Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 09/30/15
AREA FORECAST DISCUSSION
NWS PUEBLO CO
335 PM MDT MON SEP 28 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 335 PM MDT MON SEP 28 2015
...COOLER WEATHER MOVING INTO THE REGION...
CURRENTLY...
COOL FRONT WAS MOVING SLOWLY SOUTHWARD ACROSS THE PLAINS EARLY THIS
AFTERNOON. WELL DEFINED BOUNDARY WAS NOTED ON KPUX AT 3 PM RUNNING
NEARLY E-W FROM JUST N OF KPUB TO JUST N OF EADS. NORTH OF THIS
BOUNDARY WINDS WERE GENERALLY FROM THE NORTH WHILE SOUTH OF THIS
BOUNDARY EASTERLY WINDS WERE NOTED. A LINE OF WEAK CUMULUS WERE
NOTED WITH THE BOUNDARY ACROSS THE PLAINS.
A WEAK SHORT WAVE WAS NOTED ACROSS W WY/NW CO THIS AFTERNOON AND IT
IS THIS WAVE THAT WILL BRING THE FRONT DOWN THE PLAINS LATER TODAY
AND INTO THIS EVENING.
REST OF TODAY INTO TONIGHT...
WE WILL LIKELY SEE SOME SHOWERS DEVELOP OVER THE PLAINS THIS
AFTERNOON INTO THIS EVENING. MODELS VARY ON INTENSITY AND
LOCATION...BUT THERES A GOOD CHANCE WE WILL SEE SOME ACTIVITY...WITH
THE BEST CHANCES BEING GENERALLY N OF HIGHWAY 50. HRRR IS THE MOST
AGGRESSIVE OF THE GUIDANCE WITH A CLUSTER OF WEAK STORMS FORMING UP IN
EL PASO COUNTY AND THEN DROPPING EAST-SOUTHEAST ACROSS THE PLAINS.
HRRR HAS BEEN HANGING ONTO THIS SOLUTION FOR SEVERAL RUNS...BUT
BELIEVE IT MAY BE OVERDONE AS COMPARED TO OTHER GUIDANCE.
AS FOR CLOUDS LATER TONIGHT...EXPECT WE WILL SEE A BROKEN DECK
DEVELOP BUT BELIEVE ANY CIG WILL MAINLY BE A MID LVL DECK AS PER
SOUNDINGS. CANT RULE OUT SOME LOWER CLOUDS UP IN N EL PASO COUNTY
AND MAYBE OVER THE FAR E PLAINS.
WE WILL LIKELY SEE SOME GUSTY NE WINDS DEVELOP SOON OVER THE EL
PASO/PUEBLO COUNTY REGION AND LAST INTO EARLY EVENING AS THE FRONT
SURGES SOUTH.
TOMORROW...
MOS PRODUCTS SHOW RATHER HIGH POPS TOMORROW ACROSS THE
REGION...ESPECIALLY ALONG THE MTNS/PLAINS INTERFACE. GIVEN THE
UPSLOPE FLOW AND FORCING...PRECIP WILL OCCUR BUT I AM A BIT HESITANT
ON GOING AS HIGH AS MOS GUIDANCE. FOR NOW PAINTED THE GREATER I-25
CORRIDOR REGION IN SCATTERED POPS WITH MORE ISOLATED POPS ACROSS THE
REST OF THE REGION. AS THE AFTERNOON PROGRESSES...BETTER CHANCE OF
PRECIP WILL BE ALONG THE RATON MESA REGION
AS FOR TIMING...SHOWERS WILL BE POSSIBLE AS EARLY AS LATE MORNING
ACROSS THE PIKES PEAK REGION...AND THE AREA OF PRECIP WILL INCREASE
AS IT MOVES SOUTH-SOUTHEAST DOWN THE S MTN RANGE.
THE BIG NEWS TOMORROW WILL BE THE SEASONABLE TEMPERATURES THAT WILL
FINALLY RETURN TO THE AREA...AS HIGHS WILL ONLY BE IN THE 60S ACROSS
N EL PASO COUNTY AND 70S ACROSS THE REST OF THE PLAINS. VALLEYS WILL
REMAIN WARMER THAN NORMAL AS COOLER AIR WILL NOT GET INTO THE LARGER
VALLEYS. WILL LIKELY SEE QUITE A BIT OF CLOUDINESS OVER THE REGION
TOMORROW. /HODANISH
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 335 PM MDT MON SEP 28 2015
.TUESDAY NIGHT...CONVECTION ON THE PLAINS WILL MOVE INTO NEW
MEXICO. MODELS TRY TO DEVELOP SOME PRECIPITATION OVER WESTERN
KANSAS OVERNIGHT WITH A WEAK DISTURBANCE PASSING TO OUR NORTH.
BELIEVE PRECIPITATION WILL STAY TO THE NORTHEAST OF THE CWA AND
HAVE ONLY SILENT POPS AFTER MIDNIGHT.
.WEDNESDAY...UPSLOPE FLOW WILL PERSIST OVER THE PLAINS WITH DEW
POINTS FORECAST TO BE IN THE LOWER 50S. SPC DAY 3 OUTLOOK HAS A
MARGINAL RISK FOR PORTIONS OF THE SOUTHEAST PLAINS. MODELS HAVE
CAPES AROUND 1000 J/KG. WITH FORECAST 500MB WINDS AROUND 30
KNOTS...THERE WILL BE ENOUGH SHEAR FOR STRONGER STORMS. SHORTWAVE
APPEARS TO BE LACKING WHICH CAN HINDER THE DEVELOPMENT OF
CONVECTION...GIVEN THE WEAKER AUTUMN SOLAR HEATING. HAVE SOME
ISOLATED POPS IN THE GRIDS FOR THE POTENTIAL FOR A FEW STRONGER
STORMS TO DEVELOP.
.THURSDAY...UPPER RIDGE MOVES OVER THE REGION FOR A DRY AND WARM
DAY.
.FRIDAY THROUGH MONDAY...MODELS AND ENSEMBLES HAVE A SHORTWAVE
MOVING OVER THE REGION FRIDAY INTO SATURDAY. WITH LOW LEVEL
UPSLOPE ON THE PLAINS...THERE IS THE POTENTIAL FOR STRATIFORM
PRECIPITATION TO DEVELOP OVER THE PLAINS ON FRIDAY INTO FRIDAY
NIGHT. BEST FORCING WILL MOSTLY BE OVER THE NORTHERN HALF OF THE
STATE. KEPT POPS ONLY IN THE SCATTERED CATEGORY FOR NOW AS
AGREEMENT AMONG THE MODELS ON THE SPECIFIC DETAILS ARE LOW. THE
MODEL DIFFERENCE BECOME MORE PRONOUNCED STARTING SATURDAY. EC AND
CANADIAN HAVE THE LEADING SHORTWAVE MOVE EAST OF THE REGION BY
SATURDAY. A MUCH STRONGER DISTURBANCE MOVES INTO THE PACIFIC
NORTHWEST SATURDAY...THEN PROGRESSES INTO THE GREAT BASIN BY
MONDAY. THIS IS A WARMER SOLUTION WITH MOISTURE FROM HURRICANE
MARTY MOVING INTO THE REGION. THE GFS LACKS THE SECOND SHORTWAVE
AND IT HAS AN UPPER LOW STALLING OVER COLORADO. THIS WOULD PROVIDE
A MUCH COOLER AND WETTER SOLUTION. WPC SOLUTION SEEMS TO BE THE
BLEND OF THE TWO AND PREDICTABILITY IS BELOW AVERAGE. CR EXTENDED
GRIDS ARE A DECENT COMPROMISE OF THE TWO SOLUTIONS AND ONLY
TWEAKED THE GRIDS FOR CONSISTENCY. WITH A TROUGH NEARBY...THIS
WEEKEND COULD BE COOLER WITH MORE AUTUMN LIKE TEMPERATURES.
--PGW--
--PGW--
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 335 PM MDT MON SEP 28 2015
OVERALL...VFR CONDITIONS EXPECTED NEXT 24H AT ALL 3 TAF
SITES...KPUB...KALS AND KCOS.
A COOL FRONT WAS MOVING DOWN THE PLAINS THIS AFTERNOON AND GUSTY
NORTH-NORTHEAST WINDS WILL BE LIKELY LATER THIS AFTERNOON AND EARLY
EVENING OVER KCOS AND POSSIBLY KPUB. A FEW SHOWERS MAY BE
POSSIBLE...ESPECIALLY OVER KCOS THIS AFTERNOON/EARLY EVENING. CIGS
WILL LIKELY DEVELOP BUT SHOULD BE PREDOMINANTLY MID LVL.
TOMORROW...SHOWERS WITH A FEW ISOLD TSRA ARE LIKELY AT KCOS AND
POSSIBLY AT KPUB. SHOWERS WILL FORM RELATIVELY EARLY (LATE MORNING?)
AND MOVE SOUTH-SOUTHEAST DOWN THE I-25 CORRIDOR REGION. BEST CHANCE
OF PRECIP WILL BE ALONG THE MTNS/PLAINS INTERFACE.
KALS WILL REMAIN DRY WITH LIGHT WINDS.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...HODANISH
LONG TERM...PGW
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1134 PM MDT SUN SEP 27 2015
.UPDATE...
ISSUED AT 956 PM MDT SUN SEP 27 2015
SOME THIN HIGH CLOUD ACROSS THE FORECAST AREA...BUT MUCH OF THE
REGION IS ABLE TO OBSERVE THE SUPERMOON ECLIPSE. THE HRRR MAY BE
OVERDOING THE THREAT OF PRECIPITATION OVER THE UINTA MOUNTAINS
TONIGHT. DO NOT SEE ANY EVIDENCE THAT SHOWERS ARE FORMING ON SALT
LAKE`S RADAR OUR OURS...SO TEMPERED THE POP GRIDS A BIT IN THE
EVENING UPDATE. APPEARED THAT SHOWERS DID FORM ALONG THE NRN
BORDER OF DAGGETT COUNTY BEFORE SUNSET...BUT THESE HAVE SINCE
DISSIPATED.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 326 PM MDT SUN SEP 27 2015
THE UPPER RIDGE THAT HAS BEEN OVER THE REGION WILL CONTINUE TO
FLATTEN AND SHIFT TO THE SOUTHWEST DURING THE NEXT COUPLE OF DAYS.
AS A RESULT THE FLOW WILL BECOME MORE WESTERLY AND CARRY A COUPLE
OF WEAK WAVES FROM WEST TO EAST...MAINLY NORTH OF OUR FORECAST
AREA. THE TAIL END OF ONE WAVE WILL BRUSH OUR NORTHERN EDGE
TONIGHT. AS A RESULT WE HAVE SEEN A BETTER CUMULUS DEVELOPMENT
OVER THE UINTA...FLATTOPS AND PARK RANGES THIS AFTERNOON. A FEW
SHOWERS AND THUNDERSTORMS MAY ALSO DEVELOP LATE THIS AFTERNOON AND
EARLY THIS EVENING. OF MOST INTEREST FOR TONIGHT`S FORECAST WILL
BE THE AMOUNT OF EXPECTED CLOUD COVER FOR THE LUNAR ECLIPSE THIS
EVENING. IT APPEARS SOME HIGH CLOUDS MAY FILTER THE VIEW FOR MUCH
OF THE AREA...BUT THESE CLOUDS WILL GENERALLY BE THIN. THE
EXCEPTION WILL BE FROM AROUND THE TAVAPUTS PLATEAU/FLATTOPS AND
NORTH...WHERE CLOUDS MAY BE A LITTLE THICKER. BUT EVEN THERE THE
MOON SHOULD BE SOMEWHAT VISIBLE. OVERNIGHT TEMPS ARE EXPECTED TO
BE A LITTLE WARMER DUE TO THE BETTER CLOUDS.
ENERGY WILL CONTINUE TO ROUND THE TOP OF THE RIDGE AND BRUSH THE
NORTHERN EDGE OF OUR FORECAST AREA THROUGH MON NIGHT. THEREFORE A
FEW SHOWERS AND LATE DAY THUNDERSTORMS WILL CONTINUE TO BE
POSSIBLE ACROSS THE NORTH...FAVORING THE HIGHER TERRAIN. LITTLE
CHANGE IS EXPECTED IN AFTERNOON HIGH TEMPERATURES ON MONDAY...
WITH LOWS INCREASING JUST A LITTLE MONDAY NIGHT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 326 PM MDT SUN SEP 27 2015
A FEW SHOWERS AND THUNDERSTORMS WILL CONTINUE OVER THE NORTH ON
TUESDAY...POSSIBLY LINGERING OVERNIGHT AS ANOTHER WAVE BRUSHES
THE FORECAST AREA. ON WED THE RIDGE WILL REBOUND ALONG THE UT/CO
BORDER...PUMPED UP BY THE NEXT LOW PRESSURE TROUGH APPROACHING THE
WEST COAST.
WHILE THE MID TERM MODELS ARE IN FAIR AGREEMENT ON THE BIG
PICTURE...THERE CONTINUES TO BE SOME RATHER SIGNIFICANT TIMING
DIFFERENCES IN WHEN THIS LOW PRESSURE SYSTEM AND ITS ASSOCIATED
COLD FRONT WILL REACH THE FORECAST AREA...AND IN HOW QUICK THE
TROUGH EXITS TO THE EAST. IN ANY CASE...THE RIDGE WILL DOMINATE
WED AND THU AHEAD OF THE TROUGH. SOUTHWEST WINDS WILL PICK UP ON
THU AS THE GRADIENT TIGHTENS AHEAD OF THE SYSTEM AS IT MOVES INTO
THE GREAT BASIN.
THE ECMWF IS FASTER BY AROUND 12 HOURS...WITH THE COLD
FRONT JUST ABOUT TO OUR NORTHWEST CORNER AT 00Z FRI. THE EC ALSO
SHOWS THE LOW CENTER QUICKLY BRUSHING OUR NORTHERN EDGE EARLY
FRIDAY AND EAST OF THE FORECAST AREA BY THE AFTERNOON. A SHORTWAVE
RIDGE THEN FOLLOWS FOR SUN. AS MENTIONED ABOVE...THE GFS IS
AROUND 12 HOURS SLOWER...WITH THE FRONT REACHING THE NORTHWEST
CORNER AT AROUND 12Z FRI. IN THIS SOLUTION THE LOW CENTER WILL
MOVE OVER NE UT/NW CO/SW WY FRI EVENING...AND LINGER OVER
NORTHWEST CO THROUGH EARLY SAT. ENERGY THEN SPLITS OFF THE MAIN
LOW AND RETROGRADES...LEAVING GENERAL TROUGHINESS OVER WY TO THE
GREAT BASIN THROUGH SUN. FOR NOW HAVE KEPT THE BEST CHANCE OF
SHOWERS/THUNDERSTORMS ON FRI AFTERNOON...WITH A DOWNTURN AFTER
THAT. EXPECT THAT THE FORECAST WILL CONTINUE TO BE ADJUSTED AS
THIS SYSTEM NEARS AND MODEL SOLUTIONS EVOLVE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1130 PM MDT SUN SEP 27 2015
ISOLATED SHOWERS AND THUNDERSTORMS WILL DEVELOP OVER THE MOUNTAINS
AFTER 19Z MONDAY AND LINGER THROUGH 02Z MONDAY EVENING. STORMS
WILL PRODUCE GUSTY OUTFLOW WINDS TO 35 MPH AND ONLY LIGHT RAINFALL
AMOUNTS. OTHERWISE...VFR CONDITIONS WILL BE HOLDING IN PLACE
THROUGH MONDAY NIGHT WITH SFC WINDS GENERALLY UNDER 15 KTS.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATE...PF
SHORT TERM...EH
LONG TERM...EH
AVIATION...JDC
AREA FORECAST DISCUSSION
NWS TAUNTON MA
730 PM EDT TUE SEP 29 2015
.SYNOPSIS...
A COLD FRONT SLOWLY APPROACHES FROM THE WEST LATE TONIGHT...THEN
BEGINS TO CROSS SOUTHERN NEW ENGLAND WEDNESDAY MORNING...STALLING
OFFSHORE LATE WEDNESDAY. WAVES OF LOW PRESSURE WILL MOVE ALONG
THIS FRONT THROUGH LATE WEEK. WITH HIGH PRESSURE OVER QUEBEC...
POTENTIAL REMAINS FOR STRONG ONSHORE WINDS...COASTAL FLOODING AND
HEAVY RAIN WITH POSSIBLE INLAND FLOODING. THESE THREATS MAY
PERSIST INTO THIS WEEKEND AS THE STALLED FRONT MAY PUSH BACK INTO
SOUTHERN NEW ENGLAND.
&&
.NEAR TERM /UNTIL 4 AM WEDNESDAY MORNING/...
730 PM UPDATE...
ONLY MINOR TWEAKS TO THE FORECAST THIS EVENING TO REFLECT THE
LATEST OBSERVED TRENDS. LATEST RUNS OF THE HRRR SEEM TO HAVE
GENERAL IDEA ON TWO SEPARATE AREAS OF RAINFALL THIS EVENING. THE
EASTERN AREA IS VERY THIN...AND MOVING RIGHT ALONG. NOT EXPECTING
MUCH RAINFALL FROM IT THIS EVENING.
STILL WATCHING THE LARGER AREA OF HEAVIER RAINFALL TO OUR WEST.
SLOWED ITS ARRIVAL JUST A BIT. STILL EXPECTING IT TO OVERSPREAD
MOST OF SOUTHERN NEW ENGLAND OVERNIGHT.
PREVIOUS DISCUSSION...
THROUGH 4 AM...CLOUDS WILL FILL BACK IN AHEAD OF THE COLD FRONT AS
IT SLOWLY APPROACHES SOUTHERN NEW ENGLAND TONIGHT. IN ADDITION...
THE APPROACHING FRONT WILL BRING MORE WIDESPREAD SHOWERS TO THE
REGION. EXPECT MOST OF THIS TIME PERIOD TO STILL BE SCATTERED
SHOWERS THOUGH MORE WIDESPREAD RAINFALL MAY BEGIN AN HOUR OR TWO
BEFORE 4 AM. THERE IS A LOW PROBABILITY OF ISOLATED THUNDER IN SOME
OF THESE SHOWERS. FINALLY...FOG WILL DEVELOP AGAIN TONIGHT...
RESULTING IN REDUCED VISIBILITIES. EXPECT THE FOG TO BE FAIRLY
WIDESPREAD GIVEN THE UPPER 60S TO AROUND 70 DEGREE DEWPOINTS.
BECAUSE OF THE LOW CLOUDS...FOG...RAIN...AND HIGH DEWPOINTS...EXPECT
WARM OVERNIGHT TEMPERATURES...GENERALLY IN THE UPPER 60S TO AROUND
70.
&&
.SHORT TERM /4 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
FROM EARLY WEDNESDAY THROUGH WEDNESDAY EVENING...
SYNOPSIS...COLD FRONT STRETCHING FROM QUEBEC BACK TO THE SOUTHWEST
WILL MOVE ACROSS SOUTHERN NEW ENGLAND DURING THIS TIMEFRAME STALLING
SOMEWHERE BETWEEN CAPE COD CANAL AND JUST OFFSHORE THE CAPE AND
ISLANDS. THERE IS SOME UNCERTAINTY AS TO JUST WHERE THE FRONT SLOWS
AND THEN STALLS DUE TO THE STRENGTH OF THE WESTERN ATLANTIC RIDGE.
OTHERWISE...MODELS ARE IN FAIRLY GOOD AGREEMENT ON THE OVERALL
PATTERN.
RAINFALL...SHOWERS BECOME MORE WIDESPREAD AS THE COLD FRONT MOVES
ACROSS SOUTHERN NEW ENGLAND. MAIN CONCERN FOR THE DAY IS HEAVY RAIN
GIVEN PRECIPITABLE WATER VALUES 2 TO 3 STD ABOVE NORMAL. GIVEN HOW
DRY WE HAVE BEEN IN THE PAST FEW WEEKS TO MONTHS...NOT EXPECTING ANY
MAINSTEM RIVER FLOODING WITH THIS EVENT. THE CONCERN WE DO HAVE
WITH THE HEAVY RAIN IS FOR URBAN AND POOR DRAINAGE FLOODING. THERE
IS A LOW PROBABILITY OF FLOODING ON SOME OF THE FLASHIER SMALLER
RIVERS AND URBAN WATERSHEDS. OVERALL...EXPECTING A WIDESPREAD 2 TO 4
INCHES OF RAIN WITH LOCALLY HEAVIER AMOUNTS.
THUNDER...THERE IS A POTENTIAL FOR A FEW ISOLATED THUNDERSTORMS.
WHILE THERE IS PLENTY OF LIFT AND CONVERGENCE ASSOCIATED WITH THE
FRONT...THERE IS NOT VERY MUCH INSTABILITY TO WORK WITH.
THEREFORE...NOT EXPECTING ANY SEVERE WEATHER.
TIMING...EXPECT TWO MAIN SLUGS OF RAIN WITH THIS SYSTEM. THE FIRST
ONE WILL BE EARLY WEDNESDAY MORNING /PRIOR TO THE MORNING COMMUTE/
WITH THE HIGHEST AMOUNTS ACROSS WESTERN MASSACHUSETTS AND
CONNECTICUT. THE SECOND ONE WILL BE LATER WEDNESDAY MORNING INTO
EARLY WEDNESDAY AFTERNOON WITH THE HIGHEST AMOUNTS FOCUSED NORTH OF
THE MASS PIKE. THEREFORE WE HAVE KEPT THE FLOOD WATCH AS IS WITH
THE FOCUS GENERALLY NORTH AND WEST OF INTERSTATE 95.
WIND...SHOULD NOT BE MUCH OF AN ISSUE DURING THIS TIME FRAME. WINDS
WILL INCREASE AND BECOME GUSTY AS THE FRONT MOVES THROUGH. DESPITE A
LOW LEVEL JET INCREASING TO 40 TO 45 KTS IN THE LATE AFTERNOON...
EXPECT A LOW LEVEL INVERSION WILL HOLD WIND GUSTS TO JUST 20 TO 25
MPH THROUGH THE AFTERNOON. THE EXCEPTION WILL BE IN ANY HEAVIER
SHOWERS OR THUNDERSTORMS...WHERE THESE HIGHER GUSTS MAY BE ABLE TO
MIX TO THE SURFACE.
COASTAL FLOODING...SEE TIDES/COASTAL FLOODING SECTION BELOW.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
HIGHLIGHTS...
* OCCASIONAL RAIN AND PERSISTENT GUSTY NORTHEAST WINDS THROUGH
THIS WEEKEND
* MINOR COASTAL FLOODING POSSIBLE DURING THE THU AFTERNOON AND FRI
AFTERNOON TIDE CYCLES
* POTENTIAL FOR RENEWED HEAVY RAIN AND FLOODING IMPACTS FRIDAY...
POSSIBLY LINGERING THROUGH THIS WEEKEND
OVERVIEW...TREMENDOUS UNCERTAINTY REMAINS REGARDING THE DETAILS
OF THIS PORTION OF THE FORECAST...ESPECIALLY FROM THIS WEEKEND
INTO EARLY NEXT WEEK. THE FORECAST WILL ULTIMATELY DEPEND ON THE
PROGRESS AND DEVELOPMENT OF TROPICAL STORM JOAQUIN.
VERY COMPLEX FLOW PATTERN HIGHER UP IN THE ATMOSPHERE...WITH LOTS
OF MOVING PARTS. WILL HAVE TO SEE HOW EVERYTHING LINES UP OVER
THE NEXT FEW DAYS. RIGHT NOW...ONLY HAVE MODERATE CONFIDENCE TO
SPEAK IN GENERALITIES. HAVE LOW CONFIDENCE IN THE DETAILS SUCH AS
TIMING AND TRACK.
HIGH AMPLITUDE FLOW PATTERN DEVELOPS IN RESPONSE TO A STRONG
PERSISTENT BLOCKING RIDGE OVER THE WESTERN NORTH ATLANTIC. AS THE
NORTHERN BRANCH OF THE JETSTREAM AMPLIFIES A TROUGH OVER THE GREAT
LAKES...A CLOSED LOW SHOULD EVOLVE OVER THE SOUTHEAST USA. THIS
WOULD ULTIMATELY MEAN TWO CAMPS FOR POSSIBLE TRACKS OF JOAQUIN.
ONE...WOULD BE WELL SOUTH OF OUR REGION...WHICH COULD HAPPEN IF
JOAQUIN REALLY SLOWS DOWN. THE MORE LIKELY POSSIBILITY...AND IN
LINE WITH NHC FORECAST...IS FOR JOAQUIN TO GRADUALLY TURN NORTH
ALONG THE EASTERN SEABOARD. THE BIG QUESTION THEN IS...HOW CLOSE
TO THE COAST WILL IT TRACK.
RESIDENTS AND THOSE WITH INTERESTS IN SOUTHERN NEW ENGLAND SHOULD
MONITOR LATER FORECASTS OF JOAQUIN.
DETAILS...
WEDNESDAY NIGHT INTO SUNDAY...GOOD MULTI-MODEL AGREEMENT ON A
COLD FRONT MOVING TO THE VICINITY OF CAPE COD AND THE ISLANDS BY
WEDNESDAY EVENING...THEN MOVING SLIGHTLY FARTHER OFFSHORE
WEDNESDAY NIGHT. THIS FRONT WILL BE THE FOCUS FOR HEAVY RAINFALL
ACROSS SOUTHERN NEW ENGLAND AS VERY STRONG CONVERGENCE AND LOW
LEVEL FRONTOGENESIS ACT ON ANOMALOUS PRECIPITABLE WATER VALUES
OVER 2 INCHES. THESE VALUES ARE +3 STANDARD DEVIATIONS ABOVE
NORMAL. AS THIS FRONT SETTLES FARTHER SOUTH WEDNESDAY NIGHT INTO
THURSDAY...THE HEAVIEST RAINFALL WILL SHIFT SOUTH WITH IT.
HOWEVER...WITH PERSISTENT +2 STANDARD DEVIATION PRECIPITABLE WATER
VALUES AND GOOD NORTHEAST INFLOW...EXPECTING OCCASIONAL RAIN WILL
CONTINUE THROUGH THURSDAY...ESPECIALLY ACROSS SOUTHEAST NEW
ENGLAND...WITH A LESSER THREAT FARTHER NORTHWEST.
AS MENTIONED ABOVE...THE UNCERTAINTY WITH JOAQUIN IS LARGE. THIS
WILL BE A MAJOR FACTOR IN OUR WEATHER THIS WEEKEND INTO EARLY NEXT
WEEK. SHOULD JOAQUIN GET CLOSE TO OUR REGION...WE COULD SEE TOTAL
RAINFALL SUFFICIENT ENOUGH TO WIPE OUT OUR CURRENT ANNUAL
DEFICITS. HOWEVER...THERE IS LOW CONFIDENCE ON WHERE THE AXIS OF
HEAVY RAINFALL GETS ESTABLISHED. WITH LITTLE CONFIDENCE IN THE
TRACK AND TIMING OF JOAQUIN...HAVE A PROLONGED PERIOD WITH A RISK
FOR RAINFALL...ALTHOUGH NOT EXPECTING IT TO BE RAINING THE ENTIRE
TIME. THESE DETAILS SHOULD COME INTO BETTER FOCUS OVER THE NEXT
FEW DAYS.
GUSTY NORTHEAST WINDS WILL DEVELOP ALONG THE COAST STARTING
WEDNESDAY EVENING AND CONTINUING THROUGH AT LEAST FRIDAY...AND
POSSIBLY INTO THIS WEEKEND AS STRONG PRESSURE GRADIENT DEVELOPS
BETWEEN ANOMALOUS SURFACE HIGH WELL TO THE NORTH AND LOW PRESSURE
TO THE SOUTH. POTENTIAL FOR GUSTS TO 40 MPH ACROSS EAST COASTAL
MA...AND PARTICULARLY THE NORTH SHORE...LATE WEDNESDAY NIGHT
THROUGH THURSDAY NIGHT. ANOTHER PULSE OF GUSTY WINDS POSSIBLE
THIS WEEKEND. THESE GUSTY NORTHEAST WINDS COMBINED WITH HIGH
ASTRONOMICAL TIDES WILL INCREASE THREAT OF MINOR COASTAL FLOODING
DURING THE THURSDAY AND FRIDAY AFTERNOON HIGH TIDE CYCLES.
MONDAY AND TUESDAY...
LOW CONFIDENCE FORECAST AS MODELS STRUGGLING WITH HOW QUICKLY THE
DOWNSTREAM BLOCKING RIDGE BREAKS DOWN AND SUBSEQUENT DRYING.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
TONIGHT INTO WEDNESDAY...HIGH CONFIDENCE ON TRENDS...LOW
CONFIDENCE ON TIMING.
CONDITIONS WILL DETERIORATE TONIGHT AS SHOWERS BEGIN TO DEVELOP
AHEAD OF AN APPROACHING COLD FRONT. EXPECT MVFR/IFR CONDITIONS
THIS EVENING AS LOW CLOUDS AND FOG DEVELOP. HEAVY RAIN WILL MOVE
INTO WESTERN SITES CLOSER TO DAYBREAK AND MOVE EASTWARD
THROUGH THE DAY. CONDITIONS COULD DROP AS LOW AS IFR/LIFR. CANNOT
RULE OUT ISOLD TSRA AHEAD OF THIS FRONT.
GUSTY SOUTHERLY WINDS WILL DEVELOP OUT AHEAD OF THE FRONT CLOSE
TO 20-30 KTS...ESP ACROSS THE CAPE AND ISLANDS THEN SWITCH TO THE
NORTH BEHIND THE FRONT. LLWS IS LIKELY LATE WEDNESDAY TOWARD THE
CAPE AND ISLANDS AND EVEN AT KBOS.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF TRENDS...LOW CONFIDENCE IN
TIMING.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF TRENDS...LOW CONFIDENCE IN
TIMING.
OUTLOOK /WEDNESDAY NIGHT THROUGH SUNDAY/...MODERATE CONFIDENCE.
EXPECT PERIODS OF IFR CIGS/VSBYS IN PERIODS OF RAIN THROUGH MOST OF
THIS PERIOD. NE WINDS GUSTING UP TO 25-35 KT...HIGHEST ACROSS E
COASTAL MA.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
HIGH CONFIDENCE. SMALL CRAFT ADVISORIES CONTINUE THROUGH
WEDNESDAY. SEAS BUILD THROUGH THE PERIOD ON PERSISTENT
SOUTHEASTERLY WINDS. INCREASED WAVEWATCH GUIDANCE BY 20 PERCENT
BASED ON ITS TENDENCY TO UNDERFORECAST. THIS HAS RESULTED IN 8-10
FOOT SEAS ON THE OUTER WATERS BY WEDNESDAY EVENING. A COLD FRONT
WILL APPROACH THE COASTAL WATERS LATE WEDNESDAY...RESULTING IN
WINDS GUSTING TO 25 TO 30 KTS. THIS COLD FRONT WILL ALSO BRING
WIDESPREAD HEAVY RAIN WHICH WILL LIMIT VSBYS ON WEDNESDAY.
OUTLOOK /WEDNESDAY NIGHT THROUGH SUNDAY/...MODERATE CONFIDENCE.
EXPECT PERSISTENT NE WINDS DURING THIS TIMEFRAME. GUSTS UP TO 35-40
KT ARE LIKELY STARTING WED NIGHT THROUGH AT LEAST THU NIGHT. GALE
WATCHES REMAIN POSTED TO GIVE THE NEXT SHIFT A CHANCE TO LOOK
THINGS OVER. SEAS WILL ALSO BUILD...HIGHEST ACROSS THE EASTERN
OUTER WATERS...WHICH MAY REACH UP TO 15 FT. WINDS MAY TEMPORARILY
DIMINISH A BIT FRI BEFORE INCREASING AGAIN SAT. EXPECT PERIODS OF
HEAVY RAIN AND REDUCED VSBYS.
&&
.TIDES/COASTAL FLOODING...
WEDNESDAY ALONG SOUTH COAST...
COMBINATION OF HIGH ASTRONOMICAL TIDE AND SOUTHERLY FETCH WARRANTS
COASTAL FLOOD ADVISORY FOR PORTIONS OF THE RI AND MA SOUTH
COAST. ANTICIPATING A SURGE NEAR 1.0 FEET...JUST A FEW FEET ABOVE
THE ESTOFS GUIDANCE FOR THE WEDNESDAY MID TO LATE MORNING HIGH
TIDE IN THAT AREA. THAT IS THE ONLY HIGH TIDE CYCLE OF CONCERN FOR
THE SOUTH COAST.
WEDNESDAY NIGHT THROUGH FRIDAY ALONG EAST COAST...
BEHIND THE COLD FRONT THE WIND INCREASES FROM THE NE AND WE BEGIN
TO SEE POSITIVE SURGES ALONG THE MA EAST COAST...STARTING WED
NIGHT. A SURGE OF .5 TO 1.0 FEET MAY BE ENOUGH FOR AREAS OF MINOR
COASTAL FLOODING ALONG THE E COAST LATE WED NIGHT/VERY EARLY THU
AM. AS THE NE FLOW PERSISTS...WE SEE THE POTENTIAL FOR THE SURGE
TO INCREASE INTO THE 1.0 TO 1.5 FOOT RANGE WITH ADDITIONAL MINOR
COASTAL FLOODING AROUND THE TIME OF HIGH TIDE POSSIBLE. FOR NOW
PLAN TO HOLD OFF ON ANY HEADLINES FOR THE E COAST. SOME BEACH
EROSION IS LIKELY DUE TO THE HIGH WATER LEVELS AND MODERATE WAVE
ACTION THAT MAY APPROACH JUST 15 FEET OFFSHORE.
WEEKEND OUTLOOK...
THE WEEKEND OUTLOOK IS HIGHLY UNCERTAIN AS IT COULD DEPEND IN
PART ON THE EVOLUTION OF JOAQUIN. PRELIMINARY INDICATIONS SUGGEST
A PERSISTENT NE FLOW THAT COULD KEEP THE SURGE RUNNING 1 TO 1.5
FEET WHILE THE ASTRONOMICAL HIGH TIDES GRADUALLY BECOME LESS.
WEDNESDAY SEPTEMBER 30 PROVIDENCE HIGH TIDE AT 1021 AM
DATE / BOSTON HIGHEST TIDE / TIME
WEDNESDAY SEPTEMBER 30 / 12.2 FEET / 1:25 PM
THURSDAY OCTOBER 1 / 12.0 FEET / 2:17 PM
FRIDAY OCTOBER 2 / 11.5 FEET / 3:30 PM
SATURDAY OCTOBER 3 / 11.0 FEET / 4:06 PM
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...FLOOD WATCH FROM 2 AM EDT WEDNESDAY THROUGH THURSDAY MORNING
FOR CTZ002>004.
MA...FLOOD WATCH FROM 2 AM EDT WEDNESDAY THROUGH THURSDAY MORNING
FOR MAZ002>012-014-026.
COASTAL FLOOD ADVISORY FROM 8 AM TO NOON EDT WEDNESDAY FOR
MAZ020.
RI...COASTAL FLOOD ADVISORY FROM 8 AM TO NOON EDT WEDNESDAY FOR
RIZ002-004>007.
MARINE...GALE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY EVENING
FOR ANZ231>235-237-254>256.
SMALL CRAFT ADVISORY FROM 5 AM TO 8 PM EDT WEDNESDAY FOR
ANZ231>234.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT WEDNESDAY FOR ANZ235-237-
250-254>256.
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY EVENING FOR
ANZ250-251.
SMALL CRAFT ADVISORY FROM 8 AM TO 8 PM EDT WEDNESDAY FOR
ANZ251.
&&
$$
SYNOPSIS...BELK/RLG
NEAR TERM...BELK/RLG
SHORT TERM...RLG
LONG TERM...BELK
AVIATION...BELK/RLG
MARINE...BELK/RLG
TIDES/COASTAL FLOODING...THOMPSON
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1231 PM EDT MON SEP 28 2015
.SYNOPSIS...
HIGH PRESSURE EXTENDED FROM THE NORTHEASTERN STATES OUT OVER THE
ATLANTIC EARLY THIS MORNING AND WEAK LOW PRESSURE WAS LOCATED OFF
THE SOUTHEAST COAST. THE HIGH WILL CONTINUE TO MOVE FARTHER OUT TO
SEA AND THE LOW SHOULD DRIFT NORTHWARD THROUGH TUESDAY NIGHT. A
COLD FRONT IS FORECAST TO APPROACH FROM THE NORTHWEST AND IT
SHOULD PASS THROUGH OUR REGION ON WEDNESDAY. THE BOUNDARY IS
EXPECTED TO STALL OFF THE COAST FOR THURSDAY AND FRIDAY AS AREAS
OF LOW PRESSURE MOVE NORTHWARD ALONG IT. ONE OF THE LOWS IS
ANTICIPATED TO STRENGTHEN AS IT REACHES EASTERN CANADA OVER THE
WEEKEND, PULLING THE FRONT FARTHER OUT TO SEA AND ALLOWING HIGH
PRESSURE TO BEGIN BUILDING INTO OUR REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SURFACE HIGH PRESSURE RIDGE REMAINS ENTRENCHED ALONG THE
APPALACHIANS. LOW LEVEL MOISTURE DUE TO THE CONTINUED ONSHORE
FLOW AND A WEAKER PRESSURE GRADIENT HAS ALLOWED FOG TO DEVELOP
THIS MORNING, ESPECIALLY CLOSER TO THE COAST. EXPECT THE FOG TO
DISSIPATE BY LATE MORNING, WITH CONSIDERABLE CLOUDINESS FOR THE
REMAINDER OF THE DAY. THERE IS GREATER MOISTURE IN THE COLUMN
COMPARED TO YESTERDAY, BUT THERE IS NOT MUCH IN THE WAY OF LIFT,
SO EXPECTING A DRY DAY. THE ONLY EXCEPTION WILL BE ALONG THE COAST
WHERE THE NAM AND HRRR INDICATE SOME LIGHT RAIN SHOWERS MOVING
ONSHORE. CURRENT RADAR AND SATELLITE TRENDS SUPPORT THIS, SO HAVE
INSERTED A SLIGHT CHANCE OF RAIN SHOWERS INTO THE FORECAST ALONG
THE COAST. ALSO MADE SOME ADJUSTMENTS TO REDUCE SKY COVER AND
INCREASE MAX TEMPS A COUPLE DEGREES SOUTHEAST OF I-95.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
THE DRY AIR CONTINUES TO BE REPLACED BY EVEN MORE MOIST AIR
OVERNIGHT TONIGHT AS THE HIGH PULLS FARTHER AWAY FROM THE AREA.
WITH ADDITIONAL VORTICITY IMPULSES WITHIN THE SOUTHWEST FLOW
ALOFT, RAIN CHANCES CONTINUE TO INCREASE OVERNIGHT. ADDITIONALLY,
THERE COULD BE SOME FOG DEVELOP ONCE AGAIN, ESPECIALLY FOR HIGHER
ELEVATIONS ACROSS NORTHEAST PENNSYLVANIA AND NORTHWEST NEW JERSEY.
WE`VE INCLUDED FOG ONCE AGAIN IN THE GRIDS ACROSS THOSE AREAS
WHERE VISIBILITIES MAY BE LOWER. OVERNIGHT LOWS ARE EXPECTED TO BE
SEVERAL DEGREES ABOVE NORMAL, AS CLOUDS SHOULD PREVENT ANY
RADIATIONAL COOLING.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
THE HIGH OFF THE COAST WILL CONTINUE TO LOSE ITS INFLUENCE OVER
OUR REGION ON TUESDAY. WARM HUMID AIR IS ANTICIPATED TO SETTLE
INTO OUR REGION WITH MAXIMUM TEMPERATURES EXPECTED TO BE MAINLY IN
THE UPPER 70S AND LOWER 80S. THE POTENTIAL FOR RAIN SHOWERS WILL
BE ON THE INCREASE THROUGH THE DAY, ESPECIALLY IN OUR COUNTIES IN
EASTERN PENNSYLVANIA AS A COLD FRONT BEGINS TO APPROACH FROM THE
NORTHWEST.
THE MODEL GUIDANCE HAS BEEN TRENDING TOWARD A LESS PROGRESSIVE
SOLUTION WITH THE COLD FRONT. IT NOW APPEARS AS THOUGH IT WILL
PASS THROUGH OUR FORECAST AREA ON WEDNESDAY BEFORE STALLING OFF
THE COAST FOR THURSDAY AND FRIDAY.
PRECIPITABLE WATER VALUES ARE FORECAST TO REACH AND EXCEED 2
INCHES IN MOST OF OUR FORECAST AREA AHEAD OF THE COLD FRONT. AS A
RESULT, WE WILL CONTINUE TO MENTION THE POTENTIAL FOR HEAVY
RAINFALL. ALSO, WE HAVE INCLUDED A CHANCE OF THUNDERSTORMS AS THE
LIFT WITH AND AHEAD OF THE FRONT SEEMS FAIRLY ROBUST. GENERAL
RAINFALL AMOUNTS OF AN INCH OR TWO SEEM POSSIBLE FOR MUCH OF OUR
REGION. BEING THAT ANTECEDENT CONDITIONS HAVE BEEN QUITE DRY, OUR
THINKING IS THAT WE WILL SEE SOME LOCALIZED FLOODING IN AREAS OF
POOR DRAINAGE BUT THE POSSIBILITY OF WIDESPREAD FLOODING IS LOW.
CLOUDS AND A CHANCE OF LIGHT RAIN SHOULD LINGER DURING THE LATE
WEEK PERIOD WITH THE FRONT STALLED OFF THE COAST. THE TIMING AND
STRENGTH OF LOW PRESSURE WAVES MOVING ALONG THE BOUNDARY REMAINS
QUITE UNCERTAIN AT THIS TIME, SO THE DETAILS OF THE FORECAST
REMAIN LOW CONFIDENCE AT THIS POINT.
WE WILL GO WITH THE IDEA OF A STRENGTHENING LOW FINALLY BEGINNING
TO PULL THE FRONT FARTHER OFF THE COAST OVER THE WEEKEND. IT MAY
ALLOW HIGH PRESSURE AND SOME CLEARING TO BEGIN WORKING INTO OUR
REGION FROM THE WEST AT THAT TIME.
DAYTIME TEMPERATURES SHOULD FALL BELOW NORMAL FOR THE LATE WEEK
PERIOD INTO THE WEEKEND IN THE WAKE OF THE COLD FRONT.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
CEILINGS HAVE LOWERED TO IFR AT DAYBREAK. FOG HAS ALSO DEVELOPED,
WITH THE LOWEST CEILINGS NEAR THE COAST, WHERE ACY HAS BEEN DOWN
TO 1/4SM ATTMS. THE FOG SHOULD DIMINISH AROUND 15Z. HOWEVER, THE
LOW CLOUDS ARE EXPECTED TO REMAIN ACROSS THE SITES THROUGH MID
MORNING, THEN BEGIN LIFTING TO MVFR, THEN VFR BY THE AFTERNOON.
AFTER A PERIOD OF VFR FOR THE AFTERNOON INTO THE EARLY EVENING,
CIGS ARE EXPECTED TO LOWER BACK TO MVFR DURING THE EVENING HOURS,
AND EVENTUALLY BACK TO IFR/LIFR OVERNIGHT. IN ADDITION, FOG MAY BE
MORE EXTENSIVE TONIGHT AND TUESDAY MORNING.
NORTHEASTERLY WINDS EARLY IN THE DAY ARE EXPECTED TO BECOME MORE
EASTERLY, THEN SOUTHEASTERLY LATER IN THE DAY AND CONTINUE INTO
THE OVERNIGHT HOURS. WIND SPEEDS ARE EXPECTED TO BE 5-10 KNOTS
THROUGH THE PERIOD.
OUTLOOK...
TUESDAY...IFR AND MVFR CONDITIONS IN THE MORNING GRADUALLY
IMPROVING TO MAINLY VFR FOR THE AFTERNOON. A CHANCE OF SHOWERS.
TUESDAY NIGHT AND WEDNESDAY...RAIN DEVELOPING AND BECOMING HEAVY
AT TIMES ALONG WITH A CHANCE OF THUNDERSTORMS. MVFR AND IFR
CONDITIONS ARE LIKELY.
WEDNESDAY NIGHT...MAINLY VFR WITH A CHANCE OF RAIN.
THURSDAY...MAINLY VFR. A CHANCE OF RAIN, MOSTLY TO THE SOUTH AND
SOUTHEAST OF KPHL.
THURSDAY NIGHT...MAINLY VFR.
FRIDAY...MAINLY VFR WITH A CHANCE OF RAIN.
&&
.MARINE...
AS THE FLOW RELAXES ACROSS THE AREA, WINDS HAVE DROPPED BELOW 25
KNOTS. HOWEVER, SEAS REMAIN ELEVATED ACROSS THE WATERS. THEREFORE
WE WILL KEEP THE SMALL CRAFT ADVISORY, BUT HAVE CONVERTED IT TO
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS.
OUTLOOK...
TUESDAY AND TUESDAY NIGHT...A SMALL CRAFT ADVISORY REMAINS IN
EFFECT FOR OUR OCEAN WATERS WITH WAVE HEIGHTS EXPECTED TO RANGE
FROM 4 TO 6 FEET.
WEDNESDAY THROUGH FRIDAY...SMALL CRAFT ADVISORY CONDITIONS WILL
LIKELY CONTINUE ON OUR OCEAN WATERS AND ON DELAWARE BAY DUE TO AN
INCREASING NORTHEAST WIND. WAVE HEIGHTS ON OUR OCEAN WATERS ARE
FORECAST TO BUILD TO 6 TO 12 FEET. GALE FORCE GUSTS ARE POSSIBLE
ON OUR OCEAN WATERS FROM WEDNESDAY NIGHT INTO FRIDAY.
&&
.TIDES/COASTAL FLOODING...
TIDES WILL CONTINUE TO RUN HIGH TODAY INTO TONIGHT AND APPROACH
THE MINOR FLOOD LEVEL. HOWEVER, WE DO NOT EXPECT THE LEVELS TO
REACH CRITERIA REQUIRED TO ISSUE A FLOOD ADVISORY.
A STRONG NORTHEASTERLY SURFACE FLOW IS FORECAST TO REDEVELOP
DURING THE SECOND HALF OF THE WORK WEEK. AS A RESULT, WE MAY SEE
ANOTHER ROUND OF MINOR TIDAL FLOODING AT THAT TIME. ALSO, BEACH
EROSION IS POSSIBLE.
&&
.RIP CURRENTS...
THE COMBINATION OF HIGH WAVES, MODERATE PERIOD SWELL, AND A
STEADY EASTERLY FLOW WILL CONTINUE TO CREATE A HIGH RISK FOR THE
DEVELOPMENT OF DANGEROUS RIP CURRENTS THROUGH THIS EVENING.
AFTER TODAY, THERE MAY BE A WEAK ENOUGH FLOW ON TUESDAY AND
WEDNESDAY TO HAVE THE DANGEROUS RIP CURRENT RISK LESS THAN HIGH.
THE SURF ZONE FORECAST ENDS WITH THE MORNING FORECAST ON
WEDNESDAY THE 30TH.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR NJZ014-
024>026.
DE...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR DEZ004.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT
WEDNESDAY FOR ANZ450>455.
&&
$$
SYNOPSIS...IOVINO
NEAR TERM...FRANCK/ROBERTSON
SHORT TERM...ROBERTSON
LONG TERM...IOVINO
AVIATION...FRANCK/IOVINO/ROBERTSON
MARINE...FRANCK/IOVINO/ROBERTSON
TIDES/COASTAL FLOODING...
RIP CURRENTS...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
928 AM EDT MON SEP 28 2015
.SYNOPSIS...
HIGH PRESSURE EXTENDED FROM THE NORTHEASTERN STATES OUT OVER THE
ATLANTIC EARLY THIS MORNING AND WEAK LOW PRESSURE WAS LOCATED OFF
THE SOUTHEAST COAST. THE HIGH WILL CONTINUE TO MOVE FARTHER OUT TO
SEA AND THE LOW SHOULD DRIFT NORTHWARD THROUGH TUESDAY NIGHT. A
COLD FRONT IS FORECAST TO APPROACH FROM THE NORTHWEST AND IT
SHOULD PASS THROUGH OUR REGION ON WEDNESDAY. THE BOUNDARY IS
EXPECTED TO STALL OFF THE COAST FOR THURSDAY AND FRIDAY AS AREAS
OF LOW PRESSURE MOVE NORTHWARD ALONG IT. ONE OF THE LOWS IS
ANTICIPATED TO STRENGTHEN AS IT REACHES EASTERN CANADA OVER THE
WEEKEND, PULLING THE FRONT FARTHER OUT TO SEA AND ALLOWING HIGH
PRESSURE TO BEGIN BUILDING INTO OUR REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SURFACE HIGH PRESSURE RIDGE REMAINS ENTRENCHED ALONG THE
APPALACHIANS. LOW LEVEL MOISTURE DUE TO THE CONTINUED ONSHORE
FLOW AND A WEAKER PRESSURE GRADIENT HAS ALLOWED FOG TO DEVELOP
THIS MORNING, ESPECIALLY CLOSER TO THE COAST. EXPECT THE FOG TO
DISSIPATE BY LATE MORNING, WITH CONSIDERABLE CLOUDINESS FOR THE
REMAINDER OF THE DAY. THERE IS GREATER MOISTURE IN THE COLUMN
COMPARED TO YESTERDAY, BUT THERE IS NOT MUCH IN THE WAY OF LIFT,
SO EXPECTING A DRY DAY. THE ONLY EXCEPTION WILL BE ALONG THE
COAST WHERE THE NAM AND HRRR INDICATE SOME LIGHT RAIN SHOWERS
MOVING ONSHORE. CURRENT RADAR AND SATELLITE TRENDS SUPPORT THIS,
SO HAVE INSERTED A SLIGHT CHANCE OF RAIN SHOWERS INTO THE
FORECAST ALONG THE COAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
THE DRY AIR CONTINUES TO BE REPLACED BY EVEN MORE MOIST AIR
OVERNIGHT TONIGHT AS THE HIGH PULLS FARTHER AWAY FROM THE AREA.
WITH ADDITIONAL VORTICITY IMPULSES WITHIN THE SOUTHWEST FLOW
ALOFT, RAIN CHANCES CONTINUE TO INCREASE OVERNIGHT. ADDITIONALLY,
THERE COULD BE SOME FOG DEVELOP ONCE AGAIN, ESPECIALLY FOR HIGHER
ELEVATIONS ACROSS NORTHEAST PENNSYLVANIA AND NORTHWEST NEW JERSEY.
WE`VE INCLUDED FOG ONCE AGAIN IN THE GRIDS ACROSS THOSE AREAS
WHERE VISIBILITIES MAY BE LOWER. OVERNIGHT LOWS ARE EXPECTED TO BE
SEVERAL DEGREES ABOVE NORMAL, AS CLOUDS SHOULD PREVENT ANY
RADIATIONAL COOLING.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
THE HIGH OFF THE COAST WILL CONTINUE TO LOSE ITS INFLUENCE OVER
OUR REGION ON TUESDAY. WARM HUMID AIR IS ANTICIPATED TO SETTLE
INTO OUR REGION WITH MAXIMUM TEMPERATURES EXPECTED TO BE MAINLY IN
THE UPPER 70S AND LOWER 80S. THE POTENTIAL FOR RAIN SHOWERS WILL
BE ON THE INCREASE THROUGH THE DAY, ESPECIALLY IN OUR COUNTIES IN
EASTERN PENNSYLVANIA AS A COLD FRONT BEGINS TO APPROACH FROM THE
NORTHWEST.
THE MODEL GUIDANCE HAS BEEN TRENDING TOWARD A LESS PROGRESSIVE
SOLUTION WITH THE COLD FRONT. IT NOW APPEARS AS THOUGH IT WILL
PASS THROUGH OUR FORECAST AREA ON WEDNESDAY BEFORE STALLING OFF
THE COAST FOR THURSDAY AND FRIDAY.
PRECIPITABLE WATER VALUES ARE FORECAST TO REACH AND EXCEED 2
INCHES IN MOST OF OUR FORECAST AREA AHEAD OF THE COLD FRONT. AS A
RESULT, WE WILL CONTINUE TO MENTION THE POTENTIAL FOR HEAVY
RAINFALL. ALSO, WE HAVE INCLUDED A CHANCE OF THUNDERSTORMS AS THE
LIFT WITH AND AHEAD OF THE FRONT SEEMS FAIRLY ROBUST. GENERAL
RAINFALL AMOUNTS OF AN INCH OR TWO SEEM POSSIBLE FOR MUCH OF OUR
REGION. BEING THAT ANTECEDENT CONDITIONS HAVE BEEN QUITE DRY, OUR
THINKING IS THAT WE WILL SEE SOME LOCALIZED FLOODING IN AREAS OF
POOR DRAINAGE BUT THE POSSIBILITY OF WIDESPREAD FLOODING IS LOW.
CLOUDS AND A CHANCE OF LIGHT RAIN SHOULD LINGER DURING THE LATE
WEEK PERIOD WITH THE FRONT STALLED OFF THE COAST. THE TIMING AND
STRENGTH OF LOW PRESSURE WAVES MOVING ALONG THE BOUNDARY REMAINS
QUITE UNCERTAIN AT THIS TIME, SO THE DETAILS OF THE FORECAST
REMAIN LOW CONFIDENCE AT THIS POINT.
WE WILL GO WITH THE IDEA OF A STRENGTHENING LOW FINALLY BEGINNING
TO PULL THE FRONT FARTHER OFF THE COAST OVER THE WEEKEND. IT MAY
ALLOW HIGH PRESSURE AND SOME CLEARING TO BEGIN WORKING INTO OUR
REGION FROM THE WEST AT THAT TIME.
DAYTIME TEMPERATURES SHOULD FALL BELOW NORMAL FOR THE LATE WEEK
PERIOD INTO THE WEEKEND IN THE WAKE OF THE COLD FRONT.
&&
.AVIATION /13Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
CEILINGS HAVE LOWERED TO IFR AT DAYBREAK. FOG HAS ALSO DEVELOPED,
WITH THE LOWEST CEILINGS NEAR THE COAST, WHERE ACY HAS BEEN DOWN
TO 1/4SM ATTMS. THE FOG SHOULD DIMINISH AROUND 15Z. HOWEVER, THE
LOW CLOUDS ARE EXPECTED TO REMAIN ACROSS THE SITES THROUGH MID
MORNING, THEN BEGIN LIFTING TO MVFR, THEN VFR BY THE AFTERNOON.
AFTER A PERIOD OF VFR FOR THE AFTERNOON INTO THE EARLY EVENING,
CIGS ARE EXPECTED TO LOWER BACK TO MVFR DURING THE EVENING HOURS,
AND EVENTUALLY BACK TO IFR/LIFR OVERNIGHT. IN ADDITION, FOG MAY BE
MORE EXTENSIVE TONIGHT AND TUESDAY MORNING.
NORTHEASTERLY WINDS EARLY IN THE DAY ARE EXPECTED TO BECOME MORE
EASTERLY, THEN SOUTHEASTERLY LATER IN THE DAY AND CONTINUE INTO
THE OVERNIGHT HOURS. WIND SPEEDS ARE EXPECTED TO BE 5-10 KNOTS
THROUGH THE PERIOD.
OUTLOOK...
TUESDAY...IFR AND MVFR CONDITIONS IN THE MORNING GRADUALLY
IMPROVING TO MAINLY VFR FOR THE AFTERNOON. A CHANCE OF SHOWERS.
TUESDAY NIGHT AND WEDNESDAY...RAIN DEVELOPING AND BECOMING HEAVY
AT TIMES ALONG WITH A CHANCE OF THUNDERSTORMS. MVFR AND IFR
CONDITIONS ARE LIKELY.
WEDNESDAY NIGHT...MAINLY VFR WITH A CHANCE OF RAIN.
THURSDAY...MAINLY VFR. A CHANCE OF RAIN, MOSTLY TO THE SOUTH AND
SOUTHEAST OF KPHL.
THURSDAY NIGHT...MAINLY VFR.
FRIDAY...MAINLY VFR WITH A CHANCE OF RAIN.
&&
.MARINE...
AS THE FLOW RELAXES ACROSS THE AREA, WINDS HAVE DROPPED BELOW 25
KNOTS. HOWEVER, SEAS REMAIN ELEVATED ACROSS THE WATERS. THEREFORE
WE WILL KEEP THE SMALL CRAFT ADVISORY, BUT HAVE CONVERTED IT TO
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS.
OUTLOOK...
TUESDAY AND TUESDAY NIGHT...A SMALL CRAFT ADVISORY REMAINS IN
EFFECT FOR OUR OCEAN WATERS WITH WAVE HEIGHTS EXPECTED TO RANGE
FROM 4 TO 6 FEET.
WEDNESDAY THROUGH FRIDAY...SMALL CRAFT ADVISORY CONDITIONS WILL
LIKELY CONTINUE ON OUR OCEAN WATERS AND ON DELAWARE BAY DUE TO AN
INCREASING NORTHEAST WIND. WAVE HEIGHTS ON OUR OCEAN WATERS ARE
FORECAST TO BUILD TO 6 TO 12 FEET. GALE FORCE GUSTS ARE POSSIBLE
ON OUR OCEAN WATERS FROM WEDNESDAY NIGHT INTO FRIDAY.
&&
.TIDES/COASTAL FLOODING...
TIDES WILL CONTINUE TO RUN HIGH TODAY INTO TONIGHT AND APPROACH
THE MINOR FLOOD LEVEL. HOWEVER, WE DO NOT EXPECT THE LEVELS TO
REACH CRITERIA REQUIRED TO ISSUE A FLOOD ADVISORY.
A STRONG NORTHEASTERLY SURFACE FLOW IS FORECAST TO REDEVELOP
DURING THE SECOND HALF OF THE WORK WEEK. AS A RESULT, WE MAY SEE
ANOTHER ROUND OF MINOR TIDAL FLOODING AT THAT TIME. ALSO, BEACH
EROSION IS POSSIBLE.
&&
.RIP CURRENTS...
THE COMBINATION OF HIGH WAVES, MODERATE PERIOD SWELL, AND A
STEADY EASTERLY FLOW WILL CONTINUE TO CREATE A HIGH RISK FOR THE
DEVELOPMENT OF DANGEROUS RIP CURRENTS THROUGH THIS EVENING.
AFTER TODAY, THERE MAY BE A WEAK ENOUGH FLOW ON TUESDAY AND
WEDNESDAY TO HAVE THE DANGEROUS RIP CURRENT RISK LESS THAN HIGH.
THE SURF ZONE FORECAST ENDS WITH THE MORNING FORECAST ON
WEDNESDAY THE 30TH.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR NJZ014-
024>026.
DE...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR DEZ004.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT
WEDNESDAY FOR ANZ450>455.
&&
$$
SYNOPSIS...IOVINO
NEAR TERM...FRANCK
SHORT TERM...ROBERTSON
LONG TERM...IOVINO
AVIATION...FRANCK/IOVINO/ROBERTSON
MARINE...IOVINO/ROBERTSON
TIDES/COASTAL FLOODING...
RIP CURRENTS...
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
521 AM EDT MON SEP 28 2015
...A CLOSE CALL FOR HEAVY RAINFALL ALONG THE FLORIDA WEST COAST
LATER TODAY THROUGH TUESDAY MORNING...
...FLOOD WATCH IN EFFECT FOR COASTAL COUNTIES FROM SARASOTA
NORTHWARD TO LEVY...
.SYNOPSIS...
08Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A VERY STAGNANT UPPER
LEVEL SYNOPTIC PATTERN IN PLACE ACROSS THE CONUS EARLY THIS MORNING.
THE MAIN FEATURES OF NOTE HAVE NOT MOVED MUCH SINCE EARLY SUNDAY
MORNING. THE MAIN NORTHERN STREAM FLOW REMAINS CONFINED OVER
SOUTHERN CANADA...AS IT RIDES UP AND OVER AN UPPER RIDGE IN PLACE
ACROSS THE DESERT SOUTHWEST. THE UPPER LEVEL PATTERN FURTHER TO
THE EAST AND SOUTH OVER OUR REGION IS QUITE COMPLEX. A DEEP TROUGH
ANCHORED BY A LARGE CLOSED UPPER LOW FEATURE OVER THE TEXAS COAST
REMAINS STALLED TO OUR WEST...WHILE THESE HEIGHT FALLS HAVE
PROMOTED A STRENGTHENING UPPER RIDGE OFF THE FLORIDA EAST COAST.
THE HEIGHT GRADIENT BETWEEN THESE FEATURES IS ALLOWING A
DEEP...AND MOIST...SOUTH TO SOUTHWEST FLOW FROM THE CENTRAL GULF
OF MEXICO TO THE WESTERN FLORIDA PENINSULA. WV IMAGERY SHOWS A
DEEP MOISTURE PLUME OUT OF THE NW CARIBBEAN MOVING OVER OUR
HEADS...AND THE 28/12Z KTBW SOUNDING PROFILE AGAIN SAMPLED A
COLUMN WITH AN OVER 2" PW VALUE. THE MEASURED VALUE OF 2.12" IS
MORE THAN THE 90TH PERCENTILE OF VALUES FOR THE END OF SEPTEMBER.
PERIODIC WEAK IMPULSES EMBEDDED WITHIN THE SOUTHERLY FLOW ALOFT
HAVE BEEN PROVIDING THE FOCUS FOR CLUSTERS OF SHWRS/STORMS WORKING
ALONG/JUST OFF THE SUNCOAST EARLY THIS MORNING. ALTHOUGH THE
FORCING WITH THESE FEATURES IS WEAK...THE DEEP MOISTURE IN THE
COLUMN AND GENERAL WEAK DIFFLUENCE ALOFT IS COMBINING TO PRODUCE
EFFICIENT CONVECTION AHEAD OF EACH IMPULSE.
AT THE SURFACE...A WEAK AREA OF LOW PRESSURE HAS EMERGED OFF THE
YUCATAN PENINSULA AND IS SLOWLY MOVING NORTHWARD THROUGH THE CENTRAL
GULF OF MEXICO. OUR LOW LEVEL FLOW IS GENERALLY A LIGHT INFLOW FROM
THE EAST/ESE RIGHT NOW...BUT WILL BE VEERING TOWARD THE SOUTH TODAY
AS THE LOW CONTINUES TO TRACK NORTHWARD TOWARD THE NORTH-CENTRAL
GULF COAST. THE TRACK OF THIS LOW CONTINUES TO BE QUITE PROBLEMATIC
FOR OUR FORECAST. FOR SEVERAL DAYS THE NWP GUIDANCE HAS SUGGESTED
THIS SYSTEM WOULD PLACE THE FL WEST COAST ON THE VERY EDGE OF THE
BEST SYNOPTIC FORCING/HEAVY RAIN POTENTIAL. WE WERE HOPING THAT AS
THE EVENT DREW NEAR...A TREND EAST OR WEST WOULD OCCUR...MAKING THE
FORECAST MORE DEFINITIVE TOWARD WET OR DRY. HOWEVER...THIS DEVIATION
TOWARD THE LEFT OR RIGHT HAS NOT OCCURRED IN THE SIMULATIONS...AND
THE GUIDANCE CONSENSUS HOLDS ONTO THE "MIDDLE OF THE ROAD" TRACK AND
ORGANIZATION STRUCTURE. UNFORTUNATELY...THIS RESULTS IN THE FORECAST
TODAY AGAIN BEING OF LOWER CONFIDENCE THAN USUAL...DUE TO THE
IMPLICATIONS THAT ONLY SMALL DEVIATIONS IN TRACK OR ORGANIZATION OF
THE LOW MAY HAVE FOR OUR LOCAL WEATHER (HEAVIER RAIN POTENTIAL ALONG
THE COAST VS. STAYING JUST OFFSHORE).
&&
.SHORT TERM (TODAY THROUGH TUESDAY)...
AS MENTIONED IN THE SYNOPSIS ABOVE...THE MAIN FORECAST DILEMMA
FOR THE SHORT TERM IS THE POTENTIAL FOR PERIODS OF HEAVY RAINFALL
ALONG THE COAST ASSOCIATED WITH A WEAK AREA OF LOW PRESSURE MOVING
NORTHWARD THROUGH THE CENTRAL/EASTERN GULF. ALREADY SEEING LOTS OF
STORMS ACROSS THE EASTERN GULF OF MEXICO ASSOCIATED WITH THIS
SYSTEM...AND THESE WILL BE APPROACHING THE COAST LATER THIS
MORNING. ALMOST ALL THE GUIDANCE SUGGESTS A VERY CLOSE CALL AS TO
WHETHER OR NOT THE HEAVIER AND MORE PROLONGED RAINFALL REACHES THE
COAST OR STAYS JUST OFFSHORE. THE ISSUE AT HAND IS THAT IF THE
STORM TRACKS A BIT FURTHER EAST AND THE BANDS BECOME ESTABLISHED
ALONG THE COAST...THE AVAILABLE MOISTURE IN THE COLUMN IS VERY
HIGH...AND THE SQUALLS/BANDS ARE LIKELY TO BE VERY EFFICIENT AT
PRODUCING HEAVY RAINFALL. THERE IS UNCERTAINTY IN THIS FORECAST
DUE TO THE LIKELY TIGHT SPATIAL GRADIENT IN RAINFALL...BUT THE
POTENTIAL FOR SOME LOCATIONS TO SEE HEFTY RAINFALL AMOUNTS...
COMBINED WITH ALREADY ELEVATED RIVER LEVELS...WARRANTS THE
ISSUANCE OF A FLOOD WATCH. THIS FLOOD WATCH IS FOR ONLY THE
COASTAL COUNTIES FROM SARASOTA NORTHWARD TO LEVY. PERHAPS WE WILL
LUCK OUT AND THE FLOODING TYPE RAINS TEASE US JUST OFFSHORE...AND
NEVER REALLY MAKE IT TO OUR LAND ZONES. WILL BE MONITORING RADAR
AND NWP GUIDANCE TRENDS. EVEN IF "HEAVY" RAINFALL TOTALS DO NOT
MATERIALIZE...THE RAIN CHANCES ARE GOING TO BE HIGH FOR THE REGION
DUE TO BOTH THE GULF LOW...AND THE HIGH COLUMN MOISTURE FORCING
DIURNALLY PRODUCED STORMS. THEREFORE...MOST LOCATIONS ARE
FORECAST WITH LIKELY POPS. DEPENDING ON THE EVOLUTION OF THE
BANDS...MAY VERY WELL HAVE TO FURTHER INCREASE THESE RAIN CHANCES
TO CATEGORICAL ACROSS THE FLOOD WATCH AREA WITH FUTURE FORECAST
UPDATES. AT LEAST FOR NOW...MOST OF THE MORNING SHOULD BE ON THE
DRY SIDE...OUTSIDE OF A FEW ISOLATED SPRINKLES. THE REAL THREAT
FOR HEAVY RAINFALL (IF IT MATERIALIZES) WILL BE LATER THIS
AFTERNOON INTO TONIGHT.
DO NOT EXPECT MUCH IN THE WAY OF SUN TODAY...DEEP TROPICAL
MOISTURE WILL BE STREAMING OVERHEAD ALL DAY...KEEPING OUR SKIES
MOSTLY CLOUDY. THESE CLOUDS WILL ALSO KEEP TEMPERATURES DOWN IN
THE 80S FOR MOST SPOTS TODAY.
THE MAJORITY OF THE GUIDANCE GIVES THE BEST PUSH OF RAIN/STORM
POTENTIAL ASSOCIATED WITH THE LOW INTO THE COASTAL AREAS TONIGHT.
THE HIGH POPS OF LIKELY TO CATEGORICAL WILL CONTINUE ALONG THE
COAST. LATE TONIGHT...CONDITIONS IN THE LOWER LEVELS OVER THE
NORTHEAST GULF OF MEXICO AND ALONG THE COAST FROM TAMPA NORTHWARD
WILL FEATURE DECENT VALUES BETWEEN 20-25KTS OF 0-1KM AND 0-3KM
SHEAR. WILL HAVE TO MONITOR STORMS APPROACHING THE COAST VERY
CLOSELY...AS THIS SHEAR WILL HELP INDUCE SOME ROTATION/ENHANCED
UPDRAFTS. IT DOES APPEAR THAT CONDITIONS WILL SUPPORT A SMALL
THREAT FOR A FEW WATERSPOUTS OR WEAK TORNADOES WITH STRONGER
STORM MOVING ASHORE. WILL BE WATCHING THIS POTENTIAL WITH LATER
GUIDANCE PACKAGES. HOWEVER...WIDESPREAD SEVERE WEATHER IS NOT
EXPECTED...AND HOPEFULLY ANY ROTATING STORM WILL BE ISOLATED IN
NATURE...AND REMAIN OFFSHORE.
TUESDAY THE LOW IS EXPECTED TO MOVE ASHORE NEAR THE FLORIDA
PANHANDLE...WEAKEN AND EVENTUALLY SHEAR OUT TO OUR NORTH. AS THE
LOW GOES BY OUR LATITUDES...THE FLOW WILL VEER TO THE SOUTHWEST
THROUGH A DEEP LAYER OF THE ATMOSPHERE. THIS SOUTHWEST FLOW AND
STILL VERY HIGH COLUMN MOISTURE WILL CONTINUE TO HELP PROMOTE
SHOWERS AND STORMS TO MOVE ASHORE ALONG WESTERN FLORIDA. THE BANDS
DO NOT LOOK TO BE AS WIDESPREAD ON TUESDAY AS THEY MAY BE LATER
TODAY AND TONIGHT...HOWEVER...SMALLER SCALE CONVERGENCE ZONES
WOULD SUGGEST THE THREAT FOR LOCALIZED TRAINING OF STORMS OVER
CERTAIN LOCATIONS. THEREFORE...THE FLOOD WATCH WILL BE ALLOWED TO
CONTINUE INTO EARLY TUESDAY AFTERNOON. LATER IN THE DAY
TUESDAY...THERE ARE SOME INDICATIONS THAT THINGS MAY TRY TO DRY
OUT ACROSS THE NATURE COAST...AND HAVE TRENDED POPS DOWN TO THE
NORTH OF THE I-4 CORRIDOR AFTER 18Z. BETTER CHANCES FOR CONTINUED
SHOWERS OFF THE GULF WILL BE FROM TAMPA SOUTHWARD ALONG THE
SUNCOAST.
IT IS HIGHLY LIKELY THAT MOST AREAS WILL SEE A WETTING RAIN DURING
THE NEXT 24 TO 30 HOURS. HOWEVER...INLAND AREA WILL EXPERIENCE
MORE OF A SUMMER-LIKE PATTERN OF PASSING SHOWER AND STORMS. IT IS
THE IMMEDIATE COAST WHERE THE THREAT FOR PROLONGED RAIN LOOKS
HIGHEST. HAVE A GREAT MONDAY EVERYONE!
&&
.LONG TERM (WEDNESDAY THROUGH NEXT SUNDAY)...
U/L TROUGH WILL PERSIST OVER THE EASTERN U.S. WEDNESDAY...WITH S/W
ENERGY DIGGING THROUGH THE OHIO RIVER VALLEY THURSDAY REINFORCING
THE TROUGH OVER THE REGION. NEXT UPSTREAM S/W WILL DIG FURTHER WEST
OVER THE CENTRAL ROCKIES WHICH WILL KICK OUT THE TROUGH OVER THE
SOUTHEAST...WITH ZONAL U/L FLOW DEVELOPING ACROSS THE SOUTHERN TIER
OF THE U.S. SATURDAY AND SUNDAY.
AT THE SURFACE...AREA OF LOW PRESSURE WILL BE OFF THE SOUTHEAST U.S.
COAST WEDNESDAY WITH BOUNDARY EXTENDING ACROSS SOUTH FLORIDA WITH
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS OVER THE CENTRAL AND
SOUTHERN FORECAST AREA...WITH GREATEST AREAL COVERAGE OVER SOUTHWEST
FLORIDA. DEEP TROPICAL MOISTURE WILL REMAIN OVER THE REGION WITH
PCPW VALUES ABOVE 2 INCHES ACROSS THE CENTRAL AND SOUTHERN PENINSULA
WHICH WILL CONTINUE THE THREAT FOR LOCALLY HEAVY RAIN. SIMILAR SET-
UP ON THURSDAY HOWEVER THE DEEP LAYER MOISTURE WILL SLOWLY BE
SUPPRESSED TO THE SOUTH THROUGH THE DAY. THE AREA OF LOW PRESSURE
OFF THE SOUTHEAST COAST WILL LIFT SLOWLY OUT FRIDAY NIGHT AND
SATURDAY WITH DRIER AIR SURFACE AND ALOFT ADVECTING DOWN THE
BACKSIDE OVER WEST CENTRAL AND SOUTHWEST FLORIDA OVER THE
WEEKEND...WITH DEW POINTS DROPPING INTO THE 60S AND SLIGHTLY COOLER
TEMPERATURES.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS WEST-CENTRAL AND SOUTHWEST FLORIDA
EARLY THIS MORNING. OTHER THAN SOME LIGHT SPRINKLES...ANY
SIGNIFICANT RAINFALL SHOULD STAY OFFSHORE THROUGH 15Z. THEREAFTER
INCREASING CHANCES FOR SHOWER AND STORMS WILL ENTER THE FORECAST
FOR ALL TAF SITES. THE BEST POTENTIAL FOR LONGER DURATION RAINFALL
WILL BE AT KTPA/KPIE/KSRQ AFTER 16Z. PERIODIC SHOWER AND STORMS
WILL MOVE ASHORE FROM THE GULF OF MEXICO INTO TUESDAY MORNING WITH
MVFR CIG/VIS RESTRICTIONS ACCOMPANYING THE BANDS.
&&
.MARINE...
A WEAK AREA OF LOW PRESSURE WILL MOVE NORTHWARD THROUGH THE
CENTRAL AND EASTERN GULF OF MEXICO THROUGH TONIGHT. SOUTHEAST TO
SOUTH WINDS TO THE EAST OF THIS LOW WILL REACH CAUTIONARY LEVELS
AT TIMES THROUGH TONIGHT...ESPECIALLY AWAY FROM THE COAST. IN
ADDITION NUMEROUS SHOWER AND THUNDERSTORM SQUALL ARE EXPECTED
OVER THE COASTAL WATERS WHERE WIND AND SEAS MY BE MORE ROUGH. THE
LOW WILL WEAKEN AND MOVE AWAY FROM THE REGION LATE TUESDAY INTO
WEDNESDAY...WITH A LIGHTER WEST OR SOUTHWEST FLOW DEVELOPING
ACROSS THE EASTERN GULF OF MEXICO.
&&
.FIRE WEATHER...
THE FORECAST WILL FEATURE ABUNDANT LOW LEVEL MOISTURE THROUGH THE
EARLY PORTION OF THE WEEK. RELATIVE HUMIDITY VALUES WILL BE WELL
ABOVE CRITICAL VALUES AND MOST SPOTS WILL RECEIVE WETTING
RAINFALL BOTH MONDAY AND TUESDAY. THE HEAVIEST RAINFALL AND
LONGEST DURATION RAINFALL IS LIKELY TO BE ALONG THE IMMEDIATE
COAST THE NEXT COUPLE OF DAYS.
FOG POTENTIAL...
NO SIGNIFICANT FOG OR REDUCED VISIBILITY IS EXPECTED THE NEXT
SEVERAL DAYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 86 76 86 77 / 60 60 70 30
FMY 89 77 87 75 / 50 50 60 40
GIF 88 75 87 75 / 60 50 60 30
SRQ 85 78 85 77 / 60 70 70 30
BKV 86 74 86 74 / 70 60 70 30
SPG 86 77 85 78 / 60 70 70 40
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...FLOOD WATCH FROM 2 PM EDT THIS AFTERNOON THROUGH TUESDAY
AFTERNOON FOR COASTAL CITRUS-COASTAL HERNANDO-COASTAL
HILLSBOROUGH-COASTAL LEVY-COASTAL MANATEE-COASTAL
PASCO-COASTAL SARASOTA-INLAND CITRUS-INLAND HERNANDO-
INLAND HILLSBOROUGH-INLAND LEVY-INLAND MANATEE-INLAND
PASCO-INLAND SARASOTA-PINELLAS.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...MROCZKA
LONG TERM...13/OGLESBY
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
331 AM EDT MON SEP 28 2015
...Flash Flood Watch Now in Effect for Parts of the Region...
.Near Term [Through Today]...
The 1 am EDT regional surface analysis, with the help of a midnight
ASCAT pass, showed an elongated cyclonic circulation centered
roughly 100 miles north of the Yucatan Peninsula. The nearest deep
moist convection remained 100 miles east of the ill-defined center,
owing to 30 KT of southwest shear over this region. There was
another weak low centered off the TX-LA coast, associated with a mid-
upper tropospheric low over east TX. A zone of frontogenesis
extended east of this low across central FL. Vapor imagery and upper
air data showed deep southerly flow from the western Caribbean Sea
through our forecast area, with precip water values 50% above climo.
The forecast challenge today isn`t will it rain, but how much. The
global models` highest QPF values are south and west of our forecast
area. While our local ensemble of Convection Allowing Models (ECAM)
show this as well to some degree, they still forecast high QPF
values across our FL zones. It appears that the global models are
precipitating out most of the tropospheric moisture along the
developing east-west frontal boundary, while the CAMs allow
convection to occur north of this boundary. The ECAM has shown
considerable skill at forecasting heavy rain events in our region
the past few years, and we have followed it closely for this
forecast. Based on this, we will issue a Flash Flood Watch for the
southern half of our forecast area. We are forecasting a storm total
of 2 to 4 inches in this region, but isolated amounts could reach
8 inches. The bulk of this rain will occur today and tonight.
The 0-1 km vertical bulk shear and SBCAPE will be sufficient for
relatively shallow, "mini-supercells" over the Gulf coastal waters
today, capable of producing damaging wind gusts and even isolated,
brief tornadoes. This threat will gradually spread to the coast and
just inland, but storms will likely become elevated in GA and AL,
where the threat is lower.
.Short Term [Tonight Through Wednesday]...
The upper low near the northwest Gulf Coast will begin to move east
and open up during this period. The approaching surface low that has
garnered so much attention should lift northeast across the FL
Panhandle coast somewhere between Apalachicola and Pensacola Tuesday
morning. Categorical PoPs and areas of heavy rain will continue
through much of the night along with the flash flood threat,
particularly if we can get a north-south oriented band to set up.
The low will then further weaken as it tracks northeast across the
forecast area on Tuesday. This should end the flood threat. A cold
front will approach from the northwest on Wednesday maintaining PoPs
across the region, albeit lower than what we will see in the near
term.
.Long Term [Wednesday Night Through Monday]...
A long wave trough will remain over the Southeast through the end of
the work week and then pivot off to the northeast for the weekend.
The front will also finally push through the area by that time
setting us up for a classic October weekend, weather wise. Look for
negligible PoPs from Friday night onward with max temps in the
upper 70s to lower 80s and mins in the lower 60s.
&&
.Aviation...
[Through 06Z Tuesday] GFS/NAM MOS continue to maintain IFR or lower
cigs through the period, while the HRRR and other high-resolution
NWP guidance have mainly MVFR levels. Our forecast is a compromise,
with predominantly low-end MVFR cigs (1-2k ft AGL) through the
period. Periods of light to moderate RA are expected at all
terminals, beginning at KECP early, eventually reaching KABY and
KVLD later this afternoon. Brief periods of heavy rain with IFR
vis/cigs as well as TSRA are also expected through tonight.
&&
.Marine...
We are still not quite getting into solid advisory conditions and
we will let the exercise caution headline take care of things for
the time being. Obviously if the approaching low gets stronger
than anticipated, advisories will become necessary.
&&
.Fire Weather...
Wet flag conditions are likely through Tuesday, making controlled
burns nearly impossible.
&&
.Hydrology...
For a QPF discussion, reference the near-term section above. With
the heaviest amounts predicted nearer to the coast, area rivers will
be able to handle this event without reaching flood stage given the
recent dry conditions. With current streamflows, we`d need several
inches of rain to get into the upper portions of many of the larger
rivers and streams to produce river flooding, which still do not
anticipate during this particular event.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 82 74 86 73 88 / 80 80 60 30 40
Panama City 81 75 83 75 85 / 100 80 50 30 40
Dothan 78 70 82 69 85 / 80 80 60 40 50
Albany 81 72 83 71 85 / 80 80 70 40 50
Valdosta 83 72 84 72 85 / 70 70 70 30 40
Cross City 85 74 85 75 86 / 80 70 70 30 40
Apalachicola 81 73 84 72 85 / 100 80 50 30 40
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...FLASH FLOOD WATCH through Tuesday morning FOR Calhoun-Central
Walton-Coastal Bay-Coastal Dixie-Coastal Franklin-Coastal
Gulf-Coastal Jefferson-Coastal Taylor-Coastal Wakulla-
Gadsden-Holmes-Inland Bay-Inland Dixie-Inland Franklin-
Inland Gulf-Inland Jefferson-Inland Taylor-Inland Wakulla-
Jackson-Lafayette-Leon-Liberty-Madison-North Walton-South
Walton-Washington.
GA...FLASH FLOOD WATCH through Tuesday morning FOR Brooks-Decatur-
Grady-Lowndes-Seminole-Thomas.
AL...FLASH FLOOD WATCH through Tuesday morning FOR Geneva-Houston.
GM...NONE.
&&
$$
NEAR TERM...FOURNIER
SHORT TERM...WOOL
LONG TERM...WOOL
AVIATION...FOURNIER
MARINE...WOOL
FIRE WEATHER...WOOL
HYDROLOGY...GODSEY
AREA FORECAST DISCUSSION
NWS LINCOLN IL
603 PM CDT MON SEP 28 2015
.SHORT TERM...(TONIGHT)
ISSUED AT 252 PM CDT MON SEP 28 2015
Original shield of lower clouds has been contracting throughout the
day, and was basically limited to areas from Peoria to Chicago this
afternoon. Remainder of the CWA has seen clouds more of a diurnal
nature, which has allowed enough sunshine to get temperatures into
the lower 80s. So far the showers have remained extremely isolated.
Precipitation threat for the forecast area tonight will be coming
from a couple different directions. Across the southeast CWA, some
upper level energy will continue to surge northward up the
Mississippi River as the upper low over east Texas lifts northeast
and starts to open up. Showers should remain isolated this evening,
before rain chances start to ramp up late night as the energy gets
closer. Could be a rumble or two of thunder in the far southeast
late tonight, as the RAP shows lifted index values falling to near
zero, but chance is too small at the moment to include in the
forecast. Across the northwest CWA, the main player will be the cold
front which currently is pushing through northwest Iowa. Arrival of
the frontal boundary will be after 3 AM, and most of the rain will
be post-frontal, so will only carry some slight 20-30% PoP`s
northwest of the Illinois River late tonight.
.LONG TERM...(Tuesday THROUGH Monday)
ISSUED AT 252 PM CDT MON SEP 28 2015
A cold front will cross from near I-72 to start the day Tuesday to
near the southern tip of Illinois by evening. At the same time, low
pressure over the south central states will drift toward the
southeastern U.S., helping to combine enough moisture, lift, and
instability into mainly the southern half of Illinois for showers
and isolated thunderstorms. As a result...keeping chances for
showers/isolated thunder south of I-72 for Tuesday...with chances of
showers diminishing to the north through the day. Highs will
feature a strong gradient across central IL, ranging from the upper
60s in Galesburg to near 80 in Lawrenceville as cooler and drier air
moves in behind the front. Dewpoints in the low to mid 60s to start
the day to slip into the low to mid 50s behind the front over
northern counties Tue afternoon. Breezy north-northeast winds behind
the front will increase...reaching 10-15 mph with gusts into the 20
mph range.
Fairly persistent high pressure will settle into the Great Lakes
Region for the remainder of the work week...promoting an extended
period of breezy northeast winds and mostly sunny skies. Highs will
be in the upper 60s and low 70s through Friday with lows mainly in
40s.
There remains fairly poor model agreement over the weekend into
early next week...with a weak trough passing through the region in
the GFS...but a building ridge into the Plains and upper Midwest in
the ECMWF. Neither would have a good chance for precipitation and
forecast is therefore dry. Both would feature lighter winds.
Temperatures likely will feature minimal trend through the weekend
and kept highs in the 60s and lows mid-upper 40s.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z Tuesday EVENING)
ISSUED AT 603 PM CDT MON SEP 28 2015
Lots of mid clouds around 8kft still over the area, but based on
observation trends and satellite loops, believe the lower mid
clouds will dissipate quickly this evening and leave higher mid
clouds or high clouds over the area remainder of the night. So
will go with mid clouds around 12-15kft for the night with light
and variable winds. Then tomorrow, after the front has moved
through, scattered showers will be possible at all sites and winds
will increase out of the north-northeast...behind the front. With
light pcpn and vis decreasing, expecting MVFR cigs below 3kft at
all sites during the day tomorrow.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Geelhart
LONG TERM...Onton
AVIATION...Auten
AREA FORECAST DISCUSSION
NWS LINCOLN IL
252 PM CDT MON SEP 28 2015
.SHORT TERM...(TONIGHT)
ISSUED AT 252 PM CDT MON SEP 28 2015
Original shield of lower clouds has been contracting throughout the
day, and was basically limited to areas from Peoria to Chicago this
afternoon. Remainder of the CWA has seen clouds more of a diurnal
nature, which has allowed enough sunshine to get temperatures into
the lower 80s. So far the showers have remained extremely isolated.
Precipitation threat for the forecast area tonight will be coming
from a couple different directions. Across the southeast CWA, some
upper level energy will continue to surge northward up the
Mississippi River as the upper low over east Texas lifts northeast
and starts to open up. Showers should remain isolated this evening,
before rain chances start to ramp up late night as the energy gets
closer. Could be a rumble or two of thunder in the far southeast
late tonight, as the RAP shows lifted index values falling to near
zero, but chance is too small at the moment to include in the
forecast. Across the northwest CWA, the main player will be the cold
front which currently is pushing through northwest Iowa. Arrival of
the frontal boundary will be after 3 AM, and most of the rain will
be post-frontal, so will only carry some slight 20-30% PoP`s
northwest of the Illinois River late tonight.
&&
.LONG TERM...(Tuesday THROUGH Monday)
ISSUED AT 252 PM CDT MON SEP 28 2015
A cold front will cross from near I-72 to start the day Tuesday to
near the southern tip of Illinois by evening. At the same time, low
pressure over the south central states will drift toward the
southeastern U.S., helping to combine enough moisture, lift, and
instability into mainly the southern half of Illinois for showers
and isolated thunderstorms. As a result...keeping chances for
showers/isolated thunder south of I-72 for Tuesday...with chances of
showers diminishing to the north through the day. Highs will
feature a strong gradient across central IL, ranging from the upper
60s in Galesburg to near 80 in Lawrenceville as cooler and drier air
moves in behind the front. Dewpoints in the low to mid 60s to start
the day to slip into the low to mid 50s behind the front over
northern counties Tue afternoon. Breezy north-northeast winds behind
the front will increase...reaching 10-15 mph with gusts into the 20
mph range.
Fairly persistent high pressure will settle into the Great Lakes
Region for the remainder of the work week...promoting an extended
period of breezy northeast winds and mostly sunny skies. Highs will
be in the upper 60s and low 70s through Friday with lows mainly in
40s.
There remains fairly poor model agreement over the weekend into
early next week...with a weak trough passing through the region in
the GFS...but a building ridge into the Plains and upper Midwest in
the ECMWF. Neither would have a good chance for precipitation and
forecast is therefore dry. Both would feature lighter winds.
Temperatures likely will feature minimal trend through the weekend
and kept highs in the 60s and lows mid-upper 40s.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z Tuesday AFTERNOON)
ISSUED AT 1225 PM CDT MON SEP 28 2015
Still a bit of MVFR conditions lingering around KBMI/KPIA, but
this area continues to contract and ceilings will lift over the
next couple hours. Main concern will be in the period after 10Z,
when a cold front arrives from the northwest. Ceilings expected to
fall below 3,000 feet with the arrival of the front, and remain
that way the remainder of the forecast period. A few showers may
precede the front, but most will be after its passage. Winds
expected to shift to the north-northeast and increase to near 10
knots Tuesday morning behind the front.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Geelhart
LONG TERM...Onton
AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1151 PM CDT SUN SEP 27 2015
.UPDATE...
ISSUED AT 900 PM CDT SUN SEP 27 2015
Still a lot of clouds over the area but see some breaks in the
east. Not enough breaks to make me want to change the sky cover
forecast as still expecting mostly cloudy skies. If skies become
more partly cloudy later, then will have to update then...just not
yet. Overall forecast looks good this evening and see no reason to
update at this time.
