Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 10/20/15
AREA FORECAST DISCUSSION
NWS TUCSON AZ
930 AM MST SUN OCT 18 2015
.SYNOPSIS...EXPECT LESS SHOWER AND THUNDERSTORM ACTIVITY INTO
MONDAY. A LOW PRESSURE SYSTEM WILL THEN BRING A GOOD CHANCE OF
SHOWERS AND THUNDERSTORMS TUESDAY INTO WEDNESDAY. A DRYING TREND
WILL START THURSDAY...THEN DRY CONDITIONS WILL OCCUR FRIDAY INTO
SATURDAY.
&&
.DISCUSSION...SATELLITE IMAGERY AND SURFACE OBSERVATIONS INDICATE
PARTLY CLOUDY TO MOSTLY CLOUDY SKIES ACROSS SE ARIZONA AT THIS TIME.
DEWPOINTS AT LOWER ELEVATIONS VALID 16Z WERE IN THE MID TO UPPER
50S...AND THESE TEMPS WERE GENERALLY UNCHANGED VERSUS 24 HOURS AGO.
SURFACE TEMPS VALID 16Z WERE NEARLY 3-8 DEGS F WARMER VERSUS THIS
TIME SAT. 18/12Z KTWC SOUNDING TOTAL PRECIP WATER VALUE WAS 1.02
INCHES...AND THIS VALUE WAS 0.12 INCH LOWER VERSUS 24 HOURS AGO. THE
ENVIRONMENT WAS MARGINALLY UNSTABLE WITH MUCAPE OF 584 J/KG AND
LIFTED INDEX OF MINUS 2. 18/12Z UPPER AIR PLOTS DEPICTED A TROUGH
OVER THE WRN CONUS WITH LOW PRESSURE CENTERED OVER NRN CALIFORNIA...
AND A NORTH-TO-SOUTH RIDGE OVER THE CENTRAL CONUS PLAINS. IR/WATER
VAPOR SATELLITE IMAGERY ALSO DEPICTED THE BACK EDGE OF MAINLY MID
AND HIGH-LEVEL CLOUDS REPRESENTING A SHORTWAVE TROUGH ALONG THE WEST
COAST OF NRN/CENTRAL BAJA CALIFORNIA. LIGHT TO MODERATE SWLY/WLY FLOW
ABOVE 700 MB PREVAILED ACROSS SE ARIZONA.
18/12Z NAM12...18/06Z UNIV OF ARIZONA WRF-NAM AND WRF-GFS AND
SEVERAL HRRR SOLUTIONS SUGGEST THAT THE FAVORED LOCALES FOR SHOWERS/
TSTMS INTO THIS EVENING WILL GENERALLY OCCUR NORTH-TO-NORTHEAST OF
TUCSON...OR ACROSS SE PINAL/GRAHAM/NRN GREENLEE COUNTIES. THE
INHERITED OFFICIAL FORECAST REFLECTS THIS NOTION...WITH CHANCE-
CATEGORY POPS ACROSS THIS AREA. THERE IS ENOUGH MOISTURE TO ALSO
SUPPORT AT LEAST ISOLATED COVERAGE OF SHOWERS/TSTMS FROM THE TOHONO
O`ODHAM NATION EWD INTO COCHISE COUNTY. PRECIP-FREE CONDITIONS
SHOULD OCCUR INTO THIS EVENING ACROSS WRN PIMA COUNTY. HOWEVER...
BASED ON SATELLITE TRENDS AS WELL AS THE 500-300 MB GFS MOISTURE
FIELDS...THE CIRRIFORM CLOUDS APPROACHING FROM THE SOUTHWEST MAY
BECOME FAIRLY THICK THIS AFTERNOON AND EVENING...ESPECIALLY WEST OF
TUCSON. HIGH TEMPS THIS AFTERNOON WILL AVERAGE A FEW DEGS ABOVE
NORMAL.
THERE ARE NO UPDATES PLANNED AT THIS TIME. PLEASE REFER TO THE
ADDITIONAL SECTIONS FOR FURTHER DETAIL.
&&
.AVIATION...VALID THRU 19/18Z.
SCATTERED -TSRA/-SHRA MAINLY FROM KTUS VICINITY NORTH-TO-NORTHEAST
ACROSS SE PINAL COUNTY TO THE WHITE MOUNTAINS NE OF KSAD THRU
TONIGHT. ISOLATED -SHRA/-TSRA MAY OCCUR MAINLY EAST OF KTUS MONDAY
MORNING. MVFR CONDITIONS WILL OCCUR WITH THE STRONGER THUNDERSTORMS.
OTHERWISE...SCATTERED TO BROKEN CLOUDS AROUND 8-12K FT AGL AND
BROKEN TO OVERCAST CLOUDS ABOVE 20K FT AGL WILL PREVAIL INTO MONDAY
MORNING. SURFACE WIND TODAY WILL GENERALLY BE SELY TO SWLY AT 5-15
KTS WITH GUSTS TO 20 KTS. SURFACE WIND WILL BE LESS THAN 10 KTS
THIS EVENING INTO MONDAY MORNING. AVIATION DISCUSSION NOT UPDATED
FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...SCATTERED SHOWERS AND THUNDERSTORMS WILL OCCUR TODAY
MAINLY NORTH TO NORTHEAST OF TUCSON FOLLOWED BY A SLIGHT CHANCE OF
SHOWERS AND THUNDERSTORMS MAINLY EAST OF TUCSON MONDAY. A LOW
PRESSURE SYSTEM WILL THEN BRING A GOOD CHANCE OF SHOWERS AND
THUNDERSTORMS TUESDAY AND WEDNESDAY. A DRYING TREND WILL START
THURSDAY...THEN DRY CONDITIONS FRIDAY INTO SATURDAY.
&&
.PREV DISCUSSION /312 AM MST/...MODELS SHOWED A BREAK IN THE RAINY
WEATHER MONDAY BEFORE ANOTHER SYSTEM EVOLVES OVER SOUTHERN CALIFORNIA
AND TRACKS EASTWARD THROUGH AZ ON TUESDAY INTO LATE WEDNESDAY. THIS
WILL BRING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS TO MUCH OF THE
AREA. UNTIL THEN...JUST EXPECTING SPOTTY SHOWERS AND A STRAY
THUNDERSTORM OR TWO. GFS AND ECMWF MODELS STILL SHOWED A VERY
PROGRESSIVE PATTERN IN PLACE THIS WEEK AS ANOTHER SYSTEM DEVELOPS
NEAR THE REGION AROUND THE WEEKEND. HIGH TEMPERATURES TODAY AND
MONDAY WILL REMAIN A FEW DEGREES ABOVE NORMAL...THEN BELOW NORMAL
DAYTIME READINGS WILL PREVAIL TUESDAY THROUGH THURSDAY. HIGHS WILL
TEND TO BE CLOSER TO SEASONAL NORMALS BY NEXT WEEKEND.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
830 AM MST SUN OCT 18 2015
.SYNOPSIS... A SERIES OF SLOW MOVING LOW PRESSURE SYSTEMS WILL BRING
ELEVATED CHANCES OF SHOWERS AND THUNDERSTORMS TO THE REGION THROUGH
THE MIDDLE OF THE WEEK. SHOWERS AND STORMS ARE POSSIBLE ACROSS SOUTH
CENTRAL AZ THIS AFTERNOON AS THE FIRST LOW PRESSURE SYSTEM PASSES
ACROSS THE REGION...WITH A MODEST DRYING TREND ON MONDAY. THIS WILL
BE SHORT LIVED AS A SECOND LOW MOVES INTO THE DESERT SOUTHWEST ON
TUESDAY...AND REMAINS IN PLACE THROUGH THURSDAY. DRIER AIR WILL THEN
MOVE INTO THE AREA LATE IN THE WEEK.
&&
.DISCUSSION... EARLY THIS MORNING...PLOTS AND VAPOR IMAGERY DEPICTED
A LARGE UPPER TROF ALONG THE WEST COAST...CENTERED OVER NRN
CALIFORNIA...WITH A PROMINENT SHORT WAVE ROTATING AROUND THE BASE OF
THE TROF AND MOVING ACROSS SRN CA AND APPROACHING ARIZONA. BROAD
UPPER DIFLUENCE WAS PRESENT OVER ARIZONA IN ADVANCE OF THE SHORT
WAVE...AND LOW LEVEL MOISTURE WAS ELEVATED WITH SURFACE DEWPOINTS
OVER THE DESERTS RANGING FROM THE MID 50S TO MID 60S. PROGS DEPICT
AN AREA OF MID LEVEL Q-CONVERGENCE MOVING INTO SERN CA AND ARIZONA
TODAY...AND CAPE WILL BE INCREASING AS WELL. SPC MESOANALYSIS
GRAPHICS FORECAST CAPE WELL IN EXCESS OF 1000 J/KG OVER MOST OF OUR
DESERTS BY EARLY AFTERNOON AND MODEL GUIDANCE ALSO INCREASES CAPE IN
A SIMILAR FASHION. AS SUCH WE EXPECT AN INCREASE IN SHOWERS AND
THUNDERSTORMS AS THE DAY PROGRESSES. WE HAVE RAISED POPS OVER MUCH
OF THE AREA WITH MANY LOCALES IN THE 20-30 PERCENT RANGE THIS
AFTERNOON...WITH HIGHER VALUES OVER THE HIGHER TERRAIN NORTH AND
EAST OF PHOENIX. AT 815 AM A NEW THUNDERSTORM DEVELOPED NEAR
FLORENCE JUNCTION...AN INDICATOR OF WHAT IS TO COME LATER IN THE
DAY. LATEST HRRR ALSO SUGGESTS SCATTERED SHOWERS/STORMS DEVELOPING
DURING THE DAY OVER THE DESERTS. CURRENT FORECASTS LOOK TO BE IN
GOOD SHAPE BUT WE WILL BE KEEPING AN EYE ON THE DEVELOPING WEATHER
IN CASE FURTHER UPDATES ARE NEEDED.
.PREVIOUS DISCUSSION...
EARLY MORNING WATER VAPOR IMAGERY REVEALS A SERIES OF
SHORTWAVE TROUGHS EMBEDDED WITHIN LARGER-SCALE TROUGHING ACROSS THE
WESTERN CONUS. A LARGE UPPER LOW REMAINED QUASI-STATIONARY OFF THE
NORTHERN CALIFORNIA COAST WHILE A WEAK SHORTWAVE/MCV THAT PRODUCED
STORMS SATURDAY EVENING WAS STILL POSITIONED OVER SOUTHEAST ARIZONA.
WEAK UPPER LEVEL SUPPORT IN THE FORM OF A 250MB JET STREAK OVER
NORTHERN BAJA CALIFORNIA HAS AIDED IN THE CONTINUED DEVELOPMENT AND
RE-GENERATION OF ISOLATED DESERT SHOWERS AND STORMS THIS MORNING
ALTHOUGH THE AREAL EXTENT OF THESE SHOWERS SINCE MIDNIGHT HAS
REMAINED LIMITED. THIS HAS...HOWEVER...ALLOWED CLOUD COVER TO REMAIN
IN PLACE AND CONSEQUENTLY HAS KEPT TEMPERATURES ON THE MILD SIDE
/GENERALLY IN THE MID 70S AS OF 09Z/.
THE FORECAST CONCERNS FOR TODAY WILL ONCE AGAIN BE DOMINATED BY AN
APPROACHING SHORTWAVE TROUGH FROM CALIFORNIA AND ITS IMPACTS AS IT
INTERACTS WITH A MODERATELY UNSTABLE ATMOSPHERE ACROSS PORTIONS OF
ARIZONA. THE WAVE ITSELF WILL DEEPEN LATER THIS MORNING AND MOVE
THROUGH ARIZONA THIS AFTERNOON. WITH MLCAPES ONCE AGAIN FORECAST TO
CLIMB INTO THE 250-500 J/KG RANGE...IT`S EASY TO ENVISION STORMS
DEVELOPING BY EARLY AFTERNOON AND RAPIDLY PUSHING EASTWARD INTO THE
MOUNTAINS. THE EXACT LOCATION WHERE STORMS WILL INITIATE IS UP FOR
DEBATE BUT A NUMBER OF HI-RES MODELS AND HI-RES ENSEMBLES DEPICT THE
BEST CHANCES FROM PHOENIX EASTWARD. AS SUCH...POPS HAVE BEEN REFINED
SLIGHTLY AND INCREASED INTO THE 30-40 PERCENT RANGE AROUND PHOENIX
AND INTO THE 50-60 PERCENT RANGE IN THE HIGHER TERRAIN LOCATIONS. ONE
CONCERN THAT COULD LIMIT STORM POTENTIAL IS THE ABUNDANT DRY AIR AND
ASSOCIATED MID LEVEL DRY ADVECTION THAT IS FORECAST LATER TODAY.
ALTHOUGH SIMILAR DRY ADVECTION DIDN`T HAVE TOO ADVERSE OF AN EFFECT
ON STORM CHANCES ON SATURDAY AND I`M HESITANT TO WRITE OFF TODAY`S
STORM CHANCES ENTIRELY.
THE UPPER LOW WILL MOVE SOUTHWARD SOMEWHAT ON MONDAY...RESULTING IN
SOME DEGREE OF SHORTWAVE RIDGING ACROSS THE AREA. WHILE STORM CHANCES
WON`T DIMINISH ENTIRELY...THEY SHOULD BE REDUCED QUITE A BIT FROM
WHAT WE`VE SEEN AS OF LATE AND BE RE-ORIENTED MAINLY TO THE
NORTH/EAST OF PHOENIX AND ALSO INTO NORTHERN ARIZONA. ALL IN ALL
MONDAY APPEARS TO BE FAIRLY QUIET AT THIS POINT BUT CLIMO-LIKE POPS
STILL SEEM WARRANTED GIVEN SLIGHTLY HIGHER THAN NORMAL PWATS AND
POSSIBLE SHORTWAVES NOT RESOLVED IN THIS MORNING`S MODEL GUIDANCE.
ALL SIGNS CONTINUE TO POINT TO THE UPPER LOW MIGRATING AND STALLING
OVER ARIZONA ON TUESDAY AND REMAINING IN PLACE THROUGH THURSDAY. NOT
MUCH HAS CHANGED IN THE DETERMINISTIC OR PROBABILISTIC GUIDANCE THIS
MORNING WITH NEARLY ALL MODELS INDICATING SLIGHTLY HIGHER THAN NORMAL
PWATS AND WATER VAPOR TRANSPORT...BUT WELL BELOW NORMAL HEIGHTS.
AFTERNOON INSTABILITY IS FORECAST TO RESIDE IN THE 250-500 J/KG RANGE
AND THE GFS/ECMWF BOTH SUGGEST A SHORTWAVE TROUGH WILL MOVE THROUGH
THE AREA TUESDAY AFTERNOON/EVENING. AS SUCH...POPS HAVE BEEN
INCREASED AND CLOSELY MIRROR THOSE PORTRAYED BY THE NAEFS. 40-50 POPS
ACROSS THE LOWER AZ DESERTS WITH EVEN HIGHER VALUES IN THE MOUNTAINS
EAST OF PHOENIX SEEM MORE THAN WARRANTED AT THIS POINT ALTHOUGH THERE
IS CONSIDERABLE UNCERTAINTY WITH RESPECT TO WHICH AREAS WILL SEE
LOCALLY HEAVY RAIN AND/OR STRONG STORMS. SOME OF THE CONSENSUS
GUIDANCE DEPICTS THE HIGHEST RAIN CHANCES ACROSS YUMA/LA PAZ AND GILA
COUNTIES WHILE LEADING MARICOPA/PINAL MAINLY DRY. NOT GOING TO SLICE
THINGS THAT THIN AT THIS POINT AND MAINTAIN NAEFS-LIKE VALUES TUESDAY
AND TUESDAY NIGHT.
WHILE THE LOW WILL REMAIN IN PLACE OVERHEAD WEDNESDAY AND
THURSDAY...MOISTURE WILL BEGIN TO SHIFT INTO NEW MEXICO AND FORECAST
SOUNDINGS GRADUALLY BECOME LESS AND LESS SUPPORTIVE OF STORMS ACROSS
THE AREA WEDNESDAY...AND EVEN MORE SO ON THURSDAY. MEANWHILE DRY
ADVECTION WILL BEGIN TO TAKE HOLD ACROSS SOUTHERN
CALIFORNIA...FURTHER REDUCING STORM CHANCES ACROSS THE AREA. POPS
WILL REMAIN ELEVATED IN LINE WITH CONS MODELS AND 00Z NAEFS DATA BUT
THERE SHOULD BE A CLEAR TREND TOWARD DRIER WEATHER LATE IN THE WEEK
INTO NEXT WEEKEND.
AS FOR TEMPERATURES OVER THE NEXT WEEK...SLIGHTLY ABOVE NORMAL HIGHS
ARE EXPECTED TODAY AND MONDAY. GIVEN THE ANOMALOUSLY LOW HEIGHTS
FORECAST TO RESIDE ACROSS THE AREA FROM TUESDAY THROUGH LATE
WEEK...IT SEEMS ALMOST CERTAIN THAT BELOW NORMAL TEMPS CAN BE
EXPECTED FROM MID WEEK ONWARD. EVEN WITH THE LOW DEPARTING LATE IN
THE WEEK/NEXT WEEKEND...PERSISTENT WEAK TROUGHING ALOFT SUGGESTS THAT
WE WON`T SEE ANY SIGNIFICANT WARMUPS AT ANY POINT IN THE NEXT WEEK.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
A FEW MORNING SHOWERS AND THUNDERSTORMS POSSIBLE ACROSS FAR EAST
VALLEY...INCLUDING KIWA...BUT AN EXPECTED BREAK THROUGH AROUND NOON.
EXPECTING ANOTHER ROUND OF SHOWERS AND POSSIBLY A FEW THUNDERSTORMS
THIS AFTERNOON...BUT NOT CONFIDENT ENOUGH TO GO ABOVE VICINITY FOR
AREA TERMINALS. EASTERLY SFC WINDS WILL BE FAVORED FOR MUCH OF THE
PERIOD...HOWEVER SHOULD HAVE A PERIOD OF SOUTHERLY TO WESTERLY FLOW
LATE THIS AFTERNOON AND EVENING. CIGS SHOULD REMAIN ABOVE 6K FT
THROUGH TONIGHT.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
LITTLE TO NO AVIATION CONCERN THROUGH MONDAY MORNING AS SHOWER
ACTIVITY LIKELY TO REMAIN NORTH AND EAST OF TERMINAL SITES. KBLH SFC
WINDS COULD BECOME GUSTY OUT OF THE SOUTH THIS AFTERNOON.
OTHERWISE...ONLY SCT CLOUD DECKS FOR THE PERIOD.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
UNSETTLED WEATHER DURING THE MIDDLE OF THE WEEK WILL TRANSITION TO
MUCH DRIER CONDITIONS LATE IN THE WEEK. WETTING RAINS WILL FAVOR
CENTRAL ARIZONA DISTRICTS...AND ESPECIALLY HIGHER TERRAIN LOCATIONS
NORTH AND EAST OF PHOENIX. AFTERNOON HUMIDITY VALUES IN A 25 TO 40
PERCENT RANGE EARLIER IN THE WEEK WILL DECREASE TO A 20 TO 30
PERCENT RANGE BY THE END OF NEXT WEEK. OVERNIGHT RECOVERY WILL BE
GOOD TO EXCELLENT. WIND SPEEDS WILL NOT BE PARTICULARLY
STRONG...WITH ONLY SOME OCCASIONAL HIGHER GUSTS IN SOUTHEAST
CALIFORNIA TUESDAY AND WEDNESDAY AFTERNOON.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT BASED ON STANDARD OPERATING
PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...CB
PREVIOUS DISCUSSION...LEINS
AVIATION...KUHLMAN
FIRE WEATHER...MO
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
810 PM PDT MON OCT 19 2015
.SYNOPSIS... PARTLY TO MOSTLY CLOUDY SKIES WITH A SLIGHT CHANCE FOR
SHOWERS THROUGH TUESDAY AS LOW PRESSURE DEVELOPS OVER THE REGION.
DAYTIME TEMPERATURES WILL BE NEAR NORMAL ON TUESDAY...THEN INCREASE
THROUGH THE END OF THE WEEK AS LOW PRESSURE SLOWLY MOVES EASTWARD
AND HIGH PRESSURE BUILDS.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
SATELLITE IMAGERY AND LOCAL OBSERVATIONS SHOWS A MIX OF HIGH...
MID...AND A FEW LOWER CLOUDS ACROSS SOCAL THIS EVENING. RADAR SHOWED
PERSISTENT SHOWERS OVER THE LA BASIN EARLY THIS EVENING...AND OTHER
BANDED STRUCTURES WITH WEAK SHOWERS FORMING OVER THE INLAND EMPIRE
AND OFFSHORE AT 8 PM PDT. THE 00Z MIRAMAR SOUNDING HAD A WEAK
INVERSION BASED NEAR 5200 FT AND LITTLE INSTABILITY. WINDS HAD
BACKED TO SOUTHERLY BELOW THE INVERSION AND THE COLUMN HAD DRIED
CONSIDERABLY WITH 0.81 INCH OF PW MEASURED. SURFACE PRESSURE
GRADIENTS SHOWED WEAK OFFSHORE TRENDS... BUT WERE STILL ABOUT 4 MBS
ONSHORE TO THE LOWER DESERTS AT 8 PM PDT.
A DYNAMIC TROUGH CONTINUES TO DIG OVER THE STATE. THE LATEST NAM12
HAS A NEW 566 DM LOW FORMING BY 12Z TUE ABOUT 100 MILES SW OF SAN
DIEGO. THIS KEEPS MOST OF THE LIFT WELL OFFSHORE...BUT CRATERS
HEIGHTS/THICKNESS OVER THE NEXT 12 HOURS. IT IS HARD TO RULE OUT AT
LEAST A SLIGHT CHANCE OF SHOWERS UNTIL THIS FEATURE SWINGS WELL
SOUTH OF THE REGION TUE EVENING.
THE HIRES MODELS HAVE HAD MUCH DIFFICULTY RESOLVING THE FORCING
TODAY...AND SOME OF THE SHOWERS HAVE BEEN HEAVY. THE LATEST HRRR RUN
SEEMS TO BE CATCHING ON WITH THE PATTERN THOUGH...AND KEEPS THE MAIN
LOW-LEVEL CONVERGENT LINE AND ASSOCIATED HEAVIER SHOWERS OVER OUR
COASTAL WATERS. IN GENERAL...SHOWERS ARE EXPECTED TO BE ISOLATED AND
LIGHT...BUT DUE TO THE WEAK FLOW AND TENDENCY TO TRAIN OVER THE SAME
AREAS...IF AND WHERE THEY DEVELOP...SPOTTY RAINFALL COULD BE
SUBSTANTIAL.
SUCCESSIVE RUNS OF THE MODELS ARE DOWNPLAYING THE OFFSHORE FLOW FOR
TUE/WED...SO FOR NOW IT LOOKS WEAK TO LOCALLY MODERATE AND CONFINED
TO THE WINDIER COASTAL SLOPES OF THE NORTHERN MOUNTAINS. THE WRAP-
AROUND NORTHERLY FLOW MAY CONTINUE SOME MID-LEVEL CLOUDS INTO WED AS
WELL. SO LOOK FOR ANOTHER RELATIVELY COOL DAY ON TUE...WITH SOME
WARMING ON WED.
AS SKIES CLEAR AND THE LOW GRADUALLY MOVES AWAY TO THE SE...
CONTINUED WARMING IS EXPECTED AS WEAK RIDGING TAKES A FOOTHOLD
ACROSS THE SW. FAIR AND WARMER THAN NORMAL WEATHER LOOKS LIKELY FOR
EARLY NEXT WEEK.
&&
.AVIATION...
200300Z...COAST AND VALLEYS...A MIX OF FEW-BKN LOW CLOUDS BETWEEN
2000 AND 5000 FT MSL WILL CONTINUE OVER THE REGION THROUGH 18Z
TUESDAY. CONFIDENCE IN CIGS BELOW 3000 FT MSL OCCURRING AT THE TAF
SITES THROUGH 18Z IS LOW TO MODERATE...AND HAVE LEFT SCT IN THE
KSAN...KCRQ...KSNA...AND KONT TAFS TO ACCOUNT FOR THIS. AFTER 18Z
TUESDAY...EXPECT FEW-SCT AOA 2500 FT MSL TO PREVAIL WITH LIGHT
WESTERLY WINDS.
MOUNTAINS/DESERTS...FEW-SCT BETWEEN 3000 AND 5000 FT MSL ALONG THE
WESTERN SLOPES OF THE MOUNTAINS THROUGH 18Z TUESDAY. OTHERWISE FEW-
BKN HIGH CLOUDS AOA 10000 FT MSL AND UNRESTRICTED VIS WILL PREVAIL
THROUGH TUESDAY.
&&
.MARINE...
800 PM...NO HAZARDOUS MARINE WEATHER IS EXPECTED THROUGH SATURDAY.
&&
.SKYWARN...
SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE
ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.
&&
$$
PUBLIC...JAD
AVIATION/MARINE...BA
AREA FORECAST DISCUSSION
NWS ALBANY NY
745 PM EDT MON OCT 19 2015
.SYNOPSIS...
HIGH PRESSURE WILL BUILD SOUTH AND EAST OF OUR REGION AND
OFFSHORE INTO TUESDAY. A COLD FRONT WILL TRACK SOUTH OUT OF
CANADA TONIGHT AND EARLY TUESDAY...AND BECOME STATIONARY JUST
SOUTH OF OUR AREA. WEAK HIGH PRESSURE WILL BUILD SOUTH OUT OF
CANADA TUESDAY NIGHT AND WEDNESDAY...BEFORE THE FRONT RETURNS
NORTH AS A WARM FRONT WEDNESDAY INTO WEDNESDAY NIGHT. A STRONG
COLD FRONT IS EXPECTED TO TRACK THROUGH THE AREA THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 730 PM EDT...SHOWERS HAVE PROGRESSED INTO THE ADIRONDACKS
AND PER THE LATEST OBS...WET BULB PROFILES APPEAR TO NOW REMAIN
ABOVE FREEZING. AS PER THE PREVIOUS UPDATE...WE HAVE EXPANDED THE
CLOUD COVERAGE BUT KEPT THE POP/WX IN THE SAME PLACES /ALONG AND
NORTH OF I90/. RATHER WEAK AND DIFFUSE ISENTROPIC LIFT SHOULD
KEEP ACTIVITY AS SCATTERED TONIGHT. THIS TOO IS SUPPORTED BY THE
LATEST HRRR WHICH POINTS TOWARD A HIGHER PROBABILITIES BY SUNRISE
WHICH SHOULD COINCIDE WITH THE UPSTREAM SHORT WAVE CURRENTLY
MOVING ACROSS THE CENTRAL GREAT LAKES REGION.
PREV DISC...
WARM ADVECTION IS BEGINNING AND UPPER ENERGY ALONG WITH A COLD
FRONT ARE TRACKING OUT OF CANADA INTO THE GREAT LAKES.
STRENGTHENING BOUNDARY LAYER WINDS...FRONTOGENESIS AND ISENTROPIC
LIFT WILL SUPPORT THE DEVELOPMENT OF SHOWERS ALONG THE COLD FRONT
LATER TONIGHT IN THE SOUTHERN ADIRONDACKS...WESTERN MOHAWK VALLEY
AND LAKE GEORGE AREA. THERE SHOULD BE LIMITED MOISTURE...BUT
STILL ENOUGH FOR SCATTERED...ALMOST LIKELY COVERAGE IN NORTHERN
AREAS.
DOWNSLOPE WIND FLOW AND SOME QUESTION AS TO JUST HOW FAR
SOUTH THE COLD FRONT WILL GET...SUGGESTS LESS CLOUD COVER FOR
AREAS FROM THE CAPITAL DISTRICT AND SOUTHERN VT AND POINTS SOUTH.
STILL SOME INTERVALS OF CLOUDS...PERHAPS TRENDING TO MOSTLY CLOUDY
IN THESE AREAS BY SUNRISE. COVERAGE OF SHOWERS ALSO RAPIDLY
DECREASES FROM NORTH TO SOUTH. SO...WITH SOME CLOUDS... SOME
MIXING DUE TO THE INCREASING BOUNDARY LAYER WINDS...AND SHOWERS TO
THE NORTH...LOWS IN THE MID 30S TO AROUND 40 IN MOST AREAS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
THERE IS SOME CONSENSUS IN SOURCES OF GUIDANCE THAT THE SURFACE
WIND SHIFT BOUNDARY TRACKS SOUTH OF THE REGION...BUT THE BOUNDARY
LAYER THERMAL GRADIENT DOES NOT QUITE MAKE IT SOUTH OF OUR
NORTHERN AREAS. SO...WITH WEAKENING WESTERLY BOUNDARY LAYER
FLOW...SOUTHWEST SURFACE WIND FLOW...AND LOOSENING OF THE
BOUNDARY LAYER THERMAL GRADIENT...SOME DOWNSLOPING PROCESSES AND
SOME INTERVALS OF CLOUDS AND SUN IS EXPECTED. ANY SCATTERED TO
ISOLATED SHOWERS LINGERING IN TUESDAY MORNING SHOULD END BY
AFTERNOON. HIGHS TUESDAY IN THE 60S...SOME UPPER 50S SOUTHERN
ADIRONDACKS.
ON TUESDAY NIGHT...THERE COULD BE A CONSIDERABLE CONTRAST IN LOW
TEMPERATURES FROM NORTH TO SOUTH...DEPENDING ON HOW MUCH HIGH
PRESSURE CAN BUILD SOUTH OUT OF CANADA. THERE IS QUITE A BIT OF
UNCERTAINTY AS TO HOW FAR SOUTH THE COLDER AIR TO THE NORTH CAN
SLOWLY DRAIN SOUTH...IF AT ALL...AND HOW FAR SOUTH ANY DEEPER
CLOUD COVER WILL BE. AT LEAST BASED ON CURRENT GUIDANCE...LOWS
TUESDAY NIGHT IN THE MID TO UPPER 40S...BUT UPPER 30S SOUTHERN
ADIRONDACKS AND LAKE GEORGE REGION.
ON WEDNESDAY STRONGER NORTHERN STREAM UPPER ENERGY BEGINS TO
APPROACH OUT OF CANADA...AND INCREASING WARM ADVECTION BEGINS. THE
OLD SURFACE WIND SHIFT BOUNDARY IS EXPECTED TO DRIFT NORTH AND
SURFACE WINDS MAY BE EAST TO SOUTHEAST MUCH OF THE DAY OVER MUCH
OF OUR REGION UNTIL THE WIND SHIFT BOUNDARY IS ABLE TO TRACK
THROUGH OUR AREA...THE TIMING OF WHICH IS QUITE UNCERTAIN. WITH
INCREASING SOUTHWEST TO WEST BOUNDARY LAYER FLOW...THE SURFACE WIND
SHIFT FROM EAST AND SOUTHEAST TO THE SOUTH AND SOUTHWEST MAY TAKE
ALL DAY OR INTO THE EVENING IN MOST AREAS...WHICH COULD RESULT IN
CONSIDERABLE CLOUDS AND SOME ISOLATED/SCATTERED SHOWERS...WHICH
WOULD LIMIT HIGH TEMPERATURES A BIT. BASED ON CURRENT GUIDANCE...
HIGHS WEDNESDAY IN THE LOW TO MID 60S...BUT AROUND 70 SOUTH AND
LOWER TO MID 50S NORTHERN AREAS.
GRADUAL INCREASE IN BOUNDARY LAYER WINDS...FRONTOGENESIS WITH
TIGHTENING THERMAL GRADIENT AND ISENTROPIC LIFT SUPPORTS
INCREASING COVERAGE OF CLOUDS AND SHOWERS WEDNESDAY NIGHT AND
THURSDAY. QUITE A BIT OF STRONG BOUNDARY LAYER THERMAL GRADIENT
FRONTOGENESIS SEEN IN SOURCES OF GUIDANCE FOR THURSDAY...WITH
SOME POSSIBLE WEAK SURFACE BASED INSTABILITY...BUT EVEN BETTER
MIDLEVEL LAPSE RATES. SOLID CHANCES FOR SHOWERS THURSDAY AND WILL
HAVE TO KEEP AN EYE FOR RUN TO RUN CONSISTENCY IN GUIDANCE FOR THE
POTENTIAL FOR THUNDERSTORMS. HIGHS THURSDAY IN THE MID 60S TO
AROUND 70...MID 50S TO AROUND 60 NORTHERN AREAS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE LONG TERM PERIOD WILL BE CHARACTERIZED BY MAINLY DRY AND
SEASONABLE WEATHER OUTSIDE A PERIOD OF SCATTERED SHOWERS ASSOCIATED
WITH A COLD FRONTAL PASSAGE SATURDAY NIGHT AND INTO THE DAY SUNDAY.
AT THE START OF THE LONG TERM PERIOD...THE LOW PRESSURE SYSTEM AND
UPPER-LEVEL TROUGH THAT WILL BE IMPACTING THE REGION AT THE END OF
THE SHORT TERM PERIOD WILL BE EXITING OFF TO THE NORTHEAST...WITH
IMPROVING CONDITIONS ACROSS MOST OF THE REGION. HAVE MAINTAINED
SLIGHT CHANCE AND CHANCE POPS MAINLY ACROSS THE SOUTHERN ADIRONDACKS
AND HIGHER TERRAIN OF SOUTHERN VERMONT AS LINGERING CYCLONIC FLOW
AROUND THE DEPARTING UPPER-LEVEL TROUGH AND A BRIEF PERIOD OF LAKE
ONTARIO ENHANCEMENT MAY PROMOTE SOME SCATTERED RAIN/SNOW SHOWERS
ACROSS THESE AREAS. ANY SNOW ACCUMULATIONS LOOK TO RANGE FROM A
COATING TO PERHAPS UP TO HALF AN INCH.
SURFACE HIGH PRESSURE AND RISING UPPER-LEVEL HEIGHTS WILL QUICKLY
BUILD ACROSS THE REGION FOR THE DAY FRIDAY WITH DRY WEATHER AND
PARTLY CLOUDY/MOSTLY SUNNY SKIES. IT WILL BE NOTICEABLY BREEZY
ACROSS THE REGION...ESPECIALLY DURING THE AFTERNOON HOURS AS A TIGHT
PRESSURE GRADIENT WILL REMAIN IN PLACE ACROSS THE REGION.
WINDS LOOK TO SUBSIDE WITH THE LOSS OF DAYTIME HEATING FRIDAY NIGHT
WITH HIGH PRESSURE REMAINING IN CONTROL CONTINUING THROUGH THE DAY
SATURDAY WITH PARTLY CLOUDY SKIES. A COLD FRONT THEN LOOKS TO MOVE
ACROSS THE REGION SOMETIME DURING THE SATURDAY NIGHT/SUNDAY
TIMEFRAME...AND HAVE TAKEN A BLEND OF THE LONG RANGE GUIDANCE DUE TO
TIMING DIFFERENCES SO FAR OUT AND GONE WITH CHANCE POPS FOR
SCATTERED SHOWERS. HIGH PRESSURE LOOKS TO BUILD ACROSS THE REGION
BEHIND THE COLD FRONT FOR THE START OF NEXT WEEK.
TEMPERATURES THROUGHOUT THE LONG TERM PERIOD WILL BE NEAR SEASONABLE
LEVELS FOR MID/LATE OCTOBER. HIGHS FRIDAY LOOK TO RANGE FROM THE
UPPER 30S/LOW 40S ACROSS THE SOUTHERN ADIRONDACKS TO UPPER 40S/LOW
50S ACROSS THE REST OF THE REGION. HIGHS SATURDAY LOOK TO RANGE FROM
THE UPPER 40S TO UPPER 50S AND A LITTLE WARMER ON SUNDAY RANGING
FROM LOW 50S TO NEAR 60...PERHAPS CRACKING 60 ACROSS THE MID HUDSON
VALLEY. HIGHS WILL BE A LITTLE COOLER ON MONDAY RANGING FROM THE MID
40S TO MID 50S.
LOWS THURSDAY NIGHT LOOK TO RANGE FROM THE UPPER 20S/LOW 30S ACROSS
THE SOUTHERN ADIRONDACKS TO UPPER 30S/LOW 40S ACROSS THE REST OF THE
REGION. LOWS FRIDAY NIGHT LOOK TO RANGE FROM THE UPPER 20S TO MID
30S ACROSS THE REGION WITH GOOD RADIATIONAL COOLING FROM THE HIGH
PRESSURE ACROSS THE REGION. LOWS SATURDAY AND SUNDAY NIGHT LOOK TO
RANGE FROM THE MID 30S TO LOW 40S.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
VFR CONDITIONS SHOULD PREVAIL THROUGH THE TAF FORECAST CYCLE
ENDING 00Z/WED. WHILE CLOUDS HAVE THICKENED AND LOWERED THIS
EVENING...CIGS REMAIN ABOVE CRITIAL THRESHOLDS. IN
ADDITION...REGIONAL RADAR REVEALS SHOWERS HAVE MADE IT INTO THE
ADIRONDACK PARK. PER THE LATEST HRRR...WE WILL BRING IN A `VCSH`
FOR ALL BUT KPOU AS FRONTAL BOUNDARY EVER SO SLIGHTLY DROPS
SOUTHWARD INTO THE REGION.
LOW LEVEL WIND SHEAR COULD BECOME AN ISSUE THROUGH ABOUT 14Z AS
THE LOW LEVEL JET MOVES INTO THE REGION...2000 FEET AGL WINDS
INCREASE TO AROUND 35 KNOTS. VAD WIND PROFILES UPSTREAM HAVE SHOWN
AN INCREASE TO >30KTS AND FORECAST PROFILES CONTINUE TO SUPPORT A
LOWERING OF THESE HIGHER MOMENTUM WINDS TO WARRANT AN INCLUSION
IN THE TAFS.
OUTLOOK...
TUESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
WEDNESDAY: LOW OPERATIONAL IMPACT. ISOLATED SHRA.
WEDNESDAY NIGHT: MODERATE OPERATIONAL IMPACT. ISOLATED SHRA.
THURSDAY: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA.
THURSDAY NIGHT THROUGH SATURDAY: NO OPERATIONAL IMPACT. NO SIG
WX.
&&
.FIRE WEATHER...
HIGH PRESSURE WILL BUILD SOUTH AND EAST OF OUR REGION AND
OFFSHORE INTO TUESDAY. A COLD FRONT WILL TRACK SOUTH OUT OF
CANADA TONIGHT AND EARLY TUESDAY...AND BECOME STATIONARY JUST
SOUTH OF OUR AREA. WEAK HIGH PRESSURE WILL BUILD SOUTH OUT OF
CANADA TUESDAY NIGHT AND WEDNESDAY...BEFORE THE FRONT RETURNS
NORTH AS A WARM FRONT WEDNESDAY INTO WEDNESDAY NIGHT. A STRONG
COLD FRONT IS EXPECTED TO TRACK THROUGH THE AREA THURSDAY.
RELATIVE HUMIDITY VALUES ARE EXPECTED TO RANGE BETWEEN 75 AND 10
PERCENT TONIGHT...THEN WILL DROP TO 35 TO 45 PERCENT IN SOUTHERN
AREAS AND 45 TO 60 PERCENT IN NORTHERN AREAS TUESDAY. RELATIVE
HUMIDITY VALUES ARE EXPECTED TO RANGE BETWEEN 75 AND 10 PERCENT
TUESDAY TONIGHT...THEN WILL DROP TO 45 TO 65 PERCENT WEDNESDAY
AFTERNOON.
WINDS WILL BE SOUTH TO SOUTHWEST AT 15 MPH OR LESS THROUGH
TUESDAY...WITH SOME POSSIBLE GUSTS AROUND 20 MPH TUESDAY
AFTERNOON...THEN SHIFT TO NORTH AND EAST AT LESS THAN 15 MPH
TUESDAY NIGHT AND WEDNESDAY.
&&
.HYDROLOGY...
NO HYDRO PROBLEMS ARE EXPECTED THROUGH THE NEXT 5 DAYS.
THERE IS A CHANCE OF LIGHT SHOWERS TONIGHT INTO TUESDAY
ESPECIALLY FOR AREAS NORTH OF THE CAPITAL REGION. MORE LIGHT
PRECIPITATION IS EXPECTED DURING THE MID WEEK PERIOD.
RIVER AND STREAM LEVELS WILL FALL A LITTLE OVER THE NEXT FEW DAYS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...NAS
NEAR TERM...BGM/NAS
SHORT TERM...NAS
LONG TERM...IRL
AVIATION...IAA/BGM
FIRE WEATHER...NAS
HYDROLOGY...NAS
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1036 AM EDT SUN OCT 18 2015
.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST ACROSS THE AREA THROUGH MONDAY THEN
SOUTH ACROSS THE MID ATLANTIC ON TUESDAY. A COLD FRONT APPROACHING
FROM THE NORTH ON TUESDAY WILL PASS THROUGH TUESDAY NIGHT. THIS
FRONT WILL MOVE BACK NORTH AS A WARM FRONT WEDNESDAY AS LOW
PRESSURE TRACKS THROUGH SOUTHERN CANADA AND NORTHERN NEW
ENGLAND...DRAGGING A COLD FRONT ACROSS ON THURSDAY. HIGH PRESSURE
RETURNS FOR FRIDAY AND SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TEMPERATURES RISING A LITTLE FASTER THAN FORECAST UNDER MOSTLY
CLEAR CONDITIONS AND NORTHWEST WIND 5 TO 10 KT. ALSO DEW POINTS A
FEW DEGREES HIGHER THIS MORNING...HOWEVER WITH MIXING DEW POINTS
WILL DROP OFF AGAIN THIS AFTERNOON.
INSTABILITY BKN STRATOCUMULUS CLOUDS ARE FORECAST TO REDEVELOP
MAINLY FROM 16Z/NOON UNTIL 20Z/4 PM WITH THE APPROACH OF THE COLD
UPPER LVL TROUGH AXIS. NAM AND HRRR CONTINUE TO INDICATE THE
POSSIBILITY OF SPRINKLES LATE THIS MORNING INTO THIS AFTERNOON IN
THE STRONG NORTHWEST FLOW...HOWEVER WITH LIMITED LOW LVL MOISTURE
IN PLACE...DECIDED NOT TO INCLUDE THEM IN THE FORECAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
FOR TONIGHT...WITH CANADIAN HIGH PRES ADVECTING EAST MUCH CLOSER
TO THE AREA...SFC WINDS WILL DECOUPLE EARLIER AS STRONGER RADIATIONAL
COOLING DEVELOPS ACROSS MORE OF THE LOCAL AREA THAN THIS MORNING.
FORECASTING WIDESPREAD TEMPS IN THE MID AND UPPER 20S...A KILLING
FREEZE...FOR THE SAME AREA UNDER A FREEZE WARNING THRU 10 AM THIS
MORNING. CLOSER TO THE COAST...FORECASTING TEMPS MAINLY IN THE
UPPER 20S AND LOW 30S RESULTING IN A MARGINAL FREEZE.
*NOTE THAT BASED ON AN ANALYSIS OF OVERNIGHT LOW TEMPS...WE MAY
DECIDE TO CANCEL THE FREEZE WARNING FOR PARTS OF THE REGION THAT
EXPERIENCED A KILLING FREEZE WITH OVERNIGHT LOWS IN THE 20S.
AS THE HIGH MOVES SOUTH OF THE AREA MONDAY...LOW LVL WARM AIR
ADVECTION DEVELOPS AS SW WINDS INCREASE DURG THE AFTN. TEMPS WILL
REMAIN ARND 10 DEGREES BELOW NORMAL.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
THROUGH THIS TIME FRAME...PROGRESSIVE WESTERLY FLOW EXPECTED AS
CLOSED UPPER LEVEL LOW WELL TO THE NORTH IN EASTERN CANADA MOVES
EAST MID WEEK...WITH SOUTHWESTERN UNITED STATES LOW REMAINING NEARLY
STATIONARY. NEXT SHORTWAVE IN CENTRAL CANADA DIVES SOUTHEASTWARD
ACROSS THE GREAT LAKES REGION MID WEEK...THEN PASSES ACROSS NORTHERN
NEW ENGLAND/SOUTHEAST CANADIAN PROVINCES THURSDAY. THERE ARE
DIFFERENCES IN THE STRENGTH OF THIS SHORTWAVE AS IT MOVES TO OUR
NORTH...BUT REASONABLE OVERALL AGREEMENT IS NOTED IN THE OPERATIONAL
MODEL SUITE.
RIDGE BUILDS BEHIND THIS DEPARTING TROUGH FRIDAY AND SATURDAY...OF
COURSE DEPENDENT ON EVENTUAL AMPLIFICATION OF THE TROUGH...WHICH AT
THIS STAGE IS UNCLEAR.
AT THE SFC...A COLD FRONT APPROACHES FROM THE NORTH MONDAY NIGHT AND
TUESDAY...EITHER PASSING JUST SOUTH OR REMAINING OVER THE AREA
TUESDAY NIGHT. THEN...THE FRONT WILL JUMP BACK TO THE NORTH AS A
WARM FRONT WEDNESDAY...AS THE UPPER TROUGH AND ASSOCIATED SFC COLD
FRONT APPROACHES. COLD FRONTAL PASSAGE SOMETIME LATER THURSDAY LOOKS
LIKELY. HIGH PRESSURE THEN BUILDS OUT OF CANADA FRIDAY AND SATURDAY.
AS FOR SENSIBLE WEATHER...A FEW SPRINKLES FROM TIME TO TIME CANNOT
BE RULED OUT TUE NIGHT THROUGH WED WITH THE FRONT IN OUR VICINITY.
HOWEVER...THE BEST CHANCE FOR SHOWERS LOOKS TO BE THURSDAY AHEAD OF
THE TROUGH WHEN BEST LIFT IS REALIZED. WILL MAINTAIN POPS IN THE
SLIGHT CHANCE RANGE DUE TO LACK OF DEEP MOISTURE. DO NOT FORESEE ANY
THUNDER PER STABILITY INDICES.
WITH WAA WELL UNDERWAY...EXPECT TEMPS TO REBOUND THROUGH MID WEEK.
NEAR TO SLIGHTLY ABOVE NORMAL READINGS ARE EXPECTED. A SLIGHT COOL
DOWN IS FORECAST BEHIND THE FRONT LATE WEEK...WITH TEMPS AVERAGING
SLIGHTLY BELOW NORMAL BY THEN.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE BUILDS TODAY AND TONIGHT.
VFR. SCT-BKN STRATOCU FOR THE AFTN BEFORE CLOUDS GIVE WAY TO
CLEARING THIS EVENING. AN ISOLATED SHOWER OR SPRINKLE CANNOT BE
RULED OUT THIS AFTERNOON.
NW WIND 10 TO 15 KTS WILL PREVAIL TODAY. GUSTS UP TO 20 KTS ARE ALSO
ANTICIPATED...BUT POSSIBLY ONLY OCCASIONAL FOR SOME TERMINALS. WINDS
ABATE SHORTLY AFTER SUNSET.
FOR NYC METRO...WIND DIRECTION SHOULD GENERALLY REMAIN TO THE RIGHT
OF 310 MAGNETIC.
.OUTLOOK FOR 12Z MON THROUGH THU...
.MON-WED...VFR. SW WINDS G20-25KT ON TUESDAY.
.THU...MAINLY VFR BUT LOCAL MVFR POSSIBLE WITH A SLIGHT CHANCE OF
SHOWERS.
&&
.MARINE...
NO CHANGES AT THIS TIME.
NW WIND 15 TO 20 KT WITH OCCASIONAL GUSTS UP TO 25 KT WILL
CONTINUE THROUGH TODAY WITH SEAS OF 2-4 FT ACROSS NEARSHORE
ATLANTIC WATERS.
TONIGHT...BECAUSE FCST MODELS SHOW AN INCREASING NW PRES
GRADIENT...A SMALL CRAFT ADVISORY WAS ISSUED FOR THE ATLANTIC
COASTAL WATERS FROM 8 PM THIS EVENING UNTIL 6 AM MONDAY MORNING.
NW WINDS 20-25 KT WITH SEAS OF 3-4 FT ARE FORECAST.
MONDAY...WINDS WILL BECOME WSW BY AFTERNOON AT 15-20 KT WITH SEAS
OF 3-4 FT AS HIGH PRES MVS SOUTH OF THE AREA.
A TIGHTENING PRESSURE GRADIENT AHEAD OF AN APPROACHING COLD FRONT
FROM THE NORTH WILL ALLOW WEST/SW WINDS TO INCREASE MONDAY NIGHT AND
REMAIN RATHER STRONG TUESDAY. SCA CONDITIONS ARE LIKELY FOR MOST OF
THE AREA WATERS...WITH OCEAN SEAS BUILDING PER WAVE WATCH. AS THE
FRONT MOVES THROUGH OR SETTLES NEARBY TUESDAY NIGHT...WINDS WILL
DIMINISH AND SEAS WILL SUBSIDE. THE FRONT THEN MOVES BACK TO THE
NORTH AS A WARM FRONT LATER WEDNESDAY.
AS SUCH...WINDS WILL SHIFT FROM THE W TUE NIGHT TO THE N LATE TUE
NIGHT INTO WED...ALTHOUGH THAT DEPENDS ON HOW FAR SOUTH THE FRONT
SETTLES. THEN WINDS SHIFT BACK AROUND TO THE SOUTH WED NIGHT...AND
SW THURSDAY AHEAD OF THE APPROACHING COLD FRONT. ANOTHER WIND SHIFT
OCCURS THU NIGHT AS THE COLD FRONT MOVES THROUGH.
&&
.FIRE WEATHER...
A DRY AIR MASS COMBINED WITH NORTHWEST WINDS OF 10 TO 20 MPH...LOW
HUMIDITY OF 25 TO 35 PERCENT AND NO MEASURABLE RAIN DURING THE PAST
WEEK WILL CONTINUE TO CREATE CONDITIONS MORE CONDUCIVE FOR FIRE SPREAD
FROM LATE THIS MORNING UNTIL SUNSET TODAY.
&&
.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION IS EXPECTED THROUGH THE FORECAST PERIOD.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...FREEZE WARNING FROM 2 AM TO 10 AM EDT MONDAY FOR CTZ005>012.
NY...FREEZE WARNING FROM 2 AM TO 10 AM EDT MONDAY FOR NYZ067>071-
078>081-177.
NJ...FREEZE WARNING FROM 2 AM TO 10 AM EDT MONDAY FOR NJZ002-004-
103>105-107.
MARINE...SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 6 AM EDT MONDAY
FOR ANZ350-353-355.
&&
$$
SYNOPSIS...GC/PW
NEAR TERM...MET
SHORT TERM...GC
LONG TERM...PW
AVIATION...JC
MARINE...MET
FIRE WEATHER...
HYDROLOGY...GC/PW
AREA FORECAST DISCUSSION
NWS GOODLAND KS
433 PM MDT SUN OCT 18 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 117 PM MDT SUN OCT 18 2015
WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS RIDGE CENTERED OVER
SOUTHERN PLAINS AND CLOSED LOW CENTERED OVER NORTHERN CALIFORNIA. A
UPPER LEVEL SHORTWAVE TROUGH CURRENTLY EXTENDS FROM THE NEBRASKA
PANHANDLE AND ALONG CO/KS BORDER. AT THE SURFACE LEE TROUGH HAS
DEEPENED ACROSS EASTERN COLORADO WITH SW GRADIENT ACROSS OUR CWA. A
WARM FRONT HAS LIFTED NORTH OF KMCK AND TEMPS ACROSS THE REGION HAVE
WARMED INTO THE UPPER 70S/LOWER 80S EARLY THIS AFTERNOON.
TONIGHT-MONDAY...WEAK FORCING ASSOCIATED WITH SEVERAL PASSING UPPER
LEVEL SHORTWAVE TROUGHS WILL RESULT IN PASSING HIGH CLOUD COVER AND
LITTLE ELSE. GFS DOES SHOW A LITTLE BETTER MID LEVEL MOISTURE
ADVECTION AND A SMALL AREA OF LIGHT QPF ACROSS OUR NORTH. DRY
MOISTURE PROFILES BELOW THESE ELEVATED MOIST LAYER EVEN WITH GFS
WOULD LIKELY BE TOO MUCH TO OVERCOME AND PRECIP IS NOT EXPECTED. LEE
TROUGH WILL SHIFT EASTWARD IN RESPONSE TO DEEPENING TROUGH IN THE
WEST AND SHIFT TO SW FLOW ALOFT. GRADIENT WILL WEAKEN AS A RESULT
AND WINDS SHOULD BE CONSIDERABLY LIGHTER COMPARED TO TODAY. A VERY
SIMILAR AIR MASS WILL BE IN PLACE AND ABOVE NORMAL HIGHS IN THE
LOWER 80S TO MID 80S ARE EXPECTED. THE MAIN COMPLICATION WILL BE
THICKNESS/COVERAGE OF MID TO HIGH CLOUD COVER. CLOUD COVER APPEARS
TO BE FAIRLY PROGRESSIVE WITHIN SW FLOW...SO AT THIS TIME
ANTICIPATED IMPACT ON HIGHS SHOULD BE MINIMAL.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 118 PM MDT SUN OCT 18 2015
SOUTHWESTERLY FLOW ALOFT AHEAD OF THE CUT OFF SYSTEM IN THE DESERT
SOUTHWEST WILL CONTINUE THROUGH WEDNESDAY BEFORE IT FINALLY LIFTS
OUT AND ACROSS THE CENTRAL PLAINS WEDNESDAY NIGHT AND THURSDAY.
RAIN CHANCES WILL GRADUALLY INCREASE AHEAD OF THE MAIN SYSTEM WITH
THE BEST CHANCES FOR RAIN OCCURRING WEDNESDAY NIGHT THROUGH THE
DAY ON THURSDAY. 48-HOUR QPF TOTALS ENDING AT 12Z FRIDAY ARE
ACTUALLY QUITE SIMILAR FROM THE GFS AND ECMWF...WITH 1 TO 2 INCHES
FORECAST SOUTH OF INTERSTATE 70 AND 0.50 TO 1 INCH GENERALLY NORTH
OF THE INTERSTATE. A FAVORABLE TROPICAL MOISTURE FETCH IN MID
LEVELS AND GOOD MOISTURE ADVECTION FROM THE SOUTHEAST IN THE LOWER
LEVELS RESULT IN PRECIPITABLE WATER VALUES APPROACHING 200 PERCENT
OF NORMAL LEADING UP TO THE ARRIVAL OF THE SYSTEM. RAIN WILL
GRADUALLY END WEST TO EAST ON FRIDAY. TEMPERATURES WILL BE ABOVE
NORMAL TUESDAY...NEAR NORMAL ON WEDNESDAY...BELOW NORMAL ON
THURSDAY THEN NEAR TO SLIGHTLY BELOW NORMAL FRIDAY THROUGH SUNDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 429 PM MDT SUN OCT 18 2015
VFR CONDITIONS WILL CONTINUE AT KGLD AND KMCK FOR THE NEXT 24
HOURS. BREEZY SOUTH WINDS WILL PERSIST TONIGHT WITH SOME LOW LEVEL
WIND SHEAR AT KMCK. WINDS DECREASE MONDAY AS THE SURFACE TROUGH
MOVES EAST NEAR KGLD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...024
AVIATION...FS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
137 PM MDT SUN OCT 18 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 117 PM MDT SUN OCT 18 2015
WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS RIDGE CENTERED OVER
SOUTHERN PLAINS AND CLOSED LOW CENTERED OVER NORTHERN CALIFORNIA. A
UPPER LEVEL SHORTWAVE TROUGH CURRENTLY EXTENDS FROM THE NEBRASKA
PANHANDLE AND ALONG CO/KS BORDER. AT THE SURFACE LEE TROUGH HAS
DEEPENED ACROSS EASTERN COLORADO WITH SW GRADIENT ACROSS OUR CWA. A
WARM FRONT HAS LIFTED NORTH OF KMCK AND TEMPS ACROSS THE REGION HAVE
WARMED INTO THE UPPER 70S/LOWER 80S EARLY THIS AFTERNOON.
TONIGHT-MONDAY...WEAK FORCING ASSOCIATED WITH SEVERAL PASSING UPPER
LEVEL SHORTWAVE TROUGHS WILL RESULT IN PASSING HIGH CLOUD COVER AND
LITTLE ELSE. GFS DOES SHOW A LITTLE BETTER MID LEVEL MOISTURE
ADVECTION AND A SMALL AREA OF LIGHT QPF ACROSS OUR NORTH. DRY
MOISTURE PROFILES BELOW THESE ELEVATED MOIST LAYER EVEN WITH GFS
WOULD LIKELY BE TOO MUCH TO OVERCOME AND PRECIP IS NOT EXPECTED. LEE
TROUGH WILL SHIFT EASTWARD IN RESPONSE TO DEEPENING TROUGH IN THE
WEST AND SHIFT TO SW FLOW ALOFT. GRADIENT WILL WEAKEN AS A RESULT
AND WINDS SHOULD BE CONSIDERABLY LIGHTER COMPARED TO TODAY. A VERY
SIMILAR AIR MASS WILL BE IN PLACE AND ABOVE NORMAL HIGHS IN THE
LOWER 80S TO MID 80S ARE EXPECTED. THE MAIN COMPLICATION WILL BE
THICKNESS/COVERAGE OF MID TO HIGH CLOUD COVER. CLOUD COVER APPEARS
TO BE FAIRLY PROGRESSIVE WITHIN SW FLOW...SO AT THIS TIME
ANTICIPATED IMPACT ON HIGHS SHOULD BE MINIMAL.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 118 PM MDT SUN OCT 18 2015
SOUTHWESTERLY FLOW ALOFT AHEAD OF THE CUT OFF SYSTEM IN THE DESERT
SOUTHWEST WILL CONTINUE THROUGH WEDNESDAY BEFORE IT FINALLY LIFTS
OUT AND ACROSS THE CENTRAL PLAINS WEDNESDAY NIGHT AND THURSDAY.
RAIN CHANCES WILL GRADUALLY INCREASE AHEAD OF THE MAIN SYSTEM WITH
THE BEST CHANCES FOR RAIN OCCURRING WEDNESDAY NIGHT THROUGH THE
DAY ON THURSDAY. 48-HOUR QPF TOTALS ENDING AT 12Z FRIDAY ARE
ACTUALLY QUITE SIMILAR FROM THE GFS AND ECMWF...WITH 1 TO 2 INCHES
FORECAST SOUTH OF INTERSTATE 70 AND 0.50 TO 1 INCH GENERALLY NORTH
OF THE INTERSTATE. A FAVORABLE TROPICAL MOISTURE FETCH IN MID
LEVELS AND GOOD MOISTURE ADVECTION FROM THE SOUTHEAST IN THE LOWER
LEVELS RESULT IN PRECIPITABLE WATER VALUES APPROACHING 200 PERCENT
OF NORMAL LEADING UP TO THE ARRIVAL OF THE SYSTEM. RAIN WILL
GRADUALLY END WEST TO EAST ON FRIDAY. TEMPERATURES WILL BE ABOVE
NORMAL TUESDAY...NEAR NORMAL ON WEDNESDAY...BELOW NORMAL ON
THURSDAY THEN NEAR TO SLIGHTLY BELOW NORMAL FRIDAY THROUGH SUNDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1121 AM MDT SUN OCT 18 2015
VFR CONDITIONS WILL CONTINUE AT BOTH KGLD AND KMCK THROUGH THE
TAF PERIOD. TIGHT SURFACE GRADIENT IS IN PLACE OVER KGLD EAST OF
DEEPENING SURFACE LOW OVER EASTERN COLORADO. AS WARM FRONT OVER
KMCK LIFTS NORTH SOUTHERLY GRADIENT WILL MOVE OVER KMCK TERMINAL
AS WELL (WITHIN THE NEXT HOUR). RESULT WILL BE GUSTY WINDS WITH
GUSTS AROUND 30KT...POSSIBLY AS HIGH AS 35 KT THIS AFTERNOON. PEAK
WIND GUSTS WILL END WITH LOSS OF DAYTIME HEATING AT
SUNSET...HOWEVER WITH LOW LEVEL JET LINGERING THROUGH THE NIGHT
OVER KMCK I WOULD EXPECT LOW LEVEL WIND SHEER TO DEVELOP. THIS
WOULD THEN LAST THROUGH AROUND 8Z WHEN THE LLJ FINALLY TRANSITIONS
EAST.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...024
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
117 PM MDT SUN OCT 18 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 117 PM MDT SUN OCT 18 2015
WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS RIDGE CENTERED OVER
SOUTHERN PLAINS AND CLOSED LOW CENTERED OVER NORTHERN CALIFORNIA. A
UPPER LEVEL SHORTWAVE TROUGH CURRENTLY EXTENDS FROM THE NEBRASKA
PANHANDLE AND ALONG CO/KS BORDER. AT THE SURFACE LEE TROUGH HAS
DEEPENED ACROSS EASTERN COLORADO WITH SW GRADIENT ACROSS OUR CWA. A
WARM FRONT HAS LIFTED NORTH OF KMCK AND TEMPS ACROSS THE REGION HAVE
WARMED INTO THE UPPER 70S/LOWER 80S EARLY THIS AFTERNOON.
TONIGHT-MONDAY...WEAK FORCING ASSOCIATED WITH SEVERAL PASSING UPPER
LEVEL SHORTWAVE TROUGHS WILL RESULT IN PASSING HIGH CLOUD COVER AND
LITTLE ELSE. GFS DOES SHOW A LITTLE BETTER MID LEVEL MOISTURE
ADVECTION AND A SMALL AREA OF LIGHT QPF ACROSS OUR NORTH. DRY
MOISTURE PROFILES BELOW THESE ELEVATED MOIST LAYER EVEN WITH GFS
WOULD LIKELY BE TOO MUCH TO OVERCOME AND PRECIP IS NOT EXPECTED. LEE
TROUGH WILL SHIFT EASTWARD IN RESPONSE TO DEEPENING TROUGH IN THE
WEST AND SHIFT TO SW FLOW ALOFT. GRADIENT WILL WEAKEN AS A RESULT
AND WINDS SHOULD BE CONSIDERABLY LIGHTER COMPARED TO TODAY. A VERY
SIMILAR AIR MASS WILL BE IN PLACE AND ABOVE NORMAL HIGHS IN THE
LOWER 80S TO MID 80S ARE EXPECTED. THE MAIN COMPLICATION WILL BE
THICKNESS/COVERAGE OF MID TO HIGH CLOUD COVER. CLOUD COVER APPEARS
TO BE FAIRLY PROGRESSIVE WITHIN SW FLOW...SO AT THIS TIME
ANTICIPATED IMPACT ON HIGHS SHOULD BE MINIMAL.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 142 AM MDT SUN OCT 18 2015
THE EXTENDED PERIOD BEGINS WITH THE APPROACH OF A CUT OFF AREA OF
LOW PRESSURE AND ASSOCIATED SLIGHTLY NEGATIVE TROUGH. THIS LOW WILL
MOVE NORTHEASTWARD THROUGH THE DAY ON WEDNESDAY AND INTO EARLY
THURSDAY. GUIDANCE IS IN GOOD AGREEMENT WITH REGARDS TO THE LOW
OPENING AND BECOMING A PART OF THE MAIN TROUGH HOWEVER TEMPORAL
AGREEMENT IS WEAK. POPS ON WEDNESDAY WILL BE IN THE 30 TO 50 PERCENT
RANGE NORTH TO SOUTH AS THE SOUTHERN PORTION OF THE CWA WILL HAVE
SLIGHTLY BETTER OMEGA VALUES THANKS TO FAVORABLE POSITIONING OF THE
JET. THIS AXIS WILL SHIFT NORTH AS WE HEAD INTO THURSDAY WITH MUCH
OF THE CWA NOW POTENTIALLY SEEING 40 TO 60 PERCENT POPS ESPECIALLY
DURING THE MIDDAY TO EARLY AFTERNOON HOURS. THE SYSTEM WILL SLOWLY
MOVE OFF TO THE NORTH AND EAST EARLY FRIDAY WITH SHOWERS AND
EMBEDDED THUNDERSTORMS TAPERING OFF FROM WEST TO EAST DURING THE
DAY. THE EASTERN PORTIONS OF THE CWA WILL SEE RAIN CHANCES PERSIST
INTO SATURDAY MORNING HOWEVER MOST ACTIVITY WILL WIND DOWN JUST
BEFORE SUNRISE. THERE IS A POSSIBILITY FOR LOW VISIBILITIES DUE TO
MIST OR FOG ON WEDNESDAY... THURSDAY AND FRIDAY MORNING DUE TO NEAR
ZERO DEW POINT DEPRESSIONS AND A FAVORABLE WIND STRUCTURE.
TEMPERATURES DURING THE FORECAST PERIOD WILL BE NEAR TO SLIGHTLY ABOVE
AVERAGE WITH HIGHS IN THE LOWER 60S AND LOWS IN THE LOW TO MID 40S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1121 AM MDT SUN OCT 18 2015
VFR CONDITIONS WILL CONTINUE AT BOTH KGLD AND KMCK THROUGH THE
TAF PERIOD. TIGHT SURFACE GRADIENT IS IN PLACE OVER KGLD EAST OF
DEEPENING SURFACE LOW OVER EASTERN COLORADO. AS WARM FRONT OVER
KMCK LIFTS NORTH SOUTHERLY GRADIENT WILL MOVE OVER KMCK TERMINAL
AS WELL (WITHIN THE NEXT HOUR). RESULT WILL BE GUSTY WINDS WITH
GUSTS AROUND 30KT...POSSIBLY AS HIGH AS 35 KT THIS AFTERNOON. PEAK
WIND GUSTS WILL END WITH LOSS OF DAYTIME HEATING AT
SUNSET...HOWEVER WITH LOW LEVEL JET LINGERING THROUGH THE NIGHT
OVER KMCK I WOULD EXPECT LOW LEVEL WIND SHEER TO DEVELOP. THIS
WOULD THEN LAST THROUGH AROUND 8Z WHEN THE LLJ FINALLY TRANSITIONS
EAST.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...TL
AVIATION...DR
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
902 AM CDT SUN OCT 18 2015
...UPDATE TO SYNOPSIS...
.SYNOPSIS...
ISSUED AT 900 AM CDT SUN OCT 18 2015
WV Imagery indicates a weak upper level ridge of high pressure
transitioning eastward across the Central Plains. Meanwhile, an
upper level trough of low pressure is pushing ashore off the Pacific
into the Pacific Northwest and northern California. Near the
surface, a lee side trough of low pressure is slowly strengthening
across extreme eastern Colorado.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 314 AM CDT SUN OCT 18 2015
Efficient mixing is expected as the boundary layer depth increases
this late this morning and afternoon. GFS LAMP indicates gusts into
the mid 30s knots range as winds turn southwest and result in
downslope and enhanced adiabatic warming for highs approaching 80
degrees. Despite the upper ridge beginning to break down across
the Central Plains on Monday, the 850 mb temperatures across the
high plains increases by Monday afternoon. Temperatures along and
ahead of the eastern Colorado trough should exceed 80 degrees
Monday afternoon. The axis of breezy to windy southwest wind
should gradually move farther east into central Kansas as well.
.LONG TERM...(Monday THROUGH Saturday)
ISSUED AT 314 AM CDT SUN OCT 18 2015
The continued warming trend should extend into Tuesday in advance of
the approaching upper low moving into the desert sw/southern Rockies
region. GFS MOS indicated low to mid 80s possible which at this
point is a good 15 degrees or more above normal highs. The system
has been modeled for several runs now as a closed low weakening to a
mid tropospheric open wave moving into the central and southern
Plains around Thursday. Highest pops starts about Thursday
morning and last through Thursday night/early Friday. With the
initial advance of cloudiness and possible showers and
thunderstorms Wednesday along the warm conveyor belt/mid level
baroclinic zone intersection, forecast high temperatures are cut
10 to 15 degrees in Wednesday. Highs may be relegated to the 60s
and 70s for the remainder of the week.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z Monday MORNING)
ISSUED AT 600 AM CDT SUN OCT 18 2015
Gusty south winds of 20 to near 25 knots will develop by the early
afternoon as 35 to 45 knots winds located in the 900mb to 850mb
level mixes down to the surface. These very windy conditions are
expected to fall back into the 15 to 20 knot range after sunset.
06z NAM BUFR Moisture profiles along with the latest RAP and HRRR
indicate VFR conditions today and tonight.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 79 55 82 59 / 0 0 0 0
GCK 80 55 83 58 / 0 0 0 0
EHA 78 55 83 56 / 0 0 0 0
LBL 80 55 83 58 / 0 0 0 0
HYS 80 57 82 60 / 0 0 0 0
P28 78 57 82 58 / 0 0 0 0
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SYNOPSIS...JJohnson
SHORT TERM...Russell
LONG TERM...Russell
AVIATION...Burgert
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
602 AM CDT SUN OCT 18 2015
...Updated Aviation Discussion...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 314 AM CDT SUN OCT 18 2015
Efficient mixing is expected as the boundary layer depth increases
this late this morning and afternoon. GFS LAMP indicates gusts into
the mid 30s knots range as winds turn southwest and result in
downslope and enhanced adiabatic warming for highs approaching 80
degrees. Despite the upper ridge beginning to break down across
the Central Plains on Monday, the 850 mb temperatures across the
high plains increases by Monday afternoon. Temperatures along and
ahead of the eastern Colorado trough should exceed 80 degrees
Monday afternoon. The axis of breezy to windy southwest wind
should gradually move farther east into central Kansas as well.
.LONG TERM...(Monday THROUGH Saturday)
ISSUED AT 314 AM CDT SUN OCT 18 2015
The continued warming trend should extend into Tuesday in advance of
the approaching upper low moving into the desert sw/southern Rockies
region. GFS MOS indicated low to mid 80s possible which at this
point is a good 15 degrees or more above normal highs. The system
has been modeled for several runs now as a closed low weakening to a
mid tropospheric open wave moving into the central and southern
Plains around Thursday. Highest pops starts about Thursday
morning and last through Thursday night/early Friday. With the
initial advance of cloudiness and possible showers and
thunderstorms Wednesday along the warm conveyor belt/mid level
baroclinic zone intersection, forecast high temperatures are cut
10 to 15 degrees in Wednesday. Highs may be relegated to the 60s
and 70s for the remainder of the week.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z Monday MORNING)
ISSUED AT 600 AM CDT SUN OCT 18 2015
Gusty south winds of 20 to near 25 knots will develop by the early
afternoon as 35 to 45 knots winds located in the 900mb to 850mb
level mixes down to the surface. These very windy conditions are
expected to fall back into the 15 to 20 knot range after sunset.
06z NAM BUFR Moisture profiles along with the latest RAP and HRRR
indicate VFR conditions today and tonight.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 79 54 80 59 / 0 0 0 0
GCK 80 54 83 58 / 0 0 0 0
EHA 78 54 80 56 / 0 0 0 0
LBL 80 54 80 58 / 0 0 0 0
HYS 80 55 82 60 / 0 0 0 10
P28 78 53 79 58 / 0 0 0 0
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Russell
LONG TERM...Russell
AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS GOODLAND KS
145 AM MDT SUN OCT 18 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 137 PM MDT SAT OCT 17 2015
EARLY AFTERNOON WV IMAGERY AND RAP ANALYSIS INDICATED LONGWAVE
TROUGH ACROSS THE EASTERN US WITH RIDGING ACROSS THE PLAINS AND
INTO THE NORTHERN ROCKIES. A CLOSED UPPER LOW IS OFF THE NORTHERN
CALIFORNIA COAST. SURFACE LOW PRESSURE HAS DEVELOPED OVER NORTH
CENTRAL COLORADO WITH TIGHT SOUTHERLY GRADIENT ACROSS THE PLAINS
RESPONSIBLE FOR BREEZY-WINDY CONDITIONS ACROSS OUR CWA.
TONIGHT-SUNDAY...CLOSED LOW OFF PACIFIC NW WILL SHIFT TOWARDS THE
GREAT BASIN AND WITH A WEAKER SHORTWAVE TROUGH ROTATING AROUND
NORTHERN EDGE OF UPPER RIDGE INTO THE NORTHERN PLAINS. WEAK
FORCING WILL BE RESPONSIBLE FOR PERIODS OF HIGH CLOUD COVER
OTHERWISE A DEEP DRY LAYER IN PLACE WILL PREVENT PRECIP
DEVELOPMENT IN OUR CWA THROUGH SUNDAY AFTERNOON. LEE TROUGH WILL
SHIFT EAST OVER OUR CWA WITH INCREASING WAA AND UNSEASONABLY WARM
TEMPERATURES RETURNING. BASED ON MIXING HEIGHTS/TEMPS ALOFT WE
SHOULD SEE HIGHS AROUND 80F WHICH IS ABOUT 15F ABOVE NORMAL
SUNDAY. LOWS TONIGHT WILL BE TRICKY AS A RESULT OF A MODERATELY
STRONG LLJ INCREASING BL MIXING...HOWEVER LOCATIONS IN THE NORTH
AND ALONG VALLEYS SHOULD STILL BE ABLE TO DECOUPLE AND COOL TO
AROUND 40F.
