DOWNSLOPE FLOW
WILL ALSO PREVENT PRECIPITATON FOR MOST OF THE DAY DESPITE A
STRONG INFLUX OF PACIFIC MOISTURE OVER THE AREA...BUT A
SIGNIFICANT INCREASE IN CLOUD COVER IS EXPECTED THIS AFTERNOON.
BY LATE IN THE DAY THE JET WILL DEVELOP A PRONOUNCED KINK
SOUTHWARD AS A STRONG DISTURBANCE PUNCHES SOUTHEAST OUT OF
BRITISH COLUMBIA. THIS SYSTEM WILL ALLOW THE SURFACE TROF OVER THE
AREA TO MORPH INTO A COLD FRONT AS COOLER AIR GETS DRAGGED SOUTH
OUT OF CANADA ALONG WITH DYNAMIC COOLING AS THE UPPER PATTERN
BECOMES DIFFLUENT AND QG FORCING RAPIDLY INCREASES. WITH STRONG
DYNAMICS ALOFT AND SURFACE TO 700MB FRONTOGENESIS BUILDING OVER
THE AREA PRECIPITATION CHANCES WILL INCREASE THROUGH THE NIGHT
INTO SUNDAY MORNING. GIVEN THE STRONG DYNAMICS THE MODELS ARE
SHOWING WOULD EXPECT HIGH PRECIPITATION CHANCES. HOWEVER THE LOW
LEVEL PATTERN DEVELOPS IN A WAY THAT KEEPS LOW LEVEL WINDS IN A
GUSTY WEST TO NORTHWEST DIRECTION RESULTING IN DOWNSLOPE DRYING
THAT WILL KEEP POPS LOWER THAN FORCING WOULD SUGGEST. IT WILL ALSO
TAKE A WHILE FOR THE LOWER ATMOSPHERE TO MOISTEN UP ENOUGH FOR
PRECIPITATION TO REACH THE GROUND. BEST CHANCES FOR PRECIPITATION
WILL BE GENERALLY SOUTH OF A LIVINGSTON TO BILLINGS TO EKALAKA
LINE LATE TONIGHT INTO SUNDAY MORNING...WITH SCATTERED SHOWERS OFF
AND ON OVERNIGHT TO THE NORTH OF THE LINE. OVERALL PRECIPITATION
AMOUNTS LOOK FAIRLY LIGHT AND WILL RANGE FROM A FEW HUNDREDTHS OF
AN INCH OVER NORTHERN AND EASTERN AREAS TO OVER A QUARTER OF AN
INCH IN SOME SOUTHERN FOOTHILLS LOCATIONS THAT ARE FAVORABLE TO
NORTHWEST WINDS. 700MB TEMPERATURES WILL DROP ENOUGH FOR SNOW TO
DEVELOP ABOVE 7000 FEET LATE THIS EVENING. EXPECT 2 TO 4 INCHES OF
SNOW ABOVE THIS ELEVATION. THIS WILL IMPACT TRAVEL OVER THE
BEARTOOTH PASS TONIGHT INTO TOMORROW MORNING.
FOR SUNDAY...MOST OF THE UPPER DYNAMICS SHIFTS SOUTH OF THE AREA
IN THE MORNING HOURS. THIS LEAVES THE AREA UNDER THE MEAN TROF FOR
THE AFTERNOON. INSTABILITY WILL BE ENOUGH TO PRODUCE SCATTERED
SHOWERS INTO THE EVENING HOURS...WITH SOME MORE PERSISTENT BANDING
POSSIBLE OFF THE CRAZY...SNOWY AND LITTLE BELT MOUNTAINS.
NORTHWEST WINDS WILL BE GUSTY THROUGH THE DAY MAKING TEMPERATURES
FEEL COLDER THAN THE 50S AND LOWER 60S EXPECTED FOR HIGH
TEMPERATURES. WINDS AND PRECIPITATION WILL DIMINISH SUNDAY
EVENING. CLEARING WILL ALLOW FOR TEMPERATURES IN THE 30S WITH SOME
SUB- FREEZING READINGS POSSIBLE IN THE LOWER ELEVATIONS...AND
LOWER 20S IN THE MOUNTAINS. CHAMBERS
.LONG TERM...VALID FOR MON...TUE...WED...THU...FRI...
NORTHWESTERLY FLOW ALOFT ON MONDAY WILL KEEP TEMPERATURES COOL BUT
UPPER LEVEL RIDGING MOVING INTO THE AREA WILL START DRYING OUT THE
AIRMASS. RIDGE AXIS CROSSES THE STATE TUESDAY WITH LOW PRESSURE
FORMING OVER ALBERTA AND SASKATCHEWAN SUPPORTING WEAK DOWNSLOPE
FLOW. THIS WILL BRING A RETURN TO WARM TEMPERATURES IN THE 70S
WHICH WILL PERSIST INTO WEDNESDAY.
MODELS AGREE THAT A TRANSITION OCCURS ON THURSDAY AS A TROUGH AXIS
CROSSES MONTANA INTO THE DAKOTAS BUT THIS FEATURE IS LOOKING
WEAKER WITH EACH MODEL RUN. THE ASSOCIATED COOL DOWN AND CHANCES
FOR PRECIPITATION ARE LOOKING LESS AND LESS SO RAISED TEMPERATURES AND
LOWERED POPS IN THE LATER PART OF THE EXTENDED. BORSUM
&&
.AVIATION...
CLOUDS WILL BE INCREASING THROUGH THE DAY WITH SOME MOUNTAIN
OBSCURATIONS POSSIBLE BY LATE AFTERNOON. SCATTERED SHOWERS WILL
MOVE INTO THE AREA FROM NORTHWEST TO SOUTHEAST IN THE LATE
AFTERNOON AND EVENING...WITH LOCAL MVFR CONDITIONS POSSIBLE AFTER
00Z OVER THE MOUNTAINS AND FOOTHILLS. EXPECT GUSTY WEST WINDS
THROUGH THE DAY FOR WESTERN AREAS...THEN W-NW WINDS ACROSS THE
AREA TONIGHT BEHIND A COLD FRONTAL PASSAGE. JKL
&&
.PRELIMINARY POINT TEMP/POPS...
TDY SUN MON TUE WED THU FRI
-------------------------------------------------------
BIL 073 046/056 036/062 045/072 050/073 043/061 035/060
2/W 55/W 20/U 00/U 01/U 11/N 11/U
LVM 068 040/051 032/061 042/071 047/068 039/057 033/059
2/W 56/W 20/B 00/U 11/B 21/N 11/B
HDN 075 047/059 037/064 040/075 045/075 041/064 035/063
1/B 55/W 20/U 00/U 00/U 11/N 11/U
MLS 075 047/062 037/063 040/074 045/074 043/063 034/062
1/B 33/W 10/U 00/U 00/U 21/N 11/U
4BQ 075 047/056 036/061 039/073 046/076 042/062 034/061
1/B 66/W 10/U 00/U 00/U 11/N 11/U
BHK 074 044/058 035/059 035/070 044/073 041/060 031/055
1/B 33/W 10/U 00/U 00/U 11/N 11/U
SHR 072 042/050 032/059 036/074 042/074 037/060 031/061
1/B 66/W 20/U 00/U 00/U 11/B 11/U
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
727 PM CDT SUN OCT 12 2014
.UPDATE...
ISSUED AT 725 PM CDT SUN OCT 12 2014
UPDATED THE FORECAST THIS EVENING TO LOWER CHANCES OF PRECIP IN
SOUTHWESTERN PORTIONS OF OUR NEBRASKA COUNTIES AS MUCH OF THE RAIN
HAS CLEARED OFF TO THE EAST.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 224 PM CDT SUN OCT 12 2014
TONIGHT THROUGH MONDAY...MAIN ISSUES ARE PRECIPITATION ONGOING...
AND STRONG WINDS MONDAY.
THE AS ADVERTISED STRONG UPPER LEVEL SYSTEM CONTINUES TO BE ON TRACK
FOR RAPID STRENGTHENING AND CYCLOGENISIS ACROSS THE SOUTHERN PLAINS
THE NEXT 18-24 HOURS. INITIAL COLD FRONTAL SURGE IS CURRENTLY ACROSS
WESTERN NEBRASKA...APPROACHING THEDFORD AND NORTH PLATTE. THIS SEEMS
A BIT QUICKER GIVEN THE TENDENCY THE LAST DAY OR SO FOR THE MODELS
TO BE A BIT SLOWER OVERALL WITH DEVELOPING FEATURES. INITIAL ROUND
OF DIFFERENTIAL VORTICITY ADVECTION AND MID LEVEL WARM ADVECTION HAS
SPARKED A SLOW TO MOVE AREA OF SHOWERS AND ISOLATED THUNDERSTORMS
WHICH BEGAN FIRST THING THIS MORNING. COUPLE AUTOMATED WEATHER
STATIONS DID REPORT ABOUT ONE-QUARTER INCH OF RAIN IN PHILLIPS COUNTY
KANSAS...AND THIS HAS BEEN A STEADY EVENT ALTHOUGH THE LOW LEVELS
ARE VERY DRY WITH NEAR 40 DEWPOINTS OVER THE NORTHEAST FORECAST
AREA. RELYING ON THE HRRR AND ITS HANDLING...THIS PRECIPITATION
GRADUALLY MOVES NORTHEAST ACROSS THE FORECAST AREA THE NEXT FEW
HOURS...AND LOSES SOME STEAM AS IT MOVES THROUGH THE DRY AIR. THAT
IS TREND FOLLOWED IN THE FORECAST...ALONG WITH AN ISOLATED STORM
OR TWO.
MAIN PRECIPITATION CHANCE COMES LATER TONIGHT. AS THE COLD FRONT
FIRES UP THE DEEPENING LOW WITH INCREASING BAROCLINICITY...A CLASSIC
DEFORMATION AXIS SETS UP ON THE NORTHWEST SIDE OF THE MAIN UPPER
LEVEL LOW. SOME 12Z MODELS /WRF-NAM/ NOW HOLD THAT AXIS FURTHER
NORTHWEST AND IMPLY A STEADY RAIN IS POSSIBLE EVEN IN THE HASTINGS
AREA. OTHER MODELS CONTINUE TO OFFER THE RAIN JUST A BIT FURTHER
SOUTHEAST...BUT SOLIDLY ACROSS NORTH CENTRAL KANSAS...AND SOUTHEAST
OF A YORK TO RED CLOUD LINE LATE TONIGHT AND EARLY MONDAY. THAT IS
WERE THE HIGHEST PRECIPITATION CHANCES HAVE BEEN...AND CONTINUE TO
BE TONIGHT AND EARLY MONDAY. IT IS IMPORTANT TO NOTE...THERE WILL
BE AN EXTREMELY SHARP CUTOFF FROM RAIN TO NO-RAIN PROBABLY SOUTHEAST
OF HASTINGS. IN THE RAIN AREA...ITS A SOLID CHILLY RAIN...BUT WILL
END ABOUT AS ABRUPTLY AS IT CAN AT SOME POINT ON ITS NORTHWEST EDGE.
RAIN AMOUNTS COULD BE DECENT IN THIS BAND...ALTHOUGH ITS HARD TO
SELL OUT GIVEN THE EXACT BAND LOCATION WILL NOT BE KNOW FOR SEVERAL
HOURS. THE RAIN WRAPS UP BY MIDDAY IN THE EASTERN FORECAST AREA...
AND CLEARING SKIES WILL PULL EAST NICELY BY AFTERNOON.
THE OTHER MAIN STORY ON MONDAY IS THE WIND. DEEPENING LOW...GOOD
MIXING...NICE UNI-DIRECTIONAL SHEAR...ALL POINT TO STRONG MOMENTUM
TRANSFER DOWNWARD OF STRONG WINDS. GUST POTENTIAL IN THE 50 MPH IS
POSSIBLE...ESPECIALLY IN THE LATE MORNING/MIDDAY TIMFRAME ACROSS
FAR SOUTHERN NEBRASKA AND NORTH CENTRAL KANSAS IN THE LATE MORNING
AND MIDDAY AREAS. HOISTED A WIND ADVISORY FOR THE DAY MONDAY. IT MAY
NOT BE A SLAM DUNK IN THE NORTHEAST AREAS...AND BEGINNING AND ENDING
TIMES ARE NOT WELL ALIGNED ACROSS THE FORECAST AREA...BUT CONSENSUS
AMONG US AND SEVERAL KANSAS OFFICES WAS A WIND ADVISORY. ADVISORY
STARTS AT 7 AM AND ENDS AT 7 PM MONDAY FOR ALL AREAS TO MAKE THINGS
EASY.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 224 PM CDT SUN OCT 12 2014
MONDAY NIGHT THROUGH SUNDAY.
STARTING OUT MONDAY NIGHT...THE PATTERN ALOFT WILL BE AMPLIFIED WITH
AN UPPER TROUGH MOVING INTO THE PACIFIC NW...RIDGING OVER THE
ROCKIES...A TROUGH IN THE INTERIOR CONUS ACROSS THE PLAINS GENERALLY
ALONG THE MO RIVER...AND UPPER RIDGING IN THE ATLANTIC OCEAN. IN A
TIGHT SURFACE PRESSURE GRADIENT WITH THE SFC LOW IN IOWA...NORTH
WINDS WILL REMAIN STRONG/GUST FOR A COUPLE OF HOURS DURING THE
EVENING BEFORE DECOUPLING.
THE UPPER TROUGH CONTINUES TO EXIT TO THE EAST MONDAY NIGHT AND
TUESDAY WITH RISING HEIGHTS AND WARMER AIR WORKING ONTO THE PLAINS
AS THE UPPER RIDGE AXIS OVER THE ROCKIES REACHES THE HIGH PLAINS. THE
LLVL PRESSURE GRADIENT WILL NOT BE AS TIGHT ON TUESDAY HOWEVER
FORECAST SOUNDING INDICATE MIXING TO H85 WITH WINDS AT THE TOP OF
THE LAYER AROUND 25KTS THRU THE MORNING AND AROUND 20KTS IN THE AFTN
SO DO EXPECT SOME BREEZY NORTH WINDS AT TIMES ESPECIALLY FOR THE
FIRST PART OF THE DAY. DAYTIME TEMPERATURES ARE STILL LOOKING
SEASONAL WITH HIGHS AVERAGING IN THE MID 60S.
BOTH MONDAY NIGHT AND TUESDAY NIGHTS LOOK TO BE THE COLDEST OF THE
EXTENDED PERIODS. SFC DPS DROP TO THE LOW/MID 30S AND LOW TEMPS IN
THE 30S ARE POSSIBLE...ESPECIALLY ACROSS PORTIONS OF SOUTH CENTRAL
NEBRASKA. WIND SPEEDS BE LIGHTER TUESDAY NIGHT VS MONDAY NIGHT
UNDER INFLUENCE OF SURFACE RIDGE AND FROST DEVELOPMENT MAY OCCUR.
SINCE THE LOWER TEMPS WILL MATERIALIZE IN AREAS WHICH ALREADY
FROZE...WILL NOT INCLUDE FROST MENTION IN GRIDS/HWO ATTM.
THE MIDDLE OF THE WEEK WILL SEE THE UPPER RIDGE DEAMPLIFY AS IT
MIGRATES ONTO THE PLAINS DUE TO ENERGY TRANSLATING FM THE PACIFIC NW
ACROSS THE US/CANADIAN BORDER. AHEAD OF AN APPROACHING COLD
FRONT...TEMPS WILL MAKE A RUN NEAR OR INTO THE 70S ON WEDNESDAY.
THE COLD FRONTAL BOUNDARY PUSHES SOUTH EARLY THURSDAY...WITH OVERALL
COOLING BEHIND THE FRONT NEGLIGIBLE AND TEMPS GRADUALLY RETURN
CLOSER TO SEASONAL NORMS. THE NORTHERN CONUS SYSTEM DEEPENS IN
ONTARIO FOR THE LATTER PART OF THE WORWEEK WITH FLOW ACROSS THE
PLAINS TRANSITIONING MORE NORTHWESTERLY FOR A TIME. THERE ARE SOME
MODEL DIFFERENCES IN HANDLING THIS TROUGH AS WELL AS THE WESTERN
RIDGE AND DID NOT DEVIATE FROM EXTENDED INIT. FOR THE MOST PART THE
WEEKEND IS LOOKING MAINLY DRY ALTHOUGH MODELS HINT AS SOME LIGHT
PCPN DEVELOPMENT ON SUNDAY BUT THIS IS NOT CLEAR CUT. MAINLY DRY
CONDITIONS AND FAIRLY SEASONAL TEMPS STILL LOOK REASONABLE FOR THE
EXTENDED FORECAST PERIODS.
&&
.AVIATION...(FOR THE 00Z KGRI/KEAR TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 658 PM CDT SUN OCT 12 2014
MOSTLY VFR CONDITIONS ARE EXPECTED...ALTHOUGH THERE COULD BE SOME
MVFR CEILINGS HANGING AROUND AS MUCH OF THE RAIN CLEARS OFF TO THE
EAST. WIND WILL BE AN ISSUE FOR MONDAY DUE TO A STRONG SURFACE
PRESSURE GRADIENT. EXPECT CLEARING AS A LOW IN THE SOUTHERN PLAINS
HEADS EAST.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...WIND ADVISORY FROM 7 AM TO 7 PM CDT MONDAY FOR NEZ039>041-
046>049-060>064-072>077-082>087.
KS...WIND ADVISORY FROM 7 AM TO 7 PM CDT MONDAY FOR KSZ005>007-
017>019.
&&
$$
UPDATE...HEINLEIN
SHORT TERM...NOAA/NWS/MORITZ
LONG TERM...FAY
AVIATION...HEINLEIN
AREA FORECAST DISCUSSION
NWS HASTINGS NE
700 PM CDT SUN OCT 12 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 224 PM CDT SUN OCT 12 2014
TONIGHT THROUGH MONDAY...MAIN ISSUES ARE PRECIPITATION ONGOING...
AND STRONG WINDS MONDAY.
THE AS ADVERTISED STRONG UPPER LEVEL SYSTEM CONTINUES TO BE ON TRACK
FOR RAPID STRENGTHENING AND CYCLOGENISIS ACROSS THE SOUTHERN PLAINS
THE NEXT 18-24 HOURS. INITIAL COLD FRONTAL SURGE IS CURRENTLY ACROSS
WESTERN NEBRASKA...APPROACHING THEDFORD AND NORTH PLATTE. THIS SEEMS
A BIT QUICKER GIVEN THE TENDENCY THE LAST DAY OR SO FOR THE MODELS
TO BE A BIT SLOWER OVERALL WITH DEVELOPING FEATURES. INITIAL ROUND
OF DIFFERENTIAL VORTICITY ADVECTION AND MID LEVEL WARM ADVECTION HAS
SPARKED A SLOW TO MOVE AREA OF SHOWERS AND ISOLATED THUNDERSTORMS
WHICH BEGAN FIRST THING THIS MORNING. COUPLE AUTOMATED WEATHER
STATIONS DID REPORT ABOUT ONE-QUARTER INCH OF RAIN IN PHILLIPS COUNTY
KANSAS...AND THIS HAS BEEN A STEADY EVENT ALTHOUGH THE LOW LEVELS
ARE VERY DRY WITH NEAR 40 DEWPOINTS OVER THE NORTHEAST FORECAST
AREA. RELYING ON THE HRRR AND ITS HANDLING...THIS PRECIPITATION
GRADUALLY MOVES NORTHEAST ACROSS THE FORECAST AREA THE NEXT FEW
HOURS...AND LOSES SOME STEAM AS IT MOVES THROUGH THE DRY AIR. THAT
IS TREND FOLLOWED IN THE FORECAST...ALONG WITH AN ISOLATED STORM
OR TWO.
MAIN PRECIPITATION CHANCE COMES LATER TONIGHT. AS THE COLD FRONT
FIRES UP THE DEEPENING LOW WITH INCREASING BAROCLINICITY...A CLASSIC
DEFORMATION AXIS SETS UP ON THE NORTHWEST SIDE OF THE MAIN UPPER
LEVEL LOW. SOME 12Z MODELS /WRF-NAM/ NOW HOLD THAT AXIS FURTHER
NORTHWEST AND IMPLY A STEADY RAIN IS POSSIBLE EVEN IN THE HASTINGS
AREA. OTHER MODELS CONTINUE TO OFFER THE RAIN JUST A BIT FURTHER
SOUTHEAST...BUT SOLIDLY ACROSS NORTH CENTRAL KANSAS...AND SOUTHEAST
OF A YORK TO RED CLOUD LINE LATE TONIGHT AND EARLY MONDAY. THAT IS
WERE THE HIGHEST PRECIPITATION CHANCES HAVE BEEN...AND CONTINUE TO
BE TONIGHT AND EARLY MONDAY. IT IS IMPORTANT TO NOTE...THERE WILL
BE AN EXTREMELY SHARP CUTOFF FROM RAIN TO NO-RAIN PROBABLY SOUTHEAST
OF HASTINGS. IN THE RAIN AREA...ITS A SOLID CHILLY RAIN...BUT WILL
END ABOUT AS ABRUPTLY AS IT CAN AT SOME POINT ON ITS NORTHWEST EDGE.
RAIN AMOUNTS COULD BE DECENT IN THIS BAND...ALTHOUGH ITS HARD TO
SELL OUT GIVEN THE EXACT BAND LOCATION WILL NOT BE KNOW FOR SEVERAL
HOURS. THE RAIN WRAPS UP BY MIDDAY IN THE EASTERN FORECAST AREA...
AND CLEARING SKIES WILL PULL EAST NICELY BY AFTERNOON.
THE OTHER MAIN STORY ON MONDAY IS THE WIND. DEEPENING LOW...GOOD
MIXING...NICE UNI-DIRECTIONAL SHEAR...ALL POINT TO STRONG MOMENTUM
TRANSFER DOWNWARD OF STRONG WINDS. GUST POTENTIAL IN THE 50 MPH IS
POSSIBLE...ESPECIALLY IN THE LATE MORNING/MIDDAY TIMFRAME ACROSS
FAR SOUTHERN NEBRASKA AND NORTH CENTRAL KANSAS IN THE LATE MORNING
AND MIDDAY AREAS. HOISTED A WIND ADVISORY FOR THE DAY MONDAY. IT MAY
NOT BE A SLAM DUNK IN THE NORTHEAST AREAS...AND BEGINNING AND ENDING
TIMES ARE NOT WELL ALIGNED ACROSS THE FORECAST AREA...BUT CONSENSUS
AMONG US AND SEVERAL KANSAS OFFICES WAS A WIND ADVISORY. ADVISORY
STARTS AT 7 AM AND ENDS AT 7 PM MONDAY FOR ALL AREAS TO MAKE THINGS
EASY.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 224 PM CDT SUN OCT 12 2014
MONDAY NIGHT THROUGH SUNDAY.
STARTING OUT MONDAY NIGHT...THE PATTERN ALOFT WILL BE AMPLIFIED WITH
AN UPPER TROUGH MOVING INTO THE PACIFIC NW...RIDGING OVER THE
ROCKIES...A TROUGH IN THE INTERIOR CONUS ACROSS THE PLAINS GENERALLY
ALONG THE MO RIVER...AND UPPER RIDGING IN THE ATLANTIC OCEAN. IN A
TIGHT SURFACE PRESSURE GRADIENT WITH THE SFC LOW IN IOWA...NORTH
WINDS WILL REMAIN STRONG/GUST FOR A COUPLE OF HOURS DURING THE
EVENING BEFORE DECOUPLING.
THE UPPER TROUGH CONTINUES TO EXIT TO THE EAST MONDAY NIGHT AND
TUESDAY WITH RISING HEIGHTS AND WARMER AIR WORKING ONTO THE PLAINS
AS THE UPPER RIDGE AXIS OVER THE ROCKIES REACHES THE HIGH PLAINS. THE
LLVL PRESSURE GRADIENT WILL NOT BE AS TIGHT ON TUESDAY HOWEVER
FORECAST SOUNDING INDICATE MIXING TO H85 WITH WINDS AT THE TOP OF
THE LAYER AROUND 25KTS THRU THE MORNING AND AROUND 20KTS IN THE AFTN
SO DO EXPECT SOME BREEZY NORTH WINDS AT TIMES ESPECIALLY FOR THE
FIRST PART OF THE DAY. DAYTIME TEMPERATURES ARE STILL LOOKING
SEASONAL WITH HIGHS AVERAGING IN THE MID 60S.
BOTH MONDAY NIGHT AND TUESDAY NIGHTS LOOK TO BE THE COLDEST OF THE
EXTENDED PERIODS. SFC DPS DROP TO THE LOW/MID 30S AND LOW TEMPS IN
THE 30S ARE POSSIBLE...ESPECIALLY ACROSS PORTIONS OF SOUTH CENTRAL
NEBRASKA. WIND SPEEDS BE LIGHTER TUESDAY NIGHT VS MONDAY NIGHT
UNDER INFLUENCE OF SURFACE RIDGE AND FROST DEVELOPMENT MAY OCCUR.
SINCE THE LOWER TEMPS WILL MATERIALIZE IN AREAS WHICH ALREADY
FROZE...WILL NOT INCLUDE FROST MENTION IN GRIDS/HWO ATTM.
THE MIDDLE OF THE WEEK WILL SEE THE UPPER RIDGE DEAMPLIFY AS IT
MIGRATES ONTO THE PLAINS DUE TO ENERGY TRANSLATING FM THE PACIFIC NW
ACROSS THE US/CANADIAN BORDER. AHEAD OF AN APPROACHING COLD
FRONT...TEMPS WILL MAKE A RUN NEAR OR INTO THE 70S ON WEDNESDAY.
THE COLD FRONTAL BOUNDARY PUSHES SOUTH EARLY THURSDAY...WITH OVERALL
COOLING BEHIND THE FRONT NEGLIGIBLE AND TEMPS GRADUALLY RETURN
CLOSER TO SEASONAL NORMS. THE NORTHERN CONUS SYSTEM DEEPENS IN
ONTARIO FOR THE LATTER PART OF THE WORWEEK WITH FLOW ACROSS THE
PLAINS TRANSITIONING MORE NORTHWESTERLY FOR A TIME. THERE ARE SOME
MODEL DIFFERENCES IN HANDLING THIS TROUGH AS WELL AS THE WESTERN
RIDGE AND DID NOT DEVIATE FROM EXTENDED INIT. FOR THE MOST PART THE
WEEKEND IS LOOKING MAINLY DRY ALTHOUGH MODELS HINT AS SOME LIGHT
PCPN DEVELOPMENT ON SUNDAY BUT THIS IS NOT CLEAR CUT. MAINLY DRY
CONDITIONS AND FAIRLY SEASONAL TEMPS STILL LOOK REASONABLE FOR THE
EXTENDED FORECAST PERIODS.
&&
.AVIATION...(FOR THE 00Z KGRI/KEAR TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 658 PM CDT SUN OCT 12 2014
MOSTLY VFR CONDITIONS ARE EXPECTED...ALTHOUGH THERE COULD BE SOME
MVFR CEILINGS HANGING AROUND AS MUCH OF THE RAIN CLEARS OFF TO THE
EAST. WIND WILL BE AN ISSUE FOR MONDAY DUE TO A STRONG SURFACE
PRESSURE GRADIENT. EXPECT CLEARING AS A LOW IN THE SOUTHERN PLAINS
HEADS EAST.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...WIND ADVISORY FROM 7 AM TO 7 PM CDT MONDAY FOR NEZ039>041-
046>049-060>064-072>077-082>087.
KS...WIND ADVISORY FROM 7 AM TO 7 PM CDT MONDAY FOR KSZ005>007-
017>019.
&&
$$
SHORT TERM...NOAA/NWS/MORITZ
LONG TERM...FAY
AVIATION...HEINLEIN
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
648 PM CDT SUN OCT 12 2014
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY)
ISSUED AT 154 PM CDT SUN OCT 12 2014
MAIN FORECAST CONCERN WILL BE TIMING AND EXTENT OF PRECIP
ASSOCIATED WITH SYSTEM MOVING ACROSS THE SOUTHERN PLAINS
TONIGHT THROUGH TUESDAY.
RADAR SHOWING AREA OF SHOWERS AND THUNDERSTORMS OVER SOUTH CENTRAL
NEBRASKA LIFTING TOWARD NORTHEAST NEBRASKA AT 19Z. ALTHOUGH 12Z
MODELS SHOW SOME RAIN MOVING ACROSS THE AREA TONIGHT AND MONDAY
THE BETTER CHANCE OF SIGNIFICANT RAINFALL LOOKS TO STAY SOUTH AND
EAST OF THE CWA. LATEST RAP AND HRRR ALSO SHOW THIS TREND THROUGH
THE EVENING WITH BETTER FORCING AND INSTABILITY LOCATED TO THE
SOUTH.
HAVE ADJUSTED WEATHER DURING THIS TIME BY REMOVING MODERATE
CATEGORY OF RAIN AND KEPT JUST LIGHT SHOWERS TO REFLECT THIS
LATEST MODEL SOLUTION. SOME ISOLATED THUNDER IS POSSIBLE THIS
EVENING ALONG THE SOUTHEAST BORDER WHERE SOME INSTABILITY IS
INDICATED THROUGH 06Z. PRIMARY IMPACT WITH THIS SYSTEM LOOKS TO BE
WIND BEHIND THE FRONT AS IT MOVES THROUGH THE AREA. INCREASING
NORTH WINDS ARE EXPECTED TO MOVE INTO WESTERN PARTS OF THE AREA
AFTER 06Z TONIGHT THEN SPREAD EAST ACROSS THE REST OF THE CWA ON
MONDAY. AT THIS TIME IT APPEARS THE STRONGEST WINDS WILL STAY JUST
WEST OF THE CWA ON MONDAY SO NO WIND HEADLINES FOR NOW. LATER
SHIFTS WILL REEVALUATE FOR ANY CHANGE TO THAT THINKING.
WINDS WILL BE DECREASING DURING THE DAY ON TUESDAY ONCE SYSTEM
MOVES EAST OF THE AREA TOWARD THE LOWER GREAT LAKES. TEMPERATURES
WILL BE COOL ON MONDAY DUE TO CLOUDS AND RAIN BUT THINGS WARM UP
QUICKLY TUESDAY INTO WEDNESDAY AS AN UPPER RIDGE MOVES OVER THE
CENTRAL PART OF THE NATION...ALTHOUGH 12Z ECMWF HOLDS ON TO THE
UPPER LOW OVER THE MID MISSISSIPPI VALLEY LONGER THAN THE NAM OR
GFS WHICH COULD KEEP CLOUDS OVER EASTERN PARTS OF THE AREA IF
THIS SOLUTION WORKS OUT.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 154 PM CDT SUN OCT 12 2014
EXTENDED MODELS SHOW SOME DIFFERENCE IN HANDLING OF THE UPPER
FEATURES DURING THE PERIOD...SO SOME UNCERTAINTY IN THIS PART OF
THE FORECAST. PRIMARY TREND AT THIS TIME LOOKS TO BE DRY WITH
SEASONAL TEMPERATURES.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 635 PM CDT SUN OCT 12 2014
A BAND OF -RA WILL CONT TO PROGRESS ACROSS THE TAF SITES THIS
EVENING AHEAD OF A COLD FRONT. GENERALLY VFR VISBY ARE EXPECTED
WITH THIS BAND THIS EVENING. OTHERWISE THE COLD FRONT WILL MAKE
SLOW STEADY PROGRESS ACROSS THE SITES THIS TONIGHT CLEARING ALL 3
BY 08Z. THE RA WILL TEND TO DECREASE LATE THIS EVENING WITH MORE
ISO SHRA OVERNIGHT. THE RA MAY INCREASE AGAIN MON MRNG AND CONT
INTO THE AFTN AT KOMA/KLNK AS THE STORM SYSTEM MOVES ACRS
KS/MO...ALTHOUGH THERE IS SOME UNCERTAINTY HOW FAR NORTH THE BAND
WILL MAKE IT. MVFR CIGS WILL CONT INTO MON AT KOMA AND MAY ALSO
MAKE IT INTO KLNK OVERNIGHT. GUSTY NORTHWEST WINDS ARE EXPECTED
DURING THE DAY ON MON.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...FOBERT
LONG TERM...FOBERT
AVIATION...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
825 PM EDT SUN OCT 12 2014
.SYNOPSIS...
HIGH PRESSURE OVER NEW YORK STATE WILL SLIDE EAST OFF THE NEW
ENGLAND COAST TONIGHT. A SOUTHERLY FLOW OF WARMER AND INCREASINGLY
MOIST AIR WILL OVERSPREAD THE REGION MONDAY AND LAST THROUGH
TUESDAY WITH A CHANCE FOR A FEW LIGHT RAIN SHOWERS. THE SOUTHERLY
WINDS WILL BRING MUCH MILDER WEATHER FOR THE REGION ESPECIALLY BY
TUESDAY AND WEDNESDAY WITH TEMPERATURES EXCEEDING 70 DEGREES IN
MANY LOCATIONS. A COLD FRONT WILL APPROACH THE REGION WEDNESDAY
WITH A CHANCE FOR MORE WIDESPREAD SHOWERS AND EVEN A FEW
THUNDERSTORMS BEFORE TEMPERATURES COOL DOWN LATER THIS WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
830 PM UPDATE...
BLIND SPOTS TO THE SOUTHWEST...AS WE ARE MISSING SOME RADAR DATA FROM
NEIGHBORING OFFICES. HOWEVER IT DOES APPEAR FROM THE MOSAIC
PICTURE THAT THE PRECIPITATION IS HAVING A HARD TIME MOVING NORTH
THROUGH THE COOL/DRY AIR MASS OVER CENTRAL PA. WILL NEED TO MAKE
ADJUSTMENTS TO PRECIP TIMING AND POPS TO BETTER REFLECT THE LATEST
TRENDS AND HRRR GUIDANCE.
3 PM UPDATE...
VISIBLE SATELLITE IMAGERY SHOWS A RARE SIGHT ACROSS CENTRAL NEW
YORK AND NORTHEAST PENNSYLVANIA...COMPLETELY CLEAR SKIES. EVEN
WITH BRIGHT SUNSHINE...MAXIMUM TEMPERATURES STILL WERE A LITTLE
BELOW NORMAL WITH 50S DOMINATE. THE VISIBLE IMAGERY SHOWS A LARGE
LOWER CLOUD SHIELD ACRS SRN OHIO...SW PA AND ACRS VA TO THE
DELMARVA. LATEST RAP AND NAM SHOWS THAT THE 850 MB RH FIELDS
CORRELATE WELL WITH THE NRN EDGE OF THIS CLD SHIELD TO THE S. WITH
A LARGE HIGH PRESSURE SYSTEM THAT IS CURRENTLY OVER NY PROJECTED
TO SLIDE OFF THE NORTHEAST COAST BY 12Z MON...A SOUTHERLY LOW
LEVEL FLOW WILL DEVELOP. THIS SRLY FLOW WILL ADVECT THIS CLD
SHIELD NORTHEASTWARD OVERNIGHT AND EVENTUALLY SPREAD ACRS ALL OF C
NY AND NE PA BTWN ABT MIDNIGHT AND 8 AM MON AS PER LATEST RAP 850
MB RH FIELDS. ADDTNLY...WARM AIR ADVECTION/ISENTROPIC LIFT WILL
BEGIN OVERNIGHT AND LAST THRU MONDAY. BUT THIS OCCURS AS THE UPPER
LEVEL HGTS RISE INDICATING THAT THE ISENTROPES ARE DESCENDING WITH
THE WAA. THUS SOME OF THE ISEN LIFT WILL BE CANCELLED LATE TONIGHT
THRU MONDAY. HENCE WE DON/T SEE A LOT OF PRECIP. AFTER
COLLABORATION WITH NEIGHBORING WFO`S DECIDED ON SLGHT TO CHC POPS
WITH THIS FIRST WAA WAVE THRU MON PM. HENCE INTRODUCE SLGHT CHC TO
CHC POPS BEGINNING LATE TONIGHT AND CONTINUING THRU MONDAY FOR
-SHRA. TEMPERATURES WILL BE ON THE REBOUND WITH MAXES REACHING
WELL INTO THE 60S...AND POSSIBLY 70F IN THE UPPER FINGER LAKES.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
FIRST WAA/ISEN LIFT SURGE PASSES BY MON PM WITH A FEW SHRA. THEN
OVERNIGHT MON TO TUE...ALL 4 SYNOPTIC SCALE MODELS INDICATE
INCREASING LL MOISTURE AND A SRLY FLOW AND WHAT LOOKS LIKE
DRIZZLE OR JUST A FEW LIGHT SHRA IN THE UPSLOPE REGIONS OF NE PA
AND SC NY/CATSKILLS. THUS HAVE SLGHT CHC-CHC POPS IN THESE AREAS
AND NO POPS FARTHER N TO THE LAKE ONTARIO PLAIN TO UPPER MOHAWK
VALLEY.
FOR TUESDAY NIGHT...SRLY FLOW INCREASES AREA WIDE WITH INCREASING MOISTURE
TRANSPORT INTO NY AND PA. THERE ARE UNCERTAINTIES AS TO THE TIMING
OF THE ARRIVAL OF THE MAIN FRNTL BAND OF SHRA WITH THE PROGRESSION
OF THE UPPER LEVEL LOW EASTWARD. ALL SYNOPTIC MODELS INDICATE THAT
THE UPPER LEVEL LOW REACHES THE WRN OHIO VALLEY 12Z WED. BUT THE
STRGEST PRESSURE GRADIENT AND ASSCTD LL FLOW AND MOISTURE
TRANSPORT VARIES IN PLACEMENT DEPENDING ON MODEL. THE CMC IS
FASTEST WITH PLENTY OF MOISTURE OVER NY AND PA BY 12Z WED. THE
EURO IS THE SLOWEST WITH HARDLY ANY PRECIP OR MOISTURE REACHING
NE PA OR C NY BY 12Z WED. THE GFS AND NAM ARE IN BTWN. SO I HAVE
BROADENED POPS ACRS CWA TUE NGT TO ACCOUNT FOR THE UNCERTAINTIES
AND LEAVE THEM IN THE SLGHT CHC TO CHC RANGE.
FOR WEDNESDAY...MODELS AGAIN VARY ON HOW QUICKLY THE UPPER LEVEL
LOW MOVES TO THE EAST BUT ALL INDICATE PRECIP OVER NY AND PA SO
HAVE LIKELY POPS...ESP BY WED AFTERNOON. GFS AND NAM INDICATE SOME
INSTABILITY AS WELL AS COLDER AIR MOVES IN ALOFT ABV THE WARM AND
FAIRLY MOIST AIR MASS IN PLACE. SO WE CONTINUE MENTION OF SOME
TSRA FOR WED IN GRIDS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
315 PM EDT UPDATE...
FOLLOWED CLOSELY TO WPC GUIDANCE AND MADE MINOR ADJUSTMENTS TO THE
PREVIOUS FORECAST. THE EXTENDED FORECAST PERIOD CONTINUES TO LOOK
UNSETTLED. THE PORTENT UPPR LVL LOW THAT IS STARTING TO DIG SOUTH
ALONG THE EASTERN SIDE OF THE ROCKIES WILL CONTINUE TO DIG SOUTH
AND AMPLIFY THROUGH MONDAY MORNING. THE LOW WILL SLOWLY MOVE EAST
AND BECOME CLOSED IN NATURE BY TUESDAY EVENING. THIS LOW WILL BE
THE CULPRIT FOR THE CHANCE FOR RAIN SHOWERS THROUGH FRIDAY.
ANOTHER SHORTWAVE TROUGH WILL SWING INTO THE REGION IN ITS WAKE
SATURDAY MORNING RESULTING IN THE CHANCE FOR ADDITIONAL SHOWERS
THROUGH THE WEEKEND. THUS KEEP AT LEAST CHANCE FOR SHOWERS THROUGH
THE WHOLE PERIOD.
TEMPS DURING THIS TIME FRAME WILL BE AT OR ABOVE THE SEASONAL
NORM.
&&
.AVIATION /01Z MONDAY THROUGH FRIDAY/...
00Z MON UPDATE... VFR CONDS ARE FORESEEN MOST OF THE PD...BUT SOME
MVFR CIG RESTRICTIONS COULD CREEP INTO PTNS OF THE AREA EARLY TMRW
MRNG...AND AGN PERHAPS LATE IN THE DAY.
STRENGTHENING SRLY FLOW WILL BRING A LARGE AREA OF MOISTURE/CLDNS
INTO CNY/NE PA...STARTING EARLY MON (DURG THE PRE-DAWN HRS). FOR
THE MOST PART...CIG BASES ARE LIKELY TO BE IN THE VFR RANGE
(GENERALLY 3500-4500 FT AGL). HOWEVER...AT THE LEADING EDGE OF
THIS CLOUD SHIELD EARLY MON (ROUGHLY 10-14Z)...AND ALSO LATE IN
THE DAY (MAINLY AFTER 22Z)...SOME MVFR CIG BASES ARE PSBL AT
KAVP/KELM/KITH/KBGM. KSYR AND KRME ARE EXPECTED TO STAY UNRESTRICTED.
SFC WINDS MAINLY AOB 5 KT MOST OF TNT...WILL INCREASE MON...WITH
GUSTS OF 22-25 KT LIKELY AREA-WIDE OUT OF THE S OR SE.
OUTLOOK...
MON NGT TO TUE...DEEP SRLY FLOW AHEAD OF CNTRL U.S.
TROF...RESULTING IN PERIODIC RESTRICTIONS DUE TO CIGS/SHRA/BR.
TUE NGT TO THURS...STEADY RAIN...RESULTING IN MVFR...AND POSSIBLY
IFR CONDITIONS.
FRIDAY...RESTRICTIONS POSSIBLE IN LIGHT RAIN SHOWERS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN/DJP
SHORT TERM...DJN
LONG TERM...KAH
AVIATION...KAH/MLJ
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
740 PM EDT SUN OCT 12 2014
.SYNOPSIS...
HIGH PRESSURE OVER NEW YORK STATE WILL SLIDE EAST OFF THE NEW
ENGLAND COAST TONIGHT. A SOUTHERLY FLOW OF WARMER AND INCREASINGLY
MOIST AIR WILL OVERSPREAD THE REGION MONDAY AND LAST THROUGH
TUESDAY WITH A CHANCE FOR A FEW LIGHT RAIN SHOWERS. THE SOUTHERLY
WINDS WILL BRING MUCH MILDER WEATHER FOR THE REGION ESPECIALLY BY
TUESDAY AND WEDNESDAY WITH TEMPERATURES EXCEEDING 70 DEGREES IN
MANY LOCATIONS. A COLD FRONT WILL APPROACH THE REGION WEDNESDAY
WITH A CHANCE FOR MORE WIDESPREAD SHOWERS AND EVEN A FEW
THUNDERSTORMS BEFORE TEMPERATURES COOL DOWN LATER THIS WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
VISIBLE SATELLITE IMAGERY SHOWS A RARE SIGHT ACROSS CENTRAL NEW
YORK AND NORTHEAST PENNSYLVANIA...COMPLETELY CLEAR SKIES. EVEN
WITH BRIGHT SUNSHINE...MAXIMUM TEMPERATURES STILL WERE A LITTLE
BELOW NORMAL WITH 50S DOMINATE. THE VISIBLE IMAGERY SHOWS A LARGE
LOWER CLOUD SHIELD ACRS SRN OHIO...SW PA AND ACRS VA TO THE
DELMARVA. LATEST RAP AND NAM SHOWS THAT THE 850 MB RH FIELDS
CORRELATE WELL WITH THE NRN EDGE OF THIS CLD SHIELD TO THE S. WITH
A LARGE HIGH PRESSURE SYSTEM THAT IS CURRENTLY OVER NY PROJECTED
TO SLIDE OFF THE NORTHEAST COAST BY 12Z MON...A SOUTHERLY LOW
LEVEL FLOW WILL DEVELOP. THIS SRLY FLOW WILL ADVECT THIS CLD
SHIELD NORTHEASTWARD OVERNIGHT AND EVENTUALLY SPREAD ACRS ALL OF C
NY AND NE PA BTWN ABT MIDNIGHT AND 8 AM MON AS PER LATEST RAP 850
MB RH FIELDS. ADDTNLY...WARM AIR ADVECTION/ISENTROPIC LIFT WILL
BEGIN OVERNIGHT AND LAST THRU MONDAY. BUT THIS OCCURS AS THE UPPER LEVEL
HGTS RISE INDICATING THAT THE ISENTROPES ARE DESCENDING WITH THE
WAA. THUS SOME OF THE ISEN LIFT WILL BE CANCELLED LATE TONIGHT
THRU MONDAY. HENCE WE DON/T SEE A LOT OF PRECIP. AFTER
COLLABORATION WITH NEIGHBORING WFO`S DECIDED ON SLGHT TO CHC POPS
WITH THIS FIRST WAA WAVE THRU MON PM. HENCE INTRODUCE SLGHT CHC TO
CHC POPS BEGINNING LATE TONIGHT AND CONTINUING THRU MONDAY FOR
-SHRA. TEMPERATURES WILL BE ON THE REBOUND WITH MAXES REACHING
WELL INTO THE 60S...AND POSSIBLY 70F IN THE UPPER FINGER LAKES.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
FIRST WAA/ISEN LIFT SURGE PASSES BY MON PM WITH A FEW SHRA. THEN
OVERNIGHT MON TO TUE...ALL 4 SYNOPTIC SCALE MODELS INDICATE
INCREASING LL MOISTURE AND A SRLY FLOW AND WHAT LOOKS LIKE
DRIZZLE OR JUST A FEW LIGHT SHRA IN THE UPSLOPE REGIONS OF NE PA
AND SC NY/CATSKILLS. THUS HAVE SLGHT CHC-CHC POPS IN THESE AREAS
AND NO POPS FARTHER N TO THE LAKE ONTARIO PLAIN TO UPPER MOHAWK
VALLEY.
FOR TUESDAY NIGHT...SRLY FLOW INCREASES AREA WIDE WITH INCREASING MOISTURE
TRANSPORT INTO NY AND PA. THERE ARE UNCERTAINTIES AS TO THE TIMING
OF THE ARRIVAL OF THE MAIN FRNTL BAND OF SHRA WITH THE PROGRESSION
OF THE UPPER LEVEL LOW EASTWARD. ALL SYNOPTIC MODELS INDICATE THAT
THE UPPER LEVEL LOW REACHES THE WRN OHIO VALLEY 12Z WED. BUT THE
STRGEST PRESSURE GRADIENT AND ASSCTD LL FLOW AND MOISTURE
TRANSPORT VARIES IN PLACEMENT DEPENDING ON MODEL. THE CMC IS
FASTEST WITH PLENTY OF MOISTURE OVER NY AND PA BY 12Z WED. THE
EURO IS THE SLOWEST WITH HARDLY ANY PRECIP OR MOISTURE REACHING
NE PA OR C NY BY 12Z WED. THE GFS AND NAM ARE IN BTWN. SO I HAVE
BROADENED POPS ACRS CWA TUE NGT TO ACCOUNT FOR THE UNCERTAINTIES
AND LEAVE THEM IN THE SLGHT CHC TO CHC RANGE.
FOR WEDNESDAY...MODELS AGAIN VARY ON HOW QUICKLY THE UPPER LEVEL
LOW MOVES TO THE EAST BUT ALL INDICATE PRECIP OVER NY AND PA SO
HAVE LIKELY POPS...ESP BY WED AFTERNOON. GFS AND NAM INDICATE SOME
INSTABILITY AS WELL AS COLDER AIR MOVES IN ALOFT ABV THE WARM AND
FAIRLY MOIST AIR MASS IN PLACE. SO WE CONTINUE MENTION OF SOME
TSRA FOR WED IN GRIDS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
315 PM EDT UPDATE...
FOLLOWED CLOSELY TO WPC GUIDANCE AND MADE MINOR ADJUSTMENTS TO THE
PREVIOUS FORECAST. THE EXTENDED FORECAST PERIOD CONTINUES TO LOOK
UNSETTLED. THE PORTENT UPPR LVL LOW THAT IS STARTING TO DIG SOUTH
ALONG THE EASTERN SIDE OF THE ROCKIES WILL CONTINUE TO DIG SOUTH
AND AMPLIFY THROUGH MONDAY MORNING. THE LOW WILL SLOWLY MOVE EAST
AND BECOME CLOSED IN NATURE BY TUESDAY EVENING. THIS LOW WILL BE
THE CULPRIT FOR THE CHANCE FOR RAIN SHOWERS THROUGH FRIDAY.
ANOTHER SHORTWAVE TROUGH WILL SWING INTO THE REGION IN ITS WAKE
SATURDAY MORNING RESULTING IN THE CHANCE FOR ADDITIONAL SHOWERS
THROUGH THE WEEKEND. THUS KEEP AT LEAST CHANCE FOR SHOWERS THROUGH
THE WHOLE PERIOD.
TEMPS DURING THIS TIME FRAME WILL BE AT OR ABOVE THE SEASONAL
NORM.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
00Z MON UPDATE... VFR CONDS ARE FORESEEN MOST OF THE PD...BUT SOME
MVFR CIG RESTRICTIONS COULD CREEP INTO PTNS OF THE AREA EARLY TMRW
MRNG...AND AGN PERHAPS LATE IN THE DAY.
STRENGTHENING SRLY FLOW WILL BRING A LARGE AREA OF MOISTURE/CLDNS
INTO CNY/NE PA...STARTING EARLY MON (DURG THE PRE-DAWN HRS). FOR
THE MOST PART...CIG BASES ARE LIKELY TO BE IN THE VFR RANGE
(GENERALLY 3500-4500 FT AGL). HOWEVER...AT THE LEADING EDGE OF
THIS CLOUD SHIELD EARLY MON (ROUGHLY 10-14Z)...AND ALSO LATE IN
THE DAY (MAINLY AFTER 22Z)...SOME MVFR CIG BASES ARE PSBL AT
KAVP/KELM/KITH/KBGM. KSYR AND KRME ARE EXPECTED TO STAY UNRESTRICTED.
SFC WINDS MAINLY AOB 5 KT MOST OF TNT...WILL INCREASE MON...WITH
GUSTS OF 22-25 KT LIKELY AREA-WIDE OUT OF THE S OR SE.
OUTLOOK...
MON NGT TO TUE...DEEP SRLY FLOW AHEAD OF CNTRL U.S.
TROF...RESULTING IN PERIODIC RESTRICTIONS DUE TO CIGS/SHRA/BR.
TUE NGT TO THURS...STEADY RAIN...RESULTING IN MVFR...AND POSSIBLY
IFR CONDITIONS.
FRIDAY...RESTRICTIONS POSSIBLE IN LIGHT RAIN SHOWERS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...KAH
AVIATION...KAH/MLJ
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
656 PM EDT SAT OCT 11 2014
.SYNOPSIS...
A COLD FRONT WILL DROP SOUTH ACROSS THE AREA DURING THE LATE
AFTERNOON AND EVENING. THE FRONT WILL STALL TO THE SOUTH ON SUNDAY
AND DISSIPATE OVER THE AREA. A STRONG COLD FRONT WILL APPROACH
FROM THE WEST LATE TUESDAY AND CROSS EASTERN NORTH CAROLINA TUESDAY
NIGHT INTO WEDNESDAY. HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT
LATE NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 630 PM SATURDAY...COLD FRONT HAS NOW MOVED INTO NORTHERN
SECTIONS OF THE CWA AND IS NOW AS FAR SOUTH AS OREGON INLET TO
NEAR KPGV. SOME SCATTERED STRONG THUNDERSTORMS ARE OCCURRING JUST
ALONG OR JUST BEHIND THE FRONT. AXIS OF INSTABILITY SHOULD MOVE
SOUTH WITH A THREAT OF A TSTMS LINGERING OVER SOUTHERN SECTIONS
THROUGH ABOUT 01Z-03Z WHEN THE 3KM HRRR SHOWS THE FRONT MOVING OFF
THE COAST. PRIMARY THREAT WITH ANY STORMS WOULD BE HAIL AND
FREQUENT LIGHTNING WITH SOME WINDS GUSTS POSSIBLE AS WELL. THE
PRECIPITATION SHOULD TAPER OFF TO LIGHT RAIN/DRIZZLE AFTER
MIDNIGHT AS THE COOL AND STABLE NNE FLOW KICKS IN. TEMPERATURES
WILL DROP DRASTICALLY FROM RECORD HIGHS SATURDAY AFTERNOON INTO
THE MID AND UPPER 50S INLAND AND LOW/MID 60S COAST BY SUNRISE
SUNDAY.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
QUITE A TURNAROUND FROM SATURDAYS VERY WARM AND SUNNY CONDITIONS.
HIGH PRESSURE TO THE NORTH RIDGES SSW THRU THE MID ATLC REGION AND
CAROLINAS SUNDAY. THICK LOW LEVEL MOISTURE WILL BE DIFFICULT TO
SCOUR OUT IN THE PERSISTENT N/NE FLOW ON SUNDAY SO EXPECT MAINLY
CLOUDY SKIES WITH A CONTINUING CHANCE OF LIGHT RAIN THROUGH MUCH
OF THE DAY. CLOUDS AND COOL LOW LEVEL FLOW WILL HOLD TEMPS IN THE
60S FOR MOST AREAS THRU SUNDAY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
AS OF 315 PM SAT...THE FRONTAL BOUNDARY WILL RESIDE SOUTH OF THE
REGION SUN NIGHT WITH HIGH PRES CENTERED OVER THE NORTHERN MID
ATLANTIC RIDGING INTO THE REGION BRINGING NE FLOW AND PLENTY OF
LOW LEVEL MOISTURE. SKIES WILL LIKELY REMAIN CLOUDY/MOSTLY CLOUDY
WITH PATCHY DRIZZLE OR LIGHT RAIN POSSIBLE. THE HIGH SLIDES OFFSHORE
EARLY MON WITH SE FLOW RETURNING AND CONTINUING INTO MON NIGHT.
ONSHORE FLOW CONTINUES TO BRING ABUNDANT MOISTURE BELOW H85 AND
CANNOT RULE OUT AN ISOLATED SHOWER THIS PERIOD AS WELL THUS WILL
MAINTAIN 20 POPS. TEMPS WARM BACK INTO THE LOWER 80S INLAND AND
MID/UPPER 70S ALONG THE COAST FOR MONDAY.
SURFACE FLOW SHIFTS SOUTHEASTERLY TUES AS A ROBUST UPPER TROUGH DIGS
INTO THE CENTRAL CONUS AND AN AREA OF LOW PRESSURE DEVELOPS NEAR THE
OHIO RIVER VALLEY. THE LOW WILL SLOWLY PUSH NORTHEAST INTO THE
SOUTHERN GREAT LAKES AND DRAG A COLD FRONT THROUGH EASTERN NC
SOMETIME LATE TUES NIGHT INTO WED. 12Z GUIDANCE HAS SLOWED QUITE A
BIT WITH THE SURFACE FRONT AND THE GFS HAS TRENDED SIMILAR TO THE
PAST SEVERAL RUNS OF THE ECMWF IN DEVELOPING A LARGE CUT-OFF UPPER
LOW OVER THE MIDWEST. FORECAST NOW SLOWS DOWN THE PRECIP SLIGHTLY
TUES NIGHT THROUGH WED EVENING. THE UPPER LOW LIFTS NE ACROSS THE
MIDWEST THURS AND INTO SOUTHEASTERN CANADA FRIDAY. STRONG TO
POTENTIALLY SEVERE THUNDERSTORMS WILL BE POSSIBLE AHEAD OF AND
ALONG THE FRONT TUES AFTERNOON INTO TUES NIGHT AS FORECAST SOUNDINGS
INDICATE MODEST INSTABILITY AND STRONG SHEAR AND HELICITY. A STRONG
SURFACE RIDGE WILL SHIFT EAST OVER THE REGION LATE WED NIGHT INTO
THURS...THEN SLIDE OFFSHORE FRI INTO SAT. INCREASING SOUTHERLY FLOW
WILL AGAIN PUSH TEMPS SEVERAL DEGREES ABOVE CLIMATOLOGY TUES WITH
LOW LEVEL THICKNESSES BUILDING 1390-1400 METERS...THEN NEAR TO A FEW
DEGREES BELOW NORMAL MID TO LATE WEEK AS THICKNESSES LOWER WITH THE
FRONTAL PASSAGE. MAX TEMPS EXPECTED TO RANGE IN THE LOWER TO MID 80S
TUES WITH LOW TO MID 70S WED THROUGH SAT.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
SHORT TERM /THROUGH 18Z SUNDAY/...
AS OF 630 PM SATURDAY...GOOD CONFIDENCE THAT AVIATION CONDITIONS
WILL GRADUALLY DETERIORATE OVERNIGHT AS COLD FRONT MOVES SOUTH OF
THE AREA AND DAMP N/NE FLOW KICKS IN. ONCE FRONT MOVES OFFSHORE IN
THE 01Z-03Z TIME FRAME...EXPECT IFR CEILINGS TO DEVELOP AND
CONTINUE OVERNIGHT AND THROUGH MOST OF THE MORNING ON SATURDAY.
NORTHEAST WINDS WILL EVENTUALLY INCREASE SUNDAY THROUGH MID-
MORNING HOURS WHICH MAY HELP TO SCATTER OUT THE LOW LEVEL
MOISTURE.
LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/
AS OF 315 PM SAT...A FRONTAL BOUNDARY WILL BE POSITIONED SOUTH OF
THE AREA WITH HIGH PRES BUILDING IN FROM THE NORTH SUN NIGHT
WITH NE FLOW AND ABUNDANT LOW LEVEL MOISTURE BRINGING A
STRATOCUMULUS DECK WITH PATCHY DRIZZLE OR LIGHT RAIN
POSSIBLE...HOWEVER MOS GUIDANCE CURRENTLY INDICATING CIGS MVFR OR
ABOVE. SURFACE FLOW SHIFTS SOUTHEASTERLY MON ALLOWING TEMPS AND
DEWPOINTS TO INCREASE...WITH AN ISOLATED CHANCE FOR SHOWERS. A
STRONG COLD FRONT WILL APPROACH THE REGION TUES AND COULD SEE
STRONG THUNDERSTORMS ACROSS THE REGION LATER IN THE DAY TUES.
BRIEF OVERNIGHT FOG/STRATUS MAY BE AN ISSUE EARLY MON AND TUES
MORNING THOUGH LIGHT SURFACE MIXING MAY PRECLUDE FOG DEVELOPMENT.
&&
.MARINE...
SHORT TERM /THROUGH SUNDAY/...
AS OF 650 PM SATURDAY...FRONT HAS DROPPED TO NEAR OREGON INLET AND
THROUGH THE ALBEMARLE SOUND. WINDS ALREADY GUSTING TO 26 KNOTS AT
DUCK PIER AND WILL BEGIN THE SMALL CRAFT ADVISORY EARLIER FOR THE
NORTHERN TIER. WINDS SHOULD INCREASE FROM NORTH TO SOUTH AS THE
FRONT DIVES SOUTH AND MOVES OFFSHORE BETWEEN 01Z-03Z. THE GUSTY
NE WINDS WILL LEAD TO SEAS BUILDING TO 4 TO 6 FT N OF OCRACOKE
OVERNIGHT. NNE WINDS WILL CONTINUE 15-20 KTS THRU MUCH OF SUNDAY
BEFORE BEGINNING TO WEAKEN LATER SUNDAY AFTN. SEAS REMAIN AT LEAST
4-6 FT THRU SUNDAY.
LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/
AS OF 315 PM SAT...HIGH PRESSURE BUILDING IN FROM THE NORTH WILL
CONTINUE TO BRING N/NE WINDS AROUND 10-20 KT SUN...WHICH WEAKENS TO
BELOW 15 KT SUN NIGHT. SOUTHEASTERLY FLOW DEVELOPS BY MON AS SFC
HIGH PRES SLIDES OFFSHORE. WINDS SHIFT TO SOUTH TO SOUTHEASTERLY AND
INCREASES TO 15-25 KT TUES/TUES NIGHT...AND POSSIBLY AS STRONG AS 30
KT TUE NIGHT AHEAD OF A STRONG COLD FRONT. MODELS HAVE TRENDED
SLOWER WITH THE FRONTAL PASSAGE ACROSS THE WATERS WED EVENING/NIGHT
ABOUT 12 HRS SLOWER THAN THE PREVIOUS SEVERAL FORECASTS. WEST TO
NORTHWEST WINDS AROUND 10-20 KT EXPECTED AFTER FRONTAL PASSAGE WED
NIGHT INTO THURS.
LOCAL NWPS/SWAN AND WAVEWATCH CONTINUE TO INDICATE SEAS SUBSIDING
BELOW 6 FT ACROSS THE CENTRAL WATERS SUN NIGHT. SEAS SUBSIDE
SLIGHTLY MON...BUT ARE PROGGED TO INCREASE QUICKLY TUES AFTERNOON AS
SE/SLY FLOW INCREASES PEAKING AROUND 6-8 FT AND POSSIBLY
HIGHER LATE TUES NIGHT INTO WED...THOUGH UNCERTAINTY REMAINS WITH
REGARD TO PEAK WINDS AND SEAS DUE TO MODEL INCONSISTENCIES AT THIS
TIME. SEAS SUBSIDE TO 2-4 FT THURS WITH SOME 5 FT SEAS POSSIBLE FOR
THE OUTER FRINGES OF THE COASTAL WATERS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 AM SUNDAY TO 6 AM EDT MONDAY FOR
AMZ152-154.
SMALL CRAFT ADVISORY FROM 11 PM THIS EVENING TO 8 PM EDT
SUNDAY FOR AMZ150.
&&
$$
SYNOPSIS...BTC
NEAR TERM...CTC/BTC
SHORT TERM...BTC
LONG TERM...SK/DAG
AVIATION...CTC/DAG/LEP
MARINE...CTC/BTC/SK/DAG
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
135 AM EDT SAT OCT 11 2014
.SYNOPSIS...
WEAK HIGH PRESSURE WILL PREVAIL ACROSS THE AREA OVERNIGHT INTO
SATURDAY. A COLD FRONT APPROACHING FROM THE NORTH WILL THEN DROP
INTO THE AREA SATURDAY NIGHT...BEFORE PUSHING TO THE SOUTH ON
SUNDAY AS A WEDGE OF HIGH PRESSURE BUILDS FROM THE NORTH. THE
FRONT WILL RETREAT BACK TO THE NORTH ON MONDAY...WITH A STRONG
COLD FRONT THEN EXPECTED TO SWEEP ACROSS THE AREA TUESDAY NIGHT
WITH A RISK FOR STRONG THUNDERSTORMS. HIGH PRESSURE WILL THEN
BUILD OVER THE REGION INTO LATE NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1:30 AM SATURDAY...NO CHANGES TO THE FORECAST WITH THE
LATEST UPDATE. PREVIOUS DISCUSSIONS FOLLOW:
THE 00Z CHS SOUNDING CAME IN 2-3 DEGREES F WARMER THAN 18Z MODELS
PREDICTED THROUGH THE LOWEST 75 MB OF THE ATMOSPHERE. THIS...PLUS
02Z (10 PM) TEMPERATURES RUNNING A LITTLE ABOVE MY EARLIER
FORECAST HAS LED ME TO RAISE FORECAST LOWS BY ANOTHER DEGREE IN
MOST SPOTS. CONVECTION ACROSS DARLINGTON AND MARLBORO COUNTIES HAS
DISSIPATED. RECENT HRRR MODELS DO NOT INDICATE MUCH POTENTIAL FOR
ADDITIONAL CONVECTION OVERNIGHT. ACTIVITY IN AND NEAR RALEIGH
SHOULD STAY TO OUR NORTH. PREVIOUS DISCUSSION FROM 730 PM
FOLLOWS...
ALTHOUGH THERE IS NOT A DEFINABLE FRONT ACROSS THE EASTERN
CAROLINAS THERE IS A DISCONTINUITY IN ATMOSPHERIC MOISTURE
CONTENT. RECENT MESOANALYSIS SHOWS PRECIPITABLE WATER VALUES NEAR
1.4 INCHES WEST OF INTERSTATE 95 WITH ONLY 1.0 INCH ON THE COAST.
VERTICALLY...THIS INCREASED MOISTURE IS MOST APPARENT AT THE 900
AND 850 MB LEVEL WHICH IS VERY NEAR THE TOP OF TODAY`S DIURNALLY
MIXED LAYER. SURFACE-BASED INSTABILITY NEAR 1000 J/G CONTINUES
ACROSS THE CENTRAL SOUTH CAROLINA AS FAR EAST AS I-95 WHERE A
COUPLE CLUSTERS OF SHOWERS AND T-STORMS HAVE DEVELOPED. THIS
ACTIVITY IS ROLLING EAST-NORTHEASTWARD ACROSS HARTSVILLE AND
DARLINGTON. OUR CONVECTION DOES NOT HAVE A BRIGHT FUTURE AHEAD OF
IT: A STABILIZING BOUNDARY LAYER AND LESS MOISTURE DOWNSTREAM
SHOULD BOTH ACT TO END THIS CONVECTION OVER THE NEXT FEW HOURS.
SYNOPTICALLY...SUBTROPICAL HIGH PRESSURE OVER THE NORTHERN GULF IS
PRODUCING A WEST-SOUTHWEST FLOW IN THE MID AND UPPER LEVELS OVER
THE CAROLINAS. AT LEAST TWO WEAK POSITIVELY-TILED SHORTWAVES WILL
MOVE WITHIN A RIBBON OF DEEP MOISTURE ACROSS TENNESSEE...NORTHERN
NORTH CAROLINA AND VIRGINIA OVERNIGHT. AT THE SURFACE LOW PRESSURE
WILL MOVE NORTHEAST ALONG A NEARLY STATIONARY FRONT ACROSS
TENNESSEE INTO VIRGINIA. THIS SHOULD KEEP MOST OF THE SYNOPTIC
ACTION WELL OFF TO OUR NORTH WITH ONLY CIRRUS AND OCCASIONAL MID
CLOUDS DOWN THIS WAY.
A MODERATE LOW LEVEL JET SHOULD DEVELOP SHORTLY WITH WIND SPEEDS
AT 1000 FEET AGL INCREASING TO 20 KT. (THE NAM INCREASES THESE
WIND SPEEDS TO 30 KNOTS OVERNIGHT...QUITE A BIT STRONGER THAN THE
GFS) THIS SHOULD HELP DISTURB THE BOUNDARY LAYER JUST ENOUGH TO
PREVENT A DEEP SUBSIDENCE INVERSION FROM DEVELOPING...AND FORECAST
LOWS ARE NEAR THE TOP END OF THE MOS GUIDANCE ENVELOPE: MID 60S
MOST AREAS WITH UPPER 60S AT THE BEACHES. INTERESTINGLY SINCE THIS
LOW LEVEL JET WILL BE WEAKER THE FARTHER SOUTH YOU ARE...THE
STRONGEST RADIATIONAL INVERSION SHOULD DEVELOP SOUTH OF FLORENCE
AND MYRTLE BEACH AND I HAVE LOWER 60S FORECAST TO OCCUR IN THE
GEORGETOWN/ CONWAY VICINITY AS A RESULT.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
AS OF 400 PM FRIDAY...SATURDAY AND SATURDAY NIGHT...WEAK HIGH
PRESSURE WILL LINGER OVER THE AREA ON SATURDAY AS A BACKDOOR COLD
FRONT DROPS TOWARD THE AREA FROM THE NORTH. THE FRONT WILL DROP
INTO SOUTHEAST NORTH CAROLINA SATURDAY EVENING...THEN SLOWLY
PROGRESS SOUTHWARD THROUGH THE NIGHT AS SURFACE HIGH PRESSURE
SHIFTS EAST OUT OF THE GREAT LAKES REGION. ANY SHOWERS AND
THUNDERSTORMS ON SATURDAY SHOULD BE ISOLATED...AND MAINLY LIMITED
TO SOUTHEAST NORTH CAROLINA IN THE AFTERNOON IN CLOSER PROXIMITY
TO THE NEARING FRONT. THE POTENTIAL FOR SHOWERS WILL INCREASE INTO
THE CHANCE CATEGORY SATURDAY EVENING ACROSS MOST OF THE AREA AS
THE FRONT BEGINS TO MOVE THROUGH. AS FOR
TEMPERATURES...COMPRESSIONAL HEATING AHEAD OF THE BACKDOOR FRONT
SHOULD ALLOW FOR HIGHS IN THE MID TO UPPER 80S ACROSS THE AREA
INLAND FROM THE COAST. LOWS SATURDAY NIGHT SHOULD BE RATHER MILD
IN THE LOWER TO MID 60S GIVEN INCREASING CLOUD COVER.
SUNDAY AND SUNDAY NIGHT...THE FRONT WILL PROGRESS SOUTH OF THE
AREA ON SUNDAY AS AN INLAND WEDGE BUILDS DOWN THE LEE OF THE
APPALACHIANS WITH THE PARENT HIGH CENTERED OVER NEW ENGLAND.
ABUNDANT LOW LEVEL MOISTURE WILL BECOME TRAPPED BENEATH THE STRONG
INVERSION... RESULTING IN CONSIDERABLE CLOUDINESS. FORCING FOR
ASCENT IS RATHER WEAK...BUT THE ABUNDANT LOW LEVEL MOISTURE
COMBINED WITH WEAK ISENTROPIC LIFT SHOULD SUPPORT A SLIGHT CHANCE
OF RAIN AND/OR PATCHY DRIZZLE ACROSS THE AREA...WITH NOT MUCH IN
THE WAY OF MEASURABLE RAINFALL EXPECTED. TEMPERATURES WILL BE
SIGNIFICANTLY COOLER WITH THE WEDGE IN PLACE AND HIGHS ARE ONLY
FORECAST TO BE IN THE LOWER 70S ACROSS SOUTHEAST NC AND LOWER TO
MID 70S ACROSS MOST OF NORTHEAST SC.
MONDAY...THE PARENT HIGH WILL SHIFT OFF THE NEW ENGLAND
COAST...THUS ALLOWING A WARM FRONT TO LIFT NORTH ACROSS THE AREA
AS AN UPPER RIDGE BUILDS OVER THE WESTERN ATLANTIC. HOWEVER...FEEL
AS IS TYPICALLY THE CASE THE MODELS ARE ERODING THE WEDGE A BIT
TOO QUICKLY. WILL TREND WARMER WITH HIGHS IN THE UPPER 70S TO NEAR
80 AND MAINTAIN A SLIGHT CHANCE OF SHOWERS IN THE FORECAST...WITH
PERHAPS A FEW AFTERNOON THUNDERSTORMS IF THE WEDGE CAN GET
DISPLACED.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 400 PM FRIDAY...A DEEP UPPER LEVEL TROUGH/CLOSED LOW TO THE
WEST WILL ALLOW A POTENT COLD FRONT TO SWING THROUGH THE AREA BY
MID-WEEK. MEDIUM RANGE GUIDANCE SHOWS CONSIDERABLE TIMING
DIFFERENCES...WITH FRONTAL PASSAGE OCCURRING ANYWHERE FROM LATE
TUESDAY TO WEDNESDAY MORNING. GIVEN HOW THE UPPER LOW WRAPS UP IT
SHOULD SLOW THE SYSTEM DOWN AND THE SLOWER SOLUTIONS APPEAR MORE
LIKELY...BUT WILL TAKE SOMEWHAT OF A COMPROMISE AND INDICATE THE
FRONT MOVING THROUGH TUESDAY NIGHT. WHAT MODELS DO AGREE WITH IS
THE POTENTIAL FOR STRONG OR SEVERE THUNDERSTORMS...GIVEN A
POWERFUL LOW LEVEL JET AHEAD OF THE FRONT AND OVERALL STRONG
DYNAMICS. THE BIGGEST FACTOR WILL BE THE AMOUNT OF AVAILABLE
INSTABILITY...WHICH WOULD CERTAINLY BE BETTER IF THE FRONT MOVED
THROUGH CLOSER TO PEAK HEATING. STILL...A HIGH SHEAR LOW CAPE
SCENARIO COULD SUPPORT A THREAT FOR DAMAGING WINDS ACROSS THE AREA
WITH THE PASSAGE OF THE FRONT AND WILL KEEP MENTION IN THE
HAZARDOUS WEATHER OUTLOOK.
TRUE FALL AIR WILL ENVELOP THE REGION WEDNESDAY THROUGH FRIDAY AS
HIGH PRESSURE BUILDS INTO THE REGION BEHIND THE FRONT...WITH
COOLER AND MUCH DRIER CONDITIONS EXPECTED.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 06Z...VFR EXPECTED AT ALL TERMINALS OVERNIGHT AS S-SW WINDS
AROUND 5 KT WILL KEEP THE BOUNDARY LAYER WELL MIXED. DO NOT
ANTICIPATE ANY FOG ATTM...EVEN FOR KFLO/KLBT...GIVEN THE STRONGER
LOW LEVEL WINDS AND SOME LINGERING DEBRIS CLOUDS. SAT WILL BE VFR
WITH SOUTHWEST WINDS AOB 10 KT AHEAD OF A COLD FRONT. CLOUDS WILL
INCREASE AS THE FRONT SAGS SOUTHWARD...AND HAVE ADDED VCSH FOR
KILM/KLBT BEGINNING AT 21Z SAT AND KCRE/KMYR/KFLO AT 00Z SUN IN
ASSOCIATION WITH THE BOUNDARY. BY THE END OF THE PERIOD...EXPECT
THE FRONT TO BE BISECTING THE FORECAST AREA...WITH NORTHERLY WINDS
AT KLBT/KILM AND LIGHT/VRBL WINDS AT THE SOUTHERN TERMINALS. THE
COOL AND SHALLOW N-NE FLOW WILL LEAD TO POST-FRONTAL MVFR/IFR
STRATUS AT THE NORTHERN TERMINALS BY 06Z SUN. WILL ONLY DROP CIGS
TO 1KFT AT KLBT/KILM ATTM BASED ON THE FCST SOUNDINGS AND GIVEN
THE UNCERTAINTY IN TIMING.
EXTENDED OUTLOOK...POST-FRONTAL MVFR/IFR CIGS EXPECTED SUN THROUGH
EARLY MON. VFR CONDITIONS SHOULD DEVELOP MON AFTN/NIGHT.
SHOWERS/TSTMS AND GUSTY WINDS EXPECTED TUE AFTN/NIGHT WITH A
STRONG COLD FRONT PASSAGE. VFR ON WEDNESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1:30 AM SATURDAY...NO CHANGES TO THE FORECAST WITH THE
LATEST UPDATE. PREVIOUS DISCUSSION FOLLOWS:
WINDS ARE RUNNING FAIRLY CLOSE TO PREDICTION ACROSS THE WATERS
NORTH OF MYRTLE BEACH...HOWEVER FROM MYRTLE BEACH SOUTHWARD
OBSERVATIONS HAVE BEEN RUNNING A FEW KNOTS BELOW FORECAST. ONLY
MINOR TWEAKS ARE NEEDED HOWEVER. LATEST OBSERVED SEAS REMAIN 1-2
FEET. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS...
A NEARLY STATIONARY FRONT EXTENDS ACROSS CENTRAL VIRGINIA WITH A
WEAKENING RIDGE OF HIGH PRESSURE ANALYZED JUST OFFSHORE. THIS IS
PRODUCING A ZONE OF RELATIVELY WEAK WINDS ACROSS THE OFFSHORE
WATERS BEYOND 50 MILES FROM SHORE AND ALSO ALONG THE GEORGIA
COAST...BUT THE FARTHER NORTH ONE TRAVELS WIND SPEEDS INCREASE.
THIS PATTERN SHOULD CONTINUE THROUGH THE NIGHT. LOCALLY...WIND
SPEEDS SHOULD INCREASE A FEW MORE KNOTS THIS EVENING AS A MODERATE
LOW LEVEL JET ORGANIZES OVERHEAD AND INCREASES WINDS AT 1000 FEET
ABOVE THE OCEAN SURFACE TO 20 KNOTS. DOWN AT THE OCEAN SURFACE
EXPECT WINDS TO INCREASE TO 10-15 KNOTS...HIGHEST NEAR AND NORTH
OF CAPE FEAR. SEAS CURRENTLY 1-2 FEET SHOULD EDGE CLOSER TO 2 FEET
WITH A BIT OF A WIND CHOP EXPECTED.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 400 PM FRIDAY...COLD FRONT WILL SINK SLOWLY ACROSS THE
WATERS DURING THE WEEKEND...PRODUCING TWO DISTINCTLY DIFFERENT
REGIMES. SATURDAY...THE FRONT WILL REMAIN NORTH OF THE AREA AND
THUS SW WINDS WILL OCCUR ACROSS THE WATERS...AT SPEEDS OF 10-15
KT. THE FRONT WILL BEGIN TO AFFECT THE WATERS VERY LATE SAT
NIGHT...DROPPING ACROSS AMZ250 FIRST...AND THEN PROCEEDING SOUTH
ACROSS AMZ256 LAST...BY SUNDAY MORNING. THIS FRONT WILL BE
ACCOMPANIED BY A SUDDEN WIND SHIFT TO THE NORTH...BECOMING
NORTHEAST...AND THEN EVENTUALLY EAST LATE SUNDAY...AS SPEEDS SURGE
UPWARDS OF 15-20 KT. WAVE HEIGHTS WILL BE 2-4 FT THROUGH THE
PERIOD...BUT A SOUTHERLY WIND WAVE AND WEAK SE SWELL WILL DOMINATE
THE SPECTRUM SATURDAY...WHILE A GROWING NE WIND WAVE WILL DEVELOP
THROUGH SUNDAY. THIS PRODUCES A CONFUSED SPECTRUM...ESPECIALLY SAT
NIGHT AND EARLY SUNDAY...WHEN MARINE CONDITIONS COULD BECOME
HAZARDOUS EVEN WHILE REMAINING BELOW ANY CAUTIONARY THRESHOLDS.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 400 PM FRIDAY...WINDS VEER MORE SOUTHERLY ON MONDAY IN A
PRE-FRONTAL AIR MASS...AND THEN STEADILY INCREASE IN SPEED DURING
TUESDAY AS A STRONG COLD FRONT APPROACHES FROM THE NW. WINDS
SPEEDS OF 15-20 KT WILL BE COMMON MONDAY NIGHT...TUESDAY AND
TUESDAY NIGHT WITH GUSTS UPWARD OF 25 KT AT TIMES. THESE WINDS
WILL DRIVE WAVE HEIGHTS UP TO 4-6 FT. A SMALL CRAFT ADVISORY WILL
LIKELY BE NEEDED MOST OF TUESDAY AND TUESDAY NIGHT. THERE IS STILL
SOME UNCERTAINTY INTO EXACTLY WHEN THE FRONT WILL CROSS THE
WATERS...BUT IT APPEARS TO BE TUESDAY NIGHT OR EARLY WEDNESDAY.