&&
.SHORT TERM...(TONIGHT)
ISSUED AT 246 PM CDT SUN SEP 27 2015
Cloud cover remains fairly extensive across the area today, with the
earlier breaks near the I-74 corridor quickly filling in late
morning with diurnal cumulus. A few showers have been tracking
northwest out of southern Illinois, associated with what is left of
the upper low over the Tennessee Valley.
Forecast soundings not really showing much in the way of clearing
this evening, with skies mainly partly to mostly cloudy. A feature
of interest is overnight, with the last few runs of the RAP showing
a surge of stratus advecting northeast into our area after midnight
and covering most of the state, along with some dense fog late in
the night. The latest NAM model favors more of a patchy fog
scenario, which would seem more likely given the lack of widespread
clearing plus not much of a wind field to advect the low clouds into
this area, so will continue with mention of patchy fog for now.
.LONG TERM...(Monday THROUGH Sunday)
ISSUED AT 246 PM CDT SUN SEP 27 2015
While by no means certain at this point, a bit more clarity has
started to develop in the forecast for the remainder of the week.
Above normal temperatures are expected to linger for a couple more
days, then trend toward normal in the wake of Tuesday`s cold front,
with below normal temperatures possible by the weekend as some
degree of upper troffing develops across eastern North America. The
model consensus has also trended back toward a drier solution for
the week, with the best chances of rainfall occurring in the
vicinity of the frontal passage on Tuesday.
Maintained a very low chance for rainfall on Monday as weak
disturbances track northeast up the Ohio River Valley from the Gulf
of Mexico. However, the very modest forcing and instability support
little more than we are currently seeing across southern Illinois
today as far as coverage and intensity.
A cold front, currently extending from northern Ontario into the
central Plains, will sink southeast across the forecast area later
Monday night into Tuesday. This front will not have much going for
it as far as support for precipitation production. The best forcing
will remain across Canada with the faster upper-level flow, with the
best moisture bottled up with a system along the Gulf coast. So,
plan to keep PoPs on the low side with fropa, and it is entirely
possible that most locations will remain dry. However, this appears
to be our best shot for widespread rainfall this week.
A Canadian surface high builds into the area behind the cold front,
which should help shave several degrees of the daily max/min
temperatures. Aloft, the flow across North America is expected to
transition from mostly zonal to more of a troffy pattern. However,
exactly how the upper pattern will look by late week and how we`ll
get there is still very much up for debate. Model spread remain
significant, with the spaghetti plots looking much like a pile of
spaghetti. There does not appear to be a strong signal for rainfall
at any one time, although there is some consensus that it is
possible over the weekend. Expect the weekend to be more dry than
not, but there will certainly be some risk of rain. We`ll have to
see how the models eventually resolve the coming pattern shift to
pin point the threat better.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z Monday NIGHT)
ISSUED AT 1151 PM CDT SUN SEP 27 2015
Still plenty of clouds around the area this evening and am
expecting them to continue overnight. Some breaks in the east and
northeast, but am expecting them to be filled in next couple of
hours after TAF issuance time. HiRes models continue to show lower
MVFR clouds and an increase in fog across the area, and this
seems somewhat reasonable given we had some light showers move
across the area earlier this evening. Guidance also gives IFR
clouds during early morning hours and since winds are lighter and
we have had some breaks in the clouds, dewpoints have come up so
believe this is possible. So will have MVFR cigs with some light
fog later tonight and add a TEMPO group for a few hours during the
morning with cigs below 1kft and vis below 2sm. Things should
improve during the later morning with VFR cigs around 4kft. Then
during the evening, expecting lower clouds to dissipate and just
have cirrus clouds. Winds will be southeast and then become
south to southwest tomorrow...then light and variable tomorrow
evening.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Auten
SHORT TERM...Geelhart
LONG TERM...Bak
AVIATION...Auten
AREA FORECAST DISCUSSION
NWS PADUCAH KY
842 PM CDT TUE SEP 29 2015
.UPDATE...
Issued at 829 PM CDT TUE SEP 29 2015
For aviation section only.
&&
.SHORT TERM...(This evening through Thursday Night)
Issued at 1251 PM CDT TUE SEP 29 2015
Fairly high confidence in the short term.
As usual patchy fog tonight is very difficult especially with a
north wind expected to stay up all night. The MOS data suggests at
least some patchy fog across the area with isolated areas of dense
fog mainly in Cape Girardeau. This is not unusual for the models
to advertise this fog after a rain event but it is not typical
with a north wind and clouds all night. This will be one parameter
we will have to monitor closely. The HRRR indicates an upper low
was meandering over confluence of the Ohio and Mississippi Rivers
most of the morning then it slowly lifts it toward EVV this aftn.
Current radar trends would support this scenario. Could see more
rain but should remain light and scattered at best. The upper
level wave will bisect the heartland around midnight and pass east
early Wednesday morning. Cleared the mention of rain in the wake
of this trough. After today cooler and drier air will filter into
the region with temperatures close to 10 degrees below normal for
highs and lows.
.LONG TERM...(Friday through Tuesday)
Issued at 1251 PM CDT TUE SEP 29 2015
At the start of the extended period, we will dealing with what
happens with an upper level low, which develops over the CWA
Wednesday night into Thursday. Medium range models suggest that by
12Z Friday, the upper low should be in Alabama, so our area should
remain rain free. We will likely be dealing with some cloudiness
(especially east) however and cool temperatures.
As we head into the weekend, this feature eventually moves east and
then northeast up the eastern seaboard, although models are in
disagreement on how fast and in what direction it will head. This
will mean continued cool temperatures and some cloudy conditions
from time to time until this system moves far enough east to not
impact our area. This will probably happen sometime late in the
weekend.
By early next week, we should see upper heights rising which will
mean an uptick in temperatures.
&&
.AVIATION...
Issued at 829 PM CDT TUE SEP 29 2015
Think models are over doing Low IFR conditions later tonight into
tomorrow morning. Will go with MVFR cigs during the evening then
allow some drizzle and IFR conditions to work in after midnight.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
UPDATE...GM
SHORT TERM...KH
LONG TERM...CW
AVIATION...GM
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
117 PM CDT MON SEP 28 2015
.AVIATION...
CIGS CONTINUE TO LIFT ACROSS THE REGION THIS AFTERNOON...AND MOST
SITES ARE NOW IN THE VFR FLIGHT CATEGORY. THIS IS EXPECTED TO
CONTINUE THROUGH THE DAY AND INTO THE OVERNIGHT HOURS...BEFORE
MORE STRATUS DEVELOPS AFTER 06Z. WE MAY SEE SOME IMPROVEMENT FOR
THOSE SITES THAT DO SEE STRATUS PRIOR TO THE END OF THE PD...BUT
CIGS WILL MOST LIKELY HANG IN THROUGH 18Z TUESDAY. ADDITIONALLY...UPPER
LOW PRESSURE SYSTEM ALONG THE GULF COAST WILL KEEP THE POSSIBILITY
OF FOR ISOLD TO SCT SHWRS IN FOR OUR TERMINALS THROUGH MOST OF THE
PD. OTHERWISE...NELY WINDS 5-10 KTS ARE EXPECTED THROUGH THE PD.
/12/
&&
.PREV DISCUSSION... /ISSUED 1144 AM CDT MON SEP 28 2015/
UPDATE...
ADJUST POPS AND WEATHER FOR THE AFTERNOON...EVENING AND OVERNIGHT.
DISCUSSION...
VERY NICE AND COASTALLY HUMID WITH MID TO UPPER 70S. OUR SKIES
ARE MOSTLY CLOUDY TO CLOUDY WITH OUR RADAR FAIRLY QUIET AND
GETTING QUIETER. THE OCCASIONALLY CONVERGENT FORCING REMAINS GOOD
FOR SOME DEVELOPMENT TO UNFOLD WITH HEATING OF LOW TO MID 80S.
HOWEVER...OVERNIGHT MAY TURN OUT TO BE EVEN MORE PRODUCTIVE THAN
MODELED AT THIS TIME FOR THE EAST. SOME NEW 12Z DATA IS
ENCOURAGING ON HRRR AND NAM. AT ANY RATE THIS SYSTEM IS OCCLUDED
AND SURROUNDING ITSELF WITH DRY AIR...CUT OFF NOW FROM THE RICH
TROPICAL CONNECTION OF YESTERDAY. RAINFALL AMOUNTS WILL BE TOO
LIGHT FOR MOST EVERYONE...BUT WITH LUCKY FEW POSSIBLY SEEING AN
INCH OR THREE. IN THE WAKE OF THE SYSTEM THE UPPER PATTERN WILL
FALL ALOFT HEIGHT WISE AT LEAST COOLING THE 90 DEGREE HEAT OF
LATE. A ZONAL PATTERN WILL ESTABLISH BY THE WEEKEND WITH ANOTHER
SLIGHT CHANCE FOR SOME PRECIP IN NEXT MONTHS BUCKET. /24/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 70 86 69 88 / 30 40 20 10
MLU 69 85 68 87 / 50 40 20 20
DEQ 66 85 65 87 / 20 30 20 0
TXK 68 84 67 86 / 30 40 20 0
ELD 67 84 66 85 / 40 40 20 10
TYR 69 87 69 89 / 20 30 20 0
GGG 68 86 68 89 / 30 40 20 10
LFK 67 85 68 89 / 30 40 20 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
12
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1144 AM CDT MON SEP 28 2015
.UPDATE...
ADJUST POPS AND WEATHER FOR THE AFTERNOON...EVENING AND OVERNIGHT.
&&
.DISCUSSION...
VERY NICE AND COASTALLY HUMID WITH MID TO UPPER 70S. OUR SKIES
ARE MOSTLY CLOUDY TO CLOUDY WITH OUR RADAR FAIRLY QUIET AND
GETTING QUIETER. THE OCCASIONALLY CONVERGENT FORCING REMAINS GOOD
FOR SOME DEVELOPMENT TO UNFOLD WITH HEATING OF LOW TO MID 80S.
HOWEVER...OVERNIGHT MAY TURN OUT TO BE EVEN MORE PRODUCTIVE THAN
MODELED AT THIS TIME FOR THE EAST. SOME NEW 12Z DATA IS
ENCOURAGING ON HRRR AND NAM. AT ANY RATE THIS SYSTEM IS OCCLUDED
AND SURROUNDING ITSELF WITH DRY AIR...CUT OFF NOW FROM THE RICH
TROPICAL CONNECTION OF YESTERDAY. RAINFALL AMOUNTS WILL BE TOO
LIGHT FOR MOST EVERYONE...BUT WITH LUCKY FEW POSSIBLY SEEING AN
INCH OR THREE. IN THE WAKE OF THE SYSTEM THE UPPER PATTERN WILL
FALL ALOFT HEIGHT WISE AT LEAST COOLING THE 90 DEGREE HEAT OF
LATE. A ZONAL PATTERN WILL ESTABLISH BY THE WEEKEND WITH ANOTHER
SLIGHT CHANCE FOR SOME PRECIP IN NEXT MONTHS BUCKET. /24/
&&
.PREV DISCUSSION... /ISSUED 634 AM CDT MON SEP 28 2015/
AVIATION...
UPPER-LEVEL DISTURBANCE TO ALLOW FOR VCTS CONDITIONS ACROSS AREA
TERMINALS TODAY. CONVECTION TO DIMINISH AFTER 29/00Z. MVR/IFR
CEILINGS AND VISIBILITES POSSIBLE ACROSS MOST TERMINAL SITES
AFTER 29/06Z. OTHERWISE...LIGHT NORTHEAST WINDS TO PREVAIL
THROUGH THE TERMINAL FORECAST PERIOD. /05/
&&
.PREV DISCUSSION... /ISSUED 421 AM CDT MON SEP 28 2015/
.DISCUSSION...
CUTOFF UPPER TROUGH IS CENTERED OVER THE TX COAST JUST SW OF
GALVESTON WHILE A SFC LOW IS LOCATED JUST TO THE EAST OF THE UPPER
TROUGH OVER THE NW GULF OF MEXICO. SHWRS/TSTMS MOVING CYCLONICALLY
AROUND THE TROUGH ARE GRADUALLY SPREADING NORTH INTO EAST TEXAS
AND THE TOLEDO BEND COUNTRY THIS MORNING. SCATTERED CONVECTION
SHOULD CONTINUE TO INCREASE IN COVERAGE AND SPREAD NORTH ACROSS
THE CWA TODAY ALTHOUGH THE HIGHEST RAIN CHANCES WILL BE ACROSS
DEEP EAST TEXAS AND INTO N CNTRL LA. LATEST WV VAPOR IMAGERY
INDICATES SOME MID LVL DRY AIR ENTRAINMENT ON THE ERN FLANK OF
THE TROUGH WHICH IS BEING DRAWN UP INTO ERN PORTIONS OF THE CWA.
HOWEVER...THE UPPER TROUGH IS EXPECTED TO SLOWLY DRIFT EAST ALONG
THE GULF COAST WHICH SHOULD DISPLACE THE DRIER AIR FARTHER EAST.
DIURNAL HEATING WILL FUEL A GREAT DEAL OF THE CONVECTION TODAY SO
MOST OF THE SHWRS/TSTMS SHOULD DIMINISH AFTER SUNSET ESPECIALLY
NORTH OF I-20. REDEVELOPMENT ACROSS MOST OF THE AREA IS LIKELY
AGAIN DURING THE DAY ON TUESDAY DURING PEAK HEATING BUT COVERAGE
MAY BE SOMEWHAT LESS AS THE TROUGH AXIS WILL BE EAST OF THE CWA. A
FEW SHWRS OR TSTMS MAY LINGER INTO WEDNESDAY SE OF A LINE FROM
KLFK TO KMLU BUT RAIN CHANCES SHOULD QUICKLY COME TO AN END BY
LATE WEDNESDAY AFTERNOON.
AN UPPER RIDGE WILL BEGIN TO BUILD EAST INTO THE SRN PLAINS BUT
WILL FLATTEN THROUGH THE LATTER HALF OF THE WEEK. FLOW ALOFT WILL
TRANSITION TO NWLY BRINGING A COLD FRONT INTO THE AREA DURING THE
WEEKEND. NLY FLOW IN THE LOWEST LVLS WILL LIKELY KEEP GULF
MOISTURE CUT OFF FROM THE REGION SO CHANCES OF RAIN WITH THIS
FRONT DO NOT APPEAR VERY PROMISING AT THIS TIME. HOWEVER...WILL
MAINTAIN SLIGHT CHANCE POPS SATURDAY AND SUNDAY WITH THE FROPA.
THE AFOREMENTIONED LOW LVL DRY AIR THAT ARRIVES LATE
THURSDAY/EARLY FRIDAY...FOLLOWED BY THE REINFORCEMENT OF THE
COOLER/DRIER AIR BEHIND THE COLD FRONT DURING THE WEEKEND...SHOULD
KEEP TEMPERATURES VERY CLOSE TO SEASONAL NORMS FROM FRIDAY THROUGH
THE BEGINNING OF NEXT WEEK. /09/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 86 70 86 69 / 50 30 40 20
MLU 82 69 85 68 / 50 50 40 20
DEQ 85 66 85 65 / 30 20 30 20
TXK 84 68 84 67 / 40 30 40 20
ELD 83 67 84 66 / 40 40 40 20
TYR 86 69 87 69 / 40 20 30 20
GGG 85 68 86 68 / 40 30 40 20
LFK 84 67 85 68 / 50 30 40 20
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
24/05/09
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
534 PM EDT MON SEP 28 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 421 PM EDT MON SEP 28 2015
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A TROF PROGRESSING ACROSS
CNTRL CANADA. TROF IS SUPPORTING A PAIR OF SFC COLD FRONTS. FIRST IS
MOVING ACROSS CNTRL UPPER MI ATTM WHILE THE SECOND WHICH MARKS THE
LEADING EDGE OF THE NOTABLY COLDER AIR RUNS FROM JAMES BAY TO JUST W
OF LAKE SUPERIOR. IMPROVED UPPER DIVERGENCE ASSOCIATED WITH THE
RIGHT ENTRANCE OF UPPER JET AND LOW/MID LEVEL FGEN UNDERNEATH HAS
SUPPORTED AN EXPANSION OF SHRA AND A FEW TSRA ALONG/JUST BEHIND THE
LEAD COLD FRONT TODAY...THOUGH THERE HASN`T BEEN MUCH THUNDER THIS
AFTN AFTER AN INCREASE DURING THE MORNING.
MODELS ARE IN GOOD AGREEMENT PUSHING COLD FRONTS AND ASSOCIATED PCPN
S AND E THIS EVENING. WITH MODELS IN GOOD AGREEMENT ON PCPN
FIELDS...UTILIZED A COMBINATION OF MODEL CONSENSUS AND RADAR TRENDS
TO CONSTRUCT POP GRIDS THRU THE EVENING. LINGERING UPPER DIVERGENCE
ASSOCIATED WITH UPPER JET STREAK AS WELL AS SECOND SFC COLD FRONT
SWEEPING SE MAY GENERATE A FEW -SHRA BEHIND THE MAIN AREA OF PCPN
TIED MORE CLOSELY TO FIRST COLD FRONT. THUS...SOME LOW POPS WILL BE
CARRIED AS LATE AS THE MID TO LATE EVENING OVER THE FAR SCNTRL/SE.
OTHERWISE...COLDER AND MUCH DRIER AIR WILL FLOW INTO THE AREA
TONIGHT. 850MB TEMPS CURRENTLY AT 10-13C WILL FALL TO -1C OVER THE
KEWEENAW TO 7C FAR SCNTRL BY 12Z TUE. THIS WILL RESULT IN A MUCH
COOLER OVERNIGHT WITH MIN TEMPS DIPPING TO AROUND 40F AND PROBABLY
INTO THE UPPER 30S AT SOME HIER TERRAIN LOCATIONS OVER W AND NW
UPPER MI. HIGHEST MINS WILL BE NEAR LAKE MI...UPPER 40S/AROUND 50F.
ALTHOUGH THE SFC-850MB DELTA-T BTWN THE LAKE WATERS STILL IN THE
MID/UPR 50S F IS SUFFICIENT FOR LAKE CLOUDS/PCPN...FCST SOUNDINGS
SHOW THAT THE INCOMING AIR MASS WILL BE EXTREMELY DRY. SO...THE
CHILLY AIR FLOW OVER THE LAKE PROBABLY WON`T SUPPORT MUCH MORE THAN
SCT CLOUDS OVER THE HIER TERRAIN LATE TONIGHT.
850MB TEMPS BOTTOM OUT AT -1 TO -2C TUE MORNING. WITH FCST SOUNDINGS
STILL SHOWING A VERY DRY AIR MASS FLOWING INTO THE UPPER LAKES...NOT
EXPECTING MUCH IN THE WAY OF CLOUD COVER. IF ANYTHING...THE
MOISTENING PROVIDED BY THE LAKE MAY PROVIDE AN INCREASE IN CLOUD
COVER INLAND FOR A TIME IN THE MORNING AS DAYTIME HEATING WORKS ON
THE MOISTURE. SHOULDN`T BE ANYTHING MORE THAN SCT CLOUD COVER.
OTHERWISE...THE WEATHER WILL FEEL MUCH MORE LIKE FALL WITH HIGH
TEMPS IN THE MID 50S TO AROUND 60F AND A RATHER BRISK NW WIND...
ESPECIALLY OVER THE E HALF OF THE FCST AREA.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 533 PM EDT MON SEP 28 2015
HIGHS WILL MAINLY BE IN THE 50S FOR HIGHS THROUGH THE PERIOD...WHICH
WILL BE THE FIRST STRETCH OF BELOW NORMAL TEMPERATURES FOR QUITE A
WHILE /AT LEAST 10 DAYS/.
WE BEGIN AT 00Z WEDNESDAY WITH THE LARGE SFC HIGH ACROSS MUCH OF THE
UPPER GREAT LAKES...AND THE MAIN 500MB TROUGH EXTENDING FROM N
QUEBEC DOWN THROUGH LOWER MI AND THE MS DELTA. FOR UPPER MI
MAINLY ZONAL FLOW IS FIGURED ALOFT THROUGH 00Z THURSDAY.
DRY WEATHER WILL DOMINATE MUCH OF THIS PERIOD. THE MAIN WEATHER
THREAT WILL LIKELY BE THE COLD TUESDAY NIGHT INTO WEDNESDAY
MORNING...AND AGAIN WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING.
HAVE ISSUED A FREEZE WATCH FOR THE W HALF...MINUS THE KEWEENAW
PENINSULA. FROST ADVISORIES MAY BE POSTED FOR THE REST OF THE CWA IF
THE CURRENT FCST HOLDS TRUE. THIS WILL BE THANKS TO LOWS OF
27-35F...WITH THE LOWEST VALUES INLAND FROM LAKE SUPERIOR. STAY TUNED
AS WINDS WILL BE CALM...AND THE POTENTIAL EXISTS FOR TEMPS TO FALL
ANOTHER COUPLE OF DEGREES FROM THE CURRENT FCST. 850MB TEMPS WILL E
IN THE -1C RANGE OVER THE KEWEENAW E THROUGH THE N TIER COUNTIES...TO
AS WARM AS 1.5-3C OVER MENOMINEE COUNTY /WARMEST OFF THE GFS/.
FCST MODELS DO SHOW AN EMBEDDED SHORTWAVE/TROUGH SET UP ACROSS S
MANITOBA AT 00Z THURSDAY...BUT THE OVERALL STRENGTH IS DIFFERENT.
THE CONSENSUS IS THAT THIS FEATURE WILL GO ON ITS OWN...AND BEGIN TO
RETROGRADE...WITH RIDGING AT THE SFC AND ALOFT OVER THE UPPER GREAT
LAKES. ALTHOUGH THE MAIN SFC HIGH WILL SHIFT NE MORE INTO
QUEBEC...THE RIDGE WILL BE WELL ESTABLISHED OVERHEAD.
ONLY HAVE SLIGHT CHANCE POPS FOR THE KEWEENAW SUNDAY...AND MAINLY
JUST ALONG LAKE SUPERIOR SUNDAY NIGHT. THIS LOOKS REASONABLE...BUT
WILL NOT INCREASE THE POTENTIAL. MODELS ARE PRETTY CONSISTENT WITH
THE OVERALL PATTERN THROUGH WEDNESDAY EVENING. HOWEVER...THE GFS HAS
A DEEPER 500MB LOW OVER QUEBEC RETROGRADING AS CLOSE AS THE E HALF
OF QUEBEC BY 18Z SATURDAY. THE ECMWF IS NOT AS IMPRESSIVE AND IS
MORE FOCUSED ON THE S 500MB LOW SPINNING OVER THE SE STATES. WILL
KEEP A GENERAL BLEND UNTIL A MORE CONCRETE SOLUTION APPEARS. EITHER
WAY...COOL WEATHER AND A MAINLY N FLOW SHOULD REMAIN ACROSS UPPER
MI.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 201 PM EDT MON SEP 28 2015
A COLD FRONT OVER WRN UPPER MI WILL PASS THRU KSAW IN THE NEXT FEW
HRS. A SECONDARY COLD FRONT WILL THEN FOLLOW THIS EVENING AND
OVERNIGHT. -SHRA ASSOCIATED WITH THE FIRST COLD FRONT WILL AFFECT
KSAW FOR MUCH OF THE AFTN WITH MVFR CONDITIONS LIKELY PREVAILING FOR
THE NEXT FEW HRS. TO THE W...INCOMING DRIER AIR HAS ALREADY RESULTED
IN LOW CLOUDS CLEARING OUT AT KIWD/KCMX...AND VFR CONDITIONS WILL BE
THE RULE AT THOSE TERMINALS THIS AFTN. BEHIND THE SECOND COLD
FRONT...NW WINDS WILL INCREASE...ESPECIALLY AT KCMX WHERE WINDS WILL
LIKELY GUST TO AROUND 25KT. INCOMING CHILLY AIR MASS WILL BE VERY
DRY...SO NOT EXPECTING ANYTHING MORE THAN SCT LAKE EFFECT CLOUDS TO
DEVELOP LATE TONIGHT/TUE MORNING...ALLOWING VFR CONDITIONS TO
PREVAIL AT KIWD/KCMX/KSAW TONIGHT/TUE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 421 PM EDT MON SEP 28 2015
WITH ONE COLD FRONT EXITING LAKE SUPERIOR NOW...A SECOND COLD FRONT
WILL SWEEP ACROSS THE LAKE TONIGHT. PRES RISES ALONG WITH INCREASING
OVERWATER INSTABILITY AS COLDER AIR FLOWS INTO THE UPPER LAKES WILL
RESULT IN NW WINDS INCREASING TO 20-30KT TONIGHT AFTER THE SECOND
COLD FRONT PASSES. WHILE WINDS WILL REMAIN MOSTLY IN THE 20-30KT
RANGE OVER ERN LAKE SUPERIOR TUE...WINDS WILL DIMINISH OVER THE WRN
LAKE AS HIGH PRES APPROACHES. WINDS WILL THEN DIMINISH TO MOSTLY
UNDER 15KT W TO E TUE NIGHT/WED AS HIGH PRES SETTLES OVER THE UPPER
LAKES. AS THE HIGH DRIFTS TO THE ENE THRU THE END OF THE WEEK...IT
WILL EXTEND A RIDGE BACK TOWARD THE UPPER LAKES. SINCE IT LOOKS LIKE
THE RIDGE MAY BE SITUATED A LITTLE FARTHER N THAN PREVIOUSLY
EXPECTED...EASTERLY WINDS MAY BECOME BRISK INTO THE 15-25KT RANGE AT
TIMES DURING THE LATE WEEK PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING
FOR MIZ002-004-009-010-084.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
421 PM EDT MON SEP 28 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 421 PM EDT MON SEP 28 2015
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A TROF PROGRESSING ACROSS
CNTRL CANADA. TROF IS SUPPORTING A PAIR OF SFC COLD FRONTS. FIRST IS
MOVING ACROSS CNTRL UPPER MI ATTM WHILE THE SECOND WHICH MARKS THE
LEADING EDGE OF THE NOTABLY COLDER AIR RUNS FROM JAMES BAY TO JUST W
OF LAKE SUPERIOR. IMPROVED UPPER DIVERGENCE ASSOCIATED WITH THE
RIGHT ENTRANCE OF UPPER JET AND LOW/MID LEVEL FGEN UNDERNEATH HAS
SUPPORTED AN EXPANSION OF SHRA AND A FEW TSRA ALONG/JUST BEHIND THE
LEAD COLD FRONT TODAY...THOUGH THERE HASN`T BEEN MUCH THUNDER THIS
AFTN AFTER AN INCREASE DURING THE MORNING.
MODELS ARE IN GOOD AGREEMENT PUSHING COLD FRONTS AND ASSOCIATED PCPN
S AND E THIS EVENING. WITH MODELS IN GOOD AGREEMENT ON PCPN
FIELDS...UTILIZED A COMBINATION OF MODEL CONSENSUS AND RADAR TRENDS
TO CONSTRUCT POP GRIDS THRU THE EVENING. LINGERING UPPER DIVERGENCE
ASSOCIATED WITH UPPER JET STREAK AS WELL AS SECOND SFC COLD FRONT
SWEEPING SE MAY GENERATE A FEW -SHRA BEHIND THE MAIN AREA OF PCPN
TIED MORE CLOSELY TO FIRST COLD FRONT. THUS...SOME LOW POPS WILL BE
CARRIED AS LATE AS THE MID TO LATE EVENING OVER THE FAR SCNTRL/SE.
OTHERWISE...COLDER AND MUCH DRIER AIR WILL FLOW INTO THE AREA
TONIGHT. 850MB TEMPS CURRENTLY AT 10-13C WILL FALL TO -1C OVER THE
KEWEENAW TO 7C FAR SCNTRL BY 12Z TUE. THIS WILL RESULT IN A MUCH
COOLER OVERNIGHT WITH MIN TEMPS DIPPING TO AROUND 40F AND PROBABLY
INTO THE UPPER 30S AT SOME HIER TERRAIN LOCATIONS OVER W AND NW
UPPER MI. HIGHEST MINS WILL BE NEAR LAKE MI...UPPER 40S/AROUND 50F.
ALTHOUGH THE SFC-850MB DELTA-T BTWN THE LAKE WATERS STILL IN THE
MID/UPR 50S F IS SUFFICIENT FOR LAKE CLOUDS/PCPN...FCST SOUNDINGS
SHOW THAT THE INCOMING AIR MASS WILL BE EXTREMELY DRY. SO...THE
CHILLY AIR FLOW OVER THE LAKE PROBABLY WON`T SUPPORT MUCH MORE THAN
SCT CLOUDS OVER THE HIER TERRAIN LATE TONIGHT.
850MB TEMPS BOTTOM OUT AT -1 TO -2C TUE MORNING. WITH FCST SOUNDINGS
STILL SHOWING A VERY DRY AIR MASS FLOWING INTO THE UPPER LAKES...NOT
EXPECTING MUCH IN THE WAY OF CLOUD COVER. IF ANYTHING...THE
MOISTENING PROVIDED BY THE LAKE MAY PROVIDE AN INCREASE IN CLOUD
COVER INLAND FOR A TIME IN THE MORNING AS DAYTIME HEATING WORKS ON
THE MOISTURE. SHOULDN`T BE ANYTHING MORE THAN SCT CLOUD COVER.
OTHERWISE...THE WEATHER WILL FEEL MUCH MORE LIKE FALL WITH HIGH
TEMPS IN THE MID 50S TO AROUND 60F AND A RATHER BRISK NW WIND...
ESPECIALLY OVER THE E HALF OF THE FCST AREA.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 415 PM EDT MON SEP 28 2015
HIGHS WILL MAINLY BE IN THE 50S FOR HIGHS THROUGH THE PERIOD...WHICH
WILL BE THE FIRST STRETCH OF BELOW NORMAL TEMPERATURES FOR QUITE A
WHILE /AT LEAST 10 DAYS/.
WE BEGIN AT 00Z WEDNESDAY WITH THE LARGE SFC HIGH ACROSS MUCH OF THE
UPPER GREAT LAKES...AND THE MAIN 500MB TROUGH EXTENDING FROM N
QUEBEC DOWN THROUGH LOWER MI AND THE MS DELTA. FOR UPPER MI
MAINLY ZONAL FLOW IS FIGURED ALOFT THROUGH 00Z THURSDAY.
DRY WEATHER WILL DOMINATE MUCH OF THIS PERIOD. THE MAIN WEATHER
THREAT WILL LIKELY BE THE COLD TUESDAY NIGHT INTO WEDNESDAY
MORNING...AND AGAIN WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING.
HAVE ISSUED A FREEZE WATCH FOR THE W HALF...MINUS THE KEWEENAW
PENINSULA. WIND CHILL ADVISORIES MAY BE POSTED FOR THE REST OF THE
CWA IF THE CURRENT FCST HOLDS TRUE. THIS WILL BE THANKS TO LOWS OF
27-35F...WITH THE LOWEST VALUES INLAND FROM LAKE SUPERIOR. STAY
TUNED AS WINDS WILL BE CALM...AND THE POTENTIAL EXISTS FOR TEMPS TO
FALL ANOTHER COUPLE OF DEGREES FROM THE CURRENT FCST. 850MB TEMPS
WILL E IN THE -1C RANGE OVER THE KEWEENAW E THROUGH THE N TIER
COUNTIES...TO AS WARM AS 1.5-3C OVER MENOMINEE COUNTY /WARMEST OFF
THE GFS/.
FCST MODELS DO SHOW AN EMBEDDED SHORTWAVE/TROUGH SET UP ACROSS S
MANITOBA AT 00Z THURSDAY...BUT THE OVERALL STRENGTH IS DIFFERENT.
THE CONSENSUS IS THAT THIS FEATURE WILL GO ON ITS OWN...AND BEGIN TO
RETROGRADE...WITH RIDGING AT THE SFC AND ALOFT OVER THE UPPER GREAT
LAKES. ALTHOUGH THE MAIN SFC HIGH WILL SHIFT NE MORE INTO
QUEBEC...THE RIDGE WILL BE WELL ESTABLISHED OVERHEAD.
ONLY HAVE SLIGHT CHANCE POPS FOR THE KEWEENAW SUNDAY...AND MAINLY
JUST ALONG LAKE SUPERIOR SUNDAY NIGHT. THIS LOOKS REASONABLE...BUT
WILL NOT INCREASE THE POTENTIAL. MODELS ARE PRETTY CONSISTENT WITH
THE OVERALL PATTERN THROUGH WEDNESDAY EVENING. HOWEVER...THE GFS HAS
A DEEPER 500MB LOW OVER QUEBEC RETROGRADING AS CLOSE AS THE E HALF
OF QUEBEC BY 18Z SATURDAY. THE ECMWF IS NOT AS IMPRESSIVE AND IS
MORE FOCUSED ON THE S 500MB LOW SPINNING OVER THE SE STATES. WILL
KEEP A GENERAL BLEND UNTIL A MORE CONCRETE SOLUTION APPEARS. EITHER
WAY...COOL WEATHER AND A MAINLY N FLOW SHOULD REMAIN ACROSS UPPER
MI.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 201 PM EDT MON SEP 28 2015
A COLD FRONT OVER WRN UPPER MI WILL PASS THRU KSAW IN THE NEXT FEW
HRS. A SECONDARY COLD FRONT WILL THEN FOLLOW THIS EVENING AND
OVERNIGHT. -SHRA ASSOCIATED WITH THE FIRST COLD FRONT WILL AFFECT
KSAW FOR MUCH OF THE AFTN WITH MVFR CONDITIONS LIKELY PREVAILING FOR
THE NEXT FEW HRS. TO THE W...INCOMING DRIER AIR HAS ALREADY RESULTED
IN LOW CLOUDS CLEARING OUT AT KIWD/KCMX...AND VFR CONDITIONS WILL BE
THE RULE AT THOSE TERMINALS THIS AFTN. BEHIND THE SECOND COLD
FRONT...NW WINDS WILL INCREASE...ESPECIALLY AT KCMX WHERE WINDS WILL
LIKELY GUST TO AROUND 25KT. INCOMING CHILLY AIR MASS WILL BE VERY
DRY...SO NOT EXPECTING ANYTHING MORE THAN SCT LAKE EFFECT CLOUDS TO
DEVELOP LATE TONIGHT/TUE MORNING...ALLOWING VFR CONDITIONS TO
PREVAIL AT KIWD/KCMX/KSAW TONIGHT/TUE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 421 PM EDT MON SEP 28 2015
WITH ONE COLD FRONT EXITING LAKE SUPERIOR NOW...A SECOND COLD FRONT
WILL SWEEP ACROSS THE LAKE TONIGHT. PRES RISES ALONG WITH INCREASING
OVERWATER INSTABILITY AS COLDER AIR FLOWS INTO THE UPPER LAKES WILL
RESULT IN NW WINDS INCREASING TO 20-30KT TONIGHT AFTER THE SECOND
COLD FRONT PASSES. WHILE WINDS WILL REMAIN MOSTLY IN THE 20-30KT
RANGE OVER ERN LAKE SUPERIOR TUE...WINDS WILL DIMINISH OVER THE WRN
LAKE AS HIGH PRES APPROACHES. WINDS WILL THEN DIMINISH TO MOSTLY
UNDER 15KT W TO E TUE NIGHT/WED AS HIGH PRES SETTLES OVER THE UPPER
LAKES. AS THE HIGH DRIFTS TO THE ENE THRU THE END OF THE WEEK...IT
WILL EXTEND A RIDGE BACK TOWARD THE UPPER LAKES. SINCE IT LOOKS LIKE
THE RIDGE MAY BE SITUATED A LITTLE FARTHER N THAN PREVIOUSLY
EXPECTED...EASTERLY WINDS MAY BECOME BRISK INTO THE 15-25KT RANGE AT
TIMES DURING THE LATE WEEK PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING
FOR MIZ002-004-009-010-084.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
420 PM EDT MON SEP 28 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 419 AM EDT MON SEP 28 2015
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW ZONAL FLOW ALONG
THE CNDN BORDER AS RATHER SHEARED SHRTWV STRETCHING FM THE NRN
PLAINS INTO NW ONTARIO HAS WEAKENED THE UPR RDG THAT HAS BEEN SO
PERSISTENT RECENTLY OVER ERN NAMERICA. THIS SHRTWV IS SUPPORTING A
SFC COLD FNT THAT IS MOVING E THRU WRN LK SUP EARLY THIS MRNG. SINCE
THIS DISTURBANCE IS SHEARED OUT AND THE MSTR INFLOW IN THE SW FLOW
AHEAD OF THE FNT IS RATHER MODEST...SHOWER COVERAGE AHEAD OF THE
INCOMING FNT IS RATHER LIMITED...WITH SCT COVERAGE LIMITED BY THE
HIER STABILITY/DRY MID LVLS SHOWN ON THE 00Z MPX RAOB. CLDS IN
ADVANCE OF THE FNT ARE PUSHING THRU THE WRN CWA...BUT THERE IS AN
AXIS OF MOCLR SKIES OVER THE CENTRAL TO W OF SOME LO CLDS ACRS THE SE
HALF OF THE CWA ASSOCIATED WITH LLVL MSTR SHOWN ON THE 00Z GRB/APX
RAOBS. STEADY SW WINDS IN THE WARM SECTOR ARE KEEPING TEMPS WELL
ABOVE NORMAL NOT FAR FM 60 EVEN WHERE THE SKY IS MOCLR. LOOKING
FARTHER TO THE W...THE 00Z ABERDEEN SDAKOTA ROAB SHOWS A VERY DRY
AIRMASS IS UNDER SFC HI PRES RDG TRAILING THE SFC COLD FNT. BUT
FARTHER TO THE W...THERE IS AN AREA OF COLDER CLD TOPS/SHOWERS/EVEN
SOME LTG STRIKES MOVING THRU THE NRN PLAINS. MODELS SHOW AREA OF UPR
DVGC/MID LVL FGEN IN RRQ OF 100KT H3 JET MAX SUPPORTING THE NW
ONTARIO SHRTWV IS OVER THIS AREA OF COLDER CLD TOPS. ANOTHER SHRTWV
IS DIGGING THRU SCENTRAL CANADA AND DEEPENING AN UPR TROF THERE.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS ASSOCIATED WITH
COLD FNT THAT WL BE CROSSING UPR MI TODAY.
TODAY...LATEST SHORT TERM GUIDANCE IS IN GOOD AGREEMENT SHOWING SFC
COLD FNT CROSSING UPR MI TODAY AND REACHING LK MI ARND 21Z. SINCE
UPR DVGC/AXIS OF MID LVL FGEN SUPPORTING AREA OF DISTURBED WX IN THE
NRN PLAINS IS FCST TO MOVE OVER THE UPR LKS WHILE THE FNT IS
CROSSING THE CWA...MOST OF THE MODELS SHOW SHOWER COVERAGE EXPANDING
WITH TIME. SINCE THE DRY AIR SHOWN ON THE ABERDEEN RAOB AND TRAILING
THE FNT IS MOST LIKELY TO IMPACT THE WRN CWA BEFORE THE ARRIVAL...WL
FCST THE HIEST LIKELY POPS OVER THE SE HALF OF UPR MI THIS AFTN.
ALTHOUGH THERE HAVE BEEN SOME LTG STRIKES OBSVD UPSTREAM...MODEL
FCST MUCAPES NO HIER THAN ABOUT 100 J/KG OVER THE CWA SUPPORT
LEAVING TS OUT OF THE FCST FOR NOW. WITH EARLIER COLD FROPA OVER THE
W...TEMPS THERE WL BE MUCH LOWER THAN YDAY.
TNGT...MODELS DIFFER ON HOW QUICKLY THE SHOWERS EXIT THE SE CWA THIS
EVNG. THE 00Z NAM IS QUITE A BIT SLOWER THAN THE REST OF THE
GUIDANCE...BUT FAVOR THE FASTER DRYING TREND SHOWN BY THE MAJORITY
OF THE OTHER MODELS GIVEN DRYNESS OF THE TRAILING AIRMASS DEPICTED
ON THE 00Z ABERDEEN RAOB. THESE MODELS FAVOR SOME LINGERING HIER
LIKELY POPS EARLY IN THE EVNG OVER THE SE BEFORE VIGOROUS DRYING
BRINGS A CLRG TREND EVEN THOUGH ANOTHER COLD FNT ASSOCIATED WITH
SHRTWV NOW DIGGING THRU SCENTRAL CANADA IS PROGGED TO PASS OVERNGT.
H85 TEMPS DROPPING TO ARND 0C OVER THE KEWEENAW BY 12Z TUE WL RESULT
IN A MUCH COOLER OVERNGT WITH MIN TEMPS DIPPING TO ARND 40 AND
PERHAPS THE UPR 30S AT SOME OF THE HIER TERRAIN LOCATIONS. STRONG NW
FLOW OVER THE RELATIVELY WARM LK WATERS WL LIMIT THE TEMP DROP.
ALTHOUGH THE SFC-H85 DELTA T BTWN THE RELATIVELY WARM LK WATERS /MID
TO UPR 50S F/IS SUFFICIENT FOR LK CLDS/PCPN...THE INCOMING AIRMASS
WL BE TOO DRY AND THE LLVL FLOW TOO ACYC TO SUPPORT MORE THAN SCT
CLDS OVER THE HIER TERRAIN.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 415 PM EDT MON SEP 28 2015
HIGHS WILL MAINLY BE IN THE 50S FOR HIGHS THROUGH THE PERIOD...WHICH
WILL BE THE FIRST STRETCH OF BELOW NORMAL TEMPERATURES FOR QUITE A
WHILE /AT LEAST 10 DAYS/.
WE BEGIN AT 00Z WEDNESDAY WITH THE LARGE SFC HIGH ACROSS MUCH OF THE
UPPER GREAT LAKES...AND THE MAIN 500MB TROUGH EXTENDING FROM N
QUEBEC DOWN THROUGH LOWER MI AND THE MS DELTA. FOR UPPER MI
MAINLY ZONAL FLOW IS FIGURED ALOFT THROUGH 00Z THURSDAY.
DRY WEATHER WILL DOMINATE MUCH OF THIS PERIOD. THE MAIN WEATHER
THREAT WILL LIKELY BE THE COLD TUESDAY NIGHT INTO WEDNESDAY
MORNING...AND AGAIN WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING.
HAVE ISSUED A FREEZE WATCH FOR THE W HALF...MINUS THE KEWEENAW
PENINSULA. WIND CHILL ADVISORIES MAY BE POSTED FOR THE REST OF THE
CWA IF THE CURRENT FCST HOLDS TRUE. THIS WILL BE THANKS TO LOWS OF
27-35F...WITH THE LOWEST VALUES INLAND FROM LAKE SUPERIOR. STAY
TUNED AS WINDS WILL BE CALM...AND THE POTENTIAL EXISTS FOR TEMPS TO
FALL ANOTHER COUPLE OF DEGREES FROM THE CURRENT FCST. 850MB TEMPS
WILL E IN THE -1C RANGE OVER THE KEWEENAW E THROUGH THE N TIER
COUNTIES...TO AS WARM AS 1.5-3C OVER MENOMINEE COUNTY /WARMEST OFF
THE GFS/.
FCST MODELS DO SHOW AN EMBEDDED SHORTWAVE/TROUGH SET UP ACROSS S
MANITOBA AT 00Z THURSDAY...BUT THE OVERALL STRENGTH IS DIFFERENT.
THE CONSENSUS IS THAT THIS FEATURE WILL GO ON ITS OWN...AND BEGIN TO
RETROGRADE...WITH RIDGING AT THE SFC AND ALOFT OVER THE UPPER GREAT
LAKES. ALTHOUGH THE MAIN SFC HIGH WILL SHIFT NE MORE INTO
QUEBEC...THE RIDGE WILL BE WELL ESTABLISHED OVERHEAD.
ONLY HAVE SLIGHT CHANCE POPS FOR THE KEWEENAW SUNDAY...AND MAINLY
JUST ALONG LAKE SUPERIOR SUNDAY NIGHT. THIS LOOKS REASONABLE...BUT
WILL NOT INCREASE THE POTENTIAL. MODELS ARE PRETTY CONSISTENT WITH
THE OVERALL PATTERN THROUGH WEDNESDAY EVENING. HOWEVER...THE GFS HAS
A DEEPER 500MB LOW OVER QUEBEC RETROGRADING AS CLOSE AS THE E HALF
OF QUEBEC BY 18Z SATURDAY. THE ECMWF IS NOT AS IMPRESSIVE AND IS
MORE FOCUSED ON THE S 500MB LOW SPINNING OVER THE SE STATES. WILL
KEEP A GENERAL BLEND UNTIL A MORE CONCRETE SOLUTION APPEARS. EITHER
WAY...COOL WEATHER AND A MAINLY N FLOW SHOULD REMAIN ACROSS UPPER
MI.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 201 PM EDT MON SEP 28 2015
A COLD FRONT OVER WRN UPPER MI WILL PASS THRU KSAW IN THE NEXT FEW
HRS. A SECONDARY COLD FRONT WILL THEN FOLLOW THIS EVENING AND
OVERNIGHT. -SHRA ASSOCIATED WITH THE FIRST COLD FRONT WILL AFFECT
KSAW FOR MUCH OF THE AFTN WITH MVFR CONDITIONS LIKELY PREVAILING FOR
THE NEXT FEW HRS. TO THE W...INCOMING DRIER AIR HAS ALREADY RESULTED
IN LOW CLOUDS CLEARING OUT AT KIWD/KCMX...AND VFR CONDITIONS WILL BE
THE RULE AT THOSE TERMINALS THIS AFTN. BEHIND THE SECOND COLD
FRONT...NW WINDS WILL INCREASE...ESPECIALLY AT KCMX WHERE WINDS WILL
LIKELY GUST TO AROUND 25KT. INCOMING CHILLY AIR MASS WILL BE VERY
DRY...SO NOT EXPECTING ANYTHING MORE THAN SCT LAKE EFFECT CLOUDS TO
DEVELOP LATE TONIGHT/TUE MORNING...ALLOWING VFR CONDITIONS TO
PREVAIL AT KIWD/KCMX/KSAW TONIGHT/TUE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 419 AM EDT MON SEP 28 2015
SW WINDS UP TO 25 KTS THIS MRNG AHEAD OF A COLD FRONT MOVING THRU
WESTERN LAKE SUPERIOR EARLY THIS MORNING WILL SHIFT TO THE W-NW UP
TO 20 KTS FOLLOWING THE FRONTAL PASSAGE BY EARLY AFTERNOON OVER THE
FAR EAST. ANOTHER COLD FRONT WILL SWING ACROSS THE LAKE TONIGHT.
EXPECT NNW WINDS TO INCREASE UP TO 25-30 KTS IN ITS WAKE LATE
TONIGHT/TUE. AS A TRAILING HIGH PRESSURE CLOSES IN ON THE AREA ON
TUE NIGHT/WED...WINDS WILL DIMINISH TO UNDER 15-20 KTS. ONCE THE
HIGH SHIFTS INTO QUEBEC LATER IN THE WEEK...E WINDS UP TO 20 KTS
WILL DOMINATE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING
FOR MIZ002-004-009-010-084.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
320 PM EDT MON SEP 28 2015
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE
.SYNOPSIS...
ISSUED AT 320 PM EDT MON SEP 28 2015
A COLD FRONT WILL MOVE SOUTH THROUGH THE AREA OVERNIGHT...BRINGING
RAIN SHOWERS WITH IT. THIS WILL BE FOLLOWED BY DRY CONDITIONS AND A
GRADUAL COOLING TREND WITH HIGH TEMPERATURES STRUGGLING TO REACH 60
BY THE END OF THE WEEK.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 320 PM EDT MON SEP 28 2015
NO SIGNIFICANT CHANGES WERE MADE TO THE FORECAST. STILL EXPECT A
BAND OF PREDOMINANTLY RAIN SHOWERS TO MOVE THROUGH THE AREA
OVERNIGHT.
MAIN CHALLENGE IS THE CHARACTER OF PRECIPITATION MOVING THROUGH THE
FORECAST AREA OVERNIGHT. SIMULATED REFLECTIVITY FROM THE ESRL
EXPERIMENTAL HRRR SHOWS SUBSTANTIALLY LESS COVERAGE THAN THE
OPERATIONAL NCEP HRRR DOES. INCLUDED THUNDER FOR OUR NORTHEAST ZONES
AS SPC MESOANALYSIS CURRENTLY SHOWS A CORRIDOR OF MUCAPE GREATER
THAN 1000 J PER KG EXTENDING FROM NORTHERN LOWER MI INTO
SOUTHEASTERN LOWER MI. OVERALL THREAT FOR THUNDER WILL BE LOW AS THE
FRONT PASSES THROUGH THE AREA IN THE EARLY MORNING HOURS WELL AFTER
PEAK INSOLATION.
NO CONCERNS AFTER THIS FOR THE REST OF THE FORECAST PERIOD.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 320 PM EDT MON SEP 28 2015
DECIDED TO KEEP THE EXTENDED PERIOD DRY THOUGH THERE ARE SOME
CAVEATS TO THIS. FIRST...WITH SOMEWHAT MOIST H1000-H850 NE FLOW OFF
LAKE HURON THURSDAY THROUGH SATURDAY COMBINED WITH DECREASING H850
TEMPS...THERE COULD BE A FEW LAKE EFFECT SHOWERS MOVING TOWARD
CENTRAL LOWER MI DURING THIS TIME FRAME. MEDIUM RANGE GUIDANCE IS
NOT INDICATING ANY MEASURABLE PRECIP COMING OFF THE LAKE...BUT IT IS
SOMETHING WE WILL NEED TO FINE TUNE AS WE GET CLOSER.
SECOND...THE MODELS HAVE BEEN SENDING MIXED SIGNALS ON A TROPICAL
DISTURBANCE PRESENTLY IN THE GULF AS WELL AS TD 11 EAST OF FLORIDA.
LAST NIGHT`S GEM SOLUTION BROUGHT THE GULF SYSTEM RIGHT INTO
MICHIGAN THURSDAY AND FRIDAY...WHICH IS NOT ON THE 12Z RUN. THE
LATEST ECMWF BRINGS TD 11 NORTH AND THEN ABRUPTLY WEST INTO THE MID
ATLANTIC REGION BY THE WEEKEND...BRINGING A PRECIP SHIELD AS FAR
WEST AS LOWER MI BY SATURDAY. THIS IS A DEVIATION FROM THE PRIOR RUN
AS WELL AS OTHER MODEL RUNS. THERE IS NO CONFIDENCE IN ANY
SIGNIFICANT RAIN MAKING INTO OUR REGION AT THIS TIME...SO WILL KEEP
THINGS DRY.
THE GFS AND FIM ARE INDICATING SUSTAINED SFC WINDS OF 15-20 KTS
COMING OFF LAKE HURON THURSDAY AND FRIDAY...IMPACTING AREAS
ESPECIALLY EAST OF US 131. WITH H850 WINDS OF AROUND 25 KTS...THIS
SEEMS TO MAKE SENSE AS WE SHOULD BE MIXING TO AROUND THAT
HEIGHT...BUT PROBABLY NO FURTHER GIVEN THE CAA UNDERWAY.
HIGH TEMPERATURES MAY NOT MAKE 60 FOR MANY AREAS FRIDAY AND
SATURDAY...AND COMBINED WITH SOMEWHAT BREEZY CONDITIONS...IT WILL
CERTAINLY FEEL LIKE OCTOBER HAS ARRIVED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 139 PM EDT MON SEP 28 2015
IFR IS UNLIKELY THROUGH LATE EVENING OUTSIDE OF BRIEF POCKETS
OF SUB-1K FT CIGS NEAR MKG AND A LOW THREAT AT GRR. I DO NOT
EXPECT THIS TO BE SIGNIFICANT ENOUGH TO MENTION IN THE TAFS. MORE
IMPORTANTLY...A PERIOD OF IFR APPEARS LIKELY AS A COLD FRONT MOVES
INTO SOUTHERN LOWER MI EARLY TUESDAY MORNING. THIS WOULD MAINLY BE
FOR LOWER CIGS...THOUGH SOME LOWER VIS TO 2 MILES OR LESS IS
POSSIBLE. CURRENT OBSERVATIONS ALONG THE FRONT IN NORTHERN WI
SUPPORT THIS TREND. LIGHT RAIN IS EXPECTED THROUGH THE MORNING
PERIOD...WITH TSRA NOT LIKELY. WINDS BEHIND THE FRONT ARE EXPECTED
TO BE 10 KNOTS OR GREATER OUT OF THE N/NE.
&&
.MARINE...
ISSUED AT 320 PM EDT MON SEP 28 2015
LITTLE CHANGE TO THE PREVIOUS DISCUSSION. A SMALL CRAFT ADVISORY IS
IN EFFECT FOR INCREASING WINDS AND WAVES OVERNIGHT. ELEVATED WINDS
AND WAVES WILL PERSIST MOST OF TUESDAY. CONFIDENCE WITH RESPECT TO
WINDS...WAVES...AND TIMING IS MARGINALLY GOOD. LATEST WAVEWATCH 3
RUN IS PRETTY CONSISTENT WITH THE PREVIOUS RUN. AS NOTED BEFORE...
THE WHITEHALL TO GRAND HAVEN AREA MAY BE SHELTERED FROM THE LARGER
WAVES BY THE SABLE POINTS TO THE NORTH...SO HAVE LEFT THIS AREA OUT
OF THE ADVISORY FOR NOW. THIS ADMITTEDLY MAY BE A BIT TOO PRECISE
THIS FAR OUT...SO THIS AREA COULD GET ADDED TO THE ADVISORY WITH
FUTURE UPDATES.
A LIKELY SCENARIO IS THAT HIGHER WAVES WILL PERSIST CONSIDERABLY
LONGER SOUTH OF SOUTH HAVEN WITH THE FAVORABLE FETCH...ALLOWING
POINTS FARTHER NORTH TO SEE AN EARLIER CANCELLATION. 3 TO 5 FOOT
WAVES COULD END UP PERSISTING WELL INTO WEDNESDAY MORNING AROUND
SOUTH HAVEN AND POINTS FARTHER SOUTH...WHICH WOULD REQUIRE AN
EXTENSION IN TIME OF THIS ADVISORY.
&&
.HYDROLOGY...
ISSUED AT 1223 PM EDT MON SEP 28 2015
CURRENT STREAMFLOW AND SOIL MOISTURE ACROSS SOUTHWEST LOWER MICHIGAN
ARE BOTH RUNNING NEAR NORMAL. NO SIGNIFICANT CHANGES ARE FORECAST...
AS LESS THAN A HALF INCH OF RAIN IS EXPECTED THROUGH THE WEEK.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY FROM 8 AM TUESDAY TO 2 AM EDT WEDNESDAY FOR
LMZ844>846-848-849.
&&
$$
SYNOPSIS...TJT
SHORT TERM...TJT
LONG TERM...HOVING
AVIATION...HOVING
HYDROLOGY...63
MARINE...TJT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
201 PM EDT MON SEP 28 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 419 AM EDT MON SEP 28 2015
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW ZONAL FLOW ALONG
THE CNDN BORDER AS RATHER SHEARED SHRTWV STRETCHING FM THE NRN
PLAINS INTO NW ONTARIO HAS WEAKENED THE UPR RDG THAT HAS BEEN SO
PERSISTENT RECENTLY OVER ERN NAMERICA. THIS SHRTWV IS SUPPORTING A
SFC COLD FNT THAT IS MOVING E THRU WRN LK SUP EARLY THIS MRNG. SINCE
THIS DISTURBANCE IS SHEARED OUT AND THE MSTR INFLOW IN THE SW FLOW
AHEAD OF THE FNT IS RATHER MODEST...SHOWER COVERAGE AHEAD OF THE
INCOMING FNT IS RATHER LIMITED...WITH SCT COVERAGE LIMITED BY THE
HIER STABILITY/DRY MID LVLS SHOWN ON THE 00Z MPX RAOB. CLDS IN
ADVANCE OF THE FNT ARE PUSHING THRU THE WRN CWA...BUT THERE IS AN
AXIS OF MOCLR SKIES OVER THE CENTRAL TO W OF SOME LO CLDS ACRS THE SE
HALF OF THE CWA ASSOCIATED WITH LLVL MSTR SHOWN ON THE 00Z GRB/APX
RAOBS. STEADY SW WINDS IN THE WARM SECTOR ARE KEEPING TEMPS WELL
ABOVE NORMAL NOT FAR FM 60 EVEN WHERE THE SKY IS MOCLR. LOOKING
FARTHER TO THE W...THE 00Z ABERDEEN SDAKOTA ROAB SHOWS A VERY DRY
AIRMASS IS UNDER SFC HI PRES RDG TRAILING THE SFC COLD FNT. BUT
FARTHER TO THE W...THERE IS AN AREA OF COLDER CLD TOPS/SHOWERS/EVEN
SOME LTG STRIKES MOVING THRU THE NRN PLAINS. MODELS SHOW AREA OF UPR
DVGC/MID LVL FGEN IN RRQ OF 100KT H3 JET MAX SUPPORTING THE NW
ONTARIO SHRTWV IS OVER THIS AREA OF COLDER CLD TOPS. ANOTHER SHRTWV
IS DIGGING THRU SCENTRAL CANADA AND DEEPENING AN UPR TROF THERE.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS ASSOCIATED WITH
COLD FNT THAT WL BE CROSSING UPR MI TODAY.
TODAY...LATEST SHORT TERM GUIDANCE IS IN GOOD AGREEMENT SHOWING SFC
COLD FNT CROSSING UPR MI TODAY AND REACHING LK MI ARND 21Z. SINCE
UPR DVGC/AXIS OF MID LVL FGEN SUPPORTING AREA OF DISTURBED WX IN THE
NRN PLAINS IS FCST TO MOVE OVER THE UPR LKS WHILE THE FNT IS
CROSSING THE CWA...MOST OF THE MODELS SHOW SHOWER COVERAGE EXPANDING
WITH TIME. SINCE THE DRY AIR SHOWN ON THE ABERDEEN RAOB AND TRAILING
THE FNT IS MOST LIKELY TO IMPACT THE WRN CWA BEFORE THE ARRIVAL...WL
FCST THE HIEST LIKELY POPS OVER THE SE HALF OF UPR MI THIS AFTN.
ALTHOUGH THERE HAVE BEEN SOME LTG STRIKES OBSVD UPSTREAM...MODEL
FCST MUCAPES NO HIER THAN ABOUT 100 J/KG OVER THE CWA SUPPORT
LEAVING TS OUT OF THE FCST FOR NOW. WITH EARLIER COLD FROPA OVER THE
W...TEMPS THERE WL BE MUCH LOWER THAN YDAY.
TNGT...MODELS DIFFER ON HOW QUICKLY THE SHOWERS EXIT THE SE CWA THIS
EVNG. THE 00Z NAM IS QUITE A BIT SLOWER THAN THE REST OF THE
GUIDANCE...BUT FAVOR THE FASTER DRYING TREND SHOWN BY THE MAJORITY
OF THE OTHER MODELS GIVEN DRYNESS OF THE TRAILING AIRMASS DEPICTED
ON THE 00Z ABERDEEN RAOB. THESE MODELS FAVOR SOME LINGERING HIER
LIKELY POPS EARLY IN THE EVNG OVER THE SE BEFORE VIGOROUS DRYING
BRINGS A CLRG TREND EVEN THOUGH ANOTHER COLD FNT ASSOCIATED WITH
SHRTWV NOW DIGGING THRU SCENTRAL CANADA IS PROGGED TO PASS OVERNGT.
H85 TEMPS DROPPING TO ARND 0C OVER THE KEWEENAW BY 12Z TUE WL RESULT
IN A MUCH COOLER OVERNGT WITH MIN TEMPS DIPPING TO ARND 40 AND
PERHAPS THE UPR 30S AT SOME OF THE HIER TERRAIN LOCATIONS. STRONG NW
FLOW OVER THE RELATIVELY WARM LK WATERS WL LIMIT THE TEMP DROP.
ALTHOUGH THE SFC-H85 DELTA T BTWN THE RELATIVELY WARM LK WATERS /MID
TO UPR 50S F/IS SUFFICIENT FOR LK CLDS/PCPN...THE INCOMING AIRMASS
WL BE TOO DRY AND THE LLVL FLOW TOO ACYC TO SUPPORT MORE THAN SCT
CLDS OVER THE HIER TERRAIN.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 409 AM EDT MON SEP 28 2015
UPPER LEVEL TROUGH FROM HUDSON BAY TO UPPER GREAT LAKES SLIDES TO
EASTERN CANADA LATE THIS WEEK WHILE HEIGHTS SLOWLY REBOUND FM
NORTHERN PLAINS TO UPPER GREAT LAKES. TROUGH WILL ENSURE A COOLER
WEEK WITH FROST/FREEZE OVER PARTS OF CWA TUE NIGHT AND MAYBE WED
NIGHT AS WELL.
ON TUESDAY...COOLER AIR ARRIVES WITH H85 TEMPS DOWN TO 0C TO -1C BY
AFTN. NORTHWEST WINDS COULD BE GUSTY UP TO 25 MPH...ESPECIALLY
CLOSER TO LK SUPERIOR. THOUGH APPROACHING HIGH IS THE DOMINANT
FACTOR...NAM/GFS/GEM-REGIONAL INDICATE HIGHER H85 RH MOVING ACROSS
LK SUPERIOR BY 12Z AND EXPANDING BY 18Z AS THE COOLER AIR ARRIVES.
ENVISION FEW-SCT STRATOCU CLOUDS EXPANDING INTO A STRATOCU/CUMULUS
DECK MAINLY CNTRL CWA BY AFTN...THEN DIMINISHING THROUGH THE REST OF
AFTN. WITH THE CLOUDS AND COLD AIR ADVECTION...TEMPS WILL ONLY REACH
LOW TO MID 50S NEAR LK SUPERIOR AND MAY TOUCH 60 DEGREES IN THE FAR
SCNTRL. EVEN THOUGH SWIM RISK WILL BE HIGH ALONG MARQUETTE AND ALGER
COUNTIES...AIR TEMPERATURES BELOW 55 DEGREES WILL PROHIBIT THE
ISSUANCE OF A BEACH HAZARDS STATEMENT.
NEXT UP IS TUE NIGHT AND THE FROST/FREEZE POTENTIAL. UPSHOT IS THE
FROST/FREEZE POTENTIAL...AT LEAST AWAY FM THE INTERIOR WEST...IS NOT
AS CLEAR CUT AS IT LOOKED THE LAST FEW DAYS. RECENTLY IN THE
MODELS...IT APPEARED THAT THE APPROACHING HIGH WOULD SETTLE RIGHT
OVERHEAD TUESDAY NIGHT. NOW...RIDGE AXIS STAYS MAINLY OVER WESTERN
UPR MICHIGAN WHILE A LIGHT BUT PERSISTENT NE LOW-LEVEL FLOW AFFECTS
EAST HALF OF CWA /SEE THIS AS 950-900MB WINDS OVER 10 KTS FM NCNTRL
INTO EASTERN CWA. ALSO...WITH H85 TEMPS STAYING AROUND -1C OVERNIGHT
TUESDAY NIGHT AND MORE OF AN ONSHORE WIND WITH SOME 875MB-850MB
MOISTURE SHOWN ON GFS/NAM SOUNDINGS...MAY HAVE TO CONTEND WITH SCT-
BKN LAKE EFFECT CLOUDS AS DELTA T VALUES WILL BE OVER 15C. BEST
CHANCE FOR BKN CLOUDS WOULD BE OVER FAR NCNTRL UPR MICHIGAN AND
ACROSS THE KEWEENAW. ADJUSTED SKY GRIDS TO BUMP UP CLOUD COVER FOR
THERE AREAS...ESPECIALLY FOR THE KEWEENAW. FOR TEMPS...USED GUIDANCE
THAT SHOWED LOWEST TEMPS IN THE UPR 20S OVER INTERIOR WEST BUT KEPT
READINGS MAINLY MID-UPR 30S WHERE CLOUDS MAY DISRUPT COOLING.
AFTER A MOSTLY SUNNY BUT COOL DAY ON WED...ANOTHER CHILLY NIGHT WITH
SOME FROST SEEMS PROBABLE FOR WED NIGHT. SETUP IS NO BETTER THAN TUE
NIGHT THOUGH AS HIGH CENTER IS MORE OVER QUEBEC AND THAT LEAVES A
LIGHT EASTERLY FLOW ACROSS UPR MICHIGAN. EVEN SO...MIN TEMPS MAY BE
AT LEAST IN LOWER 30S...ESPECIALLY OVER INLAND AREAS. DAYTIME HIGHS
WED INTO THU SHOULD STAY IN THE 50S TO AROUND 60 DEGREES. THESE
VALUES ARE PRETTY SEASONABLE FOR LATE SEPTEMBER...THOUGH MUCH COOLER
THAN THE WELL ABOVE NORMAL TEMPS SEEN MUCH OF THIS MONTH.
AFTER SOME RAIN TODAY...DRIER TREND THAT BEGAN TO SHOW UP IN THE
MODELS LAST COUPLE DAYS CONTINUES AS HIGH PRESSURE BUILDING IN
BEHIND COLD FRONTAL PASSAGE TODAY EXPANDS ACROSS THE UPPER GREAT
LAKES ON WED AND BUILDS FURTHER TO OVER 1040MB IN QUEBEC ON FRIDAY.
RIDGE FM THE HIGH EXPANDS WESTWARD ACROSS THE UPPER GREAT LAKES AND
AS FAR WEST AS SASKATCHEWAN AND MANITOBA. AT FIRST GLANCE...THIS
SHOULD KEEP MAJORITY OF REGION DRY THROUGH THE UPCOMING WEEKEND.
HOWEVER...GFS AND 12Z ECMWF INDICATE THAT DECENT STRENGTH SHORTWAVE
TROUGH BREAKING FREE FM THE LARGER SCALE TROUGH OVER EASTERN CANADA
WILL SLIDE OVER UPR GREAT LAKES FRIDAY INTO THE WEEKEND. 00Z ECMWF
NOT NEAR AS DEEP WITH TROUGH AS IT SHOWED WITH 12Z RUN THOUGH. DEEP
MOISTURE APPEARS SPOTTY BUT THERE ARE HINTS THERE MAY BE ENOUGH
FORCING AND MOISTURE TO SUPPORT SOME SHOWERS. OVERALL MOST CWA WILL
REMAIN DRY THROUGH NEXT WEEKEND AS UPPER LEVEL TROUGH WILL BE
LACKING LOW-LEVEL SUPPORT AS THE SFC HIGH REMAINS THE DOMINANT
WEATHER FEATURE. IF THERE ENDS UP BEING BETTER CYCLONIC FLOW IN LOW-
LEVELS AS 12Z ECMWF INDICATED...COULD SEE HELP FM LK SUPERIOR FOR
PRECIP AS H85 TEMPS ARE FORECAST TO BE AS LOW AS -3C WITH THE UPPER
TROUGH OVERHEAD. DAYTIME HIGHS SHOULD SETTLE BACK INTO THE 50S
FRIDAY AND SATURDAY WITH THE COOLER TEMPS ALOFT.
FINALLY...GFS IS MUCH MORE AGGRESSIVE THAN ECMWF WITH SECONDARY
STRONGER SHORTWAVE TROUGH MOVING THROUGH IN MORE TYPICAL NW TO SE
PROGRESSION LATE NEXT WEEKEND INTO EARLY NEXT WEEK /DAYS 8-10/. H85
TEMPS AS LOW AS -9C IN THE CORE OF THE COLDEST AIR OVER ONTARIO WITH
AROUND -5C OVER UPR MICHIGAN LAST TWO RUNS. NEITHER THE 12Z RUN OR
MOST RECENT 00Z RUN OF ECMWF SHOWED ADDITIONAL TROUGHING THOUGH WITH
RIDGING RE APPEARING INTO NEXT WEEK IN WAKE OF THE WEEKEND
TROUGHING. ECMWF DOES INDICATE TROUGHING AND SIMILAR DEGREE OF COLD
AIR...BUT IT STAYS WELL UPSTREAM OVER NORTHWEST CANADA MOST OF THE
WEEK. FOR THE FORECAST...CONSENSUS SHOULD COVER IT ATTM. USUALLY DO
NOT GET TOO CONCERNED WITH THESE TYPE OF DETAILS IN THE FAR REACHES
OF EXTENDED AND BEYOND...BUT GIVEN THE VERY WARM SEPTEMBER ABOUT TO
CONCLUDE /POTENTIALLY RECORD WARMEST AT SOME LOCATIONS ACROSS UPR
MICHIGAN/...IT IS NOTABLE THAT SOME MODELS ARE HINTING AT COOLER
AIRMASSES CLOSE BY AS FIRST FULL WEEK OF OCTOBER ARRIVES. OFFICIAL
8-14 DAY AND EXPERIMENTAL 3-4 WEEK FORECASTS FM CPC STILL INDICATING
WARMER THAN NORMAL TEMPERATURES SHOULD PREVAIL OVERALL THROUGH MUCH
OF NEXT MONTH.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 201 PM EDT MON SEP 28 2015
A COLD FRONT OVER WRN UPPER MI WILL PASS THRU KSAW IN THE NEXT FEW
HRS. A SECONDARY COLD FRONT WILL THEN FOLLOW THIS EVENING AND
OVERNIGHT. -SHRA ASSOCIATED WITH THE FIRST COLD FRONT WILL AFFECT
KSAW FOR MUCH OF THE AFTN WITH MVFR CONDITIONS LIKELY PREVAILING FOR
THE NEXT FEW HRS. TO THE W...INCOMING DRIER AIR HAS ALREADY RESULTED
IN LOW CLOUDS CLEARING OUT AT KIWD/KCMX...AND VFR CONDITIONS WILL BE
THE RULE AT THOSE TERMINALS THIS AFTN. BEHIND THE SECOND COLD
FRONT...NW WINDS WILL INCREASE...ESPECIALLY AT KCMX WHERE WINDS WILL
LIKELY GUST TO AROUND 25KT. INCOMING CHILLY AIR MASS WILL BE VERY
DRY...SO NOT EXPECTING ANYTHING MORE THAN SCT LAKE EFFECT CLOUDS TO
DEVELOP LATE TONIGHT/TUE MORNING...ALLOWING VFR CONDITIONS TO
PREVAIL AT KIWD/KCMX/KSAW TONIGHT/TUE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 419 AM EDT MON SEP 28 2015
SW WINDS UP TO 25 KTS THIS MRNG AHEAD OF A COLD FRONT MOVING THRU
WESTERN LAKE SUPERIOR EARLY THIS MORNING WILL SHIFT TO THE W-NW UP
TO 20 KTS FOLLOWING THE FRONTAL PASSAGE BY EARLY AFTERNOON OVER THE
FAR EAST. ANOTHER COLD FRONT WILL SWING ACROSS THE LAKE TONIGHT.
EXPECT NNW WINDS TO INCREASE UP TO 25-30 KTS IN ITS WAKE LATE
TONIGHT/TUE. AS A TRAILING HIGH PRESSURE CLOSES IN ON THE AREA ON
TUE NIGHT/WED...WINDS WILL DIMINISH TO UNDER 15-20 KTS. ONCE THE
HIGH SHIFTS INTO QUEBEC LATER IN THE WEEK...E WINDS UP TO 20 KTS
WILL DOMINATE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
731 AM EDT MON SEP 28 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 419 AM EDT MON SEP 28 2015
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW ZONAL FLOW ALONG
THE CNDN BORDER AS RATHER SHEARED SHRTWV STRETCHING FM THE NRN
PLAINS INTO NW ONTARIO HAS WEAKENED THE UPR RDG THAT HAS BEEN SO
PERSISTENT RECENTLY OVER ERN NAMERICA. THIS SHRTWV IS SUPPORTING A
SFC COLD FNT THAT IS MOVING E THRU WRN LK SUP EARLY THIS MRNG. SINCE
THIS DISTURBANCE IS SHEARED OUT AND THE MSTR INFLOW IN THE SW FLOW
AHEAD OF THE FNT IS RATHER MODEST...SHOWER COVERAGE AHEAD OF THE
INCOMING FNT IS RATHER LIMITED...WITH SCT COVERAGE LIMITED BY THE
HIER STABILITY/DRY MID LVLS SHOWN ON THE 00Z MPX RAOB. CLDS IN
ADVANCE OF THE FNT ARE PUSHING THRU THE WRN CWA...BUT THERE IS AN
AXIS OF MOCLR SKIES OVER THE CENTRAL TO W OF SOME LO CLDS ACRS THE SE
HALF OF THE CWA ASSOCIATED WITH LLVL MSTR SHOWN ON THE 00Z GRB/APX
RAOBS. STEADY SW WINDS IN THE WARM SECTOR ARE KEEPING TEMPS WELL
ABOVE NORMAL NOT FAR FM 60 EVEN WHERE THE SKY IS MOCLR. LOOKING
FARTHER TO THE W...THE 00Z ABERDEEN SDAKOTA ROAB SHOWS A VERY DRY
AIRMASS IS UNDER SFC HI PRES RDG TRAILING THE SFC COLD FNT. BUT
FARTHER TO THE W...THERE IS AN AREA OF COLDER CLD TOPS/SHOWERS/EVEN
SOME LTG STRIKES MOVING THRU THE NRN PLAINS. MODELS SHOW AREA OF UPR
DVGC/MID LVL FGEN IN RRQ OF 100KT H3 JET MAX SUPPORTING THE NW
ONTARIO SHRTWV IS OVER THIS AREA OF COLDER CLD TOPS. ANOTHER SHRTWV
IS DIGGING THRU SCENTRAL CANADA AND DEEPENING AN UPR TROF THERE.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS ASSOCIATED WITH
COLD FNT THAT WL BE CROSSING UPR MI TODAY.
TODAY...LATEST SHORT TERM GUIDANCE IS IN GOOD AGREEMENT SHOWING SFC
COLD FNT CROSSING UPR MI TODAY AND REACHING LK MI ARND 21Z. SINCE
UPR DVGC/AXIS OF MID LVL FGEN SUPPORTING AREA OF DISTURBED WX IN THE
NRN PLAINS IS FCST TO MOVE OVER THE UPR LKS WHILE THE FNT IS
CROSSING THE CWA...MOST OF THE MODELS SHOW SHOWER COVERAGE EXPANDING
WITH TIME. SINCE THE DRY AIR SHOWN ON THE ABERDEEN RAOB AND TRAILING
THE FNT IS MOST LIKELY TO IMPACT THE WRN CWA BEFORE THE ARRIVAL...WL
FCST THE HIEST LIKELY POPS OVER THE SE HALF OF UPR MI THIS AFTN.
ALTHOUGH THERE HAVE BEEN SOME LTG STRIKES OBSVD UPSTREAM...MODEL
FCST MUCAPES NO HIER THAN ABOUT 100 J/KG OVER THE CWA SUPPORT
LEAVING TS OUT OF THE FCST FOR NOW. WITH EARLIER COLD FROPA OVER THE
W...TEMPS THERE WL BE MUCH LOWER THAN YDAY.
TNGT...MODELS DIFFER ON HOW QUICKLY THE SHOWERS EXIT THE SE CWA THIS
EVNG. THE 00Z NAM IS QUITE A BIT SLOWER THAN THE REST OF THE
GUIDANCE...BUT FAVOR THE FASTER DRYING TREND SHOWN BY THE MAJORITY
OF THE OTHER MODELS GIVEN DRYNESS OF THE TRAILING AIRMASS DEPICTED
ON THE 00Z ABERDEEN RAOB. THESE MODELS FAVOR SOME LINGERING HIER
LIKELY POPS EARLY IN THE EVNG OVER THE SE BEFORE VIGOROUS DRYING
BRINGS A CLRG TREND EVEN THOUGH ANOTHER COLD FNT ASSOCIATED WITH
SHRTWV NOW DIGGING THRU SCENTRAL CANADA IS PROGGED TO PASS OVERNGT.
H85 TEMPS DROPPING TO ARND 0C OVER THE KEWEENAW BY 12Z TUE WL RESULT
IN A MUCH COOLER OVERNGT WITH MIN TEMPS DIPPING TO ARND 40 AND
PERHAPS THE UPR 30S AT SOME OF THE HIER TERRAIN LOCATIONS. STRONG NW
FLOW OVER THE RELATIVELY WARM LK WATERS WL LIMIT THE TEMP DROP.
ALTHOUGH THE SFC-H85 DELTA T BTWN THE RELATIVELY WARM LK WATERS /MID
TO UPR 50S F/IS SUFFICIENT FOR LK CLDS/PCPN...THE INCOMING AIRMASS
WL BE TOO DRY AND THE LLVL FLOW TOO ACYC TO SUPPORT MORE THAN SCT
CLDS OVER THE HIER TERRAIN.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 409 AM EDT MON SEP 28 2015
UPPER LEVEL TROUGH FROM HUDSON BAY TO UPPER GREAT LAKES SLIDES TO
EASTERN CANADA LATE THIS WEEK WHILE HEIGHTS SLOWLY REBOUND FM
NORTHERN PLAINS TO UPPER GREAT LAKES. TROUGH WILL ENSURE A COOLER
WEEK WITH FROST/FREEZE OVER PARTS OF CWA TUE NIGHT AND MAYBE WED
NIGHT AS WELL.
ON TUESDAY...COOLER AIR ARRIVES WITH H85 TEMPS DOWN TO 0C TO -1C BY
AFTN. NORTHWEST WINDS COULD BE GUSTY UP TO 25 MPH...ESPECIALLY
CLOSER TO LK SUPERIOR. THOUGH APPROACHING HIGH IS THE DOMINANT
FACTOR...NAM/GFS/GEM-REGIONAL INDICATE HIGHER H85 RH MOVING ACROSS
LK SUPERIOR BY 12Z AND EXPANDING BY 18Z AS THE COOLER AIR ARRIVES.
ENVISION FEW-SCT STRATOCU CLOUDS EXPANDING INTO A STRATOCU/CUMULUS
DECK MAINLY CNTRL CWA BY AFTN...THEN DIMINISHING THROUGH THE REST OF
AFTN. WITH THE CLOUDS AND COLD AIR ADVECTION...TEMPS WILL ONLY REACH
LOW TO MID 50S NEAR LK SUPERIOR AND MAY TOUCH 60 DEGREES IN THE FAR
SCNTRL. EVEN THOUGH SWIM RISK WILL BE HIGH ALONG MARQUETTE AND ALGER
COUNTIES...AIR TEMPERATURES BELOW 55 DEGREES WILL PROHIBIT THE
ISSUANCE OF A BEACH HAZARDS STATEMENT.
NEXT UP IS TUE NIGHT AND THE FROST/FREEZE POTENTIAL. UPSHOT IS THE
FROST/FREEZE POTENTIAL...AT LEAST AWAY FM THE INTERIOR WEST...IS NOT
AS CLEAR CUT AS IT LOOKED THE LAST FEW DAYS. RECENTLY IN THE
MODELS...IT APPEARED THAT THE APPROACHING HIGH WOULD SETTLE RIGHT
OVERHEAD TUESDAY NIGHT. NOW...RIDGE AXIS STAYS MAINLY OVER WESTERN
UPR MICHIGAN WHILE A LIGHT BUT PERSISTENT NE LOW-LEVEL FLOW AFFECTS
EAST HALF OF CWA /SEE THIS AS 950-900MB WINDS OVER 10 KTS FM NCNTRL
INTO EASTERN CWA. ALSO...WITH H85 TEMPS STAYING AROUND -1C OVERNIGHT
TUESDAY NIGHT AND MORE OF AN ONSHORE WIND WITH SOME 875MB-850MB
MOISTURE SHOWN ON GFS/NAM SOUNDINGS...MAY HAVE TO CONTEND WITH SCT-
BKN LAKE EFFECT CLOUDS AS DELTA T VALUES WILL BE OVER 15C. BEST
CHANCE FOR BKN CLOUDS WOULD BE OVER FAR NCNTRL UPR MICHIGAN AND
ACROSS THE KEWEENAW. ADJUSTED SKY GRIDS TO BUMP UP CLOUD COVER FOR
THERE AREAS...ESPECIALLY FOR THE KEWEENAW. FOR TEMPS...USED GUIDANCE
THAT SHOWED LOWEST TEMPS IN THE UPR 20S OVER INTERIOR WEST BUT KEPT
READINGS MAINLY MID-UPR 30S WHERE CLOUDS MAY DISRUPT COOLING.
AFTER A MOSTLY SUNNY BUT COOL DAY ON WED...ANOTHER CHILLY NIGHT WITH
SOME FROST SEEMS PROBABLE FOR WED NIGHT. SETUP IS NO BETTER THAN TUE
NIGHT THOUGH AS HIGH CENTER IS MORE OVER QUEBEC AND THAT LEAVES A
LIGHT EASTERLY FLOW ACROSS UPR MICHIGAN. EVEN SO...MIN TEMPS MAY BE
AT LEAST IN LOWER 30S...ESPECIALLY OVER INLAND AREAS. DAYTIME HIGHS
WED INTO THU SHOULD STAY IN THE 50S TO AROUND 60 DEGREES. THESE
VALUES ARE PRETTY SEASONABLE FOR LATE SEPTEMBER...THOUGH MUCH COOLER
THAN THE WELL ABOVE NORMAL TEMPS SEEN MUCH OF THIS MONTH.
AFTER SOME RAIN TODAY...DRIER TREND THAT BEGAN TO SHOW UP IN THE
MODELS LAST COUPLE DAYS CONTINUES AS HIGH PRESSURE BUILDING IN
BEHIND COLD FRONTAL PASSAGE TODAY EXPANDS ACROSS THE UPPER GREAT
LAKES ON WED AND BUILDS FURTHER TO OVER 1040MB IN QUEBEC ON FRIDAY.
RIDGE FM THE HIGH EXPANDS WESTWARD ACROSS THE UPPER GREAT LAKES AND
AS FAR WEST AS SASKATCHEWAN AND MANITOBA. AT FIRST GLANCE...THIS
SHOULD KEEP MAJORITY OF REGION DRY THROUGH THE UPCOMING WEEKEND.
HOWEVER...GFS AND 12Z ECMWF INDICATE THAT DECENT STRENGTH SHORTWAVE
TROUGH BREAKING FREE FM THE LARGER SCALE TROUGH OVER EASTERN CANADA
WILL SLIDE OVER UPR GREAT LAKES FRIDAY INTO THE WEEKEND. 00Z ECMWF
NOT NEAR AS DEEP WITH TROUGH AS IT SHOWED WITH 12Z RUN THOUGH. DEEP
MOISTURE APPEARS SPOTTY BUT THERE ARE HINTS THERE MAY BE ENOUGH
FORCING AND MOISTURE TO SUPPORT SOME SHOWERS. OVERALL MOST CWA WILL
REMAIN DRY THROUGH NEXT WEEKEND AS UPPER LEVEL TROUGH WILL BE
LACKING LOW-LEVEL SUPPORT AS THE SFC HIGH REMAINS THE DOMINANT
WEATHER FEATURE. IF THERE ENDS UP BEING BETTER CYCLONIC FLOW IN LOW-
LEVELS AS 12Z ECMWF INDICATED...COULD SEE HELP FM LK SUPERIOR FOR
PRECIP AS H85 TEMPS ARE FORECAST TO BE AS LOW AS -3C WITH THE UPPER
TROUGH OVERHEAD. DAYTIME HIGHS SHOULD SETTLE BACK INTO THE 50S
FRIDAY AND SATURDAY WITH THE COOLER TEMPS ALOFT.
FINALLY...GFS IS MUCH MORE AGGRESSIVE THAN ECMWF WITH SECONDARY
STRONGER SHORTWAVE TROUGH MOVING THROUGH IN MORE TYPICAL NW TO SE
PROGRESSION LATE NEXT WEEKEND INTO EARLY NEXT WEEK /DAYS 8-10/. H85
TEMPS AS LOW AS -9C IN THE CORE OF THE COLDEST AIR OVER ONTARIO WITH
AROUND -5C OVER UPR MICHIGAN LAST TWO RUNS. NEITHER THE 12Z RUN OR
MOST RECENT 00Z RUN OF ECMWF SHOWED ADDITIONAL TROUGHING THOUGH WITH
RIDGING RE APPEARING INTO NEXT WEEK IN WAKE OF THE WEEKEND
TROUGHING. ECMWF DOES INDICATE TROUGHING AND SIMILAR DEGREE OF COLD
AIR...BUT IT STAYS WELL UPSTREAM OVER NORTHWEST CANADA MOST OF THE
WEEK. FOR THE FORECAST...CONSENSUS SHOULD COVER IT ATTM. USUALLY DO
NOT GET TOO CONCERNED WITH THESE TYPE OF DETAILS IN THE FAR REACHES
OF EXTENDED AND BEYOND...BUT GIVEN THE VERY WARM SEPTEMBER ABOUT TO
CONCLUDE /POTENTIALLY RECORD WARMEST AT SOME LOCATIONS ACROSS UPR
MICHIGAN/...IT IS NOTABLE THAT SOME MODELS ARE HINTING AT COOLER
AIRMASSES CLOSE BY AS FIRST FULL WEEK OF OCTOBER ARRIVES. OFFICIAL
8-14 DAY AND EXPERIMENTAL 3-4 WEEK FORECASTS FM CPC STILL INDICATING
WARMER THAN NORMAL TEMPERATURES SHOULD PREVAIL OVERALL THROUGH MUCH
OF NEXT MONTH.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 731 AM EDT MON SEP 28 2015
A COLD FNT THAT IS APRCHG CMX AND IWD WL PRESS SEWD AND BY SAW BY
NOON. SOME -SHRA ASSOCIATED WITH A WAVE OF LO PRES RUNNING ALONG
THIS BNDRY WL IMPACT SAW AND PERHAPS IWD...WITH SOME MVFR CONDITIONS
PSBL AT THOSE SITES WHEN THE -SHRA ARE MOST LIKELY AT THOSE PLACES
FM LATE THIS MRNG INTO THE AFTN. CMX IS MOST LIKELY TO MISS THIS
PCPN AND REMAIN VFR. THE ARRIVAL OF DRIER AIR IN THE AFTN WL BRING A
RETURN TO VFR CONDITIONS AT IWD AND THEN SAW. ALTHOUGH ANOTHER COLD
FNT WL SWING THRU TNGT WITH A STRONGER NNW WIND IN ITS WAKE...THE
AIRMASS WL BE TOO DRY FOR MORE THAN A FEW CLDS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 419 AM EDT MON SEP 28 2015
SW WINDS UP TO 25 KTS THIS MRNG AHEAD OF A COLD FRONT MOVING THRU
WESTERN LAKE SUPERIOR EARLY THIS MORNING WILL SHIFT TO THE W-NW UP
TO 20 KTS FOLLOWING THE FRONTAL PASSAGE BY EARLY AFTERNOON OVER THE
FAR EAST. ANOTHER COLD FRONT WILL SWING ACROSS THE LAKE TONIGHT.
EXPECT NNW WINDS TO INCREASE UP TO 25-30 KTS IN ITS WAKE LATE
TONIGHT/TUE. AS A TRAILING HIGH PRESSURE CLOSES IN ON THE AREA ON
TUE NIGHT/WED...WINDS WILL DIMINISH TO UNDER 15-20 KTS. ONCE THE
HIGH SHIFTS INTO QUEBEC LATER IN THE WEEK...E WINDS UP TO 20 KTS
WILL DOMINATE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
420 AM EDT MON SEP 28 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 419 AM EDT MON SEP 28 2015
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW ZONAL FLOW ALONG
THE CNDN BORDER AS RATHER SHEARED SHRTWV STRETCHING FM THE NRN
PLAINS INTO NW ONTARIO HAS WEAKENED THE UPR RDG THAT HAS BEEN SO
PERSISTENT RECENTLY OVER ERN NAMERICA. THIS SHRTWV IS SUPPORTING A
SFC COLD FNT THAT IS MOVING E THRU WRN LK SUP EARLY THIS MRNG. SINCE
THIS DISTURBANCE IS SHEARED OUT AND THE MSTR INFLOW IN THE SW FLOW
AHEAD OF THE FNT IS RATHER MODEST...SHOWER COVERAGE AHEAD OF THE
INCOMING FNT IS RATHER LIMITED...WITH SCT COVERAGE LIMITED BY THE
HIER STABILITY/DRY MID LVLS SHOWN ON THE 00Z MPX RAOB. CLDS IN
ADVANCE OF THE FNT ARE PUSHING THRU THE WRN CWA...BUT THERE IS AN
AXIS OF MOCLR SKIES OVER THE CENTRAL TO W OF SOME LO CLDS ACRS THE SE
HALF OF THE CWA ASSOCIATED WITH LLVL MSTR SHOWN ON THE 00Z GRB/APX
RAOBS. STEADY SW WINDS IN THE WARM SECTOR ARE KEEPING TEMPS WELL
ABOVE NORMAL NOT FAR FM 60 EVEN WHERE THE SKY IS MOCLR. LOOKING
FARTHER TO THE W...THE 00Z ABERDEEN SDAKOTA ROAB SHOWS A VERY DRY
AIRMASS IS UNDER SFC HI PRES RDG TRAILING THE SFC COLD FNT. BUT
FARTHER TO THE W...THERE IS AN AREA OF COLDER CLD TOPS/SHOWERS/EVEN
SOME LTG STRIKES MOVING THRU THE NRN PLAINS. MODELS SHOW AREA OF UPR
DVGC/MID LVL FGEN IN RRQ OF 100KT H3 JET MAX SUPPORTING THE NW
ONTARIO SHRTWV IS OVER THIS AREA OF COLDER CLD TOPS. ANOTHER SHRTWV
IS DIGGING THRU SCENTRAL CANADA AND DEEPENING AN UPR TROF THERE.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS ASSOCIATED WITH
COLD FNT THAT WL BE CROSSING UPR MI TODAY.
