Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 09/23/13
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
1050 AM PDT SAT SEP 21 2013
.DISCUSSION...AS OF 08:43 AM PDT SATURDAY...IMPRESSIVE RAINFALL
NUMBERS ALREADY IN THE SANTA CRUZ MOUNTAINS AND NORTH
BAY...UP TO THREE QUARTERS OF AN INCH AT MOUNT SAINT HELENA.
OROGRAPHIC EFFECTS STRONGLY IN FORCE AT TIME IN WARM ADVECTIVE
SECTOR OF APPROACHING BAROCLINIC ZONE.
MODELS STRUGGLING WITH PRECIP AMOUNTS WITH 12Z NAM
UNDER FORECASTING AMOUNTS. PREFER HRRR SHORT TERM FORECAST THOUGH
TIMING HAS BEEN A LITTLE BIT SLOW WITH MODEL. 00Z ECMWF AND HRRR
APPEAR TO HAVE THE MOST REALISTIC SOLUTIONS WITH QPF.
INITIAL FRONTAL BOUNDARY HAS WASHED OUT OVER MONTEREY COUNTY WITH
MAIN BOUNDARY SHOWING CLOUD TOP COOLING AND DEVELOPMENT AS IT
MOVES INTO NORTH BAY. RAINFALL SHOULD SPREAD EAST AND SOUTHWARD
INTO THE BAY AREA THROUGH THE REST OF THE MORNING. APPEARS TO BE
SIGNIFICANT CONVECTION WITH OFFSHORE BOUNDARY...SO INCLUDED SLIGHT
CHANCE THUNDERSTORMS ACROSS MOST OF CWFA DOWN TO ABOUT MONTEREY.
PRECIPITATION WITH FRONTAL BOUNDARY WILL MOVE SOUTH INTO COASTAL
MONTEREY COUNTY THIS AFTERNOON...THOUGH SYSTEM WILL GRADUALLY
WEAKEN. BOUNDARY EXPECTED TO MOVE EAST AND SOUTH OF THE AREA BY
EVENING WITH RAPID CLEARING FROM NORTHWEST TO SOUTHEAST.
MADE SOME SIGNIFICANT UPDATES IN TODAYS FORECAST PERIOD WITH
REGARDS TO QPF AND POPS...INCREASING AMOUNTS AS RADAR AND
SATELLITE IMAGERY INDICATE DYNAMIC SYSTEM APPROACHING COAST.
LOOKING AT CONVECTIVE NATURE OF CELLS OFFSHORE ALREADY SHOWING ON
RADAR...WOULD NOT BE SURPRISED TO SEE A FEW HEAVIER SHOWERS AND
EVEN A THUNDERSTORM BY AFTERNOON.
&&
.PREV DISCUSSION...AS OF 3:39 AM PDT SATURDAY...SHOWER ACTIVITY IS
CONTINUING ACROSS THE NORTH BAY EARLY THIS MORNING WITH RAIN
TOTALS SO FAR FROM ABOUT 0.10 TO 0.30 FOR MARIN AND SONOMA
COUNTIES. IN GENERAL ONLY SPOTTY PRECIP HAS MADE IT SOUTH OF THE
GOLDEN GATE SO FAR WITH A FEW HUNDREDTHS IN THE HILLS OF SAN
MATEO AND SANTA CRUZ COUNTY. WERE STILL IN THE WARM SECTOR OF THE
SYSTEM WITH SOUTHERLY WINDS AT THE BUOYS AND OVER LAND KEEPING
OVERNIGHT TEMPERATURES FROM THE UPPER 50S TO MID 60S.
A POTENT SHORTWAVE IS JUST ABOUT TO PASS OVER 38N/130W AND IS
POISED TO TAKE AIM ON THE GREATER BAY AREA LATER THIS MORNING AND
AFTERNOON AS THE UPPER TROUGH AXIS PASSES OVERHEAD. LATEST MODEL
TRENDS HAVE TRENDED SLIGHTLY WETTER AND EXPECT SHOWER ACTIVITY TO
INCREASE FROM MID-MORNING THROUGH EARLY AFTERNOON AS IT SHIFTS
SOUTHWARD FROM THE NORTH BAY...THROUGH THE GREATER BAY AREA AND
THEN DISSIPATES WITH LITTLE OR NO PRECIP SOUTH OF MONTEREY.
HIGHEST RAIN TOTALS WILL BE IN THE NORTH BAY WITH A TENTH OF AN
INCH OR SO FOR THE BAY AREA TAPERING TO A FEW HUNDREDTHS AROUND
MONTEREY BAY. GIVEN STRENGTH OF SHORTWAVE AND STEEP LAPSE RATES
ALOFT AS WELL AS HIGH SURFACE DEWPOINTS WILL KEEP THE THREAT OF
THUNDERSTORMS GOING IN THE NORTH BAY TODAY.
SHOWER ACTIVITY SHOULD RAPIDLY WIND DOWN BY EARLY EVENING AND END
BY SUNSET AS THE VORT MAX SHIFTS EASTWARD AND SOLAR HEATING ENDS.
AFTER A CHILLY START SUNDAY LOOKS TO BE A NICE DAY WITH CRYSTAL
BLUE SKIES IN THE WAKE OF THE UPPER TROUGH AND SEASONABLY MILD
TEMPS FROM THE 60S COAST TO 70S INLAND.
NO BIG WEATHER CHANGES FOR MONDAY WITH MOSTLY CLEAR AND SEASONABLE
WEATHER FORECAST.
NEXT SHORTWAVE APPROACHES NORCAL BY TUESDAY BUT ANY PRECIP WILL
STAY EAST OF THE BAY AREA AS THE MAIN SHORTWAVE SHIFTS WELL
INLAND. THE PATTERN WILL PRODUCE SOME BREEZY CONDITIONS LATER
TUESDAY INTO WEDS. SURFACE PATTERN WILL THEN SHIFT A THERMAL
TROUGH TOWARDS THE COAST WEDS NIGHT INTO THURSDAY WITH A TIGHT
PRESSURE GRADIENT SETTING UP ACROSS NORCAL. MODELS HAVE BEEN
KEYING IN ON THE 06-12Z THURSDAY TIME FRAME FOR SOME STRONGER
NORTH TO NORTHEAST WINDS. WILL CONTINUE TO MONITOR THAT TREND AND
WILL HAVE TO SEE HOW MUCH DRYING OCCURS AFTER TODAYS RAIN BEFORE
THE WINDS BLOW AS TO HOW THAT WILL IMPACT FIRE WEATHER CONDITIONS.
LIVE FUEL MOISTURES WONT BE IMPACTED BY TODAYS RAIN AS THE PLANTS
ARE DORMANT.
&&
.AVIATION...AS OF 10:45 AM PDT SATURDAY...FORECAST CONFIDENCE IS
REMAINING LOW. A MID LEVEL TROUGH AXIS PUSHING TOWARDS THE AREA
CURRENTLY BRINGING LOTS OF SHOWERS AND EVEN OCCASIONAL MODERATE TO
HEAVY RAIN AT TERMINALS. CEILINGS HAVING A DIFFICULT TIME FALLING
BELOW VFR DESPITE RAINFALL BUT SOME OCCASIONAL IFR OBSERVED IN
HEAVIER RAIN SHOWERS. EXPECT RAIN THREAT TO TAPER OFF AT TERMINALS
BY 00Z SUN AND WIND SHIFT TO NORTHWEST SHORTLY THEREAFTER.
GENERALLY VFR BUT SOME MVFR/IFR CIGS OVERNIGHT AT TERMINALS. LOW
PROBABILITY OF THUNDER THIS MORNING AND EARLY AFTERNOON SO WILL
NOT CARRY MENTION IN TAF.
VICINITY OF KSFO...DESPITE HEAVY RAIN AT TIMES...CIGS REMAIN VFR.
WILL KEEP THIS TREND WITH GRADUAL DECREASE INTO MVFR CATEGORY.
BAND OF MODERATE TO HEAVY RAIN WILL EXIT THE AREA BY 23Z AND WIND
SHIFT TO WEST WILL OCCUR SHORTLY THEREAFTER. MAY BE BRIEFLY GUSTY
WITH WEST WIND SHIFT. CIGS WILL BOUNCE AROUND MVFR TO VFR
OVERNIGHT WITH SOME INDICATION OF A PERIOD OF MVFR CIGS AROUND
SUNRISE BUT NOT A GOOD CONFIDENCE IN THE FORECAST OVERALL.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR THIS MORNING WILL FALL INTO MVFR
CATEGORY AS CLOUDINESS AND SHOWERS APPROACH SLOWLY FROM THE
NORTHWEST. WILL EXPECT MVFR/IFR CONDITIONS AFTER 21-23Z SAT AND
EXPECTING PERSISTENT IN THAT RANGE THROUGH 12Z SUN. WEST WIND
SHIFT EARLY SUNDAY MORNING BUT LOW CONFIDENCE IN CIG IMPROVEMENT.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...NONE.
&&
$$
PUBLIC FORECAST: KBB
AVIATION/MARINE: JOHNSON
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
903 AM PDT SAT SEP 21 2013
.DISCUSSION...AS OF 08:43 AM PDT SATURDAY...IMPRESSIVE RAINFALL
NUMBERS ALREADY IN THE SANTA CRUZ MOUNTAINS AND NORTH
BAY...UP TO THREE QUARTERS OF AN INCH AT MOUNT SAINT HELENA.
OROGRAPHIC EFFECTS STRONGLY IN FORCE AT TIME IN WARM ADVECTIVE
SECTOR OF APPROACHING BAROCLINIC ZONE.
MODELS STRUGGLING WITH PRECIP AMOUNTS WITH 12Z NAM
UNDER FORECASTING AMOUNTS. PREFER HRRR SHORT TERM FORECAST THOUGH
TIMING HAS BEEN A LITTLE BIT SLOW WITH MODEL. 00Z ECMWF AND HRRR
APPEAR TO HAVE THE MOST REALISTIC SOLUTIONS WITH QPF.
INITIAL FRONTAL BOUNDARY HAS WASHED OUT OVER MONTEREY COUNTY WITH
MAIN BOUNDARY SHOWING CLOUD TOP COOLING AND DEVELOPMENT AS IT
MOVES INTO NORTH BAY. RAINFALL SHOULD SPREAD EAST AND SOUTHWARD
INTO THE BAY AREA THROUGH THE REST OF THE MORNING. APPEARS TO BE
SIGNIFICANT CONVECTION WITH OFFSHORE BOUNDARY...SO INCLUDED SLIGHT
CHANCE THUNDERSTORMS ACROSS MOST OF CWFA DOWN TO ABOUT MONTEREY.
PRECIPITATION WITH FRONTAL BOUNDARY WILL MOVE SOUTH INTO COASTAL
MONTEREY COUNTY THIS AFTERNOON...THOUGH SYSTEM WILL GRADUALLY
WEAKEN. BOUNDARY EXPECTED TO MOVE EAST AND SOUTH OF THE AREA BY
EVENING WITH RAPID CLEARING FROM NORTHWEST TO SOUTHEAST.
MADE SOME SIGNIFICANT UPDATES IN TODAYS FORECAST PERIOD WITH
REGARDS TO QPF AND POPS...INCREASING AMOUNTS AS RADAR AND
SATELLITE IMAGERY INDICATE DYNAMIC SYSTEM APPROACHING COAST.
LOOKING AT CONVECTIVE NATURE OF CELLS OFFSHORE ALREADY SHOWING ON
RADAR...WOULD NOT BE SURPRISED TO SEE A FEW HEAVIER SHOWERS AND
EVEN A THUNDERSTORM BY AFTERNOON.
&&
.PREV DISCUSSION...AS OF 3:39 AM PDT SATURDAY...SHOWER ACTIVITY IS
CONTINUING ACROSS THE NORTH BAY EARLY THIS MORNING WITH RAIN
TOTALS SO FAR FROM ABOUT 0.10 TO 0.30 FOR MARIN AND SONOMA
COUNTIES. IN GENERAL ONLY SPOTTY PRECIP HAS MADE IT SOUTH OF THE
GOLDEN GATE SO FAR WITH A FEW HUNDREDTHS IN THE HILLS OF SAN
MATEO AND SANTA CRUZ COUNTY. WERE STILL IN THE WARM SECTOR OF THE
SYSTEM WITH SOUTHERLY WINDS AT THE BUOYS AND OVER LAND KEEPING
OVERNIGHT TEMPERATURES FROM THE UPPER 50S TO MID 60S.
A POTENT SHORTWAVE IS JUST ABOUT TO PASS OVER 38N/130W AND IS
POISED TO TAKE AIM ON THE GREATER BAY AREA LATER THIS MORNING AND
AFTERNOON AS THE UPPER TROUGH AXIS PASSES OVERHEAD. LATEST MODEL
TRENDS HAVE TRENDED SLIGHTLY WETTER AND EXPECT SHOWER ACTIVITY TO
INCREASE FROM MID-MORNING THROUGH EARLY AFTERNOON AS IT SHIFTS
SOUTHWARD FROM THE NORTH BAY...THROUGH THE GREATER BAY AREA AND
THEN DISSIPATES WITH LITTLE OR NO PRECIP SOUTH OF MONTEREY.
HIGHEST RAIN TOTALS WILL BE IN THE NORTH BAY WITH A TENTH OF AN
INCH OR SO FOR THE BAY AREA TAPERING TO A FEW HUNDREDTHS AROUND
MONTEREY BAY. GIVEN STRENGTH OF SHORTWAVE AND STEEP LAPSE RATES
ALOFT AS WELL AS HIGH SURFACE DEWPOINTS WILL KEEP THE THREAT OF
THUNDERSTORMS GOING IN THE NORTH BAY TODAY.
SHOWER ACTIVITY SHOULD RAPIDLY WIND DOWN BY EARLY EVENING AND END
BY SUNSET AS THE VORT MAX SHIFTS EASTWARD AND SOLAR HEATING ENDS.
AFTER A CHILLY START SUNDAY LOOKS TO BE A NICE DAY WITH CRYSTAL
BLUE SKIES IN THE WAKE OF THE UPPER TROUGH AND SEASONABLY MILD
TEMPS FROM THE 60S COAST TO 70S INLAND.
NO BIG WEATHER CHANGES FOR MONDAY WITH MOSTLY CLEAR AND SEASONABLE
WEATHER FORECAST.
NEXT SHORTWAVE APPROACHES NORCAL BY TUESDAY BUT ANY PRECIP WILL
STAY EAST OF THE BAY AREA AS THE MAIN SHORTWAVE SHIFTS WELL
INLAND. THE PATTERN WILL PRODUCE SOME BREEZY CONDITIONS LATER
TUESDAY INTO WEDS. SURFACE PATTERN WILL THEN SHIFT A THERMAL
TROUGH TOWARDS THE COAST WEDS NIGHT INTO THURSDAY WITH A TIGHT
PRESSURE GRADIENT SETTING UP ACROSS NORCAL. MODELS HAVE BEEN
KEYING IN ON THE 06-12Z THURSDAY TIME FRAME FOR SOME STRONGER
NORTH TO NORTHEAST WINDS. WILL CONTINUE TO MONITOR THAT TREND AND
WILL HAVE TO SEE HOW MUCH DRYING OCCURS AFTER TODAYS RAIN BEFORE
THE WINDS BLOW AS TO HOW THAT WILL IMPACT FIRE WEATHER CONDITIONS.
LIVE FUEL MOISTURES WONT BE IMPACTED BY TODAYS RAIN AS THE PLANTS
ARE DORMANT.
&&
.AVIATION...AS OF 5:00 AM PDT SATURDAY...VERY TRICKY LOW
CONFIDENCE FORECAST TODAY AS CIGS HAVE BEEN ALL OVER THE PLACE SO
FAR TONIGHT. MODELS ARE IN GOOD AGREEMENT AND BRING RAIN TO THE
NORTH BAY AFTER 12Z AND DOWN TO ABOUT MONTEREY 18 TO 21Z. STILL AM
EXPECTING MOSTLY IFR TO LOW MVFR CONDITIONS THROUGH MOST OF THE
MORNING WITH GUSTS LIKELY DURING ANY SHOWERS. CONDITIONS IMPROVE
AFTER THE FRONTAL PASSAGE.
VICINITY OF KSFO...CURRENTLY AROUND VFR LEVELS BUT SHOULD DROP BACK
TO MVFR/IFR FOR MOST OF THE MORNING. RAIN CHANCES FROM 15 TO
AROUND 23Z WITH GUSTS POSSIBLE DURING ANY SHOWERS. SW WINDS
THIS MORNING WITH GUSTS TO 20KT BY AFTERNOON. EVEN STRONGER
WESTERLY WINDS BY THE EVENING. VFR RETURNS BY TONIGHT. LOW CONFIDENCE.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR SHOULD SWITCH TO MVFR BY LATER
THIS MORNING. RAIN FORECAST TO REMAIN NORTH OF MONTEREY BAY
ALTHOUGH ENOUGH OF A CHANCE IN THE FORECAST SO ADDED VCSH TO BOTH
TERMINALS. LOW TO MODERATE CONFIDENCE.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...NONE.
&&
$$
PUBLIC FORECAST: KBB
AVIATION/MARINE: BELL
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AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
528 AM PDT SAT SEP 21 2013
.SYNOPSIS...
A STORM SYSTEM MOVING THROUGH THE AREA TODAY WILL BRING COOL TEMPERATURES
AND RELATIVELY WET WEATHER. THUNDERSTORMS ARE POSSIBLE ACROSS THE
SACRAMENTO VALLEY IN THE AFTERNOON AND EVENING. DRY WEATHER SUNDAY
INTO MONDAY THEN MOUNTAIN SHOWERS POSSIBLE TUESDAY INTO WEDNESDAY.
BREEZY CONDITIONS LATE TUESDAY THROUGH EARLY FRIDAY. BELOW NORMAL
TEMPERATURES THROUGH MID WEEK WITH DRYER AND WARMER CONDITIONS
TOWARDS THE END OF THE WEEK.
.DISCUSSION...
A WEAKENING COLD FRONT PASSING THROUGH THE AREA IS PRODUCING SOME
SCATTERED RAIN SHOWERS NORTH OF INTERSTATE 80. THE HRRR MODEL
SHOWS A MUCH MORE DEFINED SW TO NE BAND OF HEAVIER RAIN MOVING
INLAND REACHING REDDING BY MID MORNING AND THE DELTA AROUND NOON.
RADAR SHOWS A PORTION OF THIS BAND CURRENTLY ALONG THE NORTHWEST
CALIFORNIA COAST ASSOCIATED WITH THE MAIN TROUGH. THIS BAND WILL
GRADUALLY SHIFT EASTWARD WITH THE REST OF THE SACRAMENTO VALLEY
AND NORTHERN SAN JOAQUIN SEEING THIS HEAVIER PRECIPITATION BY
AROUND NOON. PEAK PRECIPITATION IN THE SIERRA SHOULD BE REACHED
LATE IN THE AFTERNOON. SNOW LEVELS AROUND 7500 FEET IN THE SIERRA COULD
BRING A DUSTING OF SNOW TO HIGHER MOUNTAINS. MOUNTAINS TO THE
NORTH COULD SEE LIGHT SNOW DOWN TO 7000 FEET OR SO.
CAPE AND LI LEVELS SUGGEST AN AREA OF FAIRLY STRONG INSTABILITY
CENTERED BETWEEN CHICO AND YUBA CITY BY MID DAY. EXPECT HEAVIER
SHOWERS AND THUNDERSTORMS TO DEVELOP IN THAT AREA THROUGH THE
AFTERNOON AND INTO THE EARLY EVENING. SOME THUNDERSTORMS MAY ALSO
DEVELOP ELSEWHERE IN THE SACRAMENTO VALLEY. BREAKS IN THE CLOUDS
IN THE AFTERNOON MAY ALLOW FOR ADDITIONAL DESTABILIZATION BUT THIS
IS STILL UNCERTAIN. THE GFS SOUNDING AROUND CHICO HAS CAPE REACHING OVER
700 J/KG BY LATE AFTERNOON AND MODIFYING THE SOUNDING SUGGESTS
LEVELS OVER 800 J/KG. THE NAM IS NOT AS IMPRESSIVE AND HAS CAPE
LEVELS AROUND 450 J/KG. GENERAL SHEAR LEVELS AT 0-1 KM AND 0-6 KM
DO NOT LOOK TOO IMPRESSIVE (PEAKING AROUND 9 AND 36 M/S BY 2 PM)
BUT COULD BE SEE SOME DECENT SHEAR DEVELOP LOCALLY IN THE BUTTE
COUNTY AREA WITH A CONVERGENCE AREA. WILL HAVE TO WATCH THIS SETUP
CLOSELY TO SEE IF THE POTENTIAL FOR SOME SEVERE STORMS DEVELOPS.
PRECIPITATION WILL CONTINUE INTO THE EVENING THEN SHOULD SHIFT
EASTWARD AFTER MIDNIGHT WITH JUST SOME LINGERING MOUNTAIN SHOWERS,
MAINLY OVER THE SIERRA. THE TROUGH PULLS EAST OF THE AREA QUICKLY
ON SUNDAY, WITH SOME MORNING FOG POSSIBLE IN MOUNTAIN VALLEYS. SKIES
SHOULD CLEAR BY MIDDAY. TEMPERATURES WILL REBOUND A BIT, BUT LOOK
TO REMAIN A BIT BELOW NORMAL A BRINGING A CRISP FIRST DAY OF FALL.
HIGHS MONDAY AND TUESDAY WILL BE MORE MILD AND SEASONABLE. THE
FLOW ALOFT REMAINS ACTIVE ACROSS THE EASTERN PACIFIC GOING INTO
NEXT WEEK. PRECIPITATION ON MONDAY SHOULD MAINLY BE TO THE NORTH
OF THE SHASTA COUNTY MOUNTAINS, WITH SOME LIGHT SHOWERS OVER THAT
AREA POSSIBLE MONDAY NIGHT INTO TUESDAY AS AN INSIDE SLIDER SYSTEM
DROPS DOWN IN NE CALIFORNIA/N NEVADA. EK
.EXTENDED DISCUSSION (WEDNESDAY THROUGH SATURDAY)
BY WEDNESDAY THE TROUGH WILL BE CENTERED OVER THE GREAT BASIN WITH
CHANCES OF SOME PRECIPITATION OVER THE SIERRA. WITH THE AREA
BEING ON THE BACK PORTION OF THE TROUGH WEDNESDAY AND THURSDAY,
NORTHERLY WINDS WILL PICK UP AND BECOME BREEZY THROUGH THE VALLEY.
THIS COULD BRING A RETURN OF INCREASED FIRE DANGER TO THE AREA
INTO FRIDAY WITH LOWERING HUMIDITY LEVELS. CONDITIONS WILL BE DRY
AND COOL WITH BELOW AVERAGE TEMPERATURES. EK
.EXTENDED DISCUSSION (WEDNESDAY THROUGH SATURDAY)
BY WEDNESDAY THE TROUGH WILL BE CENTERED OVER THE GREAT BASIN WITH
CHANCES OF SOME PRECIPITATION OVER THE SIERRA. WITH THE AREA
BEING ON THE BACK PORTION OF THE TROUGH WEDNESDAY AND THURSDAY,
NORTHERLY WINDS WILL PICK UP AND BECOME BREEZY THROUGH THE VALLEY.
THIS COULD BRING A RETURN OF INCREASED FIRE DANGER TO THE AREA
INTO FRIDAY WITH LOWERING HUMIDITY LEVELS. CONDITIONS WILL BE DRY
AND COOL WITH BELOW AVERAGE TEMPERATURES. EK
&&
.AVIATION...
FRONTAL SYSTEM WILL MOVE THROUGH NORCAL THIS AFTERNOON. ISOLATED
TO SCATTERED THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON OVER
MUCH OF NOCAL. GENERALLY VFR/MVFR WITH LOCAL IFR CONDITIONS ARE
EXPECTED IN THE VALLEY IN -SHRA AND IFR/LIFR CONDITIONS OVER THE
MOUNTAINS. SNOW LEVELS WILL LOWER TO AROUND 7500 FT BY AFTERNOON.
SOUTH TO SOUTHWEST WINDS 10-20 KT WITH LOCAL GUSTS TO 40 KTS OVER
THE MOUNTAINS.
&&
.STO WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1114 PM MDT FRI SEP 20 2013
.UPDATE...
ISSUED AT 616 PM MDT FRI SEP 20 2013
RAN A QUICK UPDATE TO REDUCE CLOUD COVER ACROSS THE STATE.
SCATTERED CLOUDS SHOULD HANG ON ALONG THE NEW MEXICO BORDER
THROUGH 10 PM...WITH CLEAR SKIES ELSEWHERE. ALSO ADDED THE MENTION
OF PATCHY FOG OVER THE SAN LUIS VALLEY LATE TONIGHT INTO SATURDAY
MORNING...BASED ON THE LATEST MODEL DATA AND BUFKIT SOUNDINGS. MOZLEY
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 331 PM MDT FRI SEP 20 2013
QUIET WEATHER OVER THE AREA TODAY BENEATH TRANSIENT UPPER RIDGE.
STRATUS HAS CLEARED OUT OF MOST OF THE SE PLAINS...THOUGH COOLER AIR
MASS OVER THE REGION HAS KEPT SE PLAINS CAPPED. STILL WAITING TO
SEE IF SUFFICIENT HEATING WILL OCCUR TO POP A THUNDERSTORM OR TWO
ALONG THE CREST OF THE SOUTHERN SANGRES...AND PERHAPS ACROSS THE
EASTERN SAN JUAN MOUNTAINS...BUT SO FAR CONVECTION HAS HAD A HARD
TIME GETTING GOING...WITH AIRMASS LOOKING TOO DRY ACROSS THE SW MTS
WHERE DEW POINTS HAVE DROPPED INTO THE 20S...AND TOO CAPPED AND COOL
FOR THE SOUTHERN SANGRES. EACH SUCCESSIVE HRRR RUN HAS BACKED OFF
WITH QPF FOR THOSE AREAS...SO HAVE TRIMMED BACK POPS INTO THE SILENT
CATEGORY.
SOUTHWEST FLOW INCREASES OVER THE AREA FOR SUNDAY. NAM12 PICKS UP
SOME LOW LEVEL MOISTURE AND GENERATES SOME OROGRAPHIC SHOWERS ACROSS
THE SOUTHWEST MTS EARLY SATURDAY MORNING. THIS COULD BE A BIT
OVERDONE...BUT GFS HINTS AT THIS TOO SO WILL MAINTAIN SOME ISOLATED
SHOWERS FOR THAT AREA. BY AFTERNOON...MODELS SHOW SOME ISOLATED
THUNDERSTORMS SPREADING NORTH AND EASTWARD INTO THE SAWATCH AND
MOSQUITO RANGES AND THE SANGRES. OTHERWISE...TEMPERATURES SHOULD
REBOUND NICELY BACK INTO THE 80S FOR THE SE PLAINS WITH A MIX OF 60S
AND 70S FOR THE MOUNTAIN AREAS. SOUTHERLY WINDS WILL INCREASE
ACROSS THE AREA AS THE LEE TROF DEEPENS AHEAD OF THE NEXT
APPROACHING TROF. STRONGEST WINDS WILL BE ACROSS THE HIGHER PEAKS
IN THE AFTERNOON AND ALONG THE FAR EASTERN BORDER ON THE EAST SIDE
OF THE SFC TROF AXIS. BOTH AREAS COULD SEE GUSTS IN THE 25-30 KT
RANGE. -KT
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 331 PM MDT FRI SEP 20 2013
.SATURDAY NIGHT THROUGH SUNDAY NIGHT...TROUGH MOVES ACROSS THE
REGION SUNDAY AFTERNOON AND EVENING. MODELS HAVE SOME DIFFERENCES
ON THE STRENGTH OF THE TROUGH. THE NAM IS THE WEAKEST WHILE THE EC
IS THE STRONGEST. MAIN CONCERNS WITH TROUGH PASSAGE WOULD BE SNOW
LEVELS ALONG THE CONTINENTAL DIVIDE AND WINDS OVER THE EASTERN
MOUNTAINS AND PLAINS. MOST OF THE PRECIPITATION OVER THE
CONTINENTAL DIVIDE REGION OCCURS AHEAD OF THE COLDEST AIR
ALOFT...AND SNOW IS MOSTLY LIMITED TO THE HIGHEST PEAKS. SNOW
LEVELS COULD FALL BELOW TREE LINE BEFORE PRECIPITATION ENDS FOR
SOME ACCUMULATIONS. IF THE TROUGH IS DEEPER...MORE SNOW COULD FALL
BELOW TREE LINE. THE BEST CHANCES FOR SNOW BELOW TREELINE WILL BE
SUNDAY EVENING. SECOND CONCERN WILL BE WINDS. GUSTY SOUTH TO
SOUTHWEST WINDS WILL DEVELOP AHEAD OF THE TROUGH SUNDAY ON THE
PLAINS. GFS AND EC HAVE THE 500MB TROUGH CUT OFF BRIEFLY AS IT
LIFTS NORTHEAST INTO NEBRASKA. HAVE SOME CONCERNS FOR A BRIEF
PERIOD OF STRONG WINDS SUNDAY EVENING OVER THE EASTERN MOUNTAINS
AND INTERSTATE 25 CORRIDOR. MODELS DO NOT HAVE STRONG WINDS AT
THIS TIME...BUT HAVE SEEN WINDY CONDITIONS WITH SIMILAR PATTERNS.
.MONDAY THROUGH WEDNESDAY...DRY AND WARM PATTERN DEVELOPS BEHIND
DEPARTING TROUGH AND AHEAD OF THE NEXT TROUGH. BREEZY TO WINDY
CONDITIONS ARE POSSIBLE ON WEDNESDAY AS SOUTHWEST FLOW ALOFT
STRENGTHENS AHEAD OF THE NEXT TROUGH MOVING INTO THE PACIFIC
NORTHWEST.
.THRUSDAY AND FRIDAY...EC AND GFS HAVE THE TROUGH OVER THE
NORTHWEST US MOVING NORTHEASTWARD ACROSS THE NORTHERN ROCKIES.
REGION WILL BE ON THE SOUTHERN END OF THE TROUGH. BOTH MODELS
SUGGEST A COLD FRONT IN THE REGION...WITH THE POTENTIAL FOR SOME
UPSLOPE ON THE EASTERN PLAINS. TOO EARLY TO GET VERY SPECIFIC ON
DETAILS SUCH AS THE LOCATION OF THE FRONT...STRENGTH OF EASTERLY
UPSLOPE FLOW AND STRENGTH OF THE TROUGH. GRIDS HAVE A MODEST
COOLING TREND WITH SOME ISOLATED POPS. --PGW--
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1112 PM MDT FRI SEP 20 2013
VFR CONDITIONS AT KPUB AND KCOS THROUGH THE NEXT 24 HOURS
DIURNALLY DRIVEN WINDS. MODELS HAVE BACKED OFF ON THE PROBABILITY
OF FOG LATE TONIGHT AT KALS...BUT GIVEN THERE IS STILL SOME
MOISTURE ACROSS THE SAN LUIS VALLEY...FEEL THERE MAY STILL BE SOME
PATCHY FOG 12-15Z/SAT WITH REDUCED VIS AND CIGS. OTHERWISE EXPECT
VFR CONDITIONS AT KALS. MOZLEY
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MOZLEY
SHORT TERM...KT
LONG TERM...PGW
AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
950 PM EDT SUN SEP 22 2013
.DISCUSSION...
DIURNAL CONVECTION SPENT ITSELF BY SUNSET...LIMITED IMPACT OUTSIDE
OF ISOLD SFC WND GUSTS OVER 30MPH AND LCL RAINFALL BTWN 1.0"-1.5"
ALONG AND N OF THE I-4 CORRIDOR. REMNANT PENCIL THIN BAND OF SHRAS
OVER THE SRN COASTAL WATERS WILL HAVE HAVE NO IMPACT ON LAND OUTSIDE
OF THE IMMEDIATE COAST OF MARTIN COUNTY...AND EVEN THEN THAT
POTENTIAL WILL DISSIPATE BY MIDNIGHT.
STALLED WEAK FRONTAL BOUNDARY OVER THE FL PANHANDLE WILL COMBINE
WITH A WEAK LOW LVL RIDGE AXIS OVER THE CENTRAL/SRN PENINSULA TO
MAINTAIN A LIGHT BUT STEADY WRLY FLOW ALOFT. MID/UPR LVL DEBRIS
CLOUD DECK WILL PERSIST OVERNIGHT AS THE WRLY FLOW ALOFT PUSHES
POCKETS OF CONVECTION ONSHORE OVER THE NATURE COAST. HOWEVER...
THESE TWO WX FEATURES HAVE WORKED TO VIRTUALLY CANCEL OUT ANY
MEANINGFUL SFC/BNDRY LYR PGRAD AS MOST SFC OBS IN CENTRAL FL
REPORTED CALM WINDS AS OF 01Z.
EVENING SOUNDINGS SHOW COPIOUS MOISTURE ACRS THE FL PENINSULA WITH
KJAX/KTBW/KMFL ALL REPORTING PWAT VALUES AOA 2.0". RUC ANALYSIS
SHOWING A FEW POCKETS OF H85-H50 VORTICITY OVER THE ERN GOMEX THAT
WILL PUSH ACRS CENTRAL FL OVERNIGHT...ADDING WEAK MID LVL SUPPORT.
PRESENCE OF THE FRONTAL BOUNDARY MAY ADD JUST ENOUGH LOW LVL
CONVERGENCE TO THE EQUATION TO WARRANT SMALL POPS IN THE FCST.
WILL UPDATE ZONES TO REDUCE POPS TO THE SLGT CHC CATEGORY ADVERTISED
BY THE AFTN PACKAGE. NO OTHER SIG CHANGES NECESSARY.
&&
.AVIATION...
THRU 23/14Z...PREVAILING VFR/CALM SFC WNDS ALL SITES...CIGS AOA
FL120 N OF KISM-KTIX...SLGT CHC BRIEF MVFR SHRAS VCNTY KLEE. BTWN
23/14Z-23/18Z...E/SE SFC WNDS AOB 12KTS...VCSH INTERIOR SITES. BTWN
23/18Z-23/24Z...NMRS MVFR SHRAS/SCT IFR TSRAS ALL SITES...AFT 23/20Z
SLGT CHC LIFR +TSRAS COASTAL SITES WITH SFC WND G35KTS...STORM
MOTION ENE ARND 15KTS.
&&
.MARINE...
STALLED FRONTAL BOUNDARY OVR THE FL PANHANDLE COUPLED WITH A WEAK
SFC HIGH PRES RIDGE OVER THE CENTRAL PENINSULA WILL GENERATE A LIGHT
TO GENTLE WRLY BREEZE OVER THE LCL ATLC. SEAS AOB 2FT NEARSHORE AND
2-3FT OFFSHORE. THIN LINE OF SHRAS OVER THE SRN LEG MVG E/SE WILL
DISSIPATE THRU MIDNIGHT.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
FORECAST/AVIATION...BRAGAW
RADAR/IMPACT WX.....BLOTTMAN
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
940 PM EDT Sun Sep 22 2013
.NEAR TERM [Through Tonight]...
Based on a combination of RAP objective analyses and offshore obs
(including one ship), it appears there is a mesoscale low around
1006mb just to the south of Destin. A surface front lingers to the
ENE of that, situated right over the Florida Panhandle. The area
also remains in an elongated deformation axis between 800-400mb, and
in the right entrance region of a slightly anticyclonically curved
upper level jet streak. This jet streak is fairly strong - GOES
satellite winds are as high as 76 knots over parts of C GA. Finally,
there does appear to be at least some modest low-level moisture flux
over the Florida Panhandle and Big Bend with the RAP showing the
nose of 850mb stronger moisture transport more or less right over
Tallahassee. This is confirmed by WSW 25 knot winds at that level on
the TLH VWP. Essentially, there are a number of ingredients to force
continued precipitation across the southern part of our area,
especially when you consider our 00 UTC observed PWAT (on the
sounding) was 2.08".
None of the models indicate focused heavy precipitation, but it is
reasonable to expect continued light to moderate rain showers or
areas of rain to continue to affect our Florida zones, and perhaps
the southern row of Georgia zones. We increased the PoP gradient
across the area to produce a dry overnight forecast across the far
northern parts of the area, with likely PoPs over the south.
Expected rain and cloud cover should keep temperatures relatively
warm tonight, so the lows were mainly kept in the low 70s.
Recent runs of the HRRR do show increased convective development
near the front along the Big Bend / Apalachee Bay coastline between
09-14 UTC. This possibility will need to be monitored closely given
the model is also showing PWATs in that area of 2.2 to 2.4 inches,
relatively slow storm motions, and a deep warm cloud layer around
14,000 feet - all ingredients for low-topped, efficient tropical
rain showers. Because of this, we have inserted heavy rain wording
into areas with "likely PoPs".
&&
.SHORT TERM [Monday Through Tuesday Night]...
Frontal boundary is forecast to become diffuse on Monday as
shortwave ridging builds briefly over the region. However, there
should be enough lingering moisture and low-level convergence for
some scattered showers and isolated thunderstorms, especially near
the coast and over the coastal waters. By Tuesday, a trough will
slide east into the Ohio Valley and help to re-activate what is
left of the frontal boundary. This should lead to another round of
moderate to occasionally heavy rainfall late Tuesday into Tuesday
night.
With plenty of cloud cover expected and light east to northeast
flow through midweek, expect high temperatures to hold in the mid
80s for most locations, very close to climo for late September.
&&
.LONG TERM [Wednesday through Sunday]...
Upper trough is forecast to exit the east coast during the day on
Wednesday, which should push the bulk of the forcing for precip
off the east coast as well. Thus, expect rainfall to taper off
from west to east during the day. For the latter half of the week,
a significant ridge is forecast to develop from the central Gulf
Coast northward into the Ohio Valley. At the surface, high
pressure centered over New England will nose down the eastern
seaboard into the northeastern Gulf. This should allow for a
progressively cooler and drier airmass to push into the region by
late in the week, with noticably cooler high temperatures and
pleasant morning lows.
&&
.AVIATION [through 00 UTC Tuesday]...
Continued unsettled conditions expected across the region as surface
front remains stalled across the FL panhandle and moist flow will
persist along and south of the front. This will result in MVFR
prevailing at KTLH, KECP AND KVLD for much of the period. All sites
could see restrictions due to low cigs and vsby later tonight and
early Monday morning. Although some VFR conditions Monday
afternoon, unsettled weather will maintain a chance of showers and
tstms, especially over north FL and far south GA.
&&
.MARINE...
Update: a SCEC headline was added for tonight as several objective
analyses place 15-20 knot winds over a sizeable portion of the
coastal waters this evening. Remainder of the previous discussion
is included below...
A frontal boundary will settle south over the waters tonight and
weaken on Monday. Light and variable winds Monday morning will
become easterly and increase slightly Monday night as high
pressure builds north of the waters. Weak low pressure will pass
across the waters by the middle of the week. At this time, winds
are forecast to remain below headline criteria.
&&
.FIRE WEATHER...
Hazardous fire weather conditions are not expected in the
foreseeable future.
&&
.HYDROLOGY...
Roughly 1 to 3 inches of rain has fallen across the region this
weekend, with the highest amounts close to the coast. Over the
next several days, another 2 to 3 inches will be possible with
locally higher amounts. This will be enough to generate minor rises
on area rivers. With the current forecast, widespread riverine
flooding appears unlikely. However, some localized flooding issues
may develop (especially in urban areas) if heavy rain can become
focused enough spatially and temporally.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 72 86 71 86 73 / 70 40 30 50 60
Panama City 75 87 75 85 73 / 70 40 30 60 60
Dothan 68 87 69 86 68 / 10 30 20 50 60
Albany 69 85 67 85 70 / 10 20 10 30 60
Valdosta 71 84 68 86 72 / 80 40 20 40 60
Cross City 72 86 70 86 72 / 60 60 40 60 50
Apalachicola 77 85 77 84 76 / 70 50 40 60 60
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...Lamers
SHORT TERM...Camp
LONG TERM...Camp
AVIATION...Evans
MARINE...Lamers/Camp
FIRE WEATHER...Harrigan
HYDROLOGY...Lamers/Camp
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
355 PM EDT SAT SEP 21 2013
.SYNOPSIS...
ISSUED AT 1022 AM EDT SAT SEP 21 2013
HIGH PRESSURE WILL BE OVER THE REGION THIS WEEKEND PROVIDING US
WITH A COOL WEEKEND. SUNNY TO MOSTLY CLOUDY IN AREAS TODAY WITH
HIGH TEMPERATURES ONLY IN THE LOWER 60S NEAR LAKE MICHIGAN TO THE
LOWER 70S NEAR THE OHIO RIVER. SKIES TONIGHT WILL BE MAINLY CLEAR
ALLOWING TEMPERATURES TO DROP DOWN INTO THE 40S. TOMORROW SKIES
WILL BE SUNNY WITH HIGH TEMPERATURES RANGING FROM THE LOWER 60S IN
SOUTHERN MICHIGAN TO AROUND 70 ALONG THE OHIO RIVER.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 354 PM EDT SAT SEP 21 2013
BROKEN STRATOCU DECK IS CONTINUING TO EXPAND ACROSS THE AREA AS COLD
AIR ADVECTION CONTINUES. THE COLDEST PORTION OF THIS AIRMASS WILL
ADVECT OVERHEAD TONIGHT WHICH WILL ALLOW TEMPERATURES TO DROP INTO
THE MID 40S. THE EXCEPTION WILL BE IN WESTERN AREAS WHERE LAKE
EFFECT CLOUD COVER WILL KEEP TEMPERATURES IN THE UPPER 40S. WENT
WITH A BLEND OF THE BCSREF AND BCEURO FOR OVERNIGHT LOWS AS THEY
WERE BOTH ON THE WARMER SIDE OF GUIDANCE. HAVE ELECTED FOR OVERNIGHT
LOWS A FEW DEGREES HIGHER DUE TO CONCERN OF SCATTERED CLOUDCOVER
PERSISTING ACROSS THE AREA TONIGHT AS WELL AS SLIGHTLY HIGHER
FORECAST DEWPOINTS. STRATOCU DECK ACROSS WISCONSIN HAS BEEN VERY
PERSISTENT TODAY AND BOTH THE RAP AND HRRR SHOW LITTLE DISSIPATION
AS IT ADVECTS OUR WAY OVERNIGHT. ON THE OTHER HAND...THE LAST FEW
FRAMES OF VISIBLE SATELLITE MAY BE HINTING AT SOME DRY AIR
ENTRAINMENT ON THE WESTERN EDGE OF THIS DECK. RAP/HRRR/NAM ARE ALL
INDICATING POTENTIAL FOR LAKE EFFECT RAIN SHOWERS AFTER MIDNIGHT AS
A SHORTWAVE DROPS THROUGH MICHIGAN...BUT HAVE KEPT FORECAST DRY
GIVEN LOWERING/STRENGTHENING INVERSION...DRY AIR ABOVE 850 MB...AND
SHALLOW FORECAST CLOUD DEPTH.
SUNDAY WILL BE COOL AND MOSTLY SUNNY AS HIGH PRESSURE SLIDES ACROSS
THE GREAT LAKES AND CYCLONIC FLOW ALOFT COMES TO AN END. CU RULE
VALUES IN THE WEST INDICATE THE POTENTIAL FOR SOME LAKE EFFECT CLOUD
COVER FOR THE FIRST PORTION OF THE DAY...BUT EVEN THIS WILL COME TO
AN END BY MID DAY ONCE WARM AIR ADVECTION ARRIVES.
&&
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 354 PM EDT SAT SEP 21 2013
UPR LEVEL RIDGE OVER THE PLAINS THIS AFTN WILL MOVE EAST TO THE WRN
GRTLKS SUNDAY NIGHT. THIS RIDGE SHOULD BECOME NRLY STNRY OVER THE
GRTLKS MON-TUE AS A DEEP CUT-OFF LOW FORMS OVER SERN CANADA. STRONG
SHRTWV MOVG ONTO THE WEST COAST THIS AFTN IS EXPECTED TO MOVE EAST
TO THE MS VALLEY TUE. COMBINATION OF ENCOUNTER WITH STALLED RIDGE
AND SHEARING ASSOCIATED WITH ANOTHER STRONG SHRTWV MOVG INTO THE
MEAN WRN TROF WILL WEAKEN THE LEAD SHRTWV AS IT APPROACHES OUR AREA.
SHOULD BE SOME INCREASE IN MOISTURE/CLOUDINESS AS THIS SYSTEM MOVES
THROUGH THE AREA TUE NGT/WED BUT AIRMASS EXPECTED TO REMAIN STABLE
WITH RATHER WARM MID/UPR LEVELS SO KEPT FCST DRY THROUGH THIS
TIMEFRAME.
RIDGE SHOULD REBUILD OVER THE AREA THU-FRI AS THE NEXT STRONG SHRTWV
CURRENTLY LOCATED OVER THE GULF OF ALASKA MOVES ACROSS THE ROCKIES.
12Z MEDIUM RANGE MODELS CONT TO HAVE CONSIDERABLE DIFFERENCE ON
TIMING/EVOLUTION OF THE TROF BY SATURDAY WITH ECMWF SHEARING SYSTEM
NE ACROSS THE NRN PLAINS/UPR GRTLKS INTO MANITOBA/ONTARIO WHILE
GFS/GEFS MAINTAIN A STRONGER UPR TROF/SFC CDFNT MOVG EAST INTO THE
MID/UPR MS VALLEY. BOTH MODELS HAVE TRENDED TOWARD A MORE PERSISTENT
RIDGE NEXT WEEKEND ACROSS THE GRTLKS OVER THE PAST 24HRS SO PREFER
ECMWF FARTHER WEST SOLUTION IN THIS REGARD AND THUS KEPT FCST FOR
SAT DRY FOR NOW.
TEMPS SHOULD BE A BIT BLO NORMAL AT THE START OF THE PERIOD WITH
LOWS IN THE L-M40S AND HIGHS IN THE M-U60S MONDAY. A SLOW WARMING
TREND EXPECTED THROUGH THE WEEK AS UPR RIDGE BUILDS INTO THE AREA
WITH ABOVE NORMAL TEMPS MID-LATE WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 152 PM EDT SAT SEP 21 2013
BREEZY NORTHWEST WINDS ARE USHERING A COOLER AIRMASS INTO THE AREA.
WITH COLD TEMPS ALOFT... BKN/OVC IFR STRATOCU DECK HAS DEVELOPED
THIS AFTERNOON AND WILL CONTINUE THROUGH THE EVENING. EXPECT THE
CLOUDS TO SCATTER OUT OVERNIGHT AT KFWA...BUT LAKE EFFECT CLOUDS
WILL KEEP CLOUD COVER MORE PERSISTENT AT KSBN. ALL CEILINGS EXPECTED
TO REMAIN IFR THROUGH THE PERIOD.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...BEACH HAZARDS STATEMENT THROUGH LATE TONIGHT FOR INZ003.
MI...BEACH HAZARDS STATEMENT THROUGH LATE TONIGHT FOR MIZ077.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 4 AM EDT SUNDAY FOR LMZ043-046.
&&
$$
SYNOPSIS...LOTHAMER
SHORT TERM...BENTLEY
LONG TERM...JT
AVIATION...BENTLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1245 PM CDT SAT SEP 21 2013
.UPDATE...
ISSUED AT 1245 PM CDT SAT SEP 21 2013
VISIBLE SATELLITE INDICATES THE AREA OF STRATUS HAS PUSHED
SOUTHWARD INTO EXTREME NW IL. HOWEVER...THE WESTERN EDGE OF THE
STRATUS FROM EASTERN MN INTO EXTREME NORTHEAST IA WAS BEGINNING TO
ERODE AS HIGH PRESSURE BUILDS IN FROM THE PLAINS. SKIES SHOULD BE
PARTLY TO MOSTLY CLOUDY EARLY THIS AFTERNOON IN EXTREME NW IL BUT
THEN SKIES WILL BECOME MOSTLY SUNNY. ELSEWHERE ACROSS THE CWA ONLY
A FEW TO SCATTERED FLAT CUMULUS.
CURRENT TEMPERATURES RANGED FROM THE UPPER 50S TO UPPER 60S ON
TARGET FOR THE MID 60S TO LOWER 70S LATER THIS AFTERNOON.
UPDATE ISSUED AT 1050 AM CDT SAT SEP 21 2013
PLEASANT FALL-LIKE DAY IN PROGRESS WITH CURRENT TEMPERATURES IN
THE MID 50S TO LOWER 60S. THESE READINGS APPEAR ON TARGET FOR
AFTERNOON HIGHS IN THE MID 60S TO LOWER 70S.
I AM WATCHING AN AREA OF STRATUS ACROSS MUCH OF WI AND EASTERN MN
WHERE THE LOW LEVELS ARE QUITE MOIST. THESE CLOUDS ARE SPREADING
SOUTHWARD BUT ALSO WILL BE RUNNING INTO DRIER AIR. OUR NW IL
COUNTIES LOOK VULNERABLE TO HAVING AT LEAST PARTLY SUNNY SKIES AND
HAVE INCREASED THE SKY GRIDS FOR THAT AREA. ELSEWHERE SCATTERED
CUMULUS/STRATOCUMULUS EXPECTED.
&&
.SYNOPSIS...
ISSUED AT 302 AM CDT SAT SEP 21 2013
FRIDAYS COLD FRONT STRETCHED FROM THE JAMES BAY SOUTHWARD TO KDTW TO
KDAY TO KMKL WITH SURFACE HIGH PRESSURE STRETCHING FROM SOUTHERN MANITOBA
SOUTHWARD TO THE TEXAS PANHANDLE. COOL...DRY AIR CONTINUED TO DROP
SOUTHWARD INTO THE UPPER MIDWEST FROM SOUTHERN CANADA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 302 AM CDT SAT SEP 21 2013
THE 500 HPA TROUGH AXIS HAS SHIFTED EASTWARD INTO CENTRAL ILLINOIS
AND WISCONSIN THIS MORNING WITH NORTHWEST FLOW ALOFT ACROSS THE
REGION. STRATUS WAS UPSTREAM OF THE REGION ACROSS EASTERN NORTH
DAKOTA AND WESTERN MINNESOTA. THIS AREA OF CLOUDS IS REPRESENTED
WELL BY 850 HPA RH. THE 00 UTC GFS AND ECMWF BOTH DEPICT THIS AREA
OF CLOUDS DISSIPATING OR GRAZING THE CORNER OF NORTHWEST ILLINOIS
LATER THIS MORNING WHILE THE RAP DEPICTS THE MOISTURE
OVERSPREADING THE REGION. THE RAP HAS TOO MUCH MOISTURE IN THE LOW
LEVELS AND WILL THUS KEEP CLOUD COVER DOWN ACROSS THE REGION THIS
MORNING. OTHERWISE HIGH PRESSURE WILL SLOW BUILD SOUTHWARD ACROSS
THE REGION DURING THE DAY ON SATURDAY. SKIES WILL BE MOSTLY SUNNY
WITH A FEW CU DEVELOPING. A PLEASANT DAY WITH HIGH TEMPERATURES
FROM THE MID 60S ALONG HIGHWAY 20 TO AROUND 70 ACROSS SOUTHEAST
IOWA AND NORTHWEST MISSOURI WHICH IS 10 DEGREES BELOW NORMAL FOR
MID SEPTEMBER.