OFFSHORE WINDS WILL DEVELOP BEHIND THE FRONT LATER WEDNESDAY WITH
WINDS/SEAS IMPROVING.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...99
NEAR TERM...REK/TRA
SHORT TERM...99
LONG TERM...99
AVIATION...REK/BJR
MARINE...99/REK/TRA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
831 PM EDT SUN OCT 12 2014
.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST AND OFF THE EASTERN SEABOARD BY MONDAY
MORNING. LOW PRESSURE WILL MOVE NORTHEAST INTO THE CENTRAL GREAT
LAKES BY WEDNESDAY. A TROUGH OF LOW PRESSURE WILL MOVE EAST ACROSS
THE AREA ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
UPDATE...ADJUSTED POPS UP A BIT BASED ON HRRR AND NAM/GFS ADVANCE
OF RH AND UVV INTO THE AREA OVERNIGHT. PRECIP ALREADY
DEVELOPING/MOVING INTO WRN/SRN INDIANA AND KY.
ORIGINAL...MODELS HAVE BEEN A BIT FAST WITH THE PRECIPITATION AS
IT MOVES NORTHEAST TOWARD THE AREA. MOISTURE WILL STREAM NORTHEAST
TOWARD THE REGION OVERNIGHT BUT WILL HAVE A DIFFICULT TIME
ENCOUNTERING THE DRY AIR OVER THE REGION AT THIS TIME. SATELLITE
DATA SHOWS CLOUDS MOVING NORTHEAST AT THIS TIME INTO SOUTHWEST
OHIO STRUGGLING TO MAKE ANY HEADWAY. TIMING AS OF NOW WILL BE TO
MOVE AT LEAST A CHANCE FOR SHOWERS INTO THE SOUTHWEST CORNER OF
THE FORECAST AREA BY THIS EVENING AND TO CLEVELAND AND MANSFIELD
BY 11Z AND TO ERIE AND YOUNGSTOWN BY 14Z. INCREASING CLOUDINESS
WILL TAKE PLACE OVERNIGHT AS WELL.
TEMPERATURES IN THE SREF AND LOCAL MODEL HAVE BEEN DOING WELL SO FAR
AND WILL BE LEANING IN THAT DIRECTION FOR OVERNIGHT LOWS. WARM AIR
ADVECTION WILL TAKE PLACE OVERNIGHT AND LOWS WILL NOT BE ANY WHERE
NEAR THE LOWS THIS MORNING.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
DEEP DIGGING UPPER LEVEL LOW PRESSURE WILL MOVE EAST ACROSS THE AREA
OVER THE NEXT FEW DAYS. THIS FEATURE WILL REFLECT A LOW PRESSURE
SYSTEM AT THE SURFACE AND TRACK IT NORTHEAST THROUGH THE CENTRAL
GREAT LAKES. THIS IS INDICATIVE OF A TYPICAL FALL PATTERN AS LOWS
TEND TO TRACK IN A SIMILAR FASHION. MANY DIFFERENCES IN THE MODELS
IN TIMING OF THE PRECIPITATION. THE BOTTOM LINE IS THAT IT IS GOING
TO RAIN AT SOME POINT BETWEEN MONDAY AND WEDNESDAY NIGHT. WE
ACTUALLY SEE A COUPLE SURGES OF DRIER AIR ALTERNATING WITH MOISTURE
SURGES SO THERE COULD BE PERIODS OF NO PRECIPITATION. WILL TRY AND
HIGHLIGHT THE BETTER CHANCES FOR THE PRECIPITATION THREATS THROUGH
THIS PERIOD. AS THE UPPER LEVEL LOW MOVES IN OVER THE REGION ALONG
WITH THE PRE FRONTAL TROUGH AND COLD FRONT...THUNDER IS A
POSSIBILITY AND WILL KEEP AT LEAST A CHANCE OR ISOLATED THREAT FOR
THUNDERSTORMS.
WARM AIR ADVECTION WILL DEVELOP WELL AHEAD OF THE LOW PRESSURE
SYSTEM AND IN THE WAKE OF THE HIGH. THIS ALONE WILL HELP TO FORCE
SOME WARMER AIR INTO THE REGION. IF WE DO GET SOME BREAKS OF SUN
TOMORROW AND TUESDAY...TEMPERATURES WILL INDEED BE WELL INTO THE 70S
EACH DAY. WILL STAY IN THE MIDDLE OF THE ROAD FOR GUIDANCE MAX
TEMPERATURES. COLD AIR ADVECTION TAKES PLACE WEDNESDAY WITH THE
PASSAGE OF THE COLD FRONT.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
NOT MUCH CONFIDENCE IN THE TIMING OF RAINFALL ACROSS THE AREA
THROUGH THE LONG TERM AS AN UPPER LEVEL LOW PRESSURE WOBBLES OVER
THE REGION. THE UPPER LEVEL LOW MOVEMENT WILL LIKELY BE CLOSER IN
TIMING TO THE ECMWF. TEMPERATURES THURSDAY INTO FRIDAY LOOK LIKE
THEY WILL BE NEAR SEASONAL LEVELS BUT IT WILL ALL HINGE ON THE
AMOUNT OF CLOUD COVER THAT DEVELOPS UNDER THE COLD CORE OF AIR
ALOFT. THE UPPER LEVEL TROUGH WILL ATTEMPT TO MOVE EAST OF THE
REGION ON SATURDAY BUT ANOTHER STORM SYSTEM WILL LIKELY DIVE INTO
THE GREAT LAKES ON SUNDAY. THE DIFFERENCE WITH THIS STORM SYSTEM IS
THAT IT WILL ORIGINATE OVER CANADA. THIS WILL MEAN COOLER
TEMPERATURES FOR SUNDAY.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
WILL HAVE A WARM FRONT PUSHING NORTH ACROSS THE AREA TONIGHT/EARLY
MONDAY MORNING. THIS WILL BRING SOME SHOWERS TO THE TAF
SITES AND A PERIOD OF MVFR CIGS/VSBY WITH THOSE SHOWERS IN THE
MORNING. OTHERWISE A MIX OF VFR AND MVFR TONIGHT. FOR THE SECOND
HALF OF THE NIGHT SHOWERS WILL MOVE INTO THE AREA...SPREADING FROM
SOUTHWEST TO NORTHEAST AFTER 08Z. ALL SITES WILL HAVE SOUTH WINDS
BY MORNING WITH GUSTS AROUND 20 KNOTS FOR THE DAYTIME MONDAY...A
LITTLE SOONER AT KERI. VFR MOST LIKELY FOR MONDAY AFTERNOON.
.OUTLOOK...NON VFR IN SHOWERS AND THUNDERSTORMS TUESDAY INTO
WEDNESDAY...POSSIBLY LINGERING INTO THURSDAY.
&&
.MARINE...
HIGH PRESSURE IS EAST OF THE REGION. THIS WILL ALLOW FOR AN
INCREASING SOUTHERLY FLOW INTO MONDAY AS LOW PRESSURE DEEPENS OVER
THE MIDDLE MISSISSIPPI RIVER VALLEY. THIS AREA OF LOW PRESSURE WILL
ONLY SLOWLY MOVE NORTHEASTWARD AND MAY REACH THE CENTRAL GREAT LAKES
BY WEDNESDAY AFTERNOON. WINDS WILL REMAIN SOUTH TO SOUTHWEST THROUGH
THE WEEK BUT THERE IS GREAT UNCERTAINTY ON THE TRACK OF THE SURFACE
LOW. WINDS WILL LIKELY BE THE STRONGEST ON TUESDAY AHEAD OF A
FRONTAL BOUNDARY THAT SHOULD BE EAST OF THE LAKE AT SOME POINT
TUESDAY NIGHT. WINDS MAY INCREASE ENOUGH TO NEED A SMALL CRAFT
ADVISORY ON TUESDAY UNTIL THE FRONTAL BOUNDARY PASSES. THE UPPER
LEVEL LOW WILL CONTINUE TO WOBBLE OVER THE GREAT LAKES REGION
THURSDAY INTO FRIDAY WITH WINDS INCREASING AHEAD OF EACH PIECE OF
ENERGY THAT ROTATES AROUND IT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...TK/LOMBARDY
SHORT TERM...LOMBARDY
LONG TERM...MULLEN
AVIATION...OUDEMAN
MARINE...MULLEN
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
747 PM EDT SUN OCT 12 2014
.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST AND OFF THE EASTERN SEABOARD BY MONDAY
MORNING. LOW PRESSURE WILL MOVE NORTHEAST INTO THE CENTRAL GREAT
LAKES BY WEDNESDAY. A TROUGH OF LOW PRESSURE WILL MOVE EAST ACROSS
THE AREA ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
UPDATE...ADJUSTED POPS UP A BIT BASED ON HRRR AND NAM/GFS ADVANCE
OF RH AND UVV INTO THE AREA OVERNIGHT. PRECIP ALREADY
DEVELOPING/MOVING INTO WRN/SRN INDIANA AND KY.
ORIGINAL...MODELS HAVE BEEN A BIT FAST WITH THE PRECIPITATION AS
IT MOVES NORTHEAST TOWARD THE AREA. MOISTURE WILL STREAM NORTHEAST
TOWARD THE REGION OVERNIGHT BUT WILL HAVE A DIFFICULT TIME
ENCOUNTERING THE DRY AIR OVER THE REGION AT THIS TIME. SATELLITE
DATA SHOWS CLOUDS MOVING NORTHEAST AT THIS TIME INTO SOUTHWEST
OHIO STRUGGLING TO MAKE ANY HEADWAY. TIMING AS OF NOW WILL BE TO
MOVE AT LEAST A CHANCE FOR SHOWERS INTO THE SOUTHWEST CORNER OF
THE FORECAST AREA BY THIS EVENING AND TO CLEVELAND AND MANSFIELD
BY 11Z AND TO ERIE AND YOUNGSTOWN BY 14Z. INCREASING CLOUDINESS
WILL TAKE PLACE OVERNIGHT AS WELL.
TEMPERATURES IN THE SREF AND LOCAL MODEL HAVE BEEN DOING WELL SO FAR
AND WILL BE LEANING IN THAT DIRECTION FOR OVERNIGHT LOWS. WARM AIR
ADVECTION WILL TAKE PLACE OVERNIGHT AND LOWS WILL NOT BE ANY WHERE
NEAR THE LOWS THIS MORNING.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
DEEP DIGGING UPPER LEVEL LOW PRESSURE WILL MOVE EAST ACROSS THE AREA
OVER THE NEXT FEW DAYS. THIS FEATURE WILL REFLECT A LOW PRESSURE
SYSTEM AT THE SURFACE AND TRACK IT NORTHEAST THROUGH THE CENTRAL
GREAT LAKES. THIS IS INDICATIVE OF A TYPICAL FALL PATTERN AS LOWS
TEND TO TRACK IN A SIMILAR FASHION. MANY DIFFERENCES IN THE MODELS
IN TIMING OF THE PRECIPITATION. THE BOTTOM LINE IS THAT IT IS GOING
TO RAIN AT SOME POINT BETWEEN MONDAY AND WEDNESDAY NIGHT. WE
ACTUALLY SEE A COUPLE SURGES OF DRIER AIR ALTERNATING WITH MOISTURE
SURGES SO THERE COULD BE PERIODS OF NO PRECIPITATION. WILL TRY AND
HIGHLIGHT THE BETTER CHANCES FOR THE PRECIPITATION THREATS THROUGH
THIS PERIOD. AS THE UPPER LEVEL LOW MOVES IN OVER THE REGION ALONG
WITH THE PRE FRONTAL TROUGH AND COLD FRONT...THUNDER IS A
POSSIBILITY AND WILL KEEP AT LEAST A CHANCE OR ISOLATED THREAT FOR
THUNDERSTORMS.
WARM AIR ADVECTION WILL DEVELOP WELL AHEAD OF THE LOW PRESSURE
SYSTEM AND IN THE WAKE OF THE HIGH. THIS ALONE WILL HELP TO FORCE
SOME WARMER AIR INTO THE REGION. IF WE DO GET SOME BREAKS OF SUN
TOMORROW AND TUESDAY...TEMPERATURES WILL INDEED BE WELL INTO THE 70S
EACH DAY. WILL STAY IN THE MIDDLE OF THE ROAD FOR GUIDANCE MAX
TEMPERATURES. COLD AIR ADVECTION TAKES PLACE WEDNESDAY WITH THE
PASSAGE OF THE COLD FRONT.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
NOT MUCH CONFIDENCE IN THE TIMING OF RAINFALL ACROSS THE AREA
THROUGH THE LONG TERM AS AN UPPER LEVEL LOW PRESSURE WOBBLES OVER
THE REGION. THE UPPER LEVEL LOW MOVEMENT WILL LIKELY BE CLOSER IN
TIMING TO THE ECMWF. TEMPERATURES THURSDAY INTO FRIDAY LOOK LIKE
THEY WILL BE NEAR SEASONAL LEVELS BUT IT WILL ALL HINGE ON THE
AMOUNT OF CLOUD COVER THAT DEVELOPS UNDER THE COLD CORE OF AIR
ALOFT. THE UPPER LEVEL TROUGH WILL ATTEMPT TO MOVE EAST OF THE
REGION ON SATURDAY BUT ANOTHER STORM SYSTEM WILL LIKELY DIVE INTO
THE GREAT LAKES ON SUNDAY. THE DIFFERENCE WITH THIS STORM SYSTEM IS
THAT IT WILL ORIGINATE OVER CANADA. THIS WILL MEAN COOLER
TEMPERATURES FOR SUNDAY.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
WILL HAVE A WARM FRONT PUSHING NORTH ACROSS THE AREA TONIGHT/EARLY
MONDAY MORNING. THIS WILL BRING SOME SHOWERS TO THE TAF
SITES AND A PERIOD OF MVFR CIGS/VSBY WITH THOSE SHOWERS IN THE
MORNING.
LARGELY VFR TO START THE NIGHT. SOME MVFR CEILINGS FOR
MFD/BJJ/CAK TO START THE EVENING...BUT DECENT CONFIDENCE THAT
THIS WILL BECOME MORE ISOLATED OVER THE NEXT FEW HOURS. FOR THE
SECOND HALF OF THE NIGHT SHOWERS WILL BRING DIPS DOWN TO MVFR. THE
SHOWERS WILL SPREAD FROM SOUTHWEST TO NORTHEAST AFTER 08Z. ALL
SITES WILL HAVE SOUTH WINDS BY MORNING WITH GUSTS AROUND 20 KNOTS
FOR THE DAYTIME MONDAY...A LITTLE SOONER AT KERI. VFR MOST LIKELY
FOR MONDAY AFTERNOON.
.OUTLOOK...NON VFR IN SHOWERS AND THUNDERSTORMS TUESDAY INTO
WEDNESDAY...POSSIBLY LINGERING INTO THURSDAY.
&&
.MARINE...
HIGH PRESSURE IS EAST OF THE REGION. THIS WILL ALLOW FOR AN
INCREASING SOUTHERLY FLOW INTO MONDAY AS LOW PRESSURE DEEPENS OVER
THE MIDDLE MISSISSIPPI RIVER VALLEY. THIS AREA OF LOW PRESSURE WILL
ONLY SLOWLY MOVE NORTHEASTWARD AND MAY REACH THE CENTRAL GREAT LAKES
BY WEDNESDAY AFTERNOON. WINDS WILL REMAIN SOUTH TO SOUTHWEST THROUGH
THE WEEK BUT THERE IS GREAT UNCERTAINTY ON THE TRACK OF THE SURFACE
LOW. WINDS WILL LIKELY BE THE STRONGEST ON TUESDAY AHEAD OF A
FRONTAL BOUNDARY THAT SHOULD BE EAST OF THE LAKE AT SOME POINT
TUESDAY NIGHT. WINDS MAY INCREASE ENOUGH TO NEED A SMALL CRAFT
ADVISORY ON TUESDAY UNTIL THE FRONTAL BOUNDARY PASSES. THE UPPER
LEVEL LOW WILL CONTINUE TO WOBBLE OVER THE GREAT LAKES REGION
THURSDAY INTO FRIDAY WITH WINDS INCREASING AHEAD OF EACH PIECE OF
ENERGY THAT ROTATES AROUND IT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...TK/LOMBARDY
SHORT TERM...LOMBARDY
LONG TERM...MULLEN
AVIATION...OUDEMAN
MARINE...MULLEN
SHORT TERM FORECAST DISCUSSION. BY TUESDAY NIGHT...THE FRONT SHOULD
BE NEAR THE ERN ILN CWA...WITH A DRY SLOT MOVING INTO THE REGION
FROM THE SOUTHWEST. THE UPPER TROUGH IS EXPECTED TO SLOW DOWN AND
CLOSE OFF OVER THE MID- MISSISSIPPI VALLEY...WITH IMPACTS MOVING
INTO THE ILN CWA BY WEDNESDAY. COLD AIR ALOFT AND FORCING FROM THE
TROUGH WILL NECESSITATE 30-50 PERCENT CHANCES FOR RAIN THROUGH
WEDNESDAY...WITH POPS NOW PERSISTING IN THE FORECAST INTO
THURSDAY...ENDING THURSDAY EVENING. TIMING FOR THESE FEATURES IS
BASED ON AN APPROXIMATION OF THE 12Z GFS / 00Z ECMWF
TIMING...WHICH SEEMS THE BEST COMPROMISE BETWEEN MODELS. AMONG THE
OUTLIERS ARE THE 12Z ECMWF (SLOW AND AMPLIFIED) AND 12Z CANADIAN
(FAST AND WITHOUT A CLOSING OF THE UPPER LOW).
ASIDE FROM POPS...ADJUSTMENTS WERE ALSO MADE TO SKY GRIDS (WITH VERY
CLOUD CONDITIONS EXPECTED THROUGH THURSDAY NIGHT) AND TEMPERATURES
(LIMITING THE DIURNAL CURVE THROUGH FRIDAY). THIS RESULTED IN A
DECREASE IN THE MAX TEMP FORECAST OF SEVERAL DEGREES ON THURSDAY.
WHILE THE FORECAST STILL ALLOWS FOR WARMING BACK TO VALUES NEAR
NORMAL ON FRIDAY...THIS IS OBVIOUSLY DEPENDENT ON THE SYSTEM MOVING
OUT OF THE OHIO VALLEY BY THEN.
ONCE THE SYSTEM FINALLY DOES CLEAR OUT OF THE AREA...A DRY PATTERN
IS EXPECTED OVER THE WEEKEND. UPPER FLOW WILL TURN MORE ZONAL...WITH
HIGH PRESSURE OVER THE CENTRAL STATES DRIFTING EAST INTO THE OHIO
AND TENNESSEE VALLEY REGIONS.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
WITH HIGH PRESSURE IN PLACE...CIRRUS DECK IS EXPECTED TO SHIFT
EASTWARD AND GRADUALLY ERODE OVERNIGHT ESPECIALLY OVER THE
NORTHERN TAF SITES WHERE SKIES WILL LIKELY BECOME MOSTLY CLEAR.
VFR CONDITIONS WILL CONTINUE WITH THE EXCEPTION OF KLUK WHERE
SOME SHALLOW FOG MAY DEVELOP AFTER 07Z. WINDS WILL SHIFT FROM THE
NORTHEAST TONIGHT TO THE SOUTHEAST BY SUNDAY AFTERNOON. WILL SEE A
LOWERING IN CIGS FROM SOUTH TO NORTH BEGINNING AROUND DAYBREAK ON
SUNDAY AND CONTINUING THROUGH THE MORNING AS DEEPER MOISTURE
CREEPS FURTHER NORTH. CIGS ARE EXPECTED TO REMAIN VFR BUT SOME
MODEL GUIDANCE IS SUGGESTING THE POSSIBILITY OF MVFR CIGS
TOWARDS THE END OF THE TAF PERIOD. ISOLATED SHOWERS MAY DEVELOP
SUNDAY AFTERNOON AND EVENING AS WARM MOIST AIR STREAMS INTO THE
AREA SO HAVE INCLUDED VCSH AT ALL SITES. KCVG AND KLUK WILL HAVE
THE GREATEST POTENTIAL OF SEEING SCATTERED SHOWERS BY SUNDAY
EVENING SO WENT WITH -SHRA AT THOSE TERMINALS. MORE FAVORABLE
FORCING FOR SHOWERS AND PERHAPS A FEW THUNDERSTORMS WILL HOLD OFF
UNTIL SUNDAY NIGHT.
.OUTLOOK...THUNDERSTORMS AND MVFR CIGS ARE POSSIBLE FROM SUNDAY
THROUGH MONDAY NIGHT.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...FROST ADVISORY FROM 2 AM TO 9 AM EDT SUNDAY FOR OHZ026-034-035-
042>046-051>056-064-065-074.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HICKMAN
NEAR TERM...HICKMAN
SHORT TERM...HICKMAN
LONG TERM...HATZOS/HICKMAN
AVIATION...KURZ
AREA FORECAST DISCUSSION
NWS TULSA OK
1151 PM CDT FRI OCT 10 2014
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
IFR CONDITIONS IN SHOWERS / SCATTERED THUNDER MOVING ACROSS
TAF AREA OVERNIGHT. IFR/LOW MVFR CONDITIONS SATURDAY WITH
MORE SHOWERS POSSIBLE THUNDER LIKELY TO REDEVELOP. TAF SITE
KBVO MAY REMAIN NORTH OF PRECIP AND LOWER CONDITIONS.
&&
.PREV DISCUSSION... /ISSUED 802 PM CDT FRI OCT 10 2014/
UPDATE...
POPS HAVE BEEN ADJUSTED FOR TONIGHT...MAINLY CONFINING THE HIGHEST
POPS IN THE SOUTH. SEE DISCUSSION BELOW.
DISCUSSION...
THE SURFACE FRONT HAS SUNK DOWN INTO SOUTHEAST OKLAHOMA THIS
EVENING...AND WILL CONTINUE TO SLOWLY SAG SOUTH TOWARD THE RED
RIVER. STABILIZATION HAS TAKEN PLACE WELL NORTH OF THE FRONT
ACROSS NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS. ELEVATED STORMS
CONTINUE ACROSS CENTRAL AND SOUTHEAST OKLAHOMA WHERE THE ELEVATED
INSTABILITY LIES. ACTIVITY OVER CENTRAL OKLAHOMA SHOULD WEAKEN AS
IT TRACKS INTO THE MORE STABLE AIR OVER NE OK AND NW AR...THUS
THIS CASTS SOME DOUBT AS TO WHETHER THERE IS ANY FLOODING
POTENTIAL FOR NW AR TO KEEP THE FLASH FLOOD WATCH GOING. WILL WAIT
ON SOME NEW 00Z NAM AND HRRR DATA BEFORE MAKING FINAL DECISION. I
HAVE CUT WAY BACK ON POPS ALONG AND NORTH OF I-44 AND MAY CUT POPS
BACK OVER NW AR IF THE TRENDS CONTINUE.
LACY
PREV DISCUSSION... /ISSUED 650 PM CDT FRI OCT 10 2014/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
SHOWERS/SCATTERED THUNDERSTORMS PRIMARILY SOUTHEAST OK
AND WEST CENTRAL AR TAF SITES KMLC KFSM THIS EVENING INTO
OVERNIGHT. LOW MVFR CEILING KBVO...IFR CEILINGS KTUL KRVS
KXNA KFYV SLOWLY RISING THEN HOLDING AROUND 10-15 HND FEET
OVERNIGHT. SLOW IMPROVEMENT SATURDAY FROM THE NORTH WITH
GENERALLY MVFR CEILINGS.
PREV DISCUSSION... /ISSUED 326 PM CDT FRI OCT 10 2014/
DISCUSSION...
SURFACE BASED THUNDERSTORMS ARE OCCURRING THIS AFTERNOON ALONG A
FRONTAL BOUNDARY THAT EXTENDS FROM AN AREA OF LOW PRESSURE NEAR
KADM TO NEAR KMLC AND INTO WEST-CENTRAL ARKANSAS. SOME OF THESE
STORMS ACROSS SOUTHEAST OKLAHOMA COULD BECOME STRONG TO SEVERE
WITH SURFACE BASED CAPE AROUND 1500 J/KG AND LI VALUES AROUND
-5. LARGE HAIL AND WIND GUST TO AROUND 65 MPH WILL BE THE MAIN
CONCERN. THE SEVERE THREAT WILL DIMINISH THIS EVENING AS THE
CONVECTION BECOMES MORE ELEVATED. LOCALLY HEAVY RAIN IS ALSO A
CONCERN WITH THESE STORMS. 1 TO 2 INCHES OF RAIN WILL BE POSSIBLE
WHICH COULD LEAD TO LOCALIZED FLOODING OF LOW LYING AREAS. ADDITIONAL
SHOWERS AND THUNDERSTORM WILL CONTINUE TO BE POSSIBLE OVERNIGHT AND
INTO SATURDAY AS SEVERAL MID-LEVEL SHORTWAVES MOVE ACROSS THE AREA
AND AS THE FRONTAL BOUNDARY SLOWLY MOVES SOUTH AND EAST OF THE AREA.
STILL A CONCERN ABOUT FLASH FLOODING IN THE FAR NORTHWEST ARKANSAS COUNTIES
AS THE GROUND ACROSS THAT AREA IS ALREADY SATURATED. SOME LOCATIONS IN
NORTHWEST ARKANSAS COULD SEE 1 TO 2 INCHES OF RAIN WHICH COULD POSE A
FLASH FLOOD CONCERN. WILL LEAVE THE FLASH FLOOD WATCH IN PLACE FOR TONIGHT
FOR THE NORTHWEST ARKANSAS COUNTIES WHILE DROPPING THE NORTHEAST OKLAHOMA
COUNTIES WHERE LESSER RAIN FALL AMOUNTS ARE ANTICIPATED. THE SHOWERS AND
THUNDERSTORMS ARE EXPECTED TO COME TO AN END SATURDAY NIGHT AS THE MAIN
SHORTWAVE CURRENTLY OVER THE SOUTHWEST UNITED STATES MOVES EAST OF THE
TULSA FORECAST AREA.
THE NEXT CHANCE OF SHOWERS AND THUNDERSTORMS WILL BE SUNDAY NIGHT INTO
MONDAY AS A STRENGTHENING MID-LEVEL SHORTWAVE MOVES OUT OF THE ROCKIES
AND ACROSS THE AREA. THE ASSOCIATED COLD FRONT WILL MOVE THROUGH THE
REGION LATE SUNDAY NIGHT INTO MONDAY MORNING. STRONG TO SEVERE THUNDERSTORMS
WILL ALSO BE POSSIBLE WITH THIS SYSTEM. A SQUALL LINE OF STRONG TO SEVERE
THUNDERSTORMS WILL BE POSSIBLE ALONG THE FRONT AS IT MOVES ACROSS
PORTIONS EASTERN OKLAHOMA AND INTO WESTERN ARKANSAS. THE ACTIVITY IS EXPECTED
TO END MONDAY NIGHT AS THE MID-LEVEL SHORTWAVE MOVES EAST OF THE AREA.
THE REMAINDER OF THE FORECAST IS DRY AS A MID-LEVEL RIDGE DEVELOPS OVER
THE AREA. THE NEXT FRONT IS EXPECTED TO COME THROUGH THE AREA DRY ON
FRIDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 49 58 46 73 / 30 40 10 20
FSM 61 64 53 73 / 90 60 30 20
MLC 52 60 47 74 / 90 40 20 20
BVO 50 58 44 72 / 20 30 10 20
FYV 51 58 47 69 / 50 60 30 20
BYV 48 56 46 68 / 50 70 30 20
MKO 52 58 48 71 / 50 50 20 20
MIO 48 57 46 70 / 20 40 20 20
F10 50 58 47 73 / 70 40 10 20
HHW 60 66 52 74 / 90 40 20 20
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...FLASH FLOOD WATCH UNTIL 7 AM SATURDAY FOR OKZ073-OKZ075-OKZ076.
AR...FLASH FLOOD WATCH UNTIL 7 AM SATURDAY FOR ARZ001-ARZ002-ARZ010-
ARZ011-ARZ019-ARZ020-ARZ029.
&&
$$
SHORT TERM...18
LONG TERM....18
AVIATION...21
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
434 PM EDT SAT OCT 11 2014
.SYNOPSIS...
A BACK DOOR COLD FRONT WILL PUSH THROUGH THE AREA TONIGHT...WITH A
COOL WEDGE OF HIGH PRESSURE BUILDING IN BEHIND THE FRONT FOR SUNDAY.
THE FRONT WILL BEGIN TO LIFT BACK NORTH AS A WARM FRONT MONDAY AHEAD
OF A STRONG COLD FRONT...WHICH WILL CROSS THE REGION TUESDAY. DRY
HIGH PRESSURE WILL THEN RETURN FOR THE LATTER HALF OF THE WEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
415 PM UPDATE...CLUSTER OF TSTMS NOW MOVING THRU THE CHARLOTTE METRO
IS ASSOCIATED WITH A SHORTWAVE OVER THAT AREA...WHICH SHOULD MOVE
OFF TO THE EAST OVER THE NEXT COUPLE HRS. NO SUCH DISTURBANCES ARE
SEEN OVER THE WRN PART OF THE AREA IN WV IMAGERY OR ON RUC 500MB
ANALYSIS...AND DESPITE 1000 J OR MORE OF CAPE SEEN ON SPC
MESOANALYSIS OVER THE CENTRAL CWFA THAT AREA IS LARGELY DEVOID OF
EVEN SHALLOW CUMULUS. LESS IMPRESSIVE LINE OF SHOWERS WITH EMBEDDED
TSTMS IS OVER THE EAST TENN FOOTHILLS...THIS EVIDENTLY BEING FORCED
BY THE APPROACHING COLD FRONT. GUIDANCE SUPPORTS BOTH THE DEPARTURE
OF THE CHARLOTTE ACTIVITY LATE THIS AFTN AND A SLIGHT INCREASE IN
POPS OVER THE MTNS THRU THE EVENING AS THE FRONT IMPINGES. IN
GENERAL HOWEVER POP VALUES HAVE BEEN REDUCED INTO THE EARLY EVENING.
FOR THE OVERNIGHT...THE MODELS ARE CONSISTENT IN BACKDOORING A COLD
FRONT THROUGH THE AREA. WINDS WILL SHIFT TO THE NE WITH CAD SCENARIO
DEVELOPING BY SUNRISE ON SUNDAY. AS ISENTROPIC LIFT DEVELOPS OVER
THE CAD...SOME LIGHT RAIN SHOWERS ARE EXPECTED TO DEVELOP OVERNIGHT
AND PERSIST ON SUNDAY...PARTICULARLY ALONG THE BLUE RIDGE AND THE
WESTERN UPSTATE COUNTIES. TEMPS WILL BEGIN TO COOL OVERNIGHT BEHIND
THE FRONT...BUT STILL REMAIN ABOVE CLIMO. ON SUNDAY WITH THE CAD...
WILL CONTINUE TO USE CONSRAW FOR TEMP FIELDS WHICH KEEPS MAX TEMPS A
CATEGORY OR SO BELOW CLIMO.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH WEDNESDAY NIGHT/...
AS OF 250 PM SATURDAY...MONDAY MORNING...MID LEVEL HEIGHTS ACROSS
THE REGION WILL BEGIN TO FALL...AS A RIDGE REMAINS OVER THE WESTERN
ATLANTIC AND A DEEP TROUGH OR CLOSED LOW AMPLIFIES ACROSS THE
PLAINS. AT THE SFC...RIDGING WILL REMAIN ACROSS THE WESTERN
CAROLINAS...SOURCED FROM A MID ATLANTIC HIGH. ONGOING ISENTROPIC
LIFT AND UPSLOPE FLOW SHOULD SUPPORT NUMEROUS SHRA ACROSS THE EAST
FACING SLOPES...WITH SCT COVERAGE EAST. TEMPERATURES ARE FORECAST TO
GENERALLY RANGE IN THE MID 50S TO NEAR 60.
ON MONDAY...LINGERING AREA OF COLD AIR DAMMING SHOULD ERODE THROUGH
THE DAY...BECOMING MORE LIMITED TO THE FOOTHILL AREAS. UPSLOPE FLOW
AND WEAK ELEVATED INSTABILITY SHOULD CONTINUE TO SUPPORT SHOWERS
ACROSS THE MTNS...WITH TS EAST. OVERALL...COVERAGE OF CONVECTION IS
EXPECTED TO REMAIN IN THE CHC RANGE. HIGH TEMPERATURE PATTERN WILL
REFLECT A LINGERING WEDGE OF HIGH PRESSURE...WITH 60S ACROSS THE
UNIFOUR AND UPPER 70S ACROSS PORTIONS OF THE UPPER SAVANNAH RIVER
VALLEY.
ON TUESDAY...SHORT RANGE GUIDANCE HAS TRENDED SLOWER FROM RUNS
YESTERDAY. HOWEVER...AGREEMENT BETWEEN GUIDANCE IS FAIR WITH THE
TIMING AND PLACEMENT OF MAIN FEATURES...I WILL USE A BLEND OF THE
NAM AND GFS. BY 12Z TUESDAY...THE SFC COLD FRONT IS FORECAST TO RUN
FROM MIDDLE KY/TN SOUTH TO ALONG THE GA/AL LINE. THE NAM WIND FIELDS
INDICATE THAT A LLVL JET WILL BEGIN TO ENCOUNTER THE MTNS AROUND
12Z...WITH H85 WINDS AROUND 50 KTS THROUGH 18Z. I WILL INCREASE
RIDGETOP WINDS...FEATURING MARGINAL WIND ADVISORY GUSTS. DURING THE
DAYLIGHT HOURS...THE GFS INDICATES A CLOSED LOW OVER THE MID WEST
WITH THE TROF AXIS SWEEPING EAST ACROSS THE DEEP SOUTH. Q-VECTOR
CONVERGENCE INCREASES SHARPLY DURING THE LATE MORNING AND REMAINS
INTO THE EVENING. AT THE LLVLS...THE ENVIRONMENT ALONG AND AHEAD OF
THE COLD FRONT WILL FEATURE VERY STRONG SHEAR AND HELICITY
VALUES...WITH PIEDMONT AREAS UNDER 0-1 KM HELICITY VALUES FROM
300-400 M2/S2. INSTABILITY WILL REMAIN THE LIMITING
FACTOR...HOWEVER...NAM FORECAST SOUNDINGS INDICATE THAT PIEDMONT
AREAS COULD SEE VALUES RISE ABOVE 500 J/KG BY MID DAY. THIS FORECAST
PACKAGE DOES HAVE THE BENEFIT OF VIEWING THE SIMULATED REFLECTIVITY
FROM THE NAM. THE NAM SHOWS A WELL ORGANIZED QLCS REACHING THE NC
MTNS AROUND 15Z...GSP AREA BETWEEN 18Z-0Z...THEN CLT BETWEEN 0Z-3Z.
SHERB AND EHI VALUES BETWEEN 0-3 KM INDICATE A RIPE HIGH SHEAR LOW
CAPE ENVIRONMENT FOR WIND OR ISO TORNADOES. IN ADDITION...ABOVE
SEASONABLE VALUES OF PW AND MID TO UPPER 30S K-INDEX INDICATE THE
POTENTIAL FOR HEAVY RAIN. FLASH FLOODING WILL BE A CONCERN ACROSS
THE CWA. COVERAGE SHOULD PUSH EAST TUESDAY NIGHT...LEAVING SOME
UPSLOPE SHOWERS ACROSS THE TN/NC LINE THROUGH THE NIGHT.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 200 PM SATURDAY...THERE IS STILL QUITE A BIT OF SPREAD AMONG
THE MEDIUM RANGE GUIDANCE WITH HOW THE KEEP TROF/CLOSED UPR LOW WILL
EVOLVE WED-FRI. THE ECWMF HAS BEEN CONSISTENTLY THE DEEP/SLOW
OUTLIER...WHILE THE GFS IS MORE PROGRESSIVE ALTHO TRENDING TOWARD
THE ECMWF THE LAST FEW CYCLES. I STARTED WITH THE SUPERBLEND...WHICH
TRENDS A LITTLE SLOWER ON CLEARING OUT THE WRAP-AROUND
MOISTURE/SHWRS WED INTO THU (A COMPROMISE BETWEEN THE GFS AND
ECMWF). OTHERWISE...NO SIGNIFICANT CHANGES FROM PREVIOUS FCST.
AS ALLUDED TO ABOVE...EVEN THE FASTER SOLNS WITH THE UPR LOW HAVE NW
FLOW/UPSLOPE SHWR ACTIVITY DURING THE DAY ON WED. I BUMPED UP
COVERAGE OF CHC POP IN THE NC MTNS...WITH SLGT CHC POP ALL THE WAY
TO THE FOOTHILLS. SLGT CHC POP LINGERS IN THE MTNS INTO THU.
OTHERWISE...EXPECT SLIGHTLY BELOW NORMAL TEMPS WED...THEN A GRADUAL
WARMING TREND TO SLIGHTLY ABOVE NORMAL TEMPS BY FRI/SAT. ONCE THE
UPR LOW LIFTS NE OF THE AREA...MOSTLY CLEAR SKIES AND DRY CONDITIONS
ARE EXPECTED...WITH HIGH PRES BUILDING IN UNDER FLATTENING UPR FLOW.
&&
.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
AT KCLT...IN THE NEAR TERM...THE CONCERN IS FOR THUNDERSTORMS. LAST
ACTIVITY IS EXPECTED TO DEPART THE AREA BETWEEN 2100 AND 2130 UTC.
IFR VSBY LIKELY IF A CELL PASSES RIGHT OVER THE FIELD WITH MAINLY
WESTERLY GUSTS. HAVE INCLUDED A TEMPO ON THESE ACCOUNTS. TONIGHT...A
BACKDOOR COLD FRONT WILL PUSH THROUGH SHIFTING WINDS TO THE NE. A
MOIST BOUNDARY LAYER WILL COOL BEHIND THE FRONT ALLOWING FOR
LOWERING CLOUDS WHICH WILL BECOME IFR TOWARD SUNRISE WITH ONLY VERY
SLOW IMPROVEMENT THROUGH SUNDAY MORNING.
ELSEWHERE...SIMILAR TO CLT IN THAT THE NEAR TERM CONCERN IS FOR
THUNDERSTORMS. WILL ADVERTISE TEMPO TSRA AT ALL AIRFIELDS EXCEPT
KAVL FROM 19-23Z. KAVL COULD SEE A STORM BUT CONFIDENCE NOT HIGH
ENUF EXCEPT FOR VCTS. AFTER THAT...A BACKDOOR COLD FRONT WILL PUSH
THROUGH SHIFTING WINDS TO THE NE. A MOIST BOUNDARY LAYER WILL COOL
BEHIND THE FRONT ALLOWING FOR LOWERING CLOUDS WHICH WILL BECOME IFR
MOST AREAS TOWARD SUNRISE WITH ONLY VERY SLOW IMPROVEMENT THROUGH
SUNDAY MORNING.
OUTLOOK...RESTRICTIONS WILL CONTINUE IN A MOIST AIR MASS THROUGH
MONDAY. A STRONG COLD FRONT ARRIVING TUESDAY WILL BRING A THREAT OF
VERY HEAVY RAIN AND POSSIBLY DAMAGING WIND GUSTS...FOLLOWED BY
DRYING.
CONFIDENCE TABLE...
20-02Z 02-08Z 08-14Z 14-20Z
KCLT HIGH 95% HIGH 84% HIGH 90% HIGH 95%
KGSP HIGH 100% HIGH 87% MED 79% HIGH 85%
KAVL HIGH 100% MED 77% MED 71% LOW 58%
KHKY HIGH 100% HIGH 81% HIGH 86% HIGH 90%
KGMU HIGH 100% HIGH 88% HIGH 80% HIGH 85%
KAND HIGH 100% HIGH 94% MED 69% MED 77%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...ARK
NEAR TERM...LG/WIMBERLEY
SHORT TERM...NED
LONG TERM...ARK
AVIATION...LG/WIMBERLEY
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
730 PM CDT SUN OCT 12 2014
.UPDATE...
00Z TAF DISCUSSION.
&&
.AVIATION...
OTHER THAN A FEW -SHRA NEAR CSV...PRECIP HAS GENERALLY WANED
ACROSS THE MID STATE ATTM. ANOTHER WAVE WILL MOVE ACROSS
OVERNIGHT...BUT MAJORITY OF PRECIP MAY PASS WEST OF AREA AIRPORTS
AND WILL JUST MENTION VCSH FOR NOW. VFR CONDITIONS SHOULD PREVAIL
AT CKV/BNA...BUT CIGS/VIS WILL LIKELY GO IFR AT CSV. ALL AIRPORTS
WILL SEE VFR CONDITIONS DURING THE DAY ON MONDAY WITH GUSTY SOUTH
WINDS UP TO 25 KTS.
SHAMBURGER
&&
.PREV DISCUSSION... /ISSUED 330 PM CDT SUN OCT 12 2014/
DISCUSSION...
PARTLY TO MOSTLY CLOUDY SKIES ARE IN PLACE ACROSS THE MID STATE
THIS AFTERNOON. THE BULK OF THE CLOUD COVER...HOWEVER...IS LOCATED
ACROSS SOUTHERN AREAS WHERE A COMPLEX OF SHOWER AND TSTM ACTIVITY
IS ONGOING...GENERALLY SOUTH OF A LEWISBURG THROUGH MANCHESTER
LINE AT 130 PM. THIS ACTIVITY IS IN RESPONSE TO A WARM FRONT THAT
IS CURRENTLY POSITIONED ACROSS NRN AL. ON THE SFC CHARTS DEWPOINTS
HAVE WARMED WELL INTO THE 60S ACROSS OUR AREA. THERE IS A WEAK SFC
BOUNDARY THAT LIFTED NORTHWARD EARLIER TODAY AND IS NOW LOCATED
OVER KY. AT ANY RATE...CONVECTION WILL CONTINUE TO FIRE ALONG AND
AHEAD OF THE NORTHWARD MOVING BOUNDARY. WE SHOULD SEE CONVECTION
INCREASE IN COVERAGE AND INTENSITY THROUGH THE EVENING HOURS. A
FEW OF THE STORMS COULD BECOME STRONG. OTW...MODELS APPEAR TO BE
BIT TOO HIGH WITH THE POPS AGAIN. WILL INCLUDE POPS IN THE LIKELY
RANGE AS HRRR DOES SHOW SOME REDEVELOPMENT TOWARD 12Z.
ON MONDAY...PRESSURE GRADIENT WILL BE ON THE INCREASE AS THE MAIN
STORM SYSTEM OVER THE PLAINS STATES BEGINS TO GAIN STRENGTH.
CONSIDERED A WIND ADVISORY BUT EURO AND NAM SOLUTIONS DONT QUITE
SUPPORT THE REQUIRED 20 TO 30 MPH RANGE AND WILL THEREFORE PUNT TO
THE MID SHIFT ON THE POTENTIAL ISSUANCE. FOR HIGH TEMPS...850 MB
TEMPS OF 14C-16C WILL COMBINE WITH SOME REASONABLY STRONG LATE DAY
SUBSIDENCE TO PRODUCE RATHER WARM TEMPERATURES. WILL BE GOING WITH
LOWER TO MID 80S FOR HIGHS TO THE WEST OF THE PLATEAU. NOT A WHOLE
LOT OF CONVECTION IS EXPECTED DURING THE DAY ON MONDAY. POPS WILL BE
KEPT ON THE LOW SIDE. MAINLY A BREEZY AND HUMID DAY FOR MID OCTOBER.
MONDAY EVENING...MODELS STILL IN GOOD AGREEMENT FOR A SEVERE WEATHER
EVENT. STRONG PRE FRONTAL FORCING WILL CONTINUE TO HEAD OUR WAY AND
REACH WESTERN AREAS MONDAY EVENING. THE PREFRONTAL ACTIVITY WILL
MOVE SLOWLY WEST TO EAST OVERNIGHT AND WILL TAP INTO A RATHER STRONG
65-70 KT LLJ. THUS...WIND DAMAGE IS A DISTINCT POSSIBILITY.
FURTHERMORE...HELICITY VALUES ARE SOMEWHAT AMPLIFIED AND SO THE
TORNADIC THREAT EXISTS AS WELL.
IT LOOKS AS THOUGH SOME SEVERE ACTIVITY WILL DEVELOP AHEAD OF THE
MAIN LINE...AND THIS WILL OCCUR AROUND EARLY EVENING IN OUR WESTERN
MOST COUNTIES. BUT...THE MAIN LINE OF ACTIVITY WILL REACH OUR
WESTERN MOST COUNTIES TOWARD MIDNIGHT....THEN THE NASHVILLE AREA
FROM 3 AM TO 6 AM...THEN THE PLATEAU FROM 6 AM UNTIL 9 AM TUESDAY
MORNING. POPS OF COURSE WILL BE CATEGORICAL AND WILL INCLUDE SEVERE
WEATHER WORDING. ADDITIONALLY...FLOODING WILL BE A CONCERN GIVEN THE
MAGNITUDE OF FORCING AND THE RATHER LOW FFG VALUES. NO FLOOD WATCH
WILL BE ISSUED AT THIS TIME HOWEVER AS THE 1 HR FFG GENERALLY
EXCEEDS THE EXPECTED AVERAGE 1HR RAINFALL RATES ALONG THE LINE OF
CONVECTION.
ON TUESDAY...CONDITIONS WILL QUIET DOWN EVEN THOUGH THE MAIN SFC
BOUNDARY DOES NOT REACH THE AREA UNTIL TUES NT. THE REASON FOR THIS
IS BECAUSE THE SFC LOW WILL TRACK TOWARD THE STRONGEST WAA AREA AND
THIS WILL TAKE IT FURTHER NORTH AND THEREBY CREATE SEPARATION FROM
THE UPPER LEVEL SYSTEM TO THE SOUTH. SO THE DIRECTIONAL FORCING WILL
BE MUCH MUCH WEAKER THAN WITHIN THE PREFRONTAL AREA THAT ROARS
THROUGH LATE MONDAY NIGHT. STILL THOUGH...WILL KEEP SHOWERS(TSTMS
EARLY EAST) GOING IN THE FCST FOR TUESDAY AND INTO WEDNESDAY AS
WELL.
FOR THE REMAINDER OF THE EXTENDED FCST...DRIER AIR WILL FINALLY WIN
OUT BY THURSDAY WITH PARTLY TO MOSTLY SUNNY SKIES INTO THE WEEKEND.
TEMPERATURES TO REMAIN A LITTLE ABOVE NORMAL AS HIGHER HEIGHT VALUES
QUICKLY MOVE BACK IN BEHIND THE EXITING UPPER LEVEL TROUGH.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
55
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
949 AM EDT SAT OCT 11 2014
.DISCUSSION...
THE FORECAST APPEARS TO BE GENERALLY ON TRACK...BUT WILL MAKE A FEW
SMALL ADJUSTMENTS. THE CHANCES OF THUNDERSTORMS LOOKS LOW WITH A
FAIRLY STABLE 12Z OHX SOUNDING. FFC SHOWS BETTER INSTABILITY BUT
THAT SHOULD STAY TO OUR SOUTH BASED ON RUC DEPICTIONS OF LI AND
CAPE. WILL LOWER T-STORM MENTION TO JUST ISOLATED. POP
DISTRIBUTION LOOKS GOOD WITH LIKELY POPS SOUTH AND CENTRAL...AND
CHANCE POPS NORTH. TEMPS AND DEWPOINTS WILL BE TWEAKED UP A LITTLE
TO BRING THEM CLOSER TO OBS.
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
1154 PM CDT FRI OCT 10 2014
.AVIATION...
/00Z TAFS/ IFR CONDITIONS WILL PERSIST AT THE TERMINALS OVERNIGHT...WITH
CIGS AT 400-800 FT. PATCHY FOG AND DRIZZLE WILL LOWER VISIBILITIES TO
AROUND 2-4 MILES AT TIMES. STRATUS DECK WILL EVENTUALLY THIN SATURDAY
MORNING...WITH VFR CONDITIONS RETURNING BY AROUND 15-16Z. LIGHT
NORTHERLY WINDS WILL REMAIN AT OR UNDER 10 KTS THROUGH THE VALID TAF
FORECAST PERIOD...WITH WINDS EVENTUALLY TURNING OUT OF THE SOUTH
SATURDAY AFTERNOON.
CLK
&&
.PREV DISCUSSION... /ISSUED 936 PM CDT FRI OCT 10 2014/
UPDATE...
STRONG COLD AIR ADVECTION AND POST FRONTAL STRATUS REMAINS FIRMLY IN
PLACE ACROSS THE PANHANDLES. A DRY AND STABLE AIR MASS WILL GREATLY
LIMIT ANY ISOLATED SHOWERS OVER THE AREA...SO REMOVED THE SLIGHT
CHANCE POPS OVER THE SOUTHEASTERN TEXAS PANHANDLE FOR THE REMAINDER
OF THE NIGHT. THE 00Z KAMA RAOB INDICATES A DEEP LAYER OF LOW-LEVEL
MOISTURE AND WITH PATCHY LIGHT FOG AND DRIZZLE ALREADY BEING REPORTED
OVER THE AREA...HAVE GONE AND INSERTED A MENTION THROUGH SATURDAY
MORNING. HAVE ALSO ADJUSTED SKY COVER UP AND INCREASED LOW TEMPS OVER
THE NORTHWESTERN AREAS AS EXTENSIVE CLOUD COVER SHOULD PREVENT LOWS
FROM FALLING MUCH BELOW THE 40 DEGREE MARK.
CLK
PREV DISCUSSION... /ISSUED 723 PM CDT FRI OCT 10 2014/
AVIATION...
FOR THE 00Z TAFS...IFR CONDITIONS LIKELY TO CONTINUE OVERNIGHT AT ALL
THE TAF SITES UNTIL ROUGHLY 15Z. CEILINGS BETWEEN 500 AND 1000
FT...WITH POSSIBLE BR AND DZ LOWERING VISIBILITIES TO 4 TO 5 MILES AT
TIMES. CEILINGS SHOULD LIFT TO BRIEFLY MVFR CONDITIONS SATURDAY
MORNING BEFORE VFR CONDITIONS ARE ESTABLISHED BY 18Z AT ALL SITES.
NF
PREV DISCUSSION... /ISSUED 348 PM CDT FRI OCT 10 2014/
DISCUSSION...
WATER VAPOR LOOP AND RUC ANALYSIS SHOWS A POSITIVELY TILTED UPPER
TROUGH EXTENDING THROUGH THE CENTRAL PLAINS SOUTHWESTWARD INTO NEW
MEXICO. A COLD FRONT HAS MOVED SOUTH OF THE AREA WITH NORTH WINDS
GUSTING AROUND 30 MPH. WINDS WILL DECREASE GRADUALLY THIS EVENING AS
PRESSURE GRADIENT RELAXES. LOW STRATUS WILL PERSIST THROUGH THE NIGHT
AND LAST INTO THE MORNING BEFORE CLEARING BY LATE MORNING OR MIDDAY.
THIS WILL HELP KEEP LOW TEMPERATURES ONLY IN THE LOW TO MID 40S AT
MOST LOCATIONS. SHOWERS AND THUNDERSTORMS HAVE BEEN CONFINED TO THE
FAR SOUTHEAST PORTION OF THE AREA THIS AFTERNOON AND ISOLATED TO
SCATTERED SHOWERS WILL LINGER IN THIS AREA INTO THE EVENING.
PRECIPITATION WILL SHIFT EAST OVERNIGHT AND DRY CONDITIONS WILL OCCUR
TOMORROW. TEMPERATURES WILL BE AROUND 10 DEGREES BELOW NORMAL FOR MID
OCTOBER.
THE UPPER FLOW PATTERN WILL UNDERGO SIGNIFICANT AMPLIFICATION THIS
WEEKEND AS A STRONG MID/UPPER LEVEL TROUGH EVOLVES OVER THE PLAIN BY
SUNDAY. THIS WILL FORCE SURFACE CYCLOGENESIS OVER THE PANHANDLES
LEADING TO A COMPLICATED AND POTENTIALLY ACTIVE WEATHER DAY ON
SUNDAY AND SUNDAY NIGHT. MODELS ARE IN DECENT AGREEMENT ON
TIMING/POSITION RESULTING IN INCREASED CONFIDENCE ON WINDY
CONDITIONS. DURING THE AFTERNOON DEEP MIXING SHOULD RESULT IN PEAK
WIND GUSTS IN THE 30-40 MPH RANGE BEHIND THE EASTWARD MIXING DRYLINE
AND SOUTH OF THE SURFACE LOW TRACK.
LOW LEVEL WARM/MOIST ADVECTION AHEAD OF THE DRYLINE AND STEEP MID
LEVEL LAPSE RATES SHOULD CONTRIBUTE TO AT LEAST MARGINAL INSTABILITY
FOR A BRIEF PERIOD LATE SUNDAY AFTERNOON AND EVENING. THIS COMBINED
WITH RATHER INTENSE FRONTOGENETICAL FORCING WILL RESULT IN SOME
THUNDERSTORMS MAINLY ACROSS THE EASTERN PORTION OF THE PANHANDLES
LATE SUNDAY. DEEPER MORE INTENSE CONVECTION SHOULD BE JUST EAST OF
THE PANHANDLES WHERE MORE SIGNIFICANT LOW LEVEL THETA-E ADVECTION IS
SHOWN BY THE MODELS. NEVERTHELESS SOME UNCERTAINTY STILL EXISTS ON
THE FINER DETAILS SUCH AS THE POSITION OF THE DRYLINE AND QUALITY OF
LOW LEVEL MOISTURE RETURN WHICH HAS IMPLICATIONS FOR STORM SEVERITY.
THE FOCUS THEN SHIFTS TO POTENTIAL FOR STRONG POST FRONTAL NORTHERLY
WINDS LATER SUNDAY EVENING AND OVERNIGHT. HAVE TRENDED WIND SPEEDS UP
FOR BOTH PRE-FRONTAL AND POST-FRONTAL.
DIFFERENCES IN MEDIUM RANGE DETERMINISTIC GUIDANCE THAT APPEARS
EARLY NEXT WEEK SHOULD HAVE LITTLE IMPACT ON SENSIBLE WEATHER FOR
THE PANHANDLES. THE GFS AND GFS ENSEMBLE MEAN IS MORE PROGRESSIVE
THAN THE ECMWF AND GEM AND CONSEQUENTLY IS FASTER WITH MOVING THE
UPPER LEVEL RIDGE AXIS OVER THE AREA. ASIDE FROM SOME UNCERTAINTY IN
TEMPERATURE FORECAST...THERE ARE NO SIGNIFICANT ISSUES IN THE LONG
TERM. ABOVE NORMAL TEMPERATURES SHOULD OCCUR FOR MUCH OF NEXT WEEK
WITH DRY CONDITIONS.
BRB
FIRE WEATHER...
SUNDAY/S PATTERN WILL PROMOTE WARM/DRY AND BREEZY CONDITIONS.
AFTERNOON HUMIDITIES WILL FALL INTO THE 15-20 PERCENT RANGE OVER THE
WESTERN PANHANDLES WITH SUSTAINED WINDS APPROACHING 20 MPH /20 FT/.
HOWEVER CONTINUED MOIST/GREEN VEGETATION WITH NEAR NORMAL ERC/S
DURING THE ONGOING GROWING SEASON WILL PRECLUDE A SIGNIFICANT
WILDLAND FIRE RISK.
LINDLEY
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
05
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1210 AM MDT MON OCT 13 2014
.UPDATE...
ISSUED AT 1208 AM MDT MON OCT 13 2014
UPDATED TO DROP THE WINTER WEATHER HIGHLIGHTS AND TO ADJUST POPS
FOR THE REMAINDER OF THE MORNING. SHOWERS CONTINUE TO DIMINISH AND
LATEST SHORT TERM MODELS SHOW ACTIVITY ENDING AROUND 3 AM IN MOST
AREAS. ALSO MONITORING SOME OF THE LOWER VALLEYS AS TEMPS DROPPING
INTO THE 30S ALREADY AND MAY MAKE A BRIEF RUN AT FREEZING BY
SUNRISE.
UPDATE ISSUED AT 910 PM MDT SUN OCT 12 2014
ROAD REPORTS AND WEB CAMS SUGGEST THAT SNOW OVER VAIL PASS
CONTINUES TO HAVE IMPACT...AND THE SAME HOLDS TRUE FOR MONARCH
PASS. THE SNOW MAY HAVE STOPPED OVER RABBIT EARS BUT RADAR STILL
SHOW SHOWERS NORTH OF HIGHWAY 40 AND MOVING SOUTHWARD. WILL LET
THE WINTER WEATHER ADVISORY PLAY OUT. SNOW HAS DIMINISHED OVER THE
NWRN SAN JUAN MOUNTAINS AND HAVE ALLOWED THE ADVISORY TO EXPIRE. A
FEW FLURRIES STILL ONGOING...BUT REMOTE SENSORS SUGGEST THE
SNOWFALL HAS PLAYED OUT.
UPDATE ISSUED AT 721 PM MDT SUN OCT 12 2014
WINDS HAVE DIMINISHED QUITE A BIT DURING THE PAST 1-2 HOURS.
FORECAST UPDATE TO CANCEL THE WIND ADVISORY FOR THE SOUTHERN
VALLEYS. SNOW SHOWERS WILL BE DIMINISHING AND IF CURRENT TREND
HOLDS...THE WINTER WEATHER ADVISORIES MAY BE CANCELLED EARLY BUT
STILL HAVING SOME IMPACT.
&&
.SHORT TERM...(TONIGHT THROUGH MONDAY NIGHT)
ISSUED AT 246 PM MDT SUN OCT 12 2014
ACTIVE WEATHER DAY CONTINUES WITH SNOW...RAIN...GUSTY WINDS...AND
THUNDERSTORMS ALL PLAYING A PART. THE COLD FRONT RESPONSIBLE FOR
THE PRECIP HAS ALREADY PUSHED OUT OF THE CWA AND DID SO FASTER
THAN ANTICIPATED. IN FACT...IT MOVED OVER DURANGO AROUND NOON
WHICH WAS SEVERAL HOURS QUICKER THAN ORIGINALLY FORECAST. EVEN
SO...THE ASSOCIATED SNOWFALL CAUSED SOME HEADACHES OVER MTN PASSES
ESPECIALLY VAIL PASS THAT WAS CLOSED FOR SOME TIME THIS MORNING
AND AFTERNOON. LOCAL SNOTELS SHOWING UPWARDS OF 6 INCHES HAVING
FALLEN NEAR TOWER AND SPOTTERS REPORTING AN INCH OR TWO AT MTN
BASES THOUGH THAT SNOW QUICKLY MELTED. UNSETTLED W TO NW FLOW HAS
SET UP BEHIND THE FRONT AND WILL KEEP PRECIP IN THE PICTURE
THROUGH THIS AFTN AND EVENING. ONE BIG DIFFERENCE FOR THIS TIME
FRAME IS THE ON AGAIN OFF AGAIN NATURE OF THE PRECIP DUE TO ITS
CONVECTIVE NATURE. WILL KEEP ADVISORIES IN PLACE. OF NOTE IS
LATEST RAP13 AND HRRR SHOWING PRECIP REALLY WINDING DOWN EARLY
THIS EVENING AS OPPOSED TO MIDNIGHT SO CHANCE DOES EXIST FOR SOME
WINTER HIGHLIGHTS TO BE PULLED DOWN EARLY.
PRESSURE GRADIENT REMAINS TIGHT AND REFLECTED IN ALMOST ALL AREAS
REPORTING WIND GUSTS. THESE GUSTS HAVE RANGED FROM 20 MPH TO 45
MPH AT THE DURANGO AIRPORT. THE WIND WILL SLOWLY START DYING DOWN
N OF I-70 A LITTLE AFTER 6PM WHILE AREAS SOUTH WILL BE A LITTLE
LATER. THE WIND ADVISORIES WILL CONTINUE. ALSO UPGRADED THE FREEZE
WATCH TO WARNINGS AS GUIDANCE STILL SHOWING BELOW FREEZING TEMPS
OVERNIGHT WHICH MAKES SENSE AS NORTHERLY FLOW WILL CONTINUE TO
USHER IN COLD AIR WHILE CLOUD COVER WILL DECREASE. A BRISK MORNING
IN STORE.
A LARGE AREA OF HIGH PRESSURE WILL BUILD IN MONDAY BRINGING A
PROLONGED PERIOD OF PRECIP-FREE WEATHER AND A WARMING TREND AS
DESCRIBED BELOW.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 246 PM MDT SUN OCT 12 2014
HIGH PRESSURE WILL CONTINUE TO BUILD OVER THE REGION TUESDAY
BRINGING VERY DRY AND PLEASANT AUTUMN CONDITIONS. THE RIDGE AXIS
MOVES EAST ON WEDNESDAY AS A PACIFIC NORTHWEST TROUGH MOVES
ONSHORE. SOUTHWEST WINDS WILL INCREASE OVER THE NORTHWESTERN PART
OF OUR FORECAST AREA WEDNESDAY MORNING AS THE PRESSURE GRADIENT
BETWEEN THE TROUGH AND RIDGE TIGHTENS. GOOD MODEL CONSENSUS ON THE
RIDGE FLATTENING AND COOLER AIR OVER NORTHERN UTAH AND COLORADO ON
THURSDAY BEFORE RIDGING STRENGTHENS AGAIN ON FRIDAY.
THE LONG RANGE FORECAST MODELS DIVERGE ON SATURDAY BUT BOTH KEEP
CONDITIONS DRY NEXT WEEKEND THROUGHOUT THE REGION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1110 PM MDT SUN OCT 12 2014
SHOWERS CONTINUE TO DIMINISH ACROSS WESTERN COLORADO TONIGHT AND
WILL COME TO AN END AROUND 09Z THIS MORNING. NEAR SHOWERS EXPECT
MVFR TO IFR CIGS AND VSBYS WITH OCCASIONAL MOUNTAIN OBSCURATIONS.
OTHERWISE VFR CONDITIONS ARE EXPECTED ACROSS THE AREA THROUGH
MONDAY EVENING.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...FREEZE WARNING UNTIL 9 AM MDT THIS MORNING FOR COZ001-007-008-
020>022.
UT...NONE.
&&
$$
UPDATE...JDC
SHORT TERM...TGR
LONG TERM...JAM
AVIATION...JDC
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1112 PM MDT SUN OCT 12 2014
.UPDATE...
ISSUED AT 910 PM MDT SUN OCT 12 2014
ROAD REPORTS AND WEB CAMS SUGGEST THAT SNOW OVER VAIL PASS
CONTINUES TO HAVE IMPACT...AND THE SAME HOLDS TRUE FOR MONARCH
PASS. THE SNOW MAY HAVE STOPPED OVER RABBIT EARS BUT RADAR STILL
SHOW SHOWERS NORTH OF HIGHWAY 40 AND MOVING SOUTHWARD. WILL LET
THE WINTER WEATHER ADVISORY PLAY OUT. SNOW HAS DIMINISHED OVER THE
NWRN SAN JUAN MOUNTAINS AND HAVE ALLOWED THE ADVISORY TO EXPIRE. A
FEW FLURRIES STILL ONGOING...BUT REMOTE SENSORS SUGGEST THE
SNOWFALL HAS PLAYED OUT.
UPDATE ISSUED AT 721 PM MDT SUN OCT 12 2014
WINDS HAVE DIMINISHED QUITE A BIT DURING THE PAST 1-2 HOURS.
FORECAST UPDATE TO CANCEL THE WIND ADVISORY FOR THE SOUTHERN
VALLEYS. SNOW SHOWERS WILL BE DIMINISHING AND IF CURRENT TREND
HOLDS...THE WINTER WEATHER ADVISORIES MAY BE CANCELLED EARLY BUT
STILL HAVING SOME IMPACT.
&&
.SHORT TERM...(TONIGHT THROUGH MONDAY NIGHT)
ISSUED AT 246 PM MDT SUN OCT 12 2014
ACTIVE WEATHER DAY CONTINUES WITH SNOW...RAIN...GUSTY WINDS...AND
THUNDERSTORMS ALL PLAYING A PART. THE COLD FRONT RESPONSIBLE FOR
THE PRECIP HAS ALREADY PUSHED OUT OF THE CWA AND DID SO FASTER
THAN ANTICIPATED. IN FACT...IT MOVED OVER DURANGO AROUND NOON
WHICH WAS SEVERAL HOURS QUICKER THAN ORIGINALLY FORECAST. EVEN
SO...THE ASSOCIATED SNOWFALL CAUSED SOME HEADACHES OVER MTN PASSES
ESPECIALLY VAIL PASS THAT WAS CLOSED FOR SOME TIME THIS MORNING
AND AFTERNOON. LOCAL SNOTELS SHOWING UPWARDS OF 6 INCHES HAVING
FALLEN NEAR TOWER AND SPOTTERS REPORTING AN INCH OR TWO AT MTN
BASES THOUGH THAT SNOW QUICKLY MELTED. UNSETTLED W TO NW FLOW HAS
SET UP BEHIND THE FRONT AND WILL KEEP PRECIP IN THE PICTURE
THROUGH THIS AFTN AND EVENING. ONE BIG DIFFERENCE FOR THIS TIME
FRAME IS THE ON AGAIN OFF AGAIN NATURE OF THE PRECIP DUE TO ITS
CONVECTIVE NATURE. WILL KEEP ADVISORIES IN PLACE. OF NOTE IS
LATEST RAP13 AND HRRR SHOWING PRECIP REALLY WINDING DOWN EARLY
THIS EVENING AS OPPOSED TO MIDNIGHT SO CHANCE DOES EXIST FOR SOME
WINTER HIGHLIGHTS TO BE PULLED DOWN EARLY.
PRESSURE GRADIENT REMAINS TIGHT AND REFLECTED IN ALMOST ALL AREAS
REPORTING WIND GUSTS. THESE GUSTS HAVE RANGED FROM 20 MPH TO 45
MPH AT THE DURANGO AIRPORT. THE WIND WILL SLOWLY START DYING DOWN
N OF I-70 A LITTLE AFTER 6PM WHILE AREAS SOUTH WILL BE A LITTLE
LATER. THE WIND ADVISORIES WILL CONTINUE. ALSO UPGRADED THE FREEZE
WATCH TO WARNINGS AS GUIDANCE STILL SHOWING BELOW FREEZING TEMPS
OVERNIGHT WHICH MAKES SENSE AS NORTHERLY FLOW WILL CONTINUE TO
USHER IN COLD AIR WHILE CLOUD COVER WILL DECREASE. A BRISK MORNING
IN STORE.
A LARGE AREA OF HIGH PRESSURE WILL BUILD IN MONDAY BRINGING A
PROLONGED PERIOD OF PRECIP-FREE WEATHER AND A WARMING TREND AS
DESCRIBED BELOW.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 246 PM MDT SUN OCT 12 2014
HIGH PRESSURE WILL CONTINUE TO BUILD OVER THE REGION TUESDAY
BRINGING VERY DRY AND PLEASANT AUTUMN CONDITIONS. THE RIDGE AXIS
MOVES EAST ON WEDNESDAY AS A PACIFIC NORTHWEST TROUGH MOVES
ONSHORE. SOUTHWEST WINDS WILL INCREASE OVER THE NORTHWESTERN PART
OF OUR FORECAST AREA WEDNESDAY MORNING AS THE PRESSURE GRADIENT
BETWEEN THE TROUGH AND RIDGE TIGHTENS. GOOD MODEL CONSENSUS ON THE
RIDGE FLATTENING AND COOLER AIR OVER NORTHERN UTAH AND COLORADO ON
THURSDAY BEFORE RIDGING STRENGTHENS AGAIN ON FRIDAY.
THE LONG RANGE FORECAST MODELS DIVERGE ON SATURDAY BUT BOTH KEEP
CONDITIONS DRY NEXT WEEKEND THROUGHOUT THE REGION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1110 PM MDT SUN OCT 12 2014
SHOWERS CONTINUE TO DIMINISH ACROSS WESTERN COLORADO TONIGHT AND
WILL COME TO AN END AROUND 09Z THIS MORNING. NEAR SHOWERS EXPECT
MVFR TO IFR CIGS AND VSBYS WITH OCCASIONAL MOUNTAIN OBSCURATIONS.
OTHERWISE VFR CONDITIONS ARE EXPECTED ACROSS THE AREA THROUGH
MONDAY EVENING.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR COZ004-
010-012-013.
FREEZE WARNING UNTIL 9 AM MDT MONDAY FOR COZ001-007-008-020>022.
UT...NONE.
&&
$$
UPDATE...PF
SHORT TERM...TGR
LONG TERM...JAM
AVIATION...JDC
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
335 AM EDT MON OCT 13 2014
.SYNOPSIS...
07Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS THAT THE ANTICIPATED BIG
PATTERN AMPLIFICATION IS WELL UNDERWAY. POTENT SHORTWAVE ENERGY HAS
DROPPED SOUTH OVER THE ROCKIES INTO THE SOUTHERN PLAINS AND HAS
CARVED OUT A DEEP AND SHARP TROUGH OVER THE HIGH PLAINS EARLY THIS
MORNING. THIS TROUGH WILL CONTINUE TO AMPLIFY THROUGH THE DAY AS IT
SLOWLY PROGRESSES EASTWARD TOWARD THE MS VALLEY. WIDESPREAD
THUNDERSTORMS...SOME OF WHICH WILL BE SEVERE...WILL PRECEDE THIS
FEATURE ALONG AN ASSOCIATED COLD FRONT SURGING EASTWARD. THIS FRONT
WILL EVENTUALLY ARRIVE OVER THE FLORIDA PENINSULA TUESDAY
NIGHT...ALTHOUGH THE THREAT FOR SEVERE WEATHER APPEARS QUITE LOW FOR
OUR FORECAST AREA AHEAD OF THE FRONT.
DOWNSTREAM THE FLOW RIDGES BACK UP ALONG THE EASTERN SEABOARD AND
WESTERN ATLANTIC. THE FLORIDA PENINSULA IS STILL UNDER THE CONTROL
OF THIS UPPER RIDGE...HOWEVER THE RIDGE AXIS IS BEGINNING TO SHIFT
EAST OF US...AND ALLOW SOME HIGHER LEVEL MOISTURE BACK OVER THE
REGION AS SEEN IN WV IMAGERY. DID SEE A FEW STORMS POP UP DOWN
ACROSS THE SOUTHERN PENINSULA THIS PAST EVENING ALONG A SLOWLY
NORTHWARD RETREATING MOISTURE GRADIENT...REACHING AS FAR NORTH AS
LEE COUNTY. THIS GRADIENT WILL CONTINUE TO SLIDE SLOWLY NORTH ALONG
THE FLORIDA WEST COAST TODAY...HOWEVER THE REAL DEEP LAYER MOISTURE
SURGE STILL LOOKS TO OVERTAKE THE MAJORITY OF THE REGION TONIGHT.
AT THE SURFACE...HIGH PRESSURE CENTERED NEAR SOUTHERN NEW ENGLAND
RIDGES ALL THE WAY DOWN THE ATLANTIC SEABOARD TO OUR REGION. A
DEEPENING CYCLONE LOCATED OVER THE SOUTHERN PLAINS AND ASSOCIATED
WITH THE DIGGING SHORTWAVE WILL SHIFT NORTHEASTWARD TODAY WHILE ITS
TRAILING COLD FRONT MOVES EASTWARD TO THE LOWER MS VALLEY.
&&
.SHORT TERM (TODAY THROUGH TUESDAY)...
TODAY AND TONIGHT...
MONDAY WILL BE THE TRANSITION DAY BETWEEN THE DRY STRETCH OF WEATHER
MOST OF US HAVE EXPERIENCE FOR SEVERAL DAYS NOW...AND THE NEXT
WIDESPREAD RAIN CHANCE ARRIVING TUESDAY AND TUESDAY NIGHT.
THE SHARPNESS AND DEEPNESS OF THE UPPER TROUGH TO OUR WEST WILL
ACTUALLY HELP OUR SITUATION FOR TODAY AS THE RAPID HEIGHT FALLS AND
PV REDISTRIBUTION OVER THE MS VALLEY WILL HELP FORCE AN
AMPLIFICATION / SHORTING OF THE WAVELENGTH TO THE DOWNSTREAM RIDGE
IN CONTROL OF OUR REGION. ESSENTIALLY THIS WILL ALLOW THE RIDGE ONE
MORE FULL DAY TO DOMINATE OUR WEATHER...AND HOLD BACK ANY
SIGNIFICANT DEEP LAYER MOISTURE RETURN UNTIL TONIGHT. GOOD AGREEMENT
BETWEEN THE GFS/NAM IN THE SHARP BACK EDGE OF THE RIDGE KEEPING THE
TIGHT MOISTURE GRADIENT ALONG THE SW FL COAST...AND THEN JUST
OFFSHORE OF THE NATURE COAST UP INTO WESTERN APALACHEE BAY. IT WILL
BE ALONG THIS MOISTURE GRADIENT WHERE THE BEST CHANCES OF
AFTERNOON/EVENING STORMS WILL EXIST. NOW...MOISTURE IS ONLY PART OF
THE EQUATION. WE STILL NEED A TRIGGER FOR THE STORMS. CERTAINLY WE
ARE STILL UNDER THE RIDGE AND WELL REMOVED FROM ANY SYNOPTICS/LARGE
SCALE ASCENT ASSOCIATED WITH THE TROUGH TO OUR WEST...SO WILL NEED
SOMETHING MORE MESOSCALE. THE WINDS ABOVE THE SURFACE ARE SIMPLY TOO
STRONG TO ALLOW FOR A DEFINED SEA-BREEZE TO DEVELOP THIS AFTERNOON.
HOWEVER...WOULD STILL ANTICIPATE A WEAKENING OF THE WINDS ACROSS THE
NEAR SHORE WATERS IN RESPONSE TO THE STRONG TERRESTRIAL HEATING.
THIS WEAKENING OF THE WINDS WILL SET UP A ZONE OF SPEED CONVERGENCE
NEAR THE COAST AS THE STRONGER EAST TO WEST MIXED LAYER WINDS OVER
LAND BUMP UP AGAINST THE ZONE OF WEAKER MARINE WINDS.
VERY GOOD AGREEMENT AMOUNT THE LAST 3-4 RUNS OF THE LOCAL HIRES
CONVECTION ALLOWING MODELS IN THIS LATE DAY CONVECTIVE DEVELOPMENT
ALONG THE IMMEDIATE SUNCOAST...UP AS FAR NORTH AS TAMPA BAY/PINELLAS
COUNTY. THIS IS ALSO VERY SIMILAR TO THE WHERE THE CONVECTIVE
SCHEMES ARE BEING TRIGGERED ON THE NAM AND MANY OF THE SREF ENSEMBLE
MEMBERS. WILL HAVE HIGHEST POPS 40-50% DURING THE LATE AFTERNOON AND
EVENING OVER THIS SPECIFIED AREA MENTIONED ABOVE...AND THEN TAPER
RAIN CHANCES QUICKLY FURTHER TO THE WEST INTO THE SOUTH-CENTRAL
ZONES...AND ALSO NORTHWARD INTO THE NATURE COAST.
TEMPERATURES WORKED OUT WELL ON SUNDAY WITH UPPER 80S TO AROUND 90
AT MOST SPOTS. WILL CONTINUE THE SAME PHILOSOPHY OF TAKING A DEGREE
OR 2 OFF OF A MAV/MET BLEND TO ARRIVE AT A HIGH TEMPERATURE
FORECAST.
THE UPPER RIDGE FINALLY BEGINS TO LOSE INFLUENCE ON OUR REGION
TONIGHT...ALLOWING SLIGHT HEIGHT FALLS BY DAWN. WILL SEE A MORE
NORTHWARD AND EASTWARD PUSH TO THE DEEP LAYER MOISTURE RETURN.
EVENING STORMS ALONG THE COAST WILL MIGRATE OFFSHORE AND THAT WILL
SET UP A MAINLY DRY OVERNIGHT PERIOD FOR OUR LAND ZONES...AS STILL
ANTICIPATE ANY APPRECIABLE SYNOPTIC SUPPORT FOR ASCENT TO REMAIN TO
WELL TO OUR WEST. HIGHER CHANCES FOR CONTINUED OR DEVELOPING
SHOWERS/STORMS WILL EXIST OVER THE GULF WATERS IN CLOSER PROXIMITY
TO THE MAIN SYNOPTICS OF THE TROUGH AND APPROACHING COLD FRONT.
TUESDAY WILL SEE DEEP LAYER MOISTURE FIRMLY IN PLACE OVER THE AREA.
GENERALLY SPEAKING THE MAIN BAND OF SHOWERS/STORMS AHEAD OF THE COLD
FRONT WILL STILL REMAIN TO OUR WEST DURING THE DAYLIGHT HOURS...AS
WILL ANY SUBSTANTIAL HEIGHT FALLS / QG FORCING. HOWEVER...LOW LEVEL
FLOW IS SHOWN TO BECOME SOMEWHAT CONVERGENT OVER THE
PENINSULA...WHILE ALOFT...THE EVOLVING JET STRUCTURE RESULTS IN WEAK
DIFFLUENCE. THEREFORE...THE COMBINATION OF ABUNDANT MOISTURE...
A WEAK LOW LEVEL AND UPPER LEVEL FOCUS MECHANISM...AND SOME ADDED
DIURNAL HEATING...SHOULD COMBINE TO TRIGGER SCT-NMRS SHOWERS AND
STORMS INTO THE AFTERNOON/EVENING HOURS. THESE STORMS ARE NOT LIKELY
TO BE ORGANIZED...BUT CERTAINLY COULD RESULT IN SOME LOCALLY HEAVY
RAINFALL.
&&
.LONG TERM (WEDNESDAY THROUGH NEXT SUNDAY)...