TODAY...LATEST SHORT TERM GUIDANCE IS IN GOOD AGREEMENT SHOWING SFC
COLD FNT CROSSING UPR MI TODAY AND REACHING LK MI ARND 21Z. SINCE
UPR DVGC/AXIS OF MID LVL FGEN SUPPORTING AREA OF DISTURBED WX IN THE
NRN PLAINS IS FCST TO MOVE OVER THE UPR LKS WHILE THE FNT IS
CROSSING THE CWA...MOST OF THE MODELS SHOW SHOWER COVERAGE EXPANDING
WITH TIME. SINCE THE DRY AIR SHOWN ON THE ABERDEEN RAOB AND TRAILING
THE FNT IS MOST LIKELY TO IMPACT THE WRN CWA BEFORE THE ARRIVAL...WL
FCST THE HIEST LIKELY POPS OVER THE SE HALF OF UPR MI THIS AFTN.
ALTHOUGH THERE HAVE BEEN SOME LTG STRIKES OBSVD UPSTREAM...MODEL
FCST MUCAPES NO HIER THAN ABOUT 100 J/KG OVER THE CWA SUPPORT
LEAVING TS OUT OF THE FCST FOR NOW. WITH EARLIER COLD FROPA OVER THE
W...TEMPS THERE WL BE MUCH LOWER THAN YDAY.
TNGT...MODELS DIFFER ON HOW QUICKLY THE SHOWERS EXIT THE SE CWA THIS
EVNG. THE 00Z NAM IS QUITE A BIT SLOWER THAN THE REST OF THE
GUIDANCE...BUT FAVOR THE FASTER DRYING TREND SHOWN BY THE MAJORITY
OF THE OTHER MODELS GIVEN DRYNESS OF THE TRAILING AIRMASS DEPICTED
ON THE 00Z ABERDEEN RAOB. THESE MODELS FAVOR SOME LINGERING HIER
LIKELY POPS EARLY IN THE EVNG OVER THE SE BEFORE VIGOROUS DRYING
BRINGS A CLRG TREND EVEN THOUGH ANOTHER COLD FNT ASSOCIATED WITH
SHRTWV NOW DIGGING THRU SCENTRAL CANADA IS PROGGED TO PASS OVERNGT.
H85 TEMPS DROPPING TO ARND 0C OVER THE KEWEENAW BY 12Z TUE WL RESULT
IN A MUCH COOLER OVERNGT WITH MIN TEMPS DIPPING TO ARND 40 AND
PERHAPS THE UPR 30S AT SOME OF THE HIER TERRAIN LOCATIONS. STRONG NW
FLOW OVER THE RELATIVELY WARM LK WATERS WL LIMIT THE TEMP DROP.
ALTHOUGH THE SFC-H85 DELTA T BTWN THE RELATIVELY WARM LK WATERS /MID
TO UPR 50S F/IS SUFFICIENT FOR LK CLDS/PCPN...THE INCOMING AIRMASS
WL BE TOO DRY AND THE LLVL FLOW TOO ACYC TO SUPPORT MORE THAN SCT
CLDS OVER THE HIER TERRAIN.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 409 AM EDT MON SEP 28 2015
UPPER LEVEL TROUGH FROM HUDSON BAY TO UPPER GREAT LAKES SLIDES TO
EASTERN CANADA LATE THIS WEEK WHILE HEIGHTS SLOWLY REBOUND FM
NORTHERN PLAINS TO UPPER GREAT LAKES. TROUGH WILL ENSURE A COOLER
WEEK WITH FROST/FREEZE OVER PARTS OF CWA TUE NIGHT AND MAYBE WED
NIGHT AS WELL.
ON TUESDAY...COOLER AIR ARRIVES WITH H85 TEMPS DOWN TO 0C TO -1C BY
AFTN. NORTHWEST WINDS COULD BE GUSTY UP TO 25 MPH...ESPECIALLY
CLOSER TO LK SUPERIOR. THOUGH APPROACHING HIGH IS THE DOMINANT
FACTOR...NAM/GFS/GEM-REGIONAL INDICATE HIGHER H85 RH MOVING ACROSS
LK SUPERIOR BY 12Z AND EXPANDING BY 18Z AS THE COOLER AIR ARRIVES.
ENVISION FEW-SCT STRATOCU CLOUDS EXPANDING INTO A STRATOCU/CUMULUS
DECK MAINLY CNTRL CWA BY AFTN...THEN DIMINISHING THROUGH THE REST OF
AFTN. WITH THE CLOUDS AND COLD AIR ADVECTION...TEMPS WILL ONLY REACH
LOW TO MID 50S NEAR LK SUPERIOR AND MAY TOUCH 60 DEGREES IN THE FAR
SCNTRL. EVEN THOUGH SWIM RISK WILL BE HIGH ALONG MARQUETTE AND ALGER
COUNTIES...AIR TEMPERATURES BELOW 55 DEGREES WILL PROHIBIT THE
ISSUANCE OF A BEACH HAZARDS STATEMENT.
NEXT UP IS TUE NIGHT AND THE FROST/FREEZE POTENTIAL. UPSHOT IS THE
FROST/FREEZE POTENTIAL...AT LEAST AWAY FM THE INTERIOR WEST...IS NOT
AS CLEAR CUT AS IT LOOKED THE LAST FEW DAYS. RECENTLY IN THE
MODELS...IT APPEARED THAT THE APPROACHING HIGH WOULD SETTLE RIGHT
OVERHEAD TUESDAY NIGHT. NOW...RIDGE AXIS STAYS MAINLY OVER WESTERN
UPR MICHIGAN WHILE A LIGHT BUT PERSISTENT NE LOW-LEVEL FLOW AFFECTS
EAST HALF OF CWA /SEE THIS AS 950-900MB WINDS OVER 10 KTS FM NCNTRL
INTO EASTERN CWA. ALSO...WITH H85 TEMPS STAYING AROUND -1C OVERNIGHT
TUESDAY NIGHT AND MORE OF AN ONSHORE WIND WITH SOME 875MB-850MB
MOISTURE SHOWN ON GFS/NAM SOUNDINGS...MAY HAVE TO CONTEND WITH SCT-
BKN LAKE EFFECT CLOUDS AS DELTA T VALUES WILL BE OVER 15C. BEST
CHANCE FOR BKN CLOUDS WOULD BE OVER FAR NCNTRL UPR MICHIGAN AND
ACROSS THE KEWEENAW. ADJUSTED SKY GRIDS TO BUMP UP CLOUD COVER FOR
THERE AREAS...ESPECIALLY FOR THE KEWEENAW. FOR TEMPS...USED GUIDANCE
THAT SHOWED LOWEST TEMPS IN THE UPR 20S OVER INTERIOR WEST BUT KEPT
READINGS MAINLY MID-UPR 30S WHERE CLOUDS MAY DISRUPT COOLING.
AFTER A MOSTLY SUNNY BUT COOL DAY ON WED...ANOTHER CHILLY NIGHT WITH
SOME FROST SEEMS PROBABLE FOR WED NIGHT. SETUP IS NO BETTER THAN TUE
NIGHT THOUGH AS HIGH CENTER IS MORE OVER QUEBEC AND THAT LEAVES A
LIGHT EASTERLY FLOW ACROSS UPR MICHIGAN. EVEN SO...MIN TEMPS MAY BE
AT LEAST IN LOWER 30S...ESPECIALLY OVER INLAND AREAS. DAYTIME HIGHS
WED INTO THU SHOULD STAY IN THE 50S TO AROUND 60 DEGREES. THESE
VALUES ARE PRETTY SEASONABLE FOR LATE SEPTEMBER...THOUGH MUCH COOLER
THAN THE WELL ABOVE NORMAL TEMPS SEEN MUCH OF THIS MONTH.
AFTER SOME RAIN TODAY...DRIER TREND THAT BEGAN TO SHOW UP IN THE
MODELS LAST COUPLE DAYS CONTINUES AS HIGH PRESSURE BUILDING IN
BEHIND COLD FRONTAL PASSAGE TODAY EXPANDS ACROSS THE UPPER GREAT
LAKES ON WED AND BUILDS FURTHER TO OVER 1040MB IN QUEBEC ON FRIDAY.
RIDGE FM THE HIGH EXPANDS WESTWARD ACROSS THE UPPER GREAT LAKES AND
AS FAR WEST AS SASKATCHEWAN AND MANITOBA. AT FIRST GLANCE...THIS
SHOULD KEEP MAJORITY OF REGION DRY THROUGH THE UPCOMING WEEKEND.
HOWEVER...GFS AND 12Z ECMWF INDICATE THAT DECENT STRENGTH SHORTWAVE
TROUGH BREAKING FREE FM THE LARGER SCALE TROUGH OVER EASTERN CANADA
WILL SLIDE OVER UPR GREAT LAKES FRIDAY INTO THE WEEKEND. 00Z ECMWF
NOT NEAR AS DEEP WITH TROUGH AS IT SHOWED WITH 12Z RUN THOUGH. DEEP
MOISTURE APPEARS SPOTTY BUT THERE ARE HINTS THERE MAY BE ENOUGH
FORCING AND MOISTURE TO SUPPORT SOME SHOWERS. OVERALL MOST CWA WILL
REMAIN DRY THROUGH NEXT WEEKEND AS UPPER LEVEL TROUGH WILL BE
LACKING LOW-LEVEL SUPPORT AS THE SFC HIGH REMAINS THE DOMINANT
WEATHER FEATURE. IF THERE ENDS UP BEING BETTER CYCLONIC FLOW IN LOW-
LEVELS AS 12Z ECMWF INDICATED...COULD SEE HELP FM LK SUPERIOR FOR
PRECIP AS H85 TEMPS ARE FORECAST TO BE AS LOW AS -3C WITH THE UPPER
TROUGH OVERHEAD. DAYTIME HIGHS SHOULD SETTLE BACK INTO THE 50S
FRIDAY AND SATURDAY WITH THE COOLER TEMPS ALOFT.
FINALLY...GFS IS MUCH MORE AGGRESSIVE THAN ECMWF WITH SECONDARY
STRONGER SHORTWAVE TROUGH MOVING THROUGH IN MORE TYPICAL NW TO SE
PROGRESSION LATE NEXT WEEKEND INTO EARLY NEXT WEEK /DAYS 8-10/. H85
TEMPS AS LOW AS -9C IN THE CORE OF THE COLDEST AIR OVER ONTARIO WITH
AROUND -5C OVER UPR MICHIGAN LAST TWO RUNS. NEITHER THE 12Z RUN OR
MOST RECENT 00Z RUN OF ECMWF SHOWED ADDITIONAL TROUGHING THOUGH WITH
RIDGING RE APPEARING INTO NEXT WEEK IN WAKE OF THE WEEKEND
TROUGHING. ECMWF DOES INDICATE TROUGHING AND SIMILAR DEGREE OF COLD
AIR...BUT IT STAYS WELL UPSTREAM OVER NORTHWEST CANADA MOST OF THE
WEEK. FOR THE FORECAST...CONSENSUS SHOULD COVER IT ATTM. USUALLY DO
NOT GET TOO CONCERNED WITH THESE TYPE OF DETAILS IN THE FAR REACHES
OF EXTENDED AND BEYOND...BUT GIVEN THE VERY WARM SEPTEMBER ABOUT TO
CONCLUDE /POTENTIALLY RECORD WARMEST AT SOME LOCATIONS ACROSS UPR
MICHIGAN/...IT IS NOTABLE THAT SOME MODELS ARE HINTING AT COOLER
AIRMASSES CLOSE BY AS FIRST FULL WEEK OF OCTOBER ARRIVES. OFFICIAL
8-14 DAY AND EXPERIMENTAL 3-4 WEEK FORECASTS FM CPC STILL INDICATING
WARMER THAN NORMAL TEMPERATURES SHOULD PREVAIL OVERALL THROUGH MUCH
OF NEXT MONTH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1150 PM EDT SUN SEP 27 2015
VFR CONDITIONS WILL GRADUALLY GIVE WAY TO MVFR CIGS AND SCATTERED
SHOWERS LATE TONIGHT INTO EARLY MONDAY MORNING AND LATE MON MORNING
AT KSAW ALONG/AHEAD OF AN ADVANCING COLD FRONT. SHOWERS WILL ONLY
LAST A FEW HOURS AT EACH TERMINAL WITH IMPROVING CONDITIONS FROM THE
WEST THROUGH THE DAY ON MONDAY AS NW WINDS BRING DRIER AIR INTO THE
REGION. LLWS IS EXPECTED AT ALL SITES THROUGH AT LEAST 12Z MON.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 419 AM EDT MON SEP 28 2015
SW WINDS UP TO 25 KTS THIS MRNG AHEAD OF A COLD FRONT MOVING THRU
WESTERN LAKE SUPERIOR EARLY THIS MORNING WILL SHIFT TO THE W-NW UP
TO 20 KTS FOLLOWING THE FRONTAL PASSAGE BY EARLY AFTERNOON OVER THE
FAR EAST. ANOTHER COLD FRONT WILL SWING ACROSS THE LAKE TONIGHT.
EXPECT NNW WINDS TO INCREASE UP TO 25-30 KTS IN ITS WAKE LATE
TONIGHT/TUE. AS A TRAILING HIGH PRESSURE CLOSES IN ON THE AREA ON
TUE NIGHT/WED...WINDS WILL DIMINISH TO UNDER 15-20 KTS. ONCE THE
HIGH SHIFTS INTO QUEBEC LATER IN THE WEEK...E WINDS UP TO 20 KTS
WILL DOMINATE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...VOSS
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
410 AM EDT MON SEP 28 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 412 PM EDT SUN SEP 27 2015
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A MID/UPPER RIDGE
EXTENDING FROM THE DESERT SW TO SE CANADA WHILE A TROF IS
PROGRESSING THRU WRN CANADA. AT THE SFC...THE TROF IS SUPPORTING A
COLD FRONT EXTENDING FROM CNTRL SD ACROSS FAR NW MN TO HUDSON BAY.
SW FLOW BTWN THE COLD FRONT AND SFC HIGH PRES CENTERED JUST OFF THE
NEW ENGLAND COAST HAS LED TO ANOTHER UNSEASONABLY WARM LATE SEPT DAY
TODAY. TEMPS ARE CURRENTLY WELL INTO THE 70S ACROSS MOST OF UPPER MI
WITH A FEW LOCATIONS...MAINLY IN THE DOWNSLOPE AREAS NEAR LAKE
SUPERIOR...AROUND 80F. FOG/STRATUS THAT WAS OVER CNTRL UPPER MI
EARLY THIS MORNING BURNED OFF BY LATE MORNING. STRATOCU THAT WAS
OVER IL/SE WI/LAKE MI EARLY TODAY HAS SPREAD N. WHILE STILL S OF
KMNM...THE AREA OF MOISTURE HAS LED TO MORE CLOUD COVER FROM AROUND
KISQ/KERY EASTWARD. OTHERWISE...SKIES ARE MOSTLY SUNNY.
DURING THE SHORT TERM...FOCUS WILL BE ON CLOUD TRENDS THIS EVENING
FOR VIEWING LUNAR ECLIPSE AND THEN PCPN POTENTIAL AS WRN CANADA TROF
CONTINUES EASTWARD...PUSHING SFC COLD FRONT ACROSS THE AREA MON.
WITH COLD FRONT APPROACHING...MODELS SHOW WINDS IN THE APPROACHING
CLOUD BEARING LAYER (ROUGHLY 875-850MB) VEERING SOME TONIGHT.
THUS...THE DIRECTION OF MOVEMENT OF THE STRATOCU APPROACHING FROM S
SHOULD TEND TO TAKE ON MORE OF AN EASTERLY COMPONENT WITH TIME. AT
THIS POINT...IT APPEARS LOCATIONS ROUGHLY EAST OF AN IRON MTN TO
MUNISING LINE WILL HAVE THE MOST CLOUD COVER...POTENTIALLY OBSCURING
MUCH OF THE LUNAR ECLIPSE THIS EVENING AT A FEW LOCATIONS. NAM IN
PARTICULAR IS AGGRESSIVE IN MOISTENING LOWER LEVELS BLO STRATOCU
LAYER FARTHER TO THE W...BUT DON`T THINK THIS WILL TRANSLATE TO LOW
CLOUD DEVELOPMENT THIS EVENING EVEN IF IT IS CORRECT WITH THE
MOISTURE.
ATTENTION THEN TURNS TO APPROACHING COLD FRONT. THERE ARE ONLY VERY
MINOR DIFFERENCES IN THE MODELS IN TIMING FRONT ACROSS THE AREA...
REACHING THE W EARLY MON MORNING AND EXITING THE SE LATE AFTN.
GUIDANCE SUPPORTS SCT/CHC POPS LATE TONIGHT OVER THE W. BIGGER
UNCERTAINTY CONTINUES TO BE WHETHER THE UPPER JET CONFIGURATION WITH
RIGHT ENTRANCE UPPER DIVERGENCE AND LOW/MID LEVEL FGEN UNDERNEATH
WILL BE SUFFICENT TO HELP DEVELOP A HEAVIER/MORE SOLID BAND OF SHRA
JUST BEHIND THE FRONT AS IT MOVES SE ACROSS THE AREA MON. THE
MAJORITY OF GUIDANCE SUPPORTS THE IDEA OF IMPROVED FORCING LEADING
TO AN INCREASE IN SHRA COVERAGE ACROSS AT LEAST THE SCNTRL AND ERN
FCST AREA MON AFTN. WITH THE LAST FEW HRS OF THE LATEST RAP RUN
ENDING AT 12Z MON APPEARING TO SUPPORT THAT IDEA AS IT HAS STRONGER
FORCING DEVELOPING TO THE W AT THE END OF THE MODEL RUN...WILL RAISE
POPS FOR MON...ESPECIALLY SCNTRL AND E WHERE LIKELY/NMRS WILL BE
UTILIZED LATE. NOT OUT OF THE QUESTION THAT THERE COULD BE A FEW
RUMBLES OF THUNDER...BUT POTENTIAL IS TOO LOW AT THIS POINT TO
INCLUDE MENTION.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 409 AM EDT MON SEP 28 2015
UPPER LEVEL TROUGH FROM HUDSON BAY TO UPPER GREAT LAKES SLIDES TO
EASTERN CANADA LATE THIS WEEK WHILE HEIGHTS SLOWLY REBOUND FM
NORTHERN PLAINS TO UPPER GREAT LAKES. TROUGH WILL ENSURE A COOLER
WEEK WITH FROST/FREEZE OVER PARTS OF CWA TUE NIGHT AND MAYBE WED
NIGHT AS WELL.
ON TUESDAY...COOLER AIR ARRIVES WITH H85 TEMPS DOWN TO 0C TO -1C BY
AFTN. NORTHWEST WINDS COULD BE GUSTY UP TO 25 MPH...ESPECIALLY
CLOSER TO LK SUPERIOR. THOUGH APPROACHING HIGH IS THE DOMINANT
FACTOR...NAM/GFS/GEM-REGIONAL INDICATE HIGHER H85 RH MOVING ACROSS
LK SUPERIOR BY 12Z AND EXPANDING BY 18Z AS THE COOLER AIR ARRIVES.
ENVISION FEW-SCT STRATOCU CLOUDS EXPANDING INTO A STRATOCU/CUMULUS
DECK MAINLY CNTRL CWA BY AFTN...THEN DIMINISHING THROUGH THE REST OF
AFTN. WITH THE CLOUDS AND COLD AIR ADVECTION...TEMPS WILL ONLY REACH
LOW TO MID 50S NEAR LK SUPERIOR AND MAY TOUCH 60 DEGREES IN THE FAR
SCNTRL. EVEN THOUGH SWIM RISK WILL BE HIGH ALONG MARQUETTE AND ALGER
COUNTIES...AIR TEMPERATURES BELOW 55 DEGREES WILL PROHIBIT THE
ISSUANCE OF A BEACH HAZARDS STATEMENT.
NEXT UP IS TUE NIGHT AND THE FROST/FREEZE POTENTIAL. UPSHOT IS THE
FROST/FREEZE POTENTIAL...AT LEAST AWAY FM THE INTERIOR WEST...IS NOT
AS CLEAR CUT AS IT LOOKED THE LAST FEW DAYS. RECENTLY IN THE
MODELS...IT APPEARED THAT THE APPROACHING HIGH WOULD SETTLE RIGHT
OVERHEAD TUESDAY NIGHT. NOW...RIDGE AXIS STAYS MAINLY OVER WESTERN
UPR MICHIGAN WHILE A LIGHT BUT PERSISTENT NE LOW-LEVEL FLOW AFFECTS
EAST HALF OF CWA /SEE THIS AS 950-900MB WINDS OVER 10 KTS FM NCNTRL
INTO EASTERN CWA. ALSO...WITH H85 TEMPS STAYING AROUND -1C OVERNIGHT
TUESDAY NIGHT AND MORE OF AN ONSHORE WIND WITH SOME 875MB-850MB
MOISTURE SHOWN ON GFS/NAM SOUNDINGS...MAY HAVE TO CONTEND WITH SCT-
BKN LAKE EFFECT CLOUDS AS DELTA T VALUES WILL BE OVER 15C. BEST
CHANCE FOR BKN CLOUDS WOULD BE OVER FAR NCNTRL UPR MICHIGAN AND
ACROSS THE KEWEENAW. ADJUSTED SKY GRIDS TO BUMP UP CLOUD COVER FOR
THERE AREAS...ESPECIALLY FOR THE KEWEENAW. FOR TEMPS...USED GUIDANCE
THAT SHOWED LOWEST TEMPS IN THE UPR 20S OVER INTERIOR WEST BUT KEPT
READINGS MAINLY MID-UPR 30S WHERE CLOUDS MAY DISRUPT COOLING.
AFTER A MOSTLY SUNNY BUT COOL DAY ON WED...ANOTHER CHILLY NIGHT WITH
SOME FROST SEEMS PROBABLE FOR WED NIGHT. SETUP IS NO BETTER THAN TUE
NIGHT THOUGH AS HIGH CENTER IS MORE OVER QUEBEC AND THAT LEAVES A
LIGHT EASTERLY FLOW ACROSS UPR MICHIGAN. EVEN SO...MIN TEMPS MAY BE
AT LEAST IN LOWER 30S...ESPECIALLY OVER INLAND AREAS. DAYTIME HIGHS
WED INTO THU SHOULD STAY IN THE 50S TO AROUND 60 DEGREES. THESE
VALUES ARE PRETTY SEASONABLE FOR LATE SEPTEMBER...THOUGH MUCH COOLER
THAN THE WELL ABOVE NORMAL TEMPS SEEN MUCH OF THIS MONTH.
AFTER SOME RAIN TODAY...DRIER TREND THAT BEGAN TO SHOW UP IN THE
MODELS LAST COUPLE DAYS CONTINUES AS HIGH PRESSURE BUILDING IN
BEHIND COLD FRONTAL PASSAGE TODAY EXPANDS ACROSS THE UPPER GREAT
LAKES ON WED AND BUILDS FURTHER TO OVER 1040MB IN QUEBEC ON FRIDAY.
RIDGE FM THE HIGH EXPANDS WESTWARD ACROSS THE UPPER GREAT LAKES AND
AS FAR WEST AS SASKATCHEWAN AND MANITOBA. AT FIRST GLANCE...THIS
SHOULD KEEP MAJORITY OF REGION DRY THROUGH THE UPCOMING WEEKEND.
HOWEVER...GFS AND 12Z ECMWF INDICATE THAT DECENT STRENGTH SHORTWAVE
TROUGH BREAKING FREE FM THE LARGER SCALE TROUGH OVER EASTERN CANADA
WILL SLIDE OVER UPR GREAT LAKES FRIDAY INTO THE WEEKEND. 00Z ECMWF
NOT NEAR AS DEEP WITH TROUGH AS IT SHOWED WITH 12Z RUN THOUGH. DEEP
MOISTURE APPEARS SPOTTY BUT THERE ARE HINTS THERE MAY BE ENOUGH
FORCING AND MOISTURE TO SUPPORT SOME SHOWERS. OVERALL MOST CWA WILL
REMAIN DRY THROUGH NEXT WEEKEND AS UPPER LEVEL TROUGH WILL BE
LACKING LOW-LEVEL SUPPORT AS THE SFC HIGH REMAINS THE DOMINANT
WEATHER FEATURE. IF THERE ENDS UP BEING BETTER CYCLONIC FLOW IN LOW-
LEVELS AS 12Z ECMWF INDICATED...COULD SEE HELP FM LK SUPERIOR FOR
PRECIP AS H85 TEMPS ARE FORECAST TO BE AS LOW AS -3C WITH THE UPPER
TROUGH OVERHEAD. DAYTIME HIGHS SHOULD SETTLE BACK INTO THE 50S
FRIDAY AND SATURDAY WITH THE COOLER TEMPS ALOFT.
FINALLY...GFS IS MUCH MORE AGGRESSIVE THAN ECMWF WITH SECONDARY
STRONGER SHORTWAVE TROUGH MOVING THROUGH IN MORE TYPICAL NW TO SE
PROGRESSION LATE NEXT WEEKEND INTO EARLY NEXT WEEK /DAYS 8-10/. H85
TEMPS AS LOW AS -9C IN THE CORE OF THE COLDEST AIR OVER ONTARIO WITH
AROUND -5C OVER UPR MICHIGAN LAST TWO RUNS. NEITHER THE 12Z RUN OR
MOST RECENT 00Z RUN OF ECMWF SHOWED ADDITIONAL TROUGHING THOUGH WITH
RIDGING RE APPEARING INTO NEXT WEEK IN WAKE OF THE WEEKEND
TROUGHING. ECMWF DOES INDICATE TROUGHING AND SIMILAR DEGREE OF COLD
AIR...BUT IT STAYS WELL UPSTREAM OVER NORTHWEST CANADA MOST OF THE
WEEK. FOR THE FORECAST...CONSENSUS SHOULD COVER IT ATTM. USUALLY DO
NOT GET TOO CONCERNED WITH THESE TYPE OF DETAILS IN THE FAR REACHES
OF EXTENDED AND BEYOND...BUT GIVEN THE VERY WARM SEPTEMBER ABOUT TO
CONCLUDE /POTENTIALLY RECORD WARMEST AT SOME LOCATIONS ACROSS UPR
MICHIGAN/...IT IS NOTABLE THAT SOME MODELS ARE HINTING AT COOLER
AIRMASSES CLOSE BY AS FIRST FULL WEEK OF OCTOBER ARRIVES. OFFICIAL
8-14 DAY AND EXPERIMENTAL 3-4 WEEK FORECASTS FM CPC STILL INDICATING
WARMER THAN NORMAL TEMPERATURES SHOULD PREVAIL OVERALL THROUGH MUCH
OF NEXT MONTH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1150 PM EDT SUN SEP 27 2015
VFR CONDITIONS WILL GRADUALLY GIVE WAY TO MVFR CIGS AND SCATTERED
SHOWERS LATE TONIGHT INTO EARLY MONDAY MORNING AND LATE MON MORNING
AT KSAW ALONG/AHEAD OF AN ADVANCING COLD FRONT. SHOWERS WILL ONLY
LAST A FEW HOURS AT EACH TERMINAL WITH IMPROVING CONDITIONS FROM THE
WEST THROUGH THE DAY ON MONDAY AS NW WINDS BRING DRIER AIR INTO THE
REGION. LLWS IS EXPECTED AT ALL SITES THROUGH AT LEAST 12Z MON.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 412 PM EDT SUN SEP 27 2015
AHEAD OF AN APPROACHING COLD FRONT...S TO SW WINDS ACROSS LAKE
SUPERIOR WILL GUST TO AROUND 25KT TONIGHT...BUT UP TO 30KT AT THE
HIGHEST OBS PLATFORMS. THE FRONT WILL CROSS LAKE SUPERIOR LATE
TONIGHT AND MON...BRINGING A WIND SHIFT TO THE W TO NW WITH SPEEDS
GENERALLY UNDER 20KT. AN UPTICK IN WINDS IS EXPECTED MON NIGHT/TUE
TO 20-30KT...ESPECIALLY OVER CNTRL AND EASTERN LAKE SUPERIOR AS
INSTABILITY INCREASES WITH INCREASINGLY COLDER AIR FLOWING OVER THE
LAKE AHEAD OF APPROACHING HIGH PRES. WINDS WILL THEN DIMINISH TO
UNDER 15KT W TO E TUE NIGHT AS HIGH PRES SETTLES OVER THE UPPER
LAKES. THE HIGH PRES WILL THEN DRIFT TO THE ENE WED THRU FRI...BUT
WILL MAINTAIN RIDGING BACK INTO THE UPPER LAKES. AS A RESULT...WHILE
WINDS WILL INCREASE SOME...SPEEDS SHOULD REMAIN MOSTLY 20KT OR LESS
DURING THE LAST HALF OF THE WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS GAYLORD MI
233 AM EDT MON SEP 28 2015
.UPDATE...
ISSUED AT 1011 PM EDT SUN SEP 27 2015
LOW CLOUDS (UNFORTUNATELY) CONTINUE TO HANG OVER ALMOST ALL OF OUR
CWA LATE THIS EVENING...WITH THE EXCEPTION OF FAR WRN SECTIONS OF
CHIPPEWA AND MACKINAC COUNTIES RIGHT ALONG THE NW EDGE OF THIS
LOW CLOUD DECK. BAD TIMING TO HAVE A CLOUDY NIGHT GIVEN THE RARE
SUPERMOON LUNAR ECLIPSE HAPPENING AS I WRITE. EXPECT THESE CLOUDS
WILL REMAIN IN PLACE ALL NIGHT. A FEW REGION OBS HAVE ACTUALLY
REPORTED SOME VERY LIGHT SHOWER ACTIVITY...AND HAVE ADDED THIS TO
THE FORECAST FOR THE BALANCE OF THE NIGHT. BOTH THE LATEST RAP13
AND HRRR SUPPORT THIS NOTION. TEMPS WILL ONLY FALL A FEW DEGREES
AS WE HEAD INTO THE OVERNIGHT HOURS...WITH LOW TEMPS COOLING INTO
THE UPPER 50S AND LOWER 60S.
&&
.NEAR TERM...(THIS EVENING THROUGH TONIGHT)
ISSUED AT 414 PM EDT SUN SEP 27 2015
...SORRY FOR THE CLOUDS LUNAR ECLIPSE VIEWERS...
MID LEVEL MOISTURE CONTINUES TO STREAM NORTHWARD INTO NORTHERN
MICHIGAN. THIS HAS RESULTED IN MOSTLY CLOUDY SKIES ACROSS THE REGION
AS EXPECTED. HOWEVER THERE IS AT LEAST A LITTLE HOPE ON THE HORIZON
AS SATELLITE IMAGERY DOES SHOW A FEW HOLES IN THE CLOUD COVER
UPSTREAM. SO ALTHOUGH IT MAY BE TOUGH TO SEE THE LUNAR ECLIPSE...A
FEW OCCASIONAL GLIMPSES ARE STILL POSSIBLE AT TIMES THIS
EVENING...DESPITE THE ABUNDANT CLOUD COVER. THERE ARE QUESTIONS
OVERNIGHT ABOUT THE EXTENT OF CLOUD COVER AS MOISTURE BEGINS TO
DIMINISH (1000-500 MB RH FALLS FROM BETWEEN 60 AND 80 PERCENT TO
BETWEEN 50 AND 70 PERCENT)...BUT ANY PARTIAL CLEARING WILL LIKELY
LEAD TO AREAS OF STRATUS FORMATION. MILDER WITH SOUTH WINDS KEEPING
LOWS IN THE UPPER 50S TO MIDDLE 60S.
&&
.SHORT TERM...(MONDAY THROUGH WEDNESDAY)
ISSUED AT 414 PM EDT SUN SEP 27 2015
...HEADLINES..
HIGH IMPACT WEATHER POTENTIAL: NON-SEVERE CONVECTION MONDAY
AFTERNOON/EVENING. FROST POSSIBLE WEDNESDAY MORNING.
PATTERN SYNOPSIS/FORECAST: MAIN WESTERLIES DISPLACED WELL NORTH
ACROSS CANADA...WITH WEAK UPPER LEVEL FLOW AND EMBEDDED DISTURBANCES
ACROSS THE SOUTHERN/EASTERN CONTINENTAL U.S. NORTHERN PORTION OF A
SPLITTING TROUGH CROSSING WESTERN/CENTRAL CANADA...WITH A PIECE OF
ENERGY LEFT BEHIND AROUND 140W. MEANWHILE...DISTURBANCES CAUGHT IN
WEAK FLOW INCLUDE ONE OVER TEXAS/WESTERN GULF OF MEXICO...A
SUBTROPICAL DISTURBANCE SOUTH OF BERMUDA NEAR 60W...AND A WEAKENING
FEATURE OVER THE MID ATLANTIC STATES. AT THE SURFACE...1034MB HIGH
STRETCHING ACROSS NEW ENGLAND/NOVA SCOTIA RIDGING WEST INTO THE
GREAT LAKES/OHIO VALLEY. PLENTY OF MOISTURE OVER THE SOUTHEAST
QUADRANT OF THE COUNTRY...WITH 60S DEW POINTS/BOUNDARY LAYER MIXING
RATIOS >10G/KG CREEPING AROUND THE PERIPHERY OF THE ANTICYCLONE AND
INTO ILLINOIS/INDIANA/SOUTHWEST LOWER MICHIGAN. COLD FRONT EXTENDS
FROM NORTHWEST ONTARIO INTO THE DAKOTAS/NORTHERN WYOMING.
HEIGHT FALLS ASSOCIATED WITH THE SHORT WAVE TROUGH OVER WESTERN
CANADA WILL HAVE THE BIGGEST SHORT TERM FORECAST IMPACT ON THE GREAT
LAKES FOR THE EARLY PART OF THIS WEEK...AS SOUTHERN PORTION OF THIS
WAVE WILL CLIP MICHIGAN IN THE MONDAY-TUESDAY TIME FRAME BEFORE
LIFTING OUT BY MIDWEEK WITH THE POSSIBILITY OF ANOTHER WEAKNESS
DEVELOPING OVER THE OHIO/TENNESSEE VALLEYS AND SOUTHEASTERN STATES
BY THURSDAY. UPSTREAM COLD FRONT WILL ARRIVE ACROSS NORTHERN
MICHIGAN MONDAY AFTERNOON...AND IS EXPECTED TO DROP INTO SOUTHERN
LOWER MICHIGAN AFTER MIDNIGHT TUESDAY WITH DECENT COLD ADVECTION IN
ITS WAKE. HIGH PRESSURE THEN BUILDS INTO MICHIGAN TUESDAY NIGHT/
WEDNESDAY.
PRIMARY FORECAST CONCERNS: PRECIPITATION CHANCES/AMOUNTS WITH COLD
FRONT MONDAY/MONDAY NIGHT...CHILLY TEMPERATURES WEDNESDAY MORNING?
MONDAY...COLD FRONT NOT EXPECTED TO ARRIVE ACROSS EASTERN UPPER
UNTIL MID AFTERNOON...BUT INCREASING LOW LEVEL MOISTURE AHEAD OF THE
FRONT WITH DEW POINTS CLIMBING INTO THE LOWER-MID 60S. SOME
INDICATIONS OF INSTABILITY DEVELOPING AHEAD OF THE FRONT ESPECIALLY
IN THE NAM-WRF WHICH IS (AS USUAL) BULLISH ON PULLING HIGHER DEW
POINTS INTO NORTHERN LOWER. THINK WHAT MAY OCCUR IS A MOSTLY POST-
FRONTAL RAIN BAND MOVING INTO EASTERN UPPER DURING MID/LATE
AFTERNOON...WHILE PRE-FRONTAL CONVECTION DEVELOPS ACROSS INTERIOR
NORTHERN LOWER DURING THE AFTERNOON. POSSIBLE THAT FAR SOUTHWEST
PORTIONS OF THE FORECAST AREA (MBL/FKS/TVC) MAY STAY DRY THROUGH THE
AFTERNOON. ONE LAST WARM AFTERNOON EXPECTED WITH HIGHS IN THE
70S. RAIN BAND SHOULD THEN PROGRESS SOUTHWARD ACROSS NORTHERN
MICHIGAN MONDAY NIGHT...AIDED BY RIGHT ENTRANCE REGION JET
FORCING. RAIN SHOULD PUSH SOUTH OF THE UPPER PENINSULA DURING THE
EARLY MORNING HOURS OF TUESDAY. GENERAL RAINFALL TOTALS OF
0.25-0.50 INCH EXPECTED THROUGH TUESDAY MORNING.
TUESDAY...WILL BE FIRMLY IN POST-COLD FRONT AIR MASS TUESDAY
MORNING...MOST OF THE PRECIPITATION SHOULD BE SOUTH OF THE FORECAST
AREA BUT CAN`T RULE OUT SOME LINGERING SHOWERS ACROSS SOUTHEAST
QUARTER OF THE FORECAST AREA ALLOWING FOR UNCERTAINTY IN FRONTAL
SPEED. BUT SHOULD BE CLEARING OUT BEYOND THAT AS COOLER/DRIER AIR
SPILL ACROSS NORTHERN MICHIGAN...AND MUCH COOLER THAN RECENT DAYS
WITH HIGHS IN THE UPPER 50S-MID 60S EXPECTED WITH A NORTHWEST
BREEZE. HIGH PRESSURE THEN BUILDS INTO MICHIGAN TUESDAY NIGHT ALONG
WITH A FLATTENING PRESSURE GRADIENT. POSSIBILITY OF GOOD
RADIATIONAL COOLING CONDITIONS MAY SET THE STAGE FOR A PRETTY GOOD
FROST ACROSS INTERIOR EASTERN UPPER/NORTHERN LOWER MICHIGAN
WEDNESDAY MORNING.
WEDNESDAY...SURFACE HIGH PRESSURE WILL REMAIN IN CONTROL
WEDNESDAY...SO ANOTHER NICE DAY ON TAP THOUGH TEMPERATURES WILL
REMAIN A FEW DEGREES BELOW END OF SEPTEMBER NORMALS.
&&
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 414 PM EDT SUN SEP 27 2015
A FAIRLY QUIET EXTENDED PERIOD IS ON TAP ACROSS NORTHERN MICHIGAN AS
SURFACE HIGH PRESSURE DOMINATES...PROVIDING DRY CONDITIONS AND
COOLER TEMPERATURES THROUGH AT LEAST SATURDAY. RECENT TRENDS HAVE
SLOWED NEXT WEEKEND`S DEVELOPMENT OF LOW PRESSURE OVER THE PLAINS
BEFORE SLIDING NORTHEASTWARD TOWARD THE GREAT LAKES. AT THIS
POINT...THERE`S FAIRLY LOW CONFIDENCE IN HOW THE DETAILS WILL PLAY
OUT FOR THE END OF NEXT WEEKEND AS INTERACTIONS...FROM BOTH THE
AFOREMENTIONED HIGH PRESSURE AND ANOTHER DEVELOPING LOW PRESSURE
CENTER OVER THE EASTERN SEABOARD...REMAIN UNCLEAR.
IT`S SAFE TO SAY THE AREA WILL RETURN TO TEMPERATURES MUCH MORE
REPRESENTATIVE OF CLIMATOLOGICAL NORMAL FOR THE FIRST WEEK OF
OCTOBER. HIGH TEMPS ARE EXPECTED TO RANGE FROM THE UPPER 50S TO
LOWER 60S WITH LOWS IN THE 30S TO LOW 40S THROUGHOUT THE PERIOD.
HAVE GONE AHEAD AND ADDED PATCHY FROST ON WEDNESDAY NIGHT FOR THE
TYPICAL COOLER/INTERIOR SPOTS IN NORTHERN LOWER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 233 AM EDT MON SEP 28 2015
LOW VFR/HIGH MVFR CIGS WILL PERSIST ACROSS NRN LOWER MICHIGAN
OVERNIGHT AND THROUGH MUCH OF THE DAY MONDAY...ALTHOUGH THERE
WILL BE BREAKS AT TIMES IN THE CLOUDS. DAYTIME HEATING ON MONDAY
MIGHT BUBBLE UP A FEW SHOWERS/ISOLATED THUNDER ACROSS NE LOWER
MICHIGAN IN THE AFTERNOON...RESULTING IN A LOWER END CHANCE FOR
SHOWERS AT APN. BUT A SLOW MOVING COLD FRONT WILL SAG INTO THE
REGION LATE MONDAY AFTERNOON/MONDAY NIGHT. EXPECT A QUICK LOWERING
OF CLOUD COVER TO MVFR WITH THE FRONT AS COOLER AIR BLEEDS INTO
THE REGION. HOWEVER...THERE WILL ALSO BE A NARROW BAND OF MORE
WIDESPREAD RAINFALL DEVELOPING BEHIND THE FRONT THAT WILL SLOWLY
FOLD INTO NRN LOWER MICHIGAN DURING THE COURSE OF THE NIGHT.
WINDS...SW 10 KNOTS OR LESS OVERNIGHT THROUGH MONDAY WITH SOME
LLWS OVERNIGHT. WINDS TURN INTO THE N/NW MONDAY EVENING WITH
PASSAGE OF THE FRONT...WITH SOME GUSTINESS ANTICIPATED.
&&
.MARINE...
ISSUED AT 414 PM EDT SUN SEP 27 2015
A WEAK UPPER LEVEL SYSTEM FLOATING AROUND THE MID ATLANTIC WILL
CONTINUE MOSTLY CLOUDY SKIES THROUGH TONIGHT. A COLD FRONT WITH
STRENGTHENING SW WINDS AHEAD OF IT FOR TONIGHT INTO MONDAY MORNING
WILL BRING SOME LOW END ADVISORY LEVEL WINDS WITH SMALL CRAFT
ADVISORIES REMAINING POSTED. THE FRONT ARRIVES BY MONDAY
EVENING...BRINGING AT LEAST SOME LIGHT RAIN THAT MAY LINGER INTO
TUESDAY MORNING.
NORTH NORTHWEST WINDS WILL LIKELY BECOME GUSTY TUESDAY WITH ANOTHER
ROUND OF SMALL CRAFT ADVISORIES POSSIBLE.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR LHZ347>349.
LM...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR LMZ341-342-
344>346.
LS...NONE.
&&
$$
UPDATE...MLR
NEAR TERM...SULLIVAN
SHORT TERM...JPB
LONG TERM...GILLEN
AVIATION...ADAM
MARINE...SULLIVAN
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1222 PM CDT MON SEP 28 2015
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 304 AM CDT MON SEP 28 2015
A WEAK COLD FRONT IS SLOWLY SLIDING SOUTHEAST ACROSS THE FORECAST
AREA EARLY THIS MORNING...GENERALLY DRAPED FROM LAKE SUPERIOR
SOUTHEAST ACROSS CENTRAL MINNESOTA AND ON INTO SOUTH DAKOTA. SOME
SCATTERED SHOWERS ARE AFFECTING NORTHWEST WISCONSIN OUT AHEAD OF
IT...BUT NOT BRINGING MUCH IN THE WAY OF PRECIPITATION. SOME FOG
HAS FORMED BEHIND THE FRONT...BUT VISIBILITIES ARE STILL IN THE 3-5
MILE RANGE AND DO NOT EXPECT CONDITIONS TO GET MUCH WORSE. THE
FRONT WILL CONTINUE TO SLIDE SOUTHEAST THIS MORNING...AND SHOULD BE
SOUTHEAST OF THE FORECAST AREA BY MID DAY. OF INTEREST ON SATELLITE
IMAGERY THIS MORNING IS A SHORTWAVE MOVING OUT OF WYOMING AND INTO
SOUTH DAKOTA...WITH SOME DECENTLY COLD CLOUD TOPS AND A FAIR AMOUNT
OF LIGHTNING WITH IT...SOMEWHAT UNUSUAL FOR THIS TIME OF YEAR AND
DAY. THUS...EXPECT THAT THIS PARTICULAR FEATURES IS PROBABLY
STRONGER THAN MOST OF THE MODELS SHOW...AND EXPECT IT TO CONTINUE TO
RIPPLE EAST ALONG THE COLD FRONT DURING THE DAY TODAY. BASED ON
THIS STRONGER FEATURE HAVE GONE WITH HIGHER POPS ACROSS MY
SOUTHEASTERN CWA DURING THE DAY TODAY...USING THE 06Z HRRR RUN FOR
THE GENERAL PLAN AND HAVE MADE SOME OTHER TWEAKS TO PLACE A BAND OF
SHOWERS AND ISOLATED THUNDERSTORMS ACROSS MY NW WISCONSIN COUNTIES
DURING THE DAYTIME TODAY...GENERALLY FROM 15Z TO 21Z.
OTHERWISE...IT SHOULD BE A FAIRLY DECENT DAY WITH HIGHS IN THE 60S
MOST LOCATIONS AND LIGHT WINDS. TONIGHT THE FRONT DROPS FAR ENOUGH
SOUTH THAT THE RIDGE OF HIGH PRESSURE CAN BUILD INTO THE AREA FOR
TONIGHT AND TUESDAY. THIS SHOULD SET US UP FOR A GOOD RADIATIONAL
COOLING NIGHT WITH CLEAR OR NEARLY CLEAR SKIES AND COLD TEMPERATURES
ALOFT TO ACCOMPANY THE COLD AIRMASS MOVING INTO THE AREA. LATEST
GUIDANCE INDICATES THAT WE WILL HAVE SOME 850MB TEMPS IN THE -3 C
RANGE BY 12Z. THIS SHOULD SET US UP FOR SOME CHILLY TEMPERATURES
TONIGHT...WITH LOWS DIPPING INTO EVEN THE UPPER 20S IN SOME OF OUR
COLD SPOTS AND 30S ELSEWHERE. FROST IS A REAL POSSIBILITY. HAVE
LEFT IT TO THE DAY SHIFT TO SEND OUT A FROST/FREEZE ADVISORY AS
SPECIFIC LOCATIONS ARE STILL SOMEWHAT IN QUESTION...BUT ANTICIPATE
THAT WE WILL NEED ONE OR BOTH FOR AT LEAST PARTS OF THE FORECAST
AREA. TUESDAY TO REMAIN CHILLY WITH HIGHS ONLY IN THE 50S IN THIS
CHILLY AIRMASS...AND THE DRY AIR TO BRING OUR MIN RH VALUES DOWN
INTO THE 20 PERCENT RANGE DURING THE AFTERNOON.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 304 AM CDT MON SEP 28 2015
LOW CONFIDENCE IN THE PATTERN LATE WEEK INTO THE WEEKEND DUE TO A
WIDE RANGE IN MODEL SOLUTIONS...BUT SOME NOTABLE TRENDS ARE
BEGINNING TO EMERGE. A COOL TUESDAY NIGHT WITH TEMPERATURES FALLING
TO NEAR FREEZING IN SOME LOCATIONS...THEN GENERALLY SEASONABLE
TEMPERATURES WITH LOW CHANCES FOR PRECIPITATION THROUGH THE REST OF
THE PERIOD.
ON THE SYNOPTIC SCALE THE LONG TERM PERIOD BEGINS WITH AN AMPLIFIED
RIDGE ACROSS THE INTERMOUNTAIN WEST AND BROAD TROUGH OVER THE
SOUTHEAST. AN AREA OF HIGH PRESSURE WILL BE DRIFTING EASTWARD WITH
WEST/SOUTHWEST FLOW AT LOW/MID LEVELS DEVELOPING ON WEDNESDAY. AS
THIS HIGH DEPARTS TUESDAY NIGHT TEMPS ARE EXPECTED TO FALL TO NEAR
FREEZING...MAINLY ACROSS INLAND NORTHWEST WISCONSIN BUT ALSO IN
POCKETS ACROSS THE IRON RANGE AND MN ARROWHEAD. AN EMBEDDED
SHORTWAVE TROUGH JUST AHEAD OF THE RIDGE AXIS WILL DIVE SOUTHWARD
FROM SASKATCHEWAN/MANITOBA INTO THE NORTHERN PLAINS. WHILE THE BEST
UPPER LEVEL FORCING WILL BE IN SOUTHERN MANITOBA...WITH WARM AIR
ADVECTION AND A FAIRLY DEEP LAYER OF MOISTURE IN PLACE THERE IS A
CHANCE FOR SHOWERS LATE WED/WED NIGHT ACROSS NORTHWEST TO EVEN NORTH
CENTRAL MINNESOTA...WITH THE BEST CHANCE TOWARDS THE BORDERLAND.
WHILE CLOUDS WILL BE PRESENT ACROSS MUCH OF NORTHERN MINNESOTA
WEDNESDAY...THEY SHOULD BEGIN TO CLEAR OUT THURSDAY AS EASTERLY LOW
LEVEL WINDS PREVAIL DUE TO AN 850/700 MB HIGH OVER ONTARIO.
FOR THE WEEKEND GUIDANCE IS ALL OVER THE PLACE WITH THE SYNOPTIC
PATTERN...EVEN DISREGARDING THE CANADIAN MODEL WHICH HAS RECENTLY
SHOWN POOR RUN TO RUN CONTINUITY. ONE INTERESTING FEATURE ON THE 00Z
GFS IS A LOW THAT DROPS OUT OF EASTERN CANADA AND MOVES WESTWARD
TOWARDS THE UPPER GREAT LAKES FRIDAY INTO SATURDAY. WHILE THE LATEST
ECMWF DOES NOT SHOW THIS AS STRONGLY...PREVIOUS RUNS HAVE DEPICTED
SUCH A FEATURE. ONE CONSISTENT FEATURE IS A 850MB HIGH OVER FAR
NORTHWEST ONTARIO WHICH COULD BRING AS COLD AS 0C AIR OVER THE UPPER
GREAT LAKES THIS WEEKEND. EASTERLY FLOW THIS COLD OVER A RELATIVELY
WARM LAKE COULD PRODUCE SOME LAKE EFFECT /RAIN/ SHOWERS...BUT WITH
QUESTIONS ABOUT THE UPPER PATTERN THROUGH THIS PERIOD CONFIDENCE
REMAINS LOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1220 PM CDT MON SEP 28 2015
VFR CONDITIONS EXPECTED THROUGH THE NEXT 24 HOURS WITH HIGH CLOUDS
STREAMING EWD ACROSS THE AREA THIS AFTERNOON AND CLEARING OUT
TONIGHT. WINDS WILL BECOME GUSTY FROM THE NW THIS AFTERNOON AROUND
15 TO 20 KTS...AND REMAIN BREEZY FROM THE N/NW TONIGHT AROUND 5
TO 10 KT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 69 40 56 37 / 10 0 0 0
INL 62 29 56 33 / 0 0 0 0
BRD 70 38 60 38 / 20 0 0 0
HYR 70 36 59 29 / 60 0 0 0
ASX 70 40 58 34 / 30 0 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
SHORT TERM...LE
LONG TERM...JJM
AVIATION...TENTINGER
AREA FORECAST DISCUSSION
NWS DULUTH MN
634 AM CDT MON SEP 28 2015
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 304 AM CDT MON SEP 28 2015
A WEAK COLD FRONT IS SLOWLY SLIDING SOUTHEAST ACROSS THE FORECAST
AREA EARLY THIS MORNING...GENERALLY DRAPED FROM LAKE SUPERIOR
SOUTHEAST ACROSS CENTRAL MINNESOTA AND ON INTO SOUTH DAKOTA. SOME
SCATTERED SHOWERS ARE AFFECTING NORTHWEST WISCONSIN OUT AHEAD OF
IT...BUT NOT BRINGING MUCH IN THE WAY OF PRECIPITATION. SOME FOG
HAS FORMED BEHIND THE FRONT...BUT VISIBILITIES ARE STILL IN THE 3-5
MILE RANGE AND DO NOT EXPECT CONDITIONS TO GET MUCH WORSE. THE
FRONT WILL CONTINUE TO SLIDE SOUTHEAST THIS MORNING...AND SHOULD BE
SOUTHEAST OF THE FORECAST AREA BY MID DAY. OF INTEREST ON SATELLITE
IMAGERY THIS MORNING IS A SHORTWAVE MOVING OUT OF WYOMING AND INTO
SOUTH DAKOTA...WITH SOME DECENTLY COLD CLOUD TOPS AND A FAIR AMOUNT
OF LIGHTNING WITH IT...SOMEWHAT UNUSUAL FOR THIS TIME OF YEAR AND
DAY. THUS...EXPECT THAT THIS PARTICULAR FEATURES IS PROBABLY
STRONGER THAN MOST OF THE MODELS SHOW...AND EXPECT IT TO CONTINUE TO
RIPPLE EAST ALONG THE COLD FRONT DURING THE DAY TODAY. BASED ON
THIS STRONGER FEATURE HAVE GONE WITH HIGHER POPS ACROSS MY
SOUTHEASTERN CWA DURING THE DAY TODAY...USING THE 06Z HRRR RUN FOR
THE GENERAL PLAN AND HAVE MADE SOME OTHER TWEAKS TO PLACE A BAND OF
SHOWERS AND ISOLATED THUNDERSTORMS ACROSS MY NW WISCONSIN COUNTIES
DURING THE DAYTIME TODAY...GENERALLY FROM 15Z TO 21Z.
OTHERWISE...IT SHOULD BE A FAIRLY DECENT DAY WITH HIGHS IN THE 60S
MOST LOCATIONS AND LIGHT WINDS. TONIGHT THE FRONT DROPS FAR ENOUGH
SOUTH THAT THE RIDGE OF HIGH PRESSURE CAN BUILD INTO THE AREA FOR
TONIGHT AND TUESDAY. THIS SHOULD SET US UP FOR A GOOD RADIATIONAL
COOLING NIGHT WITH CLEAR OR NEARLY CLEAR SKIES AND COLD TEMPERATURES
ALOFT TO ACCOMPANY THE COLD AIRMASS MOVING INTO THE AREA. LATEST
GUIDANCE INDICATES THAT WE WILL HAVE SOME 850MB TEMPS IN THE -3 C
RANGE BY 12Z. THIS SHOULD SET US UP FOR SOME CHILLY TEMPERATURES
TONIGHT...WITH LOWS DIPPING INTO EVEN THE UPPER 20S IN SOME OF OUR
COLD SPOTS AND 30S ELSEWHERE. FROST IS A REAL POSSIBILITY. HAVE
LEFT IT TO THE DAY SHIFT TO SEND OUT A FROST/FREEZE ADVISORY AS
SPECIFIC LOCATIONS ARE STILL SOMEWHAT IN QUESTION...BUT ANTICIPATE
THAT WE WILL NEED ONE OR BOTH FOR AT LEAST PARTS OF THE FORECAST
AREA. TUESDAY TO REMAIN CHILLY WITH HIGHS ONLY IN THE 50S IN THIS
CHILLY AIRMASS...AND THE DRY AIR TO BRING OUR MIN RH VALUES DOWN
INTO THE 20 PERCENT RANGE DURING THE AFTERNOON.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 304 AM CDT MON SEP 28 2015
LOW CONFIDENCE IN THE PATTERN LATE WEEK INTO THE WEEKEND DUE TO A
WIDE RANGE IN MODEL SOLUTIONS...BUT SOME NOTABLE TRENDS ARE
BEGINNING TO EMERGE. A COOL TUESDAY NIGHT WITH TEMPERATURES FALLING
TO NEAR FREEZING IN SOME LOCATIONS...THEN GENERALLY SEASONABLE
TEMPERATURES WITH LOW CHANCES FOR PRECIPITATION THROUGH THE REST OF
THE PERIOD.
ON THE SYNOPTIC SCALE THE LONG TERM PERIOD BEGINS WITH AN AMPLIFIED
RIDGE ACROSS THE INTERMOUNTAIN WEST AND BROAD TROUGH OVER THE
SOUTHEAST. AN AREA OF HIGH PRESSURE WILL BE DRIFTING EASTWARD WITH
WEST/SOUTHWEST FLOW AT LOW/MID LEVELS DEVELOPING ON WEDNESDAY. AS
THIS HIGH DEPARTS TUESDAY NIGHT TEMPS ARE EXPECTED TO FALL TO NEAR
FREEZING...MAINLY ACROSS INLAND NORTHWEST WISCONSIN BUT ALSO IN
POCKETS ACROSS THE IRON RANGE AND MN ARROWHEAD. AN EMBEDDED
SHORTWAVE TROUGH JUST AHEAD OF THE RIDGE AXIS WILL DIVE SOUTHWARD
FROM SASKATCHEWAN/MANITOBA INTO THE NORTHERN PLAINS. WHILE THE BEST
UPPER LEVEL FORCING WILL BE IN SOUTHERN MANITOBA...WITH WARM AIR
ADVECTION AND A FAIRLY DEEP LAYER OF MOISTURE IN PLACE THERE IS A
CHANCE FOR SHOWERS LATE WED/WED NIGHT ACROSS NORTHWEST TO EVEN NORTH
CENTRAL MINNESOTA...WITH THE BEST CHANCE TOWARDS THE BORDERLAND.
WHILE CLOUDS WILL BE PRESENT ACROSS MUCH OF NORTHERN MINNESOTA
WEDNESDAY...THEY SHOULD BEGIN TO CLEAR OUT THURSDAY AS EASTERLY LOW
LEVEL WINDS PREVAIL DUE TO AN 850/700 MB HIGH OVER ONTARIO.
FOR THE WEEKEND GUIDANCE IS ALL OVER THE PLACE WITH THE SYNOPTIC
PATTERN...EVEN DISREGARDING THE CANADIAN MODEL WHICH HAS RECENTLY
SHOWN POOR RUN TO RUN CONTINUITY. ONE INTERESTING FEATURE ON THE 00Z
GFS IS A LOW THAT DROPS OUT OF EASTERN CANADA AND MOVES WESTWARD
TOWARDS THE UPPER GREAT LAKES FRIDAY INTO SATURDAY. WHILE THE LATEST
ECMWF DOES NOT SHOW THIS AS STRONGLY...PREVIOUS RUNS HAVE DEPICTED
SUCH A FEATURE. ONE CONSISTENT FEATURE IS A 850MB HIGH OVER FAR
NORTHWEST ONTARIO WHICH COULD BRING AS COLD AS 0C AIR OVER THE UPPER
GREAT LAKES THIS WEEKEND. EASTERLY FLOW THIS COLD OVER A RELATIVELY
WARM LAKE COULD PRODUCE SOME LAKE EFFECT /RAIN/ SHOWERS...BUT WITH
QUESTIONS ABOUT THE UPPER PATTERN THROUGH THIS PERIOD CONFIDENCE
REMAINS LOW.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 633 AM CDT MON SEP 28 2015
EARLY THIS MORNING AREAS OF FOG ARE RESULTING IN IFR OR WORSE
CONDITIONS AT INL AND HIB...BUT THESE WILL IMPROVE RAPIDLY TOWARDS
SUNRISE. MID TO HIGH LEVEL VFR CLOUDS TODAY WITH NORTHWEST WINDS
TODAY GUSTING TO NEAR 20KTS AT TIMES IN NORTHEAST MINNESOTA. IN
NORTHWEST WISCONSIN A WEAK COLD FRONT WILL STALL OUT AND WITH AN
UPPER LEVEL DISTURBANCE MOVING IN FROM THE WEST SCATTERED SHOWERS
AND POSSIBLY A THUNDERSTORMS ARE EXPECTED. JUST WENT WITH VCSH AT
HYR FOR NOW BASED ON CURRENT RADAR AS THE BEST CHANCES FOR THUNDER
APPEAR FARTHER SOUTH. SKIES CLEAR OUT TONIGHT EVERYWHERE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 65 40 55 37 / 10 0 0 0
INL 61 30 55 33 / 0 0 0 0
BRD 67 39 59 38 / 20 0 0 0
HYR 67 37 58 29 / 60 0 0 0
ASX 68 40 57 34 / 30 0 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
SHORT TERM...LE
LONG TERM...JJM
AVIATION...JJM
AREA FORECAST DISCUSSION
NWS DULUTH MN
305 AM CDT MON SEP 28 2015
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 304 AM CDT MON SEP 28 2015
A WEAK COLD FRONT IS SLOWLY SLIDING SOUTHEAST ACROSS THE FORECAST
AREA EARLY THIS MORNING...GENERALLY DRAPED FROM LAKE SUPERIOR
SOUTHEAST ACROSS CENTRAL MINNESOTA AND ON INTO SOUTH DAKOTA. SOME
SCATTERED SHOWERS ARE AFFECTING NORTHWEST WISCONSIN OUT AHEAD OF
IT...BUT NOT BRINGING MUCH IN THE WAY OF PRECIPITATION. SOME FOG
HAS FORMED BEHIND THE FRONT...BUT VISIBILITIES ARE STILL IN THE 3-5
MILE RANGE AND DO NOT EXPECT CONDITIONS TO GET MUCH WORSE. THE
FRONT WILL CONTINUE TO SLIDE SOUTHEAST THIS MORNING...AND SHOULD BE
SOUTHEAST OF THE FORECAST AREA BY MID DAY. OF INTEREST ON SATELLITE
IMAGERY THIS MORNING IS A SHORTWAVE MOVING OUT OF WYOMING AND INTO
SOUTH DAKOTA...WITH SOME DECENTLY COLD CLOUD TOPS AND A FAIR AMOUNT
OF LIGHTNING WITH IT...SOMEWHAT UNUSUAL FOR THIS TIME OF YEAR AND
DAY. THUS...EXPECT THAT THIS PARTICULAR FEATURES IS PROBABLY
STRONGER THAN MOST OF THE MODELS SHOW...AND EXPECT IT TO CONTINUE TO
RIPPLE EAST ALONG THE COLD FRONT DURING THE DAY TODAY. BASED ON
THIS STRONGER FEATURE HAVE GONE WITH HIGHER POPS ACROSS MY
SOUTHEASTERN CWA DURING THE DAY TODAY...USING THE 06Z HRRR RUN FOR
THE GENERAL PLAN AND HAVE MADE SOME OTHER TWEAKS TO PLACE A BAND OF
SHOWERS AND ISOLATED THUNDERSTORMS ACROSS MY NW WISCONSIN COUNTIES
DURING THE DAYTIME TODAY...GENERALLY FROM 15Z TO 21Z.
OTHERWISE...IT SHOULD BE A FAIRLY DECENT DAY WITH HIGHS IN THE 60S
MOST LOCATIONS AND LIGHT WINDS. TONIGHT THE FRONT DROPS FAR ENOUGH
SOUTH THAT THE RIDGE OF HIGH PRESSURE CAN BUILD INTO THE AREA FOR
TONIGHT AND TUESDAY. THIS SHOULD SET US UP FOR A GOOD RADIATIONAL
COOLING NIGHT WITH CLEAR OR NEARLY CLEAR SKIES AND COLD TEMPERATURES
ALOFT TO ACCOMPANY THE COLD AIRMASS MOVING INTO THE AREA. LATEST
GUIDANCE INDICATES THAT WE WILL HAVE SOME 850MB TEMPS IN THE -3 C
RANGE BY 12Z. THIS SHOULD SET US UP FOR SOME CHILLY TEMPERATURES
TONIGHT...WITH LOWS DIPPING INTO EVEN THE UPPER 20S IN SOME OF OUR
COLD SPOTS AND 30S ELSEWHERE. FROST IS A REAL POSSIBILITY. HAVE
LEFT IT TO THE DAY SHIFT TO SEND OUT A FROST/FREEZE ADVISORY AS
SPECIFIC LOCATIONS ARE STILL SOMEWHAT IN QUESTION...BUT ANTICIPATE
THAT WE WILL NEED ONE OR BOTH FOR AT LEAST PARTS OF THE FORECAST
AREA. TUESDAY TO REMAIN CHILLY WITH HIGHS ONLY IN THE 50S IN THIS
CHILLY AIRMASS...AND THE DRY AIR TO BRING OUR MIN RH VALUES DOWN
INTO THE 20 PERCENT RANGE DURING THE AFTERNOON.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 304 AM CDT MON SEP 28 2015
LOW CONFIDENCE IN THE PATTERN LATE WEEK INTO THE WEEKEND DUE TO A
WIDE RANGE IN MODEL SOLUTIONS...BUT SOME NOTABLE TRENDS ARE
BEGINNING TO EMERGE. A COOL TUESDAY NIGHT WITH TEMPERATURES FALLING
TO NEAR FREEZING IN SOME LOCATIONS...THEN GENERALLY SEASONABLE
TEMPERATURES WITH LOW CHANCES FOR PRECIPITATION THROUGH THE REST OF
THE PERIOD.
ON THE SYNOPTIC SCALE THE LONG TERM PERIOD BEGINS WITH AN AMPLIFIED
RIDGE ACROSS THE INTERMOUNTAIN WEST AND BROAD TROUGH OVER THE
SOUTHEAST. AN AREA OF HIGH PRESSURE WILL BE DRIFTING EASTWARD WITH
WEST/SOUTHWEST FLOW AT LOW/MID LEVELS DEVELOPING ON WEDNESDAY. AS
THIS HIGH DEPARTS TUESDAY NIGHT TEMPS ARE EXPECTED TO FALL TO NEAR
FREEZING...MAINLY ACROSS INLAND NORTHWEST WISCONSIN BUT ALSO IN
POCKETS ACROSS THE IRON RANGE AND MN ARROWHEAD. AN EMBEDDED
SHORTWAVE TROUGH JUST AHEAD OF THE RIDGE AXIS WILL DIVE SOUTHWARD
FROM SASKATCHEWAN/MANITOBA INTO THE NORTHERN PLAINS. WHILE THE BEST
UPPER LEVEL FORCING WILL BE IN SOUTHERN MANITOBA...WITH WARM AIR
ADVECTION AND A FAIRLY DEEP LAYER OF MOISTURE IN PLACE THERE IS A
CHANCE FOR SHOWERS LATE WED/WED NIGHT ACROSS NORTHWEST TO EVEN NORTH
CENTRAL MINNESOTA...WITH THE BEST CHANCE TOWARDS THE BORDERLAND.
WHILE CLOUDS WILL BE PRESENT ACROSS MUCH OF NORTHERN MINNESOTA
WEDNESDAY...THEY SHOULD BEGIN TO CLEAR OUT THURSDAY AS EASTERLY LOW
LEVEL WINDS PREVAIL DUE TO AN 850/700 MB HIGH OVER ONTARIO.
FOR THE WEEKEND GUIDANCE IS ALL OVER THE PLACE WITH THE SYNOPTIC
PATTERN...EVEN DISREGARDING THE CANADIAN MODEL WHICH HAS RECENTLY
SHOWN POOR RUN TO RUN CONTINUITY. ONE INTERESTING FEATURE ON THE 00Z
GFS IS A LOW THAT DROPS OUT OF EASTERN CANADA AND MOVES WESTWARD
TOWARDS THE UPPER GREAT LAKES FRIDAY INTO SATURDAY. WHILE THE LATEST
ECMWF DOES NOT SHOW THIS AS STRONGLY...PREVIOUS RUNS HAVE DEPICTED
SUCH A FEATURE. ONE CONSISTENT FEATURE IS A 850MB HIGH OVER FAR
NORTHWEST ONTARIO WHICH COULD BRING AS COLD AS 0C AIR OVER THE UPPER
GREAT LAKES THIS WEEKEND. EASTERLY FLOW THIS COLD OVER A RELATIVELY
WARM LAKE COULD PRODUCE SOME LAKE EFFECT /RAIN/ SHOWERS...BUT WITH
QUESTIONS ABOUT THE UPPER PATTERN THROUGH THIS PERIOD CONFIDENCE
REMAINS LOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1233 AM CDT MON SEP 28 2015
VFR TO MVFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD...WITH AS
LOW AS IFR CONDITIONS AT INL AND HIB EARLY THIS MORNING. A WEAK
COLD FRONT WILL CONTINUE TO MOVE ACROSS THE NORTHLAND THIS
MORNING...SLOWING AS IT MOVES ACROSS NORTHWEST WISCONSIN. A FEW
SHOWERS ARE POSSIBLE ALONG AND AHEAD OF THE FRONT TONIGHT INTO
EARLY TOMORROW...BUT CONDITIONS SHOULD GENERALLY REMAIN VFR.
BEHIND THE FRONT FOG HAS DEVELOPED IN NORTHEAST MINNESOTA
INCLUDING AT HIB AND INL...AND ADDITIONAL DEVELOPMENT IS POSSIBLE
AT DLH AND BRD TOWARDS MORNING. ANOTHER NIGHT OF LOW LEVEL WIND
SHEAR FOR MOST TAF SITES AS WELL.
BY MONDAY MORNING FOG/STRATUS SHOULD DISSIPATE WITH VFR CONDITIONS
PREVAILING THROUGH THE DAY AND INTO THE EVENING WITH A LIGHT WEST
WIND.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 65 40 55 37 / 10 0 0 0
INL 61 30 55 33 / 0 0 0 0
BRD 67 39 59 38 / 20 0 0 0
HYR 67 37 58 29 / 60 0 0 0
ASX 68 40 57 34 / 30 0 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
SHORT TERM...LE
LONG TERM...JJM
AVIATION...JJM
PREVIOUS FORECAST DISCUSSION ALLUDED TO WILL HAVE TO CLOSELY WATCH
FIRE DANGER POTENTIAL IN THIS TIMEFRAME ESPECIALLY IN WESTERN AREAS
WHERE RH SHOULD BE LOWEST AND ANTECEDENT CONDITIONS ARE DRIEST.
HOWEVER...GIVEN UNCERTAINTY IN THE DETAILS OF EVOLVING E COAST LOW
PRESSURE AND ULTIMATE EFFECTS ON OUR SURFACE WINDS AND AIR
MASS...HAVE NOT PUT ANYTHING IN HWO AS OF YET. MODEL LOW LEVEL TEMP
FORECASTS SUGGEST MODEL BLENDS ARE TOO WARM FOR LATE WEEK INTO THE
WEEKEND. HOWEVER GIVEN FULL SUN AND GENERALLY DRY GROUND EXCEPT OVER
FAR EASTERN MS...AM HESITANT TO LOWER MAX TEMPS. HENCE FOR NOW JUST
EXPANDED THE DIURNAL RANGES...GOING WITH MODEL GUIDANCE FOR MAXES BUT
CUTTING 3-5 DEG FOR MINS ESPECIALLY FRI AND SAT MORNINGS. /AEG/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 70 85 69 84 / 30 36 29 32
MERIDIAN 71 83 67 83 / 40 39 37 36
VICKSBURG 70 85 67 85 / 20 40 27 24
HATTIESBURG 72 87 69 85 / 36 31 21 46
NATCHEZ 69 83 67 84 / 20 35 23 27
GREENVILLE 71 83 68 84 / 20 43 28 19
GREENWOOD 71 83 67 84 / 30 46 33 26
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
DC/26/AEG
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1016 AM CDT MON SEP 28 2015
.UPDATE...
GRIDS ADJUSTED THIS MORNING TO BUMP UP TEMPS...LOWER POPS AND ALLOW
FOR A BIT MORE SUNSHINE.
&&
.SHORT TERM...
WATER VAPOR IMAGERY THIS MORNING SHOWS A WELL DEFINED UPPER LOW OVER
SE TX SUPPORTING A BROAD S/SW FLOW IN THE MID/UPPER LEVELS ACROSS THE
GULF COAST REGION. THREE SIGNIFICANT AREAS OF CONVECTION ARE
OCCURRING IN THIS AREA: 1) CLOSE TO THE UPPER LOW OVER SE TX/SW LA
AND ADJACENT WATERS...2) OVER THE WESTERN FL PANHANDLE IN COUPLED
UPPER JET REGION BETWEEN JET MAXIMA OVER LOWER OHIO VALLEY AND
WESTERN GULF OF MEXICO...3) IN A BROAD AREA OVER THE EASTERN GULF OF
MEXICO ASSOCIATED WITH INVEST 99L. UNFORTUNATELY...FOR THOSE IN THE
ARKLAMISS WANTING/NEEDING RAIN...IT APPEARS AS THOUGH THESE AREAS
WILL REMAIN THE FOCUS FOR CONVECTIVE DEVELOPMENT TODAY.
WATER VAPOR SHOWS ANOTHER DISTURBANCE AND AREA OF ASCENT OVER THE
CENTRAL GULF LIFTING NE...BUT EXTRAPOLATION AND THE HRRR KEEPS THE
FOCUS FOR NEW DEVELOPMENT ASSOCIATED WITH THIS SYSTEM TO OUR EAST.
MORNING KJAN RAOB SHOWS THAT SIGNIFICANT DRYING HAS OCCURRED
THROUGHOUT THE COLUMN WITH PW DOWN TO ABOUT 1.6 IN...AND WATER VAPOR
IMPLIES THIS DRY AIR PARTICULARY IN MID AND UPPER LEVELS HAS
OVERSPREAD MOST OF THE FORECAST AREA. VISIBLE IMAGERY SHOWS
WIDESPREAD LOW CLOUDS ACROSS THE AREA...BUT WITH SOME BREAKS. GIVEN
DRIER AIR ALOFT AND DECENT LOW/MID LEVEL FLOW EXPECT THAT SOME MIXING
WILL CONTINUE TO ERODE BREAKS IN LOW CLOUDS AND ALLOW FOR SOME
SUN AT TIMES AND A BIT OF LIMITED DAYTIME HEATING. GIVEN THIS HAVE
ADJUSTED CLOUD COVER GRIDS DOWN A BIT FOR TODAY AND RAISED TEMPS A
FEW DEGREES. COMBO OF SOME HEATING AND DRIER AIR IN MID/UPPER LEVELS
SHOULD YIELD ENOUGH CONVECTIVE INSTABILITY FOR SCT SHRA/ISOLD TSRA
THIS AFTERNOON. HOWEVER TRENDS AND RECENT HRRR RUNS IMPLY COVERAGE
SHOULD NOT BE OVERLY IMPRESSIVE...AND HAVE HENCE LOWERED POPS EVEN A
BIT MORE THAN EARLIER FORECAST. /AEG/
&&
.AVIATION...
EXPECT THE MVFR/IFR CONDITIONS TO CONTINUE ACROSS TAF
SITES THROUGH THE PERIOD AS A LARGE AREA OF LOW PRESSURE CENTERED
OVER THE NORTHWEST GULF CONTINUES TO ROTATE MOISTURE OVER THE AREA.
OCCASIONAL SHOWERS ARE POSSIBLE ACROSS THE AREA ALSO...BUT
CONFIDENCE IN THE TIMING OF THESE SHOWERS IS LOW. THE WINDS WILL
REMAIN OUT OF THE NORTHEAST TO EAST AT 5-8KTS THROUGH THE PERIOD./15/
&&
.PREV DISCUSSION... /ISSUED 454 AM CDT MON SEP 28 2015/
DISCUSSION...
TODAY THROUGH TUESDAY NIGHT...
MODEL CONSENSUS IS THAT THE MID/UPPER LEVEL LOW WILL MEANDER
NORTHEASTWARD FROM SOUTHEAST TEXAS INTO LOUISIANA BEFORE OPENING UP
AND SHEARING OUT AS IT EVENTUALLY GETS ABSORBED BY A FRONTAL BOUNDARY
IN THE WESTERLIES. FOR NOW HOWEVER...DEEP CYCLONIC FLOW CONTINUES TO
FUNNEL IN AN IMPRESSIVE PLUME OF TROPICAL MOISTURE FROM THE WESTERN
CARIBBEAN REGION NORTHWARD TOWARD THE CENTRAL GULF COAST REGION
(PRECIPITABLE WATER APPROACHING 2.5 INCHES). PER NHC GUIDANCE...IT
APPEARS ANY HYBRID TROPICAL SYSTEM DEVELOPMENT ASSOCIATED WITH THE
MOISTURE CHANNEL WILL BE FAR ENOUGH EAST TO NOT POSE CONCERNS FOR THE
ARKLAMISS.
THE HRRR DID A GOOD JOB YESTERDAY MORNING IN SIGNALING OR THE INLAND
DEVELOPMENT OF HEAVIER CONVECTION ALONG THE I-59 CORRIDOR (KMEI
OBSERVED > 2.5 INCHES OF RAINFALL) AND HAVE FOLLOWED IT AGAIN FOR
TODAY. RECENT RUNS SUGGEST THAT THE CURRENT MESOSCALE VORTEX OVER
WESTERN AL WILL CONTINUE TO SUPPORT WIDESPREAD RAINFALL THAT COULD
IMPACT EASTERN MS OVER THE NEXT FEW HOURS...BUT ADDITIONAL RAINFALL
AND SHOWER/TSTM DEVELOPMENT IS EXPECTED TO BE SCATTERED AND HAVE CUT
BACK ON GUIDANCE POPS JUST A BIT. WEAK MID LAPSE RATES AND LIMITED
DAYTIME HEATING DUE TO EXTENSIVE CLOUD COVER WILL LIMIT OVERALL TSTM
POTENTIAL. AS THE SYSTEM BEGINS TO SHEAR OUT TUESDAY...RAIN CHANCES
SHOULD DROP OFF SIGNIFICANTLY WITH DRIER AIR MOVING INTO THE REGION.
OTHERWISE...EXPECT DAYTIME TEMPERATURES WILL CONTINUE TO BE ON THE
MILD SIDE IN THIS WETTER/CLOUDIER REGIME. /EC/
WEDNESDAY THROUGH NEXT SUNDAY...
THERE IS SOME UNCERTAINTY WITH REGARD TO THE SPECIFICS
OF HYBRID GULF LOW DEVELOPMENT IN THE GULF OF MEXICO (OR VICINITY)
IN THE COMING SEVERAL DAYS. HOWEVER...MODEL CONSENSUS IS QUITE GOOD
THAT DEVELOPMENT EITHER IN THE EASTERN GULF OF MEXICO OR JUST OFF
THE SOUTHEAST COAST WILL STRENGTHEN A BUILDING UPPER TROUGH DEEP
DOWN INTO THE EASTERN CONUS THURSDAY AND FRIDAY. SUCH A PATTERN
SHOULD HELP DRIVE A COLD FRONT THROUGH THE REGION WEDNESDAY AND PUSH
ALL BUT MINUSCULE PRECIP CHANCES EAST OF OUR REGION BY THURSDAY.
DESPITE THE LACK OF A TRULY CHILLY AIR MASS UP NORTH TO LATCH
ONTO...THE PATTERN DEFINITELY HAS A COOL LOOK AND SHOULD BRING MOST
OF THE REGION BELOW NORMAL READINGS FOR AT LEAST A FEW DAYS IN THE
LONG TERM PERIOD.
ONE CONCERN WHICH WILL BARE WATCHING IN THE COMING DAYS IS THE
POTENTIAL FOR AN ENHANCED FIRE WEATHER RISK THURSDAY AND FRIDAY OWING
TO INCREASED WINDS...RATHER LOW AFTERNOON HUMIDITY...AND THE
CONTINUED DRY STRETCH OF WEATHER IN MANY LOCATIONS. OF COURSE...IF WE
ARE FORTUNATE...THERE WILL BE WIDESPREAD SIGNIFICANT RAINS AROUND THE
AREA OVER NEXT FEW DAYS TO ALLEVIATE MUCH OF THIS CONCERN FOR
THURSDAY AND FRIDAY. DUE TO THIS FACET OF UNCERTAINTY THE HWO WILL BE
LEFT CLEAR IN THIS REGARD FOR THE TIME BEING.
BY NEXT WEEKEND THE NORTH AMERICAN CIRCULATION PATTERN SEEMS TO HOLD
MORE THAN AN AVERAGE AMOUNT OF CHAOS THAT REMAINS TO BE WORKED OUT
WITH SUFFICIENT CONFIDENCE BY NWP MODELS. REGARDLESS...POTENTIAL OF
A WARMING TREND AND SLOWLY INCREASING RAIN CHANCES IS STILL DECENT
OVER THIS STRETCH. /BB/
AVIATION...OVERALL...FLYING CONDITIONS WILL BE RATHER POOR AS WIDESPREAD
MVFR/IFR CATEGORY STRATUS WILL PREVAIL FOR MUCH OF THE FORECAST
PERIOD. A VERY MOIST AIRMASS ASSOCIATED WITH A LARGE AREA OF LOW
PRESSURE WILL PRODUCE SCATTERED SHRA WHICH COULD IMPACT ALL TAF SITES
AT SOME POINT...BUT CONFIDENCE ON EXACT TIMING IS UNUSUALLY LOW. /EC/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 79 69 83 69 / 44 41 51 29
MERIDIAN 78 68 83 67 / 63 66 51 37
VICKSBURG 84 67 84 67 / 42 40 49 27
HATTIESBURG 82 70 85 69 / 61 43 40 21
NATCHEZ 83 69 83 67 / 43 40 44 23
GREENVILLE 83 68 82 68 / 37 42 44 28
GREENWOOD 82 68 81 67 / 41 59 53 33
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
AEG/15
AREA FORECAST DISCUSSION
NWS JACKSON MS
454 AM CDT MON SEP 28 2015
.DISCUSSION...
TODAY THROUGH TUESDAY NIGHT...
MODEL CONSENSUS IS THAT THE MID/UPPER LEVEL LOW WILL MEANDER
NORTHEASTWARD FROM SOUTHEAST TEXAS INTO LOUISIANA BEFORE OPENING UP
AND SHEARING OUT AS IT EVENTUALLY GETS ABSORBED BY A FRONTAL BOUNDARY
IN THE WESTERLIES. FOR NOW HOWEVER...DEEP CYCLONIC FLOW CONTINUES TO
FUNNEL IN AN IMPRESSIVE PLUME OF TROPICAL MOISTURE FROM THE WESTERN
CARIBBEAN REGION NORTHWARD TOWARD THE CENTRAL GULF COAST REGION
(PRECIPITABLE WATER APPROACHING 2.5 INCHES). PER NHC GUIDANCE...IT
APPEARS ANY HYBRID TROPICAL SYSTEM DEVELOPMENT ASSOCIATED WITH THE
MOISTURE CHANNEL WILL BE FAR ENOUGH EAST TO NOT POSE CONCERNS FOR THE
ARKLAMISS.
THE HRRR DID A GOOD JOB YESTERDAY MORNING IN SIGNALING OR THE INLAND
DEVELOPMENT OF HEAVIER CONVECTION ALONG THE I-59 CORRIDOR (KMEI
OBSERVED > 2.5 INCHES OF RAINFALL) AND HAVE FOLLOWED IT AGAIN FOR
TODAY. RECENT RUNS SUGGEST THAT THE CURRENT MESOSCALE VORTEX OVER
WESTERN AL WILL CONTINUE TO SUPPORT WIDESPREAD RAINFALL THAT COULD
IMPACT EASTERN MS OVER THE NEXT FEW HOURS...BUT ADDITIONAL RAINFALL
AND SHOWER/TSTM DEVELOPMENT IS EXPECTED TO BE SCATTERED AND HAVE CUT
BACK ON GUIDANCE POPS JUST A BIT. WEAK MID LAPSE RATES AND LIMITED
DAYTIME HEATING DUE TO EXTENSIVE CLOUD COVER WILL LIMIT OVERALL TSTM
POTENTIAL. AS THE SYSTEM BEGINS TO SHEAR OUT TUESDAY...RAIN CHANCES
SHOULD DROP OFF SIGNIFICANTLY WITH DRIER AIR MOVING INTO THE REGION.
OTHERWISE...EXPECT DAYTIME TEMPERATURES WILL CONTINUE TO BE ON THE
MILD SIDE IN THIS WETTER/CLOUDIER REGIME. /EC/
WEDNESDAY THROUGH NEXT SUNDAY...
THERE IS SOME UNCERTAINTY WITH REGARD TO THE SPECIFICS
OF HYBRID GULF LOW DEVELOPMENT IN THE GULF OF MEXICO (OR VICINITY)
IN THE COMING SEVERAL DAYS. HOWEVER...MODEL CONSENSUS IS QUITE GOOD
THAT DEVELOPMENT EITHER IN THE EASTERN GULF OF MEXICO OR JUST OFF
THE SOUTHEAST COAST WILL STRENGTHEN A BUILDING UPPER TROUGH DEEP
DOWN INTO THE EASTERN CONUS THURSDAY AND FRIDAY. SUCH A PATTERN
SHOULD HELP DRIVE A COLD FRONT THROUGH THE REGION WEDNESDAY AND PUSH
ALL BUT MINUSCULE PRECIP CHANCES EAST OF OUR REGION BY THURSDAY.
DESPITE THE LACK OF A TRULY CHILLY AIR MASS UP NORTH TO LATCH
ONTO...THE PATTERN DEFINITELY HAS A COOL LOOK AND SHOULD BRING MOST
OF THE REGION BELOW NORMAL READINGS FOR AT LEAST A FEW DAYS IN THE
LONG TERM PERIOD.
ONE CONCERN WHICH WILL BARE WATCHING IN THE COMING DAYS IS THE
POTENTIAL FOR AN ENHANCED FIRE WEATHER RISK THURSDAY AND FRIDAY OWING
TO INCREASED WINDS...RATHER LOW AFTERNOON HUMIDITY...AND THE
CONTINUED DRY STRETCH OF WEATHER IN MANY LOCATIONS. OF COURSE...IF WE
ARE FORTUNATE...THERE WILL BE WIDESPREAD SIGNIFICANT RAINS AROUND THE
AREA OVER NEXT FEW DAYS TO ALLEVIATE MUCH OF THIS CONCERN FOR
THURSDAY AND FRIDAY. DUE TO THIS FACET OF UNCERTAINTY THE HWO WILL BE
LEFT CLEAR IN THIS REGARD FOR THE TIME BEING.
BY NEXT WEEKEND THE NORTH AMERICAN CIRCULATION PATTERN SEEMS TO HOLD
MORE THAN AN AVERAGE AMOUNT OF CHAOS THAT REMAINS TO BE WORKED OUT
WITH SUFFICIENT CONFIDENCE BY NWP MODELS. REGARDLESS...POTENTIAL OF
A WARMING TREND AND SLOWLY INCREASING RAIN CHANCES IS STILL DECENT
OVER THIS STRETCH. /BB/
&&
.AVIATION...OVERALL...FLYING CONDITIONS WILL BE RATHER POOR AS WIDESPREAD
MVFR/IFR CATEGORY STRATUS WILL PREVAIL FOR MUCH OF THE FORECAST
PERIOD. A VERY MOIST AIRMASS ASSOCIATED WITH A LARGE AREA OF LOW
PRESSURE WILL PRODUCE SCATTERED SHRA WHICH COULD IMPACT ALL TAF SITES
AT SOME POINT...BUT CONFIDENCE ON EXACT TIMING IS UNUSUALLY LOW. /EC/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 77 69 83 69 / 49 41 51 29
MERIDIAN 76 68 83 67 / 68 66 51 37
VICKSBURG 82 67 84 67 / 47 40 49 27
HATTIESBURG 80 70 85 69 / 66 43 40 21
NATCHEZ 81 69 83 67 / 48 40 44 23
GREENVILLE 81 68 82 68 / 42 42 44 28
GREENWOOD 80 68 81 67 / 46 59 53 33
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
/EC/BB/
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
700 PM CDT TUE SEP 29 2015
.SHORT TERM...(This Evening through Wednesday)
Issued at 254 PM CDT TUE SEP 29 2015
The upper level trough that was moving to the west and brought
showers to the eastern Ozarks today will begin to shift back to
the east as the upper level flow catches it and moves it east.
This will occur as a cold front approaches the region and moves
through the area into tomorrow. A few showers or and a rumble of
thunder may occur through just after midnight but will quickly
diminish behind the from.
Low stratus is expected behind the front as a cold fall like
Canadian air mass filters into the Ozarks for tomorrow morning
and through tomorrow. As a result, high temperatures tomorrow are
only expected to rise into the lower 70s even after the low
overnight stratus burns off and the comes out for tomorrow
afternoon.