WE MAY ALSO SEE A PERIOD OF LIGHT FOG DEVELOP ALONG VALLEYS/LOW
AREAS IN OUR NW ALONG SURFACE TROUGH AS LOW LEVEL MOISTURE
INCREASES. CONFIDENCE WAS TOO LOW AT THIS TIME TO INCLUDE MENTION
DUE TO EXPECTED MIXING...BUT WE WILL NEED TO MONITOR.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 142 AM MDT SUN OCT 18 2015
THE EXTENDED PERIOD BEGINS WITH THE APPROACH OF A CUT OFF AREA OF
LOW PRESSURE AND ASSOCIATED SLIGHTLY NEGATIVE TROUGH. THIS LOW WILL
MOVE NORTHEASTWARD THROUGH THE DAY ON WEDNESDAY AND INTO EARLY
THURSDAY. GUIDANCE IS IN GOOD AGREEMENT WITH REGARDS TO THE LOW
OPENING AND BECOMING A PART OF THE MAIN TROUGH HOWEVER TEMPORAL
AGREEMENT IS WEAK. POPS ON WEDNESDAY WILL BE IN THE 30 TO 50 PERCENT
RANGE NORTH TO SOUTH AS THE SOUTHERN PORTION OF THE CWA WILL HAVE
SLIGHTLY BETTER OMEGA VALUES THANKS TO FAVORABLE POSITIONING OF THE
JET. THIS AXIS WILL SHIFT NORTH AS WE HEAD INTO THURSDAY WITH MUCH
OF THE CWA NOW POTENTIALLY SEEING 40 TO 60 PERCENT POPS ESPECIALLY
DURING THE MIDDAY TO EARLY AFTERNOON HOURS. THE SYSTEM WILL SLOWLY
MOVE OFF TO THE NORTH AND EAST EARLY FRIDAY WITH SHOWERS AND
EMBEDDED THUNDERSTORMS TAPERING OFF FROM WEST TO EAST DURING THE
DAY. THE EASTERN PORTIONS OF THE CWA WILL SEE RAIN CHANCES PERSIST
INTO SATURDAY MORNING HOWEVER MOST ACTIVITY WILL WIND DOWN JUST
BEFORE SUNRISE. THERE IS A POSSIBILITY FOR LOW VISIBILITIES DUE TO
MIST OR FOG ON WEDNESDAY... THURSDAY AND FRIDAY MORNING DUE TO NEAR
ZERO DEW POINT DEPRESSIONS AND A FAVORABLE WIND STRUCTURE.
TEMPERATURES DURING THE FORECAST PERIOD WILL BE NEAR TO SLIGHTLY ABOVE
AVERAGE WITH HIGHS IN THE LOWER 60S AND LOWS IN THE LOW TO MID 40S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1120 PM MDT SAT OCT 17 2015
VFR CONDITIONS WILL CONTINUE AT KGLD AND KMCK FOR THE NEXT 24
HOURS AS HIGH PRESSURE RESIDES OVER THE AREA. SOUTH WINDS WILL
BECOME GUSTY SUNDAY AFTERNOON IN RESPONSE TO A SURFACE TROUGH
OVER EASTERN COLORADO.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...TL
AVIATION...FS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1123 PM MDT SAT OCT 17 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 137 PM MDT SAT OCT 17 2015
EARLY AFTERNOON WV IMAGERY AND RAP ANALYSIS INDICATED LONGWAVE
TROUGH ACROSS THE EASTERN US WITH RIDGING ACROSS THE PLAINS AND
INTO THE NORTHERN ROCKIES. A CLOSED UPPER LOW IS OFF THE NORTHERN
CALIFORNIA COAST. SURFACE LOW PRESSURE HAS DEVELOPED OVER NORTH
CENTRAL COLORADO WITH TIGHT SOUTHERLY GRADIENT ACROSS THE PLAINS
RESPONSIBLE FOR BREEZY-WINDY CONDITIONS ACROSS OUR CWA.
TONIGHT-SUNDAY...CLOSED LOW OFF PACIFIC NW WILL SHIFT TOWARDS THE
GREAT BASIN AND WITH A WEAKER SHORTWAVE TROUGH ROTATING AROUND
NORTHERN EDGE OF UPPER RIDGE INTO THE NORTHERN PLAINS. WEAK
FORCING WILL BE RESPONSIBLE FOR PERIODS OF HIGH CLOUD COVER
OTHERWISE A DEEP DRY LAYER IN PLACE WILL PREVENT PRECIP
DEVELOPMENT IN OUR CWA THROUGH SUNDAY AFTERNOON. LEE TROUGH WILL
SHIFT EAST OVER OUR CWA WITH INCREASING WAA AND UNSEASONABLY WARM
TEMPERATURES RETURNING. BASED ON MIXING HEIGHTS/TEMPS ALOFT WE
SHOULD SEE HIGHS AROUND 80F WHICH IS ABOUT 15F ABOVE NORMAL
SUNDAY. LOWS TONIGHT WILL BE TRICKY AS A RESULT OF A MODERATELY
STRONG LLJ INCREASING BL MIXING...HOWEVER LOCATIONS IN THE NORTH
AND ALONG VALLEYS SHOULD STILL BE ABLE TO DECOUPLE AND COOL TO
AROUND 40F.
WE MAY ALSO SEE A PERIOD OF LIGHT FOG DEVELOP ALONG VALLEYS/LOW
AREAS IN OUR NW ALONG SURFACE TROUGH AS LOW LEVEL MOISTURE
INCREASES. CONFIDENCE WAS TOO LOW AT THIS TIME TO INCLUDE MENTION
DUE TO EXPECTED MIXING...BUT WE WILL NEED TO MONITOR.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 116 PM MDT SAT OCT 17 2015
THE CENTRAL HIGH PLAINS WILL BE UNDER SOUTHWESTERLY TO SOUTHERLY
FLOW ALOFT THE ENTIRE LONG PERIOD AHEAD OF A SLOW MOVING TROUGH
SET TO MOVE OUT OF THE DESERT SOUTHWEST LATE IN THE WEEK. THE
LOWER LEVELS WILL GRADUALLY MOISTEN WITH THE FIRST CHANCE OF
PRECIPITATION OCCURRING TUESDAY NIGHT MAINLY SOUTH OF THE
INTERSTATE THEN SPREADING OVER THE REST OF THE AREA ON WEDNESDAY.
RAIN CHANCES WILL CONTINUE THROUGH THE END OF THE PERIOD WITH A
SERIES OF DISTURBANCES EJECTING OUT OF THE SOUTHWEST. MODELS
SUGGEST AREAS OF HEAVY RAIN POSSIBLE THURSDAY THROUGH THURSDAY
NIGHT AS THE MAIN LIFT MOVES OVER THE AREA. THE CLOUDS AND
PRECIPITATION WILL ALSO RESULT IN COOLER TEMPERATURES FOR THE END
OF THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1120 PM MDT SAT OCT 17 2015
VFR CONDITIONS WILL CONTINUE AT KGLD AND KMCK FOR THE NEXT 24
HOURS AS HIGH PRESSURE RESIDES OVER THE AREA. SOUTH WINDS WILL
BECOME GUSTY SUNDAY AFTERNOON IN RESPONSE TO A SURFACE TROUGH
OVER EASTERN COLORADO.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...024
AVIATION...FS
AREA FORECAST DISCUSSION
NWS JACKSON KY
1047 PM EDT MON OCT 19 2015
.UPDATE...
ISSUED AT 1047 PM EDT MON OCT 19 2015
VALLEY TEMPS ARE DROPPING QUICKLY THIS EVENING...AND HAVE LOWERED
THE MIN TEMP FORECAST TO ALLOW FOR COLDER READINGS IN OUR EASTERN
VALLEYS.
UPDATE ISSUED AT 742 PM EDT MON OCT 19 2015
MADE MINOR UPDATES TO THE GRIDDED FORECAST IN LIGHT OF RECENT
OBS...BUT WITHOUT ANY SUBSTANTIVE CHANGE TO THE FORECAST.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 320 PM EDT MON OCT 19 2015
18Z SFC ANALYSIS SHOWS HIGH PRESSURE JUST EAST OF KENTUCKY WITH A
RELATIVELY LOOSE GRADIENT ACROSS EASTERN KENTUCKY...BUT TIGHTER AS
YOU GO NORTHWEST TOWARD MUCH LOWER PRESSURE. THIS HIGH HAS KEPT
THE SKIES CLEAR TODAY AND WITH PLENTY OF SUNSHINE READINGS HAVE
CLIMBED INTO THE LOW AND MID 60S. MEANWHILE...DEW POINTS HAVE
MIXED DOWN INTO THE UPPER 20S AND LOWER 30S YIELDING HUMIDITIES
DOWN IN THE 20 TO 25 PERCENT RANGE ACROSS PARTS OF EASTERN
KENTUCKY. ALTHOUGH THE HIGH IS KEEPING WINDS RELATIVELY
LIGHT...THE DEEP MIXING IS BRINGING DOWN SOME OCCASIONAL SOUTH
SOUTHWEST GUSTS TO BETWEEN 10 AND 15 MPH.
THE MODELS CONTINUE TO BE IN EXCELLENT AGREEMENT THROUGH THE SHORT
TERM AS THEY ALL DEPICT FLAT AND BROAD RIDGING SPREADING OVER THE
REGION INTO WEDNESDAY MORNING. ONLY WEAK ENERGY WILL DRIFT PAST
EASTERN KENTUCKY AMID THOSE HIGHER HEIGHTS. THE PATTERN DOES
START TO CHANGE AFTER THE SHORT TERM WITH A DEVELOPING NORTHERN
STREAM TROUGH MOVING EAST ALONG THE INTERNATIONAL BORDER INTO
WESTERN ONTARIO. AGAIN FAVORED THE HRRR AND NAM12 FOR WEATHER
DETAILS GIVEN THE MODEL AGREEMENT THROUGH WEDNESDAY MORNING.
SENSIBLE WEATHER WILL FEATURE ANOTHER CLEAR NIGHT WITH GOOD
RADIATIONAL COOLING. THIS WILL RESULT IN A FAIRLY LARGE RIDGE TO
VALLEY TEMPERATURE SPLIT. AGAIN...SOME PATCHY FOG WILL BE FOUND IN
THE VALLEYS TOWARDS DAWN. FOR TUESDAY AND TUESDAY NIGHT CONDITIONS
WILL BE SIMILAR TO THE PAST 24 HOURS WITH WARMER TEMPERATURES
GIVEN THE MODERATING HIGH DEPARTING THE AREA. ACCORDINGLY...HIGH
TEMPERATURES ON TUESDAY WILL BE ANOTHER 5 DEGREES OR SO HIGHER
THAN TODAY WITH SIMILAR LOW RH CONCERNS. WINDS WILL PICK UP A BIT
MORE...AS WELL...RUNNING FROM THE SOUTHWEST AT AROUND 10 MPH WITH
SOME HIGHER GUSTS. WILL HIGHLIGHT THIS LOW RH AND INCREASING WIND
CONCERN IN THE HWO. TEMPERATURES WILL BE A BIT MILDER TUESDAY
NIGHT WITH STILL A LARGE RIDGE AND VALLEY TEMPERATURE SPLIT
ANTICIPATED...ALONG WITH PATCHY VALLEY FOG NEAR DAWN.
AGAIN STARTED WITH THE SHORTBLEND GUIDANCE FOR THE T AND TD GRIDS
INTO TUESDAY MORNING FOLLOWED BY THE SUPERBLEND. DID MAKE SOME
SIGNIFICANT CHANGES TO THE T GRIDS TONIGHT AND TUESDAY NIGHT TO
ACCOUNT FOR THE ANTICIPATED RIDGE AND VALLEY DIFFERENCES. AS FOR
POPS...ONCE AGAIN ZEROED THEM OUT THROUGH THE SHORT TERM PERIOD...
IN LINE WITH ALL GUIDANCE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 240 PM EDT MON OCT 19 2015
HIGH PRESSURE WILL HOLD OVER KENTUCKY THROUGH MUCH OF THE
WEEK...PROVIDING A PLEASANT STRETCH OF MILD WEATHER. STILL
WATCHING FOR SOME VERY LOW RELATIVE HUMIDITIES INTO WEDNESDAY
AFTERNOON. WINDS SHOULD STAY IN THE 5 TO 10 MPH RANGE...BUT GIVEN
THE DRY CONDITIONS LEADING UP TO WEDNESDAY...ANY WIND COULD POSE
A FIRE DANGER. PLAN TO HIGHLIGHT THIS THREAT IN THE HWO.
A COLD FRONT WILL WASH OUT AS IT DROPS SOUTH INTO NORTHERN
KENTUCKY ON THURSDAY...BUT THIS FEATURE WILL REMAIN MOISTURE
STARVED AND POSE NO THREAT TO OUR WEATHER OUTSIDE A SLIGHT UPTICK
IN SKY COVER. HIGH PRESSURE WILL BUILD BACK IN BY FRIDAY AND
CONTINUE INTO SATURDAY.
ATTENTION WILL THEN TURN TO A COUPLE OF DISTURBANCES AS WE HEAD
THROUGH NEXT WEEKEND. A NORTHERN STREAM SHORTWAVE WILL PUSH EAST
ACROSS THE NORTH CENTRAL PLAINS...WITH A SOUTH WAVE CROSSING TEXAS
ON SATURDAY. WHILE ITS STILL UNCERTAIN HOW THESE TWO WAVES WILL
INTERACT AS THEY MOVE EAST...IT DOES APPEAR THESE WAVES WILL HELP
PUSH A COLD FRONT ACROSS THE AREA SATURDAY NIGHT INTO SUNDAY. GOOD
MOISTURE TRANSPORT OFF THE GULF OF MEXICO...SHOULD PROMOTE DECENT
RAIN CHANCES AS THIS BOUNDARY MOVES ACROSS KENTUCKY. MODELS ARE
COMING INTO AGREEMENT ON BEST RAIN CHANCES COMING LATE SATURDAY
NIGHT THROUGH SUNDAY. FOR THIS REASON...POPS HAVE BEEN TRENDED
UPWARDS FOR THESE TWO PERIODS. THE FRONT COULD HANG UP OVER THE
AREA INTO EARLY NEXT WEEK...KEEPING THE WEATHER SOMEWHAT
UNSETTLED. ANY RAIN WILL BE WELCOME AFTER THE EXTENDED STRETCH OF
DRY WEATHER...AND SHOULD HOPEFULLY HELP BRING A TEMPORARY END TO
ANY FIRE DANGER.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 742 PM EDT MON OCT 19 2015
DENSE FOG WILL AFFECT SOME DEEP VALLEY LOCATIONS AROUND LARGE
STREAMS NEAR DAWN...BUT IT IS UNLIKELY TO IMPACT TAF SITES.
OTHERWISE...VFR CONDITIONS WITH LIGHT WINDS WILL PREVAIL.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...GREIF
LONG TERM...KAS
AVIATION...HAL
AREA FORECAST DISCUSSION...CORRECTED
NWS JACKSON KY
742 PM EDT MON OCT 19 2015
.UPDATE...
ISSUED AT 742 PM EDT MON OCT 19 2015
MADE MINOR UPDATES TO THE GRIDDED FORECAST IN LIGHT OF RECENT
OBS...BUT WITHOUT ANY SUBSTANTIVE CHANGE TO THE FORECAST.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 320 PM EDT MON OCT 19 2015
18Z SFC ANALYSIS SHOWS HIGH PRESSURE JUST EAST OF KENTUCKY WITH A
RELATIVELY LOOSE GRADIENT ACROSS EASTERN KENTUCKY...BUT TIGHTER AS
YOU GO NORTHWEST TOWARD MUCH LOWER PRESSURE. THIS HIGH HAS KEPT
THE SKIES CLEAR TODAY AND WITH PLENTY OF SUNSHINE READINGS HAVE
CLIMBED INTO THE LOW AND MID 60S. MEANWHILE...DEW POINTS HAVE
MIXED DOWN INTO THE UPPER 20S AND LOWER 30S YIELDING HUMIDITIES
DOWN IN THE 20 TO 25 PERCENT RANGE ACROSS PARTS OF EASTERN
KENTUCKY. ALTHOUGH THE HIGH IS KEEPING WINDS RELATIVELY
LIGHT...THE DEEP MIXING IS BRINGING DOWN SOME OCCASIONAL SOUTH
SOUTHWEST GUSTS TO BETWEEN 10 AND 15 MPH.
THE MODELS CONTINUE TO BE IN EXCELLENT AGREEMENT THROUGH THE SHORT
TERM AS THEY ALL DEPICT FLAT AND BROAD RIDGING SPREADING OVER THE
REGION INTO WEDNESDAY MORNING. ONLY WEAK ENERGY WILL DRIFT PAST
EASTERN KENTUCKY AMID THOSE HIGHER HEIGHTS. THE PATTERN DOES
START TO CHANGE AFTER THE SHORT TERM WITH A DEVELOPING NORTHERN
STREAM TROUGH MOVING EAST ALONG THE INTERNATIONAL BORDER INTO
WESTERN ONTARIO. AGAIN FAVORED THE HRRR AND NAM12 FOR WEATHER
DETAILS GIVEN THE MODEL AGREEMENT THROUGH WEDNESDAY MORNING.
SENSIBLE WEATHER WILL FEATURE ANOTHER CLEAR NIGHT WITH GOOD
RADIATIONAL COOLING. THIS WILL RESULT IN A FAIRLY LARGE RIDGE TO
VALLEY TEMPERATURE SPLIT. AGAIN...SOME PATCHY FOG WILL BE FOUND IN
THE VALLEYS TOWARDS DAWN. FOR TUESDAY AND TUESDAY NIGHT CONDITIONS
WILL BE SIMILAR TO THE PAST 24 HOURS WITH WARMER TEMPERATURES
GIVEN THE MODERATING HIGH DEPARTING THE AREA. ACCORDINGLY...HIGH
TEMPERATURES ON TUESDAY WILL BE ANOTHER 5 DEGREES OR SO HIGHER
THAN TODAY WITH SIMILAR LOW RH CONCERNS. WINDS WILL PICK UP A BIT
MORE...AS WELL...RUNNING FROM THE SOUTHWEST AT AROUND 10 MPH WITH
SOME HIGHER GUSTS. WILL HIGHLIGHT THIS LOW RH AND INCREASING WIND
CONCERN IN THE HWO. TEMPERATURES WILL BE A BIT MILDER TUESDAY
NIGHT WITH STILL A LARGE RIDGE AND VALLEY TEMPERATURE SPLIT
ANTICIPATED...ALONG WITH PATCHY VALLEY FOG NEAR DAWN.
AGAIN STARTED WITH THE SHORTBLEND GUIDANCE FOR THE T AND TD GRIDS
INTO TUESDAY MORNING FOLLOWED BY THE SUPERBLEND. DID MAKE SOME
SIGNIFICANT CHANGES TO THE T GRIDS TONIGHT AND TUESDAY NIGHT TO
ACCOUNT FOR THE ANTICIPATED RIDGE AND VALLEY DIFFERENCES. AS FOR
POPS...ONCE AGAIN ZEROED THEM OUT THROUGH THE SHORT TERM PERIOD...
IN LINE WITH ALL GUIDANCE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 240 PM EDT MON OCT 19 2015
HIGH PRESSURE WILL HOLD OVER KENTUCKY THROUGH MUCH OF THE
WEEK...PROVIDING A PLEASANT STRETCH OF MILD WEATHER. STILL
WATCHING FOR SOME VERY LOW RELATIVE HUMIDITIES INTO WEDNESDAY
AFTERNOON. WINDS SHOULD STAY IN THE 5 TO 10 MPH RANGE...BUT GIVEN
THE DRY CONDITIONS LEADING UP TO WEDNESDAY...ANY WIND COULD POSE
A FIRE DANGER. PLAN TO HIGHLIGHT THIS THREAT IN THE HWO.
A COLD FRONT WILL WASH OUT AS IT DROPS SOUTH INTO NORTHERN
KENTUCKY ON THURSDAY...BUT THIS FEATURE WILL REMAIN MOISTURE
STARVED AND POSE NO THREAT TO OUR WEATHER OUTSIDE A SLIGHT UPTICK
IN SKY COVER. HIGH PRESSURE WILL BUILD BACK IN BY FRIDAY AND
CONTINUE INTO SATURDAY.
ATTENTION WILL THEN TURN TO A COUPLE OF DISTURBANCES AS WE HEAD
THROUGH NEXT WEEKEND. A NORTHERN STREAM SHORTWAVE WILL PUSH EAST
ACROSS THE NORTH CENTRAL PLAINS...WITH A SOUTH WAVE CROSSING TEXAS
ON SATURDAY. WHILE ITS STILL UNCERTAIN HOW THESE TWO WAVES WILL
INTERACT AS THEY MOVE EAST...IT DOES APPEAR THESE WAVES WILL HELP
PUSH A COLD FRONT ACROSS THE AREA SATURDAY NIGHT INTO SUNDAY. GOOD
MOISTURE TRANSPORT OFF THE GULF OF MEXICO...SHOULD PROMOTE DECENT
RAIN CHANCES AS THIS BOUNDARY MOVES ACROSS KENTUCKY. MODELS ARE
COMING INTO AGREEMENT ON BEST RAIN CHANCES COMING LATE SATURDAY
NIGHT THROUGH SUNDAY. FOR THIS REASON...POPS HAVE BEEN TRENDED
UPWARDS FOR THESE TWO PERIODS. THE FRONT COULD HANG UP OVER THE
AREA INTO EARLY NEXT WEEK...KEEPING THE WEATHER SOMEWHAT
UNSETTLED. ANY RAIN WILL BE WELCOME AFTER THE EXTENDED STRETCH OF
DRY WEATHER...AND SHOULD HOPEFULLY HELP BRING A TEMPORARY END TO
ANY FIRE DANGER.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 742 PM EDT MON OCT 19 2015
DENSE FOG WILL AFFECT SOME DEEP VALLEY LOCATIONS AROUND LARGE
STREAMS NEAR DAWN...BUT IT IS UNLIKELY TO IMPACT TAF SITES.
OTHERWISE...VFR CONDITIONS WITH LIGHT WINDS WILL PREVAIL.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...GREIF
LONG TERM...KAS
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS JACKSON KY
310 PM EDT SUN OCT 18 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 310 PM EDT SUN OCT 18 2015
18Z SFC ANALYSIS SHOWS HIGH PRESSURE SETTLING INTO THE OHIO VALLEY
AND KENTUCKY. THIS HAS KEPT THE CLOUDS AT BAY TODAY AND ALSO THE
WINDS LIGHT. THE DRIER AIR ALOFT DID MIX DOWN BETTER THIS
AFTERNOON THAN YESTERDAY WITH READINGS FALLING INTO THE LOWER AND
MIDDLE 20S. WHEN COMBINED WITH TEMPERATURES GENERALLY IN THE MID
AND UPPER 50S RH VALUES HAVE FALLEN INTO THE LOW 30S FOR MUCH OF
THE AREA. THE DRY AIR WILL ALSO SERVE WELL FOR A QUICK TEMPERATURE
DROP OFF THIS EVENING...ESPECIALLY IN THE VALLEYS.
THE MODELS CONTINUE TO BE IN EXCELLENT AGREEMENT ALOFT THROUGH THE
SHORT TERM AS A BROAD AND FLATTENING RIDGE EASES INTO THE REGION
IN THE WAKE OF THE TROUGH CROSSING THE NORTHEAST. SOME WEAK ENERGY
WILL DRIFT THROUGH THE AREA ON MONDAY...BUT IN A RISING HEIGHT
ENVIRONMENT THIS WILL BE NEGLIGIBLE. HAVE FOLLOWED THE HIGHER
RESOLUTION NAM12 AND HRRR FOR WX DETAILS GIVEN THE MODEL AGREEMENT
WHILE ALSO FAVORING THE GFS CO-OP MOS...TO A CERTAIN EXTENT...FOR
SITE SPECIFIC LOWS TONIGHT AND MONDAY NIGHT.
SENSIBLE WEATHER WILL FEATURE ANOTHER CHILLY NIGHT WITH A LARGER
RIDGE TO VALLEY SPLIT DEVELOPING AROUND SUNSET AND CONTINUING
THROUGH THE NIGHT. THIS WILL RESULT IN SUB-FREEZING TEMPERATURES
FOR THE VALLEYS BY DAWN ALONG WITH WIDESPREAD FROST. AS A
RESULT...WE WILL CONTINUE OUR FREEZE WARNING THROUGH 9 AM MONDAY
MORNING. IN ADDITION...DO ANTICIPATE ANOTHER BATCH OF PATCHY DENSE
FOG ALONG THE RIVERS AND LAKES ACROSS THE CWA TOWARD DAWN. WITH
THE MODERATING SFC HIGH DOMINATING THE WX SUNNY SKIES WILL BE THE
RULE FOR MONDAY ALONG WITH WARMER TEMPERATURES UP INTO THE 60S FOR
HIGHS. MONDAY NIGHT WILL BE MILDER AS THE HIGH STARTS TO PULL AWAY
OPENING UP A LARGER RIDGE TO VALLEY SPLIT BUT ALSO TEMPERATURES 5
TO 10 DEGREES HIGHER ACROSS THE BOARD FOR LOWS. PATCHY FOG WILL
ALSO BE FOUND ALONG THE RIVER VALLEYS MONDAY MORNING.
STARTED WITH THE SHORTBLEND GUIDANCE FOR THE T AND TD GRIDS INTO
MONDAY MORNING FOLLOWED BY THE SUPERBLEND. DID MAKE SOME
SIGNIFICANT CHANGES TO THE T GRIDS TONIGHT AND MONDAY NIGHT TO
ACCOUNT FOR THE ANTICIPATED RIDGE TO VALLEY DIFFERENCES. AS FOR
POPS...ONCE AGAIN ZEROED THEM OUT THROUGH THE SHORT TERM
PERIOD...IN LINE WITH ALL GUIDANCE.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 215 PM EDT SUN OCT 18 2015
HIGH PRESSURE WILL CONTINUE TO DOMINATE THE WEATHER THROUGH THE
EXTENDED PORTION OF THE FORECAST WITH NO RAIN EXPECTED. HIGHS WILL
REMAIN AT OR ABOVE 70 THROUGH THE WEEK AND INTO NEXT WEEKEND.
THE MAIN WEATHER IMPACT FOR THIS WEEK WILL BE THE CONTINUATION OF
DRY CONDITIONS ON TUESDAY AND WEDNESDAY...WITH AFTERNOON RH VALUES
FALLING TO BETWEEN 20 AND 30 PERCENT. SOME SPOTS COULD SEE RH`S INTO
THE TEENS. RH WILL RECOVER SLIGHTLY ON THURSDAY. HOWEVER...AS THE
RIDGE BUILDS AGAIN FRIDAY AND SATURDAY...MORE LOW RH`S COULD RETURN.
WILL CONTINUE TO HIGHLIGHT THE LOW AFTERNOON RELATIVE HUMIDITIES IN
THE FIRE WEATHER FORECAST. FORTUNATELY...THE GRADIENT SHOULD REMAIN
WEAK ENOUGH TO LIMIT OVERALL WIND POTENTIAL THROUGH THE
WEEK...KEEPING WINDS UNDER 10 MPH.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 210 PM EDT SUN OCT 18 2015
HIGH PRESSURE WILL REMAIN FIRMLY IN CONTROL OF THE WEATHER
THROUGH THE UPCOMING TAF PERIOD. THIS WILL KEEP ALL TAF SITES VFR
INTO MONDAY AFTERNOON. THIS HIGH PRESSURE WILL ALSO KEEP WINDS
LIGHT THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 3 AM TO 9 AM EDT MONDAY FOR KYZ044-050>052-
058>060-068-069-079-080-083>088-104-106>120.
&&
$$
SHORT TERM...GREIF
LONG TERM...KAS
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS JACKSON KY
106 AM EDT SUN OCT 18 2015
.UPDATE...
ISSUED AT 106 AM EDT SUN OCT 18 2015
HIGH PRESSURE CONTINUES TO WORK INTO THE OHIO AND TENNESSEE VALLEY
REGIONS THIS LATE NIGHT HOUR. THIS CANADIAN HIGH PRESSURE COUPLED
WITH CLEAR SKIES HAS ALLOWED FOR DECOUPLING IN MOST VALLEY
LOCATIONS. TEMPS THIS HOUR ARE ALREADY NEAR TO BELOW FREEZING IN
SUSPECTED VALLEY LOCALES. THEREFORE DID DROP OFF TEMPS A BIT
QUICKER THAN WHAT WAS PREVIOUSLY IN THE GRIDS...BUT FOR THE MOST
PART NO MAJOR CHANGES NEEDED THIS UPDATE.
UPDATE ISSUED AT 830 PM EDT SAT OCT 17 2015
HIGH PRESSURE CENTERED OVER THE MID MS VALLEY CONTINUES TO
GRADUALLY SHIFT EAST INTO THE OH VALLEY REGION AND HAS USHERED IN
A RELATIVELY COLD AND DRY AIRMASS FOR MID OCTOBER. A DISTURBANCE
PASSING BY TO THE NORTHEAST HAS LED TO SOME STRATOCU AROUND 6KFT
ACROSS THE EASTERN HALF OF THE AREA. HOWEVER...THE BACK EDGE OF
THESE APPEAR TO BE OVER INDIANA...AND VALLEY LOCATIONS HAVE
ALREADY DECOUPLED. THIS AND DEWPOINTS IN THE UPPER 20S TO AROUND
30 WILL SET THE STAGE FOR A HARD FREEZE IN MANY VALLEY LOCATIONS.
OTHER THAN SOME SLIGHT ADJUSTMENTS TO HOURLY GRIDS...NO CHANGES
WERE NEEDED ATTM.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 200 PM EDT SAT OCT 17 2015
17Z SFC ANALYSIS SHOWS HIGH PRESSURE SETTLING INTO THE MID
MISSISSIPPI VALLEY WITH ITS INFLUENCE STRETCHING WELL EAST INTO
THE OHIO VALLEY. THIS HAS LED TO A DRY AIR MASS OVER EASTERN
KENTUCKY ALONG WITH AMPLE MORNING SUNSHINE. THESE FACTORS
CONTRIBUTED TO TEMPERATURES REBOUNDING INTO THE MIDDLE AND UPPER
50S BY EARLY THIS AFTERNOON. DEVELOPING CU TO THE NORTH WILL
LIMIT ADDITIONAL HEATING THERE...BUT THE SOUTH COULD RISE ANOTHER
COUPLE OF DEGREES FOR HIGHS. DEWPOINTS...MEANWHILE...ARE IN THE
UPPER 20S AND LOWER 30S YIELDING RH VALUES DOWN NEAR 30 PERCENT
IN THE SOUTH AND CLOSER TO 40 PERCENT NORTH. WINDS HAVE BEEN
GENERALLY OUT OF THE NORTH AT 5 TO 10 MPH.
THE MODELS REMAIN IN EXCELLENT AGREEMENT ALOFT THROUGH THE SHORT
TERM PORTION OF THE FORECAST AS THEY ALL GRADUALLY MOVE A BROAD
AND RELATIVELY DEEP TROUGH THE NORTHEASTERN PARTS OF NORTH
AMERICA. IN THE WAKE OF THIS TROUGH DEPARTING THE OHIO VALLEY...
HEIGHTS WILL RISE OVER KENTUCKY SUNDAY INTO MONDAY MORNING. GIVEN
THIS AGREEMENT HAVE FOLLOWED THE WEATHER DETAILS...FEW THAT THERE
ARE...FROM THE HRRR AND NAM12. DID AGAIN LEAN HEAVILY ON THE GFS
BASED COOP MOS TO HELP HIT OUR VALLEY COLD SPOTS TONIGHT AND
SUNDAY NIGHT.
SENSIBLE WEATHER WILL FEATURE A COLD NIGHT UNDER MOSTLY CLEAR
SKIES...ONCE THE NORTHERN CU FADES AROUND SUNSET. GOOD RADIATIONAL
COOLING UNDER THE INVERSION WILL RESULT IN VALLEY TEMPS FALLING
INTO THE MIDDLE 20S WHILE RIDGES SETTLE INTO THE LOWER 30S. THESE
LOW TEMPS WILL WARRANT A FREEZE WARNING WITH THE POTENTIAL TO END
THE GROWING SEASON THROUGHOUT THE CWA...IN ADDITION TO ANTICIPATED
WIDESPREAD FROST. PATCHY DENSE FOG IN THE RIVER VALLEYS IS ALSO
LIKELY TO FORM GIVEN WHAT WE SAW THIS MORNING. AFTER COORDINATION
WITH THE UK AG WX CENTER YESTERDAY WILL CONTINUE FROST/FREEZE
HEADLINES INTO MONDAY MORNING REGARDLESS OF HOW COLD IT GETS
TONIGHT. FOLLOWING ANOTHER COOL DAY ON SUNDAY...CONDITIONS SIMILAR
TO TONIGHT WILL SET THE STAGE FOR ANOTHER ROUND OF FREEZING
TEMPERATURES IN THE VALLEYS...ESPECIALLY THE EASTERN ONES. SO...
THIS NECESSITATES ANOTHER FREEZE WARNING FOR LATE SUNDAY NIGHT
INTO MONDAY MORNING. AGAIN FROST WILL BE PREVALENT THROUGHOUT THE
AREA ALONG WITH PATCHY FOG IN THE RIVER VALLEYS.
AGAIN USED THE SHORTBLEND GUIDANCE AS A STARTING POINT FOR THE T
AND TD GRIDS INTO SUNDAY MORNING WITH THE SUPERBLEND USED
THEREAFTER. DID MAKE SOME SIGNIFICANT CHANGES TO THE T GRIDS
TONIGHT AND SUNDAY NIGHT TO ACCOUNT FOR THE ANTICIPATED RIDGE TO
VALLEY DIFFERENCES. AS FOR POPS...AGAIN WENT ZERO THROUGH THE
SHORT TERM PERIOD...IN LINE WITH ALL GUIDANCE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 200 PM EDT SAT OCT 17 2015
HIGH PRESSURE WILL DOMINATE THROUGH THE EXTENDED PORTION OF THE
FORECAST...PROVIDING DRY WEATHER AND WARMING TEMPERATURES THROUGH
THE FIRST HALF OF THE UPCOMING WEEK. GIVEN THE DEGREE OF DRY
WEATHER...HAVE OPTED TO TREND TEMPERATURES SLIGHTLY ABOVE GUIDANCE
FOR HIGHS EACH DAY...WHILE STAYING UNDER GUIDANCE FOR LOWS AT
NIGHT...ESPECIALLY IN THE VALLEYS. THIS MEANS WE SHOULD SEE HIGHS
AT OR ABOVE 70 FROM TUESDAY ONWARD...MAKING FOR A VERY PLEASANT
STRETCH OF WEATHER. A WASHED OUT FRONTAL BOUNDARY WILL DROP SOUTH
ACROSS THE AREA ON THURSDAY...BUT THE FEATURE CONTINUES TO TREND
WEAKER...AND WILL LIKELY HAVE MINIMAL IMPACT ON THE WEATHER ACROSS
EASTERN KENTUCKY. HIGH PRESSURE WILL THEN QUICKLY REBUILD AS WE HEAD
INTO NEXT WEEKEND...WITH THE MILD WEATHER CONTINUING INTO NEXT
WEEKEND.
MAIN WEATHER IMPACT WE WILL SEE THIS WEEK...IS THE CONTINUATION OF
THE DRY CONDITIONS WITH AFTERNOON RELATIVE HUMIDITIES FALLING TO
BETWEEN 20 AND 30 PERCENT. ITS LIKELY A FEW RH READINGS INTO THE
TEENS MAY BE POSSIBLE. WILL CONTINUE TO HIGHLIGHT THE LOW AFTERNOON
RELATIVE HUMIDITIES IN THE FIRE WEATHER FORECAST. FORTUNATELY...THE
GRADIENT SHOULD REMAIN WEAK ENOUGH TO LIMIT OVERALL WIND POTENTIAL
THROUGH THE WEEK...KEEPING WINDS UNDER 10 MPH. CONTINUED TO RUN
DEWPOINTS UNDER GUIDANCE EACH AFTERNOON AS MODELS TYPICALLY DON`T
HANDLE DEWPOINTS WELL IN THE AFTERNOON WITH GOOD MIXING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 100 AM EDT SUN OCT 18 2015
HIGH PRESSURE CONTINUES TO KEEP WEATHER QUITE AND THEREFORE VFR
TAFS. WHILE THERE COULD BE SOME PATCHY FOG IN SOME VALLEY
LOCATIONS...HOWEVER TAF SITES ARE EXPECTED TO REMAIN P6SM. WINDS
WILL ALSO REMAIN LIGHT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING UNTIL 9 AM EDT THIS MORNING FOR KYZ044-050>052-
058>060-068-069-079-080-083>088-104-106>120.
FREEZE WARNING FROM 3 AM TO 9 AM EDT MONDAY FOR KYZ044-050>052-
058>060-068-069-079-080-083>088-104-106>120.
&&
$$
UPDATE...DJ
SHORT TERM...GREIF
LONG TERM...KAS
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
100 AM EDT SUN OCT 18 2015
.UPDATE...
ISSUED AT 830 PM EDT SAT OCT 17 2015
HIGH PRESSURE CENTERED OVER THE MID MS VALLEY CONTINUES TO
GRADUALLY SHIFT EAST INTO THE OH VALLEY REGION AND HAS USHERED IN
A RELATIVELY COLD AND DRY AIRMASS FOR MID OCTOBER. A DISTURBANCE
PASSING BY TO THE NORTHEAST HAS LED TO SOME STRATOCU AROUND 6KFT
ACROSS THE EASTERN HALF OF THE AREA. HOWEVER...THE BACK EDGE OF
THESE APPEAR TO BE OVER INDIANA...AND VALLEY LOCATIONS HAVE
ALREADY DECOUPLED. THIS AND DEWPOINTS IN THE UPPER 20S TO AROUND
30 WILL SET THE STAGE FOR A HARD FREEZE IN MANY VALLEY LOCATIONS.
OTHER THAN SOME SLIGHT ADJUSTMENTS TO HOURLY GRIDS...NO CHANGES
WERE NEEDED ATTM.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 200 PM EDT SAT OCT 17 2015
17Z SFC ANALYSIS SHOWS HIGH PRESSURE SETTLING INTO THE MID
MISSISSIPPI VALLEY WITH ITS INFLUENCE STRETCHING WELL EAST INTO
THE OHIO VALLEY. THIS HAS LED TO A DRY AIR MASS OVER EASTERN
KENTUCKY ALONG WITH AMPLE MORNING SUNSHINE. THESE FACTORS
CONTRIBUTED TO TEMPERATURES REBOUNDING INTO THE MIDDLE AND UPPER
50S BY EARLY THIS AFTERNOON. DEVELOPING CU TO THE NORTH WILL
LIMIT ADDITIONAL HEATING THERE...BUT THE SOUTH COULD RISE ANOTHER
COUPLE OF DEGREES FOR HIGHS. DEWPOINTS...MEANWHILE...ARE IN THE
UPPER 20S AND LOWER 30S YIELDING RH VALUES DOWN NEAR 30 PERCENT
IN THE SOUTH AND CLOSER TO 40 PERCENT NORTH. WINDS HAVE BEEN
GENERALLY OUT OF THE NORTH AT 5 TO 10 MPH.
THE MODELS REMAIN IN EXCELLENT AGREEMENT ALOFT THROUGH THE SHORT
TERM PORTION OF THE FORECAST AS THEY ALL GRADUALLY MOVE A BROAD
AND RELATIVELY DEEP TROUGH THE NORTHEASTERN PARTS OF NORTH
AMERICA. IN THE WAKE OF THIS TROUGH DEPARTING THE OHIO VALLEY...
HEIGHTS WILL RISE OVER KENTUCKY SUNDAY INTO MONDAY MORNING. GIVEN
THIS AGREEMENT HAVE FOLLOWED THE WEATHER DETAILS...FEW THAT THERE
ARE...FROM THE HRRR AND NAM12. DID AGAIN LEAN HEAVILY ON THE GFS
BASED COOP MOS TO HELP HIT OUR VALLEY COLD SPOTS TONIGHT AND
SUNDAY NIGHT.
SENSIBLE WEATHER WILL FEATURE A COLD NIGHT UNDER MOSTLY CLEAR
SKIES...ONCE THE NORTHERN CU FADES AROUND SUNSET. GOOD RADIATIONAL
COOLING UNDER THE INVERSION WILL RESULT IN VALLEY TEMPS FALLING
INTO THE MIDDLE 20S WHILE RIDGES SETTLE INTO THE LOWER 30S. THESE
LOW TEMPS WILL WARRANT A FREEZE WARNING WITH THE POTENTIAL TO END
THE GROWING SEASON THROUGHOUT THE CWA...IN ADDITION TO ANTICIPATED
WIDESPREAD FROST. PATCHY DENSE FOG IN THE RIVER VALLEYS IS ALSO
LIKELY TO FORM GIVEN WHAT WE SAW THIS MORNING. AFTER COORDINATION
WITH THE UK AG WX CENTER YESTERDAY WILL CONTINUE FROST/FREEZE
HEADLINES INTO MONDAY MORNING REGARDLESS OF HOW COLD IT GETS
TONIGHT. FOLLOWING ANOTHER COOL DAY ON SUNDAY...CONDITIONS SIMILAR
TO TONIGHT WILL SET THE STAGE FOR ANOTHER ROUND OF FREEZING
TEMPERATURES IN THE VALLEYS...ESPECIALLY THE EASTERN ONES. SO...
THIS NECESSITATES ANOTHER FREEZE WARNING FOR LATE SUNDAY NIGHT
INTO MONDAY MORNING. AGAIN FROST WILL BE PREVALENT THROUGHOUT THE
AREA ALONG WITH PATCHY FOG IN THE RIVER VALLEYS.
AGAIN USED THE SHORTBLEND GUIDANCE AS A STARTING POINT FOR THE T
AND TD GRIDS INTO SUNDAY MORNING WITH THE SUPERBLEND USED
THEREAFTER. DID MAKE SOME SIGNIFICANT CHANGES TO THE T GRIDS
TONIGHT AND SUNDAY NIGHT TO ACCOUNT FOR THE ANTICIPATED RIDGE TO
VALLEY DIFFERENCES. AS FOR POPS...AGAIN WENT ZERO THROUGH THE
SHORT TERM PERIOD...IN LINE WITH ALL GUIDANCE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 200 PM EDT SAT OCT 17 2015
HIGH PRESSURE WILL DOMINATE THROUGH THE EXTENDED PORTION OF THE
FORECAST...PROVIDING DRY WEATHER AND WARMING TEMPERATURES THROUGH
THE FIRST HALF OF THE UPCOMING WEEK. GIVEN THE DEGREE OF DRY
WEATHER...HAVE OPTED TO TREND TEMPERATURES SLIGHTLY ABOVE GUIDANCE
FOR HIGHS EACH DAY...WHILE STAYING UNDER GUIDANCE FOR LOWS AT
NIGHT...ESPECIALLY IN THE VALLEYS. THIS MEANS WE SHOULD SEE HIGHS
AT OR ABOVE 70 FROM TUESDAY ONWARD...MAKING FOR A VERY PLEASANT
STRETCH OF WEATHER. A WASHED OUT FRONTAL BOUNDARY WILL DROP SOUTH
ACROSS THE AREA ON THURSDAY...BUT THE FEATURE CONTINUES TO TREND
WEAKER...AND WILL LIKELY HAVE MINIMAL IMPACT ON THE WEATHER ACROSS
EASTERN KENTUCKY. HIGH PRESSURE WILL THEN QUICKLY REBUILD AS WE HEAD
INTO NEXT WEEKEND...WITH THE MILD WEATHER CONTINUING INTO NEXT
WEEKEND.
MAIN WEATHER IMPACT WE WILL SEE THIS WEEK...IS THE CONTINUATION OF
THE DRY CONDITIONS WITH AFTERNOON RELATIVE HUMIDITIES FALLING TO
BETWEEN 20 AND 30 PERCENT. ITS LIKELY A FEW RH READINGS INTO THE
TEENS MAY BE POSSIBLE. WILL CONTINUE TO HIGHLIGHT THE LOW AFTERNOON
RELATIVE HUMIDITIES IN THE FIRE WEATHER FORECAST. FORTUNATELY...THE
GRADIENT SHOULD REMAIN WEAK ENOUGH TO LIMIT OVERALL WIND POTENTIAL
THROUGH THE WEEK...KEEPING WINDS UNDER 10 MPH. CONTINUED TO RUN
DEWPOINTS UNDER GUIDANCE EACH AFTERNOON AS MODELS TYPICALLY DON`T
HANDLE DEWPOINTS WELL IN THE AFTERNOON WITH GOOD MIXING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 100 AM EDT SUN OCT 18 2015
HIGH PRESSURE CONTINUES TO KEEP WEATHER QUITE AND THEREFORE VFR
TAFS. WHILE THERE COULD BE SOME PATCHY FOG IN SOME VALLEY
LOCATIONS...HOWEVER TAF SITES ARE EXPECTED TO REMAIN P6SM. WINDS
WILL ALSO REMAIN LIGHT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING UNTIL 9 AM EDT THIS MORNING FOR KYZ044-050>052-
058>060-068-069-079-080-083>088-104-106>120.
FREEZE WARNING FROM 3 AM TO 9 AM EDT MONDAY FOR KYZ044-050>052-
058>060-068-069-079-080-083>088-104-106>120.
&&
$$
UPDATE...JP
SHORT TERM...GREIF
LONG TERM...KAS
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
649 PM EDT SUN OCT 18 2015
.SYNOPSIS...
LAKE EFFECT SNOW SHOWERS WILL TAPER OFF THIS EVENING...WITH COLD
TEMPERATURES REMAINING ACROSS THE REGION THROUGH TONIGHT. HIGH
PRESSURE WILL BRING A WARMING TREND MONDAY THROUGH MUCH OF THE
WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
THIS EVENINGS UPDATE WAS MADE TO ADJUST SKY COVER AND POPS BASED
ON THE LATEST RADAR/SATELLITE OBSERVATIONS AND TRENDS. EXPECT THE
SCATTERED RAIN/SNOW SHOWER ACTIVITY TO TAPER OFF AS SUBSIDENCE
LOWERS INVERSIONS...CUTTING OFF THE DEEP SATURATION TO MAINTAIN
LAKE-EFFECT SHOWER ACTIVITY. ADJUSTED POPS BASED ON THE HRRR WHICH
WILL KEEP CHANCE POPS IN NORTH OF I-80 A LITTLE LONGER.
WITH THE SURFACE HIGH BUILDING OVERHEAD...EXPECT CLOUDS TO
DISSIPATE...ALLOWING FOR GOOD RADIATIONAL COOLING. WHILE WE ENDED
THE GROWING SEASON WITH LAST NIGHTS FREEZE...TEMPERATURES WILL
ONCE AGAIN FALL BELOW FREEZING ACROSS MOST OF THE REGION.
TEMPERATURES WERE TWEAKED FROM LAST NIGHTS VALUES AND BIAS
CORRECTED MOS.
WARM ADVECTION AND SUNSHINE WILL PROVIDE FOR WARMING TEMPERATURES
TOMORROW...ALTHOUGH HIGHS WERE FORECAST 5-10 DEGREES BELOW
SEASONAL AVERAGES.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
MUCH OF THE FIRST HALF OF THE WEEK WILL BE DOMINATED BY GENERALLY
ZONAL FLOW ALOFT...A PROGRESSIVE FLOW PATTERN THAT WILL SUPPORT
THE RAPID ERADICATION OF THE SURFACE HIGH PRESSURE RESPONSIBLE FOR
THE COLD WEEKEND. A WARM FRONT WILL SHARPEN ACROSS THE GREAT LAKES
TUESDAY NIGHT INTO WEDNESDAY...LEAVING THE FORECAST AREA SOLIDLY
IN THE WARM SECTOR AND H9 TRAJECTORIES TRANSPORTING MODIFIED GULF
AIR INTO THE REGION.
THROUGH WEDNESDAY NIGHT...IT APPEARS THE ACTIVE JET WILL REMAIN
IN SOUTHERN CANADA...SO ANY PRECIPITATION CHANCES APPEAR QUITE
LIMITED OWING TO MEAGER MOISTURE AND PROGRESSIVE...LOW-AMPLITUDE
WAVES IN THE FLOW. THESE CHANCES ARE HIGHEST ALONG THE SHARPENING
WARM FRONT...WHICH SHOULD REMAIN NORTH OF THE FORECAST AREA. POPS
WERE TRENDED DOWNWARD MODESTLY IN THE EARLIER PERIODS AND FOCUSED
PRIMARILY ACROSS THE FAR-NORTHERN ZONES... WITH INCREASING CHANCES
WEDNESDAY NIGHT AREA-WIDE AS A SHORTWAVE TROUGH AXIS IMPINGES ON
THE REGION.
TEMPERATURES WILL INCREASE AGGRESSIVELY THROUGH THE WEEK AS H9
WARM ADVECTION ENSUES ON A 30-40KT LOW-LEVEL JET. MAXIMA COULD
APPROACH 70 IN SOME SPOTS BY MID-WEEK AHEAD OF A COLD FRONTAL
PASSAGE LATE IN THE WEEK. MINIMA ALSO WILL BE ABOVE NORMAL IN THE
MID-UPPER 40S AS CLOUD COVER AND MOISTURE ADVECTION RETARD
OVERNIGHT RADIATIONAL COOLING. KRAMAR
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
DIGGING LOW PRESSURE IN THE LEE OF THE CANADIAN ROCKIES QUICKLY
MOVES INTO THE WESTERN GREAT LAKES BY LATE WEDNESDAY. A TRAILING
COLD FRONT WILL CROSS THE FORECAST AREA THURSDAY...BUT LIMITED
MOISTURE AND PROGRESSIVE NATURE OF THE SYSTEM ARE EXPECTED TO KEEP
PRECIPITATION LIMITED. KEPT POPS IN LOW CHANCE RANGE.
THE LASTING IMPACT OF THIS SYSTEM WILL MANIFEST AS AN
AMPLIFICATION OF THE LARGE SCALE UPPER-LEVEL FLOW. AS THE LOW
CONTINUES TO DIG OVER THE NORTHEASTERN CONUS...AN EXPANSIVE RIDGE
WILL SET UP OVER THE MISSISSIPPI VALLEY BY FRIDAY. THIS UPPER HIGH
WILL QUELL ANY POTENTIAL PRECIPITATION THROUGH THE EARLY PART OF
THE WEEKEND...AND AS THE AXIS SLOWLY SHIFTS EAST...TEMPERATURES
WILL CONTINUE TO INCREASE.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
CLOUD COVERAGE WILL GRADUALLY CLEAR OUT OVERNIGHT WITH
NORTHWESTERLY WINDS BECOMING LIGHT AS HIGH PRESSURE BECOMES THE
DOMINANT FEATURE ACROSS THE REGION. NO FLIGHT RESTRICTIONS ARE
ANTICIPATED THROUGH THE TAF PERIOD.
OUTLOOK...MONDAY THROUGH THURSDAY.
GENERAL VFR UNDER HIGH PRESSURE.
&&
.CLIMATE...
A WIDESPREAD FREEZE OCCURRED OVERNIGHT IN ALL ZONES...RESULTING IN A
CANCELLATION OF THE FROST/FREEZE PROGRAM FOR THE AUTUMN SEASON.
REFER TO PNSPBZ FOR DETAILS.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
349 PM EDT SUN OCT 18 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 523 AM EDT SUN OCT 18 2015
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A FAIRLY DEEP TROF OVER
ERN N AMERICA AND A RIDGE TO THE W WITH AXIS OVER THE HIGH PLAINS.
BTWN THESE FEATURES...NW FLOW CONTINUES OVER THE UPPER GREAT LAKES
EARLY THIS MORNING...BUT HEIGHTS ARE RISING AS THE RIDGE AND TROF
ARE SHIFTING E. LES CONTINUES INTO THE ERN FCST AREA...E OF
MARQUETTE. LES WAS MDT TO HVY AT TIMES IN ALGER AND NRN SCHOOLCRAFT
COUNTIES FOR SEVERAL HRS DURING THE NIGHT...BUT LES IS NOW SHOWING A
NOTABLE DIMINISHING TREND UNDER FALLING SUBSIDENCE INVERSION. WITH
THE START OF WAA...LAKE EFFECT CLOUDS OFF WRN LAKE SUPERIOR ARE
DECREASING.
SFC HIGH PRES RIDGE AXIS NOW JUST W OF LAKE SUPERIOR IS FCST TO
SHIFT QUICKLY E ACROSS THE FCST AREA TODAY. ALONG WITH THE FALLING
SUBSIDENCE INVERSION...LES INTO THE ERN FCST WILL END THIS MORNING.
ONLY MINOR ADDITIONAL SNOW ACCUMULATIONS UNDER AN INCH WILL OCCUR
EARLY THIS MORNING. IF THERE ARE ANY LINGERING CLOUDS OVER THE W
AFTER SUNRISE...THEY WILL QUICKLY CLEAR OUT THIS MORNING. SKIES WILL
ALSO BECOME MOSTLY SUNNY E THIS AFTN. HIGHS TODAY WILL TOP OUT IN
THE 40S E TO AS HIGH AS THE LOWER 50S W WHERE WAA AND MORE SUN WILL
AID WARMING. PRES GRADIENT WILL QUICKLY TIGHTEN AFTER PASSAGE OF THE
HIGH PRES RIDGE AXIS AS A RAPIDLY DEEPENING SFC LOW TRACKING E TO
HUDSON BAY PUSHES AN ASSOCIATED TROF INTO THE WRN PLAINS. EXPECT S
WINDS TO ALREADY BEGIN TO SHOW SOME GUSTINESS DURING THE LATTER
PORTION OF THE AFTN OVER THE W HALF.
WINDS WILL THEN BE THE MAIN STORY TONIGHT. A DEEP SFC LOW OVER
HUDSON BAY...DROPPING TO A PRES OF AROUND 28.7 INCHES...WILL DRIVE
ASSOCIATED SFC TROF INTO MN. A 50+KT LOW-LEVEL JET WILL SHIFT INTO
UPPER MI DURING THE NIGHT. WHILE WAA AND NOCTURNAL COOLING WILL
RESULT IN CONSIDERABLE STABILITY PREVENTING ACCESS TO THE PEAK LOW-
LEVEL WINDS...MAX PRES FALLS OF AROUND 6MB/3HR SHIFTING ACROSS NRN
ONTARIO WILL AID AN INCREASE IN SFC WINDS/GUSTINESS...MAINLY IN THE
HIGH TERRAIN AND ESPECIALLY IN THE DOWNSLOPE AREAS NEAR LAKE
SUPERIOR AND ALONG NRN LAKE MI E OF ESCANABA. COULD BECOME FAIRLY
WINDY AT LEAST FOR A FEW HRS DURING THE TIME THAT THE ISALLOBARIC
WIND COMPONENT IS MAXIMIZED. WINDS WILL KEEP MIN TEMPS UP IN THE 30S
TO LWR 40S TONIGHT. INTERIOR SHELTERED LOCATIONS IN THE CNTRL AND E
MAY FALL TO THE LWR 30S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 349 PM EDT SUN OCT 18 2015
HI PRES BLDG THRU ONTARIO WL BRING A PERIOD OF DRY...SEASONABLE WX
ON TUE BEFORE A PAIR OF DISTURBANCES BRING THE CHC FOR SOME RAIN
LATE TUE NIGHT INTO WED NGT. THERE WL BE GENERALLY DRY WX ON THU
INTO FRI BEFORE AN APPROACHING COLD FRONT CAUSES MORE SHOWERS NEXT
FRI/SAT. THE SW FLOW AHEAD OF THIS FRONT WILL BRING THE WARMEST WX
RELATIVE TO NORMAL IN THE EXTENDED PERIOD ON FRI.
MON NGT/TUE...SFC COLD FNT ASSOCIATED WITH VIGOROUS SHRTWV/DEEP SFC
LO PRES CROSSING HUDSON BAY IS FCST TO PASS THRU UPR MI ON MON EVNG
AHEAD OF SFC HI PRES IN CENTRAL CANADA BLDG TOWARD NW ONTARIO. SINCE
THE FLOW ALF OVER THE FNT IS FCST TO BE WNW...DRYING ALF WL PRECEDE
THE SFC FROPA...SO ANY LINGERING CLDS OVER THE SE CWA WL EXIT EARLY
IN THE EVNG AND GIVE WAY TO A PERIOD OF MOCLR CONDITIONS. BUT AS THE
SFC HI PRES MOVES INTO FAR NW ONTARIO LATE MON NGT AND THEN E THRU
TUE TO THE N OF STALLED FNT IN THE LOWER LKS...A SHALLOW BUT INCRSG
NNE VEERING E FLOW ON ITS SRN FLANK AND OFF LK SUP IS LIKELY TO
GENERATE SOME LO CLDS AT LEAST IN THE UPSLOPE HIER TERRAIN AREAS NEAR
LK SUP BLO SHARP SUBSIDENCE INVRN NEAR 3K FT SHOWN ON FCST SDNGS.
THERE WL ALSO BE SOME HI CLDS AROUND ON TUE TO THE NE OF A DVLPG LO
PRES IN THE NCENTRAL PLAINS. WITH THE INFUSION OF SHALLOW CNDN AIR...
TUE WL BE COOLER THAN MON...ESPECIALLY OVER THE NCENTRAL IF THERE IS
EXTENSIVE SC. TEMPS ARE LIKELY TO HOLD IN THE 40S OVER MUCH OF THIS
AREA.
TUE NGT THRU WED NGT...THERE REMAINS SOME UNCERTAINTY ON THE
INTERACTION BTWN A SHRTWV MOVING E THRU THE ZONAL NRN BRANCH
FLOW NEAR THE CNDN BORDER AND ANOTHER WEAKER DISTURBANCE PASSING THRU
THE WEAKER SRN BRANCH FLOW OVER THE CONUS THAT WL BE RESPONSIBLE FOR
THE SFC LO TAKING SHAPE IN THE NCENTRAL PLAINS. ALTHOUGH ALL THE
MODELS INDICATE THE NRN BRANCH DISTURBANCE WL BE STRONGER...THE SRN
BRANCH SHRTWV/SFC LO WL BE IN CLOSER PROXIMITY TO SOME HIER PWAT/THE
STNRY FNT TO THE S AND THUS MAY HAVE A SGNFT IMPACT ON POPS. THE
MODELS IN GENERAL SHOW TWO AREAS OF HIER QPF FOLLOWING THE GREATER
DYNAMIC SUPPORT ASSOCIATED WITH THESE OUT-OF-PHASE DISTURBANCES. MOST
OF THE SCENARIOS SHOW UPR MI REMAINING BTWN THE TWO QPF MAXIMUMS
BEFORE MORE PHASING AND THE SEPARATE PCPN AREAS TEND TO MERGE TO THE
E OF THE CWA LATER ON WED. AT THIS POINT...WL FOLLOW MODEL CONSENSUS
THAT FEATURES CHC POPS AHEAD OF THE SRN SHRTWV/SLOWLY RETURNING WARM
FNT ARRIVING FM THE SW ON TUE NGT AND THEN DIMINISHING ON WED NGT
FOLLOWING THE PASSAGE OF THE SHRTWVS TO THE E AND APRCH OF TRAILING
HI PRES FM THE W. RIGHT NOW...MOST OF THE MODELS INDICATE THE INCRSG
NW FLOW BEHIND THE STRENGTHENING/DEPARTING WL NOT DRAG ENUF COLD AIR
/FCST H85 TEMPS ARND -2C/ INTO THE UPR LKS TO GENERATE ANY SGNFT LK
EFFECT PCPN ON WED NGT. THE 18/00Z EMCWF IS AN EXCEPTION...WITH A
SHARPER CYC NNW FLOW AND H85 TEMPS FALLING CLOSER TO -5C BY 12Z THU.
SUSPECT THERE WL BE ENUF COOLING TO RESULT IN AT LEAST SOME LO CLDS
OVER MAINLY THE NRN TIER ON WED NGT INTO EARLY THU IN THE LLVL NNW
FLOW BEHIND THE DEPARTING LO.
EXTENDED...ANY LK CLDS OVER THE NRN TIER ON THU MRNG WL GIVE WAY TO
MORE SUNSHINE IN THE AFTN WITH THE ARRIVAL OF AN UPR RDG/SFC HI PRES
TRAILING THE DEPARTING LO PRES. DRY...QUIET AND SEASONABLY CHILLY
CONDITIONS WL THEN PREVAIL THU NGT AS THE RDG PASSES OVHD. ALTHOUGH
FRI WL START OFF DRY...MORE CLDS AND PERHAPS SOME SHOWERS WL MOVE
INTO AT LEAST THE W HALF DURING THE AFTN. MOST OF THE LONGER RANGE
GUIDANCE INDICATES A COLD FNT/BAND OF SHOWERS ASSOCIATED WITH A
SHRTWV RIDING NE OUT OF THE WRN TROF WL CROSS UPR MI SOMETIME BTWN
FRI NGT AND SAT NGT AHEAD OF TRAILING HI PRES APRCHG LATER IN THE
WEEKEND. ABOVE NORMAL TEMPS ON FRI INTO SAT WL GIVE WAY TO MORE
SEASONABLE WX ON SUN FOLLOWING THE FROPA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 100 PM EDT SUN OCT 18 2015
HIGH PRESSURE CENTERED OVER S IL/SIN/KY IS EXTENDING A RIDGE OVER
EUPPER MI IS KEEPING DRY WEATHER GOING OVER THE 3 TAF SITES
TODAY.HOWEVER...THERE IS A CHANGE IN THE FORM OF AN INCREASED
PRESSUREGRADIENT THIS AFTERNOON AS RAPIDLY DEEPENING LOW PRESSURE
ALONG THEN MANITOBA BORDER SHIFTS ACROSS HUDSON BAY TONIGHT THROUGH
MONDAY.WHILE VFR CONDITIONS REMAIN...WINDS WILL BE THE MAIN ISSUE
THISPERIOD. LLWS IS EXPECTED TONIGHT AT CMX AND SAW AS A STRONG
LLJDEVELOPS OVER THE NOCTURNAL INVERSION. DID NOT INCLUDE LLWS
ATIWD...DUE TO THE WINDS REMAINING MORE GUSTY AND MIXED OVERNIGHT.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 PM EDT SUN OCT 18 2015
TIGHTENING PRES GRADIENT BEHIND HI PRES SHIFTING INTO THE NE CONUS
AND DEEP LO PRES OVER HUDSON BAY/ATTENDANT COLD FRONT EXTENDING
INTO THE UPPER MS RIVER VALLEY WILL CAUSE SW GALES TONIGHT INTO MON
MORNING...ESPECIALLY BETWEEN ISLE ROYALE AND THE KEWEENAW AND OVER
THE EASTERN PART OF THE LAKE WHERE THIS TYPE OF PATTERN TYPICALLY
PRODUCES THE STRONGEST WINDS. THE HIGHEST OBS PLATFORMS WILL PROBABLY
SEE WIND GUSTS IN EXCESS OF 40KT FOR A TIME. MAINTAINED GOING
GALE WARNINGS ISSUED EARLIER FOR THESE AREAS. WINDS WILL DIMINISH TO
UNDER 25KT W TO E ON MON. AFTER A COLD FRONT PASSES LATE MON
AFTERNOON AND EVENING...N TO NE WINDS WILL INCREASE TO 20-30KT OVER
MUCH OF THE LAKE AHEAD OF HIGH PRES THAT WILL BUILD SE INTO NORTHERN
ONTARIO ON TUE. PLAN ON THE STRONGEST WINDS OVER WESTERN LAKE
SUPERIOR WHERE THE TERRAIN WILL FUNNEL AND ENHANCE THIS FLOW. WINDS
WILL THEN VEER TO THE E-SE TUE NIGHT/WED AS THE HI MOVES INTO QUEBEC
AND A LO PRES TROF APPROACHES. THE STRONGER SE WINDS UP TO 30 KTS
ARE MOST LIKELY OVER THE E HALF OF THE LAKE ON WED. AFTER THE TROF
PASSES BY LATE WED...WINDS WILL SHIFT TO THE NW AND DIMINISH BY LATE
THU AS TRAILING HI PRES BUILDS INTO THE WESTERN GREAT LAKES. S WINDS
WILL INCREASE UP TO 25 KTS ON FRI FOLLOWING THE PASSAGE OF THIS HI TO
THE E AND UNDER A SHARPENING PRES GRADIENT AHEAD OF AN APPROACHING
COLD FRONT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 11 PM THIS EVENING TO 11 AM EDT MONDAY FOR
LSZ266-267.
GALE WARNING FROM 11 PM THIS EVENING TO 8 AM EDT MONDAY FOR
LSZ263-264.
LAKE MICHIGAN...
GALE WARNING FROM 1 AM TO 2 PM EDT MONDAY FOR LMZ221-248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KC
AVIATION...KF
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
100 PM EDT SUN OCT 18 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 523 AM EDT SUN OCT 18 2015
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A FAIRLY DEEP TROF OVER
ERN N AMERICA AND A RIDGE TO THE W WITH AXIS OVER THE HIGH PLAINS.
BTWN THESE FEATURES...NW FLOW CONTINUES OVER THE UPPER GREAT LAKES
EARLY THIS MORNING...BUT HEIGHTS ARE RISING AS THE RIDGE AND TROF
ARE SHIFTING E. LES CONTINUES INTO THE ERN FCST AREA...E OF
MARQUETTE. LES WAS MDT TO HVY AT TIMES IN ALGER AND NRN SCHOOLCRAFT
COUNTIES FOR SEVERAL HRS DURING THE NIGHT...BUT LES IS NOW SHOWING A
NOTABLE DIMINISHING TREND UNDER FALLING SUBSIDENCE INVERSION. WITH
THE START OF WAA...LAKE EFFECT CLOUDS OFF WRN LAKE SUPERIOR ARE
DECREASING.
SFC HIGH PRES RIDGE AXIS NOW JUST W OF LAKE SUPERIOR IS FCST TO
SHIFT QUICKLY E ACROSS THE FCST AREA TODAY. ALONG WITH THE FALLING
SUBSIDENCE INVERSION...LES INTO THE ERN FCST WILL END THIS MORNING.
ONLY MINOR ADDITIONAL SNOW ACCUMULATIONS UNDER AN INCH WILL OCCUR
EARLY THIS MORNING. IF THERE ARE ANY LINGERING CLOUDS OVER THE W
AFTER SUNRISE...THEY WILL QUICKLY CLEAR OUT THIS MORNING. SKIES WILL
ALSO BECOME MOSTLY SUNNY E THIS AFTN. HIGHS TODAY WILL TOP OUT IN
THE 40S E TO AS HIGH AS THE LOWER 50S W WHERE WAA AND MORE SUN WILL
AID WARMING. PRES GRADIENT WILL QUICKLY TIGHTEN AFTER PASSAGE OF THE
HIGH PRES RIDGE AXIS AS A RAPIDLY DEEPENING SFC LOW TRACKING E TO
HUDSON BAY PUSHES AN ASSOCIATED TROF INTO THE WRN PLAINS. EXPECT S
WINDS TO ALREADY BEGIN TO SHOW SOME GUSTINESS DURING THE LATTER
PORTION OF THE AFTN OVER THE W HALF.
WINDS WILL THEN BE THE MAIN STORY TONIGHT. A DEEP SFC LOW OVER
HUDSON BAY...DROPPING TO A PRES OF AROUND 28.7 INCHES...WILL DRIVE
ASSOCIATED SFC TROF INTO MN. A 50+KT LOW-LEVEL JET WILL SHIFT INTO
UPPER MI DURING THE NIGHT. WHILE WAA AND NOCTURNAL COOLING WILL
RESULT IN CONSIDERABLE STABILITY PREVENTING ACCESS TO THE PEAK LOW-
LEVEL WINDS...MAX PRES FALLS OF AROUND 6MB/3HR SHIFTING ACROSS NRN
ONTARIO WILL AID AN INCREASE IN SFC WINDS/GUSTINESS...MAINLY IN THE
HIGH TERRAIN AND ESPECIALLY IN THE DOWNSLOPE AREAS NEAR LAKE
SUPERIOR AND ALONG NRN LAKE MI E OF ESCANABA. COULD BECOME FAIRLY
WINDY AT LEAST FOR A FEW HRS DURING THE TIME THAT THE ISALLOBARIC
WIND COMPONENT IS MAXIMIZED. WINDS WILL KEEP MIN TEMPS UP IN THE 30S
TO LWR 40S TONIGHT. INTERIOR SHELTERED LOCATIONS IN THE CNTRL AND E
MAY FALL TO THE LWR 30S.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 443 AM EDT SUN OCT 18 2015
TEMPERATURES THROUGH THE EXTENDED WILL BE NEAR TO SLIGHTLY ABOVE
NORMAL WITH A COUPLE CHANCES FOR RAINFALL.
MONDAY THROUGH TUESDAY...THE BROAD SURFACE RIDGE OVER THE MID
ATLANTIC STATES MONDAY WILL CONTINUE TO SLIDE TO THE SOUTHEAST. AS
THIS HAPPENS...A FAIRLY STRONG LOW PRESSURE SYSTEM OVER HUDSON BAY
WILL SLIDE INTO NORTHWEST QUEBEC. THERE WILL BE A FAIRLY STRONG
PRESSURE GRADIENT BETWEEN THE TWO SYSTEMS ALONG WITH A 40 TO 50 KNOT
LLJ...MAINLY OVER EASTERN LAKE SUPERIOR AND NORTHERN LAKE MICHIGAN
MONDAY MORNING BEFORE THE GRADIENT SLOWLY RELAXES DURING THE
AFTERNOON HOURS. THIS ALONG WITH DECENT MIXING IN THE LOWER LEVEL
WILL ALLOW FOR GUSTY SOUTHWEST WINDS...INCLUDING GALES ON LAKE
SUPERIOR AND LAKE MICHIGAN. ADDITIONALLY...THE LOW PRESSURE SYSTEM
HAS A WEAK TRAILING COLD FRONT STRETCHING FROM HUDSON BAY TO NEAR
THE ARROWHEAD OF MINNESOTA MONDAY MORNING. THIS FRONT WILL BECOME
MORE ENE TO WSW ORIENTED ACROSS THE AREA BEFORE QUICKLY SLIDING TO
THE SOUTH AND EAST OF THE AREA MONDAY NIGHT. THERE MAY BE A FEW RAIN
SHOWERS ALONG THE COLD FRONT BUT MOISTURE LOOKS TO BE FAIRLY LIMITED
AT THIS POINT AND FORCING LOOKS TO BE FAIRLY WEAK. HAVE ONLY KEPT
ISOLATED RAIN SHOWERS IN THE FORECAST FOR MONDAY. BEHIND THE COLD
FRONT...A SURFACE RIDGE...ZONAL TO SLIGHT UPPER LEVEL 500MB RIDGING
AND DRY AIR WILL BUILD INTO THE AREA LATE MONDAY NIGHT AND LINGER
THROUGH MUCH OF THE DAY TUESDAY BRINGING WARMER TEMPERATURES AND AN
END TO ANY ISOLATED SHOWERS THAT MAY DEVELOP MONDAY.
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...AS THE AFOREMENTIONED HIGH
PRESSURE SYSTEM SLIDES TO THE EAST OF THE AREA...A FAIRLY STRONG
SHORTWAVE AND SURFACE LOW DEVELOPING OVER SOUTHERN CANADA...WILL
BEGIN TO SLIDE EASTWARD TOWARD THE AREA TUESDAY NIGHT. IT LOOKS LIKE
THERE WILL BE ANOTHER...WEAKER...SHORTWAVE THAT SLIDES IN AHEAD OF
THE MAIN SHORTWAVE WHICH COULD HELP TO KICK UP SCATTERED RAIN
SHOWERS TUESDAY NIGHT...HOWEVER...THE BETTER FORCING WILL BE WITH
THE MUCH STRONGER SHORTWAVE PROGGED TO SLIDE ACROSS LAKE SUPERIOR
AND MUCH OF THE U.P. WEDNESDAY INTO WEDNESDAY NIGHT.
THURSDAY THROUGH THE EXTENDED...CONTINUED TO USE A CONSENSUS OF THE
MODELS THROUGH THIS TIME PERIOD. THE GENERAL TREND IS FOR A SURFACE
RIDGE AND ASSOCIATED UPPER LEVEL RIDGE TO BUILD INTO THE AREA
THURSDAY AND LINGER THROUGH THURSDAY NIGHT. THERE ARE SOME MODEL
DISAGREEMENTS BEYOND THAT. FRIDAY THE NEXT LOW PRESSURE
SYSTEM...DEVELOPING OVER THE PLAINS IS PROGGED TO PROGRESS SLOWLY
TOWARD THE EAST. THE GFS...AS IS TYPICAL FOR THIS TIME OF
YEAR...RUSHES THE LOW PRESSURE SYSTEM AND ASSOCIATED COLD FRONT
EASTWARD. THIS SOLUTION WOULD BRING PRECIPITATION INTO THE U.P.