AN UPPER LEVEL LOW OVER THE MID-MISSISSIPPI VALLEY...WITH A SURFACE
REFLECTION TAILING A COLD FRONT THAT ARCS THROUGH THE SOUTHEAST U.S.
AND ACROSS THE GULF TO THE YUCATAN...SLOWLY PUSHES EAST. IT REACHES
THE LOWER GREAT LAKES AND CENTRAL APPALACHIANS THU WITH THE TRAILING
FRONT TRACKING ACROSS CENTRAL FL WED THEN INTO SOUTH FL THU. FRI
THROUGH SUN...THE UPPER LOW LIFTS NORTHWARD ACROSS THE GREAT LAKE
WHILE UPPER LEVEL RIDGING BUILDS OVER THE WESTERN AND SOUTH-CENTRAL
CONUS...THEN SLIDES EAST. SURFACE HIGH PRESSURE SETTLES IN OVER THE
GULF...DOMINATING INTO THE WEEKEND.
THE FORECAST IS A BLEND OF THE LATEST GFS/ECMWF/CMC WHICH ARE ALL
VERY SIMILAR IN THEIR SOLUTIONS. DEEP SOUTH AND SOUTHWEST FLOW WILL
CONTINUE TO STREAM MOISTURE NORTHWARD ACROSS THE GULF...AHEAD OF THE
FRONT...EARLY IN THE PERIOD. SCATTERED TO NUMEROUS SHOWERS AND
STORMS TUE NIGHT PUSH EASTWARD...WITH THE GREATEST COVERAGE MOVING
ACROSS DURING THE DAY AS THE FRONT MOVES INTO WEST CENTRAL FL.
PRECIPITATION TAPERS DOWN WED NIGHT THEN ENDS FROM NORTHWEST TO
SOUTHEAST DURING THU. THE RIDGING TO THE WEST WILL KEEP A DRY AND
SOMEWHAT COOLER AIRMASS IN PLACE FOR THE REST OF THE PERIOD. IN THIS
CASE COOLER MEANS TEMPERATURES DROP DOWN TO AROUND SEASONAL VALUES.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS THE REGION EARLY THIS MORNING AND ARE
EXPECTED TO GENERALLY CONTINUE THROUGH THE TAF PERIOD. THE ONLY
EXCEPTION WOULD BE BRIEF RESTRICTIONS LATE IN THE AFTERNOON OR EARLY
EVENING ASSOCIATED WITH SCT STORMS CLOSE TO THE COAST. MOST LIKELY
TERMINALS TO SEE A STORM WOULD BE FROM KFMY/KRSW TO KSRQ...WITH THE
LEAST CHANCE AT SEEING A STORM AT KLAL.
&&
.MARINE...
HIGH PRESSURE CONTINUES TO RIDGE DOWN THE ATLANTIC SEABOARD TO THE
EASTERN GULF OF MEXICO. THIS RIDGING WILL SLOWLY MIGRATE EASTWARD
DURING THE EARLY PART OF THE WEEK AS A COLD FRONT APPROACHES FROM
THE WEST. AREAS OF CAUTIONARY LEVEL WINDS WILL DIMINISH BELOW 15
KNOTS FOR THE AFTERNOON HOURS AND THEN INCREASE BACK TO CAUTIONARY
LEVELS TONIGHT AND THROUGH MUCH OF THE DAY TUESDAY. THE COLD FRONT
WILL THEN CROSS THE EASTERN GULF OF MEXICO TUESDAY NIGHT AND
WEDNESDAY WITH A WIND SHIFT TO THE NORTHWEST AND NORTH IN ITS WAKE.
HIGH PRESSURE WITH LIGHT WINDS AND LOW SEAS ARE THEN EXPECTED FOR
THE LATER PORTION OF THE WEEK.
&&
.FIRE WEATHER...
HIGH PRESSURE WILL HOLD CONTROL OF THE REGION FOR ONE MORE DAY
BEFORE A COLD FRONT APPROACHES FROM THE WEST ON TUESDAY. AHEAD OF
THE FRONT...A SLOW INCREASE IN LOW LEVEL MOISTURE IS EXPECTED.
RELATIVE HUMIDITY VALUES WILL REMAIN ABOVE CRITICAL LEVELS THROUGH
THE MIDDLE OF THE WEEK...HOWEVER WE WILL SEE HIGH DISPERSION INDICES
THE BOTH THIS AFTERNOON AND AGAIN ON TUESDAY AFTERNOON. THE COLD
FRONT WILL SLOWLY CROSS THE AREA TUESDAY NIGHT AND WEDNESDAY WITH
HIGH PRESSURE AND DRIER CONDITIONS ARRIVING IN ITS WAKE FOR THE END
OF THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 90 75 87 74 / 20 20 60 50
FMY 90 74 89 75 / 40 20 60 30
GIF 90 71 89 72 / 0 0 60 40
SRQ 89 74 87 73 / 40 40 60 50
BKV 91 72 87 71 / 10 10 60 50
SPG 89 77 87 76 / 30 40 60 50
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...MROCZKA
LONG TERM...RUDE
AREA FORECAST DISCUSSION
NWS PADUCAH KY
350 AM CDT Mon Oct 13 2014
.SHORT TERM...(Today through Wednesday)
Issued at 350 AM CDT MON OCT 13 2014
Decided not to issue a Flash Flood Watch at this time. The latest
HRRR has the main line into Carter and Ripley counties around 18Z
and to the Mississippi River by 21Z this afternoon. Looking at
current radar mosaics, it appears that the latest HRRR may even be
a bit slow. Anyway, followed it fairly closely in timing the main
band through the area in the PoP grids. This is a bit faster than
the previous forecast.
The main convective band may hang up a bit tonight over the
Pennyrile and southwest Indiana, and that is where the heaviest
rain is likely to fall. Using the latest HPC QPF gives that region
2.5"-3" through tonight, which is below 3 hour FFG. Certainly
could see some nuisance issues, but nothing widespread or
significant is expected based on the QPF and FFG. If the FFG is
lowered after this morning`s rains are processed, then the day
shift can re-evaluate.
The 00Z models and the latest HRRR indicate that some scattered
convection will be possible over much of the area through midday,
but then it should dry out, as the main convective band begins to
move through the region. Still cannot rule out a strong storm
through midday, if they become surface-based late this morning.
Damaging winds and hail would be the primary concern.
Wind fields will increase significantly later this afternoon,
presumably with the main band. However, as the line is pushed
faster to the east, there is some concern that it may outrun the
strongest wind fields. Either way there will be plenty of 0-3km
helicity to support rotating updrafts and the 0-1km shear will be
quite strong. The bottom line is that damaging winds and some
tornadoes will be possible. If a supercell can get going just
ahead of the line or persist within the line, a more significant
damaging wind and tornado threat can be expected.
As for timing, figure that the main line will enter Ripley and
Carter counties near 18Z, and push east of the area just after
06Z. That would result in a 12 hour window for severe weather and
heavy rainfall.
Will have to keep good chance PoPs going throughout the region
Tuesday through Wednesday due to the proximity of the upper low,
and the presence of a weak surface trough. The best coverage of
showers is expected Wednesday as the upper low moves right
overhead.
.LONG TERM...(Wednesday through Sunday)
Issued at 350 AM CDT MON OCT 13 2014
The GFS continues to slow down the departure of the pesky upper
level low that will be with us for most of the early part of this
week. Yesterdays 00Z GFS run indicated that the low would be exiting
on Wednesday and now, todays 00Z run indicates that it will be more
like Wednesday night. The 00Z ECMWF is now very similar to the 00Z
GFS. Therefore, chances for showers will continue Wednesday
night/Thursday but chances will be greatest in the east/northeast.
After this system pulls out of the area, a weak/dry front moves
through the area on Friday, followed by high pressure that will keep
us dry through Sunday. Another system may bring us a chance for more
precipitation on Sunday night, but confidence is not high yet so
will keep chances low.
After one more day in the 60s on Thursday, we should finally see
readings into the 70s on Friday, but cool off a bit on Saturday and
Sunday behind the weak cold front.
&&
.AVIATION...
Issued at 1148 PM CDT SUN OCT 12 2014
Moist southerly flow ahead of an approaching low pressure system
will keep low VFR or MVFR ceilings around through the greater part
of the forecast period. Isolated showers will be possible just about
anytime, but the greatest chance appears to be with the passage of a
ripple of energy late tonight and early Monday morning. The approach
of a cold front will bring a line of potentially strong to severe
thunderstorms late Monday afternoon and evening. Light south to
southeast winds tonight will become sustained 12 to 15 knots by late
Monday morning. Some gusts as high as 20 to 25 knots are possible
Monday afternoon.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...DRS
LONG TERM...CW
AVIATION...RJP
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1225 AM CDT MON OCT 13 2014
.AVIATION...
FOR THE 13/06Z TAFS...EXPECT A CONTINUED LOWERING OF CIGS TO
IFR/LIFR THIS MORNING AS CONVECTION BEGINS TO INCREASE FROM THE
WEST OUT AHEAD OF A STRONG COLD FRONT OVER WEST TEXAS. AN INTENSE
LINE OF SHWRS/TSTMS WILL BEGIN TO SPREAD EWRD AS WE SHIFT AHEAD
TO MID/LATE MORNING IN ADVANCE OF THE FRONT IN N CNTRL TX/ERN OK.
THESE STORMS WILL RACE RAPIDLY EWRD ACROSS THE REGION AND PRODUCE
STRONG AND POTENTIALLY DAMAGING STRAIGHT-LINE WINDS THROUGH THE
DAY ON MONDAY. TIMING PUTS THE LINE NEAR TYR/GGG/TXK FROM 12Z-15Z
AND 15Z-18Z AT LFK/SHV/ELD...AND MLU AROUND 18Z-21Z. CIGS WILL
IMPROVE SLIGHTLY AT OUR WRN SITES IN E TX AND POSSIBLY SHV/TXK
NEAR THE END OF THE TAF PERIOD BUT SOME WRAP AROUND MOISTURE FROM
THE UPPER LEVEL LOW MAY KEEP CLOUDS FROM EXITING QUITE AS QUICKLY
BEHIND THE FRONT. THE OTHER CONCERN WILL BE THE STRONG WINDS NOT
ASSOCIATED WITH CONVECTION AS S/SW FLOW WILL PICK UP LATER THIS
MORNING AND WIND SPEEDS WILL INCREASE TO 12-20 KTS WITH HIGHER
GUSTS APPROACHING 25-30 KTS. W/NW WINDS EXPECTED BEHIND THE FRONT
WITH SPEEDS DROPPING OFF AFTER 14/00Z. /19/
&&
.PREV DISCUSSION... /ISSUED 1038 PM CDT SUN OCT 12 2014/
DISCUSSION...
VERY BUSY EVENING...AS SCT CONVECTION RAPIDLY DEVELOPED/BECAME SVR
ACROSS PORTIONS OF EXTREME ERN TX/N LA WITHIN THE WARM SECTOR
ALONG/S OF A WARM FRONT. THIS FRONT CONTINUES TO RAPIDLY MIX NNW
THIS EVENING...WITH VERY LOW STRATUS/PATCHY FG STILL HANGING TOUGH
ATTM ACROSS PORTIONS OF EXTREME NE TX/SE OK/SW AR ALONG/N OF THE
I-30 CORRIDOR. THE INITIAL SHORTWAVE THAT TRIGGERED THE SCT SVR
CONVECTION EARLIER THIS EVENING HAS EJECTED NE OF THE AREA...WITH
ALL EYES FOCUSED TO OUR W WITH THE LONGWAVE TROUGH DIVING SE INTO
THE PLAINS. MOSAIC RADARS ALREADY INDICATING A DEVELOPING SQUALL
LINE OVER CNTRL OK/NW TX...ALONG A STRONG COLD FRONT THAT HAS
MOVED THROUGH THE TX PANHANDLE INTO WRN OK. THE PRESSURE GRADIENT
HAS TIGHTENED OVER THE SRN PLAINS THIS EVENING...WITH STRONG
FRONTAL CONVERGENCE CONTRIBUTING TO SVR CONVECTION...WHERE STRONG
DIFFLUENCE IN THE RRQ OF THE UPPER JET HAS SET UP.
SFC WINDS OVER OUR REGION HAS NOT INCREASED MUCH AS EARLIER
ANTICIPATED...WITH THE GFS MUCH TOO FAST WITH INCREASING WINDS
AHEAD OF AN INTENSIFYING SFC LOW THAT WILL SPREAD SE INTO CNTRL
OK LATE. HAVE DELAYED THE LAKE WIND ADVISORY UNTIL 4AM
MONDAY...AND HAVE MAINTAINED IT THROUGH THE ORIGINAL 7PM EXPIRATION
TIME. HAVE ALSO LOWERED POPS A TAD ACROSS EXTREME E TX/NW
LA/SCNTRL AR AND REMOVED HEAVY RAINFALL WORDING...WITH THE NEW 00Z
NAM IN GOOD AGREEMENT WITH THE HRRR WITH PRE-FRONTAL CONVECTION
DEVELOPING AHEAD OF THE SQUALL LINE MOVING INTO EXTREME SE OK/NE
TX AFTER 08Z. HAVE ALSO ADDED SVR WORDING TO E TX/SE OK AS WELL
LATE...AND ADDED IT AREAWIDE MONDAY AS THE SQUALL LINE RACES
ACROSS THE REGION. WITH THE HRRR AND 00Z NAM SUGGESTING A FASTER
PROGRESSION OF THE SQUALL LINE...HOPEFULLY THIS AND THE MORNING
LOW STRATUS WILL DETER DESTABILIZATION SOME OVER NCNTRL LA/SCNTRL
AR. HOWEVER...A SLOWER EWD PROGRESSION WOULD SUGGEST MORE
HEATING/INSTABILITY WITHIN A STRONGLY SHEARED ENVIRONMENT...WHICH
WOULD RESULT IN AN ENHANCED SVR THREAT.
AM CONCERNED FOR POTENTIAL FLOODING ISSUES LATE TONIGHT/MONDAY
MORNING ESPECIALLY OVER SE OK/ADJACENT SECTIONS OF SW AR /OUR NRN
COUNTIES/...AS ANY PRE-SQUALL LINE CONVECTION WOULD TEND TO TRAIN
OVER THESE AREAS...RESULTING IN 2-4+ INCH QPF/S OVER ALREADY
SATURATED GROUNDS. WILL NOT ISSUE A FLASH FLOOD WATCH FOR THESE
AREAS JUST YET...AS THE SQUALL LINE MAY QUICKLY OVERTAKE THE PRE-
FRONTAL CONVECTION AND LIMIT TRAINING. HOWEVER...LOCALIZED FLASH
FLOODING WILL REMAIN POSSIBLE.
DID ADJUST MIN TEMPS SLIGHTLY TONIGHT...WITH CURRENT TEMPS SEVERAL
DEGREES BELOW THE ORIGINAL FORECAST VALUES. HOWEVER...TEMPS SHOULD
SLOWLY WARM OVERNIGHT AS WINDS/LOW STRATUS INCREASES ACROSS THE
NWN EXPANDING WARM SECTOR.
ZONE UPDATE/NPW ALREADY OUT...GRIDS WILL BE AVAILABLE SHORTLY.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 67 79 53 74 48 / 50 100 10 10 10
MLU 68 82 55 73 50 / 40 100 40 10 10
DEQ 64 75 52 71 42 / 80 100 30 10 10
TXK 65 77 52 71 48 / 60 100 20 10 10
ELD 67 78 52 70 46 / 50 100 30 10 10
TYR 68 74 51 75 49 / 70 100 10 10 10
GGG 66 77 52 76 46 / 50 100 10 10 10
LFK 70 82 52 78 48 / 30 100 10 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...LAKE WIND ADVISORY FROM 4 AM TO 7 PM CDT MONDAY FOR THE
FOLLOWING ZONES: ARZ050-051-059>061-070>073.
LA...LAKE WIND ADVISORY FROM 4 AM TO 7 PM CDT MONDAY FOR THE
FOLLOWING ZONES: LAZ001>006-010>014-017>022.
OK...LAKE WIND ADVISORY FROM 4 AM TO 7 PM CDT MONDAY FOR THE
FOLLOWING ZONES: OKZ077.
TX...LAKE WIND ADVISORY FROM 4 AM TO 7 PM CDT MONDAY FOR THE
FOLLOWING ZONES:
TXZ096-097-108>112-124>126-136>138-149>153-165>167.
&&
$$
19
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
405 AM EDT MON OCT 13 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 404 AM EDT MON OCT 13 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEPENING UPR TROF
OVER THE CENTRAL CONUS AS POTENT SHRTWV DIGS INTO THE SRN PLAINS.
WITHIN THIS LARGER TROF...THERE IS A WEAKER SHRTWV LIFTING NEWD THRU
THE NRN PLAINS...AND SOME ISOLD-SCT SHOWERS IN THE LARGER SCALE
ISENTROPIC ASCENT/SW FLOW/AREA OF H85-5 QVECTOR CNVGC BTWN THAT
SHRTWV AND DEPARTING HI PRES OVER NEW ENGLAND HAVE MOVED INTO THE
UPR LKS DESPITE VERY DRY H7-9 LYR SHOWN ON THE 00Z GRB RAOB. THERE
IS ANOTHER AREA OF SHOWERS OVER MN UNDER THE SHARPER DEEP LYR
QVECTOR CNVGC CLOSER TO THE SHRTWV LIFTING NEWD IN THE NRN
PLAINS...BUT THERE IS LTL IN THE WAY OF PCPN BTWN THE ACTIVITY IN
MN/THE UPR LKS AND MORE WDSPRD SHRA/TS IN THE SCENTRAL PLAINS
ASSOCIATED WITH DEEPER SHRTWV IN THAT AREA DESPITE PWATS AS HI AS AN
INCH /UP TO 150 PCT OF NORMAL/ AT QUAD CITIES IOWA.
MAIN FCST CONCERNS THRU TNGT ARE FOCUSED ON POPS. STILL LOOKS LIKE
THE MOST WDSPRD...HEAVY RA WL IMPACT THE E HALF OF UPR MI TNGT
CLOSER TO RIBBON OF HIER PWAT/DVLPG FGEN. PER NCEP GUIDANCE...
FOLLOWED THE 00Z NAM/12Z ECMWF MOST CLOSELY FOR FCST DETAILS.
TODAY...AREA OF DEEPER MSTR/SOMEWHAT SHARPER ISENTROPIC ASCENT/AXIS
OF H85-5 QVECTOR CNVGC IS FCST TO MOVE NEWD AND PASS OUT OF UPR MI
BY NOON AND GIVE WAY TO SOME WEAK DEEP LYR QVECTOR DVGC/DRYING ABV
H7...SO EXPECT THE ISOLD-SCT SHOWERS IMPACTING UPR MI TO DIMINISH IN
THE AFTN. MEANWHILE...AS SHRTWV IN THE NRN PLAINS/ACCOMPANYING
QVECTOR CNVGC CONTINUES TO THE NE AND INTO NW ONTARIO...AREA OF
SHOWERS IN MN WL FOLLOW AND TEND TO MISS ALL BUT WRN LK SUP. BUT
WITH PERSISTENT SLY FLOW OF MOISTER AIR TO THE S...EXPECT OVERCAST
SKIES DESPITE THE DIMINISHING PCPN TREND. LATE IN THE DAY TOWARD 00Z
TUE...COMBINATION OF INCRSG UPR DVGC IN RRQ OF 100KT H3 JET MAX
SHIFTING INTO NW ONTARIO WITH NRN SHRTWV...AREA OF DEEP LYR QVECTOR
CNVGC APRCHG FM THE S AND ARRIVAL OF AXIS OF H85-7 FGEN IN COMMA
TAIL OF DEPARTING SHRTWV IN ONTARIO WL BRING A RETURN OF HIER POPS
TO AREAS NEAR THE WI BORDER/SCENTRAL.
TNGT...DEEP SSW FLOW E OF UPR TROF AXIS IS PROGGED TO LIFT PWAT TO
NEAR 1.5 INCHES OVER THE FAR SE CWA NEAR LK MI...NEARLY 250 PCT OF
NORMAL. IN CONCERT WITH UPR DVGC IN RRQ OF INTENSIFYING H3 JET MAX
IN NW ONTARIO AND AXIS OF SHARP H85-7 FGEN/ISENTROPIC ASCENT ON THE
300-305K SFCS /ABOUT H8-7/ NEAR FRONTAL ZN THAT IS FCST TO IMPACT
THE SE PORTION OF THE FA...EXPECT CATEGORICAL POPS/SOME MDT TO AT
TIMES HEAVY RA IN THIS AREA. THE WRN EXTENT OF THE HIER POPS/
HEAVIER RA IS SOMEWHAT IN QUESTION BECAUSE THE MAIN CUTOFF LO
ASSOCIATED WITH THE MORE VIGOROUS SRN BRANCH SHRTWV AND ACCOMPANYING
SHARPER DEEP LYR QVECTOR CNVGC ARE PROGGED TO STAY S OF THE UPR
LKS...WITH UPR DVGC THE MAIN FORCING MECHANISM FOR PCPN TO THE W.
THE 00Z NAM/12Z ECMWF SHOW SUFFICIENT DRYING OVER THE W IN THE WAKE
OF THE SHRTWV MOVING INTO ONTARIO AND SO FAR W OF THE FRONTAL ZN TO
SUPPORT LTL IF ANY PCPN OVER THE FAR W...SO TENDED TO LOWER POPS IN
THIS AREA. OTRW...ADDED SOME FOG OVER THE NCENTRAL WITH UPSLOPE NE
FLOW AND ACRS THE E WHERE THE PWAT IS FCST SO HI.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 357 AM EDT MON OCT 13 2014
TUE WILL SEE DECREASING RAIN CHANCES AS AN FGEN BAND ALONG AN
INVERTED SFC TROUGH MOVES E OF THE CWA. MODELS VARY ON EXACTLY WHERE
THE BAND WILL BE AT IN THE MORNING AND HOW FAST IT WILL MOVE E...BUT
AT LEAST FAR NWRN UPPER MI /FROM IWD THROUGH THE KEWEENAW/ WILL BE
DRY ALL DAY PER THE FARTHER W 00Z/13 GFS SOLUTION. THE 12Z/12 ECMWF
ONLY HAS 0.02 INCHES OF RAIN IN THE MORNING AT ERY. THE 00Z/13 NAM
TAKES THE MIDDLE GROUND...WHICH MAKES IT PREFERABLE GIVEN A LACK OF
PREFERENCE FOR THE GFS VS THE ECMWF. ALL THREE OF THESE MODELS HAVE
THE CWA DRY FROM 18Z THROUGH THE REST OF TUE.
AN ADDITIONAL CONCERN...ESPECIALLY DURING THE TUESDAY INTO TUESDAY
NIGHT TIME PERIOD IS THE POSSIBILITY FOR LARGE WAVES TO DEVELOP ON
THE TIGHTER PRESSURE GRADIENT ALONG THE INVERTED TROUGH. THESE WAVES
WOULD DEVELOP ON GUSTY NORTH TO NORTHEASTERLY WINDS....ALLOWING
WAVES TO REACH AROUND 8 FEET. THIS COULD CAUSE MINOR BEACH EROSION
ALONG THE MARQUETTE AND ALGER COUNTY SHORELINES.
THE ECMWF AND NAM KEEP THE CWA DRY FOR THE MOST PART TUE NIGHT
THROUGH WED WHILE THE GFS BRINGS LIGHT QPF AMOUNTS BACK INTO THE FAR
SERN CWA THROUGH THAT PERIOD. THE REASON FOR THE DISCREPANCY IS THAT
THE GFS SHIFTS THE UPPER LOW FROM CENTRAL IL TO SRN MI WHILE THE
OTHER MODELS KEEP IT OVER IL. BECAUSE OF THIS...THE ECMWF/NAM KEEP
THE UPPER RIDGE EXTENDING N OF THE UPPER LOW ACROSS THE CWA...WHICH
KEEPS THE AIRMASS MUCH DRIER AND FORCING FARTHER S. OPTED TO LOWER
POPS SOME DURING THE PERIOD TO ACCOUNT FOR THE DRIER TREND IN
GUIDANCE. AS HEIGHTS RISE DUE TO THE UPPER RIDGE MOVING N OF THE LOW
AND THE LOW ITSELF FILLING...THE AIRMASS WARMS PRETTY CONSIDERABLY.
850MB TEMPS AT 12Z TUE LOOK TO RANGE FROM 4C W TO 8C E...BUT
INCREASE TO AROUND 11 C OVER THE ENTIRE AREA BY 00Z THU.
DETAILS ARE MUCH LESS CERTAIN AFTER WED...BUT OVERALL THE MODELS
SHOW THE UPPER LOW LIFTING QUICKLY N AND MERGING WITH AN INCOMING
TROUGH THAT DEEPENS INTO A CLOSED LOW /OR AT LEAST A DEEP TROUGH/ AS
IT MOVES THROUGH THE REGION FRI AND SAT. CANNOT GET TOO SPECIFIC AT
THIS POINT GIVEN LACK OF CONFIDENCE...BUT CHANCES FOR PRECIP WILL BE
HIGHER WED NIGHT INTO SAT. A COLD FRONT MOVING THROUGH THU NIGHT OR
FRI WILL BRING COOLER CONDITIONS FRI THROUGH THE WEEKEND. MODELS
HAVE THEN BEEN TRENDING DRIER FOR SUN...SO WILL REFLECT THAT IN THE
FORECAST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 121 AM EDT MON OCT 13 2014
SOME ISOLATED SHOWERS CONTINUE ACROSS UPPER MICHIGAN...HOWEVER THEY
ARE VERY LIGHT AS THE LOW LEVELS REMAIN DRY. AN AREA OF MVFR OR EVEN
IFR CONDITIONS ACROSS IOWA AND SRN WI ARE EXPECTED TO MOVE INTO
UPPER MICHIGAN LATE TONIGHT INTO MON MORNING. MOST LIKELY...THE CIGS
WILL STAY MVFR AS OPPOSED TO IFR DURING THE DAY ON MONDAY. A FRONTAL
BOUNDARY WILL APPROACH FROM THE WEST DURING THE DAY ON MONDAY...AND
LOW PRESSURE WILL DEVELOP ALONG THE FRONT OVER THE SOUTHERN PLAINS.
THIS LOW WILL MOVE TOWARD THE GREAT LAKES MON/MON NIGHT. DEEPER
MOISTURE WILL SPREAD ACROSS THE AREA LATE MONDAY INTO MONDAY
NIGHT...ALONG WITH RAIN. IFR CONDITIONS SHOULD PREVAIL MONDAY NIGHT
ACROSS THE ENTIRE AREA...AND IT WOULD NOT BE SURPRISING IF SOME LIFR
CONDITIONS DEVELOP MONDAY NIGHT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 357 AM EDT MON OCT 13 2014
A WEAKENING PRESSURE GRADIENT ACROSS THE AREA WILL LEAD TO WINDS
WILL DROPPING BELOW 10KT ACROSS THE LAKE BY THIS AFTERNOON. AS A LOW
PRESSURE SYSTEM SLOWLY LIFTS NE...WINDS WILL BECOME N TO NE TONIGHT
AND WILL INCREASE LATE. TUE AND TUE NIGHT...EXPECT N TO NE WINDS UP
TO 20KT ON WRN LAKE SUPERIOR AND UP TO 25KT ON ERN LAKE SUPERIOR.
THE LOW WILL THEN WEAKEN AS IT DRIFTS NE ACROSS THE GREAT LAKES
REGION WED/THU...ALLOWING WINDS TO DIMINISH. WINDS SHOULD BE UNDER
10KT BY THU. ANOTHER LOW PRESSURE SYSTEM TRACKING ACROSS SRN CANADA
THU WILL THEN MERGE WITH THE REMNANT GREAT LAKES LOW ON FRI IN THE
VICINITY OF JAMES BAY. THIS WILL RESULT IN INCREASING W TO NW INTO
THE 15-25KT RANGE ON FRI.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...MRD
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
358 AM EDT MON OCT 13 2014
.UPDATE...
ISSUED AT 904 PM EDT SUN OCT 12 2014
SHOWERS AND/OR SPRINKLES HAVE MOVED INTO WESTERN UPPER MICHIGAN IN
ADVANCE OF THE WEAK UPPER DISTURBANCE ALOFT. WITH THE DWPTS STILL IN
THE LOWER 30S...DO NOT EXPECT MUCH MORE THAN A FEW
SPRINKLES/SHOWERS. HOWEVER...HAVE INTRODUCED ISOLATED SHOWERS MOVING
ACROSS THE AREA OVERNIGHT. IN FACT...HAVE BROUGHT IN SCATTERED POPS
LATER TONIGHT AS THE HRRR INDICATES MORE SHOWER ACTIVITY DEVELOPING
AS THE DISTURBANCE CURRENTLY OVER MISSOURI MOVES OVERHEAD.
OTHERWISE...DUE TO THE EXTENSIVE CLOUD COVER AND CONTINUED GUSTY
WINDS...HAVE RAISED LOW TEMPS SLIGHTLY ACROSS THE REGION TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 414 PM EDT SUN OCT 12 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A DEEPENING TROF MOVING
OFF THE ROCKIES INTO THE WRN PLAINS. DOWNSTREAM OF THE TROF...
INCREASING SOUTHERLY FLOW IS TRANSPORTING MOISTURE N UP THE
MISSISSIPPI RIVER VALLEY. THIS SHOWS UP NICELY ON VIS SATELLITE
IMAGERY AS A MASS OF CLOUDS QUICKLY SPREADING STEADILY N AT ABOUT
30KT WITH LEADING EDGE NOW INTO SE MN AND SW WI AS OF 19Z. CLOSER TO
HOME...IT`S BEEN A NICE MID OCT DAY THOUGH BREEZY IN SOME AREAS.
ADDED MOISTURE OFF LAKE MI LED TO SCT/BKN CLOUDS FOR A WHILE OVER
THE E. OTHERWISE...THERE`S BEEN ABUNDANT SUNSHINE. TEMPS HAVE RISEN
INTO THE MID 50S TO LWR 60S.
WITH A WEAK TEMP GRADIENT OVER THE WRN LAKES TONIGHT...ISENTROPIC
ASCENT IS LIMITED DESPITE CONTINUED SW FLOW. SOME WEAK DEEP LAYER
FORCING IS NOTED AS A COUPLE OF SUBTLE SHORTWAVES LIFT THRU THE WRN
GREAT LAKES. ALL IN ALL...THERE IS NOT A LOT OF SUPPORT FOR MUCH
PCPN EVEN THOUGH MOISTURE INCREASES SUBSTANTIALLY (PRECIPITABLE
WATER INCREASES FROM 50-60PCT OF NORMAL CURRENTLY TO 140-170PCT OF
NORMAL BY 12Z). UPSTREAM RADAR IMAGERY ONLY SHOWS ISOLD TO SCT
-SHRA/SPRINKLES ADVANCING NNE IN THE MOISTURE PLUME...SO A SPREAD OF
SCHC TO SPOTTY LOW CHC POPS N AND E INTO THE FCST AREA APPEARS
REASONABLE TONIGHT. INCREASING MOISTURE/CLOUDS WILL KEEP TEMPS FROM
FALLING SIGNIFICANTLY TONIGHT. 40S WILL BE THE RULE.
ON MON...SUBTLE SHORTWAVE LIFTING NE ACROSS THE AREA EARLY WILL
PROBABLY SUPPORT A CONTINUED THREAT OF ISOLD -SHRA/SPRINKLES IN THE
MORNING...THEN MUCH IF NOT ALL OF THE REST OF THE DAY WILL PROBABLY
END UP DRY UNTIL LATE IN THE AFTN. DURING THE AFTN...STRENGTHENING
OF A JET STREAK FROM MN TO JAMES BAY WILL PLACE UPPER GREAT LAKES
UNDER THE INCREASINGLY FAVORABLE RIGHT ENTRANCE...AND DOWN
BELOW...IT WILL SERVE TO STRENGTHEN LOW/MID LEVEL
FRONTOGENESIS/TIGHTENING OF THE THERMAL GRADIENT ACROSS THE AREA.
ALL MODELS SHOW A HEALTHY RIBBON OF FRONTOGENESIS BEGINNING TO
DEVELOP OVER THE UPPER MISSISSIPPI VALLEY INTO THE UPPER LAKES LATE
IN THE DAY...BUT MUCH MORE SO MON NIGHT. AS A RESULT...A DEVELOPING
AREA OF MDT TO POSSIBLY HVY RAIN SHOULD BEGIN ORGANIZING/SPREADING
NNE THRU THE MID MISSISSIPPPI VALLEY MON AFTN. LEADING EDGE OF THIS
AREA OF DEVELOPING PCPN MAY BEGIN TO REACH THE WRN AND SRN FCST AREA
VERY LATE IN THE DAY...BUT GIVEN SLOWER MODEL TRENDS IN RECENT
DAYS...WOULDN`T BE SURPRISED IF PCPN HOLDS OFF UNTIL AFTER 00Z.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 357 AM EDT MON OCT 13 2014
TUE WILL SEE DECREASING RAIN CHANCES AS AN FGEN BAND ALONG AN
INVERTED SFC TROUGH MOVES E OF THE CWA. MODELS VARY ON EXACTLY WHERE
THE BAND WILL BE AT IN THE MORNING AND HOW FAST IT WILL MOVE E...BUT
AT LEAST FAR NWRN UPPER MI /FROM IWD THROUGH THE KEWEENAW/ WILL BE
DRY ALL DAY PER THE FARTHER W 00Z/13 GFS SOLUTION. THE 12Z/12 ECMWF
ONLY HAS 0.02 INCHES OF RAIN IN THE MORNING AT ERY. THE 00Z/13 NAM
TAKES THE MIDDLE GROUND...WHICH MAKES IT PREFERABLE GIVEN A LACK OF
PREFERENCE FOR THE GFS VS THE ECMWF. ALL THREE OF THESE MODELS HAVE
THE CWA DRY FROM 18Z THROUGH THE REST OF TUE.
AN ADDITIONAL CONCERN...ESPECIALLY DURING THE TUESDAY INTO TUESDAY
NIGHT TIME PERIOD IS THE POSSIBILITY FOR LARGE WAVES TO DEVELOP ON
THE TIGHTER PRESSURE GRADIENT ALONG THE INVERTED TROUGH. THESE WAVES
WOULD DEVELOP ON GUSTY NORTH TO NORTHEASTERLY WINDS....ALLOWING
WAVES TO REACH AROUND 8 FEET. THIS COULD CAUSE MINOR BEACH EROSION
ALONG THE MARQUETTE AND ALGER COUNTY SHORELINES.
THE ECMWF AND NAM KEEP THE CWA DRY FOR THE MOST PART TUE NIGHT
THROUGH WED WHILE THE GFS BRINGS LIGHT QPF AMOUNTS BACK INTO THE FAR
SERN CWA THROUGH THAT PERIOD. THE REASON FOR THE DISCREPANCY IS THAT
THE GFS SHIFTS THE UPPER LOW FROM CENTRAL IL TO SRN MI WHILE THE
OTHER MODELS KEEP IT OVER IL. BECAUSE OF THIS...THE ECMWF/NAM KEEP
THE UPPER RIDGE EXTENDING N OF THE UPPER LOW ACROSS THE CWA...WHICH
KEEPS THE AIRMASS MUCH DRIER AND FORCING FARTHER S. OPTED TO LOWER
POPS SOME DURING THE PERIOD TO ACCOUNT FOR THE DRIER TREND IN
GUIDANCE. AS HEIGHTS RISE DUE TO THE UPPER RIDGE MOVING N OF THE LOW
AND THE LOW ITSELF FILLING...THE AIRMASS WARMS PRETTY CONSIDERABLY.
850MB TEMPS AT 12Z TUE LOOK TO RANGE FROM 4C W TO 8C E...BUT
INCREASE TO AROUND 11 C OVER THE ENTIRE AREA BY 00Z THU.
DETAILS ARE MUCH LESS CERTAIN AFTER WED...BUT OVERALL THE MODELS
SHOW THE UPPER LOW LIFTING QUICKLY N AND MERGING WITH AN INCOMING
TROUGH THAT DEEPENS INTO A CLOSED LOW /OR AT LEAST A DEEP TROUGH/ AS
IT MOVES THROUGH THE REGION FRI AND SAT. CANNOT GET TOO SPECIFIC AT
THIS POINT GIVEN LACK OF CONFIDENCE...BUT CHANCES FOR PRECIP WILL BE
HIGHER WED NIGHT INTO SAT. A COLD FRONT MOVING THROUGH THU NIGHT OR
FRI WILL BRING COOLER CONDITIONS FRI THROUGH THE WEEKEND. MODELS
HAVE THEN BEEN TRENDING DRIER FOR SUN...SO WILL REFLECT THAT IN THE
FORECAST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 121 AM EDT MON OCT 13 2014
SOME ISOLATED SHOWERS CONTINUE ACROSS UPPER MICHIGAN...HOWEVER THEY
ARE VERY LIGHT AS THE LOW LEVELS REMAIN DRY. AN AREA OF MVFR OR EVEN
IFR CONDITIONS ACROSS IOWA AND SRN WI ARE EXPECTED TO MOVE INTO
UPPER MICHIGAN LATE TONIGHT INTO MON MORNING. MOST LIKELY...THE CIGS
WILL STAY MVFR AS OPPOSED TO IFR DURING THE DAY ON MONDAY. A FRONTAL
BOUNDARY WILL APPROACH FROM THE WEST DURING THE DAY ON MONDAY...AND
LOW PRESSURE WILL DEVELOP ALONG THE FRONT OVER THE SOUTHERN PLAINS.
THIS LOW WILL MOVE TOWARD THE GREAT LAKES MON/MON NIGHT. DEEPER
MOISTURE WILL SPREAD ACROSS THE AREA LATE MONDAY INTO MONDAY
NIGHT...ALONG WITH RAIN. IFR CONDITIONS SHOULD PREVAIL MONDAY NIGHT
ACROSS THE ENTIRE AREA...AND IT WOULD NOT BE SURPRISING IF SOME LIFR
CONDITIONS DEVELOP MONDAY NIGHT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 357 AM EDT MON OCT 13 2014
A WEAKENING PRESSURE GRADIENT ACROSS THE AREA WILL LEAD TO WINDS
WILL DROPPING BELOW 10KT ACROSS THE LAKE BY THIS AFTERNOON. AS A LOW
PRESSURE SYSTEM SLOWLY LIFTS NE...WINDS WILL BECOME N TO NE TONIGHT
AND WILL INCREASE LATE. TUE AND TUE NIGHT...EXPECT N TO NE WINDS UP
TO 20KT ON WRN LAKE SUPERIOR AND UP TO 25KT ON ERN LAKE SUPERIOR.
THE LOW WILL THEN WEAKEN AS IT DRIFTS NE ACROSS THE GREAT LAKES
REGION WED/THU...ALLOWING WINDS TO DIMINISH. WINDS SHOULD BE UNDER
10KT BY THU. ANOTHER LOW PRESSURE SYSTEM TRACKING ACROSS SRN CANADA
THU WILL THEN MERGE WITH THE REMNANT GREAT LAKES LOW ON FRI IN THE
VICINITY OF JAMES BAY. THIS WILL RESULT IN INCREASING W TO NW INTO
THE 15-25KT RANGE ON FRI.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...MRD
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...MRD
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
122 AM EDT MON OCT 13 2014
.UPDATE...
ISSUED AT 904 PM EDT SUN OCT 12 2014
SHOWERS AND/OR SPRINKLES HAVE MOVED INTO WESTERN UPPER MICHIGAN IN
ADVANCE OF THE WEAK UPPER DISTURBANCE ALOFT. WITH THE DWPTS STILL IN
THE LOWER 30S...DO NOT EXPECT MUCH MORE THAN A FEW
SPRINKLES/SHOWERS. HOWEVER...HAVE INTRODUCED ISOLATED SHOWERS MOVING
ACROSS THE AREA OVERNIGHT. IN FACT...HAVE BROUGHT IN SCATTERED POPS
LATER TONIGHT AS THE HRRR INDICATES MORE SHOWER ACTIVITY DEVELOPING
AS THE DISTURBANCE CURRENTLY OVER MISSOURI MOVES OVERHEAD.
OTHERWISE...DUE TO THE EXTENSIVE CLOUD COVER AND CONTINUED GUSTY
WINDS...HAVE RAISED LOW TEMPS SLIGHTLY ACROSS THE REGION TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 414 PM EDT SUN OCT 12 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A DEEPENING TROF MOVING
OFF THE ROCKIES INTO THE WRN PLAINS. DOWNSTREAM OF THE TROF...
INCREASING SOUTHERLY FLOW IS TRANSPORTING MOISTURE N UP THE
MISSISSIPPI RIVER VALLEY. THIS SHOWS UP NICELY ON VIS SATELLITE
IMAGERY AS A MASS OF CLOUDS QUICKLY SPREADING STEADILY N AT ABOUT
30KT WITH LEADING EDGE NOW INTO SE MN AND SW WI AS OF 19Z. CLOSER TO
HOME...IT`S BEEN A NICE MID OCT DAY THOUGH BREEZY IN SOME AREAS.
ADDED MOISTURE OFF LAKE MI LED TO SCT/BKN CLOUDS FOR A WHILE OVER
THE E. OTHERWISE...THERE`S BEEN ABUNDANT SUNSHINE. TEMPS HAVE RISEN
INTO THE MID 50S TO LWR 60S.
WITH A WEAK TEMP GRADIENT OVER THE WRN LAKES TONIGHT...ISENTROPIC
ASCENT IS LIMITED DESPITE CONTINUED SW FLOW. SOME WEAK DEEP LAYER
FORCING IS NOTED AS A COUPLE OF SUBTLE SHORTWAVES LIFT THRU THE WRN
GREAT LAKES. ALL IN ALL...THERE IS NOT A LOT OF SUPPORT FOR MUCH
PCPN EVEN THOUGH MOISTURE INCREASES SUBSTANTIALLY (PRECIPITABLE
WATER INCREASES FROM 50-60PCT OF NORMAL CURRENTLY TO 140-170PCT OF
NORMAL BY 12Z). UPSTREAM RADAR IMAGERY ONLY SHOWS ISOLD TO SCT
-SHRA/SPRINKLES ADVANCING NNE IN THE MOISTURE PLUME...SO A SPREAD OF
SCHC TO SPOTTY LOW CHC POPS N AND E INTO THE FCST AREA APPEARS
REASONABLE TONIGHT. INCREASING MOISTURE/CLOUDS WILL KEEP TEMPS FROM
FALLING SIGNIFICANTLY TONIGHT. 40S WILL BE THE RULE.
ON MON...SUBTLE SHORTWAVE LIFTING NE ACROSS THE AREA EARLY WILL
PROBABLY SUPPORT A CONTINUED THREAT OF ISOLD -SHRA/SPRINKLES IN THE
MORNING...THEN MUCH IF NOT ALL OF THE REST OF THE DAY WILL PROBABLY
END UP DRY UNTIL LATE IN THE AFTN. DURING THE AFTN...STRENGTHENING
OF A JET STREAK FROM MN TO JAMES BAY WILL PLACE UPPER GREAT LAKES
UNDER THE INCREASINGLY FAVORABLE RIGHT ENTRANCE...AND DOWN
BELOW...IT WILL SERVE TO STRENGTHEN LOW/MID LEVEL
FRONTOGENESIS/TIGHTENING OF THE THERMAL GRADIENT ACROSS THE AREA.
ALL MODELS SHOW A HEALTHY RIBBON OF FRONTOGENESIS BEGINNING TO
DEVELOP OVER THE UPPER MISSISSIPPI VALLEY INTO THE UPPER LAKES LATE
IN THE DAY...BUT MUCH MORE SO MON NIGHT. AS A RESULT...A DEVELOPING
AREA OF MDT TO POSSIBLY HVY RAIN SHOULD BEGIN ORGANIZING/SPREADING
NNE THRU THE MID MISSISSIPPPI VALLEY MON AFTN. LEADING EDGE OF THIS
AREA OF DEVELOPING PCPN MAY BEGIN TO REACH THE WRN AND SRN FCST AREA
VERY LATE IN THE DAY...BUT GIVEN SLOWER MODEL TRENDS IN RECENT
DAYS...WOULDN`T BE SURPRISED IF PCPN HOLDS OFF UNTIL AFTER 00Z.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 414 PM EDT SUN OCT 12 2014
TEMPERATURES WILL REMAIN NEAR NORMAL THROUGH THE EXTENDED FORECAST
WITH WET WEATHER EXPECTED THROUGHOUT THIS FORECAST PERIOD. THE
HEAVIEST RAIN IS EXPECTED MONDAY NIGHT INTO TUESDAY.
MONDAY NIGHT THROUGH WEDNESDAY...THE SURFACE LOW OVER THE MISSOURI
VALLEY WILL CONTINUE TO STRENGTHEN AS AN UPPER LEVEL LOW CLOSES OFF
JUST TO THE WEST OF THE SURFACE LOW MONDAY NIGHT. FAIRLY STRONG
ISENTROPIC UPGLIDE WILL SET UP EAST AND NORTHEAST OF THE LOW AS
PLENTY OF MOISTURE REMAINS IN PLACE. THIS WILL ALLOW RAIN TO SPREAD
INTO MUCH OF THE AREA MONDAY EVENING AND LINGER THROUGH THE
OVERNIGHT HOURS...WITH THE BETTER FOCUS BEING OVER THE CENTRAL AND
EAST WHERE THE STRONGER UPGLIDE OCCURS. AS THE LOW LIFTS NORTHWARD
AND BECOMES VERTICALLY STACKED OVERNIGHT...A DECENT FGEN BAND IS
PROGGED TO DEVELOP OVER MUCH OF THE CENTRAL AND EASTERN U.P. THIS
WILL FOCUS STRONG QCONV OVER THESE AREAS ALONG WITH THE DEEP LAYER
1000 TO 500MB RH TO LEND SUPPORT TO A STEADY...MODERATE TO
OCCASIONALLY HEAVY RAINFALL ACROSS THE AREA. PWAT VALUES ARE
EXPECTED TO BE AROUND 1 TO 1.5 INCHES ACROSS THE AREA...AGAIN
LENDING SUPPORT TO A DECENT RAINFALL. AS THE LOW WORKS SLOWLY EAST
NORTHEASTWARD INTO THE OHIO VALLEY THROUGH WEDNESDAY EXPECT THE LOW
TO WEAKEN. THE INVERTED TROUGH ASSOCIATED WITH THIS LOW WILL LINGER
OVER MUCH OF THE EASTERN U.P. THROUGH THIS TIME FRAME ALONG WITH
WEAK QCONV ALLOWING RAIN SHOWERS TO CONTINUE THROUGH THIS TIME
PERIOD. DRY AIR WILL BEGIN WORKING INTO THE NORTHWEST PORTION OF THE
U.P. TUESDAY MORNING ALLOWING SHOWERS TO TAPER OFF A BIT EARLIER
OVER THOSE AREAS.
AN ADDITIONAL CONCERN...ESPECIALLY DURING THE TUESDAY INTO TUESDAY
NIGHT TIME PERIOD IS THE POSSIBILITY FOR LARGE WAVES TO DEVELOP ON
THE TIGHTER PRESSURE GRADIENT ALONG THE INVERTED TROUGH. THESE WAVES
WOULD DEVELOP ON GUSTY NORTH TO NORTHEASTERLY WINDS....ALLOWING
WAVES TO REACH AROUND 8 FEET. THIS COULD CAUSE MINOR BEACH EROSION
ALONG THE MARQUETTE AND ALGER COUNTY SHORELINES.
WEDNESDAY NIGHT INTO THURSDAY NIGHT...MODEL TRENDS BEGIN TO DIVERGE
ON THE OVERALL TIMING AND POSITION OF THE UPPER LEVEL TROUGH AND
SURFACE LOW SHIFTING TO THE EAST OF THE UPPER PENINSULA.
CURRENTLY...IT APPEARS AS IF MOST OF THE U.P. WILL ONLY SEE LIGHT
RAIN SHOWERS THROUGH THIS TIME PERIOD AS OVERALL FORCING IS FAIRLY
WEAK AND MOISTURE IS NOT AS ABUNDANT.
FRIDAY THROUGH THE REMAINING EXTENDED...BROAD UPPER LEVEL TROUGHING
IS PROGGED TO DEVELOP OVER MUCH OF THE EASTERN U.S. ALLOWING FOR
INTERMITTENT RAIN SHOWERS TO DEVELOP ACROSS THE AREA. PINNING DOWN
SPECIFICS WILL BE A BIT TOUGH AT THIS POINT AS INCREASED RAINFALL
POTENTIAL WILL BE CLOSELY RELATED TO TIMING OF SHORTWAVES ROTATING
AROUND THE UPPER LEVEL 500MB TROUGH. AGAIN MODELS VARY SIGNIFICANTLY
ON THE FINER DETAILS AT THIS POINT THEREFORE...WILL STICK CLOSELY TO
MODEL CONSENSUS DURING THIS TIME FRAME. ON SUNDAY...MODELS ARE
TRENDING TOWARD A RIDGE BUILDING IN TO THE AREA...WHICH WOULD BEGIN
TO LEND MORE SUPPORT TO A BIT WARMER AND DRIER WEATHER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 121 AM EDT MON OCT 13 2014
SOME ISOLATED SHOWERS CONTINUE ACROSS UPPER MICHIGAN...HOWEVER THEY
ARE VERY LIGHT AS THE LOW LEVELS REMAIN DRY. AN AREA OF MVFR OR EVEN
IFR CONDITIONS ACROSS IOWA AND SRN WI ARE EXPECTED TO MOVE INTO
UPPER MICHIGAN LATE TONIGHT INTO MON MORNING. MOST LIKELY...THE CIGS
WILL STAY MVFR AS OPPOSED TO IFR DURING THE DAY ON MONDAY. A FRONTAL
BOUNDARY WILL APPROACH FROM THE WEST DURING THE DAY ON MONDAY...AND
LOW PRESSURE WILL DEVELOP ALONG THE FRONT OVER THE SOUTHERN PLAINS.
THIS LOW WILL MOVE TOWARD THE GREAT LAKES MON/MON NIGHT. DEEPER
MOISTURE WILL SPREAD ACROSS THE AREA LATE MONDAY INTO MONDAY
NIGHT...ALONG WITH RAIN. IFR CONDITIONS SHOULD PREVAIL MONDAY NIGHT
ACROSS THE ENTIRE AREA...AND IT WOULD NOT BE SURPRISING IF SOME LIFR
CONDITIONS DEVELOP MONDAY NIGHT.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 414 PM EDT SUN OCT 12 2014
SOUTHERLY WINDS AS HIGH AS 15-25KT WILL CONTINUE INTO THE EVENING
OVER ROUGHLY THE E HALF OF LAKE SUPERIOR. PRES GRADIENT THEN WEAKENS
OVERNIGHT/MON AS A LOW PRES TROF MOVES E INTO THE UPPER LAKES WHILE
LOW PRES ORGANIZES ALONG THE TROF OVER THE SOUTHERN PLAINS. THIS
WILL RESULT IN WINDS DIMINISHING OVERNIGHT AND MON. WINDS WILL BE
UNDER 10KT ACROSS THE LAKE BY MON AFTN. AS THE LOW SLOWLY LIFTS
NE...WINDS WILL BECOME N TO NE MON NIGHT AND WILL INCREASE LATE. TUE
AND TUE NIGHT...EXPECT N TO NE WINDS UP TO 20KT ON WRN LAKE SUPERIOR
AND UP TO 25KT ON ERN LAKE SUPERIOR. THE LOW WILL THEN WEAKEN AS IT
DRIFTS NE ACROSS THE GREAT LAKES REGION WED/THU...ALLOWING WINDS TO
DIMINISH. WINDS SHOULD BE UNDER 10KT BY THU. ANOTHER LOW PRES SYSTEM
TRACKING ACROSS SRN CANADA THU WILL THEN MERGE WITH THE REMNANT
GREAT LAKES LOW ON FRI IN THE VCNTY OF JAMES BAY. THIS WILL RESULT IN
INCREASING W TO NW INTO THE 15-25KT RANGE ON FRI.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...MRD
SHORT TERM...ROLFSON
LONG TERM...KEC
AVIATION...MRD
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
355 AM CDT Mon Oct 13 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 355 AM CDT Mon Oct 13 2014
Warm front extending from near Joplin to Jefferson City and through
the St. Louis Metro area northeast to near Decatur will continue to
lift slowly north today as a strong trof and associated wound up
surface low moves northeast through Missouri. Strong low level warm
advection ahead of the system will produce scattered to numerous
showers and thunderstorms this morning. All short-range guidance is
very consistent in developing a wave of convection this morning
with a break before another round this afternoon. With some dry
time and a bit of insolation, MUCAPE in excess of 1000 J/Kg should
result. Very strong wind fields and plenty of shear will likely
produce severe thunderstorms this afternoon...primarily along and
east-southeast of the I-44 corridor. 4km NSSL and NCEP WRF models
along with the HRRR develop a strong squall line which moves rapidly
east this afternoon. SPC day 1 outlook has about the southeast 1/2
to 2/3 of the area in a slight risk with the moderate clipping
Reynolds, Iron and Madison counties. Primary concern will be
damaging winds given the very strong wind fields, and there could be
a few tornadoes as 0-1km helicity is forecast to be in excess of 200
m2/s2. Lack of steep lapserates aloft precludes a high hail risk.
Carney
.LONG TERM: (Tonight through Sunday)
Issued at 355 AM CDT Mon Oct 13 2014
A strong storm system is still set to deepen and slowly move through
our region over the next few days. It will initially close off this
evening over far southwestern MO and then not begin to pull away
from our region to the east until Wednesday, but its influences will
still be felt thru Wednesday night and perhaps into Thursday.
The main severe thunderstorm threat from this system will be on its
front-end, and is expected to be ongoing early this evening from the
lower MS Valley into southern IL. The convective mode by this time
is expected to be a squall line with damaging winds and isolated
imbedded tornadoes. All indications, though, is that the severe
thunderstorm threat should end by 9pm across our region as it pushes
east.
Heading into late tonight and through Wednesday, the primary focus
at this point will be the deformation zone pcpn, which will be best
focused down our way using the expected location of the TROWAL and
decently strong lo-level convergence. With a system this wrapped up
expected, went above MAV MOS PoPs, tapering back to MOS by Wednesday
night. Added in some small mentionable PoPs for Thursday in parts
of southern IL with the trends all heading in that direction, with
stronger indications of more persistent, deep cyclonic flow.
MOS temps thru Wednesday look reasonable, but adjusted daytime maxes
a bit lower where we expect the most peristent, and high, rain
chances to be.
Northwest upper flow is still on track for late week and next
weekend, with a couple of glancing blows from upper level
disturbances on Friday and Sunday, but moisture looks severely
limited enough to hold off on chance mention for now. Temps should
be near seasonal normals.
TES
&&
.AVIATION: (For the 06z TAFs through 06z Monday Night)
Issued at 1126 PM CDT Sun Oct 12 2014
Expect TSRA to develop S of terminals over the next few hours and
gradually move nwd thru the morning hours. Believe there will be a
brief period of dry time before another round of TSRA impact the
terminals. UIN may see more stratiform precip rather than a line
of TSRA, but some uncertainty remains. Cigs/vsbys shud improve as
the wrmfnt lifts nwd, before lowering again with TSRA. Expect dry
slot behind the line of TSRA before RA move in with the sfc low.
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
317 AM CDT MON OCT 13 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 316 AM CDT MON OCT 13 2014
MAIN FORECAST CONCERNS WILL BE ENDING PRECIPITATION THIS MORNING AND
WINDS FOR TODAY.
LATEST RADAR TRENDS SHOW SHOWERS IN THE WESTERN PART OF THE FORECAST
AREA THAT ARE MOVING SOUTH AND ANOTHER AREA OF SHOWERS TO THE
SOUTHEAST THAT IS MOVING TO THE NORTH. SURFACE ANALYSIS HAS A COLD
FRONT JUST ABOUT TO EXIT THE FAR SOUTHEAST PART OF THE FORECAST AREA
ALREADY THIS MORNING.
SHORT TERM MODELS HAVE A VARIETY OF SOLUTIONS FOR THE CURRENT
PRECIPITATION. THE HRRR AND RAP TRY TO BRING THE SHOWERS TO THE
SOUTHEAST NORTH INTO THE FORECAST AREA...BUT THE TREND ON THESE HAVE
BEEN TO WEAKEN A LITTLE AS THEY MOVE TO THE NORTH. ON THE OTHER HAND
THE 4KM WRF KEEPS IT MOSTLY TO THE SOUTHEAST OF THE AREA. THE
PRECIPITATION TO THE WEST IS NOT HANDLED WELL WITH THE MODELS. WITH
THAT IN MIND...HAVE KEPT POPS IN THE SOUTHERN/SOUTHEASTERN PART OF
THE FORECAST AREA THROUGH THE MORNING HOURS...BUT LOWERED THE
CHANCES. HAVE KEPT THUNDER OUT SINCE THE MUCAPE IS NON-EXISTENT AND
THERE HAS ONLY BEEN A RARE LIGHTNING STRIKE IN THE PAST COUPLE OF
HOURS.
NORTH OR NORTHWEST WINDS HAVE ALREADY STARTED INCREASING THIS
MORNING. MOST LOCATIONS HAVE WINDS AT 15 TO 20 MPH WITH GUSTS TO
AROUND 25 MPH ALREADY. EXPECT THE TREND TO INCREASE AND AS THE SUN
RISES THIS MORNING AND THE INVERSION BREAKS STRONGER WINDS WILL MIX
DOWN. WINDS AT 850MB ARE STRONGEST AT 12Z THIS MORNING...BUT REMAIN
AROUND 40 KNOTS THROUGH THE AFTERNOON. WILL KEEP THE WIND ADVISORY
THROUGH THE DAY.
AS THE SUN SETS THIS EVENING...WINDS WILL DROP OFF BUT STILL REMAIN
BREEZY FOR A COUPLE OF HOURS. LATER TONIGHT A SURFACE HIGH PRESSURE
SYSTEM WILL START TO BUILD INTO THE AREA AND WINDS WILL DIMINISH.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 316 AM CDT MON OCT 13 2014
GUIDANCE SUGGESTS THE LONG TERM FORECAST PERIOD WILL START WITH AN
UPPER TROPOSPHERIC TROUGH OVER CENTRAL AND EASTERN PORTIONS OF THE
CONUS...AND A RIDGE OVER THE WEST. THE RIDGE OVER THE WEST IS
EXPECTED TO MOVE EAST INTO THE CENTRAL CONUS ON WEDNESDAY...BEFORE
WEAKENING THUS ALLOWING FOR QUASI-ZONAL UPPER TROPOSPHERIC FLOW OVER
OUR AREA ON THURSDAY. A STRENGTHENING UPPER TROPOSPHERIC TROUGH OVER
THE GREAT LAKES REGION IS THEN EXPECTED TO TURN OUR FLOW MORE
NORTHWESTERLY FRIDAY THROUGH SUNDAY.
AN OVERALL LACK IN OMEGA SHOULD PROMOTE DRY CONDITIONS TO OUR AREA AS
THE AFOREMENTIONED UPPER TROPOSPHERIC RIDGE AXIS MOVES OVER THE
REGION. SUCH HAS BEEN PRESENTED IN THE OFFICIAL FORECAST. ONE COULD
ARGUE THAT THE PASSAGE OF A WEAK UPPER TROPOSPHERIC PERTURBATION...OR
PERHAPS ENHANCED JET DYNAMICS...COULD BRING CHANCES FOR LIGHT
PRECIPITATION TO THE REGION THURSDAY ONWARD...BUT AT THIS TIME
TROPOSPHERIC MOISTURE APPEARS AS THOUGH IT WILL BE EXTREMELY LACKING
THURSDAY THROUGH SUNDAY AND AS A RESULT...ALSO WENT AHEAD WITH DRY
CONDITIONS THROUGH THE WEEKEND.
SOUTHERLY BOUNDARY-LAYER RETURN FLOW IS EXPECTED TO OVERTAKE THE
REGION STARTING ON WEDNESDAY AND AS A RESULT...THERMAL ADVECTION
THROUGH THE BOUNDARY LAYER SHOULD PROMOTE A GENERAL WARMING TREND
FROM DAY TO DAY BETWEEN TUESDAY AND THURSDAY...WITH HIGHS CLIMBING
FROM THE 60S ON TUESDAY TO THE LOW TO MID 70S BY THURSDAY. THE
PASSAGE OF A WEAK BOUNDARY-LAYER BAROCLINIC ZONE IS THEN EXPECTED TO
BRING A SLIGHT COOL DOWN TO FINISH THE FORECAST PERIOD...WITH HIGHS
BACK IN THE 60S FRIDAY THROUGH SUNDAY. TUESDAY NIGHT
/ WEDNESDAY MORNING LOWS IN THE MID TO UPPER 30S WILL ALSO BE SHORT
LIVED AS BOUNDARY-LAYER THERMAL ADVECTION OVERTAKES THE AREA...WITH
LOWS GENERALLY IN THE 40S THEN EXPECTED THROUGH THE REMAINDER OF THE
FORECAST PERIOD.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1214 AM CDT MON OCT 13 2014
THE COLD FRONT HAS MOVED THROUGH THE TERMINALS EARLY THIS MORNING
AND WINDS HAVE TURNED TO THE NORTHWEST AND STARTED TO INCREASE. IN
ADDITION...MVFR CEILINGS HAVE SETTLED INTO THE AREA. THE CEILINGS
SHOULD CONTINUE THROUGH DAY BREAK THEN GRADUALLY LIFT BEFORE
CLEARING. NORTHWEST WINDS ARE EXPECTED TO BE STRONG DURING THE DAY
THEN DIMINISH SOME THIS EVENING.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...WIND ADVISORY FROM 7 AM THIS MORNING TO 7 PM CDT THIS EVENING
FOR NEZ039>041-046>049-060>064-072>077-082>087.
KS...WIND ADVISORY FROM 7 AM THIS MORNING TO 7 PM CDT THIS EVENING
FOR KSZ005>007-017>019.
&&
$$
SHORT TERM...JCB
LONG TERM...BRYANT
AVIATION...JCB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1219 AM CDT MON OCT 13 2014
.UPDATE...
ISSUED AT 725 PM CDT SUN OCT 12 2014
UPDATED THE FORECAST THIS EVENING TO LOWER CHANCES OF PRECIP IN
SOUTHWESTERN PORTIONS OF OUR NEBRASKA COUNTIES AS MUCH OF THE RAIN
HAS CLEARED OFF TO THE EAST.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 224 PM CDT SUN OCT 12 2014
TONIGHT THROUGH MONDAY...MAIN ISSUES ARE PRECIPITATION ONGOING...
AND STRONG WINDS MONDAY.
THE AS ADVERTISED STRONG UPPER LEVEL SYSTEM CONTINUES TO BE ON TRACK
FOR RAPID STRENGTHENING AND CYCLOGENISIS ACROSS THE SOUTHERN PLAINS
THE NEXT 18-24 HOURS. INITIAL COLD FRONTAL SURGE IS CURRENTLY ACROSS
WESTERN NEBRASKA...APPROACHING THEDFORD AND NORTH PLATTE. THIS SEEMS
A BIT QUICKER GIVEN THE TENDENCY THE LAST DAY OR SO FOR THE MODELS
TO BE A BIT SLOWER OVERALL WITH DEVELOPING FEATURES. INITIAL ROUND
OF DIFFERENTIAL VORTICITY ADVECTION AND MID LEVEL WARM ADVECTION HAS
SPARKED A SLOW TO MOVE AREA OF SHOWERS AND ISOLATED THUNDERSTORMS
WHICH BEGAN FIRST THING THIS MORNING. COUPLE AUTOMATED WEATHER
STATIONS DID REPORT ABOUT ONE-QUARTER INCH OF RAIN IN PHILLIPS COUNTY
KANSAS...AND THIS HAS BEEN A STEADY EVENT ALTHOUGH THE LOW LEVELS
ARE VERY DRY WITH NEAR 40 DEWPOINTS OVER THE NORTHEAST FORECAST
AREA. RELYING ON THE HRRR AND ITS HANDLING...THIS PRECIPITATION
GRADUALLY MOVES NORTHEAST ACROSS THE FORECAST AREA THE NEXT FEW
HOURS...AND LOSES SOME STEAM AS IT MOVES THROUGH THE DRY AIR. THAT
IS TREND FOLLOWED IN THE FORECAST...ALONG WITH AN ISOLATED STORM
OR TWO.
MAIN PRECIPITATION CHANCE COMES LATER TONIGHT. AS THE COLD FRONT
FIRES UP THE DEEPENING LOW WITH INCREASING BAROCLINICITY...A CLASSIC
DEFORMATION AXIS SETS UP ON THE NORTHWEST SIDE OF THE MAIN UPPER
LEVEL LOW. SOME 12Z MODELS /WRF-NAM/ NOW HOLD THAT AXIS FURTHER
NORTHWEST AND IMPLY A STEADY RAIN IS POSSIBLE EVEN IN THE HASTINGS
AREA. OTHER MODELS CONTINUE TO OFFER THE RAIN JUST A BIT FURTHER
SOUTHEAST...BUT SOLIDLY ACROSS NORTH CENTRAL KANSAS...AND SOUTHEAST
OF A YORK TO RED CLOUD LINE LATE TONIGHT AND EARLY MONDAY. THAT IS
WERE THE HIGHEST PRECIPITATION CHANCES HAVE BEEN...AND CONTINUE TO
BE TONIGHT AND EARLY MONDAY. IT IS IMPORTANT TO NOTE...THERE WILL
BE AN EXTREMELY SHARP CUTOFF FROM RAIN TO NO-RAIN PROBABLY SOUTHEAST
OF HASTINGS. IN THE RAIN AREA...ITS A SOLID CHILLY RAIN...BUT WILL
END ABOUT AS ABRUPTLY AS IT CAN AT SOME POINT ON ITS NORTHWEST EDGE.
RAIN AMOUNTS COULD BE DECENT IN THIS BAND...ALTHOUGH ITS HARD TO
SELL OUT GIVEN THE EXACT BAND LOCATION WILL NOT BE KNOW FOR SEVERAL
HOURS. THE RAIN WRAPS UP BY MIDDAY IN THE EASTERN FORECAST AREA...
AND CLEARING SKIES WILL PULL EAST NICELY BY AFTERNOON.
THE OTHER MAIN STORY ON MONDAY IS THE WIND. DEEPENING LOW...GOOD
MIXING...NICE UNI-DIRECTIONAL SHEAR...ALL POINT TO STRONG MOMENTUM
TRANSFER DOWNWARD OF STRONG WINDS. GUST POTENTIAL IN THE 50 MPH IS
POSSIBLE...ESPECIALLY IN THE LATE MORNING/MIDDAY TIMFRAME ACROSS
FAR SOUTHERN NEBRASKA AND NORTH CENTRAL KANSAS IN THE LATE MORNING
AND MIDDAY AREAS. HOISTED A WIND ADVISORY FOR THE DAY MONDAY. IT MAY
NOT BE A SLAM DUNK IN THE NORTHEAST AREAS...AND BEGINNING AND ENDING
TIMES ARE NOT WELL ALIGNED ACROSS THE FORECAST AREA...BUT CONSENSUS
AMONG US AND SEVERAL KANSAS OFFICES WAS A WIND ADVISORY. ADVISORY
STARTS AT 7 AM AND ENDS AT 7 PM MONDAY FOR ALL AREAS TO MAKE THINGS
EASY.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 224 PM CDT SUN OCT 12 2014
MONDAY NIGHT THROUGH SUNDAY.
STARTING OUT MONDAY NIGHT...THE PATTERN ALOFT WILL BE AMPLIFIED WITH
AN UPPER TROUGH MOVING INTO THE PACIFIC NW...RIDGING OVER THE
ROCKIES...A TROUGH IN THE INTERIOR CONUS ACROSS THE PLAINS GENERALLY
ALONG THE MO RIVER...AND UPPER RIDGING IN THE ATLANTIC OCEAN. IN A
TIGHT SURFACE PRESSURE GRADIENT WITH THE SFC LOW IN IOWA...NORTH
WINDS WILL REMAIN STRONG/GUST FOR A COUPLE OF HOURS DURING THE
EVENING BEFORE DECOUPLING.
THE UPPER TROUGH CONTINUES TO EXIT TO THE EAST MONDAY NIGHT AND
TUESDAY WITH RISING HEIGHTS AND WARMER AIR WORKING ONTO THE PLAINS
AS THE UPPER RIDGE AXIS OVER THE ROCKIES REACHES THE HIGH PLAINS. THE
LLVL PRESSURE GRADIENT WILL NOT BE AS TIGHT ON TUESDAY HOWEVER
FORECAST SOUNDING INDICATE MIXING TO H85 WITH WINDS AT THE TOP OF
THE LAYER AROUND 25KTS THRU THE MORNING AND AROUND 20KTS IN THE AFTN
SO DO EXPECT SOME BREEZY NORTH WINDS AT TIMES ESPECIALLY FOR THE
FIRST PART OF THE DAY. DAYTIME TEMPERATURES ARE STILL LOOKING
SEASONAL WITH HIGHS AVERAGING IN THE MID 60S.
BOTH MONDAY NIGHT AND TUESDAY NIGHTS LOOK TO BE THE COLDEST OF THE
EXTENDED PERIODS. SFC DPS DROP TO THE LOW/MID 30S AND LOW TEMPS IN
THE 30S ARE POSSIBLE...ESPECIALLY ACROSS PORTIONS OF SOUTH CENTRAL
NEBRASKA. WIND SPEEDS BE LIGHTER TUESDAY NIGHT VS MONDAY NIGHT
UNDER INFLUENCE OF SURFACE RIDGE AND FROST DEVELOPMENT MAY OCCUR.
SINCE THE LOWER TEMPS WILL MATERIALIZE IN AREAS WHICH ALREADY
FROZE...WILL NOT INCLUDE FROST MENTION IN GRIDS/HWO ATTM.
THE MIDDLE OF THE WEEK WILL SEE THE UPPER RIDGE DEAMPLIFY AS IT
MIGRATES ONTO THE PLAINS DUE TO ENERGY TRANSLATING FM THE PACIFIC NW
ACROSS THE US/CANADIAN BORDER. AHEAD OF AN APPROACHING COLD
FRONT...TEMPS WILL MAKE A RUN NEAR OR INTO THE 70S ON WEDNESDAY.
THE COLD FRONTAL BOUNDARY PUSHES SOUTH EARLY THURSDAY...WITH OVERALL
COOLING BEHIND THE FRONT NEGLIGIBLE AND TEMPS GRADUALLY RETURN
CLOSER TO SEASONAL NORMS. THE NORTHERN CONUS SYSTEM DEEPENS IN
ONTARIO FOR THE LATTER PART OF THE WORKWEEK WITH FLOW ACROSS THE
PLAINS TRANSITIONING MORE NORTHWESTERLY FOR A TIME. THERE ARE SOME
MODEL DIFFERENCES IN HANDLING THIS TROUGH AS WELL AS THE WESTERN
RIDGE AND DID NOT DEVIATE FROM EXTENDED INIT. FOR THE MOST PART THE
WEEKEND IS LOOKING MAINLY DRY ALTHOUGH MODELS HINT AS SOME LIGHT
PCPN DEVELOPMENT ON SUNDAY BUT THIS IS NOT CLEAR CUT. MAINLY DRY
CONDITIONS AND FAIRLY SEASONAL TEMPS STILL LOOK REASONABLE FOR THE
EXTENDED FORECAST PERIODS.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1214 AM CDT MON OCT 13 2014
THE COLD FRONT HAS MOVED THROUGH THE TERMINALS EARLY THIS MORNING
AND WINDS HAVE TURNED TO THE NORTHWEST AND STARTED TO INCREASE. IN
ADDITION...MVFR CEILINGS HAVE SETTLED INTO THE AREA. THE CEILINGS
SHOULD CONTINUE THROUGH DAY BREAK THEN GRADUALLY LIFT BEFORE
CLEARING. NORTHWEST WINDS ARE EXPECTED TO BE STRONG DURING THE DAY
THEN DIMINISH SOME THIS EVENING.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...WIND ADVISORY FROM 7 AM THIS MORNING TO 7 PM CDT THIS EVENING
FOR NEZ039>041-046>049-060>064-072>077-082>087.
KS...WIND ADVISORY FROM 7 AM THIS MORNING TO 7 PM CDT THIS EVENING
FOR KSZ005>007-017>019.
&&
$$
UPDATE...HEINLEIN
SHORT TERM...NOAA/NWS/MORITZ
LONG TERM...FAY
AVIATION...JCB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1153 PM CDT SUN OCT 12 2014
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY)
ISSUED AT 154 PM CDT SUN OCT 12 2014
MAIN FORECAST CONCERN WILL BE TIMING AND EXTENT OF PRECIP
ASSOCIATED WITH SYSTEM MOVING ACROSS THE SOUTHERN PLAINS
TONIGHT THROUGH TUESDAY.
RADAR SHOWING AREA OF SHOWERS AND THUNDERSTORMS OVER SOUTH CENTRAL
NEBRASKA LIFTING TOWARD NORTHEAST NEBRASKA AT 19Z. ALTHOUGH 12Z
MODELS SHOW SOME RAIN MOVING ACROSS THE AREA TONIGHT AND MONDAY
THE BETTER CHANCE OF SIGNIFICANT RAINFALL LOOKS TO STAY SOUTH AND
EAST OF THE CWA. LATEST RAP AND HRRR ALSO SHOW THIS TREND THROUGH
THE EVENING WITH BETTER FORCING AND INSTABILITY LOCATED TO THE
SOUTH.
HAVE ADJUSTED WEATHER DURING THIS TIME BY REMOVING MODERATE
CATEGORY OF RAIN AND KEPT JUST LIGHT SHOWERS TO REFLECT THIS
LATEST MODEL SOLUTION. SOME ISOLATED THUNDER IS POSSIBLE THIS
EVENING ALONG THE SOUTHEAST BORDER WHERE SOME INSTABILITY IS
INDICATED THROUGH 06Z. PRIMARY IMPACT WITH THIS SYSTEM LOOKS TO BE
WIND BEHIND THE FRONT AS IT MOVES THROUGH THE AREA. INCREASING
NORTH WINDS ARE EXPECTED TO MOVE INTO WESTERN PARTS OF THE AREA
AFTER 06Z TONIGHT THEN SPREAD EAST ACROSS THE REST OF THE CWA ON
MONDAY. AT THIS TIME IT APPEARS THE STRONGEST WINDS WILL STAY JUST
WEST OF THE CWA ON MONDAY SO NO WIND HEADLINES FOR NOW. LATER
SHIFTS WILL REEVALUATE FOR ANY CHANGE TO THAT THINKING.
WINDS WILL BE DECREASING DURING THE DAY ON TUESDAY ONCE SYSTEM
MOVES EAST OF THE AREA TOWARD THE LOWER GREAT LAKES. TEMPERATURES
WILL BE COOL ON MONDAY DUE TO CLOUDS AND RAIN BUT THINGS WARM UP
QUICKLY TUESDAY INTO WEDNESDAY AS AN UPPER RIDGE MOVES OVER THE
CENTRAL PART OF THE NATION...ALTHOUGH 12Z ECMWF HOLDS ON TO THE
UPPER LOW OVER THE MID MISSISSIPPI VALLEY LONGER THAN THE NAM OR
GFS WHICH COULD KEEP CLOUDS OVER EASTERN PARTS OF THE AREA IF
THIS SOLUTION WORKS OUT.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 154 PM CDT SUN OCT 12 2014
EXTENDED MODELS SHOW SOME DIFFERENCE IN HANDLING OF THE UPPER
FEATURES DURING THE PERIOD...SO SOME UNCERTAINTY IN THIS PART OF
THE FORECAST. PRIMARY TREND AT THIS TIME LOOKS TO BE DRY WITH
SEASONAL TEMPERATURES.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1148 PM CDT SUN OCT 12 2014
INITIAL BAND OF -RA HAS MOVED THROUGH THE TAFS. COLD FRONT IS
CURRENTLY MOVG THRU KOFK AND WILL MOV THROUGH KOMA/KLNK BY 08Z.
ALONG THE COLD FNT WE SHOULD CONT TO SEE SOME -DZ/-RA AT ALL 3
SITES FOR A FEW MORE HOURS. CIGS WILL BE A BIT VARIABLE AT KOFK FM
VFR TO MVFR...BUT MORE CONSISTENT MVFR CIGS ARE EXPECTED AT
KOMA/KLNK OVERNIGHT. WINDS WILL CONT TO INCREASE ON MON FM THE NW
WITH GUSTS LIKELY AT ALL 3 SITES. LATEST GUIDANCE INDCS BAND OF
-RA MAY BE SOUTH OF KOMA/KLNK ON MON MRNG BUT WL INCLUDE A TEMPO
GROUP FOR A FEW HOURS. OTHERWISE WE SHOULD SEE SOME IMPROVEMENT TO
VFR CONDS BY LATE AFTN AT KOMA/KLNK BUT CONT WITH A BKN MID LEVEL
DECK THRU THE END OF THE PERIOD.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...FOBERT
LONG TERM...FOBERT
AVIATION...
AREA FORECAST DISCUSSION
NWS BUFFALO NY
431 AM EDT MON OCT 13 2014
.SYNOPSIS...
A WARM FRONT WILL MOVE NORTH ACROSS THE REGION TODAY BRINGING A
FEW LIGHT SHOWERS AND MILD TEMPERATURES. TEMPERATURES WILL SOAR
WELL ABOVE NORMAL ON TUESDAY WITH MAINLY DRY WEATHER. A COLD FRONT
WILL THEN SLOWLY CROSS THE REGION WEDNESDAY WITH SHOWERS AND
POSSIBLY A THUNDERSTORM. SHOWERS WILL CONTINUE THURSDAY AS LOW
PRESSURE MOVES JUST NORTH OF THE AREA WITH TEMPERATURES GRADUALLY
COOLING BACK TO NEAR AVERAGE BY NEXT WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE WAS SITUATED OFF THE SOUTHERN NEW ENGLAND COAST
THIS MORNING. STRENGTHENING RETURN FLOW OVERSPREADING WESTERN NEW
YORK RESULTING IN INCREASING CLOUD COVER AND RISING TEMPERATURES.