.LONG TERM...(Wednesday Night through Tuesday)
Issued at 254 PM CDT TUE SEP 29 2015
The forecast for the remainder of the week will feature cooler,
more fall like weather as the upper level pattern transitions to
northwest flow aloft and additional Canadian air filters south
across the plains and into the Ozarks. This will allow afternoon
temperatures to only climb into the 60s for most areas with
overnight lows falling into the middle to upper 40s.
A short wave upper level ridge will move over the area late in
the day Saturday as a vigorous upper level low moves into the
northwestern states towards the central plains. The ridge will
lose out to the Canadian air mass keeping temperatures in the 60s
through the weekend.
The upper level low will move very slowly towards the plains with
a bit of a warming trend expected to start next week before the
low finally begins to move into the plains by the middle of next
week and bring the first good chance of rain to the Ozarks since
the beginning of September.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday Evening)
Issued at 0645 PM CDT TUE SEP 29 2015
For the KSGF/KJLN/KBBG tafs: VFR conditions to start will give
way to mvfr/ifr ceilings behind a cold front. SREF and HRRR timing
bring in the lower clouds toward 04z-06z and exit from north to
south just 1400-1800 UTC. Will continue monitor and amend as
needed for timing.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Hatch
LONG TERM...Hatch
AVIATION...DSA
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
332 PM CDT MON SEP 28 2015
.SHORT TERM: (Through Late Tonight)
Issued at 330 PM CDT Mon Sep 28 2015
Forecast area continues to get squeezed between upper level
shortwave energy that is retrograding back to the north towards
forecast area and next cold front moving in from the northwest.
Showers currently trying to move into our far southern counties as
of 20z. So will initially see isolated/scattered showers develop and
advect north into forecast area through this evening and into the
overnight hours. In the meantime, cold front will move closer to
region from the northwest, but will not see any precipitation from
it until after 12z Tuesday, just an increase in cloud cover. Because
of this weather pattern, winds will be light and variable. As for
overnight lows, once again to remain about 10 degrees above normal,
in the low to mid 60s.
Byrd
.LONG TERM: (Tuesday through Next Monday)
Issued at 330 PM CDT Mon Sep 28 2015
FA will remain on the northern fringes of the upper low drifting
into the lower Mississippi Valley tomorrow, while upper trof
pushing into the upper Great Lakes will allow cold front that
approaching northern sections of the FA late tonight to ooze
across the region during the day. Some PoPs will be tied to both
these features, but I`m really not sure that the 12z based MOS
from either the NAM or GFS have a real good handle on the expected
precip threat and/or trends.
Mass and moisture fields would certainly suggest that southeast
sections of the CWA will be on the northern fringes of the precip
associated with the southern system on Tuesday, which also suggests
that some MOS numbers in this section of the FA may be a bit too
high (and this has certainly been the case for the past several
days). However, the last few hours of the last several HRRR runs
suggest precip blossoming very late tonight as far north to near the
I44-I70 corridor...roughly near the northern trofing associated with
the upper low. I have upped PoPs some over the southeast half of
the CWA, but ultimately expect a pretty sharp PoP gradient that will
be resolved in the nowcast time frame.
Meanwhile across the north, expect a fairly large band of showers
along and especially north of the cold front just north of our FA
early Tuesday, with the showers working southeast and gradually
diminishing in coverage with time as the cold front works across the
region. Some low post-frontal shower threat will likely linger into
the evening hours before the drier air behind the front scours out
the low level moisture.
The latest 12z guidance is continuing the trend of the last few days
of being more bullish deepening the UA trof over the eastern CONUS
during the latter half of the week, which in turn allows for a
stronger intrusion of the Canadian high into the mid-Mississippi
Valley. Based on progged 850MB thermal profiles, temperatures will
have a decidely autumn feel...with highs dropping into the 60s and
lows tumbling into the 40s across the entire region Friday-Sunday.
With the high progged to exert greater dominance in the weather over
the region, it would appear that precip chances will be fairly low.
Specifics in the medium range UA progs are hard to pin down as
solutions are noisy and chaotic to say the least...but there does
seem to be some agreement that WAA will develop over the Plains
Friday night, with associated shower threat possibly working into
western/sw portions of the FA Sat-Sun.
Truett
&&
.AVIATION: (For the 18z TAFs through 18z Tuesday Afternoon)
Issued at 1228 PM CDT Mon Sep 28 2015
Diurnal mvfr cu has developed across the forecast area so will see
mvfr cigs for a few hours before lifting to low end vfr by 20z
Monday. Otherwise, light and variable winds. Cold front to move
into forecast area during the morning on Tuesday, moving through
KUIN by 14z and metro area by 17z Tuesday. Will see winds veer to
the north behind the front and pickup to between 10 and 15kts and
mvfr cigs move in. Precipitation coverage hard to pin down with
this boundary, so kept tafs dry for now. On another note, with
some low level moisture lingering, could see some patchy fog
towards daybreak on Tuesday in the river valleys, so may need to
add mention in later tafs at KSUS and KCPS.
Specifics for KSTL:
Diurnal mvfr cu has developed across the forecast area so will see
mvfr cigs for a few hours before lifting to low end vfr by 20z
Monday. Otherwise, light and variable winds. Cold front to move
into metro area by 17z Tuesday. Will see winds veer to the north
behind the front and pickup to between 10 and 15kts and mvfr cigs
move in. Precipitation coverage hard to pin down with this
boundary, so kept taf dry for now. On another note, with some low
level moisture lingering, could see some patchy fog towards
daybreak on Tuesday in the river valleys, so may need to add
mention in later tafs at KSUS and KCPS.
Byrd
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 67 81 56 73 / 20 30 20 5
Quincy 62 74 48 68 / 10 30 10 5
Columbia 62 80 52 72 / 10 30 20 5
Jefferson City 61 81 55 72 / 10 30 20 5
Salem 65 78 57 72 / 30 40 20 5
Farmington 63 76 56 71 / 30 40 20 5
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
926 PM MDT TUE SEP 29 2015
.UPDATE...
UPDATED FORECAST BECAUSE WINDOW FOR CONVECTION DEVELOPING IN
SOUTHEAST MONTANA APPEARS TO BE CLOSING AND LATEST RUC RUN
SUPPORTS THIS TREND. STILL LOOKING AT FOG DEVELOPING OVER
SOUTHEAST MONTANA BUT MAINLY OVER CARTER AND FALLON COUNTIES AND
ALONG THE YELLOWSTONE INTO CUSTER COUNTY. BORSUM
&&
.SHORT TERM...VALID FOR WED AND THU...
AT LEAST ONE DETERMINISTIC MODEL /GFS/ KEEPS A CHANCE OF SHOWERS
IN OUR EAST THIS EVENING THANKS TO A LOW LEVEL THETA-E RIDGE AXIS
NEAR THE DAKOTA BORDER. SO WILL KEEP A SLIGHT CHANCE OF
THUNDERSHOWERS IN THROUGH THE EVENING. WEDNESDAY LOOKS LIKE A
DRY...WARM DAY AHEAD OF THE APPROACHING WEATHER SYSTEM FROM THE
WEST. FLOW ALOFT BEGINS TO TRANSITION AND BACK AHEAD OF THE TROUGH
TO WHICH BRINGS SOME PACIFIC MOISTURE AND WARM ADVECTION LIFT TO
THE ABSAROKA/BEARTOOTH MOUNTAINS BY WEDNESDAY NIGHT...THOUGH I
SUSPECT THIS WILL REMAIN ISOLATED IN NATURE. BY THURSDAY...HEIGHT
FALLS/FRONTOGENESIS INDUCE LIFT ACROSS OUR REGION. WE EXPECT TO
SEE INCREASING CLOUDS AND SCATTERED SHOWERS OVER THE MOUNTAINS AND
NEARBY FOOTHILLS AS DEEPER MOISTURE RIDES INTO THE AREA ON THE
NOSE OF THE 500MB JET. THE SHOWERS SPREAD EAST THURSDAY NIGHT.
AFTERNOON TEMPERATURES SHOULD BE 5 TO 10 DEGREES COOLER THAN
WEDNESDAYS.
IT SHOULD BE NOTED...MODELS HAVE TRENDED THIS INITIAL PART OF THE
WEATHER SYSTEM FAIRLY WARM. THUS...SNOWFALL IF ANY WILL BE LIMITED
TO THE HIGHER MOUNTAIN PEAKS IN THE SHORT TERM. LOOK FOR A CHANCE
OF LOWER SNOW LEVELS BY THE WEEKEND AS OUTLINED IN THE LONG TERM
DISCUSSION. BT
.LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE...
MAIN ISSUES IN THE EXTENDED PERIOD REMAIN IN REGARD TO THE
POTENTIAL WET WEATHER COMING FRIDAY INTO THE WEEKEND. EVENT HAS
TWO PIECES...THE FIRST INVOLVING A SLOW-MOVING TROF LIFTING OUT OF
THE GREAT BASIN FRIDAY AND FRIDAY NIGHT...THE SECOND A COLDER LOW
DROPPING OUT OF WESTERN CANADA AND THROUGH THE PAC NW.
SHOWERS ARE LIKELY ACROSS MUCH OF THE AREA FRIDAY THRU FRIDAY
NIGHT AND HAVE EXPANDED LIKELY POPS ACROSS OUR AREA...THOUGH MUST
CONTINUE TO STRESS UNCERTAINTY WITH THE EXACT TRACK OF A WEAK MID
LEVEL LOW ACROSS EASTERN MT. PWATS WILL BE QUITE HIGH AT ABOUT 2
STANDARD DEVIATIONS ABOVE NORMAL...AND THERE WILL BE SOME MODEST
INSTABILITY...SO EVEN WITH WEAK FORCING SHOWERS SHOULD BE
GENERATED FAIRLY EASILY. THERE WILL BE AN UPSLOPE COMPONENT TO
THE PCPN...BUT MORE IMPORTANT ITEM TO NOTE MAY BE THE INVERTED
TROF EAST OF BILLINGS WHICH COULD BE A FOCUS FOR SHOWER
DEVELOPMENT AND IN ALL LIKELIHOOD SHOULD BE WHERE THE HEAVIER PCPN
OCCURS. IT IS ALSO WORTH NOTING THOUGH THE AIRMASS WILL BE QUITE
WARM THROUGH THE INITIAL STAGES OF THIS EVENT...WITH 700MB TEMPS A
BIT ON THE POSITIVE SIDE...SO ONLY RISK OF SNOW WILL BE OVER THE
HIGHEST PEAKS. STILL EXPECTING TOTAL PCPN TO VARY BETWEEN 0.25
AND 0.75 INCHES...BUT SOME LOCALLY HIGHER CONVECTIVE AMOUNTS COULD
DEFINITELY OCCUR ESPECIALLY OVER OUR EAST.
CONFIDENCE HAS INCREASED SATURDAY/SUNDAY AS THE GFS HAS FINALLY
SHIFTED TOWARD THE ECMWF IN SHOWING A COLDER LOW DROPPING THROUGH
THE PAC NW...IE TO OUR WEST. AGAIN...FORCING WILL BE WEAK GIVEN
SUCH A TRACK...BUT COMBINATION OF MOIST UPSLOPE FLOW AND A
LINGERING WEAK MID LEVEL LOW SOMEWHERE NEAR OUR EAST SHOULD ALLOW
FOR SHOWERS TO CONTINUE ACROSS MUCH OF OUR CWA INTO SUNDAY. A
STRONGER PUSH OF COLD ADVECTION FROM CANADA WILL ALLOW FOR SNOW
LEVELS TO DROP AND IT IS POSSIBLE WE COULD SEE A MIX WITH SNOW
SHOWERS ALONG OUR FOOTHILLS AT LOCATIONS SUCH AS RED LODGE BY
SATURDAY NIGHT. HAVE RAISED POPS INTO SUNDAY AND LOWERED TEMPS
THROUGH THE WEEKEND...AS WE SHOULD SEE HIGHS NO WARMER THAN THE
50S BY SUNDAY. SNOW WILL BE AN ISSUE OVER BEARTOOTH PASS.
FLOW ACROSS THE CONUS IS RATHER COMPLEX AND COULD BE ADDITIONALLY
ALTERED BY TROPICAL ACTIVITY IN THE WESTERN ATLANTIC. GIVEN THIS
COMPLEXITY WE WILL NEED TO CONTINUE TO MONITOR MODEL TRENDS OVER
THE COMING DAYS. ENSEMBLE TEMPERATURE SPREADS REMAIN GREAT OVER
OUR CWA THIS WEEKEND INTO EARLY NEXT WEEK.
WE SHOULD SEE SOME DRYING NEXT MONDAY AND TUESDAY BUT THERE IS
POTENTIAL FOR IMPACTS FROM RESIDUAL TROF OVER THE GREAT BASIN.
TEMPS SHOULD ALSO BEGIN TO MODERATE WITH HIGHS CLIMBING BACK INTO
THE 60S MONDAY AND PERHAPS NEAR 70F BY TUESDAY.
JKL
&&
.AVIATION...
EXPECT VFR CONDITIONS FOR MOST OF THE AREA THROUGH WED. THE
POTENTIAL EXISTS FOR SOME FOG ACROSS SOUTHEAST MT AFTER ABOUT 10Z
WED...AFFECTING KMLS AND KBHK. ANY FOG/LOW CLOUDS SHOULD LIFT BY
LATE WED MORNING. JKL/RMS
&&
.PRELIMINARY POINT TEMP/POPS...
WED THU FRI SAT SUN MON TUE
-----------------------------------------------------------
BIL 049/082 053/071 051/060 046/059 042/055 039/066 046/069
00/U 12/T 36/W 55/W 43/W 21/B 12/W
LVM 044/081 049/069 047/060 042/056 039/056 038/067 039/069
00/U 24/T 46/W 45/W 54/W 21/B 22/W
HDN 046/083 049/076 050/062 045/060 042/058 039/068 043/072
00/U 02/T 36/W 65/W 43/W 21/B 12/W
MLS 048/081 048/077 052/065 046/061 043/058 042/068 045/070
00/U 01/B 56/W 65/W 43/W 21/B 12/W
4BQ 049/083 050/078 051/066 046/060 044/059 042/069 045/070
10/U 02/T 46/W 65/W 43/W 21/B 12/W
BHK 047/080 048/075 049/062 044/058 042/058 041/067 044/068
10/U 01/B 56/W 64/W 43/W 21/B 12/W
SHR 045/083 049/077 049/062 044/060 040/058 039/069 040/070
00/U 12/T 36/W 65/W 54/W 21/B 12/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
1038 PM MDT SUN SEP 27 2015
.UPDATE...
UPDATED FORECAST LATE THIS EVENING TO SPREAD POPS TO COVER ENTIRE
FORECAST AREA THROUGH MIDNIGHT AND TO EXPAND AND ENHANCE POPS FOR
THE OVERNIGHT PERIOD. RADAR SHOWING ISOLATED TO SCATTERED SHOWERS
AND THUNDERSTORMS ACROSS THE REGION THIS EVENING. COVERAGE IS MORE
WIDESPREAD THAN MODEL FORCING WOULD SUGGEST THUS THE UPDATE. BEST
CHANCES FOR PRECIPITATION OVERNIGHT WILL BE SOUTH OF A MILES CITY
TO BILLINGS LINE AS ISENTROPIC LIFT AND RIGHT REAR QUAD JET ENERGY
COMBINE TO ENHANCE LIFT. PRECIPITATION STILL LOOKS LIGHT AT LESS
THAN A TENTH OF AN INCH IN GENERAL. CHAMBERS
&&
.SHORT TERM...VALID FOR MON AND TUE...
HEIGHTS STILL FALLING ACROSS THE AREA AS AN UPPER LEVEL TROUGH
MOVES FROM ALBERTA INTO SASKATCHEWAN. HIGH PRESSURE BUILDING INTO
NORTHERN MONTANA WITH THIS TROUGH MOVEMENT IS BRINGING EASTERLY
LOW LEVEL FLOW AND MUCH COOLER TEMPERATURES. WATER VAPOR SHOWS
MOISTURE MOVING OVER THE AREA BUT DEEPER TAP IS OVER WYOMING AND
CURRENT RADAR DOES SO ANY PRECIPITATION IS LIMITED TO THE HIGHER
TERRAIN OVER THE PARK AND THE BIG HORNS. WITH DEWPOINTS ON THE
RISE HRRR CONTINUES TO INDICATE CLOUD COVER WILL INCREASE OVER
SOUTHERN MONTANA AND LIGHT SHOWERS DEVELOPING AFTER 9 PM.
UNFORTUNATELY THIS TIMING MAY IMPACT LUNAR ECLIPSE VIEWING FOR
PEOPLE.
MONDAY IS MOSTLY DRY WITH A CONTINUED COOLING TREND WITH HEIGHTS
BUILDING WEAKLY OVER THE AREA. MONDAY NIGHT ANOTHER ROUND OF
SHOWERS BECOMES POSSIBLE FOR SOUTHERN PORTIONS OF SOUTHEAST
MONTANA AS A WEAK SHORTWAVE MOVES THROUGH THE AREA AND MOISTURE IS
PULLED INTO THAT AREA AROUND SURFACE HIGH PRESSURE OVER THE
EASTERN DAKOTAS. STILL NOT A BUNCH OF MOISTURE EXPECTED.
TUESDAY HEIGHTS BUILD UPSTREAM WITH DOWNSLOPE SURFACE FLOW
DEVELOPING. THIS WILL BRING A REBOUND IN TEMPERATURES AND DRYING
BUT NO WHERE NEAR THE SUMMERTIME CONDITIONS SEEN EARLIER THIS
WEEKEND. BORSUM
.LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN...
EXTENDED DETERMINISTIC MODELS WERE SHOWING AGREEMENT EARLY...WHILE
THE EURO ENSEMBLES CONTINUED TO SHOW UNCERTAINTY WITH THE PATTERN
THROUGH THE PERIOD...AND THE GEFS SHOWED GOOD AGREEMENT UNTIL 00Z
FRI. NOTED THAT DETERMINISTIC MODELS START FALLING OUT OF
AGREEMENT ON FRI WITH POTENTIALLY POTENT APPROACHING WEST-COAST
SYSTEM.
UPPER RIDGING SHOULD DOMINATE THROUGH THURSDAY AFTERNOON... TO
THEN BE REPLACED BY PACIFIC TROUGH WHEN MODEL QPF BEGINS TO
INCREASE WITH ASSOCIATED FORCING IN WESTERN ZONES. THE TROUGH WILL
FORM AN UPPER LOW THAT SHIFTS SE DURING FRI... WITH TRENDING
RAINFALL ACCUMULATIONS IN THE SAME DIRECTION. ISOLATED TO
SCATTERED POPS ARE PRESENT IN THE GRIDS TO COVER THIS CHANCE OF
SHOWERS AND THUNDERSTORMS OVER MOST THE AREA ON THURSDAY THROUGH
FRIDAY AFTERNOON. CURRENT SOUTHERN EXTENT OF TRACK SHOULD BRING
COOLER WEATHER INTO THE AREA GRADUALLY... AS THE FRONTAL COMPLEX
AND SFC LOW ALSO REMAINS FURTHER SOUTH.
GFS SOLUTION HAS MID-LEVEL TEMPS AND QPF IN FAVOR OF AT LEAST
SOME MOUNTAIN SNOWFALL THROUGH SUNDAY AFTERNOON BUT EURO IS
SIGNIFICANTLY WARMER AND DRIER IN THE SAME PERIOD. THIS SOLUTION
BRINGS AN UPPER LOW ONTO THE CENTRAL CA COST...WHILE THE GFS HAD
THE LOW NEARBY BUT MUCH WEAKER..WITH DOWNSTREAM RIDGING IN THE
EURO LIKELY THE SOURCE OF WARMER TEMPS. BOTH MODELS THUS HAD VERY
DIFFERENT VERSIONS OF FLOW OVER THE REGION BY THE END OF THE
PERIOD...WITH SW IN THE EURO AND SOME WEAK CYCLONIC CURVATURE IN
THE NW FLOW FROM THE GFS... BUT THE REST OF THE PERIOD WAS DRY IN
BOTH MODELS. MROWELL
&&
.AVIATION...
ISOLATED TO SCATTERED SHOWERS WILL IMPACT AREAS ALONG AND SOUTH/
EAST OF A KLVM-KBIL-KMLS LINE TONIGHT. VFR SHOULD PREVAIL AT LOWER
ELEVATIONS BUT THE BEARTOOTH/ABSAROKA AND BIGHORN MOUNTAINS WILL
BE OCCASIONALLY OBSCURED. SHOWERS WILL TAPER OFF FROM WEST TO EAST
LATE TONIGHT. IT WILL BE DRY WITH VFR CONDITIONS ACROSS THE AREA ON
MONDAY. JKL
&&
.PRELIMINARY POINT TEMP/POPS...
MON TUE WED THU FRI SAT SUN
-----------------------------------------------------------
BIL 049/068 046/078 051/081 053/072 051/065 047/059 041/063
20/B 00/U 01/U 35/W 53/W 22/W 11/B
LVM 041/069 042/078 046/081 048/068 046/064 044/058 039/062
20/U 00/U 01/B 34/W 32/W 22/W 22/W
HDN 047/070 044/079 048/084 050/076 048/067 045/062 041/068
30/B 01/B 11/U 35/W 52/W 22/W 11/B
MLS 049/068 044/077 048/081 052/077 050/066 046/063 042/066
21/B 01/B 11/U 25/W 43/W 22/W 11/B
4BQ 050/066 046/077 049/082 051/076 049/067 046/064 043/068
41/E 01/B 21/U 13/W 54/W 22/W 21/B
BHK 047/064 043/072 047/078 049/073 048/064 044/062 041/064
32/W 01/B 21/U 23/W 44/W 21/B 11/B
SHR 046/069 043/079 047/082 048/075 048/067 042/063 039/068
31/B 11/B 11/B 24/W 33/W 22/W 11/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
322 PM CDT MON SEP 28 2015
.SYNOPSIS...
ISSUED AT 320 PM CDT MON SEP 28 2015
LARGE UPPER LOW OVER THE HUDSON BAY REGION WITH SEVERAL PV
ANOMALIES ROTATING AROUND IT. IN ADDITION...POSITIVELY TILTED
UPPER LOW OVER THE E PAC WITH AN UPPER LEVEL PV CONNECTION TO THE
UPPER LOW OVER THE HUDSON BAY. CLOSER TO HOME...WEAKER PV ANOMALY
MOVING ACROSS SRN WY ATTM GENERATING SHRA AND ISOLD TSRA ACROSS
ERN WY...WITH ISOLD SHRA/-TSRA IN PORTIONS OF NC NEBR ASSOCIATED
WITH WEAKENING MID LEVEL FGEN ACROSS THAT AREA. SFC FRONTAL
BOUNDARY NEARLY STALLED FROM NEAR LIMON CO TO NORTH OF GLD TO JUST
S OF EAR TO S OF YANKTON SD.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 320 PM CDT MON SEP 28 2015
NEW COLD FRONTAL BOUNDARY WILL SLOWLY PUSH SWD OVERNIGHT WITH
MOST OF WESTERN AND NC NEBR REMAINING IN THE POST FRONTAL UPSLOPE
FLOW LATE TONIGHT INTO EARLY TUESDAY. THIS WILL BE ATTENDANT TO A
EWD ADVANCING PV ANOMALY AS MENTIONED WHICH WILL MOVE ACROSS SRN
SD/NRN NEBR THROUGH THE NIGHT. SOME MID LEVEL INSTABILITY PRESENT
OVERNIGHT BUT UNCERTAINTY IN COVERAGE AREA AS ISENTROPIC LIFT
REMAINS PRESENT ON THE 305/310K LEVELS. ELEVATED WEAK TSRA
DEVELOPMENT IN THE LAST HOUR ACROSS BROWN...ROCK AND HOLT COUNTIES
STILL ASSOCIATED WITH MID LEVEL FGEN WITHIN AN AREA OF MID LEVEL
INSTABILITY. INTEGRATING THE VARIOUS SOLUTIONS OVERNIGHT YIELDS AN
AREA OF SHRA AND TSRA CURRENTLY OVER SWRN SD TO MOVE ACROSS NRN
NEBR BUT THEN SOME MODELS SUGGEST AN AREA OF MID LEVEL FGEN ACROSS
CENTRAL NEBRASKA IN THE 06- 09Z TIME FRAME THAT MAY ALLOW
REDEVELOPMENT WWD. MEANWHILE THE HRRR SUGGESTS DEVELOPMENT WITH
THE SWD ADVANCING FRONT PRIOR TO 06Z AND THEN PUSHING SEWD
OVERNIGHT. WITH SEVERAL SMALL SHORT WAVES MOVING THROUGH THE AREA
TIMING AND LOCATION OF NEW DEVELOPMENT BECOMES DIFFICULT. HAVE
THEREFORE INCLUDED CHANCE POPS MOST LOCATIONS THROUGH THE NIGHT.
IN ADDITION TO THE PRECIP...LOW LEVEL UPSLOPE FLOW SHOULD ALLOW
FOR DEVELOPMENT OF STRATUS AND AT LEAST PATCHY FOG AFTER
MIDNIGHT...THOUGH WINDS ARE CURRENTLY STRONGER THAN WOULD BE
FAVORABLE FOR WIDESPREAD LOW VSBYS. HENCE HAVE SIDED ON PATCHY FOG
MENTION.
ISENTROPIC LIFT CONTINUES OFF AND ON THROUGHOUT THE DAY TUESDAY SO
WOULD EXPECT OCCASIONAL REDEVELOPMENT OF SHRA ESPECIALLY IN SWRN
NEBR. TEMPS WILL BE HELD DOWN CONSIDERABLY DUE TO LOW CLOUD COVER
AND ANY PRECIP THAT DOES DEVELOP.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 320 PM CDT MON SEP 28 2015
MODELS AGAIN COMING IN COOLER. HAVE USED A BLEND OF THE GFS AND
NAM FOR THE MID TERM AND GFS AND ECMWF FOR THE LONG TERM. TOMORROW
NIGHT UPSLOPE FLOW THROUGH THE PANHANDLE AND SOUTHWEST NEBRASKA
WITH A STATIONARY BOUNDARY TO THE WEST SEVERAL WEAK WAVES MOVING
THROUGH RIDGE. ISOLATED THUNDER ALONG THE BOUNDARY WITH LLJ AND
SOME LIFT. ISOLATED RAINSHOWERS CONTINUING THROUGH THE MORNING
WITH DRIZZLE TO THE EAST LATE AFTERNOON INTO THE EVENING. COOLER
AIR FILTERING INTO WESTERN NEBRASKA THURSDAY NIGHT THROUGH THE
WEEKEND. ECMWF WARMER THAN GFS. STRONG WAVE MOVING OUT OF THE
ROCKIES WITH SHARP GRADIENT OVER THE NEBRASKA PANHANDLE. COOL AT
THE SURFACE WITH INSTABILITY ALOFT AS WARNER AIR AT THE SURFACE TO
THE SOUTH LIFTED OVER THE COOLER AIR. STRONG LOW LEVEL JET OVER
NIGHT WITH THUNDERSTORMS LIKELY. TRANSITIONING TO RAINSHOWERS
THROUGH THE DAY ON FRIDAY AND CONTINUING THROUGH SATURDAY NIGHT AS
UPPER LOW MOVES EAST AND BECOMES NEGATIVELY TILTED. SHOWERS END
SUNDAY WITH A WARMUP INTO MONDAY. TEMPERATURES IN THE 60S EAST AND
70S WEST WEDNESDAY AND THURSDAY AND THEN COOLER AIR FOR FRIDAY AND
SATURDAY WITH TEMPERATURES IN THE 50S. 50S AND 60S SUNDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 109 PM CDT MON SEP 28 2015
VFR CONDITIONS ARE EXPECTED TO PREVAIL ACROSS THE KLBF AND KVTN
TERMINALS UP UNTIL THE 06Z HOUR...HOWEVER...RAIN SHOWERS WILL BE
POSSIBLE THROUGH THE 23Z-04Z WHICH COULD LOWER CEILINGS TEMPORARILY
TO MVFR. THESE RAIN SHOWERS WILL BE SUPPORTED BY WEAK UPPER LEVEL
FORCING AND A SLOWLY SAGGING COLD FRONT ACROSS WESTERN AND NORTH
CENTRAL NEBRASKA...WHICH IS REPRESENTED FAIRLY WELL BY CURRENT SHORT
TERM MODELS. WINDS PRIOR TO THE 06Z HOUR...ESPECIALLY WITHIN THE
KLBF TERMINAL...WILL BE BREEZY FROM THE NORTHEAST. THE FORECAST
AFTER 06Z THEN BECOMES TRICKY...AS VARYING SOLUTIONS ARE CURRENTLY
BEING PROPOSED BY THE NAM/GFS/RAP/SREF MODELS. THE MAJOR
UNCERTAINTY THAT ARISES FROM THE VARYING MODELING SOLUTIONS IS BOTH
AREAL COVERAGE OF THE LOWER CEILINGS...IN ADDITION TO THE MAGNITUDE
OF THE LOWER CEILINGS. THE CURRENT 12Z NAM SOLUTION IS THE MOST
AGGRESSIVE IN AREAL COVERAGE AND MAGNITUDE OF THE LOWER CEILINGS...
THE 12Z GFS IS THEN CONSIDERABLY DRIER IN NATURE...WITH THE RAP
BEING A MIDDLE OF THE ROAD SOLUTION WITH RESPECT TO THESE CEILINGS.
HAVE DECIDED TO SIDE WITH THE NAM SOLUTION WITH RESPECT TO THE KLBF
TERMINAL AFTER 06Z...AS THE KLBF TERMINAL WILL BE IN CLOSEST
PROXIMITY TO THE COLD FRONT. HAVE THEN SIDED WITH MORE OF A GFS/RAP
SOLUTION FOR KVTN...AS THE AFOREMENTIONED COLD FRONT WILL BE
DISPLACED FAR ENOUGH TO THE SOUTH...LIMITING THE AMOUNT OF STRATUS.
AT THIS TIME...NOT THINKING THAT FOG WILL BE A PROBLEM AT EITHER THE
KLBF AND KVTN TERMINALS...AS WINDS WILL REMAIN ABOVE MINIMUM
THRESHOLDS CONDUCIVE TO THE FORMATION OF FOG.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JWS
SHORT TERM...JWS
LONG TERM...POWER
AVIATION...MOLDAN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
135 PM EDT MON SEP 28 2015
.SYNOPSIS...
SHOWERS WILL BE POSSIBLE TODAY, MAINLY OVER THE FINGER LAKES AND
CENTRAL NEW YORK. SHOWERS WILL BECOME MORE LIKELY ON TUESDAY INTO
WEDNESDAY, AS A COLD FRONT PUSHES INTO THE REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
1130 AM UPDATE...
THE CURRENT FORECAST FOR THIS AFTERNOON INTO THE EVENING STILL
LOOKS REASONABLE, WITH JUST MINOR TWEAKS REQUIRED AT THIS TIME.
SCATTERED SHOWERS WILL CONTINUE TO BE SEEN OVER OUR WESTERN AND
NORTHERN ZONES, AS THE BEST MOISTURE FEED IS IN THIS AREA, AROUND
THE OUTER PERIPHERY OF THE SLOWLY DEPARTING LOW-LEVEL RIDGE.
LITTLE OR NO PRECIPITATION IS ANTICIPATED OVER THE NEAR-TERM,
ALONG AND EAST OF THE I-81 CORRIDOR.
DESPITE ABUNDANT CLOUD COVER, A MILD AIR MASS, ALONG WITH FURTHER
LOW-LEVEL WARM ADVECTION, WILL STILL BRING HIGHS INTO THE 70S OVER
MANY AREAS THIS AFTERNOON.
PREVIOUS DISCUSSION... 400 AM UPDATE...
AFTER GETTING LUCKY FOR MOST OF THE AREA LAST NIGHT BEING CLEAR
ENOUGH TO VIEW THE ECLIPSE, REALITY IS SETTING IN WITH THICK
CLOUDS ON OUR DOORSTEPS WITH SOME SHOWERS NOT FAR BEHIND. FOLLOWED
LATEST HRRR QPF FIELDS AND INCREASED TO LIKELY POPS THROUGH MID
MORNING FROM THE WESTERN SOUTHERN TIER UP THROUGH FINGER LAKES.
PRECIP SHOULD MAKE IT TO CNY BUT MAY BREAK UP A BIT BY THE TIME
THAT HAPPENS. LATER TODAY AND THROUGH TONIGHT RAIN CHANCES DON`T
LOOK ALL THAT GREAT BUT WE CAN`T RULE ANYTHING OUT, ESPECIALLY IN
PRETTY MUCH THE SAME AREAS JUST MENTIONED ABOVE. FARTHER SOUTH
ESPECIALLY INTO PA, MAINLY DRY WEATHER IS EXPECTED.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
4 AM UPDATE...
ALTHOUGH MY GARDEN IS WINDING DOWN DUE TO THE LOSS OF DAYLIGHT/LOW
SUN ANGLE, I AM GETTING EXCITED ABOUT THE POSSIBILITY OF SOME
RAIN AROUND HERE! RAIN CHANCES GO UP FOR OUR AREA BY TUESDAY
AFTERNOON AS A COLD FRONT APPROACHES. CONTINUE TO MENTION SOME
ISOLATED THUNDER THROUGH EARLY TUESDAY NIGHT TO MATCH WELL WITH
OTHER OFFICES ALONG WITH THE FACT LI`S ARE NEAR OR BELOW ZERO.
UNLIKE PAST RAIN EVENTS WITH EACH MODEL RUN WE ARE LOOKING AT
INCREASING CHANCES FOR HIGHER RAINFALL AMOUNTS INSTEAD OF LOWER
ONES. IN FACT THE MAIN TREND OF THE 0Z RUNS OF BOTH THE EURO AND
GFS NOT ONLY RAISE RAINFALL AMOUNTS, THE PROGRESSION OF THE COLD
FRONT THROUGH OUR AREA IS MUCH SLOWER. ACCORDINGLY I RAISED POPS
ABOVE 70% FOR THE ENTIRE AREA TUESDAY NIGHT. IN FACT THROUGH MUCH
OF WEDNESDAY NOW, WE HAVE POPS ABOVE 60% FROM NEAR BINGHAMTON
SOUTH AND EAST. DRIER WEATHER NOW HOLDS OFF UNTIL WED NIGHT. AT
EARLY LOOK AT TOTAL RAINFALL AMOUNTS WOULD BE A HALF OF AN INCH UP
ACROSS THE FINGER LAKES, BUT EXCEEDING AN INCH FROM NEAR
BINGHAMTON SOUTH AND EAST, WHERE PRECIP LINGERS THE LONGEST.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
200 PM SUNDAY UPDATE...
THOUGH DIFFERING ON DETAILS...MODELS ARE STARTING TO GET INTO
BETTER LARGE SCALE AGREEMENT...ON THE IDEA OF AN UNSETTLED TROUGHY
PATTERN TAKING SHAPE BY NEXT WEEKEND. ONSHORE FLOW...CUTOFF LOW
EVOLUTION...AS WELL AS POTENTIAL COASTAL SURFACE LOW...MAY ALLOW
MOISTURE TO START CREEPING IN AS EARLY AS FRIDAY AFTERNOON-
NIGHT...BUT THE END RESULT DOES APPEAR TO BE COOL AND WET PERIODS
INTO NEXT WEEKEND. BEFORE THEN...MAINLY DRY WITH TEMPERATURES
SLIGHTLY BELOW CLIMATOLOGY THANKS TO FEED OF AIR FROM SURFACE
HIGH PRESSURE IN QUEBEC. A FRONTAL ZONE WILL BE STALLED OUT NOT
TOO FAR SOUTHEAST OF US...SO THAT WILL NEED TO BE MONITORED...BUT
KEEPING FORECAST GENERALLY DRY FOR NOW WEDNESDAY NIGHT THROUGH
THURSDAY NIGHT.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
MARINE LAYER WITH LOW LEVEL S/SE FLOW WILL CONTINUE TO RESULT IN FAIRLY
LOW CIGS THROUGH THE TAF PERIOD. CIGS GENERALLY RISE TO LOW END
VFR THIS AFTERNOON BUT THEN DROP AGAIN TO MVFR THIS EVENING. LATE
TONIGHT INTO TUESDAY MORNING IFR WILL EVEN BE POSSIBLE AT
TIMES...ESPECIALLY FOR KITH/KBGM/KAVP. NOT EXPECTING MUCH OF A
RISE IN CIGS FOR TUESDAY WITH SHOWERS MOVING IN BY MID TO LATE
MORNING AND HEAVIER PRECIP ARRIVING BEYOND THE TAF PERIOD.
EXPECT WINDS GENERALLY S/SE AROUND 5 TO 10 KNOTS THROUGH THE TAF
PERIOD.
.OUTLOOK...
TUES AFT-TUES NGT...SHOWERS, HEAVY AT TIMES, WITH ASSOCIATED
RESTRICTIONS.
WEDNESDAY...CONTINUING SHOWERS AND ASSOCIATED RESTRICTIONS LIKELY.
THURSDAY - SATURDAY...BRIEF RESPITE IN UNSETTLED CONDITIONS
POSSIBLE THURSDAY BEFORE MORE RAIN/SHOWERS AND ASSOCIATED
RESTRICTIONS ARRIVE BY LATE FRIDAY INTO SATURDAY.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN/MLJ
SHORT TERM...HEDEN
LONG TERM...MDP
AVIATION...PCF
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1135 AM EDT MON SEP 28 2015
.SYNOPSIS...
SHOWERS WILL BE POSSIBLE TODAY, MAINLY OVER THE FINGER LAKES AND
CENTRAL NEW YORK. SHOWERS WILL BECOME MORE LIKELY ON TUESDAY INTO
WEDNESDAY, AS A COLD FRONT PUSHES INTO THE REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
1130 AM UPDATE...
THE CURRENT FORECAST FOR THIS AFTERNOON INTO THE EVENING STILL
LOOKS REASONABLE, WITH JUST MINOR TWEAKS REQUIRED AT THIS TIME.
SCATTERED SHOWERS WILL CONTINUE TO BE SEEN OVER OUR WESTERN AND
NORTHERN ZONES, AS THE BEST MOISTURE FEED IS IN THIS AREA, AROUND
THE OUTER PERIPHERY OF THE SLOWLY DEPARTING LOW-LEVEL RIDGE.
LITTLE OR NO PRECIPITATION IS ANTICIPATED OVER THE NEAR-TERM,
ALONG AND EAST OF THE I-81 CORRIDOR.
DESPITE ABUNDANT CLOUD COVER, A MILD AIR MASS, ALONG WITH FURTHER
LOW-LEVEL WARM ADVECTION, WILL STILL BRING HIGHS INTO THE 70S OVER
MANY AREAS THIS AFTERNOON.
PREVIOUS DISCUSSION... 400 AM UPDATE...
AFTER GETTING LUCKY FOR MOST OF THE AREA LAST NIGHT BEING CLEAR
ENOUGH TO VIEW THE ECLIPSE, REALITY IS SETTING IN WITH THICK
CLOUDS ON OUR DOORSTEPS WITH SOME SHOWERS NOT FAR BEHIND. FOLLOWED
LATEST HRRR QPF FIELDS AND INCREASED TO LIKELY POPS THROUGH MID
MORNING FROM THE WESTERN SOUTHERN TIER UP THROUGH FINGER LAKES.
PRECIP SHOULD MAKE IT TO CNY BUT MAY BREAK UP A BIT BY THE TIME
THAT HAPPENS. LATER TODAY AND THROUGH TONIGHT RAIN CHANCES DON`T
LOOK ALL THAT GREAT BUT WE CAN`T RULE ANYTHING OUT, ESPECIALLY IN
PRETTY MUCH THE SAME AREAS JUST MENTIONED ABOVE. FARTHER SOUTH
ESPECIALLY INTO PA, MAINLY DRY WEATHER IS EXPECTED.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
4 AM UPDATE...
ALTHOUGH MY GARDEN IS WINDING DOWN DUE TO THE LOSS OF DAYLIGHT/LOW
SUN ANGLE, I AM GETTING EXCITED ABOUT THE POSSIBILITY OF SOME
RAIN AROUND HERE! RAIN CHANCES GO UP FOR OUR AREA BY TUESDAY
AFTERNOON AS A COLD FRONT APPROACHES. CONTINUE TO MENTION SOME
ISOLATED THUNDER THROUGH EARLY TUESDAY NIGHT TO MATCH WELL WITH
OTHER OFFICES ALONG WITH THE FACT LI`S ARE NEAR OR BELOW ZERO.
UNLIKE PAST RAIN EVENTS WITH EACH MODEL RUN WE ARE LOOKING AT
INCREASING CHANCES FOR HIGHER RAINFALL AMOUNTS INSTEAD OF LOWER
ONES. IN FACT THE MAIN TREND OF THE 0Z RUNS OF BOTH THE EURO AND
GFS NOT ONLY RAISE RAINFALL AMOUNTS, THE PROGRESSION OF THE COLD
FRONT THROUGH OUR AREA IS MUCH SLOWER. ACCORDINGLY I RAISED POPS
ABOVE 70% FOR THE ENTIRE AREA TUESDAY NIGHT. IN FACT THROUGH MUCH
OF WEDNESDAY NOW, WE HAVE POPS ABOVE 60% FROM NEAR BINGHAMTON
SOUTH AND EAST. DRIER WEATHER NOW HOLDS OFF UNTIL WED NIGHT. AT
EARLY LOOK AT TOTAL RAINFALL AMOUNTS WOULD BE A HALF OF AN INCH UP
ACROSS THE FINGER LAKES, BUT EXCEEDING AN INCH FROM NEAR
BINGHAMTON SOUTH AND EAST, WHERE PRECIP LINGERS THE LONGEST.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
200 PM SUNDAY UPDATE...
THOUGH DIFFERING ON DETAILS...MODELS ARE STARTING TO GET INTO
BETTER LARGE SCALE AGREEMENT...ON THE IDEA OF AN UNSETTLED TROUGHY
PATTERN TAKING SHAPE BY NEXT WEEKEND. ONSHORE FLOW...CUTOFF LOW
EVOLUTION...AS WELL AS POTENTIAL COASTAL SURFACE LOW...MAY ALLOW
MOISTURE TO START CREEPING IN AS EARLY AS FRIDAY AFTERNOON-
NIGHT...BUT THE END RESULT DOES APPEAR TO BE COOL AND WET PERIODS
INTO NEXT WEEKEND. BEFORE THEN...MAINLY DRY WITH TEMPERATURES
SLIGHTLY BELOW CLIMATOLOGY THANKS TO FEED OF AIR FROM SURFACE
HIGH PRESSURE IN QUEBEC. A FRONTAL ZONE WILL BE STALLED OUT NOT
TOO FAR SOUTHEAST OF US...SO THAT WILL NEED TO BE MONITORED...BUT
KEEPING FORECAST GENERALLY DRY FOR NOW WEDNESDAY NIGHT THROUGH
THURSDAY NIGHT.
&&
.AVIATION /16Z MONDAY THROUGH FRIDAY/...
UPR WV GENERATE SOME LGT SHWRS THIS MRNG OVER THE ERN SITES WHILE
LL MARINE MOISTURE CIRCULATES ARND THE NEW ENG HIPRES. THIS WILL
RESULT IN A MVFR CIG OVER MUCH OF THE AREA...WHILE OCNL SHWRS DO
NOT RESULT IN VSBY RESTRICTIONS. HTG SHD ALLOW VFR CIGS TO RETURN
TO THE AREA IN THE LATE MRNG...WHILE THE WV PASSES LTR IN THE DAY
BRINGING THE SHWRS WITH IT. LTR TNGT...MARINE LYR RETURNS THE
MVFR CIGS TO MOST STATIONS. SLY OR SELY FLOW CONTS THRU THE PD.
.OUTLOOK...
TUES-TUES NGT...CHC -SHRA AND ASSOCIATED RESTRICTIONS. BEST
CHANCE WITH FRONTAL PASSAGE TUE-TUE NGT.
WEDNESDAY-FRIDAY...MAINLY VFR EXCEPT FOR LOCAL RESTRICTIONS DUE
TO VALLEY FOG /MAINLY KELM/.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN/MLJ
SHORT TERM...HEDEN
LONG TERM...MDP
AVIATION...DGM
AREA FORECAST DISCUSSION
NWS BUFFALO NY
943 AM EDT MON SEP 28 2015
.SYNOPSIS...
A SOUTHERLY FLOW OF MOIST AIR WILL BRING SCATTERED SHOWERS TO
THE ENTIRE REGION TODAY. MORE WIDESPREAD SHOWERS WILL MOVE INTO
THE AREA TUESDAY WITH THE APPROACH OF A COLD FRONT. MUCH COOLER
AND DRIER AIR WILL ARRIVE WEDNESDAY BEHIND THE FRONT AND LAST
THROUGH THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AN INCREASINGLY MOIST AIR MASS WILL FED INTO OUR REGION FROM THE
OHIO VALLEY AND MID ATLANTIC STATES TODAY. AN AREA OF SCATTERED
SHOWERS WILL PUSH ACROSS THE AREA TODAY AS A SUBTLE MID LEVEL
VORTICITY MAXIMA MOVES NORTHWARD AND INCREASES LARGE SCALE ASCENT.
LATEST HRRR QPF FIELDS SUGGESTING THAT THE BULK OF THE SHOWER
ACTIVITY WILL OCCUR DURING THE FIRST HALF OF THE DAY AS THE UPPER
SUPPORT CROSSES THE REGION FOLLOWED BY A DIMINISHING TREND THIS
AFTERNOON AND TONIGHT.
THE INCOMING WARMER AIRMASS WILL ALLOW HIGHS TO REACH THE LOWER TO
MID 70S ON THE LAKE PLAINS TODAY WITH AN ADDED BOOST FROM A
FAVORABLE DOWNSLOPE FLOW. THE HIGHER TERRAIN OF THE SOUTHERN TIER
WILL STAY IN THE MID TO UPPER 60S WITH THICKER...LOWER CLOUD COVER.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
LATEST GUIDANCE CONTINUES TO SHOW A SURFACE FRONT CROSSING THE
REGION TUESDAY AND TUESDAY NIGHT. CURRENT FORECAST LOOKS GOOD AND
WILL MAKE NO CHANGES. PREVIOUS DISCUSSION...
A PLUME OF DEEP ATLANTIC MOISTURE CHARACTERIZED BY PRECIPITABLE
WATER VALUES NEAR 1.5IN /MORE THAN 2SD ABOVE NORMAL/ WILL LIE ACROSS
NEW YORK STATE INTO TUESDAY. THIS MOISTURE WILL BE CIRCULATING
AROUND A HIGH PRESSURE CENTER OFF THE NEW ENGLAND COAST WHILE A
BROAD 500MB TROUGH AND SURFACE COLD FRONT APPROACH FROM THE WESTERN
GREAT LAKES.
A COMBINATION OF SURFACE MOISTURE CONVERGENCE AND SERIES OF UPPER
LEVEL VORTICITY MAXIMA EXITING THE BASE OF THE 500MB TROUGH WILL
LIKELY CONTRIBUTE TO SEVERAL ROUNDS OF HIT AND MISS SHOWERS AND
EXTENSIVE CLOUD COVER INTO TUESDAY AHEAD OF THE APPROACHING COLD
FRONT. INSTABILITY AND SHEAR ARE FORECAST TO INCREASE TUESDAY
AFTERNOON WITH CAPE VALUES RISING OVER 1000 J/KG AND BULK SHEAR OF
30-35 KTS. THIS SHOULD PROMOTE SOME THUNDERSTORM ACTIVITY AHEAD OF
AND ALONG THE COLD FRONT AS IT IS FORECAST TO CROSS WESTERN AND
CENTRAL NEW YORK TUESDAY AFTERNOON AND EVENING.
THE HIGH MOISTURE AIRMASS WILL KEEP MILD TEMPERATURES IN PLACE WITH
HIGHS ON TUESDAY INTO THE 70S WITH A BREEZY SOUTHERLY FLOW AHEAD OF
THE COLD FRONT. DOWNSLOPING ACROSS THE ONTARIO LAKE PLAINS AND
GENESEE RIVER VALLEY SHOULD SUPPORT MID 70S IN THESE WARMER
LOCATIONS.
A BROAD CANADIAN SURFACE HIGH WILL BUILD IN BEHIND THE COLD FRONT
TUESDAY NIGHT THROUGH THE END OF THE WEEK. THIS WILL BRING A PUNCH
OF DRY CONTINENTAL POLAR AIR SOUTH ACROSS THE GREAT LAKES CLEARING
SKIES AND KNOCKING BACK TEMPERATURES TO MORE SEASONABLE LEVELS. THE
INITIAL SURGE OF COLD ADVECTION RIGHT BEHIND THE FRONT WILL MIX
GUSTY WINDS OF 20-30 MPH TO THE SURFACE OVERNIGHT TUESDAY INTO
WEDNESDAY AND THE NORTHERLY FLOW ACROSS LAKE ONTARIO MAY LINGER LOW
CLOUDS ACROSS WESTERN NEW YORK WITH CLEARING FIRST EAST OF LAKE
ONTARIO. TEMPERATURES WILL FEEL MORE FALL-LIKE WEDNESDAY WITH HIGHS
ONLY RISING INTO THE UPPER 50S TO LOWER 60S WITH DEWPOINTS SLIPPING
BACK TO AROUND 40. LOWS WEDNESDAY NIGHT WILL SLIP TO THE MID TO
UPPER 40S FOR LOWER ELEVATIONS AND URBAN AREAS...WITH LOW 40S TO
UPPER 30S ACROSS HIGHER TERRAIN OF THE SOUTHERN TIER AND ACROSS THE
EASTERN LAKE ONTARIO REGION.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
BROAD SURFACE HIGH PRESSURE WILL BE FOUND ACROSS THE GREAT LAKES AND
EASTERN CANADA THROUGH THE END OF THE WEEK WHILE SPLIT SUBTROPICAL
AND POLAR JETS DIG STACKED TROUGHS ACROSS EASTERN NORTH AMERICA.
THIS PATTERN WILL KEEP SEASONABLY COOL AND DRY WEATHER IN PLACE
ACROSS WESTERN AND NORTH CENTRAL NEW YORK THURSDAY AND FRIDAY.
12Z ECMWF AND GFS MODELS SHOW VASTLY DIFFERENT SOLUTIONS FOR THE
WEATHER NEXT WEEKEND WITH BOTH MODELS SHOWING CUT OFF LOWS
DEVELOPING. THE EC LOW JUST NORTH OF THE EASTERN GREAT LAKES KEEPS
ATLANTIC MOISTURE EAST AND NORTH OF THE FORECAST AREA LEAVING
WESTERN AND CENTRAL NEW YORK COOL BUT MAINLY DRY WHILE THE GFS LOW
OVER THE SOUTHEAST STATES WOULD ADVECT DEEP ATLANTIC MOISTURE NORTH
ACROSS OUR REGION WHICH WOULD YIELD WETTER AND WARMER WEATHER. THERE
IS A LOT OF ROOM AND TIME FOR MODELS TO BECOME BETTER ALIGNED FOR
NEXT WEEKEND SO JUST INCLUDED A SLIGHT CHANCE OF SHOWERS FOR NOW.
HIGH TEMPERATURES THROUGH THE LONG TERM PERIOD LOOK TO ONLY TOP OUT
AROUND 60 WITH COOL OVERNIGHT LOWS DIPPING INTO THE 40S.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
MID LEVEL WAVE LIFTING UP FROM THE OHIO VALLEY GENERATING SHOWERS
ACROSS THE AREA THIS MORNING. THIS HAS RESULTED IN DETERIORATING
CONDITIONS WITH IFR VSBYS/CIGS AT KJHW AND MVFR CIGS AT KIAG.
WHILE IFR CONDITIONS ARE ONLY EXPECTED ALONG THE SOUTHERN
TIER...CONDITIONS WILL LIKELY REMAIN OR LOWER TO MVFR AS THE
SHOWERS MOVE THROUGH THIS MORNING.
VFR CONDITIONS SHOULD RETURN THIS AFTERNOON AND TONIGHT AS THE
WAVE EXITS AND THE SHOWER ACTIVITY DIMINISHES.
OUTLOOK...
TUESDAY...VFR/MVFR WITH SHOWERS LIKELY AND POSSIBLY A
THUNDERSTORM.
WEDNESDAY THROUGH FRIDAY...VFR.
&&
.MARINE...
SOUTHERLY WINDS MOSTLY IN THE 10 TO 15 KNOT RANGE WILL CONTINUE
TODAY...THROUGH AT LEAST THE FIRST PART OF TUESDAY AS HIGH
PRESSURE WILL BE LARGELY ANCHORED OFF THE NEW ENGLAND COAST. WHILE
SOME AREAS OVER THE OPEN WATERS OF BOTH LAKES WILL SEE WINDS
INCREASING TO THE 15-20 KNOT RANGE FOR A PERIOD TODAY...THE
RESULTANT HIGHER WAVES WILL PREDOMINANTLY REMAIN OVER CANADIAN
WATERS.
AFTER THAT...A COLD FRONT WILL THEN CROSS THE LOWER LAKES TUESDAY
AFTERNOON AND EVENING. INCREASING NORTHERLIES BEHIND THIS FRONT
WILL LIKELY BRING A ROUND OF ADVISORY CONDITIONS TO BOTH LAKES
FOR THE MIDDLE OF THE WEEK.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TMA
NEAR TERM...TMA
SHORT TERM...FRANKLIN/WCH
LONG TERM...SMITH
AVIATION...TMA
MARINE...TMA
AREA FORECAST DISCUSSION
NWS BUFFALO NY
725 AM EDT MON SEP 28 2015
.SYNOPSIS...
A SOUTHERLY FLOW OF MOIST AIR WILL BRING SCATTERED SHOWERS TO
THE ENTIRE REGION TODAY. MORE WIDESPREAD SHOWERS WILL MOVE INTO
THE AREA TUESDAY WITH THE APPROACH OF A COLD FRONT. MUCH COOLER
AND DRIER AIR WILL ARRIVE WEDNESDAY BEHIND THE FRONT AND LAST
THROUGH THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AN INCREASINGLY MOIST AIR MASS WILL FED INTO OUR REGION FROM THE
OHIO VALLEY AND MID ATLANTIC STATES TODAY. AN AREA OF SCATTERED
SHOWERS WILL PUSH ACROSS THE AREA TODAY AS A SUBTLE MID LEVEL
VORTICITY MAXIMA MOVES NORTHWARD AND INCREASES LARGE SCALE ASCENT.
LATEST HRRR QPF FIELDS SUGGESTING THAT THE BULK OF THE SHOWER
ACTIVITY WILL OCCUR DURING THE FIRST HALF OF THE DAY AS THE UPPER
SUPPORT CROSSES THE REGION FOLLOWED BY A DIMINISHING TREND THIS
AFTERNOON AND TONIGHT.
THE INCOMING WARMER AIRMASS WILL ALLOW HIGHS TO REACH THE LOWER TO
MID 70S ON THE LAKE PLAINS TODAY WITH AN ADDED BOOST FROM A
FAVORABLE DOWNSLOPE FLOW. THE HIGHER TERRAIN OF THE SOUTHERN TIER
WILL STAY IN THE MID TO UPPER 60S WITH THICKER...LOWER CLOUD COVER.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
A PLUME OF DEEP ATLANTIC MOISTURE CHARACTERIZED BY PRECIPITABLE
WATER VALUES NEAR 1.5IN /MORE THAN 2SD ABOVE NORMAL/ WILL LIE ACROSS
NEW YORK STATE INTO TUESDAY. THIS MOISTURE WILL BE CIRCULATING
AROUND A HIGH PRESSURE CENTER OFF THE NEW ENGLAND COAST WHILE A
BROAD 500MB TROUGH AND SURFACE COLD FRONT APPROACH FROM THE WESTERN
GREAT LAKES.
A COMBINATION OF SURFACE MOISTURE CONVERGENCE AND SERIES OF UPPER
LEVEL VORTICITY MAXIMA EXITING THE BASE OF THE 500MB TROUGH WILL
LIKELY CONTRIBUTE TO SEVERAL ROUNDS OF HIT AND MISS SHOWERS AND
EXTENSIVE CLOUD COVER INTO TUESDAY AHEAD OF THE APPROACHING COLD
FRONT. INSTABILITY AND SHEAR ARE FORECAST TO INCREASE TUESDAY
AFTERNOON WITH CAPE VALUES RISING OVER 1000 J/KG AND BULK SHEAR OF
30-35 KTS. THIS SHOULD PROMOTE SOME THUNDERSTORM ACTIVITY AHEAD OF
AND ALONG THE COLD FRONT AS IT IS FORECAST TO CROSS WESTERN AND
CENTRAL NEW YORK TUESDAY AFTERNOON AND EVENING.
THE HIGH MOISTURE AIRMASS WILL KEEP MILD TEMPERATURES IN PLACE WITH
HIGHS ON TUESDAY INTO THE 70S WITH A BREEZY SOUTHERLY FLOW AHEAD OF
THE COLD FRONT. DOWNSLOPING ACROSS THE ONTARIO LAKE PLAINS AND
GENESEE RIVER VALLEY SHOULD SUPPORT MID 70S IN THESE WARMER
LOCATIONS.
A BROAD CANADIAN SURFACE HIGH WILL BUILD IN BEHIND THE COLD FRONT
TUESDAY NIGHT THROUGH THE END OF THE WEEK. THIS WILL BRING A PUNCH
OF DRY CONTINENTAL POLAR AIR SOUTH ACROSS THE GREAT LAKES CLEARING
SKIES AND KNOCKING BACK TEMPERATURES TO MORE SEASONABLE LEVELS. THE
INITIAL SURGE OF COLD ADVECTION RIGHT BEHIND THE FRONT WILL MIX
GUSTY WINDS OF 20-30 MPH TO THE SURFACE OVERNIGHT TUESDAY INTO
WEDNESDAY AND THE NORTHERLY FLOW ACROSS LAKE ONTARIO MAY LINGER LOW
CLOUDS ACROSS WESTERN NEW YORK WITH CLEARING FIRST EAST OF LAKE
ONTARIO. TEMPERATURES WILL FEEL MORE FALL-LIKE WEDNESDAY WITH HIGHS
ONLY RISING INTO THE UPPER 50S TO LOWER 60S WITH DEWPOINTS SLIPPING
BACK TO AROUND 40. LOWS WEDNESDAY NIGHT WILL SLIP TO THE MID TO
UPPER 40S FOR LOWER ELEVATIONS AND URBAN AREAS...WITH LOW 40S TO
UPPER 30S ACROSS HIGHER TERRAIN OF THE SOUTHERN TIER AND ACROSS THE
EASTERN LAKE ONTARIO REGION.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
BROAD SURFACE HIGH PRESSURE WILL BE FOUND ACROSS THE GREAT LAKES AND
EASTERN CANADA THROUGH THE END OF THE WEEK WHILE SPLIT SUBTROPICAL
AND POLAR JETS DIG STACKED TROUGHS ACROSS EASTERN NORTH AMERICA.
THIS PATTERN WILL KEEP SEASONABLY COOL AND DRY WEATHER IN PLACE
ACROSS WESTERN AND NORTH CENTRAL NEW YORK THURSDAY AND FRIDAY.
12Z ECMWF AND GFS MODELS SHOW VASTLY DIFFERENT SOLUTIONS FOR THE
WEATHER NEXT WEEKEND WITH BOTH MODELS SHOWING CUT OFF LOWS
DEVELOPING. THE EC LOW JUST NORTH OF THE EASTERN GREAT LAKES KEEPS
ATLANTIC MOISTURE EAST AND NORTH OF THE FORECAST AREA LEAVING
WESTERN AND CENTRAL NEW YORK COOL BUT MAINLY DRY WHILE THE GFS LOW
OVER THE SOUTHEAST STATES WOULD ADVECT DEEP ATLANTIC MOISTURE NORTH
ACROSS OUR REGION WHICH WOULD YIELD WETTER AND WARMER WEATHER. THERE
IS A LOT OF ROOM AND TIME FOR MODELS TO BECOME BETTER ALIGNED FOR
NEXT WEEKEND SO JUST INCLUDED A SLIGHT CHANCE OF SHOWERS FOR NOW.
HIGH TEMPERATURES THROUGH THE LONG TERM PERIOD LOOK TO ONLY TOP OUT
AROUND 60 WITH COOL OVERNIGHT LOWS DIPPING INTO THE 40S.
&&
.AVIATION /11Z MONDAY THROUGH FRIDAY/...
MID LEVEL WAVE LIFTING UP FROM THE OHIO VALLEY GENERATING SHOWERS
ACROSS THE AREA THIS MORNING. THIS HAS RESULTED IN DETERIORATING
CONDITIONS WITH IFR VSBYS/CIGS AT KJHW AND MVFR CIGS AT KIAG.
WHILE IFR CONDITIONS ARE ONLY EXPECTED ALONG THE SOUTHERN
TIER...CONDITIONS WILL LIKELY REMAIN OR LOWER TO MVFR AS THE
SHOWERS MOVE THROUGH THIS MORNING.
VFR CONDITIONS SHOULD RETURN THIS AFTERNOON AND TONIGHT AS THE
WAVE EXITS AND THE SHOWER ACTIVITY DIMINISHES.
OUTLOOK...
TUESDAY...VFR/MVFR WITH SHOWERS LIKELY AND POSSIBLY A
THUNDERSTORM.
WEDNESDAY THROUGH FRIDAY...VFR.
&&
.MARINE...
SOUTHERLY WINDS MOSTLY IN THE 10 TO 15 KNOT RANGE WILL CONTINUE
TODAY...THROUGH AT LEAST THE FIRST PART OF TUESDAY AS HIGH
PRESSURE WILL BE LARGELY ANCHORED OFF THE NEW ENGLAND COAST. WHILE
SOME AREAS OVER THE OPEN WATERS OF BOTH LAKES WILL SEE WINDS
INCREASING TO THE 15-20 KNOT RANGE FOR A PERIOD TODAY...THE
RESULTANT HIGHER WAVES WILL PREDOMINANTLY REMAIN OVER CANADIAN
WATERS.
AFTER THAT...A COLD FRONT WILL THEN CROSS THE LOWER LAKES TUESDAY
AFTERNOON AND EVENING. INCREASING NORTHERLIES BEHIND THIS FRONT
WILL LIKELY BRING A ROUND OF ADVISORY CONDITIONS TO BOTH LAKES
FOR THE MIDDLE OF THE WEEK.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TMA
NEAR TERM...TMA
SHORT TERM...WCH
LONG TERM...SMITH
AVIATION...TMA
MARINE...TMA
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
646 AM EDT MON SEP 28 2015
.SYNOPSIS...
SHOWERS WILL BE POSSIBLE TODAY, MAINLY OVER THE FINGER LAKES AND
CENTRAL NEW YORK. SHOWERS WILL BECOME MORE LIKELY ON TUESDAY INTO
WEDNESDAY, AS A COLD FRONT PUSHES INTO THE REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
400 AM UPDATE...
AFTER GETTING LUCKY FOR MOST OF THE AREA LAST NIGHT BEING CLEAR
ENOUGH TO VIEW THE ECLIPSE, REALITY IS SETTING IN WITH THICK
CLOUDS ON OUR DOORSTEPS WITH SOME SHOWERS NOT FAR BEHIND. FOLLOWED
LATEST HRRR QPF FIELDS AND INCREASED TO LIKELY POPS THROUGH MID
MORNING FROM THE WESTERN SOUTHERN TIER UP THROUGH FINGER LAKES.
PRECIP SHOULD MAKE IT TO CNY BUT MAY BREAK UP A BIT BY THE TIME
THAT HAPPENS. LATER TODAY AND THROUGH TONIGHT RAIN CHANCES DON`T
LOOK ALL THAT GREAT BUT WE CAN`T RULE ANYTHING OUT, ESPECIALLY IN
PRETTY MUCH THE SAME AREAS JUST MENTIONED ABOVE. FARTHER SOUTH
ESPECIALLY INTO PA, MAINLY DRY WEATHER IS EXPECTED.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
4 AM UPDATE...
ALTHOUGH MY GARDEN IS WINDING DOWN DUE TO THE LOSS OF DAYLIGHT/LOW
SUN ANGLE, I AM GETTING EXCITED ABOUT THE POSSIBILITY OF SOME
RAIN AROUND HERE! RAIN CHANCES GO UP FOR OUR AREA BY TUESDAY
AFTERNOON AS A COLD FRONT APPROACHES. CONTINUE TO MENTION SOME
ISOLATED THUNDER THROUGH EARLY TUESDAY NIGHT TO MATCH WELL WITH
OTHER OFFICES ALONG WITH THE FACT LI`S ARE NEAR OR BELOW ZERO.
UNLIKE PAST RAIN EVENTS WITH EACH MODEL RUN WE ARE LOOKING AT
INCREASING CHANCES FOR HIGHER RAINFALL AMOUNTS INSTEAD OF LOWER
ONES. IN FACT THE MAIN TREND OF THE 0Z RUNS OF BOTH THE EURO AND
GFS NOT ONLY RAISE RAINFALL AMOUNTS, THE PROGRESSION OF THE COLD
FRONT THROUGH OUR AREA IS MUCH SLOWER. ACCORDINGLY I RAISED POPS
ABOVE 70% FOR THE ENTIRE AREA TUESDAY NIGHT. IN FACT THROUGH MUCH
OF WEDNESDAY NOW, WE HAVE POPS ABOVE 60% FROM NEAR BINGHAMTON
SOUTH AND EAST. DRIER WEATHER NOW HOLDS OFF UNTIL WED NIGHT. AT
EARLY LOOK AT TOTAL RAINFALL AMOUNTS WOULD BE A HALF OF AN INCH UP
ACROSS THE FINGER LAKES, BUT EXCEEDING AN INCH FROM NEAR
BINGHAMTON SOUTH AND EAST, WHERE PRECIP LINGERS THE LONGEST.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
200 PM SUNDAY UPDATE...
THOUGH DIFFERING ON DETAILS...MODELS ARE STARTING TO GET INTO
BETTER LARGE SCALE AGREEMENT...ON THE IDEA OF AN UNSETTLED TROUGHY
PATTERN TAKING SHAPE BY NEXT WEEKEND. ONSHORE FLOW...CUTOFF LOW
EVOLUTION...AS WELL AS POTENTIAL COASTAL SURFACE LOW...MAY ALLOW
MOISTURE TO START CREEPING IN AS EARLY AS FRIDAY AFTERNOON-
NIGHT...BUT THE END RESULT DOES APPEAR TO BE COOL AND WET PERIODS
INTO NEXT WEEKEND. BEFORE THEN...MAINLY DRY WITH TEMPERATURES
SLIGHTLY BELOW CLIMATOLOGY THANKS TO FEED OF AIR FROM SURFACE
HIGH PRESSURE IN QUEBEC. A FRONTAL ZONE WILL BE STALLED OUT NOT
TOO FAR SOUTHEAST OF US...SO THAT WILL NEED TO BE MONITORED...BUT
KEEPING FORECAST GENERALLY DRY FOR NOW WEDNESDAY NIGHT THROUGH
THURSDAY NIGHT.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
UPR WV GENERATE SOME LGT SHWRS THIS MRNG OVER THE ERN SITES WHILE
LL MARINE MOISTURE CIRCULATES ARND THE NEW ENG HIPRES. THIS WILL
RESULT IN A MVFR CIG OVER MUCH OF THE AREA...WHILE OCNL SHWRS DO
NOT RESULT IN VSBY RESTRICTIONS. HTG SHD ALLOW VFR CIGS TO RETURN
TO THE AREA IN THE LATE MRNG...WHILE THE WV PASSES LTR IN THE DAY
BRINGING THE SHWRS WITH IT. LTR TNGT...MARINE LYR RETURNSRETURNING
THE MVFR CIGS TO MOST STATIONS. SLY OR SELY FLOW CONTS THRU THE
PD.
.OUTLOOK...
TUES-TUES NGT...CHC -SHRA AND ASSOCIATED RESTRICTIONS. BEST
CHANCE WITH FRONTAL PASSAGE TUE-TUE NGT.
WEDNESDAY-FRIDAY...MAINLY VFR EXCEPT FOR LOCAL RESTRICTIONS DUE
TO VALLEY FOG /MAINLY KELM/.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN
SHORT TERM...HEDEN
LONG TERM...MDP
AVIATION...DGM
AREA FORECAST DISCUSSION
NWS BUFFALO NY
445 AM EDT MON SEP 28 2015
.SYNOPSIS...
A SOUTHERLY FLOW OF MOIST AIR WILL BRING SCATTERED SHOWERS TO
THE ENTIRE REGION TODAY. MORE WIDESPREAD SHOWERS WILL MOVE INTO
THE AREA TUESDAY WITH THE APPROACH OF A COLD FRONT. MUCH COOLER
AND DRIER AIR WILL ARRIVE WEDNESDAY BEHIND THE FRONT AND LAST
THROUGH THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AN INCREASINGLY MOIST AIR MASS WILL FED INTO OUR REGION FROM THE
OHIO VALLEY AND MID ATLANTIC STATES TODAY. AN AREA OF SCATTERED
SHOWERS WILL PUSH ACROSS THE AREA TODAY AS A SUBTLE MID LEVEL
VORTICITY MAXIMA MOVES NORTHWARD AND INCREASES LARGE SCALE ASCENT.
LATEST HRRR QPF FIELDS SUGGESTING THAT THE BULK OF THE SHOWER
ACTIVITY WILL OCCUR DURING THE FIRST HALF OF THE DAY AS THE UPPER
SUPPORT CROSSES THE REGION FOLLOWED BY A DIMINISHING TREND THIS
AFTERNOON AND TONIGHT.
THE INCOMING WARMER AIRMASS WILL ALLOW HIGHS TO REACH THE LOWER TO
MID 70S ON THE LAKE PLAINS TODAY WITH AN ADDED BOOST FROM A
FAVORABLE DOWNSLOPE FLOW. THE HIGHER TERRAIN OF THE SOUTHERN TIER
WILL STAY IN THE MID TO UPPER 60S WITH THICKER...LOWER CLOUD COVER.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
A PLUME OF DEEP ATLANTIC MOISTURE CHARACTERIZED BY PRECIPITABLE
WATER VALUES NEAR 1.5IN /MORE THAN 2SD ABOVE NORMAL/ WILL LIE ACROSS
NEW YORK STATE INTO TUESDAY. THIS MOISTURE WILL BE CIRCULATING
AROUND A HIGH PRESSURE CENTER OFF THE NEW ENGLAND COAST WHILE A
BROAD 500MB TROUGH AND SURFACE COLD FRONT APPROACH FROM THE WESTERN
GREAT LAKES.
A COMBINATION OF SURFACE MOISTURE CONVERGENCE AND SERIES OF UPPER
LEVEL VORTICITY MAXIMA EXITING THE BASE OF THE 500MB TROUGH WILL
LIKELY CONTRIBUTE TO SEVERAL ROUNDS OF HIT AND MISS SHOWERS AND
EXTENSIVE CLOUD COVER INTO TUESDAY AHEAD OF THE APPROACHING COLD
FRONT. INSTABILITY AND SHEAR ARE FORECAST TO INCREASE TUESDAY
AFTERNOON WITH CAPE VALUES RISING OVER 1000 J/KG AND BULK SHEAR OF
30-35 KTS. THIS SHOULD PROMOTE SOME THUNDERSTORM ACTIVITY AHEAD OF
AND ALONG THE COLD FRONT AS IT IS FORECAST TO CROSS WESTERN AND
CENTRAL NEW YORK TUESDAY AFTERNOON AND EVENING.
THE HIGH MOISTURE AIRMASS WILL KEEP MILD TEMPERATURES IN PLACE WITH
HIGHS ON TUESDAY INTO THE 70S WITH A BREEZY SOUTHERLY FLOW AHEAD OF
THE COLD FRONT. DOWNSLOPING ACROSS THE ONTARIO LAKE PLAINS AND
GENESEE RIVER VALLEY SHOULD SUPPORT MID 70S IN THESE WARMER
LOCATIONS.
A BROAD CANADIAN SURFACE HIGH WILL BUILD IN BEHIND THE COLD FRONT
TUESDAY NIGHT THROUGH THE END OF THE WEEK. THIS WILL BRING A PUNCH
OF DRY CONTINENTAL POLAR AIR SOUTH ACROSS THE GREAT LAKES CLEARING
SKIES AND KNOCKING BACK TEMPERATURES TO MORE SEASONABLE LEVELS. THE
INITIAL SURGE OF COLD ADVECTION RIGHT BEHIND THE FRONT WILL MIX
GUSTY WINDS OF 20-30 MPH TO THE SURFACE OVERNIGHT TUESDAY INTO
WEDNESDAY AND THE NORTHERLY FLOW ACROSS LAKE ONTARIO MAY LINGER LOW
CLOUDS ACROSS WESTERN NEW YORK WITH CLEARING FIRST EAST OF LAKE
ONTARIO. TEMPERATURES WILL FEEL MORE FALL-LIKE WEDNESDAY WITH HIGHS
ONLY RISING INTO THE UPPER 50S TO LOWER 60S WITH DEWPOINTS SLIPPING
BACK TO AROUND 40. LOWS WEDNESDAY NIGHT WILL SLIP TO THE MID TO
UPPER 40S FOR LOWER ELEVATIONS AND URBAN AREAS...WITH LOW 40S TO
UPPER 30S ACROSS HIGHER TERRAIN OF THE SOUTHERN TIER AND ACROSS THE
EASTERN LAKE ONTARIO REGION.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
BROAD SURFACE HIGH PRESSURE WILL BE FOUND ACROSS THE GREAT LAKES AND
EASTERN CANADA THROUGH THE END OF THE WEEK WHILE SPLIT SUBTROPICAL
AND POLAR JETS DIG STACKED TROUGHS ACROSS EASTERN NORTH AMERICA.
THIS PATTERN WILL KEEP SEASONABLY COOL AND DRY WEATHER IN PLACE
ACROSS WESTERN AND NORTH CENTRAL NEW YORK THURSDAY AND FRIDAY.
12Z ECMWF AND GFS MODELS SHOW VASTLY DIFFERENT SOLUTIONS FOR THE
WEATHER NEXT WEEKEND WITH BOTH MODELS SHOWING CUT OFF LOWS
DEVELOPING. THE EC LOW JUST NORTH OF THE EASTERN GREAT LAKES KEEPS
ATLANTIC MOISTURE EAST AND NORTH OF THE FORECAST AREA LEAVING
WESTERN AND CENTRAL NEW YORK COOL BUT MAINLY DRY WHILE THE GFS LOW
OVER THE SOUTHEAST STATES WOULD ADVECT DEEP ATLANTIC MOISTURE NORTH
ACROSS OUR REGION WHICH WOULD YIELD WETTER AND WARMER WEATHER. THERE
IS A LOT OF ROOM AND TIME FOR MODELS TO BECOME BETTER ALIGNED FOR
NEXT WEEKEND SO JUST INCLUDED A SLIGHT CHANCE OF SHOWERS FOR NOW.
HIGH TEMPERATURES THROUGH THE LONG TERM PERIOD LOOK TO ONLY TOP OUT
AROUND 60 WITH COOL OVERNIGHT LOWS DIPPING INTO THE 40S.
&&
.AVIATION /09Z MONDAY THROUGH FRIDAY/...
EARLY THIS MORNING...INCREASING MOISTURE WILL BE ADVECTED INTO
OUR REGION FROM THE OHIO VALLEY AND MID ATLANTIC STATES. THIS WILL
RESULT IN INCREASING/THICKENING CLOUDS FROM SOUTHWEST TO
NORTHEAST...WITH SCATTERED SHOWERS ACROSS FAR WESTERN NEW YORK
WITH THE ARRIVAL OF DEEPER MOISTURE AND A WEAK MID LEVEL
SHORTWAVE. LATER TODAY...SKIES WILL REMAIN MOSTLY CLOUDY...WHILE
THE SCATTERED SHOWERS OVERSPREAD THE REMAINDER OF THE REGION.
IN TERMS OF CIGS...ACROSS THE LOWER ELEVATIONS THESE WILL DEVELOP
AND LOWER THROUGH THE VFR RANGE THIS MORNING...THOUGH WILL LIKELY
NOT DROP BELOW THAT DUE TO THE PREVAILING SOUTHERLY DOWNSLOPE FLOW
AT THE LOWER LEVELS. ACROSS THE HIGHER TERRAIN...INCREASING LOW
LEVEL MOISTURE SHOULD LEAD TO THE DEVELOPMENT OF MVFR CIGS
WHICH SHOULD PERSIST THROUGH A GOOD CHUNK OF TODAY...WITH SOME
IFR CIGS NOT OUT OF THE QUESTION THIS MORNING. AS FOR
VSBYS...WITH THE SHOWER ACTIVITY EXPECTED TO REMAIN ON THE LIGHT
AND SCATTERED SIDE...EXPECT THESE TO LARGELY REMAIN VFR THROUGH
THE PERIOD.
OUTLOOK...
TUESDAY...VFR/MVFR WITH SHOWERS LIKELY AND POSSIBLY A THUNDERSTORM.
WEDNESDAY THROUGH FRIDAY...VFR.
&&
.MARINE...
SOUTHERLY WINDS MOSTLY IN THE 10 TO 15 KNOT RANGE WILL CONTINUE
TODAY...THROUGH AT LEAST THE FIRST PART OF TUESDAY AS HIGH
PRESSURE WILL BE LARGELY ANCHORED OFF THE NEW ENGLAND COAST. WHILE
SOME AREAS OVER THE OPEN WATERS OF BOTH LAKES WILL SEE WINDS
INCREASING TO THE 15-20 KNOT RANGE FOR A PERIOD TODAY...THE
RESULTANT HIGHER WAVES WILL PREDOMINANTLY REMAIN OVER CANADIAN
WATERS.
AFTER THAT...A COLD FRONT WILL THEN CROSS THE LOWER LAKES TUESDAY
AFTERNOON AND EVENING. INCREASING NORTHERLIES BEHIND THIS FRONT
WILL LIKELY BRING A ROUND OF ADVISORY CONDITIONS TO BOTH LAKES
FOR THE MIDDLE OF THE WEEK.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TMA
NEAR TERM...TMA
SHORT TERM...WCH
LONG TERM...SMITH
AVIATION...HITCHCOCK/JJR/TMA
MARINE...TMA
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
419 AM EDT MON SEP 28 2015
.SYNOPSIS...
SHOWERS WILL BE POSSIBLE TODAY, MAINLY OVER THE FINGER LAKES AND
CENTRAL NEW YORK. SHOWERS WILL BECOME MORE LIKELY ON TUESDAY INTO
WEDNESDAY, AS A COLD FRONT PUSHES INTO THE REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
400 AM UPDATE...
AFTER GETTING LUCKY FOR MOST OF THE AREA LAST NIGHT BEING CLEAR
ENOUGH TO VIEW THE ECLIPSE, REALITY IS SETTING IN WITH THICK
CLOUDS ON OUR DOORSTEPS WITH SOME SHOWERS NOT FAR BEHIND. FOLLOWED
LATEST HRRR QPF FIELDS AND INCREASED TO LIKELY POPS THROUGH MID
MORNING FROM THE WESTERN SOUTHERN TIER UP THROUGH FINGER LAKES.
PRECIP SHOULD MAKE IT TO CNY BUT MAY BREAK UP A BIT BY THE TIME
THAT HAPPENS. LATER TODAY AND THROUGH TONIGHT RAIN CHANCES DON`T
LOOK ALL THAT GREAT BUT WE CAN`T RULE ANYTHING OUT, ESPECIALLY IN
PRETTY MUCH THE SAME AREAS JUST MENTIONED ABOVE. FARTHER SOUTH
ESPECIALLY INTO PA, MAINLY DRY WEATHER IS EXPECTED.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
4 AM UPDATE...
ALTHOUGH MY GARDEN IS WINDING DOWN DUE TO THE LOSS OF DAYLIGHT/LOW
SUN ANGLE, I AM GETTING EXCITED ABOUT THE POSSIBILITY OF SOME
RAIN AROUND HERE! RAIN CHANCES GO UP FOR OUR AREA BY TUESDAY
AFTERNOON AS A COLD FRONT APPROACHES. CONTINUE TO MENTION SOME
ISOLATED THUNDER THROUGH EARLY TUESDAY NIGHT TO MATCH WELL WITH
OTHER OFFICES ALONG WITH THE FACT LI`S ARE NEAR OR BELOW ZERO.
UNLIKE PAST RAIN EVENTS WITH EACH MODEL RUN WE ARE LOOKING AT
INCREASING CHANCES FOR HIGHER RAINFALL AMOUNTS INSTEAD OF LOWER
ONES. IN FACT THE MAIN TREND OF THE 0Z RUNS OF BOTH THE EURO AND
GFS NOT ONLY RAISE RAINFALL AMOUNTS, THE PROGRESSION OF THE COLD
FRONT THROUGH OUR AREA IS MUCH SLOWER. ACCORDINGLY I RAISED POPS
ABOVE 70% FOR THE ENTIRE AREA TUESDAY NIGHT. IN FACT THROUGH MUCH
OF WEDNESDAY NOW, WE HAVE POPS ABOVE 60% FROM NEAR BINGHAMTON
SOUTH AND EAST. DRIER WEATHER NOW HOLDS OFF UNTIL WED NIGHT. AT
EARLY LOOK AT TOTAL RAINFALL AMOUNTS WOULD BE A HALF OF AN INCH UP
ACROSS THE FINGER LAKES, BUT EXCEEDING AN INCH FROM NEAR
BINGHAMTON SOUTH AND EAST, WHERE PRECIP LINGERS THE LONGEST.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
200 PM SUNDAY UPDATE...
THOUGH DIFFERING ON DETAILS...MODELS ARE STARTING TO GET INTO
BETTER LARGE SCALE AGREEMENT...ON THE IDEA OF AN UNSETTLED TROUGHY
PATTERN TAKING SHAPE BY NEXT WEEKEND. ONSHORE FLOW...CUTOFF LOW
EVOLUTION...AS WELL AS POTENTIAL COASTAL SURFACE LOW...MAY ALLOW
MOISTURE TO START CREEPING IN AS EARLY AS FRIDAY AFTERNOON-
NIGHT...BUT THE END RESULT DOES APPEAR TO BE COOL AND WET PERIODS
INTO NEXT WEEKEND. BEFORE THEN...MAINLY DRY WITH TEMPERATURES
SLIGHTLY BELOW CLIMATOLOGY THANKS TO FEED OF AIR FROM SURFACE
HIGH PRESSURE IN QUEBEC. A FRONTAL ZONE WILL BE STALLED OUT NOT
TOO FAR SOUTHEAST OF US...SO THAT WILL NEED TO BE MONITORED...BUT
KEEPING FORECAST GENERALLY DRY FOR NOW WEDNESDAY NIGHT THROUGH
THURSDAY NIGHT.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
HIPRES OVER NEW ENG WILL ALLOW AN ELY FLOW OF MOISTURE INTO THE
AREA. THIS WILL RESULT IN SOME MVFR CLD CIGS THIS MRNG...SLOWLY
RETURNING TO VFR IN THE LATE MRNG AS HTG ERODES THE CLDS.
OTRW...LTL IN THE WAY OF WX FOR THE NEST 24 HRS.
.OUTLOOK...
MONDAY NIGHT-TUESDAY NIGHT...CHC -SHRA AND ASSOCIATED
RESTRICTIONS. BEST CHANCE WITH FRONTAL PASSAGE TUE-TUE NGT.
WEDNESDAY-FRIDAY...MAINLY VFR EXCEPT FOR LOCAL RESTRICTIONS DUE
TO VALLEY FOG /MAINLY KELM/.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN
SHORT TERM...HEDEN
LONG TERM...MDP
AVIATION...DGM/DJP
AREA FORECAST DISCUSSION
NWS RALEIGH NC
149 PM EDT MON SEP 28 2015
.SYNOPSIS...DEEP ATLANTIC MOISTURE WILL CONTINUE TO PUMP INTO THE
REGION TODAY... BETWEEN CANADIAN HIGH PRESSURE TO OUR NORTHEAST AND
LOW PRESSURE JUST OFF THE SOUTHEAST COAST. THESE FEATURES WILL
WEAKEN TONIGHT INTO TUESDAY... RESULTING IN A BRIEF IMPROVEMENT IN
WEATHER CONDITIONS... HOWEVER A SURGE OF GULF MOISTURE AHEAD OF AN
APPROACHING COLD FRONT WILL BRING A RETURN TO WET AND UNSETTLED
WEATHER LATE TUESDAY THROUGH THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM MONDAY...
NO MAJOR CHANGES TO THE FORECAST THIS MORNING. VERY MOIST AIR MASS
REMAINS IN PLACE OVER THE REGION...WITH PWAT VALUES NEAR 2 INCHES
PER THE BLENDED TPW IMAGERY. A WEAK WAVE IS PROGGED TO TRACK
NORTHEASTWARD OVER EASTERN NC THIS AFTERNOON AND GIVEN SOME WEAK
DESTABILIZATION (ALREADY SEEING THIS ACROSS EASTERN NC PER THE SPC
MESOSCALE ANALYSIS)...PRECIP CHANCES WILL INCREASE THROUGH THE LATE
MORNING/EARLY AFTERNOON HOURS FROM EAST TO WEST (FOLLOWED THE HRRR
CLOSELY FOR THE TIMING). THIS AREA OF RAIN/SHOWERS SHOULD GRADUALLY
TRANSLATE ACROSS THE FORECAST AREA...WITH THE COASTAL PLAIN SEEING
THE BEST CHANCE OF RAIN IN THE NEXT FEW HOURS AND FURTHER WEST BY
MID/LATE AFTERNOON. PRECIP SHOULD DIMINISH THROUGH THE EVENING
HOURS...BUT LIGHT RAIN/DRIZZLE WILL BE POSSIBLE OVERNIGHT (AS HAS
BEEN THE CASE THE LAST SEVERAL DAYS).
PREVIOUS DISCUSSION AS OF 3 AM...COLUMN REMAINS VERY MOIST THIS
MORNING... ALTHOUGH THE EXTENT OF MOISTURE THROUGH THE COLUMN IS NOT
QUITE WHAT IT`S BEEN THE LAST COUPLE OF DAYS. WE`RE IN GRADUAL
TRANSITION AWAY FROM THE DYING WEDGE REGIME TO AN ATYPICALLY HUMID
(ESP FOR LATE SEPTEMBER) AIR MASS. THE PARENT HIGH WHICH BROUGHT THE
DAMMING OVER THE WEEKEND IS NOW CENTERED WELL OUT OVER THE NW
ATLANTIC YET STILL NOSING WEST AND SW INTO THE WRN CAROLINAS. THE
STABLE POOL OVER THE WRN PIEDMONT HAS WEAKENED... AND THE AIR MASS
HAS BECOME MORE HOMOGENEOUS ACROSS THE CWA... DEMONSTRATED BY
TEMP/DEWPOINT RANGES OF JUST AROUND 4 DEGREES ACROSS CENTRAL NC...