FRIDAY AND RUSH IT OUT OF THE AREA BY SATURDAY MORNING. THE EC...IS
LESS PROGRESSIVE WITH THIS SYSTEM...WHICH KEEP THE HIGH PRESSURE IN
PLACE A BIT LONGER...KEEPING CONDITIONS DRY THROUGH FRIDAY
AFTERNOON. THE RAIN SHOWERS WITH THE EC SOLUTION WOULD THEN LINGER
THROUGH SATURDAY. THE REDUCED CONFIDENCE IN ANY ONE PARTICULAR MODEL
HAS LEANED THE FORECAST MORE TOWARD THE CONSENSUS OF THE MODELS
WHICH KEEPS CHANCE POPS IN THE FORECAST FRIDAY THROUGH SATURDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 100 PM EDT SUN OCT 18 2015
HIGH PRESSURE CENTERED OVER S IL/SIN/KY IS EXTENDING A RIDGE OVER
EUPPER MI IS KEEPING DRY WEATHER GOING OVER THE 3 TAF SITES
TODAY.HOWEVER...THERE IS A CHANGE IN THE FORM OF AN INCREASED
PRESSUREGRADIENT THIS AFTERNOON AS RAPIDLY DEEPENING LOW PRESSURE
ALONG THEN MANITOBA BORDER SHIFTS ACROSS HUDSON BAY TONIGHT THROUGH
MONDAY.WHILE VFR CONDITIONS REMAIN...WINDS WILL BE THE MAIN ISSUE
THISPERIOD. LLWS IS EXPECTED TONIGHT AT CMX AND SAW AS A STRONG
LLJDEVELOPS OVER THE NOCTURNAL INVERSION. DID NOT INCLUDE LLWS
ATIWD...DUE TO THE WINDS REMAINING MORE GUSTY AND MIXED OVERNIGHT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 523 AM EDT SUN OCT 18 2015
HIGH PRES RIDGE WILL QUICKLY SHIFT ACROSS LAKE SUPERIOR TODAY...
RESULTING IN A BRIEF PERIOD OF LIGHT WINDS. ALREADY IN THE AFTN...
TIGHTENING PRES GRADIENT BEHIND THE RIDGE WILL LEAD TO INCREASING S
WINDS...GUSTING TO 20-25KT BY LATE AFTN. WINDS INCREASE FURTHER
TONIGHT AS A DEEP LOW TRACKS E OVER HUDSON BAY. WITH AN AREA OF MAX
PRES FALLS PASSING N OF THE LAKE...S TO SW WINDS WILL LIKELY REACH
GALE FORCE...ESPECIALLY BETWEEN ISLE ROYALE AND THE KEWEENAW...AND
OVER THE EASTERN PART OF THE LAKE WHERE THIS TYPE OF PATTERN
TYPICALLY PRODUCES THE STRONGEST WINDS. THE HIGHEST OBS PLATFORMS
WILL PROBABLY SEE WIND GUSTS IN EXCESS OF 40KT FOR A TIME.
WINDS WILL DIMINISH TO UNDER 25KT W TO E ON MON. AFTER A TROF PASSES
LATE MON AFTN AND EVENING...N TO NE WINDS WILL INCREASE TO 20-30KT
OVER MUCH OF THE LAKE AHEAD OF HIGH PRES THAT WILL BUILD SE INTO NRN
ONTARIO TUE. WINDS WILL THEN VEER TO THE E-SE TUE NIGHT/WED AS THE
HIGH MOVES INTO QUEBEC AND A LOW PRES TROF APPROACHES. AFTER THE
TROF PASSES...WINDS WILL FINALLY DIMINISH LATER THU WHEN HIGH PRES
BUILDS INTO THE UPPER GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 11 PM THIS EVENING TO 11 AM EDT MONDAY FOR
LSZ266-267.
GALE WARNING FROM 11 PM THIS EVENING TO 8 AM EDT MONDAY FOR
LSZ263-264.
LAKE MICHIGAN...
GALE WARNING FROM 1 AM TO 2 PM EDT MONDAY FOR LMZ221-248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KEC
AVIATION...KF
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
744 AM EDT SUN OCT 18 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 523 AM EDT SUN OCT 18 2015
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A FAIRLY DEEP TROF OVER
ERN N AMERICA AND A RIDGE TO THE W WITH AXIS OVER THE HIGH PLAINS.
BTWN THESE FEATURES...NW FLOW CONTINUES OVER THE UPPER GREAT LAKES
EARLY THIS MORNING...BUT HEIGHTS ARE RISING AS THE RIDGE AND TROF
ARE SHIFTING E. LES CONTINUES INTO THE ERN FCST AREA...E OF
MARQUETTE. LES WAS MDT TO HVY AT TIMES IN ALGER AND NRN SCHOOLCRAFT
COUNTIES FOR SEVERAL HRS DURING THE NIGHT...BUT LES IS NOW SHOWING A
NOTABLE DIMINISHING TREND UNDER FALLING SUBSIDENCE INVERSION. WITH
THE START OF WAA...LAKE EFFECT CLOUDS OFF WRN LAKE SUPERIOR ARE
DECREASING.
SFC HIGH PRES RIDGE AXIS NOW JUST W OF LAKE SUPERIOR IS FCST TO
SHIFT QUICKLY E ACROSS THE FCST AREA TODAY. ALONG WITH THE FALLING
SUBSIDENCE INVERSION...LES INTO THE ERN FCST WILL END THIS MORNING.
ONLY MINOR ADDITIONAL SNOW ACCUMULATIONS UNDER AN INCH WILL OCCUR
EARLY THIS MORNING. IF THERE ARE ANY LINGERING CLOUDS OVER THE W
AFTER SUNRISE...THEY WILL QUICKLY CLEAR OUT THIS MORNING. SKIES WILL
ALSO BECOME MOSTLY SUNNY E THIS AFTN. HIGHS TODAY WILL TOP OUT IN
THE 40S E TO AS HIGH AS THE LOWER 50S W WHERE WAA AND MORE SUN WILL
AID WARMING. PRES GRADIENT WILL QUICKLY TIGHTEN AFTER PASSAGE OF THE
HIGH PRES RIDGE AXIS AS A RAPIDLY DEEPENING SFC LOW TRACKING E TO
HUDSON BAY PUSHES AN ASSOCIATED TROF INTO THE WRN PLAINS. EXPECT S
WINDS TO ALREADY BEGIN TO SHOW SOME GUSTINESS DURING THE LATTER
PORTION OF THE AFTN OVER THE W HALF.
WINDS WILL THEN BE THE MAIN STORY TONIGHT. A DEEP SFC LOW OVER
HUDSON BAY...DROPPING TO A PRES OF AROUND 28.7 INCHES...WILL DRIVE
ASSOCIATED SFC TROF INTO MN. A 50+KT LOW-LEVEL JET WILL SHIFT INTO
UPPER MI DURING THE NIGHT. WHILE WAA AND NOCTURNAL COOLING WILL
RESULT IN CONSIDERABLE STABILITY PREVENTING ACCESS TO THE PEAK LOW-
LEVEL WINDS...MAX PRES FALLS OF AROUND 6MB/3HR SHIFTING ACROSS NRN
ONTARIO WILL AID AN INCREASE IN SFC WINDS/GUSTINESS...MAINLY IN THE
HIGH TERRAIN AND ESPECIALLY IN THE DOWNSLOPE AREAS NEAR LAKE
SUPERIOR AND ALONG NRN LAKE MI E OF ESCANABA. COULD BECOME FAIRLY
WINDY AT LEAST FOR A FEW HRS DURING THE TIME THAT THE ISALLOBARIC
WIND COMPONENT IS MAXIMIZED. WINDS WILL KEEP MIN TEMPS UP IN THE 30S
TO LWR 40S TONIGHT. INTERIOR SHELTERED LOCATIONS IN THE CNTRL AND E
MAY FALL TO THE LWR 30S.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 443 AM EDT SUN OCT 18 2015
TEMPERATURES THROUGH THE EXTENDED WILL BE NEAR TO SLIGHTLY ABOVE
NORMAL WITH A COUPLE CHANCES FOR RAINFALL.
MONDAY THROUGH TUESDAY...THE BROAD SURFACE RIDGE OVER THE MID
ATLANTIC STATES MONDAY WILL CONTINUE TO SLIDE TO THE SOUTHEAST. AS
THIS HAPPENS...A FAIRLY STRONG LOW PRESSURE SYSTEM OVER HUDSON BAY
WILL SLIDE INTO NORTHWEST QUEBEC. THERE WILL BE A FAIRLY STRONG
PRESSURE GRADIENT BETWEEN THE TWO SYSTEMS ALONG WITH A 40 TO 50 KNOT
LLJ...MAINLY OVER EASTERN LAKE SUPERIOR AND NORTHERN LAKE MICHIGAN
MONDAY MORNING BEFORE THE GRADIENT SLOWLY RELAXES DURING THE
AFTERNOON HOURS. THIS ALONG WITH DECENT MIXING IN THE LOWER LEVEL
WILL ALLOW FOR GUSTY SOUTHWEST WINDS...INCLUDING GALES ON LAKE
SUPERIOR AND LAKE MICHIGAN. ADDITIONALLY...THE LOW PRESSURE SYSTEM
HAS A WEAK TRAILING COLD FRONT STRETCHING FROM HUDSON BAY TO NEAR
THE ARROWHEAD OF MINNESOTA MONDAY MORNING. THIS FRONT WILL BECOME
MORE ENE TO WSW ORIENTED ACROSS THE AREA BEFORE QUICKLY SLIDING TO
THE SOUTH AND EAST OF THE AREA MONDAY NIGHT. THERE MAY BE A FEW RAIN
SHOWERS ALONG THE COLD FRONT BUT MOISTURE LOOKS TO BE FAIRLY LIMITED
AT THIS POINT AND FORCING LOOKS TO BE FAIRLY WEAK. HAVE ONLY KEPT
ISOLATED RAIN SHOWERS IN THE FORECAST FOR MONDAY. BEHIND THE COLD
FRONT...A SURFACE RIDGE...ZONAL TO SLIGHT UPPER LEVEL 500MB RIDGING
AND DRY AIR WILL BUILD INTO THE AREA LATE MONDAY NIGHT AND LINGER
THROUGH MUCH OF THE DAY TUESDAY BRINGING WARMER TEMPERATURES AND AN
END TO ANY ISOLATED SHOWERS THAT MAY DEVELOP MONDAY.
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...AS THE AFOREMENTIONED HIGH
PRESSURE SYSTEM SLIDES TO THE EAST OF THE AREA...A FAIRLY STRONG
SHORTWAVE AND SURFACE LOW DEVELOPING OVER SOUTHERN CANADA...WILL
BEGIN TO SLIDE EASTWARD TOWARD THE AREA TUESDAY NIGHT. IT LOOKS LIKE
THERE WILL BE ANOTHER...WEAKER...SHORTWAVE THAT SLIDES IN AHEAD OF
THE MAIN SHORTWAVE WHICH COULD HELP TO KICK UP SCATTERED RAIN
SHOWERS TUESDAY NIGHT...HOWEVER...THE BETTER FORCING WILL BE WITH
THE MUCH STRONGER SHORTWAVE PROGGED TO SLIDE ACROSS LAKE SUPERIOR
AND MUCH OF THE U.P. WEDNESDAY INTO WEDNESDAY NIGHT.
THURSDAY THROUGH THE EXTENDED...CONTINUED TO USE A CONSENSUS OF THE
MODELS THROUGH THIS TIME PERIOD. THE GENERAL TREND IS FOR A SURFACE
RIDGE AND ASSOCIATED UPPER LEVEL RIDGE TO BUILD INTO THE AREA
THURSDAY AND LINGER THROUGH THURSDAY NIGHT. THERE ARE SOME MODEL
DISAGREEMENTS BEYOND THAT. FRIDAY THE NEXT LOW PRESSURE
SYSTEM...DEVELOPING OVER THE PLAINS IS PROGGED TO PROGRESS SLOWLY
TOWARD THE EAST. THE GFS...AS IS TYPICAL FOR THIS TIME OF
YEAR...RUSHES THE LOW PRESSURE SYSTEM AND ASSOCIATED COLD FRONT
EASTWARD. THIS SOLUTION WOULD BRING PRECIPITATION INTO THE U.P.
FRIDAY AND RUSH IT OUT OF THE AREA BY SATURDAY MORNING. THE EC...IS
LESS PROGRESSIVE WITH THIS SYSTEM...WHICH KEEP THE HIGH PRESSURE IN
PLACE A BIT LONGER...KEEPING CONDITIONS DRY THROUGH FRIDAY
AFTERNOON. THE RAIN SHOWERS WITH THE EC SOLUTION WOULD THEN LINGER
THROUGH SATURDAY. THE REDUCED CONFIDENCE IN ANY ONE PARTICULAR MODEL
HAS LEANED THE FORECAST MORE TOWARD THE CONSENSUS OF THE MODELS
WHICH KEEPS CHANCE POPS IN THE FORECAST FRIDAY THROUGH SATURDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 744 AM EDT SUN OCT 18 2015
VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW THRU THIS FCST PERIOD
AS THE LOW LEVEL AIR MASS BECOMES QUITE DRY. THERE WILL BE A PERIOD
OF BKN MID LEVEL CLOUDS AT KCMX/KSAW THIS MORNING INTO THE EARLY
AFTN. OTHERWISE...WITH SFC HIGH PRES RIDGE SHIFTING ACROSS THE
TERMINALS...WINDS WILL BE LIGHT THIS MORNING INTO EARLY AFTN. PRES
GRADIENT WILL THEN RAPIDLY TIGHTEN AS THE RIDGE SHIFTS E OF THE
TERMINALS...LEADING TO INCREASING SOUTHERLY WINDS WITH SOME
GUSTINESS AT KIWD/KSAW. LOW-LEVEL JET WILL DEVELOP OVERTOP NOCTURNAL
INVERSION TONIGHT...RESULTING IN LLWS AT KCMX/KSAW. WITH LOW-LEVEL
WINDS LIKELY REMAINING MORE MIXED/GUSTY AT KIWD...LLWS WAS NOT
INCLUDED AT THAT TERMINAL.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 523 AM EDT SUN OCT 18 2015
HIGH PRES RIDGE WILL QUICKLY SHIFT ACROSS LAKE SUPERIOR TODAY...
RESULTING IN A BRIEF PERIOD OF LIGHT WINDS. ALREADY IN THE AFTN...
TIGHTENING PRES GRADIENT BEHIND THE RIDGE WILL LEAD TO INCREASING S
WINDS...GUSTING TO 20-25KT BY LATE AFTN. WINDS INCREASE FURTHER
TONIGHT AS A DEEP LOW TRACKS E OVER HUDSON BAY. WITH AN AREA OF MAX
PRES FALLS PASSING N OF THE LAKE...S TO SW WINDS WILL LIKELY REACH
GALE FORCE...ESPECIALLY BETWEEN ISLE ROYALE AND THE KEWEENAW...AND
OVER THE EASTERN PART OF THE LAKE WHERE THIS TYPE OF PATTERN
TYPICALLY PRODUCES THE STRONGEST WINDS. THE HIGHEST OBS PLATFORMS
WILL PROBABLY SEE WIND GUSTS IN EXCESS OF 40KT FOR A TIME.
WINDS WILL DIMINISH TO UNDER 25KT W TO E ON MON. AFTER A TROF PASSES
LATE MON AFTN AND EVENING...N TO NE WINDS WILL INCREASE TO 20-30KT
OVER MUCH OF THE LAKE AHEAD OF HIGH PRES THAT WILL BUILD SE INTO NRN
ONTARIO TUE. WINDS WILL THEN VEER TO THE E-SE TUE NIGHT/WED AS THE
HIGH MOVES INTO QUEBEC AND A LOW PRES TROF APPROACHES. AFTER THE
TROF PASSES...WINDS WILL FINALLY DIMINISH LATER THU WHEN HIGH PRES
BUILDS INTO THE UPPER GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 11 PM THIS EVENING TO 11 AM EDT MONDAY FOR
LSZ266-267.
GALE WARNING FROM 11 PM THIS EVENING TO 8 AM EDT MONDAY FOR
LSZ263-264.
LAKE MICHIGAN...
GALE WARNING FROM 1 AM TO 2 PM EDT MONDAY FOR LMZ221-248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KEC
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
523 AM EDT SUN OCT 18 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 523 AM EDT SUN OCT 18 2015
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A FAIRLY DEEP TROF OVER
ERN N AMERICA AND A RIDGE TO THE W WITH AXIS OVER THE HIGH PLAINS.
BTWN THESE FEATURES...NW FLOW CONTINUES OVER THE UPPER GREAT LAKES
EARLY THIS MORNING...BUT HEIGHTS ARE RISING AS THE RIDGE AND TROF
ARE SHIFTING E. LES CONTINUES INTO THE ERN FCST AREA...E OF
MARQUETTE. LES WAS MDT TO HVY AT TIMES IN ALGER AND NRN SCHOOLCRAFT
COUNTIES FOR SEVERAL HRS DURING THE NIGHT...BUT LES IS NOW SHOWING A
NOTABLE DIMINISHING TREND UNDER FALLING SUBSIDENCE INVERSION. WITH
THE START OF WAA...LAKE EFFECT CLOUDS OFF WRN LAKE SUPERIOR ARE
DECREASING.
SFC HIGH PRES RIDGE AXIS NOW JUST W OF LAKE SUPERIOR IS FCST TO
SHIFT QUICKLY E ACROSS THE FCST AREA TODAY. ALONG WITH THE FALLING
SUBSIDENCE INVERSION...LES INTO THE ERN FCST WILL END THIS MORNING.
ONLY MINOR ADDITIONAL SNOW ACCUMULATIONS UNDER AN INCH WILL OCCUR
EARLY THIS MORNING. IF THERE ARE ANY LINGERING CLOUDS OVER THE W
AFTER SUNRISE...THEY WILL QUICKLY CLEAR OUT THIS MORNING. SKIES WILL
ALSO BECOME MOSTLY SUNNY E THIS AFTN. HIGHS TODAY WILL TOP OUT IN
THE 40S E TO AS HIGH AS THE LOWER 50S W WHERE WAA AND MORE SUN WILL
AID WARMING. PRES GRADIENT WILL QUICKLY TIGHTEN AFTER PASSAGE OF THE
HIGH PRES RIDGE AXIS AS A RAPIDLY DEEPENING SFC LOW TRACKING E TO
HUDSON BAY PUSHES AN ASSOCIATED TROF INTO THE WRN PLAINS. EXPECT S
WINDS TO ALREADY BEGIN TO SHOW SOME GUSTINESS DURING THE LATTER
PORTION OF THE AFTN OVER THE W HALF.
WINDS WILL THEN BE THE MAIN STORY TONIGHT. A DEEP SFC LOW OVER
HUDSON BAY...DROPPING TO A PRES OF AROUND 28.7 INCHES...WILL DRIVE
ASSOCIATED SFC TROF INTO MN. A 50+KT LOW-LEVEL JET WILL SHIFT INTO
UPPER MI DURING THE NIGHT. WHILE WAA AND NOCTURNAL COOLING WILL
RESULT IN CONSIDERABLE STABILITY PREVENTING ACCESS TO THE PEAK LOW-
LEVEL WINDS...MAX PRES FALLS OF AROUND 6MB/3HR SHIFTING ACROSS NRN
ONTARIO WILL AID AN INCREASE IN SFC WINDS/GUSTINESS...MAINLY IN THE
HIGH TERRAIN AND ESPECIALLY IN THE DOWNSLOPE AREAS NEAR LAKE
SUPERIOR AND ALONG NRN LAKE MI E OF ESCANABA. COULD BECOME FAIRLY
WINDY AT LEAST FOR A FEW HRS DURING THE TIME THAT THE ISALLOBARIC
WIND COMPONENT IS MAXIMIZED. WINDS WILL KEEP MIN TEMPS UP IN THE 30S
TO LWR 40S TONIGHT. INTERIOR SHELTERED LOCATIONS IN THE CNTRL AND E
MAY FALL TO THE LWR 30S.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 443 AM EDT SUN OCT 18 2015
TEMPERATURES THROUGH THE EXTENDED WILL BE NEAR TO SLIGHTLY ABOVE
NORMAL WITH A COUPLE CHANCES FOR RAINFALL.
MONDAY THROUGH TUESDAY...THE BROAD SURFACE RIDGE OVER THE MID
ATLANTIC STATES MONDAY WILL CONTINUE TO SLIDE TO THE SOUTHEAST. AS
THIS HAPPENS...A FAIRLY STRONG LOW PRESSURE SYSTEM OVER HUDSON BAY
WILL SLIDE INTO NORTHWEST QUEBEC. THERE WILL BE A FAIRLY STRONG
PRESSURE GRADIENT BETWEEN THE TWO SYSTEMS ALONG WITH A 40 TO 50 KNOT
LLJ...MAINLY OVER EASTERN LAKE SUPERIOR AND NORTHERN LAKE MICHIGAN
MONDAY MORNING BEFORE THE GRADIENT SLOWLY RELAXES DURING THE
AFTERNOON HOURS. THIS ALONG WITH DECENT MIXING IN THE LOWER LEVEL
WILL ALLOW FOR GUSTY SOUTHWEST WINDS...INCLUDING GALES ON LAKE
SUPERIOR AND LAKE MICHIGAN. ADDITIONALLY...THE LOW PRESSURE SYSTEM
HAS A WEAK TRAILING COLD FRONT STRETCHING FROM HUDSON BAY TO NEAR
THE ARROWHEAD OF MINNESOTA MONDAY MORNING. THIS FRONT WILL BECOME
MORE ENE TO WSW ORIENTED ACROSS THE AREA BEFORE QUICKLY SLIDING TO
THE SOUTH AND EAST OF THE AREA MONDAY NIGHT. THERE MAY BE A FEW RAIN
SHOWERS ALONG THE COLD FRONT BUT MOISTURE LOOKS TO BE FAIRLY LIMITED
AT THIS POINT AND FORCING LOOKS TO BE FAIRLY WEAK. HAVE ONLY KEPT
ISOLATED RAIN SHOWERS IN THE FORECAST FOR MONDAY. BEHIND THE COLD
FRONT...A SURFACE RIDGE...ZONAL TO SLIGHT UPPER LEVEL 500MB RIDGING
AND DRY AIR WILL BUILD INTO THE AREA LATE MONDAY NIGHT AND LINGER
THROUGH MUCH OF THE DAY TUESDAY BRINGING WARMER TEMPERATURES AND AN
END TO ANY ISOLATED SHOWERS THAT MAY DEVELOP MONDAY.
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...AS THE AFOREMENTIONED HIGH
PRESSURE SYSTEM SLIDES TO THE EAST OF THE AREA...A FAIRLY STRONG
SHORTWAVE AND SURFACE LOW DEVELOPING OVER SOUTHERN CANADA...WILL
BEGIN TO SLIDE EASTWARD TOWARD THE AREA TUESDAY NIGHT. IT LOOKS LIKE
THERE WILL BE ANOTHER...WEAKER...SHORTWAVE THAT SLIDES IN AHEAD OF
THE MAIN SHORTWAVE WHICH COULD HELP TO KICK UP SCATTERED RAIN
SHOWERS TUESDAY NIGHT...HOWEVER...THE BETTER FORCING WILL BE WITH
THE MUCH STRONGER SHORTWAVE PROGGED TO SLIDE ACROSS LAKE SUPERIOR
AND MUCH OF THE U.P. WEDNESDAY INTO WEDNESDAY NIGHT.
THURSDAY THROUGH THE EXTENDED...CONTINUED TO USE A CONSENSUS OF THE
MODELS THROUGH THIS TIME PERIOD. THE GENERAL TREND IS FOR A SURFACE
RIDGE AND ASSOCIATED UPPER LEVEL RIDGE TO BUILD INTO THE AREA
THURSDAY AND LINGER THROUGH THURSDAY NIGHT. THERE ARE SOME MODEL
DISAGREEMENTS BEYOND THAT. FRIDAY THE NEXT LOW PRESSURE
SYSTEM...DEVELOPING OVER THE PLAINS IS PROGGED TO PROGRESS SLOWLY
TOWARD THE EAST. THE GFS...AS IS TYPICAL FOR THIS TIME OF
YEAR...RUSHES THE LOW PRESSURE SYSTEM AND ASSOCIATED COLD FRONT
EASTWARD. THIS SOLUTION WOULD BRING PRECIPITATION INTO THE U.P.
FRIDAY AND RUSH IT OUT OF THE AREA BY SATURDAY MORNING. THE EC...IS
LESS PROGRESSIVE WITH THIS SYSTEM...WHICH KEEP THE HIGH PRESSURE IN
PLACE A BIT LONGER...KEEPING CONDITIONS DRY THROUGH FRIDAY
AFTERNOON. THE RAIN SHOWERS WITH THE EC SOLUTION WOULD THEN LINGER
THROUGH SATURDAY. THE REDUCED CONFIDENCE IN ANY ONE PARTICULAR MODEL
HAS LEANED THE FORECAST MORE TOWARD THE CONSENSUS OF THE MODELS
WHICH KEEPS CHANCE POPS IN THE FORECAST FRIDAY THROUGH SATURDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 137 AM EDT SUN OCT 18 2015
LOOK FOR VFR CONDITIONS TO PREVAIL AT KIWD/KCMX/KSAW THROUGH THE
FORECAST PERIOD AS HIGH PRESSURE BUILDS INTO THE REGION OVERNIGHT.
LINGERING CLOUD COVER ON NW FLOW WILL GRADUALLY ERODE AWAY AT KCMX
AND KSAW OVERNIGHT/EARLY MORNING AS RIDGE BUILDS IN...RESULTING IN
MOSTLY CLEAR SKIES THROUGH THE DAYLIGHT HOURS. LIGHT WINDS WILL
GRADUALLY INCREASE AS THE RIDGE SHIFTS EAST...WITH GUSTS TO 15 TO 20
KTS POSSIBLE FROM MID/LATE AFTERNOON INTO THE EVENING HOURS. WITH
WINDS INCREASING ALOFT...THERE IS A POTENTIAL FOR LLWS THIS
EVENING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 523 AM EDT SUN OCT 18 2015
HIGH PRES RIDGE WILL QUICKLY SHIFT ACROSS LAKE SUPERIOR TODAY...
RESULTING IN A BRIEF PERIOD OF LIGHT WINDS. ALREADY IN THE AFTN...
TIGHTENING PRES GRADIENT BEHIND THE RIDGE WILL LEAD TO INCREASING S
WINDS...GUSTING TO 20-25KT BY LATE AFTN. WINDS INCREASE FURTHER
TONIGHT AS A DEEP LOW TRACKS E OVER HUDSON BAY. WITH AN AREA OF MAX
PRES FALLS PASSING N OF THE LAKE...S TO SW WINDS WILL LIKELY REACH
GALE FORCE...ESPECIALLY BETWEEN ISLE ROYALE AND THE KEWEENAW...AND
OVER THE EASTERN PART OF THE LAKE WHERE THIS TYPE OF PATTERN
TYPICALLY PRODUCES THE STRONGEST WINDS. THE HIGHEST OBS PLATFORMS
WILL PROBABLY SEE WIND GUSTS IN EXCESS OF 40KT FOR A TIME.
WINDS WILL DIMINISH TO UNDER 25KT W TO E ON MON. AFTER A TROF PASSES
LATE MON AFTN AND EVENING...N TO NE WINDS WILL INCREASE TO 20-30KT
OVER MUCH OF THE LAKE AHEAD OF HIGH PRES THAT WILL BUILD SE INTO NRN
ONTARIO TUE. WINDS WILL THEN VEER TO THE E-SE TUE NIGHT/WED AS THE
HIGH MOVES INTO QUEBEC AND A LOW PRES TROF APPROACHES. AFTER THE
TROF PASSES...WINDS WILL FINALLY DIMINISH LATER THU WHEN HIGH PRES
BUILDS INTO THE UPPER GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 11 PM THIS EVENING TO 11 AM EDT MONDAY FOR
LSZ266-267.
GALE WARNING FROM 11 PM THIS EVENING TO 8 AM EDT MONDAY FOR
LSZ263-264.
LAKE MICHIGAN...
GALE WARNING FROM 1 AM TO 2 PM EDT MONDAY FOR LMZ221-248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KEC
AVIATION...RJT
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
100 PM CDT SUN OCT 18 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM CDT SUN OCT 18 2015
BIGGEST CONCERN IN THE SHORT TERM DEALS WITH FIRE WEATHER
TODAY...WITH WEST CENTRAL INTO SOUTH CENTRAL MN EXPECTED TO FLIRT
WITH RED FLAG WARNING CRITERIA.
SFC RIDGE TONIGHT IS CENTERED OVER WI...WITH SE RETURN FLOW QUICKLY
BECOMING ESTABLISHED ACROSS MN. THE MAIN THEME FOR TODAY WILL BE
STRONG WAA...AS H85 TEMPS WILL BE WARMING ABOUT 10C OVER WHAT WE SAW
YESTERDAY. THERE IS GOOD VISUAL EVIDENCE OF SAID WARM ADVECTION IN
THE FORM OF A BANK OF 6K-8K FT CLOUDS THAT HAVE FORMED OVER SRN MN
THIS MORNING. RAP 750MB RH ALONG WITH THE CLOUD FORECAST FROM THE
HRRR EVENTUALLY LATCHED ON TO THIS CLOUD COVER AND FOLLOWED THESE
MODEL FEATURES TO PUSH THAT AREA OF CLOUDS EAST ACROSS SRN MN INTO
WI THIS MORNING. BY THE AFTERNOON...THESE CLOUDS WILL BE EAST OF THE
MPX CWA AND OUR SKIES WILL REMAIN MAINLY CLEAR UNTIL UPPER LEVEL
CLOUDS CURRENTLY OVER CO/WY GET HERE TONIGHT.
THOUGH H85 TEMPS ARE WARMING 10C...WE WILL NOT BE MIXING THAT
DEEP...WITH NAM/RAP SOUNDINGS SHOWING THE BOUNDARY LAYER BUILDING TO
ABOUT 900 MB. MIXING TO THIS LEVEL PRODUCED HIGHS SIMILAR TO WHAT WE
HAD GOING...WITH UPPER 60S IN WRN MN AND UPPER 50S IN WRN WI. THESE
WARM TEMPERATURES COMBINED WITH DEWPS THIS MORNING IN THE 20S WOULD
PRODUCE HUMIDITIES UNDER 25 PERCENT...BUT THE GFS/NAM BOTH SUPPORT
DEEP ENOUGH MOISTURE ARRIVING WITH THE SE WINDS TO HELP PUSH DEWPS
THIS AFTERNOON UP INTO THE LOWER/MIDDLE 30S IN SOUTHERN/WESTERN
MN...WHICH IS JUST ENOUGH TO KEEP AFTERNOON HUMIDITIES ABOUT THE 25
PERCENT THRESHOLD FOR A RFW. STILL...WITH HUMIDITIES LIKELY DROPPING
UNDER 30 PERCENT ALONG WITH SE WINDS INCREASING TO BETWEEN 20 AND 25
MPH WITH GUSTS TO AROUND 30 MPH...WILL CONTINUE TO HEADLINE THE
INCREASED FIRE WEATHER THREAT IN THE FIRE WEATHER PLANNING FORECAST.
TONIGHT...SHORTWAVE ENERGY CURRENTLY OVER CO/WY WILL FLATTEN OUT THE
UPPER RIDGE MOVING OVERHEAD TODAY AND BRING A SLUG OF UPPER LEVEL
MOISTURE WITH AS WELL. HOWEVER...RH TIME-HEIGHT CROSS SECTIONS SHOW
THIS MOISTURE ONLY GETTING DOWN TO ABOUT 15K FT...SO NOT CONCERNED
ABOUT ANY PRECIP. HOWEVER...THESE CLOUDS ALONG WITH SOUTHERLY WINDS
REMAINING UP OVERNIGHT WILL RESULT IN A VERY MILD NIGHT
TONIGHT...WITH MUCH OF THE MN CWA SOUTH OF I-94 STAYING UP IN THE
50S.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 329 AM CDT SUN OCT 18 2015
THE LONG TERM STILL LOOKS TO START OUT ON A WARM NOTE MONDAY WITH
HIGHS AROUND 15 TO 20 DEGREES ABOVE CLIMATOLOGICAL NORMALS.
MEANWHILE...PRECIPITATION CHANCES CONTINUE TO WANE UNTIL CLOSER TO THE
END OF THE WEEK.
THE SURFACE COLD FRONT STILL LOOKS TO BE ON OUR WESTERN DOORSTEP
AT DAYBREAK MONDAY. FAVORABLE SOUTHWEST FLOW FOR WARMING WILL
ENSUE THROUGH MIDDAY ACROSS MUCH OF CENTRAL AND SOUTH CENTRAL MN.
H85 TEMPS IN THE UPPER TEENS /CELSIUS/ SHOULD YIELD UPPER 70S TO
NEAR 80 DEGREES OVER SOUTHWEST/SOUTH CENTRAL MN...WITH LOW/MID
70S ACROSS THE REMAINDER OF THE AREA. AT THIS POINT THE PROGGED
MOISTURE IS HARDLY SUFFICIENT TO GENERATE MUCH MORE THAN BROKEN
MID LEVEL CLOUD COVER ACROSS CENTRAL MN/WI...WITH VIRTUALLY NO
FORCING TO MENTION. HAVE THEREFORE REMOVED POPS FOR MONDAY.
TUESDAY AN INVERTED TROUGH NOSES INTO THE REGION...ALTHOUGH MODELS
ARE STILL ALL OVER THE MAP WITH REGARD TO POSITIONING. TWO AREAS
OF PRECIPITATION LOOK TO UNFOLD...WITH MODELS HINTING THE FORECAST
AREA COULD LARGELY BE PLACED BETWEEN SAID AREAS. HAVE INCLUDED
20-30 POPS FOR TUESDAY/WEDNESDAY...BUT ACTIVITY LOOKS AS IF IT
WOULD BE SCATTERED AT BEST WITH LOW PRECIP AMOUNTS.
WEDNESDAY NIGHT AND THURSDAY FLEETING SURFACE HIGH PRESSURE MOVES
ACROSS THE AREA...BUT THEN A STRONGER TROUGH WITH A NICE FETCH OF
MOISTURE ADVECTION LIFTS INTO THE AREA FOR FRIDAY. HAVE INCLUDED
40-50 POPS FOR FRIDAY AND FRIDAY NIGHT...DRYING OUT FOR SATURDAY.
HIGH TEMPERATURES FROM TUESDAY THROUGH THE LONG TERM FORECAST
PERIOD LOOK TO RUN AROUND 5 TO 10 DEGREES ABOVE NORMAL...WITH LOWS
EVEN WARMER IN THE 10 TO 15 DEGREES ABOVE NORMAL RANGE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 100 PM CDT SUN OCT 18 2015
ONLY SIGNIFICANT ISSUE IS WIND SHEAR TONIGHT. SHORT TERM MODELS
HAVE STRENGTHENED THE LOW LEVEL WIND EVEN EARLIER...SO MOST
LOCALES WILL SEE WIND SHEAR AS EARLY AS 03Z. MAY WELL HAVE OVER 60
KNOTS AT 1500-2500 FT AGL BY 06Z FROM SW MN INTO WESTERN WISC. IN
FACT...KRWF MAY SEE 60 KNOTS EVEN AS LOW AS 1200 FT AGL...THOUGH
THIS IS NOT CERTAIN. CORE OF STRONGEST WINDS WILL BE FROM SW MN
INTO WISC...BUT EVEN WEST CENTRAL MN WILL BE ON THE EDGE OF THIS
AND MAY WELL HAVE 50 KNOTS AT 2K TONIGHT. LOW LEVEL WIND SHEAR
WILL WEAKEN AS COLD FRONT APPROACHES. OTHERWISE JUST SOME CIRRUS
AND MAYBE SOME MID CLOUDS.
KMSP...SCATTERED CLOUDS AROUND 7K FT HAVE VIRTUALLY DISSIPATED.
ONLY ISSUE WILL BE WIND. MODELS ALL SHOW A STRONG JET DEVELOPING
THIS EVENING...WITH 50 KNOTS AT 2K AGL AS EARLY AS 03Z. SOME SHORT
TERM MODELS EVEN RAMP UP THE 2K AGL WIND TO 60 KNOTS BY 06Z. THUS
HAVE CONTINUED THE MENTION OF LOW LEVEL WIND SHEAR...BUT STARTED
IT EARLIER THAN PREVIOUSLY FORECAST. OTHERWISE JUST SOME CIRRUS
AND MAYBE MID LEVEL CLOUDS.
/OUTLOOK FOR KMSP/
MON...VFR. WINDS SW 15G25KTS
TUE...VFR. WINDS NE/E 5-10KTS.
WED...VFR. CHC MRNG SHRA. WINDS E BCMG NW 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...LS
AVIATION...TDK
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
650 AM CDT SUN OCT 18 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM CDT SUN OCT 18 2015
BIGGEST CONCERN IN THE SHORT TERM DEALS WITH FIRE WEATHER
TODAY...WITH WEST CENTRAL INTO SOUTH CENTRAL MN EXPECTED TO FLIRT
WITH RED FLAG WARNING CRITERIA.
SFC RIDGE TONIGHT IS CENTERED OVER WI...WITH SE RETURN FLOW QUICKLY
BECOMING ESTABLISHED ACROSS MN. THE MAIN THEME FOR TODAY WILL BE
STRONG WAA...AS H85 TEMPS WILL BE WARMING ABOUT 10C OVER WHAT WE SAW
YESTERDAY. THERE IS GOOD VISUAL EVIDENCE OF SAID WARM ADVECTION IN
THE FORM OF A BANK OF 6K-8K FT CLOUDS THAT HAVE FORMED OVER SRN MN
THIS MORNING. RAP 750MB RH ALONG WITH THE CLOUD FORECAST FROM THE
HRRR EVENTUALLY LATCHED ON TO THIS CLOUD COVER AND FOLLOWED THESE
MODEL FEATURES TO PUSH THAT AREA OF CLOUDS EAST ACROSS SRN MN INTO
WI THIS MORNING. BY THE AFTERNOON...THESE CLOUDS WILL BE EAST OF THE
MPX CWA AND OUR SKIES WILL REMAIN MAINLY CLEAR UNTIL UPPER LEVEL
CLOUDS CURRENTLY OVER CO/WY GET HERE TONIGHT.
THOUGH H85 TEMPS ARE WARMING 10C...WE WILL NOT BE MIXING THAT
DEEP...WITH NAM/RAP SOUNDINGS SHOWING THE BOUNDARY LAYER BUILDING TO
ABOUT 900 MB. MIXING TO THIS LEVEL PRODUCED HIGHS SIMILAR TO WHAT WE
HAD GOING...WITH UPPER 60S IN WRN MN AND UPPER 50S IN WRN WI. THESE
WARM TEMPERATURES COMBINED WITH DEWPS THIS MORNING IN THE 20S WOULD
PRODUCE HUMIDITIES UNDER 25 PERCENT...BUT THE GFS/NAM BOTH SUPPORT
DEEP ENOUGH MOISTURE ARRIVING WITH THE SE WINDS TO HELP PUSH DEWPS
THIS AFTERNOON UP INTO THE LOWER/MIDDLE 30S IN SOUTHERN/WESTERN
MN...WHICH IS JUST ENOUGH TO KEEP AFTERNOON HUMIDITIES ABOUT THE 25
PERCENT THRESHOLD FOR A RFW. STILL...WITH HUMIDITIES LIKELY DROPPING
UNDER 30 PERCENT ALONG WITH SE WINDS INCREASING TO BETWEEN 20 AND 25
MPH WITH GUSTS TO AROUND 30 MPH...WILL CONTINUE TO HEADLINE THE
INCREASED FIRE WEATHER THREAT IN THE FIRE WEATHER PLANNING FORECAST.
TONIGHT...SHORTWAVE ENERGY CURRENTLY OVER CO/WY WILL FLATTEN OUT THE
UPPER RIDGE MOVING OVERHEAD TODAY AND BRING A SLUG OF UPPER LEVEL
MOISTURE WITH AS WELL. HOWEVER...RH TIME-HEIGHT CROSS SECTIONS SHOW
THIS MOISTURE ONLY GETTING DOWN TO ABOUT 15K FT...SO NOT CONCERNED
ABOUT ANY PRECIP. HOWEVER...THESE CLOUDS ALONG WITH SOUTHERLY WINDS
REMAINING UP OVERNIGHT WILL RESULT IN A VERY MILD NIGHT
TONIGHT...WITH MUCH OF THE MN CWA SOUTH OF I-94 STAYING UP IN THE
50S.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 329 AM CDT SUN OCT 18 2015
THE LONG TERM STILL LOOKS TO START OUT ON A WARM NOTE MONDAY WITH
HIGHS AROUND 15 TO 20 DEGREES ABOVE CLIMATOLOGICAL NORMALS.
MEANWHILE...PRECIPITATION CHANCES CONTINUE TO WANE UNTIL CLOSER TO THE
END OF THE WEEK.
THE SURFACE COLD FRONT STILL LOOKS TO BE ON OUR WESTERN DOORSTEP
AT DAYBREAK MONDAY. FAVORABLE SOUTHWEST FLOW FOR WARMING WILL
ENSUE THROUGH MIDDAY ACROSS MUCH OF CENTRAL AND SOUTH CENTRAL MN.
H85 TEMPS IN THE UPPER TEENS /CELSIUS/ SHOULD YIELD UPPER 70S TO
NEAR 80 DEGREES OVER SOUTHWEST/SOUTH CENTRAL MN...WITH LOW/MID
70S ACROSS THE REMAINDER OF THE AREA. AT THIS POINT THE PROGGED
MOISTURE IS HARDLY SUFFICIENT TO GENERATE MUCH MORE THAN BROKEN
MID LEVEL CLOUD COVER ACROSS CENTRAL MN/WI...WITH VIRTUALLY NO
FORCING TO MENTION. HAVE THEREFORE REMOVED POPS FOR MONDAY.
TUESDAY AN INVERTED TROUGH NOSES INTO THE REGION...ALTHOUGH MODELS
ARE STILL ALL OVER THE MAP WITH REGARD TO POSITIONING. TWO AREAS
OF PRECIPITATION LOOK TO UNFOLD...WITH MODELS HINTING THE FORECAST
AREA COULD LARGELY BE PLACED BETWEEN SAID AREAS. HAVE INCLUDED
20-30 POPS FOR TUESDAY/WEDNESDAY...BUT ACTIVITY LOOKS AS IF IT
WOULD BE SCATTERED AT BEST WITH LOW PRECIP AMOUNTS.
WEDNESDAY NIGHT AND THURSDAY FLEETING SURFACE HIGH PRESSURE MOVES
ACROSS THE AREA...BUT THEN A STRONGER TROUGH WITH A NICE FETCH OF
MOISTURE ADVECTION LIFTS INTO THE AREA FOR FRIDAY. HAVE INCLUDED
40-50 POPS FOR FRIDAY AND FRIDAY NIGHT...DRYING OUT FOR SATURDAY.
HIGH TEMPERATURES FROM TUESDAY THROUGH THE LONG TERM FORECAST
PERIOD LOOK TO RUN AROUND 5 TO 10 DEGREES ABOVE NORMAL...WITH LOWS
EVEN WARMER IN THE 10 TO 15 DEGREES ABOVE NORMAL RANGE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 650 AM CDT SUN OCT 18 2015
ONLY CHANGES MADE TO EXISTING TAFS WAS TO ADD A BRIEF FOG MENTION
AT EAU THIS MORNING AND ADD IN WIND SHEAR FOR TONIGHT. FOR
EAU...THIS IS SIMPLY YOUR RADIATIVE COOLING RIVER FOG. 1330 IS
PROBABLY A LITTLE TOO LONG TO HOLD THE FOG...BUT WILL KEEP US FROM
HAVING TO CHASE THE IMPROVEMENT. TONIGHT...WE WILL SEE A 55-60KT
LLJ CENTERED AT ABOUT 2500 FEET MOVE UP FROM SW MN TOWARD NW WI.
DIRECTIONAL SHEAR WITH THE JET IS NOT ALL THAT GREAT...BUT THE
SPEED SHEAR NEAR THE NOSE OF THE NOCTURNAL INVERSION WILL BE QUITE
STRONG...SO ADDED WIND SHEAR TO ALL BUT STC/AXN AS THE CORE OF THE
LLJ LOOKS TO COME IN EAST OF THESE LOCATIONS.
KMSP...7K FT CIGS SOUTH OF THE FIELD LOOK TO STAY SOUTH OF
MSP...THOUGH A STRAY CLOUD UP AROUND THIS LEVEL THROUGH THE
MORNING CAN NOT BE RULED OUT. BOTH THE GFS/NAM SHOW A STRONG JET
DEVELOPING AT THE NOSE OF THE LLJ TONIGHT...SO FELT COMFORTABLE
WITH GOING WITH THE WIND SHEAR MENTION THIS FAR OUT.
/OUTLOOK FOR KMSP/
MON...VFR. WINDS SW 15G25KTS
TUE...VFR. WINDS NE/E 5-10KTS.
WED...VFR. CHC MRNG SHRA. WINDS E BCMG NW 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...LS
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
329 AM CDT SUN OCT 18 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM CDT SUN OCT 18 2015
BIGGEST CONCERN IN THE SHORT TERM DEALS WITH FIRE WEATHER
TODAY...WITH WEST CENTRAL INTO SOUTH CENTRAL MN EXPECTED TO FLIRT
WITH RED FLAG WARNING CRITERIA.
SFC RIDGE TONIGHT IS CENTERED OVER WI...WITH SE RETURN FLOW QUICKLY
BECOMING ESTABLISHED ACROSS MN. THE MAIN THEME FOR TODAY WILL BE
STRONG WAA...AS H85 TEMPS WILL BE WARMING ABOUT 10C OVER WHAT WE SAW
YESTERDAY. THERE IS GOOD VISUAL EVIDENCE OF SAID WARM ADVECTION IN
THE FORM OF A BANK OF 6K-8K FT CLOUDS THAT HAVE FORMED OVER SRN MN
THIS MORNING. RAP 750MB RH ALONG WITH THE CLOUD FORECAST FROM THE
HRRR EVENTUALLY LATCHED ON TO THIS CLOUD COVER AND FOLLOWED THESE
MODEL FEATURES TO PUSH THAT AREA OF CLOUDS EAST ACROSS SRN MN INTO
WI THIS MORNING. BY THE AFTERNOON...THESE CLOUDS WILL BE EAST OF THE
MPX CWA AND OUR SKIES WILL REMAIN MAINLY CLEAR UNTIL UPPER LEVEL
CLOUDS CURRENTLY OVER CO/WY GET HERE TONIGHT.
THOUGH H85 TEMPS ARE WARMING 10C...WE WILL NOT BE MIXING THAT
DEEP...WITH NAM/RAP SOUNDINGS SHOWING THE BOUNDARY LAYER BUILDING TO
ABOUT 900 MB. MIXING TO THIS LEVEL PRODUCED HIGHS SIMILAR TO WHAT WE
HAD GOING...WITH UPPER 60S IN WRN MN AND UPPER 50S IN WRN WI. THESE
WARM TEMPERATURES COMBINED WITH DEWPS THIS MORNING IN THE 20S WOULD
PRODUCE HUMIDITIES UNDER 25 PERCENT...BUT THE GFS/NAM BOTH SUPPORT
DEEP ENOUGH MOISTURE ARRIVING WITH THE SE WINDS TO HELP PUSH DEWPS
THIS AFTERNOON UP INTO THE LOWER/MIDDLE 30S IN SOUTHERN/WESTERN
MN...WHICH IS JUST ENOUGH TO KEEP AFTERNOON HUMIDITIES ABOUT THE 25
PERCENT THRESHOLD FOR A RFW. STILL...WITH HUMIDITIES LIKELY DROPPING
UNDER 30 PERCENT ALONG WITH SE WINDS INCREASING TO BETWEEN 20 AND 25
MPH WITH GUSTS TO AROUND 30 MPH...WILL CONTINUE TO HEADLINE THE
INCREASED FIRE WEATHER THREAT IN THE FIRE WEATHER PLANNING FORECAST.
TONIGHT...SHORTWAVE ENERGY CURRENTLY OVER CO/WY WILL FLATTEN OUT THE
UPPER RIDGE MOVING OVERHEAD TODAY AND BRING A SLUG OF UPPER LEVEL
MOISTURE WITH AS WELL. HOWEVER...RH TIME-HEIGHT CROSS SECTIONS SHOW
THIS MOISTURE ONLY GETTING DOWN TO ABOUT 15K FT...SO NOT CONCERNED
ABOUT ANY PRECIP. HOWEVER...THESE CLOUDS ALONG WITH SOUTHERLY WINDS
REMAINING UP OVERNIGHT WILL RESULT IN A VERY MILD NIGHT
TONIGHT...WITH MUCH OF THE MN CWA SOUTH OF I-94 STAYING UP IN THE
50S.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 329 AM CDT SUN OCT 18 2015
THE LONG TERM STILL LOOKS TO START OUT ON A WARM NOTE MONDAY WITH
HIGHS AROUND 15 TO 20 DEGREES ABOVE CLIMATOLOGICAL NORMALS.
MEANWHILE...PRECIPITATION CHANCES CONTINUE TO WANE UNTIL CLOSER TO THE
END OF THE WEEK.
THE SURFACE COLD FRONT STILL LOOKS TO BE ON OUR WESTERN DOORSTEP
AT DAYBREAK MONDAY. FAVORABLE SOUTHWEST FLOW FOR WARMING WILL
ENSUE THROUGH MIDDAY ACROSS MUCH OF CENTRAL AND SOUTH CENTRAL MN.
H85 TEMPS IN THE UPPER TEENS /CELSIUS/ SHOULD YIELD UPPER 70S TO
NEAR 80 DEGREES OVER SOUTHWEST/SOUTH CENTRAL MN...WITH LOW/MID
70S ACROSS THE REMAINDER OF THE AREA. AT THIS POINT THE PROGGED
MOISTURE IS HARDLY SUFFICIENT TO GENERATE MUCH MORE THAN BROKEN
MID LEVEL CLOUD COVER ACROSS CENTRAL MN/WI...WITH VIRTUALLY NO
FORCING TO MENTION. HAVE THEREFORE REMOVED POPS FOR MONDAY.
TUESDAY AN INVERTED TROUGH NOSES INTO THE REGION...ALTHOUGH MODELS
ARE STILL ALL OVER THE MAP WITH REGARD TO POSITIONING. TWO AREAS
OF PRECIPITATION LOOK TO UNFOLD...WITH MODELS HINTING THE FORECAST
AREA COULD LARGELY BE PLACED BETWEEN SAID AREAS. HAVE INCLUDED
20-30 POPS FOR TUESDAY/WEDNESDAY...BUT ACTIVITY LOOKS AS IF IT
WOULD BE SCATTERED AT BEST WITH LOW PRECIP AMOUNTS.
WEDNESDAY NIGHT AND THURSDAY FLEETING SURFACE HIGH PRESSURE MOVES
ACROSS THE AREA...BUT THEN A STRONGER TROUGH WITH A NICE FETCH OF
MOISTURE ADVECTION LIFTS INTO THE AREA FOR FRIDAY. HAVE INCLUDED
40-50 POPS FOR FRIDAY AND FRIDAY NIGHT...DRYING OUT FOR SATURDAY.
HIGH TEMPERATURES FROM TUESDAY THROUGH THE LONG TERM FORECAST
PERIOD LOOK TO RUN AROUND 5 TO 10 DEGREES ABOVE NORMAL...WITH LOWS
EVEN WARMER IN THE 10 TO 15 DEGREES ABOVE NORMAL RANGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1249 AM CDT SUN OCT 18 2015
DRY SFC HIGH WILL DOMINATE THIS TAF PERIOD. SE RETURN FLOW ALREADY
SETUP OUT IN WRN MN AND WILL WORK INTO WRN WI SHORTLY AFTER
SUNRISE. STRONG PRESSURE GRADIENT WILL SETUP AND FORECAST
SOUNDINGS FULLY SUPPORT LAV GUIDANCE WINDS...SO FOLLOWED THOSE
NUMBERS FOR RAMPING UP WINDS LATER TODAY. RAP 750MB RH HAS A GOOD
HANDLE ON CLOUDS EXPANDING ACROSS SRN MN AT AROUND 7K FT. THIS
AREA OF WARM ADVECTIVE CLOUDS WILL WORK EAST THROUGH THE
MORNING...POSSIBLY CLIPPING MSP/EAU.
KMSP...ONLY QUESTION MARK FOR THIS TAF IS DO 7K-8K FT CLOUDS SW
OF MSP REACH THE FIELD. KEPT THEM OUT...BUT RAP 750MB RH WOULD SAY
WE SEE SOME CLOUDS AT THIS LEVEL BETWEEN 8Z AND 18Z.
/OUTLOOK FOR KMSP/
MON...VFR. LLWS PSBL IN MRNG. WINDS SW 15G25KTS
TUE...VFR. WINDS NE/E 5-10KTS.
WED...VFR. CHC MRNG SHRA. WINDS E BCMG NW 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...LS
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1250 AM CDT SUN OCT 18 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 330 PM CDT SAT OCT 17 2015
DRY...COOL AND QUIET WEATHER IS EXPECTED TONIGHT...BUT THERE IS
CHANGE AFOOT. RIDGE OF HIGH PRESSURE EXTENDING FROM CENTRAL IOWA TO
SOUTHEASTERN MANITOBA WILL CROSS MINNESOTA THIS EVENING...AND REACH
WESTERN WISCONSIN LATER THIS EVENING. RETURN FLOW HAS ALREADY
STARTED IN FAR WESTERN MN...AND THE ENTIRE AREA WILL HAVE SSE WINDS
TOMORROW. WITH LOW PRESSURE EXPECTED TO STILL BE IN THE NORTHERN
HIGH PLAINS...A DECENT GRADIENT WILL DEVELOP. WINDS IN WESTERN MN
SHOULD REV UP AND PRODUCE GUSTS OF 25-30 KNOTS FROM WEST CENTRAL TO
SOUTH CENTRAL MN. RIGHT NOW IT LOOKS LIKE HIGHS WILL BE IN THE LOWER
TO MID 60S. DEW POINTS ARE THE MAIN CONCERN AT THIS TIME IN TERMS OF
FIRE WEATHER. LOW LEVEL MOISTURE IS SLIGHTLY GREATER TO OUR
SOUTHWEST...AND THEREFORE THINK DEW POINTS IN OUR WESTERN COUNTIES
TOMORROW WILL RISE A TAD INTO THE LOWER 30S...RESULTING IN MINIMUM
HUMIDITIES ON THE ORDER OF 28-32 PERCENT. IF THIS CHANGES VERY
MUCH... THEN FIRE WEATHER HIGHLIGHTS MAY BE IN ORDER.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 330 PM CDT SAT OCT 17 2015
THE MAIN CONCERNS IN THE LONG TERM REMAIN HOW WARM IT WILL GET
MONDAY AFTERNOON AND THE OVERALL DEVELOPMENT/MOVEMENT OF NEXT
WAVE FOR TUE THROUGH WED MORNING...AND AGAIN LATE IN THE WEEK INTO
THE WEEKEND.
STILL HAVE A DECENT THERMAL RIDGE AHEAD OF THE FRONT ON MONDAY
AFTERNOON. QUESTION REMAINS HOW MUCH CLOUD COVER WE WILL WORK
OVER THE REGION WITH THE SYSTEM. WILL LIKELY SEE SOME MID/HIGH
LEVEL CLOUDS MOVE ACROSS THE AREA...THICKER TO THE EAST.
MAINTAINED A SMALL CHANCE FOR SHOWERS INTO THE NORTHEAST CWA WHERE
LIMITED FORCING IS LOCATED. THE GFS IS CONSISTENT WITH THE
MID/UPPER 70S TO THE SOUTHWEST AND SOME UPPER 60S TO LOWER 70S
ELSEWHERE. SOUTHWEST FLOW WILL REMAIN STRONG AHEAD OF THE FRONT
AND WITH DEWPOINTS REMAINING FAIRLY DRY...WE WILL LIKELY SEE
RELATIVE HUMIDITY DROP OFF TO 25 TO 30 PERCENT AGAIN MONDAY
AFTERNOON OVER MAINLY SOUTH CENTRAL MINNESOTA. MENTIONED THIS
CONCERN IN THE FIRE WEATHER FORECAST.
THE FRONT DROPS SOUTH OF THE AREA INTO MONDAY NIGHT AND UPPER
LEVEL FLOW DOES MERGE A BIT OVER THE AREA TUESDAY-WEDNESDAY. WILL
CONTINUE A CHANCE FOR -SHRA WITH THIS AS IT MOVES THROUGH.
MOISTURE WILL BE LIMITED HOWEVER.
ABOVE NORMAL TEMPERATURES REMAIN OVER THE AREA THROUGH THE
REMAINDER OF THE FORECAST. THE NEXT BEST SHOT FOR SHOWERS ARRIVES
LATE IN THE WEEK AND LINGERING INTO SATURDAY. WE MAY SEE A LITTLE
DEEPER MOISTURE RETURN AS FLOW BECOMES MORE SOUTHWEST ALOFT AND
PWATS INCREASE TO NEAR 1.4 INCHES BY SATURDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1249 AM CDT SUN OCT 18 2015
DRY SFC HIGH WILL DOMINATE THIS TAF PERIOD. SE RETURN FLOW ALREADY
SETUP OUT IN WRN MN AND WILL WORK INTO WRN WI SHORTLY AFTER
SUNRISE. STRONG PRESSURE GRADIENT WILL SETUP AND FORECAST
SOUNDINGS FULLY SUPPORT LAV GUIDANCE WINDS...SO FOLLOWED THOSE
NUMBERS FOR RAMPING UP WINDS LATER TODAY. RAP 750MB RH HAS A GOOD
HANDEL ON CLOUDS EXPANDING ACROSS SRN MN AT AROUND 7K FT. THIS
AREA OF WARM ADVECTIVE CLOUDS WILL WORK EAST THROUGH THE
MORNING...POSSIBLY CLIPPING MSP/EAU.
KMSP...ONLY QUESTION MARK FOR THIS TAF IS DO 7K-8K FT CLOUDS SW
OF MSP REACH THE FIELD. KEPT THEM OUT...BUT RAP 750MB RH WOULD SAY
WE SEE SOME CLOUDS AT THIS LEVEL BETWEEN 8Z AND 18Z.
/OUTLOOK FOR KMSP/
MON...VFR. LLWS PSBL IN MRNG. WINDS SW 15G25KTS
TUE...VFR. WINDS NE/E 5-10KTS.
WED...VFR. CHC MRNG SHRA. WINDS E BCMG NW 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...TDK
LONG TERM...DWE
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS BILLINGS MT
901 PM MDT MON OCT 19 2015
.UPDATE...
ONLY MINOR CHANGES FOR THE UPDATE THIS HOUR TO ADJUST PRECIP
TRENDS BASED ON LATEST RADAR TRENDS. LIGHT TO MODERATE RAINS
WIDESPREAD FOR AREAS OF SOUTH CENTRAL MT AHEAD OF SHORT WAVE
ENERGY LIFTING NORTH INTO FAR SOUTHERN MT THIS EVENING. HRRR HAS A
PRETTY GOOD HANDLE ON THE CURRENT SITUATION...KEEPING A
DEFORMATION ZONE OF LINGERING LIGHT RAINS CLOSE TO OR TO THE
NORTHWEST OF BILLINGS INTO THE OVERNIGHT HOURS. APPEARS AS THOUGH
SOUTHEAST MT HAS THE LOWEST CHANCES OVERNIGHT IN AN AREA OF DRY
SLOTTING LATER TONIGHT. FRIEDERS
&&
.SHORT TERM...VALID FOR TUE AND WED...
SPLIT FLOW TROUGH OVER THE INTERMOUNTAIN WEST DOWN INTO SOUTHERN
CALIFORNIA WILL BE THE WEATHER MAKER FOR US OVER THE NEXT 24-30
HOURS. SOME OF THE ENERGY FROM NEVADA/IDAHO IS PROGGED TO DRIFT
THROUGH MONTANA INTO THE NORTHERN STREAM...WHILE OTHER VORT ENERGY
DROPS SOUTH INTO THE BAJA. THIS GENERALLY LEADS TO A DISORGANIZED
TROUGH AFFECTING OUR REGION TONIGHT AND TOMORROW. THAT
SAID...THERE IS STILL PLENTY OF LARGE SCALE LIFT TO OCCUR INDUCED
BY HEIGHT FALLS AND WIDESPREAD Q VECTOR FORCING.
PREVIOUS DISCUSSIONS HAVE LAID ALL THIS OUT AND WE FIND ONLY
TWEAKS TO OUR WIDESPREAD POPS NECESSARY FOR THIS PACKAGE. BEST
CHANCE OF DECENT SHOWERS OVER MOUNTAINS SEEMS TO BE LATE TODAY AND
AGAIN ABOUT MID MORNING TUESDAY. FOR BILLINGS ITSELF...BEST SHOT
OF MEASURABLE RAINFALL IS THIS EVENING. INSTABILITY INDICES STILL
SUGGEST A CHANCE OF THUNDER WITH THE SHOWERS THIS EVENING OVER THE
SOUTHERN AND EASTERN ZONES.
SHOWERS SHOULD QUICKLY END LATE TOMORROW/TOMORROW EVENING BEHIND
THE TROUGH AXIS WITH DOWNWARD MOTION SPREADING OVER THE REGION.
WEDNESDAY LOOKS LIKE A DRY SEASONAL DAY WITH RIDGING OVER OUR
REGION. BT
.LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON...
FORECAST LOOKS ON TRACK AND DID NOT MAKE MANY CHANGES. DID RAISE
POPS A BIT FOR THE EAST ON THURSDAY AND THURSDAY NIGHT. BOTH
MODELS TAKE ENERGY FROM THE UPPER LOW OVER COLORADO AND LIFT IT
INTO SOUTHEAST MONTANA THURSDAY AND THURSDAY NIGHT. THE GFS HAS
TRENDED A LITTLE FARTHER WEST WITH THIS SOLUTION AND IS MORE IN
LINE WITH THE ECMWF...THUS RAISED POPS.
NORTHWEST FLOW TAKES OVER FOR FRIDAY AND SATURDAY. WEAK ENERGY
WILL SWEEP ACROSS MONTANA FRIDAY...AND THUS WILL LEAVE POPS IN THE
FORECAST. THE MODELS THEN DIVERGE FOR SUNDAY AND MONDAY. THE ECMWF
SWEEPS A DECENT SHORTWAVE ACROSS SUNDAY AND SUNDAY NIGHT...WHILE
THE GFS WAS MUCH FLATTER WITH THE FLOW...BUT STILL TAKES ENERGY
ACROSS MONTANA. HAVE DECIDED TO ADD POPS FOR THE SUNDAY NIGHT.
TEMPERATURES WILL BE MILD DURING THE PERIOD. TWH
&&
.AVIATION...
SHOWERS WILL SPREAD ACROSS THE AREA THROUGH THE NIGHT. MAINLY VFR
CONDITIONS WILL PREVAIL...WITH LOCALIZED MVFR CONDITIONS POSSIBLE IN
HEAVIER SHOWERS. MOUNTAINS WILL BE FREQUENTLY OBSCURED. AAG
&&
.PRELIMINARY POINT TEMP/POPS...
TUE WED THU FRI SAT SUN MON
-----------------------------------------------------------
BIL 049/062 039/064 041/066 041/058 035/058 036/061 038/062
+3/W 10/U 00/U 22/W 11/B 11/B 21/B
LVM 044/056 034/064 038/065 033/054 031/058 033/061 035/062
+7/W 10/U 00/U 22/W 11/B 11/B 21/B
HDN 045/064 035/066 037/068 038/060 032/061 032/063 034/065
+3/W 10/U 00/B 21/B 11/B 11/B 21/B
MLS 047/063 036/063 039/066 041/058 036/058 036/061 036/061
63/W 10/U 01/B 52/W 11/B 01/B 21/B
4BQ 046/063 034/062 040/065 040/058 034/059 034/062 035/062
32/W 10/U 03/W 42/W 11/B 11/B 21/B
BHK 044/063 034/060 035/065 040/057 033/056 032/059 032/058
32/W 10/U 03/W 52/W 11/B 01/B 21/B
SHR 043/062 036/063 037/066 039/057 033/058 032/062 035/064
32/W 10/U 02/W 32/W 21/B 11/B 21/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
608 PM MDT MON OCT 19 2015
.UPDATE...
EARLY UPDATE THIS EVENING AS SHOWERS BECOMING WIDESPREAD ACROSS
NORTHERN WY AND SOUTH CENTRAL MT AHEAD APPROACHING SHORT WAVE
ENERGY LIFTING NORTH OUT OF CENTRAL WY. HRRR HAS A PRETTY GOOD
HANDLE ON THE CURRENT SITUATION AND WOULD EXPECT THIS INCREASE IN
SHOWERS TO CONTINUE ACROSS THE WESTERN HALF OF THE REGION THIS
EVENING. LIGHT RAINS LOOK TO LINGER ACROSS AREAS MAINLY NW OF
BILLINGS INTO OVERNIGHT HOURS. APPEARS AS THOUGH SOUTHEAST MT HAS
THE LOWEST CHANCES OVERNIGHT AFTER SOME LIGHT SHOWERS MOVE THROUGH
THAT AREA THIS EVENING. HAVE RAISED PRECIP CHANCES IN THE SOUTH
CENTRAL MT AREAS TO ACCOUNT FOR CURRENT TRENDS. FRIEDERS
&&
.SHORT TERM...VALID FOR TUE AND WED...
SPLIT FLOW TROUGH OVER THE INTERMOUNTAIN WEST DOWN INTO SOUTHERN
CALIFORNIA WILL BE THE WEATHER MAKER FOR US OVER THE NEXT 24-30
HOURS. SOME OF THE ENERGY FROM NEVADA/IDAHO IS PROGGED TO DRIFT
THROUGH MONTANA INTO THE NORTHERN STREAM...WHILE OTHER VORT ENERGY
DROPS SOUTH INTO THE BAJA. THIS GENERALLY LEADS TO A DISORGANIZED
TROUGH AFFECTING OUR REGION TONIGHT AND TOMORROW. THAT
SAID...THERE IS STILL PLENTY OF LARGE SCALE LIFT TO OCCUR INDUCED
BY HEIGHT FALLS AND WIDESPREAD Q VECTOR FORCING.
PREVIOUS DISCUSSIONS HAVE LAID ALL THIS OUT AND WE FIND ONLY
TWEAKS TO OUR WIDESPREAD POPS NECESSARY FOR THIS PACKAGE. BEST
CHANCE OF DECENT SHOWERS OVER MOUNTAINS SEEMS TO BE LATE TODAY AND
AGAIN ABOUT MID MORNING TUESDAY. FOR BILLINGS ITSELF...BEST SHOT
OF MEASURABLE RAINFALL IS THIS EVENING. INSTABILITY INDICES STILL
SUGGEST A CHANCE OF THUNDER WITH THE SHOWERS THIS EVENING OVER THE
SOUTHERN AND EASTERN ZONES.
SHOWERS SHOULD QUICKLY END LATE TOMORROW/TOMORROW EVENING BEHIND
THE TROUGH AXIS WITH DOWNWARD MOTION SPREADING OVER THE REGION.
WEDNESDAY LOOKS LIKE A DRY SEASONAL DAY WITH RIDGING OVER OUR
REGION. BT
.LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON...
FORECAST LOOKS ON TRACK AND DID NOT MAKE MANY CHANGES. DID RAISE
POPS A BIT FOR THE EAST ON THURSDAY AND THURSDAY NIGHT. BOTH
MODELS TAKE ENERGY FROM THE UPPER LOW OVER COLORADO AND LIFT IT
INTO SOUTHEAST MONTANA THURSDAY AND THURSDAY NIGHT. THE GFS HAS
TRENDED A LITTLE FARTHER WEST WITH THIS SOLUTION AND IS MORE IN
LINE WITH THE ECMWF...THUS RAISED POPS.
NORTHWEST FLOW TAKES OVER FOR FRIDAY AND SATURDAY. WEAK ENERGY
WILL SWEEP ACROSS MONTANA FRIDAY...AND THUS WILL LEAVE POPS IN THE
FORECAST. THE MODELS THEN DIVERGE FOR SUNDAY AND MONDAY. THE ECMWF
SWEEPS A DECENT SHORTWAVE ACROSS SUNDAY AND SUNDAY NIGHT...WHILE
THE GFS WAS MUCH FLATTER WITH THE FLOW...BUT STILL TAKES ENERGY
ACROSS MONTANA. HAVE DECIDED TO ADD POPS FOR THE SUNDAY NIGHT.
TEMPERATURES WILL BE MILD DURING THE PERIOD. TWH
&&
.AVIATION...
SCATTERED SHOWERS WILL SPREAD ACROSS THE AREA THIS EVENING. THERE
IS A SLIGHT CHANCE OF A THUNDERSTORM SOUTHEAST OF KBIL THIS
EVENING. VFR CONDITIONS WILL PREVAIL WITH ISOLATED MVFR IN THE
HEAVIER SHOWERS. MOUNTAINS WILL BE FREQUENTLY OBSCURED. TWH
&&
.PRELIMINARY POINT TEMP/POPS...
TUE WED THU FRI SAT SUN MON
-----------------------------------------------------------
BIL 049/062 039/064 041/066 041/058 035/058 036/061 038/062
93/W 10/U 00/U 22/W 11/B 11/B 21/B
LVM 044/056 034/064 038/065 033/054 031/058 033/061 035/062
+7/W 10/U 00/U 22/W 11/B 11/B 21/B
HDN 045/064 035/066 037/068 038/060 032/061 032/063 034/065
93/W 10/U 00/B 21/B 11/B 11/B 21/B
MLS 047/063 036/063 039/066 041/058 036/058 036/061 036/061
43/W 10/U 01/B 52/W 11/B 01/B 21/B
4BQ 046/063 034/062 040/065 040/058 034/059 034/062 035/062
42/W 10/U 03/W 42/W 11/B 11/B 21/B
BHK 044/063 034/060 035/065 040/057 033/056 032/059 032/058
32/W 10/U 03/W 52/W 11/B 01/B 21/B
SHR 043/062 036/063 037/066 039/057 033/058 032/062 035/064
52/W 10/U 02/W 32/W 21/B 11/B 21/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
1005 AM PDT SUN OCT 18 2015
.SYNOPSIS...A BROAD LOW PRESSURE SYSTEM MOVING ACROSS CALIFORNIA AND
NEVADA WILL BRING WIDESPREAD SHOWERS AND SCATTERED THUNDERSTORMS
TODAY...ALONG WITH A THREAT OF FLASH FLOODING. ADDITIONAL UPPER
LEVEL DISTURBANCES WILL CONTINUE TO PROVIDE UNSETTLED AND COOL
CONDITIONS INTO THE MIDDLE OF NEXT WEEK.
&&
.UPDATE...THE LATEST SATELLITE AND RADAR TRENDS INDICATE CONVECTION
IS DEVELOPING PRETTY CLOSELY TO HOW INHERITED POP/WX GRIDS DEPICT. A
TRAIN OF THUNDERSTORMS HAS BEEN PERSISTING FROM DEATH VALLEY
JUNCTION UP THROUGH AMARGOSA VALLEY AND THE NEVADA NATIONAL SECURITY
SITE. RECENT HRRR RUNS DEPICT A LINE OF CONVECTION DEVELOPING FROM
MOUNTAIN PASS IN CALIFORNIA UP THROUGH CENTRAL AND NORTHEAST CLARK
COUNTY BETWEEN 19Z AND 23Z. ONLY MINOR ADJUSTMENTS WERE MADE TO THE
POP/WX GRIDS TO INCREASE STORM COVERAGE TO SCATTERED DOWN TO BARSTOW
AND TWENTYNINE PALMS THIS AFTERNOON. THE REST OF THE TRENDS DETAILED
IN THE PREVIOUS DISCUSSION LOOK OKAY.
&&
.AVIATION...FOR MCCARRAN...WINDS LIKELY TO REMAIN LIGHT AND VARIABLE
UNDER 8 KTS THE REMAINDER OF THE MORNING...THEN INCREASE TO 12-16KTS
WITH GUSTS TO 25 KTS FROM THE SOUTH-SOUTHWEST BY NOON. SHOWER AND
THUNDERSTORM ACTIVITY WILL BE FAIRLY LIMITED THE REMAINDER OF THE
MORNING...BUT CANNOT BE COMPLETELY RULED OUT. CIGS OF 4-6K NEAR ANY
SHOWER ACTIVITY TONIGHT...OTHERWISE SCT-BKN CLOUDS AT 6-8K FEET.