REGIONAL RADARS SHOWING LITTLE IN THE WAY OF SHOWER ACTIVITY OTHER
THAN A FEW SPRINKLES AT THIS POINT SUGGESTING WEAK LARGE SCALE
FORCING.
WARM AIR/MOISTURE ADVECTION WILL BE MAINTAINED TODAY AS DIFFUSE
WARM FRONT MOVES NORTHWARD INTO THE REGION. FORCING WILL REMAIN
VERY LIMITED WITH ONLY A FEW LIGHT SHOWERS EXPECTED. THIS IS
SUPPORTED BY LATEST HRRR RUNS SHOWING VERY LIMITED ACTIVITY
THROUGH THE DAY TODAY.
TEMPERATURES TODAY LOOK TO BE AT LEAST 10 DEGREES ABOVE NORMAL AS
850MB TEMPERATURES RISE TO AROUND +11C TO +13C BY AFTERNOON...
SUPPORTING HIGHS IN THE LOWER 70S ACROSS LOWER ELEVATIONS FROM
THE GENESEE VALLEY WESTWARD...WITH 60S MORE PREVALENT ACROSS THE
SOUTHERN TIER AND NORTH COUNTRY.
TONIGHT...THERE STILL COULD BE A FEW WARM ADVECTION DRIVEN SHOWERS
BUT FOR THE MOST PART CLOUDY SKIES EXPECTED. TEMPERATURES REMAINING
MILD UNDERNEATH CLOUDS AND SOUTHERLY FLOW WITH LOWS ONLY DROPPING
INTO THE UPPER 50S TO LOWER 60S.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
IT WILL BE UNSEASONABLY MILD AND INCREASINGLY UNSETTLED DURING THIS
PERIOD AS A HIGHLY AMPLIFIED PATTERN...FEATURING AN ANOMALOUSLY DEEP
(-3 STD) TROUGH OVER THE MISSISSIPPI VALLEY...WILL GENERATE A 555DM
CLOSED LOW OVER THE OHIO VALLEY. THIS DOMINANT BLOCK WILL REMAIN TO
OUR WEST THROUGH THIS PERIOD...SO BEING ON THE `WARM` SIDE OF THE
FEATURE...OUR FORECAST AREA WILL BE GUARANTEED TO EXPERIENCE ABOVE
NORMAL TEMPERATURES. IN FACT...TEMPERATURES ON TUESDAY WILL BE
DOWNRIGHT SUMMER LIKE WITH READINGS MORE TYPICAL OF LATE JULY/EARLY
AUGUST. WHILE THE MERCURY WILL TREND LOWER AFTER THAT POINT...THEY
WILL MOST CERTAINLY REMAIN ABOVE NORMAL THROUGH AT LEAST THURSDAY.
BY THE TIME WE OPEN THIS PERIOD ON TUESDAY...A MID LEVEL
CIRCULATION WILL HAVE ALREADY TAKEN SHAPE OVER MISSOURI. ITS
ATTENDANT SUB-1000MB SFC LOW OVER ILLINOIS WILL LIKELY OCCLUDE BY
THE END OF THE DAY...MARKING THE PEAK STRENGTH OF THE OVERALL
SYSTEM. MEANWHILE DOWNSTREAM..A 40KT SOUTHERLY LOW LEVEL JET WILL
PUMP H85 TEMPS OF +15/16C ACROSS OUR FORECAST AREA. BEING DEEP
WITHIN THE WARM SECTOR OF THE STORM SYSTEM...THIS WILL SEND OUR
AFTERNOON HIGHS TO BETWEEN 75 AND 80...WITH THE VALLEYS AND LAKE
PLAINS WEST OF ROCHESTER LIKELY PUSHING INTO THE LOWER 80S. THE
ANOMALOUSLY STRONG SOUTHERLY FLOW WILL NOT ONLY HELP TO PRODUCE
UNUSUAL WARMTH ACROSS OUR REGION...BUT WILL KEEP PCPN FROM THE
AFOREMENTIONED SYSTEM WELL TO OUR WEST.
THE MATURE...VERTICALLY STACKED SYSTEM WILL BE CENTERED OVER
ILLINOIS TUESDAY NIGHT WHILE AN OCCLUDED SFC FRONTAL BOUNDARY WILL
STRETCH SOUTHWARDS ALONG THE SPINE OF THE APPALACHIANS. A 45-50KT
LOW LEVEL JET AHEAD OF THE SYSTEM WILL CONTINUE TO RETARD THE
EASTWARD PROGRESSION OF THE ASSOCIATED SHOWER ACTIVITY OVER OUR
REGION...SO WILL CONTINUE THE TREND OF SLOWING THE ONSET OF PCPN.
WILL BACK OFF POPS TO CHC FOR THE WESTERN COUNTIES AND SLGT CHC FOR
EASTERN LAKE ONTARIO REGION. WHILE THE STRONG LLJ WILL TEMPORARILY
KEEP THE PCPN TO OUR WEST...IT WILL ADVECT PWAT VALUES OF 1.5 TO
1.75" INTO OUR AREA FOR LATE TUESDAY NIGHT AND WEDNESDAY...SETTING
THE STAGE FOR A POTENTIALLY VERY WET 18 HOUR PERIOD. TUESDAY NIGHT
LOWS WILL GENERALLY RANGE FROM 60 TO 65...WHICH WILL BE SOME 20
DEGREES F ABOVE NORMAL. ANOTHER WAY OF LOOKING AT THE ANOMALOUS
NATURE OF THESE VALUES IS THAT THEY WILL ACTUALLY BE NOTABLY HIGHER
THAN WHAT THE DAYTIME HIGHS SHOULD BE FOR THIS TIME OF YEAR.
ON WEDNESDAY...THE STACKED LOW WILL SLOWLY CROSS THE MID WEST WHILE
THE AXIS OF DEEPEST MOISTURE ASSOCIATED WITH ITS SFC OCCLUDED FRONT
WILL PUSH ACROSS THE WESTERN COUNTIES OF NEW YORK. GIVEN PWAT VALUES
IN THE VCNTY OF 1.75"...LIFT PROVIDED BY A STRONGLY DIVERGENT UPPER
LEVEL FLOW AND 40+KT LOW LEVEL JET JUST AHEAD OF THE OCCLUDED FRONT
SHOULD PRODUCE WIDESPREAD SHOWERS WITH RAINFALL LIKELY REACHING A
HALF TO ONE INCH OVER THE WESTERN COUNTIES. WHILE THE AIRMASS WILL
ONLY BE MARGINALLY UNSTABLE...THE SYNOPTIC FORCING COULD BE ENOUGH
TO TOUCH OFF AN EMBEDDED THUNDERSTORM OR TWO. WILL USE CAT POPS OVER
THE WESTERN COUNTIES AND LIKELY EAST OF LK ONTARIO.
THE CLOSED LOW WILL SLOWLY START TO OPEN UP AS IT MAKES ITS WAY TO
SOUTHERN LOWER MICHIGAN WEDNESDAY NIGHT...WHILE THE SFC OCCLUSION
WILL MAKE ITS WAY ACROSS OUR FINGER LAKES REGION. THIS WILL PLACE
SITES FROM THE FINGER LAKES EAST IN THE PRIME AREA FOR WIDESPREAD
SHOWERS...WITH THE ACTIVITY OVER THE FAR WESTERN COUNTIES TAPERING
OFF DURING THE COURSE OF THE NIGHT AS A DRY SLOT WORKS IN BEHIND THE
OCCLUSION.
THE FILLING UPPER LEVEL STORM SYSTEM WILL PUSH NORTH ACROSS LOWER
MICHIGAN ON THURSDAY...WHILE ITS SUPPORTING LONGWAVE TROUGH WILL
BECOME NEGATIVELY TILTED OVER THE LOWER GREAT LAKES. AT THE SFC...
THE OCCLUSION WILL EXIT THE EASTERN LAKE ONTARIO REGION...BUT NOT
BEFORE PRODUCING A FEW MORE HOURS OF SHOWERS DURING THE MORNING.
WHILE SYNOPTIC MOISTURE WILL ROTATE BACK ACROSS THE LOWER GREAT
LAKES BEHIND THE AFOREMENTIONED DRY SLOT...THERE WILL BE A LACK OF
ANY SIGNIFICANT FORCING MECHANISM TO SUPPORT MUCH IN THE WAY OF
SHOWERS WITHIN THE BASE OF THE UPPER LEVEL TROUGH...SO WILL ONLY USE
CHC POPS FOR THE WESTERN COUNTIES.
THE BASE OF THE NEGATIVELY TILTED LONGWAVE TROUGH WILL PUSH ACROSS
OUR FORECAST AREA THURSDAY EVENING BEFORE EXITING DURING THE
OVERNIGHT HOURS. LOW LEVEL RIDGING AND A GENERAL LACK OF ANY
SIGNIFICANT FORCING SHOULD NOT DO MUCH TO PROMOTE ANY ORGANIZED
SHOWER ACTIVITY...SO WILL BACK OFF ON POPS AND ONLY USE LOW CHC.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
THE WEATHER IS NOT EXPECTED TO BE NEARLY AS ACTIVE DURING THIS
PERIOD...ALTHOUGH WE CAN ANTICIPATE A TREND TOWARDS LOWER...MORE
SEASONABLE TEMPERATURES.
AS ENERGY WITHIN THE EXITING STORM SYSTEM PUSHES NORTH ACROSS QUEBEC
ON FRIDAY...A BROAD LONGWAVE TROUGH WILL BE LEFT ACROSS MUCH OF
EASTERN CANADA AND THE GREAT LAKES. THIS TROUGH WILL BECOME
RE-ENERGIZED (`RELOAD` IF YOU WILL) DURING THE COURSE OF THE DAY AS
A ROBUST SHORTWAVE OVER THE CANADIAN PRAIRIES WILL PUSH SOUTHEAST
ACROSS THE UPPER MISSISSIPPI VALLEY. THIS WILL LEAD TO SOME WEAK
RIDGING OVER THE LOWER GREAT LAKES...ENOUGH TO LIKELY KEEP THE DAY
RAIN FREE. H85 TEMPS ARND 8C WILL SUPPORT AFTERNOON HIGHS IN THE
60S.
THE AFOREMENTIONED SHORTWAVE WILL DIG INTO...AND THEREBY
SHARPEN...THE BASE OF THE LONGWAVE TROUGH OVER THE LOWER GREAT LAKES
LATE FRIDAY NIGHT AND SATURDAY. THIS SHOULD PUSH A COLD FRONT ACROSS
OUR REGION...PRODUCING SOME SCATTERED SHOWERS IN THE PROCESS.
BY SUNDAY...THE TROUGH WILL BE CENTERED OVER THE ST LAWRENCE VALLEY
WITH DEEP COLD ADVECTION OVER OUR REGION SENDING H85 TEMPS TO NEAR
2C. THIS WILL BE COLD ENOUGH TO CREATE SOME LAKE INDUCED INSTABILITY
WITH NUISANCE LAKE EFFECT RAIN SHOWERS EAST OF BOTH LAKES. HIGHS
SUNDAY AFTERNOON SHOULD ONLY BE IN THE LOW TO MID 50S.
&&
.AVIATION /09Z MONDAY THROUGH FRIDAY/...
VFR FLIGHT CONDITIONS WILL PREVAIL ACROSS MOST OF THE AREA THROUGH
THE TAF CYCLE...WITH THE EXCEPTION OF THE HIGHER TERRAIN.
WARM ADVECTION WILL INCREASE TODAY WHICH WILL HELP ADVECT LOW LEVEL
MOISTURE NORTHWARD INTO WESTERN AND CENTRAL NY...WITH ABUNDANT CLOUD
COVER CONTINUING THROUGH MUCH OF THE DAY TODAY. CIGS SHOULD BE
PRIMARILY LOW VFR ACROSS THE LOWER ELEVATIONS OF WESTERN NEW YORK AS
SOUTHERLY DOWNSLOPE WINDS INCREASE.
ACROSS THE HIGHER TERRAIN OF THE SOUTHERN TIER EXPECT MVFR CIGS TO
OVERSPREAD THE AREA AND LAST INTO AT LEAST THE FIRST HALF OF
MONDAY...WITH SOME IFR POSSIBLE ACROSS THE HIGHEST ELEVATIONS. LOW
VFR/MVFR CIGS ARE EXPECTED TO MOVE FURTHER NORTH ACROSS THE
KBUF/KIAG/KROC TERMINALS. FINALLY...LOW VFR CIGS WILL REACH KART
BY THIS MORNING. EXPECT MVFR CIGS ACROSS THE HIGHER TERRAIN...WITH
SOME IFR POSSIBLE ACROSS THE HIGHEST ELEVATIONS HERE AS WELL.
A WEAK LOW LEVEL JET WILL CROSS THE REGION THIS MORNING WITH WINDS
INCREASING TO AROUND 30 KNOTS JUST OFF THE DECK. IT APPEARS WIND
SPEEDS WILL NOT BE QUITE HIGH ENOUGH TO PRODUCE TRUE LOW LEVEL WIND
SHEAR.
OUTLOOK...
TUESDAY...MAINLY VFR.
WEDNESDAY...AREAS OF MVFR WITH SHOWERS LIKELY AND A CHANCE OF
THUNDERSTORMS.
THURSDAY...AREAS OF MVFR WITH SHOWERS LIKELY.
FRIDAY...VFR/MVFR WITH A CHANCE OF SHOWERS.
&&
.MARINE...
HIGH PRESSURE WILL DRIFT OFF THE NEW ENGLAND COAST TODAY AS LOW
PRESSURE MOVES SLOWLY FROM THE CENTRAL PLAINS TO THE WESTERN LAKES
BY WEDNESDAY. SOUTHERLY WINDS WILL INCREASE AHEAD OF THE LOW
TODAY...BUT CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY
CRITERIA THROUGH TUESDAY. SOUTHERLY WINDS WILL INCREASE FURTHER ON
TUESDAY NIGHT AND MAY BRING SMALL CRAFT ADVISORY LEVEL WINDS...
ALTHOUGH THE OFFSHORE WIND COMPONENT WILL KEEP THE GREATER WAVE
ACTION IN CANADA.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TMA
NEAR TERM...TMA
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...TMA
MARINE...TMA
AREA FORECAST DISCUSSION
NWS BUFFALO NY
425 AM EDT MON OCT 13 2014
.SYNOPSIS...
A WARM FRONT WILL MOVE NORTH ACROSS THE REGION TODAY BRINGING A
FEW LIGHT SHOWERS AND MILD TEMPERATURES. TEMPERATURES WILL SOAR
WELL ABOVE NORMAL ON TUESDAY WITH MAINLY DRY WEATHER. A COLD FRONT
WILL THEN SLOWLY CROSS THE REGION WEDNESDAY WITH SHOWERS AND
POSSIBLY A THUNDERSTORM. SHOWERS WILL CONTINUE THURSDAY AS LOW
PRESSURE MOVES JUST NORTH OF THE AREA WITH TEMPERATURES GRADUALLY
COOLING BACK TO NEAR AVERAGE BY NEXT WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE WAS SITUATED OFF THE SOUTHERN NEW ENGLAND COAST
THIS MORNING. STRENGTHENING RETURN FLOW OVERSPREADING WESTERN NEW
YORK RESULTING IN INCREASING CLOUD COVER AND RISING TEMPERATURES.
REGIONAL RADARS SHOWING LITTLE IN THE WAY OF SHOWER ACTIVITY OTHER
THAN A FEW SPRINKLES AT THIS POINT SUGGESTING WEAK LARGE SCALE
FORCING.
WARM AIR/MOISTURE ADVECTION WILL BE MAINTAINED TODAY AS DIFFUSE
WARM FRONT MOVES NORTHWARD INTO THE REGION. FORCING WILL REMAIN
VERY LIMITED WITH ONLY A FEW LIGHT SHOWERS EXPECTED. THIS IS
SUPPORTED BY LATEST HRRR RUNS SHOWING VERY LIMITED ACTIVITY
THROUGH THE DAY TODAY.
TEMPERATURES TODAY LOOK TO BE AT LEAST 10 DEGREES ABOVE NORMAL AS
850MB TEMPERATURES RISE TO AROUND +11C TO +13C BY AFTERNOON...
SUPPORTING HIGHS IN THE LOWER 70S ACROSS LOWER ELEVATIONS FROM
THE GENESEE VALLEY WESTWARD...WITH 60S MORE PREVALENT ACROSS THE
SOUTHERN TIER AND NORTH COUNTRY.
TONIGHT...THERE STILL COULD BE A FEW WARM ADVECTION DRIVEN SHOWERS
BUT FOR THE MOST PART CLOUDY SKIES EXPECTED. TEMPERATURES REMAINING
MILD UNDERNEATH CLOUDS AND SOUTHERLY FLOW WITH LOWS ONLY DROPPING
INTO THE UPPER 50S TO LOWER 60S.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
IT WILL BE UNSEASONABLY MILD AND INCREASINGLY UNSETTLED DURING THIS
PERIOD AS A HIGHLY AMPLIFIED PATTERN...FEATURING AN ANOMALOUSLY DEEP
(-3 STD) TROUGH OVER THE MISSISSIPPI VALLEY...WILL GENERATE A SUB-
565DM CLOSED LOW OVER THE OHIO VALLEY. THIS DOMINANT BLOCK WILL
REMAIN TO OUR WEST THROUGH THIS PERIOD...SO BEING ON THE `WARM` SIDE
OF THE FEATURE...OUR FORECAST AREA WILL BE GUARANTEED TO EXPERIENCE
ABOVE NORMAL TEMPERATURES. IN FACT...TEMPERATURES ON TUESDAY WILL BE
DOWNRIGHT SUMMER LIKE WITH READINGS MORE TYPICAL OF LATE JULY/EARLY
AUGUST. WHILE THE MERCURY WILL TREND LOWER AFTER THAT POINT...THEY
WILL MOST CERTAINLY REMAIN ABOVE NORMAL THROUGH AT LEAST THURSDAY.
BY THE TIME WE OPEN THIS PERIOD ON TUESDAY...A MID LEVEL
CIRCULATION WILL HAVE ALREADY TAKEN SHAPE OVER MISSOURI. ITS
ATTENDANT SUB-1000MB SFC LOW OVER ILLINOIS WILL LIKELY OCCLUDE BY
THE END OF THE DAY...MARKING THE PEAK STRENGTH OF THE OVERALL
SYSTEM. MEANWHILE DOWNSTREAM..A 40KT SOUTHERLY LOW LEVEL JET WILL
PUMP H85 TEMPS OF +15/16C ACROSS OUR FORECAST AREA. BEING DEEP
WITHIN THE WARM SECTOR OF THE STORM SYSTEM...THIS WILL SEND OUR
AFTERNOON HIGHS TO BETWEEN 75 AND 80...WITH THE VALLEYS AND LAKE
PLAINS WEST OF ROCHESTER LIKELY PUSHING INTO THE LOWER 80S. THE
ANOMALOUSLY STRONG SOUTHERLY FLOW WILL NOT ONLY HELP TO PRODUCE
UNUSUAL WARMTH ACROSS OUR REGION...BUT WILL KEEP PCPN FROM THE
AFOREMENTIONED SYSTEM WELL TO OUR WEST.
THE MATURE...VERTICALLY STACKED SYSTEM WILL BE CENTERED OVER
ILLINOIS TUESDAY NIGHT WHILE AN OCCLUDED SFC FRONTAL BOUNDARY WILL
STRETCH SOUTHWARDS ALONG THE SPINE OF THE APPALACHIANS. A 45-50KT
LOW LEVEL JET AHEAD OF THE SYSTEM WILL CONTINUE TO RETARD THE
EASTWARD PROGRESSION OF THE ASSOCIATED SHOWER ACTIVITY OVER OUR
REGION...SO WILL CONTINUE THE TREND OF SLOWING THE ONSET OF PCPN.
WILL BACK OFF POPS TO CHC FOR THE WESTERN COUNTIES AND SLGT CHC FOR
EASTERN LAKE ONTARIO REGION. WHILE THE STRONG LLJ WILL TEMPORARILY
KEEP THE PCPN TO OUR WEST...IT WILL ADVECT PWAT VALUES OF 1.5 TO
1.75" INTO OUR AREA FOR LATE TUESDAY NIGHT AND WEDNESDAY...SETTING
THE STAGE FOR A POTENTIALLY VERY WET 18 HOUR PERIOD. TUESDAY NIGHT
LOWS WILL GENERALLY RANGE FROM 60 TO 65...WHICH WILL BE SOME 20
DEGREES F ABOVE NORMAL. ANOTHER WAY OF LOOKING AT THE ANOMALOUS
NATURE OF THESE VALUES IS THAT THEY WILL ACTUALLY BE NOTABLY HIGHER
THAN WHAT THE DAYTIME HIGHS SHOULD BE FOR THIS TIME OF YEAR.
ON WEDNESDAY...THE STACKED LOW WILL SLOWLY CROSS THE MID WEST WHILE
THE AXIS OF DEEPEST MOISTURE ASSOCIATED WITH ITS SFC OCCLUDED FRONT
WILL PUSH ACROSS THE WESTERN COUNTIES OF NEW YORK. GIVEN PWAT VALUES
IN THE VCNTY OF 1.75"...LIFT PROVIDED BY A STRONGLY DIVERGENT UPPER
LEVEL FLOW AND 40+KT LOW LEVEL JET JUST AHEAD OF THE OCCLUDED FRONT
SHOULD PRODUCE WIDESPREAD SHOWERS WITH RAINFALL LIKELY REACHING A
HALF TO ONE INCH OVER THE WESTERN COUNTIES. WHILE THE AIRMASS WILL
ONLY BE MARGINALLY UNSTABLE...THE SYNOPTIC FORCING COULD BE ENOUGH
TO TOUCH OFF AN EMBEDDED THUNDERSTORM OR TWO. WILL USE CAT POPS OVER
THE WESTERN COUNTIES AND LIKELY EAST OF LK ONTARIO.
THE CLOSED LOW WILL SLOWLY START TO OPEN UP AS IT MAKES ITS WAY TO
SOUTHERN LOWER MICHIGAN WEDNESDAY NIGHT...WHILE THE SFC OCCLUSION
WILL MAKE ITS WAY ACROSS OUR FINGER LAKES REGION. THIS WILL PLACE
SITES FROM THE FINGER LAKES EAST IN THE PRIME AREA FOR WIDESPREAD
SHOWERS...WITH THE ACTIVITY OVER THE FAR WESTERN COUNTIES TAPERING
OFF DURING THE COURSE OF THE NIGHT AS A DRY SLOT WORKS IN BEHIND THE
OCCLUSION.
THE FILLING UPPER LEVEL STORM SYSTEM WILL PUSH NORTH ACROSS LOWER
MICHIGAN ON THURSDAY...WHILE ITS SUPPORTING LONGWAVE TROUGH WILL
BECOME NEGATIVELY TILTED OVER THE LOWER GREAT LAKES. AT THE SFC...
THE OCCLUSION WILL EXIT THE EASTERN LAKE ONTARIO REGION...BUT NOT
BEFORE PRODUCING A FEW MORE HOURS OF SHOWERS DURING THE MORNING.
WHILE SYNOPTIC MOISTURE WILL ROTATE BACK ACROSS THE LOWER GREAT
LAKES BEHIND THE AFOREMENTIONED DRY SLOT...THERE WILL BE A LACK OF
ANY SIGNIFICANT FORCING MECHANISM TO SUPPORT MUCH IN THE WAY OF
SHOWERS WITHIN THE BASE OF THE UPPER LEVEL TROUGH...SO WILL ONLY USE
CHC POPS FOR THE WESTERN COUNTIES.
THE BASE OF THE NEGATIVELY TILTED LONGWAVE TROUGH WILL PUSH ACROSS
OUR FORECAST AREA THURSDAY EVENING BEFORE EXITING DURING THE
OVERNIGHT HOURS. LOW LEVEL RIDGING AND A GENERAL LACK OF ANY
SIGNIFICANT FORCING SHOULD NOT DO MUCH TO PROMOTE ANY ORGANIZED
SHOWER ACTIVITY...SO WILL BACK OFF ON POPS AND ONLY USE LOW CHC.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
THE WEATHER IS NOT EXPECTED TO BE NEARLY AS ACTIVE DURING THIS
PERIOD...ALTHOUGH WE CAN ANTICIPATE A TREND TOWARDS LOWER...MORE
SEASONABLE TEMPERATURES.
AS ENERGY WITHIN THE EXITING STORM SYSTEM PUSHES NORTH ACROSS QUEBEC
ON FRIDAY...A BROAD LONGWAVE TROUGH WILL BE LEFT ACROSS MUCH OF
EASTERN CANADA AND THE GREAT LAKES. THIS TROUGH WILL BECOME
RE-ENERGIZED (`RELOAD` IF YOU WILL) DURING THE COURSE OF THE DAY AS
A ROBUST SHORTWAVE OVER THE CANADIAN PRAIRIES WILL PUSH SOUTHEAST
ACROSS THE UPPER MISSISSIPPI VALLEY. THIS WILL LEAD TO SOME WEAK
RIDGING OVER THE LOWER GREAT LAKES...ENOUGH TO LIKELY KEEP THE DAY
RAIN FREE. H85 TEMPS ARND 8C WILL SUPPORT AFTERNOON HIGHS IN THE
60S.
THE AFOREMENTIONED SHORTWAVE WILL DIG INTO...AND THEREBY
SHARPEN...THE BASE OF THE LONGWAVE TROUGH OVER THE LOWER GREAT LAKES
LATE FRIDAY NIGHT AND SATURDAY. THIS SHOULD PUSH A COLD FRONT ACROSS
OUR REGION...PRODUCING SOME SCATTERED SHOWERS IN THE PROCESS.
BY SUNDAY...THE TROUGH WILL BE CENTERED OVER THE ST LAWRENCE VALLEY
WITH DEEP COLD ADVECTION OVER OUR REGION SENDING H85 TEMPS TO NEAR
2C. THIS WILL BE COLD ENOUGH TO CREATE SOME LAKE INDUCED INSTABILITY
WITH NUISANCE LAKE EFFECT RAIN SHOWERS EAST OF BOTH LAKES. HIGHS
SUNDAY AFTERNOON SHOULD ONLY BE IN THE LOW TO MID 50S.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
VFR FLIGHT CONDITIONS WILL PREVAIL ACROSS MOST OF THE AREA THROUGH
THE TAF CYCLE...WITH THE EXCEPTION OF THE HIGHER TERRAIN.
WARM ADVECTION WILL INCREASE TODAY WHICH WILL HELP ADVECT LOW LEVEL
MOISTURE NORTHWARD INTO WESTERN AND CENTRAL NY...WITH ABUNDANT CLOUD
COVER CONTINUING THROUGH MUCH OF THE DAY TODAY. CIGS SHOULD BE
PRIMARILY LOW VFR ACROSS THE LOWER ELEVATIONS OF WESTERN NEW YORK AS
SOUTHERLY DOWNSLOPE WINDS INCREASE.
ACROSS THE HIGHER TERRAIN OF THE SOUTHERN TIER EXPECT MVFR CIGS TO
OVERSPREAD THE AREA AND LAST INTO AT LEAST THE FIRST HALF OF
MONDAY...WITH SOME IFR POSSIBLE ACROSS THE HIGHEST ELEVATIONS. LOW
VFR/MVFR CIGS ARE EXPECTED TO MOVE FURTHER NORTH ACROSS THE
KBUF/KIAG/KROC TERMINALS. FINALLY...LOW VFR CIGS WILL REACH KART
BY THIS MORNING. EXPECT MVFR CIGS ACROSS THE HIGHER TERRAIN...WITH
SOME IFR POSSIBLE ACROSS THE HIGHEST ELEVATIONS HERE AS WELL.
A WEAK LOW LEVEL JET WILL CROSS THE REGION THIS MORNING WITH WINDS
INCREASING TO AROUND 30 KNOTS JUST OFF THE DECK. IT APPEARS WIND
SPEEDS WILL NOT BE QUITE HIGH ENOUGH TO PRODUCE TRUE LOW LEVEL WIND
SHEAR.
OUTLOOK...
TUESDAY...MAINLY VFR.
WEDNESDAY...AREAS OF MVFR WITH SHOWERS LIKELY AND A CHANCE OF
THUNDERSTORMS.
THURSDAY...AREAS OF MVFR WITH SHOWERS LIKELY.
FRIDAY...VFR/MVFR WITH A CHANCE OF SHOWERS.
&&
.MARINE...
HIGH PRESSURE WILL DRIFT OFF THE NEW ENGLAND COAST TODAY AS LOW
PRESSURE MOVES SLOWLY FROM THE CENTRAL PLAINS TO THE WESTERN LAKES
BY WEDNESDAY. SOUTHERLY WINDS WILL INCREASE AHEAD OF THE LOW
TODAY...BUT CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY
CRITERIA THROUGH TUESDAY. SOUTHERLY WINDS WILL INCREASE FURTHER ON
TUESDAY NIGHT AND MAY BRING SMALL CRAFT ADVISORY LEVEL WINDS...
ALTHOUGH THE OFFSHORE WIND COMPONENT WILL KEEP THE GREATER WAVE
ACTION IN CANADA.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TMA
NEAR TERM...TMA
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...TMA
MARINE...TMA
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
211 AM EDT MON OCT 13 2014
.SYNOPSIS...
HIGH PRESSURE OVER NEW YORK STATE WILL SLIDE EAST OFF THE NEW
ENGLAND COAST TONIGHT. A SOUTHERLY FLOW OF WARMER AND INCREASINGLY
MOIST AIR WILL OVERSPREAD THE REGION MONDAY AND LAST THROUGH
TUESDAY WITH A CHANCE FOR A FEW LIGHT RAIN SHOWERS. THE SOUTHERLY
WINDS WILL BRING MUCH MILDER WEATHER FOR THE REGION ESPECIALLY BY
TUESDAY AND WEDNESDAY WITH TEMPERATURES EXCEEDING 70 DEGREES IN
MANY LOCATIONS. A COLD FRONT WILL APPROACH THE REGION WEDNESDAY
WITH A CHANCE FOR MORE WIDESPREAD SHOWERS AND EVEN A FEW
THUNDERSTORMS BEFORE TEMPERATURES COOL DOWN LATER THIS WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
830 PM UPDATE...
BLIND SPOTS TO THE SOUTHWEST...AS WE ARE MISSING SOME RADAR DATA FROM
NEIGHBORING OFFICES. HOWEVER IT DOES APPEAR FROM THE MOSAIC
PICTURE THAT THE PRECIPITATION IS HAVING A HARD TIME MOVING NORTH
THROUGH THE COOL/DRY AIR MASS OVER CENTRAL PA. WILL NEED TO MAKE
ADJUSTMENTS TO PRECIP TIMING AND POPS TO BETTER REFLECT THE LATEST
TRENDS AND HRRR GUIDANCE.
3 PM UPDATE...
VISIBLE SATELLITE IMAGERY SHOWS A RARE SIGHT ACROSS CENTRAL NEW
YORK AND NORTHEAST PENNSYLVANIA...COMPLETELY CLEAR SKIES. EVEN
WITH BRIGHT SUNSHINE...MAXIMUM TEMPERATURES STILL WERE A LITTLE
BELOW NORMAL WITH 50S DOMINATE. THE VISIBLE IMAGERY SHOWS A LARGE
LOWER CLOUD SHIELD ACRS SRN OHIO...SW PA AND ACRS VA TO THE
DELMARVA. LATEST RAP AND NAM SHOWS THAT THE 850 MB RH FIELDS
CORRELATE WELL WITH THE NRN EDGE OF THIS CLD SHIELD TO THE S. WITH
A LARGE HIGH PRESSURE SYSTEM THAT IS CURRENTLY OVER NY PROJECTED
TO SLIDE OFF THE NORTHEAST COAST BY 12Z MON...A SOUTHERLY LOW
LEVEL FLOW WILL DEVELOP. THIS SRLY FLOW WILL ADVECT THIS CLD
SHIELD NORTHEASTWARD OVERNIGHT AND EVENTUALLY SPREAD ACRS ALL OF C
NY AND NE PA BTWN ABT MIDNIGHT AND 8 AM MON AS PER LATEST RAP 850
MB RH FIELDS. ADDTNLY...WARM AIR ADVECTION/ISENTROPIC LIFT WILL
BEGIN OVERNIGHT AND LAST THRU MONDAY. BUT THIS OCCURS AS THE UPPER
LEVEL HGTS RISE INDICATING THAT THE ISENTROPES ARE DESCENDING WITH
THE WAA. THUS SOME OF THE ISEN LIFT WILL BE CANCELLED LATE TONIGHT
THRU MONDAY. HENCE WE DON/T SEE A LOT OF PRECIP. AFTER
COLLABORATION WITH NEIGHBORING WFO`S DECIDED ON SLGHT TO CHC POPS
WITH THIS FIRST WAA WAVE THRU MON PM. HENCE INTRODUCE SLGHT CHC TO
CHC POPS BEGINNING LATE TONIGHT AND CONTINUING THRU MONDAY FOR
-SHRA. TEMPERATURES WILL BE ON THE REBOUND WITH MAXES REACHING
WELL INTO THE 60S...AND POSSIBLY 70F IN THE UPPER FINGER LAKES.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
FIRST WAA/ISEN LIFT SURGE PASSES BY MON PM WITH A FEW SHRA. THEN
OVERNIGHT MON TO TUE...ALL 4 SYNOPTIC SCALE MODELS INDICATE
INCREASING LL MOISTURE AND A SRLY FLOW AND WHAT LOOKS LIKE
DRIZZLE OR JUST A FEW LIGHT SHRA IN THE UPSLOPE REGIONS OF NE PA
AND SC NY/CATSKILLS. THUS HAVE SLGHT CHC-CHC POPS IN THESE AREAS
AND NO POPS FARTHER N TO THE LAKE ONTARIO PLAIN TO UPPER MOHAWK
VALLEY.
FOR TUESDAY NIGHT...SRLY FLOW INCREASES AREA WIDE WITH INCREASING MOISTURE
TRANSPORT INTO NY AND PA. THERE ARE UNCERTAINTIES AS TO THE TIMING
OF THE ARRIVAL OF THE MAIN FRNTL BAND OF SHRA WITH THE PROGRESSION
OF THE UPPER LEVEL LOW EASTWARD. ALL SYNOPTIC MODELS INDICATE THAT
THE UPPER LEVEL LOW REACHES THE WRN OHIO VALLEY 12Z WED. BUT THE
STRGEST PRESSURE GRADIENT AND ASSCTD LL FLOW AND MOISTURE
TRANSPORT VARIES IN PLACEMENT DEPENDING ON MODEL. THE CMC IS
FASTEST WITH PLENTY OF MOISTURE OVER NY AND PA BY 12Z WED. THE
EURO IS THE SLOWEST WITH HARDLY ANY PRECIP OR MOISTURE REACHING
NE PA OR C NY BY 12Z WED. THE GFS AND NAM ARE IN BTWN. SO I HAVE
BROADENED POPS ACRS CWA TUE NGT TO ACCOUNT FOR THE UNCERTAINTIES
AND LEAVE THEM IN THE SLGHT CHC TO CHC RANGE.
FOR WEDNESDAY...MODELS AGAIN VARY ON HOW QUICKLY THE UPPER LEVEL
LOW MOVES TO THE EAST BUT ALL INDICATE PRECIP OVER NY AND PA SO
HAVE LIKELY POPS...ESP BY WED AFTERNOON. GFS AND NAM INDICATE SOME
INSTABILITY AS WELL AS COLDER AIR MOVES IN ALOFT ABV THE WARM AND
FAIRLY MOIST AIR MASS IN PLACE. SO WE CONTINUE MENTION OF SOME
TSRA FOR WED IN GRIDS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
315 PM EDT UPDATE...
FOLLOWED CLOSELY TO WPC GUIDANCE AND MADE MINOR ADJUSTMENTS TO THE
PREVIOUS FORECAST. THE EXTENDED FORECAST PERIOD CONTINUES TO LOOK
UNSETTLED. THE PORTENT UPPR LVL LOW THAT IS STARTING TO DIG SOUTH
ALONG THE EASTERN SIDE OF THE ROCKIES WILL CONTINUE TO DIG SOUTH
AND AMPLIFY THROUGH MONDAY MORNING. THE LOW WILL SLOWLY MOVE EAST
AND BECOME CLOSED IN NATURE BY TUESDAY EVENING. THIS LOW WILL BE
THE CULPRIT FOR THE CHANCE FOR RAIN SHOWERS THROUGH FRIDAY.
ANOTHER SHORTWAVE TROUGH WILL SWING INTO THE REGION IN ITS WAKE
SATURDAY MORNING RESULTING IN THE CHANCE FOR ADDITIONAL SHOWERS
THROUGH THE WEEKEND. THUS KEEP AT LEAST CHANCE FOR SHOWERS THROUGH
THE WHOLE PERIOD.
TEMPS DURING THIS TIME FRAME WILL BE AT OR ABOVE THE SEASONAL
NORM.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
A SOUTHERLY FLOW OF AIR WILL BRING MVFR CIGS TO MOST TERMINALS
THIS MORNING OUTSIDE OF KSYR. CIGS WILL GENERALLY BE 2KT OR
GREATER, BUT SOME LOW END MVFR CIGS POSSIBLE AT THE ELEVATED SITES
OF KITH AND KBGM.
MVFR CIGS ARE EXPECTED TO PERSIST THROUGH AT LEAST MID MORNING.
AFTER THAT TIME SOME QUESTION DOES EXIST IN TERMS OF WHETHER OR
NOT THIS DECK WILL RAISE TO VFR OR NOT. MODEL GUIDANCE WOULD
SUGGEST MVFR CIGS ALL DAY. GIVEN GOOD MODEL CONSISTENCY I WENT
WITH A MORE PESSIMISTIC SOLUTION OF ALL DAY MVFR CIGS. SOME MODEL
SOUNDINGS DO SUGGEST WE MAY SEE A BRIEF PERIOD OF VFR THIS
AFTERNOON. WITH THE AFTERNOON PERIOD BEING A CLIMATOLOGICALLY
FAVORED TIME FOR VFR I INCLUDED A TEMPO GROUP TO SHOW A CHANCE
AT SOME SLIGHT IMPROVEMENT. WHATEVER HAPPENS THIS AFTERNOON, ALL
GUIDANCE POINTS TO LOWERING CIGS AGAIN TONIGHT. MVFR CIGS ARE
LIKELY OUTSIDE OF KSYR, WITH A REAL SHOT AT IFR CIGS ESPECIALLY ON
THE HILLTOP SITES.
SOUTH TO SOUTHEAST WINDS 5 KTS THIS MORNING INCREASING TO AROUND
10 KTS BY LATE MORNING. SOUTH TO SOUTHEAST WINDS TONIGHT 5 TO 10
KTS.
OUTLOOK...
TUE...DEEP SRLY FLOW AHEAD OF CNTRL U.S. TROF...RESULTING IN
PERIODIC RESTRICTIONS DUE TO CIGS/SHRA/BR.
TUE NGT TO THURS...STEADY RAIN...RESULTING IN MVFR...AND POSSIBLY
IFR CONDITIONS.
FRIDAY...RESTRICTIONS POSSIBLE IN LIGHT RAIN SHOWERS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN/DJP
SHORT TERM...DJN
LONG TERM...KAH
AVIATION...HEDEN
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1150 PM CDT SUN OCT 12 2014
.UPDATE...
ISSUED AT 1144 PM CDT SUN OCT 12 2014
RAIN AREA IS MOVING EAST BUT OVERALL INTENSITY IS DIMINISHING.
USING RAP/HRRR/NAM12 BACKEDGE OF THE RAIN INTO GRAND FORKS NR
09Z...FARGO BY 11Z AND BEMIDJI 15Z OR SO. VFR STRATOCU DECK CLEARS
OUT FARILY QUICK BEHIND THE RAIN LEAVING CIRRUS BEHIND IT. TRUE
CLEARING BOTTNEAU-GARRISON MOVING EAST. RAP 300 MB RH SHOWS HIGH
CLOUD CLEARING INTO THE RRV MID-LATE MORNING MONDAY. SOME CONCERN
WITH FOG BUT UNCERTAIN IF LIGHT OR WIDESPREAD LOWER VSBYS.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 245 PM CDT SUN OCT 12 2014
MAIN CHALLENGE FOR THE SHORT TERM FORECAST WILL BE PCPN CHANCES
TONIGHT/EARLY MONDAY AND THEN DEGREE OF WARMUP INTO MID WEEK. AS
OF MID AFTERNOON ECHOES WERE DEVELOPING A LITTLE BIT MORE ACROSS
THE SW FA BUT OVERALL NOT TOO IMPRESSIVE YET. STILL SEEING SUN
ACROSS THE FAR EASTERN FA WHERE TEMPS HAD RISEN INTO THE LOW 60S.
MORE CLOUDS ACROSS THE WEST WITH TEMPS IN THE MID TO UPPER 50S.
MODELS STILL GOING BACK AND FORTH WITH WHERE THE MAIN RAIN BAND
WILL SET UP TONIGHT BUT THE OVERALL TREND IS FOR LESS PCPN AND A
WEAKER SYSTEM. THINK THE BAND WILL INITIALLY SET UP ALONG A KJMS
TO KGFK TO KROX LINE AND SLOWLY SHIFT MORE TO A KFAR TO KBDE LINE
THRU THE EVENING. BY MIDNIGHT IT SHOULD SHIFT MORE INTO THE MN
SIDE OF THE FA. CLEARING TRENDS ON THE BACK SIDE OF THE SYSTEM
WORKING INTO THE KDVL REGION LATE WILL HAVE TO BE WATCHED. IF
CLEARING MOVES IN SOONER AND WINDS STAY ON THE LIGHT SIDE TEMPS
MAY DROP MORE THAN EXPECTED. LEFT SOME LINGERING PCPN CHANCES ON
THE MN SIDE OF THE FA ON MONDAY MORNING BUT PCPN MAY SLIP OFF TO
THE EAST QUICKER. LOOKING AT A PRETTY NICE DAY OVERALL MONDAY WITH
QUITE A BIT OF SUN AND TEMPS SIMILAR OR A LITTLE WARMER THAN
TODAY. LIGHT WINDS/CLEAR SKIES CONTINUE INTO MON NIGHT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 245 PM CDT SUN OCT 12 2014
RETURN SOUTH FLOW GETS GOING ON TUE AS 850MB TEMPS RISE TO 6C TO
8C ACROSS THE FA. FLOW STILL PRETTY WEAK THROUGH MOST OF THE DAY
AND WITH THE COOL START WILL KEEP TUE HIGHS SIMILAR TO MONDAYS.
850MB TEMPS RISE TO A GOOD 16C OR SO BY 00Z THU WITH GUSTY SOUTH
WINDS. STILL NOT A FAVORABLE DIRECTION FOR REALLY GOOD WARMING BUT
DID RAISE TEMPS A LITTLE MORE FROM WHAT THEY WERE.
FOR THE WED NIGHT THROUGH SUNDAY TIME FRAME...TEMPS WILL START
OUT WELL ABOVE NORMAL AND COOL BELOW NORMAL BY NEXT FRIDAY. IT
SHOULD BE MAINLY DRY THROUGH THE PERIOD...WITH SOME LOWER CHANCES
FOR RAIN SHOWERS THU NIGHT INTO FRI...PERHAPS MIXING WITH SOME
LIGHT SNOW BY FRI NIGHT IN THE NORTHEAST FA. THERE ARE NO BIG
STORMS ON THE HORIZON THOUGH...WITH THE RELATIVELY QUIET WEATHER
PATTERN CONTINUING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1144 PM CDT SUN OCT 12 2014
AS RAIN ENDS IN THE RED RIVER VALLEY AND SKIES CLEAR SOMEWHAT
OVERNIGHT-MONDAY MORNING COULD SEE A PERIOD OF FOG AND MVFR
CLOUDS. VERY UNCERTAIN OF COVERAGE OF THIS BUT PUT SOME IDEAS OF
THIS IN THE 06Z TAFS FOR TVF/GFK/FAR. RAIN ENDS IN BEMIDJI BY MID
MORNING. LIGHT WINDS TURNING NORTHWEST 10-15 KTS MONDAY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...RIDDLE
SHORT TERM...GODON
LONG TERM...GODON/DK
AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1002 AM EDT MON OCT 13 2014
.SYNOPSIS...
HIGH PRESSURE CENTERED OFF THE SOUTHEAST NEW ENGLAND COAST WILL
CONTINUE TO MOVE SLOWLY OUT TO SEA THROUGH TONIGHT AND TUESDAY. A
COLD FRONT IS FORECAST TO APPROACH FROM THE WEST ON WEDNESDAY, AND
IT SHOULD PASS THROUGH OUR REGION ON THURSDAY. HIGH PRESSURE IS
EXPECTED TO NOSE INTO OUR AREA FROM THE SOUTHWEST FOR FRIDAY.
ANOTHER COLD FRONT FROM THE NORTHWEST IS ANTICIPATED TO ARRIVE
OVER THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WITH THE MID MORNING UPDATE, WE INCREASED POPS ACROSS OUR DELMARVA
ZONES TO REFLECT THE SCATTERED SHOWERS EXPECTED OVER THE NEXT FEW
HOURS. THIS IS NOT ONLY SUPPORTED BY CURRENT RADAR DATA, BUT THIS
IS ALSO THE AREA WHERE THE RAP AND THE HRRR MOST HINT AT
MEASURABLE PRECIP FOR OUR REGION THROUGH EARLY AFTERNOON. MOST
LOCATIONS WILL RECEIVE A COUPLE OF HUNDREDTHS TO AROUND A TENTH OF
AN INCH OF PRECIP. IN ADDITION, WE BACKED OFF ON THE POSSIBILITY
FOR ISOLATED SHOWERS FOR OUR FAR NORTHWEST ZONES FOR THE NEXT FEW
HOURS AND INSTEAD WENT WITH SPRINKLES AS BOTH RADAR AND MODEL DATA
INDICATE LITTLE IF ANY MEASURABLE PRECIP THROUGH MIDDAY. OVERCAST
SKIES WILL CONTINUE FOR THE ENTIRE FORECAST AREA THROUGH THE DAY,
AND NO CHANGES WERE NEEDED TO MAX TEMPERATURES AT THIS TIME. WE
DID TWEAK HOURLY TEMPS AND DEWPOINTS USING THE LAV/LAMP GUIDANCE
THROUGH THE EARLY AFTERNOON.
OTHERWISE, HIGH PRESSURE AT THE SURFACE WILL REMAIN OFFSHORE OF
THE NORTHEAST STATES THROUGH TODAY, WHICH WILL KEEP A SOUTH-
SOUTHEAST FLOW ACROSS THE AREA. THIS SOUTHERLY FLOW WILL KEEP THE
LOW LEVELS MOIST, LEADING TO OVERCAST SKIES THROUGH THE DAY. THERE
IS SOME VERY WEAK LIFT MOVING THROUGH DURING THE DAY AS SOME WEAK
VORTICITY SLIDES INTO THE AREA, SO THERE COULD BE SOME ISOLATED-
SCATTERED SHOWERS THROUGH THE DAY. QPF AMOUNTS ARE LIGHT, SO ANY
RAIN SHOULD ONLY AMOUNT TO A COUPLE OF HUNDREDTHS OF AN INCH OVERALL.
WE DO NOT EXPECT MUCH IN THE WAY OF SUNSHINE TODAY, SO WE DO NOT
EXPECT A SIGNIFICANT WARMING TODAY. A BLEND OF MET/MAV MOS AND
MOSGUIDE WAS USED, WITH SLIGHTLY HIGHER EMPHASIS ON THE COOLER
MET.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
THE HIGH PRESSURE DOES NOT MOVE MUCH THROUGH TONIGHT, REMAINING
OFFSHORE OF THE NORTHEAST. THIS WILL KEEP CLOUDY SKIES AND PLENTY
OF LOW-LEVEL MOISTURE FLOWING ACROSS THE AREA. THERE WILL REMAIN A
CHANCE OF RAIN OVERNIGHT AS ANOTHER WEAK PIECE OF VORTICITY SLIDES
ACROSS THE AREA. QPF AMOUNTS REMAIN LIGHT, SO ANY RAIN SHOULD ONLY
AMOUNT TO A COUPLE OF HUNDREDTHS OF AN INCH. WITH THE AMOUNT OF
LOW-LEVEL MOISTURE, IT`S ALSO POSSIBLE WE MAY ALSO SEE SOME PATCHY
DRIZZLE OR FOG DEVELOP AFTER MIDNIGHT, ESPECIALLY FOR THE
NORTHWESTERN HALF OF THE AREA.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
A MID LEVEL RIDGE IS FORECAST TO BE LOCATED OVER THE WESTERN
NORTH ATLANTIC ON TUESDAY WITH A CUT OFF LOW CENTERED OVER THE
SAINT LOUIS VICINITY. THE LOW IS EXPECTED TO DRIFT OVER INDIANA
FOR WEDNESDAY.
WE EXPECT OUR REGION TO GET INTO THE WARM SECTOR AHEAD OF THE
SYSTEM APPROACHING FROM THE WEST FOR TUESDAY INTO WEDNESDAY.
TEMPERATURES SHOULD RISE NEAR OR A BIT ABOVE 80 DEGREES IN MUCH OF
OUR REGION DURING THE AFTERNOON HOURS ON BOTH DAYS IN THE
SOUTHEAST TO SOUTH SURFACE FLOW.
THERE IS A LOW OR SLIGHT CHANCE OF SHOWERS IN THE UPSLOPE AREAS
OF EASTERN PENNSYLVANIA ON TUESDAY AND TUESDAY NIGHT. ALSO, THE
INCREASING LOW LEVEL MOISTURE THROUGHOUT OUR REGION MAY RESULT IN
PATCHY LOW CLOUDS AND FOG FOR LATE TUESDAY NIGHT AND EARLY
WEDNESDAY MORNING.
THE MAIN AREA OF PRECIPITATION APPROACHING FROM THE WEST IS
ANTICIPATED TO MAKE SLOW PROGRESS INTO OUR REGION ON WEDNESDAY.
THE MID LEVEL LOW IS FORECAST TO LIFT OVER MICHIGAN AND LAKES
HURON AND SUPERIOR DURING THURSDAY AND THURSDAY NIGHT. THE LOW IS
EXPECTED TO PULL A NEGATIVE TILT TROUGH OVER OUR REGION ON
THURSDAY NIGHT.
WE ARE FORECASTING AN INCREASING CHANCE FOR SHOWERS ON WEDNESDAY
NIGHT WITH OUR MOST LIKELY TIME FOR PRECIPITATION BEING FROM LATE
WEDNESDAY NIGHT INTO THURSDAY. SHOWERS ARE ANTICIPATED TO LINGER
INTO THURSDAY NIGHT UNTIL THE MID LEVEL TROUGH AXIS CLEARS OUR
REGION.
WE WILL CONTINUE TO MENTION THE POTENTIAL FOR THUNDERSTORMS FOR
WEDNESDAY NIGHT INTO THURSDAY WITH THIS ROBUST SYSTEM. CONDITIONS
ARE ANTICIPATED TO BE AT LEAST MARGINALLY UNSTABLE WITH SURFACE
DEW POINTS GENERALLY IN THE LOWER AND MIDDLE 60S. ANY CONVECTION
SHOULD BE RELATIVELY LOW TOPPED. HOWEVER, ENOUGH SHEAR IS EXPECTED
TO BE PRESENT TO RESULT IN SOME ORGANIZED STORMS WITH STRONG WIND
GUSTS POSSIBLE. PRECIPITABLE WATER VALUES MAY GET UP INTO THE 1.8
INCH RANGE AND THERE COULD BE A PERIOD OF MODERATE TO HEAVY
RAINFALL.
SOME DRYING IS EXPECTED TO FOLLOW IN THE SOUTHWEST FLOW IN THE
WAKE OF THE COLD FRONT FOR FRIDAY. TEMPERATURES SHOULD BEGIN TO
DROP BACK TOWARD NEAR NORMAL LEVELS FOR MID OCTOBER.
A LONG WAVE MID LEVEL TROUGH IS ANTICIPATED TO SETTLE OVER THE
EASTERN STATES FOR NEXT WEEKEND ALONG WITH THE ARRIVAL OF AN
ASSOCIATED SURFACE COLD FRONT. THE BOUNDARY IS NOT EXPECTED TO
HAVE MUCH MOISTURE ASSOCIATED WITH IT.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
REST OF TODAY...VFR TO MVFR CEILINGS OVERALL. THERE IS A CHANCE THAT
ANY MVFR CEILINGS IMPROVE TO VFR FOR A TIME THIS AFTERNOON. A FEW
SPRINKLES OR SHOWERS WILL BE AROUND ESPECIALLY FROM ABOUT KPHL ON
SOUTHWARD, HOWEVER ISOLATED TO SCATTERED COVERAGE AND THEREFORE NOT
INCLUDED IN THE TAFS AT THIS TIME. LIGHT AND VARIABLE WINDS,
BECOMING SOUTH-SOUTHEAST 5-8 KNOTS.
TONIGHT...MVFR CEILINGS SHOULD LOWER TO AREAS OF IFR. WHILE THERE
COULD BE A FEW SHOWERS, SOME DRIZZLE MAY DEVELOP ESPECIALLY NORTH
AND WEST OF KPHL. AS THE MOISTURE INCREASES, SOME FOG SHOULD DEVELOP
WITH THE POTENTIAL FOR VISIBILITIES TO LOWER TO IFR. SOUTH-SOUTHEAST
WINDS AROUND 5 KNOTS, BECOMING LIGHT AND VARIABLE AT MANY TERMINALS.
OUTLOOK...
TUESDAY MORNING...CONDITIONS VARYING BETWEEN MVFR AND VFR. LOW
CLOUDS AND FOG ARE POSSIBLE AND CONDITIONS MAY DROP INTO THE IFR
RANGE FOR A TIME. A CHANCE OF SHOWERS, MAINLY AROUND KRDG AND
KABE.
TUESDAY AFTERNOON AND TUESDAY EVENING...MAINLY VFR.
LATE TUESDAY NIGHT AND WEDNESDAY MORNING...CONDITIONS VARYING
BETWEEN MVFR AND VFR. LOW CLOUDS AND FOG MAY RESULT IN AREAS OF
IFR. A CHANCE OF SHOWERS, MAINLY AROUND KRDG AND KABE.
WEDNESDAY AFTERNOON...MAINLY VFR WITH A CHANCE OF SHOWERS.
WEDNESDAY NIGHT AND THURSDAY...CONDITIONS VARYING BETWEEN MVFR
AND VFR IN SHOWERS AND SCATTERED THUNDERSTORMS. THE RAIN MAY
BECOME HEAVY. IFR CONDITIONS ARE POSSIBLE AT TIMES.
THURSDAY NIGHT...A CHANCE OF SHOWERS WITH CONDITIONS FORECAST TO
IMPROVE TO ALL VFR.
FRIDAY...MAINLY VFR.
&&
.MARINE...
SUB-SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED TO CONTINUE
ACROSS THE WATERS THROUGH TONIGHT, ALTHOUGH WINDS MAY GUST AROUND
20 KNOTS LATER TODAY THROUGH TONIGHT. SEAS ARE EXPECTED TO REMAIN
AROUND 3-4 FEET THROUGH THE PERIOD.
OUTLOOK...
TUESDAY MORNING...NO MARINE HEADLINES ARE ANTICIPATED.
TUESDAY AFTERNOON THROUGH FRIDAY...A SMALL CRAFT ADVISORY MAY
BECOME NECESSARY ON OUR OCEAN WATERS WITH WAVES EXPECTED TO BUILD
TO 5 TO 7 FEET IN A PERSISTENT SOUTHEAST TO SOUTH FLOW. ALSO, WIND
GUSTS MAY APPROACH 25 KNOTS FROM WEDNESDAY AFTERNOON INTO
THURSDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...IOVINO
NEAR TERM...KLINE/ROBERTSON
SHORT TERM...ROBERTSON
LONG TERM...IOVINO
AVIATION...GORSE/IOVINO
MARINE...IOVINO/ROBERTSON
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1024 AM CDT Mon Oct 13 2014
.UPDATE...
ISSUED AT 1023 AM CDT MON OCT 13 2014
Leading warm front/boundary is steadily lifting northward across
the forecast area, extending roughly along a Quincy to Rantoul
line at 10 am. Visibilities have been steadily improving as the
front moves north, with only isolated areas below 2 miles left.
The big question remains with the potential for severe weather.
Line of storms currently in southeast Missouri extends all the way
into eastern Texas. 0-6km bulk shear already in the 50-60 knot
range along the Illinois/Missouri border and the RAP model shifts
this into central Illinois over the next few hours. Very little
sunshine if any to fuel the fire, with MUCAPE`s only rising into
the 500-1000 J/kg range, but the overall dynamics may be enough to
overcome this limitation. High-res models all agree in a narrow,
fast moving squall line, but have a spread of 2-6 hours in terms
of when the line actually moves through. Latest HRRR brings it as
early as 3 pm around Springfield, ranging to 6 pm with the NSSL
ARW and 8 pm with the 1km NAM nest. The northward movement of the
cells in Missouri would lead some credence to the earlier
solutions.
Have made some timing adjustments to the PoP`s in the grids
through tonight, and also added some mention of severe storms
across the south half of the area late afternoon/early evening.
Temperature trends currently on track.
&&
.SHORT TERM...(Today)
ISSUED AT 342 AM CDT MON OCT 13 2014
High pressure ridge over both east and west coast with a deepening
and slow-moving trof dominating the Plains, moving into the
Midwest. Deepening surface low providing today`s storm system for
the region. Models pretty consistent in depicting this storm in
two main sections...with the frontal convection to the south and the
deformation zone wrapping around the NW side of the low just to
the north. Some issues with the forecast surrounding the placement
of pops to cover the trends with some uncertainty around the
timing and the depth of the dry slot. NAM and GFS all becoming
more pronounced with the dry air in the last run...and the ECMWF
coming into line as well. NSSL WRF even more aggressive with the
dry wedge...also far more showery with regards to the activity
into tonight. Under a slight risk for severe storms today, the
better shear profile to the south with the moderate risk in the
southern tip of the state and western KY...combined with a better
chance for temperature recovery from any showers over the area
this morning. This far north will be tough to scour out the
clouds, though any clearing should be watched closely for
re-energizing ahead of the system... priming for severe weather
activity.
&&
.LONG TERM...(Tonight through Sunday)
ISSUED AT 342 AM CDT MON OCT 13 2014
Models have been very consistent in the last few runs with dropping
the wave into the region and cutting off the 500mb low, parking it
over the region through midweek. Tonight, the storm remains overhead
before wrapping up on itself. Threat for the stronger convection
shifts to the east before midnight... then the pops starting to
lessen with the impact of the dry slot building north into the
state. Exact location of the dry slot adding in some
uncertainty...though the precip after midnight, particularly to the
north and northwest may be dominated with mostly drizzle, but fairly
consistent enough to keep wet and plenty of low clouds through the
early morning hours.
Next couple of days will improve only slightly as the upper low
grows mostly stagnant over the region. Deformation zone starts to
lose structure as the low wraps up on Tuesday and convection from
the front races out ahead of the actual low. Cloudy, gray, showery
and cool conditions continue through Wednesday night under the
persistent cyclonic flow....likely to be dominated by rain without
thunder. Drying out on Thursday as the low finally gets kicked to
the east by another wave diving into the Great Lakes region. ECMWF
pushing a quick short wave into the region late Sun and into
Mon...GFS is dry, so the blend is starting to put some pops into the
forecast. Tempering them for now to low chance with the nature of a
fast short wave in NWrly flow on day 7/8...not a big concern at this
point.
&&
.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
ISSUED AT 540 AM CDT MON OCT 13 2014
LIFR and IFR conditions are expected to continue across all of our
TAF sites thru the period. A warm front was located over southern
Illinois early this morning and is expected to track north of our
area by this afternoon. Along the frontal boundary, scattered
showers and thunderstorms are expected to track north-northeast
this morning with the front and affect all of the TAF locations
before a break in the rain by early this afternoon. North of the
warm front, we have seen areas of dense fog most of the night but
that is expected to gradually lift later this morning as the warm
front shifts to our north.
Our attention will then turn to a squall line that is forecast to
push rapidly northeast out of eastern Missouri this afternoon and
affect areas along and east of I-55. A few of the storms along the
line may be capable of producing strong winds and torrential
rainfall for a short period of time. Current indications suggest
the best timing for this squall line appears to be in the 21z-03z
time frame from southwest to northeast. Once the storms move out,
expect scattered showers from time to time overnight with a
continuation of the low cigs and vsbsy. Surface winds will be
southeast today and increase to between 15 and 25 kts with some
higher gusts possible into this evening before diminishing after
02z from a southeast direction.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Geelhart
SHORT TERM...HJS
LONG TERM...HJS
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS PADUCAH KY
651 AM CDT Mon Oct 13 2014
.UPDATE...
Issued at 651 AM CDT MON OCT 13 2014
The AVIATION section has been updated for the 12Z TAF issuance.
&&
.SHORT TERM...(Today through Wednesday)
Issued at 350 AM CDT MON OCT 13 2014
Decided not to issue a Flash Flood Watch at this time. The latest
HRRR has the main line into Carter and Ripley counties around 18Z
and to the Mississippi River by 21Z this afternoon. Looking at
current radar mosaics, it appears that the latest HRRR may even be
a bit slow. Anyway, followed it fairly closely in timing the main
band through the area in the PoP grids. This is a bit faster than
the previous forecast.
The main convective band may hang up a bit tonight over the
Pennyrile and southwest Indiana, and that is where the heaviest
rain is likely to fall. Using the latest HPC QPF gives that region
2.5"-3" through tonight, which is below 3 hour FFG. Certainly
could see some nuisance issues, but nothing widespread or
significant is expected based on the QPF and FFG. If the FFG is
lowered after this morning`s rains are processed, then the day
shift can re-evaluate.
The 00Z models and the latest HRRR indicate that some scattered
convection will be possible over much of the area through midday,
but then it should dry out, as the main convective band begins to
move through the region. Still cannot rule out a strong storm
through midday, if they become surface-based late this morning.
Damaging winds and hail would be the primary concern.
Wind fields will increase significantly later this afternoon,
presumably with the main band. However, as the line is pushed
faster to the east, there is some concern that it may outrun the
strongest wind fields. Either way there will be plenty of 0-3km
helicity to support rotating updrafts and the 0-1km shear will be
quite strong. The bottom line is that damaging winds and some
tornadoes will be possible. If a supercell can get going just
ahead of the line or persist within the line, a more significant
damaging wind and tornado threat can be expected.
As for timing, figure that the main line will enter Ripley and
Carter counties near 18Z, and push east of the area just after
06Z. That would result in a 12 hour window for severe weather and
heavy rainfall.
Will have to keep good chance PoPs going throughout the region
Tuesday through Wednesday due to the proximity of the upper low,
and the presence of a weak surface trough. The best coverage of
showers is expected Wednesday as the upper low moves right
overhead.
.LONG TERM...(Wednesday through Sunday)
Issued at 350 AM CDT MON OCT 13 2014
The GFS continues to slow down the departure of the pesky upper
level low that will be with us for most of the early part of this
week. Yesterdays 00Z GFS run indicated that the low would be exiting
on Wednesday and now, todays 00Z run indicates that it will be more
like Wednesday night. The 00Z ECMWF is now very similar to the 00Z
GFS. Therefore, chances for showers will continue Wednesday
night/Thursday but chances will be greatest in the east/northeast.
After this system pulls out of the area, a weak/dry front moves
through the area on Friday, followed by high pressure that will keep
us dry through Sunday. Another system may bring us a chance for more
precipitation on Sunday night, but confidence is not high yet so
will keep chances low.
After one more day in the 60s on Thursday, we should finally see
readings into the 70s on Friday, but cool off a bit on Saturday and
Sunday behind the weak cold front.
&&
.AVIATION...
Issued at 651 AM CDT MON OCT 13 2014
Low VFR or MVFR ceilings will develop throughout the region
quickly this morning and persist well into the afternoon. Some
scattered showers or even a brief thunderstorm may impact KCGI
through midday. The main concern for this forecast is timing a
line of thunderstorms through each of the TAF sites. The line is
likely to arrive faster than previously expected. It should reach
KCGI by 20Z, and then push eastward, reaching KOWB by 01Z. A
period of gusty winds up to 40kts can be expected along with IFR
conditions, which may last up to 3 hours in the west and 4 hours
in the east, where the line is expected to slow down. Very gusty
southeast winds will be the rule until the line has passed. IFR
ceilings are a good bet behind the line.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
UPDATE...DRS
SHORT TERM...DRS
LONG TERM...CW
AVIATION...DRS
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
942 AM EDT MON OCT 13 2014
.SYNOPSIS...
HIGH PRESSURE WILL DRIFT EAST FROM LONG ISLAND THROUGH TUESDAY. A
POWERFUL COLD FRONT WILL APPROACH THE AREA FROM THE WEST WEDNESDAY
INTO THURSDAY BEFORE PASSING THROUGH LATE THURSDAY. AN UPPER-LEVEL
LOW WILL PERSIST OVER THE EASTERN STATES THROUGH THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SFC HIPRES OVER NEW ENGLAND HAS WEDGED SWWD DOWN THE MID ATLC
COAST. A CURVY WMFNT EXTENDS EWD FM A MATURE CYCLONE IN THE CENTER
OF THE CONUS. BASED ON DEWPTS...THIS WMFNT HAS PUSHED N OF THE MID
OHVLY INTO IL/IN/OH...BUT THEN DIPS SWD INTO THE CAROLINAS. WHILE
THE MRNG LWX RAOB WAS SATD/STBL...THERES ENUF LIFT OVERRUNNING THE
WMFNT TO PROMOTE SHRA PUSHING ACRS CWFA. THIS ACTIVITY MAINLY S OF
THE PTMC RIVER BUT STRETCHES ACRS SRN MD AS WELL. WHILE QPF LGT...
HV UPDTD FCSTS FOR HIER POPS.
RECENT HRRR RUNS INITIALIZED MRNG PCPN FAIRLY WELL...AND PUSHES E
OF THE METROS BY MIDDAY. THAT WL LEAVE THE MID-LT AFTN HRS
RELATIVELY RAIN-FREE. HV SIDED FCST TWD THIS SOLN...BUT HVNT
TRIMMED POPS ENTIRELY IN RECOGNITION OF ISENT LIFT AND AVBL MSTR.
MAXT WL BE A BIT OF A CHALLENGE...AS WE/LL NEED TO DRY OUT FIRST.
IF THERE WERE ANY SORT OF DIURNAL WARMING...SNDG CUD SUPPORT MAXT
ABV 70F...AS GFS IMPLIES. LAMP OFFERING THIS SOLN AS WELL. HAVING
DOUBTS WHETHER THIS WL HPPN THO. WE/L NED TO GET RID OF LLVL MSTR
FIRST. IF WE DO RISE...ITLL BE FOR A VERY SHORT PD PRIOR TO SUNSET.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
HIGH PRESSURE REMAINS OFF THE COAST TONIGHT THROUGH TUESDAY NIGHT.
BOUNDARY WILL ATTEMPT TO COME BACK NORTH AS A WARM FRONT. THIS WON/T
HAPPEN TONIGHT...POSSIBLY LATER TUESDAY AFTERNOON OR TUESDAY NIGHT
BUT MODELS SOMETIMES TRY TO BRING THESE TOO FAR TO THE NORTH TOO
SOON.
LOTS OF MOISTURE WILL BE AROUND DURING THIS PERIOD FOR CLOUDY SKIES.
LEANED TOWARD SREFS FOR POPS TONIGHT/TUESDAY...FOCUSED CLOSE TO AND
WEST OF THE BLUE RIDGE GIVEN OROGRAPHIC LIFT. SOME GUIDANCE IS
SUGGESTING LOW VIS IN FOG AS WELL. THIS MAY BE MORE OF A STRATUS
THAN FOG SITUATION BUT CERTAINLY CAN/T RULE OUT PATCHY FOG OVERNIGHT
INTO EARLY TUESDAY. START TO BRING POPS FURTHER EAST TUESDAY NIGHT
AS LIFT STARTS TO INCREASE GIVEN UPSTREAM LOW/TROUGH AND OCCLUDED
FRONT.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
THE FOCUS OF THE LONG TERM FORECAST WILL BE WEDNESDAY INTO
THURSDAY. CONTINUED TO SIDE TOWARD THE EURO WITH A SLOWER TRACK OF
THE UPPER LOW AND FRONT.
SLOW MOVING UPPER CUTOFF LOW WILL APPROACH FROM THE WEST WEDNESDAY
INTO THURSDAY WHILE HIGH PRESSURE REMAINS OFF THE EASTERN
SEABOARD. THIS PATTERN FAVORS HIGHER PWATS WITH ABUNDANT MOISTURE
STREAMING NORTHWARD INTO THE FORECAST AREA. GIVEN THE UPPER
DIFFLUENCE AND JET DYNAMICS...EXPECTING HEAVY SHOWERS TO
DEVELOP ALONG WITH A FEW THUNDERSTORMS. TRAINING OF SHOWERS/STORMS
COULD DEVELOP WITH HEAVY RAINFALL AND FLOODING A POSSIBILITY. IN
ADDITION...STRONG LOW LEVEL 925MB FLOW OF 40 TO 50KTS WILL CREATE A
POTENTIAL FOR DAMAGING WIND GUSTS IN HEAVY SHOWERS/STORMS DURING
WEDNESDAY. HAVE INCREASED POPS TO CATEGORICAL LEVELS WEDNESDAY INTO
WEDNESDAY NIGHT AND RAMPED UP EXPECTED QPF. WILL CONTINUE TO
HIGHLIGHT EVENT POTENTIAL IN THE HAZARDOUS WEATHER OUTLOOK.
GIVEN THE SLOWER TRACK OF THE UPPER LOW...FRONT MAY NOT MAKE IT
ACROSS THE AREA UNTIL THURSDAY. WILL KEEP CHANCES FOR SHOWERS IN
PLACE INTO THURSDAY WITH UPPER ENERGY HOLDING TO THE WEST. IMPROVING
CONDITIONS CAN BE EXPECTED FROM WEST TO EAST LATER THURSDAY INTO
FRIDAY WITH COOLER CONDITIONS. HIGH TEMPERATURES WILL HOLD MOSTLY IN
THE 60S WITH LOWS IN THE 40S AND 50S.
ANOTHER UPPER TROUGH AND FRONT COULD SWING THROUGH NEXT WEEKEND
BRINGING A RE-ENFORCEMENT OF COOLER TEMPERATURES AND PERHAPS AN
INCREASE IN CLOUD COVER. KEPT THE FORECAST DRY ATTM.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
MVFR FLGT CONDS PREVAIL...W/ LIFR CONTG AT CHO. DO NOT XPCT TOO
MUCH IMPRVMNT THRU NOON AS ARE OF SHRA CROSSES THE TERMINALS. WL
GO THE OPTIMISTIC RTE THEREAFTER...ALLOWING FOR VFR. THAT FCST HAS
LWR THAN TYPICAL CONFIDENCE LVLS. THE ALTERNATE SCENARIO WUD BE
FOR LWR FLGT CATEGORIES TO CONT INTO/THRU THE AFTN.
GDNC SUGGEST WIDESPREAD RESTRICTIONS FROM CIGS AND PERHAPS VIS AS
WELL DVLPG TNGT AND CONTG INTO TUE MRNG. LEANED A LITTLE MORE TOWARD
THE MAV/GFS FOR THE INTERMEDIATE PERIOD...BUT IF THE FORECAST WERE
TO GO WRONG IT WOULD BE THAT THE AFTERNOON PERIOD IS TOO
OPTIMISTIC.
WIDESPREAD VSBY AND CIG RESTRICTIONS EXPECTED ON WEDNESDAY INTO
WEDNESDAY NIGHT. POTENTIAL EXISTS FOR HEAVY RAINFALL...DAMAGING
WIND GUSTS AND A FEW THUNDERSTORMS. LOW CIGS AND VSBYS MAY HANG ON
INTO THURSDAY WITH IMPROVING CONDITIONS TO FOLLOW FROM WEST TO
EAST LATER THURSDAY INTO FRIDAY. VFR EXPECTED FOR THE START OF THE
WEEKEND.
&&
.MARINE...
NO CHGS TO THE MARINE FCST ATTM. SOUTHEAST FLOW HAS DEVELOPED AND
WILL REMAIN IN PLACE EARLY THIS WEEK. MODELS SUGGEST WINDS
INCREASING LATER TODAY AND TONIGHT. FEEL WINDS WILL BE BELOW SCA
CRITERIA TODAY...BUT ARE LIKELY TO INCREASE INTO THE 15 TO 20 KT
RANGE TONIGHT AND CONTINUE TUESDAY/TUESDAY NIGHT FOR MUCH OF THE
BAY AND LOWER PORTION OF THE TIDAL POTOMAC RIVER.
SMALL CRAFT CONDITIONS A GOOD BET WEDNESDAY INTO EARLY THURSDAY.
WINDS BELOW SCA LEVELS EXPECTED THROUGH THE END OF THE WEEK.
&&
.TIDES/COASTAL FLOODING...
TIDAL DEPARTURES REMAIN ARND 3/4 FT ABV ASTRO NORMALS. AT THAT
RATE...HIGH TIDE IS COMING IN ABV CAUTION STAGE BUT UNDER MINOR
FLOOD CRITERIA.
HOWEVER THE SUBSEQUENT HIGH TIDE CYCLE THAT OCCURS TONIGHT WILL
BE THE HIGHER OF THE NEXT TWO...AND BY THEN ANOMALIES MAY BE ABOVE
1 FT DUE TO SOUTHEAST WINDS. MINOR TIDAL FLOODING APPEARS LIKELY
AT ANNAPOLIS AND COASTAL FLOOD ADVISORY WILL EVENTUALLY BE
NECESSARY. CONFIDENCE IS LOWER AT OTHER LOCATIONS...AND WILL
DEPEND ON HOW MUCH ANOMALIES INCREASE BY HIGH TIDE BUT MINOR TIDAL
FLOODING CERTAINLY WILL BE POSSIBLE.
THE RISK FOR MINOR TIDAL FLOODING IS EXPECTED TO INCREASE
TUESDAY/TUESDAY NIGHT AS SOUTHEAST WINDS CONTINUE. BY
WEDNESDAY...THERE COULD ALSO BE THE RISK FOR MODERATE TIDAL FLOODING
AT SENSITIVE LOCATIONS. THE POTENTIAL FOR TIDAL FLOODING WILL
DECREASE ON THURSDAY AS THE FRONT MOVES THROUGH.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 PM EDT
TUESDAY FOR ANZ530>534-537-539>543.
&&
$$
SYNOPSIS...KRW
NEAR TERM...HTS
SHORT TERM...BPP
LONG TERM...KRW
AVIATION...HTS/BPP/KRW
MARINE...HTS/BPP/KRW
TIDES/COASTAL FLOODING...HTS/BPP/KRW
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
724 AM EDT MON OCT 13 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 404 AM EDT MON OCT 13 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEPENING UPR TROF
OVER THE CENTRAL CONUS AS POTENT SHRTWV DIGS INTO THE SRN PLAINS.
WITHIN THIS LARGER TROF...THERE IS A WEAKER SHRTWV LIFTING NEWD THRU
THE NRN PLAINS...AND SOME ISOLD-SCT SHOWERS IN THE LARGER SCALE
ISENTROPIC ASCENT/SW FLOW/AREA OF H85-5 QVECTOR CNVGC BTWN THAT
SHRTWV AND DEPARTING HI PRES OVER NEW ENGLAND HAVE MOVED INTO THE
UPR LKS DESPITE VERY DRY H7-9 LYR SHOWN ON THE 00Z GRB RAOB. THERE
IS ANOTHER AREA OF SHOWERS OVER MN UNDER THE SHARPER DEEP LYR
QVECTOR CNVGC CLOSER TO THE SHRTWV LIFTING NEWD IN THE NRN
PLAINS...BUT THERE IS LTL IN THE WAY OF PCPN BTWN THE ACTIVITY IN
MN/THE UPR LKS AND MORE WDSPRD SHRA/TS IN THE SCENTRAL PLAINS
ASSOCIATED WITH DEEPER SHRTWV IN THAT AREA DESPITE PWATS AS HI AS AN
INCH /UP TO 150 PCT OF NORMAL/ AT QUAD CITIES IOWA.
MAIN FCST CONCERNS THRU TNGT ARE FOCUSED ON POPS. STILL LOOKS LIKE
THE MOST WDSPRD...HEAVY RA WL IMPACT THE E HALF OF UPR MI TNGT
CLOSER TO RIBBON OF HIER PWAT/DVLPG FGEN. PER NCEP GUIDANCE...
FOLLOWED THE 00Z NAM/12Z ECMWF MOST CLOSELY FOR FCST DETAILS.
TODAY...AREA OF DEEPER MSTR/SOMEWHAT SHARPER ISENTROPIC ASCENT/AXIS
OF H85-5 QVECTOR CNVGC IS FCST TO MOVE NEWD AND PASS OUT OF UPR MI
BY NOON AND GIVE WAY TO SOME WEAK DEEP LYR QVECTOR DVGC/DRYING ABV
H7...SO EXPECT THE ISOLD-SCT SHOWERS IMPACTING UPR MI TO DIMINISH IN
THE AFTN. MEANWHILE...AS SHRTWV IN THE NRN PLAINS/ACCOMPANYING
QVECTOR CNVGC CONTINUES TO THE NE AND INTO NW ONTARIO...AREA OF
SHOWERS IN MN WL FOLLOW AND TEND TO MISS ALL BUT WRN LK SUP. BUT
WITH PERSISTENT SLY FLOW OF MOISTER AIR TO THE S...EXPECT OVERCAST
SKIES DESPITE THE DIMINISHING PCPN TREND. LATE IN THE DAY TOWARD 00Z
TUE...COMBINATION OF INCRSG UPR DVGC IN RRQ OF 100KT H3 JET MAX
SHIFTING INTO NW ONTARIO WITH NRN SHRTWV...AREA OF DEEP LYR QVECTOR
CNVGC APRCHG FM THE S AND ARRIVAL OF AXIS OF H85-7 FGEN IN COMMA
TAIL OF DEPARTING SHRTWV IN ONTARIO WL BRING A RETURN OF HIER POPS
TO AREAS NEAR THE WI BORDER/SCENTRAL.