HIGH PRESSURE WILL BE SITTING OVER THE REGION SATURDAY NIGHT INTO
SUNDAY MORNING WITH CLEAR SKIES AND STRONG RADIATIONAL COOLING. KEPT
LOW TEMPERATURES FOR SUNDAY MORNING THE SAME AS PREVIOUS SHIFTS. A
CHILLY MORNING ON SUNDAY WITH TEMPERATURES REMAINING BELOW NORMAL.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 302 AM CDT SAT SEP 21 2013
A CONSISTENTLY PLEASANT FALL WEATHER FORECAST IS IN STORE FOR SUNDAY
THROUGH THURSDAY...AS DRY WEATHER DOMINATES THE MIDWEST WEATHER.
THIS WILL INITIALLY BE THROUGH A COOL GREAT LAKES HIGH
PRESSURE...ONE THAT IS BUILDING IN TODAY. THE RESULTING WEATHER
ASSOCIATED WITH THIS HIGH WILL BE SEVERAL DAYS OF LIGHT EASTERLY
FLOW AT LOW LEVELS...AND VERY LARGE DIURNAL DAILY TRENDS. GUIDANCE
CONTINUES TO BE COOLING IN THE PAST FEW DAYS FOR SUNDAY THROUGH
TUESDAY...AND WE WILL CONTINUE TO FORECAST NEAR THE COOLER SIDE OF
OVERNIGHT LOWS...AND NEAR THE MEAN OF GUIDANCE HIGHS. THIS RESULTS
IN LOWS MAINLY IN THE LOWER 40S EAST TO UPPER 40S WEST SUNDAY
NIGHT...AND UPPER 40S/LOW 50S MONDAY NIGHT. SUNDAY THROUGH
TUESDAY...HIGHS WILL GRADUALLY INCREASE FROM THE LOWER 70S...TO MID
70S. IN ALL...VERY PLEASANT WEATHER.
A MOISTURE STARVED UPPER LOW WILL WEAKEN OF MOVE NORTHEAST IN THE
UPPER MIDWEST TUESDAY. OTHER THAN A BRIEF INCREASE IN MID AND HIGH
CLOUDS TUESDAY...AND AN INCREASE IN SOUTH WINDS...THIS SYSTEM WILL
OFFER NO CHANCE OF MEASURABLE RAIN. IT IS HERE WHEN THE TWO MAIN
EXTEND MODELS DIVERGE. BOTH THE GFS AND ECMWF DEVELOP A LARGE
SYNOPTIC CUT OFF LOW IN THE ROCKIES BY WEDNESDAY. THE DEEP MOISTURE
RETURN ON BOTH MODELS INCREASES BY LATE THURSDAY...BUT THE ECMWF
BRINGS THIS ENERGY OUT OF THE SOUTHWEST IN ONE LARGE LOW...WELL TO
THE NORTH...VS THE GFS BRINGING ENERGY OUT IN TWO WAVES. THUS...IT
IS FASTER INITIALLY...AS IT BRINGS THE FRONT TO EASTERN IOWA BY
THURSDAY NIGHT...BUT AS ANOTHER WAVE LIFTS OUT OF THE ROCKIES
FRIDAY...MOISTURE CONVERGES ALONG THE BOUNDARY NEARBY TO PRODUCE A
SIGNIFICANT RAIN EVENT. THE ECMWF AND ITS SINGLE QUICK COLD FROPA
OFFERS VERY LITTLE THREAT OF RAIN. SO...WE ARE LEFT WITH A BLENDED
MODEL OUTPUT OF CHANCE POPS ON DAY 7. BOTH THE GFS AND ECMWF HAVE
BEEN CONSISTENT IN THESE SCENARIOS...AND BOTH APPEAR POSSIBLE.
THUS...TIME WILL TELL AS TO WHICH ENERGY DISTRIBUTION WILL BE
CORRECT.
ERVIN
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1245 PM CDT SAT SEP 21 2013
SCT-BKN028 TIL 21Z/21 AT KDBQ. ELSEWHERE ONLY SCT030-040 THIS AFTERNOON.
SKC TONIGHT AND SUNDAY AS HIGH PRESSURE BUILDS INTO THE REGION
FROM THE PLAINS. NORTHWEST WINDS 10 TO 15 KNOTS WITH OCNL GUSTS TO
NEAR 20 KNOTS THIS AFTERNOON. VARIABLE WINDS AROUND 5 KNOTS OR
LESS TONIGHT THEN SOUTHEAST WINDS LESS THAN 10 KNOTS SUNDAY.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...HAASE
SYNOPSIS...DC
SHORT TERM...DC
LONG TERM...ERVIN
AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1051 AM CDT SAT SEP 21 2013
.UPDATE...
ISSUED AT 1050 AM CDT SAT SEP 21 2013
PLEASANT FALL-LIKE DAY IN PROGRESS WITH CURRENT TEMPERATURES IN
THE MID 50S TO LOWER 60S. THESE READINGS APPEAR ON TARGET FOR
AFTERNOON HIGHS IN THE MID 60S TO LOWER 70S.
I AM WATCHING AN AREA OF STRATUS ACROSS MUCH OF WI AND EASTERN MN
WHERE THE LOW LEVELS ARE QUITE MOIST. THESE CLOUDS ARE SPREADING
SOUTHWARD BUT ALSO WILL BE RUNNING INTO DRIER AIR. OUR NW IL
COUNTIES LOOK VULNERABLE TO HAVING AT LEAST PARTLY SUNNY SKIES AND
HAVE INCREASED THE SKY GRIDS FOR THAT AREA. ELSEWHERE SCATTERED
CUMULUS/STRATOCUMULUS EXPECTED.
&&
.SYNOPSIS...
ISSUED AT 302 AM CDT SAT SEP 21 2013
FRIDAYS COLD FRONT STRETCHED FROM THE JAMES BAY SOUTHWARD TO KDTW TO
KDAY TO KMKL WITH SURFACE HIGH PRESSURE STRETCHING FROM SOUTHERN MANITOBA
SOUTHWARD TO THE TEXAS PANHANDLE. COOL...DRY AIR CONTINUED TO DROP
SOUTHWARD INTO THE UPPER MIDWEST FROM SOUTHERN CANADA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 302 AM CDT SAT SEP 21 2013
THE 500 HPA TROUGH AXIS HAS SHIFTED EASTWARD INTO CENTRAL ILLINOIS
AND WISCONSIN THIS MORNING WITH NORTHWEST FLOW ALOFT ACROSS THE
REGION. STRATUS WAS UPSTREAM OF THE REGION ACROSS EASTERN NORTH
DAKOTA AND WESTERN MINNESOTA. THIS AREA OF CLOUDS IS REPRESENTED
WELL BY 850 HPA RH. THE 00 UTC GFS AND ECMWF BOTH DEPICT THIS AREA
OF CLOUDS DISSIPATING OR GRAZING THE CORNER OF NORTHWEST ILLINOIS
LATER THIS MORNING WHILE THE RAP DEPICTS THE MOISTURE
OVERSPREADING THE REGION. THE RAP HAS TOO MUCH MOISTURE IN THE LOW
LEVELS AND WILL THUS KEEP CLOUD COVER DOWN ACROSS THE REGION THIS
MORNING. OTHERWISE HIGH PRESSURE WILL SLOW BUILD SOUTHWARD ACROSS
THE REGION DURING THE DAY ON SATURDAY. SKIES WILL BE MOSTLY SUNNY
WITH A FEW CU DEVELOPING. A PLEASANT DAY WITH HIGH TEMPERATURES
FROM THE MID 60S ALONG HIGHWAY 20 TO AROUND 70 ACROSS SOUTHEAST
IOWA AND NORTHWEST MISSOURI WHICH IS 10 DEGREES BELOW NORMAL FOR
MID SEPTEMBER.
HIGH PRESSURE WILL BE SITTING OVER THE REGION SATURDAY NIGHT INTO
SUNDAY MORNING WITH CLEAR SKIES AND STRONG RADIATIONAL COOLING. KEPT
LOW TEMPERATURES FOR SUNDAY MORNING THE SAME AS PREVIOUS SHIFTS. A
CHILLY MORNING ON SUNDAY WITH TEMPERATURES REMAINING BELOW NORMAL.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 302 AM CDT SAT SEP 21 2013
A CONSISTENTLY PLEASANT FALL WEATHER FORECAST IS IN STORE FOR SUNDAY
THROUGH THURSDAY...AS DRY WEATHER DOMINATES THE MIDWEST WEATHER.
THIS WILL INITIALLY BE THROUGH A COOL GREAT LAKES HIGH
PRESSURE...ONE THAT IS BUILDING IN TODAY. THE RESULTING WEATHER
ASSOCIATED WITH THIS HIGH WILL BE SEVERAL DAYS OF LIGHT EASTERLY
FLOW AT LOW LEVELS...AND VERY LARGE DIURNAL DAILY TRENDS. GUIDANCE
CONTINUES TO BE COOLING IN THE PAST FEW DAYS FOR SUNDAY THROUGH
TUESDAY...AND WE WILL CONTINUE TO FORECAST NEAR THE COOLER SIDE OF
OVERNIGHT LOWS...AND NEAR THE MEAN OF GUIDANCE HIGHS. THIS RESULTS
IN LOWS MAINLY IN THE LOWER 40S EAST TO UPPER 40S WEST SUNDAY
NIGHT...AND UPPER 40S/LOW 50S MONDAY NIGHT. SUNDAY THROUGH
TUESDAY...HIGHS WILL GRADUALLY INCREASE FROM THE LOWER 70S...TO MID
70S. IN ALL...VERY PLEASANT WEATHER.
A MOISTURE STARVED UPPER LOW WILL WEAKEN OF MOVE NORTHEAST IN THE
UPPER MIDWEST TUESDAY. OTHER THAN A BRIEF INCREASE IN MID AND HIGH
CLOUDS TUESDAY...AND AN INCREASE IN SOUTH WINDS...THIS SYSTEM WILL
OFFER NO CHANCE OF MEASURABLE RAIN. IT IS HERE WHEN THE TWO MAIN
EXTEND MODELS DIVERGE. BOTH THE GFS AND ECMWF DEVELOP A LARGE
SYNOPTIC CUT OFF LOW IN THE ROCKIES BY WEDNESDAY. THE DEEP MOISTURE
RETURN ON BOTH MODELS INCREASES BY LATE THURSDAY...BUT THE ECMWF
BRINGS THIS ENERGY OUT OF THE SOUTHWEST IN ONE LARGE LOW...WELL TO
THE NORTH...VS THE GFS BRINGING ENERGY OUT IN TWO WAVES. THUS...IT
IS FASTER INITIALLY...AS IT BRINGS THE FRONT TO EASTERN IOWA BY
THURSDAY NIGHT...BUT AS ANOTHER WAVE LIFTS OUT OF THE ROCKIES
FRIDAY...MOISTURE CONVERGES ALONG THE BOUNDARY NEARBY TO PRODUCE A
SIGNIFICANT RAIN EVENT. THE ECMWF AND ITS SINGLE QUICK COLD FROPA
OFFERS VERY LITTLE THREAT OF RAIN. SO...WE ARE LEFT WITH A BLENDED
MODEL OUTPUT OF CHANCE POPS ON DAY 7. BOTH THE GFS AND ECMWF HAVE
BEEN CONSISTENT IN THESE SCENARIOS...AND BOTH APPEAR POSSIBLE.
THUS...TIME WILL TELL AS TO WHICH ENERGY DISTRIBUTION WILL BE
CORRECT.
ERVIN
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 624 AM CDT SAT SEP 21 2013
HIGH PRESSURE WILL MOVE EASTWARD THROUGH THE DAY ON SATURDAY
BRINGING VFR CONDITIONS TO ALL TAF SITES THROUGH THE PERIOD.
HOWEVER...AN AREA OF MVFR STRATUS CURRENTLY SITS ACROSS NORTHERN
MINNNESOTA AND WISCONSIN BUT CONFIDENCE IS LOW THAT IT WILL EFFECT
AREA TAF SITES. EXPECT A FEW TO SCT CU TO DEVELOP LATE THIS
MORING AND CONTINUE INTO THE EARLY AFTERNOON WITH THE BASES AOA
4KFT. NORTH TO NORTHWEST WINDS WILL INCREASE TO 10 TO 15 KNOTS BY
EARLY AFTERNOON AND DIMINISH BY EARLY EVENING. WINDS WILL DROP TO
5 KNOTS OR LESS AND SWING AROUND TO AN EASTERLY DIRECTION AFTER
00 UTC ON SUNDAY.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...HAASE
SYNOPSIS...DC
SHORT TERM...DC
LONG TERM...ERVIN
AVIATION...DC
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
635 AM CDT SAT SEP 21 2013
.SYNOPSIS...
ISSUED AT 302 AM CDT SAT SEP 21 2013
FRIDAYS COLD FRONT STRETCHED FROM THE JAMES BAY SOUTHWARD TO KDTW TO
KDAY TO KMKL WITH SURFACE HIGH PRESSURE STRETCHING FROM SOUTHERN MANITOBA
SOUTHWARD TO THE TEXAS PANHANDLE. COOL...DRY AIR CONTINUED TO DROP
SOUTHWARD INTO THE UPPER MIDWEST FROM SOUTHERN CANADA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 302 AM CDT SAT SEP 21 2013
THE 500 HPA TROUGH AXIS HAS SHIFTED EASTWARD INTO CENTRAL ILLINOIS
AND WISCONSIN THIS MORNING WITH NORTHWEST FLOW ALOFT ACROSS THE
REGION. STRATUS WAS UPSTREAM OF THE REGION ACROSS EASTERN NORTH
DAKOTA AND WESTERN MINNESOTA. THIS AREA OF CLOUDS IS REPRESENTED
WELL BY 850 HPA RH. THE 00 UTC GFS AND ECMWF BOTH DEPICT THIS AREA
OF CLOUDS DISSIPATING OR GRAZING THE CORNER OF NORTHWEST ILLINOIS
LATER THIS MORNING WHILE THE RAP DEPICTS THE MOISTURE
OVERSPREADING THE REGION. THE RAP HAS TOO MUCH MOISTURE IN THE LOW
LEVELS AND WILL THUS KEEP CLOUD COVER DOWN ACROSS THE REGION THIS
MORNING. OTHERWISE HIGH PRESSURE WILL SLOW BUILD SOUTHWARD ACROSS
THE REGION DURING THE DAY ON SATURDAY. SKIES WILL BE MOSTLY SUNNY
WITH A FEW CU DEVELOPING. A PLEASANT DAY WITH HIGH TEMPERATURES
FROM THE MID 60S ALONG HIGHWAY 20 TO AROUND 70 ACROSS SOUTHEAST
IOWA AND NORTHWEST MISSOURI WHICH IS 10 DEGREES BELOW NORMAL FOR
MID SEPTEMBER.
HIGH PRESSURE WILL BE SITTING OVER THE REGION SATURDAY NIGHT INTO
SUNDAY MORNING WITH CLEAR SKIES AND STRONG RADIATIONAL COOLING. KEPT
LOW TEMPERATURES FOR SUNDAY MORNING THE SAME AS PREVIOUS SHIFTS. A
CHILLY MORNING ON SUNDAY WITH TEMPERATURES REMAINING BELOW NORMAL.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 302 AM CDT SAT SEP 21 2013
A CONSISTENTLY PLEASANT FALL WEATHER FORECAST IS IN STORE FOR SUNDAY
THROUGH THURSDAY...AS DRY WEATHER DOMINATES THE MIDWEST WEATHER.
THIS WILL INITIALLY BE THROUGH A COOL GREAT LAKES HIGH
PRESSURE...ONE THAT IS BUILDING IN TODAY. THE RESULTING WEATHER
ASSOCIATED WITH THIS HIGH WILL BE SEVERAL DAYS OF LIGHT EASTERLY
FLOW AT LOW LEVELS...AND VERY LARGE DIURNAL DAILY TRENDS. GUIDANCE
CONTINUES TO BE COOLING IN THE PAST FEW DAYS FOR SUNDAY THROUGH
TUESDAY...AND WE WILL CONTINUE TO FORECAST NEAR THE COOLER SIDE OF
OVERNIGHT LOWS...AND NEAR THE MEAN OF GUIDANCE HIGHS. THIS RESULTS
IN LOWS MAINLY IN THE LOWER 40S EAST TO UPPER 40S WEST SUNDAY
NIGHT...AND UPPER 40S/LOW 50S MONDAY NIGHT. SUNDAY THROUGH
TUESDAY...HIGHS WILL GRADUALLY INCREASE FROM THE LOWER 70S...TO MID
70S. IN ALL...VERY PLEASANT WEATHER.
A MOISTURE STARVED UPPER LOW WILL WEAKEN OF MOVE NORTHEAST IN THE
UPPER MIDWEST TUESDAY. OTHER THAN A BRIEF INCREASE IN MID AND HIGH
CLOUDS TUESDAY...AND AN INCREASE IN SOUTH WINDS...THIS SYSTEM WILL
OFFER NO CHANCE OF MEASURABLE RAIN. IT IS HERE WHEN THE TWO MAIN
EXTEND MODELS DIVERGE. BOTH THE GFS AND ECMWF DEVELOP A LARGE
SYNOPTIC CUT OFF LOW IN THE ROCKIES BY WEDNESDAY. THE DEEP MOISTURE
RETURN ON BOTH MODELS INCREASES BY LATE THURSDAY...BUT THE ECMWF
BRINGS THIS ENERGY OUT OF THE SOUTHWEST IN ONE LARGE LOW...WELL TO
THE NORTH...VS THE GFS BRINGING ENERGY OUT IN TWO WAVES. THUS...IT
IS FASTER INITIALLY...AS IT BRINGS THE FRONT TO EASTERN IOWA BY
THURSDAY NIGHT...BUT AS ANOTHER WAVE LIFTS OUT OF THE ROCKIES
FRIDAY...MOISTURE CONVERGES ALONG THE BOUNDARY NEARBY TO PRODUCE A
SIGNIFICANT RAIN EVENT. THE ECMWF AND ITS SINGLE QUICK COLD FROPA
OFFERS VERY LITTLE THREAT OF RAIN. SO...WE ARE LEFT WITH A BLENDED
MODEL OUTPUT OF CHANCE POPS ON DAY 7. BOTH THE GFS AND ECMWF HAVE
BEEN CONSISTENT IN THESE SCENARIOS...AND BOTH APPEAR POSSIBLE.
THUS...TIME WILL TELL AS TO WHICH ENERGY DISTRIBUTION WILL BE
CORRECT.
ERVIN
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 624 AM CDT SAT SEP 21 2013
HIGH PRESSURE WILL MOVE EASTWARD THROUGH THE DAY ON SATURDAY
BRINGING VFR CONDITIONS TO ALL TAF SITES THROUGH THE PERIOD.
HOWEVER...AN AREA OF MVFR STRATUS CURRENTLY SITS ACROSS NORTHERN
MINNNESOTA AND WISCONSIN BUT CONFIDENCE IS LOW THAT IT WILL EFFECT
AREA TAF SITES. EXPECT A FEW TO SCT CU TO DEVELOP LATE THIS
MORING AND CONTINUE INTO THE EARLY AFTERNOON WITH THE BASES AOA
4KFT. NORTH TO NORTHWEST WINDS WILL INCREASE TO 10 TO 15 KNOTS BY
EARLY AFTERNOON AND DIMINISH BY EARLY EVENING. WINDS WILL DROP TO
5 KNOTS OR LESS AND SWING AROUND TO AN EASTERLY DIRECTION AFTER
00 UTC ON SUNDAY.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...DC
SHORT TERM...DC
LONG TERM...ERVIN
AVIATION...DC
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
309 AM CDT SAT SEP 21 2013
.SYNOPSIS...
ISSUED AT 302 AM CDT SAT SEP 21 2013
FRIDAYS COLD FRONT STRETCHED FROM THE JAMES BAY SOUTHWARD TO KDTW TO
KDAY TO KMKL WITH SURFACE HIGH PRESSURE STRETCHING FROM SOUTHERN MANITOBA
SOUTHWARD TO THE TEXAS PANHANDLE. COOL...DRY AIR CONTINUED TO DROP
SOUTHWARD INTO THE UPPER MIDWEST FROM SOUTHERN CANADA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 302 AM CDT SAT SEP 21 2013
THE 500 HPA TROUGH AXIS HAS SHIFTED EASTWARD INTO CENTRAL ILLINOIS
AND WISCONSIN THIS MORNING WITH NORTHWEST FLOW ALOFT ACROSS THE
REGION. STRATUS WAS UPSTREAM OF THE REGION ACROSS EASTERN NORTH
DAKOTA AND WESTERN MINNESOTA. THIS AREA OF CLOUDS IS REPRESENTED
WELL BY 850 HPA RH. THE 00 UTC GFS AND ECMWF BOTH DEPICT THIS AREA
OF CLOUDS DISSIPATING OR GRAZING THE CORNER OF NORTHWEST ILLINOIS
LATER THIS MORNING WHILE THE RAP DEPICTS THE MOISTURE
OVERSPREADING THE REGION. THE RAP HAS TOO MUCH MOISTURE IN THE LOW
LEVELS AND WILL THUS KEEP CLOUD COVER DOWN ACROSS THE REGION THIS
MORNING. OTHERWISE HIGH PRESSURE WILL SLOW BUILD SOUTHWARD ACROSS
THE REGION DURING THE DAY ON SATURDAY. SKIES WILL BE MOSTLY SUNNY
WITH A FEW CU DEVELOPING. A PLEASANT DAY WITH HIGH TEMPERATURES
FROM THE MID 60S ALONG HIGHWAY 20 TO AROUND 70 ACROSS SOUTHEAST
IOWA AND NORTHWEST MISSOURI WHICH IS 10 DEGREES BELOW NORMAL FOR
MID SEPTEMBER.
HIGH PRESSURE WILL BE SITTING OVER THE REGION SATURDAY NIGHT INTO
SUNDAY MORNING WITH CLEAR SKIES AND STRONG RADIATIONAL COOLING. KEPT
LOW TEMPERATURES FOR SUNDAY MORNING THE SAME AS PREVIOUS SHIFTS. A
CHILLY MORNING ON SUNDAY WITH TEMPERATURES REMAINING BELOW NORMAL.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 302 AM CDT SAT SEP 21 2013
A CONSISTENTLY PLEASANT FALL WEATHER FORECAST IS IN STORE FOR SUNDAY
THROUGH THURSDAY...AS DRY WEATHER DOMINATES THE MIDWEST WEATHER.
THIS WILL INITIALLY BE THROUGH A COOL GREAT LAKES HIGH
PRESSURE...ONE THAT IS BUILDING IN TODAY. THE RESULTING WEATHER
ASSOCIATED WITH THIS HIGH WILL BE SEVERAL DAYS OF LIGHT EASTERLY
FLOW AT LOW LEVELS...AND VERY LARGE DIURNAL DAILY TRENDS. GUIDANCE
CONTINUES TO BE COOLING IN THE PAST FEW DAYS FOR SUNDAY THROUGH
TUESDAY...AND WE WILL CONTINUE TO FORECAST NEAR THE COOLER SIDE OF
OVERNIGHT LOWS...AND NEAR THE MEAN OF GUIDANCE HIGHS. THIS RESULTS
IN LOWS MAINLY IN THE LOWER 40S EAST TO UPPER 40S WEST SUNDAY
NIGHT...AND UPPER 40S/LOW 50S MONDAY NIGHT. SUNDAY THROUGH
TUESDAY...HIGHS WILL GRADUALLY INCREASE FROM THE LOWER 70S...TO MID
70S. IN ALL...VERY PLEASANT WEATHER.
A MOISTURE STARVED UPPER LOW WILL WEAKEN OF MOVE NORTHEAST IN THE
UPPER MIDWEST TUESDAY. OTHER THAN A BRIEF INCREASE IN MID AND HIGH
CLOUDS TUESDAY...AND AN INCREASE IN SOUTH WINDS...THIS SYSTEM WILL
OFFER NO CHANCE OF MEASURABLE RAIN. IT IS HERE WHEN THE TWO MAIN
EXTEND MODELS DIVERGE. BOTH THE GFS AND ECMWF DEVELOP A LARGE
SYNOPTIC CUT OFF LOW IN THE ROCKIES BY WEDNESDAY. THE DEEP MOISTURE
RETURN ON BOTH MODELS INCREASES BY LATE THURSDAY...BUT THE ECMWF
BRINGS THIS ENERGY OUT OF THE SOUTHWEST IN ONE LARGE LOW...WELL TO
THE NORTH...VS THE GFS BRINGING ENERGY OUT IN TWO WAVES. THUS...IT
IS FASTER INITIALLY...AS IT BRINGS THE FRONT TO EASTERN IOWA BY
THURSDAY NIGHT...BUT AS ANOTHER WAVE LIFTS OUT OF THE ROCKIES
FRIDAY...MOISTURE CONVERGES ALONG THE BOUNDARY NEARBY TO PRODUCE A
SIGNIFICANT RAIN EVENT. THE ECMWF AND ITS SINGLE QUICK COLD FROPA
OFFERS VERY LITTLE THREAT OF RAIN. SO...WE ARE LEFT WITH A BLENDED
MODEL OUTPUT OF CHANCE POPS ON DAY 7. BOTH THE GFS AND ECMWF HAVE
BEEN CONSISTENT IN THESE SCENARIOS...AND BOTH APPEAR POSSIBLE.
THUS...TIME WILL TELL AS TO WHICH ENERGY DISTRIBUTION WILL BE
CORRECT.
ERVIN
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1136 PM CDT FRI SEP 20 2013
HIGH PRESSURE OVER THE PLAINS WILL MOVE EAST INTO THE MISSISSIPPI
VALLEY BY SATURDAY AFTERNOON. VFR CONDITIONS WILL REMAIN OVER THE
AREA WITH SCATTERED CLOUDS BASED AROUND 4KFT REMAINING OVER THE
AREA THE REST OF TONIGHT AND SATURDAY.
DLF
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...DC
SHORT TERM...DC
LONG TERM...ERVIN
AVIATION...DLF
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1100 PM CDT Fri Sep 20 2013
.UPDATE...
ISSUED AT 1056 PM CDT FRI SEP 20 2013
UPDATED AVIATION SECTION FOR 06Z TAF ISSUANCE.
UPDATE A tight sfc wave (shown especially in NAM12 data) was moving newd
through the srn Pennyrile region of wrn ky this evening, offering a
potential source of lift. To the nw of this feature, light sfc winds
had already turned to the north ahead of a cold front moving through
the nwrn half of the PAH forecast area. Working against the feature
is the stabilizing atmosphere. What is left of any lower trop
instability will quickly exit the ern fringes of the region shortly.
Thus, there is no mention of tstms or locally heavy rain in the
forecast beyond 03z. The forward progress of the front seemed to be
on track at this time, and all pcpn should be out of the region by
12z.
&&
.SHORT TERM /Tonight through Sunday night/...
ISSUED AT 240 PM CDT FRI SEP 20 2013
Forecast seems to be panning out fairly well. Widespread rain has
overspread most of the forecast area this afternoon. Aside from a
convective cluster over western Kentucky...deep convection has been
largely absent. Instability has been limited by lack of solar
heating due to thickening mid/high clouds.
The qpf forecast seems to be on track...with the lowest amounts in
southern IL and southeast MO. Heavy rainfall is still occurring and
expected in western KY and possibly southwest IN. Due to dry
ground...any issues should be limited to urban and poor drainage
areas. Rainfall rates will continue to be locally over one inch per
hour in convection.
The latest HRRR is fairly close to the model consensus. The back
edge of the rain will move across the kpah/kevv areas in the 03z to
06z time frame. The precip will end in the khop area by 12z.
Clearing will occur on Saturday morning...with nothing more than
some scattered cu in the afternoon. 850 mb temps are forecast to
fall to around 10...which supports mos guidance highs in the mid
70s.
Little change in 850 mb temps or moisture profiles is forecast
through Sunday night. This will keep clear and cool conditions in
place...with daytime highs in the 70s and overnight lows in the mid
40s to near 50. North to northeast low level winds will slowly
decrease as high pressure builds overhead.
.LONG TERM /Monday through Friday/...
ISSUED AT 240 PM CDT FRI SEP 20 2013
As we head into next week, it now appears as though the upper level
high over the eastern U.S. will shift farther east as short wave
energy moves east into the MS River Valley. It still appears as
though our region may stay in between the two main branches of
energy, one passing to our north and the other just to our
south/east. If current trends continue, later forecasts may need to
mention a chc of rain in srn portions of west KY on Tuesday/Tue
night.
Thereafter...the upper high over the southeast U.S. will begin to
flex its muscle, and build north into the Ohio Valley. Thus... we
should see less cloud cover and warming temps as we head into the
Wed/Thu/Fri time frame. Most locations will likely be back into the
middle 80s by Wednesday afternoon. Humidity levels should stay
fairly comfortable until late in the week, when southerly flow will
develop ahead of an approaching cold front.
&&
.AVIATION...
ISSUED AT 1056 PM CDT FRI SEP 20 2013
CIGS VARYING FROM IFR TO VFR WILL CONTINUE FOR A FEW MORE HOURS.
PCPN WILL BE SLOW TO DEPART AS WELL. BUT EVENTUALLY LATE TONIGHT
BOTH WILL CEDE TO CLEARING SKIES AS POST FRONTAL DRIER/COOLER AIR
WORKS IN. SOME LIGHT NLYS SHOULD PICK UP AND PRECLUDE FOG...BUT
THIS SHOULD BE MONITORED CLOSELY AS MOS SUGGESTS OTHERWISE. TMRW
SHOULD BE NIL WX DAY WITH VFR THRU REMAINDER OF FORECAST.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CARIBOU ME
102 PM EDT SAT SEP 21 2013
.SYNOPSIS...
A SOUTHERLY FLOW WILL BRING WARMER AND INCREASINGLY MOIST AIR TO
THE REGION TODAY. A STRONG COLD FRONT WILL APPROACH THE STATE TONIGHT
AND IS EXPECTED TO MOVE THROUGH THE FORECAST AREA ON SUNDAY.&&
.NEAR TERM /THROUGH TONIGHT/...
1 PM UPDATE: MADE SOME MINOR CHANGES TO TEMPERATURE, WIND, SKY
GRIDS FOR THIS AFTERNOON BASED ON CURRENT CONDITIONS. ALSO MADE
SOME CHANGES TO POP, QPF GRIDS FOR LATER TONIGHT BASED ON THE
LATEST TRENDS WITH RADAR, SATELLITE AND FORECAST GUIDANCE. MAIN
CHANGE WAS TO BEEF UP QPF FOR THE OVERNIGHT PERIOD ALONG THE
WESTERN BORDER OF THE CWA.
PREVIOUS DISCUSSION... CHALLENGE THIS TERM WILL BE
CLOUDS AND DRIZZLE TODAY AND TIMING OF RAIN AND INCREASING WINDS
TONIGHT.
LATEST IR SATL 11.3-3.9 MICRON IMAGERY SHOWING LOW CLOUDS OVER THE
EASTERN 1/2 OF THE CWA THANKS IN PART TO THE SE FLOW. LOW CLOUDS
EXTEND FROM KFVE ALL THE DOWN TO THE KBHB REGION. FURTHER W, HIGH
CLOUDS MOVING ACROSS THE REGION. SOME DRIZZLE OCCURRING MAINLY
ACROSS THE E AND NE SECTIONS PER THE METARS AND WEBCAMS. THE NAM12
AND HRRR HANDLING THE CLOUDS WELL PER THE 06Z ANALYSIS. LATEST
RADAR TRENDS SHOWED DRIZZLE BECOMING MORE SPOTTY AS THE WINDS
BEGIN TO SHIFT TO A MORE S DIRECTION AND THIS PICKED UP WELL BY
THE 00Z NAM AS WELL. ACROSS THE DOWNEAST AND COAST, AREAS OF DRIZZLE
AND FOG THIS MORNING. CONDITIONS ARE EXPECTED TO IMPROVE LATER
THIS MORNING AS THE FLOW BECOMES MORE SLY AND LLVLS DRY OUT.
SUNSHINE RETURNING LATER ON WILL ALLOW FOR TEMPERATURES TO WARM
INTO THE 70S AWAY FROM THE DOWNEAST AND COAST AS S WIND WILL KEEP
TEMPERATURES DOWN ACROSS THE DOWNEAST AND COAST. THE LATEST NAM/RUC
SOUNDINGS POINT TO THIS TAKING PLACE. S WINDS PICKING UP TODAY AT
15 TO 20 MPH WITH HIGHER GUSTS AS SHOWN BY THE 00Z NAM AND 04Z HRRR.
THE TREND CONTINUES TO BE THAT RAIN WILL BE HELD OFF UNTIL LATER
TONIGHT AS A STRONG COLD FRONT BEGINS TO APCH FROM THE W. THE 00Z
RUNS OF THE NAM AND GFS SHOW AN INITIAL BATCH OF SHOWERS/RAIN OUT
AHEAD OF THE FRONT ACROSS THE W AND SW AREAS AND IN RESPONSE TO
AN UPPER LEVEL DISTURBANCE MOVING ACROSS THIS REGION. BUFKIT
PROFILES ALSO SHOW THE POTENTIAL FOR DRIZZLE TO SET UP AGAIN LATER
TONIGHT W/THE INCREASINGLY MOIST S FLOW. SOUNDINGS SHOW LLVLS
BELOW 900MBS MOISTENING W/DRY AIR ABOVE THIS LEVEL INDICATIVE OF
THE POTENTIAL FOR DRIZZLE. ADDED PERIODS OF DRIZZLE STARTING LATER
THIS EVENING AND THEN TRANSITIONING TO RAIN MOVES IN BY SUNDAY
MORNING. THE STEADIEST RAINFALL WILL BE W OF A CARIBOU-BANGOR
LINE. S WINDS WILL BE ON THE INCREASE AS WELL AS SHOWN BY THE
LATEST NAM AND GFS. KEPT WINDS 10 TO 20 MPH TONIGHT W/GUSTS TO 25
MPH.
.SHORT TERM /SUNDAY THROUGH MONDAY/...
A COLD FRONT WILL CROSS THE REGION DURING SUNDAY. THE FRONT WILL
BE ACCOMPANIED BY A PERIOD OF STEADIER RAIN LATER SUNDAY MORNING
AND SUNDAY AFTERNOON. RAINFALL AMOUNTS DURING SUNDAY ARE EXPECTED
TO RANGE FROM THREE-QUARTERS TO ONE INCH AS A LOW LEVEL JET IN THE
925-850 MB LEVEL TRAVERSES THE REGION IN ADVANCE OF THE FRONT. THE
LOW LEVEL JET WILL ALSO RESULT IN GUSTY SOUTH WINDS IN ADVANCE OF
THE FRONT. HAVE INCLUDED THE MENTION OF ISOLATED THUNDER WITH SOME
ELEVATED INSTABILITY AHEAD OF THE FRONT AND THERE CURRENTLY IS
SOME LIGHTNING SHOWING UP IN ADVANCE OF THE BOUNDARY ATTM. THE
FRONT WILL MOVE EAST OF THE DOWNEAST COAST LATER SUNDAY AFTERNOON
ENDING THE STEADIEST RAINFALL.
EXPECT PARTLY TO MOSTLY CLOUDY SKIES ACROSS NORTHERN AREAS SUNDAY
NIGHT AND MONDAY AS AN UPPER LEVEL LOW CROSSES THE REGION WITH
PARTLY CLOUDY SKIES DOWNEAST. MUCH COOLER AIR WILL FLOW IN BEHIND
THE FRONT SUNDAY NIGHT AND MONDAY. LOWS SUNDAY NIGHT WILL RANGE FROM
THE LOW TO MID 40S AND HIGHS ON MONDAY WILL RANGE FROM THE LOW TO
MID 50S NORTH AND MID TO UPPER 50S DOWNEAST.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
AN UPPER LOW WILL SLOWLY MOVE EAST OF THE MARITIMES THROUGH MID
WEEK. THIS WILL KEEP A MAINLY DRY AND CHILLY WEATHER PATTERN
ACROSS THE REGION THROUGH MID WEEK.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
NEAR TERM: IFR ATTM ACROSS ALL THE TERMINALS W/FOG A NUISANCE AS
VSBYS ARE <1 MILE AT KBGR AND KBHB. CONDITIONS ARE EXPECTED TO
IMPROVE LATER THIS MORNING TO MVFR AND THEN VFR. EXPECTING
CONDITIONS TO DROP BACK TO MVFR LATER IN THE EVENING AND THEN DOWN
TO IFR BY EARLY SUNDAY MORNING.
SHORT TERM:IFR/MVFR CONDITIONS CAN BE EXPECTED ON SUNDAY IN RAIN IN
ADVANCE OF AN APPROACHING COLD FRONT. GENERALLY VFR IS EXPECTED
SUNDAY NIGHT AND BEYOND EXCEPT SOME MVFR CIGS ARE IS POSSIBLE AT
TIMES MAINLY ACROSS NORTHERN AREAS.
&&
.MARINE...
NEAR TERM: FOG WILL LEAD TO NAVIGATIONAL PROBLEMS TODAY AS A SSE
WIND CONTINUES. DECIDED TO HOIST AN SCA FOR LATER TONIGHT INTO
SUNDAY AS WINDS ARE FCST TO INCREASE TO SUSTAINED SPEEDS OF 15 TO
20 KTS AND GUSTS TO 25 KTS. LATEST WNAWAVE COMING IN LINE ATTM PER
THE LATEST OBS SHOWING WAVE HEIGHTS OF 2 FT. DECIDED TO FOLLOW THE
DAY CREW`S LEAD OF INCREASING SEAS TO 4 TO 6 FT BY SUNDAY MORNING.
SHORT TERM: A SMALL CRAFT ADVISORY IS IN EFFECT FOR SUNDAY AS
WINDS/SEAS INCREASE IN ADVANCE OF THE APPROACHING COLD FRONT.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM TO 4 PM EDT SUNDAY FOR
ANZ050>052.
&&
$$
NEAR TERM...FITZSIMMONS/HEWITT
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...FITZSIMMONS/HEWITT/DUDA
MARINE...FITZSIMMONS/HEWITT/DUDA
AREA FORECAST DISCUSSION
NWS CARIBOU ME
935 AM EDT SAT SEP 21 2013
.SYNOPSIS...
A SOUTHERLY FLOW WILL BRING WARMER AND INCREASINGLY MOIST AIR TO
THE REGION TODAY. A STRONG COLD FRONT WILL APPROACH THE STATE TONIGHT
AND IS EXPECTED TO MOVE THROUGH THE FORECAST AREA ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
930 AM UPDATE: MADE SOME FAIRLY MINOR CHANGES TO SKY COVER,
TEMPERATURE, DEW POINT, AND WIND GRIDS FOR THIS MORNING INTO THE
EARLY AFTERNOON BASED ON CURRENT CURRENT CONDITIONS. ALSO REMOVED
PATCHY DRIZZLE FROM THE FORECAST FOR THIS MORNING AS THIS NO
LONGER LOOKS TO BE AN ISSUE. NO OTHER CHANGES AT THIS TIME.
PREVIOUS DISCUSSION... CHALLENGE THIS TERM WILL BE
CLOUDS AND DRIZZLE TODAY AND TIMING OF RAIN AND INCREASING WINDS
TONIGHT.
LATEST IR SATL 11.3-3.9 MICRON IMAGERY SHOWING LOW CLOUDS OVER THE
EASTERN 1/2 OF THE CWA THANKS IN PART TO THE SE FLOW. LOW CLOUDS
EXTEND FROM KFVE ALL THE DOWN TO THE KBHB REGION. FURTHER W, HIGH
CLOUDS MOVING ACROSS THE REGION. SOME DRIZZLE OCCURRING MAINLY
ACROSS THE E AND NE SECTIONS PER THE METARS AND WEBCAMS. THE NAM12
AND HRRR HANDLING THE CLOUDS WELL PER THE 06Z ANALYSIS. LATEST
RADAR TRENDS SHOWED DRIZZLE BECOMING MORE SPOTTY AS THE WINDS
BEGIN TO SHIFT TO A MORE S DIRECTION AND THIS PICKED UP WELL BY
THE 00Z NAM AS WELL. ACROSS THE DOWNEAST AND COAST, AREAS OF DRIZZLE
AND FOG THIS MORNING. CONDITIONS ARE EXPECTED TO IMPROVE LATER
THIS MORNING AS THE FLOW BECOMES MORE SLY AND LLVLS DRY OUT.
SUNSHINE RETURNING LATER ON WILL ALLOW FOR TEMPERATURES TO WARM
INTO THE 70S AWAY FROM THE DOWNEAST AND COAST AS S WIND WILL KEEP
TEMPERATURES DOWN ACROSS THE DOWNEAST AND COAST. THE LATEST NAM/RUC
SOUNDINGS POINT TO THIS TAKING PLACE. S WINDS PICKING UP TODAY AT
15 TO 20 MPH WITH HIGHER GUSTS AS SHOWN BY THE 00Z NAM AND 04Z HRRR.
THE TREND CONTINUES TO BE THAT RAIN WILL BE HELD OFF UNTIL LATER
TONIGHT AS A STRONG COLD FRONT BEGINS TO APCH FROM THE W. THE 00Z
RUNS OF THE NAM AND GFS SHOW AN INITIAL BATCH OF SHOWERS/RAIN OUT
AHEAD OF THE FRONT ACROSS THE W AND SW AREAS AND IN RESPONSE TO
AN UPPER LEVEL DISTURBANCE MOVING ACROSS THIS REGION. BUFKIT
PROFILES ALSO SHOW THE POTENTIAL FOR DRIZZLE TO SET UP AGAIN LATER
TONIGHT W/THE INCREASINGLY MOIST S FLOW. SOUNDINGS SHOW LLVLS
BELOW 900MBS MOISTENING W/DRY AIR ABOVE THIS LEVEL INDICATIVE OF
THE POTENTIAL FOR DRIZZLE. ADDED PERIODS OF DRIZZLE STARTING LATER
THIS EVENING AND THEN TRANSITIONING TO RAIN MOVES IN BY SUNDAY
MORNING. THE STEADIEST RAINFALL WILL BE W OF A CARIBOU-BANGOR
LINE. S WINDS WILL BE ON THE INCREASE AS WELL AS SHOWN BY THE
LATEST NAM AND GFS. KEPT WINDS 10 TO 20 MPH TONIGHT W/GUSTS TO 25
MPH.
.SHORT TERM /SUNDAY THROUGH MONDAY/...
A COLD FRONT WILL CROSS THE REGION DURING SUNDAY. THE FRONT WILL
BE ACCOMPANIED BY A PERIOD OF STEADIER RAIN LATER SUNDAY MORNING
AND SUNDAY AFTERNOON. RAINFALL AMOUNTS DURING SUNDAY ARE EXPECTED
TO RANGE FROM THREE-QUARTERS TO ONE INCH AS A LOW LEVEL JET IN THE
925-850 MB LEVEL TRAVERSES THE REGION IN ADVANCE OF THE FRONT. THE
LOW LEVEL JET WILL ALSO RESULT IN GUSTY SOUTH WINDS IN ADVANCE OF
THE FRONT. HAVE INCLUDED THE MENTION OF ISOLATED THUNDER WITH SOME
ELEVATED INSTABILITY AHEAD OF THE FRONT AND THERE CURRENTLY IS
SOME LIGHTNING SHOWING UP IN ADVANCE OF THE BOUNDARY ATTM. THE
FRONT WILL MOVE EAST OF THE DOWNEAST COAST LATER SUNDAY AFTERNOON
ENDING THE STEADIEST RAINFALL.
EXPECT PARTLY TO MOSTLY CLOUDY SKIES ACROSS NORTHERN AREAS SUNDAY
NIGHT AND MONDAY AS AN UPPER LEVEL LOW CROSSES THE REGION WITH
PARTLY CLOUDY SKIES DOWNEAST. MUCH COOLER AIR WILL FLOW IN BEHIND
THE FRONT SUNDAY NIGHT AND MONDAY. LOWS SUNDAY NIGHT WILL RANGE FROM
THE LOW TO MID 40S AND HIGHS ON MONDAY WILL RANGE FROM THE LOW TO
MID 50S NORTH AND MID TO UPPER 50S DOWNEAST.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
AN UPPER LOW WILL SLOWLY MOVE EAST OF THE MARITIMES THROUGH MID
WEEK. THIS WILL KEEP A MAINLY DRY AND CHILLY WEATHER PATTERN
ACROSS THE REGION THROUGH MID WEEK.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: IFR ATTM ACROSS ALL THE TERMINALS W/FOG A NUISANCE AS
VSBYS ARE <1 MILE AT KBGR AND KBHB. CONDITIONS ARE EXPECTED TO
IMPROVE LATER THIS MORNING TO MVFR AND THEN VFR. EXPECTING
CONDITIONS TO DROP BACK TO MVFR LATER IN THE EVENING AND THEN DOWN
TO IFR BY EARLY SUNDAY MORNING.
SHORT TERM:IFR/MVFR CONDITIONS CAN BE EXPECTED ON SUNDAY IN RAIN IN
ADVANCE OF AN APPROACHING COLD FRONT. GENERALLY VFR IS EXPECTED
SUNDAY NIGHT AND BEYOND EXCEPT SOME MVFR CIGS ARE IS POSSIBLE AT
TIMES MAINLY ACROSS NORTHERN AREAS.
&&
.MARINE...
NEAR TERM: FOG WILL LEAD TO NAVIGATIONAL PROBLEMS TODAY AS A SSE
WIND CONTINUES. DECIDED TO HOIST AN SCA FOR LATER TONIGHT INTO
SUNDAY AS WINDS ARE FCST TO INCREASE TO SUSTAINED SPEEDS OF 15 TO
20 KTS AND GUSTS TO 25 KTS. LATEST WNAWAVE COMING IN LINE ATTM PER
THE LATEST OBS SHOWING WAVE HEIGHTS OF 2 FT. DECIDED TO FOLLOW THE
DAY CREW`S LEAD OF INCREASING SEAS TO 4 TO 6 FT BY SUNDAY MORNING.
SHORT TERM: A SMALL CRAFT ADVISORY IS IN EFFECT FOR SUNDAY AS
WINDS/SEAS INCREASE IN ADVANCE OF THE APPROACHING COLD FRONT.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM TO 4 PM EDT SUNDAY FOR
ANZ050>052.
&&
$$
NEAR TERM...FITZSIMMONS/HEWITT
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...FITZSIMMONS/HEWITT/DUDA
MARINE...FITZSIMMONS/HEWITT/DUDA
AREA FORECAST DISCUSSION
NWS CARIBOU ME
649 AM EDT SAT SEP 21 2013
.SYNOPSIS...
A SOUTHERLY FLOW WILL BRING WARMER AND INCREASINGLY MOIST AIR TO
THE REGION TODAY. A STRONG COLD FRONT WILL APPROACH THE STATE TONIGHT
AND IS EXPECTED TO MOVE THROUGH THE FORECAST AREA ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
650 AM UPDATE: ADJUSTED THE SKY COVER TO CARRY LOW CLOUDS A BIT
LONGER AS EVIDENT FROM THE LATEST SATL IMAGERY SHOWING LOW CLOUDS
HANGING TOUGH AND EXPANDING A BIT BACK TO THE W COVER THE
PISCATAQUIS COUNTY REGION. EXTENDED FOG AND DRIZZLE FOR THE
DOWNEAST AND COAST THROUGH LATE MORNING.
PREVIOUS DISCUSSION...
CHALLENGE THIS TERM WILL BE CLOUDS AND DRIZZLE TODAY AND TIMING
OF RAIN AND INCREASING WINDS TONIGHT.
LATEST IR SATL 11.3-3.9 MICRON IMAGERY SHOWING LOW CLOUDS OVER THE
EASTERN 1/2 OF THE CWA THANKS IN PART TO THE SE FLOW. LOW CLOUDS
EXTEND FROM KFVE ALL THE DOWN TO THE KBHB REGION. FURTHER W, HIGH
CLOUDS MOVING ACROSS THE REGION. SOME DRIZZLE OCCURRING MAINLY
ACROSS THE E AND NE SECTIONS PER THE METARS AND WEBCAMS. THE NAM12
AND HRRR HANDLING THE CLOUDS WELL PER THE 06Z ANALYSIS. LATEST
RADAR TRENDS SHOWED DRIZZLE BECOMING MORE SPOTTY AS THE WINDS
BEGIN TO SHIFT TO A MORE S DIRECTION AND THIS PICKED UP WELL BY
THE 00Z NAM AS WELL. ACROSS THE DOWNEAST AND COAST, AREAS OF DRIZZLE
AND FOG THIS MORNING. CONDITIONS ARE EXPECTED TO IMPROVE LATER
THIS MORNING AS THE FLOW BECOMES MORE SLY AND LLVLS DRY OUT.
SUNSHINE RETURNING LATER ON WILL ALLOW FOR TEMPERATURES TO WARM
INTO THE 70S AWAY FROM THE DOWNEAST AND COAST AS S WIND WILL KEEP
TEMPERATURES DOWN ACROSS THE DOWNEAST AND COAST. THE LATEST NAM/RUC
SOUNDINGS POINT TO THIS TAKING PLACE. S WINDS PICKING UP TODAY AT
15 TO 20 MPH WITH HIGHER GUSTS AS SHOWN BY THE 00Z NAM AND 04Z HRRR.
THE TREND CONTINUES TO BE THAT RAIN WILL BE HELD OFF UNTIL LATER
TONIGHT AS A STRONG COLD FRONT BEGINS TO APCH FROM THE W. THE 00Z
RUNS OF THE NAM AND GFS SHOW AN INITIAL BATCH OF SHOWERS/RAIN OUT
AHEAD OF THE FRONT ACROSS THE W AND SW AREAS AND IN RESPONSE TO
AN UPPER LEVEL DISTURBANCE MOVING ACROSS THIS REGION. BUFKIT
PROFILES ALSO SHOW THE POTENTIAL FOR DRIZZLE TO SET UP AGAIN LATER
TONIGHT W/THE INCREASINGLY MOIST S FLOW. SOUNDINGS SHOW LLVLS
BELOW 900MBS MOISTENING W/DRY AIR ABOVE THIS LEVEL INDICATIVE OF
THE POTENTIAL FOR DRIZZLE. ADDED PERIODS OF DRIZZLE STARTING LATER
THIS EVENING AND THEN TRANSITIONING TO RAIN MOVES IN BY SUNDAY
MORNING. THE STEADIEST RAINFALL WILL BE W OF A CARIBOU-BANGOR
LINE. S WINDS WILL BE ON THE INCREASE AS WELL AS SHOWN BY THE
LATEST NAM AND GFS. KEPT WINDS 10 TO 20 MPH TONIGHT W/GUSTS TO 25
MPH.