CHANCES FOR SHRA/TSRA WILL INCREASE EARLY THIS AFTERNOON AND PEAK
BETWEEN 20Z-23Z. CIGS OF 3-5K FEET ARE EXPECTED WITH THIS ACTIVITY
ALONG WITH MOUNTAIN OBSCURATIONS. STORMS COULD BRING GUSTY WINDS IN
EXCESS OF 35 KTS THESE STORMS...AS WELL AS REDUCED VSBY DUE TO HEAVY
RAIN. SLIGHT CHANCES FOR SHRA/TSRA WILL CONTINUE THROUGH EARLY NEXT
WEEK...MAINLY IN THE MOUNTAINS SURROUNDING THE VALLEY AND IN THE
EASTERN CORRIDORS.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...A BAND OF SHOWERS AND SCATTERED THUNDERSTORMS DEVELOPED
THIS MORNING AND WILL SLOWLY PUSH EAST ACROSS MAINLY SOUTHERN NEVADA
TODAY AND INTO NORTHWEST ARIZONA LATE THIS AFTERNOON AND EVENING.
THE STRONGEST THUNDERSTORMS WILL BE FAVORED OVER
CLARK...NYE...LINCOLN AND MOHAVE COUNTIES THROUGH THIS AFTERNOON.
GUSTS EXCEEDING 35 KTS ARE POSSIBLE WITH THUNDERSTORMS. CIGS WILL
MAINLY BE 3K-6K FEET IN AND NEAR SHRA/TSRA OTHERWISE 6K-10K FEET.
VSBY MAY BE REDUCED TO MVFR OR LOWER AND MOUNTAIN OBSCURATIONS ARE
LIKELY IN AND NEAR ANY SHRA/TSRA. OUTSIDE OF TSRA EXPECT SOUTHWEST
WINDS TO INCREASE TO 10-20 KTS WITH GUSTS 20-30 KTS IN MOST
LOCATIONS BY THE AFTERNOON. CHANCES FOR SHRA/TSRA WILL CONTINUE
THROUGH EARLY NEXT WEEK...MAINLY FROM LAS VEGAS EAST. &&
.PREV DISCUSSION...
251 AM PDT SUN OCT 18 2015
.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT.
TODAY...CONVECTION HAS BEEN INCREASING OVER THE PAST THREE HOURS AS
EXPECTED ALONG A LINE FROM BARSTOW TO TONOPAH. THUS FAR...STORMS
HAVE BEEN SOMEWHAT ISOLATED AND INTENSE...BUT SHORT RANGE GUIDANCE
INDICATED THAT THE LINE SHOULD FILL IN SOMEWHAT THROUGH THE MORNING
HOURS. THIS CONVECTION HAS DEVELOPED IN RESPONSE TO THE INTERACTION
OF DIFFLUENT UPPER LEVEL FLOW AHEAD OF AN EJECTING SHORTWAVE AND
MODERATELY UNSTABLE CONDITIONS WITH ANOMALOUSLY HIGH MOISTURE
LEVELS. THIS LINE IS EXPECTED TO PUSH EAST ACROSS THE REGION TODAY.
GUIDANCE HAS SPED UP THE EASTWARD PROGRESSION OF THIS LINE...WITH
LAS VEGAS LIKELY UNDER THE GUN BETWEEN 15Z-21Z (8AM-2PM). BY MID TO
LATE MORNING MORE WIDESPREAD...DIURNALLY AIDED CONVECTION IS
EXPECTED TO BREAK OUT AHEAD OF THIS LINE ACROSS MOHAVE...EASTERN SAN
BERNARDINO AND EASTERN CLARK COUNTIES. PRECIPITABLE WATER VALUES OF
1.00-1.50" ARE ALREADY IN PLACE ACROSS THE REGION. THIS IS WELL
ABOVE RECORD LEVELS FOR THE MONTH (FOR REFERENCE...THE PREVIOUS
OCTOBER RECORD WAS 1.07" AND THE 90TH PERCENTILE FOR THE DATE IS
0.65"). STORM MOTION TODAY WILL TO THE NNE AT AROUND 20
MPH...HOWEVER CONDITIONS SHOULD BE FAVORABLE FOR TRAINING
STORMS...ESPECIALLY TO THE NORTH-NORTHEAST OF HIGHER TERRAIN
FEATURES. ALL OF THIS MEANS THE THE PRIMARY THREAT WITH STORMS TODAY
WILL BE FLASH FLOODING AND THE FLASH FLOOD WATCH WILL REMAIN IN
EFFECT THROUGH THIS EVENING. HAIL AND GUSTY WINDS WILL ALSO BE
POSSIBLE TODAY COURTESY OF 0-6KM SHEAR VALUES OF 25-40KTS...WHICH
MAY ALSO AID IN STORM ORGANIZATION. MUCH OF THIS ACTIVITY IS
EXPECTED TO PUSH EAST OF THE AREA OVERNIGHT...THOUGH LINGERING
CHANCES WILL REMAIN ACROSS AT LEAST LINCOLN AND MOHAVE COUNTIES.
MONDAY...ANOTHER SHORTWAVE IS EXPECTED TO HELP DIG TODAYS UPPER
LEVEL LOW FURTHER SOUTH...LEAVING AT LEAST THE EASTERN HALF OF THE
FORECAST AREA (FROM LAS VEGAS EAST) WITH CHANCES FOR ADDITIONAL
STORMS.
TUESDAY AND WEDNESDAY...MONDAY`S SHORTWAVE SHOULD ALLOW THE UPPER
LEVEL LOW TO WRAP UP AND BECOME CENTERED NEAR YUMA. THIS IS LIKELY
TO RESULT IN INCREASED NORTHERLY FLOW ACROSS THE REGION...AND GUSTY
NORTH WINDS ARE LIKELY IN FAVORED AREAS SUCH AS THE COLORADO RIVER
VALLEY. DESPITE THIS...MOISTURE WILL CONTINUE TO LINGER ACROSS THE
EASTERN PORTIONS OF THE FORECAST AREA AND CHANCE FOR STORMS WILL
CONTINUE...WITH THE BEST CHANCES OVER THE HIGHER TERRAIN OF
CLARK...MOHAVE...LINCOLN AND EASTERN SAN BERNARDINO COUNTIES.
.LONG TERM...THURSDAY THROUGH SATURDAY.
PATTERN SHOULD BECOME FAVORABLE FOR DRIER NORTHWEST FLOW...WHICH
SHOULD HELP BRING RELIEF FROM A PROLONGED PERIOD OF UNSETTLED AND
WET WEATHER. SHORTWAVES MOVING THROUGH THE FLOW COULD BRING ENHANCED
WINDS TO THE REGION AT TIMES. OTHERWISE EXPECT CALMER AND SLIGHTLY
WARMER CONDITIONS THAN THE FIRST HALF OF THE WEEK.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION MAY BE REQUIRED
TODAY. SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
&&
$$
UPDATE...ADAIR
AVIATION...GORELOW
PREV DISCUSSION...WOLCOTT
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
1253 AM PDT SUN OCT 18 2015
.SYNOPSIS...A BROAD LOW PRESSURE SYSTEM MOVING ACROSS CALIFORNIA AND
NEVADA TONIGHT AND SUNDAY WILL BRING INCREASING COVERAGE OF SHOWERS
AND SCATTERED THUNDERSTORMS TO MUCH OF THE REGION SUNDAY MORNING
THROUGH SUNDAY AFTERNOON. ADDITIONAL UPPER LEVEL DISTURBANCES WILL
CONTINUE TO PROVIDE UNSETTLED AND COOL CONDITIONS INTO THE MIDDLE OF
NEXT WEEK.
&&
.UPDATE...1250 AM...QUICK UPDATE TO INCREASE PRECIP CHANCES OVER
SOUTHERN SAN BERNARDINO AND MOHAVE COUNTIES (INCLUDING LAKE HAVASU)
WHERE A COUPLE ISOLATED STORMS HAVE DEVELOPED. THE REST OF THE
FORECAST REMAINS ON TRACK EARLY THIS MORNING. ISOLATED-SCATTERED
STORMS HAVE BEGUN TO DEVELOP AS EXPECTED ACROSS WESTERN SAN
BERNARDINO AND EASTERN INYO COUNTIES...TRACKING NORTHEAST. THESE
STORMS ARE BEING MONITORED CLOSELY FOR FLASH FLOODING.
&&
.PREV UPDATE...855 PM PDT SAT OCT 17 2015...MOST OF THE AREA IS FREE
OF CONVECTION AT THIS HOUR...HOWEVER SHORT RANGE GUIDANCE SUGGEST
THAT THIS WILL CHANGE OVER THE NEXT FEW HOURS. THE HRRR AND HRRRX
HAVE BEEN FAIRLY CONSISTENT SHOWING AN UPTICK IN ACTIVITY ALONG AND
WEST OF A LINE FROM BARSTOW TO TONOPAH BETWEEN 04Z AND 06Z THIS
EVENING. THIS WILL BE IN RESPONSE TO UPPER LEVEL FORCING
ENCOUNTERING AN UNSTABLE AIRMASS. EXPECT MUCH OF THIS ACTIVITY TO
CONGEAL INTO A NORTH-SOUTH BAND OF SHOWERS WITH EMBEDDED
THUNDERSTORMS BETWEEN 06Z AND 12Z AND SLOWLY PROGRESS EAST. BASED ON
MODEL CONSENSUS...BY 12Z THIS LINE SHOULD STRETCH FROM ROUGHLY BAKER
TO RACHEL. THROUGH SUNDAY THIS LINE WILL CONTINUE TO PUSH
EAST...GRADUALLY PIVOTING TO A SSW-NNE ORIENTATION. AS THIS OCCURS
THUNDERSTORM COVERAGE AND INTENSITY BOTH IN AND AHEAD OF THE BAND
(MOHAVE AND EASTERN CLARK COUNTIES) IS LIKELY TO INCREASE WITH THE
ADDITION OF DAYTIME HEATING. CURRENT GUIDANCE SUGGESTS THE MOST
LIKELY TIMING FOR THIS BAND TO CROSS THE LAS VEGAS VALLEY WOULD BE
FROM 19Z-23Z (12PM-4PM). FORECAST HAS BEEN TWEAKED TO ACCOUNT FOR
THE LATEST MODEL ANALYSIS THROUGH SUNDAY. CURRENT FLASH FLOOD WATCH
PLACEMENT AND TIMING APPEARS TO BE GOOD AND NO CHANGES TO THAT
PRODUCT ARE EXPECTED AT THIS TIME. &&
.AVIATION...FOR MCCARRAN...WINDS LIKELY TO REMAIN LIGHT AND VARIABLE
UNDER 8 KTS OVERNIGHT...THEN INCREASE TO 12-16KTS WITH GUSTS TO 25
KTS FROM THE SOUTH-SOUTHWEST AFTER 18Z. SHOWER AND THUNDERSTORM
ACTIVITY WILL BE FAIRLY LIMITED THE REMAINDER OF THE NIGHT...BUT
CANNOT BE COMPLETELY RULED OUT. CIGS OF 4-6K NEAR ANY SHOWER
ACTIVITY TONIGHT...OTHERWISE SCT-BKN CLOUDS AT 6-8K FEET. CHANCES
FOR SHRA/TSRA WILL INCREASE LATE SUNDAY MORNING AND PEAK BETWEEN 19Z-
23Z. CIGS OF 3-5K FEET ARE EXPECTED WITH THIS ACTIVITY ALONG WITH
MOUNTAIN OBSCURATIONS. STORMS COULD BRING GUSTY WINDS IN EXCESS OF
35 KTS THESE STORMS...AS WELL AS REDUCED VSBY. SLIGHT CHANCES FOR
SHRA/TSRA WILL CONTINUE THROUGH EARLY NEXT WEEK.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...ISOLATED SHRA/TSRA ARE POSSIBLE THROUGH TONIGHT.
SHOWERS AND THUNDERSTORMS WILL BE FAVORED OVER CLARK...NYE...LINCOLN
AND MOHAVE COUNTIES ON SUNDAY. GUSTS EXCEEDING 35 KTS ARE POSSIBLE
WITH THUNDERSTORMS. CIGS WILL MAINLY BE 4K-6K FEET IN AND NEAR
SHRA/TSRA OTHERWISE 8K-12K FEET. VSBY MAY BE REDUCED TO MVFR OR
LOWER AND MOUNTAIN OBSCURATIONS ARE LIKELY IN AND NEAR ANY
SHRA/TSRA. OUTSIDE OF TSRA EXPECT SOUTHWEST WINDS TO INCREASE TO 10-
20 KTS WITH GUSTS 20-30 KTS IN MOST LOCATIONS BY THE AFTERNOON.
CHANCES FOR SHRA/TSRA WILL CONTINUE THROUGH EARLY NEXT WEEK...MAINLY
FROM LAS VEGAS EAST.
&&
.SHORT TERM...TONIGHT THROUGH MONDAY NIGHT.
IT LOOKS LIKE THE INGREDIENTS ARE COMING TOGETHER FOR AN AN ACTIVE
WEATHER DAY SUNDAY ACROSS SOUTHERN SOUTHERN NEVADA AND SURROUNDING
AREAS OF NORTHWEST ARIZONA AND SOUTHEAST CALIFORNIA. ANOMALOUSLY
HIGH MOISTURE CONTENT WILL REMAIN IN PLACE ACROSS THE REGION WITH
PWAT VALUES OF 1.0-1.3 INCHES AND SURFACE DEWPOINTS GENERALLY IN THE
60S. THE LIFTING MECHANISM NEEDED TO TURN THIS MOISTURE INTO SHOWERS
AND THUNDERSTORMS IS COMING IN THE FORM OF A VIGOROUS LOW PRESSURE
SYSTEM CURRENTLY OFF THE NORTHERN CALIFORNIA COAST. THE CENTER OF
THIS BROAD SYSTEM IS FORECAST TO MOVE INLAND OVER NORTHERN
CALIFORNIA SUNDAY BUT A VORT MAX AND 50-60 KNOT JET ROUNDING THE
BASE OF THE LOW AND EJECTING UP ACROSS SOUTHERN NEVADA WILL PROVIDE
PLENTY OF DYNAMIC FORCING COMBINED WITH SOME DESTABILIZATION DUE TO
COOLER AIR ALOFT ASSOCIATED WITH THE SYSTEM. FORECAST SOUNDINGS LATE
SUNDAY MORNING INDICATE CONSIDERABLE INSTABILITY WITH CAPE VALUES
AROUND 1500-1800 J/KG...LIFTED INDICES AROUND -5 AND CONSIDERABLE
SPEED SHEAR WITH THE STRENGTHENING SOUTH-SOUTHWEST FLOW. THIS SHOULD
LEAD TO FAST MOVING FAIRLY ORGANIZED THUNDERSTORMS AND THE POTENTIAL
FOR TRAINING CELLS WHICH WILL ELEVATE THE FLASH FLOOD THREAT. THIS
COULD LEAD TO MORE THAN JUST LOCALIZED FLASH FLOOD POTENTIAL SUNDAY
AND JUSTIFIES THE FLASH FLOOD WATCH THAT IS ALREADY IN EFFECT UNTIL
SUNDAY EVENING. THE BEST WINDOW FOR THESE THINGS TO COME TOGETHER
LOOKS TO BE BETWEEN 12Z AND 18Z THEN CONTINUING THROUGH SUNDAY
AFTERNOON...SO WE SHOULD SEE AN EARLY START TO STORM DEVELOPMENT.
AS THE VORT MAX CONTINUES LIFTING UP THROUGH UTAH SUNDAY EVENING...
DRY SOUTHWEST FLOW ALOFT SHOULD GRADUALLY DECREASE MOISTURE CONTENT
BUT ISOLATED TO SCATTERED SHOWERS WILL STILL BE POSSIBLE OVER
SOUTHERN NEVADA AND NORTHWEST ARIZONA SUNDAY NIGHT INTO MONDAY
MORNING. ADDITIONAL ENERGY IS FORECAST TO DIVE DOWN THE WEST COAST
MONDAY AND DRAG THE TROUGH SOUTHWARD WHILE SPINNING IT UP INTO A
CLOSED LOW CENTERED NEAR YUMA ARIZONA BY TUESDAY MORNING. THIS WILL
PLACE MOHAVE COUNTY NEAR THE NORTHEAST QUADRANT OF THE LOW LEADING
TO A CONTINUED CHANCE OF SHOWERS AND THUNDERSTORMS. IN
ADDITION...THIS WILL KEEP COOL TEMPERATURES IN PLACE ACROSS THE
REGION WITH HIGHS 3-5 DEGREES BELOW NORMAL.
.LONG TERM...TUESDAY THROUGH SATURDAY.
YET ANOTHER SHORTWAVE TROUGH WILL BE CENTERED DIRECTLY OVER OUR AREA
TO START THE LONG TERM PERIOD. THIS SHORTWAVE WILL SPIN UP INTO A
CLOSED LOW CENTERED OVER THE LOWER COLORADO RIVER VALLEY ALONG THE
CALIFORNIA/ARIZONA BORDER TUESDAY NIGHT AND BE NEARLY STATIONARY
THROUGH WEDNESDAY. THIS WILL KEEP COOLER CONDITIONS AROUND THROUGH
AT LEAST MID WEEK ALONG WITH A CHANCE OF SHOWERS CONTINUING OVER
PORTIONS OF LINCOLN, CLARK, SAN BERNARDINO, AND MOHAVE COUNTIES.
GIVEN THE FAIRLY GOOD MODEL AGREEMENT, DID EXPAND PRECIP CHANCES A
LITTLE FARTHER WEST AND INCREASED POPS A BIT. THE LOW WILL THEN EDGE
INTO CENTRAL ARIZONA THURSDAY AND FINALLY DEPART THURSDAY NIGHT INTO
FRIDAY. COULD STILL SEE SOME SHOWERS LINGERING ACROSS NORTHWEST
ARIZONA (PERHAPS SLIGHTLY FARTHER WEST) THURSDAY. HAVE GONE WITH AN
AREA-WIDE DRY FORECAST FRIDAY AND FRIDAY NIGHT WITH MORE OF A QUASI-
ZONAL FLOW ALOFT SETTING IN. THE 00Z MODELS SUGGEST DRY CONDITIONS
MAY CONTINUE INTO SATURDAY BUT RUN-TO-RUN MODEL TRENDS HAVE NOT BEEN
VERY GOOD. THERE ARE SIGNS THAT ANOTHER TROUGH MAY APPROACH OR SWING
INTO THE SOUTHWEST AT SOME POINT NEXT WEEKEND. STILL A LOT OF
UNCERTAINTY WITH TIMING AND JUST HOW DEEP/STRONG IT MAY BE. WILL
KEEP AN EYE ON MODEL TRENDS AND ADJUST AS NECESSARY.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION MAY BE REQUIRED
THIS WEEKEND. SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT
WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
&&
$$
UPDATE/AVIATION...WOLCOTT
SHORT TERM........ADAIR
LONG TERM.........PADDOCK
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1003 PM EDT MON OCT 19 2015
.SYNOPSIS...
HIGH PRESSURE OVER THE CAROLINAS WILL SLIP OFFSHORE WEDNESDAY AND
THURSDAY WITH WARMING TEMPERATURES EXPECTED. A BACKDOOR COLD
FRONT WILL MOVE ACROSS THE AREA FRIDAY. ANOTHER COLD FRONT MAY
MOVE ACROSS THE AREA ON MONDAY...BRINGING A SMALL CHANCE FOR
SHOWERS.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 1000 PM...BESIDES A FEW TWEAKS TO HOURLY TEMPERATURE CURVES
AND DEWPOINTS BASED ON CURRENT OBS...NO CHANGES HAVE BEEN MADE TO
THE FORECAST WITH THIS LATE EVENING UPDATE. DISCUSSION FROM 730
PM FOLLOWS...
CANADIAN HIGH PRESSURE HAS SETTLED OVER THE COASTAL PLAIN THIS
EVENING EXTENDING FROM NORFOLK VA TO AUGUSTA GA. THIS HIGH SHOULD
MOVE VERY LITTLE THROUGH THE NIGHT. THE BROAD AREA OF WEAK
PRESSURE GRADIENT WITHIN THE HIGH WILL SUPPORT CALM WINDS AND
EXCELLENT RADIATIONAL COOLING TONIGHT. FORECAST LOWS ARE AT OR
BELOW THE LOWER END OF THE MOS GUIDANCE ENVELOPE AT ALL SITES. OUR
LOCAL RADIATIONAL COOLING TOOL SHOWS THE "POCOSIN" COLD SPOTS
SHOULD RUN A GOOD 8 DEGREES COLDER THAN NEARBY AREAS TONIGHT WITH
LOWS AROUND 30 POSSIBLE IN THE GREEN SWAMP...BLADEN LAKES STATE
FOREST...AND THE ANGOLA BAY GAMELAND ON THE PENDER-DUPLIN COUNTY
LINE.
IN THE UPPER LEVELS A LOW-AMPLITUDE LONGWAVE RIDGE COVERS MUCH OF
THE CENTRAL AND EASTERN PORTIONS OF THE NATION. A SUBTLE 500 MB
SHORTWAVE IS ACTUALLY TRAVERSING THE CAROLINAS NOW BUT WILL HAVE
NO IMPACT ON SENSIBLE WEATHER AT THE SURFACE. AS THE 850 MB HIGH
SCOOTS OFF THE COAST LATE TONIGHT WINDS AT THAT LEVEL SHOULD TURN
EASTERLY. THIS WILL BEGIN TO ADVECT ATLANTIC MOISTURE BACK TOWARD
THE COAST...BUT THIS PROCESS APPEARS IT WILL PROCEED QUITE SLOWLY
AND I HAVE DELAYED ANY INCREASE IN CLOUD COVER UNTIL AFTER
DAYBREAK TUESDAY.
NO CHANGES HAVE BEEN MADE TO THE FROST ADVISORY ALREADY ISSUED FOR
MUCH OF THE EASTERN CAROLINAS INLAND FROM THE COAST. DEWPOINTS
HAVE RISEN INTO THE MID TO UPPER 30S AT MANY SITES SINCE SUNSET.
WHILE THIS IS A PAPER-THIN LAYER OF MOISTURE LIKELY ONLY EXTENDING
ONE OR TWO HUNDRED FEET VERTICALLY...IT MAY HAVE THE INTERESTING
EFFECT OF CREATING DEW ON ELEVATED OBJECTS LATE THIS EVENING
WHICH WILL THEN FREEZE LATE TONIGHT AS AIR TEMPERATURES FALL TO
33-36. YOU MIGHT WANT TO PLAN ON SPENDING A FEW EXTRA MINUTES TO
SCRAPE THROUGH THIS LAYER OF ICE ON YOUR WINDSHIELD IN THE
MORNING.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 300 PM MONDAY...TEMPS WILL MODERATE CONSIDERABLY THROUGH
THE PERIOD. THE CENTER OF THE CHILLY AIRMASS WILL SHIFT OFFSHORE
DURING TUE. THE HIGH WILL RIDGE BACK ACROSS THE CAROLINAS...BUT
WITH THE AXIS N OF THE FORECAST AREA...WINDS WILL BECOME MORE
EASTERLY WITH TIME. THE RESULT WILL BE HIGHER TEMPS AND HIGHER
MOISTURE CONTENT WHICH WILL INCREASE DAYTIME RELATIVE HUMIDITY
VALUES. A WEAK COASTAL TROUGH MAY LINGER OFFSHORE OF THE CAROLINAS
THROUGH THE PERIOD. WILL KEEP THE ASSOCIATED PRECIPITATION
OFFSHORE FOR NOW...BUT SOME OF THE MODELS ARE HINTING AT SOME
SPOTTY AND LIGHT COASTAL SHOWERS DURING THE PERIOD. A DEEP
EASTERLY FLOW WILL ENVELOP THE AREA WHICH WILL ALLOW PRECIPITABLE
WATER VALUES TO RISE TO NEAR AN INCH ALONG THE COAST TUE AND
THROUGHOUT ON WED. EXPECT CLEAR SKIES WILL BECOME PARTLY CLOUDY AT
THE COAST TUE AND THEN THROUGHOUT ON WED.
HIGHS TUE WILL BE NEAR 70...MID 70S ON WED. LOWS TUE NIGHT WILL BE
IN THE MID AND UPPER 40S...LOWER 50S AT THE COAST. LOWS WED NIGHT
WILL BE IN THE LOWER TO MID 50S...UPPER 50S TO NEAR 60 ALONG THE
COAST.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 300 PM MONDAY...MID LEVEL RIDGING WILL PERSIST ACROSS THE
GULF OF MEXICO THURSDAY THROUGH SATURDAY AS LOW PRESSURE CONTINUES
TO WOBBLE ACROSS THE SOUTHWEST. THE BRIEF EXTENSION OF THE RIDGE
INTO THE GREAT LAKES AREA PUSHES A BACKDOOR FRONT ACROSS THE AREA
FRIDAY. THE DRY FRONT WILL PUSH BACK TEMPERATURES FOR SATURDAY.
THE REGION WILL SEE A RATHER QUICK REBOUND SUNDAY AND MONDAY AS
THE GULF RIDGE GETS WORKED OVER SUFFICIENTLY TO ALLOW THE NOW OPEN
WAVE...PREVIOUS SOUTHWEST SYSTEM TO MOVE ACROSS QUICKLY. THE
ATTENDANT FRONT SHOULD ARRIVE SOMETIME MONDAY. MOISTURE IS LIMITED
WITH THE FRONT BUT WILL MAINTAIN A SLIGHT CHANCE POP. MEDIUM RANGE
GUIDANCE HINTING AT A BETTER CHANCE OF RAIN MAYBE TOWARD THE
MIDDLE OF NEXT WEEK. OVERALL TEMPERATURE TRENDS REMAIN INTACT WITH
WARM READINGS THURSDAY FALLING BACK BRIEFLY SATURDAY THEN THE
AFOREMENTIONED RECOVERY.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
AS OF 00Z...HIGH PRESSURE WILL REMAIN IN CONTROL THROUGH THE FORECAST
PERIOD. EXCELLENT RADIATIONAL COOLING CONDITIONS TONIGHT...WITH
DECOUPLING EXPECTED AT ALL SITES WITH CALM OR NEAR CALM WINDS. MOISTURE
PROFILES DO NOT SUPPORT FOG...HOWEVER THERE COULD BE SOME SHALLOW
GROUND FOG IN LOW SPOTS. A WEAK TROUGH OFFSHORE COULD PRODUCE SOME
CU/STRATA CU AFTER DAYBREAK ALONG THE COAST. LIGHT NORTHEAST FLOW
IS EXPECTED ON TUESDAY.
EXTENDED OUTLOOK...THERE IS A SMALL CHANCE WED/THU THAT
A WEAK TROUGH WILL SPREAD LIGHT SHOWERS ONSHORE AND AFFECT THE
COASTAL TERMINALS. OTHERWISE HIGH PRESSURE AND VFR CONDITIONS
THROUGH SATURDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 PM MONDAY...WIND DIRECTIONS HAVE BACKED AROUND TO THE
NORTH AT THE BEACHES...LIKELY DUE TO A LANDBREEZE DEVELOPING AS
ONSHORE-OFFSHORE AIR TEMPERATURE DIFFERENCES GROW. NO OTHER
SIGNIFICANT ADJUSTMENTS HAVE BEEN MADE TO THE FORECAST OVERNIGHT.
DISCUSSION FROM 730 PM FOLLOWS...
1031 MB CANADIAN HIGH PRESSURE EXTENDS FROM THE HAMPTON ROADS
AREA SOUTHWESTWARD INTO CENTRAL SOUTH CAROLINA. THIS WILL MAINTAIN
A NORTH-NORTHEASTERLY WIND ACROSS THE WATERS TONIGHT. LATEST
MODELS HAVE SOME DIFFERENCES WITH FORECAST WIND SPEEDS...ALTHOUGH
MOST ARE TIGHTLY CLUSTERED WITH WINDS IN THE 12-16 KNOT RANGE
OVERNIGHT. THE 21Z RUC WAS NOT USED SINCE ITS OVERNIGHT WINDS WERE
MUCH LIGHTER COMPARED TO OTHER MODELS. BUOY REPORTS AT 6 PM SHOWED
SEAS HAVE DECAYED AWAY TO 2-4 FEET INSIDE 20 MILES OF SHORE...WITH
ANY 4-FOOT SEAS LIKELY CONFINED TO AREAS NEAR FRYING PAN SHOALS
AND CAPE ROMAIN. SPECTRAL WAVE DATA FROM THE FRYING PAN SHOALS
BUOY SHOWS THE BULK OF THE WAVE ENERGY IS AROUND 6 SECONDS PERIOD.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 PM MONDAY...HIGH PRESSURE WILL MOVE OFFSHORE DURING TUE
AND THEN RIDGE BACK ACROSS THE AREA THROUGH THE REMAINDER OF THE
PERIOD. A WEAK COASTAL TROUGH MAY LINGER NEAR THE WATERS THROUGH THE
PERIOD. THIS SCENARIO WILL RESULT IN NE WINDS TUE VEERING TO A MORE
ENE TO E DIRECTION TUE NIGHT WITH A SIMILAR DIRECTION THROUGH THE
REMAINDER OF THE PERIOD. WIND SPEEDS WILL BE 10 TO 15 KT OR LESS.
SEAS WILL BE 2 TO 3 FT...WITH SOME 4 FT SEAS ACROSS PORTIONS OF THE
OUTERMOST WATERS.
LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 300 PM MONDAY...ESSENTIALLY LIGHT AND VARIABLE WIND FIELDS
THURSDAY AS WEAKENING HIGH PRESSURE SITS OVERHEAD. A BACKDOOR FRONT
MOVES ACROSS FRIDAY WITH ANOTHER PERIOD OF WINDS FROM THE NORTH
DEVELOPING. BY FRIDAY AFTERNOON WE SHOULD SEE A NORTHEAST FLOW OF 10-
15 KNOTS. THIS SHOULD CONTINUE THROUGH SUNDAY MORNING. THERE COULD
BE A FEW HOURS OF 15-20 KNOTS FRIDAY NIGHT DUE TO AN EMBEDDED SURGE.
SEAS ARE MOSTLY 2-4 FEET WITH A FEW FIVE FOOTERS DEVELOPING WITH THE
SURGE.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...FROST ADVISORY FROM 4 AM TO 9 AM EDT TUESDAY FOR SCZ017-023-
024-032-033-039-053.
NC...FROST ADVISORY FROM 4 AM TO 9 AM EDT TUESDAY FOR NCZ087-096-
099-105-109.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...TRA
SHORT TERM...RJD
LONG TERM...SHK
AVIATION...DL
MARINE...
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
720 PM EDT MON OCT 19 2015
.SYNOPSIS...
HIGH PRESSURE OVER THE CAROLINAS WILL SLIP OFFSHORE WEDNESDAY AND
THURSDAY WITH WARMING TEMPERATURES EXPECTED. A BACKDOOR COLD
FRONT WILL MOVE ACROSS THE AREA FRIDAY. ANOTHER COLD FRONT MAY
MOVE ACROSS THE AREA ON MONDAY...BRINGING A SMALL CHANCE FOR
SHOWERS.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 730 PM...CANADIAN HIGH PRESSURE HAS SETTLED OVER THE COASTAL
PLAIN THIS EVENING EXTENDING FROM NORFOLK VA TO AUGUSTA GA. THIS
HIGH SHOULD MOVE VERY LITTLE THROUGH THE NIGHT. THE BROAD AREA OF
WEAK PRESSURE GRADIENT WITHIN THE HIGH WILL SUPPORT CALM WINDS
AND EXCELLENT RADIATIONAL COOLING TONIGHT. FORECAST LOWS ARE AT
OR BELOW THE LOWER END OF THE MOS GUIDANCE ENVELOPE AT ALL SITES.
OUR LOCAL RADIATIONAL COOLING TOOL SHOWS THE "POCOSIN" COLD SPOTS
SHOULD RUN A GOOD 8 DEGREES COLDER THAN NEARBY AREAS TONIGHT WITH
LOWS AROUND 30 POSSIBLE IN THE GREEN SWAMP...BLADEN LAKES STATE
FOREST...AND THE ANGOLA BAY GAMELAND ON THE PENDER-DUPLIN COUNTY
LINE.
IN THE UPPER LEVELS A LOW-AMPLITUDE LONGWAVE RIDGE COVERS MUCH OF
THE CENTRAL AND EASTERN PORTIONS OF THE NATION. A SUBTLE 500 MB
SHORTWAVE IS ACTUALLY TRAVERSING THE CAROLINAS NOW BUT WILL HAVE
NO IMPACT ON SENSIBLE WEATHER AT THE SURFACE. AS THE 850 MB HIGH
SCOOTS OFF THE COAST LATE TONIGHT WINDS AT THAT LEVEL SHOULD TURN
EASTERLY. THIS WILL BEGIN TO ADVECT ATLANTIC MOISTURE BACK TOWARD
THE COAST...BUT THIS PROCESS APPEARS IT WILL PROCEED QUITE SLOWLY
AND I HAVE DELAYED ANY INCREASE IN CLOUD COVER UNTIL AFTER
DAYBREAK TUESDAY.
NO CHANGES HAVE BEEN MADE TO THE FROST ADVISORY ALREADY ISSUED FOR
MUCH OF THE EASTERN CAROLINAS INLAND FROM THE COAST. DEWPOINTS
HAVE RISEN INTO THE MID TO UPPER 30S AT MANY SITES SINCE SUNSET.
WHILE THIS IS A PAPER-THIN LAYER OF MOISTURE LIKELY ONLY EXTENDING
ONE OR TWO HUNDRED FEET VERTICALLY...IT MAY HAVE THE INTERESTING
EFFECT OF CREATING DEW ON ELEVATED OBJECTS LATE THIS EVENING
WHICH WILL THEN FREEZE LATE TONIGHT AS AIR TEMPERATURES FALL TO
33-36. YOU MIGHT WANT TO PLAN ON SPENDING A FEW EXTRA MINUTES TO
SCRAPE THROUGH THIS LAYER OF ICE ON YOUR WINDSHIELD IN THE
MORNING.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 300 PM MONDAY...TEMPS WILL MODERATE CONSIDERABLY THROUGH
THE PERIOD. THE CENTER OF THE CHILLY AIRMASS WILL SHIFT OFFSHORE
DURING TUE. THE HIGH WILL RIDGE BACK ACROSS THE CAROLINAS...BUT
WITH THE AXIS N OF THE FORECAST AREA...WINDS WILL BECOME MORE
EASTERLY WITH TIME. THE RESULT WILL BE HIGHER TEMPS AND HIGHER
MOISTURE CONTENT WHICH WILL INCREASE DAYTIME RELATIVE HUMIDITY
VALUES. A WEAK COASTAL TROUGH MAY LINGER OFFSHORE OF THE CAROLINAS
THROUGH THE PERIOD. WILL KEEP THE ASSOCIATED PRECIPITATION
OFFSHORE FOR NOW...BUT SOME OF THE MODELS ARE HINTING AT SOME
SPOTTY AND LIGHT COASTAL SHOWERS DURING THE PERIOD. A DEEP
EASTERLY FLOW WILL ENVELOP THE AREA WHICH WILL ALLOW PRECIPITABLE
WATER VALUES TO RISE TO NEAR AN INCH ALONG THE COAST TUE AND
THROUGHOUT ON WED. EXPECT CLEAR SKIES WILL BECOME PARTLY CLOUDY AT
THE COAST TUE AND THEN THROUGHOUT ON WED.
HIGHS TUE WILL BE NEAR 70...MID 70S ON WED. LOWS TUE NIGHT WILL BE
IN THE MID AND UPPER 40S...LOWER 50S AT THE COAST. LOWS WED NIGHT
WILL BE IN THE LOWER TO MID 50S...UPPER 50S TO NEAR 60 ALONG THE
COAST.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 300 PM MONDAY...MID LEVEL RIDGING WILL PERSIST ACROSS THE
GULF OF MEXICO THURSDAY THROUGH SATURDAY AS LOW PRESSURE CONTINUES
TO WOBBLE ACROSS THE SOUTHWEST. THE BRIEF EXTENSION OF THE RIDGE
INTO THE GREAT LAKES AREA PUSHES A BACKDOOR FRONT ACROSS THE AREA
FRIDAY. THE DRY FRONT WILL PUSH BACK TEMPERATURES FOR SATURDAY.
THE REGION WILL SEE A RATHER QUICK REBOUND SUNDAY AND MONDAY AS
THE GULF RIDGE GETS WORKED OVER SUFFICIENTLY TO ALLOW THE NOW OPEN
WAVE...PREVIOUS SOUTHWEST SYSTEM TO MOVE ACROSS QUICKLY. THE
ATTENDANT FRONT SHOULD ARRIVE SOMETIME MONDAY. MOISTURE IS LIMITED
WITH THE FRONT BUT WILL MAINTAIN A SLIGHT CHANCE POP. MEDIUM RANGE
GUIDANCE HINTING AT A BETTER CHANCE OF RAIN MAYBE TOWARD THE
MIDDLE OF NEXT WEEK. OVERALL TEMPERATURE TRENDS REMAIN INTACT WITH
WARM READINGS THURSDAY FALLING BACK BRIEFLY SATURDAY THEN THE
AFOREMENTIONED RECOVERY.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
AS OF 00Z...HIGH PRESSURE WILL REMAIN IN CONTROL THROUGH THE FORECAST
PERIOD. EXCELLENT RADIATIONAL COOLING CONDITIONS TONIGHT...WITH
DECOUPLING EXPECTED AT ALL SITES WITH CALM OR NEAR CALM WINDS. MOISTURE
PROFILES DO NOT SUPPORT FOG...HOWEVER THERE COULD BE SOME SHALLOW
GROUND FOG IN LOW SPOTS. A WEAK TROUGH OFFSHORE COULD PRODUCE SOME
CU/STRATA CU AFTER DAYBREAK ALONG THE COAST. LIGHT NORTHEAST FLOW
IS EXPECTED ON TUESDAY.
EXTENDED OUTLOOK...THERE IS A SMALL CHANCE WED/THU THAT
A WEAK TROUGH WILL SPREAD LIGHT SHOWERS ONSHORE AND AFFECT THE
COASTAL TERMINALS. OTHERWISE HIGH PRESSURE AND VFR CONDITIONS
THROUGH SATURDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 730 PM MONDAY...1031 MB CANADIAN HIGH PRESSURE EXTENDS FROM
THE HAMPTON ROADS AREA SOUTHWESTWARD INTO CENTRAL SOUTH CAROLINA.
THIS WILL MAINTAIN A NORTH-NORTHEASTERLY WIND ACROSS THE WATERS
TONIGHT. LATEST MODELS HAVE SOME DIFFERENCES WITH FORECAST WIND
SPEEDS...ALTHOUGH MOST ARE TIGHTLY CLUSTERED WITH WINDS IN THE
12-16 KNOT RANGE OVERNIGHT. THE 21Z RUC WAS NOT USED SINCE ITS
OVERNIGHT WINDS WERE MUCH LIGHTER COMPARED TO OTHER MODELS. BUOY
REPORTS AT 6 PM SHOWED SEAS HAVE DECAYED AWAY TO 2-4 FEET INSIDE
20 MILES OF SHORE...WITH ANY 4-FOOT SEAS LIKELY CONFINED TO AREAS
NEAR FRYING PAN SHOALS AND CAPE ROMAIN. SPECTRAL WAVE DATA FROM
THE FRYING PAN SHOALS BUOY SHOWS THE BULK OF THE WAVE ENERGY IS
AROUND 6 SECONDS PERIOD.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 PM MONDAY...HIGH PRESSURE WILL MOVE OFFSHORE DURING TUE
AND THEN RIDGE BACK ACROSS THE AREA THROUGH THE REMAINDER OF THE
PERIOD. A WEAK COASTAL TROUGH MAY LINGER NEAR THE WATERS THROUGH THE
PERIOD. THIS SCENARIO WILL RESULT IN NE WINDS TUE VEERING TO A MORE
ENE TO E DIRECTION TUE NIGHT WITH A SIMILAR DIRECTION THROUGH THE
REMAINDER OF THE PERIOD. WIND SPEEDS WILL BE 10 TO 15 KT OR LESS.
SEAS WILL BE 2 TO 3 FT...WITH SOME 4 FT SEAS ACROSS PORTIONS OF THE
OUTERMOST WATERS.
LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 300 PM MONDAY...ESSENTIALLY LIGHT AND VARIABLE WIND FIELDS
THURSDAY AS WEAKENING HIGH PRESSURE SITS OVERHEAD. A BACKDOOR FRONT
MOVES ACROSS FRIDAY WITH ANOTHER PERIOD OF WINDS FROM THE NORTH
DEVELOPING. BY FRIDAY AFTERNOON WE SHOULD SEE A NORTHEAST FLOW OF 10-
15 KNOTS. THIS SHOULD CONTINUE THROUGH SUNDAY MORNING. THERE COULD
BE A FEW HOURS OF 15-20 KNOTS FRIDAY NIGHT DUE TO AN EMBEDDED SURGE.
SEAS ARE MOSTLY 2-4 FEET WITH A FEW FIVE FOOTERS DEVELOPING WITH THE
SURGE.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...FROST ADVISORY FROM 4 AM TO 9 AM EDT TUESDAY FOR SCZ017-023-
024-032-033-039-053.
NC...FROST ADVISORY FROM 4 AM TO 9 AM EDT TUESDAY FOR NCZ087-096-
099-105-109.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...TRA
SHORT TERM...RJD
LONG TERM...SHK
AVIATION...DL
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1215 AM EDT SUN OCT 18 2015
.SYNOPSIS...
A STRONG BUT DRY COLD FRONT WILL MOVE THROUGH TONIGHT. HIGH
PRESSURE WILL BUILD OVER THE AREA THIS WEEKEND THROUGH MUCH OF
NEXT WEEK. THE NEXT FRONTAL SYSTEM WILL APPROACH THE REGION LATE
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 1215 AM SUNDAY...APPEARS THAT THE DRY COLD FRONT HAS MOVED
THROUGH THE AREA AS OBSERVATIONS INDICATE THAT A SURGE OF COLD AIR
WAS OCCURRING OVER THE AREA LATE TONIGHT. POST FRONTAL DRY/COLD
ADVECTION AND LOW LEVEL MIXING WILL PRECLUDE ANY FOG DEVELOPMENT
OVERNIGHT. A WIDE RANGE OF LOWS EXPECTED...WITH UPR 30S INLAND TO
LOW 50S OBX...WHERE WIND ADVECTING OVER THE RELATIVELY WARM SOUND
WATERS WILL KEEP TEMPS UP HERE.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
AS OF 330 PM SAT...DEEP/COLD TROUGH AXIS PROGGED TO MOVE ACROSS
EASTERN CONUS ON SUNDAY WITH SFC HIGH PRES BUILDING INTO THE OHIO
VALLEY. LOW LEVEL THICKNESS VALS ON PAR WITH MOS GUID FORECASTING
CHILLY MAX TEMPS IN THE UPR 50S TO NEAR 60...COOLEST NORTH.
CONTINUED CAA AND NORTH WINDS WILL MAKE IT FEEL QUITE BRISK
DESPITE FULL SUNSHINE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
AS OF 330 PM SAT...MINOR ADJUSTMENTS TO TEMPS DURING PERIOD.
MODELS REMAIN IN GOOD AGREEMENT THAT RIDGING SFC AND ALOFT WILL
CONTINUE THROUGH MID WEEK...FOLLOWED BY ANOTHER DRY COLD FRONTAL
PASSAGE FRIDAY.
MAIN SIGNIFICANT WX THREAT DURING PERIOD WILL BE PSBL FROST SUN
NIGHT AND AGAIN MON NIGHT. MODEL GDNC CONTINUES TO INDICATE
COLDEST TEMPS SUN NIGHT WITH LOWS 33-36 DEGS FOR NORMALLY COLDER
AREAS ALONG AND W OF HWY 17. COULD EVEN SEE SOME 32 DEG READINGS
IN ISOLATED AREAS BUT NOT EXPECTED TO BE WDSPRD ENOUGH TO WARRANT
FREEZE WATCH...BUT FROST ADVSY LIKELY TO BE ISSUED WITH NEXT FULL
FCST PACKAGE AROUND 4 AM SUNDAY. GOOD RADIATIONAL COOLING
CONDITIONS LIKELY AGAIN MON NIGHT WITH SFC HIGH CENTER OVER AREA
RESULTING IN LIGHT WINDS ALL THE WAY TO COAST. MOS GDNC INDICATING
LOWS MID TO UPR 30S FOR MOST INLAND AREAS...AND COULD SEE SCT
FROST THREAT EVEN CLOSER TO COAST THAN ON SUN NIGHT.
TEMPS WILL GRADUALLY MODERATE TUE-THU WITH RIDGING ALOFT WHILE SFC
HIGH EXTENDS OVER AREA FROM OFFSHORE. LOWS WILL BE IN 40S AND 50S
WITH HIGHS IN THE 70S.
FRIDAY TO SATURDAY...12Z GFS AND ECMWF HAVE COME INTO BETTER
AGREEMENT WITH ANOTHER DRY COLD FRONT MOVING THROUGH EARLY FRIDAY
FOLLOWED BY HIGH PRES RIDING IN FROM N FRI NIGHT AND SAT. TEMPS
WILL DROP BACK INTO 40S FRI NIGHT WITH HIGHS IN 60S FOR SAT.
&&
.AVIATION /04Z SUNDAY THROUGH THURSDAY/...
SHORT TERM /THROUGH SUNDAY NIGHT/...
AS OF 1215 AM SUNDAY...HIGH CONFIDENCE IN VFR CONDITIONS THROUGH
THE PERIOD AS HIGH PRESSURE BUILDS OVER THE REGION FROM THE NORTH.
DRY ADVECTION FOLLOWING THE PASSAGE OF A DRY COLD FRONT AND AMPLE
LOW LEVEL MIXING WILL INHIBIT LOW CLOUD AND FOG FORMATION
OVERNIGHT. KMHX 88D VWP SHOWS 40 KNOTS AT 1 KFT SO WILL KEEP NON
CONVECTIVE LLWS AT ALL TERMINALS. SHORT TERM MODELS SHOW WINDS
DECREASING AFTER ABOUT 09Z SO WILL CARRY LLWS WORDING UNTIL THEN.
LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 330 PM SAT...HIGH CONFIDENCE OF VFR CONDITIONS WILL
CONTINUE THROUGH THIS PERIOD AS HIGH PRESSURE DOMINATES THE
REGION.
&&
.MARINE...
SHORT TERM /THROUGH SUNDAY/...
AS OF 1215 AM SUNDAY...STRONG COLD AIR ADVECTION OVERNIGHT WILL
PRODUCE NORTHERLY FLOW TO 25 KT OVER MOST OF THE MARINE ZONES
OVERNIGHT INTO SUNDAY SO WILL CONTINUE CURRENT SCA HEADLINES. WINDS
WILL PEAK LATE TONIGHT IN THE 20-25 KT RANGE WITH SOME GUSTS TO
30 KT FOR ALL WATERS AND SOUNDS...EXCLUDING THE
BAY...PAMLICO...AND NEUSE RIVERS...THOUGH OCNL GUSTS TO 25 KT ARE
CERTAINLY POSSIBLE PER HRRR FCST. SEAS WILL BUILD DRAMATICALLY
TONIGHT AND PEAK IN THE 5 TO 8 FT RANGE...HIGHEST OUTER CENTRAL
AND NRN WATERS. WINDS WILL COME DOWN A BIT TO 10-20 KT ON SUNDAY
BUT SEAS WILL REMAIN ELEVATED ABOVE 6 FT.
LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 330 PM SAT...MODELS REMAIN IN GOOD AGREEMENT WITH FINAL CAA
SURGE PRODUCING N-NE WINDS 20-25 KT OVER MOST OF WATERS SUN NIGHT
INTO MONDAY...AND EXTENDED SCA HEADLINES ACCORDINGLY. WINDS
DIMINISH QUICKLY LATE MON AND MON NIGHT. SFC RIDGE AXIS EXTENDING
W TO E ACROSS WATERS WILL LEAD TO LIGHT AND SOMEWHAT VRBL
CONDITIONS TUE-THU.
LATEST WAVE GDNC SUPPORTS PREVIOUS FCST WTIH SEAS BUILDING TO 5-7
FT SUN NIGHT...THEN SUBSIDING ON MONDAY WITH DIMINISHING WINDS.
HEIGHTS MAINLY 2-3 FT TUE-THU.
&&
.CLIMATE...
RECORD MIN TEMPS FOR 10/19 (MONDAY)
LOCATION TEMP/YEAR
NEW BERN 33/1948 (KEWN ASOS)
CAPE HATTERAS 39/1978 (KHSE ASOS)
GREENVILLE 33/1970 (COOP - NOT KPGV AWOS)
MOREHEAD CITY 37/1967 (COOP - NOT KMRH ASOS)
KINSTON 30/1973 (COOP - NOT KISO AWOS)
JACKSONVILLE 36/1992 (KNCA AWOS)
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT MONDAY FOR AMZ135.
SMALL CRAFT ADVISORY UNTIL 11 AM EDT SUNDAY FOR AMZ130-131.
SMALL CRAFT ADVISORY UNTIL 5 PM EDT MONDAY FOR AMZ150-152-154.
SMALL CRAFT ADVISORY UNTIL 2 PM EDT MONDAY FOR AMZ156-158.
&&
$$
SYNOPSIS...TL
NEAR TERM...JME/HSA/TL
SHORT TERM...TL
LONG TERM...JBM
AVIATION...JME/TL
MARINE...JME/JBM/HSA/TL
CLIMATE...MHX
AREA FORECAST DISCUSSION
NWS BISMARCK ND
930 PM CDT MON OCT 19 2015
.UPDATE...
ISSUED AT 927 PM CDT MON OCT 19 2015
THE FORECAST FOR THE REMAINDER OF THE NIGHT REMAINS ON TRACK AND
BLENDED TO A TIME LAGGED ENSEMBLE OF HRRR ITERATIONS THROUGH ITS
01 UTC RUN. THE BOWMAN ARB RADAR THROUGH 0220 UTC IS SHOWING THE
FIRST FEW RAIN SHOWERS CROSSING THE BORDER INTO SOUTHWEST NORTH
DAKOTA IN ASSOCIATION WITH THE SHORTWAVE NOW ACROSS SOUTHEAST
MONTANA.
UPDATE ISSUED AT 637 PM CDT MON OCT 19 2015
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE AS LIGHT RAIN
REMAINS LIKELY ACROSS THE WEST AND NORTH CENTRAL LATE TONIGHT INTO
TUESDAY MORNING ASSOCIATED WITH THE SHORTWAVE ACROSS NORTHEAST
WYOMING AS OF 23 UTC THAT WILL CONTINUE TO PROPAGATE NORTHEAST
THROUGH THE EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 325 PM CDT MON OCT 19 2015
MINIMAL THUNDERSTORM CHANCES IN THE FAR SOUTHWEST HIGHLIGHT THE
SHORT TERM PERIOD.
CURRENTLY...SURFACE HIGH PRESSURE IS SITUATED OVER SOUTHEAST
SASKATCHEWAN INTO WESTERN NORTH DAKOTA...WITH A NORTHEAST SURFACE
FLOW OVER THE EASTERN DAKOTAS...TRANSITIONING INTO A SOUTHEAST FLOW
OVER EASTERN MONTANA. HIGH CLOUDS WERE BEGINNING TO ENCROACH UPON
WESTERN NORTH DAKOTA AS ENERGY WITHIN AN ELONGATED UPPER LEVEL
TROUGH OVER THE WESTERN U.S. APPROACHES THE NORTHERN PLAINS.
TONIGHT...UPPER LEVEL RIDGING CURRENTLY OVER THE WESTERN AND CENTRAL
DAKOTAS WILL BREAK DOWN WITH LEAD SHORTWAVE ENERGY PROPAGATING
INTO THE NORTHERN PLAINS. MESOSCALE MODELS ARE IN GOOD AGREEMENT
IN BRINGING A BAND OF SHOWERS NORTHEAST ACROSS THE FORECAST AREA
TONIGHT. ENTERING THE FAR SOUTHWEST AROUND 02-04 UTC AND LIFTING
INTO THE FAR NORTHERN TIER COUNTIES BY AROUND 12 UTC TUESDAY. THE
INSTABILITY ALOFT IS NOT VERY IMPRESSIVE...BUT A FEW RUMBLES OF
THUNDER MAY BE POSSIBLE OVER THE FAR SOUTHWEST LATE THIS EVENING
INTO THE EARLY OVERNIGHT HOURS...CLOSEST TO THE UPPER LEVEL
SUPPORT. THUS WILL KEEP A MENTION OF THUNDER FAR SOUTHWEST.
TUESDAY...THE AFOREMENTIONED ELONGATED UPPER TROUGH SPLITS WITH THE
NORTHERN STREAM ENERGY TRACKING ALONG THE INTERNATIONAL BORDER. THUS
SHOWER CHANCES ON TUESDAY WILL REMAIN ALONG THE INTERNATIONAL BORDER
WHERE THE ENERGY FROM THE UPPER LEVEL TROUGH AND LOW LEVEL
CONVERGENCE ASSOCIATED WITH AN INVERTED SURFACE TROUGH
COINCIDE...WHILE THE SOUTH REMAINS DRY. THE INCREASED CLOUDS AND
SHOWERS NORTH WILL ALSO KEEP TEMPERATURES IN THE 50S...WITH 60S
CENTRAL AND SOUTH.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 325 PM CDT MON OCT 19 2015
TUESDAY EVENING THE UPPER LEVEL TROUGH AND ATTENDANT SURFACE
TROUGH/COLD FRONT MOVES EAST ACROSS WESTERN AND CENTRAL NORTH
DAKOTA. THE MODELS INDICATE THE BEST DYNAMICS OVER NORTHERN NORTH
DAKOTA TUESDAY EVENING...WITH THE UPPER TROUGH MOVING EAST OF OUR
AREA AFTER MIDNIGHT. THUS WILL KEEP CHANCES OF RAIN SHOWERS OVER
NORTHWEST AND NORTH CENTRAL NORTH DAKOTA DURING THE EVENING...THEN
DECREASING CLOUDS FROM WEST TO EAST AFTER MIDNIGHT. LOWS TUESDAY
NIGHT FROM THE MID 30S NORTHWEST TO MID 40S IN THE JAMES VALLEY.
COOLER AIR MOVING INTO THE REGION...WITH DRY HIGH PRESSURE OVER THE
STATE WEDNESDAY. HIGHS WEDNESDAY IN THE 50S...AND LOWS IN THE LOW TO
MID 30S.
WARMER ON THURSDAY AS A FAIRLY STRONG SOUTHERLY FLOW DEVELOPS WITH A
LOW LEVEL JET MOVING NORTHWARD FROM THE SOUTHERN AND CENTRAL PLAINS.
GULF MOISTURE ALSO MOVING NORTH...AND BY THURSDAY AFTERNOON LOOK FOR
HIGHS IN THE 60S AND A CHANCE OF SHOWERS OVER SOUTHERN NORTH DAKOTA.
THURSDAY NIGHT AND FRIDAY ARE THE BEST CHANCES OF RAIN SHOWERS
ACROSS WESTERN AND CENTRAL NORTH DAKOTA AS A GOOD UPPER LEVEL
SHORTWAVE MOVES NORTHEASTWARD FROM THE 4-CORNERS AREA AND PLENTY OF
GULF MOISTURE CONTINUES MOVING NORTH INTO THE NORTHERN PLAINS.
RAIN SHOWERS TAPERING OFF FRIDAY NIGHT AS MORE ZONAL FLOW ALOFT
TAKES HOLD. AS OF NOW THE WEEKEND LOOKS ON THE DRY SIDE WITH
SEASONABLE TEMPERATURES...HIGHS MAINLY IN THE 50S AND LOWS IN THE
30S.
THE MODELS HINT AT THE NEXT CHANCE OF RAIN SHOWERS MOVING IN ON
MONDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 927 PM CDT MON OCT 19 2015
MVFR CONDITIONS POSSIBLE IN LIGHT RAIN AT KDIK/KMOT/KISN LATE
TONIGHT INTO TUESDAY MORNING. PRECIPITATION FREE VFR CONDITIONS
EXPECTED AT KBIS/KJMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...TWH
LONG TERM...JV
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
106 PM CDT SUN OCT 18 2015
.UPDATE...
ISSUED AT 103 PM CDT SUN OCT 18 2015
NO SIGNIFICANT CHANGES FOR THE EARLY AFTERNOON UPDATE. A FEW
CLOUDS STARTING TO MOVE INTO THE SOUTHWEST...OTHERWISE SUNNY.
BREEZY CONDITIONS IN THE JAMES RIVER VALLEY WITH GUSTS TO AROUND
30 MPH.
UPDATE ISSUED AT 943 AM CDT SUN OCT 18 2015
LATEST WV LOOP SHOWS UPPER LOW MOVING ONTO THE NORTHERN CALIFORNIA
COAST. LEAD SHORTWAVE ENERGY IS LIFTING THROUGH THE NORTHERN
ROCKIES AND INTO THE NORTHERN HIGH PLAINS. UPPER LEVEL RIDGING
REMAINS OVER WESTERN AND CENTRAL NORTH DAKOTA...BUT WILL FLATTEN
DURING THE DAY DUE TO AFOREMENTIONED SHORTWAVE ENERGY...AND
ANOTHER NORTHERN STREAM WAVE. BREEZY EAST TODAY BUT OVERALL QUIET
WITH SOME INCREASING MID AND HIGH LEVEL CLOUDS WEST. SUNNY EAST.
FOR THE MORNING UPDATE...INCREASED CLOUDS AND MINIMAL POPS WEST
FOR TONIGHT. MESOSCALE MODELS AND THE ECMWF BRING INCREASING MID
LEVEL MOISTURE INTO WESTERN NORTH DAKOTA...AND LAST FEW ITERATIONS
OF THE HRRR HAVE BROUGHT SOME LIGHT QPF THROUGH NORTHEAST MONTANA.
WILL KEEP AN EYE ON HOW THINGS TREND THROUGH THE DAY BUT FOR NOW
DID NOT BRING ANY MENTION OF PRECIP INTO THE WORDED FORECAST IN
THE WEST TONIGHT AS ATMOSPHERE BELOW THIS MID LEVEL MOISTURE
REMAIN QUITE DRY.
UPDATE ISSUED AT 636 AM CDT SUN OCT 18 2015
FORECAST ON TRACK. HOURLY TEMPS WERE A LITTLE TOO HIGH ACROSS SOME
AREAS...THEREFORE BLENDED FORECAST TO CURRENT OBSERVATIONS.
OTHERWISE...NO CHANGES MADE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 301 AM CDT SUN OCT 18 2015
SURFACE HIGH PRESSURE WILL CONTINUE TO DRIFT AWAY FROM THE
FORECAST AREA TODAY...TO THE SOUTHEAST...WHILE A LEE SIDE TROUGH
THROUGH EASTERN MONTANA PUSHES THROUGH WILLISTON AND DICKINSON BY
SUNSET. THIS RESULTS IN SOUTHEAST SURFACE WINDS. MID LEVEL
SUPPORT WAS VERY WEAK AND WITH A LACK OF LOW LEVEL MOISTURE THE
TROUGH PASSAGE IS FORECAST TO BE DRY.
HIGH TEMPERATURES TODAY WILL BE 10 DEGREES ABOVE MID OCTOBER
NORMALS OVER THE JAMES RIVER VALLEY TO 20 DEGREES ABOVE NORMAL
AT HETTINGER.
A GUSTY SOUTHEAST WIND AHEAD OF THE TROUGH...WITH HIGHEST WIND
SPEEDS THROUGH THE JAMES RIVER VALLEY...WILL REMAIN BELOW WIND
ADVISORY CRITERIA. HIGHER HUMIDITY THROUGH THE JAMES VALLEY WILL
ACT TO DAMPEN FIRE WEATHER CONCERNS TODAY.
THE DRY TROUGH PASSES THROUGH THE REST OF THE FORECAST AREA
TONIGHT WITH PARTLY CLOUDY SKIES.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 301 AM CDT SUN OCT 18 2015
00Z GFS/ECMWF/CANADIAN MODELS ARE IN DECENT AGREEMENT EARLY IN
THE PERIOD SHOWING A MORE ACTIVE WEEK SETTING UP WITH THE FIRST
CHANCE OF PRECIP MONDAY NIGHT THROUGH TUESDAY WITH OUR REGION IN
SOUTHWEST FLOW AHEAD OF LONGWAVE TROUGH ACROSS INTERMOUNTAIN WEST
EARLY IN THE WEEK. FORECAST CONTINUES WITH MAINLY CHANCE POPS FOR
THIS SYSTEM. NEXT SYSTEM APPROACHES THE NORTHERN PLAINS ON
THURSDAY WITH MODELS SHOWING MORE SIGNIFICANT DIFFERENCES.
OPERATIONAL GFS IS MUCH FASTER WITH THIS SYSTEM AND FARTHER NORTH
WITH SURFACE LOW COMPARED TO GFS ENSEMBLES AND ECMWF. GFS HAS
PRECIP EAST OF NORTH DAKOTA EARLY FRIDAY WHILE ECMWF/CANADIAN
MODELS HOLD PRECIP ACROSS THE STATE FOR MUCH OF THE DAY. FORECAST
LEANS MORE TOWARD THE SLOWER SOLUTIONS AND MAINTAINS PRECIP
THROUGH FRIDAY. WITH REGARD TO TEMPERATURES...EXPECT THEM TO
CONTINUE TO RUN NEAR/ABOVE NORMAL WITH HIGHS MAINLY IN THE 50 AND
SOME LOW 60S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 103 PM CDT SUN OCT 18 2015
VFR CONDITIONS EXPECTED THROUGH THE 18Z FORECAST PERIOD. A DRY AND
WEAK COLD FRONT WILL MOVE THROUGH THE FORECAST AREA SHIFTING WINDS
FROM SOUTHERLY TODAY TO NORTHERLY MONDAY. MIGHT SEE A FEW
SPRINKLES FALLING FROM SOME MID-LEVEL CLOUDS...BUT TO SPARSELY
POPULATED TO EVEN MENTION A VCSH AT THIS TIME.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...JPM
LONG TERM...JNS
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
955 AM CDT SUN OCT 18 2015
.UPDATE...
ISSUED AT 943 AM CDT SUN OCT 18 2015
LATEST WV LOOP SHOWS UPPER LOW MOVING ONTO THE NORTHERN CALIFORNIA
COAST. LEAD SHORTWAVE ENERGY IS LIFTING THROUGH THE NORTHERN
ROCKIES AND INTO THE NORTHERN HIGH PLAINS. UPPER LEVEL RIDGING
REMAINS OVER WESTERN AND CENTRAL NORTH DAKOTA...BUT WILL FLATTEN
DURING THE DAY DUE TO AFOREMENTIONED SHORTWAVE ENERGY...AND
ANOTHER NORTHERN STREAM WAVE. BREEZY EAST TODAY BUT OVERALL QUIET
WITH SOME INCREASING MID AND HIGH LEVEL CLOUDS WEST. SUNNY EAST.
FOR THE MORNING UPDATE...INCREASED CLOUDS AND MINIMAL POPS WEST
FOR TONIGHT. MESOSCALE MODELS AND THE ECMWF BRING INCREASING MID
LEVEL MOISTURE INTO WESTERN NORTH DAKOTA...AND LAST FEW ITERATIONS
OF THE HRRR HAVE BROUGHT SOME LIGHT QPF THROUGH NORTHEAST MONTANA.
WILL KEEP AN EYE ON HOW THINGS TREND THROUGH THE DAY BUT FOR NOW
DID NOT BRING ANY MENTION OF PRECIP INTO THE WORDED FORECAST IN
THE WEST TONIGHT AS ATMOSPHERE BELOW THIS MID LEVEL MOISTURE
REMAIN QUITE DRY.
UPDATE ISSUED AT 636 AM CDT SUN OCT 18 2015
FORECAST ON TRACK. HOURLY TEMPS WERE A LITTLE TOO HIGH ACROSS SOME
AREAS...THEREFORE BLENDED FORECAST TO CURRENT OBSERVATIONS.
OTHERWISE...NO CHANGES MADE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 301 AM CDT SUN OCT 18 2015
SURFACE HIGH PRESSURE WILL CONTINUE TO DRIFT AWAY FROM THE
FORECAST AREA TODAY...TO THE SOUTHEAST...WHILE A LEE SIDE TROUGH
THROUGH EASTERN MONTANA PUSHES THROUGH WILLISTON AND DICKINSON BY
SUNSET. THIS RESULTS IN SOUTHEAST SURFACE WINDS. MID LEVEL
SUPPORT WAS VERY WEAK AND WITH A LACK OF LOW LEVEL MOISTURE THE
TROUGH PASSAGE IS FORECAST TO BE DRY.
HIGH TEMPERATURES TODAY WILL BE 10 DEGREES ABOVE MID OCTOBER
NORMALS OVER THE JAMES RIVER VALLEY TO 20 DEGREES ABOVE NORMAL
AT HETTINGER.
A GUSTY SOUTHEAST WIND AHEAD OF THE TROUGH...WITH HIGHEST WIND
SPEEDS THROUGH THE JAMES RIVER VALLEY...WILL REMAIN BELOW WIND
ADVISORY CRITERIA. HIGHER HUMIDITY THROUGH THE JAMES VALLEY WILL
ACT TO DAMPEN FIRE WEATHER CONCERNS TODAY.
THE DRY TROUGH PASSES THROUGH THE REST OF THE FORECAST AREA
TONIGHT WITH PARTLY CLOUDY SKIES.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 301 AM CDT SUN OCT 18 2015
00Z GFS/ECMWF/CANADIAN MODELS ARE IN DECENT AGREEMENT EARLY IN
THE PERIOD SHOWING A MORE ACTIVE WEEK SETTING UP WITH THE FIRST
CHANCE OF PRECIP MONDAY NIGHT THROUGH TUESDAY WITH OUR REGION IN
SOUTHWEST FLOW AHEAD OF LONGWAVE TROUGH ACROSS INTERMOUNTAIN WEST
EARLY IN THE WEEK. FORECAST CONTINUES WITH MAINLY CHANCE POPS FOR
THIS SYSTEM. NEXT SYSTEM APPROACHES THE NORTHERN PLAINS ON
THURSDAY WITH MODELS SHOWING MORE SIGNIFICANT DIFFERENCES.
OPERATIONAL GFS IS MUCH FASTER WITH THIS SYSTEM AND FARTHER NORTH
WITH SURFACE LOW COMPARED TO GFS ENSEMBLES AND ECMWF. GFS HAS
PRECIP EAST OF NORTH DAKOTA EARLY FRIDAY WHILE ECMWF/CANADIAN
MODELS HOLD PRECIP ACROSS THE STATE FOR MUCH OF THE DAY. FORECAST
LEANS MORE TOWARD THE SLOWER SOLUTIONS AND MAINTAINS PRECIP
THROUGH FRIDAY. WITH REGARD TO TEMPERATURES...EXPECT THEM TO
CONTINUE TO RUN NEAR/ABOVE NORMAL WITH HIGHS MAINLY IN THE 50 AND
SOME LOW 60S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 943 AM CDT SUN OCT 18 2015
A DRY TROUGH OF LOW PRESSURE WILL MOVE OUT OF MONTANA AND ACROSS
NORTH DAKOTA DURING THE TAF VALID PERIOD. VFR WEATHER AT ALL TAF
SITES. DURING THE DAYLIGHT HOURS SUNDAY...AHEAD OF THE
TROUGH...SOUTHEAST SURFACE WINDS WILL GUST TO 25 KNOTS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...JPM
LONG TERM...JNS
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
700 PM EDT SUN OCT 18 2015
.SYNOPSIS...
A DEEP UPPER LEVEL TROUGH OVER EASTERN CANADA WILL LIFT
OUT...LEADING TO A MILDER WEATHER PATTERN WITH LIMITED
OPPORTUNITIES FOR RAIN FOR MUCH OF THE UPCOMING WEEK...WITH
TEMPERATURES RISING NEAR TO ABOVE NORMAL FOR LATE OCTOBER.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
STILL A FEW RAIN AND SNOW SHOWERS ON RADAR...BUT THESE SHOULD BE
GONE SOON...AS THE SUN SETS.
CURRENT FCST PACKAGE IN GOOD SHAPE.
EARLIER DISCUSSION BELOW.
RADAR IS FILLED WITH FAST MOVING SCATTERED SHOWERS. LOCALLY WE ARE
VARYING BETWEEN THE UPPER 30S AND LOWER 40S DEPENDING ON WHETHER
WE HAVE PRECIPITATION IN PROGRESS...WITH IT TENDING TOWARD WET
SNOW WHEN IT IS ACTUALLY DOING SOMETHING. THE HRRR INDICATES THESE
SHOWERS WILL MAX OUT HERE IN THE NEXT HOUR OR TWO BEFORE DWINDLING
AS THE UPPER FORCING ASSOCIATED WITH THE LEFT JET EXIT REGION
SWINGS OFF TO OUR EAST.
THE GREATEST RISK FOR SNOW TO ACTUALLY WHITEN THE
GROUND...ESPECIALLY ON GRASSY SURFACES...WILL BE DOWNWIND OF LAKE
ERIE OVER THE HIGHER ELEVATIONS OF THE ALLEGHENY FOREST REGION.
MORE DOWNWIND OUT OF THE NORTHERN HIGHER ELEVATIONS...WET SNOW OR
A MIX OF RAIN AND SNOW WILL MEAN MOST AREAS WILL NOT EXPERIENCE
ANY SNOW ACCUMS.
HIGH PRESSURE WILL MIGRATE EWD FROM THE LWR OH VALLEY LATER TODAY
AND BE CENTERED OVER THE MD/WV PANHANDLE BY 12Z MONDAY. THE
INCREASING LARGE SCALE SUBSIDENCE AND BACKING LOW LEVEL
TRAJECTORIES WILL SPELL AN END TO THE LAKE EFFECT SHOWER ACTIVITY.
MORE IMPORTANTLY THERE SHOULD ALSO BE A DECREASE IN CLOUD
COVER...SETTING THE STAGE FOR A WIDESPREAD KILLING FREEZE.
HAVE CONTINUED THE FREEZE WARNING WITH HIGH CONFIDENCE IN ENDING
THE GROWING SEASON.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
HIGH PRESSURE WILL SETTLE OFF TO THE SOUTHEAST OF THE REGION
MONDAY...ALLOWING A MILDER SOUTHWEST FLOW TO DEVELOP. IT SHOULD
LEAD TO A BRIGHT DAY WITH HIGHS REBOUNDING...AVERAGING SOME 5 TO
15 DEGREES WARMER THAN TODAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
UPPER TROF CURRENTLY OVER THE NERN NORTH AMERICA IS FORECAST TO
LIFT/PROGRESS EWD THROUGH EARLY THIS WEEK. UPPER LONGWAVE TROF
ALONG THE WEST COAST IS FORECAST TO DROP SOUTH AND CLOSE OFF OVER
THE DESERT SW. THIS WILL ALLOW HEIGHT TO RISE SLOWLY OVER THE
EASTERN HALF OF THE COUNTRY THROUGH THE WEEK...BUT AN ACTIVE NRN
STREAM PATTERN SHOULD KEEP THE UPPER RIDGE OVER THE CENTRAL AND
SERN U.S. FROM EXPANDING TOO FAR NORTH.
A MILDER SPLIT-FLOW WEATHER PATTERN IS EXPECTED TO DEVELOP AND
PERSIST THROUGH MUCH OF NEXT WEEK. THE GLOBAL MODELS AND ENSEMBLE
PREDICTION SYSTEMS INDICATE THAT PCPN OPPORTUNITIES WILL REMAIN
VERY LIMITED ACROSS THE AREA. THAT SAID THERE IS SOME SPREAD IN
KEY SYNOPTIC FEATURES OVER THE LOWER 48...NAMELY THE NRN STREAM
SHORTWAVE EVOLUTION CROSSING SERN CANADA/GRT LKS REGION AROUND
THURSDAY. THE 18/00Z ECMWF IS DEEPER/SLOWER WITH THE H5 SYSTEM AND
FAVORS A MORE PRONOUNCED MID LEVEL TROUGH IN THE NORTHEAST THURS
NGT-FRI. THE GFS/GEFS AND GEM ARE MORE PROGRESSIVE WITH THE NRN
STREAM WAVE WHICH ALLOWS UPPER RIDGING TO BULGE NWD FROM THE
GOMEX.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
UPPER LVL TROUGH AND ASSOC COLD AIR ALOFT IS PRODUCING SCT SHSNRA
ACROSS CENTRAL PA AS OF 21Z. ALTHOUGH WIDESPREAD VFR CONDS NOTED
AT 21Z...A BRIEF REDUCTION FROM PASSING SHOWERS REMAINS POSSIBLE
THRU ARND 23Z.