AND UNIFORM OBSERVED LIFTED INDICES AND CINH. MUCH OF THIS PAST
EVENING`S LIGHT PRECIP DRIVEN BY ISENTROPIC UPGLIDE HAS SHIFTED WELL
NW OUT OF THE AREA... LEAVING JUST WIDESPREAD STRATUS AND PERHAPS A
FEW ISOLATED DRIZZLE PATCHES. THIS RELATIVE LULL IN PRECIP WILL
CONTINUE THROUGH THE MID MORNING HOURS... HOWEVER AREAS OF SHOWERS
NOW JUST OFF THE NC COAST ARE ON TRACK TO TRANSLATE WEST OR WNW INTO
THE COASTAL PLAIN AND THEN INTO THE PIEDMONT FROM MID/LATE MORNING
THROUGH THE AFTERNOON... WITH COVERAGE FILLING IN AS HEATING ALLOWS
FOR A FEW HOLES IN THE CLOUDS AND SUBSEQUENT (WEAK)
DESTABILIZATION... WITH LIFT POTENTIALLY AUGMENTED BY A WEAK WAVE
TRACKING NE OVER ERN NC THIS AFTERNOON. EXPECT LOW POPS THIS
MORNING... TRENDING UP TO LIKELY EAST AND CHANCE WEST... WITH HIGHER
POPS THEN PUSHING WNW INTO THE WRN PIEDMONT AS WE GET INTO THE
EVENING HOURS... A PATTERN SUGGESTED BY RECENT RUNS OF BOTH LARGE
SCALE AND CONVECTION ALLOWING MODELS INCLUDING THE SREF/GFS/3 KM
NAMRR AND THE LATEST HRRR RUNS. FORECAST SOUNDINGS SHOW A DEEP WARM
LAYER THIS AFTERNOON WITH AN LCL-TO-FREEZING-LEVEL DEPTH OVER 4
KM... ALONG WITH PW VALUES OF 2.0-2.3 INCHES... SO ANY SHOWERS
FORMING TODAY WILL BE CAPABLE OF DROPPING BRIEF HEAVY RAIN. FORECAST
MUCAPE FOR TODAY IS UNIMPRESSIVE (UNDER 1000 J/KG... MOST OF WHICH
IS BELOW THE -10C LEVEL) WITH GENERALLY SUB-20-KT DEEP LAYER BULK
SHEAR... SO WILL NOT MENTION THUNDER AT THIS TIME... ALTHOUGH A
STRIKE OR TWO IS CERTAINLY POSSIBLE IN THE COASTAL PLAIN. EXPECT THE
AREA OF BETTER SHOWER COVERAGE TO CONTINUE SHIFTING WNW TOWARD THE
FOOTHILLS DURING THE EVENING... SO WILL TREND POPS DOWN FROM EAST TO
WEST TONIGHT... RESULTING IN 30-40% CHANCES NORTHWEST TRANSITIONING
DOWN TO JUST ISOLATED SHOWERS EAST OF HIGHWAY 1 OVERNIGHT. STRATUS
REDEVELOPMENT APPEARS LIKELY LATE TONIGHT GIVEN THE LOW LEVEL
MOISTURE AND TRAJECTORIES ALONG WITH PERSISTENCE... ALTHOUGH A LIGHT
BREEZE FROM THE NE -- AS MODELS SUGGEST -- MAY INHIBIT FOG
DEVELOPMENT. WILL LEAVE IN A MENTION OF PATCHY FOG FOR NOW. EXPECT
HIGHS FROM THE MID 70S NW (WHERE THE AIR IS STILL A BIT MORE STABLE
AND MORE RESISTANT TO MIXING AND THUS SHOULD SEE LESS SUNSHINE) TO
AROUND 80-82 EAST OF HIGHWAY 1... WITH MOSTLY CLOUDY SKIES. MILD
LOWS TONIGHT OF 67-71... AROUND 10 DEG ABOVE NORMAL. -GIH
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
AS OF 330 AM MONDAY...
CONTINUED MOIST WITH A GOOD CHANCE OF SHOWERS... AND PERHAPS A STORM
OR TWO. THE MID LEVEL TROUGH FROM THE LOWER GREAT LAKES THROUGH THE
LOWER MISS VALLEY TO LA WILL CONTINUE TO TILT SLOWLY... RESULTING IN
A GRADUAL INCREASE IN MID LEVEL VORTICITY MOVING FROM THE NW GULF
INTO THE CAROLINAS ON WEAK SOUTHWESTERLY MID LEVEL FLOW. THE LOW
LEVEL ATLANTIC INFLOW SHOULD BE ON THE DECREASE WITH A REDUCED
FETCH... A FUNCTION OF WHAT IS NOW TD #11 AS IT PUSHES SLOWLY NW/NNW
ON ITS ANTICIPATED TRACK TOWARD THE OFFSHORE WATERS OF NC. PW IS
PROJECTED TO REMAIN VERY HIGH AT 2.0-2.3 INCHES... WELL ABOVE
SEASONAL NORMALS... AND MODELS SHOW SLIGHTLY BETTER POTENTIAL FOR
INSTABILITY TUE AFTERNOON WITHIN PERSISTENT HIGH THETA-E ADVECTION
IN THE LOW LEVELS. DESPITE THE WEAK WIND FIELD AND MARGINAL DPVA...
WE SHOULD SEE DECENT UPPER DIVERGENCE OVER THE AREA IN THE LEFT EXIT
REGION OF THE BROAD JET FROM THE GULF INTO THE TN VALLEY. WILL TREND
POPS UP TO LIKELY OVER MUCH OF THE CWA BY AFTERNOON... WANING
GRADUALLY IN THE EVENING/NIGHTTIME BUT STAYING AT 30-50%... WITH
BETTER SHOWER CHANCES SHIFTING WNW INTO THE NW PIEDMONT AND
FOOTHILLS WITH TIME. SLIGHTLY BETTER CAPE AND SHEAR ARE EXPECTED...
STILL MARGINAL THOUGH... SO HAVE INCLUDED JUST A MENTION OF ISOLATED
THUNDER IN THE AFTERNOON. HIGHS 75-83 AND LOWS 66-71... BOTH ABOVE
NORMAL... WITH MOSTLY CLOUDY SKIES HOLDING FIRM. -GIH
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 327 AM MONDAY...
UNCERTAINTY IN THE FORECAST IS ABOUT AS HIGH AS CAN BE ADVERTISED
FROM MID WEEK INTO THE WEEKEND. THE OPERATIONAL MODELS CONTINUE TO
SHOW PLENTY OF SPREAD AND EVEN THE ENSEMBLE MEANS ARE CONFLICTING ON
THE PLACEMENT OF THE IMPORTANT WEATHER PRODUCING SYSTEMS. THE MAIN
WEATHER HAZARDS SHOULD BE LIMITED TO A LOW END HEAVY RAIN THREAT...
BUT SIGNIFICANT RAINFALL MAY BE MORE OF A HELP TO CURRENT DROUGHT
STATUS THAN IT WOULD BE A THREAT FOR FLOODING. THE QPF MID TO LATE
WEEK IS THE MAIN QUESTION AS ABOUT 30 PERCENT OF THE MODELS INDICATE
THE HEAVIEST RAIN INLAND WITH OVERRUNNING RAINS AGAIN THU NIGHT INTO
SATURDAY... WHICH 70 PERCENT OF THE MODELS SUPPORT THE HEAVY SWATH
OF QPF ALONG OR JUST OFF THE MID-ATLANTIC COAST.
ONE THING SEEMS TO BE MORE CERTAIN SHOULD BE THE COOLER TEMPERATURES
AGAIN AS ANOTHER STRONG SURFACE HIGH IS EXPECTED TO BUILD SOUTH INTO
NC/SC THURSDAY INTO THE WEEKEND. THIS OCCURS AS A TROUGH ALOFT AND
LINGERING LOW LEVEL BOUNDARY CONTINUE TO BE FORECAST BY MOST MODELS
TO BRING A CONTINUATION OF THE UNSETTLED PATTERN THAT BEGAN LATE
LAST WEEK. A RETURN TO A PROLONGED NE FLOW... CONSIDERABLE
CLOUDINESS... AND POSSIBLY SIGNIFICANT RAIN IS EXPECTED THU-SAT.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 145 PM MONDAY...
ADVERSE AVIATION CONDITIONS ARE EXPECTED TO PERSIST THROUGH THE
CURRENT TAF PERIOD AS A VERY MOIST AIR MASS REMAINS ENTRENCHED OVER
THE REGION. THERE COULD BE A BRIEF IMPROVEMENT TO VFR THIS
AFTERNOON...MAINLY ACROSS THE EAST (KRDU/KFAY/KRWI)...WHILE THE
TRIAD (KGSO/KINT) MAY IMPROVE SOME FROM THEIR CURRENT IFR STATE...
BUT ONLY TO MVFR. SCATTERED SHOWERS ARE POSSIBLE THIS AFTERNOON AND
EVENING AND THESE COULD PRODUCE A BRIEF PERIOD OF SUB-VFR VSBYS.
PRECIP WILL DECREASE DURING THE OVERNIGHT HOURS...BUT LIGHT RAIN
AND/OR DRIZZLE WILL BE POSSIBLE ALL NIGHT. ALL SITES ARE EXPECTED TO
DETERIORATE ONCE AGAIN LATER THIS EVENING AND THEN PERSIST ALL
NIGHT...WITH POTENTIAL IFR/LIFR CIGS/VSBYS FORMING OVERNIGHT.
TUESDAY WILL BE SIMILAR TO TODAY...AS CONDITIONS WILL SLOWLY IMPROVE
THROUGH THE EARLY AFTERNOON HOURS...WITH KRDU/KRWI/KFAY LIFTING TO
MVFR THEN PERHAPS LOW-END VFR AND KINT/KGSO LIKELY STAYING MVFR
THROUGH TUESDAY AFTERNOON. -KRD
OUTLOOK...IFR/LIFR CONDITIONS IN FOG ARE EXPECTED TO RETURN ONE
AGAIN LATE TUE EVENING THROUGH DAYBREAK WED. VFR CONDITIONS SHOULD
RETURN FOR MIDDAY WED BUT SHOWERS/STORMS AHEAD OF A COLD FRONT MAY
BRING SUB-VFR CONDITIONS WED/WED NIGHT. THIS FRONT WILL MOVE THROUGH
WED NIGHT AND STALL TO OUR SE INTO THE EARLY WEEKEND...POTENTIALLY
BRINGING A RETURN TO PREDOMINANTLY POOR AVIATION CONDITIONS WITHIN
AREAS OF RAIN/DRIZZLE. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...KRD/HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...BADGETT
AVIATION...KRD/HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1037 AM EDT MON SEP 28 2015
.SYNOPSIS...DEEP ATLANTIC MOISTURE WILL CONTINUE TO PUMP INTO THE
REGION TODAY... BETWEEN CANADIAN HIGH PRESSURE TO OUR NORTHEAST AND
LOW PRESSURE JUST OFF THE SOUTHEAST COAST. THESE FEATURES WILL
WEAKEN TONIGHT INTO TUESDAY... RESULTING IN A BRIEF IMPROVEMENT IN
WEATHER CONDITIONS... HOWEVER A SURGE OF GULF MOISTURE AHEAD OF AN
APPROACHING COLD FRONT WILL BRING A RETURN TO WET AND UNSETTLED
WEATHER LATE TUESDAY THROUGH THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM MONDAY...
NO MAJOR CHANGES TO THE FORECAST THIS MORNING. VERY MOIST AIR MASS
REMAINS IN PLACE OVER THE REGION...WITH PWAT VALUES NEAR 2 INCHES
PER THE BLENDED TPW IMAGERY. A WEAK WAVE IS PROGGED TO TRACK
NORTHEASTWARD OVER EASTERN NC THIS AFTERNOON AND GIVEN SOME WEAK
DESTABILIZATION (ALREADY SEEING THIS ACROSS EASTERN NC PER THE SPC
MESOSCALE ANALYSIS)...PRECIP CHANCES WILL INCREASE THROUGH THE LATE
MORNING/EARLY AFTERNOON HOURS FROM EAST TO WEST (FOLLOWED THE HRRR
CLOSELY FOR THE TIMING). THIS AREA OF RAIN/SHOWERS SHOULD GRADUALLY
TRANSLATE ACROSS THE FORECAST AREA...WITH THE COASTAL PLAIN SEEING
THE BEST CHANCE OF RAIN IN THE NEXT FEW HOURS AND FURTHER WEST BY
MID/LATE AFTERNOON. PRECIP SHOULD DIMINISH THROUGH THE EVENING
HOURS...BUT LIGHT RAIN/DRIZZLE WILL BE POSSIBLE OVERNIGHT (AS HAS
BEEN THE CASE THE LAST SEVERAL DAYS).
PREVIOUS DISCUSSION AS OF 3 AM...COLUMN REMAINS VERY MOIST THIS
MORNING... ALTHOUGH THE EXTENT OF MOISTURE THROUGH THE COLUMN IS NOT
QUITE WHAT IT`S BEEN THE LAST COUPLE OF DAYS. WE`RE IN GRADUAL
TRANSITION AWAY FROM THE DYING WEDGE REGIME TO AN ATYPICALLY HUMID
(ESP FOR LATE SEPTEMBER) AIR MASS. THE PARENT HIGH WHICH BROUGHT THE
DAMMING OVER THE WEEKEND IS NOW CENTERED WELL OUT OVER THE NW
ATLANTIC YET STILL NOSING WEST AND SW INTO THE WRN CAROLINAS. THE
STABLE POOL OVER THE WRN PIEDMONT HAS WEAKENED... AND THE AIR MASS
HAS BECOME MORE HOMOGENEOUS ACROSS THE CWA... DEMONSTRATED BY
TEMP/DEWPOINT RANGES OF JUST AROUND 4 DEGREES ACROSS CENTRAL NC...
AND UNIFORM OBSERVED LIFTED INDICES AND CINH. MUCH OF THIS PAST
EVENING`S LIGHT PRECIP DRIVEN BY ISENTROPIC UPGLIDE HAS SHIFTED WELL
NW OUT OF THE AREA... LEAVING JUST WIDESPREAD STRATUS AND PERHAPS A
FEW ISOLATED DRIZZLE PATCHES. THIS RELATIVE LULL IN PRECIP WILL
CONTINUE THROUGH THE MID MORNING HOURS... HOWEVER AREAS OF SHOWERS
NOW JUST OFF THE NC COAST ARE ON TRACK TO TRANSLATE WEST OR WNW INTO
THE COASTAL PLAIN AND THEN INTO THE PIEDMONT FROM MID/LATE MORNING
THROUGH THE AFTERNOON... WITH COVERAGE FILLING IN AS HEATING ALLOWS
FOR A FEW HOLES IN THE CLOUDS AND SUBSEQUENT (WEAK)
DESTABILIZATION... WITH LIFT POTENTIALLY AUGMENTED BY A WEAK WAVE
TRACKING NE OVER ERN NC THIS AFTERNOON. EXPECT LOW POPS THIS
MORNING... TRENDING UP TO LIKELY EAST AND CHANCE WEST... WITH HIGHER
POPS THEN PUSHING WNW INTO THE WRN PIEDMONT AS WE GET INTO THE
EVENING HOURS... A PATTERN SUGGESTED BY RECENT RUNS OF BOTH LARGE
SCALE AND CONVECTION ALLOWING MODELS INCLUDING THE SREF/GFS/3 KM
NAMRR AND THE LATEST HRRR RUNS. FORECAST SOUNDINGS SHOW A DEEP WARM
LAYER THIS AFTERNOON WITH AN LCL-TO-FREEZING-LEVEL DEPTH OVER 4
KM... ALONG WITH PW VALUES OF 2.0-2.3 INCHES... SO ANY SHOWERS
FORMING TODAY WILL BE CAPABLE OF DROPPING BRIEF HEAVY RAIN. FORECAST
MUCAPE FOR TODAY IS UNIMPRESSIVE (UNDER 1000 J/KG... MOST OF WHICH
IS BELOW THE -10C LEVEL) WITH GENERALLY SUB-20-KT DEEP LAYER BULK
SHEAR... SO WILL NOT MENTION THUNDER AT THIS TIME... ALTHOUGH A
STRIKE OR TWO IS CERTAINLY POSSIBLE IN THE COASTAL PLAIN. EXPECT THE
AREA OF BETTER SHOWER COVERAGE TO CONTINUE SHIFTING WNW TOWARD THE
FOOTHILLS DURING THE EVENING... SO WILL TREND POPS DOWN FROM EAST TO
WEST TONIGHT... RESULTING IN 30-40% CHANCES NORTHWEST TRANSITIONING
DOWN TO JUST ISOLATED SHOWERS EAST OF HIGHWAY 1 OVERNIGHT. STRATUS
REDEVELOPMENT APPEARS LIKELY LATE TONIGHT GIVEN THE LOW LEVEL
MOISTURE AND TRAJECTORIES ALONG WITH PERSISTENCE... ALTHOUGH A LIGHT
BREEZE FROM THE NE -- AS MODELS SUGGEST -- MAY INHIBIT FOG
DEVELOPMENT. WILL LEAVE IN A MENTION OF PATCHY FOG FOR NOW. EXPECT
HIGHS FROM THE MID 70S NW (WHERE THE AIR IS STILL A BIT MORE STABLE
AND MORE RESISTANT TO MIXING AND THUS SHOULD SEE LESS SUNSHINE) TO
AROUND 80-82 EAST OF HIGHWAY 1... WITH MOSTLY CLOUDY SKIES. MILD
LOWS TONIGHT OF 67-71... AROUND 10 DEG ABOVE NORMAL. -GIH
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
AS OF 330 AM MONDAY...
CONTINUED MOIST WITH A GOOD CHANCE OF SHOWERS... AND PERHAPS A STORM
OR TWO. THE MID LEVEL TROUGH FROM THE LOWER GREAT LAKES THROUGH THE
LOWER MISS VALLEY TO LA WILL CONTINUE TO TILT SLOWLY... RESULTING IN
A GRADUAL INCREASE IN MID LEVEL VORTICITY MOVING FROM THE NW GULF
INTO THE CAROLINAS ON WEAK SOUTHWESTERLY MID LEVEL FLOW. THE LOW
LEVEL ATLANTIC INFLOW SHOULD BE ON THE DECREASE WITH A REDUCED
FETCH... A FUNCTION OF WHAT IS NOW TD #11 AS IT PUSHES SLOWLY NW/NNW
ON ITS ANTICIPATED TRACK TOWARD THE OFFSHORE WATERS OF NC. PW IS
PROJECTED TO REMAIN VERY HIGH AT 2.0-2.3 INCHES... WELL ABOVE
SEASONAL NORMALS... AND MODELS SHOW SLIGHTLY BETTER POTENTIAL FOR
INSTABILITY TUE AFTERNOON WITHIN PERSISTENT HIGH THETA-E ADVECTION
IN THE LOW LEVELS. DESPITE THE WEAK WIND FIELD AND MARGINAL DPVA...
WE SHOULD SEE DECENT UPPER DIVERGENCE OVER THE AREA IN THE LEFT EXIT
REGION OF THE BROAD JET FROM THE GULF INTO THE TN VALLEY. WILL TREND
POPS UP TO LIKELY OVER MUCH OF THE CWA BY AFTERNOON... WANING
GRADUALLY IN THE EVENING/NIGHTTIME BUT STAYING AT 30-50%... WITH
BETTER SHOWER CHANCES SHIFTING WNW INTO THE NW PIEDMONT AND
FOOTHILLS WITH TIME. SLIGHTLY BETTER CAPE AND SHEAR ARE EXPECTED...
STILL MARGINAL THOUGH... SO HAVE INCLUDED JUST A MENTION OF ISOLATED
THUNDER IN THE AFTERNOON. HIGHS 75-83 AND LOWS 66-71... BOTH ABOVE
NORMAL... WITH MOSTLY CLOUDY SKIES HOLDING FIRM. -GIH
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 327 AM MONDAY...
UNCERTAINTY IN THE FORECAST IS ABOUT AS HIGH AS CAN BE ADVERTISED
FROM MID WEEK INTO THE WEEKEND. THE OPERATIONAL MODELS CONTINUE TO
SHOW PLENTY OF SPREAD AND EVEN THE ENSEMBLE MEANS ARE CONFLICTING ON
THE PLACEMENT OF THE IMPORTANT WEATHER PRODUCING SYSTEMS. THE MAIN
WEATHER HAZARDS SHOULD BE LIMITED TO A LOW END HEAVY RAIN THREAT...
BUT SIGNIFICANT RAINFALL MAY BE MORE OF A HELP TO CURRENT DROUGHT
STATUS THAN IT WOULD BE A THREAT FOR FLOODING. THE QPF MID TO LATE
WEEK IS THE MAIN QUESTION AS ABOUT 30 PERCENT OF THE MODELS INDICATE
THE HEAVIEST RAIN INLAND WITH OVERRUNNING RAINS AGAIN THU NIGHT INTO
SATURDAY... WHICH 70 PERCENT OF THE MODELS SUPPORT THE HEAVY SWATH
OF QPF ALONG OR JUST OFF THE MID-ATLANTIC COAST.
ONE THING SEEMS TO BE MORE CERTAIN SHOULD BE THE COOLER TEMPERATURES
AGAIN AS ANOTHER STRONG SURFACE HIGH IS EXPECTED TO BUILD SOUTH INTO
NC/SC THURSDAY INTO THE WEEKEND. THIS OCCURS AS A TROUGH ALOFT AND
LINGERING LOW LEVEL BOUNDARY CONTINUE TO BE FORECAST BY MOST MODELS
TO BRING A CONTINUATION OF THE UNSETTLED PATTERN THAT BEGAN LATE
LAST WEEK. A RETURN TO A PROLONGED NE FLOW... CONSIDERABLE
CLOUDINESS... AND POSSIBLY SIGNIFICANT RAIN IS EXPECTED THU-SAT.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
AS OF 640 AM MONDAY...
MOIST AND DEEP LOW LEVEL FLOW FROM THE EAST WILL CONTINUE TO BRING
MOSTLY ADVERSE AVIATION CONDITIONS TODAY... ESPECIALLY AT INT/GSO...
WHERE IFR/LIFR CIGS AND MVFR/IFR VSBYS ARE LIKELY TO HOLD THROUGH
14Z... ALONG WITH PATCHY DRIZZLE. FARTHER EAST AT RDU/RWI/FAY...
MVFR CIGS SHOULD HOLD THROUGH 14Z... ALTHOUGH A SHORT PERIOD OF IFR
IS POSSIBLE. SOON AFTER 14Z... CIGS AT ALL LOCATIONS SHOULD SLOWLY
BEGIN TO LIFT THROUGH THE MVFR CATEGORY... LASTING UNTIL AROUND 18Z
OR 19Z WHEN SOME BREAKS IN THE CLOUDS ARE EXPECTED... ALTHOUGH ANY
SCT/BKN CLOUDS ARE STILL LIKELY TO BE BASED AT 2500-3000 FT AGL. A
TREND BACK TO MVFR TO IFR CIGS IS EXPECTED BY MID EVENING (AFTER 00Z
TUE)... LASTING THROUGH TONIGHT... WITH POTENTIAL IFR/LIFR FOG
FORMING OVERNIGHT. A FEW SHOWERS ARE POSSIBLE ESPECIALLY THIS
AFTERNOON AND THESE COULD PRODUCE A PERIOD OF SUB-VFR VSBYS.
LOOKING BEYOND 12Z TUE: IFR CONDITIONS ARE EXPECTED TO RULE THROUGH
DAYBREAK TUE... ALTHOUGH RWI MAY STAY MVFR FOR MUCH OF THE NIGHT
WITH PATCHY FOG. INT/GSO SHOULD STAY MVFR THROUGH TUE BUT
RDU/RWI/FAY SHOULD LIFT TO MVFR THEN PERHAPS LOW-END VFR TUE
AFTERNOON. IFR/LIFR CONDITIONS IN FOG ARE EXPECTED TO RETURN LATE
TUE EVENING THROUGH DAYBREAK WED. VFR CONDITIONS THROUGH MIDDAY WED
BUT SHOWERS/STORMS AHEAD OF A COLD FRONT MAY BRING SUB-VFR
CONDITIONS WED/WED NIGHT. THIS FRONT WILL MOVE THROUGH WED NIGHT AND
STALL TO OUR SE INTO FRI... POTENTIALLY BRINGING A RETURN TO
PREDOMINANTLY POOR AVIATION CONDITIONS WITHIN AREAS OF RAIN/DRIZZLE.
-GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...KRD/HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...BADGETT
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
640 AM EDT MON SEP 28 2015
.SYNOPSIS...DEEP ATLANTIC MOISTURE WILL CONTINUE TO PUMP INTO THE
REGION TODAY... BETWEEN CANADIAN HIGH PRESSURE TO OUR NORTHEAST AND
LOW PRESSURE JUST OFF THE SOUTHEAST COAST. THESE FEATURES WILL
WEAKEN TONIGHT INTO TUESDAY... RESULTING IN A BRIEF IMPROVEMENT IN
WEATHER CONDITIONS... HOWEVER A SURGE OF GULF MOISTURE AHEAD OF AN
APPROACHING COLD FRONT WILL BRING A RETURN TO WET AND UNSETTLED
WEATHER LATE TUESDAY THROUGH THURSDAY.
&&
.NEAR TERM /TODAY THROUGH TONIGHT/...
AS OF 320 AM MONDAY...
COLUMN REMAINS VERY MOIST THIS MORNING... ALTHOUGH THE EXTENT OF
MOISTURE THROUGH THE COLUMN IS NOT QUITE WHAT IT`S BEEN THE LAST
COUPLE OF DAYS. WE`RE IN GRADUAL TRANSITION AWAY FROM THE DYING
WEDGE REGIME TO AN ATYPICALLY HUMID (ESP FOR LATE SEPTEMBER) AIR
MASS. THE PARENT HIGH WHICH BROUGHT THE DAMMING OVER THE WEEKEND IS
NOW CENTERED WELL OUT OVER THE NW ATLANTIC YET STILL NOSING WEST AND
SW INTO THE WRN CAROLINAS. THE STABLE POOL OVER THE WRN PIEDMONT HAS
WEAKENED... AND THE AIR MASS HAS BECOME MORE HOMOGENEOUS ACROSS THE
CWA... DEMONSTRATED BY TEMP/DEWPOINT RANGES OF JUST AROUND 4 DEGREES
ACROSS CENTRAL NC... AND UNIFORM OBSERVED LIFTED INDICES AND CINH.
MUCH OF THIS PAST EVENING`S LIGHT PRECIP DRIVEN BY ISENTROPIC
UPGLIDE HAS SHIFTED WELL NW OUT OF THE AREA... LEAVING JUST
WIDESPREAD STRATUS AND PERHAPS A FEW ISOLATED DRIZZLE PATCHES. THIS
RELATIVE LULL IN PRECIP WILL CONTINUE THROUGH THE MID MORNING
HOURS... HOWEVER AREAS OF SHOWERS NOW JUST OFF THE NC COAST ARE ON
TRACK TO TRANSLATE WEST OR WNW INTO THE COASTAL PLAIN AND THEN INTO
THE PIEDMONT FROM MID/LATE MORNING THROUGH THE AFTERNOON... WITH
COVERAGE FILLING IN AS HEATING ALLOWS FOR A FEW HOLES IN THE CLOUDS
AND SUBSEQUENT (WEAK) DESTABILIZATION... WITH LIFT POTENTIALLY
AUGMENTED BY A WEAK WAVE TRACKING NE OVER ERN NC THIS AFTERNOON.
EXPECT LOW POPS THIS MORNING... TRENDING UP TO LIKELY EAST AND
CHANCE WEST... WITH HIGHER POPS THEN PUSHING WNW INTO THE WRN
PIEDMONT AS WE GET INTO THE EVENING HOURS... A PATTERN SUGGESTED BY
RECENT RUNS OF BOTH LARGE SCALE AND CONVECTION ALLOWING MODELS
INCLUDING THE SREF/GFS/3 KM NAMRR AND THE LATEST HRRR RUNS. FORECAST
SOUNDINGS SHOW A DEEP WARM LAYER THIS AFTERNOON WITH AN LCL-TO-
FREEZING-LEVEL DEPTH OVER 4 KM... ALONG WITH PW VALUES OF 2.0-2.3
INCHES... SO ANY SHOWERS FORMING TODAY WILL BE CAPABLE OF DROPPING
BRIEF HEAVY RAIN. FORECAST MUCAPE FOR TODAY IS UNIMPRESSIVE (UNDER
1000 J/KG... MOST OF WHICH IS BELOW THE -10C LEVEL) WITH GENERALLY
SUB-20-KT DEEP LAYER BULK SHEAR... SO WILL NOT MENTION THUNDER AT
THIS TIME... ALTHOUGH A STRIKE OR TWO IS CERTAINLY POSSIBLE IN THE
COASTAL PLAIN. EXPECT THE AREA OF BETTER SHOWER COVERAGE TO CONTINUE
SHIFTING WNW TOWARD THE FOOTHILLS DURING THE EVENING... SO WILL
TREND POPS DOWN FROM EAST TO WEST TONIGHT... RESULTING IN 30-40%
CHANCES NORTHWEST TRANSITIONING DOWN TO JUST ISOLATED SHOWERS EAST
OF HIGHWAY 1 OVERNIGHT. STRATUS REDEVELOPMENT APPEARS LIKELY LATE
TONIGHT GIVEN THE LOW LEVEL MOISTURE AND TRAJECTORIES ALONG WITH
PERSISTENCE... ALTHOUGH A LIGHT BREEZE FROM THE NE -- AS MODELS
SUGGEST -- MAY INHIBIT FOG DEVELOPMENT. WILL LEAVE IN A MENTION OF
PATCHY FOG FOR NOW. EXPECT HIGHS FROM THE MID 70S NW (WHERE THE AIR
IS STILL A BIT MORE STABLE AND MORE RESISTANT TO MIXING AND THUS
SHOULD SEE LESS SUNSHINE) TO AROUND 80-82 EAST OF HIGHWAY 1... WITH
MOSTLY CLOUDY SKIES. MILD LOWS TONIGHT OF 67-71... AROUND 10 DEG
ABOVE NORMAL. -GIH
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
AS OF 330 AM MONDAY...
CONTINUED MOIST WITH A GOOD CHANCE OF SHOWERS... AND PERHAPS A STORM
OR TWO. THE MID LEVEL TROUGH FROM THE LOWER GREAT LAKES THROUGH THE
LOWER MISS VALLEY TO LA WILL CONTINUE TO TILT SLOWLY... RESULTING IN
A GRADUAL INCREASE IN MID LEVEL VORTICITY MOVING FROM THE NW GULF
INTO THE CAROLINAS ON WEAK SOUTHWESTERLY MID LEVEL FLOW. THE LOW
LEVEL ATLANTIC INFLOW SHOULD BE ON THE DECREASE WITH A REDUCED
FETCH... A FUNCTION OF WHAT IS NOW TD #11 AS IT PUSHES SLOWLY NW/NNW
ON ITS ANTICIPATED TRACK TOWARD THE OFFSHORE WATERS OF NC. PW IS
PROJECTED TO REMAIN VERY HIGH AT 2.0-2.3 INCHES... WELL ABOVE
SEASONAL NORMALS... AND MODELS SHOW SLIGHTLY BETTER POTENTIAL FOR
INSTABILITY TUE AFTERNOON WITHIN PERSISTENT HIGH THETA-E ADVECTION
IN THE LOW LEVELS. DESPITE THE WEAK WIND FIELD AND MARGINAL DPVA...
WE SHOULD SEE DECENT UPPER DIVERGENCE OVER THE AREA IN THE LEFT EXIT
REGION OF THE BROAD JET FROM THE GULF INTO THE TN VALLEY. WILL TREND
POPS UP TO LIKELY OVER MUCH OF THE CWA BY AFTERNOON... WANING
GRADUALLY IN THE EVENING/NIGHTTIME BUT STAYING AT 30-50%... WITH
BETTER SHOWER CHANCES SHIFTING WNW INTO THE NW PIEDMONT AND
FOOTHILLS WITH TIME. SLIGHTLY BETTER CAPE AND SHEAR ARE EXPECTED...
STILL MARGINAL THOUGH... SO HAVE INCLUDED JUST A MENTION OF ISOLATED
THUNDER IN THE AFTERNOON. HIGHS 75-83 AND LOWS 66-71... BOTH ABOVE
NORMAL... WITH MOSTLY CLOUDY SKIES HOLDING FIRM. -GIH
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 327 AM MONDAY...
UNCERTAINTY IN THE FORECAST IS ABOUT AS HIGH AS CAN BE ADVERTISED
FROM MID WEEK INTO THE WEEKEND. THE OPERATIONAL MODELS CONTINUE TO
SHOW PLENTY OF SPREAD AND EVEN THE ENSEMBLE MEANS ARE CONFLICTING ON
THE PLACEMENT OF THE IMPORTANT WEATHER PRODUCING SYSTEMS. THE MAIN
WEATHER HAZARDS SHOULD BE LIMITED TO A LOW END HEAVY RAIN THREAT...
BUT SIGNIFICANT RAINFALL MAY BE MORE OF A HELP TO CURRENT DROUGHT
STATUS THAN IT WOULD BE A THREAT FOR FLOODING. THE QPF MID TO LATE
WEEK IS THE MAIN QUESTION AS ABOUT 30 PERCENT OF THE MODELS INDICATE
THE HEAVIEST RAIN INLAND WITH OVERRUNNING RAINS AGAIN THU NIGHT INTO
SATURDAY... WHICH 70 PERCENT OF THE MODELS SUPPORT THE HEAVY SWATH
OF QPF ALONG OR JUST OFF THE MID-ATLANTIC COAST.
ONE THING SEEMS TO BE MORE CERTAIN SHOULD BE THE COOLER TEMPERATURES
AGAIN AS ANOTHER STRONG SURFACE HIGH IS EXPECTED TO BUILD SOUTH INTO
NC/SC THURSDAY INTO THE WEEKEND. THIS OCCURS AS A TROUGH ALOFT AND
LINGERING LOW LEVEL BOUNDARY CONTINUE TO BE FORECAST BY MOST MODELS
TO BRING A CONTINUATION OF THE UNSETTLED PATTERN THAT BEGAN LATE
LAST WEEK. A RETURN TO A PROLONGED NE FLOW... CONSIDERABLE
CLOUDINESS... AND POSSIBLY SIGNIFICANT RAIN IS EXPECTED THU-SAT.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
AS OF 640 AM MONDAY...
MOIST AND DEEP LOW LEVEL FLOW FROM THE EAST WILL CONTINUE TO BRING
MOSTLY ADVERSE AVIATION CONDITIONS TODAY... ESPECIALLY AT INT/GSO...
WHERE IFR/LIFR CIGS AND MVFR/IFR VSBYS ARE LIKELY TO HOLD THROUGH
14Z... ALONG WITH PATCHY DRIZZLE. FARTHER EAST AT RDU/RWI/FAY...
MVFR CIGS SHOULD HOLD THROUGH 14Z... ALTHOUGH A SHORT PERIOD OF IFR
IS POSSIBLE. SOON AFTER 14Z... CIGS AT ALL LOCATIONS SHOULD SLOWLY
BEGIN TO LIFT THROUGH THE MVFR CATEGORY... LASTING UNTIL AROUND 18Z
OR 19Z WHEN SOME BREAKS IN THE CLOUDS ARE EXPECTED... ALTHOUGH ANY
SCT/BKN CLOUDS ARE STILL LIKELY TO BE BASED AT 2500-3000 FT AGL. A
TREND BACK TO MVFR TO IFR CIGS IS EXPECTED BY MID EVENING (AFTER 00Z
TUE)... LASTING THROUGH TONIGHT... WITH POTENTIAL IFR/LIFR FOG
FORMING OVERNIGHT. A FEW SHOWERS ARE POSSIBLE ESPECIALLY THIS
AFTERNOON AND THESE COULD PRODUCE A PERIOD OF SUB-VFR VSBYS.
LOOKING BEYOND 12Z TUE: IFR CONDITIONS ARE EXPECTED TO RULE THROUGH
DAYBREAK TUE... ALTHOUGH RWI MAY STAY MVFR FOR MUCH OF THE NIGHT
WITH PATCHY FOG. INT/GSO SHOULD STAY MVFR THROUGH TUE BUT
RDU/RWI/FAY SHOULD LIFT TO MVFR THEN PERHAPS LOW-END VFR TUE
AFTERNOON. IFR/LIFR CONDITIONS IN FOG ARE EXPECTED TO RETURN LATE
TUE EVENING THROUGH DAYBREAK WED. VFR CONDITIONS THROUGH MIDDAY WED
BUT SHOWERS/STORMS AHEAD OF A COLD FRONT MAY BRING SUB-VFR
CONDITIONS WED/WED NIGHT. THIS FRONT WILL MOVE THROUGH WED NIGHT AND
STALL TO OUR SE INTO FRI... POTENTIALLY BRINGING A RETURN TO
PREDOMINANTLY POOR AVIATION CONDITIONS WITHIN AREAS OF RAIN/DRIZZLE.
-GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...BADGETT
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
340 AM EDT MON SEP 28 2015
.SYNOPSIS...DEEP ATLANTIC MOISTURE WILL CONTINUE TO PUMP INTO THE
REGION TODAY... BETWEEN CANADIAN HIGH PRESSURE TO OUR NORTHEAST AND
LOW PRESSURE JUST OFF THE SOUTHEAST COAST. THESE FEATURES WILL
WEAKEN TONIGHT INTO TUESDAY... RESULTING IN A BRIEF IMPROVEMENT IN
WEATHER CONDITIONS... HOWEVER A SURGE OF GULF MOISTURE AHEAD OF AN
APPROACHING COLD FRONT WILL BRING A RETURN TO WET AND UNSETTLED
WEATHER LATE TUESDAY THROUGH THURSDAY.
&&
.NEAR TERM /TODAY THROUGH TONIGHT/...
AS OF 320 AM MONDAY...
COLUMN REMAINS VERY MOIST THIS MORNING... ALTHOUGH THE EXTENT OF
MOISTURE THROUGH THE COLUMN IS NOT QUITE WHAT IT`S BEEN THE LAST
COUPLE OF DAYS. WE`RE IN GRADUAL TRANSITION AWAY FROM THE DYING
WEDGE REGIME TO AN ATYPICALLY HUMID (ESP FOR LATE SEPTEMBER) AIR
MASS. THE PARENT HIGH WHICH BROUGHT THE DAMMING OVER THE WEEKEND IS
NOW CENTERED WELL OUT OVER THE NW ATLANTIC YET STILL NOSING WEST AND
SW INTO THE WRN CAROLINAS. THE STABLE POOL OVER THE WRN PIEDMONT HAS
WEAKENED... AND THE AIR MASS HAS BECOME MORE HOMOGENEOUS ACROSS THE
CWA... DEMONSTRATED BY TEMP/DEWPOINT RANGES OF JUST AROUND 4 DEGREES
ACROSS CENTRAL NC... AND UNIFORM OBSERVED LIFTED INDICES AND CINH.
MUCH OF THIS PAST EVENING`S LIGHT PRECIP DRIVEN BY ISENTROPIC
UPGLIDE HAS SHIFTED WELL NW OUT OF THE AREA... LEAVING JUST
WIDESPREAD STRATUS AND PERHAPS A FEW ISOLATED DRIZZLE PATCHES. THIS
RELATIVE LULL IN PRECIP WILL CONTINUE THROUGH THE MID MORNING
HOURS... HOWEVER AREAS OF SHOWERS NOW JUST OFF THE NC COAST ARE ON
TRACK TO TRANSLATE WEST OR WNW INTO THE COASTAL PLAIN AND THEN INTO
THE PIEDMONT FROM MID/LATE MORNING THROUGH THE AFTERNOON... WITH
COVERAGE FILLING IN AS HEATING ALLOWS FOR A FEW HOLES IN THE CLOUDS
AND SUBSEQUENT (WEAK) DESTABILIZATION... WITH LIFT POTENTIALLY
AUGMENTED BY A WEAK WAVE TRACKING NE OVER ERN NC THIS AFTERNOON.
EXPECT LOW POPS THIS MORNING... TRENDING UP TO LIKELY EAST AND
CHANCE WEST... WITH HIGHER POPS THEN PUSHING WNW INTO THE WRN
PIEDMONT AS WE GET INTO THE EVENING HOURS... A PATTERN SUGGESTED BY
RECENT RUNS OF BOTH LARGE SCALE AND CONVECTION ALLOWING MODELS
INCLUDING THE SREF/GFS/3 KM NAMRR AND THE LATEST HRRR RUNS. FORECAST
SOUNDINGS SHOW A DEEP WARM LAYER THIS AFTERNOON WITH AN LCL-TO-
FREEZING-LEVEL DEPTH OVER 4 KM... ALONG WITH PW VALUES OF 2.0-2.3
INCHES... SO ANY SHOWERS FORMING TODAY WILL BE CAPABLE OF DROPPING
BRIEF HEAVY RAIN. FORECAST MUCAPE FOR TODAY IS UNIMPRESSIVE (UNDER
1000 J/KG... MOST OF WHICH IS BELOW THE -10C LEVEL) WITH GENERALLY
SUB-20-KT DEEP LAYER BULK SHEAR... SO WILL NOT MENTION THUNDER AT
THIS TIME... ALTHOUGH A STRIKE OR TWO IS CERTAINLY POSSIBLE IN THE
COASTAL PLAIN. EXPECT THE AREA OF BETTER SHOWER COVERAGE TO CONTINUE
SHIFTING WNW TOWARD THE FOOTHILLS DURING THE EVENING... SO WILL
TREND POPS DOWN FROM EAST TO WEST TONIGHT... RESULTING IN 30-40%
CHANCES NORTHWEST TRANSITIONING DOWN TO JUST ISOLATED SHOWERS EAST
OF HIGHWAY 1 OVERNIGHT. STRATUS REDEVELOPMENT APPEARS LIKELY LATE
TONIGHT GIVEN THE LOW LEVEL MOISTURE AND TRAJECTORIES ALONG WITH
PERSISTENCE... ALTHOUGH A LIGHT BREEZE FROM THE NE -- AS MODELS
SUGGEST -- MAY INHIBIT FOG DEVELOPMENT. WILL LEAVE IN A MENTION OF
PATCHY FOG FOR NOW. EXPECT HIGHS FROM THE MID 70S NW (WHERE THE AIR
IS STILL A BIT MORE STABLE AND MORE RESISTANT TO MIXING AND THUS
SHOULD SEE LESS SUNSHINE) TO AROUND 80-82 EAST OF HIGHWAY 1... WITH
MOSTLY CLOUDY SKIES. MILD LOWS TONIGHT OF 67-71... AROUND 10 DEG
ABOVE NORMAL. -GIH
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
AS OF 330 AM MONDAY...
CONTINUED MOIST WITH A GOOD CHANCE OF SHOWERS... AND PERHAPS A STORM
OR TWO. THE MID LEVEL TROUGH FROM THE LOWER GREAT LAKES THROUGH THE
LOWER MISS VALLEY TO LA WILL CONTINUE TO TILT SLOWLY... RESULTING IN
A GRADUAL INCREASE IN MID LEVEL VORTICITY MOVING FROM THE NW GULF
INTO THE CAROLINAS ON WEAK SOUTHWESTERLY MID LEVEL FLOW. THE LOW
LEVEL ATLANTIC INFLOW SHOULD BE ON THE DECREASE WITH A REDUCED
FETCH... A FUNCTION OF WHAT IS NOW TD #11 AS IT PUSHES SLOWLY NW/NNW
ON ITS ANTICIPATED TRACK TOWARD THE OFFSHORE WATERS OF NC. PW IS
PROJECTED TO REMAIN VERY HIGH AT 2.0-2.3 INCHES... WELL ABOVE
SEASONAL NORMALS... AND MODELS SHOW SLIGHTLY BETTER POTENTIAL FOR
INSTABILITY TUE AFTERNOON WITHIN PERSISTENT HIGH THETA-E ADVECTION
IN THE LOW LEVELS. DESPITE THE WEAK WIND FIELD AND MARGINAL DPVA...
WE SHOULD SEE DECENT UPPER DIVERGENCE OVER THE AREA IN THE LEFT EXIT
REGION OF THE BROAD JET FROM THE GULF INTO THE TN VALLEY. WILL TREND
POPS UP TO LIKELY OVER MUCH OF THE CWA BY AFTERNOON... WANING
GRADUALLY IN THE EVENING/NIGHTTIME BUT STAYING AT 30-50%... WITH
BETTER SHOWER CHANCES SHIFTING WNW INTO THE NW PIEDMONT AND
FOOTHILLS WITH TIME. SLIGHTLY BETTER CAPE AND SHEAR ARE EXPECTED...
STILL MARGINAL THOUGH... SO HAVE INCLUDED JUST A MENTION OF ISOLATED
THUNDER IN THE AFTERNOON. HIGHS 75-83 AND LOWS 66-71... BOTH ABOVE
NORMAL... WITH MOSTLY CLOUDY SKIES HOLDING FIRM. -GIH
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 327 AM MONDAY...
UNCERTAINTY IN THE FORECAST IS ABOUT AS HIGH AS CAN BE ADVERTISED
FROM MID WEEK INTO THE WEEKEND. THE OPERATIONAL MODELS CONTINUE TO
SHOW PLENTY OF SPREAD AND EVEN THE ENSEMBLE MEANS ARE CONFLICTING ON
THE PLACEMENT OF THE IMPORTANT WEATHER PRODUCING SYSTEMS. THE MAIN
WEATHER HAZARDS SHOULD BE LIMITED TO A LOW END HEAVY RAIN THREAT...
BUT SIGNIFICANT RAINFALL MAY BE MORE OF A HELP TO CURRENT DROUGHT
STATUS THAN IT WOULD BE A THREAT FOR FLOODING. THE QPF MID TO LATE
WEEK IS THE MAIN QUESTION AS ABOUT 30 PERCENT OF THE MODELS INDICATE
THE HEAVIEST RAIN INLAND WITH OVERRUNNING RAINS AGAIN THU NIGHT INTO
SATURDAY... WHICH 70 PERCENT OF THE MODELS SUPPORT THE HEAVY SWATH
OF QPF ALONG OR JUST OFF THE MID-ATLANTIC COAST.
ONE THING SEEMS TO BE MORE CERTAIN SHOULD BE THE COOLER TEMPERATURES
AGAIN AS ANOTHER STRONG SURFACE HIGH IS EXPECTED TO BUILD SOUTH INTO
NC/SC THURSDAY INTO THE WEEKEND. THIS OCCURS AS A TROUGH ALOFT AND
LINGERING LOW LEVEL BOUNDARY CONTINUE TO BE FORECAST BY MOST MODELS
TO BRING A CONTINUATION OF THE UNSETTLED PATTERN THAT BEGAN LATE
LAST WEEK. A RETURN TO A PROLONGED NE FLOW... CONSIDERABLE
CLOUDINESS... AND POSSIBLY SIGNIFICANT RAIN IS EXPECTED THU-SAT.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 115 AM MONDAY...
MOIST AND DEEP LOW LEVEL FLOW FROM THE EAST WILL CONTINUE TO BRING
MOSTLY ADVERSE AVIATION CONDITIONS TODAY... ESPECIALLY AT INT/GSO...
WHERE IFR/LIFR CIGS AND MVFR/IFR VSBYS ARE LIKELY TO HOLD THROUGH
13Z... ALONG WITH PATCHY DRIZZLE. FARTHER EAST AT RDU/RWI/FAY...
MVFR CIGS SHOULD HOLD THROUGH 13Z... ALTHOUGH RWI MAY BREAK OUT TO
VFR FOR A SHORT TIME... AND RDU COULD DROP TO IFR IN THE PREDAWN
HOURS. SOON AFTER 13Z... CIGS AT ALL LOCATIONS SHOULD START TO
SLOWLY LIFT TO MVFR... LASTING UNTIL AROUND 18Z OR 19Z WHEN SOME
BREAKS IN THE CLOUDS ARE EXPECTED... ALTHOUGH ANY SCT/BKN CLOUDS ARE
STILL LIKELY TO BE BASED AT 2500-3000 FT AGL. A TREND BACK TO MVFR
TO IFR CIGS IS EXPECTED BY MID EVENING (AFTER 00Z TUE). THE LLWS
THREAT OF PREVIOUS NIGHTS IS MUCH LOWER AS THE EASTERLY WINDS JUST
OFF THE SURFACE (AT 1000-2000 FT AGL) HAVE WEAKENED. A FEW SHOWERS
ARE POSSIBLE THIS AFTERNOON AND COULD PRODUCE A PERIOD OF SUB-VFR
VSBYS.
LOOKING BEYOND 06Z TUE: IFR CONDITIONS ARE EXPECTED TO RULE
OVERNIGHT THROUGH DAYBREAK TUE... ALTHOUGH RWI MAY STAY MVFR FOR
MUCH OF THE NIGHT WITH PATCHY FOG. INT/GSO SHOULD STAY IFR OR MVFR
THROUGH TUE BUT RDU/RWI/FAY SHOULD LIFT TO MVFR THEN PERHAPS LOW-END
VFR TUE AFTERNOON. IFR/LIFR CONDITIONS IN FOG ARE EXPECTED TO RETURN
LATE TUE EVENING THROUGH DAYBREAK WED. VFR CONDITIONS THROUGH MIDDAY
WED BUT SHOWERS AND STORMS AHEAD OF A COLD FRONT MAY BRING SUB-VFR
CONDITIONS WED/WED NIGHT. THIS FRONT WILL MOVE THROUGH WED NIGHT AND
STALL TO OUR SE INTO FRI... POTENTIALLY BRINGING A RETURN TO
PREDOMINANTLY POOR AVIATION CONDITIONS WITHIN AREAS OF RAIN/DRIZZLE.
-GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...BADGETT
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1236 AM EDT MON SEP 28 2015
.SYNOPSIS...
A COASTAL TROUGH WILL WEAKEN AND DISSIPATE TODAY. A FRONT WILL
REACH THE AREA ON WEDNESDAY AND THEN STALL JUST OFFSHORE. DEEP
MOISTURE STREAMING NORTH FROM THE GULF OF MEXICO MAY BRING A
WIDESPREAD RAIN EVENT TO THE AREA LATE TUESDAY THROUGH THURSDAY.
LOW PRESSURE DEVELOPING OFFSHORE MAY CREATE MORE UNSETTLED
WEATHER FRIDAY AND SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1230 AM MONDAY...IMPRESSIVE CONVERGENCE BAND NEAR CAPE FEAR
CONTINUES TO FEED SHOWERS WESTWARD ALONG THE BRUNSWICK COUNTY
COAST TO JUST NORTH OF MYRTLE BEACH. LATEST HRRR MODEL INDICATES
THIS FEATURE MAY BE WITH US FOR ANOTHER 3-5 HOURS...SO FORECAST
POPS HAVE BEEN RAISED TO 60-80 PERCENT FROM SOUTHPORT THROUGH
LITTLE RIVER. OTHERWISE...NO SIGNIFICANT CHANGES WERE MADE TO THE
FORECAST AT THIS TIME. DISCUSSION FROM 1000 PM SUNDAY FOLLOWS...
RADAR CONTINUES TO SHOW SCATTERED SHOWERS MOVING ONSHORE IN
EASTERLY FLOW. TENDENCY THIS EVENING HAS BEEN FOR THEM TO WEAKEN
AS THEY MOVE ON THE COAST AND COVERAGE HAS BEEN ON A SLOW DOWN
TREND. HAVE TRENDED POPS BACK TOWARD CHANCE/SLIGHT CHANCE
CATEGORIES FOR MUCH OF THE NIGHT WITH LOWS INVOF 70 UNDER A MAINLY
CLOUDY SKY.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY NIGHT/...
AS OF 300 PM SUNDAY...A COASTAL TROUGH WILL REMAIN IN CLOSE
PROXIMITY AND MAY EVEN MOVE ONSHORE FOR A TIME ON MON BEFORE FINALLY
LIFTING OUT DURING TUE. VERY HIGH PRECIPITABLE WATER VALUES...99TH
PERCENTILE...REMAIN ACROSS THE AREA ON MON WITH SOME SLIGHT DRYING
ON TUE AS THE PREVAILING LOW-LEVEL FLOW...WHICH HAS BEEN EASTERLY
FOR DAYS...BECOMES SOUTH AND SOUTHWEST. NORMALLY...THIS WOULD SIGNAL
A CHANCE TO DRY OUT AND ALLOW FOR MORE IN THE WAY OF SUNSHINE.
HOWEVER...DEEP MOISTURE FROM THE GULF OF MEXICO WILL BE STREAMING
NORTHWARD AS TROPICAL LOW PRESSURE MAKES A RUN FOR THE NE GULF
COAST. THIS MAY NECESSITATE EVEN HIGHER POPS FOR TUE THAN ON
MON AND OVER THE ENTIRE FORECAST AREA.
THUS...WILL BE KEEPING POPS ELEVATED AND AS HIGH AS LIKELY AND
INCLUDE A MENTION OF ISOLATED THUNDERSTORMS TUE/TUE NIGHT AS
MIXED LAYER CAPE VALUES BEGIN TO INCREASE IN DEEPENING SW FLOW AND
WE BEGIN TO SEE SIGNIFICANT LIFT DEVELOP THROUGH A MUCH DEEPER
LAYER LATE IN PERIOD AND ON WED.
CONSIDERABLE CLOUD COVER WILL CONTINUE...ALTHOUGH FORESEE MORE IN
THE WAY OF BREAKS OF PARTIAL SUNSHINE DEVELOPING AS COMPARED TO
THE PAST SEVERAL DAYS AS WEDGE WEAKENS AND IS DISPLACED WESTWARD.
THEREFORE...TEMPS SHOULD BE CLOSER TO CLIMATOLOGY THROUGHOUT AND
WILL FORECAST MORE WIDESPREAD LOWER 80S FOR HIGHS BOTH DAYS. LOWS
MAINLY IN THE UPPER 60S TO AROUND 70...WHICH WILL BE SEVERAL DEGREES
ABOVE NORMAL.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AS OF 300 PM SUNDAY...THE MEDIUM RANGE FORECAST LOOKS TO BE
DOMINATED BY WEAK TROUGHING AT THE MID LEVELS ACROSS THE EASTERN
U.S. THE GUIDANCE IS WAVERING BETWEEN CLOSED LOW PRESSURE
DEVELOPING IN THE EAST OR WEAK TROUGHING. REGARDLESS AT THE
SURFACE...MASSIVE HIGH PRESSURE WILL DEVELOP WELL TO THE NORTHEAST
AND REMAIN ENTRENCHED ACROSS THE SOUTHEAST THROUGH SATURDAY.
LINGERING LOW PRESSURE WHICH NEVER GETS SWEPT OUT INTO THE
ATLANTIC RETROGRADES SLIGHTLY SATURDAY AND SUNDAY. THE HIGHEST
POPS OCCUR WEDNESDAY AS A 500MB TROUGH MOVES ACROSS PICKING UP
LINGERING MOISTURE AND DYNAMICS FROM THE GULF OF MEXICO. THE
ATTENDANT FRONT WILL MOVE SLOWLY ACROSS SLOWLY BY LATER THURSDAY
WITH SOME LINGERING DRIZZLE OR LIGHT RAIN THURSDAY INTO FRIDAY.
OVERALL THE TEMPERATURE FORECAST IS CHARACTERIZED BY LIMITED
DIURNAL RANGES WITH EXPECTED CLOUD COVER AND POSSIBLE SHOWERS AND
DRIZZLE.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 06Z...SHOWERS ARE STILL STREAMING ONSHORE JUST NORTH OF
MYRTLE BEACH AND THIS SHOULD CONTINUE THROUGH THE PRE-DAWN HOURS
THIS MORNING. WHERE CIGS ARE NOT IFR...THEY SHOULD DROP TO IFR
SHORTLY...REMAINING THERE THROUGH 13-15Z. COMPUTER MODELS INDICATE DRY
AIR ARRIVING IN THE MID LAYERS BY DAYBREAK...SO DO NOT THINK
SHOWERS WILL BE AS PREVALENT AFTER DAYBREAK. GOOD CHANCE FOR VFR
IN THE AFTERNOON...BUT RETURNING TO IFR TOWARD 06Z TUESDAY.
EXTENDED OUTLOOK...DETERIORATING CONDITIONS TUESDAY...WITH SHOWERS AND
INTERMITTENT IFR CONDITIONS THROUGH THE EXTENDED.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 AM MONDAY...BUMPED WIND SPEEDS UP TO 20-25 KT BASED ON
BUOY DATA AND WIND OBSERVATIONS FROM MERCER PIER AT WRIGHTSVILLE
BEACH AND A MESONET OBSERVATION FROM TOPSAIL BEACH. OTHERWISE NO
SIGNIFICANT CHANGES WERE MADE WITH THIS UPDATE. DISCUSSION FROM
1000 PM SUNDAY FOLLOWS...
SMALL CRAFT ADVISORY FOR NORTHERN WATERS AMZ250...CONTINUED INTO
EARLY MON MORNING WITH HIGHEST SEAS IN THE NORTHERN OUTER WATERS.
SCEC WILL CONTINUE CAPE FEAR TO LITTLE RIVER FORE SEAS INVOF 5 FT
AT 20 NM. WHILE 15 TO 20 KT WINDS ARE POSSIBLE NORTHERN WATERS
UNTIL AROUND MIDNIGHT...NE WINDS SHOULD DIMINISH TO 10 TO 15 KT
OVER ALL WATERS BY DAYBREAK. SEAS SHOULD FALL BELOW SCA OR SCEC
LEVELS LATE TONIGHT OR EARLY MONDAY.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 300 PM SUNDAY...PERSISTENT COASTAL TROUGH WILL BE IN PLACE
MON THEN SLOWLY LIFT OUT DURING TUE. THE EASTERLY FLOW AROUND
STRONG NEW ENGLAND HIGH PRESSURE LOOKS LIKE IT SHOULD WEAKEN MON AS
THE TIGHTER PRESSURE GRADIENT PROPAGATES NORTH. THE LOW-LEVEL FLOW
IS EXPECTED TO BECOME MORE SOUTHERLY DURING TUE AND TUE NIGHT...BUT
THE FLOW WILL BE WEAK. THE 10 TO 11 SECOND EASTERLY SWELL WILL
REMAIN SIGNIFICANT INTO TUE AND THIS WILL KEEP SEAS ELEVATED.
HOWEVER...THE WEAKER WINDS SHOULD ALLOW SEAS TO DROP ABOUT A FOOT OR
SO. WIND SPEEDS THROUGH THE PERIOD WILL BE 10 KT OR LESS. SEAS UP TO
4 TO 5 FT ACROSS THE NORTHERN WATERS AND 3 TO 4 FT ACROSS THE
SOUTHERN WATERS MON WILL DROP TO 2 TO 4 FT THROUGHOUT BY TUE.
LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 300 PM SUNDAY...LIGHT WIND FIELDS EARLY ON WILL GIVE WAY TO
A BETTER DEFINED NORTHEAST FLOW LATE WEDNESDAY. ESSENTIALLY LIGHT
AND VARIABLE WINDS THROUGH EARLY AFTERNOON WEDNESDAY BEFORE A
FRONT CROSSES THE WATERS. BEYOND THIS A NORTHEAST FLOW OF 10-15
KNOTS DEVELOPS AND STRENGTHENS TO 15-20 BY THURSDAY. THIS WILL
CONTINUE INTO FRIDAY. SIGNIFICANT SEAS WILL INCREASE FROM 2-4 FEET
WEDNESDAY TO 4-7 FEET LATER THURSDAY AND CONTINUE THROUGH THE DAY
FRIDAY.
&&
.TIDES/COASTAL FLOODING...
AS OF 300 PM SUNDAY...A COASTAL FLOOD ADVISORY WILL BE ISSUED FOR
A FEW HOURS THIS EVENING SURROUNDING PERIOD OF THE HIGH TIDE. THIS
WILL IMPACT THE BEACHES FROM SURF CITY TO THE SOUTH SANTEE RIVER
AND ALONG THE CAPE FEAR RIVER IN DOWNTOWN WILMINGTON. PERSISTENT
ON SHORE WINDS AND LONG PERIOD EASTERLY SWELLS ALONG WITH HIGH
ASTRONOMICAL TIDES HAVE RAISED TIDAL LEVELS TO GREATER THAN A FOOT
ABOVE NORMAL. WE CAN EXPECT THIS TO PERSIST AT LEAST THROUGH THE
NEXT DAY OR SO...BUT SLOWLY WANE AS WE PASS THE FULL MOON TONIGHT.
THE NEXT HIGH TIDE FOR LOCAL BEACHES WILL BE BETWEEN 7 AND 8 PM
THIS EVENING AND FOR THE CAPE FEAR RIVER IT WILL OCCUR AROUND 10
PM. THIS WILL COINCIDE VERY CLOSELY WITH THE FULL MOON AT 1050 PM
THIS EVENING. THERE IS ALSO A HIGH RISK OF RIP CURRENTS FOR PENDER
AND NEW HANOVER COUNTY BEACHES INTO TONIGHT AND FOR ALL BEACHES
ON MONDAY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...HIGH RIP CURRENT RISK FROM 8 AM EDT THIS MORNING THROUGH THIS
EVENING FOR SCZ054-056.
NC...HIGH RIP CURRENT RISK FROM 8 AM EDT THIS MORNING THROUGH THIS
EVENING FOR NCZ106-108-110.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT EARLY THIS MORNING FOR
AMZ250.
&&
$$
SYNOPSIS...
NEAR TERM...TRA
SHORT TERM...RJD
LONG TERM...SHK
AVIATION...TRA/DL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1008 AM EDT MON SEP 28 2015
.SYNOPSIS...
HIGH PRESSURE CENTERED OFF THE NEW ENGLAND COAST WILL PUSH OUT TO
SEA TODAY...WHILE MOISTURE INCREASES AND AN UPPER LEVEL
DISTURBANCE FOCUSES SCATTERED SHOWERS ACROSS MAINLY THE WESTERN
HALF OF PENNSYLVANIA. A COLD FRONT WILL PUSH SOUTH ACROSS
PENNSYLVANIA LATE TUESDAY...THEN STALL OUT SOUTH OF THE STATE.
TROPICAL MOISTURE WILL FOCUS ON THE FRONT AND BRING A SOAKING RAIN
TO MUCH OF CENTRAL AND EASTERN PENNSYLVANIA TUESDAY NIGHT THROUGH
WEDNESDAY NIGHT. UNSETTLED CONDITIONS WILL PREVAIL FOR THE
REMAINDER OF THE WEEK...AS A SLOW MOVING COASTAL LOW AFFECTS
PORTIONS OF THE MID ATLANTIC REGION LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SHEARING 5H TROF LIFTING OVER THE WESTERN PERIPHERY OF THE
RETREATING OFFSHORE 5H RIDGE AND ASSOCIATED 850 MB
CONVERGENCE ZONE COINCIDENT WITH 25-30KT JET AND PW POOLING TO
1.5" WILL CONTINUE TO FOCUS SHOWERS INTO THIS AFTERNOON ACROSS
WESTERN AND CENTRAL PORTIONS. EARLIER HI RES HRRR WAS NOT HANDLING
THIS FORCING AND SHOWERS ADEQUATELY AS IT PROPOGATES
EASTWARD...BUT HAS NOW CAUGHT UP TO CURRENT RADAR TRENDS. BUMPED
POPS AND QPF UPWARD FOR THE CENTRAL AND NORTH CENTRAL MOUNTAINS
THROUGH THIS AFTERNOON AS A RESULT. MOST AREAS WILL SEE LESS THAN
A TENTH OF AN INCH OVER THE CENTRAL MOUNTAINS...WITH LOCALLY ONE
TO TWO TENTHS TOTAL FROM THE LAUREL HIGHLANDS INTO THE WEST
CENTRAL MOUNTAINS. THE SHOWERS WILL SLOWLY PROPOGATE EASTWARD
THROUGHOUT THE AFTERNOON AS THE UPPER RIDGE IS DISPLACED
EASTWARD.
THE MOIST SERLY LLVL FLOW AND OROGRAPHIC LIFT WILL KEEP CLOUDY SKIES
OVER ALL OF CENTRAL PA. HIGHS WILL RANGE FROM THE MID TO UPPER
60S OVR THE ALLEGHENY PLATEAU TO THE U70S SOUTHEAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
WEAK FORCING...AS INFERRED BY MDL 500-300MB QVEC DIV FIELDS...SHOULD
RESULT IN LITTLE IF ANY RAIN TONIGHT...DESPITE POSITIVE PWAT
ANOMALIES OF 2SD PER LATEST GEFS. CLOUD COVER AND SURGING DWPT
WILL TRANSLATE TO A MILD NIGHT FOR LATE SEPT...WITH MINS BTWN
60-65F.
A MORE SIG SHORTWAVE WILL PUSH SE INTO THE GRT LKS ON
TUESDAY...PUSHING A COLD FRONT TOWARD NW PA BY LATE IN THE DAY.
DEEP SOUTHERLY FLOW AND SURGING PWATS...COMBINED W/APPROACH OF
SHORTWAVE...SHOULD PROMOTE NUMEROUS SHRA/TSRA...ESP DURING THE PM
HOURS. BASED ON LATEST ENSEMBLE OUTPUT...HAVE RAISED POPS ACROSS
THE BOARD. DESPITE OVERCAST SKIES...TEMPS SHOULD AGAIN BE SEVERAL
DEG ABV AVERAGE WITH MID SUMMER-LIKE DWPTS MAKING IT FEEL EVEN
WARMER.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
INCREASING CONFIDENCE IN SIG RAINFALL ACROSS PARTS OF CENTRAL PA
TUES NIGHT/WED...AS SLOW-MOVING COLD FRONT INTERACTS WITH PLUME
OF TROPICAL MOISTURE. PWATS NR 3SD ABV NORMAL...COMBINED WITH
MDL INSTABILITY AND SLOW MOVING FRONT SUPPORT THE IDEA OF FAIRLY
WIDESPREAD 1+ INCH AMTS...WITH MUCH HIGHER LOCALIZED AMTS. GIVEN
THE RECENT DRYNESS...WIDESPREAD FLOODING NOT A CONCERN. HOWEVER...WILL
MENTION POTENTIAL OF LOCALIZED FLOODING IN THE HWO.
CONFIDENCE IN LINGERING WET WX APPEARS TO BE INCREASING ACROSS
CENTRAL PA LATE THIS WEEK...AS ALL MDLS HAVE CONVERGED ON IDEA OF
A CUT OFF LOW FORMING OVR THE OHIO VALLEY WITH ASSOC SFC LOW CRAWLING
UP THE MID ATL COAST. HAVE INCREASED POPS IN THE THU-SAT TIME
FRAME...WITH THE HIGHEST POPS ACROSS THE SOUTHEAST COUNTIES.
AFTER A VERY MILD MON-TUE...NORTHERLY FLOW/LOW LVL CAA IN WAKE OF
COLD FRONT...COMBINED WITH POSSIBLE RAIN...SHOULD TRANSLATE TO
TEMPS BLW CLIMO LATE NEXT WEEK...ESP DURING THE DAYTIME.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
WIDESPREAD IFR/AREAS MVFR COVERING CENTRAL PA THIS MORNING INTO
THIS AFTERNOON AS LOW LEVEL MOISTURE IN THE LOWEST 5KFT AGL
CONTINUES TO INCREASE ON SOUTHERLY FLOW.
THESE RESTRICTIONS WILL REMAIN IN PLACE THE MAJORITY OF THE
DAY...ESP WEST WHERE A RELATIVELY SHORT PERIOD OF MVFR CIGS POSS
IN THE AFTERNOON. THE LOWER SUSQ WILL IMPROVE MORE
DRAMATICALLY...LIKELY REACHING VFR FOR A GOOD PORTION OF THE
AFTERNOON. NUMEROUS -SHRA WILL AFFECT PRIMARILY THE WESTERN HALF OF
CWA.
SURFACE WINDS WILL BE FROM THE EAST TO SOUTHEAST AT SPEEDS OF
GENERALLY 5-10MPH.
LOW CIGS REDEVELOP AREAWIDE OVERNIGHT...WITH WIDESPREAD IFR
REDUCTIONS. LOWER CIGS CONTINUE INTO TUE...WITH AREA OF SHOWERS
MOVING IN.
OUTLOOK...
TUE...LOW CIGS/SHOWERS LIKELY...ESP NW HALF.
TUE NIGHT...LOW CIGS/SCT SHOWERS.
WED...LOW CIGS NW MTNS EARLY. CHC SHOWERS SOUTH.
THU...NO SIG WX.
FRI...CHC OF SHOWERS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD
AVIATION...DEVOIR/RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
327 AM EDT MON SEP 28 2015
.SYNOPSIS...
HIGH PRESSURE IS OFF THE COAST AND WINDS ARE MORE SOUTHERLY. A
COLD FRONT WILL PUSH SOUTH ACROSS PENNSYLVANIA LATE TUESDAY...THEN
STALL OUT SOUTH OF THE STATE. A SLOW MOVING COASTAL LOW WILL
AFFECT PORTIONS OF THE MID ATLANTIC REGION LATE IN THE WEEK.
COOLER TEMPERATURES WILL PREVAIL FOR THE SECOND PART OF THE WEEK.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
WEAK SHORTWAVE RIDING ACROSS THE GRT LKS IS SUPPORTING AN AREA OF
RAIN ACROSS NW PA AT 06Z. RADAR TRENDS AND LATEST HRRR IMPLY THE
RAIN WILL TAPER OFF TOWARDS DAWN ACROSS THE NW COUNTIES...AS
SHORTWAVE LIFTS OUT. HOWEVER...PLUME OF ANOMALOUS PWATS WILL
REMAIN OVR THE WESTERN HALF OF THE STATE...SUPPORTING THE CHC OF
LINGERING SHOWERS ACROSS THE NW MTNS THRU MID MORNING AND SPOTTY
DRIZZLE WHERE MOIST SE FLOW ASCENDS THE LAUREL HIGHLANDS.
WILL MAINTAIN A DRY OVERNIGHT FCST ACROSS THE EASTERN HALF OF THE
STATE...WHERE SFC RIDGE AND LOWER PWAT AIR MASS WILL LIE. MAINLY
OVERCAST SKIES AND INCREASING LOW LVL MOISTURE WILL TRANSLATE TO A
MILDER NIGHT THAN LAST NIGHT WITH MIN TEMPS BTWN 55-60F.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH 6 PM TUESDAY/...
OFFSHORE HIGH RETREATS FARTHER OFFSHORE ON MONDAY...WITH EASTERLY
FETCH DECREASING AS A RESULT. DEEP LAYER MOISTURE PLUME INCREASES
OVER PA AS A RESULT OF THE AMPLIFIED SOUTHERLY FLOW ALOFT. FORCING
REMAINS WEAK ON MONDAY...BUT THE SERLY LOW LVL FLOW AND ASSOC
OROGRAPHIC FORCING WILL KEEP THINGS CLOUDY FOR MOST. WEAK UPPER
TROF LIFTING THRU WILL PRODUCE SCT SHOWERS...ESP ACROSS THE WEST.
HIGHS WILL RANGE FROM THE MID TO UPPER 60S OVR THE ALLEGHENY
PLATEAU TO THE U70S SOUTHEAST.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
MID SHIFT DID EDGE POPS UP SOME FOR THE LATER PART OF THE
WEEK. THUS DID NOT MAKE ANY LARGE CHANGES TO THIS PART OF
THE FCST.
MAIN CHANGE WAS TO EDGE POPS DOWN JUST A LITTLE ON THE WESTERN
AND NORTHERN EDGES.
FIRST PROBLEM IS THE COLD FRONT FOR LATE TUE. DID UP POPS TO
LIKELY. AS NOTED YESTERDAY...KEY TO FCST THE RATHER DRY AIR
BEING ADVECTED INTO THE AREA THE LAST FEW DAYS. ANYWAY...NOT SOLD
ON A LOT OF RAIN. MODELS HINT AT SOME MODERATE QPF. WILL HAVE TO
ADVECT HIGHER DEWPOINT/PW AIR IN FROM THE SE COAST TO GET MUCH
RAIN. LEFT THUNDER OUT FOR NOW.
LATER WED AND THU STILL LOOK MAINLY DRY.
FOR FRIDAY AND SAT...MODELS SHOW A LOW BACKING IN FROM THE
COAST...AND A STRONG EASTERLY FLOW BETWEEN A LARGE HIGH OVER
EASTERN CANADA AND THE LOW TO THE SOUTH. LOOKS LIKE THE MODELS TRY
TO PHASE THE LONGWAVE ENERGY WITH A WARM CORE LOW. A LOT OF SPREAD
IN SOLUTIONS FROM DAY TO DAY.
LOOKS LIKE THE TIMING WOULD TAKE THE BULK OF THE RAIN TO THE NE
BY LATER SAT. FOR NOW...LEFT SUNDAY DRY.
NOT LOOKING AT FROST AT THIS POINT...BUT SOME RATHER COLD
AIR WELL NORTH OF PA WITH SFC HIGH.
ALTHOUGH MUCH UNCERTAINTY REMAINS WITH REGARDS TO LATE WEEK
RAIN...THERE IS A GOOD DEAL OF CONFIDENCE IN TEMPS TAKING TUMBLE
AFTER A VERY MILD MON-TUE. NORTHERLY FLOW/LOW LVL CAA IN WAKE OF
COLD FRONT...COMBINED WITH POSSIBLE RAIN...SHOULD TRANSLATE TO
TEMPS AOB CLIMO LATE NEXT WEEK...ESP DURING THE DAYTIME.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
LLVL MOISTURE WILL SLOWLY INCREASE OVERNIGHT THROUGH THE DAY
MONDAY AS THE FLOW CONTINUES TO BECOME MORE SOUTHERLY IN THE
LOWEST 5KFT AGL. A LAYER OF DRY AIR WILL REMAIN ABOVE THAT.
RESTRICTIONS FROM AN EXPANDING/LOWERING DECK OF STRATOCU AND
STRATUS IMPACTING ALL OF CENTRAL PA AT 07Z. THE CLOUDS WILL
CONTINUE TO GRADUALLY LOWER FROM SW TO NE OVERNIGHT...WITH MOST
NUMEROUS -SHRA AFFECTING PRIMARILY THE NW THIRD OF CWA...WITH MORE
ISOLATED -SHRA DRIFTING ACROSS THE SW.
AREAS OF IFR CIGS /WITH SOME DRIZZLE OR SCATTERED -SHRA/ WILL
OCCUR ACROSS THE CENTRAL AND WRN MTNS OF PENN LATE TONIGHT AND
MONDAY MORNING...ESPECIALLY INVOF KJST WHERE THE SERLY LLVL
UPSLOPE FLOW IS MAXIMIZED.
SURFACE WINDS WILL BE FROM THE EAST TO SOUTHEAST AT SPEEDS OF
GENERALLY 5-10MPH.
LOW CIGS PERSIST INTO MON...WITH BEST CHANCE FOR IMPROVEMENT
BEING OVER THE LOWER SUSQ. CONDITIONS COULD STAY IN THE
LOW MVFR /OR EVEN UPPER IFR/ RANGE FOR MUCH OF THE DAY ACROSS NW
HALF OF OUR FCST AREA WITH LIGHT RAIN SHOWERS AROUND.
OUTLOOK...
MON...INCREASING LIKELIHOOD OF LIGHT RAIN/LOW CIGS...FOCUSED
MAINLY ACROSS WESTERN MTNS OF PENN.
TUE...LOW CIGS/SHOWERS LIKELY...ESP NW HALF.
TUE NIGHT...LOW CIGS/SCT SHOWERS.
WED...LOW CIGS NW MTNS EARLY. CHC SHOWERS SOUTH.
THU...NO SIG WX.
FRI...CHC OF SHOWERS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR/MARTIN
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...FITZGERALD/MARTIN
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
220 AM EDT MON SEP 28 2015
.SYNOPSIS...
HIGH PRESSURE IS OFF THE COAST AND WINDS ARE MORE-SOUTHERLY. A
COLD FRONT WILL PUSH SOUTH ACROSS PENNSYLVANIA LATE TUESDAY...THEN
STALL OUT SOUTH OF THE STATE. A SLOW MOVING COASTAL LOW WILL
AFFECT PORTIONS OF THE MID ATLANTIC REGION LATE IN THE WEEK.
COOLER TEMPERATURES WILL PREVAIL FOR THE SECOND PART OF THE WEEK.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
WEAK SHORTWAVE RIDING ACROSS THE GRT LKS IS SUPPORTING AN AREA OF
RAIN ACROSS NW PA AT 06Z. RADAR TRENDS AND LATEST HRRR IMPLY THE
RAIN WILL TAPER OFF TOWARDS DAWN ACROSS THE NW COUNTIES...AS
SHORTWAVE LIFTS OUT. HOWEVER...PLUME OF ANOMALOUS PWATS WILL
REMAIN OVR THE WESTERN HALF OF THE STATE...SUPPORTING THE CHC OF
LINGERING SHOWERS ACROSS THE NW MTNS THRU MID MORNING AND SPOTTY
DRIZZLE WHERE MOIST SE FLOW ASCENDS THE LAUREL HIGHLANDS.
WILL MAINTAIN A DRY OVERNIGHT FCST ACROSS THE EASTERN HALF OF THE
STATE...WHERE SFC RIDGE AND LOWER PWAT AIR MASS WILL LIE. MAINLY
OVERCAST SKIES AND INCREASING LOW LVL MOISTURE WILL TRANSLATE TO A
MILDER NIGHT THAN LAST NIGHT WITH MIN TEMPS BTWN 55-60F.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH 6 PM TUESDAY/...
OFFSHORE HIGH RETREATS FARTHER OFFSHORE ON MONDAY...WITH EASTERLY
FETCH DECREASING AS A RESULT. DEEP LAYER MOISTURE PLUME INCREASES
OVER PA AS A RESULT OF THE AMPLIFIED SOUTHERLY FLOW ALOFT. FORCING
REMAINS WEAK ON MONDAY...BUT THE SERLY LOW LVL FLOW AND ASSOC
OROGRAPHIC FORCING WILL KEEP THINGS CLOUDY FOR MOST. WEAK UPPER
TROF LIFTING THRU WILL PRODUCE SCT SHOWERS...ESP ACROSS THE WEST.
HIGHS WILL RANGE FROM THE MID TO UPPER 60S OVR THE ALLEGHENY
PLATEAU TO THE U70S SOUTHEAST.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
MID SHIFT DID EDGE POPS UP SOME FOR THE LATER PART OF THE
WEEK. THUS DID NOT MAKE ANY LARGE CHANGES TO THIS PART OF
THE FCST.
MAIN CHANGE WAS TO EDGE POPS DOWN JUST A LITTLE ON THE WESTERN
AND NORTHERN EDGES.
FIRST PROBLEM IS THE COLD FRONT FOR LATE TUE. DID UP POPS TO
LIKELY. AS NOTED YESTERDAY...KEY TO FCST THE RATHER DRY AIR
BEING ADVECTED INTO THE AREA THE LAST FEW DAYS. ANYWAY...NOT SOLD
ON A LOT OF RAIN. MODELS HINT AT SOME MODERATE QPF. WILL HAVE TO
ADVECT HIGHER DEWPOINT/PW AIR IN FROM THE SE COAST TO GET MUCH
RAIN. LEFT THUNDER OUT FOR NOW.
LATER WED AND THU STILL LOOK MAINLY DRY.
FOR FRIDAY AND SAT...MODELS SHOW A LOW BACKING IN FROM THE
COAST...AND A STRONG EASTERLY FLOW BETWEEN A LARGE HIGH OVER
EASTERN CANADA AND THE LOW TO THE SOUTH. LOOKS LIKE THE MODELS TRY
TO PHASE THE LONGWAVE ENERGY WITH A WARM CORE LOW. A LOT OF SPREAD
IN SOLUTIONS FROM DAY TO DAY.
LOOKS LIKE THE TIMING WOULD TAKE THE BULK OF THE RAIN TO THE NE
BY LATER SAT. FOR NOW...LEFT SUNDAY DRY.
NOT LOOKING AT FROST AT THIS POINT...BUT SOME RATHER COLD
AIR WELL NORTH OF PA WITH SFC HIGH.
ALTHOUGH MUCH UNCERTAINTY REMAINS WITH REGARDS TO LATE WEEK
RAIN...THERE IS A GOOD DEAL OF CONFIDENCE IN TEMPS TAKING TUMBLE
AFTER A VERY MILD MON-TUE. NORTHERLY FLOW/LOW LVL CAA IN WAKE OF
COLD FRONT...COMBINED WITH POSSIBLE RAIN...SHOULD TRANSLATE TO
TEMPS AOB CLIMO LATE NEXT WEEK...ESP DURING THE DAYTIME.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
LLVL MOISTURE WILL SLOWLY INCREASE OVERNIGHT...THROUGH THE DAY
MONDAY AS THE FLOWS GRADUALLY VEERS FROM FROM EASTERLY TO
SOUTHERLY WITHIN ABOUT THE LOWEST 5 KFT AGL. THIS WILL MAINTAIN
LAYERS OF DRY AIR ABOVE THE OTHERWISE EXPANDING/LOWERING DECK OF
STRATO CU AND STRATUS.
THE CURRENT MAINLY MVFR STRATO CU/STRATUS DECK EXTENDING FROM KBFD
TO KUNV AND KAOO HAS LOWERED TO IFR ACROSS THE LAUREL HIGHLANDS.
THE CLOUDS WILL CONTINUE TO GRADUALLY LOWER FROM SW TO NE
OVERNIGHT WITH ISOLATED TO SCATTERED -SHRA AFFECTING PRIMARILY THE
SWRN THIRD-HALF OF PENN.
AREAS OF IFR CIGS /WITH SOME DRIZZLE OR SCATTERED -SHRA/ WILL
OCCUR ACROSS THE CENTRAL AND WRN MTNS OF PENN LATE TONIGHT AND
MONDAY MORNING...ESPECIALLY INVOF KJST WHERE THE SERLY LLVL
UPSLOPE FLOW IS MAXIMIZED.
SURFACE WINDS WILL BE FROM THE EAST TO SOUTHEAST AT SPEEDS OF
GENERALLY 5-10MPH.
LOW CIGS PERSIST INTO MON...WITH BEST CHANCE FOR IMPROVEMENT
BEING OVER THE LOWER SUSQ. CONDITIONS COULD STAY IN THE
LOW MVFR /OR EVEN UPPER IFR/ RANGE FOR MUCH OF THE DAY ACROSS NW
HALF OF OUR FCST AREA WITH LIGHT RAIN SHOWERS AROUND.
OUTLOOK...
MON...INCREASING LIKELIHOOD OF LIGHT RAIN/LOW CIGS...FOCUSED
MAINLY ACROSS WESTERN MTNS OF PENN.
TUE...LOW CIGS/SHOWERS LIKELY...ESP NW HALF.
TUE NIGHT...LOW CIGS/SCT SHOWERS.
WED...LOW CIGS NW MTNS EARLY. CHC SHOWERS SOUTH.
THU...NO SIG WX.
FRI...CHC OF SHOWERS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR/MARTIN
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...FITZGERALD/MARTIN
AVIATION...LAMBERT/MARTIN
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
947 PM EDT TUE SEP 29 2015
.DISCUSSION...MAIN AREA OF SHOWERS WILL BE EXITING NE TN AND SW VA
BEFORE MIDNIGHT. AREA RADARS BACK UP THE LATEST RAP MODEL RUN...
WHICH DELAYS THE ONSET OF NEW SHOWERS UNTIL TOWARD 12Z WEDNESDAY.
THUS...I OPTED TO LOWER RAIN CHANCES FOR THE REST OF THE NIGHT.
ADJUSTED HOURLY TEMPS AND DEW POINT TEMPS...PLUS LOWERED MIN TEMP
GRID BY A COUPLE OF DEGREES. TOO CLOUDY OVERNIGHT FOR ANY
SIGNIFICANT AREAS OF FOG TO FORM.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 69 78 62 72 / 40 60 30 20
KNOXVILLE MCGHEE TYSON AIRPORT, TN 68 75 61 69 / 50 60 40 40
OAK RIDGE, TN 68 75 60 69 / 50 60 40 30
TRI CITIES AIRPORT, TN 65 73 59 65 / 70 60 60 50
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
TG
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
631 PM CDT TUE SEP 29 2015
.UPDATE...
SHORTWAVE LOCATED UPSTREAM THIS EVENING...BUT NO REAL ORGANIZATION
AS OF YET. MODELS IN AGREEMENT WITH THE AFOREMENTIONED FEATURE
MOVING OUR WAY OVERNIGHT. IN FACT...DEEPER MOISTURE EXPECTED TO
REACH ACROSS NORTHERN MIDDLE TN BY 12Z. HRRR CONFIRMS THIS AS
WELL. WILL GO AHEAD AND RAISE POPS/QPF FOR THE AFTER MIDNIGHT
PERIOD. ALSO...GIVEN THE EXPECTED LOW DEWPOINT DEPRESSIONS AND ISC
INFO...WILL GO AHEAD AND ADD PATCHY FOG. REMAINDER OF FCST IS IN
GOOD SHAPE.
&&
.PREV DISCUSSION... /ISSUED 254 PM CDT TUE SEP 29 2015/
DISCUSSION...
LIGHT TO MODERATE RAIN AND A FEW THUNDERSTORMS CONTINUE AT FORECAST
TIME...WITH THE BULK OF THE ACTIVITY OVER THE EASTERN HALF OF THE
MID-STATE. THE HEAVIER RAINS OVER THE PLATEAU WILL CONTINUE TO PUSH
OFF TO THE EAST OVER THE NEXT COUPLE OF HOURS...IN FACT...SOME OF
THE HI-RES GUIDANCE WOULD SUGGEST A LARGE DROP-OFF IN POP COVERAGE
IN THE NEXT 6 HOURS. WILL REDUCE POPS AS WE GO INTO THE OVERNIGHT
HOURS...ESPECIALLY FOR THE WESTERN HALF OF THE AREA. TEMPERATURES
SHOULD REMAIN FAIRLY FLAT WITH ONLY A 8-10 DEGREE DIURNAL COOL OFF
TONIGHT DUE TO THE PERSISTENT CLOUD COVER...AND WE SHOULD RUN A
COUPLE OF DEGREES ABOVE GUIDANCE FOR THIS REASON AS WELL.
UNFORTUNATELY WE AREN`T OUT OF THE WOOD REGARDING THE RAIN JUST YET.
ANOTHER WEAK SHORTWAVE IS EXPECTED TO PUSH THROUGH THE STATE ON
WEDNESDAY AND BRING ANOTHER SHOT OF RAIN. I DON`T THINK THE
COVERAGE WILL BE AS HIGH AS WE HAVE SEEN TODAY AND THE FOCUS FOR THE
HIGHEST CHANCES OF RAIN SHOULD REMAIN EAST OF I-65. THIS SHORTWAVE
WILL HOWEVER BE THE INSTIGATOR IN OUR TEMPERATURE DROP-OFF FOR THE
REST OF THE WEEK.
YESTERDAY I ELUDED TO THE DIFFERENCES IN THE GFS AND EURO IN THE
MEDIUM AND LONG RANGE GUIDANCE. IT SEEMS AS THOUGH THE GFS HAS
STARTED TO HEAD IN THE DIRECTION OF THE EURO...WHICH MEANS AT LEAST
SOME RAIN CHANCES MAY VERY WELL BE POSSIBLE AS WE GO INTO THURSDAY
AND FRIDAY. THIS IS DUE TO A CLOSED LOW DEVELOPING AND DIVING INTO THE
DEEP SOUTH THURSDAY NIGHT. WHILE WE PROBABLY WON`T CATCH THE BRUNT
OF THIS SYSTEM...BUT WE MIGHT VERY WELL FALL VICTIM TO THE THE
BACKSIDE OF IT...WHICH MEANS CONTINUED CLOUD COVER...LIGHT
RAIN/DRIZZLE AND A RELATIVELY SMALL DIURNAL CURVE EACH DAY THROUGH
FRIDAY.
TROPICAL STORM JOAQUIN IN THE ATLANTIC IS LIKELY GOING TO BE THE
WILD CARD IN ALL OF THIS. AS IT CHURNS OFF THE ATLANTIC COAST...IT
COULD PROVIDE A BLOCKING MECHANISM FOR THIS CLOSED UPPER LEVEL LOW
THURSDAY AND FRIDAY...AND IT WILL LIKELY BE THE CATALYST AS TO
WHETHER OR NOT WE CLEAR OUT SATURDAY OR SUNDAY. FOR NOW...WILL
CARRY A SLIGHT CHANCE OF LIGHT RAIN FOR THE PLATEAU THROUGH
SATURDAY...WITH ALL GUIDANCE SUGGESTING THINGS CLEARING OUT FOR
EVERYONE IN MIDDLE TENNESSEE BY SUNDAY.
NEEDLESS TO SAY...AS WEDNESDAY`S SHORTWAVE BRINGS IN COOLER
TEMPERATURES FOR THE END OF THE WEEK...THE MID-STATE IS GOING TO GET
A TASTE OF FALL. NORMAL HIGHS ARE IN THE UPPER 70S AND LOWS IN THE
MIDDLE 50S...AND WE WILL LIKELY BE WELL BELOW THAT ALL WEEKEND SO
BREAK OUT THE SWEATSHIRTS.
UNGER
AVIATION...
18Z TAF DISCUSSION.
VFR CIGS HAVE MOVED INTO KCKV AND KBNA...AND LOOK TO CONTINUE
THROUGH THE AFTERNOON. MVFR CIGS MAY POP BACK INTO THOSE TERMINALS
THIS AFTERNOON...BUT CIGS LOOK TO DROP BY LATER THIS EVENING
REGARDLESS. KCSV MAY GET TO VFR CIGS THIS AFTERNOON...BUT KEPT IN
MVFR CIGS FOR NOW. SOME MODELS ARE HINTING AT FOG OVERNIGHT...AND
POSSIBLY WITH MVFR/IFR CIGS. DROPPED VIS TO MVFR AT KCSV BUT KEPT
THE OTHER TERMINALS VFR FOR NOW. CHANCES FOR SHOWERS WILL
CONTINUE THROUGH THE TAF PERIOD FOR ALL TERMINALS.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 67 72 59 71 / 50 30 10 10
CLARKSVILLE 65 70 55 70 / 60 20 10 10
CROSSVILLE 65 71 57 64 / 70 60 30 20
COLUMBIA 67 73 58 72 / 40 50 10 10
LAWRENCEBURG 68 74 58 72 / 30 40 10 10
WAVERLY 66 71 57 71 / 50 30 10 10
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
624 AM CDT MON SEP 28 2015
.AVIATION UPDATE...