.SHORT TERM /SUNDAY THROUGH MONDAY/...
A COLD FRONT WILL CROSS THE REGION DURING SUNDAY. THE FRONT WILL
BE ACCOMPANIED BY A PERIOD OF STEADIER RAIN LATER SUNDAY MORNING
AND SUNDAY AFTERNOON. RAINFALL AMOUNTS DURING SUNDAY ARE EXPECTED
TO RANGE FROM THREE-QUARTERS TO ONE INCH AS A LOW LEVEL JET IN THE
925-850 MB LEVEL TRAVERSES THE REGION IN ADVANCE OF THE FRONT. THE
LOW LEVEL JET WILL ALSO RESULT IN GUSTY SOUTH WINDS IN ADVANCE OF
THE FRONT. HAVE INCLUDED THE MENTION OF ISOLATED THUNDER WITH SOME
ELEVATED INSTABILITY AHEAD OF THE FRONT AND THERE CURRENTLY IS
SOME LIGHTNING SHOWING UP IN ADVANCE OF THE BOUNDARY ATTM. THE
FRONT WILL MOVE EAST OF THE DOWNEAST COAST LATER SUNDAY AFTERNOON
ENDING THE STEADIEST RAINFALL.
EXPECT PARTLY TO MOSTLY CLOUDY SKIES ACROSS NORTHERN AREAS SUNDAY
NIGHT AND MONDAY AS AN UPPER LEVEL LOW CROSSES THE REGION WITH
PARTLY CLOUDY SKIES DOWNEAST. MUCH COOLER AIR WILL FLOW IN BEHIND
THE FRONT SUNDAY NIGHT AND MONDAY. LOWS SUNDAY NIGHT WILL RANGE FROM
THE LOW TO MID 40S AND HIGHS ON MONDAY WILL RANGE FROM THE LOW TO
MID 50S NORTH AND MID TO UPPER 50S DOWNEAST.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AN UPPER LOW WILL SLOWLY MOVE EAST OF THE MARITIMES THROUGH MID
WEEK. THIS WILL KEEP A MAINLY DRY AND CHILLY WEATHER PATTERN
ACROSS THE REGION THROUGH MID WEEK.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: IFR ATTM ACROSS ALL THE TERMINALS W/FOG A NUISANCE AS
VSBYS ARE <1 MILE AT KBGR AND KBHB. CONDITIONS ARE EXPECTED TO
IMPROVE LATER THIS MORNING TO MVFR AND THEN VFR. EXPECTING
CONDITIONS TO DROP BACK TO MVFR LATER IN THE EVENING AND THEN DOWN
TO IFR BY EARLY SUNDAY MORNING.
SHORT TERM:IFR/MVFR CONDITIONS CAN BE EXPECTED ON SUNDAY IN RAIN IN
ADVANCE OF AN APPROACHING COLD FRONT. GENERALLY VFR IS EXPECTED
SUNDAY NIGHT AND BEYOND EXCEPT SOME MVFR CIGS ARE IS POSSIBLE AT
TIMES MAINLY ACROSS NORTHERN AREAS.
&&
.MARINE...
NEAR TERM: FOG WILL LEAD TO NAVIGATIONAL PROBLEMS TODAY AS A SSE
WIND CONTINUES. DECIDED TO HOIST AN SCA FOR LATER TONIGHT INTO
SUNDAY AS WINDS ARE FCST TO INCREASE TO SUSTAINED SPEEDS OF 15 TO
20 KTS AND GUSTS TO 25 KTS. LATEST WNAWAVE COMING IN LINE ATTM PER
THE LATEST OBS SHOWING WAVE HEIGHTS OF 2 FT. DECIDED TO FOLLOW THE
DAYCREW`S LEAD OF INCREASING SEAS TO 4 TO 6 FT BY SUNDAY MORNING.
SHORT TERM: A SMALL CRAFT ADVISORY IS IN EFFECT FOR SUNDAY AS
WINDS/SEAS INCREASE IN ADVANCE OF THE APPROACHING COLD FRONT.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM TO 4 PM EDT SUNDAY FOR
ANZ050>052.
&&
$$
NEAR TERM...HEWITT
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HEWITT/DUDA
MARINE...HEWITT/DUDA
AREA FORECAST DISCUSSION
NWS CARIBOU ME
509 AM EDT SAT SEP 21 2013
.SYNOPSIS...
A SOUTHERLY FLOW WILL BRING WARMER AND INCREASINGLY MOIST AIR TO
THE REGION TODAY. A STRONG COLD FRONT WILL APPROACH THE STATE TONIGHT
AND IS EXPECTED TO MOVE THROUGH THE FORECAST AREA ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
CHALLENGE THIS TERM WILL BE CLOUDS AND DRIZZLE TODAY AND TIMING OF
RAIN AND INCREASING WINDS TONIGHT.
LATEST IR SATL 11.3-3.9 MICRON IMAGERY SHOWING LOW CLOUDS OVER THE
EASTERN 1/2 OF THE CWA THANKS IN PART TO THE SE FLOW. LOW CLOUDS
EXTEND FROM KFVE ALL THE DOWN TO THE KBHB REGION. FURTHER W, HIGH
CLOUDS MOVING ACROSS THE REGION. SOME DRIZZLE OCCURRING MAINLY
ACROSS THE E AND NE SECTIONS PER THE METARS AND WEBCAMS. THE NAM12
AND HRRR HANDLING THE CLOUDS WELL PER THE 06Z ANALYSIS. LATEST
RADAR TRENDS SHOWED DRIZZLE BECOMING MORE SPOTTY AS THE WINDS
BEGIN TO SHIFT TO A MORE S DIRECTION AND THIS PICKED UP WELL BY
THE 00Z NAM AS WELL. ACROSS THE DOWNEAST AND COAST, AREAS OF DRIZZLE
AND FOG THIS MORNING. CONDITIONS ARE EXPECTED TO IMPROVE LATER
THIS MORNING AS THE FLOW BECOMES MORE SLY AND LLVLS DRY OUT.
SUNSHINE RETURNING LATER ON WILL ALLOW FOR TEMPERATURES TO WARM
INTO THE 70S AWAY FROM THE DOWNEAST AND COAST AS S WIND WILL KEEP
TEMPERATURES DOWN ACROSS THE DOWNEAST AND COAST. THE LATEST NAM/RUC
SOUNDINGS POINT TO THIS TAKING PLACE. S WINDS PICKING UP TODAY AT
15 TO 20 MPH WITH HIGHER GUSTS AS SHOWN BY THE 00Z NAM AND 04Z HRRR.
THE TREND CONTINUES TO BE THAT RAIN WILL BE HELD OFF UNTIL LATER
TONIGHT AS A STRONG COLD FRONT BEGINS TO APCH FROM THE W. THE 00Z
RUNS OF THE NAM AND GFS SHOW AN INITIAL BATCH OF SHOWERS/RAIN OUT
AHEAD OF THE FRONT ACROSS THE W AND SW AREAS AND IN RESPONSE TO
AN UPPER LEVEL DISTURBANCE MOVING ACROSS THIS REGION. BUFKIT
PROFILES ALSO SHOW THE POTENTIAL FOR DRIZZLE TO SET UP AGAIN LATER
TONIGHT W/THE INCREASINGLY MOIST S FLOW. SOUNDINGS SHOW LLVLS
BELOW 900MBS MOISTENING W/DRY AIR ABOVE THIS LEVEL INDICATIVE OF
THE POTENTIAL FOR DRIZZLE. ADDED PERIODS OF DRIZZLE STARTING LATER
THIS EVENING AND THEN TRANSITIONING TO RAIN MOVES IN BY SUNDAY
MORNING. THE STEADIEST RAINFALL WILL BE W OF A CARIBOU-BANGOR
LINE. S WINDS WILL BE ON THE INCREASE AS WELL AS SHOWN BY THE
LATEST NAM AND GFS. KEPT WINDS 10 TO 20 MPH TONIGHT W/GUSTS TO 25
MPH.
.SHORT TERM /SUNDAY THROUGH MONDAY/...
A COLD FRONT WILL CROSS THE REGION DURING SUNDAY. THE FRONT WILL
BE ACCOMPANIED BY A PERIOD OF STEADIER RAIN LATER SUNDAY MORNING
AND SUNDAY AFTERNOON. RAINFALL AMOUNTS DURING SUNDAY ARE EXPECTED
TO RANGE FROM THREE-QUARTERS TO ONE INCH AS A LOW LEVEL JET IN THE
925-850 MB LEVEL TRAVERSES THE REGION IN ADVANCE OF THE FRONT. THE
LOW LEVEL JET WILL ALSO RESULT IN GUSTY SOUTH WINDS IN ADVANCE OF
THE FRONT. HAVE INCLUDED THE MENTION OF ISOLATED THUNDER WITH SOME
ELEVATED INSTABILITY AHEAD OF THE FRONT AND THERE CURRENTLY IS
SOME LIGHTNING SHOWING UP IN ADVANCE OF THE BOUNDARY ATTM. THE
FRONT WILL MOVE EAST OF THE DOWNEAST COAST LATER SUNDAY AFTERNOON
ENDING THE STEADIEST RAINFALL.
EXPECT PARTLY TO MOSTLY CLOUDY SKIES ACROSS NORTHERN AREAS SUNDAY
NIGHT AND MONDAY AS AN UPPER LEVEL LOW CROSSES THE REGION WITH
PARTLY CLOUDY SKIES DOWNEAST. MUCH COOLER AIR WILL FLOW IN BEHIND
THE FRONT SUNDAY NIGHT AND MONDAY. LOWS SUNDAY NIGHT WILL RANGE FROM
THE LOW TO MID 40S AND HIGHS ON MONDAY WILL RANGE FROM THE LOW TO
MID 50S NORTH AND MID TO UPPER 50S DOWNEAST.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AN UPPER LOW WILL SLOWLY MOVE EAST OF THE MARITIMES THROUGH MID
WEEK. THIS WILL KEEP A MAINLY DRY AND CHILLY WEATHER PATTERN
ACROSS THE REGION THROUGH MID WEEK.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: IFR ATTM ACROSS ALL THE TERMINALS W/FOG A NUISANCE AS
VSBYS ARE <1 MILE AT KBGR AND KBHB. CONDITIONS ARE EXPECTED TO
IMPROVE LATER THIS MORNING TO MVFR AND THEN VFR. EXPECTING
CONDITIONS TO DROP BACK TO MVFR LATER IN THE EVENING AND THEN DOWN
TO IFR BY EARLY SUNDAY MORNING.
SHORT TERM:IFR/MVFR CONDITIONS CAN BE EXPECTED ON SUNDAY IN RAIN IN
ADVANCE OF AN APPROACHING COLD FRONT. GENERALLY VFR IS EXPECTED
SUNDAY NIGHT AND BEYOND EXCEPT SOME MVFR CIGS ARE IS POSSIBLE AT
TIMES MAINLY ACROSS NORTHERN AREAS.
&&
.MARINE...
NEAR TERM: FOG WILL LEAD TO NAVIGATIONAL PROBLEMS TODAY AS A SSE
WIND CONTINUES. DECIDED TO HOIST AN SCA FOR LATER TONIGHT INTO
SUNDAY AS WINDS ARE FCST TO INCREASE TO SUSTAINED SPEEDS OF 15 TO
20 KTS AND GUSTS TO 25 KTS. LATEST WNAWAVE COMING IN LINE ATTM PER
THE LATEST OBS SHOWING WAVE HEIGHTS OF 2 FT. DECIDED TO FOLLOW THE
DAYCREW`S LEAD OF INCREASING SEAS TO 4 TO 6 FT BY SUNDAY MORNING.
SHORT TERM: A SMALL CRAFT ADVISORY IS IN EFFECT FOR SUNDAY AS
WINDS/SEAS INCREASE IN ADVANCE OF THE APPROACHING COLD FRONT.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM TO 4 PM EDT SUNDAY FOR
ANZ050>052.
&&
$$
NEAR TERM...HEWITT
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HEWITT/DUDA
MARINE...HEWITT/DUDA
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
734 PM EDT SUN SEP 22 2013
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION THROUGH THIS WEEK. ABOVE
NORMAL DAYTIME HIGHS RETURN FOR THE LATTER PART OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH MONDAY NIGHT/...
615 PM UPDATE...
INCREASED CLOUDS ACROSS NORTHERN COUNTIES OVERNIGHT. CONTINUED NW
FLOW OFF THE LAKE. HRRR ALSO ADVERTISING CLOUDS TO ERODE EXCEPT
NW. AS A RESULT...DROPPED MENTION OF FROST FOR EXTREME NE AREA
TONIGHT WITH INCREASE IN CLOUDS. ALSO DROPPED VALLEY FOG ACROSS
NORTH AND KEPT IT ACROSS SOUTHERN ONE HALF TO TWO THIRDS OF CWA.
ADJUSTED TEMP AND TD TREND. PREVIOUS DISCUSSION FOLLOWS
NW FLOW ACRS THE GT LKS AND COOL AIR ALOFT WL CONT TO BRING BKN-
OVC STRATOCU INTO THE EVE. THIS SHOULD GRDLY SCT OUT AS FLOW
EVENTUALLY TURNS MORE NE OVRNGT. RIDGING WL STRENGTHEN THRU MON
NGT AS WELL. TEMPS MAY BE COLD ENOUGH TNGT AND MON NGT FOR SOME
PATCHY FROST INVOF N OF FKL- DUJ...BUT COVG SHOULD BE PTCHY ENOUGH
FOR NO ADVISORIES ATTM.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
H5 RDG AXIS OVER OHVLY WILL FLATTEN TUE AS SHRTWV TROF ADVCS EWD
FROM WRN GRTLKS RGN. MSTR RETURN XPCD TO RMN LMTD...WHICH WILL IN
TURN LMT PCPN POTL WITH THE PASSAGE OF THIS WAVE.
WITH HIPRES DOMINANT ON TUE...NIL POPS WERE CONTD. POPS INCR WED
IN SRN ZONES OWING TO THEIR PROXIMAL LOCATION TO LOW-LVL MSTR AMID
WAVE PASSAGE. GUIDANCE INDICATES AT LEAST LOW PSBLTY OF LGT PCPN
DURG THIS TIME...BUT NWD EXTENT OF ANY PCPN WILL BE RESTRICTED BY
WAVE TRAJECTORY AND MSTR.
TEMPS WILL RECOVER MODESTLY TUE AND WED. MAXIMA GENLY IN THE MID
60S-LWR 70S LKLY BOTH DAYS...PSBLY WARMING INTO THE MID 70S ON WED
IF CLD CVR RMNS SPARSE.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
HIGH PRES WL REMAIN ACRS THE RGN THRU SAT WITH DRY WEA EXPD. AN
APRCHG CDFNT WL INCRS SHWR CHCS BY SUN. ABV SEASONAL AVG TEMPS ARE
EXPD THRU THE PD.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
STRATOCU IN NRLY FLOW WILL CONTINUE THE BETTER PART OF THE NIGHT
AT ALL TERMINALS SAVE FOR ZZV WHERE THEY WILL SCT OUT BY 2Z. LOW
END VFR CIGS /035-050/ WILL BE LAST TO VACATE FKL AND DUJ SHORTLY
BEFORE DAWN MON.
MVFR VIS OR POSSIBLY IFR VIS COULD OCCUR AT HLG/ZZV/MGW IN THE
9-13Z TIME FRAME. ANY FOG WILL BURN OFF BY 13Z YIELDING TO VFR WX.
WINDS WILL VARY DUE TO A SFC RIDGE AXIS BISECTING THE AREA.
DIRECTION WILL BE N/NNE AT ALL AIRPORTS BUT ZZV WHERE WINDS SHOULD
BE ENE. SPEEDS WILL BE LESS THAN 5KTS.
.OUTLOOK.../MONDAY NIGHT THROUGH FRIDAY/...
VFR. NO AREAS OF IFR WEATHER FORECAST.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
SYNOPSIS...98
NEAR TERM...RJK/07
SHORT TERM...KRAMAR
AVIATION...98
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1100 AM EDT SAT SEP 21 2013
.SYNOPSIS...
A COLD FRONT ACROSS THE GREAT LAKES AND OHIO VALLEY WILL PROGRESS
EAST TODAY...BEFORE MOVING THROUGH THE AREA TONIGHT. HIGH
PRESSURE BUILDS INTO THE REGION SUNDAY AND DOMINATES THE WEATHER
PATTERN FOR MUCH OF THE WEEK AHEAD.
&&
.NEAR TERM /THROUGH TONIGHT/...
14Z SFC ANALYSIS SHOWS A COLD FRONT IS LOCATED ALONG THE WRN
SPINE OF THE APPALACHIANS. 12Z RAOBS AND LATEST WATER VAPOR AND
BLENDED TOTAL PWAT SATELLITE IMAGERY SAT...IMAGERY SHOW AN
ATMOSPHERIC RIVER FROM THE TROPICAL PACIFIC AND GULF OF
MEXICO..EXITING POLEWARD UP INTO INTO ERN CANADA. THIS PLUME OF
MOISTURE AND WIDESPREAD SHOWERS...WHICH IS JUXTAPOSED WITH A SLY
LLVL JET...WILL PROGRESS INTO THE CWA FROM WEST TO EAST THIS AFTN.
SOME OF THESE SHOWERS THAT ARE COINCIDENT ALONG AND AHEAD OF FROPA
WILL BE MODERATE TO LOCALLY HEAVY WHEN PWATS INCREASE TO AROUND
1.75 INCHES. WIDESPREAD QPF AMOUNTS BETWEEN ONE-HALF TO ONE INCH
AND LOCALLY HIGHER AMNTS POSSIBLE. FLOODING THREAT WILL BE LOW
DUE TO DRY ANTECEDENT CONDITIONS. HAVE ADJUSTED POPS BASED ON
LATEST EXPECTED PROGRESSION OF THE FRONT.
OVC SKIES WILL LIMIT AMNT OF DAYTIME HEATING WITH MAX TEMPS ONLY
IN THE 70S THIS AFTN. THE ONE EXCEPTION WILL BE THE MD CHSPK BAY
AND WRN SHORE LOCATIONS...WHERE LEADING EDGE OF DENSE OVC HAS YET
TO REACH AND MAX TEMPS NEAR 80F CERTAINLY POSSIBLE. WEAK LOW- AND
MID-LVL LAPSE RATES WILL NOT SUPPORT MUCH INSTABILITY TDA. FCST
EQUIL LVLS HEIGHTS FROM THE LATEST RAP ARE LOW AND NOT SUPPORTIVE
OF TSTMS TDA. THE ONE EXCEPTION WHERE ISO TSTMS WERE KEPT IN THE
FCST IS THE WRN SHORE OF THE BAY.
RAIN/CONVECTIVE CHANCES WILL HOLD IN LONGER OVER EASTERN SECTIONS
INTO LATER TONIGHT...PARTICULARLY SOUTHERN MD NORTH TO BALTIMORE
AND HARFORD COUNTIES WITH ALL OTHER REMAINING ACTIVITY COMING TO
AN END BEFORE MIDNIGHT.
WILL HAVE TO WATCH FOR FOG DEVELOPMENT LATE TONIGHT INTO EARLY
SUNDAY DEPENDING ON EXTENT OF CLEARING AND MOIST GROUND FROM
RAINFALL. POST-FRONTAL NWLY SURGE OF DRIER AIR IN THEORY WOULD
LIMIT FOG POTENTIAL...BUT SOME SHELTERED VLYS MAY BE PROTECTED
ENOUGH FROM THE WINDS TO ALLOW FOR FOG..
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
THE FRONTAL SYSTEM EARLY SUNDAY MORNING WILL BE OVER THE DELMARVA.
A CHANCE OF SHOWERS OVER THE LOWER BAY IS POSSIBLE EARLY
SUNDAY...BUT OVERALL SKIES ON SUNDAY WILL CLEAR AND EXPECT
ABUNDANT SUNSHINE THROUGHOUT THE CWA.
FOR MON THROUGH TUE...HIGH PRESSURE WILL DOMINATE THE WEATHER
ACROSS THE REGION...ALL GUIDANCE IS CONSISTENT IN THAT REGARD.
TEMPERATURES WILL BE BELOW SEASONAL NORMALS MON AND TUE. DRY
AIRMASS OVER THE REGION WILL ALLOW NIGHTTIME MINS TO BE
PARTICULARLY COOL BOTH MON AND TUE MORNINGS.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
FOR WED...THERE IS NOW DISAGREEMENT BETWEEN THE 00Z/GFS AND NEW 00Z/21
ECMWF. THE GFS MAINTAINS UPPER LEVEL RIDGING ALONG THE EASTERN US
WHILE THE ECMWF BRINGS A POTENT-LOOKING UPPER LOW ACROSS THE MID
ATLANTIC REGION ON WED-WED NIGHT. FOR NOW...WENT WITH A MORE
OPTIMISTIC SOLN FROM THE GFS...AND THIS IS ALSO WHAT WPC SEEMS TO
THINK AS WELL. A GRADUAL WARM UP IS EXPECTED THUR AND FRI...UNDER
HIGH PRESSURE.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS FOR MOST OF THE CWA THIS MRNG EXCEPT FOR
CHO...WHICH IS SOCKED IN WITH LOW CLOUDS AND FOG. EXPECT THIS TO
TEMPORARILY MIX OUT AROUND MIDDAY UNTIL CIGS/VSBYS LOWER THIS AFTN
WHEN WIDESPREAD SHRA ARRIVE. SHRA WILL BE MOD TO LOCALLY HVY
ACROSS ALL TERMINALS AS THE COLD FRONT MOVES THRU FROM W TO E
BETWEEN 20Z-03Z. MOSTLY MVFR CIGS/VSBYS EXPECTED...PERHAPS BRIEF
IFR IN THIS HEAVIER ACTIVITY. CLEARING EXPECTED DURING THE
EVENING FROM WEST TO EAST...HOWEVER...PATCHY TO AREAS OF FOG WILL
BE POSSIBLE OVERNIGHT INTO EARLY SUNDAY.
SUNDAY THROUGH WEDNESDAY...EXPECT VFR CONDITIONS AS SUBSIDENCE
ASSOCIATED WITH HIGH PRESSURE WILL KEEP SKIES MOSTLY CLEAR TO
PARTLY CLOUDY. ONLY ISSUE COULD BE FOR CHO TAF ON WED...AS ECMWF
MODEL AT ODDS WITH GFS...ECMWF SUGGESTS SOME MVFR CLOUDS ASSOCIATED
WITH LOW PRESSURE OVER NORTH CAROLINA COULD SPREAD AS FAR NORTH TO
AFFECT CHO.
&&
.MARINE...
SLY FLOW AHEAD OF A COLD FRONT WILL STRENGTHEN THIS AFTN AND EVE.
SCA EXPANDED TO INCLUDE ALL MARINE ZONES...BUT SLY CHANNELING WILL
PRODUCE MORE FREQUENT SCA LVL GUSTS IN THE MAIN STEM OF THE CHSPK
BAY. SHOWERS AND ISOLATED THUNDERSTORMS MAY PRODUCE LOCALLY GUSTY
WINDS AS WELL DURING THE MID TO LATE AFTN AND EVE. COLD FRONT
WILL OCCUR IN THE WATERS LATE TONIGHT WITH WINDS SHIFTING TO
NORTHWEST.
NW WINDS BEHIND THE FRONT NOT AS STRONG AS THE PRE-
FRONTAL SLY WINDS...BUT DEEPER MIXING MAY PRODUCE GUSTS NEAR SCA
LVLS ON SUN. WINDS SHIFT TO NORTH DURING THE AFTN AS HIPRES BUILDS
IN. THE PRES GRADIENT DOES INCREASE SUN NIGHT INTO EARLY MON.
NORTHERLY CHANNELLING ON WINDS EARLY MON COULD RESULT IN SOME SCA
GUSTS THROUGH MID MORNING BEFORE GRADIENT SLACKENS.
&&
.TIDES/COASTAL FLOODING...
SLY WINDS AHEAD OF A COLD FRONT HAS ACCOMPANIED AN INCREASE IN
POSITIVE TIDAL DEPARTURES. ANOMALIES IN THE BAY ARE AROUND 2/3
FOOT AS OF 1030 AM...AND ARE FCST TO INCREASE TO AROUND A FT BY
HIGH TIDE THIS EVE. COMBINATION OF A RECENT FULL MOON AND THESE
EXPECTED ANOMALIES WAS ENOUGH TO ISSUE A COASTAL FLOOD ADVISORY
ALONG THE WRN SHORE FROM ANNE ARUNDEL TO HARFORD COUNTIES. WILL
ALSO NEED TO MONITOR THE POTENTIAL FOR MINOR FLOODING IN
WASHINGTON CHANNEL IF ANOMALIES INCREASE TO AROUND 3/4 FT
ABOVE /THERE IS ENOUGH UNCERTAINTY TO HOLD OFF ON AN ADIVOSRY AS
OF NOW./
WINDS WILL SHIFT FROM SOUTHERLY TO WESTERLY LATER TODAY/TONIGHT
WITH WATER LEVELS DECREASING OVERNIGHT INTO SUNDAY.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...COASTAL FLOOD ADVISORY FROM 10 PM THIS EVENING TO 2 AM EDT
SUNDAY FOR MDZ007.
COASTAL FLOOD ADVISORY FROM 6 PM TO 11 PM EDT THIS EVENING FOR
MDZ011-014.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT SUNDAY FOR ANZ530>534-
539>541-543.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ535>538-
542.
&&
$$
SYNOPSIS...JRK/
NEAR TERM...JRK/KRW
SHORT TERM...SMZ
LONG TERM...SMZ
AVIATION...JRK/SMZ
MARINE...JRK/SMZ
TIDES/COASTAL FLOODING...JRK
AREA FORECAST DISCUSSION
NWS RALEIGH NC
755 PM EDT SUN SEP 22 2013
.SYNOPSIS...
THE COLD FRONT THAT MOVED THROUGH THE REGION EARLY THIS MORNING HAS
MOVED. HIGH PRESSURE WILL BUILD INTO THE REGION AND PERSIST THROUGH
LATE TUESDAY. THE NEXT STORM SYSTEM WILL APPROACH THE AREA ON
WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
AS OF 245 PM SUNDAY...
LATEST SURFACE ANALYSIS SHOWS A COLD FRONT AND A WEAK AREA OF LOW
PRESSURE MOVING AWAY FROM THE NC COAST WITH AN AREA OF HIGH PRESSURE
CENTERED OVER THE WESTERN GREAT LAKES. DEEP LAYER MOISTURE LOCATED
OVER THE COASTAL REGION GRADUALLY THINS ACROSS THE COASTAL PLAIN AND
ESPECIALLY THE EASTERN PIEDMONT. A 1708Z AMADAR AIRCRAFT SOUNDING AT
KRDU SHOWS A VERY SHALLOW LAYER OF MOISTURE TRAPPED BELOW THE
INVERSION. VISIBLE SATELLITE IMAGERY SUGGESTS THAT THE
STRATO-CUMULUS ACROSS THE WESTERN PERIPHERY OF THE MAIN CLOUD SHIELD
AND ACROSS THE NORTHERN PIEDMONT IS BEGINNING TO WANE AS THE
MOISTURE BEGINS TO MIX OUT. NWP GUIDANCE SUGGEST THAT THIS WILL BE
THE CASE INTO THE EVENING HOURS. NWP GUIDANCE...ESPECIALLY THE NAM
AND RAP SUGGEST THAT A SHALLOW LAYER OF MOISTURE WILL SPREAD INTO
THE WESTERN PIEDMONT OVERNIGHT AND WILL LIKELY RESULT IN SOME
STRATUS OVERNIGHT. IN FACT...A FEW OF THE SREF MEMBERS ACTUALLY SPIT
OUT A LITTLE PRECIP AT KGSO AND KROA. WILL KEEP THE FORECAST DRY AND
INCLUDE PARTLY CLOUDY SKIES IN THE TRIAD REGION OVERNIGHT. BOUNDARY
LAYER PROFILERS AT BOTH CLAYTON AND RESEARCH TRIANGLE PARK THIS
AFTERNOON NOTE THE STRONGER NORTHEAST FLOW BETWEEN 2-4KFT EARLIER
TODAY HAS WEAKENED SOMEWHAT DURING THE PAST FEW HOURS AND THIS
SHOULD ALLOW THE WIND GUSTS TO RELAX DURING THE NEXT FEW HOURS.
WHILE GUSTS WILL LINGER LONGER TO THE EAST IN THE COASTAL PLAIN MOST
LOCATIONS WILL SEE A LIGHT NORTHEAST WIND OVERNIGHT WHICH WILL
MITIGATE FOG DEVELOPMENT. MINIMUM TEMPERATURE GUIDANCE FOR TONIGHT
HAS GENERALLY TRENDED DOWNWARD DURING THE PAST DAY OR TWO. WILL
FORECAST LOWS IN THE UPPER 40S IN THE NE PIEDMONT AND N COASTAL
PLAIN WITH LOWS IN THE LOWER 50S ELSEWHERE INCLUDING THE TRIAD WHERE
CLOUDS AND A STIRRING WIND KEEPS TEMPERATURES ELEVATED. -BLAES
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
AS OF 245 PM SUNDAY...
FAIR WEATHER WITH SLIGHTLY BELOW SEASONABLE TEMPERATURES IS EXPECTED
FOR MONDAY AND MONDAY NIGHT. HIGH PRESSURE CENTERED OVER THE EASTERN
GREAT LAKES WILL GRADUALLY SHIFT SOUTHEAST AND RIDGE INTO THE
CAROLINAS AND VIRGINIA AS A SHORT WAVE RIDGE OF HIGH PRESSURE BUILDS
EAST. SOME RESIDUAL LOW LEVEL MOISTURE WILL RESULT IN A FEW CUMULUS
CLOUDS DURING THE AFTERNOON ACROSS THE REGION AND SOME PATCHY
STRATUS ACROSS THE WESTERN PIEDMONT ON MONDAY NIGHT. HIGHS MONDAY
WILL RANGE IN THE 71-78 RANGE...COOLEST IN THE NORTHEAST. CHILLY
LOWS IN THE 47-54 RANGE ARE EXPECTED TUESDAY MORNING. -BLAES
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
AS OF 235 PM SUNDAY...
A FAIRLY DRY PERIOD IS EXPECTED FOR MOST OF THE LONG TERM WITH THE
EXCEPTION BEING SOME LIGHT STRATIFORM RAIN ASSOCIATED WITH A
SHORTWAVE LOW COMING OUT OF THE GULF OF MEXICO AND TRACKING ACROSS
THE DEEP SOUTH. SEASONAL MAXIMUM TEMPERATURES FROM THE MID 70S TO
NEAR 80S ARE EXPECTED FOR THE DURATION OF THE LONG TERM. LOWS WILL
GENERALLY RANGE FROM THE LOW TO UPPER 50S...NEAR OR SLIGHTLY BELOW
NORMAL FOR THIS TIME OF YEAR.
FOR TUESDAY...SURFACE HIGH WILL EXTEND INTO THE CAROLINAS FROM
SOUTHERN CANADA WITH A VERY SHARP UPPER LEVEL RIDGE ACROSS THE AREA.
EXPECT CLOUD COVER TO INCREASE LATE IN THE DAY FROM SOUTHWEST TO
NORTHEAST AS MOISTURE BEGINS TO BE ADVECTED NORTHWARD AHEAD OF THE
LOW.
ON WEDNESDAY AND THURSDAY THE LOW TO THE SOUTHWEST WILL BEGIN TO
DEEPEN WITH THE GFS COMING INTO BETTER AGREEMENT WITH THE ECMWF AND
BOTH MODELS NOW OPENING UP THE GULF OF MEXICO TO NORTHWARD MOISTURE
TRANSPORT. THE TIMING IS STILL A BIT OFF WITH THE ECMWF MORE
AGGRESSIVELY DEEPENING THE LOW AND MORE PROGRESSIVE WITH THE TIMING.
WILL STILL MORE CLOSELY FOLLOW THE ECMWF AND FORECASTED POPS AND
CLOUD COVER WILL ILLUSTRATE THIS...BRINGING CHANCE POPS INTO THE
SOUTH AND WEST ON WEDNESDAY AFTERNOON THROUGH TUESDAY MORNING. WILL
LEAVE SOME ROOM FOR THE POSSIBILITY OF THE GFS SOLUTION AND KEEP
SLIGHT CHANCE POPS THROUGH THURSDAY AFTERNOON. EXPECT RAIN TO BE
LIGHT AND STRATIFORM IN NATURE ALTHOUGH GFS FORECAST SOUNDINGS DO
HINT AT AN ELEVATED MIXED LAYER ABOVE A VERY STRONG CAP AT 950 MB.
ONE DIFFERENCE MAKER COULD BE A MUCH SMALLER SHORTWAVE IMPULSE IN
THE NORTHERN STREAM TRACKING THROUGH THE OHIO VALLEY. SLOWER GFS
TIMING ALLOWS THIS FEATURE TO INTERACT MORE WITH MOISTURE FROM THE
SOUTHERN STREAM AND TRACK ACROSS SOUTHERN VA. FOR NOW...WILL LEAVE
THE DETAILS OF THIS TO THE DAYS AHEAD.
AFTER THE LOW EXITS OFF OF THE COAST ON THURSDAY NIGHT...THINGS WILL
DRY OUT CONSIDERABLY FOR THE REST OF THE LONG TERM. A STRONG UPPER
LEVEL RIDGE WILL DOMINATE THE EASTERN CONUS ALONG WITH SURFACE HIGH
PRESSURE EXTENDING DOWN THE EAST COAST.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
AS OF 750 PM SUNDAY...
HIGH PRESSURE WILL GRADUALLY BUILD INTO THE REGION THROUGH THE
PERIOD...RESULTING IN VFR CONDITIONS TO PERSIST DURING THE NEXT 24
HOURS. OVERNIGHT...MORE IN THE WAY OF CLOUDS WILL BE IN PLACE ACROSS
THE EASTERN AND ALSO ACROSS THE WESTERN PORTIONS OF THE FORECAST
AREA...BUT THEY WILL STILL BE IN THE VFR RANGE. THEN...JUST SOME
STRATOCU IS EXPECTED AREAWIDE FOR MONDAY. WINDS WILL REMAIN LIGHT
THROUGH THE PERIOD AND GENERALLY OUT OF THE NORTH/NORTHEAST.
OUTLOOK...VFR CONDITIONS ARE EXPECTED TO PERSIST THROUGH AS LEAST
THE MIDDLE OF THE WEEK AS HIGH PRESSURE REMAINS IN CONTROL. THE NEXT
CHANCE FOR ADVERSE AVIATION CONDITIONS MAY COME WEDNESDAY INTO
THURSDAY AS A LOW PRESSURE SYSTEM APPROACHES FROM THE SOUTHWEST.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BLAES
NEAR TERM...BLAES
SHORT TERM...BLAES
LONG TERM...RE
AVIATION...KRR
AREA FORECAST DISCUSSION
NWS RALEIGH NC
155 PM EDT SAT SEP 21 2013
.SYNOPSIS...
A COLD FRONT MOVES GRADUALLY EAST ACROSS THE REGION TONIGHT AND
EARLY SUNDAY...PUSHING OFFSHORE OF NORTH CAROLINA SUNDAY AFTERNOON.
HIGH PRESSURE BUILDS OVER THE REGION BEHIND THE FRONT...REMAINING IN
PLACE AT LEAST THROUGH THE EARLY PART OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 AM SATURDAY...
THE LATEST SURFACE ANALYSIS SHOWED A COLD FRONT FROM THE LOWER GREAT
LAKES THROUGH THE OHIO AND TENNESSEE VALLEYS...HEADED TOWARD THE
TN/NC BORDER. 12Z SOUNDINGS TOWARD KGSO AND KRNK...ALONG WITH THE
UPPER-AIR ANALYSIS...SHOWED A LAYER OF GOOD DRYING AROUND 500MB...
COINCIDENT WITH SOME CLEARING OVER THE SOUTHWEST PIEDMONT AND A LACK
OF RETURNS ON NEARBY RADARS TO THE WEST. AS THE SHORTWAVE RIDGE ALSO
OVER THE AREA OF DRYING/CLEARING DAMPENS AND MOVES EAST...DIFFLUENCE
INCREASES FOR THE AFTERNOON. ALREADY...WIDESPREAD SHOWERS WERE NOTED
ON REGIONAL RADARS MOVING INTO THE WESTERN QUARTER OF THE STATE...
MOVING GRADUALLY EAST.
LIFT INCREASES FOR THE AFTERNOON OVER CENTRAL NORTH CAROLINA AS
DIFFLUENCE AHEAD OF THE SURFACE COLD FRONT MOVES EAST. IN THE MOIST
AIR MASS OVER CENTRAL NORTH CAROLINA...WITH PRECIPITABLE WATER
VALUES FROM 1.75 INCHES TO 2 INCHES THIS AFTERNOON...AND AS THE LIFT
INCREASES SCATTERED SHOWERS SHOULD DEVELOP EARLY...FOLLOWED BY MORE
NUMEROUS TO WIDESPREAD SHOWERS SPREADING GRADUALLY FROM WEST TO EAST
OVER THE AREA. THE LATEST RAP SHOWS A MODERATELY-STRONG MID-LEVEL
SHORTWAVE WEAKENING SOME AS IT MOVES EAST AND APPROACHES CENTRAL
NORTH CAROLINA...AND THE RAP 850MB THETA-E DOES NOT RECOVER FROM IN
THAT MODEL/S FORECAST FROM HIGH VALUES EARLIER THIS MORNING. ALSO...
MLCAPE OVER THE AREA BARELY REGISTERS...WITH LOW DCAPE AND LIFTED
INDICES ONLY FALLING TO AROUND 0C. GIVEN THE CURRENT UPPER-AIR AND
AIRCRAFT SOUNDINGS...ALONG WITH THE RAP FORECAST SOUNDINGS THROUGH
00Z...ALL SHOWING SOME WARMING ALOFT AROUND 500MB WHICH DOES NOT
SEEM TO CHANGE GIVEN UPSTREAM TEMPERATURES...THUNDER SHOULD BE HARD
TO COME BY AT LEAST INTO THE EARLY EVENING. TEMPERATURE PROFILES ON
RAP MODEL SOUNDINGS THROUGH 00Z ARE ALL AVERAGING AT OR RIGHT OF THE
MOIST ADIABAT. PRECIPITATION INTENSITY COULD WANE OVER OUR AREA
COMPARED TO RADAR RETURNS UPSTREAM...BUT THERE SHOULD BE ENOUGH
COVERAGE FOR NUMEROUS TO WIDESPREAD SHOWERS...AND POSSIBLY AN
ISOLATED RUMBLE OF THUNDER...FROM THE LATE AFTERNOON INTO THE
EVENING HOURS. CURRENT TEMPERATURE FORECAST IS LIKELY AT OR JUST
BEYOND THE HIGH END OF THE EXPECTED RANGE AND WILL WATCH THE
PROGRESSION OF FLEETING CLEARING ON VISIBLE IMAGERY...LIKELY NEEDING
TO MODIFY LOWER MAXES IN AREAS IN A SUBSEQUENT LATE-MORNING UPDATE.
TONIGHT...WHILE NEARLY THE ENTIRE FORECAST AREA SHOULD SEE
MEASURABLE RAIN...THE SPECIFICS OF ENDING TIMING AND AMOUNTS ARE
LESS CERTAIN. WILL STICK CLOSER TO THE NAM/GFS/WRF-ARW/WRK-NMM/SREF
MEAN TIMING...SHOWING THE HIGH POPS TAPERING DOWN LATE TONIGHT FROM
NW TO SE...BUT WILL SLOW THE EXIT DOWN BY A COUPLE OF HOURS AS A NOD
TO THE CONSISTENT ECMWF. AND...WHILE WE COULD SEE A FEW TRAINING
SHOWERS CAUSING LOCALLY HIGHER RAIN TOTALS...WILL HOLD AMOUNTS DOWN
GIVEN THIS VERY REAL POSSIBILITY OF A "CAROLINA SPLIT" IN THE PRECIP
SHIELD...AS THE BETTER DYNAMIC FORCING FOR ASCENT (INCLUDING UPPER
DIVERGENCE WITH THE POLAR STREAM JET) COULD HEAD TO OUR NORTH...
WHILE THE BETTER THERMODYNAMICS AND LOW LEVEL MASS CONVERGENCE MAY
HOLD JUST TO OUR SOUTH. LOWS 60-66 ARE IN LINE WITH STATISTICAL
GUIDANCE.
&&
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 255 AM SATURDAY...
WITH THE ABOVE REASONING IN MIND... WILL HOLD ONTO A CHANCE OF RAIN
IN THE EAST THROUGH SUNDAY MORNING. FORECAST SOUNDINGS DEPICT LOTS
OF DRY AND RATHER STABLE MID-UPPER LEVEL AIR PUSHING IN FROM THE WNW
BEHIND THE MID LEVEL TROUGH AXIS. BUT LOW LEVEL FLOW IS EXPECTED TO
BECOMING EASTERLY OR ENE BEHIND THE FRONT AS IT TAKES ON A MORE
NW-SE ORIENTATION... GIVEN THE RAPID LOOSENING OF THE HEIGHT
GRADIENT ALOFT AS THE SOUTHERN PORTION OF THE TROUGH WEAKENS. THIS
SHOULD SERVE TO HOLD CLOUDS IN LONGER ACROSS THE SRN AND ERN CWA
THROUGH MUCH OF SUNDAY... WITH LINGERING LIGHT RAIN POSSIBLE IN THE
FAR SOUTHEAST WELL INTO THE DAY. AGAIN... CONFIDENCE IN THIS
SCENARIO IS NOT TERRIBLY HIGH. WILL HOLD ONTO RAIN CHANCES MAINLY IN
THE SOUTHEAST A LITTLE LONGER INTO THE DAY. COLD AIR ADVECTION WILL
NOT BEGIN IN EARNEST UNTIL LATE IN THE DAY... ALTHOUGH THE EASTERLY
FLOW MAY ALLOW FOR LITTLE HEATING IN THE SE SECTIONS WITH TEMPS
POTENTIALLY HOLDING IN THE 70S AREAWIDE. HAVE TRIMMED A DEGREE OR
TWO OFF HIGHS... TO RANGE FROM 76 TO 80. EXPECT SCATTERED CLOUDS TO
HOLD ON OVERNIGHT ESPECIALLY IN CENTRAL/ERN PARTS OF THE FORECAST
AREA GIVEN EXPECTED MOISTURE TRAPPED BENEATH THE SUBSIDENCE
INVERSION ALOFT WITH LITTLE OPPORTUNITY FOR DISPERSION VERTICALLY OR
HORIZONTALLY. LOWS AROUND 50 NORTH TO NEAR 59 SOUTH. -GIH
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 305 AM SATURDAY...
AN AMPLIFIED...BUT RELATIVELY PROGRESSIVE UPPER LEVEL FLOW WILL LEAD
TO RIDGING OVER THE EASTERN US WHILE A SHORTWAVE MOVING ONSHORE OF
THE WEST COAST TODAY TRACKS ACROSS THE CENTRAL US MONDAY AND
TUESDAY. AT THE SURFACE...HIGH PRESSURE WILL SETTLE OVER EASTERN
CANADA AND EXTEND DOWN THE EAST COAST. THE MAIN FORECAST CHALLENGE
IS THE AFOREMENTIONED SHORTWAVE...WITH MEDIUM RANGE MODEL GUIDANCE
SHOWING SIGNIFICANTLY DIFFERENT IMPACTS. THE ECMWF PUSHES THE
SHORTWAVE THROUGH THE RIDGE...DRAWING MORE MOISTURE NORTH FROM THE
GULF OF MEXICO ATOP THE SURFACE RIDGE...LEADING TO MORE CLOUD
COVER/PRECIP...AND EVENTUALLY CYCLOGENESIS ALONG THE STALLED FRONTAL
ZONE OFF THE SOUTHEAST COAST. THE GFS LIFTS THE SHORTWAVE
TOWARD THE GREAT LAKES AND LEAVES THE SOUTHEAST US DRY. WPC PREFERS
AN ECMWF-LIKE SOLUTION BASED AN ENSEMBLE GUIDANCE...WHICH WOULD
STILL KEEP MOST PRECIP SOUTH OF THE CWA AND LIMIT A COLD AIR DAMMING
SCENARIO. WILL INDICATE A CHANCE POP ACROSS SOUTHERN COUNTIES ON
WEDNESDAY...WITH JUST A SLIGHT CHANCE TO THE NORTH. HIGHS WILL
GENERALLY BE AT OR BELOW NORMAL FOR MOST OF THE WEEK...COOLEST
TUESDAY/WEDNESDAY WITH ADDED CLOUD COVER...AND SHOULD RISE BACK TO
AROUND OR JUST ABOVE NORMAL BY THE END OF THE WEEK AHEAD OF THE NEXT
COLD FRONT.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AS OF 155 PM SATURDAY...
AREAS OF MVFR CEILINGS HAVE HELD FIRM INTO EARLY AFTERNOON
ESPECIALLY OVER THE WESTERN PIEDMONT. WHILE THERE SHOULD BE SOME
LIFTING OF THE CEILINGS EVEN THERE FOR A PERIOD...SCATTERED SHOWERS
AND AREAS OF RAIN...WITH INCREASING MOISTURE...WILL SPREAD EAST AND
RESULT IN A RETURN TO SUB-VFR CONDITIONS THIS EVENING. OVERNIGHT...
GUIDANCE IS CONSISTENT WITH NUMEROUS TO WIDESPREAD AREAS OF IFR
CONDITIONS DUE TO CEILINGS ACROSS CENTRAL NORTH CAROLINA...AS AREAS
OF SHOWERS GRADUALLY MOVE EAST. IFR CONDITIONS CONTINUE INTO EARLY
SUNDAY BEFORE CONDITIONS INCREASE TO MVFR DURING THE MORNING...
POSSIBLY TO VFR BY SUNDAY AFTERNOON. BEYOND THE 18Z VALID TAF
PERIOD...SOME MVFR CEILINGS COULD CONTINUE INTO THE AFTERNOON SUNDAY
MAINLY TOWARD KFAY AND KRWI. BY SUNDAY NIGHT...WIDESPREAD VFR
CONDITIONS ARE EXPECTED...AND THESE CONDITIONS SHOULD LARGELY
PERSIST THROUGH THE MIDDLE OF THE WEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...DJF/HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...SMITH
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1015 AM EDT SAT SEP 21 2013
.SYNOPSIS...
A COLD FRONT WILL MOVE SLOWLY EASTWARD THROUGH THE AREA LATE TODAY
THROUGH SUNDAY MORNING. HIGH PRESSURE WILL BUILD BACK OVER THE
REGION EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 AM SATURDAY...
THE LATEST SURFACE ANALYSIS SHOWED A COLD FRONT FROM THE LOWER GREAT
LAKES THROUGH THE OHIO AND TENNESSEE VALLEYS...HEADED TOWARD THE
TN/NC BORDER. 12Z SOUNDINGS TOWARD KGSO AND KRNK...ALONG WITH THE
UPPER-AIR ANALYSIS...SHOWED A LAYER OF GOOD DRYING AROUND 500MB...
COINCIDENT WITH SOME CLEARING OVER THE SOUTHWEST PIEDMONT AND A LACK
OF RETURNS ON NEARBY RADARS TO THE WEST. AS THE SHORTWAVE RIDGE ALSO
OVER THE AREA OF DRYING/CLEARING DAMPENS AND MOVES EAST...DIFFLUENCE
INCREASES FOR THE AFTERNOON. ALREADY...WIDESPREAD SHOWERS WERE NOTED
ON REGIONAL RADARS MOVING INTO THE WESTERN QUARTER OF THE STATE...
MOVING GRADUALLY EAST.
LIFT INCREASES FOR THE AFTERNOON OVER CENTRAL NORTH CAROLINA AS
DIFFLUENCE AHEAD OF THE SURFACE COLD FRONT MOVES EAST. IN THE MOIST
AIR MASS OVER CENTRAL NORTH CAROLINA...WITH PRECIPITABLE WATER
VALUES FROM 1.75 INCHES TO 2 INCHES THIS AFTERNOON...AND AS THE LIFT
INCREASES SCATTERED SHOWERS SHOULD DEVELOP EARLY...FOLLOWED BY MORE
NUMEROUS TO WIDESPREAD SHOWERS SPREADING GRADUALLY FROM WEST TO EAST
OVER THE AREA. THE LATEST RAP SHOWS A MODERATELY-STRONG MID-LEVEL
SHORTWAVE WEAKENING SOME AS IT MOVES EAST AND APPROACHES CENTRAL
NORTH CAROLINA...AND THE RAP 850MB THETA-E DOES NOT RECOVER FROM IN
THAT MODEL/S FORECAST FROM HIGH VALUES EARLIER THIS MORNING. ALSO...
MLCAPE OVER THE AREA BARELY REGISTERS...WITH LOW DCAPE AND LIFTED
INDICES ONLY FALLING TO AROUND 0C. GIVEN THE CURRENT UPPER-AIR AND
AIRCRAFT SOUNDINGS...ALONG WITH THE RAP FORECAST SOUNDINGS THROUGH
00Z...ALL SHOWING SOME WARMING ALOFT AROUND 500MB WHICH DOES NOT
SEEM TO CHANGE GIVEN UPSTREAM TEMPERATURES...THUNDER SHOULD BE HARD
TO COME BY AT LEAST INTO THE EARLY EVENING. TEMPERATURE PROFILES ON
RAP MODEL SOUNDINGS THROUGH 00Z ARE ALL AVERAGING AT OR RIGHT OF THE
MOIST ADIABAT. PRECIPITATION INTENSITY COULD WANE OVER OUR AREA
COMPARED TO RADAR RETURNS UPSTREAM...BUT THERE SHOULD BE ENOUGH
COVERAGE FOR NUMEROUS TO WIDESPREAD SHOWERS...AND POSSIBLY AN
ISOLATED RUMBLE OF THUNDER...FROM THE LATE AFTERNOON INTO THE
EVENING HOURS. CURRENT TEMPERATURE FORECAST IS LIKELY AT OR JUST
BEYOND THE HIGH END OF THE EXPECTED RANGE AND WILL WATCH THE
PROGRESSION OF FLEETING CLEARING ON VISIBLE IMAGERY...LIKELY NEEDING
TO MODIFY LOWER MAXES IN AREAS IN A SUBSEQUENT LATE-MORNING UPDATE.