TNGT...DEEP SSW FLOW E OF UPR TROF AXIS IS PROGGED TO LIFT PWAT TO
NEAR 1.5 INCHES OVER THE FAR SE CWA NEAR LK MI...NEARLY 250 PCT OF
NORMAL. IN CONCERT WITH UPR DVGC IN RRQ OF INTENSIFYING H3 JET MAX
IN NW ONTARIO AND AXIS OF SHARP H85-7 FGEN/ISENTROPIC ASCENT ON THE
300-305K SFCS /ABOUT H8-7/ NEAR FRONTAL ZN THAT IS FCST TO IMPACT
THE SE PORTION OF THE FA...EXPECT CATEGORICAL POPS/SOME MDT TO AT
TIMES HEAVY RA IN THIS AREA. THE WRN EXTENT OF THE HIER POPS/
HEAVIER RA IS SOMEWHAT IN QUESTION BECAUSE THE MAIN CUTOFF LO
ASSOCIATED WITH THE MORE VIGOROUS SRN BRANCH SHRTWV AND ACCOMPANYING
SHARPER DEEP LYR QVECTOR CNVGC ARE PROGGED TO STAY S OF THE UPR
LKS...WITH UPR DVGC THE MAIN FORCING MECHANISM FOR PCPN TO THE W.
THE 00Z NAM/12Z ECMWF SHOW SUFFICIENT DRYING OVER THE W IN THE WAKE
OF THE SHRTWV MOVING INTO ONTARIO AND SO FAR W OF THE FRONTAL ZN TO
SUPPORT LTL IF ANY PCPN OVER THE FAR W...SO TENDED TO LOWER POPS IN
THIS AREA. OTRW...ADDED SOME FOG OVER THE NCENTRAL WITH UPSLOPE NE
FLOW AND ACRS THE E WHERE THE PWAT IS FCST SO HI.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 357 AM EDT MON OCT 13 2014
TUE WILL SEE DECREASING RAIN CHANCES AS AN FGEN BAND ALONG AN
INVERTED SFC TROUGH MOVES E OF THE CWA. MODELS VARY ON EXACTLY WHERE
THE BAND WILL BE AT IN THE MORNING AND HOW FAST IT WILL MOVE E...BUT
AT LEAST FAR NWRN UPPER MI /FROM IWD THROUGH THE KEWEENAW/ WILL BE
DRY ALL DAY PER THE FARTHER W 00Z/13 GFS SOLUTION. THE 12Z/12 ECMWF
ONLY HAS 0.02 INCHES OF RAIN IN THE MORNING AT ERY. THE 00Z/13 NAM
TAKES THE MIDDLE GROUND...WHICH MAKES IT PREFERABLE GIVEN A LACK OF
PREFERENCE FOR THE GFS VS THE ECMWF. ALL THREE OF THESE MODELS HAVE
THE CWA DRY FROM 18Z THROUGH THE REST OF TUE.
AN ADDITIONAL CONCERN...ESPECIALLY DURING THE TUESDAY INTO TUESDAY
NIGHT TIME PERIOD IS THE POSSIBILITY FOR LARGE WAVES TO DEVELOP ON
THE TIGHTER PRESSURE GRADIENT ALONG THE INVERTED TROUGH. THESE WAVES
WOULD DEVELOP ON GUSTY NORTH TO NORTHEASTERLY WINDS....ALLOWING
WAVES TO REACH AROUND 8 FEET. THIS COULD CAUSE MINOR BEACH EROSION
ALONG THE MARQUETTE AND ALGER COUNTY SHORELINES.
THE ECMWF AND NAM KEEP THE CWA DRY FOR THE MOST PART TUE NIGHT
THROUGH WED WHILE THE GFS BRINGS LIGHT QPF AMOUNTS BACK INTO THE FAR
SERN CWA THROUGH THAT PERIOD. THE REASON FOR THE DISCREPANCY IS THAT
THE GFS SHIFTS THE UPPER LOW FROM CENTRAL IL TO SRN MI WHILE THE
OTHER MODELS KEEP IT OVER IL. BECAUSE OF THIS...THE ECMWF/NAM KEEP
THE UPPER RIDGE EXTENDING N OF THE UPPER LOW ACROSS THE CWA...WHICH
KEEPS THE AIRMASS MUCH DRIER AND FORCING FARTHER S. OPTED TO LOWER
POPS SOME DURING THE PERIOD TO ACCOUNT FOR THE DRIER TREND IN
GUIDANCE. AS HEIGHTS RISE DUE TO THE UPPER RIDGE MOVING N OF THE LOW
AND THE LOW ITSELF FILLING...THE AIRMASS WARMS PRETTY CONSIDERABLY.
850MB TEMPS AT 12Z TUE LOOK TO RANGE FROM 4C W TO 8C E...BUT
INCREASE TO AROUND 11 C OVER THE ENTIRE AREA BY 00Z THU.
DETAILS ARE MUCH LESS CERTAIN AFTER WED...BUT OVERALL THE MODELS
SHOW THE UPPER LOW LIFTING QUICKLY N AND MERGING WITH AN INCOMING
TROUGH THAT DEEPENS INTO A CLOSED LOW /OR AT LEAST A DEEP TROUGH/ AS
IT MOVES THROUGH THE REGION FRI AND SAT. CANNOT GET TOO SPECIFIC AT
THIS POINT GIVEN LACK OF CONFIDENCE...BUT CHANCES FOR PRECIP WILL BE
HIGHER WED NIGHT INTO SAT. A COLD FRONT MOVING THROUGH THU NIGHT OR
FRI WILL BRING COOLER CONDITIONS FRI THROUGH THE WEEKEND. MODELS
HAVE THEN BEEN TRENDING DRIER FOR SUN...SO WILL REFLECT THAT IN THE
FORECAST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 723 AM EDT MON OCT 13 2014
WITH INFLUX OF MORE LLVL MSTR IN PERSISTENT SLY FLOW IN ADVANCE OF
SLOWLY ARPCHG COLD FNT...EXPECT MVFR CONDITIONS TO DOMINATE TODAY AT
ALL 3 TAF SITES EVEN THOUGH ISOLD -SHRA WL TEND TO DRIFT TO THE NE. A
MORE WDSPRD RA WL DVLP TNGT AND IMPACT MAINLY THE E HALF OF UPR MI
FOLLOWING PASSAGE OF COLD FNT AND WSHFT TO AN UPSLOPE N DIRECTION
TNGT. IFR CONDITIONS ARE LIKELY AT ALL 3 AIRPORTS...ESPECIALLY AT SAW
WHICH WL BE CLOSER TO SHARPER DYNAMIC SUPPORT FOR THE RA AND DEEPER
MSTR. LIFR CONDITIONS WITH SOME FOG ARE A GOOD BET FOR THIS SITE MUCH
OF THE NGT. DEPENDING ON HOW QUICKLY DRY AIR MOVES INTO WRN UPR MI
LATE...CONDITIONS MAY IMPROVE TO MVFR AT IWD AND CMX LATE IN THE TAF
PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 357 AM EDT MON OCT 13 2014
A WEAKENING PRESSURE GRADIENT ACROSS THE AREA WILL LEAD TO WINDS
WILL DROPPING BELOW 10KT ACROSS THE LAKE BY THIS AFTERNOON. AS A LOW
PRESSURE SYSTEM SLOWLY LIFTS NE...WINDS WILL BECOME N TO NE TONIGHT
AND WILL INCREASE LATE. TUE AND TUE NIGHT...EXPECT N TO NE WINDS UP
TO 20KT ON WRN LAKE SUPERIOR AND UP TO 25KT ON ERN LAKE SUPERIOR.
THE LOW WILL THEN WEAKEN AS IT DRIFTS NE ACROSS THE GREAT LAKES
REGION WED/THU...ALLOWING WINDS TO DIMINISH. WINDS SHOULD BE UNDER
10KT BY THU. ANOTHER LOW PRESSURE SYSTEM TRACKING ACROSS SRN CANADA
THU WILL THEN MERGE WITH THE REMNANT GREAT LAKES LOW ON FRI IN THE
VICINITY OF JAMES BAY. THIS WILL RESULT IN INCREASING W TO NW INTO
THE 15-25KT RANGE ON FRI.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...KC
MARINE...TITUS
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
702 AM CDT Mon Oct 13 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 355 AM CDT Mon Oct 13 2014
Warm front extending from near Joplin to Jefferson City and through
the St. Louis Metro area northeast to near Decatur will continue to
lift slowly north today as a strong trof and associated wound up
surface low moves northeast through Missouri. Strong low level warm
advection ahead of the system will produce scattered to numerous
showers and thunderstorms this morning. All short-range guidance is
very consistent in developing a wave of convection this morning
with a break before another round this afternoon. With some dry
time and a bit of insolation, MUCAPE in excess of 1000 J/Kg should
result. Very strong wind fields and plenty of shear will likely
produce severe thunderstorms this afternoon...primarily along and
east-southeast of the I-44 corridor. 4km NSSL and NCEP WRF models
along with the HRRR develop a strong squall line which moves rapidly
east this afternoon. SPC day 1 outlook has about the southeast 1/2
to 2/3 of the area in a slight risk with the moderate clipping
Reynolds, Iron and Madison counties. Primary concern will be
damaging winds given the very strong wind fields, and there could be
a few tornadoes as 0-1km helicity is forecast to be in excess of 200
m2/s2. Lack of steep lapserates aloft precludes a high hail risk.
Carney
.LONG TERM: (Tonight through Sunday)
Issued at 355 AM CDT Mon Oct 13 2014
A strong storm system is still set to deepen and slowly move through
our region over the next few days. It will initially close off this
evening over far southwestern MO and then not begin to pull away
from our region to the east until Wednesday, but its influences will
still be felt thru Wednesday night and perhaps into Thursday.
The main severe thunderstorm threat from this system will be on its
front-end, and is expected to be ongoing early this evening from the
lower MS Valley into southern IL. The convective mode by this time
is expected to be a squall line with damaging winds and isolated
imbedded tornadoes. All indications, though, is that the severe
thunderstorm threat should end by 9pm across our region as it pushes
east.
Heading into late tonight and through Wednesday, the primary focus
at this point will be the deformation zone pcpn, which will be best
focused down our way using the expected location of the TROWAL and
decently strong lo-level convergence. With a system this wrapped up
expected, went above MAV MOS PoPs, tapering back to MOS by Wednesday
night. Added in some small mentionable PoPs for Thursday in parts
of southern IL with the trends all heading in that direction, with
stronger indications of more persistent, deep cyclonic flow.
MOS temps thru Wednesday look reasonable, but adjusted daytime maxes
a bit lower where we expect the most peristent, and high, rain
chances to be.
Northwest upper flow is still on track for late week and next
weekend, with a couple of glancing blows from upper level
disturbances on Friday and Sunday, but moisture looks severely
limited enough to hold off on chance mention for now. Temps should
be near seasonal normals.
TES
&&
.AVIATION: (For the 12z TAFs through 12z Tuesday Morning)
Issued at 634 AM CDT Mon Oct 13 2014
Difficult aviation forecast today. A warm front will lift slowly from
around the I-70 corridor northward today. Numerous and widespread
thunderstorms will affect the region, culminating in a strong squall
line this afternoon which will affect areas along and south of
I-70. This squall line will produce wind gusts in excess of 60 kts
as it passes. Generally speaking, the eastern Ozarks should stay
MVFR today outside of thunderstorms. IFR ceilings/visibilities
will lift slowly this morning from I-70 north as the warm front
moves, but think ceilings will stay below 2,000 FT, especially as
thunderstorms roll through. Am very unsure of what
ceilings/visibilities will do after sunset tonight as the low
pressure currently over Oklahoma moves into central Missouri.
However, think ceilings should stay below 2,000 FT and
visibilities could drop down to IFR again in fog and/or light rain
or drizzle.
Specifics for KSTL:
Scattered showers and a few thunderstorms with IFR ceilings will
prevail this morning until the warm front which is just south of
the terminal moves north. This may happen as early as 14Z or may
be as late as 16-18Z depending on which model you believe.
However, wind should eventually swing around to the south-
southwest and ceilings should improve slightly, though am not
optimistic about any ceilings higher than 1,900 FT today. A strong
squall line capable of producing winds in excess of 60 kts will
move through the area this afternoon...I suspect the truly severe part
of the line will stay south of Lambert, but I cannot rule out a
direct impact on the terminal. Am very unsure of what
ceilings/visibilities will do after sunset tonight as the low
pressure currently over Oklahoma moves into central Missouri.
However, think ceilings should stay below 2,000 FT and
visibilities could drop down to IFR again in fog and/or light rain
or drizzle.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
551 AM CDT MON OCT 13 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 316 AM CDT MON OCT 13 2014
MAIN FORECAST CONCERNS WILL BE ENDING PRECIPITATION THIS MORNING AND
WINDS FOR TODAY.
LATEST RADAR TRENDS SHOW SHOWERS IN THE WESTERN PART OF THE FORECAST
AREA THAT ARE MOVING SOUTH AND ANOTHER AREA OF SHOWERS TO THE
SOUTHEAST THAT IS MOVING TO THE NORTH. SURFACE ANALYSIS HAS A COLD
FRONT JUST ABOUT TO EXIT THE FAR SOUTHEAST PART OF THE FORECAST AREA
ALREADY THIS MORNING.
SHORT TERM MODELS HAVE A VARIETY OF SOLUTIONS FOR THE CURRENT
PRECIPITATION. THE HRRR AND RAP TRY TO BRING THE SHOWERS TO THE
SOUTHEAST NORTH INTO THE FORECAST AREA...BUT THE TREND ON THESE HAVE
BEEN TO WEAKEN A LITTLE AS THEY MOVE TO THE NORTH. ON THE OTHER HAND
THE 4KM WRF KEEPS IT MOSTLY TO THE SOUTHEAST OF THE AREA. THE
PRECIPITATION TO THE WEST IS NOT HANDLED WELL WITH THE MODELS. WITH
THAT IN MIND...HAVE KEPT POPS IN THE SOUTHERN/SOUTHEASTERN PART OF
THE FORECAST AREA THROUGH THE MORNING HOURS...BUT LOWERED THE
CHANCES. HAVE KEPT THUNDER OUT SINCE THE MUCAPE IS NON-EXISTENT AND
THERE HAS ONLY BEEN A RARE LIGHTNING STRIKE IN THE PAST COUPLE OF
HOURS.
NORTH OR NORTHWEST WINDS HAVE ALREADY STARTED INCREASING THIS
MORNING. MOST LOCATIONS HAVE WINDS AT 15 TO 20 MPH WITH GUSTS TO
AROUND 25 MPH ALREADY. EXPECT THE TREND TO INCREASE AND AS THE SUN
RISES THIS MORNING AND THE INVERSION BREAKS STRONGER WINDS WILL MIX
DOWN. WINDS AT 850MB ARE STRONGEST AT 12Z THIS MORNING...BUT REMAIN
AROUND 40 KNOTS THROUGH THE AFTERNOON. WILL KEEP THE WIND ADVISORY
THROUGH THE DAY.
AS THE SUN SETS THIS EVENING...WINDS WILL DROP OFF BUT STILL REMAIN
BREEZY FOR A COUPLE OF HOURS. LATER TONIGHT A SURFACE HIGH PRESSURE
SYSTEM WILL START TO BUILD INTO THE AREA AND WINDS WILL DIMINISH.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 316 AM CDT MON OCT 13 2014
GUIDANCE SUGGESTS THE LONG TERM FORECAST PERIOD WILL START WITH AN
UPPER TROPOSPHERIC TROUGH OVER CENTRAL AND EASTERN PORTIONS OF THE
CONUS...AND A RIDGE OVER THE WEST. THE RIDGE OVER THE WEST IS
EXPECTED TO MOVE EAST INTO THE CENTRAL CONUS ON WEDNESDAY...BEFORE
WEAKENING THUS ALLOWING FOR QUASI-ZONAL UPPER TROPOSPHERIC FLOW OVER
OUR AREA ON THURSDAY. A STRENGTHENING UPPER TROPOSPHERIC TROUGH OVER
THE GREAT LAKES REGION IS THEN EXPECTED TO TURN OUR FLOW MORE
NORTHWESTERLY FRIDAY THROUGH SUNDAY.
AN OVERALL LACK IN OMEGA SHOULD PROMOTE DRY CONDITIONS TO OUR AREA AS
THE AFOREMENTIONED UPPER TROPOSPHERIC RIDGE AXIS MOVES OVER THE
REGION. SUCH HAS BEEN PRESENTED IN THE OFFICIAL FORECAST. ONE COULD
ARGUE THAT THE PASSAGE OF A WEAK UPPER TROPOSPHERIC PERTURBATION...OR
PERHAPS ENHANCED JET DYNAMICS...COULD BRING CHANCES FOR LIGHT
PRECIPITATION TO THE REGION THURSDAY ONWARD...BUT AT THIS TIME
TROPOSPHERIC MOISTURE APPEARS AS THOUGH IT WILL BE EXTREMELY LACKING
THURSDAY THROUGH SUNDAY AND AS A RESULT...ALSO WENT AHEAD WITH DRY
CONDITIONS THROUGH THE WEEKEND.
SOUTHERLY BOUNDARY-LAYER RETURN FLOW IS EXPECTED TO OVERTAKE THE
REGION STARTING ON WEDNESDAY AND AS A RESULT...THERMAL ADVECTION
THROUGH THE BOUNDARY LAYER SHOULD PROMOTE A GENERAL WARMING TREND
FROM DAY TO DAY BETWEEN TUESDAY AND THURSDAY...WITH HIGHS CLIMBING
FROM THE 60S ON TUESDAY TO THE LOW TO MID 70S BY THURSDAY. THE
PASSAGE OF A WEAK BOUNDARY-LAYER BAROCLINIC ZONE IS THEN EXPECTED TO
BRING A SLIGHT COOL DOWN TO FINISH THE FORECAST PERIOD...WITH HIGHS
BACK IN THE 60S FRIDAY THROUGH SUNDAY. TUESDAY NIGHT
/ WEDNESDAY MORNING LOWS IN THE MID TO UPPER 30S WILL ALSO BE SHORT
LIVED AS BOUNDARY-LAYER THERMAL ADVECTION OVERTAKES THE AREA...WITH
LOWS GENERALLY IN THE 40S THEN EXPECTED THROUGH THE REMAINDER OF THE
FORECAST PERIOD.
&&
.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 549 AM CDT MON OCT 13 2014
WINDY CONDITIONS ARE EXPECTED TODAY. NORTH WINDS WILL INCREASE AS
THE SUN COMES UP THIS MORNING AND CONTINUE THROUGH THE
DAY...DECREASING AS THE SUN GOES DOWN THIS EVENING. CLOUDS WILL BE
ON THE DECREASE AS WELL.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NEZ039>041-046>049-
060>064-072>077-082>087.
KS...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR KSZ005>007-017>019.
&&
$$
SHORT TERM...JCB
LONG TERM...BRYANT
AVIATION...JCB
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
603 AM MDT MON OCT 13 2014
.UPDATE...
EXPIRED WIND ADVISORY ACROSS NORTHEASTERN NEW MEXICO. WINDS HAVE
TAPERED OFF TO BETWEEN 15 AND 25MPH WITH GUSTS UP TO 35 MPH FROM
CLAYTON TO CLOVIS. THE 09Z HRRR 10-METER WIND SHOWS WINDS WILL
INCREASE SLIGHTLY AGAIN FOR AN HOUR OR TWO LATE THIS MORNING BEFORE
TAPERING OFF AGAIN THIS AFTERNOON. WILL NOT EXTEND THE HIGHLIGHT
FOR THIS BRIEF WINDIER PERIOD AS THE MAIN IMPACT WINDOW HAS ENDED
AND THESE WINDS ARE NOT EXPECTED TO BE NEARLY AS STRONG AS WHAT
WAS EXPERIENCED OVERNIGHT AND LAST EVENING.
GUYER
&&
.PREV DISCUSSION...556 AM MDT MON OCT 13 2014...
.AVIATION...
12Z TAF CYCLE
STILL SOME BREEZY TO WINDY CONDITIONS ACROSS MAINLY THE EASTERN
BORDER COUNTIES OF NM INTO MIDDAY OR EARLY AFTN THEN DIMINISHING
SOME THROUGH THE MID AND LATE AFTN. SOME GUSTS MAY STILL REACH
BETWEEN 25 AND 35KT OUT EAST WITH TCC A LIKELY IMPACTED TAF SITE.
A FEW FOG POCKETS POSSIBLE THROUGH MID MORN ACROSS SOME OF THE
COLDER AND WETTER MOUNTAIN VALLEYS IN NORTHERN NM. OTHERWISE VFR
CONDITIONS BY FAR THE RULE AS DRY AND DIMINISHING N TO NW FLOW
ALOFT WILL BE IN PLAY THROUGH THE END OF THE FCST PERIOD.
43
&&
.PREV DISCUSSION...344 AM MDT MON OCT 13 2014...
.SYNOPSIS...
THE STORM SYSTEM THAT BROUGHT ALL THE STRONG WINDS TO THE REGION
SUNDAY WILL GRADUALLY EXIT THE AREA TODAY. CONDITIONS WILL REMAIN
WINDY OVER THE EASTERN PLAINS ALONG THE TEXAS STATE LINE THROUGH
LATE THIS MORNING. OTHERWISE...TEMPERATURES WILL BE A LITTLE BELOW
NORMAL FOR MID OCTOBER WITH LOTS OF SUNSHINE. CHILLY TEMPERATURES
WILL DEVELOP AGAIN TONIGHT WITH CLEAR SKIES AND LIGHT WINDS. VERY
PLEASANT WEATHER IS ON TAP TUESDAY THROUGH THURSDAY WITH WARMER
TEMPERATURES AND SUNNY SKIES.
&&
.DISCUSSION...
MAIN CONSIDERATIONS THIS MORNING WERE STRENGTH AND DURATION OF WINDY
CONDITIONS ACROSS THE FAR EASTERN PLAINS...AND FREEZING TEMPERATURES
OVER PORTIONS OF NORTHERN NM TONIGHT. LATEST OBSERVATIONS SHOW SURFACE
WINDS ARE STILL ELEVATED FROM CLAYTON TO TUCUMCARI AND CLOVIS...BUT
SPEEDS ARE ONLY MARGINAL TO SLIGHTLY UNDER ADVISORY CRITERIA. WINDS
MAY COME BACK UP WITH INITIAL MIXING THIS MORNING FOR A FEW HOURS SO
THE POTENTIAL IS THERE FOR AN HOUR OR TWO OF ADVISORY WINDS AGAIN.
WILL NOT HOWEVER EXTEND PRODUCT SINCE MAIN IMPACT PERIOD IS OVER AND
WINDS WILL NOT BE NEAR AS STRONG AS WHAT HAS ALREADY OCCURRED. THE
SURFACE PRESSURE GRADIENT IS PROGGED TO WEAKEN SIGNIFICANTLY THROUGH
THE MORNING SO CONFIDENCE ON EXTENSION OF THE ADVISORY IS LOW. TEMPS
ARE ALSO STRUGGLING TO FALL OVER THE NW PLATEAU WHERE WINDS REMAINED
ELEVATED THROUGH 3 AM...SO WILL CANCEL THAT PORTION OF THE FREEZE
WARNING. THE AREA AROUND ESPANOLA IS ALSO NOT FALLING AS MUCH AS
DESIRED FOR FREEZING CONDITIONS...BUT POINTS IMMEDIATELY TO THE
NORTH AND WEST MAY HIT FOR AN HOUR OR TWO.
THE NEXT CHALLENGE WAS TONIGHTS TEMPS. THE BULK OF MOS GUIDANCE HAS
READINGS ONLY HOVERING NEAR FREEZING ACROSS FREEZE ZONES IN THE
NORTH...EXCEPT THE MET...WHICH IS MUCH COLDER. WENT WITH CONSENSUS
GUIDANCE AND WILL ALLOW DAY SHIFT TO TAKE ANOTHER LOOK BEFORE A
FREEZE WARNING IS ISSUED. OTHERWISE...TEMPS WILL ACTUALLY BE CLOSE
TO NORMAL TONIGHT FOR MOST AREAS UNDER CLEAR SKIES AND LIGHT WINDS.
THE PICK OF THE WEEK IS TUESDAY AS HIGH PRESSURE BEGINS BUILDING
WEST OF NM. THIS WILL ALLOW FOR LIGHT WINDS...BRIGHT SUNNY SKIES...
AND WARMING TEMPS. TUESDAY NIGHT WILL BE CHILLY AGAIN BUT WARMER
THAN TONIGHT. THE H5 HIGH CENTER WILL CREST OVER SE ARIZONA AT 589DM
WEDNESDAY MORNING THEN BREAK DOWN OVER NM THROUGH WEDNESDAY NIGHT.
YET ANOTHER DELIGHTFUL DAY IS ON TAP WITH EVEN WARMER TEMPS...SUNNY
SKIES...AND DRY CONDITIONS. SURFACE LEE TROUGHING WILL INCREASE OVER
THE EAST AND SUBSEQUENTLY WILL THE TEMPS WITH KATABATIC FLOW. HIGHS
WILL AVERAGE BTWN 5 AND 15F ABOVE NORMAL. ZONAL FLOW IS EXPECTED TO
INCREASE THURSDAY BEHIND THE FLATTENING RIDGE. A WEAK BACK DOOR FRONT
ENTERING THE PLAINS WILL TREND TEMPS BACK TOWARD NORMAL.
GUYER
&&
.FIRE WEATHER...
BRISK NORTHERLY WINDS ACROSS A GOOD PORTION OF THE EASTERN PLAINS
WILL EASE BACK JUST A BIT THROUGH THE EARLY MORN HOURS IN EAST
QUARTER TO THIRD OF NM...BUT SHOULD...FOR A 2 TO 4 HOUR PERIOD MID
MORN TO AROUND MIDDAY TODAY...INCREASE BACK TO NEAR THE 20 TO NEARLY
35 MPH RANGE. DURING THIS CRITICAL WIND SPEED PERIOD...RH VALUES NOT
EXPECTED TO DROP TO CRITICAL VALUES. THIS PLUS THE RECENT DECENT
RAINS ACROSS A GOOD PORTION OF THIS AREA WOULD PRECLUDE ANY RED FLAG
CONDITIONS. IN FACT AFTER THE MIDDAY OR EARLY AFTN PERIOD...IT LOOKS
LIKE CRITICAL FIRE WX CONDITIONS ARE NOT LIKELY THROUGH THE WHOLE
WEEK AS WINDS WILL DECREASE SIGNIFICANTLY LATER TODAY AND STAY BELOW
CRITICAL VALUES FOR SOME TIME. TEMPERATURES TO BE COOLER THAN THE
NORM TODAY...BUT BY TUE AFTN LOOKING AT VALUES JUST A FEW DEGREES
EITHER SIDE OF SEASONAL NORMS. THEREAFTER ABOVE NORMAL VALUES INTO
THIS NEXT WEEKEND. VENTILATION RATES GENERALLY VERY GOOD TO
EXCELLENT EAST THIRD...MOSTLY GOOD NORTH AND POOR TO FAIR GENERALLY
ELSEWHERE. EXPECT BETTER RADIATIONAL COOLING AND STRONGER TEMP
INVERSIONS TONIGHT INTO EARLY TUESDAY MORNING. COLDER TEMPERATURES
CAN BE EXPECTED WITH MORE READINGS AT OR BELOW FREEZING...INCLUDING
THE POTENTIAL FOR A FREEZE IN SOME OF THE NORTHEAST HIGHLANDS...
ESTANCIA VALLEY...AND OTHER SHELTERED LOCATIONS.
A PROGRESSIVE UPPER RIDGE WILL EASE INTO NM TUE. DESPITE THE
AFOREMENTIONED WARM-UP...LOOK FOR POOR VENTILATION RATES EXCEPT
PERHAPS IN THE FAR EAST. DRY AND CLEAR CONDITIONS OTHERWISE AREAWIDE
TUE.
THE REMAINDER OF THE WORK WEEK APPEARS TO REMAIN DRY AND TRANQUIL.
A WIND SHIFT IN THE EAST COULD LOWER TEMPERATURES A FEW TO SEVERAL
DEGREES IN THE EAST FRIDAY...BUT CONDITIONS WILL STILL BE FAIRLY
TRANQUIL. LOOKING AT SOME MINOR TO MODERATE IMPROVEMENT IN
VENTILATION RATES WED THROUGH FRI...BUT GENERALLY NO BETTER THAN
FAIR TO GOOD.
43
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING UNTIL 9 AM MDT THIS MORNING FOR THE FOLLOWING
ZONES...NMZ517.
&&
$$
AREA FORECAST DISCUSSION
NWS BUFFALO NY
730 AM EDT MON OCT 13 2014
.SYNOPSIS...
A WARM FRONT WILL MOVE NORTH ACROSS THE REGION TODAY BRINGING A
FEW LIGHT SHOWERS AND MILD TEMPERATURES. TEMPERATURES WILL SOAR
WELL ABOVE NORMAL ON TUESDAY WITH MAINLY DRY WEATHER. A COLD FRONT
WILL THEN SLOWLY CROSS THE REGION WEDNESDAY WITH SHOWERS AND
POSSIBLY A THUNDERSTORM. SHOWERS WILL CONTINUE THURSDAY AS LOW
PRESSURE MOVES JUST NORTH OF THE AREA WITH TEMPERATURES GRADUALLY
COOLING BACK TO NEAR AVERAGE BY NEXT WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE WAS SITUATED OFF THE SOUTHERN NEW ENGLAND COAST
THIS MORNING. STRENGTHENING RETURN FLOW OVERSPREADING WESTERN NEW
YORK RESULTING IN INCREASING CLOUD COVER AND RISING TEMPERATURES.
REGIONAL RADARS SHOWING LITTLE IN THE WAY OF SHOWER ACTIVITY OTHER
THAN A FEW SPRINKLES AT THIS POINT SUGGESTING WEAK LARGE SCALE
FORCING.
WARM AIR/MOISTURE ADVECTION WILL BE MAINTAINED TODAY AS DIFFUSE
WARM FRONT MOVES NORTHWARD INTO THE REGION. FORCING WILL REMAIN
VERY LIMITED WITH ONLY A FEW LIGHT SHOWERS EXPECTED. THIS IS
SUPPORTED BY LATEST HRRR RUNS SHOWING VERY LIMITED ACTIVITY
THROUGH THE DAY TODAY.
TEMPERATURES TODAY LOOK TO BE AT LEAST 10 DEGREES ABOVE NORMAL AS
850MB TEMPERATURES RISE TO AROUND +11C TO +13C BY AFTERNOON...
SUPPORTING HIGHS IN THE LOWER 70S ACROSS LOWER ELEVATIONS FROM
THE GENESEE VALLEY WESTWARD...WITH 60S MORE PREVALENT ACROSS THE
SOUTHERN TIER AND NORTH COUNTRY.
TONIGHT...THERE STILL COULD BE A FEW WARM ADVECTION DRIVEN SHOWERS
BUT FOR THE MOST PART CLOUDY SKIES EXPECTED. TEMPERATURES REMAINING
MILD UNDERNEATH CLOUDS AND SOUTHERLY FLOW WITH LOWS ONLY DROPPING
INTO THE UPPER 50S TO LOWER 60S.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
IT WILL BE UNSEASONABLY MILD AND INCREASINGLY UNSETTLED DURING THIS
PERIOD AS A HIGHLY AMPLIFIED PATTERN...FEATURING AN ANOMALOUSLY DEEP
(-3 STD) TROUGH OVER THE MISSISSIPPI VALLEY...WILL GENERATE A 555DM
CLOSED LOW OVER THE OHIO VALLEY. THIS DOMINANT BLOCK WILL REMAIN TO
OUR WEST THROUGH THIS PERIOD...SO BEING ON THE `WARM` SIDE OF THE
FEATURE...OUR FORECAST AREA WILL BE GUARANTEED TO EXPERIENCE ABOVE
NORMAL TEMPERATURES. IN FACT...TEMPERATURES ON TUESDAY WILL BE
DOWNRIGHT SUMMER LIKE WITH READINGS MORE TYPICAL OF LATE JULY/EARLY
AUGUST. WHILE THE MERCURY WILL TREND LOWER AFTER THAT POINT...THEY
WILL MOST CERTAINLY REMAIN ABOVE NORMAL THROUGH AT LEAST THURSDAY.
BY THE TIME WE OPEN THIS PERIOD ON TUESDAY...A MID LEVEL
CIRCULATION WILL HAVE ALREADY TAKEN SHAPE OVER MISSOURI. ITS
ATTENDANT SUB-1000MB SFC LOW OVER ILLINOIS WILL LIKELY OCCLUDE BY
THE END OF THE DAY...MARKING THE PEAK STRENGTH OF THE OVERALL
SYSTEM. MEANWHILE DOWNSTREAM..A 40KT SOUTHERLY LOW LEVEL JET WILL
PUMP H85 TEMPS OF +15/16C ACROSS OUR FORECAST AREA. BEING DEEP
WITHIN THE WARM SECTOR OF THE STORM SYSTEM...THIS WILL SEND OUR
AFTERNOON HIGHS TO BETWEEN 75 AND 80...WITH THE VALLEYS AND LAKE
PLAINS WEST OF ROCHESTER LIKELY PUSHING INTO THE LOWER 80S. THE
ANOMALOUSLY STRONG SOUTHERLY FLOW WILL NOT ONLY HELP TO PRODUCE
UNUSUAL WARMTH ACROSS OUR REGION...BUT WILL KEEP PCPN FROM THE
AFOREMENTIONED SYSTEM WELL TO OUR WEST.
THE MATURE...VERTICALLY STACKED SYSTEM WILL BE CENTERED OVER
ILLINOIS TUESDAY NIGHT WHILE AN OCCLUDED SFC FRONTAL BOUNDARY WILL
STRETCH SOUTHWARDS ALONG THE SPINE OF THE APPALACHIANS. A 45-50KT
LOW LEVEL JET AHEAD OF THE SYSTEM WILL CONTINUE TO RETARD THE
EASTWARD PROGRESSION OF THE ASSOCIATED SHOWER ACTIVITY OVER OUR
REGION...SO WILL CONTINUE THE TREND OF SLOWING THE ONSET OF PCPN.
WILL BACK OFF POPS TO CHC FOR THE WESTERN COUNTIES AND SLGT CHC FOR
EASTERN LAKE ONTARIO REGION. WHILE THE STRONG LLJ WILL TEMPORARILY
KEEP THE PCPN TO OUR WEST...IT WILL ADVECT PWAT VALUES OF 1.5 TO
1.75" INTO OUR AREA FOR LATE TUESDAY NIGHT AND WEDNESDAY...SETTING
THE STAGE FOR A POTENTIALLY VERY WET 18 HOUR PERIOD. TUESDAY NIGHT
LOWS WILL GENERALLY RANGE FROM 60 TO 65...WHICH WILL BE SOME 20
DEGREES F ABOVE NORMAL. ANOTHER WAY OF LOOKING AT THE ANOMALOUS
NATURE OF THESE VALUES IS THAT THEY WILL ACTUALLY BE NOTABLY HIGHER
THAN WHAT THE DAYTIME HIGHS SHOULD BE FOR THIS TIME OF YEAR.
ON WEDNESDAY...THE STACKED LOW WILL SLOWLY CROSS THE MID WEST WHILE
THE AXIS OF DEEPEST MOISTURE ASSOCIATED WITH ITS SFC OCCLUDED FRONT
WILL PUSH ACROSS THE WESTERN COUNTIES OF NEW YORK. GIVEN PWAT VALUES
IN THE VCNTY OF 1.75"...LIFT PROVIDED BY A STRONGLY DIVERGENT UPPER
LEVEL FLOW AND 40+KT LOW LEVEL JET JUST AHEAD OF THE OCCLUDED FRONT
SHOULD PRODUCE WIDESPREAD SHOWERS WITH RAINFALL LIKELY REACHING A
HALF TO ONE INCH OVER THE WESTERN COUNTIES. WHILE THE AIRMASS WILL
ONLY BE MARGINALLY UNSTABLE...THE SYNOPTIC FORCING COULD BE ENOUGH
TO TOUCH OFF AN EMBEDDED THUNDERSTORM OR TWO. WILL USE CAT POPS OVER
THE WESTERN COUNTIES AND LIKELY EAST OF LK ONTARIO.
THE CLOSED LOW WILL SLOWLY START TO OPEN UP AS IT MAKES ITS WAY TO
SOUTHERN LOWER MICHIGAN WEDNESDAY NIGHT...WHILE THE SFC OCCLUSION
WILL MAKE ITS WAY ACROSS OUR FINGER LAKES REGION. THIS WILL PLACE
SITES FROM THE FINGER LAKES EAST IN THE PRIME AREA FOR WIDESPREAD
SHOWERS...WITH THE ACTIVITY OVER THE FAR WESTERN COUNTIES TAPERING
OFF DURING THE COURSE OF THE NIGHT AS A DRY SLOT WORKS IN BEHIND THE
OCCLUSION.
THE FILLING UPPER LEVEL STORM SYSTEM WILL PUSH NORTH ACROSS LOWER
MICHIGAN ON THURSDAY...WHILE ITS SUPPORTING LONGWAVE TROUGH WILL
BECOME NEGATIVELY TILTED OVER THE LOWER GREAT LAKES. AT THE SFC...
THE OCCLUSION WILL EXIT THE EASTERN LAKE ONTARIO REGION...BUT NOT
BEFORE PRODUCING A FEW MORE HOURS OF SHOWERS DURING THE MORNING.
WHILE SYNOPTIC MOISTURE WILL ROTATE BACK ACROSS THE LOWER GREAT
LAKES BEHIND THE AFOREMENTIONED DRY SLOT...THERE WILL BE A LACK OF
ANY SIGNIFICANT FORCING MECHANISM TO SUPPORT MUCH IN THE WAY OF
SHOWERS WITHIN THE BASE OF THE UPPER LEVEL TROUGH...SO WILL ONLY USE
CHC POPS FOR THE WESTERN COUNTIES.
THE BASE OF THE NEGATIVELY TILTED LONGWAVE TROUGH WILL PUSH ACROSS
OUR FORECAST AREA THURSDAY EVENING BEFORE EXITING DURING THE
OVERNIGHT HOURS. LOW LEVEL RIDGING AND A GENERAL LACK OF ANY
SIGNIFICANT FORCING SHOULD NOT DO MUCH TO PROMOTE ANY ORGANIZED
SHOWER ACTIVITY...SO WILL BACK OFF ON POPS AND ONLY USE LOW CHC.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
THE WEATHER IS NOT EXPECTED TO BE NEARLY AS ACTIVE DURING THIS
PERIOD...ALTHOUGH WE CAN ANTICIPATE A TREND TOWARDS LOWER...MORE
SEASONABLE TEMPERATURES.
AS ENERGY WITHIN THE EXITING STORM SYSTEM PUSHES NORTH ACROSS QUEBEC
ON FRIDAY...A BROAD LONGWAVE TROUGH WILL BE LEFT ACROSS MUCH OF
EASTERN CANADA AND THE GREAT LAKES. THIS TROUGH WILL BECOME
RE-ENERGIZED (`RELOAD` IF YOU WILL) DURING THE COURSE OF THE DAY AS
A ROBUST SHORTWAVE OVER THE CANADIAN PRAIRIES WILL PUSH SOUTHEAST
ACROSS THE UPPER MISSISSIPPI VALLEY. THIS WILL LEAD TO SOME WEAK
RIDGING OVER THE LOWER GREAT LAKES...ENOUGH TO LIKELY KEEP THE DAY
RAIN FREE. H85 TEMPS ARND 8C WILL SUPPORT AFTERNOON HIGHS IN THE
60S.
THE AFOREMENTIONED SHORTWAVE WILL DIG INTO...AND THEREBY
SHARPEN...THE BASE OF THE LONGWAVE TROUGH OVER THE LOWER GREAT LAKES
LATE FRIDAY NIGHT AND SATURDAY. THIS SHOULD PUSH A COLD FRONT ACROSS
OUR REGION...PRODUCING SOME SCATTERED SHOWERS IN THE PROCESS.
BY SUNDAY...THE TROUGH WILL BE CENTERED OVER THE ST LAWRENCE VALLEY
WITH DEEP COLD ADVECTION OVER OUR REGION SENDING H85 TEMPS TO NEAR
2C. THIS WILL BE COLD ENOUGH TO CREATE SOME LAKE INDUCED INSTABILITY
WITH NUISANCE LAKE EFFECT RAIN SHOWERS EAST OF BOTH LAKES. HIGHS
SUNDAY AFTERNOON SHOULD ONLY BE IN THE LOW TO MID 50S.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
VFR FLIGHT CONDITIONS WILL PREVAIL ACROSS MOST OF THE AREA THROUGH
THE TAF CYCLE...WITH THE EXCEPTION OF THE HIGHER TERRAIN.
WARM ADVECTION PATTERN WILL CONTINUE TO INCREASE TODAY WHICH WILL
HELP ADVECT LOW LEVEL MOISTURE NORTHWARD WITH ABUNDANT CLOUD COVER
CONTINUING THROUGH MUCH OF THE DAY. CIGS SHOULD BE PRIMARILY
LOW VFR ACROSS THE LOWER ELEVATIONS OF WESTERN NEW YORK AS SOUTHERLY
DOWNSLOPE WINDS PREVAIL. ACROSS THE HIGHER TERRAIN OF THE SOUTHERN
TIER EXPECT MVFR CIGS TO CONTINUE THROUGH AT LEAST THE FIRST HALF OF
TODAY...WITH SOME IFR POSSIBLE ACROSS THE HIGHEST ELEVATIONS.
A WEAK LOW LEVEL JET WILL CROSS THE REGION THIS MORNING WITH WINDS
INCREASING TO AROUND 30 KNOTS JUST OFF THE DECK. IT APPEARS WIND
SPEEDS WILL NOT BE QUITE HIGH ENOUGH TO PRODUCE TRUE LOW LEVEL WIND
SHEAR. THERE WILL BE A BETTER CHANCE FOR LOW LEVEL WIND SHEAR LATE
TONIGHT AS A 40 KNOT JET AXIS FOCUSES ON WESTERN NEW YORK.
OUTLOOK...
TUESDAY...MAINLY VFR.
WEDNESDAY...AREAS OF MVFR WITH SHOWERS LIKELY AND A CHANCE OF
THUNDERSTORMS.
THURSDAY...AREAS OF MVFR WITH SHOWERS LIKELY.
FRIDAY...VFR/MVFR WITH A CHANCE OF SHOWERS.
&&
.MARINE...
HIGH PRESSURE WILL DRIFT OFF THE NEW ENGLAND COAST TODAY AS LOW
PRESSURE MOVES SLOWLY FROM THE CENTRAL PLAINS TO THE WESTERN LAKES
BY WEDNESDAY. SOUTHERLY WINDS WILL INCREASE AHEAD OF THE LOW
TODAY...BUT CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY
CRITERIA THROUGH TUESDAY. SOUTHERLY WINDS WILL INCREASE FURTHER ON
TUESDAY NIGHT AND MAY BRING SMALL CRAFT ADVISORY LEVEL WINDS...
ALTHOUGH THE OFFSHORE WIND COMPONENT WILL KEEP THE GREATER WAVE
ACTION IN CANADA.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TMA
NEAR TERM...TMA
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...TMA
MARINE...TMA
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
955 AM EDT MON OCT 13 2014
.SYNOPSIS...
COOL HIGH PRESSURE ACROSS THE MID-ATLANTIC WILL GRADUALLY RELAX
ITS INFLUENCE ON OUR WEATHER TODAY AS SOUTHERLY FLOW INCREASES IN
ADVANCE OF A DEEPENING TROUGH OF LOW PRESSURE ACROSS THE CENTRAL
UNITED STATES. THIS TROUGH AND A STRONG SURFACE COLD FRONT WILL
MOVE ACROSS THE AREA TUESDAY NIGHT AND WEDNESDAY WITH THE
POTENTIAL FOR HIGH WINDS...HEAVY RAIN...AND POSSIBLY STRONG TO
SEVERE THUNDERSTORMS. UNSETTLED WEATHER WITH SHOWERS WILL CONTINUE
INTO THURSDAY AS THE UPPER LOW SLOWLY LIFTS OUT OF THE REGION.
IMPROVING WEATHER CONDITIONS ARE EXPECTED FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 945 AM EDT MONDAY...
ONLY SOME VERY LIGHT PRECIPITATION REMAINS ACROSS THE REGION
CURRENTLY. LIGHT AMOUNTS WERE ALONG THE CREST OF THE BLUE
RIDGE...AND A SMALL AREA WAS HEADING NORTH OF BLACKSBURG...ALONG
THE WV/VA BORDER. HRRR AND RNK-WRF ARW SOLUTIONS OFFER VERY LITTLE
IN THE WAY OF PRECIPITATION THE REMAINDER OF THE DAY.
HOWEVER...THAT VALUE IS NOT ZERO. WILL CONTINUE TO HAVE A FORECAST
THAT REFLECTS SLIGHT TO SLIGHT CHANCE POPS DURING THE AFTERNOON
HOURS WITH THE BEST FOCUS STILL ALONG THE SLOPES OF THE BLUE
RIDGE. WHILE THE TRAJECTORY ANGLE IS NOT THE BEST FOR
UPSLOPE...AS 850 MB WINDS INCREASE...EVEN A COMPONENT TO UPSLOPE
WILL HELP MAINTAIN SOME LIGHT PRECIPITATION IN AT LEAST THIS
REGION.
FORECAST SURFACE BASED LIFTED INDICES AND CAPE VALUES OFFER A
SOLUTION THAT ALLOWS FOR THE POTENTIAL OF ISOLATED STORMS ALONG
THE FAR WESTERN PARTS OF THE REGION...AND ALSO THE FAR
SOUTHEASTERN PARTS OF THE REGION. HAVE RE-INTRODUCED THIS
POTENTIAL DURING THE AFTERNOON HOURS ACROSS THESE REGIONS.
HOW QUICKLY THE WEDGE ERODES STILL IS A BIG QUESTION FOR TODAY.
HAVE NOT MADE ANY NOTABLE ADJUSTMENTS TO THE FORECAST REGARDING
THIS IN TERMS OF CLOUDS AND TEMPERATURES GIVEN NO ANOMALIES AT
THIS POINT TO SUGGEST THE FORECAST WILL NOT BE ON TRACK.
AS OF 400 AM EDT MONDAY...
THE NEXT 24 HOURS WILL BE PROVERBIAL CALM BEFORE THE STORM AS WE
AWAIT THE APPROACH OF THE INTENSE SYSTEM DEVELOPING OVER THE
CENTRAL U.S. MODELS ARE IN VERY CLOSE AGREEMENT ON THE DEVELOPMENT
OF A CUT-OFF UPPER LOW OVER THE SOUTHERN PLAINS TODAY AND THEN
KICKING IT EASTWARD INTO THE MID-MISSISSIPPI VALLEY BY 12Z
TUESDAY. A STRONG (591 DM) UPPER RIDGE WILL BE POSITIONED OVER THE
SOUTHEAST ATLANTIC COAST WHICH ALSO PLAY A ROLE IN PREVENTING THE
RAPID EASTWARD SHIFT OF THE UPPER TROUGH AND ENHANCING THE MOIST
ATLANTIC AND GULF INFLOW AHEAD OF THE FRONT. THE SURFACE HIGH
ALONG THE NEW ENGLAND COAST HAT HAS BEEN RESPONSIBLE FOR THE COOL-
AIR DAMMING OVER THE WEEKEND WILL BE SLOWLY DRIFTING EAST TODAY
ALLOWING FOR WINDS TO SHIFT TO SOUTHERLY THROUGH THE DAY TODAY
ERODING THE LOW CLOUDS AND DRIZZLE. HOW QUICKLY THIS WILL OCCUR
TODAY IS ALWAYS A TRICKY ASPECT OF FORECASTING IN THIS AREA WITH
SKY COVER AND HENCE HIGH TEMPERATURES RIDING ON THE OUTCOME.
PICKED A MODEL BLEND FOR HIGH TEMPS BUT EDGED TOWARD SOMEWHAT
SLOWER EROSION WHICH RESULTS IN HIGHS RANGING FROM UPPER 60S NW TO
MID-70S SE AND ALSO FAR WEST WHERE THE WEDGE WILL ERODE MOST
QUICKLY UNDER THE INCREASING SOUTHERLY FLOW. H85 WINDS IN THAT
SAME FAR WESTERN AREA (MAINLY TAZEWELL...SMYTH..MERCER COUNTIES)
WILL BE INCREASING FROM NEAR 25 KT EARLY THIS MORNING TO THE 45-50
KT RANGE BY 12Z TUESDAY WITH SOME OF THIS WINDS MIXING DOWN DURING
THE 06-12Z PERIOD. STRONGEST WINDS LIKELY TO BE BEYOND THE 12Z
CUT-OFF FOR THIS FORECAST PERIOD WHEN A WIND ADVISORY MAY BE
NEEDED. SCATTERED SHOWERS STILL POSSIBLE TODAY AS THE AIR MASS
REMAINS QUITE MOIST AND ANY WEAK IMPULSES WILL BE CAPABLE OF
GENERATING SOME SHOWER ACTIVITY.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
AS OF 400 AM EDT MONDAY...
MODELS CONTINUE TO MAKE ADJUSTMENTS TO TIMING OF THE INTENSE
UPPER-LEVEL LOW/TROUGH SLATED TO DEVELOP TODAY ACROSS THE
SOUTHERN/CENTRAL PLAINS...THEN SPREAD EASTWARD INTO TUE. EACH
MODEL RUN FOR ALL MODELS CONTINUE TO SLOW THE ARRIVAL OF THE MAIN
LINE OF INTENSE CONVECTION INTO OUR CWA ASSOCIATED WITH THIS
SYSTEM...LIKELY OWING TO THE IMPRESSIVE DIGGING/DEVELOPMENT OF THE
SYSTEM IN RESPONSE TO A 125+KT UPPER JET AND 60-70KT LLJ. IN
ESSENCE...THE MAIN LINE OF CONVECTION ASSOCIATED WITH THIS SYSTEM
IS NEARLY 36 HOURS SLOWER THAN WHAT WAS PROGGED TWO DAYS AGO AT
THIS TIME. NOW...INSTEAD OF A 12Z TUE TIME FRAME...WE ARE LOOKING
AT A 12Z WED TO 00Z THU TIME FRAME FOR THE MAIN EFFECTS.
THUS FOR TUE...THE WEDGE WILL BEGIN TO FINALLY ERODE...BUT AGAIN
NOT LIKELY AS QUICKLY AS THE MODELS WOULD SUGGEST. PERSISTENT
UPSLOPE AND INCREASING SOUTHEAST SFC FLOW WILL RESULT IN A
CONTINUATION OF SPOTTY LIGHT RAIN SHOWERS...ESPECIALLY EAST OF THE
ALLEGHANY FRONT AND ALONG UPSLOPE AREAS OF THE BLUE RIDGE. THE
MAIN DIFFERENCE BETWEEN MON AND TUE...HOWEVER...WILL BE THAT AS
THE TROUGH DEEPENS IN THE CENTRAL U.S...AN UPPER RIDGE WILL
BRIEFLY AMPLIFY THROUGH THE SE STATES INTO NC/VA. THIS WILL PUT
MUCH OF THE CWA...EAST OF THE ALLEGHANY FRONT...IN A WARM SECTOR
WHICH SHOULD REDUCE COVERAGE OF PRECIPITATION WITH INCREASING
SUBSIDENCE ALOFT. HOWEVER...ANY PERSISTENCE OF THE WEDGE
UNDERNEATH THE UPPER HIGH WILL PROMOTE CONTINUATION OF UPSLOPE
CLOUDS AND LIGHT -SHRA AS NOTED. THUS...HAVE MAINTAINED HIGH CHC
TO LOW LIKELY POPS WEST OF THE BLUE RIDGE. AS THE DAY
PROGRESSES...UPPER SUPPORT WILL BECOME INCREASINGLY
FAVORABLE...ESPECIALLY IN WESTERN AREAS...AND INSTABILITY WILL
BEGIN TO SUPPORT THE MENTION OF TSRA WEST OF I-77 BY LATE
AFTERNOON/EVENING.
CATEGORICAL POPS ARE IN ORDER FROM WEST TO EAST ACROSS THE REGION
BETWEEN 00Z WED AND 18Z WED WITH A SCENARIO OF A VERY SLOWLY
MOVING NEARLY MERIDIONAL OR SOUTH-NORTH ORIENTED NARROW BAND OF
INTENSE CONVECTION TRANSLATING SLOWLY ACROSS THE REGION AS THE
UPPER LOW BECOMES INCREASINGLY BAROTROPIC. IN FACT...IT COULD TAKE
UNTIL LATE WED FOR THE CONVECTION TO REACH EASTERN VA...SO HAVE
THE PERIOD OF CATEGORICAL POPS A GOOD 12 HOURS FROM THAT PREVIOUSLY
INDICATED. INSTABILITY REMAINS MARGINAL...BUT THE VERY STRONG LLJ
AND PROGGED SHEAR ALONG WITH CONVECTIVE MODE SUGGEST A QLCS IS
MOST PROBABLE WITH THIS SYSTEM. THIS WILL YIELD MARGINAL AMOUNTS
OF LIGHTNING...BUT POSSIBLE BOWING SEGMENTS WHICH CAN RESULT IN
LOCALIZED AREAS OF DAMAGING WINDS AND POSSIBLY EVEN AN ISOLATED
TORNADO. SPC HAS UPGRADED MUCH OF SW VA INTO A SLIGHT RISK THROUGH
THIS PERIOD...WITH A 5 PERCENT RISK FOR THE REMAINDER OF THE CWA.
THE MAIN THREAT FOR SEVERE WILL BE WITH THE STRONG LLJ TUE
NIGHT/EARLY WED...WITH LESS THREAT FURTHER EAST AS THE JET LIFTS
NORTH OUT OF THE REGION WITH THE UPPER LOW CUTTING OFF AND
BECOMING INCREASINGLY BAROTROPIC.
HEAVY RAIN WILL ALSO BE A THREAT WITH ANY TRAINING OF ECHOES
WITHIN THE SOUTH-NORTH ORIENTED BAND...ESPECIALLY CONSIDERING MUCH
PARTS OF THE CWA...ESPECIALLY WEST OF THE BLUE RIDGE...HAVE SEEN
1-2 INCHES OF RAIN IN THE PAST FEW DAYS. PWATS ARE WELL ABOVE
SEASONAL NORMALS IN THE 1.5+ RANGE AS THE CORE OF THE EVENT MOVES
THROUGH. THE FLOOD/FLASH FLOOD THREAT IS ADDRESSED FURTHER IN THE
HYDRO SECTION BELOW.
ANOTHER THREAT WITH THIS SYSTEM WILL BE STRONG WIND GUSTS IN THE
USUAL FAVORED AREAS OF SOUTHEAST WV AND SOUTHWEST VA AS THE LLJ
TRANSLATES THROUGH THE REGION. GIVEN THE DELAYED TIMING OF THIS
TO AFT 12Z TUE WITH A SLOWER ARRIVAL OF THE UPPER LOW/STRONG LLJ
THE POTENTIAL FOR A HIGH WIND WATCH/WIND ADVISORY WOULD BE DELAYED
UNTIL 3RD PERIOD. FURTHERMORE...MODELS HAVE SHOWN A RELUCTANCE TO
BRING POTENTIAL WINDS GUSTS OF 40-50KTS DOWN TO THE SFC. FEEL THAT
A WIND ADVISORY WILL MOST CERTAINLY BE WARRANTED AND WIND GUSTS
FOR A BRIEF PERIOD MAY REACH HIGH WIND WARNING CRITERIA IN PARTS
OF MERCER AND TAZEWELL COUNTIES. HOWEVER...NO OTHER OFFICES ARE ON
BOARD WITH A WATCH AND TOO FAR OUT FOR AN ADVISORY...SO NO NPW
WILL BE ISSUED AT THIS POINT. AS WITH THE SEVERE THREAT...WILL
CONTINUE TO HIGHLIGHT THE THREAT IN THE HWO.
TEMPERATURES REMAIN PROBLEMATIC...FIRST BECAUSE OF LINGERING
EFFECTS OF THE WEDGE AND THEREAFTER BECAUSE OF THE CLOSED...COLD
CORE SLOW MOVING UPPER LOW...CYCLONIC FLOW...AND POTENTIALLY
HIGHLY VARIABLE AMOUNTS OF SUNSHINE FROM WEST OF THE MOUNTAINS TO
THE PIEDMONT. HAVE LEANED TOWARD A MODEL BLEND THROUGH THE PERIOD
AS OPPOSED TO HINGING THE TEMPERATURES ON ANY ONE MODEL. TUE
SHOULD YIELD NEAR NORMAL TEMPS WEST TO SLIGHTLY ABOVE NORMAL
EAST...GIVEN EROSION OF THE WEDGE AND STRONG SOUTHERLY FLOW. WED
SHOULD ALSO YIELD NEAR MAX TEMPS AND WELL ABOVE NORMAL MIN
TEMPS...AGAIN PRIMARILY BECAUSE OF STRONG SOUTHERLY FLOW AND
DEWPOINTS INTO THE 60S EARLY WED...WELL ABOVE NORMAL FOR MID-
OCTOBER. THU...SHOULD SEE SLIGHTLY COOLER TEMPS...ESPECIALLY WEST
OF THE BLUE RIDGE WHERE CLOUDS AND SCT SHOWERS ARE EXPECTED.
AGAIN...NO BELOW FREEZING TEMPERATURES ARE EXPECTED EVEN AFTER THE
FRONTAL PASSAGE WITH 850MB TEMPS BOTTOMING OUT IN THE +4 TO +6C
RANGE.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 430 AM EDT MONDAY...
THE REGION WILL REMAIN UNDER THE INFLUENCE OF THE DEEP CLOSED
UPPER LOW THROUGH THE LATER HALF OF THE WEEK...FINALLY LIFTING OUT
FRI-SAT. SCT SHOWERS WILL PERSIST UNDER/NEAR THE UPPER LOW WITH A
NOTABLE DIURNAL INCREASE AS DAYTIME HEATING CREATES RELATIVELY
STEEP LAPSE RATES UNDER THE COLD CORE LOW. THE BEST CHANCE FOR
SHOWERS WILL BE WEST OF THE BLUE RIDGE. A HEALTHY SHORT WAVE IS
PROGGED TO FINALLY LIFT THE UPPER LOW OUT THU AFTERNOON...BUT IN
SO DOING WILL LIKELY BRING THE BEST COVERAGE OF SHOWERS TO THE
REGION...EVEN INTO THE PIEDMONT.
FOR THE WEEKEND...FINALLY SOME IMPROVING CONDITIONS INDICATED WITH
GREATER POTENTIAL FOR SUNSHINE...EVEN ACROSS THE MOUNTAINS. MAINLY
DRY WEATHER IS EXPECTED FOR THE REST OF THE LONG RANGE PERIOD WITH
NO SIGNIFICANT WEATHER SYSTEMS EXPECTED TO IMPACT THE AREA UNTIL
EARLY NEXT WEEK. MODERATING TEMPERATURES ARE EXPECTED UNDER A
WEAK WARM ADVECTION PATTERN ON FRIDAY INTO SATURDAY BEFORE NEXT
UPSTREAM SHORT WAVE TROF SCOOTS RAPIDLY SOUTHEAST OUT OF NORTHERN
PLAINS AND INTO NEW ENGLAND LATER SATURDAY NIGHT INTO SUNDAY.
BEST DYNAMICS AND MOISTURE WITH THIS SYSTEM EXPECTED TO REMAIN WELL
TO THE NORTHWEST OF THE BLACKSBURG FORECAST AREA...SO OTHER THAN A
SLIGHT INCREASE IN MID AND HIGH LEVEL CLOUDS...ONLY SENSIBLE IMPACT
WILL BE FOR A SLIGHT REINFORCEMENT OF COOLER AIR WITH PASSAGE OF DRY
COOL FRONT...AND POSSIBLY SOME ISOLATED-WIDELY SCATTERED POST
FRONTAL UPSLOPE SHOWERS REDEVELOPING ACROSS THE WESTERN FLANKS OF
THE APPALACHIANS IN SOUTHEASTERN WEST VIRGINIA...MOST NOTABLY IN
WESTERN GREENBRIER COUNTY.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
AS OF 630 AM EDT MONDAY...
VARIABLE FLIGHT CONDITIONS LIKELY TO BE THE RULE TODAY AT THE
TERMINALS AS DEPARTING HIGH PRESSURE STRUGGLES TO MAINTAIN
THE LOW CLOUDS AND EASTERLY FLOW WHILE THE TROUGH DEVELOPING
OUT WEST BRINGS INCREASING SOUTHERLY FLOW ALOFT TRYING TO MIX
DOWN TO THE SURFACE AND SCOUR OUT THE LOW CLOUDS. SHOULD SEE VERY
SLOW IMPROVEMENT IN CIGS/VBSYS AS THIS OCCURS TODAY. UNLIKELY
TO SEE MUCH IN THE WAY OF VFR BUT AT LEAST MVFR BY LATER IN THE
DAY OR EVENING. ANY PARTIAL CLEARING THAT TAKES PLACE LATE TODAY
OR OVERNIGHT LIKELY TO BRIEF AS EXTENSIVE CLOUDINESS FROM THE
CENTRAL U.S. SYSTEM WILL BE EDGING INTO THE WESTERN PORTIONS OF
THE AREA BY THAT TIME...WHICH MAY ACT TO INHIBIT FOG DEVELOPMENT
TOWARD MORNING.
EXTENDED AVIATION DISCUSSION...
TUESDAY INTO TUESDAY NIGHT A VERY STRONG NEGATIVELY TILTED UPPER
TROUGH WILL APPROACH AND MOVE THROUGH THE REGION. LOOK FOR A
SOUTHERLY 850 MB JET TO REACH 50 TO 70 KTS IN ADVANCE OF THE
SYSTEM. STRONG THUNDERSTORMS WITH PLENTY OF PRECIPITATION IS
EXPECTED IN ADVANCE AND CONCURRENT WITH THE FRONTAL PASSAGE LATE
TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING.
ON WEDNESDAY...THE FRONT WILL EXIT THE REGION BUT NORTHWEST FLOW
BEHIND THE SYSTEM WILL KEEP UPSLOPE CLOUDS AND RAIN SHOWERS ACROSS
SOUTHEAST WEST VIRGINIA...SOUTH INTO THE NORTHERN MOUNTAINS OF
NORTH CAROLINA THROUGH THURSDAY AS THE CENTER OF THE PARENT UPPER
LOW SETTLES OVER PENNSYLVANIA.
BY FRIDAY...THE PRESSURE GRADIENT WILL SLACKEN AS WE TRANSITION
INTO A MORE ZONAL PATTERN.
&&
.HYDROLOGY...
AS OF 400 AM EDT MONDAY...
THE UPCOMING EVENT WILL HAVE A SIGNIFICANT HYDRO COMPONENT WITH
HEAVY RAINFALL EXPECTED ACROSS ALL RIVER BASINS MAINLY AFTER 12Z
TUESDAY AND PERSISTING INTO EARLY THURSDAY. QPF FROM HPC DURING
THIS PERIOD IS GENERALLY IN THE 2 TO 3 INCH RANGE WITH THE TYPICAL
TERRAIN ENHANCEMENTS. GEFS AND NAEFS ENSEMBLE PRECIPITATION
FORECASTS FROM THE VARIOUS RFCS STILL SHOWING CONSIDERABLE SPREAD
IN THE QPF WITH ANYWHERE FROM 1 TO 5 INCHES IN NEARLY ALL BASINS
BUT SOLUTIONS CLUSTERING MAINLY IN THE 2 TO 2.5 INCH RANGE. THE
RIVER FORECAST ENSEMBLES RESULTING FROM THIS QPF GENERATE A LOT OF
FORECASTS NEAR OR JUST BELOW ACTION STAGE WITH A FEW MEMBERS
REACHING MINOR FLOOD STAGE AND MAYBE ONE OR TWO OUTLIERS AT
MODERATE FLOOD STAGE. SO IT DOES NOT LOOK LIKE A VERY SERIOUS
RIVER FLOOD EVENT AT THIS POINT BUT CERTAINLY WILL BE WATCHED
CLOSELY. ALSO A FLASH FLOOD THREAT TO CONSIDER AS PWATS REACH 2 TO
3 STANDARD DEVIATIONS ABOVE MID-OCTOBER KRNK RAOB CLIMATOLOGY BY
WEDNESDAY MORNING RANGING FROM 1.5 TO 1.7 INCHES AT KRNK AND
SOMEWHAT HIGHER AT ROANOKE. WITH THE WIDESPREAD 2 TO 3 INCH
RAINFALL AND EMBEDDED CONVECTION THERE WILL LIKELY BE ISOLATED 4
TO 5 INCH AMOUNTS ACROSS A FEW SMALL BASINS AND POCKETS OF RAPID
RESPONSE FLOODING SEEM TO BE A REASONABLE BET. HPC CURRENTLY
SHOWING A SLIGHT RISK OF EXCESSIVE RAINFALL IN EXCESS OF FLASH
FLOOD GUIDANCE IN THE FAR WESTERN CWA BY 12Z TUE AND FOR MOST THE
REMAINDER 12Z TUE TO 12Z WED. AN ADDITIONAL FACTOR IN THE FLOOD
POTENTIAL IS THE LOW FLASH FLOOD GUIDANCE VALUES RESULTING FROM
RAINFALL SO FAR IN OCTOBER WHICH HAS REACHED 4 TO 6 INCHES IN
PARTS OF THE TENNESSEE AND NEW RIVER BASINS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...PC
NEAR TERM...DS/PC
SHORT TERM...RAB
LONG TERM...RAB/WERT
AVIATION...PC
HYDROLOGY...PC
AREA FORECAST DISCUSSION
NWS NEW YORK NY
611 PM EDT MON OCT 13 2014
.SYNOPSIS...
HIGH PRESSURE DRIFTS EAST THROUGH TUESDAY. A SLOW MOVING FRONTAL
SYSTEM APPROACHES FOR THE MID TO LATE WEEK PERIOD...PASSING EAST
BY THE END OF THE WEEK. A SERIES OF WEAK FRONTS THEN PASS THROUGH
NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
CLOSED LOW PRESSURE ALOFT OVER THE MIDDLE OF THE COUNTRY WILL SLOWLY
LIFT NORTHEAST TONIGHT. THIS FULL LATITUDE TROUGH WILL HELP BUILD
THE EAST COAST/WESTERN ATLANTIC RIDGE.
AT THE SURFACE...HIGH PRESSURE DRIFTS EAST WITH A LOW LEVEL S/SE
FLOW SETTING UP ACROSS THE REGION AHEAD OF AN APPROACHING WEAK
WARM FRONT.
THIS MOIST LOW-LEVEL S/SE FLOW AND WAA TO THE NORTH OF THE WARM
FRONT IS RESULTING IN STRATUS DEVELOPMENT THIS EVENING
ACCOMPANIED BY ENOUGH LIFT IN THE LOW LEVELS FOR AREAS OF DRIZZLE
INTO LATE TONIGHT. IN ADDITION...WEAK MID LEVEL WAA COULD PRODUCE
A LIGHT SHOWER. ANY PRECIPITATION IS EXPECTED TO BE LIGHT.
THE SOUTH WINDS AND CLOUD COVER WILL RESULT IN A MILD NIGHT WITH LOW
TEMPERATURES IN THE 50S TO AROUND 60 ACROSS NYC METRO. THIS IS ABOUT
10 DEGREES ABOVE CLIMATOLOGY NORMALS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
MODELS REMAIN IN GENERAL AGREEMENT ON OVERALL FEATURES IN THIS
HIGHLY AMPLIFIED PATTERN. CLOSED UPPER LOW EVER SO SLOWLY MOVES
EAST. RIDGE AXIS TRACKS EAST...SETTING UP A DEEP SOUTHERLY FLOW
ALONG THE EAST COAST. PER NAM/GFS...HIGH PRESSURE OVER THE
WESTERN ATLANTIC SLIDES EAST AS LOW PRESSURE DRIFTS ACROSS
ILLINOIS AND INTO INDIANA THROUGH THIS TIME FRAME. PERSISTENT
SOUTH FLOW BETWEEN THESE TWO SYSTEMS WILL ADVECT A HIGH AMOUNT OF
MOISTURE NORTHWARD.
ON TUESDAY...SOME CLEARING IS FORECAST IN THE AFTERNOON AS THE MID
LEVEL WARM ADVECTION PASSES TO THE NORTH AND EAST. A STRAY SHOWER
NORTH AND WEST OF NYC IS NOT OUT OF THE QUESTION IN THE AFTERNOON
WITH SOME WEAK INSTABILITY DEVELOPING. HIGH TEMPS ON TUESDAY WILL BE
IN THE LOWER TO MIDDLE 70S...AND EVEN A BIT HIGHER ACROSS PARTS OF
THE NYC METRO. THESE READINGS ARE ONLY TEMPERED BY PERSISTENT S/SE
FLOW OFF THE MIDDLE 60 DEGREE WATERS.
FOR TUESDAY NIGHT...LOW CLOUDS AND FOG ALONG WITH AREAS OF LIGHT
RAIN OR DRIZZLE IS EXPECTED AS THE BOUNDARY LAYER SATURATES. TEMPS
ARE EXPECTED TO BE VERY WARM FOR THIS TIME OF YEAR. OVERNIGHT LOWS
MAY BE 15 DEGREES ABOVE SEASONAL NORMS...60S THROUGHOUT.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
THERE IS NOW DECENT AGREEMENT AMONG THE GLOBAL MODELS REGARDING THE
TIMING OF THE MID-LATE WEEK STORM SYSTEM. CMC AND GFS HAVE SETTLED
CLOSER TO THE STRONGER CLOSED 500 MB LOW/LESS PROGRESSIVE ECMWF
SOLUTION THAT IT HAD BEEN SHOWING SINCE LATE LAST WEEK.
AT THE SURFACE...A TRIPLE POINT LOW PASSES OVER OR NEARBY THE TRI
STATE AREA...PROBABLY SOMETIME DURING THURSDAY AFTERNOON OR EVENING.
WITH THIS SYSTEM...PLENTY MOISTURE ENTRAINMENT FROM THE GULF AND
ATLANTIC...POSSIBLY INCLUDING SOME FROM DISTANT TROPICAL SYSTEM
GONZALO....HELP PWATS APPROACH 2 INCHES. LIFT WILL BE DEEP AS WELL
WITH A JET STREAK NEARBY...PVA...AND A LOW LEVEL JET PASSING
THROUGH. THE COMBINATION OF THESE FACTORS BRINGS THE LIKELIHOOD OF A
MODERATE RAINFALL EVENT...POTENTIALLY HEAVY. MARGINAL INSTABILITY
AND THE UPWARD FORCING WILL ALSO BRING AN ISOLATED THREAT OF
THUNDERSTORMS...ENHANCING RAINFALL TOTALS.
SO FOR WEDNESDAY...JUST LOW CHANCES OF SHOWERS FROM AROUND THE CITY
AND POINTS WEST. THE BIGGER STORY WILL BE TEMPS...WHICH...WHILE NOT
EXPECTED TO REACH RECORDS...WILL AVERAGE WELL ABOVE NORMALS AS HIGHS
REACH MAINLY MID AND UPPER 70S. SOME INLAND SPOTS PROBABLY REACH 80.
RAIN THEN BECOMES LIKELY LATE WEDNESDAY NIGHT INTO THURSDAY
MORNING...THEN ENDS WEST TO EAST LATE IN THE DAY TO THURSDAY EVENING.
THE FLOW ALOFT ON FRIDAY WILL BE ONLY SLIGHTLY CYCLONIC WITH WEAK
HIGH PRESSURE AT THE SURFACE...SO NOT EXPECTING ANY INSTABILITY
SHOWERS. WILL HOWEVER PUT IN ISOLATED AFTERNOON SHOWERS BOTH DAYS OF
THE WEEKEND AS THE FLOW ALOFT BECOMES MORE CYCLONIC. THE FLOW THEN
BECOMES LESS CYCLONIC ON MONDAY WITH A DRY FORECAST.
AFTER ABOVE-NORMAL HIGHS ON THURSDAY THROUGH SATURDAY...HIGHS RETURN
CLOSER TO NORMALS SUNDAY AND MONDAY.
&&
.AVIATION /22Z MONDAY THROUGH SATURDAY/...
OFFSHORE HIGH PRESSURE WILL KEEP A CONSISTENT SSW-SSE WIND THROUGH
THE TAF PERIOD...MAINLY NEAR 10 KT OR LESS.
FAIRLY RAPID DETERIORATION OF CIGS/VSBY HAVE BEEN NOTED ACROSS SE
PA/CENTRAL NJ THIS EVENING WITH STRATUS/DRIZZLE TO NORTH OF MID
ATLANTIC WARM FRONT. BASED ON LATEST HRRR AND RAP
SOUNDINGS...EXPECTATION IS FOR CONDS TO CONTINUE TO DETERIORATE TO
IFR ACROSS NYC METRO TERMINALS BETWEEN 23Z AND 00Z WITH STRATUS
AND DRIZZLE ACCOMPANYING THIS. THESE CONDITIONS WILL LIKELY SPREAD
TO TERMINALS N&E THROUGH THE EVENING.
GRADUAL IMPROVEMENT TO MVFR TUESDAY MORNING WITH A SCATTERING OF
THESE LOWER CIGS EXPECTED BY EARLY TO MID TUESDAY AFTERNOON.
FORECAST CONFIDENCE IS MODERATE FOR CATEGORY AND HIGH FOR WINDS.
UNCERTAINTY IN CATEGORY WITH THE TIMING OF MVFR WHICH COULD VARY BY
2-4 HOURS.
...NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: PREVAILING IFR TIMING COULD BE OFF BY 1-2
HOURS.
KLGA FCSTER COMMENTS: PREVAILING IFR TIMING COULD BE OFF BY 1-2
HOURS.
KEWR FCSTER COMMENTS: PREVAILING IFR TIMING COULD BE OFF BY 1-2
HOURS.
KTEB FCSTER COMMENTS: PREVAILING IFR TIMING COULD BE OFF BY 1-2
HOURS.
KHPN FCSTER COMMENTS: PREVAILING IFR TIMING COULD BE OFF BY 1-2
HOURS.
KISP FCSTER COMMENTS: PREVAILING MVFR/IFR TIMING COULD BE OFF BY 1-2
HOURS.
.OUTLOOK FOR 18Z TUE THROUGH SAT...
.TUE AFTERNOON-NIGHT...VFR RETURNING MID TO LATE AFTERNOON. S-SE
WINDS 10KT. MVFR OR LOWER CONDS LIKELY LATE TUE NIGHT IN STRATUS
AND POSSIBLY FOG.
.WED...MVFR OR LOWER STRATUS/FOG LIKELY IN MORNING. INCREASING
CHANCE OF SHOWERS BY AFTERNOON/NIGHTTIME WITH MVFR CONDS. S-SE
WINDS 10-15KT. GUSTS TO 25 KT POSSIBLE.
.THU-THU NIGHT...MVFR CONDS LIKELY...IFR CONDS POSSIBLE IN
SHOWERS. SE WINDS 15G25KT. LLWS POSSIBLE.
.FRI...VFR LIKELY. WSW WINDS 10-15G20KT.
.SAT...MAINLY VFR.
&&
.MARINE...
THE WATERS WILL REMAIN BETWEEN HIGH PRESSURE TO THE EAST AND LOW
PRESSURE WELL TO THE WEST THROUGH TUESDAY. AS A RESULT...PERSISTENT
SOUTH TO SOUTHEAST WINDS ARE ANTICIPATED ACROSS THE WATERS.
FOR THE SHELTERED WATERS AROUND LONG ISLAND...SUB SCA CONDITIONS ARE
ANTICIPATED. FOR THE OCEAN WATERS...SEAS DUE TO SE SWELLS MAY
APPROACH 5 FEET AND WILL NEED TO BE WATCHED. FOR NOW...NO HEADLINES
WILL BE POSTED AND WILL CAP SEAS AT 4 FT.
SE WINDS INCREASE AHEAD OF LOW PRESSURE...WHICH WILL PROBABLY PASSES
TO THE NW SOMETIME ON THURSDAY WITH A WIND SHIFT TO THE SW THURSDAY
NIGHT INTO FRIDAY. OCEAN SEAS THEREFORE BUILD TO SCA LEVELS
WEDNESDAY AFTERNOON INTO EVENING...AND REMAIN AT ADVISORY LEVELS
THROUGH THE REST OF THE FORECAST PERIOD. THIS IS IN PART DUE TO
POTENTIAL SWELL CONTRIBUTION FROM DISTANT TROPICAL SYSTEM GONZALO.
FOR THE OTHER WATERS...A FEW GUSTS TO 25 KT COULD BE POSSIBLE LATE
WEDNESDAY NIGHT AND THURSDAY.
&&
.HYDROLOGY...
MAINLY DRY CONDITIONS ARE ANTICIPATED THROUGH TUESDAY. ONLY SPOTTY
LIGHT SHOWERS OR SPRINKLES ARE FORECAST AT THIS TIME.
RAINFALL AMOUNTS OF ONE AND A HALF TO TWO INCHES IS EXPECTED
WEDNESDAY NIGHT INTO THURSDAY. LOCALLY HIGHER AMOUNTS ARE POSSIBLE.
RAINFALL WILL POTENTIALLY BE HEAVY AT TIMES LATE WEDNESDAY NIGHT AND
THURSDAY. RIGHT NOW IT LOOKS LIKE PRIMARILY MINOR SMALL
STREAM/URBANIZED FLOODING WILL BE POSSIBLE.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JC/PW
NEAR TERM...PW/NV
SHORT TERM...PW
LONG TERM...JC
AVIATION...NV
MARINE...JC/PW
HYDROLOGY...JC/PW
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1247 PM EDT MON OCT 13 2014
.SYNOPSIS...