12Z TAFS...OVERCAST VFR CONDITIONS ARE EXPECTED TODAY WITH SCT
-SHRA DEVELOPING OVER THE AREA. A SURGE OF TROPICAL MOISTURE WILL
BRING WIDESPREAD SHOWERS TONIGHT INTO TUESDAY. CONDITIONS WILL
DETERIORATE TONIGHT WITH MAINLY MVFR BY 06Z AND MAINLY IFR
CIGS/VSBYS BY 10Z.
13
&&
.PREV DISCUSSION... /ISSUED 320 AM CDT MON SEP 28 2015/
SHORT TERM...IT WAS A MOSTLY CLOUDY AND MUGGY NIGHT ACROSS MID
TN...WITH A FEW LIGHT SHOWERS OVER THE PLATEAU. WX FEATURES WE
ARE WATCHING FOR THIS FORECAST INCLUDE AN UPPER LEVEL LOW
PRESSURE SYSTEM ALONG THE TX GULF COAST...AND A TROPICAL LOW
OVER THE GULF OF MEXICO. SATELLITE AND RADAR LOOPS SHOWED DEEP
TROPICAL MOISTURE AND SHOWERS STREAMING NORTHWARD FROM THE GULF.
FOR TODAY...CLOUDS WILL THICKEN AND THE COVERAGE OF SHOWERS
WILL INCREASE THROUGH THE DAY...ESPECIALLY FOR OUR SOUTHERN
COUNTIES. HIGHS WILL RANGE IN THE UPPER 70S TO LOWER 80S WITH
MUGGY DEW POINTS IN THE 60S.
FOR TONIGHT THROUGH TUESDAY...A SURGE OF DEEP TROPICAL MOISTURE
WILL PUSH INTO TN. PRECIPITABLE WATER VALUES WILL REACH AROUND 2
INCHES BY TUESDAY MORNING. AT THE SAME TIME...IMPULSES WILL LIFT
NORTHWARD AHEAD OF THE TX UPPER LEVEL LOW...AND A DISTURBANCE WILL
APPROACH FROM THE NORTHWEST. THE TROPICAL LOW WILL TRACK ACROSS
NORTH FL TOWARD THE CAROLINA COAST...BUT MOISTURE WITH THIS SYSTEM
WILL SPREAD WELL NWWD TO THE TN VALLEY. THESE INGREDIENTS WILL
LEAD TO WIDESPREAD SHOWERS AND A FEW THUNDERSTORMS LATE TONIGHT
THROUGH TUESDAY. AVERAGE RAINFALL AMOUNTS THROUGH TUESDAY ARE
EXPECTED TO RANGE FROM AROUND ONE HALF INCH OVER OUR NORTHWEST
COUNTIES TO MORE THAN 1 INCH OVER THE SOUTH. LOCALLY GREATER
AMOUNTS WITH HEAVY DOWNPOURS ARE LIKELY OVER THE SOUTH AND
PLATEAU AS WELL.
UPPER LEVEL WINDS WILL TURN NORTHWEST TUESDAY NIGHT INTO WEDNESDAY
WITH A COLD FRONT PASSAGE. THE COVERAGE AND INTENSITY OF SHOWERS
WILL DECREASE.
LONG TERM...COOLER AIR WILL MOVE IN FOR THE EXTENDED FORECAST.
OVERNIGHT LOWS WILL BE DIPPING INTO THE 50S WITH HIGHS MAINLY IN
THE UPPER 60S TO LOWER 70S...WHICH WOULD BE JUST A COUPLE OF
DEGREES COOLER THAN NORMAL. MODELS SUGGEST AN UPPER TROUGH WILL
LINGER...POSSIBLY KEEPING SOME SHOWERS AROUND FOR THE UPPER
CUMBERLAND REGION LATE WEEK THROUGH THE WEEKEND. ANOTHER SYSTEM
MAY BRING SCATTERED SHOWERS ACROSS THE AREA INTO EARLY NEXT
WEEK...BUT CONFIDENCE IS LOW REGARDING THE DETAILS.
13
PREV DISCUSSION... /ISSUED 1142 PM CDT SUN SEP 27 2015/
AVIATION UPDATE...
RAIN ACTIVITY HAS BEEN UNDERWHELMING THIS EVENING AND HRRR DOES
NOT PAINT A WET PICTURE FOR THE REST OF THE OVERNIGHT HOURS. TOOK
OUT VCSH AT ALL THREE TERMINALS UNTIL MORNING WHERE GUIDANCE BUMPS
POPS SLIGHTLY. BR WILL BE AN ISSUE AT CKV AND CSV OVERNIGHT. THE
MORE SIGNIFICANT OMEGA AND RAIN CHANCES WILL HOLD OFF UNTIL AFTER
THE END OF THE TAF PERIOD. WINDS WILL BE E/SE UNDER 5 KTS DURING
THE TAF PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 81 66 78 65 / 40 80 90 50
CLARKSVILLE 81 66 78 63 / 30 60 80 40
CROSSVILLE 77 64 74 63 / 30 80 100 60
COLUMBIA 80 65 79 65 / 40 80 90 50
LAWRENCEBURG 79 65 79 65 / 50 80 90 50
WAVERLY 81 65 79 64 / 30 70 80 40
&&
.OHX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
320 AM CDT MON SEP 28 2015
.SHORT TERM...IT WAS A MOSTLY CLOUDY AND MUGGY NIGHT ACROSS MID
TN...WITH A FEW LIGHT SHOWERS OVER THE PLATEAU. WX FEATURES WE
ARE WATCHING FOR THIS FORECAST INCLUDE AN UPPER LEVEL LOW
PRESSURE SYSTEM ALONG THE TX GULF COAST...AND A TROPICAL LOW
OVER THE GULF OF MEXICO. SATELLITE AND RADAR LOOPS SHOWED DEEP
TROPICAL MOISTURE AND SHOWERS STREAMING NORTHWARD FROM THE GULF.
FOR TODAY...CLOUDS WILL THICKEN AND THE COVERAGE OF SHOWERS
WILL INCREASE THROUGH THE DAY...ESPECIALLY FOR OUR SOUTHERN
COUNTIES. HIGHS WILL RANGE IN THE UPPER 70S TO LOWER 80S WITH
MUGGY DEW POINTS IN THE 60S.
FOR TONIGHT THROUGH TUESDAY...A SURGE OF DEEP TROPICAL MOISTURE
WILL PUSH INTO TN. PRECIPITABLE WATER VALUES WILL REACH AROUND 2
INCHES BY TUESDAY MORNING. AT THE SAME TIME...IMPULSES WILL LIFT
NORTHWARD AHEAD OF THE TX UPPER LEVEL LOW...AND A DISTURBANCE WILL
APPROACH FROM THE NORTHWEST. THE TROPICAL LOW WILL TRACK ACROSS
NORTH FL TOWARD THE CAROLINA COAST...BUT MOISTURE WITH THIS SYSTEM
WILL SPREAD WELL NWWD TO THE TN VALLEY. THESE INGREDIENTS WILL
LEAD TO WIDESPREAD SHOWERS AND A FEW THUNDERSTORMS LATE TONIGHT
THROUGH TUESDAY. AVERAGE RAINFALL AMOUNTS THROUGH TUESDAY ARE
EXPECTED TO RANGE FROM AROUND ONE HALF INCH OVER OUR NORTHWEST
COUNTIES TO MORE THAN 1 INCH OVER THE SOUTH. LOCALLY GREATER
AMOUNTS WITH HEAVY DOWNPOURS ARE LIKELY OVER THE SOUTH AND
PLATEAU AS WELL.
UPPER LEVEL WINDS WILL TURN NORTHWEST TUESDAY NIGHT INTO WEDNESDAY
WITH A COLD FRONT PASSAGE. THE COVERAGE AND INTENSITY OF SHOWERS
WILL DECREASE.
.LONG TERM...COOLER AIR WILL MOVE IN FOR THE EXTENDED FORECAST.
OVERNIGHT LOWS WILL BE DIPPING INTO THE 50S WITH HIGHS MAINLY IN
THE UPPER 60S TO LOWER 70S...WHICH WOULD BE JUST A COUPLE OF
DEGREES COOLER THAN NORMAL. MODELS SUGGEST AN UPPER TROUGH WILL
LINGER...POSSIBLY KEEPING SOME SHOWERS AROUND FOR THE UPPER
CUMBERLAND REGION LATE WEEK THROUGH THE WEEKEND. ANOTHER SYSTEM
MAY BRING SCATTERED SHOWERS ACROSS THE AREA INTO EARLY NEXT
WEEK...BUT CONFIDENCE IS LOW REGARDING THE DETAILS.
13
&&
.PREV DISCUSSION... /ISSUED 1142 PM CDT SUN SEP 27 2015/
AVIATION UPDATE...
RAIN ACTIVITY HAS BEEN UNDERWHELMING THIS EVENING AND HRRR DOES
NOT PAINT A WET PICTURE FOR THE REST OF THE OVERNIGHT HOURS. TOOK
OUT VCSH AT ALL THREE TERMINALS UNTIL MORNING WHERE GUIDANCE BUMPS
POPS SLIGHTLY. BR WILL BE AN ISSUE AT CKV AND CSV OVERNIGHT. THE
MORE SIGNIFICANT OMEGA AND RAIN CHANCES WILL HOLD OFF UNTIL AFTER
THE END OF THE TAF PERIOD. WINDS WILL BE E/SE UNDER 5 KTS DURING
THE TAF PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 81 66 78 65 / 40 80 90 50
CLARKSVILLE 81 66 78 63 / 30 60 80 40
CROSSVILLE 77 64 74 63 / 30 80 100 60
COLUMBIA 80 65 79 65 / 40 80 90 50
LAWRENCEBURG 79 65 79 65 / 50 80 90 50
WAVERLY 81 65 79 64 / 30 70 80 40
&&
.OHX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1142 PM CDT SUN SEP 27 2015
.AVIATION UPDATE...
RAIN ACTIVITY HAS BEEN UNDERWHELMING THIS EVENING AND HRRR DOES
NOT PAINT A WET PICTURE FOR THE REST OF THE OVERNIGHT HOURS. TOOK
OUT VCSH AT ALL THREE TERMINALS UNTIL MORNING WHERE GUIDANCE BUMPS
POPS SLIGHTLY. BR WILL BE AN ISSUE AT CKV AND CSV OVERNIGHT. THE
MORE SIGNIFICANT OMEGA AND RAIN CHANCES WILL HOLD OFF UNTIL AFTER
THE END OF THE TAF PERIOD. WINDS WILL BE E/SE UNDER 5 KTS DURING
THE TAF PERIOD.
&&
.PREV DISCUSSION... /ISSUED 842 PM CDT SUN SEP 27 2015/
UPDATE...
WEAK ISENTROPIC UPGLIDE WILL KEEP CLOUDS AND LIGHT SHOWER CHANCES
GOING THROUGH THE OVERNIGHT AND DURING THE DAY MONDAY. CURRENTLY
SPOTTY LIGHT SHOWERS ARE CONTINUING TO WORK NORTHWARD FROM ALABAMA
INTO MIDDLE TENNESSEE. LOOKS LIKE CLOUDS WILL ALSO CONTINUE TO
THICKEN UP AS WE GO THROUGH THE EVENING AND OVERNIGHT...THEREFORE
IT DOESNT LOOK GOOD FOR ECLIPSE VIEWING. TEMPS SHOULD BE IN THE
LOW TO MIDDLE 60S FOR OVERNIGHT MINS.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 66 81 67 81 / 30 30 30 60
CLARKSVILLE 64 81 65 81 / 20 20 30 60
CROSSVILLE 63 76 64 74 / 30 30 60 70
COLUMBIA 65 80 65 79 / 40 30 40 60
LAWRENCEBURG 65 79 66 78 / 40 40 40 60
WAVERLY 65 81 65 80 / 20 20 30 60
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
10
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
157 AM EDT MON SEP 28 2015
.SYNOPSIS...
A COMPLEX AREA OF LOW PRESSURE ACROSS THE REGION WILL MAINTAIN A
STRONG ONSHORE FLOW OF MOISTURE INTO THE AREA OVERNIGHT. THIS
WILL COMBINE WITH A STRONG WEDGE OF HIGH PRESSURE ALONG THE
APPALACHIANS AND LEAD TO CONTINUED WIDESPREAD RAIN OR DRIZZLE
UNDER GUSTY NORTHEAST WINDS AND COOL TEMPERATURES. WEAK HIGH
PRESSURE WILL BUILD INTO THE AREA ON MONDAY...BEFORE LOW PRESSURE
APPROACHES FROM THE GULF COAST REGION BY MIDWEEK...POSSIBLY
BRINGING ANOTHER ROUND OF HEAVIER RAINFALL BY TUESDAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 951 PM EDT SUNDAY...
HIGH PRESSURE REMAINS WEDGED AGAINST THE EASTERN SLOPES OF THE
APPALACHIANS TONIGHT...MAINTAINING A COOL NORTHEAST WIND. AT THE
SAME TIME...LOW PRESSURE OFF THE COAST CONTINUES TO PUSH DEEP
MOISTURE INTO THE HIGHER TERRAIN. PERIODS OF RAIN...DRIZZLE AND
FOG WILL CONTINUE OVERNIGHT INTO MONDAY MORNING. HEAVIER BANDS OF
RAIN ARE DEVELOPING AND LIFT NORTH. RAINFALL OVERNIGHT WILL BE
ENHANCE ALONG THE BLUE RIDGE WITH THE HEAVIEST AMOUNTS EXPECTED
ALONG THE SOUTHERN BLUE RIDGE. ADJUSTED TEMPERATURES THIS EVENING
INTO TONIGHT WITH THE LATEST OBS AND MODEL TRENDS. TEMPERATURES
RUNNING COOLER IN SEVERAL AREAS THIS EVENING WITH RAIN AND CLOUDS.
SHAPED THE NEXT COUPLE OF HOURS FOR POPS TOWARDS HIRESW-ARW-
EAST...RUC AND HRRR WITH THE AXIS ON THE WEST. INCREASED QPF FOR
TONIGHT ALONG SOUTHERN BLUE RIDGE AND WESTERN MOUNTAINS. WITH
SATURATED GROUNDS...WE WILL HAVE TO WATCH FOR LOCALIZED FLOODING
ISSUES OVERNIGHT INTO MONDAY MORNING.
AS OF 650 PM EDT SUNDAY...
MADE SOME MINOR ADJUSTMENTS IN TEMPERATURES AND DEW POINTS FOR
THIS EVENING INTO TONIGHT.
AS OF 330 PM EDT SUNDAY...
FOR THIS EVENING AND TONIGHT...EXPECT LITTLE CHANGE FROM CURRENT
CONDITIONS AS HIGH PRESSURE REMAINS WEDGED AGAINST THE EASTERN
FACE OF THE APPALACHIANS...MAINTAINING A COOL NORTHEAST WINDFLOW
ACROSS THE MID ATLANTIC. AT THE SAME TIME...LOW PRESSURE OFF THE
COAST CONTINUES TO PUSH DEEP MOISTURE INTO THE HIGHER TERRAIN...
RESULTING IN WIDESPREAD LOW CLOUDS AND SCATTERED BANDS OF RAIN.
RAIN WILL CONTINUE AREAWIDE...REMAINING HEAVIEST/MOST PERSISTENT
IN THE VICINITY OF THE BLUE RIDGE WHERE THE UPSLOPE CONDITIONS
WILL AMPLIFY RAINFALL INTENSITY. AS SUCH...MAY SEE AN ADDITIONAL
ONE TO TWO INCHES OF RAINFALL NEAR THE BLUE RIDGE PARKWAY THROUGH
MONDAY MORNING. THE DEEP MOISTURE AND LOW CLOUDS WILL NOT ALLOW
FOR MUCH COOLING OVERNIGHT HOWEVER...WITH OVERNIGHT LOWS EXPECTED
TO RANGE FROM THE UPPER 50S TO THE LOW 60S.
RAINFALL WILL BE MORE SPOTTY ON MONDAY AS HIGH PRESSURE WEDGING
WEAKENS...AND ONSHORE FLOW OF MOISTURE DIMINISHES...MAKING
MOISTURE MORE SHALLOW ACROSS OUR AREA. THAT STATED...EXPECT WE
WILL STILL SEE SPOTTY BANDS OF RAIN MAKE THEIR WAY ACROSS THE
AREA FROM THE COAST. WITH THE CONTINUED UPSLOPE FLOW...PERSISTENT
AND OCCASIONALLY HEAVY RAINFALL CAN AGAIN BE EXPECTED ALONG THE
BLUE RIDGE AND OTHER EAST FACING SLOPES. NEEDLESS TO SAY...DO NOT
EXPECT WE WILL SEE CLOUDS BREAK OUT ANYWHERE OUTSIDE OF WESTERN
TAZEWELL COUNTY...WHERE A FEW RAYS OF SUNSHINE MAY BE POSSIBLE
DURING THE AFTERNOON. REGARDLESS...WITH LESS RAINFALL EXPECTED...
BELIEVE AFTERNOON TEMPERATURES WILL BE WARMER...ALTHOUGH BELOW
THE COOLER MAV GUIDANCE. MONDAY AFTERNOON HIGHS WILL RANGE FROM
THE LOW/MID 60S ALONG THE RIDGES...TO THE LOW 70S ACROSS THE
PIEDMONT.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
AS OF 330 PM EDT SUNDAY...
OVERALL PATTERN DOES NOT CHANGE APPRECIABLY IN THE EARLY TO MID-WEEK
PATTERN WITH UPPER LEVEL TROUGH TO THE WEST MAINTAINING VERY MOIST
SOUTHERLY FLOW ALOFT INTO THE SOUTHERN APPALACHIANS AND MID-ATLANTIC
REGION. HIGH PRESSURE OVER SOUTHEAST CANADA WILL ALSO KEEP SOME
SEMBLANCE OF A WEDGE ACROSS THE AREA WITH EAST TO NORTHEAST FLOW IN
THE LOWER LEVELS. SUN SEEKERS SHOULD DEFINITELY LOOK ELSEWHERE AS
OVERCAST SKIES AND CHANCES FOR RAINFALL ARE VERY LIKELY TO PERSIST
RIGHT INTO MID-WEEK AND BEYOND. A SLOW-MOVING COLD FRONT OVER THE
MIDWEST AT THE OUTSET OF THE PERIOD WILL PUSH SLOWLY SOUTHEAST AND
ACROSS THE FORECAST AREA TUESDAY...WITH INCREASING CHANCES FOR
ORGANIZED RAINFALL AHEAD OF AND ALONG THE FRONT TUESDAY INTO
WEDNESDAY. MODEL QPFS PER EURO/GFS RANGE FROM 1 TO 3+ INCHES FROM
LATE MONDAY INTO LATE WEDNESDAY WHICH SUGGESTS A POSSIBILITY FOR
RIVER FLOODING (SEE HYDRO SECTION BELOW) ACROSS BASINS WHICH HAVE
BECOME MUCH MORE SATURATED WITH THIS WEEKENDS RAINFALL. TEMPS WILL
HAVE NARROW DIURNAL RANGES DURING THE PERIOD WITH THE EXTENSIVE
CLOUD COVER MAINLY FROM UPPER 50S/LOW 60S AT NIGHT TO UPPER 60S/LOW
70S IN THE DAY.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 330 PM EDT SUNDAY...
THE COLD FRONT SHOULD STALL OFF THE EAST COAST BY EARLY THURSDAY
WITH ONE OR MORE WAVES OF LOW PRESSURE POSSIBLY DEVELOPING ALONG THIS
BOUNDARY. TOO EARLY TO TELL EXACT POSITIONING AND EFFECTS OF ANY
SUCH DEVELOPMENT...BUT 12Z GFS IS ACTUALLY QUITE WET ACROSS EVEN
CENTRAL AND WESTERN CWA ON FRIDAY INTO EARLY SATURDAY SO AT LEAST
CHANCE POPS ARE HELD IN THE GRIDS THROUGH SATURDAY ALTHOUGH STILL
HAVE HIGHEST CHANCES IN THE EAST AND TRENDING TOWARD ONLY SLIGHT
CHANCE IN THE FAR WEST. TEMPS SHOULD BE SLIGHTLY COOLER BEHIND THE
FRONT WITH LOW 60S NW TO UPPER 60S SE FOR HIGHS AND MID 40S TO LOW
50S FOR LOWS.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 155 AM EDT MONDAY...
POOR FLYING CONDITIONS EXPECTED TODAY AND TONIGHT. DEEP SOUTHEAST
WINDS AROUND A HIGH CENTERED OFF OF THE NEW ENGLAND COAST WILL
RESULT IN WIDESPREAD LIFR TO MVFR CEILINGS TODAY AND TONIGHT.
AREAS OF DRIZZLE...FOG AND LIGHT RAIN ARE EXPECTED THROUGH MID
MORNING WITH VISIBILITIES MAINLY IN THE MVFR RANGE.
BUFKIT AND MODEL FORECASTS SHOWED A 30 TO 35 KNOT SOUTHEAST LOW
LEVEL JET AT THE 06Z/2AM START OF THE TAF PERIOD OVER SOUTHEAST
WEST VIRGINIA. HIGH CONFIDENCE OF OCCASIONAL WIND GUSTS OF 20 TO
25 KNOTS AT KBLF UNTIL 12Z WHEN THE JET BECOMES WEAKER.
AFTER SUNRISE CEILINGS WILL GRADUALLY IMPROVE A FEW HUNDRED
FEET AND AS THE SOUTHEAST UPSLOPE WINDS WEAKEN...FOG AND DRIZZLE
WILL BECOME MORE PATCHY AND LESS WIDESPREAD. MODERATE CONFIDENCE
AS TO HOW MUCH CEILINGS WILL RISE TODAY...ESPECIALLY AT KLYH/KROA
AND KBCB. CEILINGS WILL LOWER AGAIN AFTER SUNSET BACK TO IFR AND
LIFR VALUES.
EXTENDED AVIATION DISCUSSION...
ANOTHER STORM SYSTEM WILL APPROACH LATE TUESDAY...BRINGING
ANOTHER ROUND OF POTENTIALLY HEAVY RAIN...AS WELL AS SUB VFR
CEILINGS/VISIBILITIES INTO WEDNESDAY. A DEVELOPING WEDGE MAY KEEP
MVFR CEILINGS IN PLACE FOR LATE IN THE WEEK.
&&
.HYDROLOGY...
AS OF 345 PM EDT SUNDAY...
SMALLER STREAMS AND CREEKS HAVE CRESTED FOR THE MOST PART WITH
NOTHING HAVING REACHED EVEN ACTION STAGE DESPITE WIDESPREAD 1 TO 4
INCHES IN 72 HOURS AND UP TO 8 OR MORE INCHES OF IN ISOLATED PARTS
OF THE BLUE RIDGE. THE HEAVIEST RAIN FELL IN THE UPPER REACHES OF
THE DAN AND SMITH RIVER BASINS AND WHATEVER RUNOFF OCCURRED WILL BE
MAKING ITS WAY DOWNSTREAM. PHILPOTT RESERVOIR CAUGHT A SUBSTANTIAL
PORTION OF THE SMITH RIVER BASIN RUNOFF WITH THE RESERVOIR ELEVATION
CLIMBING OVER 2 FEET OVER THE PAST TWO DAYS. FURTHER DOWNSTREAM THE
DAN IS STILL RISING ALONG ITS ENTIRE REACH BUT IS STILL CURRENTLY
FORECAST TO CREST BELOW ACTION STAGE EVEN AT FLOOD-PRONE SOUTH
BOSTON. WITH MORE RAIN ON THE WAY SOME OF IT POSSIBLY HEAVY...
ESPECIALLY TUESDAY INTO WEDNESDAY AND POSSIBLY AGAIN LATER IN THE
WEEK IT WOULD BE PRUDENT TO PAY CLOSE ATTENTION TO RIVER FORECASTS
AS THEY WILL LIKELY BE UPDATED FREQUENTLY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...NF
NEAR TERM...KK/NF
SHORT TERM...PC
LONG TERM...AMS/PC
AVIATION...AMS
HYDROLOGY...JH/MBS
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
915 PM CDT TUE SEP 29 2015
.UPDATE...
FORECAST APPEARS TO BE ON TRACK WITH ONLY A FEW MINOR TWEAKS TO
SKY AND TEMPS TO ACCOUNT FOR LAKE CLOUD POTENTIAL LATER TONIGHT.
&&
.AVIATION/06Z TAFS/...
EXPECT VFR CONDITIONS THROUGH THE FORECAST...THOUGH WILL BE
WATCHING POTENTIAL LAKE CLOUD DEVELOPMENT/HEIGHTS/AMOUNTS
OVERNIGHT INTO WEDNESDAY MORNING. RAP SOUNDINGS HAVE BEEN FIXED
ON MVFR LEVEL CLOUD DEVELOPMENT AROUND 2500 FT...BUT RIGHT NOW
ONLY SCATTERED COVERAGE.
&&
.MARINE...
PERSISTENT NORTHEAST WINDS GUSTING TO 25 KNOTS WILL KEEP WAVES
HIGH THROUGH THE DAY WEDNESDAY AND WEDNESDAY NIGHT. WILL ALLOW
LATER SHIFT A FULL LOOK AT LATEST 00Z MODEL DATA...BUT
INDICATIONS ARE THAT CURRENT 12Z THURSDAY END TIME MAY HAVE TO BE
EXTENDED WITH LATEST NAM SHOWING 15 KNOT SUSTAINED SURFACE WINDS
OUT OF THE EAST-NORTHEAST AND 925 MB WINDS OF 20-25 KNOTS MIXING
TO THE SURFACE...WITH ENOUGH FETCH TO KEEP WAVES AT OR ABOVE
SMALL CRAFT CRITERIA INTO FRIDAY.
&&
.PREV DISCUSSION... /ISSUED /
TONIGHT AND WEDNESDAY...FORECAST CONFIDENCE...HIGH
HIGH PRESSURE WILL BUILD IN FROM THE NORTH TONIGHT INTO WEDNESDAY.
SKIES SHOULD BE MOSTLY CLEAR FOR AT LEAST THE EVENING HOURS. COULD
SEE SOME LAKE EFFECT CLOUDS DEVELOP TONIGHT...WITH LAKE SFC TO 850
MB DELTA T VALUES INCREASING TO 14Z BY DAYBREAK WEDNESDAY. NAM THEN
ADVECTS THIS AREA OF HIGHER MOISTURE TO THE WEST DURING THE
DAY...LIKELY RESULTING IN AT LEAST SCATTERED CUMULUS.
WILL BE A SIZABLE SPREAD IN LOW TEMPS TONIGHT...RANGING FROM THE
UPPER 30S NORTHWEST...TO THE LOW 50S SOUTHEAST WHERE ONSHORE WINDS
OFF THE WARMER LAKE WILL KEEP THINGS MILDER.
NORTHEAST WINDS WILL REMAIN ON THE BREEZY SIDE
WEDNESDAY...ESPECIALLY TOWARD LAKE MICHIGAN. SHOULD SEE A GOOD
AMOUNT OF SUNSHINE EVENTUALLY...DEPENDING ON THE EXTENT OF LAKE
CLOUDS. 925 MB TEMPS ONLY IN THE 8-9C RANGE TOMORROW...SO EXPECTING
HIGHS ONLY AROUND 60.
THURSDAY THROUGH SATURDAY...FORECAST CONFIDENCE IS HIGH.
HIGH PRESSURE WILL REMAIN STATIONARY FROM ONTARIO/QUEBEC CANADA
SOUTH THROUGH THE GREAT LAKES DURING THE PERIOD. THIS WILL PROVIDE
A PRETTY COOL AIRMASS SOURCE FOR THE EXPECTED NORTHEAST WINDS.
TEMPERATURES WILL BE QUITE COOL WITH HIGHS RUNNING IN THE UPPER
50S TO LOWER 60S AND LOWS IN THE LOWER/MID 40S. THE NORTHEAST
WIND FETCH AND MODERATE DELTA T OVER LAKE MICHIGAN SHOULD BRING
SOME LAKE CLOUDS DURING THE LATE NIGHT AND EARLY MORNING HOURS TO
THE EASTERN COUNTIES...BLOWING INLAND DURING THE DAY AS THEY
GRADUALLY WIPE OUT WITH WARMING DAYTIME TEMPS. THIS SCENARIO COULD
REPEAT EVERY NIGHT/MORNING.
SUNDAY...FORECAST CONFIDENCE LOW...
WE/VE INTRODUCED SOME SMALL CHANCES OF RAIN FOR SAT NIGHT INTO SUN
NIGHT DUE TO SFC LOW PRESSURE OVER THE SOUTHEAST U.S. MOVING
NORTH INTO THE EASTERN GREAT LAKES. A LARGE CLOSED LOW WILL LIFT
OUT OF THE SOUTHEAST U.S. AND HEAD SOMEWHERE UP THE EAST COAST.
SOMEWHERE IS THE KEY HERE AS THE 3 LONG RANGE MODELS USED HAVE
SOMEWHAT DIFFERENT SCENARIOS. THE GFS AND THE OLD ECMWF HAD THE
ASSOCIATED SURFACE LOW COMING CLOSE ENOUGH TO US TO BRING A CHANCE
OF RAIN OVER THE EAST. THE NEW ECMWF IS NOW KEEPING IT FARTHER
AWAY...KEEPING THE EAST DRY. WE/LL LET THIS PLAY OUT OVER THE NEXT
FEW DAYS...THUS CONFIDENCE IS LOW ON WHICH TRACK IS RIGHT. CLOSED
LOWS ARE OFTEN VERY DIFFICULT FOR THE MODELS TO HANDLE...ESPECIALLY
IN THE LONG RANGE.
MONDAY...CONFIDENCE IS LOW...
HIGH PRESSURE SHOULD RETURN AND BRING A DRY EARLY START TO NEXT
WEEK.
AVIATION/00Z TAFS/...
LINGERING MVFR CONDITIONS IN THE SOUTHEAST SHOULD IMPROVE TO VFR BY
MID AFTERNOON AS CLOUDS CONTINUE TO DECREASE FROM THE NORTHWEST.
WILL HAVE TO WATCH POSSIBLE LAKE EFFECT CLOUDS DEVELOPING
TONIGHT...WHICH SOUNDINGS SHOW MAY BE MVFR FOR A TIME. NAM SHOWS
THIS AREA OF HIGHER MOISTURE AND CLOUDS ADVECTING WEST DURING THE
DAY WEDNESDAY...WITH DAYTIME MIXING LIFTING THE CLOUDS BASES TO VFR
BY MID MORNING.
OTHERWISE...QUIET WEATHER IS EXPECTED TONIGHT AND WEDNESDAY AS HIGH
PRESSURE BUILDS INTO THE AREA.
MARINE...
HAVE DECIDED TO EXTEND THE SMALL CRAFT ADVISORY FOR ALL MARINE ZONES
INTO WEDNESDAY NIGHT. PERSISTENT NORTHEAST WINDS WILL GUST TO 25
KNOTS AT TIMES AND WILL KEEP WAVES ON THE HIGHER END.
MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 1 AM CDT THURSDAY FOR LMZ643>646.
$$
TONIGHT/WEDNESDAY AND AVIATION/MARINE...DDV
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 AM CDT THURSDAY FOR LMZ643>646.
&&
$$
UPDATE...REM
TONIGHT/WEDNESDAY AND AVIATION/MARINE...DDV
WEDNESDAY NIGHT THROUGH TUESDAY...DAVIS
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
650 PM MDT TUE SEP 29 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 350 PM MDT TUE SEP 29 2015
ISOLATED SHOWERS AND WEAK THUNDERSTORMS WILL TRY TO SHIFT INTO THE
PLAINS THIS EVENING. LOW LEVEL CAP WILL KEEP THUNDERSTORMS FROM
MAKING IT VERY FAR EAST. MOST THUNDERSTORM ACTIVITY OR AT LEAST
ANY STRONGER THUNDERSTORMS SHOULD DIE OFF AROUND INTERSTATE 25.
THERE IS THE POTENTIAL FOR SOME SHOWERS AND THUNDERSTORMS TO
BECOME ELEVATED AS THE LEFT EXIT REGION OF AN UPPER LEVEL JET
SLIDES INTO THE AREA THIS EVENING. HRRR MODEL...WHICH HAS HANDLED
SHOWER AND THUNDERSTORM ACTIVITY FAIRLY WELL THE LAST COUPLE DAYS
DOES DEVELOP ELEVATED CONVECTION. BASED ON THE HRRR THE ACTIVITY
OVER THE SOUTHERN LARAMIE RANGE WILL DIE OFF AS IT MOVES INTO
SOUTHEAST WYOMING/NORTHEAST COLORADO WHILE ANOTHER BATCH OF
ACTIVITY WILL FORM OVER THE NORTHERN LARAMIE RANGE LATE THIS
AFTERNOON AND THEN MOVE SOUTHEAST INTO THE SOUTHERN NEBRASKA
PANHANDLE BY MID EVENING. FORECAST POPS GENERALLY REPRESENT THE
HRRR SOLUTION THROUGH THIS EVENING. SEVERE THUNDERSTORM ARE VERY
UNLIKELY BUT A FEW WINDS GUSTS UPWARDS OF 50 MPH AND PEA SIZED
HAIL CAN NOT BE RULED OUT WITH A FEW STRONGER THUNDERSTORMS.
LOW STRATUS AND PATCHY FOG WILL REDEVELOP OVER MUCH OF THE PLAINS
THIS EVENING. NOT CONFIDENT IN HOW FAR WEST AND NORTH THE STRATUS
AND FOG WILL MAKE IT BUT IT COULD PARALLEL THE LARAMIE RANGE FOR A
WHILE TONIGHT. WINDS SHOULD BECOME WEST ALONG THE LARAMIE RANGE
AFTER MIDNIGHT WHICH WILL BEGIN TO ERODE THE WESTERN FLANKS OF
FOG AND STRATUS. COULD ALSO SEE SOME DRIZZLE TONIGHT INTO THE
NEBRASKA PANHANDLE AS THERE WILL BE AN AREA OF WEAK THETAE
ADVECTION NEAR THE TOP OF A SHALLOW SATURATED INVERSION. MOST OF
THE FOG/LOW STRATUS/DRIZZLE WILL ERODE EASTWARD INTO THE PLAINS
THROUGH THE DAYLIGHT HOURS TOMORROW BUT PLACES LIKE ALLIANCE AND
SIDNEY NEBRASKA MAY NOT SEE THE SUN TOMORROW AS A LOW LEVEL
INVERSION MAY HOLD THE STRATUS IN PLACE.
CHANCES FOR THUNDERSTORMS WILL BE MINIMAL WEDNESDAY WITH THE MAIN
CHANCES IN AND NEAR THE SNOWY RANGE AND SIERRA MADRE RANGE. THE
MODELS ARE SHOWING SURFACE BASED CAPES OF 500-1000 J/KG INTO THE
PLAINS WEDNESDAY AFTERNOON. THE MAIN QUESTION IS WHETHER OR NOT
THE CAP WILL HOLD AND IF THERE WILL BE ANY UPPER LEVEL SUPPORT IN
PLACE. NOT CONFIDENT THERE WILL BE STORMS INTO THE PLAINS BUT IT
WILL BE SOMETHING TO WATCH.
MORE FOG AND LOW STRATUS LIKELY FOR THE PLAINS WEDNESDAY NIGHT
INTO THURSDAY MORNING. SMALL CHANCES FOR SHOWERS AND
THUNDERSTORMS AGAIN THURSDAY AFTERNOON.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 300 PM MDT TUE SEP 29 2015
RAIN AND SHOWERS SHOULD SPREAD ACROSS THE CWA DURING THE DAY
FRIDAY AS THE WESTERN CONUS UPPER TROF MOVES EAST AND PIVOTS
ACROSS THE CWA THROUGH FRIDAY NIGHT. SOME SNOW STILL POSSIBLE OVER
THE HIGHER MTNS BUT NOT A LOT OF COLD AIR WITH THIS SYSTEM SO ANY
ACCUMULATIONS INTO SAT MORNING SHOULD BE ON THE LOW SIDE. SOME
LULL IN THE PCPN ON SATURDAY BEFORE NEXT IMPULSE IN THE FLOW
ROTATES ACROSS SAT NIGHT BRINGING ANOTHER ROUND OF PCPN. IN THE
MEANTIME A POTENT UPPER LOW WILL DROP DOWN ALONG THE WEST COAST
SAT NIGHT AND SUNDAY BEFORE BEGINNING A SLOW DRIFT NORTHEAST EARLY
NEXT WEEK. SHORT RIDGING WILL BUILD OVER THE CWA SUNDAY DRYING
THINGS OUT AND ALLOWING FOR MILDER TEMPS AFTER A COOL DAY
SATURDAY. THIS SHOULD CONTINUE THROUGH MOST OF MONDAY BEFORE THE
UPPER LOW BEGINS SPREADING PCPN BACK OVER THE CWA MONDAY NIGHT
INTO TUESDAY. AGAIN SNOWS LOOK TO BE CONFINED TO THE HIGHER MTN
ELEVATIONS. TEMPERATURES REMAINING MILD...CLOSE TO SEASONAL
AVERAGES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 645 PM MDT TUE SEP 29 2015
SHOWERS AND THUNDERSTORM OVER FAR SOUTHEAST WYOMING AND SOUTHERN
NEBRASKA PANHANDLE WILL CONTINUE TO WEAKEN WHILE MOVING SOUTHEAST
ACROSS THE AREA. MOST ALL SHOWER AND THUNDERSTORM ACTIVITY SHOULD
END BY 06Z TONIGHT. LOW STRATUS WITH PATCHY FOG AND DRIZZLE WILL
BE FOUND ACROSS THE NEBRASKA PANHANDLE LATER TONIGHT. STRATUS AND
FOG MAY REACH AS FAR WEST AS THE LARAMIE RANGE FOR A WHILE
TONIGHT. IT MAY TAKE A WHILE FOR THE FOG AND STRATUS TO ERODE
WEDNESDAY WITH IFR CONDITIONS POSSIBLY HOLDING ON INTO MID
AFTERNOON FOR PLACES LIKE KSNY AND KAIA.
&&
.FIRE WEATHER...
ISSUED AT 350 PM MDT TUE SEP 29 2015
HUMIDITY VALUES WILL DIP INTO THE 20 TO 25 PERCENT RANGE OVER SOUTH
CENTRAL WYOMING WEDNESDAY AND THURSDAY AFTERNOON WITH WIND GUSTS
BETWEEN 20 TO 25 MPH. THAT WILL BE THE ONLY AREA WITH ANY FIRE
WEATHER CONCERNS THIS WEEK. OTHERWISE RELATIVE HUMIDITY VALUES
WILL REMAIN ON THE HIGH SIDE OVER THE PLAINS THIS WEEK. AN UPPER
LEVEL LOW IS STILL EXPECTED TO IMPACT THE REGION LATE FRIDAY THROUGH
SATURDAY. WIDESPREAD WETTING RAIN IS LIKELY ALONG WITH SNOW INTO THE
MOUNTAINS OF SOUTHEAST WYOMING. MOST SNOW ACCUMULATIONS WILL BE ABOVE
9000 FEET BUT COULD SEE SOME SNOW AS LOW AS 8000 FEET.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...SML
LONG TERM...RE
AVIATION...SML
FIRE WEATHER...SML
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
333 AM MDT MON SEP 28 2015
.SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT)
ISSUED AT 325 AM MDT MON SEP 28 2015
CURRENT SURFACE OBS ACROSS THE AREA SHOW A WEAK COLD FRONT NEAR
THE NORTH PLATTE RIVER VALLEY EXTENDING FROM NEAR DOUGLAS WYOMING
SOUTHEAST INTO THE SOUTHERN NEBRASKA PANHANDLE. WINDS HAVE STARTED
TO SHIFT INTO THE NORTHEAST ACROSS NIOBRARA COUNTY AND MOST OF THE
NORTHERN NEBRASKA PANHANDLE. THE FRONT WILL STALL NEAR THE
MOUNTAINS THIS AFTERNOON AND REMAIN NEARLY STATIONARY JUST WEST OF
THE LARAMIE RANGE INTO TUESDAY. THE JET STREAM WILL BECOME MORE
ACTIVE TODAY AS WELL...AS A 90 KNOT JET STREAK IS FORECAST TO
PUSH ACROSS WYOMING TODAY. THE COMBINATION OF THE FRONT AND A MORE
ACTIVE JET WILL SET THE STAGE FOR A BETTER CHANCE OF SHOWERS AND
TSTORMS TODAY AND TUESDAY AS SOME LLVL INSTABILITY WILL BE
PRESENT. EXPECT BANDS OF SHOWERS WITH EMBEDDED TSTORMS TO DEVELOP
ACROSS THE MOUNTAINS OF CENTRAL WYOMING AND QUICKLY MOVE EASTWARD
INTO THE HIGH PLAINS TODAY AND INTO TONIGHT...ESPECIALLY BETWEEN
3 PM AND MIDNIGHT TONIGHT WHEN MODELS INDICATE THE BEST LIFT
ASSOCIATED WITH THE JET STREAK WILL BE OVER THE FORECAST AREA.
WITH GOOD UPSLOPE FLOW AND A DECENT CHANCE OF RAINFALL...LOW
STRATUS AND PATCHY FOG IS POSSIBLE LATE TONIGHT AND EARLY TUESDAY
ALONG AND EAST OF THE LARAMIE RANGE. HIGH TEMPERATURES TODAY WILL
BE 15 TO 20 DEGREES COOLER COMPARED TO SATURDAY/SUNDAY WITH HIGHS
IN THE MID 60S TO MID 70S EXPECTED.
TUESDAYS FORECAST WILL BE TRICKY SINCE MODELS INDICATE LOW STRATUS
CLOUDS HANGING ON EAST OF THE LARAMIE RANGE THROUGH THE DAY. THIS
MAY RESULT IN HIGH TEMPERATURES STRUGGLING TO REACH 60 DEGREES
OVER MOST OF WESTERN NEBRASKA AND PORTIONS OF SOUTHEAST WYOMING
TUESDAY AFTERNOON. JUST TO THE WEST...WINDS WILL GRADUALLY SHIFT
INTO THE WEST ALLOWING SOME DRY AIR TO PUSH INTO THE AREA.
HOWEVER...SUNSHINE WILL INCREASE LLVL INSTABILITY AND ALLOW
SHOWERS AND TSTORMS TO REDEVELOP. KEPT POP BETWEEN 25 TO 40
PERCENT ACROSS THE MOUNTAINS FOR SHOWERS AND A FEW TSTORMS. MODEL
SOUNDINGS DO SHOW AMPLE INSTABILITY ACROSS SOUTHEAST WYOMING WITH
CAPE VALUES AROUND 1000 J/KG IN ADDITION TO MODERATE LOW TO
MIDLEVEL SHEAR. WILL NEED TO WATCH AREAS ALONG AND WEST OF I25 FOR
STRONG TSTORMS.
FOR WEDNESDAY...MODELS ALL SHOW AN UPPER LEVEL RIDGE AXIS
AMPLIFYING ALONG THE CONTINENTAL DIVIDE. LITTLE TO NO CHANCE OF
CONVECTION DUE TO MIDLEVEL SUBSIDENCE AND DRIER AIR. HIGH
TEMPERATURES WILL REBOUND INTO THE MID 70S TO LOW 80S ACROSS THE
AREA...WARMEST JUST EAST OF THE LARAMIE RANGE.
.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 236 AM MDT MON SEP 28 2015
MODELS HAVE COME INTO PRETTY GOOD AGREEMENT WITH REGARD TO THE STORM
SYSTEM THAT WILL IMPACT THE REGION BY FRI/SAT. MIDLVL RIDGE AXIS
WILL BE OVERHEAD ON THURS AND IT WILL LIKELY BE THE WARMEST DAY WITH
HIGHS MOSTLY IN THE 70S. UPPER TROUGH WILL MOVE EASTWARD FROM THE
GREAT BASIN ON THURS AND BE LOCATED NEAR WYOMING BY FRI. LLVL
MOISTURE ADVECTION WILL OCCUR ON THURS NIGHT WITH SOUTHEASTERLY
UPSLOPE WINDS ACROSS THE PLAINS. BOTH THE GFS AND ECMWF SHOW THE
BEST UPPER LEVEL DIVERGENCE/LARGE SCALE ASCENT DURING THE DAY ON
FRI. WITH CLOUDY SKIES AND RAINFALL OCCURRING...DROPPED HIGHS A FEW
DEGREES ON FRI. SNOW COULD BE POSSIBLE IN THE HIGHEST MTNS ON FRI
(ABOVE AROUND 11000 FT).
THE GFS AND ECMWF BEGIN TO DIVERGE BY SAT. THE GFS WEAKENS THE
UPPER TROUGH BUT DROPS IT SOUTHEAST INTO COLORADO. THIS KEEPS LIGHT
PRECIP MAINLY FROM LLVL UPSLOPE GOING THROUGH THE DAY ALONG WITH
COLD AIR ADVECTION (700MB TEMPS DROP TO -2C). THE ECMWF ON THE
OTHER HAND IS PROGRESSIVE WITH THE TROUGH SWINGING INTO NEBRASKA.
REGARDLESS OF THE SOLN IT WILL BE A RATHER COOL DAY WITH HIGHS
STRUGGLING TO GET OUT OF THE MID 50S (EVEN COLDER ON THE GFS).
HEIGHTS ALOFT RISE BY SUNDAY BUT IT WILL STILL BE COOL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1037 PM MDT SUN SEP 27 2015
VFR CONDITIONS FOR ALL SOUTHEAST WYOMING AND NEBRASKA PANHANDLE
AIRPORTS TONIGHT INTO MONDAY MORNING. HRRR GUIDANCE BEGINNING TO
INDICATE SOME FOG/IFR IN THE PLATTE RIVER VALLEY NEAR KBFF TOWARDS
12Z. NOT A FAVORABLE WIND DIRECTION THOUGH...SO DID NOT INCLUDE IN
THE 06Z TAF FOR KBFF. WILL SEE A CHANGE THOUGH MONDAY AFTERNOON
AS WE SEE NORTHEASTERLY UPSLOPING WINDS EAST OF THE LARAMIE RANGE.
CONTINUED THE TREND DOWN ON CEILINGS MONDAY AFTERNOON. WILL
LIKELY SEE IFR/LIFR CONDITIONS MONDAY EVENING FOR MUCH OF THE
PANHANDLE AND AIRPORTS EAST OF THE LARAMIE RANGE THROUGH TUESDAY.
&&
.FIRE WEATHER...
ISSUED AT 236 AM MDT MON SEP 28 2015
FIRE WEATHER CONCERNS WILL BE LOW THROUGH THIS WEEK DUE TO
RELATIVELY LIGHT WINDS AND DAYTIME HUMIDITIES ABOVE 20 PERCENT IN
MOST LOCATIONS. WEDNESDAY WILL BE THE DRIEST DAY WITH DAYTIME
RELATIVE HUMIDITIES POTENTIALLY LOWERING TO 15 PERCENT ACROSS
SOUTHEAST WYOMING BEFORE A STRONG COLD FRONT MOVES ACROSS THE AREA
LATE IN THE WEEK. WIDESPREAD WETTING RAINFALL AND MOUNTAIN SNOWS
ARE POSSIBLE FRIDAY AND SATURDAY AS A PACIFIC STORM SYSTEM MOVES
ACROSS THE AREA.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...TJT
LONG TERM...ZF
AVIATION...GCC
FIRE WEATHER...TJT
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1039 PM MDT SUN SEP 27 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 152 PM MDT SUN SEP 27 2015
LATEST SATELLITE IMAGERY SHOWS CLOUDS DEVELOPING THROUGH MOST OF
SOUTHEASTERN WYOMING WITH THE SFC TROUGH MOVING CONTINUING TO MOVE
TO THE EAST OUT OF THE CWA. CURRENTLY RADAR IS SHOWING
SHOWERS/TSTORM STAYING WELL NORTH OF THE CWA...BUT POPS ARE
POSSIBLE INTO THIS EVENING ESPECIALLY EAST OF THE LARAMIE RANGE
AND INTO CONVERSE AND NIOBRARA COUNTIES. CLOUDS WILL LINGER INTO
TONIGHT KEEPING TEMPERATURES SLIGHTLY WARMER.
TOMORROW AN UPPER LEVEL JET OVER SOUTHERN WYOMING WILL PROVIDE
SOME UPWARD MOTION INTO THE AFTERNOON AND EVENING HOURS. COMBINED
WITH UPSLOPE FLOW FROM EASTERLY WINDS NEAR THE SURFACE COULD
PRODUCE ISOLATED THUNDERSTORMS. GFS AND ECMWF SHOW AN INCREASE IN
QPF OVER THE SIERRA MADRES AND SNOWY RANGES EARLY IN THE DAY AND
THEN MOVING EASTWARD INTO THE NEBRASKA PANHANDLE. HIGHS TOMORROW
WILL BE SLIGHTLY COOLER WITH CLOUDS KEEPING TEMPERATURES DOWN FOR
MOST OF SOUTHEASTERN WYOMING AND THE NEBRASKA PANHANDLE.
ALTHOUGH...WEST OF THE LARAMIE RANGE TEMPERATURES ARE EXPECTED TO
BE WARMER WITH CLEARER SKIES. SOME STRATUS CLOUDS COULD DEVELOP
MONDAY NIGHT OVER THE NEBRASKA PANHANDLE MOVING DOWN FROM THE
NORTH WITH THE PASSAGE OF A WEAK FRONTAL BOUNDARY. TUESDAY CLOUDS
WILL REMAIN OVER WESTERN WYOMING AND THE NEBRASKA PANHANDLE INTO
THE AFTERNOON. POPS WILL DECREASE WITH A STABLE AIRMASS SLIDING
INTO THE CWA.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 152 PM MDT SUN SEP 27 2015
WEDNESDAY-THURSDAY:
THE MODELS ARE IN PRETTY GOOD AGREEMENT DURING THIS TIMEFRAME WITH
THE UPPER LEVEL RIDGE SNEAKING IN BETWEEN THE UPPER LEVEL TROF IN
THE EAST AND THE TROF IN THE PACIFIC NORTHWEST. THIS WILL CONTINUE
TO PROVIDE MILD CONDITIONS TO THE AREA WITH LITTLE OR NO CHANCES
OF PRECIP. THE WIND IS EXPECTED TO BE LIGHT AND VARIABLE ON
WEDNESDAY...BUT THE WIND/DEWPOINTS WILL BEGIN TO INCREASE FROM THE
EAST-SOUTHEAST ON THURSDAY AS THE PACIFIC UPPER LEVEL WAVE
APPROACHES IDAHO AND NORTHERN UTAH.
FRIDAY-SUNDAY:
LOTS OF UNCERTAINTY ON HOW THINGS ARE GOING TO PAN OUT DURING
THIS TIMEFRAME. THE MAIN QUESTION WILL BE WHETHER OR NOT THIS
PACIFIC TROF WILL SHEAR OUT AS IT MOVES INTO THE ROCKIES.
CURRENTLY...THE CANADIAN SOLUTION IS PROGGING THIS WAVE TO LIFT
NORTHEAST INTO NORTHERN PLAINS FRIDAY INTO SATURDAY. THE ECMWF/GFS
SOLUTIONS ARE SHOWING THE WAVE STALLING OVER WYOMING/NORTHERN
COLORADO/WESTERN NEBRASKA AND THEN SPENDING MOST OF ITS TIME
BRINGING BENEFICIAL RAINFALL TO THE AREA FRIDAY AND SATURDAY.
MEANWHILE...THE GEFS/NAEFS SOLUTIONS ARE SHOWING THE WAVE LIFTING
NORTHEAST TO THE NORTHERN PLAINS SIMILAR TO THE CANADIAN SOLUTION
WHICH MAY KEEP THE BEST CHANCES OF RAIN IN OUR NORTHERN ZONES. AT
THIS POINT...WE ARE FAVORING THE ENSEMBLE APPROACH WHICH KEEPS THE
BEST CHANCES OF PRECIP. ALONG AND NORTHEAST OF A DOUGLAS TO
SCOTTSBLUFF LINE. THIS MAY ALSO BRING MORE WIND TO THE AREA IF
THIS SYSTEM STAYS FURTHER NORTH. HOWEVER...IF THIS SYSTEM DIGS
FURTHER SOUTH AS THE GFS SUGGESTS WE MAY END UP WITH VERY COOL AND
RAINY CONDITIONS THIS WEEKEND WITH PERHAPS SOME SNOW IN THE
MOUNTAINS.
REGARDLESS OF WHERE THE TRACK IS...CLOUDY AND COOLER CONDITIONS
ARE ON TAP FOR THIS WEEKEND WITH HIGHS IN THE LOW TO MID 60S WITH
EVEN 50S IN THE LARAMIE RANGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1037 PM MDT SUN SEP 27 2015
VFR CONDITIONS FOR ALL SOUTHEAST WYOMING AND NEBRASKA PANHANDLE
AIRPORTS TONIGHT INTO MONDAY MORNING. HRRR GUIDANCE BEGINNING TO
INDICATE SOME FOG/IFR IN THE PLATTE RIVER VALLEY NEAR KBFF TOWARDS
12Z. NOT A FAVORABLE WIND DIRECTION THOUGH...SO DID NOT INCLUDE IN
THE 06Z TAF FOR KBFF. WILL SEE A CHANGE THOUGH MONDAY AFTERNOON
AS WE SEE NORTHEASTERLY UPSLOPING WINDS EAST OF THE LARAMIE RANGE.
CONTINUED THE TREND DOWN ON CEILINGS MONDAY AFTERNOON. WILL
LIKELY SEE IFR/LIFR CONDITIONS MONDAY EVENING FOR MUCH OF THE
PANHANDLE AND AIRPORTS EAST OF THE LARAMIE RANGE THROUGH TUESDAY.
&&
.FIRE WEATHER...
ISSUED AT 342 PM MDT SUN SEP 27 2015
FIRE WEATHER CONCERNS WILL BE MINIMAL THROUGH THIS WEEK.
A COLD FRONT WILL BRING COOLER TEMPERATURES TO THE AREA
TOMORROW AND TUESDAY ALONG WITH HIGHER MINIMUM RELATIVE
HUMIDITIES. WINDS WILL ALSO GENERALLY BE ON THE LIGHTER
SIDE BOTH MONDAY AND TUESDAY.
WARMER MIDWEEK WITH BREEZY CONDITIONS. MINIMUM RELATIVE HUMIDITY
VALUES MAY DROP TO AROUND 20 PERCENT THURSDAY AFTERNOON WEST OF
THE LARAMIE RANGE WITH NEAR CRITICAL FIRE WEATHER CONDITIONS. BY
FRIDAY AND SATURDAY IT IS LOOKING MORE LIKELY THAT A WEATHER
DISTURBANCE WILL BRING WIDESPREAD PRECIPITATION TO THE AREA WITH
SNOW INTO THE MOUNTAINS OF SOUTHEAST WYOMING.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...SML/KC
LONG TERM...REC
AVIATION...GCC
FIRE WEATHER...SML
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
354 AM CDT WED SEP 30 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 307 AM CDT WED SEP 30 2015
TODAY AND TONIGHT...SPRINKLES SHOULD EXIT THE FCST AREA BY OR AROUND
15Z ACCORDING TO THE RAP MODEL. SOUTH WINDS KEEP MOISTURE IN PLACE
ACROSS WRN NEB TODAY AND TONIGHT WITH MIXING PROCESSES PRODUCING
PARTLY CLOUDY SKIES. STRATUS SHOULD RETURN TONIGHT ACCORDING TO THE
SREF MODEL.
HIGHS IN THE 60S ARE IN PLACE TODAY WITH COOL AIR RECYCLING
NORTHWARD. LOWS IN THE 50S FOLLOW TONIGHT WITH THE EXPECTED CLOUD
COVER.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 307 AM CDT WED SEP 30 2015
AN UPPER LEVEL BLOCKING PATTERN EXPECTED TO PERSIST THROUGH THE
WEEKEND INTO EARLY NEXT WEEK. THIS WILL CONSIST OF A LONG WAVE
TROUGH ACROSS THE WESTERN CONUS...AN UPPER RIDGE ACROSS THE GREAT
LAKES AND EASTERN CANADA...AND A CUT OFF UPPER LEVEL LOW ACROSS
THE SOUTHEAST CONUS. EXPECT A SYSTEM TO EJECT EAST FROM THE
WESTERN CONUS LONG WAVE TROUGH INTO THE CENTRAL AND NORTHERN
PLAINS FRIDAY INTO SATURDAY...WITH THE ENTIRE LONG WAVE TROUGH TO
TRANSLATE EAST INTO THE CENTRAL AND NORTHERN PLAINS EARLY NEXT
WEEK AS THE UPPER PATTERN FINALLY BECOMES A BIT MORE PROGRESSIVE.
AS MENTIONED A SHORTWAVE TROUGH WILL EJECT EAST INTO THE REGION
FRIDAY INTO SATURDAY...THEN WEAKEN AND DISSIPATE SUNDAY AS IT
ENCOUNTERS THE STRONG UPPER LEVEL RIDGING ANCHORED ACROSS THE
GREAT LAKES/EASTERN CANADA. MODELS CONTINUE TO TREND SLOWER WITH
THIS SYSTEM...AND HAVE DELAYED THE ONSET OF RAIN UNTIL THURSDAY
NIGHT ACROSS NORTHWEST NEBRASKA. EXPECT RAIN TO SPREAD EAST
FRIDAY...WITH THE HEAVIEST MOST CONCENTRATED PERIOD OF RAIN TO
FALL FRIDAY NIGHT. DRY AIR IN THE LOWER LEVELS OF THE ATMOSPHERE
WILL BE CIRCULATING INTO EASTERN AND CENTRAL NEBRASKA OFF THE HIGH
ACROSS THE GREAT LAKES AND EASTERN CANADA. THIS WILL DELAY THE
RAIN UNTIL POSSIBLY FRIDAY NIGHT FOR AREAS AROUND
ONEILL...BARTLETT AND EWING.
THIS DRY AIR MAKES FOR A DIFFICULT FORECAST IN REGARDS TO STRATUS
CLOUD COVER. IT APPEARS THAT ENOUGH OF THE DRY AIR WILL MIX INTO
WESTERN NEBRASKA...AND HELP TO THIN AND BREAK UP THE STRATUS CLOUD
DECK THURSDAY AFTERNOON. FARTHER EAST...LITTLE IN THE WAY OF
STRATUS CLOUD COVER IS EXPECTED ACROSS CENTRAL AND NORTH CENTRAL
NEBRASKA WHERE THE DRY AIR LAYER WILL BE DEEPER. WITH THE ARRIVAL
OF THE SHORTWAVE TROUGH FRIDAY...MIDDLE AND HIGH CLOUDS WILL
DEVELOP AND OVERSPREAD THE AREA. IN ADDITION...THE LOW LEVELS WILL
REMAIN MOIST ENOUGH THAT A LOW CLOUD STRATUS DECK SHOULD REMAIN IN
PLACE THROUGH THE DAY ACROSS FAR WESTERN NEBRASKA AND THE
PANHANDLE. STILL EXPECTING THE DRIER AIR TO KEEP STRATUS TO A
MINIMUM FARTHER EAST. BY FRIDAY NIGHT INTO SATURDAY...ALL AREAS
WILL SEE THE LOWER LEVELS MOISTEN WITH A SOLID OVERCAST.
FOR THURSDAY AND FRIDAY...EXPECT THE COOLER HIGH TEMPERATURES TO
RESIDE ALONG AND WEST OF HIGHWAY 83 WHERE MORE CLOUD COVER IS
EXPECTED. THEN ON SATURDAY EXPECT A RAW DAY ACROSS ALL OF THE
AREA...WITH HIGHS BARELY REACHING INTO THE 50S DUE TO CLOUDS AND
COOL EAST/SOUTHEAST LOW LEVEL FLOW.
EARLY NEXT WEEK THE LONG WAVE TROUGH MIGRATES EAST BUT DAMPENS AS IT
MOVES INTO THE CENTRAL AND NORTHERN PLAINS. FOR NOW AT LEAST A LOW
CHANCE POP FOR SHOWERS SEEMS WARRANTED WITH THE ARRIVAL OF THE
TROUGH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1137 PM CDT TUE SEP 29 2015
CURRENT OBSERVATIONS AND SATELLITE IMAGERY SHOW CEILINGS IN WESTERN
NEBRASKA LESS THAN 3000 FEET AGL ALONG AND WEST OF A VTN-TIF-MCK
LINE. SHORT RANGE PROJECTION...INCLUDING THE RAPID REFRESH CYCLE AND
THE NORTH AMERICAN MODEL...INDICATE THAT THE LOWER CEILINGS RE NIT
LIKELY TO DEVELOP EAST OF THAT LINE. THUS THE PROBABILITY OF
INSTRUMENT METEOROLOGICAL CONDITIONS VTN-LBF AND EAST IS LOW. AS A
RESULT...WE WILL KEEP THE FORECAST CEILINGS FOR LBF AND VTN ABOVE
1000 FEET AGL BUT BELOW 3000 FEET AGL.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...SPRINGER
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
342 AM CDT WED SEP 30 2015
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 313 AM CDT WED SEP 30 2015
LATEST WATER VAPOR IMAGERY AND RAP 500MB HEIGHT ANALYSIS SHOWS LARGE
RIDGE OF HIGH PRESSURE EXTENDING FROM NORTHWESTERN MEXICO INTO
BRITISH COLUMBIA/ALBERTA. DOWNSTREAM...A LARGE TROUGH EXTENDS FROM
HUDSON`S BAY TO EASTERN TEXAS PUTTING OUR REGION IN MODEST
NORTHWESTERLY FLOW. A WEAK SHORTWAVE OVER SOUTHEAST SOUTH DAKOTA HAS
PROVEN TO BE ENOUGH FORCING TO SPAWN A FEW RADAR RETURNS ACROSS
SOUTHEAST SOUTH DAKOTA AND NORTHEAST NEBRASKA. NOT ANTICIPATING
MUCH...IF ANYTHING...TO REACH THE GROUND AS OBS INDICATE ALL MID
CLOUDS. LOW LEVELS WILL REMAIN QUITE DRY WITH SFC HIGH PRESSURE
ANCHORED FROM QUEBEC SOUTHWESTWARD TO THE GREAT PLAINS.
THE ABOVE MENTIONED MID LEVEL SHORTWAVE WILL CONTINUE TO DROP
SOUTHEAST INTO MISSOURI EARLY TODAY. MID CLOUDS SHOULD DIMINISH
LATER THIS MORNING BUT HIGHS WILL REMAIN SLIGHTLY BELOW NORMAL IN
THE MID TO UPPER 60S.
THE UPPER RIDGE AXIS WILL SHIFT EAST TOWARD THE FORECAST AREA BY
THE WEEKEND AHEAD OF A LARGE APPROACHING UPPER TROUGH.
TEMPERATURES WILL REMAIN COOLER THAN NORMAL FOR THIS TIME OF THE
YEAR WITH CONTINUED EASTERLY LOW LEVEL FLOW.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 313 AM CDT WED SEP 30 2015
PCPN CHANCES BEGIN TO INCREASE ACROSS WESTERN AND CENTRAL NEBRASKA
FRIDAY NIGHT IN ADVANCE OF APPROACHING UPPER TROUGH. OVERALL
TREND HAS BEEN TO LOWER POPS IN OUR AREA AS BEST FORCING
ASSOCIATED WITH THE UPPER TROUGH REMAINS TO OUR WEST AND NORTH.
DRY AIR TO OUR EAST WILL BE PROBLEMATIC AND SHOULD KEEP CONDITIONS
MOSTLY DRY ACROSS THE EASTERN CWA.
THE BASE OF THE WESTERN UPPER TROUGH WILL ROUND THE FOUR CORNERS
REGION LATE IN THE EXTENDED. THIS COULD BRING PCPN TO THE AREA BY
EARLY TO MID NEXT WEEK HOWEVER MANY FORECAST UNCERTAINTIES
REMAIN.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1157 PM CDT TUE SEP 29 2015
VFR CONDITIONS WILL CONTINUE THROUGH THE PERIOD.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...KERN
LONG TERM...KERN
AVIATION...KG
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
334 AM CDT WED SEP 30 2015
.DISCUSSION...SHORTWAVE PUSHING EASTWARD ACROSS WESTERN KENTUCKY AND
MIDDLE TENNESSEE EARLY THIS MORNING WAS ACCOMPANIED BY AN AREA OF
SCATTERED TO NUMEROUS SHOWERS OVER WESTERN KENTUCKY. THIS AREA OF
SHOWERS HAS BEEN WORKING ITS WAY SOUTHWARD TOWARD NORTHERN MIDDLE
TENNESSEE DURING THE NIGHT, AND WILL LIKELY ROLL INTO OUR AREA
OVER THE NEXT SEVERAL HOURS. IN ADDITION, EXPECT ADDITIONAL
SHOWERS TO DEVELOP OVER CENTRAL AND EASTERN PARTS OF THE MID-STATE
AS THE MORNING WEARS ON, AND AS SFC DEW POINT FRONT PUSHES INTO
WESTERN AREAS.
.SHORT TERM...
ANOTHER SHORTWAVE DIVES SOUTHEASTWARD INTO THE OHIO RIVER VALLEY
THIS AFTERNOON, DEEPENING THE UPPER TROUGH OVER THE TENNESSEE
VALLEY, AND KEEPING SFC DEW POINT FRONT PARKED GENERALLY FROM NEAR
WAYNESBORO TO CELINA, WITH SCATTERED TO NUMEROUS SHOWERS
CONTINUING EAST OF THE BOUNDARY, WITH ONLY A SLIGHT CHANCE OF
MEASURABLE RAIN BEHIND THE BOUNDARY.
BELIEVE HRRR MODEL IS DOING A PRETTY GOOD JOB WITH PRECIP PATTERN
TODAY AND HAVE FASHIONED OUR QPF FORECAST FOR TODAY IN LINE WITH
HRRR PREDICTION.
EXPECT ANOTHER DAY OF SEASONABLY COOL TEMPERATURES, ESPECIALLY
OVER WESTERN AND NORTH-CENTRAL AREAS, WHERE TEMPERATURES ARE ONLY
EXPECTED TO RISE A FEW DEGREES ABOVE MORNING LOWS. THE HIGH IN
PORTLAND, DICKSON AND CLARKSVILLE IS ONLY EXPECTED TO BE AROUND 69
OR 70 DEGREES. FURTHER SOUTH AND EAST, EXPECT TEMPERATURES TO MAKE
A SLIGHTLY BETTER RECOVERY, WITH AFTERNOON HIGHS TOPPING OUR
MAINLY IN THE LOWER TO MIDDLE 70S.
MODELS ARE CONSISTENT WITH THE IDEA OF DEEPENING TENNESSEE VALLEY
TROUGH EVEN FURTHER TONIGHT, WITH UPPER LOW CLOSING OFF AROUND BNA
BY 18 TOMORROW. THIS MEANS CLOUDS AND SHOWERS WILL STAY WITH US
THROUGH THURSDAY, WITH THE BEST CHANCE FOR SHOWERS OVER EASTERN
AREAS.
AS CLOSED UPPER LOW SINKS ALMOST DUE SOUTHWARD ON FRIDAY, BELIEVE
AREA OF SCATTERED TO NUMEROUS SHOWERS WILL ROTATE WESTWARD ALONG
THE NORTHERN PERIPHERY OF THE LOW, WITH RAIN CHANCES ACTUALLY
INCREASING A BIT IN THE MID STATE THURSDAY NIGHT AND FRIDAY.
OUR FRIENDLY UPPER LOW JUST HANGS AROUND THE SOUTHEASTERN UNITED
STATES THROUGH THE WEEKEND, EVENTUALLY MIGRATING INTO THE
CAROLINAS. THIS MEANS CLOUDS WILL BE STICKING WITH US THROUGH THE
PERIOD, ALONG WITH A CONTINUED CHANCE FOR SHOWERS.
TEMPERATURES WILL BE QUITE COOL LATE THIS WEEK AND OVER THE
WEEKEND, WITH CLOUDS AND RAIN HELPING TO HOLD OUR AFTERNOON HIGHS
ONLY IN THE 60S.
&&
.LONG TERM...UPPER LOW EVENTUALLY ROTATES NORTHEASTWARD ALONG THE
ATLANTIC SEABOARD DURING THE EARLY TO MIDDLE PART OF NEXT WEEK,
ALLOWING FOR A DRYING TREND. HIGHS WILL BE MAINLY IN THE LOWER TO
MIDDLE 70S, WITH LOWS IN THE UPPER 40S TO MIDDLE 50S.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 73 59 68 54 / 40 10 20 40
CLARKSVILLE 71 56 68 52 / 40 10 10 20
CROSSVILLE 72 57 62 52 / 60 30 50 60
COLUMBIA 74 59 70 52 / 40 10 20 30
LAWRENCEBURG 75 59 70 53 / 40 10 10 20
WAVERLY 72 58 70 52 / 40 10 10 20
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
19
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1144 PM MDT TUE SEP 29 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 350 PM MDT TUE SEP 29 2015
ISOLATED SHOWERS AND WEAK THUNDERSTORMS WILL TRY TO SHIFT INTO THE
PLAINS THIS EVENING. LOW LEVEL CAP WILL KEEP THUNDERSTORMS FROM
MAKING IT VERY FAR EAST. MOST THUNDERSTORM ACTIVITY OR AT LEAST
ANY STRONGER THUNDERSTORMS SHOULD DIE OFF AROUND INTERSTATE 25.
THERE IS THE POTENTIAL FOR SOME SHOWERS AND THUNDERSTORMS TO
BECOME ELEVATED AS THE LEFT EXIT REGION OF AN UPPER LEVEL JET
SLIDES INTO THE AREA THIS EVENING. HRRR MODEL...WHICH HAS HANDLED
SHOWER AND THUNDERSTORM ACTIVITY FAIRLY WELL THE LAST COUPLE DAYS
DOES DEVELOP ELEVATED CONVECTION. BASED ON THE HRRR THE ACTIVITY
OVER THE SOUTHERN LARAMIE RANGE WILL DIE OFF AS IT MOVES INTO
SOUTHEAST WYOMING/NORTHEAST COLORADO WHILE ANOTHER BATCH OF
ACTIVITY WILL FORM OVER THE NORTHERN LARAMIE RANGE LATE THIS
AFTERNOON AND THEN MOVE SOUTHEAST INTO THE SOUTHERN NEBRASKA
PANHANDLE BY MID EVENING. FORECAST POPS GENERALLY REPRESENT THE
HRRR SOLUTION THROUGH THIS EVENING. SEVERE THUNDERSTORM ARE VERY
UNLIKELY BUT A FEW WINDS GUSTS UPWARDS OF 50 MPH AND PEA SIZED
HAIL CAN NOT BE RULED OUT WITH A FEW STRONGER THUNDERSTORMS.
LOW STRATUS AND PATCHY FOG WILL REDEVELOP OVER MUCH OF THE PLAINS
THIS EVENING. NOT CONFIDENT IN HOW FAR WEST AND NORTH THE STRATUS
AND FOG WILL MAKE IT BUT IT COULD PARALLEL THE LARAMIE RANGE FOR A
WHILE TONIGHT. WINDS SHOULD BECOME WEST ALONG THE LARAMIE RANGE
AFTER MIDNIGHT WHICH WILL BEGIN TO ERODE THE WESTERN FLANKS OF
FOG AND STRATUS. COULD ALSO SEE SOME DRIZZLE TONIGHT INTO THE
NEBRASKA PANHANDLE AS THERE WILL BE AN AREA OF WEAK THETAE
ADVECTION NEAR THE TOP OF A SHALLOW SATURATED INVERSION. MOST OF
THE FOG/LOW STRATUS/DRIZZLE WILL ERODE EASTWARD INTO THE PLAINS
THROUGH THE DAYLIGHT HOURS TOMORROW BUT PLACES LIKE ALLIANCE AND
SIDNEY NEBRASKA MAY NOT SEE THE SUN TOMORROW AS A LOW LEVEL
INVERSION MAY HOLD THE STRATUS IN PLACE.
CHANCES FOR THUNDERSTORMS WILL BE MINIMAL WEDNESDAY WITH THE MAIN
CHANCES IN AND NEAR THE SNOWY RANGE AND SIERRA MADRE RANGE. THE
MODELS ARE SHOWING SURFACE BASED CAPES OF 500-1000 J/KG INTO THE
PLAINS WEDNESDAY AFTERNOON. THE MAIN QUESTION IS WHETHER OR NOT
THE CAP WILL HOLD AND IF THERE WILL BE ANY UPPER LEVEL SUPPORT IN
PLACE. NOT CONFIDENT THERE WILL BE STORMS INTO THE PLAINS BUT IT
WILL BE SOMETHING TO WATCH.
MORE FOG AND LOW STRATUS LIKELY FOR THE PLAINS WEDNESDAY NIGHT
INTO THURSDAY MORNING. SMALL CHANCES FOR SHOWERS AND
THUNDERSTORMS AGAIN THURSDAY AFTERNOON.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 300 PM MDT TUE SEP 29 2015
RAIN AND SHOWERS SHOULD SPREAD ACROSS THE CWA DURING THE DAY
FRIDAY AS THE WESTERN CONUS UPPER TROF MOVES EAST AND PIVOTS
ACROSS THE CWA THROUGH FRIDAY NIGHT. SOME SNOW STILL POSSIBLE OVER
THE HIGHER MTNS BUT NOT A LOT OF COLD AIR WITH THIS SYSTEM SO ANY
ACCUMULATIONS INTO SAT MORNING SHOULD BE ON THE LOW SIDE. SOME
LULL IN THE PCPN ON SATURDAY BEFORE NEXT IMPULSE IN THE FLOW
ROTATES ACROSS SAT NIGHT BRINGING ANOTHER ROUND OF PCPN. IN THE
MEANTIME A POTENT UPPER LOW WILL DROP DOWN ALONG THE WEST COAST
SAT NIGHT AND SUNDAY BEFORE BEGINNING A SLOW DRIFT NORTHEAST EARLY
NEXT WEEK. SHORT RIDGING WILL BUILD OVER THE CWA SUNDAY DRYING
THINGS OUT AND ALLOWING FOR MILDER TEMPS AFTER A COOL DAY
SATURDAY. THIS SHOULD CONTINUE THROUGH MOST OF MONDAY BEFORE THE
UPPER LOW BEGINS SPREADING PCPN BACK OVER THE CWA MONDAY NIGHT
INTO TUESDAY. AGAIN SNOWS LOOK TO BE CONFINED TO THE HIGHER MTN
ELEVATIONS. TEMPERATURES REMAINING MILD...CLOSE TO SEASONAL
AVERAGES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1135 PM MDT TUE SEP 29 2015
ISOLATED SHOWERS AND THUNDERSTORMS OVER THE WESTERN NEB PANHANDLE
WILL SLOWLY COME TO AN END BY LATE TONIGHT. MVFR/IFR CEILINGS AND
VISIBILITIES ARE ALREADY TAKING SHAPE ALONG THE I80 CORRIDOR FROM
KCYS TO KSNY...AND WILL LIKELY BECOME MORE WIDESPREAD DURING THE
OVERNIGHT. MVFR CONDITIONS COULD PERSIST OVER SOME OF THE WESTERN
NEBRASKA TERMINALS FOR MUCH OF THE DAY ON WED. ASIDE FROM FOG AT
KCYS BETWEEN 06Z AND 08Z TONIGHT...GENERALLY VFR CONDITIONS WILL
OCCUR OVER SOUTHEAST WYOMING THROUGH THE PERIOD.
&&
.FIRE WEATHER...
ISSUED AT 350 PM MDT TUE SEP 29 2015
HUMIDITY VALUES WILL DIP INTO THE 20 TO 25 PERCENT RANGE OVER SOUTH
CENTRAL WYOMING WEDNESDAY AND THURSDAY AFTERNOON WITH WIND GUSTS
BETWEEN 20 TO 25 MPH. THAT WILL BE THE ONLY AREA WITH ANY FIRE
WEATHER CONCERNS THIS WEEK. OTHERWISE RELATIVE HUMIDITY VALUES
WILL REMAIN ON THE HIGH SIDE OVER THE PLAINS THIS WEEK. AN UPPER
LEVEL LOW IS STILL EXPECTED TO IMPACT THE REGION LATE FRIDAY THROUGH
SATURDAY. WIDESPREAD WETTING RAIN IS LIKELY ALONG WITH SNOW INTO THE
MOUNTAINS OF SOUTHEAST WYOMING. MOST SNOW ACCUMULATIONS WILL BE ABOVE
9000 FEET BUT COULD SEE SOME SNOW AS LOW AS 8000 FEET.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...SML
LONG TERM...RE
AVIATION...CLH
FIRE WEATHER...SML
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
451 AM PDT WED SEP 30 2015
.SYNOPSIS...A CHANCE OF SHOWERS OR SPRINKLES SOUTH OF SAN
FRANCISCO TODAY THROUGH THURSDAY MORNING AS MOISTURE MOVES
ONSHORE. A WARMING AND DRYING TREND FRIDAY AND SATURDAY AS HIGH
PRESSURE BUILDS BEHIND THE TROUGH. ANOTHER COLD TROUGH WILL DIVE
DOWN THE COAST SUNDAY BRINGING A SHOT OF COOLER TEMPERATURES AND A
SLIGHT CHANCE OF SHOWERS. DRY AND SEASONABLE WEATHER RETURNS EARLY
NEXT WEEK.
&&
.DISCUSSION...AS OF 3:28 AM PDT WEDNESDAY...FORECAST FOCUS WILL
DEAL WITH SOME SHOWER CHANCES THE NEXT 24 HOURS AND THEN A TROUGH
PASSAGE ON SUNDAY.
IN THE SHORT TERM...PLENTY OF HIGH CLOUDS CONTINUE TO STREAM OVER
THE BAY AREA AND CENTRAL CALIFORNIA WITH AN UPPER LOW CENTERED OUT
NEAR 35N/130W. THE ECMWF MODEL WAS THE FIRST TO SUGGEST SOME
LIGHT SHOWERS COULD BREAK OUT TODAY...MAINLY FOR AREAS SOUTH OF
SAN FRANCISCO. STILL NOT GETTING A LOT OF BUY-IN FROM THE NAM AND
GFS ALTHOUGH THE JUST RECEIVED 06Z GFS IS SHOWING SOME LIGHT QPF.
HOWEVER THE RAP AND HRRR MESOSCALE MODELS ARE GENERATING SOME
LIGHT QPF THROUGH THE DAY. IR CLOUD TOPS SHOWING -40 CELSIUS WITH
THE KMUX RADAR STARTING TO PICK UP SOME RETURNS OFFSHORE WEST OF
BIG SUR. FORECAST FOR TODAY WILL SHOW SLIGHT CHANCE OF SHOWERS OR
SPRINKLES...MAINLY FOCUSED OVER SANTA CRUZ COUNTY AND NORTHERN
MONTEREY/SAN BENITO. OFFICIAL FORECAST WILL KEEP QPF NUMBERS VERY
LIGHT ON THE ORDER OF A FEW HUNDREDTHS.
UPPER TROUGH AXIS...WEAK SURFACE BOUNDARY AND COOL ADVECTION ALOFT
WILL PRODUCE SOME WEAK LIFT AND INSTABILITY OVERNIGHT INTO
THURSDAY MORNING SO WILL KEEP THE SLIGHT CHANCE OF SHOWERS GOING
THROUGH THE PERIOD. THE ECMWF CONTINUES TO BE THE WETTEST MODEL
SHOWING 0.25 BY THURSDAY MORNING OVER AN AREA FROM SANTA CRUZ TO
MT HAMILTON AND SOUTHWARD TOWARDS MONTEREY AND HOLLISTER. PRECIP
AMOUNTS WILL MORE LIKELY BE SPOTTY AND EXPECTING HIGHEST TOTALS
AROUND 0.10 ON AVERAGE. FORECAST REMAINS DRY FOR THE NORTH BAY THE
NEXT 24 HOURS.
BY THURSDAY AFTERNOON THE PARENT LOW WILL MOVE INLAND AND HIGH
PRESSURE WILL BEGIN TO BUILD AS TROUGH AXIS SHIFTS INLAND. THIS
WILL LEAD TO A NOTED WARMING AND DRYING TREND FOR FRIDAY...LASTING
RIGHT THROUGH SATURDAY AFTERNOON. EXPECT WIDESPREAD READINGS FROM
THE UPPER 70S THROUGH MID 80S.
BY SATURDAY NIGHT A COLD UPPER LOW WILL DROP DOWN FROM BRITISH
COLUMBIA. THE CORE OF THE SYSTEM LOOKS VERY DRY SO THE MAIN
IMPACT WILL BE COOLER TEMPERATURES AND SOME GUSTY WINDS. COOLER
TEMPERATURES ON SUNDAY AS THE LOW PASSES OVER THE REGION. THERE IS
A SLIGHT CHANCE OF A SHOWER...MAINLY OVER THE EASTERN HILLS OF
SANTA CLARA AND SAN BENITO COUNTY DUE TO STEEP LAPSE RATES ALOFT
BUT MOISTURE IS LACKING WITH THE SYSTEM AND ANY PRECIP CHANCES
LOOK SLIGHT AT BEST.
THE LOW MOVES INLAND BY SUNDAY NIGHT...LEADING TO A RETURN OF DRY
AND SEASONABLE WEATHER MONDAY THROUGH WEDS OF NEXT WEEK.
&&
.AVIATION...AS OF 4:45 AM PDT WEDNESDAY...FT ORD PROFILER SHOWS NO
SIGN OF AN INVERSION. PATCHY LOW CLOUDS HAVE DEVELOPED BUT VFR
CONDITIONS ARE EXPECTED TODAY WITH MID AND HIGH CLOUDS. RADAR IS
PICKING UPS A FEW SHOWERS SW OF THE MRY BAY AREA WHICH MAY AFFECT
THE MRY BAY AREA AFTER 12Z AND THE SFO BAY AREA AFTER 16Z.
VICINITY OF KSFO...VFR WITH MID AND HIGH LEVEL CLOUDINESS. ISOLATED
SHOWERS POSSIBLE 16Z-03Z.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR WITH MID AND HIGH CLOUDINESS.
ISOLATED SHOWERS POSSIBLE THROUGH 20Z.
&&
.MARINE...AS OF 4:45 AM PDT WEDNESDAY...WEAK LOW PRESSURE OFF THE
COAST WILL KEEP LIGHT WINDS THROUGH THURSDAY. HIGH PRESSURE WILL
BUILD OVER THE EASTERN PACIFIC FRIDAY AND SATURDAY RESULTING IN
INCREASING NORTHWEST WINDS.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...NONE.
$$
PUBLIC FORECAST: RWW
AVIATION: W PI
MARINE: W PI
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FOLLOW US ON FACEBOOK AND TWITTER AT:
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
328 AM PDT WED SEP 30 2015
.SYNOPSIS...A CHANCE OF SHOWERS OR SPRINKLES SOUTH OF SAN
FRANCISCO TODAY THROUGH THURSDAY MORNING AS MOISTURE MOVES
ONSHORE. A WARMING AND DRYING TREND FRIDAY AND SATURDAY AS HIGH
PRESSURE BUILDS BEHIND THE TROUGH. ANOTHER COLD TROUGH WILL DIVE
DOWN THE COAST SUNDAY BRINGING A SHOT OF COOLER TEMPERATURES AND A
SLIGHT CHANCE OF SHOWERS. DRY AND SEASONABLE WEATHER RETURNS EARLY
NEXT WEEK.
&&
.DISCUSSION...AS OF 3:28 AM PDT WEDNESDAY...FORECAST FOCUS WILL
DEAL WITH SOME SHOWER CHANCES THE NEXT 24 HOURS AND THEN A TROUGH
PASSAGE ON SUNDAY.
IN THE SHORT TERM...PLENTY OF HIGH CLOUDS CONTINUE TO STREAM OVER
THE BAY AREA AND CENTRAL CALIFORNIA WITH AN UPPER LOW CENTERED OUT
NEAR 35N/130W. THE ECMWF MODEL WAS THE FIRST TO SUGGEST SOME
LIGHT SHOWERS COULD BREAK OUT TODAY...MAINLY FOR AREAS SOUTH OF
SAN FRANCISCO. STILL NOT GETTING A LOT OF BUY-IN FROM THE NAM AND
GFS ALTHOUGH THE JUST RECEIVED 06Z GFS IS SHOWING SOME LIGHT QPF.
HOWEVER THE RAP AND HRRR MESOSCALE MODELS ARE GENERATING SOME
LIGHT QPF THROUGH THE DAY. IR CLOUD TOPS SHOWING -40 CELSIUS WITH
THE KMUX RADAR STARTING TO PICK UP SOME RETURNS OFFSHORE WEST OF
BIG SUR. FORECAST FOR TODAY WILL SHOW SLIGHT CHANCE OF SHOWERS OR
SPRINKLES...MAINLY FOCUSED OVER SANTA CRUZ COUNTY AND NORTHERN
MONTEREY/SAN BENITO. OFFICIAL FORECAST WILL KEEP QPF NUMBERS VERY
LIGHT ON THE ORDER OF A FEW HUNDREDTHS.
UPPER TROUGH AXIS...WEAK SURFACE BOUNDARY AND COOL ADVECTION ALOFT
WILL PRODUCE SOME WEAK LIFT AND INSTABILITY OVERNIGHT INTO
THURSDAY MORNING SO WILL KEEP THE SLIGHT CHANCE OF SHOWERS GOING
THROUGH THE PERIOD. THE ECMWF CONTINUES TO BE THE WETTEST MODEL
SHOWING 0.25 BY THURSDAY MORNING OVER AN AREA FROM SANTA CRUZ TO
MT HAMILTON AND SOUTHWARD TOWARDS MONTEREY AND HOLLISTER. PRECIP
AMOUNTS WILL MORE LIKELY BE SPOTTY AND EXPECTING HIGHEST TOTALS
AROUND 0.10 ON AVERAGE. FORECAST REMAINS DRY FOR THE NORTH BAY THE
NEXT 24 HOURS.
BY THURSDAY AFTERNOON THE PARENT LOW WILL MOVE INLAND AND HIGH
PRESSURE WILL BEGIN TO BUILD AS TROUGH AXIS SHIFTS INLAND. THIS
WILL LEAD TO A NOTED WARMING AND DRYING TREND FOR FRIDAY...LASTING
RIGHT THROUGH SATURDAY AFTERNOON. EXPECT WIDESPREAD READINGS FROM
THE UPPER 70S THROUGH MID 80S.
BY SATURDAY NIGHT A COLD UPPER LOW WILL DROP DOWN FROM BRITISH
COLUMBIA. THE CORE OF THE SYSTEM LOOKS VERY DRY SO THE MAIN
IMPACT WILL BE COOLER TEMPERATURES AND SOME GUSTY WINDS. COOLER
TEMPERATURES ON SUNDAY AS THE LOW PASSES OVER THE REGION. THERE IS
A SLIGHT CHANCE OF A SHOWER...MAINLY OVER THE EASTERN HILLS OF
SANTA CLARA AND SAN BENITO COUNTY DUE TO STEEP LAPSE RATES ALOFT
BUT MOISTURE IS LACKING WITH THE SYSTEM AND ANY PRECIP CHANCES
LOOK SLIGHT AT BEST.
THE LOW MOVES INLAND BY SUNDAY NIGHT...LEADING TO A RETURN OF DRY
AND SEASONABLE WEATHER MONDAY THROUGH WEDS OF NEXT WEEK.
&&
.AVIATION...AS OF 10:45 PM PDT TUESDAY...MID AND HIGH CLOUDS CONTINUE
OVER THE AREA THIS EVENING. STRATUS POSSIBLE TONIGHT BUT MARINE
INVERSIONS HAVE LIFTED AND WEAKENED THUS CLOUD BASES SHOULD BE
HIGHER END MVFR OR VFR OVERNIGHT. ISOLATED SHOWERS POSSIBLE LATE
TONIGHT AND WEDNESDAY AS CONTINUOUS STREAM OF MID LEVEL SUB-TROPICAL
MOISTURE...STEADY 500 MB HEIGHT COOLING...AND MOSTLY WEAK MID LEVEL
DYNAMICS INCREASINGLY INTERACT.
VICINITY OF KSFO...MOSTLY MID AND HIGH CLOUD LAYERS THIS EVENING.
ISOLATED SHOWERS POSSIBLE LATE.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR/MVFR DURING THE PERIOD.