TONIGHT...WHILE NEARLY THE ENTIRE FORECAST AREA SHOULD SEE
MEASURABLE RAIN...THE SPECIFICS OF ENDING TIMING AND AMOUNTS ARE
LESS CERTAIN. WILL STICK CLOSER TO THE NAM/GFS/WRF-ARW/WRK-NMM/SREF
MEAN TIMING...SHOWING THE HIGH POPS TAPERING DOWN LATE TONIGHT FROM
NW TO SE...BUT WILL SLOW THE EXIT DOWN BY A COUPLE OF HOURS AS A NOD
TO THE CONSISTENT ECMWF. AND...WHILE WE COULD SEE A FEW TRAINING
SHOWERS CAUSING LOCALLY HIGHER RAIN TOTALS...WILL HOLD AMOUNTS DOWN
GIVEN THIS VERY REAL POSSIBILITY OF A "CAROLINA SPLIT" IN THE PRECIP
SHIELD...AS THE BETTER DYNAMIC FORCING FOR ASCENT (INCLUDING UPPER
DIVERGENCE WITH THE POLAR STREAM JET) COULD HEAD TO OUR NORTH...
WHILE THE BETTER THERMODYNAMICS AND LOW LEVEL MASS CONVERGENCE MAY
HOLD JUST TO OUR SOUTH. LOWS 60-66 ARE IN LINE WITH STATISTICAL
GUIDANCE.
&&
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 255 AM SATURDAY...
WITH THE ABOVE REASONING IN MIND... WILL HOLD ONTO A CHANCE OF RAIN
IN THE EAST THROUGH SUNDAY MORNING. FORECAST SOUNDINGS DEPICT LOTS
OF DRY AND RATHER STABLE MID-UPPER LEVEL AIR PUSHING IN FROM THE WNW
BEHIND THE MID LEVEL TROUGH AXIS. BUT LOW LEVEL FLOW IS EXPECTED TO
BECOMING EASTERLY OR ENE BEHIND THE FRONT AS IT TAKES ON A MORE
NW-SE ORIENTATION... GIVEN THE RAPID LOOSENING OF THE HEIGHT
GRADIENT ALOFT AS THE SOUTHERN PORTION OF THE TROUGH WEAKENS. THIS
SHOULD SERVE TO HOLD CLOUDS IN LONGER ACROSS THE SRN AND ERN CWA
THROUGH MUCH OF SUNDAY... WITH LINGERING LIGHT RAIN POSSIBLE IN THE
FAR SOUTHEAST WELL INTO THE DAY. AGAIN... CONFIDENCE IN THIS
SCENARIO IS NOT TERRIBLY HIGH. WILL HOLD ONTO RAIN CHANCES MAINLY IN
THE SOUTHEAST A LITTLE LONGER INTO THE DAY. COLD AIR ADVECTION WILL
NOT BEGIN IN EARNEST UNTIL LATE IN THE DAY... ALTHOUGH THE EASTERLY
FLOW MAY ALLOW FOR LITTLE HEATING IN THE SE SECTIONS WITH TEMPS
POTENTIALLY HOLDING IN THE 70S AREAWIDE. HAVE TRIMMED A DEGREE OR
TWO OFF HIGHS... TO RANGE FROM 76 TO 80. EXPECT SCATTERED CLOUDS TO
HOLD ON OVERNIGHT ESPECIALLY IN CENTRAL/ERN PARTS OF THE FORECAST
AREA GIVEN EXPECTED MOISTURE TRAPPED BENEATH THE SUBSIDENCE
INVERSION ALOFT WITH LITTLE OPPORTUNITY FOR DISPERSION VERTICALLY OR
HORIZONTALLY. LOWS AROUND 50 NORTH TO NEAR 59 SOUTH. -GIH
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 305 AM SATURDAY...
AN AMPLIFIED...BUT RELATIVELY PROGRESSIVE UPPER LEVEL FLOW WILL LEAD
TO RIDGING OVER THE EASTERN US WHILE A SHORTWAVE MOVING ONSHORE OF
THE WEST COAST TODAY TRACKS ACROSS THE CENTRAL US MONDAY AND
TUESDAY. AT THE SURFACE...HIGH PRESSURE WILL SETTLE OVER EASTERN
CANADA AND EXTEND DOWN THE EAST COAST. THE MAIN FORECAST CHALLENGE
IS THE AFOREMENTIONED SHORTWAVE...WITH MEDIUM RANGE MODEL GUIDANCE
SHOWING SIGNIFICANTLY DIFFERENT IMPACTS. THE ECMWF PUSHES THE
SHORTWAVE THROUGH THE RIDGE...DRAWING MORE MOISTURE NORTH FROM THE
GULF OF MEXICO ATOP THE SURFACE RIDGE...LEADING TO MORE CLOUD
COVER/PRECIP...AND EVENTUALLY CYCLOGENESIS ALONG THE STALLED FRONTAL
ZONE OFF THE SOUTHEAST COAST. THE GFS LIFTS THE SHORTWAVE
TOWARD THE GREAT LAKES AND LEAVES THE SOUTHEAST US DRY. WPC PREFERS
AN ECMWF-LIKE SOLUTION BASED AN ENSEMBLE GUIDANCE...WHICH WOULD
STILL KEEP MOST PRECIP SOUTH OF THE CWA AND LIMIT A COLD AIR DAMMING
SCENARIO. WILL INDICATE A CHANCE POP ACROSS SOUTHERN COUNTIES ON
WEDNESDAY...WITH JUST A SLIGHT CHANCE TO THE NORTH. HIGHS WILL
GENERALLY BE AT OR BELOW NORMAL FOR MOST OF THE WEEK...COOLEST
TUESDAY/WEDNESDAY WITH ADDED CLOUD COVER...AND SHOULD RISE BACK TO
AROUND OR JUST ABOVE NORMAL BY THE END OF THE WEEK AHEAD OF THE NEXT
COLD FRONT.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
AS OF 1015 AM SATURDAY...
IFR/LIFR CEILINGS WEST OF U.S. 1...MAINLY WEST OF KRDU TOWARD THE
TRIAD...SHOULD LIFT TO VFR THIS MORNING. VISIBLE SATELLITE IMAGERY
SHOWS A SLOW EROSION OF THE LOW CLOUDS UNDERNEATH THE HIGH CLOUDS.
ELSEWHERE...WITH A WEAK WARM FRONTAL ZONE SITTING OVER CENTRAL NC...
CIGS/VSBYS AT RDU/FAY WILL VARY BETWEEN MVFR AND VFR...WITH VFR
CONDITIONS DOMINANT BY 16Z. WIDESPREAD RAIN AND A FEW STORMS SHOULD
AFFECT INT/GSO BETWEEN 20Z AND 03Z THIS EVENING...AT RDU FROM 21Z
UNTIL AROUND 05Z...AND AT RWI/FAY AFTER 22Z THROUGH THE END OF THE
TAF VALID PERIOD. CIGS WITHIN THESE SHOWERS AND ISOLATED STORMS
SHOULD VARY BETWEEN MVFR AND VFR WITH MOSTLY MVFR VSBYS. CIGS SHOULD
START TO DROP BACK TO MVFR/IFR STARTING BETWEEN 03Z AND 06Z JUST
BEHIND THE FRONT...LASTING THROUGH 12Z SUNDAY MORNING.
LOOKING BEYOND 12Z SUNDAY MORNING...CIGS ARE EXPECTED TO REBOUND TO
VFR SLOWLY WEST TO EAST SUNDAY AS THE FRONT PUSHES EASTWARD...
ALTHOUGH IMPROVEMENT MAY NOT REACH FAY UNTIL AFTER 18Z SUNDAY AS A
FEW MODELS HAVE RAIN HOLDING IN ACROSS OUR SOUTHEAST WELL INTO THE
DAY. OTHERWISE...VFR CONDITIONS SHOULD DOMINATE FROM SUNDAY NIGHT
THROUGH WEDNESDAY AS HIGH PRESSURE BUILDS IN FROM THE NORTH WITH DRY
AIR MOVING IN.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...DJF/HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...SMITH
AVIATION...DJF/HARTFIELD
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
750 PM EDT SUN SEP 22 2013
.SYNOPSIS...
COOL CANADIAN HIGH PRESSURE WILL BUILD EAST ACROSS THE GREAT LAKES
THROUGH MONDAY. THIS HIGH WILL REMAIN IN THE GREAT LAKES VICINITY
THROUGH MOST OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
THE GREAT LAKES REGION REMAINS BETWEEN AN UPPER LEVEL TROUGH OVER
QUEBEC AND A RIDGE BUILDING OVER THE UPPER MIDWEST. ENOUGH
TROUGHINESS REMAINS ALONG WITH THE 850MB COLD POOL(TEMPS DOWN TO -2C
OVER ONTARIO) TO MAINTAIN CONSIDERABLE CLOUD COVER ACROSS THE
SOUTHERN ONTARIO AND QUEBEC THIS AFTERNOON. CLOUDS ALSO EXTEND
DOWNWIND OFF ALL OF THE GREAT LAKES...EVEN NEARLY OVERCAST SKIES
OVER LAKE MICHIGAN DIRECTLY BENEATH THE SURFACE HIGH. AS NOTED
EARLY...NAM SOUNDINGS ARE ALREADY RUNNING A LITTLE TOO OPTIMISTIC
WITH CLEARING WHILE RUC SOUNDINGS KEEP EASTERN AREAS CLOUDY ALL
NIGHT BENEATH THE LOWERING INVERSION. HRRR IS SIMILAR. WILL CARRY
A MOSTLY CLEAR FORECAST TOWARDS FINDLAY WITH MOSTLY CLOUDY SKIES
FOR MOST OF THE NIGHT ACROSS THE EASTERN HALF OF THE AREA. CAN
ALREADY SEE CLOUDS RETURNING WEST OF CLEVELAND WITH LITTLE MESO
LOW COMING ASHORE NEAR LAKE COUNTY. MOS GUIDANCE ALSO TOO QUICK
WITH THE CLEARING TREND SO WILL GO 2-5 DEGREES WARMER TONIGHT FOR
AREAS EAST OF A CLE-CAK LINE. TEMPERATURES WILL FALL QUICKLY WITH
ANY SIZABLE BREAKS IN THE CLOUDS. HAVE ADDED A FEW SHOWERS TO
LAKE/ASHTABULA/GEAUGA COUNTIES WITH THE MESO LOW. A FEW RADAR
RETURNS MIGHT ACTUALLY ACCUMULATE 0.01 INCHES EARLY THIS EVENING.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
A DRY STRETCH OF WEATHER WITH COOL NIGHTS TO FOLLOW DURING THE SHORT
TERM. HIGH PRESSURE WILL REMAIN OVER THE EASTERN GREAT LAKES THROUGH
TUESDAY...SHIFTING SLIGHTLY TO THE NORTH ON WEDNESDAY. DIURNAL CU
EXPECTED ONCE AGAIN ON MONDAY BEFORE WE FINALLY MIX OUT OUR MOISTURE
AND CLEAR FOR MONDAY NIGHT. THIS WILL SET UP FOR A CHILLY NIGHT ON
MONDAY WITH MOST INLAND AREAS DIPPING TO NEAR 40 DEGREES. SOME OF
THE COOLER SPOTS IN NE OHIO WILL DIP INTO THE UPPER 30S WITH MID 30S
FOR INTERIOR NW PA. HAVE INCLUDED AREAS OF FROST FOR THOSE COOLEST
SPOTS AND THERE IS POTENTIAL THAT WE MAY NEED A FROST ADVISORY FOR
ERIE AND CRAWFORD PA. A HEALTHY DIURNAL SPREAD WILL ALLOW HIGHS TO
RECOVER INTO THE LOW AND MID 60S FOR TUESDAY...THEN COOL BACK INTO
THE 40S FOR TUESDAY NIGHT. LEANED THE FORECAST TOWARDS THE RAW MODEL
TEMPERATURES WHICH ARE SLIGHTLY COOLER THAN MOS GUIDANCE THROUGH THE
SHORT TERM.
UPPER LEVEL LOW OVER THE GREAT BASIN WILL MOVE NORTHEAST ACROSS THE
PLAINS ON MONDAY AND ENCOUNTER SOME RESISTANCE BY THE HIGH AMPLITUDE
UPPER LEVEL RIDGE OVER THE GREAT LAKES REGION. THE UPPER LOW WILL
WEAKEN AS IT SLIDES EAST ACROSS THE OHIO VALLEY ON TUESDAY NIGHT AND
WEDNESDAY. MODELS KEEP THE QPF SOUTH OF THE FORECAST AREA AND GIVEN
THE RESIDENT DRY AIRMASS IN PLACE...WILL KEEP THE FORECAST DRY WITH
JUST SOME INCREASE IN CLOUDS ON WEDNESDAY. TEMPS WILL RETURN TO NEAR
70 MOST AREAS.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
A RIDGE OF HIGH PRESSURE WILL BE OVER THE AREA TO START THE FORECAST
PERIOD AND THEN IT WILL SHIFT SLOWLY EAST AS A WEAKENING COLD FRONT
ADVANCES TOWARDS THE REGION. SOME QUESTION AS TO THE TIMING OF THE
FRONT FOR LATE IN THE WEEKEND. THE 12Z GFS IS MUCH QUICKER THAN THE
ECMWF AND THE CANADIAN MODEL. AT THIS TIME LEANING MORE TOWARD THE
SLOWER MODELS. SO THE MAIN CHANCE OF PRECIPITATION WILL BE ON SUNDAY
INTO SUNDAY NIGHT. IT SEEMS STABLE SO ONLY FORECASTING SHOWERS. USED
A BLEND OF GUIDANCE FOR THE NEAR NORMAL TEMPERATURES.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
AREAS OF MVFR CLOUD COVER HAVE DEVELOPED ALONG A TROUGH/OUTFLOW
BOUNDARY THAT WAS MOVING ACROSS THE WESTERN HALF OF LAKE ERIE.
THERE WERE ALSO A FEW LIGHT SHOWERS EAST OF KCLE IN THE VICINITY
OF KYNG. THESE SHOWERS AND THE MVFR CEILINGS SHOULD ONLY AFFECT
KCLE AND KYNG...BUT MAY CLIP KMFD. OTHERWISE CEILINGS SHOULD LIFT
THROUGH THE EVENING AND SHOULD TAKE UP RESIDENCE AROUND 3500 FEET.
THESE CLOUDS SHOULD THEN PERSIST INTO MONDAY MORNING. IT APPEARS
AT THIS TIME THAT THE CLEARING MAY OCCUR FROM EAST TO WEST INTO
MONDAY AFTERNOON AS THE TRAPPED LOW LEVEL MOISTURE GETS CAUGHT IN
THE SHIFT OF THE WINDS TO A NORTHEASTERLY DIRECTION.
OUTLOOK...MAINLY VFR.
&&
.MARINE...
A RIDGE OF HIGH PRESSURE WILL BE BUILDING IN TONIGHT. WILL LET THE
SMALL CRAFT ADVISORY AND RIP CURRENT RISK EXPIRE/CANCEL AS THE WINDS
AND WAVES ARE DECREASING. HOWEVER AS THE RIDGE IS BUILDING IN
TONIGHT THE NORTHEAST FLOW GRADIENT WILL INCREASE AND THAT COULD
CAUSE THE WAVES TO GET CLOSE TO SMALL CRAFT ADVISORY CRITERIA AND
AGAIN ON MONDAY. HOWEVER...AT THIS TIME IT SEEMS THAT 2 TO 4 FOOT
WAVES SHOULD HANDLE IT. AS THE RIDGE BECOMES STRONGER MONDAY NIGHT
AND TUESDAY THE WINDS WILL BE LIGHTER...THUS DECREASING THE WAVES.
THE RIDGE WILL BE AROUND THE LAKE THROUGH FRIDAY AND THAT WILL MEAN
AN EAST OR NORTHEAST FLOW. AT THIS TIME A SMALL CRAFT ADVISORY IS
NOT EXPECTED AS THE NORTHEAST FLOW SHOULD NOT BE STRONG ENOUGH TO
CAUSE 3 TO 5 FOOT WAVES BUT THIS WILL HAVE TO BE WATCHED AS
NORTHEAST FLOWS ARE NOTORIOUS FOR CAUSING HIGH WAVES ESPECIALLY ON
THE WEST END OF THE LAKE BECAUSE OF THE LONG FETCH.
A COLD FRONT WILL BE APPROACHING THE LAKE FOR LATE IN THE UPCOMING
WEEKEND SHIFTING THE WINDS TO SOUTHERLY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KEC
NEAR TERM...KEC/OUDEMAN
SHORT TERM...KEC
LONG TERM...KIELTYKA
AVIATION...MULLEN
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS PORTLAND OR
255 AM PDT SAT SEP 21 2013
.SYNOPSIS...ADDITIONAL RAIN SHOWERS WILL CONTINUE THROUGH SATURDAY
WITH PERHAPS A FEW LIGHTNING STRIKES SCATTERED ABOUT NORTHWEST
OREGON. A STRONGER FRONT WILL BRING WINDY CONDITIONS TO THE
COAST...BREEZY CONDITIONS INLAND...AND ANOTHER ROUND OF WIDESPREAD
RAIN TO THE AREA SUNDAY. EXPECT COOL TEMPERATURES AND PERIODS OF
SHOWERS FOR THE FIRST HALF OF NEXT WEEK. DRIER CONDITIONS LOOK IN
STORE FOR THE SECOND HALF OF THE WORK WORK.
&&
.SHORT TERM...INFRARED SATELLITE IMAGERY EARLY THIS MORNING REVEALS
THE STRETCHING COLD FRONT THAT BROUGHT RAIN SHOWERS TO THE REGION
EARLIER THIS AFTERNOON AND EVENING IS NOW WELL EAST OF THE CASCADE
CREST. ALSO...A CLUSTER OF COOLING CLOUD TOPS CURRENTLY RESIDES JUST
OFF THE SOUTHWEST OREGON AND NORTHERN CALIFORNIA COASTS WITH A DECENT
AMOUNT OF LIGHTNING STRIKES OCCURRING OVERNIGHT IN THIS REGION.
LIGHTNING HAS BEEN OBSERVED OFFSHORE ABOUT AS FAR NORTH AS TILLAMOOK.
BASED ON SATELLITE EXTRAPOLATION...THE BULK OF THE CONVECTION LOOKS
LIKE IT WILL FLIRT WITH THE COAST AND OUR SOUTHERN INTERIOR ZONES
THIS MORNING AS MOST OF THE CONVECTION SLIDES EASTWARD INTO MEDFORDS
CWA. HRRR AND EVEN THE GLOBAL MODELS SUGGEST CONVECTION WILL BE MUCH
MORE LIMITED NORTH AND EAST OF SALEM TODAY WHEN COMPARED TO POINTS
SOUTH AND WEST. THIS SEEMS PLAUSIBLE GIVEN THE TRACK OF THE 500MB
COLD POOL. HOWEVER...CANNOT RULE OUT A THUNDERSTORM OR TWO NORTH AND
EAST OF SALEM DURING PEAK HEATING SO IT WAS RETAINED FOR THE
AFTERNOON HOURS.
BRIEF SHORTWAVE RIDGING SATURDAY NIGHT WILL CAUSE SHOWERS TO DIE AND
BECOME MUCH MORE ISOLATED IN NATURE. THE BREAK IN THE WET WEATHER
WILL BE SHORT LIVED HOWEVER...AS A SHORTWAVE TROUGH DIVES
SOUTHEASTWARD OUT OF THE GULF OF ALASKA. STRONG UPPER LEVEL SUPPORT
WILL ALLOW AN ORGANIZED FRONT TO MOVE SOUTHEASTWARD ACROSS THE AREA
SUNDAY. ISENTROPIC LIFT AHEAD OF THIS FRONT WILL PRODUCE WIDESPREAD
RAIN...LIKELY IN EXCESS OF AN INCH ACROSS THE COAST RANGE...WITH UP
TO A HALF INCH FOR THE WILLAMETTE VALLEY SUNDAY AFTERNOON AND
EVENING.
EXPECT WINDS TO INCREASE AREA WIDE SUNDAY MORNING AS PRESSURE
GRADIENTS INCREASE. MODELS CONTINUE TO DISAGREE ON THE POTENTIAL FOR
HIGH WIND CRITERIA FOR THE COAST. THE NAM APPEARS MORE FAVORABLE
WHILE THE GFS IS SLOWLY TRENDING WEAKER AND HAS WINDS 10 TO 15 KTS
LESS THAN THE NAM AT 925MB AND 850MB. SO FOR NOW...WILL HOLD OFF
ON A HIGH WIND WATCH FOR THE COAST...AND HIGHLIGHT THE FIRST OF THE
SEASON WIND EVENT FOR THE COAST WITH AN SPS. EVEN ISOLATED POWER
OUTAGES SEEM LIKE A DECENT BET FOR THE WILLAMETTE VALLEY WHERE 30 TO
35 MPH WINDS WILL LIKELY TOPPLE A FEW TREES GIVEN MANY AREAS HAVE
NOT EXPERIENCED ANY WINDS OF SIGNIFICANCE IN MONTHS.
ONCE THE FRONT SLIDES SOUTHEAST OF THE AREA SUNDAY EVENING...STRONG
ZONAL FLOW AND LOW LEVEL INSTABILITY SHOULD KEEP SHOWERS GOING
SUNDAY NIGHT INTO MONDAY. HOWEVER...THE COLD AIR ALOFT AND UPPER
LEVEL DYNAMICS LOOK TO REMAIN WELL TO OUR NORTH...WHICH SHOULD
RESULT IN SHOWERS HAVING AN INCREASINGLY HARD TIME MAKING IT INTO
THE WILLAMETTE VALLEY DURING THIS TIME. AS A RESULT...KEPT THE
HIGHEST CHANCES FOR RAIN ALONG THE COAST...CASCADES AND OUR FAR
NORTHERN ZONES.
THE MAIN GULF OF ALASKA TROUGH AND A SECONDARY COLD FRONT WILL
EVENTUALLY SWING THROUGH THE REGION TUESDAY. THIS SHOULD BRING A
BETTER THREAT FOR SHOWERS AREA WIDE SO POPS WERE NUDGED UPWARD
ACCORDINGLY. IN ADDITION...SNOW LEVELS WILL ONCE AGAIN DIP INTO THE
6KFT RANGE...IF NOT A TOUCH LOWER. /NEUMAN
.LONG TERM...MONDAY THROUGH FRIDAY...ONSHORE FLOW AHEAD OF THE COLD
UPPER TROUGH OFF THE B.C. COAST SHOULD RESULT COOL AND BREEZY
CONDITIONS...ALONG WITH ADDITIONAL ROUNDS OF SHOWERS MONDAY AND
TUESDAY AS AN UPPER LEVEL TROUGH DROPS INTO THE PACIFIC NORTHWEST.
THE UPPER LOW WILL SHIFT SOUTH AND EAST OF THE AREA THROUGH THE DAY
ON WEDNESDAY ALLOWING SHOWERS TO DIMINISH...THOUGH CLOUDS LINGER AS
WE REMAIN IN CYCLONIC FLOW ALOFT. EXPECT AN UPPER LEVEL RIDGE WILL
BE OFFSHORE ON WEDNESDAY EVENING AND ATTEMPT TO SLOWLY PUSH ONSHORE.
THE FLOW TURNS NORTH TO NORTHEASTERLY WHICH WILL ALLOW THE AREA TO
DRY OUT THROUGH AT LEAST EARLY FRIDAY. EXPECT SOME OF THE COOLEST
OVERNIGHT LOWS OF THE SEASON DURING THE LATTER HALF OF THE EXTENDED
PERIOD...AND WE MAY SEE SOME MORNING LOW CLOUDS AND FOG. KMD/ROCKEY
&&
.AVIATION...A MOIST AND UNSTABLE AIRMASS WILL BRING A THREAT OF
SHOWERS AND THUNDERSTORMS TODAY...WITH VARYING FLIGHT CONDITIONS.
EXPECT VFR CONDITIONS TO BE THE MOST PREVALENT...BUT MVFR CONDITIONS
ARE LIKELY TO OCCUR AT TIMES THROUGHOUT NW OREGON. COASTAL AIRPORTS
ARE LIKELY TO SEE THE MOST TIME WITH MVFR CONDITIONS HOWEVER. IFR
CIGS AT KONP EARLY THIS MORNING ARE LIKELY TO GIVE WAY TO VFR OR
MVFR CONDITION LATE THIS MORNING...ESPECIALLY AFTER 18Z.
AIR MASS BEGINS TO STABILIZE AFTER 02Z AS THE UPPER TROUGH PASSES
WITH VFR CONDITIONS LIKELY TO DOMINATE IN THE EVENING BETWEEN 02Z
AND 08Z. EXPECT A RETURN TO MVFR CONDITIONS AFTER 08Z MOST AREAS AS
AIR MASS STABILIZES.
KPDX AND APPROACHES...VFR CONDITIONS LIKELY TO PREVAIL TODAY INTO
THE EVENING. HOWEVER...MVFR CIGS ARE LIKELY TO OCCUR SPORADICALLY
TODAY...ESPECIALLY AS SHOWERS AND ISOLATED THUNDERSTORMS DEVELOP.
&&
.MARINE...WINDS EXPECTED TO REMAIN BELOW SMALL CRAFT CRITERIA
THROUGH THIS EVENING AS A TROUGH OF LOW PRES MOVES ACROSS THE
WATERS. SEAS ALSO WILL SUBSIDE SOME...GOING UNDER 10 FT BY THE
AFTERNOON.
WINDS EXPECTED TO RAMP UP LATE TONIGHT AND SUN AHEAD OF AN OCCLUDED
FRONT THAT IS EXPECTED TO MOVE E ACROSS THE COASTAL WATERS SUN
AFTERNOON. WILL CONTINUE WITH THE GALE WATCH FOR THE OUTER WATERS
SUN AS STRONG PRES GRADIENTS PRECEDE THE FRONT. COMPUTER MODELS
HOWEVER INDICATE SOME WEAKENING OF THE FRONT AS IT APPROACHES THE
COAST AT THE END OF THE DAY...AND WITH WINDS AHEAD OF THE FRONT
BLOWING A LITTLE OFFSHORE IT IS NOT CLEAR THAT GALE FORCE WINDS WILL
EXTEND INTO THE INNER WATERS...ALTHOUGH IT IS NOT OUT OF THE
QUESTION EITHER. STEEP SHORT PERIOD SEAS WILL BUILD WITH THE WINDS
SUN...THEN A LONGER PERIOD WESTERLY SWELL WILL BUILD SUN NIGHT AND
MON...BRINGING SEAS TO AROUND 15 FT MON.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...GALE WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING FOR
WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR FROM 10 TO
60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 AM PDT THIS
MORNING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL
10 AM PDT THIS MORNING.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 4 PM
THIS AFTERNOON TO 8 PM PDT THIS EVENING.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
948 PM EDT SUN SEP 22 2013
.SYNOPSIS...
HIGH PRESSURE WILL BUILD SOUTH ACROSS THE AREA FROM THE GREAT LAKES
TONIGHT THROUGH TUESDAY. AN UPPER LEVEL AREA OF LOW PRESSURE
WILL MOVE ACROSS THE AREA WEDNESDAY FOLLOWED BY RETURN OF HIGH
PRESSURE FOR NEXT WEEKEND.
&&
.NEAR TERM /THROUGH MONDAY/...
AS OF 945 PM EDT SUNDAY...
HIGH PRESSURE CENTERED OVER THE GREAT LAKES BUILD SOUTH TONIGHT.
SHALLOW LAYER OF MOISTURE TRAPPED BELOW THE INVERSION ACROSS THE
PIEDMONT AND FOOTHILLS TONIGHT. THE CMC/NAM AND RAP HINT AT
RETURNING MOISTURE BACK INTO OUR AREA OVERNIGHT. A FEW OF THE SREF
MEMBERS ACTUALLY PRINT OUT A LITTLE PRECIP AT KROA. BELIEVE THE
MODELS ARE OVERDONE AND TOO FAST IN RETURNING MOISTURE. USED A
BLEND OF GUIDANCE FOR CLOUD COVER TONIGHT ALLOW FOR SOME
STRATUS/STRATOCU FORMING UNDER THE SUBSIDENCE INVERSION IN THE
EAST.
PLAYED LOW TEMPERATURES OVERNIGHT CLOSE TO COOLER ADJMAVBC
WITH READINGS FROM THE LOWER 40S IN THE WEST TO THE LOWER 50S IN
THE EAST. EXPECT FOG FORMATION ALONG AREA RIVERS AND LAKES WITH THIS
COOLER AIR ABOVE THE RELATIVELY WARMER WATER.
HIGH PRESSURE CENTERED OVER THE GREAT LAKES MONDAY WILL GRADUALLY
SHIFT SOUTHEAST AND RIDGE INTO OUR REGION. HIGH TEMPERATURES WILL
RANGE FROM THE LOWER 60S IN THE NORTHWEST MOUNTAINS TO THE LOWER
70S IN THE PIEDMONT.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
AS OF 345 PM EDT SUNDAY...
QUIET START TO THE WEEK WITH HIGH PRESSURE CENTERED TO OUR NORTH
AND A STALLED FRONTAL SYSTEM ALONG THE GULF COAST. THIS SHOULD
YIELD TRANQUIL WEATHER THROUGH AT LEAST TUESDAY NIGHT WITH NEAR
SEASONAL TEMPERATURES. MEANWHILE...AN UPPER LEVEL AREA OF LOW
PRESSURE...STRONG SHORT WAVE EXITING THE CENTRAL/SOUTHERN ROCKIES
SUNDAY...WILL MOVE TRANS-CONUS APPROACHING THE AREA TUESDAY
NIGHT...CROSSING THE AREA WEDNESDAY AND WEDNESDAY NIGHT.
CONFIDENCE IS INCREASING THIS WEATHER FEATURE WILL BE OUR NEXT
PRECIP GENERATOR...AND FAVOR RAISING POPS AND INCREASING
CLOUDINESS OVER THE AREA FOR MID WEEK. MODELS ARE TRENDING WETTER
AND ANOTHER MODEL RUN OR TWO WILL ADD CONFIDENCE TO THIS FORECAST.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 345 PM EDT SUNDAY...
UPPER LOW WILL EXIT THE REGION THURSDAY WITH DRY WEATHER RETURNING
FRIDAY AND INTO NEXT WEEKEND. HEIGHTS AND THICKNESSES INCREASE
POST PASSAGE OF THE UPPER LOW WHICH WILL RESULT IN WARMER TEMPS
FOR NEXT WEEKEND. LINGERING CLOUDINESS MAY HOLD TEMPERATURES DOWN
THURSDAY...BUT...RAISED TEMPS A DEGREE OR TWO EACH DAY FROM FRIDAY
THROUGH SUNDAY. NEXT OPPORTUNITY FOR SHOWERS WILL ENTER THE
PICTURE LATE SUNDAY INTO MONDAY WITH A FRONTAL PASSAGE FORECAST
FOR THE LAST DAY OF THE MONTH.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
AS OF 900 PM EDT SUNDAY...
SCT TO BKN VFR CIGS EXPECTED TO CONTINUE THROUGH THE EVENING AT
MOST SITES AS HIGH PRESSURE PUSHES IN FROM THE NORTH.
TONIGHT...MODELS SHOWING THAT POTENTIAL EXISTS FOR VFR CIGS TO
DEVELOP UNDER AN INVERSION IN THE EAST ACROSS THE ROA/LYH/DAN
AREA. THE NAM LOOKS TOO ROBUST WITH RETURN MOISTURE...WILL PLAY IT
ON DRIER SIDE.
LIGHT AND VARIABLE WINDS WILL PERSIST THROUGH THE NIGHT. THE
COMBINATION OF LIGHT WINDS AND LOW LEVEL MOISTURE WILL RESULT IN
AREAS OF FOG WITH THE BEST CHANCES AT LWB/BCB.
ASIDE FROM THE USUAL MORNING FOG IN BCB/LWB...VFR WX INTO
TUESDAY. THERE COULD BE SOME RAIN...AS WELL AS MVFR CEILINGS AND
VISIBILITIES STARTING WEDNESDAY OVER THE MTNS AS AN UPPER SYSTEM
MOVES ACROSS THE OHIO VALLEY...AND LOW LVL FLOW TURNS MORE SE.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...KK/PM
NEAR TERM...AMS/KK
SHORT TERM...PM
LONG TERM...PM
AVIATION...JC/KK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
633 PM CDT SUN SEP 22 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 209 PM CDT SUN SEP 22 2013
CURRENTLY AS OF 19Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A POTENT SHORTWAVE TROUGH OVER UTAH AND ARIZONA...WHILE
RIDGING WAS STRENGTHENING DOWNSTREAM FROM TEXAS INTO MINNESOTA. THE
FORECAST AREA LIES ON THE EAST SIDE OF THE RIDGE...FAVORING
SUBSIDENCE...DRY CONDITIONS AND HIGH PRESSURE. 12Z GRB...DVN AND MPX
SOUNDINGS HAD PRECIPITABLE WATER VALUES OF 0.4-0.65 INCHES...
ANYWHERE FROM 50-100 PERCENT OF NORMAL. THE DRY AIR HAS ALLOWED FOR
SUNNY SKIES ACROSS THE AREA. TEMPERATURES VARY GREATLY ACROSS THE
FORECAST AREA...RESULTING FROM 12Z 925MB TEMPS RANGING FROM 4C AT
GRB TO 11C AT MPX AND DVN. READINGS RANGE FROM THE UPPER 50S AT
MEDFORD TO LOW 70S IN FAR WESTERN PORTIONS OF THE FORECAST AREA.
WINDS ARE INCREASING JUST OFF TO THE WEST OVER THE PLAINS AND
MINNESOTA...AHEAD OF LEE TROUGHING. WARMER AIR IS ACCOMPANYING THE
STRONGER WINDS WITH 925MB TEMPS AT 12Z OF 16C AT ABR AND 20C AT OAX.
SYNOPTIC OVERVIEW...
THE POTENT SHORTWAVE TROUGH IN THE SOUTHWESTERN U.S. IS PROGGED TO
LIFT UP INTO SOUTH DAKOTA AND NEBRASKA BY 00Z TUESDAY. THE APPROACH
OF THE TROUGH WILL HELP STRENGTHEN AND AMPLIFY THE RIDGE AS IT
PUSHES EAST INTO MICHIGAN BY 00Z.
DETAILS...
DRY CONDITIONS ARE GOING TO CONTINUE DESPITE AN INCREASE OF
SOUTHERLY WINDS OVER THE NEXT 24 HOURS. IN FACT...THERE ARE
INDICATIONS THAT PRECIPITABLE WATER VALUES WILL EVEN FALL AS DRY AIR
CENTERED OVER THE OZARKS AREA GETS ADVECTED NORTH ON THE SOUTH
WINDS. THE INCREASING PRESSURE GRADIENT AND SOUTH WINDS OVER THE
AREA TONIGHT WILL LIMIT BOTH TEMPERATURE FALL AND VALLEY FOG
POTENTIAL TONIGHT. COLDEST READINGS ARE EXPECTED TOWARDS CENTRAL
WISCONSIN WHERE GRADIENT IS LIGHTEST...WITH LOWS IN THE UPPER 30S.
MAYBE SOME VALLEY FOG CAN FORM IN THE WISCONSIN RIVER VALLEY BECAUSE
OF THE WIND BEING ORTHAGONAL TO THE VALLEY. COMBINATION OF DRIER
AIR...925MB TEMPS RANGING FROM 12C EAST TO 15C WEST AT 18Z
MONDAY...AND SOUTHERLY BREEZE SHOULD ALLOW TEMPERATURES TO CLIMB
INTO THE UPPER 60S TO LOW 70S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 209 PM CDT SUN SEP 22 2013
FIRST ITEM OF INTEREST IS THE SHORTWAVE TROUGH OVER SOUTH DAKOTA AND
NEBRASKA ON MONDAY. MODELS ARE IN GOOD AGREEMENT OF THE TROUGH
WEAKENING AS IT GETS LIFTED TOWARDS THE FORECAST AREA ON
TUESDAY...IN RESPONSE TO RUNNING INTO THE RIDGING AHEAD OF IT. WITH
THE TROUGH WEAKENING...THE 850MB MOISTURE TRANSPORT ACCOMPANYING IT
ALSO BEGINS TO FALL APART. HOW QUICK THE WEAKENING OF THE TROUGH AND
ASSOCIATED 850MB MOISTURE TRANSPORT OCCURS WILL DETERMINE WHETHER
ANY PRECIPITATION GETS INTO THE FORECAST AREA. THE 22.12Z GFS
CONTINUES TO SUGGEST THE TROUGH WILL STILL BE STRONG ENOUGH TO BRING
SOME SHOWERS TUESDAY AFTERNOON AND EVENING TO LOCATIONS WEST OF THE
MS RIVER. MEANWHILE THE 22.12Z NAM/CANADIAN/UKMET AND 22.00Z/12Z
ECMWF ARE ALL DRY DUE TO THEM WEAKENING THE TROUGH AND MOISTURE
TRANSPORT QUICKER. MODEL CONSENSUS WOULD POINT TO A DRY
FORECAST...BUT HONORED THE GFS AND PREVIOUS FORECAST WITH 20 PERCENT
CHANCES WEST OF THE MS RIVER FOR TUESDAY AFTERNOON.
ANOTHER UPPER RIDGE IS FORECAST TO COME IN BEHIND THE TUESDAY TROUGH
BECAUSE OF A VERY DEEP TROUGH PROGGED TO FORM OVER THE WESTERN U.S.
ON WEDNESDAY. 500MB STANDARDIZED ANOMALIES OVER NEVADA AND
CALIFORNIA AT 00Z THU ARE 3 BELOW NORMAL. HEADING THROUGH THURSDAY
AND FRIDAY...THE TROUGH BEGINS TO LIFT OUT INTO THE NORTHERN
PLAINS...MOST LIKELY IN A POSITIVE TILT...CAUSING A HIGHLY AMPLIFIED
RIDGE TO DEVELOP OVER THE WESTERN GREAT LAKES REGION. SUBSIDENCE
WITH THIS RIDGE WILL KEEP THE FORECAST AREA DRY WEDNESDAY THROUGH
FRIDAY. EXPECT INCREASING SOUTHERLY WINDS AHEAD OF THE TROUGH TO
BRING WARMER AIR TO THE AREA AS WELL...WITH 925MB TEMPS PROGGED TO
CLIMB TO 14-17C ON WEDNESDAY AND THURSDAY...THEN TO 16-19C ON
FRIDAY. DPVA FORCING WITH THE TROUGH SHOULD APPROACH THE AREA FRIDAY
NIGHT...ALONG WITH A SURFACE COLD FRONT. ALL INDICATIONS ARE THAT
THE SOUTHERN PORTION OF THE TROUGH AND COLD FRONT WILL PASS THROUGH
THE FORECAST AREA EITHER SATURDAY OR SATURDAY NIGHT. ONCE THE TROUGH
AXIS PASSES...THE PRECIPITATION WILL END. PLAN ON A COOLER SATURDAY
DUE TO THE COMBINATION OF THE FRONTAL PASSAGE AND PRECIPITATION.
FOR SUNDAY AND EVEN HEADING INTO NEXT WEEK...GOOD MODEL CONTINUITY
EXISTS OF RIDGING STRENGTHENING ACROSS THE WESTERN U.S. AND INTO
SOUTHWEST CANADA. THIS WILL EVENTUALLY SET UP SOME TROUGHING
DOWNSTREAM OVER THE GREAT LAKES REGION. THE 22.12Z ECMWF IS VERY
QUICK AT DEVELOPING THIS TROUGHING...PHASING THE SOUTHERN PORTION OF
THE TROUGH ON SATURDAY WITH TROUGHING TRYING TO SET UP OVER THE
GREAT LAKES REGION. THE RESULT IS A WOUND UP LOW NEAR CHICAGO AT 12Z
SUNDAY. DO NOT HAVE MUCH CONFIDENCE OF THIS OCCURRING...BEING A
PHASING SCENARIO...THUS HAVE WENT WITH THE IDEA OF DRYING COMING IN
BEHIND THE SOUTHERN PORTION OF THE TROUGH. TEMPERATURES LOOK TO BE
JUST SLIGHTLY COOLER ON SUNDAY AS 925MB TEMPS FALL TO 10-13C.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 640 PM CDT SUN SEP 22 2013
AS UPPER RIDGE AXIS SHIFTS EAST...GRADIENT CONTINUES TO INCREASE SO
EXPECT BOUNDARY LAYER WINDS TO STAY UP COMPARED TO LAST NIGHT. WILL
HAVE TO WATCH SMALLER VALLEYS IN WISCONSIN AREAS FOR ANY PATCHY FOG
BUT VFR CONDITIONS SHOULD PREVAIL MOST EVERYWHERE UNDER DRY AIRMASS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...SHEA
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1047 AM CDT SAT SEP 21 2013
.UPDATE...
MID LEVEL TROUGH AXIS HAS SHIFTED EAST INTO MI/IN AS SURFACE HIGH
PRESSURE PUSHES IN BEHIND IT. LOW STRATUS HAVE MOVED IN FROM THE
NORTHWEST. EXPECT CLOUDY SKIES THROUGH MID AFTERNOON THEN CLEARING
FROM WEST TO EAST PER THE 13Z HRRR WHICH HAS PERFORMED WELL WITH
THE CURRENT TREND.
&&
.AVIATION/18Z TAFS/...
INITIAL CUMULUS DEVELOPMENT IS MVFR IN SPOTS THIS MORNING...BUT
DAYTIME MIXING WILL HELP TO RAISE CEILINGS TO VFR BY 18Z. CIGS
WILL LIKELY SCATTER BY LATE AFTERNOON...WITH MUCH LESS CLOUDS
EXPECTED TONIGHT INTO SUNDAY UNDER HIGH PRESSURE.
&&
.PREV DISCUSSION... /ISSUED 308 AM CDT SAT SEP 21 2013/
TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH.
SCATTERED CLOUDS THIS MORNING WITH LOWEST BASES AROUND THREE
THOUSAND FEET WILL CONTINUE TO LINGER OVER THE AREA THROUGH THE
AFTERNOON. HIGH PRESSURE WILL BUILD OVER THE AREA SATURDAY AND
WILL BE CENTERED OVER LAKE SUPERIOR SUNDAY MID-DAY.
FOR TONIGHT...HIGH PRESSURE WITH MOSTLY CLEAR SKIES AND LIGHT
WINDS WILL ALLOW TEMPERATURES TO RAPIDLY DROP TO MIDDLE 40S ALONG
LAKE MICHIGAN SHORELINE...TO UPPER 30S WELL INLAND. EXPECT PATCHY
FROST IN LOW-LYING AREAS SHORTLY BEFORE SUNRISE IN INLAND COUNTIES
NORTH AND WEST OF MADISON...AND ALSO IN THE WISCONSIN RIVER VALLEY.
SUNDAY THROUGH MONDAY NIGHT...FORECAST CONFIDENCE IS HIGH.
SHORT TERM MODELS IN GOOD AGREEMENT WITH FEATURES DURING THIS
TIME. HIGH PRESSURE SLIDES SOUTHEAST ACROSS THE WESTERN AND
CENTRAL GREAT LAKES REGION DURING THIS PERIOD. A 500MB RIDGE ALSO
MOVES EAST ACROSS THE REGION SUNDAY THROUGH MONDAY...WITH A
SHORTWAVE TROUGH MOVING INTO IOWA AND MINNESOTA MONDAY NIGHT.
QUIET WEATHER IS EXPECTED SUNDAY THROUGH MONDAY NIGHT.
FAVORABLE DELTA T VALUES WITH ONSHORE WINDS SUNDAY MAY BRING A FEW
CLOUDS...THOUGH MOISTURE IS MEAGER. THE SHORTWAVE TROUGH MONDAY
NIGHT IS POTENT...BUT THERE IS LITTLE IN THE WAY OF MOISTURE PER
AREA FORECAST SOUNDINGS.
925MB TEMPERATURE TRENDS SUGGEST HIGHS IN THE 60S SUNDAY AND
MONDAY...A BIT MILDER ON MONDAY WITH A SLIGHTLY WARMER AIRMASS.
LOWS MAY DROP INTO THE UPPER 30S IN LOW SPOTS SUNDAY NIGHT WITH
RADIATIONAL COOLING CONDITIONS...THOUGH MOST OF THE AREA WILL BE
IN THE 40S. MILDER MID TO UPPER 40S MONDAY NIGHT ARE EXPECTED WITH
CONTINUED WARM AIR ADVECTION PER GFS/ECMWF.
TUESDAY THROUGH FRIDAY...FORECAST CONFIDENCE IS MEDIUM.
GFS/ECMWF ARE SHOWING SOME DIFFERENCES DURING THIS PERIOD. THE GFS
BRINGS THE POTENT 500MB SHORTWAVE TROUGH THROUGH THE REGION
TUESDAY...WITH THE ECMWF DELAYING IT UNTIL TUESDAY NIGHT. BOTH
MODELS KEEP THE AREA DRY...AS AIRMASS REMAINS QUITE DRY PER AREA
FORECAST SOUNDINGS. NEAR NORMAL TEMPERATURES ARE EXPECTED.
500MB RIDGE CROSSES THE AREA WEDNESDAY...WITH FLOW BECOMING
SOUTHWESTERLY WEDNESDAY NIGHT INTO FRIDAY. HIGH PRESSURE TO THE
EAST OF THE AREA WILL KEEP DRY CONDITIONS GOING FOR WEDNESDAY INTO
THURSDAY. WARM AIR ADVECTION KICKING IN THURSDAY WILL BRING ABOVE
NORMAL TEMPERATURES INTO THE REGION.
GFS THEN BRINGS COLD FRONT EASTWARD INTO THE REGION THURSDAY
NIGHT AND FRIDAY...WITH THE ECMWF SLOWER AND KEEPING THE AREA DRY
DURING THIS TIME. GIVEN THE DIFFERENCES...WILL USE CONSENSUS POPS
AND TEMPERATURES FOR THURSDAY NIGHT INTO FRIDAY.
AVIATION/12Z TAFS/...
VFR CONDITIONS WITH LIGHT WINDS EXPECTED THROUGH THE WEEKEND.
MARINE...
LIGHT NORTHWEST WINDS TODAY BECOME NORTHEAST SUNDAY. WAVES AND
WINDS EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY LEVELS THROUGH
THE WEEKEND. MONDAY THROUGH THURSDAY...SOUTHERLY WINDS AND MOSTLY
SUNNY SKIES WITH NO SIGNIFICANT WEATHER OR SMALL CRAFT ADVISORY
CONDITIONS EXPECTED.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...SM/DDV
TODAY/TONIGHT AND AVIATION/MARINE...SLB
SUNDAY THROUGH FRIDAY...WOOD
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
503 AM EDT Mon Sep 23 2013
...Locally Heavy Rain Possible Through Mid Week...
.Near Term [Through Today]...
As was picked up well by the previous shift and the Hi-Res Models,
Convection with some heavy precip has begun to form early this
morning over the western FL Panhandle. Dual-Pol Radar estimates of
3-4.5" of rain have already fallen over Southeastern sections of
Walton county (mostly rural areas) in the last 6 hrs, so Urban and
Small Stream Flood Advisories should be sufficient at this point.
Although not much rain at all has fallen over Holmes and Washington
counties as of yet, this Meso-Low could help curl these heavier
precip bands off to the NNE and affect some of our most vulnerable
areas which have been hit quite hard earlier this summer with Flash
Flooding, so they certainly do not need the extra rainfall. The good
news, however, is that the highest PoPs and QPF are expected this
morning, as the Hi-Res WRFs and HRRR have been consistent in showing
a diminishing trend in the rainfall this afternoon. So clearly, the
greatest threat for flooding will be this morning. Also with all of
the extensive Cloud Cover and areas of rain, actually went with our
4 km WRF for both High, and hourly temperatures over the interior,
which only peak out in the upper 70s to lower 80s in most cases.
&&
.SHORT TERM [Tonight Through Wednesday]...
The unsettled weather pattern with a warm and moist airmass and
bouts of moderate to locally heavy rain will continue through the
period. Timing of heavy rain tricky given model differences and this
needs to be monitored to pinpoint forecasts. GFS and ECMWF seem to
have good model to model consistency and less aggressive than NAM
QPF and leaned towards GFS/ECMWF blending.
The large scale amplified pattern commences tonight with a deepening
trough over Cntrl Conus with low over NEB and axis Swd into TX. This
allows ridge to build briefly over Ern states including local
region. At the surface, low over Canadian Maritimes with cold front
Swd down extreme Wrn Atlc then Wwd becoming weaker and stationary
over FL coast or extreme Nrn Gulf of Mex waters connecting to low
around 100 miles south of Wrn LA Coast. Isentropic lift along and
north of boundary should provide enough lingering moisture and
low-level convergence for scattered showers and isolated
thunderstorms, especially near the coast and over the coastal
waters. Will go with 0-40% land and 40-60% marine N-S POP
gradient.
On Tuesday, as H5 shortwave moves out of Plains, Cntrl trough moves
Ewd reaching OH Valley by sundown shunting downstream ridge towards
Atlc. This added upper support will pick up LA low and help to
re-activate front. As a result, low begins to open up and track ENE
across Panhandle late. Aided by a few impulses moving SW-NE, the
front lifts back Nwd as a warm front with enhanced low level
convergence to around FL/AL/GA border. Area dew points rise to the
upper 60s Nrn counties to the low 70s Srn counties. This should
lead to another round of moderate to occasionally heavy rainfall
late into the night especially Wrn counties. Progressive movement
of upper and lower features suggest a limited flood threat but
given antecedent conditions, this will need to be monitored. Will
go with 70-40% SW-NE POP gradient daytime and 50-60% everywhere at
night.