HIGH PRESSURE WILL BUILD INTO THE REGION TONIGHT...BRINGING AN END
TO THE THREAT OF SHSNRA BY 00Z. FOCUS WILL THEN SHIFT TOWARD
THE POSSIBILITY OF LATE NIGHT VALLEY FOG...AS SKIES CLEAR AND THE
WIND DIMINISHES. WOULD BE WARY OF WHAT APPEARS TO BE OVERLY
OPTIMISTIC MOS GUIDANCE...WHICH INDICATES NO FOG. OVERNIGHT CLEAR
SKIES/CALM WIND THIS TIME OF YEAR USUALLY YIELDS AT LEAST PATCHY
FOG...AS THE LATEST SREF AND DOWNSCALED NAM SUGGEST. WILL AWAIT
LATER MODEL GUIDANCE FOR POSSIBLE INCLUSION OF LATE NIGHT FOG IN
THE FCST UPDATE AT 00Z.
ANY POSSIBLE VALLEY FOG SHOULD BURN OFF SHORTLY AFTER 12Z MONDAY.
HIGH PRESSURE OVR THE REGION SHOULD ENSURE A NEAR CERTAINTY OF VFR
CONDS FOR THE REST OF THE DAY.
OUTLOOK...
TUE-WED...MAINLY VFR. NO SIG WX EXPECTED.
THU...MAINLY VFR...BUT A FEW SHOWERS POSSIBLE...MAINLY N PA.
FRI...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 3 AM TO 9 AM EDT MONDAY FOR PAZ019-025>028-
034>036-045-046-049>053-056>059-063>066.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE/MARTIN
SHORT TERM...LA CORTE
LONG TERM...GARTNER/STEINBUGL
AVIATION...FITZGERALD/LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
510 PM EDT SUN OCT 18 2015
.SYNOPSIS...
A DEEP UPPER LEVEL TROUGH OVER EASTERN CANADA WILL LIFT
OUT...LEADING TO A MILDER WEATHER PATTERN WITH LIMITED
OPPORTUNITIES FOR RAIN FOR MUCH OF THE UPCOMING WEEK...WITH
TEMPERATURES RISING NEAR TO ABOVE NORMAL FOR LATE OCTOBER.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
RADAR IS FILLED WITH FAST MOVING SCATTERED SHOWERS. LOCALLY WE ARE
VARYING BETWEEN THE UPPER 30S AND LOWER 40S DEPENDING ON WHETHER
WE HAVE PRECIPITATION IN PROGRESS...WITH IT TENDING TOWARD WET
SNOW WHEN IT IS ACTUALLY DOING SOMETHING. THE HRRR INDICATES THESE
SHOWERS WILL MAX OUT HERE IN THE NEXT HOUR OR TWO BEFORE DWINDLING
AS THE UPPER FORCING ASSOCIATED WITH THE LEFT JET EXIT REGION
SWINGS OFF TO OUR EAST.
THE GREATEST RISK FOR SNOW TO ACTUALLY WHITEN THE
GROUND...ESPECIALLY ON GRASSY SURFACES...WILL BE DOWNWIND OF LAKE
ERIE OVER THE HIGHER ELEVATIONS OF THE ALLEGHENY FOREST REGION.
MORE DOWNWIND OUT OF THE NORTHERN HIGHER ELEVATIONS...WET SNOW OR
A MIX OF RAIN AND SNOW WILL MEAN MOST AREAS WILL NOT EXPERIENCE
ANY SNOW ACCUMS.
HIGH PRESSURE WILL MIGRATE EWD FROM THE LWR OH VALLEY LATER TODAY
AND BE CENTERED OVER THE MD/WV PANHANDLE BY 12Z MONDAY. THE
INCREASING LARGE SCALE SUBSIDENCE AND BACKING LOW LEVEL
TRAJECTORIES WILL SPELL AN END TO THE LAKE EFFECT SHOWER ACTIVITY.
MORE IMPORTANTLY THERE SHOULD ALSO BE A DECREASE IN CLOUD
COVER...SETTING THE STAGE FOR A WIDESPREAD KILLING FREEZE.
HAVE CONTINUED THE FREEZE WARNING WITH HIGH CONFIDENCE IN ENDING
THE GROWING SEASON.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
HIGH PRESSURE WILL SETTLE OFF TO THE SOUTHEAST OF THE REGION
MONDAY...ALLOWING A MILDER SOUTHWEST FLOW TO DEVELOP. IT SHOULD
LEAD TO A BRIGHT DAY WITH HIGHS REBOUNDING...AVERAGING SOME 5 TO
15 DEGREES WARMER THAN TODAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
UPPER TROF CURRENTLY OVER THE NERN NORTH AMERICA IS FORECAST TO
LIFT/PROGRESS EWD THROUGH EARLY THIS WEEK. UPPER LONGWAVE TROF
ALONG THE WEST COAST IS FORECAST TO DROP SOUTH AND CLOSE OFF OVER
THE DESERT SW. THIS WILL ALLOW HEIGHT TO RISE SLOWLY OVER THE
EASTERN HALF OF THE COUNTRY THROUGH THE WEEK...BUT AN ACTIVE NRN
STREAM PATTERN SHOULD KEEP THE UPPER RIDGE OVER THE CENTRAL AND
SERN U.S. FROM EXPANDING TOO FAR NORTH.
A MILDER SPLIT-FLOW WEATHER PATTERN IS EXPECTED TO DEVELOP AND
PERSIST THROUGH MUCH OF NEXT WEEK. THE GLOBAL MODELS AND ENSEMBLE
PREDICTION SYSTEMS INDICATE THAT PCPN OPPORTUNITIES WILL REMAIN
VERY LIMITED ACROSS THE AREA. THAT SAID THERE IS SOME SPREAD IN
KEY SYNOPTIC FEATURES OVER THE LOWER 48...NAMELY THE NRN STREAM
SHORTWAVE EVOLUTION CROSSING SERN CANADA/GRT LKS REGION AROUND
THURSDAY. THE 18/00Z ECMWF IS DEEPER/SLOWER WITH THE H5 SYSTEM AND
FAVORS A MORE PRONOUNCED MID LEVEL TROUGH IN THE NORTHEAST THURS
NGT-FRI. THE GFS/GEFS AND GEM ARE MORE PROGRESSIVE WITH THE NRN
STREAM WAVE WHICH ALLOWS UPPER RIDGING TO BULGE NWD FROM THE
GOMEX.
&&
.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
UPPER LVL TROUGH AND ASSOC COLD AIR ALOFT IS PRODUCING SCT SHSNRA
ACROSS CENTRAL PA AS OF 21Z. ALTHOUGH WIDESPREAD VFR CONDS NOTED
AT 21Z...A BRIEF REDUCTION FROM PASSING SHOWERS REMAINS POSSIBLE
THRU ARND 23Z.
HIGH PRESSURE WILL BUILD INTO THE REGION TONIGHT...BRINGING AN END
TO THE THREAT OF SHSNRA BY 00Z. FOCUS WILL THEN SHIFT TOWARD
THE POSSIBILITY OF LATE NIGHT VALLEY FOG...AS SKIES CLEAR AND THE
WIND DIMINISHES. WOULD BE WARY OF WHAT APPEARS TO BE OVERLY
OPTIMISTIC MOS GUIDANCE...WHICH INDICATES NO FOG. OVERNIGHT CLEAR
SKIES/CALM WIND THIS TIME OF YEAR USUALLY YIELDS AT LEAST PATCHY
FOG...AS THE LATEST SREF AND DOWNSCALED NAM SUGGEST. WILL AWAIT
LATER MODEL GUIDANCE FOR POSSIBLE INCLUSION OF LATE NIGHT FOG IN
THE FCST UPDATE AT 00Z.
ANY POSSIBLE VALLEY FOG SHOULD BURN OFF SHORTLY AFTER 12Z MONDAY.
HIGH PRESSURE OVR THE REGION SHOULD ENSURE A NEAR CERTAINTY OF VFR
CONDS FOR THE REST OF THE DAY.
OUTLOOK...
TUE-WED...MAINLY VFR. NO SIG WX EXPECTED.
THU...MAINLY VFR...BUT A FEW SHOWERS POSSIBLE...MAINLY N PA.
FRI...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 3 AM TO 9 AM EDT MONDAY FOR PAZ019-025>028-
034>036-045-046-049>053-056>059-063>066.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...GARTNER/STEINBUGL
AVIATION...FITZGERALD/LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
358 PM EDT SUN OCT 18 2015
.SYNOPSIS...
A DEEP UPPER LEVEL TROUGH OVER EASTERN CANADA WILL LIFT
OUT...LEADING TO A MILDER WEATHER PATTERN WITH LIMITED
OPPORTUNITIES FOR RAIN FOR MUCH OF THE UPCOMING WEEK...WITH
TEMPERATURES RISING NEAR TO ABOVE NORMAL FOR LATE OCTOBER.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
RADAR IS FILLED WITH FAST MOVING SCATTERED SHOWERS. LOCALLY WE ARE
VARYING BETWEEN THE UPPER 30S AND LOWER 40S DEPENDING ON WHETHER
WE HAVE PRECIPITATION IN PROGRESS...WITH IT TENDING TOWARD WET
SNOW WHEN IT IS ACTUALLY DOING SOMETHING. THE HRRR INDICATES THESE
SHOWERS WILL MAX OUT HERE IN THE NEXT HOUR OR TWO BEFORE DWINDLING
AS THE UPPER FORCING ASSOCIATED WITH THE LEFT JET EXIT REGION
SWINGS OFF TO OUR EAST.
THE GREATEST RISK FOR SNOW TO ACTUALLY WHITEN THE
GROUND...ESPECIALLY ON GRASSY SURFACES...WILL BE DOWNWIND OF LAKE
ERIE OVER THE HIGHER ELEVATIONS OF THE ALLEGHENY FOREST REGION.
MORE DOWNWIND OUT OF THE NORTHERN HIGHER ELEVATIONS...WET SNOW OR
A MIX OF RAIN AND SNOW WILL MEAN MOST AREAS WILL NOT EXPERIENCE
ANY SNOW ACCUMS.
HIGH PRESSURE WILL MIGRATE EWD FROM THE LWR OH VALLEY LATER TODAY
AND BE CENTERED OVER THE MD/WV PANHANDLE BY 12Z MONDAY. THE
INCREASING LARGE SCALE SUBSIDENCE AND BACKING LOW LEVEL
TRAJECTORIES WILL SPELL AN END TO THE LAKE EFFECT SHOWER ACTIVITY.
MORE IMPORTANTLY THERE SHOULD ALSO BE A DECREASE IN CLOUD
COVER...SETTING THE STAGE FOR A WIDESPREAD KILLING FREEZE.
HAVE CONTINUED THE FREEZE WARNING WITH HIGH CONFIDENCE IN ENDING
THE GROWING SEASON.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
HIGH PRESSURE WILL SETTLE OFF TO THE SOUTHEAST OF THE REGION
MONDAY...ALLOWING A MILDER SOUTHWEST FLOW TO DEVELOP. IT SHOULD
LEAD TO A BRIGHT DAY WITH HIGHS REBOUNDING...AVERAGING SOME 5 TO
15 DEGREES WARMER THAN TODAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
UPPER TROF CURRENTLY OVER THE NERN NORTH AMERICA IS FORECAST TO
LIFT/PROGRESS EWD THROUGH EARLY THIS WEEK. UPPER LONGWAVE TROF
ALONG THE WEST COAST IS FORECAST TO DROP SOUTH AND CLOSE OFF OVER
THE DESERT SW. THIS WILL ALLOW HEIGHT TO RISE SLOWLY OVER THE
EASTERN HALF OF THE COUNTRY THROUGH THE WEEK...BUT AN ACTIVE NRN
STREAM PATTERN SHOULD KEEP THE UPPER RIDGE OVER THE CENTRAL AND
SERN U.S. FROM EXPANDING TOO FAR NORTH.
A MILDER SPLIT-FLOW WEATHER PATTERN IS EXPECTED TO DEVELOP AND
PERSIST THROUGH MUCH OF NEXT WEEK. THE GLOBAL MODELS AND ENSEMBLE
PREDICTION SYSTEMS INDICATE THAT PCPN OPPORTUNITIES WILL REMAIN
VERY LIMITED ACROSS THE AREA. THAT SAID THERE IS SOME SPREAD IN
KEY SYNOPTIC FEATURES OVER THE LOWER 48...NAMELY THE NRN STREAM
SHORTWAVE EVOLUTION CROSSING SERN CANADA/GRT LKS REGION AROUND
THURSDAY. THE 18/00Z ECMWF IS DEEPER/SLOWER WITH THE H5 SYSTEM AND
FAVORS A MORE PRONOUNCED MID LEVEL TROUGH IN THE NORTHEAST THURS
NGT-FRI. THE GFS/GEFS AND GEM ARE MORE PROGRESSIVE WITH THE NRN
STREAM WAVE WHICH ALLOWS UPPER RIDGING TO BULGE NWD FROM THE
GOMEX.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
SATELLITE SHOWS A FAIRLY TYPICAL COOL SEASON SHIELD OF STRATO-CU
CLOUDINESS UNDER THE COLD CYCLONIC FLOW AROUND THE DEEP UPPER LOW
OVER EASTERN CANADA. WE WILL SEE THIS PATTERN BE REPEATED MANY
TIMES OVER THE NEXT SEVERAL MONTHS.
MVFR CEILINGS WILL TEND TO FAVOR THE HIGHER ELEVATION TERMINALS
WITH BRIEF REDUCTIONS TO IFR POSSIBLE EVEN DOWN INTO CENTRAL AREAS
AS FAST MOVING CELLULAR SHOWERS RACE TO THE SOUTHEAST.
CONDITIONS WILL IMPROVE LATER TODAY INTO THE EVENING AS HIGH
PRESSURE MOVES EASTWARD AND SHUTS OFF THE COLD LAKE EFFECT FLOW.
THE WIND WILL WEAKEN AND BECOME LIGHT AND VARIABLE OVERNIGHT.
OUTLOOK...
MON-WED...MAINLY VFR. NO SIG WX EXPECTED.
THU...MAINLY VFR...BUT A FEW SHOWERS POSSIBLE...MAINLY N PA.
FRI...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 3 AM TO 9 AM EDT MONDAY FOR PAZ019-025>028-
034>036-045-046-049>053-056>059-063>066.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...GARTNER/STEINBUGL
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
218 PM EDT SUN OCT 18 2015
.SYNOPSIS...
A DEEP UPPER LEVEL TROUGH OVER EASTERN CANADA WILL LIFT
OUT...LEADING TO A MILDER WEATHER PATTERN WITH LIMITED
OPPORTUNITIES FOR RAIN FOR MUCH OF THE UPCOMING WEEK...WITH
TEMPERATURES RISING NEAR TO ABOVE NORMAL FOR LATE OCTOBER.
&&
.NEAR TERM /THROUGH TONIGHT/...
RADAR IS FILLED WITH FAST MOVING SCATTERED SHOWERS. LOCALLY WE ARE
VARYING BETWEEN THE UPPER 30S AND LOWER 40S DEPENDING ON WHETHER
WE HAVE PRECIPITATION IN PROGRESS...WITH IT TENDING TOWARD WET
SNOW WHEN IT IS ACTUALLY DOING SOMETHING. THE HRRR INDICATES THESE
SHOWERS WILL MAX OUT HERE IN THE NEXT HOUR OR TWO BEFORE DWINDLING
AS THE UPPER FORCING ASSOCIATED WITH THE LEFT JET EXIT REGION
SWINGS OFF TO OUR EAST.
THE GREATEST RISK FOR SNOW TO ACTUALLY WHITEN THE
GROUND...ESPECIALLY ON GRASSY SURFACES...WILL BE DOWNWIND OF LAKE
ERIE OVER THE HIGHER ELEVATIONS OF THE ALLEGHENY FOREST REGION.
MORE DOWNWIND OUT OF THE NORTHERN HIGHER ELEVATIONS...WET SNOW OR
A MIX OF RAIN AND SNOW WILL MEAN MOST AREAS WILL NOT EXPERIENCE
ANY SNOW ACCUMS.
HIGH PRESSURE WILL MIGRATE EWD FROM THE LWR OH VALLEY LATER TODAY
AND BE CENTERED OVER THE MD/WV PANHANDLE BY 12Z MONDAY. THE
INCREASING LARGE SCALE SUBSIDENCE AND BACKING LOW LEVEL
TRAJECTORIES WILL SPELL AN END TO THE LAKE EFFECT SHOWER ACTIVITY.
MORE IMPORTANTLY THERE SHOULD ALSO BE A DECREASE IN CLOUD
COVER...SETTING THE STAGE FOR A WIDESPREAD KILLING FREEZE.
HAVE CONTINUED THE FREEZE WARNING WITH HIGH CONFIDENCE IN ENDING
THE GROWING SEASON.
&&
.SHORT TERM /MONDAY/...
HIGH PRESSURE WILL SETTLE OFF TO THE SOUTHEAST OF THE REGION
MONDAY...ALLOWING A MILDER SOUTHWEST FLOW TO DEVELOP. IT SHOULD
LEAD TO A BRIGHT DAY WITH HIGHS REBOUNDING...AVERAGING SOME 5 TO
15 DEGREES WARMER THAN TODAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
A MILDER SPLIT-FLOW WEATHER PATTERN IS EXPECTED TO DEVELOP AND
PERSIST THROUGH MUCH OF NEXT WEEK. THE GLOBAL MODELS AND ENSEMBLE
PREDICTION SYSTEMS INDICATE THAT PCPN OPPORTUNITIES WILL REMAIN
VERY LIMITED ACROSS THE AREA. THAT SAID THERE IS SOME SPREAD IN
KEY SYNOPTIC FEATURES OVER THE LOWER 48...NAMELY THE NRN STREAM
SHORTWAVE EVOLUTION CROSSING SERN CANADA/GRT LKS REGION AROUND
THURSDAY. THE 18/00Z ECMWF IS DEEPER/SLOWER WITH THE H5 SYSTEM AND
FAVORS A MORE PRONOUNCED MID LEVEL TROUGH IN THE NORTHEAST THURS
NGT-FRI. THE GFS/GEFS AND GEM ARE MORE PROGRESSIVE WITH THE NRN
STREAM WAVE WHICH ALLOWS UPPER RIDGING TO BULGE NWD FROM THE
GOMEX.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
SATELLITE SHOWS A FAIRLY TYPICAL COOL SEASON SHIELD OF STRATO-CU
CLOUDINESS UNDER THE COLD CYCLONIC FLOW AROUND THE DEEP UPPER LOW
OVER EASTERN CANADA. WE WILL SEE THIS PATTERN BE REPEATED MANY
TIMES OVER THE NEXT SEVERAL MONTHS.
MVFR CEILINGS WILL TEND TO FAVOR THE HIGHER ELEVATION TERMINALS
WITH BRIEF REDUCTIONS TO IFR POSSIBLE EVEN DOWN INTO CENTRAL AREAS
AS FAST MOVING CELLULAR SHOWERS RACE TO THE SOUTHEAST.
CONDITIONS WILL IMPROVE LATER TODAY INTO THE EVENING AS HIGH
PRESSURE MOVES EASTWARD AND SHUTS OFF THE COLD LAKE EFFECT FLOW.
THE WIND WILL WEAKEN AND BECOME LIGHT AND VARIABLE OVERNIGHT.
OUTLOOK...
MON-WED...MAINLY VFR. NO SIG WX EXPECTED.
THU...MAINLY VFR...BUT A FEW SHOWERS POSSIBLE...MAINLY N PA.
FRI...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 3 AM TO 9 AM EDT MONDAY FOR PAZ019-025>028-
034>036-045-046-049>053-056>059-063>066.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...STEINBUGL
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
339 AM MDT TUE OCT 20 2015
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 338 AM MDT TUE OCT 20 2015
CONVECTION CONTINUES TO ROLL NORTHEAST ACROSS THE REGION THIS
MORNING WITH BULK OF ACTIVITY ACROSS OUR CENTRAL ZONES. INTENSITY
HAS BACKED DOWN...ALTHOUGH STILL SEEING A FEW STRONGER CELLS
PRODUCING FREQUENT LIGHTNING. SHRTWV ROTATING NORTHEAST WILL
CONTINUE TO DRIVE THIS ACTIVITY INTO OUR NORTHERN ZONES...WHERE
CONDS ARE COOLER AND EXPECT THIS ACTIVITY TO DIMINISH OR SLOWLY
DISSIPATE AS IT LIFTS TOWARDS WYOMING. HRR AND RAP BOTH IN
AGREEMENT WITH THIS SCENARIO AND WILL DECREASE POPS AS WE WORK
NORTHEAST ACROSS THE FORECAST AREA.
AS FOR TODAY...DEEP CLOSED LOW OVER THE SOUTHWEST STATES WILL
CONTINUE TO PUMP MOISTURE NORTH AND EAST ACROSS THE FORECAST AREA.
ANOTHER WAVE ROUND THE BASE OF THE LOW EVIDENT IN WATER VAPOR
IMAGERY THIS MORNING. THIS WILL ROTATE UP AND INTO OUR SOUTHERN
ZONES BY THIS AFTERNOON...SPARKING ANOTHER ROUND OF STRONGER
STORMS...ALTHOUGH NOT QUITE AS STRONG AS WE SAW LAST EVENING.
PRECIPITABLE WATER VALUES STILL QUITE HIGH FOR THIS TIME OF YEAR
AND WILL CONTINUE THE FLASH FLOOD WATCH FOR SOUTHEAST UTAH...WHICH
WILL BE MORE PRONE TO QUICK AND SUDDEN RUNOFF IN OUR SLOT AND ROCK
COUNTRY. WITH THE LOW SLOW TO MOVE...CONVECTION WILL CONTINUE
THROUGH TONIGHT AND INTO THE DAY TOMORROW WITH LOCALLY HEAVY RAIN
STILL POSSIBLE OVER JUST ABOUT ANYWHERE THAT SEES CONVECTION ROLL
THROUGH. TEMPERATURES WILL BE COOL...BUT FORCING ASSOCIATED WITH
EJECTING WAVES WILL KEEP THE CONVECTION GOING.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 338 AM MDT TUE OCT 20 2015
THE LOW IS EXPECTED TO SLOWLY FILL AND LIFT NORTHEAST ACROSS
COLORADO WEDNESDAY NIGHT AND THURSDAY. THIS WILL EVENTUALLY ALLOW
FOR COLDER CONDITIONS TO PUSH IN LATE THURSDAY AND THURSDAY NIGHT.
EXPECT SNOW LEVELS TO DROP A BIT...MAYBE AS LOW AS 9K BY FRIDAY
MORNING. WILL TAKE A CLOSER LOOK AT THAT POTENTIAL LATER TODAY. AT
NOW APPEARS THAT THE WEEKEND WILL BE DRIER...WITH BOTH THE ECMWF
AND GFS BACKING OFF QPF NUMBERS SATURDAY AND SUNDAY. WITH SOME
AGREEMENT THERE...WILL STICK WITH THE BLENDED SOLUTIONS AND ALLOW
POPS TO TAIL OFF THROUGH THE LATER PERIODS. ANOTHER WAVE DOES
APPROACH BY MONDAY...BUT TIMING DIFFERENCES KEEPING CONFIDENCE
LOW WITH THAT SYSTEM. TEMPS WILL BE RUNNING NEAR TO SLIGHT BELOW
SEASONAL NORMS TO START OFF THE EXTENDED...WITH A NUDGE UP OVER
THE WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 338 AM MDT TUE OCT 20 2015
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS EASTERN
UTAH AND WESTERN COLORADO THROUGH WEDNESDAY. A FEW STORMS WILL BE
STRONG AND CAPABLE OF PRODUCING HAIL UP TO 1 INCH IN DIAMETER AND
GUSTY OUTFLOW WINDS IN EXCESS OF 45 KTS. CIGS WILL BRIEFLY DROP
BELOW MVFR THRESHOLDS AS SHOWERS MOVE THROUGH. SNOW LEVELS LOOK TO
REMAIN AOA 10K THROUGH THIS OPERATIONAL PERIOD.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...FLASH FLOOD WATCH THROUGH THIS EVENING FOR UTZ022-027>029.
&&
$$
SHORT TERM...JDC
LONG TERM...JDC
AVIATION...JDC
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1132 PM MDT MON OCT 19 2015
.UPDATE...
ISSUED AT 1128 PM MDT MON OCT 19 2015
STRONG THUNDERSTORMS CONTINUE TO RUMBLE ACROSS THE REGION THIS
EVENING WITH SEVERAL REPORTS OF SMALL TO MARGINALLY SEVERE SIZE
HAIL IN THE POPULATED AREAS. CONVECTION WILL CONTINUE ROLLING NE
OVERNIGHT AIDED BY WEAK SPEED MAX AND SHRTWV ENERGY LIFTING
THROUGH THE FORECAST AREA. WILL BE MAKING SOME MINOR ADJUSTMENTS
TO POP FIELDS FOR THE NEXT SEVERAL HOURS...WITH BLEND OF THE HRRR
AND RAP MODELS.
&&
.SHORT TERM...(TONIGHT THROUGH TUESDAY NIGHT)
ISSUED AT 310 PM MDT MON OCT 19 2015
TONIGHT THE WESTERN HALF OF THE FORECAST AREA REMAINS SANDWICHED
BETWEEN A JET COUPLET PRODUCING SOME DEFORMATION AND DIVERGENCE
ALOFT. SHOWERS AND ISOLATED THUNDERSTORMS ARE EXPECTED TO
CONTINUE THROUGH THE NIGHT IN EASTERN UTAH AND FAR WESTERN
COLORADO. LESSER SHOWER COVERAGE IS EXPECTED IN THE EASTERN HALF
OF THE FORECAST AREA WITH THUNDERSTORMS UNLIKELY. STORM MOTION
WILL BE TO THE NE AT 25-30 KTS SO LOCALIZED GUSTY WINDS ARE
POSSIBLE...AGAIN FAVORING THE WESTERN HALF. CLOUDS AND WINDS WILL
KEEP LOW TEMPERATURES MILD FOR MID OCTOBER.
THE WET CONDITIONS WILL PERSIST THROUGH TUESDAY AND TUESDAY
NIGHT AS DEEP MOISTURE REMAINS ACROSS THE AREA. BUT BY MIDDAY
THE BETTER ACTIVITY WILL HAVE SPREAD INTO THE EASTERN PORTION OF
THE FORECAST AREA AS THE UPPER LOW DROPS INTO THE DESERT
SOUTHWEST. DAYTIME HEATING WILL ENHANCE THE MARGINAL INSTABILITY
IN PLACE OVER THE ENTIRE REGION...UPSTREAM OF THE LOW.
LATE IN THE DAY AND OVERNIGHT...THE UPPER JET WILL TAKE AIM ON THE
FOUR CORNERS AS IT ROTATES AROUND THE UPPER LOW. AS A RESULT THE
FOCUS WILL SHIFT BACK TO THE SOUTHERN PORTION WHICH WILL BE UNDER
THE LEFT EXIT REGION OF THE JET.
TEMPERATURES WILL REMAIN ON THE MILD SIDE. HIGHS WILL BE NEAR TO
SLIGHTLY ABOVE NORMAL FOR THIS TIME OF YEAR. LOWS WILL BE WELL
ABOVE NORMAL IN THIS MOIST AIR MASS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 310 PM MDT MON OCT 19 2015
THE LOW MEANDERS THROUGH AZ ON WED/WED EVENING BEFORE GRADUALLY
LIFTING TO THE NORTHEAST OVERNIGHT AND ON THU. THEREFORE UNSETTLED
CONDITIONS WILL PERSIST THROUGH THU...WITH A DRYING TREND
THEREAFTER. THE MAIN TROUGH WILL BE OVERHEAD ON THU...SO COVERAGE
WILL BE MORE EGALITARIAN...EXCEPT SHOWERS WILL STILL FAVOR THE
HIGHER TERRAIN.
A SPLITTING SECONDARY WAVE WILL DROP INTO THE GREAT BASIN ON THU.
THIS ALREADY WEAK WAVE WILL WEAKEN EVEN MORE...AND WILL FORM A
TROUGH OVER WESTERN AZ ON FRI. THIS TROUGH WILL THEN EXTEND FROM
THE FOUR CORNERS THROUGH AZ FRI NIGHT. WHILE SOME SHOWERS WILL
CONTINUE OVER THE AREA...MOISTURE AND INSTABILITY DECREASE.
THEREFORE COVERAGE WILL BE MUCH LESS THAN EXPERIENCED EARLIER IN
THE WEEK.
A SHORT-LIVED...WEAK RIDGE WILL DEVELOP NORTH OF THE TROUGH...AND OVER
OUR CWA ON SAT. ADDITIONAL WAVES WILL FOLLOW...BUT THESE ARE
PROGGED TO REMAIN MOSTLY OVER THE NORTHERN TIER STATES. THEREFORE
THE DRYING TREND WILL CONTINUE THROUGH EARLY NEXT WEEK FOR OUR
FORECAST AREA.
NIGHTTIME LOWS REMAIN MILD...DAYTIME HIGHS WILL RANGE FROM 3-6
DEGREES ABOVE NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1128 PM MDT MON OCT 19 2015
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS EASTERN
UTAH AND WESTERN COLORADO THROUGH TUESDAY EVENING. A FEW STORMS
WILL BE STRONG AND CAPABLE OF PRODUCING HAIL UP TO 1 INCH IN
DIAMETER AND GUSTY OUTFLOW WINDS IN EXCESS OF 45 KTS. CIGS WILL
BRIEFLY DROP BELOW MVFR THRESHOLDS AS SHOWERS MOVE THROUGH. SNOW
LEVELS LOOK TO REMAIN AOA 10K THROUGH THIS OPERATIONAL PERIOD.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...FLASH FLOOD WATCH THROUGH TUESDAY EVENING FOR UTZ022-027>029.
&&
$$
UPDATE...JDC
SHORT TERM...JOE/EH
LONG TERM...EH
AVIATION...JDC
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
447 AM EDT TUE OCT 20 2015
.SYNOPSIS...
08Z WATER VAPOR AND H4 RAP ANALYSIS SHOW AN AMPLIFYING UPPER LEVEL
PATTERN ACROSS THE CONUS AS SIGNIFICANT ENERGY AND DEEP TROUGHING
DIG ACROSS THE INTER-MOUNTAIN WEST AND SOUTHWESTERN STATES. THESE
HEIGHT FALLS AS THEY PROGRESS EASTWARD TOWARD THE SOUTHERN PLAINS
OVER THE NEXT 24 TO 36 HOURS WILL HELP TO FURTHER AMPLIFY THE
UPPER RIDGE OVER THE GULF OF MEXICO INTO AND OVER THE SOUTHEASTERN
CONUS. THIS BUILDING UPPER RIDGE AND ASSOCIATED LARGE SCALE
SUPPRESSION WILL KEEP THE MID/UPPER LEVELS OVER OUR HEADS QUITE
DRY THE NEXT SEVERAL DAYS. THIS DRY AIR ALOFT WAS WELL SAMPLED BY
THE 00Z KTBW SOUNDING LAST EVENING...AND DO NOT EXPECT TO SEE MUCH
MOISTENING OF THIS AIRMASS THROUGH TODAY.
ALL THE MOISTURE IS TRAPPED BELOW THE SUBSIDENCE
INVERSION...GENERALLY BELOW 800MB WHERE SOME AIRMASS MOISTENING IS
OCCURRING FROM THE LOWER LEVEL WIND FLOW OFF THE ATLANTIC. THIS
EASTERLY FLOW IS BEING DRIVEN BY STRONG HIGH PRESSURE CENTERED TO
OUR NORTH ALONG THE CAROLINA COAST AND WESTERN ATLANTIC. THIS HIGH
PRESSURE IS ALSO NOT EXPECTED TO CHANGE MUCH IN ORGANIZATION OR
POSITION THROUGH TODAY.
SKIES ARE MOSTLY CLEAR ACROSS THE REGION EARLY THIS MORNING. SOME
LOWER STATOCU OFF THE ATLANTIC CAN BE SEEN IN SATELLITE IMAGERY
OVER TOWARD THE I-95 CORRIDOR OR THE STATE...HOWEVER THESE CLOUDS
ARE DISSIPATING RAPIDLY AS THEY ATTEMPT TO MOVE INLAND...AND WILL
EXPECT THIS TO CONTINUE UNTIL AT LEAST SEVERAL HOURS AFTER
SUNRISE. SEASONABLE TEMPERATURES SEEN ACROSS THE REGION EARLY THIS
MORNING...WITH MANY UPPER 50S TO LOWER 60S NORTH...AND MID TO
UPPER 60S SOUTH.
&&
.SHORT TERM (TODAY THROUGH WEDNESDAY)...
GENERALLY BENIGN AND SEASONABLE WEATHER WILL CONTINUE ACROSS THE
REGION TODAY WITH UPPER RIDGING BUILDING ALOFT...AND SURFACE HIGH
PRESSURE HOLDING IN PLACE TO OUR NORTH. THE ONLY WEATHER CONCERN
TODAY WILL BE SOME GUSTY EASTERLY WINDS DEVELOPING BY MID/LATE
MORNING...SIMILAR TO THE CONDITIONS SEEN ON MONDAY ACROSS THE
REGION. OTHER THAN THE GUSTY WINDS...LOOK FOR MOSTLY CLEAR SKIES
GIVING WAY TO A MIX OF SUN AND CLOUDS DUE TO DIURNAL MIXING OF THE
LOWER LEVEL ATLANTIC MOISTURE. WIDELY SCT AND VERY SHALLOW SPEED
CONVERGENCE SHOWERS/SPRINKLES ALONG THE FLORIDA EAST COAST WILL
QUICKLY MIGRATE INLAND AND DISSIPATE THROUGHOUT THE DAY. KEEPING
MEASURABLE RAIN CHANCES BELOW 10% EVERYWHERE...HOWEVER...A FEW
BRIEF SPRINKLES CAN NOT BE RULED OUT ACROSS INLAND AREA THIS
AFTERNOON...ESPECIALLY FOR SUMTER/POLK/HIGHLANDS COUNTIES. ANY
SHOWERS THAT MAKE IT THIS FAR INLAND FROM THE I-95 CORRIDOR WILL
BE VERY LIGHT...AND DO NOT ANTICIPATE ANY WETTING RAINS FOR ANY
PART OF OUR FORECAST AREA. TEMPERATURES WILL BE SEASONABLE WITH
LOWER 80S NORTH AND MIDDLE 80S SOUTH.
TONIGHT...EXPECT THE WINDS TO BECOME LESS GUSTY WITHIN A FEW HOURS
OF SUNSET THIS EVENING...ALONG WITH SKIES BECOME MOSTLY CLEAR.
ANY SPEED CONVERGENCE SPRINKLES SHOULD AGAIN BECOME CONFINED TO
THE I-95 CORRIDOR OF THE STATE. SO THE FORECAST OVERNIGHT WILL
LOOK FOR DRY CONDITIONS AND TEMPERATURES QUICKLY DROPPING BACK
INTO THE 60S AND LOWER 70S. LOW TEMPERATURES BY DAWN WEDNESDAY
WILL BE SIMILAR TO THIS MORNING RANGING FROM THE UPPER 50S/LOWER
60S NORTH OF THE I-4 CORRIDOR...TO THE MID/UPPER 60S FURTHER
SOUTH.
THE PATTERN DOES NOT CHANGE MUCH FOR WEDNESDAY...AND HENCE NEITHER
DOES THE FORECAST. MOSTLY CLEAR SKIES GIVE WAY TO A SCT CUMULUS
FIELD AND THE POTENTIAL FOR A FEW ISOLATED SPRINKLES OVER THE
INTERIOR FOR THE AFTERNOON. MEASURABLE RAIN CHANCES AGAIN REMAIN
BELOW 10% FOR ALL AREAS. THE HIGH PRESSURE RIDGE TO OUR NORTH WILL
REMAIN IN PLACE...BUT WEAKEN BY A FEW MILLIBARS COMPARED TO
TODAY. THE SLIGHTLY WEAKER PRESSURE GRADIENT WILL KEEP A STEADY
EASTERLY FLOW ACROSS THE PENINSULA...BUT SHOULD RESULT IN LESS
GUSTY CONDITIONS.
&&
.LONG TERM (THURSDAY THROUGH NEXT MONDAY)...
PERIOD WILL BEGIN WITH THE MAIN NORTHERN STREAM U/L FLOW EXTENDING
ACROSS THE NORTHERN U.S. AND CANADA. A CUT-OFF U/L LOW WILL BE OVER
THE SOUTHWEST U.S. IN THE SOUTHERN STREAM WITH AN U/L RIDGE OVER THE
GULF OF MEXICO AND FLORIDA. U/L ENERGY WILL DIG ALONG THE PACIFIC
WEST COAST THURSDAY AND FRIDAY WHICH WILL OPEN UP THE U/L LOW OVER
THE SOUTHWEST U.S. CARVING OUT A L/W TROUGH OVER THE INTER-MOUNTAIN
WEST AND WESTERN CANADA. THIS WILL BUILD THE DOWNSTREAM U/L RIDGE
OVER THE GULF OF MEXICO EXTENDING NORTH ALONG THE EASTERN SEABOARD.
SPLIT FLOW PATTERN WILL DEVELOP ALONG THE WEST COAST OF THE U.S. AND
CANADA SATURDAY AND SUNDAY WITH ZONAL FLOW ALONG THE CALIFORNIA
COAST...UNDER-CUTTING AN EXTENSIVE U/L RIDGE TO THE NORTH ALONG THE
WEST COAST OF CANADA THROUGH ALASKA. THE STRONG ZONAL FLOW WILL
EXTEND TO THE CENTRAL U.S. ON SUNDAY AND MONDAY WHICH WILL FLATTEN
OUT THE U/L RIDGE OVER THE GULF OF MEXICO.
AT THE SURFACE...HIGH PRESSURE OVER THE WESTERN ATLANTIC WILL BEGIN
TO SLIDE EAST OF THE AREA ON THURSDAY...HOWEVER RELATIVELY TIGHT
PRESSURE GRADIENT WILL PERSIST ACROSS THE FLORIDA PENINSULA WITH
EASTERLY BOUNDARY LAYER FLOW. REINFORCING AREA OF HIGH PRESSURE
OVER SOUTHEAST CANADA WILL BRIDGE SOUTH DOWN THE EASTERN SEABOARD
AND FLORIDA ON FRIDAY. PRESSURE GRADIENT ACROSS THE FORECAST AREA
WILL WEAKEN A BIT BUT WILL REMAIN FROM THE EAST TO NORTHEAST. THE
SURFACE HIGH WILL MOVE OVER THE WESTERN ATLANTIC SATURDAY AND
SUNDAY. GRADUAL INCREASE IN DEEP LAYER MOISTURE WILL OCCUR OVER
WEST CENTRAL AND SOUTHWEST FLORIDA LATE IN THE WEEKEND INTO EARLY
NEXT WEEK AS A TROUGH TAKES SHAPE IN THE WESTERN GULF OF MEXICO AND
U/L ENERGY MOVES ACROSS THE LOWER MISSISSIPPI VALLEY.
STRONG U/L RIDGE OVER THE REGION WEDNESDAY NIGHT THROUGH SATURDAY
WILL CONTINUE TO PRODUCE DRY CONDITIONS AND ABOVE NORMAL
TEMPERATURES ACROSS THE FORECAST AREA. AS THE U/L RIDGE BREAKS DOWN
AND HEIGHTS LOWER LATE IN THE WEEKEND INTO EARLY NEXT
WEEK...TEMPERATURES WILL COOL A FEW DEGREES BUT WILL REMAIN A COUPLE
OF DEGREES ABOVE NORMAL. INCREASING DEEP LAYER MOISTURE AND WEAK L/L
INSTABILITY WILL CREATE A SLIGHT CHANCE OF AN AFTERNOON SHOWER
SUNDAY AND MONDAY.
&&
.AVIATION...
VFR CONDITIONS CAN BE EXPECTED FOR ALL TERMINALS THROUGH THE TAF
PERIOD. AVIATION CONCERNS WILL BE LIMITED TO ELEVATED AND GUSTY
EAST TO NORTHEAST WINDS DEVELOPING THIS MORNING AND CONTINUING
THROUGH THE EARLY PORTION OF THE EVENING. WINDS WILL AGAIN BECOME
LESS GUSTY WITHIN A FEW HOURS AFTER SUNSET THIS EVENING.
&&
.MARINE...
STRONG HIGH PRESSURE TO THE NORTH OF THE REGION WILL
KEEP A TIGHT PRESSURE GRADIENT OVER THE EASTERN GULF OF MEXICO
THROUGH THE MIDDLE OF THE WEEK. ELEVATED AND GUSTY EASTERLY WINDS
ARE EXPECTED WITH PERIODS OF HAZARDOUS BOATING CONDITIONS
CONTINUING THROUGH WEDNESDAY. EASTERLY FLOW IS ANTICIPATED TO
CONTINUE THROUGH THE REMAINDER OF THE WEEK...WITH WINDS
INCREASING EACH OVERNIGHT AND EARLY MORNING PERIOD. CAUTIONARY
LEVEL WINDS CAN BE EXPECTED EACH OVERNIGHT THROUGH AT LEAST THE
EARLY PORTION OF THE WEEKEND...ESPECIALLY AWAY FROM THE IMMEDIATE
COAST.
&&
.FIRE WEATHER...
SURFACE HIGH PRESSURE HOLD TO OUR NORTH THROUGH THE MIDDLE OF THE
WEEK KEEPING A STEADY EASTERLY FLOW GOING ACROSS THE FLORIDA
PENINSULA. WINDS WILL AT TIMES BE RATHER GUSTY...LEADING TO
ELEVATED DISPERSION INDICES THIS AFTERNOON AND AGAIN WEDNESDAY
AFTERNOON. DESPITE THE HIGH DISPERSION INDICES...RELATIVE
HUMIDITY VALUES ARE EXPECTED TO GENERALLY REMAIN ABOVE CRITICAL
LEVELS AND NO RED FLAG CONDITIONS ARE CURRENTLY EXPECTED. THE
EASTERLY FLOW OFF THE ATLANTIC MAY LEAD TO A FEW ISOLATED
SPRINKLES ACROSS INLAND PORTIONS OF THE PENINSULA THE NEXT
SEVERAL AFTERNOONS...HOWEVER ANY SHOWERS WILL BE BRIEF AND
VERY LIGHT...AND WETTING RAINFALL IS NOT EXPECTED.
FOG POTENTIAL...NO SIGNIFICANT FOG IS EXPECTED FOR THE NEXT
FEW DAYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 85 69 87 70 / 0 0 0 0
FMY 86 69 88 70 / 0 0 0 0
GIF 84 66 86 68 / 10 10 10 10
SRQ 85 69 88 71 / 0 0 0 0
BKV 83 63 86 65 / 0 0 10 0
SPG 83 71 86 72 / 0 0 0 0
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...SMALL CRAFT ADVISORY UNTIL 10 AM EDT WEDNESDAY
FOR COASTAL WATERS FROM BONITA BEACH TO ENGLEWOOD FL OUT 20 NM-
COASTAL WATERS FROM ENGLEWOOD TO TARPON SPRINGS FL OUT 20 NM-
COASTAL WATERS FROM TARPON SPRINGS TO SUWANNEE RIVER FL OUT 20 NM-
WATERS FROM BONITA BEACH TO ENGLEWOOD FL OUT 20 TO 60 NM-WATERS
FROM ENGLEWOOD TO TARPON SPRINGS FL OUT 20 TO 60 NM-WATERS FROM
TARPON SPRINGS TO SUWANNEE RIVER FL OUT 20 TO 60 NM.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...14/MROCZKA
LONG TERM/DECISION SUPPORT...13/OGLESBY
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
250 AM CDT TUE OCT 20 2015
...Updated Short term and Long term discussions...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 245 AM CDT TUE OCT 20 2015
NAM, GFS, and RAP were all in good agreement with another upper
level disturbance, located just west of Baja California at 00z
Tuesday, approaching southwest Kansas early tonight. A surface
trough of low pressure will be located from southeast Colorado
into south central Nebraska by late day. Latest NAM indicating
limited low level forcing along this front and 0-6km shear will be
20 knots or less. CAPE values near the surface trough is forecast
to be less than 600 J/Kg so at this time not overly excited about
late day convection, however unable to rule out a few isolated
storms in far western Kansas early this evening. The chance for
will improve during the overnight hours as moisture and improving
upper level lift develops ahead of an upper level trough that is
forecast to cross western Kansas tonight. At this time the better
forcing will be across far western Kansas early tonight and then
shift north after midnight.
The potential for afternoon cloud cover will make temperatures a
little tricky today, however am expecting a fair amount of sun so
will based highs on 00z Wednesday 850mb temperatures. This is
close to the latest guidance of highs mainly in mid 80s.
.LONG TERM...(Wednesday THROUGH Monday)
ISSUED AT 245 AM CDT TUE OCT 20 2015
On Wednesday moisture will continue to improve in the 850mb to
700mb level as another upper level disturbance approaches from the
southwest. Better difluent flow will be present aloft, especially
late day as a surface boundary drops south into southwest Kansas.
Given this will stay close to the previous forecast with
precipitation chances increasing late day and early Wednesday
night.
The best chance for widespread precipitation still appears to
occur across western and central Kansas late Wednesday night and
Thursday given the moisture forecast across western Kansas and the
location of the upper level jet streak east of the upper low that
will be crossing the four corners region on Thursday. Also given
the expected precipitation and cloud cover will continue to favor
lows near or above guidance while undercutting highs on Thursday.
Thursday night into Friday the upper low opens up as it lifts
northeast into the northern Plains. As this upper level trough
crosses western Kansas Thursday night the precipitation chances is
expected to taper off from west to east. There will then be a
slight chance for some showers or even an isolated thunderstorm
late Friday night as a weak upper level trough crosses the central
high plains.
The weekend will be mainly dry and cool with highs mainly in the
60s Both Saturday and Sunday.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z Tuesday NIGHT)
ISSUED AT 1209 AM CDT TUE OCT 20 2015
A surface trough of low pressure will slowly slide east into
western Kansas early this morning as an upper level disturbance
moves from the Texas Panhandle to central Kansas. 00Z BUFR
soundings indicating moisture ahead of this first upper level
system will be located above 6000 ft AGL and a period of VFR
ceilings are anticipated across western Kansas between 06z and 12z
Tuesday. Southerly winds at around 15 knots will continue
overnight with a few higher gusts possible at times. These
southerly winds will decrease into the 10 to 15 knot range and
begin to gradually veer to the southwest after 12z Tuesday as the
surface trough moves into western Kansas, especially at GCK and
HYS. Mid level moisture will begin to spread into southwest Kansas
after 00z Wednesday as the next upper level trough approaches
moves northeast across eastern New Mexico.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 85 57 73 56 / 0 30 50 70
GCK 86 56 67 53 / 0 30 60 70
EHA 83 56 66 53 / 0 40 60 70
LBL 85 59 73 56 / 0 40 60 70
HYS 86 57 70 54 / 0 30 50 60
P28 83 60 77 59 / 0 20 40 60
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Burgert
LONG TERM...Burgert
AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS JACKSON KY
132 AM EDT TUE OCT 20 2015
.UPDATE...
ISSUED AT 1047 PM EDT MON OCT 19 2015
VALLEY TEMPS ARE DROPPING QUICKLY THIS EVENING...AND HAVE LOWERED
THE MIN TEMP FORECAST TO ALLOW FOR COLDER READINGS IN OUR EASTERN
VALLEYS.
UPDATE ISSUED AT 742 PM EDT MON OCT 19 2015
MADE MINOR UPDATES TO THE GRIDDED FORECAST IN LIGHT OF RECENT
OBS...BUT WITHOUT ANY SUBSTANTIVE CHANGE TO THE FORECAST.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 320 PM EDT MON OCT 19 2015
18Z SFC ANALYSIS SHOWS HIGH PRESSURE JUST EAST OF KENTUCKY WITH A
RELATIVELY LOOSE GRADIENT ACROSS EASTERN KENTUCKY...BUT TIGHTER AS
YOU GO NORTHWEST TOWARD MUCH LOWER PRESSURE. THIS HIGH HAS KEPT
THE SKIES CLEAR TODAY AND WITH PLENTY OF SUNSHINE READINGS HAVE
CLIMBED INTO THE LOW AND MID 60S. MEANWHILE...DEW POINTS HAVE
MIXED DOWN INTO THE UPPER 20S AND LOWER 30S YIELDING HUMIDITIES
DOWN IN THE 20 TO 25 PERCENT RANGE ACROSS PARTS OF EASTERN
KENTUCKY. ALTHOUGH THE HIGH IS KEEPING WINDS RELATIVELY
LIGHT...THE DEEP MIXING IS BRINGING DOWN SOME OCCASIONAL SOUTH
SOUTHWEST GUSTS TO BETWEEN 10 AND 15 MPH.
THE MODELS CONTINUE TO BE IN EXCELLENT AGREEMENT THROUGH THE SHORT
TERM AS THEY ALL DEPICT FLAT AND BROAD RIDGING SPREADING OVER THE
REGION INTO WEDNESDAY MORNING. ONLY WEAK ENERGY WILL DRIFT PAST
EASTERN KENTUCKY AMID THOSE HIGHER HEIGHTS. THE PATTERN DOES
START TO CHANGE AFTER THE SHORT TERM WITH A DEVELOPING NORTHERN
STREAM TROUGH MOVING EAST ALONG THE INTERNATIONAL BORDER INTO
WESTERN ONTARIO. AGAIN FAVORED THE HRRR AND NAM12 FOR WEATHER
DETAILS GIVEN THE MODEL AGREEMENT THROUGH WEDNESDAY MORNING.
SENSIBLE WEATHER WILL FEATURE ANOTHER CLEAR NIGHT WITH GOOD
RADIATIONAL COOLING. THIS WILL RESULT IN A FAIRLY LARGE RIDGE TO
VALLEY TEMPERATURE SPLIT. AGAIN...SOME PATCHY FOG WILL BE FOUND IN
THE VALLEYS TOWARDS DAWN. FOR TUESDAY AND TUESDAY NIGHT CONDITIONS
WILL BE SIMILAR TO THE PAST 24 HOURS WITH WARMER TEMPERATURES
GIVEN THE MODERATING HIGH DEPARTING THE AREA. ACCORDINGLY...HIGH
TEMPERATURES ON TUESDAY WILL BE ANOTHER 5 DEGREES OR SO HIGHER
THAN TODAY WITH SIMILAR LOW RH CONCERNS. WINDS WILL PICK UP A BIT
MORE...AS WELL...RUNNING FROM THE SOUTHWEST AT AROUND 10 MPH WITH
SOME HIGHER GUSTS. WILL HIGHLIGHT THIS LOW RH AND INCREASING WIND
CONCERN IN THE HWO. TEMPERATURES WILL BE A BIT MILDER TUESDAY
NIGHT WITH STILL A LARGE RIDGE AND VALLEY TEMPERATURE SPLIT
ANTICIPATED...ALONG WITH PATCHY VALLEY FOG NEAR DAWN.
AGAIN STARTED WITH THE SHORTBLEND GUIDANCE FOR THE T AND TD GRIDS
INTO TUESDAY MORNING FOLLOWED BY THE SUPERBLEND. DID MAKE SOME
SIGNIFICANT CHANGES TO THE T GRIDS TONIGHT AND TUESDAY NIGHT TO
ACCOUNT FOR THE ANTICIPATED RIDGE AND VALLEY DIFFERENCES. AS FOR
POPS...ONCE AGAIN ZEROED THEM OUT THROUGH THE SHORT TERM PERIOD...
IN LINE WITH ALL GUIDANCE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 240 PM EDT MON OCT 19 2015
HIGH PRESSURE WILL HOLD OVER KENTUCKY THROUGH MUCH OF THE
WEEK...PROVIDING A PLEASANT STRETCH OF MILD WEATHER. STILL
WATCHING FOR SOME VERY LOW RELATIVE HUMIDITIES INTO WEDNESDAY
AFTERNOON. WINDS SHOULD STAY IN THE 5 TO 10 MPH RANGE...BUT GIVEN
THE DRY CONDITIONS LEADING UP TO WEDNESDAY...ANY WIND COULD POSE
A FIRE DANGER. PLAN TO HIGHLIGHT THIS THREAT IN THE HWO.
A COLD FRONT WILL WASH OUT AS IT DROPS SOUTH INTO NORTHERN
KENTUCKY ON THURSDAY...BUT THIS FEATURE WILL REMAIN MOISTURE
STARVED AND POSE NO THREAT TO OUR WEATHER OUTSIDE A SLIGHT UPTICK
IN SKY COVER. HIGH PRESSURE WILL BUILD BACK IN BY FRIDAY AND
CONTINUE INTO SATURDAY.
ATTENTION WILL THEN TURN TO A COUPLE OF DISTURBANCES AS WE HEAD
THROUGH NEXT WEEKEND. A NORTHERN STREAM SHORTWAVE WILL PUSH EAST
ACROSS THE NORTH CENTRAL PLAINS...WITH A SOUTH WAVE CROSSING TEXAS
ON SATURDAY. WHILE ITS STILL UNCERTAIN HOW THESE TWO WAVES WILL
INTERACT AS THEY MOVE EAST...IT DOES APPEAR THESE WAVES WILL HELP
PUSH A COLD FRONT ACROSS THE AREA SATURDAY NIGHT INTO SUNDAY. GOOD
MOISTURE TRANSPORT OFF THE GULF OF MEXICO...SHOULD PROMOTE DECENT
RAIN CHANCES AS THIS BOUNDARY MOVES ACROSS KENTUCKY. MODELS ARE
COMING INTO AGREEMENT ON BEST RAIN CHANCES COMING LATE SATURDAY
NIGHT THROUGH SUNDAY. FOR THIS REASON...POPS HAVE BEEN TRENDED
UPWARDS FOR THESE TWO PERIODS. THE FRONT COULD HANG UP OVER THE
AREA INTO EARLY NEXT WEEK...KEEPING THE WEATHER SOMEWHAT
UNSETTLED. ANY RAIN WILL BE WELCOME AFTER THE EXTENDED STRETCH OF
DRY WEATHER...AND SHOULD HOPEFULLY HELP BRING A TEMPORARY END TO
ANY FIRE DANGER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 132 AM EDT TUE OCT 20 2015
FOG...POTENTIALLY DENSE...WILL AFFECT SOME DEEP VALLEY LOCATIONS
AROUND LARGE STREAMS NEAR DAWN...BUT IT IS UNLIKELY TO IMPACT TAF
SITES. OTHERWISE...VFR CONDITIONS WITH LIGHT WINDS WILL PREVAIL AS
HIGH PRESSURE REMAINS IN CONTROL.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...GREIF
LONG TERM...KAS
AVIATION...HAL/JMW
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
541 AM EDT TUE OCT 20 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 541 AM EDT TUE OCT 20 2015
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A DEEP MID LEVEL LOW
MOVING FROM HUDSON BAY INTO NRN QUEBEC. TO THE W...A TROF IS OVER
THE ROCKIES IN BOTH THE NRN AND SRN STREAMS. THE NRN STREAM
SHORTWAVE WILL BECOME RATHER VIGOROUS AS IT MOVES INTO THE UPPER
GREAT LAKES AND NRN ONTARIO WED NIGHT. AT THE SFC...COLD FRONT
ASSOCIATED WITH THE DEEP HUDSON BAY MID LEVEL LOW IS MOVING S ACROSS
UPPER MI ATTM. BRISK N TO NE WINDS HAVE DEVELOPED ACROSS LAKE
SUPERIOR BEHIND THE FRONT AND AHEAD OF SFC HIGH PRES BUILDING FROM
NRN MANITOBA INTO NRN ONTARIO. SKIES ARE MOSTLY CLEAR ACROSS THE
FCST AREA EARLY THIS MORNING. A BAND OF STRATOCU BEHIND FRONT IS
CONFINED TO THE E OF LAKE SUPERIOR SO FAR...AND A BKN NARROW BAND OF
MID LEVEL CLOUDS PRODUCING SOME RADAR RETURNS IS LURKING JUST S AND
SW OF MENOMINEE.
INITIALLY TODAY...THERE IS SOME CONCERN THAT A FEW -SHRA COULD BRUSH
THE FAR SCNTRL FCST AREA. PER LATEST RAP...LINGERING STEEP MID LEVEL
LAPSE RATES AND CONVERGENCE OF 850MB FLOW APPEAR TO BE AIDING THE
MID CLOUD/RADAR RETURNS CURRENTLY S AND SW OF MENOMINEE. HRRR RUNS
OVERNIGHT HAVE CONSITENTLY INDICATED THAT THERE WILL BE SOME
NORTHWARD DEVELOPMENT OF -SHRA/SPRINKLES INTO MENOMINEE COUNTY THIS
MORNING/EARLY AFTN. WHILE THERE IS STILL DRY AIR TO OVERCOME IN THE
LOWER LEVELS PER 00Z KGRB SOUNDING...HAVE INTRODUCED ISOLD -SHRA FOR
MENOMINEE COUNTY THIS MORNING BASED ON INCREASING RADAR
REFLECTIVITIES. OTHERWISE...A COOL NE FLOW LOCKS IN TODAY AS HIGH
PRES BUILDS SE ACROSS NRN ONTARIO. AT THIS POINT...WITH POST FRONTAL
STRATOCU REMAINING E OF LAKE SUPERIOR SO FAR AND MOVING SSE...IT
DOES NOT APPEAR THAT A BKN-OVC LOWER CLOUD DECK WILL DEVELOP IN THE
UPSLOPE AREAS TODAY. MAY SEE SOME SCT STRATOCU. OTHERWISE...AFTER A
GENERALLY MOSTLY SUNNY START...HIGH CLOUDS WILL BE ON THE INCREASE
FROM THE W AND SW. OBVIOUSLY WITH THE PASSAGE OF COLD FRONT AND NE
WINDS TODAY...IT WILL BE COOLER TODAY THAN YESTERDAY. EXPECT HIGHS
GENERALLY FROM THE UPPER 40S OVER THE HIGHER TERRAIN OF THE KEWEENAW
AND NCNTRL TO THE LOW/MID 50S ELSEWHERE.
AS SHORTWAVE ENERGY MOVES ACROSS THE NRN PLAINS/SCNTRL CANADA
TONIGHT...850MB WAA DEVELOPS ACROSS THE AREA. HOWEVER...
ISENTROPICALLY...MODELS GENERALLY SUGGEST BETTER MOIST ASCENT TO THE
SE OF THE FCST AREA. MEANWHILE...BEST DEEP LAYER FORCING ASSOCIATED
WITH APPROACHING SHORTWAVE ENERGY IS TO THE NW OF THE FCST AREA. AS
A RESULT...IT APPEARS THE 2 MAIN AREAS OF DEVELOPING PCPN WILL SPLIT
THE FCST AREA TONIGHT...AND THAT IS EXACTLY WHAT THE PCPN FIELDS
FROM THE ALL THE AVBL OPERATIONAL MODELS SHOW. HAVE THUS CUT BACK ON
POPS TONIGHT TO SCHC WITH THE LOWEST POPS ACROSS THE CNTRL FCST
AREA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 445 AM EDT TUE OCT 20 2015
NEAR TO SLIGHTLY ABOVE NORMAL TEMPERATURES THROUGH SATURDAY...THEN
COOLER AIR RETURNS. A PERIOD OF GUSTY WINDS CAN BE EXPECTED
WEDNESDAY AFTERNOON AND EVENING OVER THE KEWEENAW PENINSULA AND
ALONG LAKE SUPERIOR.
WEDNESDAY AND WEDNESDAY NIGHT...A SURFACE LOW AND UPPER LEVEL 500MB
SHORTWAVE STRETCHING FROM MANITOBA...SOUTHWARD INTO MN WILL BEGIN TO
SHIFT EASTWARD TOWARD UPPER PENINSULA. AS THE LOW CENTER SLIDES
ACROSS LAKE SUPERIOR THROUGH THE DAY AND THE ASSOCIATED COLD FRONT
SLIDES THROUGH THE AREA...EXPECT WIDESPREAD RAIN SHOWERS TO DEVELOP.
THE BEST FORCING WILL REMAIN CLOSER TO THE LOW
CENTER...HOWEVER...THERE WILL BE ENOUGH FORCING ACROSS THE REST OF
THE AREA...AS SHOWN BY ANALYZING 1000-500MB RH ALONG WITH DEEP LAYER
QCONV...TO CREATE WIDESPREAD RAIN SHOWERS. THIS LOW WILL QUICKLY
DEPART TO THE EAST OF THE AREA WEDNESDAY EVENING AS IT RAPIDLY
INTENSIFIES AND MUCH DRIER DEEP LAYER AIR SURGES IN BEHIND IT ON
WESTERLY TO NORTHWESTERLY WINDS. THIS WILL ALLOW FOR A VERY QUICK
END TO THE RAIN SHOWERS FROM WEST TO EAST THROUGH THE EVENING HOURS.
ADDITIONALLY...BEHIND THE COLD FRONT...THE PRESSURE GRADIENT WILL
INCREASE BETWEEN THE DEPARTING LOW AND THE HIGH PRESSURE QUICKLY
BUILDING IN BEHIND IT WEDNESDAY NIGHT. THIS WILL ALLOW FOR GUSTY
WEST TO NORTHWESTERLY WINDS. COULD SEE GUSTS UP TO 30 TO 40 MPH OVER
THE KEWEENAW PENINSULA AND NEAR LAKE SUPERIOR IN THE LATE AFTERNOON
AND EVENING HOURS...WITH A BRIEF PERIOD OF GALES POSSIBLE OVER LAKE
SUPERIOR. THIS WILL BE ESPECIALLY TRUE IF STRONGER WINDS MIX DOWN TO
THE SURFACE. WINDS AT 925MB TO 900MB ARE RIGHT AROUND 35 TO 40
KNOTS...AGAIN WITH CAA...IT WILL BE VERY POSSIBLE FOR THESE STRONGER
WINDS TO MIX DOWN...ESPECIALLY OVER THE KEWEENAW PENINSULA AND LAKE
SUPERIOR. THE SHOWERS COULD LINGER A BIT LONGER OVER THE EASTERN
U.P. DUE TO THE PROXIMITY TO THE DEPARTING LOW ALONG WITH CAA INTO
THE AREA. 850MB TEMPERATURES ARE PROGGED TO DROP TO NEAR
-2C LATE WEDNESDAY NIGHT...WITH THE WEST TO NORTHWEST FLOW...WHICH
WILL AT A MINIMUM KEEP THE POTENTIAL FOR LAKE EFFECT CLOUD COVER
OVER THE EAST HALF NEAR LAKE SUPERIOR.
THURSDAY THROUGH FRIDAY...THE GENERAL TREND IS FOR A SURFACE RIDGE
AND ASSOCIATED UPPER LEVEL RIDGE TO QUICKLY BUILD FROM THE NORTHERN
PLAINS AND CANADA INTO THE UPPER GREAT LAKES THURSDAY AND LINGER
THROUGH MOST OF THE DAY FRIDAY. THIS WILL KEEP MAINLY DRY CONDITIONS
IN THE FORECAST. THERE MAY BE SOME LINGERING LOW CLOUDS AS 850MB
TEMPS SLOWLY START TO REBOUND OVER THE EAST AND THE LOW CONTINUES TO
DEPART THROUGH QUEBEC THROUGH THURSDAY AFTERNOON. OTHERWISE...FOR
THE REST OF THE AREA SKIES WILL BE PARTLY CLOUDY THROUGH FRIDAY
MORNING. FRIDAY AFTERNOON...THE NEXT UPPER LEVEL TROUGH AND SURFACE
LOW SLIDING ACROSS SOUTHERN CANADA...ALONG WITH ASSOCIATED COLD
FRONT...WILL APPROACH THE REGION FROM THE WEST. THIS WILL ALLOW FOR
INCREASING CLOUDS FROM THE WEST...HOWEVER...MOST OF THE AREA SHOULD
REMAIN DRY FOR DURING THE DAY FRIDAY.
FRIDAY NIGHT SATURDAY...THE AFOREMENTIONED LOW PRESSURE SYSTEM AND
ASSOCIATED COLD FRONT WILL CONTINUE TO SLIDE EAST ACROSS THE AREA.
MODELS ARE BECOMING MORE SETTLED ON A SOLUTION WITH THE SURFACE LOW
SLIDING FROM NORTHERN MN FRIDAY NIGHT TO NEAR JAMES BAY BY SATURDAY
EVENING. THIS WILL DRAG A COLD FRONT THROUGH THE AREA THROUGH THE
DAY SATURDAY. THERE WILL BE PLENTY OF MOISTURE AND FORCING ALONG THE
FRONT TO ALLOW FOR A RAINY SATURDAY ACROSS MUCH OF THE U.P. ANOTHER
THING TO NOTE...EVEN THOUGH THIS IS STILL SEVERAL DAYS OUT...IS THAT
BOTH THE GFS/EC SHOW THE UPPER LEVEL SHORTWAVE ASSOCIATED WITH THE
TROUGH DIGGING MUCH FARTHER SOUTH THAN THE EARLIER MODEL RUNS. THIS
ACTS TO INTENSIFY THE SURFACE LOW AS THE 500MB SHORTWAVE IS
STAGGERED BACK TO THE WEST OF THE SURFACE LOW. IF THE LOW DOES
INTENSIFY AS PROGGED...WE COULD BE LOOKING AT ANOTHER PERIOD OF
GUSTY WINDS ACROSS THE AREA ON CAA...DUE TO FAIRLY STRONG PRESSURE
GRADIENT ALONG WITH MIXING OF FAIRLY STRONG WINDS DOWN FROM 850MB.
AGAIN THIS IS A WAYS OUT...BUT DEFINITELY SOMETHING TO KEEP IN MIND.
SATURDAY NIGHT THROUGH THE EXTENDED...THE GFS/EC BOTH AGREE ON A
DECENT RIDGE BUILDING OVER THE WESTERN CONUS WITH BROAD TROUGHING
SETTLING IN OVER THE EASTERN U.S. THROUGH THIS TIME PERIOD...850MB
TEMPS ARE PROGGED TO DROP INTO THE -4C TO -8C RANGE WHICH WILL
SUPPORT LAKE EFFECT CLOUD COVER AND LAKE EFFECT RAIN DURING THE DAY
AND POSSIBLY LAKE EFFECT SNOW SUNDAY NIGHT AS THE COLDER AIR SLIDES
INTO THE AREA. AT THE TIME BEING THE BEST CHANCE FOR LAKE EFFECT
PRECIPITATION WOULD BE FOR WEST TO WEST NORTHWEST FAVORED AREAS.
AGAIN THIS IS ABOUT A WEEK OUT SO THINGS CAN DEFINITELY CHANGE AND
THE EXACT DETAILS WILL STILL NEED TO BE IRONED OUT AS CONFIDENCE IN
THE MODELS INCREASES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 121 AM EDT TUE OCT 20 2015
VFR CONDITIONS WILL CONTINUE AT KIWD/KCMX/KSAW FOR MUCH IF NOT ALL
OF THIS FCST PERIOD AS LOW LEVELS REMAIN DRY. A COLD FRONT WILL DROP
ACROSS THE AREA DURING THE NIGHT. THE SHIFT TO AN UPSLOPE N TO NE
WIND BEHIND FRONT MAY RESULT IN SCT-BKN MVFR CLOUDS THIS
MORNING...MAINLY OVER CENTRAL UPPER MI. LOW LEVEL MOISTURE WILL
INCREASE THIS EVENING AS WINDS VEER TO THE ESE...RESULTING IN MVFR
CIGS AT SAW BY LATE EVENING AND CIGS LOWERING TO NEAR MVFR AT CMX
AND IWD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 541 AM EDT TUE OCT 20 2015
HIGH PRES BUILDING SE ACROSS NRN ONTARIO WILL LEAD TO BRISK NE WINDS
IN THE 15-30KT RANGE ACROSS LAKE SUPERIOR TODAY. WINDS WILL BE
STRONGEST OVER WESTERN LAKE SUPERIOR WHERE THE TERRAIN WILL FUNNEL
AND ENHANCE THE FLOW. WINDS WILL THEN VEER TO THE E-SE TONIGHT/WED
MORNING AS HIGH PRES MOVES TO QUEBEC AND A LOW PRES TROF APPROACHES.
THE STRONGER SE WINDS UP TO 30KT ARE MOST LIKELY OVER THE E HALF OF
THE LAKE ON WED. A LOW PRES CENTER WILL DEVELOP ALONG THE TROF AND
PASS JUST N OF LAKE SUPERIOR WED AFTN. AS THIS OCCURS...A FAVORABLY
ALIGNED PRES RISE/FALL COUPLET WILL GIVE AN ISALLOBARIC BOOST TO THE
WESTERLY WINDS IN THE WAKE OF COLD FROPA. RESULT SHOULD BE A FEW HRS
OF SOME GALE FORCE GUSTS AROUND THE W SIDE OF THE KEWEENAW LATE WED
AFTN/EVENING AND THEN OVER THE ERN PART OF THE LAKE WED EVENING. FOR
NOW...HELD OFF ON A GALE WATCH GIVEN THIS NEW MODEL TREND FOR
STRONGER WINDS. WINDS WILL SHIFT NW WED NIGHT THEN DIMINISH THU AS
HIGH PRES BUILDS INTO THE UPPER GREAT LAKES. WINDS WILL THEN BE ON
THE INCREASE FRI/SAT AS ANOTHER LOW PRES TROF SWEEPS THRU THE UPPER
GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KEC
AVIATION...JLB
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
232 AM PDT TUE OCT 20 2015
.SYNOPSIS...A LOW PRESSURE SYSTEM WILL BECOME CENTERED NEAR YUMA
ARIZONA TODAY AND BRING SHOWERS AND ISOLATED THUNDERSTORMS THROUGH
THE MIDDLE OF THE WEEK...MAINLY TO NORTHWEST ARIZONA AND NEARBY
AREAS OF SOUTHEAST NEVADA AND CALIFORNIA. SLIGHTLY BELOW NORMAL
TEMPERATURES CAN BE EXPECTED THIS WEEK ALONG WITH NORTH BREEZES
TUESDAY AND WEDNESDAY.
&&
.SHORT TERM...TODAY THROUGH THURSDAY NIGHT.
NOW...A VIGOROUS SHORTWAVE HAS ROUNDED THE BASE OF THE LONGWAVE
TROUGH DRAPED ACROSS THE WESTERN CONUS. THIS HAS RESULTED IN AN AREA
OF UPWARD FORCING AND CONVECTION ACROSS WESTERN ARIZONA. DISCRETE
SUPERCELLS WERE NOTED OVER YAVAPAI COUNTY BETWEEN 06Z-07Z WHICH THEN
MOVED INTO SOUTHEASTERN MOHAVE COUNTY WHERE THEY WEAKENED DUE TO
LIMITED INSTABILITY. STILL...MODERATE CONVECTION CONTINUE ACROSS THE
EASTERN HALF OF THE COUNTY.
TODAY...LAST SEVERAL RUNS OF THE HRRR HAVE INDICATED THE
DEVELOPMENT OF AN AREA OF SHOWERS WITH EMBEDDED STORMS OR EVEN A
MESOSCALE CONVECTIVE VORTEX (MCV) OVER SOUTHERN MOHAVE COUNTY
BETWEEN 12Z-15Z THIS MORNING. THIS ACTIVITY IS THEN FORECAST TO MOVE
NORTH-NORTHWEST THROUGH MID-DAY BEFORE WEAKENING. THIS WOULD THEN BE
FOLLOWED BY THE DEVELOPMENT OF DIURNALLY DRIVEN STORMS ALONG AND
SOUTH OF THE I-15 CORRIDOR. YESTERDAY`S GUIDANCE INDICATED THE
POTENTIAL FOR A PUSH OF COLD POOL DRIVEN CONVECTION WESTWARD OUT OF
MOHAVE COUNTY THIS EVENING...HOWEVER THE MOST RECENT GUIDANCE HAS
BACKED OFF ON THAT IDEA...DISSIPATING CONVECTION AFTER SUNSET. HAVE
HELD ON TO A SLIGHT CHANCE OF CONVECTION OVERNIGHT FROM LAS VEGAS
EAST...BUT COVERAGE IS EXPECTED TO BE VERY ISOLATED. OUTSIDE OF
CONVECTION...GUSTY NORTH WINDS ARE EXPECTED FROM THE COLORADO RIVER
VALLEY WEST IN THE AS ANOTHER AS SHORTWAVES REINFORCE THE GRADIENT
ACROSS THE REGION.
WEDNESDAY...CONVECTION IS EXPECTED TO BECOME CONFINED TO MOHAVE
COUNTY...AND WILL LARGELY BE DIURNALLY DRIVEN DURING THE AFTERNOON.
GUSTY NORTH WINDS WILL CONTINUE FOR MOST AREAS IN THE FORECAST AREA.
THURSDAY...CONVECTION CHANCES CONTINUE TO DECREASE...AND WILL BE
LIMITED TO NORTHERN MOHAVE AND EASTERN LINCOLN COUNTIES. WINDS
EXPECTED TO DIMINISH BY THURSDAY.
TEMPERATURES WILL REMAIN SLIGHTLY BELOW NORMAL...BUT WITH A SLOW
WARMING TREND THROUGH THE SHORT TERM PERIOD.