&&
.MARINE...AS OF 02:30 AM PDT WEDNESDAY...GENERALLY LIGHT WINDS AND
CALM SEAS ARE EXPECTED TO PERSIST ACROSS THE COASTAL WATERS
THROUGH WEDNESDAY AS A WEAK SURFACE PRESSURE GRADIENT RESIDES
ALONG THE COAST. THE SURFACE PRESSURE GRADIENT WILL STRENGTHEN
ALONG THE COAST BRINGING INCREASING NORTHWEST WINDS TO THE WATERS
BEGINNING THURSDAY AND PERSISTING INTO SATURDAY...THE STRONGEST
WINDS ARE EXPECTED TO OCCUR OVER THE NORTHERN WATERS.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...NONE.
$$
PUBLIC FORECAST: RWW
AVIATION: W PI
MARINE: W PI
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK AND TWITTER AT:
WWW.FACEBOOK.COM/NWSBAYAREA
WWW.TWITTER.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
938 AM MDT WED SEP 30 2015
.UPDATE...
ISSUED AT 938 AM MDT WED SEP 30 2015
AREAS OF FOG ON THE PLAINS HAS LIFTED. THERE IS STILL A
CONSIDERABLE STRATUS DECK ON THE FAR EASTERN PLAINS...WITH A FAIR
AMOUNT OF MID/UPPER LEVEL CLOUDS ELSEWHERE. THERE WILL BE SOME
BREAKS THROUGH THE DAY ALLOWING FOR SOME SURFACE HEATING.
HOWEVER...LOW LEVEL MOISTURE ALONG THE FRONT RANGE IS VERY THIN
AS EVIDENCED ON THE 12Z DENVER SOUNDING. AS A RESULT...MOST
CONVECTION WILL HAVE TO INITIATE OVER THE HIGH COUNTRY AND THEN
ATTEMPT TO DRIFT OFF THE FRONT RANGE LATE THIS AFTERNOON INTO THE
EARLY EVENING HOURS. WHERE THERE IS DEEPER LOW LEVEL MOISTURE ON
THE EASTERN PLAINS IT WILL BE TOO STABLE FOR ANY CONVECTION.
PREVIOUS FORECAST HANDLES THIS ALL QUITE WELL SO ONLY MINOR
ADJUSTMENTS AT THIS TIME.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 443 AM MDT WED SEP 30 2015
BAND OF MID/HIGH CLOUDINESS ASSOCIATED WITH THE JET WILL SHIFT
SLOWLY EASTWARD TODAY. AT THE SURFACE THERE IS A WEAK DENVER
CYCLONE...ACTUALLY MORE OF A SHEAR ZONE BETWEEN THE SOUTHEAST
WINDS ON THE PLAINS AND VERY LIGHT NORTH WINDS NEAR THE MOUNTAINS.
THIS FEATURE WILL LIKELY PERSIST THROUGH THE DAY...AND WILL
PROBABLY PROGRESS EASTWARD A BIT WITH TIME. THERE IS WIDESPREAD
STRATUS AND AREAS OF FOG EAST OF THIS BOUNDARY...WITH PATCHY FOG
JUST STARTING TO DEVELOP FURTHER WEST HINDERED BY THE HIGH
CLOUDS. THIS WILL EVENTUALLY SET UP A DECENT TEMPERATURE GRADIENT
WITH THE COOLER MOIST AIR OUT EAST...AND A LITTLE MIXING WITH
WARMER AND SLIGHTLY DRIER AIR AROUND DENVER. WITH MARGINAL
TEMPERATURES AND LITTLE CAPE OVER THE WESTERN PART OF THE
AREA...AND COOL TEMPERATURES IN THE EAST...EXPECT THAT SHOWERS
TODAY WILL BE DRIVEN BY THE JET. PROBLEM IS THE LACK OF MID LEVEL
MOISTURE WHICH MAY LIMIT THE ACTIVITY. HRRR SHOWS A NARROW BAND OF
WEAK CONVECTION OVER THE MOUNTAINS AT MIDDAY SHIFTING EAST INTO
THE PALMER DIVIDE AREA THIS AFTERNOON. BUT THE HRRR TENDS TO
OVERDO WEAK CONVECTION LIKE THIS. SHOULD BE CLOSE ENOUGH TO
INSTABILITY TO GET SOME SHOWERS OR STORMS OVER THE MOUNTAINS WITH
THE HELP OF SOME LIFT...LESS SURE ABOUT HOW MUCH WOULD MAKE IT
ONTO THE PLAINS. ONLY MINOR CHANGES TO THE EXISTING LOW POPS
MAINLY OVER THE MOUNTAINS...AND PALMER DIVIDE LATE IN THE DAY.
AS FOR TEMPERATURES...TRIMMED A COUPLE DEGREES OFF THE EASTERN
BORDER AREAS...OTHERWISE THEY LOOK GOOD. NEAR GUIDANCE TODAY AND A
LITTLE WARMER TONIGHT AS THERE WILL STILL BE LOTS OF CLOUD COVER.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 443 AM MDT WED SEP 30 2015
BIG DIFFERENCES IN THE MODELS PARTICULARLY WITH REGARD TO THE
POSITION/FORWARD PROGRESS OF THE BIG UPPER TROUGH DURING THE
FRI/SAT TIME FRAME. MODELS START OUT IN GOOD AGREEMENT BY SHIFTING
THE TALL UPPER RIDGE OVER COLORADO ON THURSDAY EAST OF THE STATE
BY FRIDAY MORNING. WARM SWLY/DOWNSLOPE FLOW AND PLENTY OF SUNSHINE
TO START THE DAY WILL HAVE LITTLE TROUBLE PUSHING TEMPS INTO THE
LOWER 80S ALONG THE FRONT RANGE BY AFTERNOON. NOT SO FARTHER EAST
ON THE PLAINS WHERE AREAS OF STRATUS AND FOG WILL LIKELY DELAY
WARMING UNTIL AFTERNOON RESULTING IN MAX TEMPS ONLY IN THE LOW/MID
70S OUT THERE. THE FOG ACRS LINCOLN...ERN ELBERT AND SRN PORTIONS
OF WASHINGTON COUNTIES EARLY THURSDAY COULD BE RATHER THICK AS
THIS AREA WILL BE SUBJECTED TO MOIST SELY BOUNDARY LAYER FLOW ALL
NIGHT. MEANWHILE DAYTIME HEATING COUPLED WITH MODEST MID-LEVEL
DESTABILIZATION COULD PRODUCE A FEW SHOWERS/T-SHOWERS OVER HIGHER
ELEVATIONS OF THE FRONT RANGE. THEN DURING THE EVENING HOURS...
CONTINUED ADVECTION OF LOW-LEVEL MOISTURE ON GUSTY SELY WINDS MAY
COMBINE WITH WEAK SHEAR/INSTABILITY ALONG A STALLED OUT SFC TROUGH
TO SPAWN A FEW WEAK T-STORMS ACROSS THE NERN CORNER OF THE STATE.
BUT WITH MINIMAL CAPE ANY STORMS THAT FORM WILL BE OF LITTLE
CONSEQUENCE.
ON FRIDAY..MODEL CONSENSUS SHOWS THE UPPER TROUGH TO OUR WEST
CLOSING OFF OVER NORTHERN UTAH AND MID-LEVEL SWLY FLOW OVER
COLORADO STRENGTHENING. MEANWHILE PRESSURE/HEIGHT FALLS ACRS
WYOMING IN THE PATH OF THE UPPER LOW AID IN STRENGTHENING THE SELY
LOW-LEVEL FLOW IN EASTERN COLORADO DURING THE DAY. MOISTURE
CONTINUES TO ADVECT UP INTO THE AREA RESULTING IN INCREASING CLOUD
COVER OVER THE MTNS FIRST...THEN OVER THE EASTERN SECTIONS OF THE
CWA THROUGH THE AFTERNOON. CLOSE IN TO THE FRONT RANGE SWLY/
DOWNSLOPE FLOW DURING THE MORNING WILL ALLOW SOLAR HEATING TO
PUSH TEMPS INTO THE LOWER 70S BY MIDDAY. THEN MODELS PARTICULARLY
THE NAM SHOW A DENVER CYCLONE FORMING NEAR DIA WITH STRENGTHENING
SELY WINDS ON THE PLAINS BY EARLY AFTERNOON. NOT LONG AFTER ITS
FORMATION MODELS SHOW A SHARP DENVER VORTICITY CONVERGENCE ZONE
SETTING UP EAST-SOUTHEAST OF DENVER...WITH THE NAM INDICATING SFC
BASED CAPES APPROACHING 2000 J/KG BY LATE AFTERNOON. SELY SFC
FLOW TOPPED BY STRENGTHENING SWLY FLOW ALOFT WILL PROVIDE A
FAVORABLE SHEAR PROFILE FOR ISOLATED STRONG UPDRAFT FORMATION
POSSIBLY LEADING TO A FEW SEVERE T-STORMS IN THE VICINITY OF THE
CONVERGENCE ZONE. HAIL AND STG WINDS MAIN THREATS...BUT CAN NOT
RULE OUT A WEAK TORNADO OR TWO. LATEST DAY-3 OUTLOOK FROM SPC HAS
THIS AREA UNDER A MARGINAL RISK. AT THIS TIME...APPEARS MOST OF
THIS STORM ACTIVITY WILL DIE OFF DURING THE EVENING...ONLY TO
CHANGE OVER TO AREAS OF LIGHT RAIN SHOWERS OVERNIGHT AS THE LIFT
PRODUCED BY THE PASSING UPPER TROUGH CONTINUES.
ON SATURDAY...MODELS SHOW THE UPPER TROUGH OPENING UP AS IT SWINGS
NEWRD OVER WYOMING AND THE NORTHERN GREAT PLAINS BY LATE IN THE
DAY. STILL SUFFICIENT MOISTURE...LIFT AND INSTABILITY AROUND TO
PRODUCE PLENTY OF CLOUD COVER AS WELL AS A CHANCE OF SHOWERS AND
ISOLATED LATE DAY T-STORMS. STRONG COOLING ALOFT AND CLOUD COVER
WILL GIVE US MUCH COOLER TEMPERATURES ON SATURDAY. GFS TEMPS
CONTINUE TO RUN COOLEST OF THE MODELS AS IT INDICATES HIGHS ONLY
THE 50S AT LOWER ELEVATIONS. WHEREAS NAM AND ECMWF TEMPS CONTINUE
TO RUN WARMER...IN SOME AREAS SEVERAL DEGREES WARMER. DECIDED TO
USE A BLEND OF THESE MODELS AND GO WITH LOWER 60S ON THE PLAINS
AND 50S IN THE HIGH COUNTRY. OH YES...ELEVATIONS ABOVE AROUND 10K
FT WILL CERTAINLY BE COLD ENOUGH FOR SNOW OR A RAIN/SNOW MIX
FRIDAY NIGHT/EARLY SATURDAY WITH MINOR ACCUMULATIONS POSSIBLE.
SUNDAY INTO MONDAY...THE UPPER TROUGH EXITS THE REGION ALLOWING FOR
A SHORTWAVE RIDGE TO BUILD OVER THE REGION. SWLY FLOW ALOFT WILL
AID IN RETURNING TEMPS TO NEAR OR SLIGHTLY ABOVE AVERAGE BY MONDAY.
THERE/S STILL A SLIGHT CHANCE OF AFTERNOON SHOWERS/T-STORMS MAINLY
IN THE HIGH COUNTRY BOTH DAYS. BY TUESDAY...MEDIUM RANGE MODELS
DIFFER QUITE A BIT AS THE GFS SHOWS YET ANOTHER DEEP UPPER TROUGH
TAKING AIM ON COLORADO. WHILE THE ECMWF SHOWS THIS TROUGH WASHING
OUT AND RACING EAST ACRS COLORADO AS AN OPEN WAVE DURING THE DAY
TUESDAY. WILL NOT TRY TO FIGURE ALL THIS OUT AND STICK WITH CLIMO
FOR NOW.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z THURSDAY MORNING)
ISSUED AT 938 AM MDT WED SEP 30 2015
VFR CONDITIONS WILL PERSIST THROUGH THURSDAY. ONLY ISOLATED HIGH
BASED SHOWER POSSIBLE 22Z-03Z. LIGHT EASTERLY WIND COMPONENT
EXPECTED MOST OF THE DAY WITH NORMAL DRAINAGE WINDS OVERNIGHT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BARJENBRUCH
SHORT TERM...GIMMESTAD
LONG TERM...BAKER
AVIATION...BARJENBRUCH
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
444 AM MDT WED SEP 30 2015
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 443 AM MDT WED SEP 30 2015
BAND OF MID/HIGH CLOUDINESS ASSOCIATED WITH THE JET WILL SHIFT
SLOWLY EASTWARD TODAY. AT THE SURFACE THERE IS A WEAK DENVER
CYCLONE...ACTUALLY MORE OF A SHEAR ZONE BETWEEN THE SOUTHEAST
WINDS ON THE PLAINS AND VERY LIGHT NORTH WINDS NEAR THE MOUNTAINS.
THIS FEATURE WILL LIKELY PERSIST THROUGH THE DAY...AND WILL
PROBABLY PROGRESS EASTWARD A BIT WITH TIME. THERE IS WIDESPREAD
STRATUS AND AREAS OF FOG EAST OF THIS BOUNDARY...WITH PATCHY FOG
JUST STARTING TO DEVELOP FURTHER WEST HINDERED BY THE HIGH
CLOUDS. THIS WILL EVENTUALLY SET UP A DECENT TEMPERATURE GRADIENT
WITH THE COOLER MOIST AIR OUT EAST...AND A LITTLE MIXING WITH
WARMER AND SLIGHTLY DRIER AIR AROUND DENVER. WITH MARGINAL
TEMPERATURES AND LITTLE CAPE OVER THE WESTERN PART OF THE
AREA...AND COOL TEMPERATURES IN THE EAST...EXPECT THAT SHOWERS
TODAY WILL BE DRIVEN BY THE JET. PROBLEM IS THE LACK OF MID LEVEL
MOISTURE WHICH MAY LIMIT THE ACTIVITY. HRRR SHOWS A NARROW BAND OF
WEAK CONVECTION OVER THE MOUNTAINS AT MIDDAY SHIFTING EAST INTO
THE PALMER DIVIDE AREA THIS AFTERNOON. BUT THE HRRR TENDS TO
OVERDO WEAK CONVECTION LIKE THIS. SHOULD BE CLOSE ENOUGH TO
INSTABILITY TO GET SOME SHOWERS OR STORMS OVER THE MOUNTAINS WITH
THE HELP OF SOME LIFT...LESS SURE ABOUT HOW MUCH WOULD MAKE IT
ONTO THE PLAINS. ONLY MINOR CHANGES TO THE EXISTING LOW POPS
MAINLY OVER THE MOUNTAINS...AND PALMER DIVIDE LATE IN THE DAY.
AS FOR TEMPERATURES...TRIMMED A COUPLE DEGREES OFF THE EASTERN
BORDER AREAS...OTHERWISE THEY LOOK GOOD. NEAR GUIDANCE TODAY AND A
LITTLE WARMER TONIGHT AS THERE WILL STILL BE LOTS OF CLOUD COVER.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 443 AM MDT WED SEP 30 2015
BIG DIFFERENCES IN THE MODELS PARTICULARLY WITH REGARD TO THE
POSITION/FORWARD PROGRESS OF THE BIG UPPER TROUGH DURING THE
FRI/SAT TIME FRAME. MODELS START OUT IN GOOD AGREEMENT BY SHIFTING
THE TALL UPPER RIDGE OVER COLORADO ON THURSDAY EAST OF THE STATE
BY FRIDAY MORNING. WARM SWLY/DOWNSLOPE FLOW AND PLENTY OF SUNSHINE
TO START THE DAY WILL HAVE LITTLE TROUBLE PUSHING TEMPS INTO THE
LOWER 80S ALONG THE FRONT RANGE BY AFTERNOON. NOT SO FARTHER EAST
ON THE PLAINS WHERE AREAS OF STRATUS AND FOG WILL LIKELY DELAY
WARMING UNTIL AFTERNOON RESULTING IN MAX TEMPS ONLY IN THE LOW/MID
70S OUT THERE. THE FOG ACRS LINCOLN...ERN ELBERT AND SRN PORTIONS
OF WASHINGTON COUNTIES EARLY THURSDAY COULD BE RATHER THICK AS
THIS AREA WILL BE SUBJECTED TO MOIST SELY BOUNDARY LAYER FLOW ALL
NIGHT. MEANWHILE DAYTIME HEATING COUPLED WITH MODEST MID-LEVEL
DESTABILIZATION COULD PRODUCE A FEW SHOWERS/T-SHOWERS OVER HIGHER
ELEVATIONS OF THE FRONT RANGE. THEN DURING THE EVENING HOURS...
CONTINUED ADVECTION OF LOW-LEVEL MOISTURE ON GUSTY SELY WINDS MAY
COMBINE WITH WEAK SHEAR/INSTABILITY ALONG A STALLED OUT SFC TROUGH
TO SPAWN A FEW WEAK T-STORMS ACROSS THE NERN CORNER OF THE STATE.
BUT WITH MINIMAL CAPE ANY STORMS THAT FORM WILL BE OF LITTLE
CONSEQUENCE.
ON FRIDAY..MODEL CONSENSUS SHOWS THE UPPER TROUGH TO OUR WEST
CLOSING OFF OVER NORTHERN UTAH AND MID-LEVEL SWLY FLOW OVER
COLORADO STRENGTHENING. MEANWHILE PRESSURE/HEIGHT FALLS ACRS
WYOMING IN THE PATH OF THE UPPER LOW AID IN STRENGTHENING THE SELY
LOW-LEVEL FLOW IN EASTERN COLORADO DURING THE DAY. MOISTURE
CONTINUES TO ADVECT UP INTO THE AREA RESULTING IN INCREASING CLOUD
COVER OVER THE MTNS FIRST...THEN OVER THE EASTERN SECTIONS OF THE
CWA THROUGH THE AFTERNOON. CLOSE IN TO THE FRONT RANGE SWLY/
DOWNSLOPE FLOW DURING THE MORNING WILL ALLOW SOLAR HEATING TO
PUSH TEMPS INTO THE LOWER 70S BY MIDDAY. THEN MODELS PARTICULARLY
THE NAM SHOW A DENVER CYCLONE FORMING NEAR DIA WITH STRENGTHENING
SELY WINDS ON THE PLAINS BY EARLY AFTERNOON. NOT LONG AFTER ITS
FORMATION MODELS SHOW A SHARP DENVER VORTICITY CONVERGENCE ZONE
SETTING UP EAST-SOUTHEAST OF DENVER...WITH THE NAM INDICATING SFC
BASED CAPES APPROACHING 2000 J/KG BY LATE AFTERNOON. SELY SFC
FLOW TOPPED BY STRENGTHENING SWLY FLOW ALOFT WILL PROVIDE A
FAVORABLE SHEAR PROFILE FOR ISOLATED STRONG UPDRAFT FORMATION
POSSIBLY LEADING TO A FEW SEVERE T-STORMS IN THE VICINITY OF THE
CONVERGENCE ZONE. HAIL AND STG WINDS MAIN THREATS...BUT CAN NOT
RULE OUT A WEAK TORNADO OR TWO. LATEST DAY-3 OUTLOOK FROM SPC HAS
THIS AREA UNDER A MARGINAL RISK. AT THIS TIME...APPEARS MOST OF
THIS STORM ACTIVITY WILL DIE OFF DURING THE EVENING...ONLY TO
CHANGE OVER TO AREAS OF LIGHT RAIN SHOWERS OVERNIGHT AS THE LIFT
PRODUCED BY THE PASSING UPPER TROUGH CONTINUES.
ON SATURDAY...MODELS SHOW THE UPPER TROUGH OPENING UP AS IT SWINGS
NEWRD OVER WYOMING AND THE NORTHERN GREAT PLAINS BY LATE IN THE
DAY. STILL SUFFICIENT MOISTURE...LIFT AND INSTABILITY AROUND TO
PRODUCE PLENTY OF CLOUD COVER AS WELL AS A CHANCE OF SHOWERS AND
ISOLATED LATE DAY T-STORMS. STRONG COOLING ALOFT AND CLOUD COVER
WILL GIVE US MUCH COOLER TEMPERATURES ON SATURDAY. GFS TEMPS
CONTINUE TO RUN COOLEST OF THE MODELS AS IT INDICATES HIGHS ONLY
THE 50S AT LOWER ELEVATIONS. WHEREAS NAM AND ECMWF TEMPS CONTINUE
TO RUN WARMER...IN SOME AREAS SEVERAL DEGREES WARMER. DECIDED TO
USE A BLEND OF THESE MODELS AND GO WITH LOWER 60S ON THE PLAINS
AND 50S IN THE HIGH COUNTRY. OH YES...ELEVATIONS ABOVE AROUND 10K
FT WILL CERTAINLY BE COLD ENOUGH FOR SNOW OR A RAIN/SNOW MIX
FRIDAY NIGHT/EARLY SATURDAY WITH MINOR ACCUMULATIONS POSSIBLE.
SUNDAY INTO MONDAY...THE UPPER TROUGH EXITS THE REGION ALLOWING FOR
A SHORTWAVE RIDGE TO BUILD OVER THE REGION. SWLY FLOW ALOFT WILL
AID IN RETURNING TEMPS TO NEAR OR SLIGHTLY ABOVE AVERAGE BY MONDAY.
THERE/S STILL A SLIGHT CHANCE OF AFTERNOON SHOWERS/T-STORMS MAINLY
IN THE HIGH COUNTRY BOTH DAYS. BY TUESDAY...MEDIUM RANGE MODELS
DIFFER QUITE A BIT AS THE GFS SHOWS YET ANOTHER DEEP UPPER TROUGH
TAKING AIM ON COLORADO. WHILE THE ECMWF SHOWS THIS TROUGH WASHING
OUT AND RACING EAST ACRS COLORADO AS AN OPEN WAVE DURING THE DAY
TUESDAY. WILL NOT TRY TO FIGURE ALL THIS OUT AND STICK WITH CLIMO
FOR NOW.
&&
.AVIATION...(FOR THE TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 443 AM MDT WED SEP 30 2015
PATCHES OF FOG AND LOW CLOUDS ARE JUST STARTING TO DEVELOP FROM
DENVER NORTHWARD...THERE IS A SLIGHT CHANCE OF HAVING IFR
CEILINGS/VISIBILITIES FOR A COUPLE OF HOURS AT KDEN/KBJC BETWEEN
NOW AND 15Z. MORE LIKELY THE FOG WILL NOT BE A FACTOR. OTHERWISE
VFR CONDITIONS ARE EXPECTED THROUGH TONIGHT WITH ONLY ISOLATED
SHOWER ACTIVITY THIS AFTERNOON.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GIMMESTAD
LONG TERM...BAKER
AVIATION...GIMMESTAD
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
629 AM CDT WED SEP 30 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 307 AM CDT WED SEP 30 2015
TODAY AND TONIGHT...SPRINKLES SHOULD EXIT THE FCST AREA BY OR AROUND
15Z ACCORDING TO THE RAP MODEL. SOUTH WINDS KEEP MOISTURE IN PLACE
ACROSS WRN NEB TODAY AND TONIGHT WITH MIXING PROCESSES PRODUCING
PARTLY CLOUDY SKIES. STRATUS SHOULD RETURN TONIGHT ACCORDING TO THE
SREF MODEL.
HIGHS IN THE 60S ARE IN PLACE TODAY WITH COOL AIR RECYCLING
NORTHWARD. LOWS IN THE 50S FOLLOW TONIGHT WITH THE EXPECTED CLOUD
COVER.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 307 AM CDT WED SEP 30 2015
AN UPPER LEVEL BLOCKING PATTERN EXPECTED TO PERSIST THROUGH THE
WEEKEND INTO EARLY NEXT WEEK. THIS WILL CONSIST OF A LONG WAVE
TROUGH ACROSS THE WESTERN CONUS...AN UPPER RIDGE ACROSS THE GREAT
LAKES AND EASTERN CANADA...AND A CUT OFF UPPER LEVEL LOW ACROSS
THE SOUTHEAST CONUS. EXPECT A SYSTEM TO EJECT EAST FROM THE
WESTERN CONUS LONG WAVE TROUGH INTO THE CENTRAL AND NORTHERN
PLAINS FRIDAY INTO SATURDAY...WITH THE ENTIRE LONG WAVE TROUGH TO
TRANSLATE EAST INTO THE CENTRAL AND NORTHERN PLAINS EARLY NEXT
WEEK AS THE UPPER PATTERN FINALLY BECOMES A BIT MORE PROGRESSIVE.
AS MENTIONED A SHORTWAVE TROUGH WILL EJECT EAST INTO THE REGION
FRIDAY INTO SATURDAY...THEN WEAKEN AND DISSIPATE SUNDAY AS IT
ENCOUNTERS THE STRONG UPPER LEVEL RIDGING ANCHORED ACROSS THE
GREAT LAKES/EASTERN CANADA. MODELS CONTINUE TO TREND SLOWER WITH
THIS SYSTEM...AND HAVE DELAYED THE ONSET OF RAIN UNTIL THURSDAY
NIGHT ACROSS NORTHWEST NEBRASKA. EXPECT RAIN TO SPREAD EAST
FRIDAY...WITH THE HEAVIEST MOST CONCENTRATED PERIOD OF RAIN TO
FALL FRIDAY NIGHT. DRY AIR IN THE LOWER LEVELS OF THE ATMOSPHERE
WILL BE CIRCULATING INTO EASTERN AND CENTRAL NEBRASKA OFF THE HIGH
ACROSS THE GREAT LAKES AND EASTERN CANADA. THIS WILL DELAY THE
RAIN UNTIL POSSIBLY FRIDAY NIGHT FOR AREAS AROUND
ONEILL...BARTLETT AND EWING.
THIS DRY AIR MAKES FOR A DIFFICULT FORECAST IN REGARDS TO STRATUS
CLOUD COVER. IT APPEARS THAT ENOUGH OF THE DRY AIR WILL MIX INTO
WESTERN NEBRASKA...AND HELP TO THIN AND BREAK UP THE STRATUS CLOUD
DECK THURSDAY AFTERNOON. FARTHER EAST...LITTLE IN THE WAY OF
STRATUS CLOUD COVER IS EXPECTED ACROSS CENTRAL AND NORTH CENTRAL
NEBRASKA WHERE THE DRY AIR LAYER WILL BE DEEPER. WITH THE ARRIVAL
OF THE SHORTWAVE TROUGH FRIDAY...MIDDLE AND HIGH CLOUDS WILL
DEVELOP AND OVERSPREAD THE AREA. IN ADDITION...THE LOW LEVELS WILL
REMAIN MOIST ENOUGH THAT A LOW CLOUD STRATUS DECK SHOULD REMAIN IN
PLACE THROUGH THE DAY ACROSS FAR WESTERN NEBRASKA AND THE
PANHANDLE. STILL EXPECTING THE DRIER AIR TO KEEP STRATUS TO A
MINIMUM FARTHER EAST. BY FRIDAY NIGHT INTO SATURDAY...ALL AREAS
WILL SEE THE LOWER LEVELS MOISTEN WITH A SOLID OVERCAST.
FOR THURSDAY AND FRIDAY...EXPECT THE COOLER HIGH TEMPERATURES TO
RESIDE ALONG AND WEST OF HIGHWAY 83 WHERE MORE CLOUD COVER IS
EXPECTED. THEN ON SATURDAY EXPECT A RAW DAY ACROSS ALL OF THE
AREA...WITH HIGHS BARELY REACHING INTO THE 50S DUE TO CLOUDS AND
COOL EAST/SOUTHEAST LOW LEVEL FLOW.
EARLY NEXT WEEK THE LONG WAVE TROUGH MIGRATES EAST BUT DAMPENS AS IT
MOVES INTO THE CENTRAL AND NORTHERN PLAINS. FOR NOW AT LEAST A LOW
CHANCE POP FOR SHOWERS SEEMS WARRANTED WITH THE ARRIVAL OF THE
TROUGH.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 629 AM CDT WED SEP 30 2015
THE AREA OF MVFR/IFR CIGS SHOULD MIX OUT TO MVFR/VFR A BIT LATER
THIS MORNING...16Z-18Z. THESE LOW CIGS WILL LIKELY RETURN TONIGHT
ALONG AND WEST OF HIGHWAY 83 AS MVFR/IFR. OTHERWISE...VFR IS
EXPECTED TODAY AND TONIGHT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
611 AM CDT WED SEP 30 2015
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 313 AM CDT WED SEP 30 2015
LATEST WATER VAPOR IMAGERY AND RAP 500MB HEIGHT ANALYSIS SHOWS LARGE
RIDGE OF HIGH PRESSURE EXTENDING FROM NORTHWESTERN MEXICO INTO
BRITISH COLUMBIA/ALBERTA. DOWNSTREAM...A LARGE TROUGH EXTENDS FROM
HUDSON`S BAY TO EASTERN TEXAS PUTTING OUR REGION IN MODEST
NORTHWESTERLY FLOW. A WEAK SHORTWAVE OVER SOUTHEAST SOUTH DAKOTA HAS
PROVEN TO BE ENOUGH FORCING TO SPAWN A FEW RADAR RETURNS ACROSS
SOUTHEAST SOUTH DAKOTA AND NORTHEAST NEBRASKA. NOT ANTICIPATING
MUCH...IF ANYTHING...TO REACH THE GROUND AS OBS INDICATE ALL MID
CLOUDS. LOW LEVELS WILL REMAIN QUITE DRY WITH SFC HIGH PRESSURE
ANCHORED FROM QUEBEC SOUTHWESTWARD TO THE GREAT PLAINS.
THE ABOVE MENTIONED MID LEVEL SHORTWAVE WILL CONTINUE TO DROP
SOUTHEAST INTO MISSOURI EARLY TODAY. MID CLOUDS SHOULD DIMINISH
LATER THIS MORNING BUT HIGHS WILL REMAIN SLIGHTLY BELOW NORMAL IN
THE MID TO UPPER 60S.
THE UPPER RIDGE AXIS WILL SHIFT EAST TOWARD THE FORECAST AREA BY
THE WEEKEND AHEAD OF A LARGE APPROACHING UPPER TROUGH.
TEMPERATURES WILL REMAIN COOLER THAN NORMAL FOR THIS TIME OF THE
YEAR WITH CONTINUED EASTERLY LOW LEVEL FLOW.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 313 AM CDT WED SEP 30 2015
PCPN CHANCES BEGIN TO INCREASE ACROSS WESTERN AND CENTRAL NEBRASKA
FRIDAY NIGHT IN ADVANCE OF APPROACHING UPPER TROUGH. OVERALL
TREND HAS BEEN TO LOWER POPS IN OUR AREA AS BEST FORCING
ASSOCIATED WITH THE UPPER TROUGH REMAINS TO OUR WEST AND NORTH.
DRY AIR TO OUR EAST WILL BE PROBLEMATIC AND SHOULD KEEP CONDITIONS
MOSTLY DRY ACROSS THE EASTERN CWA.
THE BASE OF THE WESTERN UPPER TROUGH WILL ROUND THE FOUR CORNERS
REGION LATE IN THE EXTENDED. THIS COULD BRING PCPN TO THE AREA BY
EARLY TO MID NEXT WEEK HOWEVER MANY FORECAST UNCERTAINTIES
REMAIN.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 611 AM CDT WED SEP 30 2015
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...KERN
LONG TERM...KERN
AVIATION...BOUSTEAD
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
951 AM EDT WED SEP 30 2015
.SYNOPSIS...
A QUASI-STATIONARY FRONT EXTENDING FROM NORTHEAST TO SOUTHWEST
ACROSS SOUTH-CENTRAL VERMONT INTO CENTRAL NEW YORK WILL CONTINUE
TO PROVIDE A FOCUS FOR HEAVY RAINFALL THROUGH MID AFTERNOON
TODAY...AND WILL BRING THE PROSPECT OF MINOR TO MODERATE FLOODING
ON RIVERS AND STREAMS TODAY INTO THIS EVENING. A DEVELOPING WAVE
OF LOW PRESSURE ALONG THE FRONT WILL SHIFT EAST OF THE REGION LATE
THIS AFTERNOON...FINALLY ALLOWING THE FRONT TO PUSH SOUTH OF
VERMONT USHERING IN A DRIER AND COOLER AIR MASS FOR TONIGHT.
DESPITE SOME CONTINUED HIGH LEVEL CLOUDINESS...STRONG HIGH
PRESSURE ANCHORED ACROSS QUEBEC AND ONTARIO WILL BRING A PERIOD OF
DRY WEATHER THURSDAY THROUGH SATURDAY...WITH NEAR SEASONABLE
TEMPERATURES.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
AS OF 951 AM EDT WEDNESDAY...NO SIGNIFICANT CHANGES TO THE
FORECAST. FLOOD WATCH CONTINUES IN EFFECT THROUGH 06Z THURSDAY.
RIVERS ARE RISING AND WATCHING A FEW LIKE OTTER CREEK AT RUTLAND
AND MISSISQUOI AT NORTH TROY BUT AT THE MOMENT IT LOOKS LIKE WE
MIGHT DODGE ANY SIGNIFICANT FLOODING ON THE RIVERS.
FOR THE WEATHER...BLENDED IN SOME OF THE HRRR SIMULATED RADAR
TRENDS WHICH SHOWS DRY SLOT NOW MOVING TOWARD SOUTHERN VERMONT
WITH HEAVIEST BAND CENTRAL AND NORTHERN VT/NY THIS MORNING.
STILL EXPECTING UP TO ANOTHER INCH OF RAIN OR SO IN FROM BTV
SOUTH AND EAST WHERE RAIN WILL BE MAINLY MODERATE BUT LOCALLY
HEAVY FOR A FEW MORE HOURS.
RAIN WILL LIGHTEN UP AND MOVE OUT GRADUALLY THIS AFTERNOON THOUGH
THERE MAY STILL BE SOME VERY LIGHT RAIN OR DRIZZLE RIGHT UNTIL
SUNSET FOR NORTHEAST VERMONT AND THE MOUNTAINS.
LITTLE CHANGE IN TEMPS FOR THE REST OF THE DAY...A COOL ONE WITH
TEMPS MOSTLY IN THE 50S AND SOME UPPER 40S IN THE HIGHER TERRAIN
WITH FRESH NORTHERLY BREEZE.
HAVE RECENTLY RECEIVED OBSERVED STORM TOTAL RAINFALL REPORTS
AROUND 4-4.5" IN NORTH UNDERHILL...LINCOLN AND WATERVILLE VT. WE
WILL ISSUE A PUBLIC INFORMATION STATEMENT SHORTLY AFTER 10 AM
WITH MORE RAINFALL AMOUNTS.
PREVIOUS DISCUSSION FOLLOWS...
WIDESPREAD MODERATE TO HEAVY RAIN IN PLACE ACROSS ALL OF THE
NORTH COUNTRY EXCEPT ST. LAWRENCE VALLEY THIS MORNING...AND WILL
CONTINUE TO BE THE CASE THROUGH 18-20Z TODAY. SURFACE FRONTAL
BNDRY HAS BECOME QUASI- STATIONARY ACROSS SOUTH- CENTRAL VERMONT
AND THE SRN ADIRONDACKS AT 01Z...AND WILL CONTINUE TO PROVIDE A
FOCUS FOR THE HEAVIEST RAINFALL DURING THE NEXT 6-9 HRS. WE HAVE
SEVERAL DYNAMIC FEATURES IN PLAY THRU MID- AFTN. A STRENGTHENING
FRONTAL WAVE CONTINUES TO DEVELOP ACROSS WRN PA EARLY THIS
MORNING...AND WILL TRACK ENEWD ALONG THE FRONTAL ZONE REACHING
CENTRAL VT MID- LATE MORNING. THIS FEATURE ALSO STRENGTHENS WITHIN
RIGHT ENTRANCE REGION OF 250MB JET ACROSS ERN QUEBEC. WE ALSO
HAVE A SFC MESOLOW ACROSS NERN PA/NWRN NJ EMBEDDED IN TROPICAL
REGIME WITH LOW 70S DEWPOINTS AND PW VALUES IN EXCESS OF 2" (2.22"
OBSERVED AT 00Z WAL SOUNDING). HAVE SEEN RAINFALL RATES OF
0.50-0.60" PER HOUR WITH HIGHER REFLECTIVITY AREA STREAMING NWD
FROM NEW YORK CITY VCNTY. AS FRONTAL WAVE SHIFTS ENEWD...SURGE OF
45-55KT SOUTHERLY FLOW WILL ADVECT TROPICAL MOISTURE INTO THE
FRONTAL BNDRY ACROSS CENTRAL/S-CENTRAL VT DURING 12-18Z
PERIOD...WHICH CONTINUES CONCERN FOR FLOODING. ALSO NOTING STRONG
850-700MB FRONTOGENETIC FORCING 12-18Z...AND THIS MESOSCALE
CIRCULATION WILL AUGMENT SYNOPTIC ASCENT AND ENHANCE RAINFALL
RATES. COULD SEE AN ADDITIONAL 2-3" OF RAINFALL ACROSS
CENTRAL/S-CENTRAL VT...WITH CONTINUED PROSPECTS FOR MINOR TO
MODERATE FLOODING...ESPECIALLY ON SMALLER RIVERS AND STREAMS.
RUNOFF COULD CONTINUE TO RESULT IN RIVER RISES THRU THE FIRST HALF
OF TONIGHT. WE WILL CONTINUE TO CLOSELY MONITOR PRECIPITATION AND
HYDRO TRENDS THROUGHOUT THE DAY.
OTHERWISE...WILL SEE LOW-LEVEL CAA CONTINUE TO WORK IN FROM THE
NORTH AND WEST. CLOUDS/PRECIPITATION AND NORTH FLOW WILL KEEP TEMPS
IN THE 50S ACROSS MUCH OF THE NRN HALF OF THE FORECAST AREA...WHILE
READINGS STAY IN THE MID 60S ACROSS S-CENTRAL VT UNTIL FRONTAL WAVE
PASSES LATE THIS AFTN...AND FRONT SURGES SOUTHWARD AND OUT OF THE
REGION. IT APPEARS MOST OF THE RAIN SHOULD EXIT EASTERN VT BY 21Z OR
SO...AND WILL SHOW DECREASING POPS ACCORDINGLY FROM WEST TO EAST
DURING THE LATE AFTERNOON HRS. SOME CLEARING SHOULD WORK INTO NRN NY
TOWARD SUNSET...BUT UPPER CIRRUS CANOPY SHOULD REMAIN IN PLACE FOR
MOST SECTIONS HEADING THRU THIS EVENING.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH FRIDAY/...
AS OF 349 AM EDT WEDNESDAY...MUCH QUIETER STRETCH OF WEATHER
ANTICIPATED AS FRONTAL ZONE SHIFTS OFFSHORE SOUTHEAST OF NEW
ENGLAND AND STRONG SURFACE ANTICYCLONE ANCHORED ACROSS ONTARIO AND
QUEBEC BECOMES OUR CONTROLLING WEATHER FEATURE. HAVE SHOWN DRY
CONDITIONS THROUGHOUT. WINDS WILL CONTINUE MODERATELY STRONG FROM
THE NORTH DURING THE PERIOD (NORTH 15-20 MPH DURING THE DAYLIGHT
HRS THURSDAY) BRINGING COOLER TEMPERATURES WITH HIGHS IN THE MID-
UPR 50S FOR THURSDAY....AND GENERALLY MID 50S ON FRIDAY. MAY SEE
SOME PATCHY FROST THURSDAY NIGHT ACROSS SHELTERED SECTIONS OF NRN
NY...THOUGH CONTINUED SWLY UPR TROPOSPHERIC FLOW SHOULD MAINTAIN
SOME CIRRUS CLOUDS AND MITIGATE EXTENT OF RADIATIONAL COOLING.
ALSO COULD SEE WINDS CONTINUE ABOVE 5 MPH DURING THE NIGHTTIME
HRS...WHICH WOULD NOT BE CONDUCIVE FOR FROST FORMATION. HAVE LEFT
OUT OF THE OFFICIAL FORECAST FOR NOW. HAVE INDICATED LOW
TEMPERATURES UPR 30S TO LOW 40S TONIGHT AND AGAIN THURSDAY
NIGHT...BUT LOCALLY NEAR FREEZING IN THE COLDER SPOTS WITHIN THE
NRN ADIRONDACK REGION.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 349 AM EDT WEDNESDAY...SURFACE HIGH PRESSURE WILL KEEP
FRONTAL BOUNDARY JUST TO OUR SOUTH FRIDAY NIGHT THROUGH MOST OF
SATURDAY...BUT POPS WILL BE INCREASING AS THE HIGH BEGINS TO
WEAKEN LATE SATURDAY INTO EARLY SUNDAY. AS THIS IS
HAPPENING...TROPICAL CYCLONE JOAQUIN WILL MOVE NORTHWARD OFF THE
SOUTH CAROLINA COAST BY SATURDAY. MODEL GUIDANCE THEN DIVERGES
WITH REGARDS TO MID-UPPER LEVEL PATTERN AND TRACK/EVOLUTION OF
JOAQUIN. SEVERAL UPPER LEVEL CLOSED LOWS AND HIGH PRESSURE RIDGES
WILL GIVE THE MODELS DIFFICULTY IN RESOLVING TRACKS.
ECMWF CONTINUES TO KEEP JOAQUIN OFF THE COAST...WITH SLIGHT TREND
WEST WITH REGARDS TO TRACK. A MIDLEVEL SHORTWAVE COULD PRODUCE SOME
SHOWERS SUNDAY. OTHERWISE A MOSTLY DRY FORECAST BUT WITH JOAQUIN
TRACKING INTO A MIDLEVEL RIDGE HAVE OPTED TO LEAN TOWARDS THE GFS,
WHICH SHOWS JOAQUIN INTERACTING WITH CLOSED 500MB LOW OVER THE
SOUTHEASTERN STATES. THIS LOW WILL PULL JOAQUIN ONTO THE COAST
AROUND DELMARVA AND COMBINE WITH THE 500MB LOW... RESULTING IN
PRECIPITATION SPREADING ACROSS THE NORTH COUNTRY FROM THE SOUTH ON
SUNDAY ACCOMPANIED BY STRONG LOW LEVEL WINDS. THE LOW WILL BE SLOW
TO PROGRESS NORTHWARD PROVIDING SEVERAL DAYS OF POTENTIAL RAINFALL.
WILL HAVE TO MONITOR EVOLVING SYSTEMS AS MOISTURE FROM JOAQUIN AND
RESULTING RAINFALL COULD INCREASE THE POTENTIAL FOR MORE RIVER RISES
LATE IN THE WEEKEND. SINCE THERE ARE STILL SOME TIMING ISSUES...HAVE
LEFT PRECIPITATION CHANCES IN THE EXTENDED GENERALLY IN THE CHANCE
CATEGORY. BELOW NORMAL TEMPERATURES WILL TREND WARMER TO NEAR
SEASONAL NORMALS BY EARLY NEXT WEEK.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
THROUGH 12Z THURSDAY...RAIN CONTINUES TO PRODUCE FLIGHT
CONDITIONS VARYING BETWEEN MVFR AND IFR. AN AREA OF HEAVIER
SHOWERS EXPECTED TO MOVE IN FROM THE SOUTH AND PRODUCE IFR/LIFR
CONDITIONS MAINLY BETWEEN 12Z- 16Z. GUSTY WINDS WILL PICK UP FROM
THE NORTH AT 10-20KTS WITH GUSTS UP TO 25KTS EXPECTED.
RAIN WILL EXIT FROM WEST TO EAST LATE THIS MORNING/EARLY THIS
AFTERNOON AND RESULT IN MVFR CONDITIONS, WITH BOUTS OF IFR
POSSIBLE, IMPROVING TO VFR IN THE MID MORNING...WITH PRECIP ENDING
IN THE AFTERNOON.
HEADING INTO THE EVENING...WINDS WILL CONTINUE OUT OF THE NORTH
AT 5-10KTS AND SHOULD INHIBIT FOG DEVELOPMENT.
OUTLOOK 12Z THURSDAY THROUGH SATURDAY...
12Z THURSDAY THROUGH 00Z SATURDAY...PRIMARILY DRY AND VFR WITH
BRIEF WINDOW OF HIGH PRESSURE.
00Z SATURDAY ONWARD...INCREASING CHANCES FOR RAIN WITH REDUCTIONS
TO MVFR POSSIBLE WITH LOW PRESSURE SYSTEM.
&&
.MARINE...
AS OF 355 AM EDT WEDNESDAY...A LAKE WIND ADVISORY CONTINUES IN
EFFECT UNTIL FURTHER NOTICE FOR LAKE CHAMPLAIN. THE COLD FRONT HAS
PUSHED SOUTH OF LAKE CHAMPLAIN...AND WILL CONTINUE TO SEE NORTH
WINDS 18-25 KTS THIS MORNING...INCREASING TO 20-30 KTS THIS
AFTERNOON AND EVENING. LAKE WIND ADVISORY CRITERIA WILL LIKELY BE
MET THROUGH THURSDAY...WITH WINDS REMAINING FROM THE NORTH. WAVES
WILL GENERALLY BE IN THE 2 TO 4 FT RANGE, PARTICULARLY HIGHEST IN
BAYS AND INLETS ON THE SOUTHERN END OF LAKE CHAMPLAIN. WAVES MAY
BRIEFLY REACH 3 TO 5 FT TONIGHT.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...FLOOD WATCH THROUGH LATE TONIGHT FOR VTZ007>012-018-019.
NY...FLOOD WATCH THROUGH LATE TONIGHT FOR NYZ034-035.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS/SISSON
SHORT TERM...BANACOS
LONG TERM...KGM
AVIATION...KGM
MARINE...LOCONTO
AREA FORECAST DISCUSSION
NWS BISMARCK ND
906 AM CDT WED SEP 30 2015
.UPDATE...
ISSUED AT 901 AM CDT WED SEP 30 2015
CUT DOWN ON CLOUD COVER JUST A LITTLE BIT BASED ON LATEST
SATELLITE IMAGERY AND HIGH RESOLUTION MODEL TRENDS. DECIDED TO
BUMP UP WINDS SLIGHTLY LATER THIS AFTERNOON IN THE EAST BASED ON
RAP BUFKIT SOUNDINGS AT KJMS. ALSO DELAYED ONSET OF ISOLATED
PRECIPITATION CHANCES UNTIL 21Z IN THE NORTH CENTRAL AND NORTHEAST
BASED ON LATEST RAP AND NAM RUNS. OTHER THAN THAT...FORECAST LOOKS
ON TRACK AND NO OTHER MAJOR UPDATES WERE NEEDED.
UPDATE ISSUED AT 626 AM CDT WED SEP 30 2015
HIGH PRESSURE OVER THE NORTHERN GREAT LAKES REGION...AND LOW
PRESSURE OVER EASTERN MONTANA IS PRODUCING A MODERATE SOUTHERLY
FLOW ACROSS WESTERN AND CENTRAL NORTH DAKOTA THIS MORNING.
TEMPERATURES REMAIN MAINLY IN THE UPPER 40S TO MIDDLE 50S AND HAVE
NOT DROPPED AS LOW AS FORECAST. SOME AREAS COULD DROP A COUPLE
MORE DEGREES BUT IN GENERAL THINK WE HAVE SEEN OVERNIGHT LOWS.
WILL ADJUST TEMPERATURES TO REFLECT THIS. MADE SOME CHANGES TO SKY
COVER BASED ON LATEST SATELLITE IMAGERY. A FEW SHOWERS SHOWING UP
ON RADAR OVER THE JAMES RIVER VALLEY TRACKING NORTHEAST. ADDED A
SLIGHT CHANCE OF AN EARLY MORNING SHOWER HERE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 322 AM CDT WED SEP 30 2015
CURRENTLY...A LARGE SURFACE HIGH WAS CENTERED OVER THE GREAT LAKES
AREA...WITH A LOW PRESSURE TROUGH IN THE LEE OF THE ROCKIES. AT
UPPER LEVELS...A LARGE LOW OVER HUDSON BAY AND A RIDGE OVER THE
ROCKIES RESULTED IN SLIGHT NORTHWEST FLOW ALOFT OVER NORTH DAKOTA.
AN UPPER LEVEL SHORTWAVE WAS NOTED OVER SOUTH CENTRAL SASKATCHEWAN
IN THE LATEST SATELLITE WATER VAPOR LOOP.
SURFACE WINDS ACROSS THE REGION WERE SOUTHERLY...WITH SOUTHERLY
WINDS AT H925 AT 30 KNOTS OVER CENTRAL AND EASTERN NORTH DAKOTA.
THIS LOW LEVEL JET EXTENDS WELL NORTHWARD INTO MANITOBA. IT IS
LIKELY ASSOCIATED WITH A SHOWER THAT DEVELOPED NEAR THE TURTLE
MOUNTAINS...AND HAS SINCE MOVED NORTHEASTWARD INTO MANITOBA. THIS
INDICATES INSTABILITY IS GREAT ENOUGH FOR SHOWERS. THIS LOW LEVEL
JET IS FORECAST TO REMAIN OVER THE DAKOTAS TODAY AND
TONIGHT...HELPING TO KEEP LOW AND MID-LEVEL MOISTURE MOVING
NORTHWARD FROM THE CENTRAL PLAINS. MEANWHILE THE AFOREMENTIONED
SHORTWAVE OVER SOUTHERN SASKATCHEWAN IS PROGGED TO REACH THE
SOUTHERN BORDER OF SASK/MAN THIS AFTERNOON...THEN STALL THERE
TONIGHT. THE INCREASING CLOUDS/MOISTURE AND SUPPORT FROM THE UPPER
LEVEL SHORTWAVE SHOULD PROVIDE ENOUGH INSTABILITY FOR SHOWERS THIS
MORNING...AND THUNDERSTORMS THIS AFTERNOON AND TONIGHT. BEST CHANCES
THIS AFTERNOON LOOK TO BE OVER NORTH CENTRAL NORTH DAKOTA. THE PUSH
OF DRY AIR FROM THE WEST...ON THE WEST SIDE OF THE LOW LEVEL
JET...THIS AFTERNOON AND TONIGHT WILL EXPAND THE AREA OF POTENTIAL
SHOWERS/THUNDER OVER MUCH OF WESTERN AND CENTRAL NORTH DAKOTA
TONIGHT AND CHANCES OF PRECIPITATION INCREASE. GIVEN FAIRLY LOW
BOUNDARY LAYER CAPE OF 250-500 J/KG MOST AREA...WILL OPT FOR CHANCES
OF SHOWERS BUT WITH ONLY ISOLATED THUNDERSTORMS EMBEDDED IN THE
SHOWERS.
WITH DAYTIME HEATING THE SURFACE LAYER SHOULD LINK WITH THE LOW
LEVEL JET...AND BRING WINDY CONDITIONS TO CENTRAL NORTH DAKOTA.
LOOKING AT 20 TO 25 MPH SUSTAINED WINDS WITH GUSTS TO AROUND 30 MPH.
HIGHS TODAY SHOULD RANGE FROM THE UPPER 60S OVER THE JAMES RIVER
BASIN...TO THE UPPER 70S SOUTHWEST. LOWS TONIGHT IN THE 40S.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 322 AM CDT WED SEP 30 2015
A COMPLEX UPPER LEVEL PATTERN HIGHLIGHTS THE LONG TERM PERIOD OVER
THE UPCOMING WEEKEND.
ON THURSDAY...A SHORTWAVE TROUGH CURRENTLY TRACKING THROUGH
SASKATCHEWAN RETROGRADES WESTWARD FROM MANITOBA BACK INTO
SASKATCHEWAN AS A REX BLOCK DEVELOPS WITH THE BLOCKING HIGH OVER
NORTHERN SASKATCHEWAN AND MANITOBA...AND THE UPPER LOW DEVELOPING
FROM THE AFOREMENTIONED SHORTWAVE. THE UPPER LOW EVENTUALLY GETS
PULLED NORTHWARD...OUT OF THE REGION...BUT THERE SHOULD BE ENOUGH
INSTABILITY ASSOCIATED WITH THE UPPER LOW TO PRODUCE SCATTERED
SHOWERS MAINLY ACROSS CENTRAL NORTH DAKOTA ON THURSDAY.
THURSDAY NIGHT THROUGH SATURDAY...THERE COULD BE A FEW REMAINING
SHOWERS INTO THURSDAY EVENING ASSOCIATED WITH THE CANADIAN LOW...BUT
BY THIS TIME THE FOCUS SHIFTS WESTWARD AS ANOTHER UPPER LOW TRACKS
ACROSS THE NORTHERN AND CENTRAL ROCKIES. THE LOW BECOMES NEARLY
STATIONARY OVER THE NORTHERN ROCKIES AND NORTHERN HIGH PLAINS AS
ANOTHER UPPER LOW DIGS SOUTH ALONG THE WEST COAST. SHORTWAVE
ENERGY LIFTING THROUGH THE BROAD UPPER CIRCULATION IN COMBINATION
WITH AN INCREASING WARM ADVECTION PATTERN OVER THE WESTERN DAKOTAS
WILL RESULT IN A BROADER....MORE EXPANSIVE AREA OF SHOWERS FRIDAY
THROUGH SATURDAY. THE RESULT WILL BE FOR LIKELY POPS WEST AND A
CHANCE IN CENTRAL NORTH DAKOTA FRIDAY/FRIDAY NIGHT...AND HIGH
CHANCE POPS REMAINING OVER THE WEST SATURDAY. THE SHOWERS
GRADUALLY DWINDLE SATURDAY NIGHT INTO SUNDAY.
SIGNIFICANT EC/GFS MODEL DIFFERENCES DEVELOP BEYOND SUNDAY IN THE
HANDLING OF THE SECOND WEST COAST UPPER LOW. AND THE AMOUNT OF
INTERACTION BETWEEN THIS LOW AND THE NORTHERN STREAM JET.
VERY COOL TEMPERATURES FRIDAY THROUGH SUNDAY WITH SIGNIFICANT
CLOUD COVER AND SHOWERS. HIGHS FORECAST IN THE MID TO UPPER 50S
TO LOWER 60S ACROSS WESTERN AND CENTRAL NORTH DAKOTA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 626 AM CDT WED SEP 30 2015
SCATTERED TO OCCASIONALLY BROKEN CLOUDS BETWEEN 3500 AND 6000 FEET
ARE EXPECTED TO PERSIST TODAY OVER CENTRAL NORTH DAKOTA AFFECTING
THE KBIS/KMOT/KJMS TAFS. FARTHER WEST SOME MVFR CIGS WERE NOTED AT
KHEI AND EXPECTED TO MOVE NORTH INTO KDIK. KEPT A SCT DECK AT
KDIK AND KISN FOR NOW.
THE MODELS BRING IN AN UPPER LEVEL LOW TO SOUTHERN SASK/MAN
AND INTO NORTHERN ND THIS AFTERNOON. DID NOT MENTION SHOWERS OR
POSSIBLE THUNDER FOR THE AFTERNOON DUE TO EXPECTED ISOLATED NATURE
OF SHOWERS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ZH
SHORT TERM...JV
LONG TERM...TWH
AVIATION...TWH/JV
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1040 AM EDT WED SEP 30 2015
.SYNOPSIS...
AN AREA OF LOW PRESSURE WILL INTO NEW ENGLAND TODAY FOLLOWED BY A
WEAK RIDGE OF HIGH PRESSURE. ANOTHER SIGNIFICANT RAIN EVENT IS
POSSIBLE FRIDAY INTO THE UPCOMING WEEKEND AS A DEEPENING UPPER LOW
OVER THE SOUTHERN APPALACHIANS DRAWS MOISTURE INLAND FROM THE
WESTERN ATLANTIC.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MESO ANAL AS OF 10 AM HAS THE SURFACE LOW NEAR SPRINGFIELD MASS
ON A TRACK OFF TOWARD THE GULF OF MAINE. NORTHERLY FLOW IN ITS
WAKE WILL BRING A PERIOD OF DRYING CONDITIONS TO THE REGION WITH
THE HRRR SUPPORTING THE IDEA OF THE LAST OF THE STEADY RAIN
TAPERING TO JUST SCATTERED SHOWERS THIS AFTERNOON.
TIGHTENING SFC PRESSURE GRADIENT DEVELOPING EAST ACROSS THE STATE
TODAY WILL CREATE A GUSTY NORTHERLY WIND. WINDS WILL AVERAGE
10-15 MPH WITH GUSTS INTO THE LOW/MID 20S THIS AFTERNOON AND
EVENING.
TEMPS IN THE U50S NORTH...AND UPPER 60S ACROSS THE SOUTHERN HALF
OF THE STATE WILL BE NEARLY STEADY OR SLOWLY FALLING THIS
AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
THIS PERIOD WILL FEATURE PARTLY TO MOSTLY CLOUDY...BREEZY AND
COOLER CONDITIONS WITH JUST A CHANCE OF SOME SHOWERS AND SOUTHERN
TIER OF PENN BEGINNING THURSDAY AFTERNOON.
LOW TEMPS TONIGHT WILL RANGE FROM THE LOWER 40S ACROSS THE NW
MTNS...TO THE LOWER 50S THROUGHOUT THE LOWER SUSQ VALLEY.
HIGHS THURSDAY WILL BE MAINLY IN THE UPPER 50S...TO AROUND 60S IN
THE CENTRAL AND SOUTHERN VALLEYS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
STALLED OUT FRONT JUST OFFSHORE OF THE MID ATL COAST WILL SEE
MOISTURE BEGIN TO BE LIFTED OVER IT AND PULLED NWWD AS AN UPPER
LOW DEVELOPS SE OVER THE SOUTHERN APPALACHIANS. RAIN SHOULD
GRADUALLY EXPAND ACROSS THE SOUTHEAST PIEDMONT THURSDAY NIGHT AND
FRIDAY...THEN BEGIN TO DRIFT SLOWLY NWWD TWD CENTRAL PENN FRIDAY
INTO SATURDAY.
EVEN IF SOON TO BE HURRICANE JOAQUIN TAKES A TRACK OFFSHORE OF THE
MID ATL REGION PER THE EC AND LATEST TPC GUIDANCE...THE UPPER LOW
AND BACKING MID AND UPPER FLOW /WITH A HIGHLY ANOMALOUS -4 TO -5
SIGMA EASTERLY LLVL WIND AND AXIS OF HIGHER PWAT AIR/ WILL
TRANSPORT PULSE OF RAIN INLAND FROM THE ATLANTIC...UP AND OVER THE
VERY CHILLY AIRMASS ACROSS PENN. TEMPS SATURDAY...MAY STRUGGLE TO
CLIMB INTO THE LOWER 50S ACROSS THE CENTRAL AND NW MTNS...WHILE
THE SUSQ VALLEY COULD EDGE INTO THE UPPER 50S. THESE MAX TEMPS
WILL BE AT LEAST 10 DEG F BELOW NORMAL...AND POSSIBLY UP TO 15 DEG
IN SOME AREAS.
RIGHT NOW WE HAVE MDT AMOUNTS OF AROUND ONE INCH OF RAIN
FCST HEADING INTO THIS WEEKEND...AND THE LATEST GEFS SHOWS THE
NRN EDGE OF A 2 INCH/24 HOUR AREA OF RAIN SKIRTING OUR SOUTHERN
ZONES AND LOWER SUSQ VALLEY FOR LATE FRIDAY THROUGH SATURDAY. THIS
IS A PRE TYPE EVENT...WITH MORE DIRECT EFFECTS /IF ANY/ FROM
JOAQUIN COMING SUNDAY INTO MONDAY.
WILL CONTINUE WITH A MAINLY DRY FCST FOR MONDAY INTO TUE.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
WIDESPREAD MVFR/IFR WILL GRADUALLY IMPROVE AS DRIER AIR FILTERS
IN FROM THE NORTH IN THE WAKE OF THE DEPARTING LOW. AS THE LOW
MOVES TOWARD NEW ENGLAND...THE PRESSURE GRADIENT WILL TIGHTEN
WITH NORTHERLY WINDS OF 10-15 KT GUSTING TO 20-25 KT COMMON BY
AFTERNOON.
VFR CONDITIONS ARE EXPECTED OVER MOST OF THE AREA TONIGHT INTO
THURSDAY
OUTLOOK...
FRI...RAIN LIKELY WITH RESTRICTIONS DEVELOPING...ESP SOUTHEAST
HALF. GUSTY WINDS POSS.
SAT-SUN...RAIN LIKELY WITH WIDESPREAD RESTRICTIONS. GUSTY WINDS
POSS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LA CORTE/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/MARTIN
AVIATION...LA CORTE
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
1013 AM CDT WED SEP 30 2015
.UPDATE...
UPDATED THE SUITE OF FORECAST PRODUCTS TO REMOVE MENTION OF PATCHY
FOG EARLIER THIS MORNING. TWEAKED HRLY TEMP...DEWPOINT...SKY
CONDITION...AND WIND SPEED/DIRECTION GRIDS. PER LATEST HRRR MODEL
RUNS...AND IN LINE WITH CURRENT REGIONAL RADAR IMAGERY...TAILORED
BEST PCPN CHANCES OF RAINFALL THRU AFTERNOON HOURS ACROSS UPPER
CUMBERLAND REGION...WITH DECREASING RAINFALL CHANCES FOR OTHER
LOCATIONS ACROSS MID STATE.
&&
.PREV DISCUSSION.../ISSUED 636 AM CDT WED SEP 30 2015/
AVIATION UPDATE...FOR 12Z TAF`S.
BNA/CKV/CSV...UPPER TROUGH IS SITUATED OVER MIDDLE TENNESSEE THIS
MORNING WITH LOW CLOUDS AND A FEW SHOWERS ALREADY MOVING INTO THE
MID STATE. WITH THE DEEPER MOISTURE EAST OF MIDDLE TENNESSEE, FOG
AND LOW STRATUS WILL BE WORSE AT CSV, WITH CONDITIONS IMPROVING
FARTHER WEST. MAINLY SCATTERED SHOWERS ARE IN THE FORECAST TODAY,
AND GIVEN THE DIFFICULTY IN NAILING DOWN A SPECIFIC TIME AT EACH
TERMINAL, WILL HANDLE WITH VCSH REMARKS FOR NOW. WINDS WILL
INCREASE DURING THE DAY AS THE SURFACE PRESSURE GRADIENT TIGHTENS
UP. WINDS SHOULD STAY UP ENOUGH OVERNIGHT TO PREVENT DENSE FOG,
BUT CIGS WILL DROP BACK DOWN AFTER 00Z.
PREV DISCUSSION... /ISSUED 547 AM CDT WED SEP 30 2015/
UPDATE...BAND OF SCATTERED TO NUMEROUS SHOWERS HAS NOW EDGED INTO
NORTH-CENTRAL MIDDLE TN, JUST NORTH OF NASHVILLE, AND SHOULD
CONTINUE DROPPING EAST SOUTHEAST THROUGH MID-MORNING. AS A RESULT,
HAVE LOWERED RAIN TODAY`S POPS JUST A BIT OVER WESTERN COUNTIES,
AND REPLACED THE WORDING OF "SCATTERED" TO "CHANCE" TO REFLECT A
LOWERED CONFIDENCE FOR MEASURABLE RAIN TODAY. OTHERWISE, NO CHANGE
TO PREVIOUS FORECAST.
WILL RELEASE A NEW SUITE OF PRODUCTS TO REFLECT THESE "WESTERN
ADJUSTMENTS" SHORTLY.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 72 59 68 54 / 30 10 20 40
CLARKSVILLE 70 56 68 52 / 20 10 10 20
CROSSVILLE 72 57 62 52 / 60 30 50 60
COLUMBIA 74 59 70 52 / 30 10 20 30
LAWRENCEBURG 75 59 70 53 / 30 10 10 20
WAVERLY 71 58 70 52 / 20 10 10 20
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
1111 AM PDT WED SEP 30 2015
.SYNOPSIS...SHOWERS WILL MOVE THROUGH TODAY THROUGH THURSDAY
MORNING AS MOISTURE MOVES ONSHORE. A WARMING AND DRYING TREND
FRIDAY AND SATURDAY AS HIGH PRESSURE BUILDS BEHIND THE TROUGH.
ANOTHER COLD TROUGH WILL DIVE DOWN THE COAST SUNDAY BRINGING A
SHOT OF COOLER TEMPERATURES AND A SLIGHT CHANCE OF SHOWERS. DRY
AND SEASONABLE WEATHER RETURNS EARLY NEXT WEEK.
&&
.DISCUSSION...AS OF 9:30 AM PDT WEDNESDAY...KMUX RADAR ALONG WITH
REPORTS FROM THE PUBLIC INDICATE SOME SHOWERS ACROSS OUR CWA AT
THIS HOUR. CURRENT BAND IS STRETCHING SW TO NE THROUGH MONTEREY
BAY REGION UP TO SOUTHERN PARTS OF MARIN AND NAPA COUNTIES. DID A
FORECAST UPDATE THIS MORNING TO INCREASE POPS AND QPF AMOUNTS PLUS
MOVE THE BEST CHANCE FOR PRECIP A BIT FARTHER NORTH. WILL DO
ADDITIONAL UPDATES AS NEEDED DURING THE SHIFT. LATEST MODEL
GUIDANCE CONTINUES TO SHOW SHOWERS ENDED TOMORROW.
.PREVIOUS DISCUSSION...FORECAST FOCUS WILL DEAL WITH SOME SHOWER
CHANCES THE NEXT 24 HOURS AND THEN A TROUGH PASSAGE ON SUNDAY.
IN THE SHORT TERM...PLENTY OF HIGH CLOUDS CONTINUE TO STREAM OVER
THE BAY AREA AND CENTRAL CALIFORNIA WITH AN UPPER LOW CENTERED OUT
NEAR 35N/130W. THE ECMWF MODEL WAS THE FIRST TO SUGGEST SOME
LIGHT SHOWERS COULD BREAK OUT TODAY...MAINLY FOR AREAS SOUTH OF
SAN FRANCISCO. STILL NOT GETTING A LOT OF BUY-IN FROM THE NAM AND
GFS ALTHOUGH THE JUST RECEIVED 06Z GFS IS SHOWING SOME LIGHT QPF.
HOWEVER THE RAP AND HRRR MESOSCALE MODELS ARE GENERATING SOME
LIGHT QPF THROUGH THE DAY. IR CLOUD TOPS SHOWING -40 CELSIUS WITH
THE KMUX RADAR STARTING TO PICK UP SOME RETURNS OFFSHORE WEST OF
BIG SUR. FORECAST FOR TODAY WILL SHOW SLIGHT CHANCE OF SHOWERS OR
SPRINKLES...MAINLY FOCUSED OVER SANTA CRUZ COUNTY AND NORTHERN
MONTEREY/SAN BENITO. OFFICIAL FORECAST WILL KEEP QPF NUMBERS VERY
LIGHT ON THE ORDER OF A FEW HUNDREDTHS.
UPPER TROUGH AXIS...WEAK SURFACE BOUNDARY AND COOL ADVECTION ALOFT
WILL PRODUCE SOME WEAK LIFT AND INSTABILITY OVERNIGHT INTO
THURSDAY MORNING SO WILL KEEP THE SLIGHT CHANCE OF SHOWERS GOING
THROUGH THE PERIOD. THE ECMWF CONTINUES TO BE THE WETTEST MODEL
SHOWING 0.25 BY THURSDAY MORNING OVER AN AREA FROM SANTA CRUZ TO
MT HAMILTON AND SOUTHWARD TOWARDS MONTEREY AND HOLLISTER. PRECIP
AMOUNTS WILL MORE LIKELY BE SPOTTY AND EXPECTING HIGHEST TOTALS
AROUND 0.10 ON AVERAGE. FORECAST REMAINS DRY FOR THE NORTH BAY THE
NEXT 24 HOURS.
BY THURSDAY AFTERNOON THE PARENT LOW WILL MOVE INLAND AND HIGH
PRESSURE WILL BEGIN TO BUILD AS TROUGH AXIS SHIFTS INLAND. THIS
WILL LEAD TO A NOTED WARMING AND DRYING TREND FOR FRIDAY...LASTING
RIGHT THROUGH SATURDAY AFTERNOON. EXPECT WIDESPREAD READINGS FROM
THE UPPER 70S THROUGH MID 80S.
BY SATURDAY NIGHT A COLD UPPER LOW WILL DROP DOWN FROM BRITISH
COLUMBIA. THE CORE OF THE SYSTEM LOOKS VERY DRY SO THE MAIN
IMPACT WILL BE COOLER TEMPERATURES AND SOME GUSTY WINDS. COOLER
TEMPERATURES ON SUNDAY AS THE LOW PASSES OVER THE REGION. THERE IS
A SLIGHT CHANCE OF A SHOWER...MAINLY OVER THE EASTERN HILLS OF
SANTA CLARA AND SAN BENITO COUNTY DUE TO STEEP LAPSE RATES ALOFT
BUT MOISTURE IS LACKING WITH THE SYSTEM AND ANY PRECIP CHANCES
LOOK SLIGHT AT BEST.
THE LOW MOVES INLAND BY SUNDAY NIGHT...LEADING TO A RETURN OF DRY
AND SEASONABLE WEATHER MONDAY THROUGH WEDS OF NEXT WEEK.
&&
.AVIATION...AS OF 11:11 AM PDT WEDNESDAY...THE CURRENT VISIBLE
SATELLITE IMAGE IS SHOWING A STREAM OF HIGH CLOUDS AND TROPICAL
MOISTURE PASSING OVER THE FORECAST AREA THIS MORNING. KMUX DOPPLER
RADAR IS INDICATING THAT LIGHT SHOWERS ARE OCCURRING OVER THE SAN
FRANCISCO BAY AREA WITH A FEW ECHOS APPROACHING THE MONTEREY
COAST. THE HIGHER RESOLUTION FORECAST MODELS ARE NOT DOING A GOOD
JOB WITH THE CURRENT SCENARIO...SO THIS WILL BE A LOW CONFIDENCE
FORECAST WITH SHOWERS STICKING AROUND THROUGH AT LEAST LATE THIS
EVENING.
VICINITY OF KSFO...VFR IS ANTICIPATED TO PREVAIL THROUGH THE
FORECAST PERIOD WITH BASES DROPPING TO SCT025 AND CIGS FALLING TO
OVC050 BY THIS EVENING. SHOWERS WILL BE POSSIBLE THROUGHOUT THE
DAY TODAY. GENERALLY LIGHT WESTERLY WINDS ARE ANTICIPATED TO
INCREASE TO 10 KT BY THIS AFTERNOON.
CONFIDENCE IS LOW.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR IS ANTICIPATED TO PREVAIL THROUGH THE
FORECAST PERIOD WITH BASES DROPPING TO SCT050 AND CIGS FALLING TO
OVC050 BY THIS EVENING. SHOWERS WILL BE POSSIBLE THROUGHOUT THE
DAY TODAY. GENERALLY LIGHT WESTERLY WINDS ARE ANTICIPATED TO
INCREASE TO 10 KT BY THIS AFTERNOON.
CONFIDENCE IS LOW.
&&
.MARINE...AS OF 4:45 AM PDT WEDNESDAY...WEAK LOW PRESSURE OFF THE
COAST WILL KEEP LIGHT WINDS THROUGH THURSDAY. HIGH PRESSURE WILL
BUILD OVER THE EASTERN PACIFIC FRIDAY AND SATURDAY RESULTING IN
INCREASING NORTHWEST WINDS.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...NONE.
$$
PUBLIC FORECAST: BELL/RWW
AVIATION: LARRY
MARINE: W PI
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
928 AM PDT WED SEP 30 2015
.SYNOPSIS...SHOWERS WILL MOVE THROUGH TODAY THROUGH THURSDAY
MORNING AS MOISTURE MOVES ONSHORE. A WARMING AND DRYING TREND
FRIDAY AND SATURDAY AS HIGH PRESSURE BUILDS BEHIND THE TROUGH.
ANOTHER COLD TROUGH WILL DIVE DOWN THE COAST SUNDAY BRINGING A
SHOT OF COOLER TEMPERATURES AND A SLIGHT CHANCE OF SHOWERS. DRY
AND SEASONABLE WEATHER RETURNS EARLY NEXT WEEK.
&&
.DISCUSSION...AS OF 9:30 AM PDT WEDNESDAY...KMUX RADAR ALONG WITH
REPORTS FROM THE PUBLIC INDICATE SOME SHOWERS ACROSS OUR CWA AT
THIS HOUR. CURRENT BAND IS STRETCHING SW TO NE THROUGH MONTEREY
BAY REGION UP TO SOUTHERN PARTS OF MARIN AND NAPA COUNTIES. DID A
FORECAST UPDATE THIS MORNING TO INCREASE POPS AND QPF AMOUNTS PLUS
MOVE THE BEST CHANCE FOR PRECIP A BIT FARTHER NORTH. WILL DO
ADDITIONAL UPDATES AS NEEDED DURING THE SHIFT. LATEST MODEL
GUIDANCE CONTINUES TO SHOW SHOWERS ENDED TOMORROW.
.PREVIOUS DISCUSSION...FORECAST FOCUS WILL DEAL WITH SOME SHOWER
CHANCES THE NEXT 24 HOURS AND THEN A TROUGH PASSAGE ON SUNDAY.
IN THE SHORT TERM...PLENTY OF HIGH CLOUDS CONTINUE TO STREAM OVER
THE BAY AREA AND CENTRAL CALIFORNIA WITH AN UPPER LOW CENTERED OUT
NEAR 35N/130W. THE ECMWF MODEL WAS THE FIRST TO SUGGEST SOME
LIGHT SHOWERS COULD BREAK OUT TODAY...MAINLY FOR AREAS SOUTH OF
SAN FRANCISCO. STILL NOT GETTING A LOT OF BUY-IN FROM THE NAM AND
GFS ALTHOUGH THE JUST RECEIVED 06Z GFS IS SHOWING SOME LIGHT QPF.
HOWEVER THE RAP AND HRRR MESOSCALE MODELS ARE GENERATING SOME
LIGHT QPF THROUGH THE DAY. IR CLOUD TOPS SHOWING -40 CELSIUS WITH
THE KMUX RADAR STARTING TO PICK UP SOME RETURNS OFFSHORE WEST OF
BIG SUR. FORECAST FOR TODAY WILL SHOW SLIGHT CHANCE OF SHOWERS OR
SPRINKLES...MAINLY FOCUSED OVER SANTA CRUZ COUNTY AND NORTHERN
MONTEREY/SAN BENITO. OFFICIAL FORECAST WILL KEEP QPF NUMBERS VERY
LIGHT ON THE ORDER OF A FEW HUNDREDTHS.
UPPER TROUGH AXIS...WEAK SURFACE BOUNDARY AND COOL ADVECTION ALOFT
WILL PRODUCE SOME WEAK LIFT AND INSTABILITY OVERNIGHT INTO
THURSDAY MORNING SO WILL KEEP THE SLIGHT CHANCE OF SHOWERS GOING
THROUGH THE PERIOD. THE ECMWF CONTINUES TO BE THE WETTEST MODEL
SHOWING 0.25 BY THURSDAY MORNING OVER AN AREA FROM SANTA CRUZ TO
MT HAMILTON AND SOUTHWARD TOWARDS MONTEREY AND HOLLISTER. PRECIP
AMOUNTS WILL MORE LIKELY BE SPOTTY AND EXPECTING HIGHEST TOTALS
AROUND 0.10 ON AVERAGE. FORECAST REMAINS DRY FOR THE NORTH BAY THE
NEXT 24 HOURS.
BY THURSDAY AFTERNOON THE PARENT LOW WILL MOVE INLAND AND HIGH
PRESSURE WILL BEGIN TO BUILD AS TROUGH AXIS SHIFTS INLAND. THIS
WILL LEAD TO A NOTED WARMING AND DRYING TREND FOR FRIDAY...LASTING
RIGHT THROUGH SATURDAY AFTERNOON. EXPECT WIDESPREAD READINGS FROM
THE UPPER 70S THROUGH MID 80S.
BY SATURDAY NIGHT A COLD UPPER LOW WILL DROP DOWN FROM BRITISH
COLUMBIA. THE CORE OF THE SYSTEM LOOKS VERY DRY SO THE MAIN
IMPACT WILL BE COOLER TEMPERATURES AND SOME GUSTY WINDS. COOLER
TEMPERATURES ON SUNDAY AS THE LOW PASSES OVER THE REGION. THERE IS
A SLIGHT CHANCE OF A SHOWER...MAINLY OVER THE EASTERN HILLS OF
SANTA CLARA AND SAN BENITO COUNTY DUE TO STEEP LAPSE RATES ALOFT
BUT MOISTURE IS LACKING WITH THE SYSTEM AND ANY PRECIP CHANCES
LOOK SLIGHT AT BEST.
THE LOW MOVES INLAND BY SUNDAY NIGHT...LEADING TO A RETURN OF DRY
AND SEASONABLE WEATHER MONDAY THROUGH WEDS OF NEXT WEEK.
&&
.AVIATION...AS OF 4:45 AM PDT WEDNESDAY...FT ORD PROFILER SHOWS NO
SIGN OF AN INVERSION. PATCHY LOW CLOUDS HAVE DEVELOPED BUT VFR
CONDITIONS ARE EXPECTED TODAY WITH MID AND HIGH CLOUDS. RADAR IS
PICKING UPS A FEW SHOWERS SW OF THE MRY BAY AREA WHICH MAY AFFECT
THE MRY BAY AREA AFTER 12Z AND THE SFO BAY AREA AFTER 16Z.
VICINITY OF KSFO...VFR WITH MID AND HIGH LEVEL CLOUDINESS. ISOLATED
SHOWERS POSSIBLE 16Z-03Z.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR WITH MID AND HIGH CLOUDINESS.
ISOLATED SHOWERS POSSIBLE THROUGH 20Z.
&&
.MARINE...AS OF 4:45 AM PDT WEDNESDAY...WEAK LOW PRESSURE OFF THE
COAST WILL KEEP LIGHT WINDS THROUGH THURSDAY. HIGH PRESSURE WILL
BUILD OVER THE EASTERN PACIFIC FRIDAY AND SATURDAY RESULTING IN
INCREASING NORTHWEST WINDS.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...NONE.
$$
PUBLIC FORECAST: BELL/RWW
AVIATION: W PI
MARINE: W PI
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AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
320 PM MDT WED SEP 30 2015
.SHORT TERM...(THIS AFTERNOON THROUGH THURSDAY)
ISSUED AT 320 PM MDT WED SEP 30 2015
SCATTERED SHOWERS HAVE DEVELOPED IN THE MOUNTAINS AS EXPECTED...
AND A FEW OF THESE WILL BE DRIFTING ONTO THE PLAINS EARLY THIS
EVENING. ISOLATED THUNDERSTORMS WILL OCCUR WITH JUST ENOUGH
INSTABILITY AND MARGINAL CAPES AROUND 200 J/KG. THERE IS AN UPPER
LEVEL JET MAX JUST TO OUR NORTH...SO A FEW SHOWERS COULD SPREAD A
LITTLE FARTHER EAST ON THE PLAINS THROUGH THE EVENING SO ADJUSTED
ACCORDINGLY. HRRR COVERAGE SEEMS TOO HIGH...BUT RAP13 LOOKS MORE
REASONABLE GIVEN THE RATHER DRY/STABLE AIRMASS.
WITH REGARD TO PLAINS STRATUS AND FOG...LOOK LIKE A VERY SIMILAR
SETUP TO LAST NIGHT WITH FOG POTENTIALLY WRAPPING BACK TO GREELEY
AND LOVELAND/FORT COLLINS AREA BY DAYBREAK.
ON THURSDAY...UPPER LEVEL RIDGE AXIS BUILDS OVER THE FORECAST
AREA. WITH WARMING ALOFT...SHOULD BE SOME SUPPRESSION OF
CONVECTION BUT STILL ENOUGH DAYTIME HEATING FOR A FEW LATE DAY
STORMS. PLAINS SHOULD REMAIN CAPPED THROUGH MOST OF THE DAY.
TEMPERATURES ONCE AGAIN SIMILAR TO THOSE OBSERVED TODAY AND CLOSE
TO 10 DEGREES ABOVE NORMAL. EXCEPTION WOULD BE OVER THE FAR
NORTHEAST CORNER WHERE STRATUS IS MORE PERSISTENT.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 320 PM MDT WED SEP 30 2015
THURSDAY NIGHT INTO FRIDAY AN UPPER LEVEL TROUGH WILL BE OVER THE
WEST COAST MOVING INLAND. HEIGHT FALLS AHEAD OF THE TROUGH WILL
HELP TO BRING SURFACE WINDS MORE SE OVER THE PLAINS. THIS WILL AID
IN THE FORMATION OF A DENVER CYCLONE AND SUBSEQUENT CONVERGENCE
AREA SSE OF DENVER. INCREASING MOISTURE BEING PULLED NORTHWARD
FROM THE MID LEVEL SW FLOW ALOFT WILL HELP TO INCREASE INSTABILITY
BY FRIDAY AFTERNOON. THESE INGREDIENTS COMBINED WITH THE
POTENTIAL FOR DECENT SHEAR INCREASE THE CHANCES FOR AFTERNOON
STRONG STORMS FRIDAY TO INCLUDE BRIEF HEAVY RAIN...LARGE HAIL AND
GUSTY WINDS. AS THE TROUGH CONTINUES TO MAKE ITS WAY ACROSS THE
GREAT BASIN THE CONVECTION WILL TURN TO SHOWERS OVERNIGHT INTO
SATURDAY.
SATURDAY WILL SEE THE UPPER LEVEL TROUGH SWING NORTHWARD OVER
WYOMING BRINGING SHOWERS AND LOWER CLOUDS FOR THE MORNING HOURS.
THE TROUGH IS PROGGED TO MOVE OUT BY THE AFTERNOON ENDING SHOWERS
BUT WITH LINGERING HIGH LEVELS OF MOISTURE BEHIND IT CLOUDS WILL
STICK AROUND KEEPING TEMPERATURES COOLER. HIGHS ON SATURDAY WILL
BE BELOW NORMAL ONLY REACHING INTO THE MID 60S WITH 50S IN THE
MOUNTAINS. THE TROUGH FRIDAY NIGHT INTO SATURDAY WILL COOL
TEMPERATURES IN THE MOUNTAINS ENOUGH FOR AREAS ABOVE 10,000 FT
POSSIBLY SEEING A RAIN AND SNOW MIX. LITTLE TO NO ACCUMULATION IS
EXPECTED HOWEVER.
FOR SUNDAY AND MONDAY THE UPPER LEVEL TROUGH WILL EXIT BRINGING
RIDGING OVER NE COLORADO AHEAD OF THE NEXT UPPER LEVEL SYSTEM.
FLOW WILL SWITCH TO A WARMER MORE SW DIRECTION BRINGING
TEMPERATURES BACK INTO THE 70S BY MONDAY AND KEEPING CONDITIONS
DRIER WITH ONLY A SMALL CHANCE OF SOME AFTERNOON CONVECTION IN THE
HIGHER MOUNTAINS.
FOR TUESDAY THE LATEST GFS AND EC MODEL RUNS ARE IN SLIGHTLY
BETTER AGREEMENT WITH THE MOVEMENT OF THE NEXT UPPER LEVEL LOW OUT
OF CANADA. BOTH MODELS TURN THE SYSTEM INTO AN OPEN WAVE AND BRING
IT EAST OVER UTAH AND INTO NW COLORADO BY TUESDAY AFTERNOON. THE
EC IS SLIGHTLY FASTER THAN THE GFS SOLUTION BUT BOTH BRING
PRECIPITATION TO NE COLORADO AND COOLER TEMPERATURES MOVING INTO
WEDNESDAY. WILL STICK WITH A SLIGHT CHANCE FOR NOW TO SEE HOW THE
NEXT FEW MODEL RUNS PLAY OUT.
&&
.AVIATION...(FOR THE TAFS THROUGH 00Z THURSDAY AFTERNOON)
ISSUED AT 320 PM MDT WED SEP 30 2015
VFR CONDITIONS WILL PERSIST AT THE DENVER METRO AREA AIRPORTS
THROUGH THURSDAY. FARTHER NORTH...KFNL AND KGXY WILL BE ON THE
EDGE OF FOG FORMATION TONIGHT BUT HAVE POTENTIAL FOR 1/4SM
VISIBILITY FOR A COUPLE HOURS CENTERED AROUND 12Z-13Z. ISOLATED
SHOWERS ARE STILL EXPECTED TO DRIFT OFF THE FRONT RANGE 22Z-
03Z...BUT NO VISIBILITY RESTRICTION WILL OCCUR. RISK OF THUNDER AT
OR LESS THAN 10 PERCENT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BARJENBRUCH
LONG TERM...BOWEN
AVIATION...BARJENBRUCH
AREA FORECAST DISCUSSION
NWS PADUCAH KY
240 PM CDT WED SEP 30 2015
.NEAR TERM...(Rest of today)
Issued at 240 PM CDT WED SEP 30 2015
The RAP has done a good job with the infiltration of lower level
dry air from the NNE, and a better job with short term temps,
slightly warmer NW and cooler toward the TN border with KY. Will
continue with its trends through 00z, gradual decreasing clouds
from the north.
&&
.SHORT TERM...(Tonight through Friday night)
Issued at 240 PM CDT WED SEP 30 2015
Heights will continue to lower over the SE U.S. with a h5 closed low
forecast to develop close to the TN valley next 24 hours. The low
will then drop SSE. Decreasing clouds most areas, though they may
hold on across the Pennyrile. Will have a dry forecast through
Thursday. Thursday night through Friday night will bring a chance of
showers into the eastern part of the CWFA as the models rotate
moisture/clouds and modest lift back west into the area. The GFS/NAM
solutions are a tad more aggressive with scattered shower chances
vs. the latest ECMWF. We have raised our numerical PoP values
slightly, but not as aggressively as MOS across the east given lower
confidence. We generally favored MOS temps, but went at or slightly
below values for highs Friday across the west KY Pennyrile.
.LONG TERM...(Saturday through Tuesday)
Issued at 240 PM CDT WED SEP 30 2015
At the start of the period, the models are in moderate agreement
with a closed low over the SE U.S. and Joaquin somewhere east of FL.
The divergence in solutions is swift from 12z Sunday on with respect
to Joaquin and the placement/transition of the SE closed low into
early next week. Thankfully, after looking over the past 3 days
worth of runs for the Sunday through Tuesday time frame, our weather
looks uneventful regardless of how the pattern evolves (including
Joaquin). The only way this changes is if somehow either Joaquin, or
the upper low ends up notably farther west than forecast. We will
carry just a slight chance of showers SW IN/west KY Pennyrile
Saturday, then dry Saturday night through Tuesday. Looking at the
past 3 MOS sets, Saturday still on track to be coolish. The overall
MOS trend for Sunday through Tuesday is warmer, especially
Monday/Tuesday. We adjusted up as a result given the prospect for
less cloud cover and a rise in heights.
&&
.AVIATION...
Issued at 1153 AM CDT WED SEP 30 2015
MVFR cigs continue generally south of a KMDH-KAJG line with breaks
continuing to push south across southern IL. Will depict a gradual
improvement through 00z as drier low level air continues to filter
south across the region, with north winds around 10 kts
persisting.
Models depict mid clouds may persist tonight. NAM-RAP models
advect low-level moisture in from the NE Thursday morning. We
introduced a SCT deck just below 3k/ft in case this comes to
fruition. Later shifts can adjust. North winds generally around 5
kts tonight will become NNE and gusty Thursday morning. Some gusts
may climb just over 20 kts.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
CN
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
620 PM EDT WED SEP 30 2015
.SYNOPSIS...
A COLD FRONT CROSSES THE MID ATLANTIC REGION LATE TODAY AND THIS
EVENING...THEN STALLS ALONG THE COAST THURSDAY AND FRIDAY. THE FRONT
PUSHES BACK ONSHORE OVER THE WEEKEND. MEANWHILE...HURRICANE JOAQUIN
LIFTS WELL OFF THE SOUTHEAST COAST SATURDAY...LOCATING JUST OFF THE
MID ATLANTIC COAST SUNDAY AND OFF THE DELMARVA MONDAY MORNING.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
LATEST SFC ANALYSIS PLACES THE COLD FRONT ACROSS THE SE HALF OF THE
LOCAL AREA THIS AFTERNOON. SCATTERED TO NUMEROUS SHOWERS WITH
EMBEDDED THUNDER HAVE DEVELOPED AHEAD OF THE FRONT ACROSS SE VA/NE
NC IN A WARM/MOIST AND MODESTLY UNSTABLE AIR MASS. ANOTHER AREA OF
SHOWERS HAS DEVELOPED OVER THE NRN NECK BACK INTO CENTRAL VA ALONG
THE IMMEDIATE FRONT. RAP MESO-ANALYSIS STILL DEPICTS 30-35 KT
EFFECTIVE SHEAR...SO CANNOT RULE OUT A FEW GUSTY WINDS UNDER THE
STRONGEST STORMS...BUT NO SEVERE WEATHER IS EXPECTED. BASED ON
INCREASING WINDS ALOFT...SHORTWAVE ENERGY IN DEEP LAYER SWLY FLOW
AND DEEP MOISTURE CONVERGENCE...WILL CONTINUE TO CARRY LIKELY POPS
THRU THIS EVENING SE VA/NE NC.