On Wednesday, above shortwave reaches Lwr MS Valley before ejecting
EWD. This allows surface low to lifts ENE along warm front and
across our area during morning with highest POPs shifting to NE
tier counties. This will be our best shot for strong storms (see
below). With grounds likely saturated, the threat of flash
flooding remains elevated. Trough/low forecast to move east into
Atlc with trough axis along or just east of FL coast by sundown.
This should push the bulk of the forcing for precip off the east
coast as well. Thus, expect rainfall to taper off from west to
east during the day. Will go with 40-60% W-E POP gradient in
morning decreasing to 30-50% in the afternoon.
Although strong to severe storms are deemphasized, increasing shear
with advancing warm front plus shortwave may overcome weak instability,
weak lapse rates and warm H5 temperatures and generate gusty winds
and even a rotating cell or two especially when it interacts with
land mass and this needs to be monitored. With plenty of cloud
cover expected through midweek, we undercut GFS/NAM a few degrees.
With clouds and rain, expect high temperatures to hold in the mid
80s for most locations. Nights will be muggy. QPF for today
through Wednesday ranges from 1.5 to 2 inches over Florida and
0.60 to 1.5 inches over Georgia and Alabama. However locally
higher amounts are likely with periods of moderate to heavy rain
near frontal boundary.
&&
.LONG TERM [Wednesday Night through Sunday]...
For the latter half of the week, a significant ridge is forecast to
develop from the central Gulf Coast northward into the Ohio Valley.
At the surface, high pressure centered over New England will nose
down the eastern seaboard into the northeastern Gulf. This should
allow for a progressively cooler and drier airmass to push into the
region by late in the week, with noticeably cooler high temperatures
and pleasant morning lows.
&&
.Aviation...
[Through 12 UTC Tuesday] Conditions will be quite variable at the
terminals during the next 24 hours, with the greatest likelihood for
IFR or lower Cigs and Vis will at TLH, ECP, and VLD where the
highest PoPs and QPF are expected through the period. Currently only
expect VFR with possible MVFR conditions at ABY and DHN, but this
could change if the High Cloud Canopy Dissipates.
&&
.MARINE...
A frontal boundary south over the waters will weaken today. onshore
winds this morning will become easterly and increase slightly
tonight night as high pressure builds north of the waters. Weak low
pressure over Wrn Gulf today will pass NE and across the waters by
the middle of the week. At this time, winds are forecast to remain
below headline criteria but winds and seas will be high near any
showers and tstms.
&&
.Fire Weather...
Continued wet conditions will keep relative humidities very high for
the next several days.
&&
.HYDROLOGY...
Roughly 1 to 3 inches of rain has fallen across the region this
weekend, with the highest amounts close to the coast. Over the next
several days, another 1.5 to 2.5 inches will be possible with
locally higher amounts. This will be enough to generate minor rises
on area rivers. With the current forecast, widespread riverine
flooding appears unlikely. However, some localized flooding issues
may develop (especially in urban areas) if heavy rain can become
focused enough spatially and temporally.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 79 71 86 71 88 / 70 40 50 60 60
Panama City 82 74 85 73 86 / 70 40 60 60 50
Dothan 81 69 86 70 87 / 20 20 50 60 50
Albany 81 68 85 70 87 / 20 20 40 60 50
Valdosta 81 68 86 70 86 / 70 20 50 50 60
Cross City 85 70 86 72 88 / 70 40 60 50 60
Apalachicola 84 76 84 76 85 / 70 40 60 60 60
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...Gould
SHORT TERM...Block
LONG TERM...Camp
AVIATION...Gould
MARINE...Block
FIRE WEATHER...Gould
HYDROLOGY...Lamers/Block
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
456 AM EDT Mon Sep 23 2013
...Locally Heavy Possible Through Mid Week...
.Near Term [Through Today]...
As was picked up well by the previous shift and the Hi-Res Models,
Convection with some heavy precip has begun to form early this
morning over the western FL Panhandle. Dual-Pol Radar estimates of
3-4.5" of rain have already fallen over Southeastern sections of
Walton county (mostly rural areas) in the last 6 hrs, so Urban and
Small Stream Flood Advisories should be sufficient at this point.
Although not much rain at all has fallen over Holmes and Washington
counties as of yet, this Meso-Low could help curl these heavier
precip bands off to the NNE and affect some of our most vulnerable
areas which have been hit quite hard earlier this summer with Flash
Flooding, so they certainly do not need the extra rainfall. The good
news, however, is that the highest PoPs and QPF are expected this
morning, as the Hi-Res WRFs and HRRR have been consistent in showing
a diminishing trend in the rainfall this afternoon. So clearly, the
greatest threat for flooding will be this morning. Also with all of
the extensive Cloud Cover and areas of rain, actually went with our
4 km WRF for both High, and hourly temperatures over the interior,
which only peak out in the upper 70s to lower 80s in most cases.
&&
.SHORT TERM [Tonight Through Wednesday]...
The unsettled weather pattern with a warm and moist airmass and
bouts of moderate to locally heavy rain will continue through the
period. Timing of heavy rain tricky given model differences and this
needs to be monitored to pinpoint forecasts. GFS and ECMWF seem to
have good model to model consistency and less aggressive than NAM
QPF and leaned towards GFS/ECMWF blending.
The large scale amplified pattern commences tonight with a deepening
trough over Cntrl Conus with low over NEB and axis Swd into TX. This
allows ridge to build briefly over Ern states including local
region. At the surface, low over Canadian Maritimes with cold front
Swd down extreme Wrn Atlc then Wwd becoming weaker and stationary
over FL coast or extreme Nrn Gulf of Mex waters connecting to low
around 100 miles south of Wrn LA Coast. Isentropic lift along and
north of boundary should provide enough lingering moisture and
low-level convergence for scattered showers and isolated
thunderstorms, especially near the coast and over the coastal
waters. Will go with 0-40% land and 40-60% marine N-S POP
gradient.
On Tuesday, as H5 shortwave moves out of Plains, Cntrl trough moves
Ewd reaching OH Valley by sundown shunting downstream ridge towards
Atlc. This added upper support will pick up LA low and help to
re-activate front. As a result, low begins to open up and track ENE
across Panhandle late. Aided by a few impulses moving SW-NE, the
front lifts back Nwd as a warm front with enhanced low level
convergence to around FL/AL/GA border. Area dew points rise to the
upper 60s Nrn counties to the low 70s Srn counties. This should
lead to another round of moderate to occasionally heavy rainfall
late into the night especially Wrn counties. Progressive movement
of upper and lower features suggest a limited flood threat but
given antecedent conditions, this will need to be monitored. Will
go with 70-40% SW-NE POP gradient daytime and 50-60% everywhere at
night.
On Wednesday, above shortwave reaches Lwr MS Valley before ejecting
EWD. This allows surface low to lifts ENE along warm front and
across our area during morning with highest POPs shifting to NE
tier counties. This will be our best shot for strong storms (see
below). With grounds likely saturated, the threat of flash
flooding remains elevated. Trough/low forecast to move east into
Atlc with trough axis along or just east of FL coast by sundown.
This should push the bulk of the forcing for precip off the east
coast as well. Thus, expect rainfall to taper off from west to
east during the day. Will go with 40-60% W-E POP gradient in
morning decreasing to 30-50% in the afternoon.
Although strong to severe storms are deemphasized, increasing shear
with advancing warm front plus shortwave may overcome weak instability,
weak lapse rates and warm H5 temperatures and generate gusty winds
and even a rotating cell or two especially when it interacts with
land mass and this needs to be monitored. With plenty of cloud
cover expected through midweek, we undercut GFS/NAM a few degrees.
With clouds and rain, expect high temperatures to hold in the mid
80s for most locations. Nights will be muggy. QPF for today
through Wednesday ranges from 1.5 to 2 inches over Florida and
0.60 to 1.5 inches over Georgia and Alabama. However locally
higher amounts are likely with periods of moderate to heavy rain
near frontal boundary.
&&
.LONG TERM [Wednesday Night through Sunday]...
For the latter half of the week, a significant ridge is forecast to
develop from the central Gulf Coast northward into the Ohio Valley.
At the surface, high pressure centered over New England will nose
down the eastern seaboard into the northeastern Gulf. This should
allow for a progressively cooler and drier airmass to push into the
region by late in the week, with noticeably cooler high temperatures
and pleasant morning lows.
&&
.Aviation...
[Through 12 UTC Tuesday] Conditions will be quite variable at the
terminals during the next 24 hours, with the greatest likelihood for
IFR or lower Cigs and Vis will at TLH, ECP, and VLD where the
highest PoPs and QPF are expected through the period. Currently only
expect VFR with possible MVFR conditions at ABY and DHN, but this
could change if the High Cloud Canopy Dissipates.
&&
.MARINE...
A frontal boundary south over the waters will weaken today. onshore
winds this morning will become easterly and increase slightly
tonight night as high pressure builds north of the waters. Weak low
pressure over Wrn Gulf today will pass NE and across the waters by
the middle of the week. At this time, winds are forecast to remain
below headline criteria but winds and seas will be high near any
showers and tstms.
&&
.Fire Weather...
Continued wet conditions will keep relative humidities very high for
the next several days.
&&
.HYDROLOGY...
Roughly 1 to 3 inches of rain has fallen across the region this
weekend, with the highest amounts close to the coast. Over the next
several days, another 1.5 to 2.5 inches will be possible with
locally higher amounts. This will be enough to generate minor rises
on area rivers. With the current forecast, widespread riverine
flooding appears unlikely. However, some localized flooding issues
may develop (especially in urban areas) if heavy rain can become
focused enough spatially and temporally.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 79 71 86 71 88 / 70 40 50 60 60
Panama City 82 74 85 73 86 / 70 40 60 60 50
Dothan 81 69 86 70 87 / 20 20 50 60 50
Albany 81 68 85 70 87 / 20 20 40 60 50
Valdosta 81 68 86 70 86 / 70 20 50 50 60
Cross City 85 70 86 72 88 / 70 40 60 50 60
Apalachicola 84 76 84 76 85 / 70 40 60 60 60
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...Gould
SHORT TERM...Block
LONG TERM...Camp
AVIATION...Gould
MARINE...Block
FIRE WEATHER...Gould
HYDROLOGY...Lamers/Block
AREA FORECAST DISCUSSION
NWS TOPEKA KS
302 AM CDT Mon Sep 23 2013
.SHORT TERM...(Today and Tonight)
Issued at 302 AM CDT MON SEP 23 2013
Water vapor imagery as of 07z depicts the center of the strong upper
shortwave trough across southern Colorado shifting eastward.
Meanwhile an abundant amount of subsidence ahead of the wave was
noted. A frontal boundary stretched across the northern Gulf is
responsible in blocking moisture from spreading northward into the
region. At the surface, observations depict the surface trough
positioned across eastern Colorado with gusty southerly winds
stretching into western Kansas.
As the above mentioned upper wave lifts northeast into the central
plains Monday afternoon, the surface low edges into western Kansas,
gradually increasing southerly wind speeds between 20 and 25 mph
this afternoon. Gusts over 35 mph are expected as deeper mixing and
dry air aloft restrains dewpoints to the low 50s. Daytime heating
combined with convergence along and ahead of a weak cold front
shifting east may trigger scattered convection this afternoon and
evening. The recent runs of the HRRR and 4-KM ARW support this
thinking as north central areas stand to see the best chance of
precipitation. While speed shear is prevalent at 50 kts up to 6 Km,
uncertainty exists as to if the updrafts are able to maintain
themselves and reach the CWA border. Weak instability, mid level
lapse rates around 5-6 degrees C/Km, and meager moisture in place
can only warrant a slight chance mention of showers with perhaps an
isolated thunderstorm through this evening. The upper trough and
precipitation lifts out of the area overnight as the frontal
boundary and associated cloud cover passes through the area dry.
Expect highs today similar to previous afternoons with readings
generally in the upper 70s. By this evening, increasing insulation
from cloud cover and gusty southerly winds will boost low
temperatures a few degrees into the middle 50s.
.LONG TERM...(Tuesday through Sunday)
Issued at 302 AM CDT MON SEP 23 2013
Tuesday through Thursday continues to look dry as forcing from
upper trough moves east of the area and ridging develops. Models
show some weak cold air advection through part of the day
Tuesday. There is also better agreement on some higher 850MB RH
hanging in on the back side of the departing system implying skies
could be partly cloudy over eastern KS. Because of the cooler air
advecting south and east and the potential for a little more
clouds, have trended highs for Tuesday down a degree or two. By
Wednesday morning, skies could clear out with winds becoming light
and variable as a weak surface ridge axis passes over eastern KS
setting up conditions for good radiational cooling. Because of
this have also trended lows Wednesday morning down with some
readings potentially nearing 50. By Thursday the models are in
good agreement that southerly return flow will have begun with
better moisture advecting north. Therefore Highs in the 80s and
lows in the 60s appear reasonable.
For Thursday night through Saturday, the models remain in good
agreement with the overall synoptic pattern with only some slight
timing differences in the frontal passage. However it looks like
the most likely timing is for the front to move through late
Friday night and Saturday morning. If models continue to converge
on this solution, later shifts may want to increase pops to
likely as there appears to be plenty of moisture with modest
instability for the front to come through and lift. With the front
expected to remain north of the area most of the day Friday, temps
are expected to remain above normal with readings in the 80s.
Saturday looks to see the bulk of the cool down as cold air
advection increases through the day.
Precip should be all but over Saturday evening as the front is
progged to be into southeast KS and southern MO. Central and
eastern KS should see clearing skies into Sunday as a modified
pacific surface ridge builds into the plains and mid level heights
gradually rise. WPC tends to favor the more amplified pattern of
the ECMWF for the end of the weekend with a closed low eventually
developing to the east. This will likely keep Fall like temps for
the forecast area on Sunday.
&&
.AVIATION...(For the 06Z TAFs through 06Z Monday Night)
Issued at 1138 PM CDT SUN SEP 22 2013
Will keep current VFR forecast. May see a decrease in winds toward
the end of the forecast period and an outside chance for a VCTS
near MHK but too early to put in forecast.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...Bowen
LONG TERM...Wolters
AVIATION...67
AREA FORECAST DISCUSSION
NWS GAYLORD MI
302 AM EDT MON SEP 23 2013
.SYNOPSIS...
ISSUED AT 249 AM EDT MON SEP 23 2013
HIGH PRESSURE WILL BRING AN EXTENDED PERIOD OF DRY WEATHER AND
MOSTLY CLEAR SKIES THROUGH THE WORK WEEK. HIGH TEMPERATURES WILL
SLOWLY MODERATE...WITH READINGS WELL ABOVE NORMAL WEDNESDAY THROUGH
SATURDAY. OVERNIGHT LOWS WILL BE COOL...AND FROST REMAINS A
POSSIBILITY IN MANY AREAS AGAIN TONIGHT.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 249 AM EDT MON SEP 23 2013
LARGE CANADIAN HIGH PRESSURE SLIDES INTO THE EASTERN LAKES THROUGH
TONIGHT WITH DEVELOPING WEAK RETURN FLOW ACROSS NORTHERN
MICHIGAN. SENSIBLE WEATHER CONCERNS IN THE SHORT TERM FOCUSED
PRIMARILY ON CLOUD TRENDS AND MIN TEMPERATURES TONIGHT.
TODAY...LOW LEVEL FLOW VEERS SOUTHEAST ON WESTERN PERIPHERY OF HIGH
PRESSURE WITH STRENGTHENING WARM AIR ADVECTION PUSHING H8
TEMPERATURES INTO THE +7C TO +9C RANGE. BRINGING THESE TEMPS DOWN
DRY ADIABATICALLY YIELDS HIGHS IN THE UPPER 50S TO MID 60S
/WARMEST WEST/. TRICKY CLOUD FORECAST WITH PLENTY OF RESIDUAL LOW
LEVEL MOISTURE ALONG THE LAKE HURON COAST/SAGINAW BAY TRAPPED
BENEATH SUBSIDENCE INVERSION WITH FAVORABLE DELTA T/S AND WEAK
ONSHORE FLOW. THE RUC 925-850MB RH FIELDS SHOW THESE LOWER CLOUDS
PLAGUING LAKE HURON COASTAL AREAS FROM ALPENA SOUTHWARD TOWARD SAGINAW
BAY THROUGH THE MORNING HOURS. AS DELTA T/S DECREASE WITH WARMING
ALOFT AND MUCH DRIER AIR WORKS INTO THE AREA /PWATS AROUND
0.4/...THE CLOUDS SHOULD /HOPEFULLY/ DISSIPATE. AS IS FREQUENTLY
THE CASE THIS TIME OF YEAR WITH REGARD TO LOW CLOUDS...WOULD NOT
BE SURPRISED IF THEY ENDED UP MORE PERSISTENT THAN CURRENTLY
FORECAST.
TONIGHT...ANOTHER POTENTIAL FROSTY NIGHT FOR PORTIONS OF THE AREA.
EXCELLENT RADIATIONAL COOLING SCENARIO ONCE AGAIN WITH CLEAR SKIES
AND LIGHT WINDS. SEE LITTLE REASON WHY LOW TEMPS WILL NOT DIP INTO
THE MIDDLE 30S OVER PORTIONS OF NORTHERN LOWER /ESPECIALLY EAST OF
I-75/...WITH SOME READINGS LIKELY INTO THE LOWER 30S IN THE
TYPICALLY COLDER LOCATIONS. WILL "BEEF UP" THE FROST WORDING IN
THE HWO...BUT WILL LEAVE HEADLINE DECISIONS TO THE DAY SHIFT BASED
ON LATEST OBS/MODEL TRENDS. AREAS OF FOG ALSO LIKELY...PARTICULARLY
IN THE COLDER VALLEY LOCATIONS AND AROUND INLAND LAKES.
&&
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 249 AM EDT MON SEP 23 2013
A SPECTACULAR WORK WEEK IS AHEAD (HARD TO IMAGINE A MULTI-DAY
STRETCH WITH QUIETER LONG-TERM FORECASTS THAN THE LAST FEW). THE ONE
INCOMING SYSTEM OF ANY NOTE IS A VIGOROUS SHORTWAVE IN THE 4-CORNERS
REGION EARLY THIS MORNING. THIS SYSTEM WILL EMERGE INTO THE CENTRAL
PLAINS TODAY...BUT THEN ENCOUNTER A BLOCKED PATTERN TO THE EAST...
WITH A STALLED UPPER LOW OVER NEW BRUNSWICK AND RIDGING IN THE
LAKES. THE INCOMING WAVE/S SOLUTION TO THIS PROBLEM IS CUT
UNDERNEATH THE RIDGE...MOVING THRU THE OHIO VALLEY ON WEDNESDAY.
THAT WILL BE TOO FAR SOUTH TO HAVE MUCH IMPACT ON US. THAT LEAVES
TEMPS AS THE ONLY CONCERN OF NOTE.
TUESDAY INTO WEDNESDAY...500MB RIDGING...WHICH IS OVERHEAD TO START
TUE MORNING...WILL DRIFT EAST TO LAKE HURON THRU TUE NIGHT. AS THE
UPPER LOW PASSES TO OUR SOUTH...THAT RIDGE WILL BE DISRUPTED...BUT
RIDGING WILL BEGIN TO FOLD OVER TOP OF THE LOW AND POKE IN FROM THE
SW ON WEDNESDAY. AT THE SURFACE...HIGH PRESSURE WILL BE A SEMI-
PERMANENT FEATURE IN THE VICINITY OF LAKE HURON. THIS PERSISTENT
RIDGING SURFACE AND ALOFT WILL MAINTAIN DEEP SUBSIDENCE AND ABUNDANT
DRY AIR. 850-700MB RH LEVELS ARE BELOW 20 PERCENT THROUGHOUT...AND
ARE BELOW 10 PERCENT MOST OF THE TIME.
THE UPPER LOW PASSING TO OUR SOUTH WILL LIKELY FEED SOME THIN CIRRUS
OVERHEAD TUE NIGHT/WED. OTHERWISE...SKIES WILL BE CLEAR. MAX TEMPS
WILL BE MAINLY IN THE MID TO UPPER 60S BOTH DAYS...WITH A FEW 70S
POSSIBLE WEDNESDAY. MIN TEMPS 40-45 FOR MOST...BUT THE INLAND COOL
SPOTS WILL LOWER INTO THE MID/UPPER 30S.
REST OF THE FORECAST...500MB RIDGING GETS PUMPED BACK INTO THE
REGION FROM THE SW FOR THE REST OF THE WORK WEEK. THU/FRI LOOK VERY
PLEASANT AND MILD...WITH MAX TEMPS MAINLY IN THE 70S.
THE GFS REMAINS A FAST OUTLIER WHEN IT COMES TO BREAKING DOWN THE
RIDGE...AND USHERING IN OUR NEXT CHANCE FOR PRECIP. THE ECMWF HAS
BEEN MUCH MORE CONSISTENT...AND IS PREFERRED. HEIGHTS WILL BE
STEADILY ERODED THIS WEEKEND...WITH THE ACTUAL TROF AXIS ARRIVING
MOST LIKELY ON SUNDAY. THIS SUPPORTS DRY WX INTO FRIDAY NIGHT...AND
CHANCE POPS SAT THRU SUNDAY. SATURDAY WILL REMAIN WARM...WITH
READING CLOSER TO CLIMO SUNDAY.
THOUGH IT LIES BEYOND THE SCOPE OF THIS FORECAST...DIFFICULT TO TELL
HOW LONG THE UNSETTLED WX WILL LAST. 12Z ECMWF WANTED TO LINGER THE
TROF IN THE REGION LONG ENOUGH TO REINFORCE IT WITH ARCTIC
ENERGY...CARVING OUT AN UNPLEASANT UPPER LOW OVER THE LAKES REGION
NEXT WEEK. WE SHALL SEE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1245 AM EDT MON SEP 23 2013
HIGH PRESSURE WILL DRIFT SLOWLY TOWARD THE EASTERN GREAT LAKES
THROUGH MONDAY NIGHT. PATCHY FOG POSSIBLE AT ALL TERMINALS
OVERNIGHT...ALTHOUGH NOT WIDESPREAD ENOUGH TO WARRANT A MENTION IN
THE TAFS. AREAS OF 3-4K STRATO-CU OFF OF LAKE HURON MAY IMPACT APN
THROUGH MONDAY MORNING...WITH MAINLY SKC ELSEWHERE. LIGHT WINDS
THROUGHOUT THE PERIOD.
&&
.MARINE...
ISSUED AT 249 AM EDT MON SEP 23 2013
A LARGE AREA OF HIGH PRESSURE WILL ANCHORED ACROSS THE GREAT LAKES
FOR THE NEXT SEVERAL DAYS. WITH AN OVERALL LIGHT WIND REGIME...NO
HEADLINES ARE ANTICIPATED.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...FREEZE WARNING UNTIL 8 AM EDT THIS MORNING FOR MIZ016-017-022-
023-027>029-033>035-041.
FROST ADVISORY UNTIL 8 AM EDT THIS MORNING FOR MIZ008-015-018-
019-021-024>026-030>032-036-042.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
SYNOPSIS...JZ
SHORT TERM...JK
LONG TERM...JZ
AVIATION...JK
MARINE...JK
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1038 PM EDT SUN SEP 22 2013
.SYNOPSIS...
COLD NORTHWEST FLOW WILL MAKE FOR A PARTLY TO MOSTLY CLOUDY NIGHT.
OVERNIGHT LOWS WILL DROP INTO THE UPPER 30S TO LOWER 40S WITH
PATCHY FROST POSSIBLE IN THE WESTERN CATSKILLS OF NEW YORK. HIGH
PRESSURE WILL BUILD IN TOMORROW AND ALLOW AREAS OF FROST TO
DEVELOP ON TUESDAY MORNING. DRY WEATHER WILL BE IN PLACE INTO NEXT
WEEKEND WITH MODERATING TEMPERATURES.
&&
.NEAR TERM /THROUGH MONDAY/...
1030 PM UPDATE...CLOUDS PERSIST OVER THE REGION LATE THIS EVENING,
EVEN INTO THE WYOMING VALLEY. SKIES CLEARED BRIEFLY OVER LATE
ONTARIO BEFORE CLOUD STREETS DEVELOP WITH A NNW ORIENTATION
INDICATING A MOSTLY CLOUDY NIGHT FOR THE FINGER LAKES REGION, MUCH
OF THE SOUTHERN TIER AND NORTHERN TIER OF PA. SKIES WILL GRADUALLY
IMPROVE TO PARTY CLOUDY OVERNIGHT ACROSS THE WESTERN MOHAWK
VALLEY, WESTERN CATSKILLS AND POCONOS AS LOW LEVEL FLOW CONTINUES
TO VEER. BUMPED OVERNIGHT LOWS UP SLIGHTLY DUE TO INCREASED CLOUD
COVER. PATCHY FROST IS STILL POSSIBLE PRIMARILY IN THE WESTERN
CATSKILLS.
7 PM UPDATE...LATEST SATELLITE PICS SHOW STRATO CU HOLDING TUFF
ACROSS THE CWA. LATEST RAP SOUNDINGS SUGGEST MOSTLY CLOUDY SKIES
FOR MUCH OF THE FA OVERNIGHT WHILE THE NAM WOULD INDICATE SKIES
BECOMING PARTLY CLOUDY TO MAINLY CLEAR. LOW LEVEL FLOW IS EXPECTED
TO VEER OVERNIGHT TO A N/NNW DIRECTION. LAKE/T85 DIFFERENTIAL
ENOUGH TO SUPPORT LAKE CLOUDS, CURRENT THINKING IS MUCH OF THE AREA
WILL GRADUALLY BECOME PARTLY CLOUDY DURING THE EVENING WITH THE
MOST PERSISTENT CLOUDS ACROSS THE FINGER LAKES REGION INTO THE
CENTRAL SOUTHERN TIER DUE TO LOW LEVEL FLOW. ONLY ADJUSTMENT WAS
TO INCREASE CLOUD COVER INTO THE EARLY EVENING HOURS.
2 PM UPDATE...
LK EFFECT SHOWERS WL GRADUALLY WIND DOWN TONIGHT AS VORT MAX EXITS
THE CWA AND DRY AIR WORKS IN AFT MIDNIGHT. FAVORED LK REGIONS WL SEE
JUST ISOLD SHOWERS THRU ABOUT 03Z BFR DIMINISHING ALTOGETHER. CLOUDS
WL BEGIN TO VRY SLOWLY DECREASE AFT THIS TIME, ALLOWING TEMPS TO
FALL INTO THE 30S. CLDR VLY LOCATIONS IN THE CNTRL SRN TIER,
SUSQUEHANNA REGION AND THE WRN CATS MAY SEE PATCHY FROST TONIGHT AS
TEMPS PROGGED TO DROP TO 37F OR LWR. THAT IS, ASSUMING NO FOG DVLPS
TONIGHT. HV NOT ADDED IN PATCHY RVR VLY FOG TO THE GRIDS AT THIS
TIME AS WINDS SHUD STAY UP IN BL ARND 15KTS BUT CANNOT RULE OUT SOME
PATCHY DENSE FOG IN LOWEST VLY AREAS ARND ELMIRA AND SIDNEY. IF THAT
HAPPENS, PATCHY FROST WL BE INHIBITED IN THESE AREAS.
N-NW FLOW WL CONTINUE THRU THE DAY TOMORROW AS 1020MB HIPRES BEGINS
TO BUILD EAST. BL PROGGED TO DRY OUT AFT 18Z WITH MOSTLY-PARTLY SUNNY
SKIES EXPECTED THRU MRNG AS STRATOCU STARTS TO ERODE FM THE EDGES.
GFS H8 RH FIELDS EMULATING CLR SKIES UP NORTH OF LK SUPERIOR AT
PRESENT AND SLOWLY WORKS SOUTH AND EAST THRU 18Z MONDAY. HWVR, WL
NOT BE SO QUICK TO GO CLR DUE TO INFLUENCE OF LAKES AND WL KEEP
PCLDY CONDS THRU MID-MORNING THEN BEGIN CLRNG AFT 16Z AS UL RIDGE
BEGINS TO BUILD IN.
AFTN MAXES WILL TOP OUT ARND 60 ON MONDAY AND WITH MORE SUN EXPECTED
THAN TDA, WINDS SHUD GUST TO BTWN 15-20KTS DRG THE DAY.
&&
.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
2 PM UPDATE...
TEMPS ON MON NGT WL QUICKLY FALL OFF UNDER CLR SKIES AND LGT WINDS
DUE TO SFC HIPRES GETTING EVER CLOSER. OVRNGT LOWS EXPECTED TO DROP
TO ARND FRZG IN NOTORIOUSLY CLD LOCATIONS OF SRN TIER AND WRN CATS.
HV ALLOWED FOR PATCHY FROST IN AREAS THAT DROP TO 37F AND AREAS OF
FROST BLO 34F. WL PASS ON TO MIDNIGHT SHIFT ABOUT POSSIBLE FREEZE
WATCH FOR TUE MRNG AND WL CONTINUE TO HIGHLIGHT THREAT IN HWO.
HIPRES RMNS OVR THE AREA THRU THE END OF THE SHORT TERM WITH HIGHS
ON TUE EXPECTED TO CLIMB INTO THE 60S AND LOWS IN THE U30S/ARND 40.
AVG TEMPS DRG THIS TIME WL RUN SLIGHTLY BLO NORMAL DUE TO OVRNGT
LOWS.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
130 PM EDT UPDATE...
MINOR ADJUSTMENTS WERE MADE TO THE PREVIOUS FCST AS THE CURRENT
FORECAST APPEARS TO REMAIN DRY. FORECAST ON TRACK WITH STRONG SFC
HIGH BUILDING OVER THE REGION. AND THE NEXT CHANCE FOR SHOWERS AND
THUNDERSTORMS BEING ON SUNDAY WITH ANOTHER APPROACHING STORM
SYSTEM.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
WIDESPREAD STRATUS PREVAILING ACROSS THE REGION THIS EVENING AS
MOISTURE REMAINS TRAPPED BELOW A DEVELOPING SUBSIDENCE INVERSION.
BIG QUESTION IS WHEN AND IF THIS CLOUD LAYER BEGINS TO ERODE
OVERNIGHT. CURRENT THINKING IS THAT WE/LL SEE GRADUAL IMPROVEMENTS
AT SYR AND RME AS WIND FLOW BECOMES MORE NORTHERLY OVERNIGHT.
FURTHER SOUTH HOWEVER...FCST GUIDANCE SUGGESTING CLOUDS WILL HANG
TOUGH THROUGH A GOOD PORTION OF THE OVERNIGHT PERIOD...WITH
DEVELOPING RESTRICTIONS POSSIBLE AT ITH/BGM/AVP. FOR NOW...HAVE
KEPT A SUGGESTION OF LOW-END MVFR AT BOTH ITH AND BGM AFTER
06Z...HOWEVER OVERALL CONFIDENCE REMAINS MARGINAL AT THIS POINT.
SIMILAR TREND EXPECTED DOWN AT AVP WITH CIGS EXPECTED TO REMAIN
IN THE HIGH-END MVFR RANGE MAINLY AFTER 06Z.
MOVING INTO THE DAYLIGHT HRS...EXPECT A GRADUAL SCATTERING OUT AS
SUBSIDENCE INCREASES AND DRYING OCCURS ALOFT. WINDS WILL REMAIN
FROM THE NORTHWEST BETWEEN 8-12 KTS AT MOST LOCATIONS.
OUTLOOK...
MON NGT-FRI...MAINLY VFR. LATE NIGHT/EARLY MORNING VALLEY FOG
POSSIBLE ESPECIALLY KELM.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PVN
NEAR TERM...PVN/RRM
SHORT TERM...PVN
LONG TERM...CMG/KAH
AVIATION...CMG
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
810 PM EDT SUN SEP 22 2013
.SYNOPSIS...
LAKE EFFECT SHOWERS WILL DISSIPATE THIS EVENING. OVERNIGHT LOWS
WILL DROP INTO THE 30S AND MAY ALLOW PATCHY FROST TO DEVELOP IN
THE CENTRAL SOUTHERN TIER AND WESTERN CATSKILLS OF NEW YORK. HIGH
PRESSURE WILL BUILD IN TOMORROW AND ALLOW AREAS OF FROST TO
DEVELOP ON TUESDAY MORNING. DRY WEATHER WILL BE IN PLACE INTO NEXT
WEEKEND WITH MODERATING TEMPERATURES.
&&
.NEAR TERM /THROUGH MONDAY/...
7 PM UPDATE...LATEST SATELLITE PICS SHOW STRATO CU HOLDING TUFF
ACROSS THE CWA. LATEST RAP SOUNDINGS SUGGEST MOSTLY CLOUDY SKIES
FOR MUCH OF THE FA OVERNIGHT WHILE THE NAM WOULD INDICATE SKIES
BECOMING PARTLY CLOUDY TO MAINLY CLEAR. LOW LEVEL FLOW IS EXPECTED
TO VEER OVERNIGHT TO A N/NNW DIRECTION. LAKE/T85 DIFFERENTIAL
ENOUGH TO SUPPORT LAKE CLOUDS, CURRENT THINKING IS MUCH OF THE AREA
WILL GRADUALLY BECOME PARTLY CLOUDY DURING THE EVENING WITH THE
MOST PERSISTENT CLOUDS ACROSS THE FINGER LAKES REGION INTO THE
CENTRAL SOUTHERN TIER DUE TO LOW LEVEL FLOW. ONLY ADJUSTMENT WAS
TO INCREASE CLOUD COVER INTO THE EARLY EVENING HOURS.
2 PM UPDATE...
LK EFFECT SHOWERS WL GRADUALLY WIND DOWN TONIGHT AS VORT MAX EXITS
THE CWA AND DRY AIR WORKS IN AFT MIDNIGHT. FAVORED LK REGIONS WL SEE
JUST ISOLD SHOWERS THRU ABOUT 03Z BFR DIMINISHING ALTOGETHER. CLOUDS
WL BEGIN TO VRY SLOWLY DECREASE AFT THIS TIME, ALLOWING TEMPS TO
FALL INTO THE 30S. CLDR VLY LOCATIONS IN THE CNTRL SRN TIER,
SUSQUEHANNA REGION AND THE WRN CATS MAY SEE PATCHY FROST TONIGHT AS
TEMPS PROGGED TO DROP TO 37F OR LWR. THAT IS, ASSUMING NO FOG DVLPS
TONIGHT. HV NOT ADDED IN PATCHY RVR VLY FOG TO THE GRIDS AT THIS
TIME AS WINDS SHUD STAY UP IN BL ARND 15KTS BUT CANNOT RULE OUT SOME
PATCHY DENSE FOG IN LOWEST VLY AREAS ARND ELMIRA AND SIDNEY. IF THAT
HAPPENS, PATCHY FROST WL BE INHIBITED IN THESE AREAS.
N-NW FLOW WL CONTINUE THRU THE DAY TOMORROW AS 1020MB HIPRES BEGINS
TO BUILD EAST. BL PROGGED TO DRY OUT AFT 18Z WITH MOSTLY-PARTLY SUNNY
SKIES EXPECTED THRU MRNG AS STRATOCU STARTS TO ERODE FM THE EDGES.
GFS H8 RH FIELDS EMULATING CLR SKIES UP NORTH OF LK SUPERIOR AT
PRESENT AND SLOWLY WORKS SOUTH AND EAST THRU 18Z MONDAY. HWVR, WL
NOT BE SO QUICK TO GO CLR DUE TO INFLUENCE OF LAKES AND WL KEEP
PCLDY CONDS THRU MID-MORNING THEN BEGIN CLRNG AFT 16Z AS UL RIDGE
BEGINS TO BUILD IN.
AFTN MAXES WILL TOP OUT ARND 60 ON MONDAY AND WITH MORE SUN EXPECTED
THAN TDA, WINDS SHUD GUST TO BTWN 15-20KTS DRG THE DAY.
&&
.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
2 PM UPDATE...
TEMPS ON MON NGT WL QUICKLY FALL OFF UNDER CLR SKIES AND LGT WINDS
DUE TO SFC HIPRES GETTING EVER CLOSER. OVRNGT LOWS EXPECTED TO DROP
TO ARND FRZG IN NOTORIOUSLY CLD LOCATIONS OF SRN TIER AND WRN CATS.
HV ALLOWED FOR PATCHY FROST IN AREAS THAT DROP TO 37F AND AREAS OF
FROST BLO 34F. WL PASS ON TO MIDNIGHT SHIFT ABOUT POSSIBLE FREEZE
WATCH FOR TUE MRNG AND WL CONTINUE TO HIGHLIGHT THREAT IN HWO.
HIPRES RMNS OVR THE AREA THRU THE END OF THE SHORT TERM WITH HIGHS
ON TUE EXPECTED TO CLIMB INTO THE 60S AND LOWS IN THE U30S/ARND 40.
AVG TEMPS DRG THIS TIME WL RUN SLIGHTLY BLO NORMAL DUE TO OVRNGT
LOWS.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
130 PM EDT UPDATE...
MINOR ADJUSTMENTS WERE MADE TO THE PREVIOUS FCST AS THE CURRENT
FORECAST APPEARS TO REMAIN DRY. FORECAST ON TRACK WITH STRONG SFC
HIGH BUILDING OVER THE REGION. AND THE NEXT CHANCE FOR SHOWERS AND
THUNDERSTORMS BEING ON SUNDAY WITH ANOTHER APPROACHING STORM
SYSTEM.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
WIDESPREAD STRATUS PREVAILING ACROSS THE REGION THIS EVENING AS
MOISTURE REMAINS TRAPPED BELOW A DEVELOPING SUBSIDENCE INVERSION.
BIG QUESTION IS WHEN AND IF THIS CLOUD LAYER BEGINS TO ERODE
OVERNIGHT. CURRENT THINKING IS THAT WE/LL SEE GRADUAL IMPROVEMENTS
AT SYR AND RME AS WIND FLOW BECOMES MORE NORTHERLY OVERNIGHT.
FURTHER SOUTH HOWEVER...FCST GUIDANCE SUGGESTING CLOUDS WILL HANG
TOUGH THROUGH A GOOD PORTION OF THE OVERNIGHT PERIOD...WITH
DEVELOPING RESTRICTIONS POSSIBLE AT ITH/BGM/AVP. FOR NOW...HAVE
KEPT A SUGGESTION OF LOW-END MVFR AT BOTH ITH AND BGM AFTER
06Z...HOWEVER OVERALL CONFIDENCE REMAINS MARGINAL AT THIS POINT.
SIMILAR TREND EXPECTED DOWN AT AVP WITH CIGS EXPECTED TO REMAIN
IN THE HIGH-END MVFR RANGE MAINLY AFTER 06Z.
MOVING INTO THE DAYLIGHT HRS...EXPECT A GRADUAL SCATTERING OUT AS
SUBSIDENCE INCREASES AND DRYING OCCURS ALOFT. WINDS WILL REMAIN
FROM THE NORTHWEST BETWEEN 8-12 KTS AT MOST LOCATIONS.
OUTLOOK...
MON NGT-FRI...MAINLY VFR. LATE NIGHT/EARLY MORNING VALLEY FOG
POSSIBLE ESPECIALLY KELM.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PVN
NEAR TERM...PVN/RRM
SHORT TERM...PVN
LONG TERM...CMG/KAH
AVIATION...CMG
AREA FORECAST DISCUSSION
NWS BUFFALO NY
746 AM EDT SAT SEP 21 2013
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL CROSS OUR REGION TODAY AND BRING A
WIDESPREAD SOAKING RAINFALL. BEHIND THE FRONT...DRY WEATHER WILL
RETURN WITH TEMPERATURES FALLING BACK BELOW AVERAGE SUNDAY AND
MONDAY. AFTER THAT...DRY WEATHER SHOULD CONTINUE THROUGH MOST OF
NEXT WEEK...WITH TEMPERATURES WARMING BACK TO ABOVE AVERAGE
LEVELS.
&&
.NEAR TERM /THROUGH TONIGHT/...
DEEP LOW LEVEL THETA-E PLUME REMAINS FIRMLY IN PLACE JUST
UPSTREAM...LODGED WITHIN THE STEADY SOUTHWEST LOW LEVEL FLOW
ANCHORED IN ADVANCE OF THE COLD FRONT CURRENTLY WORKING THROUGH
EASTERN MICHIGAN/NORTHWEST OHIO. MOST RECENT HRRR AND SPC SSEO
OUTPUT SUGGESTING A GRADUAL EASTWARD SHIFT TO THE SOLID BAND OF
SHOWERS FOCUSED AHEAD OF THE COLD FRONT INTO THE REGION BEFORE
SUNRISE IN THE FAR WEST AND THE REMAINDER OF THE AREA THROUGH THE
DAY TODAY. THIS SUGGESTION LOOKS REASONABLE AS STRONGER LOW-MID
LEVEL ASCENT ATTRIBUTED TO FRONTAL CONVERGENCE...FAVORABLE EXIT
REGION JET DYNAMICS...AND THE ARRIVAL OF THE BETTER HEIGHTS
ATTENDANT WITH THE PV ANOMALY EJECTING ACROSS GREAT LAKES WILL WORK
ACROSS WESTERN AND NORTH CENTRAL NEW YORK THROUGH AT LEAST THE FIRST
HALF OF THE DAY. IMPRESSIVE MOISTURE QUALITY WORKING INTO THE REGION
WILL LEAD TO THE POTENTIAL FOR A STEADY MODERATE TO HEAVY RAINFALL
EVENT WITH MOST MODEL CONSENSUS SUGGESTING AMOUNTS EXCEEDING AN INCH.
THESE AMOUNTS MAY BE ENOUGH TO BRING SOME LOCALIZED FLOOD
PROBLEMS...BUT LIKELY NOT ENOUGH TO CAUSE SIGNIFICANT ISSUES WITH
LOCAL RIVERS AND CREEKS. THE POTENTIAL FOR THUNDER APPEARS LESS
FAVORABLE WITH VERY POOR INSTABILITY PARAMETERS THEREFORE WILL
DOWNPLAY THE POTENTIAL WITH ONLY THE SUGGESTION OF ISOLATED COVERAGE.
POST FRONTAL COLD/DRY ADVECTION RAMPS UP IN WAKE OF FRONT TONIGHT...
WITH MODELS AGREEING ON 850 MB TEMPERATURES FALLING TO 2-4C IN
DEEPENING NORTHWEST FLOW REGIME. COULD SEE A PERIOD OF CLEARING...BUT
EXPECT A BKN/OVC STRATOCUMULUS CLOUD DECK TO SETTLE IN FOR MUCH OF
THE NIGHT GIVEN CYCLONIC FLOW AND MOISTURE FLUX OFF THE LAKES PER
LAKE-850 MB TEMPERATURE DIFFERENTIALS. CANNOT RULE A FEW
INSTABILITY/LAKE EFFECT SHOWERS AS COLD POCKET ALOFT PIVOTS
THROUGH THE LOWER LAKES.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
SURFACE COLD FRONT WILL BE WELL EAST OF THE REGION ON SUNDAY
MORNING...BUT MOISTURE LINGERING BEHIND THE FRONT WILL ENCOUNTER AN
UPSLOPE NORTHWESTERLY WIND AND WILL LIKELY FORM AN INLAND CLOUD DECK
DURING A LARGE PART OF SUNDAY. THE COLDER CORE OF THE UPPER
TROUGH/LOW WILL BE FAR ENOUGH TO THE NORTH TO LIMIT THE MID LEVEL
INSTABILITY DURING SUNDAY AFTERNOON...BUT COLDER BOUNDARY LAYER
TEMPS WILL PUT QUITE A CHILL IN THE AIR FOR THE DAYTIME WITH HIGH
TEMPS ONLY IN THE MID TO UPPER 50S.
CONTINUED INFLUX OF DRIER AIR ALOFT WILL RESULT IN A CLEARING TREND
FOR SUNDAY NIGHT WITH COLD ADVECTION AND PRIME RADIATIONAL COOLING
DROPPING OVERNIGHT TEMPS TO THE UPPER 30S TO LOWER 40S. EXPECT
VALLEY FOG ACROSS THE SOUTHERN TIER AND PATCHY FROST ACROSS THE
HILLTOPS OF THE SOUTHERN TIER AND WESTERN ADIRONDACKS.
COOL HIGH PRESSURE CENTERED OVER ONTARIO AND WESTERN QUEBEC WILL
MAINTAIN A COOL INFLUX OF DRY AIR DURING THE BEGINNING OF THE
WORKWEEK. SUNSHINE WILL ABOUND ON MONDAY BUT COOL AIR WILL HOLD HIGH
TEMPS TO THE MID TO UPPER 50S ONCE AGAIN. OVERNIGHT LOWS WILL BE A
SHADE LESS CHILLY ON MONDAY NIGHT AS THE AIRMASS MODIFIES SLOWLY
OVER TIME. LOW TEMPS WILL BE IN THE UPPER 30S TO LOWER 40S ONCE
AGAIN...AND STILL THAT CHANCE FOR FROST PATCHES ON THE EXPOSED
HILLTOPS.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AN EXTENDED PERIOD OF QUIET WEATHER WILL BE IN PLACE FOR MUCH OF
NEXT WEEK COURTESY OF HIGH PRESSURE EXTENDED FROM THE OHIO VALLEY
INTO NEW ENGLAND. TUESDAY AND WEDNESDAY TEMPERATURES WILL CLIMB BACK
TO NORMAL LATE SEPTEMBER LEVELS. MODELS SHOW A RETURN OF WARM AIR
FOR THURSDAY AND FRIDAY AS THE SURFACE HIGH CENTERED ALONG THE EAST
COAST. HIGHS WILL RUN IN THE 70S AGAIN THURSDAY AND FRIDAY WITH OUR
NEXT CHANCE FOR RAIN LIKELY HOLDING OFF UNTIL NEXT WEEKEND.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
A SLOW MOVING COLD FRONT WILL CROSS THE REGION TODAY. A BAND OF
SHOWERS WILL WORK EASTWARD ACROSS THE REGION THROUGH THISAFTERNOON.
WIDESPREAD IFR CONDITIONS ASSOCIATED WITH THIS BAND. EMBEDDED
THUNDER IS LOOKING LESS LIKELY WITH ALL MENTION OF THUNDER REMOVED
FROM THE TAFS.
THIS MORNING...A BRIEF PERIOD OF LOW LEVEL WIND SHEAR WILL ALSO BE
POSSIBLE AT KART AS A 40+ KT LOW LEVEL JET SLIDES EAST IN ADVANCE
OF THE APPROACHING FRONT.
IMPROVING CONDITIONS WILL OCCUR BEHIND THE FRONT WITH JIAG/KBUF/KROC
BECOMING VFR BY LATE AFTERNOON...BUT NOT UNTIL LATE EVENING AT
KART AND KJHW.
OUTLOOK...
SUNDAY THROUGH WEDNESDAY...VFR.
&&
.MARINE...
A COLD FRONT WILL PUSH ACROSS THE CENTRAL AND EASTERN GREAT LAKES
TODAY WITH WAVES INCREASING ON THE EASTERN ENDS OF BOTH LAKES ERIE
AND ONTARIO. ADVISORY LEVEL WINDS AND WAVES WILL CONTINUE
ACROSS THE EAST END OF LAKE ONTARIO AS THE FRONT APPROACHES.
EXPECT THE WINDS TO SHIFT TO NORTHWESTERLY FOLLOWING THE FRONTAL
PASSAGE TONIGHT. ADVISORY CRITERIA MAY DEVELOP ALONG THE SOUTH SHORE
OF LAKE ONTARIO LATE TONIGHT AND SUNDAY MORNING.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR LOZ045.
&&
$$
SYNOPSIS...TMA
NEAR TERM...TMA
SHORT TERM...WCH
LONG TERM...SMITH
AVIATION...TMA
MARINE...TMA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
143 AM EDT MON SEP 23 2013
.SYNOPSIS...
COOL CANADIAN HIGH PRESSURE WILL BUILD EAST ACROSS THE GREAT LAKES
THROUGH MONDAY. THIS HIGH WILL REMAIN IN THE GREAT LAKES VICINITY
THROUGH MOST OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
THE GREAT LAKES REGION REMAINS BETWEEN AN UPPER LEVEL TROUGH OVER
QUEBEC AND A RIDGE BUILDING OVER THE UPPER MIDWEST. ENOUGH
TROUGHINESS REMAINS ALONG WITH THE 850MB COLD POOL(TEMPS DOWN TO -2C
OVER ONTARIO) TO MAINTAIN CONSIDERABLE CLOUD COVER DOWNWIND OF THE
LAKE. AS NOTED EARLY...NAM SOUNDINGS ARE ALREADY RUNNING A LITTLE
TOO OPTIMISTIC WITH CLEARING WHILE RUC SOUNDINGS KEEP EASTERN
AREAS CLOUDY ALL NIGHT BENEATH THE LOWERING INVERSION. HRRR IS
SIMILAR...HINTING AT SOME BREAKS BUT NOT COMPLETELY CLEARING.
WILL CARRY A MOSTLY CLEAR FORECAST TOWARDS FINDLAY WITH MOSTLY
CLOUDY SKIES FOR MOST OF THE NIGHT ACROSS THE EASTERN HALF OF THE
AREA. HAVE ADJUSTED THE HOURLY SKY GRIDS...MERGING THE FORECAST
WITH THE LATEST GUIDANCE. MOS GUIDANCE ALSO TOO QUICK WITH THE
CLEARING TREND SO WILL GO 2-5 DEGREES WARMER TONIGHT FOR AREAS
EAST OF A CLE-CAK LINE. THIS STILL SEEMS TO BE REASONABLE. ONLY
MADE ADJUSTMENTS TO SOME HOURLY TEMPERATURES. TEMPERATURES WILL
FALL QUICKLY WITH ANY SIZABLE BREAKS IN THE CLOUDS. MAY STILL HAVE
A SPRINKLE OR TWO FOR A LITTLE WHILE THIS EVENING FROM THE STRATUS
DECK.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
A DRY STRETCH OF WEATHER WITH COOL NIGHTS TO FOLLOW DURING THE SHORT
TERM. HIGH PRESSURE WILL REMAIN OVER THE EASTERN GREAT LAKES THROUGH
TUESDAY...SHIFTING SLIGHTLY TO THE NORTH ON WEDNESDAY. DIURNAL CU
EXPECTED ONCE AGAIN ON MONDAY BEFORE WE FINALLY MIX OUT OUR MOISTURE
AND CLEAR FOR MONDAY NIGHT. THIS WILL SET UP FOR A CHILLY NIGHT ON
MONDAY WITH MOST INLAND AREAS DIPPING TO NEAR 40 DEGREES. SOME OF
THE COOLER SPOTS IN NE OHIO WILL DIP INTO THE UPPER 30S WITH MID 30S
FOR INTERIOR NW PA. HAVE INCLUDED AREAS OF FROST FOR THOSE COOLEST
SPOTS AND THERE IS POTENTIAL THAT WE MAY NEED A FROST ADVISORY FOR
ERIE AND CRAWFORD PA. A HEALTHY DIURNAL SPREAD WILL ALLOW HIGHS TO
RECOVER INTO THE LOW AND MID 60S FOR TUESDAY...THEN COOL BACK INTO
THE 40S FOR TUESDAY NIGHT. LEANED THE FORECAST TOWARDS THE RAW MODEL
TEMPERATURES WHICH ARE SLIGHTLY COOLER THAN MOS GUIDANCE THROUGH THE
SHORT TERM.