.LONG TERM...FRIDAY THROUGH MONDAY.
DRY CONDITIONS WITH NORTHWEST TO QUASI-ZONAL FLOW ARE EXPECTED
ACROSS THE AREA THROUGH THE MAJORITY OF THE LONG TERM PERIOD.
EMBEDDED SHORTWAVES WILL BRING OCCASIONALLY BREEZY CONDITIONS TO THE
REGION THROUGH THE WEEKEND. TEMPERATURES WILL REMAIN NEAR TO
SLIGHTLY BELOW NORMAL.
&&
.AVIATION...FOR MCCARRAN...LIGHT AND VARIABLE WINDS WILL BEGIN TO
FAVOR A NORTHWEST AND THEN NORTH DIRECTION THROUGH THE MORNING HOURS
AS SPEEDS INCREASE TO AROUND 8-12 KTS. OCCASIONAL GUSTS WILL BE
POSSIBLE. SLIGHT CHANCE OF SHRA OR POSSIBLY AND ISOLATED TS THIS
AFTERNOON/EVENING...HOWEVER CHANCES ARE TOO LOW TO MENTION IN THE
12Z TAF. CIGS GENERALLY EXPECTED TO REMAIN AOA 8K FEET. WINDS ARE
EXPECTED TO CONTINUE TO FAVOR A NORTHERLY DIRECTION THROUGH
WEDNESDAY.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...SHRA/TSRA THIS MORNING OVER MOHAVE COUNTY. EXPECT AT
LEAST SHRA AND POSSIBLY TS ACTIVITY TO SPREAD NORTH AND
EAST...THROUGH THE MORNING. DRY CONDITIONS EXPECTED WEST OF A LINE
FROM KELY-KDRA-KNXP LINE. WINDS EXPECTED TO FAVOR A NORTH DIRECTION
ACROSS MOST OF THE REGION TODAY...WITH SPEEDS 10-20 KTS AND GUSTS
20-30 KTS. SHRA/TSRA ACTIVITY WILL BE CONFINED MAINLY TO MOHAVE
COUNTY WEDNESDAY...GUSTY NORTH WINDS WILL CONTINUE.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION IS NOT EXPECTED
TODAY. HOWEVER...SPOTTERS ARE ENCOURAGED TO REPORT ACCORDING TO
STANDARD OPERATING PROCEDURES.
&&
$$
WOLCOTT
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
111 AM EDT TUE OCT 20 2015
.SYNOPSIS...
HIGH PRESSURE OVER THE CAROLINAS WILL SLIP OFFSHORE WEDNESDAY AND
THURSDAY WITH WARMING TEMPERATURES EXPECTED. A BACKDOOR COLD FRONT
WILL MOVE ACROSS THE AREA FRIDAY. ANOTHER COLD FRONT MAY MOVE
ACROSS THE AREA ON MONDAY...BRINGING A SMALL CHANCE FOR SHOWERS.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 115 AM TUESDAY...CLEAR AND COLD REMAINS THE FORECAST FOR
OVERNIGHT. TEMPERATURES AND DEWPOINTS OVERALL HIGHER THAN AT THIS
POINT LAST NIGHT BUT WE STILL HAVE PLENTY OF COOLING TO GO. MAY
RE-EVALUATE FROST ADVISORY AS NIGHT GOES ON. PREVIOUS DISCUSSION
FOLLOWS:
CANADIAN HIGH PRESSURE HAS SETTLED OVER THE COASTAL PLAIN THIS
EVENING EXTENDING FROM NORFOLK VA TO AUGUSTA GA. THIS HIGH SHOULD
MOVE VERY LITTLE THROUGH THE NIGHT. THE BROAD AREA OF WEAK
PRESSURE GRADIENT WITHIN THE HIGH WILL SUPPORT CALM WINDS AND
EXCELLENT RADIATIONAL COOLING TONIGHT. FORECAST LOWS ARE AT OR
BELOW THE LOWER END OF THE MOS GUIDANCE ENVELOPE AT ALL SITES. OUR
LOCAL RADIATIONAL COOLING TOOL SHOWS THE "POCOSIN" COLD SPOTS
SHOULD RUN A GOOD 8 DEGREES COLDER THAN NEARBY AREAS TONIGHT WITH
LOWS AROUND 30 POSSIBLE IN THE GREEN SWAMP...BLADEN LAKES STATE
FOREST...AND THE ANGOLA BAY GAMELAND ON THE PENDER-DUPLIN COUNTY
LINE.
IN THE UPPER LEVELS A LOW-AMPLITUDE LONGWAVE RIDGE COVERS MUCH OF
THE CENTRAL AND EASTERN PORTIONS OF THE NATION. A SUBTLE 500 MB
SHORTWAVE IS ACTUALLY TRAVERSING THE CAROLINAS NOW BUT WILL HAVE
NO IMPACT ON SENSIBLE WEATHER AT THE SURFACE. AS THE 850 MB HIGH
SCOOTS OFF THE COAST LATE TONIGHT WINDS AT THAT LEVEL SHOULD TURN
EASTERLY. THIS WILL BEGIN TO ADVECT ATLANTIC MOISTURE BACK TOWARD
THE COAST...BUT THIS PROCESS APPEARS IT WILL PROCEED QUITE SLOWLY
AND I HAVE DELAYED ANY INCREASE IN CLOUD COVER UNTIL AFTER
DAYBREAK TUESDAY.
NO CHANGES HAVE BEEN MADE TO THE FROST ADVISORY ALREADY ISSUED FOR
MUCH OF THE EASTERN CAROLINAS INLAND FROM THE COAST. DEWPOINTS
HAVE RISEN INTO THE MID TO UPPER 30S AT MANY SITES SINCE SUNSET.
WHILE THIS IS A PAPER-THIN LAYER OF MOISTURE LIKELY ONLY EXTENDING
ONE OR TWO HUNDRED FEET VERTICALLY...IT MAY HAVE THE INTERESTING
EFFECT OF CREATING DEW ON ELEVATED OBJECTS LATE THIS EVENING
WHICH WILL THEN FREEZE LATE TONIGHT AS AIR TEMPERATURES FALL TO
33-36. YOU MIGHT WANT TO PLAN ON SPENDING A FEW EXTRA MINUTES TO
SCRAPE THROUGH THIS LAYER OF ICE ON YOUR WINDSHIELD IN THE
MORNING.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 300 PM MONDAY...TEMPS WILL MODERATE CONSIDERABLY THROUGH
THE PERIOD. THE CENTER OF THE CHILLY AIRMASS WILL SHIFT OFFSHORE
DURING TUE. THE HIGH WILL RIDGE BACK ACROSS THE CAROLINAS...BUT
WITH THE AXIS N OF THE FORECAST AREA...WINDS WILL BECOME MORE
EASTERLY WITH TIME. THE RESULT WILL BE HIGHER TEMPS AND HIGHER
MOISTURE CONTENT WHICH WILL INCREASE DAYTIME RELATIVE HUMIDITY
VALUES. A WEAK COASTAL TROUGH MAY LINGER OFFSHORE OF THE CAROLINAS
THROUGH THE PERIOD. WILL KEEP THE ASSOCIATED PRECIPITATION
OFFSHORE FOR NOW...BUT SOME OF THE MODELS ARE HINTING AT SOME
SPOTTY AND LIGHT COASTAL SHOWERS DURING THE PERIOD. A DEEP
EASTERLY FLOW WILL ENVELOP THE AREA WHICH WILL ALLOW PRECIPITABLE
WATER VALUES TO RISE TO NEAR AN INCH ALONG THE COAST TUE AND
THROUGHOUT ON WED. EXPECT CLEAR SKIES WILL BECOME PARTLY CLOUDY AT
THE COAST TUE AND THEN THROUGHOUT ON WED.
HIGHS TUE WILL BE NEAR 70...MID 70S ON WED. LOWS TUE NIGHT WILL BE
IN THE MID AND UPPER 40S...LOWER 50S AT THE COAST. LOWS WED NIGHT
WILL BE IN THE LOWER TO MID 50S...UPPER 50S TO NEAR 60 ALONG THE
COAST.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 300 PM MONDAY...MID LEVEL RIDGING WILL PERSIST ACROSS THE
GULF OF MEXICO THURSDAY THROUGH SATURDAY AS LOW PRESSURE CONTINUES
TO WOBBLE ACROSS THE SOUTHWEST. THE BRIEF EXTENSION OF THE RIDGE
INTO THE GREAT LAKES AREA PUSHES A BACKDOOR FRONT ACROSS THE AREA
FRIDAY. THE DRY FRONT WILL PUSH BACK TEMPERATURES FOR SATURDAY.
THE REGION WILL SEE A RATHER QUICK REBOUND SUNDAY AND MONDAY AS
THE GULF RIDGE GETS WORKED OVER SUFFICIENTLY TO ALLOW THE NOW OPEN
WAVE...PREVIOUS SOUTHWEST SYSTEM TO MOVE ACROSS QUICKLY. THE
ATTENDANT FRONT SHOULD ARRIVE SOMETIME MONDAY. MOISTURE IS LIMITED
WITH THE FRONT BUT WILL MAINTAIN A SLIGHT CHANCE POP. MEDIUM RANGE
GUIDANCE HINTING AT A BETTER CHANCE OF RAIN MAYBE TOWARD THE
MIDDLE OF NEXT WEEK. OVERALL TEMPERATURE TRENDS REMAIN INTACT WITH
WARM READINGS THURSDAY FALLING BACK BRIEFLY SATURDAY THEN THE
AFOREMENTIONED RECOVERY.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 06Z...HIGH PRESSURE WILL REMAIN IN CONTROL THROUGH THE FORECAST
PERIOD. EXCELLENT RADIATIONAL COOLING CONDITIONS TONIGHT...WITH
DECOUPLING EXPECTED AT ALL SITES WITH CALM OR NEAR CALM WINDS. MOISTURE
PROFILES DO NOT SUPPORT FOG...HOWEVER THERE COULD BE SOME SHALLOW
GROUND FOG IN LOW SPOTS. A WEAK TROUGH OFFSHORE COULD PRODUCE SOME
CU/STRATA CU AFTER DAYBREAK ALONG THE COAST. LIGHT NORTHEAST FLOW
IS EXPECTED ON TUESDAY.
EXTENDED OUTLOOK...THERE IS A SMALL CHANCE WED/THU THAT
A WEAK TROUGH WILL SPREAD LIGHT SHOWERS ONSHORE AND AFFECT THE
COASTAL TERMINALS. OTHERWISE HIGH PRESSURE AND VFR CONDITIONS
THROUGH SATURDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 115 AM TUESDAY...LATEST OBS SHOW 2 TO 3 FT SEAS WITH LIGHT
NORTHERLY WINDS. NO CHANGES MADE TO THE FORECAST WITH THE LATEST
UPDATE. DISCUSSION FROM 730 PM FOLLOWS:
1031 MB CANADIAN HIGH PRESSURE EXTENDS FROM THE HAMPTON ROADS
AREA SOUTHWESTWARD INTO CENTRAL SOUTH CAROLINA. THIS WILL MAINTAIN
A NORTH-NORTHEASTERLY WIND ACROSS THE WATERS TONIGHT. LATEST
MODELS HAVE SOME DIFFERENCES WITH FORECAST WIND SPEEDS...ALTHOUGH
MOST ARE TIGHTLY CLUSTERED WITH WINDS IN THE 12-16 KNOT RANGE
OVERNIGHT. THE 21Z RUC WAS NOT USED SINCE ITS OVERNIGHT WINDS WERE
MUCH LIGHTER COMPARED TO OTHER MODELS. BUOY REPORTS AT 6 PM SHOWED
SEAS HAVE DECAYED AWAY TO 2-4 FEET INSIDE 20 MILES OF SHORE...WITH
ANY 4-FOOT SEAS LIKELY CONFINED TO AREAS NEAR FRYING PAN SHOALS
AND CAPE ROMAIN. SPECTRAL WAVE DATA FROM THE FRYING PAN SHOALS
BUOY SHOWS THE BULK OF THE WAVE ENERGY IS AROUND 6 SECONDS PERIOD.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 PM MONDAY...HIGH PRESSURE WILL MOVE OFFSHORE DURING TUE
AND THEN RIDGE BACK ACROSS THE AREA THROUGH THE REMAINDER OF THE
PERIOD. A WEAK COASTAL TROUGH MAY LINGER NEAR THE WATERS THROUGH THE
PERIOD. THIS SCENARIO WILL RESULT IN NE WINDS TUE VEERING TO A MORE
ENE TO E DIRECTION TUE NIGHT WITH A SIMILAR DIRECTION THROUGH THE
REMAINDER OF THE PERIOD. WIND SPEEDS WILL BE 10 TO 15 KT OR LESS.
SEAS WILL BE 2 TO 3 FT...WITH SOME 4 FT SEAS ACROSS PORTIONS OF THE
OUTERMOST WATERS.
LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 300 PM MONDAY...ESSENTIALLY LIGHT AND VARIABLE WIND FIELDS
THURSDAY AS WEAKENING HIGH PRESSURE SITS OVERHEAD. A BACKDOOR FRONT
MOVES ACROSS FRIDAY WITH ANOTHER PERIOD OF WINDS FROM THE NORTH
DEVELOPING. BY FRIDAY AFTERNOON WE SHOULD SEE A NORTHEAST FLOW OF 10-
15 KNOTS. THIS SHOULD CONTINUE THROUGH SUNDAY MORNING. THERE COULD
BE A FEW HOURS OF 15-20 KNOTS FRIDAY NIGHT DUE TO AN EMBEDDED SURGE.
SEAS ARE MOSTLY 2-4 FEET WITH A FEW FIVE FOOTERS DEVELOPING WITH THE
SURGE.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...FROST ADVISORY UNTIL 9 AM EDT THIS MORNING FOR SCZ017-023-024-
032-033-039-053.
NC...FROST ADVISORY UNTIL 9 AM EDT THIS MORNING FOR NCZ087-096-099-
105-109.
MARINE...NONE.
&&
$$
SYNOPSIS...RJD
NEAR TERM...REK/TRA/JDW
SHORT TERM...RJD
LONG TERM...99
AVIATION...REK/DL
MARINE...99/REK/RJD/TRA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1250 AM CDT TUE OCT 20 2015
.UPDATE...
ISSUED AT 1239 AM CDT TUE OCT 20 2015
NO MAJOR CHANCES WERE NEEDED FOR THIS UPDATE. A BAND OF LIGHT RAIN
CONTINUES TO MOVE NORTH NORTHEAST ACROSS THE SOUTHWESTERN PART OF
THE STATE. CONTINUED USING A TIME LAGGED ENSEMBLE OF HRRR
ITERATIONS...MOST CURRENTLY THROUGH ITS 04 UTC RUN...FOR
PRECIPITATION TRENDS...AS IT SEEMS TO BE PICKING UP LATEST RADAR
OBSERVATIONS WELL.
UPDATE ISSUED AT 927 PM CDT MON OCT 19 2015
THE FORECAST FOR THE REMAINDER OF THE NIGHT REMAINS ON TRACK AND
BLENDED TO A TIME LAGGED ENSEMBLE OF HRRR ITERATIONS THROUGH ITS
01 UTC RUN. THE BOWMAN ARB RADAR THROUGH 0220 UTC IS SHOWING THE
FIRST FEW RAIN SHOWERS CROSSING THE BORDER INTO SOUTHWEST NORTH
DAKOTA IN ASSOCIATION WITH THE SHORTWAVE NOW ACROSS SOUTHEAST
MONTANA.
UPDATE ISSUED AT 637 PM CDT MON OCT 19 2015
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE AS LIGHT RAIN
REMAINS LIKELY ACROSS THE WEST AND NORTH CENTRAL LATE TONIGHT INTO
TUESDAY MORNING ASSOCIATED WITH THE SHORTWAVE ACROSS NORTHEAST
WYOMING AS OF 23 UTC THAT WILL CONTINUE TO PROPAGATE NORTHEAST
THROUGH THE EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 325 PM CDT MON OCT 19 2015
MINIMAL THUNDERSTORM CHANCES IN THE FAR SOUTHWEST HIGHLIGHT THE
SHORT TERM PERIOD.
CURRENTLY...SURFACE HIGH PRESSURE IS SITUATED OVER SOUTHEAST
SASKATCHEWAN INTO WESTERN NORTH DAKOTA...WITH A NORTHEAST SURFACE
FLOW OVER THE EASTERN DAKOTAS...TRANSITIONING INTO A SOUTHEAST FLOW
OVER EASTERN MONTANA. HIGH CLOUDS WERE BEGINNING TO ENCROACH UPON
WESTERN NORTH DAKOTA AS ENERGY WITHIN AN ELONGATED UPPER LEVEL
TROUGH OVER THE WESTERN U.S. APPROACHES THE NORTHERN PLAINS.
TONIGHT...UPPER LEVEL RIDGING CURRENTLY OVER THE WESTERN AND CENTRAL
DAKOTAS WILL BREAK DOWN WITH LEAD SHORTWAVE ENERGY PROPAGATING
INTO THE NORTHERN PLAINS. MESOSCALE MODELS ARE IN GOOD AGREEMENT
IN BRINGING A BAND OF SHOWERS NORTHEAST ACROSS THE FORECAST AREA
TONIGHT. ENTERING THE FAR SOUTHWEST AROUND 02-04 UTC AND LIFTING
INTO THE FAR NORTHERN TIER COUNTIES BY AROUND 12 UTC TUESDAY. THE
INSTABILITY ALOFT IS NOT VERY IMPRESSIVE...BUT A FEW RUMBLES OF
THUNDER MAY BE POSSIBLE OVER THE FAR SOUTHWEST LATE THIS EVENING
INTO THE EARLY OVERNIGHT HOURS...CLOSEST TO THE UPPER LEVEL
SUPPORT. THUS WILL KEEP A MENTION OF THUNDER FAR SOUTHWEST.
TUESDAY...THE AFOREMENTIONED ELONGATED UPPER TROUGH SPLITS WITH THE
NORTHERN STREAM ENERGY TRACKING ALONG THE INTERNATIONAL BORDER. THUS
SHOWER CHANCES ON TUESDAY WILL REMAIN ALONG THE INTERNATIONAL BORDER
WHERE THE ENERGY FROM THE UPPER LEVEL TROUGH AND LOW LEVEL
CONVERGENCE ASSOCIATED WITH AN INVERTED SURFACE TROUGH
COINCIDE...WHILE THE SOUTH REMAINS DRY. THE INCREASED CLOUDS AND
SHOWERS NORTH WILL ALSO KEEP TEMPERATURES IN THE 50S...WITH 60S
CENTRAL AND SOUTH.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 325 PM CDT MON OCT 19 2015
TUESDAY EVENING THE UPPER LEVEL TROUGH AND ATTENDANT SURFACE
TROUGH/COLD FRONT MOVES EAST ACROSS WESTERN AND CENTRAL NORTH
DAKOTA. THE MODELS INDICATE THE BEST DYNAMICS OVER NORTHERN NORTH
DAKOTA TUESDAY EVENING...WITH THE UPPER TROUGH MOVING EAST OF OUR
AREA AFTER MIDNIGHT. THUS WILL KEEP CHANCES OF RAIN SHOWERS OVER
NORTHWEST AND NORTH CENTRAL NORTH DAKOTA DURING THE EVENING...THEN
DECREASING CLOUDS FROM WEST TO EAST AFTER MIDNIGHT. LOWS TUESDAY
NIGHT FROM THE MID 30S NORTHWEST TO MID 40S IN THE JAMES VALLEY.
COOLER AIR MOVING INTO THE REGION...WITH DRY HIGH PRESSURE OVER THE
STATE WEDNESDAY. HIGHS WEDNESDAY IN THE 50S...AND LOWS IN THE LOW TO
MID 30S.
WARMER ON THURSDAY AS A FAIRLY STRONG SOUTHERLY FLOW DEVELOPS WITH A
LOW LEVEL JET MOVING NORTHWARD FROM THE SOUTHERN AND CENTRAL PLAINS.
GULF MOISTURE ALSO MOVING NORTH...AND BY THURSDAY AFTERNOON LOOK FOR
HIGHS IN THE 60S AND A CHANCE OF SHOWERS OVER SOUTHERN NORTH DAKOTA.
THURSDAY NIGHT AND FRIDAY ARE THE BEST CHANCES OF RAIN SHOWERS
ACROSS WESTERN AND CENTRAL NORTH DAKOTA AS A GOOD UPPER LEVEL
SHORTWAVE MOVES NORTHEASTWARD FROM THE 4-CORNERS AREA AND PLENTY OF
GULF MOISTURE CONTINUES MOVING NORTH INTO THE NORTHERN PLAINS.
RAIN SHOWERS TAPERING OFF FRIDAY NIGHT AS MORE ZONAL FLOW ALOFT
TAKES HOLD. AS OF NOW THE WEEKEND LOOKS ON THE DRY SIDE WITH
SEASONABLE TEMPERATURES...HIGHS MAINLY IN THE 50S AND LOWS IN THE
30S.
THE MODELS HINT AT THE NEXT CHANCE OF RAIN SHOWERS MOVING IN ON
MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1239 AM CDT TUE OCT 20 2015
A BAND OF LIGHT RAIN SHOWERS OVER THE SOUTHWESTERN PART OF THE
STATE WILL DRIFT NORTH NORTHEAST...EVENTUALLY MOVING OVER
KDIK/KISN/KMOT THROUGH THE OVERNIGHT HOURS. VFR CEILINGS AND
VISIBILITIES ARE EXPECTED THROUGHOUT THE PERIOD UNTIL LATE TUESDAY
AFTERNOON AND INTO THE NIGHT...WHEN SOME MVFR CEILINGS WILL BE
POSSIBLE OVER KISN/KMOT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ZH
SHORT TERM...TWH
LONG TERM...JV
AVIATION...ZH
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
239 AM EDT TUE OCT 20 2015
.SHORT TERM...(TODAY AND TONIGHT)
THERE COULD BE SOME AREAS OF PATCHY FROST THIS MORNING WITH
TEMPERATURES IN THE MID 30 TO MID 40S CURRENTLY AT 2 AM.
CURRENT WATER VAPOR IMAGERY AND RAP UPPER AIR ANALYSIS INDICATES A
DEEPENING TROUGH ACROSS THE WESTERN CONUS WITH UPPER LEVEL HEIGHT
RISES ACROSS THE CENTRAL AND EASTERN CONUS. AT THE SURFACE... THE
HIGH PRESSURE CENTER IS LOCATED JUST TO THE EAST OF THE AREA WITH
SOUTHERLY FLOW EXPECTED TO CONTINUE TODAY. EXPECT ANOTHER SUNNY DAY
WITH PLENTY OF INSOLATION AND UPPER LEVEL HEIGHT
RISES...TEMPERATURES SHOULD CONTINUE TO CLIMB INTO THE MID TO
UPPER 60S ACROSS MOST OF THE AREA. OVERNIGHT LOWS WILL ALSO BE A
BIT WARMER TOMORROW MORNING WITH LOWS IN THE UPPER 30S TO MID 40S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
HIGH PRESSURE WILL REMAIN IN CONTROL THROUGH THE END OF THE WORK
WEEK. RIDGE WILL FLATTEN LATE THIS WEEK...WITH ZONAL FLOW WILL
ALLOW GULF MOISTURE TO SPREAD OVER THE AREA OVER THIS WEEKEND AND
INTO MONDAY...WITH SCATTERED SHOWERS EXPECTED. INCREASE IN
TEMPERATURES AND HUMIDITY WILL RESULT IN SOME WARM TEMPERATURES FOR
LATE-OCTOBER WEATHER ESPECIALLY THURSDAY THROUGH MONDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 69 44 74 47 / 0 0 0 0
KNOXVILLE MCGHEE TYSON AIRPORT, TN 68 42 73 45 / 0 0 0 0
OAK RIDGE, TN 68 41 73 44 / 0 0 0 0
TRI CITIES AIRPORT, TN 67 37 72 40 / 0 0 0 0
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
MA/GC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
327 AM CDT TUE OCT 20 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 216 AM CDT TUE OCT 20 2015
AT 3 AM...A SURFACE LOW WAS LOCATED OVER SOUTHWEST MINNESOTA. A
STATIONARY FRONT EXTENDED EAST FROM THIS LOW FROM FARIBAULT
MINNESOTA TO GREEN BAY WISCONSIN. NORTH OF THIS FRONT TEMPERATURES
WERE IN THE 40S AND 50S. MEANWHILE SOUTH OF THIS FRONT...
TEMPERATURES RANGED FROM THE UPPER 50S TO MID 60S WHICH IS WARMER
THAN OUR NORMAL HIGH TEMPERATURES FOR MID OCTOBER.
FOR THIS AFTERNOON AND EVENING...THE 10.20Z MODELS ARE IN GENERAL
AGREEMENT THAT A SHORT WAVE TROUGH...CURRENTLY LOCATED OVER
EASTERN KANSAS WILL MOVE NORTHEAST INTO EASTERN IOWA THIS
AFTERNOON...AND NORTHERN ILLINOIS AND SOUTHERN WISCONSIN THIS
EVENING. AHEAD OF THIS WAVE...ELEVATED CAPES WILL CLIMB TO AROUND
500 J/KG ACROSS NORTHEAST IOWA AND SOUTHWEST WISCONSIN DURING THE
LATE AFTERNOON AND EVENING. THIS SHOULD BE ENOUGH INSTABILITY FOR
ISOLATED TO SCATTERED SHOWERS TO DEVELOP BETWEEN 20.21Z AND
21.03Z. THE ARW...NMM...AND HRRR COMPOSITE REFLECTIVITY PRODUCT
EVEN HINTS THAT THERE COULD BE SOME ISOLATED THUNDERSTORMS ACROSS
SOUTH CENTRAL AND SOUTHEAST WISCONSIN AND NORTHERN ILLINOIS.
COMPARING THE CURRENT TEMPERATURES TO THE GRIDDED MODEL VALUES...
THE MODELS ARE NOT DOING THAT WELL THIS MORNING ALONG AND SOUTH OF
INTERSTATE 94. THE GRIDDED MINIMUM TEMPERATURES WILL END UP BEING
TOO COLD. PARTLY SUNNY SKIES TODAY WILL ALLOW US TO MIX UP TO
900 MB THIS AFTERNOON. WITH THE GROUND BEING VERY DRY DUE TO THE
LACK OF RAIN DURING THE PAST MONTH...EXPECT THE THERE WILL BE A
SUPER ADIABATIC LAPSE RATE UP TO 900 MB. THIS WILL RESULT IN HIGH
TEMPERATURES IN THESE AREAS CLIMBING INTO THE MID 70S. THIS WILL
BE ABOUT 5 TO 10 DEGREES SHY OF THE RECORDS FOR TODAY. MOST
PLACES HAVE THEIR HIGH TEMPERATURES IN THE LOWER TO MID 80S WHICH
OCCURRED IN 1953...2000...OR 2003.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 216 AM CDT TUE OCT 20 2015
ON WEDNESDAY MORNING...THE 20.00Z MODELS ARE IN GOOD AGREEMENT
THAT A COLD FRONT WILL MOVE THROUGH THE AREA. WITH THE BEST LIFT
AND MOISTURE TRANSPORT BEING TO OUR NORTH AND SOUTHEAST...NOT
SEEING MUCH CHANCE OF PRECIPITATION ALONG IT...SO LOWERED THE RAIN
CHANCES ACROSS WESTERN WISCONSIN TO 20 PERCENT.
FROM FRIDAY INTO SATURDAY...THE MODELS ARE IN GOOD AGREEMENT THAT
THE CLOSED 500 MB LOW...CURRENTLY OVER THE SOUTHWEST UNITED
STATES...WILL LIFT NORTHEAST OUT OF THE CENTRAL AND SOUTHERN
PLAINS ON FRIDAY...MINNESOTA AND WISCONSIN ON FRIDAY NIGHT...AND
THE GREAT LAKES ON SATURDAY. THIS SYSTEM WILL TAP INTO GULF OF
MEXICO AND TROPICAL MOISTURE AS IT MOVES THROUGH THE REGION.
PRECIPITABLE WATER VALUES CLIMB UP TO 1.5 INCHES ON FRIDAY
AFTERNOON /THIS IS 1 TO 2 STANDARD DEVIATIONS ABOVE NORMAL/...AND
THEN QUICKLY DECLINES AS THE COLD FRONT MOVES QUICKLY EAST THROUGH
THE REGION. WITH THE BEST FORCING AND MOISTURE TRANSPORT BEING TO
OUR NORTH AND SOUTHEAST...THE HEAVIEST RAIN MAY MISS OUR AREA.
EVEN IF WE DID SEE SOME HEAVY RAIN...IT SHOULD NOT CREATE ANY
ISSUES BECAUSE IT WILL BE A BRIEF PERIOD AND THAT IT HAS BEEN DRY
SO LONG.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1132 PM CDT MON OCT 19 2015
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD...WITH A
GRADUAL INCREASE IN THICKER HIGH CLOUDS THROUGH THE MORNING HOURS.
WILL ALSO LIKELY SEE A BAND OF THICKER MID LEVEL CLOUDS IN THE
11-13KFT RANGE FOR A TIME AT BOTH SITES THROUGH SUNRISE...WITH
SOUTHERLY WINDS IN THE 8 TO 12 KNOT RANGE SHIFTING SOUTHEAST
THROUGH THE LATE AFTERNOON AND EVENING WITH A FRONTAL BOUNDARY
NEARBY. SCATTERED SHOWERS THIS AFTERNOON AND EVENING LOOK TO HOLD
JUST SOUTH OF THE TERMINAL SITES...THOUGH WILL HAVE TO WATCH
NORTHWARD EXTENT AS THERE IS SOME CHANCE FOR THOSE SHOWERS TO
WORK A BIT FARTHER NORTH.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...LAWRENCE
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1046 AM CDT TUE OCT 20 2015
.UPDATE...
ISSUED AT 1046 AM CDT TUE OCT 20 2015
Another breezy and unseasonably warm day is unfolding across
central Illinois...courtesy of high pressure anchored over the
southeast CONUS. The only potential fly-in-the-ointment is a small
cluster of convection that has developed ahead of a cold front
over northwest Missouri. These storms have been tracking to the E/NE
this morning and will continue to do so over the next few hours.
Most model guidance suggests the convection will remain W/NW of the
KILX CWA: however, the HRRR shows it potentially tracking across
locations northwest of the Illinois River by mid to late afternoon.
Based on current radar/satellite loops...will trend toward the HRRR
solution. As a result...will be maintaining slight chance PoPs for
showers across the NW CWA this afternoon. Elsewhere around the
area...am expecting partly to mostly sunny skies with high
temperatures climbing well into the 70s.
&&
.SHORT TERM...(Today)
ISSUED AT 329 AM CDT TUE OCT 20 2015
Gusty southwest winds will highlight the weather today. The winds
will be driven by a relatively tight pressure gradient across IL
from NW to SE, as our area remains wedged between high pressure in
the southeast states and a cold front extending from Lake Superior
to western Kansas. The cold front will sag closer to IL this
afternoon, with spotty showers or sprinkles possible after 21z/4 pm
for areas NW of the Illinois river. Moisture content of the
approaching airmass will be limited, so any rainfall amounts will be
very light. Despite increasing cloud cover this afternoon, high
temps will climb above yesterday, with readings in the mid 70s
toward Indiana and upper 70s in west of I-55.
.LONG TERM...(Tonight through Monday)
ISSUED AT 329 AM CDT TUE OCT 20 2015
High pressure has settled over the southern Atlantic Coast this
morning as south/southwesterly flow continues into the Midwest. The
warmer temperatures will continue through tomorrow. The overnight
forecast is mainly dry with the exception of areas along and NW of
the Illinois River Valley. A weak boundary to the NW will settle
into the Midwest providing a focus for some sct precip. The airmass
that the boundary is running into is fairly dry and precip will be
difficult to come by, but the models are persistent in developing a
few showers. Warm temps through Wednesday and dry...but a weak
boundary settling/developing in the region will allow for a more
northeasterly flow to winds through the end of Thursday and limit
the afternoon warming. Models previously kept the sct showers to the
north, however, recent runs are dropping the sfc wind convergence a
little further south. As of yet, leaving Thursday dry. The 00z GFS
came in with a thin line of showers associated with this front and
cannot rule out the possible addition of some low pops for Thursday,
but will hinge greatly on how much moisture can actually return to
the atmosphere over the next few days with the continued southerly
flow off of the Gulf Coast, and more southwesterly aloft from the
deeper moisture to the SW. Previously drier forecast is starting to
erode well before the weekend system, but a lot hinges on the
moisture advection from the SW, so the pops will remain low.
The upper low over the SW finally kicks out and through the Midwest
bringing the best precip chances in the forecast for this
weekend...Friday night and Saturday. Have kept the mention of
thunder in the southern half of the CWA for Saturday as the front
settles into the area with the max heat of the afternoon. Temps a
little more seasonal going into the work week with highs in the
lower 60s and lows in the low to mid 40s.
&&
.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
ISSUED AT 700 AM CDT TUE OCT 20 2015
VFR conditions are expected through this forecast period. The main
aviation concern continues to be with the threat for LLWS early
this morning, especially from KSPI-KBMI. There will be about
30-35 knots of speed difference over a short distance aloft, with
winds at 1200-1800 feet from around 230 deg at 45 kts, and surface
winds at 180-210 direction at 10 to 15 kts. Further east at KDEC
and KCMI, it appears the winds will remain just below criteria
early this morning, so will leave the threat out at those two
sites. Winds will increase quickly this morning, with sustained
13-17kt and gusts to 25kt. Wind gusts will diminish with sunset,
but sustained speeds could remain 10-12kt overnight from the
south.
Clouds will begin to increase across northwest Illinois later
this afternoon as the cold front approaches. Cirrus and alto-cu
will be the primary cloud types late today and tonight as spotty
showers develop near PIA and BMI. No mention of VCSH was included
with this TAF issuance, due to the low chances.
&&
.FIRE WEATHER...
ISSUED AT 329 AM CDT TUE OCT 20 2015
Fire weather risk will remain a concern today, due to SW winds
gusting up to 20-25 mph, low relative humidity of 25-30% and dry
fuel moisture. Increasing cloud cover ahead of the approaching cold
front will reduce mixing heights this afternoon, keeping winds lower
than yesterday. Increasing dewpoints will keep relative humidity
slightly higher as well, which prevent us from reaching Red Flag
Warning criteria today. However, burning will still be discouraged
due to the borderline conditions.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Barnes
SHORT TERM...Shimon
LONG TERM...HJS
AVIATION...Shimon
FIRE WEATHER...Shimon
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
610 AM CDT TUE OCT 20 2015
...UPDATED AVIATION SECTION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 245 AM CDT TUE OCT 20 2015
NAM, GFS, and RAP were all in good agreement with another upper
level disturbance, located just west of Baja California at 00z
Tuesday, approaching southwest Kansas early tonight. A surface
trough of low pressure will be located from southeast Colorado
into south central Nebraska by late day. Latest NAM indicating
limited low level forcing along this front and 0-6km shear will be
20 knots or less. CAPE values near the surface trough is forecast
to be less than 600 J/Kg so at this time not overly excited about
late day convection, however unable to rule out a few isolated
storms in far western Kansas early this evening. The chance for
will improve during the overnight hours as moisture and improving
upper level lift develops ahead of an upper level trough that is
forecast to cross western Kansas tonight. At this time the better
forcing will be across far western Kansas early tonight and then
shift north after midnight.
The potential for afternoon cloud cover will make temperatures a
little tricky today, however am expecting a fair amount of sun so
will based highs on 00z Wednesday 850mb temperatures. This is
close to the latest guidance of highs mainly in mid 80s.
.LONG TERM...(Wednesday THROUGH Monday)
ISSUED AT 245 AM CDT TUE OCT 20 2015
On Wednesday moisture will continue to improve in the 850mb to
700mb level as another upper level disturbance approaches from the
southwest. Better difluent flow will be present aloft, especially
late day as a surface boundary drops south into southwest Kansas.
Given this will stay close to the previous forecast with
precipitation chances increasing late day and early Wednesday
night.
The best chance for widespread precipitation still appears to
occur across western and central Kansas late Wednesday night and
Thursday given the moisture forecast across western Kansas and the
location of the upper level jet streak east of the upper low that
will be crossing the four corners region on Thursday. Also given
the expected precipitation and cloud cover will continue to favor
lows near or above guidance while undercutting highs on Thursday.
Thursday night into Friday the upper low opens up as it lifts
northeast into the northern Plains. As this upper level trough
crosses western Kansas Thursday night the precipitation chances is
expected to taper off from west to east. There will then be a
slight chance for some showers or even an isolated thunderstorm
late Friday night as a weak upper level trough crosses the central
high plains.
The weekend will be mainly dry and cool with highs mainly in the
60s Both Saturday and Sunday.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z Wednesday MORNING)
ISSUED AT 608 AM CDT TUE OCT 20 2015
A surface trough over extreme western KS will contribute to
different gradient wind speeds across the area. The more breezy
site with higher gusts to around 25 knots will likely be at DDC
this afternoon. If any showers or storms follow the weak shortwave
models in the NAM later this evening or tonight, conditions will
still be VFR and short lived; too low confidence for mention in
the terminals.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 84 56 73 56 / 0 20 40 80
GCK 85 55 67 53 / 0 30 60 80
EHA 82 55 66 53 / 20 30 70 80
LBL 84 57 73 56 / 20 20 50 80
HYS 85 56 70 54 / 0 30 40 60
P28 83 60 77 59 / 20 10 30 70
&&
.DDC Watches/Warnings/Advisories...NONE.
&&
$$
SHORT TERM...Burgert
LONG TERM...Burgert
AVIATION...Russell
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
734 AM EDT TUE OCT 20 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 541 AM EDT TUE OCT 20 2015
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A DEEP MID LEVEL LOW
MOVING FROM HUDSON BAY INTO NRN QUEBEC. TO THE W...A TROF IS OVER
THE ROCKIES IN BOTH THE NRN AND SRN STREAMS. THE NRN STREAM
SHORTWAVE WILL BECOME RATHER VIGOROUS AS IT MOVES INTO THE UPPER
GREAT LAKES AND NRN ONTARIO WED NIGHT. AT THE SFC...COLD FRONT
ASSOCIATED WITH THE DEEP HUDSON BAY MID LEVEL LOW IS MOVING S ACROSS
UPPER MI ATTM. BRISK N TO NE WINDS HAVE DEVELOPED ACROSS LAKE
SUPERIOR BEHIND THE FRONT AND AHEAD OF SFC HIGH PRES BUILDING FROM
NRN MANITOBA INTO NRN ONTARIO. SKIES ARE MOSTLY CLEAR ACROSS THE
FCST AREA EARLY THIS MORNING. A BAND OF STRATOCU BEHIND FRONT IS
CONFINED TO THE E OF LAKE SUPERIOR SO FAR...AND A BKN NARROW BAND OF
MID LEVEL CLOUDS PRODUCING SOME RADAR RETURNS IS LURKING JUST S AND
SW OF MENOMINEE.
INITIALLY TODAY...THERE IS SOME CONCERN THAT A FEW -SHRA COULD BRUSH
THE FAR SCNTRL FCST AREA. PER LATEST RAP...LINGERING STEEP MID LEVEL
LAPSE RATES AND CONVERGENCE OF 850MB FLOW APPEAR TO BE AIDING THE
MID CLOUD/RADAR RETURNS CURRENTLY S AND SW OF MENOMINEE. HRRR RUNS
OVERNIGHT HAVE CONSITENTLY INDICATED THAT THERE WILL BE SOME
NORTHWARD DEVELOPMENT OF -SHRA/SPRINKLES INTO MENOMINEE COUNTY THIS
MORNING/EARLY AFTN. WHILE THERE IS STILL DRY AIR TO OVERCOME IN THE
LOWER LEVELS PER 00Z KGRB SOUNDING...HAVE INTRODUCED ISOLD -SHRA FOR
MENOMINEE COUNTY THIS MORNING BASED ON INCREASING RADAR
REFLECTIVITIES. OTHERWISE...A COOL NE FLOW LOCKS IN TODAY AS HIGH
PRES BUILDS SE ACROSS NRN ONTARIO. AT THIS POINT...WITH POST FRONTAL
STRATOCU REMAINING E OF LAKE SUPERIOR SO FAR AND MOVING SSE...IT
DOES NOT APPEAR THAT A BKN-OVC LOWER CLOUD DECK WILL DEVELOP IN THE
UPSLOPE AREAS TODAY. MAY SEE SOME SCT STRATOCU. OTHERWISE...AFTER A
GENERALLY MOSTLY SUNNY START...HIGH CLOUDS WILL BE ON THE INCREASE
FROM THE W AND SW. OBVIOUSLY WITH THE PASSAGE OF COLD FRONT AND NE
WINDS TODAY...IT WILL BE COOLER TODAY THAN YESTERDAY. EXPECT HIGHS
GENERALLY FROM THE UPPER 40S OVER THE HIGHER TERRAIN OF THE KEWEENAW
AND NCNTRL TO THE LOW/MID 50S ELSEWHERE.
AS SHORTWAVE ENERGY MOVES ACROSS THE NRN PLAINS/SCNTRL CANADA
TONIGHT...850MB WAA DEVELOPS ACROSS THE AREA. HOWEVER...
ISENTROPICALLY...MODELS GENERALLY SUGGEST BETTER MOIST ASCENT TO THE
SE OF THE FCST AREA. MEANWHILE...BEST DEEP LAYER FORCING ASSOCIATED
WITH APPROACHING SHORTWAVE ENERGY IS TO THE NW OF THE FCST AREA. AS
A RESULT...IT APPEARS THE 2 MAIN AREAS OF DEVELOPING PCPN WILL SPLIT
THE FCST AREA TONIGHT...AND THAT IS EXACTLY WHAT THE PCPN FIELDS
FROM THE ALL THE AVBL OPERATIONAL MODELS SHOW. HAVE THUS CUT BACK ON
POPS TONIGHT TO SCHC WITH THE LOWEST POPS ACROSS THE CNTRL FCST
AREA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 445 AM EDT TUE OCT 20 2015
NEAR TO SLIGHTLY ABOVE NORMAL TEMPERATURES THROUGH SATURDAY...THEN
COOLER AIR RETURNS. A PERIOD OF GUSTY WINDS CAN BE EXPECTED
WEDNESDAY AFTERNOON AND EVENING OVER THE KEWEENAW PENINSULA AND
ALONG LAKE SUPERIOR.
WEDNESDAY AND WEDNESDAY NIGHT...A SURFACE LOW AND UPPER LEVEL 500MB
SHORTWAVE STRETCHING FROM MANITOBA...SOUTHWARD INTO MN WILL BEGIN TO
SHIFT EASTWARD TOWARD UPPER PENINSULA. AS THE LOW CENTER SLIDES
ACROSS LAKE SUPERIOR THROUGH THE DAY AND THE ASSOCIATED COLD FRONT
SLIDES THROUGH THE AREA...EXPECT WIDESPREAD RAIN SHOWERS TO DEVELOP.
THE BEST FORCING WILL REMAIN CLOSER TO THE LOW
CENTER...HOWEVER...THERE WILL BE ENOUGH FORCING ACROSS THE REST OF
THE AREA...AS SHOWN BY ANALYZING 1000-500MB RH ALONG WITH DEEP LAYER
QCONV...TO CREATE WIDESPREAD RAIN SHOWERS. THIS LOW WILL QUICKLY
DEPART TO THE EAST OF THE AREA WEDNESDAY EVENING AS IT RAPIDLY
INTENSIFIES AND MUCH DRIER DEEP LAYER AIR SURGES IN BEHIND IT ON
WESTERLY TO NORTHWESTERLY WINDS. THIS WILL ALLOW FOR A VERY QUICK
END TO THE RAIN SHOWERS FROM WEST TO EAST THROUGH THE EVENING HOURS.
ADDITIONALLY...BEHIND THE COLD FRONT...THE PRESSURE GRADIENT WILL
INCREASE BETWEEN THE DEPARTING LOW AND THE HIGH PRESSURE QUICKLY
BUILDING IN BEHIND IT WEDNESDAY NIGHT. THIS WILL ALLOW FOR GUSTY
WEST TO NORTHWESTERLY WINDS. COULD SEE GUSTS UP TO 30 TO 40 MPH OVER
THE KEWEENAW PENINSULA AND NEAR LAKE SUPERIOR IN THE LATE AFTERNOON
AND EVENING HOURS...WITH A BRIEF PERIOD OF GALES POSSIBLE OVER LAKE
SUPERIOR. THIS WILL BE ESPECIALLY TRUE IF STRONGER WINDS MIX DOWN TO
THE SURFACE. WINDS AT 925MB TO 900MB ARE RIGHT AROUND 35 TO 40
KNOTS...AGAIN WITH CAA...IT WILL BE VERY POSSIBLE FOR THESE STRONGER
WINDS TO MIX DOWN...ESPECIALLY OVER THE KEWEENAW PENINSULA AND LAKE
SUPERIOR. THE SHOWERS COULD LINGER A BIT LONGER OVER THE EASTERN
U.P. DUE TO THE PROXIMITY TO THE DEPARTING LOW ALONG WITH CAA INTO
THE AREA. 850MB TEMPERATURES ARE PROGGED TO DROP TO NEAR
-2C LATE WEDNESDAY NIGHT...WITH THE WEST TO NORTHWEST FLOW...WHICH
WILL AT A MINIMUM KEEP THE POTENTIAL FOR LAKE EFFECT CLOUD COVER
OVER THE EAST HALF NEAR LAKE SUPERIOR.
THURSDAY THROUGH FRIDAY...THE GENERAL TREND IS FOR A SURFACE RIDGE
AND ASSOCIATED UPPER LEVEL RIDGE TO QUICKLY BUILD FROM THE NORTHERN
PLAINS AND CANADA INTO THE UPPER GREAT LAKES THURSDAY AND LINGER
THROUGH MOST OF THE DAY FRIDAY. THIS WILL KEEP MAINLY DRY CONDITIONS
IN THE FORECAST. THERE MAY BE SOME LINGERING LOW CLOUDS AS 850MB
TEMPS SLOWLY START TO REBOUND OVER THE EAST AND THE LOW CONTINUES TO
DEPART THROUGH QUEBEC THROUGH THURSDAY AFTERNOON. OTHERWISE...FOR
THE REST OF THE AREA SKIES WILL BE PARTLY CLOUDY THROUGH FRIDAY
MORNING. FRIDAY AFTERNOON...THE NEXT UPPER LEVEL TROUGH AND SURFACE
LOW SLIDING ACROSS SOUTHERN CANADA...ALONG WITH ASSOCIATED COLD
FRONT...WILL APPROACH THE REGION FROM THE WEST. THIS WILL ALLOW FOR
INCREASING CLOUDS FROM THE WEST...HOWEVER...MOST OF THE AREA SHOULD
REMAIN DRY FOR DURING THE DAY FRIDAY.
FRIDAY NIGHT SATURDAY...THE AFOREMENTIONED LOW PRESSURE SYSTEM AND
ASSOCIATED COLD FRONT WILL CONTINUE TO SLIDE EAST ACROSS THE AREA.
MODELS ARE BECOMING MORE SETTLED ON A SOLUTION WITH THE SURFACE LOW
SLIDING FROM NORTHERN MN FRIDAY NIGHT TO NEAR JAMES BAY BY SATURDAY
EVENING. THIS WILL DRAG A COLD FRONT THROUGH THE AREA THROUGH THE
DAY SATURDAY. THERE WILL BE PLENTY OF MOISTURE AND FORCING ALONG THE
FRONT TO ALLOW FOR A RAINY SATURDAY ACROSS MUCH OF THE U.P. ANOTHER
THING TO NOTE...EVEN THOUGH THIS IS STILL SEVERAL DAYS OUT...IS THAT
BOTH THE GFS/EC SHOW THE UPPER LEVEL SHORTWAVE ASSOCIATED WITH THE
TROUGH DIGGING MUCH FARTHER SOUTH THAN THE EARLIER MODEL RUNS. THIS
ACTS TO INTENSIFY THE SURFACE LOW AS THE 500MB SHORTWAVE IS
STAGGERED BACK TO THE WEST OF THE SURFACE LOW. IF THE LOW DOES
INTENSIFY AS PROGGED...WE COULD BE LOOKING AT ANOTHER PERIOD OF
GUSTY WINDS ACROSS THE AREA ON CAA...DUE TO FAIRLY STRONG PRESSURE
GRADIENT ALONG WITH MIXING OF FAIRLY STRONG WINDS DOWN FROM 850MB.
AGAIN THIS IS A WAYS OUT...BUT DEFINITELY SOMETHING TO KEEP IN MIND.
SATURDAY NIGHT THROUGH THE EXTENDED...THE GFS/EC BOTH AGREE ON A
DECENT RIDGE BUILDING OVER THE WESTERN CONUS WITH BROAD TROUGHING
SETTLING IN OVER THE EASTERN U.S. THROUGH THIS TIME PERIOD...850MB
TEMPS ARE PROGGED TO DROP INTO THE -4C TO -8C RANGE WHICH WILL
SUPPORT LAKE EFFECT CLOUD COVER AND LAKE EFFECT RAIN DURING THE DAY
AND POSSIBLY LAKE EFFECT SNOW SUNDAY NIGHT AS THE COLDER AIR SLIDES
INTO THE AREA. AT THE TIME BEING THE BEST CHANCE FOR LAKE EFFECT
PRECIPITATION WOULD BE FOR WEST TO WEST NORTHWEST FAVORED AREAS.
AGAIN THIS IS ABOUT A WEEK OUT SO THINGS CAN DEFINITELY CHANGE AND
THE EXACT DETAILS WILL STILL NEED TO BE IRONED OUT AS CONFIDENCE IN
THE MODELS INCREASES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 734 AM EDT TUE OCT 20 2015
VFR CONDITIONS WILL CONTINUE AT KIWD/KCMX/KSAW THRU AT LEAST THE
EVENING HOURS AS LOW LEVELS REMAIN DRY. MOISTURE WILL BEGIN TO
INCREASE LATE TONIGHT AS A LOW PRES TROF APPROACHES. WITH AN UPSLOPE
WIND COMPONENT...KCMX/KSAW WILL LIKELY SEE CIGS FALL TO MVFR VERY
NEAR THE END OF THE FCST PERIOD WITH THE LOWER CIGS AT KSAW DUE TO
UPSLOPE FLOW ORIGINATING OFF THE WARMER WATERS OF LAKE MICHIGAN.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 541 AM EDT TUE OCT 20 2015
HIGH PRES BUILDING SE ACROSS NRN ONTARIO WILL LEAD TO BRISK NE WINDS
IN THE 15-30KT RANGE ACROSS LAKE SUPERIOR TODAY. WINDS WILL BE
STRONGEST OVER WESTERN LAKE SUPERIOR WHERE THE TERRAIN WILL FUNNEL
AND ENHANCE THE FLOW. WINDS WILL THEN VEER TO THE E-SE TONIGHT/WED
MORNING AS HIGH PRES MOVES TO QUEBEC AND A LOW PRES TROF APPROACHES.
THE STRONGER SE WINDS UP TO 30KT ARE MOST LIKELY OVER THE E HALF OF
THE LAKE ON WED. A LOW PRES CENTER WILL DEVELOP ALONG THE TROF AND
PASS JUST N OF LAKE SUPERIOR WED AFTN. AS THIS OCCURS...A FAVORABLY
ALIGNED PRES RISE/FALL COUPLET WILL GIVE AN ISALLOBARIC BOOST TO THE
WESTERLY WINDS IN THE WAKE OF COLD FROPA. RESULT SHOULD BE A FEW HRS
OF SOME GALE FORCE GUSTS AROUND THE W SIDE OF THE KEWEENAW LATE WED
AFTN/EVENING AND THEN OVER THE ERN PART OF THE LAKE WED EVENING. FOR
NOW...HELD OFF ON A GALE WATCH GIVEN THIS NEW MODEL TREND FOR
STRONGER WINDS. WINDS WILL SHIFT NW WED NIGHT THEN DIMINISH THU AS
HIGH PRES BUILDS INTO THE UPPER GREAT LAKES. WINDS WILL THEN BE ON
THE INCREASE FRI/SAT AS ANOTHER LOW PRES TROF SWEEPS THRU THE UPPER
GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KEC
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
903 AM MDT TUE OCT 20 2015
.UPDATE...
BAND OF PRECIPITATION STRETCHING FROM NORTHERN ROSEBUD COUNTY
SOUTHWESTWARD INTO RED LODGE THIS MORNING. THIS AREA OF RAIN HAS
BEEN SLOWLY SHIFTING EAST AND DECREASING. HRRR TREND ADVERTISING A
CONTINUING OF THE DISSIPATION TREND...BUT AT A MUCH MORE
ACCELERATED PACE THAN WHAT IS ACTUALLY HAPPENING. HAVE RAISED POPS
A LITTLE MORE FOR PARTS OF CENTRAL AND EASTERN ZONES THIS MORNING
AND PUSHED POPS FARTHER EAST INTO THE AFTERNOON. BELIEVE THERE
WILL BE MORE REDEVELOPMENT THIS AFTERNOON AS A SECONDARY WAVE OF
ENERGY SWINGS ACROSS THE FORECAST AREA...BUT COVERAGE WILL BE MORE
SCATTERED. DRYING TREND FOR TONIGHT LOOKS ON TRACK WITH THE
POSSIBILITY OF FOG FORMATION. TWH
&&
.SHORT TERM...VALID FOR TDY AND WED...
THE UPPER LOW THAT WAS OVER THE GREAT BASIN AREA ON MONDAY HAS
BECOME LESS ORGANIZED LEAVING GENERALLY A LARGE AREA OF
TROUGHINESS ACROSS THE NORTHERN AND CENTRAL ROCKIES. A PORTION OF
THE LOW DID MOVE NORTH INTO WYOMING AND SOUTH CENTRAL MONTANA LAST
EVENING PROVIDING SOME UPPER LEVEL DIVERGENCE AND LIFT ACROSS
PORTIONS OF SOUTHERN MONTANA. AREAS OF PRECIPITATION ROTATED NORTH
AND WEST AROUND THIS LOW BRINGING LIGHT TO MODERATE RAIN ACROSS
OUR CENTRAL AND WESTERN LOCATIONS LAST EVENING THROUGH THE EARLY
MORNING HOURS TODAY. RADAR IS CURRENTLY SHOWING AN AREA OF LIGHT
TO MODERATE RAIN ALONG AND NORTH OF A LIVINGSTON-HARDIN- FORSYTH
LINE.
WATER VAPOR IMAGERY SHOWING A PORTION OF THE UPPER LOW ACROSS
SOUTHEAST MONTANA. AS THIS LOW MOVES NORTHEAST...THE AREA OF RAIN
WILL SHIFT SOUTHEAST THIS MORNING INTO EARLY THIS AFTERNOON. THE
HRRR MODEL HAS BEEN HANDLING THIS PRECIP FAIRLY GOOD SINCE LAST
EVENING AND DOES PROG THE AREA OF RAIN TO SHIFT SOUTHEAST LATER
THIS MORNING. AS A RESULT...WE CONTINUE LIKELY POPS ALONG AND
NORTH OF A LIVINGSTON-BILLINGS-HARDIN LINE FOR THIS MORNING. THE
HRRR HAS BEEN DOING PRETTY GOOD WITH THE PRECIP AND HAS IT
SHIFTING SOUTHEAST AND BECOMMING MORE SCATTERED IN NATURE THIS
AFTERNOON. WILL CONTINUE THE TREND OF SHIFTING THE POPS SOUTH AND
EAST AND LOWERING THEM TO MORE OF A HIGH CHANCE.
THE PRECIPITATION WILL QUICKLY END FROM WEST TO EAST THIS EVENING
AND IS EXPECTED TO BE COMPLETELY OUT OF THE FORECAST AREA BY
MIDNIGHT. MODELS ARE SHOWING AREAS OF CLEARING AFTER MIDNIGHT
TONIGHT. THIS COMBINED WITH THE LOW LEVEL MOISTURE FROM RAIN
DUIRNG THE PAST 24 HOURS WILL ALLOW FOR THE POSSIBILITY OF PATCHY
FOG ACROSS ALL BUT THE EASTERN AREAS. TEMPERATURES TODAY WILL BE
COOLER WITH READINGS IN THE UPPER 50S TO LOWER 60S. MOSTLY SUNNY
SKIES...DRY CONDITIONS AND SLIGHTLY WARMER TEMPERATURES WILL
RETURN ON WEDNESDAY. HOOLEY
.LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON...
LOW OVER THE SOUTHWESTERN CONUS WILL OPEN AND LIFT UP THE HIGH
PLAINS THURSDAY...AND SHOULD BRING A PERIOD OF RAIN TO OUR FAR
EAST THURSDAY NIGHT INTO FRIDAY. ALL MODELS SUGGEST A SIMILAR
TRACK SO WITH IMPROVED CONFIDENCE HAVE RAISED POPS TO LIKELY FOR
FALLON AND CARTER COUNTIES. PWAT PLUME ASSOCIATED WITH THIS
ENERGY WILL BE ANOMALOUSLY HIGH PER TAP OF TROPICAL MOISTURE.
EXPECTING PCPN AMOUNTS ON THE ORDER OF A HALF INCH BUT WE COULD
SEE CLOSE TO AN INCH ALONG THE DAKOTAS BORDER IF ASCENT LASTS LONG
ENOUGH...BUT THIS WAVE WILL BE COMPETING WITH DRIER WEST FLOW
OVER THE NORTHERN ROCKIES. SPEAKING OF WHICH...A PACIFIC SHORTWAVE
WILL MOVE ACROSS THE ROCKIES AND BRING A CHANCE OF SHOWERS FOR OUR
WEST AND CENTRAL PARTS THURSDAY NIGHT AND FRIDAY. MODELS STILL
TRYING TO RESOLVE HOW MUCH PHASING WILL OCCUR BETWEEN THE PACIFIC
WAVE AND SOUTHWESTERN TROF...SO STRESS UNCERTAINTY WITH REGARD TO
PCPN CHANCES ON FRIDAY. AFTER A MILD DAY WITH TEMPS IN THE 60S ON
THURSDAY WE SHOULD SEE HIGHS CLOSER TO NORMAL AND IN THE 50S
FRIDAY.
MODELS SEEM TO BE CONVERGING ON A SCENARIO WHICH WOULD KEEP NW
FLOW OVER THE AREA THROUGH THE WEEKEND AS A RIDGE BUILDS ALONG THE
WEST COAST OF CANADA. THOUGH THEY ARE SIMILAR IN A GENERAL SENSE
THE MODELS ARE IN COMPLETE DISAGREEMENT WITH REGARD TO A CANADIAN
CLIPPER AND/OR OVERRUNNING PACIFIC MOISTURE. AFTER WHAT CURRENTLY
LOOKS TO BE A DRY SATURDAY...THERE IS POTENTIAL FOR A CLIPPER
SYSTEM AND SOME LIGHT PCPN SUNDAY TO SUNDAY NIGHT. HAVE EXPANDED
SLIGHT POPS FOR THESE PERIODS. CONSENSUS IS FOR BUILDING HEIGHTS
AND A DRY MONDAY. AS FOR TEMPERATURES...GIVEN THE NW FLOW IS
CONFLUENT AND SUPPORTS SFC RIDGING OVER THE PLAINS...AM EXPECTING
COOLER NORTH TO EAST WINDS TO PREVAIL OVER THE WEEKEND WITH SUNDAY
BEING THE COOLER OF THE TWO DAYS. EXPECT HIGHS BY SUNDAY ONLY IN
THE UPPER 40S OR LOWER 50S...BUT WITH ENOUGH PUSH OF COOLER
CANADIAN AIR WE MIGHT BE COOLER THAN THAT. IT IS LATE OCTOBER
AFTER ALL.
STILL LOOKING FOR THE FIRST FREEZE AT THE BILLINGS AIRPORT AND IT
COULD HAPPEN NEXT WEEKEND. LATEST FIRST FREEZE ON RECORD OCCURRED
ON OCTOBER 27TH. JKL
&&
.AVIATION...
A SLOW MOVING WEATHER SYSTEM WILL CONTINUE TO BRING RAIN
ESPECIALLY WEST OF KMLS-K4BQ THIS MORNING. EXPECT LOCAL MVFR AT
LOWER ELEVATIONS...AND MOUNTAINS WILL BE MOSTLY OBSCURED IN
RAIN/SNOW. PRECIPITATION WILL SHIFT TO THE SOUTHEAST AND BECOME
SCATTERED THIS AFTERNOON...AND DISSIPATE THIS EVENING. EXPECT VFR
FLIGHT CONDITIONS TO PREVAIL TONIGHT...WITH FOG POSSIBLY FORMING
OVERNIGHT PRODUCING LOCAL IFR CONDITIONS. NW WIND GUSTS TO 25 KTS
WILL BE COMMON TODAY...ESPECIALLY EAST OF KBIL. JKL/TWH
&&
.PRELIMINARY POINT TEMP/POPS...
TDY WED THU FRI SAT SUN MON
-------------------------------------------------------
BIL 060 039/062 042/066 041/058 035/057 033/052 033/058
6/W 10/U 00/B 12/W 21/B 12/W 21/B
LVM 054 034/065 038/065 033/056 030/057 030/054 030/061
4/W 10/U 01/U 22/W 21/B 12/W 21/B
HDN 064 035/065 037/068 038/060 032/060 031/055 030/061
8/W 10/U 01/B 12/W 21/B 12/W 21/B
MLS 063 036/063 037/068 041/058 036/058 033/054 032/059
5/W 10/U 01/U 51/B 11/B 11/B 11/B
4BQ 063 034/062 040/067 040/058 034/058 031/053 031/059
4/W 10/U 02/W 51/N 11/B 11/B 21/B
BHK 061 033/061 035/065 041/056 033/056 030/052 029/055
3/W 10/U 01/B 64/W 11/B 11/B 11/B
SHR 060 037/063 039/066 039/057 033/057 030/054 030/059
4/W 20/U 01/B 32/W 21/B 12/W 21/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
800 AM PDT TUE OCT 20 2015
.SYNOPSIS...A LOW PRESSURE SYSTEM WILL BECOME CENTERED NEAR YUMA
ARIZONA TODAY AND BRING SHOWERS AND ISOLATED THUNDERSTORMS THROUGH
THE MIDDLE OF THE WEEK...MAINLY TO NORTHWEST ARIZONA AND NEARBY
AREAS OF SOUTHEAST NEVADA AND CALIFORNIA. SLIGHTLY BELOW NORMAL
TEMPERATURES CAN BE EXPECTED THIS WEEK ALONG WITH NORTH BREEZES
TUESDAY AND WEDNESDAY.
&&
.UPDATE...QUICK UPDATE TO ADJUST POPS, WEATHER, SKY COVER, AND QPF,
MAINLY TO ACCOUNT FOR THE ONGOING LINE OF THUNDERSTORMS ACROSS
SOUTHEAST MOHAVE COUNTY, NEAR WIKIEUP. THE REST OF THE FORECAST FOR
TODAY LOOKS GOOD, ACCORDING TO THE LATEST GUIDANCE.
&&
.PREVIOUS DISCUSSION...
232 AM PDT TUE OCT 20 2015
.SHORT TERM...TODAY THROUGH THURSDAY NIGHT.
NOW...A VIGOROUS SHORTWAVE HAS ROUNDED THE BASE OF THE LONGWAVE
TROUGH DRAPED ACROSS THE WESTERN CONUS. THIS HAS RESULTED IN AN AREA
OF UPWARD FORCING AND CONVECTION ACROSS WESTERN ARIZONA. DISCRETE
SUPERCELLS WERE NOTED OVER YAVAPAI COUNTY BETWEEN 06Z-07Z WHICH THEN
MOVED INTO SOUTHEASTERN MOHAVE COUNTY WHERE THEY WEAKENED DUE TO
LIMITED INSTABILITY. STILL...MODERATE CONVECTION CONTINUE ACROSS THE
EASTERN HALF OF THE COUNTY.
TODAY...LAST SEVERAL RUNS OF THE HRRR HAVE INDICATED THE
DEVELOPMENT OF AN AREA OF SHOWERS WITH EMBEDDED STORMS OR EVEN A
MESOSCALE CONVECTIVE VORTEX (MCV) OVER SOUTHERN MOHAVE COUNTY
BETWEEN 12Z-15Z THIS MORNING. THIS ACTIVITY IS THEN FORECAST TO MOVE
NORTH-NORTHWEST THROUGH MID-DAY BEFORE WEAKENING. THIS WOULD THEN BE
FOLLOWED BY THE DEVELOPMENT OF DIURNALLY DRIVEN STORMS ALONG AND
SOUTH OF THE I-15 CORRIDOR. YESTERDAY`S GUIDANCE INDICATED THE
POTENTIAL FOR A PUSH OF COLD POOL DRIVEN CONVECTION WESTWARD OUT OF
MOHAVE COUNTY THIS EVENING...HOWEVER THE MOST RECENT GUIDANCE HAS
BACKED OFF ON THAT IDEA...DISSIPATING CONVECTION AFTER SUNSET. HAVE
HELD ON TO A SLIGHT CHANCE OF CONVECTION OVERNIGHT FROM LAS VEGAS
EAST...BUT COVERAGE IS EXPECTED TO BE VERY ISOLATED. OUTSIDE OF
CONVECTION...GUSTY NORTH WINDS ARE EXPECTED FROM THE COLORADO RIVER
VALLEY WEST IN THE AS ANOTHER AS SHORTWAVES REINFORCE THE GRADIENT
ACROSS THE REGION.
WEDNESDAY...CONVECTION IS EXPECTED TO BECOME CONFINED TO MOHAVE
COUNTY...AND WILL LARGELY BE DIURNALLY DRIVEN DURING THE AFTERNOON.
GUSTY NORTH WINDS WILL CONTINUE FOR MOST AREAS IN THE FORECAST AREA.
THURSDAY...CONVECTION CHANCES CONTINUE TO DECREASE...AND WILL BE
LIMITED TO NORTHERN MOHAVE AND EASTERN LINCOLN COUNTIES. WINDS
EXPECTED TO DIMINISH BY THURSDAY.
TEMPERATURES WILL REMAIN SLIGHTLY BELOW NORMAL...BUT WITH A SLOW
WARMING TREND THROUGH THE SHORT TERM PERIOD.
.LONG TERM...FRIDAY THROUGH MONDAY.
DRY CONDITIONS WITH NORTHWEST TO QUASI-ZONAL FLOW ARE EXPECTED
ACROSS THE AREA THROUGH THE MAJORITY OF THE LONG TERM PERIOD.
EMBEDDED SHORTWAVES WILL BRING OCCASIONALLY BREEZY CONDITIONS TO THE
REGION THROUGH THE WEEKEND. TEMPERATURES WILL REMAIN NEAR TO
SLIGHTLY BELOW NORMAL.
&&
.AVIATION...FOR MCCARRAN...LIGHT AND VARIABLE WINDS WILL BEGIN TO
FAVOR A NORTHWEST AND THEN NORTH DIRECTION THROUGH THE MORNING HOURS
AS SPEEDS INCREASE TO AROUND 8-12 KTS. OCCASIONAL GUSTS WILL BE
POSSIBLE. SLIGHT CHANCE OF SHRA OR POSSIBLY AND ISOLATED TS THIS
AFTERNOON/EVENING...HOWEVER CHANCES ARE TOO LOW TO MENTION IN THE
12Z TAF. CIGS GENERALLY EXPECTED TO REMAIN AOA 8K FEET. WINDS ARE
EXPECTED TO CONTINUE TO FAVOR A NORTHERLY DIRECTION THROUGH
WEDNESDAY.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...SHRA/TSRA THIS MORNING OVER MOHAVE COUNTY. EXPECT AT
LEAST SHRA AND POSSIBLY TS ACTIVITY TO SPREAD NORTH AND
EAST...THROUGH THE MORNING. DRY CONDITIONS EXPECTED WEST OF A LINE
FROM KELY-KDRA-KNXP LINE. WINDS EXPECTED TO FAVOR A NORTH DIRECTION
ACROSS MOST OF THE REGION TODAY...WITH SPEEDS 10-20 KTS AND GUSTS
20-30 KTS. SHRA/TSRA ACTIVITY WILL BE CONFINED MAINLY TO MOHAVE
COUNTY WEDNESDAY...GUSTY NORTH WINDS WILL CONTINUE.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION IS NOT EXPECTED
TODAY. HOWEVER...SPOTTERS ARE ENCOURAGED TO REPORT ACCORDING TO
STANDARD OPERATING PROCEDURES.
&&
$$
UPDATE...PADDOCK
PREV DISCUSSION...WOLCOTT
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
600 AM CDT TUE OCT 20 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 216 AM CDT TUE OCT 20 2015
AT 3 AM...A SURFACE LOW WAS LOCATED OVER SOUTHWEST MINNESOTA. A
STATIONARY FRONT EXTENDED EAST FROM THIS LOW FROM FARIBAULT
MINNESOTA TO GREEN BAY WISCONSIN. NORTH OF THIS FRONT TEMPERATURES
WERE IN THE 40S AND 50S. MEANWHILE SOUTH OF THIS FRONT...
TEMPERATURES RANGED FROM THE UPPER 50S TO MID 60S WHICH IS WARMER
THAN OUR NORMAL HIGH TEMPERATURES FOR MID OCTOBER.
FOR THIS AFTERNOON AND EVENING...THE 10.20Z MODELS ARE IN GENERAL
AGREEMENT THAT A SHORT WAVE TROUGH...CURRENTLY LOCATED OVER
EASTERN KANSAS WILL MOVE NORTHEAST INTO EASTERN IOWA THIS
AFTERNOON...AND NORTHERN ILLINOIS AND SOUTHERN WISCONSIN THIS
EVENING. AHEAD OF THIS WAVE...ELEVATED CAPES WILL CLIMB TO AROUND
500 J/KG ACROSS NORTHEAST IOWA AND SOUTHWEST WISCONSIN DURING THE
LATE AFTERNOON AND EVENING. THIS SHOULD BE ENOUGH INSTABILITY FOR
ISOLATED TO SCATTERED SHOWERS TO DEVELOP BETWEEN 20.21Z AND
21.03Z. THE ARW...NMM...AND HRRR COMPOSITE REFLECTIVITY PRODUCT
EVEN HINTS THAT THERE COULD BE SOME ISOLATED THUNDERSTORMS ACROSS
SOUTH CENTRAL AND SOUTHEAST WISCONSIN AND NORTHERN ILLINOIS.
COMPARING THE CURRENT TEMPERATURES TO THE GRIDDED MODEL VALUES...
THE MODELS ARE NOT DOING THAT WELL THIS MORNING ALONG AND SOUTH OF
INTERSTATE 94. THE GRIDDED MINIMUM TEMPERATURES WILL END UP BEING
TOO COLD. PARTLY SUNNY SKIES TODAY WILL ALLOW US TO MIX UP TO
900 MB THIS AFTERNOON. WITH THE GROUND BEING VERY DRY DUE TO THE
LACK OF RAIN DURING THE PAST MONTH...EXPECT THE THERE WILL BE A
SUPER ADIABATIC LAPSE RATE UP TO 900 MB. THIS WILL RESULT IN HIGH
TEMPERATURES IN THESE AREAS CLIMBING INTO THE MID 70S. THIS WILL
BE ABOUT 5 TO 10 DEGREES SHY OF THE RECORDS FOR TODAY. MOST
PLACES HAVE THEIR HIGH TEMPERATURES IN THE LOWER TO MID 80S WHICH
OCCURRED IN 1953...2000...OR 2003.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 216 AM CDT TUE OCT 20 2015
ON WEDNESDAY MORNING...THE 20.00Z MODELS ARE IN GOOD AGREEMENT
THAT A COLD FRONT WILL MOVE THROUGH THE AREA. WITH THE BEST LIFT
AND MOISTURE TRANSPORT BEING TO OUR NORTH AND SOUTHEAST...NOT
SEEING MUCH CHANCE OF PRECIPITATION ALONG IT...SO LOWERED THE RAIN
CHANCES ACROSS WESTERN WISCONSIN TO 20 PERCENT.
FROM FRIDAY INTO SATURDAY...THE MODELS ARE IN GOOD AGREEMENT THAT
THE CLOSED 500 MB LOW...CURRENTLY OVER THE SOUTHWEST UNITED
STATES...WILL LIFT NORTHEAST OUT OF THE CENTRAL AND SOUTHERN
PLAINS ON FRIDAY...MINNESOTA AND WISCONSIN ON FRIDAY NIGHT...AND
THE GREAT LAKES ON SATURDAY. THIS SYSTEM WILL TAP INTO GULF OF
MEXICO AND TROPICAL MOISTURE AS IT MOVES THROUGH THE REGION.
PRECIPITABLE WATER VALUES CLIMB UP TO 1.5 INCHES ON FRIDAY
AFTERNOON /THIS IS 1 TO 2 STANDARD DEVIATIONS ABOVE NORMAL/...AND
THEN QUICKLY DECLINES AS THE COLD FRONT MOVES QUICKLY EAST THROUGH
THE REGION. WITH THE BEST FORCING AND MOISTURE TRANSPORT BEING TO
OUR NORTH AND SOUTHEAST...THE HEAVIEST RAIN MAY MISS OUR AREA.