HIGH PRESSURE CENTERED OFF THE SOUTHEAST NEW ENGLAND COAST WILL
CONTINUE TO MOVE SLOWLY OUT TO SEA THROUGH TONIGHT AND TUESDAY. A
COLD FRONT IS FORECAST TO APPROACH FROM THE WEST ON WEDNESDAY, AND
IT SHOULD PASS THROUGH OUR REGION ON THURSDAY. HIGH PRESSURE IS
EXPECTED TO NOSE INTO OUR AREA FROM THE SOUTHWEST FOR FRIDAY.
ANOTHER COLD FRONT FROM THE NORTHWEST IS ANTICIPATED TO ARRIVE
OVER THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WITH THE EARLY AFTERNOON UPDATE, WE CONTINUED TO FOCUS THE MAIN
AREA OF SCATTERED SHWRS WITH SOME HIGH CHANCE POPS THROUGH
PORTIONS OF THE DELMARVA AND FAR SOUTHERN NJ BASED ON CURRENT
RADAR TRENDS AND DATA FROM THE HRRR AND RAP. AMOUNTS FROM THESE
SHOWERS SHOULD MAINLY BE A FEW HUNDREDTHS OF AN INCH OR LESS.
TOWARD LATE AFTERNOON TO EARLY EVENING, WE THEN FOCUSED SOMEWHAT
HIGHER POPS FROM THE EASTERN SHORE OF MARYLAND THROUGH PORTIONS OF
EASTERN PA, AS THERE WERE SOME HINTS IN THE RAP AND HRRR MODEL
DATA OF ISOLATED TO SCATTERED SHWRS FOR THESE AREAS. IN ADDITION,
HOURLY TEMPS AND DEWPOINTS WERE ADJUSTED THROUGH LATE AFTERNOON,
AND WE ALSO TWEAKED MAX TEMPS BY A DEGREE OR TWO, MOSTLY ACROSS
EASTERN PA.
OTHERWISE, HIGH PRESSURE AT THE SURFACE WILL REMAIN OFFSHORE OF
THE NORTHEAST STATES THROUGH TODAY, WHICH WILL KEEP A SOUTH-
SOUTHEAST FLOW ACROSS THE AREA. THIS SOUTHERLY FLOW WILL KEEP THE
LOW LEVELS MOIST, LEADING TO OVERCAST SKIES THROUGH THE DAY. THERE
IS SOME VERY WEAK LIFT MOVING THROUGH DURING THE DAY AS SOME WEAK
VORTICITY SLIDES INTO THE AREA, SO THERE COULD BE SOME ISOLATED-
SCATTERED SHOWERS THROUGH THE DAY. QPF AMOUNTS ARE LIGHT, SO ANY
RAIN SHOULD ONLY AMOUNT TO A COUPLE OF HUNDREDTHS OF AN INCH OVERALL.
WE DO NOT EXPECT MUCH IN THE WAY OF SUNSHINE TODAY, SO WE DO NOT
EXPECT A SIGNIFICANT WARMING TODAY. A BLEND OF MET/MAV MOS AND
MOSGUIDE WAS USED, WITH SLIGHTLY HIGHER EMPHASIS ON THE COOLER
MET.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
THE HIGH PRESSURE DOES NOT MOVE MUCH THROUGH TONIGHT, REMAINING
OFFSHORE OF THE NORTHEAST. THIS WILL KEEP CLOUDY SKIES AND PLENTY
OF LOW-LEVEL MOISTURE FLOWING ACROSS THE AREA. THERE WILL REMAIN A
CHANCE OF RAIN OVERNIGHT AS ANOTHER WEAK PIECE OF VORTICITY SLIDES
ACROSS THE AREA. QPF AMOUNTS REMAIN LIGHT, SO ANY RAIN SHOULD ONLY
AMOUNT TO A COUPLE OF HUNDREDTHS OF AN INCH. WITH THE AMOUNT OF
LOW-LEVEL MOISTURE, IT`S ALSO POSSIBLE WE MAY ALSO SEE SOME PATCHY
DRIZZLE OR FOG DEVELOP AFTER MIDNIGHT, ESPECIALLY FOR THE
NORTHWESTERN HALF OF THE AREA.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
A MID LEVEL RIDGE IS FORECAST TO BE LOCATED OVER THE WESTERN
NORTH ATLANTIC ON TUESDAY WITH A CUT OFF LOW CENTERED OVER THE
SAINT LOUIS VICINITY. THE LOW IS EXPECTED TO DRIFT OVER INDIANA
FOR WEDNESDAY.
WE EXPECT OUR REGION TO GET INTO THE WARM SECTOR AHEAD OF THE
SYSTEM APPROACHING FROM THE WEST FOR TUESDAY INTO WEDNESDAY.
TEMPERATURES SHOULD RISE NEAR OR A BIT ABOVE 80 DEGREES IN MUCH OF
OUR REGION DURING THE AFTERNOON HOURS ON BOTH DAYS IN THE
SOUTHEAST TO SOUTH SURFACE FLOW.
THERE IS A LOW OR SLIGHT CHANCE OF SHOWERS IN THE UPSLOPE AREAS
OF EASTERN PENNSYLVANIA ON TUESDAY AND TUESDAY NIGHT. ALSO, THE
INCREASING LOW LEVEL MOISTURE THROUGHOUT OUR REGION MAY RESULT IN
PATCHY LOW CLOUDS AND FOG FOR LATE TUESDAY NIGHT AND EARLY
WEDNESDAY MORNING.
THE MAIN AREA OF PRECIPITATION APPROACHING FROM THE WEST IS
ANTICIPATED TO MAKE SLOW PROGRESS INTO OUR REGION ON WEDNESDAY.
THE MID LEVEL LOW IS FORECAST TO LIFT OVER MICHIGAN AND LAKES
HURON AND SUPERIOR DURING THURSDAY AND THURSDAY NIGHT. THE LOW IS
EXPECTED TO PULL A NEGATIVE TILT TROUGH OVER OUR REGION ON
THURSDAY NIGHT.
WE ARE FORECASTING AN INCREASING CHANCE FOR SHOWERS ON WEDNESDAY
NIGHT WITH OUR MOST LIKELY TIME FOR PRECIPITATION BEING FROM LATE
WEDNESDAY NIGHT INTO THURSDAY. SHOWERS ARE ANTICIPATED TO LINGER
INTO THURSDAY NIGHT UNTIL THE MID LEVEL TROUGH AXIS CLEARS OUR
REGION.
WE WILL CONTINUE TO MENTION THE POTENTIAL FOR THUNDERSTORMS FOR
WEDNESDAY NIGHT INTO THURSDAY WITH THIS ROBUST SYSTEM. CONDITIONS
ARE ANTICIPATED TO BE AT LEAST MARGINALLY UNSTABLE WITH SURFACE
DEW POINTS GENERALLY IN THE LOWER AND MIDDLE 60S. ANY CONVECTION
SHOULD BE RELATIVELY LOW TOPPED. HOWEVER, ENOUGH SHEAR IS EXPECTED
TO BE PRESENT TO RESULT IN SOME ORGANIZED STORMS WITH STRONG WIND
GUSTS POSSIBLE. PRECIPITABLE WATER VALUES MAY GET UP INTO THE 1.8
INCH RANGE AND THERE COULD BE A PERIOD OF MODERATE TO HEAVY
RAINFALL.
SOME DRYING IS EXPECTED TO FOLLOW IN THE SOUTHWEST FLOW IN THE
WAKE OF THE COLD FRONT FOR FRIDAY. TEMPERATURES SHOULD BEGIN TO
DROP BACK TOWARD NEAR NORMAL LEVELS FOR MID OCTOBER.
A LONG WAVE MID LEVEL TROUGH IS ANTICIPATED TO SETTLE OVER THE
EASTERN STATES FOR NEXT WEEKEND ALONG WITH THE ARRIVAL OF AN
ASSOCIATED SURFACE COLD FRONT. THE BOUNDARY IS NOT EXPECTED TO
HAVE MUCH MOISTURE ASSOCIATED WITH IT.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
THIS AFTERNOON...MVFR CEILINGS OVERALL. THERE IS A CHANCE THAT SOME
MVFR CEILINGS IMPROVE TO VFR FOR A TIME. SOME SPRINKLES AND SHOWERS
WILL BE AROUND, AND AMENDMENTS WILL BE ISSUED IF ANY VISIBILITY
RESTRICTIONS ARE ANTICIPATED. SOUTHEASTERLY WINDS 5-8 KNOTS.
TONIGHT...MVFR CEILINGS SHOULD LOWER TO AREAS OF IFR. WHILE THERE
COULD BE A FEW SHOWERS IN THE EVENING, SOME DRIZZLE SHOULD THEN
DEVELOP OVERNIGHT ESPECIALLY NORTH AND WEST OF KPHL. AS THE MOISTURE
INCREASES, SOME FOG IS EXPECTED WITH VISIBILITIES LOCALLY LOWERING
TO IFR LATE. OUR CONFIDENCE REGARDING THE FOG IS LOWER GIVEN THE
CLOUD COVER THAT IS EXPECTED FOR MUCH OF THE AREA. SOUTH-SOUTHEAST
WINDS AROUND 5 KNOTS, BECOMING LIGHT AND VARIABLE AT MANY TERMINALS.
TUESDAY...OVERALL CONDITIONS MVFR/IFR IN THE MORNING, THEN
IMPROVEMENT TO VFR SHOULD OCCUR. A SHOWER OR SOME DRIZZLE IS
POSSIBLE MAINLY IN THE MORNING, ESPECIALLY NORTH AND WEST OF KPHL.
SOUTH-SOUTHEAST WINDS INCREASING TO AROUND 10 KNOTS WITH SOME LOCAL
AFTERNOON GUSTS UP TO 20 KNOTS.
OUTLOOK...
LATE TUESDAY NIGHT AND WEDNESDAY MORNING...CONDITIONS VARYING
BETWEEN MVFR AND VFR. LOW CLOUDS AND FOG MAY RESULT IN AREAS OF
IFR. A CHANCE OF SHOWERS, MAINLY AROUND KRDG AND KABE.
WEDNESDAY AFTERNOON...MAINLY VFR WITH A CHANCE OF SHOWERS.
WEDNESDAY NIGHT AND THURSDAY...CONDITIONS VARYING BETWEEN MVFR
AND VFR IN SHOWERS AND SCATTERED THUNDERSTORMS. THE RAIN MAY
BECOME HEAVY. IFR CONDITIONS ARE POSSIBLE AT TIMES.
THURSDAY NIGHT...A CHANCE OF SHOWERS WITH CONDITIONS FORECAST TO
IMPROVE TO ALL VFR.
FRIDAY...MAINLY VFR.
&&
.MARINE...
SUB-SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED TO CONTINUE
ACROSS THE WATERS THROUGH TONIGHT, ALTHOUGH WINDS MAY GUST AROUND
20 KNOTS LATER TODAY THROUGH TONIGHT. SEAS ARE EXPECTED TO REMAIN
AROUND 3-4 FEET THROUGH THE PERIOD.
OUTLOOK...
TUESDAY MORNING...NO MARINE HEADLINES ARE ANTICIPATED.
TUESDAY AFTERNOON THROUGH FRIDAY...A SMALL CRAFT ADVISORY MAY
BECOME NECESSARY ON OUR OCEAN WATERS WITH WAVES EXPECTED TO BUILD
TO 5 TO 7 FEET IN A PERSISTENT SOUTHEAST TO SOUTH FLOW. ALSO, WIND
GUSTS MAY APPROACH 25 KNOTS FROM WEDNESDAY AFTERNOON INTO
THURSDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...IOVINO
NEAR TERM...KLINE/ROBERTSON
SHORT TERM...ROBERTSON
LONG TERM...IOVINO
AVIATION...GORSE/IOVINO
MARINE...IOVINO/ROBERTSON
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
533 PM CDT MON OCT 13 2014
.MESOSCALE DISCUSSION...
510 PM CDT
A SEGMENTED LINE OF STORMS FROM PONTIAC TO FAR SOUTHEAST IL WILL
MOVE NORTH-NORTHEAST THROUGH EARLY THIS EVENING...EVOLVING WITH THE
SYNOPTIC SCALE MOIST PLUME. WITHIN THIS OVERALL CONVECTIVE LINE
THERE HAVE BEEN A HANDFUL OF EMBEDDED MESOSCALE LINE-ECHO WAVE
PATTERNS IN CENTRAL IL...INCLUDING ONE WHICH PERSISTED FOR OVER AN
HOUR PRODUCING A REPORTED TORNADO NOT FAR FROM DECATUR. THIS
PARTICULAR CIRCULATION HAS SINCE WEAKENED...BUT FURTHER SOUTH-
SOUTHEAST THERE ARE REDEVELOPING CIRCULATIONS...AS WELL AS SOME
INFLOW KINKS IN STORM SEGMENTS THAT WILL BEAR WATCHING.
MODIFIED RAP SOUNDINGS FOR NEAR GIBSON CITY...WATSEKA...AND
KANKAKEE...INDICATE SURFACE-BASED INSTABILITY OF A FEW HUNDRED
JOULES. THIS IS PRESENT THROUGH 7-8 PM AS LOW-LEVEL TEMPS AND
THETA-E ARE INCREASING AS ADVECTION DRIVES THE WARM SECTOR. THE
SOUTHEAST SURFACE FLOW UNDERNEATH A STRONG 45-55 KT LOW-LEVEL JET
SAMPLED BY AREA VAD PROFILERS WILL KEEP LOW-LEVEL SHEAR HIGH AND AT
LEAST KEEP SOME VORTICITY GENERATION POTENTIAL. IN ADDITION...LCLS
ARE LOW AT ONLY 2000-2500 FT. WHILE THE OVERALL THREAT REMAINS
ISOLATED...DEPENDING ON STORM TRENDS THE NEXT HOUR OR TWO...THE
TORNADO WATCH MAY NEED TO BE LOCALLY EXPANDED INTO NORTHWEST INDIANA.
BESIDES CIRCULATIONS...THE SEGMENTS OF STORMS COULD SIMPLY BRING
ISOLATED STRONG WINDS GUSTS. HAVE SEEN THIS FURTHER SOUTH IN THE
ILLINOIS THIS AFTERNOON AS WELL.
MTF
&&
.DISCUSSION...
258 PM CDT
THE REGION WILL BE UNDER THE INFLUENCE OF A SLOW MOVING CLOSED UPPER
LOW WHICH WILL RESULT IN WET AND ACTIVE WEATHER OVER THE NEXT FEW
DAYS.
//SHORT TERM...
TODAY AND TONIGHT...
THIS AFTERNOON...A DEEP TROUGH IS NOTED ON WATER VAPOR IMAGERY
ACROSS CENTRAL CONUS WITH A CLOSED UPPER LOW SPINNING AT THE BASE
OF THE TROUGH OVER EASTERN OKLAHOMA. SURFACE ANALYSIS SHOWS LOW
PRESSURE CENTERED OVER CENTRAL MISSOURI WITH A WARM FRONT DRAPED
ACROSS CENTRAL ILLINOIS. DEWPOINTS IN THE SOUTHERN COUNTIES OF THE
OUTLOOK AREA ALONG THE WARM FRONT HAVE RISEN INTO THE MID/UPPER
60S WHERE A FEW HUNDRED J/KG CAPE IS PRESENT. THROUGH THE
REMAINDER OF THE AFTERNOON AND EVENING...STRENGTHENING WINDS ALOFT
ARE EXPECTED WITH BOTH THE UPPER JET AND LOW LEVEL JET WHICH WILL
RESULT IN STRONG DEEP LAYER SHEAR VALUES AND STRONG MOISTURE
TRANSPORT INTO THE REGION WITH PWATS RISING TO BETWEEN 1.6 AND 1.7
INCHES BY THIS EVENING. THE SURFACE LOW WILL SLOWLY DRIFT NE OVER
THE NEXT 24 HOURS OR SO WITH WHAT SHOULD BE TWO AXIS OF HEAVY RAIN
BIFURCATING THE CWA. THE FIRST AXIS WILL BE ASSOCIATED WITH A DEEP
AND PERSISTENT AREA OF ISENTROPIC ASCENT AND STRONG MOISTURE
CONVERGENCE ON THE NOSE OF A LOW LEVEL JET WHICH WILL STRETCH FROM
ROUGHLY SOUTH CENTRAL IA INTO NORTHWEST/NORTH CENTRAL IL THEN
CENTRAL WI. PRECIPITATION INTENSITY WITH THIS AREA SHOULD PEAK
OVER NORTH CENTRAL IL THIS AFTERNOON THROUGH MID EVENING...THEN
THE BETTER FORCING WILL SHIFT NORTH INTO WISCONSIN THEREAFTER. THE
SECOND AREA OF CONCERN STRETCHES FROM FAR EAST CENTRAL IL/NW
INDIANA WHERE VERY MODEST INSTABILITY AND STRONG SHEAR WILL
SUPPORT LINEAR CONVECTION. GIVEN THE MOIST SOUNDINGS...THESE
THUNDERSTORMS ARE EXPECTED TO BE EFFICIENT RAIN PRODUCERS. WHILE
THERE IS SOME UNCERTAINTY IN THE AVAILABLE INSTABILITY...
ESPECIALLY AS WE MOVE BEYOND MOST FAVORABLE DIURNAL TIMING...THERE
IS A SEVERE WEATHER THREAT WITH THE MAIN CONCERN BEING DAMAGING
STRAIGHT LINE WINDS. ENHANCED HELICITY NEAR THE WARM FROM WILL
ALSO PROMOTE A LOW END TORNADO THREAT THIS EVENING. THE HEART OF
THE CWA INCLUDING THE CHICAGO METRO AREA MAY BE SPARED SOME OF THE
HIGHER RAINFALL TOTALS BUT STILL EXPECT PERIODS OF RAIN AND
DRIZZLE AT TIMES THROUGH THE EVENING AND OVERNIGHT HOURS.
TUESDAY THROUGH THURSDAY...
SURFACE LOW IS PROGGED TO BE OVER WEST CENTRAL ILLINOIS EARLY
TUESDAY MORNING. MID LEVEL RH FIELDS INDICATE THAT THE DRY SLOT WILL
ROTATE ACROSS THE FORECAST AREA EARLY TUESDAY. WITH THE LOSS OF THE
DEEPER MOISTURE...EXPECT PRECIP TO TAPER TO A LIGHT RAIN AND DRIZZLE
FOR A PERIOD EARLY TUESDAY...THEN TUESDAY NIGHT INTO WEDNESDAY THE
DEFORMATION ZONE WILL SLOWLY TRANSLATE ACROSS THE AREA WITH PRECIP
PICKING UP AGAIN. BY WEDNESDAY MORNING...THE SURFACE LOW IS EXPECTED
TO BE IN NORTHWEST INDIANA. DESPITE HEIGHTS BUILDING ALOFT AND
WARMING/DRYING IN THE MID/UPPER LEVELS...LOW LEVEL FLOW WILL REMAIN
CYCLONIC WITH NEAR SATURATED CONDITIONS SUPPORTING CONTINUED
POSSIBILITY FOR DRIZZLE AND LIGHT RAIN WEDNESDAY AND WEDNESDAY NIGHT
BEHIND THE DEPARTING LOW. LOW LEVEL FLOW STARTS TO BECOME
ANTICYCLONIC ON THURSDAY AND SHOULD ALLOW SKIES TO SCATTER OUT AND
FOR PRECIP TO END.
//LONG TERM...
FRIDAY THROUGH MONDAY...
AN UPPER LEVEL DISTURBANCE EMANATING FROM THE PACIFIC NORTHWEST IS
PROGGED TO MERGE WITH THE AFOREMENTIONED SLOW MOVING UPPER LOW
ACROSS THE GREAT LAKES REGION ON THURSDAY...AND EVENTUALLY DRIVING A
REINFORCING COLD FRONT ACROSS THE AREA ON SATURDAY. SOUNDINGS
INDICATE THE AIRMASS IS PRETTY DRY OUT AHEAD OF THE FRONT SO CHANCE
FOR PRECIP ARE PRETTY LOW. HIGH PRESSURE BUILDS IN BEHIND THE FRONT
AND SHOULD RESULT IN CONTINUED COOL BUT DRIER WEATHER REST OF THE
WEEKEND INTO EARLY NEXT WEEK.
BMD
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* PERIODS OF SHRA/POSSIBLE TSRA THROUGH THIS EVENING WITH
PREVAILING MVFR
* SOUTHEASTERLY UP TO 20KT BECMG A BIT MORE SOUTHERLY WITH GUSTS
20-25KT
* WINDS SHIFTING TO NELY TOMORROW AFTERNOON
IZZI
//DISCUSSION...UPDATED 18Z...
COPIOUS AMOUNTS OF MOISTURE CONTINUES TO STREAM NORTH ACROSS THE
REGION AS A DEEP LOW PRESSURE SYSTEM MOVES INTO CENTRAL MISSOURI,
A WEAK WARM FRONT EXTENDS ACROSS CNTRL IL/IN FROM THE LOW...WITH
MVFR/IFR CIGS AND ISOLD SHRA NORTH OF THE BOUNDARY...WITH HIGHER
MVFR CIGS TO THE SOUTH. CIGS HAVE BEEN BOUNCING ALL OVER THE PLACE
WITH RESPECT TO BASES TODAY...AND THIS TREND WILL LIKELY CONTINUE
THROUGH MUCH OF THE REMAINDER OF THE PERIOD. SO...IN
GENERAL...HAVE LOW CONFIDENCE IN THE TIMING AND DURATION OF WHEN
BASES WILL BE VFR...MVFR OR IFR. OCNL REDUCED VISIBILITY TO 4-5SM
IN SHRA WILL ALSO BE POSSIBLE THIS AFTERNOON.
AS THE SFC LOW SLOWLY TRACKS NEWD THE WARM FRONT WILL PUSH NORTH
OF THE TERMINALS...VEERING WINDS GRADUALLY TROUGH SELY TO SLY
OVERNIGHT WHILE ALSO STRENGTHENING. GUSTS UP TO 20KT ARE LIKELY
WAS WINDS TURN SELY...AND 25KT OR HIGHER LATER TONIGHT WITH
INCREASING PRESSURE FALLS AND A STRENGTHENING PRESSURE GRADIENT
WITH THE APPROACH OF THE LOW. THERE IS EVEN A CHANCE FOR SOME
STRONGER GUSTS TONIGHT...ESPECIALLY AROUND ANY THUNDERSTORMS AS A
LOW LEVEL JET OF 50-60KT MOVES OVERHEAD AND SOME OF THIS STRONGER
WIND COULD HAVE AN OPPORTUNITY TO MIX DOWN TO THE SFC. ALSO AS THE
SFC LOW APPROACHES...WIDESPREAD SHOWERS AND THUNDERSTORMS WILL
SPREAD ACROSS THE REGION...BUT THE GREATEST CHANGE FOR ORGANIZED
THUNDERSTORMS SHOULD GENERALLY BE SOUTH OF A LINE FROM VPZ TO PNT.
SOME ISOLATED...EMBEDDED THUNDER IS POSSIBLE NORTH OF THIS
LINE...BUT WILL KEEP ANY MENTION OF THUNDER OUT OF THE
TAFS...EXCEPT FOR GYY...AS ANY TS WILL LIKELY HAVE A VERY SPARSE
COVERAGE.
FOLLOWING THE PASSAGE OF THE ASSOCIATED COLD FRONT LATE TONIGHT
AND AS THE UPPER LOW MOVES OVER CNTRL IL TOMORROW...A SLOT OF DRY
AIR WILL OVERSPREAD THE REGION...SHUTTING OFF THE HEAVIER RAIN
POTENTIAL AND SETTING UP A PERIOD OF DRIZZLE AND LOW STRATUS INTO
THE LATE MORNING HOURS TOMORROW. A WIND SHIFT TO NELY WILL TAKE
PLACE TOMORROW AS THE SFC LOW SLOWLY TRACKS ACROSS THE REGION.
CURRENTLY ANTICIPATE THAT THE WIND SHIFT WILL OCCUR AT RFD BY ARND
12-13Z TOMORROW MORNING...BUT NOT UNTIL THE LATE AFTERNOON FOR THE
CHICAGO AREA TERMINALS. THIS WILL NOT BE THE END OF THE PCPN
POTENTIAL AS MOISTURE WRAPPING AROUND THE SYSTEM WILL BRING MORE
WIDESPREAD STRATIFORM RAIN AND IFR-MVFR CIGS AT LEAST INTO
TOMORROW EVENING.
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* MEDIUM CONFINDENCE IN PRIMARILY MVFR CIGS THIS EVENING
* HIGH CONFIDENCE IN PRECIP TRENDS THIS EVENING...MEDIUM
CONFIDENCE IN PRECIP FORECAST LATE TONIGHT/TUESDAY
* MEDIUM TO HIGH CONFIDENCE IN WINDS
IZZI
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT...OCNL -SHRA. MVFR CIGS LIKELY. STRONG NORTH TO
NORTHEAST WINDS POSSIBLE.
WEDNESDAY...OCNL -SHRA. MVFR CIGS PROBABLE...SMALL CHANCE OF IFR
CIGS.
THURSDAY...SMALL CHANCE OF -SHRA...PREDOMINANTLY VFR.
FRIDAY THROUGH SUNDAY...PREDOMINANTLY VFR.
BEACHLER
&&
.MARINE...
315 PM CDT
STRONG LOW PRESSURE LIFTING OUT OF MISSOURI LATE THIS AFTERNOON
HAS A WARM SECTOR THAT IS QUICKLY MOVING NORTHWARD ACROSS ILLINOIS
AND INDIANA. THIS WILL REACH THE FAR SOUTHERN PART OF THE LAKE BY
SUNSET...LEADING TO SMALL CRAFT CRITERIA WINDS. THE WINDS MAY BE
THE STRONGEST THIS EVENING ON THE INDIANA SHORE GIVEN THE OFFSHORE
COMPONENT...WHILE THE WAVES BUILDING THE QUICKEST ON THE ILLINOIS
SHORE WITH THE ONSHORE FLOW. DENSE FOG WILL LIKELY EASE QUICKLY
OVER THE FAR SOUTHERN PART OF THE LAKE INTO EARLY THIS
EVENING WITH THIS INCREASING FLOW...AS WELL AS RAIN MOVING
OVER THE LAKE HELPING TO MIX THE MARINE LAYER.
AS THE LOW PRESSURE APPROACHES THE LAKE IT WILL SLOW AS WELL AS
GRADUALLY EXPAND. THIS MAKES IT CHALLENGING FOR WINDS AS THE WARM
FRONTAL PORTION OF THIS LOW /SEPARATING NORTHEAST WINDS FROM
SOUTHEAST/ WILL EXTEND OVER THE LAKE AND WILL GRADUALLY WEAKEN
TOO. THIS DEMARKATION IN WINDS WILL LIKELY BE ACROSS THE CENTRAL
PART OF THE LAKE DURING THE DAY TUESDAY AND THEN GRADUALLY FADE
INTO THE DAY WEDNESDAY...ALLOWING NORTHERLY WINDS TO ENVELOP
SOUTHWARD. THIS COULD HAPPEN MORE QUICKLY THOUGH WHICH WOULD LEAD
TO SMALL CRAFT CRITERIA WAVES AND POSSIBLY WINDS INTO THE ILLINOIS
NEARSHORE LATE TUESDAY INTO TUESDAY EVENING.
IN ADDITION...IT IS POSSIBLE TEMPORARY NORTHEAST GALES COULD BE
EXPERIENCED ON THE NORTHERN PART OF THE LAKE TUESDAY NORTH OF THE
WARM FRONT.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 5 AM TUESDAY.
DENSE FOG ADVISORY...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-
LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-
LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 PM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
513 PM CDT MON OCT 13 2014
.MESOSCALE DISCUSSION...
510 PM CDT
A SEGMENTED LINE OF STORMS FROM PONTIAC TO FAR SOUTHEAST IL WILL
MOVE NORTH-NORTHEAST THROUGH EARLY THIS EVENING...EVOLVING WITH THE
SYNOPTIC SCALE MOIST PLUME. WITHIN THIS OVERALL CONVECTIVE LINE
THERE HAVE BEEN A HANDFUL OF EMBEDDED MESOSCALE LINE-ECHO WAVE
PATTERNS IN CENTRAL IL...INCLUDING ONE WHICH PERSISTED FOR OVER AN
HOUR PRODUCING A REPORTED TORNADO NOT FAR FROM DECATUR. THIS
PARTICULAR CIRCULATION HAS SINCE WEAKENED...BUT FURTHER SOUTH-
SOUTHEAST THERE ARE REDEVELOPING CIRCULATIONS...AS WELL AS SOME
INFLOW KINKS IN STORM SEGMENTS THAT WILL BEAR WATCHING.
MODIFIED RAP SOUNDINGS FOR NEAR GIBSON CITY...WATSEKA...AND
KANKAKEE...INDICATE SURFACE-BASED INSTABILITY OF A FEW HUNDRED
JOULES. THIS IS PRESENT THROUGH 7-8 PM AS LOW-LEVEL TEMPS AND
THETA-E ARE INCREASING AS ADVECTION DRIVES THE WARM SECTOR. THE
SOUTHEAST SURFACE FLOW UNDERNEATH A STRONG 45-55 KT LOW-LEVEL JET
SAMPLED BY AREA VAD PROFILERS WILL KEEP LOW-LEVEL SHEAR HIGH AND AT
LEAST KEEP SOME VORTICITY GENERATION POTENTIAL. IN ADDITION...LCLS
ARE LOW AT ONLY 2000-2500 FT. WHILE THE OVERALL THREAT REMAINS
ISOLATED...DEPENDING ON STORM TRENDS THE NEXT HOUR OR TWO...THE
TORNADO WATCH MAY NEED TO BE LOCALLY EXPANDED INTO NORTHWEST INDIANA.
BESIDES CIRCULATIONS...THE SEGMENTS OF STORMS COULD SIMPLY BRING
ISOLATED STRONG WINDS GUSTS. HAVE SEEN THIS FURTHER SOUTH IN THE
ILLINOIS THIS AFTERNOON AS WELL.
MTF
&&
.DISCUSSION...
258 PM CDT
THE REGION WILL BE UNDER THE INFLUENCE OF A SLOW MOVING CLOSED UPPER
LOW WHICH WILL RESULT IN WET AND ACTIVE WEATHER OVER THE NEXT FEW
DAYS.
//SHORT TERM...
TODAY AND TONIGHT...
THIS AFTERNOON...A DEEP TROUGH IS NOTED ON WATER VAPOR IMAGERY
ACROSS CENTRAL CONUS WITH A CLOSED UPPER LOW SPINNING AT THE BASE
OF THE TROUGH OVER EASTERN OKLAHOMA. SURFACE ANALYSIS SHOWS LOW
PRESSURE CENTERED OVER CENTRAL MISSOURI WITH A WARM FRONT DRAPED
ACROSS CENTRAL ILLINOIS. DEWPOINTS IN THE SOUTHERN COUNTIES OF THE
OUTLOOK AREA ALONG THE WARM FRONT HAVE RISEN INTO THE MID/UPPER
60S WHERE A FEW HUNDRED J/KG CAPE IS PRESENT. THROUGH THE
REMAINDER OF THE AFTERNOON AND EVENING...STRENGTHENING WINDS ALOFT
ARE EXPECTED WITH BOTH THE UPPER JET AND LOW LEVEL JET WHICH WILL
RESULT IN STRONG DEEP LAYER SHEAR VALUES AND STRONG MOISTURE
TRANSPORT INTO THE REGION WITH PWATS RISING TO BETWEEN 1.6 AND 1.7
INCHES BY THIS EVENING. THE SURFACE LOW WILL SLOWLY DRIFT NE OVER
THE NEXT 24 HOURS OR SO WITH WHAT SHOULD BE TWO AXIS OF HEAVY RAIN
BIFURCATING THE CWA. THE FIRST AXIS WILL BE ASSOCIATED WITH A DEEP
AND PERSISTENT AREA OF ISENTROPIC ASCENT AND STRONG MOISTURE
CONVERGENCE ON THE NOSE OF A LOW LEVEL JET WHICH WILL STRETCH FROM
ROUGHLY SOUTH CENTRAL IA INTO NORTHWEST/NORTH CENTRAL IL THEN
CENTRAL WI. PRECIPITATION INTENSITY WITH THIS AREA SHOULD PEAK
OVER NORTH CENTRAL IL THIS AFTERNOON THROUGH MID EVENING...THEN
THE BETTER FORCING WILL SHIFT NORTH INTO WISCONSIN THEREAFTER. THE
SECOND AREA OF CONCERN STRETCHES FROM FAR EAST CENTRAL IL/NW
INDIANA WHERE VERY MODEST INSTABILITY AND STRONG SHEAR WILL
SUPPORT LINEAR CONVECTION. GIVEN THE MOIST SOUNDINGS...THESE
THUNDERSTORMS ARE EXPECTED TO BE EFFICIENT RAIN PRODUCERS. WHILE
THERE IS SOME UNCERTAINTY IN THE AVAILABLE INSTABILITY...
ESPECIALLY AS WE MOVE BEYOND MOST FAVORABLE DIURNAL TIMING...THERE
IS A SEVERE WEATHER THREAT WITH THE MAIN CONCERN BEING DAMAGING
STRAIGHT LINE WINDS. ENHANCED HELICITY NEAR THE WARM FROM WILL
ALSO PROMOTE A LOW END TORNADO THREAT THIS EVENING. THE HEART OF
THE CWA INCLUDING THE CHICAGO METRO AREA MAY BE SPARED SOME OF THE
HIGHER RAINFALL TOTALS BUT STILL EXPECT PERIODS OF RAIN AND
DRIZZLE AT TIMES THROUGH THE EVENING AND OVERNIGHT HOURS.
TUESDAY THROUGH THURSDAY...
SURFACE LOW IS PROGGED TO BE OVER WEST CENTRAL ILLINOIS EARLY
TUESDAY MORNING. MID LEVEL RH FIELDS INDICATE THAT THE DRY SLOT WILL
ROTATE ACROSS THE FORECAST AREA EARLY TUESDAY. WITH THE LOSS OF THE
DEEPER MOISTURE...EXPECT PRECIP TO TAPER TO A LIGHT RAIN AND DRIZZLE
FOR A PERIOD EARLY TUESDAY...THEN TUESDAY NIGHT INTO WEDNESDAY THE
DEFORMATION ZONE WILL SLOWLY TRANSLATE ACROSS THE AREA WITH PRECIP
PICKING UP AGAIN. BY WEDNESDAY MORNING...THE SURFACE LOW IS EXPECTED
TO BE IN NORTHWEST INDIANA. DESPITE HEIGHTS BUILDING ALOFT AND
WARMING/DRYING IN THE MID/UPPER LEVELS...LOW LEVEL FLOW WILL REMAIN
CYCLONIC WITH NEAR SATURATED CONDITIONS SUPPORTING CONTINUED
POSSIBILITY FOR DRIZZLE AND LIGHT RAIN WEDNESDAY AND WEDNESDAY NIGHT
BEHIND THE DEPARTING LOW. LOW LEVEL FLOW STARTS TO BECOME
ANTICYCLONIC ON THURSDAY AND SHOULD ALLOW SKIES TO SCATTER OUT AND
FOR PRECIP TO END.
//LONG TERM...
FRIDAY THROUGH MONDAY...
AN UPPER LEVEL DISTURBANCE EMANATING FROM THE PACIFIC NORTHWEST IS
PROGGED TO MERGE WITH THE AFOREMENTIONED SLOW MOVING UPPER LOW
ACROSS THE GREAT LAKES REGION ON THURSDAY...AND EVENTUALLY DRIVING A
REINFORCING COLD FRONT ACROSS THE AREA ON SATURDAY. SOUNDINGS
INDICATE THE AIRMASS IS PRETTY DRY OUT AHEAD OF THE FRONT SO CHANCE
FOR PRECIP ARE PRETTY LOW. HIGH PRESSURE BUILDS IN BEHIND THE FRONT
AND SHOULD RESULT IN CONTINUED COOL BUT DRIER WEATHER REST OF THE
WEEKEND INTO EARLY NEXT WEEK.
BMD
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* OCNL PERIODS MVFR/IFR CIGS AND MVFR VIS AS A STRONG STORM SYSTEM
MOVES THROUGH THE REGION.
* LIGHT WINDS SELY-ELY THROUGH ARND NOON...THEN BECMG SELY AND
INCRG TO 10-12KT.
* WINDS BECMG SELY AND INCREASING TO 12G18-20KT THROUGH THE
AFTERNOON...BECMG SLY AND INCRG TO 18G25KT OR POSSIBLY HIGHER
LATE EVENING TO LATE NIGHT TONIGHT.
* PERIODS OF RAIN...OCCASIONALLY HEAVY...FROM THIS AFTERNOON
THROUGH TOMORROW.
* WINDS SHIFTING TO NELY TOMORROW AFTERNOON FOLLOWING THE PASSAGE
OF THE LOW PRESSURE CENTER.
KREIN
//DISCUSSION...UPDATED 18Z...
COPIOUS AMOUNTS OF MOISTURE CONTINUES TO STREAM NORTH ACROSS THE
REGION AS A DEEP LOW PRESSURE SYSTEM MOVES INTO CENTRAL MISSOURI,
A WEAK WARM FRONT EXTENDS ACROSS CNTRL IL/IN FROM THE LOW...WITH
MVFR/IFR CIGS AND ISOLD SHRA NORTH OF THE BOUNDARY...WITH HIGHER
MVFR CIGS TO THE SOUTH. CIGS HAVE BEEN BOUNCING ALL OVER THE PLACE
WITH RESPECT TO BASES TODAY...AND THIS TREND WILL LIKELY CONTINUE
THROUGH MUCH OF THE REMAINDER OF THE PERIOD. SO...IN
GENERAL...HAVE LOW CONFIDENCE IN THE TIMING AND DURATION OF WHEN
BASES WILL BE VFR...MVFR OR IFR. OCNL REDUCED VISIBILITY TO 4-5SM
IN SHRA WILL ALSO BE POSSIBLE THIS AFTERNOON.
AS THE SFC LOW SLOWLY TRACKS NEWD THE WARM FRONT WILL PUSH NORTH
OF THE TERMINALS...VEERING WINDS GRADUALLY TROUGH SELY TO SLY
OVERNIGHT WHILE ALSO STRENGTHENING. GUSTS UP TO 20KT ARE LIKELY
WAS WINDS TURN SELY...AND 25KT OR HIGHER LATER TONIGHT WITH
INCREASING PRESSURE FALLS AND A STRENGTHENING PRESSURE GRADIENT
WITH THE APPROACH OF THE LOW. THERE IS EVEN A CHANCE FOR SOME
STRONGER GUSTS TONIGHT...ESPECIALLY AROUND ANY THUNDERSTORMS AS A
LOW LEVEL JET OF 50-60KT MOVES OVERHEAD AND SOME OF THIS STRONGER
WIND COULD HAVE AN OPPORTUNITY TO MIX DOWN TO THE SFC. ALSO AS THE
SFC LOW APPROACHES...WIDESPREAD SHOWERS AND THUNDERSTORMS WILL
SPREAD ACROSS THE REGION...BUT THE GREATEST CHANGE FOR ORGANIZED
THUNDERSTORMS SHOULD GENERALLY BE SOUTH OF A LINE FROM VPZ TO PNT.
SOME ISOLATED...EMBEDDED THUNDER IS POSSIBLE NORTH OF THIS
LINE...BUT WILL KEEP ANY MENTION OF THUNDER OUT OF THE
TAFS...EXCEPT FOR GYY...AS ANY TS WILL LIKELY HAVE A VERY SPARSE
COVERAGE.
FOLLOWING THE PASSAGE OF THE ASSOCIATED COLD FRONT LATE TONIGHT
AND AS THE UPPER LOW MOVES OVER CNTRL IL TOMORROW...A SLOT OF DRY
AIR WILL OVERSPREAD THE REGION...SHUTTING OFF THE HEAVIER RAIN
POTENTIAL AND SETTING UP A PERIOD OF DRIZZLE AND LOW STRATUS INTO
THE LATE MORNING HOURS TOMORROW. A WIND SHIFT TO NELY WILL TAKE
PLACE TOMORROW AS THE SFC LOW SLOWLY TRACKS ACROSS THE REGION.
CURRENTLY ANTICIPATE THAT THE WIND SHIFT WILL OCCUR AT RFD BY ARND
12-13Z TOMORROW MORNING...BUT NOT UNTIL THE LATE AFTERNOON FOR THE
CHICAGO AREA TERMINALS. THIS WILL NOT BE THE END OF THE PCPN
POTENTIAL AS MOISTURE WRAPPING AROUND THE SYSTEM WILL BRING MORE
WIDESPREAD STRATIFORM RAIN AND IFR-MVFR CIGS AT LEAST INTO
TOMORROW EVENING.
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* LOW CONFIDENCE IN CIG TRENDS AND WITH BASES BOUNCING AROUND BTWN
MVFR AND IFR THROUGH THE AFTERNOON AND POSSIBLY INTO THE EVENING.
* MEDIUM CONFIDENCE IN VIS/PCPN TRENDS AND TIMING.
* MEDIUM TO HIGH CONFIDENCE THAT TS WILL REMAIN SOUTH AND EAST OF
THE TERMINALS.
* MEDIUM TO HIGH CONFIDENCE IN WIND DIR/SPEED TRENDS...WITH MEDIUM
CONFIDENCE IN EXACT TIMING.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT...OCNL -SHRA. MVFR CIGS LIKELY. STRONG NORTH TO
NORTHEAST WINDS POSSIBLE.
WEDNESDAY...OCNL -SHRA. MVFR CIGS PROBABLE...SMALL CHANCE OF IFR
CIGS.
THURSDAY...SMALL CHANCE OF -SHRA...PREDOMINANTLY VFR.
FRIDAY THROUGH SUNDAY...PREDOMINANTLY VFR.
BEACHLER
&&
.MARINE...
315 PM CDT
STRONG LOW PRESSURE LIFTING OUT OF MISSOURI LATE THIS AFTERNOON
HAS A WARM SECTOR THAT IS QUICKLY MOVING NORTHWARD ACROSS ILLINOIS
AND INDIANA. THIS WILL REACH THE FAR SOUTHERN PART OF THE LAKE BY
SUNSET...LEADING TO SMALL CRAFT CRITERIA WINDS. THE WINDS MAY BE
THE STRONGEST THIS EVENING ON THE INDIANA SHORE GIVEN THE OFFSHORE
COMPONENT...WHILE THE WAVES BUILDING THE QUICKEST ON THE ILLINOIS
SHORE WITH THE ONSHORE FLOW. DENSE FOG WILL LIKELY EASE QUICKLY
OVER THE FAR SOUTHERN PART OF THE LAKE INTO EARLY THIS
EVENING WITH THIS INCREASING FLOW...AS WELL AS RAIN MOVING
OVER THE LAKE HELPING TO MIX THE MARINE LAYER.
AS THE LOW PRESSURE APPROACHES THE LAKE IT WILL SLOW AS WELL AS
GRADUALLY EXPAND. THIS MAKES IT CHALLENGING FOR WINDS AS THE WARM
FRONTAL PORTION OF THIS LOW /SEPARATING NORTHEAST WINDS FROM
SOUTHEAST/ WILL EXTEND OVER THE LAKE AND WILL GRADUALLY WEAKEN
TOO. THIS DEMARKATION IN WINDS WILL LIKELY BE ACROSS THE CENTRAL
PART OF THE LAKE DURING THE DAY TUESDAY AND THEN GRADUALLY FADE
INTO THE DAY WEDNESDAY...ALLOWING NORTHERLY WINDS TO ENVELOP
SOUTHWARD. THIS COULD HAPPEN MORE QUICKLY THOUGH WHICH WOULD LEAD
TO SMALL CRAFT CRITERIA WAVES AND POSSIBLY WINDS INTO THE ILLINOIS
NEARSHORE LATE TUESDAY INTO TUESDAY EVENING.
IN ADDITION...IT IS POSSIBLE TEMPORARY NORTHEAST GALES COULD BE
EXPERIENCED ON THE NORTHERN PART OF THE LAKE TUESDAY NORTH OF THE
WARM FRONT.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 5 AM TUESDAY.
DENSE FOG ADVISORY...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-
LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-
LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 PM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
122 PM CDT MON OCT 13 2014
.DISCUSSION...
1130 AM CDT
HAVE MADE SOME FINE TUNING ON START TIME TO RAIN THIS
AFTERNOON...ALL MOSTLY MINOR. NO SIGNIFICANT SHIFTS IN THINKING
FOR FORECAST OF THE NORTHERN EXTENT OF POTENTIALLY MORE ROBUST
STORMS OR RAINFALL AMOUNTS AND PLACEMENT TONIGHT.
THE WELL-DEFINED CLASSIC TRANSITION SEASON SYSTEM IS MOVING INTO
EASTERN OK WITH A MOIST CONVEYOR BELT RAPIDLY RACING EXTENDING
NORTHWARD AHEAD OF THIS WITHIN RAPIDLY INCREASING UPPER SUPPORT
FOR LIFT. THE SYSTEM LOW-LEVEL JET SAMPLED ON THE LSX VAD
PROFILER HAS STRENGTHENED SHARPLY THROUGH THE MORNING WITH 60 KT
OF FLOW AT 5000 FT. REGIONAL RADAR IS ALREADY SHOWING THE TREND OF
INCREASING ARCS OF SHOWERS ACROSS CENTRAL IL AND UP TO INTERSTATE
80. THIS WILL CONTINUE WITHIN THE MOIST ADVECTION PATTERN...WITH
WIDESPREAD RAIN AND PROBABLY SOME EMBEDDED THUNDER SUCH AS SEEN
IN WESTERN IL/SOUTHEAST IA/NORTHEAST MO BLOSSOMING INTO NORTH
CENTRAL IL EARLY THIS AFTERNOON ALONG THE DEEPER MOISTURE
CONVERGENCE. TEMPERATURES LIKELY WILL FLATLINE IN THESE PLACES
WHILE FURTHER EAST WHERE SOME BREAKS IN AFTERNOON SHOWER ACTIVITY
WILL OCCUR...ADVECTION WILL STILL LIKELY SUPPORT A SLOW
TEMPERATURE CLIMB. ALONG THE NORTHEAST IL LAKE MI SHORE...INCLUDING
CHICAGO...THERE MAY BE SOME FINGERS OF DENSE FOG WITH THE ONSHORE
FLOW AND PERSISTENT FOG PER SATELLITE AND WEBCAM IMAGES.
THE 998MB LOW IN SOUTHWEST MO AT 11 AM IS FORECAST BY A MEAN OF
HIGH RES MODELS TO BE NEAR THE QUAD CITIES BY 10 PM AND HAVING
DEEPENED A COUPLE MORE MB. SUCH A PATH SUPPORTS THE WARM SECTOR
TO PUSH INTO THE SOUTHEAST FORECAST AREA THIS AFTERNOON AND
POSSIBLY NORTH OF I-80 THIS EVENING. THIS WILL BE DILUTED SOMEWHAT
WITH ALL THE SHOWER AN STORM ACTIVITY EXPECTED TO DEVELOP THIS
AFTERNOON...AND ALSO WITH THE WIDESPREAD ACTIVITY OVER THE MID AND
LOWER MISSISSIPPI VALLEY /UPSTREAM IN LOW-LEVEL FLOW
TRAJECTORIES/. NONETHELESS...THERE IS A FAVORED WINDOW THIS
EVENING FOR STORMS AHEAD OF THE LOW TO MOVE ACROSS THE SOUTHEAST
FORECAST AREA THAT COULD REALIZE SOME OF THE LOWEST
INSTABILITY...WHICH IS JUST OFF THE DECK ON HIGH-RES MODEL
SOUNDINGS. CONDITIONALLY IF A SEGMENT OF STORMS DOES DEVELOP AND
MOVE OVER THAT AREA THIS EVE...SHEAR PROFILES REMAIN SUPPORTIVE OF
ORGANIZATION CAPABLE OF ISOLATED SEVERE WINDS AND A NON-ZERO BRIEF
TORNADO THREAT WITH BACKED INFLOW VECTORS. EFFICIENT RAINFALL WILL
CERTAINLY BE MORE REALIZED OVER A LARGER AREA...WITH SOME
LOCALIZED FLOODING NOT OUT OF THE QUESTION WITH HIGHLY ANOMALOUS
VALUES OF MOISTURE AND ITS REPLENISHMENT LATE TODAY AND THIS
EVENING.
MTF
//PREV DISCUSSION...
345 AM CDT
TODAY THROUGH WEDNESDAY NIGHT...
FORECAST ISSUES THIS MORNING CONTINUE TO CENTER AROUND THE
SIGNIFICANT STORM SYSTEM EXPECTED TO IMPACT THE REGION FOR THE NEXT
COUPLE OF DAYS. MAIN FORECAST CONCERNS WILL BE THE POTENTIAL FOR ANY
SEVERE WEATHER...ESPECIALLY LATER TODAY INTO THIS EVENING...AND ALSO
WITH REGARDS TO WHERE THE HEAVIEST RAINFALL AMOUNTS WILL FALL...AND
IF ANY HYDRO CONDITIONS MAY ARISE.
WATER VAPOR IMAGERY EARLY THIS MORNING SHOWS THE VIGOROUS MAIN
MID/UPPER LEVEL IMPULSE NOW BEGINNING TO MOVE THROUGH THE BASE OF THE
TROUGH ACROSS THE TEXAS PANHANDLE. A RAPID UPTAKE IN THE DYNAMIC
FORCING FOR ASCENT DOWNSTREAM OF THIS FEATURE CAN BE JUGGED JUST BY
THE SHEAR AMOUNT OF SHOWERS AND STORMS THAT SPAWNED ACROSS THE
SOUTHERN PLAINS YESTERDAY EVENING.
SHOWERS SHOULD REMAIN WIDELY SCATTERED ACROSS THE AREA FOR MUCH OF
THE MORNING. HOWEVER...SHOWER AND THUNDERSTORM ACTIVITY SHOULD
INCREASE ACROSS THE AREA FROM NORTH TO SOUTH THROUGH THE AFTERNOON
AS A STRONG SURGE OF MOISTURE OCCURS ALONG TO THE NOSE OF A
DEVELOPING/STRENGTHENING LOW LEVEL JET. THIS LOW LEVEL JET IS PROGGED
TO INCREASE TO 50 TO 60 KT BY EARLY THIS EVENING AS THE LOWER LEVEL
CIRCULATION STRENGTHENS OVER THE MID MISSOURI VALLEY. THIS ALL LOOKS
TO HAPPEN IN RESPONSE TO THE RAPIDLY CLOSING OFF MID LEVEL
CIRCULATION...AND ASSOCIATED INCREASE IN UPPER LEVEL DIVERGENCE
WITHIN THE VICINITY OF THE EXIT REGION OF A STRENGTHENING UPPER JET
IMPULSE OVER THE OZARKS.
THIS INCREASING WIND FIELD WILL PUMP IN UNSEASONABLY HIGH AMOUNTS OF
DEEP ATMOSPHERIC MOISTURE...WITH MODEL PROGS STILL INDICATING
UPWARDS OF 1.6" PRECIPITABLE WATER VALUES...WHICH WOULD RANK WITHIN
THE 99 PERCENTILE FOR OCTOBER. THUS THIS WILL UNDOUBTEDLY SUPPORT
SOME HEFTY RAINFALL AMOUNTS ACROSS PORTIONS OF THE REGION INTO
TUESDAY MORNING. THE BIG QUESTION...HOWEVER...AT THIS TIME CONTINUES
TO BE WHICH AREAS WILL BE FAVORED FOR THE HEAVIEST RAINFALL AMOUNTS.
CURRENT MODEL GUIDANCE IS IN GOOD AGREEMENT SUGGESTING THAT ONE OF
THESE AREAS COULD BE PORTIONS OF NORTH CENTRAL ILLINOIS AND INTO
WISCONSIN...WHERE A DEFORMATION AXIS SHOULD SET UP THIS AFTERNOON
AND EVENING. AS SUCH...STRONG MOISTURE CONVERGENCE AND FGEN SHOULD
SET UP HERE ALONG THE NOSE OF THE LOWER LEVEL JET LATE THIS
AFTERNOON AND EVENING...SUPPORTING A GOOD SOAKING MODERATE RAINFALL.
A GOOD 1 TO 2 INCHES COULD FALL IN THIS AREA BY TUESDAY MORNING.
ANOTHER AREA OF THUNDERSTORMS...LIKELY CONTAINING VERY HEAVY
RAINFALL...SHOULD DEVELOP OVER MISSOURI LATER TODAY...THEN SHIFT
EASTWARD ACROSS ILLINOIS THIS EVENING AND OVERNIGHT. THIS ACTIVITY
COULD RESULT IN PERIODS OF VERY HEAVY RAINFALL ACROSS SOUTHERN AND
EASTERN SECTIONS OF MY AREA TONIGHT INTO EARLY TUESDAY. AT THIS TIME
I DO NOT HAVE ENOUGH CONFIDENCE TO ISSUE ANY TYPE OF FLOOD
WATCH...AS GUIDANCE IS UNCERTAIN IN HOW FAR EASTWARD THE MID LEVEL
DRY SLOT WILL REACH TONIGHT...WHICH WILL HAVE LARGE IMPLICATIONS ON
THE AMOUNT OF RAINFALL THAT FALLS ACROSS THIS AREA. THIS AREA WILL
NEED TO BE WATCHED FOR THE POSSIBILITY OF SOME HYDRO
ISSUES...ESPECIALLY IF ANY INDIVIDUAL STORMS TENDS TO TRAIN
NORTHWARD ACROSS THE SAME AREAS.
IN ADDITION TO THE HEAVY RAIN THREAT...SOME SEVERE STORMS ARE STILL
POSSIBLE ACROSS MY SOUTHERN COUNTIES ACROSS CENTRAL ILLINOIS AND
NORTHWESTERN INDIANA AND POINTS SOUTH. ALTHOUGH INSTABILITY WILL BE
WEAK...WITH PLENTY OF LOW CLOUDS THROUGH THE DAY...THE LARGE AMOUNTS
OF LOW AND DEEP LAYER SHEAR COULD SUPPORT A LOW END THREAT FOR
STRONG DAMAGING WINDS AND OR A TORNADO OR TWO...ESPECIALLY WITH ANY
ORGANIZED ACTIVE THAT MOVES OVER THESE AREAS LATE THIS AFTERNOON
AND EVENING. THE HIGH DEWPOINT AIR WILL LIKELY LEAD TO LITTLE IF ANY
BOUNDARY LAYER COOLING THIS EVENING...SO THIS THREAT COULD EXTEND
INTO THE EVENING. HOWEVER...THE BETTER CHANCES OF SEVERE STORMS
LOOKS TO REMAIN FARTHER SOUTH OF THE AREA.
THE UPPER LOW STILL LOOKS TO REMAIN IN PLACE ACROSS THE AREA OVER
THE NEXT FEW DAYS. THIS WILL RESULT IN SOME PERIODS OF SHOWERS
ACROSS THE AREA THROUGH THURSDAY.
KJB
THURSDAY THROUGH SUNDAY...
500MB TROUGH OVER THE GREAT LAKES WILL BEGIN TO FLATTEN...HOWEVER
SOME WEAK RIDGING ACROSS THE NORTH ATLANTIC WILL LIKELY SLOW THE
DEPARTURE OF THE TROUGH. GUIDANCE THEN SUGGESTS ANOTHER SHORTWAVE
WILL SLIDE SOUTHEAST FROM THE CANADIAN ROCKIES FRI AND ARRIVE OVER
CENTRAL ONTARIO/NORTHERN GREAT LAKES LATE FRIDAY/EARLY SAT. THEN
HEIGHTS ARE PROGGED TO INCREASE ACROSS THE WESTERN CONUS...WITH THE
POTENTIAL FOR A STRONGER WAVE/TROUGH DIGGING INTO THE EASTERN
PACIFIC. THIS COULD RESULT IN SHIFTING THE BUILDING WESTERN CONUS
RIDGE FURTHER EAST LATE IN THE WEEKEND INTO EARLY THE FOLLOWING
WEEK. OUTSIDE OF SOME OCCASIONAL CHANCES FOR SHOWERS IN THE CURRENT
EXTENDED PERIODS...THERE DOES NOT APPEAR TO BE ANY NOTABLE SYSTEMS
POISED TO IMPACT THE REGION. TEMPERATURES WILL ALSO GENERALLY BE IN
THE 60S...HOWEVER WITH INCREASED CLOUDS AND THE WEEKEND SHORTWAVE
SYSTEM...TEMPS COULD STRUGGLE TO WARM BEYOND THE 50S SAT/SUN.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* OCNL PERIODS MVFR/IFR CIGS AND MVFR VIS AS A STRONG STORM SYSTEM
MOVES THROUGH THE REGION.
* LIGHT WINDS SELY-ELY THROUGH ARND NOON...THEN BECMG SELY AND
INCRG TO 10-12KT.
* WINDS BECMG SELY AND INCREASING TO 12G18-20KT THROUGH THE
AFTERNOON...BECMG SLY AND INCRG TO 18G25KT OR POSSIBLY HIGHER
LATE EVENING TO LATE NIGHT TONIGHT.
* PERIODS OF RAIN...OCCASIONALLY HEAVY...FROM THIS AFTERNOON
THROUGH TOMORROW.
* WINDS SHIFTING TO NELY TOMORROW AFTERNOON FOLLOWING THE PASSAGE
OF THE LOW PRESSURE CENTER.
KREIN
//DISCUSSION...UPDATED 18Z...
COPIOUS AMOUNTS OF MOISTURE CONTINUES TO STREAM NORTH ACROSS THE
REGION AS A DEEP LOW PRESSURE SYSTEM MOVES INTO CENTRAL MISSOURI,
A WEAK WARM FRONT EXTENDS ACROSS CNTRL IL/IN FROM THE LOW...WITH
MVFR/IFR CIGS AND ISOLD SHRA NORTH OF THE BOUNDARY...WITH HIGHER
MVFR CIGS TO THE SOUTH. CIGS HAVE BEEN BOUNCING ALL OVER THE PLACE
WITH RESPECT TO BASES TODAY...AND THIS TREND WILL LIKELY CONTINUE
THROUGH MUCH OF THE REMAINDER OF THE PERIOD. SO...IN
GENERAL...HAVE LOW CONFIDENCE IN THE TIMING AND DURATION OF WHEN
BASES WILL BE VFR...MVFR OR IFR. OCNL REDUCED VISIBILITY TO 4-5SM
IN SHRA WILL ALSO BE POSSIBLE THIS AFTERNOON.
AS THE SFC LOW SLOWLY TRACKS NEWD THE WARM FRONT WILL PUSH NORTH
OF THE TERMINALS...VEERING WINDS GRADUALLY TROUGH SELY TO SLY
OVERNIGHT WHILE ALSO STRENGTHENING. GUSTS UP TO 20KT ARE LIKELY
WAS WINDS TURN SELY...AND 25KT OR HIGHER LATER TONIGHT WITH
INCREASING PRESSURE FALLS AND A STRENGTHENING PRESSURE GRADIENT
WITH THE APPROACH OF THE LOW. THERE IS EVEN A CHANCE FOR SOME
STRONGER GUSTS TONIGHT...ESPECIALLY AROUND ANY THUNDERSTORMS AS A
LOW LEVEL JET OF 50-60KT MOVES OVERHEAD AND SOME OF THIS STRONGER
WIND COULD HAVE AN OPPORTUNITY TO MIX DOWN TO THE SFC. ALSO AS THE
SFC LOW APPROACHES...WIDESPREAD SHOWERS AND THUNDERSTORMS WILL
SPREAD ACROSS THE REGION...BUT THE GREATEST CHANGE FOR ORGANIZED
THUNDERSTORMS SHOULD GENERALLY BE SOUTH OF A LINE FROM VPZ TO PNT.
SOME ISOLATED...EMBEDDED THUNDER IS POSSIBLE NORTH OF THIS
LINE...BUT WILL KEEP ANY MENTION OF THUNDER OUT OF THE
TAFS...EXCEPT FOR GYY...AS ANY TS WILL LIKELY HAVE A VERY SPARSE
COVERAGE.
FOLLOWING THE PASSAGE OF THE ASSOCIATED COLD FRONT LATE TONIGHT
AND AS THE UPPER LOW MOVES OVER CNTRL IL TOMORROW...A SLOT OF DRY
AIR WILL OVERSPREAD THE REGION...SHUTTING OFF THE HEAVIER RAIN
POTENTIAL AND SETTING UP A PERIOD OF DRIZZLE AND LOW STRATUS INTO
THE LATE MORNING HOURS TOMORROW. A WIND SHIFT TO NELY WILL TAKE
PLACE TOMORROW AS THE SFC LOW SLOWLY TRACKS ACROSS THE REGION.
CURRENTLY ANTICIPATE THAT THE WIND SHIFT WILL OCCUR AT RFD BY ARND
12-13Z TOMORROW MORNING...BUT NOT UNTIL THE LATE AFTERNOON FOR THE
CHICAGO AREA TERMINALS. THIS WILL NOT BE THE END OF THE PCPN
POTENTIAL AS MOISTURE WRAPPING AROUND THE SYSTEM WILL BRING MORE
WIDESPREAD STRATIFORM RAIN AND IFR-MVFR CIGS AT LEAST INTO
TOMORROW EVENING.
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* LOW CONFIDENCE IN CIG TRENDS AND WITH BASES BOUNCING AROUND BTWN
MVFR AND IFR THROUGH THE AFTERNOON AND POSSIBLY INTO THE EVENING.
* MEDIUM CONFIDENCE IN VIS/PCPN TRENDS AND TIMING.
* MEDIUM TO HIGH CONFIDENCE THAT TS WILL REMAIN SOUTH AND EAST OF
THE TERMINALS.
* MEDIUM TO HIGH CONFIDENCE IN WIND DIR/SPEED TRENDS...WITH MEDIUM
CONFIDENCE IN EXACT TIMING.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT...OCNL -SHRA. MVFR CIGS LIKELY. STRONG NORTH TO
NORTHEAST WINDS POSSIBLE.
WEDNESDAY...OCNL -SHRA. MVFR CIGS PROBABLE...SMALL CHANCE OF IFR
CIGS.
THURSDAY...SMALL CHANCE OF -SHRA...PREDOMINANTLY VFR.
FRIDAY THROUGH SUNDAY...PREDOMINANTLY VFR.
BEACHLER
&&
.MARINE...
219 AM CDT
MAIN CONCERN RESIDES WITH THE WINDS IN THE NEARSHORE FOR
TONIGHT...WHICH APPEARS TO BE BODERLINE SMALL CRAFT CRITERIA. THEN
THE GRADIENT QUICKLY DIMINISHES ARND DAYBREAK TUE...HOWEVER THIS
LOOKS TO ONLY BE TEMPORARY. TUE NGT ONCE THE LOW DRIFTS EAST OF
THE LAKE...THE GRADIENT IS POISED TO QUICKLY RAMP BACK UP.
GUIDANCE CONTINUES TO SUGGEST A PERIOD OF GALES WILL DEVELOP LATE
TUE EVENING THROUGH WED.
LOW PRESSURE EARLY THIS MORNING REMAINS WELL SOUTH OF LAKE
MICHIGAN NEAR CENTRAL OKLAHOMA...HOWEVER THIS LOW IS EXPECTED TO
STEADILY DEEPEN AS IT LIFTS NORTHEAST INTO CENTRAL MISSOURI BY
MID-MORNING. WINDS ACROSS THE SOUTHERN PORTION OF THE LAKE WILL
BEGIN TO INCREASE FROM THE SOUTHEAST...WHICH SHOULD BE ABLE TO
BUILD THE WAVES ALONG THE ILLINOIS NEARSHORE. THE WILDCARD IS THAT
WITH WARMER AIR FLOWING OVER THE LAKE THIS MAY RESULT IN WINDS NOT
EFFECTIVELY REACHING THE SFC. EARLIER GUIDANCE WAS INDICATING THAT
WINDS COULD BE STRONGER...BUT HAVE BEGUN TO BACK OFF FROM THIS FOR
THE SOUTHERN PORTION OF THE LAKE. THEN AS THE LOW DRIFTS EAST OF
THE LAKE...THE GRADIENT QUICKLY INCREASES FROM THE NORTH TO SOUTH
TUESDAY EVENING INTO WEDNESDAY. THIS APPEARS TO BE A FAVORABLE
PERIOD WHEN GALES TO 35KT MAY OCCUR. THE HIGHEST CONFIDENCE IS ON
THE WINDS BEING 30KT. HAVE HELD OFF ON A GALE WATCH AT THIS
TIME...BUT COULD SEE ONE BEING NEEDED FOR TUE NGT/WED. WAVES WILL
EASILY BUILD. THE NORTHERN/CENTRAL PORTIONS OF THE LAKE HAVE THE
BEST CHANCE TO SEE GALE FORCE GUSTS. EXPECT WAVES TO INCREASE
CONSIDERABLY...ESPECIALLY TUESDAY INTO WEDNESDAY AS A NORTHERLY
FETCH OF WINDS CONTINUES FOR AN EXTENDED PERIOD OF TIME. THE LOW
EVENTUALLY FILLS AND GETS KICKED EAST BY ANOTHER SYSTEM MOVING
THROUGH SOUTHERN CANADA.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...NEARSHORE WATERS
UNTIL 4 PM MONDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...10 PM MONDAY TO 5 AM TUESDAY.
DENSE FOG ADVISORY...LMZ080-LMZ366-LMZ565-LMZ567-LMZ669-LMZ671-
LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-
LMZ876-LMZ878 UNTIL 9 PM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1231 PM CDT Mon Oct 13 2014
.UPDATE...
ISSUED AT 1023 AM CDT MON OCT 13 2014
Leading warm front/boundary is steadily lifting northward across
the forecast area, extending roughly along a Quincy to Rantoul
line at 10 am. Visibilities have been steadily improving as the
front moves north, with only isolated areas below 2 miles left.
The big question remains with the potential for severe weather.
Line of storms currently in southeast Missouri extends all the way
into eastern Texas. 0-6km bulk shear already in the 50-60 knot
range along the Illinois/Missouri border and the RAP model shifts
this into central Illinois over the next few hours. Very little
sunshine if any to fuel the fire, with MUCAPE`s only rising into
the 500-1000 J/kg range, but the overall dynamics may be enough to
overcome this limitation. High-res models all agree in a narrow,
fast moving squall line, but have a spread of 2-6 hours in terms
of when the line actually moves through. Latest HRRR brings it as
early as 3 pm around Springfield, ranging to 6 pm with the NSSL
ARW and 8 pm with the 1km NAM nest. The northward movement of the
cells in Missouri would lead some credence to the earlier
solutions.
Have made some timing adjustments to the PoP`s in the grids
through tonight, and also added some mention of severe storms
across the south half of the area late afternoon/early evening.
Temperature trends currently on track.
&&
.SHORT TERM...(Today)
ISSUED AT 342 AM CDT MON OCT 13 2014
High pressure ridge over both east and west coast with a deepening
and slow-moving trof dominating the Plains, moving into the
Midwest. Deepening surface low providing today`s storm system for
the region. Models pretty consistent in depicting this storm in
two main sections...with the frontal convection to the south and the
deformation zone wrapping around the NW side of the low just to
the north. Some issues with the forecast surrounding the placement
of pops to cover the trends with some uncertainty around the
timing and the depth of the dry slot. NAM and GFS all becoming
more pronounced with the dry air in the last run...and the ECMWF
coming into line as well. NSSL WRF even more aggressive with the
dry wedge...also far more showery with regards to the activity
into tonight. Under a slight risk for severe storms today, the
better shear profile to the south with the moderate risk in the
southern tip of the state and western KY...combined with a better
chance for temperature recovery from any showers over the area
this morning. This far north will be tough to scour out the
clouds, though any clearing should be watched closely for
re-energizing ahead of the system... priming for severe weather
activity.
&&
.LONG TERM...(Tonight through Sunday)
ISSUED AT 342 AM CDT MON OCT 13 2014
Models have been very consistent in the last few runs with dropping
the wave into the region and cutting off the 500mb low, parking it
over the region through midweek. Tonight, the storm remains overhead
before wrapping up on itself. Threat for the stronger convection
shifts to the east before midnight... then the pops starting to
lessen with the impact of the dry slot building north into the
state. Exact location of the dry slot adding in some
uncertainty...though the precip after midnight, particularly to the
north and northwest may be dominated with mostly drizzle, but fairly
consistent enough to keep wet and plenty of low clouds through the
early morning hours.
Next couple of days will improve only slightly as the upper low
grows mostly stagnant over the region. Deformation zone starts to
lose structure as the low wraps up on Tuesday and convection from
the front races out ahead of the actual low. Cloudy, gray, showery
and cool conditions continue through Wednesday night under the
persistent cyclonic flow....likely to be dominated by rain without
thunder. Drying out on Thursday as the low finally gets kicked to
the east by another wave diving into the Great Lakes region. ECMWF
pushing a quick short wave into the region late Sun and into
Mon...GFS is dry, so the blend is starting to put some pops into the
forecast. Tempering them for now to low chance with the nature of a
fast short wave in NWrly flow on day 7/8...not a big concern at this
point.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
ISSUED AT 1230 PM CDT MON OCT 13 2014
Challenging TAF forecast for the next 24 hours. As of midday,
ceilings over most of the TAF sites have crept up to around
1200-1500 feet, but lower IFR/LIFR linger near KPIA. While a
widespread area of showers exists from KPIA-KSPI westward and more
isolated showers extend east, starting to see an increase in
lightning activity on the leading edge of the rain shield. High-
resolution model guidance sweep a fast moving line of storms east
across the state through about 02Z, although largely missing
KPIA/KBMI. The showers should taper off for a time during the
evening as a dry slot punches northeast into central Illinois, but
will likely see some drizzle/light fog until late night, at which
point wraparound shower will begin spreading back in from west to
east. Think that IFR/LIFR conditions are the way to go through the
night, with some improvement mid/late Tuesday morning.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Geelhart
SHORT TERM...HJS
LONG TERM...HJS
AVIATION...Geelhart
AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
1130 AM CDT MON OCT 13 2014
.DISCUSSION...
1130 AM CDT
HAVE MADE SOME FINE TUNING ON START TIME TO RAIN THIS
AFTERNOON...ALL MOSTLY MINOR. NO SIGNIFICANT SHIFTS IN THINKING
FOR FORECAST OF THE NORTHERN EXTENT OF POTENTIALLY MORE ROBUST
STORMS OR RAINFALL AMOUNTS AND PLACEMENT TONIGHT.
THE WELL-DEFINED CLASSIC TRANSITION SEASON SYSTEM IS MOVING INTO
EASTERN OK WITH A MOIST CONVEYOR BELT RAPIDLY RACING EXTENDING
NORTHWARD AHEAD OF THIS WITHIN RAPIDLY INCREASING UPPER SUPPORT
FOR LIFT. THE SYSTEM LOW-LEVEL JET SAMPLED ON THE LSX VAD
PROFILER HAS STRENGTHENED SHARPLY THROUGH THE MORNING WITH 60 KT
OF FLOW AT 5000 FT. REGIONAL RADAR IS ALREADY SHOWING THE TREND OF
INCREASING ARCS OF SHOWERS ACROSS CENTRAL IL AND UP TO INTERSTATE
80. THIS WILL CONTINUE WITHIN THE MOIST ADVECTION PATTERN...WITH
WIDESPREAD RAIN AND PROBABLY SOME EMBEDDED THUNDER SUCH AS SEEN
IN WESTERN IL/SOUTHEAST IA/NORTHEAST MO BLOSSOMING INTO NORTH
CENTRAL IL EARLY THIS AFTERNOON ALONG THE DEEPER MOISTURE
CONVERGENCE. TEMPERATURES LIKELY WILL FLATLINE IN THESE PLACES
WHILE FURTHER EAST WHERE SOME BREAKS IN AFTERNOON SHOWER ACTIVITY
WILL OCCUR...ADVECTION WILL STILL LIKELY SUPPORT A SLOW
TEMPERATURE CLIMB. ALONG THE NORTHEAST IL LAKE MI SHORE...INCLUDING
CHICAGO...THERE MAY BE SOME FINGERS OF DENSE FOG WITH THE ONSHORE
FLOW AND PERSISTENT FOG PER SATELLITE AND WEBCAM IMAGES.
THE 998MB LOW IN SOUTHWEST MO AT 11 AM IS FORECAST BY A MEAN OF
HIGH RES MODELS TO BE NEAR THE QUAD CITIES BY 10 PM AND HAVING
DEEPENED A COUPLE MORE MB. SUCH A PATH SUPPORTS THE WARM SECTOR
TO PUSH INTO THE SOUTHEAST FORECAST AREA THIS AFTERNOON AND
POSSIBLY NORTH OF I-80 THIS EVENING. THIS WILL BE DILUTED SOMEWHAT
WITH ALL THE SHOWER AN STORM ACTIVITY EXPECTED TO DEVELOP THIS
AFTERNOON...AND ALSO WITH THE WIDESPREAD ACTIVITY OVER THE MID AND
LOWER MISSISSIPPI VALLEY /UPSTREAM IN LOW-LEVEL FLOW
TRAJECTORIES/. NONETHELESS...THERE IS A FAVORED WINDOW THIS
EVENING FOR STORMS AHEAD OF THE LOW TO MOVE ACROSS THE SOUTHEAST
FORECAST AREA THAT COULD REALIZE SOME OF THE LOWEST
INSTABILITY...WHICH IS JUST OFF THE DECK ON HIGH-RES MODEL
SOUNDINGS. CONDITIONALLY IF A SEGMENT OF STORMS DOES DEVELOP AND
MOVE OVER THAT AREA THIS EVE...SHEAR PROFILES REMAIN SUPPORTIVE OF
ORGANIZATION CAPABLE OF ISOLATED SEVERE WINDS AND A NON-ZERO BRIEF
TORNADO THREAT WITH BACKED INFLOW VECTORS. EFFICIENT RAINFALL WILL
CERTAINLY BE MORE REALIZED OVER A LARGER AREA...WITH SOME
LOCALIZED FLOODING NOT OUT OF THE QUESTION WITH HIGHLY ANOMALOUS
VALUES OF MOISTURE AND ITS REPLENISHMENT LATE TODAY AND THIS
EVENING.
MTF
&&
.PREV DISCUSSION...
345 AM CDT
TODAY THROUGH WEDNESDAY NIGHT...
FORECAST ISSUES THIS MORNING CONTINUE TO CENTER AROUND THE
SIGNIFICANT STORM SYSTEM EXPECTED TO IMPACT THE REGION FOR THE NEXT
COUPLE OF DAYS. MAIN FORECAST CONCERNS WILL BE THE POTENTIAL FOR ANY
SEVERE WEATHER...ESPECIALLY LATER TODAY INTO THIS EVENING...AND ALSO
WITH REGARDS TO WHERE THE HEAVIEST RAINFALL AMOUNTS WILL FALL...AND
IF ANY HYDRO CONDITIONS MAY ARISE.
WATER VAPOR IMAGERY EARLY THIS MORNING SHOWS THE VIGOROUS MAIN
MID/UPPER LEVEL IMPULSE NOW BEGINNING TO MOVE THROUGH THE BASE OF THE
TROUGH ACROSS THE TEXAS PANHANDLE. A RAPID UPTAKE IN THE DYNAMIC
FORCING FOR ASCENT DOWNSTREAM OF THIS FEATURE CAN BE JUGGED JUST BY
THE SHEAR AMOUNT OF SHOWERS AND STORMS THAT SPAWNED ACROSS THE
SOUTHERN PLAINS YESTERDAY EVENING.
SHOWERS SHOULD REMAIN WIDELY SCATTERED ACROSS THE AREA FOR MUCH OF
THE MORNING. HOWEVER...SHOWER AND THUNDERSTORM ACTIVITY SHOULD
INCREASE ACROSS THE AREA FROM NORTH TO SOUTH THROUGH THE AFTERNOON
AS A STRONG SURGE OF MOISTURE OCCURS ALONG TO THE NOSE OF A
DEVELOPING/STRENGTHENING LOW LEVEL JET. THIS LOW LEVEL JET IS PROGGED
TO INCREASE TO 50 TO 60 KT BY EARLY THIS EVENING AS THE LOWER LEVEL
CIRCULATION STRENGTHENS OVER THE MID MISSOURI VALLEY. THIS ALL LOOKS
TO HAPPEN IN RESPONSE TO THE RAPIDLY CLOSING OFF MID LEVEL
CIRCULATION...AND ASSOCIATED INCREASE IN UPPER LEVEL DIVERGENCE
WITHIN THE VICINITY OF THE EXIT REGION OF A STRENGTHENING UPPER JET
IMPULSE OVER THE OZARKS.
THIS INCREASING WIND FIELD WILL PUMP IN UNSEASONABLY HIGH AMOUNTS OF
DEEP ATMOSPHERIC MOISTURE...WITH MODEL PROGS STILL INDICATING
UPWARDS OF 1.6" PRECIPITABLE WATER VALUES...WHICH WOULD RANK WITHIN
THE 99 PERCENTILE FOR OCTOBER. THUS THIS WILL UNDOUBTEDLY SUPPORT
SOME HEFTY RAINFALL AMOUNTS ACROSS PORTIONS OF THE REGION INTO
TUESDAY MORNING. THE BIG QUESTION...HOWEVER...AT THIS TIME CONTINUES
TO BE WHICH AREAS WILL BE FAVORED FOR THE HEAVIEST RAINFALL AMOUNTS.
CURRENT MODEL GUIDANCE IS IN GOOD AGREEMENT SUGGESTING THAT ONE OF
THESE AREAS COULD BE PORTIONS OF NORTH CENTRAL ILLINOIS AND INTO
WISCONSIN...WHERE A DEFORMATION AXIS SHOULD SET UP THIS AFTERNOON
AND EVENING. AS SUCH...STRONG MOISTURE CONVERGENCE AND FGEN SHOULD
SET UP HERE ALONG THE NOSE OF THE LOWER LEVEL JET LATE THIS
AFTERNOON AND EVENING...SUPPORTING A GOOD SOAKING MODERATE RAINFALL.