COLD FRONT REACHES THE COAST/WRN ATLANTIC AND STALLS IN SWLY FLOW
ALOFT. FAVORABLE DYNAMICS...A WARM/MOIST AIR MASS AND ISENTROPIC
LIFT WILL RESULT IN ONGOING LIKELY POPS...RAMPING UP TO LOW END
CATEGORICAL ACROSS THE SOUTHEAST. HI-RES AND RAP MODELS SEEM TO
HANDLE THE EVOLUTION OVERNIGHT WELL...SO HAVE TRENDED THAT WAY. QPF
AMOUNTS THRU THE OVERNIGHT WILL RANGE FROM UNDER A FEW TENTHS OF AN
INCH NW HALF TO AROUND AN INCH SE VA/NE NC. OTHERWISE...CLOUDY
CONDITIONS PERSIST. LOWERING DEWPOINTS WILL ALLOW TEMPS TO DROP INTO
THE MID-UPPER 50S PIEDMONT TO MID-UPPER 60S SE.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
INCREASING CONFIDENCE ON THE POTENTIAL FOR A SIGNIFICANT
PREDECESSOR RAIN EVENT DEVELOPING THURSDAY AFTERNOON INTO
SATURDAY. LATEST GEFS GUIDANCE CONTINUES TO INDICATE NEGATIVE
HEIGHT ANOMALIES DEVELOPING OVER THE DEEP SOUTH/GULF COAST (DEEP
TROUGH)...WITH STRONG POSITIVE HEIGHT ANOMALIES ACROSS THE HUDSON
BAY (UPPER HIGH). THESE ANOMALIES WILL PERSIST THRU THE WEEKEND.
THE RESULT OF THIS AMPLIFYING PATTERN IS A CLOSED/CUT OFF UPPER
LOW ACROSS THE INTERIOR SE CONUS BY FRIDAY. THE PATTERN ALSO
SUPPORTS ANOMALOUS MOISTURE FLUX/ONSHORE FLOW WITH THE SREF
INDICATING ANOMALIES OF + 4 STD DEV BY FRIDAY AND +6 BY FRIDAY
NIGHT AND SATURDAY.
THE COLD/COASTAL FRONT RETROGRADES SLIGHTLY NNW THU...BEFORE
STALLING ALONG THE COAST IN SWLY FLOW ALOFT. STRONG MID/UPPER
LEVEL DYNAMICS PROGGED TO BE OVER THE REGION THU AFTERNOON INTO
FRI/FRI NIGHT THANKS TO THE UPPER LOW AND AN EXITING 100+ KT JET
STREAK. OVERRUNNING COMMENCES WITH RAIN INCREASING IN COVERAGE AND
INTENSITY THU AFTERNOON INTO FRIDAY NIGHT. CONTINUED THE TREND OF
FOLLOWING CLOSE TO 12Z/30 WPC QPF...WHICH RESULTS IN STORM TOTAL
QPF AMOUNTS OF 5 TO 7 INCHES!!! THROUGH SATURDAY. AFTER
COORDINATION WITH NEIGHBORING OFFICES...HAVE OPTED TO HOLD OFF ON
A FLOOD WATCH ATTM AS THE HEAVIEST PRECIP IS EXPECTED THURSDAY
NIGHT-FRI (3RD PERIOD). NASA SPORT GUIDANCE INDICATES RECENT
RAINFALL HAS SATURATED MUCH OF THE REGION...AND WITH ADDITIONAL
RAINFALL EXPECTED TODAY AND TONIGHT (WEDS-WEDS NIGHT)...SOILS WILL
BE RATHER MOIST TO BEGIN THE EVENT. MMEFS GUIDANCE INDICATES
WIDESPREAD RIVER FLOODING/AREAL FLOODING IS LIKELY AND WILL
HIGHLIGHT IN THE HWO. ATTENTION THEN TURNS TO JOAQUIN ON SUNDAY.
HURRICANE JOAQUIN (AS OF THE 2 PM NHC UPDATE)...
UNCERTAINTY CONTINUES TO SURROUND THE EXACT TRACK AND STRENGTH OF
HURRICANE JOAQUIN LATE THIS WEEK AND INTO THE WEEKEND. FOLLOWING
CLOSELY TO NHC FORECASTS...JOAQUIN IS FORECAST TO REMAIN IN THE
VICINITY OF THE BAHAMAS THROUGH FRIDAY MORNING...BEFORE LIFTING NWD
FRI INTO FRI NIGHT AND BECOMING A MAJOR HURRICANE WELL OFF THE FL
COAST. JOAQUIN THEN ACCELERATES NWD...WEAKENING...WITH UNCERTAINTY
BECOMING PROBLEMATIC THEREAFTER. GFS CONTINUES A SRN TREND...WITH
THE 30/12Z GFS BRINGING THE CIRCULATION INLAND IN THE CAROLINAS.
HOWEVER...THE GEFS ENSEMBLES STILL SHOW A CONSIDERABLE SPREAD. THE
30/00Z ECMWF CONTINUES TO KEEP THE CIRCULATION WELL OFFSHORE.
MID/UPPER LEVEL FLOW SUGGESTS THAT EACH SCENARIO COULD BE POSSIBLE.
FOLLOWING A MODEL MEAN...NHC TRACKS JOAQUIN OFF THE MID ATLANTIC
COAST SUNDAY AND SUNDAY NIGHT. THIS TRACK WOULD FAVOR ADDITIONAL
RAINFALL SUNDAY...BUT AGAIN...CONFIDENCE IS NOT HIGH. EXPECT
INCREASING CONFIDENCE THE NEXT 24 HOURS AS BOTH THE DEEPENING TROUGH
AND JOAQUIN ARE BETTER SAMPLED.
GALE CONDITIONS...HIGH SEAS/WAVES AND MODERATE TO LOCALLY MAJOR
COASTAL FLOODING ARE ALSO EXPECTED. PLEASE REFER TO MARINE AND TIDES
SECTIONS BELOW.
OTHERWISE...EXPECT CLOUDY AND COOL CONDITIONS WITH AN IN-SITU CAD
WEDGE OVER THE PIEDMONT. HIGHS THURSDAY AND FRIDAY RANGE FROM THE
MID/UPPER 50S NW...TO THE LOW/MID 70S FAR SE IN CLOSER PROXIMITY TO
THE FRONTAL BOUNDARY. WARMER OVER THE PIEDMONT SAT AND SUN...WITH
HIGHS IN THE LOW/MID 60S NW TO MID 70S SE.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
COMPLICATED...PTNTLLY VERY STORMY AND HIGHLY IMPACTFUL PD INTO
THE WKND. THERE RMN UNKNOWNS ATTM. HOW DOES HURRICANE JOAQUIN
INTERACT W/ DEEP NEGATIVE/HIGHLY ANOMALOUS UPR LVL LO PRES AS IT
TRACKS THROUGH THE CSTL SE STATES FRI NGT INTO SAT? DOES THE
HURRICANE BECOME ENTRAINED/ABSORBED IN THE OVERALL PATTERN OR RMN
SEPARATE? 00Z/30 GFS/CMC AND SEVERAL GEFS MEMBERS DEPICT A MORE
WESTWARD TRACK OF THE HURRICANE...WHILE THE 00Z/30 ECMWF AND
SEVERAL GEFS MEMBERS SHOW A NE TRACK OF THE HURRICANE WELL
OFFSHORE...WHICH DOES NOT CAST ANYMORE CLARITY ON THE POTENTIAL
EVENT.
REGARDLESS OF HOW THE SYSTEMS INTERACT...RA (MDT/HVY) A GOOD BET INTO
SUN. (THOUGH PINPOINTING LOCATION OF EXCESSIVE AMTS UNCERTAIN
ATTM). ALSO...CONCERNS WILL BE FOR DEGREE OF CSTL FLOODING...AND
HOW STRONG WNDS WILL BECOME (ESP ON THE WTRS). THE 12Z/29 ECMWF
ONLY SLOLY TRACKS THE CLOSED UPR LVL LO PRES ENE THROUGH THE RGN
SUN/MON...WHICH WOULD RESULT IN CONTD RA...WND AND CSTL FLOODING
EFFECTS. FOR NOW...BLENDED THE FCST W/ HPC AND CONT WILL DRYING
TREND FM SUN AFTN THROUGH EARLY NEXT WK (BUT THAT IS NOT A
GUARANTEE ATTM).
HI TEMPS IN THE 60S TO L70S EACH DAY. LO TEMPS IN THE 50S TO L60S
AT NGT.
&&
.AVIATION /22Z WEDNESDAY THROUGH MONDAY/...
A COLD FRNT CROSSES THE AREA THIS EVENING...WITH S/SW WINDS AHEAD
OF THE FRNT SHIFTING TO N BEHIND THE FRNT TNGT. SHOWERS AND
THUNDERSTORMS ARE POPPING UP ACROSS THE AREA WITH HEAVY RAIN
POSSIBLE. THE FRNT STALLS OFFSHORE INTO THU LEADING TO OVERRUNNING
PCPN ACROSS THE REGION. WIDESPREAD IFR CAN BE EXPECTED DURING THAT
TIME FRAME...PERHAPS EXTENDING INTO FRI.
OUTLOOK...HEAVY RAIN AND RESTRICTED FLIGHT CONDITIONS ARE POSSIBLE
SATURDAY AND SUNDAY AS AN UPPER TROF LINGERS ACROSS THE AREA AND
HURRICANE JOAQUIN PSBLY AFFECTING THE REGION.
&&
.MARINE...
A COLD FRONT IS CROSSING THE WATERS AS OF 600 PM THIS EVENING AND
WILL CONTINUE TO PUSH EWD. THUNDERSTORMS WITH HEAVY RAINFALL...
ERRATIC WIND GUSTS...AND LIGHTNING SHOULD BE ANTICIPATED OVER THE
NEXT FEW HOURS. THE FRONT WILL THEN STALL ALONG THE COAST LATE
TONIGHT INTO FRIDAY...FOLLOWED BY CAA FROM THE NORTH. N-NE WINDS
WILL DEVELOP BEHIND THE FRONT AND SURGE DOWN THE BAY AND NRN
COASTAL WATERS THIS EVENING AND BECOME MORE WIDESPREAD OVER ALL
WATERS EARLY THU MORNING. SPEEDS WILL AVERAGE 15-25KT. IN
ADDITION...SEAS BUILD TO 5-6FT AND WAVES ON CHES BAY BUILD TO
4-5FT BY MORNING. SCA FLAGS WILL BE IN EFFECT FOR ALL WATERS BY
THU MORNING. THE PRESSURE GRADIENT TIGHTENS UP BY THU AFTN AS
STRONG HIGH PRESSURE SETTLES OVER SERN CANADA AND AN AREA OF LOW
PRESSURE STARTS TO DEVELOP OFF THE SOUTHEAST COAST. THIS WILL
RESULT IN GALE FORCE WIND GUSTS OVER COASTAL WATERS ROUGHLY NORTH
OF CAPE CHARLES LIGHT BY THU AFTN AND THEN NORTH OF THE VA/NC
BORDER BY THU EVENING...INCLUDING CHES BAY. SEAS BUILD TO 8-12 FT
AND 6-8FT SOUTH OVERNIGHT THU. KEPT GALE WARNING FOR COASTAL
WATERS N OF PARRAMORE ISLAND AND EXTENDED THE HEADLINE THROUGH FRI
AFTN/4TH PERIOD. GALE WATCH FOR CHES BAY WAS DELAYED UNTIL THU
EVENING WITH GALES NOT EXPECTED TO OCCUR UNTIL AFTER MIDNIGHT THU
NIGHT.
A COASTAL STORM DEVELOPS NEAR THE SOUTHEAST COAST ALONG THE
STALLED FRONTAL BOUNDARY FRI INTO FRI NIGHT. THERE IS STILL A
LARGE AMT OF UNCERTAINTY AS TO WHETHER TROPICAL CYCLONE JOAQUIN
GETS PULLED INTO THIS SYSTEM OR NOT. EITHER WAY...STRONG ONSHORE
WINDS AVERAGING 25-35KT WITH GUSTS OF 40-45KT ARE EXPECTED TO
CONTINUE FRI INTO THE WEEKEND WITH SEAS BUILDING TO 10-15FT BY SUN
MORNING (POSSIBLY HIGHER). CONDITIONS WILL DETERIORATE DRASTICALLY
FRI INTO THE WEEKEND. TROPICAL HEADLINES MAY BE FORTHCOMING ON
THU...SO PLEASE KEEP CHECKING THE LATEST FORECAST FOR UP TO DATE
INFORMATION.
&&
.TIDES/COASTAL FLOODING...
COASTAL FLOOD ADVISORY NOW IN EFFECT FOR THE NORTHERN NECK AS
LEWISETTA IS FORECAST TO REACH 3.4 TO 3.5 FT. WILL ALSO MAINTAIN
A COASTAL FLOOD STATEMENT FOR EAST SIDE OF CHES BAY TO INCLUDE
DORCHESTER/SOMERSET/WICOMICO FOR UPCOMING HIGH TIDE CYCLE THIS
AFTN. ELSEWHERE...WATER LEVELS GENLY REMAIN SEVERAL TENTHS OF A
FOOT BELOW MINOR FLOOD THROUGH WED.
A COLD FRONT CROSSES THE WATERS TONIGHT. FOLLOWING THIS FRONTAL
PASSAGE...NORTH TO NORTHEAST WINDS WILL INCREASE SIGNIFICANTLY.
THIS OCCURS FIRST ACRS NORTHERN AREAS...POSSIBLY DELAYED UNTIL
LATE THU/THU NIGHT ACRS THE FAR SOUTH. STILL SOME QUESTION AS TO
EXACT WIND DIRECTION (I.E NNE TO ENE)...WHICH WOULD HAVE
SIGNIFICANT CONSEQUENCES FOR THE DEGREE OF TIDAL FLOODING IN
SPECIFIC AREAS. FOR NOW HAVE SPLIT THE DIFFERENCE...WITH MINOR
FLOODING BECOMING LIKELY FOR COASTAL AREAS (ESPECIALLY FROM
WACHAPREAGUE ON NORTH BY THU AFTN). MORE SIGNIFICANT FLOODING
POSSIBLE FOR THE LOWER BAY AND ALL COASTAL AREAS BY THU EVENING
INTO FRI AND BEYOND.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...COASTAL FLOOD ADVISORY UNTIL 6 AM EDT THURSDAY FOR VAZ075-077.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM THURSDAY TO 7 PM EDT FRIDAY FOR
ANZ633-635>637.
GALE WATCH FROM THURSDAY EVENING THROUGH FRIDAY EVENING FOR
ANZ630>632-634.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT THURSDAY FOR ANZ630>632-
634.
SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 7 PM EDT FRIDAY
FOR ANZ638.
GALE WATCH FROM THURSDAY MORNING THROUGH FRIDAY EVENING FOR
ANZ654-656.
SMALL CRAFT ADVISORY UNTIL 10 AM EDT THURSDAY FOR ANZ654-656.
SMALL CRAFT ADVISORY UNTIL 7 AM EDT THURSDAY FOR ANZ650-652.
GALE WARNING FROM 7 AM THURSDAY TO 7 PM EDT FRIDAY FOR ANZ650-
652.
SMALL CRAFT ADVISORY UNTIL 7 PM EDT FRIDAY FOR ANZ658.
&&
$$
SYNOPSIS...AJZ/SAM
NEAR TERM...AJZ/SAM
SHORT TERM...AJZ/SAM
LONG TERM...ALB/DAP
AVIATION...MAS/DAP
MARINE...BMD
TIDES/COASTAL FLOODING...AKQ
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
400 PM EDT WED SEP 30 2015
.SYNOPSIS...
A COLD FRONT CROSSES THE MID ATLANTIC REGION LATE TODAY AND THIS
EVENING...THEN STALLS ALONG THE COAST THURSDAY AND FRIDAY. THE FRONT
PUSHES BACK ONSHORE OVER THE WEEKEND. MEANWHILE...HURRICANE JOAQUIN
LIFTS WELL OFF THE SOUTHEAST COAST SATURDAY...LOCATING JUST OFF THE
MID ATLANTIC COAST SUNDAY AND OFF THE DELMARVA MONDAY MORNING.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
LATEST SFC ANALYSIS PLACES THE COLD FRONT ACROSS THE SE HALF OF THE
LOCAL AREA THIS AFTERNOON. SCATTERED TO NUMEROUS SHOWERS WITH
EMBEDDED THUNDER HAVE DEVELOPED AHEAD OF THE FRONT ACROSS SE VA/NE
NC IN A WARM/MOIST AND MODESTLY UNSTABLE AIR MASS. ANOTHER AREA OF
SHOWERS HAS DEVELOPED OVER THE NRN NECK BACK INTO CENTRAL VA ALONG
THE IMMEDIATE FRONT. RAP MESO-ANALYSIS STILL DEPICTS 30-35 KT
EFFECTIVE SHEAR...SO CANNOT RULE OUT A FEW GUSTY WINDS UNDER THE
STRONGEST STORMS...BUT NO SEVERE WEATHER IS EXPECTED. BASED ON
INCREASING WINDS ALOFT...SHORTWAVE ENERGY IN DEEP LAYER SWLY FLOW
AND DEEP MOISTURE CONVERGENCE...WILL CONTINUE TO CARRY LIKELY POPS
THRU THIS EVENING SE VA/NE NC.
COLD FRONT REACHES THE COAST/WRN ATLANTIC AND STALLS IN SWLY FLOW
ALOFT. FAVORABLE DYNAMICS...A WARM/MOIST AIR MASS AND ISENTROPIC
LIFT WILL RESULT IN ONGOING LIKELY POPS...RAMPING UP TO LOW END
CATEGORICAL ACROSS THE SOUTHEAST. HI-RES AND RAP MODELS SEEM TO
HANDLE THE EVOLUTION OVERNIGHT WELL...SO HAVE TRENDED THAT WAY. QPF
AMOUNTS THRU THE OVERNIGHT WILL RANGE FROM UNDER A FEW TENTHS OF AN
INCH NW HALF TO AROUND AN INCH SE VA/NE NC. OTHERWISE...CLOUDY
CONDITIONS PERSIST. LOWERING DEWPOINTS WILL ALLOW TEMPS TO DROP INTO
THE MID-UPPER 50S PIEDMONT TO MID-UPPER 60S SE.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SUNDAY/...
INCREASING CONFIDENCE ON THE POTENTIAL FOR A SIGNIFICANT
PREDECESSOR RAIN EVENT DEVELOPING THURSDAY AFTERNOON INTO
SATURDAY. LATEST GEFS GUIDANCE CONTINUES TO INDICATE NEGATIVE
HEIGHT ANOMALIES DEVELOPING OVER THE DEEP SOUTH/GULF COAST (DEEP
TROUGH)...WITH STRONG POSITIVE HEIGHT ANOMALIES ACROSS THE HUDSON
BAY (UPPER HIGH). THESE ANOMALIES WILL PERSIST THRU THE WEEKEND.
THE RESULT OF THIS AMPLIFYING PATTERN IS A CLOSED/CUT OFF UPPER
LOW ACROSS THE INTERIOR SE CONUS BY FRIDAY. THE PATTERN ALSO
SUPPORTS ANOMALOUS MOISTURE FLUX/ONSHORE FLOW WITH THE SREF
INDICATING ANOMALIES OF + 4 STD DEV BY FRIDAY AND +6 BY FRIDAY
NIGHT AND SATURDAY.
THE COLD/COASTAL FRONT RETROGRADES SLIGHTLY NNW THURS...BEFORE
STALLING ALONG THE COAST IN SWLY FLOW ALOFT. STRONG MID/UPPER LEVEL
DYNAMICS PROGGED TO BE OVER THE REGION THURS AFTERNOON INTO FRI/FRI
NIGHT THANKS TO THE UPPER LOW AND AN EXITING 100+ KT JET STREAK.
OVERRUNNING COMMENCES WITH RAIN INCREASING IN COVERAGE AND INTENSITY
THURS AFTERNOON INTO FRIDAY NIGHT. CONTINUED THE TREND OF FOLLOWING
CLOSE TO 12Z/30 WPC QPF...WHICH RESULTS IN STORM TOTAL QPF AMOUNTS
OF 5 TO 7 INCHES!!! THROUGH SATURDAY. AFTER COORDINATION WITH
NEIGHBORING OFFICES...HAVE OPTED TO HOLD OFF ON A FLOOD WATCH ATTM
AS THE HEAVIEST PRECIP IS EXPECTED THURSDAY NIGHT-FRI (3RD PERIOD).
NASA SPORT GUIDANCE INDICATES RECENT RAINFALL HAS SATURATED MUCH OF
THE REGION...AND WITH ADDITIONAL RAINFALL EXPECTED TODAY AND TONIGHT
(WEDS-WEDS NIGHT)...SOILS WILL BE RATHER MOIST TO BEGIN THE EVENT.
MMEFS GUIDANCE INDICATES WIDESPREAD RIVER FLOODING/AREAL FLOODING IS
LIKELY AND WILL HIGHLIGHT IN THE HWO. ATTENTION THEN TURNS TO
JOAQUIN ON SUNDAY.
HURRICANE JOAQUIN (AS OF THE 2 PM NHC UPDATE)...
UNCERTAINTY CONTINUES TO SURROUND THE EXACT TRACK AND STRENGTH OF
HURRICANE JOAQUIN LATE THIS WEEK AND INTO THE WEEKEND. FOLLOWING
CLOSELY TO NHC FORECASTS...JOAQUIN IS FORECAST TO REMAIN IN THE
VICINITY OF THE BAHAMAS THROUGH FRIDAY MORNING...BEFORE LIFTING NWD
FRI INTO FRI NIGHT AND BECOMING A MAJOR HURRICANE WELL OFF THE FL
COAST. JOAQUIN THEN ACCELERATES NWD...WEAKENING...WITH UNCERTAINTY
BECOMING PROBLEMATIC THEREAFTER. GFS CONTINUES A SRN TREND...WITH
THE 30/12Z GFS BRINGING THE CIRCULATION INLAND IN THE CAROLINAS.
HOWEVER...THE GEFS ENSEMBLES STILL SHOW A CONSIDERABLE SPREAD. THE
30/00Z ECMWF CONTINUES TO KEEP THE CIRCULATION WELL OFFSHORE.
MID/UPPER LEVEL FLOW SUGGESTS THAT EACH SCENARIO COULD BE POSSIBLE.
FOLLOWING A MODEL MEAN...NHC TRACKS JOAQUIN OFF THE MID ATLANTIC
COAST SUNDAY AND SUNDAY NIGHT. THIS TRACK WOULD FAVOR ADDITIONAL
RAINFALL SUNDAY...BUT AGAIN...CONFIDENCE IS NOT HIGH. EXPECT
INCREASING CONFIDENCE THE NEXT 24 HOURS AS BOTH THE DEEPENING TROUGH
AND JOAQUIN ARE BETTER SAMPLED.
GALE CONDITIONS...HIGH SEAS/WAVES AND MODERATE TO LOCALLY MAJOR
COASTAL FLOODING ARE ALSO EXPECTED. PLEASE REFER TO MARINE AND TIDES
SECTIONS BELOW.
OTHERWISE...EXPECT CLOUDY AND COOL CONDITIONS WITH AN IN-SITU CAD
WEDGE OVER THE PIEDMONT. HIGHS THURSDAY AND FRIDAY RANGE FROM THE
MID/UPPER 50S NW...TO THE LOW/MID 70S FAR SE IN CLOSER PROXIMITY TO
THE FRONTAL BOUNDARY. WARMER OVER THE PIEDMONT SAT AND SUN...WITH
HIGHS IN THE LOW/MID 60S NW TO MID 70S SE.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
COMPLICATED...PTNTLLY VERY STORMY AND HIGHLY IMPACTFUL PD INTO
THE WKND. THERE RMN UNKNOWNS ATTM. HOW DOES HURRICANE JOAQUIN
INTERACT W/ DEEP NEGATIVE/HIGHLY ANOMALOUS UPR LVL LO PRES AS IT
TRACKS THROUGH THE CSTL SE STATES FRI NGT INTO SAT? DOES THE
HURRICANE BECOME ENTRAINED/ABSORBED IN THE OVRALL PATTERN OR RMN
SEPARATE? 00Z/30 GFS/CMC AND SEVERAL GEFS MEMBERS DEPICT A MORE
WESTWARD TRACK OF THE HURRICANE...WHILE THE 00Z/30 ECMWF AND
SEVERAL GEFS MEMBERS SHOW A NE TRACK OF THE HURRICANE WELL
OFFHOSRE...WHICH DOES NOT CAST ANYMORE CLARITY ON THE POTENTIAL
EVENT.
REGARDLESS OF HOW THE SYSTEMS INTERACT...RA (MDT/HVY) A GOOD BET INTO
SUN. (THOUGH PINPOINTING LOCATION OF EXCESSIVE AMTS UNCERTAIN
ATTM). ALSO...CONCERNS WILL BE FOR DEGREE OF CSTL FLOODING...AND
HOW STRONG WNDS WILL BECOME (ESP ON THE WTRS). THE 12Z/29 ECMWF
ONLY SLOLY TRACKS THE CLOSED UPR LVL LO PRES ENE THROUGH THE RGN
SUN/MON...WHICH WOULD RESULT IN CONTD RA...WND AND CSTL FLOODING
EFFECTS. FOR NOW...BLENDED THE FCST W/ HPC AND CONT WILL DRYING
TREND FM SUN AFTN THROUGH EARLY NEXT WK (BUT THAT IS NOT A
GUARANTEE ATTM).
HI TEMPS IN THE 60S TO L70S EACH DAY. LO TEMPS IN THE 50S TO L60S
AT NGT.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
A COLD FRNT CROSSES THE AREA THIS EVENING...WITH S/SW WINDS AHEAD
OF THE FRNT SHIFTING TO N BEHIND THE FRNT TNGT. SHOWERS AND
THUNDERSTORMS ARE POPPING UP ACROSS THE AREA WITH HEAVY RAIN
POSSIBLE. THE FRNT STALLS OFFSHORE INTO THU LEADING TO
OVERRUNNING PCPN ACROSS THE REGION. WIDESPREAD IFR CAN BE EXPECTED
DURING THAT TIME FRAME...PERHAPS EXTENDING INTO FRI.
OUTLOOK...HEAVY RAIN AND RESTRICTED FLIGHT CONDITIONS ARE POSSIBLE
SATURDAY AND SUNDAY AS AN UPPER TROF LINGERS ACROSS THE AREA AND
HURRICANE JOAQUIN PSBLY AFFECTING THE REGION.
&&
.MARINE...
A COLD FRNT APPROACHES FM THE W TDA...CROSSING THE WTRS THIS
AFTN/EVENG. SCA OVER THE CSTL WTRS CONTINUES TDA WITH 5-6 FT SEAS
EXPECTED. AS THE FRNT SLIDES OFFSHORE TNGT AND STRONG HI PRES STARTS
BUILDING OVER SE CANADA...A PERIOD OF INCREASING N/NE FLOW IS
EXPECTED OVER THE MID ATLC REGION. SEVERAL HEADLINES HAVE BEEN
ISSUED TO ACCOUNT FOR THIS...INCLUDING A GALE WARNG OVER THE NRN
CSTL WTRS WHERE GUSTS UP TO 35-40 KT ARE EXPECTED AT LEAST FM LATE
THU THRU FRI. DECIDED TO RAMP UP SCA`S TO GALE WATCHES OVER THE
REMAINING CSTL WTR ZONES AND THE BAY WHERE CONFIDENCE IS NOT HI ENUF
YET FOR A 3RD-4TH PERIOD WARNG. OTWS...A SCA HAS BEEN ISSUED OVER
THE RIVERS AND SOUND. UNSETTLED MARINE CONDS WILL EXTEND PAST THE
4TH PERIOD SO MARINE HEADLINES WILL LIKELY CONTINUE THROUGH THE
WEEKEND WITH TS JOAQUIN PSBLY AFFECTING THE REGION AS WELL. AN
EXTENDED PERIOD OF HI SEAS IS EXPECTED AS WELL...OF 10-15 FT OUT
20NM FM THU NGT THRU THE WEEKEND AND LIKELY HIGHER THE CLOSER
JOAQUIN MAKES IT TO LAND.
&&
.TIDES/COASTAL FLOODING...
COASTAL FLOOD ADVISORY NOW IN EFFECT FOR THE NORTHERN NECK AS
LEWISETTA IS FORECAST TO REACH 3.4 TO 3.5 FT. WILL ALSO MAINTAIN
A COASTAL FLOOD STATEMENT FOR EAST SIDE OF CHES BAY TO INCLUDE
DORCHESTER/SOMERSET/WICOMICO FOR UPCOMING HIGH TIDE CYCLE THIS
AFTN. ELSEWHERE...WATER LEVELS GENLY REMAIN SEVERAL TENTHS OF A
FOOT BELOW MINOR FLOOD THROUGH WED.
A COLD FRONT CROSSES THE WATERS TONIGHT. FOLLOWING THIS FRONTAL
PASSAGE...NORTH TO NORTHEAST WINDS WILL INCREASE SIGNIFICANTLY.
THIS OCCURS FIRST ACRS NORTHERN AREAS...POSSIBLY DELAYED UNTIL
LATE THU/THU NIGHT ACRS THE FAR SOUTH. STILL SOME QUESTION AS TO
EXACT WIND DIRECTION (I.E NNE TO ENE)...WHICH WOULD HAVE
SIGNIFICANT CONSEQUENCES FOR THE DEGREE OF TIDAL FLOODING IN
SPECIFIC AREAS. FOR NOW HAVE SPLIT THE DIFFERENCE...WITH MINOR
FLOODING BECOMING LIKELY FOR COASTAL AREAS (ESPECIALLY FROM
WACHAPREAGUE ON NORTH BY THU AFTN). MORE SIGNIFICANT FLOODING
POSSIBLE FOR THE LOWER BAY AND ALL COASTAL AREAS BY THU EVENING
INTO FRI AND BEYOND.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...COASTAL FLOOD ADVISORY UNTIL 6 AM EDT THURSDAY FOR VAZ075-077.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM TO 7 PM EDT THURSDAY FOR ANZ633-
635>638.
GALE WATCH FROM THURSDAY MORNING THROUGH FRIDAY MORNING FOR
ANZ630>632-634-654-656.
SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 10 AM EDT
THURSDAY FOR ANZ630>632-634.
SMALL CRAFT ADVISORY UNTIL 10 AM EDT THURSDAY FOR ANZ654-656.
SMALL CRAFT ADVISORY UNTIL 7 AM EDT THURSDAY FOR ANZ650-652.
GALE WARNING FROM 7 AM THURSDAY TO 7 AM EDT FRIDAY FOR ANZ650-
652.
SMALL CRAFT ADVISORY UNTIL 7 AM EDT FRIDAY FOR ANZ658.
&&
$$
SYNOPSIS...AJZ/SAM
NEAR TERM...AJZ/SAM
SHORT TERM...AJZ/SAM
LONG TERM...ALB/DAP
AVIATION...MAS/DAP
MARINE...BMD
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1240 PM CDT WED SEP 30 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 307 AM CDT WED SEP 30 2015
TODAY AND TONIGHT...SPRINKLES SHOULD EXIT THE FCST AREA BY OR AROUND
15Z ACCORDING TO THE RAP MODEL. SOUTH WINDS KEEP MOISTURE IN PLACE
ACROSS WRN NEB TODAY AND TONIGHT WITH MIXING PROCESSES PRODUCING
PARTLY CLOUDY SKIES. STRATUS SHOULD RETURN TONIGHT ACCORDING TO THE
SREF MODEL.
HIGHS IN THE 60S ARE IN PLACE TODAY WITH COOL AIR RECYCLING
NORTHWARD. LOWS IN THE 50S FOLLOW TONIGHT WITH THE EXPECTED CLOUD
COVER.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 307 AM CDT WED SEP 30 2015
AN UPPER LEVEL BLOCKING PATTERN EXPECTED TO PERSIST THROUGH THE
WEEKEND INTO EARLY NEXT WEEK. THIS WILL CONSIST OF A LONG WAVE
TROUGH ACROSS THE WESTERN CONUS...AN UPPER RIDGE ACROSS THE GREAT
LAKES AND EASTERN CANADA...AND A CUT OFF UPPER LEVEL LOW ACROSS
THE SOUTHEAST CONUS. EXPECT A SYSTEM TO EJECT EAST FROM THE
WESTERN CONUS LONG WAVE TROUGH INTO THE CENTRAL AND NORTHERN
PLAINS FRIDAY INTO SATURDAY...WITH THE ENTIRE LONG WAVE TROUGH TO
TRANSLATE EAST INTO THE CENTRAL AND NORTHERN PLAINS EARLY NEXT
WEEK AS THE UPPER PATTERN FINALLY BECOMES A BIT MORE PROGRESSIVE.
AS MENTIONED A SHORTWAVE TROUGH WILL EJECT EAST INTO THE REGION
FRIDAY INTO SATURDAY...THEN WEAKEN AND DISSIPATE SUNDAY AS IT
ENCOUNTERS THE STRONG UPPER LEVEL RIDGING ANCHORED ACROSS THE
GREAT LAKES/EASTERN CANADA. MODELS CONTINUE TO TREND SLOWER WITH
THIS SYSTEM...AND HAVE DELAYED THE ONSET OF RAIN UNTIL THURSDAY
NIGHT ACROSS NORTHWEST NEBRASKA. EXPECT RAIN TO SPREAD EAST
FRIDAY...WITH THE HEAVIEST MOST CONCENTRATED PERIOD OF RAIN TO
FALL FRIDAY NIGHT. DRY AIR IN THE LOWER LEVELS OF THE ATMOSPHERE
WILL BE CIRCULATING INTO EASTERN AND CENTRAL NEBRASKA OFF THE HIGH
ACROSS THE GREAT LAKES AND EASTERN CANADA. THIS WILL DELAY THE
RAIN UNTIL POSSIBLY FRIDAY NIGHT FOR AREAS AROUND
ONEILL...BARTLETT AND EWING.
THIS DRY AIR MAKES FOR A DIFFICULT FORECAST IN REGARDS TO STRATUS
CLOUD COVER. IT APPEARS THAT ENOUGH OF THE DRY AIR WILL MIX INTO
WESTERN NEBRASKA...AND HELP TO THIN AND BREAK UP THE STRATUS CLOUD
DECK THURSDAY AFTERNOON. FARTHER EAST...LITTLE IN THE WAY OF
STRATUS CLOUD COVER IS EXPECTED ACROSS CENTRAL AND NORTH CENTRAL
NEBRASKA WHERE THE DRY AIR LAYER WILL BE DEEPER. WITH THE ARRIVAL
OF THE SHORTWAVE TROUGH FRIDAY...MIDDLE AND HIGH CLOUDS WILL
DEVELOP AND OVERSPREAD THE AREA. IN ADDITION...THE LOW LEVELS WILL
REMAIN MOIST ENOUGH THAT A LOW CLOUD STRATUS DECK SHOULD REMAIN IN
PLACE THROUGH THE DAY ACROSS FAR WESTERN NEBRASKA AND THE
PANHANDLE. STILL EXPECTING THE DRIER AIR TO KEEP STRATUS TO A
MINIMUM FARTHER EAST. BY FRIDAY NIGHT INTO SATURDAY...ALL AREAS
WILL SEE THE LOWER LEVELS MOISTEN WITH A SOLID OVERCAST.
FOR THURSDAY AND FRIDAY...EXPECT THE COOLER HIGH TEMPERATURES TO
RESIDE ALONG AND WEST OF HIGHWAY 83 WHERE MORE CLOUD COVER IS
EXPECTED. THEN ON SATURDAY EXPECT A RAW DAY ACROSS ALL OF THE
AREA...WITH HIGHS BARELY REACHING INTO THE 50S DUE TO CLOUDS AND
COOL EAST/SOUTHEAST LOW LEVEL FLOW.
EARLY NEXT WEEK THE LONG WAVE TROUGH MIGRATES EAST BUT DAMPENS AS IT
MOVES INTO THE CENTRAL AND NORTHERN PLAINS. FOR NOW AT LEAST A LOW
CHANCE POP FOR SHOWERS SEEMS WARRANTED WITH THE ARRIVAL OF THE
TROUGH.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1231 PM CDT WED SEP 30 2015
LOW CIG STRATUS CONTINUES TO HOLD STRONG OVER MUCH OF WESTERN
NEBRASKA AS OF EARLY WEDNESDAY AFTERNOON INCLUDING
KLBF...KVTN...KIML...AND KOGA. FLIGHT RESTRICTIONS BECOME MORE
SIGNIFICANT WITH WESTWARD PROGRESSION AS KIML AND KOGA HAVE
REPORTED SUB-1KFT CIGS WITH VISBYS NEAR 3SM FOR MOST OF THE
DAY. THESE CONDITIONS ARE FORECAST TO PERSIST THROUGH THE
AFTERNOON AND INTO THIS EVENING. FURTHER EAST CIGS HAVE IMPROVED
TO MVFR/VFR AT KVTN AND KLBF. CLOUD COVER ERODES INTO CENTRAL
NEBRASKA.
THE CONTINUATION/REDEVELOPMENT OF LOW STRATUS IS LIKELY ONCE AGAIN
TONIGHT AND INTO THURSDAY MORNING. CURRENT MODEL GUIDANCE IS IN
STRONG AGREEMENT WITH IFR CIGS AT BOTH KLBF AND KVTN...HOWEVER
CONFIDENCE WANES WITH EASTWARD EXTENT AND IT REMAINS UNCLEAR JUST
HOW FAR EAST THE STRATUS DECK WILL ADVANCE. NOT A FAVORABLE SETUP
FOR THE DEVELOPMENT OF FOG BUT MINOR VISBY RESTRICTIONS WILL BE
POSSIBLE FURTHER WEST TOWARD THE HIGHER TERRAIN NEAR THE NEBRASKA
PANHANDLE WHERE CIGS WILL BE AT OR BELOW 1K FEET.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1214 PM CDT WED SEP 30 2015
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 313 AM CDT WED SEP 30 2015
LATEST WATER VAPOR IMAGERY AND RAP 500MB HEIGHT ANALYSIS SHOWS LARGE
RIDGE OF HIGH PRESSURE EXTENDING FROM NORTHWESTERN MEXICO INTO
BRITISH COLUMBIA/ALBERTA. DOWNSTREAM...A LARGE TROUGH EXTENDS
FROM HUDSON`S BAY TO EASTERN TEXAS PUTTING OUR REGION IN MODEST
NORTHWESTERLY FLOW. A WEAK SHORTWAVE OVER SOUTHEAST SOUTH DAKOTA
HAS PROVEN TO BE ENOUGH FORCING TO SPAWN A FEW RADAR RETURNS
ACROSS SOUTHEAST SOUTH DAKOTA AND NORTHEAST NEBRASKA. NOT
ANTICIPATING MUCH...IF ANYTHING...TO REACH THE GROUND AS OBS
INDICATE ALL MID CLOUDS. LOW LEVELS WILL REMAIN QUITE DRY WITH SFC
HIGH PRESSURE ANCHORED FROM QUEBEC SOUTHWESTWARD TO THE GREAT
PLAINS.
THE ABOVE MENTIONED MID LEVEL SHORTWAVE WILL CONTINUE TO DROP
SOUTHEAST INTO MISSOURI EARLY TODAY. MID CLOUDS SHOULD DIMINISH
LATER THIS MORNING BUT HIGHS WILL REMAIN SLIGHTLY BELOW NORMAL IN
THE MID TO UPPER 60S.
THE UPPER RIDGE AXIS WILL SHIFT EAST TOWARD THE FORECAST AREA BY
THE WEEKEND AHEAD OF A LARGE APPROACHING UPPER TROUGH.
TEMPERATURES WILL REMAIN COOLER THAN NORMAL FOR THIS TIME OF THE
YEAR WITH CONTINUED EASTERLY LOW LEVEL FLOW.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 313 AM CDT WED SEP 30 2015
PCPN CHANCES BEGIN TO INCREASE ACROSS WESTERN AND CENTRAL NEBRASKA
FRIDAY NIGHT IN ADVANCE OF APPROACHING UPPER TROUGH. OVERALL
TREND HAS BEEN TO LOWER POPS IN OUR AREA AS BEST FORCING
ASSOCIATED WITH THE UPPER TROUGH REMAINS TO OUR WEST AND NORTH.
DRY AIR TO OUR EAST WILL BE PROBLEMATIC AND SHOULD KEEP CONDITIONS
MOSTLY DRY ACROSS THE EASTERN CWA.
THE BASE OF THE WESTERN UPPER TROUGH WILL ROUND THE FOUR CORNERS
REGION LATE IN THE EXTENDED. THIS COULD BRING PCPN TO THE AREA BY
EARLY TO MID NEXT WEEK HOWEVER MANY FORECAST UNCERTAINTIES
REMAIN.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1214 PM CDT WED SEP 30 2015
VFR CONDITIONS EXPECTED THRU THE FCST PD.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...KERN
LONG TERM...KERN
AVIATION...DEE
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
140 PM EDT WED SEP 30 2015
.SYNOPSIS...
A QUASI-STATIONARY FRONT EXTENDING FROM NORTHEAST TO SOUTHWEST
ACROSS SOUTH-CENTRAL VERMONT INTO CENTRAL NEW YORK WILL CONTINUE
TO PROVIDE A FOCUS FOR HEAVY RAINFALL THROUGH MID AFTERNOON
TODAY...AND WILL BRING THE PROSPECT OF MINOR TO MODERATE FLOODING
ON RIVERS AND STREAMS TODAY INTO THIS EVENING. A DEVELOPING WAVE
OF LOW PRESSURE ALONG THE FRONT WILL SHIFT EAST OF THE REGION LATE
THIS AFTERNOON...FINALLY ALLOWING THE FRONT TO PUSH SOUTH OF
VERMONT USHERING IN A DRIER AND COOLER AIR MASS FOR TONIGHT.
DESPITE SOME CONTINUED HIGH LEVEL CLOUDINESS...STRONG HIGH
PRESSURE ANCHORED ACROSS QUEBEC AND ONTARIO WILL BRING A PERIOD OF
DRY WEATHER THURSDAY THROUGH SATURDAY...WITH NEAR SEASONABLE
TEMPERATURES.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
AS OF 951 AM EDT WEDNESDAY...NO SIGNIFICANT CHANGES TO THE
FORECAST. FLOOD WATCH CONTINUES IN EFFECT THROUGH 06Z THURSDAY.
RIVERS ARE RISING AND WATCHING A FEW LIKE OTTER CREEK AT RUTLAND
AND MISSISQUOI AT NORTH TROY BUT AT THE MOMENT IT LOOKS LIKE WE
MIGHT DODGE ANY SIGNIFICANT FLOODING ON THE RIVERS.
FOR THE WEATHER...BLENDED IN SOME OF THE HRRR SIMULATED RADAR
TRENDS WHICH SHOWS DRY SLOT NOW MOVING TOWARD SOUTHERN VERMONT
WITH HEAVIEST BAND CENTRAL AND NORTHERN VT/NY THIS MORNING.
STILL EXPECTING UP TO ANOTHER INCH OF RAIN OR SO IN FROM BTV
SOUTH AND EAST WHERE RAIN WILL BE MAINLY MODERATE BUT LOCALLY
HEAVY FOR A FEW MORE HOURS.
RAIN WILL LIGHTEN UP AND MOVE OUT GRADUALLY THIS AFTERNOON THOUGH
THERE MAY STILL BE SOME VERY LIGHT RAIN OR DRIZZLE RIGHT UNTIL
SUNSET FOR NORTHEAST VERMONT AND THE MOUNTAINS.
LITTLE CHANGE IN TEMPS FOR THE REST OF THE DAY...A COOL ONE WITH
TEMPS MOSTLY IN THE 50S AND SOME UPPER 40S IN THE HIGHER TERRAIN
WITH FRESH NORTHERLY BREEZE.
HAVE RECENTLY RECEIVED OBSERVED STORM TOTAL RAINFALL REPORTS
AROUND 4-4.5" IN NORTH UNDERHILL...LINCOLN AND WATERVILLE VT. WE
WILL ISSUE A PUBLIC INFORMATION STATEMENT SHORTLY AFTER 10 AM
WITH MORE RAINFALL AMOUNTS.
PREVIOUS DISCUSSION FOLLOWS...
WIDESPREAD MODERATE TO HEAVY RAIN IN PLACE ACROSS ALL OF THE
NORTH COUNTRY EXCEPT ST. LAWRENCE VALLEY THIS MORNING...AND WILL
CONTINUE TO BE THE CASE THROUGH 18-20Z TODAY. SURFACE FRONTAL
BNDRY HAS BECOME QUASI- STATIONARY ACROSS SOUTH- CENTRAL VERMONT
AND THE SRN ADIRONDACKS AT 01Z...AND WILL CONTINUE TO PROVIDE A
FOCUS FOR THE HEAVIEST RAINFALL DURING THE NEXT 6-9 HRS. WE HAVE
SEVERAL DYNAMIC FEATURES IN PLAY THRU MID- AFTN. A STRENGTHENING
FRONTAL WAVE CONTINUES TO DEVELOP ACROSS WRN PA EARLY THIS
MORNING...AND WILL TRACK ENEWD ALONG THE FRONTAL ZONE REACHING
CENTRAL VT MID- LATE MORNING. THIS FEATURE ALSO STRENGTHENS WITHIN
RIGHT ENTRANCE REGION OF 250MB JET ACROSS ERN QUEBEC. WE ALSO
HAVE A SFC MESOLOW ACROSS NERN PA/NWRN NJ EMBEDDED IN TROPICAL
REGIME WITH LOW 70S DEWPOINTS AND PW VALUES IN EXCESS OF 2" (2.22"
OBSERVED AT 00Z WAL SOUNDING). HAVE SEEN RAINFALL RATES OF
0.50-0.60" PER HOUR WITH HIGHER REFLECTIVITY AREA STREAMING NWD
FROM NEW YORK CITY VCNTY. AS FRONTAL WAVE SHIFTS ENEWD...SURGE OF
45-55KT SOUTHERLY FLOW WILL ADVECT TROPICAL MOISTURE INTO THE
FRONTAL BNDRY ACROSS CENTRAL/S-CENTRAL VT DURING 12-18Z
PERIOD...WHICH CONTINUES CONCERN FOR FLOODING. ALSO NOTING STRONG
850-700MB FRONTOGENETIC FORCING 12-18Z...AND THIS MESOSCALE
CIRCULATION WILL AUGMENT SYNOPTIC ASCENT AND ENHANCE RAINFALL
RATES. COULD SEE AN ADDITIONAL 2-3" OF RAINFALL ACROSS
CENTRAL/S-CENTRAL VT...WITH CONTINUED PROSPECTS FOR MINOR TO
MODERATE FLOODING...ESPECIALLY ON SMALLER RIVERS AND STREAMS.
RUNOFF COULD CONTINUE TO RESULT IN RIVER RISES THRU THE FIRST HALF
OF TONIGHT. WE WILL CONTINUE TO CLOSELY MONITOR PRECIPITATION AND
HYDRO TRENDS THROUGHOUT THE DAY.
OTHERWISE...WILL SEE LOW-LEVEL CAA CONTINUE TO WORK IN FROM THE
NORTH AND WEST. CLOUDS/PRECIPITATION AND NORTH FLOW WILL KEEP TEMPS
IN THE 50S ACROSS MUCH OF THE NRN HALF OF THE FORECAST AREA...WHILE
READINGS STAY IN THE MID 60S ACROSS S-CENTRAL VT UNTIL FRONTAL WAVE
PASSES LATE THIS AFTN...AND FRONT SURGES SOUTHWARD AND OUT OF THE
REGION. IT APPEARS MOST OF THE RAIN SHOULD EXIT EASTERN VT BY 21Z OR
SO...AND WILL SHOW DECREASING POPS ACCORDINGLY FROM WEST TO EAST
DURING THE LATE AFTERNOON HRS. SOME CLEARING SHOULD WORK INTO NRN NY
TOWARD SUNSET...BUT UPPER CIRRUS CANOPY SHOULD REMAIN IN PLACE FOR
MOST SECTIONS HEADING THRU THIS EVENING.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH FRIDAY/...
AS OF 349 AM EDT WEDNESDAY...MUCH QUIETER STRETCH OF WEATHER
ANTICIPATED AS FRONTAL ZONE SHIFTS OFFSHORE SOUTHEAST OF NEW
ENGLAND AND STRONG SURFACE ANTICYCLONE ANCHORED ACROSS ONTARIO AND
QUEBEC BECOMES OUR CONTROLLING WEATHER FEATURE. HAVE SHOWN DRY
CONDITIONS THROUGHOUT. WINDS WILL CONTINUE MODERATELY STRONG FROM
THE NORTH DURING THE PERIOD (NORTH 15-20 MPH DURING THE DAYLIGHT
HRS THURSDAY) BRINGING COOLER TEMPERATURES WITH HIGHS IN THE MID-
UPR 50S FOR THURSDAY....AND GENERALLY MID 50S ON FRIDAY. MAY SEE
SOME PATCHY FROST THURSDAY NIGHT ACROSS SHELTERED SECTIONS OF NRN
NY...THOUGH CONTINUED SWLY UPR TROPOSPHERIC FLOW SHOULD MAINTAIN
SOME CIRRUS CLOUDS AND MITIGATE EXTENT OF RADIATIONAL COOLING.
ALSO COULD SEE WINDS CONTINUE ABOVE 5 MPH DURING THE NIGHTTIME
HRS...WHICH WOULD NOT BE CONDUCIVE FOR FROST FORMATION. HAVE LEFT
OUT OF THE OFFICIAL FORECAST FOR NOW. HAVE INDICATED LOW
TEMPERATURES UPR 30S TO LOW 40S TONIGHT AND AGAIN THURSDAY
NIGHT...BUT LOCALLY NEAR FREEZING IN THE COLDER SPOTS WITHIN THE
NRN ADIRONDACK REGION.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 349 AM EDT WEDNESDAY...SURFACE HIGH PRESSURE WILL KEEP
FRONTAL BOUNDARY JUST TO OUR SOUTH FRIDAY NIGHT THROUGH MOST OF
SATURDAY...BUT POPS WILL BE INCREASING AS THE HIGH BEGINS TO
WEAKEN LATE SATURDAY INTO EARLY SUNDAY. AS THIS IS
HAPPENING...TROPICAL CYCLONE JOAQUIN WILL MOVE NORTHWARD OFF THE
SOUTH CAROLINA COAST BY SATURDAY. MODEL GUIDANCE THEN DIVERGES
WITH REGARDS TO MID-UPPER LEVEL PATTERN AND TRACK/EVOLUTION OF
JOAQUIN. SEVERAL UPPER LEVEL CLOSED LOWS AND HIGH PRESSURE RIDGES
WILL GIVE THE MODELS DIFFICULTY IN RESOLVING TRACKS.
ECMWF CONTINUES TO KEEP JOAQUIN OFF THE COAST...WITH SLIGHT TREND
WEST WITH REGARDS TO TRACK. A MIDLEVEL SHORTWAVE COULD PRODUCE SOME
SHOWERS SUNDAY. OTHERWISE A MOSTLY DRY FORECAST BUT WITH JOAQUIN
TRACKING INTO A MIDLEVEL RIDGE HAVE OPTED TO LEAN TOWARDS THE GFS,
WHICH SHOWS JOAQUIN INTERACTING WITH CLOSED 500MB LOW OVER THE
SOUTHEASTERN STATES. THIS LOW WILL PULL JOAQUIN ONTO THE COAST
AROUND DELMARVA AND COMBINE WITH THE 500MB LOW... RESULTING IN
PRECIPITATION SPREADING ACROSS THE NORTH COUNTRY FROM THE SOUTH ON
SUNDAY ACCOMPANIED BY STRONG LOW LEVEL WINDS. THE LOW WILL BE SLOW
TO PROGRESS NORTHWARD PROVIDING SEVERAL DAYS OF POTENTIAL RAINFALL.
WILL HAVE TO MONITOR EVOLVING SYSTEMS AS MOISTURE FROM JOAQUIN AND
RESULTING RAINFALL COULD INCREASE THE POTENTIAL FOR MORE RIVER RISES
LATE IN THE WEEKEND. SINCE THERE ARE STILL SOME TIMING ISSUES...HAVE
LEFT PRECIPITATION CHANCES IN THE EXTENDED GENERALLY IN THE CHANCE
CATEGORY. BELOW NORMAL TEMPERATURES WILL TREND WARMER TO NEAR
SEASONAL NORMALS BY EARLY NEXT WEEK.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
THROUGH 18Z THURSDAY...RAIN CONTINUES TO SLOWLY SHIFT NORTHEAST
OUT OF THE BTV AIRSPACE THIS AFTERNOON WITH NO RESTRICTIONS IN
VISIBILITY BELOW 6SM NOTED ON SURFACE OBS AND NOT EXPECTING ANY
FOR THE REMAINDER OF THE TAF PERIOD. CURRENT MIX OF IFR/MVFR WILL
PERSIST OVER THE NEXT 3-6 HOURS, SLOWLY LIFTING TO MVFR/VFR AFTER
00Z AND EVENTUALLY VFR AT ALL SITES AFTER 06Z TONIGHT. MODERATE WINDS
FROM THE NORTH CONTINUE THIS AFTERNOON WITH GUSTS IN THE 20-25KT
RANGE, BUT WILL LOWER TO JUST SUSTAINED WINDS OF 10-15KTS FOR THE
OVERNIGHT HOURS AND INTO THURSDAY.
OUTLOOK 18Z THURSDAY THROUGH MONDAY...
18Z THU - 00Z MON...VFR. VLIFR/LIFR FOG POSSIBLE AT KSLK/KMPV
05-13Z SUNDAY.
00Z MON - 00Z TUE...VFR TRENDING TO MVFR/IFR IN RAIN AS LOW
PRESSURE MOVES UP THE EASTERN SEABOARD.
&&
.MARINE...
AS OF 355 AM EDT WEDNESDAY...A LAKE WIND ADVISORY CONTINUES IN
EFFECT UNTIL FURTHER NOTICE FOR LAKE CHAMPLAIN. THE COLD FRONT HAS
PUSHED SOUTH OF LAKE CHAMPLAIN...AND WILL CONTINUE TO SEE NORTH
WINDS 18-25 KTS THIS MORNING...INCREASING TO 20-30 KTS THIS
AFTERNOON AND EVENING. LAKE WIND ADVISORY CRITERIA WILL LIKELY BE
MET THROUGH THURSDAY...WITH WINDS REMAINING FROM THE NORTH. WAVES
WILL GENERALLY BE IN THE 2 TO 4 FT RANGE, PARTICULARLY HIGHEST IN
BAYS AND INLETS ON THE SOUTHERN END OF LAKE CHAMPLAIN. WAVES MAY
BRIEFLY REACH 3 TO 5 FT TONIGHT.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...FLOOD WATCH THROUGH LATE TONIGHT FOR VTZ007>012-018-019.
NY...FLOOD WATCH THROUGH LATE TONIGHT FOR NYZ034-035.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS/SISSON
SHORT TERM...BANACOS
LONG TERM...KGM
AVIATION...LAHIFF
MARINE...LOCONTO
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1236 PM CDT WED SEP 30 2015
.UPDATE...
ISSUED AT 1219 PM CDT WED SEP 30 2015
NO MAJOR UPDATES ARE NEEDED WITH THE FORECAST AT THIS TIME. JUST
TWEAKED PRECIPITATION CHANCES...CLOUD COVER...AND WINDS THIS
AFTERNOON AND EVENING BASED ON THE LATEST HIGH RESOLUTION MODEL
RUNS AND OBSERVATIONAL TRENDS. AMPLIFYING SHORTWAVE TROUGH
LOCATED OVER SOUTHERN SASKATCHEWAN WILL CONTINUE TO SLIDE
SOUTHEAST INTO OUR AREA THIS AFTERNOON BEFORE CLOSING OFF
OVERNIGHT. LATEST THINKING IS THAT SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS WILL START TO DEVELOP IN NORTH CENTRAL AND
NORTHEASTERN NORTH DAKOTA BY 21-22Z AND SPREAD SOUTH SOUTHWEST
THROUGH THE NIGHT AND INTO THURSDAY MORNING.
UPDATE ISSUED AT 901 AM CDT WED SEP 30 2015
CUT DOWN ON CLOUD COVER JUST A LITTLE BIT BASED ON LATEST
SATELLITE IMAGERY AND HIGH RESOLUTION MODEL TRENDS. DECIDED TO
BUMP UP WINDS SLIGHTLY LATER THIS AFTERNOON IN THE EAST BASED ON
RAP BUFKIT SOUNDINGS AT KJMS. ALSO DELAYED ONSET OF ISOLATED
PRECIPITATION CHANCES UNTIL 21Z IN THE NORTH CENTRAL AND NORTHEAST
BASED ON LATEST RAP AND NAM RUNS. OTHER THAN THAT...FORECAST LOOKS
ON TRACK AND NO OTHER MAJOR UPDATES WERE NEEDED.
UPDATE ISSUED AT 626 AM CDT WED SEP 30 2015
HIGH PRESSURE OVER THE NORTHERN GREAT LAKES REGION...AND LOW
PRESSURE OVER EASTERN MONTANA IS PRODUCING A MODERATE SOUTHERLY
FLOW ACROSS WESTERN AND CENTRAL NORTH DAKOTA THIS MORNING.
TEMPERATURES REMAIN MAINLY IN THE UPPER 40S TO MIDDLE 50S AND HAVE
NOT DROPPED AS LOW AS FORECAST. SOME AREAS COULD DROP A COUPLE
MORE DEGREES BUT IN GENERAL THINK WE HAVE SEEN OVERNIGHT LOWS.
WILL ADJUST TEMPERATURES TO REFLECT THIS. MADE SOME CHANGES TO SKY
COVER BASED ON LATEST SATELLITE IMAGERY. A FEW SHOWERS SHOWING UP
ON RADAR OVER THE JAMES RIVER VALLEY TRACKING NORTHEAST. ADDED A
SLIGHT CHANCE OF AN EARLY MORNING SHOWER HERE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 322 AM CDT WED SEP 30 2015
CURRENTLY...A LARGE SURFACE HIGH WAS CENTERED OVER THE GREAT LAKES
AREA...WITH A LOW PRESSURE TROUGH IN THE LEE OF THE ROCKIES. AT
UPPER LEVELS...A LARGE LOW OVER HUDSON BAY AND A RIDGE OVER THE
ROCKIES RESULTED IN SLIGHT NORTHWEST FLOW ALOFT OVER NORTH DAKOTA.
AN UPPER LEVEL SHORTWAVE WAS NOTED OVER SOUTH CENTRAL SASKATCHEWAN
IN THE LATEST SATELLITE WATER VAPOR LOOP.
SURFACE WINDS ACROSS THE REGION WERE SOUTHERLY...WITH SOUTHERLY
WINDS AT H925 AT 30 KNOTS OVER CENTRAL AND EASTERN NORTH DAKOTA.
THIS LOW LEVEL JET EXTENDS WELL NORTHWARD INTO MANITOBA. IT IS
LIKELY ASSOCIATED WITH A SHOWER THAT DEVELOPED NEAR THE TURTLE
MOUNTAINS...AND HAS SINCE MOVED NORTHEASTWARD INTO MANITOBA. THIS
INDICATES INSTABILITY IS GREAT ENOUGH FOR SHOWERS. THIS LOW LEVEL
JET IS FORECAST TO REMAIN OVER THE DAKOTAS TODAY AND
TONIGHT...HELPING TO KEEP LOW AND MID-LEVEL MOISTURE MOVING
NORTHWARD FROM THE CENTRAL PLAINS. MEANWHILE THE AFOREMENTIONED
SHORTWAVE OVER SOUTHERN SASKATCHEWAN IS PROGGED TO REACH THE
SOUTHERN BORDER OF SASK/MAN THIS AFTERNOON...THEN STALL THERE
TONIGHT. THE INCREASING CLOUDS/MOISTURE AND SUPPORT FROM THE UPPER
LEVEL SHORTWAVE SHOULD PROVIDE ENOUGH INSTABILITY FOR SHOWERS THIS
MORNING...AND THUNDERSTORMS THIS AFTERNOON AND TONIGHT. BEST CHANCES
THIS AFTERNOON LOOK TO BE OVER NORTH CENTRAL NORTH DAKOTA. THE PUSH
OF DRY AIR FROM THE WEST...ON THE WEST SIDE OF THE LOW LEVEL
JET...THIS AFTERNOON AND TONIGHT WILL EXPAND THE AREA OF POTENTIAL
SHOWERS/THUNDER OVER MUCH OF WESTERN AND CENTRAL NORTH DAKOTA
TONIGHT AND CHANCES OF PRECIPITATION INCREASE. GIVEN FAIRLY LOW
BOUNDARY LAYER CAPE OF 250-500 J/KG MOST AREA...WILL OPT FOR CHANCES
OF SHOWERS BUT WITH ONLY ISOLATED THUNDERSTORMS EMBEDDED IN THE
SHOWERS.
WITH DAYTIME HEATING THE SURFACE LAYER SHOULD LINK WITH THE LOW
LEVEL JET...AND BRING WINDY CONDITIONS TO CENTRAL NORTH DAKOTA.
LOOKING AT 20 TO 25 MPH SUSTAINED WINDS WITH GUSTS TO AROUND 30 MPH.
HIGHS TODAY SHOULD RANGE FROM THE UPPER 60S OVER THE JAMES RIVER
BASIN...TO THE UPPER 70S SOUTHWEST. LOWS TONIGHT IN THE 40S.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 322 AM CDT WED SEP 30 2015
A COMPLEX UPPER LEVEL PATTERN HIGHLIGHTS THE LONG TERM PERIOD OVER
THE UPCOMING WEEKEND.
ON THURSDAY...A SHORTWAVE TROUGH CURRENTLY TRACKING THROUGH
SASKATCHEWAN RETROGRADES WESTWARD FROM MANITOBA BACK INTO
SASKATCHEWAN AS A REX BLOCK DEVELOPS WITH THE BLOCKING HIGH OVER
NORTHERN SASKATCHEWAN AND MANITOBA...AND THE UPPER LOW DEVELOPING
FROM THE AFOREMENTIONED SHORTWAVE. THE UPPER LOW EVENTUALLY GETS
PULLED NORTHWARD...OUT OF THE REGION...BUT THERE SHOULD BE ENOUGH
INSTABILITY ASSOCIATED WITH THE UPPER LOW TO PRODUCE SCATTERED
SHOWERS MAINLY ACROSS CENTRAL NORTH DAKOTA ON THURSDAY.
THURSDAY NIGHT THROUGH SATURDAY...THERE COULD BE A FEW REMAINING
SHOWERS INTO THURSDAY EVENING ASSOCIATED WITH THE CANADIAN LOW...BUT
BY THIS TIME THE FOCUS SHIFTS WESTWARD AS ANOTHER UPPER LOW TRACKS
ACROSS THE NORTHERN AND CENTRAL ROCKIES. THE LOW BECOMES NEARLY
STATIONARY OVER THE NORTHERN ROCKIES AND NORTHERN HIGH PLAINS AS
ANOTHER UPPER LOW DIGS SOUTH ALONG THE WEST COAST. SHORTWAVE
ENERGY LIFTING THROUGH THE BROAD UPPER CIRCULATION IN COMBINATION
WITH AN INCREASING WARM ADVECTION PATTERN OVER THE WESTERN DAKOTAS
WILL RESULT IN A BROADER....MORE EXPANSIVE AREA OF SHOWERS FRIDAY
THROUGH SATURDAY. THE RESULT WILL BE FOR LIKELY POPS WEST AND A
CHANCE IN CENTRAL NORTH DAKOTA FRIDAY/FRIDAY NIGHT...AND HIGH
CHANCE POPS REMAINING OVER THE WEST SATURDAY. THE SHOWERS
GRADUALLY DWINDLE SATURDAY NIGHT INTO SUNDAY.
SIGNIFICANT EC/GFS MODEL DIFFERENCES DEVELOP BEYOND SUNDAY IN THE
HANDLING OF THE SECOND WEST COAST UPPER LOW. AND THE AMOUNT OF
INTERACTION BETWEEN THIS LOW AND THE NORTHERN STREAM JET.
VERY COOL TEMPERATURES FRIDAY THROUGH SUNDAY WITH SIGNIFICANT
CLOUD COVER AND SHOWERS. HIGHS FORECAST IN THE MID TO UPPER 50S
TO LOWER 60S ACROSS WESTERN AND CENTRAL NORTH DAKOTA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1219 PM CDT WED SEP 30 2015
LOW CLOUDS OVER THE SOUTHWEST CONTINUE TO ERODE WITH EARLY
AFTERNOON WARMING...WHILE CLOUDS IN THE EAST WILL SLOWLY MOVE OUT
OF THE FORECAST AREA. A COLD FRONT WILL MOVE THROUGH THE AREA
OVERNIGHT...WITH SHOWERS POSSIBLE IN THE VICINITY OF
KBIS/KMOT/KJMS BY EARLY THURSDAY MORNING. AHEAD OF THIS
FRONT...EXPECT GUSTY WINDS OVER PARTS OF CENTRAL AND EASTERN
NORTH DAKOTA. THE STRONGEST WINDS WILL RESIDE IN THE JAMES RIVER
VALLEY...WHERE GUSTS OF UP TO 32 KNOTS WILL BE POSSIBLE THROUGH
THE AFTERNOON AND EARLY EVENING. SOME FOG WILL BE POSSIBLE IN THE
VICINITY OF KDIK AFTER 09Z THURSDAY WITH MVFR
CEILINGS/VISIBILITIES LIKELY. OTHERWISE...VFR CONDITIONS WILL
PREVAIL OVER ALL OTHER SITES THROUGH THE PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ZH
SHORT TERM...JV
LONG TERM...TWH
AVIATION...ZH
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
356 PM EDT WED SEP 30 2015
.SYNOPSIS...
AN AREA OF LOW PRESSURE MOVING INTO NEW ENGLAND WILL BE FOLLOWED
BY WEAK HIGH PRESSURE. ANOTHER SIGNIFICANT RAIN EVENT IS POSSIBLE
FRIDAY INTO THE UPCOMING WEEKEND AS A DEEPENING UPPER LOW OVER THE
SOUTHERN APPALACHIANS DRAWS MOISTURE INLAND FROM THE WESTERN
ATLANTIC.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
THE SURFACE LOW AS OF 1PM IS AROUND PORTSMOUTH NH WITH A
FRESHENING NORTHERLY FLOW SETTING UP OVER MUCH OF THE LOCAL AREA
IN ITS WAKE. RADAR SHOWS LIGHT RETURNS IN THE REMAINS OF THE
DEFORMATION ZONE THAT EXTENDS FROM ABOUT TN UP INTO NRN NEW
ENGLAND.
THE FRESHENING NORTHERLY FLOW WILL BRING A PERIOD OF DRYER CONDITIONS
TO THE REGION WITH THE HRRR SUPPORTING THE IDEA OF JUST SOME
SCATTERED LIGHT SHOWERS GRADUALLY DIMINISHING BY NIGHTFALL.
THE TIGHTENING SFC PRESSURE GRADIENT WILL SUPPORT WINDS OF 10-15
MPH WITH GUSTS INTO THE LOW/MID 20S THIS AFTERNOON AND EVENING.
CLOUDS WILL HANG TOUGH OVERNIGHT AS THE BAROCLINIC ZONE ASSOCIATED
WITH THE COLD FRONT DOESN`T STRAY TOO FAR OFF TO OUR SOUTH AND
EAST. I DID HAVE A SMALL CHANCE OF A SHOWER OVER THE FAR SERN
ZONES...BUT FOR THE UPDATE I CHOSE TO KEEP IT DRY...BUT SHOWERS
WILL NOT BE TOO FAR AWAY OVER MD AND NJ.
OVERNIGHT LOWS WILL RANGE FROM AROUND 40 OVER THE NORTHERN
MOUNTAINS TO THE MID 50S OVER THE SOUTHEAST.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
THURSDAY WILL REMAIN CLOUDY OVER MOST OF THE AREA...WITH THE BEST
CHANCE OF SOME SUNSHINE BEING OVER THE NW ZONES FOR THE AFTERNOON
HOURS. OVER SERN PA...GUIDANCE DIFFERS AS TO HOW FAST AND HOW FAR
NORTH TO BRING SOME LIGHT RAIN DURING THE AFTERNOON. I LEANED
CLOSER TO A BLENDED MOS SOLUTION WHICH HAS A CHANCE OF RAIN FOR
ABOUT THE SERN 1/3 OF THE COUNTY WARNING AREA.
HIGHS THURSDAY LOOK LIKE THEY WILL AVERAGE A FEW DEGREES EITHER
SIDE OF 60...COOLER NORTH...MILDER SOUTH.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
MAIN CHANGE WAS TO EDGE POPS UP SOME FRIDAY INTO SUNDAY AND
ALSO ADDED CHC OF RAIN INTO MONDAY.
ALSO LOWER TEMPS SOME AND UP WINDS.
MODELS SHOW COLD FRONT BACKING TO THE WEST BY LATE SAT.
THIS WOULD BRING SOME HEAVY RAIN BACK INTO THE AREA. WHILE
THE HEAVIST RAIN COULD MOVE WEST OF OUR AREA BY LATE SAT OR
EARLY SUNDAY...STILL LOOKING AT A STRONG EAST TO SE FLOW OF
AIR OFF THE WESTERN ATLANTIC WITH COLD TEMPERATURES...HEAVY
RAIN ETC.
ALSO STILL SOME TIME TO DETERMINE ANY POTENTIAL INTERACTION
WITH WITH THE TROPICS.
EARLIER DISCUSSION BELOW.
STALLED OUT FRONT JUST OFFSHORE OF THE MID ATL COAST WILL SEE
MOISTURE BEGIN TO BE LIFTED OVER IT AND PULLED NWWD AS AN UPPER
LOW DEVELOPS SE OVER THE SOUTHERN APPALACHIANS. RAIN SHOULD
GRADUALLY EXPAND ACROSS THE SOUTHEAST PIEDMONT THURSDAY NIGHT AND
FRIDAY...THEN BEGIN TO DRIFT SLOWLY NWWD TWD CENTRAL PENN FRIDAY
INTO SATURDAY.
EVEN IF SOON TO BE HURRICANE JOAQUIN TAKES A TRACK OFFSHORE OF THE
MID ATL REGION PER THE EC AND LATEST TPC GUIDANCE...THE UPPER LOW
AND BACKING MID AND UPPER FLOW /WITH A HIGHLY ANOMALOUS -4 TO -5
SIGMA EASTERLY LLVL WIND AND AXIS OF HIGHER PWAT AIR/ WILL
TRANSPORT PULSE OF RAIN INLAND FROM THE ATLANTIC...UP AND OVER THE
VERY CHILLY AIRMASS ACROSS PENN. TEMPS SATURDAY...MAY STRUGGLE TO
CLIMB INTO THE LOWER 50S ACROSS THE CENTRAL AND NW MTNS...WHILE
THE SUSQ VALLEY COULD EDGE INTO THE UPPER 50S. THESE MAX TEMPS
WILL BE AT LEAST 10 DEG F BELOW NORMAL...AND POSSIBLY UP TO 15 DEG
IN SOME AREAS.
RIGHT NOW WE HAVE MDT AMOUNTS OF AROUND ONE INCH OF RAIN
FCST HEADING INTO THIS WEEKEND.
EXPECT THE NRN EDGE OF A 2 INCH/24 HOUR AREA OF RAIN SKIRTING OUR
SOUTHERN ZONES AND LOWER SUSQ VALLEY FOR LATE FRIDAY THROUGH
SATURDAY. THIS IS A PRE TYPE EVENT...WITH MORE DIRECT EFFECTS /IF
ANY/ FROM JOAQUIN COMING SUNDAY INTO MONDAY.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
STILL A FAIRLY WIDESPREAD SHIELD OF MVFR...WITH SOME IFR OVER THE
NW MOUNTAINS. CONDITIONS HAVE SLOWLY BEEN IMPROVING AND THIS
SHOULD CONTINUE INTO THE EVENING AS DRIER AIR FILTERS IN FROM THE
NORTH. THE HIGHEST CHANCE OF REMAINING SUB VFR WILL BE FROM
JOHNSTOWN NORTH INTO THE NORTHERN MOUNTAINS...BRADFORD
AREAS...BUT ELSEWHERE CEILINGS SHOULD IMPROVE TO 3000-5000` BY
NIGHTFALL.
NORTHERLY WINDS OF 10-15 KT GUSTING TO 20-25 KT WILL CONTINUE INTO
THE OVERNIGHT.
VFR CONDITIONS ARE EXPECTED OVER MOST OF THE AREA THURSDAY WITH
GUSTY WINDS CONTINUING.
OUTLOOK...
FRI-SUN...WIDESPREAD MVFR/IFR WITH RAIN DEVELOPING. GUSTY WINDS
POSSIBLE DEPENDING ON THE TRACK OF HURRICANE JOAQUIN.
SAT-MON...RAIN LIKELY WITH WIDESPREAD RESTRICTIONS DEVELOPING.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/MARTIN
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
201 PM EDT WED SEP 30 2015
.SYNOPSIS...
AN AREA OF LOW PRESSURE MOVING INTO NEW ENGLAND WILL BE FOLLOWED
BY WEAK HIGH PRESSURE. ANOTHER SIGNIFICANT RAIN EVENT IS POSSIBLE
FRIDAY INTO THE UPCOMING WEEKEND AS A DEEPENING UPPER LOW OVER THE
SOUTHERN APPALACHIANS DRAWS MOISTURE INLAND FROM THE WESTERN
ATLANTIC.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE SURFACE LOW AS OF 1PM IS AROUND PORTSMOUTH NH WITH A
FRESHENING NORTHERLY FLOW SETTING UP OVER MUCH OF THE LOCAL AREA
IN ITS WAKE. RADAR SHOWS LIGHT RETURNS IN THE REMAINS OF THE
DEFORMATION ZONE THAT EXTENDS FROM ABOUT TN UP INTO NRN NEW
ENGLAND.
THE FRESHENING NORTHERLY FLOW WILL BRING A PERIOD OF DRYER CONDITIONS
TO THE REGION WITH THE HRRR SUPPORTING THE IDEA OF JUST SOME
SCATTERED LIGHT SHOWERS GRADUALLY DIMINISHING BY NIGHTFALL.
THE TIGHTENING SFC PRESSURE GRADIENT WILL SUPPORT WINDS OF 10-15
MPH WITH GUSTS INTO THE LOW/MID 20S THIS AFTERNOON AND EVENING.
CLOUDS WILL HANG TOUGH OVERNIGHT AS THE BAROCLINIC ZONE ASSOCIATED
WITH THE COLD FRONT DOESN`T STRAY TOO FAR OFF TO OUR SOUTH AND
EAST. I DID HAVE A SMALL CHANCE OF A SHOWER OVER THE FAR SERN
ZONES...BUT FOR THE UPDATE I CHOSE TO KEEP IT DRY...BUT SHOWERS
WILL NOT BE TOO FAR AWAY OVER MD AND NJ.
OVERNIGHT LOWS WILL RANGE FROM AROUND 40 OVER THE NORTHERN
MOUNTAINS TO THE MID 50S OVER THE SOUTHEAST.
&&
.SHORT TERM /THURSDAY/...
THURSDAY WILL REMAIN CLOUDY OVER MOST OF THE AREA...WITH THE BEST
CHANCE OF SOME SUNSHINE BEING OVER THE NW ZONES FOR THE AFTERNOON
HOURS. OVER SERN PA...GUIDANCE DIFFERS AS TO HOW FAST AND HOW FAR
NORTH TO BRING SOME LIGHT RAIN DURING THE AFTERNOON. I LEANED
CLOSER TO A BLENDED MOS SOLUTION WHICH HAS A CHANCE OF RAIN FOR
ABOUT THE SERN 1/3 OF THE COUNTY WARNING AREA.
HIGHS THURSDAY LOOK LIKE THEY WILL AVERAGE A FEW DEGREES EITHER
SIDE OF 60...COOLER NORTH...MILDER SOUTH.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
STALLED OUT FRONT JUST OFFSHORE OF THE MID ATL COAST WILL SEE
MOISTURE BEGIN TO BE LIFTED OVER IT AND PULLED NWWD AS AN UPPER
LOW DEVELOPS SE OVER THE SOUTHERN APPALACHIANS. RAIN SHOULD
GRADUALLY EXPAND ACROSS THE SOUTHEAST PIEDMONT THURSDAY NIGHT AND
FRIDAY...THEN BEGIN TO DRIFT SLOWLY NWWD TWD CENTRAL PENN FRIDAY
INTO SATURDAY.
EVEN IF SOON TO BE HURRICANE JOAQUIN TAKES A TRACK OFFSHORE OF THE
MID ATL REGION PER THE EC AND LATEST TPC GUIDANCE...THE UPPER LOW
AND BACKING MID AND UPPER FLOW /WITH A HIGHLY ANOMALOUS -4 TO -5
SIGMA EASTERLY LLVL WIND AND AXIS OF HIGHER PWAT AIR/ WILL
TRANSPORT PULSE OF RAIN INLAND FROM THE ATLANTIC...UP AND OVER THE
VERY CHILLY AIRMASS ACROSS PENN. TEMPS SATURDAY...MAY STRUGGLE TO
CLIMB INTO THE LOWER 50S ACROSS THE CENTRAL AND NW MTNS...WHILE
THE SUSQ VALLEY COULD EDGE INTO THE UPPER 50S. THESE MAX TEMPS
WILL BE AT LEAST 10 DEG F BELOW NORMAL...AND POSSIBLY UP TO 15 DEG
IN SOME AREAS.
RIGHT NOW WE HAVE MDT AMOUNTS OF AROUND ONE INCH OF RAIN
FCST HEADING INTO THIS WEEKEND...AND THE LATEST GEFS SHOWS THE
NRN EDGE OF A 2 INCH/24 HOUR AREA OF RAIN SKIRTING OUR SOUTHERN
ZONES AND LOWER SUSQ VALLEY FOR LATE FRIDAY THROUGH SATURDAY. THIS
IS A PRE TYPE EVENT...WITH MORE DIRECT EFFECTS /IF ANY/ FROM
JOAQUIN COMING SUNDAY INTO MONDAY.
WILL CONTINUE WITH A MAINLY DRY FCST FOR MONDAY INTO TUE.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
STILL A FAIRLY WIDESPREAD SHIELD OF MVFR...WITH SOME IFR OVER THE
NW MOUNTAINS. CONDITIONS HAVE SLOWLY BEEN IMPROVING AND THIS
SHOULD CONTINUE INTO THE EVENING AS DRIER AIR FILTERS IN FROM THE
NORTH. THE HIGHEST CHANCE OF REMAINING SUB VFR WILL BE FROM
JOHNSTOWN NORTH INTO THE NORTHERN MOUNTAINS...BRADFORD
AREAS...BUT ELSEWHERE CEILINGS SHOULD IMPROVE TO 3000-5000` BY
NIGHTFALL.
NORTHERLY WINDS OF 10-15 KT GUSTING TO 20-25 KT WILL CONTINUE INTO
THE OVERNIGHT.
VFR CONDITIONS ARE EXPECTED OVER MOST OF THE AREA THURSDAY WITH
GUSTY WINDS CONTINUING.
OUTLOOK...
FRI-SUN...WIDESPREAD MVFR/IFR WITH RAIN DEVELOPING. GUSTY WINDS
POSSIBLE DEPENDING ON THE TRACK OF HURRICANE JOAQUIN.
SAT-MON...RAIN LIKELY WITH WIDESPREAD RESTRICTIONS DEVELOPING.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/MARTIN
AVIATION...LA CORTE
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
104 PM CDT WED SEP 30 2015
.UPDATE...FOR 18Z AVIATION DISCUSSION.
&&
.AVIATION UPDATE...18Z AVIATION DISCUSSION.
IMPACTS OF LIGHT SHWRS MOST POSSIBLE CSV THRU 30/20Z...BUT VFR CONDITIONS
EXPECTED AT MID STATE TAF SITES. CAN NOT TOTALLY RULE OUT LIGHT SHWRS
CKV/BNA...BUT VSBY IMPACTS ANTICIPATED TO BE MINIMAL...AND THUS WILL NOT
MENTION AT THIS TIME. PER EXPECTED DEEPENING OF UPPER LEVEL TROUGHING
ACROSS MID STATE...AND A CAA PATTERN SETTING UP BEHIND SFC FRONTAL PASSAGE...
POST FRONTAL MVFR TO IFR CLOUD COVERAGE EXPECTED. WITH SUSTAINED SFC WINDS
TO AROUND 10KTS EXPECTED ALSO...WITH OCCASIONALLY HIGHER GUSTS...FOG
POTENTIAL MAY BE LIMITED...AND ALTHOUGH IT MIGHT STILL DEVELOP...ESPECIALLY
01/06Z-01/14Z CKV/CSV...WILL NOT MENTION AS OF THIS TIME.
&&
.PREV DISCUSSION.../ISSUED 1231 PM CDT WED SEP 30 2015/
UPDATE...
HAVE UPDATED THE SUITE OF FORECAST PRODUCTS TO REMOVE ANY MORNING
WORDING FROM THE ZONE FORECAST PRODUCT...AND TO TWEAK HRLY TEMP...
DEWPOINT...SKY CONDITION...AND WIND SPEED/DIRECTION GRIDS.
PREV DISCUSSION.../ISSUED 1013 AM CDT WED SEP 30 2015/
UPDATE...
UPDATED THE SUITE OF FORECAST PRODUCTS TO REMOVE MENTION OF PATCHY
FOG EARLIER THIS MORNING. TWEAKED HRLY TEMP...DEWPOINT...SKY
CONDITION...AND WIND SPEED/DIRECTION GRIDS. PER LATEST HRRR MODEL
RUNS...AND IN LINE WITH CURRENT REGIONAL RADAR IMAGERY...TAILORED
BEST PCPN CHANCES OF RAINFALL THRU AFTERNOON HOURS ACROSS UPPER
CUMBERLAND REGION...WITH DECREASING RAINFALL CHANCES FOR OTHER
LOCATIONS ACROSS MID STATE.
PREV DISCUSSION.../ISSUED 636 AM CDT WED SEP 30 2015/
AVIATION UPDATE...FOR 12Z TAF`S.
BNA/CKV/CSV...UPPER TROUGH IS SITUATED OVER MIDDLE TENNESSEE THIS
MORNING WITH LOW CLOUDS AND A FEW SHOWERS ALREADY MOVING INTO THE
MID STATE. WITH THE DEEPER MOISTURE EAST OF MIDDLE TENNESSEE, FOG
AND LOW STRATUS WILL BE WORSE AT CSV, WITH CONDITIONS IMPROVING
FARTHER WEST. MAINLY SCATTERED SHOWERS ARE IN THE FORECAST TODAY,
AND GIVEN THE DIFFICULTY IN NAILING DOWN A SPECIFIC TIME AT EACH
TERMINAL, WILL HANDLE WITH VCSH REMARKS FOR NOW. WINDS WILL
INCREASE DURING THE DAY AS THE SURFACE PRESSURE GRADIENT TIGHTENS
UP. WINDS SHOULD STAY UP ENOUGH OVERNIGHT TO PREVENT DENSE FOG,
BUT CIGS WILL DROP BACK DOWN AFTER 00Z.
PREV DISCUSSION... /ISSUED 547 AM CDT WED SEP 30 2015/
UPDATE...BAND OF SCATTERED TO NUMEROUS SHOWERS HAS NOW EDGED INTO
NORTH-CENTRAL MIDDLE TN, JUST NORTH OF NASHVILLE, AND SHOULD
CONTINUE DROPPING EAST SOUTHEAST THROUGH MID-MORNING. AS A RESULT,
HAVE LOWERED RAIN TODAY`S POPS JUST A BIT OVER WESTERN COUNTIES,
AND REPLACED THE WORDING OF "SCATTERED" TO "CHANCE" TO REFLECT A
LOWERED CONFIDENCE FOR MEASURABLE RAIN TODAY. OTHERWISE, NO CHANGE
TO PREVIOUS FORECAST.
WILL RELEASE A NEW SUITE OF PRODUCTS TO REFLECT THESE "WESTERN
ADJUSTMENTS" SHORTLY.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 72 59 68 54 / 30 10 20 40
CLARKSVILLE 70 56 68 52 / 20 10 10 20
CROSSVILLE 72 57 62 52 / 60 30 50 60
COLUMBIA 74 59 70 52 / 30 10 20 30
LAWRENCEBURG 75 59 70 53 / 30 10 10 20
WAVERLY 71 58 70 52 / 20 10 10 20
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
1231 PM CDT WED SEP 30 2015
.UPDATE...
HAVE UPDATED THE SUITE OF FORECAST PRODUCTS TO REMOVE ANY MORNING
WORDING FROM THE ZONE FORECAST PRODUCT...AND TO TWEAK HRLY TEMP...
DEWPOINT...SKY CONDITION...AND WIND SPEED/DIRECTION GRIDS.
&&
.PREV DISCUSSION.../ISSUED 1013 AM CDT WED SEP 30 2015/
UPDATE...
UPDATED THE SUITE OF FORECAST PRODUCTS TO REMOVE MENTION OF PATCHY
FOG EARLIER THIS MORNING. TWEAKED HRLY TEMP...DEWPOINT...SKY
CONDITION...AND WIND SPEED/DIRECTION GRIDS. PER LATEST HRRR MODEL
RUNS...AND IN LINE WITH CURRENT REGIONAL RADAR IMAGERY...TAILORED
BEST PCPN CHANCES OF RAINFALL THRU AFTERNOON HOURS ACROSS UPPER
CUMBERLAND REGION...WITH DECREASING RAINFALL CHANCES FOR OTHER
LOCATIONS ACROSS MID STATE.
PREV DISCUSSION.../ISSUED 636 AM CDT WED SEP 30 2015/
AVIATION UPDATE...FOR 12Z TAF`S.
BNA/CKV/CSV...UPPER TROUGH IS SITUATED OVER MIDDLE TENNESSEE THIS
MORNING WITH LOW CLOUDS AND A FEW SHOWERS ALREADY MOVING INTO THE
MID STATE. WITH THE DEEPER MOISTURE EAST OF MIDDLE TENNESSEE, FOG
AND LOW STRATUS WILL BE WORSE AT CSV, WITH CONDITIONS IMPROVING
FARTHER WEST. MAINLY SCATTERED SHOWERS ARE IN THE FORECAST TODAY,
AND GIVEN THE DIFFICULTY IN NAILING DOWN A SPECIFIC TIME AT EACH
TERMINAL, WILL HANDLE WITH VCSH REMARKS FOR NOW. WINDS WILL
INCREASE DURING THE DAY AS THE SURFACE PRESSURE GRADIENT TIGHTENS
UP. WINDS SHOULD STAY UP ENOUGH OVERNIGHT TO PREVENT DENSE FOG,
BUT CIGS WILL DROP BACK DOWN AFTER 00Z.
PREV DISCUSSION... /ISSUED 547 AM CDT WED SEP 30 2015/
UPDATE...BAND OF SCATTERED TO NUMEROUS SHOWERS HAS NOW EDGED INTO
NORTH-CENTRAL MIDDLE TN, JUST NORTH OF NASHVILLE, AND SHOULD
CONTINUE DROPPING EAST SOUTHEAST THROUGH MID-MORNING. AS A RESULT,
HAVE LOWERED RAIN TODAY`S POPS JUST A BIT OVER WESTERN COUNTIES,
AND REPLACED THE WORDING OF "SCATTERED" TO "CHANCE" TO REFLECT A
LOWERED CONFIDENCE FOR MEASURABLE RAIN TODAY. OTHERWISE, NO CHANGE
TO PREVIOUS FORECAST.
WILL RELEASE A NEW SUITE OF PRODUCTS TO REFLECT THESE "WESTERN
ADJUSTMENTS" SHORTLY.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 72 59 68 54 / 30 10 20 40
CLARKSVILLE 70 56 68 52 / 20 10 10 20
CROSSVILLE 72 57 62 52 / 60 30 50 60
COLUMBIA 74 59 70 52 / 30 10 20 30
LAWRENCEBURG 75 59 70 53 / 30 10 10 20
WAVERLY 71 58 70 52 / 20 10 10 20
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31