UPPER LEVEL LOW OVER THE GREAT BASIN WILL MOVE NORTHEAST ACROSS THE
PLAINS ON MONDAY AND ENCOUNTER SOME RESISTANCE BY THE HIGH AMPLITUDE
UPPER LEVEL RIDGE OVER THE GREAT LAKES REGION. THE UPPER LOW WILL
WEAKEN AS IT SLIDES EAST ACROSS THE OHIO VALLEY ON TUESDAY NIGHT AND
WEDNESDAY. MODELS KEEP THE QPF SOUTH OF THE FORECAST AREA AND GIVEN
THE RESIDENT DRY AIR MASS IN PLACE...WILL KEEP THE FORECAST DRY WITH
JUST SOME INCREASE IN CLOUDS ON WEDNESDAY. TEMPS WILL RETURN TO NEAR
70 MOST AREAS.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
A RIDGE OF HIGH PRESSURE WILL BE OVER THE AREA TO START THE FORECAST
PERIOD AND THEN IT WILL SHIFT SLOWLY EAST AS A WEAKENING COLD FRONT
ADVANCES TOWARDS THE REGION. SOME QUESTION AS TO THE TIMING OF THE
FRONT FOR LATE IN THE WEEKEND. THE 12Z GFS IS MUCH QUICKER THAN THE
ECMWF AND THE CANADIAN MODEL. AT THIS TIME LEANING MORE TOWARD THE
SLOWER MODELS. SO THE MAIN CHANCE OF PRECIPITATION WILL BE ON SUNDAY
INTO SUNDAY NIGHT. IT SEEMS STABLE SO ONLY FORECASTING SHOWERS. USED
A BLEND OF GUIDANCE FOR THE NEAR NORMAL TEMPERATURES.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
THERE WILL BE A FEW PATCHES OF MVFR CEILINGS THIS MORNING AS LOW
LEVEL MOISTURE REMAINS TRAPPED BELOW THE SUBSIDENCE INVERSION. IT
WILL TAKE A WHILE TO MIX AWAY THE 035-045BKN/OVC STRATOCUMULUS
OVER THE EASTERN GREAT LAKES. THE CEILINGS WILL EXPAND INTO KTOL
AND KFDY THIS MORNING. CEILINGS WILL SCATTER OUT BY MID TO LATE
AFTERNOON... THEN CLEAR SKIES TONIGHT WITH THE FLOW VEERING FROM
NE TO LIGHT EASTERLY.
OUTLOOK...VFR.
&&
.MARINE...
A RIDGE OF HIGH PRESSURE WILL BE BUILDING IN TONIGHT. WILL LET THE
SMALL CRAFT ADVISORY AND RIP CURRENT RISK EXPIRE/CANCEL AS THE WINDS
AND WAVES ARE DECREASING. HOWEVER AS THE RIDGE IS BUILDING IN
TONIGHT THE NORTHEAST FLOW GRADIENT WILL INCREASE AND THAT COULD
CAUSE THE WAVES TO GET CLOSE TO SMALL CRAFT ADVISORY CRITERIA AND
AGAIN ON MONDAY. HOWEVER...AT THIS TIME IT SEEMS THAT 2 TO 4 FOOT
WAVES SHOULD HANDLE IT. AS THE RIDGE BECOMES STRONGER MONDAY NIGHT
AND TUESDAY THE WINDS WILL BE LIGHTER...THUS DECREASING THE WAVES.
THE RIDGE WILL BE AROUND THE LAKE THROUGH FRIDAY AND THAT WILL MEAN
AN EAST OR NORTHEAST FLOW. AT THIS TIME A SMALL CRAFT ADVISORY IS
NOT EXPECTED AS THE NORTHEAST FLOW SHOULD NOT BE STRONG ENOUGH TO
CAUSE 3 TO 5 FOOT WAVES BUT THIS WILL HAVE TO BE WATCHED AS
NORTHEAST FLOWS ARE NOTORIOUS FOR CAUSING HIGH WAVES ESPECIALLY ON
THE WEST END OF THE LAKE BECAUSE OF THE LONG FETCH.
A COLD FRONT WILL BE APPROACHING THE LAKE FOR LATE IN THE UPCOMING
WEEKEND SHIFTING THE WINDS TO SOUTHERLY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KEC
NEAR TERM...KEC/OUDEMAN
SHORT TERM...KEC
LONG TERM...KIELTYKA
AVIATION...KOSARIK
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
329 AM CDT MON SEP 23 2013
.SHORT TERM...TODAY THROUGH WEDNESDAY
WATER VAPOR IMAGERY SHOWS THE UPPER LOW OVER COLORADO EARLY THIS
MORNING. AT THE SURFACE...FRONTAL BOUNDARY IS LOCATED ACROSS
WESTERN SOUTH DAKOTA. SCATTERED SHOWERS HAVE BEEN OCCURRING ACROSS
WESTERN SOUTH DAKOTA AND OVER THE EXTREME NORTHWEST CWA OVER THE
PAST SEVERAL HOURS...BUT RADAR RETURNS ARE DIMINISHING AT THIS
TIME. AHEAD OF THE FRONT...BREEZY/GUSTY SOUTHERLY WINDS CONTINUE
OVER MUCH OF THE CWA WITH TEMPS STILL VERY MILD.
AS THE UPPER LOW KICKS OUT INTO THE PLAINS LATER THIS MORNING...A
REGENERATION OF SHOWERS AND STORMS IS EXPECTED OVER THE WESTERN
DAKOTAS. THE LATEST RUN OF THE HRRR AND THE 00Z NSSL WRF SHOW
WESTERN SOUTH DAKOTA SEEING THE BULK OF THE ACTIVITY THROUGH THE
MORNING HOURS...WITH CENTRAL SOUTH DAKOTA HOLDING OFF UNTIL THE
AFTERNOON. WILL HAVE TO WAIT FOR THE UPPER LOW TO GET CLOSER TO
THE AREA IT APPEARS FOR RAINFALL CHANCES TO INCREASE. 00Z NSSL WRF
INDICATES SHOWER AND THUNDERSTORM ACTIVITY DEVELOPING BETWEEN THE
MISSOURI AND JAMES RIVERS BY AROUND 21Z. ALL MODELS INDICATING
THAT THIS SYSTEM WILL WEAKEN AS IT CONTINUES MOVING EAST...WITH
BAND OF RAINFALL DISSIPATING AND BECOMING MORE WIDELY SCATTERED AS
IT MOVES EAST OF THE JAMES VALLEY. HAVE CONSTRUCTED WX/POP GRIDS
TO REFLECT THIS THINKING AND KEPT HIGHEST POPS OVER THE WESTERN
CWA THROUGHOUT THE DAY.
WITH THE SLOWER MOVEMENT OF THE UPPER LOW AND SURFACE FRONT...HAVE
INCREASED HIGHS A COUPLE DEGREES OVER THE EASTERN CWA WHERE
SOUTHERLY WINDS WILL REMAIN AND 850MB TEMPS STAY THE WARMEST.
SPEAKING OF WINDS...EXPECT ANOTHER WINDY DAY FOR THE EASTERN
COUNTIES...BUT LIKELY STAYING BELOW ADVISORY LEVELS.
TUESDAY AND TUESDAY NIGHT WILL BE QUIET AS A WEAK SURFACE RIDGE
SLIDES EAST OVER THE AREA. LOOK FOR MILD TEMPS AND DRY CONDITIONS.
WINDS BEGIN TO INCREASE AGAIN BY WEDNESDAY AS ANOTHER LOW PRESSURE
SYSTEM DEVELOPS TO THE WEST OF THE REGION.
.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY
MAIN FCST CHALLENGE FACING THE EXTENDED PORTION OF FORECAST
REVOLVES AROUND PCPN CHANCES HEADING INTO THE WEEKEND...AND TEMPS
FOR NEXT WEEKEND.
MODELS CONT TO ADVERTISE A LONG WAVE TROF MOVING INTO THE INTERMTN
STATES TO BEGIN THE EXTENDED FOR THE WEDNESDAY NIGHT PERIOD. GOOD
MID LEVEL WAA AHEAD OF THIS TROF AS INDICATED BY 700HPA THETA-E
FORCING. HOWEVER...BOTH GFS AND LATEST EC SUGGEST SFC WINDS WILL
BE MORE SERLY WHICH TYPICALLY ISN`T A GOOD WARMING WIND FOR THE
CWA. THIS WILL PROBABLY HELP TO TEMPER HIGHS SOMEWHAT FROM WHAT
THEY COULD BE GIVEN A SOUTH OR EVEN SW WIND. THE EC IS A BIT
SLOWER THAN GFS ON ARRIVAL OF PCPN...WAITING UNTIL CLOSER TO 12Z
FRIDAY FOR ONSET. THAT SAID...SINCE STILL LOOKING AT 5 DAYS
OUT...AM CONTENT TO LEAVE ALLBLEND GRID ALONE AND REFINE AS
SHORTER TERM MODELS BEGIN TO COVER THIS TIME FRAME.
WITH COLD FROPA DURING THE DAY FRIDAY WITH PLENTY OF EXPECTED
CLOUD COVER...COOLISH TEMPS FRIDAY/SATURDAY SEEM
REALISTIC...ESPECIALLY WITH BOTH GFS AND EC SHOWING 850HPA TEMPS
IN THE +4C TO +6C RANGE. WAA RETURNS IN EARNEST FOR SUNDAY..SO
FORECAST HIGHS ABOUT A CATEGORY WARMER THAN SATURDAY ALSO SEEMS
PLAUSIBLE.
&&
.AVIATION...
06Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
A FEW SHOWERS AND THUNDERSTORMS ARE POSSIBLE WEST OF THE MISSOURI
RIVER DURING THE OVERNIGHT HOURS. NO SEVERE WEATHER IS EXPECTED
AND NO TAF SITES ARE EXPECTED TO BE AFFECTED. THE WESTERN HALF OF
THE CWA WILL SEE A CHANCE FOR RAIN SHOWERS AGAIN DURING THE
LATE AFTERNOON AND EVENING HOURS ON MONDAY. SOUTHERLY WINDS WILL
REMAIN IN THE 15 TO 30 MPH RANGE. CIGS AND VSYBS WILL GENERALLY
REMAIN IN THE VFR CATEGORY...BUT COULD DROP A BIT LOWER WITH ANY
HEAVIER SHOWERS THAT MAY DEVELOP MONDAY EVENING.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
SHORT TERM...TMT
LONG TERM...HINTZ
AVIATION...HINTZ
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1120 PM CDT SUN SEP 22 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 209 PM CDT SUN SEP 22 2013
CURRENTLY AS OF 19Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A POTENT SHORTWAVE TROUGH OVER UTAH AND ARIZONA...WHILE
RIDGING WAS STRENGTHENING DOWNSTREAM FROM TEXAS INTO MINNESOTA. THE
FORECAST AREA LIES ON THE EAST SIDE OF THE RIDGE...FAVORING
SUBSIDENCE...DRY CONDITIONS AND HIGH PRESSURE. 12Z GRB...DVN AND MPX
SOUNDINGS HAD PRECIPITABLE WATER VALUES OF 0.4-0.65 INCHES...
ANYWHERE FROM 50-100 PERCENT OF NORMAL. THE DRY AIR HAS ALLOWED FOR
SUNNY SKIES ACROSS THE AREA. TEMPERATURES VARY GREATLY ACROSS THE
FORECAST AREA...RESULTING FROM 12Z 925MB TEMPS RANGING FROM 4C AT
GRB TO 11C AT MPX AND DVN. READINGS RANGE FROM THE UPPER 50S AT
MEDFORD TO LOW 70S IN FAR WESTERN PORTIONS OF THE FORECAST AREA.
WINDS ARE INCREASING JUST OFF TO THE WEST OVER THE PLAINS AND
MINNESOTA...AHEAD OF LEE TROUGHING. WARMER AIR IS ACCOMPANYING THE
STRONGER WINDS WITH 925MB TEMPS AT 12Z OF 16C AT ABR AND 20C AT OAX.
SYNOPTIC OVERVIEW...
THE POTENT SHORTWAVE TROUGH IN THE SOUTHWESTERN U.S. IS PROGGED TO
LIFT UP INTO SOUTH DAKOTA AND NEBRASKA BY 00Z TUESDAY. THE APPROACH
OF THE TROUGH WILL HELP STRENGTHEN AND AMPLIFY THE RIDGE AS IT
PUSHES EAST INTO MICHIGAN BY 00Z.
DETAILS...
DRY CONDITIONS ARE GOING TO CONTINUE DESPITE AN INCREASE OF
SOUTHERLY WINDS OVER THE NEXT 24 HOURS. IN FACT...THERE ARE
INDICATIONS THAT PRECIPITABLE WATER VALUES WILL EVEN FALL AS DRY AIR
CENTERED OVER THE OZARKS AREA GETS ADVECTED NORTH ON THE SOUTH
WINDS. THE INCREASING PRESSURE GRADIENT AND SOUTH WINDS OVER THE
AREA TONIGHT WILL LIMIT BOTH TEMPERATURE FALL AND VALLEY FOG
POTENTIAL TONIGHT. COLDEST READINGS ARE EXPECTED TOWARDS CENTRAL
WISCONSIN WHERE GRADIENT IS LIGHTEST...WITH LOWS IN THE UPPER 30S.
MAYBE SOME VALLEY FOG CAN FORM IN THE WISCONSIN RIVER VALLEY BECAUSE
OF THE WIND BEING ORTHAGONAL TO THE VALLEY. COMBINATION OF DRIER
AIR...925MB TEMPS RANGING FROM 12C EAST TO 15C WEST AT 18Z
MONDAY...AND SOUTHERLY BREEZE SHOULD ALLOW TEMPERATURES TO CLIMB
INTO THE UPPER 60S TO LOW 70S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 209 PM CDT SUN SEP 22 2013
FIRST ITEM OF INTEREST IS THE SHORTWAVE TROUGH OVER SOUTH DAKOTA AND
NEBRASKA ON MONDAY. MODELS ARE IN GOOD AGREEMENT OF THE TROUGH
WEAKENING AS IT GETS LIFTED TOWARDS THE FORECAST AREA ON
TUESDAY...IN RESPONSE TO RUNNING INTO THE RIDGING AHEAD OF IT. WITH
THE TROUGH WEAKENING...THE 850MB MOISTURE TRANSPORT ACCOMPANYING IT
ALSO BEGINS TO FALL APART. HOW QUICK THE WEAKENING OF THE TROUGH AND
ASSOCIATED 850MB MOISTURE TRANSPORT OCCURS WILL DETERMINE WHETHER
ANY PRECIPITATION GETS INTO THE FORECAST AREA. THE 22.12Z GFS
CONTINUES TO SUGGEST THE TROUGH WILL STILL BE STRONG ENOUGH TO BRING
SOME SHOWERS TUESDAY AFTERNOON AND EVENING TO LOCATIONS WEST OF THE
MS RIVER. MEANWHILE THE 22.12Z NAM/CANADIAN/UKMET AND 22.00Z/12Z
ECMWF ARE ALL DRY DUE TO THEM WEAKENING THE TROUGH AND MOISTURE
TRANSPORT QUICKER. MODEL CONSENSUS WOULD POINT TO A DRY
FORECAST...BUT HONORED THE GFS AND PREVIOUS FORECAST WITH 20 PERCENT
CHANCES WEST OF THE MS RIVER FOR TUESDAY AFTERNOON.
ANOTHER UPPER RIDGE IS FORECAST TO COME IN BEHIND THE TUESDAY TROUGH
BECAUSE OF A VERY DEEP TROUGH PROGGED TO FORM OVER THE WESTERN U.S.
ON WEDNESDAY. 500MB STANDARDIZED ANOMALIES OVER NEVADA AND
CALIFORNIA AT 00Z THU ARE 3 BELOW NORMAL. HEADING THROUGH THURSDAY
AND FRIDAY...THE TROUGH BEGINS TO LIFT OUT INTO THE NORTHERN
PLAINS...MOST LIKELY IN A POSITIVE TILT...CAUSING A HIGHLY AMPLIFIED
RIDGE TO DEVELOP OVER THE WESTERN GREAT LAKES REGION. SUBSIDENCE
WITH THIS RIDGE WILL KEEP THE FORECAST AREA DRY WEDNESDAY THROUGH
FRIDAY. EXPECT INCREASING SOUTHERLY WINDS AHEAD OF THE TROUGH TO
BRING WARMER AIR TO THE AREA AS WELL...WITH 925MB TEMPS PROGGED TO
CLIMB TO 14-17C ON WEDNESDAY AND THURSDAY...THEN TO 16-19C ON
FRIDAY. DPVA FORCING WITH THE TROUGH SHOULD APPROACH THE AREA FRIDAY
NIGHT...ALONG WITH A SURFACE COLD FRONT. ALL INDICATIONS ARE THAT
THE SOUTHERN PORTION OF THE TROUGH AND COLD FRONT WILL PASS THROUGH
THE FORECAST AREA EITHER SATURDAY OR SATURDAY NIGHT. ONCE THE TROUGH
AXIS PASSES...THE PRECIPITATION WILL END. PLAN ON A COOLER SATURDAY
DUE TO THE COMBINATION OF THE FRONTAL PASSAGE AND PRECIPITATION.
FOR SUNDAY AND EVEN HEADING INTO NEXT WEEK...GOOD MODEL CONTINUITY
EXISTS OF RIDGING STRENGTHENING ACROSS THE WESTERN U.S. AND INTO
SOUTHWEST CANADA. THIS WILL EVENTUALLY SET UP SOME TROUGHING
DOWNSTREAM OVER THE GREAT LAKES REGION. THE 22.12Z ECMWF IS VERY
QUICK AT DEVELOPING THIS TROUGHING...PHASING THE SOUTHERN PORTION OF
THE TROUGH ON SATURDAY WITH TROUGHING TRYING TO SET UP OVER THE
GREAT LAKES REGION. THE RESULT IS A WOUND UP LOW NEAR CHICAGO AT 12Z
SUNDAY. DO NOT HAVE MUCH CONFIDENCE OF THIS OCCURRING...BEING A
PHASING SCENARIO...THUS HAVE WENT WITH THE IDEA OF DRYING COMING IN
BEHIND THE SOUTHERN PORTION OF THE TROUGH. TEMPERATURES LOOK TO BE
JUST SLIGHTLY COOLER ON SUNDAY AS 925MB TEMPS FALL TO 10-13C.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1120 PM CDT SUN SEP 22 2013
AS RIDGE RETREATS TO THE EAST...BROAD SOUTHEAST LOW LEVEL FLOW WILL
CONTINUE THROUGH MONDAY. VFR CONDITIONS WILL PREVAIL IN THIS QUIET
REGIME.
EVEN AS SHORT WAVE TROUGH MOVES OUT OF THE ROCKIES...DRY AIRMASS
WILL LIMIT CLOUDS UNTIL WAVE IS MUCH CLOSER. SYSTEM ALSO PROGGED TO
WEAKEN AS IT GETS CLOSER WHICH COULD ALSO LIMIT IMPACT GOING INTO
TUESDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...SHEA
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
936 AM EDT MON SEP 23 2013
.UPDATE...
THE WEATHER PATTERN IN PLACE ACROSS THE REGION THIS MORNING IS
RATHER ACTIVE WITH A FRONTAL BOUNDARY DRAPED ACROSS NORTH FLORIDA
AND DEEP TROPICAL MOISTURE STREAMING IN FROM THE SOUTHWEST AHEAD
OF A TROUGH AND ASSOCIATED SURFACE LOW ALONG THE NORTHERN GULF
COAST. RADAR IMAGERY THIS MORNING SHOWS A LINE OF SHOWERS AND
STORMS MOVING NORTHEAST THROUGH THE CENTRAL AND SOUTHERN ZONES
WITH ANOTHER AREA OF RAIN OVER THE NORTHERN ZONES MOVING WEST TO
EAST IN ASSOCIATION WITH THE BOUNDARY. MORNING SOUNDINGS FROM
ACROSS THE REGION ARE ALL VERY MOIST AND WHEN COMBINED WITH
CONVERGENCE ALONG THE FRONTAL BOUNDARY TO THE NORTH AND SUPPORT
FROM THE TROUGH...RAIN CHANCES WILL BE HIGH THROUGH THE DAY TODAY.
THE HRRR AND OTHER HI-RES MODELS SUPPORT THIS THINKING. MADE SOME
UPDATES TO POPS FOR THIS MORNING INTO EARLY AFTERNOON BUT
OTHERWISE JUST ADJUSTED WINDS AND TEMPS BASED ON RECENT
OBSERVATIONS. NO OTHER UPDATES ARE PLANNED FOR THIS MORNING.
&&
.AVIATION...
VFR CONDITIONS WILL DETERIORATE AS SHOWERS MOVE INTO AREA TERMINALS
THIS MORNING...AND CONTINUE THROUGHOUT THE DAY. THUNDERSTORMS ARE
POSSIBLE ACROSS SOUTHERN TERMINALS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 87 76 87 77 / 70 50 70 40
FMY 88 76 88 77 / 70 50 70 40
GIF 87 74 87 74 / 70 50 70 40
SRQ 87 78 88 78 / 70 50 70 40
BKV 87 74 88 73 / 70 50 70 40
SPG 87 78 87 79 / 70 50 70 40
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE...05/CARLISLE
AVIATION...20/BARRON AND 75/LEWIS
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
920 AM EDT MON SEP 23 2013
.DISCUSSION...
...LOCALLY HEAVY RAIN EXPECTED ACROSS EAST CENTRAL FLORIDA INTO MID
WEEK...
.UPDATE...DEEP MOISTURE WITH PWATS FROM 2.25-2.30 INCHES ACROSS THE
SRN PENINSULA PER 12Z SOUNDINGS WILL BE ADVECTED NWD WITH INCREASING
SSW/SW FLOW IN THE H9-H8 LAYER TO 15-20 KNOTS ACROSS THE SRN HALF OF
THE FORECAST AREA THIS AFTERNOON. MODELS HINT AT A LOW TO MID LVL
SHORTWAVE TROUGH ACROSS THE ERN GULF THAT WILL ENHANCE NORTHEASTWARD
MOVING SHOWERS AND STORMS INTO CENTRAL AND SRN SECTIONS OF EAST
CENTRAL FLORIDA BY EARLY TO MID AFTERNOON. QUASI STATIONARY BOUNDARY
ACROSS THE NRN PENINSULA AND SOUPY AIRMASS SOUTH OF THE BOUNDARY
WILL LIKELY PROVIDE FOCUS FOR SHOWERS AND STORMS ACROSS NRN SECTIONS
AS WELL INTO THE MID TO LATE AFTERNOON. FIRST ROUND OF CONVECTION IS
ALREADY MOVING NE FROM SW FLORIDA AND WILL APPROACH SRN INTERIOR
SECTIONS BY MID DAY. WILL CONTINUE LIKELY RAIN CHANCES. HIGHS
EXPECTED MAINLY IN THE UPR 80S WITH SOME AREAS APPROACHING 90 THAT
SEE LESS CLOUD COVER ACROSS THE SOUTH. EXPECT LOCALLY HEAVY RAINFALL
AMOUNTS UP TO AROUND TWO INCHES...ESPECIALLY ACROSS SRN/CENTRAL
SECTIONS WHERE FILTERED SUNSHINE THIS MORNING SHOULD PROVIDE
SLIGHTLY BETTER INSTABILITY. WARM MID LEVEL TEMPERATURES INDICATIVE
OF TROPICAL AIRMASS WITH HIGH PWATS. EXPECT SOME GUSTY WINDS TO
40-45 MPH WITH STRONGEST STORMS.
&&
.AVIATION...CURRENT EXTRAPOLATION PLACES SW FL CONVECTION CLOSE TO A
KMCO-KVRB-KFPR LINE AROUND 18Z. WITH STRONGER DEVELOPING LOW LVL
SW FLOW ACROSS SRN PORTIONS OF EAST CENTRAL FL MAY NEED TO ADJUST
TIMING OF SHRA/TSRA JUST A BIT SOONER. HRRR MODEL SLIGHTLY SLOWER
WITH CONVECTION MOVING NE. WILL KEEP AN EYE ON RADAR TRENDS AND
ADJUST CONVECTIVE TIMING AS NECESSARY.
&&
.MARINE...
NEARLY CALM WIND CURRENTLY AT BUOY 41009 WITH SEAS 2 FT AT BUOY
41009/41114. MAIN CONCERN TODAY WILL BE SHOWERS/TSTMS MOVING FROM
THE MAINLAND INTO THE NEAR SHORE WATERS FROM THE BREVARD-VOLUSIA
COUNTY LINE SOUTH TO JUPITER INLET THIS AFTERNOON. POTENTIAL FOR 35
KT GUSTS WITH STORMS. BUOY 41009 RECORDED A 31 KT GUST YESTERDAY AND
KDAB RECORDED A GUST TO 35 KNOTS. SIMILAR GUST POTENTIAL TODAY FROM
30-40 KTS EXPECTED WITH STRONGEST STORMS.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
VOLKMER/WIMMER
AREA FORECAST DISCUSSION
NWS TOPEKA KS
630 AM CDT Mon Sep 23 2013
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 302 AM CDT MON SEP 23 2013
Water vapor imagery as of 07z depicts the center of the strong upper
shortwave trough across southern Colorado shifting eastward.
Meanwhile an abundant amount of subsidence ahead of the wave was
noted. A frontal boundary stretched across the northern Gulf is
responsible in blocking moisture from spreading northward into the
region. At the surface, observations depict the surface trough
positioned across eastern Colorado with gusty southerly winds
stretching into western Kansas.
As the above mentioned upper wave lifts northeast into the central
plains Monday afternoon, the surface low edges into western Kansas,
gradually increasing southerly wind speeds between 20 and 25 mph
this afternoon. Gusts over 35 mph are expected as deeper mixing and
dry air aloft restrains dewpoints to the low 50s. Daytime heating
combined with convergence along and ahead of a weak cold front
shifting east may trigger scattered convection this afternoon and
evening. The recent runs of the HRRR and 4-KM ARW support this
thinking as north central areas stand to see the best chance of
precipitation. While speed shear is prevalent at 50 kts up to 6 Km,
uncertainty exists as to if the updrafts are able to maintain
themselves and reach the CWA border. Weak instability, mid level
lapse rates around 5-6 degrees C/Km, and meager moisture in place
can only warrant a slight chance mention of showers with perhaps an
isolated thunderstorm through this evening. The upper trough and
precipitation lifts out of the area overnight as the frontal
boundary and associated cloud cover passes through the area dry.
Expect highs today similar to previous afternoons with readings
generally in the upper 70s. By this evening, increasing insulation
from cloud cover and gusty southerly winds will boost low
temperatures a few degrees into the middle 50s.
.LONG TERM...(Tuesday through Sunday)
Issued at 302 AM CDT MON SEP 23 2013
Tuesday through Thursday continues to look dry as forcing from
upper trough moves east of the area and ridging develops. Models
show some weak cold air advection through part of the day
Tuesday. There is also better agreement on some higher 850MB RH
hanging in on the back side of the departing system implying skies
could be partly cloudy over eastern KS. Because of the cooler air
advecting south and east and the potential for a little more
clouds, have trended highs for Tuesday down a degree or two. By
Wednesday morning, skies could clear out with winds becoming light
and variable as a weak surface ridge axis passes over eastern KS
setting up conditions for good radiational cooling. Because of
this have also trended lows Wednesday morning down with some
readings potentially nearing 50. By Thursday the models are in
good agreement that southerly return flow will have begun with
better moisture advecting north. Therefore Highs in the 80s and
lows in the 60s appear reasonable.
For Thursday night through Saturday, the models remain in good
agreement with the overall synoptic pattern with only some slight
timing differences in the frontal passage. However it looks like
the most likely timing is for the front to move through late
Friday night and Saturday morning. If models continue to converge
on this solution, later shifts may want to increase pops to
likely as there appears to be plenty of moisture with modest
instability for the front to come through and lift. With the front
expected to remain north of the area most of the day Friday, temps
are expected to remain above normal with readings in the 80s.
Saturday looks to see the bulk of the cool down as cold air
advection increases through the day.
Precip should be all but over Saturday evening as the front is
progged to be into southeast KS and southern MO. Central and
eastern KS should see clearing skies into Sunday as a modified
pacific surface ridge builds into the plains and mid level heights
gradually rise. WPC tends to favor the more amplified pattern of
the ECMWF for the end of the weekend with a closed low eventually
developing to the east. This will likely keep Fall like temps for
the forecast area on Sunday.
&&
.AVIATION...(For the 12Z TAFs through 12Z Tuesday Morning)
Issued at 548 AM CDT MON SEP 23 2013
VFR conditions through most of the forecast period for KTOP/KFOE/KMHK.
Light and vrb winds this morning increase aft 15z with southerly
speeds sustained near 16 kts at KTOP/KFOE and 20 kts at KMHK. Wind
gusts aoa 24 kts are common through 0z. Winds back to southeast
and weaken below 10 kts aft 0z. High clouds increase in advance of
a weak cold front impacting KMHK aft 08z as light winds veer to
the west. Any developing showers or thunder should remain north of
terminals with little confidence to mention attm. A few short term
guidance tries to bring MVFR cigs to KMHK aft 08z. Will leave at
VFR and evaluate at next issuance. Front impacts KTOP/KFOE beyond
forecast period.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Bowen
LONG TERM...Wolters
AVIATION...Bowen
AREA FORECAST DISCUSSION
NWS GAYLORD MI
805 AM EDT MON SEP 23 2013
.SYNOPSIS...
ISSUED AT 249 AM EDT MON SEP 23 2013
HIGH PRESSURE WILL BRING AN EXTENDED PERIOD OF DRY WEATHER AND
MOSTLY CLEAR SKIES THROUGH THE WORK WEEK. HIGH TEMPERATURES WILL
SLOWLY MODERATE...WITH READINGS WELL ABOVE NORMAL WEDNESDAY THROUGH
SATURDAY. OVERNIGHT LOWS WILL BE COOL...AND FROST REMAINS A
POSSIBILITY IN MANY AREAS AGAIN TONIGHT.
&&
.UPDATE...
ISSUED AT 804 AM EDT MON SEP 23 2013
UPDATE TO EXPIRE FROST/FREEZE HEADLINES.
UPDATE ISSUED AT 713 AM EDT MON SEP 23 2013
CLOUD COVER HAS EXPANDED A BIT FURTHER INTO NE LOWER MI...THOUGH
THAT EXPANSION HAS STALLED OVER THE LAST 60-90MIN. THIS PROMISES
ADDITIONAL EROSION...ESPECIALLY AS THE SUN GOES TO WORK.
STILL...HAVE TENDED TO SLOW DOWN CLEARING TRENDS THIS MORNING.
OTHER AREAS IMPACTED BY AT LEAST PARTLY CLOUDY CONDITIONS THIS
MORNING INCLUDE WESTERN MACK AND FAR WESTERN CHIP...AND
GLADWIN/ARENAC COUNTIES.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 249 AM EDT MON SEP 23 2013
LARGE CANADIAN HIGH PRESSURE SLIDES INTO THE EASTERN LAKES THROUGH
TONIGHT WITH DEVELOPING WEAK RETURN FLOW ACROSS NORTHERN
MICHIGAN. SENSIBLE WEATHER CONCERNS IN THE SHORT TERM FOCUSED
PRIMARILY ON CLOUD TRENDS AND MIN TEMPERATURES TONIGHT.
TODAY...LOW LEVEL FLOW VEERS SOUTHEAST ON WESTERN PERIPHERY OF HIGH
PRESSURE WITH STRENGTHENING WARM AIR ADVECTION PUSHING H8
TEMPERATURES INTO THE +7C TO +9C RANGE. BRINGING THESE TEMPS DOWN
DRY ADIABATICALLY YIELDS HIGHS IN THE UPPER 50S TO MID 60S
/WARMEST WEST/. TRICKY CLOUD FORECAST WITH PLENTY OF RESIDUAL LOW
LEVEL MOISTURE ALONG THE LAKE HURON COAST/SAGINAW BAY TRAPPED
BENEATH SUBSIDENCE INVERSION WITH FAVORABLE DELTA T/S AND WEAK
ONSHORE FLOW. THE RUC 925-850MB RH FIELDS SHOW THESE LOWER CLOUDS
PLAGUING LAKE HURON COASTAL AREAS FROM ALPENA SOUTHWARD TOWARD SAGINAW
BAY THROUGH THE MORNING HOURS. AS DELTA T/S DECREASE WITH WARMING
ALOFT AND MUCH DRIER AIR WORKS INTO THE AREA /PWATS AROUND
0.4/...THE CLOUDS SHOULD /HOPEFULLY/ DISSIPATE. AS IS FREQUENTLY
THE CASE THIS TIME OF YEAR WITH REGARD TO LOW CLOUDS...WOULD NOT
BE SURPRISED IF THEY ENDED UP MORE PERSISTENT THAN CURRENTLY
FORECAST.
TONIGHT...ANOTHER POTENTIAL FROSTY NIGHT FOR PORTIONS OF THE AREA.
EXCELLENT RADIATIONAL COOLING SCENARIO ONCE AGAIN WITH CLEAR SKIES
AND LIGHT WINDS. SEE LITTLE REASON WHY LOW TEMPS WILL NOT DIP INTO
THE MIDDLE 30S OVER PORTIONS OF NORTHERN LOWER /ESPECIALLY EAST OF
I-75/...WITH SOME READINGS LIKELY INTO THE LOWER 30S IN THE
TYPICALLY COLDER LOCATIONS. WILL "BEEF UP" THE FROST WORDING IN
THE HWO...BUT WILL LEAVE HEADLINE DECISIONS TO THE DAY SHIFT BASED
ON LATEST OBS/MODEL TRENDS. AREAS OF FOG ALSO LIKELY...PARTICULARLY
IN THE COLDER VALLEY LOCATIONS AND AROUND INLAND LAKES.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 249 AM EDT MON SEP 23 2013
A SPECTACULAR WORK WEEK IS AHEAD (HARD TO IMAGINE A MULTI-DAY
STRETCH WITH QUIETER LONG-TERM FORECASTS THAN THE LAST FEW). THE ONE
INCOMING SYSTEM OF ANY NOTE IS A VIGOROUS SHORTWAVE IN THE 4-CORNERS
REGION EARLY THIS MORNING. THIS SYSTEM WILL EMERGE INTO THE CENTRAL
PLAINS TODAY...BUT THEN ENCOUNTER A BLOCKED PATTERN TO THE EAST...
WITH A STALLED UPPER LOW OVER NEW BRUNSWICK AND RIDGING IN THE
LAKES. THE INCOMING WAVE/S SOLUTION TO THIS PROBLEM IS CUT
UNDERNEATH THE RIDGE...MOVING THRU THE OHIO VALLEY ON WEDNESDAY.
THAT WILL BE TOO FAR SOUTH TO HAVE MUCH IMPACT ON US. THAT LEAVES
TEMPS AS THE ONLY CONCERN OF NOTE.
TUESDAY INTO WEDNESDAY...500MB RIDGING...WHICH IS OVERHEAD TO START
TUE MORNING...WILL DRIFT EAST TO LAKE HURON THRU TUE NIGHT. AS THE
UPPER LOW PASSES TO OUR SOUTH...THAT RIDGE WILL BE DISRUPTED...BUT
RIDGING WILL BEGIN TO FOLD OVER TOP OF THE LOW AND POKE IN FROM THE
SW ON WEDNESDAY. AT THE SURFACE...HIGH PRESSURE WILL BE A SEMI-
PERMANENT FEATURE IN THE VICINITY OF LAKE HURON. THIS PERSISTENT
RIDGING SURFACE AND ALOFT WILL MAINTAIN DEEP SUBSIDENCE AND ABUNDANT
DRY AIR. 850-700MB RH LEVELS ARE BELOW 20 PERCENT THROUGHOUT...AND
ARE BELOW 10 PERCENT MOST OF THE TIME.
THE UPPER LOW PASSING TO OUR SOUTH WILL LIKELY FEED SOME THIN CIRRUS
OVERHEAD TUE NIGHT/WED. OTHERWISE...SKIES WILL BE CLEAR. MAX TEMPS
WILL BE MAINLY IN THE MID TO UPPER 60S BOTH DAYS...WITH A FEW 70S
POSSIBLE WEDNESDAY. MIN TEMPS 40-45 FOR MOST...BUT THE INLAND COOL
SPOTS WILL LOWER INTO THE MID/UPPER 30S.
REST OF THE FORECAST...500MB RIDGING GETS PUMPED BACK INTO THE
REGION FROM THE SW FOR THE REST OF THE WORK WEEK. THU/FRI LOOK VERY
PLEASANT AND MILD...WITH MAX TEMPS MAINLY IN THE 70S.
THE GFS REMAINS A FAST OUTLIER WHEN IT COMES TO BREAKING DOWN THE
RIDGE...AND USHERING IN OUR NEXT CHANCE FOR PRECIP. THE ECMWF HAS
BEEN MUCH MORE CONSISTENT...AND IS PREFERRED. HEIGHTS WILL BE
STEADILY ERODED THIS WEEKEND...WITH THE ACTUAL TROF AXIS ARRIVING
MOST LIKELY ON SUNDAY. THIS SUPPORTS DRY WX INTO FRIDAY NIGHT...AND
CHANCE POPS SAT THRU SUNDAY. SATURDAY WILL REMAIN WARM...WITH
READING CLOSER TO CLIMO SUNDAY.
THOUGH IT LIES BEYOND THE SCOPE OF THIS FORECAST...DIFFICULT TO TELL
HOW LONG THE UNSETTLED WX WILL LAST. 12Z ECMWF WANTED TO LINGER THE
TROF IN THE REGION LONG ENOUGH TO REINFORCE IT WITH ARCTIC
ENERGY...CARVING OUT AN UNPLEASANT UPPER LOW OVER THE LAKES REGION
NEXT WEEK. WE SHALL SEE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 713 AM EDT MON SEP 23 2013
VFR.
HIGH PRESSURE CENTERED OVER NE ONTARIO WILL DRIFT SOUTH TO LAKE
HURON OVER THE NEXT 24 HOURS. THE STILL COOL AIRMASS ASSOCIATED
WITH THE HIGH IS SUPPORTING SOME LAKE-INDUCED CLOUD COVER...
ESPECIALLY INTO NE LOWER MI (APN). THIS WILL ERODE WITH TIME TODAY
AS WE WARM. SKIES SHOULD BE CLEAR ACROSS THE AREA TONIGHT. WINDS
WILL BE LIGHT AND VARIABLE.
&&
.MARINE...
ISSUED AT 249 AM EDT MON SEP 23 2013
A LARGE AREA OF HIGH PRESSURE WILL ANCHORED ACROSS THE GREAT LAKES
FOR THE NEXT SEVERAL DAYS. WITH AN OVERALL LIGHT WIND REGIME...NO
HEADLINES ARE ANTICIPATED.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...MB
SYNOPSIS...JZ
SHORT TERM...JK
LONG TERM...JZ
AVIATION...JZ
MARINE...JK
AREA FORECAST DISCUSSION
NWS GAYLORD MI
713 AM EDT MON SEP 23 2013
.SYNOPSIS...
ISSUED AT 249 AM EDT MON SEP 23 2013
HIGH PRESSURE WILL BRING AN EXTENDED PERIOD OF DRY WEATHER AND
MOSTLY CLEAR SKIES THROUGH THE WORK WEEK. HIGH TEMPERATURES WILL
SLOWLY MODERATE...WITH READINGS WELL ABOVE NORMAL WEDNESDAY THROUGH
SATURDAY. OVERNIGHT LOWS WILL BE COOL...AND FROST REMAINS A
POSSIBILITY IN MANY AREAS AGAIN TONIGHT.
&&
.UPDATE...
ISSUED AT 713 AM EDT MON SEP 23 2013
CLOUD COVER HAS EXPANDED A BIT FURTHER INTO NE LOWER MI...THOUGH
THAT EXPANSION HAS STALLED OVER THE LAST 60-90MIN. THIS PROMISES
ADDITIONAL EROSION...ESPECIALLY AS THE SUN GOES TO WORK.
STILL...HAVE TENDED TO SLOW DOWN CLEARING TRENDS THIS MORNING.
OTHER AREAS IMPACTED BY AT LEAST PARTLY CLOUDY CONDITIONS THIS
MORNING INCLUDE WESTERN MACK AND FAR WESTERN CHIP...AND
GLADWIN/ARENAC COUNTIES.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 249 AM EDT MON SEP 23 2013
LARGE CANADIAN HIGH PRESSURE SLIDES INTO THE EASTERN LAKES THROUGH
TONIGHT WITH DEVELOPING WEAK RETURN FLOW ACROSS NORTHERN
MICHIGAN. SENSIBLE WEATHER CONCERNS IN THE SHORT TERM FOCUSED
PRIMARILY ON CLOUD TRENDS AND MIN TEMPERATURES TONIGHT.
TODAY...LOW LEVEL FLOW VEERS SOUTHEAST ON WESTERN PERIPHERY OF HIGH
PRESSURE WITH STRENGTHENING WARM AIR ADVECTION PUSHING H8
TEMPERATURES INTO THE +7C TO +9C RANGE. BRINGING THESE TEMPS DOWN
DRY ADIABATICALLY YIELDS HIGHS IN THE UPPER 50S TO MID 60S
/WARMEST WEST/. TRICKY CLOUD FORECAST WITH PLENTY OF RESIDUAL LOW
LEVEL MOISTURE ALONG THE LAKE HURON COAST/SAGINAW BAY TRAPPED
BENEATH SUBSIDENCE INVERSION WITH FAVORABLE DELTA T/S AND WEAK
ONSHORE FLOW. THE RUC 925-850MB RH FIELDS SHOW THESE LOWER CLOUDS
PLAGUING LAKE HURON COASTAL AREAS FROM ALPENA SOUTHWARD TOWARD SAGINAW
BAY THROUGH THE MORNING HOURS. AS DELTA T/S DECREASE WITH WARMING
ALOFT AND MUCH DRIER AIR WORKS INTO THE AREA /PWATS AROUND
0.4/...THE CLOUDS SHOULD /HOPEFULLY/ DISSIPATE. AS IS FREQUENTLY
THE CASE THIS TIME OF YEAR WITH REGARD TO LOW CLOUDS...WOULD NOT
BE SURPRISED IF THEY ENDED UP MORE PERSISTENT THAN CURRENTLY
FORECAST.
TONIGHT...ANOTHER POTENTIAL FROSTY NIGHT FOR PORTIONS OF THE AREA.
EXCELLENT RADIATIONAL COOLING SCENARIO ONCE AGAIN WITH CLEAR SKIES
AND LIGHT WINDS. SEE LITTLE REASON WHY LOW TEMPS WILL NOT DIP INTO
THE MIDDLE 30S OVER PORTIONS OF NORTHERN LOWER /ESPECIALLY EAST OF
I-75/...WITH SOME READINGS LIKELY INTO THE LOWER 30S IN THE
TYPICALLY COLDER LOCATIONS. WILL "BEEF UP" THE FROST WORDING IN
THE HWO...BUT WILL LEAVE HEADLINE DECISIONS TO THE DAY SHIFT BASED
ON LATEST OBS/MODEL TRENDS. AREAS OF FOG ALSO LIKELY...PARTICULARLY
IN THE COLDER VALLEY LOCATIONS AND AROUND INLAND LAKES.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 249 AM EDT MON SEP 23 2013
A SPECTACULAR WORK WEEK IS AHEAD (HARD TO IMAGINE A MULTI-DAY
STRETCH WITH QUIETER LONG-TERM FORECASTS THAN THE LAST FEW). THE ONE
INCOMING SYSTEM OF ANY NOTE IS A VIGOROUS SHORTWAVE IN THE 4-CORNERS
REGION EARLY THIS MORNING. THIS SYSTEM WILL EMERGE INTO THE CENTRAL
PLAINS TODAY...BUT THEN ENCOUNTER A BLOCKED PATTERN TO THE EAST...
WITH A STALLED UPPER LOW OVER NEW BRUNSWICK AND RIDGING IN THE
LAKES. THE INCOMING WAVE/S SOLUTION TO THIS PROBLEM IS CUT
UNDERNEATH THE RIDGE...MOVING THRU THE OHIO VALLEY ON WEDNESDAY.
THAT WILL BE TOO FAR SOUTH TO HAVE MUCH IMPACT ON US. THAT LEAVES
TEMPS AS THE ONLY CONCERN OF NOTE.
TUESDAY INTO WEDNESDAY...500MB RIDGING...WHICH IS OVERHEAD TO START
TUE MORNING...WILL DRIFT EAST TO LAKE HURON THRU TUE NIGHT. AS THE
UPPER LOW PASSES TO OUR SOUTH...THAT RIDGE WILL BE DISRUPTED...BUT
RIDGING WILL BEGIN TO FOLD OVER TOP OF THE LOW AND POKE IN FROM THE
SW ON WEDNESDAY. AT THE SURFACE...HIGH PRESSURE WILL BE A SEMI-
PERMANENT FEATURE IN THE VICINITY OF LAKE HURON. THIS PERSISTENT
RIDGING SURFACE AND ALOFT WILL MAINTAIN DEEP SUBSIDENCE AND ABUNDANT
DRY AIR. 850-700MB RH LEVELS ARE BELOW 20 PERCENT THROUGHOUT...AND
ARE BELOW 10 PERCENT MOST OF THE TIME.
THE UPPER LOW PASSING TO OUR SOUTH WILL LIKELY FEED SOME THIN CIRRUS
OVERHEAD TUE NIGHT/WED. OTHERWISE...SKIES WILL BE CLEAR. MAX TEMPS
WILL BE MAINLY IN THE MID TO UPPER 60S BOTH DAYS...WITH A FEW 70S
POSSIBLE WEDNESDAY. MIN TEMPS 40-45 FOR MOST...BUT THE INLAND COOL
SPOTS WILL LOWER INTO THE MID/UPPER 30S.
REST OF THE FORECAST...500MB RIDGING GETS PUMPED BACK INTO THE
REGION FROM THE SW FOR THE REST OF THE WORK WEEK. THU/FRI LOOK VERY
PLEASANT AND MILD...WITH MAX TEMPS MAINLY IN THE 70S.
THE GFS REMAINS A FAST OUTLIER WHEN IT COMES TO BREAKING DOWN THE
RIDGE...AND USHERING IN OUR NEXT CHANCE FOR PRECIP. THE ECMWF HAS
BEEN MUCH MORE CONSISTENT...AND IS PREFERRED. HEIGHTS WILL BE
STEADILY ERODED THIS WEEKEND...WITH THE ACTUAL TROF AXIS ARRIVING
MOST LIKELY ON SUNDAY. THIS SUPPORTS DRY WX INTO FRIDAY NIGHT...AND
CHANCE POPS SAT THRU SUNDAY. SATURDAY WILL REMAIN WARM...WITH
READING CLOSER TO CLIMO SUNDAY.
THOUGH IT LIES BEYOND THE SCOPE OF THIS FORECAST...DIFFICULT TO TELL
HOW LONG THE UNSETTLED WX WILL LAST. 12Z ECMWF WANTED TO LINGER THE
TROF IN THE REGION LONG ENOUGH TO REINFORCE IT WITH ARCTIC
ENERGY...CARVING OUT AN UNPLEASANT UPPER LOW OVER THE LAKES REGION
NEXT WEEK. WE SHALL SEE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 713 AM EDT MON SEP 23 2013
VFR.
HIGH PRESSURE CENTERED OVER NE ONTARIO WILL DRIFT SOUTH TO LAKE
HURON OVER THE NEXT 24 HOURS. THE STILL COOL AIRMASS ASSOCIATED
WITH THE HIGH IS SUPPORTING SOME LAKE-INDUCED CLOUD COVER...
ESPECIALLY INTO NE LOWER MI (APN). THIS WILL ERODE WITH TIME TODAY
AS WE WARM. SKIES SHOULD BE CLEAR ACROSS THE AREA TONIGHT. WINDS
WILL BE LIGHT AND VARIABLE.
&&
.MARINE...
ISSUED AT 249 AM EDT MON SEP 23 2013
A LARGE AREA OF HIGH PRESSURE WILL ANCHORED ACROSS THE GREAT LAKES
FOR THE NEXT SEVERAL DAYS. WITH AN OVERALL LIGHT WIND REGIME...NO
HEADLINES ARE ANTICIPATED.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...FREEZE WARNING UNTIL 8 AM EDT THIS MORNING FOR MIZ016-017-022-
023-027>029-033>035-041.
FROST ADVISORY UNTIL 8 AM EDT THIS MORNING FOR MIZ008-015-018-
019-021-024>026-030>032-036-042.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JZ
SYNOPSIS...JZ
SHORT TERM...JK
LONG TERM...JZ
AVIATION...JZ
MARINE...JK
AREA FORECAST DISCUSSION
NWS NORMAN OK
637 AM CDT MON SEP 23 2013
.UPDATE...
REMOVED POPS ACROSS NORTHWESTERN OKLAHOMA THIS MORNING.
&&
.DISCUSSION...
ANY SHOWER/ISOLATED THUNDER ACTIVITY ACROSS THE PANHANDLES HAS
LIFTED NORTH/NORTHEAST INTO FAR SOUTHWESTERN KANSAS. DO NOT EXPECT
ANY SHOWERS TO IMPACT FAR NORTHWESTERN OKLAHOMA THIS MORNING.
JTK
&&
.PREV DISCUSSION... /ISSUED 554 AM CDT MON SEP 23 2013/
AVIATION...
VFR CONDITIONS ARE EXPECTED. GUSTY SOUTH WIND IN WESTERN OKLAHOMA
WILL GIVE WAY TO LIGHT NORTH WINDS BEHIND A WEAK FRONT OVERNIGHT.
PREV DISCUSSION... /ISSUED 507 AM CDT MON SEP 23 2013/
UPDATE...
UPDATED POPS FOR THIS MORNING...
DISCUSSION...