EVEN IF WE DID SEE SOME HEAVY RAIN...IT SHOULD NOT CREATE ANY
ISSUES BECAUSE IT WILL BE A BRIEF PERIOD AND THAT IT HAS BEEN DRY
SO LONG.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 600 AM CDT TUE OCT 20 2015
SOME HIGH THIN CLOUDS ACROSS PORTIONS OF THE REGION TODAY.
MEANWHILE...WEST-EAST RUNNING SFC BOUNDARY RUNNING FROM SOUTHERN MN
INTO EASTERN WI CONTINUES TO SPARK A FEW -SHRA FROM CENTRAL WI
EASTWARD. WEAK INSTABILITY/WEAK SHORTWAVE ALOFT WERE HELPING THAT
PORTION OF THE BOUNDARY TRIGGER THE -SHRA. MOST MESO MODELS CONTINUE
SOME -SHRA THROUGH THE DAY TO THE EAST. TO THE SOUTH...A SHORTWAVE
TROUGH WAS TRIGGERING -SHRA/TS OVER NORTHERN MO/SOUTHERN IA...WITH
THE HELP OF THE LOW LEVEL JET. MESO MODELS TRACK THIS ACROSS EASTERN
IA AND OVER SOUTHERN WI THIS EVENING...SOUTH/EAST OF THE TAF SITES.
WILL KEEP A DRY FORECAST FOR NOW...ALONG WITH VFR CONDITIONS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...RIECK
AREA FORECAST DISCUSSION...UPDATED
NWS PHOENIX AZ
220 PM MST TUE OCT 20 2015
.UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSIONS.
&&
.SYNOPSIS...
A PERSISTENT AREA OF LOW PRESSURE OVER THE WESTERN UNITED STATES
WILL BRING ELEVATED CHANCES OF SHOWERS AND THUNDERSTORMS TO THE
DESERT SOUTHWEST THROUGH WEDNESDAY. TEMPERATURES WILL COOL OFF WITH
THE LOW PRESSURE SYSTEM. A DRIER AND WARMER AIRMASS WILL RETURN THIS
WEEKEND.
&&
.DISCUSSION...
STORM ACTIVITY STARTED EARLY THIS MORNING AND HAS REMAINED ISOLATED
TO SCATTERED OVER MARICOPA AND LA PAZ COUNTIES...NOT SO MUCH
ELSEWHERE. THE STORMS HAVE PRODUCED LOCALLY HEAVY RAINS WITH FLASH
FLOODING OVER SOME OF THE FOOTHILLS OF FAR NORTHERN METRO PHOENIX.
RUNOFF IN NEW RIVER AND SKUNK CREEK HAS BEEN IMPRESSIVE GIVEN THE
PRECIP GAUGE READINGS AND RADAR ESTIMATES. THESE STORMS HAVE BEEN
ASSOCIATED WITH A SHORT WAVE MOVING THROUGH THE SOUTHERN END OF A
NARROW ELONGATED UPPER TROUGH OVER THE WESTERN STATES. IN ADDITION TO
THE PVA...UPPER DIVERGENCE IS ALSO IN PLAY. THE LATEST RAP INDICATES
THAT THE SHORT WAVE AXIS WILL BE NORTH OF MARICOPA COUNTY BY 20Z.
HOWEVER...IT ALSO INDICATES THAT THERE WILL BE LINGERING UPPER
DIVERGENCE AS WELL AS SOME MODEST VORTICITY AS THE LARGER SCALE
CIRCULATION WITHIN THE SOUTHERN END OF THE TROUGH BECOMES CENTERED
NEAR BLYTHE. A MORE SUBSTANTIAL SHORT WAVE/VORT MAX...CURRENTLY NEAR
THE WEST COAST OF FAR NORTHERN BAJA...WILL TRACK SOUTH OF THE BORDER
THIS AFTERNOON AND EVENING BEFORE AFFECTING MAINLY SOUTHEAST ARIZONA
LATER TONIGHT. EVEN THOUGH THE DYNAMICAL FORCING DECREASES THIS
AFTERNOON THE RAP HOLDS ON TO SIGNIFICANT CAPE. OTHER
MODELS...INCLUDING SREF...TRENDS DOWN THE CAPE AS THE DAY PROGRESSES.
VERTICAL WIND SHEAR LOOKS TO DECREASE AS WELL. THE SHORT OF IT IS
THAT SEVERE POTENTIAL SHOULD BE TRENDING DOWN BUT WE WILL STILL HAVE
ENOUGH GOING ON THAT SHOWER AND THUNDERSTORM CHANCES WILL REMAIN
ELEVATED AND THERE WILL STILL BE ISOLATED SEVERE POTENTIAL INTO THE
EVENING. MADE SOME MINOR TWEAKS TO THE FORECASTS BUT NO MAJOR
CHANGES.
&&
.PREVIOUS DISCUSSION ISSUED 320 AM...
AFTER AN EVENING OF A FEW STRONG THUNDERSTORMS TO THE WEST OF THE
PHOENIX AREA...ISOLATED SHOWERS AND THUNDERSTORMS CONTINUE TO DEVELOP
EARLY THIS MORNING. THIS ACTIVITY IS IN RESPONSE TO A STRONG
SHORTWAVE LOCATED OVER SOUTHWEST ARIZONA WHICH IS EMBEDDED IN A MUCH
BROADER DEEP TROUGH OVER THE WESTERN UNITED STATES. A SERIES OF
SHORTWAVE FEATURES WILL AFFECT THE DESERT SOUTHWEST TODAY INTO
WEDNESDAY BRINGING SEVERAL POTENTIAL ROUNDS OF SHOWERS AND
THUNDERSTORMS TO ARIZONA. THE STRONG TO SEVERE THREAT WILL PERSIST
TODAY...BUT WINDS ALOFT WILL BE DECREASING ACROSS SOUTH-CENTRAL
ARIZONA THIS AFTERNOON...SO BEST CHANCES OF ANY STRONGER STORMS WILL
EXIST MAINLY EAST OF THE PHOENIX METRO AREA. AS OF NOW THINKING THE
SHOWERS AND THUNDERSTORMS CURRENTLY WILL LAST THROUGH AROUND DAYBREAK
WITH A BIT OF A BREAK IN THE ACTIVITY THROUGH EARLY THIS AFTERNOON AS
THE FIRST WAVE PUSHES INTO NORTHERN ARIZONA.
THE FOCUS THEN TURNS TO A STRONGER SHORTWAVE MOVING INTO THE AREA
THIS EVENING INTO TONIGHT. THE LOW CENTER WILL REORIENT ITSELF OVER
SOUTHEAST CALIFORNIA LATER THIS MORNING AND THEN INTO SOUTHERN
ARIZONA FROM THIS EVENING INTO WEDNESDAY. A STRONG PV ANOMALY
ACCOMPANIED BY A 100 KT UPPER LEVEL JET MAX WILL DIVE SOUTHWARD TODAY
ALONG THE BACK EDGE OF THE DEEP TROUGH...HELPING TO STRENGTHEN THE
TROUGH FURTHER. THIS STRONG PV ANOMALY IS FORECAST TO ROUND THE BASE
OF THE TROUGH THIS AFTERNOON THROUGH BAJA AND THE GULF OF CALIFORNIA
AND THEN SWING NORTHWARD INTO SOUTH-CENTRAL ARIZONA THIS EVENING INTO
TONIGHT. AMPLE LIFT FROM THIS FEATURE ALONG WITH MODEST INSTABILITY
SHOULD ALLOW FOR A BROAD AREA OF SHOWERS AND THUNDERSTORMS TO MOVE
THROUGH SOUTH-CENTRAL ARIZONA TONIGHT INTO WEDNESDAY MORNING. AS A
RESULT...I HAVE INCREASED POPS OVER THIS AREA SIGNIFICANTLY.
STEERING FLOW WILL HAVE WEAKENED BY THIS POINT...SO STORM MOVEMENT
WILL SLOW ENOUGH TO PROVIDE A POSSIBILITY OF SOME LOCALIZED FLOODING.
FOR WEDNESDAY...THE LOW CENTER WILL REMAIN FAIRLY STATIONARY OVER
SOUTHERN ARIZONA WITH AN AREA OF FOCUSED VERTICAL ASCENT FROM PHOENIX
EASTWARD. DRIER AIR WILL BEGIN TO GET DRAWN IN FROM THE NORTH DURING
THE DAY WEDNESDAY...SO INSTABILITY VALUES WILL DROP LEAVING MAINLY A
GOOD SHOT OF SHOWERS AND A FEW THUNDERSTORMS. CHANCES FOR SHOWERS
WILL DIMINISH BY WEDNESDAY EVENING AND SHOULD MAINLY BE OVER HIGHER
TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH WEDNESDAY WILL
SEEM RATHER COOL WITH HIGHS ONLY IN THE UPPER 70S TO LOWER 80S OVER
THE SOUTH-CENTRAL DESERTS...BUT MORE LIKE THE MIDDLE TO UPPER 80S
ACROSS OUR WESTERN ZONES.
THURSDAY AND FRIDAY WILL BE A TRANSITION PERIOD AS THIS DEEP LOW
FINALLY MOVES EASTWARD ALLOWING FOR MUCH DRIER CONDITIONS AND A
WARMING TREND. THE SYNOPTIC FLOW WILL BRING IN A WEAK RIDGE BY FRIDAY
NIGHT FOLLOWED BY MORE OF A ZONAL TYPE FLOW PATTERN THROUGH THE
WEEKEND. RAIN CHANCES WILL END ACROSS MOST OF THE AREA ON THURSDAY
AND THE REGION SHOULD STAY DRY AT LEAST THROUGH THE MIDDLE OF NEXT
WEEK. TEMPERATURES WILL CLIMB BACK TO NEAR NORMALS BY FRIDAY AND THEN
EVEN SLIGHTLY ABOVE NORMAL FOR THE WEEKEND INTO NEXT WEEK.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL... ACTIVE AND
UNSETTLED WEATHER WILL CONTINUE OVER THE CENTRAL DESERTS THIS
AFTERNOON...OVENIGHT TONIGHT AND INTO THE DAY ON WEDNESDAY...AS A
STRONG UPPER LOW MOVES ACROSS THE AREA. AS OF 2 PM MOST OF THE
STRONG STORMS HAD ENDED AND MOVED EAST OF THE TERMINALS FOLLOWING A
SHORT WAVE PASSAGE ALTHOUGH ISOLATED SHOWERS/STORMS MAY OCCUR THIS
AFTERNOON INTO THE EVENING. MOST CIGS SHOULD STAY AOA 6K FEET.
REDEVELOPEMENT OF SHOWERS IS LIKELY BY MID EVENING WITH BKN-OVC CIGS
EXPECTED INTO THE MORNING HOURS WED...WITH BASES GENLY 7-10K FEET.
GREATER AREAL COVERAGE OVERNIGHT INTO WED WILL BE SHOWERS WITH
THUNDERSTORMS ON THE ISOLATED SIDE. THUS...AFTER 02Z-04Z WE WILL GO
WITH PREDOMINANT -SHRA...AND KEEP VCTS TO COVER THUNDERSTORM
THREATS. WINDS WILL TEND TO BE ON THE LIGHT SIDE AND VARIABLE
SIDE...BUT STRONGER AND GUSTY NEAR ANY STORM THAT DEVELOPS.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
MOST OF THE WEATHER ASSOCIATED WITH THE PASSING LOW SHOULD STAY IN
ARIZONA...BUT KBLH MAY BE ON THE FRINGES OF POSSIBLE WEATHER AND
THUS WE WILL KEEP -SHRA ALONG WITH VCTS IN THE FORECAST THIS
AFTERNOON AND MOST OF THE NIGHT TONIGHT. CIGS SHOULD STAY MOSTLY
ABOVE 7K FEET. NO WEATHER EXPECTED AT KIPL...JUST FEW-SCT HIGHER
BASED CU OR MID DECKS WITH BASES MOSTLY 8-10K FEET. WINDS WILL BE ON
THE LIGHT SIDE FAVORING WEST/NORTHWEST AT KIPL AND NORTH AT KBLH.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...FRIDAY THROUGH TUESDAY...LOW PRESSURE WILL MIGRATE
EAST OF THE REGION THURSDAY. IN ITS WAKE...A SLOW WARMING TREND IS
EXPECTED THROUGH THE WEEKEND. ANOTHER WEAK LOW PRESSURE SYSTEM WILL
MOVE THROUGH FRIDAY...BUT IS NOT EXPECTED TO PRODUCE ANY SENSIBLE
WEATHER IMPACTS. AFTERNOON HUMIDITY VALUES IN THE 25 TO 45 PERCENT
RANGE EARLIER IN THE WEEK WILL FALL INTO THE 20 TO 35 PERCENT RANGE
BY THE WEEKEND. OVERNIGHT RECOVERY WILL BE GOOD TO EXCELLENT.
TEMPERATURES WILL STEADILY CLIMB...STARTING NEAR SEASONAL NORMALS ON
FRIDAY AND CLIMBING ABOVE NORMAL EACH DAY WITH WARMER DESERTS
CLIMBING INTO THE LOW 90S BY THE END OF THE WEEKEND. WINDS WILL BE
LIGHT THROUGH THE PERIOD...FAVORING NORMAL DIURNAL TENDENCIES WITH A
FEW AFTERNOON BREEZES POSSIBLE.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT BASED ON STANDARD OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ
PREVIOUS DISCUSSION...KUHLMAN
AVIATION...CB
FIRE WEATHER...HIRSCH/CB
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
923 AM MST TUE OCT 20 2015
.SYNOPSIS...
A PERSISTENT AREA OF LOW PRESSURE OVER THE WESTERN UNITED STATES
WILL BRING ELEVATED CHANCES OF SHOWERS AND THUNDERSTORMS TO THE
DESERT SOUTHWEST THROUGH WEDNESDAY. TEMPERATURES WILL COOL OFF WITH
THE LOW PRESSURE SYSTEM. A DRIER AND WARMER AIRMASS WILL RETURN THIS
WEEKEND.
&&
.DISCUSSION...
STORM ACTIVITY STARTED EARLY THIS MORNING AND HAS REMAINED ISOLATED
TO SCATTERED OVER MARICOPA AND LA PAZ COUNTIES...NOT SO MUCH
ELSEWHERE. THE STORMS HAVE PRODUCED LOCALLY HEAVY RAINS WITH FLASH
FLOODING OVER SOME OF THE FOOTHILLS OF FAR NORTHERN METRO PHOENIX.
RUNOFF IN NEW RIVER AND SKUNK CREEK HAS BEEN IMPRESSIVE GIVEN THE
PRECIP GAUGE READINGS AND RADAR ESTIMATES. THESE STORMS HAVE BEEN
ASSOCIATED WITH A SHORT WAVE MOVING THROUGH THE SOUTHERN END OF A
NARROW ELONGATED UPPER TROUGH OVER THE WESTERN STATES. IN ADDITION TO
THE PVA...UPPER DIVERGENCE IS ALSO IN PLAY. THE LATEST RAP INDICATES
THAT THE SHORT WAVE AXIS WILL BE NORTH OF MARICOPA COUNTY BY 20Z.
HOWEVER...IT ALSO INDICATES THAT THERE WILL BE LINGERING UPPER
DIVERGENCE AS WELL AS SOME MODEST VORTICITY AS THE LARGER SCALE
CIRCULATION WITHIN THE SOUTHERN END OF THE TROUGH BECOMES CENTERED
NEAR BLYTHE. A MORE SUBSTANTIAL SHORT WAVE/VORT MAX...CURRENTLY NEAR
THE WEST COAST OF FAR NORTHERN BAJA...WILL TRACK SOUTH OF THE BORDER
THIS AFTERNOON AND EVENING BEFORE AFFECTING MAINLY SOUTHEAST ARIZONA
LATER TONIGHT. EVEN THOUGH THE DYNAMICAL FORCING DECREASES THIS
AFTERNOON THE RAP HOLDS ON TO SIGNIFICANT CAPE. OTHER
MODELS...INCLUDING SREF...TRENDS DOWN THE CAPE AS THE DAY PROGRESSES.
VERTICAL WIND SHEAR LOOKS TO DECREASE AS WELL. THE SHORT OF IT IS
THAT SEVERE POTENTIAL SHOULD BE TRENDING DOWN BUT WE WILL STILL HAVE
ENOUGH GOING ON THAT SHOWER AND THUNDERSTORM CHANCES WILL REMAIN
ELEVATED AND THERE WILL STILL BE ISOLATED SEVERE POTENTIAL INTO THE
EVENING. MADE SOME MINOR TWEAKS TO THE FORECASTS BUT NO MAJOR
CHANGES.
&&
.PREVIOUS DISCUSSION ISSUED 320 AM...
AFTER AN EVENING OF A FEW STRONG THUNDERSTORMS TO THE WEST OF THE
PHOENIX AREA...ISOLATED SHOWERS AND THUNDERSTORMS CONTINUE TO DEVELOP
EARLY THIS MORNING. THIS ACTIVITY IS IN RESPONSE TO A STRONG
SHORTWAVE LOCATED OVER SOUTHWEST ARIZONA WHICH IS EMBEDDED IN A MUCH
BROADER DEEP TROUGH OVER THE WESTERN UNITED STATES. A SERIES OF
SHORTWAVE FEATURES WILL AFFECT THE DESERT SOUTHWEST TODAY INTO
WEDNESDAY BRINGING SEVERAL POTENTIAL ROUNDS OF SHOWERS AND
THUNDERSTORMS TO ARIZONA. THE STRONG TO SEVERE THREAT WILL PERSIST
TODAY...BUT WINDS ALOFT WILL BE DECREASING ACROSS SOUTH-CENTRAL
ARIZONA THIS AFTERNOON...SO BEST CHANCES OF ANY STRONGER STORMS WILL
EXIST MAINLY EAST OF THE PHOENIX METRO AREA. AS OF NOW THINKING THE
SHOWERS AND THUNDERSTORMS CURRENTLY WILL LAST THROUGH AROUND DAYBREAK
WITH A BIT OF A BREAK IN THE ACTIVITY THROUGH EARLY THIS AFTERNOON AS
THE FIRST WAVE PUSHES INTO NORTHERN ARIZONA.
THE FOCUS THEN TURNS TO A STRONGER SHORTWAVE MOVING INTO THE AREA
THIS EVENING INTO TONIGHT. THE LOW CENTER WILL REORIENT ITSELF OVER
SOUTHEAST CALIFORNIA LATER THIS MORNING AND THEN INTO SOUTHERN
ARIZONA FROM THIS EVENING INTO WEDNESDAY. A STRONG PV ANOMALY
ACCOMPANIED BY A 100 KT UPPER LEVEL JET MAX WILL DIVE SOUTHWARD TODAY
ALONG THE BACK EDGE OF THE DEEP TROUGH...HELPING TO STRENGTHEN THE
TROUGH FURTHER. THIS STRONG PV ANOMALY IS FORECAST TO ROUND THE BASE
OF THE TROUGH THIS AFTERNOON THROUGH BAJA AND THE GULF OF CALIFORNIA
AND THEN SWING NORTHWARD INTO SOUTH-CENTRAL ARIZONA THIS EVENING INTO
TONIGHT. AMPLE LIFT FROM THIS FEATURE ALONG WITH MODEST INSTABILITY
SHOULD ALLOW FOR A BROAD AREA OF SHOWERS AND THUNDERSTORMS TO MOVE
THROUGH SOUTH-CENTRAL ARIZONA TONIGHT INTO WEDNESDAY MORNING. AS A
RESULT...I HAVE INCREASED POPS OVER THIS AREA SIGNIFICANTLY.
STEERING FLOW WILL HAVE WEAKENED BY THIS POINT...SO STORM MOVEMENT
WILL SLOW ENOUGH TO PROVIDE A POSSIBILITY OF SOME LOCALIZED FLOODING.
FOR WEDNESDAY...THE LOW CENTER WILL REMAIN FAIRLY STATIONARY OVER
SOUTHERN ARIZONA WITH AN AREA OF FOCUSED VERTICAL ASCENT FROM PHOENIX
EASTWARD. DRIER AIR WILL BEGIN TO GET DRAWN IN FROM THE NORTH DURING
THE DAY WEDNESDAY...SO INSTABILITY VALUES WILL DROP LEAVING MAINLY A
GOOD SHOT OF SHOWERS AND A FEW THUNDERSTORMS. CHANCES FOR SHOWERS
WILL DIMINISH BY WEDNESDAY EVENING AND SHOULD MAINLY BE OVER HIGHER
TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH WEDNESDAY WILL
SEEM RATHER COOL WITH HIGHS ONLY IN THE UPPER 70S TO LOWER 80S OVER
THE SOUTH-CENTRAL DESERTS...BUT MORE LIKE THE MIDDLE TO UPPER 80S
ACROSS OUR WESTERN ZONES.
THURSDAY AND FRIDAY WILL BE A TRANSITION PERIOD AS THIS DEEP LOW
FINALLY MOVES EASTWARD ALLOWING FOR MUCH DRIER CONDITIONS AND A
WARMING TREND. THE SYNOPTIC FLOW WILL BRING IN A WEAK RIDGE BY FRIDAY
NIGHT FOLLOWED BY MORE OF A ZONAL TYPE FLOW PATTERN THROUGH THE
WEEKEND. RAIN CHANCES WILL END ACROSS MOST OF THE AREA ON THURSDAY
AND THE REGION SHOULD STAY DRY AT LEAST THROUGH THE MIDDLE OF NEXT
WEEK. TEMPERATURES WILL CLIMB BACK TO NEAR NORMALS BY FRIDAY AND THEN
EVEN SLIGHTLY ABOVE NORMAL FOR THE WEEKEND INTO NEXT WEEK.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
COMPLICATED FORECAST TODAY AND TONIGHT. STORMS CONTINUE TO RACE
NORTHWARD AND ALL PHOENIX TERMINALS SHOULD SEE A LITTLE BREAK IN THE
ACTIVITY THROUGH DAYBREAK. HOWEVER ANOTHER ROUND OF SCATTERED SHOWERS
IS EXPECTED TO MOVE INTO THE AREA BY MID MORNING /ALREADY DEVELOPING
ACROSS YUMA/SW MARICOPA COUNTIES/ AND WILL LIKELY AFFECT ALL PHOENIX
TAF SITES. ADDITIONAL SCATTERED SHOWERS AND STORMS ARE EXPECTED THIS
AFTERNOON AND EVENING. QUITE A BIT OF UNCERTAINTY WITH RESPECT TO
EXACT TIMING OF SHOWERS/STORMS BUT IT WOULD APPEAR CHANCES WILL
GRADUALLY INCREASE THIS AFTERNOON AND EVENING AND REACH THEIR PEAK
LATE TONIGHT INTO EARLY WEDNESDAY MORNING.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
UPPER LOW SHOULD ALLOW FOR STORMS TO DEVELOP LATER THIS AFTERNOON AND
EVENING AND PRIMARILY AFFECT ARIZONA...ALTHOUGH BLH MAY SEE SOME
STORM ACTIVITY. SHOULD BE TOO DRY AT IPL TO SUPPORT STORM
DEVELOPMENT.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER... THURSDAY THROUGH MONDAY...
LOW PRESSURE WILL MIGRATE EAST OF THE REGION THURSDAY. IN ITS
WAKE...A SLOW WARMING TREND IS EXPECTED THROUGH THE WEEKEND. ANOTHER
WEAK LOW PRESSURE SYSTEM WILL MOVE THROUGH FRIDAY...BUT IS NOT
EXPECTED TO PRODUCE ANY SENSIBLE WEATHER IMPACTS. AFTERNOON HUMIDITY
VALUES IN THE 25 TO 45 PERCENT RANGE EARLIER IN THE WEEK WILL FALL
INTO THE 20 TO 35 PERCENT RANGE BY THE WEEKEND. OVERNIGHT RECOVERY
WILL BE GOOD TO EXCELLENT.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT BASED ON STANDARD OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ
PREVIOUS DISCUSSION...KUHLMAN
AVIATION...LEINS
FIRE WEATHER...HIRSCH
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
449 PM MDT TUE OCT 20 2015
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 244 PM MDT TUE OCT 20 2015
THE HRRR HAS BEEN PERFORMING WELL IN THE SHORT TERM AND SHOWS A
SIGNIFICANT WAVE LIFTING THROUGH THE FOUR CORNERS LATE THIS AFTERNOON
THEN WEAKENING NORTH OF THE SAN JUANS THIS EVENING TO ALONG THE
I-70 CORRIDOR AROUND MIDNIGHT. LIGHTNING...HEAVY RAIN...HAIL...AND
WIND GUSTS ARE EXPECTED ALONG THIS LINE THIS AFTERNOON AND
EVENING. WITH SNOW LEVELS REMAINING AT OR BELOW 10000 FT
TONIGHT...SIGNIFICANT SNOW ACCUMULATIONS ARE EXPECTED IN THE SW
SAN JUANS OVERNIGHT. UP TO 5 INCHES OF ACCUMULATION ARE POSSIBLE
THERE WITH LIGHTER ACCUMULATIONS IN THE REMAINDER OF THE MOUNTAINS
SOUTH OF I-70. AN ADVISORY HAS BEEN ISSUED TO ACCOUNT FOR THIS
SNOWFALL.
BY DAYBREAK WEDNESDAY...THE CULPRIT FOR ALL THIS WEATHER..A CLOSED
LOW...WILL HAVE SHIFTED TO SRN AZ WHILE SPOKES OF ENERGY CONTINUE
TO ROTATE AROUND IT. MODEL DIFFERENCES ALREADY POP UP BTWN NAM AND
GFS/EC WITH NAM HIGHLIGHTING SOME HEAVIER PRECIP FOR OUR NRN TIER
ZONES WHILE GFS/EC FAVOR AREAS SOUTH. H7 WINDS FOUND IN NAM OVER
THIS AREA ARE IN THE 30 TO 35MPH RANGE WHILE THOSE IN OTHER MODELS
ARE ONLY ABOUT 10 MPH. NAM MAY BE PUTTING TOO MUCH EMPHASIS ON
THESE WINDS BRINGING MORE PRECIP INTO THAT AREA. WITH CONFIDENCE
NOT ESPECIALLY HIGH ATTM...WILL KEEP CHC TO SCHC POPS GOING FOR
MUCH OF THE FORECAST AREA WITH REALIZATION THAT SOME AREAS WILL
PROBABLY NOT SEE MUCH OR ANY PRECIP WHILE OTHERS WILL. LATER
SHIFTS CAN REEVALUATE AND MAKE CHANGES AS NEEDED ONCE MODELS AGREE
ON THE FINER DETAILS. FOR WED NIGHT...ALL MODELS AGREE THAT SAN
JUANS WILL SEE AN UPTICK IN PRECIP WITH ELEVATIONS ABOVE 10K FEET
LIKELY SEEING SOME SNOW...AN INCH OR THREE. OTHER AREAS WILL SEE
CLOUDS AND SHOWERY TYPE PRECIP. WILL SEE HOW MUCH SNOW THOSE AREAS
RECEIVE TONIGHT BEFORE CONSIDERING ANY HIGHLIGHTS FOR WEDNESDAY
NIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 244 PM MDT TUE OCT 20 2015
THE LOW FINALLY OPENS UP THURSDAY AND LIFTS TO THE NORTHEAST. MORE
SHOWERS AND STORMS REMAIN POSSIBLE AS THE COLD CORE MOVES OVERHEAD
CAUSING AN INCREASE IN INSTABILITY WHILE PWATS STILL REMAIN HIGH.
ALL HIGHER TERRAIN LOOKS FAVORED IN THE MODELS BUT SOME VALLEYS
WILL ALSO SEE SOME PRECIP. NEXT FORECAST CHALLENGE LOOKS TO BE
THURSDAY NIGHT INTO FRIDAY MORNING AS WINDS SHIFT TO THE WEST AND
NORTHWEST USHERING IN COOLER AIR. MODELS HIGHLIGHT A POST FRONTAL
WAVE MOVING OVER THE AREA THURSDAY EVENING AND WITH COOLER AIR IN
PLACE...SOME SNOW ACCUMULATION...2 TO 4 INCHES...LOOKS POSSIBLE
ABOVE 9K FEET OR SO. THE FLAT TOPS AND NRN MTNS LOOK FAVORED
THOUGH THE CENTRAL AND SAN JUANS WILL ALSO SEE SOME SOME
SNOW...AROUND 1 TO 3 INCHES.
FRIDAY REMAINS UNSETTLED AS A WEAK IMPULSE MOVES THROUGH THE AREA
BRINGING MORE ISOLD TO SCTD SHOWERS THOUGH MINIMAL UPPER LEVEL
SUPPORT SHOULD KEEP INTENSITY AND COVERAGE LOWER THAN SEEN
LATELY.
FLOW STARTS TO BECOME MORE ZONAL SATURDAY AND THIS FLOW PERSISTS
THROUGH MONDAY. NO PRECIP IS EXPECTED AT THIS TIME THOUGH SOME
HIGH CLOUDS WILL MOVE OVERHEAD. TEMPS WILL RISE ABOVE NORMAL
DURING THIS PERIOD BUT NOTHING TOO EXCEPTIONAL. PRECIP CHANCES
BEGIN TO INCREASE MONDAY EVENING INTO TUESDAY AS ANOTHER WEAK WAVE
MOVES ACROSS THE AREA THOUGH...AT THIS POINT...THE FRONT RANGE
LOOKS FAVORED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 449 PM MDT TUE OCT 20 2015
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS EASTERN
UTAH AND WESTERN COLORADO THROUGH WEDNESDAY. STRONG STORMS ARE
POSSIBLE THIS EVENING FOR AREAS SOUTH OF THE I-70 CORRIDOR. A FEW
STORMS WILL BE STRONG...CAPABLE OF PRODUCING HAIL UP TO 1 INCH IN
DIAMETER AND GUSTY OUTFLOW WINDS IN EXCESS OF 45 KTS. CIGS WILL
BRIEFLY DROP BELOW MVFR THRESHOLDS AS SHOWERS MOVE THROUGH. SNOW
LEVELS LOOK TO REMAIN AOA 10K THROUGH THIS OPERATIONAL PERIOD. IFR
OR LIFR CONDITIONS ARE MOST LIKELY FOR KDRO AND KTEX FROM 21Z-00Z
...KMTJ...KCNY...KMTJ...KASE AND KEGE FROM 00Z-06Z. MOUNTAIN TOPS
WILL BE OBSCURED AT TIMES THROUGH THE PERIOD.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY FROM 8 PM THIS EVENING TO 9 AM MDT
WEDNESDAY FOR COZ019.
UT...FLASH FLOOD WATCH UNTIL 9 PM MDT THIS EVENING FOR UTZ022-027>029.
&&
$$
SHORT TERM...JOE/TGR
LONG TERM...TGR
AVIATION...TGJT
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
303 PM MDT TUE OCT 20 2015
RESENT TO FIX TYPO.
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 244 PM MDT TUE OCT 20 2015
THE HRRR HAS BEEN PERFORMING WELL IN THE SHORT TERM AND SHOWS A
SIGNIFICANT WAVE LIFTING THROUGH THE FOUR CORNERS LATE THIS AFTERNOON
THEN WEAKENING NORTH OF THE SAN JUANS THIS EVENING TO ALONG THE
I-70 CORRIDOR AROUND MIDNIGHT. LIGHTNING...HEAVY RAIN...HAIL...AND
WIND GUSTS ARE EXPECTED ALONG THIS LINE THIS AFTERNOON AND
EVENING. WITH SNOW LEVELS REMAINING AT OR BELOW 10000 FT
TONIGHT...SIGNIFICANT SNOW ACCUMULATIONS ARE EXPECTED IN THE SW
SAN JUANS OVERNIGHT. UP TO 5 INCHES OF ACCUMULATION ARE POSSIBLE
THERE WITH LIGHTER ACCUMULATIONS IN THE REMAINDER OF THE MOUNTAINS
SOUTH OF I-70. AN ADVISORY HAS BEEN ISSUED TO ACCOUNT FOR THIS
SNOWFALL.
BY DAYBREAK WEDNESDAY...THE CULPRIT FOR ALL THIS WEATHER..A CLOSED
LOW...WILL HAVE SHIFTED TO SRN AZ WHILE SPOKES OF ENERGY CONTINUE
TO ROTATE AROUND IT. MODEL DIFFERENCES ALREADY POP UP BTWN NAM AND
GFS/EC WITH NAM HIGHLIGHTING SOME HEAVIER PRECIP FOR OUR NRN TIER
ZONES WHILE GFS/EC FAVOR AREAS SOUTH. H7 WINDS FOUND IN NAM OVER
THIS AREA ARE IN THE 30 TO 35MPH RANGE WHILE THOSE IN OTHER MODELS
ARE ONLY ABOUT 10 MPH. NAM MAY BE PUTTING TOO MUCH EMPHASIS ON
THESE WINDS BRINGING MORE PRECIP INTO THAT AREA. WITH CONFIDENCE
NOT ESPECIALLY HIGH ATTM...WILL KEEP CHC TO SCHC POPS GOING FOR
MUCH OF THE FORECAST AREA WITH REALIZATION THAT SOME AREAS WILL
PROBABLY NOT SEE MUCH OR ANY PRECIP WHILE OTHERS WILL. LATER
SHIFTS CAN REEVALUATE AND MAKE CHANGES AS NEEDED ONCE MODELS AGREE
ON THE FINER DETAILS. FOR WED NIGHT...ALL MODELS AGREE THAT SAN
JUANS WILL SEE AN UPTICK IN PRECIP WITH ELEVATIONS ABOVE 10K FEET
LIKELY SEEING SOME SNOW...AN INCH OR THREE. OTHER AREAS WILL SEE
CLOUDS AND SHOWERY TYPE PRECIP. WILL SEE HOW MUCH SNOW THOSE AREAS
RECEIVE TONIGHT BEFORE CONSIDERING ANY HIGHLIGHTS FOR WEDNESDAY
NIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 244 PM MDT TUE OCT 20 2015
THE LOW FINALLY OPENS UP THURSDAY AND LIFTS TO THE NORTHEAST. MORE
SHOWERS AND STORMS REMAIN POSSIBLE AS THE COLD CORE MOVES OVERHEAD
CAUSING AN INCREASE IN INSTABILITY WHILE PWATS STILL REMAIN HIGH.
ALL HIGHER TERRAIN LOOKS FAVORED IN THE MODELS BUT SOME VALLEYS
WILL ALSO SEE SOME PRECIP. NEXT FORECAST CHALLENGE LOOKS TO BE
THURDSAY NIGHT INTO FRIDAY MORNING AS WINDS SHIFT TO THE WEST AND
NORTHWEST USHERING IN COOLER AIR. MODELS HIGHLIGHT A POST FRONTAL
WAVE MOVING OVER THE AREA THURSDAY EVENING AND WITH COOLER AIR IN
PLACE...SOME SNOW ACCUMULATION...2 TO 4 INCHES...LOOKS POSSIBLE
ABOVE 9K FEET OR SO. THE FLAT TOPS AND NRN MTNS LOOK FAVORED
THOUGH THE CENTRAL AND SAN JUANS WILL ALSO SEE SOME SOME
SNOW...AROUND 1 TO 3 INCHES.
FRIDAY REMAINS UNSETTLED AS A WEAK IMPULSE MOVES THROUGH THE AREA
BRINGING MORE ISOLD TO SCTD SHOWERS THOUGH MINIMAL UPPER LEVEL
SUPPORT SHOULD KEEP INTENSITY AND COVERAGE LOWER THAN SEEN
LATELY.
FLOW STARTS TO BECOME MORE ZONAL SATURDAY AND THIS FLOW PERSISTS
THROUGH MONDAY. NO PRECIP IS EXPECTED AT THIS TIME THOUGH SOME
HIGH CLOUDS WILL MOVE OVERHEAD. TEMPS WILL RISE ABOVE NORMAL
DURING THIS PERIOD BUT NOTHING TOO EXCEPTIONAL. PRECIP CHANCES
BEGIN TO INCREASE MONDAY EVENING INTO TUESDAY AS ANOTHER WEAK WAVE
MOVES ACROSS THE AREA THOUGH...AT THIS POINT...THE FRONT RANGE
LOOKS FAVORED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1215 PM MDT TUE OCT 20 2015
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS EASTERN
UTAH AND WESTERN COLORADO THROUGH WEDNESDAY. STRONG STORMS ARE
POSSIBLE THIS AFTERNOON AND EVENING FOR AREA UP TO THE I-70
CORRIDOR. A FEW STORMS WILL BE STRONG AND CAPABLE OF PRODUCING
HAIL UP TO 1 INCH IN DIAMETER AND GUSTY OUTFLOW WINDS IN EXCESS OF
45 KTS. CIGS WILL BRIEFLY DROP BELOW MVFR THRESHOLDS AS SHOWERS
MOVE THROUGH. SNOW LEVELS LOOK TO REMAIN AOA 10K THROUGH THIS
OPERATIONAL PERIOD. IFR OR LIFR CONDITIONS ARE MOST LIKELY FOR
KDRO KTEX FROM 21Z-00Z...KMTJ KCNY KMTJ KASE KEGE FROM 00Z-06Z.
MOUNTAIN TOPS WILL BE OBSCURED AT TIMES THROUGH THE PERIOD.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY FROM 8 PM THIS EVENING TO 9 AM MDT
WEDNESDAY FOR COZ019.
UT...FLASH FLOOD WATCH UNTIL 9 PM MDT THIS EVENING FOR UTZ022-027>029.
&&
$$
SHORT TERM...JOE/TGR
LONG TERM...TGR
AVIATION...JOE
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
247 PM MDT TUE OCT 20 2015
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 244 PM MDT TUE OCT 20 2015
THE HRRR HAS BEEN PERFORMING WELL IN THE SHORT TERM AND SHOWS A
SIGNIFICANT WAVE LIFTING THROUGH THE FOUR CORNERS LATE THIS AFTERNOON
THEN WEAKENING NORTH OF THE SAN JUANS THIS EVENING TO ALONG THE
I-70 CORRIDOR AROUND MIDNIGHT. LIGHTNING...HEAVY RAIN...HAIL...AND
WIND GUSTS ARE EXPECTED ALONG THIS LINE THIS AFTERNOON AND
EVENING. WITH SNOW LEVELS REMAINING AT OR BELOW 10000 FT
TONIGHT...SIGNIFICANT SNOW ACCUMULATIONS ARE EXPECTED IN THE SW
SAN JUANS OVERNIGHT. UP TO 5 INCHES OF ACCUMULATION ARE POSSIBLE
THERE WITH LIGHTER ACCUMULATIONS IN THE REMAINDER OF THE MOUNTAINS
SOUTH OF I-70. AN ADVISORY HAS BEEN ISSUED TO ACCOUNT FOR THIS
SNOWFALL.
BY DAYBREAK WEDNESDAY...THE CULPRIT FOR ALL THIS WEATHER..A CLOSED
LOW...WILL HAVE SHIFTED TO SRN AZ WHILE SPOKES OF ENERGY CONTINUE
TO ROTATE AROUND IT. MODEL DIFFERENCES ALREADY POP UP BTWN NAM AND
GFS/EC WITH NAM HIGHLIGHTING SOME HEAVIER PRECIP FOR OUR NRN TIER
ZONES WHILE GFS/EC FAVOR AREAS SOUTH. H7 WINDS FOUND IN NAM OVER
THIS AREA ARE IN THE 30 TO 35MPH RANGE WHILE THOSE IN OTHER MODELS
ARE ONLY ABOUT 10 MPH. NAM MAY BE PUTTING TOO MUCH EMPHASIS ON
THESE WINDS BRINGING MORE PRECIP INTO THAT AREA. WITH CONFIDENCE
NOT ESPECIALLY HIGH ATTM...WILL KEEP CHC TO SCHC POPS GOING FOR
MUCH OF THE FORECAST AREA WITH REALIZATION THAT SOME AREAS WILL
PROBABLY NOT SEE MUCH OR ANY PRECIP WHILE OTHERS WILL. LATER
SHIFTS CAN REEVALUATE AND MAKE CHANGES AS NEEDED ONCE MODELS AGREE
ON THE FINER DETAILS. FOR WED NIGHT...ALL MODELS AGREE THAT SAN
JUANS WILL SEE AN UPTICK IN PRECIP WITH ELEVATIONS ABOVE 10K FEET
LIKELY SEEING SOME SNOW...AN INCH OR THREE. OTHER AREAS WILL SEE
CLOUDS AND SHOWERY TYPE PRECIP. WILL SEE HOW MUCH SNOW THOSE AREAS
RECEIVE TONIGHT BEFORE CONSIDERING ANY HIGHLIGHTS FOR WEDNESDAY
NIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 244 PM MDT TUE OCT 20 2015
THE LOW FINALLY OPENS UP THURSDAY AND LIFTS TO THE NORTHEAST. MORE
SHOWERS AND STORMS REMAIN POSSIBLE AS THE COLD CORE MOVES OVERHEAD
CAUSING AN INCREASE IN INSTABILITY WHILE PWATS STILL REMAIN HIGH.
ALL HIGHER TERRAIN LOOKS FAVORED IN THE MODELS BUT SOME VALLEYS
WILL ALSO SEE SOME PRECIP. NEXT FORECAST CHALLENGE LOOKS TO BE
THURDSAY NIGHT INTO FRIDAY MORNING AS WINDS SHIFT TO THE WEST AND
NORTHWEST USHERING IN COOLER AIR. MODELS HIGHLIGHT A POST FRONTAL
WAVE MOVING OVER THE AREA THURSDAY EVENING AND WITH COOLER AIR IN
PLACE...SOME SNOW ACCUMULATION...2 TO 4 INCHES...LOOKS POSSIBLE
ABOVE 9K FEET OR SO. THE FLAT TOPS AND NRN MTNS LOOK FAVORED
THOUGH THE CENTRAL AND SAN JUANS WILL ALSO SEE SOME SOME
SNOW...AROUND 1 TO 3 INCHES.
FRIDAY REMAINS UNSETTLED AS A WEAK IMPULSE MOVES THROUGH THE AREA
BRINGING MORE ISOLD TO SCTD SHOWERS THOUGH MINIMAL UPPER LEVEL
SUPPORT SHOULD KEEP INTENSITY AND COVERAGE LOWER THAN SEEN
LATELY.
FLOW STARTS TO BECOME MORE ZONAL SATURDAY AND THIS FLOW PERSISTS
THROUGH MONDAY. NO PRECIP IS EXPECTED AT THIS TIME THOUGH SOME
HIGH CLOUDS WILL MOVE OVERHEAD. TEMPS WILL RISE ABOVE NORMAL
DURING THIS PERIOD BUT NOTHING TOO EXCEPTIONAL. PRECIP CHANCES
BEGIN TO INCREASE MONDAY EVENING INTO TUESDAY AS ANOTHER WEAK WAVE
MOVES ACROSS THE AREA THOUGH...AT THIS POINT...THE FRONT RANGE
LOOKS FAVORED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1215 PM MDT TUE OCT 20 2015
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS EASTERN
UTAH AND WESTERN COLORADO THROUGH WEDNESDAY. STRONG STORMS ARE
POSSIBLE THIS AFTERNOON AND EVENING FOR AREA UP TO THE I-70
CORRIDOR. A FEW STORMS WILL BE STRONG AND CAPABLE OF PRODUCING
HAIL UP TO 1 INCH IN DIAMETER AND GUSTY OUTFLOW WINDS IN EXCESS OF
45 KTS. CIGS WILL BRIEFLY DROP BELOW MVFR THRESHOLDS AS SHOWERS
MOVE THROUGH. SNOW LEVELS LOOK TO REMAIN AOA 10K THROUGH THIS
OPERATIONAL PERIOD. IFR OR LIFR CONDITIONS ARE MOST LIKELY FOR
KDRO KTEX FROM 21Z-00Z...KMTJ KCNY KMTJ KASE KEGE FROM 00Z-06Z.
MOUNTAIN TOPS WILL BE OBSCURED AT TIMES THROUGH THE PERIOD.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY FROM 8 PM THIS EVENING TO 9 AM MDT
WEDNESDAY FOR COZ019.
UT...FLASH FLOOD WATCH UNTIL 9 PM MDT THIS EVENING FOR UTZ022-027>029.
&&
$$
SHORT TERM...JOE/JOE/TGR
LONG TERM...TGR
AVIATION...JOE
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1222 PM MDT TUE OCT 20 2015
.UPDATE...
ISSUED AT 1215 PM MDT TUE OCT 20 2015
THE UPPER LOW CONTINUES TO SPIN WITH SIGNIFICANT ENERGY DIGGING
THE BOTTOM OF THE LOW INTO THE NORTHERN BAJA. STRONG DIVERGENT
PORTION OF THE LOW REMAINS WELL SOUTH OF THE FOUR CORNERS FOR AN
INTERESTING WEATHER DAY ACROSS THE DESERT SW. LOCALLY THE SOUTHERN
PORTION OF THE FORECAST AREA REMAINS PRIMED FOR HAIL WITH THE WET
BULB ZERO LEVEL BELOW 11KFT...MOISTURE IS WELL ABOVE NORMAL...AND
INSTABILITY IS FAIR WITH SOME WEAK COLD ADVECTION ALOFT AND MID-
LEVEL DRYING. STORM MOTION IS TO THE NE AT 25KTS. SO EVEN HEAVY
SHOWERS MAY HAVE LESS POTENTIAL RUNOFF IMPACT DUE TO HAIL
PRODUCTION AND SPEED OF STORMS. STILL THE FOUR CORNERS SOILS ARE
SATURATED OR NEARLY SO.
THE HRRR HAS BEEN PERFORMING WELL IN THE SHORT TERM AND SHOWS A
SIGNIFICANT WAVE LIFTING THROUGH THE FOUR CORNERS THIS LATE
AFTERNOON THEN WEAKENING NORTH OF THE SAN JUANS THIS EVENING TO
ALONG THE I-70 CORRIDOR AROUND MIDNIGHT. LIGHTNING...HEAVY
RAIN...HAIL...AND WIND GUSTS ARE EXPECTED ALONG THIS LINE THIS
AFTERNOON AND EVENING.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 338 AM MDT TUE OCT 20 2015
CONVECTION CONTINUES TO ROLL NORTHEAST ACROSS THE REGION THIS
MORNING WITH BULK OF ACTIVITY ACROSS OUR CENTRAL ZONES. INTENSITY
HAS BACKED DOWN...ALTHOUGH STILL SEEING A FEW STRONGER CELLS
PRODUCING FREQUENT LIGHTNING. SHORTWAVE ROTATING NORTHEAST WILL
CONTINUE TO DRIVE THIS ACTIVITY INTO OUR NORTHERN ZONES...WHERE
CONDITIONS ARE COOLER AND EXPECT THIS ACTIVITY TO DIMINISH OR
SLOWLY DISSIPATE AS IT LIFTS TOWARDS WYOMING. HRRR AND RAP BOTH
IN AGREEMENT WITH THIS SCENARIO AND WILL DECREASE POPS AS WE WORK
NORTHEAST ACROSS THE FORECAST AREA.
AS FOR TODAY...DEEP CLOSED LOW OVER THE SOUTHWEST STATES WILL
CONTINUE TO PUMP MOISTURE NORTH AND EAST ACROSS THE FORECAST AREA.
ANOTHER WAVE ROUND THE BASE OF THE LOW EVIDENT IN WATER VAPOR
IMAGERY THIS MORNING. THIS WILL ROTATE UP AND INTO OUR SOUTHERN
ZONES BY THIS AFTERNOON...SPARKING ANOTHER ROUND OF STRONGER
STORMS...ALTHOUGH NOT QUITE AS STRONG AS WE SAW LAST EVENING.
PRECIPITABLE WATER VALUES STILL QUITE HIGH FOR THIS TIME OF YEAR
AND WILL CONTINUE THE FLASH FLOOD WATCH FOR SOUTHEAST UTAH...WHICH
WILL BE MORE PRONE TO QUICK AND SUDDEN RUNOFF IN OUR SLOT AND ROCK
COUNTRY. WITH THE LOW SLOW TO MOVE...CONVECTION WILL CONTINUE
THROUGH TONIGHT AND INTO THE DAY TOMORROW WITH LOCALLY HEAVY RAIN
STILL POSSIBLE OVER JUST ABOUT ANYWHERE THAT SEES CONVECTION ROLL
THROUGH. TEMPERATURES WILL BE COOL...BUT FORCING ASSOCIATED WITH
EJECTING WAVES WILL KEEP THE CONVECTION GOING.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 338 AM MDT TUE OCT 20 2015
THE LOW IS EXPECTED TO SLOWLY FILL AND LIFT NORTHEAST ACROSS
COLORADO WEDNESDAY NIGHT AND THURSDAY. THIS WILL EVENTUALLY ALLOW
FOR COLDER CONDITIONS TO PUSH IN LATE THURSDAY AND THURSDAY NIGHT.
EXPECT SNOW LEVELS TO DROP A BIT...MAYBE AS LOW AS 9K BY FRIDAY
MORNING. WILL TAKE A CLOSER LOOK AT THAT POTENTIAL LATER TODAY. AT
NOW APPEARS THAT THE WEEKEND WILL BE DRIER...WITH BOTH THE ECMWF
AND GFS BACKING OFF QPF NUMBERS SATURDAY AND SUNDAY. WITH SOME
AGREEMENT THERE...WILL STICK WITH THE BLENDED SOLUTIONS AND ALLOW
POPS TO TAIL OFF THROUGH THE LATER PERIODS. ANOTHER WAVE DOES
APPROACH BY MONDAY...BUT TIMING DIFFERENCES KEEPING CONFIDENCE
LOW WITH THAT SYSTEM. TEMPS WILL BE RUNNING NEAR TO SLIGHT BELOW
SEASONAL NORMS TO START OFF THE EXTENDED...WITH A NUDGE UP OVER
THE WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1215 PM MDT TUE OCT 20 2015
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS EASTERN
UTAH AND WESTERN COLORADO THROUGH WEDNESDAY. STRONG STORMS ARE
POSSIBLE THIS AFTERNOON AND EVENING FOR AREA UP TO THE I-70
CORRIDOR. A FEW STORMS WILL BE STRONG AND CAPABLE OF PRODUCING
HAIL UP TO 1 INCH IN DIAMETER AND GUSTY OUTFLOW WINDS IN EXCESS OF
45 KTS. CIGS WILL BRIEFLY DROP BELOW MVFR THRESHOLDS AS SHOWERS
MOVE THROUGH. SNOW LEVELS LOOK TO REMAIN AOA 10K THROUGH THIS
OPERATIONAL PERIOD. IFR OR LIFR CONDITIONS ARE MOST LIKELY FOR
KDRO KTEX FROM 21Z-00Z...KMTJ KCNY KMTJ KASE KEGE FROM 00Z-06Z.
MOUNTAIN TOPS WILL BE OBSCURED AT TIMES THROUGH THE PERIOD.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...FLASH FLOOD WATCH UNTIL 9 PM MDT THIS EVENING FOR UTZ022-027>029.
&&
$$
UPDATE...JOE
SHORT TERM...JDC
LONG TERM...JDC
AVIATION...JOE
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
650 PM EDT TUE OCT 20 2015
.SYNOPSIS...
HIGH PRESSURE WILL PREVAIL THROUGH FRIDAY WHILE A WEAK TROUGH OF LOW
PRESSURE LINGERS OFFSHORE. A WEAK COLD FRONT WILL MOVE THROUGH
FRIDAY NIGHT...FOLLOWED BY HIGH PRESSURE THROUGH THE WEEKEND. A COLD
FRONT COULD AFFECT THE AREA EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
LARGE HIGH PRESSURE...1027 HPA...CENTERED ALONG THE NORTH
CAROLINA OUTER BANKS WILL HOLD ITS INFLUENCE ON THE AREA TONIGHT.
A BROAD EAST/NORTHEAST FLOW WILL CONTINUE TO ADVECT OCCASIONAL
BOUTS OF STRATOCUMULUS ONSHORE THROUGH THE NIGHT...MAINLY OVER
COASTAL GEORGIA...BUT IT REMAINS TO BE SEEN EXACTLY HOW WIDESPREAD
THIS CLOUD COVER WILL BECOME. THE LATEST NAM AND RAP SHOW A BIT
LESS CLOUD COVER THAN PREVIOUS RUNS...BUT ARE STILL MORE
AGGRESSIVE THAN THE 20/12Z GEM CLOUD COVER PRODUCT. HAVE LOWERED
CLOUD COVER JUST A BIT GIVEN THE LATEST SHORT TERM MODEL
TRENDS...BUT STILL SHOW SKIES BECOMING MOSTLY CLOUDY ROUGHLY
ALONG/SOUTH OF A HILTON HEAD-LUDOWICI LINE EARLY WEDNESDAY
MORNING AS WEAK ISENTROPIC ASSENT ENSUES. EXPECT MAINLY CLEAR
SKIES TO PREVAIL INLAND.
WEAK ISENTROPIC 295-300K ASSENT LOOKS TO DEVELOP ALONG THE
GEORGIA COAST AFTER 2-3 AM...WHICH COULD SUPPORT A FEW SHOWERS
MOVING INLAND FROM OFF THE ATLANTIC. DO NOT ANTICIPATE MUCH INLAND
PENETRATION OF ANY SHOWER ACTIVITY THAT DOES APPROACH THE GEORGIA
BEACHES...SO SLIGHT CHANCE POPS WILL BE CONFINED IN THOSE ZONES
WITH DRY CONDITIONS ELSEWHERE.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
AN UPPER LEVEL RIDGE WILL EXPAND FROM THE GULF OF MEXICO WEDNESDAY
THROUGH FRIDAY. AS THIS OCCURS...SURFACE HIGH PRESSURE IN THE
WESTERN ATLANTIC WILL SHIFT FARTHER OFFSHORE...WITH A SURFACE RIDGE
AXIS EXTENDING BACK ACROSS NORTH CAROLINA. MEANWHILE...EXPECT A VERY
WEAK COASTAL TROUGH TO LINGER JUST OFF THE SOUTHEAST COAST.
AN ONSHORE COMPONENT TO THE LOW-LEVEL FLOW SHOULD ADVECT AMPLE
MOISTURE IN TO PRODUCE A FAIR AMOUNT OF CUMULUS AND/OR
STRATOCUMULUS...ESPECIALLY WEDNESDAY AND THURSDAY...WITH SKIES
PARTLY TO MOSTLY CLOUDY AT TIMES. MODELS SHIFTED THE ENHANCED LOW
LEVEL CONVERGENCE CLOSER TO THE COAST BOTH OF THESE DAYS, SO
ADJUSTED POPS UPWARDS ALONG THE IMMEDIATE COAST TO REFLECT THIS.
EXPECT ISOLATED SHOWERS ACROSS THE COASTAL AREAS, BUT NOT A COMPLETE
WASHOUT. FRIDAY THE COASTAL TROUGH SHIFTS FURTHER OFFSHORE AS
SURFACE HIGH MOVES CLOSER TO THE COAST. THIS INCREASED SUBSIDENCE
WILL LEAD TO A DRY FRIDAY.
TEMPERATURES WILL BE ON A WARMING TREND THROUGH THE END OF THE WEEK
GIVEN THE RISING HEIGHTS ALOFT. HIGHS ON WEDNESDAY SHOULD BE NEAR
NORMAL (IN THE MID TO UPPER 70S), THEN ABOVE NORMAL THURSDAY AND
FRIDAY WITH MOST AREAS AWAY FROM THE COAST AROUND 80 OR IN THE LOWER
80S.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
A SHORT WAVE TROUGH SWINGING ACROSS NEW ENGLAND SHOULD DRIVE A
WEAK/DRY COLD FRONT THROUGH THE AREA FRIDAY NIGHT...BUT UPPER LEVEL
RIDGING OVER THE GULF OF MEXICO WILL GENERALLY PREVAIL THROUGH THE
WEEKEND AS HIGH PRESSURE REBUILDS FROM THE NORTH/NORTHEAST. EXPECT
RAIN-FREE CONDITIONS THROUGH THE WEEKEND GIVEN SUBSIDENCE...LIMITED
MOISTURE AND A LACK OF SIGNIFICANT FORCING. TEMPERATURES WILL
GENERALLY BE NEAR NORMAL.
ALTHOUGH MODELS DIFFER WITH SOME OF THE SYNOPTIC DETAILS...
CONDITIONS APPEAR TO BECOME A BIT MORE UNSETTLED EARLY NEXT WEEK AS
A FRONT APPROACHES FROM THEN NORTHWEST AND DEEP MOISTURE ADVECTS
INTO THE REGION.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
VFR. COULD SEE A BRIEF BOUT OF MVFR CIGS AT KSAV AT TIMES
OVERNIGHT AS STRATOCUMULUS MOVES INLAND...BUT SUSPECT ANY CIGS
THAT ARE ESTABLISHED WILL REMAIN JUST ABOVE MVFR THRESHOLDS.
EXTENDED AVIATION OUTLOOK...MVFR IS POSSIBLE THROUGH THURSDAY...
ESPECIALLY AT KSAV...DUE TO INCREASED LOW LEVEL MOISTURE AND A
COASTAL TROUGH LINGERING JUST OFFSHORE. OTHERWISE...VFR WILL
PREVAIL.
&&
.MARINE...
TONIGHT...A MODEST PRESSURE GRADIENT WILL HOLD IN PLACE TONIGHT AS
HIGH PRESSURE REMAIN ANCHORED TO THE NORTH/NORTHEAST. NORTHEAST
WINDS OF 15-20 KT WILL PREVAIL FOR MUCH OF THE NIGHT WITH SEAS 2-4
FT NEARSHORE WATERS AND 4-6 FT OFFSHORE WATERS. TRENDS AT BUOYS
41008 AND 41112 SUGGEST SEAS HAVE DROPPED BELOW 6 FT ACROSS THE
GEORGIA NEARSHORE WATERS...SO THE SMALL CRAFT ADVISORY HAS BEEN
CANCELLED THERE. IT REMAINS IN EFFECT UNTIL LATE THIS EVENING FOR
THE GEORGIA OFFSHORE WATERS AND CURRENT TRENDS SUGGEST THIS TIMING
LOOKS GOOD.
WEDNESDAY THROUGH SUNDAY...HIGH PRESSURE WILL PREVAIL OVER THE
WESTERN CAROLINAS THROUGH THURSDAY. A SEPARATE AREA OF HIGH PRESSURE
WILL ALSO PREVAIL FAR OFF THE COAST OF THE NORTHEASTERN U.S. DURING
THIS SAME TIME PERIOD. THE INTERACTION BETWEEN THESE TWO HIGHS AND
AN ELONGATED BUT WEAK COASTAL TROUGH JUST OFFSHORE WILL CREATE A
SURFACE PRESSURE GRADIENT WHICH SHOULD SUPPORT A NORTHEAST MODERATE
BREEZE (AROUND 15 KT). WINDS FURTHER OFFSHORE SHOULD REACH THE
STRENGTH OF A FRESH BREEZE (AROUND 20 KT). THESE STRONGER WINDS IN
CONJUNCTION WITH A LONG FETCH POINTED TOWARDS THE SOUTHEAST COAST
WILL ALLOW LARGER WAVES TO BUILD. THESE WAVES WILL PROPAGATE INTO
OUR WATERS, MAINTAINING ELEVATED SEAS THROUGH AT LEAST THURSDAY OR
POSSIBLY FRIDAY. SEAS ACROSS THE OUTER GEORGIA WATERS COULD BUILD
TO 6 FT LATE WEDNESDAY THROUGH FRIDAY, WHICH WOULD NECESSITATE A
SMALL CRAFT ADVISORY. HELD OFF ON ISSUING ONE WITH THIS PACKAGE
BECAUSE THERE IS STILL SOME VARIABILITY POSSIBLE IN THE WAVE
HEIGHTS, GIVEN THE STRENGTH OF THE WINDS OFFSHORE AND THE
ORIENTATION THE BEST FETCH TOWARDS THE COAST. A WEAK COLD FRONT
WILL PASS TO OUR NORTH THURSDAY NIGHT INTO FRIDAY
MORNING...WEAKENING THE SURFACE PRESSURE GRADIENT AND ALLOWING
BOTH WINDS AND SEAS TO TREND DOWNWARD. HIGH PRESSURE BUILDING IN
EARLY THIS WEEKEND WILL RESULT IN BRIEFLY IMPROVING CONDITIONS
BEFORE THEY COULD START DETERIORATING AGAIN EARLY NEXT WEEK.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR AMZ374.
&&
$$
ST
AREA FORECAST DISCUSSION
NWS LINCOLN IL
301 PM CDT TUE OCT 20 2015
.SHORT TERM...(Tonight)
ISSUED AT 300 PM CDT TUE OCT 20 2015
19z/2pm surface analysis shows a 1030mb high centered over the
southeast CONUS and a cold front extending from the Great Lakes into
the Northern Plains. Between these two features...strong
southwesterly winds will continue to transport warm air into
Illinois tonight. Latest satellite/radar composite shows remnants
of convective cluster that formed along the nose of a low-level jet
late last night over northwest Missouri now crossing the Mississippi
River just north of Quincy. These showers will continue to track
northeastward over the next few hours, mainly impacting locations
northwest of the Illinois River. As the nocturnal LLJ once again
strengthens from eastern Kansas to northern Illinois tonight,
additional showers will develop across north-central Illinois. Both
the NAM and HRRR suggest the northern half of the KILX CWA could
potentially see showers, so will carry a slight chance PoP across
this area accordingly. Further south will maintain a dry forecast.
Due to increasing cloud cover and a continued southerly wind of 10-
15 mph, overnight low temperatures will be considerably warmer than
in recent nights. Readings will range from the upper 40s near the
Indiana border, to the middle to upper 50s along/west of I-55.
&&
.LONG TERM...(Wednesday through Tuesday)
ISSUED AT 300 PM CDT TUE OCT 20 2015
Breezy southwest winds will continue Wednesday as high
pressure remains off the central Atlantic coastline and low
pressure moves eastward through the northern Great Lakes area.
Sustained SW winds around 15 mph with gusts 20-25 mph can be
expected. A frontal boundary trailing the low will bring at least a
slight chance for showers and isolated thunderstorms settling
southward through central IL Wednesday evening through Thursday as
moisture advects northward from the Gulf in southerly flow ahead of
the boundary. Warm conditions will precede the front...with highs
reaching around 80 degrees throughout central IL
Wednesday...lowering several degrees from I-72 northward for
Thursday. To the south...little cooling will take place as the front
stalls out and weakens in that vicinity. Highs mainly in the low to
mid 70s will follow for Friday and Saturday.
Next chance for precipitation will take place Friday into Saturday
as models coming into fairly good agreement tracking a surface low
into the upper Midwest by Friday evening...with precipitation moving
into western Illinois by Friday afternoon. General model trend has
been to move this system in faster over the past few days...with the
latest runs continuing to speed up the system...although the run-to-
run differences are not dramatic as of the 12Z run. Timing of
the cold front associated with this system...combined with forecast
instability ahead of the front still supports a chance for
thunderstorms Saturday...especially toward the southern and eastern
portions of Illinois.
Cooler and dry conditions will follow the front for Sunday through
Tuesday...except for possibly a few showers lingering in SE Illinois
Sunday. Highs should drop back to near normal for central/SE
Illinois...with highs in the upper 50s to mid 60s and lows
generally in the low 40s.
&&
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 1226 PM CDT TUE OCT 20 2015
Brisk southwesterly winds gusting to between 20 and 25kt will
persist for the balance of the afternoon before subsiding to
around 12kt by sunset. Models show another nocturnal LLJ
developing tonight, oriented from eastern Kansas to northern
Illinois. While the core of the jet will remain just W/NW of the
central Illinois terminals, forecast soundings suggest 40kt
winds developing at around 1500ft at KPIA overnight. Mid/high
clouds will be on the increase tonight as well, as the jet
strengthens and a weak short-wave tracks through the region. Many
high-res models show scattered showers/thunder developing along
the nose of the jet across Iowa, then pushing into northern
Illinois overnight. Due to the proximity of these showers, have
included VCSH at KPIA between 05z and 11z. After that, short-wave
quickly passes to the east and the mid-level clouds scatter by
Wednesday morning.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Barnes
LONG TERM...Onton
AVIATION...Barnes
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1226 PM CDT TUE OCT 20 2015
.UPDATE...
ISSUED AT 1046 AM CDT TUE OCT 20 2015
Another breezy and unseasonably warm day is unfolding across
central Illinois...courtesy of high pressure anchored over the
southeast CONUS. The only potential fly-in-the-ointment is a small
cluster of convection that has developed ahead of a cold front
over northwest Missouri. These storms have been tracking to the E/NE
this morning and will continue to do so over the next few hours.
Most model guidance suggests the convection will remain W/NW of the
KILX CWA: however, the HRRR shows it potentially tracking across
locations northwest of the Illinois River by mid to late afternoon.
Based on current radar/satellite loops...will trend toward the HRRR
solution. As a result...will be maintaining slight chance PoPs for
showers across the NW CWA this afternoon. Elsewhere around the
area...am expecting partly to mostly sunny skies with high
temperatures climbing well into the 70s.
&&
.SHORT TERM...(Today)
ISSUED AT 329 AM CDT TUE OCT 20 2015
Gusty southwest winds will highlight the weather today. The winds
will be driven by a relatively tight pressure gradient across IL
from NW to SE, as our area remains wedged between high pressure in
the southeast states and a cold front extending from Lake Superior
to western Kansas. The cold front will sag closer to IL this
afternoon, with spotty showers or sprinkles possible after 21z/4 pm
for areas NW of the Illinois river. Moisture content of the
approaching airmass will be limited, so any rainfall amounts will be
very light. Despite increasing cloud cover this afternoon, high
temps will climb above yesterday, with readings in the mid 70s
toward Indiana and upper 70s in west of I-55.
.LONG TERM...(Tonight through Monday)
ISSUED AT 329 AM CDT TUE OCT 20 2015
High pressure has settled over the southern Atlantic Coast this
morning as south/southwesterly flow continues into the Midwest. The
warmer temperatures will continue through tomorrow. The overnight
forecast is mainly dry with the exception of areas along and NW of
the Illinois River Valley. A weak boundary to the NW will settle
into the Midwest providing a focus for some sct precip. The airmass
that the boundary is running into is fairly dry and precip will be
difficult to come by, but the models are persistent in developing a
few showers. Warm temps through Wednesday and dry...but a weak
boundary settling/developing in the region will allow for a more
northeasterly flow to winds through the end of Thursday and limit
the afternoon warming. Models previously kept the sct showers to the
north, however, recent runs are dropping the sfc wind convergence a
little further south. As of yet, leaving Thursday dry. The 00z GFS
came in with a thin line of showers associated with this front and
cannot rule out the possible addition of some low pops for Thursday,
but will hinge greatly on how much moisture can actually return to
the atmosphere over the next few days with the continued southerly
flow off of the Gulf Coast, and more southwesterly aloft from the
deeper moisture to the SW. Previously drier forecast is starting to
erode well before the weekend system, but a lot hinges on the
moisture advection from the SW, so the pops will remain low.
The upper low over the SW finally kicks out and through the Midwest
bringing the best precip chances in the forecast for this
weekend...Friday night and Saturday. Have kept the mention of
thunder in the southern half of the CWA for Saturday as the front
settles into the area with the max heat of the afternoon. Temps a
little more seasonal going into the work week with highs in the
lower 60s and lows in the low to mid 40s.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 1226 PM CDT TUE OCT 20 2015
Brisk southwesterly winds gusting to between 20 and 25kt will
persist for the balance of the afternoon before subsiding to
around 12kt by sunset. Models show another nocturnal LLJ
developing tonight, oriented from eastern Kansas to northern
Illinois. While the core of the jet will remain just W/NW of the
central Illinois terminals, forecast soundings suggest 40kt
winds developing at around 1500ft at KPIA overnight. Mid/high
clouds will be on the increase tonight as well, as the jet
strengthens and a weak short-wave tracks through the region. Many
high-res models show scattered showers/thunder developing along
the nose of the jet across Iowa, then pushing into northern
Illinois overnight. Due to the proximity of these showers, have
included VCSH at KPIA between 05z and 11z. After that, short-wave
quickly passes to the east and the mid-level clouds scatter by
Wednesday morning.
&&
.FIRE WEATHER...
ISSUED AT 329 AM CDT TUE OCT 20 2015
Fire weather risk will remain a concern today, due to SW winds
gusting up to 20-25 mph, low relative humidity of 25-30% and dry
fuel moisture. Increasing cloud cover ahead of the approaching cold
front will reduce mixing heights this afternoon, keeping winds lower
than yesterday. Increasing dewpoints will keep relative humidity
slightly higher as well, which prevent us from reaching Red Flag
Warning criteria today. However, burning will still be discouraged
due to the borderline conditions.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Barnes
SHORT TERM...Shimon
LONG TERM...HJS
AVIATION...Barnes
FIRE WEATHER...Shimon
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
1218 PM CDT TUE OCT 20 2015
...UPDATED AVIATION SECTION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 245 AM CDT TUE OCT 20 2015
NAM, GFS, and RAP were all in good agreement with another upper
level disturbance, located just west of Baja California at 00z
Tuesday, approaching southwest Kansas early tonight. A surface
trough of low pressure will be located from southeast Colorado
into south central Nebraska by late day. Latest NAM indicating
limited low level forcing along this front and 0-6km shear will be
20 knots or less. CAPE values near the surface trough is forecast
to be less than 600 J/Kg so at this time not overly excited about
late day convection, however unable to rule out a few isolated
storms in far western Kansas early this evening. The chance for
will improve during the overnight hours as moisture and improving
upper level lift develops ahead of an upper level trough that is
forecast to cross western Kansas tonight. At this time the better
forcing will be across far western Kansas early tonight and then
shift north after midnight.
The potential for afternoon cloud cover will make temperatures a
little tricky today, however am expecting a fair amount of sun so
will based highs on 00z Wednesday 850mb temperatures. This is
close to the latest guidance of highs mainly in mid 80s.
.LONG TERM...(Wednesday THROUGH Monday)
ISSUED AT 245 AM CDT TUE OCT 20 2015
On Wednesday moisture will continue to improve in the 850mb to
700mb level as another upper level disturbance approaches from the
southwest. Better difluent flow will be present aloft, especially
late day as a surface boundary drops south into southwest Kansas.
Given this will stay close to the previous forecast with
precipitation chances increasing late day and early Wednesday
night.
The best chance for widespread precipitation still appears to
occur across western and central Kansas late Wednesday night and
Thursday given the moisture forecast across western Kansas and the
location of the upper level jet streak east of the upper low that
will be crossing the four corners region on Thursday. Also given
the expected precipitation and cloud cover will continue to favor
lows near or above guidance while undercutting highs on Thursday.
Thursday night into Friday the upper low opens up as it lifts
northeast into the northern Plains. As this upper level trough
crosses western Kansas Thursday night the precipitation chances is
expected to taper off from west to east. There will then be a
slight chance for some showers or even an isolated thunderstorm
late Friday night as a weak upper level trough crosses the central
high plains.
The weekend will be mainly dry and cool with highs mainly in the
60s Both Saturday and Sunday.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z Wednesday AFTERNOON)
ISSUED AT 1212 PM CDT TUE OCT 20 2015
VFR expected at KDDC, KGCK and KHYS through the TAF period. A
surface trough extending from near KHYS southwestward to near KGCK
is resulting in breezy southwest surface winds across the region.
A shortwave trough lifting out of the Four Corners region will
bring increasing high clouds tonight and widely scattered
showers/isolated thunderstorms overnight and into Wednesday
morning with a low risk of directly impacting the terminals with
flight restrictions.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 84 56 73 56 / 0 20 40 80
GCK 85 55 67 53 / 0 30 60 80
EHA 82 55 66 53 / 20 30 70 80
LBL 84 57 73 56 / 20 20 50 80
HYS 85 56 70 54 / 0 30 40 60
P28 83 60 77 59 / 20 10 30 70
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Burgert
LONG TERM...Burgert
AVIATION...GLD/024
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
327 PM EDT TUE OCT 20 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 305 PM EDT TUE OCT 20 2015
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOWS SHORTWAVE ENERGY
APPROACHING FROM THE ROCKIES AND NORTHERN PLAINS. BRISK N TO NE
WINDS ACROSS THE AREA AHEAD OF SFC HIGH PRES BUILDING INTO NRN
ONTARIO HAVE SUPPORTED A PERSISTENT PATCH OF UPSLOPE STRATOCU OVER
BARAGA COUNTY AND THE NW HALF OF MQT COUNTY. WITH THE WARM FRONTAL
BOUNDARY FROM SYSTEM OVER THE PLAINS SAGGING SOUTH OF MNM COUNTY AND
NRN LAKE MI...RAIN SHOWERS HAVE DISSIPATED THIS AFTERNOON OVER
SCNTRL FCST AREA.