A GOOD 1 TO 2 INCHES COULD FALL IN THIS AREA BY TUESDAY MORNING.
ANOTHER AREA OF THUNDERSTORMS...LIKELY CONTAINING VERY HEAVY
RAINFALL...SHOULD DEVELOP OVER MISSOURI LATER TODAY...THEN SHIFT
EASTWARD ACROSS ILLINOIS THIS EVENING AND OVERNIGHT. THIS ACTIVITY
COULD RESULT IN PERIODS OF VERY HEAVY RAINFALL ACROSS SOUTHERN AND
EASTERN SECTIONS OF MY AREA TONIGHT INTO EARLY TUESDAY. AT THIS TIME
I DO NOT HAVE ENOUGH CONFIDENCE TO ISSUE ANY TYPE OF FLOOD
WATCH...AS GUIDANCE IS UNCERTAIN IN HOW FAR EASTWARD THE MID LEVEL
DRY SLOT WILL REACH TONIGHT...WHICH WILL HAVE LARGE IMPLICATIONS ON
THE AMOUNT OF RAINFALL THAT FALLS ACROSS THIS AREA. THIS AREA WILL
NEED TO BE WATCHED FOR THE POSSIBILITY OF SOME HYDRO
ISSUES...ESPECIALLY IF ANY INDIVIDUAL STORMS TENDS TO TRAIN
NORTHWARD ACROSS THE SAME AREAS.
IN ADDITION TO THE HEAVY RAIN THREAT...SOME SEVERE STORMS ARE STILL
POSSIBLE ACROSS MY SOUTHERN COUNTIES ACROSS CENTRAL ILLINOIS AND
NORTHWESTERN INDIANA AND POINTS SOUTH. ALTHOUGH INSTABILITY WILL BE
WEAK...WITH PLENTY OF LOW CLOUDS THROUGH THE DAY...THE LARGE AMOUNTS
OF LOW AND DEEP LAYER SHEAR COULD SUPPORT A LOW END THREAT FOR
STRONG DAMAGING WINDS AND OR A TORNADO OR TWO...ESPECIALLY WITH ANY
ORGANIZED ACTIVE THAT MOVES OVER THESE AREAS LATE THIS AFTERNOON
AND EVENING. THE HIGH DEWPOINT AIR WILL LIKELY LEAD TO LITTLE IF ANY
BOUNDARY LAYER COOLING THIS EVENING...SO THIS THREAT COULD EXTEND
INTO THE EVENING. HOWEVER...THE BETTER CHANCES OF SEVERE STORMS
LOOKS TO REMAIN FARTHER SOUTH OF THE AREA.
THE UPPER LOW STILL LOOKS TO REMAIN IN PLACE ACROSS THE AREA OVER
THE NEXT FEW DAYS. THIS WILL RESULT IN SOME PERIODS OF SHOWERS
ACROSS THE AREA THROUGH THURSDAY.
KJB
THURSDAY THROUGH SUNDAY...
500MB TROUGH OVER THE GREAT LAKES WILL BEGIN TO FLATTEN...HOWEVER
SOME WEAK RIDGING ACROSS THE NORTH ATLANTIC WILL LIKELY SLOW THE
DEPARTURE OF THE TROUGH. GUIDANCE THEN SUGGESTS ANOTHER SHORTWAVE
WILL SLIDE SOUTHEAST FROM THE CANADIAN ROCKIES FRI AND ARRIVE OVER
CENTRAL ONTARIO/NORTHERN GREAT LAKES LATE FRIDAY/EARLY SAT. THEN
HEIGHTS ARE PROGGED TO INCREASE ACROSS THE WESTERN CONUS...WITH THE
POTENTIAL FOR A STRONGER WAVE/TROUGH DIGGING INTO THE EASTERN
PACIFIC. THIS COULD RESULT IN SHIFTING THE BUILDING WESTERN CONUS
RIDGE FURTHER EAST LATE IN THE WEEKEND INTO EARLY THE FOLLOWING
WEEK. OUTSIDE OF SOME OCCASIONAL CHANCES FOR SHOWERS IN THE CURRENT
EXTENDED PERIODS...THERE DOES NOT APPEAR TO BE ANY NOTABLE SYSTEMS
POISED TO IMPACT THE REGION. TEMPERATURES WILL ALSO GENERALLY BE IN
THE 60S...HOWEVER WITH INCREASED CLOUDS AND THE WEEKEND SHORTWAVE
SYSTEM...TEMPS COULD STRUGGLE TO WARM BEYOND THE 50S SAT/SUN.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* OCNL PERIODS MVFR CIGS/VIS THROUGH EARLY AFTERNOON...AHEAD OF AN
APCHG WARM FRONT.
* LIGHT WINDS SELY-ELY THROUGH ARND NOON...THEN BECMG SELY AND
INCRG TO 10-12KT.
* WINDS BECMG SSELY DURG AFTERNOON AND INCREASING TO 12G18-20KT
FOLLOWING PASSAGE OF WARM FRONT.
* WINDS BECMG SLY AND INCRG TO 18G25KT OR POSSIBLY HIGHER LATE
EVENING TO LATE NIGHT TONIGHT.
KREIN
//DISCUSSION...UPDATED 12Z...
VERY MOIST AIRMASS CONTINUES TO LIFT NORTH TOWARDS NORTHERN
IL/NORTHWEST IN AIRFIELDS THRU TODAY. LLVL FLOW HAS REMAINED
SOUTHERLY...AND MAY SEE SFC WINDS TURN SLIGHTLY TO SOUTHEASTERLY
FOR A PERIOD OF TIME THRU MID-MORNING. CIGS ARND 900FT AGL AT MANY
SITES...AND THE LATEST INDICATIONS ARE THAT CIGS MAY BE ABLE TO
PUSH TO LOW-END MVFR CONDS EARLIER THAN EXPECTED.
WITH THE CONTINUED FEED OF MOISTURE NORTH TOWARDS TAF SITES IT
APPEARS CIGS WILL STAY DOWN THRU MOST OF THE MORNING. DRIZZLE
WITH POCKETS OF LGT SHRA WILL CONTINUE THIS MORNING...THEN A LULL
IN THE PRECIP LOOKS LIKELY INTO THE AFTN.
GUIDANCE HAS CONTINUED TO FOCUS THE BETTER ORGANIZED SHOWERS TO
HOLD OFF UNTIL AFT 22Z. AT THIS TIME IT APPEARS THE BEST CHANCE
FOR THUNDER WILL BE WELL SOUTH OF THE TAF SITES.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM CONFIDENCE IN CIG/VIS/PCPN TRENDS AND TIMING.
* MEDIUM TO HIGH CONFIDENCE IN WIND DIR/SPEED TRENDS...WITH MEDIUM
CONFIDENCE IN EXACT TIMING.
* HIGH CONFIDENCE THAT ANY THUNDER WILL BE EAST AND SOUTH OF THE
TERMINALS.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT...OCNL -SHRA. MVFR CIGS LIKELY. STRONG NORTH TO
NORTHEAST WINDS POSSIBLE.
WEDNESDAY...OCNL -SHRA. MVFR CIGS PROBABLE...SMALL CHANCE OF IFR
CIGS.
THURSDAY...SMALL CHANCE OF -SHRA...PREDOMINANTLY VFR.
FRIDAY THROUGH SUNDAY...PREDOMINANTLY VFR.
BEACHLER
&&
.MARINE...
219 AM CDT
MAIN CONCERN RESIDES WITH THE WINDS IN THE NEARSHORE FOR
TONIGHT...WHICH APPEARS TO BE BODERLINE SMALL CRAFT CRITERIA. THEN
THE GRADIENT QUICKLY DIMINISHES ARND DAYBREAK TUE...HOWEVER THIS
LOOKS TO ONLY BE TEMPORARY. TUE NGT ONCE THE LOW DRIFTS EAST OF
THE LAKE...THE GRADIENT IS POISED TO QUICKLY RAMP BACK UP.
GUIDANCE CONTINUES TO SUGGEST A PERIOD OF GALES WILL DEVELOP LATE
TUE EVENING THROUGH WED.
LOW PRESSURE EARLY THIS MORNING REMAINS WELL SOUTH OF LAKE
MICHIGAN NEAR CENTRAL OKLAHOMA...HOWEVER THIS LOW IS EXPECTED TO
STEADILY DEEPEN AS IT LIFTS NORTHEAST INTO CENTRAL MISSOURI BY
MID-MORNING. WINDS ACROSS THE SOUTHERN PORTION OF THE LAKE WILL
BEGIN TO INCREASE FROM THE SOUTHEAST...WHICH SHOULD BE ABLE TO
BUILD THE WAVES ALONG THE ILLINOIS NEARSHORE. THE WILDCARD IS THAT
WITH WARMER AIR FLOWING OVER THE LAKE THIS MAY RESULT IN WINDS NOT
EFFECTIVELY REACHING THE SFC. EARLIER GUIDANCE WAS INDICATING THAT
WINDS COULD BE STRONGER...BUT HAVE BEGUN TO BACK OFF FROM THIS FOR
THE SOUTHERN PORTION OF THE LAKE. THEN AS THE LOW DRIFTS EAST OF
THE LAKE...THE GRADIENT QUICKLY INCREASES FROM THE NORTH TO SOUTH
TUESDAY EVENING INTO WEDNESDAY. THIS APPEARS TO BE A FAVORABLE
PERIOD WHEN GALES TO 35KT MAY OCCUR. THE HIGHEST CONFIDENCE IS ON
THE WINDS BEING 30KT. HAVE HELD OFF ON A GALE WATCH AT THIS
TIME...BUT COULD SEE ONE BEING NEEDED FOR TUE NGT/WED. WAVES WILL
EASILY BUILD. THE NORTHERN/CENTRAL PORTIONS OF THE LAKE HAVE THE
BEST CHANCE TO SEE GALE FORCE GUSTS. EXPECT WAVES TO INCREASE
CONSIDERABLY...ESPECIALLY TUESDAY INTO WEDNESDAY AS A NORTHERLY
FETCH OF WINDS CONTINUES FOR AN EXTENDED PERIOD OF TIME. THE LOW
EVENTUALLY FILLS AND GETS KICKED EAST BY ANOTHER SYSTEM MOVING
THROUGH SOUTHERN CANADA.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...NEARSHORE WATERS
UNTIL 4 PM MONDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...10 PM MONDAY TO 5 AM TUESDAY.
DENSE FOG ADVISORY...LMZ080-LMZ366-LMZ565-LMZ567-LMZ669-LMZ671-
LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-
LMZ876-LMZ878 UNTIL 9 PM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1024 AM CDT Mon Oct 13 2014
.UPDATE...
ISSUED AT 1023 AM CDT MON OCT 13 2014
Leading warm front/boundary is steadily lifting northward across
the forecast area, extending roughly along a Quincy to Rantoul
line at 10 am. Visibilities have been steadily improving as the
front moves north, with only isolated areas below 2 miles left.
The big question remains with the potential for severe weather.
Line of storms currently in southeast Missouri extends all the way
into eastern Texas. 0-6km bulk shear already in the 50-60 knot
range along the Illinois/Missouri border and the RAP model shifts
this into central Illinois over the next few hours. Very little
sunshine if any to fuel the fire, with MUCAPE`s only rising into
the 500-1000 J/kg range, but the overall dynamics may be enough to
overcome this limitation. High-res models all agree in a narrow,
fast moving squall line, but have a spread of 2-6 hours in terms
of when the line actually moves through. Latest HRRR brings it as
early as 3 pm around Springfield, ranging to 6 pm with the NSSL
ARW and 8 pm with the 1km NAM nest. The northward movement of the
cells in Missouri would lead some credence to the earlier
solutions.
Have made some timing adjustments to the PoP`s in the grids
through tonight, and also added some mention of severe storms
across the south half of the area late afternoon/early evening.
Temperature trends currently on track.
&&
.SHORT TERM...(Today)
ISSUED AT 342 AM CDT MON OCT 13 2014
High pressure ridge over both east and west coast with a deepening
and slow-moving trof dominating the Plains, moving into the
Midwest. Deepening surface low providing today`s storm system for
the region. Models pretty consistent in depicting this storm in
two main sections...with the frontal convection to the south and the
deformation zone wrapping around the NW side of the low just to
the north. Some issues with the forecast surrounding the placement
of pops to cover the trends with some uncertainty around the
timing and the depth of the dry slot. NAM and GFS all becoming
more pronounced with the dry air in the last run...and the ECMWF
coming into line as well. NSSL WRF even more aggressive with the
dry wedge...also far more showery with regards to the activity
into tonight. Under a slight risk for severe storms today, the
better shear profile to the south with the moderate risk in the
southern tip of the state and western KY...combined with a better
chance for temperature recovery from any showers over the area
this morning. This far north will be tough to scour out the
clouds, though any clearing should be watched closely for
re-energizing ahead of the system... priming for severe weather
activity.
&&
.LONG TERM...(Tonight through Sunday)
ISSUED AT 342 AM CDT MON OCT 13 2014
Models have been very consistent in the last few runs with dropping
the wave into the region and cutting off the 500mb low, parking it
over the region through midweek. Tonight, the storm remains overhead
before wrapping up on itself. Threat for the stronger convection
shifts to the east before midnight... then the pops starting to
lessen with the impact of the dry slot building north into the
state. Exact location of the dry slot adding in some
uncertainty...though the precip after midnight, particularly to the
north and northwest may be dominated with mostly drizzle, but fairly
consistent enough to keep wet and plenty of low clouds through the
early morning hours.
Next couple of days will improve only slightly as the upper low
grows mostly stagnant over the region. Deformation zone starts to
lose structure as the low wraps up on Tuesday and convection from
the front races out ahead of the actual low. Cloudy, gray, showery
and cool conditions continue through Wednesday night under the
persistent cyclonic flow....likely to be dominated by rain without
thunder. Drying out on Thursday as the low finally gets kicked to
the east by another wave diving into the Great Lakes region. ECMWF
pushing a quick short wave into the region late Sun and into
Mon...GFS is dry, so the blend is starting to put some pops into the
forecast. Tempering them for now to low chance with the nature of a
fast short wave in NWrly flow on day 7/8...not a big concern at this
point.
&&
.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
ISSUED AT 540 AM CDT MON OCT 13 2014
LIFR and IFR conditions are expected to continue across all of our
TAF sites thru the period. A warm front was located over southern
Illinois early this morning and is expected to track north of our
area by this afternoon. Along the frontal boundary, scattered
showers and thunderstorms are expected to track north-northeast
this morning with the front and affect all of the TAF locations
before a break in the rain by early this afternoon. North of the
warm front, we have seen areas of dense fog most of the night but
that is expected to gradually lift later this morning as the warm
front shifts to our north.
Our attention will then turn to a squall line that is forecast to
push rapidly northeast out of eastern Missouri this afternoon and
affect areas along and east of I-55. A few of the storms along the
line may be capable of producing strong winds and torrential
rainfall for a short period of time. Current indications suggest
the best timing for this squall line appears to be in the 21z-03z
time frame from southwest to northeast. Once the storms move out,
expect scattered showers from time to time overnight with a
continuation of the low cigs and vsbsy. Surface winds will be
southeast today and increase to between 15 and 25 kts with some
higher gusts possible into this evening before diminishing after
02z from a southeast direction.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Geelhart
SHORT TERM...HJS
LONG TERM...HJS
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS GOODLAND KS
157 PM MDT MON OCT 13 2014
.SHORT TERM...(THIS AFTERNOON THROUGH TUESDAY)
ISSUED AT 127 PM MDT MON OCT 13 2014
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS LARGE CALE
RIDGE BUILDING ACROSS THE WESTERN US INTO THE CENTRAL ROCKIES WITH
CLOSED UPPER LOW OVER EASTERN KS. AT THE SURFACE HIGH PRESSURE IS
BEGINNING TO BUILD INTO NORTHERN AND EASTERN COLORADO WITH A
NORTH-SOUTH PRESSURE GRADIENT IN PLACE OVER WESTERN KS.
WINDS ALOFT ARE ALREADY SHOWING A DOWNWARD TREND...AND AS THE
SURFACE GRADIENT CONTINUES TO WEAKEN WINDS WILL FOLLOW SUIT. WIND
ADVISORY IS MARGINAL...HOWEVER I COULD SEE ANOTHER FEW HOURS WHERE
GUSTS WILL BE AROUND 45 MPH. IT IS CLOSE ENOUGH THAT I DIDNT WANT
TO EXPIRE THE ADVISORY EARLY...SO WILL ALLOW THE ADVISORY TO
CONTINUE UNTIL WE SEE A MUCH MORE DEFINITE DOWNWARD TREND IN WIND
SPEEDS.
WITH CLEAR SKIES...DECREASING WINDS...AND LOW TD VALUES IN THE MID
20S TO LOW 30S WE WILL SEE VERY GOOD RADIATIONAL CONDITIONS
OVERNIGHT. AIR MARI MASS MAY BEGIN TO MODERATE SOME
ALOFT...HOWEVER WE WILL STILL SEE OVERNIGHT LOWS AT LEAST IN THE
MIDDLE 30S. RIVER VALLEYS AND OTHER LOW LYING/SHELTERED LOCATIONS
WILL LIKELY SEE FROST...AND WITH THE POTENTIAL FOR TEMPS TO BE
EVEN COOLER THAN EXPECTED I DECIDED TO ISSUE FROST ADVISORY 06Z-
15Z TUE.
TUESDAY...WITH STRONG RIDGING ALOFT AND HIGH PRESSURE AT THE
SURFACE DRY CONDITIONS WILL CONTINUE THROUGH TUESDAY...AND AIR
MASS WILL SLOWLY MODERATE. HIGHS SHOULD BE SEASONAL WITH VALUES IN
THE UPPER 60S (POSSIBLY LOWER 70S).
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 157 PM MDT MON OCT 13 2014
FOR THE EXTENDED FORECAST...A RATHER BENIGN WEATHER PATTERN SETS UP
IN THE FORM OF A LARGE RIDGE OF HIGH PRESSURE ACROSS THE WESTERN
UNITED STATES. TEMPERATURES THROUGHOUT THE PERIOD ARE EXPECTED TO BE
ABOVE NORMAL. A WEAK COLD FRONT PASSES THROUGH DURING THE DAY
THURSDAY...LEAVING SLIGHTLY COOLER YET MARGINALLY ABOVE NORMAL
TEMPERATURES IN ITS WAKE. NO HAZARDOUS WEATHER IS ANTICIPATED.
AS FOR PRECIPITATION...A DRY FORECAST HAS BEEN ISSUED FOR THE ENTIRE
FORECAST AREA. THE CURRENT GFS RUN AND THE PREVIOUS EUROPEAN MODEL
INDICATED A WEAK DISTURBANCE MOVING THROUGH ON SUNDAY. THIS SYSTEM
WAS PROJECTED TO BRING SOME SHOWERS...POSSIBLY A STORM OR TWO...TO
LOCATIONS SOUTH OF INTERSTATE 70. THE CURRENT EUROPEAN MODEL RUN HAS
BACKED OFF THAT SOLUTION AND...IN AGREEMENT WITH THE CANADIAN
MODEL...HOLDS THE DISTURBANCE UP IN THE SOUTHWESTERN UNITED STATES.
IN COLLABORATION WITH NEIGHBORING OFFICES...DECIDED TO PULL
INITIALIZED CHANCES FOR PRECIPITATION FOR SATURDAY NIGHT THROUGH
MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1129 AM MDT MON OCT 13 2014
VFR CONDITIONS WILL PERSIST THROUGH THE TAF PERIOD AT KGLD AND
KMCK. GUSTY NORTHERLY WINDS WILL CONTINUE AT BOTH TERMINALS BEFORE
SLOWLY DECREASING LATER THIS AFTERNOON AS SURFACE GRADIENT
RELAXES AND HIGH PRESSURE SETTLES INTO THE REGION.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...FROST ADVISORY FROM MIDNIGHT MDT /1 AM CDT/ TONIGHT TO 9 AM MDT
/10 AM CDT/ TUESDAY FOR KSZ001>003-013-014-027-028-041-042.
WIND ADVISORY UNTIL 6 PM MDT /7 PM CDT/ THIS EVENING FOR
KSZ001>004-013>016-027>029-041-042.
CO...FROST ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM MDT TUESDAY FOR
COZ090>092.
WIND ADVISORY UNTIL 6 PM MDT THIS EVENING FOR COZ091-092.
NE...FROST ADVISORY FROM MIDNIGHT MDT /1 AM CDT/ TONIGHT TO 9 AM MDT
/10 AM CDT/ TUESDAY FOR NEZ079>081.
WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NEZ080-081.
&&
$$
SHORT TERM...DR
LONG TERM...RRH
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
128 PM MDT MON OCT 13 2014
.SHORT TERM...(THIS AFTERNOON THROUGH TUESDAY)
ISSUED AT 127 PM MDT MON OCT 13 2014
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS LARGE CALE
RIDGE BUILDING ACROSS THE WESTERN US INTO THE CENTRAL ROCKIES WITH
CLOSED UPPER LOW OVER EASTERN KS. AT THE SURFACE HIGH PRESSURE IS
BEGINNING TO BUILD INTO NORTHERN AND EASTERN COLORADO WITH A
NORTH-SOUTH PRESSURE GRADIENT IN PLACE OVER WESTERN KS.
WINDS ALOFT ARE ALREADY SHOWING A DOWNWARD TREND...AND AS THE
SURFACE GRADIENT CONTINUES TO WEAKEN WINDS WILL FOLLOW SUIT. WIND
ADVISORY IS MARGINAL...HOWEVER I COULD SEE ANOTHER FEW HOURS WHERE
GUSTS WILL BE AROUND 45 MPH. IT IS CLOSE ENOUGH THAT I DIDNT WANT
TO EXPIRE THE ADVISORY EARLY...SO WILL ALLOW THE ADVISORY TO
CONTINUE UNTIL WE SEE A MUCH MORE DEFINITE DOWNWARD TREND IN WIND
SPEEDS.
WITH CLEAR SKIES...DECREASING WINDS...AND LOW TD VALUES IN THE MID
20S TO LOW 30S WE WILL SEE VERY GOOD RADIATIONAL CONDITIONS
OVERNIGHT. AIR MARI MASS MAY BEGIN TO MODERATE SOME
ALOFT...HOWEVER WE WILL STILL SEE OVERNIGHT LOWS AT LEAST IN THE
MIDDLE 30S. RIVER VALLEYS AND OTHER LOW LYING/SHELTERED LOCATIONS
WILL LIKELY SEE FROST...AND WITH THE POTENTIAL FOR TEMPS TO BE
EVEN COOLER THAN EXPECTED I DECIDED TO ISSUE FROST ADVISORY 06Z-
15Z TUE.
TUESDAY...WITH STRONG RIDGING ALOFT AND HIGH PRESSURE AT THE
SURFACE DRY CONDITIONS WILL CONTINUE THROUGH TUESDAY...AND AIR
MASS WILL SLOWLY MODERATE. HIGHS SHOULD BE SEASONAL WITH VALUES IN
THE UPPER 60S (POSSIBLY LOWER 70S).
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 252 AM MDT MON OCT 13 2014
FOR TUESDAY ON THROUGH WEDNESDAY NIGHT...THE ENTIRE FORECAST AREA
WILL SEE A PROLONGED DRY STRETCH OF WEATHER AS BROAD AREA OF HIGH
PRESSURE SHIFTS EAST OF THE ROCKIES ON INTO THE CENTRAL PLAINS.
DURING THIS TIME FRAME DO EXPECT GRADUAL INCREASE IN DAYTIME TEMPS
AS REGION WILL SEE LIMITED CLOUD COVER AND FULL SUNSHINE. LOOKING
FOR TEMPS TO START OFF ON TUESDAY AROUND 70F...THEN INCREASE WELL
INTO THE MID/UPPER 70S BY MIDWEEK. FOR THE OVERNIGHT LOWS
HOWEVER...LACK OF CLOUD COVER WILL ALLOW FOR AMPLE RADIATIONAL
COOLING AND THUS DROP TEMPS DOWN INTO THE 30S TO NEAR 40F.
ZONAL FLOW ALOFT WILL START THE EXTENDED FORECAST PERIOD ON
THURSDAY AS A DRY COLD FRONT AT THE SURFACE MOVES THROUGH THE
HIGH PLAINS REGION. HIGH TEMPERATURES THURSDAY ACROSS THE REGION
WILL RISE BETWEEN THE LOW TO MID 70S...WHICH IS ABOUT 5 DEGREES
ABOVE NORMAL. COOLER AIR WILL SLIDE INTO THE HIGH PLAINS AS A
SURFACE HIGH PRESSURE AND UPPER LEVEL RIDGE BUILDS INTO THE REGION
FRIDAY...BRINGING HIGH TEMPERATURES BACK TO NEAR NORMAL IN THE
UPPER 60S. DRY WEATHER AND SEASONABLE CONDITIONS WILL CONTINUE
THROUGHOUT NEXT WEEKEND. LOW TEMPERATURES THROUGH THE PERIOD
SHOULD STAY ABOVE FREEZING AND NEAR NORMAL WITH LOWS IN THE LOW TO
MID 40S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1129 AM MDT MON OCT 13 2014
VFR CONDITIONS WILL PERSIST THROUGH THE TAF PERIOD AT KGLD AND
KMCK. GUSTY NORTHERLY WINDS WILL CONTINUE AT BOTH TERMINALS BEFORE
SLOWLY DECREASING LATER THIS AFTERNOON AS SURFACE GRADIENT
RELAXES AND HIGH PRESSURE SETTLES INTO THE REGION.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...FROST ADVISORY FROM MIDNIGHT MDT /1 AM CDT/ TONIGHT TO 9 AM MDT
/10 AM CDT/ TUESDAY FOR KSZ001>003-013-014-027-028-041-042.
WIND ADVISORY UNTIL 6 PM MDT /7 PM CDT/ THIS EVENING FOR
KSZ001>004-013>016-027>029-041-042.
CO...FROST ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM MDT TUESDAY FOR
COZ090>092.
WIND ADVISORY UNTIL 6 PM MDT THIS EVENING FOR COZ091-092.
NE...FROST ADVISORY FROM MIDNIGHT MDT /1 AM CDT/ TONIGHT TO 9 AM MDT
/10 AM CDT/ TUESDAY FOR NEZ079>081.
WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NEZ080-081.
&&
$$
SHORT TERM...DR
LONG TERM...JN/MK
AVIATION...DR
AREA FORECAST DISCUSSION...UPDATED
NWS PADUCAH KY
1227 PM CDT Mon Oct 13 2014
.UPDATE...
Issued at 1227 PM CDT MON OCT 13 2014
The AVIATION discussion has been updated for the 18Z TAF issuance.
&&
.SHORT TERM...(Today through Wednesday)
Issued at 350 AM CDT MON OCT 13 2014
Decided not to issue a Flash Flood Watch at this time. The latest
HRRR has the main line into Carter and Ripley counties around 18Z
and to the Mississippi River by 21Z this afternoon. Looking at
current radar mosaics, it appears that the latest HRRR may even be
a bit slow. Anyway, followed it fairly closely in timing the main
band through the area in the PoP grids. This is a bit faster than
the previous forecast.
The main convective band may hang up a bit tonight over the
Pennyrile and southwest Indiana, and that is where the heaviest
rain is likely to fall. Using the latest HPC QPF gives that region
2.5"-3" through tonight, which is below 3 hour FFG. Certainly
could see some nuisance issues, but nothing widespread or
significant is expected based on the QPF and FFG. If the FFG is
lowered after this morning`s rains are processed, then the day
shift can re-evaluate.
The 00Z models and the latest HRRR indicate that some scattered
convection will be possible over much of the area through midday,
but then it should dry out, as the main convective band begins to
move through the region. Still cannot rule out a strong storm
through midday, if they become surface-based late this morning.
Damaging winds and hail would be the primary concern.
Wind fields will increase significantly later this afternoon,
presumably with the main band. However, as the line is pushed
faster to the east, there is some concern that it may outrun the
strongest wind fields. Either way there will be plenty of 0-3km
helicity to support rotating updrafts and the 0-1km shear will be
quite strong. The bottom line is that damaging winds and some
tornadoes will be possible. If a supercell can get going just
ahead of the line or persist within the line, a more significant
damaging wind and tornado threat can be expected.
As for timing, figure that the main line will enter Ripley and
Carter counties near 18Z, and push east of the area just after
06Z. That would result in a 12 hour window for severe weather and
heavy rainfall.
Will have to keep good chance PoPs going throughout the region
Tuesday through Wednesday due to the proximity of the upper low,
and the presence of a weak surface trough. The best coverage of
showers is expected Wednesday as the upper low moves right
overhead.
.LONG TERM...(Wednesday through Sunday)
Issued at 350 AM CDT MON OCT 13 2014
The GFS continues to slow down the departure of the pesky upper
level low that will be with us for most of the early part of this
week. Yesterdays 00Z GFS run indicated that the low would be exiting
on Wednesday and now, todays 00Z run indicates that it will be more
like Wednesday night. The 00Z ECMWF is now very similar to the 00Z
GFS. Therefore, chances for showers will continue Wednesday
night/Thursday but chances will be greatest in the east/northeast.
After this system pulls out of the area, a weak/dry front moves
through the area on Friday, followed by high pressure that will keep
us dry through Sunday. Another system may bring us a chance for more
precipitation on Sunday night, but confidence is not high yet so
will keep chances low.
After one more day in the 60s on Thursday, we should finally see
readings into the 70s on Friday, but cool off a bit on Saturday and
Sunday behind the weak cold front.
&&
.AVIATION...
Issued at 1227 PM CDT MON OCT 13 2014
Numerous showers and thunderstorms will cross the TAF sites from
west to east throughout the first few hours of the period. Some
storms may be severe and will produce locally heavy rainfall. MVFR
cigs/vsbys will prevail will the passage of the storms, however
brief IFR conditions may occur. In the wake of the area of
preciptation, IFR cigs and/or vsbys and patchy drizzle will
prevail through the overnight hours. Conditions should become MVFR
toward the end of the period. Southerly winds at 12-14 knots
gusting to 20-22 knots will drop off to AOB 10 knots overnight,
then pick back up from the south southwest at 10-12 knots with
gusts up to 20 knots after 15-16Z.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...DRS
LONG TERM...CW
AVIATION...JP
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
605 PM EDT MON OCT 13 2014
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 330 PM EDT MON OCT 13 2014
SCATTERED SHOWERS WILL BECOME WIDESPREAD LATER TONIGHT INTO TUESDAY
AS LOW PRESSURE OVER MISSOURI MOVES SLOWLY NORTHEAST THEN STALLS
OVER NORTHERN ILLINOIS. A FEW THUNDERSTORMS AND LOCALLY HEAVY
RAINFALL ARE ALSO POSSIBLE TONIGHT AND TUESDAY.
THE LOW PRESSURE SYSTEM WILL REMAIN STALLED OVER THE SOUTHERN GREAT
LAKES REGION WEDNESDAY AND THURSDAY. SCATTERED SHOWERS WILL CONTINUE
BUT IT WILL REMAIN MILD THROUGH THE REST OF THE WEEK WITH HIGHS IN
THE 60S. A COOL DOWN IS ANTICIPATED FOR SATURDAY.
&&
.UPDATE...
ISSUED AT 605 PM EDT MON OCT 13 2014
I HAVE SIGNIFICANTLY LOWERED THE CHANCE OF RAIN TONIGHT ACROSS
MOST OF THE AREA...ESPECIALLY THROUGH MIDNIGHT. I ALSO EXPUNGED
THE THUNDERSTORM THREAT FROM THE FORECAST TONIGHT. TO KEEP ALL OF
THE FORECAST DETAILS IN SYNC I ALSO LOWERED THE QPF SIGNIFICANTLY
TONIGHT AND FOR THAT MATTER TUESDAY. THE UPDATED FORECAST DOES
MATCH NICELY WITH THE LATEST FORECASTS FROM NEAR BY OFFICES
THROUGH TUESDAY.
MY MOTIVATION FOR DOING ALL THIS UPDATING IS THERE IS A 65 KNOT
LOW LEVEL JET HEADING DUE NORTH TOWARD MKE CURRENTLY. WITH SUCH A
STRONG JET GOING SO FAR WEST OF LOWER MICHIGAN... IT IS KEEPING
THE DECENT MOISTURE FLUX OUT OF THIS AREA. THAT IDEA IS SHOWN
NICELY WITH THE RAP 21Z 1000/850 MOISTURE TRANSPORT VECTORS. THE
BOTTOM LINE IS MOST OF THE RAIN WILL MISS SOUTHWEST MICHIGAN
THROUGH MOST OF THE NIGHT. WE COULD SEE A FEW STRAY SHOWERS OF
COURSE BUT I DO BELIEVE MOST OF THE SHOWERS WILL BE LIGHT TOO.
IT DOES LOOK LIKE A SECOND LOW LEVEL JET IS AIMED AS SOUTH CENTRAL
LOWER MICHIGAN TUESDAY DURING THE DAYLIGHT HOURS... SO WE WILL LIKELY
STILL SEE SOME RAIN WITH THIS SYSTEM BUT NOT NEARLY AS MUCH WAS WE
WERE THINKING EARLIER.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 330 PM EDT MON OCT 13 2014
THE BULK OF THE STORM TOTAL RAIN FROM THIS EVENT FOR SW LWR MI
APPEARS TO OCCUR ON TUESDAY AS THE UPPER LOW DRAWS CLOSER AND THE
OCCLUSION IMPACTS THE AREA.
MODEL TREND OVER THE LAST TWO RUNS HAS BEEN TO LIFT THE HEAVIEST
RAINFALL TONIGHT WITHIN THE TROWAL FARTHER NORTHWEST WHICH
ESSENTIALLY MEANS IT MISSES MOST OF THE CWFA WITH PERHAPS THE
EXCEPTION OF LUDINGTON.
IN FACT MOST MODEL STORM TOTAL RAINFALL SOLUTIONS ACTUALLY SHOW MUCH
OF SW LWR MI IN A RELATIVE MINIMUM AREA OF QPF IN BETWEEN THE
DEFORMATION ZONE TO THE NORTHWEST AND THE STRONG CONVECTION AHEAD OF
THE COLD FRONT TO THE SOUTH.
THAT SAID...WE SHOULD STILL SEE WIDESPREAD AMOUNTS NEAR AN INCH WITH
LOCALLY AS MUCH AS TWO INCHES. THIS SHOULD NOT CAUSE TOO MUCH OF
A PROBLEM ALTHOUGH WHERE HEAVY RAIN PERSISTS SOME PONDING OF WATER IS
POSSIBLE ESPECIALLY WHERE LEAVES CLOG STORM DRAINS.
AS FAR AS THE THUNDERSTORM THREAT... THERE IS PLENTY OF DEEP LAYER
SHEAR AVAILABLE BUT INSTABILITY IS LIMITED WITH GENERALLY 500 J/KG
OR LESS OF MU CAPE AVAILABLE. THE COVERAGE OF STORMS SHOULD BE
ISOLATED TO SCATTERED TONIGHT AND TUES. THE THING TO WATCH WILL BE
THE 60 KNOT SOUTHERLY LOW LEVEL JET WHICH COMES IN TONIGHT. THIS
COULD LEAD TO SOME RATHER GUSTY SOUTH TO NORTH MOVING SHOWERS IN THE
WARM SECTOR.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 330 PM EDT MON OCT 13 2014
MOST OF THE EXTENDED PERIOD WILL REMAIN UNSETTLED AS A SLOW MOVING
UPPER LOW JUST NORTH OF THE GREAT LAKES MERGES WITH A DIGGING
NORTHERN STREAM TROUGH BEFORE IT FINALLY MOVES EAST. CYCLONIC FLOW
AND SOME LAKE CONTRIBUTION OF MOISTURE SUPPORTS KEEPING CHANCE OR
SLIGHT CHANCE POPS GOING FOR EACH PERIOD FROM THURSDAY THROUGH
SATURDAY. SHORTWAVE RIDGING ON SATURDAY NIGHT AND SUNDAY SHOULD
FINALLY DRY THINGS OUT. TEMPERATURES SHOULD BE MODERATED BY THE
CONTINUOUS CLOUD COVER UNTIL SATURDAY NIGHT AND SUNDAY NIGHT...WHEN
CLEARING WILL ALLOW TEMPS TO DROP INTO THE 30S IN MOST PLACES.
THE FLOW BECOMES HIGHLY AMPLIFIED EARLY NEXT WEEK WITH A DEEP TROUGH
AXIS OVER THE NE CONUS AND A SHARP RIDGE OVER THE PLAINS. THERE
COULD BE SOME SHOWERS ON MONDAY AS A NORTHERN STREAM SHORTWAVE
TROUGH DIGS SOUTH THROUGH THE GREAT LAKES...BUT THE MODEL SOUNDINGS
SHOW A LOT OF DRY AIR AT MID LEVELS...SO WENT WITH A DRY FORECAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 142 PM EDT MON OCT 13 2014
ALTHOUGH IFR IS EXPECTED MUCH OF THE TIME...CONDITIONS WILL VARY
WIDELY FROM MVFR TO IFR AND LIFR TONIGHT AND TUESDAY AS LOW CLOUDS
AND FOG OCCASIONALLY LIFT. EXPECT SOME SCATTERED SHOWERS THIS
AFTERNOON BUT THE STEADY RAIN ALONG WITH SOME THUNDERSTORMS SHOULD
HOLD OFF UNTIL LATER TONIGHT. THE BEST CHANCE FOR THUNDERSTORMS
WILL BE ACROSS SOUTHEAST LOWER MICHIGAN...INCLUDING JXN ON
TUESDAY MORNING.
WINDS WILL BE SOUTH TO SOUTHEAST AROUND 10 KNOTS THIS AFTERNOON.
SOME GUSTS TO 20 KNOTS ARE POSSIBLE LATE THIS EVENING AS STRONGER
WINDS FROM ABOVE REACH THE GROUND.
&&
.MARINE...
ISSUED AT 330 PM EDT MON OCT 13 2014
WHILE THE WINDS WILL BE ON THE INCREASE TONIGHT AS THE LOW LEVEL JET
COMES INTO THE AREA... THE SFC WINDS WILL HAVE A BIT OF AN OFFSHORE
COMPONENT. THIS WILL KEEP THE WAVE HEIGHTS DOWN NEAR THE COAST BUT
DESPITE THAT THE WIND SPEEDS ALONE MAY BECOME SUFFICIENT ENOUGH TO
WARRANT A SMALL CRAFT ADVISORY LATER TONIGHT. WILL HOLD OFF FOR NOW.
WEB CAMS SHOW THAT FOG IS NOT A MAJOR ISSUE ALONG THE SW LWR MI
COASTLINE AND WITH THE WINDS INCREASING TONIGHT SEE NO NEED FOR A
MARINE DENSE FOG ADVISORY AT THIS TIME.
&&
.HYDROLOGY...
ISSUED AT 330 PM EDT MON OCT 13 2014
STORM TOTAL QPF AMOUNTS ARE FORECAST TO BE LESS THAN PREVIOUS
THINKING. GENERALLY AROUND A HALF INCH TO 2 INCHES IS EXPECTED. MOST
LOCATIONS WILL SEE LESS THAN AN INCH AND A HALF...WITH HIGHER
AMOUNTS POSSIBLE TOWARD LUDINGTON. THE TREND IN THE 12Z MODELS IS TO
PUSH THE SLOW-MOVING DEFORMATION BAND OF MODERATE TO HEAVY RAINFALL
TO THE NORTHWEST. MOST OF THE RAINFALL IS EXPECTED TO FALL AFTER 00Z
TUESDAY.
RIVER FLOODING IS NOT EXPECTED...ALTHOUGH AREA RIVERS AND STREAMS
COULD RISE SHARPLY ON TUESDAY. CURRENT STREAMFLOW IN THE GRAND AND
KALAMAZOO RIVER BASINS IS RUNNING ABOVE NORMAL. THERE COULD ALSO BE
BRIEF MINOR URBAN FLOODING AND PONDING OF WATER IN LOW-LYING AREAS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...OSTUNO
AVIATION...OSTUNO
HYDROLOGY...EBW
MARINE...MEADE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
430 PM EDT MON OCT 13 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 429 PM EDT MON OCT 13 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A SHARP TROF ACROSS THE
CNTRL CONUS WITH A STRONG SHORTWAVE IN THE BASE OF THE TROF
BECOMING INCREASINGLY SEPARATED FROM THE FLOW IN THE NRN PORTION OF
THE TROF. THE SHARP TROF HAS TAPPED ABUNDANT MOISTURE AS ANALYSIS OF
12Z RAOBS SHOWED PRECIPITABLE WATER UP TO AROUND 1 INCH ACROSS UPPER
MI WHICH IS 175-200PCT OF NORMAL. RESULT HAS BEEN LOW CLOUDS
DOMINATING THIS AFTN. SOME -DZ/-SHRA/SPRINKLES EARLIER TODAY HAVE
ENDED...AND SO FAR THE AFTN HAS BEEN DRY.
TONIGHT INTO TUE...FLOW IN THE UPSTREAM TROF WILL CONTINUE TO
SEPARATE WHICH RESULTS IN THE SRN PORTION DEVELOPING INTO A CLOSED
LOW OVER THE MID MISSISSIPPI VALLEY. AS THE NRN PORTION
SEPARATES...A WELL-DEFINED JET STREAK WILL DEVELOP FROM NRN ONTARIO
INTO QUEBEC TONIGHT...PLACING THE UPPER LAKES UNDER HEALTHY UPPER
DIVERGENCE IN THE RIGHT ENTRANCE OF JET. DOWN BELOW...A RIBBON OF
STRONG LOW-MID LEVEL FRONTOGENESIS DEVELOPS ACROSS THE FCST AREA.
WITH PRECIPITABLE WATER INCREASING UP TO AROUND 1.5 INCHES (NEAR
250PCT OF NORMAL) ACROSS THE FAR SE FCST AREA NEAR LAKE MI...STRONG
UPPER DIVERGENCE/FRONTOGENESIS SHOULD RESULT IN A SOLID AREA OF MDT
TO LOCALLY HVY RAINFALL SPREADING NNE ACROSS ROUGHLY THE E HALF OF
THE FCST AREA TONIGHT. BULK OF PCPN FALLS TONIGHT...BUT INCLUDING
LINGERING PCPN TUE...EXPECT PCPN AMOUNTS OF 1 INCH OR MORE FROM
MARQUETTE/DICKINSON COUNTIES EASTWARD WITH TOTALS OF 1.5 TO PERHAPS
2 INCHES TOWARD LAKE MICHIGAN. TYPICAL FOR THESE TYPE OF PCPN EVENTS
WHICH HAVE A STRONG FRONTOGENESIS COMPONENENT...THERE SHOULD BE A
FAIRLY SHARP W EDGE TO THE PCPN AREA. EXAMINATION OF THE NUMEROUS
AVBL MODELS INDICATES THAT THE WRN EDGE OF THE PCPN AREA WILL
PROBABLY BE JUST W OF UPPER MI. SO...WHILE PCPN AMOUNTS WILL TAIL
OFF QUICKLY WESTWARD...LIKELY TO CATEGORICAL POPS WILL BE CARRIED TO
THE WRN EDGE OF UPPER MI.
WITH UPPER JET ACROSS NRN ONTARIO SHIFTING E ALONG WITH THE RIBBON
OF STRONG LOW-MID LEVEL FRONTOGENESIS...PCPN WILL DIMINISH FROM W TO
E TUE MORNING AND WILL END OVER THE W. HOWEVER...DEEP LAYER FORCING
REMAINS OVER MUCH OF UPPER MI THRU THE DAY...SO PLAN TO MAINTAIN A
MENTION OF PCPN THRU THE AFTN OVER THE CNTRL AND E...WITH HIGHEST
POPS TOWARD LAKE MI. AN UPPER JET STREAK ON THE E SIDE OF THE MID
LEVEL LOW CENTERED OVER THE MID MISSISSIPPI VALLEY WILL BE ALIGNED
FROM INDIANA UP LAKE MI/WRN LWR MI BY LATE IN THE DAY. UPPER
DIVERGENCE IN THE LEFT EXIT OF THIS JET STREAK WILL LIKELY SUPPORT
ANOTHER AREA OF PCPN THAT MAY BEGIN TO SPREAD INTO SRN PORTIONS OF
UPPER MI LATE IN THE DAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 414 PM EDT MON OCT 13 2014
TUE NIGHT THROUGH THU...AS THE MID/UPPER LEVEL LOW WOBBLES
THROUGH ILLINOIS...THE 12Z GFS AND ESPECIALLY THE 12Z ECMWF HAVE
TRENDED FARTHER TO THE NORTHWEST WITH THE STRONGER 700-300 MB
QVECTOR CONV AHEAD OF A SHRTWV ON THE NRN FLANK OF THE LOW WHILE THE
NAM WAS AN OUTLIER IN KEEPING MOST OF THE CWA DRY. EVEN THOUGH THERE
IS LINGERING UNCERTAINTY WITH THE EVOLUTION OF THE SYSTEM...MODELS
CONSENSUS SUGGESTS THAT HIGHER POPS AND QPF ARE WARRANTED ACROSS THE
CENTRAL AND EAST. RAIN CHANCES WILL ALSO LINGER INTO WED NIGHT AND
THU ACROSS THE EAST HALF OF THE CWA AS THE ECMWF/GFS REMAIN FAR
ENOUGH TO THE WEST SO THAT ADDITIONAL SHORTWAVES ROTATING AROUND THE
LOW BRING POTENTIAL FOR PERIODS OF LIGHT SHOWERS.
THU NIGHT INTO SAT...WITH AN AMPLIFIED PATTERN DEVELOPING...THE WPC
PREFERRED ECMWF SUGGESTS THAT THE WRN RIDGE WILL ALLOW THE NRN
PLAINS TROUGH TO MERGE WITH THE GREAT LAKES LOW AND PERSIST INTO
SATURDAY. AS THE SFC LOW MOVES INTO NE ONTARIO TO NEAR JAMES BAY NW
WINDS AND CAA WILL TAKE OVER BRINGING IN COOLER AIR AND THE
POTENTIAL FOR SHOWERS AS DEEPER MOISTURE PREVAILS. ENOUGH COLD AIR
WILL MOVE IN BY FRI NIGHT INTO SAT FOR LAKE ENHANCED RAIN POTENTIAL
FOR LOCATIONS FAVORED BY NW OR NNW FLOW.
SUN-MON...THE GFS/GEFS/ECMWF SUGGEST THAT THE TROUGH WILL SLIDE FAR
ENOUGH EAST TO REDUCE RAIN CHANCES WHILE NNW MID LEVEL LOW LINGERS.
TEMPS SHOULD REMAIN BELOW NORMAL WITH HIGHS IN THE MID TO UPPER 40S
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 122 PM EDT MON OCT 13 2014
WITH ABUNDANT MOISTURE NOW OVER THE AREA....EXPECT GENERALLY LOW
MVFR TO IFR CONDITIONS TO PREVAIL TODAY AT KIWD/KCMX/KSAW AHEAD OF
AN APPROACHING COLD FRONT. COLD FRONT WILL MOVE ACROSS THE AREA
DURING THE AFTN/EVENING...RESULTING IN WINDS BECOMING N TO NE. AT
THE SAME TIME...WIDESPREAD RAIN NOW ORGANIZING AND LIFTING NNE THRU
THE MID MISSISSIPPI VALLEY WILL OVERSPREAD THE AREA TONIGHT. UPSLOPE
WIND AND RAIN WILL RESULT IN IFR CONDITIONS AT KCMX AND LIFR AT
KIWD/KSAW AS WIND DIRECTION WILL BE A MORE IDEAL UPSLOPE DIRECTION
AT THOSE TERMINALS. EXPECT HEAVIEST RAINFALL AND MORE RESTRICTED VIS
AT KSAW. RAIN WILL END W TO E TUE MORNING/EARLY AFTN. INFLUX OF
DRIER AIR WILL ALLOW KIWD/KCMX TO IMPROVE TO MVFR.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 429 PM EDT MON OCT 13 2014
WEAK PRES GRADIENT AND LIGHT WINDS MOSTLY UNDER 10KT WILL BE THE
RULE INITIALLY TONIGHT. THEN...AS LOW PRESSURE OVER SW MISSOURI
SLOWLY LIFTS NE...N TO NE WINDS WILL INCREASE LATE TONIGHT INTO TUE.
EXPECT N TO NE WINDS UP TO 20KT ON WRN LAKE SUPERIOR AND UP TO 25KT
ON ERN LAKE SUPERIOR. THE LOW WILL THEN WEAKEN AS IT DRIFTS NE
ACROSS THE GREAT LAKES REGION WED/THU...ALLOWING WINDS TO DIMINISH.
WINDS SHOULD BE UNDER 10KT BY THU. ANOTHER LOW PRESSURE SYSTEM
TRACKING ACROSS SRN CANADA THU WILL THEN MERGE WITH THE REMNANT
GREAT LAKES LOW ON FRI IN THE VICINITY OF JAMES BAY. THIS WILL
RESULT IN W TO NW WINDS INCREASING INTO THE 15-25KT RANGE ON FRI AND
CONTINUING INTO SAT AS THE LOW MOVES LITTLE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLB
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
415 PM EDT MON OCT 13 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 404 AM EDT MON OCT 13 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEPENING UPR TROF
OVER THE CENTRAL CONUS AS POTENT SHRTWV DIGS INTO THE SRN PLAINS.
WITHIN THIS LARGER TROF...THERE IS A WEAKER SHRTWV LIFTING NEWD THRU
THE NRN PLAINS...AND SOME ISOLD-SCT SHOWERS IN THE LARGER SCALE
ISENTROPIC ASCENT/SW FLOW/AREA OF H85-5 QVECTOR CNVGC BTWN THAT
SHRTWV AND DEPARTING HI PRES OVER NEW ENGLAND HAVE MOVED INTO THE
UPR LKS DESPITE VERY DRY H7-9 LYR SHOWN ON THE 00Z GRB RAOB. THERE
IS ANOTHER AREA OF SHOWERS OVER MN UNDER THE SHARPER DEEP LYR
QVECTOR CNVGC CLOSER TO THE SHRTWV LIFTING NEWD IN THE NRN
PLAINS...BUT THERE IS LTL IN THE WAY OF PCPN BTWN THE ACTIVITY IN
MN/THE UPR LKS AND MORE WDSPRD SHRA/TS IN THE SCENTRAL PLAINS
ASSOCIATED WITH DEEPER SHRTWV IN THAT AREA DESPITE PWATS AS HI AS AN
INCH /UP TO 150 PCT OF NORMAL/ AT QUAD CITIES IOWA.
MAIN FCST CONCERNS THRU TNGT ARE FOCUSED ON POPS. STILL LOOKS LIKE
THE MOST WDSPRD...HEAVY RA WL IMPACT THE E HALF OF UPR MI TNGT
CLOSER TO RIBBON OF HIER PWAT/DVLPG FGEN. PER NCEP GUIDANCE...
FOLLOWED THE 00Z NAM/12Z ECMWF MOST CLOSELY FOR FCST DETAILS.
TODAY...AREA OF DEEPER MSTR/SOMEWHAT SHARPER ISENTROPIC ASCENT/AXIS
OF H85-5 QVECTOR CNVGC IS FCST TO MOVE NEWD AND PASS OUT OF UPR MI
BY NOON AND GIVE WAY TO SOME WEAK DEEP LYR QVECTOR DVGC/DRYING ABV
H7...SO EXPECT THE ISOLD-SCT SHOWERS IMPACTING UPR MI TO DIMINISH IN
THE AFTN. MEANWHILE...AS SHRTWV IN THE NRN PLAINS/ACCOMPANYING
QVECTOR CNVGC CONTINUES TO THE NE AND INTO NW ONTARIO...AREA OF
SHOWERS IN MN WL FOLLOW AND TEND TO MISS ALL BUT WRN LK SUP. BUT
WITH PERSISTENT SLY FLOW OF MOISTER AIR TO THE S...EXPECT OVERCAST
SKIES DESPITE THE DIMINISHING PCPN TREND. LATE IN THE DAY TOWARD 00Z
TUE...COMBINATION OF INCRSG UPR DVGC IN RRQ OF 100KT H3 JET MAX
SHIFTING INTO NW ONTARIO WITH NRN SHRTWV...AREA OF DEEP LYR QVECTOR
CNVGC APRCHG FM THE S AND ARRIVAL OF AXIS OF H85-7 FGEN IN COMMA
TAIL OF DEPARTING SHRTWV IN ONTARIO WL BRING A RETURN OF HIER POPS
TO AREAS NEAR THE WI BORDER/SCENTRAL.
TNGT...DEEP SSW FLOW E OF UPR TROF AXIS IS PROGGED TO LIFT PWAT TO
NEAR 1.5 INCHES OVER THE FAR SE CWA NEAR LK MI...NEARLY 250 PCT OF
NORMAL. IN CONCERT WITH UPR DVGC IN RRQ OF INTENSIFYING H3 JET MAX
IN NW ONTARIO AND AXIS OF SHARP H85-7 FGEN/ISENTROPIC ASCENT ON THE
300-305K SFCS /ABOUT H8-7/ NEAR FRONTAL ZN THAT IS FCST TO IMPACT
THE SE PORTION OF THE FA...EXPECT CATEGORICAL POPS/SOME MDT TO AT
TIMES HEAVY RA IN THIS AREA. THE WRN EXTENT OF THE HIER POPS/
HEAVIER RA IS SOMEWHAT IN QUESTION BECAUSE THE MAIN CUTOFF LO
ASSOCIATED WITH THE MORE VIGOROUS SRN BRANCH SHRTWV AND ACCOMPANYING
SHARPER DEEP LYR QVECTOR CNVGC ARE PROGGED TO STAY S OF THE UPR
LKS...WITH UPR DVGC THE MAIN FORCING MECHANISM FOR PCPN TO THE W.
THE 00Z NAM/12Z ECMWF SHOW SUFFICIENT DRYING OVER THE W IN THE WAKE
OF THE SHRTWV MOVING INTO ONTARIO AND SO FAR W OF THE FRONTAL ZN TO
SUPPORT LTL IF ANY PCPN OVER THE FAR W...SO TENDED TO LOWER POPS IN
THIS AREA. OTRW...ADDED SOME FOG OVER THE NCENTRAL WITH UPSLOPE NE
FLOW AND ACRS THE E WHERE THE PWAT IS FCST SO HI.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 414 PM EDT MON OCT 13 2014
TUE NIGHT THROUGH THU...AS THE MID/UPPER LEVEL LOW WOBBLES
THROUGH ILLINOIS...THE 12Z GFS AND ESPECIALLY THE 12Z ECMWF HAVE
TRENDED FARTHER TO THE NORTHWEST WITH THE STRONGER 700-300 MB
QVECTOR CONV AHEAD OF A SHRTWV ON THE NRN FLANK OF THE LOW WHILE THE
NAM WAS AN OUTLIER IN KEEPING MOST OF THE CWA DRY. EVEN THOUGH THERE
IS LINGERING UNCERTAINTY WITH THE EVOLUTION OF THE SYSTEM...MODELS
CONSENSUS SUGGESTS THAT HIGHER POPS AND QPF ARE WARRANTED ACROSS THE
CENTRAL AND EAST. RAIN CHANCES WILL ALSO LINGER INTO WED NIGHT AND
THU ACROSS THE EAST HALF OF THE CWA AS THE ECMWF/GFS REMAIN FAR
ENOUGH TO THE WEST SO THAT ADDITIONAL SHORTWAVES ROTATING AROUND THE
LOW BRING POTENTIAL FOR PERIODS OF LIGHT SHOWERS.
THU NIGHT INTO SAT...WITH AN AMPLIFIED PATTERN DEVELOPING...THE WPC
PREFERRED ECMWF SUGGESTS THAT THE WRN RIDGE WILL ALLOW THE NRN
PLAINS TROUGH TO MERGE WITH THE GREAT LAKES LOW AND PERSIST INTO
SATURDAY. AS THE SFC LOW MOVES INTO NE ONTARIO TO NEAR JAMES BAY NW
WINDS AND CAA WILL TAKE OVER BRINGING IN COOLER AIR AND THE
POTENTIAL FOR SHOWERS AS DEEPER MOISTURE PREVAILS. ENOUGH COLD AIR
WILL MOVE IN BY FRI NIGHT INTO SAT FOR LAKE ENHANCED RAIN POTENTIAL
FOR LOCATIONS FAVORED BY NW OR NNW FLOW.
SUN-MON...THE GFS/GEFS/ECMWF SUGGEST THAT THE TROUGH WILL SLIDE FAR
ENOUGH EAST TO REDUCE RAIN CHANCES WHILE NNW MID LEVEL LOW LINGERS.
TEMPS SHOULD REMAIN BELOW NORMAL WITH HIGHS IN THE MID TO UPPER 40S
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 122 PM EDT MON OCT 13 2014
WITH ABUNDANT MOISTURE NOW OVER THE AREA....EXPECT GENERALLY LOW
MVFR TO IFR CONDITIONS TO PREVAIL TODAY AT KIWD/KCMX/KSAW AHEAD OF
AN APPROACHING COLD FRONT. COLD FRONT WILL MOVE ACROSS THE AREA
DURING THE AFTN/EVENING...RESULTING IN WINDS BECOMING N TO NE. AT
THE SAME TIME...WIDESPREAD RAIN NOW ORGANIZING AND LIFTING NNE THRU
THE MID MISSISSIPPI VALLEY WILL OVERSPREAD THE AREA TONIGHT. UPSLOPE
WIND AND RAIN WILL RESULT IN IFR CONDITIONS AT KCMX AND LIFR AT
KIWD/KSAW AS WIND DIRECTION WILL BE A MORE IDEAL UPSLOPE DIRECTION
AT THOSE TERMINALS. EXPECT HEAVIEST RAINFALL AND MORE RESTRICTED VIS
AT KSAW. RAIN WILL END W TO E TUE MORNING/EARLY AFTN. INFLUX OF
DRIER AIR WILL ALLOW KIWD/KCMX TO IMPROVE TO MVFR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 357 AM EDT MON OCT 13 2014
A WEAKENING PRESSURE GRADIENT ACROSS THE AREA WILL LEAD TO WINDS
WILL DROPPING BELOW 10KT ACROSS THE LAKE BY THIS AFTERNOON. AS A LOW
PRESSURE SYSTEM SLOWLY LIFTS NE...WINDS WILL BECOME N TO NE TONIGHT
AND WILL INCREASE LATE. TUE AND TUE NIGHT...EXPECT N TO NE WINDS UP
TO 20KT ON WRN LAKE SUPERIOR AND UP TO 25KT ON ERN LAKE SUPERIOR.
THE LOW WILL THEN WEAKEN AS IT DRIFTS NE ACROSS THE GREAT LAKES
REGION WED/THU...ALLOWING WINDS TO DIMINISH. WINDS SHOULD BE UNDER
10KT BY THU. ANOTHER LOW PRESSURE SYSTEM TRACKING ACROSS SRN CANADA
THU WILL THEN MERGE WITH THE REMNANT GREAT LAKES LOW ON FRI IN THE
VICINITY OF JAMES BAY. THIS WILL RESULT IN INCREASING W TO NW INTO
THE 15-25KT RANGE ON FRI.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLB
AVIATION...ROLFSON
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
122 PM EDT MON OCT 13 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 404 AM EDT MON OCT 13 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEPENING UPR TROF
OVER THE CENTRAL CONUS AS POTENT SHRTWV DIGS INTO THE SRN PLAINS.
WITHIN THIS LARGER TROF...THERE IS A WEAKER SHRTWV LIFTING NEWD THRU
THE NRN PLAINS...AND SOME ISOLD-SCT SHOWERS IN THE LARGER SCALE
ISENTROPIC ASCENT/SW FLOW/AREA OF H85-5 QVECTOR CNVGC BTWN THAT
SHRTWV AND DEPARTING HI PRES OVER NEW ENGLAND HAVE MOVED INTO THE
UPR LKS DESPITE VERY DRY H7-9 LYR SHOWN ON THE 00Z GRB RAOB. THERE
IS ANOTHER AREA OF SHOWERS OVER MN UNDER THE SHARPER DEEP LYR
QVECTOR CNVGC CLOSER TO THE SHRTWV LIFTING NEWD IN THE NRN
PLAINS...BUT THERE IS LTL IN THE WAY OF PCPN BTWN THE ACTIVITY IN
MN/THE UPR LKS AND MORE WDSPRD SHRA/TS IN THE SCENTRAL PLAINS
ASSOCIATED WITH DEEPER SHRTWV IN THAT AREA DESPITE PWATS AS HI AS AN
INCH /UP TO 150 PCT OF NORMAL/ AT QUAD CITIES IOWA.
MAIN FCST CONCERNS THRU TNGT ARE FOCUSED ON POPS. STILL LOOKS LIKE
THE MOST WDSPRD...HEAVY RA WL IMPACT THE E HALF OF UPR MI TNGT
CLOSER TO RIBBON OF HIER PWAT/DVLPG FGEN. PER NCEP GUIDANCE...
FOLLOWED THE 00Z NAM/12Z ECMWF MOST CLOSELY FOR FCST DETAILS.
TODAY...AREA OF DEEPER MSTR/SOMEWHAT SHARPER ISENTROPIC ASCENT/AXIS
OF H85-5 QVECTOR CNVGC IS FCST TO MOVE NEWD AND PASS OUT OF UPR MI
BY NOON AND GIVE WAY TO SOME WEAK DEEP LYR QVECTOR DVGC/DRYING ABV
H7...SO EXPECT THE ISOLD-SCT SHOWERS IMPACTING UPR MI TO DIMINISH IN
THE AFTN. MEANWHILE...AS SHRTWV IN THE NRN PLAINS/ACCOMPANYING
QVECTOR CNVGC CONTINUES TO THE NE AND INTO NW ONTARIO...AREA OF
SHOWERS IN MN WL FOLLOW AND TEND TO MISS ALL BUT WRN LK SUP. BUT
WITH PERSISTENT SLY FLOW OF MOISTER AIR TO THE S...EXPECT OVERCAST
SKIES DESPITE THE DIMINISHING PCPN TREND. LATE IN THE DAY TOWARD 00Z
TUE...COMBINATION OF INCRSG UPR DVGC IN RRQ OF 100KT H3 JET MAX
SHIFTING INTO NW ONTARIO WITH NRN SHRTWV...AREA OF DEEP LYR QVECTOR
CNVGC APRCHG FM THE S AND ARRIVAL OF AXIS OF H85-7 FGEN IN COMMA
TAIL OF DEPARTING SHRTWV IN ONTARIO WL BRING A RETURN OF HIER POPS
TO AREAS NEAR THE WI BORDER/SCENTRAL.
TNGT...DEEP SSW FLOW E OF UPR TROF AXIS IS PROGGED TO LIFT PWAT TO
NEAR 1.5 INCHES OVER THE FAR SE CWA NEAR LK MI...NEARLY 250 PCT OF
NORMAL. IN CONCERT WITH UPR DVGC IN RRQ OF INTENSIFYING H3 JET MAX
IN NW ONTARIO AND AXIS OF SHARP H85-7 FGEN/ISENTROPIC ASCENT ON THE
300-305K SFCS /ABOUT H8-7/ NEAR FRONTAL ZN THAT IS FCST TO IMPACT
THE SE PORTION OF THE FA...EXPECT CATEGORICAL POPS/SOME MDT TO AT
TIMES HEAVY RA IN THIS AREA. THE WRN EXTENT OF THE HIER POPS/
HEAVIER RA IS SOMEWHAT IN QUESTION BECAUSE THE MAIN CUTOFF LO
ASSOCIATED WITH THE MORE VIGOROUS SRN BRANCH SHRTWV AND ACCOMPANYING
SHARPER DEEP LYR QVECTOR CNVGC ARE PROGGED TO STAY S OF THE UPR
LKS...WITH UPR DVGC THE MAIN FORCING MECHANISM FOR PCPN TO THE W.
THE 00Z NAM/12Z ECMWF SHOW SUFFICIENT DRYING OVER THE W IN THE WAKE
OF THE SHRTWV MOVING INTO ONTARIO AND SO FAR W OF THE FRONTAL ZN TO
SUPPORT LTL IF ANY PCPN OVER THE FAR W...SO TENDED TO LOWER POPS IN
THIS AREA. OTRW...ADDED SOME FOG OVER THE NCENTRAL WITH UPSLOPE NE
FLOW AND ACRS THE E WHERE THE PWAT IS FCST SO HI.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 357 AM EDT MON OCT 13 2014
TUE WILL SEE DECREASING RAIN CHANCES AS AN FGEN BAND ALONG AN
INVERTED SFC TROUGH MOVES E OF THE CWA. MODELS VARY ON EXACTLY WHERE
THE BAND WILL BE AT IN THE MORNING AND HOW FAST IT WILL MOVE E...BUT
AT LEAST FAR NWRN UPPER MI /FROM IWD THROUGH THE KEWEENAW/ WILL BE
DRY ALL DAY PER THE FARTHER W 00Z/13 GFS SOLUTION. THE 12Z/12 ECMWF
ONLY HAS 0.02 INCHES OF RAIN IN THE MORNING AT ERY. THE 00Z/13 NAM
TAKES THE MIDDLE GROUND...WHICH MAKES IT PREFERABLE GIVEN A LACK OF
PREFERENCE FOR THE GFS VS THE ECMWF. ALL THREE OF THESE MODELS HAVE
THE CWA DRY FROM 18Z THROUGH THE REST OF TUE.
AN ADDITIONAL CONCERN...ESPECIALLY DURING THE TUESDAY INTO TUESDAY
NIGHT TIME PERIOD IS THE POSSIBILITY FOR LARGE WAVES TO DEVELOP ON
THE TIGHTER PRESSURE GRADIENT ALONG THE INVERTED TROUGH. THESE WAVES
WOULD DEVELOP ON GUSTY NORTH TO NORTHEASTERLY WINDS....ALLOWING
WAVES TO REACH AROUND 8 FEET. THIS COULD CAUSE MINOR BEACH EROSION
ALONG THE MARQUETTE AND ALGER COUNTY SHORELINES.
THE ECMWF AND NAM KEEP THE CWA DRY FOR THE MOST PART TUE NIGHT
THROUGH WED WHILE THE GFS BRINGS LIGHT QPF AMOUNTS BACK INTO THE FAR
SERN CWA THROUGH THAT PERIOD. THE REASON FOR THE DISCREPANCY IS THAT
THE GFS SHIFTS THE UPPER LOW FROM CENTRAL IL TO SRN MI WHILE THE
OTHER MODELS KEEP IT OVER IL. BECAUSE OF THIS...THE ECMWF/NAM KEEP
THE UPPER RIDGE EXTENDING N OF THE UPPER LOW ACROSS THE CWA...WHICH
KEEPS THE AIRMASS MUCH DRIER AND FORCING FARTHER S. OPTED TO LOWER
POPS SOME DURING THE PERIOD TO ACCOUNT FOR THE DRIER TREND IN
GUIDANCE. AS HEIGHTS RISE DUE TO THE UPPER RIDGE MOVING N OF THE LOW
AND THE LOW ITSELF FILLING...THE AIRMASS WARMS PRETTY CONSIDERABLY.
850MB TEMPS AT 12Z TUE LOOK TO RANGE FROM 4C W TO 8C E...BUT
INCREASE TO AROUND 11 C OVER THE ENTIRE AREA BY 00Z THU.
DETAILS ARE MUCH LESS CERTAIN AFTER WED...BUT OVERALL THE MODELS
SHOW THE UPPER LOW LIFTING QUICKLY N AND MERGING WITH AN INCOMING
TROUGH THAT DEEPENS INTO A CLOSED LOW /OR AT LEAST A DEEP TROUGH/ AS
IT MOVES THROUGH THE REGION FRI AND SAT. CANNOT GET TOO SPECIFIC AT
THIS POINT GIVEN LACK OF CONFIDENCE...BUT CHANCES FOR PRECIP WILL BE
HIGHER WED NIGHT INTO SAT. A COLD FRONT MOVING THROUGH THU NIGHT OR
FRI WILL BRING COOLER CONDITIONS FRI THROUGH THE WEEKEND. MODELS
HAVE THEN BEEN TRENDING DRIER FOR SUN...SO WILL REFLECT THAT IN THE
FORECAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 122 PM EDT MON OCT 13 2014
WITH ABUNDANT MOISTURE NOW OVER THE AREA....EXPECT GENERALLY LOW
MVFR TO IFR CONDITIONS TO PREVAIL TODAY AT KIWD/KCMX/KSAW AHEAD OF
AN APPROACHING COLD FRONT. COLD FRONT WILL MOVE ACROSS THE AREA
DURING THE AFTN/EVENING...RESULTING IN WINDS BECOMING N TO NE. AT
THE SAME TIME...WIDESPREAD RAIN NOW ORGANIZING AND LIFTING NNE THRU
THE MID MISSISSIPPI VALLEY WILL OVERSPREAD THE AREA TONIGHT. UPSLOPE
WIND AND RAIN WILL RESULT IN IFR CONDITIONS AT KCMX AND LIFR AT
KIWD/KSAW AS WIND DIRECTION WILL BE A MORE IDEAL UPSLOPE DIRECTION
AT THOSE TERMINALS. EXPECT HEAVIEST RAINFALL AND MORE RESTRICTED VIS
AT KSAW. RAIN WILL END W TO E TUE MORNING/EARLY AFTN. INFLUX OF
DRIER AIR WILL ALLOW KIWD/KCMX TO IMPROVE TO MVFR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 357 AM EDT MON OCT 13 2014
A WEAKENING PRESSURE GRADIENT ACROSS THE AREA WILL LEAD TO WINDS
WILL DROPPING BELOW 10KT ACROSS THE LAKE BY THIS AFTERNOON. AS A LOW
PRESSURE SYSTEM SLOWLY LIFTS NE...WINDS WILL BECOME N TO NE TONIGHT
AND WILL INCREASE LATE. TUE AND TUE NIGHT...EXPECT N TO NE WINDS UP
TO 20KT ON WRN LAKE SUPERIOR AND UP TO 25KT ON ERN LAKE SUPERIOR.
THE LOW WILL THEN WEAKEN AS IT DRIFTS NE ACROSS THE GREAT LAKES
REGION WED/THU...ALLOWING WINDS TO DIMINISH. WINDS SHOULD BE UNDER
10KT BY THU. ANOTHER LOW PRESSURE SYSTEM TRACKING ACROSS SRN CANADA
THU WILL THEN MERGE WITH THE REMNANT GREAT LAKES LOW ON FRI IN THE
VICINITY OF JAMES BAY. THIS WILL RESULT IN INCREASING W TO NW INTO
THE 15-25KT RANGE ON FRI.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...TITUS
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
102 PM CDT Mon Oct 13 2014
.UPDATE:
Issued at 1250 PM CDT Mon Oct 13 2014
Expanded tornado watch to include Greene, Jersey, Macoupin and
Montgomery in Illinois. Updated grids/zones accordingly. Minor
adjustments made to pops and temps.
Byrd
&&
.SHORT TERM: (Through Late This Afternoon)
Issued at 355 AM CDT Mon Oct 13 2014
Warm front extending from near Joplin to Jefferson City and through
the St. Louis Metro area northeast to near Decatur will continue to
lift slowly north today as a strong trof and associated wound up
surface low moves northeast through Missouri. Strong low level warm
advection ahead of the system will produce scattered to numerous
showers and thunderstorms this morning. All short-range guidance is
very consistent in developing a wave of convection this morning
with a break before another round this afternoon. With some dry
time and a bit of insolation, MUCAPE in excess of 1000 J/Kg should
result. Very strong wind fields and plenty of shear will likely
produce severe thunderstorms this afternoon...primarily along and
east-southeast of the I-44 corridor. 4km NSSL and NCEP WRF models
along with the HRRR develop a strong squall line which moves rapidly
east this afternoon. SPC day 1 outlook has about the southeast 1/2
to 2/3 of the area in a slight risk with the moderate clipping
Reynolds, Iron and Madison counties. Primary concern will be
damaging winds given the very strong wind fields, and there could be
a few tornadoes as 0-1km helicity is forecast to be in excess of 200
m2/s2. Lack of steep lapserates aloft precludes a high hail risk.
Carney
.LONG TERM: (Tonight through Sunday)
Issued at 355 AM CDT Mon Oct 13 2014
A strong storm system is still set to deepen and slowly move through
our region over the next few days. It will initially close off this
evening over far southwestern MO and then not begin to pull away
from our region to the east until Wednesday, but its influences will
still be felt thru Wednesday night and perhaps into Thursday.
The main severe thunderstorm threat from this system will be on its
front-end, and is expected to be ongoing early this evening from the
lower MS Valley into southern IL. The convective mode by this time
is expected to be a squall line with damaging winds and isolated
imbedded tornadoes. All indications, though, is that the severe
thunderstorm threat should end by 9pm across our region as it pushes
east.
Heading into late tonight and through Wednesday, the primary focus
at this point will be the deformation zone pcpn, which will be best
focused down our way using the expected location of the TROWAL and
decently strong lo-level convergence. With a system this wrapped up
expected, went above MAV MOS PoPs, tapering back to MOS by Wednesday
night. Added in some small mentionable PoPs for Thursday in parts
of southern IL with the trends all heading in that direction, with
stronger indications of more persistent, deep cyclonic flow.
MOS temps thru Wednesday look reasonable, but adjusted daytime maxes
a bit lower where we expect the most peristent, and high, rain
chances to be.
Northwest upper flow is still on track for late week and next
weekend, with a couple of glancing blows from upper level
disturbances on Friday and Sunday, but moisture looks severely
limited enough to hold off on chance mention for now. Temps should
be near seasonal normals.
TES
&&
.AVIATION: (For the 18z TAFs through 18z Tuesday Afternoon)
Issued at 102 PM CDT Mon Oct 13 2014
Surface low now near KSZL and continues to track to the north
northeast today. So taf sites to remain on warm side with
southeast to south winds. With dry slot moving in, should see cigs
lift a bit waffling between mvfr and vfr through the afternoon and
early evening hours. Then as main cold front begins to move east
will see ifr cigs return to KUIN and KCOU tonight with some light
rain. As for metro area tafs, could see additional storms fire up
this afternoon, but hard to pin down timing and location, so
just have showers with vcnty thunder possible through 23z and
gusty southeast to south winds. Then winds to diminish towards sunset.
Winds to veer to northwest to north at KCOU by 10z Tuesday and by
11z Tuesday at KUIN. As for metro area it will be just after 18z
Tuesday when front moves through.
Specifics for KSTL:
Surface low now near KSZL and continues to track to the north
northeast today. So taf sites to remain on warm side with
southeast to south winds. With dry slot moving in, should see cigs
lift a bit waffling between mvfr and vfr through the afternoon and
early evening hours. For metro area, could see additional storms
fire up this afternoon, but hard to pin down timing and location,
so just have showers with vcnty thunder possible through 23z and
gusty southeast to south winds. Then winds to diminish towards
sunset. Later tonight will see ifr/mvfr cigs moving in, timing and
coverage hard to pin down. Better chances of ifr cigs with cold
frontal passage around 19z Tuesday as winds veer to the west and
some light rain moves in.
Byrd
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1259 PM CDT MON OCT 13 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 316 AM CDT MON OCT 13 2014
MAIN FORECAST CONCERNS WILL BE ENDING PRECIPITATION THIS MORNING AND
WINDS FOR TODAY.
LATEST RADAR TRENDS SHOW SHOWERS IN THE WESTERN PART OF THE FORECAST
AREA THAT ARE MOVING SOUTH AND ANOTHER AREA OF SHOWERS TO THE
SOUTHEAST THAT IS MOVING TO THE NORTH. SURFACE ANALYSIS HAS A COLD
FRONT JUST ABOUT TO EXIT THE FAR SOUTHEAST PART OF THE FORECAST AREA
ALREADY THIS MORNING.
SHORT TERM MODELS HAVE A VARIETY OF SOLUTIONS FOR THE CURRENT
PRECIPITATION. THE HRRR AND RAP TRY TO BRING THE SHOWERS TO THE
SOUTHEAST NORTH INTO THE FORECAST AREA...BUT THE TREND ON THESE HAVE
BEEN TO WEAKEN A LITTLE AS THEY MOVE TO THE NORTH. ON THE OTHER HAND
THE 4KM WRF KEEPS IT MOSTLY TO THE SOUTHEAST OF THE AREA. THE
PRECIPITATION TO THE WEST IS NOT HANDLED WELL WITH THE MODELS. WITH
THAT IN MIND...HAVE KEPT POPS IN THE SOUTHERN/SOUTHEASTERN PART OF
THE FORECAST AREA THROUGH THE MORNING HOURS...BUT LOWERED THE
CHANCES. HAVE KEPT THUNDER OUT SINCE THE MUCAPE IS NON-EXISTENT AND
THERE HAS ONLY BEEN A RARE LIGHTNING STRIKE IN THE PAST COUPLE OF
HOURS.
NORTH OR NORTHWEST WINDS HAVE ALREADY STARTED INCREASING THIS
MORNING. MOST LOCATIONS HAVE WINDS AT 15 TO 20 MPH WITH GUSTS TO
AROUND 25 MPH ALREADY. EXPECT THE TREND TO INCREASE AND AS THE SUN
RISES THIS MORNING AND THE INVERSION BREAKS STRONGER WINDS WILL MIX
DOWN. WINDS AT 850MB ARE STRONGEST AT 12Z THIS MORNING...BUT REMAIN
AROUND 40 KNOTS THROUGH THE AFTERNOON. WILL KEEP THE WIND ADVISORY
THROUGH THE DAY.
AS THE SUN SETS THIS EVENING...WINDS WILL DROP OFF BUT STILL REMAIN
BREEZY FOR A COUPLE OF HOURS. LATER TONIGHT A SURFACE HIGH PRESSURE
SYSTEM WILL START TO BUILD INTO THE AREA AND WINDS WILL DIMINISH.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 316 AM CDT MON OCT 13 2014
GUIDANCE SUGGESTS THE LONG TERM FORECAST PERIOD WILL START WITH AN
UPPER TROPOSPHERIC TROUGH OVER CENTRAL AND EASTERN PORTIONS OF THE
CONUS...AND A RIDGE OVER THE WEST. THE RIDGE OVER THE WEST IS
EXPECTED TO MOVE EAST INTO THE CENTRAL CONUS ON WEDNESDAY...BEFORE
WEAKENING THUS ALLOWING FOR QUASI-ZONAL UPPER TROPOSPHERIC FLOW OVER
OUR AREA ON THURSDAY. A STRENGTHENING UPPER TROPOSPHERIC TROUGH OVER
THE GREAT LAKES REGION IS THEN EXPECTED TO TURN OUR FLOW MORE
NORTHWESTERLY FRIDAY THROUGH SUNDAY.