REMOVED POPS FROM 11Z TO 12Z PER RADAR ANALYSIS OF ONGOING
SHOWERS ACROSS CENTRAL TX/OK PANHANDLES BEST FOCUS FOR DEVELOPMENT
THIS MORNING REMAINS JUST EAST OF THE WEAK SFC FRONT...WHICH
CURRENTLY EXTENDS FROM WRN KS THROUGH ERN NM. WV SAT SHOWS THE
PRIMARY UPPER LOW LIFTING N/NE OFF THE NRN CO FRONT RANGE...WITH
BETTER FOCUS FOR PRECIP ACROSS ERN CO/WRN KS INTO SWRN NE. WITH
THE CURRENT TRACK OF THE SFC LOW ACROSS E. CENTRAL CO AND THE
PARENT 500MB LOW...WOULD NOT BE SURPRISED IF SHOWERS THIS MORNING
JUST SKIRT FAR NWRN OK...OR MISS COMPLETELY. 07Z RUN OF THE HRRR
SUPPORTS THE LATTER SOLUTION...WITH SHOWERS LIFTING NORTH ACROSS
THE OK PANHANDLE INTO SWRN KS MISSING NWRN OK COMPLETELY.
HOWEVER... THIS SOLUTION HAS THE SRN TERMINUS OF CONVECTION
FARTHER NORTH THAN CURRENTLY OBSERVED. WILL CONTINUE TO RUN WITH
SLIGHT CHANCE POPS ACROSS FAR NWRN OK THROUGH 14Z...AS ENSEMBLE
RUNS OF THE HRRR AND SOLUTIONS FROM THE NSSL AND OUN WRF CLIP FAR
NWRN OK WITH A SHOWER OR TWO THROUGH 14Z.
JTK
PREV DISCUSSION... /ISSUED 355 AM CDT MON SEP 23 2013/
DISCUSSION...
AN UPPER TROUGH MOVING QUICKLY INTO THE CENTRAL PLAINS FROM THE
WEST WILL PASS ACROSS NORTHERN OKLAHOMA TODAY. MODELS, RADAR, AND
SATELLITE TRENDS EACH SUGGEST THAT NEARLY ALL RAIN WILL PASS NORTH
OF OKLAHOMA. THE MAIN EFFECT WILL BE MID-LEVEL CLOUDS. A WEAK
SURFACE FRONT WILL CHANGE WINDS TO THE NORTH. A TREND TOWARDS HOT
WEATHER STARTS TUESDAY AND LASTS INTO FRIDAY BEFORE A STRONGER
UPPER LEVEL SYSTEM BRINGS STRONGER LIFT ACROSS OKLAHOMA AND A
FRONT MOVES INTO THE STATE. THE MORE HUMID BOUNDARY LAYER THAT
WILL EXIST SHOULD HAVE NO PROBLEM PRODUCING RAIN AND THUNDERSTORMS
LATE FRIDAY AND SATURDAY. COOLER AND DRIER AIR WILL FOLLOW SUNDAY.
09
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 81 58 83 57 / 0 0 0 0
HOBART OK 83 57 85 57 / 0 0 0 0
WICHITA FALLS TX 85 59 88 59 / 0 0 0 0
GAGE OK 84 52 82 55 / 10 0 0 0
PONCA CITY OK 80 57 81 55 / 10 10 0 0
DURANT OK 84 59 88 59 / 0 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
04/09/09
AREA FORECAST DISCUSSION
NWS NORMAN OK
554 AM CDT MON SEP 23 2013
.AVIATION...
VFR CONDITIONS ARE EXPECTED. GUSTY SOUTH WIND IN WESTERN OKLAHOMA
WILL GIVE WAY TO LIGHT NORTH WINDS BEHIND A WEAK FRONT OVERNIGHT.
&&
.PREV DISCUSSION... /ISSUED 507 AM CDT MON SEP 23 2013/
UPDATE...
UPDATED POPS FOR THIS MORNING...
DISCUSSION...
REMOVED POPS FROM 11Z TO 12Z PER RADAR ANALYSIS OF ONGOING
SHOWERS ACROSS CENTRAL TX/OK PANHANDLES BEST FOCUS FOR DEVELOPMENT
THIS MORNING REMAINS JUST EAST OF THE WEAK SFC FRONT...WHICH
CURRENTLY EXTENDS FROM WRN KS THROUGH ERN NM. WV SAT SHOWS THE
PRIMARY UPPER LOW LIFTING N/NE OFF THE NRN CO FRONT RANGE...WITH
BETTER FOCUS FOR PRECIP ACROSS ERN CO/WRN KS INTO SWRN NE. WITH
THE CURRENT TRACK OF THE SFC LOW ACROSS E. CENTRAL CO AND THE
PARENT 500MB LOW...WOULD NOT BE SURPRISED IF SHOWERS THIS MORNING
JUST SKIRT FAR NWRN OK...OR MISS COMPLETELY. 07Z RUN OF THE HRRR
SUPPORTS THE LATTER SOLUTION...WITH SHOWERS LIFTING NORTH ACROSS
THE OK PANHANDLE INTO SWRN KS MISSING NWRN OK COMPLETELY.
HOWEVER... THIS SOLUTION HAS THE SRN TERMINUS OF CONVECTION
FARTHER NORTH THAN CURRENTLY OBSERVED. WILL CONTINUE TO RUN WITH
SLIGHT CHANCE POPS ACROSS FAR NWRN OK THROUGH 14Z...AS ENSEMBLE
RUNS OF THE HRRR AND SOLUTIONS FROM THE NSSL AND OUN WRF CLIP FAR
NWRN OK WITH A SHOWER OR TWO THROUGH 14Z.
JTK
PREV DISCUSSION... /ISSUED 355 AM CDT MON SEP 23 2013/
DISCUSSION...
AN UPPER TROUGH MOVING QUICKLY INTO THE CENTRAL PLAINS FROM THE
WEST WILL PASS ACROSS NORTHERN OKLAHOMA TODAY. MODELS, RADAR, AND
SATELLITE TRENDS EACH SUGGEST THAT NEARLY ALL RAIN WILL PASS NORTH
OF OKLAHOMA. THE MAIN EFFECT WILL BE MID-LEVEL CLOUDS. A WEAK
SURFACE FRONT WILL CHANGE WINDS TO THE NORTH. A TREND TOWARDS HOT
WEATHER STARTS TUESDAY AND LASTS INTO FRIDAY BEFORE A STRONGER
UPPER LEVEL SYSTEM BRINGS STRONGER LIFT ACROSS OKLAHOMA AND A
FRONT MOVES INTO THE STATE. THE MORE HUMID BOUNDARY LAYER THAT
WILL EXIST SHOULD HAVE NO PROBLEM PRODUCING RAIN AND THUNDERSTORMS
LATE FRIDAY AND SATURDAY. COOLER AND DRIER AIR WILL FOLLOW SUNDAY.
09
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 81 58 83 57 / 0 0 0 0
HOBART OK 83 57 85 57 / 0 0 0 0
WICHITA FALLS TX 85 59 88 59 / 0 0 0 0
GAGE OK 84 52 82 55 / 20 0 0 0
PONCA CITY OK 80 57 81 55 / 10 10 0 0
DURANT OK 84 59 88 59 / 0 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
04/09/09
AREA FORECAST DISCUSSION
NWS NORMAN OK
507 AM CDT MON SEP 23 2013
.UPDATE...
UPDATED POPS FOR THIS MORNING...
&&
.DISCUSSION...
REMOVED POPS FROM 11Z TO 12Z PER RADAR ANALYSIS OF ONGOING
SHOWERS ACROSS CENTRAL TX/OK PANHANDLES BEST FOCUS FOR DEVELOPMENT
THIS MORNING REMAINS JUST EAST OF THE WEAK SFC FRONT...WHICH
CURRENTLY EXTENDS FROM WRN KS THROUGH ERN NM. WV SAT SHOWS THE
PRIMARY UPPER LOW LIFTING N/NE OFF THE NRN CO FRONT RANGE...WITH
BETTER FOCUS FOR PRECIP ACROSS ERN CO/WRN KS INTO SWRN NE. WITH
THE CURRENT TRACK OF THE SFC LOW ACROSS E. CENTRAL CO AND THE
PARENT 500MB LOW...WOULD NOT BE SURPRISED IF SHOWERS THIS MORNING
JUST SKIRT FAR NWRN OK...OR MISS COMPLETELY. 07Z RUN OF THE HRRR
SUPPORTS THE LATTER SOLUTION...WITH SHOWERS LIFTING NORTH ACROSS
THE OK PANHANDLE INTO SWRN KS MISSING NWRN OK COMPLETELY.
HOWEVER... THIS SOLUTION HAS THE SRN TERMINUS OF CONVECTION
FARTHER NORTH THAN CURRENTLY OBSERVED. WILL CONTINUE TO RUN WITH
SLIGHT CHANCE POPS ACROSS FAR NWRN OK THROUGH 14Z...AS ENSEMBLE
RUNS OF THE HRRR AND SOLUTIONS FROM THE NSSL AND OUN WRF CLIP FAR
NWRN OK WITH A SHOWER OR TWO THROUGH 14Z.
JTK
&&
.PREV DISCUSSION... /ISSUED 355 AM CDT MON SEP 23 2013/
DISCUSSION...
AN UPPER TROUGH MOVING QUICKLY INTO THE CENTRAL PLAINS FROM THE
WEST WILL PASS ACROSS NORTHERN OKLAHOMA TODAY. MODELS, RADAR, AND
SATELLITE TRENDS EACH SUGGEST THAT NEARLY ALL RAIN WILL PASS NORTH
OF OKLAHOMA. THE MAIN EFFECT WILL BE MID-LEVEL CLOUDS. A WEAK
SURFACE FRONT WILL CHANGE WINDS TO THE NORTH. A TREND TOWARDS HOT
WEATHER STARTS TUESDAY AND LASTS INTO FRIDAY BEFORE A STRONGER
UPPER LEVEL SYSTEM BRINGS STRONGER LIFT ACROSS OKLAHOMA AND A
FRONT MOVES INTO THE STATE. THE MORE HUMID BOUNDARY LAYER THAT
WILL EXIST SHOULD HAVE NO PROBLEM PRODUCING RAIN AND THUNDERSTORMS
LATE FRIDAY AND SATURDAY. COOLER AND DRIER AIR WILL FOLLOW SUNDAY.
09
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 81 58 83 57 / 0 0 0 0
HOBART OK 83 57 85 57 / 0 0 0 0
WICHITA FALLS TX 85 59 88 59 / 0 0 0 0
GAGE OK 84 52 82 55 / 20 0 0 0
PONCA CITY OK 80 57 81 55 / 10 10 0 0
DURANT OK 84 59 88 59 / 0 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
04/09
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1054 AM EDT MON SEP 23 2013
.SYNOPSIS...
UPPER LVL PATTERN WILL FEATURE AN OMEGA BLOCK THRU THIS
WEEK...WITH HIGH PRESSURE RIDGE CENTERED OVER PENNSYLVANIA. BLOCK
WILL LIKELY BREAK DOWN BY LATE NEXT WEEKEND...WHEN A COLD FRONT
WILL APPROACH FROM THE WEST.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
STUBBORN STRATOCUMULUS IS ONCE AGAIN OUR NEMESIS THIS MORNING AS
THE PROMISING BACK CLOUD EDGE DROPPING SOUTH FROM THE FINGERLAKES
HAS NOW FILLED IN BEHIND WITH SHALLOW BUT WIDESPREAD CUMULUS
STREETS FROM THE PA BORDER NORTHWARD THROUGH THE FINGERLAKES AND
LAKE ONTARIO. ADVECTION DOES NOT REVERSE UNTIL AFTER 18Z AND THINK
WE WON`T SEE SUBSTANTIAL CLEARING UNTIL THEREAFTER GIVEN SATELLITE
TRENDS AND WARM ADVECTION DELAYED UNTIL THE MID TO LATE AFTERNOON
HOURS.
NEAR TERM MESO MODELS HAVE HAD GREAT DIFFICULTY SINCE YESTERDAY...
BUT RAP MAY BE DOING THE BEST SHOWING THE THICKEST CLOUD COVER
ERODING FROM SOUTHEAST TO NORTHWEST. THIS DRYING FEATURE CAN
CLEARLY BE SEEN ON THE MORNING VIS LOOP AND SO THE LOWER SUSQ WILL
SEE THE MOST SUN TODAY. THE MID TO LATE AFTERNOON SHOULD BECOME
MOSTLY SUNNY FOR A MAJORITY OF CENTRAL PA AS THE SUBSIDENCE INVERSION
LOWERS/WEAKENS UPON APPROACH OF SFC HIGH. AS PREVIOUSLY MENTIONED...
ENS MEAN 925 MB TEMPS SUPPORT HIGH TEMPS FROM THE UPPER 50S OVR
THE NW MTNS...TO THE UPPER 60S SOUTHEAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
CLEAR SKIES...A CALM WIND AND DRY AIR WILL SET THE STAGE FOR A
COLD NIGHT...WITH AREAS OF FROST LIKELY ACROSS THE N MTNS. SOME OF
THE COLDER VALLEYS WILL LIKELY SEE A FREEZE...BUT NOT SURE
COVERAGE ENOUGH TO WARRANT A FREEZE WARNING. ATTM...GEFS PROBABILITY
GRAPHIC SUGGESTS SUB-FREEZING READINGS WILL BE LOCALIZED...SO HAVE
ISSUED ADVISORY FOR THE HIGH PROB OF FROST AND WILL LET DAY SHIFT
MAKE ANY NECESSARY UPGRADES.
AFTER A CHILLY START WITH LOWS IN THE L30S TO L40S...ABUNDANT
SUNSHINE SHOULD PUSH TEMPS TO SEASONAL LEVELS BY TUE AFTN. GEFS
MEAN 925 TEMPS IMPLY HIGH TEMPS WILL RANGE FROM THE M60S NW
MTNS...TO L70S SUSQ VALLEY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
00Z GEFS AND ECMWF ENSEMBLE DATA BOTH INDICATE PA WILL BE UNDER
RIDGE PORTION OF OMEGA BLOCK...RESULTING IN AN EXTENDED PERIOD OF
FAIR WEATHER LASTING INTO NEXT WEEKEND. GEFS 925/850 TEMPS INDICATE
DAYTIME TEMPS WILL BE NEAR TO A BIT ABV NORMAL...IN PART DUE TO
ABUNDANT SUNSHINE. HOWEVER...DRY AIR AND PROXIMITY OF SFC HIGH
WILL LIKELY PRODUCE SOME COOL MORNINGS. EVENTUAL BREAK DOWN OF BLOCK
WILL LIKELY PUSH A COLD FRONT TOWARD PA LATE IN THE
WEEKEND...ACCOMPANIED BY THE NEXT CHC OF SHOWERS.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
A LAYER OF STRATOCU REMAINS AS COLDER AIR CONTINUES TO ADVECT
INTO THE REGION. CIGS WILL REMAIN ABOVE 3000FT...EXCEPT MVFR CIGS
WILL PERSIST IN UPSLOPE FLOW ACROSS HIGHER ELEVATIONS OF THE NORTH
AND WEST /KBFD TO KJST AND POSS KAOO/.
LINGERING STRATOCU ACROSS THE N AND W WILL DECREASE DURING THE
EARLY AFTERNOON... MARKING THE BEGINNING OF AN EXTENDED PERIOD OF
WIDESPREAD VFR CONDITIONS /EXCEPT FOR SOME PATCHY EARLY MORNING
FOG/.
OUTLOOK...
TUE-FRI...MAINLY VFR...BUT SCT MVFR TO IFR IN AM FOG POSS EACH
DAY...INCREASING LATER IN THE WEEK AS DEWPOINTS RISE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY FROM 3 AM TO 9 AM EDT TUESDAY FOR PAZ004>006-
010-011-037.
&&
$$
SYNOPSIS...FITZGERALD
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD
AVIATION...DEVOIR/RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1050 AM EDT MON SEP 23 2013
.SYNOPSIS...
UPPER LVL PATTERN WILL FEATURE AN OMEGA BLOCK THRU THIS
WEEK...WITH HIGH PRESSURE RIDGE CENTERED OVER PENNSYLVANIA. BLOCK
WILL LIKELY BREAK DOWN BY LATE NEXT WEEKEND...WHEN A COLD FRONT
WILL APPROACH FROM THE WEST.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
STUBBORN STRATOCUMULUS IS ONCE AGAIN OUR NEMESIS THIS MORNING AS
THE PROMISING BACK CLOUD EDGE DROPPING SOUTH FROM THE FINGERLAKES
HAS NOW FILLED IN BEHIND WITH SHALLOW BUT WIDESPREAD CUMULUS
STREETS FROM THE PA BORDER NORTHWARD THROUGH THE FINGERLAKES AND
LAKE ONTARIO. ADVECTION DOES NOT REVERSE UNTIL AFTER 18Z AND THINK
WE WON`T SEE SUBSTANTIAL CLEARING UNTIL THEREAFTER GIVEN SATELLITE
TRENDS AND WARM ADVECTION DELAYED UNTIL THE MID TO LATE AFTERNOON
HOURS.
NEAR TERM MESO MODELS HAVE HAD GREAT DIFFICULTY SINCE YESTERDAY...
BUT RAP MAY BE DOING THE BEST SHOWING THE THICKEST CLOUD COVER
ERODING FROM SOUTHEAST TO NORTHWEST. THIS DRYING FEATURE CAN
CLEARLY BE SEEN ON THE MORNING VIS LOOP AND SO THE LOWER SUSQ WILL
SEE THE MOST SUN TODAY. THE MID TO LATE AFTERNOON SHOULD BECOME
MOSTLY SUNNY FOR A MAJORITY OF CENTRAL PA AS THE SUBSIDENCE INVERSION
LOWERS/WEAKENS UPON APPROACH OF SFC HIGH. AS PREVIOUSLY MENTIONED...
ENS MEAN 925 MB TEMPS SUPPORT HIGH TEMPS FROM THE UPPER 50S OVR
THE NW MTNS...TO THE UPPER 60S SOUTHEAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
CLEAR SKIES...A CALM WIND AND DRY AIR WILL SET THE STAGE FOR A
COLD NIGHT...WITH AREAS OF FROST LIKELY ACROSS THE N MTNS. SOME OF
THE COLDER VALLEYS WILL LIKELY SEE A FREEZE...BUT NOT SURE
COVERAGE ENOUGH TO WARRANT A FREEZE WARNING. ATTM...GEFS PROBABILITY
GRAPHIC SUGGESTS SUB-FREEZING READINGS WILL BE LOCALIZED...SO HAVE
ISSUED ADVISORY FOR THE HIGH PROB OF FROST AND WILL LET DAY SHIFT
MAKE ANY NECESSARY UPGRADES.
AFTER A CHILLY START WITH LOWS IN THE L30S TO L40S...ABUNDANT
SUNSHINE SHOULD PUSH TEMPS TO SEASONAL LEVELS BY TUE AFTN. GEFS
MEAN 925 TEMPS IMPLY HIGH TEMPS WILL RANGE FROM THE M60S NW
MTNS...TO L70S SUSQ VALLEY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
00Z GEFS AND ECMWF ENSEMBLE DATA BOTH INDICATE PA WILL BE UNDER
RIDGE PORTION OF OMEGA BLOCK...RESULTING IN AN EXTENDED PERIOD OF
FAIR WEATHER LASTING INTO NEXT WEEKEND. GEFS 925/850 TEMPS INDICATE
DAYTIME TEMPS WILL BE NEAR TO A BIT ABV NORMAL...IN PART DUE TO
ABUNDANT SUNSHINE. HOWEVER...DRY AIR AND PROXIMITY OF SFC HIGH
WILL LIKELY PRODUCE SOME COOL MORNINGS. EVENTUAL BREAK DOWN OF BLOCK
WILL LIKELY PUSH A COLD FRONT TOWARD PA LATE IN THE
WEEKEND...ACCOMPANIED BY THE NEXT CHC OF SHOWERS.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
A LAYER OF STRATOCU REMAINS AS COLDER AIR CONTINUES TO ADVECT
INTO THE REGION. CIGS WILL REMAIN ABOVE 3000FT...EXCEPT MVFR CIGS
WILL PERSIST IN UPSLOPE FLOW ACROSS HIGHER ELEVATIONS OF THE NORTH
AND WEST /KBFD TO KJST AND POSS KAOO/.
LINGERING STRATOCU ACROSS THE N AND W WILL DIMINISH AFTER SUNRISE
AS NORTHERLY FLOW WEAKENS...MARKING THE BEGINNING OF AN EXTENDED
PERIOD OF WIDESPREAD VFR CONDITIONS /EXCEPT FOR SOME PATCHY
EARLY MORNING FOG/.
OUTLOOK...
TUE-FRI...MAINLY VFR...BUT SCT MVFR TO IFR IN AM FOG POSS EACH
DAY...INCREASING LATER IN THE WEEK AS DEWPOINTS RISE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY FROM 3 AM TO 9 AM EDT TUESDAY FOR PAZ004>006-
010-011-037.
&&
$$
SYNOPSIS...FITZGERALD
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD
AVIATION...RXR
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1053 AM CDT MON SEP 23 2013
.UPDATE...
THE COLD FRONT CURRENTLY EXTENDS ACROSS SOUTH DAKOTA...ALONG A
LINE FROM ABOUT HETTINGER...TO FAITH...TO PINE RIDGE. ALL
ASSOCIATED PRECIPITATION IS POST FRONTAL AT THIS POINT...AND IS
PROGRESSING MUCH SLOWER THAN ORIGINALLY ANTICIPATED. MODELS DO
SHOW A WEAK SURGE IN THE AREAL EXTENT OF PRECIP AS ADDITIONAL UPPER
LEVEL SUPPORT AND INCREASED MID LEVEL FRONTOGENESIS OCCUR THIS
AFTERNOON. HOWEVER...BESIDES THE FAR WESTERN SECTION OF CORSON
COUNTY...THE UPDATED FORECAST DOES NOT HAVE POPS ENTERING INTO OUR
CWA UNTIL THE AFTERNOON HOURS. THE SYSTEM WEAKENS AND THE EASTERN
EXTENT OF PRECIP IS STILL UP IN THE AIR AT THIS POINT. BECAUSE OF
THE DELAYED TIMING...THE EASTERN 2/3 OF THE CWA WILL EXPERIENCE
PRETTY MUCH AN ENTIRE DAY OF SUNSHINE AND WARM AIR
ADVECTION...AND THEREFORE BUMPED UP THE AFTERNOON HIGH
TEMPERATURES SEVERAL DEGREES. THE EASTERN HALF OF THE CWA SHOULD
EXCEED 80 DEGREES TODAY.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TODAY THROUGH WEDNESDAY
WATER VAPOR IMAGERY SHOWS THE UPPER LOW OVER COLORADO EARLY THIS
MORNING. AT THE SURFACE...FRONTAL BOUNDARY IS LOCATED ACROSS
WESTERN SOUTH DAKOTA. SCATTERED SHOWERS HAVE BEEN OCCURRING ACROSS
WESTERN SOUTH DAKOTA AND OVER THE EXTREME NORTHWEST CWA OVER THE
PAST SEVERAL HOURS...BUT RADAR RETURNS ARE DIMINISHING AT THIS
TIME. AHEAD OF THE FRONT...BREEZY/GUSTY SOUTHERLY WINDS CONTINUE
OVER MUCH OF THE CWA WITH TEMPS STILL VERY MILD.
AS THE UPPER LOW KICKS OUT INTO THE PLAINS LATER THIS MORNING...A
REGENERATION OF SHOWERS AND STORMS IS EXPECTED OVER THE WESTERN
DAKOTAS. THE LATEST RUN OF THE HRRR AND THE 00Z NSSL WRF SHOW
WESTERN SOUTH DAKOTA SEEING THE BULK OF THE ACTIVITY THROUGH THE
MORNING HOURS...WITH CENTRAL SOUTH DAKOTA HOLDING OFF UNTIL THE
AFTERNOON. WILL HAVE TO WAIT FOR THE UPPER LOW TO GET CLOSER TO
THE AREA IT APPEARS FOR RAINFALL CHANCES TO INCREASE. 00Z NSSL WRF
INDICATES SHOWER AND THUNDERSTORM ACTIVITY DEVELOPING BETWEEN THE
MISSOURI AND JAMES RIVERS BY AROUND 21Z. ALL MODELS INDICATING
THAT THIS SYSTEM WILL WEAKEN AS IT CONTINUES MOVING EAST...WITH
BAND OF RAINFALL DISSIPATING AND BECOMING MORE WIDELY SCATTERED AS
IT MOVES EAST OF THE JAMES VALLEY. HAVE CONSTRUCTED WX/POP GRIDS
TO REFLECT THIS THINKING AND KEPT HIGHEST POPS OVER THE WESTERN
CWA THROUGHOUT THE DAY.
WITH THE SLOWER MOVEMENT OF THE UPPER LOW AND SURFACE FRONT...HAVE
INCREASED HIGHS A COUPLE DEGREES OVER THE EASTERN CWA WHERE
SOUTHERLY WINDS WILL REMAIN AND 850MB TEMPS STAY THE WARMEST.
SPEAKING OF WINDS...EXPECT ANOTHER WINDY DAY FOR THE EASTERN
COUNTIES...BUT LIKELY STAYING BELOW ADVISORY LEVELS.
TUESDAY AND TUESDAY NIGHT WILL BE QUIET AS A WEAK SURFACE RIDGE
SLIDES EAST OVER THE AREA. LOOK FOR MILD TEMPS AND DRY CONDITIONS.
WINDS BEGIN TO INCREASE AGAIN BY WEDNESDAY AS ANOTHER LOW PRESSURE
SYSTEM DEVELOPS TO THE WEST OF THE REGION.
.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY
MAIN FCST CHALLENGE FACING THE EXTENDED PORTION OF FORECAST
REVOLVES AROUND PCPN CHANCES HEADING INTO THE WEEKEND...AND TEMPS
FOR NEXT WEEKEND.
MODELS CONT TO ADVERTISE A LONG WAVE TROF MOVING INTO THE INTERMTN
STATES TO BEGIN THE EXTENDED FOR THE WEDNESDAY NIGHT PERIOD. GOOD
MID LEVEL WAA AHEAD OF THIS TROF AS INDICATED BY 700HPA THETA-E
FORCING. HOWEVER...BOTH GFS AND LATEST EC SUGGEST SFC WINDS WILL
BE MORE SERLY WHICH TYPICALLY ISN`T A GOOD WARMING WIND FOR THE
CWA. THIS WILL PROBABLY HELP TO TEMPER HIGHS SOMEWHAT FROM WHAT
THEY COULD BE GIVEN A SOUTH OR EVEN SW WIND. THE EC IS A BIT
SLOWER THAN GFS ON ARRIVAL OF PCPN...WAITING UNTIL CLOSER TO 12Z
FRIDAY FOR ONSET. THAT SAID...SINCE STILL LOOKING AT 5 DAYS
OUT...AM CONTENT TO LEAVE ALLBLEND GRID ALONE AND REFINE AS
SHORTER TERM MODELS BEGIN TO COVER THIS TIME FRAME.
WITH COLD FROPA DURING THE DAY FRIDAY WITH PLENTY OF EXPECTED
CLOUD COVER...COOLISH TEMPS FRIDAY/SATURDAY SEEM
REALISTIC...ESPECIALLY WITH BOTH GFS AND EC SHOWING 850HPA TEMPS
IN THE +4C TO +6C RANGE. WAA RETURNS IN EARNEST FOR SUNDAY..SO
FORECAST HIGHS ABOUT A CATEGORY WARMER THAN SATURDAY ALSO SEEMS
PLAUSIBLE.
MODELS CONTINUE TO BE IN RELATIVELY GOOD AGREEMENT ON LONG WAVE
PATTERN. A TROF WILL MOVE OUT OF THE PAC WEST TOWARD THE PLAINS BY
THE END OF THE WORK WEEK. EXACT TIMING AND PRECIP PLACEMENT DIFFER
SLIGHTLY SO STUCK CLOSE TO ALLBLEND. THIS PUTS POPS IN THE
FORECAST THURSDAY NIGHT THROUGH FRIDAY NIGHT...THOUGH TIMING WILL
LIKELY NEED TO BE REFINED AS MODELS GAIN A BETTER GRASP ON THE
SYSTEM.
TEMPERATURES AHEAD OF THE UPPER TROF WILL BE IN THE UPPER 70S.
BEHIND THE TROF TEMPS WILL FALL TO RIGHT AROUND NORMAL FOR LATE
SEPTEMBER.
&&
.AVIATION...
12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
VFR CONDS ARE EXPECTED FOR THE VALID FORECAST PERIOD. AN ELONGATED
TROUGH OF LOW PRESSURE IS LOCATED FROM WESTERN ND INTO LOW
PRESSURE LOCATED IN NERN CO. THIS TROUGH WILL MOVE SLOWLY EAST
THROUGH THE VALID FORECAST PERIOD...WITH ISOLD/SCT -SHRA/-TSRA
POSSIBLE ALONG THE TROUGH. LOOK FOR STRONG SE WINDS TO CONT FOR
THE KATY/KABR TERMINALS THROUGH 00Z TUESDAY. LOOK FOR VCSH CONDS
TO SET UP FOR THE KPIR/KMBG TERMINALS AROUND 00Z TUESDAY. CIGS MAY
LOWER A BIT IN THE HEAVIER SHOWERS...BUT SHOULD REMAIN IN THE VFR
CATEGORY.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...SERR
SHORT TERM...TMT
LONG TERM...HINTZ
AVIATION...HINTZ
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1012 AM CDT MON SEP 23 2013
.UPDATE...SOUTHEASTERLY FLOW ALLOWING LAKE EFFECT LOW STRATUS
CLOUDS OVER THE LAKESHORE COUNTIES TO FILL IN TO BROKEN COVERAGE.
MODELS INDICATE THEY WILL PERSIST THROUGH MIDDAY. TEMPERATURES ARE
RUNNING A FEW DEGREES WARMER THAN YESTERDAY. 925MB TEMPS FORECAST
REACH 11C EAST TO 13-14 C IN SOUTH-CENTRAL WI. AS A RESULT HIGHS
ARE ON TRACK FOR MID 60S IN THE EAST TO AROUND 70 IN SOUTH-CENTRAL
WI.
&&
.AVIATION/18Z TAFS/...LAKE EFFECT CLOUDS CONTINUE TO BRING MVFR
CIGS TO THE EAST THIS MORNING. BASED ON LATEST NAM AND RAP 900 MB
RH...LOOKS LIKE THESE CLOUDS MAY HANG ON THROUGH THE REMAINDER OF
THE MORNING. EVEN IF CLOUDS ARE STILL BKN BY 18Z THOUGH...SHOULD
SEE ENOUGH MIXING BY TO RAISE BASES TO VFR. WILL LIKELY BE QUIET
THEN THROUGH THE REMAINDER OF THE DAY AND OVERNIGHT WITH HIGH
PRESSURE CENTERED OVER THE EASTERN GREAT LAKES.
MAY SEE ANOTHER ROUND OF LAKE EFFECT CLOUDS TOMORROW MORNING WITH
A SIMILAR AIRMASS IN PLACE. THE WIND FLOW LOOKS MORE SOUTHERLY
THAN TODAY THOUGH...SO NOT AS GOOD OF A SETUP AS THIS MORNING.
&&
.PREV DISCUSSION... /ISSUED 307 AM CDT MON SEP 23 2013/
TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH.
A N-S SFC TROUGH AND ACCOMPANIED UPPER TROUGH WILL MOVE EAST
ACROSS THE GREAT PLAINS TODAY...AND TRACK INTO THE LOWER TO
MIDDLE MO RIVER VALLEY LATER TNT. THE UPPER RIDGE OVER WI WILL
SLOWLY MOVE EAST WITH THE SFC RIDGE OVER THE ERN GREAT LAKES. A
SELY FLOW WILL PREVAIL...WITH FCST SOUNDINGS SHOWING THE
POTENTIAL FOR FEW-SCT LAKE EFFECT STRATOCUMULUS CLOUDS IN ERN WI
INCLUDING SOME DAYTIME CUMULUS AS WELL.
BUT FOR THE MOST PART...PLENTY OF SUNSHINE AND WEAK WARM ADVECTION
WILL BOOST 925 MB TEMPS INTO THE LOWER TO MID TEENS CELSIUS WHICH
YIELDS HIGHS IN THE MID TO UPPER 60S. LOW FOR TNT WILL BE A LITTLE
MILDER THAN THIS MORNING...WITH SOME DECOUPLING EXPECTED OVER THE
ERN CWA BUT AWAY FROM THE LAKE.
TUESDAY THROUGH WEDNESDAY NIGHT...FORECAST CONFIDENCE IS HIGH.
SHORT TERM MODELS REMAIN IN GOOD AGREEMENT WITH FEATURES DURING
THIS PERIOD. THEY HAVE THE 500MB SHORTWAVE TROUGH WEAKENING AS IT
SLIDES TO THE EAST SOUTHEAST FROM EASTERN NEBRASKA/WESTERN IOWA TO
CENTRAL INDIANA TUESDAY AND TUESDAY NIGHT. THIS FEATURE TAKES MOST
OF THE MIDDLE TO UPPER LEVEL MOISTURE WITH IT IN THIS
DIRECTION...MAINLY MISSING SOUTHERN WISCONSIN. 500MB RIDGE THEN
BUILDS IN ACROSS THE WESTERN GREAT LAKES REGION WEDNESDAY AND
WEDNESDAY NIGHT.
AT THE SURFACE...HIGH PRESSURE REMAINS NORTHEAST OF THE REGION
TUESDAY INTO WEDNESDAY NIGHT. ALL OF THIS RESULTS IN QUIET WEATHER
CONTINUING THIS TIME. TEMPERATURES WILL CONTINUE TO SLOWLY
WARM...WITH 925MB TEMPERATURES SUPPORTING UPPER 60S TO LOWER 70S
AWAY FROM THE LAKE TUESDAY AND WEDNESDAY. LOWS WILL RISE INTO THE
UPPER 40S AWAY FROM THE LAKE EACH NIGHT...MILDER NEAR THE LAKE.
THURSDAY THROUGH SUNDAY...FORECAST CONFIDENCE IS MEDIUM TO HIGH.
GFS/ECMWF ARE IN FAIR AGREEMENT WITH FEATURES THURSDAY INTO
FRIDAY. THEY SHOW THE 500MB RIDGE SLOWLY SHIFTING EAST OF THE
REGION. SURFACE HIGH PRESSURE WILL REMAIN EAST OF THE
REGION...WITH ITS INFLUENCE STILL OVER THE AREA. QUIET WEATHER
WILL CONTINUE THURSDAY INTO FRIDAY...WITH TEMPERATURES CONTINUING
TO WARM ABOVE SEASONAL NORMALS.
THE GFS CONTINUES TO BE ABOUT 6 HOURS QUICKER WITH THE COLD
FRONTAL PASSAGE OVER THE AREA THAN THE ECMWF SATURDAY/SATURDAY
NIGHT. THE GFS BRINGS IT THROUGH SATURDAY...WITH THE ECMWF
SATURDAY EVENING. BOTH MODELS HAVE PRECIPITATION THROUGH THE AREA
BY 12Z SUNDAY...WITH SUNDAY DRY WITH HIGH PRESSURE MOVING INTO THE
REGION FROM THE WEST. FOR NOW...WILL USE CONSENSUS POPS AND
TEMPERATURES FRIDAY NIGHT INTO SUNDAY.
AVIATION/12Z TAFS/...VFR CONDITIONS WILL PREVAIL TODAY INTO
TUESDAY. HIGH PRESSURE WILL REMAIN OVER THE EASTERN GREAT LAKES
DURING THIS PERIOD. A ESELY FLOW WILL CONTINUE WITH FEW-SCT
STRATOCUMULUS OR CUMULUS CLOUDS OVER ERN WI DUE TO LAKE EFFECT OR
DAYTIME HEATING. OTHERWISE MO CLEAR SKIES ARE EXPECTED.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...SM/DDV
TODAY/TONIGHT AND AVIATION...GEHRING
TUESDAY THROUGH SUNDAY...WOOD
AREA FORECAST DISCUSSION
NWS GOODLAND KS
239 PM MDT MON SEP 23 2013
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 239 PM MDT MON SEP 23 2013
UPPER FLOW WILL BE NORTHWEST TONIGHT AND TUESDAY AS THE UPPER LOW
MOVES NORTHEAST INTO IOWA. SURFACE HIGH PRESSURE WILL MOVE INTO THE
CENTRAL PLAINS.
AS THE UPPER LOW LIFTS OUTS THIS EVENING ANY REMAINING SHOWERS WILL
EXIT THE FA. SUBSIDENCE WILL FOLLOW AND CONTINUE THROUGH TUESDAY.
OTHER THAN SOME SLIGHT CHANCE POPS EARLY THIS EVENING, POPS WILL BE
NIL FOR THE REMAINDER OF THIS PART OF THE FORECAST.
HRRR AND RUC MODELS INDICATE STRONG WINDS WILL CONTINUE UNTIL AROUND
01Z. PLAN TO CONTINUE HIGH WIND WARNING AND WIND ADVISORY UNTIL 01Z
TUESDAY. GUSTY NORTHWEST WIND WILL DECREASE AROUND SUNSET.
MIN TEMPERATURES WILL BE COOL TONIGHT WITH READINGS RANGING FROM THE
MID 40S IN EASTERN COLORADO TO AROUND 50 IN THE EASTERN FA. MAX
TEMPERATURES TUESDAY WILL WARM INTO THE MID/UPPER 70S.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 239 PM MDT MON SEP 23 2013
A BRIEF PERIOD OF SHORTWAVE RIDGING WILL CONTINUE TUESDAY NIGHT INTO
WEDNESDAY...LEADING TO DRY WEATHER. AS STATED ABOVE...BRIEF IS THE
KEY WORD AS THE NEXT LARGE TROUGH OF LOW PRESSURE DEVELOPS OVER THE
WESTERN UNITED STATES AND HEADS EAST. AHEAD OF THE UPPER LEVEL
TROUGH...A WARMING TREND IS FORECAST UNDER A WARM AIR ADVECTION
REGIME OF SOUTH WINDS. HIGH TEMPERATURES ARE EXPECTED TO CLIMB INTO
THE MID 80S ON WEDNESDAY AND MID TO UPPER 80S...POSSIBLY NEAR
90...ON THURSDAY. ALSO...PRESSURE GRADIENTS ARE EXPECTED TO TIGHTEN
ON WEDNESDAY WHICH WILL RESULT IN A PERIOD OF BREEZY TO POSSIBLY
WINDY CONDITIONS DURING THE DAY AND EARLY EVENING. A LEE TROUGH IS
INDICATED BY MODELS TO MOVE IN ON THURSDAY...BRINGING A WIND SHIFT
AND COOLER TEMPERATURES TO NORTHEAST COLORADO. AHEAD OF THE LEE
TROUGH...IT IS POSSIBLE A FEW SHOWERS...POSSIBLY A
THUNDERSTORM...COULD DEVELOP FOR THURSDAY AFTERNOON AND THURSDAY
NIGHT.
AS THE UPPER LEVEL TROUGH EJECTS ACROSS THE NORTHERN PLAINS...A COLD
FRONT WILL BE FORCED DOWN ACROSS THE TRI-STATE AREA. THERE ARE SOME
LARGE TIMING DIFFERENCES BETWEEN MODELS AT THE PRESENT
TIME...LEADING TO WIND AND TEMPERATURE FIELDS LACKING IN AGREEMENT
AS WELL. THEREFORE...DID NOT STRAY TOO MUCH FROM THE MIDDLE GROUND
OF THE MODELS FOR THIS NEXT SYSTEM. THE MIDDLE GROUND PLACES FRONTAL
PASSAGE EARLY IN THE DAY ON FRIDAY. EITHER WAY...THERE WILL BE
A GOOD CHANCE FOR SHOWERS AND POSSIBLY A FEW RUMBLES OF THUNDER FOR
FRIDAY NIGHT BEHIND THE FRONT. A FEW ISOLATED SHOWERS AND STORMS ARE
POSSIBLE AHEAD OF THE FRONT BUT THE MAJORITY OF THE ACTIVITY SHOULD
STAY TO THE SOUTHEAST WHERE INSTABILITY IS PROJECTED TO BE HIGHER.
IN ADDITION...TEMPERATURES COOL DRAMATICALLY AGAIN BEHIND THE COLD
FRONT. HIGH TEMPERATURES ON FRIDAY WILL RANGE FROM THE LOW 60S TO
THE UPPER 70S FROM NORTHWEST TO SOUTHEAST. COOL...NEAR TO JUST BELOW
NORMAL TEMPERATURES WILL CONTINUE INTO THE WEEKEND AS SURFACE HIGH
PRESSURE BUILDS IN FROM THE WEST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1149 AM MDT MON SEP 23 2013
UPPER LOW WILL BRING SHOWERS AND ISOLATED THUNDERSTORMS INTO KGLD
AND KMCK THIS AFTERNOON. SOME MVFR CONDITIONS WILL BE POSSIBLE
WITH THE SHOWERS. THE LOW WILL QUICKLY MOVE OUT BY EVENING WITH
VFR CONDITIONS AND LIGHTER WINDS PREVAILING OVERNIGHT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WIND ADVISORY UNTIL 7 PM MDT /8 PM CDT/ THIS EVENING FOR KSZ001-
013-014-027-028-041-042.
HIGH WIND WARNING UNTIL 7 PM MDT /8 PM CDT/ THIS EVENING FOR
KSZ013-027-028-041-042.
CO...WIND ADVISORY UNTIL 7 PM MDT THIS EVENING FOR COZ090>092.
HIGH WIND WARNING UNTIL 7 PM MDT THIS EVENING FOR COZ091-092.
NE...NONE.
&&
$$
SHORT TERM...FS
LONG TERM...RRH
AVIATION...FS
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1211 PM CDT Mon Sep 23 2013
.SHORT TERM...(Today and Tonight)
Issued at 302 AM CDT MON SEP 23 2013
Water vapor imagery as of 07z depicts the center of the strong upper
shortwave trough across southern Colorado shifting eastward.
Meanwhile an abundant amount of subsidence ahead of the wave was
noted. A frontal boundary stretched across the northern Gulf is
responsible in blocking moisture from spreading northward into the
region. At the surface, observations depict the surface trough
positioned across eastern Colorado with gusty southerly winds
stretching into western Kansas.
As the above mentioned upper wave lifts northeast into the central
plains Monday afternoon, the surface low edges into western Kansas,
gradually increasing southerly wind speeds between 20 and 25 mph
this afternoon. Gusts over 35 mph are expected as deeper mixing and
dry air aloft restrains dewpoints to the low 50s. Daytime heating
combined with convergence along and ahead of a weak cold front
shifting east may trigger scattered convection this afternoon and
evening. The recent runs of the HRRR and 4-KM ARW support this
thinking as north central areas stand to see the best chance of
precipitation. While speed shear is prevalent at 50 kts up to 6 Km,
uncertainty exists as to if the updrafts are able to maintain
themselves and reach the CWA border. Weak instability, mid level
lapse rates around 5-6 degrees C/Km, and meager moisture in place
can only warrant a slight chance mention of showers with perhaps an
isolated thunderstorm through this evening. The upper trough and
precipitation lifts out of the area overnight as the frontal
boundary and associated cloud cover passes through the area dry.
Expect highs today similar to previous afternoons with readings
generally in the upper 70s. By this evening, increasing insulation
from cloud cover and gusty southerly winds will boost low
temperatures a few degrees into the middle 50s.
.LONG TERM...(Tuesday through Sunday)
Issued at 302 AM CDT MON SEP 23 2013
Tuesday through Thursday continues to look dry as forcing from
upper trough moves east of the area and ridging develops. Models
show some weak cold air advection through part of the day
Tuesday. There is also better agreement on some higher 850MB RH
hanging in on the back side of the departing system implying skies
could be partly cloudy over eastern KS. Because of the cooler air
advecting south and east and the potential for a little more
clouds, have trended highs for Tuesday down a degree or two. By
Wednesday morning, skies could clear out with winds becoming light
and variable as a weak surface ridge axis passes over eastern KS
setting up conditions for good radiational cooling. Because of
this have also trended lows Wednesday morning down with some
readings potentially nearing 50. By Thursday the models are in
good agreement that southerly return flow will have begun with
better moisture advecting north. Therefore Highs in the 80s and
lows in the 60s appear reasonable.
For Thursday night through Saturday, the models remain in good
agreement with the overall synoptic pattern with only some slight
timing differences in the frontal passage. However it looks like
the most likely timing is for the front to move through late
Friday night and Saturday morning. If models continue to converge
on this solution, later shifts may want to increase pops to
likely as there appears to be plenty of moisture with modest
instability for the front to come through and lift. With the front
expected to remain north of the area most of the day Friday, temps
are expected to remain above normal with readings in the 80s.
Saturday looks to see the bulk of the cool down as cold air
advection increases through the day.
Precip should be all but over Saturday evening as the front is
progged to be into southeast KS and southern MO. Central and
eastern KS should see clearing skies into Sunday as a modified
pacific surface ridge builds into the plains and mid level heights
gradually rise. WPC tends to favor the more amplified pattern of
the ECMWF for the end of the weekend with a closed low eventually
developing to the east. This will likely keep Fall like temps for
the forecast area on Sunday.
&&
.AVIATION...(For the 18Z TAFs through 18Z Tuesday Afternoon)
Issued at 1205 PM CDT MON SEP 23 2013
Expect VFR conditions through the next 24 hours. Southerly winds
of 14 to 19 KTS with gusts of 23 to 28 KTS will diminish towards
sunset. A wind shift to the northwest will occur between 12Z and
15Z at the terminals. There may be a brief period of SCT-BKN MVFR
ceilings through the mid and late morning hours of Tuesday.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Bowen
LONG TERM...Wolters
AVIATION...Gargan
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
405 PM EDT MON SEP 23 2013
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 405 PM EDT MON SEP 23 2013
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A MID LEVEL RIDGE OVER THE
WRN GREAT LAKES. UPSTREAM...A WELL-DEFINED MID LEVEL LOW WAS LIFTING
NE THRU WRN NEBRASKA. ALTHOUGH THE SFC HIGH PRES RIDGE IS EAST OF
THE AREA...EXTENDING FROM JAMES BAY TO LAKE HURON...STUBBORN
STRATOCU REMAINS DOWNWIND OF LAKE MICHIGAN...THOUGH THERE ARE SIGNS
THAT COVERAGE IS STARTING TO SHRINK DUE TO A COMBINATION OF FALLING
INVERSION HEIGHTS (PER RAOBS TRENDS) AND DAYTIME HEATING MIXING OUT
LOW-LEVEL MOISTURE. WARMING AIR MASS IS ALSO DIMINISHING THE LAKE
COMPONENT TO CLOUD COVER. ABUNDANT SUNSHINE HAS HELPED TO RAISE
TEMPS INTO MID 60S THIS AFTN OVER THE W HALF OF UPPER MI.
ALTHOUGH A WELL-DEFINED SHORTWAVE IS OVER THE WRN PLAINS...SHORT
TERM AND THE NEXT SEVERAL DAYS WILL BE QUIET WEATHER WISE. MAIN FCST
CONCERN WILL BE CLOUD COVER. WITH STRATOCU COVERAGE NEAR LAKE
MICHIGAN SHOWING SIGNS OF SHRINKING...THERE IS HOPE THAT THE CLOUDS
WILL CONTINUE TO DISSIPATE AND NOT REDEVELOP/EXPAND TONIGHT...
ESPECIALLY SINCE INVERSION BASE TEMPS OVER NRN LAKE MICHIGAN WILL BE
A COUPLE OF C HIGHER TONIGHT THAN LAST NIGHT. HOWEVER...SINCE
TRAJECTORIES LEAD SSE BACK TO THE STRATOCU/MOISTURE FIELD OVER SRN
LWR MI/NRN OH...STRATOCU PROBABLY WON`T CLEAR OUT FOR THE ENTIRE
NIGHT. THERE MAY BE A PERIOD THIS EVENING WHEN MUCH OF THE CLOUD
COVER DISSIPATES...BUT EXPECT SOME INCREASE IN STRATOCU AGAIN
OVERNIGHT GIVEN UPSTREAM CLOUD COVER/MOISTURE AS MENTIONED AND DUE
TO LAND BREEZE CONVERGENCE DEVELOPING OVER LAKE MICHIGAN. CLOUDS
SHOULDN`T BE AS EXTENSIVE LATE TONIGHT/TUE MORNING AS EARLIER TODAY.
AS FOR TEMPS...GENERALLY FAVORED THE LOW END OF GUIDANCE WITH
PRECIPITABLE WATER 50-60PCT OF NORMAL AND WEAKER PRES
GRADIENT/LOW-LEVEL WINDS LATER TONIGHT THAN EARLY THIS MORNING. WITH
MINS DOWN INTO THE MID 30S IN THE INTERIOR...EXPECT PATCHY FROST
OVERNIGHT.
MODELS ARE IN GOOD AGREEMENT TAKING THE CURRENTLY WELL-DEFINED MID
LOW OVER NEBRASKA E INTO THE MID MISSISSIPPI VALLEY TUE AND
WEAKENING IT AS IT CUTS INTO THE MID LEVEL RIDGE. FEATURE WILL HAVE
NO AFFECT ON THE WEATHER HERE TUE AS DRY AIR LINGERS OVER THE AREA.
AS WITH TONIGHT...MAIN CONCERN TUE WILL BE STRATOCU NEAR LAKE MI.
STRATOCU DOWNWIND OF THE LAKE MAY BRIEFLY EXPAND WESTWARD FOR A
COUPLE OF HRS TUE MORNING AS DAYTIME HEATING WORKS ON LOW-LEVEL
MOISTURE...BUT THERE SHOULD BE A SOMEWHAT QUICKER EROSION OF THE
CLOUDS FROM INLAND TOWARD THE LAKE THAN TODAY. OTHER THAN THE CLOUD
ISSUE...TUE IS SHAPING UP TO BE A NICE AUTUMN DAY. IF MIXING REACHES
850MB...MAX TEMPS IN THE LOW/MID 70S WOULD BE COMMON. MIXING DEPTH
MAY NOT GET QUITE THAT HIGH...SO UPPER 60S/LWR 70S LOOK MORE LIKELY
AWAY FROM MARINE INFLUENCE.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 249 PM EDT MON SEP 23 2013
WILL START THE PERIOD AT 00Z WEDNESDAY WITH THE 500MB RIDGE STILL
SET UP ACROSS E UPPER MI AND LAKE HURON/E ONTARIO. THE MAIN STORY
WILL BE THE CONTINUALLY WEAKENING TROUGH STRETCHING FROM MN THROUGH
NW TN. A HIGHLY BROKEN LINE OF SHOWERS MAY BE SET UP ACROSS MN...BUT
WITH THE WEAKENING OF THE TROUGH AND SFC HIGH WITH LIGHT NE FLOW AT
THE SFC...LITTLE MORE THAN CLOUDS ARE ANTICIPATED ACROSS UPPER MI
LATE TUESDAY NIGHT INTO WEDNESDAY MORNING. BEHIND THE 500MB
TROUGH...THE S-CENTRAL PLAINS RIDGE WILL QUICKLY BUILD BACK ACROSS
THE UPPER GREAT LAKES WEDNESDAY THROUGH THURSDAY.