TONIGHT...AS SHORTWAVE ENERGY MOVES ACROSS THE NRN PLAINS/SCNTRL
CANADA TONIGHT...850MB WAA DEVELOPS ACROSS THE AREA.
HOWEVER...CONSENSUS OF MODELS INDICATES BETTER ISENTROPIC MOIST
ASCENT WL STAY SE OF THE FCST AREA. MEANWHILE...BEST DEEP LAYER
FORCING ASSOCIATED WITH APPROACHING SHORTWAVE ENERGY WILL BE NW OF
THE FCST AREA AS NOTED ON 700-300 MB Q-VECTOR CONVERGENCE. THIS
STILL ARGUES FOR TWO AREAS OF DEVELOPING PCPN TO SPLIT SE AND NW OF
THE FCST AREA TONIGHT...WHICH IS STILL CONSISTENT WITH MODEL QPF
GUIDANCE. THUS WILL CONTINUE TO ONLY CARRY SCHC POPS TONIGHT.
WEDNESDAY...A STRONG SHORTWAVE AND DEVELOPING CLOSED LOW WILL BE
MOVING FROM SOUTHERN MANITOBA THROUGH NORTHERN ONTARIO WITH 150M 12
HR 5H HEIGHT FALLS FCST BY MODELS OVER NORTHERN ONTARIO. MODEL
CONSENSUS SHOWS A DEEPENING SFC LOW MOVING ACROSS THE TIP OF THE
KEWEENAW IN THE AFTERNOON AND THEN LIFTING NE OF LAKE SUPERIOR BY
WED EVENING. THE BEST DEEP LAYER FORCING ASSOC WITH THE SHORTWAVE
WILL BE NORTH OF THE LAKE SUPERIOR ALONG THE SHORTWAVE TRACK AND
AGAIN THE BETTER MOIST ISENTROPIC ASCENT WILL REMAIN SE OF THE FCST
AREA. THIS SPLIT IN FORCING WILL WORK TO KEEP RAIN SHOWERS ISOLATED
TO SCATTERED AT BEST AS THE FRONTAL SYSTEM MOVES ACROSS THE AREA
WITH THE BETTER COVERAGE OVER THE EAST HALF OF THE CWA WHERE
ISENTROPIC ASCENT WILL BE MAXIMIZED. ADDITIONALLY...BEHIND THE
SURFACE COLD FRONT...MODELS ADVERTISE A RISE/FALL COUPLET WHICH WILL
AID GUSTY W TO NW WINDS BEHIND THE FRONT LATE IN THE AFTERNOON INTO
EARLY EVENING AS COLD ADVECTION INCREASES DESTABILIZATION AND
MIXING. THIS COULD ALL LEAD TO GUSTS UP TO 35 TO 40 MPH OVER THE
KEWEENAW PENINSULA AND NEAR LAKE SUPERIOR OVER NW MARQUETTE COUNTY
IN THE LATE AFTERNOON AND EVENING HOURS...WITH A BRIEF PERIOD OF
GALES POSSIBLE OVER LAKE SUPERIOR LATE AFTERNOON INTO EVENING HOURS.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 327 PM EDT TUE OCT 20 2015
EXITING LOW WEDNESDAY NIGHT...ANOTHER LOW NEARING FROM THE W FRIDAY
AFTERNOON/EVENING AND CROSSING THE CWA THIS WEEKEND WILL RESULT IN A
COUPLE OF INCREASED WIND EVENTS FOR WEDNESDAY NIGHT...AND THEN LATE
FRIDAY AFTERNOON THROUGH SATURDAY.
STEADY SYNOPTIC PRECIP WILL QUICKLY EXIT E UPPER MI WEDNESDAY
EVENING. PW VALUES AROUND 0.5IN OR LESS AT 00Z THURSDAY OVER THE W
HALF...WITH 1IN VALUES EXITING FAR E. NW FLOW WILL QUICKLY SLIDE IN
WEDNESDAY EVENING AS THE SFC LOW OVER FAR NE LAKE SUPERIOR AT 00Z
AND THE DRAGGING COLD FRONT EXITS JUST E OF THE CWA...WITH RAPIDLY
INCREASING WINDS DURING THE EVENING HOURS...PARTICULARLY ACROSS THE
KEWEENAW PENINSULA AND E WITH WINDS GUSTING 25-35KTS. BY DAYBREAK
THURSDAY THE SFC LOW WILL BE JUST S OF JAMES BAY AND THE COLD FRONT
WILL BE E OF LAKE HURON. HOWEVER...A SECONDARY TROUGH WRAPPING
AROUND THE LOW WILL BE SET UP ACROSS S LAKE SUPERIOR AT 12Z
THURSDAY...PROLONGING THE WNW WINDS A BIT LONGER. 850MB TEMPS OF
-1 TO -3C THURSDAY MORNING WITH THESE UPSLOPE/LAKESHORE CONVERGENT
WINDS WILL KEEP LAKE ENHANCED CLOUDS AND SHOWERS LINGERING THROUGH
THE MORNING HOURS.
HIGH PRESSURE SET UP FROM HUDSON BAY THROUGH IA AT 12Z THURSDAY WILL
SHIFT TO CENTRAL ONTARIO AND LAKE SUPERIOR BY THE END OF THE DAY
WITH LIGHTER WINDS TAKING HOLD OVER THE W HALF OF THE CWA BY MID
AFTERNOON.
THE AREA OF HIGH PRESSURE/RIDGE WILL THEN MOVE OVER THE E HALF OF
THE CWA BY 06Z FRIDAY...THEN EXIT E AS THE 500MB RIDGE SLIDES
OVERHEAD. THE PRESSURE GRADIENT WILL QUICKLY INCREASE BEHIND THE
HIGH AS A DEEPENING LOW NEARS FROM THE NORTHERN PLAINS FRIDAY
AFTERNOON. LOOK FOR THE LOW TO SLIDE ACROSS MN FRIDAY NIGHT AND
ACROSS OR JUST N OF LAKE SUPERIOR BY 18Z SATURDAY. A WIDESPREAD 0.1
TO 0.3IN OF RAIN LOOKS LIKELY...STILL WITH THE BULK OF PRECIP
FALLING ACROSS LAKE SUPERIOR EARLY SATURDAY MORNING. EXPECT PLENTY
OF CLOUDS OF MOISTURE TO LINGER BEHIND THE LOW...AS THE 500MB TROUGH
SET UP ACROSS MN AT 12Z SATURDAY MOVES ACROSS LAKE SUPERIOR/UPPER MI
MAINLY DURING THE AFTERNOON HOURS. ZONAL FLOW LOOKS TO TAKE OVER
BEHIND THE TROUGH FOR SUNDAY AND INTO EARLY MONDAY...WITH AN
EMBEDDED SHORTWAVE MONDAY AFTERNOON AND YET ANOTHER TROUGH POSSIBLY
SHIFTING IN FROM THE NW LATE MONDAY NIGHT INTO TUESDAY. WILL KEEP
THE POTENTIAL OF LIGHT MIXED PRECIP GOING SUNDAY NIGHT INTO EARLY
MONDAY AND AGAIN MONDAY NIGHT INTO EARLY TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 119 PM EDT TUE OCT 20 2015
OTHER THAN SOME LINGERING STRATUS WHICH COULD BRING AN HOUR OF MVFR
CIGS TO KSAW FROM 18-19Z...EXPECT VFR CONDITIONS AT KIWD/KCMX/KSAW
THRU AT LEAST THE EVENING HOURS AS LOW LEVELS REMAIN DRY. MOISTURE
WILL BEGIN TO INCREASE LATE TONIGHT AS A LOW PRES TROF APPROACHES.
WITH AN UPSLOPE WIND COMPONENT...KCMX/KSAW WILL LIKELY SEE CIGS FALL
TO MVFR LATE TONIGHT INTO WED MORNING WITH THE LOWER CIGS (POSSIBLY
TO LIFR) AT KSAW DUE TO UPSLOPE FLOW ORIGINATING OFF THE WARMER
WATERS OF LAKE MICHIGAN. MVFR CIGS SHOULD SNEAK INTO KIWD LATE IN
THE TAF PERIOD (16-18Z) AS WINDS SHIFT TO A MORE UPSLOPE WSW
DIRECTION.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 305 PM EDT TUE OCT 20 2015
HIGH PRES ACROSS NRN ONTARIO WILL MAINTAIN BRISK NE WINDS IN THE 15-
30KT RANGE ACROSS LAKE SUPERIOR INTO THIS EVENING...STRONGEST OVER
THE WESTERN THIRD OF THE LAKE WHERE THE TERRAIN WILL FUNNEL AND
ENHANCE THE FLOW. WINDS WILL THEN VEER TO THE E-SE TONIGHT/WED
MORNING AS HIGH PRES MOVES TO QUEBEC AND A LOW PRES TROF APPROACHES.
THE STRONGER SE WINDS UP TO 30KT ARE MOST LIKELY OVER THE E HALF OF
THE LAKE ON WED. A LOW PRES CENTER WILL DEVELOP ALONG THE TROF AND
PASS JUST N OF LAKE SUPERIOR WED AFTN. AS THIS OCCURS...A FAVORABLY
ALIGNED PRES RISE/FALL COUPLET WILL GIVE AN ISALLOBARIC BOOST TO THE
WESTERLY WINDS IN THE WAKE OF COLD FROPA. THIS SHOULD RESULT IN A
BRIEF PERIOD OF WESTERLY GALES TO 35 KNOTS ALONG THE TIP AND IN THE
LEE OF THE KEWEENAW LATE WED AFTERNOON/EVENING SO WL INCLUDE A GALE
WARNING FOR LSZ264>266 FOR THIS PERIOD. WINDS WILL SHIFT NW WED
NIGHT THEN DIMINISH THU AS HIGH PRES BUILDS INTO THE UPPER GREAT
LAKES. WINDS WILL THEN BE ON THE INCREASE FRI/SAT AS ANOTHER LOW
PRES TROF SWEEPS THRU THE UPPER GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 7 PM WEDNESDAY TO 2 AM EDT THURSDAY FOR
LSZ264>266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...KF
AVIATION...VOSS
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
305 PM EDT TUE OCT 20 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 305 PM EDT TUE OCT 20 2015
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOWS SHORTWAVE ENERGY
APPROACHING FROM THE ROCKIES AND NORTHERN PLAINS. BRISK N TO NE
WINDS ACROSS THE AREA AHEAD OF SFC HIGH PRES BUILDING INTO NRN
ONTARIO HAVE SUPPORTED A PERSISTENT PATCH OF UPSLOPE STRATOCU OVER
BARAGA COUNTY AND THE NW HALF OF MQT COUNTY. WITH THE WARM FRONTAL
BOUNDARY FROM SYSTEM OVER THE PLAINS SAGGING SOUTH OF MNM COUNTY AND
NRN LAKE MI...RAIN SHOWERS HAVE DISSIPATED THIS AFTERNOON OVER
SCNTRL FCST AREA.
TONIGHT...AS SHORTWAVE ENERGY MOVES ACROSS THE NRN PLAINS/SCNTRL
CANADA TONIGHT...850MB WAA DEVELOPS ACROSS THE AREA.
HOWEVER...CONSENSUS OF MODELS INDICATES BETTER ISENTROPIC MOIST
ASCENT WL STAY SE OF THE FCST AREA. MEANWHILE...BEST DEEP LAYER
FORCING ASSOCIATED WITH APPROACHING SHORTWAVE ENERGY WILL BE NW OF
THE FCST AREA AS NOTED ON 700-300 MB Q-VECTOR CONVERGENCE. THIS
STILL ARGUES FOR TWO AREAS OF DEVELOPING PCPN TO SPLIT SE AND NW OF
THE FCST AREA TONIGHT...WHICH IS STILL CONSISTENT WITH MODEL QPF
GUIDANCE. THUS WILL CONTINUE TO ONLY CARRY SCHC POPS TONIGHT.
WEDNESDAY...A STRONG SHORTWAVE AND DEVELOPING CLOSED LOW WILL BE
MOVING FROM SOUTHERN MANITOBA THROUGH NORTHERN ONTARIO WITH 150M 12
HR 5H HEIGHT FALLS FCST BY MODELS OVER NORTHERN ONTARIO. MODEL
CONSENSUS SHOWS A DEEPENING SFC LOW MOVING ACROSS THE TIP OF THE
KEWEENAW IN THE AFTERNOON AND THEN LIFTING NE OF LAKE SUPERIOR BY
WED EVENING. THE BEST DEEP LAYER FORCING ASSOC WITH THE SHORTWAVE
WILL BE NORTH OF THE LAKE SUPERIOR ALONG THE SHORTWAVE TRACK AND
AGAIN THE BETTER MOIST ISENTROPIC ASCENT WILL REMAIN SE OF THE FCST
AREA. THIS SPLIT IN FORCING WILL WORK TO KEEP RAIN SHOWERS ISOLATED
TO SCATTERED AT BEST AS THE FRONTAL SYSTEM MOVES ACROSS THE AREA
WITH THE BETTER COVERAGE OVER THE EAST HALF OF THE CWA WHERE
ISENTROPIC ASCENT WILL BE MAXIMIZED. ADDITIONALLY...BEHIND THE
SURFACE COLD FRONT...MODELS ADVERTISE A RISE/FALL COUPLET WHICH WILL
AID GUSTY W TO NW WINDS BEHIND THE FRONT LATE IN THE AFTERNOON INTO
EARLY EVENING AS COLD ADVECTION INCREASES DESTABILIZATION AND
MIXING. THIS COULD ALL LEAD TO GUSTS UP TO 35 TO 40 MPH OVER THE
KEWEENAW PENINSULA AND NEAR LAKE SUPERIOR OVER NW MARQUETTE COUNTY
IN THE LATE AFTERNOON AND EVENING HOURS...WITH A BRIEF PERIOD OF
GALES POSSIBLE OVER LAKE SUPERIOR LATE AFTERNOON INTO EVENING HOURS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 445 AM EDT TUE OCT 20 2015
NEAR TO SLIGHTLY ABOVE NORMAL TEMPERATURES THROUGH SATURDAY...THEN
COOLER AIR RETURNS. A PERIOD OF GUSTY WINDS CAN BE EXPECTED
WEDNESDAY AFTERNOON AND EVENING OVER THE KEWEENAW PENINSULA AND
ALONG LAKE SUPERIOR.
WEDNESDAY AND WEDNESDAY NIGHT...A SURFACE LOW AND UPPER LEVEL 500MB
SHORTWAVE STRETCHING FROM MANITOBA...SOUTHWARD INTO MN WILL BEGIN TO
SHIFT EASTWARD TOWARD UPPER PENINSULA. AS THE LOW CENTER SLIDES
ACROSS LAKE SUPERIOR THROUGH THE DAY AND THE ASSOCIATED COLD FRONT
SLIDES THROUGH THE AREA...EXPECT WIDESPREAD RAIN SHOWERS TO DEVELOP.
THE BEST FORCING WILL REMAIN CLOSER TO THE LOW
CENTER...HOWEVER...THERE WILL BE ENOUGH FORCING ACROSS THE REST OF
THE AREA...AS SHOWN BY ANALYZING 1000-500MB RH ALONG WITH DEEP LAYER
QCONV...TO CREATE WIDESPREAD RAIN SHOWERS. THIS LOW WILL QUICKLY
DEPART TO THE EAST OF THE AREA WEDNESDAY EVENING AS IT RAPIDLY
INTENSIFIES AND MUCH DRIER DEEP LAYER AIR SURGES IN BEHIND IT ON
WESTERLY TO NORTHWESTERLY WINDS. THIS WILL ALLOW FOR A VERY QUICK
END TO THE RAIN SHOWERS FROM WEST TO EAST THROUGH THE EVENING HOURS.
ADDITIONALLY...BEHIND THE COLD FRONT...THE PRESSURE GRADIENT WILL
INCREASE BETWEEN THE DEPARTING LOW AND THE HIGH PRESSURE QUICKLY
BUILDING IN BEHIND IT WEDNESDAY NIGHT. THIS WILL ALLOW FOR GUSTY
WEST TO NORTHWESTERLY WINDS. COULD SEE GUSTS UP TO 30 TO 40 MPH OVER
THE KEWEENAW PENINSULA AND NEAR LAKE SUPERIOR IN THE LATE AFTERNOON
AND EVENING HOURS...WITH A BRIEF PERIOD OF GALES POSSIBLE OVER LAKE
SUPERIOR. THIS WILL BE ESPECIALLY TRUE IF STRONGER WINDS MIX DOWN TO
THE SURFACE. WINDS AT 925MB TO 900MB ARE RIGHT AROUND 35 TO 40
KNOTS...AGAIN WITH CAA...IT WILL BE VERY POSSIBLE FOR THESE STRONGER
WINDS TO MIX DOWN...ESPECIALLY OVER THE KEWEENAW PENINSULA AND LAKE
SUPERIOR. THE SHOWERS COULD LINGER A BIT LONGER OVER THE EASTERN
U.P. DUE TO THE PROXIMITY TO THE DEPARTING LOW ALONG WITH CAA INTO
THE AREA. 850MB TEMPERATURES ARE PROGGED TO DROP TO NEAR
-2C LATE WEDNESDAY NIGHT...WITH THE WEST TO NORTHWEST FLOW...WHICH
WILL AT A MINIMUM KEEP THE POTENTIAL FOR LAKE EFFECT CLOUD COVER
OVER THE EAST HALF NEAR LAKE SUPERIOR.
THURSDAY THROUGH FRIDAY...THE GENERAL TREND IS FOR A SURFACE RIDGE
AND ASSOCIATED UPPER LEVEL RIDGE TO QUICKLY BUILD FROM THE NORTHERN
PLAINS AND CANADA INTO THE UPPER GREAT LAKES THURSDAY AND LINGER
THROUGH MOST OF THE DAY FRIDAY. THIS WILL KEEP MAINLY DRY CONDITIONS
IN THE FORECAST. THERE MAY BE SOME LINGERING LOW CLOUDS AS 850MB
TEMPS SLOWLY START TO REBOUND OVER THE EAST AND THE LOW CONTINUES TO
DEPART THROUGH QUEBEC THROUGH THURSDAY AFTERNOON. OTHERWISE...FOR
THE REST OF THE AREA SKIES WILL BE PARTLY CLOUDY THROUGH FRIDAY
MORNING. FRIDAY AFTERNOON...THE NEXT UPPER LEVEL TROUGH AND SURFACE
LOW SLIDING ACROSS SOUTHERN CANADA...ALONG WITH ASSOCIATED COLD
FRONT...WILL APPROACH THE REGION FROM THE WEST. THIS WILL ALLOW FOR
INCREASING CLOUDS FROM THE WEST...HOWEVER...MOST OF THE AREA SHOULD
REMAIN DRY FOR DURING THE DAY FRIDAY.
FRIDAY NIGHT SATURDAY...THE AFOREMENTIONED LOW PRESSURE SYSTEM AND
ASSOCIATED COLD FRONT WILL CONTINUE TO SLIDE EAST ACROSS THE AREA.
MODELS ARE BECOMING MORE SETTLED ON A SOLUTION WITH THE SURFACE LOW
SLIDING FROM NORTHERN MN FRIDAY NIGHT TO NEAR JAMES BAY BY SATURDAY
EVENING. THIS WILL DRAG A COLD FRONT THROUGH THE AREA THROUGH THE
DAY SATURDAY. THERE WILL BE PLENTY OF MOISTURE AND FORCING ALONG THE
FRONT TO ALLOW FOR A RAINY SATURDAY ACROSS MUCH OF THE U.P. ANOTHER
THING TO NOTE...EVEN THOUGH THIS IS STILL SEVERAL DAYS OUT...IS THAT
BOTH THE GFS/EC SHOW THE UPPER LEVEL SHORTWAVE ASSOCIATED WITH THE
TROUGH DIGGING MUCH FARTHER SOUTH THAN THE EARLIER MODEL RUNS. THIS
ACTS TO INTENSIFY THE SURFACE LOW AS THE 500MB SHORTWAVE IS
STAGGERED BACK TO THE WEST OF THE SURFACE LOW. IF THE LOW DOES
INTENSIFY AS PROGGED...WE COULD BE LOOKING AT ANOTHER PERIOD OF
GUSTY WINDS ACROSS THE AREA ON CAA...DUE TO FAIRLY STRONG PRESSURE
GRADIENT ALONG WITH MIXING OF FAIRLY STRONG WINDS DOWN FROM 850MB.
AGAIN THIS IS A WAYS OUT...BUT DEFINITELY SOMETHING TO KEEP IN MIND.
SATURDAY NIGHT THROUGH THE EXTENDED...THE GFS/EC BOTH AGREE ON A
DECENT RIDGE BUILDING OVER THE WESTERN CONUS WITH BROAD TROUGHING
SETTLING IN OVER THE EASTERN U.S. THROUGH THIS TIME PERIOD...850MB
TEMPS ARE PROGGED TO DROP INTO THE -4C TO -8C RANGE WHICH WILL
SUPPORT LAKE EFFECT CLOUD COVER AND LAKE EFFECT RAIN DURING THE DAY
AND POSSIBLY LAKE EFFECT SNOW SUNDAY NIGHT AS THE COLDER AIR SLIDES
INTO THE AREA. AT THE TIME BEING THE BEST CHANCE FOR LAKE EFFECT
PRECIPITATION WOULD BE FOR WEST TO WEST NORTHWEST FAVORED AREAS.
AGAIN THIS IS ABOUT A WEEK OUT SO THINGS CAN DEFINITELY CHANGE AND
THE EXACT DETAILS WILL STILL NEED TO BE IRONED OUT AS CONFIDENCE IN
THE MODELS INCREASES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 119 PM EDT TUE OCT 20 2015
OTHER THAN SOME LINGERING STRATUS WHICH COULD BRING AN HOUR OF MVFR
CIGS TO KSAW FROM 18-19Z...EXPECT VFR CONDITIONS AT KIWD/KCMX/KSAW
THRU AT LEAST THE EVENING HOURS AS LOW LEVELS REMAIN DRY. MOISTURE
WILL BEGIN TO INCREASE LATE TONIGHT AS A LOW PRES TROF APPROACHES.
WITH AN UPSLOPE WIND COMPONENT...KCMX/KSAW WILL LIKELY SEE CIGS FALL
TO MVFR LATE TONIGHT INTO WED MORNING WITH THE LOWER CIGS (POSSIBLY
TO LIFR) AT KSAW DUE TO UPSLOPE FLOW ORIGINATING OFF THE WARMER
WATERS OF LAKE MICHIGAN. MVFR CIGS SHOULD SNEAK INTO KIWD LATE IN
THE TAF PERIOD (16-18Z) AS WINDS SHIFT TO A MORE UPSLOPE WSW
DIRECTION.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 305 PM EDT TUE OCT 20 2015
HIGH PRES ACROSS NRN ONTARIO WILL MAINTAIN BRISK NE WINDS IN THE 15-
30KT RANGE ACROSS LAKE SUPERIOR INTO THIS EVENING...STRONGEST OVER
THE WESTERN THIRD OF THE LAKE WHERE THE TERRAIN WILL FUNNEL AND
ENHANCE THE FLOW. WINDS WILL THEN VEER TO THE E-SE TONIGHT/WED
MORNING AS HIGH PRES MOVES TO QUEBEC AND A LOW PRES TROF APPROACHES.
THE STRONGER SE WINDS UP TO 30KT ARE MOST LIKELY OVER THE E HALF OF
THE LAKE ON WED. A LOW PRES CENTER WILL DEVELOP ALONG THE TROF AND
PASS JUST N OF LAKE SUPERIOR WED AFTN. AS THIS OCCURS...A FAVORABLY
ALIGNED PRES RISE/FALL COUPLET WILL GIVE AN ISALLOBARIC BOOST TO THE
WESTERLY WINDS IN THE WAKE OF COLD FROPA. THIS SHOULD RESULT IN A
BRIEF PERIOD OF WESTERLY GALES TO 35 KNOTS ALONG THE TIP AND IN THE
LEE OF THE KEWEENAW LATE WED AFTERNOON/EVENING SO WL INCLUDE A GALE
WARNING FOR LSZ264>266 FOR THIS PERIOD. WINDS WILL SHIFT NW WED
NIGHT THEN DIMINISH THU AS HIGH PRES BUILDS INTO THE UPPER GREAT
LAKES. WINDS WILL THEN BE ON THE INCREASE FRI/SAT AS ANOTHER LOW
PRES TROF SWEEPS THRU THE UPPER GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...KEC
AVIATION...VOSS
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
125 PM EDT TUE OCT 20 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 541 AM EDT TUE OCT 20 2015
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A DEEP MID LEVEL LOW
MOVING FROM HUDSON BAY INTO NRN QUEBEC. TO THE W...A TROF IS OVER
THE ROCKIES IN BOTH THE NRN AND SRN STREAMS. THE NRN STREAM
SHORTWAVE WILL BECOME RATHER VIGOROUS AS IT MOVES INTO THE UPPER
GREAT LAKES AND NRN ONTARIO WED NIGHT. AT THE SFC...COLD FRONT
ASSOCIATED WITH THE DEEP HUDSON BAY MID LEVEL LOW IS MOVING S ACROSS
UPPER MI ATTM. BRISK N TO NE WINDS HAVE DEVELOPED ACROSS LAKE
SUPERIOR BEHIND THE FRONT AND AHEAD OF SFC HIGH PRES BUILDING FROM
NRN MANITOBA INTO NRN ONTARIO. SKIES ARE MOSTLY CLEAR ACROSS THE
FCST AREA EARLY THIS MORNING. A BAND OF STRATOCU BEHIND FRONT IS
CONFINED TO THE E OF LAKE SUPERIOR SO FAR...AND A BKN NARROW BAND OF
MID LEVEL CLOUDS PRODUCING SOME RADAR RETURNS IS LURKING JUST S AND
SW OF MENOMINEE.
INITIALLY TODAY...THERE IS SOME CONCERN THAT A FEW -SHRA COULD BRUSH
THE FAR SCNTRL FCST AREA. PER LATEST RAP...LINGERING STEEP MID LEVEL
LAPSE RATES AND CONVERGENCE OF 850MB FLOW APPEAR TO BE AIDING THE
MID CLOUD/RADAR RETURNS CURRENTLY S AND SW OF MENOMINEE. HRRR RUNS
OVERNIGHT HAVE CONSITENTLY INDICATED THAT THERE WILL BE SOME
NORTHWARD DEVELOPMENT OF -SHRA/SPRINKLES INTO MENOMINEE COUNTY THIS
MORNING/EARLY AFTN. WHILE THERE IS STILL DRY AIR TO OVERCOME IN THE
LOWER LEVELS PER 00Z KGRB SOUNDING...HAVE INTRODUCED ISOLD -SHRA FOR
MENOMINEE COUNTY THIS MORNING BASED ON INCREASING RADAR
REFLECTIVITIES. OTHERWISE...A COOL NE FLOW LOCKS IN TODAY AS HIGH
PRES BUILDS SE ACROSS NRN ONTARIO. AT THIS POINT...WITH POST FRONTAL
STRATOCU REMAINING E OF LAKE SUPERIOR SO FAR AND MOVING SSE...IT
DOES NOT APPEAR THAT A BKN-OVC LOWER CLOUD DECK WILL DEVELOP IN THE
UPSLOPE AREAS TODAY. MAY SEE SOME SCT STRATOCU. OTHERWISE...AFTER A
GENERALLY MOSTLY SUNNY START...HIGH CLOUDS WILL BE ON THE INCREASE
FROM THE W AND SW. OBVIOUSLY WITH THE PASSAGE OF COLD FRONT AND NE
WINDS TODAY...IT WILL BE COOLER TODAY THAN YESTERDAY. EXPECT HIGHS
GENERALLY FROM THE UPPER 40S OVER THE HIGHER TERRAIN OF THE KEWEENAW
AND NCNTRL TO THE LOW/MID 50S ELSEWHERE.
AS SHORTWAVE ENERGY MOVES ACROSS THE NRN PLAINS/SCNTRL CANADA
TONIGHT...850MB WAA DEVELOPS ACROSS THE AREA. HOWEVER...
ISENTROPICALLY...MODELS GENERALLY SUGGEST BETTER MOIST ASCENT TO THE
SE OF THE FCST AREA. MEANWHILE...BEST DEEP LAYER FORCING ASSOCIATED
WITH APPROACHING SHORTWAVE ENERGY IS TO THE NW OF THE FCST AREA. AS
A RESULT...IT APPEARS THE 2 MAIN AREAS OF DEVELOPING PCPN WILL SPLIT
THE FCST AREA TONIGHT...AND THAT IS EXACTLY WHAT THE PCPN FIELDS
FROM THE ALL THE AVBL OPERATIONAL MODELS SHOW. HAVE THUS CUT BACK ON
POPS TONIGHT TO SCHC WITH THE LOWEST POPS ACROSS THE CNTRL FCST
AREA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 445 AM EDT TUE OCT 20 2015
NEAR TO SLIGHTLY ABOVE NORMAL TEMPERATURES THROUGH SATURDAY...THEN
COOLER AIR RETURNS. A PERIOD OF GUSTY WINDS CAN BE EXPECTED
WEDNESDAY AFTERNOON AND EVENING OVER THE KEWEENAW PENINSULA AND
ALONG LAKE SUPERIOR.
WEDNESDAY AND WEDNESDAY NIGHT...A SURFACE LOW AND UPPER LEVEL 500MB
SHORTWAVE STRETCHING FROM MANITOBA...SOUTHWARD INTO MN WILL BEGIN TO
SHIFT EASTWARD TOWARD UPPER PENINSULA. AS THE LOW CENTER SLIDES
ACROSS LAKE SUPERIOR THROUGH THE DAY AND THE ASSOCIATED COLD FRONT
SLIDES THROUGH THE AREA...EXPECT WIDESPREAD RAIN SHOWERS TO DEVELOP.
THE BEST FORCING WILL REMAIN CLOSER TO THE LOW
CENTER...HOWEVER...THERE WILL BE ENOUGH FORCING ACROSS THE REST OF
THE AREA...AS SHOWN BY ANALYZING 1000-500MB RH ALONG WITH DEEP LAYER
QCONV...TO CREATE WIDESPREAD RAIN SHOWERS. THIS LOW WILL QUICKLY
DEPART TO THE EAST OF THE AREA WEDNESDAY EVENING AS IT RAPIDLY
INTENSIFIES AND MUCH DRIER DEEP LAYER AIR SURGES IN BEHIND IT ON
WESTERLY TO NORTHWESTERLY WINDS. THIS WILL ALLOW FOR A VERY QUICK
END TO THE RAIN SHOWERS FROM WEST TO EAST THROUGH THE EVENING HOURS.
ADDITIONALLY...BEHIND THE COLD FRONT...THE PRESSURE GRADIENT WILL
INCREASE BETWEEN THE DEPARTING LOW AND THE HIGH PRESSURE QUICKLY
BUILDING IN BEHIND IT WEDNESDAY NIGHT. THIS WILL ALLOW FOR GUSTY
WEST TO NORTHWESTERLY WINDS. COULD SEE GUSTS UP TO 30 TO 40 MPH OVER
THE KEWEENAW PENINSULA AND NEAR LAKE SUPERIOR IN THE LATE AFTERNOON
AND EVENING HOURS...WITH A BRIEF PERIOD OF GALES POSSIBLE OVER LAKE
SUPERIOR. THIS WILL BE ESPECIALLY TRUE IF STRONGER WINDS MIX DOWN TO
THE SURFACE. WINDS AT 925MB TO 900MB ARE RIGHT AROUND 35 TO 40
KNOTS...AGAIN WITH CAA...IT WILL BE VERY POSSIBLE FOR THESE STRONGER
WINDS TO MIX DOWN...ESPECIALLY OVER THE KEWEENAW PENINSULA AND LAKE
SUPERIOR. THE SHOWERS COULD LINGER A BIT LONGER OVER THE EASTERN
U.P. DUE TO THE PROXIMITY TO THE DEPARTING LOW ALONG WITH CAA INTO
THE AREA. 850MB TEMPERATURES ARE PROGGED TO DROP TO NEAR
-2C LATE WEDNESDAY NIGHT...WITH THE WEST TO NORTHWEST FLOW...WHICH
WILL AT A MINIMUM KEEP THE POTENTIAL FOR LAKE EFFECT CLOUD COVER
OVER THE EAST HALF NEAR LAKE SUPERIOR.
THURSDAY THROUGH FRIDAY...THE GENERAL TREND IS FOR A SURFACE RIDGE
AND ASSOCIATED UPPER LEVEL RIDGE TO QUICKLY BUILD FROM THE NORTHERN
PLAINS AND CANADA INTO THE UPPER GREAT LAKES THURSDAY AND LINGER
THROUGH MOST OF THE DAY FRIDAY. THIS WILL KEEP MAINLY DRY CONDITIONS
IN THE FORECAST. THERE MAY BE SOME LINGERING LOW CLOUDS AS 850MB
TEMPS SLOWLY START TO REBOUND OVER THE EAST AND THE LOW CONTINUES TO
DEPART THROUGH QUEBEC THROUGH THURSDAY AFTERNOON. OTHERWISE...FOR
THE REST OF THE AREA SKIES WILL BE PARTLY CLOUDY THROUGH FRIDAY
MORNING. FRIDAY AFTERNOON...THE NEXT UPPER LEVEL TROUGH AND SURFACE
LOW SLIDING ACROSS SOUTHERN CANADA...ALONG WITH ASSOCIATED COLD
FRONT...WILL APPROACH THE REGION FROM THE WEST. THIS WILL ALLOW FOR
INCREASING CLOUDS FROM THE WEST...HOWEVER...MOST OF THE AREA SHOULD
REMAIN DRY FOR DURING THE DAY FRIDAY.
FRIDAY NIGHT SATURDAY...THE AFOREMENTIONED LOW PRESSURE SYSTEM AND
ASSOCIATED COLD FRONT WILL CONTINUE TO SLIDE EAST ACROSS THE AREA.
MODELS ARE BECOMING MORE SETTLED ON A SOLUTION WITH THE SURFACE LOW
SLIDING FROM NORTHERN MN FRIDAY NIGHT TO NEAR JAMES BAY BY SATURDAY
EVENING. THIS WILL DRAG A COLD FRONT THROUGH THE AREA THROUGH THE
DAY SATURDAY. THERE WILL BE PLENTY OF MOISTURE AND FORCING ALONG THE
FRONT TO ALLOW FOR A RAINY SATURDAY ACROSS MUCH OF THE U.P. ANOTHER
THING TO NOTE...EVEN THOUGH THIS IS STILL SEVERAL DAYS OUT...IS THAT
BOTH THE GFS/EC SHOW THE UPPER LEVEL SHORTWAVE ASSOCIATED WITH THE
TROUGH DIGGING MUCH FARTHER SOUTH THAN THE EARLIER MODEL RUNS. THIS
ACTS TO INTENSIFY THE SURFACE LOW AS THE 500MB SHORTWAVE IS
STAGGERED BACK TO THE WEST OF THE SURFACE LOW. IF THE LOW DOES
INTENSIFY AS PROGGED...WE COULD BE LOOKING AT ANOTHER PERIOD OF
GUSTY WINDS ACROSS THE AREA ON CAA...DUE TO FAIRLY STRONG PRESSURE
GRADIENT ALONG WITH MIXING OF FAIRLY STRONG WINDS DOWN FROM 850MB.
AGAIN THIS IS A WAYS OUT...BUT DEFINITELY SOMETHING TO KEEP IN MIND.
SATURDAY NIGHT THROUGH THE EXTENDED...THE GFS/EC BOTH AGREE ON A
DECENT RIDGE BUILDING OVER THE WESTERN CONUS WITH BROAD TROUGHING
SETTLING IN OVER THE EASTERN U.S. THROUGH THIS TIME PERIOD...850MB
TEMPS ARE PROGGED TO DROP INTO THE -4C TO -8C RANGE WHICH WILL
SUPPORT LAKE EFFECT CLOUD COVER AND LAKE EFFECT RAIN DURING THE DAY
AND POSSIBLY LAKE EFFECT SNOW SUNDAY NIGHT AS THE COLDER AIR SLIDES
INTO THE AREA. AT THE TIME BEING THE BEST CHANCE FOR LAKE EFFECT
PRECIPITATION WOULD BE FOR WEST TO WEST NORTHWEST FAVORED AREAS.
AGAIN THIS IS ABOUT A WEEK OUT SO THINGS CAN DEFINITELY CHANGE AND
THE EXACT DETAILS WILL STILL NEED TO BE IRONED OUT AS CONFIDENCE IN
THE MODELS INCREASES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 119 PM EDT TUE OCT 20 2015
OTHER THAN SOME LINGERING STRATUS WHICH COULD BRING AN HOUR OF MVFR
CIGS TO KSAW FROM 18-19Z...EXPECT VFR CONDITIONS AT KIWD/KCMX/KSAW
THRU AT LEAST THE EVENING HOURS AS LOW LEVELS REMAIN DRY. MOISTURE
WILL BEGIN TO INCREASE LATE TONIGHT AS A LOW PRES TROF APPROACHES.
WITH AN UPSLOPE WIND COMPONENT...KCMX/KSAW WILL LIKELY SEE CIGS FALL
TO MVFR LATE TONIGHT INTO WED MORNING WITH THE LOWER CIGS (POSSIBLY
TO LIFR) AT KSAW DUE TO UPSLOPE FLOW ORIGINATING OFF THE WARMER
WATERS OF LAKE MICHIGAN. MVFR CIGS SHOULD SNEAK INTO KIWD LATE IN
THE TAF PERIOD (16-18Z) AS WINDS SHIFT TO A MORE UPSLOPE WSW
DIRECTION. &&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 541 AM EDT TUE OCT 20 2015
HIGH PRES BUILDING SE ACROSS NRN ONTARIO WILL LEAD TO BRISK NE WINDS
IN THE 15-30KT RANGE ACROSS LAKE SUPERIOR TODAY. WINDS WILL BE
STRONGEST OVER WESTERN LAKE SUPERIOR WHERE THE TERRAIN WILL FUNNEL
AND ENHANCE THE FLOW. WINDS WILL THEN VEER TO THE E-SE TONIGHT/WED
MORNING AS HIGH PRES MOVES TO QUEBEC AND A LOW PRES TROF APPROACHES.
THE STRONGER SE WINDS UP TO 30KT ARE MOST LIKELY OVER THE E HALF OF
THE LAKE ON WED. A LOW PRES CENTER WILL DEVELOP ALONG THE TROF AND
PASS JUST N OF LAKE SUPERIOR WED AFTN. AS THIS OCCURS...A FAVORABLY
ALIGNED PRES RISE/FALL COUPLET WILL GIVE AN ISALLOBARIC BOOST TO THE
WESTERLY WINDS IN THE WAKE OF COLD FROPA. RESULT SHOULD BE A FEW HRS
OF SOME GALE FORCE GUSTS AROUND THE W SIDE OF THE KEWEENAW LATE WED
AFTN/EVENING AND THEN OVER THE ERN PART OF THE LAKE WED EVENING. FOR
NOW...HELD OFF ON A GALE WATCH GIVEN THIS NEW MODEL TREND FOR
STRONGER WINDS. WINDS WILL SHIFT NW WED NIGHT THEN DIMINISH THU AS
HIGH PRES BUILDS INTO THE UPPER GREAT LAKES. WINDS WILL THEN BE ON
THE INCREASE FRI/SAT AS ANOTHER LOW PRES TROF SWEEPS THRU THE UPPER
GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KEC
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
1124 AM PDT TUE OCT 20 2015
.SYNOPSIS...A LOW PRESSURE SYSTEM WILL BECOME CENTERED NEAR YUMA
ARIZONA TODAY AND BRING SHOWERS AND ISOLATED THUNDERSTORMS THROUGH
THE MIDDLE OF THE WEEK...MAINLY TO NORTHWEST ARIZONA AND NEARBY
AREAS OF SOUTHEAST NEVADA AND CALIFORNIA. SLIGHTLY BELOW NORMAL
TEMPERATURES CAN BE EXPECTED THIS WEEK ALONG WITH NORTH BREEZES
TUESDAY AND WEDNESDAY.
&&
.UPDATE...
DID A QUICK UPDATE TO REDUCE POPS ACROSS MOST AREAS FOR THE NEXT FEW
HOURS AS NOT MUCH IS GOING ON EXCEPT FOR MOHAVE COUNTY. STARTING TO
SEE SOME CELLS TRYING TO FORM ACROSS CENTRAL MOHAVE COUNTY.
ELSEWHERE, CUMULUS DEVELOPMENT IS NOTICEABLE ON MOST OF THE TERRAIN
ACROSS THE REGION. WE WILL SEE HOW THESE MATERIALIZE FOR THIS
AFTERNOON. NOT REALLY EXPECTING ANY MORE UPDATES BETWEEN NOW AND THE
FINAL AFTERNOON FORECAST.
&&
.PREVIOUS UPDATE...
939 AM PDT TUE OCT 20 2015
ANOTHER UPDATE TO ADJUST POPS, QPF, SKY COVER, AND TEMPS FOR THIS
AFTERNOON. THE PRECIP AND CLOUD COVER ACROSS SOUTHERN MOHAVE COUNTY
WILL LIMIT WARMING, SO LOWERED EXPECTED AFTERNOON HIGHS BY A COUPLE
DEGREES. THERE ARE ENOUGH BREAKS IN THE CLOUDS ACROSS CLARK COUNTY
THAT WE MAY REALIZE OUR CURRENT FORECAST OF MIDDLE 70S FOR LAS
VEGAS, BUT CURRENT BAND OF CLOUDS DRAPED OVER THE VALLEY WILL SLOW
THAT PROCESS. HAVE CONTINUED SLIGHT CHANCE POPS FOR THE LAS VEGAS
VALLEY, AS SOME DIURNAL SHOWERS (PERHAPS A STORM) MAY GET IN HERE
LATER THIS AFTERNOON AND EARLY EVENING.
&&
.PREVIOUS UPDATE...
800 AM PDT TUE OCT 20 2015
QUICK UPDATE TO ADJUST POPS, WEATHER, SKY COVER, AND QPF, MAINLY TO
ACCOUNT FOR THE ONGOING LINE OF THUNDERSTORMS ACROSS SOUTHEAST
MOHAVE COUNTY, NEAR WIKIEUP. THE REST OF THE FORECAST FOR TODAY
LOOKS GOOD, ACCORDING TO THE LATEST GUIDANCE.
&&
.PREVIOUS DISCUSSION...
232 AM PDT TUE OCT 20 2015
.SHORT TERM...TODAY THROUGH THURSDAY NIGHT.
NOW...A VIGOROUS SHORTWAVE HAS ROUNDED THE BASE OF THE LONGWAVE
TROUGH DRAPED ACROSS THE WESTERN CONUS. THIS HAS RESULTED IN AN AREA
OF UPWARD FORCING AND CONVECTION ACROSS WESTERN ARIZONA. DISCRETE
SUPERCELLS WERE NOTED OVER YAVAPAI COUNTY BETWEEN 06Z-07Z WHICH THEN
MOVED INTO SOUTHEASTERN MOHAVE COUNTY WHERE THEY WEAKENED DUE TO
LIMITED INSTABILITY. STILL...MODERATE CONVECTION CONTINUE ACROSS THE
EASTERN HALF OF THE COUNTY.
TODAY...LAST SEVERAL RUNS OF THE HRRR HAVE INDICATED THE
DEVELOPMENT OF AN AREA OF SHOWERS WITH EMBEDDED STORMS OR EVEN A
MESOSCALE CONVECTIVE VORTEX (MCV) OVER SOUTHERN MOHAVE COUNTY
BETWEEN 12Z-15Z THIS MORNING. THIS ACTIVITY IS THEN FORECAST TO MOVE
NORTH-NORTHWEST THROUGH MID-DAY BEFORE WEAKENING. THIS WOULD THEN BE
FOLLOWED BY THE DEVELOPMENT OF DIURNALLY DRIVEN STORMS ALONG AND
SOUTH OF THE I-15 CORRIDOR. YESTERDAY`S GUIDANCE INDICATED THE
POTENTIAL FOR A PUSH OF COLD POOL DRIVEN CONVECTION WESTWARD OUT OF
MOHAVE COUNTY THIS EVENING...HOWEVER THE MOST RECENT GUIDANCE HAS
BACKED OFF ON THAT IDEA...DISSIPATING CONVECTION AFTER SUNSET. HAVE
HELD ON TO A SLIGHT CHANCE OF CONVECTION OVERNIGHT FROM LAS VEGAS
EAST...BUT COVERAGE IS EXPECTED TO BE VERY ISOLATED. OUTSIDE OF
CONVECTION...GUSTY NORTH WINDS ARE EXPECTED FROM THE COLORADO RIVER
VALLEY WEST IN THE AS ANOTHER AS SHORTWAVES REINFORCE THE GRADIENT
ACROSS THE REGION.
WEDNESDAY...CONVECTION IS EXPECTED TO BECOME CONFINED TO MOHAVE
COUNTY...AND WILL LARGELY BE DIURNALLY DRIVEN DURING THE AFTERNOON.
GUSTY NORTH WINDS WILL CONTINUE FOR MOST AREAS IN THE FORECAST AREA.
THURSDAY...CONVECTION CHANCES CONTINUE TO DECREASE...AND WILL BE
LIMITED TO NORTHERN MOHAVE AND EASTERN LINCOLN COUNTIES. WINDS
EXPECTED TO DIMINISH BY THURSDAY.
TEMPERATURES WILL REMAIN SLIGHTLY BELOW NORMAL...BUT WITH A SLOW
WARMING TREND THROUGH THE SHORT TERM PERIOD.
.LONG TERM...FRIDAY THROUGH MONDAY.
DRY CONDITIONS WITH NORTHWEST TO QUASI-ZONAL FLOW ARE EXPECTED
ACROSS THE AREA THROUGH THE MAJORITY OF THE LONG TERM PERIOD.
EMBEDDED SHORTWAVES WILL BRING OCCASIONALLY BREEZY CONDITIONS TO THE
REGION THROUGH THE WEEKEND. TEMPERATURES WILL REMAIN NEAR TO
SLIGHTLY BELOW NORMAL.
&&
.AVIATION...FOR MCCARRAN...LIGHT AND VARIABLE WINDS WILL BEGIN TO
FAVOR A NORTHWEST AND THEN NORTH DIRECTION THROUGH THE MORNING HOURS
AS SPEEDS INCREASE TO AROUND 8-12 KTS. OCCASIONAL GUSTS WILL BE
POSSIBLE. SLIGHT CHANCE OF SHRA OR POSSIBLY AND ISOLATED TS THIS
AFTERNOON/EVENING...HOWEVER CHANCES ARE TOO LOW TO MENTION IN THE
12Z TAF. CIGS GENERALLY EXPECTED TO REMAIN AOA 8K FEET. WINDS ARE
EXPECTED TO CONTINUE TO FAVOR A NORTHERLY DIRECTION THROUGH
WEDNESDAY.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...SHRA/TSRA THIS MORNING OVER MOHAVE COUNTY. EXPECT AT
LEAST SHRA AND POSSIBLY TS ACTIVITY TO SPREAD NORTH AND
EAST...THROUGH THE MORNING. DRY CONDITIONS EXPECTED WEST OF A LINE
FROM KELY-KDRA-KNXP LINE. WINDS EXPECTED TO FAVOR A NORTH DIRECTION
ACROSS MOST OF THE REGION TODAY...WITH SPEEDS 10-20 KTS AND GUSTS
20-30 KTS. SHRA/TSRA ACTIVITY WILL BE CONFINED MAINLY TO MOHAVE
COUNTY WEDNESDAY...GUSTY NORTH WINDS WILL CONTINUE.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION IS NOT EXPECTED
TODAY. HOWEVER...SPOTTERS ARE ENCOURAGED TO REPORT ACCORDING TO
STANDARD OPERATING PROCEDURES.
&&
$$
UPDATES...PADDOCK
PREV DISCUSSION...WOLCOTT
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
939 AM PDT TUE OCT 20 2015
.SYNOPSIS...A LOW PRESSURE SYSTEM WILL BECOME CENTERED NEAR YUMA
ARIZONA TODAY AND BRING SHOWERS AND ISOLATED THUNDERSTORMS THROUGH
THE MIDDLE OF THE WEEK...MAINLY TO NORTHWEST ARIZONA AND NEARBY
AREAS OF SOUTHEAST NEVADA AND CALIFORNIA. SLIGHTLY BELOW NORMAL
TEMPERATURES CAN BE EXPECTED THIS WEEK ALONG WITH NORTH BREEZES
TUESDAY AND WEDNESDAY.
&&
.UPDATE...
ANOTHER UPDATE TO ADJUST POPS, QPF, SKY COVER, AND TEMPS FOR THIS
AFTERNOON. THE PRECIP AND CLOUD COVER ACROSS SOUTHERN MOHAVE COUNTY
WILL LIMIT WARMING, SO LOWERED EXPECTED AFTERNOON HIGHS BY A COUPLE
DEGREES. THERE ARE ENOUGH BREAKS IN THE CLOUDS ACROSS CLARK COUNTY
THAT WE MAY REALIZE OUR CURRENT FORECAST OF MIDDLE 70S FOR LAS
VEGAS, BUT CURRENT BAND OF CLOUDS DRAPED OVER THE VALLEY WILL SLOW
THAT PROCESS. HAVE CONTINUED SLIGHT CHANCE POPS FOR THE LAS VEGAS
VALLEY, AS SOME DIURNAL SHOWERS (PERHAPS A STORM) MAY GET IN HERE
LATER THIS AFTERNOON AND EARLY EVENING.
&&
.PREVIOUS UPDATE...
800 AM PDT TUE OCT 20 2015
QUICK UPDATE TO ADJUST POPS, WEATHER, SKY COVER, AND QPF, MAINLY TO
ACCOUNT FOR THE ONGOING LINE OF THUNDERSTORMS ACROSS SOUTHEAST
MOHAVE COUNTY, NEAR WIKIEUP. THE REST OF THE FORECAST FOR TODAY
LOOKS GOOD, ACCORDING TO THE LATEST GUIDANCE.
&&
.PREVIOUS DISCUSSION...
232 AM PDT TUE OCT 20 2015
.SHORT TERM...TODAY THROUGH THURSDAY NIGHT.
NOW...A VIGOROUS SHORTWAVE HAS ROUNDED THE BASE OF THE LONGWAVE
TROUGH DRAPED ACROSS THE WESTERN CONUS. THIS HAS RESULTED IN AN AREA
OF UPWARD FORCING AND CONVECTION ACROSS WESTERN ARIZONA. DISCRETE
SUPERCELLS WERE NOTED OVER YAVAPAI COUNTY BETWEEN 06Z-07Z WHICH THEN
MOVED INTO SOUTHEASTERN MOHAVE COUNTY WHERE THEY WEAKENED DUE TO
LIMITED INSTABILITY. STILL...MODERATE CONVECTION CONTINUE ACROSS THE
EASTERN HALF OF THE COUNTY.
TODAY...LAST SEVERAL RUNS OF THE HRRR HAVE INDICATED THE
DEVELOPMENT OF AN AREA OF SHOWERS WITH EMBEDDED STORMS OR EVEN A
MESOSCALE CONVECTIVE VORTEX (MCV) OVER SOUTHERN MOHAVE COUNTY
BETWEEN 12Z-15Z THIS MORNING. THIS ACTIVITY IS THEN FORECAST TO MOVE
NORTH-NORTHWEST THROUGH MID-DAY BEFORE WEAKENING. THIS WOULD THEN BE
FOLLOWED BY THE DEVELOPMENT OF DIURNALLY DRIVEN STORMS ALONG AND
SOUTH OF THE I-15 CORRIDOR. YESTERDAY`S GUIDANCE INDICATED THE
POTENTIAL FOR A PUSH OF COLD POOL DRIVEN CONVECTION WESTWARD OUT OF
MOHAVE COUNTY THIS EVENING...HOWEVER THE MOST RECENT GUIDANCE HAS
BACKED OFF ON THAT IDEA...DISSIPATING CONVECTION AFTER SUNSET. HAVE
HELD ON TO A SLIGHT CHANCE OF CONVECTION OVERNIGHT FROM LAS VEGAS
EAST...BUT COVERAGE IS EXPECTED TO BE VERY ISOLATED. OUTSIDE OF
CONVECTION...GUSTY NORTH WINDS ARE EXPECTED FROM THE COLORADO RIVER
VALLEY WEST IN THE AS ANOTHER AS SHORTWAVES REINFORCE THE GRADIENT
ACROSS THE REGION.
WEDNESDAY...CONVECTION IS EXPECTED TO BECOME CONFINED TO MOHAVE
COUNTY...AND WILL LARGELY BE DIURNALLY DRIVEN DURING THE AFTERNOON.
GUSTY NORTH WINDS WILL CONTINUE FOR MOST AREAS IN THE FORECAST AREA.
THURSDAY...CONVECTION CHANCES CONTINUE TO DECREASE...AND WILL BE
LIMITED TO NORTHERN MOHAVE AND EASTERN LINCOLN COUNTIES. WINDS
EXPECTED TO DIMINISH BY THURSDAY.
TEMPERATURES WILL REMAIN SLIGHTLY BELOW NORMAL...BUT WITH A SLOW
WARMING TREND THROUGH THE SHORT TERM PERIOD.
.LONG TERM...FRIDAY THROUGH MONDAY.
DRY CONDITIONS WITH NORTHWEST TO QUASI-ZONAL FLOW ARE EXPECTED
ACROSS THE AREA THROUGH THE MAJORITY OF THE LONG TERM PERIOD.
EMBEDDED SHORTWAVES WILL BRING OCCASIONALLY BREEZY CONDITIONS TO THE
REGION THROUGH THE WEEKEND. TEMPERATURES WILL REMAIN NEAR TO
SLIGHTLY BELOW NORMAL.
&&
.AVIATION...FOR MCCARRAN...LIGHT AND VARIABLE WINDS WILL BEGIN TO
FAVOR A NORTHWEST AND THEN NORTH DIRECTION THROUGH THE MORNING HOURS
AS SPEEDS INCREASE TO AROUND 8-12 KTS. OCCASIONAL GUSTS WILL BE
POSSIBLE. SLIGHT CHANCE OF SHRA OR POSSIBLY AND ISOLATED TS THIS
AFTERNOON/EVENING...HOWEVER CHANCES ARE TOO LOW TO MENTION IN THE
12Z TAF. CIGS GENERALLY EXPECTED TO REMAIN AOA 8K FEET. WINDS ARE
EXPECTED TO CONTINUE TO FAVOR A NORTHERLY DIRECTION THROUGH
WEDNESDAY.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...SHRA/TSRA THIS MORNING OVER MOHAVE COUNTY. EXPECT AT
LEAST SHRA AND POSSIBLY TS ACTIVITY TO SPREAD NORTH AND
EAST...THROUGH THE MORNING. DRY CONDITIONS EXPECTED WEST OF A LINE
FROM KELY-KDRA-KNXP LINE. WINDS EXPECTED TO FAVOR A NORTH DIRECTION
ACROSS MOST OF THE REGION TODAY...WITH SPEEDS 10-20 KTS AND GUSTS
20-30 KTS. SHRA/TSRA ACTIVITY WILL BE CONFINED MAINLY TO MOHAVE
COUNTY WEDNESDAY...GUSTY NORTH WINDS WILL CONTINUE.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION IS NOT EXPECTED
TODAY. HOWEVER...SPOTTERS ARE ENCOURAGED TO REPORT ACCORDING TO
STANDARD OPERATING PROCEDURES.
&&
$$
UPDATES...PADDOCK
PREV DISCUSSION...WOLCOTT
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
555 PM CDT TUE OCT 20 2015
.UPDATE...
ISSUED AT 551 PM CDT TUE OCT 20 2015
AS OF 2330 UTC...THE OCCLUDING FRONT WAS PROPAGATING EAST ACROSS
THE US HIGHWAY 83 CORRIDOR...WITH BREEZY CONDITIONS AND STRATUS IN
TRAIL. INCREASED POPS ACROSS THE NORTH CENTRAL ASSOCIATED WITH THE
UPPER LEVEL VORTICITY MAXIMA THIS EVENING IN ACCORDANCE WITH
RADAR TRENDS AND A TIME LAGGED ENSEMBLE OF THE HRRR THROUGH ITS 22
UTC ITERATION
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 232 PM CDT TUE OCT 20 2015
BREEZY TO WINDY CONDITIONS HIGHLIGHT THE SHORT TERM PERIOD WITH
SCATTERED SHOWERS MAINLY WEST AND NORTH THROUGH TONIGHT.
CURRENTLY...SURFACE LOW PRESSURE WAS LOCATED OVER WEST CENTRAL
NORTH DAKOTA...WITH UPPER LEVEL CIRCULATION NOTED OVER NORTHWEST
NORTH DAKOTA. THIS ELONGATED UPPER LEVEL TROUGH THAT EXTENDS INTO
THE DESERT SOUTHWEST WILL CONTINUE TO SHEAR OUT AS THE NORTHERN
STREAM AND SOUTHERN STREAM ENERGY SEPARATES.
TONIGHT...THE NORTHERN STREAM TROUGH AND ASSOCIATED SURFACE LOW
WILL TRACK EAST ACROSS THE STATE...SPREADING SCATTERED SHOWERS
ACROSS THE WEST AND NORTH CENTRAL THIS EVENING...AND INTO THE
EARLY OVERNIGHT HOURS. AS THE SURFACE AND UPPER LOWS EXIT...DECENT
SURFACE GRADIENT WINDS...AIDED BY AN ISALLOBARIC COMPONENT SHOULD
SUPPORT GUST WINDS OVERNIGHT...AND INTO THE MORNING ACROSS THE
JAMES RIVER VALLEY INTO THE TURTLE MOUNTAINS.
WEDNESDAY...HIGH PRESSURE BUILDS OVER THE AREA BEHIND THE EXITING
NORTHERN STREAM SYSTEM. NORTHWEST WINDS WILL DIMINISH EAST...AND
LIGHT WINDS WEST WILL SHIFT TO THE SOUTH AHEAD OF THE NEXT SYSTEM
THAT MOVES INTO THE AREA LATE THURSDAY.
AFTER LOWS TONIGHT OF 35 NORTHWEST TO 45 SOUTHEAST...EXPECT HIGHS
WEDNESDAY FROM THE MID 50S TO LOWER 60S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 232 PM CDT TUE OCT 20 2015
THE LONG TERM IS HIGHLIGHTED BY A POTENT STORM SYSTEM
THURSDAY/FRIDAY.
A COLORADO LOW WILL SWING THROUGH THE NORTHERN PLAINS THURSDAY
NIGHT AND FRIDAY. WIDESPREAD RAIN IS EXPECTED TO BEGIN AHEAD OF
THE LOW THURSDAY EVENING. THE 12 UTC GFS/SREF/ECMWF ALL HAVE THE
CENTER TRAVERSING THE ND/SD BORDER BY FRIDAY. THIS TRACK WOULD
KEEP DEFORMATION BANDED PRECIPITATION MAINLY ACROSS NORTHERN NORTH
DAKOTA. THE LOW IS FORECAST TO QUICKLY PROPAGATE OFF TO THE EAST
AS IT GETS CAUGHT UP IN THE NORTHERN STREAM...BRINGING AN END TO
PRECIPITATION BY LATE FRIDAY EVENING. TOTAL LIQUID ACCUMULATION
IS EXPECTED TO RANGE FROM 0.25 INCHES TO 0.75 INCHES.
COLD AIR ADVECTION BEHIND THE LOW MAY BE ENOUGH TO BRIEFLY
TRANSITION SOME RAIN TO SNOW. HOWEVER...NO ACCUMULATION IS
EXPECTED AT THIS TIME.
THE REST OF THE LONG TERM APPEARS COOL WITH TEMPERATURES IN THE
50S DURING THE DAY AND 20S/30S AT NIGHT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 551 PM CDT TUE OCT 20 2015
WIDESPREAD MVFR CONDITIONS THIS EVENING AND TONIGHT IN STRATUS
BEHIND AN OCCLUDING FRONT ACROSS CENTRAL NORTH DAKOTA THIS EVENING
THAT WILL CONTINUE TO MOVE EAST THROUGH THE NIGHT. BREEZY
NORTHWEST WINDS WITH GUSTS OF 25-30 KTS ARE EXPECTED TONIGHT AREA
WIDE BEHIND THE FRONT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...TWH
LONG TERM...AJ
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
254 PM CDT TUE OCT 20 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 254 PM CDT TUE OCT 20 2015
AREA OF SHOWERS AND THUNDERSTORMS ACROSS SOUTHERN IOWA CONTINUES
TO ADVANCE TO THE EAST/NORTHEAST WITH ADDITIONAL DEVELOPMENT
OCCURRING OVER THE FAR NORTHEAST CORNER OF ILLINOIS. THIS ACTIVITY
WAS OCCURRING SOUTH AND EAST OF A FRONT THAT STRETCH ACROSS
CENTRAL WISCONSIN INTO MINNESOTA AND AHEAD OF A SHORT WAVE TROUGH
WORKING ACROSS EASTERN KANSAS AND NORTHERN MISSOURI. THE TREND IN
THE LAST FEW RUNS OF THE HRRR HAS BEEN TO CONTINUE TO BRING THE
ACTIVITY OVER IOWA TO THE NORTHEAST AND JOINING UP WITH THE
DEVELOPING ACTIVITY OVER ILLINOIS. THE 20.17Z RUN OF THE HRRR
INDICATES THE BULK OF THE ACTIVITY WILL STAY TO THE SOUTH BUT THAT
THE FAR SOUTHERN SECTIONS COULD GET BRUSHED LATE THIS AFTERNOON
INTO EARLY THIS EVENING. WILL CARRY SOME 20 TO 30 PERCENT RAIN
CHANCES OVER THIS AREA THROUGH THE EARLY EVENING.
THE FRONT IS THEN EXPECTED TO WORK SOUTH THROUGH THE AREA LATE
TONIGHT THROUGH WEDNESDAY. ANY FORCING FOR SHOWERS ALONG THE FRONT
LOOKS TO BE PRIMARILY TO THE NORTH OF THE AREA CLOSER TO THE MAIN
SHORT WAVE TROUGH AND SURFACE LOW. CANNOT TOTALLY RULE OUT
SOMETHING POPPING UP ALONG THE FRONT...SO WILL CARRY SOME SMALL
RAIN CHANCES LATE TONIGHT THROUGH WEDNESDAY FOR THIS POSSIBILITY.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 254 PM CDT TUE OCT 20 2015
THE UPPER LEVEL LOW OVER THE DESERT SOUTHWEST WILL BECOME AN OPEN
WAVE AND START TO MOVE UP THE BACK SIDE OF THE UPPER LEVEL RIDGE
AXIS IN PLACE OVER THE CENTRAL PART OF THE COUNTRY. STILL SOME
DIFFERENCES IN HOW QUICKLY THIS SYSTEM OPENS UP AND STARTS TO
EJECT TOWARD THE AREA. THE 20.12Z GFS IS THE QUICKEST TO START
BRINGING SHORT WAVE ENERGY INTO THE AREA AND WOULD INDICATE THERE
COULD BE A CHANCE FOR RAIN ALREADY LATE THURSDAY NIGHT. THE 20.12Z
ECMWF IS SLOWER WITH THIS PROCESS AND HOLDS THE SHORT WAVE TROUGHS
BACK INTO THE MISSOURI RIVER VALLEY THROUGH THURSDAY NIGHT. GIVEN
THAT THE MODELS HAVE A BIAS OF BEING TOO QUICK TO EJECT OUT SYSTEM
FROM THE SOUTHWEST...HAVE CONTINUED WITH THE SLOWER MODEL TRENDS
AND WILL START TO BRING THE RAIN CHANCES IN FRIDAY. THE GENERAL
MODEL CONSENSUS TAKES THE MAIN SHORT WAVE TROUGH PAST THE AREA
JUST TO THE NORTHWEST OF THE AREA. WITH THIS TRACK...BOTH THE
ECMWF AND GFS INDICATE A PERIOD OF MODERATE TO STRONG PV ADVECTION
IN THE 500-300 MB LAYER FOR FRIDAY AFTERNOON AND EVENING. GOOD
MOISTURE TRANSPORT OFF THE GULF OF MEXICO SHOULD OCCUR WITH THIS
SYSTEM. THE CONCERN WITH THIS IS WHETHER THE AXIS OF MOISTURE
TRANSPORT WILL BE THROUGH THE AREA TO GET AHEAD OF THE MAIN SHORT
WAVE TROUGH AS THE GFS SUGGESTS OR IF THERE WILL BE A COUPLE OF
BRANCHES WITH ONE TO THE NORTH AND ANOTHER INTO THE AREA LIKE THE
ECMWF. EITHER WAY...THERE WILL BE A PERIOD OF GOOD CONVERGENCE
OVER THE AREA ALONG THE EASTERN SIDE OF THE MOISTURE TRANSPORT
AXIS AS THIS MOVES THROUGH FRIDAY AFTERNOON. THE BEST RAIN CHANCES
WILL THEN GRADUALLY MOVE EAST FRIDAY NIGHT AS THE FORCING AND
MOISTURE TRANSPORT SHIFTS TO THE EAST AS WELL. SOME LINGERING
CHANCE FOR RAIN INTO SATURDAY MORNING...MAINLY ACROSS THE EASTERN
SECTIONS.
THE FLOW BEHIND THIS SYSTEM BECOMES MORE ZONAL TO HAVING A SLIGHT
NORTHWEST COMPONENT TO IT. THE MODELS ARE SUGGESTING SEVERAL
NORTHERN STREAM SHORT WAVE TROUGHS WILL BE EMBEDDED IN THIS FLOW
AND COULD START TO COME ACROSS THE UPPER MIDWEST SUNDAY NIGHT AND
MONDAY WITH ANOTHER FOR MONDAY NIGHT INTO TUESDAY. THESE CERTAINLY
DO NOT LOOK LIKE BIG PRECIPITATION MAKERS AT THIS POINT BUT
TEMPERATURES WILL BE COOL ENOUGH FOR A POSSIBILITY OF SOME SNOW TO
MIX IN LATE AT NIGHT INTO THE EARLY MORNING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1259 PM CDT TUE OCT 20 2015
VFR CONDITIONS ARE EXPECTED THROUGH THE FORECAST PERIOD. A WEAK
FRONTAL BOUNDARY WILL DROP SOUTH ACROSS THE TAF SITES LATE THIS
AFTERNOON INTO THIS EVENING AND INTERACT WITH A SHORTWAVE. THIS
WILL PRODUCE SHOWERS AND PERHAPS AN ISOLATED THUNDERSTORM ACROSS
PORTIONS OF NORTHEAST IOWA INTO EXTREME SOUTHWEST WISCONSIN. THE
IMPACT TO THE TAFS WILL BE AN INCREASE IN SCT TO BKN MID TO HIGH
LEVEL CLOUDS. A COLD FRONT THEN PUSHES THROUGH FROM WEST TO EAST
BY MID TO LATE WEDNESDAY MORNING WITH WINDS SWITCHING TO THE
WEST/NORTHWEST AND INCREASING TO 10 TO 14 KTS WITH GUSTS TO 22 KTS
POSSIBLE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...WETENKAMP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1259 PM CDT TUE OCT 20 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 216 AM CDT TUE OCT 20 2015
AT 3 AM...A SURFACE LOW WAS LOCATED OVER SOUTHWEST MINNESOTA. A
STATIONARY FRONT EXTENDED EAST FROM THIS LOW FROM FARIBAULT
MINNESOTA TO GREEN BAY WISCONSIN. NORTH OF THIS FRONT TEMPERATURES
WERE IN THE 40S AND 50S. MEANWHILE SOUTH OF THIS FRONT...
TEMPERATURES RANGED FROM THE UPPER 50S TO MID 60S WHICH IS WARMER
THAN OUR NORMAL HIGH TEMPERATURES FOR MID OCTOBER.
FOR THIS AFTERNOON AND EVENING...THE 10.20Z MODELS ARE IN GENERAL
AGREEMENT THAT A SHORT WAVE TROUGH...CURRENTLY LOCATED OVER
EASTERN KANSAS WILL MOVE NORTHEAST INTO EASTERN IOWA THIS
AFTERNOON...AND NORTHERN ILLINOIS AND SOUTHERN WISCONSIN THIS
EVENING. AHEAD OF THIS WAVE...ELEVATED CAPES WILL CLIMB TO AROUND
500 J/KG ACROSS NORTHEAST IOWA AND SOUTHWEST WISCONSIN DURING THE
LATE AFTERNOON AND EVENING. THIS SHOULD BE ENOUGH INSTABILITY FOR
ISOLATED TO SCATTERED SHOWERS TO DEVELOP BETWEEN 20.21Z AND
21.03Z. THE ARW...NMM...AND HRRR COMPOSITE REFLECTIVITY PRODUCT
EVEN HINTS THAT THERE COULD BE SOME ISOLATED THUNDERSTORMS ACROSS
SOUTH CENTRAL AND SOUTHEAST WISCONSIN AND NORTHERN ILLINOIS.
COMPARING THE CURRENT TEMPERATURES TO THE GRIDDED MODEL VALUES...
THE MODELS ARE NOT DOING THAT WELL THIS MORNING ALONG AND SOUTH OF
INTERSTATE 94. THE GRIDDED MINIMUM TEMPERATURES WILL END UP BEING
TOO COLD. PARTLY SUNNY SKIES TODAY WILL ALLOW US TO MIX UP TO
900 MB THIS AFTERNOON. WITH THE GROUND BEING VERY DRY DUE TO THE
LACK OF RAIN DURING THE PAST MONTH...EXPECT THE THERE WILL BE A
SUPER ADIABATIC LAPSE RATE UP TO 900 MB. THIS WILL RESULT IN HIGH
TEMPERATURES IN THESE AREAS CLIMBING INTO THE MID 70S. THIS WILL
BE ABOUT 5 TO 10 DEGREES SHY OF THE RECORDS FOR TODAY. MOST
PLACES HAVE THEIR HIGH TEMPERATURES IN THE LOWER TO MID 80S WHICH
OCCURRED IN 1953...2000...OR 2003.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 216 AM CDT TUE OCT 20 2015
ON WEDNESDAY MORNING...THE 20.00Z MODELS ARE IN GOOD AGREEMENT
THAT A COLD FRONT WILL MOVE THROUGH THE AREA. WITH THE BEST LIFT
AND MOISTURE TRANSPORT BEING TO OUR NORTH AND SOUTHEAST...NOT
SEEING MUCH CHANCE OF PRECIPITATION ALONG IT...SO LOWERED THE RAIN
CHANCES ACROSS WESTERN WISCONSIN TO 20 PERCENT.
FROM FRIDAY INTO SATURDAY...THE MODELS ARE IN GOOD AGREEMENT THAT
THE CLOSED 500 MB LOW...CURRENTLY OVER THE SOUTHWEST UNITED
STATES...WILL LIFT NORTHEAST OUT OF THE CENTRAL AND SOUTHERN
PLAINS ON FRIDAY...MINNESOTA AND WISCONSIN ON FRIDAY NIGHT...AND
THE GREAT LAKES ON SATURDAY. THIS SYSTEM WILL TAP INTO GULF OF
MEXICO AND TROPICAL MOISTURE AS IT MOVES THROUGH THE REGION.
PRECIPITABLE WATER VALUES CLIMB UP TO 1.5 INCHES ON FRIDAY
AFTERNOON /THIS IS 1 TO 2 STANDARD DEVIATIONS ABOVE NORMAL/...AND
THEN QUICKLY DECLINES AS THE COLD FRONT MOVES QUICKLY EAST THROUGH
THE REGION. WITH THE BEST FORCING AND MOISTURE TRANSPORT BEING TO
OUR NORTH AND SOUTHEAST...THE HEAVIEST RAIN MAY MISS OUR AREA.
EVEN IF WE DID SEE SOME HEAVY RAIN...IT SHOULD NOT CREATE ANY
ISSUES BECAUSE IT WILL BE A BRIEF PERIOD AND THAT IT HAS BEEN DRY
SO LONG.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1259 PM CDT TUE OCT 20 2015
VFR CONDITIONS ARE EXPECTED THROUGH THE FORECAST PERIOD. A WEAK
FRONTAL BOUNDARY WILL DROP SOUTH ACROSS THE TAF SITES LATE THIS
AFTERNOON INTO THIS EVENING AND INTERACT WITH A SHORTWAVE. THIS
WILL PRODUCE SHOWERS AND PERHAPS AN ISOLATED THUNDERSTORM ACROSS
PORTIONS OF NORTHEAST IOWA INTO EXTREME SOUTHWEST WISCONSIN. THE
IMPACT TO THE TAFS WILL BE AN INCREASE IN SCT TO BKN MID TO HIGH
LEVEL CLOUDS. A COLD FRONT THEN PUSHES THROUGH FROM WEST TO EAST
BY MID TO LATE WEDNESDAY MORNING WITH WINDS SWITCHING TO THE
WEST/NORTHWEST AND INCREASING TO 10 TO 14 KTS WITH GUSTS TO 22 KTS
POSSIBLE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...WETENKAMP