AN OVERALL LACK IN OMEGA SHOULD PROMOTE DRY CONDITIONS TO OUR AREA AS
THE AFOREMENTIONED UPPER TROPOSPHERIC RIDGE AXIS MOVES OVER THE
REGION. SUCH HAS BEEN PRESENTED IN THE OFFICIAL FORECAST. ONE COULD
ARGUE THAT THE PASSAGE OF A WEAK UPPER TROPOSPHERIC PERTURBATION...OR
PERHAPS ENHANCED JET DYNAMICS...COULD BRING CHANCES FOR LIGHT
PRECIPITATION TO THE REGION THURSDAY ONWARD...BUT AT THIS TIME
TROPOSPHERIC MOISTURE APPEARS AS THOUGH IT WILL BE EXTREMELY LACKING
THURSDAY THROUGH SUNDAY AND AS A RESULT...ALSO WENT AHEAD WITH DRY
CONDITIONS THROUGH THE WEEKEND.
SOUTHERLY BOUNDARY-LAYER RETURN FLOW IS EXPECTED TO OVERTAKE THE
REGION STARTING ON WEDNESDAY AND AS A RESULT...THERMAL ADVECTION
THROUGH THE BOUNDARY LAYER SHOULD PROMOTE A GENERAL WARMING TREND
FROM DAY TO DAY BETWEEN TUESDAY AND THURSDAY...WITH HIGHS CLIMBING
FROM THE 60S ON TUESDAY TO THE LOW TO MID 70S BY THURSDAY. THE
PASSAGE OF A WEAK BOUNDARY-LAYER BAROCLINIC ZONE IS THEN EXPECTED TO
BRING A SLIGHT COOL DOWN TO FINISH THE FORECAST PERIOD...WITH HIGHS
BACK IN THE 60S FRIDAY THROUGH SUNDAY. TUESDAY NIGHT
/ WEDNESDAY MORNING LOWS IN THE MID TO UPPER 30S WILL ALSO BE SHORT
LIVED AS BOUNDARY-LAYER THERMAL ADVECTION OVERTAKES THE AREA...WITH
LOWS GENERALLY IN THE 40S THEN EXPECTED THROUGH THE REMAINDER OF THE
FORECAST PERIOD.
&&
.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1253 PM CDT MON OCT 13 2014
VFR CONDITIONS WILL PREVAIL AT BOTH TERMINALS THROUGH THE PERIOD
WITH VERY STRONG NORTHWESTERLY WINDS EXPECTED TO PERSIST THROUGH
THE LATE AFTERNOON HOURS TODAY. EXPECT THE RESPONSIBLE STRONG LOW
PRESSURE SYSTEM ACROSS THE LOWER MISSOURI RIVER VALLEY TO SHIFT
EAST NORTHEAST AND FURTHER AWAY FROM THE LOCAL AREA THIS
EVENING...WITH A RELAXING PRESSURE GRADIENT EXPECTED ACROSS THE
LOCAL AREA OVERNIGHT AS THE WINDS AT THE SURFACE DECOUPLE SOMEWHAT
FROM THE STRONGER WINDS ALOFT. AS A RESULT...COULD SEE SOME
MARGINAL LOW LEVEL WIND SHEAR OVERNIGHT...BUT WITH SURFACE WINDS
IN THE 12-15KT RANGE...THINK WIND SHEAR WILL BE BELOW THE 30KT
CRITERIA. LIGHTER NORTHWESTERLY WINDS AND CLEAR SKIES ARE
EXPECTED DURING THE DAY TUESDAY.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NEZ039>041-046>049-
060>064-072>077-082>087.
KS...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR KSZ005>007-017>019.
&&
$$
SHORT TERM...JCB
LONG TERM...BRYANT
AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
1124 AM MDT MON OCT 13 2014
.AVIATION...
18Z TAF CYCLE
SKIES WILL CONTINUE TO CLEAR INTO THE AFTERNOON WITH VFR
CONDITIONS PREVAILING ACROSS NORTHERN AND CENTRAL NEW MEXICO
THROUGH THE NEXT 24 HOURS. SOME STIFF NORTHERLY GUSTS WILL
CONTINUE TO IMPACT FAR EASTERN NEW MEXICO THROUGH THE MID
AFTERNOON...INCLUDING KCAO...KTCC...AND KCVS WHERE A FEW GUSTS OF
30 TO 35 KT WILL BE POSSIBLE BEFORE 13/2100UTC.
52
&&
.PREV DISCUSSION...603 AM MDT MON OCT 13 2014...
.UPDATE...
EXPIRED WIND ADVISORY ACROSS NORTHEASTERN NEW MEXICO. WINDS HAVE
TAPERED OFF TO BETWEEN 15 AND 25MPH WITH GUSTS UP TO 35 MPH FROM
CLAYTON TO CLOVIS. THE 09Z HRRR 10-METER WIND SHOWS WINDS WILL
INCREASE SLIGHTLY AGAIN FOR AN HOUR OR TWO LATE THIS MORNING BEFORE
TAPERING OFF AGAIN THIS AFTERNOON. WILL NOT EXTEND THE HIGHLIGHT
FOR THIS BRIEF WINDIER PERIOD AS THE MAIN IMPACT WINDOW HAS ENDED
AND THESE WINDS ARE NOT EXPECTED TO BE NEARLY AS STRONG AS WHAT
WAS EXPERIENCED OVERNIGHT AND LAST EVENING.
GUYER
&&
.PREV DISCUSSION...556 AM MDT MON OCT 13 2014...
.AVIATION...
12Z TAF CYCLE
STILL SOME BREEZY TO WINDY CONDITIONS ACROSS MAINLY THE EASTERN
BORDER COUNTIES OF NM INTO MIDDAY OR EARLY AFTN THEN DIMINISHING
SOME THROUGH THE MID AND LATE AFTN. SOME GUSTS MAY STILL REACH
BETWEEN 25 AND 35KT OUT EAST WITH TCC A LIKELY IMPACTED TAF SITE.
A FEW FOG POCKETS POSSIBLE THROUGH MID MORN ACROSS SOME OF THE
COLDER AND WETTER MOUNTAIN VALLEYS IN NORTHERN NM. OTHERWISE VFR
CONDITIONS BY FAR THE RULE AS DRY AND DIMINISHING N TO NW FLOW
ALOFT WILL BE IN PLAY THROUGH THE END OF THE FCST PERIOD.
43
&&
.PREV DISCUSSION...344 AM MDT MON OCT 13 2014...
.SYNOPSIS...
THE STORM SYSTEM THAT BROUGHT ALL THE STRONG WINDS TO THE REGION
SUNDAY WILL GRADUALLY EXIT THE AREA TODAY. CONDITIONS WILL REMAIN
WINDY OVER THE EASTERN PLAINS ALONG THE TEXAS STATE LINE THROUGH
LATE THIS MORNING. OTHERWISE...TEMPERATURES WILL BE A LITTLE BELOW
NORMAL FOR MID OCTOBER WITH LOTS OF SUNSHINE. CHILLY TEMPERATURES
WILL DEVELOP AGAIN TONIGHT WITH CLEAR SKIES AND LIGHT WINDS. VERY
PLEASANT WEATHER IS ON TAP TUESDAY THROUGH THURSDAY WITH WARMER
TEMPERATURES AND SUNNY SKIES.
&&
.DISCUSSION...
MAIN CONSIDERATIONS THIS MORNING WERE STRENGTH AND DURATION OF WINDY
CONDITIONS ACROSS THE FAR EASTERN PLAINS...AND FREEZING TEMPERATURES
OVER PORTIONS OF NORTHERN NM TONIGHT. LATEST OBSERVATIONS SHOW SURFACE
WINDS ARE STILL ELEVATED FROM CLAYTON TO TUCUMCARI AND CLOVIS...BUT
SPEEDS ARE ONLY MARGINAL TO SLIGHTLY UNDER ADVISORY CRITERIA. WINDS
MAY COME BACK UP WITH INITIAL MIXING THIS MORNING FOR A FEW HOURS SO
THE POTENTIAL IS THERE FOR AN HOUR OR TWO OF ADVISORY WINDS AGAIN.
WILL NOT HOWEVER EXTEND PRODUCT SINCE MAIN IMPACT PERIOD IS OVER AND
WINDS WILL NOT BE NEAR AS STRONG AS WHAT HAS ALREADY OCCURRED. THE
SURFACE PRESSURE GRADIENT IS PROGGED TO WEAKEN SIGNIFICANTLY THROUGH
THE MORNING SO CONFIDENCE ON EXTENSION OF THE ADVISORY IS LOW. TEMPS
ARE ALSO STRUGGLING TO FALL OVER THE NW PLATEAU WHERE WINDS REMAINED
ELEVATED THROUGH 3 AM...SO WILL CANCEL THAT PORTION OF THE FREEZE
WARNING. THE AREA AROUND ESPANOLA IS ALSO NOT FALLING AS MUCH AS
DESIRED FOR FREEZING CONDITIONS...BUT POINTS IMMEDIATELY TO THE
NORTH AND WEST MAY HIT FOR AN HOUR OR TWO.
THE NEXT CHALLENGE WAS TONIGHTS TEMPS. THE BULK OF MOS GUIDANCE HAS
READINGS ONLY HOVERING NEAR FREEZING ACROSS FREEZE ZONES IN THE
NORTH...EXCEPT THE MET...WHICH IS MUCH COLDER. WENT WITH CONSENSUS
GUIDANCE AND WILL ALLOW DAY SHIFT TO TAKE ANOTHER LOOK BEFORE A
FREEZE WARNING IS ISSUED. OTHERWISE...TEMPS WILL ACTUALLY BE CLOSE
TO NORMAL TONIGHT FOR MOST AREAS UNDER CLEAR SKIES AND LIGHT WINDS.
THE PICK OF THE WEEK IS TUESDAY AS HIGH PRESSURE BEGINS BUILDING
WEST OF NM. THIS WILL ALLOW FOR LIGHT WINDS...BRIGHT SUNNY SKIES...
AND WARMING TEMPS. TUESDAY NIGHT WILL BE CHILLY AGAIN BUT WARMER
THAN TONIGHT. THE H5 HIGH CENTER WILL CREST OVER SE ARIZONA AT 589DM
WEDNESDAY MORNING THEN BREAK DOWN OVER NM THROUGH WEDNESDAY NIGHT.
YET ANOTHER DELIGHTFUL DAY IS ON TAP WITH EVEN WARMER TEMPS...SUNNY
SKIES...AND DRY CONDITIONS. SURFACE LEE TROUGHING WILL INCREASE OVER
THE EAST AND SUBSEQUENTLY WILL THE TEMPS WITH KATABATIC FLOW. HIGHS
WILL AVERAGE BTWN 5 AND 15F ABOVE NORMAL. ZONAL FLOW IS EXPECTED TO
INCREASE THURSDAY BEHIND THE FLATTENING RIDGE. A WEAK BACK DOOR FRONT
ENTERING THE PLAINS WILL TREND TEMPS BACK TOWARD NORMAL.
GUYER
&&
.FIRE WEATHER...
BRISK NORTHERLY WINDS ACROSS A GOOD PORTION OF THE EASTERN PLAINS
WILL EASE BACK JUST A BIT THROUGH THE EARLY MORN HOURS IN EAST
QUARTER TO THIRD OF NM...BUT SHOULD...FOR A 2 TO 4 HOUR PERIOD MID
MORN TO AROUND MIDDAY TODAY...INCREASE BACK TO NEAR THE 20 TO NEARLY
35 MPH RANGE. DURING THIS CRITICAL WIND SPEED PERIOD...RH VALUES NOT
EXPECTED TO DROP TO CRITICAL VALUES. THIS PLUS THE RECENT DECENT
RAINS ACROSS A GOOD PORTION OF THIS AREA WOULD PRECLUDE ANY RED FLAG
CONDITIONS. IN FACT AFTER THE MIDDAY OR EARLY AFTN PERIOD...IT LOOKS
LIKE CRITICAL FIRE WX CONDITIONS ARE NOT LIKELY THROUGH THE WHOLE
WEEK AS WINDS WILL DECREASE SIGNIFICANTLY LATER TODAY AND STAY BELOW
CRITICAL VALUES FOR SOME TIME. TEMPERATURES TO BE COOLER THAN THE
NORM TODAY...BUT BY TUE AFTN LOOKING AT VALUES JUST A FEW DEGREES
EITHER SIDE OF SEASONAL NORMS. THEREAFTER ABOVE NORMAL VALUES INTO
THIS NEXT WEEKEND. VENTILATION RATES GENERALLY VERY GOOD TO
EXCELLENT EAST THIRD...MOSTLY GOOD NORTH AND POOR TO FAIR GENERALLY
ELSEWHERE. EXPECT BETTER RADIATIONAL COOLING AND STRONGER TEMP
INVERSIONS TONIGHT INTO EARLY TUESDAY MORNING. COLDER TEMPERATURES
CAN BE EXPECTED WITH MORE READINGS AT OR BELOW FREEZING...INCLUDING
THE POTENTIAL FOR A FREEZE IN SOME OF THE NORTHEAST HIGHLANDS...
ESTANCIA VALLEY...AND OTHER SHELTERED LOCATIONS.
A PROGRESSIVE UPPER RIDGE WILL EASE INTO NM TUE. DESPITE THE
AFOREMENTIONED WARM-UP...LOOK FOR POOR VENTILATION RATES EXCEPT
PERHAPS IN THE FAR EAST. DRY AND CLEAR CONDITIONS OTHERWISE AREAWIDE
TUE.
THE REMAINDER OF THE WORK WEEK APPEARS TO REMAIN DRY AND TRANQUIL.
A WIND SHIFT IN THE EAST COULD LOWER TEMPERATURES A FEW TO SEVERAL
DEGREES IN THE EAST FRIDAY...BUT CONDITIONS WILL STILL BE FAIRLY
TRANQUIL. LOOKING AT SOME MINOR TO MODERATE IMPROVEMENT IN
VENTILATION RATES WED THROUGH FRI...BUT GENERALLY NO BETTER THAN
FAIR TO GOOD.
43
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORMAN OK
301 PM CDT MON OCT 13 2014
.DISCUSSION...
PRIMARY FORECAST CONCERN REMAINS FOCUSED ON RAIN ENDING AND STRONG
NORTHWEST WINDS.
CURRENTLY... LIGHT TO MODERATE RAINFALL CONTINUES TO SLOWLY SHIFT
EASTWARD OUT OF CENTRAL OK. EXPECT PRECIP TO CONTINUE THROUGH THE
EARLY EVENING... SLOWLY TAPERING OFF ACROSS THE OKC METRO THROUGH 4-
5 PM CDT. RECENT RUNS OF THE HRRR APPEAR TO HAVE A DECENT HANDLE ON
THE PRECIP TRENDS... SO LEFT A SLIGHT CHANCE THROUGH THE LATE
EVENING... 7-10PM FOR LOCATIONS ALONG I-35 IN N CENTRAL OK. STRONG
NW WINDS WILL CONTINUE TO PERSIST ACROSS WRN AND CENTRAL OK THROUGH
THE EVENING. THROUGH 300 PM CDT... SITES ACROSS WRN OK CONTINUE
TO REPORT GUSTS OF 35 TO 45 MPH... WHERE CLEARING CONTINUES...
THUS RESULTING IN BETTER BL MIXING. WINDS WILL REMAIN BREEZY
THROUGH THE EVENING... RELAXING GRADUALLY AFTER SUNSET. NW WINDS
WILL CONTINUE THROUGH TUE... PICKING UP THROUGH THE LATE
MORNING/AFTN WITH INCREASED MIXING DUE TO DAY TIME HEATING. NOT AS
WINDY AS TODAY... GUSTS TMRW WILL APPROACH 20 TO 30 MPH ACROSS
PORTIONS OF CENTRAL AND ERN OK. WITH NW WINDS CONTINUING THROUGH
TUE... TEMPS WILL ONLY TOP OUT IN THE UPPER 60S/LOWER 70S ACROSS
OK... AND MID 70S IN WRN N TX.
FOR THE REMAINDER OF THE WEEK... INTO THE WEEKEND... RIDGING WILL
DEVELOP WED ACROSS THE CENTRAL CONUS. IN RESPONSE... SOUTH WINDS
WILL RETURN... RESULTING IN A GRADUAL WARM UP THROUGH SUN. NOT
RECORD WARMTH... BUT HIGHS WILL BE A 5-7 DEGREES ABOVE AVG... IN THE
UPPER 70S TO LOWER 80S AT TIMES FROM WED-SUN.
LATE THIS WEEKEND... LONG RANGE GUIDANCE IS SHOWING HINTS OF ANOTHER
H500 SHORTWAVE... SO PRECIP CHANCES MAY RETURN LATE SUN-MON.
JTK
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 46 70 45 76 / 10 0 0 0
HOBART OK 45 73 45 78 / 0 0 0 0
WICHITA FALLS TX 47 75 47 80 / 0 0 0 0
GAGE OK 41 72 41 78 / 0 0 0 0
PONCA CITY OK 47 70 42 72 / 20 0 0 0
DURANT OK 49 73 48 76 / 10 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR OKZ004>031-033>041-
044>046-050.
TX...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR TXZ083>090.
&&
$$
11/04
AREA FORECAST DISCUSSION
NWS PORTLAND OR
915 AM PDT MON OCT 13 2014
.SYNOPSIS...A FLAT UPPER RIDGE WILL BE OVER SOUTHWEST WASHINGTON AND
NORTHWEST OREGON EARLY TODAY. A FAIRLY STRONG AND WET COLD FRONT WILL
THEN START TO SPREAD ONTO THE COAST AND INTO THE COAST RANGE THIS
AFTERNOON AND OVER THE REMAINDER OF THE INLAND AREAS LATE TODAY AND
ESPECIALLY TONIGHT...STALLING OVER SOUTHWEST WASHINGTON AND NORTHWEST
OREGON TUESDAY. A SHORTWAVE WILL SWING AROUND THE COOL PARENT
OFFSHORE UPPER TROUGH AND HELPS MOVE THE FRONT AND UPPER TROUGH
THROUGH OUR FORECAST AREA TUESDAY NIGHT AND WEDNESDAY FOR ANOTHER
ROUND OF RAIN OR SHOWERS. AFTER SOME LIGHT PRECIPITATION LINGERS ON
THURSDAY...ANOTHER FAIRLY STRONG FRONTAL SYSTEM IS EXPECTED TO AFFECT
THE PACIFIC NORTHWEST DURING THE LATTER PART OF THE WEEK INTO THE
UPCOMING WEEKEND.
&&
.UPDATE... EASTERN EDGE OF A COLD FRONT LOCATED JUST WEST OF THE
LOCAL MARINE AREA WITH RAIN STILL ABOUT 150 NM OFFSHORE BASED ON THE
LANGLEY HILL RADAR. HOWEVER THERE MAY BE SOME LIGHTER RAIN CLOSER TO
THE OREGON COAST. HRRR SHOWS RAIN ARRIVING AT THE N OR/S WA COAST IN
THE EARLY AFTERNOON WHICH SEEMS REASONABLE. DELAYED HIGH POPS
SLIGHTLY FROM THE GORGE SOUTH ACROSS THE CASCADES AND FOOTHILLS DUE
TO SLOWER TRACKING OF THE SYSTEM. DON`T EXPECT IT TO SPEED UP WITH
UPPER FLOW NEARLY PARALLEL TO THE FRONT. ALSO MADE SOME CHANGES TO
SKY COVER TO REFLECT THE PERCEPTION OF A RATHER SUNNY DAY DESPITE THE
SKY TECHNICALLY BEING MOSTLY COVERED WITH THIN HIGH CLOUDS. BOWEN
.SHORT TERM (PREVIOUS DISCUSSION)...NATIONAL WEATHER SERVICE DOPPLER
RADAR IS RATHER QUIET EARLY THIS MORNING AS WEAK UPPER LEVEL RIDGING
HAS DECREASED ANY LEFTOVER SHOWER ACTIVITY. THE RIDGE IS A BIT DIRTY
WITH SOME HIGHER CLOUDS MOVING ACROSS MAINLY AREAS NORTH OF ABOUT THE
COLUMBIA RIVER. OTHERWISE SKIES ARE ON THE CLEAR SIDE. HOWEVER...WITH
FAIRLY NARROW TEMPERATURE DEWPOINT SPREADS...EXPECT AREAS OF MORNING
LOW ELEVATIONS FOG TO DEVELOP.
ATTENTION THEN TURNS TO THE RATHER IMPRESSIVE MOIST FRONT APPROACHING
130W EARLY THIS MORNING. THE MODELS ARE IN PRETTY GOOD AGREEMENT
BRINGING SOME RAIN INTO THE COAST AND COAST RANGE THIS
AFTERNOON...AND INTO THE THE REMAINDER OF THE INLAND AREAS LATE TODAY
BUT MAINLY THIS EVENING AND TONIGHT. THE FRONT BECOMES PARALLEL TO
THE UPPER LEVEL FLOW...SO THIS SLOWS ITS MOVEMENT THROUGH OUR
FORECAST AREA TONIGHT AND TUESDAY...WITH THE FRONT STALLING OVER THE
AREA TUESDAY. PRECIPITABLE WATER VALUES ARE UP AROUND 1.25
INCHES...SO THIS SHOULD BRING A FINAL END TO THE FIRE WEATHER SEASON.
THE MODELS DO INDICATE THE PRECIPITATION IN THE FRONTAL BAND MAY LET
UP SOME TUESDAY AFTERNOON.
HOWEVER...AFTER THAT...THERE IS A SHORT WAVE THAT SWINGS AROUND THE
BASE OF THE OFFSHORE ASSOCIATED COOL UPPER TROUGH AND THEN MOVES
NORTHEAST THROUGH OUR FORECAST AREA TUESDAY NIGHT AND WEDNESDAY. THIS
SHOULD BRING ANOTHER SURGE OF RAIN OR SHOWERS AS IT MOVES THROUGH.
THE MODELS SHOW SOME INSTABILITY AS THIS FEATURE MOVES THROUGH...SO
WE HAVE SLIGHT CHANCE OF THUNDERSTORMS IN THE COASTAL WATERS AND
ALONG THE COAST LATE TUESDAY AND TUESDAY NIGHT SPREADING INLAND
WEDNESDAY MORNING. SNOW LEVELS WILL ALSO BE LOWERING DOWN TO NEAR
5000 FEET TUESDAY NIGHT AND WEDNESDAY...AND WE SHOULD SEE SOME
ACCUMULATING SNOW UP IN THE CASCADES. TOLLESON
.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY...AS THE MAIN SHORT WAVE
SWINGS INLAND ON WEDNESDAY...THE ASSOCIATED UPPER TROUGH AXIS MOVES
INLAND AS WELL WITH DECREASING SHOWERS WEDNESDAY NIGHT AND THURSDAY.
THE NEXT STRONGER LOW PRESSURE SYSTEM IS THEN EXPECTED TO BRING MORE
RAIN AND COASTAL BREEZES TO OUR AREA FRIDAY AND ESPECIALLY FRIDAY
NIGHT INTO SATURDAY. THERE MAY BE A BREAK IN THE WEATHER AGAIN SUNDAY
BEFORE THE NEXT FRONT EARLY NEXT WEEK. TOLLESON
&&
.AVIATION...HIGH PRES WITH DRY VFR CONDITIONS PREVAILING ACROSS
MUCH OF THE AREA THIS MORNING WITH VARIABLE MID AND HIGH CLOUDS.
THE MAIN EXCEPTION THIS MORNING IS THE SOUTHERN HALF OF THE
WILLAMETTE VALLEY WHERE OVERNIGHT CLEAR SKIES HAVE ENABLED
RADIATIONAL FOG TO FORM. OBSERVATIONS AND CAMERAS SUGGEST A
RELATIVELY THIN LAYER OF FOG/LOW CLOUDS THAT WILL LIKELY
DISSIPATE BY 17Z. MEANWHILE...AN APPROACHING COLD FRONT WILL REACH
THE COAST BY THIS AFTERNOON AND PUSH INLAND TO THE INTERIOR TAF
SITES IN THE EVENING. EXPECT A REDUCTION TO MVFR AND RAIN
BEGINNING ALONG THE COAST LATER THIS MORNING...WITH IFR CIGS
POSSIBLE AS FRONT ADVANCES. GUSTY S WINDS CAN BE EXPECTED ALONG
THE COAST AHEAD OF THE FRONT. FOR THE INLAND AREAS...VFR AFTER
ANY FOG THAT DEVELOP CLEARS THIS MORNING. INCREASING CLOUDS WITH
RAIN DEVELOPING IN THE AFTERNOON. MVFR CONDITIONS LIKELY AS THE
FRONT MOVES THROUGH LATER IN THE EVENING.
KPDX AND APPROACHES...VFR WITH PATCHY IFR FOG IN THE AREA THIS
MORNING. RAIN ACCOMPANYING A FRONT WILL LIKELY ARRIVE AFTER 00Z
TUESDAY WITH INCREASING CHANCES FOR MVFR CONDITIONS DEVELOPING
AFTER 06Z TUESDAY. CULLEN
&&
.MARINE...SOUTH WINDS WILL INCREASE ACROSS THE WATERS TODAY AHEAD
OF AN ADVANCING COLD FRONT. SMALL CRAFT ADVISORY LEVEL WINDS
DEVELOP LATER THIS MORNING THROUGH EARLY EVENING. HOWEVER...THE
FRONT IS EXPECTED TO BRING GALE GUSTS ACROSS THE WATERS NORTH OF
CASCADE HEAD DURING THE SAME TIME PERIOD AND A WEAK JET MAY
ENHANCE WINDS A LITTLE MORE WITHIN 20 NM OF THE COAST FROM THE
COLUMBIA RIVER MOUTH AND POINTS NORTHWARD.
ANOTHER WEAK FRONT AND ASSOCIATED LOW PRES SYSTEM WILL MOVE INTO
THE REGION ON WEDNESDAY. STILL SOME DIFFERENCES BETWEEN FORECAST
MODELS IN TERMS OF STRENGTH AND LOCATION OF THIS...BUT THEY GENERALLY
SUPPORT ADVISORY STRENGTH WINDS. HOWEVER GIVEN THE OVERALL
SYNOPTIC PATTERN...WOULD NOT BE SURPRISED IF THE LOW PRES CENTER
TRACKS A LITTLE CLOSER TO THE WATERS AND PRODUCES SOME LOW END
GALE GUSTS OVER THE WATERS. WILL CONTINUE TO MONITOR.
A STRONGER LOW PRES SYSTEM WILL DEVELOP LATE THU OR FRI AND MOVE N
TOWARDS SOUTHERN B.C. AND WOULD RESULT IN A STRONG FRONTAL SYSTEM
MOVING THROUGH THE COASTAL WATERS. THIS WOULD RESULT IN A STRONG
FRONT MOVING ACROSS THE WATERS DURING THE PERIOD...WITH THE
CAPABILITY TO PRODUCE GALES ACROSS ALL WATERS...AND COASTAL JET
DEVELOPMENT COULD CERTAINLY ENHANCE WINDS WITHIN 20 NM OF THE
COAST. HOWEVER...CONFIDENCE IN SPECIFIC DETAILS OF THE SYSTEM
REMAINS LOW AND WILL CONTINUE TO EVALUATE MODEL GUIDANCE IN THE
COMING DAYS AS THE TRACK AND EVOLUTION OF THE LOW PRES WILL
GREATLY INFLUENCE POTENTIAL IMPACTS.
OTHERWISE...COMBINED SEAS WILL ALTERNATE BETWEEN AROUND 9-10 FT
IN BETWEEN FRONTAL SYSTEMS AND BUILDING INTO THE 11 TO 15 FT RANGE
AS SWELLS ARRIVE. HOWEVER...ANY EXTENDED PERIODS OF GALES WILL BE
MORE LIKELY TO PUSH SEAS CLOSER TO 20 FT...THOUGH CONFIDENCE
REMAINS LOWER AS THE DETAILS OF THE WED AND FRI LOW PRES SYSTEMS
ARE YET TO BE DETERMINED. CULLEN
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...GALE WARNING FROM NOON TODAY TO 6 PM PDT THIS EVENING FOR
WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR FROM
10 TO 60 NM.
GALE WARNING FROM 2 PM THIS AFTERNOON TO 9 PM PDT THIS EVENING
FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD
OR OUT 10 NM.
SMALL CRAFT ADVISORY FOR WINDS FROM 11 AM THIS MORNING TO 8 PM
PDT THIS EVENING FOR WATERS FROM CASCADE HEAD TO FLORENCE
OR FROM 10 TO 60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 AM PDT TUESDAY
FOR COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT
60 NM.
SMALL CRAFT ADVISORY FOR WINDS FROM 2 PM THIS AFTERNOON TO
11 PM PDT THIS EVENING FOR COASTAL WATERS FROM CASCADE HEAD TO
FLORENCE OR OUT 10 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 11 PM
PDT THIS EVENING.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
&&
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
158 PM EDT MON OCT 13 2014
.SYNOPSIS...
COOL HIGH PRESSURE ACROSS THE MID-ATLANTIC WILL GRADUALLY RELAX
ITS INFLUENCE ON OUR WEATHER TODAY AS SOUTHERLY FLOW INCREASES IN
ADVANCE OF A DEEPENING TROUGH OF LOW PRESSURE ACROSS THE CENTRAL
UNITED STATES. THIS TROUGH AND A STRONG SURFACE COLD FRONT WILL
MOVE ACROSS THE AREA TUESDAY NIGHT AND WEDNESDAY WITH THE
POTENTIAL FOR HIGH WINDS...HEAVY RAIN...AND POSSIBLY STRONG TO
SEVERE THUNDERSTORMS. UNSETTLED WEATHER WITH SHOWERS WILL CONTINUE
INTO THURSDAY AS THE UPPER LOW SLOWLY LIFTS OUT OF THE REGION.
IMPROVING WEATHER CONDITIONS ARE EXPECTED FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1245 PM EDT MONDAY...
BIGGEST ADJUSTMENTS TO THE FORECAST FOR THIS AFTERNOON INCLUDE
WARMER TEMPERATURES AND LESS CLOUD COVER TO THE AREA OF THE
FORECAST AREA BETWEEN AND WEST OF BLUEFIELD WV TO MARION VA. HERE
INCREASING SOUTHEAST FLOW HAS RESULTED IN A DOWNSLOPE COMPONENT
THAT IS HELPING TO ERODE THE CLOUD COVER AND INCREASE THE
TEMPERATURE. WOULD NOT BE SURPRISED IF HIGHS WILL BE IN THE MID
70S TO NEAR 80 DEGREES THIS AFTERNOON. ALSO...HAVE DOWNPLAYED THE
PRECIPITATION CHANCES THE REMAINDER OF THE AFTERNOON TO PRIMARILY
THOSE AREAS ALONG AND EAST OF THE CREST OF THE BLUE RIDGE FOR A
SLIGHT CHANCE OF MEASURABLE PRECIPITATION ALONG WITH SOME PATCHY
DRIZZLE. HAVE ALSO LOWERED EXPECTED HIGH TEMPERATURES IN AREAS
CLOSEST TO THE CREST OF THE BLUE RIDGE WHERE CLOUDY SKIES ARE
EXPECTED THE REMAINDER OF THE AFTERNOON.
AS OF 945 AM EDT MONDAY...
ONLY SOME VERY LIGHT PRECIPITATION REMAINS ACROSS THE REGION
CURRENTLY. LIGHT AMOUNTS WERE ALONG THE CREST OF THE BLUE
RIDGE...AND A SMALL AREA WAS HEADING NORTH OF BLACKSBURG...ALONG
THE WV/VA BORDER. HRRR AND RNK-WRF ARW SOLUTIONS OFFER VERY LITTLE
IN THE WAY OF PRECIPITATION THE REMAINDER OF THE DAY.
HOWEVER...THAT VALUE IS NOT ZERO. WILL CONTINUE TO HAVE A FORECAST
THAT REFLECTS SLIGHT TO SLIGHT CHANCE POPS DURING THE AFTERNOON
HOURS WITH THE BEST FOCUS STILL ALONG THE SLOPES OF THE BLUE
RIDGE. WHILE THE TRAJECTORY ANGLE IS NOT THE BEST FOR
UPSLOPE...AS 850 MB WINDS INCREASE...EVEN A COMPONENT TO UPSLOPE
WILL HELP MAINTAIN SOME LIGHT PRECIPITATION IN AT LEAST THIS
REGION.
FORECAST SURFACE BASED LIFTED INDICES AND CAPE VALUES OFFER A
SOLUTION THAT ALLOWS FOR THE POTENTIAL OF ISOLATED STORMS ALONG
THE FAR WESTERN PARTS OF THE REGION...AND ALSO THE FAR
SOUTHEASTERN PARTS OF THE REGION. HAVE RE-INTRODUCED THIS
POTENTIAL DURING THE AFTERNOON HOURS ACROSS THESE REGIONS.
HOW QUICKLY THE WEDGE ERODES STILL IS A BIG QUESTION FOR TODAY.
HAVE NOT MADE ANY NOTABLE ADJUSTMENTS TO THE FORECAST REGARDING
THIS IN TERMS OF CLOUDS AND TEMPERATURES GIVEN NO ANOMALIES AT
THIS POINT TO SUGGEST THE FORECAST WILL NOT BE ON TRACK.
AS OF 400 AM EDT MONDAY...
THE NEXT 24 HOURS WILL BE PROVERBIAL CALM BEFORE THE STORM AS WE
AWAIT THE APPROACH OF THE INTENSE SYSTEM DEVELOPING OVER THE
CENTRAL U.S. MODELS ARE IN VERY CLOSE AGREEMENT ON THE DEVELOPMENT
OF A CUT-OFF UPPER LOW OVER THE SOUTHERN PLAINS TODAY AND THEN
KICKING IT EASTWARD INTO THE MID-MISSISSIPPI VALLEY BY 12Z
TUESDAY. A STRONG (591 DM) UPPER RIDGE WILL BE POSITIONED OVER THE
SOUTHEAST ATLANTIC COAST WHICH ALSO PLAY A ROLE IN PREVENTING THE
RAPID EASTWARD SHIFT OF THE UPPER TROUGH AND ENHANCING THE MOIST
ATLANTIC AND GULF INFLOW AHEAD OF THE FRONT. THE SURFACE HIGH
ALONG THE NEW ENGLAND COAST HAT HAS BEEN RESPONSIBLE FOR THE COOL-
AIR DAMMING OVER THE WEEKEND WILL BE SLOWLY DRIFTING EAST TODAY
ALLOWING FOR WINDS TO SHIFT TO SOUTHERLY THROUGH THE DAY TODAY
ERODING THE LOW CLOUDS AND DRIZZLE. HOW QUICKLY THIS WILL OCCUR
TODAY IS ALWAYS A TRICKY ASPECT OF FORECASTING IN THIS AREA WITH
SKY COVER AND HENCE HIGH TEMPERATURES RIDING ON THE OUTCOME.
PICKED A MODEL BLEND FOR HIGH TEMPS BUT EDGED TOWARD SOMEWHAT
SLOWER EROSION WHICH RESULTS IN HIGHS RANGING FROM UPPER 60S NW TO
MID-70S SE AND ALSO FAR WEST WHERE THE WEDGE WILL ERODE MOST
QUICKLY UNDER THE INCREASING SOUTHERLY FLOW. H85 WINDS IN THAT
SAME FAR WESTERN AREA (MAINLY TAZEWELL...SMYTH..MERCER COUNTIES)
WILL BE INCREASING FROM NEAR 25 KT EARLY THIS MORNING TO THE 45-50
KT RANGE BY 12Z TUESDAY WITH SOME OF THIS WINDS MIXING DOWN DURING
THE 06-12Z PERIOD. STRONGEST WINDS LIKELY TO BE BEYOND THE 12Z
CUT-OFF FOR THIS FORECAST PERIOD WHEN A WIND ADVISORY MAY BE
NEEDED. SCATTERED SHOWERS STILL POSSIBLE TODAY AS THE AIR MASS
REMAINS QUITE MOIST AND ANY WEAK IMPULSES WILL BE CAPABLE OF
GENERATING SOME SHOWER ACTIVITY.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
AS OF 400 AM EDT MONDAY...
MODELS CONTINUE TO MAKE ADJUSTMENTS TO TIMING OF THE INTENSE
UPPER-LEVEL LOW/TROUGH SLATED TO DEVELOP TODAY ACROSS THE
SOUTHERN/CENTRAL PLAINS...THEN SPREAD EASTWARD INTO TUE. EACH
MODEL RUN FOR ALL MODELS CONTINUE TO SLOW THE ARRIVAL OF THE MAIN
LINE OF INTENSE CONVECTION INTO OUR CWA ASSOCIATED WITH THIS
SYSTEM...LIKELY OWING TO THE IMPRESSIVE DIGGING/DEVELOPMENT OF THE
SYSTEM IN RESPONSE TO A 125+KT UPPER JET AND 60-70KT LLJ. IN
ESSENCE...THE MAIN LINE OF CONVECTION ASSOCIATED WITH THIS SYSTEM
IS NEARLY 36 HOURS SLOWER THAN WHAT WAS PROGGED TWO DAYS AGO AT
THIS TIME. NOW...INSTEAD OF A 12Z TUE TIME FRAME...WE ARE LOOKING
AT A 12Z WED TO 00Z THU TIME FRAME FOR THE MAIN EFFECTS.
THUS FOR TUE...THE WEDGE WILL BEGIN TO FINALLY ERODE...BUT AGAIN
NOT LIKELY AS QUICKLY AS THE MODELS WOULD SUGGEST. PERSISTENT
UPSLOPE AND INCREASING SOUTHEAST SFC FLOW WILL RESULT IN A
CONTINUATION OF SPOTTY LIGHT RAIN SHOWERS...ESPECIALLY EAST OF THE
ALLEGHANY FRONT AND ALONG UPSLOPE AREAS OF THE BLUE RIDGE. THE
MAIN DIFFERENCE BETWEEN MON AND TUE...HOWEVER...WILL BE THAT AS
THE TROUGH DEEPENS IN THE CENTRAL U.S...AN UPPER RIDGE WILL
BRIEFLY AMPLIFY THROUGH THE SE STATES INTO NC/VA. THIS WILL PUT
MUCH OF THE CWA...EAST OF THE ALLEGHANY FRONT...IN A WARM SECTOR
WHICH SHOULD REDUCE COVERAGE OF PRECIPITATION WITH INCREASING
SUBSIDENCE ALOFT. HOWEVER...ANY PERSISTENCE OF THE WEDGE
UNDERNEATH THE UPPER HIGH WILL PROMOTE CONTINUATION OF UPSLOPE
CLOUDS AND LIGHT -SHRA AS NOTED. THUS...HAVE MAINTAINED HIGH CHC
TO LOW LIKELY POPS WEST OF THE BLUE RIDGE. AS THE DAY
PROGRESSES...UPPER SUPPORT WILL BECOME INCREASINGLY
FAVORABLE...ESPECIALLY IN WESTERN AREAS...AND INSTABILITY WILL
BEGIN TO SUPPORT THE MENTION OF TSRA WEST OF I-77 BY LATE
AFTERNOON/EVENING.
CATEGORICAL POPS ARE IN ORDER FROM WEST TO EAST ACROSS THE REGION
BETWEEN 00Z WED AND 18Z WED WITH A SCENARIO OF A VERY SLOWLY
MOVING NEARLY MERIDIONAL OR SOUTH-NORTH ORIENTED NARROW BAND OF
INTENSE CONVECTION TRANSLATING SLOWLY ACROSS THE REGION AS THE
UPPER LOW BECOMES INCREASINGLY BAROTROPIC. IN FACT...IT COULD TAKE
UNTIL LATE WED FOR THE CONVECTION TO REACH EASTERN VA...SO HAVE
THE PERIOD OF CATEGORICAL POPS A GOOD 12 HOURS FROM THAT PREVIOUSLY
INDICATED. INSTABILITY REMAINS MARGINAL...BUT THE VERY STRONG LLJ
AND PROGGED SHEAR ALONG WITH CONVECTIVE MODE SUGGEST A QLCS IS
MOST PROBABLE WITH THIS SYSTEM. THIS WILL YIELD MARGINAL AMOUNTS
OF LIGHTNING...BUT POSSIBLE BOWING SEGMENTS WHICH CAN RESULT IN
LOCALIZED AREAS OF DAMAGING WINDS AND POSSIBLY EVEN AN ISOLATED
TORNADO. SPC HAS UPGRADED MUCH OF SW VA INTO A SLIGHT RISK THROUGH
THIS PERIOD...WITH A 5 PERCENT RISK FOR THE REMAINDER OF THE CWA.
THE MAIN THREAT FOR SEVERE WILL BE WITH THE STRONG LLJ TUE
NIGHT/EARLY WED...WITH LESS THREAT FURTHER EAST AS THE JET LIFTS
NORTH OUT OF THE REGION WITH THE UPPER LOW CUTTING OFF AND
BECOMING INCREASINGLY BAROTROPIC.
HEAVY RAIN WILL ALSO BE A THREAT WITH ANY TRAINING OF ECHOES
WITHIN THE SOUTH-NORTH ORIENTED BAND...ESPECIALLY CONSIDERING MUCH
PARTS OF THE CWA...ESPECIALLY WEST OF THE BLUE RIDGE...HAVE SEEN
1-2 INCHES OF RAIN IN THE PAST FEW DAYS. PWATS ARE WELL ABOVE
SEASONAL NORMALS IN THE 1.5+ RANGE AS THE CORE OF THE EVENT MOVES
THROUGH. THE FLOOD/FLASH FLOOD THREAT IS ADDRESSED FURTHER IN THE
HYDRO SECTION BELOW.
ANOTHER THREAT WITH THIS SYSTEM WILL BE STRONG WIND GUSTS IN THE
USUAL FAVORED AREAS OF SOUTHEAST WV AND SOUTHWEST VA AS THE LLJ
TRANSLATES THROUGH THE REGION. GIVEN THE DELAYED TIMING OF THIS
TO AFT 12Z TUE WITH A SLOWER ARRIVAL OF THE UPPER LOW/STRONG LLJ
THE POTENTIAL FOR A HIGH WIND WATCH/WIND ADVISORY WOULD BE DELAYED
UNTIL 3RD PERIOD. FURTHERMORE...MODELS HAVE SHOWN A RELUCTANCE TO
BRING POTENTIAL WINDS GUSTS OF 40-50KTS DOWN TO THE SFC. FEEL THAT
A WIND ADVISORY WILL MOST CERTAINLY BE WARRANTED AND WIND GUSTS
FOR A BRIEF PERIOD MAY REACH HIGH WIND WARNING CRITERIA IN PARTS
OF MERCER AND TAZEWELL COUNTIES. HOWEVER...NO OTHER OFFICES ARE ON
BOARD WITH A WATCH AND TOO FAR OUT FOR AN ADVISORY...SO NO NPW
WILL BE ISSUED AT THIS POINT. AS WITH THE SEVERE THREAT...WILL
CONTINUE TO HIGHLIGHT THE THREAT IN THE HWO.
TEMPERATURES REMAIN PROBLEMATIC...FIRST BECAUSE OF LINGERING
EFFECTS OF THE WEDGE AND THEREAFTER BECAUSE OF THE CLOSED...COLD
CORE SLOW MOVING UPPER LOW...CYCLONIC FLOW...AND POTENTIALLY
HIGHLY VARIABLE AMOUNTS OF SUNSHINE FROM WEST OF THE MOUNTAINS TO
THE PIEDMONT. HAVE LEANED TOWARD A MODEL BLEND THROUGH THE PERIOD
AS OPPOSED TO HINGING THE TEMPERATURES ON ANY ONE MODEL. TUE
SHOULD YIELD NEAR NORMAL TEMPS WEST TO SLIGHTLY ABOVE NORMAL
EAST...GIVEN EROSION OF THE WEDGE AND STRONG SOUTHERLY FLOW. WED
SHOULD ALSO YIELD NEAR MAX TEMPS AND WELL ABOVE NORMAL MIN
TEMPS...AGAIN PRIMARILY BECAUSE OF STRONG SOUTHERLY FLOW AND
DEWPOINTS INTO THE 60S EARLY WED...WELL ABOVE NORMAL FOR MID-
OCTOBER. THU...SHOULD SEE SLIGHTLY COOLER TEMPS...ESPECIALLY WEST
OF THE BLUE RIDGE WHERE CLOUDS AND SCT SHOWERS ARE EXPECTED.
AGAIN...NO BELOW FREEZING TEMPERATURES ARE EXPECTED EVEN AFTER THE
FRONTAL PASSAGE WITH 850MB TEMPS BOTTOMING OUT IN THE +4 TO +6C
RANGE.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 430 AM EDT MONDAY...
THE REGION WILL REMAIN UNDER THE INFLUENCE OF THE DEEP CLOSED
UPPER LOW THROUGH THE LATER HALF OF THE WEEK...FINALLY LIFTING OUT
FRI-SAT. SCT SHOWERS WILL PERSIST UNDER/NEAR THE UPPER LOW WITH A
NOTABLE DIURNAL INCREASE AS DAYTIME HEATING CREATES RELATIVELY
STEEP LAPSE RATES UNDER THE COLD CORE LOW. THE BEST CHANCE FOR
SHOWERS WILL BE WEST OF THE BLUE RIDGE. A HEALTHY SHORT WAVE IS
PROGGED TO FINALLY LIFT THE UPPER LOW OUT THU AFTERNOON...BUT IN
SO DOING WILL LIKELY BRING THE BEST COVERAGE OF SHOWERS TO THE
REGION...EVEN INTO THE PIEDMONT.
FOR THE WEEKEND...FINALLY SOME IMPROVING CONDITIONS INDICATED WITH
GREATER POTENTIAL FOR SUNSHINE...EVEN ACROSS THE MOUNTAINS. MAINLY
DRY WEATHER IS EXPECTED FOR THE REST OF THE LONG RANGE PERIOD WITH
NO SIGNIFICANT WEATHER SYSTEMS EXPECTED TO IMPACT THE AREA UNTIL
EARLY NEXT WEEK. MODERATING TEMPERATURES ARE EXPECTED UNDER A
WEAK WARM ADVECTION PATTERN ON FRIDAY INTO SATURDAY BEFORE NEXT
UPSTREAM SHORT WAVE TROF SCOOTS RAPIDLY SOUTHEAST OUT OF NORTHERN
PLAINS AND INTO NEW ENGLAND LATER SATURDAY NIGHT INTO SUNDAY.
BEST DYNAMICS AND MOISTURE WITH THIS SYSTEM EXPECTED TO REMAIN WELL
TO THE NORTHWEST OF THE BLACKSBURG FORECAST AREA...SO OTHER THAN A
SLIGHT INCREASE IN MID AND HIGH LEVEL CLOUDS...ONLY SENSIBLE IMPACT
WILL BE FOR A SLIGHT REINFORCEMENT OF COOLER AIR WITH PASSAGE OF DRY
COOL FRONT...AND POSSIBLY SOME ISOLATED-WIDELY SCATTERED POST
FRONTAL UPSLOPE SHOWERS REDEVELOPING ACROSS THE WESTERN FLANKS OF
THE APPALACHIANS IN SOUTHEASTERN WEST VIRGINIA...MOST NOTABLY IN
WESTERN GREENBRIER COUNTY.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 1240 PM EDT MONDAY...
HIGH PRESSURE WEDGE REMAINS IN PLACE ALONG THE CREST OF THE BLUE
RIDGE ALONG WITH MAINLY LIFR/IFR CIGS AND IFR/MVFR VSBYS FOR LIGHT
FOG AND SOME DRIZZLE. OUTSIDE THE INFLUENCE OF THE WEDGE...ALONG
AND WEST OF A KBLF-KMKJ LINE...SCT-BKN MVFR BASED CLOUDS WERE THE
NORM AS INCREASING SOUTHEAST FLOW IS HELPING TO ERODE THE CLOUD
COVER. THIS PATTERN WILL CONTINUE THROUGH THE REMAINDER OF THE
AFTERNOON WITH PERHAPS A BIT MORE EROSION OF THE WEDGE ON ITS
EASTERN AND WESTERN FLANKS.
OVERNIGHT...LOW LEVEL WINDS WILL INCREASE SIGNIFICANTLY...PROGGED
TO REACH 40 TO 50 KTS AT 850 MB BY 12Z/8AM TUESDAY. THIS WILL
ALLOW FOR A VERY GENEROUS MOISTURE FETCH INTO THE REGION THAT WILL
YIELD UPSLOPE PRECIPITATION MAINLY IN AREAS NEAREST THE CREST OF
THE BLUE RIDGE. VSBYS AND CIGS WILL ALSO TREND LOWER IN THIS AREA.
THE INCREASING WINDS ABOVE THE WEDGE WILL YIELD LOW LEVEL WIND
SHEAR AT ALL BUT PERHAPS KBLF. HERE...OUTSIDE THE INFLUENCE OF THE
WEDGE...THE WINDS WILL REMAIN MIXED.
THROUGH THE MORNING HOURS ON TUESDAY...THE BULK OF THE ACTIVITY OF
THE APPROACHING UPPER TROUGH AND COLD FRONT WILL REMAIN TO OUR
WEST. FLIGHT CONDITIONS WILL START TO IMPROVE BY THE LATE MORNING
AS BETTER MIXING...AND EROSION OF THE WEDGE TAKES PLACE.
EXTENDED AVIATION DISCUSSION...
TUESDAY AFTERNOON INTO TUESDAY NIGHT A VERY STRONG NEGATIVELY
TILTED UPPER TROUGH WILL APPROACH AND MOVE THROUGH THE REGION.
LOOK FOR A SOUTHERLY 850 MB JET TO REACH 50 TO 60 KTS IN ADVANCE
OF THE SYSTEM. STRONG THUNDERSTORMS WITH PLENTY OF PRECIPITATION
IS EXPECTED IN ADVANCE AND CONCURRENT WITH THE FRONTAL PASSAGE
LATE TUESDAY NIGHT INTO MIDDAY WEDNESDAY.
ON WEDNESDAY AFTERNOON...THE FRONT WILL EXIT THE REGION BUT
NORTHWEST FLOW BEHIND THE SYSTEM WILL KEEP UPSLOPE CLOUDS AND RAIN
SHOWERS ACROSS SOUTHEAST WEST VIRGINIA...SOUTH INTO THE NORTHERN
MOUNTAINS OF NORTH CAROLINA THROUGH THURSDAY NIGHT AS THE CENTER
OF THE PARENT UPPER LOW SETTLES OVER PENNSYLVANIA.
BY FRIDAY...THE PRESSURE GRADIENT WILL SLACKEN AS WE TRANSITION
INTO A MORE ZONAL PATTERN. THIS WILL BE SHORT LIVED THOUGH AS OUR
NEXT GREAT LAKES TROUGH DEEPENS ON SATURDAY. WINDS WILL START TO
INCREASE AGAIN BY SATURDAY AFTERNOON.
&&
.HYDROLOGY...
AS OF 400 AM EDT MONDAY...
THE UPCOMING EVENT WILL HAVE A SIGNIFICANT HYDRO COMPONENT WITH
HEAVY RAINFALL EXPECTED ACROSS ALL RIVER BASINS MAINLY AFTER 12Z
TUESDAY AND PERSISTING INTO EARLY THURSDAY. QPF FROM HPC DURING
THIS PERIOD IS GENERALLY IN THE 2 TO 3 INCH RANGE WITH THE TYPICAL
TERRAIN ENHANCEMENTS. GEFS AND NAEFS ENSEMBLE PRECIPITATION
FORECASTS FROM THE VARIOUS RFCS STILL SHOWING CONSIDERABLE SPREAD
IN THE QPF WITH ANYWHERE FROM 1 TO 5 INCHES IN NEARLY ALL BASINS
BUT SOLUTIONS CLUSTERING MAINLY IN THE 2 TO 2.5 INCH RANGE. THE
RIVER FORECAST ENSEMBLES RESULTING FROM THIS QPF GENERATE A LOT OF
FORECASTS NEAR OR JUST BELOW ACTION STAGE WITH A FEW MEMBERS
REACHING MINOR FLOOD STAGE AND MAYBE ONE OR TWO OUTLIERS AT
MODERATE FLOOD STAGE. SO IT DOES NOT LOOK LIKE A VERY SERIOUS
RIVER FLOOD EVENT AT THIS POINT BUT CERTAINLY WILL BE WATCHED
CLOSELY. ALSO A FLASH FLOOD THREAT TO CONSIDER AS PWATS REACH 2 TO
3 STANDARD DEVIATIONS ABOVE MID-OCTOBER KRNK RAOB CLIMATOLOGY BY
WEDNESDAY MORNING RANGING FROM 1.5 TO 1.7 INCHES AT KRNK AND
SOMEWHAT HIGHER AT ROANOKE. WITH THE WIDESPREAD 2 TO 3 INCH
RAINFALL AND EMBEDDED CONVECTION THERE WILL LIKELY BE ISOLATED 4
TO 5 INCH AMOUNTS ACROSS A FEW SMALL BASINS AND POCKETS OF RAPID
RESPONSE FLOODING SEEM TO BE A REASONABLE BET. HPC CURRENTLY
SHOWING A SLIGHT RISK OF EXCESSIVE RAINFALL IN EXCESS OF FLASH
FLOOD GUIDANCE IN THE FAR WESTERN CWA BY 12Z TUE AND FOR MOST THE
REMAINDER 12Z TUE TO 12Z WED. AN ADDITIONAL FACTOR IN THE FLOOD
POTENTIAL IS THE LOW FLASH FLOOD GUIDANCE VALUES RESULTING FROM
RAINFALL SO FAR IN OCTOBER WHICH HAS REACHED 4 TO 6 INCHES IN
PARTS OF THE TENNESSEE AND NEW RIVER BASINS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...PC
NEAR TERM...DS/PC
SHORT TERM...RAB
LONG TERM...RAB/WERT
AVIATION...DS
HYDROLOGY...PC
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1248 PM EDT MON OCT 13 2014
.SYNOPSIS...
COOL HIGH PRESSURE ACROSS THE MID-ATLANTIC WILL GRADUALLY RELAX
ITS INFLUENCE ON OUR WEATHER TODAY AS SOUTHERLY FLOW INCREASES IN
ADVANCE OF A DEEPENING TROUGH OF LOW PRESSURE ACROSS THE CENTRAL
UNITED STATES. THIS TROUGH AND A STRONG SURFACE COLD FRONT WILL
MOVE ACROSS THE AREA TUESDAY NIGHT AND WEDNESDAY WITH THE
POTENTIAL FOR HIGH WINDS...HEAVY RAIN...AND POSSIBLY STRONG TO
SEVERE THUNDERSTORMS. UNSETTLED WEATHER WITH SHOWERS WILL CONTINUE
INTO THURSDAY AS THE UPPER LOW SLOWLY LIFTS OUT OF THE REGION.
IMPROVING WEATHER CONDITIONS ARE EXPECTED FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1245 PM EDT MONDAY...
BIGGEST ADJUSTMENTS TO THE FORECAST FOR THIS AFTERNOON INCLUDE
WARMER TEMPERATURES AND LESS CLOUD COVER TO THE AREA OF THE
FORECAST AREA BETWEEN AND WEST OF BLUEFIELD WV TO MARION VA. HERE
INCREASING SOUTHEAST FLOW HAS RESULTED IN A DOWNSLOPE COMPONENT
THAT IS HELPING TO ERODE THE CLOUD COVER AND INCREASE THE
TEMPERATURE. WOULD NOT BE SURPRISED IF HIGHS WILL BE IN THE MID
70S TO NEAR 80 DEGREES THIS AFTERNOON. ALSO...HAVE DOWNPLAYED THE
PRECIPITATION CHANCES THE REMAINDER OF THE AFTERNOON TO PRIMARILY
THOSE AREAS ALONG AND EAST OF THE CREST OF THE BLUE RIDGE FOR A
SLIGHT CHANCE OF MEASURABLE PRECIPITATION ALONG WITH SOME PATCHY
DRIZZLE. HAVE ALSO LOWERED EXPECTED HIGH TEMPERATURES IN AREAS
CLOSEST TO THE CREST OF THE BLUE RIDGE WHERE CLOUDY SKIES ARE
EXPECTED THE REMAINDER OF THE AFTERNOON.
AS OF 945 AM EDT MONDAY...
ONLY SOME VERY LIGHT PRECIPITATION REMAINS ACROSS THE REGION
CURRENTLY. LIGHT AMOUNTS WERE ALONG THE CREST OF THE BLUE
RIDGE...AND A SMALL AREA WAS HEADING NORTH OF BLACKSBURG...ALONG
THE WV/VA BORDER. HRRR AND RNK-WRF ARW SOLUTIONS OFFER VERY LITTLE
IN THE WAY OF PRECIPITATION THE REMAINDER OF THE DAY.
HOWEVER...THAT VALUE IS NOT ZERO. WILL CONTINUE TO HAVE A FORECAST
THAT REFLECTS SLIGHT TO SLIGHT CHANCE POPS DURING THE AFTERNOON
HOURS WITH THE BEST FOCUS STILL ALONG THE SLOPES OF THE BLUE
RIDGE. WHILE THE TRAJECTORY ANGLE IS NOT THE BEST FOR
UPSLOPE...AS 850 MB WINDS INCREASE...EVEN A COMPONENT TO UPSLOPE
WILL HELP MAINTAIN SOME LIGHT PRECIPITATION IN AT LEAST THIS
REGION.
FORECAST SURFACE BASED LIFTED INDICES AND CAPE VALUES OFFER A
SOLUTION THAT ALLOWS FOR THE POTENTIAL OF ISOLATED STORMS ALONG
THE FAR WESTERN PARTS OF THE REGION...AND ALSO THE FAR
SOUTHEASTERN PARTS OF THE REGION. HAVE RE-INTRODUCED THIS
POTENTIAL DURING THE AFTERNOON HOURS ACROSS THESE REGIONS.
HOW QUICKLY THE WEDGE ERODES STILL IS A BIG QUESTION FOR TODAY.
HAVE NOT MADE ANY NOTABLE ADJUSTMENTS TO THE FORECAST REGARDING
THIS IN TERMS OF CLOUDS AND TEMPERATURES GIVEN NO ANOMALIES AT
THIS POINT TO SUGGEST THE FORECAST WILL NOT BE ON TRACK.
AS OF 400 AM EDT MONDAY...
THE NEXT 24 HOURS WILL BE PROVERBIAL CALM BEFORE THE STORM AS WE
AWAIT THE APPROACH OF THE INTENSE SYSTEM DEVELOPING OVER THE
CENTRAL U.S. MODELS ARE IN VERY CLOSE AGREEMENT ON THE DEVELOPMENT
OF A CUT-OFF UPPER LOW OVER THE SOUTHERN PLAINS TODAY AND THEN
KICKING IT EASTWARD INTO THE MID-MISSISSIPPI VALLEY BY 12Z
TUESDAY. A STRONG (591 DM) UPPER RIDGE WILL BE POSITIONED OVER THE
SOUTHEAST ATLANTIC COAST WHICH ALSO PLAY A ROLE IN PREVENTING THE
RAPID EASTWARD SHIFT OF THE UPPER TROUGH AND ENHANCING THE MOIST
ATLANTIC AND GULF INFLOW AHEAD OF THE FRONT. THE SURFACE HIGH
ALONG THE NEW ENGLAND COAST HAT HAS BEEN RESPONSIBLE FOR THE COOL-
AIR DAMMING OVER THE WEEKEND WILL BE SLOWLY DRIFTING EAST TODAY
ALLOWING FOR WINDS TO SHIFT TO SOUTHERLY THROUGH THE DAY TODAY
ERODING THE LOW CLOUDS AND DRIZZLE. HOW QUICKLY THIS WILL OCCUR
TODAY IS ALWAYS A TRICKY ASPECT OF FORECASTING IN THIS AREA WITH
SKY COVER AND HENCE HIGH TEMPERATURES RIDING ON THE OUTCOME.
PICKED A MODEL BLEND FOR HIGH TEMPS BUT EDGED TOWARD SOMEWHAT
SLOWER EROSION WHICH RESULTS IN HIGHS RANGING FROM UPPER 60S NW TO
MID-70S SE AND ALSO FAR WEST WHERE THE WEDGE WILL ERODE MOST
QUICKLY UNDER THE INCREASING SOUTHERLY FLOW. H85 WINDS IN THAT
SAME FAR WESTERN AREA (MAINLY TAZEWELL...SMYTH..MERCER COUNTIES)
WILL BE INCREASING FROM NEAR 25 KT EARLY THIS MORNING TO THE 45-50
KT RANGE BY 12Z TUESDAY WITH SOME OF THIS WINDS MIXING DOWN DURING
THE 06-12Z PERIOD. STRONGEST WINDS LIKELY TO BE BEYOND THE 12Z
CUT-OFF FOR THIS FORECAST PERIOD WHEN A WIND ADVISORY MAY BE
NEEDED. SCATTERED SHOWERS STILL POSSIBLE TODAY AS THE AIR MASS
REMAINS QUITE MOIST AND ANY WEAK IMPULSES WILL BE CAPABLE OF
GENERATING SOME SHOWER ACTIVITY.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
AS OF 400 AM EDT MONDAY...
MODELS CONTINUE TO MAKE ADJUSTMENTS TO TIMING OF THE INTENSE
UPPER-LEVEL LOW/TROUGH SLATED TO DEVELOP TODAY ACROSS THE
SOUTHERN/CENTRAL PLAINS...THEN SPREAD EASTWARD INTO TUE. EACH
MODEL RUN FOR ALL MODELS CONTINUE TO SLOW THE ARRIVAL OF THE MAIN
LINE OF INTENSE CONVECTION INTO OUR CWA ASSOCIATED WITH THIS
SYSTEM...LIKELY OWING TO THE IMPRESSIVE DIGGING/DEVELOPMENT OF THE
SYSTEM IN RESPONSE TO A 125+KT UPPER JET AND 60-70KT LLJ. IN
ESSENCE...THE MAIN LINE OF CONVECTION ASSOCIATED WITH THIS SYSTEM
IS NEARLY 36 HOURS SLOWER THAN WHAT WAS PROGGED TWO DAYS AGO AT
THIS TIME. NOW...INSTEAD OF A 12Z TUE TIME FRAME...WE ARE LOOKING
AT A 12Z WED TO 00Z THU TIME FRAME FOR THE MAIN EFFECTS.
THUS FOR TUE...THE WEDGE WILL BEGIN TO FINALLY ERODE...BUT AGAIN
NOT LIKELY AS QUICKLY AS THE MODELS WOULD SUGGEST. PERSISTENT
UPSLOPE AND INCREASING SOUTHEAST SFC FLOW WILL RESULT IN A
CONTINUATION OF SPOTTY LIGHT RAIN SHOWERS...ESPECIALLY EAST OF THE
ALLEGHANY FRONT AND ALONG UPSLOPE AREAS OF THE BLUE RIDGE. THE
MAIN DIFFERENCE BETWEEN MON AND TUE...HOWEVER...WILL BE THAT AS
THE TROUGH DEEPENS IN THE CENTRAL U.S...AN UPPER RIDGE WILL
BRIEFLY AMPLIFY THROUGH THE SE STATES INTO NC/VA. THIS WILL PUT
MUCH OF THE CWA...EAST OF THE ALLEGHANY FRONT...IN A WARM SECTOR
WHICH SHOULD REDUCE COVERAGE OF PRECIPITATION WITH INCREASING
SUBSIDENCE ALOFT. HOWEVER...ANY PERSISTENCE OF THE WEDGE
UNDERNEATH THE UPPER HIGH WILL PROMOTE CONTINUATION OF UPSLOPE
CLOUDS AND LIGHT -SHRA AS NOTED. THUS...HAVE MAINTAINED HIGH CHC
TO LOW LIKELY POPS WEST OF THE BLUE RIDGE. AS THE DAY
PROGRESSES...UPPER SUPPORT WILL BECOME INCREASINGLY
FAVORABLE...ESPECIALLY IN WESTERN AREAS...AND INSTABILITY WILL
BEGIN TO SUPPORT THE MENTION OF TSRA WEST OF I-77 BY LATE
AFTERNOON/EVENING.
CATEGORICAL POPS ARE IN ORDER FROM WEST TO EAST ACROSS THE REGION
BETWEEN 00Z WED AND 18Z WED WITH A SCENARIO OF A VERY SLOWLY
MOVING NEARLY MERIDIONAL OR SOUTH-NORTH ORIENTED NARROW BAND OF
INTENSE CONVECTION TRANSLATING SLOWLY ACROSS THE REGION AS THE
UPPER LOW BECOMES INCREASINGLY BAROTROPIC. IN FACT...IT COULD TAKE
UNTIL LATE WED FOR THE CONVECTION TO REACH EASTERN VA...SO HAVE
THE PERIOD OF CATEGORICAL POPS A GOOD 12 HOURS FROM THAT PREVIOUSLY
INDICATED. INSTABILITY REMAINS MARGINAL...BUT THE VERY STRONG LLJ
AND PROGGED SHEAR ALONG WITH CONVECTIVE MODE SUGGEST A QLCS IS
MOST PROBABLE WITH THIS SYSTEM. THIS WILL YIELD MARGINAL AMOUNTS
OF LIGHTNING...BUT POSSIBLE BOWING SEGMENTS WHICH CAN RESULT IN
LOCALIZED AREAS OF DAMAGING WINDS AND POSSIBLY EVEN AN ISOLATED
TORNADO. SPC HAS UPGRADED MUCH OF SW VA INTO A SLIGHT RISK THROUGH
THIS PERIOD...WITH A 5 PERCENT RISK FOR THE REMAINDER OF THE CWA.
THE MAIN THREAT FOR SEVERE WILL BE WITH THE STRONG LLJ TUE
NIGHT/EARLY WED...WITH LESS THREAT FURTHER EAST AS THE JET LIFTS
NORTH OUT OF THE REGION WITH THE UPPER LOW CUTTING OFF AND
BECOMING INCREASINGLY BAROTROPIC.
HEAVY RAIN WILL ALSO BE A THREAT WITH ANY TRAINING OF ECHOES
WITHIN THE SOUTH-NORTH ORIENTED BAND...ESPECIALLY CONSIDERING MUCH
PARTS OF THE CWA...ESPECIALLY WEST OF THE BLUE RIDGE...HAVE SEEN
1-2 INCHES OF RAIN IN THE PAST FEW DAYS. PWATS ARE WELL ABOVE
SEASONAL NORMALS IN THE 1.5+ RANGE AS THE CORE OF THE EVENT MOVES
THROUGH. THE FLOOD/FLASH FLOOD THREAT IS ADDRESSED FURTHER IN THE
HYDRO SECTION BELOW.
ANOTHER THREAT WITH THIS SYSTEM WILL BE STRONG WIND GUSTS IN THE
USUAL FAVORED AREAS OF SOUTHEAST WV AND SOUTHWEST VA AS THE LLJ
TRANSLATES THROUGH THE REGION. GIVEN THE DELAYED TIMING OF THIS
TO AFT 12Z TUE WITH A SLOWER ARRIVAL OF THE UPPER LOW/STRONG LLJ
THE POTENTIAL FOR A HIGH WIND WATCH/WIND ADVISORY WOULD BE DELAYED
UNTIL 3RD PERIOD. FURTHERMORE...MODELS HAVE SHOWN A RELUCTANCE TO
BRING POTENTIAL WINDS GUSTS OF 40-50KTS DOWN TO THE SFC. FEEL THAT
A WIND ADVISORY WILL MOST CERTAINLY BE WARRANTED AND WIND GUSTS
FOR A BRIEF PERIOD MAY REACH HIGH WIND WARNING CRITERIA IN PARTS
OF MERCER AND TAZEWELL COUNTIES. HOWEVER...NO OTHER OFFICES ARE ON
BOARD WITH A WATCH AND TOO FAR OUT FOR AN ADVISORY...SO NO NPW
WILL BE ISSUED AT THIS POINT. AS WITH THE SEVERE THREAT...WILL
CONTINUE TO HIGHLIGHT THE THREAT IN THE HWO.
TEMPERATURES REMAIN PROBLEMATIC...FIRST BECAUSE OF LINGERING
EFFECTS OF THE WEDGE AND THEREAFTER BECAUSE OF THE CLOSED...COLD
CORE SLOW MOVING UPPER LOW...CYCLONIC FLOW...AND POTENTIALLY
HIGHLY VARIABLE AMOUNTS OF SUNSHINE FROM WEST OF THE MOUNTAINS TO
THE PIEDMONT. HAVE LEANED TOWARD A MODEL BLEND THROUGH THE PERIOD
AS OPPOSED TO HINGING THE TEMPERATURES ON ANY ONE MODEL. TUE
SHOULD YIELD NEAR NORMAL TEMPS WEST TO SLIGHTLY ABOVE NORMAL
EAST...GIVEN EROSION OF THE WEDGE AND STRONG SOUTHERLY FLOW. WED
SHOULD ALSO YIELD NEAR MAX TEMPS AND WELL ABOVE NORMAL MIN
TEMPS...AGAIN PRIMARILY BECAUSE OF STRONG SOUTHERLY FLOW AND
DEWPOINTS INTO THE 60S EARLY WED...WELL ABOVE NORMAL FOR MID-
OCTOBER. THU...SHOULD SEE SLIGHTLY COOLER TEMPS...ESPECIALLY WEST
OF THE BLUE RIDGE WHERE CLOUDS AND SCT SHOWERS ARE EXPECTED.
AGAIN...NO BELOW FREEZING TEMPERATURES ARE EXPECTED EVEN AFTER THE
FRONTAL PASSAGE WITH 850MB TEMPS BOTTOMING OUT IN THE +4 TO +6C
RANGE.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 430 AM EDT MONDAY...
THE REGION WILL REMAIN UNDER THE INFLUENCE OF THE DEEP CLOSED
UPPER LOW THROUGH THE LATER HALF OF THE WEEK...FINALLY LIFTING OUT
FRI-SAT. SCT SHOWERS WILL PERSIST UNDER/NEAR THE UPPER LOW WITH A
NOTABLE DIURNAL INCREASE AS DAYTIME HEATING CREATES RELATIVELY
STEEP LAPSE RATES UNDER THE COLD CORE LOW. THE BEST CHANCE FOR
SHOWERS WILL BE WEST OF THE BLUE RIDGE. A HEALTHY SHORT WAVE IS
PROGGED TO FINALLY LIFT THE UPPER LOW OUT THU AFTERNOON...BUT IN
SO DOING WILL LIKELY BRING THE BEST COVERAGE OF SHOWERS TO THE
REGION...EVEN INTO THE PIEDMONT.
FOR THE WEEKEND...FINALLY SOME IMPROVING CONDITIONS INDICATED WITH
GREATER POTENTIAL FOR SUNSHINE...EVEN ACROSS THE MOUNTAINS. MAINLY
DRY WEATHER IS EXPECTED FOR THE REST OF THE LONG RANGE PERIOD WITH
NO SIGNIFICANT WEATHER SYSTEMS EXPECTED TO IMPACT THE AREA UNTIL
EARLY NEXT WEEK. MODERATING TEMPERATURES ARE EXPECTED UNDER A
WEAK WARM ADVECTION PATTERN ON FRIDAY INTO SATURDAY BEFORE NEXT
UPSTREAM SHORT WAVE TROF SCOOTS RAPIDLY SOUTHEAST OUT OF NORTHERN
PLAINS AND INTO NEW ENGLAND LATER SATURDAY NIGHT INTO SUNDAY.
BEST DYNAMICS AND MOISTURE WITH THIS SYSTEM EXPECTED TO REMAIN WELL
TO THE NORTHWEST OF THE BLACKSBURG FORECAST AREA...SO OTHER THAN A
SLIGHT INCREASE IN MID AND HIGH LEVEL CLOUDS...ONLY SENSIBLE IMPACT
WILL BE FOR A SLIGHT REINFORCEMENT OF COOLER AIR WITH PASSAGE OF DRY
COOL FRONT...AND POSSIBLY SOME ISOLATED-WIDELY SCATTERED POST
FRONTAL UPSLOPE SHOWERS REDEVELOPING ACROSS THE WESTERN FLANKS OF
THE APPALACHIANS IN SOUTHEASTERN WEST VIRGINIA...MOST NOTABLY IN
WESTERN GREENBRIER COUNTY.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 630 AM EDT MONDAY...
VARIABLE FLIGHT CONDITIONS LIKELY TO BE THE RULE TODAY AT THE
TERMINALS AS DEPARTING HIGH PRESSURE STRUGGLES TO MAINTAIN
THE LOW CLOUDS AND EASTERLY FLOW WHILE THE TROUGH DEVELOPING
OUT WEST BRINGS INCREASING SOUTHERLY FLOW ALOFT TRYING TO MIX
DOWN TO THE SURFACE AND SCOUR OUT THE LOW CLOUDS. SHOULD SEE VERY
SLOW IMPROVEMENT IN CIGS/VBSYS AS THIS OCCURS TODAY. UNLIKELY
TO SEE MUCH IN THE WAY OF VFR BUT AT LEAST MVFR BY LATER IN THE
DAY OR EVENING. ANY PARTIAL CLEARING THAT TAKES PLACE LATE TODAY
OR OVERNIGHT LIKELY TO BRIEF AS EXTENSIVE CLOUDINESS FROM THE
CENTRAL U.S. SYSTEM WILL BE EDGING INTO THE WESTERN PORTIONS OF
THE AREA BY THAT TIME...WHICH MAY ACT TO INHIBIT FOG DEVELOPMENT
TOWARD MORNING.
EXTENDED AVIATION DISCUSSION...
TUESDAY INTO TUESDAY NIGHT A VERY STRONG NEGATIVELY TILTED UPPER
TROUGH WILL APPROACH AND MOVE THROUGH THE REGION. LOOK FOR A
SOUTHERLY 850 MB JET TO REACH 50 TO 70 KTS IN ADVANCE OF THE
SYSTEM. STRONG THUNDERSTORMS WITH PLENTY OF PRECIPITATION IS
EXPECTED IN ADVANCE AND CONCURRENT WITH THE FRONTAL PASSAGE LATE
TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING.
ON WEDNESDAY...THE FRONT WILL EXIT THE REGION BUT NORTHWEST FLOW
BEHIND THE SYSTEM WILL KEEP UPSLOPE CLOUDS AND RAIN SHOWERS ACROSS
SOUTHEAST WEST VIRGINIA...SOUTH INTO THE NORTHERN MOUNTAINS OF
NORTH CAROLINA THROUGH THURSDAY AS THE CENTER OF THE PARENT UPPER
LOW SETTLES OVER PENNSYLVANIA.
BY FRIDAY...THE PRESSURE GRADIENT WILL SLACKEN AS WE TRANSITION
INTO A MORE ZONAL PATTERN.
&&
.HYDROLOGY...
AS OF 400 AM EDT MONDAY...
THE UPCOMING EVENT WILL HAVE A SIGNIFICANT HYDRO COMPONENT WITH
HEAVY RAINFALL EXPECTED ACROSS ALL RIVER BASINS MAINLY AFTER 12Z
TUESDAY AND PERSISTING INTO EARLY THURSDAY. QPF FROM HPC DURING
THIS PERIOD IS GENERALLY IN THE 2 TO 3 INCH RANGE WITH THE TYPICAL
TERRAIN ENHANCEMENTS. GEFS AND NAEFS ENSEMBLE PRECIPITATION
FORECASTS FROM THE VARIOUS RFCS STILL SHOWING CONSIDERABLE SPREAD
IN THE QPF WITH ANYWHERE FROM 1 TO 5 INCHES IN NEARLY ALL BASINS
BUT SOLUTIONS CLUSTERING MAINLY IN THE 2 TO 2.5 INCH RANGE. THE
RIVER FORECAST ENSEMBLES RESULTING FROM THIS QPF GENERATE A LOT OF
FORECASTS NEAR OR JUST BELOW ACTION STAGE WITH A FEW MEMBERS
REACHING MINOR FLOOD STAGE AND MAYBE ONE OR TWO OUTLIERS AT
MODERATE FLOOD STAGE. SO IT DOES NOT LOOK LIKE A VERY SERIOUS
RIVER FLOOD EVENT AT THIS POINT BUT CERTAINLY WILL BE WATCHED
CLOSELY. ALSO A FLASH FLOOD THREAT TO CONSIDER AS PWATS REACH 2 TO
3 STANDARD DEVIATIONS ABOVE MID-OCTOBER KRNK RAOB CLIMATOLOGY BY
WEDNESDAY MORNING RANGING FROM 1.5 TO 1.7 INCHES AT KRNK AND
SOMEWHAT HIGHER AT ROANOKE. WITH THE WIDESPREAD 2 TO 3 INCH
RAINFALL AND EMBEDDED CONVECTION THERE WILL LIKELY BE ISOLATED 4
TO 5 INCH AMOUNTS ACROSS A FEW SMALL BASINS AND POCKETS OF RAPID
RESPONSE FLOODING SEEM TO BE A REASONABLE BET. HPC CURRENTLY
SHOWING A SLIGHT RISK OF EXCESSIVE RAINFALL IN EXCESS OF FLASH
FLOOD GUIDANCE IN THE FAR WESTERN CWA BY 12Z TUE AND FOR MOST THE
REMAINDER 12Z TUE TO 12Z WED. AN ADDITIONAL FACTOR IN THE FLOOD
POTENTIAL IS THE LOW FLASH FLOOD GUIDANCE VALUES RESULTING FROM
RAINFALL SO FAR IN OCTOBER WHICH HAS REACHED 4 TO 6 INCHES IN
PARTS OF THE TENNESSEE AND NEW RIVER BASINS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...PC
NEAR TERM...DS/PC
SHORT TERM...RAB
LONG TERM...RAB/WERT
AVIATION...PC
HYDROLOGY...PC