LOOK FOR STRONGER SW FLOW TO TAKE OVER ALOFT AT AT THE SFC THURSDAY
NIGHT THROUGH FRIDAY NIGHT...AHEAD OF THE NEARING TROUGH TO OUT W.
COOLER AIRMASS IS ON THE WAY FOR THE WEEKEND. WE CAN GET A GLIMPSE
OF WHAT IS TO COME BY LOOKING AT THE 00Z SATURDAY 850MB TEMPS ACROSS
THE REGION. 850MB TEMPS WILL LIKELY RANGE FROM 14-16Z ACROSS UPPER
MI...WHILE A MUCH COOLER 4-6C ACROSS NW ND. ONLY MINIMAL TS
POTENTIAL ALONG THE FRONT...GIVEN ITS NOCTURNAL PASSAGE OVER THE W
CWA SATURDAY MORNING. THERE ARE ENOUGH SIGNIFICANT DIFFERENCES
BETWEEN THE ECMWF AND GFS AT THIS POINT TO GO WITH A CONSENSUS
SOLUTION. THE 23/12Z RUN OF THE GFS IS AROUND 6HRS FASTER THAN THE
23/00Z ECMWF WITH THE PASSAGE OF THE SHORTWAVE. STILL...THEY ARE
STARTING TO COME TO A BETTER AGREEMENT WHEN COMPARED TO THE MUCH
QUICKER 23/06Z RUN OF THE GFS.
THE ENTIRE SYSTEM LOOKS TO MODERATE QUITE A BIT...WITH THE COOLEST
AIR FILTERING INTO UPPER MI BEING AROUND 5-7C SATURDAY NIGHT THROUGH
MONDAY MORNING. AS AN ASIDE...THE 23/12Z RUN OF THE GFS ONLY HAS
850MB TEMPS COOLING TO AROUND 10C. MUCH OF THIS IS DUE TO THE
DIFFERENCE IN THE HANDLING OF THE MID-UPPER LEVEL WAVE. THE ECMWF IS
PERSISTENT IN HAVING THE TROUGH OVER THE UPPER GREAT LAKES THIS
WEEKEND CUT OFF FROM THE MAIN W-E FLOW AND FORM A LOW
OVERHEAD...BEFORE DROPPING IT INTO THE MID MS VALLEY THROUGH THE
MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 127 PM EDT MON SEP 23 2013
VFR CONDITIONS SHOULD PREVAIL AT KIWD/KCMX/KSAW THRU THIS FCST
PERIOD UNDER A GENERALLY DRY AIR MASS ASSOCIATED WITH HIGH PRES OVER
ONTARIO/WRN QUEBEC. HOWEVER...THERE IS SOME CONCERN THAT LOW CLOUDS
COULD DEVELOP AT KSAW LATE TONIGHT UNDER SSE UPSLOPE FLOW OFF LAKE
MICHIGAN. SINCE CURRENT DWPTS OVER NRN LAKE MICHIGAN AREN`T
SIGNIFICANTLY HIGHER THAN EXPECTED MIN TEMPS TONIGHT...WILL HOLD OFF
ON INCLUDING A LOW MVFR OR EVEN IFR CIG AT KSAW FOR NOW. WILL BE
SOMETHING TO MONITOR. UNDER TIGHTER PRES GRADIENT...MARGINAL LLWS IS
EXPECTED AT KIWD TONIGHT AS WINDS INCREASE ABOVE NOCTURNAL
INVERSION.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 405 PM EDT MON SEP 23 2013
SLOW MOVING WEATHER PATTERN THIS WEEK WILL FEATURE HIGH PRES TO THE
E AND LOW PRES TO THE W. EVENTUALLY...A LOW PRES SYSTEM WILL MOVE NE
TO HUDSON BAY LATE WEEK WITH ASSOCIATED COLD FRONT PASSING ACROSS
LAKE SUPERIOR SAT. THRU THE WEEK...RELATIVELY WEAK PRES GRADIENT
WILL RESULT IN WINDS MOSTLY UNDER 20KT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1241 PM EDT MON SEP 23 2013
.SYNOPSIS...
ISSUED AT 249 AM EDT MON SEP 23 2013
HIGH PRESSURE WILL BRING AN EXTENDED PERIOD OF DRY WEATHER AND
MOSTLY CLEAR SKIES THROUGH THE WORK WEEK. HIGH TEMPERATURES WILL
SLOWLY MODERATE...WITH READINGS WELL ABOVE NORMAL WEDNESDAY THROUGH
SATURDAY. OVERNIGHT LOWS WILL BE COOL...AND FROST REMAINS A
POSSIBILITY IN MANY AREAS AGAIN TONIGHT.
&&
.UPDATE...
ISSUED AT 1240 PM EDT MON SEP 23 2013
15Z COMPOSITE ANALYSIS SHOWS A 1024MB HIGH OVER NORTHEAST ONTARIO...
WITH SHARP MID/UPPER LEVEL RIDGING SPANNING THE LENGTH OF THE
MISSISSIPPI VALLEY. OVERALL AIR MASS IS QUITE DRY WITH 12Z APX
SOUNDING PRECIPITABLE WATER OF 0.35 INCH...BUT SHALLOW INSTABILITY
OVER LAKES MICHIGAN/HURON (WITH WELL DEFINED LAND BREEZE BOUNDARY
OUT OVER LAKE HURON) PRODUCING CLOUDS ACROSS NORTHEAST LOWER AND
PARTS OF EASTERN UPPER...SOME OF WHICH ARE BEING ENHANCED BY THE
DIURNAL HEATING CYCLE. SKIES OVER NORTHWEST LOWER WERE SUNNY.
DEEP LAYER RIDGING GOING NOWHERE FAST THIS AFTERNOON. CLOUDS ACROSS
EASTERN UPPER/NORTHEAST LOWER EXPECTED TO GRADUALLY MIX OUT WITH
TIME...HAVE MADE SOME ADJUSTMENT TO SKY COVER ESPECIALLY ACROSS
EASTERN UPPER. MIXING 12Z APX SOUNDING TO 850MB YIELDS AN AFTERNOON
HIGH OF 62F...SO AROUND 60-MID 60S SHOULD WORK MOST AREAS.
UPDATE ISSUED AT 804 AM EDT MON SEP 23 2013
UPDATE TO EXPIRE FROST/FREEZE HEADLINES.
UPDATE ISSUED AT 713 AM EDT MON SEP 23 2013
CLOUD COVER HAS EXPANDED A BIT FURTHER INTO NE LOWER MI...THOUGH
THAT EXPANSION HAS STALLED OVER THE LAST 60-90MIN. THIS PROMISES
ADDITIONAL EROSION...ESPECIALLY AS THE SUN GOES TO WORK.
STILL...HAVE TENDED TO SLOW DOWN CLEARING TRENDS THIS MORNING.
OTHER AREAS IMPACTED BY AT LEAST PARTLY CLOUDY CONDITIONS THIS
MORNING INCLUDE WESTERN MACK AND FAR WESTERN CHIP...AND
GLADWIN/ARENAC COUNTIES.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 249 AM EDT MON SEP 23 2013
LARGE CANADIAN HIGH PRESSURE SLIDES INTO THE EASTERN LAKES THROUGH
TONIGHT WITH DEVELOPING WEAK RETURN FLOW ACROSS NORTHERN
MICHIGAN. SENSIBLE WEATHER CONCERNS IN THE SHORT TERM FOCUSED
PRIMARILY ON CLOUD TRENDS AND MIN TEMPERATURES TONIGHT.
TODAY...LOW LEVEL FLOW VEERS SOUTHEAST ON WESTERN PERIPHERY OF HIGH
PRESSURE WITH STRENGTHENING WARM AIR ADVECTION PUSHING H8
TEMPERATURES INTO THE +7C TO +9C RANGE. BRINGING THESE TEMPS DOWN
DRY ADIABATICALLY YIELDS HIGHS IN THE UPPER 50S TO MID 60S
/WARMEST WEST/. TRICKY CLOUD FORECAST WITH PLENTY OF RESIDUAL LOW
LEVEL MOISTURE ALONG THE LAKE HURON COAST/SAGINAW BAY TRAPPED
BENEATH SUBSIDENCE INVERSION WITH FAVORABLE DELTA T/S AND WEAK
ONSHORE FLOW. THE RUC 925-850MB RH FIELDS SHOW THESE LOWER CLOUDS
PLAGUING LAKE HURON COASTAL AREAS FROM ALPENA SOUTHWARD TOWARD SAGINAW
BAY THROUGH THE MORNING HOURS. AS DELTA T/S DECREASE WITH WARMING
ALOFT AND MUCH DRIER AIR WORKS INTO THE AREA /PWATS AROUND
0.4/...THE CLOUDS SHOULD /HOPEFULLY/ DISSIPATE. AS IS FREQUENTLY
THE CASE THIS TIME OF YEAR WITH REGARD TO LOW CLOUDS...WOULD NOT
BE SURPRISED IF THEY ENDED UP MORE PERSISTENT THAN CURRENTLY
FORECAST.
TONIGHT...ANOTHER POTENTIAL FROSTY NIGHT FOR PORTIONS OF THE AREA.
EXCELLENT RADIATIONAL COOLING SCENARIO ONCE AGAIN WITH CLEAR SKIES
AND LIGHT WINDS. SEE LITTLE REASON WHY LOW TEMPS WILL NOT DIP INTO
THE MIDDLE 30S OVER PORTIONS OF NORTHERN LOWER /ESPECIALLY EAST OF
I-75/...WITH SOME READINGS LIKELY INTO THE LOWER 30S IN THE
TYPICALLY COLDER LOCATIONS. WILL "BEEF UP" THE FROST WORDING IN
THE HWO...BUT WILL LEAVE HEADLINE DECISIONS TO THE DAY SHIFT BASED
ON LATEST OBS/MODEL TRENDS. AREAS OF FOG ALSO LIKELY...PARTICULARLY
IN THE COLDER VALLEY LOCATIONS AND AROUND INLAND LAKES.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 249 AM EDT MON SEP 23 2013
A SPECTACULAR WORK WEEK IS AHEAD (HARD TO IMAGINE A MULTI-DAY
STRETCH WITH QUIETER LONG-TERM FORECASTS THAN THE LAST FEW). THE ONE
INCOMING SYSTEM OF ANY NOTE IS A VIGOROUS SHORTWAVE IN THE 4-CORNERS
REGION EARLY THIS MORNING. THIS SYSTEM WILL EMERGE INTO THE CENTRAL
PLAINS TODAY...BUT THEN ENCOUNTER A BLOCKED PATTERN TO THE EAST...
WITH A STALLED UPPER LOW OVER NEW BRUNSWICK AND RIDGING IN THE
LAKES. THE INCOMING WAVE/S SOLUTION TO THIS PROBLEM IS CUT
UNDERNEATH THE RIDGE...MOVING THRU THE OHIO VALLEY ON WEDNESDAY.
THAT WILL BE TOO FAR SOUTH TO HAVE MUCH IMPACT ON US. THAT LEAVES
TEMPS AS THE ONLY CONCERN OF NOTE.
TUESDAY INTO WEDNESDAY...500MB RIDGING...WHICH IS OVERHEAD TO START
TUE MORNING...WILL DRIFT EAST TO LAKE HURON THRU TUE NIGHT. AS THE
UPPER LOW PASSES TO OUR SOUTH...THAT RIDGE WILL BE DISRUPTED...BUT
RIDGING WILL BEGIN TO FOLD OVER TOP OF THE LOW AND POKE IN FROM THE
SW ON WEDNESDAY. AT THE SURFACE...HIGH PRESSURE WILL BE A SEMI-
PERMANENT FEATURE IN THE VICINITY OF LAKE HURON. THIS PERSISTENT
RIDGING SURFACE AND ALOFT WILL MAINTAIN DEEP SUBSIDENCE AND ABUNDANT
DRY AIR. 850-700MB RH LEVELS ARE BELOW 20 PERCENT THROUGHOUT...AND
ARE BELOW 10 PERCENT MOST OF THE TIME.
THE UPPER LOW PASSING TO OUR SOUTH WILL LIKELY FEED SOME THIN CIRRUS
OVERHEAD TUE NIGHT/WED. OTHERWISE...SKIES WILL BE CLEAR. MAX TEMPS
WILL BE MAINLY IN THE MID TO UPPER 60S BOTH DAYS...WITH A FEW 70S
POSSIBLE WEDNESDAY. MIN TEMPS 40-45 FOR MOST...BUT THE INLAND COOL
SPOTS WILL LOWER INTO THE MID/UPPER 30S.
REST OF THE FORECAST...500MB RIDGING GETS PUMPED BACK INTO THE
REGION FROM THE SW FOR THE REST OF THE WORK WEEK. THU/FRI LOOK VERY
PLEASANT AND MILD...WITH MAX TEMPS MAINLY IN THE 70S.
THE GFS REMAINS A FAST OUTLIER WHEN IT COMES TO BREAKING DOWN THE
RIDGE...AND USHERING IN OUR NEXT CHANCE FOR PRECIP. THE ECMWF HAS
BEEN MUCH MORE CONSISTENT...AND IS PREFERRED. HEIGHTS WILL BE
STEADILY ERODED THIS WEEKEND...WITH THE ACTUAL TROF AXIS ARRIVING
MOST LIKELY ON SUNDAY. THIS SUPPORTS DRY WX INTO FRIDAY NIGHT...AND
CHANCE POPS SAT THRU SUNDAY. SATURDAY WILL REMAIN WARM...WITH
READING CLOSER TO CLIMO SUNDAY.
THOUGH IT LIES BEYOND THE SCOPE OF THIS FORECAST...DIFFICULT TO TELL
HOW LONG THE UNSETTLED WX WILL LAST. 12Z ECMWF WANTED TO LINGER THE
TROF IN THE REGION LONG ENOUGH TO REINFORCE IT WITH ARCTIC
ENERGY...CARVING OUT AN UNPLEASANT UPPER LOW OVER THE LAKES REGION
NEXT WEEK. WE SHALL SEE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 713 AM EDT MON SEP 23 2013
VFR.
HIGH PRESSURE CENTERED OVER NE ONTARIO WILL DRIFT SOUTH TO LAKE
HURON OVER THE NEXT 24 HOURS. THE STILL COOL AIRMASS ASSOCIATED
WITH THE HIGH IS SUPPORTING SOME LAKE-INDUCED CLOUD COVER...
ESPECIALLY INTO NE LOWER MI (APN). THIS WILL ERODE WITH TIME TODAY
AS WE WARM. SKIES SHOULD BE CLEAR ACROSS THE AREA TONIGHT. WINDS
WILL BE LIGHT AND VARIABLE.
&&
.MARINE...
ISSUED AT 249 AM EDT MON SEP 23 2013
A LARGE AREA OF HIGH PRESSURE WILL ANCHORED ACROSS THE GREAT LAKES
FOR THE NEXT SEVERAL DAYS. WITH AN OVERALL LIGHT WIND REGIME...NO
HEADLINES ARE ANTICIPATED.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JPB
SYNOPSIS...JZ
SHORT TERM...JK
LONG TERM...JZ
AVIATION...JZ
MARINE...JK
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
641 PM EDT MON SEP 23 2013
.SYNOPSIS...
LARGE AREA OF CANADIAN HIGH PRESSURE CENTERED OVER THE GREAT LAKES
WILL REMAIN NEARLY STATIONARY THROUGH LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
A SURFACE RIDGE CONTINUES TO BUILD IN. THE BIG QUESTION IS HOW
COLD WILL IT GET AND HOW MUCH FROST WILL FORM. AT THIS TIME THE
CLOUDS ARE DEFINITELY ON THE DECREASE. THE HRRR AND MOST OF THE
MODELS INDICATE THAT MOST AREAS WILL BECOME MOSTLY
CLEAR...HOWEVER...SOME CLOUDS WILL LINGER OR REDEVELOP OVER THE
EXTREME NORTHWEST. THE MAIN AREA OF CONCERN FOR FROST IS IN THE
EAST. HAVE MADE NO CHANGES TO THE FROST ADVISORY OVER INLAND
AREAS OF NW PA AND EXTREME NE OH. OVER THE CENTRAL HIGHLANDS WILL
CONTINUE WITH PATCHY FROST. USED A BLEND OF GUIDANCE FOR THE
LOWS. WILL WATCH TO SEE WHETHER FROST NEEDS TO BE ADDED TO MORE
AREAS AND WHETHER THE ADVISORY NEEDS TO BE EXPANDED.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
THE RIDGE WILL BE NORTH TO SOUTH ACROSS THE AREA THROUGH THURSDAY
AND THEN IT WILL SLOWLY SHIFT TO THE EAST. ON TUESDAY MOSTLY SUNNY
SKIES EXCEPT NEAR TOLEDO. AN UPPER LOW WILL MOVE ACROSS THE OHIO
VALLEY TUESDAY NIGHT INTO WEDNESDAY EVENING. THE MAIN AFFECT FROM
THIS SYSTEM WILL BE SOME CIRRUS. WILL GO FOR PARTLY CLOUDY.
OTHERWISE MOSTLY CLEAR OR MOSTLY SUNNY. USED A BLEND OF GUIDANCE
FOR THE TEMPERATURE FORECAST.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
HIGH AMPLITUDE RIDGE ALOFT BUILDS OVER THE GREAT LAKES ON FRIDAY.
SURFACE HIGH PRESSURE WILL BE OVER THE EASTERN GREAT LAKES WITH AN
EASTERLY LOW LEVEL FLOW. EXPECTING TEMPERATURES TO CLIMB ABOVE
NORMAL INTO THE MID 70S MOST AREAS WITH FULL SUN. THE FLOW BACKS
AROUND TO MORE SOUTHERLY ON SATURDAY AS THE SURFACE HIGH SHIFTS
TOWARDS THE EAST COAST WITH ABOVE NORMAL TEMPERATURES MAKING A RUN
AT 80 DEGREES IN THE WEST.
THE NEXT TROUGH WILL LIFT OUT OF THE PLAINS TOWARDS THE AREA ON
SUNDAY. THE GFS WHICH HAS OFFERED A FASTER AND MORE PROGRESSIVE
SOLUTION IS SHOWING SIGNS OF SLOWING DOWN WITH A DEEPER
TROUGH...MORE IN LINE WITH THE ECMWF AND GEM. REMOVED THE LOW POP
FROM SATURDAY NIGHT IN THE EASTERN COUNTIES WITH A CHANCE OF SHOWERS
STILL IN THE FORECAST FOR SUNDAY AND SUNDAY NIGHT. POPS MAY NEED TO
BE SLOWED DOWN FURTHER GIVEN THE DEPTH OF THE WESTERN TROUGH WITH
SOME POTENTIAL FOR THE UPPER LOW TO CLOSE OFF OVER THE FOUR CORNERS
REGION.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
STRATOCU DECK HOLDING FIRM ACROSS THE AREA WITH CLOUDS SLOWLY
SCATTERING OUT TO OUR NORTHEAST. A SIZABLE GAP IS ALSO IN PLACE
ACROSS WESTERN LAKE ERIE. CEILINGS ARE ACTUALLY LOWERING IN SOME
AREAS AS SUBSIDENCE INCREASES WITH A STRENGTHENING SURFACE HIGH TO
OUR NORTH. EXPECTING CLOUD HEIGHTS IN THE 2500-4000 FOOT RANGE TO
PERSIST FOR MOST OF THE AFTERNOON WITH CLOUDS SLOWLY ERODING
AROUND THE FRINGES. SKIES ARE EXPECTED TO BE MOSTLY CLEAR BY
00-02Z ALTHOUGH SOME UNCERTAINTY EXISTS IN TIMING AT EACH SITE.
VFR CONDITIONS THEN EXPECTED FOR THE DURATION OF THE TAF CYCLE
EXCEPT AT TOL WHERE A STRATOCU DECK MAY ONCE AGAIN DEVELOP OFF OF
LAKE ERIE LATE TONIGHT. A LIGHT NORTHEAST FLOW THIS AFTERNOON WILL
BECOME NEARLY CALM OVERNIGHT.
OUTLOOK...VFR.
&&
.MARINE...
GOOD MARINE CONDITIONS EXPECTED THIS WEEK WITH HIGH PRESSURE
REMAINING NEARLY STATIONARY OVER THE EASTERN GREAT LAKES. A LIGHT
NORTHEASTERLY FLOW WILL INCREASE SLIGHTLY ON WEDNESDAY AS A WEAK
SYSTEM MOVES THROUGH THE LOWER OHIO VALLEY. THE HIGH WILL STRENGTHEN
AGAIN FOR THE END OF THE WEEK BEFORE SHIFTING TOWARDS THE EAST
COAST. WINDS WILL GENERALLY BE 10 KNOTS OR LESS WITH WAVES OF 2 FEET
OR LESS.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...FROST ADVISORY FROM 3 AM TO 9 AM EDT TUESDAY FOR OHZ013-014-
022-023-033.
PA...FROST ADVISORY FROM 3 AM TO 9 AM EDT TUESDAY FOR PAZ002-003.
MARINE...NONE.
&&
$$
SYNOPSIS...KIELTYKA
NEAR TERM...KIELTYKA/OUDEMAN
SHORT TERM...KIELTYKA
LONG TERM...KEC
AVIATION...KEC
MARINE...KEC
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
346 PM EDT MON SEP 23 2013
.SYNOPSIS...
LARGE AREA OF CANADIAN HIGH PRESSURE CENTERED OVER THE GREAT LAKES
WILL REMAIN NEARLY STATIONARY THROUGH LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
A SURFACE RIDGE CONTINUES TO BUILD IN. THE BIG QUESTION IS WHEN WILL
IT CLEAR AND THEN HOW COLD WILL IT GET AND HOW MUCH FROST WILL
FORM. AT THIS TIME THE TREND AND MODELS AGREE THAT THE CLOUDS WILL
DECREASE FROM THE NORTHEAST. THE HRRR AND MOST OF THE MODELS
INDICATE THAT MOST AREAS WILL BECOME MOSTLY CLEAR...HOWEVER...SOME
CLOUDS WILL LINGER OR REDEVELOP OVER THE EXTREME NORTHWEST. THE MAIN
AREA OF CONCERN FOR FROST IS IN THE EAST. WILL GO WITH AN ADVISORY
OVER INLAND AREAS OF NW PA AND EXTREME NE OH. OVER THE CENTRAL
HIGHLANDS WILL GO WITH PATCHY FROST. USED A BLEND OF GUIDANCE FOR
THE LOWS. THE NEXT SHIFT WILL HAVE TO WATCH WHETHER FROST NEEDS TO
BE ADDED TO MORE AREAS AND WHETHER THE ADVISORY NEEDS TO BE
EXPANDED.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
THE RIDGE WILL BE NORTH TO SOUTH ACROSS THE AREA THROUGH THURSDAY
AND THEN IT WILL SLOWLY SHIFT TO THE EAST. ON TUESDAY MOSTLY SUNNY
SKIES EXCEPT NEAR TOLEDO. AN UPPER LOW WILL MOVE ACROSS THE OHIO
VALLEY TUESDAY NIGHT INTO WEDNESDAY EVENING. THE MAIN AFFECT FROM
THIS SYSTEM WILL BE SOME CIRRUS. WILL GO FOR PARTLY CLOUDY.
OTHERWISE MOSTLY CLEAR OR MOSTLY SUNNY. USED A BLEND OF GUIDANCE
FOR THE TEMPERATURE FORECAST.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
HIGH AMPLITUDE RIDGE ALOFT BUILDS OVER THE GREAT LAKES ON FRIDAY.
SURFACE HIGH PRESSURE WILL BE OVER THE EASTERN GREAT LAKES WITH AN
EASTERLY LOW LEVEL FLOW. EXPECTING TEMPERATURES TO CLIMB ABOVE
NORMAL INTO THE MID 70S MOST AREAS WITH FULL SUN. THE FLOW BACKS
AROUND TO MORE SOUTHERLY ON SATURDAY AS THE SURFACE HIGH SHIFTS
TOWARDS THE EAST COAST WITH ABOVE NORMAL TEMPERATURES MAKING A RUN
AT 80 DEGREES IN THE WEST.
THE NEXT TROUGH WILL LIFT OUT OF THE PLAINS TOWARDS THE AREA ON
SUNDAY. THE GFS WHICH HAS OFFERED A FASTER AND MORE PROGRESSIVE
SOLUTION IS SHOWING SIGNS OF SLOWING DOWN WITH A DEEPER
TROUGH...MORE IN LINE WITH THE ECMWF AND GEM. REMOVED THE LOW POP
FROM SATURDAY NIGHT IN THE EASTERN COUNTIES WITH A CHANCE OF SHOWERS
STILL IN THE FORECAST FOR SUNDAY AND SUNDAY NIGHT. POPS MAY NEED TO
BE SLOWED DOWN FURTHER GIVEN THE DEPTH OF THE WESTERN TROUGH WITH
SOME POTENTIAL FOR THE UPPER LOW TO CLOSE OFF OVER THE FOUR CORNERS
REGION.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
STRATOCU DECK HOLDING FIRM ACROSS THE AREA WITH CLOUDS SLOWLY
SCATTERING OUT TO OUR NORTHEAST. A SIZABLE GAP IS ALSO IN PLACE
ACROSS WESTERN LAKE ERIE. CEILINGS ARE ACTUALLY LOWERING IN SOME
AREAS AS SUBSIDENCE INCREASES WITH A STRENGTHENING SURFACE HIGH TO
OUR NORTH. EXPECTING CLOUD HEIGHTS IN THE 2500-4000 FOOT RANGE TO
PERSIST FOR MOST OF THE AFTERNOON WITH CLOUDS SLOWLY ERODING
AROUND THE FRINGES. SKIES ARE EXPECTED TO BE MOSTLY CLEAR BY
00-02Z ALTHOUGH SOME UNCERTAINTY EXISTS IN TIMING AT EACH SITE.
VFR CONDITIONS THEN EXPECTED FOR THE DURATION OF THE TAF CYCLE
EXCEPT AT TOL WHERE A STRATOCU DECK MAY ONCE AGAIN DEVELOP OFF OF
LAKE ERIE LATE TONIGHT. A LIGHT NORTHEAST FLOW THIS AFTERNOON WILL
BECOME NEARLY CALM OVERNIGHT.
OUTLOOK...VFR.
&&
.MARINE...
GOOD MARINE CONDITIONS EXPECTED THIS WEEK WITH HIGH PRESSURE
REMAINING NEARLY STATIONARY OVER THE EASTERN GREAT LAKES. A LIGHT
NORTHEASTERLY FLOW WILL INCREASE SLIGHTLY ON WEDNESDAY AS A WEAK
SYSTEM MOVES THROUGH THE LOWER OHIO VALLEY. THE HIGH WILL STRENGTHEN
AGAIN FOR THE END OF THE WEEK BEFORE SHIFTING TOWARDS THE EAST
COAST. WINDS WILL GENERALLY BE 10 KNOTS OR LESS WITH WAVES OF 2 FEET
OR LESS.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...FROST ADVISORY FROM 3 AM TO 9 AM EDT TUESDAY FOR OHZ013-014-
022-023-033.
PA...FROST ADVISORY FROM 3 AM TO 9 AM EDT TUESDAY FOR PAZ002-003.
MARINE...NONE.
&&
$$
SYNOPSIS...KIELTYKA
NEAR TERM...KIELTYKA
SHORT TERM...KIELTYKA
LONG TERM...KEC
AVIATION...KEC
MARINE...KEC
AREA FORECAST DISCUSSION
NWS NORMAN OK
1203 PM CDT MON SEP 23 2013
.UPDATE...
ONLY CHANGE TO GOING FORECAST PACKAGE WAS TO INCREASE WIND SPEEDS
THROUGH THE AFTERNOON AHEAD OF WEAK FRONTAL BOUNDARY. SOUTHERLY
WINDS GUSTING 30 TO 40 MPH WILL REMAIN POSSIBLE ACROSS MAINLY
NORTHWEST OKLAHOMA THROUGH ABOUT 3 OR 4 PM.
&&
.PREV DISCUSSION... /ISSUED 637 AM CDT MON SEP 23 2013/
UPDATE...
REMOVED POPS ACROSS NORTHWESTERN OKLAHOMA THIS MORNING.
DISCUSSION...
ANY SHOWER/ISOLATED THUNDER ACTIVITY ACROSS THE PANHANDLES HAS
LIFTED NORTH/NORTHEAST INTO FAR SOUTHWESTERN KANSAS. DO NOT EXPECT
ANY SHOWERS TO IMPACT FAR NORTHWESTERN OKLAHOMA THIS MORNING.
JTK
PREV DISCUSSION... /ISSUED 554 AM CDT MON SEP 23 2013/
AVIATION...
VFR CONDITIONS ARE EXPECTED. GUSTY SOUTH WIND IN WESTERN OKLAHOMA
WILL GIVE WAY TO LIGHT NORTH WINDS BEHIND A WEAK FRONT OVERNIGHT.
PREV DISCUSSION... /ISSUED 507 AM CDT MON SEP 23 2013/
UPDATE...
UPDATED POPS FOR THIS MORNING...
DISCUSSION...
REMOVED POPS FROM 11Z TO 12Z PER RADAR ANALYSIS OF ONGOING
SHOWERS ACROSS CENTRAL TX/OK PANHANDLES BEST FOCUS FOR DEVELOPMENT
THIS MORNING REMAINS JUST EAST OF THE WEAK SFC FRONT...WHICH
CURRENTLY EXTENDS FROM WRN KS THROUGH ERN NM. WV SAT SHOWS THE
PRIMARY UPPER LOW LIFTING N/NE OFF THE NRN CO FRONT RANGE...WITH
BETTER FOCUS FOR PRECIP ACROSS ERN CO/WRN KS INTO SWRN NE. WITH
THE CURRENT TRACK OF THE SFC LOW ACROSS E. CENTRAL CO AND THE
PARENT 500MB LOW...WOULD NOT BE SURPRISED IF SHOWERS THIS MORNING
JUST SKIRT FAR NWRN OK...OR MISS COMPLETELY. 07Z RUN OF THE HRRR
SUPPORTS THE LATTER SOLUTION...WITH SHOWERS LIFTING NORTH ACROSS
THE OK PANHANDLE INTO SWRN KS MISSING NWRN OK COMPLETELY.
HOWEVER... THIS SOLUTION HAS THE SRN TERMINUS OF CONVECTION
FARTHER NORTH THAN CURRENTLY OBSERVED. WILL CONTINUE TO RUN WITH
SLIGHT CHANCE POPS ACROSS FAR NWRN OK THROUGH 14Z...AS ENSEMBLE
RUNS OF THE HRRR AND SOLUTIONS FROM THE NSSL AND OUN WRF CLIP FAR
NWRN OK WITH A SHOWER OR TWO THROUGH 14Z.
JTK
PREV DISCUSSION... /ISSUED 355 AM CDT MON SEP 23 2013/
DISCUSSION...
AN UPPER TROUGH MOVING QUICKLY INTO THE CENTRAL PLAINS FROM THE
WEST WILL PASS ACROSS NORTHERN OKLAHOMA TODAY. MODELS, RADAR, AND
SATELLITE TRENDS EACH SUGGEST THAT NEARLY ALL RAIN WILL PASS NORTH
OF OKLAHOMA. THE MAIN EFFECT WILL BE MID-LEVEL CLOUDS. A WEAK
SURFACE FRONT WILL CHANGE WINDS TO THE NORTH. A TREND TOWARDS HOT
WEATHER STARTS TUESDAY AND LASTS INTO FRIDAY BEFORE A STRONGER
UPPER LEVEL SYSTEM BRINGS STRONGER LIFT ACROSS OKLAHOMA AND A
FRONT MOVES INTO THE STATE. THE MORE HUMID BOUNDARY LAYER THAT
WILL EXIST SHOULD HAVE NO PROBLEM PRODUCING RAIN AND THUNDERSTORMS
LATE FRIDAY AND SATURDAY. COOLER AND DRIER AIR WILL FOLLOW SUNDAY.
09
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 81 58 83 57 / 0 0 0 0
HOBART OK 83 57 85 57 / 0 0 0 0
WICHITA FALLS TX 85 59 88 59 / 0 0 0 0
GAGE OK 84 52 82 55 / 10 0 0 0
PONCA CITY OK 80 57 81 55 / 10 10 0 0
DURANT OK 84 59 88 59 / 0 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
03/11
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1228 PM CDT MON SEP 23 2013
.UPDATE...
SEE UPDATED AVIATION DISCUSSION BELOW.
THE COLD FRONT CURRENTLY EXTENDS ACROSS SOUTH DAKOTA...ALONG A
LINE FROM ABOUT HETTINGER...TO FAITH...TO PINE RIDGE. ALL
ASSOCIATED PRECIPITATION IS POST FRONTAL AT THIS POINT...AND IS
PROGRESSING MUCH SLOWER THAN ORIGINALLY ANTICIPATED. MODELS DO
SHOW A WEAK SURGE IN THE AREAL EXTENT OF PRECIP AS ADDITIONAL UPPER
LEVEL SUPPORT AND INCREASED MID LEVEL FRONTOGENESIS OCCUR THIS
AFTERNOON. HOWEVER...BESIDES THE FAR WESTERN SECTION OF CORSON
COUNTY...THE UPDATED FORECAST DOES NOT HAVE POPS ENTERING INTO OUR
CWA UNTIL THE AFTERNOON HOURS. THE SYSTEM WEAKENS AND THE EASTERN
EXTENT OF PRECIP IS STILL UP IN THE AIR AT THIS POINT. BECAUSE OF
THE DELAYED TIMING...THE EASTERN 2/3 OF THE CWA WILL EXPERIENCE
PRETTY MUCH AN ENTIRE DAY OF SUNSHINE AND WARM AIR
ADVECTION...AND THEREFORE BUMPED UP THE AFTERNOON HIGH
TEMPERATURES SEVERAL DEGREES. THE EASTERN HALF OF THE CWA SHOULD
EXCEED 80 DEGREES TODAY.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TODAY THROUGH WEDNESDAY
WATER VAPOR IMAGERY SHOWS THE UPPER LOW OVER COLORADO EARLY THIS
MORNING. AT THE SURFACE...FRONTAL BOUNDARY IS LOCATED ACROSS
WESTERN SOUTH DAKOTA. SCATTERED SHOWERS HAVE BEEN OCCURRING ACROSS
WESTERN SOUTH DAKOTA AND OVER THE EXTREME NORTHWEST CWA OVER THE
PAST SEVERAL HOURS...BUT RADAR RETURNS ARE DIMINISHING AT THIS
TIME. AHEAD OF THE FRONT...BREEZY/GUSTY SOUTHERLY WINDS CONTINUE
OVER MUCH OF THE CWA WITH TEMPS STILL VERY MILD.
AS THE UPPER LOW KICKS OUT INTO THE PLAINS LATER THIS MORNING...A
REGENERATION OF SHOWERS AND STORMS IS EXPECTED OVER THE WESTERN
DAKOTAS. THE LATEST RUN OF THE HRRR AND THE 00Z NSSL WRF SHOW
WESTERN SOUTH DAKOTA SEEING THE BULK OF THE ACTIVITY THROUGH THE
MORNING HOURS...WITH CENTRAL SOUTH DAKOTA HOLDING OFF UNTIL THE
AFTERNOON. WILL HAVE TO WAIT FOR THE UPPER LOW TO GET CLOSER TO
THE AREA IT APPEARS FOR RAINFALL CHANCES TO INCREASE. 00Z NSSL WRF
INDICATES SHOWER AND THUNDERSTORM ACTIVITY DEVELOPING BETWEEN THE
MISSOURI AND JAMES RIVERS BY AROUND 21Z. ALL MODELS INDICATING
THAT THIS SYSTEM WILL WEAKEN AS IT CONTINUES MOVING EAST...WITH
BAND OF RAINFALL DISSIPATING AND BECOMING MORE WIDELY SCATTERED AS
IT MOVES EAST OF THE JAMES VALLEY. HAVE CONSTRUCTED WX/POP GRIDS
TO REFLECT THIS THINKING AND KEPT HIGHEST POPS OVER THE WESTERN
CWA THROUGHOUT THE DAY.
WITH THE SLOWER MOVEMENT OF THE UPPER LOW AND SURFACE
FRONT...HAVE INCREASED HIGHS A COUPLE DEGREES OVER THE EASTERN CWA
WHERE SOUTHERLY WINDS WILL REMAIN AND 850MB TEMPS STAY THE
WARMEST. SPEAKING OF WINDS...EXPECT ANOTHER WINDY DAY FOR THE
EASTERN COUNTIES...BUT LIKELY STAYING BELOW ADVISORY LEVELS.
TUESDAY AND TUESDAY NIGHT WILL BE QUIET AS A WEAK SURFACE RIDGE
SLIDES EAST OVER THE AREA. LOOK FOR MILD TEMPS AND DRY CONDITIONS.
WINDS BEGIN TO INCREASE AGAIN BY WEDNESDAY AS ANOTHER LOW PRESSURE
SYSTEM DEVELOPS TO THE WEST OF THE REGION.
.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY
MAIN FCST CHALLENGE FACING THE EXTENDED PORTION OF FORECAST
REVOLVES AROUND PCPN CHANCES HEADING INTO THE WEEKEND...AND TEMPS
FOR NEXT WEEKEND.
MODELS CONT TO ADVERTISE A LONG WAVE TROF MOVING INTO THE INTERMTN
STATES TO BEGIN THE EXTENDED FOR THE WEDNESDAY NIGHT PERIOD. GOOD
MID LEVEL WAA AHEAD OF THIS TROF AS INDICATED BY 700HPA THETA-E
FORCING. HOWEVER...BOTH GFS AND LATEST EC SUGGEST SFC WINDS WILL
BE MORE SERLY WHICH TYPICALLY ISN`T A GOOD WARMING WIND FOR THE
CWA. THIS WILL PROBABLY HELP TO TEMPER HIGHS SOMEWHAT FROM WHAT
THEY COULD BE GIVEN A SOUTH OR EVEN SW WIND. THE EC IS A BIT
SLOWER THAN GFS ON ARRIVAL OF PCPN...WAITING UNTIL CLOSER TO 12Z
FRIDAY FOR ONSET. THAT SAID...SINCE STILL LOOKING AT 5 DAYS
OUT...AM CONTENT TO LEAVE ALLBLEND GRID ALONE AND REFINE AS
SHORTER TERM MODELS BEGIN TO COVER THIS TIME FRAME.
WITH COLD FROPA DURING THE DAY FRIDAY WITH PLENTY OF EXPECTED
CLOUD COVER...COOLISH TEMPS FRIDAY/SATURDAY SEEM
REALISTIC...ESPECIALLY WITH BOTH GFS AND EC SHOWING 850HPA TEMPS
IN THE +4C TO +6C RANGE. WAA RETURNS IN EARNEST FOR SUNDAY..SO
FORECAST HIGHS ABOUT A CATEGORY WARMER THAN SATURDAY ALSO SEEMS
PLAUSIBLE.
&&
.AVIATION...
18Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
SCATTERED RAIN SHOWERS WILL MOVE OVER THE FAR WESTERN CWA DURING
THE LATE AFTERNOON AND EVENING HOURS. AT THIS TIME...IT APPEARS
THAT CIGS AND VSBYS WILL REMAIN VFR WITH THE RAIN AS IT AFFECT
KMBG AND KPIR. LITTLE IN THE WAY OF RAINFALL IS EXPECTED AT KABR
AND KATY WHERE DRIER AIR WILL BE IN PLACE. SKIES WILL CLEAR BY
TUESDAY MORNING. SOUTHERLY WINDS OF 15 TO 30 MPH THIS AFTERNOON
WILL DIMINISH AND BECOME LIGHT AFTER SUNSET.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...SERR
SHORT TERM...TMT
LONG TERM...HINTZ
AVIATION...PARKIN
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1136 AM PDT Mon Sep 23 2013
.SYNOPSIS...
Cooler air behind a cold front which moved through last night will
drop temperatures below normal for most of the week with a threat
of showers through Wednesday. The weather will then dry out with a
gradual warming trend through next weekend.
&&
.DISCUSSION...
Remainder of today...Swift west-southwest upper level jet has
shifted into eastern Washington late this morning and extended
from the NW Oregon coast toward Mullan Pass. For the most part
this has delivered a drying trend to much of the region...with
most of the residual showers persisting either near the Cascade
Crest over over the northern half of the Idaho Panhandle. The
question for later today is will the showers become more numerous
through the day. If the short range model solutions are on
track...we should see a rapid growth in showers especially over NE
Washington and the northern half of the ID Panhandle as these areas
are situated under the favorable left front quadrant of the upper
level jet. Meanwhile any diurnal heating should result in a quick
destabilization of the atmosphere. The question is will the
instability be deep enough to produce showers. Over the Columbia Basin
the answer is probably no as there is still a lot of downslope
westerly flow to overcome off the Cascades. Meanwhile The same
west- southwest flow low/mid atmosphere flow should bring good
orographical ascent to the NE corner of Washington and the
Panhandle. The only fly in the ointment is the HRRR model is not
depicting much threat of showers anywhere this afternoon until
after 22z...and even then its quite limited. Usually its wise to
follow its trends...however its underplaying the current batch of
showers currently situated over eastern Shoshone County...so we
will ignore for now. fx
&&
.AVIATION...
18Z TAFS: VFR conditions expected though much of the period aside
from some brief MVFR conditions through 20-21z or so around KGEG-
KCOE due to a small area of stratocumulus which recently formed
over the area. This cloud deck should rise into 3500-5000 ft range
as daytime heating continues into the afternoon. These sites also
will see a small risk of showers aft 21z due in part to the
daytime heating. We do not expect to see anything more than very
light rain. For tonight all locations will experience vfr
conditions until a weak warm front moves into SE WA and NC ID aft
10z or so. Cigs will lower steadily in advance of the front...and
MVFR heights are a good possibility. The question is how soon will
they lower to these levels. For now we went with after 15z...but
that could prove a little too late if front moves in quicker than
expected. fx
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 62 45 59 42 59 43 / 20 20 50 30 20 10
Coeur d`Alene 61 45 58 42 57 42 / 20 20 60 30 30 10
Pullman 63 45 57 40 58 40 / 10 40 70 40 30 10
Lewiston 70 52 60 48 64 46 / 10 30 70 60 40 30
Colville 64 44 62 41 64 40 / 30 20 30 40 20 10
Sandpoint 57 43 55 37 55 38 / 40 40 50 50 30 20
Kellogg 57 44 55 40 54 40 / 40 60 70 60 30 30
Moses Lake 69 47 66 44 68 44 / 10 10 30 20 10 0
Wenatchee 66 48 65 47 66 47 / 10 10 20 30 30 0
Omak 66 42 65 42 66 42 / 10 10 20 20 10 0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
258 PM CDT MON SEP 23 2013
.SYNOPSIS...
ISSUED AT 258 PM CDT MON SEP 23 2013
THE INFLUENCE OF HIGH PRESSURE WILL KEEP THE UPPER MISSISSIPPI
RIVER VALLEY DRY THIS WEEK...AND ALLOW TEMPERATURES TO GRADUALLY
WARM FROM NORMAL TO SLIGHTLY ABOVE NORMAL READINGS BY THURSDAY
AND FRIDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 258 PM CDT MON SEP 23 2013
AFTERNOON WATER VAPOR IMAGERY OVERLAID WITH RAP 500 MB ANALYSIS
SHOWS RATHER DEEP NEGATIVELY TITLED UPPER LEVEL SHORTWAVE TROUGH
EJECTING OUT INTO THE CENTRAL PLAINS. AT THE SURFACE...A 997 MB
LOW RESIDES IN NW KANSAS WITH A NICE CURL SEEN IN VISIBLE
SATELLITE IMAGERY. IT IS THIS SYSTEM THAT WILL BE LIFTING TOWARD
THE UPPER MIDWEST TONIGHT INTO TUESDAY.
23.12Z GUIDANCE REMAINS SUPPORTIVE OF A DRY FORECAST WITH THIS
SYSTEM AS A COMBINATION OF WEAKENING DYNAMICS AND LIMITED
MOISTURE TRANSPORT LEAVES A LOT TO BE DESIRED. ACROSS THE
BOARD...500-300 MB PV ADVECTION...300-310K ISENTROPIC LIFT...AND
850 MB MOISTURE TRANSPORT ALL WEAKEN OR BECOME NON-EXISTENT
BETWEEN 06Z AND 15Z TUESDAY. OUTSIDE OF MID TO HIGH LEVEL CLOUDS
SPREADING IN FROM THE WEST INITIALLY WITH THE WARM AIR ADVECTION
WING...LITTLE TO NO IMPACT EXPECTED WITH THIS SYSTEM. PLAN ON
ANOTHER PLEASANT AUTUMN DAY WITH MOSTLY TO PARTLY SUNNY SKIES AND
HIGHS A COUPLE DEGREES ON EITHER SIDE OF 70F.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 258 PM CDT MON SEP 23 2013
DRY/QUIET WEATHER TUESDAY NIGHT THROUGH FRIDAY AS RIDGE OF HIGH
PRESSURE INFLUENCES THE SENSIBLE WEATHER ACROSS THE UPPER MIDWEST.
BY WEDNESDAY...THE AFOREMENTIONED SYSTEM DECAYS AND SLOWS ACROSS
THE MID ATLANTIC MEANWHILE A WESTERN CONUS SHORTWAVE TROUGH DIGS
DOWN NEAR THE FOUR CORNERS REGION. THIS PUTS THE CENTRAL PLAINS
UNDER DRY...WARMING SOUTHWESTERLY FLOW. 925 MB TEMPERATURES ARE
EXPECTED TO CLIMB EACH DAY...FROM NEAR SEASONAL LEVELS WEDNESDAY
TO SLIGHTLY ABOVE NORMAL BY THURSDAY...AND TO NEAR 80 IN SOME
SPOTS BY FRIDAY.
WEDNESDAY MORNING CONDITIONS LOOK SOMEWHAT FAVORABLE FOR RIVER
VALLEY FOG AS HIGH PRESSURE CENTERS ITSELF ACROSS CENTRAL
WISCONSIN. FORECAST SOUNDINGS SHOW A VERY DEEP LAYER OF LIGHT
WINDS LESS THAN 10 KTS UP TO 600 MB...THOUGH THERE IS A LACK OF
LOW LEVEL SATURATION...BUT COULD BE ENOUGH TO PATCHY RIVER VALLEY
FOG. THE OTHER COMPETING FACTOR IS THE POSSIBILITY OF A
NORTH/SOUTH ORIENTED MID LEVEL STRATUS DECK SETTING UP ALONG OR
JUST WEST OF THE MS RIVER. THIS IS SEEN IN THE GFS/NAM RH FIELDS
AT 850 AND 700 MB. FOR NOW...HAVE ADDED PATCHY VALLEY FOG TO MS
AND WISCONSIN RIVER VALLEYS.
FOCUS TURNS TO LATE FRIDAY NIGHT INTO THE UPCOMING WEEKEND SYSTEM
AS THE WESTERN SHORTWAVE TROUGH MOVES INTO THE NORTHERN AND
CENTRAL PLAINS. AS PIECES OF ENERGY ROUND THE SHORTWAVE TROUGH...A
COUPLE OF SURFACE LOWS ARE EXPECTED TO FORM...AND EVENTUALLY DRAG
A COLD FRONT THROUGH THE AREA. MOISTURE AHEAD OF THE FRONT
INCREASES...AND BROAD BUT PERSISTENT ISENTROPIC LIFT ON THE
305-315K SURFACES IS SEEN. THERE IS WEAK INSTABILITY ASSOCIATED
WITH THE SYSTEM...BUT MOST OF THE PRECIPITATION LOOKS TO BE POST-
FRONTAL. THE POSITIVE TILTED NATURE OF THE SHORTWAVE TROUGH MAKES
TIMING DETAILS A BIT UNCERTAIN AND DIFFICULT...AS THERE REMAINS
SOME DISAGREEMENT BETWEEN THE 23.12Z GUIDANCE. HOWEVER...ALL
GUIDANCE DID TREND MUCH SLOWER THAN PREVIOUS RUNS...THOUGH WITH
VARYING DEGREES. THE GEM/ECMWF SUGGESTS MOST OF SATURDAY WOULD
REMAIN DRY...HOLDING PRECIPITATION BACK UNTIL SATURDAY NIGHT OR
SUNDAY. THE GFS IS A TOUCH FASTER BUT STILL SLOWER THAN ITS
PREVIOUS RUN. AS A RESULT...HAVE PUSHED BACK PRECIPITATION
TIMING...ESPECIALLY EAST OF THE MISSISSIPPI RIVER. STILL PLENTY OF
TIME TO IRON OUT THE SPECIFICS. IN THE WAKE OF THIS SYSTEM...A
RETURN TO SEASONABLY COOL AND DRY WEATHER THANKS TO CANADIAN HIGH
PRESSURE BUILDING INTO THE UPPER MIDWEST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1201 PM CDT MON SEP 23 2013
HIGH PRESSURE OVER THE GREAT LAKES WILL KEEP VFR WEATHER ACROSS THE
OHIO VALLEY THIS AFTERNOON AND EVENING WITH A LIGHT EAST TO
NORTHEAST BREEZE. DO EXPECT SCATTERED CLOUDS ABOUT 4-5 KFT WILL
DEVELOP OR MOVE IN AS MODEST MOISTURE RETURN BEGINS. BWG STANDS THE
BEST SHOT AT HAVING CEILINGS NEAR MVFR BY EARLY IN THE DAY ON
WEDNESDAY. MAY HAVE TO INCLUDE SOME VCSH AT SOME POINT ACROSS SOUTH
CENTRAL KENTUCKY FOR WEDNESDAY, BUT AM NOT CONFIDENT ENOUGH IN
COVERAGE AT THIS TIME TO MENTION.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SYNOPSIS.....ZT
SHORT TERM...ZT
LONG TERM....ZT
AVIATION.....DAS